Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/06/14


AREA FORECAST DISCUSSION
NWS PHOENIX AZ
315 PM MST FRI JUL 4 2014 .SYNOPSIS... MONSOON MOISTURE WILL REMAIN IN PLACE ACROSS THE REGION FOR THE NEXT SEVERAL DAYS...RESULTING IN SLIGHTLY COOLER TEMPERATURES...HIGHER HUMIDITIES...AND DAILY CHANCES OF SHOWERS AND THUNDERSTORMS. THE THREAT OF SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH NEXT WEEK. && .DISCUSSION... LATEST SATELLITE IMAGERY AND STREAMLINE ANALYSIS SHOW A DEVELOPING AREA OF LOW PRESSURE IN THE LOWER CO RIVER VALLEY. EARLIER CLOUDINESS CONTINUES TO DISSIPATE ACROSS SOUTH-CENTRAL AZ...THOUGH SURFACE DEWPOINTS REMAIN ELEVATED IN THE 50S AND 60S WHILE THE GPS-IPW AT TEMPE MEASURED AROUND 1.7 INCHES. LATEST MDCRS FLIGHTS OUT OF PHOENIX SHOW A 15-20 KT SOUTHEASTERLY FLOW IN THE MID-LEVELS BETWEEN THE AFOREMENTIONED LOW AND AN ANTICYCLONE ACROSS NM. THE PREFERENCE AGAIN IS CLEARLY TOWARDS THE HRRR WHICH HAS CAPTURED THE CURRENT CONDITIONS WELL. LATEST MESOANALYSIS INDICATES A CONSIDERABLE AMOUNT OF CIN ACROSS THE LOWER DESERTS DUE TO THE DELAYED INSOLATION. GIVEN THE STEERING FLOW PARALLEL TO THE MOGOLLON RIM...CONVECTION ALONG THE RIM IS SHOWING LITTLE TENDENCY TO PROPAGATE INTO THE LOWER ELEVATIONS. SUBSEQUENT CONVECTIVE INITIATION IS EXPECTED ALONG THE EASTERN AND NORTHERN FLANKS OF THE AFOREMENTIONED LOW...WHICH ESSENTIALLY LEAVES CENTRAL AZ IN A LESS FAVORED AREA. NEVERTHELESS...CONDITIONS REMAIN MOIST ENOUGH FOR ISOLATED AIR MASS THUNDERSTORMS IN THE LOWER DESERTS AS FAR WEST AS SE CA...INCLUDING YUMA. MAIN THREATS REMAIN BRIEF HEAVY RAIN...ISOLATED STRONG WIND GUSTS AND BLOWING DUST. && .PREVIOUS DISCUSSION... ACTIVE PATTERN FORECAST TO CONTINUE INTO SATURDAY AND SUNDAY AS WELL...WITH VIRTUALLY IDENTICAL PWATS EACH AFTERNOON AND MLCAPES AROUND 500-1000 J/KG. MUCH OF THE FORECAST THIS WEEKEND WILL BE DICTATED BY WHERE AND HOW MUCH CONVECTION DEVELOPS TODAY /LINGERING BOUNDARIES...HOW WORKED OVER THE BOUNDARY LAYER IS...ETC.../ SO I WILL KEEP A BROAD-BRUSHED APPROACH TO THE POPS AND KEEP THEM WELL ABOVE CLIMATOLOGICAL NORMALS. MOISTURE AND INSTABILITY WILL REMAIN IN PLACE FOR MUCH OF THE UPCOMING WEEK HOWEVER THE ONLY DAY TO FEATURE ANY SORT OF NOTEWORTHY INVERTED TROUGH/PV ANOMALY IS TUESDAY. WILL BE INTERESTING TO SEE IF THIS ACTUALLY MATERIALIZES OR IF THIS IS JUST CONVECTIVE FEEDBACK BEING ADVECTED WITH THE MEAN FLOW INTO THE FORECAST AREA. WILL MAINTAIN A CLIMO-LIKE APPEARANCE TO THE POPS EACH DAY THROUGH THE END OF THE WEEK...HIGHLIGHTING THE HIGHER TERRAIN NORTH/EAST OF PHOENIX. AS FOR TEMPERATURES...GIVEN THE SUBSTANTIAL INCREASE IN MOISTURE THAT OCCURRED THIS EVENING...I WENT AHEAD AND LOWERED HIGHS A FEW DEGREES FOR TODAY...ONLY TOPPING OUT JUST ABOVE THE 100 DEGREE MARK. AS PWATS CHANGE LITTLE EACH DAY THROUGH THE END OF NEXT WEEK...HIGHS SHOULD GENERALLY RUN A FEW DEGREES BELOW NORMAL. BIAS CORRECTED CONSENSUS GUIDANCE IS ON BOARD WITH THE IDEA OF HIGHS AROUND 102-105 EACH AFTERNOON. ON THE OTHER HAND...EVENING CLOUD COVER AND HIGH HUMIDITIES WILL RESULT IN SOME RATHER UNCOMFORTABLE LOWS IN THE UPPER 80S OR EVEN LOWER 90S. OF COURSE OUTFLOWS FROM THUNDERSTORMS WOULD LOWER TEMPERATURES A BIT BUT WILL STICK WITH THE IDEA OF VERY WARM OVERNIGHT TEMPS THROUGH NEXT WEEK. && .AVIATION... SOUTH-CENTRAL AND SOUTHWEST ARIZONA INCLUDING KPHX...KIWA...KSDL... THE BULK OF THUNDERSTORM ACTIVITY WILL BE FOCUSED WELL NORTH AND EAST OF PHOENIX...MAINLY THE MOUNTAINS ALONG THE MOGOLLON RIM AND WHITE MOUNTAINS. STILL NOT OUT OF THE QUESTION FOR ISOLATED STORMS TO FORM OVER THE SOUTH-CENTRAL ARIZONA DESERTS EVEN WITH THE MORE STABLE AIRMASS DUE TO CLOUD COVER AND COOLER SURFACE TEMPERATURES. STRONG OUTFLOWS AND BLOWING DUST FROM DISTANT STORMS ARE STILL POSSIBLE...HOWEVER...WEATHER AND VISIBILITY REDUCTIONS ARE NOT INTRODUCED IN THE TAFS AT THIS TIME DUE TO SPATIAL/TEMPORAL UNCERTAINTY. SOUTHEAST CALIFORNIA INCLUDING KIPL AND KBLH... A WEATHER DISTURBANCE CENTERED OVER THE NORTHERN GULF OF CALIFORNIA WILL WILL KEEP THE POTENTIAL FOR ISOLATED THUNDERSTORM DEVELOPMENT ACROSS THE AREA DURING THE PERIOD. HOWEVER CLOUD COVER WILL CONTINUE TO INHIBIT DAYTIME INSTABILITY AND IN TURN STORM DEVELOPMENT. THUS TAFS DO NOT CURRENTLY DEPICT STORM ACTIVITY...BUT THAT COULD VERY WELL CHANGE LATER THIS AFTERNOON/EVENING. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... MONDAY THROUGH FRIDAY... ELEVATED STORM CHANCES APPEAR LIKELY THROUGH THE END OF NEXT WEEK AS DEEP MONSOON MOISTURE HAS ARRIVED ACROSS THE AREA. THE HIGHEST PRECIP CHANCES WILL BE NORTH/EAST OF PHOENIX BUT EVEN PORTIONS OF THE LOWER DESERTS COULD SEE WETTING RAINS. HUMIDITIES WILL REMAIN QUITE HIGH WITH GOOD OVERNIGHT RECOVERIES DURING THE PERIOD. GIVEN THE INCREASED HUMIDITY LEVELS...TEMPERATURES SHOULD BE AT OR SLIGHTLY BELOW NORMAL. OUTSIDE OF THUNDERSTORM INDUCED OUTFLOWS... WINDS SHOULD BE FAIRLY QUIET AND SHOULD FOLLOW THE USUAL UPSLOPE DRAINAGE PATTERNS. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...HIRSCH PREVIOUS DISCUSSION...LEINS AVIATION...MEYERS FIRE WEATHER...MEYERS/LEINS
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
220 PM MST FRI JUL 4 2014 .SYNOPSIS... MONSOON MOISTURE WILL REMAIN IN PLACE ACROSS THE REGION FOR THE NEXT SEVERAL DAYS...RESULTING IN SLIGHTLY COOLER TEMPERATURES...HIGHER HUMIDITIES...AND DAILY CHANCES OF SHOWERS AND THUNDERSTORMS. THE THREAT OF SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH NEXT WEEK. && .DISCUSSION... LATEST SATELLITE IMAGERY AND STREAMLINE ANALYSIS SHOW A DEVELOPING AREA OF LOW PRESSURE IN THE LOWER CO RIVER VALLEY. EARLIER CLOUDINESS CONTINUES TO DISSIPATE ACROSS SOUTH-CENTRAL AZ...THOUGH SURFACE DEWPOINTS REMAIN ELEVATED IN THE 50S AND 60S WHILE THE GPS-IPW AT TEMPE MEASURED AROUND 1.7 INCHES. LATEST MDCRS FLIGHTS OUT OF PHOENIX SHOW A 15-20 KT SOUTHEASTERLY FLOW IN THE MID-LEVELS BETWEEN THE AFOREMENTIONED LOW AND AN ANTICYCLONE ACROSS NM. THE PREFERENCE AGAIN IS CLEARLY TOWARDS THE HRRR WHICH HAS CAPTURED THE CURRENT CONDITIONS WELL. LATEST MESOANALYSIS INDICATES A CONSIDERABLE AMOUNT OF CIN ACROSS THE LOWER DESERTS DUE TO THE DELAYED INSOLATION. GIVEN THE STEERING FLOW PARALLEL TO THE MOGOLLON RIM...CONVECTION ALONG THE RIM IS SHOWING LITTLE TENDENCY TO PROPAGATE INTO THE LOWER ELEVATIONS. SUBSEQUENT CONVECTIVE INITIATION IS EXPECTED ALONG THE EASTERN AND NORTHERN FLANKS OF THE AFOREMENTIONED LOW...WHICH ESSENTIALLY LEAVES CENTRAL AZ IN A LESS FAVORED AREA. NEVERTHELESS...CONDITIONS REMAIN MOIST ENOUGH FOR ISOLATED AIR MASS THUNDERSTORMS IN THE LOWER DESERTS AS FAR WEST AS SE CA...INCLUDING YUMA. MAIN THREATS REMAIN BRIEF HEAVY RAIN...ISOLATED STRONG WIND GUSTS AND BLOWING DUST. && LATEST SATELLITE IMAGERY AND STREAMLINE ANALYSIS INDICATES THE PRESENCE OF A MID-TROPOSPHERIC VORT MAX AND ASSOCIATED INVERTED TROUGH ACROSS SW AZ. CLOUDINESS AND EVEN SOME ISOLATED SPRINKLES PERSIST THIS MORNING ACROSS MUCH OF AZ. AS MENTIONED IN THE PREVIOUS DISCUSSION...THE MORNING CLOUDS TEND TO COMPLICATE THE DIURNAL HEATING CYCLE AND THE FORECAST FOR CONVECTIVE INITIATION. MODELS IN GENERAL HAVE NOT INITIALIZED WELL THIS MORNING. HOWEVER...CONCEPTUALLY CONVECTION SHOULD BE FAVORED INITIALLY IN THE CLOUD-FREE AREAS OF EASTERN AZ THIS AFTERNOON. THIS MATCHES UP NICELY WITH THE HRRR ENSEMBLE AND THE FORECAST WILL BE WEIGHTED HEAVILY TOWARDS THIS SOLUTION. CONSEQUENTLY...CONVECTION WILL BE INHIBITED ACROSS MUCH OF THE LOWER DESERTS INCLUDING THE PHOENIX AREA UNTIL AT LEAST THIS EVENING. INITIAL TWEAK TO THE FORECAST WILL BE TO NUDGE POPS UPWARD FOR THE HIGHER TERRAIN EAST OF PHOENIX BUT DOWNWARD ACROSS THE LOWER DESERTS. && .PREVIOUS DISCUSSION... ACTIVE PATTERN FORECAST TO CONTINUE INTO SATURDAY AND SUNDAY AS WELL...WITH VIRTUALLY IDENTICAL PWATS EACH AFTERNOON AND MLCAPES AROUND 500-1000 J/KG. MUCH OF THE FORECAST THIS WEEKEND WILL BE DICTATED BY WHERE AND HOW MUCH CONVECTION DEVELOPS TODAY /LINGERING BOUNDARIES...HOW WORKED OVER THE BOUNDARY LAYER IS...ETC.../ SO I WILL KEEP A BROAD-BRUSHED APPROACH TO THE POPS AND KEEP THEM WELL ABOVE CLIMATOLOGICAL NORMALS. MOISTURE AND INSTABILITY WILL REMAIN IN PLACE FOR MUCH OF THE UPCOMING WEEK HOWEVER THE ONLY DAY TO FEATURE ANY SORT OF NOTEWORTHY INVERTED TROUGH/PV ANOMALY IS TUESDAY. WILL BE INTERESTING TO SEE IF THIS ACTUALLY MATERIALIZES OR IF THIS IS JUST CONVECTIVE FEEDBACK BEING ADVECTED WITH THE MEAN FLOW INTO THE FORECAST AREA. WILL MAINTAIN A CLIMO-LIKE APPEARANCE TO THE POPS EACH DAY THROUGH THE END OF THE WEEK...HIGHLIGHTING THE HIGHER TERRAIN NORTH/EAST OF PHOENIX. AS FOR TEMPERATURES...GIVEN THE SUBSTANTIAL INCREASE IN MOISTURE THAT OCCURRED THIS EVENING...I WENT AHEAD AND LOWERED HIGHS A FEW DEGREES FOR TODAY...ONLY TOPPING OUT JUST ABOVE THE 100 DEGREE MARK. AS PWATS CHANGE LITTLE EACH DAY THROUGH THE END OF NEXT WEEK...HIGHS SHOULD GENERALLY RUN A FEW DEGREES BELOW NORMAL. BIAS CORRECTED CONSENSUS GUIDANCE IS ON BOARD WITH THE IDEA OF HIGHS AROUND 102-105 EACH AFTERNOON. ON THE OTHER HAND...EVENING CLOUD COVER AND HIGH HUMIDITIES WILL RESULT IN SOME RATHER UNCOMFORTABLE LOWS IN THE UPPER 80S OR EVEN LOWER 90S. OF COURSE OUTFLOWS FROM THUNDERSTORMS WOULD LOWER TEMPERATURES A BIT BUT WILL STICK WITH THE IDEA OF VERY WARM OVERNIGHT TEMPS THROUGH NEXT WEEK. && .AVIATION... SOUTH-CENTRAL AND SOUTHWEST ARIZONA INCLUDING KPHX...KIWA...KSDL... DEBRIS CLOUDINESS...BASES GENERALLY AOA FL150...FROM LAST NIGHTS STORM ACTIVITY WILL LINGER THROUGH AT LEAST 18Z BEFORE THINNING OUT. ANTICIPATE AFTERNOON DEVELOPMENT OF STORMS OVER THE USUAL HIGHER TERRAIN LOCATIONS OUTSIDE OF THE METRO AREA...MAINLY RIM AND WHITE MOUNTAINS. OUTFLOWS AND DUST FROM DISTANT STORMS WILL BE POSSIBLE ONCE AGAIN. HOWEVER...ANTICIPATE LESS INSTABILITY AVAILABLE LEADING TO WEAKER AND FEWER STORMS ON THE LOW DESERTS OF CENTRAL ARIZONA. A FLY IN THE OINTMENT IS THE PRESENCE OF WEAK CIRCULATION FEATURES IN THE FLOW ALREADY OVER ARIZONA AS WELL AS A LARGER VORT MAX CENTERED OVER THE NORTHERN SEA OF CORTEZ. REMAINS TO BE SEEN HOW THESE FEATURES WILL INFLUENCE THINGS. TAFS REFLECT CONSERVATIVE APPROACH GIVEN THE CONSIDERABLE UNCERTAINTIES. SOUTHEAST CALIFORNIA INCLUDING KIPL AND KBLH... SOME DEBRIS CLOUDINESS WITH BASES ABOVE FL150 WILL LINGER THROUGH AT LEAST 18Z. A WEATHER DISTURBANCE CENTERED OVER THE NORTHERN SEA OF CORTEZ WILL MAY MAINTAIN CLOUDINESS THROUGH THE DAY AND EVEN INCREASE IT. IT COULD ALSO BE A FACTOR IN AIDING STORM DEVELOPMENT. HOWEVER...CLOUD COVER WILL TEND TO INHIBIT INSTABILITY AND IN TURN STORM DEVELOPMENT...AS DOES LACK OF HIGHER TERRAIN. THUS TAFS DO NOT DEPICT STORM ACTIVITY BUT THAT COULD VERY WELL CHANGE LATER THIS MORNING. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... SUNDAY THROUGH THURSDAY... ELEVATED STORM CHANCES APPEAR LIKELY THROUGH THE END OF NEXT WEEK AS DEEP MONSOON MOISTURE HAS ARRIVED ACROSS THE AREA. THE HIGHEST PRECIP CHANCES WILL BE NORTH/EAST OF PHOENIX BUT EVEN PORTIONS OF THE LOWER DESERTS COULD SEE RAINFALL. HUMIDITIES WILL REMAIN QUITE HIGH WITH GOOD OVERNIGHT RECOVERIES EXPECTED. GIVEN THE INCREASED HUMIDITIES...TEMPERATURES SHOULD BE AT OR SLIGHTLY BELOW NORMAL . OUTSIDE OF THUNDERSTORM INDUCED OUTFLOWS...WINDS SHOULD BE FAIRLY QUIET AND SHOULD FOLLOW THE USUAL UPSLOPE/DRAINAGE PATTERNS. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...HIRSCH PREVIOUS DISCUSSION...LEINS AVIATION....AJ FIRE WEATHER...LEINS
AREA FORECAST DISCUSSION...CORRECTED
NWS TUCSON AZ
950 AM MST FRI JUL 4 2014 CORRECTED DISCUSSION TO UPDATE POPS THIS AFTERNOON/EVENING .SYNOPSIS...ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ACROSS SOUTHEAST ARIZONA TODAY. SOME STORMS WILL GENERATE LOCALLY HEAVY RAINFALL AND STRONG GUSTY WINDS. A CHANCE OF THUNDERSTORMS WILL CONTINUE THIS WEEKEND AND INTO NEXT WEEK. && .DISCUSSION...IR/VISIBLE SATELLITE IMAGERY AND SURFACE OBSERVATIONS INDICATE MOSTLY CLOUDY SKIES ACROSS MUCH OF SE AZ AT THIS TIME. THE EXCEPTION WAS ACROSS THE WHITE MOUNTAINS WHERE MOSTLY SUNNY SKIES PREVAILED. DEWPOINTS AT LOWER ELEVATIONS VALID 16Z GENERALLY RANGED FROM THE MID 50S-MID 60S F...AND THESE TEMPS WERE ABOUT 5-10 DEGS F HIGHER VERSUS 24 HOURS AGO. SURFACE TEMPS VALID 16Z WERE NEARLY 5-10 DEGS F COOLER VERSUS THIS TIME THUR. 04/12Z KTWC SOUNDING TOTAL PRECIP WATER VALUE WAS 1.55 INCHES...AN INCREASE OF 0.25 INCH VERSUS 24 HOURS AGO. 24 HOUR TEMP CHANGE PLOT DEPICTED ABOUT 2-4 DEGS C OF COOLING THROUGHOUT MUCH OF THE COLUMN. THE STEERING FLOW FOR STORM MOTION WAS MORE SELY VERSUS THUR MORNING. 04/12Z UPPER AIR PLOTS INDICATED 592 DM HIGH PRESSURE CENTERED OVER NWRN NEW MEXICO WITH RIDGE AXIS EXTENDING SEWD INTO THE LOWER MISSISSIPPI RIVER VALLEY. LIGHT SLY-WLY FLOW PREVAILED ABOVE 500 MB. 04/14Z RUC HRRR AND 04/12Z UNIV OF AZ WRF-NAM WERE SIMILAR WITH THE DEVELOPMENT OF COMPOSITE REFLECTIVE ECHOES BY 19Z MAINLY ACROSS THE MOUNTAINS OF ERN PIMA/SWRN GRAHAM/NRN COCHISE COUNTIES. AN EXPANSIVE AREA OF PRECIP ECHOES WERE THEN PROGGED TO EXIST LATER THIS AFTERNOON MOSTLY FROM NEAR THE TUCSON METRO AREA EWD TO THE NEW MEXICO BORDER. WRN PIMA COUNTY IS PROGGED TO REMAIN ESSENTIALLY PRECIP-FREE THIS AFTERNOON...AT LEAST ACCORDING TO THESE TWO MESOSCALE MODELS. GIVEN THE GRADUAL EROSION OF CLOUDS DURING THE PAST 1-2 HOURS FROM TUCSON SEWD...THE AMPLE MOISTURE AND FAVORED STORM MOTION FLOW AS NOTED IN THE AFOREMENTIONED DIAGNOSTICS...HAVE GIVEN INCREASED CREDENCE TO THESE SOLUTIONS. THUS...SCATTERED TO NUMEROUS SHOWERS/ TSTMS SHOULD OCCUR THIS AFTERNOON. THE MAIN CONCERN ASSOCIATED WITH THIS CONVECTIVE ACTIVITY WILL BE BRIEF STRONG WIND GUSTS APPROACHING OR EXCEEDING SEVERE THRESHOLDS. THE INCREASED MOISTURE MAY LEAD TO LOCALIZED FLOODING. THE RUC HRRR AND U OF AZ WRF-NAM THEN DIFFER ON PRECIP PROSPECTS FOR THIS EVENING. ALTHOUGH THE GENERAL COVERAGE IS SIMILAR...THE RUC HRRR FAVORS CENTRAL/ERN SECTIONS VERSUS MORE ACTIVITY WEST TO NORTH OF TUCSON AS PER THE U OF AZ MODEL. AT THIS TIME...WILL MAINTAIN SCATTERED SHOWERS/TSTMS AREA-WIDE THIS EVENING FOLLOWED BY DECREASING COVERAGE OF SHOWERS/TSTMS LATE TONIGHT. HIGH TEMPS THIS AFTERNOON WILL AVERAGE ABOUT 5-10 DEGS F COOLER VERSUS TEMPS ACHIEVED THUR. PER COORD WITH NEIGHBORING WFO/S AND FAVORING THE RUC HRRR...WILL REDUCE POPS THIS AFTERNOON/EVENING ACROSS WRN SECTIONS...AND ADJUST POPS UPWARD ACROSS ERN SECTIONS THIS AFTERNOON/EVENING. PLEASE REFER TO THE ADDITIONAL SECTIONS FOR FURTHER DETAIL. && .AVIATION...VALID THRU 07/18Z. ISOLATED MAINLY -SHRA THIS MORNING FOLLOWED BY SCT-NUMEROUS TSRA/SHRA THIS AFTERNOON INTO THIS EVENING. MVFR VISIBILITIES TO OCCUR WITH +TSRA...AS WELL AS POTENTIAL BRIEF WIND GUSTS TO NEAR 50 KTS. TSRA/SHRA COVERAGE EXPECTED TO DECREASE LATE TONIGHT WITH ISOLATED MAINLY -SHRA SATURDAY MORNING. OTHERWISE...CLOUD DECKS WILL BE AROUND 80-15K FT AGL. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...LOTS OF DEBRIS CLOUDINESS THIS MORNING WHICH WILL DELAY THE DEVELOPMENT OF THUNDERSTORMS THIS AFTERNOON. HOWEVER STILL LOOKING AT SCATTERED THUNDERSTORMS LATER THIS AFTERNOON INTO THIS EVENING. EXPECT STRONG...GUSTY AND ERRATIC WINDS WITH THE STRONGER THUNDERSTORMS. THEREAFTER...MOISTURE WILL BE SUFFICIENT TO PROVIDE SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS THIS WEEKEND AND INTO NEXT WEEK. && .PREV DISCUSSION...HIGH CONSOLIDATED NORTH OF OUR AREA NOW WITH INVERTED IMPULSE ROTATING AROUND TO ENHANCE OUR CONVECTION INTO EARLY WEEKEND. BY LATE SATURDAY INTO SUNDAY THIS FEATURE PUSHES INTO NORTHERN ARIZONA WITH THE EMPHASIS FOR ORGANIZED CONVECTION SHIFTING WITH IT. WE WILL PROBABLY STILL BE ON THE BUSY SIDE SATURDAY...BUT DOWN A LITTLE SUNDAY WITH A COMBINATION OF WEAK SUBSIDENCE BEHIND THE IMPULSE AND A FAIRLY WORKED-OVER ATMOSPHERE FROM PREVIOUS DAYS. THE HIGH SHIFTS INTO A LITTLE LESS FAVORABLE POSITION DEEPER INTO THE GREAT BASIN NORTHWEST OF US...BUT ECMWF FEATURING ANOTHER IMPULSE TO FOCUS CONVECTION FOR SOUTHEAST ARIZONA BY TUESDAY. WE WILL RAMP THINGS UP ACCORDINGLY AFTER A LITTLE LESS COVERAGE SUNDAY AND MONDAY. DEFAULT IS A BLEND OF NAMDNG5 AND ECMWF...WITH CAREFUL CONSIDERATION FOR HRRR AND VARIOUS WRF ITERATIONS. WELCOME TO THE MONSOON! && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON DISCUSSION/AVIATION...FRANCIS PREVIOUS DISCUSSION...MEYER FIRE WEATHER...GLUECK
AREA FORECAST DISCUSSION
NWS TUCSON AZ
930 AM MST FRI JUL 4 2014 .SYNOPSIS...ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ACROSS SOUTHEAST ARIZONA TODAY. SOME STORMS WILL GENERATE LOCALLY HEAVY RAINFALL AND STRONG GUSTY WINDS. A CHANCE OF THUNDERSTORMS WILL CONTINUE THIS WEEKEND AND INTO NEXT WEEK. && .DISCUSSION...IR/VISIBLE SATELLITE IMAGERY AND SURFACE OBSERVATIONS INDICATE MOSTLY CLOUDY SKIES ACROSS MUCH OF SE AZ AT THIS TIME. THE EXCEPTION WAS ACROSS THE WHITE MOUNTAINS WHERE MOSTLY SUNNY SKIES PREVAILED. DEWPOINTS AT LOWER ELEVATIONS VALID 16Z GENERALLY RANGED FROM THE MID 50S-MID 60S F...AND THESE TEMPS WERE ABOUT 5-10 DEGS F HIGHER VERSUS 24 HOURS AGO. SURFACE TEMPS VALID 16Z WERE NEARLY 5-10 DEGS F COOLER VERSUS THIS TIME THUR. 04/12Z KTWC SOUNDING TOTAL PRECIP WATER VALUE WAS 1.55 INCHES...AN INCREASE OF 0.25 INCH VERSUS 24 HOURS AGO. 24 HOUR TEMP CHANGE PLOT DEPICTED ABOUT 2-4 DEGS C OF COOLING THROUGHOUT MUCH OF THE COLUMN. THE STEERING FLOW FOR STORM MOTION WAS MORE SELY VERSUS THUR MORNING. 04/12Z UPPER AIR PLOTS INDICATED 592 DM HIGH PRESSURE CENTERED OVER NWRN NEW MEXICO WITH RIDGE AXIS EXTENDING SEWD INTO THE LOWER MISSISSIPPI RIVER VALLEY. LIGHT SLY-WLY FLOW PREVAILED ABOVE 500 MB. 04/14Z RUC HRRR AND 04/12Z UNIV OF AZ WRF-NAM WERE SIMILAR WITH THE DEVELOPMENT OF COMPOSITE REFLECTIVE ECHOES BY 19Z MAINLY ACROSS THE MOUNTAINS OF ERN PIMA/SWRN GRAHAM/NRN COCHISE COUNTIES. AN EXPANSIVE AREA OF PRECIP ECHOES WERE THEN PROGGED TO EXIST LATER THIS AFTERNOON MOSTLY FROM NEAR THE TUCSON METRO AREA EWD TO THE NEW MEXICO BORDER. WRN PIMA COUNTY IS PROGGED TO REMAIN ESSENTIALLY PRECIP-FREE THIS AFTERNOON...AT LEAST ACCORDING TO THESE TWO MESOSCALE MODELS. GIVEN THE GRADUAL EROSION OF CLOUDS DURING THE PAST 1-2 HOURS FROM TUCSON SEWD...THE AMPLE MOISTURE AND FAVORED STORM MOTION FLOW AS NOTED IN THE AFOREMENTIONED DIAGNOSTICS...HAVE GIVEN INCREASED CREDENCE TO THESE SOLUTIONS. THUS...SCATTERED TO NUMEROUS SHOWERS/ TSTMS SHOULD OCCUR THIS AFTERNOON. THE MAIN CONCERN ASSOCIATED WITH THIS CONVECTIVE ACTIVITY WILL BE BRIEF STRONG WIND GUSTS APPROACHING OR EXCEEDING SEVERE THRESHOLDS. THE INCREASED MOISTURE MAY LEAD TO LOCALIZED FLOODING. THE RUC HRRR AND U OF AZ WRF-NAM THEN DIFFER ON PRECIP PROSPECTS FOR THIS EVENING. ALTHOUGH THE GENERAL COVERAGE IS SIMILAR...THE RUC HRRR FAVORS CENTRAL/ERN SECTIONS VERSUS MORE ACTIVITY WEST TO NORTH OF TUCSON AS PER THE U OF AZ MODEL. AT THIS TIME...WILL MAINTAIN SCATTERED SHOWERS/TSTMS AREA-WIDE THIS EVENING FOLLOWED BY DECREASING COVERAGE OF SHOWERS/TSTMS LATE TONIGHT. HIGH TEMPS THIS AFTERNOON WILL AVERAGE ABOUT 5-10 DEGS F COOLER VERSUS TEMPS ACHIEVED THUR. THERE ARE NO UPDATES PLANNED AT THIS TIME. PLEASE REFER TO THE ADDITIONAL SECTIONS FOR FURTHER DETAIL. && .AVIATION...VALID THRU 07/18Z. ISOLATED MAINLY -SHRA THIS MORNING FOLLOWED BY SCT-NUMEROUS TSRA/SHRA THIS AFTERNOON INTO THIS EVENING. MVFR VISIBILITIES TO OCCUR WITH +TSRA...AS WELL AS POTENTIAL BRIEF WIND GUSTS TO NEAR 50 KTS. TSRA/SHRA COVERAGE EXPECTED TO DECREASE LATE TONIGHT WITH ISOLATED MAINLY -SHRA SATURDAY MORNING. OTHERWISE...CLOUD DECKS WILL BE AROUND 80-15K FT AGL. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...LOTS OF DEBRIS CLOUDINESS THIS MORNING WHICH WILL DELAY THE DEVELOPMENT OF THUNDERSTORMS THIS AFTERNOON. HOWEVER STILL LOOKING AT SCATTERED THUNDERSTORMS LATER THIS AFTERNOON INTO THIS EVENING. EXPECT STRONG...GUSTY AND ERRATIC WINDS WITH THE STRONGER THUNDERSTORMS. THEREAFTER...MOISTURE WILL BE SUFFICIENT TO PROVIDE SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS THIS WEEKEND AND INTO NEXT WEEK. && .PREV DISCUSSION...HIGH CONSOLIDATED NORTH OF OUR AREA NOW WITH INVERTED IMPULSE ROTATING AROUND TO ENHANCE OUR CONVECTION INTO EARLY WEEKEND. BY LATE SATURDAY INTO SUNDAY THIS FEATURE PUSHES INTO NORTHERN ARIZONA WITH THE EMPHASIS FOR ORGANIZED CONVECTION SHIFTING WITH IT. WE WILL PROBABLY STILL BE ON THE BUSY SIDE SATURDAY...BUT DOWN A LITTLE SUNDAY WITH A COMBINATION OF WEAK SUBSIDENCE BEHIND THE IMPULSE AND A FAIRLY WORKED-OVER ATMOSPHERE FROM PREVIOUS DAYS. THE HIGH SHIFTS INTO A LITTLE LESS FAVORABLE POSITION DEEPER INTO THE GREAT BASIN NORTHWEST OF US...BUT ECMWF FEATURING ANOTHER IMPULSE TO FOCUS CONVECTION FOR SOUTHEAST ARIZONA BY TUESDAY. WE WILL RAMP THINGS UP ACCORDINGLY AFTER A LITTLE LESS COVERAGE SUNDAY AND MONDAY. DEFAULT IS A BLEND OF NAMDNG5 AND ECMWF...WITH CAREFUL CONSIDERATION FOR HRRR AND VARIOUS WRF ITERATIONS. WELCOME TO THE MONSOON! && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON DISCUSSION/AVIATION...FRANCIS PREVIOUS DISCUSSION...MEYER FIRE WEATHER...GLUECK
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
920 AM MST FRI JUL 4 2014 .SYNOPSIS... MONSOON MOISTURE WILL REMAIN IN PLACE ACROSS THE REGION FOR THE NEXT SEVERAL DAYS...RESULTING IN SLIGHTLY COOLER TEMPERATURES...HIGHER HUMIDITIES...AND DAILY CHANCES OF SHOWERS AND THUNDERSTORMS. THE THREAT OF SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH NEXT WEEK. && .DISCUSSION... LATEST SATELLITE IMAGERY AND STREAMLINE ANALYSIS INDICATES THE PRESENCE OF A MID-TROPOSPHERIC VORT MAX AND ASSOCIATED INVERTED TROUGH ACROSS SW AZ. CLOUDINESS AND EVEN SOME ISOLATED SPRINKLES PERSIST THIS MORNING ACROSS MUCH OF AZ. AS MENTIONED IN THE PREVIOUS DISCUSSION...THE MORNING CLOUDS TEND TO COMPLICATE THE DIURNAL HEATING CYCLE AND THE FORECAST FOR CONVECTIVE INITIATION. MODELS IN GENERAL HAVE NOT INITIALIZED WELL THIS MORNING. HOWEVER...CONCEPTUALLY CONVECTION SHOULD BE FAVORED INITIALLY IN THE CLOUD-FREE AREAS OF EASTERN AZ THIS AFTERNOON. THIS MATCHES UP NICELY WITH THE HRRR ENSEMBLE AND THE FORECAST WILL BE WEIGHTED HEAVILY TOWARDS THIS SOLUTION. CONSEQUENTLY...CONVECTION WILL BE INHIBITED ACROSS MUCH OF THE LOWER DESERTS INCLUDING THE PHOENIX AREA UNTIL AT LEAST THIS EVENING. INITIAL TWEAK TO THE FORECAST WILL BE TO NUDGE POPS UPWARD FOR THE HIGHER TERRAIN EAST OF PHOENIX BUT DOWNWARD ACROSS THE LOWER DESERTS. && .PREVIOUS DISCUSSION... QUITE AN ACTIVE EVENING ACROSS THE LOWER DESERTS AS WIDESPREAD BLOWING DUST AFFECTED THE PHOENIX METRO AREA. COLLIDING BOUNDARIES OVER THE METRO AROUND 03Z ALLOWED MID LEVEL INSTABILITY TO BE UTILIZED AND THE WESTERN HALF OF THE PHOENIX AREA SAW MEASURABLE PRECIP /SOME SPOTS SAW NEARLY AN INCH OF RAINFALL/. ELEVATED CONVECTION CONTINUES THIS MORNING OVER WESTERN MARICOPA/YUMA/LA PAZ COUNTIES AS OF 08Z...WITH A SECONDARY CLUSTER OF SHOWERS MOVING THROUGH PIMA COUNTY TOWARD THE FORECAST AREA. RAP ANALYSIS INDICATES THERE ARE STILL A FEW HUNDRED J/KG OF MID LEVEL INSTABILITY TO WORK WITH IN THESE AREAS BUT SURFACE INHIBITION HAS INCREASED SUBSTANTIALLY. GIVEN RECENT TRENDS...I EXPECT THAT WE ARE GOING TO SEE THESE SHOWERS PERCOLATE THROUGH THE REST OF THE PRE-DAWN HOURS BEFORE FIZZLING OUT SHORTLY AFTER SUNRISE. GIVEN THEIR ELEVATED NATURE...BRIEF HEAVY RAIN IS THE PRIMARY THREAT. AS USUAL...THE FORECAST IS QUITE COMPLICATED AS NUMERICAL MODELS ARE STRUGGLING TO GET A HANDLE ON THE CURRENT SITUATION. THE INGREDIENTS WILL BE IN PLACE FOR ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON...EVEN ACROSS THE LOWER DESERTS. GENERAL CONSENSUS AMONG THE MODELS IS THAT THERE WILL BE PLENTY OF MOISTURE TO WORK WITH /PWATS AROUND 1.25 TO 1.5 INCHES/ AND SUFFICIENT MLCAPES AROUND 500-700 J/KG. THE NAM/GFS/EURO/RAP ALL INDICATE A SHORTWAVE TROUGH OVER SONORA WILL MOVE THROUGH ARIZONA LATE THIS AFTERNOON...AND WATER VAPOR IMAGERY REVEALS A SUBTLE DARKENING/DRYING OVER CENTRAL SONORA. HOWEVER THE FLY IN THE OINTMENT IS THE EXTENSIVE CLOUD COVER THAT RESIDES ACROSS ALMOST ALL OF ARIZONA. GOING TO BE HARD TO DESTABILIZE IF THIS THICK CLOUD COVER REMAINS IN PLACE ALL DAY AND IF THINGS DONT CLEAR OUT AT LEAST A LITTLE BY EARLY AFTERNOON...IT MAY END UP MUCH LESS ACTIVE THAN PREVIOUSLY THOUGHT. HOWEVER...STEERING LEVEL WINDS IN THE 700-500MB LAYER ARE CURRENTLY ADVECTING CLEAR SKIES INTO FAR WESTERN NEW MEXICO SO THERE IS SOME DEGREE OF CONFIDENCE THINGS WILL CLEAR OUT LATER THIS AFTERNOON. THE INHERITED FORECAST CONTAINED CHANCE POPS FOR NEARLY THE ENTIRE FORECAST AREA AND I ONLY MADE SLIGHT TEMPORAL CHANGES...FOCUSING MORE ON THE 00Z-06Z TIMEFRAME THAN ANYTHING ELSE. I WILL INTRODUCE A MENTION OF PATCHY BLOWING DUST INTO THE FORECAST AS DUST IS CERTAINLY A THREAT ANYWHERE IN THE OPEN DESERTS. HOWEVER WITH AN INCREASED CHANCE OF MEASURABLE RAIN ACROSS MOST OF THE AREA ALONG WITH MUCH HIGHER DEWPOINTS...THAT MAY HELP KEEP THE DUST SETTLED DOWN A BIT. ACTIVE PATTERN FORECAST TO CONTINUE INTO SATURDAY AND SUNDAY AS WELL...WITH VIRTUALLY IDENTICAL PWATS EACH AFTERNOON AND MLCAPES AROUND 500-1000 J/KG. MUCH OF THE FORECAST THIS WEEKEND WILL BE DICTATED BY WHERE AND HOW MUCH CONVECTION DEVELOPS TODAY /LINGERING BOUNDARIES...HOW WORKED OVER THE BOUNDARY LAYER IS...ETC.../ SO I WILL KEEP A BROAD-BRUSHED APPROACH TO THE POPS AND KEEP THEM WELL ABOVE CLIMATOLOGICAL NORMALS. MOISTURE AND INSTABILITY WILL REMAIN IN PLACE FOR MUCH OF THE UPCOMING WEEK HOWEVER THE ONLY DAY TO FEATURE ANY SORT OF NOTEWORTHY INVERTED TROUGH/PV ANOMALY IS TUESDAY. WILL BE INTERESTING TO SEE IF THIS ACTUALLY MATERIALIZES OR IF THIS IS JUST CONVECTIVE FEEDBACK BEING ADVECTED WITH THE MEAN FLOW INTO THE FORECAST AREA. WILL MAINTAIN A CLIMO-LIKE APPEARANCE TO THE POPS EACH DAY THROUGH THE END OF THE WEEK...HIGHLIGHTING THE HIGHER TERRAIN NORTH/EAST OF PHOENIX. AS FOR TEMPERATURES...GIVEN THE SUBSTANTIAL INCREASE IN MOISTURE THAT OCCURRED THIS EVENING...I WENT AHEAD AND LOWERED HIGHS A FEW DEGREES FOR TODAY...ONLY TOPPING OUT JUST ABOVE THE 100 DEGREE MARK. AS PWATS CHANGE LITTLE EACH DAY THROUGH THE END OF NEXT WEEK...HIGHS SHOULD GENERALLY RUN A FEW DEGREES BELOW NORMAL. BIAS CORRECTED CONSENSUS GUIDANCE IS ON BOARD WITH THE IDEA OF HIGHS AROUND 102-105 EACH AFTERNOON. ON THE OTHER HAND...EVENING CLOUD COVER AND HIGH HUMIDITIES WILL RESULT IN SOME RATHER UNCOMFORTABLE LOWS IN THE UPPER 80S OR EVEN LOWER 90S. OF COURSE OUTFLOWS FROM THUNDERSTORMS WOULD LOWER TEMPERATURES A BIT BUT WILL STICK WITH THE IDEA OF VERY WARM OVERNIGHT TEMPS THROUGH NEXT WEEK. && .AVIATION... SOUTH-CENTRAL AND SOUTHWEST ARIZONA INCLUDING KPHX...KIWA...KSDL... DEBRIS CLOUDINESS...BASES GENERALLY AOA FL150...FROM LAST NIGHTS STORM ACTIVITY WILL LINGER THROUGH AT LEAST 18Z BEFORE THINNING OUT. ANTICIPATE AFTERNOON DEVELOPMENT OF STORMS OVER THE USUAL HIGHER TERRAIN LOCATIONS OUTSIDE OF THE METRO AREA...MAINLY RIM AND WHITE MOUNTAINS. OUTFLOWS AND DUST FROM DISTANT STORMS WILL BE POSSIBLE ONCE AGAIN. HOWEVER...ANTICIPATE LESS INSTABILITY AVAILABLE LEADING TO WEAKER AND FEWER STORMS ON THE LOW DESERTS OF CENTRAL ARIZONA. A FLY IN THE OINTMENT IS THE PRESENCE OF WEAK CIRCULATION FEATURES IN THE FLOW ALREADY OVER ARIZONA AS WELL AS A LARGER VORT MAX CENTERED OVER THE NORTHERN SEA OF CORTEZ. REMAINS TO BE SEEN HOW THESE FEATURES WILL INFLUENCE THINGS. TAFS REFLECT CONSERVATIVE APPROACH GIVEN THE CONSIDERABLE UNCERTAINTIES. SOUTHEAST CALIFORNIA INCLUDING KIPL AND KBLH... SOME DEBRIS CLOUDINESS WITH BASES ABOVE FL150 WILL LINGER THROUGH AT LEAST 18Z. A WEATHER DISTURBANCE CENTERED OVER THE NORTHERN SEA OF CORTEZ WILL MAY MAINTAIN CLOUDINESS THROUGH THE DAY AND EVEN INCREASE IT. IT COULD ALSO BE A FACTOR IN AIDING STORM DEVELOPMENT. HOWEVER...CLOUD COVER WILL TEND TO INHIBIT INSTABILITY AND IN TURN STORM DEVELOPMENT...AS DOES LACK OF HIGHER TERRAIN. THUS TAFS DO NOT DEPICT STORM ACTIVITY BUT THAT COULD VERY WELL CHANGE LATER THIS MORNING. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... SUNDAY THROUGH THURSDAY... ELEVATED STORM CHANCES APPEAR LIKELY THROUGH THE END OF NEXT WEEK AS DEEP MONSOON MOISTURE HAS ARRIVED ACROSS THE AREA. THE HIGHEST PRECIP CHANCES WILL BE NORTH/EAST OF PHOENIX BUT EVEN PORTIONS OF THE LOWER DESERTS COULD SEE RAINFALL. HUMIDITIES WILL REMAIN QUITE HIGH WITH GOOD OVERNIGHT RECOVERIES EXPECTED. GIVEN THE INCREASED HUMIDITIES...TEMPERATURES SHOULD BE AT OR SLIGHTLY BELOW NORMAL . OUTSIDE OF THUNDERSTORM INDUCED OUTFLOWS...WINDS SHOULD BE FAIRLY QUIET AND SHOULD FOLLOW THE USUAL UPSLOPE/DRAINAGE PATTERNS. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...HIRSCH PREVIOUS DISCUSSION...LEINS AVIATION....AJ FIRE WEATHER...LEINS
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
530 AM MST FRI JUL 4 2014 .UPDATE... UPDATED AVIATION SECTION. && .SYNOPSIS... MONSOON MOISTURE WILL REMAIN IN PLACE ACROSS THE REGION FOR THE NEXT SEVERAL DAYS...RESULTING IN SLIGHTLY COOLER TEMPERATURES...HIGHER HUMIDITIES...AND DAILY CHANCES OF SHOWERS AND THUNDERSTORMS. THE THREAT OF SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH NEXT WEEK. && .DISCUSSION... QUITE AN ACTIVE EVENING ACROSS THE LOWER DESERTS AS WIDESPREAD BLOWING DUST AFFECTED THE PHOENIX METRO AREA. COLLIDING BOUNDARIES OVER THE METRO AROUND 03Z ALLOWED MID LEVEL INSTABILITY TO BE UTILIZED AND THE WESTERN HALF OF THE PHOENIX AREA SAW MEASURABLE PRECIP /SOME SPOTS SAW NEARLY AN INCH OF RAINFALL/. ELEVATED CONVECTION CONTINUES THIS MORNING OVER WESTERN MARICOPA/YUMA/LA PAZ COUNTIES AS OF 08Z...WITH A SECONDARY CLUSTER OF SHOWERS MOVING THROUGH PIMA COUNTY TOWARD THE FORECAST AREA. RAP ANALYSIS INDICATES THERE ARE STILL A FEW HUNDRED J/KG OF MID LEVEL INSTABILITY TO WORK WITH IN THESE AREAS BUT SURFACE INHIBITION HAS INCREASED SUBSTANTIALLY. GIVEN RECENT TRENDS...I EXPECT THAT WE ARE GOING TO SEE THESE SHOWERS PERCOLATE THROUGH THE REST OF THE PRE-DAWN HOURS BEFORE FIZZLING OUT SHORTLY AFTER SUNRISE. GIVEN THEIR ELEVATED NATURE...BRIEF HEAVY RAIN IS THE PRIMARY THREAT. AS USUAL...THE FORECAST IS QUITE COMPLICATED AS NUMERICAL MODELS ARE STRUGGLING TO GET A HANDLE ON THE CURRENT SITUATION. THE INGREDIENTS WILL BE IN PLACE FOR ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON...EVEN ACROSS THE LOWER DESERTS. GENERAL CONSENSUS AMONG THE MODELS IS THAT THERE WILL BE PLENTY OF MOISTURE TO WORK WITH /PWATS AROUND 1.25 TO 1.5 INCHES/ AND SUFFICIENT MLCAPES AROUND 500-700 J/KG. THE NAM/GFS/EURO/RAP ALL INDICATE A SHORTWAVE TROUGH OVER SONORA WILL MOVE THROUGH ARIZONA LATE THIS AFTERNOON...AND WATER VAPOR IMAGERY REVEALS A SUBTLE DARKENING/DRYING OVER CENTRAL SONORA. HOWEVER THE FLY IN THE OINTMENT IS THE EXTENSIVE CLOUD COVER THAT RESIDES ACROSS ALMOST ALL OF ARIZONA. GOING TO BE HARD TO DESTABILIZE IF THIS THICK CLOUD COVER REMAINS IN PLACE ALL DAY AND IF THINGS DONT CLEAR OUT AT LEAST A LITTLE BY EARLY AFTERNOON...IT MAY END UP MUCH LESS ACTIVE THAN PREVIOUSLY THOUGHT. HOWEVER...STEERING LEVEL WINDS IN THE 700-500MB LAYER ARE CURRENTLY ADVECTING CLEAR SKIES INTO FAR WESTERN NEW MEXICO SO THERE IS SOME DEGREE OF CONFIDENCE THINGS WILL CLEAR OUT LATER THIS AFTERNOON. THE INHERITED FORECAST CONTAINED CHANCE POPS FOR NEARLY THE ENTIRE FORECAST AREA AND I ONLY MADE SLIGHT TEMPORAL CHANGES...FOCUSING MORE ON THE 00Z-06Z TIMEFRAME THAN ANYTHING ELSE. I WILL INTRODUCE A MENTION OF PATCHY BLOWING DUST INTO THE FORECAST AS DUST IS CERTAINLY A THREAT ANYWHERE IN THE OPEN DESERTS. HOWEVER WITH AN INCREASED CHANCE OF MEASURABLE RAIN ACROSS MOST OF THE AREA ALONG WITH MUCH HIGHER DEWPOINTS...THAT MAY HELP KEEP THE DUST SETTLED DOWN A BIT. ACTIVE PATTERN FORECAST TO CONTINUE INTO SATURDAY AND SUNDAY AS WELL...WITH VIRTUALLY IDENTICAL PWATS EACH AFTERNOON AND MLCAPES AROUND 500-1000 J/KG. MUCH OF THE FORECAST THIS WEEKEND WILL BE DICTATED BY WHERE AND HOW MUCH CONVECTION DEVELOPS TODAY /LINGERING BOUNDARIES...HOW WORKED OVER THE BOUNDARY LAYER IS...ETC.../ SO I WILL KEEP A BROAD-BRUSHED APPROACH TO THE POPS AND KEEP THEM WELL ABOVE CLIMATOLOGICAL NORMALS. MOISTURE AND INSTABILITY WILL REMAIN IN PLACE FOR MUCH OF THE UPCOMING WEEK HOWEVER THE ONLY DAY TO FEATURE ANY SORT OF NOTEWORTHY INVERTED TROUGH/PV ANOMALY IS TUESDAY. WILL BE INTERESTING TO SEE IF THIS ACTUALLY MATERIALIZES OR IF THIS IS JUST CONVECTIVE FEEDBACK BEING ADVECTED WITH THE MEAN FLOW INTO THE FORECAST AREA. WILL MAINTAIN A CLIMO-LIKE APPEARANCE TO THE POPS EACH DAY THROUGH THE END OF THE WEEK...HIGHLIGHTING THE HIGHER TERRAIN NORTH/EAST OF PHOENIX. AS FOR TEMPERATURES...GIVEN THE SUBSTANTIAL INCREASE IN MOISTURE THAT OCCURRED THIS EVENING...I WENT AHEAD AND LOWERED HIGHS A FEW DEGREES FOR TODAY...ONLY TOPPING OUT JUST ABOVE THE 100 DEGREE MARK. AS PWATS CHANGE LITTLE EACH DAY THROUGH THE END OF NEXT WEEK...HIGHS SHOULD GENERALLY RUN A FEW DEGREES BELOW NORMAL. BIAS CORRECTED CONSENSUS GUIDANCE IS ON BOARD WITH THE IDEA OF HIGHS AROUND 102-105 EACH AFTERNOON. ON THE OTHER HAND...EVENING CLOUD COVER AND HIGH HUMIDITIES WILL RESULT IN SOME RATHER UNCOMFORTABLE LOWS IN THE UPPER 80S OR EVEN LOWER 90S. OF COURSE OUTFLOWS FROM THUNDERSTORMS WOULD LOWER TEMPERATURES A BIT BUT WILL STICK WITH THE IDEA OF VERY WARM OVERNIGHT TEMPS THROUGH NEXT WEEK. && .AVIATION... SOUTH-CENTRAL AND SOUTHWEST ARIZONA INCLUDING KPHX...KIWA...KSDL... DEBRIS CLOUDINESS...BASES GENERALLY AOA FL150...FROM LAST NIGHTS STORM ACTIVITY WILL LINGER THROUGH AT LEAST 18Z BEFORE THINNING OUT. ANTICIPATE AFTERNOON DEVELOPMENT OF STORMS OVER THE USUAL HIGHER TERRAIN LOCATIONS OUTSIDE OF THE METRO AREA...MAINLY RIM AND WHITE MOUNTAINS. OUTFLOWS AND DUST FROM DISTANT STORMS WILL BE POSSIBLE ONCE AGAIN. HOWEVER...ANTICIPATE LESS INSTABILITY AVAILABLE LEADING TO WEAKER AND FEWER STORMS ON THE LOW DESERTS OF CENTRAL ARIZONA. A FLY IN THE OINTMENT IS THE PRESENCE OF WEAK CIRCULATION FEATURES IN THE FLOW ALREADY OVER ARIZONA AS WELL AS A LARGER VORT MAX CENTERED OVER THE NORTHERN SEA OF CORTEZ. REMAINS TO BE SEEN HOW THESE FEATURES WILL INFLUENCE THINGS. TAFS REFLECT CONSERVATIVE APPROACH GIVEN THE CONSIDERABLE UNCERTAINTIES. SOUTHEAST CALIFORNIA INCLUDING KIPL AND KBLH... SOME DEBRIS CLOUDINESS WITH BASES ABOVE FL150 WILL LINGER THROUGH AT LEAST 18Z. A WEATHER DISTURBANCE CENTERED OVER THE NORTHERN SEA OF CORTEZ WILL MAY MAINTAIN CLOUDINESS THROUGH THE DAY AND EVEN INCREASE IT. IT COULD ALSO BE A FACTOR IN AIDING STORM DEVELOPMENT. HOWEVER...CLOUD COVER WILL TEND TO INHIBIT INSTABILITY AND IN TURN STORM DEVELOPMENT...AS DOES LACK OF HIGHER TERRAIN. THUS TAFS DO NOT DEPICT STORM ACTIVITY BUT THAT COULD VERY WELL CHANGE LATER THIS MORNING. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... SUNDAY THROUGH THURSDAY... ELEVATED STORM CHANCES APPEAR LIKELY THROUGH THE END OF NEXT WEEK AS DEEP MONSOON MOISTURE HAS ARRIVED ACROSS THE AREA. THE HIGHEST PRECIP CHANCES WILL BE NORTH/EAST OF PHOENIX BUT EVEN PORTIONS OF THE LOWER DESERTS COULD SEE RAINFALL. HUMIDITIES WILL REMAIN QUITE HIGH WITH GOOD OVERNIGHT RECOVERIES EXPECTED. GIVEN THE INCREASED HUMIDITIES...TEMPERATURES SHOULD BE AT OR SLIGHTLY BELOW NORMAL . OUTSIDE OF THUNDERSTORM INDUCED OUTFLOWS...WINDS SHOULD BE FAIRLY QUIET AND SHOULD FOLLOW THE USUAL UPSLOPE/DRAINAGE PATTERNS. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...LEINS AVIATION....AJ FIRE WEATHER...LEINS
AREA FORECAST DISCUSSION
NWS TUCSON AZ
235 AM MST FRI JUL 4 2014 .SYNOPSIS...ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ACROSS SOUTHEAST ARIZONA TODAY. SOME STORMS WILL GENERATE LOCALLY HEAVY RAINFALL AND STRONG GUSTY WINDS. A CHANCE OF THUNDERSTORMS WILL CONTINUE OVER THE WEEKEND INTO NEXT WEEK. && .DISCUSSION...BUSY THUNDERSTORM DAY WITH ORGANIZED OUTFLOWS AND DUST ISSUES. ISOLATED TO SCATTERED SHOWERS WITH ISOLATED EMBEDDED THUNDERSTORMS CONTINUE EARLY THIS MORNING WITH LOTS OF DEBRIS LEFT OVER. WE WILL STRUGGLE TO CLEAR OUT AND SOLAR INSOLATION WILL BE INITIALLY LACKING FROM TUCSON WESTWARD TODAY. IN ADDITION...MORNING SHOWERS WILL TEND TO SLOW ANY CONVECTIVE TRENDS FROM TUCSON WESTWARD CONSIDERABLY TODAY. WITH CLEARING IN THE EAST FIRST WE WILL SEE THE BEST HEATING EAST AND SOUTH FIRST...THEN RELY ON OUTFLOWS TO SPREAD ACTIVITY BACK INTO THE TUCSON AREA LATER IN THE AFTERNOON AND THIS EVENING (AFTER THE INITIAL MORNING SHOWER ACTIVITY). DAYTIME HIGHS KNOCKED BACK AS WELL WITH SIGNIFICANT ADJUSTMENTS THERE. BLENDED TOTAL PRECIPITABLE WATER ESTIMATES SHOWING SOUTHEAST ARIZONA WITH 1.2 TO 1.5 INCHES. WE WILL NEED TO WATCH FOR LOCALIZED FLOODING ISSUES A BIT MORE. HIGH CONSOLIDATED NORTH OF OUR AREA NOW WITH INVERTED IMPULSE ROTATING AROUND TO ENHANCE OUR CONVECTION INTO EARLY WEEKEND. BY LATE SATURDAY INTO SUNDAY THIS FEATURE PUSHES INTO NORTHERN ARIZONA WITH THE EMPHASIS FOR ORGANIZED CONVECTION SHIFTING WITH IT. WE WILL PROBABLY STILL BE ON THE BUSY SIDE SATURDAY...BUT DOWN A LITTLE SUNDAY WITH A COMBINATION OF WEAK SUBSIDENCE BEHIND THE IMPULSE AND A FAIRLY WORKED-OVER ATMOSPHERE FROM PREVIOUS DAYS. THE HIGH SHIFTS INTO A LITTLE LESS FAVORABLE POSITION DEEPER INTO THE GREAT BASIN NORTHWEST OF US...BUT ECMWF FEATURING ANOTHER IMPULSE TO FOCUS CONVECTION FOR SOUTHEAST ARIZONA BY TUESDAY. WE WILL RAMP THINGS UP ACCORDINGLY AFTER A LITTLE LESS COVERAGE SUNDAY AND MONDAY. DEFAULT IS A BLEND OF NAMDNG5 AND ECMWF...WITH CAREFUL CONSIDERATION FOR HRRR AND VARIOUS WRF ITERATIONS. WELCOME TO THE MONSOON! && .AVIATION...CONSIDERABLE DEBRIS CLOUDS...WITH DECKS AROUND 8-14KFT AGL...THIS MORNING WITH ISOLATED LIGHT SHOWERS. CLOUD COVER DIMINISHING SOMEWHAT LATER THIS MORNING INTO THIS AFTERNOON WHICH WILL ALLOW FOR MORE SUN TO WORK ON MOIST ATMOSPHERE. SO STILL LOOKING AT SCATTERED TSRA/SHRA THIS AFTERNOON INTO THIS EVENING WITH MVFR VISIBILITIES AND WIND GUSTS UP TO 45 KTS NEAR +TSRA. OTHERWISE SURFACE WIND GENERALLY LESS THAN 10 KNOTS AND DIURNALLY DRIVEN. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...LOTS OF DEBRIS CLOUDINESS THIS MORNING WHICH WILL DELAY THE DEVELOPMENT OF THUNDERSTORMS THIS AFTERNOON. HOWEVER STILL LOOKING AT SCATTERED THUNDERSTORMS LATER THIS AFTERNOON INTO THIS EVENING. EXPECT STRONG...GUSTY AND ERRATIC WINDS WITH THE STRONGER THUNDERSTORMS. THEREAFTER...MOISTURE WILL BE SUFFICIENT TO PROVIDE SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS THIS WEEKEND AND INTO NEXT WEEK. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON MEYER/GLUECK
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
140 AM MST FRI JUL 4 2014 .SYNOPSIS... MONSOON MOISTURE WILL REMAIN IN PLACE ACROSS THE REGION FOR THE NEXT SEVERAL DAYS...RESULTING IN SLIGHTLY COOLER TEMPERATURES...HIGHER HUMIDITIES...AND DAILY CHANCES OF SHOWERS AND THUNDERSTORMS. THE THREAT OF SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH NEXT WEEK. && .DISCUSSION... QUITE AN ACTIVE EVENING ACROSS THE LOWER DESERTS AS WIDESPREAD BLOWING DUST AFFECTED THE PHOENIX METRO AREA. COLLIDING BOUNDARIES OVER THE METRO AROUND 03Z ALLOWED MID LEVEL INSTABILITY TO BE UTILIZED AND THE WESTERN HALF OF THE PHOENIX AREA SAW MEASURABLE PRECIP /SOME SPOTS SAW NEARLY AN INCH OF RAINFALL/. ELEVATED CONVECTION CONTINUES THIS MORNING OVER WESTERN MARICOPA/YUMA/LA PAZ COUNTIES AS OF 08Z...WITH A SECONDARY CLUSTER OF SHOWERS MOVING THROUGH PIMA COUNTY TOWARD THE FORECAST AREA. RAP ANALYSIS INDICATES THERE ARE STILL A FEW HUNDRED J/KG OF MID LEVEL INSTABILITY TO WORK WITH IN THESE AREAS BUT SURFACE INHIBITION HAS INCREASED SUBSTANTIALLY. GIVEN RECENT TRENDS...I EXPECT THAT WE ARE GOING TO SEE THESE SHOWERS PERCOLATE THROUGH THE REST OF THE PRE-DAWN HOURS BEFORE FIZZLING OUT SHORTLY AFTER SUNRISE. GIVEN THEIR ELEVATED NATURE...BRIEF HEAVY RAIN IS THE PRIMARY THREAT. AS USUAL...THE FORECAST IS QUITE COMPLICATED AS NUMERICAL MODELS ARE STRUGGLING TO GET A HANDLE ON THE CURRENT SITUATION. THE INGREDIENTS WILL BE IN PLACE FOR ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON...EVEN ACROSS THE LOWER DESERTS. GENERAL CONSENSUS AMONG THE MODELS IS THAT THERE WILL BE PLENTY OF MOISTURE TO WORK WITH /PWATS AROUND 1.25 TO 1.5 INCHES/ AND SUFFICIENT MLCAPES AROUND 500-700 J/KG. THE NAM/GFS/EURO/RAP ALL INDICATE A SHORTWAVE TROUGH OVER SONORA WILL MOVE THROUGH ARIZONA LATE THIS AFTERNOON...AND WATER VAPOR IMAGERY REVEALS A SUBTLE DARKENING/DRYING OVER CENTRAL SONORA. HOWEVER THE FLY IN THE OINTMENT IS THE EXTENSIVE CLOUD COVER THAT RESIDES ACROSS ALMOST ALL OF ARIZONA. GOING TO BE HARD TO DESTABILIZE IF THIS THICK CLOUD COVER REMAINS IN PLACE ALL DAY AND IF THINGS DONT CLEAR OUT AT LEAST A LITTLE BY EARLY AFTERNOON...IT MAY END UP MUCH LESS ACTIVE THAN PREVIOUSLY THOUGHT. HOWEVER...STEERING LEVEL WINDS IN THE 700-500MB LAYER ARE CURRENTLY ADVECTING CLEAR SKIES INTO FAR WESTERN NEW MEXICO SO THERE IS SOME DEGREE OF CONFIDENCE THINGS WILL CLEAR OUT LATER THIS AFTERNOON. THE INHERITED FORECAST CONTAINED CHANCE POPS FOR NEARLY THE ENTIRE FORECAST AREA AND I ONLY MADE SLIGHT TEMPORAL CHANGES...FOCUSING MORE ON THE 00Z-06Z TIMEFRAME THAN ANYTHING ELSE. I WILL INTRODUCE A MENTION OF PATCHY BLOWING DUST INTO THE FORECAST AS DUST IS CERTAINLY A THREAT ANYWHERE IN THE OPEN DESERTS. HOWEVER WITH AN INCREASED CHANCE OF MEASURABLE RAIN ACROSS MOST OF THE AREA ALONG WITH MUCH HIGHER DEWPOINTS...THAT MAY HELP KEEP THE DUST SETTLED DOWN A BIT. ACTIVE PATTERN FORECAST TO CONTINUE INTO SATURDAY AND SUNDAY AS WELL...WITH VIRTUALLY IDENTICAL PWATS EACH AFTERNOON AND MLCAPES AROUND 500-1000 J/KG. MUCH OF THE FORECAST THIS WEEKEND WILL BE DICTATED BY WHERE AND HOW MUCH CONVECTION DEVELOPS TODAY /LINGERING BOUNDARIES...HOW WORKED OVER THE BOUNDARY LAYER IS...ETC.../ SO I WILL KEEP A BROAD-BRUSHED APPROACH TO THE POPS AND KEEP THEM WELL ABOVE CLIMATOLOGICAL NORMALS. MOISTURE AND INSTABILITY WILL REMAIN IN PLACE FOR MUCH OF THE UPCOMING WEEK HOWEVER THE ONLY DAY TO FEATURE ANY SORT OF NOTEWORTHY INVERTED TROUGH/PV ANOMALY IS TUESDAY. WILL BE INTERESTING TO SEE IF THIS ACTUALLY MATERIALIZES OR IF THIS IS JUST CONVECTIVE FEEDBACK BEING ADVECTED WITH THE MEAN FLOW INTO THE FORECAST AREA. WILL MAINTAIN A CLIMO-LIKE APPEARANCE TO THE POPS EACH DAY THROUGH THE END OF THE WEEK...HIGHLIGHTING THE HIGHER TERRAIN NORTH/EAST OF PHOENIX. AS FOR TEMPERATURES...GIVEN THE SUBSTANTIAL INCREASE IN MOISTURE THAT OCCURRED THIS EVENING...I WENT AHEAD AND LOWERED HIGHS A FEW DEGREES FOR TODAY...ONLY TOPPING OUT JUST ABOVE THE 100 DEGREE MARK. AS PWATS CHANGE LITTLE EACH DAY THROUGH THE END OF NEXT WEEK...HIGHS SHOULD GENERALLY RUN A FEW DEGREES BELOW NORMAL. BIAS CORRECTED CONSENSUS GUIDANCE IS ON BOARD WITH THE IDEA OF HIGHS AROUND 102-105 EACH AFTERNOON. ON THE OTHER HAND...EVENING CLOUD COVER AND HIGH HUMIDITIES WILL RESULT IN SOME RATHER UNCOMFORTABLE LOWS IN THE UPPER 80S OR EVEN LOWER 90S. OF COURSE OUTFLOWS FROM THUNDERSTORMS WOULD LOWER TEMPERATURES A BIT BUT WILL STICK WITH THE IDEA OF VERY WARM OVERNIGHT TEMPS THROUGH NEXT WEEK. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL... SHOWERS AND A FEW THUNDERSTORMS ACROSS SOUTH-CENTRAL ARIZONA WILL GRADUALLY SHIFT TO THE WEST WHILE DIMINISHING BY AROUND MIDNIGHT. STRONG SOUTHEASTERLY OUTFLOW WINDS WILL GRADUALLY LESSEN BY MIDNIGHT...BUT WINDS GUSTING TO 30 KNOTS WILL LIKELY PERSIST FOR A FEW MORE HOURS. WINDS WILL REMAIN A BIT ON THE HIGHER SIDE OUT OF THE EAST SOUTHEAST FOR THE OVERNIGHT HOURS. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE FRIDAY AFTERNOON AND EVENING...ALONG WITH THE POTENTIAL FOR MORE STRONG STORM OUTFLOWS AND BLOWING DUST. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... CLEAR SKIES SHOULD BE THE RULE THROUGH LATE THIS EVENING...WITH SOME MID/UPPER LEVEL DEBRIS CLOUDS SPREADING IN FROM THE EAST AFTER MIDNIGHT. PERSISTENT BREEZY SOUTH TO SOUTHEAST WINDS ARE EXPECTED ACROSS MUCH OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA THROUGH LATE TONIGHT AND AGAIN FRIDAY AFTERNOON AND EVENING. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... SUNDAY THROUGH THURSDAY... ELEVATED STORM CHANCES APPEAR LIKELY THROUGH THE END OF NEXT WEEK AS DEEP MONSOON MOISTURE HAS ARRIVED ACROSS THE AREA. THE HIGHEST PRECIP CHANCES WILL BE NORTH/EAST OF PHOENIX BUT EVEN PORTIONS OF THE LOWER DESERTS COULD SEE RAINFALL. HUMIDITIES WILL REMAIN QUITE HIGH WITH GOOD OVERNIGHT RECOVERIES EXPECTED. GIVEN THE INCREASED HUMIDITIES...TEMPERATURES SHOULD BE AT OR SLIGHTLY BELOW NORMAL . OUTSIDE OF THUNDERSTORM INDUCED OUTFLOWS...WINDS SHOULD BE FAIRLY QUIET AND SHOULD FOLLOW THE USUAL UPSLOPE/DRAINAGE PATTERNS. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...LEINS AVIATION....KUHLMAN FIRE WEATHER...LEINS
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1100 PM MDT THU JUL 3 2014 .UPDATE... ISSUED AT 1006 PM MDT THU JUL 3 2014 WHILE SOME CONVECTION CONTINUES THIS EVENING...COVERAGE HAS DECREASED CONSIDERABLY. LIGHTNING FREQUENCY HAS ALSO DECREASED SUBSTANTIALLY. WITH THAT IN MIND...THE RED FLAG WARNING HAS BEEN ALLOWED TO EXPIRE. DID BUMP UP POPS A LITTLE AFTER 06Z THOUGH AS SHOWERY TYPE PRECIP LOOKS TO CONTINUE A FEW MORE HOURS. UPDATE ISSUED AT 437 PM MDT THU JUL 3 2014 SOME SHOWERS AND ISOLATED STORMS HAVE POPPED UP OVER OUR NRN ZONES THIS AFTN SO BUMPED UP POPS IN THAT AREA FOR THE NEXT FEW HOURS. LITTLE CHANGE TO FORECAST THINKING AS CONVECTION WILL SLOWLY DIE DOWN AS THE FOCUS OF CONVECTION...A WEAK SHORTWAVE TROUGH...PUSHES OFF TO THE EAST. && .SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT) ISSUED AT 330 PM MDT THU JUL 3 2014 MOISTURE IS BEING WRAPPED UP IN COUNTERCLOCKWISE FLOW UNDERNEATH HIGH PRESSURE ALOFT. THIS INCREASE IN MOISTURE WILL ALLOW SHOWERS AND THUNDERSTORMS TO CONTINUE THIS EVENING...THOUGH DECREASING IN COVERAGE AFTER 8PM DUE TO INCREASING STABILITY WITH SFC COOLING. THE MOST LIKELY AREA FOR SHOWERS AND THUNDERSTORMS TO CONTINUE LATE IS ALONG THE SOUTHERN SAN JUAN MOUNTAINS AND ADJACENT VALLEYS. THE RAP SEEMS TO BE HANDLING THE AREA OF CONVECTION WELL TODAY AND PROJECTS MOISTURE TO WRAP BACK AROUND FROM THE EAST AFTER 6PM IN THE SOUTHERN SAN JUAN REGION BUT DISSIPATED BY MIDNIGHT. SCATTERED CONVECTION IS LIKELY ON FRIDAY AFTERNOON AND EVENING AS WELL WITH 0.75 INCH PWATS REMAINING UNDER THE RIDGE...MEDIOCRE 40KT DIVERGENCE ALOFT...AND INCREASED SUNSHINE DUE TO A LACK OF ORGANIZED DISTURBANCE. HOWEVER...DUE TO A LACK OF DYNAMIC FORCING AND STEERING...STORM CELLS SHOULD REMAIN OVER THE MOUNTAINS AND NOT DRIFT INTO THE VALLEYS. THE SOUTHWESTERN COLORADO MOUNTAINS WILL ONCE AGAIN BE FAVORED AS THE BEST MOISTURE WILL BE AVAILABLE IN THIS REGION. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 330 PM MDT THU JUL 3 2014 BROAD UPPER RIDGE OF HIGH PRESSURE OVER THE INTERIOR WEST AND DESERT SOUTHWEST WILL BE THE DOMINANT WEATHER FEATURE THIS WEEKEND AND NEXT WEEK FOR CONTINUED HOT TEMPS. MODELS SLOWLY SHIFT THE CENTER OF THE HIGH NORTH OVER UT/WRN CO THIS WEEKEND. THIS WILL ALLOW MOISTURE POOLING OVER SRN AZ/SRN NM/NWRN MEXICO TO GRADUALLY EXPAND NORTHWARD...WHILE DRIER WESTERLY FLOW SPREADS ACROSS THE NORTH. DAYTIME HEATING AND ANY SMALL DISTURBANCES WILL RESULT IN SHOWERS AND THUNDERSTORM MOST AFTERNOONS IN TYPICAL SUMMERTIME FASHION. STORM COVERAGE WILL RANGE FROM ISOLATED ACROSS THE NORTH AND CENTRAL...TO SCATTERED OVER THE SAN JUANS. PRECIPITABLE WATER VALUES IN THE NEIGHBORHOOD OF 0.5 TO 0.65 INCH THIS SHOULD RESULT IN A MIX OF WET AND DRY STORMS THIS WEEKEND. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1055 PM MDT THU JUL 3 2014 SHOWERS AND STORMS CONTINUE THIS EVENING WITH A SLIM CHANCE FOR SOME TAF SITES BEING AFFECTED. CONFIDENCE IS LOW THIS WILL OCCUR SO KEPT ANY MENTION OF -SHRA OR -TSRA OUT OF TAF FOR THE OVERNIGHT. EXPECT MORE HIGH CLOUDS TOMORROW WITH MORE SHOWERS AND STORMS AGAIN FAVORING SRN AREAS. DID INCLUDE VCTS FOR KDRO AND KTEX TOMORROW AFTERNOON. COVERAGE SHOULD BE A LITTLE LESS THAN SEEN TODAY. MOISTURE CONTENT REMAINS LOW SO EXPECT GUSTY SFC WINDS FROM ANY STORMS THAT FORM. && .FIRE WEATHER... ISSUED AT 330 PM MDT THU JUL 3 2014 WITH MOISTURE EXPECTED TO SLOWLY INCREASE FROM THE SOUTH THIS WEEKEND...STORMS SHOULD TRANSITION TO A MIX OF WET AND DRY. HOT TEMPERATURES WILL CONTINUE THROUGH NEXT WEEK KEEPING THE DRYING POTENTIAL HIGH. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...NONE. UT...NONE. && $$ UPDATE...TGR SHORT TERM...JAM LONG TERM...JAD AVIATION...TGR
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1022 PM MDT THU JUL 3 2014 .UPDATE... ISSUED AT 1006 PM MDT THU JUL 3 2014 WHILE SOME CONVECTION CONTINUES THIS EVENING...COVERAGE HAS DECREASED CONSIDERABLY. LIGHTNING FREQUENCY HAS ALSO DECREASED SUBSTANTIALLY. WITH THAT IN MIND...THE RED FLAG WARNING HAS BEEN ALLOWED TO EXPIRE. DID BUMP UP POPS A LITTLE AFTER 06Z THOUGH AS SHOWERY TYPE PRECIP LOOKS TO CONTINUE A FEW MORE HOURS. UPDATE ISSUED AT 437 PM MDT THU JUL 3 2014 SOME SHOWERS AND ISOLATED STORMS HAVE POPPED UP OVER OUR NRN ZONES THIS AFTN SO BUMPED UP POPS IN THAT AREA FOR THE NEXT FEW HOURS. LITTLE CHANGE TO FORECAST THINKING AS CONVECTION WILL SLOWLY DIE DOWN AS THE FOCUS OF CONVECTION...A WEAK SHORTWAVE TROUGH...PUSHES OFF TO THE EAST. && .SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT) ISSUED AT 330 PM MDT THU JUL 3 2014 MOISTURE IS BEING WRAPPED UP IN COUNTERCLOCKWISE FLOW UNDERNEATH HIGH PRESSURE ALOFT. THIS INCREASE IN MOISTURE WILL ALLOW SHOWERS AND THUNDERSTORMS TO CONTINUE THIS EVENING...THOUGH DECREASING IN COVERAGE AFTER 8PM DUE TO INCREASING STABILITY WITH SFC COOLING. THE MOST LIKELY AREA FOR SHOWERS AND THUNDERSTORMS TO CONTINUE LATE IS ALONG THE SOUTHERN SAN JUAN MOUNTAINS AND ADJACENT VALLEYS. THE RAP SEEMS TO BE HANDLING THE AREA OF CONVECTION WELL TODAY AND PROJECTS MOISTURE TO WRAP BACK AROUND FROM THE EAST AFTER 6PM IN THE SOUTHERN SAN JUAN REGION BUT DISSIPATED BY MIDNIGHT. SCATTERED CONVECTION IS LIKELY ON FRIDAY AFTERNOON AND EVENING AS WELL WITH 0.75 INCH PWATS REMAINING UNDER THE RIDGE...MEDIOCRE 40KT DIVERGENCE ALOFT...AND INCREASED SUNSHINE DUE TO A LACK OF ORGANIZED DISTURBANCE. HOWEVER...DUE TO A LACK OF DYNAMIC FORCING AND STEERING...STORM CELLS SHOULD REMAIN OVER THE MOUNTAINS AND NOT DRIFT INTO THE VALLEYS. THE SOUTHWESTERN COLORADO MOUNTAINS WILL ONCE AGAIN BE FAVORED AS THE BEST MOISTURE WILL BE AVAILABLE IN THIS REGION. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 330 PM MDT THU JUL 3 2014 BROAD UPPER RIDGE OF HIGH PRESSURE OVER THE INTERIOR WEST AND DESERT SOUTHWEST WILL BE THE DOMINANT WEATHER FEATURE THIS WEEKEND AND NEXT WEEK FOR CONTINUED HOT TEMPS. MODELS SLOWLY SHIFT THE CENTER OF THE HIGH NORTH OVER UT/WRN CO THIS WEEKEND. THIS WILL ALLOW MOISTURE POOLING OVER SRN AZ/SRN NM/NWRN MEXICO TO GRADUALLY EXPAND NORTHWARD...WHILE DRIER WESTERLY FLOW SPREADS ACROSS THE NORTH. DAYTIME HEATING AND ANY SMALL DISTURBANCES WILL RESULT IN SHOWERS AND THUNDERSTORM MOST AFTERNOONS IN TYPICAL SUMMERTIME FASHION. STORM COVERAGE WILL RANGE FROM ISOLATED ACROSS THE NORTH AND CENTRAL...TO SCATTERED OVER THE SAN JUANS. PRECIPITABLE WATER VALUES IN THE NEIGHBORHOOD OF 0.5 TO 0.65 INCH THIS SHOULD RESULT IN A MIX OF WET AND DRY STORMS THIS WEEKEND. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 525 PM MDT THU JUL 3 2014 ISOLATED CONVECTION CONTINUES THIS AFTERNOON WITH VCTS NEAR SOME TAFS. HOWEVER...RADAR MOSAIC STARTING SHOW A DOWNTICK IN CONVECTION AND EXPECT THIS TREND TO CONTINUE WITH MOST CONVECTION FINISHED BY 03Z. AFTER THAT TIME...VFR WILL BE PREVALENT THOUGH SOME MID TO HIGH LEVEL CLOUDS WILL STILL BE PRESENT. ANOTHER ROUND OF CONVECTION IS ON TAP FOR TOMORROW WITH MTN TAF SITES POSSIBLY SEEING MORE VCTS OR -TSRA ALONG WITH KDRO AS SRN AREAS DO REMAIN FAVORED. REMAINING TAF SITES WILL SEE SCT SKIES BECOMING BKN AS THE DAY PROGRESSES WITH VFR CONDITIONS BEING THE NORM. && .FIRE WEATHER... ISSUED AT 330 PM MDT THU JUL 3 2014 WITH MOISTURE EXPECTED TO SLOWLY INCREASE FROM THE SOUTH THIS WEEKEND...STORMS SHOULD TRANSITION TO A MIX OF WET AND DRY. HOT TEMPERATURES WILL CONTINUE THROUGH NEXT WEEK KEEPING THE DRYING POTENTIAL HIGH. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...NONE. UT...NONE. && $$ UPDATE...TGR SHORT TERM...JAM LONG TERM...JAD AVIATION...TGR
AREA FORECAST DISCUSSION
NWS TAUNTON MA
231 AM EDT FRI JUL 4 2014 .SYNOPSIS... TROPICAL STORM CONDITIONS LIKELY FRIDAY NIGHT FOR THE COASTAL WATERS SOUTH OF MARTHAS VINEYARD AND NANTUCKET AND EAST OF CAPE COD... WIDESPREAD SHOWERS/THUNDERSTORMS WITH LOCALLY HEAVY RAINFALL ARE EXPECTED FRIDAY INTO FRIDAY NIGHT. ARTHUR WILL PASS SOUTHEAST OF OUR REGION FRIDAY NIGHT SATURDAY HAVING A SIGNIFICANT IMPACT ON THE MARINE COMMUNITY. HIGH PRESSURE THEN BUILDS OVER NEW ENGLAND WITH FAIR AND DRY WEATHER FOR THE WEEKEND. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... WATER VAPOR IMAGERY SHOWING MOIST PLUME FROM HURRICANE ARTHUR GETTING BROUGHT INTO MID LATITUDE TROF AND THIS HELPING SUPPORT LINE OF SHOWERS ON A SW TO NE AXIS ACROSS EASTERN PA...EASTERN NY AND INTO VT AT 06Z. THIS BAND WILL LIKELY GRADUALLY SHIFT EAST OVERNIGHT INTO FAR WESTERN PORTION OF CWA AS SHOWN BY HRRR AND REFLECT THIS IN THE POPS OVERNIGHT. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/... TROPICAL MOISTURE AND REMAINS OF THE COLD FRONT AND APPROACH OF HURRICANE ARTHUR UP THE COAST. HIGH POPS FOR SHOWERS/TSTMS. THETA E RIDGE STARTS THE MORNING OVER EASTERN MASS/RI...EXPECT THIS TO BE THE FAVORED AREA FOR CONVECTION. BUT POPS WILL BE AT LEAST AT LIKELY LEVELS ALL PARTS OF OUR FORECAST AREA. THE PRECIP WILL BE SHOWERY...SO EXPECT RAIN-FREE PERIODS DURING THE DAY. BUT STILL A WARM AND MUGGY DAY. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... HIGHLIGHTS... HIGHLIGHTS... * TROPICAL STORM ARTHUR EXPECTED TO PASS SOUTHEAST OF US FRI NIGHT * HIGH PRESSURE RETURNS FOR THE WEEKEND * INCREASING HEAT AND HUMIDITY EARLY NEXT WEEK DURING FRIDAY NIGHT ARTHUR MAKES ITS CLOSEST APPROACH TO SOUTHERN NEW ENGLAND. THE ECMWF AND NAM TAKE THE CENTER OF ARTHUR JUST S/E OF THE 40N 70W BENCHMARK...WHILE THE GFS CONTINUES TO BE CLOSER TO NANTUCKET. THE NHC TRACK CONTINUES TO HAVE ARTHUR MOST LIKELY PASSING NEAR OR JUST S/E OF THE BENCHMARK. ARTHUR WILL LIKELY BE CLOSE ENOUGH TO BRING THE THREAT OF HEAVY RAINS. THE MAIN HEAVY RAIN THREAT INTO FRIDAY NIGHT LOOKS TO BE ACROSS EASTERN MA AND RI. RAINS FROM ARTHUR LATE FRI/FRI NIGHT COULD TOTAL 2 TO 4 INCHES IN THAT AREA...WITH LOCALIZED HIGHER AMOUNTS POSSIBLE. IN ADDITION...TROPICAL STORM FORCE WINDS ARE EXPECTED ON THE COASTAL WATERS SOUTH AND EAST OF NANTUCKET. THE CAPE AND ISLANDS WILL LIKELY SEE SOME TROPICAL STORM FORCE WIND GUSTS /34 KTS OR GREATER/ DURING THE OVERNIGHT HOURS. IN ADDITION... A TROPICAL STORM WARNING IS NOW IN EFFECT FOR THE FAR SOUTHEASTERNMOST OF OUR COASTAL WATERS...WHERE GUSTS TO 45 KT ARE EXPECTED. THE HIGHEST WINDS FROM HURRICANE ARTHUR ARE EXPECTED TO REMAIN WELL OFFSHORE. SATURDAY...ARTHUR CONTINUES TO MOVE TO THE NORTHEAST...EVENTUALLY BECOMING ABSORBED IN THE MID LEVEL TROUGH OVER NOVA SCOTIA. HEAVY RAINS EXPECTED TO COME TO AN END ALONG EASTERN MA SATURDAY MORNING...POSSIBLY BEFORE THEN. SKIES WILL CLEAR AS HIGH PRESSURE BUILDS IN BEHIND THE COLD FRONT. TEMPERATURES ARE EXPECTED TO REACH INTO THE UPPER 70S TO LOW 80S...BUT THE AIRMASS WILL BECOME NOTICEABLY LESS HUMID AND MORE COMFORTABLE WITH A NORTHWEST WIND. SATURDAY NIGHT AND SUNDAY...HIGH PRESSURE CROSSES THE AREA DURING THE WEEKEND. QUIET AND DRY WEATHER IS EXPECTED. MONDAY THROUGH TUESDAY...EXPECT INCREASING HEAT AND HUMIDITY MONDAY AND TUESDAY AS SOUTHWESTERLY SURFACE WINDS RETURN. A COLD FRONT MAY CROSS THE AREA DURING THE MONDAY NIGHT TO TUESDAY TIMEFRAME...BRINGING THE RENEWED CHANCE FOR SHOWERS AND THUNDERSTORMS. WEDNESDAY AND THURSDAY...IT IS POSSIBLE THAT A WEAK HIGH PRESSURE WILL MOVE OVER OUR AREA...BUT WITH AXIS OF UPPER TROUGH MOVING IN THERE MAY STILL BE A CHANCE FOR SHOWERS. GOING WITH SLIGHT CHANCE POP. && .AVIATION /06Z FRIDAY THROUGH TUESDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. OVERNIGHT...MODERATE CONFIDENCE. AREAS OF IFR CIGS AND VSBYS IN LOW CLOUDS AND FOG ESPECIALLY IN RI AND SE MA. FRIDAY... MODERATE CONFIDENCE. IFR CIGS/VSBYS IN MORNING FOG...THEN GENERALLY MVFR DURING THE DAY WITH PERIODIC IFR CIGS/VSBYS IN HEAVIER RAIN BANDS. SHOWERS IN THE MORNING BUT THEN MORE OF A STEADY MODERATE TO HEAVY RAIN OVER MOST OF THE AREA DURING THE AFTERNOON. KBOS TAF...MODERATE CONFIDENCE. VFR BUT LOW PROBABILITY OF IFR CIGS FOR A TIME BETWEEN 08Z AND 11Z. KBDL TAF...MODERATE CONFIDENCE. VFR BUT PERIODS OF IFR CIGS POSSIBLE 08Z TO 12Z. OUTLOOK...FRIDAY NIGHT THROUGH TUESDAY... FRIDAY NIGHT...MODERATE CONFIDENCE. MVFR CONDITIONS IN LINGERING SHOWERS BECOMING VFR LATE BDL/BAF/ORH AND VICINITY. MHT/BOS/PVD AND EAST...MVFR/IFR CONDITIONS LIKELY IN LOW CLOUDS...FOG...AND HEAVY RAIN. NW WIND GUSTS TO 30 KT POSSIBLE AT CAPE AND ISLAND TERMINALS. SATURDAY...MODERATE CONFIDENCE. VFR BDL/BAF/ORH AND VICNINITY. TO THE EAST...POTENTIAL MVFR/IFR CONDITIONS TO START THE DAY IN LOW CLOUDS...FOG...AND HEAVY RAIN EARLY SATURDAY...WITH GUSTS AROUND 25KTS POSSIBLE TO START. CONDITIONS IMPROVING TO VFR FOR MIDDAY/AFTERNOON. SATURDAY NIGHT THROUGH MONDAY...HIGH CONFIDENCE. MAINLY VFR. TUESDAY...HIGH CONFIDENE. MAINLY VFR WITH SCATTERED MVFR CIGS/VSBYS IN SHOWERS AND THUNDERSTORMS. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. TONIGHT AND FRIDAY... WINDS WILL BE GENERALLY BELOW 25 KNOTS TONIGHT AND FRIDAY. SEAS AROUND 5 FEET ON THE SOUTHERN OUTER WATERS AND LESS THAN 5 FEET FARTHER NORTH. SHOWERS AND TSTMS THIS EVENING AROUND/NORTH OF CAPE ANN...AND THESE COULD PRODUCE WIND GUSTS OVER 35 KNOTS. ADDITIONAL SHOWERS/TSTMS ALL AREAS ON FRIDAY. SHOWER COVERAGE INCREASES FRIDAY AFTERNOON ALONG THE SOUTHERN WATERS AS HURRICANE ARTHUR APPROACHES. OUTLOOK...FRIDAY NIGHT THROUGH TUESDAY... TROPICAL STORM CONDITIONS ARE LIKELY FRIDAY NIGHT FOR THE COASTAL WATERS SOUTH OF MARTHAS VINEYARD AND NANTUCKET AND EAST OF CAPE COD... FRIDAY NIGHT...MODERATE CONFIDENCE. TROPICAL STORM ARTHUR IS FORECAST TO PASS NEAR THE BENCHMARK FRIDAY NIGHT. THIS WILL BRING A PERIOD OF HIGH SEAS AND STRONG WINDS TO THE SOUTHEAST WATERS FRI NIGHT INTO SATURDAY. TROPICAL STORM CONDITIONS ARE LIKELY FRIDAY NIGHT FOR THE COASTAL WATERS SOUTH OF MARTHAS VINEYARD AND NANTUCKET AND EAST OF CAPE COD...IN THIS AREA A TROPICAL STORM WARNING IS IN EFFECT FOR FRIDAY NIGHT. THIS SYSTEM IS LIKELY TO HAVE A SIGNIFICANT IMPACT ON THE MARINE COMMUNITY. SATURDAY...MODERATE CONFIDENCE. WINDS AND SEAS DIMINISH SLOWLY SATURDAY AS ARTHUR MOVES AWAY FROM THE REGION. SATURDAY NIGHT THROUGH SUNDAY...MODERATE CONFIDENCE. QUIET BOATING WEATHER. SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE. EXPECT INCREASING SW WINDS SEAS ON COASTAL WATERS AHEAD OF AN APPROACHING COLD FRONT...WITH SMALL CRAFT CONDITIONS POSSIBLE. && .HYDROLOGY... THE ATMOSPHERE IS JUICY WITH PRECIP WATER VALUES 1.7 TO 2.0 INCHES. WITH NO SIGNIFICANT CHANGE EXPECTED THROUGH FRIDAY NIGHT...THERE IS THE POTENTIAL FOR SHOWERS AND THUNDERSTORMS PRODUCING HEAVY RAINFALL THROUGH THIS TIME. THIS WILL MEAN A CHANCE FOR URBAN AND SMALL STREAM FLASH FLOODING. RIVERS AND STREAMS ARE GENERALLY AT NORMAL LEVELS FOR THIS TIME OF YEAR...EXCEPT BELOW NORMAL ACROSS EASTERN MA AND NORTHERN RI. BECAUSE OF THIS...LARGER TRIBUTARY AND MAINSTEM RIVERS WOULD BE MORE DIFFICULT TO FLOOD. A FLASH FLOOD WATCH CONTINUES ACROSS PORTIONS OF WESTERN MASSACHUSETTS AND SOUTHWESTERN NEW HAMPSHIRE. ANTICIPATE ISSUING A FLASH FLOOD WATCH FOR EASTERN AREAS FOR THE FRI AFTERNOON THROUGH FRI EVENING TIME FRAME. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...FLASH FLOOD WATCH UNTIL 8 AM EDT THIS MORNING FOR CTZ002>004. MA...FLASH FLOOD WATCH UNTIL 8 AM EDT THIS MORNING FOR MAZ002>004- 008>012-026. TROPICAL STORM WARNING FOR MAZ022-024. NH...FLASH FLOOD WATCH UNTIL 8 AM EDT THIS MORNING FOR NHZ011-012- 015. RI...NONE. MARINE...TROPICAL STORM WARNING FOR ANZ231-232-256. SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO NOON EDT SATURDAY FOR ANZ233>235-237. SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 2 AM EDT SATURDAY FOR ANZ236. SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 6 PM EDT SATURDAY FOR ANZ250. HURRICANE WARNING FOR ANZ254-255. && $$ SYNOPSIS...WTB/NMB NEAR TERM...WTB/RLG/THOMPSON SHORT TERM...WTB LONG TERM...NMB AVIATION...WTB/RLG/NMB/THOMPSON MARINE...WTB/NMB HYDROLOGY...STAFF
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
918 AM EDT FRI JUL 4 2014 .SYNOPSIS... HURRICANE ARTHUR WILL MOVE OFF THE MIDDLE ATLANTIC COAST TODAY AND THEN MOVE UP TOWARDS THE NEW ENGLAND WATERS TONIGHT. HIGH PRESSURE WILL MOVE FROM THE OHIO VALLEY TONIGHT...TO OUR AREA SATURDAY NIGHT. THE HIGH WILL MOVE TO THE EAST SUNDAY AND MONDAY. IT WILL BE FOLLOWED BY A COLD FRONT AND DEVELOPING LOW PRESSURE FOR THE MIDDLE OF NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THE FLASH FLOOD WATCH WILL BE CANCELLED FOR MOST OF THE MARYLAND EASTERN SHORE AND THE REST OF THE I95 CORRIDOR INCLUDING THE PHL METRO AREA WITH THE EXCEPTION OF MIDDLESEX COUNTY. ARTHUR`S EYE IS ABOUT 120 MILES SOUTHEAST OF FENWICK ISLAND DELAWARE. ARTHUR CONTINUES TO MOVE NORTHEAST. WE ARE NOW SEEING THE WESTWARD EXTENSION OF THE PCPN BAND HITTING A WALL EAST OF I95 AND THE NJ TURNPIKE. BASED ON THE LATEST HRRR AND COSPA WE HAVE USED THEM AS A BASIS FOR CANCELLING THE WATCH. FARTHER TO THE NORTHWEST PCPN ALONG THE OLD FRONTAL BOUNDARY WHICH HAS A WINTER DEFORMATION ZONE LOOK TO IT CONTINUES TO MOVE NORTHEAST. IT LOOKS AS THOUGH WHEN THE LIFT EXITS THIS BAND LATER THIS MORNING, IT WILL JUST RAIN ITSELF OUT. SEMI-DOWN DELAWARE BAY FLOW AND POSSIBLE HEAVY PCPN TRANSPORTING STRONGER WINDS DOWNWARD HAVE ENHANCED WINDS ON THE DELAWARE SIDE OF THE BAY, AND WE HAVE INCREASED FORECAST WINDS FOR TODAY AND ARE COVERING IT WITH SMW(S) AND SPS(S). IF IT NO LONGER BECOMES JUST A PCPN ENHANCEMENT WE MAY ISSUE SOME SHORT FUSED WIND RELATED ADVISORIES, GALES. WE SLOWED THE ASCENT OF TEMPS THIS MORNING, NOT CONFIDENT ABOUT MAX TEMPS BEING REACHED. PREVIOUS DISCUSSION... THE FLASH FLOOD WATCH CONTINUES FOR CENTRAL/SRN NJ AND THE SERN DELMARVA. LATEST RADAR TRENDS SHOWS A LINE OF HEAVY RAIN FORMING OVER THE SRN DELMARVA AND OFF THE NJ COAST AS THE OUTER BANDS OF ARTHUR INTERACT WITH THE FRONTAL BOUNDARY. EXPECT THIS BAND TO PROGRESS NWD ACROSS THE DELMARVA AND SRN NJ. RAINFALL RATES OF 1-2 INCHES PER HR WILL BE POSSIBLE UNDER THIS BAND. IT WON`T TAKE MUCH ADDITIONAL RAINFALL TO PRODUCE FLASH FLOODING WITH THE GROUND ALREADY SATURATED ACROSS MANY LOCATIONS (DUAL-POL RADAR ESTIMATES FROM KDOX INDICATED A SWATH OF 3-7 INCHES OF RAIN HAD FALLEN LAST NIGHT IN SRN PORTIONS OF TALBOT AND CAROLINE COUNTIES). HURRICANE ARTHUR`S TRACK IS BECOMING INFLUENCED BY THE UPPER TROUGH OVER GREAT LAKES AND HAS STARTED ITS TURN TO THE NORTHEAST AND HAS ACCELERATED IN SPEED. THE OFFICIAL NHC TRACK TAKES ARTHUR FAR ENOUGH OFF THE DELMARVA AND NJ COAST TO SPARE DIRECT WIND/STORM SURGE IMPACTS FROM THE HURRICANE. THE HURRICANE WILL CONTINUE TO INTERACT WITH THE MID-LATITUDE TROUGH AS WELL AS THE SFC FRONTAL BOUNDARY THAT IS STALLED OVER EASTERN PA...RESULTING IN A CONTINUATION OF SHOWERS THIS MRNG. CYCLONIC FLOW ON NWRN PERIPHERY OF THE SYSTEM WILL ENHANCE CONVERGENCE WITHIN THE BAROCLINIC ZONE AS IT MOVES NEWD THIS MRNG. AS A RESULT...EXPECT AN INCREASE IN SHOWERS ACROSS THE DELMARVA AND NEAR THE NJ COAST THIS MRNG. THE HRRR AND SPC WRF IS PICKING UP ON THIS FAIRLY WELL. ACCORDINGLY, THERE IS STILL A HEIGHTENED CONCERN FOR ANOTHER ROUND OF HEAVY RAINFALL IN THESE AREAS. WHILE THE FLASH FLOOD WATCH IS STILL IN EFFECT FOR MOST OF THE CWA THIS MRNG (AND FOR THE DELMARVA/SRN NJ THRU THE AFTN), THE THREAT OF FLASH FLOODING IS DIMINISHING ACROSS THE NORTHWESTERN PART OF THE CWA AS THE INSTABILITY REQUIRED FOR HEAVIER RAINFALL RATES WANES. WILL LIKELY BE ABLE TO TRIM BACK THESE N/W PORTIONS OF THE WATCH LATER THIS MRNG. NW FLOW AROUND THE HURRICANE WILL ALLOW THE COLD FRONT TO FINALLY MOVE THRU THE AREA LATE THIS MRNG AND AFTN. DRIER AIR ADVECTING INTO THE AREA BEHIND THE FRONT WILL BE ACCOMPANIED BY CLEARING FROM WEST TO EAST THIS AFTN. MAX TEMPS GENERALLY IN THE 70S ACROSS THE CWA BUT DID FCST LOW 80S FOR THE DELMARVA AND PHILLY METRO WHERE CLEARING SKIES WILL ALLOW FOR TEMPS TO REBOUND LATER IN THE AFTN. NW WINDS WILL BE GUSTY DURING THE AFTN AS THE HURRICANE MOVES TOWARD NEW ENGLAND. EXPECT WIND GUSTS AROUND 30 MPH BY LATE THIS AFTN. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/... WITH PLENTY OF FIREWORKS SCHEDULED FOR SHORTLY AFTER SUNSET (WHICH IS AROUND 830 PM), SKIES WILL BE CLEAR FOR MUCH OF THE AREA IN TIME ALTHOUGH SOME CLOUDS MAY LINGER OVER COASTAL AREAS. THE MAIN WX-RELATED IMPACT FOR FIREWORKS WILL BE THE GUSTY WINDS. A TIGHT PRESSURE GRADIENT (FOR JULY STANDARDS) WILL PERSIST ACROSS THE AREA AS HIPRES BUILDS IN FROM THE MIDWEST AND HURRICANE ARTHUR PULLS AWAY FROM THE AREA TOWARD THE CANADIAN MARITIME. NW WINDS MAY GUST 25-35 MPH DURING THE EARLY EVENING BUT WILL START TO DIMINISH AROUND OR SHORTLY AFTER SCHEDULED FIREWORKS TIME. SUSTAINED WINDS AROUND 5-15 MPH WILL CONTINUE OVERNIGHT. MIN TEMP FCST WEIGHTED ON THE WARMER SIDE OF GUIDANCE WITH THE BOUNDARY LAYER REMAINING WELL MIXED. && .LONG TERM /SATURDAY THROUGH THURSDAY/... SAT AND SUN...ARTHUR WILL BE WELL NE OF THE AREA. THE PRESSURE GRADIENT WILL CREATE GUSTY WINDS ACROSS THE REGION SAT AND THE SWELLS MAY CONTINUE TO PRODUCE ROUGH SURF AT THE OCEAN. THE SENSIBLE WEATHER THIS WEEKEND WILL BE DRY WITH SEASONABLE TEMPERATURES AND COMFORTABLE HUMIDITY LEVELS. THIS CONTINUES A DECENT TRACK RECORD OF FAIR WEATHER WEEKEND. HIGHS SAT MOSTLY IN THE LOW 80S AND A FEW DEGREES HIGHER SUN. A FEW UPPER 80S POSSIBLE ACROSS SRN DE ON SUNDAY. MON...A WEAK H5 TROUGH ACROSS THE GREAT LAKES WILL CAUSE LOW PRESSURE TO PASS WELL NORTH OF THE AREA. HIGH PRESSURE OFF THE COAST WILL CREATE A RETURN FLOW WHICH WILL CAUSE HUMIDITY LEVELS TO RISE ONCE AGAIN. THE HEAT AND HUMIDITY WILL BE BACK MON WITH HIGH TEMPERATURES ONCE AGAIN IN THE UPPER 80S AND LOW 90S ACROSS MOST AREAS. THERE IS A SMALL CHC FOR A SHOWER/TSTM ACROSS THE FAR N/W...BUT OTHER THAN THAT DRY ACROSS A VAST MAJORITY OF THE FORECAST AREA. TUE AND WED...THERE IS A BETTER CHC FOR SHOWERS AND TSTMS THIS PERIOD AS A COLD FRONT APPROACHES AND SLOWS ACROSS THE AREA. A WEAK LOW WILL DEVELOP ALONG THE FRONT...FURTHER SLOWING IT WED. THERE IS A CHC OR SLGT CHC FOR SHOWERS AND TSTMS ON BOTH DAYS IN MOST AREAS. THE N/W AREAS ARE MOST FAVORED. TEMPS WILL RUN A BIT ABOVE NORMAL BOTH DAYS WITH MID/UPPER 80S IN MOST AREAS. (COOLER ACROSS THE SRN POCONOS AND A BIT WARMER OVER SRN DELAWARE). THU...WEAK HIGH PRESSURE IS EXPECTED TO MOVE ACROSS THE AREA...SO THE CHCS FOR PCPN WILL BE LESS THAN THE EARLIER FEW DAYS. WE WILL STILL KEEP A SMALL CHC FOR A SHOWER/TSTM AS OFFERED BY WPC. TEMPS WILL CONTINUE TO RUN A FEW DEGREES ABOVE NORMAL. && .AVIATION /13Z FRIDAY THROUGH TUESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. GENERALLY VFR CONDITIONS EARLY THIS MRNG DESPITE AREAS OF SHRA OVER THE AREA. A PERIOD OF MVFR POSSIBLE IN MODERATE SHRA THIS MRNG AND BRIEFLY/LOCALIZED IFR RESTRICTIONS IN HEAVY SHRA. NLY WINDS WILL INCREASE THRUOUT THE DAY AS HURRICANE ARTHUR TRACKS EAST OF THE NRN MID-ATLANTIC REGION. GUST TO 20 KT THIS MRNG AND TO 30 KT BETWEEN ABOUT 18Z-00Z. WINDS WILL DIMINISH TNGT AFTER SUNSET TO 10-15 KT. OUTLOOK... SAT THRU MONDAY...VFR EXPECTED. GUSTY WINDS SAT. TUE...VFR WITH SCT AFTERNOON TSTMS ACROSS THE NORTH/WESTERN TERMINALS. && .MARINE... SEMI-DOWN DELAWARE BAY FLOW AND POSSIBLE HEAVY PCPN TRANSPORTING STRONGER WINDS DOWNWARD HAVE ENHANCED WINDS ON THE DELAWARE SIDE OF THE BAY, AND WE HAVE INCREASED FORECAST WINDS FOR TODAY AND ARE COVERING IT WITH SMW(S) AND SPS(S). IF IT NO LONGER BECOMES JUST A PCPN ENHANCEMENT WE MAY ISSUE SOME SHORT FUSED WIND RELATED ADVISORIES, GALES. LIGHT WINDS THIS MORNING WILL INCREASE RAPIDLY FROM SOUTH TO NORTH LATER THIS MRNG AS HURRICANE ARTHUR MOVES OFF THE MID- ATLANTIC COAST. WIND/WAVE HAZARDS COVERED BY SCA BUT PLEASE NOTE WINDS THAT WIND GUSTS WILL APPROACH CLOSE TO TROPICAL STORM FORCE JUST OFF THE DELMARVA AND SRN NJ COAST THIS AFTN. THE 00Z GFS INDICATES TROPICAL STORM CONDITIONS FOR THESE ZONES WHILE MAJORITY OF OTHER GUIDANCE, INCLUDING FROM NHC, KEEP THE TROPICAL STORM FORCE WINDS ABOUT 25-50 MILES EAST OF THE COASTAL MARINE ZONES. HIGH SURF CAN ALSO BE EXPECTED WITH WAVES OF 6 TO 8 FEET THIS AFTN AND TNGT WHEN ARTHUR IS CLOSEST TO THE AREA. OUTLOOK... SAT...SCA CONDITIONS EARLY WILL DIMINISH LATE. SUN...MOSTLY SUB-SCA CONDITIONS UNTIL EVENING WHEN WINDS AND SEAS WILL APPROACH SCA CONDITIONS. MON...SCA POSSIBLE. && .RIP CURRENTS... BECAUSE OF ARTHUR`S PASS COINCIDING WITH THE START OF THE HOLIDAY WEEKEND, WE HAVE DECIDED TO ISSUE A HIGH SURF ADVISORY FOR TODAY AND TONIGHT, EVEN IF WE WILL FALL A BIT SHORT OF CRITERIA. WE ALSO ARE ANTICIPATING A HIGH RISK FOR RIP CURRENTS. THIS POSES A HUGE CONCERN CONSIDERING THE LARGE NUMBERS OF PEOPLE, INCLUDING THE LESS EXPERIENCED SWIMMERS, WHO WILL VENTURE OUT DURING ONE OF THE BIGGEST BEACH WEEKENDS OF THE YEAR. THE TRANQUIL WEATHER CONDITIONS ON LAND THIS WEEKEND COULD LEAD TO A FALSE SENSE OF SAFETY IN THE WATERS. RIP CURRENTS ARE LIFE-THREATENING IF YOU/RE NOT PREPARED TO HANDLE THEM. FOR THE GREATEST CHANCE OF SAFETY...SWIM ONLY UNDER THE WATCHFUL EYES OF LIFEGUARDS. OTHERWISE ANY OPPORTUNITY FOR RESCUE CAN SUFFER FROM A MUCH GREATER RESPONSE DELAY AND BE FATAL. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...FLASH FLOOD WATCH UNTIL 4 PM EDT THIS AFTERNOON FOR NJZ014- 020>027. HIGH SURF ADVISORY UNTIL 4 PM EDT SATURDAY FOR NJZ014-024>026. FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR NJZ012-013. DE...FLASH FLOOD WATCH UNTIL 4 PM EDT THIS AFTERNOON FOR DEZ002>004. HIGH SURF ADVISORY UNTIL 4 PM EDT SATURDAY FOR DEZ004. MD...FLASH FLOOD WATCH UNTIL 4 PM EDT THIS AFTERNOON FOR MDZ020. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ430-431- 450>455. && $$ SYNOPSIS...O`HARA NEAR TERM...GIGI/KLEIN SHORT TERM...KLEIN LONG TERM...O`HARA AVIATION...KLEIN/O`HARA MARINE...KLEIN/O`HARA RIP CURRENTS...STAFF
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
620 AM EDT FRI JUL 4 2014 .SYNOPSIS... HURRICANE ARTHUR WILL MOVE OFF THE MIDDLE ATLANTIC COAST TODAY AND THEN MOVE UP TOWARDS THE NEW ENGLAND WATERS TONIGHT. HIGH PRESSURE WILL MOVE FROM THE OHIO VALLEY TONIGHT...TO OUR AREA SATURDAY NIGHT. THE HIGH WILL MOVE TO THE EAST SUNDAY AND MONDAY. IT WILL BE FOLLOWED BY A COLD FRONT AND DEVELOPING LOW PRESSURE FOR THE MIDDLE OF NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THE FLASH FLOOD WATCH HAS BEEN CANCELLED FOR ERN PA...NWRN NJ AND CECIL COUNTY IN MD. SHOWERS WILL CONTINUE TO STREAM NORTHWARD INTO THESE AREAS BUT RAINFALL RATES WILL BE GENERALLY LIGHT AND THUS NOT SUPPORTIVE OF FLASH FLOODING. THE FLASH FLOOD WATCH CONTINUES FOR CENTRAL/SRN NJ AND THE DELMARVA. LATEST RADAR TRENDS SHOWS A LINE OF HEAVY RAIN FORMING OVER THE SRN DELMARVA AND OFF THE NJ COAST AS THE OUTER BANDS OF ARTHUR INTERACT WITH THE FRONTAL BOUNDARY. EXPECT THIS BAND TO PROGRESS NWD ACROSS THE DELMARVA AND SRN NJ. RAINFALL RATES OF 1-2 INCHES PER HR WILL BE POSSIBLE UNDER THIS BAND. IT WON`T TAKE MUCH ADDITIONAL RAINFALL TO PRODUCE FLASH FLOODING WITH THE GROUND ALREADY SATURATED ACROSS MANY LOCATIONS (DUAL-POL RADAR ESTIMATES FROM KDOX INDICATED A SWATH OF 3-7 INCHES OF RAIN HAD FALLEN LAST NIGHT IN SRN PORTIONS OF TALBOT AND CAROLINE COUNTIES). PREVIOUS DISCUSSION... HURRICANE ARTHUR IS LOCATED NEAR CAPE HATTERAS AS OF 3 AM WITH A MIN SLP OF 973 MB. THE TRACK OF THIS SYSTEM IS BECOMING INFLUENCED BY THE UPPER TROUGH OVER GREAT LAKES AND HAS STARTED ITS TURN TO THE NORTHEAST AND HAS ACCELERATED IN SPEED. THE OFFICIAL NHC TRACK TAKES ARTHUR FAR ENOUGH OFF THE DELMARVA AND NJ COAST TO SPARE DIRECT WIND/STORM SURGE IMPACTS FROM THE HURRICANE. THE HURRICANE WILL CONTINUE TO INTERACT WITH THE MID-LATITUDE TROUGH AS WELL AS THE SFC FRONTAL BOUNDARY THAT IS STALLED OVER EASTERN PA...RESULTING IN A CONTINUATION OF SHOWERS THIS MRNG. CYCLONIC FLOW ON NWRN PERIPHERY OF THE SYSTEM WILL ENHANCE CONVERGENCE WITHIN THE BAROCLINIC ZONE AS IT MOVES NEWD THIS MRNG. AS A RESULT...EXPECT AN INCREASE IN SHOWERS ACROSS THE DELMARVA AND NEAR THE NJ COAST THIS MRNG. THE HRRR AND SPC WRF IS PICKING UP ON THIS FAIRLY WELL. ACCORDINGLY, THERE IS STILL A HEIGHTENED CONCERN FOR ANOTHER ROUND OF HEAVY RAINFALL IN THESE AREAS. WHILE THE FLASH FLOOD WATCH IS STILL IN EFFECT FOR MOST OF THE CWA THIS MRNG (AND FOR THE DELMARVA/SRN NJ THRU THE AFTN), THE THREAT OF FLASH FLOODING IS DIMINISHING ACROSS THE NORTHWESTERN PART OF THE CWA AS THE INSTABILITY REQUIRED FOR HEAVIER RAINFALL RATES WANES. WILL LIKELY BE ABLE TO TRIM BACK THESE N/W PORTIONS OF THE WATCH LATER THIS MRNG. NW FLOW AROUND THE HURRICANE WILL ALLOW THE COLD FRONT TO FINALLY MOVE THRU THE AREA LATE THIS MRNG AND AFTN. DRIER AIR ADVECTING INTO THE AREA BEHIND THE FRONT WILL BE ACCOMPANIED BY CLEARING FROM WEST TO EAST THIS AFTN. MAX TEMPS GENERALLY IN THE 70S ACROSS THE CWA BUT DID FCST LOW 80S FOR THE DELMARVA AND PHILLY METRO WHERE CLEARING SKIES WILL ALLOW FOR TEMPS TO REBOUND LATER IN THE AFTN. NW WINDS WILL BE GUSTY DURING THE AFTN AS THE HURRICANE MOVES TOWARD NEW ENGLAND. EXPECT WIND GUSTS AROUND 30 MPH BY LATE THIS AFTN. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/... WITH PLENTY OF FIREWORKS SCHEDULED FOR SHORTLY AFTER SUNSET (WHICH IS AROUND 830 PM), SKIES WILL BE CLEAR FOR MUCH OF THE AREA IN TIME ALTHOUGH SOME CLOUDS MAY LINGER OVER COASTAL AREAS. THE MAIN WX-RELATED IMPACT FOR FIREWORKS WILL BE THE GUSTY WINDS. A TIGHT PRESSURE GRADIENT (FOR JULY STANDARDS) WILL PERSIST ACROSS THE AREA AS HIPRES BUILDS IN FROM THE MIDWEST AND HURRICANE ARTHUR PULLS AWAY FROM THE AREA TOWARD THE CANADIAN MARITIME. NW WINDS MAY GUST 25-35 MPH DURING THE EARLY EVENING BUT WILL START TO DIMINISH AROUND OR SHORTLY AFTER SCHEDULED FIREWORKS TIME. SUSTAINED WINDS AROUND 5-15 MPH WILL CONTINUE OVERNIGHT. MIN TEMP FCST WEIGHTED ON THE WARMER SIDE OF GUIDANCE WITH THE BOUNDARY LAYER REMAINING WELL MIXED. && .LONG TERM /SATURDAY THROUGH THURSDAY/... SAT AND SUN...ARTHUR WILL BE WELL NE OF THE AREA. THE PRESSURE GRADIENT WILL CREATE GUSTY WINDS ACROSS THE REGION SAT AND THE SWELLS MAY CONTINUE TO PRODUCE ROUGH SURF AT THE OCEAN. THE SENSIBLE WEATHER THIS WEEKEND WILL BE DRY WITH SEASONABLE TEMPERATURES AND COMFORTABLE HUMIDITY LEVELS. THIS CONTINUES A DECENT TRACK RECORD OF FAIR WEATHER WEEKEND. HIGHS SAT MOSTLY IN THE LOW 80S AND A FEW DEGREES HIGHER SUN. A FEW UPPER 80S POSSIBLE ACROSS SRN DE ON SUNDAY. MON...A WEAK H5 TROUGH ACROSS THE GREAT LAKES WILL CAUSE LOW PRESSURE TO PASS WELL NORTH OF THE AREA. HIGH PRESSURE OFF THE COAST WILL CREATE A RETURN FLOW WHICH WILL CAUSE HUMIDITY LEVELS TO RISE ONCE AGAIN. THE HEAT AND HUMIDITY WILL BE BACK MON WITH HIGH TEMPERATURES ONCE AGAIN IN THE UPPER 80S AND LOW 90S ACROSS MOST AREAS. THERE IS A SMALL CHC FOR A SHOWER/TSTM ACROSS THE FAR N/W...BUT OTHER THAN THAT DRY ACROSS A VAST MAJORITY OF THE FORECAST AREA. TUE AND WED...THERE IS A BETTER CHC FOR SHOWERS AND TSTMS THIS PERIOD AS A COLD FRONT APPROACHES AND SLOWS ACROSS THE AREA. A WEAK LOW WILL DEVELOP ALONG THE FRONT...FURTHER SLOWING IT WED. THERE IS A CHC OR SLGT CHC FOR SHOWERS AND TSTMS ON BOTH DAYS IN MOST AREAS. THE N/W AREAS ARE MOST FAVORED. TEMPS WILL RUN A BIT ABOVE NORMAL BOTH DAYS WITH MID/UPPER 80S IN MOST AREAS. (COOLER ACROSS THE SRN POCONOS AND A BIT WARMER OVER SRN DELAWARE). THU...WEAK HIGH PRESSURE IS EXPECTED TO MOVE ACROSS THE AREA...SO THE CHCS FOR PCPN WILL BE LESS THAN THE EARLIER FEW DAYS. WE WILL STILL KEEP A SMALL CHC FOR A SHOWER/TSTM AS OFFERED BY WPC. TEMPS WILL CONTINUE TO RUN A FEW DEGREES ABOVE NORMAL. && .AVIATION /10Z FRIDAY THROUGH TUESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. GENERALLY VFR CONDITIONS EARLY THIS MRNG DESPITE AREAS OF SHRA OVER THE AREA. A PERIOD OF MVFR POSSIBLE IN MODERATE SHRA THIS MRNG AND BRIEFLY/LOCALIZED IFR RESTRICTIONS IN HEAVY SHRA. NLY WINDS WILL INCREASE THRUOUT THE DAY AS HURRICANE ARTHUR TRACKS EAST OF THE NRN MID-ATLANTIC REGION. GUST TO 20 KT THIS MRNG AND TO 30 KT BETWEEN ABOUT 18Z-00Z. WINDS WILL DIMINISH TNGT AFTER SUNSET TO 10-15 KT. OUTLOOK... SAT THRU MONDAY...VFR EXPECTED. GUSTY WINDS SAT. TUE...VFR WITH SCT AFTERNOON TSTMS ACROSS THE NORTH/WESTERN TERMINALS. && .MARINE... LIGHT WINDS THIS MORNING WILL INCREASE RAPIDLY FROM SOUTH TO NORTH LATER THIS MRNG AS HURRICANE ARTHUR MOVES OFF THE MID- ATLANTIC COAST. WIND/WAVE HAZARDS COVERED BY SCA BUT PLEASE NOTE WINDS THAT WIND GUSTS WILL APPROACH CLOSE TO TROPICAL STORM FORCE JUST OFF THE DELMARVA AND SRN NJ COAST THIS AFTN. THE 00Z GFS INDICATES TROPICAL STORM CONDITIONS FOR THESE ZONES WHILE MAJORITY OF OTHER GUIDANCE, INCLUDING FROM NHC, KEEP THE TROPICAL STORM FORCE WINDS ABOUT 25-50 MILES EAST OF THE COASTAL MARINE ZONES. HIGH SURF CAN ALSO BE EXPECTED WITH WAVES OF 6 TO 8 FEET THIS AFTN AND TNGT WHEN ARTHUR IS CLOSEST TO THE AREA. OUTLOOK... SAT...SCA CONDITIONS EARLY WILL DIMINISH LATE. SUN...MOSTLY SUB-SCA CONDITIONS UNTIL EVENING WHEN WINDS AND SEAS WILL APPROACH SCA CONDITIONS. MON...SCA POSSIBLE. && .RIP CURRENTS... BECAUSE OF ARTHUR`S PASS COINCIDING WITH THE START OF THE HOLIDAY WEEKEND, WE HAVE DECIDED TO ISSUE A HIGH SURF ADVISORY FOR TODAY AND TONIGHT, EVEN IF WE WILL FALL A BIT SHORT OF CRITERIA. WE ALSO ARE ANTICIPATING A HIGH RISK FOR RIP CURRENTS. THIS POSES A HUGE CONCERN CONSIDERING THE LARGE NUMBERS OF PEOPLE, INCLUDING THE LESS EXPERIENCED SWIMMERS, WHO WILL VENTURE OUT DURING ONE OF THE BIGGEST BEACH WEEKENDS OF THE YEAR. THE TRANQUIL WEATHER CONDITIONS ON LAND THIS WEEKEND COULD LEAD TO A FALSE SENSE OF SAFETY IN THE WATERS. RIP CURRENTS ARE LIFE-THREATENING IF YOU/RE NOT PREPARED TO HANDLE THEM. FOR THE GREATEST CHANCE OF SAFETY...SWIM ONLY UNDER THE WATCHFUL EYES OF LIFEGUARDS. OTHERWISE ANY OPPORTUNITY FOR RESCUE CAN SUFFER FROM A MUCH GREATER RESPONSE DELAY AND BE FATAL. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...FLASH FLOOD WATCH UNTIL 4 PM EDT THIS AFTERNOON FOR NJZ014- 020>027. HIGH SURF ADVISORY UNTIL 4 PM EDT SATURDAY FOR NJZ014-024>026. FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR NJZ012-013-015>019. DE...FLASH FLOOD WATCH UNTIL 4 PM EDT THIS AFTERNOON FOR DEZ002>004. HIGH SURF ADVISORY UNTIL 4 PM EDT SATURDAY FOR DEZ004. FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR DEZ001. MD...FLASH FLOOD WATCH UNTIL 4 PM EDT THIS AFTERNOON FOR MDZ012-015- 019-020. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ450>455. SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ430-431. && $$ SYNOPSIS...O`HARA NEAR TERM...KLEIN SHORT TERM...KLEIN LONG TERM...O`HARA AVIATION...KLEIN/O`HARA MARINE...KLEIN/O`HARA RIP CURRENTS...STAFF
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
427 AM EDT FRI JUL 4 2014 .SYNOPSIS... HURRICANE ARTHUR WILL MOVE OFF THE MIDDLE ATLANTIC COAST TODAY AND THEN MOVE UP TOWARDS THE NEW ENGLAND WATERS TONIGHT. HIGH PRESSURE WILL MOVE FROM THE OHIO VALLEY TONIGHT...TO OUR AREA SATURDAY NIGHT. THE HIGH WILL MOVE TO THE EAST SUNDAY AND MONDAY. IT WILL BE FOLLOWED BY A COLD FRONT AND DEVELOPING LOW PRESSURE FOR THE MIDDLE OF NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... HURRICANE ARTHUR IS LOCATED NEAR CAPE HATTERAS AS OF 3 AM WITH A MIN SLP OF 973 MB. THE TRACK OF THIS SYSTEM IS BECOMING INFLUENCED BY THE UPPER TROUGH OVER GREAT LAKES AND HAS STARTED ITS TURN TO THE NORTHEAST AND HAS ACCELERATED IN SPEED. THE OFFICIAL NHC TRACK TAKES ARTHUR FAR ENOUGH OFF THE DELMARVA AND NJ COAST TO SPARE DIRECT WIND/STORM SURGE IMPACTS FROM THE HURRICANE. THE HURRICANE WILL CONTINUE TO INTERACT WITH THE MID-LATITUDE TROUGH AS WELL AS THE SFC FRONTAL BOUNDARY THAT IS STALLED OVER EASTERN PA...RESULTING IN A CONTINUATION OF SHOWERS THIS MRNG. CYCLONIC FLOW ON NWRN PERIPHERY OF THE SYSTEM WILL ENHANCE CONVERGENCE WITHIN THE BAROCLINIC ZONE AS IT MOVES NEWD THIS MRNG. AS A RESULT...EXPECT AN INCREASE IN SHOWERS ACROSS THE DELMARVA AND NEAR THE NJ COAST THIS MRNG. THE HRRR AND SPC WRF IS PICKING UP ON THIS FAIRLY WELL. ACCORDINGLY, THERE IS STILL A HEIGHTENED CONCERN FOR ANOTHER ROUND OF HEAVY RAINFALL IN THESE AREAS. WHILE THE FLASH FLOOD WATCH IS STILL IN EFFECT FOR MOST OF THE CWA THIS MRNG (AND FOR THE DELMARVA/SRN NJ THRU THE AFTN), THE THREAT OF FLASH FLOODING IS DIMINISHING ACROSS THE NORTHWESTERN PART OF THE CWA AS THE INSTABILITY REQUIRED FOR HEAVIER RAINFALL RATES WANES. WILL LIKELY BE ABLE TO TRIM BACK THESE N/W PORTIONS OF THE WATCH LATER THIS MRNG. NW FLOW AROUND THE HURRICANE WILL ALLOW THE COLD FRONT TO FINALLY MOVE THRU THE AREA LATE THIS MRNG AND AFTN. DRIER AIR ADVECTING INTO THE AREA BEHIND THE FRONT WILL BE ACCOMPANIED BY CLEARING FROM WEST TO EAST THIS AFTN. MAX TEMPS GENERALLY IN THE 70S ACROSS THE CWA BUT DID FCST LOW 80S FOR THE DELMARVA AND PHILLY METRO WHERE CLEARING SKIES WILL ALLOW FOR TEMPS TO REBOUND LATER IN THE AFTN. NW WINDS WILL BE GUSTY DURING THE AFTN AS THE HURRICANE MOVES TOWARD NEW ENGLAND. EXPECT WIND GUSTS AROUND 30 MPH BY LATE THIS AFTN. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/... WITH PLENTY OF FIREWORKS SCHEDULED FOR SHORTLY AFTER SUNSET (WHICH IS AROUND 830 PM), SKIES WILL BE CLEAR FOR MUCH OF THE AREA IN TIME ALTHOUGH SOME CLOUDS MAY LINGER OVER COASTAL AREAS. THE MAIN WX-RELATED IMPACT FOR FIREWORKS WILL BE THE GUSTY WINDS. A TIGHT PRESSURE GRADIENT (FOR JULY STANDARDS) WILL PERSIST ACROSS THE AREA AS HIPRES BUILDS IN FROM THE MIDWEST AND HURRICANE ARTHUR PULLS AWAY FROM THE AREA TOWARD THE CANADIAN MARITIME. NW WINDS MAY GUST 25-35 MPH DURING THE EARLY EVENING BUT WILL START TO DIMINISH AROUND OR SHORTLY AFTER SCHEDULED FIREWORKS TIME. SUSTAINED WINDS AROUND 5-15 MPH WILL CONTINUE OVERNIGHT. MIN TEMP FCST WEIGHTED ON THE WARMER SIDE OF GUIDANCE WITH THE BOUNDARY LAYER REMAINING WELL MIXED. && .LONG TERM /SATURDAY THROUGH THURSDAY/... SAT AND SUN...ARTHUR WILL BE WELL NE OF THE AREA. THE PRESSURE GRADIENT WILL CREATE GUSTY WINDS ACROSS THE REGION SAT AND THE SWELLS MAY CONTINUE TO PRODUCE ROUGH SURF AT THE OCEAN. THE SENSIBLE WEATHER THIS WEEKEND WILL BE DRY WITH SEASONABLE TEMPERATURES AND COMFORTABLE HUMIDITY LEVELS. THIS CONTINUES A DECENT TRACK RECORD OF FAIR WEATHER WEEKEND. HIGHS SAT MOSTLY IN THE LOW 80S AND A FEW DEGREES HIGHER SUN. A FEW UPPER 80S POSSIBLE ACROSS SRN DE ON SUNDAY. MON...A WEAK H5 TROUGH ACROSS THE GREAT LAKES WILL CAUSE LOW PRESSURE TO PASS WELL NORTH OF THE AREA. HIGH PRESSURE OFF THE COAST WILL CREATE A RETURN FLOW WHICH WILL CAUSE HUMIDITY LEVELS TO RISE ONCE AGAIN. THE HEAT AND HUMIDITY WILL BE BACK MON WITH HIGH TEMPERATURES ONCE AGAIN IN THE UPPER 80S AND LOW 90S ACROSS MOST AREAS. THERE IS A SMALL CHC FOR A SHOWER/TSTM ACROSS THE FAR N/W...BUT OTHER THAN THAT DRY ACROSS A VAST MAJORITY OF THE FORECAST AREA. TUE AND WED...THERE IS A BETTER CHC FOR SHOWERS AND TSTMS THIS PERIOD AS A COLD FRONT APPROACHES AND SLOWS ACROSS THE AREA. A WEAK LOW WILL DEVELOP ALONG THE FRONT...FURTHER SLOWING IT WED. THERE IS A CHC OR SLGT CHC FOR SHOWERS AND TSTMS ON BOTH DAYS IN MOST AREAS. THE N/W AREAS ARE MOST FAVORED. TEMPS WILL RUN A BIT ABOVE NORMAL BOTH DAYS WITH MID/UPPER 80S IN MOST AREAS. (COOLER ACROSS THE SRN POCONOS AND A BIT WARMER OVER SRN DELAWARE). THU...WEAK HIGH PRESSURE IS EXPECTED TO MOVE ACROSS THE AREA...SO THE CHCS FOR PCPN WILL BE LESS THAN THE EARLIER FEW DAYS. WE WILL STILL KEEP A SMALL CHC FOR A SHOWER/TSTM AS OFFERED BY WPC. TEMPS WILL CONTINUE TO RUN A FEW DEGREES ABOVE NORMAL. && .AVIATION /08Z FRIDAY THROUGH TUESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. GENERALLY VFR CONDITIONS EARLY THIS MRNG DESPITE AREAS OF SHRA OVER THE AREA. A PERIOD OF MVFR POSSIBLE IN MODERATE SHRA THIS MRNG AND BRIEFLY/LOCALIZED IFR RESTRICTIONS IN HEAVY SHRA. NLY WINDS WILL INCREASE THRUOUT THE DAY AS HURRICANE ARTHUR TRACKS EAST OF THE NRN MID-ATLANTIC REGION. GUST TO 20 KT THIS MRNG AND TO 30 KT BETWEEN ABOUT 18Z-00Z. WINDS WILL DIMINISH TNGT AFTER SUNSET TO 10-15 KT. OUTLOOK... SAT THRU MONDAY...VFR EXPECTED. GUSTY WINDS SAT. TUE...VFR WITH SCT AFTERNOON TSTMS ACROSS THE NORTH/WESTERN TERMINALS. && .MARINE... LIGHT WINDS THIS MORNING WILL INCREASE RAPIDLY FROM SOUTH TO NORTH LATER THIS MRNG AS HURRICANE ARTHUR MOVES OFF THE MID- ATLANTIC COAST. WIND/WAVE HAZARDS COVERED BY SCA BUT PLEASE NOTE WINDS THAT WIND GUSTS WILL APPROACH CLOSE TO TROPICAL STORM FORCE JUST OFF THE DELMARVA AND SRN NJ COAST THIS AFTN. THE 00Z GFS INDICATES TROPICAL STORM CONDITIONS FOR THESE ZONES WHILE MAJORITY OF OTHER GUIDANCE, INCLUDING FROM NHC, KEEP THE TROPICAL STORM FORCE WINDS ABOUT 25-50 MILES EAST OF THE COASTAL MARINE ZONES. HIGH SURF CAN ALSO BE EXPECTED WITH WAVES OF 6 TO 8 FEET THIS AFTN AND TNGT WHEN ARTHUR IS CLOSEST TO THE AREA. OUTLOOK... SAT...SCA CONDITIONS EARLY WILL DIMINISH LATE. SUN...MOSTLY SUB-SCA CONDITIONS UNTIL EVENING WHEN WINDS AND SEAS WILL APPROACH SCA CONDITIONS. MON...SCA POSSIBLE. && .RIP CURRENTS... BECAUSE OF ARTHUR`S PASS COINCIDING WITH THE START OF THE HOLIDAY WEEKEND, WE HAVE DECIDED TO ISSUE A HIGH SURF ADVISORY FOR TODAY AND TONIGHT, EVEN IF WE WILL FALL A BIT SHORT OF CRITERIA. WE ALSO ARE ANTICIPATING A HIGH RISK FOR RIP CURRENTS. THIS POSES A HUGE CONCERN CONSIDERING THE LARGE NUMBERS OF PEOPLE, INCLUDING THE LESS EXPERIENCED SWIMMERS, WHO WILL VENTURE OUT DURING ONE OF THE BIGGEST BEACH WEEKENDS OF THE YEAR. THE TRANQUIL WEATHER CONDITIONS ON LAND THIS WEEKEND COULD LEAD TO A FALSE SENSE OF SAFETY IN THE WATERS. RIP CURRENTS ARE LIFE-THREATENING IF YOU/RE NOT PREPARED TO HANDLE THEM. FOR THE GREATEST CHANCE OF SAFETY...SWIM ONLY UNDER THE WATCHFUL EYES OF LIFEGUARDS. OTHERWISE ANY OPPORTUNITY FOR RESCUE CAN SUFFER FROM A MUCH GREATER RESPONSE DELAY AND BE FATAL. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR PAZ060>062-070-071- 101>106. NJ...FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR NJZ001-007>010-012- 013-015>019. FLASH FLOOD WATCH UNTIL 4 PM EDT THIS AFTERNOON FOR NJZ014- 020>027. HIGH SURF ADVISORY FROM 8 AM THIS MORNING TO 6 AM EDT SATURDAY FOR NJZ014-024>026. DE...FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR DEZ001. FLASH FLOOD WATCH UNTIL 4 PM EDT THIS AFTERNOON FOR DEZ002>004. HIGH SURF ADVISORY FROM 8 AM THIS MORNING TO 6 AM EDT SATURDAY FOR DEZ004. MD...FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR MDZ008. FLASH FLOOD WATCH UNTIL 4 PM EDT THIS AFTERNOON FOR MDZ012-015- 019-020. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ450>455. SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 6 AM EDT SATURDAY FOR ANZ430-431. && $$ SYNOPSIS...O`HARA NEAR TERM...KLEIN SHORT TERM...KLEIN LONG TERM...O`HARA AVIATION...KLEIN/O`HARA MARINE...KLEIN/O`HARA RIP CURRENTS...STAFF
AREA FORECAST DISCUSSION
NWS MIAMI FL
252 PM EDT FRI JUL 4 2014 .DISCUSSION... WIDELY DISPERSED SHOWERS/THUNDERSTORMS CONTINUE TO FORM ACROSS THE FLORIDA PENINSULA WITH ISOLATED ACTIVITY ACROSS THE ATLANTIC WATERS. IN GENERAL STORM MOTION IS SLOWLY TO THE NORTHEAST. ADDITIONAL SCATTERED SHOWER/THUNDERSTORM IS EXPECTED THE REMAINDER OF THE AFTERNOON HOURS AND INTO THE EARLY EVENING WITH THE INTERIOR AND EASTERN PORTIONS OF THE PENINSULA EXPECTED TO HAVE THE MOST COVERAGE. THE LATEST HRRR MODEL RUNS SHOW THIS TREND AS WELL. THE GLOBAL MODELS HAVE A GENERAL CONSENSUS INDICATING AN ELONGATED AREA OF DEEP LAYERED MOISTURE AND CLOUDINESS EXTENDING ACROSS THE GULF WATERS THEN EASTWARD ACROSS CENTRAL FLORIDA AND THEN NORTHEASTWARD ACROSS THE ATLANTIC WATERS TOWARD HURRICANE ARTHUR. THE MODELS INDICATE THAT AREA OF MOISTURE CONTINUING TO SINK SOUTHWARD TONIGHT INTO SATURDAY. AT THE SAME TIME A MID TO UPPER LEVEL TROUGH IS FORECAST TO SLOWLY BUILD INTO THE NORTHEASTERN GULF AND EXTEND INTO CENTRAL FLORIDA. THE LATEST GUIDANCE AND CURRENT FORECAST INDICATES AN INCREASE IN SHOWERS/THUNDERSTORMS ACROSS THE REGION FOR SATURDAY AFTERNOON...INCLUDING THE ATLANTIC WATERS. MORE NUMEROUS ACTIVITY IN THE INTERIOR HAS BEEN ADDED TO THE FORECAST FOR SATURDAY AFTERNOON. THE AFOREMENTIONED FEATURES...I.E. THE UPPER LEVEL TROUGH AND MOISTURE...WILL LINGER INTO SUNDAY WITH MAINLY AFTERNOON SCATTERED SHOWERS/THUNDERSTORMS FORECAST. DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS ARE FORECAST TO CONTINUE INTO EARLY NEXT WEEK. && .MARINE... IN GENERAL WINDS ACROSS THE REGIONAL WATERS ARE EXPECTED TO BE 10 KNOTS OR LESS AND SEAS 2 FEET OR LESS THROUGH THE WEEKEND. SOUTHEASTERLY WINDS ARE FORECAST TO CONTINUE BUILDING INTO THE ATLANTIC WATERS AS THE WEEKEND PROGRESSES. WINDS 10 KNOTS OR LESS AND SEAS 2 FEET OR LESS ARE FORECAST TO CONTINUE ACROSS THE REGIONAL WATERS INTO EARLY NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 78 88 77 86 / 30 40 30 40 FORT LAUDERDALE 80 87 79 86 / 30 40 20 40 MIAMI 79 88 78 87 / 30 40 20 40 NAPLES 79 87 78 87 / 20 30 20 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...30/KOB LONG TERM....60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
150 PM EDT FRI JUL 4 2014 .AVIATION... SCATTERED TSRA ALREADY UNDERWAY AND THIS TREND WILL CONTINUE AS THE AFTERNOON PROGRESSES. SEA BREEZE WELL INLAND FROM THE MIAMI- DADE TERMINALS SO DELAYED VCTS FOR KOPF, KMIA AND KTMB UNTIL 20Z WHEN SOME OF CONVECTION COULD MOVE BACK TOWARDS THOSE TERMINALS IN THE NORTHEAST STEERING FLOW. THERE COULD BE SOME BRIEF MVFR/IFR CONDITIONS IF A TSRA MOVES NEAR THE TERMINAL BUT ONLY PLACED THE VCTS FOR NOW WITH SIMILAR CONDITIONS EXPECTED SATURDAY AFT 15Z. KOB && .PREV DISCUSSION... /ISSUED 1024 AM EDT FRI JUL 4 2014/ UPDATE... THERE WERE SOME CHANGES MADE TO THE SHORT TERM FORECAST FOR THIS AFTERNOON AND EARLY EVENING. THE FORECAST FOR THE EAST COAST METRO AREAS WAS UPDATED TO INCLUDE SCATTERED AFTERNOON/EARLY EVENING SHOWERS/THUNDERSTORMS. THE 12Z SOUNDING INDICATED A PWAT OF AROUND 1.9 INCHES. IN ADDITION THERE ARE LOW LEVEL SOUTHWESTERLY WINDS AND MID LEVEL WESTERLY WINDS. WITH THE EAST AND WEST COAST SEA BREEZES EXPECTED TODAY...INITIATION OF CONVECTION IS EXPECTED IN THE INTERIOR PORTIONS OF THE PENINSULA. BUT LATER IN THE AFTERNOON THE AFOREMENTIONED WESTERLY WINDS COULD HELP TO SHIFT SHOWERS/THUNDERSTORMS TOWARDS THE ATLANTIC COASTAL ZONE. THE LATEST GUIDANCE...INCLUDING THE LATEST HRRR MODEL...SUGGESTS THIS TREND AS WELL. SO SCATTERED SHOWERS/THUNDERSTORMS WERE ADDED TO THE ATLANTIC COAST METRO AREAS BUT MAINLY EXPECTED LATE AFTERNOON AND EARLY EVENING. THE 12Z SOUNDING ALSO INDICATED SOME LAYERS OF DRIER AIR IN THE MID LEVELS AND IN THE HAIL GROWTH ZONE SO SMALL HAIL IS POSSIBLE WITH THE STRONGER THUNDERSTORMS. IN ADDITION THERE COULD BE A SLIGHT RISK OF WATERSPOUTS ACROSS THE ATLANTIC WATERS AS THE LOW LEVEL WIND PROFILE IS FAVORABLE. 60 PREV DISCUSSION... /ISSUED 759 AM EDT FRI JUL 4 2014/ AVIATION... MOSTLY VFR IS EXPECTED TODAY WITH SCT TSRA AFT 19-20Z THIS AFTERNOON. LIGHT FLOW WILL GIVE WAY TO SEA BREEZES ALONG BOTH COASTS AROUND 17Z WITH CONVECTION DEVELOPING ALONG THE BOUNDARIES. THE STEERING FLOW IS ERRATIC THIS MORNING AND FORECAST SOUNDINGS SHOW SIMILAR CONDITIONS THROUGHOUT THE DAY. THUS, TSRA MOVEMENT WITH INTERACTIONS BETWEEN BOUNDARIES WILL BE SLOW AND ERRATIC SO ONLY PLACED VCTS IN THE FORECASTS AT THIS TIME BUT THERE COULD BE A BRIEF MVFR/IFR CIG/VSBY FAVORING THE EAST COAST TERMINALS AND WILL AMEND IF NECESSARY. KOB PREV DISCUSSION... /ISSUED 348 AM EDT FRI JUL 4 2014/ DISCUSSION... THE WEATHER PATTERN ACROSS SOUTH FLORIDA WILL BE INFLUENCED BY WEAK LOW PRESSURE TO THE NORTH. THIS WILL KEEP WEAK INSTABILITY OVER THE AREA FOR TODAY. GIVEN THE NOCTURNAL ACTIVITY OF TONIGHT, WILL KEEP SHOWERS AND THUNDERSTORMS IN THE FORECAST THROUGH THE DAY TODAY. LOOKING AT MODEL WINDS, THE STEERING FLOW IS FROM THE SOUTHWEST. IT DOES APPEAR THAT A GULF BREEZE WILL DEVELOP, TURNING THE WINDS SOMEWHAT MORE WESTERLY THIS AFTERNOON, FOR THE WESTERN HALF OF THE CWA. THE ATLANTIC SEA BREEZE SHOWS UP, BUT VERY WEAK AND DOES NOT LOOK AS THOUGH IT WILL BE ABLE TO PENETRATE TOO FAR INLAND, MOST LIKELY DUE TO THE SW FLOW. THIS MAKES THE BETTER CONVERGENCE AREA TO BE IN THE INTERIOR, WITH THE WESTERN INTERIOR AREAS OF BROWARD, PALM BEACH, AND MIAMI DADE COUNTIES, AS WELL AS THE EASTERN AREAS OF COLLIER, GLADES, AND HENDRY COUNTIES. HOWEVER, AS WITH MOST AFTERNOONS IN SOUTH FLORIDA, CAN NOT RULE OUT ANY LOCATION ACROSS THE AREA FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON. AS FOR THEIR INTENSITY, YESTERDAY LOOKED SOMEWHAT BETTER. TODAY, THE 500MB TEMP IS -6.8C. THE 700-500MB LAPSE RATE IS RIGHT AROUND 6 C/KM. THE NCAPE IS AROUND .15 AND CAPE IS LESS THAN 2000 JOULES. SO,. THIS ADDS UP TO MAINLY GARDEN VARIETY THUNDERSTORMS TODAY. THERE IS A DRY LAYER IN THE MID LEVELS THAT COLD HELP BRING A FEW STRONG DOWNBURSTS WITH ANY THUNDERSTORM THAT DEVELOPS. HOWEVER, ONLY EXPECTING DOWNDRAFTS OF 40-50 MILES PER HOUR AT THIS TIME. THE FREEZING LEVEL IS AROUND 15000, WHICH MAKES HAIL DIFFICULT, AND IF IT DOES FORM, IT SHOULD KEEP IT ON THE SMALL SIDE. AFTER TODAY, HIGH PRESSURE BEGINS TO BUILD TO THE EAST. THIS WILL TURN THE FLOW MORE TO THE SOUTHEAST TO EAST. WITH THIS CHANGE, MORE OF THE CONVECTIVE ACTIVITY WILL SHIFT FROM THE EASTERN INTERIOR, TO THE WESTERN INTERIOR AND GULF COAST. THIS WILL PERSIST WITH AFTERNOON SHOWERS AND THUNDERSTORMS IN THE AFORE MENTIONED AREA EACH AFTERNOON. IN THE OVERNIGHT HOURS, THERE WILL BE SOME MARITIME SHOWERS AND THUNDERSTORMS OVER THE ATLANTIC. SOME OF THESE MAY MAKE THEIR WAY ONSHORE, THE DISSIPATE OVER THE ATLANTIC METRO AREAS. AS THE WEEK PROGRESSES, AN UPPER LEVEL HIGH WILL DEVELOP AND STRENGTHEN OVER THE WESTERN ATLANTIC. THIS WILL KEEP THE EAST TO SOUTHEASTERLY FLOW OVER THE AREA, AS WELL AS, KEEP MOISTURE OVER SOUTH FLORIDA. THIS WILL KEEP SHOWERS AND THUNDERSTORMS IN THE FORECAST THE THE ENTIRE FORECAST PERIOD. AVIATION... A LINE OF ISOLATED SHOWERS AND THUNDERSTORMS STRETCH ACROSS THE ATLANTIC WATERS SOUTHWEST TO THE GULF WATERS. SOME OF THIS ACTIVITY MAY APPROACH KAPF AND KPBI OVER THE NEXT COUPLE OF HOURS BEFORE DISSIPATING...ALTHOUGH LEFT ANY VICINITY MENTION OUT OF TAFS FOR NOW. FOR THE REMAINDER OF THE PERIOD...DELAYED THE ONSET OF CONVECTION ACROSS THE EAST COAST SITES UNTIL 20Z AS MODEL REFLECTIVITIES DEPICT CONVECTIVE INITIATION MAINLY ACROSS THE INTERIOR. MARINE... WITH HURRICANE ARTHUR MOVING AWAY, MARINE CONDITIONS SHOULD CONTINUE TO IMPROVE. THERE WILL BE A 1 FOOT SWELL THROUGH THE DAY TODAY. THERE ALSO MAY BE SHOWERS AND THUNDERSTORMS ACROSS ALL SOUTH FLORIDA WATERS, MAINLY IN THE OVERNIGHT HOURS, FOR THE FORESEEABLE FUTURE. && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
1100 AM EDT FRI JUL 4 2014 ...SCATTERED AFTERNOON AND EARLY EVENING THUNDERSTORMS EXPECTED TO DEVELOP IN NORTH CENTRAL AND COASTAL NORTHEAST FLORIDA... .UPDATE... LATE MORNING SURFACE ANALYSIS DEPICTS HURRICANE ARTHUR CENTERED EAST OF THE VIRGINIA CAPES AND ACCELERATING NORTHEASTWARD. A TRAILING TROUGH FROM ARTHUR EXTENDS SOUTHWESTWARD ACROSS NORTHEAST FLORIDA THIS MORNING. ELEVATED MOISTURE VALUES ARE LOCATED ALONG AND SOUTHEAST OF THIS TROUGH AXIS...SHOWN VIA THE CONTRAST IN PRECIPITABLE WATER VAPOR (PWAT) VALUES WHEN COMPARING THE MORNING SOUNDINGS AT JACKSONVILLE (PWAT=1.96 INCHES) AND TALLAHASSEE (PWAT=1.35 INCHES). IN THE WAKE OF THE TROUGH...DEWPOINTS IN PORTIONS OF INTERIOR SOUTHEAST GEORGIA ARE FALLING INTO THE UPPER 50S...WHILE DEWPOINTS SOUTH AND EAST OF THE TROUGH AXIS ARE IN THE MID TO UPPER 70S AT LOCATIONS SUCH AS GAINESVILLE AND PALATKA. DRIER AIR WILL CONTINUE TO FILTER INTO SOUTHEAST GA AND THE SUWANNEE VALLEY AS THE DAY PROGRESSES...WHERE PLENTY OF INSOLATION WILL ALLOW HIGHS TO CLIMB INTO THE MID 90S. HIGH RESOLUTION GUIDANCE SUCH AS THE HRRR AND ARW INDICATE SCATTERED THUNDERSTORMS DEVELOPING ALONG THE TROUGH BEGINNING AROUND 18Z...GENERALLY FOR LOCATIONS FROM AMELIA ISLAND TO LAKE CITY AND POINTS SOUTH AND EASTWARD. WEAK WESTERLY STEERING FLOW WILL RESULT IN SLOW MOVEMENT OF THUNDERSTORMS...WITH A FEW STRONGER PULSE STORMS POSSIBLE IN COASTAL NORTHEAST FL AS ACTIVITY ENCOUNTERS THE ATLANTIC SEA BREEZE DURING THE LATE AFTERNOON...WHICH WILL LIKELY BE PINNED EAST OF INTERSTATE 95. GIVEN DRIER AIR MOVING IN ALOFT FROM THE NORTHWEST AND WEAK STEERING FLOW...GUSTY WINDS AND SLOW MOVING HEAVY DOWNPOURS ALONG WITH FREQUENT LIGHTNING STRIKES WILL BE THE PRIMARY THREATS TODAY. HIGHS IN NORTHEAST FLORIDA WILL LIKELY CLIMB INTO THE LOW TO MID 90S ALL THE WAY TO THE COAST BEFORE MID-AFTERNOON THUNDERSTORMS DEVELOP. ACTIVITY IN COASTAL ST. JOHNS/FLAGLER AND AREAS SOUTH OF GAINESVILLE MAY LINGER INTO THE EARLY EVENING HOURS BEFORE DISSIPATING BEFORE MIDNIGHT. && .AVIATION... MVFR CIGS MAY PERSIST THROUGH 16Z AT GNV...OTHERWISE...VFR CONDITIONS WILL PREVAIL THROUGH AT LEAST 18Z AT THE REGIONAL TERMINALS. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO IMPACT GNV AFTER 19Z...PRODUCING SUB-VFR CONDITIONS AND BRIEF WIND GUSTS UP TO 30 KNOTS. THUNDERSTORMS ARE POSSIBLE TOWARDS 20Z AT THE DUVAL COUNTY TERMINALS...AND WE WILL INCLUDE A TEMPO GROUP FOR JAX...CRG...AND VQQ IN THE 18Z TAF ISSUANCE FOR A PERIOD OF SUB- VFR CONDITIONS...LIKELY OCCURRING BETWEEN 20Z-24Z. VFR CONDITIONS WILL THEN PREVAIL REGION-WIDE TOWARDS 01Z. && .MARINE... CAUTION HEADLINES WERE DROPPED FOR THE OFFSHORE WATERS DURING THE MORNING FORECAST UPDATE. SEAS OFFSHORE WILL CONTINUE TO SUBSIDE TO 3-5 FEET THIS AFTERNOON AND 2-4 FEET TONIGHT. EXPECT SOUTHWEST WINDS OF 10-15 KNOTS THROUGH LATE AFTERNOON...FOLLOWED BY SCATTERED THUNDERSTORMS IMPACTING THE NORTHEAST FL WATERS DURING THE LATE AFTERNOON AND EARLY EVENING HOURS. RIP CURRENTS: MODERATE RISK CONTINUES DUE TO LONG PERIOD SWELLS GENERATED BY DEPARTING HURRICANE ARTHUR. && .PRELIMINARY POINT TEMPS/POPS... AMG 94 70 94 71 / 0 10 20 20 SSI 91 75 88 75 / 10 10 20 20 JAX 94 73 93 72 / 30 30 30 30 SGJ 91 74 89 74 / 50 50 30 30 GNV 92 70 93 71 / 50 30 40 40 OCF 91 71 92 71 / 50 40 40 40 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && $$ NELSON/SANDRIK/GUILLET
AREA FORECAST DISCUSSION
NWS MIAMI FL
1024 AM EDT FRI JUL 4 2014 .UPDATE... THERE WERE SOME CHANGES MADE TO THE SHORT TERM FORECAST FOR THIS AFTERNOON AND EARLY EVENING. THE FORECAST FOR THE EAST COAST METRO AREAS WAS UPDATED TO INCLUDE SCATTERED AFTERNOON/EARLY EVENING SHOWERS/THUNDERSTORMS. THE 12Z SOUNDING INDICATED A PWAT OF AROUND 1.9 INCHES. IN ADDITION THERE ARE LOW LEVEL SOUTHWESTERLY WINDS AND MID LEVEL WESTERLY WINDS. WITH THE EAST AND WEST COAST SEA BREEZES EXPECTED TODAY...INITIATION OF CONVECTION IS EXPECTED IN THE INTERIOR PORTIONS OF THE PENINSULA. BUT LATER IN THE AFTERNOON THE AFOREMENTIONED WESTERLY WINDS COULD HELP TO SHIFT SHOWERS/THUNDERSTORMS TOWARDS THE ATLANTIC COASTAL ZONE. THE LATEST GUIDANCE...INCLUDING THE LATEST HRRR MODEL...SUGGESTS THIS TREND AS WELL. SO SCATTERED SHOWERS/THUNDERSTORMS WERE ADDED TO THE ATLANTIC COAST METRO AREAS BUT MAINLY EXPECTED LATE AFTERNOON AND EARLY EVENING. THE 12Z SOUNDING ALSO INDICATED SOME LAYERS OF DRIER AIR IN THE MID LEVELS AND IN THE HAIL GROWTH ZONE SO SMALL HAIL IS POSSIBLE WITH THE STRONGER THUNDERSTORMS. IN ADDITION THERE COULD BE A SLIGHT RISK OF WATERSPOUTS ACROSS THE ATLANTIC WATERS AS THE LOW LEVEL WIND PROFILE IS FAVORABLE. 60 && .PREV DISCUSSION... /ISSUED 759 AM EDT FRI JUL 4 2014/ AVIATION... MOSTLY VFR IS EXPECTED TODAY WITH SCT TSRA AFT 19-20Z THIS AFTERNOON. LIGHT FLOW WILL GIVE WAY TO SEA BREEZES ALONG BOTH COASTS AROUND 17Z WITH CONVECTION DEVELOPING ALONG THE BOUNDARIES. THE STEERING FLOW IS ERRATIC THIS MORNING AND FORECAST SOUNDINGS SHOW SIMILAR CONDITIONS THROUGHOUT THE DAY. THUS, TSRA MOVEMENT WITH INTERACTIONS BETWEEN BOUNDARIES WILL BE SLOW AND ERRATIC SO ONLY PLACED VCTS IN THE FORECASTS AT THIS TIME BUT THERE COULD BE A BRIEF MVFR/IFR CIG/VSBY FAVORING THE EAST COAST TERMINALS AND WILL AMEND IF NECESSARY. KOB PREV DISCUSSION... /ISSUED 348 AM EDT FRI JUL 4 2014/ DISCUSSION... THE WEATHER PATTERN ACROSS SOUTH FLORIDA WILL BE INFLUENCED BY WEAK LOW PRESSURE TO THE NORTH. THIS WILL KEEP WEAK INSTABILITY OVER THE AREA FOR TODAY. GIVEN THE NOCTURNAL ACTIVITY OF TONIGHT, WILL KEEP SHOWERS AND THUNDERSTORMS IN THE FORECAST THROUGH THE DAY TODAY. LOOKING AT MODEL WINDS, THE STEERING FLOW IS FROM THE SOUTHWEST. IT DOES APPEAR THAT A GULF BREEZE WILL DEVELOP, TURNING THE WINDS SOMEWHAT MORE WESTERLY THIS AFTERNOON, FOR THE WESTERN HALF OF THE CWA. THE ATLANTIC SEA BREEZE SHOWS UP, BUT VERY WEAK AND DOES NOT LOOK AS THOUGH IT WILL BE ABLE TO PENETRATE TOO FAR INLAND, MOST LIKELY DUE TO THE SW FLOW. THIS MAKES THE BETTER CONVERGENCE AREA TO BE IN THE INTERIOR, WITH THE WESTERN INTERIOR AREAS OF BROWARD, PALM BEACH, AND MIAMI DADE COUNTIES, AS WELL AS THE EASTERN AREAS OF COLLIER, GLADES, AND HENDRY COUNTIES. HOWEVER, AS WITH MOST AFTERNOONS IN SOUTH FLORIDA, CAN NOT RULE OUT ANY LOCATION ACROSS THE AREA FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON. AS FOR THEIR INTENSITY, YESTERDAY LOOKED SOMEWHAT BETTER. TODAY, THE 500MB TEMP IS -6.8C. THE 700-500MB LAPSE RATE IS RIGHT AROUND 6 C/KM. THE NCAPE IS AROUND .15 AND CAPE IS LESS THAN 2000 JOULES. SO,. THIS ADDS UP TO MAINLY GARDEN VARIETY THUNDERSTORMS TODAY. THERE IS A DRY LAYER IN THE MID LEVELS THAT COLD HELP BRING A FEW STRONG DOWNBURSTS WITH ANY THUNDERSTORM THAT DEVELOPS. HOWEVER, ONLY EXPECTING DOWNDRAFTS OF 40-50 MILES PER HOUR AT THIS TIME. THE FREEZING LEVEL IS AROUND 15000, WHICH MAKES HAIL DIFFICULT, AND IF IT DOES FORM, IT SHOULD KEEP IT ON THE SMALL SIDE. AFTER TODAY, HIGH PRESSURE BEGINS TO BUILD TO THE EAST. THIS WILL TURN THE FLOW MORE TO THE SOUTHEAST TO EAST. WITH THIS CHANGE, MORE OF THE CONVECTIVE ACTIVITY WILL SHIFT FROM THE EASTERN INTERIOR, TO THE WESTERN INTERIOR AND GULF COAST. THIS WILL PERSIST WITH AFTERNOON SHOWERS AND THUNDERSTORMS IN THE AFORE MENTIONED AREA EACH AFTERNOON. IN THE OVERNIGHT HOURS, THERE WILL BE SOME MARITIME SHOWERS AND THUNDERSTORMS OVER THE ATLANTIC. SOME OF THESE MAY MAKE THEIR WAY ONSHORE, THE DISSIPATE OVER THE ATLANTIC METRO AREAS. AS THE WEEK PROGRESSES, AN UPPER LEVEL HIGH WILL DEVELOP AND STRENGTHEN OVER THE WESTERN ATLANTIC. THIS WILL KEEP THE EAST TO SOUTHEASTERLY FLOW OVER THE AREA, AS WELL AS, KEEP MOISTURE OVER SOUTH FLORIDA. THIS WILL KEEP SHOWERS AND THUNDERSTORMS IN THE FORECAST THE THE ENTIRE FORECAST PERIOD. AVIATION... A LINE OF ISOLATED SHOWERS AND THUNDERSTORMS STRETCH ACROSS THE ATLANTIC WATERS SOUTHWEST TO THE GULF WATERS. SOME OF THIS ACTIVITY MAY APPROACH KAPF AND KPBI OVER THE NEXT COUPLE OF HOURS BEFORE DISSIPATING...ALTHOUGH LEFT ANY VICINITY MENTION OUT OF TAFS FOR NOW. FOR THE REMAINDER OF THE PERIOD...DELAYED THE ONSET OF CONVECTION ACROSS THE EAST COAST SITES UNTIL 20Z AS MODEL REFLECTIVITIES DEPICT CONVECTIVE INITIATION MAINLY ACROSS THE INTERIOR. MARINE... WITH HURRICANE ARTHUR MOVING AWAY, MARINE CONDITIONS SHOULD CONTINUE TO IMPROVE. THERE WILL BE A 1 FOOT SWELL THROUGH THE DAY TODAY. THERE ALSO MAY BE SHOWERS AND THUNDERSTORMS ACROSS ALL SOUTH FLORIDA WATERS, MAINLY IN THE OVERNIGHT HOURS, FOR THE FORESEEABLE FUTURE. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 89 78 88 77 / 40 30 20 20 FORT LAUDERDALE 89 80 87 79 / 30 30 20 20 MIAMI 90 79 88 78 / 30 30 20 20 NAPLES 89 79 87 78 / 20 20 20 20 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...30/KOB LONG TERM....60/BD
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NWS MELBOURNE FL
900 AM EDT FRI JUL 4 2014 .DISCUSSION... ...SCATTERED STORMS MOVING EASTWARD THIS AFTERNOON AND EVENING... REGIONAL SOUNDINGS THIS MORNING YIELDED A DEEP RELATIVELY MOIST PROFILE WITH PWATS INVOF 2 INCHES ACROSS CENTRAL FL. THE SOUTHERN PORTION OF THE STATE IS SLIGHTLY DRIER AS EVIDENCED BY WV IMAGERY AND THE GPS SATELLITE ESTIMATE. A SEASONALLY FAVORABLE REGIME (DEEP SW FLOW) ALONG WITH AMPLE SFC HEATING WL LEAD TO RATHER EARLY ONSET OF EASTWARD MOVING SHOWERS AND STORMS. 3KM HRRR DERIVED REFLECTIVITY IMAGERY SHOWS THE INITIAL PCPN ASCD WITH AN EASTWARD GULF BOUNDARY WL LEAD TO SCT SHRA/TS MOVING ACROSS THE I-4 CORRIDOR EARLY THIS AFTN AND SPREADING EAST ACROSS THE ECFL AREA FROM EARLY THROUGH MID AFTERNOON. ACTIVITY WL BE ENHANCED BY MID LVL VORTICITY/SHEAR AXIS CONTINUES ALONG TO JUST NORTH OF THE FORECAST AREA AND A HIGH COVERAGE COVERAGE OF SCATTERED STORMS ACROSS NRN/CENTRAL SECTIONS IS ANTICIPATED. TEMPS AT H5 ARE A LITTLE ABOVE NORMAL...SO THE MAIN HAZARDS WOULD BE LOCALLY HEAVY RAIN...FREQUENT LIGHTNING AND WIND GUSTS TO 50 MPH WITH A FEW WET MICROBURSTS POSSIBLE. STORMS WILL MOVE NE ACROSS NRN SECTIONS WITH THE MID LYR SW FLOW BY MID-LATE AFTERNOON WITH STORMS REACHING THE INTRACOASTAL AND NEAR SHORE WATERS NORTH OF SEBASTIAN INLET. && .AVIATION...(FROM PREVIOUS) SCT TSRA WITH MVFR CIGS AND IFR VSBYS ARE FORECAST TO DEVELOP BY 18Z AND AFFECT NRN TERMINALS BTWN 19Z-22Z. SW STEERING FLOW WILL BRING STORMS TOWARD THE COAST FROM KDAB-KMLB IN THE MID TO LATE AFTERNOON. FOR SRN TERMINALS...ISOLD CONVECTION MAY DEVELOP ALONG THE EAST COAST SEA BREEZE BY EARLY TO MID AFTN WITH A SLIGHTLY HIGHER TSRA CHC IN THE LATE AFTN. SOME CONVECTION WILL LINGER INTO THE EVENING...HAVE INCLUDED VCTS 00Z-03Z...MAINLY NRN TERMINALS. && .MARINE...S-SW WINDS TO 10-15 KNOTS OFFSHORE WITH SEAS 2-3 FT NEAR SHORE AND UP TO 3-4 FT OFFSHORE THIS MORNING. SCATTERED TSTMS WILL APPROACH FROM THE WEST IN THE MID TO LATE AFTERNOON AND CONTINUING INTO THE EVENING POSING A HAZARD FOR BOATERS ON THIS INDEPENDENCE DAY. SAT-TUE...FAVORABLE BOATING CONDITIONS EXPECTED ACROSS THE WATERS THIS WEEKEND INTO EARLY NEXT WEEK WITH HIGH PRESSURE RIDGE BUILDING BACK NORTH ACROSS CENTRAL FLORIDA AND PERSISTING OVER THE REGION. WINDS TO REMAIN BELOW 15 KNOTS OUT OF THE S/SW OVERNIGHT...BECOMING S/SE DURING THE DAY AS SEA BREEZE DEVELOPS AND MOVES INLAND EACH AFTERNOON. SEAS WILL RANGE BETWEEN 1-2 FEET NEARSHORE AND 2-3 FEET OFFSHORE. && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ PUBLIC/MARINE/AVIATION...JP RADAR/IMPACT WEATHER...RL
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
608 AM EDT FRI JUL 4 2014 .SYNOPSIS... HIGH PRESSURE CENTERED OVER THE MIDWEST TODAY WILL BE IN THE CENTRAL APPALACHIANS SATURDAY. THE HIGH WILL CIRCULATE DRY AIR INTO THE FORECAST AREA. && .NEAR TERM /THROUGH TONIGHT/... DRYING WILL OCCUR BEHIND THE COLD FRONT TODAY. THE MODELS INDICATED MID-LEVEL CAPPING. THE NAM AND GFS MOS POPS WERE LESS THAN 10 PERCENT. THE 06Z HRRR AND 00Z SPC WRF DISPLAYED JUST ISOLATED SHOWERS. MAINTAINED THE FORECAST OF POPS LESS THAN 10 PERCENT. USED THE WARMER HIGH TEMPERATURE GUIDANCE BECAUSE WE WILL GET OFF TO A RELATIVELY WARM START AND RECENT VERIFICATION. THE LOW TEMPERATURE GUIDANCE WAS CONSISTENT. && .SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/... HIGH PRESSURE TO THE NORTH WILL CIRCULATE DRY AIR INTO THE FORECAST AREA. THE MODELS INDICATED MID-LEVEL CAPPING CONTINUING. ALL OF THE NAM AND GFS MOS POPS WERE LESS THAN 10 PERCENT. MAINTAINED THE DRY FORECAST. LEANED TOWARD THE WARMER MAV MOS HIGH TEMPERATURE GUIDANCE BECAUSE IT HAS BEEN MORE CONSISTENT. THE LOW TEMPERATURE GUIDANCE WAS CLOSE. && .LONG TERM /SUNDAY THROUGH THURSDAY/... THE GFS AND ECMWF DISPLAYED A WEAKNESS IN THE UPPER RIDGING WITH TROUGHING BECOMING MORE PRONOUNCED TOWARD THE END OF THE MEDIUM- RANGE PERIOD. THE MODELS SHOWED SURFACE PRESSURE RIDGING SOUTH AND EAST OF OUR AREA WITH SOME LEE-SIDE TROUGHING HERE. THE PATTERN SUPPORTS SCATTERED MAINLY DIURNAL THUNDERSTORMS. THE GFS...ECMWF... AND EKD MOS HAD POPS OF 10 TO 30 PERCENT WITH THE HIGHER VALUES TOWARD THE END OF THE PERIOD. THE GUIDANCE INDICATED HIGH TEMPERATURES NEAR CLIMATOLOGY EARLY IN THE PERIOD WITH READINGS SEVERAL DEGREES ABOVE NORMAL BEGINNING TUESDAY. && .AVIATION /10Z FRIDAY THROUGH TUESDAY/... MAINLY VFR CONDITIONS EXPECTED THROUGH THE PERIOD. HURRICANE ARTHUR CONTINUES TO MOVE NORTHEAST AND IS NOW OFF THE VIRGINIA CAPES. A WEAK COLD FRONT IS MOVING THROUGH THE AREA THIS MORNING. DRIER AIR BEHIND THE FRONT...ALONG WITH SUBSIDENCE IN THE WAKE OF HURRICANE ARTHUR...SHOULD LEAD TO A GENERALLY DRY DAY TODAY. GOOD LOW-LEVEL MIXING IS DETERRING FOG FORMATION THIS MORNING. EXPECT MAINLY SOME AFTERNOON CU WITH DAYTIME HEATING LATER TODAY AND WINDS GENERALLY FROM THE NORTH AT 5 TO 10 KTS...SHIFTING TO THE NE BY THIS EVENING. EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS TO AVIATION EXPECTED THROUGH MONDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
647 PM CDT SAT JUL 5 2014 .UPDATE... ISSUED AT 644 PM CDT SAT JUL 5 2014 WILL MAKE A QUICK UPDATED TO ADJUST THE PRECIPITATION THIS EVENING. THUNDERSTORMS NOT FORMING ON THE OUTFLOW AS EXPECTED...SO LOWERED POPS. && .SHORT TERM /TONIGHT/... ISSUED AT 312 PM CDT SAT JUL 5 2014 MCV/MCS CURRENTLY EXITING THE AREA TO THE SOUTHEAST THIS AFTERNOON. TEMPS HAVE BEEN HELD BACK BUT ARE RECOVERING ACROSS THE WEST. WARM FRONT OVER NORTHERN MO THIS MORNING HAS BEEN REINFORCED BY OUTFLOW BOUNDARY FROM MESOSCALE SYSTEM...BUT SHOULD BEGIN TO LIFT NORTH DURING THE NIGHTTIME HOURS. MODELS AT ODDS ABOUT CONVECTION COVERAGE TONIGHT...BUT HINTING AT SOME DEVELOPMENT ALONG THE EDGE OF THE RETREATING WARM FRONT/OUTFLOW BOUNDARY THROUGH IOWA OVERNIGHT. WEAKEST PORTION OF THE H700 CAP FAVORS THE EASTERN AND SOUTHERN SECTIONS. HRRR REFLECTS SOME DEVELOPMENT WITH A BAND OF STORMS FORMING AFT 04Z NEAR I80 CORRIDOR...VARIOUS OTHER SOLUTIONS ALSO FAVOR SOME DEVELOPMENT OVER THE EAST OR ALONG THE IOWA/MO BORDER BETWEEN 00 AND 06Z AS NOCTURNAL LOW LEVEL JET INCREASES AND IMPINGES ALONG THE WARM FRONT/OUTFLOW BOUNDARY. WILL INCREASE POPS AGAIN BY MID TO LATE EVENING OVER THE EAST AND SOUTH...WEAK STEERING CURRENTS SUGGEST SOME SOUTHEASTERLY DRIFT ALONG THE BOUNDARY OVERNIGHT. ONCE AGAIN...IF CONVECTION GETS A BIT MORE ORGANIZED COULD SEE A QUICK INCH OR TWO TOTAL FROM ANY STRONGER CELLS THAT DEVELOP. WARM CLOUD DEPTHS PUSHING 13-14KFT AND PRECIPITABLE WATER STILL RUNNING 1.5 INCHES OVER THE SOUTHEAST THIRD. FOR NOW WILL NOT ISSUE HEADLINES AS COVERAGE IS EXPECTED TO BE LIMITED. AFTER LAST NIGHTS/THIS MORNING RAINFALL... GRIDDED FLASH FLOOD GUIDANCE HAS LOWERED TO 1 TO 1.5 INCHES OVER A GOOD SHARE OF THE SOUTH WITH 3 HOURLY GUIDANCE NEARING 2 INCHES OVER THE SAME LOCATIONS. THE SOUTHERN TWO TIER COUNTIES CONTINUE HIGHER...WITH 2 INCH VALUES FOR 1 HOUR AND 2 TO 3 INCH VALUES FOR 3 HOUR GUIDANCE. NEEDLESS TO SAY...NOT MUCH CAPACITY LEFT IN SOIL FOR ADDITIONAL RAINFALL OVER THE NEXT FEW DAYS. LOWS WILL CREEP UP TONIGHT. DESPITE THE LACK OF MUCH SUNSHINE THIS AFTERNOON...LOWS WILL REMAIN IN THE MID TO UPPER 60S AS DEW POINTS HAVE RISEN WITH THE RETURN OF MOISTURE TO THE AREA. .LONG TERM /SUNDAY THROUGH SATURDAY/... ISSUED AT 312 PM CDT SAT JUL 5 2014 LONG TERM FORECAST PERIOD WILL FEATURE RATHER ACTIVE WX AND AN OVERALL UPPER AIR PATTERN OF WESTERLIES INVOF OF IOWA...EVOLVING FROM BROAD NORTHWEST FLOW TO BROAD CYCLONIC FLOW. MAIN CHALLENGES EARLY IN THE PERIOD WILL BE TSRA CHANCES SUNDAY AFTN/EVE AS WELL AS LATE MONDAY INTO TUE. FCST PERIOD BEGINS WITH IOWA SOUTH OF THE WESTERLIES. SUNDAY IS EXPECTED TO BE MORE SUMMER-LIKE...WITH THERMAL RIDGING AND MOISTURE TRANSPORT RESULTING IN SEASONALLY HOT AND HUMID CONDITIONS. TEMPS RANGING FROM THE UPPER 80S TO MIDDLE 90S ALONG WITH DEWPOINTS IN THE 70S ARE EXPECTED. AN IMPULSE WILL SWEEP A COOL FRONT INTO THE STATE ON SUNDAY. QUESTION IS HOW FAR WEST ALONG THE FRONT WILL THE TSRA DEVELOP. ALTHOUGH INSTABILITY IS PROGGED TO BE RESPECTABLE...CAPPING WILL INCREASE TOWARD THE WEST ACROSS THE STATE. BEST CHANCES OF TSRA WILL BE IN EASTERN IOWA...WHERE THE CAP WILL BE WEAKER AND UPPER-LEVEL FORCING WILL BE STRONGER. LOW- LEVEL JET WILL INCREASE MOISTURE TRANSPORT BY LATE EVENING...SO HAVE BROUGHT CHANCE POPS ALONG THE SOUTHERN BORDER OF THE STAGE BY THAT TIME. FRONT IS EXPECTED TO BECOME QUASI-STATIONARY INVOF THE IA-MO BORDER BY LATE SUNDAY NIGHT. STRONGER H5 SHORTWAVE WILL BRING ANOTHER CHANCE OF TSRA BY LATE MON. BOTH THERMODYNAMIC AND KINEMATIC FORCING WILL BE STRONGER WITH THIS SYSTEM THAN THE ONE ON LATE SUN. THIS SHORTWAVE WILL PUSH ANOTHER COOL FRONT SOUTH THROUGH IOWA...EVENTUALLY OVERTAKING THE QUASI-STATIONARY BOUNDARY INVOF THE IA-MO BORDER. AMPLE INSTABILITY AHEAD OF THE ADVANCING FRONT IS EXPECTED TO PROMOTE SFC-BASED TSRA DEVELOPMENT. SHEAR PARAMETERS SUGGEST A FEW SUPERCELLS POSSIBLE EARLY WITH LARGE HAIL AND DAMAGING WINDS THE MAIN THREATS...BUT CANNOT RULE OUT AN ISOLATED TORNADO. THE CONVECTION IS EXPECTED TO GROW UPSCALE INTO AN MCS AND PUSH SOUTHEAST INTO THE EVENING. AFTER THE FROPA MONDAY NIGHT/TUE MORNING...CYCLONIC WESTERLIES WILL DOMINATE THE WX INTO LATER IN THE WEEK. NEXT CHANCE OF PCPN WILL ARRIVE THURSDAY INTO THURSDAY NIGHT AS A WEAK IMPULSE PASSES OVER THE REGION. THE 12Z ECMWF IS ADVERTISING A STRONGER SHORTWAVE BRINGING ANOTHER BOUNDARY THROUGH THE CWA ON SATURDAY. THE 12Z RUN WAS CONSISTENT IN THIS REGARD WITH THE 00Z RUN. THIS SOLUTION IS ADMITTEDLY DIFFERENT THAN LAST NIGHT/S LONG TERM PACKAGE WHICH KEPT THE ACTIVITY NORTH OF THE CWA. SHRA/TSRA WILL BE POSSIBLE WITH THIS BOUNDARY AS IT SWEEPS THROUGH THE CWA. THIS BOUNDARY WILL BRING A SLIGHTLY COOLER AIR MASS OVER THE CWA TO END THE WEEKEND. && .AVIATION...06/00Z ISSUED AT 611 PM CDT SAT JUL 5 2014 BOUNDARY FROM SOUTHEAST NEBRASKA ACROSS NORTHERN MO WILL LIFT SLOWLY OVERNIGHT AND LIFT NORTH ON SUNDAY. WIDESPREAD MFR AND IFR STRATUS DEVELOPING TONIGHT INTO SUNDAY MORNING. MVFR FOG CONDITIONS EXPECTED AS WELL. VFR BY LATE SUNDAY MORNING. COLD FRONT WILL MOVE INTO THE STATE SUNDAY AFTERNOON. AT THIS TIME OPTED TO PUT IN VCTS OVER THE NERN TAF SITES. FEEL CAPPING WILL HOLD THUNDERSTORM CHANCES UNTIL LATE IN THE PERIOD...BUT WILL BE MONITORED. OUTLOOK...THUNDERSTORMS WILL LIKELY BECOME NUMEROUS OVER THE NERN HALF OF THE STATE SUNDAY NIGHT...SCATTERED SOUTHWEST. ANOTHER COLD FRONT WILL MOVE INTO THE STATE BY TUE...WITH ANOTHER ROUND OF THUNDERSTORMS EXPECTED MONDAY NIGHT. HIGH PRESSURE WILL BRING FAIR WEATHER FOR WEDNESDAY AND THURSDAY. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...MS JUL 14 SHORT TERM...REV LONG TERM...ZOGG AVIATION...MS JUL 14
AREA FORECAST DISCUSSION
NWS DES MOINES IA
617 PM CDT SAT JUL 5 2014 .SHORT TERM /TONIGHT/... ISSUED AT 312 PM CDT SAT JUL 5 2014 MCV/MCS CURRENTLY EXITING THE AREA TO THE SOUTHEAST THIS AFTERNOON. TEMPS HAVE BEEN HELD BACK BUT ARE RECOVERING ACROSS THE WEST. WARM FRONT OVER NORTHERN MO THIS MORNING HAS BEEN REINFORCED BY OUTFLOW BOUNDARY FROM MESOSCALE SYSTEM...BUT SHOULD BEGIN TO LIFT NORTH DURING THE NIGHTTIME HOURS. MODELS AT ODDS ABOUT CONVECTION COVERAGE TONIGHT...BUT HINTING AT SOME DEVELOPMENT ALONG THE EDGE OF THE RETREATING WARM FRONT/OUTFLOW BOUNDARY THROUGH IOWA OVERNIGHT. WEAKEST PORTION OF THE H700 CAP FAVORS THE EASTERN AND SOUTHERN SECTIONS. HRRR REFLECTS SOME DEVELOPMENT WITH A BAND OF STORMS FORMING AFT 04Z NEAR I80 CORRIDOR...VARIOUS OTHER SOLUTIONS ALSO FAVOR SOME DEVELOPMENT OVER THE EAST OR ALONG THE IOWA/MO BORDER BETWEEN 00 AND 06Z AS NOCTURNAL LOW LEVEL JET INCREASES AND IMPINGES ALONG THE WARM FRONT/OUTFLOW BOUNDARY. WILL INCREASE POPS AGAIN BY MID TO LATE EVENING OVER THE EAST AND SOUTH...WEAK STEERING CURRENTS SUGGEST SOME SOUTHEASTERLY DRIFT ALONG THE BOUNDARY OVERNIGHT. ONCE AGAIN...IF CONVECTION GETS A BIT MORE ORGANIZED COULD SEE A QUICK INCH OR TWO TOTAL FROM ANY STRONGER CELLS THAT DEVELOP. WARM CLOUD DEPTHS PUSHING 13-14KFT AND PRECIPITABLE WATER STILL RUNNING 1.5 INCHES OVER THE SOUTHEAST THIRD. FOR NOW WILL NOT ISSUE HEADLINES AS COVERAGE IS EXPECTED TO BE LIMITED. AFTER LAST NIGHTS/THIS MORNING RAINFALL... GRIDDED FLASH FLOOD GUIDANCE HAS LOWERED TO 1 TO 1.5 INCHES OVER A GOOD SHARE OF THE SOUTH WITH 3 HOURLY GUIDANCE NEARING 2 INCHES OVER THE SAME LOCATIONS. THE SOUTHERN TWO TIER COUNTIES CONTINUE HIGHER...WITH 2 INCH VALUES FOR 1 HOUR AND 2 TO 3 INCH VALUES FOR 3 HOUR GUIDANCE. NEEDLESS TO SAY...NOT MUCH CAPACITY LEFT IN SOIL FOR ADDITIONAL RAINFALL OVER THE NEXT FEW DAYS. LOWS WILL CREEP UP TONIGHT. DESPITE THE LACK OF MUCH SUNSHINE THIS AFTERNOON...LOWS WILL REMAIN IN THE MID TO UPPER 60S AS DEW POINTS HAVE RISEN WITH THE RETURN OF MOISTURE TO THE AREA. .LONG TERM /SUNDAY THROUGH SATURDAY/... ISSUED AT 312 PM CDT SAT JUL 5 2014 LONG TERM FORECAST PERIOD WILL FEATURE RATHER ACTIVE WX AND AN OVERALL UPPER AIR PATTERN OF WESTERLIES INVOF OF IOWA...EVOLVING FROM BROAD NORTHWEST FLOW TO BROAD CYCLONIC FLOW. MAIN CHALLENGES EARLY IN THE PERIOD WILL BE TSRA CHANCES SUNDAY AFTN/EVE AS WELL AS LATE MONDAY INTO TUE. FCST PERIOD BEGINS WITH IOWA SOUTH OF THE WESTERLIES. SUNDAY IS EXPECTED TO BE MORE SUMMER-LIKE...WITH THERMAL RIDGING AND MOISTURE TRANSPORT RESULTING IN SEASONALLY HOT AND HUMID CONDITIONS. TEMPS RANGING FROM THE UPPER 80S TO MIDDLE 90S ALONG WITH DEWPOINTS IN THE 70S ARE EXPECTED. AN IMPULSE WILL SWEEP A COOL FRONT INTO THE STATE ON SUNDAY. QUESTION IS HOW FAR WEST ALONG THE FRONT WILL THE TSRA DEVELOP. ALTHOUGH INSTABILITY IS PROGGED TO BE RESPECTABLE...CAPPING WILL INCREASE TOWARD THE WEST ACROSS THE STATE. BEST CHANCES OF TSRA WILL BE IN EASTERN IOWA...WHERE THE CAP WILL BE WEAKER AND UPPER-LEVEL FORCING WILL BE STRONGER. LOW- LEVEL JET WILL INCREASE MOISTURE TRANSPORT BY LATE EVENING...SO HAVE BROUGHT CHANCE POPS ALONG THE SOUTHERN BORDER OF THE STAGE BY THAT TIME. FRONT IS EXPECTED TO BECOME QUASI-STATIONARY INVOF THE IA-MO BORDER BY LATE SUNDAY NIGHT. STRONGER H5 SHORTWAVE WILL BRING ANOTHER CHANCE OF TSRA BY LATE MON. BOTH THERMODYNAMIC AND KINEMATIC FORCING WILL BE STRONGER WITH THIS SYSTEM THAN THE ONE ON LATE SUN. THIS SHORTWAVE WILL PUSH ANOTHER COOL FRONT SOUTH THROUGH IOWA...EVENTUALLY OVERTAKING THE QUASI-STATIONARY BOUNDARY INVOF THE IA-MO BORDER. AMPLE INSTABILITY AHEAD OF THE ADVANCING FRONT IS EXPECTED TO PROMOTE SFC-BASED TSRA DEVELOPMENT. SHEAR PARAMETERS SUGGEST A FEW SUPERCELLS POSSIBLE EARLY WITH LARGE HAIL AND DAMAGING WINDS THE MAIN THREATS...BUT CANNOT RULE OUT AN ISOLATED TORNADO. THE CONVECTION IS EXPECTED TO GROW UPSCALE INTO AN MCS AND PUSH SOUTHEAST INTO THE EVENING. AFTER THE FROPA MONDAY NIGHT/TUE MORNING...CYCLONIC WESTERLIES WILL DOMINATE THE WX INTO LATER IN THE WEEK. NEXT CHANCE OF PCPN WILL ARRIVE THURSDAY INTO THURSDAY NIGHT AS A WEAK IMPULSE PASSES OVER THE REGION. THE 12Z ECMWF IS ADVERTISING A STRONGER SHORTWAVE BRINGING ANOTHER BOUNDARY THROUGH THE CWA ON SATURDAY. THE 12Z RUN WAS CONSISTENT IN THIS REGARD WITH THE 00Z RUN. THIS SOLUTION IS ADMITTEDLY DIFFERENT THAN LAST NIGHT/S LONG TERM PACKAGE WHICH KEPT THE ACTIVITY NORTH OF THE CWA. SHRA/TSRA WILL BE POSSIBLE WITH THIS BOUNDARY AS IT SWEEPS THROUGH THE CWA. THIS BOUNDARY WILL BRING A SLIGHTLY COOLER AIR MASS OVER THE CWA TO END THE WEEKEND. && .AVIATION...06/00Z ISSUED AT 611 PM CDT SAT JUL 5 2014 BOUNDARY FROM SOUTHEAST NEBRASKA ACROSS NORTHERN MO WILL LIFT SLOWLY OVERNIGHT AND LIFT NORTH ON SUNDAY. WIDESPREAD MFR AND IFR STRATUS DEVELOPING TONIGHT INTO SUNDAY MORNING. MVFR FOG CONDITIONS EXPECTED AS WELL. VFR BY LATE SUNDAY MORNING. COLD FRONT WILL MOVE INTO THE STATE SUNDAY AFTERNOON. AT THIS TIME OPTED TO PUT IN VCTS OVER THE NERN TAF SITES. FEEL CAPPING WILL HOLD THUNDERSTORM CHANCES UNTIL LATE IN THE PERIOD...BUT WILL BE MONITORED. OUTLOOK...THUNDERSTORMS WILL LIKELY BECOME NUMEROUS OVER THE NERN HALF OF THE STATE SUNDAY NIGHT...SCATTERED SOUTHWEST. ANOTHER COLD FRONT WILL MOVE INTO THE STATE BY TUE...WITH ANOTHER ROUND OF THUNDERSTORMS EXPECTED MONDAY NIGHT. HIGH PRESSURE WILL BRING FAIR WEATHER FOR WEDNESDAY AND THURSDAY. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...REV LONG TERM...ZOGG AVIATION...MS JUL 14
AREA FORECAST DISCUSSION
NWS TOPEKA KS
957 PM CDT Sat Jul 5 2014 ...Updated for short term thunderstorm chances... .UPDATE... Issued at 950 PM CDT SAT JUL 5 2014 Short term models (HRRR, RAP13) continue to try to develop convection over eastern Kansas this evening, and it continues to not develop to this point. New NAM not as aggressive as previous two runs, but still has spotty precip and more persistent precip in east central KS through tonight. Water vapor imagery showing one mid- level shortwave trough move southeastward across central and eastern KS, and weak subsidence behind it may be helping to suppress evening convection in KS. Models do have postive theta-e advection in the 850 to 700 mb layer for later this evening through 1 AM, so have not removed POPs from eastern KS, but have dropped them for north central KS for tonight. Any thunderstorms that do form will obviously have the potential for heavy rain with precipitable water values near 2" and decent moisture transport evident at 850 mb. && .SHORT TERM...(This Evening through Sunday) Issued at 244 PM CDT SAT JUL 5 2014 Forecast today quickly challenged with mesoscale conditions as convective complex moved across eastern Nebraska in the early morning hours. An outflow boundary then moved southwest into northeast Kansas, through about Topeka to just east of Marysville. As southwesterly surface winds have strengthened through the day, they have worked to counter slightly reinforced outflow and push this boundary back to the north. Little progress was made on the east end, and appears as though the incoming upper shortwave evident on WV imagery will move across this boundary for the remainder of the afternoon and evening hours. While shear is not ideal, and high surface dewpoints not conducive for a high end wind threat, there is enough instability (2000-3000J/kg range) to consider hail and possibly locally heavy rainfall a threat if these storms develop and move through. Forecast is certainly probabilistic - GFS confines convection more east, as does the EC, although the EC is slower with its exit through the morning on Sunday. The HRRR and NAM extend area of convection farther westward from NE KS and drop cluster of precip south southeast across the area through the evening hours. Have played the forecast toward the latter, although kept coverage isolated in nature as it passes through. Can`t rule out a bust with precip, especially as you go west, but do think the far eastern counties will see hit and miss showers and thunderstorms as the evening goes on. Heat returns on Sunday as mid level temperatures climb under the shortwave ridge behind the departing shortwave trof. Have highs in the 90s with heat indices coming out in the 99-103 range as the dewpoints hold around 70 east to the 60s west...however western counties are hotter so in the end heat index differences are subtle at best. .LONG TERM...(Sunday Night through Saturday) Issued at 244 PM CDT SAT JUL 5 2014 By Sunday evening the cold front dips southward from central NE, straddling the KS and NE border near 00Z. The main upper trough positioned to our north and east at this time has given guidance lower confidence in precip developing near the weakly convergent frontal boundary until after midnight. Northern areas of the CWA have a slight chance for thunderstorms while most of the CWA remains dry. Monday afternoon will be another hot and humid day as the surface trough over western KS deepens, increasing southwesterly flow and mixing of warmer air aloft. Highs once again in the mid to upper 90s are likely with heat indices between 100 and 103 degrees. A more potent shortwave trough digs southward through the plains on Monday evening, shunting the cold front through the CWA by 18Z Tuesday. Showers and thunderstorms are likely across the Nebraska and northwest MO border, decreasing to a chance further south as the heavier precip bands follow the upper trough axis centered over central/northern MO. Wind shear through 6 KM increases overnight with the passing wave between 30 and 40 kts while MLCAPE is around 1500 J/KG. A few stronger storms cannot be ruled out, especially if they redevelop or are able to become sfc based in the afternoon. Winds shift back towards the south with another incoming upper wave expected Wednesday evening. Trends show the heavier precip bands to impact mainly north central and portions of central KS where highest pops were placed. Precipitation will wane as it lifts northeast through Thursday, replaced by temporary ridging on Friday. Saturday begins the unsettled pattern once again as northwest flow begins to bring another series of weak disturbances through the region. Highs behind the boundary Tuesday through Thursday will cool back to the 80s with lows in the upper 60s. Increased warm advection Friday and Saturday, raise temps once again to the 90s accompanied by lows in the 70s. && .AVIATION...(For the 00Z TAFs through 00Z Sunday Evening) Issued at 648 PM CDT SAT JUL 5 2014 Would expect VFR through period, except if thunderstorms develop and move across TAF sites. Right now expect a gradual decrease in southerly winds through the evening, then a chance of thunderstorms developing in northeast KS/southeast Nebraska in the next couple hours. These thunderstorms could move across TOP and FOE in the 02Z to 07Z time frame, but confidence is not high. MHK has a lesser chance and have left any indicator out at this time. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GDP SHORT TERM...67 LONG TERM...Bowen AVIATION...GDP
AREA FORECAST DISCUSSION
NWS TOPEKA KS
651 PM CDT Sat Jul 5 2014 ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Sunday) Issued at 244 PM CDT SAT JUL 5 2014 Forecast today quickly challenged with mesoscale conditions as convective complex moved across eastern Nebraska in the early morning hours. An outflow boundary then moved southwest into northeast Kansas, through about Topeka to just east of Marysville. As southwesterly surface winds have strengthened through the day, they have worked to counter slightly reinforced outflow and push this boundary back to the north. Little progress was made on the east end, and appears as though the incoming upper shortwave evident on WV imagery will move across this boundary for the remainder of the afternoon and evening hours. While shear is not ideal, and high surface dewpoints not conducive for a high end wind threat, there is enough instability (2000-3000J/kg range) to consider hail and possibly locally heavy rainfall a threat if these storms develop and move through. Forecast is certainly probabilistic - GFS confines convection more east, as does the EC, although the EC is slower with its exit through the morning on Sunday. The HRRR and NAM extend area of convection farther westward from NE KS and drop cluster of precip south southeast across the area through the evening hours. Have played the forecast toward the latter, although kept coverage isolated in nature as it passes through. Can`t rule out a bust with precip, especially as you go west, but do think the far eastern counties will see hit and miss showers and thunderstorms as the evening goes on. Heat returns on Sunday as mid level temperatures climb under the shortwave ridge behind the departing shortwave trof. Have highs in the 90s with heat indices coming out in the 99-103 range as the dewpoints hold around 70 east to the 60s west...however western counties are hotter so in the end heat index differences are subtle at best. .LONG TERM...(Sunday Night through Saturday) Issued at 244 PM CDT SAT JUL 5 2014 By Sunday evening the cold front dips southward from central NE, straddling the KS and NE border near 00Z. The main upper trough positioned to our north and east at this time has given guidance lower confidence in precip developing near the weakly convergent frontal boundary until after midnight. Northern areas of the CWA have a slight chance for thunderstorms while most of the CWA remains dry. Monday afternoon will be another hot and humid day as the surface trough over western KS deepens, increasing southwesterly flow and mixing of warmer air aloft. Highs once again in the mid to upper 90s are likely with heat indices between 100 and 103 degrees. A more potent shortwave trough digs southward through the plains on Monday evening, shunting the cold front through the CWA by 18Z Tuesday. Showers and thunderstorms are likely across the Nebraska and northwest MO border, decreasing to a chance further south as the heavier precip bands follow the upper trough axis centered over central/northern MO. Wind shear through 6 KM increases overnight with the passing wave between 30 and 40 kts while MLCAPE is around 1500 J/KG. A few stronger storms cannot be ruled out, especially if they redevelop or are able to become sfc based in the afternoon. Winds shift back towards the south with another incoming upper wave expected Wednesday evening. Trends show the heavier precip bands to impact mainly north central and portions of central KS where highest pops were placed. Precipitation will wane as it lifts northeast through Thursday, replaced by temporary ridging on Friday. Saturday begins the unsettled pattern once again as northwest flow begins to bring another series of weak disturbances through the region. Highs behind the boundary Tuesday through Thursday will cool back to the 80s with lows in the upper 60s. Increased warm advection Friday and Saturday, raise temps once again to the 90s accompanied by lows in the 70s. && .AVIATION...(For the 00Z TAFs through 00Z Sunday Evening) Issued at 648 PM CDT SAT JUL 5 2014 Would expect VFR through period, except if thunderstorms develop and move across TAF sites. Right now expect a gradual decrease in southerly winds through the evening, then a chance of thunderstorms developing in northeast KS/southeast Nebraska in the next couple hours. These thunderstorms could move across TOP and FOE in the 02Z to 07Z time frame, but confidence is not high. MHK has a lesser chance and have left any indicator out at this time. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...67 LONG TERM...Bowen AVIATION...GDP
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1144 PM MDT THU JUL 3 2014 .UPDATE... ISSUED AT 844 PM MDT THU JUL 3 2014 SMALL CLUSTER OF THUNDERSTORMS HANGING TOUGH NEAR THE WESTERN END OF THE FORECAST AREA. NOTHING REALLY CATCHING THIS...AND THIS CLUSTER IS MOSTLY BEING DRIVEN BY MESOSCALE AFFECTS. SO RAISED POPS SIGNIFICANTLY IN THE FAR WEST THROUGH THE EVENING. LEFT THE POPS ALONE AFTER MIDNIGHT WITH ELEVATED CONVECTION STILL POSSIBLE IN THE FAR EAST LATE TONIGHT INTO EARLY TOMORROW MORNING. BASED ON THUNDERSTORM BLOWOFF TO THE WEST AND WHAT IS LOOKING LIKE SOME STRATUS ADVECTION LATER TONIGHT...INCREASED CLOUD COVER. NOT SURE HOW FAR EAST CONVECTION WILL BE TOMORROW AFTERNOON AND WAS TEMPTED TO PULL IT BACK FURTHER WEST. HOWEVER...THE HRRR FOR MOST OF THIS SHIFT AND NOW THE RAP ARE HINTING AT A CLUSTER OF THUNDERSTORMS MOVING JUST NORTH OF OUR AREA LATER TONIGHT AND THROWING OUT A RATHER SIGNIFICANT OUTFLOW BOUNDARY THAT GETS DRAPED OVER OUR AREA TOMORROW. THIS COULD HAVE A MAJOR IMPACT ON THE FORECAST...ESPECIALLY WITH THE CONVECTION. SO CHOSE TO NOT DO ANYTHING WITH THE POPS DUE TO POSSIBLE MESOSCALE INFLUENCES AND WILL LET THE OVERNIGHT SHIFT WATCH THIS. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 220 PM MDT THU JUL 3 2014 LATEST VISIBLE SATELLITE INDICATES CUMULUS CLOUDS DEVELOPING GENERALLY EAST OF THE COLORADO BORDER AHEAD OF A 700MB SHORT WAVE TROUGH WHERE DEW POINTS ARE ABOVE 60 DEGREES. AT THE SURFACE BREEZY SOUTH WINDS HAVE BEEN REPORTED ALONG AND EAST OF THE COLORADO BORDER...WITH GUSTS NEAR 35 MPH. FURTHER WEST A DRY LINE WAS LOCATED WEST OF LIMON EXTENDING TO THE NORTH/SOUTH. AS THE AFTERNOON PROGRESSES THE DRY LINE WILL MOVE TO JUST WEST OF THE KIT CARSON AND CHEYENNE COUNTIES. MEANWHILE A WEAK 500MB TROUGH OVER THE DRY LINE MAY SPARK SOME ISOLATED CONVECTION THIS AFTERNOON. THIS EVENING THE 500MB TROUGH DEEPENS SOME AND MOVES EAST THROUGH THE NIGHT. WITH PARCELS ABLE TO TAP INTO THE SURFACE BASED CAPE INTO MID EVENING...DECIDED TO INCLUDE SLIGHT CHANCES FOR RAINFALL JUST AHEAD OF THE TROUGH. OVERNIGHT ELEVATED CAPE ABOVE 800MB DEVELOPS OVER THE EASTERN 1/3 OF THE AREA AS THE LOW LEVEL JET ADVECTS HIGHER MOISTURE NORTHWARD. INCLUDED SLIGHT CHANCES FOR RAINFALL OVERNIGHT OVER THE EAST 1/3 AS THE 500MB SHORT WAVE TROUGH MOVES OVER THE ELEVATED CAPE AND THE NOSE OF THE LOW LEVEL JET DEVELOPS NEAR SUNRISE. FRIDAY MORNING SOME ISOLATED CONVECTION MAY CONTINUE OVER THE EAST 1/3 AS ELEVATED CONVECTION LINGERS AHEAD OF THE 500MB SHORT WAVE TROUGH. DURING THE AFTERNOON THE DRY LINE WEST OF THE AREA MOVES EAST TO THE CO/KS LINE AS ANOTHER 500MB SHORT WAVE TROUGH DEVELOPS OVERHEAD. ISENTROPIC LIFT APPEARS TO BE STRONGER WITH THIS TROUGH THAN THE PREVIOUS ONE...AND WITH THE ADDED HELP OF THE DRY LINE HAVE A BIT HIGHER CHANCES FOR RAINFALL DURING THE AFTERNOON THAN FOR TODAY. THERE MAY BE SOME ISOLATED CONVECTION ACCOMPANYING THE DRY LINE INTO THE AREA FROM THE WEST BUT STORM COVERAGE SHOULD INCREASE DURING THE AFTERNOON AS THE 500MB TROUGH DEEPENS OVER THE DRY LINE AND MOVES EAST INTO BETTER INSTABILITY. AM NOT ANTICIPATING ANY SEVERE THUNDERSTORMS DURING THE AFTERNOON SINCE 0-6KM SHEAR WILL BE 20-25KTS...DECLINING THROUGH THE AFTERNOON AS STORM COVERAGE INCREASES. SOUTH WINDS WILL INCREASE DURING THE MID MORNING...WITH THE STRONGEST WINDS GENERALLY EAST OF HWY 25. TEMPERATURES WILL BE AROUND 10 DEGREES WARMER THAN TODAY AS A WARMER AIR MASS MOVES IN FROM THE WEST. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 220 PM MDT THU JUL 3 2014 THE UPPER RIDGE BREAKS DOWN SOME FRIDAY NIGHT AND THEN REBUILDS THROUGH SUNDAY. A SURFACE TROUGH WILL BE IN EASTERN COLORADO THROUGH SATURDAY NIGHT. SURFACE HIGH PRESSURE WILL MOVE INTO THE AREA SUNDAY. VERY WARM H7 TEMPERATURES FROM 14 TO 16 C ACROSS THE WESTERN HALF OF THE FA FRIDAY EVENING WILL MAKE IT DIFFICULT FOR STORMS TO DEVELOP. ANY STORMS THAT DO DEVELOP SHOULD FORM ON THE SURFACE TROUGH AND WILL MOVE VERY SLOWLY EAST WITH 0-6KM WINDS AT 5 TO 10KTS. ALTHOUGH THERE IS BETTER MOISTURE IN THE FAR SOUTHEAST FA, IT IS UNCERTAIN THAT STORMS WOULD MAKE IT THAT FAR. SLIGHT CHANCE POPS APPEAR TO BE HIGH ENOUGH FOR THIS SCENARIO. FOR SATURDAY THROUGH SUNDAY EVEN WARMER H7 TEMPERATURES SPREAD ACROSS THE FA.ALONG WITH SUBSIDENCE. POPS WILL BE NIL FOR THESE PERIODS. 850MB TEMPERATURES AT 32 WILL SUPPORT MAX TEMPERATURES NEAR 100 SATURDAY AND SUNDAY. MIN TEMPERATURES WILL BE IN THE MID TO UPPER 60S. IN THE EXTENDED...(SUNDAY NIGHT THROUGH THURSDAY)...NORTHWEST FLOW WILL PREVAIL ACROSS THE CENTRAL PLAINS THROUGH THIS PART OF THE FORECAST. NUMEROUS SHORTWAVES IN THE FLOW WILL BRING AT LEAST A SLIGHT CHANCE OR CHANCE OF THUNDERSTORMS TO THE FA. WITH THE EXCEPTION OF SUNDAY NIGHT, THUNDERSTORMS WILL BE POSSIBLE EACH DAY. MAX TEMPERATURES WILL REACH THE LOWER 90S. MIN TEMPERATURES WILL RANGE FROM THE MID 60S TO THE UPPER 60S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1140 PM MDT THU JUL 3 2014 AT KGLD...EXPECT MVFR CEILINGS TO DEVELOP BETWEEN 09Z AND 12Z AND CONTINUE THROUGH MID MORNING. OTHERWISE VFR CONDITIONS ARE EXPECTED AT BOTH SITES. WHAT ELEVATED CONVECTION OCCURS TONIGHT LOOKS TO REMAIN TO THE EAST OF BOTH SITES. SOME GUSTY WINDS EARLY IN THE PERIOD WILL DECREASE SHORTLY BUT WILL ONCE AGAIN BECOME GUSTY FROM THE SOUTH AFTER THE SUN COMES UP. SOUNDINGS FOR TOMORROW AFTERNOON AND EVENING WOULD INDICATE THAT NO THUNDERSTORMS WILL AFFECT EITHER SITE. SINCE TOO FAR OUT AND TOO MUCH UNCERTAINTY...CHOSE TO LEAVE ALL MENTION OF THUNDERSTORMS OUT OF BOTH TAFS. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...BULLER SHORT TERM...FS LONG TERM...JTL AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
713 PM EDT SAT JUL 5 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 424 PM EDT SAT JUL 5 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A RIDGE FROM THE SW CONUS INTO THE NRN PLAINS AND A DOWNSTREAM WNW FLOW THROUGH THE NRN GREAT LAKES. A WEAK SHORTWAVE TROUGH OVER NW ONTARIO(NW OF LAKE SUPERIOR) COMBINED WITH 25-30 KNOT 850-750 MB INFLOW OF MODERATELY UNSTABLE AIR (MUCAPE VALUES OF 1000-1500 J/KG) AND 40 KNOT 0-6KM SHEAR SUPPORTED STRONG CONVECTION OVER NE MN AND ADJOINING PORTION OF ONTARIO. SOME SHRA/TSRA WERE ALSO SLIDING INTO LAKE SUPERIOR BUT WERE WEAKENING AS THE CONVECTION MOVED AWAY FROM THE MORE UNSTABLE AIR. OTHERWISE...SUNSHINE AND SSW FLOW WAA PUSHED TEMPS INTO THE UPPER 70S AND LOWER 80S. TONIGHT...EXPECT THAT THE ONGOING SHRA/TSRA INTO WRN LAKE SUPERIOR WILL CONTINUE TO WEAKEN AS THEY SLIDE TO THE EAST THROUGH THE NRN HALF OF LAKE SUPERIOR...PER RADAR TRENDS AND SHORT RANG HIGH RES MODELS. ADDITIONAL CONVECTION IS LIKELY TO DEVELOP UPSTREAM LATE THIS EVENING AS ANOTHER WEAK SHRTWV OVER SRN MANITOBA MOVES TOWARD THE AREA. HOWEVER...UNCERTAINTY IS MUCH HIGHER WITH THE POSSIBILITY OF MCS DEVELOPMENT AND ITS EVENTUAL TRACK. EXPECT THAT THE HIGHER SHRA/TSRA WILL REMAIN TO THE NORTH AND WEST OF UPPER MI BUT THAT SOME MAY MOVE INTO UPPER MI...ESPECIALLY AFTER 06Z. WITH ONLY LIMITED MUCAPE INTO THE 500-1000 J/KG RANGE...ANY TSTORMS SHOULD REMAIN BELOW SEVERE LIMITS. SUNDAY...THE BEST CHANCE FOR SHRA/TSRA IS EXPECTED DURING THE AFTERNOON AS A STRONGER SHRTWV AND COLD FRONT MOVE TOWARD THE AREA. THERE WILL BE A CONDITIONAL RISK FOR STRONG/SEVERE STORMS THAT DEPENDS ON THE AMOUNT OF THICKER CLOUDS THAT LINGER INTO THE AFTERNOON. IF ENOUGH CLEARING DEVELOPS FOR A FEW HOURS TO ALLOW TEMPS TO REBOUND INTO THE LOWER 80S(DEWPOINTS IN THE MID TO UPPER 60S)...MLCAPE VALUES INTO THE 1K-2K RANGE COMBINED WITH 0-6KM SHEAR OF 35-40 KNOTS WILL SUPPORT STRONG/SEVERE ORGANIZED STORMS. 0-1KM HELICITY/SHAPE IS ALSO FAVORABLE FOR SOME ROTATING STORMS/SUPERCELLS. IF MORE PROMINENT CLOUDS REMAIN INTO THE AFTERNOON...THE GREATER INSTABILITY AND SEVERE POTENTIAL WOULD BE MAINLY OVER WI AND POSSIBLY INTO THE FAR SRN CWA. NMRS SHRA/TSRA OVER CNTRL UPPER MI DURING THE AFTERNOON WILL SHIFT TOWARD THE S AND ERN CWA BY LATE AFTERNOON AND EVENING. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 330 PM EDT SAT JUL 5 2014 A SHORTWAVE TROUGH ALOFT AND SFC LOW WILL BE JUST N OF THE CWA WITH A COLD FRONT ACROSS THE CENTRAL CWA AT 00Z MON. CONVECTION...POSSIBLY SEVERE /SEE SHORT TERM DISCUSSION FOR MORE DETAILS ON SEVERE THREAT/...WILL BE ONGOING ALONG AND AHEAD OF THE FRONT OVER MAINLY THE ERN HALF OF THE CWA. BY 06Z MON...THE FRONT WILL HAVE MOVED TO THE ERN CWA...WITH MOST OF THE CONVECTION E OF THE CWA. ADDITIONAL SHORTWAVE ENERGY LOOKS TO MOVE N OF THE CWA DURING THE DAY ON MON...BUT FORCING WILL STAY N KEEPING THE CWA DRY FOR THE MOST PART. THE NAM IS SHOWING A SHORTWAVE MOVING IN MON EVENING...WHICH WOULD RESULT IN PRECIP LATE IN THE DAY OVER THE WRN CWA...BUT MOST OTHER MODELS SHOW THIS COMING IN MON NIGHT OR EVEN EARLY TUE. AS IS USUAL WITH SUBTLE SHORTWAVES AND ASSOCIATED CONVECTIVE COMPLEXES...CONFIDENCE IN EXACT DETAILS IS QUITE LOW THIS FAR OUT. CONFIDENCE CONTINUES TO BE LOW THROUGH THE MIDDLE OF THE WEEK AS MODELS INDICATE ADDITIONAL SHORTWAVE ENERGY MON NIGHT OR TUE...WHICH APPEARS TO STAY S OF THE CWA. YET ANOTHER SHORTWAVE IS MODELED TO MOVE OVER THE NRN CWA TUE NIGHT...BUT WITH LESS MOISTURE TO WORK WITH...PRECIP SHOULD BE CONFINED TO NEAR THE SHORTWAVE. WITH THE GENERAL TROUGHING OVER THE REGION THROUGH MIDWEEK...EXPECT TEMPS TO BE A LITTLE BELOW NORMAL. HOWEVER...UPPER RIDGING BUILDING INTO THE REGION LATER IN THE WEEK AND POSSIBLY INTO NEXT WEEKEND WILL LEAD TO AN ABOVE NORMAL TREND FOR TEMPERATURES. CONFIDENCE IS LOW THAT ANY SIGNIFICANT PRECIP WILL OCCUR THU THROUGH NEXT SAT...BUT THE BEST CHANCES FOR PRECIP WILL BE ON SAT. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 712 PM EDT SAT JUL 5 2014 VFR CONDITIONS THIS EVENING ARE EXPECTED TO GIVE WAY TO SOME MVFR CIGS/VSBY LATE TONIGHT AS LOW LEVEL MOISTURE CONTINUES TO MOVE TOWARD THE AREA WITH THE INCREASING SRLY FLOW. SOME TSRA ARE ALSO EXPECTED TO DEVELOP AND MOVE INTO THE CWA TONIGHT. HOWEVER...SINCE CONFIDENCE IN THE POSITION/TIMING IS ONLY MARGINAL...TEMPO GROUPS WERE INCLUDED OVER THE WEST AND NORTH. WITH DAYTIME HEATING...CONDITIONS SHOULD IMPROVE TO VFR BY LATE SUN MORNING AND HAVE ANOTHER CHANCE OF PCPN FOR LATE SUN MORNING INTO SUNDAY AFTERNOON AT ALL SITES. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 424 PM EDT SAT JUL 5 2014 HIGH PRESSURE ACROSS THE OHIO VALLEY WILL CONTINUE TO SLOWLY EXIT EASTWARD THROUGH SUNDAY. LOOK FOR THE RIDGE ACROSS UPPER MICHIGAN TO WEAKEN AS LOW PRESSURE NEAR S MANITOBA SUNDAY MORNING SLIDES ACROSS ONTARIO AND LAKE SUPERIOR SUNDAY AFTERNOON AND EVENING. THIS LOW WILL DEEPEN SW OF JAMES BAY LATE SUNDAY NIGHT AND MONDAY MORNING...WHILE DRAGGING A TROUGH AVERAGING ACROSS LAKE SUPERIOR. A WEAK TROUGH WILL REMAIN DRAPED ACROSS NORTHERN AND SOUTHEAST ONTARIO THROUGH WEDNESDAY A RIDGE BUILDS OVER THE NORTHERN HIGH PLAINS. WINDS SHOULD REMAIN AT OR BELOW 20 KNOTS...EXCEPT IN OR NEAR ANY STRONGER THUNDERSTORMS. FOG...POSSIBLY DENSE...WILL BE POSSIBLE FROM LATE TONIGHT THROUGH EARLY MONDAY MORNING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...07 MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
137 PM EDT FRI JUL 4 2014 .UPDATE... ISSUED AT 1153 AM EDT FRI JUL 4 2014 LOOKS LIKE A GREAT /AND DRY/ DAY FOR OUTDOOR CELEBRATIONS ACROSS UPPER MI. HAVE PULLED SPRINKLES FROM THE FORECAST WHERE THEY WERE MENTIONED OVER NCENTRAL UPPER MI LATE THIS AFTERNOON/EVENING. LOW LEVELS ARE QUITE DRY AND ANY SHOWER ACTIVITY SHOULD NOT BE ABLE TO OVERCOME THE DRYNESS. ADDITIONALLY...NONE OF THE MODELS ARE SHOWING QPF IN THE AFOREMENTIONED AREA. THE RAP EVEN CORRECTLY SHOWS THE WEAK SHOWER OR TWO CURRENTLY N OF THE MN ARROWHEAD...WHICH WERE NOT PRESENT AT MODEL INITIALIZATION...ASSOCIATED WITH A WEAK SHORTWAVE MOVING TOWARD THE AREA...BUT DISSIPATES THOSE SHOWERS AS THEY MOVE CLOSER TO THE SFC RIDGE OVER THE CWA. VIRGA SEEMS A MORE LIKELY OUTCOME THAN SPRINKLES THIS AFTERNOON/EVENING. AS FOR PRECIP CHANCES OVER FAR WRN UPPER MI /AFTER 03Z SAT/...THE UPSTREAM SHOWER/THUNDERSTORM ACTIVITY OVER WCENTRAL MN HAS NOT PANNED OUT QUITE AS STRONG AS PREVIOUS HIGH-RES MODEL RUNS INDICATED. THE LATEST FEW RUNS OF THE RAP SHOW A FEW ISOLATED SHOWERS PRODUCING 0.01-0.03 INCHES OF QPF FROM GOGEBIC COUNTY MI TO ASHLAND COUNTY WI. THE LATEST LOCAL HIGH-RES WRF RUN KEEPS THIS AREA DRY. HAVE CONTINUED A DRY FORECAST THROUGH 03Z SAT FOR FAR WRN UPPER MI. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 348 AM EDT FRI JUL 4 2014 THE UPPER TROUGH AXIS IS STILL OFF TO THE EAST OF THE AREA EARLY THIS MORNING...WHICH CONTINUES TO ALLOW FOR WEAK SHORTWAVES TO DROP SOUTHEAST THROUGH THE REGION. THERE ARE TWO LARGER WAVES TO NOTE AND A MORE SUBTLE THIRD WAVE THAT COULD AFFECT THE AREA THIS AFTERNOON. THE FIRST WAVE DROPPED THROUGH THE CWA SHORTLY AFTER MIDNIGHT AND PRODUCED SCATTERED/FEW MID CLOUDS OVER LAKE SUPERIOR AND THE NORTHEASTERN HALF OF UPPER MICHIGAN. THIS WAVE WILL CONTINUE TO THE SOUTHEAST EARLY THIS MORNING AND WILL ONLY BRING A FEW MID CLOUDS TO THE EASTERN THIRD OF THE U.P. OTHERWISE...THE REST OF THE CWA IS EXPERIENCING CLEAR SKIES AND LIGHT WINDS UNDER THE NORTHWESTERN EDGE OF A HIGH PRESSURE RIDGE STRETCHING NORTH FROM A HIGH CENTERED IN SOUTHERN WISCONSIN. THOSE CONDITIONS HAVE PRODUCED GOOD RADIATIONAL COOLING AND HAS ALLOWED 3AM TEMPERATURES TO FALL INTO THE 40S...WITH THE LOWEST VALUES AT THE NORMAL COLD SPOTS (DOE LAKE...SPINCICH LATE) IN THE UPPER 30S. THE NEXT SHORTWAVE...WHICH LOOKS MORE POTENT THE CURRENT WAVE ON WV IMAGERY AND WITH THE AMOUNT OF MID CLOUDS ASSOCIATED WITH IT...IS DROPPING SOUTHEAST THROUGH NORTHERN ONTARIO AND JUST STARTING TO COME INTO NORTHERN LAKE SUPERIOR. MODELS ARE INSISTENT ON THIS WAVE QUICKLY DROPPING SOUTHEAST THROUGH EASTERN LAKE SUPERIOR AND EASTERN UPPER MICHIGAN OVER THE NEXT FEW HOURS AND GENERALLY SOUTHEAST OF THE AREA BY 15Z. THOSE TWO WAVES WILL HELP KICK THE UPPER TROUGH EAST AND OUT OF THE GREAT LAKES REGION TODAY...AS IT MERGES WITH HURRICANE ARTHUR TONIGHT. BACK TO THIS AREA...THE HIGH PRESSURE CENTERED IN NORTHERN ILLINOIS WILL SHIFT EAST TODAY...BUT STILL KEEP THE SURFACE RIDGE OVER THE AREA. THESE LIGHT WINDS AND GENERALLY SUNNY CONDITIONS TO START THE DAY WILL LEAD TO A QUICK WARM-UP AND THE DEVELOPMENT OF LAKE BREEZES NEAR THE GREAT LAKES. LIKE YESTERDAY...THE DEEP MIXING INLAND WILL LIKELY LEAD TO CU DEVELOPMENT AROUND 6-8KFT SO HAVE FOLLOWED 750MB MOISTURE FROM THE MODELS FOR SKY COVER TODAY. THEREFORE...HAVE CU DEVELOPING LATE IN THE DAY (GENERALLY 19-20Z AND LATER) AND HAVE THE INTERIOR WEST AND ESPECIALLY NORTH CENTRAL BECOMING PARTLY TO NEARLY MOSTLY CLOUDY FOR THE LATE AFTERNOON. MODEL MOISTURE ON THAT LEVEL IS GENERALLY A LITTLE DRIER THAN YESTERDAY...WHICH SEEMS TO BE WHY MOST OF THE MODELS ARE INDICATING NO PRECIP. THE ONLY MODEL PRODUCING PRECIP IS THE 00Z NAM...AND EVEN THAT HAS TRIMMED BACK THE QPF FROM WHAT THE 07/03 12Z/18Z RUNS WERE SHOWING (NOW JUST SHOWING A LITTLE SPECK OF 0.01IN QPF OVER MARQUETTE COUNTY). THE AREA THAT IS SHOWS PRECIP MATCHES UP WITH WHERE THE LAKE SUPERIOR/MICHIGAN BREEZE CONVERGENCE SHOULD BE LATE THIS AFTERNOON...BUT IT IS LIKELY MORE DUE TO REMAINING IN AN AREA THAT ISN/T EXPERIENCING THE LAKE STABILITY. A FEW OF THE HIRES MODELS THAT DON/T SPIT OUT QPF DO INDICATE SOME LIGHT RETURNS ON THE MODEL SIMULATED COMP REFLECTIVITY. THINK THAT THE DRY LOW LEVEL AIR IS CONTRIBUTING TO THIS (INVERTED-V LOOK TO THE SOUNDINGS) AND LIMITING PRECIP ACCUMULATION. IT DOES APPEAR THAT A REALLY THIN SHORTWAVE WILL SLIDE ACROSS THE AREA THIS AFTERNOON (CURRENTLY PRODUCING THE HIGH CLOUDS NEAR AND EAST OF LAKE WINNIPEG)...WHICH COULD AID IN THE CLOUD DEVELOPMENT. SINCE THE HIGH RESOLUTION MODELS PERFORMED VERY WELL YESTERDAY...WOULD HAVE TO BELIEVE THAT THEIR IDEA OF NO PRECIP TODAY IS REASONABLE. THUS...WILL TRIM BACK THE SLIGHT CHANCES TO JUST SOME SPRINKLES FOR GENERALLY THE MARQUETTE COUNTY AREA. SINCE THE HIGH PRESSURE CENTER CONTINUES TO THE EAST TONIGHT...THE INFLUENCE OF THE HIGH PRESSURE RIDGE WILL WEAKEN OVER THE AREA. IN ADDITION...A LOW THAT DEVELOPS IN SASKATCHEWAN TODAY WILL BEGIN TO MOVE EAST AND LEAD TO INCREASING SOUTHERLY FLOW OVER THE AREA AND THE UPPER MISSISSIPPI VALLEY. EXPECT SHOWERS AND THUNDERSTORMS TO DEVELOP OVER NORTH DAKOTA AND NORTHERN MINNESOTA THIS AFTERNOON UNDER THE WARM AIR ADVECTION REGIME AHEAD OF THE SURFACE TROUGH STRETCHING SOUTH JUST TO THE EAST OF THE ROCKIES. THINK THESE SHOWERS AND THUNDERSTORMS WILL SHIFT TO THE EAST TONIGHT WITH HELP FROM A SHORTWAVE ROUNDING THE WEAK UPPER RIDGE OVER THE WESTERN CONUS AND MOVE THE SHOWERS AND THUNDERSTORMS TOWARDS THE AREA TONIGHT. STORM MOTIONS ARE GENERALLY IN A EASTERLY DIRECTION AND SIMILAR TO THE EAST-NORTHEAST TRACK OF THE WAA...SO THINK THAT THE MODEL QPF FIELDS ARE DOING A DECENT JOB IN TRACKING IT TO THE EAST-NORTHEAST ALONG THE US/CANADIAN BORDER. THEREFORE...WILL CONTINUE TO SHOW A GRADUALLY INCREASING SLIGHT/CHANCE POPS OVER THE NORTHWEST THIRD OF THE CWA DURING THE OVERNIGHT HOURS TONIGHT. OTHERWISE...LOOKS TO BE A REALLY NICE EVENING FOR FIREWORKS WITH TEMPERATURES AT SUNSET IN THE 60S. ONE LAST ITEM TO NOTE. WILL NEED TO WATCH THE AREA IN EASTERN SD AND SOUTHWESTERN MINNESOTA. NCEP WRF RUNS THE AREA WHERE THERE ARE SOME BROKEN/OVERCAST CLOUDS AND ISOLATE SHOWERS EXPANDING THIS MORNING AND THEN LIFTING TOWARDS THE FAR WESTERN CWA TOWARDS SUNSET. WILL NEED TO MONITOR THOSE TRENDS THIS MORNING. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 547 AM EDT FRI JUL 4 2014 A SHORTWAVE RIPPLING THROUGH A WNW FLOW ALOFT WILL PUSH SFC HIGH PRESSURE TO THE EAST BY SATURDAY ALLOWING FOR A WARMING TREND THIS WEEKEND AS HIGHS BRIEFLY GO BACK ABOVE NORMAL. INCREASING MOISTURE/INSTABILITY AHEAD OF AN APPROACHING COLD FRONT WILL ALSO BRING INCREASED CHANCES OF SHRA/TSRA SATURDAY NIGHT INTO SUNDAY. IN THE WAKE OF THE COLD FROPA ON SUNDAY...WE WILL SEE A RETURN TO TROUGHING ALOFT AND A COOLER AIRMASS FOR EARLY-MID NEXT WEEK OVER THE WESTERN GREAT LAKES AS RIDGING BEGINS TO BUILD OVER THE WESTERN CONUS. MODELS DO HINT THAT BY THE FOLLOWING WEEKEND...MID JULY...RIDGING ALOFT AND A PERIOD OF WARMER TEMPERATURES MAY SPREAD FROM THE PLAINS ACROSS THE WESTERN GREAT LAKES. AGAIN THIS WARMUP DOES NOT LOOK TO PERSIST FOR MORE THAN A COUPLE OF DAYS. SATURDAY...ATTENTION IS FOCUSED ON SHORTWAVE APPROACHING FROM SOUTHERN MANITOBA/NORTHWEST ONTARIO. MODELS SHOW CONVECTION FIRING AHEAD OF THIS SHORTWAVE FRI EVENING OVER THE NRN PLAINS INTO NW ONTARIO ALONG 1000-850 MB THETA-E AXIS...AREA OF 1000+ J/KG ELEVATED MUCAPE AND AT NOSE OF 35 KT 8H JET MAX. MODELS SHOW THE POSSIBILITY THAT THE REMNANTS OF THESE STORMS COULD REACH INTO WRN/NCNTRL LAKE SUPERIOR AND NW UPPER MI LATE FRIDAY NIGHT INTO SATURDAY MORNING AND WILL MAINTAIN SOME LOW CHC POPS TO ACCOUNT FOR THIS POSSIBILITY. FOR THE MOST PART HOWEVER...EXPECT STORMS TO WEAKEN AS THEY MOVE INTO DRIER AND MORE STABLE AIR OVER LAKE SUPERIOR. WILL MAINTAIN A DIMINISHING TREND TO POPS THROUGH THE DAY ON SATURDAY AS SHORTWAVE EVENTUALLY MOVES NORTHEAST OF THE REGION AND TAKES BEST H85-H7 MOISTURE TRANSPORT WITH IT. UNDER PARTIAL SUNSHINE AND GUSTY SW WINDS TO 20-25 KTS...EXPECT TEMPS TO PUSH INTO THE LOWER 80S AWAY FM LK MICHIGAN WHERE IT SHOULD STAY IN THE UPPER 60S TO LOWER 70S. HUMIDITY WILL ALSO BE ON THE INCREASE. SATURDAY NIGHT...INCREASING WAA ESPECIALLY FROM THE WEST AFTER MIDNIGHT AHEAD OF ADVANCING SHORTWAVE FROM SCSNTRL CANADA WILL LEAD TO INCREASING CHCS OF SHRA/TSRA AS COLD FRONT/INSTABILITY AXIS WORKS EAST TOWARD UPPER GREAT LAKES. BASED ON WHERE BEST INSTABILITY IS LOCATED NEAR THE APPROACHING FRONTAL BOUNDARY IT LOOKS LIKE STORMS WOULD INITIATE OVER NRN MN OR NEAR THE CANADIAN BORDER. FORWARD PROPAGATING CORFIDI VECTORS AND DIFFLUENT THICKNESS PATTERN WOULD SUGGEST STORMS SOME STORMS COULD MOVE INTO WRN UPPER MI LATE SAT NIGHT SO WILL KEEP HIGHER CHC POPS OVER THESE AREAS WITH SLIGHT CHC POPS TO THE SE AND ERN CWA. GIVEN MARGINAL INSTABILITY PRESENT NOT EXPECTING ANY SEVERE STORMS. SUNDAY...BEST CHANCE OF SHRA/TSRA...POTENTIALLY STRONG OR SEVERE WILL BE SUNDAY AFTERNOON INTO SUNDAY EVENING AS WNW FLOW ALOFT CONTINUES TO SEND SHORTWAVES OVER THE AREA...AND SFC COLD FRONT SAGS SE ACROSS UPPER MI. KEY WILL BE HOW MUCH INSOLATION/HEATING AND SFC BASED INSTABILITY CAN BE REALIZED. MAIN NEGATIVE FACTOR IS H85 WINDS VEERING MORE WNW BEFORE ARRIVAL OF THE FRONT...CUTTING DOWN ON LOW-LEVEL THETA-E ADVECTION. BEST SHOT OF STRONGER STORMS WOULD PROBABLY BE OVER SOUTH CENTRAL AND SOUTHEAST CWA WHERE BETTER INSTABILITY AXIS OF NEAR 1000 J/KG OF MLCAPE WILL BE LOCATED. MAX TEMPS SHOULD BE WELL ABOVE NORMAL BASED ON MIXING DOWN H85 TEMPS UP TO +18C...EXPECT HIGHS WELL INTO THE 80S. IF THERE IS ENOUGH SUNSHINE...MAY SEE TEMPS NEAR 90 DEGREES. BEST SHOT OF SUCH WARM TEMPS WOULD PROBABLY BE SCNTRL CWA AWAY FM LK MICHIGAN. BEHIND SUNDAY/S COLD FROPA....TROUGHING ALOFT BECOMES RE-ESTABLISHED EARLY NEXT WEEK. NW FLOW ALOFT AND PERIODIC SHORTWAVES DROPPING THROUGH THE FLOW PATTERN COULD TRIGGER SCT SHRA AND MAYBE EVEN AN ISOLD TSRA AT TIMES MON INTO WED...ESPECIALLY INLAND WEST HALF. OTHERWISE...NORTH TO NORTH WINDS AT THE SFC WILL KEEP STABLIZED LAKE FLOW OVER MUCH OF THE CWA. TEMPS WILL BE BELOW NORMAL...WITH UPR 50S TO UPR 60S NEAR LK SUPERIOR AND READINGS IN THE 70S INLAND AND NEAR LK MICHIGAN. MODELS HINT AT RIDGING AND DRIER CONDITIONS MOVING IN FROM THE WEST BY THU WITH TEMPS LIKELY REBOUNDING CLOSER TO NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 135 PM EDT FRI JUL 4 2014 A HIGH PRESSURE RIDGE OVER THE AREA WILL LEAD TO VFR CONDITIONS THROUGH THE TAF PERIOD. LIGHT WINDS ASSOCIATED WITH THIS RIDGE WILL ALLOW LAKE BREEZES TO DEVELOP AND POTENTIALLY AFFECT ALL THREE SITES TODAY. KIWD MAY SWITCH AROUND FOR A COUPLE HOURS EARLY THIS AFTERNOON...BUT THEN SWITCH BACK TO THE SOUTHWEST. KCMX WILL SHIFT TO THE EAST LATE IN THE DAY...WHILE KSAW WILL SHIFT TO THE NORTHEAST IN THE NEXT HOUR OR SO FROM THE LAKE SUPERIOR BREEZE AND THEN SWITCH TO THE SOUTHEAST LATE IN THE AFTERNOON AS THE LAKE MICHIGAN BREEZE MOVES THROUGH. THE BEST OPPORTUNITY FOR SHOWERS AND THUNDERSTORMS WILL COME AFTER MIDNIGHT TONIGHT FOR KCMX...ALTHOUGH MOST OF THEM SHOULD STAY TO THE NORTHWEST OF THE SITE. FINALLY...MAY NEED LLWS AT KIWD OVERNIGHT TONIGHT...AS THE LOW LEVEL JET STRENGTHENS AHEAD OF THE LOW PRESSURE SYSTEM IN CENTRAL CANADA. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 348 AM EDT FRI JUL 4 2014 A HIGH PRESSURE RIDGE OVER THE UPPER GREAT LAKES REGION WILL LEAD TO LIGHT WINDS TODAY AND INTO THIS EVENING. AS THE RIDGE SLIDES SOUTHEAST TONIGHT...WINDS WILL BE ON THE INCREASE OUT OF THE SOUTH AFTER MIDNIGHT TONIGHT AS A LOW PRESSURE SYSTEM MOVES EAST OUT OF CENTRAL CANADA. THIS LOW WILL STAY TO THE NORTH OF THE AREA THROUGH MONDAY AS IT MOVES INTO QUEBEC...BUT IT WILL DRAG A TROUGH ACROSS LAKE SUPERIOR SUNDAY NIGHT. EXPECT THE COOL LAKE SUPERIOR WATER TEMPERATURES TO HELP DEVELOP A MARINE LAYER THAT SHOULD KEEP WINDS BELOW 20KTS THROUGH SUNDAY. BEHIND THE TROUGH...WINDS WILL SHIFT TO THE NORTHWEST...BUT SHOULD REMAIN BELOW 20KTS AS A WEAK HIGH PRESSURE RIDGE QUICKLY MOVES INTO THE AREA BY MONDAY AFTERNOON. THE COMBINATION OF WARM MOIST AIR MOVING OVER LAKE SUPERIOR SATURDAY NIGHT INTO SUNDAY AND EXPECTED RAINFALL...WILL LEAD TO PATCHY TO AREAS OF FOG DEVELOPING OVER MAINLY THE NORTHERN HALF OF LAKE SUPERIOR SATURDAY NIGHT THROUGH SUNDAY NIGHT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ UPDATE...TITUS SHORT TERM...SRF LONG TERM...VOSS AVIATION...TITUS MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1153 AM EDT FRI JUL 4 2014 .UPDATE... ISSUED AT 1153 AM EDT FRI JUL 4 2014 LOOKS LIKE A GREAT /AND DRY/ DAY FOR OUTDOOR CELEBRATIONS ACROSS UPPER MI. HAVE PULLED SPRINKLES FROM THE FORECAST WHERE THEY WERE MENTIONED OVER NCENTRAL UPPER MI LATE THIS AFTERNOON/EVENING. LOW LEVELS ARE QUITE DRY AND ANY SHOWER ACTIVITY SHOULD NOT BE ABLE TO OVERCOME THE DRYNESS. ADDITIONALLY...NONE OF THE MODELS ARE SHOWING QPF IN THE AFOREMENTIONED AREA. THE RAP EVEN CORRECTLY SHOWS THE WEAK SHOWER OR TWO CURRENTLY N OF THE MN ARROWHEAD...WHICH WERE NOT PRESENT AT MODEL INITIALIZATION...ASSOCIATED WITH A WEAK SHORTWAVE MOVING TOWARD THE AREA...BUT DISSIPATES THOSE SHOWERS AS THEY MOVE CLOSER TO THE SFC RIDGE OVER THE CWA. VIRGA SEEMS A MORE LIKELY OUTCOME THAN SPRINKLES THIS AFTERNOON/EVENING. AS FOR PRECIP CHANCES OVER FAR WRN UPPER MI /AFTER 03Z SAT/...THE UPSTREAM SHOWER/THUNDERSTORM ACTIVITY OVER WCENTRAL MN HAS NOT PANNED OUT QUITE AS STRONG AS PREVIOUS HIGH-RES MODEL RUNS INDICATED. THE LATEST FEW RUNS OF THE RAP SHOW A FEW ISOLATED SHOWERS PRODUCING 0.01-0.03 INCHES OF QPF FROM GOGEBIC COUNTY MI TO ASHLAND COUNTY WI. THE LATEST LOCAL HIGH-RES WRF RUN KEEPS THIS AREA DRY. HAVE CONTINUED A DRY FORECAST THROUGH 03Z SAT FOR FAR WRN UPPER MI. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 348 AM EDT FRI JUL 4 2014 THE UPPER TROUGH AXIS IS STILL OFF TO THE EAST OF THE AREA EARLY THIS MORNING...WHICH CONTINUES TO ALLOW FOR WEAK SHORTWAVES TO DROP SOUTHEAST THROUGH THE REGION. THERE ARE TWO LARGER WAVES TO NOTE AND A MORE SUBTLE THIRD WAVE THAT COULD AFFECT THE AREA THIS AFTERNOON. THE FIRST WAVE DROPPED THROUGH THE CWA SHORTLY AFTER MIDNIGHT AND PRODUCED SCATTERED/FEW MID CLOUDS OVER LAKE SUPERIOR AND THE NORTHEASTERN HALF OF UPPER MICHIGAN. THIS WAVE WILL CONTINUE TO THE SOUTHEAST EARLY THIS MORNING AND WILL ONLY BRING A FEW MID CLOUDS TO THE EASTERN THIRD OF THE U.P. OTHERWISE...THE REST OF THE CWA IS EXPERIENCING CLEAR SKIES AND LIGHT WINDS UNDER THE NORTHWESTERN EDGE OF A HIGH PRESSURE RIDGE STRETCHING NORTH FROM A HIGH CENTERED IN SOUTHERN WISCONSIN. THOSE CONDITIONS HAVE PRODUCED GOOD RADIATIONAL COOLING AND HAS ALLOWED 3AM TEMPERATURES TO FALL INTO THE 40S...WITH THE LOWEST VALUES AT THE NORMAL COLD SPOTS (DOE LAKE...SPINCICH LATE) IN THE UPPER 30S. THE NEXT SHORTWAVE...WHICH LOOKS MORE POTENT THE CURRENT WAVE ON WV IMAGERY AND WITH THE AMOUNT OF MID CLOUDS ASSOCIATED WITH IT...IS DROPPING SOUTHEAST THROUGH NORTHERN ONTARIO AND JUST STARTING TO COME INTO NORTHERN LAKE SUPERIOR. MODELS ARE INSISTENT ON THIS WAVE QUICKLY DROPPING SOUTHEAST THROUGH EASTERN LAKE SUPERIOR AND EASTERN UPPER MICHIGAN OVER THE NEXT FEW HOURS AND GENERALLY SOUTHEAST OF THE AREA BY 15Z. THOSE TWO WAVES WILL HELP KICK THE UPPER TROUGH EAST AND OUT OF THE GREAT LAKES REGION TODAY...AS IT MERGES WITH HURRICANE ARTHUR TONIGHT. BACK TO THIS AREA...THE HIGH PRESSURE CENTERED IN NORTHERN ILLINOIS WILL SHIFT EAST TODAY...BUT STILL KEEP THE SURFACE RIDGE OVER THE AREA. THESE LIGHT WINDS AND GENERALLY SUNNY CONDITIONS TO START THE DAY WILL LEAD TO A QUICK WARM-UP AND THE DEVELOPMENT OF LAKE BREEZES NEAR THE GREAT LAKES. LIKE YESTERDAY...THE DEEP MIXING INLAND WILL LIKELY LEAD TO CU DEVELOPMENT AROUND 6-8KFT SO HAVE FOLLOWED 750MB MOISTURE FROM THE MODELS FOR SKY COVER TODAY. THEREFORE...HAVE CU DEVELOPING LATE IN THE DAY (GENERALLY 19-20Z AND LATER) AND HAVE THE INTERIOR WEST AND ESPECIALLY NORTH CENTRAL BECOMING PARTLY TO NEARLY MOSTLY CLOUDY FOR THE LATE AFTERNOON. MODEL MOISTURE ON THAT LEVEL IS GENERALLY A LITTLE DRIER THAN YESTERDAY...WHICH SEEMS TO BE WHY MOST OF THE MODELS ARE INDICATING NO PRECIP. THE ONLY MODEL PRODUCING PRECIP IS THE 00Z NAM...AND EVEN THAT HAS TRIMMED BACK THE QPF FROM WHAT THE 07/03 12Z/18Z RUNS WERE SHOWING (NOW JUST SHOWING A LITTLE SPECK OF 0.01IN QPF OVER MARQUETTE COUNTY). THE AREA THAT IS SHOWS PRECIP MATCHES UP WITH WHERE THE LAKE SUPERIOR/MICHIGAN BREEZE CONVERGENCE SHOULD BE LATE THIS AFTERNOON...BUT IT IS LIKELY MORE DUE TO REMAINING IN AN AREA THAT ISN/T EXPERIENCING THE LAKE STABILITY. A FEW OF THE HIRES MODELS THAT DON/T SPIT OUT QPF DO INDICATE SOME LIGHT RETURNS ON THE MODEL SIMULATED COMP REFLECTIVITY. THINK THAT THE DRY LOW LEVEL AIR IS CONTRIBUTING TO THIS (INVERTED-V LOOK TO THE SOUNDINGS) AND LIMITING PRECIP ACCUMULATION. IT DOES APPEAR THAT A REALLY THIN SHORTWAVE WILL SLIDE ACROSS THE AREA THIS AFTERNOON (CURRENTLY PRODUCING THE HIGH CLOUDS NEAR AND EAST OF LAKE WINNIPEG)...WHICH COULD AID IN THE CLOUD DEVELOPMENT. SINCE THE HIGH RESOLUTION MODELS PERFORMED VERY WELL YESTERDAY...WOULD HAVE TO BELIEVE THAT THEIR IDEA OF NO PRECIP TODAY IS REASONABLE. THUS...WILL TRIM BACK THE SLIGHT CHANCES TO JUST SOME SPRINKLES FOR GENERALLY THE MARQUETTE COUNTY AREA. SINCE THE HIGH PRESSURE CENTER CONTINUES TO THE EAST TONIGHT...THE INFLUENCE OF THE HIGH PRESSURE RIDGE WILL WEAKEN OVER THE AREA. IN ADDITION...A LOW THAT DEVELOPS IN SASKATCHEWAN TODAY WILL BEGIN TO MOVE EAST AND LEAD TO INCREASING SOUTHERLY FLOW OVER THE AREA AND THE UPPER MISSISSIPPI VALLEY. EXPECT SHOWERS AND THUNDERSTORMS TO DEVELOP OVER NORTH DAKOTA AND NORTHERN MINNESOTA THIS AFTERNOON UNDER THE WARM AIR ADVECTION REGIME AHEAD OF THE SURFACE TROUGH STRETCHING SOUTH JUST TO THE EAST OF THE ROCKIES. THINK THESE SHOWERS AND THUNDERSTORMS WILL SHIFT TO THE EAST TONIGHT WITH HELP FROM A SHORTWAVE ROUNDING THE WEAK UPPER RIDGE OVER THE WESTERN CONUS AND MOVE THE SHOWERS AND THUNDERSTORMS TOWARDS THE AREA TONIGHT. STORM MOTIONS ARE GENERALLY IN A EASTERLY DIRECTION AND SIMILAR TO THE EAST-NORTHEAST TRACK OF THE WAA...SO THINK THAT THE MODEL QPF FIELDS ARE DOING A DECENT JOB IN TRACKING IT TO THE EAST-NORTHEAST ALONG THE US/CANADIAN BORDER. THEREFORE...WILL CONTINUE TO SHOW A GRADUALLY INCREASING SLIGHT/CHANCE POPS OVER THE NORTHWEST THIRD OF THE CWA DURING THE OVERNIGHT HOURS TONIGHT. OTHERWISE...LOOKS TO BE A REALLY NICE EVENING FOR FIREWORKS WITH TEMPERATURES AT SUNSET IN THE 60S. ONE LAST ITEM TO NOTE. WILL NEED TO WATCH THE AREA IN EASTERN SD AND SOUTHWESTERN MINNESOTA. NCEP WRF RUNS THE AREA WHERE THERE ARE SOME BROKEN/OVERCAST CLOUDS AND ISOLATE SHOWERS EXPANDING THIS MORNING AND THEN LIFTING TOWARDS THE FAR WESTERN CWA TOWARDS SUNSET. WILL NEED TO MONITOR THOSE TRENDS THIS MORNING. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 547 AM EDT FRI JUL 4 2014 A SHORTWAVE RIPPLING THROUGH A WNW FLOW ALOFT WILL PUSH SFC HIGH PRESSURE TO THE EAST BY SATURDAY ALLOWING FOR A WARMING TREND THIS WEEKEND AS HIGHS BRIEFLY GO BACK ABOVE NORMAL. INCREASING MOISTURE/INSTABILITY AHEAD OF AN APPROACHING COLD FRONT WILL ALSO BRING INCREASED CHANCES OF SHRA/TSRA SATURDAY NIGHT INTO SUNDAY. IN THE WAKE OF THE COLD FROPA ON SUNDAY...WE WILL SEE A RETURN TO TROUGHING ALOFT AND A COOLER AIRMASS FOR EARLY-MID NEXT WEEK OVER THE WESTERN GREAT LAKES AS RIDGING BEGINS TO BUILD OVER THE WESTERN CONUS. MODELS DO HINT THAT BY THE FOLLOWING WEEKEND...MID JULY...RIDGING ALOFT AND A PERIOD OF WARMER TEMPERATURES MAY SPREAD FROM THE PLAINS ACROSS THE WESTERN GREAT LAKES. AGAIN THIS WARMUP DOES NOT LOOK TO PERSIST FOR MORE THAN A COUPLE OF DAYS. SATURDAY...ATTENTION IS FOCUSED ON SHORTWAVE APPROACHING FROM SOUTHERN MANITOBA/NORTHWEST ONTARIO. MODELS SHOW CONVECTION FIRING AHEAD OF THIS SHORTWAVE FRI EVENING OVER THE NRN PLAINS INTO NW ONTARIO ALONG 1000-850 MB THETA-E AXIS...AREA OF 1000+ J/KG ELEVATED MUCAPE AND AT NOSE OF 35 KT 8H JET MAX. MODELS SHOW THE POSSIBILITY THAT THE REMNANTS OF THESE STORMS COULD REACH INTO WRN/NCNTRL LAKE SUPERIOR AND NW UPPER MI LATE FRIDAY NIGHT INTO SATURDAY MORNING AND WILL MAINTAIN SOME LOW CHC POPS TO ACCOUNT FOR THIS POSSIBILITY. FOR THE MOST PART HOWEVER...EXPECT STORMS TO WEAKEN AS THEY MOVE INTO DRIER AND MORE STABLE AIR OVER LAKE SUPERIOR. WILL MAINTAIN A DIMINISHING TREND TO POPS THROUGH THE DAY ON SATURDAY AS SHORTWAVE EVENTUALLY MOVES NORTHEAST OF THE REGION AND TAKES BEST H85-H7 MOISTURE TRANSPORT WITH IT. UNDER PARTIAL SUNSHINE AND GUSTY SW WINDS TO 20-25 KTS...EXPECT TEMPS TO PUSH INTO THE LOWER 80S AWAY FM LK MICHIGAN WHERE IT SHOULD STAY IN THE UPPER 60S TO LOWER 70S. HUMIDITY WILL ALSO BE ON THE INCREASE. SATURDAY NIGHT...INCREASING WAA ESPECIALLY FROM THE WEST AFTER MIDNIGHT AHEAD OF ADVANCING SHORTWAVE FROM SCSNTRL CANADA WILL LEAD TO INCREASING CHCS OF SHRA/TSRA AS COLD FRONT/INSTABILITY AXIS WORKS EAST TOWARD UPPER GREAT LAKES. BASED ON WHERE BEST INSTABILITY IS LOCATED NEAR THE APPROACHING FRONTAL BOUNDARY IT LOOKS LIKE STORMS WOULD INITIATE OVER NRN MN OR NEAR THE CANADIAN BORDER. FORWARD PROPAGATING CORFIDI VECTORS AND DIFFLUENT THICKNESS PATTERN WOULD SUGGEST STORMS SOME STORMS COULD MOVE INTO WRN UPPER MI LATE SAT NIGHT SO WILL KEEP HIGHER CHC POPS OVER THESE AREAS WITH SLIGHT CHC POPS TO THE SE AND ERN CWA. GIVEN MARGINAL INSTABILITY PRESENT NOT EXPECTING ANY SEVERE STORMS. SUNDAY...BEST CHANCE OF SHRA/TSRA...POTENTIALLY STRONG OR SEVERE WILL BE SUNDAY AFTERNOON INTO SUNDAY EVENING AS WNW FLOW ALOFT CONTINUES TO SEND SHORTWAVES OVER THE AREA...AND SFC COLD FRONT SAGS SE ACROSS UPPER MI. KEY WILL BE HOW MUCH INSOLATION/HEATING AND SFC BASED INSTABILITY CAN BE REALIZED. MAIN NEGATIVE FACTOR IS H85 WINDS VEERING MORE WNW BEFORE ARRIVAL OF THE FRONT...CUTTING DOWN ON LOW-LEVEL THETA-E ADVECTION. BEST SHOT OF STRONGER STORMS WOULD PROBABLY BE OVER SOUTH CENTRAL AND SOUTHEAST CWA WHERE BETTER INSTABILITY AXIS OF NEAR 1000 J/KG OF MLCAPE WILL BE LOCATED. MAX TEMPS SHOULD BE WELL ABOVE NORMAL BASED ON MIXING DOWN H85 TEMPS UP TO +18C...EXPECT HIGHS WELL INTO THE 80S. IF THERE IS ENOUGH SUNSHINE...MAY SEE TEMPS NEAR 90 DEGREES. BEST SHOT OF SUCH WARM TEMPS WOULD PROBABLY BE SCNTRL CWA AWAY FM LK MICHIGAN. BEHIND SUNDAY/S COLD FROPA....TROUGHING ALOFT BECOMES RE-ESTABLISHED EARLY NEXT WEEK. NW FLOW ALOFT AND PERIODIC SHORTWAVES DROPPING THROUGH THE FLOW PATTERN COULD TRIGGER SCT SHRA AND MAYBE EVEN AN ISOLD TSRA AT TIMES MON INTO WED...ESPECIALLY INLAND WEST HALF. OTHERWISE...NORTH TO NORTH WINDS AT THE SFC WILL KEEP STABLIZED LAKE FLOW OVER MUCH OF THE CWA. TEMPS WILL BE BELOW NORMAL...WITH UPR 50S TO UPR 60S NEAR LK SUPERIOR AND READINGS IN THE 70S INLAND AND NEAR LK MICHIGAN. MODELS HINT AT RIDGING AND DRIER CONDITIONS MOVING IN FROM THE WEST BY THU WITH TEMPS LIKELY REBOUNDING CLOSER TO NORMAL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 739 AM EDT FRI JUL 4 2014 A HIGH PRESSURE RIDGE OVER THE AREA WILL LEAD TO VFR CONDITIONS THROUGH THE TAF PERIOD. LIGHT WINDS ASSOCIATED WITH THIS RIDGE WILL ALLOW LAKE BREEZES TO DEVELOP AND POTENTIALLY AFFECT ALL THREE SITES TODAY. KIWD MAY SWITCH AROUND FOR A COUPLE HOURS EARLY THIS AFTERNOON...BUT THEN SWITCH BACK TO THE SOUTHWEST. KCMX WILL SHIFT TO THE EAST LATE IN THE DAY...WHILE KSAW WILL SHIFT TO THE NORTHEAST AROUND NOON FROM THE LAKE SUPERIOR BREEZE AND THEN SWITCH TO THE SOUTHEAST LATE IN THE AFTERNOON AS THE LAKE MICHIGAN BREEZE MOVES THROUGH. SHOULD SEE SOME HIGH BASED DIURNAL CU (ALONG WITH SOME VIRGA) AT KSAW LATE THIS AFTERNOON. THE BEST OPPORTUNITY FOR SHOWERS AND THUNDERSTORMS WILL COME AFTER MIDNIGHT TONIGHT FOR KCMX...ALTHOUGH MOST OF THEM SHOULD STAY TO THE NORTHWEST OF THE SITE. FINALLY...MAY NEED LLWS AT KIWD OVERNIGHT TONIGHT...AS THE LOW LEVEL JET STRENGTHENS AHEAD OF THE LOW PRESSURE SYSTEM IN CENTRAL CANADA. SINCE WINDS ARE EXPECTED TO INCREASE AT THE SURFACE AND CREATE BORDERLINE VALUES...HAVE LEFT OUT FOR NOW. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 348 AM EDT FRI JUL 4 2014 A HIGH PRESSURE RIDGE OVER THE UPPER GREAT LAKES REGION WILL LEAD TO LIGHT WINDS TODAY AND INTO THIS EVENING. AS THE RIDGE SLIDES SOUTHEAST TONIGHT...WINDS WILL BE ON THE INCREASE OUT OF THE SOUTH AFTER MIDNIGHT TONIGHT AS A LOW PRESSURE SYSTEM MOVES EAST OUT OF CENTRAL CANADA. THIS LOW WILL STAY TO THE NORTH OF THE AREA THROUGH MONDAY AS IT MOVES INTO QUEBEC...BUT IT WILL DRAG A TROUGH ACROSS LAKE SUPERIOR SUNDAY NIGHT. EXPECT THE COOL LAKE SUPERIOR WATER TEMPERATURES TO HELP DEVELOP A MARINE LAYER THAT SHOULD KEEP WINDS BELOW 20KTS THROUGH SUNDAY. BEHIND THE TROUGH...WINDS WILL SHIFT TO THE NORTHWEST...BUT SHOULD REMAIN BELOW 20KTS AS A WEAK HIGH PRESSURE RIDGE QUICKLY MOVES INTO THE AREA BY MONDAY AFTERNOON. THE COMBINATION OF WARM MOIST AIR MOVING OVER LAKE SUPERIOR SATURDAY NIGHT INTO SUNDAY AND EXPECTED RAINFALL...WILL LEAD TO PATCHY TO AREAS OF FOG DEVELOPING OVER MAINLY THE NORTHERN HALF OF LAKE SUPERIOR SATURDAY NIGHT THROUGH SUNDAY NIGHT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ UPDATE...TITUS SHORT TERM...SRF LONG TERM...VOSS AVIATION...SRF MARINE...SRF
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
713 PM CDT SAT JUL 5 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 105 PM CDT SAT JUL 5 2014 LOOKS LIKE ANOTHER NIGHT WITH SOME POTENTIAL FOR SHRA/TSRA ACROSS THE REGION... BUT ONCE AGAIN THE QUESTION IS WHETHER THAT POTENTIAL WILL BE REALIZED. WE SHOULD SEE STORMS DEVELOP TO OUR WEST ONCE AGAIN THIS AFTERNOON... WHICH WILL LIKELY GROW UP SCALE INTO AN MCS. IF THIS OCCURS OVER NORTH DAKOTA AS MOST OF THE MODELS GUIDANCE SUGGESTS... IT LOOKS LIKE THE BULK OF IT WOULD TRANSLATE EAST ALONG THE THICKNESS CONTOURS AND MISS US TO THE NORTH. THERE ARE SOME HINTS IN THE CAM SOLUTIONS THAT A SECOND COMPLEX COULD DEVELOP FARTHER SOUTH OVER SOUTH DAKOTA... BUT IF THAT WERE TO OCCUR IT WOULD LIKELY TRANSLATE MORE SOUTHEASTWARD AND MISS US TO THE SOUTHWEST/SOUTH. A THIRD POTENTIAL FOR STORMS WOULD ACTUALLY BE SOONER... DURING LATE AFTERNOON/EARLY EVENING OVER OUR NORTH CENTRAL AND NORTHEAST CWFA... IF ANYTHING MANAGES TO DEVELOP IN THE CU FIELD CURRENTLY IN PLACE SOUTH OF THE ONGOING CONVECTION OVER NORTHEAST MINNESOTA. A COUPLE OF HOPWRF MEMBERS HAVE SUGGESTED THAT IS POSSIBLE... BUT THE OTHER MEMBERS AS WELL AS THE HRRR KEEP ANY OF THAT NORTH OF THE AREA. SO... OVERALL THERE REMAINS SOME POTENTIAL FOR ACTIVITY TO DEVELOP AND/OR MOVE INTO PORTIONS OF THE AREA TONIGHT... BUT IT IS BY NO MEANS A SLAM DUNK. WILL ALLOW POPS TO INCREASE ACROSS THE NORTH SOME DURING THE EVENING AND OVERNIGHT HOURS... WITH THAT AREA LOOKING TO HAVE THE BEST POTENTIAL TO SEE SOMETHING. ANYTHING THAT/S OVER THE AREA LATE TONIGHT WOULD SHIFT EAST IN THE MORNING... SO TRANSLATED SOME CHANCE POPS EASTWARD. WE WOULD THEN NEED TO LOOK TOWARD DEVELOPING ALONG/AHEAD OF THE COLD FRONT... WHICH WILL MOVE ACROSS THE AREA DURING THE LATE MORNING AND EARLY AFTERNOON ACCORDING TO THE MAJORITY OF THE GUIDANCE. THAT TIMING IS NOT PARTICULARLY FAVORABLE FOR DEVELOPMENT ACROSS OUR AREA... AND WOULD MAINLY POINT TOWARD AREAS EAST OF I-35 HAVING A CHANCE OF SEEING SOMETHING DURING THE AFTERNOON. SO... PUT THE HIGHEST POPS ON SUNDAY AFTERNOON ACROSS THE EASTERN PORTION OF THE AREA. SHOULD STORMS DEVELOP OVER THE AREA ON SUNDAY... THEY WOULD CERTAINLY HAVE SOME POTENTIAL TO BE SEVERE GIVEN MLCAPE VALUES AOA 2500 J/KG AND 0-6KM SHEAR AOA 35 KT... SO IT CERTAINLY BEARS WATCHING AND WILL BE MORE OF A CONCERN SHOULD THE FRONTAL TIMING WIND UP SLOWER. WE WILL MAKE A RUN AT 90 ON SUNDAY DEPENDING UPON HOW MUCH CLOUD COVER WE SEE OVER THE AREA... WHICH COULD BE HIGHLY VARIABLE DEPENDING ON ANY ISSUES FROM OVERNIGHT CONVECTIVE DEBRIS AND SHRA/TSRA DEVELOPMENT DURING THE DAY. THE FAIRLY EARLY FROPA DOESN/T APPEAR TO HAVE MUCH OF AN IMPACT ON THE HIGH TEMPERATURE POTENTIAL... WITH MIXING ACTUALLY LOOKING TO INCREASE BEHIND THE FRONT WHILE TEMPERATURES ALOFT ARE STILL SUPPORTIVE OF HIGHS NEAR 90. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 105 PM CDT SAT JUL 5 2014 THE THUNDERSTORM AND SEVERE WEATHER POTENTIAL SHOULD BE SOUTH AND EAST OF THE FORECAST AREA BY SUNDAY NIGHT ALONG THE AFOREMENTIONED COLD FRONT. GOOD MID-LEVEL DRYING WILL ACCOMPANY THE COLD ADVECTION SUNDAY NIGHT...BUT THE DRYING SHOULD BE SHORT LIVED WITH A WAVE DROPPING SOUTH OUT OF MANITOBA AND INTO ND/MN BY MONDAY AFTERNOON. A BIT MID DECK OF STRATUS OR STRATO-CU MIGHT ACT TO SUPPRESS SBCAPE...BUT THERE SHOULD BE DECENT RECOVERY IN ELEVATED INSTABILITY BY MONDAY AFTERNOON WITH STEEPENING MID-LEVEL LAPSE RATES. A MID-LEVEL SPEED MAX IS ALSO EXPECTED TO DROP SOUTH OUT OF THE HIGH PLAINS AND SHOULD INCREASE THE DEEP LAYER SHEAR ACROSS AT LEAST THE WESTERN FORECAST AREA. THEREFORE...STORMS EMBEDDED IN THE NORTHWEST FLOW SHOULD POSE A HAIL THREAT. WOULD NOT BE SURPRISED TO SEE THE SPC SLIGHT RISK SHIFTED A LITTLE FARTHER NORTH WITH THE NEXT UPDATE. WE HAVE INCREASED THE POPS TO 30-50% ACROSS MUCH OF THE FORECAST AREA...WITH THE IDEA OF AT LEAST SCATTERED STORM COVERAGE WITH THE ADVANCING SHORTWAVE AS THE TRIGGER. THE BEST TIME FRAME FOR STRONG TO SEVERE STORMS WOULD BE IN THE VERY LATE AFTERNOON AND EVENING. CYCLONICALLY CURVED LONG WAVE PATTERN LINGERS THROUGHOUT AT LEAST MID WEEK. THIS SHOULD CONTINUE TO REINFORCE THE COOL EARLY START TO THIS JULY...WHICH SITS BETWEEN 4 AND 7 DEGREES BELOW NORMAL FOR THE FIRST FEW DAYS IN CENTRAL MN AND WEST CENTRAL WI. HEIGHTS BUILD LATE IN THE WEEK...BUT THE FLOW STILL REMAINS W-NW AND THE THERMAL RIDGE OUT ACROSS THE WESTERN CONUS AND HIGH PLAINS WILL STRUGGLE TO ADVANCE EAST. THIS IS SUPPORTED BY THE CFS...05.12Z GFS/ECMWF AND THEIR CORRESPONDING ENSEMBLE MEMBERS WHICH INDICATES A NEAR NORMAL TEMPERATURE...BUT OVERALL DRY PATTERN FOR AT LEAST THE NEXT COUPLE WEEKS LOCALLY. IT DOES MEAN IF WE DONT REACH 90 TOMORROW...IT MAY BE SOME TIME BEFORE WE GET CLOSE TO THAT AGAIN. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 657 PM CDT SAT JUL 5 2014 CONFIDENCE IS HIGH FOR THE FIRST 6 HOURS OF THE TAF PERIOD BEING VFR... HOWEVER CONFIDENCE DECREASES SIGNIFICANTLY OVERNIGHT WITH THE POTENTIAL FOR LOW CLOUDS/FOG ACROSS WISCONSIN AND STORMS PUSHING INTO WESTERN MN FROM THE DAKOTAS. STORMS HAVE INDEED DEVELOPED ACROSS SOUTHERN NODAK AND FAR NORTHERN SODAK EARLY THIS EVENING...HOWEVER ACTIVITY HAS BEEN MUCH MORE ISOLATED THAN MODELS HAVE BEEN INDICATING. NONETHELESS...A VERY UNSTABLE ENVIRONMENT IS IN PLACE OVER THE PLAINS WHICH COULD ALLOW ADDITIONAL STORMS TO DEVELOP. RECENT MODEL RUNS ARE ALL OVER THE PLACE WITH WHERE THEY TAKE THESE STORMS...BUT THERE HAS BEEN A TREND TO BRING SOME INTO CENTRAL/SOUTHERN MN. THUS...INTRODUCED A TSRA PROB30 FOR THE MN TAF SITES LATE TONIGHT AND EARLY SUNDAY MORNING. OF SLIGHTLY MORE CONFIDENCE IS THE LOW CLOUD/FOG POTENTIAL OVER WI. STRATOCU FIELD OVER MUCH OF THE STATE IS CURRENTLY MVFR AND INCREASING MOISTURE OVERNIGHT IN CONJUNCTION WITH A COOLING OF THE BOUNDARY LAYER SHOULD BRING CIGS DOWN POSSIBLY TO IFR LEVELS AT EAU. WITH WINDS STILL 5-10 KT...NOT THINKING FOG WILL BE TOO MUCH OF AN ISSUE BUT SOME MINOR REDUCTIONS IN VISIBILITY IS POSSIBLE. KMSP...MAIN CONCERN IS THE CHANCE FOR TS LATE TONIGHT. SINCE MODELS DIFFER QUITE A BIT CONFIDENCE IS LOW...BUT THERE HAS BEEN A TENDENCY FOR THE HI RES MODELS TO BRING IN SOME TS AFTER 09Z. FOR NOW WENT WITH A PROB30...HOWEVER BY THE 03Z UPDATE IT WILL NEED TO BE UPGRADED TO TEMPO OR VICINITY...OR DROPPED ALTOGETHER SINCE IT WOULD BE WITHIN THE 9 HOUR PERIOD. THINK BY THE 03Z UPDATE CONFIDENCE WILL BE INCREASING ONE WAY OR ANOTHER. /OUTLOOK FOR KMSP/ MONDAY...VFR. WEST WIND 5 TO 15 KT. TUESDAY...VFR. NORTHWEST WIND 10 TO 20 KT. WEDNESDAY...VFR. WEST WIND 5 TO 10 KT. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...TRH LONG TERM...CLF AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
314 AM CDT FRI JUL 4 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 315 AM CDT FRI JUL 4 2014 MAIN CONCERN IS THE FOCUS OF SHRA/TSRA THIS MORNING...AND AGAIN LATER TODAY/TONIGHT AS A SHRTWV AND MOISTURE ADVECTION MOVE ACROSS THE REGION. MORNING SHORT TERM MODEL DEPICTION OF THE HRRR/HOPWRF/SPCWRF ALL INDICATED SHRA DEVELOPING ALONG THE BUFFALO RIDGE OF SD WHICH HAS MATERIALIZED AS OF 7Z. MODELS DO DEPICT THAT THIS ACTIVITY WILL SLOWLY MOVE E/NE ALONG THE DEVELOPING WAA/MOISTURE CONFLUENT REGION ACROSS WC/CENTRAL MN THIS MORNING. COVERAGE SHOULD REMAIN ISOLD/SCT DUE TO THE LIMITED AMT OF MOISTURE AVAILABLE AND STRENGTH OF THE MOISTURE ADVECTION. 03Z HOPWRF DOES SHOW HIGHER REFLECTIVITY MOVING AS FAR EAST AS EC MN DURING THE MID/LATE MORNING HRS BEFORE DISSIPATING. HOWEVER...THIS IS LIKELY SPRINKLES AT BEST DUE TO THE DRIER AIR ACROSS EASTERN MN THIS MORNING...AND THE TRAJECTORY OF THE STRONGEST MOISTURE ADVECTION TO THE N/NE OF MPX CWA. BY THE AFTN...MOST OF THE ACTIVITY SHOULD BE FOCUSED ACROSS NORTHERN MN AS OUR REGION BECOMES CAPPED WITH LITTLE IN THE WAY OF SFC FEATURES TO FOCUS ONGOING CONVECTION. LATER THIS EVENING...THE FOCUS SHOULD BE ALONG A POTENT SHRTWV MOVING ACROSS THE NORTHERN ROCKIES EARLY THIS MORNING. THE GFS/EC/GEM ALL CONSIDER THAT THERE SHOULD BE TWO AREAS OF CONVECTION TONIGHT. THE FIRST WILL LIKELY FOCUS ON THE LLJ IN SD/NE AND MOVING INTO IOWA. WHILE THE SECOND FEATURE WILL LIKELY FOCUS WITH AFTN DEVELOPMENT ACROSS NORTHERN MN. THERE REMAINS ENOUGH UNCERTAINTY TO CONTINUE ISOLD CONVECTION FROM WEST TO EAST TONIGHT AS BOTH K-INDEX VALUES AND A ELONGATED SHRTWV TROUGH MOVES ACROSS THE REGION. TEMPS TODAY WILL BE TRICKY IF MORE CLDS DEVELOP AND DO NOT DISSIPATED AS EXPECTED. AM LEANING TOWARD MID 80S IN THE WEST TO AROUND 80 IN THE EAST. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 315 AM CDT FRI JUL 4 2014 WEATHER MORE TYPICAL OF SUMMER WILL ARRIVE THIS WEEKEND AS NEARLY ZONAL FLOW BECOMES ESTABLISHED AND PLAINS CYCLOGENESIS INSTIGATES INCREASING TEMPERATURES AND HUMIDITY LEVELS. FAST ZONAL FLOW THEN PREVAILS THROUGH NEXT WEEK...WHICH WILL MEAN OCCASIONAL BOUTS OF SHOWERS AND THUNDERSTORMS AND AN INABILITY TO CONFIDENTLY ISOLATE AN ENTIRELY DRY DAY. THE WEEKEND WILL START OFF WITH HIGHS MEETING OR EXCEEDING CLIMATOLOGICAL NORMALS...WITH READINGS IN THE 80S EXPECTED ACROSS MOST OF THE AREA. WHILE THERE COULD BE ISOLATED NOCTURNALLY-DRIVEN SHOWERS AND THUNDERSTORMS TO START THE DAY...DO EXPECT A MID LEVEL CAP TO BE BUILDING IN DURING THE DAY ON SATURDAY /PER PROGGED 700MB TEMPS INCREASING TO AROUND +11C/ . HAVE INCLUDED A 20 POP FOR SAID ISOLATED ACTIVITY...BUT THE HIGHER CHANCES WILL ARRIVE ON SATURDAY NIGHT AND SUNDAY MORNING AS AN EXPECTED NOCTURNAL MESOSCALE CONVECTIVE SYSTEM DEVELOPS OVER NORTH DAKOTA AND SPILLS INTO CENTRAL MN ON THE NORTHERN PERIPHERY OF THE MID LEVEL CAP. HAVE INCLUDED 30-40 POPS ALONG/NORTH OF INTERSTATE 94 FROM CENTRAL MN INTO WI. AS THE MCS DECAYS ON SUNDAY...DO EXPECT SUFFICIENT CLEARING TO ALLOW TEMPERATURES TO MODERATE WELL INTO THE MID AND UPPER 80S. THE MOST LIKELY AREA TO THREATEN THE 90 DEGREE MARK WILL BE FROM WEST INTO SOUTH CENTRAL MN. MEANWHILE...DEWPOINTS IN THE LOWER 70S WILL CONTRIBUTE TO HEAT INDEX VALUES NEARING 95 DEGREES. AS THE TEMPERATURES WARM AND INSTABILITY INCREASES AHEAD OF THE COLD FRONT...MODELS INDICATE MLCAPES INCREASING TO OVER 4000 J/KG AND DEEP LAYER SHEAR VALUES CIRCA 40 KTS. THIS AREA IS CURRENTLY PROGGED TO BE JUST SKIRTING THE SOUTHERN FRINGES OF THE MPX CWA...BUT WILL CERTAINLY BE SUSCEPTIBILE TO MINOR AREAL SHIFTS DEPENDING ON HOW THE CONVECTIVE SCENARIO UNFOLDS EARLY SUNDAY. RIGHT NOW THE THREAT AREA FOR SEVERE STORMS ON SUNDAY PM APPEARS TO BE FROM MANKATO AND OWATONNA TO EAU CLAIRE AND POINTS SOUTH/EAST. LESS FOCI FOR ORGANIZED SHOWERS AND THUNDERSTORMS WILL THEN BE FOUND THROUGH NEXT WEEK IN THE WAKE OF SUNDAY/S SYSTEM. WHILE 20 POPS FOR SHOWERS AND THUNDERSTORMS ARE PEPPERING THE FORECAST NEARLY EVERY DAY NEXT WEEK...MANY AREAS WILL LIKELY REMAIN DRY ON SEVERAL OF THE DAYS...AND THOSE THAT DO RECEIVE RAIN WILL LIKELY EXPERIENCE FAIRLY LIGHT ASSOCIATED PRECIP AMOUNTS. TEMPERATURES THROUGH NEXT WEEK WILL BE MILD...WITH HIGHS HOVERING AROUND 80 DEGREES AND LOWS IN THE 50S/60S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1045 PM CDT THU JUL 3 2014 MAINLY VFR THROUGH THIS TAF SET...BUT THERE IS A VERY SMALL CHC THAT WESTERN SITES AROUND 12Z THIS MRNG COULD SEE MVFR CONDS DUE TO INCOMING -SHRA. A WEAK MIDLVL DISTURBANCE MOVING EWD FROM THE DAKOTAS INTO WRN MN NEAR DAYBREAK MAY SPAWN ISOLD TO SCTD -SHRA THAT MAY AFFECT KRWF-KAXN-KSTC. NOT EXPECTING MUCH IMPACT...AND AM ADVERTISING VFR -SHRA WITH THIS SET...BUT IF RAINFALL INTENSITIES DEVELOP PER THE LAST COUPLE HRRR AND HOPWRF MODEL RUNS...THERE COULD BE BRIEF MVFR CONDS. THIS PRECIPITATION LOOKS TO REMAIN IN WRN MN...THUS NOT IMPACTING KMSP-KRNH-KEAU SO HAVE LEFT THOSE SITES DRY. VFR CONDS THEN PREVAIL THRU THE DAY...BUT ANOTHER APCHG WAVE MAY PRODUCE ADDITIONAL ISOLD/SCTD -SHRA FRI EVE...AGAIN OVER MAINLY WRN TAF SITES. OTHERWISE...CLOUDS LIKELY IN THE MID- TO UPR- LEVELS...GRADUALLY INCRG IN COVERAGE. WINDS TO EVENTUALLY BECOME SLY AND BECOME BREEZY/GUSTY BY THIS AFTN. KMSP...VFR THROUGHOUT THIS FCST PKG. HOWEVER...ADDITIONAL MIDLVL CLOUDS ARE EXPECTED THAN FCST IN THE PREVIOUS FCST SET DUE TO A SLIGHTLY STRONG MIDLVL WAVE APCHG OVERNIGHT. THEREFORE...HAVE ADVERTISED BKN COVERAGE THROUGH THE OVERNIGHT HRS...WITH MULTIPLE LAYERS XPCTD AFTER DAYBREAK BUT WITH UPR LVL CEILINGS. CLOUDS GRADUALLY LOWER THRU THE DAY BUT NO PRECIP IS XPCTD DURG THIS SET. LGT/VRBL WINDS OVERNIGHT BECOME SLY BY THE MORNING PUSH THEN INCRS IN SPEED THRU THE AFTN HRS. /OUTLOOK FOR KMSP/ SAT...VFR. CHANCE OF MVFR SHRA/TSRA. WINDS S 10-15 KTS. SUN...VFR. CHANCE OF MVFR SHRA/TSRA. WINDS SW 5-10 KTS. MON...VFR. SLIGHT CHANCE OF MVFR SHRA/TSRA. WINDS NW 10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...JLT LONG TERM...LS AVIATION...JPC
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1051 PM CDT Sat Jul 5 2014 .UPDATE: Issued at 736 PM CDT Sat Jul 5 2014 Watching two areas this evening for convective trends. The first is the tail end of the departing MCV in north central Illinios. Boundary layer CAPE is on the increase from the southwest and could see a few storms skirt west central Illinois before midnight. The second area is near Kansas City, where majority of short term model guidance develops thunderstorms this evening. Some discrepancy as to which direction they move after they develop with the RAP moving them slowly east toward Central Missouri and the HRRR dropping them ever so slowly south. Have maintained some slight chance POPs for the northern CWA the next few hours as the MCV moves further away. Then have POPs slowly increase across central Missouri after midnight as we closely watch trends of KC convection. CVKING && .SHORT TERM: (Through Late Tonight) Issued at 348 PM CDT Sat Jul 5 2014 (Tonight) Complex of thunderstorms that persisted into early afternoon have finally began to diminish as they moved into limited instability to the east and little forcing to the south. This evening, the RAP and localWRF shows a rapid increase of low level moisture convergence and MUCAPE across the northern CWA which supports the going PoPS that we already have going in the forecast. Going temps fit in well with new agreeable MOS temps. Southern and eastern CWA are still in under the influence of a retreating ridge. Britt .LONG TERM: (Sunday through Next Saturday) Issued at 348 PM CDT Sat Jul 5 2014 (Sunday through Tuesday) Will keep a chance of thunderstorms going over the the area on Sunday, with the best chances going during the morning hours over the northeastern half of the CWA. This is where the strongest low level moisture convergence coincides with the weak ascent that a shortwave trough will provide as it passes through the area. This is supported by various simulated reflectivity of the convective allowing WRFs. The latest run of the GFS appears too deep with the trough because of convective feedback. Thunderstorms are also expected to develop over Iowa and northern Illinois later in the day and early evening in a very unstable airmass along a southeastward moving cold front. Will continue the chance of shower and thunderstorms over the area as these storms will be gradually diminishing in intensity through the night as they move into the CWA. By Monday and Tuesday this front will have become nearly stationary over the area under west northwesterly flow. Will keep high chance or low likely chances given the high CAPEs and the weak vort maxes moving the upper flow. It still looks like highs will reach the mid 90s over the central part of the CWA including the St. Louis metro area on Monday afternoon. Combine this with expected dewpoints in the lower 70s and heat index readings will top out around 100. (Wednesday through next Saturday) Both the GFS and ECMWF show the cold front pushing into the Mid South by Wednesday as the mean trough moves to the east of the area. However differences between the two models begin to show up by Friday as the ECMWF is much more aggressive in moving a deeper trough across the northern CONUS than the GFS. Consequently, the ECMWF brings a cold front across the area on Saturday while the GFS instead is building a ridge across the area. The ECMWF does not appear to have good continuity with this feature, so will not go along with this solution. Instead, will keep with a chance of thunderstorms over the southern CWA on Wednesday which will be the area in closest proximity to the front. Will also keep going chance of thunderstorms over the area on Friday as both models continue to indicate that the front will move through the CWA as a warm front. 850mb temperatures of +15C support below normal temperatures in the mid 80s for Wednesday and Thursday before temperatures climb back closer to normal by next Saturday. Britt && .AVIATION: (For the 06z TAFs through 06z Sunday Night) Issued at 1051 PM CDT Sat Jul 5 2014 Warm front remains stalled over northern portions of forecast area. So dealing with strato cu north of front at KUIN. Cigs should remain low end vfr and not dip down to ifr as front slowly lifts north. Southeast winds at KUIN to veer to the south when front slides through. Otherwise, rest of taf sites to remain vfr with mid and high clouds. As for winds, to persist from the south, then veer to the southwest by mid morning and pickup a bit ahead of next weather system. Some concern that activity that is firing up over west central MO could clip central MO, but confidence is low so left out mention at KCOU. Later today could see scattered activity, but once again confidence is low so kept tafs dry for now. Specifics for KSTL: Metro area to remain vfr with mid and high clouds. As for winds, to persist from the south, then veer to the southwest by 15z Sunday and pickup a bit ahead of next weather system. Later today could see scattered activity, but confidence is low so kept taf dry for now. Byrd && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
747 PM CDT Sat Jul 5 2014 .UPDATE: Issued at 736 PM CDT Sat Jul 5 2014 Watching two areas this evening for convective trends. The first is the tail end of the departing MCV in north central Illinios. Boundary layer CAPE is on the increase from the southwest and could see a few storms skirt west central Illinois before midnight. The second area is near Kansas City, where majority of short term model guidance develops thunderstorms this evening. Some discrepancy as to which direction they move after they develop with the RAP moving them slowly east toward Central Missouri and the HRRR dropping them ever so slowly south. Have maintained some slight chance POPs for the northern CWA the next few hours as the MCV moves further away. Then have POPs slowly increase across central Missouri after midnight as we closely watch trends of KC convection. CVKING && .SHORT TERM: (Through Late Tonight) Issued at 348 PM CDT Sat Jul 5 2014 (Tonight) Complex of thunderstorms that persisted into early afternoon have finally began to diminish as they moved into limited instability to the east and little forcing to the south. This evening, the RAP and localWRF shows a rapid increase of low level moisture convergence and MUCAPE across the northern CWA which supports the going PoPS that we already have going in the forecast. Going temps fit in well with new agreeable MOS temps. Southern and eastern CWA are still in under the influence of a retreating ridge. Britt .LONG TERM: (Sunday through Next Saturday) Issued at 348 PM CDT Sat Jul 5 2014 (Sunday through Tuesday) Will keep a chance of thunderstorms going over the the area on Sunday, with the best chances going during the morning hours over the northeastern half of the CWA. This is where the strongest low level moisture convergence coincides with the weak ascent that a shortwave trough will provide as it passes through the area. This is supported by various simulated reflectivity of the convective allowing WRFs. The latest run of the GFS appears too deep with the trough because of convective feedback. Thunderstorms are also expected to develop over Iowa and northern Illinois later in the day and early evening in a very unstable airmass along a southeastward moving cold front. Will continue the chance of shower and thunderstorms over the area as these storms will be gradually diminishing in intensity through the night as they move into the CWA. By Monday and Tuesday this front will have become nearly stationary over the area under west northwesterly flow. Will keep high chance or low likely chances given the high CAPEs and the weak vort maxes moving the upper flow. It still looks like highs will reach the mid 90s over the central part of the CWA including the St. Louis metro area on Monday afternoon. Combine this with expected dewpoints in the lower 70s and heat index readings will top out around 100. (Wednesday through next Saturday) Both the GFS and ECMWF show the cold front pushing into the Mid South by Wednesday as the mean trough moves to the east of the area. However differences between the two models begin to show up by Friday as the ECMWF is much more aggressive in moving a deeper trough across the northern CONUS than the GFS. Consequently, the ECMWF brings a cold front across the area on Saturday while the GFS instead is building a ridge across the area. The ECMWF does not appear to have good continuity with this feature, so will not go along with this solution. Instead, will keep with a chance of thunderstorms over the southern CWA on Wednesday which will be the area in closest proximity to the front. Will also keep going chance of thunderstorms over the area on Friday as both models continue to indicate that the front will move through the CWA as a warm front. 850mb temperatures of +15C support below normal temperatures in the mid 80s for Wednesday and Thursday before temperatures climb back closer to normal by next Saturday. Britt && .AVIATION: (For the 00z TAFs through 00z Sunday Evening) Issued at 636 PM CDT Sat Jul 5 2014 MCV to continue moving east away from taf sites, so will see dry vfr conditions through tonight. Could still see some activity fire up tomorrow, but coverage and timing hard to pin down so will keep tafs dry. Winds to persist from the south overnight, then veer a little to the southwest and pickup a bit by mid morning on Sunday. Specifics for KSTL: MCV to continue moving east away from metro area, so will see dry vfr conditions through tonight. Could still see some activity fire up tomorrow, but coverage and timing hard to pin down so will keep taf dry. Winds to persist from the south overnight, then veer a little to the southwest and pickup a bit by 15z Sunday. Byrd && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
645 PM CDT Sat Jul 5 2014 ...Updated for Aviation... .DISCUSSION... Issued at 309 PM CDT SAT JUL 5 2014 For today and tonight, the main forecast challenge will be whether or not convection can redevelop late this afternoon along remnant outflow boundaries/temperature gradients left over from morning convection. A decent shortwave trough will drop southward through the region tonight and could help spark this convection, but stable, cool air over most of the CWA may prevent thunderstorm development in spite of that wave. High-resolution models continue to initiate convection around 22-23z, but also continue to shift initiation west of the CWA where clear skies and breezy southwest winds have allowed temperatures to warm into the 90s. This seems like the most likely scenario given current conditions and cloud cover, so have trended PoPs downward this evening and tonight but still allowed for the possibility of precipitation with the shortwave trough. If storms do initiate over the forecast area tonight, the lack of upper-level flow and thus any deep layer shear will keep severe weather chances low. Hot temperatures in the mid 90s and the recent return to upper 60s dewpoints will result in 100-103 degree heat indices both tomorrow and Monday across most of the region. Does not look like a heat advisory is needed at this time, but will be something to watch with future forecast issuances. Next decent chance for thunderstorms will come Monday night into early Tuesday morning as a shortwave trough kicks a cold front through the region. Models have been fairly consistent with this feature, so continued to raise precipitation chances across the northern half of the CWA. Precipitation chances drop off south of I-70 as the shortwave trough exits the region to the east and forcing along the cold front diminishes on Tuesday, but cold pool interactions or any change in the track of the wave could change this slightly. Slightly cooler temperatures and drier conditions should follow behind the front, however; southerly surface flow, thunderstorm chances, warmer temperatures should return by late Thursday or Friday through the end of the period. && .AVIATION...(For the 00Z TAFS through 00Z Sunday Evening) Issued at 635 PM CDT SAT JUL 5 2014 For the 00Z TAFS...Convection is main concern this evening as there is a strong temperature gradient and weak boundary in the region from earlier storms. Surface temperature in Manhattan Kansas is currently 93F while it is only 83F at KMCI. There is ample moisture available and some moderate instability as well. The models are suggesting that the convection will rapidly evolve over the next few hours over extreme eastern portions of kansas and Nebraska and move south and east over the terminals through around 07Z. There still is a decent cap around 5K ft according to the RUC and visible satellite confirms. The BUFR soundings show this eroding within the next hour or two which will increase the chances for convection to evolve. Not confident in the cap eroding since the daylight is also waning. Expect storms will lose their surfaced-based instability with time. Given the mid level lapse rates are not impressive and all the above...the terminals should not fall below around 3SM and bases around 3K ft in storms that do form and move over the terminals tonight. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ DISCUSSION...Laflin AVIATION...Adolphson
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
636 PM CDT Sat Jul 5 2014 .SHORT TERM: (Through Late Tonight) Issued at 348 PM CDT Sat Jul 5 2014 (Tonight) Complex of thunderstorms that persisted into early afternoon have finally began to diminish as they moved into limited instability to the east and little forcing to the south. This evening, the RAP and localWRF shows a rapid increase of low level moisture convergence and MUCAPE across the northern CWA which supports the going PoPS that we already have going in the forecast. Going temps fit in well with new agreeable MOS temps. Southern and eastern CWA are still in under the influence of a retreating ridge. Britt .LONG TERM: (Sunday through Next Saturday) Issued at 348 PM CDT Sat Jul 5 2014 (Sunday through Tuesday) Will keep a chance of thunderstorms going over the the area on Sunday, with the best chances going during the morning hours over the northeastern half of the CWA. This is where the strongest low level moisture convergence coincides with the weak ascent that a shortwave trough will provide as it passes through the area. This is supported by various simulated reflectivity of the convective allowing WRFs. The latest run of the GFS appears too deep with the trough because of convective feedback. Thunderstorms are also expected to develop over Iowa and northern Illinois later in the day and early evening in a very unstable airmass along a southeastward moving cold front. Will continue the chance of shower and thunderstorms over the area as these storms will be gradually diminishing in intensity through the night as they move into the CWA. By Monday and Tuesday this front will have become nearly stationary over the area under west northwesterly flow. Will keep high chance or low likely chances given the high CAPEs and the weak vort maxes moving the upper flow. It still looks like highs will reach the mid 90s over the central part of the CWA including the St. Louis metro area on Monday afternoon. Combine this with expected dewpoints in the lower 70s and heat index readings will top out around 100. (Wednesday through next Saturday) Both the GFS and ECMWF show the cold front pushing into the Mid South by Wednesday as the mean trough moves to the east of the area. However differences between the two models begin to show up by Friday as the ECMWF is much more aggressive in moving a deeper trough across the northern CONUS than the GFS. Consequently, the ECMWF brings a cold front across the area on Saturday while the GFS instead is building a ridge across the area. The ECMWF does not appear to have good continuity with this feature, so will not go along with this solution. Instead, will keep with a chance of thunderstorms over the southern CWA on Wednesday which will be the area in closest proximity to the front. Will also keep going chance of thunderstorms over the area on Friday as both models continue to indicate that the front will move through the CWA as a warm front. 850mb temperatures of +15C support below normal temperatures in the mid 80s for Wednesday and Thursday before temperatures climb back closer to normal by next Saturday. Britt && .AVIATION: (For the 00z TAFs through 00z Sunday Evening) Issued at 636 PM CDT Sat Jul 5 2014 MCV to continue moving east away from taf sites, so will see dry vfr conditions through tonight. Could still see some activity fire up tomorrow, but coverage and timing hard to pin down so will keep tafs dry. Winds to persist from the south overnight, then veer a little to the southwest and pickup a bit by mid morning on Sunday. Specifics for KSTL: MCV to continue moving east away from metro area, so will see dry vfr conditions through tonight. Could still see some activity fire up tomorrow, but coverage and timing hard to pin down so will keep taf dry. Winds to persist from the south overnight, then veer a little to the southwest and pickup a bit by 15z Sunday. Byrd && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
633 PM CDT Sat Jul 5 2014 .SHORT TERM...(Tonight into Sunday) Issued at 254 PM CDT SAT JUL 5 2014 Currently, large expanse of high level clouds have enveloped much of the outlook area. This is blow off from a convective complex to our north. Over the past few hours, this area of showers and storms has rapidly decayed, with just a few lingering showers near northern portions of Miller/Maries counties. This activity will dissipate over the next hour or so, with additional development expected later. Temperatures have been affected, somewhat, by the high cloud coverage, with most locations in the upper 70s to lower 80s. The only exception is across extreme southeastern Kansas and western Missouri where mid/upper 80s are a bit more common. Anticipate that scattered TSRA will redevelop to the northwest of the CWA later today in line with the HRRR and NAM12...however models handling how this will propagate inconsistently. Given orientation of the moisture transport/low level Theta E would anticipate activity to build soutwestward into the night...then take on an easterly component toward morning as the relatively weak low level jet veers east. Questions for convection then on Sunday more of a question. Should be plenty of instability and even a bit of support from a dampening short wave. However rain may be hard to come by unless the overnight convection is able to generate an outflow boundary. .LONG TERM...(Sunday night through Friday) Issued at 254 PM CDT SAT JUL 5 2014 Warming trend will continue into Monday with areas over the west witnessing the highest heat indices of the season before heights start to fall and a wavy weak front arrives on Tuesday. Models have been consistent with convective development along the front Tuesday into early Wednesday as the front slowly descends into Arkansas. Questions continue as to how far south the front makes it into Arkansas and scattered storms may then continue along the Arkansas border through the end of the work week. && .AVIATION...(For the 00Z TAFS through 00Z Sunday Evening) Issued at 626 PM CDT SAT JUL 5 2014 The primary weather impact to aviation over the next 24 hours will be a chance for convection. The first round of overnight convection is forecast to move into the region from the west around sunrise, potentially impacting the Joplin aerodrome around sunrise. Another round of isolated thunderstorms is expected to form during the period of afternoon heating over southwestern Missouri. Outside of thunderstorms, winds are expected to be light and southerly through the period. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ SHORT TERM...Gagan/Runnels LONG TERM...Runnels AVIATION...Kardell
AREA FORECAST DISCUSSION
NWS GLASGOW MT
910 AM MDT FRI JUL 4 2014 .SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SUNDAY... FAIRLY CLEAR ACROSS THE CWA THIS MORNING BUT CHINOOK-TYPE MID AND HIGH CLOUDS ARE PARKED OVER CENTRAL MONTANA. CLOUDS SHOULD DRIFT MORE SOUTH THAN EAST TODAY AS DRIER AIR IS HEADED FOR THE NORTHERN ZONES FROM WA. LOWERED POPS FOR THE SOUTHERN ZONES AS BEST CHANCE FOR ANYTHING WOULD MOVE OFF THE SNOWY MTNS INTO PETROLEUM COUNTY. JAMBA PREVIOUS DISCUSSION... WATER VAPOR IMAGERY AND 500 MB HEIGHT FIELD SHOWS A WEATHER PATTERN IN SOMEWHAT OF A STATE OF CHANGE FOR THE NORTHERN HIGH PLAINS REGION. THE AMPLIFIED RIDGE WHICH WAS IN PLACE OVER EASTERN MONTANA EARLIER THIS WEEK HAS BEEN ALL BUT FLATTENED AND SHIFTED EASTWARD...LEAVING A NEARLY ZONAL FLOW ACROSS MONTANA WITH POSSIBLE A SLIGHT WEAK RIDGING EFFECT FROM THE SOUTH STILL IN PLACE. THROUGHOUT THE ENTIRE SHORT TERM FORECAST PERIOD...THIS UPPER- LEVEL FLOW REGIME WILL HOLD NEARLY CONSTANT WITH MAYBE A FEW EMBEDDED DISTURBANCES SETTING OFF SOME ISOLATED SHOWERS AND THUNDERSTORMS SOUTH OF THE MISSOURI RIVER TONIGHT...AND NORTH OF THE MISSOURI RIVER SATURDAY NIGHT. SUNDAY...NORTHWEST FLOW ALOFT RETURNS TO THE REGION KEEPING THE DAY MOSTLY SUNNY WITH RIDGING INFLUENCE FROM THE SOUTHWEST. IT SEEMS LATELY THAT THE MODEL SOLUTIONS ARE TRYING TO SQUEEZE AS MUCH PRECIPITATION OUT AS POSSIBLE...BUT OFTEN ARE FAR OVER- ESTIMATING THESE STORMS. THE HRRR IS MOST GUILTY OF THIS RECENTLY. WITH THAT IN MIND...FELT I COULD ONLY GIVE SLIGHT CHANCE POPS TO WHERE I COULD SEE SOME SEMBLANCE OF MODEL CONSENSUS AND CUT BACK AS MUCH AS POSSIBLE WHERE CONSENSUS SHOWED NO PRECIP. EXPECTING ANY DEVELOPING STORMS TO BE OF LITTLE CONSEQUENCE. BMICKELSON .LONG TERM...SUNDAY NIGHT THROUGH FRIDAY... FLAT RIDGE OVER THE WESTERN STATES AT THE BEGINNING OF NEXT WEEK EXPECTED TO RETROGRADE AND BUILD AS THE TROF OVER THE EASTERN STATES AMPLIFIES. A SERIES OF SHORTWAVES SLIDING ALONG THE CANADIAN BORDER BEFORE DIVING ACROSS THE NORTHERN PLAINS AND INTO THE EASTERN TROF WITH UPPER FLOW TURNING NORTHWEST FOR SUNDAY NIGHT AND MONDAY. WITH THE PROXIMITY OF THE WAVES AND A LITTLE MOISTURE AND INSTABILITY...SOME POTENTIAL FOR THUNDERSTORMS MAINLY IN THE NORTHEAST CORNER OF THE STATE. RIDGE BUILDS INTO THE NORTHERN ROCKIES MIDWEEK WITH HOT DRY AIR SPREADING NORTH FROM THE GREAT BASIN. UPPER LOW SPINS INTO WESTERN CANADA LATE IN THE WEEK TO FLATTEN THE RIDGE AGAIN. GFS AND EC BOTH PUSH WEAK FRONT ACROSS EASTERN MONTANA EARLY NEXT FRIDAY BUT KEEP THE AIRMASS HOT AND DRY. EBERT && .AVIATION... GENERALLY VFR. A WEAK FRONT WILL SLIDE ACROSS THE REGION TODAY WITH WINDS TURNING FROM SOUTHEAST TO WEST BY AFTERNOON. A FEW HIGH BASED THUNDERSTORMS COULD DEVELOP ALONG THIS FRONT IN THE YELLOWSTONE VALLEY DURING THE LATE AFTERNOON OR EVENING AND PRODUCE ERRATIC GUSTY WINDS. && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS GLASGOW MT
321 AM MDT FRI JUL 4 2014 .SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SUNDAY... WATER VAPOR IMAGERY AND 500 MB HEIGHT FIELD SHOWS A WEATHER PATTERN IN SOMEWHAT OF A STATE OF CHANGE FOR THE NORTHERN HIGH PLAINS REGION. THE AMPLIFIED RIDGE WHICH WAS IN PLACE OVER EASTERN MONTANA EARLIER THIS WEEK HAS BEEN ALL BUT FLATTENED AND SHIFTED EASTWARD...LEAVING A NEARLY ZONAL FLOW ACROSS MONTANA WITH POSSIBLE A SLIGHT WEAK RIDGING EFFECT FROM THE SOUTH STILL IN PLACE. THROUGHOUT THE ENTIRE SHORT TERM FORECAST PERIOD...THIS UPPER- LEVEL FLOW REGIME WILL HOLD NEARLY CONSTANT WITH MAYBE A FEW EMBEDDED DISTURBANCES SETTING OFF SOME ISOLATED SHOWERS AND THUNDERSTORMS SOUTH OF THE MISSOURI RIVER TONIGHT...AND NORTH OF THE MISSOURI RIVER SATURDAY NIGHT. SUNDAY...NORTHWEST FLOW ALOFT RETURNS TO THE REGION KEEPING THE DAY MOSTLY SUNNY WITH RIDGING INFLUENCE FROM THE SOUTHWEST. IT SEEMS LATELY THAT THE MODEL SOLUTIONS ARE TRYING TO SQUEEZE AS MUCH PRECIPITATION OUT AS POSSIBLE...BUT OFTEN ARE FAR OVER- ESTIMATING THESE STORMS. THE HRRR IS MOST GUILTY OF THIS RECENTLY. WITH THAT IN MIND...FELT I COULD ONLY GIVE SLIGHT CHANCE POPS TO WHERE I COULD SEE SOME SEMBLANCE OF MODEL CONSENSUS AND CUT BACK AS MUCH AS POSSIBLE WHERE CONSENSUS SHOWED NO PRECIP. EXPECTING ANY DEVELOPING STORMS TO BE OF LITTLE CONSEQUENCE. BMICKELSON .LONG TERM...SUNDAY NIGHT THROUGH FRIDAY... FLAT RIDGE OVER THE WESTERN STATES AT THE BEGINNING OF NEXT WEEK EXPECTED TO RETROGRADE AND BUILD AS THE TROF OVER THE EASTERN STATES AMPLIFIES. A SERIES OF SHORTWAVES SLIDING ALONG THE CANADIAN BORDER BEFORE DIVING ACROSS THE NORTHERN PLAINS AND INTO THE EASTERN TROF WITH UPPER FLOW TURNING NORTHWEST FOR SUNDAY NIGHT AND MONDAY. WITH THE PROXIMITY OF THE WAVES AND A LITTLE MOISTURE AND INSTABILITY...SOME POTENTIAL FOR THUNDERSTORMS MAINLY IN THE NORTHEAST CORNER OF THE STATE. RIDGE BUILDS INTO THE NORTHERN ROCKIES MIDWEEK WITH HOT DRY AIR SPREADING NORTH FROM THE GREAT BASIN. UPPER LOW SPINS INTO WESTERN CANADA LATE IN THE WEEK TO FLATTEN THE RIDGE AGAIN. GFS AND EC BOTH PUSH WEAK FRONT ACROSS EASTERN MONTANA EARLY NEXT FRIDAY BUT KEEP THE AIR MASS HOT AND DRY. EBERT && .AVIATION... GENERALLY VFR. A WEAK FRONT WILL SLIDE ACROSS THE REGION TODAY WITH WINDS TURNING FROM SOUTHEAST TO WEST BY AFTERNOON. A FEW HIGH BASED THUNDERSTORMS COULD DEVELOP ALONG THIS FRONT IN THE YELLOWSTONE VALLEY DURING THE LATE AFTERNOON OR EVENING AND PRODUCE ERRATIC GUSTY WINDS. && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS HASTINGS NE
642 PM CDT SAT JUL 5 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 305 PM CDT SAT JUL 5 2014 MAIN FORECAST CONCERNS WILL BE SHOWERS AND THUNDERSTORMS SOUTHEAST THIS AFTERNOON AND EVENING AND AGAIN LATE SUNDAY AFTERNOON...AND TEMPERATURES. CLOUDS HAVE ABOUT MOVED OUT OF THE FORECAST AREA THIS AFTERNOON BUT A FEW THIS AFTERNOON HAVE DEVELOPED ON THE EASTERN FRINGES OF THE FORECAST AREA AND PRODUCED A FEW SPRINKLES. AN UPPER LEVEL WAVE MOVES THROUGH THE AREA LATE THIS AFTERNOON AND EVENING. MODELS HAVE SOME DIFFERENCES IN THE STRENGTH OF THE WAVE AND WHAT HAPPENS AS IT MOVES THROUGH. THE NAM...THE RAP AND THE HRRR PRODUCE A LITTLE QPF/THUNDERSTORMS JUST TO THE SOUTHEAST OF THE FORECAST AREA FOR A BRIEF PERIOD LATE THIS AFTERNOON AND EARLY THIS EVENING. WITH THE SPRINKLES THAT FORMED EARLIER BELIEVE THAT A 20 PERCENT CHANCE COULD BE A GOOD IDEA IN THE FAR SOUTHEAST. NOT EXPECTING THERE TO BE MUCH BUT A FEW STORMS COULD DEVELOP. A SURFACE LOW AND COOL FRONT HAVE STARTED TO DEVELOP ON THE HIGH PLAINS THIS AFTERNOON. THIS FRONT APPROACHES THE FORECAST AREA TONIGHT AND MOVES INTO THE AREA DURING THE DAY SUNDAY. EVEN WITH THE FRONT MOVING INTO THE AREA THE TEMPERATURES ARE EXPECTED TO RISE WELL INTO THE 90S TO AROUND 100 DEGREES DURING THE DAY. AS THE FRONT MOVES THROUGH THE AREA...THERE IS A WEAK UPPER LEVEL WAVE THAT MOVES THROUGH THE AREA AS WELL. HAVE KEPT THE SMALL POPS IN FOR MUCH OF THE AREA DURING THE LATE AFTERNOON SUNDAY. THE MODELS HAVE DIFFERENCES ON THIS AS WELL. MANY OF THE MODELS ARE DRY...BUT A FEW SHOW SOME THUNDERSTORMS NEAR AND NORTH OF THE FRONT LATE IN THE AFTERNOON. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 305 PM CDT SAT JUL 5 2014 PATTERN: IT IS LOOKING DECIDEDLY MORE SUMMERLIKE. OVERALL THE MEAN LONGWAVE FLOW WILL FEATURE A WRN USA RIDGE/ERN USA TROF WITH SEASONABLE CHANGES IN AMPLITUDE. ONE THING IS CLEAR...WE HAVE TRANSITIONED TO A CONSIDERABLY DRIER PATTERN. THE PATTERN THAT BROUGHT THE VERY WET JUNE IS NO LONGER WITH US...AND ABOVE NORMAL HEIGHTS FCST OVER THE WRN AND CNTRL USA THRU MID-MONTH THREATEN SOME PERSISTENCE TO THIS DRYNESS. THE ONLY DECENT PROSPECT FOR MEANINGFUL RAIN FOR THE NEXT 7 DAYS IS MON NIGHT AND EVEN THEN NOT ALL AREAS WILL GET IT. EXPECT IRRIGATION WILL BE NECESSARY VERY SOON. ONE THING NOTED BY THE WPC /WX PREDICTION CTR AT NWSHQ/ IS TYPHOON NEOGURI FCST TO RECURVE IN THE WRN PACIFIC. ITS EXTRATROPICAL TRANSITION AND ABSORPTION INTO THE WESTERLIES COULD RESULT IN A PATTERN RE-ADJUSTMENT AROUND MID-MONTH. ALOFT: THE SUMMERTIME SUBTROPICAL HIGH HAS FINALLY DEVELOPED AND WILL BE OVER THE SW USA THRU MID-WEEK. STORMINESS OVER THE GULF OF AK WILL FORCE A TEMPORARY AMPLIFICATION OF THE RIDGE INTO WRN CANADA. THIS WILL LOWER HEIGHTS AND SEND A SHOT OF COOLER AIR INTO THE CNTRL/ERN USA THIS WEEK. THE ASSOCIATED TROF WILL SLIDE THRU MON NIGHT FOLLOWED BY CYCLONIC NW FLOW TUE-WED. A SHORTWAVE RIDGE WILL MOVE THRU THU AHEAD OF A TROF MOVING IN OFF THE PACIFIC. WHILE THE ENSEMBLE MEANS KEEP THIS TROF WILL ACTUALLY STAY N OF THE BORDER... ALLOWING HEIGHTS TO RISE AND THE SUBTROPICAL HIGH TO EXPAND ACROSS THE SRN 2/3 OF THE CONUS...AM NOT BUYING IT. THE PAST 2 EC/GEM/GFS CYCLES HAVE AMPLIFY THE PATTERN WITH THE ERN USA TROF BEING CARVED OUT AGAIN. THE 00Z EC ENSEMBLE CONTROL RUN SHOWS THIS VERY NICELY AND THIS IDEA FITS THE PATTERN. SURFACE: THE COOL FRONT THAT IS ADVANCING THRU THE FCST AREA SUN AFTERNOON WILL STALL OVER NRN KS MON...AWAITING A STRONGER SECOND FRONT THAT WILL SLIDE THRU MON NIGHT. THIS SECOND PUSH WILL FORCE THE COMPOSITE FRONT DEEPER INTO THE SRN PLAINS. COMFORTABLE HIGH PRES BUILDS IN TUE-WED WITH RETURN FLOW DEVELOPING THU AS THE HIGH HEADS INTO THE GREAT LAKES. LOW PRES WILL CROSS WRN CANADA DURING THIS TIME FRAME AND BEGIN DRAWING THE FRONT BACK N AS A WARM FRONT THU. FRI IT HEATS BACK UP IN THE WARM SECTOR...THEN A COOL FRONTAL PASSAGE FRI NIGHT OR SAT. HAZARDS: AN ISOLATED PROBABLY NON-SVR TSTM OR TWO IS POSSIBLE SUN NIGHT INTO MON. THE MAIN SHOW WILL BE MON NIGHT WITH LEGIT SVR POTENTIAL. BEYOND THAT...ANY TSTM DEVELOPMENT LOOKS UNORGANIZED AND IS LOW CONFIDENCE. THE DAILY DETAILS... UNCERTAINTY IS WAY ABOVE AVERAGE SUN NIGHT INTO MON. AM NOT IMPRESSED WITH THE TSTM POTENTIAL ALONG THIS FRONT. WHILE DEWPOINTS ARE IMPRESSIVE NOW...TOMORROW`S HEAT WILL MIX OUT THESE HIGH DWPTS WITH NO REPLENISHMENT. 12Z SOUNDINGS AROUND THE REGION THIS AM SHOW THERE ARE REALLY NO GOOD/DEEP BANDS OF MOISTURE. THIS LACK OF MOISTURE WILL MAKE IT MORE DIFFICULT TO BREAK THE CAP. 09Z SREF DOES SUGGEST PORTION OF THE NARROW RIBBON OF 10-12C 850 MB DWPTS ALONG THE FRONT WILL CIRCULATE ANTICYCLONICALLY BACK INTO THE REGION LATE SUN NIGHT INTO MON...WAITING TO INTERCEPT THE NEXT FRONT. BOTTOM LINE...MOST LOCATIONS WILL REMAIN DRY MOST OF THE TIME SUN NIGHT INTO MON. THIS FCST WOULD BETTER BE VIEWED FROM THE STANDPOINT THAT THERE IS AN 80% CHANCE THAT TSTMS WILL NOT FORM. "IF" AN ISOLATED TSTM OR TWO MANAGES TO DEVELOP...DEEP LAYER SHEAR WILL BE WEAK /10-15 KTS/. THIS SUGGESTS AT BEST NICKEL SIZE HAIL. LCL HEIGHTS WILL BE NEAR 10K FT WHICH WOULD THREATEN WIND GUSTS UP TO 50 MPH. MON NIGHT: A COOL FRONTAL PASSAGE WITH A TIGHT PRES GRADIENT BEHIND AND THE LLJ IN ADVANCE. CONSIDERABLE CONVERGENCE SHOULD RESULT IN TSTM DEVELOPMENT. THE PRECONVECTIVE ENVIRONMENT SHOULD HAVE 2000- 2500 J/KG OF MLCAPE WITH 40-45 KTS OF EFFECTIVE SHEAR. WE DO NEED TO WATCH POTENTIAL FOR INITIAL DEVELOPMENT FOR SUPERCELL POTENTIAL... BUT THE STRENGTH OF THE FORCING SHOULD RESULT IN RAPID DEVELOPMENT OF A SQUALL LINE WITH DAMAGING WIND BEING THE PRIMARY THREAT. GIVEN THE STRENGTH OF THE LOW-LEVEL SHEAR...EMBEDDED BOWS AND LEWP`S WILL BE POSSIBLE. WE HAVE NOTED THE SPC SLIGHT RISK FOR SVR WX AND WE ARE IN AGREEMENT. THIS FCSTR CONTS TO SEE TUE-THU COOLER THAN WHAT MEX MOS AND EVEN THE DAYS 4-7 INITIALIZATION HAVE BEEN ADVERTISING. THIS GUIDANCE HAS BEEN VERY RELUCTANT TO LOWER TEMPS. BASED ON ENSEMBLE TEMP ANOMALIES ...HAVE TRENDED THE FCST HIGHS CLOSER TO THE EC/GEM 2M TEMPS WHICH HAVE HAD A SIZABLE COOLDOWN FOR SEVERAL DAYS. TUE: CLEARING AS MON NIGHT`S MCS DEPARTS THE REGION. HIGHS HAVE BEEN LOWERED TO 77-86F...A LITTLE BELOW THE 4 AM GID FCST. THIS IS ROUGHLY 8F COOLER THAN NORMAL. THERE COULD BE A PERIOD OF WINDY CONDITIONS BEFORE NOON. WED: VERY NICE. TEMPS BEGIN CREEPING UP A LITTLE...BUT STILL 4-5F COOLER THAN NORMAL. WED NIGHT: GOOD LLJ DEVELOPMENT WITH A BURST OF THETA-E ADVECTION. COULD SEE A FEW SHWRS/TSTMS FORM WITH THE APPROACHING WARM FRONT. THU: QUESTIONABLE. IT ALL DEPENDS ON HOW QUICKLY WARM FRONTAL CLOUDINESS DEPARTS ALONG WITH ANY LINGERING EFFECTS FROM POSSIBLE MCS DEVELOPMENT WED NIGHT. THERE COULD ACTUALLY BE A SUBSTANTIAL TEMP GRADIENT FROM SW-NE ACROSS THE FCST AREA. WHILE AREAS FROM ORD- GREELEY-FULLERTON MAY BE JAMMED IN THE 70S...AREAS FROM BEAVER CITY- OSBORNE KS MAY BE IN THE UPPER 90S. FRI: ANOTHER THRUST OF BIG TIME HEAT IN THE WARM SECTOR. BELIEVE ODDS FAVOR 95-105F. LOOK FOR THIS TIME FRAME TO TREND HIGHER. FRI NIGHT OR SAT: POSSIBLY A COOL FRONTAL PASSAGE. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 635 PM CDT SAT JUL 5 2014 VFR CONDITIONS ARE EXPECTED TO PERSIST AT THE TERMINALS FOR THE NEXT 24 HOURS WITH ONLY A FEW MID/HIGH LEVEL CLOUDS EXPECTED THROUGH THE PERIOD. DO EXPECT TO SEE A MINOR WIND SHIFT FROM WEST TO NORTHERLY SUNDAY AFTERNOON...IN RESPONSE TO A PASSING WEAK COLD FRONT...BUT WINDS BOTH AHEAD AND BEHIND THE FRONT ARE EXPECTED TO BE LIGHT...AT 12KTS OR LESS...AS THE PRESSURE GRADIENT REMAINS WEAK ACROSS THE REGION. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...JCB LONG TERM...HALBLAUB AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1218 PM CDT FRI JUL 4 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 442 AM CDT FRI JUL 4 2014 SATELLITE AND 00Z UPPER AIR DATA SHOWING THE AREA UNDER NORTHWESTERLY FLOW ALOFT...SET UP BETWEEN A TROUGH CONTINUING TO PUSH TOWARD THE EAST COAST AND A RIDGE AXIS EXTENDING INTO THE ROCKIES FROM HIGH PRESSURE ROUGHLY OVER THE FOUR CORNERS REGION. AT THE SFC...NO NOTABLE CHANGES...THE CWA REMAINS BETWEEN HIGH PRESSURE CENTERED JUST EAST OF THE MISSOURI RIVER...AND A TROUGH OF LOW PRESSURE ALONG THE HIGH PLAINS...KEEPING THOSE SRLY WINDS IN PLACE. STARTING TO SEE A FEW SHOWERS/THUNDERSTORMS DEVELOPING NEAR THE WRN EDGE OF THE CWA...AS A WEAK DISTURBANCE AND INCREASED LIFT VIA A 30- 40ISH KT LLJ EDGES FURTHER EAST. SPC MESO PAGE SHOWING MUCAPE VALUES AROUND 1000 J/KG ALONG THAT WRN EDGE...BUT SHEAR IS FAIRLY LOW. EVEN NOW MODELS STILL VARY WITH THE EVOLUTION OF THIS MORNING...BUT WILL KEEP THE POPS GOING ACROSS THE CWA AND SEE HOW THINGS TREND OVER THE NEXT FEW HOURS. STILL CANT RULE OUT THE POSSIBILITY OF A FEW STRONG STORMS. WILL CONTINUE THE POPS INTO THE MORNING HOURS TODAY...BUT THINKING IS THAT ANY ACTIVITY WILL DIMINISH BY MIDDAY. SOME MODELS HINT AT THE POTENTIAL OF SOME ADDITIONAL ACTIVITY DEVELOPING TO OUR NORTH WITH ANOTHER WEAK DISTURBANCE LATER THIS MORNING INTO THE EARLY AFTERNOON HOURS...BUT AT THIS POINT UNLESS OTHER MODELS START TRENDING THAT WAIT NOT BUYING INTO THAT SOLUTION...AND KEPT THE MIDDAY/AFTERNOON HOURS DRY. BUT IT WILL BE SOMETHING THE DAY SHIFT NEED TO MONITOR...AND UPDATE IF IT DOES INDEED HAPPEN/AFFECT MAINLY NRN PORTIONS OF THE CWA. EXPECTING A BREEZY DAY TODAY AS THE PRESSURE GRADIENT ACROSS THE CWA TIGHTENS AND MIXING POTENTIAL INCREASES...SUSTAINED SPEEDS THIS AFTERNOON OF 20-25 MPH NOT OUT OF THE QUESTION ALONG WITH GUSTS OVER 30 MPH. EXPECTING AT LEAST PARTLY CLOUDY SKIES FOR MOST...WITH HIGHS REACHING INTO THE MID/UPPER 80S. OTHERWISE...THE MAIN FOCUS FOR THE SHORT TERM PERIOD TURNS TO THE WEST...AS THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON ALONG THE HIGH PLAINS ALONG THAT SFC TROUGH AXIS...AS YET ANOTHER UPPER LEVEL DISTURBANCE WORKS ITS WAY OUT OF THE ROCKIES AND ONTO THE PLAINS. THINK THE NAM AND SREF ARE TOO FAST WITH BRINGING THE ACTIVITY EAST...ALREADY AFFECTING THE WRN CWA BY 00Z THIS EVENING. OTHER MODELS...INCLUDING THE RAP/4KM WRF...SHOW THE BETTER CHANCES COMING POST 00Z. TRIMMED BACK THE POPS A BIT FOR THE FIRST FEW HOURS OF THE EVENING...LATEST RAP SHOWING EVEN AT 01Z THE BRUNT OF THE ACTIVITY IS W/NW OF THE CWA. OBVIOUSLY THINGS CAN TREND DIFFERENTLY WITH UPCOMING MODEL RUNS...ANOTHER THING FOR THE DAY SHIFT TO KEEP A CLOSE EYE ON...ESP WITH FOLKS WONDERING WHETHER THEY WILL BE ABLE TO SEE THEIR FIREWORKS SHOWS. WHILE POPS WILL BE ON THE INCREASE DURING THE MID/LATE EVENING HOURS...STILL SOME UNCERTAINTY WITH THE OVERALL COVERAGE...WHICH MAY BE MORE SCATTERED IN NATURE...SO MADE ONLY MINOR TWEAKS TO THE POPS. THAT UNCERTAINTY EVEN CONTINUES INTO THE OVERNIGHT/EARLY MORNING HOURS...THE UPPER LEVEL DISTURBANCE CONTINUES PUSHING EAST BUT MODELS VARY WITH WHERE THE NOSE OF THE LLJ AND BETTER CONVERGENCE WILL END UP...WITH SOME SHOWING ACTIVITY PICKING BACK UP OVER OUR ERN COUNTIES. PLENTY OF DETAINS YET TO IRON OUT...EVEN THIS CLOSE TO THE THUNDERSTORM CHANCES. THINKING AS FAR AS STRONG/SEVERE WEATHER GOES HAS NOT CHANGED MUCH...AS THE SHEAR/INSTABILITY COMBO KEEPS THAT POTENTIAL IN PLACE ACROSS THE ENTIRE CWA. LARGE HAIL/DAMAGING WINDS STILL LOOKING TO THE PRIMARY HAZARDS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 442 AM CDT FRI JUL 4 2014 THE MOST NOTABLE WEATHER STORY OF THIS 6-DAY PERIOD IS A PROLONGED STRETCH OF NEAR-NORMAL TO ABOVE NORMAL SUMMER HEAT...MEANING HIGH TEMPERATURES ON MOST DAYS ACROSS THE MAJORITY OF THE CWA ARE GENERALLY FORECAST TO RANGE SOMEWHERE BETWEEN THE MID-80S AND LOW-90S...WITH PORTIONS OF THE AREA EXCEEDING THIS RANGE ESPECIALLY ON SUNDAY. FOR THOSE WHO ENJOYED THESE PAST FEW BELOW NORMAL DAYS...THIS WEEKEND ESPECIALLY WILL BE A RUDE REMINDER THAT IT IS IN FACT JULY. THE INCREASING TEMPS WILL ALSO BE ACCOMPANIED BY A NOTICEABLE INCREASE IN DEWPOINTS/HUMIDITY AS WELL...WITH DEWS FORECAST TO AVERAGE AT LEAST WELL INTO THE 60S FOR THE MAJORITY OF THE NEXT WEEK...WITH THE CLIMATOLOGICALLY FAVORED NORTHEAST QUADRANT OF THE CWA MOST FAVORED TO SEE DEWPOINTS OCCASIONALLY REACH OR SLIGHTLY EXCEED THE MORE- OPPRESSIVE 70 DEGREE MARK. AS FOR BOTH ACTUAL AIR TEMPERATURE AND HEAT INDEX VALUES...SUNDAY IS CURRENTLY SLATED TO BE THE OVERALL- HOTTEST DAY OF THE SUMMER SO FAR WITHIN THE CWA...AND MADE RELATIVELY LITTLE CHANGE TO PREVIOUS FORECAST WITH ACTUAL TEMPS AIMED FROM THE MID-90S NORTHEAST TO THE UPPER 90S-100 SOUTH/SOUTHWEST. AS FOR HEAT INDEX VALUES SUNDAY AFTERNOON...ALTHOUGH THE LATEST FORECAST KEEPS ALL AREAS AT LEAST SLIGHTLY BELOW HEAT ADVISORY CRITERIA OF 105+ DEGREES...THERE IS A DECENT PERCENTAGE OF THE CWA NOW FORECAST TO OBSERVE VALUES IN THE 100-104 RANGE...SO HAVE KEPT THIS NEAR-ADVISORY HEAT INDEX FORECAST IN THE HAZARDOUS WEATHER OUTLOOK (HWOGID). FORTUNATELY...SUNDAY IS THE ONLY DAY OUT OF THESE 6 FORECAST TO BREACH THE 100+ HEAT INDEX MARK...THANKS TO A WEAK COLD FRONTAL PASSAGE EXPECTED LATE SUNDAY NIGHT INTO MONDAY TEMPERING THE HEAT A BIT...AND ALSO ALLOWING SURFACE BREEZES TO PREVAIL FROM MORE OF AN EAST-SOUTHEAST DIRECTION THROUGH MUCH OF NEXT WEEK INSTEAD OF THE PREVALENT SOUTHERLY DIRECTION EXPECTED THIS WEEKEND. SWITCHING GEARS TO SHOWER/THUNDERSTORM CHANCES...FOR BETTER OR WORSE THESE 6 DAYS SIGNAL A GENERAL RETURN TO THE FORECAST PATTERN OF 1-2 WEEKS AGO...MEANING THAT THERE ARE A MULTITUDE OF FAIRLY LOW 20-30 POPS IN THE FORECAST DURING THE MAJORITY OF 12-HOUR PERIODS...BUT VERY FEW OF THESE PERIODS WILL PROBABLY END UP HAVING WIDESPREAD COVERAGE SO BE SURE TO KEEP THESE MYRIAD CHANCES ESPECIALLY BEYOND THE FIRST FEW DAYS IN PERSPECTIVE. THAT BEING SAID...THE ONLY PERIOD THAT CURRENTLY FEATURES MORE WIDESPREAD COVERAGE OF SOMEWHAT HIGHER 30-40 POPS IS MONDAY NIGHT...SO IF TRENDS HOLD THIS MAY END UP BEING THE OVERALL-BEST CHANCE OF RAIN FOR THE MAJORITY OF THE AREA. AS FOR SEVERE WEATHER CHANCES...OBVIOUSLY GIVEN THE RETURN OF TYPICAL SUMMER HEAT/HUMIDITY THERE WILL BE PLENTY OF INSTABILITY AROUND MOST OF THE TIME...BUT ALSO TYPICAL OF SUMMER THE MAJORITY OF THE TIME WILL PROBABLY HAVE NO BETTER THAN MODEST DEEP-LAYER WIND SHEAR AND/OR CAPPING ISSUES. AS A RESULT...THERE IS FAR TOO MUCH UNCERTAINTY TO SAY MUCH ABOUT ANY ORGANIZED SEVERE RISK BEYOND THIS WEEKEND...BUT PER THE STORM PREDICTION CENTER DAY 3 OUTLOOK THERE COULD BE AT LEAST A CONDITIONAL SEVERE THREAT FOR LATE SUNDAY AFTERNOON INTO SUNDAY NIGHT ALONG AND PROBABLY MORE-SO BEHIND THE AFOREMENTIONED COLD FRONT SAGGING INTO NEB ZONES FROM THE NORTH. ALSO...BACKING UP TO RIGHT AWAY SATURDAY MORNING...CANNOT RULE OUT THE POSSIBILITY OF A FEW STRONG STORMS LINGERING IN EASTERN ZONES FROM THE FRIDAY NIGHT ACTIVITY DESCRIBED IN THE SHORT TERM SECTION ABOVE...BUT ODDS ARE THAT ANY LEGITIMATE SEVERE THREAT SHOULD BE OVER BY THEN. GETTING MORE INTO METEOROLOGICAL DETAIL AND TAKING THINGS IN 24-HOUR BLOCKS... SATURDAY DAYTIME-SATURDAY NIGHT...IN THE MID-UPPER LEVEL PICTURE THE SUBTROPICAL RIDGE CENTERED OVER THE SOUTHWESTERN CONUS REMAINS THE DOMINANT INFLUENCE ON CENTRAL PLAINS WEATHER...BUT THE DAYTIME HOURS START OUT WITH THE LINGERING DEPARTURE OF A LOW-AMPLITUDE SHORTWAVE TROUGH FROM FRIDAY NIGHT. AS A RESULT...JUST CANNOT RULE OUT SOME STORMS LINGERING OVER EASTERN ZONES INTO THE MID-MORNING HOURS...AND THUS LARGELY MAINTAINED LOW POPS SATURDAY MORNING FROM THE PREVIOUS FORECAST. BY SATURDAY AFTERNOON INTO ESPECIALLY SATURDAY NIGHT...THE MID-UPPER RIDGE RE-ESTABLISHES ITSELF A BIT AND TURNS THE FLOW MORE NORTHERLY ALOFT OVER THE LOCAL AREA WITH A LACK OF DISCERNIBLE SHORTWAVE TROUGHS. AS A RESULT...DESPITE PLENTY OF INSTABILITY OVER THE AREA...WILL CONTINUE TO SIDE WITH THE CONSENSUS OF MOST MODELS AND KEEP SATURDAY AFTERNOON-NIGHT VOID OF SHOWER/THUNDERSTORM POPS AT THIS TIME...ALTHOUGH COULD AT LEAST SEE SOME ACTIVITY COME VERY CLOSE TO AFFECTING THE CWA. HIGH TEMPS AIMED FROM LOW 90S NORTHEAST TO MID-UPPER 90S SOUTH/SOUTHWEST. SUNDAY DAYTIME-SUNDAY NIGHT...THE ENHANCED HEAT ASPECT AND TO SOME EXTENT THE POSSIBLE STRONG-SEVERE STORM RISK LATE IN THE DAY AND LIKELY MORE SO INTO THE EVENING HAS ALREADY BEEN COVERED ABOVE. IN THE MID-UPPER LEVELS THE RIDGE IS FLATTENED A BIT BY THE PASSAGE OF A PROGRESSIVE SHORTWAVE PASSING BY TO THE NORTH GENERALLY ALONG THE CANADA BORDER. THIS IN TURN ALLOWS A WEAK BUT DECENTLY-DEFINED SURFACE COLD FRONT TO SINK SOUTHWARD INTO AND POSSIBLY ALL THE WAY THROUGH THE CWA DURING THE AFTERNOON/EVENING...POSSIBLY PROMOTING VIGOROUS STORM DEVELOPMENT PRIMARILY WITHIN THE NORTHERN 1/2 OF THE CWA. PLENTY OF UNCERTAINTY HERE THOUGH. MONDAY DAYTIME-MONDAY NIGHT...A BIT STRONGER NORTHWESTERLY FLOW OVERSPREADS THE LOCAL AREA AS THE UPPER JET CORE SINKS FARTHER SOUTHWARD IN RESPONSE TO REINFORCING SHORTWAVE ENERGY DROPS THROUGH THE UPPER MIDWEST. MAINTAINED TOKEN 20 POPS THROUGH THE DAY BUT AS ALREADY MENTIONED THE NIGHT PERIOD FEATURES THE OVERALL-HIGHEST POPS OF THE LONG-TERM PERIOD IN THE 30-40 RANGE AS BOTH THE ECMWF/GFS ARE FAIRLY INSISTENT IN SPARKING POTENTIALLY VIGOROUS AND MORE WIDESPREAD CONVECTION. HIGH TEMPS TEMPER A BIT FROM SUNDAY...GENERALLY AIMED UPPER 80S NORTH-MID 90S SOUTH. TUESDAY DAYTIME-TUESDAY NIGHT...THESE 24 HOURS REMAIN BLANKETED WITH MAINLY TOKEN 20 POPS AS THE CENTRAL PLAINS REMAINS ALONG THE POTENTIALLY SOMEWHAT ACTIVE INTERFACE OF THE NORTHWEST FLOW REGIME DIRECTED ALONG THE INTERFACE BETWEEN THE SOUTHWEST CONUS RIDGE AND A VIGOROUS SOUTHEAST CANADA TROUGH. HIGH TEMPS MID 80S NORTH-LOW 90S SOUTH. WEDNESDAY DAYTIME-WEDNESDAY NIGHT...NOT MUCH CHANGE IN THE OVERALL PATTERN AS NORTHWEST FLOW ALOFT REMAIN IN PLACE. ALTHOUGH THERE ARE SOME INDICATIONS THAT MOST CONVECTION IN THE REGION COULD FOCUS SOUTH AND/OR WEST OF THE CWA...BLANKET COVERAGE OF 20 POPS CONTINUES DUE TO THE UNCERTAINTY. HIGH TEMPS MID 80S NORTH-LOW 90S SOUTH. THURSDAY DAYTIME...ALTHOUGH SLIGHT POPS CONTINUE AREA-WIDE FOR NOW...THERE ARE VERY EARLY INDICATIONS THAT FLOW ALOFT MAY TURN MORE ZONAL AND ALLOW WARMER ALOFT TO PUSH IN FROM THE WEST...POTENTIALLY USHERING IN AT LEAST A BRIEF STRETCH THAT MAY NOT EVEN BE WORTHY OF 20 POPS IN LATER FORECASTS. HIGH TEMPS VERY PRELIMINARILY AIMED MID 80S NORTH-LOW 90S SOUTH...VERY SIMILAR TO TUES-WED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1214 PM CDT FRI JUL 4 2014 MID LEVEL CLOUDS WILL LINGER MUCH OF THE PERIOD. THERE COULD BE A FEW THUNDERSTORMS AROUND LATER THIS EVENING. GUSTY SOUTH WINDS WILL LET UP A LITTLE DURING THE NIGHT. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...ADO LONG TERM...PFANNKUCH AVIATION...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
628 AM CDT FRI JUL 4 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 442 AM CDT FRI JUL 4 2014 SATELLITE AND 00Z UPPER AIR DATA SHOWING THE AREA UNDER NORTHWESTERLY FLOW ALOFT...SET UP BETWEEN A TROUGH CONTINUING TO PUSH TOWARD THE EAST COAST AND A RIDGE AXIS EXTENDING INTO THE ROCKIES FROM HIGH PRESSURE ROUGHLY OVER THE FOUR CORNERS REGION. AT THE SFC...NO NOTABLE CHANGES...THE CWA REMAINS BETWEEN HIGH PRESSURE CENTERED JUST EAST OF THE MISSOURI RIVER...AND A TROUGH OF LOW PRESSURE ALONG THE HIGH PLAINS...KEEPING THOSE SRLY WINDS IN PLACE. STARTING TO SEE A FEW SHOWERS/THUNDERSTORMS DEVELOPING NEAR THE WRN EDGE OF THE CWA...AS A WEAK DISTURBANCE AND INCREASED LIFT VIA A 30- 40ISH KT LLJ EDGES FURTHER EAST. SPC MESO PAGE SHOWING MUCAPE VALUES AROUND 1000 J/KG ALONG THAT WRN EDGE...BUT SHEAR IS FAIRLY LOW. EVEN NOW MODELS STILL VARY WITH THE EVOLUTION OF THIS MORNING...BUT WILL KEEP THE POPS GOING ACROSS THE CWA AND SEE HOW THINGS TREND OVER THE NEXT FEW HOURS. STILL CANT RULE OUT THE POSSIBILITY OF A FEW STRONG STORMS. WILL CONTINUE THE POPS INTO THE MORNING HOURS TODAY...BUT THINKING IS THAT ANY ACTIVITY WILL DIMINISH BY MIDDAY. SOME MODELS HINT AT THE POTENTIAL OF SOME ADDITIONAL ACTIVITY DEVELOPING TO OUR NORTH WITH ANOTHER WEAK DISTURBANCE LATER THIS MORNING INTO THE EARLY AFTERNOON HOURS...BUT AT THIS POINT UNLESS OTHER MODELS START TRENDING THAT WAIT NOT BUYING INTO THAT SOLUTION...AND KEPT THE MIDDAY/AFTERNOON HOURS DRY. BUT IT WILL BE SOMETHING THE DAY SHIFT NEED TO MONITOR...AND UPDATE IF IT DOES INDEED HAPPEN/AFFECT MAINLY NRN PORTIONS OF THE CWA. EXPECTING A BREEZY DAY TODAY AS THE PRESSURE GRADIENT ACROSS THE CWA TIGHTENS AND MIXING POTENTIAL INCREASES...SUSTAINED SPEEDS THIS AFTERNOON OF 20-25 MPH NOT OUT OF THE QUESTION ALONG WITH GUSTS OVER 30 MPH. EXPECTING AT LEAST PARTLY CLOUDY SKIES FOR MOST...WITH HIGHS REACHING INTO THE MID/UPPER 80S. OTHERWISE...THE MAIN FOCUS FOR THE SHORT TERM PERIOD TURNS TO THE WEST...AS THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON ALONG THE HIGH PLAINS ALONG THAT SFC TROUGH AXIS...AS YET ANOTHER UPPER LEVEL DISTURBANCE WORKS ITS WAY OUT OF THE ROCKIES AND ONTO THE PLAINS. THINK THE NAM AND SREF ARE TOO FAST WITH BRINGING THE ACTIVITY EAST...ALREADY AFFECTING THE WRN CWA BY 00Z THIS EVENING. OTHER MODELS...INCLUDING THE RAP/4KM WRF...SHOW THE BETTER CHANCES COMING POST 00Z. TRIMMED BACK THE POPS A BIT FOR THE FIRST FEW HOURS OF THE EVENING...LATEST RAP SHOWING EVEN AT 01Z THE BRUNT OF THE ACTIVITY IS W/NW OF THE CWA. OBVIOUSLY THINGS CAN TREND DIFFERENTLY WITH UPCOMING MODEL RUNS...ANOTHER THING FOR THE DAY SHIFT TO KEEP A CLOSE EYE ON...ESP WITH FOLKS WONDERING WHETHER THEY WILL BE ABLE TO SEE THEIR FIREWORKS SHOWS. WHILE POPS WILL BE ON THE INCREASE DURING THE MID/LATE EVENING HOURS...STILL SOME UNCERTAINTY WITH THE OVERALL COVERAGE...WHICH MAY BE MORE SCATTERED IN NATURE...SO MADE ONLY MINOR TWEAKS TO THE POPS. THAT UNCERTAINTY EVEN CONTINUES INTO THE OVERNIGHT/EARLY MORNING HOURS...THE UPPER LEVEL DISTURBANCE CONTINUES PUSHING EAST BUT MODELS VARY WITH WHERE THE NOSE OF THE LLJ AND BETTER CONVERGENCE WILL END UP...WITH SOME SHOWING ACTIVITY PICKING BACK UP OVER OUR ERN COUNTIES. PLENTY OF DETAINS YET TO IRON OUT...EVEN THIS CLOSE TO THE THUNDERSTORM CHANCES. THINKING AS FAR AS STRONG/SEVERE WEATHER GOES HAS NOT CHANGED MUCH...AS THE SHEAR/INSTABILITY COMBO KEEPS THAT POTENTIAL IN PLACE ACROSS THE ENTIRE CWA. LARGE HAIL/DAMAGING WINDS STILL LOOKING TO THE PRIMARY HAZARDS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 442 AM CDT FRI JUL 4 2014 THE MOST NOTABLE WEATHER STORY OF THIS 6-DAY PERIOD IS A PROLONGED STRETCH OF NEAR-NORMAL TO ABOVE NORMAL SUMMER HEAT...MEANING HIGH TEMPERATURES ON MOST DAYS ACROSS THE MAJORITY OF THE CWA ARE GENERALLY FORECAST TO RANGE SOMEWHERE BETWEEN THE MID-80S AND LOW-90S...WITH PORTIONS OF THE AREA EXCEEDING THIS RANGE ESPECIALLY ON SUNDAY. FOR THOSE WHO ENJOYED THESE PAST FEW BELOW NORMAL DAYS...THIS WEEKEND ESPECIALLY WILL BE A RUDE REMINDER THAT IT IS IN FACT JULY. THE INCREASING TEMPS WILL ALSO BE ACCOMPANIED BY A NOTICEABLE INCREASE IN DEWPOINTS/HUMIDITY AS WELL...WITH DEWS FORECAST TO AVERAGE AT LEAST WELL INTO THE 60S FOR THE MAJORITY OF THE NEXT WEEK...WITH THE CLIMATOLOGICALLY FAVORED NORTHEAST QUADRANT OF THE CWA MOST FAVORED TO SEE DEWPOINTS OCCASIONALLY REACH OR SLIGHTLY EXCEED THE MORE- OPPRESSIVE 70 DEGREE MARK. AS FOR BOTH ACTUAL AIR TEMPERATURE AND HEAT INDEX VALUES...SUNDAY IS CURRENTLY SLATED TO BE THE OVERALL- HOTTEST DAY OF THE SUMMER SO FAR WITHIN THE CWA...AND MADE RELATIVELY LITTLE CHANGE TO PREVIOUS FORECAST WITH ACTUAL TEMPS AIMED FROM THE MID-90S NORTHEAST TO THE UPPER 90S-100 SOUTH/SOUTHWEST. AS FOR HEAT INDEX VALUES SUNDAY AFTERNOON...ALTHOUGH THE LATEST FORECAST KEEPS ALL AREAS AT LEAST SLIGHTLY BELOW HEAT ADVISORY CRITERIA OF 105+ DEGREES...THERE IS A DECENT PERCENTAGE OF THE CWA NOW FORECAST TO OBSERVE VALUES IN THE 100-104 RANGE...SO HAVE KEPT THIS NEAR-ADVISORY HEAT INDEX FORECAST IN THE HAZARDOUS WEATHER OUTLOOK (HWOGID). FORTUNATELY...SUNDAY IS THE ONLY DAY OUT OF THESE 6 FORECAST TO BREACH THE 100+ HEAT INDEX MARK...THANKS TO A WEAK COLD FRONTAL PASSAGE EXPECTED LATE SUNDAY NIGHT INTO MONDAY TEMPERING THE HEAT A BIT...AND ALSO ALLOWING SURFACE BREEZES TO PREVAIL FROM MORE OF AN EAST-SOUTHEAST DIRECTION THROUGH MUCH OF NEXT WEEK INSTEAD OF THE PREVALENT SOUTHERLY DIRECTION EXPECTED THIS WEEKEND. SWITCHING GEARS TO SHOWER/THUNDERSTORM CHANCES...FOR BETTER OR WORSE THESE 6 DAYS SIGNAL A GENERAL RETURN TO THE FORECAST PATTERN OF 1-2 WEEKS AGO...MEANING THAT THERE ARE A MULTITUDE OF FAIRLY LOW 20-30 POPS IN THE FORECAST DURING THE MAJORITY OF 12-HOUR PERIODS...BUT VERY FEW OF THESE PERIODS WILL PROBABLY END UP HAVING WIDESPREAD COVERAGE SO BE SURE TO KEEP THESE MYRIAD CHANCES ESPECIALLY BEYOND THE FIRST FEW DAYS IN PERSPECTIVE. THAT BEING SAID...THE ONLY PERIOD THAT CURRENTLY FEATURES MORE WIDESPREAD COVERAGE OF SOMEWHAT HIGHER 30-40 POPS IS MONDAY NIGHT...SO IF TRENDS HOLD THIS MAY END UP BEING THE OVERALL-BEST CHANCE OF RAIN FOR THE MAJORITY OF THE AREA. AS FOR SEVERE WEATHER CHANCES...OBVIOUSLY GIVEN THE RETURN OF TYPICAL SUMMER HEAT/HUMIDITY THERE WILL BE PLENTY OF INSTABILITY AROUND MOST OF THE TIME...BUT ALSO TYPICAL OF SUMMER THE MAJORITY OF THE TIME WILL PROBABLY HAVE NO BETTER THAN MODEST DEEP-LAYER WIND SHEAR AND/OR CAPPING ISSUES. AS A RESULT...THERE IS FAR TOO MUCH UNCERTAINTY TO SAY MUCH ABOUT ANY ORGANIZED SEVERE RISK BEYOND THIS WEEKEND...BUT PER THE STORM PREDICTION CENTER DAY 3 OUTLOOK THERE COULD BE AT LEAST A CONDITIONAL SEVERE THREAT FOR LATE SUNDAY AFTERNOON INTO SUNDAY NIGHT ALONG AND PROBABLY MORE-SO BEHIND THE AFOREMENTIONED COLD FRONT SAGGING INTO NEB ZONES FROM THE NORTH. ALSO...BACKING UP TO RIGHT AWAY SATURDAY MORNING...CANNOT RULE OUT THE POSSIBILITY OF A FEW STRONG STORMS LINGERING IN EASTERN ZONES FROM THE FRIDAY NIGHT ACTIVITY DESCRIBED IN THE SHORT TERM SECTION ABOVE...BUT ODDS ARE THAT ANY LEGITIMATE SEVERE THREAT SHOULD BE OVER BY THEN. GETTING MORE INTO METEOROLOGICAL DETAIL AND TAKING THINGS IN 24-HOUR BLOCKS... SATURDAY DAYTIME-SATURDAY NIGHT...IN THE MID-UPPER LEVEL PICTURE THE SUBTROPICAL RIDGE CENTERED OVER THE SOUTHWESTERN CONUS REMAINS THE DOMINANT INFLUENCE ON CENTRAL PLAINS WEATHER...BUT THE DAYTIME HOURS START OUT WITH THE LINGERING DEPARTURE OF A LOW-AMPLITUDE SHORTWAVE TROUGH FROM FRIDAY NIGHT. AS A RESULT...JUST CANNOT RULE OUT SOME STORMS LINGERING OVER EASTERN ZONES INTO THE MID-MORNING HOURS...AND THUS LARGELY MAINTAINED LOW POPS SATURDAY MORNING FROM THE PREVIOUS FORECAST. BY SATURDAY AFTERNOON INTO ESPECIALLY SATURDAY NIGHT...THE MID-UPPER RIDGE RE-ESTABLISHES ITSELF A BIT AND TURNS THE FLOW MORE NORTHERLY ALOFT OVER THE LOCAL AREA WITH A LACK OF DISCERNIBLE SHORTWAVE TROUGHS. AS A RESULT...DESPITE PLENTY OF INSTABILITY OVER THE AREA...WILL CONTINUE TO SIDE WITH THE CONSENSUS OF MOST MODELS AND KEEP SATURDAY AFTERNOON-NIGHT VOID OF SHOWER/THUNDERSTORM POPS AT THIS TIME...ALTHOUGH COULD AT LEAST SEE SOME ACTIVITY COME VERY CLOSE TO AFFECTING THE CWA. HIGH TEMPS AIMED FROM LOW 90S NORTHEAST TO MID-UPPER 90S SOUTH/SOUTHWEST. SUNDAY DAYTIME-SUNDAY NIGHT...THE ENHANCED HEAT ASPECT AND TO SOME EXTENT THE POSSIBLE STRONG-SEVERE STORM RISK LATE IN THE DAY AND LIKELY MORE SO INTO THE EVENING HAS ALREADY BEEN COVERED ABOVE. IN THE MID-UPPER LEVELS THE RIDGE IS FLATTENED A BIT BY THE PASSAGE OF A PROGRESSIVE SHORTWAVE PASSING BY TO THE NORTH GENERALLY ALONG THE CANADA BORDER. THIS IN TURN ALLOWS A WEAK BUT DECENTLY-DEFINED SURFACE COLD FRONT TO SINK SOUTHWARD INTO AND POSSIBLY ALL THE WAY THROUGH THE CWA DURING THE AFTERNOON/EVENING...POSSIBLY PROMOTING VIGOROUS STORM DEVELOPMENT PRIMARILY WITHIN THE NORTHERN 1/2 OF THE CWA. PLENTY OF UNCERTAINTY HERE THOUGH. MONDAY DAYTIME-MONDAY NIGHT...A BIT STRONGER NORTHWESTERLY FLOW OVERSPREADS THE LOCAL AREA AS THE UPPER JET CORE SINKS FARTHER SOUTHWARD IN RESPONSE TO REINFORCING SHORTWAVE ENERGY DROPS THROUGH THE UPPER MIDWEST. MAINTAINED TOKEN 20 POPS THROUGH THE DAY BUT AS ALREADY MENTIONED THE NIGHT PERIOD FEATURES THE OVERALL-HIGHEST POPS OF THE LONG-TERM PERIOD IN THE 30-40 RANGE AS BOTH THE ECMWF/GFS ARE FAIRLY INSISTENT IN SPARKING POTENTIALLY VIGOROUS AND MORE WIDESPREAD CONVECTION. HIGH TEMPS TEMPER A BIT FROM SUNDAY...GENERALLY AIMED UPPER 80S NORTH-MID 90S SOUTH. TUESDAY DAYTIME-TUESDAY NIGHT...THESE 24 HOURS REMAIN BLANKETED WITH MAINLY TOKEN 20 POPS AS THE CENTRAL PLAINS REMAINS ALONG THE POTENTIALLY SOMEWHAT ACTIVE INTERFACE OF THE NORTHWEST FLOW REGIME DIRECTED ALONG THE INTERFACE BETWEEN THE SOUTHWEST CONUS RIDGE AND A VIGOROUS SOUTHEAST CANADA TROUGH. HIGH TEMPS MID 80S NORTH-LOW 90S SOUTH. WEDNESDAY DAYTIME-WEDNESDAY NIGHT...NOT MUCH CHANGE IN THE OVERALL PATTERN AS NORTHWEST FLOW ALOFT REMAIN IN PLACE. ALTHOUGH THERE ARE SOME INDICATIONS THAT MOST CONVECTION IN THE REGION COULD FOCUS SOUTH AND/OR WEST OF THE CWA...BLANKET COVERAGE OF 20 POPS CONTINUES DUE TO THE UNCERTAINTY. HIGH TEMPS MID 80S NORTH-LOW 90S SOUTH. THURSDAY DAYTIME...ALTHOUGH SLIGHT POPS CONTINUE AREA-WIDE FOR NOW...THERE ARE VERY EARLY INDICATIONS THAT FLOW ALOFT MAY TURN MORE ZONAL AND ALLOW WARMER ALOFT TO PUSH IN FROM THE WEST...POTENTIALLY USHERING IN AT LEAST A BRIEF STRETCH THAT MAY NOT EVEN BE WORTHY OF 20 POPS IN LATER FORECASTS. HIGH TEMPS VERY PRELIMINARILY AIMED MID 80S NORTH-LOW 90S SOUTH...VERY SIMILAR TO TUES-WED. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 624 AM CDT FRI JUL 4 2014 VFR CONDITIONS STILL GOING FOR THIS TAF PERIOD...WITH PRIMARY CONCERNS LYING WITH THUNDERSTORM CHANCES AND WINDS. WILL CONTINUE TO SEE THE POTENTIAL FOR SOME SCATTERED PRECIPITATION THIS MORNING...BUT CONFIDENCE IN IT AFFECTING EITHER TERMINAL IS LOW ENOUGH TO KEEP THE MENTION OUT AT THIS POINT. WILL SEE HOW RADAR TRENDS GO. OTHERWISE...ANOTHER CHANCE FOR THUNDERSTORMS WILL COME THIS EVENING WITH THE ARRIVAL OF ANOTHER UPPER LEVEL DISTURBANCE...AND INSERTED A VCTS MENTION. WONT SEE A NOTABLE CHANCE IN WIND DIRECTION THROUGH THE PERIOD...REMAINING SOUTHERLY...WITH SPEEDS EXPECTED TO PICK UP DURING THE MORNING HOURS...EVENTUALLY REACHING 20 TO 25 MPH WITH GUSTS OVER 30 MPH. SPEEDS SHOULD DIMINISH SOME THIS EVENING/OVERNIGHT. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...ADO LONG TERM...PFANNKUCH AVIATION...ADO
AREA FORECAST DISCUSSION
NWS HASTINGS NE
443 AM CDT FRI JUL 4 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 442 AM CDT FRI JUL 4 2014 SATELLITE AND 00Z UPPER AIR DATA SHOWING THE AREA UNDER NORTHWESTERLY FLOW ALOFT...SET UP BETWEEN A TROUGH CONTINUING TO PUSH TOWARD THE EAST COAST AND A RIDGE AXIS EXTENDING INTO THE ROCKIES FROM HIGH PRESSURE ROUGHLY OVER THE FOUR CORNERS REGION. AT THE SFC...NO NOTABLE CHANGES...THE CWA REMAINS BETWEEN HIGH PRESSURE CENTERED JUST EAST OF THE MISSOURI RIVER...AND A TROUGH OF LOW PRESSURE ALONG THE HIGH PLAINS...KEEPING THOSE SRLY WINDS IN PLACE. STARTING TO SEE A FEW SHOWERS/THUNDERSTORMS DEVELOPING NEAR THE WRN EDGE OF THE CWA...AS A WEAK DISTURBANCE AND INCREASED LIFT VIA A 30- 40ISH KT LLJ EDGES FURTHER EAST. SPC MESO PAGE SHOWING MUCAPE VALUES AROUND 1000 J/KG ALONG THAT WRN EDGE...BUT SHEAR IS FAIRLY LOW. EVEN NOW MODELS STILL VARY WITH THE EVOLUTION OF THIS MORNING...BUT WILL KEEP THE POPS GOING ACROSS THE CWA AND SEE HOW THINGS TREND OVER THE NEXT FEW HOURS. STILL CANT RULE OUT THE POSSIBILITY OF A FEW STRONG STORMS. WILL CONTINUE THE POPS INTO THE MORNING HOURS TODAY...BUT THINKING IS THAT ANY ACTIVITY WILL DIMINISH BY MIDDAY. SOME MODELS HINT AT THE POTENTIAL OF SOME ADDITIONAL ACTIVITY DEVELOPING TO OUR NORTH WITH ANOTHER WEAK DISTURBANCE LATER THIS MORNING INTO THE EARLY AFTERNOON HOURS...BUT AT THIS POINT UNLESS OTHER MODELS START TRENDING THAT WAIT NOT BUYING INTO THAT SOLUTION...AND KEPT THE MIDDAY/AFTERNOON HOURS DRY. BUT IT WILL BE SOMETHING THE DAY SHIFT NEED TO MONITOR...AND UPDATE IF IT DOES INDEED HAPPEN/AFFECT MAINLY NRN PORTIONS OF THE CWA. EXPECTING A BREEZY DAY TODAY AS THE PRESSURE GRADIENT ACROSS THE CWA TIGHTENS AND MIXING POTENTIAL INCREASES...SUSTAINED SPEEDS THIS AFTERNOON OF 20-25 MPH NOT OUT OF THE QUESTION ALONG WITH GUSTS OVER 30 MPH. EXPECTING AT LEAST PARTLY CLOUDY SKIES FOR MOST...WITH HIGHS REACHING INTO THE MID/UPPER 80S. OTHERWISE...THE MAIN FOCUS FOR THE SHORT TERM PERIOD TURNS TO THE WEST...AS THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON ALONG THE HIGH PLAINS ALONG THAT SFC TROUGH AXIS...AS YET ANOTHER UPPER LEVEL DISTURBANCE WORKS ITS WAY OUT OF THE ROCKIES AND ONTO THE PLAINS. THINK THE NAM AND SREF ARE TOO FAST WITH BRINGING THE ACTIVITY EAST...ALREADY AFFECTING THE WRN CWA BY 00Z THIS EVENING. OTHER MODELS...INCLUDING THE RAP/4KM WRF...SHOW THE BETTER CHANCES COMING POST 00Z. TRIMMED BACK THE POPS A BIT FOR THE FIRST FEW HOURS OF THE EVENING...LATEST RAP SHOWING EVEN AT 01Z THE BRUNT OF THE ACTIVITY IS W/NW OF THE CWA. OBVIOUSLY THINGS CAN TREND DIFFERENTLY WITH UPCOMING MODEL RUNS...ANOTHER THING FOR THE DAY SHIFT TO KEEP A CLOSE EYE ON...ESP WITH FOLKS WONDERING WHETHER THEY WILL BE ABLE TO SEE THEIR FIREWORKS SHOWS. WHILE POPS WILL BE ON THE INCREASE DURING THE MID/LATE EVENING HOURS...STILL SOME UNCERTAINTY WITH THE OVERALL COVERAGE...WHICH MAY BE MORE SCATTERED IN NATURE...SO MADE ONLY MINOR TWEAKS TO THE POPS. THAT UNCERTAINTY EVEN CONTINUES INTO THE OVERNIGHT/EARLY MORNING HOURS...THE UPPER LEVEL DISTURBANCE CONTINUES PUSHING EAST BUT MODELS VARY WITH WHERE THE NOSE OF THE LLJ AND BETTER CONVERGENCE WILL END UP...WITH SOME SHOWING ACTIVITY PICKING BACK UP OVER OUR ERN COUNTIES. PLENTY OF DETAINS YET TO IRON OUT...EVEN THIS CLOSE TO THE THUNDERSTORM CHANCES. THINKING AS FAR AS STRONG/SEVERE WEATHER GOES HAS NOT CHANGED MUCH...AS THE SHEAR/INSTABILITY COMBO KEEPS THAT POTENTIAL IN PLACE ACROSS THE ENTIRE CWA. LARGE HAIL/DAMAGING WINDS STILL LOOKING TO THE PRIMARY HAZARDS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 442 AM CDT FRI JUL 4 2014 THE MOST NOTABLE WEATHER STORY OF THIS 6-DAY PERIOD IS A PROLONGED STRETCH OF NEAR-NORMAL TO ABOVE NORMAL SUMMER HEAT...MEANING HIGH TEMPERATURES ON MOST DAYS ACROSS THE MAJORITY OF THE CWA ARE GENERALLY FORECAST TO RANGE SOMEWHERE BETWEEN THE MID-80S AND LOW-90S...WITH PORTIONS OF THE AREA EXCEEDING THIS RANGE ESPECIALLY ON SUNDAY. FOR THOSE WHO ENJOYED THESE PAST FEW BELOW NORMAL DAYS...THIS WEEKEND ESPECIALLY WILL BE A RUDE REMINDER THAT IT IS IN FACT JULY. THE INCREASING TEMPS WILL ALSO BE ACCOMPANIED BY A NOTICEABLE INCREASE IN DEWPOINTS/HUMIDITY AS WELL...WITH DEWS FORECAST TO AVERAGE AT LEAST WELL INTO THE 60S FOR THE MAJORITY OF THE NEXT WEEK...WITH THE CLIMATOLOGICALLY FAVORED NORTHEAST QUADRANT OF THE CWA MOST FAVORED TO SEE DEWPOINTS OCCASIONALLY REACH OR SLIGHTLY EXCEED THE MORE- OPPRESSIVE 70 DEGREE MARK. AS FOR BOTH ACTUAL AIR TEMPERATURE AND HEAT INDEX VALUES...SUNDAY IS CURRENTLY SLATED TO BE THE OVERALL- HOTTEST DAY OF THE SUMMER SO FAR WITHIN THE CWA...AND MADE RELATIVELY LITTLE CHANGE TO PREVIOUS FORECAST WITH ACTUAL TEMPS AIMED FROM THE MID-90S NORTHEAST TO THE UPPER 90S-100 SOUTH/SOUTHWEST. AS FOR HEAT INDEX VALUES SUNDAY AFTERNOON...ALTHOUGH THE LATEST FORECAST KEEPS ALL AREAS AT LEAST SLIGHTLY BELOW HEAT ADVISORY CRITERIA OF 105+ DEGREES...THERE IS A DECENT PERCENTAGE OF THE CWA NOW FORECAST TO OBSERVE VALUES IN THE 100-104 RANGE...SO HAVE KEPT THIS NEAR-ADVISORY HEAT INDEX FORECAST IN THE HAZARDOUS WEATHER OUTLOOK (HWOGID). FORTUNATELY...SUNDAY IS THE ONLY DAY OUT OF THESE 6 FORECAST TO BREACH THE 100+ HEAT INDEX MARK...THANKS TO A WEAK COLD FRONTAL PASSAGE EXPECTED LATE SUNDAY NIGHT INTO MONDAY TEMPERING THE HEAT A BIT...AND ALSO ALLOWING SURFACE BREEZES TO PREVAIL FROM MORE OF AN EAST-SOUTHEAST DIRECTION THROUGH MUCH OF NEXT WEEK INSTEAD OF THE PREVALENT SOUTHERLY DIRECTION EXPECTED THIS WEEKEND. SWITCHING GEARS TO SHOWER/THUNDERSTORM CHANCES...FOR BETTER OR WORSE THESE 6 DAYS SIGNAL A GENERAL RETURN TO THE FORECAST PATTERN OF 1-2 WEEKS AGO...MEANING THAT THERE ARE A MULTITUDE OF FAIRLY LOW 20-30 POPS IN THE FORECAST DURING THE MAJORITY OF 12-HOUR PERIODS...BUT VERY FEW OF THESE PERIODS WILL PROBABLY END UP HAVING WIDESPREAD COVERAGE SO BE SURE TO KEEP THESE MYRIAD CHANCES ESPECIALLY BEYOND THE FIRST FEW DAYS IN PERSPECTIVE. THAT BEING SAID...THE ONLY PERIOD THAT CURRENTLY FEATURES MORE WIDESPREAD COVERAGE OF SOMEWHAT HIGHER 30-40 POPS IS MONDAY NIGHT...SO IF TRENDS HOLD THIS MAY END UP BEING THE OVERALL-BEST CHANCE OF RAIN FOR THE MAJORITY OF THE AREA. AS FOR SEVERE WEATHER CHANCES...OBVIOUSLY GIVEN THE RETURN OF TYPICAL SUMMER HEAT/HUMIDITY THERE WILL BE PLENTY OF INSTABILITY AROUND MOST OF THE TIME...BUT ALSO TYPICAL OF SUMMER THE MAJORITY OF THE TIME WILL PROBABLY HAVE NO BETTER THAN MODEST DEEP-LAYER WIND SHEAR AND/OR CAPPING ISSUES. AS A RESULT...THERE IS FAR TOO MUCH UNCERTAINTY TO SAY MUCH ABOUT ANY ORGANIZED SEVERE RISK BEYOND THIS WEEKEND...BUT PER THE STORM PREDICTION CENTER DAY 3 OUTLOOK THERE COULD BE AT LEAST A CONDITIONAL SEVERE THREAT FOR LATE SUNDAY AFTERNOON INTO SUNDAY NIGHT ALONG AND PROBABLY MORE-SO BEHIND THE AFOREMENTIONED COLD FRONT SAGGING INTO NEB ZONES FROM THE NORTH. ALSO...BACKING UP TO RIGHT AWAY SATURDAY MORNING...CANNOT RULE OUT THE POSSIBILITY OF A FEW STRONG STORMS LINGERING IN EASTERN ZONES FROM THE FRIDAY NIGHT ACTIVITY DESCRIBED IN THE SHORT TERM SECTION ABOVE...BUT ODDS ARE THAT ANY LEGITIMATE SEVERE THREAT SHOULD BE OVER BY THEN. GETTING MORE INTO METEOROLOGICAL DETAIL AND TAKING THINGS IN 24-HOUR BLOCKS... SATURDAY DAYTIME-SATURDAY NIGHT...IN THE MID-UPPER LEVEL PICTURE THE SUBTROPICAL RIDGE CENTERED OVER THE SOUTHWESTERN CONUS REMAINS THE DOMINANT INFLUENCE ON CENTRAL PLAINS WEATHER...BUT THE DAYTIME HOURS START OUT WITH THE LINGERING DEPARTURE OF A LOW-AMPLITUDE SHORTWAVE TROUGH FROM FRIDAY NIGHT. AS A RESULT...JUST CANNOT RULE OUT SOME STORMS LINGERING OVER EASTERN ZONES INTO THE MID-MORNING HOURS...AND THUS LARGELY MAINTAINED LOW POPS SATURDAY MORNING FROM THE PREVIOUS FORECAST. BY SATURDAY AFTERNOON INTO ESPECIALLY SATURDAY NIGHT...THE MID-UPPER RIDGE RE-ESTABLISHES ITSELF A BIT AND TURNS THE FLOW MORE NORTHERLY ALOFT OVER THE LOCAL AREA WITH A LACK OF DISCERNIBLE SHORTWAVE TROUGHS. AS A RESULT...DESPITE PLENTY OF INSTABILITY OVER THE AREA...WILL CONTINUE TO SIDE WITH THE CONSENSUS OF MOST MODELS AND KEEP SATURDAY AFTERNOON-NIGHT VOID OF SHOWER/THUNDERSTORM POPS AT THIS TIME...ALTHOUGH COULD AT LEAST SEE SOME ACTIVITY COME VERY CLOSE TO AFFECTING THE CWA. HIGH TEMPS AIMED FROM LOW 90S NORTHEAST TO MID-UPPER 90S SOUTH/SOUTHWEST. SUNDAY DAYTIME-SUNDAY NIGHT...THE ENHANCED HEAT ASPECT AND TO SOME EXTENT THE POSSIBLE STRONG-SEVERE STORM RISK LATE IN THE DAY AND LIKELY MORE SO INTO THE EVENING HAS ALREADY BEEN COVERED ABOVE. IN THE MID-UPPER LEVELS THE RIDGE IS FLATTENED A BIT BY THE PASSAGE OF A PROGRESSIVE SHORTWAVE PASSING BY TO THE NORTH GENERALLY ALONG THE CANADA BORDER. THIS IN TURN ALLOWS A WEAK BUT DECENTLY-DEFINED SURFACE COLD FRONT TO SINK SOUTHWARD INTO AND POSSIBLY ALL THE WAY THROUGH THE CWA DURING THE AFTERNOON/EVENING...POSSIBLY PROMOTING VIGOROUS STORM DEVELOPMENT PRIMARILY WITHIN THE NORTHERN 1/2 OF THE CWA. PLENTY OF UNCERTAINTY HERE THOUGH. MONDAY DAYTIME-MONDAY NIGHT...A BIT STRONGER NORTHWESTERLY FLOW OVERSPREADS THE LOCAL AREA AS THE UPPER JET CORE SINKS FARTHER SOUTHWARD IN RESPONSE TO REINFORCING SHORTWAVE ENERGY DROPS THROUGH THE UPPER MIDWEST. MAINTAINED TOKEN 20 POPS THROUGH THE DAY BUT AS ALREADY MENTIONED THE NIGHT PERIOD FEATURES THE OVERALL-HIGHEST POPS OF THE LONG-TERM PERIOD IN THE 30-40 RANGE AS BOTH THE ECMWF/GFS ARE FAIRLY INSISTENT IN SPARKING POTENTIALLY VIGOROUS AND MORE WIDESPREAD CONVECTION. HIGH TEMPS TEMPER A BIT FROM SUNDAY...GENERALLY AIMED UPPER 80S NORTH-MID 90S SOUTH. TUESDAY DAYTIME-TUESDAY NIGHT...THESE 24 HOURS REMAIN BLANKETED WITH MAINLY TOKEN 20 POPS AS THE CENTRAL PLAINS REMAINS ALONG THE POTENTIALLY SOMEWHAT ACTIVE INTERFACE OF THE NORTHWEST FLOW REGIME DIRECTED ALONG THE INTERFACE BETWEEN THE SOUTHWEST CONUS RIDGE AND A VIGOROUS SOUTHEAST CANADA TROUGH. HIGH TEMPS MID 80S NORTH-LOW 90S SOUTH. WEDNESDAY DAYTIME-WEDNESDAY NIGHT...NOT MUCH CHANGE IN THE OVERALL PATTERN AS NORTHWEST FLOW ALOFT REMAIN IN PLACE. ALTHOUGH THERE ARE SOME INDICATIONS THAT MOST CONVECTION IN THE REGION COULD FOCUS SOUTH AND/OR WEST OF THE CWA...BLANKET COVERAGE OF 20 POPS CONTINUES DUE TO THE UNCERTAINTY. HIGH TEMPS MID 80S NORTH-LOW 90S SOUTH. THURSDAY DAYTIME...ALTHOUGH SLIGHT POPS CONTINUE AREA-WIDE FOR NOW...THERE ARE VERY EARLY INDICATIONS THAT FLOW ALOFT MAY TURN MORE ZONAL AND ALLOW WARMER ALOFT TO PUSH IN FROM THE WEST...POTENTIALLY USHERING IN AT LEAST A BRIEF STRETCH THAT MAY NOT EVEN BE WORTHY OF 20 POPS IN LATER FORECASTS. HIGH TEMPS VERY PRELIMINARILY AIMED MID 80S NORTH-LOW 90S SOUTH...VERY SIMILAR TO TUES-WED. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1232 AM CDT FRI JUL 4 2014 CURRENTLY HAVE VFR CONDITIONS WITH DRY WEATHER GOING THROUGH THIS TAF PERIOD...BUT CONFIDENCE IN THINGS REMAINING COMPLETELY DRY IS NOT HIGH. MODELS VARY BUT SHOW THE POTENTIAL FOR AT LEAST ISOLATED/SCATTERED PRECIP AROUND AS WE GET CLOSER TO SUNRISE...THEN AGAIN IN THE LATER HOURS OF THE PERIOD. THE ISSUE IS THAT THE OVERALL COVERAGE IS STILL IN QUESTION...SO AT THIS TIME NOT CONFIDENT ENOUGH IN THE TERMINAL AREAS BEING DIRECTLY AFFECTED TO INSERT A MENTION. OTHERWISE...LITTLE CHANGE WITH THE WINDS...EXPECTING SRLY WIND THROUGH THE PERIOD...AND WILL BE GUSTY ESPECIALLY DURING THE DAYTIME HOURS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...ADO LONG TERM...PFANNKUCH AVIATION...ADO
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1243 AM CDT FRI JUL 4 2014 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 328 PM CDT THU JUL 3 2014 MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND TEMPERATURES. LATEST SATELLITE AND OBSERVATIONS SHOW SOME CUMULUS FORMING JUST TO THE WEST OF THE FORECAST AREA THIS AFTERNOON. THE SURFACE HIGH HAS MOVED TO THE EAST AND THE SOUTH WINDS HAVE PICKED UP A LITTLE THIS AFTERNOON. THE PRESSURE GRADIENT CONTINUES TO BE FAIRLY TIGHT DURING THE NIGHT TIME HOURS TONIGHT...SO WINDS SHOULD CONTINUE FROM THE SOUTH DURING THE NIGHT. AN UPPER LEVEL WAVE APPROACHES THE FORECAST AREA TONIGHT. MODELS HAVE DIFFERENT SOLUTIONS FOR THUNDERSTORMS TONIGHT. THE NAM AND FOR THE MOST PART THE ECMWF ARE MOSTLY DRY AND THE HRRR HAS BASICALLY NO THUNDERSTORMS THROUGH THE EVENING HOURS AND INTO THE OVERNIGHT HOURS. THE GFS BRINGS IN THUNDERSTORMS AFTER MIDNIGHT TONIGHT AND SPREADS THE THUNDERSTORMS ACROSS THE AREA THROUGH THE EARLY MORNING HOURS. HAVE MAINTAINED SOME LOW POPS LATE TONIGHT AND FRIDAY MORNING. THE NEXT QUESTION BECOMES WHETHER THERE COULD BE ANY STRONG STORMS WITH THESE. THERE IS AROUND 1500 J/KG OF MUCAPE LATE TONIGHT AND INTO FRIDAY MORNING. THAT COULD BRING IN SOME STORMS THAT COULD BE A LITTLE STRONGER. THE PRESSURE GRADIENT REMAINS TIGHT THROUGH THE DAY ON FRIDAY AS WELL. WILL KEEP SOME BREEZY CONDITIONS DURING THE DAY. THE NEXT UPPER LEVEL WAVE APPROACHES DURING THE AFTERNOON HOURS. FOR NOW WILL CONTINUE WITH THE DRY FORECAST BUT WITH THE WAVE APPROACHING THERE COULD BE A FEW THUNDERSTORMS APPROACHING THE WEST LATE IN THE AFTERNOON. TEMPERATURES WILL CONTINUE ON THE WARMING TREND. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 328 PM CDT THU JUL 3 2014 PATTERN: CONFIDENCE IS HIGH VIA MULTI-AGENCY ENSEMBLE MEANS THAT A LOW TO MODERATELY AMPLITUDE WRN USA RIDGE/ERN USA TROF WILL PREVAIL IN THE LONGWAVES FOR THE NEXT 10 DAYS. HIGH TEMPS WILL BE ABOVE NORMAL SAT-MON...THEN TURNING AT OR A LITTLE BELOW THAN NORMAL TUE- THU. ALOFT: A SUBTROPICAL HIGH WILL BE CENTERED OVER THE DESERT SW AND SRN PLAINS FRI EVE. A SHORTWAVE TROF WILL TOP THE RIDGE AND MOVE ACROSS THE CNTRL PLAINS FRI NIGHT INTO SAT MORNING. IT`S BEST SEEN WITH DYNAMIC TROPOPAUSE TOOLS. BEYOND THAT IT`S ANTICYCLONIC NW FLOW HERE THRU SUN NIGHT...WITH THE POLAR JET CONFINED TO THE US-CAN BORDER. UPSTREAM DEVELOPMENTS OVER THE GULF OF AK WILL RESULT IN RE- AMPLIFICATION OF THE RIDGE OVER WRN CANADA. THIS WILL FORCE HEIGHTS TO FALL OVER THE ERN USA EARLY NEXT WEEK... DRIVING A COOL FRONT INTO THE FCST AREA. NW FLOW WILL CONT MON-THU AND IT IS NEARLY IMPOSSIBLE TO PICK OUT ANY SHORTWAVE TROFS. SURFACE: THE FCST AREA WILL BE IN THE WARM SECTOR UNTIL SUN. THEN SLIGHT AMPLIFICATION WILL SEND A COOL FRONT THRU HERE DURING THE DAY SUN. THIS IS 6-12 HRS FASTER THAN WHEN WE LOOKED AT THIS YESTERDAY ...DEPENDENT UPON WHICH MODEL CHOSEN. THE FRONT WILL BECOME QUASI- STATIONARY OVER KS MON-THU BUT WILL BE MODULATED AND/OR REINFORCED BY TSTM ACTIVITY. HAZARDS: THERE IS SOME POTENTIAL FOR SOME TSTM ACTIVITY FRI NIGHT TO BE SEVERE. FOLLOW THE SPC OUTLOOKS FOR A POSSIBLE UPGRADE TO A SLGT RISK AND THE HWO FROM THIS OFFICE. THERE IS OUTSIDE POTENTIAL FOR A STRONG/MARGINALLY SEVERE TSTM OR TWO SUN INTO SUN NIGHT. OTHER TSTM POTENTIAL EXISTS TUE-THU...BUT NO CONFIDENCE ON POTENCY OR COVERAGE THIS FAR OUT IN A WEAK FORCING REGIME. THE DAILY DETAILS... FRI NIGHT: SCATTERED TSTMS WILL DEVELOP LATE FRI AFTERNOON OVER THE HIGH PLAINS AND INDICATIONS ARE THAT THEY WILL THREATEN AREAS N AND W OF THE TRI-CITIES DURING THE EVENING. SREF PROBABILITIES FOR .01" QPF SUGGEST THIS ACTIVITY WILL DIMINISH OR END AS IT MOVES IN. THIS MAY NOT BE THE END OF THE STORY. IF UPSTREAM STORMS CAN FORM A COMMON COLD POOL AND PROPAGATE E...THEY WILL BE MOVING INTO A MUCH MORE FAVORABLE ENVIRONMENT...WITH MUCAPE AVERAGING 2000 J/KG AND EFFECTIVE SHEAR OF AT LEAST 40 KTS. THE LAST TWO RUNS OF WRF-NMM AND WRF-ARW HI-RES REFLECTIVITY SUGGEST THE IS A POSSIBILITY. WE NEED TO MONITOR THIS TIME PERIOD FOR SEVERE TSTMS. ADDITIONAL TSTMS ARE EXPECTED OVER ERN NEB/KS AFTER MIDNIGHT. THE LLJ WILL REINTENSIFY...BUT LOW PRES THE CANADIAN PRAIRIES /AND POSSIBLY THE TROF MOVING THRU HERE/ WILL FORCE THE LEE TROF E OF ITS CLIMATOLOGICAL POSITION. THE EFFECT WILL BE TO SHOVE THE LLJ CORE E OF THE FCST AREA AFTER MIDNIGHT...REPOSITIONING THE BEST THETA-E ADVECTION AND CONVERGENCE E AS WELL. SAT: ANY LEFTOVER CLOUDS/TSTMS IN THE MORNING DEPART TO THE E. TURNING HOT AS NEARLY THE ENTIRE FCST AREA CLIMBS INTO THE 90S. TSTMS WILL FORM AGAIN OUT TO THE W. DO NOT ENVISION ANY OF THIS ACTIVITY MAKING IT HERE. STEERING FLOW WILL WEAKEN SUBSTANTIALLY AND SHIFT TO N. SUN: COOL FRONTAL PASSAGE. NOT SURE WE ARE HOT ENOUGH IN THE FCST. THE COOL FRONT WILL DRAG A VERY HOT THERMAL RIDGE INTO THE FCST AREA. 100-105F IS ON THE TABLE FOR AREAS ALONG AND S OF HWY 136. IF THIS OCCURS THEN UPR 90S ARE POSSIBLE FOR THE TRI-CITIES. LIGHT WINDS WILL MAKE SUNDAY MISERABLE WITHOUT A/C. DEWPOINTS POOLING ALONG THE FRONT WILL BE 65-71F. THIS WILL PUSH HEAT INDICES TO AROUND 100F OVER S-CNTRL NEB. THE LLJ SAT NIGHT WILL ADVECT AN EML OVER THE FCST AREA. COMBINED WITH SUBSIDENCE THIS WILL IMPOSE A FORMIDABLE CAP. SO TSTM DEVELOPMENT LOOKS IFFY LATE AFTERNOON INTO SUN NIGHT. SUN NIGHT INTO MON MORNING...POSSIBLY A LEFT OVER SHWR/TSTM HERE OR THERE. "IF" A TSTM OR TWO CAN MANAGE TO POP THRU THE CAP...THE POTENTIAL FOR SEVERE LOOKS MARGINAL. INSTABILITY WILL BE SUFFICIENT ...BUT DEEP-LAYER SHEAR WILL BE UNDER 20 KTS. MON: NEAR NORMAL HEAT FOR EARLY JULY...BUT NOTHING EXCESSIVE LIKE SUN. MON NIGHT: FOR NOW QPF FROM 00Z/12Z MODELS ARE FAIRLY WELL-CLUSTERED FOR TSTM/MCS DEVELOPMENT OVER NEB/KS. STAYED TUNED. GIVEN THE STRENGTH OF INSTABILITY AND SHEAR...THIS ACTIVITY WILL HAVE SOME POTENTIAL TO BE SEVERE. WE HAVE LOTS OF TIME FOR DETAILS TO EVOLVE. TUE-THU: SEASONABLE TEMPS AS OF NOW...BUT MODELED TEMPS LOOK TOO WARM FOR THE 500 MB FLOW. ENSEMBLE TEMP ANOMALIES SUGGEST TEMPS WILL TREND COOLER THAN NORMAL. WHILE EVERY LOCATION WILL NOT SEE A TSTM IN THE TUE-THU TIME FRAME ...THE POTENTIAL CANNOT BE RULED OUT THIS FAR IN ADVANCE. HOWEVER... BOTH THE 12Z EC/GEM HAVE A CLEAR SIGNAL THAT A SECONDARY COOL FRONT WILL SWEEP THRU TUE OR TUE NIGHT. IF THIS OCCURS...ENOUGH COOL AIR COULD FORCE THE PREVIOUS FRONT FURTHER S RESULTING IN A DAY OR TWO WHERE WE COULD REMOVE POPS FROM THE FCST. THIS SCENARIO ALSO SUPPORTS THE IDEA OF TRENDING COOLER MID-LATE NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1232 AM CDT FRI JUL 4 2014 CURRENTLY HAVE VFR CONDITIONS WITH DRY WEATHER GOING THROUGH THIS TAF PERIOD...BUT CONFIDENCE IN THINGS REMAINING COMPLETELY DRY IS NOT HIGH. MODELS VARY BUT SHOW THE POTENTIAL FOR AT LEAST ISOLATED/SCATTERED PRECIP AROUND AS WE GET CLOSER TO SUNRISE...THEN AGAIN IN THE LATER HOURS OF THE PERIOD. THE ISSUE IS THAT THE OVERALL COVERAGE IS STILL IN QUESTION...SO AT THIS TIME NOT CONFIDENT ENOUGH IN THE TERMINAL AREAS BEING DIRECTLY AFFECTED TO INSERT A MENTION. OTHERWISE...LITTLE CHANGE WITH THE WINDS...EXPECTING SRLY WIND THROUGH THE PERIOD...AND WILL BE GUSTY ESPECIALLY DURING THE DAYTIME HOURS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...JCB LONG TERM...HALBLAUB AVIATION...ADO
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
926 PM PDT THU JUL 3 2014 .SYNOPSIS... MONSOON MOISTURE WILL PUSH INTO NORTHWEST ARIZONA ON INDEPENDENCE DAY AND SPREAD FARTHER NORTHWEST OVER THE WEEKEND...BRINGING INCREASING CHANCES FOR THUNDERSTORMS AND KNOCKING TEMPERATURES DOWN A FEW MORE DEGREES. THUNDERSTORM CHANCES ARE LIKELY TO CONTINUE AT LEAST THROUGH THE MIDDLE OF NEXT WEEK. && .UPDATE... A ROBUST MESOSCALE CONVECTIVE COMPLEX HAS BEEN MOVING THROUGH CENTRAL ARIZONA OVER THE LAST FEW HOURS. STORM PROPAGATION IN THIS COMPLEX IS TOWARD THE WEST AS STORMS ON THE LEADING EDGE MAKE THEIR WAY TOWARD THE COLORADO RIVER VALLEY. THE PRIMARY FORECAST PROBLEM TONIGHT IS WHETHER THIS ACTIVITY WILL MOVE INTO OUR AREA LATER TONIGHT. MESOSCALE ANALYSIS INDICATES A FAIRLY UNSTABLE ATMOSPHERE AHEAD OF THESE STORMS OVER THE RIVER VALLEY. MLCAPE VALUES OF 100O AS OF 9PM. SO THE ATMOSPHERE IS RIPE. THE OTHER END OF THE EQUATION IS LOW LEVEL FORCING TO KEEP STORMS GOING. THE PHOENIX UPPER AIR SOUNDING FROM 00Z SHOWED A NICE...FAIRLY STRONG...EASTERLY FLOW IN NEAR THE SURFACE WHICH IS MAXIMIZING CONVERGENCE AND KEEPING THE OUTFLOW FROM RACING TOO FAR AHEAD OF CONVECTION AND UNDERCUTTING STORMS. WE WILL NEED TO WATCH CLOSELY OVER THE NEXT FEW HOURS TO SEE IF STORM CONTINUE TO REGENERATE ALONG THE LEADING EDGE OF THE GUST FRONT. THE HRRR MODEL...WHICH HAS A GOOD HANDLE ON THE CURRENT CONDITIONS...SHOWS STORMS POPPING UP IN SOUTHERN MOHAVE AND EXTREME SE SAN BERNARDINO COUNTY BY 2AM. THIS SEEMS REASONABLE GIVEN ALL THE ABOVE. SO WE DECIDED TO INCLUDE A MENTION OF THUNDERSTORMS IN THOSE AREAS. THIS INCLUDES THE CITIES OF LAKE HAVASU...NEEDLES...TOPLOCK AND WIKIUP. STAY TUNED. OF EQUAL CONCERN IS THAT THE CONVECTION IN ARIZONA WILL LAY DOWN A SUFACE BOUNDARY BETWEEN THE RAIN COOLED AIR TO THE EAST AND WARM TEMPERATURES OVER THE COLORADO RIVER VALLEY. THIS COULD BE A FOCUS FOR CONVECTION IN THE EARLY AFTERNOON TOMORROW. AGAIN...WE WILL NEED TO WAIT AND SEE HOW THINGS SET UP WHEN THE CONVECTION ENDS LATER TONIGHT. && .AVIATION...FOR MCCARRAN...EAST TO SOUTHEAST WINDS UNDER 10 KTS WILL SET IN BETWEEN 16-19Z THURSDAY BEFORE GOING BACK TO SOUTH/SOUTHWEST 10-12 KTS WITH GUSTS AROUND 20 KTS THURSDAY AFTERNOON. MONSOON MOISTURE WILL BEGIN TO INCREASE FROM THE SOUTHEAST FRIDAY WITH ISOLATED TO SCATTERED THUNDERSTORMS PUSHING INTO THE PEACH SPRINGS CORRIDOR AND POSSIBLY OVER THE SPRING MOUNTAINS. OUTFLOW FROM THESE STORMS COULD BRING ERRATIC WIND GUSTS TO THE TERMINAL FRIDAY AFTERNOON AND EVENING. CONTINUED MOISTURE INCREASE WILL BRING A SLIGHT CHANCE OF THUNDERSTORMS TO THE TERMINAL BY SATURDAY AFTERNOON. FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST CALIFORNIA...ISOLATED EARLY EVENING THUNDERSTORMS POSSIBLE OVER EASTERN MOHAVE AND NORTHERN LINCOLN COUNTIES THEN MOSTLY CLEAR. MOISTURE WILL BEGIN TO INCREASE FROM THE SOUTHEAST FRIDAY WITH ISOLATED TO SCATTERED THUNDERSTORMS ACROSS MUCH OF MOHAVE COUNTY INTO EASTERN SAN BERNARDINO AND SOUTHERN CLARK COUNTIES. ERRATIC AND GUSTY WINDS NEAR STORMS ALONG WITH CEILING DOWN TO 8-10 KFT. THUNDERSTORM COVERAGE WILL INCREASE BY SATURDAY. GUSTY SOUTH/SOUTHWEST WINDS THROUGH EARLY THIS EVENING WITH MAINLY LIGHT DRAINAGE WINDS OVERNIGHT BECOMING BREEZY FROM THE SOUTH AGAIN LATER FRIDAY WITH GUSTS TO 25 KTS. && .PREV DISCUSSION... /ISSUED 256 PM PDT THU JUL 3 2014/ .SYNOPSIS...MONSOON MOISTURE WILL PUSH INTO NORTHWEST ARIZONA ON INDEPENDENCE DAY AND SPREAD FARTHER NORTHWEST OVER THE WEEKEND...BRINGING INCREASING CHANCES FOR THUNDERSTORMS AND KNOCKING TEMPERATURES DOWN A FEW MORE DEGREES. THUNDERSTORM CHANCES ARE LIKELY TO CONTINUE AT LEAST THROUGH THE MIDDLE OF NEXT WEEK. && .SHORT TERM...MODELS CONTINUE TO INDICATE SOME CHANCE OF THUNDERSTORMS THIS AFTERNOON AND EVENING OVER FAR EASTERN MOHAVE AND NORTHERN LINCOLN COUNTIES WITH ACTIVITY DYING OUT FOR THE OVERNIGHT PERIOD. WITH HIGH PRESSURE SETTING UP NEAR THE FOUR CORNERS REGION FRIDAY AND SATURDAY...MONSOON MOISTURE WILL BE DRAWN UP FROM THE SOUTHEAST INTO OUR AREA. IT STILL LOOKS LIKE THUNDERSTORM CHANCES WILL BE MAINLY LIMITED TO AREAS SOUTH AND EAST OF LAS VEGAS FRIDAY AND FRIDAY NIGHT AND JUST MAYBE OVER THE SPRING MOUNTAINS AND SHEEP RANGE. MOISTURE PUSHES FARTHER NORTH AND WEST EACH DAY SATURDAY AND SUNDAY WITH AT LEAST A SLIGHT CHANCE OF THUNDERSTORMS OVER THE ENTIRE FORECAST AREA BY SUNDAY AFTERNOON. THE BIG QUESTION MARK IN MY MIND IS THE EXISTENCE OR LACK OF A MID/UPPER LEVEL INVERTED TROUGH OR VORT MAX. THE MODELS HAVE BEEN PRETTY CONSISTENT SHOWING SOME SUCH FEATURE MOVING NORTH INTO THE AREA FRIDAY NIGHT INTO SATURDAY...GENERALLY ALONG THE COLORADO RIVER AND NORTHWEST ARIZONA. IT IS DIFFICULT TO FIND THIS FEATURE ON RECENT SATELLITE IMAGERY HOWEVER. IF IT DOES END UP DEVELOPING...IT COULD KEEP THUNDERSTORMS GOING ALL NIGHT FRIDAY NIGHT ACROSS AT LEAST MOHAVE COUNTY AND POSSIBLY OVER EASTERN SAN BERNARDINO COUNTY INTO CLARK COUNTY. HOWEVER...I WENT WITH A MORE TYPICAL DOWNWARD POP TREND FRIDAY NIGHT AS THE NAM12 INDICATES CAPE VALUES LOWERING SIGNIFICANTLY. THE OTHER ISSUE IF THE MORE ACTIVE FRIDAY NIGHT SCENARIO DEVELOPS IS IT COULD ACTUALLY RESULT IN SATURDAY BEING A DOWN DAY FOR CONVECTION DUE TO EXTENSIVE CLOUD COVER LEFT OVER FROM FRIDAY NIGHT`S ACTIVITY AND COOL SURFACE TEMPS. SO IN OTHER WORDS THERE IS STILL PLENTY OF UNCERTAINTY IN THE FORECAST FOR THE WEEKEND. TEMPERATURES WILL CONTINUE TO COOL WITH THIS INCREASE IN MOISTURE AND CLOUD COVER AND THEY COULD EVEN END UP COOLER THAN FORECAST SATURDAY IF THE EXTENSIVE CLOUD COVER DOES DEVELOP AND PERSIST FROM FRIDAY NIGHT`S ACTIVITY. .LONG TERM...MONDAY THROUGH THURSDAY...THE LATEST 12Z ECMWF HAS COME IN EVERY SO SLIGHTLY WETTER FOR THE LONG TERM PERIOD...INCHING CLOSER TO THE GFS. AS A RESULT I HAVE BUMPED UP POPS SLIGHTLY THROUGH THE PERIOD...EXTENDING THEM A BIT FURTHER WEST THAN THE INHERITED FORECAST HAD. FOR BOTH MONDAY AND TUESDAY HAVE GONE AHEAD AND INCLUDED AT LEAST A SLIGHT CHANCE OF PRECIPITATION ACROSS THE ENTIRE FORECAST AREA SINCE I CANNOT RULE SHOWERS OUT AT ANY ONE LOCATION. TOWARDS THE LATTER PART OF THE WEEK THERE COULD BE AN INCREASE IN DRIER SOUTHWESTERLY FLOW WHICH MAY BEGIN TO LIMIT PRECIP CHANCES OVER AT LEAST THE LOWER TERRAIN OF SAN BERNARDINO AND INYO COUNTIES. AS MENTIONED IN THE PREVIOUS DISCUSSION OTHER SENSIBLE WEATHER IMPACTS WILL BE LIMITED TO GUSTY WINDS AND SKY COVER GENERATED BY SHOWERS/THUNDERSTORMS. && .FIRE WEATHER...DRY THUNDERSTORM ACTIVITY IS EXPECTED ALONG THE LEADING EDGE OF A PUSH OF MONSOON MOISTURE SATURDAY. THIS AREA IS EXPECTED TO SET UP ACROSS THE SPRING MOUNTAINS AND SHEEP RANGE AND LINCOLN COUNTY. A FIRE WEATHER WATCH WAS ISSUED. && .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED THROUGH FRIDAY MORNING. THERE IS A CHANCE THAT SPOTTER ACTIVATION WILL BE NEEDED FOR MOHAVE COUNTY FRIDAY AFTERNOON AND FOR MOHAVE...CLARK AND SAN BERNARDINO COUNTIES SATURDAY AND SUNDAY. && && $$ UPDATE: LERICOS PREVIOUS: HARRISON/WOLCOTT FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE: HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1152 PM MDT THU JUL 3 2014 .AVIATION... 06Z TAF CYCLE A CLUSTER OF TS/SHRA WILL CONTINUE TO SPREAD SSWD ACROSS THE SW MTS AND LOWER RIO GRANDE VALLEY THRU THE LATE NIGHT HOURS...WITH AN AREA OF MODERATE TO HEAVY RAIN LINGERING IN THE RIO GRANDE FARTHER N TO THE ABQ AREA. BY SUNRISE THE PCPN SHOULD END. MUCH OF CENTRAL NM SHOULD HAVE STANDING WATER ON THE GROUND...AND THIS MAY RESULT IN PATCHY FOG TOWARD SUNRISE FRIDAY MORNING IF SKIES CAN CLEAR. HOWEVER...MODELS SUGGEST MID AND HIGH LEVEL DEBRIS CLOUDS SHOULD LINGER FROM OVERNIGHT CONVECTION KEEPING THE FOG POSSIBILITY SLIM. WITH THE MONSOON MOISTURE PLUME STREAMING IN AN ARC OVER THE W AND N MTS...SCT TO NMRS STORMS SHOULD FAVOR THOSE AREAS FRI AFTN AND NIGHT. NOT AS CONFIDENT IN VCTS AT KABQ AS FOR LOCATIONS FARTHER N AND W BECAUSE THE MOISTURE PLUME SKIRTS THE SUNPORT. HOWEVER... MODEL STREAMLINES SUGGEST ANY STORMS THAT FIRE ON THE SANDIAS OR MANZANOS SHOULD DRIFT N NWWD TOWARD KABQ. 44 && .PREV DISCUSSION...537 PM MDT THU JUL 3 2014... .UPDATE... BASED ON LATEST RADAR TRENDS...SPC SSEO PRODUCT...THE HI-RES WRF FROM ABQ AND SPC...AS WELL AS THE 23Z LAPS INSTABILITY PARAMS... HAVE UPDATED TO RAISE POPS TO THE LIKELY CATEGORY FOR THE ABQ AND SAF METRO AS WELL AS THE EAST MOUNTAIN COMMUNITIES THIS EVENING. EXPECT ROBUST CONVECTION TO CONTINUE MERGING INTO A CLUSTER AROUND BERNALILLO...SANDOVAL...SANTA FE...AND TORRANCE COUNTIES. THIS CLUSTER IS INDICATED BY MOST GUIDANCE TO SLIDE SLOWLY SOUTH IN THE RIO GRANDE VALLEY WHILE DISSIPATING THROUGH 08Z. GUYER && .PREV DISCUSSION...325 PM MDT THU JUL 3 2014... .SYNOPSIS... CENTER OF UPPER LEVEL DOME OF HIGH PRESSURE WILL REMAIN NEARLY STATIONARY OVER THE FOUR CORNERS REGION THROUGH THE HOLIDAY WEEKEND. ROUNDS OF SCATTERED AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS ARE EXPECTED FRIDAY THROUGH SUNDAY CENTRAL AND WESTERN AREAS WITH ISOLATED ACTIVITY EAST. SHOWER AND THUNDERSTORM ACTIVITY SHIFTS TO MAINLY WESTERN AND NORTHERN NEW MEXICO SUNDAY AND MONDAY AS DRIER AND MORE STABLE AIR ALOFT MOVES INTO THE EASTERN PLAINS. MONSOON MOISTURE WILL BE ON INCREASE ONCE AGAIN TUESDAY THROUGH NEXT WEEK...INCREASING THUNDERSTORM CHANCES FOR MOST OF CENTRAL AND WESTERN NEW MEXICO. && .DISCUSSION... A MUCH HEALTHIER CROP OF THUNDERSTORMS/TOWERING CUMULUS OVER ALL MOUNTAIN RANGES THIS AFTERNOON COMPARED WITH WEDNESDAY. CLASSIC THUNDERHEAD STRUCTURE ALSO APPARENT WITH THE STORMS OVER CENTRAL AND WESTERN NEW MEXICO AS THE FLOW ALOFT IS VERY WEAK. CLOCKWISE STEERING FLOW ALSO QUITE APPARENT AS STORMS OVER NORTHERN NM MOVING/PROPAGATING SOUTHWARD AND STORMS OVER THE SOUTH-CENTRAL AND SOUTHWEST MOUNTAINS DRIFTING EAST AND SOUTHEAST RESPECTIVELY. WITH WEAK STEERING WINDS BEING THE RULE...COLLIDING OUTFLOW BOUNDARIES WILL HAVE TO INITIATE STORMS IN THE BASINS AND VALLEYS THIS EVENING. LOCALLY RUN WRF MODEL MODEL INDICATING THAT A CLUSTER OF STORMS WILL PROPAGATE SOUTHWARD THROUGH NORTH-CENTRAL NEW MEXICO THIS EVENING...QUITE POSSIBLY IMPACTING THE SANTA FE AND ABQ METRO AREAS ALONG WITH EAST MOUNTAIN AREAS. ADDITIONALLY...NAM12 BUFR DATA INDICATING THAT THE MID LEVEL TEMPERATURE INVERSION/CAP OVER THE EASTERN PLAINS WILL BE BROKEN EARLY THIS EVENING WITH A FEW MORE HOURS OF ADDITIONAL HEATING...GETTING EASTERN AREAS INTO THE ACT. SIMILAR SET UP FOR FRIDAY WITH MAIN DIFFERENCE BEING STEERING LEVEL WINDS WILL BE A BIT MORE ELY. TOUGH PART IS GETTING STORMS TO PROPAGATE OFF THE SMALLER MOUNTAINS RANGES SUCH AS THE SANDIAS AND MANZANOS INTO ADJACENT VALLEYS AND BASINS WITH LIGHT AND VARIABLE SFC WINDS. FOURTH OF JULY ACTIVITIES IN THE NORTH VALLEY OF ABQ MAY HAVE TO DEAL WITH STRONG AND GUSTY OUTFLOW WINDS AND PERHAPS A THUNDERSTORM DURING THE EVENING HOURS. NAM12 INDICATING SLIGHTLY LESS ACTIVITY FOR SATURDAY AFTERNOON WITH STEERING FLOW TAKING STORMS SLOWLY WEST AND NORTHWEST. VERY DRY AIRMASS AT 500MB WRAPS AROUND THE UPPER HIGH AND OVER EASTERN AND CENTRAL NM SUNDAY AND MONDAY...LIMITING STORM CHANCES OVER THE EASTERN PLAINS WESTWARD TO THE MIDDLE RG VALLEY. BY TUESDAY...GFS AND ECMWF IN GOOD AGREEMENT THAT A MORE TRADITIONAL UPPER LEVEL PLUME OF MONSOON MOISTURE WILL WORK UP INTO AZ. SUFFICIENT MID LEVEL MOISTURE WILL SEEP INTO WESTERN AND NORTHERN NM FOR AN UPTICK IN CONVECTIVE ACTIVITY TUESDAY THROUGH THURSDAY. MODELS BEGIN TO DISAGREE BEYOND DAY SEVEN AS TO THE LOCATION OF THE UPPER HIGH AND WHETHER OR NOT THE MONSOON PLUME WILL BE CENTERED OVER NM OR AZ. 33 && .FIRE WEATHER... CURRENT SFC ANALYSIS SHOWS THAT GRADUAL DRYING HAS TAKEN PLACE ACROSS WESTERN AND CENTRAL NM WITH THE MORNING MOISTURE MIXING OUT. DESPITE THIS...SHOWERS AND THUNDERSTORMS WILL STILL DEVELOPING IN THIS AREA AND PROVIDE WETTING RAINS...THOUGH A FEW MAY BE ON THE DRIER SIDE. THIS AND CONVECTION ELSEWHERE WILL CONTINUE DEVELOPING THIS EVENING...SLOWLY MOVING SSE ACROSS NORTHERN NM AND WSW ACROSS SW NM. HRRR MODEL INDICATES CONVECTION WILL PERSIST DURING THE OVERNIGHT HOURS...ESPECIALLY ACROSS THE RGV. POTENTIAL FOR CONVECTION TO EXPAND INTO THE EASTERN PLAINS OVERNIGHT AS THE CAP BREAKS PER THE LATEST HRRR AND NAM12 RUNS...SO ADJUSTMENTS WERE MADE TO POP GRIDS. THE UPPER LEVEL HIGH CENTER WILL CONTINUE TO WOBBLE ACROSS THE DESERT SW THROUGH THE WEEKEND...WITH ROUNDS OF SHOWERS AND THUNDERSTORMS EXPECTED EACH DAY. THE THETA-E RIDGE WILL BEGIN TURNING CLOCKWISE AND SHIFT SLIGHTLY NORTH FRIDAY AND SATURDAY...WITH THE HIGHEST POPS OVER THE WESTERN CENTRAL AND NORTHERN HIGH TERRAIN. BY SUNDAY...THE THETA-E RIDGE WILL BECOME LESS ORGANIZED...BUT FAVOR THE GILA MOUNTAINS. DURING THIS PERIOD...THE MOIST SFC AND 700MB LEVEL S TO SE FLOW WILL WEAKEN AND BECOME MORE WESTERLY. THIS WILL RESULT IN GRADUAL DRYING AREAWIDE THROUGH SUNDAY AND OVERALL DOWNTREND IN STORM COVERAGE. MIN RH VALUES WILL LOWER EACH DAY...BUT SHOULD REMAIN ABOVE 15 PERCENT. OVERNIGHT RH RECOVERIES WILL DROP AS WELL...ESPECIALLY FOR VALLEY AREAS. HIGH TEMPERATURES WILL TREND UP SLIGHTLY THROUGH THE PERIOD AS WELL. HIGHS WILL BE NEAR TO SLIGHTLY BELOW NORMAL FRIDAY AND BECOME NEAR TO SLIGHTLY ABOVE NORMAL BY SUNDAY. VENT RATES AND TRANS WINDS WILL BOTTOM OUT FRIDAY BEFORE IMPROVING THROUGH SUNDAY...ESPECIALLY ACROSS NW NM. MODELS BEGIN DIVERGING IN THE SETUP OF THE UPPER LEVEL HIGH THROUGH EARLY NEXT WEEK. USING A BLEND CONCEPT...IT APPEARS A WEAK UPPER LEVEL DISTURBANCE WILL PUSH THE HIGH SLIGHTLY WEST...WITH A WEAK WIND SHIFT AT THE 700 AND 500MB LEVELS. THIS WILL BRING BACK A MORE MOIST SELY TO SLY TO NEW MEXICO. THIS CONCEPTUAL MODEL ALIGNS WITH GFS THETA-E RIDGE POSITIONING. BY MONDAY...THE THETA-E RIDGE BECOME VERTICAL ALONG THE AZ/NM BORDER...AND SLOWLY MOVE E WHILE TURNING CLOCKWISE THROUGH THE WEEK. THIS WILL RESULT IN SLIGHTLY COOLER TEMPS...HIGHER HUMIDITIES...AND MORE WIDESPREAD SHOWER AND THUNDERSTORM COVERAGE TUESDAY THROUGH THE END OF THE WEEK. WILL SEE IF MODELS CONTINUE TO HONE IN ON THIS PATTERN...OR DIVERGE AGAIN. && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
157 AM EDT FRI JUL 4 2014 .SYNOPSIS... THE POSSIBILITY FOR SHOWERS AND THUNDERSTORMS WILL CONTINUE THIS EVENING AS A COLD FRONT APPROACHES FROM THE WEST. THE CHANCE FOR RAIN WILL DIMINISH FRIDAY AFTERNOON BEHIND THE FRONT AS DRIER AND COOLER AIR MOVES INTO THE REGION. COOL AND DRY AIR WILL REMAIN THROUGH THE HOLIDAY WEEKEND. && .NEAR TERM /THROUGH TODAY/... 930 PM EDT UPDATE... ALL WATCHES HAVE EXPIRED THIS EVENING AS THE STORMS THAT DEVELOPED OVER THE CWA THIS AFTERNOON HAVE FOR THE MOST PART EXITED THE AREA. A SFC COLD FRONT IS PUSHING INTO WESTERN NY AND EXPECT TO MOVE THROUGH THE AREA BY 12Z FRIDAY. DECIDED TO KEEP MENTION OF SHOWERS AND THUNDERSTORMS IN THE FORECAST AS A LINE OF WEAK SHOWERS ARE MOVING INTO WESTERN NY. DRIER AND COOLER AIR WILL MOVE INTO THE REGION BEHIND THE FRONT AND THE CHANCE FOR SHOWERS WILL SLOWLY DIMINISH. OTHERWISE... MADE MINOR ADJUSTMENTS TO THE PREVIOUS FORECAST... 115 PM UPDATE... WW 389 (SVR) HAS BEEN ISSUED FOR MUCH OF CNY/NE PA THROUGH 01Z. THE POTENTIAL FOR WIND PRODUCERS IS STILL THERE...WITH ML CAPES BLDG INTO THE 1000-1500 RANGE...AND 0-3 KM SHEAR OF 30-40 KT. A TRANSITION...HOWEVER...MORE TWDS A HEAVY RAIN SCENARIO IS STILL FORESEEN BY LATER THIS AFTN/EARLY IN THE EVE...AS PER PREV DISC BLO. PREV DISC... 1030 AM UPDATE... RELATIVELY MINOR TWEAKS WERE MADE TO THE SKY COVER/POP/WX GRIDS...BASED ON THE LATEST OBSERVATIONAL TRENDS AND HI-RES MODEL GUIDANCE. SAT/RADAR IMAGERY LATE THIS MRNG SHOWS MOSTLY RAIN-FREE CONDS OVER CNY/NE PA...WITH MRNG FOG/STRATUS GIVING WAY TO SUNSHINE. PRIND STILL ARE THAT SHWRS/TSTMS WILL FIRE UP OVER OUR WRN/NRN ZNS EARLY THIS AFTN (16-18Z)...WITH COVERAGE GROWING FARTHER E LATER IN THE DAY (18-20Z AND LATER). OUR LATEST HRRR SIMULATED RADAR OUTPUT SUPPORTS THIS THINKING WELL. AS FAR AS POTENTIAL SVR STORMS GO...WE FEEL THERE WILL BE A FAIRLY NARROW WINDOW OF OPPORTUNITY (MOSTLY 18-21Z)...AS STORMS INITIALLY FORM...AND ARE ABLE TO PLUG INTO DEEP-LYRD SHEAR (0-3 KM VALUES OF 30-40 KT). STG WINDS APPEAR TO BE THE MAIN THREAT IN THIS REGARD. LATE IN THE DAY AND THIS EVE...HEAVY RAIN SHOULD BECOME THE GREATER CONCERN...MOSTLY OVER OUR SERN ZNS (NE PA AND THE WRN CATSKILLS). THE MAIN PLAYERS HERE ARE A STRENGTHENING UPR-LVL JET TO OUR N FROM LK ONT INTO ONT/QUE...A SLOW MOVING FRNTL BNDRY ACRS WRN/CNTRL NY...AND DEEP MOISTURE IN PLACE (WITH INCREASING INPUT FROM ARTHUR BY EARLY EVE). THE LATEST BLENDED TPW/WATER VAPOR IMAGERY SHOWS ARTHUR`S MOISTURE PLUME MERGING INTO THE ALREADY EXISTING BAND OF FAIRLY HI PWAT AIR ALG THE MID-ATL COAST...AS OF LATE THIS MRNG. THE LATEST HI-RES GUIDANCE STILL SUPPORTS LARGER- SCALE MODEL OUTPUT FROM THE LAST COUPLE OF DAYS IN SHOWING BACKING 925-850 MB FLOW...WITH DEEPER TROP MOISTURE ADVECTING INTO ERN PA/NJ/SERN NY BY 22-02Z. MODEL TRAJS FROM THE LATEST GFS/RAP RUNS ALSO SHOW THE LEADING EDGE OF ARTHUR`S INFLUENCE LIKELY INTO ERN PA BY THE ABOVE MENTIONED TIME FRAME. THE ABV DESCRIBED CONFIGURATION OF THE UPR JET CORE...LOW-LVL THETA-E RIDGE AXIS...PWAT...AND A SFC FRNT STILL MATCH THE CONCEPTUAL MODEL FOR A "SWLY JET TYPE PRE" (PREDECESSOR RAIN EVENT) WELL. AS STATED EARLIER...WE THINK THE MAIN FF THREAT IN OUR CWA WILL BE E OF THE I-81 CORRIDOR...BUT SINCE THE WATCH IS PRESENTLY UP AREA-WIDE...AND CONVECTION HAS NOT REALLY SHOWN ITSELF JUST YET...WE`LL LEAVE THE WATCH AREA AS IS FOR THE TIME BEING. OTHERWISE...OUR HIGH TEMP FCST THIS AFTN STILL LOOKS FAIRLY REASONABLE (GENERALLY UPR 70S-MID 80S...WITH SOME UPR 80S IN THE WYO/LACK VLYS OF NE PA). && .SHORT TERM /TONIGHT THROUGH SUNDAY/... 3 AM UPDATE... AN UPPER LEVEL TROF WILL MOVE INTO NY KEEPING TS ARTHUR ON THE COAST. AT THE SFC A LARGE AREA OF HIGH PRESSURE OVER THE MIDWEST WILL PUSH EAST. THIS WILL PUSH SHOWERS OUT OF THE FAR SOUTH AND EAST FRIDAY MORNING. CLOUDS WILL CLEAR LATE FRIDAY INTO FRI NGT AS ARTHUR MOVES INTO NEW ENGLAND AND DRIER AIR MOVES IN FROM THE WEST AHEAD OF THE HIGH. WITH THE CLOUDS AND COLD AIR ALOFT HIGH TEMPS WILL ONLY PEAK MOSTLY IN THE LOW 70S FOR A COLD 4TH. ON SAT THE SFC HIGH WILL BE CENTERED OVER THE MID ATLANTIC BUT EXTEND NORTH INTO ONTARIO PROVIDING THE OUR CWA WITH DRY AND MOSTLY SUNNY WEATHER FRI NGT TO SAT NGT. TEMPERATURES WILL BE COOLER THAN NORMAL SATURDAY BUT WARMER THAN FRIDAY. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... GIVEN THE EXPECTATION OF ACTIVE WEATHER THIS AFTN...MED RNG FSCT INCORPORATED HPC GUIDANCE...WHICH LOOKED VERY GOOD. PTRN WILL FAVOR A BROAD UPR TROF WITH WEAK IMPULSES MOVG THRU...LEADING TO A CHC OF SHRA/TSRA. BEST CHCS APPEAR TO BE WITH A FNTL SYSTEM AFFECTING THE RGN MON NGT/TUE. && .AVIATION /06Z FRIDAY THROUGH TUESDAY/... SECONDARY TROF WILL MOVE THROUGH THE TERMINALS EARLY THIS MORNING. AT 06Z, HIGHLY VARIABLE CONDITIONS ARE OCCURRING ACROSS THE TERMINALS LEADING TO A LOW CONFIDENCE FORECAST. OVERALL LOW MVFR TO CLOSE TO AIRPORT MINS WILL PERSIST OVER THE TERMINALS FOR THE NEXT SEVERAL HOURS WITH GRADUAL IMPROVEMENT TOWARD DAYBREAK AS LOW LEVEL DRYING AND MIXING OCCURS. BY 13Z-14Z, SKIES WILL IMPROVE TO BKN LOW VFR FOR THE DAYTIME PERIOD WITH FAIR WX STRATO CU. THIS EVENING SKIES WILL CLEAR OUT. AT KAVP, MOISTURE FROM ARTHUR WILL PRODUCE OCCASIONAL LOW MVFR SHOWERS THROUGH 10Z. LIGHT WINDS GRADUALLY BECOMING NORTHWEST AROUND 5 KNOTS. BY MID MORNING NORTHWEST WINDS 8-12 KNOTS WITH GUSTS 15-20 KNOTS. LIGHT NORTHWEST OVERNIGHT. OUTLOOK... SATURDAY THROUGH SUN...VFR. MON...VFR. EARLY MORNING IFR FOG POSSIBLE AT KELM. MON NGT/TUE...MVFR PSBL IN SCT TSRA. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...TAC NEAR TERM...KAH/MLJ/TAC SHORT TERM...TAC LONG TERM...JAB/RRM AVIATION...RRM
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1034 PM EDT SAT JUL 5 2014 .SYNOPSIS... DRIER THAN NORMAL CONDITIONS AND FAIR WEATHER CAN BE EXPECTED THROUGH SUNDAY AS CANADIAN HIGH PRESSURE SETTLES OVER THE AREA. THE HIGH WILL MOVE OFFSHORE AND ANCHOR OVER THE WESTERN ATLANTIC ALLOWING HEAT AND HUMIDITY TO RETURN MUCH OF THE UPCOMING WEEK. GRADUALLY DEEPENING LOW PRESSURE ALONG THE PIEDMONT AND SANDHILLS OF THE CAROLINAS...WILL LED TO AN INCREASE IN THUNDERSTORMS THROUGH THE WEEK...MAINLY DURING THE AFTERNOONS AND EVENINGS. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... AS OF 1030 PM SATURDAY...MAINLY THIN CIRRUS IS STREAMING OVERHEAD THIS EVENING...BUT THE INFRARED SATELLITE PRESENTATION IS QUITE A BIT WORSE THAN IT LOOKS FROM THE OFFICE PARKING LOT. THE ONLY LOCATION IN OUR FORECAST AREA WITH LOWER CLOUDS BENEATH THE CIRRUS IS GEORGETOWN WHERE CLOUDS WITH BASES JUST ABOVE 3000 FEET (PRESUMABLY MARITIME CUMULUS) ARE BEING REPORTED ON THE GGE AWOS. THE NEW 00Z NAM CONCURS WITH RECENT HRRR RUNS THAT MARINE SHOWERS MAY ATTEMPT TO SPREAD ONSHORE IN THE GEORGETOWN VICINITY AROUND SUNRISE...SO I HAVE UPPED POPS SLIGHTLY IN THE 11-15Z TIME FRAME THERE. OTHERWISE NO SIGNIFICANT CHANGES ARE NEEDED TO THE FORECAST. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS... HIGH PRESSURE OVER WESTERN VIRGINIA WILL BUILD SOUTHEASTWARD OVERNIGHT...SETTLING ACROSS EASTERN NORTH CAROLINA BEFORE DAYBREAK. TO THE SOUTH A SEEMINGLY OUT-OF-PLACE UPPER LEVEL DISTURBANCE OFF THE GEORGIA COAST IS IGNITING QUITE A BIT OF THUNDERSTORM ACTIVITY FROM SOUTHERN SOUTH CAROLINA TO THE FLORIDA EAST COAST. CONVECTIVE BLOWOFF CLOUDINESS STREAMING NORTHWARD HAS PROVIDED A BIT MORE CLOUD COVER THAN EARLIER ANTICIPATED ACROSS NORTHEASTERN SOUTH CAROLINA INCLUDING GEORGETOWN AND MYRTLE BEACH. WHILE MUCH OF THE LOWER CUMULUS CLOUD COVER THAT DEVELOPED DURING THE HEAT OF THE AFTERNOON WILL DISSIPATE THIS EVENING...THIS HIGHER CONVECTIVE BLOWOFF MAY PERSIST. AS THE WEAK UPPER DISTURBANCE DRIFTS NORTHWARD...ATLANTIC MOISTURE WILL INCREASE ALONG THE BASE OF A SIGNIFICANT SUBSIDENCE INVERSION BETWEEN 775-700 MB...APPROXIMATELY 7500-10500 FEET ABOVE GROUND LEVEL. THIS MAY SPELL INCREASING CLOUD COVER AFTER MIDNIGHT ESPECIALLY ACROSS NORTHEASTERN SOUTH CAROLINA WHERE CONDITIONS MAY TEMPORARILY CLEAR OUT LATER THIS EVENING. WITH FAIRLY STEEP LAPSE RATES BENEATH THE SUBSIDENCE INVERSION IT IS EVEN POSSIBLE NOCTURNAL MARINE CONVECTION DEVELOPING OVER THE SHALLOW INSTABILITY OFFSHORE WILL ADVECT WESTWARD...WITH SHOWER CHANCES DEVELOPING ALONG THE SC COAST SOUTH OF MYRTLE BEACH. LOW TEMPERATURES WILL HAVE A PRONOUNCED NORTH-SOUTH GRADIENT TONIGHT. ACROSS INTERIOR SE NORTH CAROLINA GOOD RADIATIONAL COOLING AND A PREEXISTING COOL/DRY AIRMASS SHOULD ALLOW TEMPERATURES TO FALL INTO 61-65 RANGE...IN PLACES ALMOST 10 DEGREES BELOW NORMAL. ACROSS NE SOUTH CAROLINA MORE CLOUDS AND A HEALTHIER ONSHORE WIND WILL PRECLUDE EFFICIENT RADIATIONAL COOLING WITH LOWS GENERALLY IN THE UPPER 60S TO AROUND 70...WARMEST NEAR THE COAST. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/... AS OF 320 PM SATURDAY...ANOTHER DAY WITH RELATIVELY LOW HUMIDITY WILL PREVAIL SUNDAY BEFORE THE CANADIAN HIGH MIGRATES OFFSHORE SUNDAY NIGHT AND INCREASING SOUTHERLY FLOW BEGINS TO DEVELOP INTO MONDAY. MONDAY WILL BE A WARMER AND MORE HUMID DAY THAN SUNDAY DUE TO VEERING WINDS AND THE USHERING OF A MORE TYPICAL SUMMER TIME AIR-MASS INTO THE CAROLINAS. ON AVERAGE MAXIMUM TEMPS MONDAY LOOKS TO PAN OUT 4-7 DEGREES WARMER THAN SUNDAY. AN UPPER DISTURBANCE IN VICINITY OF A STALLED FRONTAL BOUNDARY OVER GA/SC MAY PRODUCE A FEW SHOWERS OVER OUR VERY SOUTHERN COAST AND COASTAL INTERIOR TO NEAR CAPE FEAR SUNDAY. DRY AIR ALOFT OVER THE REGION WILL SIGNIFICANTLY LIMIT THE EXTENT OF EXPECTED PCPN AND CELL COVERAGE...AND ONLY ISOLATED POP VALUES WILL BE ADVERTISED FOR THE SC ZONES. && .LONG TERM /MONDAY THROUGH SATURDAY/... AS OF 320 PM SATURDAY...ANTICIPATE A FAIRLY DRY AND QUIET START TO THE PERIOD AS A WEAK UPPER LEVEL PATTERN REMAINS IN PLACE FOR TUESDAY INTO EARLY WEDNESDAY...WITH HIGHS ON BOTH DAYS IN THE MID TO UPPER 90S INLAND/LOWER 90S ALONG THE COAST WITH THE AFTERNOON SEA BREEZE...AND OVERNIGHT LOWS IN THE LOW TO MID 70S. PATTERN BEGINS TO CHANGE WEDNESDAY INTO THURSDAY AS AN UPPER LEVEL TROUGH BEGINS TO DIG SOUTH ACROSS THE EASTERN US WITH AN ASSOCIATED COLD FRONT SLOWLY PROGRESSING TOWARDS THE CAROLINAS WITH THE AID OF A HIGH PRESSURE WELL TO THE NORTHWEST . TRICKY PART OF THE FORECAST WILL BE THE PROGRESSION OF THE FRONT AND WHETHER IT STALLS AND FIZZLES WEST OF THE FORECAST AREA...OR IF IT REACHES THE FORECAST AREA AND STALLS. OVERALL...HAVE DECIDED TO KEEP WITH A NON-FRONTAL PASSAGE EVENT...BUT RATHER HAVING IT STALL/FALL JUST SHORT TO OUR WEST. WITH THAT SAID...HAVE SLIGHTLY INCREASED CLOUD COVER/POPS AND KEPT INCREASING CHANCES FOR ISOLATED TO SCATTERED THUNDERSTORMS THROUGH THE REST OF THE WEEK ACROSS THE ENTIRE FORECAST AREA AS MOISTURE INCREASES...WITH PRECIPITABLE WATER VALUES NEARING 2 INCHES OR SLIGHTLY MORE. AS FOR TEMPS WE WILL COOL DOWN SLIGHTLY ON FRIDAY AND SATURDAY WITH HIGHS IN THE UPPER 80S/LOWER 90S AND OVERNIGHT LOWS IN THE LOWER 70S. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... AS OF 00Z...VFR CONDITIONS SHOULD PREVAIL THROUGH THIS TAF PERIOD. SATELLITE IMAGERY THIS EVENING SHOWS SCT/BKN CLOUDS BELOW 10KFT PRIMARILY ACROSS OUR SOUTH CAROLINA TERMINALS. THESE CLOUDS WILL LINGER THROUGH MUCH OF THE NIGHT...WITH MINIMAL AVIATION IMPACTS AS CIGS REMAIN VFR. EAST WINDS MAY BECOME MORE E-NE TOWARD MORNING... GENERALLY 5 KTS OR LESS. AN UPPER DISTURBANCE OFF THE FL/GA COAST IS EXPECTED TO LIFT NORTHWARD ON SUNDAY MORNING...ACCOMPANIED BY INCREASING CLOUD COVER ALONG THE COAST AND A SLIGHT CHANCE OF SHOWERS AT KMYR/KCRE. WILL NOT MENTION ANY PCPN ATTM AS MOST OF THE ACTIVITY IS FORECAST TO REMAIN OFFSHORE...BUT TEMPO -SHRA AT KMYR OR KCRE CANNOT BE RULED OUT ON SUNDAY. EAST WINDS WILL BECOME SOUTHEAST AOB 10 KTS IN THE AFTERNOON AS HIGH PRESSURE MOVES FURTHER OFFSHORE. EXTENDED OUTLOOK...VFR WILL PREVAIL THROUGH THE EXTENDED PERIOD. SLIGHT CHANCE OF SHOWERS/TSTMS WEDNESDAY AND THURSDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1030 PM SATURDAY...THE LIMITED MARINE DATA AVAILABLE CONFIRMS OUR EARLIER FORECAST AND NO SIGNIFICANT CHANGES ARE NEEDED TO WINDS OR SEAS. THE NEW 00Z NAM MODEL PLUS SEVERAL OF THE RECENT RUNS OF THE HRRR MODEL SUGGEST THE POTENTIAL FOR SHOWERS AROUND SUNRISE MAY BE RISING IN THE GEORGETOWN/WINYAH BAY VICINITY AND OFFSHORE. ALSO OF NOTE OUR LOCAL WATERSPOUT THREAT CALCULATOR HAS INCREASED THAT POTENTIAL INTO THE "MODERATE" CATEGORY FOR SUNDAY. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS... 1024 MB HIGH PRESSURE CENTERED OVER WESTERN VIRGINIA IS PRODUCING AN ONSHORE WIND ACROSS MOST OF THE COASTAL SOUTHEAST THIS EVENING. A WEAK AREA OF LOW PRESSURE ASSOCIATED WITH AN ODD MID AND UPPER-LEVEL DISTURBANCE ALONG THE GEORGIA COAST IS HELPING ACCELERATE THE ONSHORE WINDS WITH SUSTAINED SPEEDS AS HIGH AS 20 KNOTS BEING REPORTED NEARSHORE FROM MYRTLE BEACH SOUTHWARD INTO THE CHARLESTON VICINITY. THESE WIND SPEEDS SHOULD GRADUALLY DIMINISH OVERNIGHT...ESPECIALLY ACROSS THE NC WATERS WHERE THE HIGH WILL BUILD DOWN AND SPREAD ITS LESSENED PRESSURE GRADIENT OVERHEAD. A LITTLE TIGHTER PRESSURE GRADIENT SHOULD CONTINUE OVER THE SOUTH CAROLINA WATERS AND THAT IS WHERE MY HIGHEST FORECAST WIND SPEEDS WILL REMAIN. AN EARLIER UPDATE LATE THIS AFTERNOON BROUGHT NEARSHORE SEAS INTO ALIGNMENT WITH THE ONSHORE WINDS...AND NO FURTHER SIGNIFICANT CHANGES ARE NEEDED. THE NEARSHORE WRIGHTSVILLE BEACH BUOY IS REPORTING A 3.4 FT CHOP EVERY 5 SECONDS...WITH NOAA BUOY 41004 40 MILES SOUTHEAST OF CHARLESTON REPORTING A VERY CHOPPY 7 FEET EVERY 5-6 SECONDS. SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 320 PM SATURDAY...ONSHORE ENE-E WINDS SUNDAY MORNING WILL RESULT IN BUMPY 3-4 FOOT SEAS FOR THE MOST PART...BUT AS WINDS GO SE AND S INTO AFTERNOON AND EVENING...SEAS WILL LIKELY DROP ANOTHER FOOT OR SO. SO WHILE NOT IDEAL CONDITIONS...NO ADVISORIES OR EXERCISE CAUTION STATEMENTS WILL BE NEEDED. NO TSTMS EXPECTED ON THE 0-20NM WATERS BUT A FEW SHOWERS MAY DOT AREAS AROUND WINYAH BAY. THE MAJORITY OF WAVE ENERGY WILL BE ARRIVING FROM E AND SE AND A MODERATE CHOP FROM THE S-SW IS EXPECTED MONDAY NIGHT AS WINDS NEAR 20 KT. AN EXERCISE CAUTION STATEMENT IS POSSIBLE MONDAY NIGHT INTO EARLY TUESDAY. LONG TERM /TUESDAY THROUGH THURSDAY/... AS OF 320 PM SATURDAY...PERSISTENT SOUTHWEST FLOW WILL CONTINUE THROUGH THE PERIOD WITH SUSTAINED WINDS OF 10 TO 15 KTS AND GUSTS TO NEAR 20 KTS DURING THE AFTERNOON HOURS EACH AFTERNOON. WITH MAINLY WIND DRIVEN WIND WAVES...TUESDAY AND WEDNESDAY SEAS WILL BE 2 TO 4 FT WITH 5 FTERS POSSIBLE IN THE EXTREME OUTER WATERS...ESPECIALLY IN AMZ-252 AND AMZ-250. INTO THURSDAY...SEAS WILL BEGIN TO SUBSIDE TO 2 TO 3 FT. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...MJC NEAR TERM...TRA SHORT TERM...MJC LONG TERM...SGL AVIATION...BJR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
942 PM CDT SAT JUL 5 2014 .UPDATE... ISSUED AT 942 PM CDT SAT JUL 5 2014 THE FIRST SEVERE THREAT IS NOW EAST OF THE FA. ATTENTION NOW TURNS TO THE WEST WITH STORMS APPROACHING FROM CANADA AND FROM SOUTHERN NORTH DAKOTA. THE HRRR/RAP MAY BE TOO WIDESPREAD WITH COVERAGE IN THEIR FORECASTS...BUT BOTH INDICATE THE POTENTIAL FOR STORMS TO FILL IN BETWEEN THESE TWO SEVERE AREAS...AND INDICATE THAT THESE STORMS HAVE THE POTENTIAL FOR BOWING SEGMENTS (STRONG WIND GUSTS). INSTABILITY REMAINS STRONG...AND DEEP LAYER SHEAR IS INCREASING...ALONG WITH A 40-50 KNOT MID-LEVEL SPEED MAX...AND WITH A STRONG UPPER WAVE (DECENT SYNOPTIC FORCING). SO...THE HI- RES MODELS MAY BE ONTO SOMETHING. THIS LOOKS TO BE A BUSY NIGHT. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 320 PM CDT SAT JUL 5 2014 CHALLENGES INCLUDE THUNDERSTORM CHANCES AND SEVERE POTENTIAL THIS EVENING AND OVERNIGHT. HRRR IS ONCE AGAIN PERFORMING MORE FAVORABLY THAN RAP AS IT RELATES TO CURRENT CONVECTION...SO WILL FOLLOW ITS GUIDANCE FOR THE FIRST 12 TO 18 HOURS AND THEN TRANSITION TO A GLOBAL MODEL ENSEMBLE. SFC TROUGH REFUSES TO BUDGE WITH A DEFINED CLOSED CIRCULATION NEAR THE ND/MN/MB BORDER. WINDS HAVE SHIFTED TO A MORE WESTERLY DIRECTION FROM DEVILS LAKE INTO THE JAMES RIVER VALLEY RESULTING IN A DRIER OVERALL AIR MASS...ALTHOUGH SFC BASED CAPE IS STILL ABOVE 2000 J/KG. BEST CHANCE FOR THUNDERSTORMS LATE THIS AFTERNOON IS ALONG THE INTERNATIONAL BORDER AREA OF NORTHWEST MN IN UNCAPPED MORE MOIST/UNSTABLE ENVIRONMENT NEAREST THE SFC LOW. FORCING IS STILL RATHER WEAK...BUT ONE SEVERE STORM HAS DEVELOPED OVER WINNIPEG AND IS SLOWLY MOVING TO THE EAST. A COUPLE OTHER SMALL CELLS HAVE POPPED UP ALONG THE SFC WIND SHIFT JUST NORTH OF THE BORDER AND IN KITTSON COUNTY. ISOLATED SEVERE IS POSSIBLE GIVEN HIGH INSTABILITY. REST OF THE FORECAST AREA WILL REMAIN DRY THIS EVENING WITH TEMPS GRADUALLY FALLING INTO THE UPPER 60S. FOR LATE TONIGHT INTO EARLY SUNDAY MORNING...ATTENTION TURNS TO THE SHORT-WAVE CURRENTLY ACROSS SOUTHERN ALBERTA. INCREASING SHEAR WILL BEGIN TO INTERACT WITH MUCAPES UP TO 1500 J/KG...POSSIBLY RESULTING IN A NORTH TO SOUTH LINE OF CONVECTION MOVING ACROSS THE DAKOTAS AND INTO NORTHWEST MN. HRRR PLACES THIS LINE ALONG THE VALLEY FLOOR BY 06 UTC. LARGE HAIL AND DAMAGING WIND WILL BE THE PRIMARY THREATS. SCATTERED SHOWERS AND STORMS ARE POSSIBLE MAINLY ACROSS NORTHWEST AND WEST CENTRAL MN ON SUNDAY...BUT TEMPS/DEW POINTS WILL BE LOWER RESULTING IN LESS MUGGY CONDITIONS. WINDS WILL ALSO BE BREEZY AT TIMES FROM THE NORTHWEST WITH GUSTS TO 25 MPH. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 320 PM CDT SAT JUL 5 2014 FLOW ALOFT SHIFTS TO THE NORTHWEST MON/TUES WITH THE NEXT PRIMARY WAVE DROPPING ACROSS THE NORTHERN PLAINS MONDAY/MONDAY NIGHT. SEVERE WEATHER NOT EXPECTED...BUT SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE THROUGH THE DAY ON MONDAY WITH DRYING CONDITIONS FROM WEST TO EAST ON TUESDAY. FOR TUESDAY NIGHT THROUGH SATURDAY...SOME DISAGREEMENT IN HOW DEEP NEXT 500 MB TROUGH WILL BE OVER ONTARIO AND GREAT LAKES REGION. EITHER WAY FCST REGION WILL BE IN NORTHWEST FLOW ALOFT WITH EXITING SHORT WAVE TUESDAY NIGHT THEN GENERAL HIGH PRESSURE FOR WED-EARLY THU. NEXT SIGNIFICANT SHORT WAVE TO IMPACT US LATE THU-FRI. DIDNT STRAY FROM ALL BLEND TEMPS NOR POPS MUCH. OVERALL TEMP REGIME AFTER THIS WEEKEND FAVORS A RETURN TO JUST A FEW DEGREES BELOW AVERAGE FOR HIGH TEMPS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 649 PM CDT SAT JUL 5 2014 THUNDERSTORM CHANCES WILL BE THE MAIN CONCERN THROUGH THIS PERIOD...ESPECIALLY DURING THE OVERNIGHT HOURS. THERE SHOULD BE A BROKEN LINE OF STORMS THAT MOVE FROM WEST TO EAST THROUGH THE REGION. NOT SURE HOW WIDESPREAD THESE STORMS WILL BE...AND KEPT VCTS UNTIL MORE CERTAINTY CAN BE OBTAINED. VFR CONDITIONS OTHERWISE. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...TG SHORT TERM...ROGERS LONG TERM...ROGERS/RIDDLE AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
649 PM CDT SAT JUL 5 2014 .UPDATE... ISSUED AT 649 PM CDT SAT JUL 5 2014 SEE SWOMCD 1278 CONCERNING DETAILS REGARDING THE STORMS CURRENTLY ACROSS NW MINNESOTA. THIS ACTIVITY SHOULD CONTINUE TO MOVE EASTWARD...AND OUT OF THE FA WITHIN THE NEXT FEW HOURS. EYES WILL THEN TURN TO THE WEST...WHERE ACTIVITY IS BEGINNING TO ORGANIZE WESTERN MANITOBA...AND SOUTHWEST NORTH DAKOTA. NOT SURE HOW THESE TWO AREAS WILL PROGRESS THROUGH THE EVENING/OVERNIGHT...BUT THE POTENTIAL IS THERE FOR SOME SORT OF MCS EVENT (WITH EACH EVENT LIKELY REMAINING SEPARATE). ADJUSTED THE TIMING OF FORECASTED POPS...AND WILL LOOK MORE INTO THE DETAILS OF THE OVERNIGHT EVENT WITH THE NEXT UPDATE. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 320 PM CDT SAT JUL 5 2014 CHALLENGES INCLUDE THUNDERSTORM CHANCES AND SEVERE POTENTIAL THIS EVENING AND OVERNIGHT. HRRR IS ONCE AGAIN PERFORMING MORE FAVORABLY THAN RAP AS IT RELATES TO CURRENT CONVECTION...SO WILL FOLLOW ITS GUIDANCE FOR THE FIRST 12 TO 18 HOURS AND THEN TRANSITION TO A GLOBAL MODEL ENSEMBLE. SFC TROUGH REFUSES TO BUDGE WITH A DEFINED CLOSED CIRCULATION NEAR THE ND/MN/MB BORDER. WINDS HAVE SHIFTED TO A MORE WESTERLY DIRECTION FROM DEVILS LAKE INTO THE JAMES RIVER VALLEY RESULTING IN A DRIER OVERALL AIR MASS...ALTHOUGH SFC BASED CAPE IS STILL ABOVE 2000 J/KG. BEST CHANCE FOR THUNDERSTORMS LATE THIS AFTERNOON IS ALONG THE INTERNATIONAL BORDER AREA OF NORTHWEST MN IN UNCAPPED MORE MOIST/UNSTABLE ENVIRONMENT NEAREST THE SFC LOW. FORCING IS STILL RATHER WEAK...BUT ONE SEVERE STORM HAS DEVELOPED OVER WINNIPEG AND IS SLOWLY MOVING TO THE EAST. A COUPLE OTHER SMALL CELLS HAVE POPPED UP ALONG THE SFC WIND SHIFT JUST NORTH OF THE BORDER AND IN KITTSON COUNTY. ISOLATED SEVERE IS POSSIBLE GIVEN HIGH INSTABILITY. REST OF THE FORECAST AREA WILL REMAIN DRY THIS EVENING WITH TEMPS GRADUALLY FALLING INTO THE UPPER 60S. FOR LATE TONIGHT INTO EARLY SUNDAY MORNING...ATTENTION TURNS TO THE SHORT-WAVE CURRENTLY ACROSS SOUTHERN ALBERTA. INCREASING SHEAR WILL BEGIN TO INTERACT WITH MUCAPES UP TO 1500 J/KG...POSSIBLY RESULTING IN A NORTH TO SOUTH LINE OF CONVECTION MOVING ACROSS THE DAKOTAS AND INTO NORTHWEST MN. HRRR PLACES THIS LINE ALONG THE VALLEY FLOOR BY 06 UTC. LARGE HAIL AND DAMAGING WIND WILL BE THE PRIMARY THREATS. SCATTERED SHOWERS AND STORMS ARE POSSIBLE MAINLY ACROSS NORTHWEST AND WEST CENTRAL MN ON SUNDAY...BUT TEMPS/DEW POINTS WILL BE LOWER RESULTING IN LESS MUGGY CONDITIONS. WINDS WILL ALSO BE BREEZY AT TIMES FROM THE NORTHWEST WITH GUSTS TO 25 MPH. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 320 PM CDT SAT JUL 5 2014 FLOW ALOFT SHIFTS TO THE NORTHWEST MON/TUES WITH THE NEXT PRIMARY WAVE DROPPING ACROSS THE NORTHERN PLAINS MONDAY/MONDAY NIGHT. SEVERE WEATHER NOT EXPECTED...BUT SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE THROUGH THE DAY ON MONDAY WITH DRYING CONDITIONS FROM WEST TO EAST ON TUESDAY. FOR TUESDAY NIGHT THROUGH SATURDAY...SOME DISAGREEMENT IN HOW DEEP NEXT 500 MB TROUGH WILL BE OVER ONTARIO AND GREAT LAKES REGION. EITHER WAY FCST REGION WILL BE IN NORTHWEST FLOW ALOFT WITH EXITING SHORT WAVE TUESDAY NIGHT THEN GENERAL HIGH PRESSURE FOR WED-EARLY THU. NEXT SIGNIFICANT SHORT WAVE TO IMPACT US LATE THU-FRI. DIDNT STRAY FROM ALL BLEND TEMPS NOR POPS MUCH. OVERALL TEMP REGIME AFTER THIS WEEKEND FAVORS A RETURN TO JUST A FEW DEGREES BELOW AVERAGE FOR HIGH TEMPS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 649 PM CDT SAT JUL 5 2014 THUNDERSTORM CHANCES WILL BE THE MAIN CONCERN THROUGH THIS PERIOD...ESPECIALLY DURING THE OVERNIGHT HOURS. THERE SHOULD BE A BROKEN LINE OF STORMS THAT MOVE FROM WEST TO EAST THROUGH THE REGION. NOT SURE HOW WIDESPREAD THESE STORMS WILL BE...AND KEPT VCTS UNTIL MORE CERTAINTY CAN BE OBTAINED. VFR CONDITIONS OTHERWISE. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...TG SHORT TERM...ROGERS LONG TERM...ROGERS/RIDDLE AVIATION...TG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
336 PM CDT FRI JUL 4 2014 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 320 PM CDT FRI JUL 4 2014 FRIDAY AFTERNOON...A WARM FRONT EXTENDED FROM LOW PRESSURE ACROSS CENTRAL SASKATCHEWAN SOUTHEAST INTO CENTRAL NORTH DAKOTA. A COLD FRONT WAS MOVING INTO SOUTH CENTRAL SASKATCHEWAN. FOR TONIGHT THE WARM FRONT WILL BE THE FOCUS FOR SCATTERED THUNDERSTORMS ACROSS THE JAMES RIVER VALLEY. EXPECTATIONS ARE LOW FOR CONVECTIVE POTENTIAL ALONG THE COLD FRONT THIS EVENING. HRRR MESO MODEL TRIES TO GET A LINE OF CONVECTION GOING ALONG THE COLD FRONT THIS EVENING BUT DIMINISHES THE CONVECTION LATER THIS EVENING. LOOKS AS THOUGH MORE ORGANIZED SHORTWAVE TROUGH WILL APPROACH SATURDAY AFTERNOON AND THIS WILL FOCUS MORE THUNDERSTORMS ALONG THE FRONTAL BOUNDARY BY THEN. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 320 PM CDT FRI JUL 4 2014 FORECAST HIGHLIGHTS IN THE LONG TERM PERIOD WILL BE THUNDERSTORM CHANCES...ESPECIALLY SATURDAY NIGHT. TEMPERATURES COOL BACK INTO THE 70S AND 80S SUNDAY INTO EARLY NEXT WEEK...WITH ANOTHER WARM UP BY NEXT WEEKS END. VERY WARM AND HUMID CONDITIONS DURING THE DAY SATURDAY LEADS TO SUBSTANTIAL INSTABILITY BY DAYS END INTO THE EVENING. COMPARED TO SATURDAY AFTERNOON...THE SITUATION LOOKS MORE FAVORABLE FOR STORMS SATURDAY EVENING/SATURDAY NIGHT WITH MODELS SUGGESTING 40-50KTS OF 0-6KM SHEAR ALONG A FRONTAL BOUNDARY. WHILE SOME CIN WILL BE PRESENT...STRONG MID/UPPER LEVEL SUPPORT ASSOCIATED WITH AN UPPER JET STREAK AND MID LEVEL IMPULSES MOVING WITHIN THE WEST- NORTHWESTERLY FLOW...MAY BE ENOUGH TO OVERCOME ANY INHIBITION. SPC EXPANDED THE SLIGHT RISK AREA FOR SEVERE WEATHER MORE SOUTH TO INCLUDE MORE OF WEST AND CENTRAL ND TO ACCOMMODATE THOSE AREAS NEAR THE TRACK OF THE MID LEVEL IMPULSES AND FORCING ASSOCIATED WITH THE UPPER JET. SURFACE TROUGH EXITS THE AREA LATE SATURDAY NIGHT. ANOTHER WAVE OFF TO MY NORTHEAST MAY TRIGGER ANOTHER STORM ON SUNDAY AROUND THE TURTLE MOUNTAINS...OTHERWISE LOOKS DRY SUNDAY DAYTIME WITH A BREEZY DRYING-OUT NORTHWEST WIND. ANOTHER EMBEDDED WAVE...TRACKING FARTHER SOUTH ACROSS THE NORTHERN PLAINS...WILL BRING ANOTHER SHOT OF SHOWERS/THUNDERSTORMS SUNDAY NIGHT FOLLOWED BY A MORE ROBUST WAVE SLIDING SOUTHEAST ACROSS SOUTHERN MANITOBA ON MONDAY. WILL KEEP A MENTION OF PRECIPITATION MONDAY FOR THIS LATER FEATURE. UPPER LEVEL RIDGING OFF TO OUR WEST WILL MAINTAIN NORTHWEST UPPER FLOW THROUGH WEDNESDAY. TEMPERATURES WILL BE COOLER WITH HIGHS MAINLY IN THE 70S AND 80S...BUT ALMOST DAILY SHOWER/THUNDERSTORM CHANCES WILL CONTINUE. BOTH THE 12Z GFS/ECMWF BREAK DOWN THE RIDGE BY MID WEEK AS AN UPPER LEVEL LOW PRESSURE SYSTEM MOVES ONTO THE BRITISH COLUMBIA COAST...AND EVENTUALLY ACROSS SOUTHERN CANADA. BOTH MODELS INDICATE A RETURN OF MUCH WARMER TEMPERATURES BY THE END OF THE WORK WEEK AND AND CONTINUED INTERMITTENT THUNDERSTORM CHANCES. WILL HAVE TO WAIT AND SEE HOW THINGS PLAY OUT BEYOND THE EXTEND PERIOD...NEXT WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 320 PM CDT FRI JUL 4 2014 AT 320 PM CDT...A WARM FRONT EXTENDED FROM SURFACE LOW PRESSURE ACROSS SASKATCHEWAN THROUGH CENTRAL NORTH DAKOTA AND ACROSS NORTHERN SOUTH DAKOTA. WARM MOIST FLOW OVER THIS WARM FRONTAL BOUNDARY WILL SUPPORT NUMEROUS THUNDERSTORMS ACROSS EASTERN NORTH DAKOTA THIS AFTERNOON. THIS WILL MORE DIRECTLY IMPACT KJMS THROUGH 00Z. OTHERWISE VFR EXPECTED. && .HYDROLOGY... ISSUED AT 320 PM CDT FRI JUL 4 2014 A SIGNIFICANT AMOUNT OF RUNOFF GENERATED BY RECENT HEAVY RAINFALL CREATED A SUBSTANTIAL INCREASE IN STORAGE AT BOTH ALAMEDA DAM AND LAKE DARLING. RELEASES FROM ALAMEDA DAM INCREASED TO 1060 CFS ON WEDNESDAY. RELEASES FROM LAKE DARLING DAM WILL REMAIN AROUND 2000 CFS. THIS WILL CAUSE MINOR TO MODERATE FLOODING ON THE SOURIS RIVER DOWNSTREAM OF LAKE DARLING THROUGH THE HOLIDAY WEEKEND. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...WAA LONG TERM...NH AVIATION...WAA HYDROLOGY...WAA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
315 PM CDT FRI JUL 4 2014 .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 315 PM CDT FRI JUL 4 2014 CHALLENGES INCLUDE THUNDERSTORM CHANCES THIS AFTERNOON/EVENING AND SEVERE POTENTIAL. ALSO CONCERNED WITH SEVERE CHANCES SATURDAY EVENING INTO EARLY SUNDAY MORNING. RAP HAVING TROUBLE WITH TIMING AND LOCATION OF CURRENT CONVECTION COMPARED TO THE MORE REALISTIC HRRR...SO WILL USE THE LATTER HIGH RESOLUTION GUIDANCE FOR THE NEXT 12 TO 18 HOURS TRANSITIONING TO A GLOBAL ENSEMBLE SATURDAY AND BEYOND. 20 UTC REGIONAL RADAR SHOWS TWO AREAS OF NON-SEVERE CONVECTION. THE FIRST IS A DISORGANIZED CLUSTER MAINLY ACROSS NORTHWEST MN AND THE SECOND IS MUCH SMALLER ALONG THE EASTERN ND/SD BORDER. THIS SECOND AREA OF STORMS HAS THE GREATER POTENTIAL TO BECOME SEVERE GIVEN A WEAKENING CAP IN AN ENVIRONMENT WITH 1500 TO 2000 J/KG OF MLCAPE. HOWEVER...PRIMARY FORCING WITH SHORT-WAVE ALOFT SEEMS TO BE FOCUSED FARTHER NORTH AND MAY BE A LIMITING FACTOR FOR STORM INTENSIFICATION. OVERALL...THESE SHOWERS AND THUNDERSTORMS WILL MOVE TO THE EAST-NORTHEAST THROUGH THE EVENING WITH DRYING CONDITIONS IN THEIR WAKE. THERE STILL COULD BE SOME RE-DEVELOPMENT THIS EVENING...SO WILL KEEP CHANCE POPS GOING EAST OF THE RIVER THROUGH MIDNIGHT. OVERNIGHT WILL BE MAINLY DRY AND WARM WITH TEMPERATURES IN THE UPPER 60S TO NEAR 70 DEGREES. SATURDAY WILL BE VERY WARM AND HUMID WITH TEMPERATURES RISING INTO THE UPPER 80S TO LOWER 90S AND DEW POINTS IN THE UPPER 60S TO LOWER 70S. THIS WILL RESULT IN AN AFTERNOON ENVIRONMENT THAT IS HIGHLY UNSTABLE (SFC CAPE RISING TO 4000 J/KG)...BUT CAPPED BY WARM MID-LEVEL TEMPERATURES. A STRONG SHORT-WAVE WILL MOVE ACROSS THE SOUTHERN CANADIAN PROVINCES SATURDAY EVENING INTO EARLY SUNDAY MORNING PROVIDING THE LIFT NECESSARY FOR THUNDERSTORM DEVELOPMENT. MAIN QUESTION IS IF SFC CONVECTIVE TEMPERATURES WILL BE REACHED AND/OR MID-LEVELS WILL COOL ENOUGH TO INITIATE CONVECTION. WILL FOLLOW SPC THINKING IN THAT CONVECTIVE INITIATION COULD BEGIN ACROSS CENTRAL ND AND EVENTUALLY TRANSITION INTO SOME KIND OF MCS AS THUNDERSTORMS MOVE INTO EASTERN ND/NORTHWEST MN LATE SATURDAY/ EARLY SUNDAY. THIS IDEA IS COVERED WELL IN SPC DAY 2 CONVECTIVE OUTLOOK. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 315 PM CDT FRI JUL 4 2014 SUNDAY WILL BE MOSTLY DRY AND SLIGHTLY COOLER (UPPER 70S TO LOWER 80S) WITH BREEZY NORTHWEST WIND. SHOWER AND THUNDERSTORM CHANCES RETURN FOR MONDAY AS ANOTHER STRONGER SHORT-WAVE MOVES ACROSS THE NORTHERN PLAINS IN NORTHWEST FLOW ALOFT. MONDAY NIGHT-FRIDAY...MODELS IN AGREEMENT INDICATING A WESTERN CONUS RIDGE TO BEGIN THE PERIOD...PLACING THIS REGION IN NORTHWEST FLOW ALOFT. THE RIDGE FLATTENS TOWARD THE END OF THE PERIOD...WITH UPPER FLOW BECOMING MORE ZONAL. INDIVIDUAL SHORTWAVES ARE HARD TO TIME...BUT IT APPEARS TO BE A SITUATION WHERE MOST DAYS WILL HAVE ISOLD-SCATTERED T-STORMS FOR A SHORT DURATION. TEMPERATURES WILL BE NEAR NORMAL VALUES...POSSIBLY ABOVE NORMAL BY THE END OF THE PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 100 PM CDT FRI JUL 4 2014 THE MAIN CONCERN WILL BE THUNDERSTORM CHANCES THIS AFTERNOON AND EVENING. THE TRICKY PART IS TIMING AND COVERAGE...AND USED THE LATEST HI-RES MODEL SOLUTIONS COMBINED WITH THE CURRENT OFFICIAL FORECAST TO COME UP WITH THE MOST PROBABLE OUTCOME. SOUTHERLY WINDS WILL BE GUSTING TO 30-35 MPH THIS AFTERNOON. CALMER WINDS AND VFR CONDITIONS TONIGHT INTO SATURDAY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...ROGERS LONG TERM...ROGERS/TG AVIATION...TG
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
100 PM CDT FRI JUL 4 2014 .UPDATE... ISSUED AT 100 PM CDT FRI JUL 4 2014 CONVECTION HAS INITIATED A FEW HOURS EARLIER THAN PREVIOUSLY EXPECTED WITH A BROKEN LINE OF SHOWERS AND THUNDERSTORMS FROM HALLOCK TO CAVALIER AND THEN SOUTHWEST TOWARDS COOPERSTOWN. HAVE RECEIVED SEVERAL REPORTS OF QUARTER SIZE HAIL ACROSS NORTHEAST ND WITH THE PRIMARY CLUSTER. INTERESTINGLY...THESE STORMS ARE IN AN AREA WITH LITTLE SFC OR MIXED LAYER INSTABILITY AND ONLY 250 TO 750 J/KG OF MUCAPE. SOUTHERLY 850 HPA WINDS UP TO 35 KTS AND APPROACHING SHORT-WAVE ALOFT PROVIDING ENOUGH LIFT FOR CONVECTIVE DEVELOPMENT. EXPECT THESE SHOWERS AND STORMS TO CONTINUE EAST- NORTHEAST THROUGH THE AFTERNOON. WILL KEEP SEVERE WORDING IN THE GRIDS...BUT IT APPEARS AREAL COVERAGE WILL BE LIMITED (ESPECIALLY ACROSS NORTHWEST MN) WITH FORCING OUT RUNNING THE HIGHEST INSTABILITY. SOME RE-DEVELOPMENT IS POSSIBLE FARTHER WEST WITH POCKETS OF ENERGY ALOFT RIDING THE RIDGE. SEVERE POTENTIAL IS GREATER IN THESE AREAS AND WILL MONITOR CLOSELY THROUGH THE AFTERNOON. UPDATE ISSUED AT 1004 AM CDT FRI JUL 4 2014 INTERESTING SET-UP FOR THIS AFTERNOON AND EVENING. QUICK MOVING SHORT-WAVE CURRENTLY ACROSS NORTHEAST MT/NORTHWEST ND WILL MOVE THROUGH BROAD 500 HPA RIDGE AND ACROSS THE FORECAST AREA THIS AFTERNOON AND EVENING. IMMEDIATELY AHEAD OF THIS WAVE...RAP IS SHOWING AN AREA OF 0 TO 6 KM BULK SHEAR FROM 40 TO 45 KTS. BOUNDARY LAYER IS INITIALLY WELL CAPPED THROUGH 18-19 UTC... ERODING THEREAFTER WITH UPWARDS OF 1500 TO 2500 J/KG OF MLCAPE ALONG AND WEST OF THE VALLEY. FURTHER EAST...INSTABILITY IS LESS BUT STILL AROUND 500 J/KG BY MID-AFTERNOON. CONVECTIVE TEMPERATURES ARE IN THE UPPER 80S TO LOW 90S...BUT THERE EXIST STEEP MID-LEVEL LAPSE RATES. 0 TO 3 KM VGP VALUES RISE QUICKLY TO BETWEEN 0.3 AND 0.5 ACROSS NORTHEAST ND INTO NORTHWEST MN. GIVEN ALL THESE FACTORS...SPC DAY ONE SLIGHT RISK AREA LOOKS GOOD. MAIN QUESTION WILL BE IF PRIMARY FORCING ALOFT MOVES THROUGH BEFORE INSTABILITY/SHEAR IS MAXIMIZED AFTER THE CAP ERODES. WILL KEEP SEVERE WORDING IN THE GRIDS AND UPDATE POPS TO REFLECT LATEST TRENDS FROM THE RAP/HRRR...BOTH SHOWING INCREASING SHOWERS AND THUNDERSTORMS (SOME OF WHICH MAY BE STRONG TO SEVERE) FROM WEST TO EAST THIS AFTERNOON AND EVENING MAINLY ACROSS NORTHEAST ND INTO NORTHWEST MN. STORMS SHOULD BE EAST OF THE VALLEY BY LATE EVENING. OTHERWISE...TODAY WILL BE WARM AND BREEZY WITH HIGH TEMPERATURES IN THE UPPER 70S TO LOWER 80S AND A STIFF SOUTHERLY WIND WITH GUSTS UP TO 30 MPH AT TIMES. UPDATE ISSUED AT 650 AM CDT FRI JUL 4 2014 ISOLATED THUNDERSTORM CELLS CONTINUE TO FIRE FROM NERN SD INTO FAR SERN ND AND THE EDGE OF WCNTRL MN. STILL EXPECT THESE CELLS TO INCREASE IN COVERAGE AND LIFT NORTHEASTWARD THROUGH THE MORNING... REACHING INTO THE FARGO-MOORHEAD AREA THROUGH THE FORENOON. ELSE... NO SIG CHANGES TO THE FCST PACKAGE ATTM. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 359 AM CDT FRI JUL 4 2014 ISOLATED THUNDERSTORMS ARE FIRING ACROSS NORTHEAST SD THIS EARLY MORNING ALONG AN ELEVATED BAND OF INSTABILITY...WITH A FEW HUNDRED J/KG OF CAPE SHOWING. RUC AND HRRR HAVE THIS BAND PERSISTING THRU MID MORNING AS IT EXPANDS ACROSS SERN ND INTO WEST CENTRAL MN. THEN THIS BAND CONTINUES TO LIFT INTO NERN ND AND NORTHWEST MN BY MIDDAY...WHERE SURFACE HEATING AND INCREASING LOW LEVEL SHEAR LEAD TO FAIRLY ROBUST LOW LEVELS CAPE /+500 J/KG/ AND LOW LEVEL /0 TO 2 KM LAYER/ VGP EXCEEDING 0.2 UNITS. SPC HAS IDENTIFIED THIS AREA AS A SLIGHT RISK FOR SEVERE WEATHER WITH A 5 PERCENT RISK OF A TORNADO OR TWO. WOULD EXPECT THIS THREAT TO BE MAINLY ALONG AND WEST OF THE RED RIVER FROM MID AFTERNOON ON... SHIFTING INTO NORTHWEST MN FROM LATE AFTERNOON THROUGH SUNSET. A CHASER SHOWER OR TWO IS POSSIBLE DURING THE OVERNIGHT PERIOD. MODELS ARE GENERALLY DRY ON SATURDAY.. WITH MOTTLED CLOUD COVER AND SOMETHING OF A STRENGTHENING CAPPING INVERSION THROUGH THE DAY. AN APPROACHING MID LVL SHORTWV TROF LOOKS TO DISRUPT THAT CAP STARTING INTO NORTHWEST ND BY LATE AFTERNOON... AND PROGRESSING INTO NORTHEAST ND LATE SATURDAY EVENING. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 359 AM CDT FRI JUL 4 2014 SATURDAY NIGHT THROUGH SUNDAY...THERE HAS BEEN...A SIGNAL AMONG MOST MODELS INDICATING THE POTENTIAL FOR A STRONGER SHORTWAVE SATURDAY NIGHT ROUNDING THE RIDGE. THIS WAVE WOULD BE STRONG ENOUGH TO INITIATE CONVECTION...WITH SOME SORT OF MCS SATURDAY NIGHT. DEEP LAYER SHEAR WOULD BE MUCH STRONGER...WITH THIS SYSTEM MOVING INTO A VERY UNSTABLE ENVIRONMENT. SPC CONTINUES TO INDICATE A SLIGHT RISK OF SEVERE STORMS ACROSS THE NORTHERN REGION EARLY ON SUNDAY. MONDAY-THURSDAY...DURING THE EARLY STAGES OF THE WEEK...NORTHWEST FLOW ALOFT WILL AMPLIFY OVER THE NORTHERN PLAINS. MODEL GUIDANCE SUGGESTS A FEW SHORTWAVE TROUGHS MAY AFFECT THE REGION DURING THE MON-TUE TIME FRAME...WITH AT LEAST CHANCES FOR SCT SHOWERS/STORMS. FOR MID TO LATE WEEK...A GRADUAL FLATTENING OF THE FLOW IS EXPECTED. PRECIP CHANCES MAY DECREASE FOR MID-WEEK WITH LITTLE IN THE WAY OF UPPER FORCING...AND SFC HIGH PRESSURE BUILDING INTO THE REGION. GIVEN THE NORTHWEST FLOW...TEMPS SHOULD REMAIN FAIRLY SEASONABLE THROUGH THE MIDDLE OF THE WEEK...BEFORE WARMING BACK UP BY LATE WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 100 PM CDT FRI JUL 4 2014 THE MAIN CONCERN WILL BE THUNDERSTORM CHANCES THIS AFTERNOON AND EVENING. THE TRICKY PART IS TIMING AND COVERAGE...AND USED THE LATEST HI-RES MODEL SOLUTIONS COMBINED WITH THE CURRENT OFFICIAL FORECAST TO COME UP WITH THE MOST PROBABLE OUTCOME. SOUTHERLY WINDS WILL BE GUSTING TO 30-35 MPH THIS AFTERNOON. CALMER WINDS AND VFR CONDITIONS TONIGHT INTO SATURDAY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...ROGERS SHORT TERM...GUST LONG TERM...GUST/MAKOWSKI AVIATION...TG
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1004 AM CDT FRI JUL 4 2014 .UPDATE... ISSUED AT 1004 AM CDT FRI JUL 4 2014 INTERESTING SET-UP FOR THIS AFTERNOON AND EVENING. QUICK MOVING SHORT-WAVE CURRENTLY ACROSS NORTHEAST MT/NORTHWEST ND WILL MOVE THROUGH BROAD 500 HPA RIDGE AND ACROSS THE FORECAST AREA THIS AFTERNOON AND EVENING. IMMEDIATELY AHEAD OF THIS WAVE...RAP IS SHOWING AN AREA OF 0 TO 6 KM BULK SHEAR FROM 40 TO 45 KTS. BOUNDARY LAYER IS INITIALLY WELL CAPPED THROUGH 18-19 UTC... ERODING THEREAFTER WITH UPWARDS OF 1500 TO 2500 J/KG OF MLCAPE ALONG AND WEST OF THE VALLEY. FURTHER EAST...INSTABILITY IS LESS BUT STILL AROUND 500 J/KG BY MID-AFTERNOON. CONVECTIVE TEMPERATURES ARE IN THE UPPER 80S TO LOW 90S...BUT THERE EXIST STEEP MID-LEVEL LAPSE RATES. 0 TO 3 KM VGP VALUES RISE QUICKLY TO BETWEEN 0.3 AND 0.5 ACROSS NORTHEAST ND INTO NORTHWEST MN. GIVEN ALL THESE FACTORS...SPC DAY ONE SLIGHT RISK AREA LOOKS GOOD. MAIN QUESTION WILL BE IF PRIMARY FORCING ALOFT MOVES THROUGH BEFORE INSTABILITY/SHEAR IS MAXIMIZED AFTER THE CAP ERODES. WILL KEEP SEVERE WORDING IN THE GRIDS AND UPDATE POPS TO REFLECT LATEST TRENDS FROM THE RAP/HRRR...BOTH SHOWING INCREASING SHOWERS AND THUNDERSTORMS (SOME OF WHICH MAY BE STRONG TO SEVERE) FROM WEST TO EAST THIS AFTERNOON AND EVENING MAINLY ACROSS NORTHEAST ND INTO NORTHWEST MN. STORMS SHOULD BE EAST OF THE VALLEY BY LATE EVENING. OTHERWISE...TODAY WILL BE WARM AND BREEZY WITH HIGH TEMPERATURES IN THE UPPER 70S TO LOWER 80S AND A STIFF SOUTHERLY WIND WITH GUSTS UP TO 30 MPH AT TIMES. UPDATE ISSUED AT 650 AM CDT FRI JUL 4 2014 ISOLATED THUNDERSTORM CELLS CONTINUE TO FIRE FROM NERN SD INTO FAR SERN ND AND THE EDGE OF WCNTRL MN. STILL EXPECT THESE CELLS TO INCREASE IN COVERAGE AND LIFT NORTHEASTWARD THROUGH THE MORNING... REACHING INTO THE FARGO-MOORHEAD AREA THROUGH THE FORENOON. ELSE... NO SIG CHANGES TO THE FCST PACKAGE ATTM. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 359 AM CDT FRI JUL 4 2014 ISOLATED THUNDERSTORMS ARE FIRING ACROSS NORTHEAST SD THIS EARLY MORNING ALONG AN ELEVATED BAND OF INSTABILITY...WITH A FEW HUNDRED J/KG OF CAPE SHOWING. RUC AND HRRR HAVE THIS BAND PERSISTING THRU MID MORNING AS IT EXPANDS ACROSS SERN ND INTO WEST CENTRAL MN. THEN THIS BAND CONTINUES TO LIFT INTO NERN ND AND NORTHWEST MN BY MIDDAY...WHERE SURFACE HEATING AND INCREASING LOW LEVEL SHEAR LEAD TO FAIRLY ROBUST LOW LEVELS CAPE /+500 J/KG/ AND LOW LEVEL /0 TO 2 KM LAYER/ VGP EXCEEDING 0.2 UNITS. SPC HAS IDENTIFIED THIS AREA AS A SLIGHT RISK FOR SEVERE WEATHER WITH A 5 PERCENT RISK OF A TORNADO OR TWO. WOULD EXPECT THIS THREAT TO BE MAINLY ALONG AND WEST OF THE RED RIVER FROM MID AFTERNOON ON... SHIFTING INTO NORTHWEST MN FROM LATE AFTERNOON THROUGH SUNSET. A CHASER SHOWER OR TWO IS POSSIBLE DURING THE OVERNIGHT PERIOD. MODELS ARE GENERALLY DRY ON SATURDAY.. WITH MOTTLED CLOUD COVER AND SOMETHING OF A STRENGTHENING CAPPING INVERSION THROUGH THE DAY. AN APPROACHING MID LVL SHORTWV TROF LOOKS TO DISRUPT THAT CAP STARTING INTO NORTHWEST ND BY LATE AFTERNOON... AND PROGRESSING INTO NORTHEAST ND LATE SATURDAY EVENING. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 359 AM CDT FRI JUL 4 2014 SATURDAY NIGHT THROUGH SUNDAY...THERE HAS BEEN...A SIGNAL AMONG MOST MODELS INDICATING THE POTENTIAL FOR A STRONGER SHORTWAVE SATURDAY NIGHT ROUNDING THE RIDGE. THIS WAVE WOULD BE STRONG ENOUGH TO INITIATE CONVECTION...WITH SOME SORT OF MCS SATURDAY NIGHT. DEEP LAYER SHEAR WOULD BE MUCH STRONGER...WITH THIS SYSTEM MOVING INTO A VERY UNSTABLE ENVIRONMENT. SPC CONTINUES TO INDICATE A SLIGHT RISK OF SEVERE STORMS ACROSS THE NORTHERN REGION EARLY ON SUNDAY. MONDAY-THURSDAY...DURING THE EARLY STAGES OF THE WEEK...NORTHWEST FLOW ALOFT WILL AMPLIFY OVER THE NORTHERN PLAINS. MODEL GUIDANCE SUGGESTS A FEW SHORTWAVE TROUGHS MAY AFFECT THE REGION DURING THE MON-TUE TIME FRAME...WITH AT LEAST CHANCES FOR SCT SHOWERS/STORMS. FOR MID TO LATE WEEK...A GRADUAL FLATTENING OF THE FLOW IS EXPECTED. PRECIP CHANCES MAY DECREASE FOR MID-WEEK WITH LITTLE IN THE WAY OF UPPER FORCING...AND SFC HIGH PRESSURE BUILDING INTO THE REGION. GIVEN THE NORTHWEST FLOW...TEMPS SHOULD REMAIN FAIRLY SEASONABLE THROUGH THE MIDDLE OF THE WEEK...BEFORE WARMING BACK UP BY LATE WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 650 AM CDT FRI JUL 4 2014 VFR CONDS WITH INCREASING CIRRUS AND MID LEVEL CLOUDS ACROSS THE FA THROOUGH THE DAY. ISOLD TSTMS IN THE SOUTHERN RED RIVER VALLEY THROUGH MIDDAY WILL BECOME SCT AND EXPAND ACROSS NERN ND AND NWRN MN THROUGH THE AFTERNOON. THERE IS A RISK OF SEVERE THUNDERSTORMS FROM MID AFTERNOON INTO THE EARLY EVENING... BECOMING VFR BY NIGHTFALL. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...ROGERS SHORT TERM...GUST LONG TERM...GUST/MAKOWSKI AVIATION...GUST
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
650 AM CDT FRI JUL 4 2014 .UPDATE... ISSUED AT 650 AM CDT FRI JUL 4 2014 ISOLATED THUNDERSTORM CELLS CONTINUE TO FIRE FROM NERN SD INTO FAR SERN ND AND THE EDGE OF WCNTRL MN. STILL EXPECT THESE CELLS TO INCREASE IN COVERAGE AND LIFT NORTHEASTWARD THROUGH THE MORNING... REACHING INTO THE FARGO-MOORHEAD AREA THROUGH THE FORENOON. ELSE... NO SIG CHANGES TO THE FCST PACKAGE ATTM. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 359 AM CDT FRI JUL 4 2014 ISOLATED THUNDERSTORMS ARE FIRING ACROSS NORTHEAST SD THIS EARLY MORNING ALONG AN ELEVATED BAND OF INSTABILITY...WITH A FEW HUNDRED J/KG OF CAPE SHOWING. RUC AND HRRR HAVE THIS BAND PERSISTING THRU MID MORNING AS IT EXPANDS ACROSS SERN ND INTO WEST CENTRAL MN. THEN THIS BAND CONTINUES TO LIFT INTO NERN ND AND NORTHWEST MN BY MIDDAY...WHERE SURFACE HEATING AND INCREASING LOW LEVEL SHEAR LEAD TO FAIRLY ROBUST LOW LEVELS CAPE /+500 J/KG/ AND LOW LEVEL /0 TO 2 KM LAYER/ VGP EXCEEDING 0.2 UNITS. SPC HAS IDENTIFIED THIS AREA AS A SLIGHT RISK FOR SEVERE WEATHER WITH A 5 PERCENT RISK OF A TORNADO OR TWO. WOULD EXPECT THIS THREAT TO BE MAINLY ALONG AND WEST OF THE RED RIVER FROM MID AFTERNOON ON... SHIFTING INTO NORTHWEST MN FROM LATE AFTERNOON THROUGH SUNSET. A CHASER SHOWER OR TWO IS POSSIBLE DURING THE OVERNIGHT PERIOD. MODELS ARE GENERALLY DRY ON SATURDAY.. WITH MOTTLED CLOUD COVER AND SOMETHING OF A STRENGTHENING CAPPING INVERSION THROUGH THE DAY. AN APPROACHING MID LVL SHORTWV TROF LOOKS TO DISRUPT THAT CAP STARTING INTO NORTHWEST ND BY LATE AFTERNOON... AND PROGRESSING INTO NORTHEAST ND LATE SATURDAY EVENING. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 359 AM CDT FRI JUL 4 2014 SATURDAY NIGHT THROUGH SUNDAY...THERE HAS BEEN...A SIGNAL AMONG MOST MODELS INDICATING THE POTENTIAL FOR A STRONGER SHORTWAVE SATURDAY NIGHT ROUNDING THE RIDGE. THIS WAVE WOULD BE STRONG ENOUGH TO INITIATE CONVECTION...WITH SOME SORT OF MCS SATURDAY NIGHT. DEEP LAYER SHEAR WOULD BE MUCH STRONGER...WITH THIS SYSTEM MOVING INTO A VERY UNSTABLE ENVIRONMENT. SPC CONTINUES TO INDICATE A SLIGHT RISK OF SEVERE STORMS ACROSS THE NORTHERN REGION EARLY ON SUNDAY. MONDAY-THURSDAY...DURING THE EARLY STAGES OF THE WEEK...NORTHWEST FLOW ALOFT WILL AMPLIFY OVER THE NORTHERN PLAINS. MODEL GUIDANCE SUGGESTS A FEW SHORTWAVE TROUGHS MAY AFFECT THE REGION DURING THE MON-TUE TIME FRAME...WITH AT LEAST CHANCES FOR SCT SHOWERS/STORMS. FOR MID TO LATE WEEK...A GRADUAL FLATTENING OF THE FLOW IS EXPECTED. PRECIP CHANCES MAY DECREASE FOR MID-WEEK WITH LITTLE IN THE WAY OF UPPER FORCING...AND SFC HIGH PRESSURE BUILDING INTO THE REGION. GIVEN THE NORTHWEST FLOW...TEMPS SHOULD REMAIN FAIRLY SEASONABLE THROUGH THE MIDDLE OF THE WEEK...BEFORE WARMING BACK UP BY LATE WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 650 AM CDT FRI JUL 4 2014 VFR CONDS WITH INCREASING CIRRUS AND MID LEVEL CLOUDS ACROSS THE FA THROOUGH THE DAY. ISOLD TSTMS IN THE SOUTHERN RED RIVER VALLEY THROUGH MIDDAY WILL BECOME SCT AND EXPAND ACROSS NERN ND AND NWRN MN THROUGH THE AFTERNOON. THERE IS A RISK OF SEVERE THUNDERSTORMS FROM MID AFTERNOON INTO THE EARLY EVENING... BECOMING VFR BY NIGHTFALL. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...GUST SHORT TERM...GUST LONG TERM...GUST/MAKOWSKI AVIATION...GUST
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
410 AM CDT FRI JUL 4 2014 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 359 AM CDT FRI JUL 4 2014 ISOLATED THUNDERSTORMS ARE FIRING ACROSS NORTHEAST SD THIS EARLY MORNING ALONG AN ELEVATED BAND OF INSTABILITY...WITH A FEW HUNDRED J/KG OF CAPE SHOWING. RUC AND HRRR HAVE THIS BAND PERSISTING THRU MID MORNING AS IT EXPANDS ACROSS SERN ND INTO WEST CENTRAL MN. THEN THIS BAND CONTINUES TO LIFT INTO NERN ND AND NORTHWEST MN BY MIDDAY...WHERE SURFACE HEATING AND INCREASING LOW LEVEL SHEAR LEAD TO FAIRLY ROBUST LOW LEVELS CAPE /+500 J/KG/ AND LOW LEVEL /0 TO 2 KM LAYER/ VGP EXCEEDING 0.2 UNITS. SPC HAS IDENTIFIED THIS AREA AS A SLIGHT RISK FOR SEVERE WEATHER WITH A 5 PERCENT RISK OF A TORNADO OR TWO. WOULD EXPECT THIS THREAT TO BE MAINLY ALONG AND WEST OF THE RED RIVER FROM MID AFTERNOON ON... SHIFTING INTO NORTHWEST MN FROM LATE AFTERNOON THROUGH SUNSET. A CHASER SHOWER OR TWO IS POSSIBLE DURING THE OVERNIGHT PERIOD. MODELS ARE GENERALLY DRY ON SATURDAY.. WITH MOTTLED CLOUD COVER AND SOMETHING OF A STRENGTHENING CAPPING INVERSION THROUGH THE DAY. AN APPROACHING MID LVL SHORTWV TROF LOOKS TO DISRUPT THAT CAP STARTING INTO NORTHWEST ND BY LATE AFTERNOON... AND PROGRESSING INTO NORTHEAST ND LATE SATURDAY EVENING. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 359 AM CDT FRI JUL 4 2014 SATURDAY NIGHT THROUGH SUNDAY...THERE HAS BEEN...A SIGNAL AMONG MOST MODELS INDICATING THE POTENTIAL FOR A STRONGER SHORTWAVE SATURDAY NIGHT ROUNDING THE RIDGE. THIS WAVE WOULD BE STRONG ENOUGH TO INITIATE CONVECTION...WITH SOME SORT OF MCS SATURDAY NIGHT. DEEP LAYER SHEAR WOULD BE MUCH STRONGER...WITH THIS SYSTEM MOVING INTO A VERY UNSTABLE ENVIRONMENT. SPC CONTINUES TO INDICATE A SLIGHT RISK OF SEVERE STORMS ACROSS THE NORTHERN REGION EARLY ON SUNDAY. MONDAY-THURSDAY...DURING THE EARLY STAGES OF THE WEEK...NORTHWEST FLOW ALOFT WILL AMPLIFY OVER THE NORTHERN PLAINS. MODEL GUIDANCE SUGGESTS A FEW SHORTWAVE TROUGHS MAY AFFECT THE REGION DURING THE MON-TUE TIME FRAME...WITH AT LEAST CHANCES FOR SCT SHOWERS/STORMS. FOR MID TO LATE WEEK...A GRADUAL FLATTENING OF THE FLOW IS EXPECTED. PRECIP CHANCES MAY DECREASE FOR MID-WEEK WITH LITTLE IN THE WAY OF UPPER FORCING...AND SFC HIGH PRESSURE BUILDING INTO THE REGION. GIVEN THE NORTHWEST FLOW...TEMPS SHOULD REMAIN FAIRLY SEASONABLE THROUGH THE MIDDLE OF THE WEEK...BEFORE WARMING BACK UP BY LATE WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1142 PM CDT THU JUL 3 2014 VFR CONDITIONS WILL CONTINUE THROUGHOUT THE PERIOD WITH INCREASING CIRRUS CLOUDS. WINDS WILL BE THE MAIN CONCERN WITH WINDS SHIFTING TO THE SOUTH AND THEN INCREASING BY LATE MORNING WITH GUSTS ABOVE 20 KTS. THERE SHOULD BE SOME SETTLING DOWN OF WINDS AROUND SUNSET. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...GUST LONG TERM...GUST/MAKOWSKI AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1142 PM CDT THU JUL 3 2014 .UPDATE... ISSUED AT 1142 PM CDT THU JUL 3 2014 THE RAP AND HRRR CONTINUE TO SHOW SOME PRECIP ENTERING THE SOUTHERN COUNTIES AROUND 12Z. STILL NOT SURE THAT THERE WILL BE ENOUGH MOISTURE AVAILABLE AT THAT POINT...BUT WITH A FEW BLIPS BEGINNING TO SHOW UP IN SOUTH DAKOTA WILL INCLUDE SOME LOW POPS IN OUR SOUTH FOR LATE TONIGHT/EARLY TOMORROW MORNING. UPDATE ISSUED AT 1000 PM CDT THU JUL 3 2014 A FEW OF THE SHORT RANGE MODELS ARE BREAKING OUT SOME PRECIP IN OUR SOUTHERN COUNTIES NEAR DAWN. THINK THAT IT WILL TAKE A LITTLE BIT TO SATURATE DOWN TO THE SFC...SO KEPT THINGS DRY FOR NOW AND WILL REEVALUATE IN A FEW HOURS. NO MAJOR CHANGES. UPDATE ISSUED AT 640 PM CDT THU JUL 3 2014 NO CHANGES OTHER THAN A FEW MINOR TWEAKS TO CLOUD COVER. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 315 PM CDT THU JUL 3 2014 THIS PERIOD WILL BEGIN QUIET...WITH THUNDERSTORM CHANCES INCREASING LATER ON FRIDAY. 12Z MODELS ARE IN DECENT AGREEMENT...ALTHOUGH CONFIDENCE IS LOW WITH ANY INDIVIDUAL SOLUTION. THERE IS AN UPPER WAVE ACROSS WESTERN IDAHO THAT WILL RIDE OVER THE RIDGE...AND BRING WEAK FORCING TO THE REGION ON FRIDAY. LOW LEVEL SOUTHERLY FLOW WILL SET UP TONIGHT...AND SHOULD ADVECT IN ENOUGH MOISTURE FOR AT LEAST WEAK TO MODERATE INSTABILITY AHEAD OF THE 850MB WIND SHIFT. MOST LIKELY SCENARIO IS THAT STORMS WILL INITIALIZE TO THE WEST...THEN MOVE INTO EASTERN NORTH DAKOTA LATE AFTERNOON/EVENING...SHIFTING EASTWARD OVERNIGHT. COVERAGE SHOULD REMAIN SCATTERED CONSIDERING THE RELATIVELY WEAK SYNOPTIC FORCING. THE MAIN CONCERN WILL BE SEVERE POTENTIAL...AND SPC INDICATES A 5% PROBABILITY ACROSS EASTERN NORTH DAKOTA. DEEP LAYER SHEAR WILL BE BORDERLINE (@30 KNOTS)...AND SEVERE POTENTIAL WILL LIKELY DEPEND ON ACTUAL INSTABILITY. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 315 PM CDT THU JUL 3 2014 SATURDAY-SUNDAY...WARM 900MB-700MB TEMPERATURES WILL ADVECT INTO THE REGION ON SATURDAY...AND WILL LIKELY LEAD TO A STRONG CAP WHICH WILL INHIBIT CONVECTION THROUGH MUCH OF THE DAY. THIS WOULD LEAD TO PLENTY OF SOLAR...WITH VERY WARM MAX TEMPS EXPECTED. MODERATE TO STRONG INSTABILITY WILL DEVELOP AS MOST MODELS INDICATE DEW POINT VALUES INTO THE LOW 70S (WHICH IS POSSIBLE WITH EVAPOTRANSPIRATION BECOMING STRONGER). THERE IS...AND HAS BEEN...A SIGNAL AMONG MOST MODELS INDICATING THE POTENTIAL FOR A STRONGER SHORTWAVE SATURDAY NIGHT ROUNDING THE RIDGE. THIS WAVE WOULD BE STRONG ENOUGH TO INITIATE CONVECTION...WITH SOME SORT OF MCS SATURDAY NIGHT. DEEP LAYER SHEAR WOULD BE MUCH STRONGER...WITH THIS SYSTEM MOVING INTO A VERY UNSTABLE ENVIRONMENT. SPC INDICATES A SLIGHT RISK OF SEVERE STORMS ACROSS THE NORTHERN REGION (ON THE EDGE OF THE CAP) FOR THIS POTENTIAL. ON SUNDAY...THERE SHOULD BE A BREAK IN ACTIVITY...BUT WITH THUNDERSTORMS AGAIN POSSIBLE BY AFTERNOON WITH COLDER UPPER LEVEL TEMPERATURES ADVECTING INTO THE REGION. SUNDAY NIGHT-THURSDAY...FORECAST AREA WILL BE IN NORTHWEST FLOW ALOFT WITH UPPER RIDGE BUILDING INTO SOUTHERN BRITISH COLUMBIA. NET RESULT WILL BE ILL-TIMED SHORT WAVES DIVING SOUTHEAST THROUGH THE AREA. COMBINED WITH SOME INSTABILITY IN THE PERIOD ANY SHORT WAVE COULD CAUSE A FEW SHOWERS/THUNDERSTORMS. THEREFORE KEPT THE 20-30 POPS IN THERE FROM THE BLEND OF THE MODELS AS EACH RUN AND EACH MODEL AS DIFFERENT ONES. OVERALL THOUGH 12Z GFS WETTER THAN 12Z ECMWF/GEM. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1142 PM CDT THU JUL 3 2014 VFR CONDITIONS WILL CONTINUE THROUGHOUT THE PERIOD WITH INCREASING CIRRUS CLOUDS. WINDS WILL BE THE MAIN CONCERN WITH WINDS SHIFTING TO THE SOUTH AND THEN INCREASING BY LATE MORNING WITH GUSTS ABOVE 20 KTS. THERE SHOULD BE SOME SETTLING DOWN OF WINDS AROUND SUNSET. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...JR SHORT TERM...TG LONG TERM...TG/RIDDLE AVIATION...JR
AREA FORECAST DISCUSSION
NWS NORMAN OK
615 PM CDT SAT JUL 5 2014 .AVIATION... MAINLY HIGH CLOUDS EXPECTED THIS EVENING. SOME CONVECTION IN SW KS MAY MAKE A RUN AT NORTHWEST OK... BUT CHANCE OF IMPACTING TAF SITES TOO LOW TO MENTION IN TAF AT THIS TIME. OTHER CONCERN OVERNIGHT IS POSSIBILITY OF ELEVATED SHOWER/THUNDERSTORM DEVELOING IN I-44 CORRIDOR AFTER 06Z. HAVE INTRO SOME MID CLOUDS... BUT HAVE LEFT OUT PRECIP AS AGAIN CHANCES ARE MINIMAL. EXPECT SFC WINDS TO GUST OVER 20KTS DURING THE DAY MOST SITES. 30 && .PREV DISCUSSION... /ISSUED 223 PM CDT SAT JUL 5 2014/ .DISCUSSION... HOT SUMMER WEATHER WILL BE THE MAIN STORY OVER THE NEXT SEVERAL DAYS. THERE WILL BE LOW RAIN CHANCES AT TIMES OVER THE NEXT SEVERAL DAYS...BUT WIDESPREAD RAINS REMAIN UNLIKELY. THERE MAY BE A FEW WEAK SHOWERS AND THUNDERSTORMS THROUGH 9 PM THIS EVENING NEAR AND ALONG AN ENHANCED AREA OF MOISTURE CONVERGENCE NEAR OR JUST EAST OF I-35 WHERE PRECIPITABLE WATER VALUES ARE NEAR 1.5 INCHES AND MLCAPE 2000-3000 J/KG WITH LITTLE TO NO CIN. LATEST HRRR RUNS DEPICTED THIS POSSIBILITY. FOR NOW...DID NOT INCLUDE RAIN IN THE FORECAST AS COVERAGE SHOULD REMAIN UNDER 10 PERCENT. ANY SHOWER OR STORM WOULD BE PULSE IN NATURE...MOVE VERY SLOWLY...AND PERHAPS PRODUCE LOCALIZED GUSTY WINDS AND DOWNPOURS. NOT SURE THIS ACTIVITY WILL EVOLVE DUE TO THE LACK OF LIFT. THIS ACTIVITY WOULD DIMINISH BY SUNSET. A SLIGHTLY HIGHER CHANCE FOR STORMS WILL ARRIVE THIS EVENING ACROSS NORTHWEST OKLAHOMA AS A FEW STORMS DEVELOPING NEAR A WEAK MID/UPPER TROUGH MAY MOVE INTO THESE AREAS AFTER 7 PM. WITHOUT A STRONG TRIGGER FOR LIFT...LOWERED RAIN CHANCES TO 10 PERCENT AND WENT WITH ISOLATED MENTION NORTH OF A CHEYENNE TO BLACKWELL LINE. GUSTY WINDS AND BRIEF DOWNPOURS WOULD BE POSSIBLE WITH THESE POORLY ORGANIZED STORMS AS THEY SLOWLY MOVE SOUTHEAST AND WEAKEN. LATE TONIGHT...THERE IS SOME INDICATION WEAK ISOLATED ELEVATED CONVECTION MAY OCCUR NORTH OF A VERNON TEXAS TO ADA LINE...BUT DID NOT INCLUDE MENTION AS CHANCES REMAIN BELOW 10 PERCENT. SUNDAY AND MONDAY APPEAR TO BE A BIT HOTTER COMPARED TO TODAY WITH A GOOD AMOUNT OF SUN. STORM CHANCES REMAIN TOO LOW TO MENTION. AFTERNOON HEAT INDICES WILL AGAIN BE IN THE 95 TO 105 DEGREE RANGE BOTH DAYS. TUESDAY THROUGH THURSDAY...A WEAK FRONT MAY MAKE IT INTO THE AREA...REACHING NORTHERN OKLAHOMA TUESDAY AFTERNOON BEFORE DISSIPATING OVER THE AREA BY THURSDAY. ADDED LOW RAIN CHANCES...AROUND 20 PERCENT...TUESDAY AFTERNOON NEAR THE FRONT...THEN KEPT 20 TO 40 PERCENT RAIN CHANCES NORTH OF THE RED RIVER TUESDAY NIGHT THROUGH THURSDAY. WIDESPREAD RAINS OR ORGANIZED SEVERE WEATHER ARE NOT EXPECTED...THOUGH A FEW STORMS MAY HAVE GUSTY WINDS AND LOCALLY HEAVY RAINFALL. MORE CLOUDS MAY KEEP TEMPERATURES DOWN SLIGHTLY. FRIDAY INTO NEXT SATURDAY...SEASONABLY HOT AND RAINFREE CONDITIONS ARE FORECAST. MBS && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 72 94 72 96 / 10 10 10 0 HOBART OK 71 97 71 101 / 10 10 10 0 WICHITA FALLS TX 72 97 73 99 / 10 10 10 0 GAGE OK 71 97 71 100 / 10 0 0 0 PONCA CITY OK 74 96 74 99 / 10 10 0 0 DURANT OK 71 94 73 97 / 10 10 0 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 04/17
AREA FORECAST DISCUSSION
NWS NORMAN OK
244 PM CDT FRI JUL 4 2014 .DISCUSSION... A FEW SHOWERS ARE TRYING TO DEVELOP JUST SOUTH OF OUR NORTH TEXAS COUNTIES AND THERE IS SOME SIGNAL IN HIGH-RES MODELS OF SOME LATE AFTERNOON/EVENING SHOWERS IN THE SOUTHWEST SO WILL KEEP LOW POPS INTO THE EARLY EVENING THERE. RAP SHOWS MORE WIDESPREAD QPF SIGNALS... AND ALTHOUGH NOT COMPLETELY OUT OF THE QUESTION... IT APPEARS TO BE OVERDONE. NO SIGNIFICANT CHANGES IN PHILOSOPHY FOR THE FORECAST WITH TEMPERATURES TRENDING WARMER THROUGH EARLY NEXT WEEK THEN SOME LOW POPS NORTH WITH THE APPROACH OF A SURFACE FRONT. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 70 91 71 94 / 10 10 10 10 HOBART OK 68 93 70 97 / 10 10 10 10 WICHITA FALLS TX 71 93 72 96 / 20 10 10 10 GAGE OK 68 93 69 97 / 10 10 20 10 PONCA CITY OK 71 91 73 97 / 10 10 10 10 DURANT OK 70 93 71 95 / 10 10 10 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
624 PM CDT Sat Jul 5 2014 .AVIATION... /00Z TAFS/ VFR expected for the next 24 hours. May see just a few stratus make it into the Northwest Hill Country and JCT area...but clouds should be brief. Left a scattered group of low clouds in for a few hours around sunrise. Otherwise...light southeast winds overnight will pick up to 10 to 15 kts tomorrow more out of the south. No significant aviation weather expected. && .PREV DISCUSSION... /ISSUED 347 PM CDT SAT JUL 5 2014/ SHORT TERM... (Tonight and Sunday) Cumulus development was more extensive over West Central Texas than yesterday. While the 17Z HRRR model reflectivity did indicated isolated shower and thunderstorm activity this afternoon, cumulus at 3 PM had limited vertical extent, and expect dry conditions this evening. Dry conditions continue Sunday as upper ridging holds over the region. Will maintain a persistence forecast, with lows in the lower 70s and highs in the mid 90s. LONG TERM... (Sunday night through next Saturday) Warm and dry conditions will continue across West Central Texas through next week. The center of the upper high will remain over the four corners region through midweek, then flatten and expand east across the Southern Plains through next Saturday. Models still show a weak TUTT moving into extreme south Texas and far northeastern Mexico by Wednesday. This feature will remain nearly stationary across this area through Thursday, then drift slowly west across Northern Mexico by early next weekend. About the only noticeable effect from the TUTT will be an increase in some diurnal cumulus by mid to late week. Temperatures through the extended period will remain at or slightly above seasonal normals for this time of year. && .PRELIMINARY POINT TEMPS/POPS... Abilene 72 94 71 96 72 / 5 5 5 5 5 San Angelo 72 95 69 96 72 / 5 5 5 5 5 Junction 69 94 70 95 70 / 5 5 5 5 5 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 08
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
335 PM CDT FRI JUL 4 2014 .SHORT TERM... ISOLATED TO SCATTERED CONVECTION LOOKS TO PERSIST ANOTHER DAY ACROSS THE FA BUT MOSTLY LIMITED TO THE ROLLING PLAINS THIS AFTERNOON. ENOUGH LOW LEVEL RESIDUAL MOISTURE REMAINS OVER THE ROLLING PLAINS WHICH IS ENOUGH TO PUMP OUT 1500-2000 J/KG OF SURFACE INSTABILITY ALONG WITH MINIMAL TO NO CAPPING. A NORTH- SOUTH AXIS OF WEAKLY HIGHER THETA-E/MIXING RATIO VALUES WAS OBSERVED IN RAP FORECAST FIELDS BUT MAY BE ENOUGH TO SEE SOME CONVECTION. MID LEVEL LAPSE RATES ARE NOT ANYTHING TO WRITE HOME ABOUT AND THERE IS STILL LITTLE TO NO FLOW IN THE ATMOSPHERIC COLUMN. BASES WILL BE FAIRLY HIGHER THIS AFTERNOON WITH TEMPERATURES IN THE ROLLING PLAINS IN THE LOWER 90S. RISING HEIGHTS...LARGE SCALE SUBSIDENCE ALOFT...AND LESS MOISTURE WILL ACT TO QUELL ANY LOW LEVEL EFFECTS FOR THE REST OF THE AREA. A REPEAT OF WIDESPREAD LOW STRATUS APPEARS UNLIKELY FOR SATURDAY MORNING BUT SOME STRATUS MAY TRY TO EDGE IN FROM THE SOUTHEAST BY DAYBREAK. UPPER FLOW WILL TURN MORE NORTHEASTERLY ON SATURDAY GIVING LESS CHANCES OF MOUNTAINOUS CONVECTION REACHING THE FA. HOWEVER A WEAK SHORT WAVE MOVING DOWN FROM THE NORTH MAY BRING SLIGHT CHANCES OF THUNDER TOMORROW EVENING. && .LONG TERM... OTHER THAN THE SLIM POSSIBILITY OF SOME STORMS TOMORROW EVENING... LONG TERM PORTION OF THE FORECAST REMAINS FAIRLY QUIET. BEST POPS APPEAR TO STAY ACROSS THE TX PANHANDLE SO KEPT BARELY SLIGHT CHANCE ACROSS THE NORTHERN PART OF THE FORECAST AREA FOR SATURDAY NIGHT. PAST THAT...RIDGE REMAINS CENTERED WEST TO NORTHWEST OF THE REGION WHICH KEEPS THE FORECAST AREA UNDER NORTH TO NORTHEASTERLY FLOW ALOFT. HEIGHTS REMAIN FAIRLY CONSTANT THROUGH THE FORECAST WHICH MEANS TEMPS SHOULD REMAIN CLOSE TO A FEW DEGREES ABOVE SEASONABLE NORMS FOR THIS TIME OF YEAR. DECENT MOISTURE LEVELS REMAIN ACROSS THE FORECAST AREA FROM THE SURFACE UP TO AROUND 700 HPA WHICH WILL ALSO HELP TO KEEP TEMPERATURES FROM WARMING UP TOO MUCH. JORDAN && .PRELIMINARY POINT TEMPS/POPS... FRIONA 63 89 64 92 67 / 10 10 20 0 10 TULIA 64 89 65 93 68 / 10 10 10 0 10 PLAINVIEW 66 89 66 92 68 / 10 0 10 0 0 LEVELLAND 67 91 67 92 69 / 10 0 10 0 0 LUBBOCK 68 91 67 93 69 / 10 0 10 0 0 DENVER CITY 66 92 67 92 69 / 0 0 10 0 0 BROWNFIELD 67 92 67 92 70 / 10 0 10 0 0 CHILDRESS 69 93 71 96 73 / 20 10 10 0 10 SPUR 69 92 68 95 70 / 20 0 10 0 0 ASPERMONT 71 93 71 97 73 / 20 0 10 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01/14
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
412 AM CDT SUN JUL 6 2014 .DISCUSSION... 320 AM CDT THE MAIN WEATHER CONCERNS THIS MORNING CONTINUE TO CENTER ON THE THREAT FOR STRONG TO SEVERE CONVECTION THIS EVENING. THINGS WILL BECOME NOTICEABLY MORE HUMID ACROSS THE AREA THIS AFTERNOON. ARE VWP AND PROFILER DATA INDICATES THE THE FLOW AT 850 MB IS NEARLY DUE WEST...AND AS A CONSEQUENCE OF THIS...WE ARE NOW BEGINNING TO SET UP SOME DECENT LOW LEVEL THETA E ADVECTION INTO NORTHERN ILLINOIS. REGIONAL RADAR IMAGERY HAS EVEN INDICATED A FEW SHOWERS AND THUNDERSTORMS DEVELOPING ACROSS SOUTHEASTERN IOWA AND INTO MISSOURI EARLY THIS MORNING ALONG THE LEADING EDGE OF THE DEEPER MOISTURE. IT IS POSSIBLE THAT A FEW SHOWERS OR STORMS COULD DEVELOP ACROSS PORTIONS OF THE AREA LATER THIS MORNING/AFTERNOON AS THIS DEEPER MOISTURE BEGINS TO STREAM ACROSS THE AREA. HOWEVER...IT APPEARS THIS WOULD BE A LOW PROBABILITY. CLOUD COVER FROM THUNDERSTORM CLOUD DEBRIS TO THE NORTH SHOULD KEEP SKIES MOSTLY CLOUDY FOR AT LEAST MUCH OF THE MORNING TODAY...WHICH COULD LIMIT INSOLATION...MAKING THE THREAT FOR SURFACE BASED CONVECTION AHEAD OF THE COLD FRONT LESS LIKELY. THEREFORE...IT APPEARS THE HI RES CONVECTIVE ALLOWING MODELS MAY BE OVERDONE WITH THERE SUGGESTION OF ACTIVITY DEVELOPING ACROSS THE AREA DURING THE AFTERNOON AHEAD OF THE MAIN AREA OF ACTIVITY SET TO ARRIVE ACROSS FAR NORTHERN ILLINOIS BY EARLY THIS EVENING. NEVERTHELESS...I HAVE LEFT SLIGHT CHANCE POPS IN ACROSS THE AREA THIS AFTERNOON TO ACCOUNT FOR THE SMALL POTENTIAL OF ISOLATED ACTIVITY FIRING THIS AFTERNOON. THE MAIN FOCUS FOR SEVERE CONVECTION WILL BE ASSOCIATED WITH A COLD FRONT...CURRENTLY SHIFTING SOUTHEASTWARD ACROSS THE DAKOTAS. WITH A VERY WARM AND MOIST AIRMASS SHIFTING OVER THE AREA TODAY AHEAD OF THIS APPROACHING FRONTAL BOUNDARY...AT LEAST A MODERATELY UNSTABLE ATMOSPHERE IS EXPECTED...DESPITE THE POSSIBILITY OF LIMITED INSOLATION TODAY. MLCAPE VALUES IN EXCESS OF 2000 J/KG ARE EXPECTED BY EARLY THIS EVENING...THANKS IN PART TO THE ARRIVAL OF A CORRIDOR OF STEEPER MID LEVEL LAPSE RATES (700-500 MB ~7C/KM)...SAMPLED BY THE 00 UTC RAOBS RUNNING FROM THE PLAINS NORTHEASTWARD ACROSS THE PREFRONTAL AIRMASS OF THE UPPER MIDWEST. IF THE AREA DOES REMAINED CAPPED TO SURFACE BASED ACTIVITY THROUGH THE AFTERNOON...THE MAIN ACTIVITY WILL ARRIVE ACROSS NORTHERN ILLINOIS BY EARLY THIS EVENING. STRONG TO SEVERE CONVECTION IS EXPECTED TO DEVELOP BY LATE AFTERNOON TO OUR NORTH ACROSS SOUTHERN WISCONSIN IN RESPONSE TO THE APPROACHING COLD FRONT...WHICH WILL BE COMPLEMENTED BY MODEST MID/UPPER LEVEL HIGH FALLS...AND HENCE COOLING...ASSOCIATED WITH A DIGGING TROUGH ACROSS THE GREAT LAKES REGION. DEEP LAYER SHEAR WILL NOT BE OVERLY IMPRESSIVE ACROSS THE AREA THIS EVENING. HOWEVER...A MODEST 30 TO 35 KT WEST-NORTHWESTERLY FLOW IS EXPECTED TO SET UP AT 500 MB ACROSS THE AREA AND THIS SHOULD YIELD AT LEAST 30 TO 35 KT OF DEEP LAYER SHEAR...CAPABLE OF SUPPORTING SUPER CELLS AND BOWING LINE SEGMENTS ACROSS NORTHERN ILLINOIS. IT APPEARS THE THREAT FOR BOWING LINE SEGMENTS WITH STRONG WIND GUSTS WILL BECOME THE PRIMARY MODE OF CONVECTION DURING THE EVENING AS STORMS WILL LIKELY ORGANIZE A COLD POOL. THERE ALSO APPEARS TO BE A LOW END THREAT OF A TORNADO EARLY THIS EVENING...MAINLY ACROSS FAR NORTHERN ILLINOIS AND INTO WISCONSIN. LOW LEVEL WIND SHEAR OF 20-25 KT IS EXPECTED AS THE FLOW AROUND 2-3000 FT BEGINS TO INCREASE THIS EVENING. THE COMBINATION OF THIS AND LOW LCL HEIGHTS AND LOW LEVEL CAPE COULD SUPPORT AT LEAST A SHORT WINDOW OF A TORNADO THREAT. THE LINE OF CONVECTION SHOULD BEGIN TO AFFECT MOST AREAS NORTH OF INTERSTATE 80 BETWEEN 00 AND 04 UTC. GIVEN THE HIGH MOISTURE CONTENT OF THE ATMOSPHERE...THE STORMS COULD PRODUCE A BRIEF PERIOD OF VERY HEAVY RAINFALL...BUT THE FAIRLY PROGRESSIVE NATURE OF THE STORMS SHOULD LIMIT THE OVERALL TOTALS IN ANY GIVEN AREA. THE CONVECTIVE ACTIVITY MAY BEGIN TO WEAKEN LATER IN THE EVENING AND OVERNIGHT AS IT PROGRESSES TOWARDS MY SOUTHERN CWA. SO THE EXTENT OF THE SEVERE THREAT ACROSS MY SOUTHERN COUNTIES IS A BIT UNCERTAIN. IT APPEARS THINGS WILL QUIET DOWN FOR A SHORT PERIOD ON MONDAY...AS WE AWAIT THE NEXT SYSTEM. HOWEVER...CONDITIONS WILL LIKELY REMAIN VERY WARM AND HUMID ACROSS THE AREA...IN SPITE OF THE PASSAGE OF THE SURFACE BOUNDARY. UNDER WESTERLY SURFACE FLOW...TEMPERATURES COULD AGAIN END UP IN THE UPPER 80S TO NEAR 90. THERE IS A SMALL CHANCE OF AN AFTERNOON LAKE BREEZE ALONG THE IMMEDIATE SHORES OF INDIANA AND COOK COUNTY...GIVEN THE WEAKENING SYNOPTIC WIND FIELD IN THE AFTERNOON. THIS COULD RESULT IN SOME SLIGHTLY COOLER CONDITIONS THERE IN THE AFTERNOON. THE NEXT DECENT THREAT FOR CONVECTION APPEARS TO BE LATE MONDAY NIGHT INTO TUESDAY. ANOTHER...MORE ENERGETIC UPPER LEVEL DISTURBANCE IS FORECAST DIG SOUTHEASTWARD ACROSS THE UPPER MIDWEST AND GREAT LAKES REGION BY TUESDAY. THIS COULD SET UP ANOTHER PERIOD OF STRONG CONVECTION AND HEAVY RAINFALL MONDAY NIGHT INTO TUESDAY GIVEN SOME STRONG DEEP LAYER SHEER. HOWEVER...AT THIS TIME IT APPEARS THE BIGGER SEVERE THREAT MAY REMAIN TO THE SOUTH AND WEST OF THE AREA...IN CLOSER PROXIMITY TO THE REMNANT FRONTAL BOUNDARY AND BETTER INSTABILITY EXPECTED TO RESIDE ACROSS THE CENTRAL PORTION OF THE STATE. THE THREAT FOR VERY HEAVY RAINFALL WITH THIS SYSTEM WILL NEED TO BE WATCHED THOUGH...AS THE POTENTIAL EXISTS FOR A PERIOD OF VERY HEAVY RAINFALL...ESPECIALLY ACROSS CENTRAL ILLINOIS INTO TUESDAY MORNING. ONCE THIS SYSTEM PASSES THE AREA ON TUESDAY...IT STILL APPEARS THINGS WILL QUIET DOWN FOR A COUPLE DAYS FOR THE SECOND HALF OF THE WEEK. COOL HIGH PRESSURE SHOULD SHIFT SOUTHEASTWARD ACROSS THE AREA...SETTING UP A FEW COOLER AND DRIER DAYS. KJB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 09Z... * CHANCE OF SHRA/TSRA LATE MORNING AND AFTERNOON SUNDAY * PERIOD OF SHRA/TSRA LIKELY LATER SUNDAY EVENING IZZI //DISCUSSION...UPDATED 06Z... VFR OVC WILL OVERSPREAD THE AREA OVERNIGHT AS MOISTURE BEGINS TO SPILL EAST INTO THE AREA. THE INCREASING MOISTURE WILL RESULT IN INCREASING INSTABILITY SUNDAY WHICH SEVERAL MODELS KEY IN ON TO KICK OFF SHOWERS AND THUNDERSTORMS DURING THE DAY SUNDAY. SEVERAL OTHER MODELS SUGGEST A CAP WILL PREVENT SHRA/TSRA DURING THE DAY WITH THREAT CONFINED TO THE FRONTAL PASSAGE SUNDAY EVENING. GIVEN THE STRONGLY CONFLICTING MODEL GUIDANCE REGARDING THE THREAT OF TSRA DURING THE DAY...HAVE OPTED TO JUST INCLUDE VCTS IN THE TAFS FOR NOW WHILE CONTINUING THE TEMPO DURING THE EVENING WHEN THE HIGHER THREAT SHOULD EXIST WITH THE FRONT. SOUTHWEST WINDS WILL INCREASE LATER SUNDAY MORNING AND CONTINUE INTO THE AFTERNOON WITH THE STRENGTH OF THE GUSTINESS LIKELY TO HINGE ON THE EXTENT OF CLOUD COVER AND SHRA/TSRA. IZZI //ORD AND MDW CONFIDENCE...UPDATED 09Z... * HIGH CONFIDENCE IN ALL ELEMENTS TONIGHT. * LOW CONFIDENCE ON TSRA THREAT DURING THE DAY SUNDAY * MEDIUM CONFIDENCE IN WIND/GUST SPEEDS SUNDAY * MEDIUM CONFIDENCE IN TSRA SUNDAY EVENING IZZI //OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z... MONDAY...CHANCE OF TSTMS MONDAY NIGHT. TUESDAY...CHANCE OF TSTMS CONTINUES INTO TUESDAY. WEDNESDAY...SLIGHT CHANCE OF TSTMS. THURSDAY...NONE. FRIDAY...CHANCE OF TSTMS. 2% && .MARINE... 325 AM CDT MODERATE SOUTHERLY WINDS LIKELY THROUGH THIS EVENING UNTIL A WEAK COLD FRONT MOVES ACROSS THE LAKE TONIGHT. WILL CONTINUE SMALL CRAFT ADVISORY FOR NEARSHORE WATERS THIS AFTERNOON INTO TONIGHT...THOUGH GUIDANCE HAS BACKED OFF A BIT ON SPEEDS WHICH COULD BE REASONABLE GIVEN POTENTIAL FOR CLOUD COVER LIMITING HEATING A BIT. CONFIDENCE IS PRETTY LOW IN WINDS THIS AFTERNOON AND EVENING...SO NOT PLANNING ANY CHANGES TO GOING HEADLINES. GENERALLY LOOKING FOR WESTERLY WINDS BEHIND THE FIRST FRONT MONDAY INTO TUESDAY BEFORE HIGH PRESSURE MOVES IN WED/THUR RESULTING IN LAND/LAKE BREEZE CIRCULATIONS DOMINATING WIND FLOW. IZZI && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...2 PM SUNDAY TO 4 AM MONDAY. SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...2 PM SUNDAY TO 10 PM SUNDAY. && $$ 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
  [top] Area Forecast Discussion National Weather Service Lincoln IL 331 AM CDT Sun Jul 6 2014 .DISCUSSION... ISSUED 320 AM CDT Sun Jul 6 2014 SHORT TERM...Today through Tuesday night 00Z models continue an unsettled weather pattern through Tuesday but differ with their qpf fields and with MCS activity. Models continue to trend faster with cold frontal passage getting south of central IL Tue night. Daily chances of showers and thunderstorms through Tue in tropical airmass with dewpoints in the upper 60s and lower 70s and highs in the upper 80s today and Monday. SPC has slight risk of severe storms this evening along and nw of a Springfield to Rantoul line with highest chances of severe storms later this afternoon into the evening over northern IL, eastern IA and southern WI where stronger shear is. Most of central and southeast IL is in a slight risk of severe storms on Monday night with another MCS moving se into IL and this one should have more widespread heavier rain. Cold front to pass se through central IL Tue and continue good chances of showers and thunderstorms and highest chances shifting into southeast IL Tue afternoon/evening. SPC has slight risk of severe storms se of central/se IL Tuesday where airmass is more unstable. Highs Tue in the low to mid 80s with muggy dewpoints in the upper 60s and lower 70s still. LONG TERM...Wednesday through Saturday night. Quieter weather returns to IL Wed/Thu as weak high pressure settles into the Midwest with somewhat less humid air and highs 80 to 85F. High pressure shifts into the eastern Great Lakes region during Friday and New England Sat with return southerly flow setting back up over IL. This to bring increase warmth and humidity along with isolated showers and thunderstorms from Friday into Sat night. 07 && .AVIATION... ISSUED 1159 PM CDT Sat Jul 5 2014 The MCV will trigger showers and isolated thunderstorms mainly east of a line from Champaign to Taylorville through 08z-09z tonight. However, additional shower development behind the wave will extend across our northern terminals of PIA and BMI the rest of the night. Radar returns are already showing up behind the wave all the way to Galesburg. Thunder will be isolated, and may not get within 5 miles of any terminal site overnight. Better chances of thunder will come later Sunday afternoon and evening with the next shortwave, which will be able to tap better instability. The latest HRRR and 4km NCEP WRF continue to indicate spotty showers/storms across the northern half of our forecast area the rest of tonight. Will keep VCSH for PIA and BMI through morning. Have continued to include VCTS for Sunday afternoon and evening for all terminal sites. Kept VFR throughout the forecast, but MVFR will be possible in heavier rains. Winds will remain southerly overnight, then shift to the S-SW Sunday morning as speeds increase to 12G20kt. Winds will diminish below 10kt with sunset Sun eve, remaining SW. Shimon && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1256 AM CDT SUN JUL 6 2014 .DISCUSSION... 852 PM CDT LOW CIRCULATION CONTINUES TO MOVE ACROSS THE FORECAST AREA GENERATING LIGHT RAIN WITH A FEW POCKETS OF MODERATE RAIN BASED ON RECENT OBS. EVEN THE LIGHTEST RADAR RETURNS ARE PRODUCING ENOUGH RAIN TO WET THE GROUND ACROSS MOST OF THE CHICAGO METRO AREA WITH THE STEADIER LIGHT RAIN ALONG AND SOUTH OF INTERSTATE 80. MOVEMENT CONTINUES TO BE SWIFT SO ACTIVITY WILL BE WINDING DOWN THROUGH LATE EVENING. NO MAJOR CHANGES EXPECTED TO THE OVERNIGHT FORECAST AT THIS POINT WITH SUBSIDENCE BUILDING IN BEHIND THE CURRENT WAVE AND THE LOW LEVEL JET FOCUSING ACROSS MISSOURI AND SOUTH- CENTRAL/SOUTHEAST IOWA OVERNIGHT. HOWEVER...INCREASING MOIST ADVECTION OVERNIGHT MAY BE ENOUGH TO TRIGGER ISOLATED TO SCATTERED SHOWERS AND STORMS SO WILL MAINTAIN SLIGHT AND LOW CHANCE POPS...WITH NOTHING COHERENT TO SUPPORT AN INCREASE AT THIS TIME. MDB //PREV DISCUSSION... 228 PM CDT MAIN FORECAST CHALLENGES TODAY ARE DEALING WITH CONVECTIVE CHANCES THROUGH MIDWEEK...INCLUDING THE POTENTIAL FOR SEVERE WEATHER SUNDAY EVENING/NIGHT. REST OF TODAY AND TONIGHT... AREA OF RAIN ASSOCIATED WITH A REMNANT MCV CURRENTLY MOVING ACROSS THE RIVER CONTINUES TO SLOWLY ERODE TO OUR WEST THIS AFTERNOON AS IT OUTRUNS THE INSTABILITY TO THE WEST AND ENCOUNTERS DRIER AIR. HAVE DROPPED POPS TO SLIGHT CHANCE MAINLY IN OUR WEST/SOUTHWEST COUNTIES THIS EVENING TO ACCOUNT FOR THIS AREA POSSIBLY FESTERING...BUT QPF VALUES SHOULD BE LOW. MORE ROBUST CONVECTION IS EXPECTED ACROSS PORTIONS OF MISSOURI AND CENTRAL/DOWNSTATE ILLINOIS TODAY. LATE THIS EVENING AND ESPECIALLY OVERNIGHT...VERY MODEST INSTABILITY STARTS TO OVERSPREAD THE AREA. GFS INDICATES MUCAPE VALUES INCREASING TO AROUND 500 J/KG BY DAYBREAK TOMORROW OVER THE CHICAGO AREA WITH SLIGHTLY BETTER VALUES TO THE WEST. THERE DOES NOT APPEAR TO BE A WELL DEFINED LOW LEVEL JET TONIGHT HOWEVER THERE IS AN AREA OF MODERATE LOW/MID LEVEL THETA-E ADVECTION THAT PUSHES ACROSS THE AREA WHICH MAY BE SUFFICIENT TO KICK OFF SHOWERS AND THUNDERSTORMS GIVEN THE INCREASING INSTABILITY. THERE IS NO CONCERN FOR SEVERE WEATHER OVERNIGHT. SUNDAY... UPPER PATTERN BEGINS TO AMPLIFY SUNDAY AS A SHORTWAVE TROUGH DIGS ACROSS THE CANADIAN PRAIRIES WITH SURFACE CYCLOGENESIS OCCURRING NEAR LAKE SUPERIOR. THIS WILL DRIVE A COLD FRONT TOWARDS THE AREA WITH H85 THERMAL RIDGE AHEAD LAYING OUT ACROSS THE AREA AS TEMPERATURES PUSH 20C SUNDAY AFTERNOON/EVENING. THIS SHOULD SUPPORT SURFACE TEMPS PUSHING THE 90 MARK DEPENDING ON CLOUD COVER AND ANY LINGERING MORNING CONVECTIVE DEBRIS. PERSISTENT SOUTHWEST FLOW WILL ALSO ADVECT DEWPOINTS TO AROUND 70 INTO THE AREA. MODELS CONTINUE TO TRY TO GENERATE CONVECTION EARLY IN THE DAY SUNDAY WITH MLCAPE VALUES GROWING TO IN EXCESS OF 3000 J/KG...HOWEVER SYNOPTICALLY WE SEEM TO BE IN A FAVORABLE AREA FOR THE CAP TO HOLD MUCH OF THE DAY WITH LITTLE IN THE WAY OF FORCING WITH MID LEVEL HEIGHT TENDENCIES FAIRLY NEUTRAL. AS THE SURFACE FRONT AND BETTER MID LEVEL HEIGHT FALLS START TO APPROACH THE AREA IN THE EVENING...CHANCES FOR THUNDERSTORMS WILL INCREASE. DEEP LAYER SHEAR OF 30-40KT WILL BE SUFFICIENT TO SUSTAIN AN ORGANIZED SEVERE THREAT DESPITE FALLING A LITTLE BEYOND THE MOST FAVORABLE DIURNAL TIMING. IN ADDITION...PWATS OF AROUND 2 INCHES POOLING ALONG THE FRONT WILL RESULT IN EFFICIENT RAIN PRODUCERS SO WILL LIKELY HAVE TO MONITOR HYDRO CONDITIONS CLOSELY OVERNIGHT TOO. MONDAY THROUGH TUESDAY... THE UPPER LEVELS CONTINUE TO AMPLIFY EARLY NEXT WEEK WITH THE MIDLEVEL BAROCLINIC ZONE SETTLING TO OUR SOUTH BY TUESDAY. CHANCES FOR PRECIP WILL BE BEST SOUTHEAST OF I-57 MONDAY WHERE THE FRONTAL BOUNDARY IS PROGGED TO SLOWLY CONTINUE TO SAG SOUTH...THEN BY TUESDAY THERE WILL BE CHANCES FOR THUNDERSTORMS AREA WIDE AS COOLER MID LEVEL AIR OVERSPREADS THE REGION WITH STEEP LOW/MID LEVEL LAPSE RATES DEVELOPING AND MOST MODELS INDICATING A SHEARED VORT MAX DIGGING ACROSS THE REGION. WITH THE JET STREAM SAGGING SOUTH ACROSS THE AREA...FOR NOW AT LEAST IT APPEARS THAT DEEP LAYER SHEAR VALUES WILL BE STRONG ENOUGH THAT THERE IS SOME CONCERN FOR SEVERE WEATHER EACH DAY. WEDNESDAY THROUGH FRIDAY... LONG WAVE TROUGH IN PLACE ACROSS THE MIDWEST/GREAT LAKES MIDWEEK WILL GRADUALLY SLIDE TOWARDS THE ATLANTIC COAST BY FRIDAY WITH THE OVERALL PATTERN FLATTENING OUT AGAIN. SURFACE HIGH BUILDS OVERHEAD AND SHOULD PROVIDE QUIET CONDITIONS FOR THE LATTER HALF OF THE WEEK WITH RETURN FLOW BACK INTO THE AREA STARTING AS EARLY AS FRIDAY. TEMPERATURES WILL BE NEAR OR POSSIBLY SLIGHTLY BELOW NORMAL WEDNESDAY AND THURSDAY. WARMER TEMPERATURES ARE POSSIBLE BY FRIDAY BUT GFS IS MUCH QUICKER BRINGING THE THERMAL RIDGE BACK OVER THE AREA AS COMPARED TO THE ECMWF...SO GIVEN THE MODEL DIFFERENCES OPTED TO MAINTAIN GENERAL MODEL CONSENSUS FOR NOW. DEUBELBEISS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * CHANCE OF SHRA/TSRA LATE MORNING AND AFTERNOON SUNDAY * PERIOD OF SHRA/TSRA LIKELY LATER SUNDAY EVENING IZZI //DISCUSSION...UPDATED 06Z... VFR OVC WILL OVERSPREAD THE AREA OVERNIGHT AS MOISTURE BEGINS TO SPILL EAST INTO THE AREA. THE INCREASING MOISTURE WILL RESULT IN INCREASING INSTABILITY SUNDAY WHICH SEVERAL MODELS KEY IN ON TO KICK OFF SHOWERS AND THUNDERSTORMS DURING THE DAY SUNDAY. SEVERAL OTHER MODELS SUGGEST A CAP WILL PREVENT SHRA/TSRA DURING THE DAY WITH THREAT CONFINED TO THE FRONTAL PASSAGE SUNDAY EVENING. GIVEN THE STRONGLY CONFLICTING MODEL GUIDANCE REGARDING THE THREAT OF TSRA DURING THE DAY...HAVE OPTED TO JUST INCLUDE VCTS IN THE TAFS FOR NOW WHILE CONTINUING THE TEMPO DURING THE EVENING WHEN THE HIGHER THREAT SHOULD EXIST WITH THE FRONT. SOUTHWEST WINDS WILL INCREASE LATER SUNDAY MORNING AND CONTINUE INTO THE AFTERNOON WITH THE STRENGTH OF THE GUSTINESS LIKELY TO HINGE ON THE EXTENT OF CLOUD COVER AND SHRA/TSRA. IZZI //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH CONFIDENCE IN ALL ELEMENTS TONIGHT. * LOW CONFIDENCE ON TSRA THREAT DURING THE DAY SUNDAY * MEDIUM CONFIDENCE IN WIND/GUST SPEEDS SUNDAY * MEDIUM CONFIDENCE IN TSRA SUNDAY EVENING IZZI //OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z... MONDAY...CHANCE OF TSTMS MONDAY NIGHT. TUESDAY...CHANCE OF TSTMS CONTINUES INTO TUESDAY. WEDNESDAY...SLIGHT CHANCE OF TSTMS. THURSDAY...NONE. FRIDAY...CHANCE OF TSTMS. 2% && .MARINE... 206 PM CDT HIGH PRESSURE IS SLOWLY SHIFTING EAST WITH SOUTH WINDS ACROSS THE LAKE. WINDS WILL INCREASE TO 15-25 KT ACROSS ALL OF THE OPEN WATERS TONIGHT AS THE GRADIENT TIGHTENS AHEAD OF THE NEXT LOW. MAY SEE WINDS GET TO CLOSE TO 30 KT OVER THE NORTHERN HALF OF THE LAKE...BUT THINKING THE MARINE LAYER WILL BE STABLE ENOUGH TO KEEP HIGHER WINDS FROM REACHING THE SURFACE. WINDS SHOULD BECOME HAZARDOUS TO SMALL CRAFT TOMORROW AFTERNOON AND EVENING SO ISSUED A SMALL CRAFT ADVISORY FOR ALL OF THE NEARSHORE WATERS. HAVE THE SMALL CRAFT ADVSY LASTING 6 HOURS LONGER OVER NW INDIANA AS SW WINDS 20-25 KT SHOULD PERSIST THROUGH THE EVENING THERE. THE LOW PASSES OVER SOUTHERN ONTARIO TOMORROW AND TOMORROW NIGHT WITH ITS COLD FRONT SWEEPING THROUGH LATE TOMORROW NIGHT. WINDS DIMINISH AND BECOME W TO NW BEHIND THE FRONT. A WEAK COLD FRONT MOVES SOUTH THROUGH AT LEAST MID LAKE MONDAY NIGHT INTO TUESDAY WITH WINDS BECOMING N TO NE BEHIND IT. ANOTHER WEAK LOW SWINGS THROUGH TUESDAY AND WINDS BECOME NW. GUIDANCE THEN DIFFERS GREATLY ON THE PATTERN FROM WEDNESDAY ONWARD. IN GENERAL LOOKING AT LIGHT WESTERLY FLOW WITH HIGH PRESSURE LATE NEXT WEEK LEADING TO PERIODS OF ONSHORE FLOW. JEE && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...2 PM SUNDAY TO 4 AM MONDAY. SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...2 PM SUNDAY TO 10 PM SUNDAY. && $$ 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 National Weather Service Lincoln IL 1159 PM CDT Sat Jul 5 2014 .DISCUSSION... ISSUED 900 PM CDT Sat Jul 5 2014 A well-defined MCV continues to make progress across IL, with showers expanding farther south and east with time. The back edge of the precip is about to reach the IL river, while the leading edge has reached a line from just north of Springfield to near Champaign. Have increased PoPs to likely the rest of the evening following the projected path of the wave. After midnight, the HRRR and 4km WRF still indicate some redevelopment of showers and possibly a thunderstorm along a line from W-E across central IL. That convection timing is a bit uncertain, even at this late hour, so we will continue with chance PoPs after midnight north of I-72. Clouds will likely prevail overnight, which will help to keep low temps slightly warmer than under clear conditions. The low temp forecast appears reasonable, so will continue with low to mid 60s. Showers and storms are expected to redevelop late Sunday afternoon or evening as the next significant shortwave moves across IL. Instability params look favorable for a few strong to severe storms Sunday night. Main updates tonight were in the weather and PoP grids to match expected trends. Shimon && .AVIATION... ISSUED 1159 PM CDT Sat Jul 5 2014 The MCV will trigger showers and isolated thunderstorms mainly east of a line from Champaign to Taylorville through 08z-09z tonight. However, additional shower development behind the wave will extend across our northern terminals of PIA and BMI the rest of the night. Radar returns are already showing up behind the wave all the way to Galesburg. Thunder will be isolated, and may not get within 5 miles of any terminal site overnight. Better chances of thunder will come later Sunday afternoon and evening with the next shortwave, which will be able to tap better instability. The latest HRRR and 4km NCEP WRF continue to indicate spotty showers/storms across the northern half of our forecast area the rest of tonight. Will keep VCSH for PIA and BMI through morning. Have continued to include VCTS for Sunday afternoon and evening for all terminal sites. Kept VFR throughout the forecast, but MVFR will be possible in heavier rains. Winds will remain southerly overnight, then shift to the S-SW Sunday morning as speeds increase to 12G20kt. Winds will diminish below 10kt with sunset Sun eve, remaining SW. Shimon && .PREV DISCUSSION... ISSUED 300 PM CDT Sat Jul 5 2014 Models continue to look similar with overall upper level pattern and surface features. However, they still differ on the smaller/mesoscale features, which affect where and when pcpn will occur. So took a blend and tried to make adjustments with location and timing of pops in the short term, based on general synoptic feature forecast; and to stay in sync with surrounding offices. Main concerns will be chance pops through the forecast period, along with temps next couple of days. SHORT TERM...Tonight through Tuesday night Remnants of last night`s MCS is finally diminishing, as the HRRR model forecasted earlier this morning. Associated MCV will continue to move east over northern IL this evening, but will likely not do much as it will be moving into drier air. However, will be keeping chance pops in the area this evening and overnight as any leftover outflow boundaries could still produce some showers and thunderstorms. Area covered will be in the north and central, leaving the southeast dry. Another MCS is expected to develop late tonight back west where the boundary and best moisture is located at. This MCS is expected to move toward the area late tonight and into the area tomorrow. So will be keeping chc pops in the north and central parts of the cwa tomorrow. The outflow boundary from this MCS should have higher dewpoint air to work with in the area, so will have little higher pops for tomorrow night in the area, covering all the cwa. The chance of pcpn will continue Mon and Mon night as boundaries and moisture will still remain around the area. The front will also be getting closer to the cwa Mon night, but really get into the area for Tue and Tue night. This will bring likely pops into the cwa for the whole area sometime between Tue and Tue night. As the front moves through the area Tue night, pcpn chances will diminish to the northwest. Temps will be quite warm the next two days as the cwa will remain in the warm sector. Moisture will also be on the increase, so conditions will be humid/muggy at times; typical for July summer in central Illinois. LONG TERM...Wednesday through Saturday After the front passes Tue night, conditions will be dry the remainder of the week. Long term models show some pcpn coming back into the area from the west late in the week and into the weekend, but not confident with that forecast at the moment. So will opt to keep what the consensus models show for now. Later adjustments are likely with this type of pattern in the summer. Auten && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1125 PM CDT SAT JUL 5 2014 .UPDATE... ISSUED AT 1124 PM CDT SAT JUL 5 2014 UPDATE ON ZONES WILL BE OUT SHORTLY FOR DELETION OF THE ISOLATED THUNDERSTORMS OVER THE SOUTHEAST FOR THE REMAINDER OF TONIGHT. UPDATE ISSUED AT 644 PM CDT SAT JUL 5 2014 WILL MAKE A QUICK UPDATED TO ADJUST THE PRECIPITATION THIS EVENING. THUNDERSTORMS NOT FORMING ON THE OUTFLOW AS EXPECTED...SO LOWERED POPS. && .SHORT TERM /TONIGHT/... ISSUED AT 312 PM CDT SAT JUL 5 2014 MCV/MCS CURRENTLY EXITING THE AREA TO THE SOUTHEAST THIS AFTERNOON. TEMPS HAVE BEEN HELD BACK BUT ARE RECOVERING ACROSS THE WEST. WARM FRONT OVER NORTHERN MO THIS MORNING HAS BEEN REINFORCED BY OUTFLOW BOUNDARY FROM MESOSCALE SYSTEM...BUT SHOULD BEGIN TO LIFT NORTH DURING THE NIGHTTIME HOURS. MODELS AT ODDS ABOUT CONVECTION COVERAGE TONIGHT...BUT HINTING AT SOME DEVELOPMENT ALONG THE EDGE OF THE RETREATING WARM FRONT/OUTFLOW BOUNDARY THROUGH IOWA OVERNIGHT. WEAKEST PORTION OF THE H700 CAP FAVORS THE EASTERN AND SOUTHERN SECTIONS. HRRR REFLECTS SOME DEVELOPMENT WITH A BAND OF STORMS FORMING AFT 04Z NEAR I80 CORRIDOR...VARIOUS OTHER SOLUTIONS ALSO FAVOR SOME DEVELOPMENT OVER THE EAST OR ALONG THE IOWA/MO BORDER BETWEEN 00 AND 06Z AS NOCTURNAL LOW LEVEL JET INCREASES AND IMPINGES ALONG THE WARM FRONT/OUTFLOW BOUNDARY. WILL INCREASE POPS AGAIN BY MID TO LATE EVENING OVER THE EAST AND SOUTH...WEAK STEERING CURRENTS SUGGEST SOME SOUTHEASTERLY DRIFT ALONG THE BOUNDARY OVERNIGHT. ONCE AGAIN...IF CONVECTION GETS A BIT MORE ORGANIZED COULD SEE A QUICK INCH OR TWO TOTAL FROM ANY STRONGER CELLS THAT DEVELOP. WARM CLOUD DEPTHS PUSHING 13-14KFT AND PRECIPITABLE WATER STILL RUNNING 1.5 INCHES OVER THE SOUTHEAST THIRD. FOR NOW WILL NOT ISSUE HEADLINES AS COVERAGE IS EXPECTED TO BE LIMITED. AFTER LAST NIGHTS/THIS MORNING RAINFALL... GRIDDED FLASH FLOOD GUIDANCE HAS LOWERED TO 1 TO 1.5 INCHES OVER A GOOD SHARE OF THE SOUTH WITH 3 HOURLY GUIDANCE NEARING 2 INCHES OVER THE SAME LOCATIONS. THE SOUTHERN TWO TIER COUNTIES CONTINUE HIGHER...WITH 2 INCH VALUES FOR 1 HOUR AND 2 TO 3 INCH VALUES FOR 3 HOUR GUIDANCE. NEEDLESS TO SAY...NOT MUCH CAPACITY LEFT IN SOIL FOR ADDITIONAL RAINFALL OVER THE NEXT FEW DAYS. LOWS WILL CREEP UP TONIGHT. DESPITE THE LACK OF MUCH SUNSHINE THIS AFTERNOON...LOWS WILL REMAIN IN THE MID TO UPPER 60S AS DEW POINTS HAVE RISEN WITH THE RETURN OF MOISTURE TO THE AREA. .LONG TERM /SUNDAY THROUGH SATURDAY/... ISSUED AT 312 PM CDT SAT JUL 5 2014 LONG TERM FORECAST PERIOD WILL FEATURE RATHER ACTIVE WX AND AN OVERALL UPPER AIR PATTERN OF WESTERLIES INVOF OF IOWA...EVOLVING FROM BROAD NORTHWEST FLOW TO BROAD CYCLONIC FLOW. MAIN CHALLENGES EARLY IN THE PERIOD WILL BE TSRA CHANCES SUNDAY AFTN/EVE AS WELL AS LATE MONDAY INTO TUE. FCST PERIOD BEGINS WITH IOWA SOUTH OF THE WESTERLIES. SUNDAY IS EXPECTED TO BE MORE SUMMER-LIKE...WITH THERMAL RIDGING AND MOISTURE TRANSPORT RESULTING IN SEASONALLY HOT AND HUMID CONDITIONS. TEMPS RANGING FROM THE UPPER 80S TO MIDDLE 90S ALONG WITH DEWPOINTS IN THE 70S ARE EXPECTED. AN IMPULSE WILL SWEEP A COOL FRONT INTO THE STATE ON SUNDAY. QUESTION IS HOW FAR WEST ALONG THE FRONT WILL THE TSRA DEVELOP. ALTHOUGH INSTABILITY IS PROGGED TO BE RESPECTABLE...CAPPING WILL INCREASE TOWARD THE WEST ACROSS THE STATE. BEST CHANCES OF TSRA WILL BE IN EASTERN IOWA...WHERE THE CAP WILL BE WEAKER AND UPPER-LEVEL FORCING WILL BE STRONGER. LOW- LEVEL JET WILL INCREASE MOISTURE TRANSPORT BY LATE EVENING...SO HAVE BROUGHT CHANCE POPS ALONG THE SOUTHERN BORDER OF THE STAGE BY THAT TIME. FRONT IS EXPECTED TO BECOME QUASI-STATIONARY INVOF THE IA-MO BORDER BY LATE SUNDAY NIGHT. STRONGER H5 SHORTWAVE WILL BRING ANOTHER CHANCE OF TSRA BY LATE MON. BOTH THERMODYNAMIC AND KINEMATIC FORCING WILL BE STRONGER WITH THIS SYSTEM THAN THE ONE ON LATE SUN. THIS SHORTWAVE WILL PUSH ANOTHER COOL FRONT SOUTH THROUGH IOWA...EVENTUALLY OVERTAKING THE QUASI-STATIONARY BOUNDARY INVOF THE IA-MO BORDER. AMPLE INSTABILITY AHEAD OF THE ADVANCING FRONT IS EXPECTED TO PROMOTE SFC-BASED TSRA DEVELOPMENT. SHEAR PARAMETERS SUGGEST A FEW SUPERCELLS POSSIBLE EARLY WITH LARGE HAIL AND DAMAGING WINDS THE MAIN THREATS...BUT CANNOT RULE OUT AN ISOLATED TORNADO. THE CONVECTION IS EXPECTED TO GROW UPSCALE INTO AN MCS AND PUSH SOUTHEAST INTO THE EVENING. AFTER THE FROPA MONDAY NIGHT/TUE MORNING...CYCLONIC WESTERLIES WILL DOMINATE THE WX INTO LATER IN THE WEEK. NEXT CHANCE OF PCPN WILL ARRIVE THURSDAY INTO THURSDAY NIGHT AS A WEAK IMPULSE PASSES OVER THE REGION. THE 12Z ECMWF IS ADVERTISING A STRONGER SHORTWAVE BRINGING ANOTHER BOUNDARY THROUGH THE CWA ON SATURDAY. THE 12Z RUN WAS CONSISTENT IN THIS REGARD WITH THE 00Z RUN. THIS SOLUTION IS ADMITTEDLY DIFFERENT THAN LAST NIGHT/S LONG TERM PACKAGE WHICH KEPT THE ACTIVITY NORTH OF THE CWA. SHRA/TSRA WILL BE POSSIBLE WITH THIS BOUNDARY AS IT SWEEPS THROUGH THE CWA. THIS BOUNDARY WILL BRING A SLIGHTLY COOLER AIR MASS OVER THE CWA TO END THE WEEKEND. && .AVIATION...06/06Z ISSUED AT 1110 PM CDT SAT JUL 5 2014 COLD FRONT FROM NERN ND INTO CO WILL MOVE SOUTHEAST INTO IA SUN AND PASS SOUTHEAST OF THE STATE BY THE END OF THE FORECAST PERIOD. TWO FORECAST PROBLEMS ARE THE STRATUS TONIGHT AND THUNDERSTORMS TOMORROW. WILL LIKELY SEE WIDESPREAD MVFR AND IFR CONDITIONS IN STRATUS AND FOG OVERNIGHT INTO THE EARLY MORNING WITH CONDITIONS LIFTING BY MID TO LATE MORNING. THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE FRONT AFTER 18Z AND MOVE SOUTHEAST WITH THE FRONT. TRIED TO TIME THE PASSAGE OF THE FRONT AND THUS THE THUNDERSTORM CHANCES. BEST CHANCE FOR THUNDERSTORMS WILL BE OVER THE NORTHEAST. OUTLOOK...FRONT WILL DROP SOUTHEAST OF THE STATE SUNDAY NIGHT AND BECOME STATIONARY. A SECOND COLD FRONT WILL MOVE THROUGH THE AREAS MONDAY WITH ANOTHER CHANCE FOR THUNDERSTORMS MONDAY NIGHT INTO EARLY TUE. HIGH PRESSURE WILL BRING FAIR CONDITIONS TO THE STATE WED AND THU. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...MS JUL 14 SHORT TERM...REV LONG TERM...ZOGG AVIATION...MS JUL 14
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1117 PM CDT SAT JUL 5 2014 .UPDATE... ISSUED AT 644 PM CDT SAT JUL 5 2014 WILL MAKE A QUICK UPDATED TO ADJUST THE PRECIPITATION THIS EVENING. THUNDERSTORMS NOT FORMING ON THE OUTFLOW AS EXPECTED...SO LOWERED POPS. && .SHORT TERM /TONIGHT/... ISSUED AT 312 PM CDT SAT JUL 5 2014 MCV/MCS CURRENTLY EXITING THE AREA TO THE SOUTHEAST THIS AFTERNOON. TEMPS HAVE BEEN HELD BACK BUT ARE RECOVERING ACROSS THE WEST. WARM FRONT OVER NORTHERN MO THIS MORNING HAS BEEN REINFORCED BY OUTFLOW BOUNDARY FROM MESOSCALE SYSTEM...BUT SHOULD BEGIN TO LIFT NORTH DURING THE NIGHTTIME HOURS. MODELS AT ODDS ABOUT CONVECTION COVERAGE TONIGHT...BUT HINTING AT SOME DEVELOPMENT ALONG THE EDGE OF THE RETREATING WARM FRONT/OUTFLOW BOUNDARY THROUGH IOWA OVERNIGHT. WEAKEST PORTION OF THE H700 CAP FAVORS THE EASTERN AND SOUTHERN SECTIONS. HRRR REFLECTS SOME DEVELOPMENT WITH A BAND OF STORMS FORMING AFT 04Z NEAR I80 CORRIDOR...VARIOUS OTHER SOLUTIONS ALSO FAVOR SOME DEVELOPMENT OVER THE EAST OR ALONG THE IOWA/MO BORDER BETWEEN 00 AND 06Z AS NOCTURNAL LOW LEVEL JET INCREASES AND IMPINGES ALONG THE WARM FRONT/OUTFLOW BOUNDARY. WILL INCREASE POPS AGAIN BY MID TO LATE EVENING OVER THE EAST AND SOUTH...WEAK STEERING CURRENTS SUGGEST SOME SOUTHEASTERLY DRIFT ALONG THE BOUNDARY OVERNIGHT. ONCE AGAIN...IF CONVECTION GETS A BIT MORE ORGANIZED COULD SEE A QUICK INCH OR TWO TOTAL FROM ANY STRONGER CELLS THAT DEVELOP. WARM CLOUD DEPTHS PUSHING 13-14KFT AND PRECIPITABLE WATER STILL RUNNING 1.5 INCHES OVER THE SOUTHEAST THIRD. FOR NOW WILL NOT ISSUE HEADLINES AS COVERAGE IS EXPECTED TO BE LIMITED. AFTER LAST NIGHTS/THIS MORNING RAINFALL... GRIDDED FLASH FLOOD GUIDANCE HAS LOWERED TO 1 TO 1.5 INCHES OVER A GOOD SHARE OF THE SOUTH WITH 3 HOURLY GUIDANCE NEARING 2 INCHES OVER THE SAME LOCATIONS. THE SOUTHERN TWO TIER COUNTIES CONTINUE HIGHER...WITH 2 INCH VALUES FOR 1 HOUR AND 2 TO 3 INCH VALUES FOR 3 HOUR GUIDANCE. NEEDLESS TO SAY...NOT MUCH CAPACITY LEFT IN SOIL FOR ADDITIONAL RAINFALL OVER THE NEXT FEW DAYS. LOWS WILL CREEP UP TONIGHT. DESPITE THE LACK OF MUCH SUNSHINE THIS AFTERNOON...LOWS WILL REMAIN IN THE MID TO UPPER 60S AS DEW POINTS HAVE RISEN WITH THE RETURN OF MOISTURE TO THE AREA. .LONG TERM /SUNDAY THROUGH SATURDAY/... ISSUED AT 312 PM CDT SAT JUL 5 2014 LONG TERM FORECAST PERIOD WILL FEATURE RATHER ACTIVE WX AND AN OVERALL UPPER AIR PATTERN OF WESTERLIES INVOF OF IOWA...EVOLVING FROM BROAD NORTHWEST FLOW TO BROAD CYCLONIC FLOW. MAIN CHALLENGES EARLY IN THE PERIOD WILL BE TSRA CHANCES SUNDAY AFTN/EVE AS WELL AS LATE MONDAY INTO TUE. FCST PERIOD BEGINS WITH IOWA SOUTH OF THE WESTERLIES. SUNDAY IS EXPECTED TO BE MORE SUMMER-LIKE...WITH THERMAL RIDGING AND MOISTURE TRANSPORT RESULTING IN SEASONALLY HOT AND HUMID CONDITIONS. TEMPS RANGING FROM THE UPPER 80S TO MIDDLE 90S ALONG WITH DEWPOINTS IN THE 70S ARE EXPECTED. AN IMPULSE WILL SWEEP A COOL FRONT INTO THE STATE ON SUNDAY. QUESTION IS HOW FAR WEST ALONG THE FRONT WILL THE TSRA DEVELOP. ALTHOUGH INSTABILITY IS PROGGED TO BE RESPECTABLE...CAPPING WILL INCREASE TOWARD THE WEST ACROSS THE STATE. BEST CHANCES OF TSRA WILL BE IN EASTERN IOWA...WHERE THE CAP WILL BE WEAKER AND UPPER-LEVEL FORCING WILL BE STRONGER. LOW- LEVEL JET WILL INCREASE MOISTURE TRANSPORT BY LATE EVENING...SO HAVE BROUGHT CHANCE POPS ALONG THE SOUTHERN BORDER OF THE STAGE BY THAT TIME. FRONT IS EXPECTED TO BECOME QUASI-STATIONARY INVOF THE IA-MO BORDER BY LATE SUNDAY NIGHT. STRONGER H5 SHORTWAVE WILL BRING ANOTHER CHANCE OF TSRA BY LATE MON. BOTH THERMODYNAMIC AND KINEMATIC FORCING WILL BE STRONGER WITH THIS SYSTEM THAN THE ONE ON LATE SUN. THIS SHORTWAVE WILL PUSH ANOTHER COOL FRONT SOUTH THROUGH IOWA...EVENTUALLY OVERTAKING THE QUASI-STATIONARY BOUNDARY INVOF THE IA-MO BORDER. AMPLE INSTABILITY AHEAD OF THE ADVANCING FRONT IS EXPECTED TO PROMOTE SFC-BASED TSRA DEVELOPMENT. SHEAR PARAMETERS SUGGEST A FEW SUPERCELLS POSSIBLE EARLY WITH LARGE HAIL AND DAMAGING WINDS THE MAIN THREATS...BUT CANNOT RULE OUT AN ISOLATED TORNADO. THE CONVECTION IS EXPECTED TO GROW UPSCALE INTO AN MCS AND PUSH SOUTHEAST INTO THE EVENING. AFTER THE FROPA MONDAY NIGHT/TUE MORNING...CYCLONIC WESTERLIES WILL DOMINATE THE WX INTO LATER IN THE WEEK. NEXT CHANCE OF PCPN WILL ARRIVE THURSDAY INTO THURSDAY NIGHT AS A WEAK IMPULSE PASSES OVER THE REGION. THE 12Z ECMWF IS ADVERTISING A STRONGER SHORTWAVE BRINGING ANOTHER BOUNDARY THROUGH THE CWA ON SATURDAY. THE 12Z RUN WAS CONSISTENT IN THIS REGARD WITH THE 00Z RUN. THIS SOLUTION IS ADMITTEDLY DIFFERENT THAN LAST NIGHT/S LONG TERM PACKAGE WHICH KEPT THE ACTIVITY NORTH OF THE CWA. SHRA/TSRA WILL BE POSSIBLE WITH THIS BOUNDARY AS IT SWEEPS THROUGH THE CWA. THIS BOUNDARY WILL BRING A SLIGHTLY COOLER AIR MASS OVER THE CWA TO END THE WEEKEND. && .AVIATION...06/06Z ISSUED AT 1110 PM CDT SAT JUL 5 2014 COLD FRONT FROM NERN ND INTO CO WILL MOVE SOUTHEAST INTO IA SUN AND PASS SOUTHEAST OF THE STATE BY THE END OF THE FORECAST PERIOD. TWO FORECAST PROBLEMS ARE THE STRATUS TONIGHT AND THUNDERSTORMS TOMORROW. WILL LIKELY SEE WIDESPREAD MVFR AND IFR CONDITIONS IN STRATUS AND FOG OVERNIGHT INTO THE EARLY MORNING WITH CONDITIONS LIFTING BY MID TO LATE MORNING. THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE FRONT AFTER 18Z AND MOVE SOUTHEAST WITH THE FRONT. TRIED TO TIME THE PASSAGE OF THE FRONT AND THUS THE THUNDERSTORM CHANCES. BEST CHANCE FOR THUNDERSTORMS WILL BE OVER THE NORTHEAST. OUTLOOK...FRONT WILL DROP SOUTHEAST OF THE STATE SUNDAY NIGHT AND BECOME STATIONARY. A SECOND COLD FRONT WILL MOVE THROUGH THE AREAS MONDAY WITH ANOTHER CHANCE FOR THUNDERSTORMS MONDAY NIGHT INTO EARLY TUE. HIGH PRESSURE WILL BRING FAIR CONDITIONS TO THE STATE WED AND THU. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...MS JUL 14 SHORT TERM...REV LONG TERM...ZOGG AVIATION...MS JUL 14
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1152 PM CDT Sat Jul 5 2014 ...Updated for 06Z Aviation Forecast... .UPDATE... Issued at 950 PM CDT SAT JUL 5 2014 Short term models (HRRR, RAP13) continue to try to develop convection over eastern Kansas this evening, and it continues to not develop to this point. New NAM not as aggressive as previous two runs, but still has spotty precip and more persistent precip in east central KS through tonight. Water vapor imagery showing one mid- level shortwave trough move southeastward across central and eastern KS, and weak subsidence behind it may be helping to suppress evening convection in KS. Models do have postive theta-e advection in the 850 to 700 mb layer for later this evening through 1 AM, so have not removed POPs from eastern KS, but have dropped them for north central KS for tonight. Any thunderstorms that do form will obviously have the potential for heavy rain with precipitable water values near 2" and decent moisture transport evident at 850 mb. && .SHORT TERM...(This Evening through Sunday) Issued at 244 PM CDT SAT JUL 5 2014 Forecast today quickly challenged with mesoscale conditions as convective complex moved across eastern Nebraska in the early morning hours. An outflow boundary then moved southwest into northeast Kansas, through about Topeka to just east of Marysville. As southwesterly surface winds have strengthened through the day, they have worked to counter slightly reinforced outflow and push this boundary back to the north. Little progress was made on the east end, and appears as though the incoming upper shortwave evident on WV imagery will move across this boundary for the remainder of the afternoon and evening hours. While shear is not ideal, and high surface dewpoints not conducive for a high end wind threat, there is enough instability (2000-3000J/kg range) to consider hail and possibly locally heavy rainfall a threat if these storms develop and move through. Forecast is certainly probabilistic - GFS confines convection more east, as does the EC, although the EC is slower with its exit through the morning on Sunday. The HRRR and NAM extend area of convection farther westward from NE KS and drop cluster of precip south southeast across the area through the evening hours. Have played the forecast toward the latter, although kept coverage isolated in nature as it passes through. Can`t rule out a bust with precip, especially as you go west, but do think the far eastern counties will see hit and miss showers and thunderstorms as the evening goes on. Heat returns on Sunday as mid level temperatures climb under the shortwave ridge behind the departing shortwave trof. Have highs in the 90s with heat indices coming out in the 99-103 range as the dewpoints hold around 70 east to the 60s west...however western counties are hotter so in the end heat index differences are subtle at best. .LONG TERM...(Sunday Night through Saturday) Issued at 244 PM CDT SAT JUL 5 2014 By Sunday evening the cold front dips southward from central NE, straddling the KS and NE border near 00Z. The main upper trough positioned to our north and east at this time has given guidance lower confidence in precip developing near the weakly convergent frontal boundary until after midnight. Northern areas of the CWA have a slight chance for thunderstorms while most of the CWA remains dry. Monday afternoon will be another hot and humid day as the surface trough over western KS deepens, increasing southwesterly flow and mixing of warmer air aloft. Highs once again in the mid to upper 90s are likely with heat indices between 100 and 103 degrees. A more potent shortwave trough digs southward through the plains on Monday evening, shunting the cold front through the CWA by 18Z Tuesday. Showers and thunderstorms are likely across the Nebraska and northwest MO border, decreasing to a chance further south as the heavier precip bands follow the upper trough axis centered over central/northern MO. Wind shear through 6 KM increases overnight with the passing wave between 30 and 40 kts while MLCAPE is around 1500 J/KG. A few stronger storms cannot be ruled out, especially if they redevelop or are able to become sfc based in the afternoon. Winds shift back towards the south with another incoming upper wave expected Wednesday evening. Trends show the heavier precip bands to impact mainly north central and portions of central KS where highest pops were placed. Precipitation will wane as it lifts northeast through Thursday, replaced by temporary ridging on Friday. Saturday begins the unsettled pattern once again as northwest flow begins to bring another series of weak disturbances through the region. Highs behind the boundary Tuesday through Thursday will cool back to the 80s with lows in the upper 60s. Increased warm advection Friday and Saturday, raise temps once again to the 90s accompanied by lows in the 70s. && .AVIATION...(For the 06Z TAFs through 06Z Sunday Night) Issued at 1148 PM CDT SAT JUL 5 2014 Expect VFR conditions through Sunday. With high pressure over Gulf Coast and low pressure over western KS, expect southerly flow to continue. Winds on Sunday should be weaker/less gusty than those on Saturday. Cannot completely rule out an isolated thunderstorm in eastern KS the rest of tonight, but confidence is low and chances of occurring at FOE or TOP also low. Thus, have not added to TAF. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GDP SHORT TERM...67 LONG TERM...Bowen AVIATION...GDP
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
409 AM EDT SUN JUL 6 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 424 PM EDT SAT JUL 5 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A RIDGE FROM THE SW CONUS INTO THE NRN PLAINS AND A DOWNSTREAM WNW FLOW THROUGH THE NRN GREAT LAKES. A WEAK SHORTWAVE TROUGH OVER NW ONTARIO(NW OF LAKE SUPERIOR) COMBINED WITH 25-30 KNOT 850-750 MB INFLOW OF MODERATELY UNSTABLE AIR (MUCAPE VALUES OF 1000-1500 J/KG) AND 40 KNOT 0-6KM SHEAR SUPPORTED STRONG CONVECTION OVER NE MN AND ADJOINING PORTION OF ONTARIO. SOME SHRA/TSRA WERE ALSO SLIDING INTO LAKE SUPERIOR BUT WERE WEAKENING AS THE CONVECTION MOVED AWAY FROM THE MORE UNSTABLE AIR. OTHERWISE...SUNSHINE AND SSW FLOW WAA PUSHED TEMPS INTO THE UPPER 70S AND LOWER 80S. TONIGHT...EXPECT THAT THE ONGOING SHRA/TSRA INTO WRN LAKE SUPERIOR WILL CONTINUE TO WEAKEN AS THEY SLIDE TO THE EAST THROUGH THE NRN HALF OF LAKE SUPERIOR...PER RADAR TRENDS AND SHORT RANG HIGH RES MODELS. ADDITIONAL CONVECTION IS LIKELY TO DEVELOP UPSTREAM LATE THIS EVENING AS ANOTHER WEAK SHRTWV OVER SRN MANITOBA MOVES TOWARD THE AREA. HOWEVER...UNCERTAINTY IS MUCH HIGHER WITH THE POSSIBILITY OF MCS DEVELOPMENT AND ITS EVENTUAL TRACK. EXPECT THAT THE HIGHER SHRA/TSRA WILL REMAIN TO THE NORTH AND WEST OF UPPER MI BUT THAT SOME MAY MOVE INTO UPPER MI...ESPECIALLY AFTER 06Z. WITH ONLY LIMITED MUCAPE INTO THE 500-1000 J/KG RANGE...ANY TSTORMS SHOULD REMAIN BELOW SEVERE LIMITS. SUNDAY...THE BEST CHANCE FOR SHRA/TSRA IS EXPECTED DURING THE AFTERNOON AS A STRONGER SHRTWV AND COLD FRONT MOVE TOWARD THE AREA. THERE WILL BE A CONDITIONAL RISK FOR STRONG/SEVERE STORMS THAT DEPENDS ON THE AMOUNT OF THICKER CLOUDS THAT LINGER INTO THE AFTERNOON. IF ENOUGH CLEARING DEVELOPS FOR A FEW HOURS TO ALLOW TEMPS TO REBOUND INTO THE LOWER 80S(DEWPOINTS IN THE MID TO UPPER 60S)...MLCAPE VALUES INTO THE 1K-2K RANGE COMBINED WITH 0-6KM SHEAR OF 35-40 KNOTS WILL SUPPORT STRONG/SEVERE ORGANIZED STORMS. 0-1KM HELICITY/SHAPE IS ALSO FAVORABLE FOR SOME ROTATING STORMS/SUPERCELLS. IF MORE PROMINENT CLOUDS REMAIN INTO THE AFTERNOON...THE GREATER INSTABILITY AND SEVERE POTENTIAL WOULD BE MAINLY OVER WI AND POSSIBLY INTO THE FAR SRN CWA. NMRS SHRA/TSRA OVER CNTRL UPPER MI DURING THE AFTERNOON WILL SHIFT TOWARD THE S AND ERN CWA BY LATE AFTERNOON AND EVENING. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 406 AM EDT SUN JUL 6 2014 COOLER AND DRIER AIR WILL SLOWLY TAKE OVER ON MONDAY. A SECONDARY COLD FRONT INITIALLY STRETCHING FROM THE LOW NEARING THE ONTARIO/QUEBEC BORDER THROUGH THE N MN BORDER AT 12Z MONDAY WILL SLOWLY EDGE E...AS HIGH PRESSURE WEAK HIGH PRESSURE BUILDS IN. DESPITE HIGH PRESSURE SETTLING ACROSS UPPER MICHIGAN MONDAY NIGHT...THE 500MB TROUGH WILL LINGER...AND CONTINUE TO BRING ABOUT SEVERAL SMALL DISTURBANCES. UNSETTLED WEATHER...WITH OFF AND ON LIGHT SHOWERS WILL REMAIN POSSIBLE OVER MAINLY WESTERN UPPER MICHIGAN FOR THE FIRST HALF OF THE WORK WEEK. TEMPS IN THE 60S TO MID 70S WILL BE COMMON...WHICH IS BELOW NORMAL. MONDAY NIGHT INTO EARLY TUESDAY LOOKS TO BE THE BEST CHANCE OF SEEING PRECIPITATION.... CURRENTLY HAVE AROUND A QUARTER OF AN INCH GOING...BUT SOME GUIDANCE WAS INDICATING THE POTENTIAL FOR QUITE A BIT MORE OVER THE S HALF OF UPPER MI /CLOSER TO THE SFC LOW BRUSHING THE CWA/. ONLY EXPECTING A SLIGHT CHANCE OF THUNDERSTORMS...WITH A BETTER CHANCE WELL TO OUR S. ANOTHER LOW PRESSURE SYSTEM OVER FAR N ONTARIO TUESDAY AFTERNOON WILL SINK OVER N LAKE SUPERIOR TUESDAY NIGHT INTO WEDNESDAY...ALTHOUGH THE 06/00Z GFS IS AN OUTLIER AND DOESN/T REALLY HAVE THIS FEATURE AT THE SFC IT STILL HAS THE MAIN 500MB TROUGH DIVING IN ALOFT. DUE TO LIMITED MOISTURE...POPS WHERE KEPT IN THE CHANCE OR BELOW RANGE. AT THIS TIME...DRY HIGH PRESSURE IS EXPECTED TO SETTLE ACROSS THE UPPER GREAT LAKES REGION AT THE SFC AND ALOFT WEDNESDAY NIGHT THROUGH FRIDAY. THERE ARE SOME DISCREPANCIES TO THE 500MB TROUGH...AND HOW QUICKLY IT EXITS E. THE ECMWF IS THE QUICKEST TO BRING BACK RIDGING AT 500MB...WITH THE CANADIAN SOLUTION KEEPING A TROUGH ACROSS THE E HALF OF THE CWA INTO FRIDAY. A BLENDED SOLUTION LOOKS REASONABLE FOR THURSDAY AFTERNOON ON. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 130 AM EDT SUN JUL 6 2014 VFR CONDITIONS WILL CONTINUE FOR MOST OF THIS PERIOD. SOME SHOWERS ARE ALSO EXPECTED TO DEVELOP AND MOVE INTO THE CWA ON SUNDAY AND WHEN THEY DO...MVFR CONDITIONS ARE POSSIBLE WITH THE SHOWERS STARTING FIRST AT IWD AND LAST AT SAW. CONDITIONS SHOULD IMPROVE BACK TO VFR BY LATE SUN AFTERNOON AS A COLD FRONT MOVES THROUGH THE AREA. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 406 AM EDT SUN JUL 6 2014 FOG WILL CONTINUE ACROSS LAKE SUPERIOR INTO MONDAY. WINDS ARE EXPECTED TO BE BELOW 25KTS THROUGH THE PERIOD /OUTSIDE OF ANY STRONG SHOWERS OR THUNDERSTORMS/. LOW PRESSURE ACROSS N MINNESOTA AND W ONTARIO WILL DEEPEN SLIGHTLY OVER CENTRAL ONTARIO AND N LAKE SUPERIOR THIS EVENING...BEFORE MOVING ACROSS QUEBEC ON MONDAY. BRIEF HIGH PRESSURE WILL SLIDE ACROSS LAKE SUPERIOR MONDAY NIGHT...AS WEAK LOW PRESSURE PUSHES ACROSS LAKE MICHIGAN AND LAKE HURON ON TUESDAY. ANOTHER WEAK LOW ACROSS ONTARIO TUESDAY NIGHT IS EXPECTED TO SINK ACROSS LAKE SUPERIOR ON WEDNESDAY...BEFORE STRONGER HIGH PRESSURE SETTLES ACROSS THE UPPER GREAT LAKES WEDNESDAY NIGHT THROUGH AT LEAST THURSDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...KF AVIATION...07 MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
131 AM EDT SUN JUL 6 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 424 PM EDT SAT JUL 5 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A RIDGE FROM THE SW CONUS INTO THE NRN PLAINS AND A DOWNSTREAM WNW FLOW THROUGH THE NRN GREAT LAKES. A WEAK SHORTWAVE TROUGH OVER NW ONTARIO(NW OF LAKE SUPERIOR) COMBINED WITH 25-30 KNOT 850-750 MB INFLOW OF MODERATELY UNSTABLE AIR (MUCAPE VALUES OF 1000-1500 J/KG) AND 40 KNOT 0-6KM SHEAR SUPPORTED STRONG CONVECTION OVER NE MN AND ADJOINING PORTION OF ONTARIO. SOME SHRA/TSRA WERE ALSO SLIDING INTO LAKE SUPERIOR BUT WERE WEAKENING AS THE CONVECTION MOVED AWAY FROM THE MORE UNSTABLE AIR. OTHERWISE...SUNSHINE AND SSW FLOW WAA PUSHED TEMPS INTO THE UPPER 70S AND LOWER 80S. TONIGHT...EXPECT THAT THE ONGOING SHRA/TSRA INTO WRN LAKE SUPERIOR WILL CONTINUE TO WEAKEN AS THEY SLIDE TO THE EAST THROUGH THE NRN HALF OF LAKE SUPERIOR...PER RADAR TRENDS AND SHORT RANG HIGH RES MODELS. ADDITIONAL CONVECTION IS LIKELY TO DEVELOP UPSTREAM LATE THIS EVENING AS ANOTHER WEAK SHRTWV OVER SRN MANITOBA MOVES TOWARD THE AREA. HOWEVER...UNCERTAINTY IS MUCH HIGHER WITH THE POSSIBILITY OF MCS DEVELOPMENT AND ITS EVENTUAL TRACK. EXPECT THAT THE HIGHER SHRA/TSRA WILL REMAIN TO THE NORTH AND WEST OF UPPER MI BUT THAT SOME MAY MOVE INTO UPPER MI...ESPECIALLY AFTER 06Z. WITH ONLY LIMITED MUCAPE INTO THE 500-1000 J/KG RANGE...ANY TSTORMS SHOULD REMAIN BELOW SEVERE LIMITS. SUNDAY...THE BEST CHANCE FOR SHRA/TSRA IS EXPECTED DURING THE AFTERNOON AS A STRONGER SHRTWV AND COLD FRONT MOVE TOWARD THE AREA. THERE WILL BE A CONDITIONAL RISK FOR STRONG/SEVERE STORMS THAT DEPENDS ON THE AMOUNT OF THICKER CLOUDS THAT LINGER INTO THE AFTERNOON. IF ENOUGH CLEARING DEVELOPS FOR A FEW HOURS TO ALLOW TEMPS TO REBOUND INTO THE LOWER 80S(DEWPOINTS IN THE MID TO UPPER 60S)...MLCAPE VALUES INTO THE 1K-2K RANGE COMBINED WITH 0-6KM SHEAR OF 35-40 KNOTS WILL SUPPORT STRONG/SEVERE ORGANIZED STORMS. 0-1KM HELICITY/SHAPE IS ALSO FAVORABLE FOR SOME ROTATING STORMS/SUPERCELLS. IF MORE PROMINENT CLOUDS REMAIN INTO THE AFTERNOON...THE GREATER INSTABILITY AND SEVERE POTENTIAL WOULD BE MAINLY OVER WI AND POSSIBLY INTO THE FAR SRN CWA. NMRS SHRA/TSRA OVER CNTRL UPPER MI DURING THE AFTERNOON WILL SHIFT TOWARD THE S AND ERN CWA BY LATE AFTERNOON AND EVENING. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 330 PM EDT SAT JUL 5 2014 A SHORTWAVE TROUGH ALOFT AND SFC LOW WILL BE JUST N OF THE CWA WITH A COLD FRONT ACROSS THE CENTRAL CWA AT 00Z MON. CONVECTION...POSSIBLY SEVERE /SEE SHORT TERM DISCUSSION FOR MORE DETAILS ON SEVERE THREAT/...WILL BE ONGOING ALONG AND AHEAD OF THE FRONT OVER MAINLY THE ERN HALF OF THE CWA. BY 06Z MON...THE FRONT WILL HAVE MOVED TO THE ERN CWA...WITH MOST OF THE CONVECTION E OF THE CWA. ADDITIONAL SHORTWAVE ENERGY LOOKS TO MOVE N OF THE CWA DURING THE DAY ON MON...BUT FORCING WILL STAY N KEEPING THE CWA DRY FOR THE MOST PART. THE NAM IS SHOWING A SHORTWAVE MOVING IN MON EVENING...WHICH WOULD RESULT IN PRECIP LATE IN THE DAY OVER THE WRN CWA...BUT MOST OTHER MODELS SHOW THIS COMING IN MON NIGHT OR EVEN EARLY TUE. AS IS USUAL WITH SUBTLE SHORTWAVES AND ASSOCIATED CONVECTIVE COMPLEXES...CONFIDENCE IN EXACT DETAILS IS QUITE LOW THIS FAR OUT. CONFIDENCE CONTINUES TO BE LOW THROUGH THE MIDDLE OF THE WEEK AS MODELS INDICATE ADDITIONAL SHORTWAVE ENERGY MON NIGHT OR TUE...WHICH APPEARS TO STAY S OF THE CWA. YET ANOTHER SHORTWAVE IS MODELED TO MOVE OVER THE NRN CWA TUE NIGHT...BUT WITH LESS MOISTURE TO WORK WITH...PRECIP SHOULD BE CONFINED TO NEAR THE SHORTWAVE. WITH THE GENERAL TROUGHING OVER THE REGION THROUGH MIDWEEK...EXPECT TEMPS TO BE A LITTLE BELOW NORMAL. HOWEVER...UPPER RIDGING BUILDING INTO THE REGION LATER IN THE WEEK AND POSSIBLY INTO NEXT WEEKEND WILL LEAD TO AN ABOVE NORMAL TREND FOR TEMPERATURES. CONFIDENCE IS LOW THAT ANY SIGNIFICANT PRECIP WILL OCCUR THU THROUGH NEXT SAT...BUT THE BEST CHANCES FOR PRECIP WILL BE ON SAT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 130 AM EDT SUN JUL 6 2014 VFR CONDITIONS WILL CONTINUE FOR MOST OF THIS PERIOD. SOME SHOWERS ARE ALSO EXPECTED TO DEVELOP AND MOVE INTO THE CWA ON SUNDAY AND WHEN THEY DO...MVFR CONDITIONS ARE POSSIBLE WITH THE SHOWERS STARTING FIRST AT IWD AND LAST AT SAW. CONDITIONS SHOULD IMPROVE BACK TO VFR BY LATE SUN AFTERNOON AS A COLD FRONT MOVES THROUGH THE AREA. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 424 PM EDT SAT JUL 5 2014 HIGH PRESSURE ACROSS THE OHIO VALLEY WILL CONTINUE TO SLOWLY EXIT EASTWARD THROUGH SUNDAY. LOOK FOR THE RIDGE ACROSS UPPER MICHIGAN TO WEAKEN AS LOW PRESSURE NEAR S MANITOBA SUNDAY MORNING SLIDES ACROSS ONTARIO AND LAKE SUPERIOR SUNDAY AFTERNOON AND EVENING. THIS LOW WILL DEEPEN SW OF JAMES BAY LATE SUNDAY NIGHT AND MONDAY MORNING...WHILE DRAGGING A TROUGH AVERAGING ACROSS LAKE SUPERIOR. A WEAK TROUGH WILL REMAIN DRAPED ACROSS NORTHERN AND SOUTHEAST ONTARIO THROUGH WEDNESDAY A RIDGE BUILDS OVER THE NORTHERN HIGH PLAINS. WINDS SHOULD REMAIN AT OR BELOW 20 KNOTS...EXCEPT IN OR NEAR ANY STRONGER THUNDERSTORMS. FOG...POSSIBLY DENSE...WILL BE POSSIBLE FROM LATE TONIGHT THROUGH EARLY MONDAY MORNING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...07 MARINE...JLB
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
1215 AM CDT SUN JUL 6 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 105 PM CDT SAT JUL 5 2014 LOOKS LIKE ANOTHER NIGHT WITH SOME POTENTIAL FOR SHRA/TSRA ACROSS THE REGION... BUT ONCE AGAIN THE QUESTION IS WHETHER THAT POTENTIAL WILL BE REALIZED. WE SHOULD SEE STORMS DEVELOP TO OUR WEST ONCE AGAIN THIS AFTERNOON... WHICH WILL LIKELY GROW UP SCALE INTO AN MCS. IF THIS OCCURS OVER NORTH DAKOTA AS MOST OF THE MODELS GUIDANCE SUGGESTS... IT LOOKS LIKE THE BULK OF IT WOULD TRANSLATE EAST ALONG THE THICKNESS CONTOURS AND MISS US TO THE NORTH. THERE ARE SOME HINTS IN THE CAM SOLUTIONS THAT A SECOND COMPLEX COULD DEVELOP FARTHER SOUTH OVER SOUTH DAKOTA... BUT IF THAT WERE TO OCCUR IT WOULD LIKELY TRANSLATE MORE SOUTHEASTWARD AND MISS US TO THE SOUTHWEST/SOUTH. A THIRD POTENTIAL FOR STORMS WOULD ACTUALLY BE SOONER... DURING LATE AFTERNOON/EARLY EVENING OVER OUR NORTH CENTRAL AND NORTHEAST CWFA... IF ANYTHING MANAGES TO DEVELOP IN THE CU FIELD CURRENTLY IN PLACE SOUTH OF THE ONGOING CONVECTION OVER NORTHEAST MINNESOTA. A COUPLE OF HOPWRF MEMBERS HAVE SUGGESTED THAT IS POSSIBLE... BUT THE OTHER MEMBERS AS WELL AS THE HRRR KEEP ANY OF THAT NORTH OF THE AREA. SO... OVERALL THERE REMAINS SOME POTENTIAL FOR ACTIVITY TO DEVELOP AND/OR MOVE INTO PORTIONS OF THE AREA TONIGHT... BUT IT IS BY NO MEANS A SLAM DUNK. WILL ALLOW POPS TO INCREASE ACROSS THE NORTH SOME DURING THE EVENING AND OVERNIGHT HOURS... WITH THAT AREA LOOKING TO HAVE THE BEST POTENTIAL TO SEE SOMETHING. ANYTHING THAT/S OVER THE AREA LATE TONIGHT WOULD SHIFT EAST IN THE MORNING... SO TRANSLATED SOME CHANCE POPS EASTWARD. WE WOULD THEN NEED TO LOOK TOWARD DEVELOPING ALONG/AHEAD OF THE COLD FRONT... WHICH WILL MOVE ACROSS THE AREA DURING THE LATE MORNING AND EARLY AFTERNOON ACCORDING TO THE MAJORITY OF THE GUIDANCE. THAT TIMING IS NOT PARTICULARLY FAVORABLE FOR DEVELOPMENT ACROSS OUR AREA... AND WOULD MAINLY POINT TOWARD AREAS EAST OF I-35 HAVING A CHANCE OF SEEING SOMETHING DURING THE AFTERNOON. SO... PUT THE HIGHEST POPS ON SUNDAY AFTERNOON ACROSS THE EASTERN PORTION OF THE AREA. SHOULD STORMS DEVELOP OVER THE AREA ON SUNDAY... THEY WOULD CERTAINLY HAVE SOME POTENTIAL TO BE SEVERE GIVEN MLCAPE VALUES AOA 2500 J/KG AND 0-6KM SHEAR AOA 35 KT... SO IT CERTAINLY BEARS WATCHING AND WILL BE MORE OF A CONCERN SHOULD THE FRONTAL TIMING WIND UP SLOWER. WE WILL MAKE A RUN AT 90 ON SUNDAY DEPENDING UPON HOW MUCH CLOUD COVER WE SEE OVER THE AREA... WHICH COULD BE HIGHLY VARIABLE DEPENDING ON ANY ISSUES FROM OVERNIGHT CONVECTIVE DEBRIS AND SHRA/TSRA DEVELOPMENT DURING THE DAY. THE FAIRLY EARLY FROPA DOESN/T APPEAR TO HAVE MUCH OF AN IMPACT ON THE HIGH TEMPERATURE POTENTIAL... WITH MIXING ACTUALLY LOOKING TO INCREASE BEHIND THE FRONT WHILE TEMPERATURES ALOFT ARE STILL SUPPORTIVE OF HIGHS NEAR 90. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 105 PM CDT SAT JUL 5 2014 THE THUNDERSTORM AND SEVERE WEATHER POTENTIAL SHOULD BE SOUTH AND EAST OF THE FORECAST AREA BY SUNDAY NIGHT ALONG THE AFOREMENTIONED COLD FRONT. GOOD MID-LEVEL DRYING WILL ACCOMPANY THE COLD ADVECTION SUNDAY NIGHT...BUT THE DRYING SHOULD BE SHORT LIVED WITH A WAVE DROPPING SOUTH OUT OF MANITOBA AND INTO ND/MN BY MONDAY AFTERNOON. A BIT MID DECK OF STRATUS OR STRATO-CU MIGHT ACT TO SUPPRESS SBCAPE...BUT THERE SHOULD BE DECENT RECOVERY IN ELEVATED INSTABILITY BY MONDAY AFTERNOON WITH STEEPENING MID-LEVEL LAPSE RATES. A MID-LEVEL SPEED MAX IS ALSO EXPECTED TO DROP SOUTH OUT OF THE HIGH PLAINS AND SHOULD INCREASE THE DEEP LAYER SHEAR ACROSS AT LEAST THE WESTERN FORECAST AREA. THEREFORE...STORMS EMBEDDED IN THE NORTHWEST FLOW SHOULD POSE A HAIL THREAT. WOULD NOT BE SURPRISED TO SEE THE SPC SLIGHT RISK SHIFTED A LITTLE FARTHER NORTH WITH THE NEXT UPDATE. WE HAVE INCREASED THE POPS TO 30-50% ACROSS MUCH OF THE FORECAST AREA...WITH THE IDEA OF AT LEAST SCATTERED STORM COVERAGE WITH THE ADVANCING SHORTWAVE AS THE TRIGGER. THE BEST TIME FRAME FOR STRONG TO SEVERE STORMS WOULD BE IN THE VERY LATE AFTERNOON AND EVENING. CYCLONICALLY CURVED LONG WAVE PATTERN LINGERS THROUGHOUT AT LEAST MID WEEK. THIS SHOULD CONTINUE TO REINFORCE THE COOL EARLY START TO THIS JULY...WHICH SITS BETWEEN 4 AND 7 DEGREES BELOW NORMAL FOR THE FIRST FEW DAYS IN CENTRAL MN AND WEST CENTRAL WI. HEIGHTS BUILD LATE IN THE WEEK...BUT THE FLOW STILL REMAINS W-NW AND THE THERMAL RIDGE OUT ACROSS THE WESTERN CONUS AND HIGH PLAINS WILL STRUGGLE TO ADVANCE EAST. THIS IS SUPPORTED BY THE CFS...05.12Z GFS/ECMWF AND THEIR CORRESPONDING ENSEMBLE MEMBERS WHICH INDICATES A NEAR NORMAL TEMPERATURE...BUT OVERALL DRY PATTERN FOR AT LEAST THE NEXT COUPLE WEEKS LOCALLY. IT DOES MEAN IF WE DONT REACH 90 TOMORROW...IT MAY BE SOME TIME BEFORE WE GET CLOSE TO THAT AGAIN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1159 PM CDT SAT JUL 5 2014 LOW CIGS AND VSBYS ARE IN PLACE AT TAF ISSUANCE TIME OVER NRN IA INTO SERN MN AND WRN WI. EAU AND RNH WILL BE MVFR OR IFR THROUGH TONIGHT INTO SUNDAY MORNING...BUT THERE WILL BE SOME BUILDING OF THIS TO THE NORTHWEST AS WELL...SO MSP IS NOT OUT OF THE WOODS EITHER...ALBEIT IT IS MORE UNCERTAIN THERE. TOUGH TO SAY HOW LOW VISIBILITIES MAY GET WITH THE LOW CLOUDS AND PERSISTENT SOUTHERLY FLOW IN PLACE BUT SEVERAL OBS IN NRN IA ARE LESS THAN 3SM AND IN SOME CASES LESS THAN 1SM. CONDITIONS SHOULD IMPROVE AFTER 14-15Z. THUNDERSTORMS TONIGHT HAVE BEEN CONFINED TO NORTHERN MN. A FEW CELLS MAY WORK DOWN TOWARD AXN OR STC DURING THE NEXT FEW HOURS...BUT THEY WOULD BE ENCOUNTERING A LESS FAVORABLE ENVIRONMENT. THUS...REMOVED MENTION OF TS FROM THE TAFS. BETTER CHANCE OF TS WILL COME EARLY SUNDAY AFTERNOON ACROSS WRN WI. KMSP...THERE WAS A BRIEF INSTANCE OF MVFR CIGS LATE THIS EVENING... HOWEVER THE CIGS HAVE RETREATED BACK TOWARD WI. THINKING THEY WILL BUILD NORTHWEST AGAIN OVERNIGHT BUT THE TERMINAL SHOULD BE ON THE NORTHWEST PERIPHERY. THUS...FELT MOST COMFORTABLE WITH TEMPOS AT THIS POINT. /OUTLOOK FOR KMSP/ MONDAY...VFR. WEST WIND 5 TO 15 KT. TUESDAY...VFR. NORTHWEST WIND 10 TO 20 KT. WEDNESDAY...VFR. WEST WIND 5 TO 10 KT. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...TRH LONG TERM...CLF AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1203 AM CDT Sun Jul 6 2014 .SHORT TERM...(Tonight into Sunday) Issued at 254 PM CDT SAT JUL 5 2014 Currently, large expanse of high level clouds have enveloped much of the outlook area. This is blow off from a convective complex to our north. Over the past few hours, this area of showers and storms has rapidly decayed, with just a few lingering showers near northern portions of Miller/Maries counties. This activity will dissipate over the next hour or so, with additional development expected later. Temperatures have been affected, somewhat, by the high cloud coverage, with most locations in the upper 70s to lower 80s. The only exception is across extreme southeastern Kansas and western Missouri where mid/upper 80s are a bit more common. Anticipate that scattered TSRA will redevelop to the northwest of the CWA later today in line with the HRRR and NAM12...however models handling how this will propagate inconsistently. Given orientation of the moisture transport/low level Theta E would anticipate activity to build southwestward into the night...then take on an easterly component toward morning as the relatively weak low level jet veers east. Questions for convection then on Sunday more of a question. Should be plenty of instability and even a bit of support from a dampening short wave. However rain may be hard to come by unless the overnight convection is able to generate an outflow boundary. .LONG TERM...(Sunday night through Friday) Issued at 254 PM CDT SAT JUL 5 2014 Warming trend will continue into Monday with areas over the west witnessing the highest heat indices of the season before heights start to fall and a wavy weak front arrives on Tuesday. Models have been consistent with convective development along the front Tuesday into early Wednesday as the front slowly descends into Arkansas. Questions continue as to how far south the front makes it into Arkansas and scattered storms may then continue along the Arkansas border through the end of the work week. && .AVIATION...(For the 06Z TAFS through 06Z Sunday Night) Issued at 1143 PM CDT SAT JUL 5 2014 VFR conditions are expected through Sunday evening. An upper level disturbance will bring an increase in mid and high clouds into Sunday morning. We do expect a few showers and perhaps a thunderstorm or two across portions of western Missouri from late tonight into Sunday morning. We have opted to include vicinity showers at Joplin as thunderstorm coverage is expected to be limited. Otherwise, we are expecting dry conditions to persist with continued south winds at the surface. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ SHORT TERM...Gagan/Runnels LONG TERM...Runnels AVIATION...Schaumann
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
311 AM CDT SUN JUL 6 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 311 AM CDT SUN JUL 6 2014 THERE ARE THREE PRIMARY FORECAST CHALLENGES CURRENTLY BEING CONSIDERED: -HEAT INDEX VALUES TODAY -CONVECTION CHANCES THIS AFTERNOON AND EVENING IN THE SOUTH -SEVERE AND HEAVY RAIN POTENTIAL FOR MONDAY AFTERNOON AND NIGHT AT 07Z...SURFACE COLD FRONT WAS ANALYZED FROM NORTH CENTRAL SOUTH DAKOTA INTO FAR NORTHWEST NEBRASKA AND HAD JUST MOVE THROUGH PINE RIDGE. FRONT SHOULD REACH SOUTHEAST NEBRASKA BY LATE AFTERNOON. AIRMASS OVER FORECAST AREA AHEAD OF THE FRONT WILL BE QUITE HUMID WITH DEWPOINTS IN THE LOW TO MID 70S...WITH ONLY SLIGHT COOLING BEHIND THE FRONT. ALOFT...WEAK RIDGING WAS NOTED UPSTREAM WITH MINOR HEIGHT RISES AT 500 MB ACROSS THE DAKOTAS INTO NEBRASKA...WITH FAIRLY WARM MID LEVEL TEMPERATURES. THEREIN LIES THE QUESTION OF THE PAST COUPLE OF DAYS...TRYING TO DETERMINE WHETHER THE FRONT WILL BE ABLE TO TRIGGER CONVECTION TODAY IN A WARM AIRMASS WITH A MODEST CAP AND A LACK OF DEEP VERTICAL MOTION FROM ANY DISTINCT LIFTING MECHANISM OTHER THAN THE FRONT. THE 00Z NAM AND THE 06Z RAP ARE IN GOOD AGREEMENT WITH DEVELOPING CONVECTION ALONG THE FRONT IN THE 22Z-23Z TIME FRAME...AND THE 00Z GFS DEVELOPS IT SLIGHTLY POST FRONTAL BETWEEN 00Z-06Z. NOT SURPRISINGLY...THE NAM AND RAP BOTH ERODE THE CAP FROM ABOUT LINCOLN SOUTH...AND INDICATE VERTICAL MOTION ON THE ORDER OF -4 MICROBARS/SEC THROUGH AROUND 600MB. GIVEN THESE POSSIBLE SCENARIOS...WILL GO WITH A SLIGHT CHANCE IN SOUTHEAST NEBRASKA/SOUTHWEST IOWA FROM 22Z-03Z. REGARDING THE HEAT AND HUMIDITY TODAY...THE COOLING BEHIND THE FRONT IS A CONCERN BUT NEARLY FULL SUN SHOULD KEEP TEMPERATURES FROM DROPPING MUCH. A DEGREE OR TWO DROP IN DEWPOINTS IS EXPECTED IN NORTHERN COUNTIES...BUT NOT IN SOUTHERN COUNTIES UNTIL WELL AFTER THE FRONT PASSES. GENERALLY HAVE NOT MADE CHANGES TO TEMPS TODAY...BUT DID RAISE DEWPOINTS A FEW DEGREES BASED ON READINGS SATURDAY. BOTTOM LINE IS HEAT INDEX VALUES OF 95-100 NORTH AND 100-105 SOUTH. LOOKS LIKE MOST SOUTHERN COUNTIES WILL REMAIN JUST SHY OF HEAT ADVISORY CRITERIA. MODELS IN REASONABLY GOOD AGREEMENT WITH WET PATTERN FOR MONDAY AFTERNOON INTO MONDAY NIGHT. CURRENT FORECAST HAS THIS PERIOD HANDLED WELL. ONLY CHANGES WILL BE TO INCREASE POPS FOR NORTHWEST AREAS MONDAY AFTERNOON...AND ALSO MENTION HEAVY RAIN MONDAY NIGHT ESPECIALLY SOUTH OF I-80 WHERE RECENT RAINS HAVE CAUSED FLOODING IN SOUTHWEST IOWA. HEAVY RAIN OVER THE SOUTHERN COUNTIES LOOKS POSSIBLE GIVEN THE STRONG FRONTAL CONVERGENCE IN THE LOW LEVELS FOR 9-12 HOURS... JET DIVERGENCE AND SHEARED VORTICITY IN NORTHWEST FLOW CAUSING A PROLONGED PERIOD OF LIFT...AND ABUNDANT MOISTURE/INSTABILITY. NAM AND GFS SHOW QUITE STRONG THETA-E ADVECTION FROM 850-700. THIS IS A CONCERN GIVEN THE CURRENT FLOODING IN THE NISHNABOTNA RIVER BASIN IN SOUTHWEST IOWA. WPC DAY 2 EXCESSIVE RAIN GRAPHIC SUPPORTS THIS AS WELL. INGREDIENTS FOR SEVERE CONVECTION MONDAY AFTERNOON AND EVENING APPEAR TO BE LINING UP...PER SPC DAY 2 DISCUSSION. INSTABILITY AND DEEP LAYER SHEAR PARAMETERS MORE THAN SUPPORT A SEVERE WEATHER OUTBREAK WITH UNSEASONABLY FAST UPPER FLOW. BOWING SEGMENTS ALONG THE FRONTAL BOUNDARY IN SOUTHEAST NEBRASKA/SOUTHWEST IOWA SEEM LIKELY. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 311 AM CDT SUN JUL 6 2014 BY LATE TUESDAY THE PRIMARY SYNOPTIC FRONT SHOULD MOVE WELL SOUTH OF THE AREA WITH SURFACE HIGH PRESSURE MOVING INTO THE FORECAST AREA. DRY CONDITIONS ARE EXPECTED TUESDAY NIGHT INTO WEDNESDAY. BY THURSDAY...RETURN FLOW BRINGS MOISTURE BACK INTO THE REGION AND THE UPPER PATTERN MAINTAINS A SOMEWHAT UNSETTLED NORTHWEST FLOW REGIME WITH SOME POTENTIAL FOR MCS ACTIVITY...BUT CONFIDENCE IS LOW THURSDAY INTO SATURDAY. TEMPERATURES SHOULD BE CLOSE TO NORMAL OR A FEW DEGREES BELOW NORMAL. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1055 PM CDT SAT JUL 5 2014 SOME FOG IS POSSIBLE AT ALL THREE SITES LATER TONIGHT AND EARLY SUNDAY WITH RECENT RAINS AND FORECASTED LOW DEWPOINT DEPRESSIONS/LIGHT OR NEARLY CALM WIND. CONVECTIVE DEBRIS WITH INCREASING HIGH CLOUDS SHOULD TEMPER THIS...BUT DID INCLUDE A TEMPO GROUP MAINLY BETWEEN 09-13Z. A COLD FRONT WILL MOVE INTO THE AREA WITH WINDS SHIFTING TO THE NORTHWEST BETWEEN 15-18Z AT KOFK AND CLOSER TO 21Z AT KOMA AND KLNK. VERY WARM MID LEVEL TEMPERATURES ARE IN PLACE...HOWEVER HEATING WELL INTO THE 90S...WEAK LIFT...AND STEEP LAPSE RATES COULD BE ENOUGH TO BREAK THE CAP AND ALLOW THUNDERSTORMS TO DEVELOP. OR...THE CAP MAY HOLD. THINK THERE IS ENOUGH OF A POSSIBILITY TO INCLUDE VCTS AT 21Z/22Z AT KLNK WITH THE FRONT PASSING THROUGH AT PEAK HEATING. MAY HAVE TO INCLUDE AT OMAHA DEPENDING ON HOW THINGS DEVELOP. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...NIETFELD LONG TERM...NIETFELD AVIATION...ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1245 AM CDT SUN JUL 6 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 305 PM CDT SAT JUL 5 2014 MAIN FORECAST CONCERNS WILL BE SHOWERS AND THUNDERSTORMS SOUTHEAST THIS AFTERNOON AND EVENING AND AGAIN LATE SUNDAY AFTERNOON...AND TEMPERATURES. CLOUDS HAVE ABOUT MOVED OUT OF THE FORECAST AREA THIS AFTERNOON BUT A FEW THIS AFTERNOON HAVE DEVELOPED ON THE EASTERN FRINGES OF THE FORECAST AREA AND PRODUCED A FEW SPRINKLES. AN UPPER LEVEL WAVE MOVES THROUGH THE AREA LATE THIS AFTERNOON AND EVENING. MODELS HAVE SOME DIFFERENCES IN THE STRENGTH OF THE WAVE AND WHAT HAPPENS AS IT MOVES THROUGH. THE NAM...THE RAP AND THE HRRR PRODUCE A LITTLE QPF/THUNDERSTORMS JUST TO THE SOUTHEAST OF THE FORECAST AREA FOR A BRIEF PERIOD LATE THIS AFTERNOON AND EARLY THIS EVENING. WITH THE SPRINKLES THAT FORMED EARLIER BELIEVE THAT A 20 PERCENT CHANCE COULD BE A GOOD IDEA IN THE FAR SOUTHEAST. NOT EXPECTING THERE TO BE MUCH BUT A FEW STORMS COULD DEVELOP. A SURFACE LOW AND COOL FRONT HAVE STARTED TO DEVELOP ON THE HIGH PLAINS THIS AFTERNOON. THIS FRONT APPROACHES THE FORECAST AREA TONIGHT AND MOVES INTO THE AREA DURING THE DAY SUNDAY. EVEN WITH THE FRONT MOVING INTO THE AREA THE TEMPERATURES ARE EXPECTED TO RISE WELL INTO THE 90S TO AROUND 100 DEGREES DURING THE DAY. AS THE FRONT MOVES THROUGH THE AREA...THERE IS A WEAK UPPER LEVEL WAVE THAT MOVES THROUGH THE AREA AS WELL. HAVE KEPT THE SMALL POPS IN FOR MUCH OF THE AREA DURING THE LATE AFTERNOON SUNDAY. THE MODELS HAVE DIFFERENCES ON THIS AS WELL. MANY OF THE MODELS ARE DRY...BUT A FEW SHOW SOME THUNDERSTORMS NEAR AND NORTH OF THE FRONT LATE IN THE AFTERNOON. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 305 PM CDT SAT JUL 5 2014 PATTERN: IT IS LOOKING DECIDEDLY MORE SUMMERLIKE. OVERALL THE MEAN LONGWAVE FLOW WILL FEATURE A WRN USA RIDGE/ERN USA TROF WITH SEASONABLE CHANGES IN AMPLITUDE. ONE THING IS CLEAR...WE HAVE TRANSITIONED TO A CONSIDERABLY DRIER PATTERN. THE PATTERN THAT BROUGHT THE VERY WET JUNE IS NO LONGER WITH US...AND ABOVE NORMAL HEIGHTS FCST OVER THE WRN AND CNTRL USA THRU MID-MONTH THREATEN SOME PERSISTENCE TO THIS DRYNESS. THE ONLY DECENT PROSPECT FOR MEANINGFUL RAIN FOR THE NEXT 7 DAYS IS MON NIGHT AND EVEN THEN NOT ALL AREAS WILL GET IT. EXPECT IRRIGATION WILL BE NECESSARY VERY SOON. ONE THING NOTED BY THE WPC /WX PREDICTION CTR AT NWSHQ/ IS TYPHOON NEOGURI FCST TO RECURVE IN THE WRN PACIFIC. ITS EXTRATROPICAL TRANSITION AND ABSORPTION INTO THE WESTERLIES COULD RESULT IN A PATTERN RE-ADJUSTMENT AROUND MID-MONTH. ALOFT: THE SUMMERTIME SUBTROPICAL HIGH HAS FINALLY DEVELOPED AND WILL BE OVER THE SW USA THRU MID-WEEK. STORMINESS OVER THE GULF OF AK WILL FORCE A TEMPORARY AMPLIFICATION OF THE RIDGE INTO WRN CANADA. THIS WILL LOWER HEIGHTS AND SEND A SHOT OF COOLER AIR INTO THE CNTRL/ERN USA THIS WEEK. THE ASSOCIATED TROF WILL SLIDE THRU MON NIGHT FOLLOWED BY CYCLONIC NW FLOW TUE-WED. A SHORTWAVE RIDGE WILL MOVE THRU THU AHEAD OF A TROF MOVING IN OFF THE PACIFIC. WHILE THE ENSEMBLE MEANS KEEP THIS TROF WILL ACTUALLY STAY N OF THE BORDER... ALLOWING HEIGHTS TO RISE AND THE SUBTROPICAL HIGH TO EXPAND ACROSS THE SRN 2/3 OF THE CONUS...AM NOT BUYING IT. THE PAST 2 EC/GEM/GFS CYCLES HAVE AMPLIFY THE PATTERN WITH THE ERN USA TROF BEING CARVED OUT AGAIN. THE 00Z EC ENSEMBLE CONTROL RUN SHOWS THIS VERY NICELY AND THIS IDEA FITS THE PATTERN. SURFACE: THE COOL FRONT THAT IS ADVANCING THRU THE FCST AREA SUN AFTERNOON WILL STALL OVER NRN KS MON...AWAITING A STRONGER SECOND FRONT THAT WILL SLIDE THRU MON NIGHT. THIS SECOND PUSH WILL FORCE THE COMPOSITE FRONT DEEPER INTO THE SRN PLAINS. COMFORTABLE HIGH PRES BUILDS IN TUE-WED WITH RETURN FLOW DEVELOPING THU AS THE HIGH HEADS INTO THE GREAT LAKES. LOW PRES WILL CROSS WRN CANADA DURING THIS TIME FRAME AND BEGIN DRAWING THE FRONT BACK N AS A WARM FRONT THU. FRI IT HEATS BACK UP IN THE WARM SECTOR...THEN A COOL FRONTAL PASSAGE FRI NIGHT OR SAT. HAZARDS: AN ISOLATED PROBABLY NON-SVR TSTM OR TWO IS POSSIBLE SUN NIGHT INTO MON. THE MAIN SHOW WILL BE MON NIGHT WITH LEGIT SVR POTENTIAL. BEYOND THAT...ANY TSTM DEVELOPMENT LOOKS UNORGANIZED AND IS LOW CONFIDENCE. THE DAILY DETAILS... UNCERTAINTY IS WAY ABOVE AVERAGE SUN NIGHT INTO MON. AM NOT IMPRESSED WITH THE TSTM POTENTIAL ALONG THIS FRONT. WHILE DEWPOINTS ARE IMPRESSIVE NOW...TOMORROW`S HEAT WILL MIX OUT THESE HIGH DWPTS WITH NO REPLENISHMENT. 12Z SOUNDINGS AROUND THE REGION THIS AM SHOW THERE ARE REALLY NO GOOD/DEEP BANDS OF MOISTURE. THIS LACK OF MOISTURE WILL MAKE IT MORE DIFFICULT TO BREAK THE CAP. 09Z SREF DOES SUGGEST PORTION OF THE NARROW RIBBON OF 10-12C 850 MB DWPTS ALONG THE FRONT WILL CIRCULATE ANTICYCLONICALLY BACK INTO THE REGION LATE SUN NIGHT INTO MON...WAITING TO INTERCEPT THE NEXT FRONT. BOTTOM LINE...MOST LOCATIONS WILL REMAIN DRY MOST OF THE TIME SUN NIGHT INTO MON. THIS FCST WOULD BETTER BE VIEWED FROM THE STANDPOINT THAT THERE IS AN 80% CHANCE THAT TSTMS WILL NOT FORM. "IF" AN ISOLATED TSTM OR TWO MANAGES TO DEVELOP...DEEP LAYER SHEAR WILL BE WEAK /10-15 KTS/. THIS SUGGESTS AT BEST NICKEL SIZE HAIL. LCL HEIGHTS WILL BE NEAR 10K FT WHICH WOULD THREATEN WIND GUSTS UP TO 50 MPH. MON NIGHT: A COOL FRONTAL PASSAGE WITH A TIGHT PRES GRADIENT BEHIND AND THE LLJ IN ADVANCE. CONSIDERABLE CONVERGENCE SHOULD RESULT IN TSTM DEVELOPMENT. THE PRECONVECTIVE ENVIRONMENT SHOULD HAVE 2000- 2500 J/KG OF MLCAPE WITH 40-45 KTS OF EFFECTIVE SHEAR. WE DO NEED TO WATCH POTENTIAL FOR INITIAL DEVELOPMENT FOR SUPERCELL POTENTIAL... BUT THE STRENGTH OF THE FORCING SHOULD RESULT IN RAPID DEVELOPMENT OF A SQUALL LINE WITH DAMAGING WIND BEING THE PRIMARY THREAT. GIVEN THE STRENGTH OF THE LOW-LEVEL SHEAR...EMBEDDED BOWS AND LEWP`S WILL BE POSSIBLE. WE HAVE NOTED THE SPC SLIGHT RISK FOR SVR WX AND WE ARE IN AGREEMENT. THIS FCSTR CONTS TO SEE TUE-THU COOLER THAN WHAT MEX MOS AND EVEN THE DAYS 4-7 INITIALIZATION HAVE BEEN ADVERTISING. THIS GUIDANCE HAS BEEN VERY RELUCTANT TO LOWER TEMPS. BASED ON ENSEMBLE TEMP ANOMALIES ...HAVE TRENDED THE FCST HIGHS CLOSER TO THE EC/GEM 2M TEMPS WHICH HAVE HAD A SIZABLE COOLDOWN FOR SEVERAL DAYS. TUE: CLEARING AS MON NIGHT`S MCS DEPARTS THE REGION. HIGHS HAVE BEEN LOWERED TO 77-86F...A LITTLE BELOW THE 4 AM GID FCST. THIS IS ROUGHLY 8F COOLER THAN NORMAL. THERE COULD BE A PERIOD OF WINDY CONDITIONS BEFORE NOON. WED: VERY NICE. TEMPS BEGIN CREEPING UP A LITTLE...BUT STILL 4-5F COOLER THAN NORMAL. WED NIGHT: GOOD LLJ DEVELOPMENT WITH A BURST OF THETA-E ADVECTION. COULD SEE A FEW SHWRS/TSTMS FORM WITH THE APPROACHING WARM FRONT. THU: QUESTIONABLE. IT ALL DEPENDS ON HOW QUICKLY WARM FRONTAL CLOUDINESS DEPARTS ALONG WITH ANY LINGERING EFFECTS FROM POSSIBLE MCS DEVELOPMENT WED NIGHT. THERE COULD ACTUALLY BE A SUBSTANTIAL TEMP GRADIENT FROM SW-NE ACROSS THE FCST AREA. WHILE AREAS FROM ORD- GREELEY-FULLERTON MAY BE JAMMED IN THE 70S...AREAS FROM BEAVER CITY- OSBORNE KS MAY BE IN THE UPPER 90S. FRI: ANOTHER THRUST OF BIG TIME HEAT IN THE WARM SECTOR. BELIEVE ODDS FAVOR 95-105F. LOOK FOR THIS TIME FRAME TO TREND HIGHER. FRI NIGHT OR SAT: POSSIBLY A COOL FRONTAL PASSAGE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1237 AM CDT SUN JUL 6 2014 VFR CONDITIONS IN THE FORECAST FOR THIS TAF PERIOD...WITH THE MAIN CONCERN LYING WITH THE PASSAGE OF A SURFACE COLD FRONT. WEAK SFC PATTERN CURRENTLY IN PLACE WILL KEEP WINDS LIGHT AND VARIABLE AS WE GET PAST SUNRISE...WITH WINDS THEN STARTING TO SWITCH TO THE NW THEN N WITH TIME. EVEN WITH THE BOUNDARY PASSING THROUGH...SPEEDS ARE NOT EXPECTED TO TOP 10 TO 15 MPH. MODELS SUGGEST THE POTENTIAL FOR THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON/EVENING...BUT CONFIDENCE IN ITS IMPACT ON THE TERMINAL AREAS LOW ENOUGH NOT TO INSERT ANY MENTION AT THIS POINT. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...JCB LONG TERM...HALBLAUB AVIATION...ADO
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
518 AM EDT SUN JUL 6 2014 .SYNOPSIS... MID AND HIGH LEVEL CLOUDS WILL MOVE ACROSS THE AREA TODAY ALTHOUGH RAIN CHANCES WILL BE MINIMAL. MORE TYPICAL SUMMERTIME WEATHER WILL DEVELOP MONDAY THROUGH WEDNESDAY ALTHOUGH THUNDERSTORM CHANCES WILL REMAIN QUITE LOW. RAIN CHANCES INCREASE INTO LATE WEEK THROUGH NEXT WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 345 AM SUNDAY...MODELS IDENTIFY THE WEAK LOW-MID LEVEL S/W TROF OR VORT MAX OFF THE FL-GA COASTS THIS MORNING...AND LIFT IT TO THE N-NE...MORE OR LESS PARALLEL TO THE SE U.S. COASTLINE...TO THE NC ATL WATERS NC BETWEEN CAPE LOOKOUT AND CAPE FEAR AROUND DAYBREAK MONDAY. THE MAIN PROBLEM FOR THIS NEAR TERM PERIOD WILL BE HOW FAR INLAND WILL THE ASSOCIATED MOISTURE...IE. CLOUDS AND PCPN...EXTEND. THE NAM SEEMS MUCH MORE WETTER THAN THE GFS...ALONG WITH A FURTHER EXTENSION INLAND WITH ITS POPS...IE LOOK AT THE LATEST NAM MOS GUIDANCE. HOWEVER...THE CURRENT CLOUD FIELD SHOWS MAINLY A THIN/OPAQUE CI SHIELD ACROSS THE FA WITH POSSIBLE LOW-MID CLOUDS ACROSS THE SOUTHERN PORTIONS OF GEORGETOWN COUNTY VIA LATEST 11-3.9 MICRON SAT IMAGERY. WILL LEAN TOWARD THE GFS MOS POP OUTPUT...WITH A LESS EXTENSION INLAND WITH POPS AND ALSO WITH THE LOW- MID LEVEL CLOUDS. IN ESSENCE...WILL GO WITH A MAX OF 20-40 POPS ACROSS THE IMMEDIATE COAST AS THIS DISTURBANCE FEATURE ALOFT MAKES ITS WAY TO THE N-NE. NOT ONE OF YOUR BETTER BEACH DAYS WITH THIN-OPAQUE HIGH LEVEL CLOUDINESS OCCURRING...AND WITH INCREASING LOW-MID LEVEL CLOUD DECKS DURING THE DAY. MAX TEMPS OF WIDESPREAD 80S TO OCCUR ACROSS THE ENTIRE FA...WITH THE OPAQUE CI/CS AND ADDITIONAL LOW- MID LEVEL CLOUDS KEEPING MAXES NEARLY A CATEGORY LOWER...IE. THE IMMEDIATE COAST. TONIGHTS MIN TEMPS IN THE MID TO UPPER 60S...70-75 ALONG THE IMMEDIATE COAST DUE TO ONSHORE FLOW ACROSS SSTS AROUND 80. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 AM SUNDAY...MID LEVEL SYSTEM THAT WILL PROVIDE CLOUDINESS TODAY WILL MOVE OFF TO THE NORTHEAST MONDAY. NVA IN THE WAKE OF THIS SYSTEM SHOULD PRECLUDE ANY CONVECTION BUT THIS TIME OF YEAR WITH STRONG DAYTIME HEATING ITS TOUGH TO KEEP THE FORECAST ENTIRELY DRY. WE ARE STILL ADVERTISING POPS FOR MONDAY WITH TUESDAY DRY. TEMPERATURE FORECAST REMAINS STABLE WITH A FEW DEGREES TACKED ON TO THE 88-93 RANGE MONDAY FOR TUESDAY. OVERNIGHT LOWS IN THE 60S WILL BE HISTORY WITH LOWER TO MIDDLE 70S AREA WIDE. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 330 AM SUNDAY...OVERALL THE MID LEVEL PATTERN HAS TRENDED SLIGHTLY TOWARD A BIT MORE OF AN ELONGATED RIDGE LATER IN THE PERIOD ALTHOUGH THIS APPEARS TO HAVE LITTLE IMPACT ON THE SENSIBLE WEATHER ELEMENTS FOR OUR LOCAL AREA. THE TROUGH ACROSS THE MIDWEST WEAKENS MORESO INSTEAD OF MOVING EAST AND THIS KEEPS THE ASSOCIATED FRONTS FROM PASSING ACROSS THE AREA. THE LATEST WPC GRAPHICS SHOW A FRONT ACROSS THE AREA EARLY SATURDAY WHICH WILL REMAIN THE CATALYST FOR GOOD CHANCES OF SHOWERS THEN DISSIPATING BY THE NEW DAY SUNDAY. FRIDAY REMAINS ON TRACK FOR GOOD COVERAGE OF CONVECTION AS WELL. WEDNESDAY AND THURSDAY WILL SEE ISOLATED TO CHANCE COVERAGE. NO CHANGES TO THE PREVIOUS TEMPERATURE FORECAST. && .AVIATION /09Z SUNDAY THROUGH THURSDAY/... AS OF 06Z...EXPECT VFR CONDITIONS TO PERSIST THROUGH THE TAF PERIOD. SURFACE OBS AND LATEST SAT IMAGERY ACROSS SOUTH CAROLINA SUGGEST SOME 3-4KFT CLOUDS ARE MAKING THEIR WAY ONSHORE KMYR/KCRE...BUT CIGS SHOULD REMAIN VFR OVERNIGHT VIA LATEST MODEL RUNS. HAVE INTRODUCED VCSH FOR KMYR/KCRE LATER TODAY AS AN UPPER DISTURBANCE OFF THE GA/SC COAST LIFTS NORTHWARD. DO NOT EXPECT MORE THAN TEMPO -SHRA/MVFR AT WORST...BUT COVERAGE WILL BE SO ISOLATED THAT THESE TERMS MAY NOT SEE ANY PCPN AT ALL. THE OTHER TAF SITES LOOK TO REMAIN DRY TODAY AS THE BULK OF THE PCPN WILL REMAIN OFFSHORE. EAST WINDS AROUND 5 KTS THIS MORNING WILL BECOME SOUTHEAST 10-15 KT AT THE COAST...5 TO 10 KT INLAND AFTER 17Z AS HIGH PRESSURE MOVES FURTHER OFF THE ATLANTIC COAST. VFR WILL CONTINUE INTO THE EVENING HOURS AS WINDS BECOME LIGHT/VRB. EXTENDED OUTLOOK...VFR WILL PREVAIL THROUGH THE EXTENDED PERIOD. SLIGHT CHANCE OF SHOWERS/TSTMS WEDNESDAY AND THURSDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1030 PM SATURDAY...THE LIMITED MARINE DATA AVAILABLE CONFIRMS OUR EARLIER FORECAST AND NO SIGNIFICANT CHANGES ARE NEEDED TO WINDS OR SEAS. THE NEW 00Z NAM MODEL PLUS SEVERAL OF THE RECENT RUNS OF THE HRRR MODEL SUGGEST THE POTENTIAL FOR SHOWERS AROUND SUNRISE MAY BE RISING IN THE GEORGETOWN/WINYAH BAY VICINITY AND OFFSHORE. ALSO OF NOTE OUR LOCAL WATERSPOUT THREAT CALCULATOR HAS INCREASED THAT POTENTIAL INTO THE "MODERATE" CATEGORY FOR SUNDAY. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS... 1024 MB HIGH PRESSURE CENTERED OVER WESTERN VIRGINIA IS PRODUCING AN ONSHORE WIND ACROSS MOST OF THE COASTAL SOUTHEAST THIS EVENING. A WEAK AREA OF LOW PRESSURE ASSOCIATED WITH AN ODD MID AND UPPER-LEVEL DISTURBANCE ALONG THE GEORGIA COAST IS HELPING ACCELERATE THE ONSHORE WINDS WITH SUSTAINED SPEEDS AS HIGH AS 20 KNOTS BEING REPORTED NEARSHORE FROM MYRTLE BEACH SOUTHWARD INTO THE CHARLESTON VICINITY. THESE WIND SPEEDS SHOULD GRADUALLY DIMINISH OVERNIGHT...ESPECIALLY ACROSS THE NC WATERS WHERE THE HIGH WILL BUILD DOWN AND SPREAD ITS LESSENED PRESSURE GRADIENT OVERHEAD. A LITTLE TIGHTER PRESSURE GRADIENT SHOULD CONTINUE OVER THE SOUTH CAROLINA WATERS AND THAT IS WHERE MY HIGHEST FORECAST WIND SPEEDS WILL REMAIN. AN EARLIER UPDATE LATE THIS AFTERNOON BROUGHT NEARSHORE SEAS INTO ALIGNMENT WITH THE ONSHORE WINDS...AND NO FURTHER SIGNIFICANT CHANGES ARE NEEDED. THE NEARSHORE WRIGHTSVILLE BEACH BUOY IS REPORTING A 3.4 FT CHOP EVERY 5 SECONDS...WITH NOAA BUOY 41004 40 MILES SOUTHEAST OF CHARLESTON REPORTING A VERY CHOPPY 7 FEET EVERY 5-6 SECONDS. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 330 AM SUNDAY...A FAIRLY BRISK SOUTHWEST FLOW OF 15-20 KNOTS WILL PREVAIL ACROSS THE WATERS THROUGH THE PERIOD. THE FLOW MAY DIP BELOW 15 KNOTS BRIEFLY BUT OVERALL THIS RANGE SHOULD SUFFICE. THE PRIMARY REASON IS THE DEVELOPMENT OF THE PIEDMONT TROUGH. SEAS SHOULD REMAIN CONFINED TO A 2-4 FOOT RANGE. LONG TERM /TUESDAY THROUGH THURSDAY/... AS OF 330 AM SUNDAY...SOUTH TO SOUTHWEST WINDS WILL PREVAIL ACROSS THE COASTAL WATERS WITH THE STRONGEST WINDS OCCURRING WEDNESDAY. THESE SPEEDS WILL BE 15-20 KNOTS AS A FRONT SLOWLY APPROACHES FROM THE NORTHWEST THUS INCREASING THE GRADIENT. A GRADUAL WEAKENING OF THE FRONT AND SUBSEQUENT SPEEDS OCCUR THURSDAY. SIGNIFICANT SEAS WILL BE HIGHER WEDNESDAY WITH 2-4 FEET DROPPING OT 2-3 FEET THURSDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...SHK NEAR TERM...DCH SHORT TERM...SHK LONG TERM...SHK AVIATION...DCH/BJR MARINE...
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
329 AM EDT SUN JUL 6 2014 .SYNOPSIS... MID AND HIGH LEVEL CLOUDS WILL MOVE ACROSS THE AREA TODAY ALTHOUGH RAIN CHANCES WILL BE MINIMAL. MORE TYPICAL SUMMERTIME WEATHER WILL DEVELOP MONDAY THROUGH WEDNESDAY ALTHOUGH THUNDERSTORM CHANCES WILL REMAIN QUITE LOW. RAIN CHANCES INCREASE INTO LATE WEEK THROUGH NEXT WEEKEND. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1030 PM SATURDAY...MAINLY THIN CIRRUS IS STREAMING OVERHEAD THIS EVENING...BUT THE INFRARED SATELLITE PRESENTATION IS QUITE A BIT WORSE THAN IT LOOKS FROM THE OFFICE PARKING LOT. THE ONLY LOCATION IN OUR FORECAST AREA WITH LOWER CLOUDS BENEATH THE CIRRUS IS GEORGETOWN WHERE CLOUDS WITH BASES JUST ABOVE 3000 FEET (PRESUMABLY MARITIME CUMULUS) ARE BEING REPORTED ON THE GGE AWOS. THE NEW 00Z NAM CONCURS WITH RECENT HRRR RUNS THAT MARINE SHOWERS MAY ATTEMPT TO SPREAD ONSHORE IN THE GEORGETOWN VICINITY AROUND SUNRISE...SO I HAVE UPPED POPS SLIGHTLY IN THE 11-15Z TIME FRAME THERE. OTHERWISE NO SIGNIFICANT CHANGES ARE NEEDED TO THE FORECAST. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS... HIGH PRESSURE OVER WESTERN VIRGINIA WILL BUILD SOUTHEASTWARD OVERNIGHT...SETTLING ACROSS EASTERN NORTH CAROLINA BEFORE DAYBREAK. TO THE SOUTH A SEEMINGLY OUT-OF-PLACE UPPER LEVEL DISTURBANCE OFF THE GEORGIA COAST IS IGNITING QUITE A BIT OF THUNDERSTORM ACTIVITY FROM SOUTHERN SOUTH CAROLINA TO THE FLORIDA EAST COAST. CONVECTIVE BLOWOFF CLOUDINESS STREAMING NORTHWARD HAS PROVIDED A BIT MORE CLOUD COVER THAN EARLIER ANTICIPATED ACROSS NORTHEASTERN SOUTH CAROLINA INCLUDING GEORGETOWN AND MYRTLE BEACH. WHILE MUCH OF THE LOWER CUMULUS CLOUD COVER THAT DEVELOPED DURING THE HEAT OF THE AFTERNOON WILL DISSIPATE THIS EVENING...THIS HIGHER CONVECTIVE BLOWOFF MAY PERSIST. AS THE WEAK UPPER DISTURBANCE DRIFTS NORTHWARD...ATLANTIC MOISTURE WILL INCREASE ALONG THE BASE OF A SIGNIFICANT SUBSIDENCE INVERSION BETWEEN 775-700 MB...APPROXIMATELY 7500-10500 FEET ABOVE GROUND LEVEL. THIS MAY SPELL INCREASING CLOUD COVER AFTER MIDNIGHT ESPECIALLY ACROSS NORTHEASTERN SOUTH CAROLINA WHERE CONDITIONS MAY TEMPORARILY CLEAR OUT LATER THIS EVENING. WITH FAIRLY STEEP LAPSE RATES BENEATH THE SUBSIDENCE INVERSION IT IS EVEN POSSIBLE NOCTURNAL MARINE CONVECTION DEVELOPING OVER THE SHALLOW INSTABILITY OFFSHORE WILL ADVECT WESTWARD...WITH SHOWER CHANCES DEVELOPING ALONG THE SC COAST SOUTH OF MYRTLE BEACH. LOW TEMPERATURES WILL HAVE A PRONOUNCED NORTH-SOUTH GRADIENT TONIGHT. ACROSS INTERIOR SE NORTH CAROLINA GOOD RADIATIONAL COOLING AND A PREEXISTING COOL/DRY AIRMASS SHOULD ALLOW TEMPERATURES TO FALL INTO 61-65 RANGE...IN PLACES ALMOST 10 DEGREES BELOW NORMAL. ACROSS NE SOUTH CAROLINA MORE CLOUDS AND A HEALTHIER ONSHORE WIND WILL PRECLUDE EFFICIENT RADIATIONAL COOLING WITH LOWS GENERALLY IN THE UPPER 60S TO AROUND 70...WARMEST NEAR THE COAST. && .SHORT TERM /MONDAY THROUGH TUESDAY/... AS OF 300 AM SUNDAY...MID LEVEL SYSTEM THAT WILL PROVIDE CLOUDINESS TODAY WILL MOVE OFF TO THE NORTHEAST MONDAY. NVA IN THE WAKE OF THIS SYSTEM SHOULD PRECLUDE ANY CONVECTION BUT THIS TIME OF YEAR WITH STRONG DAYTIME HEATING ITS TOUGH TO KEEP THE FORECAST ENTIRELY DRY. WE ARE STILL ADVERTISING POPS FOR MONDAY WITH TUESDAY DRY. TEMPERATURE FORECAST REMAINS STABLE WITH A FEW DEGREES TACKED ON TO THE 88-93 RANGE MONDAY FOR TUESDAY. OVERNIGHT LOWS IN THE 60S WILL BE HISTORY WITH LOWER TO MIDDLE 70S AREA WIDE. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 330 AM SUNDAY...OVERALL THE MID LEVEL PATTERN HAS TRENDED SLIGHTLY TOWARD A BIT MORE OF AN ELONGATED RIDGE LATER IN THE PERIOD ALTHOUGH THIS APPEARS TO HAVE LITTLE IMPACT ON THE SENSIBLE WEATHER ELEMENTS FOR OUR LOCAL AREA. THE TROUGH ACROSS THE MIDWEST WEAKENS MORESO INSTEAD OF MOVING EAST AND THIS KEEPS THE ASSOCIATED FRONTS FROM PASSING ACROSS THE AREA. THE LATEST WPC GRAPHICS SHOW A FRONT ACROSS THE AREA EARLY SATURDAY WHICH WILL REMAIN THE CATALYST FOR GOOD CHANCES OF SHOWERS THEN DISSIPATING BY THE NEW DAY SUNDAY. FRIDAY REMAINS ON TRACK FOR GOOD COVERAGE OF CONVECTION AS WELL. WEDNESDAY AND THURSDAY WILL SEE ISOLATED TO CHANCE COVERAGE. NO CHANGES TO THE PREVIOUS TEMPERATURE FORECAST. && .AVIATION /07Z SUNDAY THROUGH THURSDAY/... AS OF 06Z...EXPECT VFR CONDITIONS TO PERSIST THROUGH THE TAF PERIOD. SURFACE OBS AND LATEST SAT IMAGERY ACROSS SOUTH CAROLINA SUGGEST SOME 3-4KFT CLOUDS ARE MAKING THEIR WAY ONSHORE KMYR/KCRE...BUT CIGS SHOULD REMAIN VFR OVERNIGHT VIA LATEST MODEL RUNS. HAVE INTRODUCED VCSH FOR KMYR/KCRE LATER TODAY AS AN UPPER DISTURBANCE OFF THE GA/SC COAST LIFTS NORTHWARD. DO NOT EXPECT MORE THAN TEMPO -SHRA/MVFR AT WORST...BUT COVERAGE WILL BE SO ISOLATED THAT THESE TERMS MAY NOT SEE ANY PCPN AT ALL. THE OTHER TAF SITES LOOK TO REMAIN DRY TODAY AS THE BULK OF THE PCPN WILL REMAIN OFFSHORE. EAST WINDS AROUND 5 KTS THIS MORNING WILL BECOME SOUTHEAST 10-15 KT AT THE COAST...5 TO 10 KT INLAND AFTER 17Z AS HIGH PRESSURE MOVES FURTHER OFF THE ATLANTIC COAST. VFR WILL CONTINUE INTO THE EVENING HOURS AS WINDS BECOME LIGHT/VRB. EXTENDED OUTLOOK...VFR WILL PREVAIL THROUGH THE EXTENDED PERIOD. SLIGHT CHANCE OF SHOWERS/TSTMS WEDNESDAY AND THURSDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1030 PM SATURDAY...THE LIMITED MARINE DATA AVAILABLE CONFIRMS OUR EARLIER FORECAST AND NO SIGNIFICANT CHANGES ARE NEEDED TO WINDS OR SEAS. THE NEW 00Z NAM MODEL PLUS SEVERAL OF THE RECENT RUNS OF THE HRRR MODEL SUGGEST THE POTENTIAL FOR SHOWERS AROUND SUNRISE MAY BE RISING IN THE GEORGETOWN/WINYAH BAY VICINITY AND OFFSHORE. ALSO OF NOTE OUR LOCAL WATERSPOUT THREAT CALCULATOR HAS INCREASED THAT POTENTIAL INTO THE "MODERATE" CATEGORY FOR SUNDAY. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS... 1024 MB HIGH PRESSURE CENTERED OVER WESTERN VIRGINIA IS PRODUCING AN ONSHORE WIND ACROSS MOST OF THE COASTAL SOUTHEAST THIS EVENING. A WEAK AREA OF LOW PRESSURE ASSOCIATED WITH AN ODD MID AND UPPER-LEVEL DISTURBANCE ALONG THE GEORGIA COAST IS HELPING ACCELERATE THE ONSHORE WINDS WITH SUSTAINED SPEEDS AS HIGH AS 20 KNOTS BEING REPORTED NEARSHORE FROM MYRTLE BEACH SOUTHWARD INTO THE CHARLESTON VICINITY. THESE WIND SPEEDS SHOULD GRADUALLY DIMINISH OVERNIGHT...ESPECIALLY ACROSS THE NC WATERS WHERE THE HIGH WILL BUILD DOWN AND SPREAD ITS LESSENED PRESSURE GRADIENT OVERHEAD. A LITTLE TIGHTER PRESSURE GRADIENT SHOULD CONTINUE OVER THE SOUTH CAROLINA WATERS AND THAT IS WHERE MY HIGHEST FORECAST WIND SPEEDS WILL REMAIN. AN EARLIER UPDATE LATE THIS AFTERNOON BROUGHT NEARSHORE SEAS INTO ALIGNMENT WITH THE ONSHORE WINDS...AND NO FURTHER SIGNIFICANT CHANGES ARE NEEDED. THE NEARSHORE WRIGHTSVILLE BEACH BUOY IS REPORTING A 3.4 FT CHOP EVERY 5 SECONDS...WITH NOAA BUOY 41004 40 MILES SOUTHEAST OF CHARLESTON REPORTING A VERY CHOPPY 7 FEET EVERY 5-6 SECONDS. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 330 AM SUNDAY...A FAIRLY BRISK SOUTHWEST FLOW OF 15-20 KNOTS WILL PREVAIL ACROSS THE WATERS THROUGH THE PERIOD. THE FLOW MAY DIP BELOW 15 KNOTS BRIEFLY BUT OVERALL THIS RANGE SHOULD SUFFICE. THE PRIMARY REASON IS THE DEVELOPMENT OF THE PIEDMONT TROUGH. SEAS SHOULD REMAIN CONFINED TO A 2-4 FOOT RANGE. LONG TERM /TUESDAY THROUGH THURSDAY/... AS OF 330 AM SUNDAY...SOUTH TO SOUTHWEST WINDS WILL PREVAIL ACROSS THE COASTAL WATERS WITH THE STRONGEST WINDS OCCURRING WEDNESDAY. THESE SPEEDS WILL BE 15-20 KNOTS AS A FRONT SLOWLY APPROACHES FROM THE NORTHWEST THUS INCREASING THE GRADIENT. A GRADUAL WEAKENING OF THE FRONT AND SUBSEQUENT SPEEDS OCCUR THURSDAY. SIGNIFICANT SEAS WILL BE HIGHER WEDNESDAY WITH 2-4 FEET DROPPING OT 2-3 FEET THURSDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...SHK NEAR TERM...TRA SHORT TERM...SHK LONG TERM...SHK AVIATION...DCH/BJR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
143 AM EDT SUN JUL 6 2014 .SYNOPSIS... DRIER THAN NORMAL CONDITIONS AND FAIR WEATHER CAN BE EXPECTED THROUGH SUNDAY AS CANADIAN HIGH PRESSURE SETTLES OVER THE AREA. THE HIGH WILL MOVE OFFSHORE AND ANCHOR OVER THE WESTERN ATLANTIC ALLOWING HEAT AND HUMIDITY TO RETURN MUCH OF THE UPCOMING WEEK. GRADUALLY DEEPENING LOW PRESSURE ALONG THE PIEDMONT AND SANDHILLS OF THE CAROLINAS...WILL LED TO AN INCREASE IN THUNDERSTORMS THROUGH THE WEEK...MAINLY DURING THE AFTERNOONS AND EVENINGS. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1030 PM SATURDAY...MAINLY THIN CIRRUS IS STREAMING OVERHEAD THIS EVENING...BUT THE INFRARED SATELLITE PRESENTATION IS QUITE A BIT WORSE THAN IT LOOKS FROM THE OFFICE PARKING LOT. THE ONLY LOCATION IN OUR FORECAST AREA WITH LOWER CLOUDS BENEATH THE CIRRUS IS GEORGETOWN WHERE CLOUDS WITH BASES JUST ABOVE 3000 FEET (PRESUMABLY MARITIME CUMULUS) ARE BEING REPORTED ON THE GGE AWOS. THE NEW 00Z NAM CONCURS WITH RECENT HRRR RUNS THAT MARINE SHOWERS MAY ATTEMPT TO SPREAD ONSHORE IN THE GEORGETOWN VICINITY AROUND SUNRISE...SO I HAVE UPPED POPS SLIGHTLY IN THE 11-15Z TIME FRAME THERE. OTHERWISE NO SIGNIFICANT CHANGES ARE NEEDED TO THE FORECAST. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS... HIGH PRESSURE OVER WESTERN VIRGINIA WILL BUILD SOUTHEASTWARD OVERNIGHT...SETTLING ACROSS EASTERN NORTH CAROLINA BEFORE DAYBREAK. TO THE SOUTH A SEEMINGLY OUT-OF-PLACE UPPER LEVEL DISTURBANCE OFF THE GEORGIA COAST IS IGNITING QUITE A BIT OF THUNDERSTORM ACTIVITY FROM SOUTHERN SOUTH CAROLINA TO THE FLORIDA EAST COAST. CONVECTIVE BLOWOFF CLOUDINESS STREAMING NORTHWARD HAS PROVIDED A BIT MORE CLOUD COVER THAN EARLIER ANTICIPATED ACROSS NORTHEASTERN SOUTH CAROLINA INCLUDING GEORGETOWN AND MYRTLE BEACH. WHILE MUCH OF THE LOWER CUMULUS CLOUD COVER THAT DEVELOPED DURING THE HEAT OF THE AFTERNOON WILL DISSIPATE THIS EVENING...THIS HIGHER CONVECTIVE BLOWOFF MAY PERSIST. AS THE WEAK UPPER DISTURBANCE DRIFTS NORTHWARD...ATLANTIC MOISTURE WILL INCREASE ALONG THE BASE OF A SIGNIFICANT SUBSIDENCE INVERSION BETWEEN 775-700 MB...APPROXIMATELY 7500-10500 FEET ABOVE GROUND LEVEL. THIS MAY SPELL INCREASING CLOUD COVER AFTER MIDNIGHT ESPECIALLY ACROSS NORTHEASTERN SOUTH CAROLINA WHERE CONDITIONS MAY TEMPORARILY CLEAR OUT LATER THIS EVENING. WITH FAIRLY STEEP LAPSE RATES BENEATH THE SUBSIDENCE INVERSION IT IS EVEN POSSIBLE NOCTURNAL MARINE CONVECTION DEVELOPING OVER THE SHALLOW INSTABILITY OFFSHORE WILL ADVECT WESTWARD...WITH SHOWER CHANCES DEVELOPING ALONG THE SC COAST SOUTH OF MYRTLE BEACH. LOW TEMPERATURES WILL HAVE A PRONOUNCED NORTH-SOUTH GRADIENT TONIGHT. ACROSS INTERIOR SE NORTH CAROLINA GOOD RADIATIONAL COOLING AND A PREEXISTING COOL/DRY AIRMASS SHOULD ALLOW TEMPERATURES TO FALL INTO 61-65 RANGE...IN PLACES ALMOST 10 DEGREES BELOW NORMAL. ACROSS NE SOUTH CAROLINA MORE CLOUDS AND A HEALTHIER ONSHORE WIND WILL PRECLUDE EFFICIENT RADIATIONAL COOLING WITH LOWS GENERALLY IN THE UPPER 60S TO AROUND 70...WARMEST NEAR THE COAST. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/... AS OF 320 PM SATURDAY...ANOTHER DAY WITH RELATIVELY LOW HUMIDITY WILL PREVAIL SUNDAY BEFORE THE CANADIAN HIGH MIGRATES OFFSHORE SUNDAY NIGHT AND INCREASING SOUTHERLY FLOW BEGINS TO DEVELOP INTO MONDAY. MONDAY WILL BE A WARMER AND MORE HUMID DAY THAN SUNDAY DUE TO VEERING WINDS AND THE USHERING OF A MORE TYPICAL SUMMER TIME AIR-MASS INTO THE CAROLINAS. ON AVERAGE MAXIMUM TEMPS MONDAY LOOKS TO PAN OUT 4-7 DEGREES WARMER THAN SUNDAY. AN UPPER DISTURBANCE IN VICINITY OF A STALLED FRONTAL BOUNDARY OVER GA/SC MAY PRODUCE A FEW SHOWERS OVER OUR VERY SOUTHERN COAST AND COASTAL INTERIOR TO NEAR CAPE FEAR SUNDAY. DRY AIR ALOFT OVER THE REGION WILL SIGNIFICANTLY LIMIT THE EXTENT OF EXPECTED PCPN AND CELL COVERAGE...AND ONLY ISOLATED POP VALUES WILL BE ADVERTISED FOR THE SC ZONES. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... AS OF 320 PM SATURDAY...ANTICIPATE A FAIRLY DRY AND QUIET START TO THE PERIOD AS A WEAK UPPER LEVEL PATTERN REMAINS IN PLACE FOR TUESDAY INTO EARLY WEDNESDAY...WITH HIGHS ON BOTH DAYS IN THE MID TO UPPER 90S INLAND/LOWER 90S ALONG THE COAST WITH THE AFTERNOON SEA BREEZE...AND OVERNIGHT LOWS IN THE LOW TO MID 70S. PATTERN BEGINS TO CHANGE WEDNESDAY INTO THURSDAY AS AN UPPER LEVEL TROUGH BEGINS TO DIG SOUTH ACROSS THE EASTERN US WITH AN ASSOCIATED COLD FRONT SLOWLY PROGRESSING TOWARDS THE CAROLINAS WITH THE AID OF A HIGH PRESSURE WELL TO THE NORTHWEST . TRICKY PART OF THE FORECAST WILL BE THE PROGRESSION OF THE FRONT AND WHETHER IT STALLS AND FIZZLES WEST OF THE FORECAST AREA...OR IF IT REACHES THE FORECAST AREA AND STALLS. OVERALL...HAVE DECIDED TO KEEP WITH A NON-FRONTAL PASSAGE EVENT...BUT RATHER HAVING IT STALL/FALL JUST SHORT TO OUR WEST. WITH THAT SAID...HAVE SLIGHTLY INCREASED CLOUD COVER/POPS AND KEPT INCREASING CHANCES FOR ISOLATED TO SCATTERED THUNDERSTORMS THROUGH THE REST OF THE WEEK ACROSS THE ENTIRE FORECAST AREA AS MOISTURE INCREASES...WITH PRECIPITABLE WATER VALUES NEARING 2 INCHES OR SLIGHTLY MORE. AS FOR TEMPS WE WILL COOL DOWN SLIGHTLY ON FRIDAY AND SATURDAY WITH HIGHS IN THE UPPER 80S/LOWER 90S AND OVERNIGHT LOWS IN THE LOWER 70S. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... AS OF 06Z...EXPECT VFR CONDITIONS TO PERSIST THROUGH THE TAF PERIOD. SURFACE OBS AND LATEST SAT IMAGERY ACROSS SOUTH CAROLINA SUGGEST SOME 3-4KFT CLOUDS ARE MAKING THEIR WAY ONSHORE KMYR/KCRE...BUT CIGS SHOULD REMAIN VFR OVERNIGHT VIA LATEST MODEL RUNS. HAVE INTRODUCED VCSH FOR KMYR/KCRE LATER TODAY AS AN UPPER DISTURBANCE OFF THE GA/SC COAST LIFTS NORTHWARD. DO NOT EXPECT MORE THAN TEMPO -SHRA/MVFR AT WORST...BUT COVERAGE WILL BE SO ISOLATED THAT THESE TERMS MAY NOT SEE ANY PCPN AT ALL. THE OTHER TAF SITES LOOK TO REMAIN DRY TODAY AS THE BULK OF THE PCPN WILL REMAIN OFFSHORE. EAST WINDS AROUND 5 KTS THIS MORNING WILL BECOME SOUTHEAST 10-15 KT AT THE COAST...5 TO 10 KT INLAND AFTER 17Z AS HIGH PRESSURE MOVES FURTHER OFF THE ATLANTIC COAST. VFR WILL CONTINUE INTO THE EVENING HOURS AS WINDS BECOME LIGHT/VRB. EXTENDED OUTLOOK...VFR WILL PREVAIL THROUGH THE EXTENDED PERIOD. SLIGHT CHANCE OF SHOWERS/TSTMS WEDNESDAY AND THURSDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1030 PM SATURDAY...THE LIMITED MARINE DATA AVAILABLE CONFIRMS OUR EARLIER FORECAST AND NO SIGNIFICANT CHANGES ARE NEEDED TO WINDS OR SEAS. THE NEW 00Z NAM MODEL PLUS SEVERAL OF THE RECENT RUNS OF THE HRRR MODEL SUGGEST THE POTENTIAL FOR SHOWERS AROUND SUNRISE MAY BE RISING IN THE GEORGETOWN/WINYAH BAY VICINITY AND OFFSHORE. ALSO OF NOTE OUR LOCAL WATERSPOUT THREAT CALCULATOR HAS INCREASED THAT POTENTIAL INTO THE "MODERATE" CATEGORY FOR SUNDAY. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS... 1024 MB HIGH PRESSURE CENTERED OVER WESTERN VIRGINIA IS PRODUCING AN ONSHORE WIND ACROSS MOST OF THE COASTAL SOUTHEAST THIS EVENING. A WEAK AREA OF LOW PRESSURE ASSOCIATED WITH AN ODD MID AND UPPER-LEVEL DISTURBANCE ALONG THE GEORGIA COAST IS HELPING ACCELERATE THE ONSHORE WINDS WITH SUSTAINED SPEEDS AS HIGH AS 20 KNOTS BEING REPORTED NEARSHORE FROM MYRTLE BEACH SOUTHWARD INTO THE CHARLESTON VICINITY. THESE WIND SPEEDS SHOULD GRADUALLY DIMINISH OVERNIGHT...ESPECIALLY ACROSS THE NC WATERS WHERE THE HIGH WILL BUILD DOWN AND SPREAD ITS LESSENED PRESSURE GRADIENT OVERHEAD. A LITTLE TIGHTER PRESSURE GRADIENT SHOULD CONTINUE OVER THE SOUTH CAROLINA WATERS AND THAT IS WHERE MY HIGHEST FORECAST WIND SPEEDS WILL REMAIN. AN EARLIER UPDATE LATE THIS AFTERNOON BROUGHT NEARSHORE SEAS INTO ALIGNMENT WITH THE ONSHORE WINDS...AND NO FURTHER SIGNIFICANT CHANGES ARE NEEDED. THE NEARSHORE WRIGHTSVILLE BEACH BUOY IS REPORTING A 3.4 FT CHOP EVERY 5 SECONDS...WITH NOAA BUOY 41004 40 MILES SOUTHEAST OF CHARLESTON REPORTING A VERY CHOPPY 7 FEET EVERY 5-6 SECONDS. SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 320 PM SATURDAY...ONSHORE ENE-E WINDS SUNDAY MORNING WILL RESULT IN BUMPY 3-4 FOOT SEAS FOR THE MOST PART...BUT AS WINDS GO SE AND S INTO AFTERNOON AND EVENING...SEAS WILL LIKELY DROP ANOTHER FOOT OR SO. SO WHILE NOT IDEAL CONDITIONS...NO ADVISORIES OR EXERCISE CAUTION STATEMENTS WILL BE NEEDED. NO TSTMS EXPECTED ON THE 0-20NM WATERS BUT A FEW SHOWERS MAY DOT AREAS AROUND WINYAH BAY. THE MAJORITY OF WAVE ENERGY WILL BE ARRIVING FROM E AND SE AND A MODERATE CHOP FROM THE S-SW IS EXPECTED MONDAY NIGHT AS WINDS NEAR 20 KT. AN EXERCISE CAUTION STATEMENT IS POSSIBLE MONDAY NIGHT INTO EARLY TUESDAY. LONG TERM /TUESDAY THROUGH THURSDAY/... AS OF 320 PM SATURDAY...PERSISTENT SOUTHWEST FLOW WILL CONTINUE THROUGH THE PERIOD WITH SUSTAINED WINDS OF 10 TO 15 KTS AND GUSTS TO NEAR 20 KTS DURING THE AFTERNOON HOURS EACH AFTERNOON. WITH MAINLY WIND DRIVEN WIND WAVES...TUESDAY AND WEDNESDAY SEAS WILL BE 2 TO 4 FT WITH 5 FTERS POSSIBLE IN THE EXTREME OUTER WATERS...ESPECIALLY IN AMZ-252 AND AMZ-250. INTO THURSDAY...SEAS WILL BEGIN TO SUBSIDE TO 2 TO 3 FT. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...MJC NEAR TERM...TRA SHORT TERM...MJC LONG TERM...SGL AVIATION...DCH/BJR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1155 PM CDT SAT JUL 5 2014 .UPDATE... ISSUED AT 1155 PM CDT SAT JUL 5 2014 IN COORDINATION WITH SPC...EXPANDED THE SEVERE THUNDERSTORM WATCH TO THE EAST. STORMS ALREADY GETTING TO THE END OF THE BOX AND ENVIRONMENTAL CONDITIONS ARE SIMILAR ACROSS THE EASTERN FA. UPDATE ISSUED AT 1145 PM CDT SAT JUL 5 2014 SEVERE THUNDERSTORMS ARE INCREASING IN COVERAGE AS EXPECTED...AND A SEVERE THUNDERSTORM WATCH WAS ISSUED AS A RESULT. MAY NEED TO EXTEND THE SEVERE THUNDERSTORM WATCH EASTWARD IF TREND CONTINUE. UPDATE ISSUED AT 942 PM CDT SAT JUL 5 2014 THE FIRST SEVERE THREAT IS NOW EAST OF THE FA. ATTENTION NOW TURNS TO THE WEST WITH STORMS APPROACHING FROM CANADA AND FROM SOUTHERN NORTH DAKOTA. THE HRRR/RAP MAY BE TOO WIDESPREAD WITH COVERAGE IN THEIR FORECASTS...BUT BOTH INDICATE THE POTENTIAL FOR STORMS TO FILL IN BETWEEN THESE TWO SEVERE AREAS...AND INDICATE THAT THESE STORMS HAVE THE POTENTIAL FOR BOWING SEGMENTS (STRONG WIND GUSTS). INSTABILITY REMAINS STRONG...AND DEEP LAYER SHEAR IS INCREASING...ALONG WITH A 40-50 KNOT MID-LEVEL SPEED MAX...AND WITH A STRONG UPPER WAVE (DECENT SYNOPTIC FORCING). SO...THE HI- RES MODELS MAY BE ONTO SOMETHING. THIS LOOKS TO BE A BUSY NIGHT. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 320 PM CDT SAT JUL 5 2014 CHALLENGES INCLUDE THUNDERSTORM CHANCES AND SEVERE POTENTIAL THIS EVENING AND OVERNIGHT. HRRR IS ONCE AGAIN PERFORMING MORE FAVORABLY THAN RAP AS IT RELATES TO CURRENT CONVECTION...SO WILL FOLLOW ITS GUIDANCE FOR THE FIRST 12 TO 18 HOURS AND THEN TRANSITION TO A GLOBAL MODEL ENSEMBLE. SFC TROUGH REFUSES TO BUDGE WITH A DEFINED CLOSED CIRCULATION NEAR THE ND/MN/MB BORDER. WINDS HAVE SHIFTED TO A MORE WESTERLY DIRECTION FROM DEVILS LAKE INTO THE JAMES RIVER VALLEY RESULTING IN A DRIER OVERALL AIR MASS...ALTHOUGH SFC BASED CAPE IS STILL ABOVE 2000 J/KG. BEST CHANCE FOR THUNDERSTORMS LATE THIS AFTERNOON IS ALONG THE INTERNATIONAL BORDER AREA OF NORTHWEST MN IN UNCAPPED MORE MOIST/UNSTABLE ENVIRONMENT NEAREST THE SFC LOW. FORCING IS STILL RATHER WEAK...BUT ONE SEVERE STORM HAS DEVELOPED OVER WINNIPEG AND IS SLOWLY MOVING TO THE EAST. A COUPLE OTHER SMALL CELLS HAVE POPPED UP ALONG THE SFC WIND SHIFT JUST NORTH OF THE BORDER AND IN KITTSON COUNTY. ISOLATED SEVERE IS POSSIBLE GIVEN HIGH INSTABILITY. REST OF THE FORECAST AREA WILL REMAIN DRY THIS EVENING WITH TEMPS GRADUALLY FALLING INTO THE UPPER 60S. FOR LATE TONIGHT INTO EARLY SUNDAY MORNING...ATTENTION TURNS TO THE SHORT-WAVE CURRENTLY ACROSS SOUTHERN ALBERTA. INCREASING SHEAR WILL BEGIN TO INTERACT WITH MUCAPES UP TO 1500 J/KG...POSSIBLY RESULTING IN A NORTH TO SOUTH LINE OF CONVECTION MOVING ACROSS THE DAKOTAS AND INTO NORTHWEST MN. HRRR PLACES THIS LINE ALONG THE VALLEY FLOOR BY 06 UTC. LARGE HAIL AND DAMAGING WIND WILL BE THE PRIMARY THREATS. SCATTERED SHOWERS AND STORMS ARE POSSIBLE MAINLY ACROSS NORTHWEST AND WEST CENTRAL MN ON SUNDAY...BUT TEMPS/DEW POINTS WILL BE LOWER RESULTING IN LESS MUGGY CONDITIONS. WINDS WILL ALSO BE BREEZY AT TIMES FROM THE NORTHWEST WITH GUSTS TO 25 MPH. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 320 PM CDT SAT JUL 5 2014 FLOW ALOFT SHIFTS TO THE NORTHWEST MON/TUES WITH THE NEXT PRIMARY WAVE DROPPING ACROSS THE NORTHERN PLAINS MONDAY/MONDAY NIGHT. SEVERE WEATHER NOT EXPECTED...BUT SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE THROUGH THE DAY ON MONDAY WITH DRYING CONDITIONS FROM WEST TO EAST ON TUESDAY. FOR TUESDAY NIGHT THROUGH SATURDAY...SOME DISAGREEMENT IN HOW DEEP NEXT 500 MB TROUGH WILL BE OVER ONTARIO AND GREAT LAKES REGION. EITHER WAY FCST REGION WILL BE IN NORTHWEST FLOW ALOFT WITH EXITING SHORT WAVE TUESDAY NIGHT THEN GENERAL HIGH PRESSURE FOR WED-EARLY THU. NEXT SIGNIFICANT SHORT WAVE TO IMPACT US LATE THU-FRI. DIDNT STRAY FROM ALL BLEND TEMPS NOR POPS MUCH. OVERALL TEMP REGIME AFTER THIS WEEKEND FAVORS A RETURN TO JUST A FEW DEGREES BELOW AVERAGE FOR HIGH TEMPS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1145 PM CDT SAT JUL 5 2014 THUNDERSTORM CHANCES WILL BE THE MAIN CONCERN THROUGH THIS PERIOD...ESPECIALLY BEFORE SUNRISE. THERE SHOULD BE A BROKEN LINE OF STORMS THAT MOVE FROM WEST TO EAST THROUGH THE REGION. NOT SURE HOW WIDESPREAD THESE STORMS WILL BE...BUT DID TEMPO FOR THE MOST LIKELY PERIODS. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...TG SHORT TERM...ROGERS LONG TERM...ROGERS/RIDDLE AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1145 PM CDT SAT JUL 5 2014 .UPDATE... ISSUED AT 1145 PM CDT SAT JUL 5 2014 SEVERE THUNDERSTORMS ARE INCREASING IN COVERAGE AS EXPECTED...AND A SEVERE THUNDERSTORM WATCH WAS ISSUED AS A RESULT. MAY NEED TO EXTEND THE SEVERE THUNDERSTORM WATCH EASTWARD IF TREND CONTINUE. UPDATE ISSUED AT 942 PM CDT SAT JUL 5 2014 THE FIRST SEVERE THREAT IS NOW EAST OF THE FA. ATTENTION NOW TURNS TO THE WEST WITH STORMS APPROACHING FROM CANADA AND FROM SOUTHERN NORTH DAKOTA. THE HRRR/RAP MAY BE TOO WIDESPREAD WITH COVERAGE IN THEIR FORECASTS...BUT BOTH INDICATE THE POTENTIAL FOR STORMS TO FILL IN BETWEEN THESE TWO SEVERE AREAS...AND INDICATE THAT THESE STORMS HAVE THE POTENTIAL FOR BOWING SEGMENTS (STRONG WIND GUSTS). INSTABILITY REMAINS STRONG...AND DEEP LAYER SHEAR IS INCREASING...ALONG WITH A 40-50 KNOT MID-LEVEL SPEED MAX...AND WITH A STRONG UPPER WAVE (DECENT SYNOPTIC FORCING). SO...THE HI- RES MODELS MAY BE ONTO SOMETHING. THIS LOOKS TO BE A BUSY NIGHT. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 320 PM CDT SAT JUL 5 2014 CHALLENGES INCLUDE THUNDERSTORM CHANCES AND SEVERE POTENTIAL THIS EVENING AND OVERNIGHT. HRRR IS ONCE AGAIN PERFORMING MORE FAVORABLY THAN RAP AS IT RELATES TO CURRENT CONVECTION...SO WILL FOLLOW ITS GUIDANCE FOR THE FIRST 12 TO 18 HOURS AND THEN TRANSITION TO A GLOBAL MODEL ENSEMBLE. SFC TROUGH REFUSES TO BUDGE WITH A DEFINED CLOSED CIRCULATION NEAR THE ND/MN/MB BORDER. WINDS HAVE SHIFTED TO A MORE WESTERLY DIRECTION FROM DEVILS LAKE INTO THE JAMES RIVER VALLEY RESULTING IN A DRIER OVERALL AIR MASS...ALTHOUGH SFC BASED CAPE IS STILL ABOVE 2000 J/KG. BEST CHANCE FOR THUNDERSTORMS LATE THIS AFTERNOON IS ALONG THE INTERNATIONAL BORDER AREA OF NORTHWEST MN IN UNCAPPED MORE MOIST/UNSTABLE ENVIRONMENT NEAREST THE SFC LOW. FORCING IS STILL RATHER WEAK...BUT ONE SEVERE STORM HAS DEVELOPED OVER WINNIPEG AND IS SLOWLY MOVING TO THE EAST. A COUPLE OTHER SMALL CELLS HAVE POPPED UP ALONG THE SFC WIND SHIFT JUST NORTH OF THE BORDER AND IN KITTSON COUNTY. ISOLATED SEVERE IS POSSIBLE GIVEN HIGH INSTABILITY. REST OF THE FORECAST AREA WILL REMAIN DRY THIS EVENING WITH TEMPS GRADUALLY FALLING INTO THE UPPER 60S. FOR LATE TONIGHT INTO EARLY SUNDAY MORNING...ATTENTION TURNS TO THE SHORT-WAVE CURRENTLY ACROSS SOUTHERN ALBERTA. INCREASING SHEAR WILL BEGIN TO INTERACT WITH MUCAPES UP TO 1500 J/KG...POSSIBLY RESULTING IN A NORTH TO SOUTH LINE OF CONVECTION MOVING ACROSS THE DAKOTAS AND INTO NORTHWEST MN. HRRR PLACES THIS LINE ALONG THE VALLEY FLOOR BY 06 UTC. LARGE HAIL AND DAMAGING WIND WILL BE THE PRIMARY THREATS. SCATTERED SHOWERS AND STORMS ARE POSSIBLE MAINLY ACROSS NORTHWEST AND WEST CENTRAL MN ON SUNDAY...BUT TEMPS/DEW POINTS WILL BE LOWER RESULTING IN LESS MUGGY CONDITIONS. WINDS WILL ALSO BE BREEZY AT TIMES FROM THE NORTHWEST WITH GUSTS TO 25 MPH. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 320 PM CDT SAT JUL 5 2014 FLOW ALOFT SHIFTS TO THE NORTHWEST MON/TUES WITH THE NEXT PRIMARY WAVE DROPPING ACROSS THE NORTHERN PLAINS MONDAY/MONDAY NIGHT. SEVERE WEATHER NOT EXPECTED...BUT SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE THROUGH THE DAY ON MONDAY WITH DRYING CONDITIONS FROM WEST TO EAST ON TUESDAY. FOR TUESDAY NIGHT THROUGH SATURDAY...SOME DISAGREEMENT IN HOW DEEP NEXT 500 MB TROUGH WILL BE OVER ONTARIO AND GREAT LAKES REGION. EITHER WAY FCST REGION WILL BE IN NORTHWEST FLOW ALOFT WITH EXITING SHORT WAVE TUESDAY NIGHT THEN GENERAL HIGH PRESSURE FOR WED-EARLY THU. NEXT SIGNIFICANT SHORT WAVE TO IMPACT US LATE THU-FRI. DIDNT STRAY FROM ALL BLEND TEMPS NOR POPS MUCH. OVERALL TEMP REGIME AFTER THIS WEEKEND FAVORS A RETURN TO JUST A FEW DEGREES BELOW AVERAGE FOR HIGH TEMPS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1145 PM CDT SAT JUL 5 2014 THUNDERSTORM CHANCES WILL BE THE MAIN CONCERN THROUGH THIS PERIOD...ESPECIALLY BEFORE SUNRISE. THERE SHOULD BE A BROKEN LINE OF STORMS THAT MOVE FROM WEST TO EAST THROUGH THE REGION. NOT SURE HOW WIDESPREAD THESE STORMS WILL BE...BUT DID TEMPO FOR THE MOST LIKELY PERIODS. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...TG SHORT TERM...ROGERS LONG TERM...ROGERS/RIDDLE AVIATION...TG
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1127 PM CDT SAT JUL 5 2014 .AVIATION... /06Z TAFS/ VFR expected for the next 24 hours with no significant aviation concerns. May see a few stratus near JCT around sunrise...but confidence too low to add MVFR ceiling. Will also see a few afternoon cumulus...but expecting a bit less than yesterday with drier air in place. Winds should increase out of the south at 10 to 15 kt by mid-morning. && .PREV DISCUSSION... /ISSUED 624 PM CDT Sat Jul 5 2014/ AVIATION... /00Z TAFS/ VFR expected for the next 24 hours. May see just a few stratus make it into the Northwest Hill Country and JCT area...but clouds should be brief. Left a scattered group of low clouds in for a few hours around sunrise. Otherwise...light southeast winds overnight will pick up to 10 to 15 kts tomorrow more out of the south. No significant aviation weather expected. PREV DISCUSSION... /ISSUED 347 PM CDT SAT JUL 5 2014/ SHORT TERM... (Tonight and Sunday) Cumulus development was more extensive over West Central Texas than yesterday. While the 17Z HRRR model reflectivity did indicated isolated shower and thunderstorm activity this afternoon, cumulus at 3 PM had limited vertical extent, and expect dry conditions this evening. Dry conditions continue Sunday as upper ridging holds over the region. Will maintain a persistence forecast, with lows in the lower 70s and highs in the mid 90s. LONG TERM... (Sunday night through next Saturday) Warm and dry conditions will continue across West Central Texas through next week. The center of the upper high will remain over the four corners region through midweek, then flatten and expand east across the Southern Plains through next Saturday. Models still show a weak TUTT moving into extreme south Texas and far northeastern Mexico by Wednesday. This feature will remain nearly stationary across this area through Thursday, then drift slowly west across Northern Mexico by early next weekend. About the only noticeable effect from the TUTT will be an increase in some diurnal cumulus by mid to late week. Temperatures through the extended period will remain at or slightly above seasonal normals for this time of year. && .PRELIMINARY POINT TEMPS/POPS... Abilene 72 94 71 96 72 / 5 5 5 5 5 San Angelo 72 95 69 96 72 / 5 5 5 5 5 Junction 69 94 70 95 70 / 5 5 5 5 5 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 08
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1044 AM CDT Sun Jul 6 2014 .UPDATE... Issued at 1043 AM CDT SUN JUL 6 2014 Appears HRRR had the best handle on the progress of the MCS remnants up to the present as stratiform showers and scattered convection have descended into southwest Missouri. Warming depicted by IR satellite though would suggest a general decrease in lift across the region associated with a dampening shortwave. Forecast update maintains southward moving precipitation through late morning...becoming more scattered in association with remnant MCV this afternoon. High temperatures have been reduced at least a category across all regions due to cloud cover though do anticipate some recovery in the west as sunshine resumes and south winds pick back up this afternoon. && .SHORT TERM...(Today and Monday) Issued at 310 AM CDT SUN JUL 6 2014 Thunderstorms have developed across north central Missouri to the southwest into southeastern Kansas early this morning. This activity has developed on the nose of a low level jet a ahead of a weak upper level disturbance that is tracking south through the region. This activity will continue to develop and track to the south this morning and will mainly affect locations along an northwest of an Anderson to Bolivar to Vichy Missouri line this morning. This activity will weaken and dissipate by the mid morning hours with the strongest activity generally occurring before sunrise this morning. A few strong storms will be possible early this morning with hail to the size of pennies the main risk mainly before 7 AM this morning then storms should generally weaken as the morning moves a long. A warmer and more humid air mass is spreading north into the region and highs will top out in the upper 80s to the lower 90s this afternoon with heat index values in the middle 90s to near the 100 degree mark. Isolated storms could develop mainly east of Highway 65 this afternoon, but some capping is not expected to completely erode and there will not be much in the way of forcing in place. Therefore, this activity will be very isolated, if it can develop at all, and most locations will remain dry. If storms are able to develop this afternoon, instability will increase in excess of 2000J/kg of ML Cape and this instability and theta-E differences greater than 25K would support a localized downburst wind risk with a few of the storms that can develop. Hot and humid conditions will occur again Monday as highs top out in the lower to middle 90s with heat index values in the upper 90s to around 100 degrees. An unstable air mass will once again be over the area, and with the heating of the day the cap should weaken enough for scattered storms to develop Monday afternoon. Theta-E differences greater than 25K combined with the unstably air mass will once again support a risk for localized damaging straight line winds with a few of the stronger storms Monday afternoon. .LONG TERM...(Monday Night through Saturday) Issued at 310 AM CDT SUN JUL 6 2014 An upper level trough will move out of the northern Plains on Monday night and southeast into the region on Tuesday along with a weak cold front. Storms are expected to develop along the front as it pushes south through the area. There will be a risk for strong to severe storms Tuesday afternoon given a moist and unstable air mass along with an increase in deep layer shear with the approach of the upper level trough. Hail to the size of quarters and winds in excess of 60 mph will be the main risks with this activity. Slightly cooler conditions will occur on Wednesday and Thursday behind the front with highs in the middle to upper 80s. An upper level ridge will begin to build towards the region by late in the week sending the front back to the north. A few storms may develop on Thursday and Friday as the front moves north. Warmer conditions are then expected this weekend as highs warm back into the 90s. && .AVIATION...(For the 12Z TAFS through 12Z Monday Morning) Issued at 647 AM CDT SUN JUL 6 2014 For the KSGF/KJLN/KBBG tafs: An area of scattered showers and thunderstorms will affect the KSGF and KJLN areas early, but in general expect vfr conditions for much of the taf period. The showers are expected to weaken over the next few hours. South winds will continue with sfc troughing remaining out of the Plains. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ UPDATE...Runnels SHORT TERM...Wise LONG TERM...Wise AVIATION...DSA
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
920 AM CDT Sun Jul 6 2014 .UPDATE... Issued at 919 AM CDT SUN JUL 6 2014 Updated POPs this morning to account for MCS descending southward into the western portion of the SGF CWA. HRRR is at odds with the new WRF as the HRRR maintains the MCS into the afternoon...while the 12z WRF follows the 06z WRF in diminishing the activity very rapidly this morning. Radar and IR trends do indicate a downward trend as the leading edge of the precipitation nears I-44...much in line with CIN gradient available from the SPC meso page. Typical MCS diurnal trends are supported by the strongly veered westerly low level jet though there is weak shortwave support. Updated POPs depict a diminishing trend though confidence is modest. && .SHORT TERM...(Today and Monday) Issued at 310 AM CDT SUN JUL 6 2014 Thunderstorms have developed across north central Missouri to the southwest into southeastern Kansas early this morning. This activity has developed on the nose of a low level jet a ahead of a weak upper level disturbance that is tracking south through the region. This activity will continue to develop and track to the south this morning and will mainly affect locations along an northwest of an Anderson to Bolivar to Vichy Missouri line this morning. This activity will weaken and dissipate by the mid morning hours with the strongest activity generally occurring before sunrise this morning. A few strong storms will be possible early this morning with hail to the size of pennies the main risk mainly before 7 AM this morning then storms should generally weaken as the morning moves a long. A warmer and more humid air mass is spreading north into the region and highs will top out in the upper 80s to the lower 90s this afternoon with heat index values in the middle 90s to near the 100 degree mark. Isolated storms could develop mainly east of Highway 65 this afternoon, but some capping is not expected to completely erode and there will not be much in the way of forcing in place. Therefore, this activity will be very isolated, if it can develop at all, and most locations will remain dry. If storms are able to develop this afternoon, instability will increase in excess of 2000J/kg of ML Cape and this instability and theta-E differences greater than 25K would support a localized downburst wind risk with a few of the storms that can develop. Hot and humid conditions will occur again Monday as highs top out in the lower to middle 90s with heat index values in the upper 90s to around 100 degrees. An unstable air mass will once again be over the area, and with the heating of the day the cap should weaken enough for scattered storms to develop Monday afternoon. Theta-E differences greater than 25K combined with the unstably air mass will once again support a risk for localized damaging straight line winds with a few of the stronger storms Monday afternoon. .LONG TERM...(Monday Night through Saturday) Issued at 310 AM CDT SUN JUL 6 2014 An upper level trough will move out of the northern Plains on Monday night and southeast into the region on Tuesday along with a weak cold front. Storms are expected to develop along the front as it pushes south through the area. There will be a risk for strong to severe storms Tuesday afternoon given a moist and unstable air mass along with an increase in deep layer shear with the approach of the upper level trough. Hail to the size of quarters and winds in excess of 60 mph will be the main risks with this activity. Slightly cooler conditions will occur on Wednesday and Thursday behind the front with highs in the middle to upper 80s. An upper level ridge will begin to build towards the region by late in the week sending the front back to the north. A few storms may develop on Thursday and Friday as the front moves north. Warmer conditions are then expected this weekend as highs warm back into the 90s. && .AVIATION...(For the 12Z TAFS through 12Z Monday Morning) Issued at 647 AM CDT SUN JUL 6 2014 For the KSGF/KJLN/KBBG tafs: An area of scattered showers and thunderstorms will affect the KSGF and KJLN areas early, but in general expect vfr conditions for much of the taf period. The showers are expected to weaken over the next few hours. South winds will continue with sfc troughing remaining out of the Plains. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ UPDATE...Runnels SHORT TERM...Wise LONG TERM...Wise AVIATION...DSA
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
734 AM CDT SUN JUL 6 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 311 AM CDT SUN JUL 6 2014 THERE ARE THREE PRIMARY FORECAST CHALLENGES CURRENTLY BEING CONSIDERED: -HEAT INDEX VALUES TODAY -CONVECTION CHANCES THIS AFTERNOON AND EVENING IN THE SOUTH -SEVERE AND HEAVY RAIN POTENTIAL FOR MONDAY AFTERNOON AND NIGHT AT 07Z...SURFACE COLD FRONT WAS ANALYZED FROM NORTH CENTRAL SOUTH DAKOTA INTO FAR NORTHWEST NEBRASKA AND HAD JUST MOVE THROUGH PINE RIDGE. FRONT SHOULD REACH SOUTHEAST NEBRASKA BY LATE AFTERNOON. AIRMASS OVER FORECAST AREA AHEAD OF THE FRONT WILL BE QUITE HUMID WITH DEWPOINTS IN THE LOW TO MID 70S...WITH ONLY SLIGHT COOLING BEHIND THE FRONT. ALOFT...WEAK RIDGING WAS NOTED UPSTREAM WITH MINOR HEIGHT RISES AT 500 MB ACROSS THE DAKOTAS INTO NEBRASKA...WITH FAIRLY WARM MID LEVEL TEMPERATURES. THEREIN LIES THE QUESTION OF THE PAST COUPLE OF DAYS...TRYING TO DETERMINE WHETHER THE FRONT WILL BE ABLE TO TRIGGER CONVECTION TODAY IN A WARM AIRMASS WITH A MODEST CAP AND A LACK OF DEEP VERTICAL MOTION FROM ANY DISTINCT LIFTING MECHANISM OTHER THAN THE FRONT. THE 00Z NAM AND THE 06Z RAP ARE IN GOOD AGREEMENT WITH DEVELOPING CONVECTION ALONG THE FRONT IN THE 22Z-23Z TIME FRAME...AND THE 00Z GFS DEVELOPS IT SLIGHTLY POST FRONTAL BETWEEN 00Z-06Z. NOT SURPRISINGLY...THE NAM AND RAP BOTH ERODE THE CAP FROM ABOUT LINCOLN SOUTH...AND INDICATE VERTICAL MOTION ON THE ORDER OF -4 MICROBARS/SEC THROUGH AROUND 600MB. GIVEN THESE POSSIBLE SCENARIOS...WILL GO WITH A SLIGHT CHANCE IN SOUTHEAST NEBRASKA/SOUTHWEST IOWA FROM 22Z-03Z. REGARDING THE HEAT AND HUMIDITY TODAY...THE COOLING BEHIND THE FRONT IS A CONCERN BUT NEARLY FULL SUN SHOULD KEEP TEMPERATURES FROM DROPPING MUCH. A DEGREE OR TWO DROP IN DEWPOINTS IS EXPECTED IN NORTHERN COUNTIES...BUT NOT IN SOUTHERN COUNTIES UNTIL WELL AFTER THE FRONT PASSES. GENERALLY HAVE NOT MADE CHANGES TO TEMPS TODAY...BUT DID RAISE DEWPOINTS A FEW DEGREES BASED ON READINGS SATURDAY. BOTTOM LINE IS HEAT INDEX VALUES OF 95-100 NORTH AND 100-105 SOUTH. LOOKS LIKE MOST SOUTHERN COUNTIES WILL REMAIN JUST SHY OF HEAT ADVISORY CRITERIA. MODELS IN REASONABLY GOOD AGREEMENT WITH WET PATTERN FOR MONDAY AFTERNOON INTO MONDAY NIGHT. CURRENT FORECAST HAS THIS PERIOD HANDLED WELL. ONLY CHANGES WILL BE TO INCREASE POPS FOR NORTHWEST AREAS MONDAY AFTERNOON...AND ALSO MENTION HEAVY RAIN MONDAY NIGHT ESPECIALLY SOUTH OF I-80 WHERE RECENT RAINS HAVE CAUSED FLOODING IN SOUTHWEST IOWA. HEAVY RAIN OVER THE SOUTHERN COUNTIES LOOKS POSSIBLE GIVEN THE STRONG FRONTAL CONVERGENCE IN THE LOW LEVELS FOR 9-12 HOURS... JET DIVERGENCE AND SHEARED VORTICITY IN NORTHWEST FLOW CAUSING A PROLONGED PERIOD OF LIFT...AND ABUNDANT MOISTURE/INSTABILITY. NAM AND GFS SHOW QUITE STRONG THETA-E ADVECTION FROM 850-700. THIS IS A CONCERN GIVEN THE CURRENT FLOODING IN THE NISHNABOTNA RIVER BASIN IN SOUTHWEST IOWA. WPC DAY 2 EXCESSIVE RAIN GRAPHIC SUPPORTS THIS AS WELL. INGREDIENTS FOR SEVERE CONVECTION MONDAY AFTERNOON AND EVENING APPEAR TO BE LINING UP...PER SPC DAY 2 DISCUSSION. INSTABILITY AND DEEP LAYER SHEAR PARAMETERS MORE THAN SUPPORT A SEVERE WEATHER OUTBREAK WITH UNSEASONABLY FAST UPPER FLOW. BOWING SEGMENTS ALONG THE FRONTAL BOUNDARY IN SOUTHEAST NEBRASKA/SOUTHWEST IOWA SEEM LIKELY. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 311 AM CDT SUN JUL 6 2014 BY LATE TUESDAY THE PRIMARY SYNOPTIC FRONT SHOULD MOVE WELL SOUTH OF THE AREA WITH SURFACE HIGH PRESSURE MOVING INTO THE FORECAST AREA. DRY CONDITIONS ARE EXPECTED TUESDAY NIGHT INTO WEDNESDAY. BY THURSDAY...RETURN FLOW BRINGS MOISTURE BACK INTO THE REGION AND THE UPPER PATTERN MAINTAINS A SOMEWHAT UNSETTLED NORTHWEST FLOW REGIME WITH SOME POTENTIAL FOR MCS ACTIVITY...BUT CONFIDENCE IS LOW THURSDAY INTO SATURDAY. TEMPERATURES SHOULD BE CLOSE TO NORMAL OR A FEW DEGREES BELOW NORMAL. && .AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 734 AM CDT SUN JUL 6 2014 DENSE FOG/LOW CIGS HAVE SET IN AT KOFK...RECENT OBSERVATIONS INDICATE THIS CONDITION WILL SLOWLY IMPROVE TO VFR IN THE NEXT THREE HOURS. LIGHT FOG HAS BEEN REPORTED AT THE OTHER SITES AND BY 15Z ALL THREE SITES SHOULD BE INTO VFR. A SCATTERED TO BROKEN MID DECK WILL PUSH THROUGH THE AREA THIS AFTERNOON...BUT DO NOT ANTICIPATE ANYTHING OTHER THAN VFR. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...NIETFELD LONG TERM...NIETFELD AVIATION...PEARSON
AREA FORECAST DISCUSSION
NWS TULSA OK
1037 AM CDT SUN JUL 6 2014 .DISCUSSION... LATEST RUNS OF THE HRRR SUGGEST AT LEAST SOME CHANCE OF SHOWERS AND ISOLATED STORMS WILL LINGER INTO THE AFTERNOON OVER NORTHWEST AR IN ASSOCIATION WITH A DISTURBANCE...POSSIBLY EVEN AN MCV...TRACKING SOUTHEAST ACROSS MO ATTM. THE FORECAST HAS BEEN ADJUSTED AND WILL CONTINUE TO MONITOR THE TRENDS. LACY && .PREV DISCUSSION... /ISSUED 837 AM CDT SUN JUL 6 2014/ DISCUSSION... A LOOSELY ORGANIZED MCS IS TRACKING ACROSS SOUTHWEST MO AND FAR NORTHEAST OK ATTM...IN ASSOCIATION WITH A WAVE (CONVECTIVELY ENHANCED MOST LIKELY) WRAPPING AROUND THE MID LVL RIDGE CENTERED OVER THE CENTRAL ROCKIES. THE SOUTHWEST FLANK IS WEAKENING AS IT TRACKS SOUTHEAST...WITH THE NORTHEAST FLANK REMAINS MORE INTENSE. HAVE THEREFORE INCREASED POPS OVER IN NORTHWEST AR WHERE THE STRONGER ACTIVITY IS HEADED. WILL INCREASE POPS MORE IF NEEDED. LACY PREV DISCUSSION... /ISSUED 631 AM CDT SUN JUL 6 2014/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE ACROSS PARTS OF NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS THIS MORNING. BVO LOOKS TO HAVE THE GREATEST CHANCE OF SEEING PRECIP AND WILL CARRY -RA/VCTS...WHILE KEEPING THE REST OF THE TAF SITES DRY DUE TO LIMITED COVERAGE. OTHERWISE...SCATTERED TO BROKEN MID/HIGH CLOUD DECKS AND BREEZY SOUTHERLY WINDS WILL BE COMMON ACROSS THE REGION TODAY. SOUTHERLY WINDS DECREASE TONIGHT WITH SCATTERED HIGH CLOUDS PERSISTING. VFR CONDITIONS SHOULD CONTINUE THROUGH THE PERIOD. PREV DISCUSSION... /ISSUED 406 AM CDT SUN JUL 6 2014/ DISCUSSION... A FEW SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE ACROSS NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS THIS MORNING AS THE TAIL END OF A SHORTWAVE BRUSHES ACROSS THIS AREA. OTHERWISE THE HEAT WILL BE BUILDING TODAY AND MONDAY AS AN UPPER RIDGE BUILDS OVER THE AREA. SOME MODELS BRING TRIPLE DIGIT HEAT INTO THE WESTERN PART OF THE FORECAST AREA ESPECIALLY MONDAY BUT WILL NOT GO QUITE THAT HOT. A WEAK COLD FRONT WILL MOVE SOUTH INTO THE AREA TUESDAY AFTERNOON AND PROVIDE A FOCUS FOR SCATTERED SHOWERS AND THUNDERSTORMS. THE FRONT WILL STALL WEDNESDAY AND THEN LIFT BACK NORTH AS A WARM FRONT THURSDAY WHICH WILL CONTINUE THE CHANCES FOR SHOWERS AND THUNDERSTORMS. THE UPPER RIDGE BUILDS BACK OVER THE AREA BY NEXT WEEKEND AND BEYOND BRINGING TEMPERATURES AS HOT OR HOTTER THAN WHAT WE WILL SEE THE NEXT COUPLE DAYS. STAYED CLOSE TO GUIDANCE TEMPERATURES THE NEXT COUPLE DAYS. && .PRELIMINARY POINT TEMPS/POPS... TUL 95 75 97 77 / 20 10 0 10 FSM 93 73 96 74 / 10 0 10 10 MLC 93 74 94 75 / 0 0 0 0 BVO 94 72 97 74 / 20 10 0 10 FYV 88 69 91 70 / 30 0 10 10 BYV 88 69 92 71 / 30 10 10 10 MKO 93 72 95 74 / 20 0 0 0 MIO 90 72 95 74 / 20 10 10 10 F10 93 73 95 74 / 20 0 0 0 HHW 92 72 93 73 / 0 0 10 0 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...30
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
919 AM CDT SUN JUL 6 2014 .UPDATE... SEE DISCUSSION FOR MORNING UPDATE. && .DISCUSSION... NOT MUCH CHANGE IN PATTERN FROM YESTERDAY. SCATTERED SHOWERS AND THUNDERSTORMS HAVE FORMED OVER THE WATERS THIS MORNING AND HAVE STARTED TO MOVE INLAND. GFS AND NAM FORECAST SOUNDINGS SHOWING PWATS AROUND 1.7" THIS AFTERNOON WITH K INDICES IN THE LOWER TO MID 30S. EXPECTING COVERAGE TO INCREASE OVER INLAND AREAS THIS AFTERNOON THANKS TO DAY TIME HEATING. HIGH RES HRRR AND TEXAS TECH WRF AGAIN SHOWING GREATEST CHANCES TOWARDS THE SOUTHWEST. GRANTED THEY HAVE NOT INITIALIZED GREAT. COVERAGE MIGHT AGAIN BE MORE THAN 40 PERCENT IN SOME AREAS BUT GIVEN MESOSCALE NATURE OF STORMS HARD TO PIN POINT EXACT LOCATION. CURRENT FORECAST HAS TAKEN THE ABOVE INTO ACCOUNT. NO UPDATE REQUIRED AT THIS TIME. 23 && .PREV DISCUSSION... /ISSUED 355 AM CDT SUN JUL 6 2014/ DISCUSSION... CURRENT FCST LOOKS GOOD AND MADE VERY FEW CHANGES TO IT. EXPECT GENERAL PATTERN OF ISO/SCT PRECIP TO DEVELOP OFFSHORE LATE NIGHT & EARLY MORNING THEN TRANSITION INLAND DURING THE DAY COMPLIMENTS OF DAYTIME HEATING AND THE SEABREEZE. OVERALL COVERAGE DEPENDS ON SLIGHT VARIATIONS OF MOISTURE AVAILABILITY & LOCATION EACH DAY. SFC HIGH PRES SHOULD REMAIN CENTERED OFF TO THE EAST ALLOWING WEAK ONSHORE FLOW TO PERSIST. FURTHER ALOFT...LOOKS LIKE WE`LL REMAIN IN A SLIGHT WEAKNESS BETWEEN RIDGES. SOME OF THE MEDIUM RANGE SOLNS DO SUGGEST UPPER RIDGE BUILDING FURTHER OVERHEAD TOWARD NEXT WEEKEND WHICH WOULD BRING RAIN CHANCES DOWN AND TEMPS UP. JUST SOMETHING TO KEEP AN EYE ON - BUT PERSISTENCE FCST WILL DO FOR NOW. 47 MARINE... AS HIGH PRESSURE EDGES OFF TO THE EAST THE ONSHORE FLOW SHOULD BE IN- CREASING SLIGHTLY THE NEXT DAY OR SO. THESE LIGHT/MODERATE WINDS ARE FCST TO PERSIST FOR MUCH OF THE WEEK AS THE WX PATTERN REMAINS GENER- ALLY QUIET. NO ADVISORIES/CAUTION FLAGS ARE ANTICIPATED EXPECTED THE NEXT SEVERAL DAYS. 41 AVIATION... CALM WINDS/WET GROUNDS HELPING TO PRODUCE SOME PATCHY/SHALLOW GROUND FOG THIS MORNING. NOT EXPECTING ANY SIGNIFICANT VIS/CIG RESTRICTIONS THROUGH MID MORNING AS ALL OF THIS SHOULD MIX OUT BY THEN. OTHERWISE SHORT TERM GUIDANCE INDICATING THAT THE BEST CHCS FOR PCPN WILL BE A BIT FURTHER W/SW THIS AFTN BUT ISO ACTIVITY ALONG/NEAR THE SEABREEZE CANNOT BE TOTALLY RULED OUT (GIVEN THE TRENDS THESE LAST FEW DAYS). AS SUCH MAY ADD VCSH FOR SOME OF THE CENTRALLY LOCATED TAFS (SGR/HOU AND LBX) FOR THIS AFTN. 41 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 93 73 93 74 93 / 20 20 30 10 20 HOUSTON (IAH) 92 74 92 75 92 / 30 20 30 10 30 GALVESTON (GLS) 89 79 89 80 90 / 30 20 20 20 20 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...23
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1033 AM CDT SUN JUL 6 2014 .UPDATE...CONSIDERABLE DEBRIS CLOUDINESS UPSTREAM ALONG WITH LOW LEVEL STRATUS FIELD WHICH HAS LEAD TO THE SHAKING OF CONFIDENCE FOR HOW STORMS WILL EVOLVE LATER. THE PLAN IS IT IS TILL EARLY AND THIS TIME OF YEAR THIS LOWER STRATUS SHOULD BURN OFF BURN OFF TO ALLOW FOR THE BUILDUP OF CAPE. MORE SUN ACRS SE WI BUT INITIATION POINT IS EXPECTED FURTHER WEST IN WC WI WHERE THE CLOUD COVER IS. CONCERN ATTM IS THAT WE ARE NOT SEEING ANY DECREASE IN CLOUD COVER EVOLVE. MID LEVEL JET STREAK STILL EXPECTED TO ENCROACH ON THE AREA THIS AFTERNOON WITH TIGHTENING 500 MILLIBAR HEIGHT GRADIENT. WITHIN THIS IS A WEAK SHORTWAVE THAT WILL AID IN VERTICAL MOTION. UPPER JET FURTHER NORTH HOWEVER SOME DIFFLUENCE NOTED ACRS CNTRL/SRN WI MODEL PROGGD DIVERGENCE IN RESPONSE TO THIS. SPC SUGGESTS THIS CLOUDINESS MAY RESULT IN CONVECTION BEING TIED TO THE FRONTAL ZONE BUT MODULATED BY HOW QUICK THESE CLOUDS AHEAD OF IT CAN THIN. 00Z NMM/ARW ARE STILL RATHER ROBUST BUT DO NOT BELIEVE THESE MODELS FROM LAST NIGHT HAVE A HANDLE ON THESE LOW CLOUDS. MEANWHILE THE 13Z HRRR SHOWING SOME STRONGER STORMS BUT NOT NEARLY AS WHAT THE OTHER 00Z MODELS WERE SHOWING. 12Z NAM SHOWS QPF BULLSEYE ACRS ERN CWA BETWEEN 18-00Z...SO FRONT COULD END UP INITIATING CONVECTION INTO A MORE UNSTABLE AIRMASS ACROSS OUR CWA WHERE SOME SUN IS HEATING THINGS UP. SO LOTS OF UNCERTAINTY AT THE MOMENT WITH THE THERMODYNAMICS BEING THE MAIN QUESTION MARK. DYNAMICALLY/FORCING WISE...ALL SYSTEMS ARE STILL GO. PC && .AVIATION/18Z TAFS/...PLENTY OF STRATUS ACRS NW 1/2 OF THE CWA THOUGH EXPECTING SOME BURNOFF AS THE HEATING OF THE DAY INCREASES. MAIN CHALLENGE CENTERS ON CONVECTIVE DEVELOPMENT WITH ALL OF THE UPSTREAM CLOUDINESS HINDERING THE CAPE BUILDUP ATTM. HOWEVER STILL EXPECT SOME THINNING AND SUBSEQUENT DESTABILIZATION TO MAINTAIN A THREAT OF SOME STRONGER OR SEVERE STORMS LATER THIS AFTERNOON INTO THE EVENING HOURS AS MID LEVEL STREAK/SHORTWAVE AND SURFACE COLD FRONT APPROACH THE AREA. BUT THERE IS UNCERTAINTY ATTM. ANY STORMS EXPECTED TO BE SOUTHEAST OF THE AREA BY 6Z WITH WEAK RIDGING TAKING HOLD FOR MUCH OF MONDAY. PC && .PREV DISCUSSION... /ISSUED 348 AM CDT SUN JUL 6 2014/ TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM. AREA OF LOW STRATUS CLOUDS OVER MOST OF THE AREA SHOULD LINGER INTO THE MORNING HOURS...BEFORE DAYTIME HEATING MIXES THIS LAYER OUT. SYNOPTIC AND MESOSCALE MODELS SHOWING COLD FRONT MOVING EASTWARD ACROSS THE AREA LATER THIS AFTERNOON THROUGH THE LATE EVENING HOURS. A 500 MB VORTICITY MAXIMUM ACCOMPANIES THE FRONT. THE FRONT MOVES INTO THE FAR WESTERN COUNTIES DURING PEAK HEATING. WARM AND HUMID CONDITIONS ARE EXPECTED...WITH MID 80S F FOR HIGHS...AND DEW POINTS AROUND 70 F. MEAN LAYER CAPES OF 2000 TO 2500 J/KG ARE EXPECTED. 0 TO 6 KM SHEAR VALUES OF 20 TO 30 KNOTS ARE EXPECTED AS WELL...WITH PRECIPITABLE WATER VALUES OF AROUND 1.75 INCHES...2 STANDARD DEVIATIONS ABOVE NORMAL. AREA FORECAST SOUNDINGS DO SHOW A CAP TO BE OVERCOME...WHICH SHOULD OCCUR BETWEEN 21Z SUNDAY AND 00Z MONDAY. CONVECTION IS LIKELY TO OCCUR FROM WEST TO EAST WITH THE FRONT...BEGINNING AS DISCRETE CELLS BEFORE BECOMING MORE LINEAR IN NATURE. SPC HAS AREA IN SLIGHT RISK FOR SEVERE STORMS IN DAY 1 OUTLOOK LATER THIS AFTERNOON AND THIS EVENING. LARGE HAIL AND DAMAGING WINDS ARE CERTAINLY POSSIBLE. 0 TO 1 KM SHEAR VALUES OF 10 TO 20 KNOTS DOES SUPPORT AN ISOLATED TORNADO RISK AS WELL...WITH LOW LCLS EXPECTED. CONVECTION SHOULD DIMINISH BY 06Z MONDAY...ONCE UPWARD VERTICAL MOTION SHIFTS TO THE EAST. TEMPERATURES SHOULD ONLY FALL INTO THE UPPER 60S TO AROUND 70 FOR LOWS TONIGHT. MONDAY...FORECAST CONFIDENCE...MEDIUM ANOTHER ROUND OF STORMS EXPECTED MONDAY EVENING INTO THE NIGHT AS A SHORTWAVE PUSHES THROUGH. INCREASED POPS GIVEN DECENT WARM ADVECTION IN THE LOW AND MID LEVELS...ALONG WITH SOME UPPER LEVEL DIVERGENCE. LOOKS LIKE A BIT LESS OF A SEVERE CHANCE THAN TODAY DUE THE LATER TIMING AND LESS INSTABILITY...THOUGH 0-6 KM BULK SHEAR OF 40-50 KNOTS WILL PROBABLY KEEP THINGS INTERESTING. SPC DOES HAVE THE DAY 2 SLIGHT RISK INTO THE FAR WEST FORECAST AREA. TEMPS MONDAY ARE EXPECTED TO BE ON THE WARM SIDE AGAIN...WITH 925 MB TEMPS GENERALLY IN THE 22-24C RANGE. SHOULD SEE A GOOD AMOUNT OF SUN...SO WENT MID 80S MOST PLACES. TUESDAY AND WEDNESDAY...FORECAST CONFIDENCE...MEDIUM A COUPLE OF WEAK WAVES MAY BRING A FEW SHOWERS AND STORMS TUESDAY AND WEDNESDAY. THERE WILL BE MUCH LESS MOISTURE TO WORK WITH...AS PRECIPITABLE WATER VALUES WILL BE AROUND AN INCH TUE...AND EVEN LESS THAN THAT WED. FORCING IS ON THE WEAK SIDE TOO...SO KEPT POPS ON THE LOW END. THURSDAY THROUGH SATURDAY...FORECAST CONFIDENCE...MEDIUM INCREASING WARM ADVECTION FROM THE SOUTHWEST MAY KICK OF A FEW SHOWERS/STORMS LATER FRIDAY...BUT OTHERWISE IT LOOKS LIKE A DRY END TO THE WORK WEEK. SHOWER/STORM CHANCES ARE THEN EXPECTED TO INCREASE FRIDAY NIGHT INTO SATURDAY AS A SHORTWAVE MOVES THROUGH. SHOULD SEE HIGH TEMPS WITHIN A COUPLE DEGREES OF NORMAL THU-SAT. AVIATION/12Z TAFS/... MVFR CEILINGS WITH LOW STRATUS CLOUDS SHOULD LINGER INTO THE MORNING HOURS ACROSS MADISON...WITH THE EASTERN SITES IN AND OUT OF IT. THESE CLOUDS SHOULD DISSIPATE BY AROUND 18Z SUNDAY. SOUTH SOUTHWEST WINDS SHOULD BECOME GUSTY AT TIMES BY THE AFTERNOON...GUSTING TO AROUND 22 KNOTS BY LATER IN THE AFTERNOON. DIURNAL CUMULUS SHOULD DEVELOP AS WELL. COLD FRONT WITH THUNDERSTORMS SHOULD AFFECT MADISON BETWEEN 22Z SUNDAY AND 02Z MONDAY...AND THE EASTERN SITES BETWEEN 00Z AND 04Z SUNDAY. STRONG GUSTY WINDS AND LARGE HAIL ARE POSSIBLE WITH ANY SEVERE STORMS...ALONG WITH VISIBILITIES DOWN TO ALTERNATE MINIMUMS. WINDS WEAKEN AND SHIFT TO THE WEST AFTER 06Z MONDAY...WITH CLOUDS GRADUALLY THINNING OUT FROM WEST TO EAST. MARINE... SMALL CRAFT ADVISORY CONTINUES FROM 18Z SUNDAY TO 03Z MONDAY ACROSS THE NEARSHORE WATERS. FREQUENT SOUTH SOUTHWEST WIND GUSTS TO 22 TO 25 KNOTS SHOULD OCCUR DURING THIS TIME...WITH GOOD MIXING OF THE LOW LEVEL WINDS. WAVES SHOULD BUILD TO 3 TO 4 FEET NEAR SHEBOYGAN...WITH 2 TO 4 FOOT WAVES TO THE SOUTH. WINDS AND WAVES WILL SUBSIDE TONIGHT AFTER COLD FRONT MOVES INTO THE AREA. BEACHES... A MODERATE SWIM RISK IS EXPECTED FOR SHEBOYGAN AND OZAUKEE COUNTY BEACHES ALONG LAKE MICHIGAN LATER THIS MORNING INTO EARLY THIS EVENING. THE WINDS WILL BE SOUTH TO SOUTH SOUTHWEST AND GUSTY...GENERATING WAVES OF UP TO 3 TO 4 FEET. THIS WILL POSE SOME RISK TO SWIMMERS IN THESE AREAS. WILL NOT ISSUE A BEACH HAZARDS STATEMENT AT THIS TIME. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 10 PM CDT THIS EVENING FOR LMZ643>646. && $$ TODAY/TONIGHT AND AVIATION/MARINE...WOOD MONDAY THROUGH SATURDAY...DDV
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
245 PM CDT SUN JUL 6 2014 .SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT SFC HIGH PRES WAS SITUATED TO THE E OF AR THIS AFTN...ALLOWING SLY WINDS TO RETURN TO THE REGION. LOW LVL MOISTURE HAS RETURNED IN EARNEST OVR THE LAST 24 HOURS AS NOTED WITH LATEST DEWPOINT READINGS IN THE MID 60S TO LOWER 70S ACRS THE FA. CONVECTIVE COMPLEX THAT WAS NOTED ACRS SWRN MO EARLIER IN THE DAY HAS CONTD TO WEAKEN. THE RESULTING MCV IS EXPECTED TO DRIFT SLOLY TO THE SE INTO THE EVENING. THE HRRR CONTS TO HAVE A GOOD HANDLE ON THIS FEATURE AND DOES INDC SOME ADDITIONAL CONVECTION FORMING ACRS PARTS OF NRN AR THRU THE LATE AFTN. WL CONT TO MONITOR RADAR TRENDS AND DECIDE BEFORE ISSUANCE TIME WHETHER TO INCLUDE SOME POPS THIS EVENING IN THE N. THE WX PATTERN WL BCM MORE UNSETTLED HEADING INTO THE MIDDLE OF THE NEW WORK WEEK. HIGH PRES ALOFT WL SHIFT FURTHER WWD AND SET UP OVR THE WRN PART OF THE NATION. THE RESULTING NWLY FLOW ALOFT WL BRING A FNTL BNDRY SWD INTO AR STARTING LATE TUE/TUE NGT...WITH THE BNDRY TO MEANDER OVR THE FA THRU THE REST OF THE SHORT TERM. AS A RESULT...CONVECTIVE CHCS WL BE ON THE UPSWING FM N TO S...ESP LATE TUE THRU WED. WHILE WIDESPREAD SVR WX IS NOT ANTICIPATED...A FEW STRONG/SVR STORMS WL BE POSSIBLE TUE NGT AND WED. SHLD THE BNDRY HOLD UP LONGER OVR A GIVEN AREA...LOCALLY HEAVY RAINFALL WL BE A CONCERN. DID NOT STRAY TOO FAR FM MOS TEMPS THRU THE PD. && .LONG TERM...THURSDAY THROUGH SUNDAY A STALLED FRONTAL BOUNDARY WILL BE PRESENT ACROSS ARKANSAS AS THE PERIOD BEGINS ON THURSDAY. BROAD-BRUSHED CHANCE POPS ARE IN THE FORECAST TO ACCOUNT FOR EXPECTED SCATTERED SHOWERS AND THUNDERSTORMS ON THURSDAY...POSSIBLY LINGERING INTO FRIDAY IN THE EAST. UPPER LEVEL HIGH PRESSURE WILL BEGIN STRENGTHENING TO THE WEST OF ARKANSAS ON FRIDAY...PUSHING THE REMNANT BOUNDARY OFF TO THE NORTHEAST AND LIKELY BRINGING RAIN CHANCES TO AN END FOR THE FORECAST AREA HEADING INTO NEXT WEEKEND. TEMPERATURES WILL BE AROUND OR POSSIBLY SLIGHTLY BELOW NORMAL ON THURSDAY DUE TO CLOUDS AND RAINFALL. HOWEVER...WITH A NOTABLE STRENGTHENING OF THE UPPER RIDGE AND SOUTHWEST WINDS IN PLACE IN THE LOWEST SEVERAL THOUSAND FEET OF THE ATMOSPHERE...A WARMING TREND WILL BEGIN THAT WILL CARRY THROUGH NEXT WEEKEND. SOME MODEL GUIDANCE IS EVEN HINTING AT THE POSSIBILITY OF TRIPLE DIGIT HIGHS NEXT SATURDAY AND SUNDAY. HOWEVER...WILL JUST ADVERTISE WIDESPREAD MID 90S FOR THE TIME BEING. RECENT RAINS AS WELL AS THOSE EXPECTED THIS WEEK SHOULD LIMIT THE POTENTIAL TO GET TO 100 DEGREES...MUCH LESS BEYOND. NEVERTHELESS...IT DOES SEEM LIKE NEXT WEEKEND MAY FEATURE OPPRESSIVE HEAT. TO END ON A POSITIVE NOTE THOUGH...LOOKING JUST BEYOND THE 7 DAY FORECAST THERE ARE INDICATIONS THAT ANY OPPRESSIVE HEAT MAY BE SHORT LIVED AND A RETURN TO NORMAL OR POSSIBLY BELOW NORMAL TEMPERATURES COULD OCCUR. TIME WILL TELL. && .LZK WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...44 / LONG TERM...64
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
107 PM PDT SUN JUL 6 2014 .SYNOPSIS... HIGH PRESSURE ANCHORED OVER THE FOUR CORNERS REGION WILL KEEP ABOVE NORMAL TEMPERATURES ACROSS THE CENTRAL CALIFORNIA INTERIOR THROUGH MUCH OF NEXT WEEK. SHOWERS AND THUNDERSTORMS WILL FORM OVER THE SIERRA NEVADA AS TROPICAL MOISTURE FLOWS OVER THE AREA. && .DISCUSSION...UPPER LEVEL HIGH PRESSURE OVER THE FOUR CORNERS REGION CONTINUES TO BRING ABUNDANT MONSOONAL MOISTURE INTO AZ AND NV...AND EVEN INTO SOUTHERN AND CENTRAL CA. THUNDERSTORMS HAVE FORMED OVER THE SIERRA CREST IN TULARE COUNTY...BUT HAVE BEEN VERY ISOLATED IN NATURE. THE SHORT TERM MODELS INCLUDING THE HRRR AND THE NAM INDICATE THAT THESE STORMS WILL CONTINUE INTO THE EARLY EVENING HOURS AND PEAK AROUND THE 22Z...THE WARMEST PART OF THE DAY. INSTABILITY IS MARGINAL AT BEST...SO THUNDERSTORM ACTIVITY WILL LIKELY REMAIN ISOLATED...AND MAY NOT EVEN IMPACT THE KERN COUNTY MOUNTAINS AND DESERT AS CURRENTLY FORECAST. FORECASTER CONFIDENCE IS MEDIUM TO LOW WITH TIMING AND LOCATION OF THUNDERSTORMS. OTHERWISE...THE VALLEY IS ON ITS WAY TO ANOTHER TRIPLE DIGIT DAY...WITH MOST LOCATIONS IN THE MID TO UPPER 90S. TEMPERATURES WILL WARM INTO THE 100 TO 105 DEGREE MARK FOR MANY VALLEY LOCATIONS...NEARLY IDENTICAL TO THOSE OBSERVED YESTERDAY AND BETWEEN 5 AND 10 DEGREES ABOVE NORMAL FOR THE BEGINNING OF JULY. LITTLE CHANGE IN THE OVERALL SYNOPTIC PATTERN WITH THE FOUR CORNERS UPPER HIGH REMAINING FIRMLY IN PLACE INTO AT LEAST THURSDAY. THIS WILL BRING THE SLIGHT CHANCE OF THUNDERSTORMS TO THE SIERRA CREST EACH AFTERNOON/EVENING AND TRIPLE DIGIT TEMPERATURES TO THE VALLEY AND DESERT LOCATIONS. THE UPPER RIDGE SHIFTS SLOWLY EAST THURSDAY INTO FRIDAY...SHIFTING THE THUNDERSTORM MOISTURE SOURCE TO THE EAST AS WELL. ALTHOUGH WE DO HAVE A SLIGHT CHANCE FOR THUNDERSTORMS OVER THE CREST ON FRIDAY...CONFIDENCE IS LOW. ANOTHER RESULT OF THE UPPER HIGH SHIFTING EAST WILL BE A VERY SUBTLE COOLING TREND THROUGH THE AREA. ON FRIDAY...TEMPERATURES WILL STRUGGLE TO REACH THE 100 DEGREE MARK...BUT WILL LIKELY WARM INTO THE UPPER 90S. REGARDLESS...IT WILL HARDLY BE NOTICEABLE...AND STILL SLIGHTLY ABOVE NORMAL FOR THE MIDDLE OF JULY. && .AVIATION... SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED OVER THE KERN COUNTY DESERTS...TEHACHAPI MOUNTAINS AND THE HIGH COUNTRY OF THE SOUTHERN SIERRA NEVADA THRU 06Z MON AND OVER THE HIGH COUNTRY OF THE SOUTHERN SIERRA NEVADA AFTER 20Z MON. LOCAL IFR CONDITIONS WILL BE POSSIBLE NEAR ANY THUNDERSTORMS THAT DEVELOP. OTHERWISE VFR CONDITIONS WILL PREVAIL OVER THE REGION DURING THE NEXT 24 HOURS. && .AIR QUALITY ISSUES... NONE. && .CERTAINTY... THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS MEDIUM. THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM. CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL INFORMATION AND/OR TO PROVIDE FEEDBACK. && .CLIMATE... RECORDS SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR KFAT 07-06 111:2007 83:1903 78:2007 50:1955 KFAT 07-07 111:1905 84:1891 76:1936 53:1903 KFAT 07-08 115:1905 84:1983 81:1896 51:1891 KBFL 07-06 116:1913 85:1955 81:2011 52:1915 KBFL 07-07 114:1905 85:1983 81:1968 46:1903 KBFL 07-08 114:1905 85:1983 79:1907 50:1899 && .HNX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ PUBLIC...RILEY AVN/FW...DS SYNOPSIS...BSO WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS DES MOINES IA
554 PM CDT SUN JUL 6 2014 .SHORT TERM /TONIGHT/... ISSUED AT 319 PM CDT SUN JUL 6 2014 CLOUDS TODAY CONTINUE TO COMPLICATE THIS EVENINGS CONVECTION CHANCES. LOW LEVEL STRATUS WHICH FORMED IN THE SOUTHERLY MOISTURE FEED ACROSS THE AREA HAVE KEPT TEMPERATURES ABOUT 5 TO 7 DEGREES COOLER THAN FORECAST. ALOFT WE ARE ALSO DEALING WITH A SUFFICIENT MID LEVEL CAP AT H700 WITH TEMPS FROM 10 TO 12C IN THE WARM SECTOR THAT HAS TENDED TO KEEP CONVECTION EAST OF THE AREA. COMBINED WITH RELATIVELY WEAK CONVERGENCE ALONG THE APPROACHING COOL FRONT... AFTERNOON CONVECTION HAS BEEN SLOW TO TAKE OFF ALONG THE BOUNDARY IN MN/WESTERN WI. BUFR SOUNDINGS SHOW THAT CAP SHOULD REMAIN IN PLACE ALONG AND WEST OF I35 THIS EVENING...WHILE ERODING EAST OF THAT LINE WITH THE HELP OF THE DEVELOPING CONVECTION WHICH SHOULD BUILD BACK WEST SOUTHWEST WITH TIME THROUGH 06Z. GENERALLY SCATTERED CONVECTION IS EXPECTED ACROSS THE AREA SINCE THE CAP ALOFT WILL BE STRONGER AS THE STORMS MOVE BACK WEST INTO IOWA. NEARLY ALL THE MODELS INCLUDING THE HRRR FAVOR THIS SCENARIO. SO...HAVE TRIMMED POP/THUNDERSTORM CHANCES FROM I35 WEST WITH THE EXCEPTION OF AREAS ALONG THE IA/MO BORDER WHERE LATE MID EVENING SOME RESIDUAL CONVECTION MAY LINGER ALONG THE BOUNDARY. AIRMASS OVER EASTERN AND NORTHERN IA STILL RATHER UNSTABLE AND ANY STORMS THAT BUILD BACK TO THE WEST WILL STILL HAVE A CHANCE TO PRODUCE SVR WIND GUSTS AND LARGE HAIL. .LONG TERM /MONDAY THROUGH SUNDAY/... ISSUED AT 319 PM CDT SUN JUL 6 2014 INITIALLY CONDITIONS ARE EXPECTED TO BE QUIET MONDAY MORNING WITH SURFACE BOUNDARY STALLED IN MO/KS. SHORTWAVE WILL BE RAPIDLY ADVANCING SOUTHEAST THROUGH THE NORTHERN PLAINS. MODELS ALL INDICATE SURFACE MOISTURE RETURNING WITH DEWPOINTS INTO THE U60S/L70S BY AFTERNOON. HOWEVER...BEST LOW LEVEL CONVERGENCE APPEARS TO REMAIN JUST SOUTH OF IOWA AND THIS WILL LIKELY BE THE FOCUS OF THE MOST INTENSE CONVECTION BY LATE AFTERNOON INTO MONDAY NIGHT. THIS CONVECTION WILL LIKELY IMPACT SOUTHWEST THIRD OR SO OF THE STATE WITH THE POTENTIAL FOR SEVERE WINDS AND LARGE HAIL. HEAVY RAINS WILL ALSO BE POSSIBLE ALTHOUGH THE FOCUS AGAIN MAY BE JUST SOUTH AND WEST OF THE STATE WHERE BEST LOW LEVEL CONVERGENCE IS EXPECTED TO OCCUR. OTHERWISE...STRONG MID LEVEL FORCING WILL PRODUCE CONVECTION FARTHER NORTHEAST THROUGH MUCH OF THE REMAINDER OF CENTRAL IOWA LATE MONDAY AFTERNOON/EVENING BUT WITH LESS COVERAGE. DRIER AIR WILL FITLER INTO THE STATE IN THE WAKE OF THE SYSTEM ON TUESDAY WITH RELATIVELY QUIET WEATHER INTO THE MIDDLE OF THE WEEK WITH TEMPERATURES AT OR BELOW SEASONAL NORMS. BOTH GFS AND EURO CONTINUE NORTHWEST FLOW INTO THE LATER PORTION OF THE FORECAST WITH NEXT SYSTEM ARRIVING THURSDAY NIGHT INTO FRIDAY. THIS WILL BE THE NEXT APPRECIABLE THREAT OF CONVECTION WITH GFS TRYING TO LINGER ADDITIONAL STORMS INTO THE WEEKEND AS IT LEAVES THE FRONT IN VICINITY OF IA. EURO PUSHES THE BOUNDARY FARTHER SOUTH WITH RELATIVELY TRANQUIL WEATHER FOR NEXT WEEKEND. && .AVIATION...06/00Z ISSUED AT 549 PM CDT SUN JUL 6 2014 COLD FRONT ACROSS IA FROM NERN CORNER TO THE SWRN CORNER WILL MOVE SOUTHEAST AND BE SOUTHEAST OF THE TAF SITES BY 06Z. SCATTERED LINE OF THUNDERSTORMS ALONG THE FRONT WILL BE AROUND THE ERN TAF SITES EARLY THIS EVENING. WITH LIGHT WINDS OVERNIGHT...EXPECT TO SEE SOME MVFR FOG CONDITIONS DEVELOP AROUND SUNRISE. LIGHT WINDS AND VFR CONDITIONS ON MONDAY. OUTLOOK...SECOND COLD FRONT WILL MOVE INTO THE STATE MONDAY NIGHT INTO EARLY TUE. EXPECT TO SEE WIDESPREAD THUNDERSTORM DEVELOPMENT...ESPECIALLY OVER THE SRN THIRD OF THE STATE MONDAY NIGHT WITH ACTIVITY MOVING OUT TUE. HIGH PRESSURE WILL BRING VFR CONDITIONS WED THROUGH THU. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...REV LONG TERM...COGIL AVIATION...MS JUL 14
AREA FORECAST DISCUSSION
NWS DES MOINES IA
319 PM CDT SUN JUL 6 2014 .SHORT TERM /TONIGHT/... ISSUED AT 319 PM CDT SUN JUL 6 2014 CLOUDS TODAY CONTINUE TO COMPLICATE THIS EVENINGS CONVECTION CHANCES. LOW LEVEL STRATUS WHICH FORMED IN THE SOUTHERLY MOISTURE FEED ACROSS THE AREA HAVE KEPT TEMPERATURES ABOUT 5 TO 7 DEGREES COOLER THAN FORECAST. ALOFT WE ARE ALSO DEALING WITH A SUFFICIENT MID LEVEL CAP AT H700 WITH TEMPS FROM 10 TO 12C IN THE WARM SECTOR THAT HAS TENDED TO KEEP CONVECTION EAST OF THE AREA. COMBINED WITH RELATIVELY WEAK CONVERGENCE ALONG THE APPROACHING COOL FRONT... AFTERNOON CONVECTION HAS BEEN SLOW TO TAKE OFF ALONG THE BOUNDARY IN MN/WESTERN WI. BUFR SOUNDINGS SHOW THAT CAP SHOULD REMAIN IN PLACE ALONG AND WEST OF I35 THIS EVENING...WHILE ERODING EAST OF THAT LINE WITH THE HELP OF THE DEVELOPING CONVECTION WHICH SHOULD BUILD BACK WEST SOUTHWEST WITH TIME THROUGH 06Z. GENERALLY SCATTERED CONVECTION IS EXPECTED ACROSS THE AREA SINCE THE CAP ALOFT WILL BE STRONGER AS THE STORMS MOVE BACK WEST INTO IOWA. NEARLY ALL THE MODELS INCLUDING THE HRRR FAVOR THIS SCENARIO. SO...HAVE TRIMMED POP/THUNDERSTORM CHANCES FROM I35 WEST WITH THE EXCEPTION OF AREAS ALONG THE IA/MO BORDER WHERE LATE MID EVENING SOME RESIDUAL CONVECTION MAY LINGER ALONG THE BOUNDARY. AIRMASS OVER EASTERN AND NORTHERN IA STILL RATHER UNSTABLE AND ANY STORMS THAT BUILD BACK TO THE WEST WILL STILL HAVE A CHANCE TO PRODUCE SVR WIND GUSTS AND LARGE HAIL. .LONG TERM /MONDAY THROUGH SUNDAY/... ISSUED AT 319 PM CDT SUN JUL 6 2014 INITIALLY CONDITIONS ARE EXPECTED TO BE QUIET MONDAY MORNING WITH SURFACE BOUNDARY STALLED IN MO/KS. SHORTWAVE WILL BE RAPIDLY ADVANCING SOUTHEAST THROUGH THE NORTHERN PLAINS. MODELS ALL INDICATE SURFACE MOISTURE RETURNING WITH DEWPOINTS INTO THE U60S/L70S BY AFTERNOON. HOWEVER...BEST LOW LEVEL CONVERGENCE APPEARS TO REMAIN JUST SOUTH OF IOWA AND THIS WILL LIKELY BE THE FOCUS OF THE MOST INTENSE CONVECTION BY LATE AFTERNOON INTO MONDAY NIGHT. THIS CONVECTION WILL LIKELY IMPACT SOUTHWEST THIRD OR SO OF THE STATE WITH THE POTENTIAL FOR SEVERE WINDS AND LARGE HAIL. HEAVY RAINS WILL ALSO BE POSSIBLE ALTHOUGH THE FOCUS AGAIN MAY BE JUST SOUTH AND WEST OF THE STATE WHERE BEST LOW LEVEL CONVERGENCE IS EXPECTED TO OCCUR. OTHERWISE...STRONG MID LEVEL FORCING WILL PRODUCE CONVECTION FARTHER NORTHEAST THROUGH MUCH OF THE REMAINDER OF CENTRAL IOWA LATE MONDAY AFTERNOON/EVENING BUT WITH LESS COVERAGE. DRIER AIR WILL FITLER INTO THE STATE IN THE WAKE OF THE SYSTEM ON TUESDAY WITH RELATIVELY QUIET WEATHER INTO THE MIDDLE OF THE WEEK WITH TEMPERATURES AT OR BELOW SEASONAL NORMS. BOTH GFS AND EURO CONTINUE NORTHWEST FLOW INTO THE LATER PORTION OF THE FORECAST WITH NEXT SYSTEM ARRIVING THURSDAY NIGHT INTO FRIDAY. THIS WILL BE THE NEXT APPRECIABLE THREAT OF CONVECTION WITH GFS TRYING TO LINGER ADDITIONAL STORMS INTO THE WEEKEND AS IT LEAVES THE FRONT IN VICINITY OF IA. EURO PUSHES THE BOUNDARY FARTHER SOUTH WITH RELATIVELY TRANQUIL WEATHER FOR NEXT WEEKEND. && .AVIATION...06/18Z ISSUED AT 1238 PM CDT SUN JUL 6 2014 MAIN CONCERNS REMAIN THE LOW CLOUDS NORTH AND POTENTIAL FOR CONVECTION THIS AFTERNOON AND EVENING. OVERNIGHT MCS ACROSS MN CREATED A LARGE CI SHIELD WHICH HAS KEPT LOW ST FROM BURNING OFF THROUGH THE MORNING OVER THE NORTH. MVFR ST ALSO FORMED IN AREA OF MODEST LOW LEVEL MOISTURE ADVECTION OVER THE SOUTH CENTRAL. CIGS WILL LIFT MORE RAPIDLY THIS AFTERNOON...WITH INSTABILITY BUILDING WEST. OVER THE NORTHEAST CONVERGENCE ALONG THE BOUNDARY WOULD FAVOR SOME CONVECTION FOR KMCW...KALO THROUGH 00Z. ELSEWHERE...SOME CONCERNS THAT STRONG CAP SHOWING UP IN BUFR SOUNDINGS WILL HOLD FOR KDSM AND KOTM EVEN THIS AFTERNOON AND EVENING. CURRENT CONVECTION REMAINS WELL NORTH OF AREA ALONG BOUNDARY FROM WEST CENTRAL WI TO KMSP. WILL MONITOR FOR ANY EXPANSION INTO CENTRAL IOWA BUT FOR NOW...TRENDS SUGGEST NORTHEAST SECTIONS MOST AT RISK FOR DEVELOPMENT THIS AFTERNOON/EVENING. /REV && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...REV LONG TERM...COGIL AVIATION...REV
AREA FORECAST DISCUSSION
NWS GOODLAND KS
208 PM MDT SUN JUL 6 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 203 PM MDT SUN JUL 6 2014 NORTHERLY FLOW ON THE EAST SIDE OF A RIDGE OVER THE ROCKIES WILL CONTINUE ACROSS THE HIGH PLAINS TONIGHT AND MONDAY. A SURFACE TROUGH WILL BE ACROSS NORTHWEST KANSAS TONIGHT WITH A COLD FRONT POISED TO MOVE SOUTH INTO THE REGION MONDAY AFTERNOON. A SURFACE TROUGH DIVIDING GENERALLY THE NORTHWEST HALF OF THE FA FROM THE SOUTHEAST HALF WILL SERVE AS A FOCUS POINT FOR SOME ISOLATED CONVECTION THIS EVENING. CAPE IS AROUND 2000 J/KG ACROSS THE SOUTHEAST FA WITH INCREASING CIN ACROSS THE NORTHWEST. VERY WARM H7 TEMPERATURES WILL HAVE TO BE OVERCOME. FOR THIS REASON WILL KEEP POPS AT SLIGHT CHANCE FOR THIS EVENING. THERE ARE SOME TIMING DIFFERENCES FOR THE FRONT BETWEEN THE GFS AND NAM ON MONDAY. THE GFS IS LATER WITH PRECIPITATION ASSOCIATED WITH THE FRONT. FOR THIS REASON PLAN TO KEEP POPS LOWER MONDAY AFTERNOON. FORCING IS INDICATED BY BOTH MODELS BUT MOISTURE IS LESS THAN IDEAL DURING THE AFTERNOON. PLAN TO CONTINUE SLIGHT CHANCE AND CHANCE POPS MONDAY AFTERNOON. MIN TEMPERATURES TONIGHT WILL COOL TO THE MID AND UPPER 60S. MAX TEMPERATURES MONDAY WILL RISE TO THE MID AND UPPER 90S. COOLER LOWER 90S WILL BE FOUND ACROSS NORTHERN AREAS WHERE CLOUD COVER HAS INCREASED. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 203 PM MDT SUN JUL 6 2014 MONDAY NIGHT THROUGH TUESDAY NIGHT CHANCES FOR RAINFALL RETURN TO THE AREA. THE BEST CHANCE FOR RAINFALL WILL BE MONDAY EVENING AS A COLD FRONT MOVES SOUTH INTO THE AREA. BEHIND THE FRONT NORTHERLY WINDS WILL BECOME BREEZY AS A LOW LEVEL JET DEVELOPS AND FOLLOWS THE FRONT THROUGH THE AREA. SOUNDINGS SHOW A FAIRLY DRY ENVIRONMENT BELOW 600MB AS THE FRONT MOVES THROUGH...BUT SATURATE ABOVE THIS LAYER. IN ADDITION THETA-E LAPSE RATES ABOVE 600MB CONTINUE TO SUGGEST CONVECTIVE INSTABILITY AS THE FRONT MOVES THROUGH. DO NOT ANTICIPATE STRONG THUNDERSTORMS FORMING AS THE FRONT MOVES THROUGH DUE TO THE LACK OF CAPE. STORM MOTION WILL BE TO THE EAST SO LOCATIONS EAST OF HIGHWAY 25 WILL HAVE A BETTER SHOT AT RECEIVING RAINFALL. AFTER MIDNIGHT STORMS SHOULD MOVE OUT OF THE AREA AS THE LIFT DECLINES WITH THE FRONT SOUTH OF THE AREA. TUESDAY A HIGH PRESSURE AT 850MB MOVES ACROSS THE AREA. BEHIND THE RIDGE THE FRONT WILL MOVE BACK ACROSS THE AREA FROM THE WEST AS A WARM FRONT DURING THE AFTERNOON. SOUNDINGS SHOW SOME SURFACE CAPE TO WORK WITH BUT BASED ON THE SOUNDING PROFILES...DOUBT MORE THAN ISOLATED STORMS WILL DEVELOP ALONG THE FRONT OVER KIT CARSON/CHEYENNE COUNTIES. BY TUESDAY EVENING STORM COVERAGE MAY INCREASE OVER THE SOUTHWEST PART OF THE AREA ALONG THE STALLED FRONT. HOWEVER NOT TOO OPTIMISTIC OF STORM DEVELOP SINCE THE BEST SURFACE MOISTURE WILL BE SOUTHWEST OF THE AREA. STORM MOTION WILL BE TO THE EAST...SO THERE IS A POSSIBILITY STORMS MAY MOVE INTO KIT CARSON/CHEYENNE COUNTIES FROM THE WEST. STORMS SHOULD DIMINISH DURING THE LATE EVENING AS THE ENVIRONMENT STABILIZES. WEDNESDAY THROUGH SUNDAY NORTHWEST UPPER LEVEL FLOW WILL CONTINUE OVER THE AREA UNTIL FRIDAY WHEN THE UPPER LEVEL RIDGE OVER THE ROCKIES MOVES ONTO THE PLAINS. AN UPPER LEVEL TROUGH WILL FOLLOW THE RIDGE ACROSS THE PLAINS FRIDAY SO WILL CONTINUE WITH THE RAINFALL CHANCES FOR FRIDAY. OVERALL NOT VERY IMPRESSED WITH THE RAINFALL CHANCES FOR THIS TIME FRAME DUE TO THE RATHER BROAD NATURE OF THE TROUGHS MOVING THROUGH THE NORTHWEST FLOW DUE TO THE CLOSE PROXIMITY OF THE RIDGE. RAINFALL CHANCES LOOK BETTER SUNDAY WHEN A STRONG UPPER LEVEL SHORT WAVE TROUGH MOVES ACROSS THE AREA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1116 AM MDT SUN JUL 6 2014 VFR CONDITIONS WILL CONTINUE AT KGLD AND KMCK FOR THE NEXT 24 HOURS. HOWEVER, THERE IS A SLIGHT CHANCE OF THUNDERSTORMS AT KGLD AND KMCK AROUND 00Z MONDAY. THE HRRR MODEL INDICATES A FEW STORMS NEAR BOTH SITES AND THIS SEEMS REASONABLE WITH A TROUGH AND COLD FRONT NEAR KMCK FOR STORMS TO INITIATE ON. ALSO UP SLOPE FLOW INTO THE HIGHER TERRAIN OF COLORADO MAY PRODUCE A FEW STORMS THAT WILL MOVE EAST ACROSS THE KANSAS BORDER INTO THE KGLD AREA. STORMS WILL BE BRIEF WITH CLEARING OVERNIGHT. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...FS LONG TERM...JTL AVIATION...FS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1120 AM MDT SUN JUL 6 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 355 AM MDT SUN JUL 6 2014 HOT TEMPERATURES WILL CONTINUE TODAY WITH A BROAD AREA OF HIGH PRESSURE IN PLACE ACROSS THE WESTERN UNITED STATES. CONDITIONS WILL BE MOSTLY DRY...ALTHOUGH WITH TEMPERATURES IN THE EAST AROUND 100 DEGREES WITH DEWPOINTS AROUND 60 DEGREES...THERE WILL BE A SLIGHT CHANCE OF THUNDERSTORMS DEVELOPING IN THE SURFACE CONVERGENT AREA NEAR THE SURFACE THROUGH EXPECTED TO BE POSITIONED ACROSS THE FORECAST AREA LATE TODAY AND THIS EVENING. THE APEX OF THE UPPER RIDGE SHARPENS OVER THE PACIFIC NORTHWEST TONIGHT AS A SHORT WAVE TROUGH SLIDES DOWN THE EAST SIDE OF THE NORTHWEST FLOW OF THE INCREASING AMPLITUDE PATTERN. THIS SHORT WAVE TROUGH IS EXPECTED CLIP THE CENTRAL HIGH PLAINS REGION MONDAY NIGHT AND HELP PUSH A COLD FRONT THROUGH THE FORECAST AREA. SKY COVER WILL INCREASE ACROSS THE REGION...KEEPING THE NORTHERN SECTIONS OF THE FORECAST AREA A FEW DEGREES COOLER THAN ON SUNDAY. ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED ACROSS THE FORECAST AREA LATE MONDAY AFTERNOON THROUGH MONDAY EVENING WITH A GREATER COVERAGE OF STORMS ACROSS THE NORTHEAST IN CLOSER PROXIMITY TO THE UPPER SHORT WAVE TROUGH. THERE IS A SLIGHT RISK OF SEVERE STORMS WITH LARGE HAIL BEING THE MAIN THREAT. COOLER TEMPERATURES CLOSER TO THE AVERAGE OF THIS TIME OF YEAR ARE EXPECTED ON TUESDAY IN THE WAKE OF THE COLD FRONT AS HIGH PRESSURE MOVES IN AT THE SURFACE. THE COLD FRONT MAY GET HUNG UP ALONG THE FRONT RANGE OF COLORADO AND EXTEND INTO THE VICINITY OF THE PANHANDLE REGION...SO THERE IS A POSSIBILITY OF ANOTHER ROUND OF THUNDERSTORMS ACROSS MAINLY THE SOUTHWEST PORTIONS OF THE FORECAST AREA LATE TUESDAY AFTERNOON AND EVENING AS ADDITIONAL IMPULSES MOVE THROUGH THE NORTHWEST FLOW ALOFT. .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 355 AM MDT SUN JUL 6 2014 A FAIRLY SEASONABLE PATTERN THROUGH LATE NEXT WEEK INTO THE WEEKEND. AN UPPER HIGH/RIDGE WILL EVOLVE OVER THE GREAT BASIN REGION DURING THIS PERIOD PROVIDING GENERALLY NORTHWEST FLOW AT UPPER LEVELS. SOME MODEL DISAGREEMENT ON THE EVOLUTION OF THIS RIDGE OVER THE WEEKEND...WITH THE ECMWF QUICK TO BUILD ANOTHER RIDGE TO THE WEST WHILE THE GFS/GEFS KEEP A NEARLY-FLAT RIDGE OVER THE CENTRAL PLAINS DURING THE WEEKEND. AT LOW LEVELS FLOW WILL BE OUT OF THE SOUTH...BRINGING WARM AND MOIST GULF AIR INTO THE REGION. AT THE SURFACE MAY HAVE A WEAK WARM FRONT MOVE UP ACROSS THE AREA THURSDAY AFTERNOON...AND IT LOOKS LIKELY A COLD FRONT WILL BE APPROACHING FROM THE NORTH LATE SATURDAY. OTHERWISE WILL RELY ON TERRAIN AND SMALLER-SCALE OUTFLOW FEATURES TO SERVE AS A FOCUS FOR STORMS EACH DAY. THIS PERIOD IS APPROACHING THE HOTTEST TIME OF THE YEAR /JULY 13-15 BASED ON 1982-2010 NORMALS/ AND AT THIS POINT IT DOES NOT APPEAR WE WILL BE TOO FAR OFF FROM NORMAL /90.3 TO 90.5 ACROSS THE EXTENDED FORECAST PERIOD/. TEMPS EACH DAY WILL BE IN THIS RANGE...WITH THE HOTTEST DAY LOOKING LIKE THURSDAY OR FRIDAY WHEN 850MB TEMPS WILL BE IN THE LOW 30S C...INDICATIVE OF HIGHS IN THE MID 90S WITH THE POSSIBILITY OF A FEW SPOTS REACHING TRIPLE DIGITS. LOWS WILL IN THE MID TO UPPER 60S...EXCEPT ALONG/EAST OF HIGHWAY 83 WHERE LOWS ARE MORE LIKE THE LOW 70S. AM NOT PARTICULARLY EXCITED ABOUT PRECIP CHANCES DURING THE PERIOD DUE TO THE INHIBITION PROVIDED BY THE VERY WARM LOW/MID LEVELS /700MB TEMPS OVER 14C MOST OF THE TIME/. BEST CHANCE FOR STORMS LOOKS TO BE WEDNESDAY AFTERNOON/EVENING. WILL HAVE OVER 1500 J/KG MUCAPE AVAILABLE WITH AROUND 40 KTS OF EFFECTIVE SHEAR. T-TD SPREAD AT THE SURFACE WILL BE AROUND 25 DEG F...WHICH COULD LEAD TO SOME GUSTY THUNDERSTORMS. STORM MOTIONS WILL BE 5 TO 10KTS...NOT PARTICULARLY FAST...BUT PWATS HAVE TRENDED LOW IN RECENT MODEL RUNS /NOW IN THE 1.2 TO 1.4 INCH RANGE INSTEAD OF THE 1.5-PLUS RANGE/ SO HEAVY RAINFALL MAY NOT BE AS BIG OF A CONCERN AS FIRST THOUGHT. UPPER FORCING WILL BE PROVIDED BY WAY OF MID-LEVEL SHORTWAVE TROUGH THAT MOVES ACROSS CENTRAL ROCKIES...AND FOCUS FOR CONVECTION WILL BE MOSTLY TERRAIN-BASED WITH PERHAPS A FEW CELLS FORMING ALONG A WEAK SURFACE TROUGH ACROSS THE COLORADO PLAINS. FOR THE REST OF THE WEEK...PRECIP CHANCES ARE MARGINAL THURS/FRI DUE TO CAPPING AND RELATIVELY WEAK DISTURBANCES THAT MOVE ACROSS THE REGION...THOUGH THUNDERSTORM ACTIVITY FROM WEDNESDAY MAY MODIFY THE ENVIRONMENT TO BETTER SUPPORT STORMS DURING THESE DAYS. WIND SHEAR WILL BE MUCH LESS SUPPORTIVE OF ORGANIZED STORMS...AND THUS EXPECT MORE WEAK TERRAIN-BASED AND PULSE STORMS. SATURDAY DO EXPECT STORMS ASSOCIATED WITH THE APPROACHING COLD FRONT...THOUGH LAPSE RATES ARE NOT VERY STEEP...SO STRONG THUNDERSTORM DEVELOPMENT DOES NOT APPEAR LIKELY AT THIS POINT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1116 AM MDT SUN JUL 6 2014 VFR CONDITIONS WILL CONTINUE AT KGLD AND KMCK FOR THE NEXT 24 HOURS. HOWEVER, THERE IS A SLIGHT CHANCE OF THUNDERSTORMS AT KGLD AND KMCK AROUND 00Z MONDAY. THE HRRR MODEL INDICATES A FEW STORMS NEAR BOTH SITES AND THIS SEEMS REASONABLE WITH A TROUGH AND COLD FRONT NEAR KMCK FOR STORMS TO INITIATE ON. ALSO UPSLOPE FLOW INTO THE HIGHER TERRAIN OF COLORADO MAY PRODUCE A FEW STORMS THAT WILL MOVE EAST ACROSS THE KANSAS BORDER INTO THE KGLD AREA. STORMS WILL BE BRIEF WITH CLEARING OVERNIGHT. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...LOCKHART LONG TERM...JJM AVIATION...FS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
639 PM EDT SUN JUL 6 2014 .SYNOPSIS... A WEAK DISTURBANCE WILL MOVE ACROSS THE REGION TONIGHT. UNSETTLED CONDITIONS ARE THEN EXPECTED MONDAY THROUGH MID WEEK. && .NEAR TERM /THROUGH MONDAY/... 640 PM UPDATE...INCREASED THE RAIN CHANCES TO 60% FOR THE NORTHERN AREAS AS THE LATEST RADAR LOOP SHOWED AN AREA OF SHOWERS EXTENDING FROM WESTERN MAINE ESE INTO NE MAINE. THIS AREAS OF SHOWERS WAS DUE TO A DISTURBANCE MOVING ACROSS NORTH-CENTRAL MAINE AS SEEN ON THE LATEST WV SATELLITE LOOP. TEMPERATURES HAVE COOLED BACK INTO THE LOW TO MID 60S DUE TO THE CLOUDS AND SHOWERS WHILE S OF THE FRONT, READINGS WERE WELL INTO THE 70S. THE LATEST HRRR AND RUC BOTH MATCHED UP CLOSE W/THIS SETUP AND SHOWED SOME LIGHT SHOWER ACTIVITY EXTENDING FURTHER S INTO PORTIONS AND CENTRAL AND EASTERN AREAS. THEREFORE, ADDED A MENTION FOR A SHOWERS IN THESE AREAS THROUGH THE EVENING. THE FRONT IS FORECAST TO LIFT N OF THE AREA OVERNIGHT W/SHOWERS PULLING OUT OF THE AREA. PREVIOUS DISCUSSION... A WEAK DISTURBANCE MOVING ACROSS NORTHERN MAINE HAS BROUGHT MOSTLY CLOUDY SKIES TO THE NORTH. THIS WEAKER SYSTEM HAS ALSO BROUGHT SOME SHOWERS MAINLY ACROSS FAR NORTH AND NORTHWEST PORTIONS OF THE FORECAST AREA. THESE SHOWERS WILL SLOWLY DRIFT EAST TO SOUTHEAST ACROSS THE CENTRAL AND NORTHERN PARTS OF THE FORECAST AREA THIS AFTERNOON INTO TONIGHT. THIS HAS SUPPRESSED TEMPERATURES ACROSS THE NORTH WHILE THOSE ACROSS SOUTHERN PORTIONS OF THE FORECAST AREA HAVE ENJOYED MORE SUNSHINE WITH PARTLY TO MOSTLY SUNNY SKIES AND WARMER TEMPERATURES. THIS DISTURBANCE WILL KEEP INCREASED SHOWER CHANCES ACROSS THE FAR NORTH TONIGHT WHILE SOUTHERN PORTIONS OF THE REGION ARE EXPECTED TO STAY DRY. A FRONTAL BOUNDARY WILL APPROACH THE REGION AS WE GO INTO MONDAY. THIS WILL BRING A INCREASED CHANCE OF SHOWERS AND THUNDERSTORMS TO THE REGION AS WE GO INTO MONDAY AFTERNOON. BEST CHANCES OF SHOWERS AND THUNDERSTORMS WILL BE ACROSS THE NORTHERN AND NORTHWESTERN PORTIONS OF THE FORECAST AREA. LOW TEMPERATURES ACROSS THE REGION TONIGHT ARE EXPECTED TO BE IN THE UPPER 50S TO LOWER 60S WITH HIGH TEMPERATURES MONDAY GENERALLY IN THE UPPER 70S TO LOWER 80S. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... A WEAKENING COLD FRONT/TROF WILL BEGIN TO CROSS THE REGION MONDAY NIGHT. EXPECT A WEAKENING AREA OF SHOWERS/THUNDERSTORMS TO MOVE SOUTH ACROSS THE FORECAST AREA MONDAY NIGHT. THE REMNANTS OF THIS BOUNDARY AND DIURNAL HEATING COULD PRODUCE A CHANCE OF SHOWERS/THUNDERSTORMS TUESDAY. ANOTHER COLD FRONT WILL BEGIN TO CROSS THE REGION TUESDAY NIGHT INTO WEDNESDAY...THOUGH THE EXACT TIMING OF THE FRONT IS STILL UNCERTAIN. EXPECT A CHANCE OF SHOWERS/THUNDERSTORMS WITH THIS FRONT...THOUGH THE EXTENT OF COVERAGE IS ALSO STILL UNCERTAIN DEPENDENT ON THE EVENTUAL TIMING OF THE FRONT. TEMPERATURES WILL BE AT SLIGHTLY ABOVE NORMAL LEVELS TUESDAY/WEDNESDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... A COLD FRONT EXITS MAINE WEDNESDAY NIGHT WITH SHOWERS COMING TO AN END. AN UPPER LEVEL TROUGH FILLS ON THURSDAY AND FRIDAY THEN GIVES WAY TO RIDGING FOR THE WEEKEND. DRY AND SLIGHTLY ABOVE NORMAL TEMPERATURES CAN BE EXPECTED. A SHORTWAVE TROUGH MOVES INTO THE NORTHEAST U.S. ON SUNDAY WITH A COLD FRONT SWEEPING ACROSS MAINE. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE WITH THE FRONTAL PASSAGE. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... NEAR TERM: SITES WILL STAY MOSTLY VFR WITH NORTHERN SITES GOING MVFR WITH DISTURBANCE AND SHOWERS MOVING ACROSS THE REGION TONIGHT. SOME SITES COULD BE REDUCED ONCE AGAIN ACROSS THE NORTH IN HEAVIER SHOWERS AND THUNDERSTORMS MONDAY. SHORT TERM: OCCASIONAL MVFR/IFR CONDITIONS WILL OCCUR ACROSS THE REGION MONDAY NIGHT WITH SHOWERS AND THUNDERSTORMS. GENERALLY VFR CONDITIONS ARE EXPECTED ACROSS THE REGION TUESDAY INTO THURSDAY AWAY FROM ANY SHOWERS OR THUNDERSTORMS...WITH VARIABLE CONDITIONS IN THE VICINITY OF SHOWERS OR THUNDERSTORMS. VFR CONDITIONS ARE EXPECTED FRIDAY. && .MARINE... NEAR TERM: NO HEADLINES HAVE BEEN ISSUED AT THIS POINT. HOWEVER SEAS ARE EXPECTED TO BUILD FROM 3 TO 5 FT TO 4 TO 6 FT LATER MONDAY DUE TO INCREASED SW FLOW. SHORT TERM: SMALL CRAFT ADVISORY LEVEL SEAS ARE POSSIBLE MONDAY NIGHT INTO WEDNESDAY NIGHT. VISIBILITIES COULD BE REDUCED AT TIMES IN SHOWERS MONDAY NIGHT INTO WEDNESDAY NIGHT. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...HEWITT/JORDAN SHORT TERM...NORCROSS LONG TERM...OKULSKI AVIATION...HEWITT/JORDAN/NORCROSS MARINE...HEWITT/JORDAN/NORCROSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
427 PM EDT SUN JUL 6 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 426 PM EDT SUN JUL 6 2014 WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW DOWNSTREAM FROM A RIDGE OVER THE ROCKIES AND WRN PLAINS. A PROMINENT SHORTWAVE TROUGH EXTENDED FROM NW ONTARIO TO WRN LAKE SUPERIOR. A COLD FRONT EXTENDED INTO NE MN FROM LOW PRESSURE NEAR CYPL. EXTENSIVE CLOUDS COVER OVER THE REGION HAS INHIBITED DIABATIC HEATING AND KEPT MLCAPE VALUES IN THE 500-1000 J/KG RANGE OVER MAINLY THE WRN THIRD OF UPPER MI. AN AREA OF SHRA/TSRA OVER NE WI NEAR TO IMT AND NEAR MNM WAS SUPPORTED BY WEAK TO MODERATE 700-300 MB QVECTOR CONV AND 30 KNOT WSW 850-750 INFLOW PUSHING MUCAPE VALUES TO 1K J/KG. ADDITIONAL STRONG TSRA WERE LOCATED OVER NE MN WERE LOCATED NEAR THE COLD FRONT. LATE THIS AFTERNOON INTO TONIGHT...WITH SOME LATE AFTERNOON CLEARING OVER WRN UPPER MI...ADDITIONAL HEATING MAY BOOST MLCAPE VALUES INTO THE 1000-1500 J/KG RANGE. AS THE COLD FRONT SWEEPS INTO THE AREA BTWN 21Z-24Z...SCT/NMRS TSRA ARE EXPECTED TO DEVELOP THAT COULD BE STRONG TO SEVERE...SUPPORTED BY 0-6KM SHEAR VALUES IN THE 35-40 KNOT RANGE. THE SHRA/TSRA WILL THEN SHIFT INTO THE ERN CWA BTWN 00Z-03Z AND END OVER THE CNTRL CWA...AS THE COLD FRONT ADVANCES. EXPECT CLEARING OVERNIGHT AS SUBSIDENCE AND DRIER AIR MOVE IN FROM THE WEST. MONDAY...EXPECT DRY AND BREEZY CONDITIONS WITH TEMPERATURES CLIMBING TO NEAR SEASONAL NORMALS IN THE MID 70S TO AROUND 80. A SLIGHT CHANCE FOR SHRA/TSRA WAS INCLUDED OVER THE FAR SW CWA AS A WEAK SHRTWV NEAR THE AREA IN CYCLONIC MID LEVEL FLOW AROUND THE TROUGH OVER NRN MANITOBA AND NRN ONTARIO. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 337 PM EDT SUN JUL 6 2014 A SHORTWAVE TROUGH WILL MOVE NEAR OR OVER THE CWA MON NIGHT INTO TUE MORNING...WITH TYPICAL MODEL DISAGREEMENT ON MAGNITUDE AND PATH OF THE SHORTWAVE AND ASSOCIATED CONVECTION. THERE IS SOME MODEL CONSENSUS THAT THE SHORTWAVE WILL BE ALONG OR S/SW OF THE WRN AND SRN PORTIONS OF THE CWA...SO HAVE CONTINUED TO FAVOR THESE LOCATIONS FOR THE BEST POPS MON NIGHT INTO TUE MORNING. CONTINUED TO ONLY HAVE CHANCE POPS DUE TO LIMITED MOISTURE. ANOTHER SHORTWAVE DIVES ACROSS OR NEAR THE CWA TUE AFTERNOON/EVENING...BUT MOISTURE WILL BE EVEN MORE LIMITED THAN WITH THE PREVIOUS SHORTWAVE...SO CONTINUED THE FORECAST OF EVEN LOWER POPS /SLIGHT CHANCE TO LOW END CHANCE/ DURING THIS TIME. YET ANOTHER SHORTWAVE LOOKS TO MOVE THROUGH LATE TUE NIGHT INTO WED. MOISTURE CONTINUES TO BE MORE LIMITED WITH TIME...SO ONLY HAVE SLIGHT CHANCE POPS DURING THIS PERIOD. NO PRECIPITATION EXPECTED FROM WED NIGHT THROUGH MUCH OF FRI AS UPPER RIDGING BUILDS OVER THE REGION. AFTER RELATIVELY COOL WEATHER TUE AND WED WITH HIGHS IN THE 60S TO LOW 70S...THE RIDGE WILL BRING A WARMING TREND AS HIGH TEMPS CLIMB INTO THE UPPER 70S /OR EVEN THE LOW 80S/ INLAND ON FRI. MODELS SHOW A TROUGH MOVING THROUGH THE REGION LATE FRI THROUGH SAT...WHICH WOULD LEAD TO SHOWERS AND THUNDERSTORMS ACROSS MUCH OF THE AREA. SUN COULD SEE SOME PRECIP IF THE ECMWF FORECAST VERIFIES IN BRINGING A SHORTWAVE NEAR THE CWA...BUT THE GFS HAS A DRY FORECAST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 154 PM EDT SUN JUL 6 2014 SOME EARLY AFTERNOON LOW CLOUDS AT SAW WILL GIVE WAY TO MVFR CIGS WITH MID CLOUDS THIS AFTERNOON. THE APPROACH OF A COLD FRONT AND DISTURBANCE IS EXPECTED TO PRODUCE SCT/NMRS SHRA/TSRA BY MID AFTERNOON OVER WRN UPPER MI AND LATE THIS AFTERNOON INTO CNTRL UPPER MI. SOME STRONGER STORMS WITH GUSTY WINDS AND HAIL MAY BE POSSIBLE. HOWEVER...WITH UNCERTAINTY WITH THE COVERAGE/POSITION...ONLY VCTS WAS MENTIONED. BEHIND THE FRONT...DRY ADVECTION WILL BRING IMPROVEMENT TO VFR CONDITIONS THIS EVENING. GUSTY WNW WINDS WILL DEVELOP LATE TONIGHT AT CMX AND MON MORNING AT IWD/SAW. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 406 AM EDT SUN JUL 6 2014 FOG WILL CONTINUE ACROSS LAKE SUPERIOR INTO MONDAY. WINDS ARE EXPECTED TO BE BELOW 25KTS THROUGH THE PERIOD /OUTSIDE OF ANY STRONG SHOWERS OR THUNDERSTORMS/. LOW PRESSURE ACROSS N MINNESOTA AND W ONTARIO WILL DEEPEN SLIGHTLY OVER CENTRAL ONTARIO AND N LAKE SUPERIOR THIS EVENING...BEFORE MOVING ACROSS QUEBEC ON MONDAY. BRIEF HIGH PRESSURE WILL SLIDE ACROSS LAKE SUPERIOR MONDAY NIGHT...AS WEAK LOW PRESSURE PUSHES ACROSS LAKE MICHIGAN AND LAKE HURON ON TUESDAY. ANOTHER WEAK LOW ACROSS ONTARIO TUESDAY NIGHT IS EXPECTED TO SINK ACROSS LAKE SUPERIOR ON WEDNESDAY...BEFORE STRONGER HIGH PRESSURE SETTLES ACROSS THE UPPER GREAT LAKES WEDNESDAY NIGHT THROUGH AT LEAST THURSDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...JLB MARINE...KF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
352 PM CDT SUN JUL 6 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 328 PM CDT SUN JUL 6 2014 COLD FRONT HAS BEEN MAKING STEADY PROGRESS TO THE EAST AT ABOUT 20 KTS ACROSS MN TODAY...AND AT 3PM WAS IN THE PROCESS OF WORKING ACROSS THE TWIN CITIES. MORNING CLOUDS SLOWED DOWN THE WARMING IN THE TWIN CITIES...BUT THERE IS STILL HOPE FOR OUR FIRST 90 DEGREE TEMP THIS YEAR AS THERE WILL BE ABOUT A 2 HOUR WINDOW WHERE WE CAN STILL WARM BEHIND THE FRONT BEFORE THE CAA KICKS IN. WE HAVE SEEN PLACES LIKE REDWOOD FALLS...GLENCOE...AND NEW ULM HIT 90 IN THIS ZONE AND IT WILL BE HITTING THE TWIN CITIES STILL DURING PEAK HEATING BETWEEN 3 AND 5 PM...SO DON/T GIVE UP HOPE ON THAT FIRST 90 JUST YET! AS FOR STORM POTENTIAL...ACTIVITY OVER WI HAS BEEN ELEVATED...WITH THE ATMO STILL CAPPED WITH RESPECT TO SFC BASED CONVECTION PER THE STABLE CU FIELD /AT 230 PM/ STILL IN PLACE OVER WHAT IS A VERY JUICY WARM SECTOR...WHERE DEWPS HAVE BEEN COMMONLY RISEN UP INTO THE MID 70S. STILL LOTS OF DISAGREEMENT WITH WHETHER OR NOT THIS FRONT WILL EVEN GENERATE CONVECTION...BUT GIVEN THE DEGREE OF INSTABILITY PRESENT...ALONG WITH THE SHORTWAVE MOVING INTO WRN MN AS EVIDENCED BY DRYING ON WATER VAPOR BACK ACROSS THE DAKOTAS...PREFER THE IDEA THE HRRR AND MEMBER1 OF THE 15Z HOPWRF SHOW WITH A SCT LINE OF STORMS DEVELOPING ALONG THE FRONT AROUND 20Z AND QUICKLY SPREADING EAST. THIS WOULD PLACE THE THUNDER THREAT MAINLY ALONG AND EAST OF AN ALBERT LEA TO RICE LAKE LINE. SFC WINDS HAVE VEERED CONSIDERABLY DURING THE DAY...WHICH WILL RESULT IN A MINIMAL TORNADO THREAT...BUT 2K-4K J/KG OF MLCAPE...H7-H5 LAPSE RATES UP OVER 7 DEG C/KM...AND EFFECTIVE SHEAR AROUND 40 KTS WILL BE MORE THAN ENOUGH TO SUPPORT A WIND/HAIL THREAT...ESPECIALLY TOWARD THE IOWA BORDER WHERE INSTABILITY AND LAPSE RATES ARE BETTER. WILL SEE SKIES CLEAR OUT TONIGHT...BUT CONSISTENT NW WINDS WILL BRING IN DEWPS IN THE LOWER/MID 60S...WHICH WILL LIMIT THE FOG POTENTIAL. IN ADDITION...A VERY POTENT SHORTWAVE CURRENTLY OVER NRN SASKATCHEWAN WILL DROP INTO NODAK TONIGHT...WITH ACTIVITY EXPECTED TO DEVELOP OVER CENTRAL NODAK THIS EVENING. THIS WILL LIKELY SEND SHOWERS/STORMS TOWARD CENTRAL MN LATE TONIGHT INTO MONDAY MORNING...THOUGH MORE ROBUST STORM COVERAGE OVER THE MPX CWA IS NOT EXPECTED UNTIL MONDAY AFTERNOON AS THAT STRONG SASKATCHEWAN WAVE MOVES INTO WRN MN. FOR THIS WAVE...PREFERRED A GEM/ECMWF/GFS BLEND FOR ITS TIMING. THE NAM IS ABOUT 6 HOURS FASTER WITH THE WAVE...PLACING IT OVER ERN MN BY THE END OF THE SHORT TERM AS OPPOSED TO WRN MN AS THE OTHER GUIDANCE SHOWS. DETERMINISTIC MODELS SHOW FAIRLY WIDESPREAD CONVECTION DEVELOPING BASED ON THEIR QPF FIELDS...BUT THE CAMS SHOW ACTIVITY BEING NOTICEABLY MORE SCATTERED OVER MN MONDAY AFTERNOON. THIS IS LIKELY DUE TO THE FACT THAT THERE REALLY IS NO STRONG SFC FEATURE TO FOCUS ACTIVITY DURING THE AFTERNOON...SO THE CAMS ARE SIMPLY GENERATING CONVECTION WHERE THEY CAN DEVELOP ENOUGH INSTABILITY. THOUGH NW FLOW IS EXPECTED...1.5-2.5K J/KG OF MLCAPE COMBINED WITH 50-60 KTS OF BULK SHEAR WILL BE MORE THAN ENOUGH TO SUPPORT A SEVERE THREAT. HODOGRAPHS FOR MONDAY ARE MOSTLY LONG STRAIGHT LINES...INDICATING THE MAIN THREAT WOULD BE LARGE HAIL FROM SPLITTING SUPERCELLS. IF ENOUGH STORMS CAN INITIATE...WE WOULD LIKELY END UP WITH A COMPLEX OF STORMS OR TWO THAT WOULD HAVE A WIND TREAT AS WELL. HIGHER LCLS /DUE TO THE DRIER BOUNDARY LAYER AIR EXPECTED/ ALONG WITH THE SHEAR BEING MAINLY OF THE SPEED VARIETY /WITH LITTLE DIRECTION CHANGE/ WILL GREATLY LIMIT ANY TORNADO THREAT. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 328 PM CDT SUN JUL 6 2014 WHILE THE BEST STORM COVERAGE SHOULD GENERALLY BE BETWEEN 21-00Z IN WESTERN MN...EASTERN MN WILL HAVE THE BEST SHOT AT THUNDER BETWEEN 00-03Z...AND SHORTLY THEREAFTER IN WESTERN WI. THE MID- LEVEL DRYING ARRIVES QUICKLY BETWEEN 03-06Z IN THE EASTERN FORECAST AREA...SO THE PRECIP SHOULD GET QUICKLY SHUFFLED OFF TO THE EAST LATE TOMORROW EVENING. DRIER AND SLIGHTLY COOLER AIR ARRIVES BEHIND THE STORM SYSTEM ON TUESDAY WITH SURFACE HIGH PRESSURE EXPANDING INTO THE PLAINS AND UPPER LEVEL NORTHWEST FLOW. NORTHWEST WINDS WILL BE A LITTLE BREEZY...OTHERWISE EXPECT MOSTLY SUNNY SKIES AND MILD TEMPERATURES IN THE 70S TO NEAR 80 DEGREES. UPPER LEVEL RIDGING FLATTENS AS IT SHIFTS INTO THE HIGH PLAINS ON WEDNESDAY...HOWEVER WITH RETURN FLOW DEVELOPING IN WESTERN MN IN THE AFTERNOON HIGH TEMPERATURES WILL IMPROVE A FEW DEGREES. THE EAST WILL REMAIN ON THE FRINGE OF AN 850MN COLD POCKET CENTERED ROUGHLY OVER LAKE SUPERIOR. MID AND HIGH CLOUDS BUILDING INTO THE AREA FROM THE WEST. MODEL CONSISTENCY ISN`T AS GOOD LATER IN THE WEEK WITH WEST TO NORTHWEST UPPER FLOW AND THE POSSIBILITY OF A FEW WEAK WAVES TO TRACK THROUGH THE AREA. THE TIMING OF THESE WAVES REMAIN TOO DIFFICULT TO PINPOINT WITH EACH MODEL SHOWING SLIGHTLY DIFFERENT TIMING AND LATITUDINAL PLACEMENT - DID NOT REALLY ALTER THE POPS MUCH WEDNESDAY NIGHT AND BEYOND. TEMPERATURES ARE EXPECTED TO REMAIN WITHIN A FEW DEGREES OF CLIMATE NORMALS DURING THE PERIOD. AFTER MONDAY...THE NEXT SUBSTANTIAL PROBABILITY FOR PRECIP ARRIVES ON THURSDAY WHEN THE FLOW BECOMES A LITTLE MORE W-SW AND WARM ADVECTION ARRIVES FROM THE DAKOTAS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1243 PM CDT SUN JUL 6 2014 COLD FRONT MAKING STEADY PROGRESS ACROSS MN THIS AFTERNOON AND AT 18Z STRETCHED FROM ABOUT MILLE LACS LAKE DOWN TO WORTHINGTON...SO JUST ABOUT READY TO MOVE INTO THE WRN TWIN CITIES METRO AREA. SCT STORMS OVER WRN WI ARE ELEVATED...WITH SFC BASED STORMS EXPECTED TO DEVELOP ALONG THE COLD FRONT AROUND 20Z. BY THEN THE FRONT WILL LIKELY BE JUST CLEARING MSP AND NEARING RNH...SO STILL LOOKS LIKE FIELD WITH BEST CHANCE FOR TS WITH THE FROPA THIS AFTERNOON IS EAU...WHERE A VCTS WAS MAINTAINED...BUT SHIFTED AN HOUR LATER TO BETWEEN 21Z AND 23Z. TONIGHT IS EXPECTED TO BE QUIET...WITH VFR CONDS AND WNW-NW WINDS PREVAILING. OVERNIGHT...STORMS ARE EXPECTED TO DEVELOP OVER CENTRAL NODAK...WITH REMNANTS OF THAT ACTIVITY LIKELY DRIFTING INTO CENTRAL MN LATE TONIGHT/EARLY MON MORNING. CONFIDENCE ON HOW THIS POTENTIAL ACTIVITY WILL EVOLVE IS LOW...SO STUCK WITH NOTHING MORE THAN A VCSH TOWARD THE END OF THE AXN/STC TAFS. MORE ROBUST TSRA ACTIVITY ACROSS THE MPX AREA IS EXPECTED AFTER 18Z MON AS A STRONG SHORTWAVE COMES OUT OF THE DAKOTAS. KMSP...LOOKS LIKE SFC BASED CONVECTION ALONG THE COLD FRONT WILL START TO DEVELOP JUST AS THE FRONT IS CLEARING MSP...SO ACTIVITY THIS AFTERNOON WILL REMAIN EAST OF THE FIELD. NEXT CHANCE FOR PRECIP WOULD COME BETWEEN 12Z AND 16Z MON MORNING AND THAT WOULD BE ASSOCIATED WITH ANY REMNANTS OF STORMS THAT ARE EXPECTED TO DEVELOP OVER NODAK TONIGHT. AT THIS POINT...SPREAD IN MODELS IS HIGH ENOUGH TO KEEP ANY PRECIP MENTION OUT OF THE TAF MON MORNING. BETTER TSRA CHANCES EXPECTED MON AFTERNOON AS A STRONG SHORTWAVE MOVES INTO WRN MN. FAVORED THE TIMING OF THE GFS/ECMWF/GEM WITH A SLOWER PROGRESSION OF THE WAVE AND RESULTANT SLOWER ARRIVAL OF AFTERNOON ACTIVITY THAN WHAT THE NAM HAS. ONCE THESE PESKY LOW CLOUDS CLEAR OUT TODAY...CONFIDENCE IS HIGH IN REST OF TAF BEING VFR OUTSIDE OF ANY PRECIP. /OUTLOOK FOR KMSP/ TUE...VFR. WIND NW 10 TO 20 KT. WED...VFR. WIND NW 5 TO 15 KT. THU...VFR. CHC TSRA OVERNIGHT. WIND S 10 TO 15 KT. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...MPG LONG TERM...CLF AVIATION...MPG
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
304 PM CDT Sun Jul 6 2014 .SHORT TERM: (Through Late Tonight) Issued at 302 PM CDT Sun Jul 6 2014 (Tonight) Still expect thunderstorms to redevelop along the cold front where MLCAPES are 5000+ J/kg across Iowa. These storms should move southeast into the northern half of the CWA during the late evening and overnight hours as both the NAM/GFS are in good agreement that shortwave trough currently over the upper Midwest will move in sync with the cold front across the CWA tonight. Latest runs of HRRR are showing that storms will dissipate before reaching the CWA, but the amount of forcing and instability warrant keeping at least the chance pops already going in the forecast. The simulated reflectivity of the explicit runs of the WRF show a line of storms moving southward across the entire CWA between 02-08Z. Also can`t rule out a few severe thunderstorms later this evening given the amount of instability and deep layer shear forecast to be around 30kts. Britt .LONG TERM: (Monday through Next Sunday) Issued at 302 PM CDT Sun Jul 6 2014 (Monday and Tuesday) Main concern will be the potential for a few severe thunderstorms on Monday afternoon and night. GFS and NAM both show that upper flow will be west northwesterly on Monday with the front becoming stalled by midday across the central part of the CWA. Temperatures in the lower to middle 90s and dewpoints in the 70s will cause the atmosphere to become very unstable under 7+C/km mid level lapse rates. Scattered thunderstorms may develop along the front as the CINH erodes during the day. Couldn`t rule out that any storms that develop Monday afternoon would be severe because of the amount of the instability. Thunderstorms will be more likely on Monday night when a shortwave trough moves southeast through the upper flow. A complex of thunderstorms will likely move southeast through the area along the front. This complex may be severe given deep layer sheer 40+ kts and produce locally heavy rainfall rates given precipitable waters over 2 inches. Damaging winds appear to be the primary threat...though large hail and isolated tornadoes are also possible. By Tuesday the cold front will still be over the south part of the CWA during the early afternoon hours. There may still be some chance for a few severe thunderstorms along the front as they initiate before the it moves south of the CWA by 00Z. (Wednesday through next Sunday) GFS and ECMWF still show that the cold front will extend from the Mid South back into the central Plains Wednesday and Thursday leaving us dry. 850mb temps are progged to be in the 12-16C range with southeasterly winds from the retreating surface high which will bring us below normal temperatures. The front will begin to move north as a warm front Friday into Saturday which will increase temperatures and thunderstorm chances. The GFS and ECMWF both show a cold front dropping southeastward in northwest flow by next Sunday, so will keep the chance of rain going into the latter half of next weekend. Britt && .AVIATION: (For the 18z TAFs through 18z Monday Afternoon) Issued at 1235 PM CDT Sun Jul 6 2014 Another tricky forecast when it comes to convective trends this forecast period. Activity from this morning has all but diminished across the area, however, a disturbance that will move through the region this afternoon could initiate some diurnal showers/thunderstorms that could impact metro area TAF sites. Given uncertainties in timing and the exact location of any storms that develop, have maintained VCTS mention for KSTL, KSUS, and KCPS this afternoon. A front to the north of the area will sag southward overnight tonight, with showers and thunderstorms expected to impact KUIN by 06Z. Uncertainty remains regarding how far south any nocturnal activity will make it, though models indicate at least some light precipitation across central and eastern Missouri by daybreak. Thus, have mentioned VCSH for KCOU and metro TAF sites in the 09-13Z time frame, though this trend will likely need revisited in future TAF issuances. Otherwise, VFR conditions will prevail outside of any storms, with winds gradually veering more southwesterly through the period. Specifics for KSTL: Currently expect VFR conditions to prevail through the forecast period. There is quite a bit of uncertainty regarding convective trends, with the possibility of diurnal shower/thunderstorm development later this afternoon. Have maintained the VCTS mention from 21-00Z, as the timing and exact location of any storms cannot be pinned down at this time. The other concern is that of precipitation that could impact the terminal after roughly 09Z tonight, associated with a cold front that will slowly sag into northern Missouri overnight. While it appears a bulk of the precipitation would remain north of KSTL, models are indicating at least some light precipitation by daybreak, hence have included VCSH mention from 09-13Z. This will likely need refined in future TAF issuances. Otherwise, southwesterly winds will continue to slowly veer, becoming west-southwesterly by the end of the period. JP && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1235 PM CDT Sun Jul 6 2014 .UPDATE... Issued at 1043 AM CDT SUN JUL 6 2014 Appears HRRR had the best handle on the progress of the MCS remnants up to the present as stratiform showers and scattered convection have descended into southwest Missouri. Warming depicted by IR satellite though would suggest a general decrease in lift across the region associated with a dampening shortwave. Forecast update maintains southward moving precipitation through late morning...becoming more scattered in association with remnant MCV this afternoon. High temperatures have been reduced at least a category across all regions due to cloud cover though do anticipate some recovery in the west as sunshine resumes and south winds pick back up this afternoon. && .SHORT TERM...(Today and Monday) Issued at 310 AM CDT SUN JUL 6 2014 Thunderstorms have developed across north central Missouri to the southwest into southeastern Kansas early this morning. This activity has developed on the nose of a low level jet a ahead of a weak upper level disturbance that is tracking south through the region. This activity will continue to develop and track to the south this morning and will mainly affect locations along an northwest of an Anderson to Bolivar to Vichy Missouri line this morning. This activity will weaken and dissipate by the mid morning hours with the strongest activity generally occurring before sunrise this morning. A few strong storms will be possible early this morning with hail to the size of pennies the main risk mainly before 7 AM this morning then storms should generally weaken as the morning moves a long. A warmer and more humid air mass is spreading north into the region and highs will top out in the upper 80s to the lower 90s this afternoon with heat index values in the middle 90s to near the 100 degree mark. Isolated storms could develop mainly east of Highway 65 this afternoon, but some capping is not expected to completely erode and there will not be much in the way of forcing in place. Therefore, this activity will be very isolated, if it can develop at all, and most locations will remain dry. If storms are able to develop this afternoon, instability will increase in excess of 2000J/kg of ML Cape and this instability and theta-E differences greater than 25K would support a localized downburst wind risk with a few of the storms that can develop. Hot and humid conditions will occur again Monday as highs top out in the lower to middle 90s with heat index values in the upper 90s to around 100 degrees. An unstable air mass will once again be over the area, and with the heating of the day the cap should weaken enough for scattered storms to develop Monday afternoon. Theta-E differences greater than 25K combined with the unstably air mass will once again support a risk for localized damaging straight line winds with a few of the stronger storms Monday afternoon. .LONG TERM...(Monday Night through Saturday) Issued at 310 AM CDT SUN JUL 6 2014 An upper level trough will move out of the northern Plains on Monday night and southeast into the region on Tuesday along with a weak cold front. Storms are expected to develop along the front as it pushes south through the area. There will be a risk for strong to severe storms Tuesday afternoon given a moist and unstable air mass along with an increase in deep layer shear with the approach of the upper level trough. Hail to the size of quarters and winds in excess of 60 mph will be the main risks with this activity. Slightly cooler conditions will occur on Wednesday and Thursday behind the front with highs in the middle to upper 80s. An upper level ridge will begin to build towards the region by late in the week sending the front back to the north. A few storms may develop on Thursday and Friday as the front moves north. Warmer conditions are then expected this weekend as highs warm back into the 90s. && .AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon) Issued at 1230 PM CDT SUN JUL 6 2014 Cluster of SHRA with embedded TSRA already impacting KJLN and KSGF to spread into the KBBG region this afternoon. Current activity to diminish in coverage as shortwave weakens and departs region. Ceilings to clear northwest to southeast during the afternoon...with KBBG clearing this evening. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ UPDATE...Runnels SHORT TERM...RUNNELS LONG TERM...Wise AVIATION...RUNNELS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
324 PM CDT SUN JUL 6 2014 .SYNOPSIS... ISSUED AT 324 PM CDT SUN JUL 6 2014 H5 ANALYSIS FROM EARLIER THIS MORNING HAS HIGH PRESSURE OVER NEVADA WITH A LOW AMPLITUDE RIDGE EXTENDING INTO SWRN CANADA. A SECONDARY HIGH WAS OVER NERN ALASKA WITH A SHARPER AMPLITUDE RIDGE EXTENDING NORTH INTO THE ARCTIC OCEAN. EAST OF THIS RIDGE...A TANDEM OF DECENT NORTHERN STREAM SHORTWAVES WERE PRESENT FROM NORTHERN ALBERTA INTO NORTHERN MANITOBA. DOWNSTREAM OF THESE SHORTWAVES...50+ METER HT FALLS WERE NOTED OVER NRN MN...SWRN ONTARIO AND SOUTHERN MANITOBA. ANOTHER AREA OF SHORTWAVE ENERGY WAS NOTED OVER THE OZARKS. AT THE SURFACE...A WEAK FRONTAL BOUNDARY HAD PASSED THROUGH WESTERN AND NORTH CENTRAL NEBRASKA AS OF NOONTIME AND WAS ORIENTED ALONG A LINE FROM NEAR FORT MORGAN COLORADO...TO MCCOOK TO SIOUX CITY IA. TEMPERATURES AS OF 3 PM CDT...RANGED FROM 86 AT VALENTINE TO 95 AT IMPERIAL. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 324 PM CDT SUN JUL 6 2014 THE PRIMARY CONCERNS THROUGH MONDAY WILL BE PRECIPITATION CHANCES TONIGHT AND MONDAY...THEN WITH HIGH TEMPERATURES ON MONDAY. THE COLD FRONT OVER NEBRASKA HAS PASSED THROUGH ALL OF THE LOCAL AREA AND ALTHOUGH DEWPOINTS JUST NORTH OF THE FRONT REMAIN IN THE 60S...WITH SB CAPE OF 2K J/KG OR HIGHER FROM ABOUT KOGA TO KBBW AND AREAS TO THE SOUTH...LAPS SOUNDINGS AND SPC/S MESOANALYSIS PAGE SUGGEST A SLIGHT CAP REMAINS IN THESE AREAS THIS AFTERNOON. WITH THE CAP AND A LACK OF FORCING TO HELP GET ANY ACTIVITY GOING DON/T EXPECT ANY STORMS LOCALLY THIS EVENING. SOUTH OF THE FRONT CIN HAS DIMINISHED SO COULD SEE STORMS DEVELOP IN THOSE AREAS. DON/T EXPECT THE FRONT TO LIFT NORTH SO HAVE NOT RE-INTRODUCED ANY CHANCES TO THE AREA THIS EVENING ALONG THE FRONT. LATER TONIGHT A FEW MODELS...INCLUDING THE NAM...GFS AND TO A POINT THE RAP SHOW A VERY WEAK PERTURBATION MOVING THROUGH THE MID LEVELS ACROSS CENTRAL NEBRASKA. THE SAME AREA WILL SEE POOLING OF LOW LEVEL MOISTURE WITH DEWPOINTS REMAINING IN THE 60S AND THERE IS SUGGESTION OF A BIT OF MOISTURE TRANSPORT AND CONVERGENCE ROUGHLY IN THE VICINITY OF A LINE FROM KBBW TO KEAR AND KHGI. CONFIDENCE ISN/T HIGH ON ANY OF THIS CONVECTION OCCURRING...NOR HAVING IT OCCUR IN THE FORECAST AREA BUT FELT THERE WAS ENOUGH SIGNALS TO AT LEAST WARRANT A SLIGHT CHANCE FOR THUNDERSTORMS. THEN...THE SHORTWAVE TROUGH CURRENTLY NORTH OF MONTANA WILL MOVE INTO THE NORTHERN PLAINS AND APPROACH NEBRASKA DURING THE DAY MONDAY. THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER WESTERN SOUTH DAKOTA LATE TONIGHT AND MOVE INTO NORTHERN NEBRASKA IN THE MORNING. WITH THE RECOVERY OF DEWPOINTS OVERNIGHT...WILL BE ABLE TO BUILD 1-2K J/KG OF SB CAPE IN THE MORNING AND WITH DEEP LAYER SHEAR INCREASING WITH THE SHORTWAVE MOVING IN CAN/T DISCOUNT A FEW STORMS GAINING STRENGTH TO BE A STRONGER STORM. AT THIS TIME DON/T FORESEE ANY SEVERE STORMS WITHIN THIS ACTIVITY. BY LATE IN THE AFTERNOON THE MOISTURE TRANSPORT ASSOCIATED WITH THE SHORTWAVE SHIFTS AND THEN FOCUSES ACROSS SOUTHERN NEBRASKA AND NORTHERN KANSAS WHERE THE FRONT FROM TODAY WILL REMAIN. THIS FRONT WILL SERVE AS THE FOCUS FOR ADDITIONAL DEVELOPMENT FOR LATE IN THE AFTERNOON AND EVENING. AT THIS POINT...CAPE AND DEEP LAYER SHEAR WILL HAVE INCREASED A BIT SO THE CHANCES FOR SEVERE STORMS WILL ALSO INCREASE. STILL NOT ANTICIPATING WIDESPREAD SEVERE WEATHER LOCALLY AS THE PRIMARY CONVERGENCE AREA LOOKS TO BE SOUTH OF THE FORECAST AREA AS THE MOISTURE TRANSPORT VECTORS ORIENTED SOUTH OVER THE FRONT. OVER THESE AREAS...PRECIPITABLE WATER VALUES ARE HIGH ONCE AGAIN...AT 120 TO 140 PERCENT OF NORMAL. HIGH WATER CONTENT...ALONG WITH A WEST TO EAST ORIENTED FRONT AND MOISTURE TRANSPORT PERPENDICULAR TO THE FRONT COULD SUGGEST POTENTIAL TRAINING STORMS AND HEAVY RAIN. AGAIN...THINK THE HIGHER THREAT THOUGH WILL BE SOUTH OF THE LOCAL FORECAST AREA. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 324 PM CDT SUN JUL 6 2014 MONDAY NIGHT THROUGH WEDNESDAY NIGHT...THE MAIN FORECAST CHALLENGES IN THE MID RANGE ARE LINGERING CHANCES FOR PCPN MONDAY NIGHT AND TEMPERATURES. FOR MONDAY NIGHT...A SLOW MOVING FRONT WILL PUSH INTO KANSAS LATE MONDAY INTO MONDAY NIGHT. THERE WILL CONTINUE TO BE A THREAT FOR PCPN IN THE EAST AND SOUTH MONDAY EVENING...AS DECENT MID LEVEL LIFT WILL PERSIST NORTH OF THE FRONTAL BOUNDARY. THIS AREA IS MORE PREVALENT IN THE FORECAST AREA PER THE GFS SOLN COMPARED TO THE NAM SOLN AS THE SURFACE FRONT IS FURTHER NORTH COMPARED TO THE NAM SOLN. THIS PROBABLY HAS TO DO WITH THE STRENGTH OF HIGH PRESSURE BEHIND THE FRONT...WHICH THE NAM IS STRONGER WITH COMPARED TO THE GFS SOLN. INHERITED FCST HAD CHANCE POPS LINGERING INTO THE OVERNIGHT IN THE SOUTH AND EAST. POPS WERE LOWERED MONDAY NIGHT GIVEN THE FASTER NAM SOLN...AS WELL AS MID LEVEL LIFT SHIFTING SOUTH OF THE FORECAST AREA OVERNIGHT. AS FOR THE THREAT FOR ANY SEVERE STORMS LINGERING INTO THE EVENING HOURS. AT THIS TIME...THE BEST THREAT OF SEVERE STORMS IS EXPECTED TO BE IN THE EAST AND SERN CWA WHERE SFC DEW POINTS WILL BE IN THE 60S. DEEP LAYER SHEAR WILL BE STRONG ACROSS THE ENTIRE CWA...HOWEVER THE COMBINATION OF THE TWO PREVIOUSLY MENTIONED ELEMENTS WILL BE MOST FAVORABLE IN THE EAST AND SERN CWA. HIGH PRESSURE WILL PUSH INTO THE WESTERN DAKOTAS AND NEBRASKA ON TUESDAY. MUCH DRIER AIR WILL PUSH INTO THE AREA AS WELL...ELIMINATING THE THREAT FOR PCPN TUESDAY. BY TUESDAY NIGHT HIGH PRESSURE WILL DRIFT EAST INTO EASTERN NEBRASKA. SOUTHERLY WINDS WILL INCREASE OVERNIGHT...PARTICULARLY IN THE WEST WHICH WILL GIVE A BOOST TO OVERNIGHT LOWS WEST OF NORTH PLATTE. ANY PCPN ACROSS THE HIGH PLAINS...WILL BE CONFINED TO THE FRONT RANGE OF COLORADO AND WILL QUICKLY SUBSIDE DURING THE EVENING HOURS TUESDAY. RIDGING ACROSS THE INTERMOUNTAIN WEST WILL BEGIN TO PUSH EAST ON WEDNESDAY. TEMPERATURES WILL BEGIN TO CLIMB AND WILL APPROACH THE UPPER 80S TO NEAR 90 IN THE WEST WEDNESDAY. THIS IS ABOUT 5 TO 10 DEGREES WARMER THAN FORECAST HIGHS ON TUESDAY. THE THREAT FOR ISOLATED TSRAS WILL INCREASE WEDNESDAY AFTERNOON AND WEDNESDAY NIGHT AS A WEAK UPPER LEVEL DISTURBANCE LIFTS SE FROM THE NRN PERIPHERY OF THE UPPER LEVEL HIGH. BOTH THE NAM AND GFS INITIATE ISOLATED STORMS INVOF THE BLACK HILLS WEDS AFTN. WITH NORTHWESTERLY FLOW ALOFT...ANY STORMS WHICH INITIATE MAY PUSH INTO THE NWRN CWA WEDS AFTN/EVENING. WILL KEEP POPS ISOLATED FOR NOW AS MOISTURE WILL BE FAIRLY LIMITED...ESPECIALLY IN THE WEST AND NWRN CWA. THURSDAY THROUGH SUNDAY...FOR THE END OF THE WEEK INTO NEXT WEEKEND...HIGH PRESSURE WILL BE IN CONTROL OF THE WEATHER PATTERN ACROSS THE SOUTHERN ROCKIES AND SOUTHERN PLAINS. THIS USUALLY ALLOWS A PLETHORA OF MID AND UPPER LEVEL DISTURBANCES TO IMPACT THE CENTRAL AND NORTHERN PLAINS ON THE NORTHERN PERIPHERY OF THIS HIGH PRESSURE. TIMING OF THESE DISTURBANCES IS DIFFICULT TO TIME THIS FAR OUT...SO WILL KEEP POPS LOW IN THE EXTENDED PERIODS. MOISTURE WILL BE AVAILABLE FOR THUNDERSTORM DEVELOPMENT...WITH PLENTY OF MONSOONAL MOISTURE LIFTING NORTH ACROSS THE SOUTHERN AND CENTRAL ROCKIES...SO CANNOT TOTALLY RULE OUT THE THE THREAT FOR STORMS. AS FOR TEMPERATURES LATER IN THE WEEK AND NEXT WEEKEND...UNDERCUT THE LATEST MEX GUIDANCE AS IT CONTINUES TO BE TOO WARM COMPARED TO THE ENSEMBLE MEANS...AS WELL AS THE ECMX EURO GUIDANCE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 110 PM CDT SUN JUL 6 2014 SHOWERS AND STORMS WILL BECOME POSSIBLE LATER TONIGHT OVER NORTH CENTRAL INTO CENTRAL NEBRASKA AS AN UPPER LEVEL SYSTEM MOVES INTO THE PLAINS OUT OF MONTANA. DON/T HAVE HIGH CONFIDENCE ON EXACT AREAS THAT WILL GET MOISTURE AS FORECAST MODELS DON/T HAVE A HIGH LEVEL OF AGREEMENT AT THIS POINT STILL. HOWEVER...WITH THE BETTER MOISTURE AND UPWARD MOTION LOOKING TO MOVE INTO THE AREA IN THE MORNING HOURS DID ADD IN A PREVAILING VCTS AT KVTN WHERE THERE IS A BIT HIGHER CONFIDENCE AND WHERE THE BETTER FORCING IS EXPECTED. WINDS WILL DIMINISH TONIGHT AND BE LIGHT AND VARIABLE BEFORE SWITCHING TO THE NORTHWEST BY LATE MORNING OVER PARTS OF NORTHWEST NEBRASKA. WITH THE EXCEPTION OF THE PASSAGE OF RAINFALL WITH ANY THUNDERSTORMS CONDITIONS WILL BE VFR THROUGH THE NEXT 24 HOURS. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...CLB SHORT TERM...BROOKS LONG TERM...CLB AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
314 PM CDT SUN JUL 6 2014 .SHORT TERM...(TONIGHT THROUGH WEDNESDAY) ISSUED AT 203 PM CDT SUN JUL 6 2014 SURFACE COLD FRONT STRETCHED FROM SOUTHWEST MINNESOTA THROUGH EAST CENTRAL NEBRASKA AND NORTHWEST KANSAS AT 19Z. NOT MUCH IN THE WAY OF CU DEVELOPMENT AHEAD OF THE FRONT SO FAR BUT NOTABLY DRIER AIR BEHIND IT WITH DEWPOINTS IN THE 50S AND 60S. CONVERGENCE RATHER WEAK AS FRONT DRIFTS SLOWLY SOUTH THIS AFTERNOON BEFORE STALLING ALONG THE KANSAS NEBRASKA BORDER THIS EVENING AND WASHING OUT OVERNIGHT. HAVE CARRIED SOME LOW POPS IN THE SOUTH PORTION OF THE AREA FOR TONIGHT WHERE RAP MODEL SHOWS SOME POTENTIAL BUT ONLY ISOLATED COVERAGE EXPECTED IT STORMS DO DEVELOP. A BETTER CHANCE FOR STORMS IN THE AREA MONDAY AFTERNOON AND MONDAY NIGHT AS FAIRLY STRONG MID LEVEL WAVE AND ASSOCIATED JET MAX MOVES ACROSS THE NORTHERN PLAINS AND UPPER MIDWEST HELPING TO PUSH A STRONGER COLD FRONT DOWN ACROSS THE REGION. POTENTIAL FOR HEAVY RAIN EXISTS FOR THE SOUTHERN BORDER AREA MONDAY NIGHT DEPENDING ON ACTUAL LOCATION OF THE FRONT AS STORMS TAKE ON A WEST-EAST ORIENTATION JUST NORTH OF THE BOUNDARY. REMAINDER OF THE PERIOD LOOKS WARM AND DRY FOR TUESDAY AND MOST OF WEDNESDAY WITH LESS HUMIDITY AROUND AS FRONT IS PUSHED FURTHER SOUTH AND HIGH PRESSURE MOVES INTO THE REGION. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 203 PM CDT SUN JUL 6 2014 MOISTURE RETURNS WEDNESDAY NIGHT AS HIGH MOVES TO THE EAST AND SOUTHERLY FLOW INCREASES ACROSS THE REGION. SERIES OF ADDITIONAL SHORT WAVE TROUGHS DURING THE PERIOD INDICATED BY MODELS AS RIDGE BUILDS AGAIN IN THE WEST WILL HAVE POTENTIAL FOR MORE STORMS FOR THE AREA PRIMARILY DURING OVERNIGHT PERIODS AS MID SUMMER PATTERN TAKES SHAPE. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1222 PM CDT SUN JUL 6 2014 VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. SFC CDFNT IS THROUGH THE KOFK TERMINAL AND WILL BE THRU KOMA/KLNK BETWEEN 19-20Z. THIS WILL SWITCH THE WINDS TO N/NW THRU THE OVERNIGHT HOURS. ANY CONVECTIVE THREAT IS TO MINIMAL TO INCLUDE IN THE TAF...AND IF IT OCCURRED WOULD BE MOST LIKELY AT KLNK AFTER 06Z. ANOTHER FRONT WILL MOVE INTO THE AREA ON MON LEADING TO CHCS FOR TSRA BUT THIS APPEARS TO BE AFTER THIS TAF PERIOD. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...FOBERT LONG TERM...FOBERT AVIATION...BOUSTEAD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1225 PM CDT SUN JUL 6 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 311 AM CDT SUN JUL 6 2014 THERE ARE THREE PRIMARY FORECAST CHALLENGES CURRENTLY BEING CONSIDERED: -HEAT INDEX VALUES TODAY -CONVECTION CHANCES THIS AFTERNOON AND EVENING IN THE SOUTH -SEVERE AND HEAVY RAIN POTENTIAL FOR MONDAY AFTERNOON AND NIGHT AT 07Z...SURFACE COLD FRONT WAS ANALYZED FROM NORTH CENTRAL SOUTH DAKOTA INTO FAR NORTHWEST NEBRASKA AND HAD JUST MOVE THROUGH PINE RIDGE. FRONT SHOULD REACH SOUTHEAST NEBRASKA BY LATE AFTERNOON. AIRMASS OVER FORECAST AREA AHEAD OF THE FRONT WILL BE QUITE HUMID WITH DEWPOINTS IN THE LOW TO MID 70S...WITH ONLY SLIGHT COOLING BEHIND THE FRONT. ALOFT...WEAK RIDGING WAS NOTED UPSTREAM WITH MINOR HEIGHT RISES AT 500 MB ACROSS THE DAKOTAS INTO NEBRASKA...WITH FAIRLY WARM MID LEVEL TEMPERATURES. THEREIN LIES THE QUESTION OF THE PAST COUPLE OF DAYS...TRYING TO DETERMINE WHETHER THE FRONT WILL BE ABLE TO TRIGGER CONVECTION TODAY IN A WARM AIRMASS WITH A MODEST CAP AND A LACK OF DEEP VERTICAL MOTION FROM ANY DISTINCT LIFTING MECHANISM OTHER THAN THE FRONT. THE 00Z NAM AND THE 06Z RAP ARE IN GOOD AGREEMENT WITH DEVELOPING CONVECTION ALONG THE FRONT IN THE 22Z-23Z TIME FRAME...AND THE 00Z GFS DEVELOPS IT SLIGHTLY POST FRONTAL BETWEEN 00Z-06Z. NOT SURPRISINGLY...THE NAM AND RAP BOTH ERODE THE CAP FROM ABOUT LINCOLN SOUTH...AND INDICATE VERTICAL MOTION ON THE ORDER OF -4 MICROBARS/SEC THROUGH AROUND 600MB. GIVEN THESE POSSIBLE SCENARIOS...WILL GO WITH A SLIGHT CHANCE IN SOUTHEAST NEBRASKA/SOUTHWEST IOWA FROM 22Z-03Z. REGARDING THE HEAT AND HUMIDITY TODAY...THE COOLING BEHIND THE FRONT IS A CONCERN BUT NEARLY FULL SUN SHOULD KEEP TEMPERATURES FROM DROPPING MUCH. A DEGREE OR TWO DROP IN DEWPOINTS IS EXPECTED IN NORTHERN COUNTIES...BUT NOT IN SOUTHERN COUNTIES UNTIL WELL AFTER THE FRONT PASSES. GENERALLY HAVE NOT MADE CHANGES TO TEMPS TODAY...BUT DID RAISE DEWPOINTS A FEW DEGREES BASED ON READINGS SATURDAY. BOTTOM LINE IS HEAT INDEX VALUES OF 95-100 NORTH AND 100-105 SOUTH. LOOKS LIKE MOST SOUTHERN COUNTIES WILL REMAIN JUST SHY OF HEAT ADVISORY CRITERIA. MODELS IN REASONABLY GOOD AGREEMENT WITH WET PATTERN FOR MONDAY AFTERNOON INTO MONDAY NIGHT. CURRENT FORECAST HAS THIS PERIOD HANDLED WELL. ONLY CHANGES WILL BE TO INCREASE POPS FOR NORTHWEST AREAS MONDAY AFTERNOON...AND ALSO MENTION HEAVY RAIN MONDAY NIGHT ESPECIALLY SOUTH OF I-80 WHERE RECENT RAINS HAVE CAUSED FLOODING IN SOUTHWEST IOWA. HEAVY RAIN OVER THE SOUTHERN COUNTIES LOOKS POSSIBLE GIVEN THE STRONG FRONTAL CONVERGENCE IN THE LOW LEVELS FOR 9-12 HOURS... JET DIVERGENCE AND SHEARED VORTICITY IN NORTHWEST FLOW CAUSING A PROLONGED PERIOD OF LIFT...AND ABUNDANT MOISTURE/INSTABILITY. NAM AND GFS SHOW QUITE STRONG THETA-E ADVECTION FROM 850-700. THIS IS A CONCERN GIVEN THE CURRENT FLOODING IN THE NISHNABOTNA RIVER BASIN IN SOUTHWEST IOWA. WPC DAY 2 EXCESSIVE RAIN GRAPHIC SUPPORTS THIS AS WELL. INGREDIENTS FOR SEVERE CONVECTION MONDAY AFTERNOON AND EVENING APPEAR TO BE LINING UP...PER SPC DAY 2 DISCUSSION. INSTABILITY AND DEEP LAYER SHEAR PARAMETERS MORE THAN SUPPORT A SEVERE WEATHER OUTBREAK WITH UNSEASONABLY FAST UPPER FLOW. BOWING SEGMENTS ALONG THE FRONTAL BOUNDARY IN SOUTHEAST NEBRASKA/SOUTHWEST IOWA SEEM LIKELY. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 311 AM CDT SUN JUL 6 2014 BY LATE TUESDAY THE PRIMARY SYNOPTIC FRONT SHOULD MOVE WELL SOUTH OF THE AREA WITH SURFACE HIGH PRESSURE MOVING INTO THE FORECAST AREA. DRY CONDITIONS ARE EXPECTED TUESDAY NIGHT INTO WEDNESDAY. BY THURSDAY...RETURN FLOW BRINGS MOISTURE BACK INTO THE REGION AND THE UPPER PATTERN MAINTAINS A SOMEWHAT UNSETTLED NORTHWEST FLOW REGIME WITH SOME POTENTIAL FOR MCS ACTIVITY...BUT CONFIDENCE IS LOW THURSDAY INTO SATURDAY. TEMPERATURES SHOULD BE CLOSE TO NORMAL OR A FEW DEGREES BELOW NORMAL. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1222 PM CDT SUN JUL 6 2014 VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. SFC CDFNT IS THROUGH THE KOFK TERMINAL AND WILL BE THRU KOMA/KLNK BETWEEN 19-20Z. THIS WILL SWITCH THE WINDS TO N/NW THRU THE OVERNIGHT HOURS. ANY CONVECTIVE THREAT IS TO MINIMAL TO INCLUDE IN THE TAF...AND IF IT OCCURRED WOULD BE MOST LIKELY AT KLNK AFTER 06Z. ANOTHER FRONT WILL MOVE INTO THE AREA ON MON LEADING TO CHCS FOR TSRA BUT THIS APPEARS TO BE AFTER THIS TAF PERIOD. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...NIETFELD LONG TERM...NIETFELD AVIATION...BOUSTEAD
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
538 PM EDT SUN JUL 6 2014 .SYNOPSIS... AFTER WARM SUNNY CONDITIONS TODAY THE WEATHER WILL BECOME MORE UNSETTLED DURING THE EARLY PART OF THE NEXT WEEK. A SERIES OF WEAK FRONTAL BOUNDARIES WILL PASS ACROSS THE AREA STARTING MONDAY AFTERNOON BRINGING A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY FROM MONDAY INTO WEDNESDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... 530 PM UPDATE... AMPED SKY GRIDS UP TO ACCOUNT FOR THICKER-THAN-EXPECTED WING OF CLOUDS EXTENDING ACROSS THE CENTRAL TWIN TIERS AT THIS TIME. INITIAL NORTHEASTERN PORTION SHOWS UP IN RUC13 RH FIELDS AROUND 500MB. THEN REMAINDER OF THICKER CLOUD SHIELD NOW SPREADING FROM WESTERN TO CENTRAL PA...SHOULD MOVE ACROSS NEPA AND PERHAPS SOME OF THE NY/PA BORDER ZONES LATER THIS EVENING AS PER 700MB RH FIELD OF THE RUC13. VIRGA IS ALSO SHOWING UP ON OUR RADAR CURRENTLY...YET LOW LEVELS ARE MUCH TOO DRY FOR IT TO REACH THE GROUND...AT LEAST INITIALLY. WITH THE WEAK SHORTWAVE INBOUND...THERE HAVE BEEN SOME SCATTERED SPRINKLES INCLUDING BRADFORD PA...THE CITY NOT THE COUNTY. I DO NOT SEE THAT GETTING MUCH PAST THE ALLEGHENY PLATEAU INCLUDING THE WIND FARMS OF BRADFORD PA...THE COUNTY NOT THE CITY...AND PERHAPS NEAR RICKETTS GLEN...AS IT ENCOUNTERS MINOR DOWNSLOPING ANYWHERE BEYOND THAT AS WELL AS CONSIDERABLE LOW LEVEL DRY AIR AND LOSS OF DAYTIME HEATING. MENTION OF SPRINKLES HAS BEEN ADDED TO THE FORECAST THIS EVENING AROUND THOSE AREAS...OTHERWISE LOOKING TOTALLY DRY /AND EVEN FOR THOSE LOCATIONS GETTING A SPRINKLE...OF LITTLE CONSEQUENCE/. PREVIOUS DISCUSSION... A WEAK SHORT WAVE WILL TRACK FROM OHIO ACROSS PENNSYLVANIA THIS EVENING. SOME CLOUDS ASSOCIATED WITH THE WAVE WILL MOVE ACROSS THE AREA... ESPECIALLY NORTHERN PA... BUT THE LOW LEVELS WILL BE TOO DRY FOR ANY PRECIPITATION. PARTLY CLOUDY SKIES WILL CONTINUE OVERNIGHT THEN CLOUDS WILL INCREASE ACROSS THE WEST TOWARD DAYBREAK MONDAY AS THE NEXT WEATHER SYSTEM APPROACHES FROM THE WEST. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... UNSETTLED WEATHER IS EXPECTED FROM MONDAY THROUGH WEDNESDAY AS A PRONOUNCED UPPER LEVEL TROUGH DEVELOPS OVER THE NORTHEAST U.S. AND EASTERN CANADA. A SERIES OF SHORT WAVES WILL SWING EAST ACROSS THE AREA DURING THIS TIME AND LOW-LEVEL MOISTURE WILL INCREASE RAPIDLY... SETTING THE STAGE FOR SHOWERS AND THUNDERSTORMS STARTING MONDAY AFTERNOON. THE FIRST SHORT WAVE TROUGH SWINGS EAST ACROSS THE AREA MONDAY AFTERNOON. THIS UPPER WAVE WILL BE ACCOMPANIED BY A RAPID INCREASE IN LOW-LEVEL MOISTURE WITH MID 60S DEW POINTS BY AFTERNOON. THE AMOUNT OF SUNSHINE MONDAY WILL PLAY A BIG ROLE IN THE INTENSITY AND COVERAGE OF CONVECTION ACROSS OUR AREA DURING THE AFTERNOON AND THERE DOES APPEAR TO BE A GOOD DEAL OF CLOUDINESS CURRENTLY UPSTREAM OVER WISCONSIN... HOWEVER AT THIS POINT WE ARE EXPECTING AT LEAST SOME SUNSHINE WHICH WOULD ALLOW CAPE VALUES TO RISE TO AROUND 1000 J/KG DURING THE AFTERNOON. 0-3 AND 0-6 KM BULK SHEAR VALUES OF 30-35 KTS WILL BE ENOUGH TO SUPPORT THE DEVELOPMENT OF ORGANIZED LINES OF CONVECTION WITH SOME SEVERE POTENTIAL. BASED ON THIS WILL KEEP THE MENTION OF DAMAGING WINDS OR LARGE HAIL IN THE HWO. PWAT VALUES ARE ALSO FORECAST TO INCREASE TO BETWEEN 1.5 AND 2.0 INCHES SO LOCALIZED HEAVY RAIN WILL ALSO BE A CONCERN MONDAY AFTERNOON INTO THE EVENING. COVERAGE SHOULD BE FAIRLY EXTENSIVE AND WE ARE GOING WITH POPS AROUND 70 PERCENT FROM AFTERNOON THROUGH EARLY EVENING. AFTER A LULL MONDAY NIGHT INTO EARLY TUESDAY ANOTHER SHORT WAVE WILL SWING ACROSS THE AREA LATE TUESDAY INTO TUESDAY NIGHT. WITH THE MOIST AIRMASS IN PLACE EXPECT ONCE AGAIN THAT CAPE VALUES WILL CLIMB TO NEAR OR JUST ABOVE 1000 J/KG TUESDAY AFTERNOON WITH THE APPROACHING SHORT WAVE TROUGH AT THE SURFACE AND ALOFT ONCE AGAIN TRIGGERING SHOWERS AND THUNDERSTORMS. DEEP LAYER SHEAR VALUES APPEAR TO BE AT LEAST AS LARGE ON TUESDAY AS MONDAY AND ONCE AGAIN THERE WILL BE SOME SEVERE AND HEAVY RAIN POTENTIAL WITH THESE STORMS INTO TUESDAY EVENING. THE MAIN SURFACE FRONTAL BOUNDARY SHOULD BE EAST OF THE AREA ON WEDNESDAY WITH LOWERING DEW POINTS. THE UPPER TROUGH WILL BE ONLY SLOWLY PROGRESSING EAST ACROSS THE GREAT LAKES AND A FEW SHOWERS MAY YET DEVELOP WEDNESDAY AFTERNOON... BUT POPS WILL BE LOWER THAN MONDAY OR TUESDAY AND THE SEVERE AND HEAVY RAIN POTENTIAL WILL BE LOWER DUE TO LOWER DEW POINTS AND LESS INSTABILITY. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... 230 PM SUN UPDATE... ON THE LARGE-SCALE...WRN CONUS/WRN CANADIAN RIDGING AND A L/WV TROUGH FROM HUDSON`S BAY SWD OVER THE ERN CONUS WILL SET THE PATN THIS PD. HOW AMPLIFIED THIS CONFIGURATION IS...THOUGH WILL VARY OVER TIME. IN GENERAL...THIS TRANSLATES TO AN ABSENCE OF ANY TRULY HOT WX (HIGHS FROM THE 70S-MID 80S)...WITH ROUNDS OF CONVECTION ROLLING THROUGH ABT EVERY 2-3 DAYS. AS FOR THE DAILY SENSIBLE WX...LINGERING SHWRS/TSTMS ARE PSBL AT THE START OF THE PD WED NGT-THU...AS A NRN STREAM S/WV AND SFC COLD FRNT SLOWLY PUSH OFF THE EAST COAST. FRI THROUGH MOST OF SAT LOOK RAIN-FREE AT THIS EARLY VANTAGE PT...WITH THE ERN TROUGH TEMPORARILY RELAXING. FOR THE LATTER PTN OF NEXT WEEKEND...SHWRS AND TSTMS MAY WELL RETURN...AS A RELOADING OF THE L/WV TROUGH AXIS UPSTREAM HERALDS THE APPROACH OF OUR NEXT S/WV...ALG WITH A SFC WARM FRNT. && .AVIATION /22Z SUNDAY THROUGH FRIDAY/... 18Z SUN UPDATE... VFR EXPECTED THROUGH 18Z MON. SOME SHWRS ARE ANTICIPATED MON MRNG...AFTER 12-14Z...BUT THEY SHOULD REMAIN UNRESTRICTED IN NATURE. W TO SW SFC WINDS 5-10 KT THIS AFTN...WILL BECOME SRLY OVERNIGHT...THEN INCREASE AND BECOME GUSTY OUT OF THE SW AFTER 14-15Z MON (GUSTS OF 20-25 KT LIKELY). OUTLOOK... TUE THROUGH THU...ALTHOUGH VFR IS LIKELY THE MAJORITY OF THE TIME...THERE WILL BE SHWRS AND TSTMS IN THE VICINITY...SPCLY DURG THE AFTN AND EVE HRS. BRIEF RESTRICTIONS MAY OCCUR. FRI...VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MDP/MSE NEAR TERM...MDP/MSE SHORT TERM...MSE LONG TERM...MLJ AVIATION...MLJ
AREA FORECAST DISCUSSION
NWS TULSA OK
1240 PM CDT SUN JUL 6 2014 .DISCUSSION... THE 18Z TAF DISCUSSION IS INCLUDED BELOW. && .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. VFR CONDITIONS WILL PREVAIL THIS PERIOD. A WEAK UPPER DISTURBANCE OVER MO WILL MOVE SOUTHEAST ACROSS NW AR...SO THERE IS SOME CHANCE FOR AN AFTERNOON STORM AT THE KXNA AND KFYV TAFS. HAVE INSERTED A VCTS MENTION TO COVER. SOUTH TO SOUTHWEST WINDS WILL BE GUSTY ACROSS NE OK...BUT WILL BACK OFF BY SUNSET THIS EVENING. LACY && .PREV DISCUSSION... /ISSUED 1037 AM CDT SUN JUL 6 2014/ DISCUSSION... LATEST RUNS OF THE HRRR SUGGEST AT LEAST SOME CHANCE OF SHOWERS AND ISOLATED STORMS WILL LINGER INTO THE AFTERNOON OVER NORTHWEST AR IN ASSOCIATION WITH A DISTURBANCE...POSSIBLY EVEN AN MCV...TRACKING SOUTHEAST ACROSS MO ATTM. THE FORECAST HAS BEEN ADJUSTED AND WILL CONTINUE TO MONITOR THE TRENDS. LACY PREV DISCUSSION... /ISSUED 837 AM CDT SUN JUL 6 2014/ DISCUSSION... A LOOSELY ORGANIZED MCS IS TRACKING ACROSS SOUTHWEST MO AND FAR NORTHEAST OK ATTM...IN ASSOCIATION WITH A WAVE (CONVECTIVELY ENHANCED MOST LIKELY) WRAPPING AROUND THE MID LVL RIDGE CENTERED OVER THE CENTRAL ROCKIES. THE SOUTHWEST FLANK IS WEAKENING AS IT TRACKS SOUTHEAST...WITH THE NORTHEAST FLANK REMAINS MORE INTENSE. HAVE THEREFORE INCREASED POPS OVER IN NORTHWEST AR WHERE THE STRONGER ACTIVITY IS HEADED. WILL INCREASE POPS MORE IF NEEDED. LACY PREV DISCUSSION... /ISSUED 631 AM CDT SUN JUL 6 2014/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE ACROSS PARTS OF NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS THIS MORNING. BVO LOOKS TO HAVE THE GREATEST CHANCE OF SEEING PRECIP AND WILL CARRY -RA/VCTS...WHILE KEEPING THE REST OF THE TAF SITES DRY DUE TO LIMITED COVERAGE. OTHERWISE...SCATTERED TO BROKEN MID/HIGH CLOUD DECKS AND BREEZY SOUTHERLY WINDS WILL BE COMMON ACROSS THE REGION TODAY. SOUTHERLY WINDS DECREASE TONIGHT WITH SCATTERED HIGH CLOUDS PERSISTING. VFR CONDITIONS SHOULD CONTINUE THROUGH THE PERIOD. PREV DISCUSSION... /ISSUED 406 AM CDT SUN JUL 6 2014/ DISCUSSION... A FEW SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE ACROSS NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS THIS MORNING AS THE TAIL END OF A SHORTWAVE BRUSHES ACROSS THIS AREA. OTHERWISE THE HEAT WILL BE BUILDING TODAY AND MONDAY AS AN UPPER RIDGE BUILDS OVER THE AREA. SOME MODELS BRING TRIPLE DIGIT HEAT INTO THE WESTERN PART OF THE FORECAST AREA ESPECIALLY MONDAY BUT WILL NOT GO QUITE THAT HOT. A WEAK COLD FRONT WILL MOVE SOUTH INTO THE AREA TUESDAY AFTERNOON AND PROVIDE A FOCUS FOR SCATTERED SHOWERS AND THUNDERSTORMS. THE FRONT WILL STALL WEDNESDAY AND THEN LIFT BACK NORTH AS A WARM FRONT THURSDAY WHICH WILL CONTINUE THE CHANCES FOR SHOWERS AND THUNDERSTORMS. THE UPPER RIDGE BUILDS BACK OVER THE AREA BY NEXT WEEKEND AND BEYOND BRINGING TEMPERATURES AS HOT OR HOTTER THAN WHAT WE WILL SEE THE NEXT COUPLE DAYS. STAYED CLOSE TO GUIDANCE TEMPERATURES THE NEXT COUPLE DAYS. && .PRELIMINARY POINT TEMPS/POPS... TUL 75 97 77 95 / 10 0 10 20 FSM 73 96 74 94 / 0 10 10 10 MLC 74 94 75 94 / 0 0 0 10 BVO 72 97 74 92 / 10 0 10 20 FYV 69 91 70 89 / 0 10 10 30 BYV 69 92 71 88 / 10 10 10 30 MKO 72 95 74 94 / 0 0 0 20 MIO 72 95 74 90 / 10 10 10 30 F10 73 95 74 94 / 0 0 0 10 HHW 72 93 73 92 / 0 10 0 10 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ AVIATION...30
AREA FORECAST DISCUSSION...CORRECTED
NWS AMARILLO TX
553 PM CDT SUN JUL 6 2014 .AVIATION... 00Z TAF CYCLE ISOLATED CONVECTION OVER THE NORTHWEST TEXAS AND THE OKLAHOMA PANHANDLES SHOULD DISSIPATE AFTER SUNSET AROUND 02Z TO 03Z MONDAY. THE CONVECTION IS EXPECTED TO BE CLOSE TO THE GUYMON TAF SITE BUT ONLY VCTS NEEDED AT THIS POINT. THE CONVECTION MAY AFFECT THE DALHART TAF SITE UNTIL AROUND 02Z TO 03Z MONDAY AND THEREFORE WILL INCLUDE A TEMPO GROUP. OTHERWISE...VFR CONDITIONS LIKELY THROUGH 00Z TUESDAY. SOUTH AND SOUTHWEST WINDS 5 TO 15 KNOTS AT ALL THREE TAF SITES THROUGH THE TAF FORECAST PERIOD. SCHNEIDER && .PREV DISCUSSION... /ISSUED 405 PM CDT SUN JUL 6 2014/ UPDATE... ISOLATED CONVECTION DEVELOPING THIS AFTERNOON ACROSS THE NORTH CENTRAL AND NORTHWEST TEXAS PANHANDLE. UPDATED PREVIOUS FORECAST TO EXPAND THE LOW END SLIGHT CHANCE POPS THIS EVENING FURTHER NORTH AND WEST AND CALL FOR AREAL QUALIFIERS RATHER THAN CATEGORICAL PRECIP. ALSO INCREASED SKY COVER MORE THIS EVENING. SCHNEIDER PREV DISCUSSION... /ISSUED 238 PM CDT SUN JUL 6 2014/ DISCUSSION... SURFACE LOW OVER EASTERN COLORADO WITH SURFACE TROUGH EXTENDING BACK ACROSS EASTERN NEW MEXICO AND THE NORTHWEST PORTIONS OF THE FORECAST AREA. UPPER HIGH SITUATED OVER THE CENTRAL ROCKIES AND GREAT BASION REGION MAINTAINING A NORTHERLY TO NORTHEASTERLY UPPER FLOW ACROSS THE PANHANDLES. EMBEDDED SHORTWAVE TROUGH ON THE EASTERN PERIPHERY OF THE UPPER HIGH FORECAST TO DROP SOUTH ACROSS THE TEXAS PANHANDLE AROUND 00Z TO 03Z MONDAY. EXPECT GENERALLY ISOLATED CONVECTION TO DEVELOP ACROSS THE NORTHERN TEXAS PANHANDLE BY MID TO LATE AFTERNOON AND THEN TRACKING SOUTH ACROSS THE REMAINDER OF THE TEXAS PANHANDLE BY 03Z MONDAY. FEEL THAT ANY CONVECTION WILL LIKELY DISSIPATE WITH LOSS OF DAYTIME HEATING AND DECIDED TO INSERT LOW END SLIGHT CHANCE POPS ACROSS PORTIONS OF THE TEXAS PANHANDLE THROUGH 03Z MONDAY. THE LATEST TTU-WRF AND...TO SOME EXTENT...THE HRRR ALONG WITH THE NAM...RUC AND ECMWF SUPPORT THIS SCENARIO. ELONGATED UPPER RIDGE BUILDS IN OVER THE PANHANDLES EARLY THIS WEEK AS A COLD FRONT PUSHES SLOWLY SOUTH INTO THE OKLAHOMA AND NORTHERN TEXAS PANHANDLES LATE MONDAY NIGHT OR EARLY TUESDAY MORNING...06Z TO 12Z TUESDAY. FRONTAL BOUNDARY TO BECOME STATIONARY ACROSS THE TEXAS PANHANDLE TUESDAY WITH LITTLE OR NO UPPER SUPPORT AS THE UPPER RIDGE CONTINUES TO BUILD FROM THE GREAT BASION REGION BACK DOWN INTO THE PANHANDLES AND THE SOUTHERN PLAINS STATES. WEAKNESS ON THE EASTERN PERIPHERY OF THE UPPER RIDGE WILL LEAD TO SHORTWAVE TROUGHS AFFECTING THE FORECAST AREA IN COMBINATION WITH THE STALLED OUT FRONTAL BOUNDARY. WEAK STEERING FLOW WILL RESULT IN CONVECTION...DEVELOPING OVER THE FORECAST AREA...TO MOVE LITTLE AND CAUSING LOCALLY HEAVY RAINFALL AND POSSIBLE FLOODING/FLASH FLOODING CONCERNS BY TUESDAY EVENING THROUGH WEDNESDAY OR WEDNESDAY NIGHT. STALLED FRONTAL BOUNDARY FORECAST TO LIFT NORTHEAST AS A WARM FRONT BY THURSDAY AND FRIDAY AS UPPER RIDGE AND SUBSIDENCE PREVAIL ACROSS THE PANHANDLES. DRY CONDITIONS BY LATE THIS WEEK INTO NEXT WEEKEND. SCHNEIDER FIRE WEATHER... NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED ACROSS THE PANHANDLES THROUGH AT LEAST THE MIDDLE AND END OF NEXT WEEK. SCHNEIDER && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 11/01
AREA FORECAST DISCUSSION
NWS AMARILLO TX
541 PM CDT SUN JUL 6 2014 .AVIATION... 00Z TAF CYCLE ISOLATED CONVECTION OVER THE NORTHWEST TEXAS AND THE OKLAHOMA PANHANDLES SHOULD DISSIPATE AFTER SUNSET AROUND 02Z TO 03Z MONDAY. THE CONVECTION IS EXPECTED TO BE CLOSE TO THE GUYMON TAF SITE BUT ONLY VCTS NEEDED AT THIS POINT. THE CONVECTION MAY AFFECT THE DALHART TAF SITE UNTIL AROUND 02Z TO 03Z MONDAY AND THEREFORE WILL INCLUDE A PROB30 GROUP. OTHERWISE...VFR CONDITIONS LIKELY THROUGH 00Z TUESDAY. SOUTH AND SOUTHWEST WINDS 5 TO 15 KNOTS AT ALL THREE TAF SITES THROUGH THE TAF FORECAST PERIOD. SCHNEIDER && .PREV DISCUSSION... /ISSUED 405 PM CDT SUN JUL 6 2014/ UPDATE... ISOLATED CONVECTION DEVELOPING THIS AFTERNOON ACROSS THE NORTH CENTRAL AND NORTHWEST TEXAS PANHANDLE. UPDATED PREVIOUS FORECAST TO EXPAND THE LOW END SLIGHT CHANCE POPS THIS EVENING FURTHER NORTH AND WEST AND CALL FOR AREAL QUALIFIERS RATHER THAN CATEGORICAL PRECIP. ALSO INCREASED SKY COVER MORE THIS EVENING. SCHNEIDER PREV DISCUSSION... /ISSUED 238 PM CDT SUN JUL 6 2014/ DISCUSSION... SURFACE LOW OVER EASTERN COLORADO WITH SURFACE TROUGH EXTENDING BACK ACROSS EASTERN NEW MEXICO AND THE NORTHWEST PORTIONS OF THE FORECAST AREA. UPPER HIGH SITUATED OVER THE CENTRAL ROCKIES AND GREAT BASION REGION MAINTAINING A NORTHERLY TO NORTHEASTERLY UPPER FLOW ACROSS THE PANHANDLES. EMBEDDED SHORTWAVE TROUGH ON THE EASTERN PERIPHERY OF THE UPPER HIGH FORECAST TO DROP SOUTH ACROSS THE TEXAS PANHANDLE AROUND 00Z TO 03Z MONDAY. EXPECT GENERALLY ISOLATED CONVECTION TO DEVELOP ACROSS THE NORTHERN TEXAS PANHANDLE BY MID TO LATE AFTERNOON AND THEN TRACKING SOUTH ACROSS THE REMAINDER OF THE TEXAS PANHANDLE BY 03Z MONDAY. FEEL THAT ANY CONVECTION WILL LIKELY DISSIPATE WITH LOSS OF DAYTIME HEATING AND DECIDED TO INSERT LOW END SLIGHT CHANCE POPS ACROSS PORTIONS OF THE TEXAS PANHANDLE THROUGH 03Z MONDAY. THE LATEST TTU-WRF AND...TO SOME EXTENT...THE HRRR ALONG WITH THE NAM...RUC AND ECMWF SUPPORT THIS SCENARIO. ELONGATED UPPER RIDGE BUILDS IN OVER THE PANHANDLES EARLY THIS WEEK AS A COLD FRONT PUSHES SLOWLY SOUTH INTO THE OKLAHOMA AND NORTHERN TEXAS PANHANDLES LATE MONDAY NIGHT OR EARLY TUESDAY MORNING...06Z TO 12Z TUESDAY. FRONTAL BOUNDARY TO BECOME STATIONARY ACROSS THE TEXAS PANHANDLE TUESDAY WITH LITTLE OR NO UPPER SUPPORT AS THE UPPER RIDGE CONTINUES TO BUILD FROM THE GREAT BASION REGION BACK DOWN INTO THE PANHANDLES AND THE SOUTHERN PLAINS STATES. WEAKNESS ON THE EASTERN PERIPHERY OF THE UPPER RIDGE WILL LEAD TO SHORTWAVE TROUGHS AFFECTING THE FORECAST AREA IN COMBINATION WITH THE STALLED OUT FRONTAL BOUNDARY. WEAK STEERING FLOW WILL RESULT IN CONVECTION...DEVELOPING OVER THE FORECAST AREA...TO MOVE LITTLE AND CAUSING LOCALLY HEAVY RAINFALL AND POSSIBLE FLOODING/FLASH FLOODING CONCERNS BY TUESDAY EVENING THROUGH WEDNESDAY OR WEDNESDAY NIGHT. STALLED FRONTAL BOUNDARY FORECAST TO LIFT NORTHEAST AS A WARM FRONT BY THURSDAY AND FRIDAY AS UPPER RIDGE AND SUBSIDENCE PREVAIL ACROSS THE PANHANDLES. DRY CONDITIONS BY LATE THIS WEEK INTO NEXT WEEKEND. SCHNEIDER FIRE WEATHER... NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED ACROSS THE PANHANDLES THROUGH AT LEAST THE MIDDLE AND END OF NEXT WEEK. SCHNEIDER && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 11/01
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
405 PM CDT SUN JUL 6 2014 .UPDATE... ISOLATED CONVECTION DEVELOPING THIS AFTERNOON ACROSS THE NORTH CENTRAL AND NORTHWEST TEXAS PANHANDLE. UPDATED PREVIOUS FORECAST TO EXPAND THE LOW END SLIGHT CHANCE POPS THIS EVENING FURTHER NORTH AND WEST AND CALL FOR AREAL QUALIFIERS RATHER THAN CATEGORICAL PRECIP. ALSO INCREASED SKY COVER MORE THIS EVENING. SCHNEIDER && .PREV DISCUSSION... /ISSUED 238 PM CDT SUN JUL 6 2014/ DISCUSSION... SURFACE LOW OVER EASTERN COLORADO WITH SURFACE TROUGH EXTENDING BACK ACROSS EASTERN NEW MEXICO AND THE NORTHWEST PORTIONS OF THE FORECAST AREA. UPPER HIGH SITUATED OVER THE CENTRAL ROCKIES AND GREAT BASION REGION MAINTAINING A NORTHERLY TO NORTHEASTERLY UPPER FLOW ACROSS THE PANHANDLES. EMBEDDED SHORTWAVE TROUGH ON THE EASTERN PERIPHERY OF THE UPPER HIGH FORECAST TO DROP SOUTH ACROSS THE TEXAS PANHANDLE AROUND 00Z TO 03Z MONDAY. EXPECT GENERALLY ISOLATED CONVECTION TO DEVELOP ACROSS THE NORTHERN TEXAS PANHANDLE BY MID TO LATE AFTERNOON AND THEN TRACKING SOUTH ACROSS THE REMAINDER OF THE TEXAS PANHANDLE BY 03Z MONDAY. FEEL THAT ANY CONVECTION WILL LIKELY DISSIPATE WITH LOSS OF DAYTIME HEATING AND DECIDED TO INSERT LOW END SLIGHT CHANCE POPS ACROSS PORTIONS OF THE TEXAS PANHANDLE THROUGH 03Z MONDAY. THE LATEST TTU-WRF AND...TO SOME EXTENT...THE HRRR ALONG WITH THE NAM...RUC AND ECMWF SUPPORT THIS SCENARIO. ELONGATED UPPER RIDGE BUILDS IN OVER THE PANHANDLES EARLY THIS WEEK AS A COLD FRONT PUSHES SLOWLY SOUTH INTO THE OKLAHOMA AND NORTHERN TEXAS PANHANDLES LATE MONDAY NIGHT OR EARLY TUESDAY MORNING...06Z TO 12Z TUESDAY. FRONTAL BOUNDARY TO BECOME STATIONARY ACROSS THE TEXAS PANHANDLE TUESDAY WITH LITTLE OR NO UPPER SUPPORT AS THE UPPER RIDGE CONTINUES TO BUILD FROM THE GREAT BASION REGION BACK DOWN INTO THE PANHANDLES AND THE SOUTHERN PLAINS STATES. WEAKNESS ON THE EASTERN PERIPHERY OF THE UPPER RIDGE WILL LEAD TO SHORTWAVE TROUGHS AFFECTING THE FORECAST AREA IN COMBINATION WITH THE STALLED OUT FRONTAL BOUNDARY. WEAK STEERING FLOW WILL RESULT IN CONVECTION...DEVELOPING OVER THE FORECAST AREA...TO MOVE LITTLE AND CAUSING LOCALLY HEAVY RAINFALL AND POSSIBLE FLOODING/FLASH FLOODING CONCERNS BY TUESDAY EVENING THROUGH WEDNESDAY OR WEDNESDAY NIGHT. STALLED FRONTAL BOUNDARY FORECAST TO LIFT NORTHEAST AS A WARM FRONT BY THURSDAY AND FRIDAY AS UPPER RIDGE AND SUBSIDENCE PREVAIL ACROSS THE PANHANDLES. DRY CONDITIONS BY LATE THIS WEEK INTO NEXT WEEKEND. SCHNEIDER FIRE WEATHER... NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED ACROSS THE PANHANDLES THROUGH AT LEAST THE MIDDLE AND END OF NEXT WEEK. SCHNEIDER && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 19/11
AREA FORECAST DISCUSSION
NWS AMARILLO TX
238 PM CDT SUN JUL 6 2014 .DISCUSSION... SURFACE LOW OVER EASTERN COLORADO WITH SURFACE TROUGH EXTENDING BACK ACROSS EASTERN NEW MEXICO AND THE NORTHWEST PORTIONS OF THE FORECAST AREA. UPPER HIGH SITUATED OVER THE CENTRAL ROCKIES AND GREAT BASION REGION MAINTAINING A NORTHERLY TO NORTHEASTERLY UPPER FLOW ACROSS THE PANHANDLES. EMBEDDED SHORTWAVE TROUGH ON THE EASTERN PERIPHERY OF THE UPPER HIGH FORECAST TO DROP SOUTH ACROSS THE TEXAS PANHANDLE AROUND 00Z TO 03Z MONDAY. EXPECT GENERALLY ISOLATED CONVECTION TO DEVELOP ACROSS THE NORTHERN TEXAS PANHANDLE BY MID TO LATE AFTERNOON AND THEN TRACKING SOUTH ACROSS THE REMAINDER OF THE TEXAS PANHANDLE BY 03Z MONDAY. FEEL THAT ANY CONVECTION WILL LIKELY DISSIPATE WITH LOSS OF DAYTIME HEATING AND DECIDED TO INSERT LOW END SLIGHT CHANCE POPS ACROSS PORTIONS OF THE TEXAS PANHANDLE THROUGH 03Z MONDAY. THE LATEST TTU-WRF AND...TO SOME EXTENT...THE HRRR ALONG WITH THE NAM...RUC AND ECMWF SUPPORT THIS SCENARIO. ELONGATED UPPER RIDGE BUILDS IN OVER THE PANHANDLES EARLY THIS WEEK AS A COLD FRONT PUSHES SLOWLY SOUTH INTO THE OKLAHOMA AND NORTHERN TEXAS PANHANDLES LATE MONDAY NIGHT OR EARLY TUESDAY MORNING...06Z TO 12Z TUESDAY. FRONTAL BOUNDARY TO BECOME STATIONARY ACROSS THE TEXAS PANHANDLE TUESDAY WITH LITTLE OR NO UPPER SUPPORT AS THE UPPER RIDGE CONTINUES TO BUILD FROM THE GREAT BASION REGION BACK DOWN INTO THE PANHANDLES AND THE SOUTHERN PLAINS STATES. WEAKNESS ON THE EASTERN PERIPHERY OF THE UPPER RIDGE WILL LEAD TO SHORTWAVE TROUGHS AFFECTING THE FORECAST AREA IN COMBINATION WITH THE STALLED OUT FRONTAL BOUNDARY. WEAK STEERING FLOW WILL RESULT IN CONVECTION...DEVELOPING OVER THE FORECAST AREA...TO MOVE LITTLE AND CAUSING LOCALLY HEAVY RAINFALL AND POSSIBLE FLOODING/FLASH FLOODING CONCERNS BY TUESDAY EVENING THROUGH WEDNESDAY OR WEDNESDAY NIGHT. STALLED FRONTAL BOUNDARY FORECAST TO LIFT NORTHEAST AS A WARM FRONT BY THURSDAY AND FRIDAY AS UPPER RIDGE AND SUBSIDENCE PREVAIL ACROSS THE PANHANDLES. DRY CONDITIONS BY LATE THIS WEEK INTO NEXT WEEKEND. SCHNEIDER && .FIRE WEATHER... NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED ACROSS THE PANHANDLES THROUGH AT LEAST THE MIDDLE AND END OF NEXT WEEK. SCHNEIDER && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 67 95 67 91 69 / 20 5 5 20 40 BEAVER OK 72 103 72 92 68 / 5 5 5 20 30 BOISE CITY OK 66 100 70 89 65 / 10 5 5 30 30 BORGER TX 68 101 69 94 71 / 20 5 5 20 40 BOYS RANCH TX 67 100 68 95 71 / 20 5 5 20 40 CANYON TX 66 95 65 92 68 / 20 5 5 10 40 CLARENDON TX 69 96 69 94 70 / 20 5 5 10 30 DALHART TX 67 99 67 91 66 / 20 5 5 30 40 GUYMON OK 70 102 70 91 68 / 5 5 5 30 40 HEREFORD TX 64 94 63 92 67 / 20 5 5 10 30 LIPSCOMB TX 71 100 72 92 67 / 20 5 5 20 30 PAMPA TX 69 97 70 92 69 / 20 5 5 20 40 SHAMROCK TX 70 97 70 94 68 / 20 5 5 10 30 WELLINGTON TX 72 99 71 97 70 / 20 5 5 5 30 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 13/11
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1228 PM CDT SUN JUL 6 2014 .AVIATION... HAVE AFTERNOON VCSH/VCTS IN THE 18Z TAFS AS DAYTIME HEATING HELPS TO INITIATE MORE SHRA/TSRA. EXPECT WEAKENING AND DISSIPATION THIS EVENING...THEN POSSIBLE MVFR FOG DEVELOPMENT OVERNIGHT WHERE GROUNDS ARE WET. FOR TOMORROW...CARRIED VCSH NEAR THE COAST AROUND SUNRISE AND THEN A LITTLE FURTHER INLAND DURING THE MORNING HOURS. EXPECT TO SEE MORE SHRA/TSRA DEVELOPMENT ON MONDAY. 42 && .PREV DISCUSSION... /ISSUED 919 AM CDT SUN JUL 6 2014/ UPDATE... SEE DISCUSSION FOR MORNING UPDATE. DISCUSSION... NOT MUCH CHANGE IN PATTERN FROM YESTERDAY. SCATTERED SHOWERS AND THUNDERSTORMS HAVE FORMED OVER THE WATERS THIS MORNING AND HAVE STARTED TO MOVE INLAND. GFS AND NAM FORECAST SOUNDINGS SHOWING PWATS AROUND 1.7" THIS AFTERNOON WITH K INDICES IN THE LOWER TO MID 30S. EXPECTING COVERAGE TO INCREASE OVER INLAND AREAS THIS AFTERNOON THANKS TO DAY TIME HEATING. HIGH RES HRRR AND TEXAS TECH WRF AGAIN SHOWING GREATEST CHANCES TOWARDS THE SOUTHWEST. GRANTED THEY HAVE NOT INITIALIZED GREAT. COVERAGE MIGHT AGAIN BE MORE THAN 40 PERCENT IN SOME AREAS BUT GIVEN MESOSCALE NATURE OF STORMS HARD TO PIN POINT EXACT LOCATION. CURRENT FORECAST HAS TAKEN THE ABOVE INTO ACCOUNT. NO UPDATE REQUIRED AT THIS TIME. 23 PREV DISCUSSION... /ISSUED 355 AM CDT SUN JUL 6 2014/ DISCUSSION... CURRENT FCST LOOKS GOOD AND MADE VERY FEW CHANGES TO IT. EXPECT GENERAL PATTERN OF ISO/SCT PRECIP TO DEVELOP OFFSHORE LATE NIGHT & EARLY MORNING THEN TRANSITION INLAND DURING THE DAY COMPLIMENTS OF DAYTIME HEATING AND THE SEABREEZE. OVERALL COVERAGE DEPENDS ON SLIGHT VARIATIONS OF MOISTURE AVAILABILITY & LOCATION EACH DAY. SFC HIGH PRES SHOULD REMAIN CENTERED OFF TO THE EAST ALLOWING WEAK ONSHORE FLOW TO PERSIST. FURTHER ALOFT...LOOKS LIKE WE`LL REMAIN IN A SLIGHT WEAKNESS BETWEEN RIDGES. SOME OF THE MEDIUM RANGE SOLNS DO SUGGEST UPPER RIDGE BUILDING FURTHER OVERHEAD TOWARD NEXT WEEKEND WHICH WOULD BRING RAIN CHANCES DOWN AND TEMPS UP. JUST SOMETHING TO KEEP AN EYE ON - BUT PERSISTENCE FCST WILL DO FOR NOW. 47 MARINE... AS HIGH PRESSURE EDGES OFF TO THE EAST THE ONSHORE FLOW SHOULD BE IN- CREASING SLIGHTLY THE NEXT DAY OR SO. THESE LIGHT/MODERATE WINDS ARE FCST TO PERSIST FOR MUCH OF THE WEEK AS THE WX PATTERN REMAINS GENER- ALLY QUIET. NO ADVISORIES/CAUTION FLAGS ARE ANTICIPATED EXPECTED THE NEXT SEVERAL DAYS. 41 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 93 73 93 74 93 / 20 20 30 10 20 HOUSTON (IAH) 92 74 92 75 92 / 30 20 30 10 30 GALVESTON (GLS) 89 79 89 80 90 / 30 20 20 20 20 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...23 AVIATION/MARINE...42
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
550 PM CDT SUN JUL 6 2014 .MESOSCALE DISCUSSION... ISSUED AT 331 PM CDT SUN JUL 6 2014 NUMEROUS SHOWERS AND THUNDERSTORMS CONTINUE TO DEVELOP ALONG AND NORTH OF INTERSTATE 90...ESPECIALLY IN WISCONSIN. THESE ARE ON THE NOSE OF 850MB MOISTURE TRANSPORT AND BASICALLY THE FINE LINE BACK EDGE IS THE 850MB FRONT DEPICTED IN RAP ANALYSIS. THE STRONGEST CORE HAS BEEN OVER TREMPEALEAU COUNTY...AND DOES HAVE SOME MID- LEVEL ROTATION...HOWEVER MUCH OF THE CORE APPEARS TO BE RAIN. NOT ANTICIPATING ANY OF THIS ELEVATED DRIVEN CONVECTION TO TURN SEVERE. FARTHER TO THE WEST...STILL MONITORING FOR SHOWERS AND THUNDERSTORMS TO DEVELOP FROM NORTH CENTRAL IOWA TO SOUTH CENTRAL MN AND WEST CENTRAL WI. SEEING A TOWERING CUMULUS LINE ON VISIBLE IMAGERY...BUT OVERALL DEEP- MOISTURE AND EVEN SURFACE CONVERGENCE ALONG THIS TROUGH IS WEAK. LOOKING AT THE SURFACE FLOW...IT GOES SOUTHWEST AT RST TO NEARLY WEST AT I-35 TO NORTHWEST AT NEW ULM...A LONG DISTANCE. RAP ANALYSIS DOES SHOW 2500-3500 J/KG OF MLCAPE WITH LITTLE CIN IN THIS CORRIDOR...THOUGH. THUS...A WAIT AND SEE IF ANYTHING CAN POP. SHOULD A STORM FIRE...IT WILL PROBABLY TURN SEVERE QUICKLY. NEEDLESS TO SAY...THE COMBINATION OF THE LONG PERIOD OF HAVING THE STRATUS AROUND TODAY AND NOT A LOT OF CONVERGENCE ON THE FRONT HAVE BEEN DETRIMENTAL TO SEVERE POTENTIAL. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 201 PM CDT SUN JUL 6 2014 MAIN SHORT TERM CONCERNS ARE ON CONVECTIVE EVOLUTION AND SEVERE POTENTIAL FOR THIS AFTERNOON/EVENING AND AGAIN LATE MONDAY. CURRENTLY AS OF 19Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED STRONG RIDGING OVER THE WESTERN U.S. WHILE GENERAL WEAK TROUGHING PRESIDED OVER THE GREAT LAKES. A WEAK SHORTWAVE WAS EVIDENT OVER CENTRAL MN. ACCOMPANYING THIS SHORTWAVE PER THE RAP AT 800MB WERE 30 KT NORTHWEST WINDS AND 14-15C TEMPERATURES. COMPARE THIS TO 25-30 KT SOUTHWEST WINDS AND 18-20C TEMPERATURES OVER THE FORECAST AREA. THAT WARM NOSE COMBINED WITH MORNING STRATUS AND DEBRIS CLOUDS HAS KEPT CONDITIONS CAPPED THUS FAR. EDGE OF CAP REFLECTED NICELY TOO BY SOME ELEVATED SHOWERS AND THUNDERSTORMS GOING ON OVER WEST-CENTRAL WISCONSIN. TEMPERATURES FOR THE MOST PART HAVE BEEN STUCK IN THE 70S WITH A FEW 80S WHERE CLEARING BRIEFLY OCCURRED IN SOUTHEAST MN AND WEST CENTRAL WI. DEWPOINTS HAVE BEEN ON THE RISE...THOUGH...NOW IN THE LOW 70S. BACK IN WESTERN IA... EVAPOTRANSPORATION PUSHING DEWPOINTS THERE IN THE UPPER 70S. THINKING THESE HIGHER DEWPOINTS ADVECTING TOWARDS THE AREA IS NOT HELPING MATTERS TO CLEAR THE STRATUS. THE AFOREMENTIONED TEMPERATURES AND DEWPOINTS HAVE RESULTED IN MLCAPE VALUES OF 1500- 2010 J/KG WHILE MLCIN SITS 50-100 J/KG WHERE IT CLEARED TO 201-300 J/KG WHERE ITS STILL CLOUDY. MEANWHILE...IN SOUTHWEST MN... DEWPOINTS HAVE FALLEN OFF INTO MID LOW 50S BEHIND A TROUGH/DRYLINE THAT STRETCHES FROM NORTHWEST IOWA INTO NORTHWEST WI. ANTICIPATING CONVECTION TO FIRE IN THE NEXT 1-2 HOURS ALONG THE TROUGH/DRYLINE NEAR/WEST OF THE FORECAST AREA AS DAYTIME HEATING CONTINUES TO GET RID OF THE CIN. CONVECTION SHOULD TAKE ON A SCATTERED NATURE GIVEN THE CAP IN PLACE. WHERE CONVECTION DOES FIRE...0-3KM AND 0-6KM SHEAR ARE ON THE ORDER OF 20-25KT... WHICH SHOULD FAVOR MORE MULTI-CELLULAR ACTIVITY. GIVEN THE AMOUNT OF CAPE...CANNOT RULE OUT AN INITIAL SUPERCELL...BUT THINKING MORE INTENSE MULTI-CELLS ARE MORE LIKELY. LARGE HAIL AND DAMAGING WINDS WILL BE THE MAIN CONCERNS. GENERAL MODEL CONSENSUS OF BOTH DETERMINISTIC AND HIGH RESOLUTION MODELS SUGGEST MUCH OF THE CONVECTION SHOULD BE SOUTHEAST OF THE FORECAST AREA BY 01-02Z. HOWEVER...THERE IS POTENTIAL THAT THE CONVECTION DOESNT EVEN MAKE IT INTO THE SOUTHEAST END OF THE FORECAST AREA BECAUSE OF THE MASSIVE AMOUNT OF CIN RIGHT NOW IN PLACE. MANY HRRR RUNS TODAY HAVE SHOWN THIS. MUCH OF TONIGHT AND INTO MONDAY MORNING THEN LOOKS DRY AS UNIDIRECTIONAL NORTHWEST FLOW FROM THE SURFACE TO 500MB BRINGS IN SOMEWHAT COOLER AND DRIER AIR IN FROM NORTH DAKOTA. THIS IS REFLECTED WELL IN GOES PRECIPITABLE WATER IMAGERY WHICH SHOWS VALUES OF 1 INCH OR LESS OVER WESTERN MN COMPARED TO 1.5-1.75 INCHES OVER THE FORECAST AREA. HEADING INTO MONDAY AFTERNOON...A LONG WAVE SHORTWAVE TROUGH IS PROGGED TO DROP INTO THE EASTERN DAKOTAS AND WESTERN MN. INCREASING 850MB MOISTURE TRANSPORT AHEAD OF THE TROUGH...COMBINED WITH 1000- 1500 J/KG OF MLCAPE WITH LITTLE CAPPING AND A SURFACE TROUGH MOVING THROUGH...SHOULD RESULT IN A DECENT AMOUNT OF CONVECTION ACROSS MINNESOTA IN THE AFTERNOON HOURS...AS DEPICTED TOO BY DETERMINISTIC AND HIGH RESOLUTION GUIDANCE. THIS CONVECTION COULD SPREAD INTO THE NORTHWEST HALF OF THE FORECAST AREA BY LATE IN THE DAY. GIVEN 0-3KM SHEAR VALUES OF 25-35 KT AND MORE IMPORTANTLY 0-6KM SHEAR VALUES OF 40-55 KT...ORGANIZED SEVERE CONVECTION STILL APPEARS POSSIBLE. COULD END UP SEEING A MIX OF SUPERCELL AND LINE SEGMENTS...THOUGH THE SHEAR BEING UNIDIRECTIONAL MAY FAVOR MORE LINE SEGMENTS AND THUS DAMAGING WINDS. NEED TO WATCH THE LARGE HAIL CONCERN INITIALLY TOO GIVEN LOWER FREEZING LEVELS...DROPPING FROM NEAR 14000 FT THIS AFTERNOON TO 12010 FT LATE MONDAY. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 201 PM CDT SUN JUL 6 2014 MAIN HIGHLIGHTS FOR THE LONG TERM PERIOD ARE SEVERE POTENTIAL MONDAY EVENING FOLLOWED BY COOLER WEATHER FOR MID-WEEK. MONDAY NIGHT...BOTH THE LONG WAVE SHORTWAVE TROUGH AT 500MB AND THE ASSOCIATED SURFACE TROUGH ARE PROGGED TO MOVE SOUTHEAST THROUGH THE REGION. THERE ALSO APPEARS TO BE A POINT IN THE EVENING WHERE WE GET INTO A LEFT EXIT REGION OF AN UPPER JET STREAK. COMBINE THIS DYNAMICAL FORCING WITH AN 850MB MOISTURE TRANSPORT PLUME AND LINGERING INSTABILITY MEANS WE SHOULD BE ABLE TO KEEP SOME SHOWERS AND THUNDERSTORMS GOING THROUGH THE EVENING. UNTIL INSTABILITY WANES...EXPECT A SEVERE THREAT TO EXIST...JUST AS THE 06.12Z HIRES ARW/NMM SUGGEST. MUCH OF THE CONVECTION COULD BE EAST OF THE AREA BY THE OVERNIGHT HOURS...OR AT LEAST OVER THE SOUTHEAST HALF...SO PRECIPITATION DIMINISH NORTHWEST TO SOUTHEAST THROUGH THE NIGHT. PLUS...PRECIPITABLE WATER VALUES TANK AGAIN AFTER BRIEFLY COMING UP MONDAY AFTERNOON. ON TUESDAY...MODEL AGREEMENT IS GOOD ON SETTING UP AN UPPER LEVEL TROUGH FROM NORTHERN ONTARIO SOUTHWARD THROUGH THE WESTERN GREAT LAKES REGION. COOL AIR ALOFT COMBINED WITH A SHORTWAVE DROPPING THROUGH THIS TROUGH IN WISCONSIN...DAYTIME HEATING...AS WELL AS LINGERING LOW LEVEL MOISTURE COULD SPARK SOME DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS. BEST CHANCE FOR THIS WILL BE IN WISCONSIN WITH THE SHORTWAVE DROPPING THROUGH. DRIER WEATHER LOOKS TO PREVAIL TUESDAY NIGHT THROUGH THURSDAY WITH THE FORECAST AREA. THIS IS A RESULT OF A DRIER WESTERN CANADIAN HIGH PRESSURE AREA MOVING THROUGH...AND BEING AROUND THE INFLECTION POINT BEHIND THE WESTERN GREAT LAKES UPPER TROUGH PUSHING OFF TO THE EAST. TEMPERATURES ARE LIKELY TO BE A BIT ON THE COOL SIDE WITH 850MB TEMP ANOMALIES ABOUT 1 STANDARD DEVIATION BELOW NORMAL...OR BETWEEN 9- 13C. LOW PRECIPITABLE WATER AROUND 0.75 INCHES WILL HELP TOO IN RADIATIVE COOLING AT NIGHT...ALONG WITH MIXING OF DEWPOINTS IN THE DAY. COULD SEE SOME VALLEY FOG TUESDAY AND WEDNESDAY NIGHTS. FOR THURSDAY NIGHT INTO THE WEEKEND. WARM ADVECTION BEGINS IN EARNEST THURSDAY NIGHT AS THE HIGH HEADS OFF TO THE EAST. MODEL CONSENSUS IS FOR NUMEROUS SHOWERS AND THUNDERSTORMS TO INITIATE WITH THE MOISTURE RETURN FROM THE UPPER MIDWEST SOUTHWARD INTO THE CENTRAL PLAINS...PERHAPS CREEPING INTO THE FORECAST AREA EITHER LATE THURSDAY NIGHT OR DURING THE DAY FRIDAY. STORM CHANCES THEN LOOK TO CONTINUE THROUGH SATURDAY AS AN UPPER TROUGH DROPS SOUTH FROM MANITOBA INTO THE WESTERN GREAT LAKES REGION. PERHAPS BY SUNDAY ALL THE CONVECTIVE POTENTIAL WILL GET SHOVED TO THE SOUTH AS THE UPPER TROUGH CONTINUES TO DIG SOUTHEASTWARD. HOWEVER...HAVE STILL MAINTAINED CHANCES OF SHOWERS AND THUNDERSTORMS ACROSS SOUTHERN PORTIONS OF THE FORECAST AREA. TEMPERATURE WISE...850MB TEMPS GENERALLY RANGE 16-18C THROUGH SATURDAY...SUPPORTING HIGHS IN THE 80S. THESE SHOULD COOL BACK SOME ON SUNDAY WITH THE TROUGH DROPPING IN. HUMIDITY WILL BE UP TOO FRIDAY AND SATURDAY WITH THAT RETURN FLOW...EVAPOTRANSPORATION AND POTENTIAL CONVECTION ADDING MOISTURE TO THE BOUNDARY LAYER. && .AVIATION...(FOR THE 00Z TAFS...THROUGH 00Z MONDAY EVENING) ISSUED AT 550 PM CDT SUN JUL 6 2014 SHRA/TS HAVE FIRED ALONG AND AHEAD OF A FRONT/DRY LINE TRACKING EAST ACROSS EASTERN MN/IA EARLY THIS EVENING...AND SHOULD BE EAST OF KRST BY 00Z...BUT COULD LINGER FOR AN HOUR OR TWO NEAR KLSE PAST TAF ISSUANCE. SKIES WILL CLEAR BY MID EVENING...WITH VFR CONDITIONS THEN EXPECTED THROUGH MONDAY MORNING. ANOTHER UPPER LEVEL TROUGH/SFC FRONT COMBO WILL SLIDE ACROSS THE UPPER MISSISSIPPI RIVER VALLEY MONDAY AFTERNOON/EVENING...TRIGGERING MORE SHRA/TS. THREAT TIME APPEARS TO BE IN THE 20-03Z TIME FRAME AT THE MOMENT. AMPLE ATMOSPHERIC SUPPORT FOR A STRONG-SEVERE STORM THREAT. && .HYDROLOGY... ISSUED AT 331 PM CDT SUN JUL 6 2014 RIVER STAGES ARE FALLING ALONG THE MISSISSIPPI RIVER AND IT APPEARS THAT ALL OF THEM WILL BE BELOW FLOOD STAGE BY THURSDAY. THERE IS SOME RAIN FORECAST OVER THE NEXT FEW DAYS...BUT NONE OF IT LOOKS WIDESPREAD HEAVY ENOUGH TO MAKE A SIGNIFICANT IMPACT ON THE MISSISSIPPI...OR EVEN TRIBUTARIES FOR THAT MATTER. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ MESOSCALE...AJ SHORT TERM..AJ LONG TERM...AJ AVIATION....RIECK HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
331 PM CDT SUN JUL 6 2014 .MESOSCALE DISCUSSION... ISSUED AT 331 PM CDT SUN JUL 6 2014 NUMEROUS SHOWERS AND THUNDERSTORMS CONTINUE TO DEVELOP ALONG AND NORTH OF INTERSTATE 90...ESPECIALLY IN WISCONSIN. THESE ARE ON THE NOSE OF 850MB MOISTURE TRANSPORT AND BASICALLY THE FINE LINE BACK EDGE IS THE 850MB FRONT DEPICTED IN RAP ANALYSIS. THE STRONGEST CORE HAS BEEN OVER TREMPEALEAU COUNTY...AND DOES HAVE SOME MID- LEVEL ROTATION...HOWEVER MUCH OF THE CORE APPEARS TO BE RAIN. NOT ANTICIPATING ANY OF THIS ELEVATED DRIVEN CONVECTION TO TURN SEVERE. FARTHER TO THE WEST...STILL MONITORING FOR SHOWERS AND THUNDERSTORMS TO DEVELOP FROM NORTH CENTRAL IOWA TO SOUTH CENTRAL MN AND WEST CENTRAL WI. SEEING A TOWERING CUMULUS LINE ON VISIBILE IMAGERY...BUT OVERALL DEEP- MOISTURE AND EVEN SURFACE CONVERGENCE ALONG THIS TROUGH IS WEAK. LOOKING AT THE SURFACE FLOW...IT GOES SOUTHWEST AT RST TO NEARLY WEST AT I-35 TO NORTHWEST AT NEW ULM...A LONG DISTANCE. RAP ANALYSIS DOES SHOW 2500-3500 J/KG OF MLCAPE WITH LITTLE CIN IN THIS CORRIDOR...THOUGH. THUS...A WAIT AND SEE IF ANYTHING CAN POP. SHOULD A STORM FIRE...IT WILL PROBABLY TURN SEVERE QUICKLY. NEEDLESS TO SAY...THE COMBINATION OF THE LONG PERIOD OF HAVING THE STRATUS AROUND TODAY AND NOT A LOT OF CONVERGENCE ON THE FRONT HAVE BEEN DETRIMENTAL TO SEVERE POTENTIAL. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 201 PM CDT SUN JUL 6 2014 MAIN SHORT TERM CONCERNS ARE ON CONVECTIVE EVOLUTION AND SEVERE POTENTIAL FOR THIS AFTERNOON/EVENING AND AGAIN LATE MONDAY. CURRENTLY AS OF 19Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED STRONG RIDGING OVER THE WESTERN U.S. WHILE GENERAL WEAK TROUGHING PRESIDED OVER THE GREAT LAKES. A WEAK SHORTWAVE WAS EVIDENT OVER CENTRAL MN. ACCOMPANYING THIS SHORTWAVE PER THE RAP AT 800MB WERE 30 KT NORTHWEST WINDS AND 14-15C TEMPERATURES. COMPARE THIS TO 25-30 KT SOUTHWEST WINDS AND 18-20C TEMPERATURES OVER THE FORECAST AREA. THAT WARM NOSE COMBINED WITH MORNING STRATUS AND DEBRIS CLOUDS HAS KEPT CONDITIONS CAPPED THUS FAR. EDGE OF CAP REFLECTED NICELY TOO BY SOME ELEVATED SHOWERS AND THUNDERSTORMS GOING ON OVER WEST-CENTRAL WISCONSIN. TEMPERATURES FOR THE MOST PART HAVE BEEN STUCK IN THE 70S WITH A FEW 80S WHERE CLEARING BRIEFLY OCCURRED IN SOUTHEAST MN AND WEST CENTRAL WI. DEWPOINTS HAVE BEEN ON THE RISE...THOUGH...NOW IN THE LOW 70S. BACK IN WESTERN IA... EVAPOTRANSPORATION PUSHING DEWPOINTS THERE IN THE UPPER 70S. THINKING THESE HIGHER DEWPOINTS ADVECTING TOWARDS THE AREA IS NOT HELPING MATTERS TO CLEAR THE STRATUS. THE AFOREMENTIONED TEMPERATURES AND DEWPOINTS HAVE RESULTED IN MLCAPE VALUES OF 1500- 2010 J/KG WHILE MLCIN SITS 50-100 J/KG WHERE IT CLEARED TO 201-300 J/KG WHERE ITS STILL CLOUDY. MEANWHILE...IN SOUTHWEST MN... DEWPOINTS HAVE FALLEN OFF INTO MID LOW 50S BEHIND A TROUGH/DRYLINE THAT STRETCHES FROM NORTHWEST IOWA INTO NORTHWEST WI. ANTICIPATING CONVECTION TO FIRE IN THE NEXT 1-2 HOURS ALONG THE TROUGH/DRYLINE NEAR/WEST OF THE FORECAST AREA AS DAYTIME HEATING CONTINUES TO GET RID OF THE CIN. CONVECTION SHOULD TAKE ON A SCATTERED NATURE GIVEN THE CAP IN PLACE. WHERE CONVECTION DOES FIRE...0-3KM AND 0-6KM SHEAR ARE ON THE ORDER OF 20-25KT... WHICH SHOULD FAVOR MORE MULTI-CELLULAR ACTIVITY. GIVEN THE AMOUNT OF CAPE...CANNOT RULE OUT AN INITIAL SUPERCELL...BUT THINKING MORE INTENSE MULTI-CELLS ARE MORE LIKELY. LARGE HAIL AND DAMAGING WINDS WILL BE THE MAIN CONCERNS. GENERAL MODEL CONSENSUS OF BOTH DETERMINISTIC AND HIGH RESOLUTION MODELS SUGGEST MUCH OF THE CONVECTION SHOULD BE SOUTHEAST OF THE FORECAST AREA BY 01-02Z. HOWEVER...THERE IS POTENTIAL THAT THE CONVECTION DOESNT EVEN MAKE IT INTO THE SOUTHEAST END OF THE FORECAST AREA BECAUSE OF THE MASSIVE AMOUNT OF CIN RIGHT NOW IN PLACE. MANY HRRR RUNS TODAY HAVE SHOWN THIS. MUCH OF TONIGHT AND INTO MONDAY MORNING THEN LOOKS DRY AS UNIDIRECTIONAL NORTHWEST FLOW FROM THE SURFACE TO 500MB BRINGS IN SOMEWHAT COOLER AND DRIER AIR IN FROM NORTH DAKOTA. THIS IS REFLECTED WELL IN GOES PRECIPITABLE WATER IMAGERY WHICH SHOWS VALUES OF 1 INCH OR LESS OVER WESTERN MN COMPARED TO 1.5-1.75 INCHES OVER THE FORECAST AREA. HEADING INTO MONDAY AFTERNOON...A LONG WAVE SHORTWAVE TROUGH IS PROGGED TO DROP INTO THE EASTERN DAKOTAS AND WESTERN MN. INCREASING 850MB MOISTURE TRANSPORT AHEAD OF THE TROUGH...COMBINED WITH 1000- 1500 J/KG OF MLCAPE WITH LITTLE CAPPING AND A SURFACE TROUGH MOVING THROUGH...SHOULD RESULT IN A DECENT AMOUNT OF CONVECTION ACROSS MINNESOTA IN THE AFTERNOON HOURS...AS DEPICTED TOO BY DETERMINISTIC AND HIGH RESOLUTION GUIDANCE. THIS CONVECTION COULD SPREAD INTO THE NORTHWEST HALF OF THE FORECAST AREA BY LATE IN THE DAY. GIVEN 0-3KM SHEAR VALUES OF 25-35 KT AND MORE IMPORTANTLY 0-6KM SHEAR VALUES OF 40-55 KT...ORGANIZED SEVERE CONVECTION STILL APPEARS POSSIBLE. COULD END UP SEEING A MIX OF SUPERCELL AND LINE SEGMENTS...THOUGH THE SHEAR BEING UNIDIRECTIONAL MAY FAVOR MORE LINE SEGMENTS AND THUS DAMAGING WINDS. NEED TO WATCH THE LARGE HAIL CONCERN INITIALLY TOO GIVEN LOWER FREEZING LEVELS...DROPPING FROM NEAR 14000 FT THIS AFTERNOON TO 12010 FT LATE MONDAY. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 201 PM CDT SUN JUL 6 2014 MAIN HIGHLIGHTS FOR THE LONG TERM PERIOD ARE SEVERE POTENTIAL MONDAY EVENING FOLLOWED BY COOLER WEATHER FOR MID-WEEK. MONDAY NIGHT...BOTH THE LONG WAVE SHORTWAVE TROUGH AT 500MB AND THE ASSOCIATED SURFACE TROUGH ARE PROGGED TO MOVE SOUTHEAST THROUGH THE REGION. THERE ALSO APPEARS TO BE A POINT IN THE EVENING WHERE WE GET INTO A LEFT EXIT REGION OF AN UPPER JET STREAK. COMBINE THIS DYNAMICAL FORCING WITH AN 850MB MOISTURE TRANSPORT PLUME AND LINGERING INSTABILITY MEANS WE SHOULD BE ABLE TO KEEP SOME SHOWERS AND THUNDERSTORMS GOING THROUGH THE EVENING. UNTIL INSTABILITY WANES...EXPECT A SEVERE THREAT TO EXIST...JUST AS THE 06.12Z HIRES ARW/NMM SUGGEST. MUCH OF THE CONVECTION COULD BE EAST OF THE AREA BY THE OVERNIGHT HOURS...OR AT LEAST OVER THE SOUTHEAST HALF...SO PRECIPITATION DIMINISH NORTHWEST TO SOUTHEAST THROUGH THE NIGHT. PLUS...PRECIPITABLE WATER VALUES TANK AGAIN AFTER BRIEFLY COMING UP MONDAY AFTERNOON. ON TUESDAY...MODEL AGREEMENT IS GOOD ON SETTING UP AN UPPER LEVEL TROUGH FROM NORTHERN ONTARIO SOUTHWARD THROUGH THE WESTERN GREAT LAKES REGION. COOL AIR ALOFT COMBINED WITH A SHORTWAVE DROPPING THROUGH THIS TROUGH IN WISCONSIN...DAYTIME HEATING...AS WELL AS LINGERING LOW LEVEL MOISTURE COULD SPARK SOME DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS. BEST CHANCE FOR THIS WILL BE IN WISCONSIN WITH THE SHORTWAVE DROPPING THROUGH. DRIER WEATHER LOOKS TO PREVAIL TUESDAY NIGHT THROUGH THURSDAY WITH THE FORECAST AREA. THIS IS A RESULT OF A DRIER WESTERN CANADIAN HIGH PRESSURE AREA MOVING THROUGH...AND BEING AROUND THE INFLECTION POINT BEHIND THE WESTERN GREAT LAKES UPPER TROUGH PUSHING OFF TO THE EAST. TEMPERATURES ARE LIKELY TO BE A BIT ON THE COOL SIDE WITH 850MB TEMP ANOMALIES ABOUT 1 STANDARD DEVIATION BELOW NORMAL...OR BETWEEN 9- 13C. LOW PRECIPITABLE WATER AROUND 0.75 INCHES WILL HELP TOO IN RADIATIVE COOLING AT NIGHT...ALONG WITH MIXING OF DEWPOINTS IN THE DAY. COULD SEE SOME VALLEY FOG TUESDAY AND WEDNESDAY NIGHTS. FOR THURSDAY NIGHT INTO THE WEEKEND. WARM ADVECTION BEGINS IN EARNEST THURSDAY NIGHT AS THE HIGH HEADS OFF TO THE EAST. MODEL CONSENSUS IS FOR NUMEROUS SHOWERS AND THUNDERSTORMS TO INITIATE WITH THE MOISTURE RETURN FROM THE UPPER MIDWEST SOUTHWARD INTO THE CENTRAL PLAINS...PERHAPS CREEPING INTO THE FORECAST AREA EITHER LATE THURSDAY NIGHT OR DURING THE DAY FRIDAY. STORM CHANCES THEN LOOK TO CONTINUE THROUGH SATURDAY AS AN UPPER TROUGH DROPS SOUTH FROM MANITOBA INTO THE WESTERN GREAT LAKES REGION. PERHAPS BY SUNDAY ALL THE CONVECTIVE POTENTIAL WILL GET SHOVED TO THE SOUTH AS THE UPPER TROUGH CONTINUES TO DIG SOUTHEASTWARD. HOWEVER...HAVE STILL MAINTAINED CHANCES OF SHOWERS AND THUNDERSTORMS ACROSS SOUTHERN PORTIONS OF THE FORECAST AREA. TEMPERATURE WISE...850MB TEMPS GENERALLY RANGE 16-18C THROUGH SATURDAY...SUPPORTING HIGHS IN THE 80S. THESE SHOULD COOL BACK SOME ON SUNDAY WITH THE TROUGH DROPPING IN. HUMIDITY WILL BE UP TOO FRIDAY AND SATURDAY WITH THAT RETURN FLOW...EVAPOTRANSPORATION AND POTENTIAL CONVECTION ADDING MOISTURE TO THE BOUNDARY LAYER. && .AVIATION...(FOR THE 18Z TAFS...THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1220 PM CDT SUN JUL 6 2014 MVFR/IFR STRATUS DECK FINALLY BREAKING/SCATTERING AS OF MID DAY. WITH DIURNAL WARMING AND SOUTHWEST 10-20KT WINDS FOR MIXING...EXPECT THIS TO CONTINUE THRU THE AFTERNOON WITH RISING CLOUD HGTS. A FRONTAL BOUNDARY FROM NEAR KDLH TO KFSD WILL MOVE RATHER QUICKLY SOUTHEAST AND ACROSS THE TAF SITES THIS AFTERNOON/EARLY THIS EVENING. FRONT WILL TRIGGER A SCT-BKN LINE OF SHRA/TSRA AS IT MOVES ACROSS...MAINLY IN THE 20-22Z PERIOD AT KRST AND 22-24Z AT KLSE. MAIN CONVECTION STILL LOOKS TO DEVELOP JUST EAST OF KRST SO LEFT THAT AS PERIOD OF VCTS. CONTINUED WITH 2SM TSRA AT KLSE...BUT IF TSRA END UP MORE SCATTERED IN THE LINE...VCTS MAY BE MORE APPROPRIATE FOR THIS PERIOD AT KLSE. ONCE FRONT GOES THRU...DEW POINTS DROP ABOUT 10F AS DRIER AIR SPREADS IN. WEST-NORTHWEST WINDS OF 5-10KTS THEN KEEP THE BOUNDARY LAYER STIRRED TONIGHT...AND ANY LATE NIGHT/EARLY MORNING BR TO A MINIMUM. GOOD VFR CONDITIONS EXPECTED TONIGHT THRU MON MORNING. ANOTHER ROUND OF SHRA/TSRA WITH MVFR/IFR CIGS/VSBYS IS SLATED TO SPREAD INTO THE TAF SITES LATER MON AFTERNOON/EVENING. && .HYDROLOGY... ISSUED AT 331 PM CDT SUN JUL 6 2014 RIVER STAGES ARE FALLING ALONG THE MISSISSIPPI RIVER AND IT APPEARS THAT ALL OF THEM WILL BE BELOW FLOOD STAGE BY THURSDAY. THERE IS SOME RAIN FORECAST OVER THE NEXT FEW DAYS...BUT NONE OF IT LOOKS WIDESPREAD HEAVY ENOUGH TO MAKE A SIGNIFICANT IMPACT ON THE MISSISSIPPI...OR EVEN TRIBUTARITES FOR THAT MATTER. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ MESOSCALE...AJ SHORT TERM...AJ LONG TERM...AJ AVIATION.....DAS HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
201 PM CDT SUN JUL 6 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 201 PM CDT SUN JUL 6 2014 MAIN SHORT TERM CONCERNS ARE ON CONVECTIVE EVOLUTION AND SEVERE POTENTIAL FOR THIS AFTERNOON/EVENING AND AGAIN LATE MONDAY. CURRENTLY AS OF 19Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED STRONG RIDGING OVER THE WESTERN U.S. WHILE GENERAL WEAK TROUGHING PRESIDED OVER THE GREAT LAKES. A WEAK SHORTWAVE WAS EVIDENT OVER CENTRAL MN. ACCOMPANYING THIS SHORTWAVE PER THE RAP AT 800MB WERE 30 KT NORTHWEST WINDS AND 14-15C TEMPERATURES. COMPARE THIS TO 25-30 KT SOUTHWEST WINDS AND 18-20C TEMPERATURES OVER THE FORECAST AREA. THAT WARM NOSE COMBINED WITH MORNING STRATUS AND DEBRIS CLOUDS HAS KEPT CONDITIONS CAPPED THUS FAR. EDGE OF CAP REFLECTED NICELY TOO BY SOME ELEVATED SHOWERS AND THUNDERSTORMS GOING ON OVER WEST-CENTRAL WISCONSIN. TEMPERATURES FOR THE MOST PART HAVE BEEN STUCK IN THE 70S WITH A FEW 80S WHERE CLEARING BRIEFLY OCCURRED IN SOUTHEAST MN AND WEST CENTRAL WI. DEWPOINTS HAVE BEEN ON THE RISE...THOUGH...NOW IN THE LOW 70S. BACK IN WESTERN IA... EVAPOTRANSPORATION PUSHING DEWPOINTS THERE IN THE UPPER 70S. THINKING THESE HIGHER DEWPOINTS ADVECTING TOWARDS THE AREA IS NOT HELPING MATTERS TO CLEAR THE STRATUS. THE AFOREMENTIONED TEMPERATURES AND DEWPOINTS HAVE RESULTED IN MLCAPE VALUES OF 1500- 2010 J/KG WHILE MLCIN SITS 50-100 J/KG WHERE IT CLEARED TO 201-300 J/KG WHERE ITS STILL CLOUDY. MEANWHILE...IN SOUTHWEST MN... DEWPOINTS HAVE FALLEN OFF INTO MID LOW 50S BEHIND A TROUGH/DRYLINE THAT STRETCHES FROM NORTHWEST IOWA INTO NORTHWEST WI. ANTICIPATING CONVECTION TO FIRE IN THE NEXT 1-2 HOURS ALONG THE TROUGH/DRYLINE NEAR/WEST OF THE FORECAST AREA AS DAYTIME HEATING CONTINUES TO GET RID OF THE CIN. CONVECTION SHOULD TAKE ON A SCATTERED NATURE GIVEN THE CAP IN PLACE. WHERE CONVECTION DOES FIRE...0-3KM AND 0-6KM SHEAR ARE ON THE ORDER OF 20-25KT... WHICH SHOULD FAVOR MORE MULTI-CELLULAR ACTIVITY. GIVEN THE AMOUNT OF CAPE...CANNOT RULE OUT AN INITIAL SUPERCELL...BUT THINKING MORE INTENSE MULTI-CELLS ARE MORE LIKELY. LARGE HAIL AND DAMAGING WINDS WILL BE THE MAIN CONCERNS. GENERAL MODEL CONSENSUS OF BOTH DETERMINISTIC AND HIGH RESOLUTION MODELS SUGGEST MUCH OF THE CONVECTION SHOULD BE SOUTHEAST OF THE FORECAST AREA BY 01-02Z. HOWEVER...THERE IS POTENTIAL THAT THE CONVECTION DOESNT EVEN MAKE IT INTO THE SOUTHEAST END OF THE FORECAST AREA BECAUSE OF THE MASSIVE AMOUNT OF CIN RIGHT NOW IN PLACE. MANY HRRR RUNS TODAY HAVE SHOWN THIS. MUCH OF TONIGHT AND INTO MONDAY MORNING THEN LOOKS DRY AS UNIDIRECTIONAL NORTHWEST FLOW FROM THE SURFACE TO 500MB BRINGS IN SOMEWHAT COOLER AND DRIER AIR IN FROM NORTH DAKOTA. THIS IS REFLECTED WELL IN GOES PRECIPITABLE WATER IMAGERY WHICH SHOWS VALUES OF 1 INCH OR LESS OVER WESTERN MN COMPARED TO 1.5-1.75 INCHES OVER THE FORECAST AREA. HEADING INTO MONDAY AFTERNOON...A LONG WAVE SHORTWAVE TROUGH IS PROGGED TO DROP INTO THE EASTERN DAKOTAS AND WESTERN MN. INCREASING 850MB MOISTURE TRANSPORT AHEAD OF THE TROUGH...COMBINED WITH 1000- 1500 J/KG OF MLCAPE WITH LITTLE CAPPING AND A SURFACE TROUGH MOVING THROUGH...SHOULD RESULT IN A DECENT AMOUNT OF CONVECTION ACROSS MINNESOTA IN THE AFTERNOON HOURS...AS DEPICTED TOO BY DETERMINISTIC AND HIGH RESOLUTION GUIDANCE. THIS CONVECTION COULD SPREAD INTO THE NORTHWEST HALF OF THE FORECAST AREA BY LATE IN THE DAY. GIVEN 0-3KM SHEAR VALUES OF 25-35 KT AND MORE IMPORTANTLY 0-6KM SHEAR VALUES OF 40-55 KT...ORGANIZED SEVERE CONVECTION STILL APPEARS POSSIBLE. COULD END UP SEEING A MIX OF SUPERCELL AND LINE SEGMENTS...THOUGH THE SHEAR BEING UNIDIRECTIONAL MAY FAVOR MORE LINE SEGMENTS AND THUS DAMAGING WINDS. NEED TO WATCH THE LARGE HAIL CONCERN INITIALLY TOO GIVEN LOWER FREEZING LEVELS...DROPPING FROM NEAR 14000 FT THIS AFTERNOON TO 12010 FT LATE MONDAY. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 201 PM CDT SUN JUL 6 2014 MAIN HIGHLIGHTS FOR THE LONG TERM PERIOD ARE SEVERE POTENTIAL MONDAY EVENING FOLLOWED BY COOLER WEATHER FOR MID-WEEK. MONDAY NIGHT...BOTH THE LONG WAVE SHORTWAVE TROUGH AT 500MB AND THE ASSOCIATED SURFACE TROUGH ARE PROGGED TO MOVE SOUTHEAST THROUGH THE REGION. THERE ALSO APPEARS TO BE A POINT IN THE EVENING WHERE WE GET INTO A LEFT EXIT REGION OF AN UPPER JET STREAK. COMBINE THIS DYNAMICAL FORCING WITH AN 850MB MOISTURE TRANSPORT PLUME AND LINGERING INSTABILITY MEANS WE SHOULD BE ABLE TO KEEP SOME SHOWERS AND THUNDERSTORMS GOING THROUGH THE EVENING. UNTIL INSTABILITY WANES...EXPECT A SEVERE THREAT TO EXIST...JUST AS THE 06.12Z HIRES ARW/NMM SUGGEST. MUCH OF THE CONVECTION COULD BE EAST OF THE AREA BY THE OVERNIGHT HOURS...OR AT LEAST OVER THE SOUTHEAST HALF...SO PRECIPITATION DIMINISH NORTHWEST TO SOUTHEAST THROUGH THE NIGHT. PLUS...PRECIPITABLE WATER VALUES TANK AGAIN AFTER BRIEFLY COMING UP MONDAY AFTERNOON. ON TUESDAY...MODEL AGREEMENT IS GOOD ON SETTING UP AN UPPER LEVEL TROUGH FROM NORTHERN ONTARIO SOUTHWARD THROUGH THE WESTERN GREAT LAKES REGION. COOL AIR ALOFT COMBINED WITH A SHORTWAVE DROPPING THROUGH THIS TROUGH IN WISCONSIN...DAYTIME HEATING...AS WELL AS LINGERING LOW LEVEL MOISTURE COULD SPARK SOME DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS. BEST CHANCE FOR THIS WILL BE IN WISCONSIN WITH THE SHORTWAVE DROPPING THROUGH. DRIER WEATHER LOOKS TO PREVAIL TUESDAY NIGHT THROUGH THURSDAY WITH THE FORECAST AREA. THIS IS A RESULT OF A DRIER WESTERN CANADIAN HIGH PRESSURE AREA MOVING THROUGH...AND BEING AROUND THE INFLECTION POINT BEHIND THE WESTERN GREAT LAKES UPPER TROUGH PUSHING OFF TO THE EAST. TEMPERATURES ARE LIKELY TO BE A BIT ON THE COOL SIDE WITH 850MB TEMP ANOMALIES ABOUT 1 STANDARD DEVIATION BELOW NORMAL...OR BETWEEN 9- 13C. LOW PRECIPITABLE WATER AROUND 0.75 INCHES WILL HELP TOO IN RADIATIVE COOLING AT NIGHT...ALONG WITH MIXING OF DEWPOINTS IN THE DAY. COULD SEE SOME VALLEY FOG TUESDAY AND WEDNESDAY NIGHTS. FOR THURSDAY NIGHT INTO THE WEEKEND. WARM ADVECTION BEGINS IN EARNEST THURSDAY NIGHT AS THE HIGH HEADS OFF TO THE EAST. MODEL CONSENSUS IS FOR NUMEROUS SHOWERS AND THUNDERSTORMS TO INITIATE WITH THE MOISTURE RETURN FROM THE UPPER MIDWEST SOUTHWARD INTO THE CENTRAL PLAINS...PERHAPS CREEPING INTO THE FORECAST AREA EITHER LATE THURSDAY NIGHT OR DURING THE DAY FRIDAY. STORM CHANCES THEN LOOK TO CONTINUE THROUGH SATURDAY AS AN UPPER TROUGH DROPS SOUTH FROM MANITOBA INTO THE WESTERN GREAT LAKES REGION. PERHAPS BY SUNDAY ALL THE CONVECTIVE POTENTIAL WILL GET SHOVED TO THE SOUTH AS THE UPPER TROUGH CONTINUES TO DIG SOUTHEASTWARD. HOWEVER...HAVE STILL MAINTAINED CHANCES OF SHOWERS AND THUNDERSTORMS ACROSS SOUTHERN PORTIONS OF THE FORECAST AREA. TEMPERATURE WISE...850MB TEMPS GENERALLY RANGE 16-18C THROUGH SATURDAY...SUPPORTING HIGHS IN THE 80S. THESE SHOULD COOL BACK SOME ON SUNDAY WITH THE TROUGH DROPPING IN. HUMIDITY WILL BE UP TOO FRIDAY AND SATURDAY WITH THAT RETURN FLOW...EVAPOTRANSPORATION AND POTENTIAL CONVECTION ADDING MOISTURE TO THE BOUNDARY LAYER. && .AVIATION...(FOR THE 18Z TAFS...THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1220 PM CDT SUN JUL 6 2014 MVFR/IFR STRATUS DECK FINALLY BREAKING/SCATTERING AS OF MID DAY. WITH DIURNAL WARMING AND SOUTHWEST 10-20KT WINDS FOR MIXING...EXPECT THIS TO CONTINUE THRU THE AFTERNOON WITH RISING CLOUD HGTS. A FRONTAL BOUNDARY FROM NEAR KDLH TO KFSD WILL MOVE RATHER QUICKLY SOUTHEAST AND ACROSS THE TAF SITES THIS AFTERNOON/EARLY THIS EVENING. FRONT WILL TRIGGER A SCT-BKN LINE OF SHRA/TSRA AS IT MOVES ACROSS...MAINLY IN THE 20-22Z PERIOD AT KRST AND 22-24Z AT KLSE. MAIN CONVECTION STILL LOOKS TO DEVELOP JUST EAST OF KRST SO LEFT THAT AS PERIOD OF VCTS. CONTINUED WITH 2SM TSRA AT KLSE...BUT IF TSRA END UP MORE SCATTERED IN THE LINE...VCTS MAY BE MORE APPROPRIATE FOR THIS PERIOD AT KLSE. ONCE FRONT GOES THRU...DEW POINTS DROP ABOUT 10F AS DRIER AIR SPREADS IN. WEST-NORTHWEST WINDS OF 5-10KTS THEN KEEP THE BOUNDARY LAYER STIRRED TONIGHT...AND ANY LATE NIGHT/EARLY MORNING BR TO A MINIMUM. GOOD VFR CONDITIONS EXPECTED TONIGHT THRU MON MORNING. ANOTHER ROUND OF SHRA/TSRA WITH MVFR/IFR CIGS/VSBYS IS SLATED TO SPREAD INTO THE TAF SITES LATER MON AFTERNOON/EVENING. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION.....DAS