Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/24/14


AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
952 AM MDT SUN JUN 22 2014 .UPDATE... ISSUED AT 933 AM MDT SUN JUN 22 2014 WATER VAPOR IMAGERY SHOWING WEAK UPPER LEVEL WAVE OVER THE GREAT BASIN WHICH WILL MOVE OVER COLORADO THIS AFTERNOON AND EVENING AND WILL PROVIDE SOME WEAK ASCENT. OVERALL MOISTURE VALUES ARE TRENDING SLIGHTLY HIGHER THAN YESTERDAY AT THIS TIME WITH SURFACE DEWPOINTS NOW IN THE UPPER 40S TO THE MID 50S OVER LOWER ELEVATIONS. LATEST ACARS SOUNDINGS SHOWING SUBSTANTIAL CAP AROUND 750 MB SO FURTHER HEATING NEEDED. THUNDERSTORM DEVELOPMENT MAY BE A BIT LATER THIS AFTERNOON THAN YESTERDAY GIVEN HIGHER INITIAL STABILITY. NOT A LOT OF MODEL CONSENSUS WITH STORM INITIATION TODAY AS NAM/RAP SHOWING MUCH OF THE STORMS ALONG A OUTFLOW BOUNDARY/FRONT WHICH BACKS INTO NORTHEAST COLORADO FROM NEBRASKA LATER THIS AFTERNOON. MEANWHILE THE HRRR HAS A MORE WEST TO EAST PROGRESSION OF STORMS THIS AFTERNOON. MAIN CHANGE TO FORECAST WAS TO LOWER POPS A BIT OVER MOUNTAINS AND FOOTHILLS. && .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 200 AM MDT SUN JUN 22 2014 MESSY SURFACE PATTERN THIS MORNING...BUT GENERAL TREND OF PRESSURE RISES TO OUR NORTH. EDGE OF COOLER/MOISTER AIR ALONG THE EDGE OF OUTFLOW FROM SEVERAL ROUNDS OF STORMS ACROSS WYOMING/NEBRASKA... ROUGHLY AKRON TO TORRINGTON AND NORTHWEST FROM THERE. PRESSURE RISES APPEAR TO BE BETTER ORGANIZED AGAIN AT THE MOMENT...SO THE IDEA OF THIS BOUNDARY MOVING SOUTH ACROSS THE AREA THIS MORNING STILL LOOKS GOOD. AT FIRST THIS AIR WILL BE COOLER...WITH A LOW LEVEL INVERSION HOLDING BACK CONVECTION THIS MORNING. SEVERAL THINGS HAPPEN THIS AFTERNOON THAT SHOULD EVENTUALLY RESULT IN DECENT THUNDERSTORM COVERAGE. FIRST...LIFT AND A LITTLE COOLING ALOFT MOVES IN FROM THE WEST...DESTABILIZING THE DEEPER ATMOSPHERE. SECOND...CONTINUED DEEPENING OF THE SURFACE COOL LAYER WHICH WILL ERODE THE LOW LEVEL CAP. THIRD...LIKELY OUTFLOW FROM ADDITIONAL CONVECTION NORTH OF US WHICH SHOULD PROVIDE BETTER MOISTURE FROM THE NEBRASKA PANHANDLE. THIS WILL INCREASE CAPE VALUES AND WIPE OUT THE CAP LATE IN THE DAY. ENVIRONMENT WILL EVENTUALLY HAVE MORE MOISTURE THAN THE LAST FEW DAYS...BUT THE BIGGEST DIFFERENCE WILL BE THE INCREASING SHEAR AS THE DAY GOES ON. BY THIS EVENING THE 0-6 KM SHEAR WILL BE UP AROUND 40 KNOTS. CAPE VALUES SHOULD BE IN THE 1000-1500 J/KG RANGE BUT WITH THAT AMOUNT OF SHEAR THIS SHOULD BE ENOUGH FOR SEVERE HAIL PRODUCTION...AND EVENTUALLY TO ALLOW ENOUGH ORGANIZATION FOR SOME WIND THREAT AS WELL. INITIALLY THE NORTH SIDE OF STORMS WILL BE FAVORED...COULD BE CONVECTION MOVING NORTHEAST OFF OF THE FOOTHILLS AND THE FRONTAL BOUNDARY...OR STORMS THAT SPLIT WITH THE LEFT SIDE FAVORED. LATER THIS EVENING THE SHEAR WILL BECOME MORE LINEAR...WITH CONVERGENCE ON THE FRONT HELPING KEEP THINGS MOVING DESPITE SLOW MEAN WINDS AROUND 10 KNOTS. SOME CONCERN ABOUT INCREASING MOISTURE AND INSTABILITY WITH SLOW STORM MOTIONS...BUT OVERALL WIND PATTERN DOES NOT APPEAR TO LEND ITSELF TO TRAINING/BACKBUILDING WITH THE POSSIBLE EXCEPTION OF REGENERATION OVER THE FOOTHILLS. SEE HYDROLOGY SECTION BELOW FOR MORE. SOME OF THE MODELS WANT TO END CONVECTION EARLY THIS EVENING...I AM SKEPTICAL OF THIS GIVEN THAT THE UPSLOPE FLOW SHOULD BE CONTINUING INTO THE EVENING AND THE POTENTIAL FOR MOIST OUTFLOW TO GENERATE NEW CONVECTION. I SHIFTED THE POPS MORE TO THE LATE AFTERNOON AND EVENING PERIODS WHERE IT APPEARS THE BEST MOISTURE AND INSTABILITY SHOULD BE. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 200 AM MDT SUN JUN 22 2014 MONDAY AND MONDAY NIGHT...A MODERATE NORTHWESTERLY FLOW ALOFT WILL BE OVER NORTHERN CO WITH AN UPPER RIDGE TO THE WEST. AT THE SFC...HIGH PRESSURE WILL BE OVER THE NORTHEAST PLAINS WITH ELY WINDS ADVECTING BETTER MOISTURE INTO THE URBAN CORRIDOR. FORECAST SOUNDINGS IN THE AFTN SHOW GOOD INSTABILITY WITH CAPES AROUND 1100 J/KG AROUND DENVER AND AKRON...WITH HIGHER VALUES OF 1600 J/KG AT LIMON. PW VALUES CLIMB TO AROUND 1 INCH OVER THE NERN PLAINS AND NEAR 0.75 INCHES IN DENVER. FAVORABLE SHEAR PROFILE FOR SEVERE THUNDERSTORMS IN THE AFTN AND EVENING WITH DAMAGING WINDS AND LARGE HAIL THE MAIN THREATS. LOW LEVEL ESELY WINDS WL LIKELY SET UP A DENVER CYCLONE WITH THE POTENTIAL FOR A WEAK LANDSPOUT OR TWO ALONG THE BOUNDARY. MDLS CONTINUE TO PRODUCE SOME QPF ACROSS THE NERN PLAINS OVERNIGHT. NOT MUCH CHANGE REALLY FOR TUESDAY...THE FLOW ALOFT MAY BE A BIT WEAKER AND SLIGHTLY WARMER TEMPERATURES WILL ALLOW FOR GREATER INSTABILITY IN THE AFTN. WITH THE HIGHER PW VALUES AND SLOWER STORM MOTIONS...THE POTENTIAL FOR HEAVY RAIN PRODUCING TSTMS WILL ADD TO THE ALREADY PRESENT SEVERE TSTM THREAT. THE UPPER LEVEL RIDGE WILL TRANSITION ACROSS ERN CO BY WEDNESDAY...WITH A DRIER SOUTHWESTERLY FLOW ALOFT OVER COLORADO. IN THE LOWER LEVELS...THERE MAY BE SOME DRYING ALONG THE URBAN CORRIDOR...BUT THE NERN PLAINS WILL REMAIN MOIST. BEST TSTMS COVERAGE WILL BE EAST OF THE I-25 CORRIDOR...WITH LESSENING POPS TO THE WEST. THE TREND FOR WARMER AND DRIER CONDITIONS WILL CONTINUE FOR THURSDAY AND FRIDAY. COOLER CONDITIONS ARE THEN PROGGED TO RETURN BY SATURDAY. THE MDLS VARY QUITE A BIT WITH THE OVERALL PATTERN AS THE NEXT SYSTEM FM THE PAC NORTHWEST BRINGS COOLER WEATHER WITH A BETTER CHANCE FOR TSTMS. THE GFS KEEPS THIS SYSTEM MORE TO THE NORTH LATE FRIDAY INTO SATURDAY...WHILE THE ECMWF AND CANADIAN MDLS ARE SLOWER AND DIG THE TROUGH INTO THE GREAT BASIN ON FRIDAY. NO CHANGES TO THE GRIDS AT THIS TIME...WL KEEP POPS ON THE LOW SIDE WITH SO MUCH UNCERTAINTY PRESENT. && .AVIATION...(FOR THE TAFS THROUGH 18Z MONDAY MORNING) ISSUED AT 933 AM MDT SUN JUN 22 2014 THERE IS SOME LIGHT NORTHWEST WINDS AT LOCAL TERMINALS BUT THE FORECAST OF NORTHEAST WINDS AT 18Z MAY NOT MATERIALIZE AS FRONTAL BOUNDARY WAS WEAKER THAN EXPECTED. THERE COULD BE A STRONGER FRONTAL PUSH LATER THIS AFTERNOON WITH ADDITIONAL STORMS BUT OVERALL CONFIDENCE IS LOW. OVERALL WON`T CHANGE MUCH WITHOUT A CLEAR SIGNAL. && .HYDROLOGY... ISSUED AT 200 AM MDT SUN JUN 22 2014 INCREASED MOISTURE AND INSTABILITY TODAY WILL COMBINE WITH SLOW STORM MOTIONS TO PRODUCE A THREAT OF HEAVY RAINFALL. IN GENERAL THUNDERSTORMS ARE EXPECTED TO BE MOVING...BUT SLOWLY. RAINFALL AMOUNTS OF UP TO AN INCH IN AN HOUR ARE POSSIBLE WITH THE STRONGER STORMS NEAR THE FRONT RANGE THIS AFTERNOON. ON THE PLAINS MOISTURE WILL BE GREATER BY THIS EVENING...WITH 2 TO 3 INCHES IN 1 TO 2 HOURS POSSIBLE. THE HEAVIER END OF THESE AMOUNTS MAY BE ENOUGH TO CAUSE FLASH FLOODING. WHILE THE HEAVY RAIN THREAT IS MAINLY ON THE PLAINS...THERE IS SOME THREAT TO THE FRONT RANGE FOOTHILLS... ESPECIALLY BETWEEN 3 PM AND 9 PM WHEN THERE COULD BE SUSTAINED EASTERLY WINDS THAT COULD PRODUCE REPEATED THUNDERSTORM CELLS. WITH LIMITED MOISTURE AND NO CLEAR FOCUS...AT THIS TIME THE THREAT DOES NOT APPEAR HIGH ENOUGH TO WARRANT A FLASH FLOOD WATCH. AREAS WEST OF THE FRONT RANGE WILL HAVE LESS MOISTURE. FOR MONDAY AND TUESDAY...A STATIONARY FRONT WILL BE PARKED ALONG THE FRONT RANGE AND PALMER DIVIDE WITH WEAK ESELY SFC WINDS. HIGHER PW VALUES WILL BE PRESENT. THE STORM MOTIONS ON MONDAY WILL HELP TO OFFSET THE HEAVY RAIN POTENTIAL SOMEWHAT. SLIGHTLY LESSER STORM MOTIONS ON TUESDAY MAY ELEVATE THE POTENTIAL FOR FLASH FLOODING. IT WILL DRY OUT FROM THE URBAN CORRIDOR WESTWARD ON WEDNESDAY... BUT POTENTIAL FOR HEAVIER RAIN PRODUCING TSTMS WL CONTINUE OVER THE NORTHEAST PLAINS. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...ENTREKIN SHORT TERM...GIMMESTAD LONG TERM...COOPER AVIATION...ENTREKIN HYDROLOGY...COOPER/GIMMESTAD
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
847 PM EDT MON JUN 23 2014 .UPDATE...ACTIVITY TO PERSIST A FEW MORE HOURS NORTH OF ALMA GA AND FLAGLER TO SRN MARION COUNTIES...OTHERWISE PARTLY CLOUDY SKIES TONIGHT. CURRENT LOW TEMP FORECAST LOOKS FINE. && .AVIATION...VFR CONDITIONS FORECAST AT TAF SITES. LATEST HRRR CEILING GUIDANCE HINTS AT POTENTIAL FOR PATCHY LOW CLOUDS FOR A FEW HOURS TOWARD DAWN. 00Z SOUNDINGS SHOWS SOMEWHAT DRIER AIR 700-900 MB LAYER...SO LOW CONFIDENCE IN LOW CLOUDS AT THIS POINT...NEXT SHIFT WILL NEED TO LOOK AT THIS POTENTIAL FOR NEXT TAF ISSUANCE. && .MARINE...SOUTH TO SOUTHWEST WINDS 10 KTS AND 2-3 FT SEAS EXPECTED TONIGHT AND TUESDSAY...NO CHANGES PLANNED IN NEXT CWF ISSUANCE. RIP CURRENTS: LOW RISK THRU TUESDAY. && .PRELIMINARY POINT TEMPS/POPS... AMG 71 90 70 94 / 30 60 60 50 SSI 75 86 74 90 / 20 60 60 40 JAX 71 91 72 93 / 10 60 60 50 SGJ 73 88 73 89 / 20 60 60 40 GNV 70 90 71 93 / 20 60 50 40 OCF 71 90 71 93 / 40 50 40 40 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && $$ WOLF/STRUBLE/WALKER
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1254 PM CDT SUN JUN 22 2014 .DISCUSSION... 1126 AM CDT MAIN UPDATES THIS MORNING WERE TO ADD SLIGHT CHANCE FOR THUNDER ACROSS THE WESTERN CWA LATE THIS AFTERNOON AND EARLY EVENING. STRATUS AND FOG CONTINUE TO LIFT/DISSIPATE LATE THIS MORNING WITH SKIES BECOMING MORE PARTLY CLOUDY TO AT TIMES PARTLY SUNNY. TEMPERATURES ARE STEADILY REBOUNDING AND WILL RISE INTO THE MID 80S THIS AFTERNOON FOR MOST AREAS...WHILE DEWPOINTS REMAIN IN THE 60S AND STILL PROVIDING FOR SOME MUGGY CONDITIONS. NOT OVERLY CONCERNED AT THIS TIME...BUT AM DEFINITELY WATCHING COMPLEX OF THUNDERSTORMS MOVING EAST ACROSS EAST CENTRAL IOWA. MOST GUIDANCE THIS MORNING HAS THIS COMPLEX REACHING THE FAR WESTERN CWA BY EARLY EVENING...BUT RAPIDLY WEAKENING AT THAT TIME. THIS SCENARIO DOES SEEM POSSIBLE AS INSTABILITY IN PLACE WOULD BE LOWERING. IF THIS COMPLEX OF STORMS WERE TO TAKE ON A MORE STEADY PACE EASTWARD TODAY...THEY COULD BE NEAR THE FAR WESTERN CWA BY LATE THIS AFTERNOON. THIS WOULD BE CONCERNING AS HIGH DEWPOINT AIR POOLING ALONG A LINGERING BOUNDARY/TROUGH AXIS AS WELL AS STEEP LOW LEVEL LAPSE RATES FORECAST TO BE IN PLACE COULD AID IN ISOLATED STRONG THUNDERSTORM DEVELOPMENT IN THE WESTERN CWA...PRIMARILY ALONG AND WEST OF INTERSTATE 39. THE UNCERTAINTIES IN PLACE HAVE PRECLUDED ANY HIGHER WORDING FOR THUNDERSTORM POTENTIAL IN THE HWO AS WELL AS HIGHER POPS OUT WEST BEYOND THE ADDED SLIGHT CHANCE. WILL CLOSELY MONITOR THIS POTENTIAL AND MAKE NECESSARY UPDATES OVER THE NEXT COUPLE OF HOURS AS NEED BE. RODRIGUEZ //PREV DISCUSSION... 348 AM CDT A RATHER CHALLENGING FORECAST TONIGHT WITH RESPECT TO SENSIBLE WEATHER DETAILS...ESPECIALLY WITH RESPECT TO PCPN CHANCES OVER THE NEXT SEVERAL DAYS. THE ENVIRONMENT REMAINS VERY MOIST...WITH PWATS OF 1.5 TO ALMOST 2.0 INCHES ACROSS THE MIDWEST...UPPER MIDWEST AND GREAT LAKES REGION... WHILE A VERY WEAK GRADIENT SFC PATTERN COVERS THE REGION. IN THE ABSENCE OF ANY SIGNIFICANT SFC FORCING...ANY CONVECTIVE ACTIVITY OVER THE NEXT SEVERAL DAYS WILL LARGELY RELY ON UPPER LEVEL FORCING AS THE SURFACE REFLECTION OF UPPER LEVELS FEATURES WILL BE RATHER WEAK. FOR THE REMAINDER OF THE NIGHT AND INTO SUNDAY MORNING...THE MAIN ISSUE WILL BE FOG AND STRATUS DEVELOPMENT IN THE WAKE OF ANOTHER ROUND OF THUNDERSTORMS AND HEAVY RAIN THAT SWEPT THROUGH THE REGION SATURDAY AFTERNOON AND EVENING. LATEST SATELLITE FOG IMAGERY HAD INDICATED AN AREA OF LOW STRATUS AND FOG SPREADING OFF THE LAKE INTO NERN IL. WITH CI OBSCURING ANY LOW FEATURES IN THE SATELLITE IMAGERY...HAVE FOLLOWED SFC OB TRENDS...WHICH GENERALLY INDICATE LOW STRATUS OVER MUCH OF THE CWA NORTH OF THE I-80 CORRIDOR. HAVE HELD OFF ON ISSUING A DENSE FOG ADVISORY FOR NOW SINCE THE DENSE FOG APPEARS TO BE RATHER SPOTTY. WITH MORE HIGH CLOUD OVERSPREADING THE REGION...THE CHANCES FOR WIDESPREAD AREAS OF FOG WITH VIS AT OR LESS THAN 1/4SM SEEMS LIMITED. FOR THE REMAINDER OF SUNDAY...HAVE BACKED OFF ON POPS OVER ALL OF THE CWA WITH THE EXCEPTION OF THE FAR SOUTH AS THE AREA RECOVERS FROM EARLIER CONVECTION. A VERY WEAK AND DIFFUSE QUASI-STATIONARY FRONT REMAINS DRAPED ACROSS NRN/CNTRL IL INTO THE OHIO VALLEY AND LINGERING OUTFLOW BOUNDARIES COULD IGNITE SOME TSRA/SHRA TODAY...AND SHOULD BE LIMITED TO THE FAR SOUTHERN PORTIONS OF THE CWA WHICH WILL NOT SEE THE STRATUS AND FOG. ANOTHER CONCERN FOR THIS AFTERNOON WILL BE ANOTHER LAKE BREEZE MOVING INLAND. WITH A VERY WEAK GRADIENT IN PLACE...LAKE BREEZE DEVELOPMENT IS LIKELY...ESPECIALLY IF NERON IL CAN BURN OFF THE STRATUS AND FOR EARLY ENOUGH TO SET UP ADEQUATE DIFFERENTIAL HEATING BETWEEN THE COLD LAKE AND WARMER LAND. IF THIS DOES OCCUR...ADDITION FOG TRAPPED UNDER A MARINE LAYER INVERSION WOULD LIKELY PUSH INLAND BEHIND THE BOUNDARY. SO..WHILE IT WOULD BE CLIMATOLOGICALLY UNUSUAL TO THINK ABOUT INTRODUCING FOG AND/OR STRATUS INTO THE FORECAST FOR THE AFTERNOON HOURS...THE UNUSUALLY COLD LAKE WATERS MAKE THIS A DISTINCT POSSIBILITY. ANTICIPATE THAT THE REST OF SUNDAY AND SUNDAY EVENING SHOULD BE DRY...WITH THE NEXT SIGNIFICANT CHANCE FOR PCPN NOT COMING UNTIL LATE SUNDAY NIGHT. WITH AN UPPER LOW REMAINING NEARLY STATIONARY OVER LAKE WINNIPEG AND BROAD HIGH PRESSURE ACROSS THE SRN CONUS AND THE GLFMEX...WEAK ZONAL FLOW CONTINUES ALOFT...WITH A SERIES OF WEAK SHORTWAVES RIPPLING THROUGH THE NORTHERN PLAINS AND INTO THE GREAT LAKES REGION. AS IS TYPICAL FOR ZONAL FLOW...TIMING INDIVIDUAL SHORTWAVES IS VERY DIFFICULT...BUT THE GLOBAL MODELS HAVE BEEN RELATIVELY CONSISTENT ON TRACKING A MODERATE SHORTWAVE ACROSS THE NORTHERN PLAINS TO THE UPPER MISSISSIPPI VALLEY BY THIS EVENING. THIS FEATURE SHOULD THEN CROSS THE REGION LATE SUNDAY NIGHT AND MONDAY MORNING...BRINGING THE NEXT SIGNIFICANT CHANCE FOR SHOWERS AND THUNDERSTORMS. THIS FEATURE IS RESPONSIBLE FOR THE ONGOING CONVECTION OVER THE CENTRAL PLAINS AND IS WELL INITIALIZED IN THE GLOBAL MODELS...SO IN DEFERENCE TO GOOD INITIALIZATION AND THE RELATIVELY DECENT MODEL CONTINUITY...HAVE GONE WITH CATEGORICAL POPS AS THE SYSTEM CROSSES THE REGION. ENVIRONMENTAL CONDITIONS WILL BE FAVORABLE FOR LOCALLY HEAVY RAINFALL...WITH PWATS AROUND 1.75 INCHES AND WEAK STEERING FLOW AS THE SYSTEM CROSSES THE REGION. AS THERE HAS BEEN A CONSIDERABLE AMOUNT OF RAIN OVER THE REGION IN RECENT DAYS...THE GROUND IS LARGELY SATURATED AND AREA RIVERS HAVE LESS CAPACITY FROM THE RESULTANT RUNOFF...SO THE POTENTIAL FOR FLOODING WILL NEED TO BE CONSIDERED. THERE IS A SMALL SEVERE THREAT WITH THESE THUNDERSTORMS AS THE ENVIRONMENT WILL BE MOIST AND UNSTABLE...AWAY FROM THE STABILIZATION OF THE LAKE BREEZE/MARINE LAYER MOVING INLAND. THE MAIN SHORTWAVE AND THE ASSOCIATED WEAK SFC FRONT IS EXPECTED TO PUSH THROUGH THE REGION BY TUESDAY. FROM TUESDAY THROUGH THE REMAINDER OF THE FORECAST PERIOD...FORECAST CONFIDENCE DECREASES RAPIDLY. THE UPPER LOW OVER CANADA IS EXPECTED TO SHOW LITTLE PROGRESSION WITH A SERIES OF WEAK SHORTWAVES RIPPLING THROUGH THE ZONAL FLOW ALOFT OVER THE REGION. WHILE THE MODELS GENERALLY AGREE THAT THERE WILL BE LITTLE CHANGE TO THE LOW AMPLITUDE PATTERN ALOFT...TIMING ANY OF THE SHORTWAVES RIPPLING THROUGH THE FLOW WILL BE DIFFICULT. SO...WHILE THE FORECAST FROM TUESDAY EVENING THROUGH THE END OF THE FORECAST PERIOD...SATURDAY...MAY SOUND LIKE A BROKEN RECORD (AT LEAST TO THOSE OF US OLD ENOUGH TO REMEMBER RECORDS AND WHAT THEY SOUND LIKE WHEN BROKEN)...THERE WILL BE LITTLE CHANGE TO THE IN SITU CONDITIONS WITH DEEP LAYER MOISTURE IN PLACE...ANY MID LEVEL FORCING FROM PASSING SHORTWAVES WILL BE ADEQUATE TO GENERATE SHOWERS AND THUNDERSTORMS. SO...WILL CARRY SLIGHT CHANCE TO CHANCE POPS THROUGH MUCH OF THE REMAINDER OF THE FORECAST PERIOD. KREIN && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * INCREASING CHANCE OF SHRA/TSRA TONIGHT AND TOMORROW. * EAST TO NORTHEAST WIND NEAR THRESHOLD OF STAYING ON WEST FLOW FOR ORD. LENNING //DISCUSSION...UPDATED 18Z... THE CLUSTER OF SHOWERS AND THUNDERSTORMS MOVING ACROSS IOWA TODAY HAS NOT BEEN WELL HANDLED BY ALL MODELS...SO IT IS HARD TO PIN DOWN THE EXPECTED EVOLUTION INTO THIS EVENING AND OVERNIGHT. GIVEN THE DEGREE OF INSTABILITY...IT IS QUITE POSSIBLE THESE WILL HANG TOGETHER INTO THE WESTERN PORTION OF THE FCST AREA AND REACH RFD BY LATE AFTERNOON TO EARLY EVENING. LOSS OF DIURNAL HEATING LATER THIS EVENING MAY DAMPEN CONVECTION SOMEWHAT AFTER SUNDOWN AS THEY WORK INTO THE CHICAGO METRO AREA. EVEN SO...HAVE MOVED UP START TIME OF VCSH AT ORD/MDW TERMINALS. GIVEN THE DEEP AND MOIST BUT RELATIVELY WARM VERTICAL TEMPERATURE AND MOISTURE PROFILE...NOT CERTAIN HOW MUCH THUNDER THE AREA WILL SEE AHEAD OF A FRONTAL PASSAGE TOWARD MIDDAY TOMORROW...BUT INCLUDED A WINDOW OF VCTS CORRESPONDING TO APPROXIMATE TIME OF FROPA. AS FOR WINDS...EXPECT GRADUAL VEERING THROUGH THE PERIOD...WITH A TURN TOWARD WESTERLY AFTER FROPA TOMORROW. LIGHT SPEEDS FOR MOST OF THE AFTERNOON MAY ALLOW CONTINUED WEST FLOW CONFIGURATION AT ORD...BUT SPEEDS ARE EXPECTED TO INCREASE A COUPLE OF KTS AS THE AFTERNOON PROGRESSES. LENNING //ORD AND MDW CONFIDENCE...UPDATED 18Z... * MEDIUM CONFIDENCE IN SHRA TIMING TONIGHT AND TOMORROW. * MEDIUM TO HIGH CONFIDENCE IN WINDS. LENNING //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT...TSRA LIKELY. TUESDAY...CHANCE OF SHRA. WEDNESDAY...SLIGHT CHANCE OF SHRA. THURSDAY-SATURDAY...CHANCE OF SHRA AND SLIGHT CHANCE OF TSRA. MTF && .MARINE... 205 AM CDT A LIGHT PRESSURE GRADIENT WILL BE SEEN OVER LAKE MICHIGAN TODAY DUE TO EXPANSIVE HIGH PRESSURE CENTERED OVER THE EASTERN LAKES INTO NEW ENGLAND. THIS REGIME OFFERS ONSHORE FLOW INTO ILLINOIS AND INDIANA THAT SHOULD INCREASE TO AROUND 10 TO 15 KT DURING MIDDAY BEFORE DIMINISHING BY SUNDOWN. THIS SETUP WILL ALSO ALLOW DENSE FOG TO CONTINUE ACROSS MUCH OF THE LAKE AS THERE WILL BE LITTLE TURNOVER OF THE MOIST AIRMASS OVER THE COOL WATERS. LOW PRESSURE WILL APPROACH THE LAKE ON MONDAY AND EVENTUALLY MOVE OVER THE NORTHERN PART OF IT MONDAY NIGHT. SOUTHERLY FLOW IS EXPECTED IN ADVANCE OF THIS AND COULD PUSH THE FOG FURTHER NORTH ON MONDAY. IN ADDITION...THUNDERSTORM CHANCES WILL INCREASE AND COULD DISRUPT SOME OF THE FOG AS WELL. SO HAVE NOT EXTENDED THE DENSE FOG ADVISORY ANY FURTHER THAN MONDAY MORNING AT THIS TIME...ALTHOUGH FOR NORTHERN AND CENTRAL PORTIONS OF THE LAKE IT MAY NEED TO BE. THE SYSTEM COLD FRONT WILL LIKELY PASS VERY EARLY TUESDAY MORNING AND TURN WINDS WESTERLY. A SECOND COLD FRONT...MORE OF A BACKDOOR ONE...IS ANTICIPATED TO PROGRESS SOUTHWARD TUESDAY NIGHT AND LEAD TO NORTHERLY WINDS. MTF && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...DENSE FOG ADVISORY...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563- LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741- LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870- LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 10 AM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1224 PM CDT Sun Jun 22 2014 .DISCUSSION... ISSUED 1005 AM CDT Sun Jun 22 2014 Convection developed just southwest of our CWA earlier this morning, along the remnants of the outflow boundary from yesterday`s storms. Latest surface map shows this boundary arcing northwest along the Mississippi River then into central Iowa, where a line of strong storms was moving through that area. Have been seeing some increase in showers recently along this boundary in the northeast corner of Missouri, and this should increase over the next few hours. Latest RAP and HRRR guidance showing the western CWA still with the best chances for showers/storms today, with some more isolated activity across the east. Have updated the zones/grids to reflect the storms mainly being during the afternoon, as well as some adjustments to the sky cover. Temperatures are largely in good shape and only required some minor adjustments over the next few hours. Geelhart && .AVIATION... ISSUED 1222 PM CDT Sun Jun 22 2014 Scattered convection has developed over western Illinois and is slowly moving east. AWIPS timing tools would place it in the KPIA/KSPI area in the 20-21Z time frame, but some uncertainty in the eastward progression, so will limit afternoon VCTS mention to these two sites at the moment, and bring them into KBMI/KDEC toward 00Z. A larger area of showers and scattered storms is expected to move through after 06Z. Then after a short break beginning near sunrise, additional convective development is anticipated toward the end of the forecast period, as a cold front moves in from the northwest. Geelhart && .PREV DISCUSSION... ISSUED 330 AM CDT Sun Jun 22 2014 Though an area of showers and thunderstorms moved across much of ILX yesterday evening, the air mass overall remains very much the same. Hot and humid conditions persist. A weak frontal boundary has meandered just north of the area and the next couple of impulses are just to the west, lining up for arrival later today. In between waves, much of this morning may be dry in most locations. Not taking out the possibility for some very isolated showers...but chances will increase this afternoon/later this evening with the approach of the next wave. Surface low associated with the next wave is weak and as a result, models are not doing well with its evolution in the weak pattern as a whole. Models continue to over produce the coverage of the convection, then suffer the feedback issues. Chance/slight chance dominates, with some minor adjustments for drier pds. Temps above normal and heat indices in the 90s to wrap up the weekend until the next cool front moves through Mon/Mon afternoon. SHORT TERM...Today and tonight... Hot. Humid. Heat indices into the mid 90s and chances of precip increasing into the afternoon/evening hours. Waves to the west showing varied paths and models connecting the dots on the qpf leave a lot to be desired. Waves passing north and south remain a possibility, but diurnal impacts and enhancement is just too strong a possibility with leftover outflows in the region to NOT have pops around this evening. Very similar tune to the trend from the past few days. Coverage sporadic, plenty of ingredients to work with, just non consistent triggers. LONG TERM...Monday through Friday... Upper trof/wave pushing through the region on Monday into Tuesday bringing signif chance, increasing from Sun night into Monday night. Models speeding up with initial arrival of boundary on Monday, and slowing its departure...as this run has been a little more diffuse with the pops and may see this trending with a +/- 12 hrs on either side. Not an absolute at this point, but Monday/Monday night having the best chances at significant precip through the fcst. A slightly cooler Tuesday through the end of the week. Still warm, but potentially less humidity as winds become more westerly on Tuesday, picking up a northerly component by Wednesday. Forecast trending drier from late Tuesday through Wednesday. Another wave Thursday brings back some pops ahead of the next big storm system developing over the SW for late next weekend. HJS && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1109 AM CDT SUN JUN 22 2014 .DISCUSSION... 348 AM CDT A RATHER CHALLENGING FORECAST TONIGHT WITH RESPECT TO SENSIBLE WEATHER DETAILS...ESPECIALLY WITH RESPECT TO PCPN CHANCES OVER THE NEXT SEVERAL DAYS. THE ENVIRONMENT REMAINS VERY MOIST...WITH PWATS OF 1.5 TO ALMOST 2.0 INCHES ACROSS THE MIDWEST...UPPER MIDWEST AND GREAT LAKES REGION... WHILE A VERY WEAK GRADIENT SFC PATTERN COVERS THE REGION. IN THE ABSENCE OF ANY SIGNIFICANT SFC FORCING...ANY CONVECTIVE ACTIVITY OVER THE NEXT SEVERAL DAYS WILL LARGELY RELY ON UPPER LEVEL FORCING AS THE SURFACE REFLECTION OF UPPER LEVELS FEATURES WILL BE RATHER WEAK. FOR THE REMAINDER OF THE NIGHT AND INTO SUNDAY MORNING...THE MAIN ISSUE WILL BE FOG AND STRATUS DEVELOPMENT IN THE WAKE OF ANOTHER ROUND OF THUNDERSTORMS AND HEAVY RAIN THAT SWEPT THROUGH THE REGION SATURDAY AFTERNOON AND EVENING. LATEST SATELLITE FOG IMAGERY HAD INDICATED AN AREA OF LOW STRATUS AND FOG SPREADING OFF THE LAKE INTO NERN IL. WITH CI OBSCURING ANY LOW FEATURES IN THE SATELLITE IMAGERY...HAVE FOLLOWED SFC OB TRENDS...WHICH GENERALLY INDICATE LOW STRATUS OVER MUCH OF THE CWA NORTH OF THE I-80 CORRIDOR. HAVE HELD OFF ON ISSUING A DENSE FOG ADVISORY FOR NOW SINCE THE DENSE FOG APPEARS TO BE RATHER SPOTTY. WITH MORE HIGH CLOUD OVERSPREADING THE REGION...THE CHANCES FOR WIDESPREAD AREAS OF FOG WITH VIS AT OR LESS THAN 1/4SM SEEMS LIMITED. FOR THE REMAINDER OF SUNDAY...HAVE BACKED OFF ON POPS OVER ALL OF THE CWA WITH THE EXCEPTION OF THE FAR SOUTH AS THE AREA RECOVERS FROM EARLIER CONVECTION. A VERY WEAK AND DIFFUSE QUASI-STATIONARY FRONT REMAINS DRAPED ACROSS NRN/CNTRL IL INTO THE OHIO VALLEY AND LINGERING OUTFLOW BOUNDARIES COULD IGNITE SOME TSRA/SHRA TODAY...AND SHOULD BE LIMITED TO THE FAR SOUTHERN PORTIONS OF THE CWA WHICH WILL NOT SEE THE STRATUS AND FOG. ANOTHER CONCERN FOR THIS AFTERNOON WILL BE ANOTHER LAKE BREEZE MOVING INLAND. WITH A VERY WEAK GRADIENT IN PLACE...LAKE BREEZE DEVELOPMENT IS LIKELY...ESPECIALLY IF NERON IL CAN BURN OFF THE STRATUS AND FOR EARLY ENOUGH TO SET UP ADEQUATE DIFFERENTIAL HEATING BETWEEN THE COLD LAKE AND WARMER LAND. IF THIS DOES OCCUR...ADDITION FOG TRAPPED UNDER A MARINE LAYER INVERSION WOULD LIKELY PUSH INLAND BEHIND THE BOUNDARY. SO..WHILE IT WOULD BE CLIMATOLOGICALLY UNUSUAL TO THINK ABOUT INTRODUCING FOG AND/OR STRATUS INTO THE FORECAST FOR THE AFTERNOON HOURS...THE UNUSUALLY COLD LAKE WATERS MAKE THIS A DISTINCT POSSIBILITY. ANTICIPATE THAT THE REST OF SUNDAY AND SUNDAY EVENING SHOULD BE DRY...WITH THE NEXT SIGNIFICANT CHANCE FOR PCPN NOT COMING UNTIL LATE SUNDAY NIGHT. WITH AN UPPER LOW REMAINING NEARLY STATIONARY OVER LAKE WINNIPEG AND BROAD HIGH PRESSURE ACROSS THE SRN CONUS AND THE GLFMEX...WEAK ZONAL FLOW CONTINUES ALOFT...WITH A SERIES OF WEAK SHORTWAVES RIPPLING THROUGH THE NORTHERN PLAINS AND INTO THE GREAT LAKES REGION. AS IS TYPICAL FOR ZONAL FLOW...TIMING INDIVIDUAL SHORTWAVES IS VERY DIFFICULT...BUT THE GLOBAL MODELS HAVE BEEN RELATIVELY CONSISTENT ON TRACKING A MODERATE SHORTWAVE ACROSS THE NORTHERN PLAINS TO THE UPPER MISSISSIPPI VALLEY BY THIS EVENING. THIS FEATURE SHOULD THEN CROSS THE REGION LATE SUNDAY NIGHT AND MONDAY MORNING...BRINGING THE NEXT SIGNIFICANT CHANCE FOR SHOWERS AND THUNDERSTORMS. THIS FEATURE IS RESPONSIBLE FOR THE ONGOING CONVECTION OVER THE CENTRAL PLAINS AND IS WELL INITIALIZED IN THE GLOBAL MODELS...SO IN DEFERENCE TO GOOD INITIALIZATION AND THE RELATIVELY DECENT MODEL CONTINUITY...HAVE GONE WITH CATEGORICAL POPS AS THE SYSTEM CROSSES THE REGION. ENVIRONMENTAL CONDITIONS WILL BE FAVORABLE FOR LOCALLY HEAVY RAINFALL...WITH PWATS AROUND 1.75 INCHES AND WEAK STEERING FLOW AS THE SYSTEM CROSSES THE REGION. AS THERE HAS BEEN A CONSIDERABLE AMOUNT OF RAIN OVER THE REGION IN RECENT DAYS...THE GROUND IS LARGELY SATURATED AND AREA RIVERS HAVE LESS CAPACITY FROM THE RESULTANT RUNOFF...SO THE POTENTIAL FOR FLOODING WILL NEED TO BE CONSIDERED. THERE IS A SMALL SEVERE THREAT WITH THESE THUNDERSTORMS AS THE ENVIRONMENT WILL BE MOIST AND UNSTABLE...AWAY FROM THE STABILIZATION OF THE LAKE BREEZE/MARINE LAYER MOVING INLAND. THE MAIN SHORTWAVE AND THE ASSOCIATED WEAK SFC FRONT IS EXPECTED TO PUSH THROUGH THE REGION BY TUESDAY. FROM TUESDAY THROUGH THE REMAINDER OF THE FORECAST PERIOD...FORECAST CONFIDENCE DECREASES RAPIDLY. THE UPPER LOW OVER CANADA IS EXPECTED TO SHOW LITTLE PROGRESSION WITH A SERIES OF WEAK SHORTWAVES RIPPLING THROUGH THE ZONAL FLOW ALOFT OVER THE REGION. WHILE THE MODELS GENERALLY AGREE THAT THERE WILL BE LITTLE CHANGE TO THE LOW AMPLITUDE PATTERN ALOFT...TIMING ANY OF THE SHORTWAVES RIPPLING THROUGH THE FLOW WILL BE DIFFICULT. SO...WHILE THE FORECAST FROM TUESDAY EVENING THROUGH THE END OF THE FORECAST PERIOD...SATURDAY...MAY SOUND LIKE A BROKEN RECORD (AT LEAST TO THOSE OF US OLD ENOUGH TO REMEMBER RECORDS AND WHAT THEY SOUND LIKE WHEN BROKEN)...THERE WILL BE LITTLE CHANGE TO THE IN SITU CONDITIONS WITH DEEP LAYER MOISTURE IN PLACE...ANY MID LEVEL FORCING FROM PASSING SHORTWAVES WILL BE ADEQUATE TO GENERATE SHOWERS AND THUNDERSTORMS. SO...WILL CARRY SLIGHT CHANCE TO CHANCE POPS THROUGH MUCH OF THE REMAINDER OF THE FORECAST PERIOD. KREIN && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * LIGHT EAST TO NORTHEAST WINDS. * SHRA/TSRA POTENTIAL INCREASES OVERNIGHT INTO TOMORROW MORNING. LENNING //DISCUSSION...UPDATED 12Z... ANOTHER LATE JUNE MORNING OF UNCLIMATOLOGICALLY FAVORED DENSE FOG AND STRATUS OVER/NEAR THE TAF SITES. A LIGHT PRESSURE GRADIENT IN PLACE UNDER HIGH PRESSURE HAS ALLOWED FOR THIS FOG AND STRATUS...PARTLY ENHANCED AGAIN BY THE MARINE LAYER OFF COOL LAKE MICHIGAN. THIS SHOULD DISSIPATE NEAR A SIMILAR TIME AS YESTERDAY...AS THE STRATUS LAYER LOOKS TO BE FAIRLY SHALLOW. ONSHORE FLOW WILL CONTINUE TODAY WITH A SLIGHT INCREASE TO NEAR 10 KT THIS AFTERNOON. THE CONTINUED ONSHORE FLOW THIS EVENING MAY AGAIN BRING IN FOG OR STRATUS AFTER DARK. SOUTHERLY FLOW AND HIGH CLOUDS MOVING IN TONIGHT ARE EXPECTED TO PREVENT THE FOG FROM GETTING AS AGGRESSIVE AS THE PAST FEW DAYS. WARM AIR ADVECTION TONIGHT AHEAD OF THE NEXT LOW PRESSURE SYSTEM SHOULD SPREAD SHOWERS AND STORMS NORTHEAST TOWARD THE AREA. THESE MAY OVERSPREAD THE TERMINALS PRIOR TO DAYBREAK. CONFIDENCE IS LOW OVERALL IN THAT TAF ASPECT...BUT THINK MONDAY MORNING WILL AT LEAST SEE SHOWERS WITH EMBEDDED THUNDER. //ORD AND MDW CONFIDENCE...UPDATED 16Z... * MEDIUM TO HIGH CONFIDENCE ON WIND DIRECTION AND SPEEDS TODAY. * MEDIUM CONFIDENCE ON SHRA/TSRA START TIME TONIGHT AND TOMORROW. LENNING //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT...TSRA LIKELY. TUESDAY...CHANCE OF SHRA. WEDNESDAY...SLIGHT CHANCE OF SHRA. THURSDAY-SATURDAY...CHANCE OF SHRA AND SLIGHT CHANCE OF TSRA. MTF && .MARINE... 205 AM CDT A LIGHT PRESSURE GRADIENT WILL BE SEEN OVER LAKE MICHIGAN TODAY DUE TO EXPANSIVE HIGH PRESSURE CENTERED OVER THE EASTERN LAKES INTO NEW ENGLAND. THIS REGIME OFFERS ONSHORE FLOW INTO ILLINOIS AND INDIANA THAT SHOULD INCREASE TO AROUND 10 TO 15 KT DURING MIDDAY BEFORE DIMINISHING BY SUNDOWN. THIS SETUP WILL ALSO ALLOW DENSE FOG TO CONTINUE ACROSS MUCH OF THE LAKE AS THERE WILL BE LITTLE TURNOVER OF THE MOIST AIRMASS OVER THE COOL WATERS. LOW PRESSURE WILL APPROACH THE LAKE ON MONDAY AND EVENTUALLY MOVE OVER THE NORTHERN PART OF IT MONDAY NIGHT. SOUTHERLY FLOW IS EXPECTED IN ADVANCE OF THIS AND COULD PUSH THE FOG FURTHER NORTH ON MONDAY. IN ADDITION...THUNDERSTORM CHANCES WILL INCREASE AND COULD DISRUPT SOME OF THE FOG AS WELL. SO HAVE NOT EXTENDED THE DENSE FOG ADVISORY ANY FURTHER THAN MONDAY MORNING AT THIS TIME...ALTHOUGH FOR NORTHERN AND CENTRAL PORTIONS OF THE LAKE IT MAY NEED TO BE. THE SYSTEM COLD FRONT WILL LIKELY PASS VERY EARLY TUESDAY MORNING AND TURN WINDS WESTERLY. A SECOND COLD FRONT...MORE OF A BACKDOOR ONE...IS ANTICIPATED TO PROGRESS SOUTHWARD TUESDAY NIGHT AND LEAD TO NORTHERLY WINDS. MTF && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...DENSE FOG ADVISORY...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563- LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741- LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870- LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 10 AM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1005 AM CDT Sun Jun 22 2014 .DISCUSSION... ISSUED 1005 AM CDT Sun Jun 22 2014 Convection developed just southwest of our CWA earlier this morning, along the remnants of the outflow boundary from yesterday`s storms. Latest surface map shows this boundary arcing northwest along the Mississippi River then into central Iowa, where a line of strong storms was moving through that area. Have been seeing some increase in showers recently along this boundary in the northeast corner of Missouri, and this should increase over the next few hours. Latest RAP and HRRR guidance showing the western CWA still with the best chances for showers/storms today, with some more isolated activity across the east. Have updated the zones/grids to reflect the storms mainly being during the afternoon, as well as some adjustments to the sky cover. Temperatures are largely in good shape and only required some minor adjustments over the next few hours. Geelhart && .AVIATION... ISSUED 651 AM CDT Sun Jun 22 2014 Weak high pressure over IL will provide light and variable winds with light fog early this morning. Ground fog has generally remained clear of the TAF sites, but is lingering in nearby fields per surrounding observations. Will keep all TAF sites VFR this morning as a result. Next concern is when storms will develop over the next 24 hours. There remains a large spread in the model guidance on storm initiation and coverage. The GFS remains the most aggressive with storms later this afternoon and evening. The 00z NAM, Canadian, and ECMWF have slowed down the development of storms until possibly later tonight, and mainly west of I-55. The HRRR 3km model is still indicating a line of storms reaching near the IL river by 00z this evening, but is the outlier of the latest runs of the high res models. Will only include a VCSH later tonight after 09z for now. Would not be surprised to see a pop-up shower or storm late this afternoon and evening. Winds will remain generally light and variable due to a weak pressure gradient. Some southerly winds may develop for PIA and SPI as the next shortwave aloft approaches IL this afternoon. Wind speeds should remain less than 10kt at all terminal sites. Shimon && .PREV DISCUSSION... ISSUED 330 AM CDT Sun Jun 22 2014 Though an area of showers and thunderstorms moved across much of ILX yesterday evening, the air mass overall remains very much the same. Hot and humid conditions persist. A weak frontal boundary has meandered just north of the area and the next couple of impulses are just to the west, lining up for arrival later today. In between waves, much of this morning may be dry in most locations. Not taking out the possibility for some very isolated showers...but chances will increase this afternoon/later this evening with the approach of the next wave. Surface low associated with the next wave is weak and as a result, models are not doing well with its evolution in the weak pattern as a whole. Models continue to over produce the coverage of the convection, then suffer the feedback issues. Chance/slight chance dominates, with some minor adjustments for drier pds. Temps above normal and heat indices in the 90s to wrap up the weekend until the next cool front moves through Mon/Mon afternoon. SHORT TERM...Today and tonight... Hot. Humid. Heat indices into the mid 90s and chances of precip increasing into the afternoon/evening hours. Waves to the west showing varied paths and models connecting the dots on the qpf leave a lot to be desired. Waves passing north and south remain a possibility, but diurnal impacts and enhancement is just too strong a possibility with leftover outflows in the region to NOT have pops around this evening. Very similar tune to the trend from the past few days. Coverage sporadic, plenty of ingredients to work with, just non consistent triggers. LONG TERM...Monday through Friday... Upper trof/wave pushing through the region on Monday into Tuesday bringing signif chance, increasing from Sun night into Monday night. Models speeding up with initial arrival of boundary on Monday, and slowing its departure...as this run has been a little more diffuse with the pops and may see this trending with a +/- 12 hrs on either side. Not an absolute at this point, but Monday/Monday night having the best chances at significant precip through the fcst. A slightly cooler Tuesday through the end of the week. Still warm, but potentially less humidity as winds become more westerly on Tuesday, picking up a northerly component by Wednesday. Forecast trending drier from late Tuesday through Wednesday. Another wave Thursday brings back some pops ahead of the next big storm system developing over the SW for late next weekend. HJS && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
102 PM CDT SUN JUN 22 2014 .UPDATE... ISSUED AT 100 PM CDT SUN JUN 22 2014 SEVERE THUNDERSTORM WATCH IN EFFECT FOR MUCH OF THE DVN CWA UNTIL 7 PM THIS EVENING. LINE OF THUNDERSTORMS IN OUR NW CWA MOVING INTO SBCAPES OF 3000-4000 J/KG. THIS LINE HAS ALREADY PRODUCED STRONG WINDS AND ISOLATED HAIL ALONG WITH VERY HEAVY RAINFALL. HAD A REPORT OF 2.40 INCHES OF RAIN IN BENTON COUNTY WITH THIS LINE. OTHER STORMS WERE DEVELOPING IN SOUTHERN IA AND NORTHERN MO AND WILL UPSCALE THIS AFTERNOON. UPDATE ISSUED AT 1004 AM CDT SUN JUN 22 2014 HAVE INCREASED POPS WEST OF THE MS RIVER AS MCS CONTINUES TO MAKE SLOW BUT STEADY PROGRESS ACROSS CENTRAL IA. PLENTY OF SUNSHINE IN EASTERN IA AHEAD OF THE MCS WITH SBCAPES ALREADY NEARING 3000 J/KG WITH DCAPE ALSO INCREASING. SPC HAS ADDED EASTERN IA TO A SLIGHT RISK FOR THIS AFTERNOON WITH DAMAGING WIND THE MAIN THREAT WITH MARGINAL SEVERE HAIL ALSO. STORMS WILL BE MOVING RATHER SLOWLY SO TORRENTIAL RAINS WILL ALSO BE A CONCERN AS PRECIPITABLE WATERS INCREASE TO OVER 1.50 INCHES. THERE WILL BE THE POTENTIAL FOR LOCALIZED FLASH FLOODING ESPECIALLY WHERE HEAVY RAINS HAVE FALLEN IN THE PAST WEEK. && .SYNOPSIS... ISSUED AT 249 AM CDT SUN JUN 22 2014 LATEST SFC ANALYSIS SHOWS SURFACE LOW OVER SOUTH CENTRAL NE WITH A WEAK STATIONARY FRONT STRETCHING ACROSS NORTHERN SECTIONS OF THE CWFA. DEW POINTS HOLDING IN THE 60S AND LIGHT WINDS IN THE FRONTAL ZONE SUPPORTING FOG DEVELOPMENT ALONG HWY 20 CORRIDOR IN PARTICULAR. ALOFT...NEAR ZONAL FLOW ACROSS THE CENTRAL US AT 500MB WITH WEAK RIDGING OVER THE UPPER MISSISSIPPI VALLEY. FESTERING WEAK CONVECTION VICINITY LSX AND MORE VIGOROUS STORMS OVER NW IA CURRENTLY HEADED EAST-SOUTHEASTWARD. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 249 AM CDT SUN JUN 22 2014 MAIN FORECAST CONCERN IN THE SHORT TERM IS POTENTIAL PRECIP TODAY. RECENT MODEL SOLUTIONS REGARDING PRECIPITATION HAVE BEEN LARGELY OVERDONE...THUS OVERALL CONFIDENCE IN SHORT TERM MODEL SOLUTIONS IS LOWER THAN NORMAL. ECMWF FOR EXAMPLE GROSSLY OVERFORECAST FORCING AND PRECIP YESTERDAY. THUS...FOR SHORT TERM WILL RELY ON BLEND OF THIS MORNINGS MORE CONSERVATIVE HRRR...NAM...AND RUC. STORMS CURRENTLY OVER NORTHWEST IA ARE HINTED AT BY HRRR AND RUC. BOTH AGREE WITH WEAKENING TREND AS THE CONVECTION COMES UP AGAINST THE UPPER RIDGE. GIVEN THIS EXPECTATION...THE MOST LIKELY OPPORTUNITY FOR RAIN LOCALLY WILL COME THIS AFTERNOON AS THE UPPER RIDGE SLIDES A BIT FARTHER EAST AND A SHORT WAVE PUSHES INTO WESTERN IA. CONVECTION SHOULD FIRE IN CENTRAL IA AND PUSH EAST INTO WESTERN SECTIONS OF THE CWFA THIS AFTERNOON. AS A RESULT...RAIN CHANCES HAVE BEEN LOWERED ACROSS THE BOARD FOR THIS MORNING AND SHIFTED A BIT WEST FOR THE AFTERNOON. PRECIP CHANCES WILL CONTINUE OVERNIGHT AS WEAK CYCLONIC FLOW AND A STRONGER SHORT WAVE OVERTAKE THE REGION. DMD .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 249 AM CDT SUN JUN 22 2014 MONDAY INTO MONDAY EVENING STILL ON TRACK FOR BEST PCPN CHCS IN NEXT FEW DAYS. MODELS CONTINUE TO DIVERGE ON WHETHER ANY PHASING OCCURS BETWEEN SOUTHERN CANADA SHORTWAVE AND ENERGY RIPPLING IN UNDERCUTTING QUASI-ZONAL FLOW... WITH MOST OF RECENT MODELS NOW SHOWING NO PHASING. PHASING WILL HAVE SIGNIFICANT IMPACTS ON PCPN AMOUNTS AND COVERAGE... AS MORE PHASED SCENARIO WOULD SUPPORT MCS WITH WIDESPREAD HEAVIER RAINS OF 1-3+ INCHES. BUT... ATTIM THE FCST IS TRENDING LOWER ON QPF AMOUNTS AND HARBORS SOME UNCERTAINTY ON PCPN COVERAGE MONDAY INTO MONDAY EVENING GIVEN LACK OF PHASING SUGGESTED BY MOST MODEL SOLUTIONS. THE CONCERN WITH NO PHASING IS THE POTENTIAL FOR SOME OF AREA TO BE SPLIT BY BETTER COVERAGE WITH ONE DISTURBANCE AND MORE CONCENTRATED BATCH OF CONVECTION LIFTING NORTHEASTWARD INTO UPPER MIDWEST AND AWAY FROM CWA... WHILE ANOTHER DISTURBANCE AND MORE ORGANIZED CONVECTION SHIFTS E/SE ACROSS PORTIONS OF SOUTH CENTRAL PLAINS DIVING INTO BEST INSTABILITY AND MOISTURE AXIS. WITH THAT BEING SAID... GIVEN HIGH PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES AND DECENT UPPER DIFFLUENCE WOULD ANTICIPATE STILL GOOD COVERAGE OF SHOWERS/STORMS ON MONDAY WITH RISK OF LOCALLY HEAVY RAIN. PCPN SHOULD TAPER OFF WEST TO EAST MONDAY EVENING WITH PASSAGE OF COLD FRONT. TUE-TUE NIGHT... SLIGHTLY COOLER AND DRIER CONDITIONS APPEAR ON TAP WITH WEAK SUBSIDENCE IN WAKE OF FRONT. WED-SAT... PATTERN SET TO RETURN UNSETTLED/ACTIVE WITH SEVERAL DISTURBANCES POSSIBLY IN QUASI-ZONAL FLOW BEFORE TRANSITION TO SOUTHWEST FLOW ALOFT LATE IN THE PERIOD AHEAD OF WESTERN CONUS TROUGH. SHOULD SEE A BIT OF AN UPTICK IN BOTH TEMPS AND HUMIDITY BY LATE WEEK AND ESPECIALLY NEXT WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 100 PM CDT SUN JUN 22 2014 VFR CONDS THROUGH THIS TAF CYCLE BUT MVFR/BRIEF IFR CONDS IN THUNDERSTORMS. SCATTERED TO LINES OF THUNDERSTORMS THIS AFTERNOON THEN MORE THUNDERSTORMS OVERNIGHT INTO MONDAY MORNING. SOUTH WINDS LESS THAN 10 KNOTS BUT MUCH HIGHER IN THUNDERSTORMS. && .HYDROLOGY... ISSUED AT 249 AM CDT SUN JUN 22 2014 AREA TRIBUTARY RIVERS MAINLY NORTH OF I-80...AS WELL AS THE MAINSTEM MISSISSIPPI RIVER WILL CONTINUE TO RISE INTO NEXT WEEK IN RESPONSE TO RECENT HEAVY RAINFALL. THE POTENTIAL FOR LOCALLY HEAVY RAINFALL EXISTS NEXT 36-48 HRS...WITH BEST CHANCES FOR PCPN AND HEAVY RAINFALL LATE TONIGHT AND MONDAY. SOME GOOD NEWS THIS AM IN THAT WHAT WAS LOOKING LIKE POTENTIAL FOR WIDESPREAD SIGNIFICANT RAINFALL 1-3+ INCHES NOW MORE LOCALIZED POTENTIAL AS MODELS HAVE GENERALLY BACKED OFF TO A WEAKER STORM SYSTEM IMPACTING THE AREA. WOULD LIKE TO STRESS THAT WHILE THIS IS THE CASE THIS AM... THIS IS FAR FROM CERTAIN AND COULD CHANGE AS MODELS CONTINUALLY DIVERGING... THUS CAUTIOUS OPTIMISM THAT HIGHER QPF AMOUNTS MORE LOCALIZED AND NOT AS WIDESPREAD. RIVER SITES THAT ARE CURRENTLY UNDER A WARNING ARE FORECAST TO SEE MINOR TO MODERATE FLOODING...WITH THE EXCEPTION OF THE MISSISSIPPI RIVER AT BURLINGTON...WHERE MAJOR FLOODING IS FORECAST. HOWEVER...SHOULD A HEAVY SOAKING RAIN OF 1 TO 3+ INCHES OCCUR OVER ANY RIVER BASINS NEXT COUPLE OF DAYS...THEN RENEWED RISES AND HIGHER CREST LEVELS WOULD BE LIKELY. THOSE WITH INTERESTS ON AREA RIVERS OR WHO WOULD BE IMPACTED BY HIGH WATER LEVELS SHOULD PAY VERY CLOSE ATTENTION NEXT COUPLE OF DAYS. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...HAASE SYNOPSIS...DMD SHORT TERM...DMD LONG TERM...05 AVIATION...HAASE HYDROLOGY...05
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1004 AM CDT SUN JUN 22 2014 .UPDATE... ISSUED AT 1004 AM CDT SUN JUN 22 2014 HAVE INCREASED POPS WEST OF THE MS RIVER AS MCS CONTINUES TO MAKE SLOW BUT STEADY PROGRESS ACROSS CENTRAL IA. PLENTY OF SUNSHINE IN EASTERN IA AHEAD OF THE MCS WITH SBCAPES ALREADY NEARING 3000 J/KG WITH DCAPE ALSO INCREASING. SPC HAS ADDED EASTERN IA TO A SLIGHT RISK FOR THIS AFTERNOON WITH DAMAGING WIND THE MAIN THREAT WITH MARGINAL SEVERE HAIL ALSO. STORMS WILL BE MOVING RATHER SLOWLY SO TORRENTIAL RAINS WILL ALSO BE A CONCERN AS PRECIPITABLE WATERS INCREASE TO OVER 1.50 INCHES. THERE WILL BE THE POTENTIAL FOR LOCALIZED FLASH FLOODING ESPECIALLY WHERE HEAVY RAINS HAVE FALLEN IN THE PAST WEEK. && .SYNOPSIS... ISSUED AT 249 AM CDT SUN JUN 22 2014 LATEST SFC ANALYSIS SHOWS SURFACE LOW OVER SOUTH CENTRAL NE WITH A WEAK STATIONARY FRONT STRETCHING ACROSS NORTHERN SECTIONS OF THE CWFA. DEW POINTS HOLDING IN THE 60S AND LIGHT WINDS IN THE FRONTAL ZONE SUPPORTING FOG DEVELOPMENT ALONG HWY 20 CORRIDOR IN PARTICULAR. ALOFT...NEAR ZONAL FLOW ACROSS THE CENTRAL US AT 500MB WITH WEAK RIDGING OVER THE UPPER MISSISSIPPI VALLEY. FESTERING WEAK CONVECTION VICINITY LSX AND MORE VIGOROUS STORMS OVER NW IA CURRENTLY HEADED EAST-SOUTHEASTWARD. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 249 AM CDT SUN JUN 22 2014 MAIN FORECAST CONCERN IN THE SHORT TERM IS POTENTIAL PRECIP TODAY. RECENT MODEL SOLUTIONS REGARDING PRECIPITATION HAVE BEEN LARGELY OVERDONE...THUS OVERALL CONFIDENCE IN SHORT TERM MODEL SOLUTIONS IS LOWER THAN NORMAL. ECMWF FOR EXAMPLE GROSSLY OVERFORECAST FORCING AND PRECIP YESTERDAY. THUS...FOR SHORT TERM WILL RELY ON BLEND OF THIS MORNINGS MORE CONSERVATIVE HRRR...NAM...AND RUC. STORMS CURRENTLY OVER NORTHWEST IA ARE HINTED AT BY HRRR AND RUC. BOTH AGREE WITH WEAKENING TREND AS THE CONVECTION COMES UP AGAINST THE UPPER RIDGE. GIVEN THIS EXPECTATION...THE MOST LIKELY OPPORTUNITY FOR RAIN LOCALLY WILL COME THIS AFTERNOON AS THE UPPER RIDGE SLIDES A BIT FARTHER EAST AND A SHORT WAVE PUSHES INTO WESTERN IA. CONVECTION SHOULD FIRE IN CENTRAL IA AND PUSH EAST INTO WESTERN SECTIONS OF THE CWFA THIS AFTERNOON. AS A RESULT...RAIN CHANCES HAVE BEEN LOWERED ACROSS THE BOARD FOR THIS MORNING AND SHIFTED A BIT WEST FOR THE AFTERNOON. PRECIP CHANCES WILL CONTINUE OVERNIGHT AS WEAK CYCLONIC FLOW AND A STRONGER SHORT WAVE OVERTAKE THE REGION. DMD .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 249 AM CDT SUN JUN 22 2014 MONDAY INTO MONDAY EVENING STILL ON TRACK FOR BEST PCPN CHCS IN NEXT FEW DAYS. MODELS CONTINUE TO DIVERGE ON WHETHER ANY PHASING OCCURS BETWEEN SOUTHERN CANADA SHORTWAVE AND ENERGY RIPPLING IN UNDERCUTTING QUASI-ZONAL FLOW... WITH MOST OF RECENT MODELS NOW SHOWING NO PHASING. PHASING WILL HAVE SIGNIFICANT IMPACTS ON PCPN AMOUNTS AND COVERAGE... AS MORE PHASED SCENARIO WOULD SUPPORT MCS WITH WIDESPREAD HEAVIER RAINS OF 1-3+ INCHES. BUT... ATTIM THE FCST IS TRENDING LOWER ON QPF AMOUNTS AND HARBORS SOME UNCERTAINTY ON PCPN COVERAGE MONDAY INTO MONDAY EVENING GIVEN LACK OF PHASING SUGGESTED BY MOST MODEL SOLUTIONS. THE CONCERN WITH NO PHASING IS THE POTENTIAL FOR SOME OF AREA TO BE SPLIT BY BETTER COVERAGE WITH ONE DISTURBANCE AND MORE CONCENTRATED BATCH OF CONVECTION LIFTING NORTHEASTWARD INTO UPPER MIDWEST AND AWAY FROM CWA... WHILE ANOTHER DISTURBANCE AND MORE ORGANIZED CONVECTION SHIFTS E/SE ACROSS PORTIONS OF SOUTH CENTRAL PLAINS DIVING INTO BEST INSTABILITY AND MOISTURE AXIS. WITH THAT BEING SAID... GIVEN HIGH PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES AND DECENT UPPER DIFFLUENCE WOULD ANTICIPATE STILL GOOD COVERAGE OF SHOWERS/STORMS ON MONDAY WITH RISK OF LOCALLY HEAVY RAIN. PCPN SHOULD TAPER OFF WEST TO EAST MONDAY EVENING WITH PASSAGE OF COLD FRONT. TUE-TUE NIGHT... SLIGHTLY COOLER AND DRIER CONDITIONS APPEAR ON TAP WITH WEAK SUBSIDENCE IN WAKE OF FRONT. WED-SAT... PATTERN SET TO RETURN UNSETTLED/ACTIVE WITH SEVERAL DISTURBANCES POSSIBLY IN QUASI-ZONAL FLOW BEFORE TRANSITION TO SOUTHWEST FLOW ALOFT LATE IN THE PERIOD AHEAD OF WESTERN CONUS TROUGH. SHOULD SEE A BIT OF AN UPTICK IN BOTH TEMPS AND HUMIDITY BY LATE WEEK AND ESPECIALLY NEXT WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 703 AM CDT SUN JUN 22 2014 A LARGE THUNDERSTORM COMPLEX OVER WESTERN IOWA IS EXPECTED TO CONTINUE TO WEAKEN AS IT MOVES INTO EASTERN IOWA. HOWEVER...ADDITIONAL SHOWERS AND STORMS SHOULD DEVELOP AHEAD OF THIS COMPLEX FROM MID DAY THROUGH THE AFTERNOON. THUS...THUNDERSTORMS ARE EXPECTED TO AFFECT AREA TAF SITES FROM EARLY AFTERNOON INTO THE EVENING...WITH MVFR AND POSSIBLY LOCAL IFR CONDITIONS. THUNDERSTORM CHANCES WILL CONTINUE THROUGH THE OVERNIGHT HOURS AND INTO MONDAY. DMD && .HYDROLOGY... ISSUED AT 249 AM CDT SUN JUN 22 2014 AREA TRIBUTARY RIVERS MAINLY NORTH OF I-80...AS WELL AS THE MAINSTEM MISSISSIPPI RIVER WILL CONTINUE TO RISE INTO NEXT WEEK IN RESPONSE TO RECENT HEAVY RAINFALL. THE POTENTIAL FOR LOCALLY HEAVY RAINFALL EXISTS NEXT 36-48 HRS...WITH BEST CHANCES FOR PCPN AND HEAVY RAINFALL LATE TONIGHT AND MONDAY. SOME GOOD NEWS THIS AM IN THAT WHAT WAS LOOKING LIKE POTENTIAL FOR WIDESPREAD SIGNIFICANT RAINFALL 1-3+ INCHES NOW MORE LOCALIZED POTENTIAL AS MODELS HAVE GENERALLY BACKED OFF TO A WEAKER STORM SYSTEM IMPACTING THE AREA. WOULD LIKE TO STRESS THAT WHILE THIS IS THE CASE THIS AM... THIS IS FAR FROM CERTAIN AND COULD CHANGE AS MODELS CONTINUALLY DIVERGING... THUS CAUTIOUS OPTIMISM THAT HIGHER QPF AMOUNTS MORE LOCALIZED AND NOT AS WIDESPREAD. RIVER SITES THAT ARE CURRENTLY UNDER A WARNING ARE FORECAST TO SEE MINOR TO MODERATE FLOODING...WITH THE EXCEPTION OF THE MISSISSIPPI RIVER AT BURLINGTON...WHERE MAJOR FLOODING IS FORECAST. HOWEVER...SHOULD A HEAVY SOAKING RAIN OF 1 TO 3+ INCHES OCCUR OVER ANY RIVER BASINS NEXT COUPLE OF DAYS...THEN RENEWED RISES AND HIGHER CREST LEVELS WOULD BE LIKELY. THOSE WITH INTERESTS ON AREA RIVERS OR WHO WOULD BE IMPACTED BY HIGH WATER LEVELS SHOULD PAY VERY CLOSE ATTENTION NEXT COUPLE OF DAYS. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...HAASE SYNOPSIS...DMD SHORT TERM...DMD LONG TERM...05 AVIATION...DMD HYDROLOGY...05
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
713 AM CDT SUN JUN 22 2014 .SYNOPSIS... ISSUED AT 249 AM CDT SUN JUN 22 2014 LATEST SFC ANALYSIS SHOWS SURFACE LOW OVER SOUTH CENTRAL NE WITH A WEAK STATIONARY FRONT STRETCHING ACROSS NORTHERN SECTIONS OF THE CWFA. DEW POINTS HOLDING IN THE 60S AND LIGHT WINDS IN THE FRONTAL ZONE SUPPORTING FOG DEVELOPMENT ALONG HWY 20 CORRIDOR IN PARTICULAR. ALOFT...NEAR ZONAL FLOW ACROSS THE CENTRAL US AT 500MB WITH WEAK RIDGING OVER THE UPPER MISSISSIPPI VALLEY. FESTERING WEAK CONVECTION VICINITY LSX AND MORE VIGOROUS STORMS OVER NW IA CURRENTLY HEADED EAST-SOUTHEASTWARD. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 249 AM CDT SUN JUN 22 2014 MAIN FORECAST CONCERN IN THE SHORT TERM IS POTENTIAL PRECIP TODAY. RECENT MODEL SOLUTIONS REGARDING PRECIPITATION HAVE BEEN LARGELY OVERDONE...THUS OVERALL CONFIDENCE IN SHORT TERM MODEL SOLUTIONS IS LOWER THAN NORMAL. ECMWF FOR EXAMPLE GROSSLY OVERFORECAST FORCING AND PRECIP YESTERDAY. THUS...FOR SHORT TERM WILL RELY ON BLEND OF THIS MORNINGS MORE CONSERVATIVE HRRR...NAM...AND RUC. STORMS CURRENTLY OVER NORTHWEST IA ARE HINTED AT BY HRRR AND RUC. BOTH AGREE WITH WEAKENING TREND AS THE CONVECTION COMES UP AGAINST THE UPPER RIDGE. GIVEN THIS EXPECTATION...THE MOST LIKELY OPPORTUNITY FOR RAIN LOCALLY WILL COME THIS AFTERNOON AS THE UPPER RIDGE SLIDES A BIT FARTHER EAST AND A SHORT WAVE PUSHES INTO WESTERN IA. CONVECTION SHOULD FIRE IN CENTRAL IA AND PUSH EAST INTO WESTERN SECTIONS OF THE CWFA THIS AFTERNOON. AS A RESULT...RAIN CHANCES HAVE BEEN LOWERED ACROSS THE BOARD FOR THIS MORNING AND SHIFTED A BIT WEST FOR THE AFTERNOON. PRECIP CHANCES WILL CONTINUE OVERNIGHT AS WEAK CYCLONIC FLOW AND A STRONGER SHORT WAVE OVERTAKE THE REGION. DMD .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 249 AM CDT SUN JUN 22 2014 MONDAY INTO MONDAY EVENING STILL ON TRACK FOR BEST PCPN CHCS IN NEXT FEW DAYS. MODELS CONTINUE TO DIVERGE ON WHETHER ANY PHASING OCCURS BETWEEN SOUTHERN CANADA SHORTWAVE AND ENERGY RIPPLING IN UNDERCUTTING QUASI-ZONAL FLOW... WITH MOST OF RECENT MODELS NOW SHOWING NO PHASING. PHASING WILL HAVE SIGNIFICANT IMPACTS ON PCPN AMOUNTS AND COVERAGE... AS MORE PHASED SCENARIO WOULD SUPPORT MCS WITH WIDESPREAD HEAVIER RAINS OF 1-3+ INCHES. BUT... ATTIM THE FCST IS TRENDING LOWER ON QPF AMOUNTS AND HARBORS SOME UNCERTAINTY ON PCPN COVERAGE MONDAY INTO MONDAY EVENING GIVEN LACK OF PHASING SUGGESTED BY MOST MODEL SOLUTIONS. THE CONCERN WITH NO PHASING IS THE POTENTIAL FOR SOME OF AREA TO BE SPLIT BY BETTER COVERAGE WITH ONE DISTURBANCE AND MORE CONCENTRATED BATCH OF CONVECTION LIFTING NORTHEASTWARD INTO UPPER MIDWEST AND AWAY FROM CWA... WHILE ANOTHER DISTURBANCE AND MORE ORGANIZED CONVECTION SHIFTS E/SE ACROSS PORTIONS OF SOUTH CENTRAL PLAINS DIVING INTO BEST INSTABILITY AND MOISTURE AXIS. WITH THAT BEING SAID... GIVEN HIGH PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES AND DECENT UPPER DIFFLUENCE WOULD ANTICIPATE STILL GOOD COVERAGE OF SHOWERS/STORMS ON MONDAY WITH RISK OF LOCALLY HEAVY RAIN. PCPN SHOULD TAPER OFF WEST TO EAST MONDAY EVENING WITH PASSAGE OF COLD FRONT. TUE-TUE NIGHT... SLIGHTLY COOLER AND DRIER CONDITIONS APPEAR ON TAP WITH WEAK SUBSIDENCE IN WAKE OF FRONT. WED-SAT... PATTERN SET TO RETURN UNSETTLED/ACTIVE WITH SEVERAL DISTURBANCES POSSIBLY IN QUASI-ZONAL FLOW BEFORE TRANSITION TO SOUTHWEST FLOW ALOFT LATE IN THE PERIOD AHEAD OF WESTERN CONUS TROUGH. SHOULD SEE A BIT OF AN UPTICK IN BOTH TEMPS AND HUMIDITY BY LATE WEEK AND ESPECIALLY NEXT WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 703 AM CDT SUN JUN 22 2014 A LARGE THUNDERSTORM COMPLEX OVER WESTERN IOWA IS EXPECTED TO CONTINUE TO WEAKEN AS IT MOVES INTO EASTERN IOWA. HOWEVER...ADDITIONAL SHOWERS AND STORMS SHOULD DEVELOP AHEAD OF THIS COMPLEX FROM MID DAY THROUGH THE AFTERNOON. THUS...THUNDERSTORMS ARE EXPECTED TO AFFECT AREA TAF SITES FROM EARLY AFTERNOON INTO THE EVENING...WITH MVFR AND POSSIBLY LOCAL IFR CONDITIONS. THUNDERSTORM CHANCES WILL CONTINUE THROUGH THE OVERNIGHT HOURS AND INTO MONDAY. DMD && .HYDROLOGY... ISSUED AT 249 AM CDT SUN JUN 22 2014 AREA TRIBUTARY RIVERS MAINLY NORTH OF I-80...AS WELL AS THE MAINSTEM MISSISSIPPI RIVER WILL CONTINUE TO RISE INTO NEXT WEEK IN RESPONSE TO RECENT HEAVY RAINFALL. THE POTENTIAL FOR LOCALLY HEAVY RAINFALL EXISTS NEXT 36-48 HRS...WITH BEST CHANCES FOR PCPN AND HEAVY RAINFALL LATE TONIGHT AND MONDAY. SOME GOOD NEWS THIS AM IN THAT WHAT WAS LOOKING LIKE POTENTIAL FOR WIDESPREAD SIGNIFICANT RAINFALL 1-3+ INCHES NOW MORE LOCALIZED POTENTIAL AS MODELS HAVE GENERALLY BACKED OFF TO A WEAKER STORM SYSTEM IMPACTING THE AREA. WOULD LIKE TO STRESS THAT WHILE THIS IS THE CASE THIS AM... THIS IS FAR FROM CERTAIN AND COULD CHANGE AS MODELS CONTINUALLY DIVERGING... THUS CAUTIOUS OPTIMISM THAT HIGHER QPF AMOUNTS MORE LOCALIZED AND NOT AS WIDESPREAD. RIVER SITES THAT ARE CURRENTLY UNDER A WARNING ARE FORECAST TO SEE MINOR TO MODERATE FLOODING...WITH THE EXCEPTION OF THE MISSISSIPPI RIVER AT BURLINGTON...WHERE MAJOR FLOODING IS FORECAST. HOWEVER...SHOULD A HEAVY SOAKING RAIN OF 1 TO 3+ INCHES OCCUR OVER ANY RIVER BASINS NEXT COUPLE OF DAYS...THEN RENEWED RISES AND HIGHER CREST LEVELS WOULD BE LIKELY. THOSE WITH INTERESTS ON AREA RIVERS OR WHO WOULD BE IMPACTED BY HIGH WATER LEVELS SHOULD PAY VERY CLOSE ATTENTION NEXT COUPLE OF DAYS. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...DMD SHORT TERM...DMD LONG TERM...05 AVIATION...DMD HYDROLOGY...05
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
338 AM CDT SUN JUN 22 2014 .SYNOPSIS... ISSUED AT 249 AM CDT SUN JUN 22 2014 LATEST SFC ANALYSIS SHOWS SURFACE LOW OVER SOUTH CENTRAL NE WITH A WEAK STATIONARY FRONT STRETCHING ACROSS NORTHERN SECTIONS OF THE CWFA. DEW POINTS HOLDING IN THE 60S AND LIGHT WINDS IN THE FRONTAL ZONE SUPPORTING FOG DEVELOPMENT ALONG HWY 20 CORRIDOR IN PARTICULAR. ALOFT...NEAR ZONAL FLOW ACROSS THE CENTRAL US AT 500MB WITH WEAK RIDGING OVER THE UPPER MISSISSIPPI VALLEY. FESTERING WEAK CONVECTION VICINITY LSX AND MORE VIGOROUS STORMS OVER NW IA CURRENTLY HEADED EAST-SOUTHEASTWARD. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 249 AM CDT SUN JUN 22 2014 MAIN FORECAST CONCERN IN THE SHORT TERM IS POTENTIAL PRECIP TODAY. RECENT MODEL SOLUTIONS REGARDING PRECIPITATION HAVE BEEN LARGELY OVERDONE...THUS OVERALL CONFIDENCE IN SHORT TERM MODEL SOLUTIONS IS LOWER THAN NORMAL. ECMWF FOR EXAMPLE GROSSLY OVERFORECAST FORCING AND PRECIP YESTERDAY. THUS...FOR SHORT TERM WILL RELY ON BLEND OF THIS MORNINGS MORE CONSERVATIVE HRRR...NAM...AND RUC. STORMS CURRENTLY OVER NORTHWEST IA ARE HINTED AT BY HRRR AND RUC. BOTH AGREE WITH WEAKENING TREND AS THE CONVECTION COMES UP AGAINST THE UPPER RIDGE. GIVEN THIS EXPECTATION...THE MOST LIKELY OPPORTUNITY FOR RAIN LOCALLY WILL COME THIS AFTERNOON AS THE UPPER RIDGE SLIDES A BIT FARTHER EAST AND A SHORT WAVE PUSHES INTO WESTERN IA. CONVECTION SHOULD FIRE IN CENTRAL IA AND PUSH EAST INTO WESTERN SECTIONS OF THE CWFA THIS AFTERNOON. AS A RESULT...RAIN CHANCES HAVE BEEN LOWERED ACROSS THE BOARD FOR THIS MORNING AND SHIFTED A BIT WEST FOR THE AFTERNOON. PRECIP CHANCES WILL CONTINUE OVERNIGHT AS WEAK CYCLONIC FLOW AND A STRONGER SHORT WAVE OVERTAKE THE REGION. DMD .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 249 AM CDT SUN JUN 22 2014 MONDAY INTO MONDAY EVENING STILL ON TRACK FOR BEST PCPN CHCS IN NEXT FEW DAYS. MODELS CONTINUE TO DIVERGE ON WHETHER ANY PHASING OCCURS BETWEEN SOUTHERN CANADA SHORTWAVE AND ENERGY RIPPLING IN UNDERCUTTING QUASI-ZONAL FLOW... WITH MOST OF RECENT MODELS NOW SHOWING NO PHASING. PHASING WILL HAVE SIGNIFICANT IMPACTS ON PCPN AMOUNTS AND COVERAGE... AS MORE PHASED SCENARIO WOULD SUPPORT MCS WITH WIDESPREAD HEAVIER RAINS OF 1-3+ INCHES. BUT... ATTIM THE FCST IS TRENDING LOWER ON QPF AMOUNTS AND HARBORS SOME UNCERTAINTY ON PCPN COVERAGE MONDAY INTO MONDAY EVENING GIVEN LACK OF PHASING SUGGESTED BY MOST MODEL SOLUTIONS. THE CONCERN WITH NO PHASING IS THE POTENTIAL FOR SOME OF AREA TO BE SPLIT BY BETTER COVERAGE WITH ONE DISTURBANCE AND MORE CONCENTRATED BATCH OF CONVECTION LIFTING NORTHEASTWARD INTO UPPER MIDWEST AND AWAY FROM CWA... WHILE ANOTHER DISTURBANCE AND MORE ORGANIZED CONVECTION SHIFTS E/SE ACROSS PORTIONS OF SOUTH CENTRAL PLAINS DIVING INTO BEST INSTABILITY AND MOISTURE AXIS. WITH THAT BEING SAID... GIVEN HIGH PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES AND DECENT UPPER DIFFLUENCE WOULD ANTICIPATE STILL GOOD COVERAGE OF SHOWERS/STORMS ON MONDAY WITH RISK OF LOCALLY HEAVY RAIN. PCPN SHOULD TAPER OFF WEST TO EAST MONDAY EVENING WITH PASSAGE OF COLD FRONT. TUE-TUE NGT... SLIGHTLY COOLER AND DRIER CONDITIONS APPEAR ON TAP WITH WEAK SUBSIDENCE IN WAKE OF FRONT. WED-SAT... PATTERN SET TO RETURN UNSETTLED/ACTIVE WITH SEVERAL DISTURBANCES POSSIBLY IN QUASI-ZONAL FLOW BEFORE TRANSITION TO SOUTHWEST FLOW ALOFT LATE IN THE PERIOD AHEAD OF WESTERN CONUS TROUGH. SHOULD SEE A BIT OF AN UPTICK IN BOTH TEMPS AND HUMIDITY BY LATE WEEK AND ESPECIALLY NEXT WEEKEND. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1159 PM CDT SAT JUN 21 2014 LIGHT WINDS AND RECENT RAINFALL MAY RESULT IN SOME MVFR FOG OVERNIGHT. CONVECTIVE TRENDS ARE STILL VERY MUCH IN QUESTION FOR SUNDAY AND SUNDAY NIGHT...BUT TRENDS FAVOR THE BULK OF THE THUNDERSTORM ACTIVITY SUNDAY EVENING. HAVE OPTED FOR VCTS GROUPS AT KBRL/KCID/KMLI AT 00Z. && .HYDROLOGY... ISSUED AT 249 AM CDT SUN JUN 22 2014 AREA TRIBUTARY RIVERS MAINLY NORTH OF I-80...AS WELL AS THE MAINSTEM MISSISSIPPI RIVER WILL CONTINUE TO RISE INTO NEXT WEEK IN RESPONSE TO RECENT HEAVY RAINFALL. THE POTENTIAL FOR LOCALLY HEAVY RAINFALL EXISTS NEXT 36-48 HRS...WITH BEST CHANCES FOR PCPN AND HEAVY RAINFALL LATE TONIGHT AND MONDAY. SOME GOOD NEWS THIS AM IN THAT WHAT WAS LOOKING LIKE POTENTIAL FOR WIDESPREAD SIGNIFICANT RAINFALL 1-3+ INCHES NOW MORE LOCALIZED POTENTIAL AS MODELS HAVE GENERALLY BACKED OFF TO A WEAKER STORM SYSTEM IMPACTING THE AREA. WOULD LIKE TO STRESS THAT WHILE THIS IS THE CASE THIS AM... THIS IS FAR FROM CERTAIN AND COULD CHANGE AS MODELS CONTINUALLY DIVERGING... THUS CAUTIOUS OPTIMISM THAT HIGHER QPF AMOUNTS MORE LOCALIZED AND NOT AS WIDESPREAD. RIVER SITES THAT ARE CURRENTLY UNDER A WARNING ARE FORECAST TO SEE MINOR TO MODERATE FLOODING...WITH THE EXCEPTION OF THE MISSISSIPPI RIVER AT BURLINGTON...WHERE MAJOR FLOODING IS FORECAST. HOWEVER...SHOULD A HEAVY SOAKING RAIN OF 1 TO 3+ INCHES OCCUR OVER ANY RIVER BASINS NEXT COUPLE OF DAYS...THEN RENEWED RISES AND HIGHER CREST LEVELS WOULD BE LIKELY. THOSE WITH INTERESTS ON AREA RIVERS OR WHO WOULD BE IMPACTED BY HIGH WATER LEVELS SHOULD PAY VERY CLOSE ATTENTION NEXT COUPLE OF DAYS. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...DMD SHORT TERM...DMD LONG TERM...05 AVIATION...RP KINNEY HYDROLOGY...05
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1209 AM CDT SUN JUN 22 2014 .UPDATE... ISSUED AT 916 PM CDT SAT JUN 21 2014 LITTLE CHANGE FROM PREVIOUS THINKING THIS EVENING. LARGE SCALE FORCING AHEAD OF APPROACHING CO/WY SHORT WAVES WILL KEEP SCATTERED CONVECTION GOING IN SOME FORM UPSTREAM OVERNIGHT. SD MCS IS MOST PRESSING CONCERN BUT SEVERE WEATHER POTENTIAL SEEMS LOW. ALTHOUGH A FEW CELLS HAVE ACCELERATED FASTER FOR THE MOMENT...COMPLEX IS CURRENTLY FOLLOWING CORFIDI VECTORS AS A WHOLE AND DRIFTING SE AT 15-20KTS. EXPECT THIS COMPLEX TO WEAKEN SOMEWHAT WITH DECREASE/INCREASE IN MLCAPE/CINH RESPECTIVELY INTO THE NIGHT AND JUST WEAK TO MODERATE EFFECTIVE SHEAR. HEAVY RAIN IS MORE OF A CONCERN THAN SEVERE WITH ELEVATED K INDEX/PW AXIS DRIFTING EWD INTO WRN IA COINCIDENT WITH LOW LEVEL MOISTURE FLUX AS IT MOVES EWD WITH OVERALL SYSTEM AND VEERS. 01Z RAP CORFIDI VECTORS/MEAN WIND ARE BOTH 15KTS OR LESS BY 09Z SO WHAT IS LEFT OF THE COMPLEX WILL LIKELY BE SLOW MOVING. AIRMASS WILL SUPPORT EFFICIENT RAINFALL RATES BUT PWS AND WARM CLOUD DEPTHS ARE NOT AS EXTREME AS RECENT EVENTS. && .SHORT TERM /TONIGHT/... ISSUED AT 320 PM CDT SAT JUN 21 2014 CONVECTIVE TRENDS OVERNIGHT ARE THE PRIMARY FORECAST CHALLENGE OVERNIGHT. MCV SHIFTING EAST ACROSS SRN WISCONSIN AND NRN ILLINOIS HAS WRAPPED DRY MID LEVEL AIR IN TO CENTRAL AND EASTERN IOWA. THIS HAS HELPED STRENGTHEN THE CONVECTIVE INHIBITION ACROSS THE AREA. SFC FLOW OVER CENTRAL IOWA REMAINS NEARLY NON EXISTENT WITH THE OVERNIGHT OUTFLOW PUSHING THE WARM FRONT JUST SOUTH INTO KANSAS AND MISSOURI. A FEW STORMS HAVE BEEN TRYING TO INITIATE ALONG THIS BOUNDARY BUT HAVING A DIFFICULT TIME BECOMING ORGANIZED WITH A LACK OF DEEP LAYER SHEAR AND ANY GOOD FORCING TO AID IN SUSTAINING UPDRAFTS. THIS ACTIVITY SHOULD MOSTLY REMAIN SOUTH OF THE STATE BUT MAY CLIP THE SOUTHERN TIER OF COUNTIES THE NEXT FEW HOURS. FORCING REMAINS WEAK ACROSS CENTRAL IOWA THROUGH THIS EVENING. THE LOW LEVEL JET OF AROUND 35 KTS WILL AMPLIFY OVER THE MID MISSOURI VALLEY AND POINTS TO THE WEST HOWEVER ITS ORIENTATION WILL FAVOR THE FORCING AND CONVERGENCE ZONE ACROSS NEBRASKA AND SOUTH DAKOTA. A SHORT WAVE MOVING RAPIDLY ACROSS THE ROCKIES OVERNIGHT SHOULD SPREAD QG FORCING EAST INTO WESTERN IOWA LATE AND WILL HAVE PUSH ANY DEVELOPING MCS CLOSE TO THE STATE LATE. POSSIBLE A FEW STORMS DEVELOP OVER THE CENTRAL AND SOUTHWEST AS A COUPLE WAVES OF THETA-E ADVECTION LIFT NORTH AND GENERATE AN INSTABILITY AXIS THROUGH THAT REGION. A DISCONTINUITY BETWEEN FORCING AND MOISTURE AVAILABLE SHOULD PREVENT WIDESPREAD ACTIVITY AHEAD OF THE WESTERN MCS. THE THREAT FOR SEVERE WEATHER IS LOW THROUGH THE PERIOD THOUGH CAN NOT DISCOUNT A LOCALIZED EVENT. THE THREAT FOR HEAVY RAIN IS ALSO LOW THROUGH 12Z. .LONG TERM /SUNDAY THROUGH SATURDAY/... ISSUED AT 320 PM CDT SAT JUN 21 2014 MAIN CONCERNS CONTINUE TO FOCUS ON POTENTIAL FOR HEAVY RAINFALL WITH NEXT UPSTREAM WAVE EXPECTED TO CROSS THE REGION SUNDAY INTO EARLY MONDAY. EXPECTING SOME LEFTOVER CONVECTION ONCE AGAIN EARLY SUNDAY MORNING TO DECAY DURING THE MORNING HOURS ACROSS THE NORTH. A SLIGHTLY WEAKER WAVE IS NOW EXPECTED CROSS THE REGION INTO MONDAY. PREVIOUS MODEL SOLUTIONS SUGGESTED A STRONGER WAVE TRACKING OVER SOUTHERN IOWA/NORTHERN MISSOURI BUT LAST 2 RUNS OF THE MODELS SHOW SOMEWHAT OF A SPLIT NORTHERN/SOUTHERN STREAM WAVE CROSSING THE REGION. THIS SHOULD RESULT IN A LESSER THREAT FOR WIDESPREAD HEAVY RAIN ACROSS THE SOUTHEAST TWO THIRDS OF THE AREA FOR SUNDAY THROUGH MONDAY...BUT INCREASE THE RISK OF RAINFALL AND SOME LOCALLY HEAVY RAIN OVER THE NORTHERN AREAS OF THE FORECAST AREA. BOTH THE 12Z GFS/NAM ARE NOW FAVORING THE NORTHERN STREAM ENERGY TO DOMINATE THE NEXT 24 TO 36 HOURS...WITH WARM AIR ADVECTION AND FRONTAL FORCING MAXIMIZED FROM NORTHWEST IOWA THROUGH SOUTHEAST MINNESOTA AND A SECONDARY WAVE WELL SOUTH OF THE AREA. THIS LEAVES THE BULK OF CENTRAL IOWA IN AN AREA OF LESS FAVORABLE CONVERGENCE AND FORCING. TODAYS 12Z GEM MODEL HAS ALSO SPLIT THE ENERGY IN A SIMILAR PATTERN...WITH SYNOPTIC DEVELOPMENT OF THE WAVES OVER NORTHERN IOWA AND IN THE SOUTHERN PLAINS. THIS WOULD FAVOR TWO AREAS OF HEAVIER RAINFALL...ONE OVER NORTHERN IOWA AND THE OTHER OVER MISSOURI SOUTH TO NEAR THE OKLAHOMA/ARKANSAS BORDER. WITH THE SUGGESTION OF SPLIT FLOW...THE PATTERN WOULD BE MORE PROGRESSIVE WITH A QUICKER EXIT OF THE FRONT BY LATE MONDAY MORNING RATHER THAN MONDAY NIGHT. OVERALL THIS SHOULD HELP LIMIT WIDESPREAD HEAVY RAINFALL. HOWEVER...WE CONTINUE HAVE HIGH PRECIPITABLE WATER VALUES OF 1.5 TO 1.75 WITH WARM CLOUD DEPTHS ONCE AGAIN RUNNING FROM 11500 TO 13000 FT. THERE MAY STILL BE LOCALLY HEAVY RAINFALL NEARER THE SFC LOW AS IT TRACKS ACROSS CENTRAL TO NORTHERN IOWA WITH MORE WIDELY SCATTERED POCKETS OF LOCALLY HEAVY RAINFALL IN THE CENTRAL AND SOUTH MAINLY DURING THE AFTERNOON AND EVENING HOURS. HIGHS SUNDAY WILL BE VERY WARM...BUT WITH CLOUD COVER AROUND PROBABLY HELD INTO THE LOWER TO MID 80S WITH A FEW UPPER 80S IN THE SOUTH. COOLER WEATHER WILL RETURN TOWARD MONDAY AND TUESDAY AS THE SYSTEM PULLS EAST. TUESDAY MORNING EITHER LOOKS TO BE A GREAT CANDIDATE FOR FOG OR A LOT OF DEW. WILL NEED TO TAKE A LOOK AT THIS IN THE NEXT PACKAGE OR TWO AS WINDS BECOME VERY LIGHT BY THAT TIME AND TEMPERATURES RADIATE BACK INTO THE LOWER 60S. THERE REMAINS A WEAK SIGNAL FOR SOME SHOWERS TUESDAY OR WEDNESDAY OVER THE NORTH AND WEDNESDAY OVER THE CENTRAL. FOR NOW...GREATER UNCERTAINTY ABOUT CHANCES FOR RETURN MOISTURE THAT SOON...AND THIS MAY CHANGE. BY MID TO LATE IN THE PERIOD A WEST SOUTHWEST FLOW WILL RETURN ALOFT. THIS WILL PROMOTE WARMER TEMPERATURES AND INCREASED CHANCES FOR THUNDERSTORMS. HIGHS THROUGH MIDWEEK WILL REMAIN IN THE LOWER 80S WITH LOWS IN THE 60S. BY LATE IN THE PERIOD MID 80S ARE MORE LIKELY WITH LOWS IN THE UPPER 60S TO LOWER 70S. AS TEMPS WARM ALOFT AT H700 TO ABOVE 10C...THUNDERSTORM CHANCES MAY BE CAPPED BUT UNCERTAINTY INCREASES TOWARD THE END OF THE EXTENDED FORECAST. && .AVIATION...22/06Z ISSUED AT 1209 AM CDT SUN JUN 22 2014 VFR CONDITIONS ARE ANTICIPATED INTO SUN MORNING WITH ATTENTION TURNING UPSTREAM INTO SD FOR CONVECTIVE TRENDS. SHOWERS AND STORMS ARE POSSIBLE FOR A PERIOD BEFORE DAYBREAK...WITH BETTER LIKELIHOOD NW VS SE. RESTRICTIONS ARE POSSIBLE WITH HEAVIER RAIN SHOWERS BUT LIKELIHOOD AT ANY PARTICULAR TAF SITES IS QUITE LOW. SURFACE BASED CONVECTION IS ALSO POSSIBLE LATER IN THE DAY. HAVE FAIRLY HIGH CONFIDENCE IN PRECIP SOMETIME SUN MIDDAY INTO THE EVENING...BUT TIMING AND LOCATIONS HAVE LITTLE PREDICTABILITY AT THIS POINT SO HAVE NOTHING MORE THAN PROLONGED VFR VCSH WORDING FOR NOW. && .HYDROLOGY... ISSUED AT 320 PM CDT SAT JUN 21 2014 TONIGHT THROUGH MONDAY NIGHT THE MAIN CONCERN LATE TONIGHT AND EARLY SUNDAY WILL BE MCS DEVELOPMENT OVER THE WESTERN PLAINS...MOVING EAST INTO NORTHWEST IOWA BY MORNING. THIS ACTIVITY SHOULD DECAY EARLY IN THE DAY BUT AS THE MAIN SHORTWAVE MOVES ACROSS THE AREA SUNDAY...THUNDERSTORMS WILL INCREASE IN COVERAGE. WITH PWATS CONTINUING HIGH AND WARM CLOUD DEPTHS FAVORING EFFICIENT RAINFALL PROCESSES...SOME AMOUNTS OF 1 TO 2 INCHES IN A SHORT PERIOD OF TIME WILL BE POSSIBLE SUNDAY INTO SUNDAY EVENING ESPECIALLY. MOST 1 AND 3 HOUR GRIDDED FLASH FLOOD GUIDANCE OVER THE REGION IS ABOUT 1 TO 2 INCHES...SO IF ANY STORMS WITH HIGH RAINFALL RATES DEVELOP...THERE WILL BE A POTENTIAL FOR SOME LOCALIZED FLOODING ISSUES. ONE LIMITING FACTOR SUNDAY WILL BE A SLIGHTLY MORE PROGRESSIVE WAVE AS THE MAIN SHORTWAVE TRACKS EAST. CONFIDENCE OF OVERALL COVERAGE AND LOCATION IS LOW ENOUGH TO LEAVE HEADLINES OUT FOR NOW. RIVER LEVELS WILL RESPOND AGAIN TO ANY ADDITIONAL RAINFALL OVER OUR FORECAST AREA SUNDAY AND SUNDAY EVENING. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SMALL SHORT TERM...DONAVON LONG TERM...REV AVIATION...SMALL HYDROLOGY...REV
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
755 PM CDT Mon Jun 23 2014 ...updated aviation section... .SHORT TERM...(This evening through Tuesday) ISSUED AT 300 PM CDT MON JUN 23 2014 Another MCS night likely across far western Kansas. There is isolated weak thunderstorms developing across south central Kansas this afternoon as well. Have the highest pops along and west of Garden City to Liberal, although the most recent HRRR propagates the MCS farther east. Something to watch and update ESTF grids based on reality rather than model output solutions. There could be some severe weather across far western Kansas as meso analyzed SBCAPES are near 2000 J/kg and 30 kt effective bulk shear. Most probable threat is hail and winds along with heavy rainfall as pwats remain just below the 75th percentile for a normal distribution. Overnight minimums will be in the 60sF. Another MCS likely tomorrow. Attempted to add some diurnal pop variability with a minimum towards 18Z and maximum at the end of my period. Some uncertainty in storm placement as convective allowing models are different than the global models. Broad bushed pops at this point as pwats remain high and the overall synoptic pattern is that which is conducive for MCS`s. There could be some marginal severe weather again as instability is moderate and bulk shear is more marginal. Highs in the 80sF. .LONG TERM...(Tuesday night through Monday) ISSUED AT 344 PM CDT MON JUN 23 2014 For Tuesday night, a weak upper level shortwave trough will be moving across western Kansas with numerous showers and thunderstorms expected as an MCS. At this time with weak wind shear and instability the chances for severe do not look that promising. Have upped precip chances. Overnight lows will be in the mid 60s. On Wednesday, more widely scattered thunderstorms are possible with moderate instability mainly by late afternoon. The upper level winds again look weak with severe thunderstorms not a good bet. Highs will be in the mid to upper 80s. For the period Thursday into next Monday, the best chance for more scattered thunderstorms looks to be on Thursday with another weak upper level wave. A stronger wave moves from the Pacific Northwest and into the Northern Plains by the Weekend with the best chance for thunderstorms mainly far north across I-70. Lows will be mild in the upper 60s to lower 70s, with highs warming slowly from the upper 80s into the low to mid 90s by the Weekend. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) ISSUED AT 721 PM CDT MON JUN 23 2014 && .PRELIMINARY POINT TEMPS/POPS... DDC 63 85 65 87 / 60 40 50 30 GCK 62 85 64 87 / 60 40 50 20 EHA 62 84 64 89 / 60 40 50 30 LBL 63 87 64 88 / 60 40 50 30 HYS 63 82 64 85 / 30 20 40 30 P28 65 86 68 86 / 10 30 40 40 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Sugden LONG TERM...Kruse AVIATION...Russell
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1259 PM MDT SUN JUN 22 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 1230 PM MDT SUN JUN 22 2014 THUNDERSTORM ACTIVITY EXPECTED TO RAMP UP QUICKLY AFTER 3 PM MDT (4 PM CDT) AS A WEATHER DISTURBANCE IGNITES A FEW STORMS IN FAR EASTERN COLORADO. AS THE DISTURBANCE MOVES EAST A LINE OF STRONG TO SEVERE THUNDERSTORMS IS EXPECTED PRODUCING LARGE HAIL...DAMAGING WINDS AND LOCALLY HEAVY RAINFALL. THE HRRR HAS BEEN SLOWLY INCREASING THE WIND GUST POTENTIAL WITH THE LINE AND WE COULD EXPERIENCE ANOTHER EPISODE OF 70+ MPH GUSTS. LOWS TONIGHT IN THE MID 50S WEST...MID 60S EAST. ON MONDAY MAY SEE SHOWERS AND THUNDERSTORMS IN THE LATE AFTERNOON HOURS...PRIMARILY ACROSS FAR EASTERN COLORADO. OTHERWISE EXPECT SOME CLOUDINESS WITH HIGHS IN THE MID 70S TO LOW 80S. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 1242 PM MDT SUN JUN 22 2014 A FEW STORMS IN SOUTHEAST COLORADO MONDAY EVENING MAY SNEAK INTO SOUTHWESTERN PARTS OF THE AREA...BUT BETTER CHANCES WILL BE AFTER MIDNIGHT AS LLJ STRENGTHENS AND SHORTWAVE TROUGH COMES OUT OF THE NORTHERN ROCKIES. STORMS MAY BE SLIGHTLY ELEVATED OVERNIGHT...WITH PARCELS ORIGINATING AROUND 800MB HAVING UP TO 1000 J/KG OF ELEVATED CAPE AND LITTLE TO NO CIN. LARGE HAIL WILL BE POSSIBLE OVERNIGHT WITH THESE STORMS. SOME OF THIS ACTIVITY WILL LINGER INTO TUESDAY MORNING...PARTICULARLY IN SOUTHWEST NEBRASKA...BEFORE AFTERNOON CONVECTION GETS GOING IN NORTHEAST COLORADO WITH THE NEXT SHORTWAVE. MODERATE INSTABILITY COMBINED WITH DEEP LAYER SHEAR OF 30-40KTS SUGGEST ANOTHER ROUND OF SEVERE STORMS AS THEY SLIDE ACROSS THE AREA TUESDAY EVENING. SOUTHEASTERLY SURFACE WINDS CONTINUE ON WEDNESDAY WITH A CORRIDOR OF VERY UNSTABLE CONDITIONS FORECAST BY THE AFTERNOON IN THE WESTERN HALF OF THE FORECAST AREA. DEEP LAYER SHEAR HOWEVER IS SOMEWHAT WEAKER AT AROUND 30KTS...BUT SHOULD BE ADEQUATE FOR SEVERE STORMS AS NEXT SHORTWAVE COMES OUT OF NORTHERN COLORADO IN THE AFTERNOON/EVENING. A SUBTLE PATTERN CHANGE OCCURS IN THE LAST HALF OF THE LONG TERM PERIOD WITH LONGWAVE TROUGH SETTLING INTO THE NORTHERN ROCKIES. THE UPPER FLOW OVER THE CENTRAL PLAINS WILL BECOME SOUTHWEST. SHORTWAVE TROUGHS ROTATING AROUND THE ROCKIES TROUGH OR EVEN THE RIDGE OVER THE CENTRAL GULF WILL PROVIDE ENOUGH LIFT TO CONTINUE THE MENTION OF DAILY THUNDERSTORM CHANCES. TEMPERATURES WILL BE NEAR TO SLIGHTLY ABOVE NORMAL THROUGH THE LONG TERM. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1120 AM MDT SUN JUN 22 2014 KGLD...VFR CONDITIONS EXPECTED THROUGH 00Z WITH NORTHEAST WINDS AROUND 10KTS. IN THE 00Z-03Z TIME FRAME CURRENT INDICATIONS ARE FOR A LINE OF STRONG TO SEVERE THUNDERSTORMS TO IMPACT THE TERMINAL WITH WIND GUSTS OVER 45 KTS POSSIBLE ALONG WITH LARGE HAIL AND HEAVY RAINFALL CREATING MVFR CONDITIONS. AFTER 03Z NORTHEAST WINDS GUSTING 15-20KTS WILL DECREASE TO 10KTS OR LESS FROM THE NORTH/NORTHEAST. KMCK...VFR CONDITIONS EXPECTED THROUGH 01Z WITH NORTHEAST WINDS AROUND 10KTS INCREASING AND GUSTING NEAR 20KTS AFTER 22Z. FROM 02Z-05Z CURRENT INDICATIONS ARE FOR A LINE OF STRONG TO SEVERE THUNDERSTORMS TO POSSIBLY IMPACT THE TERMINAL WITH WIND GUSTS TO 35KTS...POSSIBLY SOME SMALL HAIL AND HEAVY RAINFALL CREATING MVFR CONDITIONS. THE STRONGER STORMS AND WINDS ARE CURRENTLY EXPECTED TO BE SOUTH OF THE TERMINAL. AFTER 05Z NORTH TO NORTHEAST WINDS UNDER 10KTS EXPECTED. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...99 LONG TERM...024 AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1230 PM MDT SUN JUN 22 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 1230 PM MDT SUN JUN 22 2014 THUNDERSTORM ACTIVITY EXPECTED TO RAMP UP QUICKLY AFTER 3 PM MDT (4 PM CDT) AS A WEATHER DISTURBANCE IGNITES A FEW STORMS IN FAR EASTERN COLORADO. AS THE DISTURBANCE MOVES EAST A LINE OF STRONG TO SEVERE THUNDERSTORMS IS EXPECTED PRODUCING LARGE HAIL...DAMAGING WINDS AND LOCALLY HEAVY RAINFALL. THE HRRR HAS BEEN SLOWLY INCREASING THE WIND GUST POTENTIAL WITH THE LINE AND WE COULD EXPERIENCE ANOTHER EPISODE OF 70+ MPH GUSTS. LOWS TONIGHT IN THE MID 50S WEST...MID 60S EAST. ON MONDAY MAY SEE SHOWERS AND THUNDERSTORMS IN THE LATE AFTERNOON HOURS...PRIMARILY ACROSS FAR EASTERN COLORADO. OTHERWISE EXPECT SOME CLOUDINESS WITH HIGHS IN THE MID 70S TO LOW 80S. .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 255 AM MDT SUN JUN 22 2014 MODELS ARE STILL SHOWING A VERY ACTIVE WEATHER PATTERN OVER THE CWA THROUGH THE EXTENDED PERIOD. A WEAK...BROAD AND FLATTENING UPPER LEVEL RIDGE WILL MOVE INTO THE CENTRAL PLAINS ON WEDNESDAY WITH SEVERAL DISTURBANCES IN THE SOMEWHAT ZONAL FLOW. MODELS SEEM TO BE IN DISAGREEMENT FROM THE VERY START AS THE ECMWF HAS A STRONG SHORTWAVE TROUGH OVER THE SOUTH CENTRAL PLAINS ON WEDNESDAY AND THE GFS BRINGS THE UPPER RIDGE FURTHER EAST INTO THE HIGH PLAINS. THURSDAY INTO FRIDAY...AN UPPER LEVEL TROUGH WILL PUSH INTO THE WESTERN UNITED STATES TRANSITIONING THE FLOW ALOFT TO A SOUTHWEST FLOW. MODELS DISAGREE ONCE AGAIN WITH THE EVOLUTION OF THIS UPPER TROUGH...WITH THE ECMWF DIGGING THE TROUGH FURTHER SOUTH INTO ARIZONA AND NEW MEXICO CLOSING OFF INTO A LOW WHILE THE GFS KEEPS THE UPPER TROUGH FURTHER NORTH AND SENDS A MORE POTENT SHORTWAVE TROUGH THROUGH THE PLAINS ON SATURDAY. GIVEN THE MODEL DISCREPANCIES...WENT AHEAD AND ACCEPTED THE ALLBLEND FOR PRECIPITATION CHANCES WHICH ARE IN EVERYDAY OF THE EXTENDED. SURFACE FEATURES ARE A LITTLE HARDER TO DETERMINE IN THE EXTENDED GIVEN THE LARGE SCALE FEATURES CANNOT EVEN BE RESOLVED BY THE MODELS. THE GFS STILL SHOWS A DRYLINE SETTING UP OVER THE CWA THURSDAY NIGHT AND WAVERING OVER THE CWA THROUGH FRIDAY NIGHT. THIS COULD SERVE AS A BOUNDARY FOR SEVERE THUNDERSTORM INITIATION THURSDAY NIGHT THROUGH FRIDAY NIGHT. INSTABILITY...LOW LEVEL MOISTURE...AND FAVORABLE SHEAR WILL BE PRESENT THROUGHOUT THE EXTENDED AND...IF INTERACTING WITH THE FORCING OF THE DRYLINE...WILL PROVIDE A GOOD ENVIRONMENT FOR SEVERE THUNDERSTORMS. HOWEVER...SINCE MODELS ARE IN SUCH POOR AGREEMENT...WILL HOLD OFF ON GETTING SPECIFIC IN TERMS OF TIMING AND POSITION OF SEVERE THUNDERSTORMS IN THE EXTENDED. TEMPERATURES IN THE EXTENDED WILL BE NEAR NORMAL TO SLIGHTLY ABOVE NORMAL WITH HIGHS GENERALLY IN THE UPPER 80S TO LOW 90S AND LOWS IN THE UPPER 50S WEST TO UPPER 60S AND LOW 70S EAST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1120 AM MDT SUN JUN 22 2014 KGLD...VFR CONDITIONS EXPECTED THROUGH 00Z WITH NORTHEAST WINDS AROUND 10KTS. IN THE 00Z-03Z TIME FRAME CURRENT INDICATIONS ARE FOR A LINE OF STRONG TO SEVERE THUNDERSTORMS TO IMPACT THE TERMINAL WITH WIND GUSTS OVER 45 KTS POSSIBLE ALONG WITH LARGE HAIL AND HEAVY RAINFALL CREATING MVFR CONDITIONS. AFTER 03Z NORTHEAST WINDS GUSTING 15-20KTS WILL DECREASE TO 10KTS OR LESS FROM THE NORTH/NORTHEAST. KMCK...VFR CONDITIONS EXPECTED THROUGH 01Z WITH NORTHEAST WINDS AROUND 10KTS INCREASING AND GUSTING NEAR 20KTS AFTER 22Z. FROM 02Z-05Z CURRENT INDICATIONS ARE FOR A LINE OF STRONG TO SEVERE THUNDERSTORMS TO POSSIBLY IMPACT THE TERMINAL WITH WIND GUSTS TO 35KTS...POSSIBLY SOME SMALL HAIL AND HEAVY RAINFALL CREATING MVFR CONDITIONS. THE STRONGER STORMS AND WINDS ARE CURRENTLY EXPECTED TO BE SOUTH OF THE TERMINAL. AFTER 05Z NORTH TO NORTHEAST WINDS UNDER 10KTS EXPECTED. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...99 LONG TERM...ALW AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1120 AM MDT SUN JUN 22 2014 .UPDATE... ISSUED AT 1025 AM MDT SUN JUN 22 2014 HAVE REDONE THE FIRST AND SECOND PERIODS TO BETTER REFLECT CURRENT OBSERVATIONS AND FINE TUNE TIMING AND AREAL COVERAGE OF THUNDERSTORMS THIS AFTERNOON AND EVENING. FURTHER REVISIONS TO THE FORECAST ARE POSSIBLE AS NEWER MODEL DATA COMES IN. LATEST NAM/RUC/HRRR SUGGESTING SHOWER AND THUNDERSTORM ACTIVITY WILL BEGIN AFTER 3 PM MDT (4 PM CDT) IN FAR EASTERN COLORADO SPREADING EAST ACROSS THE REMAINDER OF THE AREA LATE THIS AFTERNOON THROUGH THE EVENING BEFORE EXITING THE AREA AROUND/SHORTLY AFTER MIDNIGHT. NAM IS IT A BIT QUICKER BRINGING PRECIP INTO THE AREA COMPARED TO THE RUC/HRRR BUT BY 03Z ALL MODELS IN PRETTY GOOD AGREEMENT WITH NUMEROUS SHOWERS AND THUNDERSTORMS IN WESTERN KANSAS AND SOUTHWEST NEBRASKA. HRRR SUGGESTING A LINE OF STORMS WILL MOVE THROUGH WITH THE POTENTIAL FOR LARGE HAIL...DAMAGING WINDS AND LOCALLY HEAVY RAINFALL. HAVE TRENDED TOWARD THE HRRR AND NAM FOR POP PLACEMENT. HIGHS IN THE 80S EXCEPT LOW 90S FROM NORTON TO HILL CITY TO LEOTI AND POINTS EAST. && .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 255 AM MDT SUN JUN 22 2014 UPPER FLOW WILL BE ZONAL TODAY AND TONIGHT TURNING NORTHWESTERLY MONDAY AND TUESDAY. ZONAL FLOW RETURNS TUESDAY NIGHT. A SURFACE TROUGH WILL BE ACROSS NORTHWEST KANSAS TODAY. BY THIS AFTERNOON A FRONT WILL PUSH SOUTH ACROSS NORTHWEST KANSAS. HIGH PRESSURE WILL MOVE INTO THE CENTRAL PLAINS TONIGHT AND CONTINUE THROUGH TUESDAY NIGHT. A SHORTWAVE MOVES EAST OF THE ROCKIES THIS AFTERNOON AND EVENING. THERE IS GOOD LIFT ASSOCIATED WITH THE SHORTWAVE. CAPE RANGES FROM 1800 TO 2400 J/KG AND SHEAR VALUES ARE FROM 35 TO 40 KTS. PRECIPITABLE WATER IS JUST OVER AN INCH ACROSS THE FA. MODELS HAVE CONSISTENTLY SHOWED HIGHER QPF GENERALLY ALIGNED ALONG AND SOUTH OF THE TROUGH AXIS. THE GFS HAS UNUSUALLY LARGE QPF BUT IT IS WELL SOUTH OF THE FA. STORM MOVEMENT RANGES FROM 10 TO 15 KTS BUT IS NOT FAVORABLE TO TRAINING STORMS DUE TO A PERPENDICULAR ORIENTATION TO THE TROUGH AXIS. PLAN TO CONTINUE HIGH POPS AND WORDING FOR POSSIBLE HEAVY RAINFALL SUNDAY AFTERNOON AND EVENING. CHANCES DECREASE OVERNIGHT. SUBSIDENCE WILL KEEP CONDITIONS DRY MONDAY MORNING, BUT BY AFTERNOON EXPECT THUNDERSTORMS TO DEVELOP OVER HIGHER TERRAIN IN COLORADO DUE TO UPSLOPE CONVERGENCE IN THAT AREA. STORMS WILL DRIFT EAST DURING THE AFTERNOON AND EVENING. PLAN TO GO WITH SLIGHT CHANCE POPS MONDAY AFTERNOON WITH CHANCE POPS MONDAY EVENING. A SIMILAR SCENARIO EXISTS FOR TUESDAY WITH STORMS INITIATING OVER THE HIGHER TERRAIN TO THE WEST AND MOVING EAST INTO THE FA. PLAN TO CONTINUE CHANCE POPS FOR TUESDAY/TUESDAY NIGHT. MAX TEMPERATURES WILL RANGE FROM THE MID 80S TO 90 TODAY. COOLER READINGS WILL BE REACHED IN THE UPPER 70S TO LOWER 80S ON MONDAY. MAX TEMPERATURES TUESDAY SHOULD REACH THE LOWER TO MID 80S. MIN TEMPERATURES WILL RANGE FROM THE UPPER 50S TO LOWER 60S WITH LOWER TO MID 60S TUESDAY NIGHT. .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 255 AM MDT SUN JUN 22 2014 MODELS ARE STILL SHOWING A VERY ACTIVE WEATHER PATTERN OVER THE CWA THROUGH THE EXTENDED PERIOD. A WEAK...BROAD AND FLATTENING UPPER LEVEL RIDGE WILL MOVE INTO THE CENTRAL PLAINS ON WEDNESDAY WITH SEVERAL DISTURBANCES IN THE SOMEWHAT ZONAL FLOW. MODELS SEEM TO BE IN DISAGREEMENT FROM THE VERY START AS THE ECMWF HAS A STRONG SHORTWAVE TROUGH OVER THE SOUTH CENTRAL PLAINS ON WEDNESDAY AND THE GFS BRINGS THE UPPER RIDGE FURTHER EAST INTO THE HIGH PLAINS. THURSDAY INTO FRIDAY...AN UPPER LEVEL TROUGH WILL PUSH INTO THE WESTERN UNITED STATES TRANSITIONING THE FLOW ALOFT TO A SOUTHWEST FLOW. MODELS DISAGREE ONCE AGAIN WITH THE EVOLUTION OF THIS UPPER TROUGH...WITH THE ECMWF DIGGING THE TROUGH FURTHER SOUTH INTO ARIZONA AND NEW MEXICO CLOSING OFF INTO A LOW WHILE THE GFS KEEPS THE UPPER TROUGH FURTHER NORTH AND SENDS A MORE POTENT SHORTWAVE TROUGH THROUGH THE PLAINS ON SATURDAY. GIVEN THE MODEL DISCREPANCIES...WENT AHEAD AND ACCEPTED THE ALLBLEND FOR PRECIPITATION CHANCES WHICH ARE IN EVERYDAY OF THE EXTENDED. SURFACE FEATURES ARE A LITTLE HARDER TO DETERMINE IN THE EXTENDED GIVEN THE LARGE SCALE FEATURES CANNOT EVEN BE RESOLVED BY THE MODELS. THE GFS STILL SHOWS A DRYLINE SETTING UP OVER THE CWA THURSDAY NIGHT AND WAVERING OVER THE CWA THROUGH FRIDAY NIGHT. THIS COULD SERVE AS A BOUNDARY FOR SEVERE THUNDERSTORM INITIATION THURSDAY NIGHT THROUGH FRIDAY NIGHT. INSTABILITY...LOW LEVEL MOISTURE...AND FAVORABLE SHEAR WILL BE PRESENT THROUGHOUT THE EXTENDED AND...IF INTERACTING WITH THE FORCING OF THE DRYLINE...WILL PROVIDE A GOOD ENVIRONMENT FOR SEVERE THUNDERSTORMS. HOWEVER...SINCE MODELS ARE IN SUCH POOR AGREEMENT...WILL HOLD OFF ON GETTING SPECIFIC IN TERMS OF TIMING AND POSITION OF SEVERE THUNDERSTORMS IN THE EXTENDED. TEMPERATURES IN THE EXTENDED WILL BE NEAR NORMAL TO SLIGHTLY ABOVE NORMAL WITH HIGHS GENERALLY IN THE UPPER 80S TO LOW 90S AND LOWS IN THE UPPER 50S WEST TO UPPER 60S AND LOW 70S EAST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1120 AM MDT SUN JUN 22 2014 KGLD...VFR CONDITIONS EXPECTED THROUGH 00Z WITH NORTHEAST WINDS AROUND 10KTS. IN THE 00Z-03Z TIME FRAME CURRENT INDICATIONS ARE FOR A LINE OF STRONG TO SEVERE THUNDERSTORMS TO IMPACT THE TERMINAL WITH WIND GUSTS OVER 45 KTS POSSIBLE ALONG WITH LARGE HAIL AND HEAVY RAINFALL CREATING MVFR CONDITIONS. AFTER 03Z NORTHEAST WINDS GUSTING 15-20KTS WILL DECREASE TO 10KTS OR LESS FROM THE NORTH/NORTHEAST. KMCK...VFR CONDITIONS EXPECTED THROUGH 01Z WITH NORTHEAST WINDS AROUND 10KTS INCREASING AND GUSTING NEAR 20KTS AFTER 22Z. FROM 02Z-05Z CURRENT INDICATIONS ARE FOR A LINE OF STRONG TO SEVERE THUNDERSTORMS TO POSSIBLY IMPACT THE TERMINAL WITH WIND GUSTS TO 35KTS...POSSIBLY SOME SMALL HAIL AND HEAVY RAINFALL CREATING MVFR CONDITIONS. THE STRONGER STORMS AND WINDS ARE CURRENTLY EXPECTED TO BE SOUTH OF THE TERMINAL. AFTER 05Z NORTH TO NORTHEAST WINDS UNDER 10KTS EXPECTED. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...99 SHORT TERM...FS LONG TERM...ALW AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1025 AM MDT SUN JUN 22 2014 .UPDATE... ISSUED AT 1025 AM MDT SUN JUN 22 2014 HAVE REDONE THE FIRST AND SECOND PERIODS TO BETTER REFLECT CURRENT OBSERVATIONS AND FINE TUNE TIMING AND AREAL COVERAGE OF THUNDERSTORMS THIS AFTERNOON AND EVENING. FURTHER REVISIONS TO THE FORECAST ARE POSSIBLE AS NEWER MODEL DATA COMES IN. LATEST NAM/RUC/HRRR SUGGESTING SHOWER AND THUNDERSTORM ACTIVITY WILL BEGIN AFTER 3 PM MDT (4 PM CDT) IN FAR EASTERN COLORADO SPREADING EAST ACROSS THE REMAINDER OF THE AREA LATE THIS AFTERNOON THROUGH THE EVENING BEFORE EXITING THE AREA AROUND/SHORTLY AFTER MIDNIGHT. NAM IS IT A BIT QUICKER BRINGING PRECIP INTO THE AREA COMPARED TO THE RUC/HRRR BUT BY 03Z ALL MODELS IN PRETTY GOOD AGREEMENT WITH NUMEROUS SHOWERS AND THUNDERSTORMS IN WESTERN KANSAS AND SOUTHWEST NEBRASKA. HRRR SUGGESTING A LINE OF STORMS WILL MOVE THROUGH WITH THE POTENTIAL FOR LARGE HAIL...DAMAGING WINDS AND LOCALLY HEAVY RAINFALL. HAVE TRENDED TOWARD THE HRRR AND NAM FOR POP PLACEMENT. HIGHS IN THE 80S EXCEPT LOW 90S FROM NORTON TO HILL CITY TO LEOTI AND POINTS EAST. && .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 255 AM MDT SUN JUN 22 2014 UPPER FLOW WILL BE ZONAL TODAY AND TONIGHT TURNING NORTHWESTERLY MONDAY AND TUESDAY. ZONAL FLOW RETURNS TUESDAY NIGHT. A SURFACE TROUGH WILL BE ACROSS NORTHWEST KANSAS TODAY. BY THIS AFTERNOON A FRONT WILL PUSH SOUTH ACROSS NORTHWEST KANSAS. HIGH PRESSURE WILL MOVE INTO THE CENTRAL PLAINS TONIGHT AND CONTINUE THROUGH TUESDAY NIGHT. A SHORTWAVE MOVES EAST OF THE ROCKIES THIS AFTERNOON AND EVENING. THERE IS GOOD LIFT ASSOCIATED WITH THE SHORTWAVE. CAPE RANGES FROM 1800 TO 2400 J/KG AND SHEAR VALUES ARE FROM 35 TO 40 KTS. PRECIPITABLE WATER IS JUST OVER AN INCH ACROSS THE FA. MODELS HAVE CONSISTENTLY SHOWED HIGHER QPF GENERALLY ALIGNED ALONG AND SOUTH OF THE TROUGH AXIS. THE GFS HAS UNUSUALLY LARGE QPF BUT IT IS WELL SOUTH OF THE FA. STORM MOVEMENT RANGES FROM 10 TO 15 KTS BUT IS NOT FAVORABLE TO TRAINING STORMS DUE TO A PERPENDICULAR ORIENTATION TO THE TROUGH AXIS. PLAN TO CONTINUE HIGH POPS AND WORDING FOR POSSIBLE HEAVY RAINFALL SUNDAY AFTERNOON AND EVENING. CHANCES DECREASE OVERNIGHT. SUBSIDENCE WILL KEEP CONDITIONS DRY MONDAY MORNING, BUT BY AFTERNOON EXPECT THUNDERSTORMS TO DEVELOP OVER HIGHER TERRAIN IN COLORADO DUE TO UPSLOPE CONVERGENCE IN THAT AREA. STORMS WILL DRIFT EAST DURING THE AFTERNOON AND EVENING. PLAN TO GO WITH SLIGHT CHANCE POPS MONDAY AFTERNOON WITH CHANCE POPS MONDAY EVENING. A SIMILAR SCENARIO EXISTS FOR TUESDAY WITH STORMS INITIATING OVER THE HIGHER TERRAIN TO THE WEST AND MOVING EAST INTO THE FA. PLAN TO CONTINUE CHANCE POPS FOR TUESDAY/TUESDAY NIGHT. MAX TEMPERATURES WILL RANGE FROM THE MID 80S TO 90 TODAY. COOLER READINGS WILL BE REACHED IN THE UPPER 70S TO LOWER 80S ON MONDAY. MAX TEMPERATURES TUESDAY SHOULD REACH THE LOWER TO MID 80S. MIN TEMPERATURES WILL RANGE FROM THE UPPER 50S TO LOWER 60S WITH LOWER TO MID 60S TUESDAY NIGHT. .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 255 AM MDT SUN JUN 22 2014 MODELS ARE STILL SHOWING A VERY ACTIVE WEATHER PATTERN OVER THE CWA THROUGH THE EXTENDED PERIOD. A WEAK...BROAD AND FLATTENING UPPER LEVEL RIDGE WILL MOVE INTO THE CENTRAL PLAINS ON WEDNESDAY WITH SEVERAL DISTURBANCES IN THE SOMEWHAT ZONAL FLOW. MODELS SEEM TO BE IN DISAGREEMENT FROM THE VERY START AS THE ECMWF HAS A STRONG SHORTWAVE TROUGH OVER THE SOUTH CENTRAL PLAINS ON WEDNESDAY AND THE GFS BRINGS THE UPPER RIDGE FURTHER EAST INTO THE HIGH PLAINS. THURSDAY INTO FRIDAY...AN UPPER LEVEL TROUGH WILL PUSH INTO THE WESTERN UNITED STATES TRANSITIONING THE FLOW ALOFT TO A SOUTHWEST FLOW. MODELS DISAGREE ONCE AGAIN WITH THE EVOLUTION OF THIS UPPER TROUGH...WITH THE ECMWF DIGGING THE TROUGH FURTHER SOUTH INTO ARIZONA AND NEW MEXICO CLOSING OFF INTO A LOW WHILE THE GFS KEEPS THE UPPER TROUGH FURTHER NORTH AND SENDS A MORE POTENT SHORTWAVE TROUGH THROUGH THE PLAINS ON SATURDAY. GIVEN THE MODEL DISCREPANCIES...WENT AHEAD AND ACCEPTED THE ALLBLEND FOR PRECIPITATION CHANCES WHICH ARE IN EVERYDAY OF THE EXTENDED. SURFACE FEATURES ARE A LITTLE HARDER TO DETERMINE IN THE EXTENDED GIVEN THE LARGE SCALE FEATURES CANNOT EVEN BE RESOLVED BY THE MODELS. THE GFS STILL SHOWS A DRYLINE SETTING UP OVER THE CWA THURSDAY NIGHT AND WAVERING OVER THE CWA THROUGH FRIDAY NIGHT. THIS COULD SERVE AS A BOUNDARY FOR SEVERE THUNDERSTORM INITIATION THURSDAY NIGHT THROUGH FRIDAY NIGHT. INSTABILITY...LOW LEVEL MOISTURE...AND FAVORABLE SHEAR WILL BE PRESENT THROUGHOUT THE EXTENDED AND...IF INTERACTING WITH THE FORCING OF THE DRYLINE...WILL PROVIDE A GOOD ENVIRONMENT FOR SEVERE THUNDERSTORMS. HOWEVER...SINCE MODELS ARE IN SUCH POOR AGREEMENT...WILL HOLD OFF ON GETTING SPECIFIC IN TERMS OF TIMING AND POSITION OF SEVERE THUNDERSTORMS IN THE EXTENDED. TEMPERATURES IN THE EXTENDED WILL BE NEAR NORMAL TO SLIGHTLY ABOVE NORMAL WITH HIGHS GENERALLY IN THE UPPER 80S TO LOW 90S AND LOWS IN THE UPPER 50S WEST TO UPPER 60S AND LOW 70S EAST. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 525 AM MDT SUN JUN 22 2014 VFR CONDITIONS ARE EXPECTED AT KGLD AND KMCK UNTIL LATE AFTERNOON AND EVENING. A DISTURBANCE WILL INITIATE THUNDERSTORMS ALONG A TROUGH AXIS IN NORTHWEST KANSAS THIS AFTERNOON. SOME BRIEF MVFR CONDITIONS ARE POSSIBLE NEAR STORMS. A FRONT WILL MOVE SOUTH INTO NORTHWEST KANSAS PRODUCING BREEZY CONDITIONS LATE THIS AFTERNOON AND EVENING. THUNDERSTORMS SHOULD GRADUALLY END LATE THIS EVENING. FORECAST SOUNDINGS INDICATE LOW CIGS AND MVFR RETURNING TO BOTH TERMINALS EARLY MONDAY MORNING. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...99 SHORT TERM...FS LONG TERM...ALW AVIATION...FS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1153 PM CDT Sat Jun 21 2014 ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Sunday) Issued at 315 PM CDT SAT JUN 21 2014 19Z water vapor imagery continues to shows a quasi-zonal flow across the central Rockies and into the plains. There may be one or two Mesoscale Convective Vortices (MCV) moving along the KS/NEB state line with the more obvious one crossing the MO river and headed into central MO. There also appears to be a subtle shortwave moving through ID and northern UT. At the surface, a trough of low pressure extended from the Dakotas south through eastern CO. Surface OBS show the better low level moisture has shifted a little to the east with much of the 70 degree dewpoints. Late this afternoon and this evening is anticipated to be mostly dry with general subsidence from the MCV over eastern KS and the deeper moisture to the east of the area. This combined with a lack of organized low level convergence should favor any isolated storms remaining east of the forecast area. Will have to watch and see if any of the convection off the higher terrain holds together long enough to reach north central KS. There are some indications from the RAP and HRRR that there could be some precip move into Republic and Cloud counties around midnight. However those solutions seem to be a little to aggressive in developing convection earlier in the day, so I don`t know how much weight to give these solutions. Will have some small POPs after midnight for far northern counties in case some shower and thunderstorm activity is able to hang together. Lows tonight should once again be mild with readings around 70 due to southerly winds and warm air remaining over the area. For Sunday, the subtle shortwave out west is progged to be moving out into the plains, mainly to the north of the forecast area. However the synoptic scale surface trough is expected to be a little further east into KS. Convergence along this boundary coupled with some weak forcing from the upper wave could cause a broken line of storms to form by the afternoon hours. Instability is expected to be high once again with good low level moisture still in place. However due to weak mid level flow, deep layer shear is progged to only be from 15 to 25 kts. This would favor multi cell clusters with a hail and strong wind hazard. North central KS looks like the most likely place for this storms to form during the afternoon. Temps for Sunday are expected to be similar to today`s or maybe a degree or two cooler. Models show a slight cooling trend at 850 and there could be higher clouds increasing by the afternoon from the potential convection to the west. Because of this have highs generally in the lower 90s. .LONG TERM...(Sunday Night through Saturday) Issued at 315 PM CDT SAT JUN 21 2014 Overall trend is for the upper wave to be less intense as it passes through Sunday night into early Monday. Still looks like a good opportunity for for most locations to receive at least one round of precip with the slow moving system weak front moving through a moist early-summer airmass and limited inhibition. Severe weather concerns should diminish with time in the evening hours with a least some chance for pockets of heavier precipitation, though setup does not point to any particularly area at this point. Monday should slowly dry with the departing wave with Monday night and much of Tuesday still looking to be the more likely dry periods of this forecast. Models do show some similarities with a weak wave passing mainly south of the area late Tuesday into Wednesday, but moisture does return north with this wave with modest flow keeping mid levels from warming too fast for at least small thunderstorm chances. Upper flow amplifies over the western and eventually central CONUS into the end of the forecast. Expect capping to increase enough for a mainly dry end to the work week with chances picking up again by Saturday as forcing increases. Temps should slowly warm through the latter portions of the week, with 90s possible by Saturday. && .AVIATION...(For the 06Z TAFs through 06Z Sunday Night) Issued at 1146 PM CDT SAT JUN 21 2014 VFR conditions expected through mid day today. A boundary will approach from central KS during the evening hours causing widespread thunderstorms late in the period. There is also the possibility of isolated to scattered storms out ahead of the boundary near the taf sites in the late afternoon due to daytime heating. The lift for this convection could be enhanced by a shortwave although the there is a lack of surface convergence. Timing of the shortwave and any outflow that could potential contribute to convergence at the surface is uncertain and will need time to evaluate. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Wolters LONG TERM...65 AVIATION...Sanders
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
713 AM EDT SUN JUN 22 2014 .UPDATE... ISSUED AT 705 AM EDT SUN JUN 22 2014 THE DENSE FOG ADVISORY REMAINS IN EFFECT FOR THE SOUTHWEST PART OF THE CWA. IT WAS SENT OUT A BIT EARLIER AS I35...W39...LOZ AND SME ALL WERE REPORTING DENSE FOG. THE DENSE FOG IN THAT AREA SHOULD LIFT AND BEGIN TO DISSIPATE BY 9 AM EDT. HOURLY TEMPERATURE AND DEWPOINT GRIDS AS WELL AS SKY COVER HAS BEEN ADJUSTED BASED ON RECENT TRENDS. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 355 AM EDT SUN JUN 22 2014 THE PATTERN ACROSS THE CONUS REMAINS RATHER ZONAL THIS MORNING. AN UPPER LEVEL RIDGE WAS CENTERED OVER THE WESTERN GULF OF MEXICO REGION AND SOUTHEASTERN CONUS AND EXTENDED INTO THE MS VALLEY. A TROUGH IS GRADUALLY DEPARTING THE NORTHEASTERN CONUS. THIS PUTS THE REGION IN WEST NORTHWEST TO NORTHWEST FLOW ALOFT WITH MAINLY CIRRUS DROPPING ACROSS THE AREA. PATCHY DENSE VALLEY FOG HAS FORMED IN VALLEY LOCATIONS AND BASED ON RECENT ASOS AND AWOS OBS MAY BE A BIT MORE WIDESPREAD IN PARTS OF THE CUMBERLAND VALLEY. SO FAR AN SPS HAS BEEN ISSUED FOR THE DENSE FOG ACROSS THE SOUTHWEST PART OF THE CWA. THIS WILL CONTINUE TO BE MONITORED OVER THE NEXT FEW HOURS. FOG SHOULD GRADUALLY BEGIN TO LIFT AFTER SUNRISE AND DISSIPATE BY AROUND 9 TO 10 AM. OTHERWISE...A COUPLE OF WEAK SHORTWAVES ARE EXPECTED TO WORK ACROSS THE OH VALLEY AND EASTERN KY THIS AFTERNOON AND THIS EVENING. AT THE SAME TIME...THE BOUNDARY THAT SAGGED SOUTH INTO THE AREA WILL REMAIN NEARLY STATIONARY OVER THE SOUTHWEST PART OF THE CWA...OR JUST TO THE SOUTH AND WEST OF THAT REGION. DRIER DEWPOINTS ACROSS THE NORTHERN AND EASTERN PART OF THE CWA MAY INITIALLY INHIBIT CONVECTION A BIT...AS POSSIBLY THE MID LEVEL RIDGING TO OUR WEST. RECENT RUNS OF THE RAP HAVE CONVECTION DEVELOPING NORTHWEST OF THE AREA IN THE AFTERNOON AND APPROACHING THE AREA TOWARD SUNSET...BUT TENDS OF WEAKEN IT LATE. THE 0Z NAM BRINGS SOME CONVECTION ACROSS THE REGION AROUND SUNSET AND THE 0Z GFS IS RATHER SIMILAR. WITH THE BOUNDARY IN THE VICINITY AND THE FACT THAT FORECAST SOUNDINGS GENERALLY DO NOT INDICATE THAT THERE WILL BE SIGNIFICANT CAPPING...BUT FORCING WILL BE RATHER WEAK OPTED TO CONTINUE WITH SLIGHT CHANCES FROM MID AFTERNOON INTO THE EVENING HOURS. THEREAFTER...A DIURNAL INCREASE IN CONVECTION IS ANTICIPATED OVERNIGHT TONIGHT...AS THE MID LEVEL RIDGING BUILDS IN AND HEIGHTS RISE FURTHER. PATCHY VALLEY FOG SHOULD AGAIN DEVELOP. THE MID LEVEL RIDGING SHOULD GRADUALLY SHIFT EAST OF THE AREA ON MONDAY WITH A SHORTWAVE TROUGH APPROACHING FROM THE WEST. THIS SHOULD ALSO LEAD TO THE STATIONARY BOUNDARY LIFTING ACROSS THE AREA AS A WARM FRONT. 850 MB TEMPS SHOULD CLIMB TOWARD AT LEAST 18C. WIDESPREAD LOWER 90S ARE EXPECTED FOR HIGHS OUTSIDE OF THE HIGHER TERRAIN. THE LIFTING WARM FRONT AND HEIGHT FALLS LATE SHOULD COMBINE WITH DAYTIME HEATING FOR SCATTERED CONVECTION...ESPECIALLY FROM MID AFTERNOON INTO THE EVENING. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 402 AM EDT SUN JUN 22 2014 THE PATTERN ACROSS THE CONUS CONTINUES A MAINLY ZONAL FLOW ACROSS THE NORTHERN PART OF THE COUNTRY WITH WEAKENED RIDGING OVER THE SOUTH. THIS IS MAINTAINED...AT LEAST FOR THE FIRST HALF OF THE EXTENDED. ON TUESDAY...A SEEMINGLY WEAKER SHORTWAVE FROM RUN TO RUN TRIES TO PUSH ACROSS THE LOWER GREAT LAKES AND AT THE SURFACE...BRINGS A WEAK COLD FRONT ACROSS THE OH VALLEY. TOWARDS THE LAST FEW DAYS OF THE EXTENDED...THE PATTERN BEGINS TO TRANSITION TO A MORE AMPLIFIED PATTERN WITH DEVELOPING RIDGING ALONG THE MS RIVER VALLEY AND TROUGHS DIGGING ALONG THE THE WEST COAST AND ALSO ALONG THE EAST COAST. ONE SLIGHT CHANGE IN RECENT RUNS SHOWS A WAVE UNDER CUTTING THE RIDGE AND DRIFTING INTO THE MID MS VALLEY AND INTO THE TN VALLEY BY THE END OF THE EXTENDED. OTHERWISE...THROUGH THE EXTENDED...A WARM...MOIST...AND UNSTABLE AIR MASS REMAINS OVER EASTERN KENTUCKY. THIS WILL CONTINUE THE AFTERNOON MAXIMUM CHANCE FOR PRECIP DWINDLING TO THE MINIMUM CHANCE OF PRECIP INTO THE OVERNIGHT HOURS. THE ONE CHANCE OF DISRUPTING THIS TREND WOULD BE THE ARRIVAL OF AN MCS THROUGH THE AREA...WHICH IS A POSSIBILITY. OTHERWISE...DID NOT STRAY FROM THE MODEL ALL BLEND. THIS PATTERN MAY BE COMING TO AN END BY THE END OF THE EXTENDED WITH THE MODELS HINTING AT STRONG RIDGING BUILDING AND SHIFTING EAST OF THE MS. OTHERWISE...HUMID...WARM...AND UNSTABLE DAYS ARE TO CONTINUE. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 705 AM EDT SUN JUN 22 2014 THE MOST IMPACTED AIRPORTS FROM INITIAL DENSE FOG WILL BE KLOZ AND KSME. SOME MAY ALSO LIFT INTO SJS EARLY. THERE IS NO FOG NOW AT JKL AND WE DO NOT EXPECT THIS TO CHANGE. WITH DAYTIME HEATING...INSTABILITY WILL INCREASE AND THE THREAT OF AN ISOLATED SHRA OR TSRA AFTER 16Z...BUT PROBABILITIES AND CONFIDENCE IN THIS IS TOO LOW TO INCLUDE ATTM. MORE VALLEY FOG SHOULD FORM LATE IN THE PERIOD...BUT THIS SHOULD TEND TO NOT AFFECT THE TAF SITES UNLESS ONE TAKES A DIRECT HIT FROM SHOWERS OR THUNDERSTORMS LATER TODAY. && .JKL WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR KYZ068-069- 079-080-083>088-115>118. && $$ UPDATE...JP SHORT TERM...JP LONG TERM...SHALLENBERGER AVIATION...JP
AREA FORECAST DISCUSSION
NWS JACKSON KY
402 AM EDT SUN JUN 22 2014 .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 355 AM EDT SUN JUN 22 2014 THE PATTERN ACROSS THE CONUS REMAINS RATHER ZONAL THIS MORNING. AN UPPER LEVEL RIDGE WAS CENTERED OVER THE WESTERN GULF OF MEXICO REGION AND SOUTHEASTERN CONUS AND EXTENDED INTO THE MS VALLEY. A TROUGH IS GRADUALLY DEPARTING THE NORTHEASTERN CONUS. THIS PUTS THE REGION IN WEST NORTHWEST TO NORTHWEST FLOW ALOFT WITH MAINLY CIRRUS DROPPING ACROSS THE AREA. PATCHY DENSE VALLEY FOG HAS FORMED IN VALLEY LOCATIONS AND BASED ON RECENT ASOS AND AWOS OBS MAY BE A BIT MORE WIDESPREAD IN PARTS OF THE CUMBERLAND VALLEY. SO FAR AN SPS HAS BEEN ISSUED FOR THE DENSE FOG ACROSS THE SOUTHWEST PART OF THE CWA. THIS WILL CONTINUE TO BE MONITORED OVER THE NEXT FEW HOURS. FOG SHOULD GRADUALLY BEGIN TO LIFT AFTER SUNRISE AND DISSIPATE BY AROUND 9 TO 10 AM. OTHERWISE...A COUPLE OF WEAK SHORTWAVES ARE EXPECTED TO WORK ACROSS THE OH VALLEY AND EASTERN KY THIS AFTERNOON AND THIS EVENING. AT THE SAME TIME...THE BOUNDARY THAT SAGGED SOUTH INTO THE AREA WILL REMAIN NEARLY STATIONARY OVER THE SOUTHWEST PART OF THE CWA...OR JUST TO THE SOUTH AND WEST OF THAT REGION. DRIER DEWPOINTS ACROSS THE NORTHERN AND EASTERN PART OF THE CWA MAY INITIALLY INHIBIT CONVECTION A BIT...AS POSSIBLY THE MID LEVEL RIDGING TO OUR WEST. RECENT RUNS OF THE RAP HAVE CONVECTION DEVELOPING NORTHWEST OF THE AREA IN THE AFTERNOON AND APPROACHING THE AREA TOWARD SUNSET...BUT TENDS OF WEAKEN IT LATE. THE 0Z NAM BRINGS SOME CONVECTION ACROSS THE REGION AROUND SUNSET AND THE 0Z GFS IS RATHER SIMILAR. WITH THE BOUNDARY IN THE VICINITY AND THE FACT THAT FORECAST SOUNDINGS GENERALLY DO NOT INDICATE THAT THERE WILL BE SIGNIFICANT CAPPING...BUT FORCING WILL BE RATHER WEAK OPTED TO CONTINUE WITH SLIGHT CHANCES FROM MID AFTERNOON INTO THE EVENING HOURS. THEREAFTER...A DIURNAL INCREASE IN CONVECTION IS ANTICIPATED OVERNIGHT TONIGHT...AS THE MID LEVEL RIDGING BUILDS IN AND HEIGHTS RISE FURTHER. PATCHY VALLEY FOG SHOULD AGAIN DEVELOP. THE MID LEVEL RIDGING SHOULD GRADUALLY SHIFT EAST OF THE AREA ON MONDAY WITH A SHORTWAVE TROUGH APPROACHING FROM THE WEST. THIS SHOULD ALSO LEAD TO THE STATIONARY BOUNDARY LIFTING ACROSS THE AREA AS A WARM FRONT. 850 MB TEMPS SHOULD CLIMB TOWARD AT LEAST 18C. WIDESPREAD LOWER 90S ARE EXPECTED FOR HIGHS OUTSIDE OF THE HIGHER TERRAIN. THE LIFTING WARM FRONT AND HEIGHT FALLS LATE SHOULD COMBINE WITH DAYTIME HEATING FOR SCATTERED CONVECTION...ESPECIALLY FROM MID AFTERNOON INTO THE EVENING. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 402 AM EDT SUN JUN 22 2014 THE PATTERN ACROSS THE CONUS CONTINUES A MAINLY ZONAL FLOW ACROSS THE NORTHERN PART OF THE COUNTRY WITH WEAKENED RIDGING OVER THE SOUTH. THIS IS MAINTAINED...AT LEAST FOR THE FIRST HALF OF THE EXTENDED. ON TUESDAY...A SEEMINGLY WEAKER SHORTWAVE FROM RUN TO RUN TRIES TO PUSH ACROSS THE LOWER GREAT LAKES AND AT THE SURFACE...BRINGS A WEAK COLD FRONT ACROSS THE OH VALLEY. TOWARDS THE LAST FEW DAYS OF THE EXTENDED...THE PATTERN BEGINS TO TRANSITION TO A MORE AMPLIFIED PATTERN WITH DEVELOPING RIDGING ALONG THE MS RIVER VALLEY AND TROUGHS DIGGING ALONG THE THE WEST COAST AND ALSO ALONG THE EAST COAST. ONE SLIGHT CHANGE IN RECENT RUNS SHOWS A WAVE UNDER CUTTING THE RIDGE AND DRIFTING INTO THE MID MS VALLEY AND INTO THE TN VALLEY BY THE END OF THE EXTENDED. OTHERWISE...THROUGH THE EXTENDED...A WARM...MOIST...AND UNSTABLE AIR MASS REMAINS OVER EASTERN KENTUCKY. THIS WILL CONTINUE THE AFTERNOON MAXIMUM CHANCE FOR PRECIP DWINDLING TO THE MINIMUM CHANCE OF PRECIP INTO THE OVERNIGHT HOURS. THE ONE CHANCE OF DISRUPTING THIS TREND WOULD BE THE ARRIVAL OF AN MCS THROUGH THE AREA...WHICH IS A POSSIBILITY. OTHERWISE...DID NOT STRAY FROM THE MODEL ALL BLEND. THIS PATTERN MAY BE COMING TO AN END BY THE END OF THE EXTENDED WITH THE MODELS HINTING AT STRONG RIDGING BUILDING AND SHIFTING EAST OF THE MS. OTHERWISE...HUMID...WARM...AND UNSTABLE DAYS ARE TO CONTINUE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 155 AM EDT SUN JUN 22 2014 THERE SHOULD BE AN OVERALL DECREASE IN CLOUD COVER THROUGH 12Z...ESPECIALLY ANY MID OR LOW CLOUDS...THOUGH BANDS OF MID AND HIGH CLOUDS SHOULD PASS FROM TIME TO TIME INTO SUNDAY. PATCHY VALLEY FOG SHOULD ALSO GRADUALLY DEVELOP THROUGH 9Z AT LOZ...SME AND PROBABLY LIFT INTO SJS. THE MOST IMPACTED AIRPORTS BEING KLOZ AND KSME WHERE RAIN HAD FALLEN EARLIER IN THE DAY. WITH A LARGER CURRENT DEWPOINT DEPRESSION AT JKL..LEFT OUT ANY FOG THERE. THE FOG WILL LIFT AND DISSIPATE BY ABOUT 13Z. WITH DAYTIME HEATING...INSTABILITY WILL INCREASE AND THE THREAT OF AN ISOLATED SHRA OR TSRA AFTER 16Z...BUT PROBABILITIES AND CONFIDENCE IN THIS IS TOO LOW TO INCLUDE ATTM. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...JP LONG TERM...SHALLENBERGER AVIATION...JP
AREA FORECAST DISCUSSION
NWS JACKSON KY
401 AM EDT SUN JUN 22 2014 .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 355 AM EDT SUN JUN 22 2014 THE PATTERN ACROSS THE CONUS REMAINS RATHER ZONAL THIS MORNING. AN UPPER LEVEL RIDGE WAS CENTERED OVER THE WESTERN GULF OF MEXICO REGION AND SOUTHEASTERN CONUS AND EXTENDED INTO THE MS VALLEY. A TROUGH IS GRADUALLY DEPARTING THE NORTHEASTERN CONUS. THIS PUTS THE REGION IN WEST NORTHWEST TO NORTHWEST FLOW ALOFT WITH MAINLY CIRRUS DROPPING ACROSS THE AREA. PATCHY DENSE VALLEY FOG HAS FORMED IN VALLEY LOCATIONS AND BASED ON RECENT ASOS AND AWOS OBS MAY BE A BIT MORE WIDESPREAD IN PARTS OF THE CUMBERLAND VALLEY. SO FAR AN SPS HAS BEEN ISSUED FOR THE DENSE FOG ACROSS THE SOUTHWEST PART OF THE CWA. THIS WILL CONTINUE TO BE MONITORED OVER THE NEXT FEW HOURS. FOG SHOULD GRADUALLY BEGIN TO LIFT AFTER SUNRISE AND DISSIPATE BY AROUND 9 TO 10 AM. OTHERWISE...A COUPLE OF WEAK SHORTWAVES ARE EXPECTED TO WORK ACROSS THE OH VALLEY AND EASTERN KY THIS AFTERNOON AND THIS EVENING. AT THE SAME TIME...THE BOUNDARY THAT SAGGED SOUTH INTO THE AREA WILL REMAIN NEARLY STATIONARY OVER THE SOUTHWEST PART OF THE CWA...OR JUST TO THE SOUTH AND WEST OF THAT REGION. DRIER DEWPOINTS ACROSS THE NORTHERN AND EASTERN PART OF THE CWA MAY INITIALLY INHIBIT CONVECTION A BIT...AS POSSIBLY THE MID LEVEL RIDGING TO OUR WEST. RECENT RUNS OF THE RAP HAVE CONVECTION DEVELOPING NORTHWEST OF THE AREA IN THE AFTERNOON AND APPROACHING THE AREA TOWARD SUNSET...BUT TENDS OF WEAKEN IT LATE. THE 0Z NAM BRINGS SOME CONVECTION ACROSS THE REGION AROUND SUNSET AND THE 0Z GFS IS RATHER SIMILAR. WITH THE BOUNDARY IN THE VICINITY AND THE FACT THAT FORECAST SOUNDINGS GENERALLY DO NOT INDICATE THAT THERE WILL BE SIGNIFICANT CAPPING...BUT FORCING WILL BE RATHER WEAK OPTED TO CONTINUE WITH SLIGHT CHANCES FROM MID AFTERNOON INTO THE EVENING HOURS. THEREAFTER...A DIURNAL INCREASE IN CONVECTION IS ANTICIPATED OVERNIGHT TONIGHT...AS THE MID LEVEL RIDGING BUILDS IN AND HEIGHTS RISE FURTHER. PATCHY VALLEY FOG SHOULD AGAIN DEVELOP. THE MID LEVEL RIDGING SHOULD GRADUALLY SHIFT EAST OF THE AREA ON MONDAY WITH A SHORTWAVE TROUGH APPROACHING FROM THE WEST. THIS SHOULD ALSO LEAD TO THE STATIONARY BOUNDARY LIFTING ACROSS THE AREA AS A WARM FRONT. 850 MB TEMPS SHOULD CLIMB TOWARD AT LEAST 18C. WIDESPREAD LOWER 90S ARE EXPECTED FOR HIGHS OUTSIDE OF THE HIGHER TERRAIN. THE LIFTING WARM FRONT AND HEIGHT FALLS LATE SHOULD COMBINE WITH DAYTIME HEATING FOR SCATTERED CONVECTION...ESPECIALLY FROM MID AFTERNOON INTO THE EVENING. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 359 AM EDT SUN JUN 22 2014 THE LONG TERM DISCUSSION WILL BE ISSUED SHORTLY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 155 AM EDT SUN JUN 22 2014 THERE SHOULD BE AN OVERALL DECREASE IN CLOUD COVER THROUGH 12Z...ESPECIALLY ANY MID OR LOW CLOUDS...THOUGH BANDS OF MID AND HIGH CLOUDS SHOULD PASS FROM TIME TO TIME INTO SUNDAY. PATCHY VALLEY FOG SHOULD ALSO GRADUALLY DEVELOP THROUGH 9Z AT LOZ...SME AND PROBABLY LIFT INTO SJS. THE MOST IMPACTED AIRPORTS BEING KLOZ AND KSME WHERE RAIN HAD FALLEN EARLIER IN THE DAY. WITH A LARGER CURRENT DEWPOINT DEPRESSION AT JKL..LEFT OUT ANY FOG THERE. THE FOG WILL LIFT AND DISSIPATE BY ABOUT 13Z. WITH DAYTIME HEATING...INSTABILITY WILL INCREASE AND THE THREAT OF AN ISOLATED SHRA OR TSRA AFTER 16Z...BUT PROBABILITIES AND CONFIDENCE IN THIS IS TOO LOW TO INCLUDE ATTM. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...JP LONG TERM...SHALLENBERGER AVIATION...JP
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1252 AM EDT Sun Jun 22 2014 ...Updated Aviation Discussion... ...Forecast Update... Issued at 917 PM EDT Sat Jun 21 2014 Ran another update this evening mainly to bring grids up to speed with current observations. As expected, convection is rapidly weakening off to the northwest as the precipitation encounters a much drier and more stable airmass. Therefore, will continue to leave the forecast dry overnight. Also went ahead and added some patchy fog to the grids across the Lake Cumberland region where the heaviest rainfall fell this afternoon/evening. Otherwise, the rest of the forecast looks on track. Issued at 614 PM EDT Sat Jun 21 2014 Quick update this evening to account for ongoing trends. Despite a few very isolated light showers, precipitation has ended across southern KY. Therefore, will remove precip mention from the forecast for the remainder of the evening hours. Attention will then turn to the northwest as a line of showers and thunderstorms continues to develop across IL/MO. The main forecast challenge tonight will be just how far east that convection makes it. Given it will be fighting much drier air that has protruded into southern IN and into southern IL, think this convection will likely struggle as it pushes east. However, the latest HRRR which has a good handle on the current convection, does bring a weakening line into southern IN around 06Z overnight. Given the drier air firmly in place, will continue with a dry forecast but will continue to monitor trends over the next few hours. .SHORT TERM (Now through Sunday Night)... Issued at 300 PM EDT Sat Jun 21 2014 The upper air pattern shows a progressive relatively flat flow at 500mb confined generally to the northern tier of states. Weak northwest flow currently over the northern Ohio Valley will become weaker as ridging is forecast to develop across the Lower Mississippi Valley by late Sunday, extending northeastwards through southern Indiana. Expect only a few flat cumulus this afternoon along and north of Interstate 64 as the shortwave that brought scattered thunderstorms earlier this morning to the Lake Cumberland Region moves farther southeast. Any additional isolated thunderstorms through late afternoon will stay along and southeast of the Cumberland Parkway. Expect mostly clear skies tonight with humid conditions and light winds. Some patchy fog may once again develop across southern Indiana and the Bluegrass Region, although not to the extent of earlier this morning. Lows tonight will range from the mid 60s across the Bluegrass and southern Indiana to near 70 elsewhere. Despite adequate moisture and quite unstable conditions developing Sunday afternoon, ridging aloft will inhibit any widespread convection. Think that scattered thunderstorms may develop farther north across Illinois and Indiana, with isolated storms at best along and north of the Ohio River. Expect south central Kentucky to stay dry. Highs Sunday will range from the upper 80s northeast to the lower 90s southwest. Light south winds will develop Sunday afternoon. .LONG TERM (Monday through Saturday)... Issued at 255 PM EDT Sat Jun 21 2014 Fairly typical summertime conditions expected for most of the upcoming week, with a low-amplitude and somewhat progressive pattern aloft. Shortwave ridging on Monday will most likely allow for the warmest temps of the week. However, the pattern is still just flat enough and heights not getting into legitimate heat wave territory, so expect temps to reach the lower 90s in most spots. This stays in line with the more consistent and slightly cooler NAM MOS. Chance POPs will re-enter the picture Monday afternoon as the ridging begins to gradually weaken. Best chance for showers and storms will be Tuesday into Tuesday night, with the passage of an upper shortwave trof. High PWATs will support a heavy rain and pulse wind threat. The rest of the week will not see any real pattern change, but just warm and humid conditions with isolated/scattered storms each day, mainly in the afternoons. Pattern aloft starts to amplify toward the end of the week with a ridge nosing up into the Upper Midwest. This bears watch for a possible break in our daily convection and temps possibly punching back into the 90s at some point next weekend. && .AVIATION (06Z TAF Update)... Issued at 1250 AM EDT Sun Jun 22 2014 Skies will be variably cloudy overnight as some upper level debris from earlier convection moves overhead. Meanwhile, high pressure will be in control at the surface with mostly calm winds. Will continue to leave mention of some MVFR fog at BWG/LEX toward dawn, although the variable cloudiness could limit potential somewhat. GLW has already dropped to 7SM adding confidence that it should be left in. Otherwise, expect light winds later today, with any noticeable gradient out of the SW. Conditions will become unstable in the afternoon although thunderstorm coverage is expected to be limited to isolated due to the upper ridge overhead. Do expect few-sct Cu around 5 K feet in the afternoon. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update.........KJD Short Term.....JSD Long Term......RAS Aviation.......BJS
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1150 PM EDT MON JUN 23 2014 .AVIATION... //DISCUSSION... SHRAS AND A FEW TSRAS WILL LIFT NORTH OF TERMINALS OVERNIGHT WITH WARM FRONTAL BOUNDARY. HOWEVER...ADDITIONAL ACTIVITY WILL SPREAD INTO THE AREA TUESDAY MORNING AS LOW PRESSURE LIFTS INTO THE NORTERN GREAT LAKES AND COLD FRONT MOVES INTO THE AREA. WILL LIMIT TEMPO GROUPS TO 08Z SOUTH...10Z NORTH AND BRING SHRAS/TSRAS BACK IN THE 14Z-15Z TIME FRAME AS FORCING FROM APPROACHING COLD FRONT COINCIDES WITH INCREASING BROADSCALE LIFT AS SHORTWAVE LIFTS NORTHEAST INTO AREA ALONG THE BOUNDARY FROM THE SOUTHERN MISSISSIPPI VALLEY. CLEARING WILL THEN ENSUE LATE IN THE FORECAST AS THIS MAIN UPPER LEVEL TROUGH AXIS PROGRESSES EAST OF TH REGION. //DTW THRESHOLD THREATS... * MEDIUM CONFIDENCE IN CEILINGS BELOW 5KFT BY TUESDAY MORNING. * MEDIUM CONFIDENCE IN THUNDERSTORMS AFFECTING KDTW TUESDAY. && .PREV DISCUSSION...ISSUED 349 PM EDT MON JUN 23 2014 SHORT TERM...THIS AFTERNOON AND TONIGHT AT 19Z THE SURFACE WARM FRONT WAS DRAPED ROUGHLY ALONG THE MICHIGAN STATE BORDER PER REGIONAL OBSERVATIONS. NORTH OF THE FRONT, SHOWERS ASSOCIATED WITH THIS MORNING`S MCV CONTINUE EXITING EAST. THIS LIGHT PRECIP AND ASSOCIATED CLOUD COVER HAS KEPT TEMPERATURES CONFINED TO THE LOW/MID 70S THROUGH MID-AFTERNOON. SOUTH OF THE WARM FRONT, TEMPERATURES IN THE MID 80S AND DEWPOINTS NEAR 70 ARE CONTRIBUTING TO A MODERATE TO STRONGLY UNSTABLE ENVIRONMENT CHARACTERIZED BY A WEAK/UNIDIRECTIONAL AMBIENT WIND FIELD. WITHIN SAID WARM SECTOR, WIDESPREAD MULTICELL CONVECTION IS ONGOING WITH ONLY ISOLATED SEVERE REPORTS THUS FAR. HOWEVER, SUFFICIENT BOUNDARY LAYER RECOVERY SOUTH OF THE WARM FRONT, MOST LIKELY SOUTH OF I-94, WILL HAVE THE POTENTIAL TO CONTRIBUTE TO A WELL-MIXED ENVIRONMENT THROUGH THE LOWEST 5KFT PER THE LATEST RAP FORECAST SOUNDINGS. THIS, IN THE PRESENCE OF LOCALLY ENHANCED SHEAR INVOF THE WARM FRONT, WILL PRESENT A LOW-END CHANCE FOR BRIEF ORGANIZED UPDRAFTS CAPABLE OF PRODUCING A MARGINAL DIABATICALLY-INDUCED SEVERE WIND THREAT UNTIL DIURNAL HEATING IS LOST LATER THIS EVENING. THUNDERSTORM POTENTIAL WILL PERSIST THROUGH THE NIGHT AS THE AREA BECOMES INCREASINGLY ENTRENCHED IN THE WARM SECTOR. ONE LINE OF THUNDERSTORMS HAS DEVELOPED ALONG A LINE FROM SOUTH BEND TO TERRE HAUTE ALONG THE LEAD EDGE OF THE MID-LEVEL MOISTURE TRANSPORT AXIS. IN ADDITION, MORE UPSTREAM DEVELOPMENT HAS BEGUN JUST SOUTH OF CHICAGO IN ASSOCIATION WITH AN MCV EVIDENT IN AFTERNOON VISIBLE IMAGERY. THIS ACTIVITY WILL SPREAD EAST THROUGH MIDNIGHT, WITH THE LAST ROUND LIKELY AFFECTING THE METRO AREA SOMETIME AROUND 02-03Z. THE PRIMARY THREATS WITH LATE EVENING/EARLY NIGHT ACTIVITY WILL BE HEAVY RAIN DUE TO POTENTIAL TRAINING AND PWATS OF 1.6" TO 1.8" ALONG WITH LIGHTNING. SEVERE WIND POTENTIAL WILL DIMINISH WITH TIME AS THE SUN ANGLE DECREASES. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL REMAIN POSSIBLE THROUGH TONIGHT AS THE MID-LEVEL THERMAL GRADIENT RESPONDS TO AN ENCROACHING NORTHERN STREAM WAVE. THE AGEOSTROPHIC RESPONSE SHOULD BE JUST ENOUGH TO KEEP ACTIVITY BUBBLING WITHIN THE MOISTURE AXIS THROUGH THE NOCTURNAL PERIOD. LOWS IN THE WARM SECTOR WILL STRUGGLE TO FALL BELOW 70 DEGREES. LONG TERM...TUESDAY THROUGH SUNDAY GENERALLY ILL-DEFINED FORCING IN A MOIST ENVIRONMENT /PW 1.5-2 INCHES/ POSES CHALLENGES FOR DETERMINING POPS TUESDAY...BUT TRIED TO KEY IN ON SOME FEATURES WITH THIS PACKAGE. WEAK SURFACE CIRCULATION WILL BE LOCATED NEAR CENTRAL LAKE HURON AT 12Z TUESDAY AND MOVING NORTHEAST...LIKELY ACCOMPANIED BY AN AREA OF SHOWERS/T-STORMS. A WEAK SURFACE TROUGH WILL EXTEND SOUTHWARD FROM THIS LOW...BISECTING LOWER MICHIGAN. MEANWHILE...A SHORTWAVE CURRENTLY NOTED ON WATER VAPOR OVER OKLAHOMA WILL PROGRESS NORTHEASTWARD...REACHING IN/OH BY 00Z WEDNESDAY. WEAK AREA OF MIDLEVEL DEFORMATION NORTH OF THIS WAVE MAY PROVIDE SOME LIFT OVER SE MI...ALONG WITH RIGHT ENTRANCE REGION FORCING FROM 70KT JET OVER NORTHERN LOWER. HAVE HIGHLIGHTED THIS FORCING BY UPGRADING THE SOUTHEAST THIRD OF THE CWA TO ENTRY-LEVEL LIKELY POPS FROM 15-21Z. ALSO LOWERED HIGHS A COUPLE DEGREES OVER THE SOUTH TO ACCOUNT FOR EXPECTED ACTIVITY. OTHERWISE...SHOWER/STORM ACTIVITY IS POSSIBLE IN THE MORNING ALONG THE SURFACE TROUGH. SEVERE POTENTIAL DOES NOT LOOK TOO OVERWHELMING...ESPECIALLY IF MORNING ACTIVITY HAMPERS DESTABILIZATION. MIDLEVEL LAPSE RATES ARE NOT TOTALLY IMPRESSIVE AT 6-6.5 K/KM. IF PRECIP HOLDS OFF UNTIL LATER AND SOME MORE RESPECTABLE INSTABILITY DEVELOPS...BULK SHEAR INCREASING TO AROUND 30 KT COULD RESULT IN SOME BETTER ORGANIZED ACTIVITY...BUT CONFIDENCE IS LOW IN THAT SCENARIO. LOCALLY HEAVY RAIN WILL BE POSSIBLE GIVEN THE MOIST ENVIRONMENT...ESPECIALLY IN ANY MORE ORGANIZED ACTIVITY. THE SOUTHWARD PUSH OF THE EAST/WEST ORIENTED COLD FRONT SHOULD SPELL AN END TO MOST POPS AFTER 00Z...THOUGH IT IS NOT A VERY AGRESSIVE FRONTAL PUSH...SO LOW TEMPS TUESDAY NIGHT SHOULD REMAIN IN THE 60S. LOWER THETA-E AIR WILL CONTINUE TO FILTER IN ON WEDNESDAY AS SURFACE ANTICYCLONE OVER ONTARIO ATTEMPTS TO EXPAND SOUTHWARD INTO LOWER MI. THIS WILL BE COMPLICATED BY THE PASSAGE OF A MIDLEVEL SHORTWAVE DURING THE DAY. MODEL SOUNDINGS SHOW A DECIDED LACK OF MIDLEVEL MOISTURE HOWEVER...SO KEPT THE FORECAST DRY. GFS IS SHOWING MOISTURE TRAPPED UNDER AN INVERSION AROUND 900MB FOR MOST OF THE DAY...SO HAVE KEPT A DECENT AMOUNT OF CLOUD COVER AROUND UNTIL THE AFTERNOON. HIGHS WILL BE A BIT COOLER THAN TUESDAY IN THE MID-70S TO NEAR 80. THE HIGH WILL HAVE MORE SUCCESS BUILDING IN WEDNESDAY NIGHT AS DRIER AIR CONTINUES TO FILTER IN...SO EXPECTING CLEARING SKIES AND LOWS MAINLY IN THE 50S. HIGH PRESSURE BUILDS SOUTHWARD INTO THE GREAT LAKES ON THURSDAY AND WILL SLOWLY DRIFT EASTWARD THROUGH FRIDAY. THIS HIGH WILL ALLOW DRY CONDITIONS TO STICK AROUND FOR THE END OF THE WEEK BEFORE A LOW PRESSURE SYSTEM MOVES NORTHWARD TOWARDS SOUTHEAST MICHIGAN LATE SATURDAY AND INTO SUNDAY. THE LOW WILL BRING RAIN SHOWERS AND POSSIBLY THUNDERSTORMS TO THE AREA THROUGH THE FIRST PART OF NEXT WEEK. HIGH TEMPERATURES ARE EXPECTED TO REMAIN STEADY THROUGH THE END OF THE WEEK IN THE MID TO UPPER 70S BEFORE RISING INTO THE LOW TO MID 80S FOR THE WEEKEND. LOW TEMPERATURES WILL REMAIN STEADY IN THE LOW TO MID 60S THROUGH THE EXTENDED PERIOD. MARINE... ACTIVE STRETCH OF WEATHER WILL PERSIST INTO MID WEEK FOR THE EASTERN GREAT LAKES AS A PAIR OF FRONTS WORK THROUGH THE AREA. THE FIRST FRONT IS DRAPED ALONG A LINE FROM LAKE ONTARIO AND LAKE ERIE...SOUTHWEST INTO THE OHIO VALLEY AND WILL PRODUCE SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. THIS WILL VEER WINDS FROM SOUTHERLY TO WESTERLY. A SECOND COLD FRONT WILL DROP SOUTHWARD OUT OF CANADA THROUGH THE EASTERN LAKES TUESDAY AND WEDNESDAY AND WILL USHER NORTHERLY WINDS DOWN THROUGH LAKE HURON. A WEAK PRESSURE GRADIENT WILL KEEP WINDS LIGHT THROUGH THE PERIOD...GENERALLY LESS THAN 15 KNOTS...WHICH IN TURN WILL KEEP THE WAVES IN CHECK. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....DG SHORT TERM...JVC LONG TERM....DRK/RK MARINE.......DRK YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
722 PM EDT MON JUN 23 2014 .AVIATION... //DISCUSSION... SHRAS/TSRAS WILL SPREAD INTO TERMINALS ALONG WARM FRONT LIFTING INTO AREA. COVERAGE WILL BE GREATEST ALONG AND /NORTH OF WARM FRONT FROM PTK ON NORTH. MVFR TO OCCASIONAL IFR CONDITIONS WILL ACCOMPANY THIS CONVECTION. SCATTERED ADDITIONAL ACTIVITY WILL LINGER OVERNIGHT WITH SOUTHERN SHORTWAVE THEN BRING ANOTHER SHOT OF WIDESPREAD SHRAS/TSRAS MID MORNING TO EARLY AFTERNOON TUESDAY. FOR DTW...SCT/BKN LINE OF CONVECTION WILL WEAKEN AS IT MOVES INTO THE AREA BETWEEN 02Z-03Z...BUT TSRAS WILL STILL BE POSSIBLE FOR A FEW HOURS LATE THIS EVENING.ADDITIONAL SHRAS WILL PERCOLATE DURING THE NIGHT BEFORE NEXT SIGNIFICANT BATCH OF RAIN TUESDAY MORNING. CONFIDENCE IS LOW ON THE TIMING OF THIS SECOND IMPULSE. //DTW THRESHOLD THREATS... * MEDIUM CONFIDENCE IN CEILINGS BELOW 5KFT * LOW CONFIDENCE IN TSTORMS AFFECTING KDTW && .PREV DISCUSSION...ISSUED 349 PM EDT MON JUN 23 2014 SHORT TERM...THIS AFTERNOON AND TONIGHT AT 19Z THE SURFACE WARM FRONT WAS DRAPED ROUGHLY ALONG THE MICHIGAN STATE BORDER PER REGIONAL OBSERVATIONS. NORTH OF THE FRONT, SHOWERS ASSOCIATED WITH THIS MORNING`S MCV CONTINUE EXITING EAST. THIS LIGHT PRECIP AND ASSOCIATED CLOUD COVER HAS KEPT TEMPERATURES CONFINED TO THE LOW/MID 70S THROUGH MID-AFTERNOON. SOUTH OF THE WARM FRONT, TEMPERATURES IN THE MID 80S AND DEWPOINTS NEAR 70 ARE CONTRIBUTING TO A MODERATE TO STRONGLY UNSTABLE ENVIRONMENT CHARACTERIZED BY A WEAK/UNIDIRECTIONAL AMBIENT WIND FIELD. WITHIN SAID WARM SECTOR, WIDESPREAD MULTICELL CONVECTION IS ONGOING WITH ONLY ISOLATED SEVERE REPORTS THUS FAR. HOWEVER, SUFFICIENT BOUNDARY LAYER RECOVERY SOUTH OF THE WARM FRONT, MOST LIKELY SOUTH OF I-94, WILL HAVE THE POTENTIAL TO CONTRIBUTE TO A WELL-MIXED ENVIRONMENT THROUGH THE LOWEST 5KFT PER THE LATEST RAP FORECAST SOUNDINGS. THIS, IN THE PRESENCE OF LOCALLY ENHANCED SHEAR INVOF THE WARM FRONT, WILL PRESENT A LOW-END CHANCE FOR BRIEF ORGANIZED UPDRAFTS CAPABLE OF PRODUCING A MARGINAL DIABATICALLY-INDUCED SEVERE WIND THREAT UNTIL DIURNAL HEATING IS LOST LATER THIS EVENING. THUNDERSTORM POTENTIAL WILL PERSIST THROUGH THE NIGHT AS THE AREA BECOMES INCREASINGLY ENTRENCHED IN THE WARM SECTOR. ONE LINE OF THUNDERSTORMS HAS DEVELOPED ALONG A LINE FROM SOUTH BEND TO TERRE HAUTE ALONG THE LEAD EDGE OF THE MID-LEVEL MOISTURE TRANSPORT AXIS. IN ADDITION, MORE UPSTREAM DEVELOPMENT HAS BEGUN JUST SOUTH OF CHICAGO IN ASSOCIATION WITH AN MCV EVIDENT IN AFTERNOON VISIBLE IMAGERY. THIS ACTIVITY WILL SPREAD EAST THROUGH MIDNIGHT, WITH THE LAST ROUND LIKELY AFFECTING THE METRO AREA SOMETIME AROUND 02-03Z. THE PRIMARY THREATS WITH LATE EVENING/EARLY NIGHT ACTIVITY WILL BE HEAVY RAIN DUE TO POTENTIAL TRAINING AND PWATS OF 1.6" TO 1.8" ALONG WITH LIGHTNING. SEVERE WIND POTENTIAL WILL DIMINISH WITH TIME AS THE SUN ANGLE DECREASES. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL REMAIN POSSIBLE THROUGH TONIGHT AS THE MID-LEVEL THERMAL GRADIENT RESPONDS TO AN ENCROACHING NORTHERN STREAM WAVE. THE AGEOSTROPHIC RESPONSE SHOULD BE JUST ENOUGH TO KEEP ACTIVITY BUBBLING WITHIN THE MOISTURE AXIS THROUGH THE NOCTURNAL PERIOD. LOWS IN THE WARM SECTOR WILL STRUGGLE TO FALL BELOW 70 DEGREES. LONG TERM...TUESDAY THROUGH SUNDAY GENERALLY ILL-DEFINED FORCING IN A MOIST ENVIRONMENT /PW 1.5-2 INCHES/ POSES CHALLENGES FOR DETERMINING POPS TUESDAY...BUT TRIED TO KEY IN ON SOME FEATURES WITH THIS PACKAGE. WEAK SURFACE CIRCULATION WILL BE LOCATED NEAR CENTRAL LAKE HURON AT 12Z TUESDAY AND MOVING NORTHEAST...LIKELY ACCOMPANIED BY AN AREA OF SHOWERS/T-STORMS. A WEAK SURFACE TROUGH WILL EXTEND SOUTHWARD FROM THIS LOW...BISECTING LOWER MICHIGAN. MEANWHILE...A SHORTWAVE CURRENTLY NOTED ON WATER VAPOR OVER OKLAHOMA WILL PROGRESS NORTHEASTWARD...REACHING IN/OH BY 00Z WEDNESDAY. WEAK AREA OF MIDLEVEL DEFORMATION NORTH OF THIS WAVE MAY PROVIDE SOME LIFT OVER SE MI...ALONG WITH RIGHT ENTRANCE REGION FORCING FROM 70KT JET OVER NORTHERN LOWER. HAVE HIGHLIGHTED THIS FORCING BY UPGRADING THE SOUTHEAST THIRD OF THE CWA TO ENTRY-LEVEL LIKELY POPS FROM 15-21Z. ALSO LOWERED HIGHS A COUPLE DEGREES OVER THE SOUTH TO ACCOUNT FOR EXPECTED ACTIVITY. OTHERWISE...SHOWER/STORM ACTIVITY IS POSSIBLE IN THE MORNING ALONG THE SURFACE TROUGH. SEVERE POTENTIAL DOES NOT LOOK TOO OVERWHELMING...ESPECIALLY IF MORNING ACTIVITY HAMPERS DESTABILIZATION. MIDLEVEL LAPSE RATES ARE NOT TOTALLY IMPRESSIVE AT 6-6.5 K/KM. IF PRECIP HOLDS OFF UNTIL LATER AND SOME MORE RESPECTABLE INSTABILITY DEVELOPS...BULK SHEAR INCREASING TO AROUND 30 KT COULD RESULT IN SOME BETTER ORGANIZED ACTIVITY...BUT CONFIDENCE IS LOW IN THAT SCENARIO. LOCALLY HEAVY RAIN WILL BE POSSIBLE GIVEN THE MOIST ENVIRONMENT...ESPECIALLY IN ANY MORE ORGANIZED ACTIVITY. THE SOUTHWARD PUSH OF THE EAST/WEST ORIENTED COLD FRONT SHOULD SPELL AN END TO MOST POPS AFTER 00Z...THOUGH IT IS NOT A VERY AGRESSIVE FRONTAL PUSH...SO LOW TEMPS TUESDAY NIGHT SHOULD REMAIN IN THE 60S. LOWER THETA-E AIR WILL CONTINUE TO FILTER IN ON WEDNESDAY AS SURFACE ANTICYCLONE OVER ONTARIO ATTEMPTS TO EXPAND SOUTHWARD INTO LOWER MI. THIS WILL BE COMPLICATED BY THE PASSAGE OF A MIDLEVEL SHORTWAVE DURING THE DAY. MODEL SOUNDINGS SHOW A DECIDED LACK OF MIDLEVEL MOISTURE HOWEVER...SO KEPT THE FORECAST DRY. GFS IS SHOWING MOISTURE TRAPPED UNDER AN INVERSION AROUND 900MB FOR MOST OF THE DAY...SO HAVE KEPT A DECENT AMOUNT OF CLOUD COVER AROUND UNTIL THE AFTERNOON. HIGHS WILL BE A BIT COOLER THAN TUESDAY IN THE MID-70S TO NEAR 80. THE HIGH WILL HAVE MORE SUCCESS BUILDING IN WEDNESDAY NIGHT AS DRIER AIR CONTINUES TO FILTER IN...SO EXPECTING CLEARING SKIES AND LOWS MAINLY IN THE 50S. HIGH PRESSURE BUILDS SOUTHWARD INTO THE GREAT LAKES ON THURSDAY AND WILL SLOWLY DRIFT EASTWARD THROUGH FRIDAY. THIS HIGH WILL ALLOW DRY CONDITIONS TO STICK AROUND FOR THE END OF THE WEEK BEFORE A LOW PRESSURE SYSTEM MOVES NORTHWARD TOWARDS SOUTHEAST MICHIGAN LATE SATURDAY AND INTO SUNDAY. THE LOW WILL BRING RAIN SHOWERS AND POSSIBLY THUNDERSTORMS TO THE AREA THROUGH THE FIRST PART OF NEXT WEEK. HIGH TEMPERATURES ARE EXPECTED TO REMAIN STEADY THROUGH THE END OF THE WEEK IN THE MID TO UPPER 70S BEFORE RISING INTO THE LOW TO MID 80S FOR THE WEEKEND. LOW TEMPERATURES WILL REMAIN STEADY IN THE LOW TO MID 60S THROUGH THE EXTENDED PERIOD. MARINE... ACTIVE STRETCH OF WEATHER WILL PERSIST INTO MID WEEK FOR THE EASTERN GREAT LAKES AS A PAIR OF FRONTS WORK THROUGH THE AREA. THE FIRST FRONT IS DRAPED ALONG A LINE FROM LAKE ONTARIO AND LAKE ERIE...SOUTHWEST INTO THE OHIO VALLEY AND WILL PRODUCE SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. THIS WILL VEER WINDS FROM SOUTHERLY TO WESTERLY. A SECOND COLD FRONT WILL DROP SOUTHWARD OUT OF CANADA THROUGH THE EASTERN LAKES TUESDAY AND WEDNESDAY AND WILL USHER NORTHERLY WINDS DOWN THROUGH LAKE HURON. A WEAK PRESSURE GRADIENT WILL KEEP WINDS LIGHT THROUGH THE PERIOD...GENERALLY LESS THAN 15 KNOTS...WHICH IN TURN WILL KEEP THE WAVES IN CHECK. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....DG SHORT TERM...JVC LONG TERM....DRK/RK MARINE.......DRK YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS GAYLORD MI
145 PM EDT SUN JUN 22 2014 .SYNOPSIS... ISSUED AT 314 AM EDT SUN JUN 22 2014 NORTHERN MICHIGAN WILL REMAIN BETWEEN HIGH PRESSURE SINKING INTO THE EASTERN GREAT LAKES TODAY...AND LOW PRESSURE OVER THE UPPER MISSISSIPPI VALLEY. THERE WILL BE A FEW SHOWERS THIS MORNING...BUT A BETTER SHOT OF SHOWERS AND THUNDERSTORMS...WILL ARRIVE LATER MONDAY AND MONDAY NIGHT. && .UPDATE... ISSUED AT 1100 AM EDT SUN JUN 22 2014 AS REFERENCED IN THE EARLY MORNING DISCUSSION...ONE OF THE MAIN FORECAST QUESTIONS FOR THIS AFTERNOON /IN AN OTHERWISE NEBULOUS WEATHER REGIME/ IS WHETHER A FEW SHOWERS CAN POP THIS AFTERNOON OVER INLAND AREAS OF NRN LOWER. LARGE SCALE FORCING FOR ASCENT REMAINS WEAK...WITH H5 RIDGING OVERHEAD AND LOWER LEVEL WEAK H8 THETA-E ADVECTION. MEANWHILE... SURFACE PRESSURE PATTERN IS VERY WEAK/NONDESCRIPT. THIS WILL ALLOW LAKE BREEZES TO EVOLVE WITH DAYTIME HEATING...WITH GENERAL CONVERGENCE OVER INTERIOR /HIGHER TERRAIN/ AREAS. THOUGH 12Z APX SOUNDING SHOWED A WEAK CAP NEAR H6 /BASED ON LIFTING A 76/56 PARCEL/ AM INCLINED TO INCLUDE ISOLATED LIGHT SHOWERS AFTER 18Z FOR INTERIOR AREAS. DECISION BASED IN LARGE PART ON MORNING VISIBLE SATELLITE TRENDS...WHICH SHOWS PERSISTENT LOW CLOUDS OVER NW LOWER FROM TVC-FKS-MBL...MID CLOUDS OVER NE LOWER...AND RELATIVELY SUNNY SKIES ALONG THE US-131/US-127 CORRIDORS. THIS LATE MORNING DIFFERENTIAL HEATING REGIME /ALREADY SHOWN IN SURFACE WINDS/ MAY BE JUST ENOUGH TO TIP SCALES IN FAVOR OF A FEW SHOWERS. ONLY A 20 PERCENT CHANCE...AND ANY SHOWER THAT DEVELOPS SHOULD BE BRIEF...THOUGH CELLS WILL BE SLOW MOVING. OTHERWISE...A PARTLY SUNNY AFTERNOON IS EXPECTED WITH HIGHS AWAY FROM THE BIG LAKES IN THE 70S. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 314 AM EDT SUN JUN 22 2014 ...SOME SPOTTY SHOWERS THIS MORNING... HIGH IMPACT WEATHER POTENTIAL: PATCHY FOG DEVELOPING AFTER MIDNIGHT SUNDAY NIGHT/MONDAY MORNING. PATTERN SUMMARY/IMPLICATIONS: VERY SIMILAR STORY TO WHAT WE DISCUSSED 24 HOURS AGO WITH CLOSED LOW SITTING OVER MANITOBA/SASKATCHEWAN WITH DOWNSTREAM RIDGING OVER MICHIGAN NORTH INTO ONTARIO SQUEEZED AGAINST LARGER SCALE TROUGHING OVER EASTERN CANADA. SHORTWAVES CONTINUE TO SHEAR OUT AS THEY RUN INTO THE OVERHEAD RIDGE AXIS...WITH THE MOST RECENT WAVE OF DEEP MOISTURE NOW BEGINNING TO PULL EAST OF THE STATE. DRILLING DOWN TO THE SURFACE ALSO REVEALS STRONG SIMILARITY TO ONE DAY AGO WITH HIGH PRESSURE ANCHORED OVER HUDSON BAY AND A SURFACE LOW BENEATH THE CLOSE FEATURE OVER MANITOBA. BETWEEN THESE FEATURES...A PLUME OF DEEPER MOISTURE REMAINS STALLED OVER NORTHERN MICHIGAN. WEAK POSITIVE THETAE ADVECTION AT H8 CONTINUES TO FORCE SHRAS PRIMARILY OVER THE NORTHEASTERN HALF OF THE CWA. GIVEN THE STAGNANT NATURE OF THE PATTERN...FORECAST CHALLENGES WILL CONTINUE TO REVOLVE AROUND LIGHT PRECIPITATION POTENTIAL WITH ASSOCIATED CLOUDS/IMPACTS ON TEMPERATURES. TODAY... PRECIPITATION CHANCES: OVERHEAD H8 THETAE GRADIENT STALLS OVER EASTERN CHIP/MACK SOUTH AND EAST ACROSS NORTHEAST LOWER THROUGH NOON BEFORE BEING PUSHED NORTH AND EAST. WITH DEEP MOISTURE WANING /SEE CURRENT WV IMAGERY/...EXPECT COVERAGE IN SHOWER ACTIVITY ASSOCIATED WITH THIS GRADIENT TO WEAKEN...BUT LIKELY NOT QUIT THROUGH THE MORNING HOURS...WARRANTING A CHANCE POP/SCATTERED WORDING HERE. AS WE LOOK INTO THE AFTERNOON...FOCUS TURNS TO POPPING ANY DIURNAL CONVECTION WITH A SOMEWHAT MOISTER LLEVEL AIRMASS THAN 24 HOURS PREVIOUS. STILL THINK THE NAM IS TOO ROBUST WITH LLEVEL MOISTURE...BUT EVEN THE FAR MORE CONSERVATIVE RAP ALLOWS FOR 500-750 JOULES OF MUCAPE DEVELOPMENT OVER THE HIGH TERRAIN OF INTERIOR NORTHERN LOWER. QG FORCING FOR ASCENT IS NIL OVERHEAD WITH SLOWLY BUILDING HEIGHTS ALOFT REQUIRING LAKE BREEZES/UPSLOPE CONVERGENCE TO PUSH US TO CONVECTIVE INITIATION. HAVE TROUBLE BELIEVING WE CAN GET AROUND MODEST CAPPING NEAR H7 PURELY WITH BOUNDARY LAYER PROCESSES. THUS...WILL MAINTAIN GOING DRY FORECAST FOR THE AFTERNOON HOURS. QPF: BASIN WIDE AMOUNTS VERY LIGHT...LESS THAN 0.05". ISOLATED LOCATIONS COULD RECEIVE NEAR 0.20" GIVEN MODEST PWATS/WARM CLOUD DEPTHS AND LIGHT STEERING FLOW. TEMPERATURES: T8S NEAR +12C AT 00Z WITH CONTINUED SLOW WARMING THROUGH TODAY SUGGESTS WE SHOULD BE ABLE TO BEST YESTERDAYS HIGHS AND GUIDANCE CONSENSUS HANDLES THIS WELL...WITH MID/UPPER 70S INLAND AND CLOSER TO 70 AT THE LAKE-BREEZE COOLED COASTS. WINDS: CONTINUED LIGHT GRADIENT FAVORS ROBUST LAKE BREEZE DEVELOPMENT THIS AFTERNOON. TONIGHT... PRECIPITATION CHANCES: WITH NO HELPFUL LLEVEL MOISTURE ADVECTION...CHANCES WILL BE CONTINGENT ON AFTERNOON ACTIVITY PERSISTING INTO THE EVENING. GIVEN THE CURRENT EXPECTATION THAT WE/LL REMAIN SHOWER FREE THROUGH THE AFTERNOON...WILL MAINTAIN DRY CONDITIONS THROUGH THE TONIGHT PERIOD AS WELL. QPF: NIL. TEMPERATURES: WILL STICK NEAR GUIDANCE CONSENSUS IN THE MID 50S AS PARTLY CLOUDY SKIES SHOULD ALLOW FOR MODEST RADIATIONAL COOLING WITH GEOSTROPHIC FLOW AT 1000MB NEAR 10KTS LIKELY STILL ALLOW MOST LOCATIONS TO DECOUPLE. WINDS: CALM OR LIGHT DRAINAGE FLOWS EXPECTED. FOG: WITH MID/UPPER LEVEL MOISTURE BEGINNING TO PULL EAST...CAN SEE SOME INCREASED FOG POTENTIAL AS LLEVEL FLOW GAINS A SOUTHWESTERLY COMPONENT WITH CONTINUED WEAK LLEVEL MOISTURE ADVECTION AND ENOUGH CLEARING FOR RADIATIONAL COOLING IN THE PRESENCE OF ELEVATED 2M DEWPOINTS. WILL ADD PATCHY FOG TO THE FORECAST AFTER MIDNIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 314 AM EDT SUN JUN 22 2014 ...SCATTERED THUNDERSTORMS MONDAY AND MONDAY NIGHT... IMPACTS: MINIMAL. SEVERE STORMS STILL LOOK UNLIKELY. SYNOPTIC PATTERN/EVOLUTION: THE ENTIRE FORECAST PERIOD OF MONDAY THROUGH THE NEXT WEEKEND WILL SEE A SHALLOW AND PROGRESSIVE MID LEVEL AMPLITUDE PATTERN THROUGH A GOOD CHUNK OF THE WORK WEEK. THEN...HEIGHTS RISE OVER THE HEART OF THE COUNTRY...INCLUDING THE WESTERN GREAT LAKES. THIS IS IN RESPONSE TO TWO LARGE UPPER/CLOSED LOWS DROPPING INTO THE PAC NW/NEW ENGLAND. AN INCREASINGLY MUGGIER AIR MASS MONDAY AND EARLY TUESDAY...AHEAD OF AN APPROACHING AREA OF LOW PRESSURE AND PRECIPITATION...WILL GET COOLED AND DRIED DOWN LATER TUESDAY THROUGH WEDNESDAY. TEMPERATURES WILL START RISING BACK UP AGAIN FOR LATE IN THE WORK WEEK. PRECIPITATION CHANCES AFTER EARLY TUESDAY DO NOT LOOK ALL THAT FANTASTIC. MON-TUES: THE BEST ACTION RESIDES IN THIS TIME FRAME. SHALLOW RIDGING EXITS EAST...WHILE AN ELONGATED UPPER TROUGH AXIS ACROSS ONTARIO BACKS WINDS ALOFT WSW. SHORTWAVE ENERGY AND AN ASSOCIATED SFC LOW WILL LIFT UP ACROSS NRN MICHIGAN. THIS LOW PRESSURE DOESN`T LOOK ALL THAT IMPRESSIVE...BUT A WARM FRONT WILL EDGE UP THROUGH MUCH OF NRN LOWER...WITH THE TRAILING COLD FRONT EXITING NEAR TUESDAY MORNING. AS THE SFC LOW DEPARTS...ANOTHER COLD FRONT...ONE WITH MORE REFRESHING AIR...WILL SLIDE SOUTHWARD THROUGH NRN MICHIGAN BY OVER NIGHT TUESDAY NIGHT (UNCERTAINTY ON EXACT TIMING). COULD SEE SOME SHOWERS POSSIBLY SNEAKING INTO A FEW SECTIONS OF NW LOWER MONDAY MORNING...AND ALSO SOME POTENTIAL CONVECTIVE DEBRIS FROM FURTHER WEST...BUT THE USING AN EXPECTED AVERAGE PARCEL OF 80/61 (DEW POINT IS SOME QUESTION)...CAN POSSIBLY GLEAN 1000-1300 J/KG MONDAY LATE AFTERNOON. RIGHT WITH THE WARM FRONTAL ARRIVAL. THE LOW TRACKS OVER NRN MICHIGAN WITH MAINLY NRN LOWER SNEAKING INTO THE WARM SECTOR FOR THE EVENING (TIMING ALSO IN SOME QUESTION). SHOWER AND STORM CHANCES WILL BE GREATEST MONDAY NIGHT...AND ALTHOUGH NOTHING OVERLY IMPRESSIVE...WILL HAVE TO WATCH THE DEVELOPMENTS SURROUNDING WIND FIELDS AND INSTABILITY. THERE IS A TIGHTENING IN THE MID LEVEL FLOW (40KTS)...AND IF THE INSTABILITY ABOVE CAN BE HAD...AND BEING IN THE WARM SECTOR...WHILE EASTERN UPPER GETS GARDEN VARIETY SHOWERS AND A FEW STORMS...NRN LOWER COULD SEE STRONGER CELLS. CELLS THAT WILL BE IN A BETTER ENVIRONMENT FOR GUSTY WINDS/SMALLISH HAIL AND THE POSSIBILITY OF A ROGUE TORNADO. THAT`S AN AWFUL LOT OF IF`S THOUGH. AFTER THE LOW DEPARTS...AND SECONDARY COOL FRONT GETS DROPPED THROUGH US...WITH MINIMAL FORCING...DIMINISHING MOISTURE AND A TOTAL LACK OF INSTABILITY DUE TO MORE OF A COL AREA IN STORE FOR US. HIGHS WELL INTO THE 70S MONDAY WILL START COOLING OFF...WITH HIGHS TUESDAY IN THE UPPER 60S/70F IN EASTERN UPPER...AND UPPER 70S NEARER SAGINAW BAY. WEDNESDAY THROUGH NEXT WEEKEND: AN EVEN COOLER DAY WEDNESDAY WITH HIGHS IN THE MAINLY IN THE 60S...A FEW LOWER 70S...AS HIGH PRESSURE SLIPS INTO OUR NECK OF THE WOODS FROM ONTARIO. SHOULD BE A BEAUTIFUL DAY. THERE ARE DEFINITE HINTS AT SOME SHORTWAVE ACTIVITY TRACKING THROUGH US THURSDAY/THURSDAY NIGHT FOR RAIN SHOWER CHANCES...BEFORE MID LEVEL HEIGHTS RISES BEGIN FRIDAY AND CONTINUE INTO THE WEEKEND FOR A RETURN TO MIDDLE 70S TO LOWER 80S TEMPS. EARLY HINTS ARE FOR NO PRECIPITATION NEXT WEEKEND WITH ALL THE HEAT AND INSTABILITY RESIDING TO OUR WEST AND SOUTH. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 139 PM EDT SUN JUN 22 2014 WEAK HIGH PRESSURE OVER THE ERN GREAT LAKES WILL PROVIDE NRN MI WITH CONTINUED VFR WEATHER CONDITIONS THIS AFTERNOON INTO THIS EVENING...WITH ONLY SCATTERED CU AND PATCHES OF MID LEVEL AC EXPECTED. WINDS WILL REMAIN LIGHT...WITH GENERAL ONSHORE LAKE BREEZES ANTICIAPTED. SOME PATCHY IFR/MVFR FOG WILL DEVELOP AFTER MIDNIGHT TONIGHT WITH LIGHT WINDS...PARTLY CLOUDY SKIES...AND INCREASING LOW LEVEL MOISTURE. THE NEXT RISK FOR SHOWERS AND STORMS WILL ARRIVE BEGINNING MONDAY AFTERNOON. && .MARINE... ISSUED AT 314 AM EDT SUN JUN 22 2014 SUMMARY: HIGH PRESSURE OVER HUDSON BAY WILL MOVE SOUTH AND EAST OFF THE ATLANTIC COAST THROUGH MONDAY ALLOWING AN AREA OF LOW PRESSURE TO MOVE INTO THE GREAT LAKES REGION FOR MONDAY NIGHT AND TUESDAY. HIGH PRESSURE BUILDS INTO THE REGION BEHIND THIS LOW FOR WEDNESDAY AND THURSDAY. HEADLINES: WINDS AND WAVES WILL REMAIN BELOW SMALL CRAFT LEVELS THROUGH MONDAY NIGHT. THERE IS SOME POTENTIAL FOR SMALL CRAFT LEVEL WINDS UNDER NORTHWEST WINDS TUESDAY/TUESDAY NIGHT AS LOW PRESSURE DEPARTS THE REGION TO THE EAST. AS LOW PRESSURE PULLS EAST OF THE REGION HIGH PRESSURE BUILDS IN FOR THE WEDNESDAY-FRIDAY TIMEFRAME WITH HEADLINE FREE CONDITIONS EXPECTED. THUNDERSTORMS: CHANCES FOR STORMS INCREASE ON MONDAY WITH A PERIOD OF THUNDERSTORMS LIKELY TUESDAY/TUESDAY NIGHT. WIDESPREAD SEVERE THREAT IS LOW...BUT ISOLATED STRONG TO SEVERE STORMS ARE POSSIBLE. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...NONE. LM...NONE. LS...NONE. && $$ UPDATE...SMITH SYNOPSIS...SMD SHORT TERM...ARNOTT LONG TERM...SMD AVIATION...BS MARINE...ARNOTT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
115 PM EDT SUN JUN 22 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 523 AM EDT SUN JUN 22 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER CNTRL SASK/MANITOBA AND A DOWNSTREAM RIDGE FROM THE NRN LAKES TO JAMES BAY. AT THE SFC...TROUGH EXTENDED INTO THE ERN DAKOTAS AND CNTRL NEBRASKA FROM LOW PRES NEAR LAKE WINNIPEG WHILE HIGH PRES PREVAILED TO THE EAST FROM SRN QUEBEC INTO THE NRN LAKES. A SHRTWV TROUGH AHEAD OF THE MID LEVEL LOW SUPPORTED SOME SHRA/TSRA FROM NW ONTARIO TO NEAR KELO. HOWEVER...THE STRONGER AND MORE WIDEPSREAD CONVECTION WAS WELL TO THE SOUTH FROM ERN NEBRASKA INTO WRN IA WHERE THE MORE FAVORABLE INSTABIILITY (MUCPAE TO NEAR 2K J/KG) AND MOISTURE TRANSPORT WAS LOCATED. OTHERWISE...MAINLY LOW STRATUS PREVAILED ACROSS MUCH OF WEST AND CENTRAL UPPER MI WHERE LOW LEVEL MOISTURE REMAINS BELOW THE 925 MB INVERSION. TODAY...EXPECT THAT THE SHRA/TSRA ASSOCIATED WITH THE MODEST FORCING ASSOCIATED WITH THE NW ONTARIO SHRTWV WILL WEAKEN AS IT MOVES TOWARD THE RIDGE. DAYTIME HEATING SHOULD BREAK UP THE LOWER CLOUDS SO THAT AFTERNOON SUNSHINE WILL PUSH TEMPS INTO THE LOWER 80S INLAND WHILE LAKE BREEZES LIMIT READINGS TO THE 60S NEAR THE GREAT LAKES. THE NAM AND SEVERAL HIGHER RES MODELS SUGGEST THAT THERE WILL BE ENOUGH INSTABILITY FOR SOME SHRA/TSRA OVER MAINLY THE WEST THIRD DURING THE AFTERNOON. HOWEVER...SINCE MORE MODEST MLCAPE VALUES INTO THE 300-600 J/KG RANGE ARE EXPECTED AND LARGE SCALE FORCING IS NOT FCST...CONFIDENCE FOR SHRA/TSRA DEVELOPMENT IS LOW AND ONLY SLIGHT CHANCE POPS WERE INCLUDED. TONIGHT...ANY CONVECTION THAT DEVELOPS DURING THE AFTERNOON WILL DIMINISH DURING THE EVENING. HOWEVER...AS THE TROUGH AND FRONTAL BOUNDARY EDGE TOWARD THE WRN CWA OVERNIGHT...SHRA/TSRA CHANCES WILL INCREASE AS ADDITIONAL WEAK SHORTWAVES EMERGE FROM THE PLAINS. THERE IS LESS CONFIDENCE IN THE EASTWARD EXTENT OF THE PCPN AS THE RIDGE TO THE EAST LIMITS THE MOVEMENT OF THE MOISTURE AXIS TO THE EAST. IN ADDITION...ANOTHER ROUND OF STRONGER CONVECTION IS MORE LIKELY OVER NRN IA OR SRN MN INTO SRN WI THAT WOULD LIMIT MOISTURE TRANSPORT TO THE NORTH. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 509 AM EDT SUN JUN 22 2014 MONDAY CONTINUES TO LOOK LIKE A SHOWERY DAY ACROSS MUCH OF THE WESTERN HALF OF UPPER MICHIGAN AS THE UPPER LOW OVER MANITOBA/SASKATCHEWAN FINALLY OPENS UP AND SLOWLY MOVES EASTWARD. MEANWHILE...A WEAK UPPER SHORT WAVE OVER THE CENTRAL PLAINS MOVES TOWARD THE REGION. THESE TWO FEATURES WILL WILL ALLOW FOR WEAK LOW PRESSURE TO DEVELOP OVER THE MID MS VLY AND MOVE TOWARD THE GREAT LAKES. MOISTURE AND WARM ADVECTION AHEAD OF THE TROUGH WILL SPREAD ACROSS THE AREA MONDAY AND BE SLOW TO MOVE OUT UNTIL THE LOW PASSES BY TUE. EXPECT SHOWERS AND ISOLATED STORMS TO DEVELOP ACROSS THE WESTERN U.P. MON MORNING THEN SLOWLY SPREAD EASTWARD DURING THE DAY AS THE 850MB TROUGH AND ASSOCIATED MOISTURE CONVERGENCE MOVES EAST. WITH THE COMBINATION OF THE FAVORABLE DYNAMICS FROM THE SHORT WAVE ENERGY AS WELL AS HIGH MOISTURE CONTENT OF THE ATMOSPHERE /PRECIPITABLE WATER VALUES AROUND 1.75 INCHES/...EXPECT A FEW AREAS ACROSS THE WEST HALF TO SEE 0.50 TO 1.0 INCHES OF RAIN MONDAY UNDER THE HEAVIEST AND MOST PERSISTENT SHOWER ACTIVITY. AS SUCH...WILL KEEP LIKELY POPS ACROSS THE ENTIRE WESTERN HALF OF THE FORECAST AREA ON MONDAY. FUTURE SHIFTS WILL LIKELY NEED TO RAISE POPS MORE...BUT THERE IS STILL SOME UNCERTAINTY EXACTLY WHERE THE BEST RAIN WILL SET UP. AS THE LOW MOVES SOUTH OF THE AREA MONDAY NIGHT...THE COLD FRONT ASSOCIATED WITH THE NORTHERN STREAM ENERGY WILL DIVE SOUTHWARD. MOISTURE WILL PERSIST ACROSS MUCH OF THE EASTERN HALF OF UPPER MICHIGAN MONDAY NIGHT COMBINED WITH SYNOPTIC FORCING FROM THE UPPER TROUGH. AS SUCH...WILL MAINTAIN LIKELY POPS EAST FOR MONDAY NIGHT TAPERING TO CHANCE POPS FOR THE WEST. TUESDAY MAY END UP BEING A FAIRLY RAW DAY ACROSS AT LEAST THE NORTHERN HALF OF UPPER MI WITH NORTHERLY FLOW BEHIND THE LOW COMBINED WITH SCATTERED SHOWERS DUE TO THE CONTINUE 850MB BAROCLINIC ZONE ACROSS THE AREA AND DEEP MOISTURE. WILL MAINTAIN CHANCE POPS ACROSS THE ENTIRE AREA ALTHOUGH CLOSER TO LAKE SUPERIOR MAY SEE MORE DRIZZLE THAN ANYTHING. AREAS CLOSE TO LAKE SUPERIOR MAY STRUGGLE TO RISE OUT OF THE MID 50S ON TUESDAY ALTHOUGH INLAND AREAS WILL SEE TEMPS RISE WELL INTO THE 60S. FOR TUE NIGHT/WED...HIGH PRESSURE BUILDS ACROSS THE AREA LEADING TO A DRY PERIOD THROUGH WED NIGHT. HIGH PRESSURE HANGS ON THRU THU ALTHOUGH THE ECMWF AND GFS BOTH SUGGEST ANOTHER SHORT WAVE MOVING INTO THE UPPER LAKES DURING THE DAY WHICH MAY ALLOW FOR SHOWERS AND ISOLATED STORMS DURING THE AFTERNOON. UPPER RIDGING FINALLY BUILDS IN FOR THE WEEKEND WHICH MEANS TEMPERATURES RISING TO ABOVE NORMAL. MAY BE A CHANCE FOR RAIN FRI NIGHT INTO SATURDAY AS WEAK WARM ADVECTION DEVELOPS...BUT LATEST ECMWF SUGGESTS THAT THE RAIN CHANCES WILL HOLD OFF UNTIL SAT NIGHT/SUN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 115 PM EDT SUN JUN 22 2014 MORE FOG AND LOW CLOUDS COULD ROLL IN OFF LAKE SUPERIOR THIS EVENING AT CMX. A FEW SHOWERS ARE POSSIBLE LATE TONIGHT AT CMX AND IWD BUT ARE NOT EXPECTED TO REDUCE CONDITIONS BELOW VFR AT IWD AND THE FOG WILL PRODUCE MVFR CONDITIONS AT CMX. UPSLOPE FOG WILL FORM AT SAW OFF LAKE MICHIGAN TONIGHT WITH SOUTH TO SOUTHEAST WINDS...THEN AS WINDS GO TO THE SW LATE...THE FOG WILL DISSIPATE. VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD AT SAW AND IWD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 523 AM EDT SUN JUN 22 2014 DENSE FOG WILL CONTINUE TO BE THE MAIN CONCERN ACROSS WEST AND CENTRAL LAKE SUPERIOR. LINGERING LOW LEVEL MOISTURE WITH PERSISTENT LIGHT E OR SE LOW LEVEL FLOW WILL ALLOW FOR DENSE FOG WILL HELP TO MAINTAIN THE FOG OR LOW STRATUS TODAY. THERE MAY BE ENOUGH DRY AIR MOVING IN THIS AFTERNOON TO MIX OUT THE FOG BUT THERE IS THE POSSIBILITY THAT AN EXTENSION OF THE DENSE FOG ADVISORY MAY BE NEEDED. WINDS WILL REMAIN AT OR BELOW 20 KNOTS THROUGH THIS FORECAST PERIOD. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... DENSE FOG ADVISORY UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON FOR LSZ162-240>248-263>265. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...MRD AVIATION...07 MARINE...JLB
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1123 AM EDT SUN JUN 22 2014 .SYNOPSIS... ISSUED AT 314 AM EDT SUN JUN 22 2014 NORTHERN MICHIGAN WILL REMAIN BETWEEN HIGH PRESSURE SINKING INTO THE EASTERN GREAT LAKES TODAY...AND LOW PRESSURE OVER THE UPPER MISSISSIPPI VALLEY. THERE WILL BE A FEW SHOWERS THIS MORNING...BUT A BETTER SHOT OF SHOWERS AND THUNDERSTORMS...WILL ARRIVE LATER MONDAY AND MONDAY NIGHT. && .UPDATE... ISSUED AT 1100 AM EDT SUN JUN 22 2014 AS REFERENCED IN THE EARLY MORNING DISCUSSION...ONE OF THE MAIN FORECAST QUESTIONS FOR THIS AFTERNOON /IN AN OTHERWISE NEBULOUS WEATHER REGIME/ IS WHETHER A FEW SHOWERS CAN POP THIS AFTERNOON OVER INLAND AREAS OF NRN LOWER. LARGE SCALE FORCING FOR ASCENT REMAINS WEAK...WITH H5 RIDGING OVERHEAD AND LOWER LEVEL WEAK H8 THETA-E ADVECTION. MEANWHILE... SURFACE PRESSURE PATTERN IS VERY WEAK/NONDESCRIPT. THIS WILL ALLOW LAKE BREEZES TO EVOLVE WITH DAYTIME HEATING...WITH GENERAL CONVERGENCE OVER INTERIOR /HIGHER TERRAIN/ AREAS. THOUGH 12Z APX SOUNDING SHOWED A WEAK CAP NEAR H6 /BASED ON LIFTING A 76/56 PARCEL/ AM INCLINED TO INCLUDE ISOLATED LIGHT SHOWERS AFTER 18Z FOR INTERIOR AREAS. DECISION BASED IN LARGE PART ON MORNING VISIBLE SATELLITE TRENDS...WHICH SHOWS PERSISTENT LOW CLOUDS OVER NW LOWER FROM TVC-FKS-MBL...MID CLOUDS OVER NE LOWER...AND RELATIVELY SUNNY SKIES ALONG THE US-131/US-127 CORRIDORS. THIS LATE MORNING DIFFERENTIAL HEATING REGIME /ALREADY SHOWN IN SURFACE WINDS/ MAY BE JUST ENOUGH TO TIP SCALES IN FAVOR OF A FEW SHOWERS. ONLY A 20 PERCENT CHANCE...AND ANY SHOWER THAT DEVELOPS SHOULD BE BRIEF...THOUGH CELLS WILL BE SLOW MOVING. OTHERWISE...A PARTLY SUNNY AFTERNOON IS EXPECTED WITH HIGHS AWAY FROM THE BIG LAKES IN THE 70S. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 314 AM EDT SUN JUN 22 2014 ...SOME SPOTTY SHOWERS THIS MORNING... HIGH IMPACT WEATHER POTENTIAL: PATCHY FOG DEVELOPING AFTER MIDNIGHT SUNDAY NIGHT/MONDAY MORNING. PATTERN SUMMARY/IMPLICATIONS: VERY SIMILAR STORY TO WHAT WE DISCUSSED 24 HOURS AGO WITH CLOSED LOW SITTING OVER MANITOBA/SASKATCHEWAN WITH DOWNSTREAM RIDGING OVER MICHIGAN NORTH INTO ONTARIO SQUEEZED AGAINST LARGER SCALE TROUGHING OVER EASTERN CANADA. SHORTWAVES CONTINUE TO SHEAR OUT AS THEY RUN INTO THE OVERHEAD RIDGE AXIS...WITH THE MOST RECENT WAVE OF DEEP MOISTURE NOW BEGINNING TO PULL EAST OF THE STATE. DRILLING DOWN TO THE SURFACE ALSO REVEALS STRONG SIMILARITY TO ONE DAY AGO WITH HIGH PRESSURE ANCHORED OVER HUDSON BAY AND A SURFACE LOW BENEATH THE CLOSE FEATURE OVER MANITOBA. BETWEEN THESE FEATURES...A PLUME OF DEEPER MOISTURE REMAINS STALLED OVER NORTHERN MICHIGAN. WEAK POSITIVE THETAE ADVECTION AT H8 CONTINUES TO FORCE SHRAS PRIMARILY OVER THE NORTHEASTERN HALF OF THE CWA. GIVEN THE STAGNANT NATURE OF THE PATTERN...FORECAST CHALLENGES WILL CONTINUE TO REVOLVE AROUND LIGHT PRECIPITATION POTENTIAL WITH ASSOCIATED CLOUDS/IMPACTS ON TEMPERATURES. TODAY... PRECIPITATION CHANCES: OVERHEAD H8 THETAE GRADIENT STALLS OVER EASTERN CHIP/MACK SOUTH AND EAST ACROSS NORTHEAST LOWER THROUGH NOON BEFORE BEING PUSHED NORTH AND EAST. WITH DEEP MOISTURE WANING /SEE CURRENT WV IMAGERY/...EXPECT COVERAGE IN SHOWER ACTIVITY ASSOCIATED WITH THIS GRADIENT TO WEAKEN...BUT LIKELY NOT QUIT THROUGH THE MORNING HOURS...WARRANTING A CHANCE POP/SCATTERED WORDING HERE. AS WE LOOK INTO THE AFTERNOON...FOCUS TURNS TO POPPING ANY DIURNAL CONVECTION WITH A SOMEWHAT MOISTER LLEVEL AIRMASS THAN 24 HOURS PREVIOUS. STILL THINK THE NAM IS TOO ROBUST WITH LLEVEL MOISTURE...BUT EVEN THE FAR MORE CONSERVATIVE RAP ALLOWS FOR 500-750 JOULES OF MUCAPE DEVELOPMENT OVER THE HIGH TERRAIN OF INTERIOR NORTHERN LOWER. QG FORCING FOR ASCENT IS NIL OVERHEAD WITH SLOWLY BUILDING HEIGHTS ALOFT REQUIRING LAKE BREEZES/UPSLOPE CONVERGENCE TO PUSH US TO CONVECTIVE INITIATION. HAVE TROUBLE BELIEVING WE CAN GET AROUND MODEST CAPPING NEAR H7 PURELY WITH BOUNDARY LAYER PROCESSES. THUS...WILL MAINTAIN GOING DRY FORECAST FOR THE AFTERNOON HOURS. QPF: BASIN WIDE AMOUNTS VERY LIGHT...LESS THAN 0.05". ISOLATED LOCATIONS COULD RECEIVE NEAR 0.20" GIVEN MODEST PWATS/WARM CLOUD DEPTHS AND LIGHT STEERING FLOW. TEMPERATURES: T8S NEAR +12C AT 00Z WITH CONTINUED SLOW WARMING THROUGH TODAY SUGGESTS WE SHOULD BE ABLE TO BEST YESTERDAYS HIGHS AND GUIDANCE CONSENSUS HANDLES THIS WELL...WITH MID/UPPER 70S INLAND AND CLOSER TO 70 AT THE LAKE-BREEZE COOLED COASTS. WINDS: CONTINUED LIGHT GRADIENT FAVORS ROBUST LAKE BREEZE DEVELOPMENT THIS AFTERNOON. TONIGHT... PRECIPITATION CHANCES: WITH NO HELPFUL LLEVEL MOISTURE ADVECTION...CHANCES WILL BE CONTINGENT ON AFTERNOON ACTIVITY PERSISTING INTO THE EVENING. GIVEN THE CURRENT EXPECTATION THAT WE/LL REMAIN SHOWER FREE THROUGH THE AFTERNOON...WILL MAINTAIN DRY CONDITIONS THROUGH THE TONIGHT PERIOD AS WELL. QPF: NIL. TEMPERATURES: WILL STICK NEAR GUIDANCE CONSENSUS IN THE MID 50S AS PARTLY CLOUDY SKIES SHOULD ALLOW FOR MODEST RADIATIONAL COOLING WITH GEOSTROPHIC FLOW AT 1000MB NEAR 10KTS LIKELY STILL ALLOW MOST LOCATIONS TO DECOUPLE. WINDS: CALM OR LIGHT DRAINAGE FLOWS EXPECTED. FOG: WITH MID/UPPER LEVEL MOISTURE BEGINNING TO PULL EAST...CAN SEE SOME INCREASED FOG POTENTIAL AS LLEVEL FLOW GAINS A SOUTHWESTERLY COMPONENT WITH CONTINUED WEAK LLEVEL MOISTURE ADVECTION AND ENOUGH CLEARING FOR RADIATIONAL COOLING IN THE PRESENCE OF ELEVATED 2M DEWPOINTS. WILL ADD PATCHY FOG TO THE FORECAST AFTER MIDNIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 314 AM EDT SUN JUN 22 2014 ...SCATTERED THUNDERSTORMS MONDAY AND MONDAY NIGHT... IMPACTS: MINIMAL. SEVERE STORMS STILL LOOK UNLIKELY. SYNOPTIC PATTERN/EVOLUTION: THE ENTIRE FORECAST PERIOD OF MONDAY THROUGH THE NEXT WEEKEND WILL SEE A SHALLOW AND PROGRESSIVE MID LEVEL AMPLITUDE PATTERN THROUGH A GOOD CHUNK OF THE WORK WEEK. THEN...HEIGHTS RISE OVER THE HEART OF THE COUNTRY...INCLUDING THE WESTERN GREAT LAKES. THIS IS IN RESPONSE TO TWO LARGE UPPER/CLOSED LOWS DROPPING INTO THE PAC NW/NEW ENGLAND. AN INCREASINGLY MUGGIER AIR MASS MONDAY AND EARLY TUESDAY...AHEAD OF AN APPROACHING AREA OF LOW PRESSURE AND PRECIPITATION...WILL GET COOLED AND DRIED DOWN LATER TUESDAY THROUGH WEDNESDAY. TEMPERATURES WILL START RISING BACK UP AGAIN FOR LATE IN THE WORK WEEK. PRECIPITATION CHANCES AFTER EARLY TUESDAY DO NOT LOOK ALL THAT FANTASTIC. MON-TUES: THE BEST ACTION RESIDES IN THIS TIME FRAME. SHALLOW RIDGING EXITS EAST...WHILE AN ELONGATED UPPER TROUGH AXIS ACROSS ONTARIO BACKS WINDS ALOFT WSW. SHORTWAVE ENERGY AND AN ASSOCIATED SFC LOW WILL LIFT UP ACROSS NRN MICHIGAN. THIS LOW PRESSURE DOESN`T LOOK ALL THAT IMPRESSIVE...BUT A WARM FRONT WILL EDGE UP THROUGH MUCH OF NRN LOWER...WITH THE TRAILING COLD FRONT EXITING NEAR TUESDAY MORNING. AS THE SFC LOW DEPARTS...ANOTHER COLD FRONT...ONE WITH MORE REFRESHING AIR...WILL SLIDE SOUTHWARD THROUGH NRN MICHIGAN BY OVER NIGHT TUESDAY NIGHT (UNCERTAINTY ON EXACT TIMING). COULD SEE SOME SHOWERS POSSIBLY SNEAKING INTO A FEW SECTIONS OF NW LOWER MONDAY MORNING...AND ALSO SOME POTENTIAL CONVECTIVE DEBRIS FROM FURTHER WEST...BUT THE USING AN EXPECTED AVERAGE PARCEL OF 80/61 (DEW POINT IS SOME QUESTION)...CAN POSSIBLY GLEAN 1000-1300 J/KG MONDAY LATE AFTERNOON. RIGHT WITH THE WARM FRONTAL ARRIVAL. THE LOW TRACKS OVER NRN MICHIGAN WITH MAINLY NRN LOWER SNEAKING INTO THE WARM SECTOR FOR THE EVENING (TIMING ALSO IN SOME QUESTION). SHOWER AND STORM CHANCES WILL BE GREATEST MONDAY NIGHT...AND ALTHOUGH NOTHING OVERLY IMPRESSIVE...WILL HAVE TO WATCH THE DEVELOPMENTS SURROUNDING WIND FIELDS AND INSTABILITY. THERE IS A TIGHTENING IN THE MID LEVEL FLOW (40KTS)...AND IF THE INSTABILITY ABOVE CAN BE HAD...AND BEING IN THE WARM SECTOR...WHILE EASTERN UPPER GETS GARDEN VARIETY SHOWERS AND A FEW STORMS...NRN LOWER COULD SEE STRONGER CELLS. CELLS THAT WILL BE IN A BETTER ENVIRONMENT FOR GUSTY WINDS/SMALLISH HAIL AND THE POSSIBILITY OF A ROGUE TORNADO. THAT`S AN AWFUL LOT OF IF`S THOUGH. AFTER THE LOW DEPARTS...AND SECONDARY COOL FRONT GETS DROPPED THROUGH US...WITH MINIMAL FORCING...DIMINISHING MOISTURE AND A TOTAL LACK OF INSTABILITY DUE TO MORE OF A COL AREA IN STORE FOR US. HIGHS WELL INTO THE 70S MONDAY WILL START COOLING OFF...WITH HIGHS TUESDAY IN THE UPPER 60S/70F IN EASTERN UPPER...AND UPPER 70S NEARER SAGINAW BAY. WEDNESDAY THROUGH NEXT WEEKEND: AN EVEN COOLER DAY WEDNESDAY WITH HIGHS IN THE MAINLY IN THE 60S...A FEW LOWER 70S...AS HIGH PRESSURE SLIPS INTO OUR NECK OF THE WOODS FROM ONTARIO. SHOULD BE A BEAUTIFUL DAY. THERE ARE DEFINITE HINTS AT SOME SHORTWAVE ACTIVITY TRACKING THROUGH US THURSDAY/THURSDAY NIGHT FOR RAIN SHOWER CHANCES...BEFORE MID LEVEL HEIGHTS RISES BEGIN FRIDAY AND CONTINUE INTO THE WEEKEND FOR A RETURN TO MIDDLE 70S TO LOWER 80S TEMPS. EARLY HINTS ARE FOR NO PRECIPITATION NEXT WEEKEND WITH ALL THE HEAT AND INSTABILITY RESIDING TO OUR WEST AND SOUTH. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 106 AM EDT SUN JUN 22 2014 SUMMARY: A PLUME OF MID LEVEL MOISTURE WILL REMAIN ANCHORED ACROSS NORTHERN MICHIGAN FOR MUCH OF THE UPCOMING TAF PERIOD WITH A FEW SHOWERS FOR THE MORNING ON SUNDAY. THIS MOISTURE PLUME WILL LIFT NORTH AND EAST OF THE REGION SUNDAY NIGHT WITH SOME POTENTIAL FOR OVERNIGHT FOG DEVELOPMENT. RESTRICTIONS: ONLY THREAT FOR RESTRICTIONS THROUGH THE PERIOD WILL COME THROUGH DAYBREAK AT MBL/TVC. PRETTY MUCH A PERSISTENCE FORECAST FROM ONE DAY AGO AT MBL/TVC WITH SOME DETERIORATION LIKELY THROUGH DAYBREAK. THIS WILL LIKELY BRING A FEW PERIODS OF IFR CIGS /AND POTENTIALLY VSBYS/ TO MBL...WITH OCCASIONAL MVFR CIGS /AND POTENTIALLY VSBYS/ AT TVC. ELSEWHERE...BKN VFR CLOUDINESS AND ISOLATED SHRAS WILL CONTINUE BEFORE THINNING CLOUD COVER THIS EVENING. A FAVORABLE FOG SETUP LOOKS POSSIBLE SUNDAY NIGHT...BUT EXPECT ANY SIGNIFICANT RESTRICTIONS TO HOLD OFF UNTIL AFTER 06Z MONDAY. WINDS: LIGHT WINDS TO CONTINUE THROUGH THE EARLY MORNING HOURS BEFORE GIVING WAY TO LOCAL LAKE BREEZES IN THE AFTERNOON. WINDS WILL AGAIN DIMINISH TO CALM/LIGHT DRAINAGE WINDS THIS EVENING. LLWS: NO THREATS THIS CYCLE. && .MARINE... ISSUED AT 314 AM EDT SUN JUN 22 2014 SUMMARY: HIGH PRESSURE OVER HUDSON BAY WILL MOVE SOUTH AND EAST OFF THE ATLANTIC COAST THROUGH MONDAY ALLOWING AN AREA OF LOW PRESSURE TO MOVE INTO THE GREAT LAKES REGION FOR MONDAY NIGHT AND TUESDAY. HIGH PRESSURE BUILDS INTO THE REGION BEHIND THIS LOW FOR WEDNESDAY AND THURSDAY. HEADLINES: WINDS AND WAVES WILL REMAIN BELOW SMALL CRAFT LEVELS THROUGH MONDAY NIGHT. THERE IS SOME POTENTIAL FOR SMALL CRAFT LEVEL WINDS UNDER NORTHWEST WINDS TUESDAY/TUESDAY NIGHT AS LOW PRESSURE DEPARTS THE REGION TO THE EAST. AS LOW PRESSURE PULLS EAST OF THE REGION HIGH PRESSURE BUILDS IN FOR THE WEDNESDAY-FRIDAY TIMEFRAME WITH HEADLINE FREE CONDITIONS EXPECTED. THUNDERSTORMS: CHANCES FOR STORMS INCREASE ON MONDAY WITH A PERIOD OF THUNDERSTORMS LIKELY TUESDAY/TUESDAY NIGHT. WIDESPREAD SEVERE THREAT IS LOW...BUT ISOLATED STRONG TO SEVERE STORMS ARE POSSIBLE. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...NONE. LM...NONE. LS...NONE. && $$ UPDATE...SMITH SYNOPSIS...SMD SHORT TERM...ARNOTT LONG TERM...SMD AVIATION...ARNOTT MARINE...ARNOTT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
748 AM EDT SUN JUN 22 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 523 AM EDT SUN JUN 22 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER CNTRL SASK/MANITOBA AND A DOWNSTREAM RIDGE FROM THE NRN LAKES TO JAMES BAY. AT THE SFC...TROUGH EXTENDED INTO THE ERN DAKOTAS AND CNTRL NEBRASKA FROM LOW PRES NEAR LAKE WINNIPEG WHILE HIGH PRES PREVAILED TO THE EAST FROM SRN QUEBEC INTO THE NRN LAKES. A SHRTWV TROUGH AHEAD OF THE MID LEVEL LOW SUPPORTED SOME SHRA/TSRA FROM NW ONTARIO TO NEAR KELO. HOWEVER...THE STRONGER AND MORE WIDEPSREAD CONVECTION WAS WELL TO THE SOUTH FROM ERN NEBRASKA INTO WRN IA WHERE THE MORE FAVORABLE INSTABIILITY (MUCPAE TO NEAR 2K J/KG) AND MOISTURE TRANSPORT WAS LOCATED. OTHERWISE...MAINLY LOW STRATUS PREVAILED ACROSS MUCH OF WEST AND CENTRAL UPPER MI WHERE LOW LEVEL MOISTURE REMAINS BELOW THE 925 MB INVERSION. TODAY...EXPECT THAT THE SHRA/TSRA ASSOCIATED WITH THE MODEST FORCING ASSOCIATED WITH THE NW ONTARIO SHRTWV WILL WEAKEN AS IT MOVES TOWARD THE RIDGE. DAYTIME HEATING SHOULD BREAK UP THE LOWER CLOUDS SO THAT AFTERNOON SUNSHINE WILL PUSH TEMPS INTO THE LOWER 80S INLAND WHILE LAKE BREEZES LIMIT READINGS TO THE 60S NEAR THE GREAT LAKES. THE NAM AND SEVERAL HIGHER RES MODELS SUGGEST THAT THERE WILL BE ENOUGH INSTABILITY FOR SOME SHRA/TSRA OVER MAINLY THE WEST THIRD DURING THE AFTERNOON. HOWEVER...SINCE MORE MODEST MLCAPE VALUES INTO THE 300-600 J/KG RANGE ARE EXPECTED AND LARGE SCALE FORCING IS NOT FCST...CONFIDENCE FOR SHRA/TSRA DEVELOPMENT IS LOW AND ONLY SLIGHT CHANCE POPS WERE INCLUDED. TONIGHT...ANY CONVECTION THAT DEVELOPS DURING THE AFTERNOON WILL DIMINISH DURING THE EVENING. HOWEVER...AS THE TROUGH AND FRONTAL BOUNDARY EDGE TOWARD THE WRN CWA OVERNIGHT...SHRA/TSRA CHANCES WILL INCREASE AS ADDITIONAL WEAK SHORTWAVES EMERGE FROM THE PLAINS. THERE IS LESS CONFIDENCE IN THE EASTWARD EXTENT OF THE PCPN AS THE RIDGE TO THE EAST LIMITS THE MOVEMENT OF THE MOISTURE AXIS TO THE EAST. IN ADDITION...ANOTHER ROUND OF STRONGER CONVECTION IS MORE LIKELY OVER NRN IA OR SRN MN INTO SRN WI THAT WOULD LIMIT MOISTURE TRANSPORT TO THE NORTH. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 509 AM EDT SUN JUN 22 2014 MONDAY CONTINUES TO LOOK LIKE A SHOWERY DAY ACROSS MUCH OF THE WESTERN HALF OF UPPER MICHIGAN AS THE UPPER LOW OVER MANITOBA/SASKATCHEWAN FINALLY OPENS UP AND SLOWLY MOVES EASTWARD. MEANWHILE...A WEAK UPPER SHORT WAVE OVER THE CENTRAL PLAINS MOVES TOWARD THE REGION. THESE TWO FEATURES WILL WILL ALLOW FOR WEAK LOW PRESSURE TO DEVELOP OVER THE MID MS VLY AND MOVE TOWARD THE GREAT LAKES. MOISTURE AND WARM ADVECTION AHEAD OF THE TROUGH WILL SPREAD ACROSS THE AREA MONDAY AND BE SLOW TO MOVE OUT UNTIL THE LOW PASSES BY TUE. EXPECT SHOWERS AND ISOLATED STORMS TO DEVELOP ACROSS THE WESTERN U.P. MON MORNING THEN SLOWLY SPREAD EASTWARD DURING THE DAY AS THE 850MB TROUGH AND ASSOCIATED MOISTURE CONVERGENCE MOVES EAST. WITH THE COMBINATION OF THE FAVORABLE DYNAMICS FROM THE SHORT WAVE ENERGY AS WELL AS HIGH MOISTURE CONTENT OF THE ATMOSPHERE /PRECIPITABLE WATER VALUES AROUND 1.75 INCHES/...EXPECT A FEW AREAS ACROSS THE WEST HALF TO SEE 0.50 TO 1.0 INCHES OF RAIN MONDAY UNDER THE HEAVIEST AND MOST PERSISTENT SHOWER ACTIVITY. AS SUCH...WILL KEEP LIKELY POPS ACROSS THE ENTIRE WESTERN HALF OF THE FORECAST AREA ON MONDAY. FUTURE SHIFTS WILL LIKELY NEED TO RAISE POPS MORE...BUT THERE IS STILL SOME UNCERTAINTY EXACTLY WHERE THE BEST RAIN WILL SET UP. AS THE LOW MOVES SOUTH OF THE AREA MONDAY NIGHT...THE COLD FRONT ASSOCIATED WITH THE NORTHERN STREAM ENERGY WILL DIVE SOUTHWARD. MOISTURE WILL PERSIST ACROSS MUCH OF THE EASTERN HALF OF UPPER MICHIGAN MONDAY NIGHT COMBINED WITH SYNOPTIC FORCING FROM THE UPPER TROUGH. AS SUCH...WILL MAINTAIN LIKELY POPS EAST FOR MONDAY NIGHT TAPERING TO CHANCE POPS FOR THE WEST. TUESDAY MAY END UP BEING A FAIRLY RAW DAY ACROSS AT LEAST THE NORTHERN HALF OF UPPER MI WITH NORTHERLY FLOW BEHIND THE LOW COMBINED WITH SCATTERED SHOWERS DUE TO THE CONTINUE 850MB BAROCLINIC ZONE ACROSS THE AREA AND DEEP MOISTURE. WILL MAINTAIN CHANCE POPS ACROSS THE ENTIRE AREA ALTHOUGH CLOSER TO LAKE SUPERIOR MAY SEE MORE DRIZZLE THAN ANYTHING. AREAS CLOSE TO LAKE SUPERIOR MAY STRUGGLE TO RISE OUT OF THE MID 50S ON TUESDAY ALTHOUGH INLAND AREAS WILL SEE TEMPS RISE WELL INTO THE 60S. FOR TUE NIGHT/WED...HIGH PRESSURE BUILDS ACROSS THE AREA LEADING TO A DRY PERIOD THROUGH WED NIGHT. HIGH PRESSURE HANGS ON THRU THU ALTHOUGH THE ECMWF AND GFS BOTH SUGGEST ANOTHER SHORT WAVE MOVING INTO THE UPPER LAKES DURING THE DAY WHICH MAY ALLOW FOR SHOWERS AND ISOLATED STORMS DURING THE AFTERNOON. UPPER RIDGING FINALLY BUILDS IN FOR THE WEEKEND WHICH MEANS TEMPERATURES RISING TO ABOVE NORMAL. MAY BE A CHANCE FOR RAIN FRI NIGHT INTO SATURDAY AS WEAK WARM ADVECTION DEVELOPS...BUT LATEST ECMWF SUGGESTS THAT THE RAIN CHANCES WILL HOLD OFF UNTIL SAT NIGHT/SUN. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 748 AM EDT SUN JUN 22 2014 THE COMBINATION OF DAYTIME HEATING AND SOME LOW LEVEL DRYING WILL ALLOW THE FOG/STRATUS TO BURN OFF AND CONDITIONS TO TRANSITION GRADUALLY TO VFR BY NOON. MORE FOG AND LOW CLOUDS COULD ROLL IN OFF LAKE SUPERIOR THIS EVENING AT CMX. A FEW SHOWERS ARE POSSIBLE OVERNIGHT AT CMX AND IWD BUT ARE NOT EXPECTED TO REDUCE CONDITIONS BELOW VFR. A THUNDERSTORMS IS ALSO POSSIBLE BUT CONFIDENCE IS TOO LOW TO INCLUDE MENTION IN THE TAF. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 523 AM EDT SUN JUN 22 2014 DENSE FOG WILL CONTINUE TO BE THE MAIN CONCERN ACROSS WEST AND CENTRAL LAKE SUPERIOR. LINGERING LOW LEVEL MOISTURE WITH PERSISTENT LIGHT E OR SE LOW LEVEL FLOW WILL ALLOW FOR DENSE FOG WILL HELP TO MAINTAIN THE FOG OR LOW STRATUS TODAY. THERE MAY BE ENOUGH DRY AIR MOVING IN THIS AFTERNOON TO MIX OUT THE FOG BUT THERE IS THE POSSIBILITY THAT AN EXTENSION OF THE DENSE FOG ADVISORY MAY BE NEEDED. WINDS WILL REMAIN AT OR BELOW 20 KNOTS THROUGH THIS FORECAST PERIOD. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... DENSE FOG ADVISORY UNTIL 11 AM EDT /10 AM CDT/ THIS MORNING FOR LSZ162-240>248-263>265. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...MRD AVIATION...JLB MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
525 AM EDT SUN JUN 22 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 523 AM EDT SUN JUN 22 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER CNTRL SASK/MANITOBA AND A DOWNSTREAM RIDGE FROM THE NRN LAKES TO JAMES BAY. AT THE SFC...TROUGH EXTENDED INTO THE ERN DAKOTAS AND CNTRL NEBRASKA FROM LOW PRES NEAR LAKE WINNIPEG WHILE HIGH PRES PREVAILED TO THE EAST FROM SRN QUEBEC INTO THE NRN LAKES. A SHRTWV TROUGH AHEAD OF THE MID LEVEL LOW SUPPORTED SOME SHRA/TSRA FROM NW ONTARIO TO NEAR KELO. HOWEVER...THE STRONGER AND MORE WIDEPSREAD CONVECTION WAS WELL TO THE SOUTH FROM ERN NEBRASKA INTO WRN IA WHERE THE MORE FAVORABLE INSTABIILITY (MUCPAE TO NEAR 2K J/KG) AND MOISTURE TRANSPORT WAS LOCATED. OTHERWISE...MAINLY LOW STRATUS PREVAILED ACROSS MUCH OF WEST AND CENTRAL UPPER MI WHERE LOW LEVEL MOISTURE REMAINS BELOW THE 925 MB INVERSION. TODAY...EXPECT THAT THE SHRA/TSRA ASSOCIATED WITH THE MODEST FORCING ASSOCIATED WITH THE NW ONTARIO SHRTWV WILL WEAKEN AS IT MOVES TOWARD THE RIDGE. DAYTIME HEATING SHOULD BREAK UP THE LOWER CLOUDS SO THAT AFTERNOON SUNSHINE WILL PUSH TEMPS INTO THE LOWER 80S INLAND WHILE LAKE BREEZES LIMIT READINGS TO THE 60S NEAR THE GREAT LAKES. THE NAM AND SEVERAL HIGHER RES MODELS SUGGEST THAT THERE WILL BE ENOUGH INSTABILITY FOR SOME SHRA/TSRA OVER MAINLY THE WEST THIRD DURING THE AFTERNOON. HOWEVER...SINCE MORE MODEST MLCAPE VALUES INTO THE 300-600 J/KG RANGE ARE EXPECTED AND LARGE SCALE FORCING IS NOT FCST...CONFIDENCE FOR SHRA/TSRA DEVELOPMENT IS LOW AND ONLY SLIGHT CHANCE POPS WERE INCLUDED. TONIGHT...ANY CONVECTION THAT DEVELOPS DURING THE AFTERNOON WILL DIMINISH DURING THE EVENING. HOWEVER...AS THE TROUGH AND FRONTAL BOUNDARY EDGE TOWARD THE WRN CWA OVERNIGHT...SHRA/TSRA CHANCES WILL INCREASE AS ADDITIONAL WEAK SHORTWAVES EMERGE FROM THE PLAINS. THERE IS LESS CONFIDENCE IN THE EASTWARD EXTENT OF THE PCPN AS THE RIDGE TO THE EAST LIMITS THE MOVEMENT OF THE MOISTURE AXIS TO THE EAST. IN ADDITION...ANOTHER ROUND OF STRONGER CONVECTION IS MORE LIKELY OVER NRN IA OR SRN MN INTO SRN WI THAT WOULD LIMIT MOISTURE TRANSPORT TO THE NORTH. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 509 AM EDT SUN JUN 22 2014 MONDAY CONTINUES TO LOOK LIKE A SHOWERY DAY ACROSS MUCH OF THE WESTERN HALF OF UPPER MICHIGAN AS THE UPPER LOW OVER MANITOBA/SASKATCHEWAN FINALLY OPENS UP AND SLOWLY MOVES EASTWARD. MEANWHILE...A WEAK UPPER SHORT WAVE OVER THE CENTRAL PLAINS MOVES TOWARD THE REGION. THESE TWO FEATURES WILL WILL ALLOW FOR WEAK LOW PRESSURE TO DEVELOP OVER THE MID MS VLY AND MOVE TOWARD THE GREAT LAKES. MOISTURE AND WARM ADVECTION AHEAD OF THE TROUGH WILL SPREAD ACROSS THE AREA MONDAY AND BE SLOW TO MOVE OUT UNTIL THE LOW PASSES BY TUE. EXPECT SHOWERS AND ISOLATED STORMS TO DEVELOP ACROSS THE WESTERN U.P. MON MORNING THEN SLOWLY SPREAD EASTWARD DURING THE DAY AS THE 850MB TROUGH AND ASSOCIATED MOISTURE CONVERGENCE MOVES EAST. WITH THE COMBINATION OF THE FAVORABLE DYNAMICS FROM THE SHORT WAVE ENERGY AS WELL AS HIGH MOISTURE CONTENT OF THE ATMOSPHERE /PRECIPITABLE WATER VALUES AROUND 1.75 INCHES/...EXPECT A FEW AREAS ACROSS THE WEST HALF TO SEE 0.50 TO 1.0 INCHES OF RAIN MONDAY UNDER THE HEAVIEST AND MOST PERSISTENT SHOWER ACTIVITY. AS SUCH...WILL KEEP LIKELY POPS ACROSS THE ENTIRE WESTERN HALF OF THE FORECAST AREA ON MONDAY. FUTURE SHIFTS WILL LIKELY NEED TO RAISE POPS MORE...BUT THERE IS STILL SOME UNCERTAINTY EXACTLY WHERE THE BEST RAIN WILL SET UP. AS THE LOW MOVES SOUTH OF THE AREA MONDAY NIGHT...THE COLD FRONT ASSOCIATED WITH THE NORTHERN STREAM ENERGY WILL DIVE SOUTHWARD. MOISTURE WILL PERSIST ACROSS MUCH OF THE EASTERN HALF OF UPPER MICHIGAN MONDAY NIGHT COMBINED WITH SYNOPTIC FORCING FROM THE UPPER TROUGH. AS SUCH...WILL MAINTAIN LIKELY POPS EAST FOR MONDAY NIGHT TAPERING TO CHANCE POPS FOR THE WEST. TUESDAY MAY END UP BEING A FAIRLY RAW DAY ACROSS AT LEAST THE NORTHERN HALF OF UPPER MI WITH NORTHERLY FLOW BEHIND THE LOW COMBINED WITH SCATTERED SHOWERS DUE TO THE CONTINUE 850MB BAROCLINIC ZONE ACROSS THE AREA AND DEEP MOISTURE. WILL MAINTAIN CHANCE POPS ACROSS THE ENTIRE AREA ALTHOUGH CLOSER TO LAKE SUPERIOR MAY SEE MORE DRIZZLE THAN ANYTHING. AREAS CLOSE TO LAKE SUPERIOR MAY STRUGGLE TO RISE OUT OF THE MID 50S ON TUESDAY ALTHOUGH INLAND AREAS WILL SEE TEMPS RISE WELL INTO THE 60S. FOR TUE NIGHT/WED...HIGH PRESSURE BUILDS ACROSS THE AREA LEADING TO A DRY PERIOD THROUGH WED NIGHT. HIGH PRESSURE HANGS ON THRU THU ALTHOUGH THE ECMWF AND GFS BOTH SUGGEST ANOTHER SHORT WAVE MOVING INTO THE UPPER LAKES DURING THE DAY WHICH MAY ALLOW FOR SHOWERS AND ISOLATED STORMS DURING THE AFTERNOON. UPPER RIDGING FINALLY BUILDS IN FOR THE WEEKEND WHICH MEANS TEMPERATURES RISING TO ABOVE NORMAL. MAY BE A CHANCE FOR RAIN FRI NIGHT INTO SATURDAY AS WEAK WARM ADVECTION DEVELOPS...BUT LATEST ECMWF SUGGESTS THAT THE RAIN CHANCES WILL HOLD OFF UNTIL SAT NIGHT/SUN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 127 AM EDT SUN JUN 22 2014 WITH LINGERING LLVL MSTR UNDER MID LVL SUBSIDENCE/DRYING...EXPECT WIDESPREAD STATUS AND FOG IN THE PRESENCE OF NOCTURNAL COOLING TNGT. IFR/LIFR CONDITIONS WL BE THE RULE...WITH EVEN VLIFR/BLO LANDING MINIMUM CONDITIONS AT CMX WITH AN E UPSLOPE WIND. NOT OUT OF THE QUESTION THERE COULD BE BLO LANDING MIN CONDITIONS AT SAW AND IWD TOO. THE COMBINATION OF DAYTIME HEATING AND SOME LLVL DRYING WL ALLOW THE FOG/STRATUS TO BURN OFF AND CONDITIONS TO TRANSITION GRADUALLY TO VFR BY NOON. MORE FOG AND LO CLDS COULD ROLL IN OFF LK SUP THIS EVNG AT CMX. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 523 AM EDT SUN JUN 22 2014 DENSE FOG WILL CONTINUE TO BE THE MAIN CONCERN ACROSS WEST AND CENTRAL LAKE SUPERIOR. LINGERING LOW LEVEL MOISTURE WITH PERSISTENT LIGHT E OR SE LOW LEVEL FLOW WILL ALLOW FOR DENSE FOG WILL HELP TO MAINTAIN THE FOG OR LOW STRATUS TODAY. THERE MAY BE ENOUGH DRY AIR MOVING IN THIS AFTERNOON TO MIX OUT THE FOG BUT THERE IS THE POSSIBILITY THAT AN EXTENSION OF THE DENSE FOG ADVISORY MAY BE NEEDED. WINDS WILL REMAIN AT OR BELOW 20 KNOTS THROUGH THIS FORECAST PERIOD. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... DENSE FOG ADVISORY UNTIL 11 AM EDT /10 AM CDT/ THIS MORNING FOR LSZ162-240>248-263>265. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...MRD AVIATION...KC MARINE...JLB
AREA FORECAST DISCUSSION
NWS GAYLORD MI
316 AM EDT SUN JUN 22 2014 .SYNOPSIS... ISSUED AT 314 AM EDT SUN JUN 22 2014 NORTHERN MICHIGAN WILL REMAIN BETWEEN HIGH PRESSURE SINKING INTO THE EASTERN GREAT LAKES TODAY...AND LOW PRESSURE OVER THE UPPER MISSISSIPPI VALLEY. THERE WILL BE A FEW SHOWERS THIS MORNING...BUT A BETTER SHOT OF SHOWERS AND THUNDERSTORMS...WILL ARRIVE LATER MONDAY AND MONDAY NIGHT. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 314 AM EDT SUN JUN 22 2014 ...SOME SPOTTY SHOWERS THIS MORNING... HIGH IMPACT WEATHER POTENTIAL: PATCHY FOG DEVELOPING AFTER MIDNIGHT SUNDAY NIGHT/MONDAY MORNING. PATTERN SUMMARY/IMPLICATIONS: VERY SIMILAR STORY TO WHAT WE DISCUSSED 24 HOURS AGO WITH CLOSED LOW SITTING OVER MANITOBA/SASKATCHEWAN WITH DOWNSTREAM RIDGING OVER MICHIGAN NORTH INTO ONTARIO SQUEEZED AGAINST LARGER SCALE TROUGHING OVER EASTERN CANADA. SHORTWAVES CONTINUE TO SHEAR OUT AS THEY RUN INTO THE OVERHEAD RIDGE AXIS...WITH THE MOST RECENT WAVE OF DEEP MOISTURE NOW BEGINNING TO PULL EAST OF THE STATE. DRILLING DOWN TO THE SURFACE ALSO REVEALS STRONG SIMILARITY TO ONE DAY AGO WITH HIGH PRESSURE ANCHORED OVER HUDSON BAY AND A SURFACE LOW BENEATH THE CLOSE FEATURE OVER MANITOBA. BETWEEN THESE FEATURES...A PLUME OF DEEPER MOISTURE REMAINS STALLED OVER NORTHERN MICHIGAN. WEAK POSITIVE THETAE ADVECTION AT H8 CONTINUES TO FORCE SHRAS PRIMARILY OVER THE NORTHEASTERN HALF OF THE CWA. GIVEN THE STAGNANT NATURE OF THE PATTERN...FORECAST CHALLENGES WILL CONTINUE TO REVOLVE AROUND LIGHT PRECIPITATION POTENTIAL WITH ASSOCIATED CLOUDS/IMPACTS ON TEMPERATURES. TODAY... PRECIPITATION CHANCES: OVERHEAD H8 THETAE GRADIENT STALLS OVER EASTERN CHIP/MACK SOUTH AND EAST ACROSS NORTHEAST LOWER THROUGH NOON BEFORE BEING PUSHED NORTH AND EAST. WITH DEEP MOISTURE WANING /SEE CURRENT WV IMAGERY/...EXPECT COVERAGE IN SHOWER ACTIVITY ASSOCIATED WITH THIS GRADIENT TO WEAKEN...BUT LIKELY NOT QUIT THROUGH THE MORNING HOURS...WARRANTING A CHANCE POP/SCATTERED WORDING HERE. AS WE LOOK INTO THE AFTERNOON...FOCUS TURNS TO POPPING ANY DIURNAL CONVECTION WITH A SOMEWHAT MOISTER LLEVEL AIRMASS THAN 24 HOURS PREVIOUS. STILL THINK THE NAM IS TOO ROBUST WITH LLEVEL MOISTURE...BUT EVEN THE FAR MORE CONSERVATIVE RAP ALLOWS FOR 500-750 JOULES OF MUCAPE DEVELOPMENT OVER THE HIGH TERRAIN OF INTERIOR NORTHERN LOWER. QG FORCING FOR ASCENT IS NIL OVERHEAD WITH SLOWLY BUILDING HEIGHTS ALOFT REQUIRING LAKE BREEZES/UPSLOPE CONVERGENCE TO PUSH US TO CONVECTIVE INITIATION. HAVE TROUBLE BELIEVING WE CAN GET AROUND MODEST CAPPING NEAR H7 PURELY WITH BOUNDARY LAYER PROCESSES. THUS...WILL MAINTAIN GOING DRY FORECAST FOR THE AFTERNOON HOURS. QPF: BASIN WIDE AMOUNTS VERY LIGHT...LESS THAN 0.05". ISOLATED LOCATIONS COULD RECEIVE NEAR 0.20" GIVEN MODEST PWATS/WARM CLOUD DEPTHS AND LIGHT STEERING FLOW. TEMPERATURES: T8S NEAR +12C AT 00Z WITH CONTINUED SLOW WARMING THROUGH TODAY SUGGESTS WE SHOULD BE ABLE TO BEST YESTERDAYS HIGHS AND GUIDANCE CONSENSUS HANDLES THIS WELL...WITH MID/UPPER 70S INLAND AND CLOSER TO 70 AT THE LAKE-BREEZE COOLED COASTS. WINDS: CONTINUED LIGHT GRADIENT FAVORS ROBUST LAKE BREEZE DEVELOPMENT THIS AFTERNOON. TONIGHT... PRECIPITATION CHANCES: WITH NO HELPFUL LLEVEL MOISTURE ADVECTION...CHANCES WILL BE CONTINGENT ON AFTERNOON ACTIVITY PERSISTING INTO THE EVENING. GIVEN THE CURRENT EXPECTATION THAT WE/LL REMAIN SHOWER FREE THROUGH THE AFTERNOON...WILL MAINTAIN DRY CONDITIONS THROUGH THE TONIGHT PERIOD AS WELL. QPF: NIL. TEMPERATURES: WILL STICK NEAR GUIDANCE CONSENSUS IN THE MID 50S AS PARTLY CLOUDY SKIES SHOULD ALLOW FOR MODEST RADIATIONAL COOLING WITH GEOSTROPHIC FLOW AT 1000MB NEAR 10KTS LIKELY STILL ALLOW MOST LOCATIONS TO DECOUPLE. WINDS: CALM OR LIGHT DRAINAGE FLOWS EXPECTED. FOG: WITH MID/UPPER LEVEL MOISTURE BEGINNING TO PULL EAST...CAN SEE SOME INCREASED FOG POTENTIAL AS LLEVEL FLOW GAINS A SOUTHWESTERLY COMPONENT WITH CONTINUED WEAK LLEVEL MOISTURE ADVECTION AND ENOUGH CLEARING FOR RADIATIONAL COOLING IN THE PRESENCE OF ELEVATED 2M DEWPOINTS. WILL ADD PATCHY FOG TO THE FORECAST AFTER MIDNIGHT. && .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 314 AM EDT SUN JUN 22 2014 ...SCATTERED THUNDERSTORMS MONDAY AND MONDAY NIGHT... IMPACTS: MINIMAL. SEVERE STORMS STILL LOOK UNLIKELY. SYNOPTIC PATTERN/EVOLUTION: THE ENTIRE FORECAST PERIOD OF MONDAY THROUGH THE NEXT WEEKEND WILL SEE A SHALLOW AND PROGRESSIVE MID LEVEL AMPLITUDE PATTERN THROUGH A GOOD CHUNK OF THE WORK WEEK. THEN...HEIGHTS RISE OVER THE HEART OF THE COUNTRY...INCLUDING THE WESTERN GREAT LAKES. THIS IS IN RESPONSE TO TWO LARGE UPPER/CLOSED LOWS DROPPING INTO THE PAC NW/NEW ENGLAND. AN INCREASINGLY MUGGIER AIR MASS MONDAY AND EARLY TUESDAY...AHEAD OF AN APPROACHING AREA OF LOW PRESSURE AND PRECIPITATION...WILL GET COOLED AND DRIED DOWN LATER TUESDAY THROUGH WEDNESDAY. TEMPERATURES WILL START RISING BACK UP AGAIN FOR LATE IN THE WORK WEEK. PRECIPITATION CHANCES AFTER EARLY TUESDAY DO NOT LOOK ALL THAT FANTASTIC. MON-TUES: THE BEST ACTION RESIDES IN THIS TIME FRAME. SHALLOW RIDGING EXITS EAST...WHILE AN ELONGATED UPPER TROUGH AXIS ACROSS ONTARIO BACKS WINDS ALOFT WSW. SHORTWAVE ENERGY AND AN ASSOCIATED SFC LOW WILL LIFT UP ACROSS NRN MICHIGAN. THIS LOW PRESSURE DOESN`T LOOK ALL THAT IMPRESSIVE...BUT A WARM FRONT WILL EDGE UP THROUGH MUCH OF NRN LOWER...WITH THE TRAILING COLD FRONT EXITING NEAR TUESDAY MORNING. AS THE SFC LOW DEPARTS...ANOTHER COLD FRONT...ONE WITH MORE REFRESHING AIR...WILL SLIDE SOUTHWARD THROUGH NRN MICHIGAN BY OVER NIGHT TUESDAY NIGHT (UNCERTAINTY ON EXACT TIMING). COULD SEE SOME SHOWERS POSSIBLY SNEAKING INTO A FEW SECTIONS OF NW LOWER MONDAY MORNING...AND ALSO SOME POTENTIAL CONVECTIVE DEBRIS FROM FURTHER WEST...BUT THE USING AN EXPECTED AVERAGE PARCEL OF 80/61 (DEW POINT IS SOME QUESTION)...CAN POSSIBLY GLEAN 1000-1300 J/KG MONDAY LATE AFTERNOON. RIGHT WITH THE WARM FRONTAL ARRIVAL. THE LOW TRACKS OVER NRN MICHIGAN WITH MAINLY NRN LOWER SNEAKING INTO THE WARM SECTOR FOR THE EVENING (TIMING ALSO IN SOME QUESTION). SHOWER AND STORM CHANCES WILL BE GREATEST MONDAY NIGHT...AND ALTHOUGH NOTHING OVERLY IMPRESSIVE...WILL HAVE TO WATCH THE DEVELOPMENTS SURROUNDING WIND FIELDS AND INSTABILITY. THERE IS A TIGHTENING IN THE MID LEVEL FLOW (40KTS)...AND IF THE INSTABILITY ABOVE CAN BE HAD...AND BEING IN THE WARM SECTOR...WHILE EASTERN UPPER GETS GARDEN VARIETY SHOWERS AND A FEW STORMS...NRN LOWER COULD SEE STRONGER CELLS. CELLS THAT WILL BE IN A BETTER ENVIRONMENT FOR GUSTY WINDS/SMALLISH HAIL AND THE POSSIBILITY OF A ROGUE TORNADO. THAT`S AN AWFUL LOT OF IF`S THOUGH. AFTER THE LOW DEPARTS...AND SECONDARY COOL FRONT GETS DROPPED THROUGH US...WITH MINIMAL FORCING...DIMINISHING MOISTURE AND A TOTAL LACK OF INSTABILITY DUE TO MORE OF A COL AREA IN STORE FOR US. HIGHS WELL INTO THE 70S MONDAY WILL START COOLING OFF...WITH HIGHS TUESDAY IN THE UPPER 60S/70F IN EASTERN UPPER...AND UPPER 70S NEARER SAGINAW BAY. WEDNESDAY THROUGH NEXT WEEKEND: AN EVEN COOLER DAY WEDNESDAY WITH HIGHS IN THE MAINLY IN THE 60S...A FEW LOWER 70S...AS HIGH PRESSURE SLIPS INTO OUR NECK OF THE WOODS FROM ONTARIO. SHOULD BE A BEAUTIFUL DAY. THERE ARE DEFINITE HINTS AT SOME SHORTWAVE ACTIVITY TRACKING THROUGH US THURSDAY/THURSDAY NIGHT FOR RAIN SHOWER CHANCES...BEFORE MID LEVEL HEIGHTS RISES BEGIN FRIDAY AND CONTINUE INTO THE WEEKEND FOR A RETURN TO MIDDLE 70S TO LOWER 80S TEMPS. EARLY HINTS ARE FOR NO PRECIPITATION NEXT WEEKEND WITH ALL THE HEAT AND INSTABILITY RESIDING TO OUR WEST AND SOUTH. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 106 AM EDT SUN JUN 22 2014 SUMMARY: A PLUME OF MID LEVEL MOISTURE WILL REMAIN ANCHORED ACROSS NORTHERN MICHIGAN FOR MUCH OF THE UPCOMING TAF PERIOD WITH A FEW SHOWERS FOR THE MORNING ON SUNDAY. THIS MOISTURE PLUME WILL LIFT NORTH AND EAST OF THE REGION SUNDAY NIGHT WITH SOME POTENTIAL FOR OVERNIGHT FOG DEVELOPMENT. RESTRICTIONS: ONLY THREAT FOR RESTRICTIONS THROUGH THE PERIOD WILL COME THROUGH DAYBREAK AT MBL/TVC. PRETTY MUCH A PERSISTENCE FORECAST FROM ONE DAY AGO AT MBL/TVC WITH SOME DETERIORATION LIKELY THROUGH DAYBREAK. THIS WILL LIKELY BRING A FEW PERIODS OF IFR CIGS /AND POTENTIALLY VSBYS/ TO MBL...WITH OCCASIONAL MVFR CIGS /AND POTENTIALLY VSBYS/ AT TVC. ELSEWHERE...BKN VFR CLOUDINESS AND ISOLATED SHRAS WILL CONTINUE BEFORE THINNING CLOUD COVER THIS EVENING. A FAVORABLE FOG SETUP LOOKS POSSIBLE SUNDAY NIGHT...BUT EXPECT ANY SIGNIFICANT RESTRICTIONS TO HOLD OFF UNTIL AFTER 06Z MONDAY. WINDS: LIGHT WINDS TO CONTINUE THROUGH THE EARLY MORNING HOURS BEFORE GIVING WAY TO LOCAL LAKE BREEZES IN THE AFTERNOON. WINDS WILL AGAIN DIMINISH TO CALM/LIGHT DRAINAGE WINDS THIS EVENING. LLWS: NO THREATS THIS CYCLE. && .MARINE... ISSUED AT 314 AM EDT SUN JUN 22 2014 SUMMARY: HIGH PRESSURE OVER HUDSON BAY WILL MOVE SOUTH AND EAST OFF THE ATLANTIC COAST THROUGH MONDAY ALLOWING AN AREA OF LOW PRESSURE TO MOVE INTO THE GREAT LAKES REGION FOR MONDAY NIGHT AND TUESDAY. HIGH PRESSURE BUILDS INTO THE REGION BEHIND THIS LOW FOR WEDNESDAY AND THURSDAY. HEADLINES: WINDS AND WAVES WILL REMAIN BELOW SMALL CRAFT LEVELS THROUGH MONDAY NIGHT. THERE IS SOME POTENTIAL FOR SMALL CRAFT LEVEL WINDS UNDER NORTHWEST WINDS TUESDAY/TUESDAY NIGHT AS LOW PRESSURE DEPARTS THE REGION TO THE EAST. AS LOW PRESSURE PULLS EAST OF THE REGION HIGH PRESSURE BUILDS IN FOR THE WEDNESDAY-FRIDAY TIMEFRAME WITH HEADLINE FREE CONDITIONS EXPECTED. THUNDERSTORMS: CHANCES FOR STORMS INCREASE ON MONDAY WITH A PERIOD OF THUNDERSTORMS LIKELY TUESDAY/TUESDAY NIGHT. WIDESPREAD SEVERE THREAT IS LOW...BUT ISOLATED STRONG TO SEVERE STORMS ARE POSSIBLE. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...NONE. LM...NONE. LS...NONE. && $$ SYNOPSIS...SMD SHORT TERM...ARNOTT LONG TERM...SMD AVIATION...ARNOTT MARINE...ARNOTT
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
858 PM CDT MON JUN 23 2014 .UPDATE...AFTERNOON CONVECTION MOVING OFF INTO ALABAMA THIS EVENING BUT ANOTHER ROUND OF STORMS IS MOVING INTO THE DELTA. THIS COMPLEX OF STORMS IS LOCATED BETWIXT TWO UPPER LEVEL JET STRUCTURES...ONE OVER TEXAS AND ANOTHER RIDING UP INTO MISSOURI. THIS IS HELPING TO FEED THIS COMPLEX MORE THAN JUST DAYTIME HEATING. IN ADDITION...THERE IS PLENTY OF LOW LEVEL FLOW FEEDING GOOD MOISTURE INTO THIS REGION. LATEST RUNS OF THE HRRR AND LOCAL WRF INDICATE THAT THIS SYSTEM WILL MAINTAIN SOME STRENGTH AND PUSH EAST ACROSS AT LEAST THE NORTHERN PORTIONS OF THE CWA. THIS...HOWEVER...IS NOT DEPICTED IN OTHER HI-RES MODEL RUNS. WITH THIS IN MIND...HAVE KEPT NUMEROUS COVERAGE IN THE NORTHERN PORTIONS OF THE CWA FOR TONIGHT. THERE ALSO IS POTENTIAL FOR SOME HEAVY RAIN WITH THESE STORMS ALONG WITH FREQUENT LIGHTNING. GOING FORECAST APPEARS TO BE IN DECENT SHAPE WITH ONLY MINOR ADJUSTMENTS MADE FOR HOURLY CONDITIONS. /28/ && .AVIATION...THUNDERSTORM COMPLEX OVER AR/NRN LA BEING SUPPORTED BY FAVORABLE JET STREAM DYNAMICS AND GOOD LOW LEVEL MOISTURE TRANSPORT. LATEST HRRR AND LOCAL WRF GUIDANCE SUGGEST STORMS FROM THIS COMPLEX COULD INCREASE ACROSS THE GLH/GWO/JAN/HKS AREA OVERNIGHT AND PERSIST UNTIL WELL AFTER MIDNIGHT. OTHERWISE...PLENTY OF MID/HIGH LEVEL CLOUDINESS MOVING ACROSS THE AREA AND GREATER LOW LEVEL MIXING SHOULD LIMIT FOG PRODUCTION...BUT THERE COULD BE A BIT MORE MVFR CATEGORY STRATOCU DURING THE 09-15Z TIME FRAME GIVEN INCREASING MOIST SOUTHWESTERLY LL FLOW. EXPECT STRATOCU DECK TO MIX OUT WITH ABUNDANT CUMULUS DEVELOPING IN THE AFTERNOON AND PERHAPS A FEW SHRA/TSRA. /EC/ && .PREV DISCUSSION... /ISSUED 344 PM CDT MON JUN 23 2014/ SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT...CONVECTION UNFOLDING ACROSS THE REGION ABOUT AS EXPECTED THIS AFTERNOON WITH MAJORITY IN THE EAST. SHORTWAVE RIDGING INDICATED WELL ON SATELLITE IMAGERY WITH MARKED DECREASE IN OVERALL CLOUD PRODUCTION OVER E AR/NE LA. MCV...FROM OVERNIGHT CONVECTION... SPINNING ABOUT OVER NE OK AT THE MOMENT WITH OUTFLOW BOUNDARY/WEAK SURFACE FRONT ANCHORED TO IT. BOTH OF THESE FEATURES ARE SERVING TO ENHANCE CONVECTIVE DEVELOPMENT OVER THE ARKLATEX REGION AND WILL HAVE AN INFLUENCE ON OUR WEATHER OVERNIGHT. CO-LOCATED WITH THE MCV AND OUTFLOW BOUNDARY AT A LARGER SCALE IS A RATHER DECENT MID/UPPER LEVEL SHORTWAVE STRETCHING NORTHWARD INTO THE MID MS VALLEY. WITH SUPPORT ALOFT...BELIEVE LOW LEVEL FEATURES WILL BE SUSTAINED WITH THE TROF AS THEY MOVE EAST OVERNIGHT. MODELS ARE ALSO HANDLING THE ENHANCED 25-35 KNOT H85 FLOW ANALYZED OVER E TX THIS MORNING IN BRINGING IT NE IN ADVANCE OF THE LOW LEVEL FEATURES TONIGHT. THIS WILL PROVIDE ISENTROPIC LIFT...AS WELL AS...GOOD THETA-E ADVECTION IN ORDER TO MAINTAIN CONVECTIVE POTENTIAL OVERNIGHT. WHILE WOULD NOT BE SURPRISED TO SEE SOME STRONG STORMS OVER N MS OVERNIGHT GIVEN 0-1 KM BULK SHEAR AROUND 25 KNOTS...MEAGER LAPSE RATES SHOULD KEEP MORE INTENSE STORMS AT BAY. AM MORE CONCERNED ABOUT THE HEAVY RAINFALL POTENTIAL GIVEN PW/S NEAR 2 INCHES...STEADY INFLUX OF HIGH THETA-E AIR AND SLOWING SURFACE BOUNDARY. WHILE CONFIDENCE IS HIGH THAT HEAVY RAINFALL WILL BE A CONCERN IN STORMS OVER NORTH MS TONIGHT...CONFIDENCE IS LOW ON WHAT EXACT SCENARIO WILL OCCUR WITH HIGH VARIANCE IN HIRES MODEL OUTPUT. SOME UNCERTAINTY EXISTS AS WELL TOMORROW IN CONVECTIVE SCENARIO AS THESE FEATURES LOOK TO POSSIBLY PULL EAST DURING THE LATE MORNING. REGARDLESS...SCATTERED CONVECTION STILL LOOKS LIKE A GOOD BET AS SOUPY AIRMASS REMAINS. TUESDAY NIGHT INTO THURSDAY IS LOOKING MORE LIKE THE CLIMATOLOGICAL NORM FOR POPS AS RIDGING ALOFT AND PW/S AROUND OR BELOW 1.5 INCHES SHOULD ALLOW A MORE ISOLATED COVERAGE OF CONVECTION TO CONTEND WITH. DECIDED TO UP MINS AND LOWER MAXES A COUPLE DEGREES DURING THIS PERIOD GIVEN TRENDS LAST COUPLE OF DAYS DURING THIS WET PERIOD./26/ LONG TERM...THURSDAY THROUGH MONDAY...AN UNSEASONABLY WET PATTERN WILL SPILL OVER INTO THE LONG TERM PORTION OF THE FORECAST AS SUBTLE UPPER TROUGHING SETS UP OVER THE CENTRAL CONUS. IN SPITE OF THIS FEATURE...CONVECTION WILL LIKELY REMAIN MOSTLY DIURNAL IN NATURE AS IT WILL LARGELY BE DRIVEN BY INSTABILITY WITH A LACK OF SIGNIFICANT MID/UPPER LEVEL FLOW FOR STORM ORGANIZATION. NEVERTHELESS...SCATTERED TO NUMEROUS COVERAGE OF SHOWERS AND STORMS IS EXPECTED FOR THURSDAY. FOR THE END OF THE WEEK...THE EURO CONTINUES TO SHOW MID/UPPER RIDGING BEGINNING TO BUILD NORTHWARD FROM THE NORTHERN GULF. THIS IS SUPPORTED BY THE ECM ENSEMBLE WHICH ALSO INDICATES MEAN RIDGING DEVELOPING OVER THE NORTHERN GULF/SOUTHEAST US. THIS WILL BEGIN TO PUSH DAILY CONVECTION OUTSIDE OF THE AREA AS MID LEVEL TEMPS WARM AND SUPPRESSION INCREASES. IT WILL ALSO ALLOW DAYTIME HIGHS TO INCREASE BY A FEW DEGREES WITH FEWER CLOUDS/OUTFLOW BOUNDARIES AROUND. THIS REGIME WILL CONTINUE INTO EARLY NEXT WEEK...THUS POPS WERE TRENDED DOWNWARD THROUGH THIS PERIOD. /DL/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 69 89 70 91 / 46 44 29 18 MERIDIAN 68 90 68 92 / 43 42 45 17 VICKSBURG 72 89 70 90 / 54 42 20 19 HATTIESBURG 72 92 71 91 / 40 28 20 22 NATCHEZ 72 89 70 89 / 27 24 18 25 GREENVILLE 73 88 70 92 / 68 28 18 18 GREENWOOD 70 86 69 92 / 64 43 20 18 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ 28/EC/26/DL
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
102 PM CDT Sun Jun 22 2014 .SHORT TERM: (Through Late This Afternoon) Issued at 336 AM CDT Sun Jun 22 2014 Once again the main forecast issue is thunderstorm chances. The only ongoing precipitation early this morning is a shrinking area of showers in Pike Co MO. This originated from a NW-SE cluster of thunderstorms which occurred just north of Mexico in response to lift via a weak westerly LLJ along the cool side of a large scale outflow boundary. That boundary remains somewhat identifiable from far southern IL into central/NW MO. While there is no clear cut model solution, there are suggestions by the deterministic guidance which are supported by recent runs of the HRRR and the 4km NSSL WRF that this confluent zone from central through southeast MO will be the region of scattered thunderstorm development beginning near midday, with activity shifting east thru the afternoon. There may be a region of somewhat greater coverage and organization across northeast Missouri and west central IL resulting from an eastward migrating vort max which is now present in the central Plains. Highs once again look seasonable in the upper 80s to lower 90s. Glass .LONG TERM: (Tonight through Saturday) Issued at 336 AM CDT Sun Jun 22 2014 The greatest threat of thunderstorms tonight should also reside across the northern portion of the CWA where the consensus of the model QPFs have the highest coverage. This appears reasonable as a cold front will be pushing into IA and NW MO in association with a much better defined slowly progressive short wave trof and attendant vort maxes. Strengthening and veering wind fields and a stronger veering WSW LLJ should result in good eastward progression of organized convection. The cold front will move slowly across the area Monday and Monday night and should be accompanied by fairly widespread showers and thunderstorms. The models vary on how far south the front will push on Tuesday with the NAM showing the least progression only into southern IL and southern MO while the GFS and SREF push the front into AR. Eventually the front will retreat back northward and be the focus for additional showers and thunderstorms through the later half of the upcoming week. The NAM is just about 12-24h faster thru its 84h forecast ending Wednesday. Glass && .AVIATION: (For the 18z TAFs through 18z Monday Afternoon) Issued at 1249 PM CDT Sun Jun 22 2014 Scattered thunderstorms are the primary concern this afternoon. Greater coverage should be across the eastern Ozarks and northeast Missouri/west central Illinois this afternoon. Unfortunately, there`s little forcing in the atmosphere today to latch on to and try to figure timing at any given TAF site. This will definitely be a reactionary afternoon of updating forecasts as thunderstorm cells pop up. VFR flight conditions will prevail outside of storms. Storms should diminish after sunset. A weak trof of low pressure will move into the area on Monday. Expect more widespread showers and thunderstorms to develop and overspread the area from late morning into Monday afternoon. Specifics for KSTL: Scattered thunderstorms are the primary concern this afternoon. Unfortunately, there`s little forcing in the atmosphere today to latch on to and try to figure timing at Lambert. This will definitely be a reactionary afternoon of updating forecasts as thunderstorm cells pop up. VFR flight conditions will prevail outside of storms. Storms should diminish after sunset. A weak trof of low pressure will move into the area on Monday. Expect more widespread showers and thunderstorms to develop and overspread the area from late morning into Monday afternoon. Carney && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
606 AM CDT Sun Jun 22 2014 .SHORT TERM: (Through Late This Afternoon) Issued at 336 AM CDT Sun Jun 22 2014 Once again the main forecast issue is thunderstorm chances. The only ongoing precipitation early this morning is a shrinking area of showers in Pike Co MO. This originated from a NW-SE cluster of thunderstorms which occurred just north of Mexico in response to lift via a weak westerly LLJ along the cool side of a large scale outflow boundary. That boundary remains somewhat identifiable from far southern IL into central/NW MO. While there is no clear cut model solution, there are suggestions by the deterministic guidance which are supported by recent runs of the HRRR and the 4km NSSL WRF that this confluent zone from central through southeast MO will be the region of scattered thunderstorm development beginning near midday, with activity shifting east thru the afternoon. There may be a region of somewhat greater coverage and organization across northeast Missouri and west central IL resulting from an eastward migrating vort max which is now present in the central Plains. Highs once again look seasonable in the upper 80s to lower 90s. Glass .LONG TERM: (Tonight through Saturday) Issued at 336 AM CDT Sun Jun 22 2014 The greatest threat of thunderstorms tonight should also reside across the northern portion of the CWA where the consensus of the model QPFs have the highest coverage. This appears reasonable as a cold front will be pushing into IA and NW MO in association with a much better defined slowly progressive short wave trof and attendant vort maxes. Strengthening and veering wind fields and a stronger veering WSW LLJ should result in good eastward progression of organized convection. The cold front will move slowly across the area Monday and Monday night and should be accompanied by fairly widespread showers and thunderstorms. The models vary on how far south the front will push on Tuesday with the NAM showing the least progression only into southern IL and southern MO while the GFS and SREF push the front into AR. Eventually the front will retreat back northward and be the focus for additional showers and thunderstorms through the later half of the upcoming week. The NAM is just about 12-24h faster thru its 84h forecast ending Wednesday. Glass && .AVIATION: (For the 12z TAFs through 12z Monday Morning) Issued at 557 AM CDT Sun Jun 22 2014 A hot and humid air mass with plenty of leftover outflow boundaries will support yet another day of low-predictability scattered afternoon/evening thunderstorms. Widespread precipitation is expected just beyond the end of the 24hr TAF period. Specifics for KSTL: A hot and humid air mass with plenty of leftover outflow boundaries will support yet another day of low-predictability scattered afternoon/evening thunderstorms. Widespread precipitation is expected near the end of the 30hr TAF period (primarily after 23/12z) due to the approach of a cold front and an upper level disturbance. Kanofsky && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
400 AM CDT Sun Jun 22 2014 .SHORT TERM: (Through Late This Afternoon) Issued at 336 AM CDT Sun Jun 22 2014 Once again the main forecast issue is thunderstorm chances. The only ongoing precipitation early this morning is a shrinking area of showers in Pike Co MO. This originated from a NW-SE cluster of thunderstorms which occured just north of Mexico in response to lift via a weak westerly LLJ along the cool side of a large scale outflow boundary. That boundary remains somewhat identifiable from far southern IL into central/NW MO. While there is no clear cut model solution, there are suggestions by the deterministic guidance which are supported by recent runs of the HRRR and the 4km NSSL WRF that this confluent zone from central through southeast MO will be the region of scattered thunderstorm development beginning near midday, with activity shifting east thru the afternoon. There may be a region of somewhat greater coverage and organization across northeast Missouri and west central IL resulting from an eastward migrating vort max which is now present in the central Plains. Highs once again look seasonable in the upper 80s to lower 90s. Glass .LONG TERM: (Tonight through Saturday) Issued at 336 AM CDT Sun Jun 22 2014 The greatest threat of thunderstorms tonight should also reside across the northern portion of the CWA where the consensus of the model QPFs have the highest coverage. This appears reasonable as a cold front will be pushing into IA and NW MO in association with a much better defined slowly progressive short wave trof and attendant vort maxes. Strengthening and veering wind fields and a stronger veering WSW LLJ should result in good eastward progression of organized convection. The cold front will move slowly across the area Monday and Monday night and should be accompanied by fairly widespread showers and thunderstorms. The models vary on how far south the front will push on Tuesday with the NAM showing the least progression only into southern IL and southern MO while the GFS and SREF push the front into AR. Eventually the front will retreat back northward and be the focus for additional showers and thunderstorms through the later half of the upcoming week. The NAM is just about 12-24h faster thru its 84h forecast ending Wednesday. Glass && .AVIATION: (For the 06z TAFs through 06z Sunday Night) Issued at 1031 PM CDT Sat Jun 21 2014 Most of the convection across the area should dissipate by 06z Sunday with only high level convective debris cloudiness remaining late tonight which should thin out. There may be some fog late tonight/early Sunday morning due to the recent rainfall and as the surface wind becomes light. Diurnal cumulus clouds will develop again late Sunday morning and afternoon with at least widely scattered showers/storms expected Sunday afternoon into the evening. Surface winds should be mainly s-swly on Sunday, then weaken Sunday evening. Specifics for KSTL: Lingering thundershowers should dissipate or shift southeast of STL by 06z Sunday. After this mainly just thinning high level convective debris clouds late tonight along with the surface wind becoming light. Diurnal cumulus clouds will develop again late Sunday morning and afternoon with at least widely scattered showers/storms Sunday afternoon into the evening. Light surface wind will become s-swly Sunday afternoon, then weaken again Sunday evening. GKS && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1202 AM CDT Sun Jun 22 2014 .UPDATE: Issued at 1159 PM CDT Sat Jun 21 2014 While remnants of evening storms dissipate fairly rapidly from southeast Missouri into southwest Illinois, spotty convection continues to linger north of COU. Given the somewhat persistent and stubborn nature of this activity, am beginning to wonder if some low chance of storms wont persist throughout the night over our western areas, as very weak WAA of resdiually unstable air overruns the rain-cooled airmass, and produces just enough lift to generate spotty convection. Lastest RUC forecasts are certainly suggesting this, with even the 12z NCEP 4km at least hinting in this direction. So, update will be issued shortly which continues low PoPs from central into ne MO and west central IL during the overnight hours. Truett && .SHORT TERM: (Through Late Tonight) Issued at 322 PM CDT Sat Jun 21 2014 Thunderstorm trends remain the primary focus of the short term forecast. Expecting storms up over northeast MO and west central IL to become more widespread through boundary interactions and collisions. Airmass is very unstable with SBCAPE in excess of 4500 J/kg and SB-LIs of -9 to -10 all the way back into central and east central MO. Expect that outflows from the storms up north will propagate southward which will provide triggers for further development. Storms could form into clusters or perhaps even a broken line before dissipating this evening, most likely somewhere near or just south of the Missouri River. There may be some patchy fog late tonight in any areas that receive rain this evening, but have left mention out for now due to the potentially patchy nature of the rain. Temperatures tonight should be similar to what we experienced last night so used a blend of guidance and persistence for lows tonight. Carney .LONG TERM: (Sunday through Next Saturday) Issued at 322 PM CDT Sat Jun 21 2014 The current pattern we are in will continue relatively unaltered through late Thursday, with a flat west-east mid-level flow and periodic effects from upper level disturbances or MCVs. This alludes to a continuation of our unsettled wx and TSRA chances thru much of this period, only being limited when available moisture becomes a factor, or enhanced when a clear focus can be seen. Rich atmospheric moisture will continue in place over our region into Monday night, with PWs in excess of 1.5", tailing off a bit on Tuesday and Wednesday, and returning for Thursday. With that in mind, a similar setup will be found Sunday that we have had the past few days for most locations, with weak boundaries, very weak CINH and hi instability during the peak heating times, which then fade with sunset. Some enhanced PoPs were maintained in northeast MO for late afternoon with influences from the southern periphery of the MCV du jour which is expected to be centered in IA at that time, but by and large, the convection looks to be pretty random, forming where enough local convergence can occur to initiate and will be hard to detect until we get closer. Better chances for SHRA/TSRA are expected on Monday and Monday night with a more significant shortwave TROF that will pass into this convectively favorable atmosphere--and went likely PoPs as a result. Tuesday and Wednesday, at this time, look to be a couple of dry days for most areas, but an intrusion from a strong enough upper level disturbance would change that. Rain chances return for a widespread area on Thursday with the return of rich and deep moisture and another upper level shortwave. A deep and amplified upper TROF is then expected to dig into the western CONUS for the end of the week. The models diverge on what this means for our area, but they do agree on rising heights and upper ridging returning, but aren`t as sure on if that will be accompanied by upper level disturbances or not. At this point, felt prudent to fall back to climo PoPs in most places given the model impasse. Temps will remain relatively unchanged the next seven days with temps at or a bit above normal, with Monday looking like the only day where some areas may see below normal temps depending on how fast the clouds and rain move in. TES && .AVIATION: (For the 06z TAFs through 06z Sunday Night) Issued at 1031 PM CDT Sat Jun 21 2014 Most of the convection across the area should dissipate by 06z Sunday with only high level convective debris cloudiness remaining late tonight which should thin out. There may be some fog late tonight/early Sunday morning due to the recent rainfall and as the surface wind becomes light. Diurnal cumulus clouds will develop again late Sunday morning and afternoon with at least widely scattered showers/storms expected Sunday afternoon into the evening. Surface winds should be mainly s-swly on Sunday, then weaken Sunday evening. Specifics for KSTL: Lingering thundershowers should dissipate or shift southeast of STL by 06z Sunday. After this mainly just thinning high level convective debris clouds late tonight along with the surface wind becoming light. Diurnal cumulus clouds will develop again late Sunday morning and afternoon with at least widely scattered showers/storms Sunday afternoon into the evening. Light surface wind will become s-swly Sunday afternoon, then weaken again Sunday evening. GKS && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1147 PM CDT Sat Jun 21 2014 .DISCUSSION... Issued at 359 PM CDT SAT JUN 21 2014 What else would one expect for the official first day of summer other than an uncapped tropical airmass defined by high CAPEs and weak shear with isolated convection along weak boundaries. Very weak and isolated convection continues to sputter across northern MO this afternoon in a region of weak h8 convergence. Increasing convection is noted in a region of moderate h8 moisture convergence which extends southwest from west central IL cluster into the east central CWA. HRRR has been picking out this general area for most of today. Will focus higher PoPs for the late afternoon and early evening hours this area. A small MCV over south central NE left over from earlier convection is drifting east towards slightly higher MLCAPEs around 2000 J/kg. Will insert low chance PoPs for this evening for nw and north central MO for possible convective development. Last several runs of the HRRR generates scattered convection this area. Expect another complex convective scenario tonight. Current convection over the NE Panhandle may eventually merge with another nocturnal MCS that rolls off the CO Front Range and heads east. Will throw in some PoPs over northwest MO towards Sunday morning to cover the possibility of a dying MCS reaching the CWA. Continued very warm and humid on Sunday with above average temperatures. Low confidence on placement of PoPs as any outflow boundaries left over from tonight`s convection will play a key role. Sunday night into Monday still holds the highest PoPs during this forecast period. While the models have started to diverge on where another nocturnal MCS will track there is good consensus that a cold front moving southeast through NE/IA/KS will play a pivotal role. Have had to lower qpf during this period as confidence on a large MCS moving through the CWA has diminished. But should see good coverage of convection with the front. High precipitable water values are a concern should storms crawl through or back build along the front. So, later forecasts may need to ramp qpf back up. While Tuesday looks dry and a tad cooler behind the front weak embedded disturbances within the quasi-zonal pattern will provide a lot of uncertainty on timing and location of any convection for Wednesday/Wednesday night. The upper pattern evolves for the latter half of the week as an upper trough pushes through the intermountain region. The backing flow downstream will enable a southwesterly fetch to spread through the Central Plains and Mid MO Valley. Should see a slight uptick in temperatures and humidity with warmer air aloft spreading into the CWA and forcing any convection to become elevated and more nocturnal. && .AVIATION...(For the 06Z TAFS through 06Z Sunday Night) Issued at 1147 PM CDT SAT JUN 21 2014 VFR conditions are likely to occur for the entire forecast with generally light southerly winds. Forecast soundings cotninue to show a nearly to fully uncapped environment tomorrow afternoon with what should be a multitude of remnant boundaries for storms to possibly develop on. Have added a VCTS group for the afternoon given this possibility. Of greater likelihood to impact the terminals is the potential for more widespread storms to move through very late in the forecast. There is a significant amount of uncertainty with the timing of this ranging from around 00Z Monday to after 06Z Monday. Given this, will just keep the VCTS group through the end of the forecast as the potential from afternoon storms may evolve into the potential for more widespread evening/overnight storms. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ DISCUSSION...MJ AVIATION...CDB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
341 PM CDT SUN JUN 22 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 341 PM CDT SUN JUN 22 2014 AT 19Z...WATER VAPOR SHOWED QUASI-ZONAL FLOW ACROSS MUCH OF THE CONUS WITH AN UPPER LEVEL LOW SPINNING OVER THE CENTRAL SASKATCHEWAN/MANITOBA BORDER. MULTIPLE WEAK SHORTWAVES COULD BE PICKED OUT MOVING ACROSS THE ROCKIES...FROM MONTANA DOWN THROUGH NEW MEXICO. THE STRONGER SHORTWAVE WAS SEEN OVER WESTERN COLORADO AT MID AFTERNOON WHICH WILL IMPACT THE FORECAST FOR TONIGHT...WITH THE SECOND MORE DISTINCT SHORTWAVE SEEN OVER EASTERN IDAHO...WHICH WILL IMPACT THE FORECAST FOR MONDAY. AT THE SURFACE...A COLD FRONT WAS SITUATED FROM SOUTHWEST KANSAS INTO NORTHWEST MISSOURI. NORTH OF THIS FRONT COLD AIR HAD ADVECTED INTO NEBRASKA...WITH MID AFTERNOON TEMPERATURES GENERALLY IN THE 70S AND LOW 80S. DECENT LOW LEVEL MOISTURE DID REMAIN IN PLACE...AS DEWPOINTS ACROSS THE AREA WERE STILL IN THE UPPER 50S AND 60S. WITH THE MOISTURE IN PLACE AND STEEP LOW LEVEL LAPSE RATES...AN EXTENSIVE CUMULUS FIELD HAD DEVELOPED ACROSS WESTERN NEBRASKA. DESPITE DECENT SB INSTABILITY OF 1500-2500 J/KG WITH NO CAP...ANY SHOWERS AND THUNDERSTORMS HAVE HAD A PROBLEM MAINTAINING WITH NO ADDITIONAL FORCING IN PLACE. FOR THIS EVENING AND TONIGHT...ALTHOUGH THE HRRR IS INDICATING STORMS DEVELOPING OVER SOUTHWEST NEBRASKA AHEAD OF THE MAIN SYSTEM OVER THE ROCKIES...FEEL THIS ACTIVITY WILL BE WEAK WITH THE LACK OF FORCING FROM THE SHORTWAVE AND VERY LITTLE IF ANY FORCING COMING FROM ANY LOW LEVEL MOISTURE TRANSPORT. SO WILL FOCUS ON ACTIVITY MOVING OUT ONTO THE PLAINS WITH THE MAIN SHORTWAVE. AS THIS SHORTWAVE OVER WESTERN COLORADO MOVES EAST EXPECT FURTHER DEVELOPMENT OF CONVECTION ALONG THE FOOTHILLS AND INTO THE HIGH PLAINS. THE QUESTION WILL BE HOW FAR NORTH THE CONVECTION WILL DEVELOP. THE LATEST FEW RUNS OF THE HRRR INDICATE ACTIVITY DEVELOPING AS FAR NORTH AS SCOTTSBLUFF. THESE STORMS WOULD THEN MOVE SOUTHEAST ALONG A THETA-E GRADIENT. ALTHOUGH THERE IS SUFFICIENT INSTABILITY AND DEEP LAYER SHEAR WILL BE INCREASING...THE LOCAL AREA WILL BE ON THE NORTHERN FRINGE OF ANY ACTIVITY AND WITH THE BETTER FORCING OVER KANSAS EXPECT THE THREAT FOR ANY SEVERE STORMS TO STAY SOUTH OF THE AREA. FOR MONDAY THE SHORTWAVE TROUGH NOW OVER EASTERN IDAHO WILL MOVE ACROSS WYOMING AND THEN ACROSS NEBRASKA FROM NORTHWEST TO SOUTHEAST. NOT EXTREMELY CONFIDENT ON HOW MUCH COVERAGE OF SHOWERS AND THUNDERSTORMS THERE WILL BE AS THE AIRMASS WILL BE SLIGHTLY DRIER...WITH DEWPOINTS MAINLY IN THE 50S AND NO REAL SURGE OF DEEP MOISTURE ALOFT. AT THE PRESENT TIME THINK ANY CONVECTION WILL BE MORE ISOLATED TO SCATTERED IN NATURE. THE NEXT QUESTION IS WHERE THE CONVECTION WILL ACTUALLY BE. THE NAM SHOWS QPF ACROSS MUCH OF THE FORECAST AREA WHILE THE GFS/ECMWF ARE KEEPING IT MAINLY OVER THE PANHANDLE AND SOUTHWEST NEBRASKA. HAVE SIDED WITH THE GFS/ECMWF FOR TODAY AND HAVE LIMITED CHANCES FOR THE WESTERN AREAS. AS FOR HIGHS ON MONDAY...LOOKING FOR A SLIGHTLY COOLER DAY WITH HIGHS IN THE 70S AND LOW 80S AS COOLER AIR SLOWLY CONTINUES TO FILTER INTO THE AREA BEHIND THE UPPER LEVEL SYSTEM OVER SOUTHERN CANADA. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 341 PM CDT SUN JUN 22 2014 NORTHWEST FLOW ALOFT WILL PERSIST MONDAY NIGHT THROUGH TUESDAY NIGHT WITH THE PASSAGE OF TWO DISTINCT DISTURBANCES. MAINTAINED 30 POPS LATE MONDAY NIGHT ACROSS WESTERN ZONES...TO 40 POPS TUESDAY/TUESDAY NIGHT. PWAT VALUES FROM GFS INDICATE 120 TO NEAR 140 PERCENT OF NORMAL WITH DEEP LAYER SHEAR INCREASING TO 30 TO 40 KTS. THIS SUPPORTIVE OF STRONG THUNDERSTORMS TUESDAY AFTN/EVENING WITH LOCALLY HEAVY RAINFALL DUE TO SLOW STORM MOTION NEAR 10 KTS. SECOND DISTURBANCE FORECAST TO LIFT ACROSS LATE TUESDAY NIGHT AND WEDNESDAY WITH 40 POPS TUESDAY NIGHT...FOLLOWED BY 40 POPS FOR NCTRL WEDNESDAY. MAINLY 20 TO 30 POPS THURSDAY THROUGH SATURDAY. DUE TO WEAK RIDGING OVER THE REGION AND SWRLY FLOW TO OUR WEST WHICH MOVES IN BY FRIDAY NIGHT...MODEL AGREEMENT IN TIMING AND LOCATION IS RATHER POOR. TEMPERATURES HOWEVER WILL WARM FROM THE UPPER 70S TO LOWER 80S TUESDAY...MID 80S THURSDAY THROUGH SATURDAY TO AROUND 90 BY SUNDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1246 PM CDT SUN JUN 22 2014 PLENTIFUL CLOUD COVER IS EXPECTED ACROSS WESTERN AND NORTH CENTRAL NEBRASKA THROUGH MONDAY AFTERNOON AS MULTIPLE WEAK SYSTEMS CROSS THE ROCKIES TO BRING MOISTURE INTO THE REGION. CEILINGS ARE EXPECTED TO STAY VFR THROUGH THIS FORECAST PERIOD THOUGH. THERE IS A CHANCE FOR THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS MUCH OF THE AREA...HOWEVER COVERAGE IS EXPECTED TO BE ISOLATED TO SCATTERED. HAVE THE MENTION OF VCTS AT KLBF AS THE HIGHER PROBABILITIES FOR STORMS LATER THIS AFTERNOON AND EVENING WILL BE ACROSS SOUTHWEST NEBRASKA. CONFIDENCE ON ANY MOVING ACROSS THE KVTN TERMINAL IS LOW SO HAVE NOT INCLUDED THUNDER MENTION IN THE FORECAST AT THAT LOCATION. ANOTHER SYSTEM DOES LOOK TO CROSS NEBRASKA ON MONDAY...BUT TIMING INTO THE TAF SITES WOULD LIKELY BE LATE IN THE PERIOD OR POSSIBLY AFTER 18Z...IF ACTIVITY DOES IN FACT DEVELOP. LOW CONFIDENCE IN THIS SCENARIO CURRENTLY SO A QUIET FORECAST IS ONGOING CURRENTLY FOR MONDAY. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BROOKS LONG TERM...ROBERG AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
309 PM CDT SUN JUN 22 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 301 PM CDT SUN JUN 22 2014 THE PRIMARY SHORT TERM FORECAST CONCERN CENTERS AROUND THE CHANCE OF THUNDERSTORMS THIS AFTERNOON INTO TONIGHT. OVER THE LAST 8 HOURS HAVE GREATLY REDUCED THUNDERSTORM CHANCES FOR THIS AFTERNOON AND TONIGHT ACROSS OUR FORECAST AREA. THE GREATEST REDUCTION IN THUNDERSTORM CHANCES HAS BEEN ACROSS NEBRASKA. THERE IS MODEST TO EVEN FAIRLY GOOD INSTABILITY ACROSS THE FORECAST AREA ESPECIALLY ACROSS KANSAS...WITH LITTLE TO NO CIN. WIND SHEAR IS RATHER WEAK WITH DEEP LAYER 0-6 KM SHEAR OF LESS THAN 30 KTS. THE BIG ISSUE CENTERS AROUND FORCING OR THE LIFTING MECHANISM FOR ORGANIZED CONVECTION. FORCING MECHANISMS ACROSS THE REGION INCLUDE AN UPPER LEVEL SHORT WAVE TROUGH OVER IOWA...A SOUTHWARD SLIPPING SFC FRONTAL BOUNDARY ACROSS NORTHERN KANSAS...AND A VERY WEAK UPPER WAVE CENTERED OVER THE BLACK HILLS OF SOUTH DAKOTA EXTENDING INTO THE NEBRASKA PANHANDLE. THE SFC FRONT IS THE PRIMARY FORCING MECHANISM CURRENTLY LOCATED OVER OUR FORECAST AREA AND IT IS GRADUALLY SINKING SOUTH WHERE IT WILL EXIT OUR AREA BY LATER THIS EVENING. THEREFORE...THUNDERSTORMS SEEM MOST LIKELY LATE THIS AFTERNOON INTO EARLY THIS EVENING IN CLOSE PROXIMITY TO THE SFC FRONT OVER NORTHERN KANSAS AND THUS HAVE KEPT POPS AROUND 50/50 IN THESE SOUTHERN ZONES...WITH THE HIGHER POPS REALLY BEING SOUTH OF OUR FORECAST AREA TONIGHT. SOME FORECAST MODELS GENERATE CONVECTION ACROSS THE HIGH PLAINS TONIGHT IN ASSOCIATION WITH THE VERY WEAK UPPER WAVE...BUT 4 OUT OF 6 MODELS HAVE THIS PRECIPITATION DIEING OFF BEFORE REALLY REACHING OUR AREA TONIGHT. ONE OUTSIDE WRF RUN AND THE HRRR DO BRING CONVECTION FROM WESTERN PORTIONS OF NEBRASKA AND KANSAS INTO OUR FORECAST AREA LATE TONIGHT WHILE MOST MODELS DO NOT. WILL GO WITH THE MAJORITY GIVEN THERE IS NOT MUCH OF A LOW LEVEL JET TO HELP SUSTAIN CONVECTION TONIGHT ACROSS OUR FORECAST AREA. ANY THUNDERSTORMS THAT CAN FORM THIS AFTERNOON OR EVENING ACROSS KANSAS COULD BECOME SEVERE GIVEN THE HIGHER INSTABILITY ACROSS OUR SOUTHERN ZONES. MONDAY...MOST FORECAST MODELS INDICATE THAT WE WILL BE IN BETWEEN WEAK SHORT WAVE STORM SYSTEMS AND LIKELY DRY. TEMPERATURES WILL BE MILD WITH A LIGHT NORTHEAST WIND KEEPING THINGS A BIT COOLER THAN TODAY. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 301 PM CDT SUN JUN 22 2014 THE WEATHER PATTERN REMAINS UNSETTLED DURING THE EXTENDED PERIODS WITH INTERMITTENT CHANCES FOR THUNDERSTORMS. AN UPPER LOW PRESSURE SYSTEM WILL BE TRANSLATING SOUTHEAST FM CANADA TO THE UPPER MIDWEST REGION AT THE ONSET OF THE EXTENDED WITH THE FLOW ALOFT TRANSITIONING WEST NORTHWEST FOR A TIME AS ANOTHER TROUGH DIGS INTO THE PACIFIC NORTHWEST REGION. A SERIES OF WAVES EMBEDDED IN THE FLOW WILL AID IN TSTM DEVELOPMENT WITH TIMING/PLACEMENT DEPENDENT UPON WAVE TIMING AND BOUNDARY LOCATIONS AND BOUNDARY LOCATION WILL BE DEPENDENT UPON HOW CONVECTION UNFOLDS THE PREVIOUS DAY. IT IS DIFFICULT TO PINPOINT DETAILS ATTM AND WITH THE PROGRESSIVE PATTERN JUST CANNOT RULE OUT TSTM CHCS NEARLY EVERY DAY. CONVECTION MAY DEVELOP ALONG THE HIGH PLAINS AND ROLL EASTWARD...OR MAY INITIATE ALONG A BOUNDARY WITHIN THE AREA. SREF INSTABILITY PROGS INDICATE THE GREATER INSTABILITY MONDAY NIGHT WILL RESIDE ALONG THE HIGH PLAINS REGION...WHICH WILL BEGIN TO SPREAD EASTWARD ON TUESDAY...WITH MUCAPES INCREASING TO NEAR OR JUST ABOVE 1000 J/KG. WITH THE MORE MARGINAL INSTABILITY ON TUESDAY...NOT LOOKING FOR MUCH SEVERE WX JUST YET WITH INSTABILITY FURTHER INCREASING TUESDAY NIGHT INTO MID WEEK WITH RETURN FLOW...STRENGTHENING NOCTURNAL LLVL JET AND WAA/UPPER RIDGING AHEAD OF UPPER TROUGH IN THE PACIFIC NW. UPPER RIDGING SETTLES OVERHEAD FOR THE LATTER PART OF THE WORKWEEK AND MID LEVEL TEMPS INCREASE TO AROUND 14C SO CAP MAY LIMIT CONVECTION FOR A TIME. MODELS ARE NOT IN GREAT AGREEMENT ON THE TIMING/PROGRESSION OF THE WESTERN TROUGH AS IT PUSHES EAST THRU THE MOUNTAINS TOWARDS THE PLAINS AND WILL NEED TO MONITOR BUT CHCS FOR STORMS INCREASE AGAIN WITH THIS SYSTEM OVER THE WEEKEND OR EARLY NEXT WEEK. ALL BEING SAID...INTERMITTENT CHANCES FOR STORMS CONTINUE AND TEMPS LOOK FAIRLY SEASONAL ATTM. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 104 PM CDT SUN JUN 22 2014 REDUCED THUNDERSTORM CHANCES EVEN FURTHER WITH LATEST UPDATE BASED ON LATEST FORECAST MODEL RUNS. THE CHANCE OF THUNDERSTORMS AT KGRI IS NOW AROUND 30 PERCENT AT ITS HIGHEST POINT AND THIS MAY BE ON THE HIGH SIDE. THEREFORE...HAVE ELECTED TO REMOVE MENTION OF VICINITY THUNDERSTORMS FROM THE TAF. THE WIND WILL BE LIGHT AND GENERALLY OUT OF THE NORTH BEHIND THE FRONT TODAY AND TOMORROW...ALTHOUGH IT COULD BE A BIT VARIABLE TONIGHT. VFR SKY AND VISIBILITY CONDITIONS ARE EXPECTED. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...WESELY LONG TERM...FAY AVIATION...WESELY
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1247 PM CDT SUN JUN 22 2014 .UPDATE... ISSUED AT 1048 AM CDT SUN JUN 22 2014 THE FORECAST WAS UPDATED FOR PRECIPITATION AND WEATHER FOR TODAY. PARTLY TO MOSTLY SUNNY SKIES ARE CURRENTLY BEING OBSERVED. THE RAIN OVER THE NORTHEAST PART OF THE FORECAST AREA HAS MOVED EAST OF THE AREA. WITH THE EXCEPTION OF A FEW WEAK RADAR ECHOES THAT HAVE MOVED ACROSS NORTHERN SHERIDAN COUNTY...THE SHOWERS AND ISOLATED THUNDERSTORMS OVER SOUTH DAKOTA HAVE STAYED NORTH OF THE FORECAST AREA. THE HRRR HAS BEEN HANDLING THIS ACTIVITY FAIRLY WELL...HAVING IT MOVE STRAIGHT EAST RATHER THAN DIPPING SOUTH AS HAD BEEN PREVIOUSLY FORECAST. DUE TO THESE TRENDS...CHANCES HAVE BEEN REMOVED FOR MOST PLACES THROUGH THE MORNING HOURS. THERE IS SOME INSTABILITY ACROSS THE AREA...IN THE ORDER OF 500-1500 J/KG SB CAPE ACCORDING TO THE SPC MESOANALYST PAGE AT 1530Z. THIS SHOULD STAY FAIRLY STABLE THROUGH THE AFTERNOON. THERE WILL BE A LACK OF FORCING THOUGH THIS AFTERNOON AS SHORTWAVES ARE LOOKING TO MOVE ACROSS SOUTH DAKOTA...AND THEN OUT OF COLORADO AND INTO KANSAS LATER IN THE DAY. FEEL THAT THERE MAY BE SOME ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS...BUT WITH THE LACK OF FORCING ACTIVITY SHOULDN/T BE WIDESPREAD SO HAVE LOWERED THE COVERAGE OF STORMS IN THE FORECAST FOR THIS AFTERNOON. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT SUN JUN 22 2014 OUTFLOW DOMINANT TSTMS CONTINUE TO DEVELOP PRODUCING LOCALLY HEAVY RAINFALL THIS MORNING. STORM DEVELOPMENT IS BEING AIDED BY MODEST MOISTURE ADVECTION AS SHOWN BY THE RAP MODEL AND NOCTURNAL COOLING IN THE MID LEVELS OF THE ATMOSPHERE. THE RAP SHOWS THIS MOISTURE TRANSPORT SHIFTING OFF EAST OF THE FCST AREA TOWARD 12Z WITH THE HEAVY RAIN BECOMING LIGHT TO MODERATE. THE ATMOSPHERE IS EXPECTED TO BECOME UNSTABLE THIS AFTERNOON WITH CONVECTION REDEVELOPING BUT NOT NEARLY AS UNSTABLE AS IT IS NOW. SCATTERED POPS ARE IN PLACE FOR THE AFTERNOON HOURS WHICH BECOME ISOLATED TONIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 345 AM CDT SUN JUN 22 2014 MONDAY AND BEYOND. ACTIVE PATTERN TO CONTINUE THROUGH MUCH OF THE EXTENDED AS PLENTIFUL GULF MOISTURE WORKS WITH A NORTHWARD RETREATING FRONTAL BOUNDARY AND PERIODIC WEAK IMPULSES PASSING THROUGH THE WESTERLIES IN QUASI ZONAL FLOW...THUS...NEAR DAILY/NIGHTLY THUNDERSTORMS CHANCES TO REMAIN IN THE EXTENDED FORECAST. LOOKING TO LATE WEEK...THE SYNOPTIC SCALE FLOW ACROSS THE CENTRAL/NORTHERN PLAINS APPEARS TO UNDERGO A TRANSITION AS THERE REMAINS STRONG AGREEMENT OF THE DEVELOPMENT OF A SIGNIFICANT UPPER TROUGH OVER THE WESTERN CONUS. LOW AMPLITUDE TRANSITORY RIDGING THURSDAY MAY PROVIDE FOR A BRIEF DRY PERIOD...BUT PRECIPITATION CHANCES RAMP BACK UP WITH THE APPROACH OF WEAK SHORTWAVES FROM THE WESTERN CONUS TROUGH LATE WEEK AND NEXT WEEKEND. FOR THE DAILY DETAILS...DRIER AIR TO WORK ACROSS WESTERN AND NORTH CENTRAL NEBRASKA ON MONDAY...WITH PLEASANT CONDITIONS ANTICIPATED FOR MOST IF NOT ALL OF THE CWA. THE EXCEPTION BEING WHERE WEAK UPSLOPE FLOW AND THE PASSAGE OF THE NEXT SUBTLE WAVE MAY PROVIDE FOR A FEW STORMS MONDAY EVENING AND THROUGH THE OVERNIGHT ACROSS THE HIGHER TERRAIN OF WESTERN NEBRASKA. WILL MAINTAIN SLIGHT CHANCE POPS IN THIS AREA...BUT EXPECT MOST OF THE ACTIVITY TO BE TIED TO THE HIGHER TERRAIN WEST OF THE CWA. A MORE NOTABLE WAVE ARRIVES ON TUESDAY WHEN THE AFOREMENTIONED FRONT LIFTS NORTH ACROSS THE AREA. WITH RETURN SOUTHERLY FLOW IN PLACE...MOISTURE WILL BE AVAILABLE FOR STORMS...POSSIBLY WIDESPREAD WITH HEAVY RAINFALL. THIS ACTIVITY WILL SPREAD EAST THROUGH THE DAY...WITH ADDITIONAL STORMS POSSIBLE OVERNIGHT WITH THE DEVELOPMENT OF A WEAK TO MODERATE HIGH PLAINS LLJ. TIMING AND LOCATION OF THE PROJECTED CONVECTION AND/OR COMPLEXES IS NOT READILY APPARENT ATTM...SO WILL GENERALLY BROADBRUSH 30-40% POPS MOVING WEST TO EAST ACROSS THE ENTIRE CWA TUESDAY THROUGH EARLY WEDNESDAY MORNING. ADDITIONAL STORMS WILL BE POSSIBLE WEDNESDAY AS THE ATMOSPHERE REMAINS UNSTABLE WITH A FRONT IN THE REGION AND ANOTHER SUBTLE WAVE PASSAGE. LIKEWISE...WIDESPREAD 30-40% POPS WEDNESDAY INTO EARLY THURSDAY ARE WARRANTED. FOR LATE THURSDAY THROUGH THE UPCOMING WEEKEND...MOST OF THE UPPER ENERGY IS SHOWN TO BE DIRECTED TO THE WEST AND NORTH OF THE CWA...BUT THERE STILL REMAINS STRONG SUPPORT OF WAVE IMPACTING THE CWA FRIDAY NIGHT INTO SATURDAY. THE CR ALLBLEND INT GENERATED CHANCE POPS FOR MUCH OF THE CWA...GIVEN THIS SUPPORT...SEE NO REASON TO DEVIATE FROM THE PROCEDURE ATTM. TEMPERATURES THROUGH THE EXTEND PERIODS WILL UNDERGO A SLIGHT WARMING TREND WITH HIGHS GENERALLY IN THE UPPER 70S TO LOWER 80S ON MONDAY...BUT RISE INTO THE MID TO UPPER 80S BY FRIDAY. A FEW LOWER 90S MAY BE POSSIBLE SOUTH OF THE INTERSTATE LATE WEEK AS DEVELOPING SURFACE LOW DIRECTS AN AIRMASS FROM THE DESERT SW INTO WESTERN NEBRASKA. LOWS TO REMAIN SEASONAL THROUGH THE EXTENDED FORECAST PERIODS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1246 PM CDT SUN JUN 22 2014 PLENTIFUL CLOUD COVER IS EXPECTED ACROSS WESTERN AND NORTH CENTRAL NEBRASKA THROUGH MONDAY AFTERNOON AS MULTIPLE WEAK SYSTEMS CROSS THE ROCKIES TO BRING MOISTURE INTO THE REGION. CEILINGS ARE EXPECTED TO STAY VFR THROUGH THIS FORECAST PERIOD THOUGH. THERE IS A CHANCE FOR THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS MUCH OF THE AREA...HOWEVER COVERAGE IS EXPECTED TO BE ISOLATED TO SCATTERED. HAVE THE MENTION OF VCTS AT KLBF AS THE HIGHER PROBABILITIES FOR STORMS LATER THIS AFTERNOON AND EVENING WILL BE ACROSS SOUTHWEST NEBRASKA. CONFIDENCE ON ANY MOVING ACROSS THE KVTN TERMINAL IS LOW SO HAVE NOT INCLUDED THUNDER MENTION IN THE FORECAST AT THAT LOCATION. ANOTHER SYSTEM DOES LOOK TO CROSS NEBRASKA ON MONDAY...BUT TIMING INTO THE TAF SITES WOULD LIKELY BE LATE IN THE PERIOD OR POSSIBLY AFTER 18Z...IF ACTIVITY DOES IN FACT DEVELOP. LOW CONFIDENCE IN THIS SCENARIO CURRENTLY SO A QUIET FORECAST IS ONGOING CURRENTLY FOR MONDAY. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...BROOKS SHORT TERM...CDC LONG TERM...JACOBS AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1217 PM CDT SUN JUN 22 2014 .UPDATE... ISSUED AT 1214 PM CDT SUN JUN 22 2014 SEVERAL MINOR CHANGES WERE MADE TO TODAY MAINLY TO LOWER MAX TEMPS A BIT NERN ZONES WHERE RESIDUAL CLOUDS WHERE DECREASED COVERAGE OF MORNING PRECIP WILL LIKELY HAVE LARGEST IMPACT. STRONG THUNDERSTORMS FAR SERN NEBR WILL BE EXITING SHORTLY AND AMOUNT OF ATMOSPHERIC RECOVERY REMAINS QUESTIONABLE ON BACK SIDE OF MCV. HOWEVER...SOME POPS STILL WARRANTED AS SOME HEATING/RECOVERY WILL OCCUR. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 234 AM CDT SUN JUN 22 2014 MOSAIC RADAR IMAGERY THIS MORNING SHOWING TWO DISTINCT CLUSTER OF TSTMS...ONE OVER ERN SD ASSOCIATED WITH A SEWD BOUND COLD FRONT/MID LYR UPGLIDE. OTHER ONE WAS SITUATED ALONG INVERTED SFC TROF/THERMAL BNDRY EXTENDING FROM NW KS INTO S-CNTRL NEB WITHIN AREA OF MID LYR QG FORCING. THE LATEST HRRR IS ADVERTISING THE NRN ACTIVITY WILL QUICKLY DIMINISH THE NEXT COUPLE HOURS WHILE SW TSTMS BECOME DOMINATE FEATURE AND EXPAND INTO THE CWA EARLY THIS MORNING. FOR TODAY/TONIGHT...EXPECT COMBINATION OF DAYTIME HEATING AND MOISTURE RICH ENVIRONMENT EXPECT WILL ALLOW FOR QUICK DESTABILIZATION AND TSTM REDEVELOPMENT ALONG AXIS OF BNDRY LYR THETA-E CONVG WITH APPROACH OF FRONTAL BNDRY FROM THE NORTH. AS FOR SEVERE TSTM POTENTIAL...BOTH NAM AND GFS ARE IN PRETTY GOOD AGREEMENT SHOWING HIGH BUOYANCY BUT RELATIVELY WEAK VERTICAL WIND SHEAR THUS FAVORING MULTISTORM DEVELOPMENT. NEVERTHELESS...CANNOT TOTALLY DISCOUNT A FEW SEVERE STORMS LATE AFTN/EARLY EVENING. PCPN ACTIVITY WILL BE COMING TO AN END THEN MONDAY MORNING AS DRY AIRMASS/SUBSIDENCE BUILDS IN FROM THE NORTH. TUES/TUES NIGHT...MODELS LAY QPF WEST OF THE CWA WITHIN AREA OF PRONOUNCED MID LYR AGEOSTROPHIC LIFT. PCPN ACTIVITY THEN PROGGED TO EXPAND QUICKLY EWD INTO THE CWA...THUS WILL LEAVE GOING POPS IN PLACE. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 234 AM CDT SUN JUN 22 2014 GOING FCST HAS PCPN CHANCES PRETTY MUCH IN PLACE THRU THE EXTENDED PDS. AT THIS POINT GIVEN LATEST MODELS SUPPORT GOING POPS...SEE LITTLE REASON FOR MAKING ANY MAJOR MODIFICATIONS. ZONAL FLOW EARLY ON IN THE FCST PD BECOMES MORE AMPLIFIED IN RESPONSE TO A DEEP UPSTREAM UPPER TROF MOVING ONTO THE WEST COAST THURSDAY BEFORE LARGE SCALE BEGINS SMOOTHING OUT TO NEAR ZONAL NEXT WEEKEND. PCPN CHANCE PRETTY MUCH REVOLVING AROUND LIFTING WARM FRONT FOLLOWED BY A COLD FRONT ADVANCING THRU THE CNTRL PLAINS. THERMAL ADVECTION WITH THESE BOUNDARIES LOOKS RELATIVELY WEAK SO NOT MUCH DEVIATION FROM NEAR NORMAL TEMPS ANTICIPATED. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1214 PM CDT SUN JUN 22 2014 ALTHOUGH MORNING CONVECTION HAD SHIFTED SE OF TAF SITES AS OF 17Z...REDEVELOPMENT REMAINS POSSIBLE THROUGH EARLY EVENING AS WEAK BOUNDARY SAGS SE THROUGH AREA. HOWEVER...TIMING AND COVERAGE WAS VERY UNCERTAIN AND THUS NO MENTION WAS MADE IN 18Z TAFS. TRENDS WILL BE MONITORED FOR QUICK UPDATES IF CONDITIONS WARRANT. OTHERWISE WITH RESIDUAL MOISTURE AROUND...HEATING INTO EARLY AFTN COMBINED WITH WEAK OUTFLOW FROM MORNING CONVECTION COULD ALLOW FOR OCCASIONAL MVFR CIGS TO PREVAIL AT SITES. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...CHERMOK SHORT TERM...DEE LONG TERM...DEE AVIATION...CHERMOK
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1049 AM CDT SUN JUN 22 2014 .UPDATE... ISSUED AT 1048 AM CDT SUN JUN 22 2014 THE FORECAST WAS UPDATED FOR PRECIPITATION AND WEATHER FOR TODAY. PARTLY TO MOSTLY SUNNY SKIES ARE CURRENTLY BEING OBSERVED. THE RAIN OVER THE NORTHEAST PART OF THE FORECAST AREA HAS MOVED EAST OF THE AREA. WITH THE EXCEPTION OF A FEW WEAK RADAR ECHOES THAT HAVE MOVED ACROSS NORTHERN SHERIDAN COUNTY...THE SHOWERS AND ISOLATED THUNDERSTORMS OVER SOUTH DAKOTA HAVE STAYED NORTH OF THE FORECAST AREA. THE HRRR HAS BEEN HANDLING THIS ACTIVITY FAIRLY WELL...HAVING IT MOVE STRAIGHT EAST RATHER THAN DIPPING SOUTH AS HAD BEEN PREVIOUSLY FORECAST. DUE TO THES TRENDS...CHANCES HAVE BEEN REMOVED FOR MOST PLACES THROUGH THE MORNING HOURS. THERE IS SOME INSTABILITY ACROSS THE AREA...IN THE ORDER OF 500-1500 J/KG SB CAPE ACCORDING TO THE SPC MESOANALYST PAGE AT 1530Z. THIS SHOULD STAY FAIRLY STABLE THROUGH THE AFTERNOON. THERE WILL BE A LACK OF FORCING THOUGH THIS AFTERNOON AS SHORTWAVES ARE LOOKING TO MOVE ACROSS SOUTH DAKOTA...AND THEN OUT OF COLORADO AND INTO KANSAS LATER IN THE DAY. FEEL THAT THERE MAY BE SOME ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS...BUT WITH THE LACK OF FORCING ACTIVITY SHOULDN/T BE WIDESPREAD SO HAVE LOWERED THE COVERAGE OF STORMS IN THE FORECAST FOR THIS AFTERNOON. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT SUN JUN 22 2014 OUTFLOW DOMINANT TSTMS CONTINUE TO DEVELOP PRODUCING LOCALLY HEAVY RAINFALL THIS MORNING. STORM DEVELOPMENT IS BEING AIDED BY MODEST MOISTURE ADVECTION AS SHOWN BY THE RAP MODEL AND NOCTURNAL COOLING IN THE MID LEVELS OF THE ATMOSPHERE. THE RAP SHOWS THIS MOISTURE TRANSPORT SHIFTING OFF EAST OF THE FCST AREA TOWARD 12Z WITH THE HEAVY RAIN BECOMING LIGHT TO MODERATE. THE ATMOSPHERE IS EXPECTED TO BECOME UNSTABLE THIS AFTERNOON WITH CONVECTION REDEVELOPING BUT NOT NEARLY AS UNSTABLE AS IT IS NOW. SCATTERED POPS ARE IN PLACE FOR THE AFTERNOON HOURS WHICH BECOME ISOLATED TONIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 345 AM CDT SUN JUN 22 2014 MONDAY AND BEYOND. ACTIVE PATTERN TO CONTINUE THROUGH MUCH OF THE EXTENDED AS PLENTIFUL GULF MOISTURE WORKS WITH A NORTHWARD RETREATING FRONTAL BOUNDARY AND PERIODIC WEAK IMPULSES PASSING THROUGH THE WESTERLIES IN QUASI ZONAL FLOW...THUS...NEAR DAILY/NIGHTLY THUNDERSTORMS CHANCES TO REMAIN IN THE EXTENDED FORECAST. LOOKING TO LATE WEEK...THE SYNOPTIC SCALE FLOW ACROSS THE CENTRAL/NORTHERN PLAINS APPEARS TO UNDERGO A TRANSITION AS THERE REMAINS STRONG AGREEMENT OF THE DEVELOPMENT OF A SIGNIFICANT UPPER TROUGH OVER THE WESTERN CONUS. LOW AMPLITUDE TRANSITORY RIDGING THURSDAY MAY PROVIDE FOR A BRIEF DRY PERIOD...BUT PRECIPITATION CHANCES RAMP BACK UP WITH THE APPROACH OF WEAK SHORTWAVES FROM THE WESTERN CONUS TROUGH LATE WEEK AND NEXT WEEKEND. FOR THE DAILY DETAILS...DRIER AIR TO WORK ACROSS WESTERN AND NORTH CENTRAL NEBRASKA ON MONDAY...WITH PLEASANT CONDITIONS ANTICIPATED FOR MOST IF NOT ALL OF THE CWA. THE EXCEPTION BEING WHERE WEAK UPSLOPE FLOW AND THE PASSAGE OF THE NEXT SUBTLE WAVE MAY PROVIDE FOR A FEW STORMS MONDAY EVENING AND THROUGH THE OVERNIGHT ACROSS THE HIGHER TERRAIN OF WESTERN NEBRASKA. WILL MAINTAIN SLIGHT CHANCE POPS IN THIS AREA...BUT EXPECT MOST OF THE ACTIVITY TO BE TIED TO THE HIGHER TERRAIN WEST OF THE CWA. A MORE NOTABLE WAVE ARRIVES ON TUESDAY WHEN THE AFOREMENTIONED FRONT LIFTS NORTH ACROSS THE AREA. WITH RETURN SOUTHERLY FLOW IN PLACE...MOISTURE WILL BE AVAILABLE FOR STORMS...POSSIBLY WIDESPREAD WITH HEAVY RAINFALL. THIS ACTIVITY WILL SPREAD EAST THROUGH THE DAY...WITH ADDITIONAL STORMS POSSIBLE OVERNIGHT WITH THE DEVELOPMENT OF A WEAK TO MODERATE HIGH PLAINS LLJ. TIMING AND LOCATION OF THE PROJECTED CONVECTION AND/OR COMPLEXES IS NOT READILY APPARENT ATTM...SO WILL GENERALLY BROADBRUSH 30-40% POPS MOVING WEST TO EAST ACROSS THE ENTIRE CWA TUESDAY THROUGH EARLY WEDNESDAY MORNING. ADDITIONAL STORMS WILL BE POSSIBLE WEDNESDAY AS THE ATMOSPHERE REMAINS UNSTABLE WITH A FRONT IN THE REGION AND ANOTHER SUBTLE WAVE PASSAGE. LIKEWISE...WIDESPREAD 30-40% POPS WEDNESDAY INTO EARLY THURSDAY ARE WARRANTED. FOR LATE THURSDAY THROUGH THE UPCOMING WEEKEND...MOST OF THE UPPER ENERGY IS SHOWN TO BE DIRECTED TO THE WEST AND NORTH OF THE CWA...BUT THERE STILL REMAINS STRONG SUPPORT OF WAVE IMPACTING THE CWA FRIDAY NIGHT INTO SATURDAY. THE CR ALLBLEND INT GENERATED CHANCE POPS FOR MUCH OF THE CWA...GIVEN THIS SUPPORT...SEE NO REASON TO DEVIATE FROM THE PROCEDURE ATTM. TEMPERATURES THROUGH THE EXTEND PERIODS WILL UNDERGO A SLIGHT WARMING TREND WITH HIGHS GENERALLY IN THE UPPER 70S TO LOWER 80S ON MONDAY...BUT RISE INTO THE MID TO UPPER 80S BY FRIDAY. A FEW LOWER 90S MAY BE POSSIBLE SOUTH OF THE INTERSTATE LATE WEEK AS DEVELOPING SURFACE LOW DIRECTS AN AIRMASS FROM THE DESERT SW INTO WESTERN NEBRASKA. LOWS TO REMAIN SEASONAL THROUGH THE EXTENDED FORECAST PERIODS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 619 AM CDT SUN JUN 22 2014 WITH THE EXCEPTION OF SCATTERED TSTMS...VFR IS EXPECTED MOST AREAS TODAY AND TONIGHT. THE DISTURBANCE OVER NERN WY MOVES THROUGH WRN/NCNTL NEB TODAY AND EXITS THIS EVENING. THE MODEL CONSENSUS SUGGESTS TSTM ACTIVITY WOULD EXPAND IN COVERAGE ACROSS THE SANDHILLS THIS AFTN AND CONTINUE SOUTH AND EAST THROUGH THE FCST AREA BEFORE EXITING THIS EVENING. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...BROOKS SHORT TERM...CDC LONG TERM...JACOBS AVIATION...CDC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
624 AM CDT SUN JUN 22 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 234 AM CDT SUN JUN 22 2014 MOSAIC RADAR IMAGERY THIS MORNING SHOWING TWO DISTINCT CLUSTER OF TSTMS...ONE OVER ERN SD ASSOCIATED WITH A SEWD BOUND COLD FRONT/MID LYR UPGLIDE. OTHER ONE WAS SITUATED ALONG INVERTED SFC TROF/THERMAL BNDRY EXTENDING FROM NW KS INTO S-CNTRL NEB WITHIN AREA OF MID LYR QG FORCING. THE LATEST HRRR IS ADVERTISING THE NRN ACTIVITY WILL QUICKLY DIMINISH THE NEXT COUPLE HOURS WHILE SW TSTMS BECOME DOMINATE FEATURE AND EXPAND INTO THE CWA EARLY THIS MORNING. FOR TODAY/TONIGHT...EXPECT COMBINATION OF DAYTIME HEATING AND MOISTURE RICH ENVIRONMENT EXPECT WILL ALLOW FOR QUICK DESTABILIZATION AND TSTM REDEVELOPMENT ALONG AXIS OF BNDRY LYR THETA-E CONVG WITH APPROACH OF FRONTAL BNDRY FROM THE NORTH. AS FOR SEVERE TSTM POTENTIAL...BOTH NAM AND GFS ARE IN PRETTY GOOD AGREEMENT SHOWING HIGH BUOYANCY BUT RELATIVELY WEAK VERTICAL WIND SHEAR THUS FAVORING MULTISTORM DEVELOPMENT. NEVERTHELESS...CANNOT TOTALLY DISCOUNT A FEW SEVERE STORMS LATE AFTN/EARLY EVENING. PCPN ACTIVITY WILL BE COMING TO AN END THEN MONDAY MORNING AS DRY AIRMASS/SUBSIDENCE BUILDS IN FROM THE NORTH. TUES/TUES NIGHT...MODELS LAY QPF WEST OF THE CWA WITHIN AREA OF PRONOUNCED MID LYR AGEOSTROPHIC LIFT. PCPN ACTIVITY THEN PROGGED TO EXPAND QUICKLY EWD INTO THE CWA...THUS WILL LEAVE GOING POPS IN PLACE. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 234 AM CDT SUN JUN 22 2014 GOING FCST HAS PCPN CHANCES PRETTY MUCH IN PLACE THRU THE EXTENDED PDS. AT THIS POINT GIVEN LATEST MODELS SUPPORT GOING POPS...SEE LITTLE REASON FOR MAKING ANY MAJOR MODIFICATIONS. ZONAL FLOW EARLY ON IN THE FCST PD BECOMES MORE AMPLIFIED IN RESPONSE TO A DEEP UPSTREAM UPPER TROF MOVING ONTO THE WEST COAST THURSDAY BEFORE LARGE SCALE BEGINS SMOOTHING OUT TO NEAR ZONAL NEXT WEEKEND. PCPN CHANCE PRETTY MUCH REVOLVING AROUND LIFTING WARM FRONT FOLLOWED BY A COLD FRONT ADVANCING THRU THE CNTRL PLAINS. THERMAL ADVECTION WITH THESE BOUNDARIES LOOKS RELATIVELY WEAK SO NOT MUCH DEVIATION FROM NEAR NORMAL TEMPS ANTICIPATED. && .AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 620 AM CDT SUN JUN 22 2014 MORNING THUNDERSTORMS HAVE PASSED BY KOFK/KLNK...AND SHOULD PASS BY KOMA IN THE NEXT HOUR OR SO. SHOWERS SHOULD LINGER FOR A COUPLE OF HOURS AFTER THAT...WITH ALL ACTIVITY MOVING OUT BY MID- MORNING. WINDS WILL BE VARIABLE BUT MAINLY 10KT OR LESS FROM MORNING THROUGH AFTERNOON. SHOWERS/STORMS MAY REDEVELOP IN NEB LATER TODAY...BUT CONFIDENCE IS LOW IN DEVELOPMENT AND POTENTIAL PLACEMENT...AND HAVE LEFT MENTION OUT OF TAF SITES. WINDS WILL BECOME NORTHWESTERLY AT ALL SITES BETWEEN 00-06Z AS COLD FRONT SAGS THROUGH TAF SITES...WITH CLEARING BEHIND THE FRONT. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...DEE LONG TERM...DEE AVIATION...MAYES
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
622 AM CDT SUN JUN 22 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT SUN JUN 22 2014 OUTFLOW DOMINANT TSTMS CONTINUE TO DEVELOP PRODUCING LOCALLY HEAVY RAINFALL THIS MORNING. STORM DEVELOPMENT IS BEING AIDED BY MODEST MOISTURE ADVECTION AS SHOWN BY THE RAP MODEL AND NOCTURNAL COOLING IN THE MID LEVELS OF THE ATMOSPHERE. THE RAP SHOWS THIS MOISTURE TRANSPORT SHIFTING OFF EAST OF THE FCST AREA TOWARD 12Z WITH THE HEAVY RAIN BECOMING LIGHT TO MODERATE. THE ATMOSPHERE IS EXPECTED TO BECOME UNSTABLE THIS AFTERNOON WITH CONVECTION REDEVELOPING BUT NOT NEARLY AS UNSTABLE AS IT IS NOW. SCATTERED POPS ARE IN PLACE FOR THE AFTERNOON HOURS WHICH BECOME ISOLATED TONIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 345 AM CDT SUN JUN 22 2014 MONDAY AND BEYOND. ACTIVE PATTERN TO CONTINUE THROUGH MUCH OF THE EXTENDED AS PLENTIFUL GULF MOISTURE WORKS WITH A NORTHWARD RETREATING FRONTAL BOUNDARY AND PERIODIC WEAK IMPULSES PASSING THROUGH THE WESTERLIES IN QUASI ZONAL FLOW...THUS...NEAR DAILY/NIGHTLY THUNDERSTORMS CHANCES TO REMAIN IN THE EXTENDED FORECAST. LOOKING TO LATE WEEK...THE SYNOPTIC SCALE FLOW ACROSS THE CENTRAL/NORTHERN PLAINS APPEARS TO UNDERGO A TRANSITION AS THERE REMAINS STRONG AGREEMENT OF THE DEVELOPMENT OF A SIGNIFICANT UPPER TROUGH OVER THE WESTERN CONUS. LOW AMPLITUDE TRANSITORY RIDGING THURSDAY MAY PROVIDE FOR A BRIEF DRY PERIOD...BUT PRECIPITATION CHANCES RAMP BACK UP WITH THE APPROACH OF WEAK SHORTWAVES FROM THE WESTERN CONUS TROUGH LATE WEEK AND NEXT WEEKEND. FOR THE DAILY DETAILS...DRIER AIR TO WORK ACROSS WESTERN AND NORTH CENTRAL NEBRASKA ON MONDAY...WITH PLEASANT CONDITIONS ANTICIPATED FOR MOST IF NOT ALL OF THE CWA. THE EXCEPTION BEING WHERE WEAK UPSLOPE FLOW AND THE PASSAGE OF THE NEXT SUBTLE WAVE MAY PROVIDE FOR A FEW STORMS MONDAY EVENING AND THROUGH THE OVERNIGHT ACROSS THE HIGHER TERRAIN OF WESTERN NEBRASKA. WILL MAINTAIN SLIGHT CHANCE POPS IN THIS AREA...BUT EXPECT MOST OF THE ACTIVITY TO BE TIED TO THE HIGHER TERRAIN WEST OF THE CWA. A MORE NOTABLE WAVE ARRIVES ON TUESDAY WHEN THE AFOREMENTIONED FRONT LIFTS NORTH ACROSS THE AREA. WITH RETURN SOUTHERLY FLOW IN PLACE...MOISTURE WILL BE AVAILABLE FOR STORMS...POSSIBLY WIDESPREAD WITH HEAVY RAINFALL. THIS ACTIVITY WILL SPREAD EAST THROUGH THE DAY...WITH ADDITIONAL STORMS POSSIBLE OVERNIGHT WITH THE DEVELOPMENT OF A WEAK TO MODERATE HIGH PLAINS LLJ. TIMING AND LOCATION OF THE PROJECTED CONVECTION AND/OR COMPLEXES IS NOT READILY APPARENT ATTM...SO WILL GENERALLY BROADBRUSH 30-40% POPS MOVING WEST TO EAST ACROSS THE ENTIRE CWA TUESDAY THROUGH EARLY WEDNESDAY MORNING. ADDITIONAL STORMS WILL BE POSSIBLE WEDNESDAY AS THE ATMOSPHERE REMAINS UNSTABLE WITH A FRONT IN THE REGION AND ANOTHER SUBTLE WAVE PASSAGE. LIKEWISE...WIDESPREAD 30-40% POPS WEDNESDAY INTO EARLY THURSDAY ARE WARRANTED. FOR LATE THURSDAY THROUGH THE UPCOMING WEEKEND...MOST OF THE UPPER ENERGY IS SHOWN TO BE DIRECTED TO THE WEST AND NORTH OF THE CWA...BUT THERE STILL REMAINS STRONG SUPPORT OF WAVE IMPACTING THE CWA FRIDAY NIGHT INTO SATURDAY. THE CR ALLBLEND INT GENERATED CHANCE POPS FOR MUCH OF THE CWA...GIVEN THIS SUPPORT...SEE NO REASON TO DEVIATE FROM THE PROCEDURE ATTM. TEMPERATURES THROUGH THE EXTEND PERIODS WILL UNDERGO A SLIGHT WARMING TREND WITH HIGHS GENERALLY IN THE UPPER 70S TO LOWER 80S ON MONDAY...BUT RISE INTO THE MID TO UPPER 80S BY FRIDAY. A FEW LOWER 90S MAY BE POSSIBLE SOUTH OF THE INTERSTATE LATE WEEK AS DEVELOPING SURFACE LOW DIRECTS AN AIRMASS FROM THE DESERT SW INTO WESTERN NEBRASKA. LOWS TO REMAIN SEASONAL THROUGH THE EXTENDED FORECAST PERIODS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 619 AM CDT SUN JUN 22 2014 WITH THE EXCEPTION OF SCATTERED TSTMS...VFR IS EXPECTED MOST AREAS TODAY AND TONIGHT. THE DISTURBANCE OVER NERN WY MOVES THROUGH WRN/NCNTL NEB TODAY AND EXITS THIS EVENING. THE MODEL CONSENSUS SUGGESTS TSTM ACTIVITY WOULD EXPAND IN COVERAGE ACROSS THE SANDHILLS THIS AFTN AND CONTINUE SOUTH AND EAST THROUGH THE FCST AREA BEFORE EXITING THIS EVENING. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...JACOBS AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
345 AM CDT SUN JUN 22 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT SUN JUN 22 2014 OUTFLOW DOMINANT TSTMS CONTINUE TO DEVELOP PRODUCING LOCALLY HEAVY RAINFALL THIS MORNING. STORM DEVELOPMENT IS BEING AIDED BY MODEST MOISTURE ADVECTION AS SHOWN BY THE RAP MODEL AND NOCTURNAL COOLING IN THE MID LEVELS OF THE ATMOSPHERE. THE RAP SHOWS THIS MOISTURE TRANSPORT SHIFTING OFF EAST OF THE FCST AREA TOWARD 12Z WITH THE HEAVY RAIN BECOMING LIGHT TO MODERATE. THE ATMOSPHERE IS EXPECTED TO BECOME UNSTABLE THIS AFTERNOON WITH CONVECTION REDEVELOPING BUT NOT NEARLY AS UNSTABLE AS IT IS NOW. SCATTERED POPS ARE IN PLACE FOR THE AFTERNOON HOURS WHICH BECOME ISOLATED TONIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 345 AM CDT SUN JUN 22 2014 MONDAY AND BEYOND. ACTIVE PATTERN TO CONTINUE THROUGH MUCH OF THE EXTENDED AS PLENTIFUL GULF MOISTURE WORKS WITH A NORTHWARD RETREATING FRONTAL BOUNDARY AND PERIODIC WEAK IMPULSES PASSING THROUGH THE WESTERLIES IN QUASI ZONAL FLOW...THUS...NEAR DAILY/NIGHTLY THUNDERSTORMS CHANCES TO REMAIN IN THE EXTENDED FORECAST. LOOKING TO LATE WEEK...THE SYNOPTIC SCALE FLOW ACROSS THE CENTRAL/NORTHERN PLAINS APPEARS TO UNDERGO A TRANSITION AS THERE REMAINS STRONG AGREEMENT OF THE DEVELOPMENT OF A SIGNIFICANT UPPER TROUGH OVER THE WESTERN CONUS. LOW AMPLITUDE TRANSITORY RIDGING THURSDAY MAY PROVIDE FOR A BRIEF DRY PERIOD...BUT PRECIPITATION CHANCES RAMP BACK UP WITH THE APPROACH OF WEAK SHORTWAVES FROM THE WESTERN CONUS TROUGH LATE WEEK AND NEXT WEEKEND. FOR THE DAILY DETAILS...DRIER AIR TO WORK ACROSS WESTERN AND NORTH CENTRAL NEBRASKA ON MONDAY...WITH PLEASANT CONDITIONS ANTICIPATED FOR MOST IF NOT ALL OF THE CWA. THE EXCEPTION BEING WHERE WEAK UPSLOPE FLOW AND THE PASSAGE OF THE NEXT SUBTLE WAVE MAY PROVIDE FOR A FEW STORMS MONDAY EVENING AND THROUGH THE OVERNIGHT ACROSS THE HIGHER TERRAIN OF WESTERN NEBRASKA. WILL MAINTAIN SLIGHT CHANCE POPS IN THIS AREA...BUT EXPECT MOST OF THE ACTIVITY TO BE TIED TO THE HIGHER TERRAIN WEST OF THE CWA. A MORE NOTABLE WAVE ARRIVES ON TUESDAY WHEN THE AFOREMENTIONED FRONT LIFTS NORTH ACROSS THE AREA. WITH RETURN SOUTHERLY FLOW IN PLACE...MOISTURE WILL BE AVAILABLE FOR STORMS...POSSIBLY WIDESPREAD WITH HEAVY RAINFALL. THIS ACTIVITY WILL SPREAD EAST THROUGH THE DAY...WITH ADDITIONAL STORMS POSSIBLE OVERNIGHT WITH THE DEVELOPMENT OF A WEAK TO MODERATE HIGH PLAINS LLJ. TIMING AND LOCATION OF THE PROJECTED CONVECTION AND/OR COMPLEXES IS NOT READILY APPARENT ATTM...SO WILL GENERALLY BROADBRUSH 30-40% POPS MOVING WEST TO EAST ACROSS THE ENTIRE CWA TUESDAY THROUGH EARLY WEDNESDAY MORNING. ADDITIONAL STORMS WILL BE POSSIBLE WEDNESDAY AS THE ATMOSPHERE REMAINS UNSTABLE WITH A FRONT IN THE REGION AND ANOTHER SUBTLE WAVE PASSAGE. LIKEWISE...WIDESPREAD 30-40% POPS WEDNESDAY INTO EARLY THURSDAY ARE WARRANTED. FOR LATE THURSDAY THROUGH THE UPCOMING WEEKEND...MOST OF THE UPPER ENERGY IS SHOWN TO BE DIRECTED TO THE WEST AND NORTH OF THE CWA...BUT THERE STILL REMAINS STRONG SUPPORT OF WAVE IMPACTING THE CWA FRIDAY NIGHT INTO SATURDAY. THE CR ALLBLEND INT GENERATED CHANCE POPS FOR MUCH OF THE CWA...GIVEN THIS SUPPORT...SEE NO REASON TO DEVIATE FROM THE PROCEDURE ATTM. TEMPERATURES THROUGH THE EXTEND PERIODS WILL UNDERGO A SLIGHT WARMING TREND WITH HIGHS GENERALLY IN THE UPPER 70S TO LOWER 80S ON MONDAY...BUT RISE INTO THE MID TO UPPER 80S BY FRIDAY. A FEW LOWER 90S MAY BE POSSIBLE SOUTH OF THE INTERSTATE LATE WEEK AS DEVELOPING SURFACE LOW DIRECTS AN AIRMASS FROM THE DESERT SW INTO WESTERN NEBRASKA. LOWS TO REMAIN SEASONAL THROUGH THE EXTENDED FORECAST PERIODS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1141 PM CDT SAT JUN 21 2014 THUNDERSTORMS ARE POSSIBLE IN THE VICINITY OF THE KLBF AND KVTN TERMINALS THROUGH 09Z SUNDAY. THUNDERSTORMS WILL BE POSSIBLE ONCE AGAIN SUNDAY AFTERNOON AT BOTH THE KLBF AND KVTN TERMINALS. VISBYS MAY DROP AS LOW AS 3SM IN THE VICINITY OF THUNDERSTORMS WITH CIGS AS LOW AS 5000 FT AGL. CIGS AWAY FROM THUNDERSTORMS WILL BE AROUND 10000 FT AGL...EXCEPT SUNDAY EVENING WHERE CIGS WILL DROP TO 2500 TO 5000 FT AGL BEHIND AN EXITING FRONT. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...JACOBS AVIATION...CLB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
239 AM CDT SUN JUN 22 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 234 AM CDT SUN JUN 22 2014 MOSAIC RADAR IMAGERY THIS MORNING SHOWING TWO DISTINCT CLUSTER OF TSTMS...ONE OVER ERN SD ASSOCIATED WITH A SEWD BOUND COLD FRONT/MID LYR UPGLIDE. OTHER ONE WAS SITUATED ALONG INVERTED SFC TROF/THERMAL BNDRY EXTENDING FROM NW KS INTO S-CNTRL NEB WITHIN AREA OF MID LYR QG FORCING. THE LATEST HRRR IS ADVERTISING THE NRN ACTIVITY WILL QUICKLY DIMINISH THE NEXT COUPLE HOURS WHILE SW TSTMS BECOME DOMINATE FEATURE AND EXPAND INTO THE CWA EARLY THIS MORNING. FOR TODAY/TONIGHT...EXPECT COMBINATION OF DAYTIME HEATING AND MOISTURE RICH ENVIRONMENT EXPECT WILL ALLOW FOR QUICK DESTABILIZATION AND TSTM REDEVELOPMENT ALONG AXIS OF BNDRY LYR THETA-E CONVG WITH APPROACH OF FRONTAL BNDRY FROM THE NORTH. AS FOR SEVERE TSTM POTENTIAL...BOTH NAM AND GFS ARE IN PRETTY GOOD AGREEMENT SHOWING HIGH BUOYANCY BUT RELATIVELY WEAK VERTICAL WIND SHEAR THUS FAVORING MULTISTORM DEVELOPMENT. NEVERTHELESS...CANNOT TOTALLY DISCOUNT A FEW SEVERE STORMS LATE AFTN/EARLY EVENING. PCPN ACTIVITY WILL BE COMING TO AN END THEN MONDAY MORNING AS DRY AIRMASS/SUBSIDENCE BUILDS IN FROM THE NORTH. TUES/TUES NIGHT...MODELS LAY QPF WEST OF THE CWA WITHIN AREA OF PRONOUNCED MID LYR AGEOSTROPHIC LIFT. PCPN ACTIVITY THEN PROGGED TO EXPAND QUICKLY EWD INTO THE CWA...THUS WILL LEAVE GOING POPS IN PLACE. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 234 AM CDT SUN JUN 22 2014 GOING FCST HAS PCPN CHANCES PRETTY MUCH IN PLACE THRU THE EXTENDED PDS. AT THIS POINT GIVEN LATEST MODELS SUPPORT GOING POPS...SEE LITTLE REASON FOR MAKING ANY MAJOR MODIFICATIONS. ZONAL FLOW EARLY ON IN THE FCST PD BECOMES MORE AMPLIFIED IN RESPONSE TO A DEEP UPSTREAM UPPER TROF MOVING ONTO THE WEST COAST THURSDAY BEFORE LARGE SCALE BEGINS SMOOTHING OUT TO NEAR ZONAL NEXT WEEKEND. PCPN CHANCE PRETTY MUCH REVOLVING AROUND LIFTING WARM FRONT FOLLOWED BY A COLD FRONT ADVANCING THRU THE CNTRL PLAINS. THERMAL ADVECTION WITH THESE BOUNDARIES LOOKS RELATIVELY WEAK SO NOT MUCH DEVIATION FROM NEAR NORMAL TEMPS ANTICIPATED. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1146 PM CDT SAT JUN 21 2014 VFR CONDITIONS ARE EXPECTED FOR THE MOST PART. SCATTERED SHOWERS AND THUNDERSTORMS MAY DEVELOP ACROSS ALL OF EASTERN NEBRASKA BUT CONFIDENCE IS LOW ON TIMING AND COVERAGE OF THE THUNDERSTORMS. CHANCES WILL CONTINUE INTO SUNDAY AFTERNOON AND EVENING AHEAD OF A COLD FRONT. WINDS WILL TURN TO THE NORTH AT KOFK AROUND 00Z/MON. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...DEE LONG TERM...DEE AVIATION...KERN
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
147 AM EDT SUN JUN 22 2014 .SYNOPSIS... OTHER THAN A FEW CLOUDS...HIGH PRESSURE WILL BRING FAIR WEATHER AND SEASONABLE TEMPERATURES TO THE REGION THROUGH MONDAY. INCREASING WARMTH AND HUMIDITY WILL BRIEFLY RETURN BY THE MIDDLE OF NEXT WEEK ALONG WITH THE CHANCE OF SHOWERS AND A FEW THUNDERTORMS. THEREAFTER...AN EXTENDED STRETCH OF FAIR AND DRY WEATHER RETURNS FOR LATER NEXT WEEK INTO NEXT WEEKEND AS HIGH PRESSURE BUILDS ACROSS THE NORTHEAST. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1252 AM EDT SUNDAY...STILL CONTENDING WITH VARIABLE MID- LEVEL CLOUDINESS ACROSS NORTHERN NEW YORK INTO NORTHERN/CENTRAL VERMONT AT THIS HOUR. 03Z RAP ANALYSES APPEAR TO HAVE THE BEST HANDLE ON THE LAYER OF CLOUDINESS...MANIFESTING AS HIGHER RH IN THE 850-700 MB LAYER. THOUGH THE RAP WANTS TO KEEP THIS MOISTURE AXIS AROUND THROUGH OVERNIGHT CURRENT SATELLITE TRENDS SUGGEST THAT THE CLOUDS WILL BURN OFF SOONER THAN THAT. I`VE HAD TO ADJUST SKY COVER TO KEEP AT LEAST PARTLY CLOUDY SKIES AROUND BUT EVENTUALLY CLEARING OUT BY THE PRE-DAWN HOURS. THINK THAT AREAS OF RIVER VALLEY FOG ARE STILL POSSIBLE BASED ON NARROW T-TD SPREADS...BUT MAY NOT DEVELOP UNTIL MORE CLEARING CAN TAKE PLACE TOWARDS MORNING. ONLY OTHER CHANGE WAS TO ADJUST MINS BY A DEGREE OR TWO. LOWS TO RANGE FROM THE UPPER 30S/LOW 40S NORTHEAST KINGDOM AND ADIRONDACKS TO THE LOW 50S IN THE CHAMPLAIN AND SAINT LAWRENCE VALLEYS. && .SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/... AS OF 308 PM EDT SATURDAY...IDEAL EARLY SUMMER WEATHER CONTINUES SUNDAY INTO MONDAY WITH SURFACE HIGH PRESSURE REMAINING IN CONTROL ALONG WITH BUILDING MID-LEVEL HEIGHTS ABOVE 850 MB. OUTSIDE A FEW PASSING HIGH CLOUDS AND/OR DIURNALLY-DRIVEN FAIR WEATHER CUMULUS...PLENTY OF SUNSHINE EXPECTED ALONG WITH CHANCES OF PRECIPITATION ESSENTIALLY NIL. BLENDED 18-00Z MODEL-AVERAGED 925MB THERMAL PROGS SUGGEST HIGHS SOLIDLY INTO THE 70S TOMORROW...AND UPPER 70S TO LOWER 80S BY MONDAY AS LIGHT SOUTHERLY RETURN FLOW COMMENCES. HUMIDITY VALUES TO REMAIN QUITE MODEST HOWEVER SO DESPITE THE INCREASE IN WARMTH ON MONDAY SENSIBLE CONDITIONS SHOULD STILL RELATIVELY PLEASANT. BY MONDAY NIGHT A GRADUAL INCREASE IN MID AND HIGH CLOUDS ARE EXPECTED AS MOISTURE GRADUALLY INCREASES AHEAD OF A SHORTWAVE TROUGH ADVANCING EASTWARD FROM THE GREAT LAKES AND SOUTHERN CANADA. CAN`T COMPLETELY RULE OUT A STRAY SHOWER OR STORM TOWARD SUNRISE TUESDAY ACROSS OUR SLV COUNTIES IN CLOSER PROXIMITY TO THE LEAD PRE-FRONTAL TROUGH...BUT THE MAJORITY OF THE NIGHT WILL BE PRECIPITATION-FREE. WITH DEEPENING SOUTHERLY FLOW AND WARM THERMAL ADVECTIVE PROCESSES OVERNIGHT LOWS WILL BE CONSIDERABLY MILDER...LIKELY HOLDING IN THE 60S ACROSS THE CHAMPLAIN AND ST LAWRENCE VALLEYS...AND 50S ELSEWHERE. && .LONG TERM /TUESDAY THROUGH SATURDAY/... AS OF 335 PM EDT SATURDAY...LONG TERM FCST CHALLENGE WL BE TIMING OF SFC BOUNDARY AND ASSOCIATED MOISTURE AND CHCS FOR SHOWERS/STORMS ON TUES INTO WEDS. LATEST 12Z GUIDANCE HAS INCREASED THE TIMING OF THIS FEATURE BY 4 TO 8 HRS...RESULTING IN THE HIGHEST POPS OCCURRING LATE TUES AFTN WESTERN CWA AND OVERNIGHT TUES INTO WEDS ACRS THE REST OF THE FA. THE ECMWF CONTS TO BE THE SLOWEST AND WL FOLLOW GIVEN RECENT VERIFICATION. BREEZY SOUTHERLY FLW WL HELP ADVECT INCREASED INSTABILITY AND MOISTURE INTO OUR CWA ON TUESDAY. PWS VALUES REACH BTWN 1.75 AND 2.0"...WHILE SFC DWPTS SURGE INTO THE 60S...CREATING CAPE READINGS BTWN 800 AND 1200 J/KG ON TUES AFTN. ALSO...NOTED ON SOUNDINGS ESPECIALLY ACRS THE SLV NEAR KMSS THE LLVL WIND PROFILES INCREASE BTWN 30 AND 40 KNOTS AT 85H...SUPPORTING SOME FAVORABLE SHEAR PARAMETERS. GIVEN THE MARGINAL INSTABILITY...THINKING A FAST MOVING LINE OF CONVECTION WL BE POSSIBLE WITH BRIEF HEAVY RAINFALL...GUSTY WINDS...AND SMALL HAIL...ESPECIALLY SLV/DACKS ON TUES AFTN/EVENING. THIS ACTIVITY WL PROBABLY DECREASE IN AREAL COVERAGE/INTENSITY AS IT MOVES EAST INTO VT...WHERE INSTABILITY FROM THE LOSS OF SFC HEATING WL BE LIMITED. CRNT HWO HAS MENTION OF SMALL HAIL/GUSTY WINDS WHICH LOOKS REASONABLE GIVEN MARGINAL INSTABILITY ON TUES. WL MENTION HIGHEST LIKELY POPS LATE TUES INTO EARLY WEDS MORNING. OTHERWISE...SFC BOUNDARY CLRS OUR CWA BY 18Z WEDS...WITH BEST MOISTURE AND INSTABILITY LOCATED ACRS THE MID ATLANTIC/SNE REGION. WL MENTION LIKELY POPS WITH SCHC FOR THUNDER ON WEDS MORNING. FOR LATE WEEK INTO NEXT WEEKEND...STILL SOME UNCERTAINTY ON REDEVELOPMENT OF DEEP TROF ACRS THE NE CONUS AND DRY NW FLW ALOFT. LATEST 12Z ECMWF SHOWS POTENT 5H VORT CROSSING OUR CWA LATE THURS NIGHT INTO FRIDAY...BUT MOISTURE IS LIMITED...SO PROBABLY ONLY AN INCREASE IN CLOUDS. BETTER FRNT AND SOME MID LVL MOISTURE CROSSES OUR REGION LATE SAT INTO SUNDAY OF NEXT WEEK...WITH ADDITIONAL CHC FOR SHOWERS. OVERALL...TEMPS START OUT ABOVE NORMAL ON TUES/WEDS AND TREND BACK SLIGHTLY BLW NORMAL BY LATE WEEK...WITH MAINLY DRY CONDITIONS DEVELOPING AFT WEDS. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... THROUGH 12Z MONDAY...VFR CONDITONS EXPECTED FOR THE MAJORITY OF THE PERIOD. ONLY EXCEPTIONS WILL BE SOME PATCHY FOG/BR AT MPV/SLK 08-12Z. OTHERWISE DRY AND SKC-SCT060. WINDS LIGHT AND VARIABLE DURING THE PRE-DAWN HRS...BECOMING NW AROUND 5 KTS AFTER 14Z...AND LIGHT AND VARIABLE AGAIN TONIGHT. OUTLOOK 12Z MONDAY THROUGH THURSDAY...SURFACE HIGH OVER THE GULF OF MAINE WILL MAINTAIN GENERALLY VFR CONDITIONS MONDAY AND MONDAY NIGHT WITH LIGHT S-SW WINDS. INCREASING HEAT AND HUMIDITY WILL BRING A CHANCE FOR THUNDERSTORMS TUESDAY AFTN/EVE...MAINLY AT THE NY TAF SITES. BRIEF PERIODS OF IFR CONDITIONS AND GUSTY WINDS CAN BE EXPECTED WITH ANY TSTMS THAT FORM LATE TUESDAY. SHOWERS AND ISOLD THUNDERSTORMS REMAIN POSSIBLE TUESDAY NIGHT INTO WEDNESDAY AS A WEAK COLD FRONT SHIFTS EWD THROUGH THE REGION...FOLLOWED BY CLEARING/MAINLY VFR WEDNESDAY NIGHT AND THURSDAY BEHIND THE FRONT. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...JMG NEAR TERM...WGH/LOCONTO SHORT TERM...JMG LONG TERM...TABER AVIATION...BANACOS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1252 AM EDT SUN JUN 22 2014 .SYNOPSIS... OTHER THAN A FEW CLOUDS...HIGH PRESSURE WILL BRING FAIR WEATHER AND SEASONABLE TEMPERATURES TO THE REGION THROUGH MONDAY. INCREASING WARMTH AND HUMIDITY WILL BRIEFLY RETURN BY THE MIDDLE OF NEXT WEEK ALONG WITH THE CHANCE OF SHOWERS AND A FEW THUNDERTORMS. THEREAFTER...AN EXTENDED STRETCH OF FAIR AND DRY WEATHER RETURNS FOR LATER NEXT WEEK INTO NEXT WEEKEND AS HIGH PRESSURE BUILDS ACROSS THE NORTHEAST. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1252 AM EDT SUNDAY...STILL CONTENDING WITH VARIABLE MID- LEVEL CLOUDINESS ACROSS NORTHERN NEW YORK INTO NORTHERN/CENTRAL VERMONT AT THIS HOUR. 03Z RAP ANALYSES APPEAR TO HAVE THE BEST HANDLE ON THE LAYER OF CLOUDINESS...MANIFESTING AS HIGHER RH IN THE 850-700 MB LAYER. THOUGH THE RAP WANTS TO KEEP THIS MOISTURE AXIS AROUND THROUGH OVERNIGHT CURRENT SATELLITE TRENDS SUGGEST THAT THE CLOUDS WILL BURN OFF SOONER THAN THAT. I`VE HAD TO ADJUST SKY COVER TO KEEP AT LEAST PARTLY CLOUDY SKIES AROUND BUT EVENTUALLY CLEARING OUT BY THE PRE-DAWN HOURS. THINK THAT AREAS OF RIVER VALLEY FOG ARE STILL POSSIBLE BASED ON NARROW T-TD SPREADS...BUT MAY NOT DEVELOP UNTIL MORE CLEARING CAN TAKE PLACE TOWARDS MORNING. ONLY OTHER CHANGE WAS TO ADJUST MINS BY A DEGREE OR TWO. LOWS TO RANGE FROM THE UPPER 30S/LOW 40S NORTHEAST KINGDOM AND ADIRONDACKS TO THE LOW 50S IN THE CHAMPLAIN AND SAINT LAWRENCE VALLEYS. && .SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/... AS OF 308 PM EDT SATURDAY...IDEAL EARLY SUMMER WEATHER CONTINUES SUNDAY INTO MONDAY WITH SURFACE HIGH PRESSURE REMAINING IN CONTROL ALONG WITH BUILDING MID-LEVEL HEIGHTS ABOVE 850 MB. OUTSIDE A FEW PASSING HIGH CLOUDS AND/OR DIURNALLY-DRIVEN FAIR WEATHER CUMULUS...PLENTY OF SUNSHINE EXPECTED ALONG WITH CHANCES OF PRECIPITATION ESSENTIALLY NIL. BLENDED 18-00Z MODEL-AVERAGED 925MB THERMAL PROGS SUGGEST HIGHS SOLIDLY INTO THE 70S TOMORROW...AND UPPER 70S TO LOWER 80S BY MONDAY AS LIGHT SOUTHERLY RETURN FLOW COMMENCES. HUMIDITY VALUES TO REMAIN QUITE MODEST HOWEVER SO DESPITE THE INCREASE IN WARMTH ON MONDAY SENSIBLE CONDITIONS SHOULD STILL RELATIVELY PLEASANT. BY MONDAY NIGHT A GRADUAL INCREASE IN MID AND HIGH CLOUDS ARE EXPECTED AS MOISTURE GRADUALLY INCREASES AHEAD OF A SHORTWAVE TROUGH ADVANCING EASTWARD FROM THE GREAT LAKES AND SOUTHERN CANADA. CAN`T COMPLETELY RULE OUT A STRAY SHOWER OR STORM TOWARD SUNRISE TUESDAY ACROSS OUR SLV COUNTIES IN CLOSER PROXIMITY TO THE LEAD PRE-FRONTAL TROUGH...BUT THE MAJORITY OF THE NIGHT WILL BE PRECIPITATION-FREE. WITH DEEPENING SOUTHERLY FLOW AND WARM THERMAL ADVECTIVE PROCESSES OVERNIGHT LOWS WILL BE CONSIDERABLY MILDER...LIKELY HOLDING IN THE 60S ACROSS THE CHAMPLAIN AND ST LAWRENCE VALLEYS...AND 50S ELSEWHERE. && .LONG TERM /TUESDAY THROUGH SATURDAY/... AS OF 335 PM EDT SATURDAY...LONG TERM FCST CHALLENGE WL BE TIMING OF SFC BOUNDARY AND ASSOCIATED MOISTURE AND CHCS FOR SHOWERS/STORMS ON TUES INTO WEDS. LATEST 12Z GUIDANCE HAS INCREASED THE TIMING OF THIS FEATURE BY 4 TO 8 HRS...RESULTING IN THE HIGHEST POPS OCCURRING LATE TUES AFTN WESTERN CWA AND OVERNIGHT TUES INTO WEDS ACRS THE REST OF THE FA. THE ECMWF CONTS TO BE THE SLOWEST AND WL FOLLOW GIVEN RECENT VERIFICATION. BREEZY SOUTHERLY FLW WL HELP ADVECT INCREASED INSTABILITY AND MOISTURE INTO OUR CWA ON TUESDAY. PWS VALUES REACH BTWN 1.75 AND 2.0"...WHILE SFC DWPTS SURGE INTO THE 60S...CREATING CAPE READINGS BTWN 800 AND 1200 J/KG ON TUES AFTN. ALSO...NOTED ON SOUNDINGS ESPECIALLY ACRS THE SLV NEAR KMSS THE LLVL WIND PROFILES INCREASE BTWN 30 AND 40 KNOTS AT 85H...SUPPORTING SOME FAVORABLE SHEAR PARAMETERS. GIVEN THE MARGINAL INSTABILITY...THINKING A FAST MOVING LINE OF CONVECTION WL BE POSSIBLE WITH BRIEF HEAVY RAINFALL...GUSTY WINDS...AND SMALL HAIL...ESPECIALLY SLV/DACKS ON TUES AFTN/EVENING. THIS ACTIVITY WL PROBABLY DECREASE IN AREAL COVERAGE/INTENSITY AS IT MOVES EAST INTO VT...WHERE INSTABILITY FROM THE LOSS OF SFC HEATING WL BE LIMITED. CRNT HWO HAS MENTION OF SMALL HAIL/GUSTY WINDS WHICH LOOKS REASONABLE GIVEN MARGINAL INSTABILITY ON TUES. WL MENTION HIGHEST LIKELY POPS LATE TUES INTO EARLY WEDS MORNING. OTHERWISE...SFC BOUNDARY CLRS OUR CWA BY 18Z WEDS...WITH BEST MOISTURE AND INSTABILITY LOCATED ACRS THE MID ATLANTIC/SNE REGION. WL MENTION LIKELY POPS WITH SCHC FOR THUNDER ON WEDS MORNING. FOR LATE WEEK INTO NEXT WEEKEND...STILL SOME UNCERTAINTY ON REDEVELOPMENT OF DEEP TROF ACRS THE NE CONUS AND DRY NW FLW ALOFT. LATEST 12Z ECMWF SHOWS POTENT 5H VORT CROSSING OUR CWA LATE THURS NIGHT INTO FRIDAY...BUT MOISTURE IS LIMITED...SO PROBABLY ONLY AN INCREASE IN CLOUDS. BETTER FRNT AND SOME MID LVL MOISTURE CROSSES OUR REGION LATE SAT INTO SUNDAY OF NEXT WEEK...WITH ADDITIONAL CHC FOR SHOWERS. OVERALL...TEMPS START OUT ABOVE NORMAL ON TUES/WEDS AND TREND BACK SLIGHTLY BLW NORMAL BY LATE WEEK...WITH MAINLY DRY CONDITIONS DEVELOPING AFT WEDS. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... THROUGH 00Z MONDAY...VFR CONDITONS EXPECTED FOR THE MAJORITY OF THE PERIOD. ONLY EXCEPTIONS WILL BE SOME PATCHY FOG/BR AT MSS/MPV/SLK. SCATTERED CUMULUS CLOUDS FROM THIS AFTERNOON WILL GRADUALLY DISSIPATE THIS EVENING WITH ONLY A FEW LINGERING OVERNIGHT. THIS WILL LEAD TO MOSTLY CLEAR SKIES...WHICH COMBINED WITH LIGHT WINDS AND STRONG RADIATIONAL COOLING...MAY LEAD TO THE DEVELOPMENT OF SOME PATCHY FOG/BR. OVERALL CONDITIONS ARE SIMILAR TO PREVIOUS NIGHT`S...SO TIMING OF FOG DEVELOPMENT SHOULD PLAY OUT SIMILAR AS WELL. SOME MINOR DIFFERENCES NOTED ARE THE SLIGHTLY HIGHER CROSS-OVER TEMPERATURES AT SLK/MSS AND SLIGHTLY WARMER FORECAST LOWS AT MPV. THIS SHOULD LEAD TO SLK HAVING A SOMEWHAT GREATER THREAT FOR IFR OR LOWER FOG. BEST CHANCES FOR FOG RUN 07Z-12Z. AFTERWARD...ADDITIONAL CUMULUS CLOUDS DEVELOP ON SUNDAY BUT ALL SITES WILL BE VFR. CAN`T RULE OUT A VERY LIGHT INSTABILITY RAIN SHOWER AT SLK/MPV BUT WOULD BE VERY ISOLATED. WINDS LIGHT AND LOCALLY VARIABLE TONIGHT REMAIN LIGHT AROUND 5 KNOTS ON SUNDAY...GENERALLY OUT OF THE NORTH/NORTHEAST...EXCEPT EAST AT PBG. OUTLOOK 00Z MONDAY THROUGH THURSDAY...SFC HIGH PRES WL RESULT IN VFR CONDITIONS CONTINUING FROM SUNDAY EVENING THRU 18Z TUES. THE COMBINATION OF INCREASED INSTABILITY AND APPROACHING SFC BOUNDARY WL HELP IN THE DEVELOPMENT OF SCATTERED SHOWERS/STORMS ON TUES AFTN/EVENING. BRIEF PERIODS OF MVFR CIGS/VIS WL BE POSSIBLE...ALONG WITH SOME GUSTY WINDS NEAR THUNDERSTORMS...WHICH WL CREATE AREAS OF LOCALIZED TURBULANCE. ALSO...CHANNEL SOME WIND GUSTS TO 30 MPH WL BE POSSIBLE ON TUES AFTN AT MSS/BTV/PBG...ASSOCIATED WITH A DEVELOPING LLVL JET. VFR CONDITIONS RETURN FOR WEDNESDAY AND THURSDAY. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...JMG NEAR TERM...WGH/LOCONTO SHORT TERM...JMG LONG TERM...TABER AVIATION...TABER/MUCCILLI
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1028 PM EDT MON JUN 23 2014 .SYNOPSIS...HIGH PRESSURE ALONG THE EAST COAST TODAY WILL RETREAT OFFSHORE TONIGHT AND EARLY TUESDAY...THEN BE FOLLOWED BY A WEAK LEE SURFACE TROUGH THROUGH MID-WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1020 PM MONDAY... CONVECTION IS STILL DEVELOPING ALONG THE NORTH-NORTHWESTWARD ADVANCING SEABREEZE THIS EVENING... OVER OUR FAR SOUTHERN SANDHILLS. HOWEVER... IT IS BEGINNING TO WANE IN COVERAGE ACROSS OUR FAR SOUTH/SOUTHWESTERN REACHES THIS EVENING.... WHICH MATCHES UP WELL WITH THE WEAKENING INSTABILITY ACROSS CENTRAL NC. THE BEST LINGERING INSTABILITY REMAINS TO OUR WEST AND SOUTH.... WHERE CONVECTION IS EXPECTED TO LINGER THE LONGEST... LATE EVENING/VERY EARLY TUESDAY MORNING. HOWEVER... LOW LEVEL MOISTURE IS EXPECTED TO INCREASE ACROSS THE AREA THIS EVENING AND OVERNIGHT AS HIGH PRESSURE BEGINS TO RETREAT OFF TO THE NORTHEAST. THIS WILL YIELD A DEVELOPING LOW LEVEL SOUTHERLY TO SOUTHEASTERLY FLOW... WITH THE POTENTIAL FOR STRATUS DEVELOPING ACROSS WESTERN PORTIONS OF CENTRAL NC FIRST THEN SPREADING EASTWARD. LOCATIONS ACROSS THE FAR NORTHEAST (NORTHERN COASTAL PLAIN AND FAR NORTHEAST PIEDMONT) MAY SEE MOSTLY CLEAR SKIES OVERNIGHT THOUGH. MEANWHILE... THE MID LEVEL S/W RIDGE AXIS WILL SLOWLY BEGIN TO SHIFT EASTWARD TONIGHT... POSSIBLY ALLOWING A WEAK DISTURBANCE TO LIFT NORTH-NORTHEASTWARD AND INTO/ACROSS THE WESTERN PIEDMONT. THE LATEST RAP AND HRRR IS SHOWING THIS FEATURE... COUPLED WITH INCREASING LOW LEVEL SOUTHERLY/SOUTHEASTERLY FLOW... HELPING TO DEVELOP SOME CONVECTION OVERNIGHT ACROSS OUR FAR WESTERN PIEDMONT. GIVEN THE TIME OF NIGHT WITH THE RAP SHOWING FURTHER STABILIZATION ACROSS OUR AREA AND TO THE WEST... CONFIDENCE REMAINS LOW OF SEEING MUCH IN THE WAY OF ANY SHOWERS AFTER MIDNIGHT (WHEN THE RAP AND HRRR SHOW SHOWERS DEVELOPING). THUS... WILL JUST ADDED A SLIGHT CHANCE OF SHOWERS TO OUR WESTERN PIEDMONT AT THIS TIME IN THE 04-11Z TIME FRAME. LOWS TUESDAY MORNING ARE EXPECTED TO RANGE NEAR THE MID 60S NORTHEAST TO NEAR 70 FAR SOUTHWEST/SOUTH. && .SHORT TERM /TUESDAY AND TUESDAY NIGHT/... AS OF 300 PM MONDAY... A LOW AMPLITUDE SHORTWAVE TROUGH AND IT`S WEAK SURFACE FRONT REFLECTION WILL PROGRESS EAST-NORTHEASTWARD FROM THE MS VALLEY AND INTO THE OHIO VALLEY TUESDAY NIGHT. WHILE THIS FEATURE WILL REMAIN WEST AND NORTH OF THE AREA...WEAK SHORTWAVE IMPULSES EJECTING EAST- NORTHEASTWARD OUT AHEAD OF THE TROUGH COULD POSSIBLY PROVIDE SOME WEAK SUPPORT ALOFT IN CONCERT WITH INCREASINGLY BOUNDARY LAYER MOISTURE/BUOYANCY AS SOUTHERLY RETURN OVERSPREADS THE AREA WITH THE DEVELOPMENT OF A LEE TROUGH TUESDAY EVENING/NIGHT. HIGHEST POPS SHOULD EXTEND ACROSS THE SOUTHERN AND WESTERN ZONES...LOWEST IN THE NORTHEAST. GIVEN WEAK FORCING AND SHEAR AND ONLY MODEST DESTABILIZATION OF 1000-1500 J/KG...SEVERE THREAT WILL BE TOO LOW/ISOLATED TO WARRANT A MENTION IN THE HWO. HIGHS IN THE MID 80S NORTH TO LOWER 90S SOUTH. LOWS 68 TO 72. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... AS OF 300 PM MONDAY... THE BEST TIME FRAME FOR PRECIP IN THE LONG TERM PERIOD LOOKS TO BE WEDNESDAY/WEDNESDAY NIGHT AS A SHORTWAVE TROUGH PROGRESSES EAST OVER THE REGION...PUSHING A SURFACE FRONT TOWARDS THE AREA. THE BEST FORCING WILL REMAIN NORTH OF THE AREA...BUT GIVEN THE BETTER (ALBEIT WEAK) SUPPORT ALOFT AND CONVERGENCE AT THE SURFACE...SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED DURING THE DAY...LIKELY PERSISTING INTO THE OVERNIGHT HOURS. GIVEN WEAK DEEP LAYER SHEAR...AS WELL AS WEAK MID LEVEL LAPSE RATES...SEVERE POTENTIAL WILL BE RATHER LIMITED DESPITE THE MODERATE TO STRONG INSTABILITY THAT IS EXPECTED TO BE OVER THE AREA. FOR THE REMAINDER OF THE LONG TERM PERIOD...THERE IS QUITE A BIT OF SPREAD AMONG THE MODELS... LEADING TO DECREASED CONFIDENCE. OVERALL...RIDGING ALOFT (ALTHOUGH RATHER FLAT) IS PROGGED TO BUILD BACK OVER THE AREA DURING THE LATTER HALF OF THE WEEK...ALLOWING SOME MID LEVEL DRYING TO OCCUR. NEVERTHELESS...MODERATE TO STRONG INSTABILITY WILL RESULT IN CONTINUED PRECIP CHANCES...ALTHOUGH COVERAGE MAY BE SLIGHTLY LESS. DETAILS IN THE MID/UPPER PATTERN BECOMES EVEN MORE UNCLEAR FOR THE WEEKEND AND EARLY NEXT WEEK...BUT NEVERTHELESS PRECIP CHANCES WILL LIKELY PERSIST THROUGH EARLY NEXT WEEK GIVEN THE TYPICAL SUMMERTIME AIRMASS. HIGH TEMPS WILL GENERALLY IN THE UPPER 80S TO LOWER 90S TO START THE PERIOD WITH LOW TO MID 90S EXPECTED BY THE END OF THE WEEK. OVERNIGHT LOWS WILL MOSTLY BE IN THE UPPER 60S TO LOWER 70S. && .AVIATION /00Z MONDAY THROUGH SATURDAY/... AS OF 800 PM MONDAY... THERE AREA FEW SHOWERS ALONG THE SEABREEZE JUST SOUTH OF KFAY...AND LIGHT WINDS MAY BRIEFLY SHIFT FROM EASTERLY TO SOUTHEASTERLY AT KFAY IF THE SEABREEZE MAKES IN THE IN THE NEXT COUPLE OF HOURS. OTHERWISE..VFR CONDITIONS WILL CONTINUE THROUGH 06-09Z...THEN STRATUS MAY BEGIN TO DEVELOP WITH AN INCREASINGLY MOIST SOUTH-SOUTHEASTERLY FLOW. CONFIDENCE IN MVFR STRATUS...POSSIBLY AS LOW AS IFR... IS HIGHEST AT KGSO AND KINT AFTER 09Z. STRATUS MAY ALSO DEVELOP AT...THOUGH CONFIDENCE IS LOWER THERE. STRATUS WILL LIFT TUESDAY MORNING AND LEAD TO VFR CONDITIONS DURING THE DAY. AN ISOLATED SHOWER OR STORMS ILL BE POSSIBLE...MAINLY AT KGSO/KINT/KFAY. OUTLOOK...THE COVERAGE OF SHOWERS AND STORMS WILL INCREASE THROUGH THE REMAINDER OF THE WEEK...WITH THE BEST CHANCE ON WEDNESDAY INTO EARLY THURSDAY. IN ADDITION...EARLY MORNING STRATUS/FOG WILL ALSO BE POSSIBLE. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...MWS NEAR TERM...BSD SHORT TERM...CBL LONG TERM...KRD AVIATION...BLS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
321 PM EDT SUN JUN 22 2014 .SYNOPSIS... WEAK HIGH PRESSURE WILL CONTINUE TO EXTEND SOUTH INTO THE CAROLINAS OVER THE NEXT COUPLE OF DAYS...THOUGH A RISK OF SHOWERS AND THUNDERSTORMS WILL PERSIST THROUGH MID WEEK. BERMUDA HIGH PRESSURE BUILDS BACK IN BY MID WEEK AND WILL CONTINUE TO MAINTAIN ITS INFLUENCE ACROSS THE AREA INTO NEXT WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM SUNDAY...BEST INSTABILITY THRU EARLY THIS EVENING TO RESIDE ACROSS THE ILM SC CWA...MAINLY ALONG AND SOUTH OF HIWAY 378. THE HIGHER POPS OR THE BETTER CHANCE FOR CONVECTION...WILL ALSO BE EXHIBITED HERE. WITH MID-LEVEL DRYING OVERSPREADING THE FA IN THE WAKE OF THE FRONT ESPECIALLY ACROSS THE ILM NC COUNTIES...CONVECTION WILL HAVE A MORE DIFFICULT TIME TO DEVELOP/OCCUR AND THUS A LOWER AFTN/EVNG POP...COMPARED TO ELSEWHERE ACROSS THE FA...WILL BE ILLUSTRATED. MID-LEVEL S/W RIDGING TO AFFECT THE FA...WITH THE UPPER RIDGE AXIS APPROACHING THE FA FROM THE WEST BY DAYBREAK MON. MODELS INDICATE THE ATM TO FURTHER DRY ACROSS THE FA AND THUS WILL BACK OFF WITH THE CLOUDINESS OVERNIGHT. COULD OBSERVE SOME OVERALL CLEAR SKIES OVERNIGHT ESPECIALLY ACROSS THE ILM NC COUNTIES. VARIOUS MODEL TIME HEIGHT DISPLAYS INDICATE THIS ATM DRYING TREND. MODELS ALSO INDICATE A TEMPORARY TIGHTENING OF THE SFC PG AS HIGH PRESSURE BUILDS ACROSS THE BI-STATE REGION IN THE WAKE OF THE COLD FRONT...IN TURN KEEPING A NE-E SFC WIND ACTIVE OVERNIGHT ESPECIALLY AT THE IMMEDIATE COAST. AS FOR TONITES LOWS...HAVE GONE BELOW THE CONSENSUS OF THE VARIOUS MODEL MOS GUIDANCE...WITH MID TO UPPER 60S INLAND...TO AROUND 70 OR LOWER 70S AT THE COAST. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 PM SUNDAY...WITH A WEAK FRONT STALLED SOUTH OF THE AREA...HIGH PRESSURE WILL CONTINUE TO REIGN OVER THE AREA MONDAY MORNING...BEFORE RETREATING BACK TO THE NORTH AS THE SYSTEM PROPAGATES EASTWARD OFF THE NEW ENGLAND COAST LATER IN THE DAY. WITH A SHIFT IN THE PATTERN...SFC WINDS WILL BECOME EASTERLY...AND THEN VEER MORE TO THE EAST-SOUTHEAST INTO MONDAY EVENING. COULD SEE SOME ISOLATED CONVECTION ESPECIALLY IN THE WESTERN SC COUNTIES WITH DAYTIME HEATING GIVEN HIGHER AMOUNTS OF AVAILABLE MOISTURE WITH PWAT VALUES NEAR 1.8 INCHES. AS YOU MOVE EASTWARD TO PWAT VALUES DECREASE TO 1.4/1.5 WHICH CONTINUES TO RUN WELL BELOW CLIMATOLOGY FOR THIS TIME OF YEAR PER LATEST TIME-HEIGHT ANALYSIS AND FCST SOUNDINGS...THUS HAVE KEPT TREND IN LATEST SET OF POPS FOR THIS WITH HIGHEST IN THE WESTERN ZONES. LATEST GUIDANCE LOOKS TO DEPICT A REVERSE TRACK TO THE NORTH OF THE STALLED FRONT TO OUR SOUTH...AND MOISTURE RETURNS TO THE ENTIRE FORECAST AREA WITH PWAT VALUES OF 1.6-2.0 INCHES. THOUGH THE ANTICIPATED FRONT/REMNANTS COULD OFFER SOME LIFT ON TUESDAY...WILL ALSO NEED TO FOCUS ON AFTERNOON SEA BREEZE AND PIEDMONT TROUGH FOR CONVECTION DEVELOPMENT. MODELS DO NOTE SOME WEAK MID-LEVEL CAPPING WHICH COULD INHIBIT DEVELOPMENT...BUT IT IS SHORT-LIVED AND SHOULD NOT INTERFERE WITH DEVELOPMENT BY TUESDAY AFTERNOON. THUS HAVE SLIGHTLY INCREASED POPS...BUT OVERALL GENERAL THINKING REMAINS WITH ISOLATED TO SCATTERED CONVECTION TUESDAY AFTERNOON/EVENING. INTO THE END OF THE PERIOD ACTIVITY WILL TAPER OFF WITH THE LOSS OF DAYTIME HEATING. EXPECT HIGHS ON MONDAY AND TUESDAY TO BE IN THE MID 80S ALONG THE COAST...INCREASING TO THE UPPER 80S INLAND AND LOWER 90S IN THE WESTERN SC COUNTIES. OVERNIGHT LOWS WILL BE IN THE LOWER 70S MONDAY INTO TUESDAY...WITH A FEW DEGREES HIGHER OVERNIGHT TUESDAY AS A MORE WARM AND MOIST AIRMASS RETURNS. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 300 PM SUNDAY...HOT BUT UNSETTLED FOR THE LAST HALF OF THE WEEK AS BERMUDA TYPE HIGH PRESSURE AND SUBTLE TROUGHING ALOFT COMBINE IN A RICH THETA-E ENVIRONMENT. THIS SUPPORTS TEMPS SEVERAL DEGREES ABOVE CLIMO...WIDESPREAD 90S FOR HIGHS...LOW 70S FOR LOWS...WITH HIGH CHC POP FOR DIURNAL TSTMS EACH DAY. TSTMS WILL LIKELY BE MORE WIDESPREAD THAN JUST TYPICAL SUMMERTIME ACTIVITY THANKS TO WEAK IMPULSES MOVING ALOFT...FURTHER ENHANCING PIEDMONT TROUGH AND SEA BREEZE CONVECTION. IT IS INTERESTING TO NOTE THAT GUIDANCE HAS BACKED OFF A BIT ON CONVECTION THU/FRI THANKS TO MID-LEVEL DRYING...BUT THIS IS A NEW SOLUTION...AND WITH THE PATTERN RELATIVELY UNCHANGED WED-FRI...WILL CONTINUE WITH INHERITED HIGH CHC EACH DAY. BY THE WKND...RIDGING BLOSSOMS ACROSS THE SOUTHEAST...BUT A WEAK COLD FRONT WILL TRY TO CROSS THE AREA ON SUNDAY. WILL MAINTAIN SLIGHTLY LOWERED POP THANKS TO SUBSIDENCE BENEATH THE RIDGE...WITH TEMPS REMAINING MOSTLY UNCHANGED. THE EXCEPTION MAY BE SUNDAY IF FROPA OCCURS...BUT FOR NOW WILL EXPECT THE FRONT TO GET HUNG UP TO THE NORTH AND KEEP TEMPS ABOVE NORMAL THROUGH THE PERIOD. && .AVIATION /19Z SUNDAY THROUGH FRIDAY/... AS OF 18Z...THE HRRR MODEL HAS BEEN PRETTY CONSISTENT IN BRINGING DOWN CONVECTION FROM THE MOREHEAD CITY REGION ACROSS THE BI-STATE REGION THIS AFTN. LATEST 88D TRENDS INDICATE CONVECTION HAS INCHED CLOSER BUT REMAINS ISOLATED IN COVERAGE. AT THIS PACE...THE ILM TERMINAL MAY EXPERIENCE A CLAP OF THUNDER WITH AN OUTSIDE SHOT FOR THE MYRTLES TO EXPERIENCE CONVECTION PRIOR TO THE DAYS INSOLATION COMING TO AN END. LOOK FOR POSSIBLE MVFR VISIBILITIES IN THE TSHOWERS. FOR TONIGHT...VFR WITH A PARTLY CLOUDY SKY WITH THE EXCEPTION OF POSSIBLE MVFR CONDITIONS FROM REDUCED VSBY FROM FOG AFTER MIDNIGHT. FOR MONDAY...BECOMING VFR WITH ISOLATED POPS BY LATE MORNING. EXTENDED OUTLOOK...VFR MONDAY. AFTERNOON AND EVENING SHOWERS EXPECTED TUESDAY THROUGH FRIDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM SUNDAY...BROAD SFC LOW PARTIALLY ENCOMPASSING THE ILM COASTAL WATERS...IS PROGGED TO PUSH FURTHER OFFSHORE THIS AFTERNOON WHILE THE FRONTAL BOUNDARY SINKS FURTHER SOUTHWARD IN ITS WAKE. WILL CONTINUE THE WINDS TRANSITIONING FROM A WNW-NNW TO NNE-ENE AS THE SFC RIDGING FROM THE NORTHEAST WORKS ITS WAY ACROSS THE CAROLINAS THIS AFTN AND TONIGHT. WIND SPEEDS AROUND 10 KT...BUT COULD SEE A SOLID 15 KT TONIGHT ACROSS THE ILM NC WATERS FROM THE BRIEF SFC PG TIGHTENING AND ASSOCIATED WEAK POST FRONTAL SURGE. SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...WITH A FEW 4 FOOTERS POSSIBLE ACROSS THE ILM NC WATERS FROM CAPE FEAR NORTHWARD LATE TONIGHT. WIND DRIVEN WAVES EXHIBITING 4 TO 6 SECOND PERIODS TO DOMINATE THE SIGNIFICANT SEAS. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 PM SUNDAY...AN OFFSHORE PROGRESSING HIGH PRESSURE SYSTEM OFF THE NEW ENGLAND COAST WILL ALLOW FOR NORTHEAST TO EAST WINDS EARLY ON MONDAY 10 TO 12 KTS TO VEER AND BECOME EAST-SOUTHEASTERLY INTO THE EVENING HOURS...DROPPING TO A SOLID 10 KTS AND SLIGHTLY LOWER TOWARDS THE COAST. ON TUESDAY...EAST-SOUTHEAST WINDS BECOME SOUTHWEST BY EVENING AS BERMUDA HIGH PRESSURE BUILDS IN...WITH WINDS 10 TO 15 KTS. AS FOR SEAS...EXPECT 1 TO 3 FT THROUGHOUT THE PERIOD. LONG TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 300 PM SUNDAY...LARGE HIGH PRESSURE WELL OFFSHORE WILL MAINTAIN ITS INFLUENCE THROUGH THE EXTENDED...PRODUCING UNIFORM WIND/WAVE CONDITIONS EACH DAY. AS THIS HIGH SITS OFFSHORE...RETURN FLOW WILL ENVELOP THE WATERS...WITH SW WINDS OF 10-15 KTS COMMON THROUGH THE PERIOD. ALTHOUGH A GROUND SWELL WILL SLOWLY AMPLIFY THROUGH LATE WEEK...THE WAVE SPECTRUM WILL BE DOMINATED BY 5-SEC SW WIND WAVES...CREATING 2-4 FT SEAS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...DCH SHORT TERM...SGL LONG TERM...JDW AVIATION...DCH/DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
125 PM EDT SUN JUN 22 2014 .SYNOPSIS... LOW PRESSURE WILL PUSH A FRONT INTO THE REGION THIS MORNING. THIS FRONT WILL STRUGGLE TO MOVE FURTHER SOUTH DURING THE DAY TODAY. WEAK HIGH PRESSURE WILL EXTEND SOUTH INTO THE CAROLINAS...BUT THE RISK OF SHOWERS AND THUNDERSTORMS WILL CONTINUE EACH DAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1110 AM SUNDAY...LATEST SATELLITE IMAGERY AND SFC OBS INDICATE CU/SC DECK OF CLOUDS HAVE DEVELOPED AND/OR OVERSPREAD THE AREA. HAVE CONTINUED THE 20-30 MAINLY RESULTANT WIND/SEA BREEZE TYPE POPS THRU EARLY EVENING. THE BEST INSTABILITY WILL LIE CLOSER TO THE FRONT WITH THE SEA BREEZE/FRONTAL BOUNDARY INTERACTION PROVIDING LIFT. THE ILM SC COUNTIES WILL BE HIGHLIGHTED WITH THE SLIGHTLY BETTER CHANCE FOR CONVECTION. NO CHANGES TO THE MAX TEMPS...WITH MAINLY 80S ACROSS THE ILM NC CWA...WITH 90S ACROSS THE ILM SC CWA. PREVIOUS DISCUSSION................................. AS OF 3 AM SUNDAY...WEAK COLD FRONT WILL DROP THOUGH THE AREA TODAY AND COULD RESULT IN ISOLATED TO SCATTERED SHOWERS AND STORMS...ESPECIALLY NEARER THE COAST DUE TO THE SEA BREEZE AND OVER SOUTHERN AREAS WHERE INSTABILITY WILL BE THE GREATEST. HIGHS TODAY WILL RANGE FROM THE UPPER 80S TO LOWER 90S WITH THE HIGHEST NUMBERS EXPECTED SOUTH AND WEST. MINS TONIGHT WILL FALL TO THE LOWER 70S EXCEPT A FEW UPPER 60S ALONG THE NORTHERN TIER. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 3 AM SUNDAY...HIGH PRESSURE BUILDS DOWN THE COAST EARLY MON AS WEAK FRONT REMAINS STALLED WELL SOUTH OF THE AREA. THE HIGH WILL SHIFT EAST OF NEW ENGLAND CURING THE DAY WITH LOW LEVEL NORTHEAST FLOW IN THE MORNING BECOMING EASTERLY BY AFTERNOON. AT THE SAME TIME THE MID LEVEL PATTERN WILL BE TRANSITIONING TO BRIEF WEAK RIDGING. HEIGHT RISES DURING THE DAY COMBINED WITH NORTHEAST TO EAST LOW LEVEL FLOW WILL WORK TO LIMIT CONVECTION. THERE WILL BE DEEP MOISTURE IN PLACE WITH PRECIPITABLE WATER VALUES IN THE 1.6 TO 1.8 INCH RANGE...ABOVE NORMAL FOR LATE JUNE. DIURNAL HEATING WILL BE ABLE TO GENERATE SOME ISOLATED DEEPER CONVECTION...ESPECIALLY INLAND SC. WILL CONTINUE TO CARRY INHERITED SLIGHT CHC POP EVERYWHERE EXCEPT FOR CHC POP ACROSS INLAND SC WHERE TEMPS WILL BE WARMEST AND LOW LEVEL CONVERGENCE IS STRONGEST. HIGHS WILL END UP A LITTLE BELOW CLIMO MON WHILE LOWS WILL CONTINUE TO RUN NEAR TO SLIGHTLY ABOVE CLIMO. WEAK SHORT DURATION MID LEVEL RIDGE BUILDS OVER THE SOUTHEAST FOR TUE. ALTHOUGH THIS FEATURE WILL OFFER SOME RESISTANCE TO UPWARD MOTION THE SEA BREEZE AND WEAK PIEDMONT TROUGH WILL BE ABLE TO GENERATE SOME DEEP CONVECTION. PRECIPITABLE WATER VALUES REMAIN HIGH...OVER 2 INCHES FORECAST FOR MUCH OF THE AREA...AND LOW LEVEL WARM ADVECTION WILL PUMP PLENTY OF WARM MOIST AIR INTO THE REGION. THERE WILL ALSO BE A WEAK SHORTWAVE MOVING NORTHEAST FROM THE GULF OF MEXICO TUE AFTERNOON. CURRENT TIMING HAS BEST PVA COINCIDENT WITH PEAK HEATING. THUS PLAN TO MAINTAIN INHERITED CHC POP FOR MUCH OF THE AREA. HIGHS WILL BE NEAR CLIMO TUE WITH LOWS RUNNING SLIGHTLY ABOVE CLIMO. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 3 AM SUNDAY...PERIOD CONTINUES TO LOOK UNSETTLED WITH PIEDMONT TROUGH AND SEA BREEZE BEING QUITE ACTIVE. PATTERN ALOFT WILL RANGE FROM WEAK TROUGHING TO ZONAL FLOW INTO THE WEEKEND BEFORE MID LEVEL RIDGE STARTS TO BUILD OVER THE SOUTHEAST. FORECAST SOUNDINGS SHOW PLENTY OF DEEP MOISTURE IN PLACE FOR THE WEEK WITH PRECIPITABLE WATER VALUES CLOSE TO AND EVEN EXCEEDING 2 INCHES. THERE WILL BE SEVERAL WEAK SHORTWAVES CROSSING THE SOUTHEAST DURING THE PERIOD. TIMING THESE IS DIFFICULT AT BEST BUT EACH WILL HAVE THE ABILITY TO ENHANCE DIURNAL CONVECTION. PRECIP CHANCES WILL REMAIN ELEVATED WITH POP VALUES RANGING FROM 40 TO 50 FOR MUCH OF THE PERIOD. TEMPERATURES WILL RUN ABOVE CLIMO THROUGH THE PERIOD. HIGHS WILL REGULARLY EXCEED 90 IN MOST AREAS WITH LOWS IN THE LOW TO MID 70S. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... AS OF 18Z...THE HRRR MODEL HAS BEEN PRETTY CONSISTENT IN BRINGING DOWN CONVECTION FROM THE MOREHEAD CITY REGION ACROSS THE BI-STATE REGION THIS AFTN. LATEST 88D TRENDS INDICATE CONVECTION HAS INCHED CLOSER BUT REMAINS ISOLATED IN COVERAGE. AT THIS PACE...THE ILM TERMINAL MAY EXPERIENCE A CLAP OF THUNDER WITH AN OUTSIDE SHOT FOR THE MYRTLES TO EXPERIENCE CONVECTION PRIOR TO THE DAYS INSOLATION COMING TO AN END. LOOK FOR POSSIBLE MVFR VISIBILITIES IN THE TSHOWERS. FOR TONIGHT...VFR WITH A PARTLY CLOUDY SKY WITH THE EXCEPTION OF POSSIBLE MVFR CONDITIONS FROM REDUCED VSBY FROM FOG AFTER MIDNIGHT. FOR MONDAY...BECOMING VFR WITH ISOLATED POPS BY LATE MORNING. EXTENDED OUTLOOK...VFR MONDAY. AFTERNOON AND EVENING SHOWERS EXPECTED TUESDAY THROUGH FRIDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1130 AM SUNDAY...BROAD SFC LOW PARTIALLY ENCOMPASSING THE ILM COASTAL WATERS...IS PROGGED TO PUSH OFFSHORE THIS AFTERNOON WHILE THE FRONTAL BOUNDARY SINKS FURTHER SOUTHWARD IN ITS WAKE. WILL CONTINUE THE WINDS TRANSITIONING FROM A WNW-NNW TO NNE-ENE AS THE SFC RIDGING FROM THE NORTHEAST WORKS ITS WAY SW ACROSS THE CAROLINAS THIS AFTN AND TONIGHT. COULD SEE A SOLID 15 KT TONITE ACROSS THE ILM NC WATERS FROM THE BRIEF SFC PG TIGHTENING AND ASSOCIATED WEAK POST FRONTAL SURGE. SIGNIFICANT SEAS 2 TO 3 FT...WITH A FEW 4 FOOTERS POSSIBLE ACROSS THE ILM NC WATERS FROM CAPE FEAR NORTHWARD TONIGHT. PREVIOUS DISCUSSION................................. AS OF 3 AM SUNDAY...WEST TO NORTHWEST WINDS OF 10 TO 15 KT AROUND DAYBREAK WILL BECOME NORTH TO NORTHEAST TODAY AND A LITTLE MORE EASTERLY TONIGHT. SEAS OF 3 FT OR LESS ARE EXPECTED THROUGH THE PERIOD. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 3 AM SUNDAY...NORTHEAST FLOW AT THE START OF THE PERIOD WILL SLOWLY VEER TO EASTERLY DURING MON AS HIGH OVER NEW ENGLAND MOVES OFF THE COAST. GRADIENT WILL BE SUCH THAT SPEEDS REMAIN 10 TO 15 KT WITH SEAS 1 TO 3 FT. BERMUDA HIGH BUILDS BACK WEST ON TUE WITH SOUTHEAST FLOW IN THE MORNING BECOMING SOUTHWEST BY TUE EVENING. SPEEDS WILL REMAIN IN THE 10 TO 15 KT RANGE WITH 1 TO 3 FT SEAS CONTINUING. LONG TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 3 AM SUNDAY...BERMUDA HIGH WILL MAINTAIN SOUTHWEST FLOW OVER THE WATERS THROUGH THE PERIOD. SPEEDS WILL BE IN THE 10 TO 15 KT RANGE FOR MUCH OF THE PERIOD BUT COULD PERIODICALLY EXCEED 15 KT...ESPECIALLY ALONG THE COAST. SEAS W TO 3 FT ON WED WILL BUILD TO 2 TO 4 FT THU AS SOUTHERLY SWELL STARTS TO BECOME A LITTLE MORE PROMINENT. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...III NEAR TERM...DCH/RAN SHORT TERM...III LONG TERM...III AVIATION...DCH/DL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
310 AM EDT SUN JUN 22 2014 .SYNOPSIS...A SURFACE FRONT WILL PUSH SOUTHEAST THROUGH CENTRAL NORTH CAROLINA THIS MORNING. WEAK HIGH PRESSURE WILL THEN EXTEND OVER THE AREA THROUGH EARLY MONDAY. A SURFACE TROUGH OF LOW PRESSURE WILL RETURN TUESDAY THROUGH MIDWEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 310 AM SUNDAY... A WEAK/WAVY FRONTAL ZONE IS DRAPED ACROSS THE CWA THIS MORNING...THOUGH THE TRUE AIRMASS CHANCE REMAINS TO THE NORTH ACROSS CENTRAL VA. ALOFT WATER VAPOR IMAGERY SHOWS VARIOUS SMALL DISTURBANCES WITHIN BROAD CYCLONIC FLOW OVER THE EAST COAST. THE FRONT WILL SINK SOUTH OVER SC TODAY AND EVENTUALLY DISSIPATE AS HIGH PRESSURE OVER THE NORTHEAST NOSES INTO THE AREA. WITH THE PRIMARY AXIS OF LOW-LEVEL CONVERGENCE SOUTH OF THE AREA TODAY AND LOWER PW AIR FILTERING IN FROM THE NORTH...ESPECIALLY OVER THE CENTRAL AND WESTERN PIEDMONT...POPS WILL BE MUCH LOWER THAN THE PAST COUPLE OF DAYS. DEWPOINTS WILL REMAIN NEAR 70 OVER THE COASTAL PLAIN AND MLCAPE MAY REACH 1000 J/KG. MOST GUIDANCE FOCUSES QPF OVER THE COASTAL PLAIN AND THE SPC STORM SCALE ENSEMBLE SHOWS THE MOST ACTIVITY ACROSS THE NORTHERN COASTAL PLAIN....WHERE SLIGHT CHANCE POPS WILL BE FOCUSED. LOW-LEVEL THICKNESSES WILL BE DOWN ABOUT 10- 15M FROM YESTERDAY...THOUGH LOCATIONS IN THE NORTHEAST WILL FEEL THE EFFECTS A LITTLE MORE...WITH HIGHS IN THE MID 80S NORTH TO LOWER 90S SOUTH. HIGH PRESSURE NOSES INTO THE AREA TONIGHT WITH THE POTENTIAL FOR SOME STRATUS TO DEVELOP WITH A WEAK EAST-SOUTHEASTERLY LOW-LEVEL FLOW. LOWS IN THE MID TO UPPER 60S. && .SHORT TERM /MONDAY AND MONDAY NIGHT/... AS OF 310 AM SUNDAY... RIDGING ALOFT WILL BUILD OVER THE SOUTHEAST US ON MONDAY AS THE HIGH EXTENDING INTO THE AREA FROM NEW ENGLAND BEGINS TO RETREAT. MODELS ARE FAIRLY ACTIVE OVER WESTERN NC AS PW RETURNS TO ABOVE 1.5 INCHES. THE WESTERN PIEDMONT WOULD BE THE FAVORED AREA FOR WIDELY SCATTERED AFTERNOON STORMS GIVEN WEAK WESTERLY STEERING FLOW AND LACK OF SIGNIFICANT FORCING. HIGHS AGAIN RIGHT AROUND NORMAL IN THE 86-90 RANGE. LOWS 66-70. && .LONG TERM /TUESDAY THROUGH SATURDAY/... AS OF 310 AM SUNDAY... RETURN FLOW WILL BE ONGOING WITH SUPPRESSIVE SHORT WAVE MID LEVEL RIDGING SHIFTING EAST ON TUESDAY. THIS WILL LEAD TO INCREASED CONVECTIVE COVERAGE...A LITTLE MORE SO IN THE WEST...TUESDAY AFTERNOON AS HIGHS FLIRT WITHIN A DEGREE OR TWO OF 90. A SHORT WAVE TROF AND ASSOCIATED SURFACE FRONT WILL BE MOVING ACROSS THE AREA TUESDAY NIGHT/WEDNESDAY. AS SUCH...THE BEST CHANCE FOR WIDESPREAD CONVECTION WILL BE WEDNESDAY...ESPECIALLY IF THE FRONT AND SHORT WAVE MOVE THROUGH DURING THE HEAT OF THE DAY...WHICH WILL SPORT HIGHS MOSTLY IN THE LOWER 90S. HEADING INTO THE LATE WEEK...A LOW AMPLITUDE UPPER RIDGE WILL BUILD OVER THE AREA...WITH SOME MID LEVEL DRYING AND CAPPING TO LIMIT CONVECTION TO SOME DEGREE. HIGHS WILL STILL BE REACHING THE LOWER 90S EACH DAY...HOWEVER...AND WITH ABUNDANT LOW LEVEL MOISTURE... SCATTERED DIURNAL STORMS ARE EXPECTED EACH DAY. ACTIVITY WILL BE MORE FAVORED IN THE AREAS DRIVEN BY DIFFERENTIAL HEATING OFF THE EASTERN SLOPES AND IN THE EAST IN THE VICINITY OF LOW LEVEL CONVERGENCE PROVIDED BY LEE TROFFING AND PERHAPS SOME INLAND SEA BREEZE PENETRATION. MINS THROUGH THE EXTENDED WILL RANGE FROM THE UPPER 60S TO LOWER 70S. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... AS OF 140 AM SUNDAY... THE LAST REMAINING STORMS HAVE DIED OFF EARLY THIS MORNING...THOUGH WITH A CONTINUED HUMID AIRMASS...ADDITIONAL ISOLATED SHOWERS OR STORMS MAY STILL POP UP. LOW CLOUDS AND FOG ARE EXPECTED TO DEVELOP THIS MORNING...THOUGH THE SPOTTY NATURE OF STORMS LAST EVENING MAE IT DIFFICULT TO PINPOINT WHICH SITES WILL BE MOST ADVERSELY IMPACTED. IFR CONDITIONS HAVE ALREADY DEVELOPED AT KFAY...AMD RAP FORECAST SOUNDINGS SHOW IFR STRATUS DEVELOPING AT KRDU AND KRWI BY AS EARLY AS 08Z. CONFIDENCE IN STRATUS IS LOWER AT KGSO AND KINT WHERE RAP SOUNDINGS SHOW ONLY A BRIEF PERIOD JUST PRIOR TO 12Z. AS STRATUS LIFTS AND SCATTERS LATE THIS MORNING...VFR CONDITIONS WILL REDEVELOP AND ARE...FOR THE MOST PART...EXPECTED TO CONTINUE THROUGH THE REMAINDER OF THE DAY. A WEAK FRONTAL ZONE SETTLE SOUTH OVER SC WILL GIVE WAY TO A LIGHT NORTH-NORTHEASTERLY WIND...WITH JUST A SLIGHT CHANCE OF A FEW ISOLATED SHOWERS AND STORMS DURING THE AFTERNOON. LONG TERM: AFTER A RELATIVE LULL IN DIURNAL CONVECTION SUNDAY AND MONDAY...CHANCES WILL INCREASE FOR SHOWERS AND THUNDERSTORMS FOR MIDWEEK. THERE WILL BE A CHANCE FOR FOG/LOW STRATUS EACH MORNING TUESDAY THROUGH THURSDAY. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...CBL NEAR TERM...BLS SHORT TERM...BLS LONG TERM...MLM AVIATION...ELLIS/BLS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
140 AM EDT SUN JUN 22 2014 .SYNOPSIS..A SURFACE FRONT WILL PUSH SOUTHEAST THROUGH CENTRAL NORTH CAROLINA TONIGHT. WEAK HIGH PRESSURE WILL EXTEND OVER THE AREA THROUGH EARLY MONDAY. A SURFACE TROUGH OF LOW PRESSURE RETURNS TUESDAY THROUGH MIDWEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 920 PM SATURDAY... A BUSY AFTERNOON AND EVENING WITH MULTIPLE CLUSTERS OF MULTICELLULAR CONVECTION... MUCH OF IT QUITE STRONG BUT GENERALLY JUST BELOW SEVERE LIMITS. THE LATEST SURFACE ANALYSIS SHOWS A SURFACE LOW OVER CENTRAL NC WITH A WEAK CONVERGENCE ZONE RUNNING TO ITS EAST AND WEST... WHILE A MORE SUBSTANTIAL BACKDOOR FRONT EXTENDS THROUGH CENTRAL VA. A VERY WARM/MOIST (PW 1.5-2.0 IN.) AND UNSTABLE AIR MASS PERSISTS OVER NC WITH MLCAPE STILL AT 1500-2000 J/KG... ALTHOUGH CINH HAS GROWN QUICKLY IN RECENT HOURS... AND LOW LEVEL LAPSE RATES HAVE LOWERED IN PART BY THE NUMEROUS STORMS AND MULTIPLE OUTFLOWS. SEVERAL OF THE STORMS NEAR THE WEAK CONVERGENCE ZONE EXHIBITED WEAK BUT DEEP ROTATION EARLIER THIS EVENING AS THEY FED ON THIS VORTICITY... HOWEVER THIS TOO HAS WANED. THE RECENT RAP MODEL RUN SHOWS STEADY MID LEVEL DRYING OVERNIGHT ESPECIALLY IN THE NW CWA WITH PW FALLING NEAR 1.2 IN... ALTHOUGH VALUES HOLD UP IN THE ERN/SE CWA WITH CONTINUED TALL SKINNY MARGINAL CAPE AND WEAK MBE MOVEMENT EXPECTED. SO EVEN AFTER THE NUMEROUS STORMS IN THE COASTAL PLAIN SHIFT SLOWLY EAST OUT OF THE CWA SOON AFTER MIDNIGHT... ADDITIONAL ISOLATED STORMS OR STORM CLUSTERS FROM THE TRIANGLE EASTWARD CANNOT BE RULED OUT THROUGH THE NIGHT... AND A FEW OF THESE COULD PRODUCE LOCALLY HEAVY DOWNPOURS DUE TO THEIR SLOW MOVEMENT. OTHERWISE... EXPECT AREAS OF FOG AND STRATUS TO FORM ESPECIALLY ACROSS THE NORTHERN HALF WHERE PARTIAL CLEARING AND MOIST GROUND WILL FOSTER LOW CLOUD DEVELOPMENT... A SCENARIO CORROBORATED BY LATEST HRRR. LOWS 68-73... FOLLOWING THE LATEST GLAMP GUIDANCE AND OBSERVED TRENDS. -GIH && .SHORT TERM /SUNDAY AND SUNDAY NIGHT/... AS OF 230 PM SATURDAY... SURFACE BOUNDARY/TROUGH IS EXPECTED TO SETTLE SOUTH OF THE AREA ON SUNDAY AS WEAK SURFACE HIGH PRESSURE OFF THE MID-ATLANTIC COAST RIDGES SOUTHEASTWARD INTO THE AREA. ALOFT...NWLY FLOW ALOFT WILL PREVAIL FOR ONE LAST PERIOD...WITH CENTRAL NC REMAINING POISED TO SEE ADDITIONALLY SHORTWAVE IMPULSES MOVE THROUGH THE AREA. ASSOCIATED DPVA COUPLED WITH DIURNAL HEATING COULD SUPPORT ISOLATED TO SLIGHT CHANCE OF SHOWER/STORM JUST ABOUT ANYWHERE ACROSS THE FORECAST AREA. LOW-LEVEL NELY FLOW WILL COOL THINGS OFF A BIT...WITH 12Z LOW-LEVEL THICKNESSES SUNDAY MORNING OF 1395M A GOOD 10 METERS BELOW TYPICAL LATE JUNE THICKNESS VALUES. HIGHS RANGING MID 80S NORTH TO NEAR 90 SOUTH. HEIGHTS ALOFT BEGIN TO INCREASE OVER THE AREA SUNDAY NIGHT. SURFACE RIDGE LOOKS TO HOLD IN PLACE BEFORE SUCCUMBING TO RETURN FLOW DURING THE DAY ON MONDAY. MODELS CONTINUE HINT AT THE POTENTIAL FOR SOME MORNING STRATUS LATE TOWARDS DAYBREAK. LOWS IN THE MID TO UPPER 60S. && .LONG TERM /MONDAY THROUGH SATURDAY/... AS OF 210 PM SATURDAY... HIGH PRESSURE RIDGING DOWN THE EAST COAST WILL GRADUALLY SHIFT OFFSHORE DURING THE DAY ON MONDAY...ALLOWING MOISTURE TO BEGIN TO INCREASE ON ITS BACK SIDE WITHIN THE RETURN FLOW. THEREFORE... PRECIP CHANCES WILL INCREASE SLIGHTLY ON MONDAY...MOST NOTICEABLY ACROSS THE WEST WITHIN THE BEST RETURN FLOW. NEVERTHELESS...COVERAGE IS EXPECTED TO BE ISOLATED TO WIDELY SCATTERED AT BEST AS A MID LEVEL RIDGE BUILDS OVERHEAD. HIGHS ARE EXPECTED TO BE IN THE MID/UPPER 80S TO NEAR 90 DEGREES...WITH OVERNIGHT LOWS GENERALLY IN THE MID/UPPER 60S TO NEAR 70 DEGREES. PRECIP CHANCES...MOSTLY DIURNAL IN NATURE...WILL BEGIN TO INCREASE EVEN MORE ON TUESDAY AND THEN PERSIST FOR THE REMAINDER OF THE LONG TERM AS MOISTURE CONTINUES TO INCREASE WITHIN THE RETURN FLOW THAT SETS UP ON THE BACKSIDE OF THE DEPARTING HIGH. IN ADDITION...FLOW ALOFT WILL BECOME SOUTHWESTERLY (THUS INCREASING DEEP LAYER MOISTURE) AS LARGE SCALE TROUGHING MOVES OVER THE GREAT LAKES/MS RIVER VALLEY. SHORTWAVE TROUGHING WILL THEN PROGRESS EAST OVER THE REGION WEDNESDAY INTO THURSDAY...PROVIDING ADDITIONAL FORCING FOR PRECIP. RIDGING ALOFT (ALTHOUGH RATHER FLAT) WILL BUILD BACK OVER THE AREA LATE INTO THE WEEK AND INTO EARLY NEXT WEEKEND...ALLOWING SOME MID LEVEL DRYING TO OCCUR. NEVERTHELESS...MODERATE TO STRONG INSTABILITY WILL RESULT IN CONTINUED PRECIP CHANCES...ALTHOUGH COVERAGE MAY BE SLIGHTLY LESS. HIGHS WILL GENERALLY IN THE UPPER 80S TO LOWER 90S TO START THE PERIOD WITH LOW TO MID 90S EXPECTED BY THE END OF THE WEEK. OVERNIGHT LOWS WILL MOSTLY BE IN THE UPPER 60S TO LOWER 70S. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... AS OF 140 AM SUNDAY... THE LAST REMAINING STORMS HAVE DIED OFF EARLY THIS MORNING...THOUGH WITH A CONTINUED HUMID AIRMASS...ADDITIONAL ISOLATED SHOWERS OR STORMS MAY STILL POP UP. LOW CLOUDS AND FOG ARE EXPECTED TO DEVELOP THIS MORNING...THOUGH THE SPOTTY NATURE OF STORMS LAST EVENING MAE IT DIFFICULT TO PINPOINT WHICH SITES WILL BE MOST ADVERSELY IMPACTED. IFR CONDITIONS HAVE ALREADY DEVELOPED AT KFAY...AMD RAP FORECAST SOUNDINGS SHOW IFR STRATUS DEVELOPING AT KRDU AND KRWI BY AS EARLY AS 08Z. CONFIDENCE IN STRATUS IS LOWER AT KGSO AND KINT WHERE RAP SOUNDINGS SHOW ONLY A BRIEF PERIOD JUST PRIOR TO 12Z. AS STRATUS LIFTS AND SCATTERS LATE THIS MORNING...VFR CONDITIONS WILL REDEVELOP AND ARE...FOR THE MOST PART...EXPECTED TO CONTINUE THROUGH THE REMAINDER OF THE DAY. A WEAK FRONTAL ZONE SETTLE SOUTH OVER SC WILL GIVE WAY TO A LIGHT NORTH-NORTHEASTERLY WIND...WITH JUST A SLIGHT CHANCE OF A FEW ISOLATED SHOWERS AND STORMS DURING THE AFTERNOON. LONG TERM: AFTER A RELATIVE LULL IN DIURNAL CONVECTION SUNDAY AND MONDAY...CHANCES WILL INCREASE FOR SHOWERS AND THUNDERSTORMS FOR MIDWEEK. THERE WILL BE A CHANCE FOR FOG/LOW STRATUS EACH MORNING TUESDAY THROUGH THURSDAY. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...CBL NEAR TERM...HARTFIELD SHORT TERM...CBL LONG TERM...KRD AVIATION...ELLIS/BLS
AREA FORECAST DISCUSSION
NWS TULSA OK
925 PM CDT MON JUN 23 2014 ...UPDATE... .DISCUSSION... PRECIP HAS FOR THE MOST PART SHIFTED EAST OF THE CWA THIS EVENING. THE REMAINING FEW SHOWERS WERE LOCATED ACROSS FAR EASTERN OKLAHOMA INTO PARTS OF NORTHEAST OKLAHOMA. THESE SHOWERS SHOULD CONTINUE TO DISSIPATE AND SHIFT EASTWARD OVER THE NEXT FEW HOURS. ACROSS THE REST OF EASTERN OKLAHOMA...SKIES WERE CLEARING OUT WITH LIGHT WINDS OBSERVED. OVERNIGHT TONIGHT...MOSTLY CLEAR TO PARTLY CLOUDY SKIES SHOULD BE COMMON ACROSS THE REGION. LATEST LOCAL IN-HOUSE MODEL AND THE HRRR CONTINUE TO INDICATE THAT THE CONVECTION OVER EASTERN COLORADO AND THE TEXAS PANHANDLE SHOULD STAY TO THE NORTH AND WEST OF THE REGION. THUS...WILL NOT CARRY POPS AFTER 06Z. THE LIGHT WINDS AND MOSTLY CLEAR TO PARTLY CLOUDY SKIES WILL HOWEVER CREATE THE POTENTIAL FOR AREAS OF FOG TO BE POSSIBLE AFTER THE RECENT RAINS. HAVE EXTENDED THE FOG POTENTIAL A BIT FURTHER WEST AND SOUTH ACROSS THE REGION. TEMPERATURES OVERNIGHT LOOK TO BE COOLER COMPARED TO PREVIOUS NIGHTS AND HAVE ONLY MADE A FEW TWEAKS FOR THE EVENING UPDATE. && .PRELIMINARY POINT TEMPS/POPS... TUL 63 89 67 88 / 10 10 20 30 FSM 65 89 67 90 / 20 10 20 30 MLC 64 89 68 89 / 10 10 20 30 BVO 61 88 64 86 / 10 10 20 30 FYV 60 85 61 85 / 20 10 20 30 BYV 61 85 61 86 / 20 10 20 30 MKO 62 88 66 87 / 10 10 20 30 MIO 61 86 64 86 / 10 10 20 30 F10 63 88 67 87 / 10 10 20 30 HHW 66 89 69 90 / 10 10 20 30 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...20 AVIATION.....18
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
201 AM MDT SUN JUN 22 2014 .UPDATE... ISSUED AT 901 PM MDT SAT JUN 21 2014 IT LOOKS LIKE THE SEVERE THREAT IS TAPERING OFF SO HAVE ALLOWED THE SVR TSTM WATCH TO EXPIRE AS SCHEDULED. ISOLD-SCT THUNDERSTORMS ARE STILL EXPECTED OVERNIGHT AS MODELS INDICATED ABUNDANT MID LEVEL INSTABILITY. LOCALLY HEAVY RAIN WILL BE POSSIBLE OVER PARTS OF WESTERN SOUTH DAKOTA. && .SHORT TERM...THIS EVENING THROUGH SUNDAY NIGHT ISSUED AT 210 PM MDT SAT JUN 21 2014 A BROAD NORTH/SOUTH PRE-FRONTAL SURFACE TROUGH ACROSS THE WESTERN AND CENTRAL DAKOTAS DOMINATES THE SURFACE MAP THIS AFTERNOON. THE TROUGH EXTENDS SOUTHWARD FROM A NEARLY STATIONARY LOW OVER SOUTH CENTRAL CANADA. A WEAK COLD FRONT ALSO EXTENDS SOUTHWARD FROM THIS LOW THROUGH EASTERN MONTANA AND NORTH CENTRAL WYOMING. DEWPOINT TEMPERATURES AHEAD OF THE TROUGH IN CENTRAL AND EASTERN SOUTH DAKOTA ARE IN THE MID 60S...WHILE DEWPOINTS BEHIND THE COLD FRONT DROP INTO THE MID 40S. ONLY VERY WEAK UPPER LEVEL IMPULSES ARE DISCERNABLE IN THE MOSTLY ZONAL FLOW ACROSS THE NORTHERN PLAINS TODAY. SOME WEAK CONVECTION HAS FIRED UP ALONG THE COLD FRONT IN NORTHEAST WYOMING AND EASTERN MONTANA BUT IR IMAGERY INDICATES MINIMAL VERTICAL DEVELOPMENT. A WEAKER SURFACE LOW RESIDES OVER EASTERN COLORADO...SUPPORTING A MOSTLY STATIONARY EAST-WEST WARM FRONT BOUNDARY ALONG THE NEBRASKA SOUTH DAKOTA BORDER. LITTLE OR NO CONVECTIVE DEVELOPMENT HAS TAKEN PLACE ALONG THIS BOUNDARY. MORNING SOUNDINGS AT BOTH UNR AND LBF INDICATE A STRONG CAP BELOW 700 MB WITH A DRY LAYER JUST OFF THE SURFACE AND THEN UNSTABLE LAPS RATES AT MID LEVELS. TRIGGER TEMPERATURES AT BOTH LOCATIONS ARE IN THE MID 80S. THIS EVENING...THE KEY FOR LOCATING THE CONVECTIVE DEVELOPMENT THIS EVENING WILL BE THE LOCATION OF THE VERY DIFFUSE BOUNDARY COINCIDING WITH THE WESTERN DAKOTAS TROUGH. THE HRRR GUIDANCE MAINTAINS A LINE OF THUNDERSTORMS FROM THE SOUTHWEST CORNER OF SOUTH DAKOTA TO CENTRAL SOUTH DAKOTA AS WELL AS AN AREA OF POST FRONTAL STORMS OVER NORTHEAST WYOMING. THE COMBINATION OF MID LEVEL INSTABILITY...LARGE CAPE VALUES OVER 2000 J/KG AND ADEQUATE BULK SHEAR OF 30 TO 40 KTS WILL SUPPORT SUPERCELL DEVELOPMENT CAPABLE OF PRODUCING STRONG WINDS GUSTS AND LARGE HAIL. IT APPEARS AT THIS TIME THAT MOST OF THE ACTION THIS AFTERNOON WILL TAKE PLACE EAST AND SOUTH OF THE BLKHLS REGION WITH SOMEWHAT WEAKER ACTIVITY OVER NORTHEAST WYOMING. OVERNIGHT TONIGHT...THE SURFACE FRONT WILL SLOWLY SHIFT SOUTH AND EAST DURING THE LATE EVENING. STRONG TO SEVERE STORMS ARE LIKELY ALONG OR NEAR THE FRONTAL BOUNDARY AS IT CONTINUES EASTWARD INTO CENTRAL SOUTH DAKOTA BY 04Z. A WEAK UPPER LEVEL IMPULSE IS EXPECTED TO MOVE INTO NORTHEAST WYOMING AND AND A BROAD AREA OF ISENTROPIC UPGLIDE IS FORECAST TO DEVELOP OVER THE SHALLOW COOL AIR IN WESTERN SOUTH DAKOTA AND NORTHEAST WYOMING MOSTLY SOUTH OF US HWY 212 RESULTING IN A STRATIFORM PRECIP EVENT FOR AREAS STRETCHING FROM AROUND THE BLKLHS TO THE MORVR. TEMPERATURES WILL COOL INTO THE 50S TO LOWER 60S. SUNDAY...OVERCAST SKIES AND STRATIFORM PRECIP SHOULD BE ONGOING BEFORE SUN RISE IN NORTHEAST WYOMING AND THE BLKHLS AREA AND SPREAD TO THE MORVR BEFORE NOON. ISOLATED THUNDERSTORMS ARE POSSIBLE...BUT THESE SHOULD BE PRETTY WEAK. A MODERATE NORTHWEST BREEZE WILL ACCOMPANY THE LIGHT RAIN. THE LIGHT RAIN IS EXPECTED TO BEGIN TAPERING OFF BY 00Z AS THE COOL AIRMASS PUSHES FURTHER SOUTH AND EAST. COOLER AIR WILL MOVE INTO THE NORTHERN PLAINS...WITH HIGH TEMPERATURES 10 TO 15 DEGREES COOLER THAN TODAY...ONLY IN THE MID 60S TO UPPER 70S. SUNDAY NIGHT...DISSIPATING PRECIPITATION AND SOME LINGERING CLOUD COVER WILL KEEP TEMPERATURES FROM DROPPING BELOW THE LOWER 50S IN MOST PLACES...UPPER 40S IN NORTHEAST WYOMING AND THE BLKHLS. && .LONG TERM...MONDAY THROUGH SATURDAY ISSUED AT 210 PM MDT SAT JUN 21 2014 AN UPPER LEVEL RIDGE OVER THE NORTHERN ROCKIES WILL SLOWLY EXPAND EASTWARD MONDAY THROUGH THURSDAY. BY THURSDAY...AN UPPER LEVEL TROUGH WILL HAVE DEVELOPED OVER SOUTHWEST CANADA/NORTHWEST US. THE RESULT WILL BE WEST/NORTHWEST FLOW ALOFT EARLY IN THE PERIOD TRANSITIONING TO SOUTHWEST FLOW ALOFT BY THE END OF THE WEEK. A PARADE OF SHORTWAVES WILL BRING TSRA AT TIMES...ESPECIALLY DURING THE AFTERNOON/EVENING HOURS GIVEN SLOWLY BUILDING THERMAL RIDGE OVER THE NORTHERN PLAINS AND SUBSEQUENT SLIGHTLY HIGHER MLCIN VALUES. GFS/ECMWF ARE IN GENERAL AGREEMENT...BUT BOTH HINT AT POSSIBLE BACK DOOR COOL FRONTS TUESDAY OR WEDNESDAY FOR THE SD PLAINS GIVEN PROXIMITY OF UPPER LOW OVER HUDSON BAY. DIDN/T DEVIATE MUCH FROM GUIDANCE VALUES FOR TEMPERATURES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 158 AM MDT SUN JUN 22 2014 SCATTERED SHOWERS AND THUNDERSTOMRS WILL CONTINUE OVERNIGHT... RESULTING IN RATHER WIDESPREAD PRECIPITATION COVERAGE ACROSS NORTHEASTERN WY/WESTERN SD. THIS AREA OF PRECIPITATION WILL CAUSE MVFR CIGS/VSBYS. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ UPDATE...10 SHORT TERM...CARPENTER LONG TERM...HELGESON AVIATION...MLS
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1246 PM CDT SUN JUN 22 2014 .UPDATE... UPDATED FOR 18Z AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 1046 AM CDT SUN JUN 22 2014/ UPDATE... MIDMORNING GOES IR IMAGERY SHOWED A COUPLE OF MCS THIS MORNING... OVER EASTER NE AND IA AND ANOTHER OVER NORTH TX. NEITHER MCS WAS UPSTREAM OF THE MIDSOUTH...AND THE TX MCS HAD REARWARD PROPAGATION COMPONENT. NEARER TO THE MIDSOUTH...SOME MIDLEVEL CLOUD COOLING WAS NOTED ON IR OVER CENTRAL AND NORTH MS...PERHAPS AN INDICATION OF ENHANCED MIDLEVEL LIFT FROM A WEAK 250MB JET STREAK OVER THE ARKLAMISS REGION. TODAY/S RAIN CHANCES FOR THE MIDSOUTH APPEAR A LITTLE MORE LIMITED THAN SATURDAY...GIVEN THE LACK OF A DISTINCT MCS OR MIDLEVEL SHORTWAVE TROF. 13Z HRRR MODEL DEPICTED AFTERNOON THUNDERSTORM COVERAGE TO BE ISOLATED AT BEST. HOWEVER...12Z NAM BUFR SOUNDINGS SHOW THE BOUNDARY LAYER UNCAPPED BY 18Z...WITH SURFACE BASED CAPE IN EXCESS OF 2000 J/KG AREAWIDE. IN THE ABSENCE OF A SHORTWAVE TROF OR MCV...MESOSCALE PROCESSES /DIFFERENTIAL HEATING...OUTFLOW BOUNDARY INTERACTIONS/ WILL LIKELY DETERMINE WHERE AND IF THUNDERSTORMS INITIATE AND SUBSEQUENTLY EVOLVE. MOST RECENT FORECAST UPDATED INCLUDED MINOR ADJUSTMENTS TO TIMING OF POPS AND TO EDGE AFTERNOON TEMPS UP A BIT NORTH AND EAST OF THE MEMPHIS METRO. PWB PREV DISCUSSION... /ISSUED 633 AM CDT SUN JUN 22 2014/ DISCUSSION... UPDATED FOR THE 12Z AVIATION DISCUSSION PREV DISCUSSION... /ISSUED 352 AM CDT SUN JUN 22 2014/ DISCUSSION... THE LONGEST DAY OF THE YEAR HAS COME TO AN END AND ITS ANOTHER QUIET SUMMER NIGHT ACROSS THE MIDSOUTH. TEMPERATURES HAVE FALLEN INTO THE UPPER 60S IN THE COOLEST LOCATIONS ACROSS THE MIDSOUTH WITH MOST AREAS IN THE LOW TO MIDDLE 70S. MORNING LOWS SHOULD BE IN THE UPPER 60S TO NEAR 70 DEGREES AREA WIDE. PATCHY FOG HAS DEVELOPED...AND VISIBILITY HAS DROPPED AS LOW AS 1/4 MILE IN ALCORN COUNTY MISSISSIPPI...BUT THAT IS THE EXCEPTION. MOST AREAS ARE ONLY EXPERIENCING SLIGHT REDUCTIONS TO VISIBILITY IF ANY. WILL MONITOR ADDITIONAL FOG DEVELOPMENT...BUT DO NOT ANTICIPATE THE NEED FOR ANY KIND OF ADVISORY. WE WILL LIKELY SEE ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS DEVELOP THIS AFTERNOON. WIDESPREAD SEVERE STORMS ARE NOT EXPECTED...BUT ISOLATED SEVERE STORMS AS WELL AS NUMEROUS STRONG STORMS ARE POSSIBLE. THE MAIN THREAT FROM ANY STRONG TO SEVERE STORMS WILL BE WINDS...MAINLY IN THE FORM OF WET MICROBURSTS. GUIDANCE SUGGESTS STORMS WILL DEVELOP QUICKLY AFTER SUNRISE. THE GFS SHOWS A FAIRLY DECENT VORT MAX TRACKING OUT OF SOUTHERN ARKANSAS INTO CENTRAL MISSISSIPPI THIS AFTERNOON...AND THERE IS SOME INDICATION ON SATELLITE OF THIS FEATURE IN SOUTHERN ARKANSAS RIGHT NOW. THIS MAY ENHANCE STORMS ACROSS NORTH MISSISSIPPI...BUT FOR THE MOST PART WE ARE NOT TARGETING ANY SPECIFIC PORTION OF THE MIDSOUTH FOR ENHANCED COVERAGE OR STRENGTH OF STORMS. DEW POINTS IN THE LOW TO MIDDLE 70S WILL HELP TO PRODUCE A VERY UNSTABLE ENVIRONMENT FEATURING CAPE VALUES INTO THE 2500-3000 J/KG RANGE THIS AFTERNOON AND LI`S BELOW -7C. MOISTURE LEVELS ALOFT ARE ALSO HIGH...BOTH LITTLE ROCK AND NASHVILLE AFTERNOON SOUNDINGS HAD PW VALUES AROUND 1.5 INCHES. AS A RESULT...HEAVY RAINFALL IS LIKELY. STORM MOTION WILL BE SLOW...LIKELY DRIFTING EAST TO SOUTHEAST SO ISOLATED FLOODING PROBLEMS ARE POSSIBLE. ENHANCED RAIN CHANCES WILL REMAIN IN THE FORECAST THROUGH MIDWEEK WITH THE GREATEST CHANCES MONDAY AFTERNOON THROUGH TUESDAY AFTERNOON AS A SEASONABLY STRONG SHORTWAVE TROUGH SHIFTS OUT OF THE CENTRAL/SOUTHERN PLAINS ACROSS THE MISSISSIPPI RIVER VALLEY. ONCE AGAIN...NO WIDESPREAD SEVERE STORMS ARE EXPECTED...BUT ANY STORMS ARE LIKELY TO BECOME STRONG WITH OUR CURRENT ATMOSPHERIC CONDITIONS AND ISOLATED SEVERE STORMS ARE POSSIBLE. DAMAGING WIND IS THE MOST LIKELY THREAT. HIGH TEMPERATURES SHOULD BE KEPT DOWN A BIT ESPECIALLY MONDAY AND TUESDAY. HIGHS MAY EVEN REMAIN IN THE LOW 80S IF THUNDERS STORMS AND CLOUDS ARE NUMEROUS. AFTER MIDWEEK...AS THE SHORTWAVE SHIFTS EAST OF THE MIDSOUTH A WEAK RIDGE AND SURFACE HIGH PRESSURE WILL TRY TO REASSERT ITS INFLUENCE ACROSS THE MIDSOUTH. EXPECT LESS RAIN THURSDAY INTO THE WEEKEND AND SLIGHTLY WARMER TEMPERATURES. GUIDANCE IS NOT IN PERFECT AGREEMENT WITH THIS SOLUTION. THE ECMWF FEATURES A STRONGER RIDGE CENTERED FARTHER NORTH AND WEST WHICH WOULD RESULT IN AN EVEN WARMER AND DRIER FORECAST FRIDAY THROUGH THE WEEKEND. FOR NOW WILL PLAY THE MIDDLE OF THE ROAD...HOLDING ONTO SLIGHT CHANCE TO LOW CHANCE POPS DURING THE END OF THE FORECAST PERIOD AND NEAR NORMAL TEMPERATURES. 30 && .AVIATION... 18Z TAF CYCLE AFTERNOON CONVECTION HAS ALREADY FIRED UP IN THE SOUTHERNMOST PORTION OF THE CWA WITH CAPE VALUES ALREADY EXCEEDING 3000 J/KG AT ALL SITES ACCORDING TO SPC MESOANALYSIS. CURRENT THINKING IS THAT NORTHERN MS WILL HAVE THE BEST CHANCE FOR AFTERNOON STORMS TODAY AS 500MB HEIGHT FALLS WILL BE THE GREATEST THERE. NONETHELESS...HAVE INCLUDED A VCTS AT ALL SITES UNTIL AFTER SUNSET TO ACCOUNT FOR THE UNCERTAINTY REGARDING TODAYS CONVECTION. WILL AMEND AS NECESSARY TO ACCOUNT FOR STORMS THAT MAY DEVELOP WITHIN THE VICINITY OF THE SITES. ZDM && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1046 AM CDT SUN JUN 22 2014 .UPDATE... MIDMORNING GOES IR IMAGERY SHOWED A COUPLE OF MCS THIS MORNING... OVER EASTER NE AND IA AND ANOTHER OVER NORTH TX. NEITHER MCS WAS UPSTREAM OF THE MIDSOUTH...AND THE TX MCS HAD REARWARD PROPAGATION COMPONENT. NEARER TO THE MIDSOUTH...SOME MIDLEVEL CLOUD COOLING WAS NOTED ON IR OVER CENTRAL AND NORTH MS...PERHAPS AN INDICATION OF ENHANCED MIDLEVEL LIFT FROM A WEAK 250MB JET STREAK OVER THE ARKLAMISS REGION. TODAY/S RAIN CHANCES FOR THE MIDSOUTH APPEAR A LITTLE MORE LIMITED THAN SATURDAY...GIVEN THE LACK OF A DISTINCT MCS OR MIDLEVEL SHORTWAVE TROF. 13Z HRRR MODEL DEPICTED AFTERNOON THUNDERSTORM COVERAGE TO BE ISOLATED AT BEST. HOWEVER...12Z NAM BUFR SOUNDINGS SHOW THE BOUNDARY LAYER UNCAPPED BY 18Z...WITH SURFACE BASED CAPE IN EXCESS OF 2000 J/KG AREAWIDE. IN THE ABSENCE OF A SHORTWAVE TROF OR MCV...MESOSCALE PROCESSES /DIFFERENTIAL HEATING...OUTFLOW BOUNDARY INTERACTIONS/ WILL LIKELY DETERMINE WHERE AND IF THUNDERSTORMS INITIATE AND SUBSEQUENTLY EVOLVE. MOST RECENT FORECAST UPDATED INCLUDED MINOR ADJUSTMENTS TO TIMING OF POPS AND TO EDGE AFTERNOON TEMPS UP A BIT NORTH AND EAST OF THE MEMPHIS METRO. PWB && .PREV DISCUSSION... /ISSUED 633 AM CDT SUN JUN 22 2014/ DISCUSSION... UPDATED FOR THE 12Z AVIATION DISCUSSION PREV DISCUSSION... /ISSUED 352 AM CDT SUN JUN 22 2014/ DISCUSSION... THE LONGEST DAY OF THE YEAR HAS COME TO AN END AND ITS ANOTHER QUIET SUMMER NIGHT ACROSS THE MIDSOUTH. TEMPERATURES HAVE FALLEN INTO THE UPPER 60S IN THE COOLEST LOCATIONS ACROSS THE MIDSOUTH WITH MOST AREAS IN THE LOW TO MIDDLE 70S. MORNING LOWS SHOULD BE IN THE UPPER 60S TO NEAR 70 DEGREES AREA WIDE. PATCHY FOG HAS DEVELOPED...AND VISIBILITY HAS DROPPED AS LOW AS 1/4 MILE IN ALCORN COUNTY MISSISSIPPI...BUT THAT IS THE EXCEPTION. MOST AREAS ARE ONLY EXPERIENCING SLIGHT REDUCTIONS TO VISIBILITY IF ANY. WILL MONITOR ADDITIONAL FOG DEVELOPMENT...BUT DO NOT ANTICIPATE THE NEED FOR ANY KIND OF ADVISORY. WE WILL LIKELY SEE ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS DEVELOP THIS AFTERNOON. WIDESPREAD SEVERE STORMS ARE NOT EXPECTED...BUT ISOLATED SEVERE STORMS AS WELL AS NUMEROUS STRONG STORMS ARE POSSIBLE. THE MAIN THREAT FROM ANY STRONG TO SEVERE STORMS WILL BE WINDS...MAINLY IN THE FORM OF WET MICROBURSTS. GUIDANCE SUGGESTS STORMS WILL DEVELOP QUICKLY AFTER SUNRISE. THE GFS SHOWS A FAIRLY DECENT VORT MAX TRACKING OUT OF SOUTHERN ARKANSAS INTO CENTRAL MISSISSIPPI THIS AFTERNOON...AND THERE IS SOME INDICATION ON SATELLITE OF THIS FEATURE IN SOUTHERN ARKANSAS RIGHT NOW. THIS MAY ENHANCE STORMS ACROSS NORTH MISSISSIPPI...BUT FOR THE MOST PART WE ARE NOT TARGETING ANY SPECIFIC PORTION OF THE MIDSOUTH FOR ENHANCED COVERAGE OR STRENGTH OF STORMS. DEW POINTS IN THE LOW TO MIDDLE 70S WILL HELP TO PRODUCE A VERY UNSTABLE ENVIRONMENT FEATURING CAPE VALUES INTO THE 2500-3000 J/KG RANGE THIS AFTERNOON AND LI`S BELOW -7C. MOISTURE LEVELS ALOFT ARE ALSO HIGH...BOTH LITTLE ROCK AND NASHVILLE AFTERNOON SOUNDINGS HAD PW VALUES AROUND 1.5 INCHES. AS A RESULT...HEAVY RAINFALL IS LIKELY. STORM MOTION WILL BE SLOW...LIKELY DRIFTING EAST TO SOUTHEAST SO ISOLATED FLOODING PROBLEMS ARE POSSIBLE. ENHANCED RAIN CHANCES WILL REMAIN IN THE FORECAST THROUGH MIDWEEK WITH THE GREATEST CHANCES MONDAY AFTERNOON THROUGH TUESDAY AFTERNOON AS A SEASONABLY STRONG SHORTWAVE TROUGH SHIFTS OUT OF THE CENTRAL/SOUTHERN PLAINS ACROSS THE MISSISSIPPI RIVER VALLEY. ONCE AGAIN...NO WIDESPREAD SEVERE STORMS ARE EXPECTED...BUT ANY STORMS ARE LIKELY TO BECOME STRONG WITH OUR CURRENT ATMOSPHERIC CONDITIONS AND ISOLATED SEVERE STORMS ARE POSSIBLE. DAMAGING WIND IS THE MOST LIKELY THREAT. HIGH TEMPERATURES SHOULD BE KEPT DOWN A BIT ESPECIALLY MONDAY AND TUESDAY. HIGHS MAY EVEN REMAIN IN THE LOW 80S IF THUNDERS STORMS AND CLOUDS ARE NUMEROUS. AFTER MIDWEEK...AS THE SHORTWAVE SHIFTS EAST OF THE MIDSOUTH A WEAK RIDGE AND SURFACE HIGH PRESSURE WILL TRY TO REASSERT ITS INFLUENCE ACROSS THE MIDSOUTH. EXPECT LESS RAIN THURSDAY INTO THE WEEKEND AND SLIGHTLY WARMER TEMPERATURES. GUIDANCE IS NOT IN PERFECT AGREEMENT WITH THIS SOLUTION. THE ECMWF FEATURES A STRONGER RIDGE CENTERED FARTHER NORTH AND WEST WHICH WOULD RESULT IN AN EVEN WARMER AND DRIER FORECAST FRIDAY THROUGH THE WEEKEND. FOR NOW WILL PLAY THE MIDDLE OF THE ROAD...HOLDING ONTO SLIGHT CHANCE TO LOW CHANCE POPS DURING THE END OF THE FORECAST PERIOD AND NEAR NORMAL TEMPERATURES. 30 && .AVIATION... 12Z TAF CYCLE VFR CONDITIONS SHOULD PERSIST FOR MUCH OF THE FORECAST PERIOD. SOME SCATTERED THUNDERSTORMS WILL MOVE ACROSS THE FORECAST AREA MAINLY DURING THE AFTERNOON HOURS. WINDS WILL BE FAIRLY LIGHT AND MAINLY FROM THE WEST FOR MUCH OF THE FORECAST PERIOD. ARS && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1028 PM CDT MON JUN 23 2014 .UPDATE... An outflow boundary continues to move southwest across the Concho Valley and North Edwards Plateau late this evening. Isolated thunderstorms that developed along this boundary earlier this evening have dissipated with the loss of heating. The main concern for the rest of tonight will be the potential for showers and thunderstorms to move in from the west towards daybreak. Thunderstorms are currently affecting portions of eastern New Mexico, with the strongest convection located across southeast New Mexico north of Carlsbad. Uncertainty exists regarding convective evolution and weather storms will organize into a southeast propagating MCS overnight. The Texas Tech WRF is the most aggressive model and brings a weakening band of convection into western sections after 4 AM, with activity dissipating across central sections through early morning. The latest NAM and HRRR show most of the convection remaining west of the forecast area. Given the uncertainty, kept chance POPs in the forecast generally west of a Haskell to Sonora line overnight and lowered POPs to slight chance elsewhere. Also tweaked temps and dewpoints to account for trends. && .PREV DISCUSSION... /ISSUED 618 PM CDT MON JUN 23 2014/ AVIATION... /00Z TAFS/ Expect VFR conditions at the terminals this evening into the early morning hours. Stratus will develop along the I-10 corridor during the morning hours Tuesday, going with MVFR CIGS at the KSOA and KJCT terminals after 10Z Tuesday. VFR conditions will return by 15Z Tuesday. Isolated thunderstorms will be possible around the KSJT terminal through mid evening and carrying VCTS through 03Z. A complex or two of storms will develop well west of the terminals later tonight and some of this activity may make it east into West Central Texas by Tuesday morning. Confidence is not high enough to put in the terminals and will watch radar and satellite trends this evening. PREV DISCUSSION... /ISSUED 344 PM CDT MON JUN 23 2014/ SHORT TERM... (Tonight and Tuesday) Showers and thunderstorms moved out of the area early this afternoon, leaving partly to mostly cloudy skies and a very humid air mass along with leftover outflow boundaries from the overnight into early morning thunderstorms. Aloft, a shortwave trough is moving east into New Mexico this afternoon helping to set off thunderstorms across the mountains of New Mexico. Thunderstorms were also developing across the mountains near and west of the Big Bend area in Texas. A few isolated thunderstorms could develop by late this afternoon or evening along some of the previously mentioned boundaries. For tonight, expect another cluster of thunderstorms to get organized to our west or northwest and move into our area overnight. Thunderstorms are already developing across the mountains of New Mexico, and upscale growth into a cluster of thunderstorms is expected as the shortwave moving into the area approaches. Several models indicate an MCS moving east through the Permian Basin overnight, and into our area by early tomorrow morning. Timing the arrival of these thunderstorms is difficult, but expect the bulk of the activity to be after midnight rather than before. Locally heavy rainfall, and dangerous lightning would be the primary concerns with these thunderstorms. Additional thunderstorm activity is possible tomorrow afternoon, especially if the atmosphere can destabilize during the afternoon hours. The favored area for redevelopment tomorrow appears to be northwest of the area near the Texas panhandle region where another approaching shortwave will interact with persistent moist upslope flow. Temperatures will remain near normal with lows near 70 tonight, highs around 90 tomorrow. 20 LONG TERM... (Tuesday night through next Monday) Weak northwest flow aloft will continue over our area Tuesday night and Wednesday. Could have a leftover disturbance (possibly a MCV) over our eastern counties Tuesday evening and early Tuesday night. The NAM brings a weak upper level disturbance southeast across the TX Panhandle and toward our far northern counties by early Wednesday morning. Showers and thunderstorms would be possible with both of these features. With this in mind, carrying 30 PoPs across our eastern and far northern counties Tuesday night, with 20 PoPs elsewhere. Have a lingering low PoP for the eastern part of our area on Wednesday, which will be on the eastern periphery of the upper level high. On Thursday and Friday, the upper high will remain positioned over Mexico and the U.S. Desert Southwest, with an eastward extension to near the Big Bend region. An upper shear axis is progged to set up to the east of our area. Cannot rule out a low possibility of showers/thunderstorms in some of our northern or eastern counties Thursday and Friday. However, with lack of confidence in placement of weak disturbances aloft or surface boundaries, prefer to leave PoPs out for now. For the weekend into the first part of next week, the 12Z GFS and ECMWF are in better agreement in gradually building the heights aloft over our area. While specific differences still exist, both models show an overall shift with the upper high to the north across the Southwestern states, while expanding it to the east into Texas and the Southern Plains. This would effectively shut off rain chances for our area, and lead to a warming trend in temperatures. However, with fairly moist ground conditions and evapotranspirative effects, along with south-southeasterly low- level flow keeping an influx of Gulf moisture into our area, believe the warming trend will be tempered. In addition, the GFS keeps the low-level thermal ridge to our west, with only a limited eastward expansion. With these indications, going with highs below the GFS MOS guidance for our area. 19 && .PRELIMINARY POINT TEMPS/POPS... Abilene 71 90 72 92 72 / 20 40 20 20 10 San Angelo 70 90 71 92 72 / 30 30 20 10 5 Junction 71 89 71 91 72 / 20 20 20 20 5 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 24
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
110 PM CDT SUN JUN 22 2014 .DISCUSSION... 18Z AVIATION DISCUSSION BELOW. && .AVIATION... REGIONAL ATMOSPHERE IS MOIST AND UNSTABLE ENOUGH TO SUPPORT WIDELY SCATTERED THUNDERSTORMS...ESPECIALLY NORTH AND EAST OF METRO TERMINALS. RECENT HIGH OVERCAST HAS LIMITED OVERALL CONVECTIVE COVERAGE...RETARDING HEATING INTO THE MID TO UPPER 80S. MID TO LATE AFTERNOON CLOUD BREAKS WILL ALLOW SFC TEMPERATURES TO HIT OR EXCEED 90F...INCREASING THE PROBABILITY FOR RETURNING -TSRA. DRY MID-LEVEL AIR WILL WIN OUT THROUGH MID TO LATE PERIOD ...MID TO HIGH LEVEL CLOUDINESS OVERNIGHT WITH PRECIPITATION PROBS BECOMING TO LOW TO MENTION VICINITY. 31 && .PREV DISCUSSION... /ISSUED 1030 AM CDT SUN JUN 22 2014/ UPDATE... SEE MORNING UPDATE. DISCUSSION... AT 9 AM...SFC HIGH PRESSURE WAS LOCATED OVER SW LOUISIANA AND LOW PRESSURE WAS OVER WESTERN KANSAS. VIS SATELLITE SHOWED EXTENSIVE CLOUD COVER OVER MOST OF THE STATE WITH SOME BREAKS IN THE CLOUDS OVER SE TX. 12Z SOUNDINGS SHOW PW VALUES AROUND 1.70 INCHES... CONVECTIVE TEMPS BETWEEN 86 AND 90 DEGREES...NO CAPPING AND WITH A LAYER OF DRY AIR BETWEEN 800 MB AND 600 MB. AT 850 MB...A SWATH OF DEEP MOISTURE EXTENDED ACROSS CENTRAL TEXAS EXTENDING FROM DODGE CITY KANSAS TO NORTHERN MEXICO. AN 850 MB RIDGE WAS OVER THE NORTHERN GULF AND EXTENDED NORTH INTO CENTRAL ARKANSAS. AT 700 MB...DEEPER MSTR AND A WEAK 700 MB TROUGH AXIS EXTENDED FROM NE TEXAS TO THE BIG BEND. AT 250 MB...A WEAK HIGH WAS OVER NORTHERN MEXICO WITH A SPEED MAX OVER NORTH CENTRAL MEXICO. A WEAK S/WV EXTENDED FROM SOUTH CENTRAL KANSAS TO NE TEXAS. BOTH THE ECMWF AND THE GFS SHOW SE TX IN A WEAK LFQ THIS AFTN AND THIS IS SUPPORTED BY THE 12Z 250 MB ANALYSIS. CONSIDERING THE LIFT PROVIDED BY THE SPEED MAX...A WEAK SPLIT IN THE UPPER JET... DIFFERENTIAL HEATING AND WEAK PVA...FEEL CONVECTIVE POTENTIAL WILL BE INCREASING THIS AFTN. THE RAP 13 AND HRRR SHOW THE BEST POTENTIAL OVER THE NE ZONES THIS AFTN SO HAVE RAISED POPS OVER THE NE. ANY STORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO PRODUCE HEAVY RAIN AS STORM MOTION WILL BE ON THE SLOW SIDE. CLOUDS WILL WREAK HAVOC WITH MAX TEMPS BUT ANY BREAK IN THE CLOUD COVER WILL ALLOW TEMPS TO WARM QUICKLY. LEFT TEMP FCST AS IS. OVERALL...ONLY MINOR CHANGES AS PREV FCST HAD THINGS WELL IN HAND. 43 && PREV DISCUSSION... /ISSUED 626 AM CDT SUN JUN 22 2014/ DISCUSSION... SEE AVIATION. AVIATION... SEEING A BAND OF SHRA APPROACHING NW AREAS OF SE TX THIS MORNING WHICH WILL AFFECT CLL 12-14Z. BY MID MORNING EXPECT TO SEE SCT SHRA ACROSS MOST OF THE AREA. EXPECT ISOLATED/SCATTERED TSRA AROUND THIS AFTERNOON...ESPECIALLY IN THE VICINITY OF A WEAK SEA BREEZE. AMPLE HIGH CLOUDS WILL CONTINUE THROUGH THE DAY. 33 && PREV DISCUSSION... /ISSUED 440 AM CDT SUN JUN 22 2014/ DISCUSSION... TX AREA RADAR SHOWS QUITE A BIT OF SHOWER ACTIVITY OVER N TX WHICH MAY BE THE RESULT OF A SHORTWAVE TROUGH AND OLD MCV THAT IS SHEARING OUT OVER THE AREA. CLOUD COVER HAS HELD TEMPS IN THE MID 70S FOR MUCH OF THE AREA THIS MORNING SO NOT QUITE AS COOL AS YESTERDAY. BASED ON 00Z SOUNDINGS LCH AND CRP ARE SHOWING PRECIP WATER VALUES OF 1.5 TO 1.7 INCHES RESPECTIVELY. THINK PRECIP WATER VALUES WILL BE CLOSER TO 1.7 INCHES OVER MUCH OF THE AREA TODAY. THE 00Z 500MB ANALYSIS SHOWS 589/590 DM HEIGHTS ALONG THE NW GULF COAST SO THINK RIDGE IS MOVING MORE INTO THE GULF TOWARDS THE BAY OF CAMPECHE. HEIGHTS HAVE COME DOWN SOME WHICH SHOULD SUPPORT MORE SHOWER AND THUNDERSTORM ACTIVITY TODAY ESPECIALLY WITH HIGHER MOISTURE. FORECAST WILL GO WITH MAINLY 30/40 POPS TODAY. LOOKING AT STORM TOTAL ACCUM RAINFALL FROM YESTERDAY...FEW STRONGER STORMS COULD EASILY DROP 1-2 INCHES OF RAIN IN A SHORT PERIOD OF TIME. MAIN IMPACT WILL BE LOCALIZED STREET FLOODING WITH THE HEAVY RAINFALL AND GUSTY WINDS FROM OUTFLOWS. BY MONDAY BROAD TROUGHING BECOMES MORE ESTABLISHED OVER TX AND REALLY NO HINT OF ANY RIDGING. MODELS OUTPUT MEAGER RAINFALL AMOUNTS AND KEEP POPS LOW SO WILL ONLY GO WITH 20/30 POPS. IT LOOKS LIKE PRECIP WATER VALUES MAY DROP CLOSER TO 1.5 INCHES ON MONDAY BEFORE SURGING BACK UP ON TUE/WED. TUE LOOK FOR HIGHER MOISTURE VALUES AND TROUGHING BECOMING MORE PRONOUNCED. SHORTWAVE NOW OVER CALIFORNIA WILL HAVE MADE ITS WAY ACROSS THE S ROCKIES INTO THE S PLAINS BY THIS TIME. THIS MAY HELP BRING HEIGHTS DOWN BELOW 588 DM AT 500MB. PRECIP WATER VALUES MAY BE APPROACHING 2 INCHES BY WED PER NAM/GFS SOLUTIONS. DECIDED TO GO A BIT HIGHER WITH POPS ON TUE INTO WED. WED LOOKS TO BE MORE WET BUT WILL KEEP POPS AT 50 FOR NOW. QUITE POSSIBLE TO HAVE SCATTERED TO WIDESPREAD CONVECTION EACH DAY FROM WEDNESDAY THROUGH THE END OF THE WEEK. BEST CHANCES OF RAIN LOOK TO BE WED/THUR/FRI WITH BROAD TROUGHING ALOFT AND PRECIP WATER VALUES NEAR 1.9 TO 2 INCHES EACH DAY. IT WILL NOT TAKE MUCH HEATING FOR CONVECTION TO DEVELOP EACH DAY. WITH THAT MUCH MOISTURE...MAIN CONCERN WILL BE LOCALLY HEAVY RAINFALL RESULTING IN LOCALIZED FLOODING. QUITE POSSIBLE THAT URBAN AREAS COULD SEE STREET FLOODING AS A RESULT. BAYOUS COULD RESPOND WITH RAPID RISES AS WELL. IMPACTS COULD BE MADE WORSE BY ANY TRAINING STORMS BUT TOO EARLY TO DETERMINE THOSE KINDS OF DETAILS JUST YET. OVERALL EXPECT TEMPERATURES TO BE IMPACTED BY CLOUD COVER AND CONVECTION. STILL SUMMER TIME SO IT DOES NOT TAKE MUCH TO REACH LOW 90S FOR MAX TEMPS. THIS ALSO MEANS CONVECTIVE TEMPS SHOULD BE REACHED AND TRIGGER CONVECTION. FORECAST WILL KEEP TEMPS IN THE 90-92F RANGE BUT COULD SEE UPPER 80S FOR HIGHS SHOULD SCATTERED TO WIDESPREAD CONVECTION DEVELOP. LOW TEMPS IN THE LOW/MID 70S LOOK ON TRACK AS WELL ESPECIALLY WITH ANY RAIN COOLED AIR THAT DEVELOPS. STILL NOT BAD HAVING TEMPS NEAR NORMAL FOR THE END OF JUNE. 39 && MARINE... PERSISTENT ONSHORE FLOW WILL CONTINUE THROUGH THE WEEK. SOUTHERLY WINDS WILL APPROACH SCEC CRITERIA WELL OFFSHORE TONIGHT AND MONDAY NIGHT...BUT WILL LIKELY STAY JUST BELOW. BY TUESDAY NIGHT THE PRESSURE GRADIENT TIGHTENS AND WE WILL LIKELY SEE 15 TO 20 KT ONSHORE WINDS OFFSHORE. BY MID-WEEK WINDS WILL INCREASE FURTHER AND SEAS WILL BUILD. BUMPED WINDS AND SEAS WED-FRI TO REFLECT THE CURRENT GFS...AND SCA CONDITIONS ARE POSSIBLE LATE THIS WEEK OFFSHORE. 33 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 75 91 76 90 74 / 20 20 20 40 20 HOUSTON (IAH) 76 92 77 90 75 / 20 20 20 40 20 GALVESTON (GLS) 80 88 80 87 80 / 10 20 20 30 40 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...43 AVIATION/MARINE...31
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1230 PM CDT SUN JUN 22 2014 .AVIATION... ISOLD SHRA/TSRA ARE POSSIBLE THIS AFTERNOON AND AGAIN ON MONDAY. HOWEVER...PROBS ARE TOO LOW TO MENTION IN THE TAFS. MVFR CIGS OVER THE HILL COUNTRY TO ALONG THE RIO GRANDE INCLUDING KDRT WILL RISE TO VFR BY 20Z. OTHERWISE...VFR SKIES WILL PREVAIL THIS AFTERNOON INTO EVENING. STRATUS WITH MVFR CIGS CAN BE EXPECTED TO DEVELOP BY AROUND 06Z...SPREADING TO ALL AREAS OVERNIGHT. PATCHY IFR CIGS ARE POSSIBLE OVER THE HIGHER HILL COUNTRY TERRAIN AND FOR AN HOUR OR TWO ELSEWHERE MONDAY MORNING. CIGS RISE TO VFR LATE MONDAY MORNING INTO THE AFTERNOON. S TO SE WINDS 10 TO 15 KTS WILL DECREASE TO 10 KTS OR LESS TONIGHT AND THEN INCREASE TO 10 TO 15 KTS MONDAY. OCNL GUSTS TO 22 KTS ARE POSSIBLE. && .PREV DISCUSSION... /ISSUED 643 AM CDT SUN JUN 22 2014/ AVIATION...ISOLATED TO SCATTERED LOW TOP SHOWERS MOVING E-NE ACROSS SOUTH CENTRAL TEXAS THIS MORNING. ANY OF THE TERMINAL SITES MIGHT SEE A PASSING SHOWER BUT IMPACTS WILL LIMITED TO MVFR CEILINGS BETWEEN 1500-2500 FEET. MULTI-LAYERED CLOUDS TO REMAIN ACROSS THE AREA WITH THE LOWER CLOUDS LIFTING AND BREAKING UP AROUND OR SHORTLY AFTER 16Z. ISOLATED SHOWERS AND THUNDERSTORMS TO REDEVELOP THIS AFTERNOON BUT CHANCE REMAINS LOW FOR ANY ONE TO PASS ACROSS TERMINALS SO WILL LEAVE OUT OF TAFS AT THIS TIME. LOW LEVEL INVERSION OVERNIGHT WITH MVFR CIGS EXPECTED TO RETURN ALONG THE I 35 CORRIDOR THEN SPREAD WEST. A LIGHT TO MODERATE PRESSURE GRADIENT TO MAINTAIN AND SOUTHEAST TO SOUTH FLOW AT SPEEDS UNDER 20 KNOTS. PREV DISCUSSION... /ISSUED 347 AM CDT SUN JUN 22 2014/ SHORT TERM (TODAY THROUGH MONDAY)... A WEAK SHEAR AXIS IS DRAPED ALONG AND NW OF I-35 EARLY THIS MORNING. LIGHT CONVECTION IS DEVELOPING ALONG THIS AXIS AND IS DEPICTED FAIRLY WELL BY THE RECENT RUC RUNS. THE SHEAR AXIS IS EXPECTED BY MODEL CONSENSUS TO SHIFT EAST AND POSSIBLY PUSH THE HIGHER RAIN CHANCES AND PWAT VALUES INTO EASTERN COUNTIES LATE TODAY WHILE MID LEVEL STABILITY BUILDS INTO WESTERN AND CENTRAL COUNTIES. THE INCREASING STABILITY IS SUGGESTED TO BE OVER A SHORT PERIOD... LASTING THROUGH LATE MONDAY. WITH REDUCED CLOUD COVER EXPECTED THE MILD AFTERNOON TEMPERATURES OF TODAY SHOULD REBOUND 2-4 DEGREES WARMER FOR MONDAY. LONG TERM (MONDAY NIGHT THROUGH SATURDAY)... A SMALL DISTURBANCE IS EXPECTED TO TRIGGER CONVECTION OVER THE SOUTHERN PLAINS LATE MONDAY AND POSSIBLY SEND A WEAKENING COMPLEX OF STORMS INTO THE AREA MONDAY NIGHT INTO TUESDAY. WITH NORTHERLY MID-LEVEL FLOW DEVELOPING DURING THIS PERIOD...SOME MODELS... ESPECIALLY THE CANADIAN...DEVELOP A LOW PRESSURE CENTER OVER CENTRAL TX AND AMPLIFY RAIN CHANCES INTO A POSSIBLE FLOOD PATTERN. A MORE CONSERVATIVE BLEND OF THE DRIER GFS AND WETTER ECMWF IS PREFERRED FOR FORECAST CONSISTENCY...BUT WILL NOTE THAT THE BROADER WEAKNESS OVER TX IS TYPICAL FOR JUNE HEAVY RAIN EVENTS. BASED ON MODEL CONSENSUS AN ENHANCEMENT OF DIURNAL THUNDERSTORM ACTIVITY IS PROBABLE FOR AREAS ALONG AND EAST OF I-35 WEDNESDAY THROUGH SATURDAY...AS EVEN THE DRIER GFS KEEPS A WEAK MID LEVEL SHEAR AXIS OVER CENTRAL TX THROUGH AS LATE AS THURSDAY. THE CONSENSUS OF WETTER AND DRIER MODEL SOLUTIONS IN THE EXTENDED FORECAST CONTINUES TO KEEP TEMPERATURES RELATIVELY MILD. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 90 74 92 74 90 / 30 10 10 20 20 AUSTIN BERGSTROM INTL AIRPORT 90 73 93 73 90 / 30 10 10 20 20 NEW BRAUNFELS MUNI AIRPORT 91 74 93 73 90 / 20 10 10 10 20 BURNET MUNI AIRPORT 87 72 91 72 88 / 20 - 20 20 20 DEL RIO INTL AIRPORT 91 74 96 75 94 / 10 - 10 10 10 GEORGETOWN MUNI AIRPORT 89 73 92 73 90 / 20 10 20 20 20 HONDO MUNI AIRPORT 92 73 93 73 93 / 20 10 10 10 20 SAN MARCOS MUNI AIRPORT 90 74 92 73 90 / 20 10 10 20 20 LA GRANGE - FAYETTE REGIONAL 91 76 93 75 90 / 30 10 20 20 30 SAN ANTONIO INTL AIRPORT 90 76 93 75 90 / 20 10 10 10 20 STINSON MUNI AIRPORT 92 75 94 75 92 / 20 10 10 10 20 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...04 SYNOPTIC/GRIDS...25 PUBLIC SERVICE/DATA COLLECTION...32
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1030 AM CDT SUN JUN 22 2014 .UPDATE... SEE MORNING UPDATE. && .DISCUSSION... AT 9 AM...SFC HIGH PRESSURE WAS LOCATED OVER SW LOUISIANA AND LOW PRESSURE WAS OVER WESTERN KANSAS. VIS SATELLITE SHOWED EXTENSIVE CLOUD COVER OVER MOST OF THE STATE WITH SOME BREAKS IN THE CLOUDS OVER SE TX. 12Z SOUNDINGS SHOW PW VALUES AROUND 1.70 INCHES... CONVECTIVE TEMPS BETWEEN 86 AND 90 DEGREES...NO CAPPING AND WITH A LAYER OF DRY AIR BETWEEN 800 MB AND 600 MB. AT 850 MB...A SWATH OF DEEP MOISTURE EXTENDED ACROSS CENTRAL TEXAS EXTENDING FROM DODGE CITY KANSAS TO NORTHERN MEXICO. AN 850 MB RIDGE WAS OVER THE NORTHERN GULF AND EXTENDED NORTH INTO CENTRAL ARKANSAS. AT 700 MB...DEEPER MSTR AND A WEAK 700 MB TROUGH AXIS EXTENDED FROM NE TEXAS TO THE BIG BEND. AT 250 MB...A WEAK HIGH WAS OVER NORTHERN MEXICO WITH A SPEED MAX OVER NORTH CENTRAL MEXICO. A WEAK S/WV EXTENDED FROM SOUTH CENTRAL KANSAS TO NE TEXAS. BOTH THE ECMWF AND THE GFS SHOW SE TX IN A WEAK LFQ THIS AFTN AND THIS IS SUPPORTED BY THE 12Z 250 MB ANALYSIS. CONSIDERING THE LIFT PROVIDED BY THE SPEED MAX...A WEAK SPLIT IN THE UPPER JET... DIFFERENTIAL HEATING AND WEAK PVA...FEEL CONVECTIVE POTENTIAL WILL BE INCREASING THIS AFTN. THE RAP 13 AND HRRR SHOW THE BEST POTENTIAL OVER THE NE ZONES THIS AFTN SO HAVE RAISED POPS OVER THE NE. ANY STORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO PRODUCE HEAVY RAIN AS STORM MOTION WILL BE ON THE SLOW SIDE. CLOUDS WILL WREAK HAVOC WITH MAX TEMPS BUT ANY BREAK IN THE CLOUD COVER WILL ALLOW TEMPS TO WARM QUICKLY. LEFT TEMP FCST AS IS. OVERALL...ONLY MINOR CHANGES AS PREV FCST HAD THINGS WELL IN HAND. 43 && .PREV DISCUSSION... /ISSUED 626 AM CDT SUN JUN 22 2014/ DISCUSSION... SEE AVIATION. AVIATION... SEEING A BAND OF SHRA APPROACHING NW AREAS OF SE TX THIS MORNING WHICH WILL AFFECT CLL 12-14Z. BY MID MORNING EXPECT TO SEE SCT SHRA ACROSS MOST OF THE AREA. EXPECT ISOLATED/SCATTERED TSRA AROUND THIS AFTERNOON...ESPECIALLY IN THE VICINITY OF A WEAK SEA BREEZE. AMPLE HIGH CLOUDS WILL CONTINUE THROUGH THE DAY. 33 PREV DISCUSSION... /ISSUED 440 AM CDT SUN JUN 22 2014/ DISCUSSION... TX AREA RADAR SHOWS QUITE A BIT OF SHOWER ACTIVITY OVER N TX WHICH MAY BE THE RESULT OF A SHORTWAVE TROUGH AND OLD MCV THAT IS SHEARING OUT OVER THE AREA. CLOUD COVER HAS HELD TEMPS IN THE MID 70S FOR MUCH OF THE AREA THIS MORNING SO NOT QUITE AS COOL AS YESTERDAY. BASED ON 00Z SOUNDINGS LCH AND CRP ARE SHOWING PRECIP WATER VALUES OF 1.5 TO 1.7 INCHES RESPECTIVELY. THINK PRECIP WATER VALUES WILL BE CLOSER TO 1.7 INCHES OVER MUCH OF THE AREA TODAY. THE 00Z 500MB ANALYSIS SHOWS 589/590 DM HEIGHTS ALONG THE NW GULF COAST SO THINK RIDGE IS MOVING MORE INTO THE GULF TOWARDS THE BAY OF CAMPECHE. HEIGHTS HAVE COME DOWN SOME WHICH SHOULD SUPPORT MORE SHOWER AND THUNDERSTORM ACTIVITY TODAY ESPECIALLY WITH HIGHER MOISTURE. FORECAST WILL GO WITH MAINLY 30/40 POPS TODAY. LOOKING AT STORM TOTAL ACCUM RAINFALL FROM YESTERDAY...FEW STRONGER STORMS COULD EASILY DROP 1-2 INCHES OF RAIN IN A SHORT PERIOD OF TIME. MAIN IMPACT WILL BE LOCALIZED STREET FLOODING WITH THE HEAVY RAINFALL AND GUSTY WINDS FROM OUTFLOWS. BY MONDAY BROAD TROUGHING BECOMES MORE ESTABLISHED OVER TX AND REALLY NO HINT OF ANY RIDGING. MODELS OUTPUT MEAGER RAINFALL AMOUNTS AND KEEP POPS LOW SO WILL ONLY GO WITH 20/30 POPS. IT LOOKS LIKE PRECIP WATER VALUES MAY DROP CLOSER TO 1.5 INCHES ON MONDAY BEFORE SURGING BACK UP ON TUE/WED. TUE LOOK FOR HIGHER MOISTURE VALUES AND TROUGHING BECOMING MORE PRONOUNCED. SHORTWAVE NOW OVER CALIFORNIA WILL HAVE MADE ITS WAY ACROSS THE S ROCKIES INTO THE S PLAINS BY THIS TIME. THIS MAY HELP BRING HEIGHTS DOWN BELOW 588 DM AT 500MB. PRECIP WATER VALUES MAY BE APPROACHING 2 INCHES BY WED PER NAM/GFS SOLUTIONS. DECIDED TO GO A BIT HIGHER WITH POPS ON TUE INTO WED. WED LOOKS TO BE MORE WET BUT WILL KEEP POPS AT 50 FOR NOW. QUITE POSSIBLE TO HAVE SCATTERED TO WIDESPREAD CONVECTION EACH DAY FROM WEDNESDAY THROUGH THE END OF THE WEEK. BEST CHANCES OF RAIN LOOK TO BE WED/THUR/FRI WITH BROAD TROUGHING ALOFT AND PRECIP WATER VALUES NEAR 1.9 TO 2 INCHES EACH DAY. IT WILL NOT TAKE MUCH HEATING FOR CONVECTION TO DEVELOP EACH DAY. WITH THAT MUCH MOISTURE...MAIN CONCERN WILL BE LOCALLY HEAVY RAINFALL RESULTING IN LOCALIZED FLOODING. QUITE POSSIBLE THAT URBAN AREAS COULD SEE STREET FLOODING AS A RESULT. BAYOUS COULD RESPOND WITH RAPID RISES AS WELL. IMPACTS COULD BE MADE WORSE BY ANY TRAINING STORMS BUT TOO EARLY TO DETERMINE THOSE KINDS OF DETAILS JUST YET. OVERALL EXPECT TEMPERATURES TO BE IMPACTED BY CLOUD COVER AND CONVECTION. STILL SUMMER TIME SO IT DOES NOT TAKE MUCH TO REACH LOW 90S FOR MAX TEMPS. THIS ALSO MEANS CONVECTIVE TEMPS SHOULD BE REACHED AND TRIGGER CONVECTION. FORECAST WILL KEEP TEMPS IN THE 90-92F RANGE BUT COULD SEE UPPER 80S FOR HIGHS SHOULD SCATTERED TO WIDESPREAD CONVECTION DEVELOP. LOW TEMPS IN THE LOW/MID 70S LOOK ON TRACK AS WELL ESPECIALLY WITH ANY RAIN COOLED AIR THAT DEVELOPS. STILL NOT BAD HAVING TEMPS NEAR NORMAL FOR THE END OF JUNE. 39 MARINE... PERSISTENT ONSHORE FLOW WILL CONTINUE THROUGH THE WEEK. SOUTHERLY WINDS WILL APPROACH SCEC CRITERIA WELL OFFSHORE TONIGHT AND MONDAY NIGHT...BUT WILL LIKELY STAY JUST BELOW. BY TUESDAY NIGHT THE PRESSURE GRADIENT TIGHTENS AND WE WILL LIKELY SEE 15 TO 20 KT ONSHORE WINDS OFFSHORE. BY MID-WEEK WINDS WILL INCREASE FURTHER AND SEAS WILL BUILD. BUMPED WINDS AND SEAS WED-FRI TO REFLECT THE CURRENT GFS...AND SCA CONDITIONS ARE POSSIBLE LATE THIS WEEK OFFSHORE. 33 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 90 75 91 76 90 / 40 20 20 20 40 HOUSTON (IAH) 90 76 92 77 90 / 40 20 20 20 40 GALVESTON (GLS) 87 80 88 80 87 / 20 10 20 20 30 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...43
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
643 AM CDT SUN JUN 22 2014 .AVIATION...ISOLATED TO SCATTERED LOW TOP SHOWERS MOVING E-NE ACROSS SOUTH CENTRAL TEXAS THIS MORNING. ANY OF THE TERMINAL SITES MIGHT SEE A PASSING SHOWER BUT IMPACTS WILL LIMITED TO MVFR CEILINGS BETWEEN 1500-2500 FEET. MULTI-LAYERED CLOUDS TO REMAIN ACROSS THE AREA WITH THE LOWER CLOUDS LIFTING AND BREAKING UP AROUND OR SHORTLY AFTER 16Z. ISOLATED SHOWERS AND THUNDERSTORMS TO REDEVELOP THIS AFTERNOON BUT CHANCE REMAINS LOW FOR ANY ONE TO PASS ACROSS TERMINALS SO WILL LEAVE OUT OF TAFS AT THIS TIME. LOW LEVEL INVERSION OVERNIGHT WITH MVFR CIGS EXPECTED TO RETURN ALONG THE I 35 CORRIDOR THEN SPREAD WEST. A LIGHT TO MODERATE PRESSURE GRADIENT TO MAINTAIN AND SOUTHEAST TO SOUTH FLOW AT SPEEDS UNDER 20 KNOTS. && .PREV DISCUSSION... /ISSUED 347 AM CDT SUN JUN 22 2014/ SHORT TERM (TODAY THROUGH MONDAY)... A WEAK SHEAR AXIS IS DRAPED ALONG AND NW OF I-35 EARLY THIS MORNING. LIGHT CONVECTION IS DEVELOPING ALONG THIS AXIS AND IS DEPICTED FAIRLY WELL BY THE RECENT RUC RUNS. THE SHEAR AXIS IS EXPECTED BY MODEL CONSENSUS TO SHIFT EAST AND POSSIBLY PUSH THE HIGHER RAIN CHANCES AND PWAT VALUES INTO EASTERN COUNTIES LATE TODAY WHILE MID LEVEL STABILITY BUILDS INTO WESTERN AND CENTRAL COUNTIES. THE INCREASING STABILITY IS SUGGESTED TO BE OVER A SHORT PERIOD... LASTING THROUGH LATE MONDAY. WITH REDUCED CLOUD COVER EXPECTED THE MILD AFTERNOON TEMPERATURES OF TODAY SHOULD REBOUND 2-4 DEGREES WARMER FOR MONDAY. LONG TERM (MONDAY NIGHT THROUGH SATURDAY)... A SMALL DISTURBANCE IS EXPECTED TO TRIGGER CONVECTION OVER THE SOUTHERN PLAINS LATE MONDAY AND POSSIBLY SEND A WEAKENING COMPLEX OF STORMS INTO THE AREA MONDAY NIGHT INTO TUESDAY. WITH NORTHERLY MID-LEVEL FLOW DEVELOPING DURING THIS PERIOD...SOME MODELS... ESPECIALLY THE CANADIAN...DEVELOP A LOW PRESSURE CENTER OVER CENTRAL TX AND AMPLIFY RAIN CHANCES INTO A POSSIBLE FLOOD PATTERN. A MORE CONSERVATIVE BLEND OF THE DRIER GFS AND WETTER ECMWF IS PREFERRED FOR FORECAST CONSISTENCY...BUT WILL NOTE THAT THE BROADER WEAKNESS OVER TX IS TYPICAL FOR JUNE HEAVY RAIN EVENTS. BASED ON MODEL CONSENSUS AN ENHANCEMENT OF DIURNAL THUNDERSTORM ACTIVITY IS PROBABLE FOR AREAS ALONG AND EAST OF I-35 WEDNESDAY THROUGH SATURDAY...AS EVEN THE DRIER GFS KEEPS A WEAK MID LEVEL SHEAR AXIS OVER CENTRAL TX THROUGH AS LATE AS THURSDAY. THE CONSENSUS OF WETTER AND DRIER MODEL SOLUTIONS IN THE EXTENDED FORECAST CONTINUES TO KEEP TEMPERATURES RELATIVELY MILD. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 90 74 92 74 90 / 30 10 10 20 20 AUSTIN BERGSTROM INTL AIRPORT 90 73 93 73 90 / 30 10 10 20 20 NEW BRAUNFELS MUNI AIRPORT 91 74 93 73 90 / 20 10 10 10 20 BURNET MUNI AIRPORT 87 72 91 72 88 / 20 - 20 20 20 DEL RIO INTL AIRPORT 91 74 96 75 94 / 10 - 10 10 10 GEORGETOWN MUNI AIRPORT 89 73 92 73 90 / 20 10 20 20 20 HONDO MUNI AIRPORT 92 73 93 73 93 / 20 10 10 10 20 SAN MARCOS MUNI AIRPORT 90 74 92 73 90 / 20 10 10 20 20 LA GRANGE - FAYETTE REGIONAL 91 76 93 75 90 / 30 10 20 20 30 SAN ANTONIO INTL AIRPORT 90 76 93 75 90 / 20 10 10 10 20 STINSON MUNI AIRPORT 92 75 94 75 92 / 20 10 10 10 20 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...99 SYNOPTIC/GRIDS...18
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
347 AM CDT SUN JUN 22 2014 .SHORT TERM (TODAY THROUGH MONDAY)... A WEAK SHEAR AXIS IS DRAPED ALONG AND NW OF I-35 EARLY THIS MORNING. LIGHT CONVECTION IS DEVELOPING ALONG THIS AXIS AND IS DEPICTED FAIRLY WELL BY THE RECENT RUC RUNS. THE SHEAR AXIS IS EXPECTED BY MODEL CONSENSUS TO SHIFT EAST AND POSSIBLY PUSH THE HIGHER RAIN CHANCES AND PWAT VALUES INTO EASTERN COUNTIES LATE TODAY WHILE MID LEVEL STABILITY BUILDS INTO WESTERN AND CENTRAL COUNTIES. THE INCREASING STABILITY IS SUGGESTED TO BE OVER A SHORT PERIOD... LASTING THROUGH LATE MONDAY. WITH REDUCED CLOUD COVER EXPECTED THE MILD AFTERNOON TEMPERATURES OF TODAY SHOULD REBOUND 2-4 DEGREES WARMER FOR MONDAY. && .LONG TERM (MONDAY NIGHT THROUGH SATURDAY)... A SMALL DISTURBANCE IS EXPECTED TO TRIGGER CONVECTION OVER THE SOUTHERN PLAINS LATE MONDAY AND POSSIBLY SEND A WEAKENING COMPLEX OF STORMS INTO THE AREA MONDAY NIGHT INTO TUESDAY. WITH NORTHERLY MID-LEVEL FLOW DEVELOPING DURING THIS PERIOD...SOME MODELS... ESPECIALLY THE CANADIAN...DEVELOP A LOW PRESSURE CENTER OVER CENTRAL TX AND AMPLIFY RAIN CHANCES INTO A POSSIBLE FLOOD PATTERN. A MORE CONSERVATIVE BLEND OF THE DRIER GFS AND WETTER ECMWF IS PREFERRED FOR FORECAST CONSISTENCY...BUT WILL NOTE THAT THE BROADER WEAKNESS OVER TX IS TYPICAL FOR JUNE HEAVY RAIN EVENTS. BASED ON MODEL CONSENSUS AN ENHANCEMENT OF DIURNAL THUNDERSTORM ACTIVITY IS PROBABLE FOR AREAS ALONG AND EAST OF I-35 WEDNESDAY THROUGH SATURDAY...AS EVEN THE DRIER GFS KEEPS A WEAK MID LEVEL SHEAR AXIS OVER CENTRAL TX THROUGH AS LATE AS THURSDAY. THE CONSENSUS OF WETTER AND DRIER MODEL SOLUTIONS IN THE EXTENDED FORECAST CONTINUES TO KEEP TEMPERATURES RELATIVELY MILD. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 90 74 92 74 90 / 30 10 10 20 20 AUSTIN BERGSTROM INTL AIRPORT 90 73 93 73 90 / 30 10 10 20 20 NEW BRAUNFELS MUNI AIRPORT 91 74 93 73 90 / 20 10 10 10 20 BURNET MUNI AIRPORT 87 72 91 72 88 / 20 - 20 20 20 DEL RIO INTL AIRPORT 91 74 96 75 94 / 10 - 10 10 10 GEORGETOWN MUNI AIRPORT 89 73 92 73 90 / 20 10 20 20 20 HONDO MUNI AIRPORT 92 73 93 73 93 / 20 10 10 10 20 SAN MARCOS MUNI AIRPORT 90 74 92 73 90 / 20 10 10 20 20 LA GRANGE - FAYETTE REGIONAL 91 76 93 75 90 / 30 10 20 20 30 SAN ANTONIO INTL AIRPORT 90 76 93 75 90 / 20 10 10 10 20 STINSON MUNI AIRPORT 92 75 94 75 92 / 20 10 10 10 20 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...99 SYNOPTIC/GRIDS...18
AREA FORECAST DISCUSSION
NWS MIDLAND/ODESSA TX
1237 AM CDT Sun Jun 22 2014 .AVIATION... 06Z TAF issuance... The main aviation concern for the next 24 hours is MVFR cigs affecting CNM, HOB and MAF late tonight through early morning. Have low stratus developing at HOB and MAF by 22/09Z then improving conditions around 22/13-14Z. Think the stratus will approach CNM from the east but not quite sure it will make it. Went ahead and kept TEMPO from 13-15Z for now. Will need to amend or add low cigs at other sites if MVFR develops there. Otherwise, VFR conditions are expected to prevail late morning through the end of this TAF cycle. && PREV DISCUSSION... /ISSUED 212 PM CDT Sat Jun 21 2014/ DISCUSSION... A well defined Mexican moisture tap is still evident on water vapor imagery with embedded shrtwv trof/s, one of which is lifting out the area while another model depicted shrtwv trof follows and in part is responsible for renewed SHRA/TSRA. The area where SHRA/TSRA have been occurring is area co-located where 9h-85h mstr flux has persisted and PWs are near 1.75" per GEFS (about 2.5 standard deviations above normal). The RUC13 show this area of moisture flux redeveloping to the n into the n-ne PB and thus we would not be surprised to SHRA/TSRA develop into the n-ne these next few hrs. Heavy rain is main concern and local flooding/flash flooding is possible. Mid level ridge will slowly builds in from the w and serve to push the general mid level trof/moisture axis that has been over the area to the e resulting in a decreased chance of rain and an increase in temperatures. Still there are some opportunities for precip. For Sunday PoPs will generally be confined to the mtns where very steep LR/s of 8-9 c/km are to be coincident with sfc dwpnts in the m40-50 along e slopes, flow will be upslope, and CINH will be a non-issue in/near elevated heat sources. Meanwhile Sunday night storms may near the far NW CWFA with shrtwv trof in NW flow aloft. On Monday NAM12/ECMWF better depicts a shrtwv trof in the NW flow and develops storms by mid/late afternoon in E-SE NM and then in PB after 21Z. Development may be enhanced by a boundary from previous convection and/or its own cold pool. Timing will be important, if it does come thru early then there won`t be much concern for precip into the evening. Tue models hint at tstms from the mtns into E-SE NM where moist se low level flow and secondary mid level theta-e ridge are expected to be. ECMWF wants light up the mtns again Thur/Fri, while the GFS confines precip moreso to the Davis mtns. As frequently is the case for the mtns the development is tied to the mid level theta-e ridge axis and based on consensus of data the Davis mtns are favored over the GDP mtns. A mid level trof is progged to push in to the n Friday, which may advect drier air ewd. Through the extended part of the fcst the GFS is much warmer than ECMWF in part due to its more veered/stronger wly winds which aids thermal ridge/dry air. Climatology certainly favors the GFS and with warm temperatures already in forecast with probably use a blender approach to catch general trends. && .MAF WATCHES/WARNINGS/ADVISORIES... NM...NONE. TX...NONE. && $$ 27
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
926 PM EDT MON JUN 23 2014 .SYNOPSIS... A WEAK AREA OF HIGH PRESSURE OFF THE COAST OF NEW ENGLAND WILL DRIFT EAST DURING THE NEXT COUPLE OF DAYS AS LOW PRESSURE ADVANCES SLOWLY FROM OUT OF THE MIDWEST. SOUTHERLY FLOW BETWEEN THE SYSTEMS WILL PULL IN INCREASINGLY MOIST AIR BACK INTO THE MID APPALACHIAN AND MID ATLANTIC REGION INTO MID WEEK...MAINTAINING A DAILY THREAT FOR SHOWERS AND THUNDERSTORMS. && .NEAR TERM /THROUGH TUESDAY/... AS OF 845 PM EDT MONDAY... CONVECTION HAS BEEN LACKING FOR A CHANGE THIS EVENING AS THE COMBO OF THE RESIDUAL WEAK WEDGE...LACK OF UPPER FORCING AND ONLY WEAK INSTABILITY CONTINUES TO KEEP SHOWERS LIMITED TO THE EXTREME WEST/SW. THIS IN AN AREA OF RETURN SE FLOW AS BETTER LIFT REMAINS WELL TO THE WEST AHEAD OF THE NEXT FRONT. LATEST HRRR TRIES TO SNEAK A FEW SHRA/TSRA IN FROM THE SOUTH ACROSS NW NC/SW VA IN THE NEXT FEW HOURS AND ALONG THE SOUTHERN BLUE AFTER MIDNIGHT. HOWEVER THIS LOOKS IFFY GIVEN CURRENT TRENDS...SO HAVE ALREADY REMOVED MOST POPS EARLY THIS EVENING...BUT WILL KEEP IN CHANCE POPS SW OVERNIGHT ESPCLY THE NW N CAROLINA MOUNTAINS/FOOTHILLS PER DEEPER UPSLOPE FLOW AND LINGERING WEAK INSTABILITY. DO EXPECT THE WEDGE TO FLOP BACK TO THE WEST WITH CURRENT STRATO- CU ALONG THE BLUE RIDGE LIKELY TO LOWER AND EXPAND FURTHER AFTER MIDNIGHT UNDER A WEAK BUT MORE EASTERLY TRAJECTORY. ALSO SOME FOG AROUND BUT GIVEN LIGHT MIXING EARLY AND CLOUDS APPEARS ONLY PATCHY COVERAGE FOR THE MOST PART. LOW TEMPS ON TRACK WITH SOME SLIGHT DOWNWARD ADJUSTS IN THE VALLEYS...OTRW MOSTLY LOW/MID 60S LOOK GOOD. THE WEDGE SHOULD BE EAST OF THE AREA TUESDAY MORNING WITH A COLD FRONT AND ASSOCIATED SURFACE LOW OVER THE UPPER MISSISSIPPI VALLEY. THIS WILL PLACE THE AREA IN A WARM AND HUMID AIRMASS WITH PULSE STORMS SLOWLY TRACKING SOUTHWEST TO NORTHEAST STARTING IN THE MOUNTAINS BY LATE AFTERNOON AND EAST OF THE BLUE RIDGE BY MID AFTERNOON. INSTABILITIES WILL BE GREATER TOMORROW THEREFORE THE CHANCE FOR SEEING MORE STRONGER STORMS DEVELOPING COMPARED TO TODAY ARE GOOD. PWAT VALUES WILL ALSO INCREASE TOMORROW BUT HOVERING AROUND NORMAL FOR THIS TIME OF YEAR. WIDESPREAD FLASH FLOOD THREAT IS LOW WHILE LOCALIZED FLOODING IS ALWAYS POSSIBLE. TEMPERATURES WILL ALSO BE NEAR NORMAL TUESDAY. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... AS OF 305 PM EDT MONDAY... ACTIVE PATTERN THROUGH WEDNESDAY EVENING...AS TROUGH AND ASSOCIATED SFC FRONT EDGE EAST INTO THE MTNS BY 18Z WED THEN SLOW DOWN AS IT ENCOUNTERS THE WRN ATLANTIC RIDGE. MODELS FAVOR EXITING THE SHORTWAVE AFTER MIDNIGHT WED NIGHT...THEN MODELS STILL BRING WEAK ENERGY INTO THE CENTRAL APPALACHIANS THURSDAY...WHILE FRONT STALLS OVER THE ERN VA/NC AREA. THINK THURSDAY WILL BE DRIER FOR MOST...BUT COULD SEE ENOUGH LINGERING MOISTURE AROUND AND WITH SOME CONVERGENCE IN THE LOW LVLS AT LEAST ISOLATED CONVECTION POSSIBLE. ATTM...WEDNESDAY WILL BE WETTER/STORMIER WITH 40-60 POPS...HIGHER IN THE NW CLOSER TO THE UPPER SUPPORT. THE STORM PREDICTION CENTER IS NOT HIGHLIGHTING ANY SVR THREAT. TIMING OF CLOUDS/STORMS MAY OFFSET LOW LVL INSTABILITY/LAPSE RATES...BUT CANNOT RULE OUT SOME ISOLATED SVR THREAT. TEMPS REMAIN TYPICAL OF LATE JUNE. BEHIND THE FRONT THURSDAY HUMIDITY LEVELS MAY SINK SOME...WITH DEWPOINTS DROPPING FROM THE MID 60S WEST TO UPPER 50S/LOWER 60S. THE EAST WILL STAY SOMEWHAT ELEVATED AS FRONTAL BOUNDARY LINGERS JUST EAST OF THE FORECAST AREA. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 155 PM EDT MONDAY... GOING TO SEE TYPICAL SUMMER PATTERN IN THE REGION THIS PERIOD. MOISTURE REMAINS ELEVATED IN THE LOW LVLS WITH WEAK WAVES ALOFT HARD TO PINPOINT EARLY ON TIMING WISE. RIDGE BUILDS INTO THE WEEKEND AND EARLY NEXT WEEK SUCH THAT THREAT OF STORMS WILL BE MAINLY IN THE AFTERNOON/EVENINGS. HOWEVER...CANNOT RULE OUT OVERNIGHT SHOWERS OR STORM THREAT GIVEN THE SW FLOW ALOFT AND LOW LVL MOISTURE CONVERGENCE. FRONTAL BOUNDARY EXISTS EARLY IN THE PERIOD FROM THE OHIO VALLEY INTO THE SOUTHEAST BUT WIND FIELDS ARE WEAK. STILL WILL SEE AT LEAST THE POPS IN THE 30-50 RANGE FOR FRI-SAT. TEMPS STAY ABOVE NORMAL AT NIGHT DUE TO THE MOISTURE CONTENT IN THE ATMOSPHERE...WHILE DAYTIME HIGHS STAY CLOSER TO WHAT WE EXPECT FOR LATE JUNE...WITH UPPER 70S HIGHER TERRAIN...LOWER TO MID 80S REST OF THE MOUNTAINS...AND MID 80S/NEAR 90 SOUTHEAST. && .AVIATION /01Z TUESDAY THROUGH SATURDAY/... AS OF 650 PM EDT MONDAY... LINGERING LOW LEVEL WEDGE OVER THE EAST UNDER HIGH PRESSURE NOSING IN FROM THE NE HAS BASICALLY PUT A LID ON MOST CONVECTION THIS EVENING WITH ANY SHRA/TSRA ACROSS THE FAR SW MAINLY WEST OF KBLF. SOME OF THIS ISOLATED COVERAGE ON THE WESTERN PERIMETER OF THE WEDGE MAY SNEAK FAR ENOUGH EAST TO REACH THE KBLF VICINITY BEFORE LOSS OF HEATING...OTRW APPEARS NOT ENOUGH INSTABILITY OR FORCING FOR SHOWERS ATTM. OTHER CONCERN WITH THE REDEVELOPMENT OF THE WEDGE FROM THE EAST AFTER SUNSET WITH GUIDANCE AGAIN SHOWING WIDESPREAD IFR/LIFR CIGS AND MVFR VSBYS IN STRATUS/FOG FROM THE BLUE RIDGE EAST BY MORNING. SINCE CONSENSUS PER THE RAPID REFRESH ENSEMBLE SYSTEM SHOWS ANY LOWER CIGS OR VSBYS NOT OCCURRING UNTIL AFTER MIDNIGHT DELAYED THE ONSET OF MVFR CIGS THIS EVENING. HOWEVER INCLUDED SOME MVFR CIGS MAINLY KROA EAST BY MORNING WHILE TEMPOING IN LOWER IFR CONDITIONS FOR A FEW HOURS LATE ACROSS THE EAST AS THE WEDGE DEEPENS A BIT LATE. CLEARING IN THE WEST MAY ALSO PROMPT FOG DEVELOPMENT AT KLWB/KBCB WHERE COULD SEE A BRIEF PERIOD OF IFR/LIFR PENDING CLOUDS WHILE APPEARS KBLF MAY STAY VFR FOR THE MOST PART. WEDGE WEAKENS AGAIN ON TUESDAY AHEAD OF THE NEXT TROUGH TO THE WEST ALLOWING A SOMEWHAT DEEPER SOUTHERLY TRAJECTORY TO TAKE SHAPE DURING THE AFTERNOON AS HIGH PRESSURE PUSHES OFFSHORE. THIS SHOULD MAKE FOR MAINLY BKN VFR CU CIGS BY MIDDAY ONCE EARLY FOG/STRATUS FADE BUT LOW CONFIDENCE IN TIMING OF LOW CLOUD EXODUS AS WELL AS ADDED CONVECTIVE CHANCES LATER IN THE DAY. LATEST MODELS SHOW MOST SHRA/TSRA STILL WEST OF THE REGION DESPITE THE WEAKENING UPPER RIDGE BUT APPEARS ENOUGH INSTABILITY TO INCLUDE A VICINITY MENTION AT KBLF/KLWB FOR NOW. EXTENDED AVIATION DISCUSSION... NEXT UPPER TROUGH AND ITS ASSOCIATED COLD FRONT WILL APPROACH FROM THE WEST TUESDAY NIGHT INTO WEDNESDAY...WITH AN INCREASING THREAT FOR MORE WIDESPREAD SHOWERS AND STORMS WEDNESDAY AFTERNOON/EVENING. TIMING REMAINS A BIT IN QUESTION AS POTENTIAL EARLIER ARRIVAL COULD MEAN MORE COVERAGE IN THE EAST INCLUDING PERIODS OF MVFR/IFR IN STRONGER STORMS...WHILE BETTER CHANCE OF MORE WIDESPREAD LOWER CONDITIONS ACROSS THE ENTIRE REGION IF THE FRONT SLOWS. MAY SEE SOME IMPROVEMENT ON THURSDAY AS THE FRONT WASHES OUT OVERHEAD OR PUSHES TO THE SE...BUT STILL ENOUGH MOISTURE WITH HEATING FOR ADDED DIURNAL CONVECTION AGAIN THURSDAY AFTERNOON WITH PERIODS OF MVFR POSSIBLE. MOISTURE LIKELY RETURNS ON FRIDAY WITH A REPEAT OF MAINLY AFTERNOON/EVENING CONVECTION FRIDAY LEADING TO BRIEF PERIODS OF MVFR/IFR. THIS TREND LOOKS TO PERSIST AGAIN ON SATURDAY WITH AT LEAST ISOLATED CONVECTION MAKING FOR OCNL MVFR/IFR IN SPOTS SATURDAY AFTERNOON AND EVENING. OTRW AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE NIGHT/EARLY MORNING...PARTICULARLY IN AREAS THAT SEE RAIN THE PREVIOUS AFTERNOON. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...WERT/WP NEAR TERM...JH/RCS SHORT TERM...WP LONG TERM...WP AVIATION...JH/RCS/WERT
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
107 PM EDT SUN JUN 22 2014 .SYNOPSIS... WEDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA TODAY AND TONIGHT. MOISTURE WILL RETURN AGAIN BY MONDAY...RESULTING IN A DAILY THREAT SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY. A COLD FRONT WILL APPROACH FROM THE NORTHWEST BY THE MIDDLE OF THE WEEK...BRINGING IN MORE WIDESPREAD SHOWERS AND STORMS. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 202 PM EDT SUNDAY... A WEDGE REMAINS IN PLACE ACROSS THE PIEDMONT WITH ABUNDANT LOW CLOUDS AND NORTHEASTERLY FLOW. ACROSS THE MOUNTAINS...LOW LEVEL FLOW IS WESTERLY WITH LESS CLOUDS AND MORE SUNSHINE. THE CONVERGENCE OF THESE WIND FLOWS IS ALONG THE BLUE RIDGE AND FOOTHILL COUNTIES. ACROSS THE NORTHERN NORTH CAROLINA FOOTHILLS...CAPE VALUES ARE AROUND 800 J/KG AND OVER THE MOUNTAINS AROUND 500 J/KG. HIRES MODELS DISPLAYING TWO SCENARIOS. ONE IS TO HAVE SHOWERS DEVELOP IN THE CONVERGENCE ZONE DURING THE AFTERNOON. AS THESE STORMS GET TALLER...STEERING FLOW WILL HAVE THEM DRIFT TO THE EAST INTO THIS EVENING. THE SECOND SCENARIO IS TO HAVE SCATTERED CONVECTION OVER THE OHIO VALLEY TRACK INTO THE NORTH THIS AFTERNOON...THEN TAP HEAT AND MOISTURE AND BLOWUP MOVING EAST ALONG THE WEDGE BOUNDARY. BOTH ARE VIABLE SOLUTIONS AND ARE DEPICTING IN THE FORECAST GRIDS FROM A BLEND OF THE HRRR AND LOCAL WRF. ONLY CARRYING ISOLATED TO SCATTERED THUNDERSTORMS AS SURFACE DEW POINTS ACROSS THE MOUNTAINS ARE IN THE M50S-L60S. DEW POINTS ACROSS THE NC FOOTHILLS ARE IN THE M/U 60S. THERE IS ALSO A FAIR AMOUNT OF DRY AIR ALOFT. CLOUDS IN THE EAST ARE KEEPING TEMPERATURES COOLER THIS AFTERNOON. HAVE NOT SEEN ANY EVIDENCE THAT THESE LOW CLOUDS ARE EXPANDING OR ERODING EARLY THIS AFTERNOON. THEREFORE WILL KEEP THE PIEDMONT COOLER THROUGH THE REST OF THE AFTERNOON COMPARED TO AREAS WEST. TEMPERATURES ACROSS THE FOOTHILLS AND MOUNTAINS ARE COOLER THAN PREVIOUS COUPLE OF DAYS AND SHOULD WARM INTO THE L/M 80S THIS AFTERNOON. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... AS OF 300 AM EDT SUNDAY... WEAK SURFACE HIGH PRESSURE OFF THE NEW ENGLAND COAST ON MONDAY IS FORECAST TO DRIFT OFFSHORE TUESDAY AS NEXT SHORT WAVE TROF APPROACHES THE BLACKSBURG FORECAST AREA FROM THE WEST...BEGINNING TO SUBTLY FLATTEN THE UPPER RIDGE THAT WILL HAVE BUILT NORTHWEST FROM OFF THE SOUTHEAST COAST. SURFACE WINDS ON BACKSIDE OF DEPARTING SURFACE HIGH...AND IN ADVANCE OF APPROACHING SURFACE TROF WILL GRADUALLY VEER INTO THE SOUTHEAST EAST OF THE BLUE RIDGE ON MONDAY...AND INTO THE SOUTH ON TUESDAY... WHILE WINDS REMAIN MORE SOUTHWESTERLY WEST OF THE BLUE RIDGE. THIS CONFLUENT FLOW...WITH UPSLOPING ON BOTH THE EAST AND WEST SIDE OF THE APPALACHIANS...COUPLED WITH WEAK WARM MOIST ADVECTION AS TROPICAL AIRMASS SLOWLY CREEPS BACK INTO THE MID APPALACHIAN AND MID ATLANTIC REGION WILL SUPPORT DAILY REDEVELOPMENT OF SHOWERS/THUNDERSTORMS WITHIN AN UNCAPPED ENVIRONMENT. DAILY DEVELOPMENT WILL LIKELY BE MAXIMIZED ALONG AND NEAR THE FLANKS OF THE APPALACHIANS WHERE CONFLUENCE AND DIFFERENTIAL HEATING WILL BE MAXIMIZED...WITH STORMS MORE OF A SCATTERED NATURE ELSEWHERE... ESPECIALLY ACROSS THE NORTHEASTERN PORTION OF THE FORECAST AREA WHERE A SLIGHTLY DRIER AND MORE STABLE AIRMASS WILL LINGER CLOSER TO THE DEPARTING SURFACE RIDGE. WITH GRADUAL BUILDING HEIGHTS OVER THE AREA THROUGH THE SHORT TERM PERIOD...MID LEVEL LAPSE RATES WILL REMAIN RELATIVELY WEAK SUCH THAT SEVERE THREAT SHOULD BE MINIMIZED AND CONFINED TO ISOLATED WIND THREATS WHERE PRECIPITATION LOADING CAN BE MAXIMIZED. OF GREATER CONCERN IS LACK OF SIGNIFICANT STEERING WINDS THROUGH ABOUT 15K FEET...SUCH THAT ERRATIC DRIFTING STORM MOVEMENT MAY RESULT IN LOCALIZED EXCESSIVE RAINFALL. WITH LACK OF SIGNIFICANT FORCING TO SUPPORT A MORE WIDESPREAD SIGNIFICANT RAINFALL EVENT...AND ONLY SPOTTY HEAVY RAINS RECENTLY OVER THE PAST SEVERAL DAYS...SEE NO NEED TO POST ANY HYDROLOGIC-BASED WATCH AT THE PRESENT TIME. ALTHOUGH SHOWER/THUNDERSTORM ACTIVITY WILL BE MAXIMIZED DURING AFTERNOON/EVENING PERIODS...FORECAST SOUNDINGS INDICATE SUFFICIENT INSTABILITY WILL PERSIST TO MAINTAIN PRECIPITATION THREAT EVEN LATER AT NIGHT WHEREVER FORCED ASCENT/WEAK UPSLOPING CAN BE MAINTAINED. THIS THREAT FURTHER SUPPORTED WITH PLENTY OF VERY WEAK AND SMALL UPSTREAM SHORT WAVES EMBEDDED IN UPPER FLOW THAT ARE FORECAST TO RIDE AROUND PERIPHERY OF BUILDING UPPER RIDGE THROUGH THE PERIOD...MOST NOTABLY ON TUESDAY NIGHT AS MORE POTENT SHORT WAVE TROF AND ASSOCIATED COOL FRONT APPROACHES THE AREA FROM THE WEST. MOS GUIDANCE CONTINUES TO BE QUITE CONSISTENT THROUGH THE PERIOD AND GENERALLY ACCEPTED WITH DAYTIME HIGHS MAINLY IN THE 80S...WITH 70S CONFINED TO THE HIGHER ELEVATIONS...AND WITH OVERNIGHT LOWS GENERALLY BE IN THE 60S. DEVIATIONS WILL LIKELY BE GOVERNED BY LOCALIZED MORE PERSISTENT CLOUD COVER AND/OR BY COOL OUTFLOW BOUNDARIES GENERATED BY PASSING SHOWERS/STORMS. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 140 PM EDT SATURDAY... I WOULD NOT EXPECT TOO MUCH CHANGE THIS FORECAST PERIOD. FRONTAL BOUNDARY WILL SITUATE ITSELF NEAR THE AREA WED-THU THEN LIFT BACK NORTH INTO FRIDAY AND SATURDAY AS HEIGHTS BUILD YET AGAIN. OVERALL...THERE WILL BE A DAILY THREAT OF STORMS...BUT MAINLY AFTERNOON/EVENING. AT THE MOMENT BEST THREAT OF STORMS WILL BE WEDNESDAY WITH SHORTWAVE PIECE MOVING ACROSS DURING THE MIDDLE OF THE DAY. EXPECT THE MODELS THIS FAR OUT TO STILL HAVE TIMING ISSUES WITH WAVES ALONG THE SRN EDGE OF THE WESTERLIES. NOT GOING TO SEE TOO MUCH CHANGE IN AIRMASS AS DRIER DEWPOINTS STAY WELL NORTH OF THE MID ATLANTIC. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... AS OF 205 PM EDT SUNDAY... A FRONT WAS DRAPED FROM THE CAROLINAS BACK INTO THE TENNESSEE VALLEY. ENOUGH HIGH PRESSURE WAS BUILDING INTO THE REGION NORTH OF THIS SYSTEM. IFR-MVFR CLOUDS AND EASTERLY FLOW REMAINED OVER THE PIEDMONT (LYH- DAN) THROUGH EARLY AFTERNOON. DESPITE HIGH SUMMER SUN...THIS WEDGE IS NOT EXPANDING OR ERODING THIS AFTERNOON. ACROSS THE FOOTHILLS AND MOUNTAINS...THE LOW LEVEL FLOW WAS NORTHWESTERLY. THESE TWO FLOWS CONVERGE ACROSS THE BLUE RIDGE AND THE FOOTHILLS. SINCE THIS AREA IS OUTSIDE OF THE CLOUD BOUNDARY...DIFFERENTIAL HEATING SHOULD ALLOW CONVECTION TO DEVELOP THIS AFTERNOON. INSTABILITIES ARE CURRENTLY LOW WHICH SHOULD KEEP ANY CONVECTION LIMITED TO SCATTERED AREAL COVERAGE WITH A POSSIBLE FEW STORMS BECOMING STRONG. ANY CONVECTION WILL MAINLY BE DIURNALLY DRIVEN AND FADE WITH LOSE OF HEATING. ALSO WITH LOSE OF HEATING...EASTERLY FLOW AND CLOUD DECK ACROSS THE PIEDMONT MAY EXPAND EASTWARD BRING LOW IFR-MVFR DECK TO THE BLUE RIDGE. EXTENDED AVIATION DISCUSSION... DEEPER MOISTURE RETURNS NORTH...WITH BETTER COVERAGE OF AFTERNOON/EVENING STORMS ON MONDAY ESPCLY MOUNTAINS AHEAD OF ANOTHER UPPER TROF AND FRONT TO THE WEST. THIS BOUNDARY WILL GET CLOSER TUESDAY INTO WEDNESDAY WITH AT LEAST DIURNAL DAILY ROUNDS OF SHOWERS AND STORMS LIKELY TUESDAY INTO WEDNESDAY INCLUDING PERIODS OF MVFR/IFR. MAY SEE SOME IMPROVEMENT ON THURSDAY AS THE FRONT WASHES OUT OVERHEAD BUT STILL ENOUGH MOISTURE WITH HEATING FOR ADDED DIURNAL CONVECTION AGAIN THURSDAY AFTERNOON WITH PERIODS OF MVFR POSSIBLE. AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE NIGHT/EARLY MORNING... PARTICULARLY IN AREAS THAT SEE RAIN THE PREVIOUS AFTERNOON. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS/RCS SHORT TERM...WERT LONG TERM...WP AVIATION...RCS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1028 AM EDT SUN JUN 22 2014 .SYNOPSIS... WEDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA TODAY AND TONIGHT. MOISTURE WILL RETURN AGAIN BY MONDAY...RESULTING IN A DAILY THREAT SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY. A COLD FRONT WILL APPROACH FROM THE NORTHWEST BY THE MIDDLE OF THE WEEK...BRINGING IN MORE WIDESPREAD SHOWERS AND STORMS. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1028 AM EDT SUNDAY... FORECAST AREA REMAINS BETWEEN UPPER LOW OVER THE NORTHEAST UNITED STATES AND UPPER RIDGE OVER THE SOUTHERN PLAINS TODAY AND TONIGHT. NO DISTINCT SHORT WAVES COMING THROUGH THE UPPER FLOW BUT 500 MB TEMPERATURES DO DROP A FEW DEGREES BY THIS AFTERNOON. ENOUGH HIGH SURFACE HIGH PRESSURE WAS BUILD IN EAST OF THE BLUE RIDGE THAT WINDS HAVE COME AROUND TO THE NORTHEAST. LOW CLOUDS HAVE DEVELOPED IN THE WEDGE AND SPREAD WEST TOWARD THE BLUE RIDGE. OVER THE MOUNTAINS THE WIND WAS LIGHT FROM THE WEST. THIS WILL CREATE DIFFERENTIAL HEATING DURING THE DAY AND SOME LOW LEVEL CONVERGENCE. THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE ALONG THE CONVERGENCE ZONE ON THE WEST SIDE OF THE LOW CLOUDS WHERE INSTABILITY WILL BE BETTER. BUFKIT SHOWED THE THICKNESS OF THE STRATUS WILL ONLY BE A FEW HUNDRED FEET AND THE SUMMER SUN WILL GRADUALLY ERODE THE LAYER. AS THE CLOUDS ERODE AND RETREAT BACK THE EAST THE CHANCE OF SHOWERS AND THUNDERSTORMS WILL ALSO SHIFT EAST. HRRR AND OTHER SHORT TERM GUIDANCE SHOWED STORMS DEVELOPING NORTH OF THE FORECAST AREA THEN MOVING SOUTH AND EXTENDING FROM BATH COUNTY TO SURRY COUNTY BY LATE AFTERNOON. CLOUDS WILL ALSO CREATE A LARGER SPREAD IN MAXIMUM TEMPERATURES FOR TODAY. THE SOONER THE CLOUDS MIX OUT THE WARMER IT WILL BE IN THE EAST. LOW LEVEL MOISTURE FORECASTS SUGGEST CLOUDS WILL FILL BACK IN EAST OF THE BLUE RIDGE OVERNIGHT. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... AS OF 300 AM EDT SUNDAY... WEAK SURFACE HIGH PRESSURE OFF THE NEW ENGLAND COAST ON MONDAY IS FORECAST TO DRIFT OFFSHORE TUESDAY AS NEXT SHORT WAVE TROF APPROACHES THE BLACKSBURG FORECAST AREA FROM THE WEST...BEGINNING TO SUBTLY FLATTEN THE UPPER RIDGE THAT WILL HAVE BUILT NORTHWEST FROM OFF THE SOUTHEAST COAST. SURFACE WINDS ON BACKSIDE OF DEPARTING SURFACE HIGH...AND IN ADVANCE OF APPROACHING SURFACE TROF WILL GRADUALLY VEER INTO THE SOUTHEAST EAST OF THE BLUE RIDGE ON MONDAY...AND INTO THE SOUTH ON TUESDAY... WHILE WINDS REMAIN MORE SOUTHWESTERLY WEST OF THE BLUE RIDGE. THIS CONFLUENT FLOW...WITH UPSLOPING ON BOTH THE EAST AND WEST SIDE OF THE APPALACHIANS...COUPLED WITH WEAK WARM MOIST ADVECTION AS TROPICAL AIRMASS SLOWLY CREEPS BACK INTO THE MID APPALACHIAN AND MID ATLANTIC REGION WILL SUPPORT DAILY REDEVELOPMENT OF SHOWERS/THUNDERSTORMS WITHIN AN UNCAPPED ENVIRONMENT. DAILY DEVELOPMENT WILL LIKELY BE MAXIMIZED ALONG AND NEAR THE FLANKS OF THE APPALACHIANS WHERE CONFLUENCE AND DIFFERENTIAL HEATING WILL BE MAXIMIZED...WITH STORMS MORE OF A SCATTERED NATURE ELSEWHERE... ESPECIALLY ACROSS THE NORTHEASTERN PORTION OF THE FORECAST AREA WHERE A SLIGHTLY DRIER AND MORE STABLE AIRMASS WILL LINGER CLOSER TO THE DEPARTING SURFACE RIDGE. WITH GRADUAL BUILDING HEIGHTS OVER THE AREA THROUGH THE SHORT TERM PERIOD...MID LEVEL LAPSE RATES WILL REMAIN RELATIVELY WEAK SUCH THAT SEVERE THREAT SHOULD BE MINIMIZED AND CONFINED TO ISOLATED WIND THREATS WHERE PRECIPITATION LOADING CAN BE MAXIMIZED. OF GREATER CONCERN IS LACK OF SIGNIFICANT STEERING WINDS THROUGH ABOUT 15K FEET...SUCH THAT ERRATIC DRIFTING STORM MOVEMENT MAY RESULT IN LOCALIZED EXCESSIVE RAINFALL. WITH LACK OF SIGNIFICANT FORCING TO SUPPORT A MORE WIDESPREAD SIGNIFICANT RAINFALL EVENT...AND ONLY SPOTTY HEAVY RAINS RECENTLY OVER THE PAST SEVERAL DAYS...SEE NO NEED TO POST ANY HYDROLOGIC-BASED WATCH AT THE PRESENT TIME. ALTHOUGH SHOWER/THUNDERSTORM ACTIVITY WILL BE MAXIMIZED DURING AFTERNOON/EVENING PERIODS...FORECAST SOUNDINGS INDICATE SUFFICIENT INSTABILITY WILL PERSIST TO MAINTAIN PRECIPITATION THREAT EVEN LATER AT NIGHT WHEREVER FORCED ASCENT/WEAK UPSLOPING CAN BE MAINTAINED. THIS THREAT FURTHER SUPPORTED WITH PLENTY OF VERY WEAK AND SMALL UPSTREAM SHORT WAVES EMBEDDED IN UPPER FLOW THAT ARE FORECAST TO RIDE AROUND PERIPHERY OF BUILDING UPPER RIDGE THROUGH THE PERIOD...MOST NOTABLY ON TUESDAY NIGHT AS MORE POTENT SHORT WAVE TROF AND ASSOCIATED COOL FRONT APPROACHES THE AREA FROM THE WEST. MOS GUIDANCE CONTINUES TO BE QUITE CONSISTENT THROUGH THE PERIOD AND GENERALLY ACCEPTED WITH DAYTIME HIGHS MAINLY IN THE 80S...WITH 70S CONFINED TO THE HIGHER ELEVATIONS...AND WITH OVERNIGHT LOWS GENERALLY BE IN THE 60S. DEVIATIONS WILL LIKELY BE GOVERNED BY LOCALIZED MORE PERSISTENT CLOUD COVER AND/OR BY COOL OUTFLOW BOUNDARIES GENERATED BY PASSING SHOWERS/STORMS. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 140 PM EDT SATURDAY... I WOULD NOT EXPECT TOO MUCH CHANGE THIS FORECAST PERIOD. FRONTAL BOUNDARY WILL SITUATE ITSELF NEAR THE AREA WED-THU THEN LIFT BACK NORTH INTO FRIDAY AND SATURDAY AS HEIGHTS BUILD YET AGAIN. OVERALL...THERE WILL BE A DAILY THREAT OF STORMS...BUT MAINLY AFTERNOON/EVENING. AT THE MOMENT BEST THREAT OF STORMS WILL BE WEDNESDAY WITH SHORTWAVE PIECE MOVING ACROSS DURING THE MIDDLE OF THE DAY. EXPECT THE MODELS THIS FAR OUT TO STILL HAVE TIMING ISSUES WITH WAVES ALONG THE SRN EDGE OF THE WESTERLIES. NOT GOING TO SEE TOO MUCH CHANGE IN AIRMASS AS DRIER DEWPOINTS STAY WELL NORTH OF THE MID ATLANTIC. && .AVIATION /15Z SUNDAY THROUGH THURSDAY/... AS OF 745 AM EDT SUNDAY... LOW PRESSURE WAS OVER SOUTHEAST NORTH CAROLINA WITH A FRONT TRAILING BACK INTO THE TENNESSEE VALLEY. ENOUGH HIGH PRESSURE WAS BUILDING INTO THE REGION NORTH OF THIS SYSTEM. FIRST VISIBLE SATELLITE PICTURES OF THE DAY SHOWERS A LAYER OF MVFR STRATUS JUST EAST OF KROA...WITH SEVERAL BREAKS IN THE CLOUD DECK.THIS CLOUD LAYER WAS SHALLOW AND CLOUDS WILL ERODE IN THE MORNING WITH HEATING. MODERATE CONFIDENCE THAT A MAJORITY OF THE LOW CLOUDS WILL BE GONE BY 14Z/10AM. ALONG THE EDGE OF THIS RELATIVELY MORE STABLE AIR...EXPECT THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS BY AFTERNOON. MOST LIKELY LOCATION FOR STORM IS ALONG A CORRIDOR FROM KHSP TO KMWK...SO HAVE ADDED THUNDER IN THE VCNTY TO THE KBCB/KROA AND KLYH TAFS AFTER 21Z/5PM. MUCH OF THE PRECIPITATION WILL DIMINISH WITH THE LOSS OF HEATING THIS EVENING. CEILINGS MAY LOWER AGAIN OVERNIGHT...ESPECIALLY EAST OF THE BLUE RIDGE. MODELS HAVE MVFR CLOUDS MOVING BACK IN...MAINLY AFTER 08Z/4AM. EXTENDED AVIATION DISCUSSION... DEEPER MOISTURE RETURNS NORTH...WITH BETTER COVERAGE OF AFTERNOON/EVENING STORMS ON MONDAY ESPCLY MOUNTAINS AHEAD OF ANOTHER UPPER TROF AND FRONT TO THE WEST. THIS BOUNDARY WILL GET CLOSER TUESDAY INTO WEDNESDAY WITH AT LEAST DIURNAL DAILY ROUNDS OF SHOWERS AND STORMS LIKELY TUESDAY INTO WEDNESDAY INCLUDING PERIODS OF MVFR/IFR. MAY SEE SOME IMPROVEMENT ON THURSDAY AS THE FRONT WASHES OUT OVERHEAD BUT STILL ENOUGH MOISTURE WITH HEATING FOR ADDED DIURNAL CONVECTION AGAIN THURSDAY AFTERNOON WITH PERIODS OF MVFR POSSIBLE. AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE NIGHT/EARLY MORNING... PARTICULARLY IN AREAS THAT SEE RAIN THE PREVIOUS AFTERNOON. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS/RCS SHORT TERM...WERT LONG TERM...WP AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
747 AM EDT SUN JUN 22 2014 .SYNOPSIS... WEDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA TODAY AND TONIGHT. MOISTURE WILL RETURN AGAIN BY MONDAY...RESULTING IN A DAILY THREAT SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY. A COLD FRONT WILL APPROACH FROM THE NORTHWEST BY THE MIDDLE OF THE WEEK...BRINGING IN MORE WIDESPREAD SHOWERS AND STORMS. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 345 AM EDT SUNDAY... FORECAST AREA REMAINS BETWEEN UPPER LOW OVER THE NORTHEAST UNITED STATES AND UPPER RIDGE OVER THE SOUTHERN PLAINS TODAY AND TONIGHT. NO DISTINCT SHORT WAVES COMING THROUGH THE UPPER FLOW BUT 500 MB TEMPERATURES DO DROP A FEW DEGREES BY THIS AFTERNOON. ENOUGH HIGH SURFACE HIGH PRESSURE WAS BUILD IN EAST OF THE BLUE RIDGE THAT WINDS HAVE COME AROUND TO THE NORTHEAST. LOW CLOUDS HAVE DEVELOPED IN THE WEDGE AND SPREAD WEST TOWARD THE BLUE RIDGE. OVER THE MOUNTAINS THE WIND WAS LIGHT FROM THE WEST. THIS WILL CREATE DIFFERENTIAL HEATING DURING THE DAY AND SOME LOW LEVEL CONVERGENCE. THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE ALONG THE CONVERGENCE ZONE ON THE WEST SIDE OF THE LOW CLOUDS WHERE INSTABILITY WILL BE BETTER. BUFKIT SHOWED THE THICKNESS OF THE STRATUS WILL ONLY BE A FEW HUNDRED FEET AND THE SUMMER SUN WILL GRADUALLY ERODE THE LAYER. AS THE CLOUDS ERODE AND RETREAT BACK THE EAST THE CHANCE OF SHOWERS AND THUNDERSTORMS WILL ALSO SHIFT EAST. HRRR AND OTHER SHORT TERM GUIDANCE SHOWED STORMS DEVELOPING NORTH OF THE FORECAST AREA THEN MOVING SOUTH AND EXTENDING FROM BATH COUNTY TO SURRY COUNTY BY LATE AFTERNOON. CLOUDS WILL ALSO CREATE A LARGER SPREAD IN MAXIMUM TEMPERATURES FOR TODAY. THE SOONER THE CLOUDS MIX OUT THE WARMER IT WILL BE IN THE EAST. LOW LEVEL MOISTURE FORECASTS SUGGEST CLOUDS WILL FILL BACK IN EAST OF THE BLUE RIDGE OVERNIGHT. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... AS OF 300 AM EDT SUNDAY... WEAK SURFACE HIGH PRESSURE OFF THE NEW ENGLAND COAST ON MONDAY IS FORECAST TO DRIFT OFFSHORE TUESDAY AS NEXT SHORT WAVE TROF APPROACHES THE BLACKSBURG FORECAST AREA FROM THE WEST...BEGINNING TO SUBTLY FLATTEN THE UPPER RIDGE THAT WILL HAVE BUILT NORTHWEST FROM OFF THE SOUTHEAST COAST. SURFACE WINDS ON BACKSIDE OF DEPARTING SURFACE HIGH...AND IN ADVANCE OF APPROACHING SURFACE TROF WILL GRADUALLY VEER INTO THE SOUTHEAST EAST OF THE BLUE RIDGE ON MONDAY...AND INTO THE SOUTH ON TUESDAY... WHILE WINDS REMAIN MORE SOUTHWESTERLY WEST OF THE BLUE RIDGE. THIS CONFLUENT FLOW...WITH UPSLOPING ON BOTH THE EAST AND WEST SIDE OF THE APPALACHIANS...COUPLED WITH WEAK WARM MOIST ADVECTION AS TROPICAL AIRMASS SLOWLY CREEPS BACK INTO THE MID APPALACHIAN AND MID ATLANTIC REGION WILL SUPPORT DAILY REDEVELOPMENT OF SHOWERS/THUNDERSTORMS WITHIN AN UNCAPPED ENVIRONMENT. DAILY DEVELOPMENT WILL LIKELY BE MAXIMIZED ALONG AND NEAR THE FLANKS OF THE APPALACHIANS WHERE CONFLUENCE AND DIFFERENTIAL HEATING WILL BE MAXIMIZED...WITH STORMS MORE OF A SCATTERED NATURE ELSEWHERE... ESPECIALLY ACROSS THE NORTHEASTERN PORTION OF THE FORECAST AREA WHERE A SLIGHTLY DRIER AND MORE STABLE AIRMASS WILL LINGER CLOSER TO THE DEPARTING SURFACE RIDGE. WITH GRADUAL BUILDING HEIGHTS OVER THE AREA THROUGH THE SHORT TERM PERIOD...MID LEVEL LAPSE RATES WILL REMAIN RELATIVELY WEAK SUCH THAT SEVERE THREAT SHOULD BE MINIMIZED AND CONFINED TO ISOLATED WIND THREATS WHERE PRECIPITATION LOADING CAN BE MAXIMIZED. OF GREATER CONCERN IS LACK OF SIGNIFICANT STEERING WINDS THROUGH ABOUT 15K FEET...SUCH THAT ERRATIC DRIFTING STORM MOVEMENT MAY RESULT IN LOCALIZED EXCESSIVE RAINFALL. WITH LACK OF SIGNIFICANT FORCING TO SUPPORT A MORE WIDESPREAD SIGNIFICANT RAINFALL EVENT...AND ONLY SPOTTY HEAVY RAINS RECENTLY OVER THE PAST SEVERAL DAYS...SEE NO NEED TO POST ANY HYDROLOGIC-BASED WATCH AT THE PRESENT TIME. ALTHOUGH SHOWER/THUNDERSTORM ACTIVITY WILL BE MAXIMIZED DURING AFTERNOON/EVENING PERIODS...FORECAST SOUNDINGS INDICATE SUFFICIENT INSTABILITY WILL PERSIST TO MAINTAIN PRECIPITATION THREAT EVEN LATER AT NIGHT WHEREVER FORCED ASCENT/WEAK UPSLOPING CAN BE MAINTAINED. THIS THREAT FURTHER SUPPORTED WITH PLENTY OF VERY WEAK AND SMALL UPSTREAM SHORT WAVES EMBEDDED IN UPPER FLOW THAT ARE FORECAST TO RIDE AROUND PERIPHERY OF BUILDING UPPER RIDGE THROUGH THE PERIOD...MOST NOTABLY ON TUESDAY NIGHT AS MORE POTENT SHORT WAVE TROF AND ASSOCIATED COOL FRONT APPROACHES THE AREA FROM THE WEST. MOS GUIDANCE CONTINUES TO BE QUITE CONSISTENT THROUGH THE PERIOD AND GENERALLY ACCEPTED WITH DAYTIME HIGHS MAINLY IN THE 80S...WITH 70S CONFINED TO THE HIGHER ELEVATIONS...AND WITH OVERNIGHT LOWS GENERALLY BE IN THE 60S. DEVIATIONS WILL LIKELY BE GOVERNED BY LOCALIZED MORE PERSISTENT CLOUD COVER AND/OR BY COOL OUTFLOW BOUNDARIES GENERATED BY PASSING SHOWERS/STORMS. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 140 PM EDT SATURDAY... I WOULD NOT EXPECT TOO MUCH CHANGE THIS FORECAST PERIOD. FRONTAL BOUNDARY WILL SITUATE ITSELF NEAR THE AREA WED-THU THEN LIFT BACK NORTH INTO FRIDAY AND SATURDAY AS HEIGHTS BUILD YET AGAIN. OVERALL...THERE WILL BE A DAILY THREAT OF STORMS...BUT MAINLY AFTERNOON/EVENING. AT THE MOMENT BEST THREAT OF STORMS WILL BE WEDNESDAY WITH SHORTWAVE PIECE MOVING ACROSS DURING THE MIDDLE OF THE DAY. EXPECT THE MODELS THIS FAR OUT TO STILL HAVE TIMING ISSUES WITH WAVES ALONG THE SRN EDGE OF THE WESTERLIES. NOT GOING TO SEE TOO MUCH CHANGE IN AIRMASS AS DRIER DEWPOINTS STAY WELL NORTH OF THE MID ATLANTIC. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... AS OF 745 AM EDT SUNDAY... LOW PRESSURE WAS OVER SOUTHEAST NORTH CAROLINA WITH A FRONT TRAILING BACK INTO THE TENNESSEE VALLEY. ENOUGH HIGH PRESSURE WAS BUILDING INTO THE REGION NORTH OF THIS SYSTEM. FIRST VISIBLE SATELLITE PICTURES OF THE DAY SHOWERS A LAYER OF MVFR STRATUS JUST EAST OF KROA...WITH SEVERAL BREAKS IN THE CLOUD DECK.THIS CLOUD LAYER WAS SHALLOW AND CLOUDS WILL ERODE IN THE MORNING WITH HEATING. MODERATE CONFIDENCE THAT A MAJORITY OF THE LOW CLOUDS WILL BE GONE BY 14Z/10AM. ALONG THE EDGE OF THIS RELATIVELY MORE STABLE AIR...EXPECT THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS BY AFTERNOON. MOST LIKELY LOCATION FOR STORM IS ALONG A CORRIDOR FROM KHSP TO KMWK...SO HAVE ADDED THUNDER IN THE VCNTY TO THE KBCB/KROA AND KLYH TAFS AFTER 21Z/5PM. MUCH OF THE PRECIPITATION WILL DIMINISH WITH THE LOSS OF HEATING THIS EVENING. CEILINGS MAY LOWER AGAIN OVERNIGHT...ESPECIALLY EAST OF THE BLUE RIDGE. MODELS HAVE MVFR CLOUDS MOVING BACK IN...MAINLY AFTER 08Z/4AM. EXTENDED AVIATION DISCUSSION... DEEPER MOISTURE RETURNS NORTH...WITH BETTER COVERAGE OF AFTERNOON/EVENING STORMS ON MONDAY ESPCLY MOUNTAINS AHEAD OF ANOTHER UPPER TROF AND FRONT TO THE WEST. THIS BOUNDARY WILL GET CLOSER TUESDAY INTO WEDNESDAY WITH AT LEAST DIURNAL DAILY ROUNDS OF SHOWERS AND STORMS LIKELY TUESDAY INTO WEDNESDAY INCLUDING PERIODS OF MVFR/IFR. MAY SEE SOME IMPROVEMENT ON THURSDAY AS THE FRONT WASHES OUT OVERHEAD BUT STILL ENOUGH MOISTURE WITH HEATING FOR ADDED DIURNAL CONVECTION AGAIN THURSDAY AFTERNOON WITH PERIODS OF MVFR POSSIBLE. AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE NIGHT/EARLY MORNING... PARTICULARLY IN AREAS THAT SEE RAIN THE PREVIOUS AFTERNOON. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS SHORT TERM...WERT LONG TERM...WP AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
406 AM EDT SUN JUN 22 2014 .SYNOPSIS... WEDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA TODAY AND TONIGHT. MOISTURE WILL RETURN AGAIN BY MONDAY...RESULTING IN A DAILY THREAT SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY. A COLD FRONT WILL APPROACH FROM THE NORTHWEST BY THE MIDDLE OF THE WEEK...BRINGING IN MORE WIDESPREAD SHOWERS AND STORMS. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 345 AM EDT SUNDAY... FORECAST AREA REMAINS BETWEEN UPPER LOW OVER THE NORTHEAST UNITED STATES AND UPPER RIDGE OVER THE SOUTHERN PLAINS TODAY AND TONIGHT. NO DISTINCT SHORT WAVES COMING THROUGH THE UPPER FLOW BUT 500 MB TEMPERATURES DO DROP A FEW DEGREES BY THIS AFTERNOON. ENOUGH HIGH SURFACE HIGH PRESSURE WAS BUILD IN EAST OF THE BLUE RIDGE THAT WINDS HAVE COME AROUND TO THE NORTHEAST. LOW CLOUDS HAVE DEVELOPED IN THE WEDGE AND SPREAD WEST TOWARD THE BLUE RIDGE. OVER THE MOUNTAINS THE WIND WAS LIGHT FROM THE WEST. THIS WILL CREATE DIFFERENTIAL HEATING DURING THE DAY AND SOME LOW LEVEL CONVERGENCE. THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE ALONG THE CONVERGENCE ZONE ON THE WEST SIDE OF THE LOW CLOUDS WHERE INSTABILITY WILL BE BETTER. BUFKIT SHOWED THE THICKNESS OF THE STRATUS WILL ONLY BE A FEW HUNDRED FEET AND THE SUMMER SUN WILL GRADUALLY ERODE THE LAYER. AS THE CLOUDS ERODE AND RETREAT BACK THE EAST THE CHANCE OF SHOWERS AND THUNDERSTORMS WILL ALSO SHIFT EAST. HRRR AND OTHER SHORT TERM GUIDANCE SHOWED STORMS DEVELOPING NORTH OF THE FORECAST AREA THEN MOVING SOUTH AND EXTENDING FROM BATH COUNTY TO SURRY COUNTY BY LATE AFTERNOON. CLOUDS WILL ALSO CREATE A LARGER SPREAD IN MAXIMUM TEMPERATURES FOR TODAY. THE SOONER THE CLOUDS MIX OUT THE WARMER IT WILL BE IN THE EAST. LOW LEVEL MOISTURE FORECASTS SUGGEST CLOUDS WILL FILL BACK IN EAST OF THE BLUE RIDGE OVERNIGHT. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... AS OF 300 AM EDT SUNDAY... WEAK SURFACE HIGH PRESSURE OFF THE NEW ENGLAND COAST ON MONDAY IS FORECAST TO DRIFT OFFSHORE TUESDAY AS NEXT SHORT WAVE TROF APPROACHES THE BLACKSBURG FORECAST AREA FROM THE WEST...BEGINNING TO SUBTLY FLATTEN THE UPPER RIDGE THAT WILL HAVE BUILT NORTHWEST FROM OFF THE SOUTHEAST COAST. SURFACE WINDS ON BACKSIDE OF DEPARTING SURFACE HIGH...AND IN ADVANCE OF APPROACHING SURFACE TROF WILL GRADUALLY VEER INTO THE SOUTHEAST EAST OF THE BLUE RIDGE ON MONDAY...AND INTO THE SOUTH ON TUESDAY... WHILE WINDS REMAIN MORE SOUTHWESTERLY WEST OF THE BLUE RIDGE. THIS CONFLUENT FLOW...WITH UPSLOPING ON BOTH THE EAST AND WEST SIDE OF THE APPALACHIANS...COUPLED WITH WEAK WARM MOIST ADVECTION AS TROPICAL AIRMASS SLOWLY CREEPS BACK INTO THE MID APPALACHIAN AND MID ATLANTIC REGION WILL SUPPORT DAILY REDEVELOPMENT OF SHOWERS/THUNDERSTORMS WITHIN AN UNCAPPED ENVIRONMENT. DAILY DEVELOPMENT WILL LIKELY BE MAXIMIZED ALONG AND NEAR THE FLANKS OF THE APPALACHIANS WHERE CONFLUENCE AND DIFFERENTIAL HEATING WILL BE MAXIMIZED...WITH STORMS MORE OF A SCATTERED NATURE ELSEWHERE... ESPECIALLY ACROSS THE NORTHEASTERN PORTION OF THE FORECAST AREA WHERE A SLIGHTLY DRIER AND MORE STABLE AIRMASS WILL LINGER CLOSER TO THE DEPARTING SURFACE RIDGE. WITH GRADUAL BUILDING HEIGHTS OVER THE AREA THROUGH THE SHORT TERM PERIOD...MID LEVEL LAPSE RATES WILL REMAIN RELATIVELY WEAK SUCH THAT SEVERE THREAT SHOULD BE MINIMIZED AND CONFINED TO ISOLATED WIND THREATS WHERE PRECIPITATION LOADING CAN BE MAXIMIZED. OF GREATER CONCERN IS LACK OF SIGNIFICANT STEERING WINDS THROUGH ABOUT 15K FEET...SUCH THAT ERRATIC DRIFTING STORM MOVEMENT MAY RESULT IN LOCALIZED EXCESSIVE RAINFALL. WITH LACK OF SIGNIFICANT FORCING TO SUPPORT A MORE WIDESPREAD SIGNIFICANT RAINFALL EVENT...AND ONLY SPOTTY HEAVY RAINS RECENTLY OVER THE PAST SEVERAL DAYS...SEE NO NEED TO POST ANY HYDROLOGIC-BASED WATCH AT THE PRESENT TIME. ALTHOUGH SHOWER/THUNDERSTORM ACTIVITY WILL BE MAXIMIZED DURING AFTERNOON/EVENING PERIODS...FORECAST SOUNDINGS INDICATE SUFFICIENT INSTABILITY WILL PERSIST TO MAINTAIN PRECIPITATION THREAT EVEN LATER AT NIGHT WHEREVER FORCED ASCENT/WEAK UPSLOPING CAN BE MAINTAINED. THIS THREAT FURTHER SUPPORTED WITH PLENTY OF VERY WEAK AND SMALL UPSTREAM SHORT WAVES EMBEDDED IN UPPER FLOW THAT ARE FORECAST TO RIDE AROUND PERIPHERY OF BUILDING UPPER RIDGE THROUGH THE PERIOD...MOST NOTABLY ON TUESDAY NIGHT AS MORE POTENT SHORT WAVE TROF AND ASSOCIATED COOL FRONT APPROACHES THE AREA FROM THE WEST. MOS GUIDANCE CONTINUES TO BE QUITE CONSISTENT THROUGH THE PERIOD AND GENERALLY ACCEPTED WITH DAYTIME HIGHS MAINLY IN THE 80S...WITH 70S CONFINED TO THE HIGHER ELEVATIONS...AND WITH OVERNIGHT LOWS GENERALLY BE IN THE 60S. DEVIATIONS WILL LIKELY BE GOVERNED BY LOCALIZED MORE PERSISTENT CLOUD COVER AND/OR BY COOL OUTFLOW BOUNDARIES GENERATED BY PASSING SHOWERS/STORMS. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 140 PM EDT SATURDAY... I WOULD NOT EXPECT TOO MUCH CHANGE THIS FORECAST PERIOD. FRONTAL BOUNDARY WILL SITUATE ITSELF NEAR THE AREA WED-THU THEN LIFT BACK NORTH INTO FRIDAY AND SATURDAY AS HEIGHTS BUILD YET AGAIN. OVERALL...THERE WILL BE A DAILY THREAT OF STORMS...BUT MAINLY AFTERNOON/EVENING. AT THE MOMENT BEST THREAT OF STORMS WILL BE WEDNESDAY WITH SHORTWAVE PIECE MOVING ACROSS DURING THE MIDDLE OF THE DAY. EXPECT THE MODELS THIS FAR OUT TO STILL HAVE TIMING ISSUES WITH WAVES ALONG THE SRN EDGE OF THE WESTERLIES. NOT GOING TO SEE TOO MUCH CHANGE IN AIRMASS AS DRIER DEWPOINTS STAY WELL NORTH OF THE MID ATLANTIC. && .AVIATION /08Z SUNDAY THROUGH THURSDAY/... AS OF 130 AM EDT SUNDAY... LOW PRESSURE WAS OVER EASTERN NORTH CAROLINA WITH A FRONT TRAILING BACK INTO THE TENNESSEE VALLEY. ENOUGH HIGH PRESSURE WAS BUILDING INTO THE REGION NORTH OF THIS SYSTEM TO BRING SURFACE WINDS AROUND TO THE NORTHEAST AT KROA/KLYH/KDAN. A LAYER OF STRATUS WAS ADVANCING WEST TOWARD THE BLUE RIDGE AND IS EXPECTED TO REACH KROA AROUND THE START OF THE 06Z TAF PERIOD. MORE QUESTIONABLE IF WEDGE AND LOW CLOUDS WILL MAKE IT INTO KBCB. FOR NOW HAVE KEPT IFR CEILINGS OUT OF THE KBCB FORECAST. WEDGE IS SHALLOW AND CLOUDS WILL ERODE IN THE MORNING WITH HEATING. ALONG THE EDGE OF THIS RELATIVELY MORE STABLE AIR...MODERATE CONFIDENCE OF THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS BY AFTERNOON. ANY PRECIPITATION WILL DIMINISH WITH THE LOSS OF HEATING THIS EVENING. CEILINGS MAY LOWER AGAIN OVERNIGHT...ESPECIALLY EAST OF THE BLUE RIDGE. LOW CONFIDENCE ON TIMING...SO FOR NOW HAVE LEFT RETURN OF IFR CEILINGS OUT OF TAFS. EXTENDED AVIATION DISCUSSION... DEEPER MOISTURE RETURNS NORTH...WITH BETTER COVERAGE OF AFTERNOON/EVENING STORMS ON MONDAY ESPCLY MOUNTAINS AHEAD OF ANOTHER UPPER TROF AND FRONT TO THE WEST. THIS BOUNDARY WILL GET CLOSER TUESDAY INTO WEDNESDAY WITH AT LEAST DIURNAL DAILY ROUNDS OF SHOWERS AND STORMS LIKELY TUESDAY INTO WEDNESDAY INCLUDING PERIODS OF MVFR/IFR. MAY SEE SOME IMPROVEMENT ON THURSDAY AS THE FRONT WASHES OUT OVERHEAD BUT STILL ENOUGH MOISTURE WITH HEATING FOR ADDED DIURNAL CONVECTION AGAIN THURSDAY AFTERNOON WITH PERIODS OF MVFR POSSIBLE. AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE NIGHT/EARLY MORNING... PARTICULARLY IN AREAS THAT SEE RAIN THE PREVIOUS AFTERNOON. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS SHORT TERM...WERT LONG TERM...WP AVIATION...AMS/JH
YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML

  [top] Area Forecast Discussion National Weather Service Spokane WA 822 PM PDT MON JUN 23 2014 .SYNOPSIS... Following the warmest weather of the season so far...temperatures will return to normal Tuesday with the arrival of a cold front. Tuesday`s cold front will also bring a good chance of showers and thunderstorms to the Inland Northwest as well as gusty winds. The Thursday through Sunday time frame will also feature a chance of showers and thunderstorms...and will once again accompany gusty winds. && .DISCUSSION... Update: Water vapor satellite from this evening showed an upper level wave moving into Western Washington and Oregon. Radar imagery shows a narrow area of rain associated with a mid level front. As this front crosses the Cascades overnight...it will be moving into an area of dry lower levels. However sufficient mid level moisture and lift should be enough to bring scattered showers to the East Slopes (numerous showers near the Cascade crest), with isolated showers into the Okanogan Valley, Wenatchee area, and western Columbia basin. Some minor POP increases have been made based on radar trends and the latest 00z HRRR showing the eastern edge of the showers tonight making it into Moses Lake. For Eastern Washington and North Idaho the chance of showers will hold off til Tuesday morning when the mid level front swings through. The warm day today followed by increased cloud cover tonight will yield a mild night for the Inland Northwest with valley lows mainly in the mid 50s to lower 60s. JW && .AVIATION... 00Z TAFS: An upper level trough and an associated cold front will cross the Cascades overnight reaching Eastern Washington and North Idaho on Tuesday. Scattered showers are expected along the front and then afternoon sun breaks will destabilize the atmosphere Tuesday afternoon over northern and eastern Washington as well as the Idaho Panhandle. Isolated thunderstorms are expected with KGEG/KSFF/KCOE/KPUW/KLWS included in this threat. However with only isolated coverage expected around the TAF sites VCSH was maintained for the afternoon with no mention of TS. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 60 74 53 77 56 72 / 0 30 10 10 30 40 Coeur d`Alene 56 73 50 76 53 70 / 0 40 20 10 40 50 Pullman 54 73 48 76 53 71 / 0 30 10 10 60 60 Lewiston 61 80 55 84 60 75 / 0 20 10 10 60 60 Colville 53 75 48 78 53 74 / 10 60 20 10 10 40 Sandpoint 51 73 46 75 49 68 / 10 60 30 20 40 50 Kellogg 53 74 49 74 51 69 / 10 40 30 20 40 60 Moses Lake 63 85 55 84 61 83 / 20 20 0 10 10 20 Wenatchee 67 83 58 83 63 82 / 20 20 0 10 10 20 Omak 61 81 51 83 58 83 / 20 50 10 10 10 20 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
636 PM CDT MON JUN 23 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 313 PM CDT MON JUN 23 2014 THE MAIN FOCUS INTO TOMORROW IS WITH HOW LONG THE ISOLATED CONVECTION WILL HOLD ON FOR THIS AFTERNOON/EVENING AND THEN WITH THE PRECIPITATION CHANCES TOMORROW. CLOUD COVER HAS BEEN SLOW TO ERODE TODAY AS A COLD FRONT APPROACHES FROM THE WEST AND A MID LEVEL TROUGH PROPAGATES NORTHEAST FROM IOWA INTO THE WESTERN GREAT LAKES. SOME ISOLATED CONVECTION HAS INITIATED ALONG A COLD FRONT IN SOUTHEAST MINNESOTA WHERE MLCAPE IS AROUND 500-1000 J/KG. THE COMBINATION OF THE APPROACHING MID LEVEL SHORT WAVE TROUGH AND THE SLOW MOVING SURFACE BOUNDARY HAS LEAD TO SOME FUNNEL CLOUDS FORMING CLOSER TO THE TWIN CITIES. THIS DEVELOPMENT WILL REMAIN POSSIBLE FOR A FEW HOURS HERE BEFORE THE SUN STARTS TO SET AND SB/MLCAPE STARTS TO DROP OFF. THE PAST FEW RUNS OF THE HRRR HAVE DEVELOPED SOME SMALL COLD POOLS WITH THIS CONVECTION AND TRIES TO KEEP IT GOING THROUGH THE EARLY EVENING HOURS ACROSS WESTERN WISCONSIN. THINKING THAT THESE SOLUTIONS ARE A BIT OVERDONE AS IT HAS SURFACE TEMPERATURES GETTING INTO THE 90S...BUT WILL KEEP SOME PRECIPITATION CHANCES GOING INTO THE EVENING AHEAD OF THIS FRONT. THE FOCUS THEN GOES INTO TOMORROW AS A MID LEVEL TROUGH CURRENTLY OVER SOUTHERN MANITOBA DROPS DOWN INTO THE REGION. THE STRONGEST 500-300MB PV ADVECTION RUNS FROM SOUTHERN MINNESOTA THROUGH CENTRAL WISCONSIN AS THE SURFACE COLD FRONT DRIFTS DOWN INTO THE REGION. THE THINKING IS THAT THE HIGHEST CHANCES FOR ANY SHOWERS/STORMS SHOULD BE ALONG THIS CORRIDOR. THE 23.12Z GUIDANCE ALL SUGGEST THAT MLCAPE SHOULD REMAIN FAIRLY TAME AT 500-1000 J/KG AHEAD OF THE FRONT WITH LITTLE TO NO DEEP SHEAR TO WORK WITH...SO SUSPECT THAT ANY CONVECTION WILL REMAIN OF THE PULSE NATURE. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 313 PM CDT MON JUN 23 2014 WITH THIS COLD FRONT TO THE SOUTH OF THE REGION THROUGH THE REST OF THE WORK WEEK...TEMPERATURES WILL BE SEASONAL OR JUST BELOW SEASONAL UNTIL IT GETS KICKED BACK TO THE NORTH AS A WARM FRONT BY NEXT WEEKEND. UNTIL THEN...CONFIDENCE IN PRECIPITATION CHANCES IS NOT VERY HIGH AS MUCH OF IT WILL DEPEND ON WHETHER ANY CONVECTIVE SYSTEMS TRACK ALONG THE BOUNDARY TO THE SOUTH AND WE SEE THE NORTHERN OVERHANG OF IT. THE 23.12Z GFS/ECMWF HAVE ZONAL FLOW OVER THE REGION FOR WEDNESDAY YET HAS SOME CONVECTION DEVELOPING ALONG THE COLD FRONT/TROUGH THAT THEY HAVE ANALYZED ACROSS THE AREA. THE 23.12Z NAM...MEANWHILE...HAS THE REGION MAINLY DRY EXCEPT FOR A PORTION OF THE FRONT IN CENTRAL IOWA WHERE IT BUILDS SURFACE DEW POINTS INTO THE MID 70S AND TAKES MLCAPE UP TOO HIGH. SO...THERE IS NOT A LOT OF CONFIDENCE IN THE PRECIPITATION CHANCES THROUGH THE END OF THE WEEK BUT AT LEAST EXPECT THAT THE RAINS WILL NOT BE ALL DAY DEALS AND JUST SOME PERIODS WHERE THIS CONVECTION IS POSSIBLE. A PATTERN CHANGE TAKES PLACE FOR NEXT WEEKEND AS A DEEPER MID LEVEL TROUGH DEVELOPS ACROSS THE HIGH PLAINS. THIS FEATURE STALLS OUT AND A NUMBER OF SHORT WAVE TROUGHS ROUND THE SOUTHEASTERN PERIPHERY OF IT ACROSS THE UPPER MISSISSIPPI RIVER VALLEY. THIS COULD LEAD TO A MORE ACTIVE PERIOD SEVERE WEATHER-WISE WITH STRONG 500MB WINDS OVERHEAD TO GO ALONG WITH AN UNSTABLE AIR MASS. DETAILS WILL FALL OUT THROUGH THE WEEK...BUT THIS APPEARS TO BE THE TIME FRAME TO WATCH FOR POTENTIAL SEVERE WEATHER. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 636 PM CDT MON JUN 23 2014 DECAYING SHOWERS AND ISOLATED THUNDERSTORMS AHEAD OF COOL FRONT SHOULD CONTINUE TO WANE WITH LOSS OF DIURNAL HEATING AS THEY APPROACH KLSE THIS EVENING. NO FOG CONCERNS OVERNIGHT WITH WINDS STAYING UP AND A SLIGHTLY DRIER AIR MASS IN PLACE. OTHERWISE...PLAN ON VFR CONDITIONS INTO TUESDAY WITH NORTHWEST WINDS IN PLACE. AN APPROACHING FRONT TUESDAY AFTERNOON COULD SPARK SOME SHOWERS AND ISOLATED THUNDERSTORMS BY MID TO LATE AFTERNOON. && .HYDROLOGY... ISSUED AT 313 PM CDT MON JUN 23 2014 WHILE THERE ARE CHANCES FOR PRECIPITATION THROUGH THIS WEEK...THE CHANCES FOR HEAVY RAINFALL ARE LOW WITH MOST OF THE BETTER MOISTURE TRANSPORT STAYING SOUTH OF THE REGION. HOWEVER...THERE STILL IS A LOT OF WATER COMING DOWN THE RIVERS FROM CENTRAL MINNESOTA WHERE HEAVY RAIN FELL LAST WEEK. EXPECT AREA RIVERS...ESPECIALLY THE MAIN STEMS...TO STAY UP THROUGH THE WEEK. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...HALBACH LONG TERM...HALBACH AVIATION...ZT HYDROLOGY...HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
334 PM CDT SUN JUN 22 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 334 PM CDT SUN JUN 22 2014 THE MAIN FOCUS THROUGH TOMORROW IS ON CONVECTIVE TRENDS AND WHETHER ANY FLASH FLOODING IS STILL POSSIBLE. AN MCV FROM OVERNIGHT HAS COME THROUGH MUCH OF THE REGION FROM LATE THIS MORNING INTO THE EARLY AFTERNOON HOURS AND HAS KICKED UP A BAND OF CONVECTION/RAIN OUT AHEAD OF IT. MUCH OF THE 22.12Z GUIDANCE HAS NOT DONE A VERY GOOD JOB OF PICKING UP ON THIS FEATURE AND STILL WANT TO DEVELOP A WIDE SWATH OF CONVECTION ACROSS THE REGION THIS EVENING. THE HRRR HAS DONE A DECENT JOB OF CAPTURING THIS CONVECTION AND CLEARS MOST OF THE REGION FROM THE WEST EARLY THIS EVENING. THE MOST UNSTABLE AIR MASS APPEARS TO STAY OUT AHEAD OF THE MCV...SO AM NOT EXPECTING MUCH IN THE WAY OF SEVERE DEVELOPMENT BEHIND IT. CONFIDENCE IS NOT VERY HIGH WITH HOW TONIGHT WILL PAN OUT WITH THE MAIN COLD FRONT STILL OFF TO THE WEST...SO WILL KEEP THE FLASH FLOOD WATCH GOING FOR THE TIME BEING AND LET THE EVENING PLAY OUT A BIT MORE BEFORE CANNING IT. THE 22.12Z NAM/GFS/GEM DID TREND FASTER WITH PUSHING THE PRECIPITATION/MID LEVEL TROUGH/SFC LOW OFF TO THE EAST TOMORROW MORNING...SO HAVE TRENDED A BIT FASTER WITH ENDING THE RAIN CHANCES TOMORROW. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 334 PM CDT SUN JUN 22 2014 A BRIEF DRY PERIOD IS EXPECTED MONDAY NIGHT INTO TUESDAY MORNING AS SUBSIDENT AIR COMES IN THE WAKE OF THE TROUGH. ANOTHER COLD FRONT WILL DROP DOWN FROM CANADA TUESDAY AFTERNOON AND BRING THE NEXT CHANCE OF RAIN ALONG WITH IT. SKINNY CAPE PROFILE WITH THIS FEATURE WITH LESS THAN 1000 J/KG OF MLCAPE EXPECTED...SO NOT THINKING THAT THIS WILL BE A SEVERE WEATHER PRODUCER AT THIS POINT. AFTER THAT FRONT DROPS TO THE SOUTH IT APPEARS TO STALL OUT FROM THE HIGH PLAINS ON DOWN SOUTHEAST THROUGH THE MID MISSISSIPPI RIVER VALLEY. CONFIDENCE NOT VERY HIGH WITH OUR PRECIPITATION CHANCES TOWARD THE END OF THE WEEK...BUT ALSO DID NOT HAVE MUCH OF A CHANCE TO DIG INTO THE DETAILS WITH CONVECTION ON GOING...SO HAVE GONE WITH THE CONSENSUS OF THE MODEL BLENDS FOR NOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1243 PM CDT SUN JUN 22 2014 A LINE OF STRONG TO SEVERE THUNDERSTORMS WILL MOVE THROUGH KLSE AROUND 22.1830Z. THE MAIN THREATS ARE DAMAGING WINDS AND LARGE HAIL. ISOLATED TORNADOES ARE ALSO POSSIBLE. ADDITIONAL THUNDERSTORMS ARE LIKELY TO DEVELOP IN THE WAKE OF THIS INITIAL LINE THIS AFTERNOON AND EVENING AS A COLD FRONT APPROACHES THE AREA. THESE THUNDERSTORMS WILL COME TO AN END AS THE COLD FRONT PASSES THROUGH KRST AT 23.10Z AND KLSE AT 23.12Z. THE THUNDERSTORMS MAY BRIEFLY PRODUCE IFR/MVFR CEILINGS AND VISIBILITIES. && .HYDROLOGY... ISSUED AT 334 PM CDT SUN JUN 22 2014 HEAVY RAINFALL FROM LAST WEEK HAS PRIMED THE GROUND FOR ADDITIONAL FLOODING WITH ANY STORMS THAT MAY MOVE THROUGH. THE STORMS TODAY HAD SOME BRIEFLY INTENSE RAINFALL RATES AT ABOUT 2 INCHES PER HOUR THOUGH THEY ONLY LASTED FOR ABOUT A HALF HOUR. MANY AREA RIVERS ARE STILL ELEVATED FROM THE RECENT RAINFALL AND WILL LIKELY STAY THAT WAY THROUGH THE WEEK. CONFIDENCE IS NOT VERY HIGH AT THIS POINT ABOUT WHETHER THE FLASH FLOOD WATCH IS STILL NECESSARY FOR TONIGHT...BUT WANT TO MAKE SURE THAT CONDITIONS WILL BE OKAY BEFORE DROPPING IT. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLASH FLOOD WATCH THROUGH MONDAY AFTERNOON FOR WIZ017-029- 032>034-041-042-053>055-061. MN...FLASH FLOOD WATCH THROUGH MONDAY AFTERNOON FOR MNZ079-086>088- 094>096. IA...FLASH FLOOD WATCH THROUGH MONDAY AFTERNOON FOR IAZ008>011-018- 019-029-030. && $$ SHORT TERM...HALBACH LONG TERM...HALBACH AVIATION...BOYNE HYDROLOGY...HALBACH
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1211 PM CDT SUN JUN 22 2014 .UPDATE...VISIBILITIES CONTINUE TO IMPROVE IN THE EASTERN COUNTIES...AS DAYTIME HEATING STARTS TO MIX THE BOUNDARY LAYER. SHOULD SEE LOW STRATUS DECK IN THAT AREA CONTINUE TO MIX OUT AS WELL BY EARLY THIS AFTERNOON. DIURNAL CUMULUS SHOULD DEVELOP IN THE WAKE OF THE LOW STRATUS. HIGHS LOOK ON TRACK...RANGING FROM THE 60S NEAR THE LAKE TO THE MID 80S WEST AND SOUTH OF MADISON. OTHER ISSUE IS CONVECTIVE POTENTIAL THIS AFTERNOON WITH LINE OF STORMS MOVING TOWARD THE AREA FROM SOUTHEAST MINNESOTA AND EASTERN IOWA. THESE BEING DRIVEN BY CONVECTIVELY INDUCED VORTICITY MAXIMUM ENTERING WESTERN IOWA. MEAN LAYER CAPES SHOULD INCREASE TO 1000 TO 1500 J/KG IN THE WESTERN PORTIONS OF THE AREA...AND COULD GET SOMEWHAT HIGHER INTO THIS AFTERNOON. DEEP LAYER SHEAR IS RELATIVELY WEAK...AROUND 20 KNOTS OR SO...SO NOT SURE HOW WIDESPREAD ANY SEVERE WEATHER MAY BE IN OUR FAR WESTERN COUNTIES. HRRR HAVING TROUBLE WITH CURRENT TRENDS...WITH 4 KM WRF/NMM KEEPING EVERYTHING JUST WEST OF THE AREA THIS AFTERNOON. SPC HAS FAR WEST IN SLIGHT RISK FOR SEVERE STORMS THIS AFTERNOON...AND HAVE PUT THE FAR WESTERN THREE COUNTIES IN A SEVERE THUNDERSTORM WATCH UNTIL 00Z MONDAY. WILL CERTAINLY HAVE TO WATCH STORM TRENDS AS THEY SHIFT CLOSER TO THIS AREA...GIVEN THE AMOUNT OF INSTABILITY AVAILABLE. WILL ADD PROGRESSIVELY HIGHER POPS FOR THUNDER INTO THE WESTERN COUNTIES FOR THE AFTERNOON. && .AVIATION/18Z TAFS/...VFR CONDITIONS WILL RETURN TO EASTERN TAF SITES BY 18Z TO 19Z SUNDAY...AS LAST OF LOW STRATUS CLOUDS MIX OUT. DIURNAL CUMULUS CLOUDS WILL DEVELOP DURING THE AFTERNOON...WITH LIGHT WINDS. LINE OF THUNDERSTORMS IN SOUTHEAST MINNESOTA AND EASTERN IOWA MAY AFFECT MADISON AFTER 21Z SUNDAY. GIVEN UNCERTAINTY WITH HOW FAR EAST THESE STORMS MAY REACH...WILL JUST MENTION VICINITY THUNDER IN MADISON BETWEEN 21Z SUNDAY AND 00Z MONDAY. SHOULD SEE SOME LIGHT FOG AND POSSIBLY SOME LOW STRATUS CLOUDS TONIGHT INTO EARLY MONDAY MORNING...DOWN TO NEAR ALTERNATE MINIMUMS. NOT EXPECTING DENSE FOG AGAIN...AS WINDS ABOVE THE SURFACE SHOULD BE STRONGER THAN LAST NIGHT. LOW PRESSURE WILL MOVE NORTHEAST THROUGH THE REGION TONIGHT AND MONDAY...WITH A COLD FRONTAL PASSAGE LATER MONDAY AFTERNOON OR MONDAY EVENING. SHOWERS AND THUNDERSTORMS ARE EXPECTED MAINLY AFTER 06Z MONDAY AND THROUGH THE DAY MONDAY. MVFR/IFR VISIBILITIES ARE POSSIBLE IN ANY STORMS...WITH SOME GUSTY WINDS. && .MARINE...DENSE FOG ADVISORY WILL CONTINUE FOR THE NEARSHORE WATERS UNTIL AT LEAST 15Z MONDAY. WARM AND MOIST AIRMASS WILL REMAIN OVER THE COOL LAKE WATERS DURING THIS TIME...AND WILL REMAIN THERE UNTIL COLD FRONT MOVES THROUGH THE AREA MONDAY EVENING. SO...MAY NEED TO EXTEND THE ADVISORY INTO MONDAY EVENING IN LATER FORECASTS. && .PREV DISCUSSION... /ISSUED 342 AM CDT SUN JUN 22 2014/ SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM. MADE A RATHER SHARP DEVIATION FROM THE PREVIOUS FORECAST FOR THE NEXT 24 HRS. THE MODELS HAVE SLOWED DOWN THE ARRIVAL OF THE NEXT TROF...WITH SHORT WAVE RIDGING AND A DRY COLUMN NOW EXPECTED TO KEEP THE AREA RAIN FREE THROUGH 06Z TONIGHT. IN THE VERY SHORT TERM...CALM WINDS...DAMP GROUND...A VERY SATURATED BOUNDARY LAYER AND SOME INFLUENCE FROM LAKE MICHIGAN HAS LEAD TO WIDESPREAD DENSE FOG ACROSS THE SOUTHEAST. THE WESTERN EDGE IS TOUGH TO DETERMINE BUT IS SOMEWHERE BETWEEN WATERTOWN AND MADISON. SOME BLOWOFF CIRRUS FROM CONVECTION UPSTREAM IS HELPING TO KEEP SOUTH CENTRAL AREAS IN BETTER SHAPE. THE SOUTHEAST IS ALSO UNDER THE INFLUENCE OF A COOLER SOUTHEAST FLOW OFF THE LAKE. ALBEIT A VERY LIGHT FLOW...BUT IT/S ENOUGH. A DENSE FOG ADVISORY IS IN EFFECT UNTIL 9 AM FOR ALL BUT THE FAR WRN TIER OF COUNTIES. I MAY HAVE TO TRIM ANOTHER TIER OUT OF THE ADVISORY EARLY IF MSN DOESN/T DETERIORATE SOON. THE NEXT TROF BEGINS TO INFLUENCE THE AREA AFTER MIDNIGHT WITH SOME DEEP Q-VECTOR CONVERGENCE IMPINGING ON THE AREA. THE LEADING WARM ADVECTION IS UNIMPRESSIVE SO DON/T SEE MUCH NEED TO TRY TO BRING THIS IN FASTER THAN THE BULK OF THE GUIDANCE SUGGESTS. CAPE LOOKS WEAK WITH LOW LEVEL CAPPING. ANY THUNDER WILL BE ELEVATED AND NOT VERY STRONG. WE COULD SEE SOME FOG AGAIN IN THE EAST AS THE FLOW WILL BE ONSHORE AGAIN. MONDAY AND MONDAY NIGHT...FORECAST CONFIDENCE MEDIUM. THE VERY SLOW-MOVING MID LEVEL SHORTWAVE WILL TRACK ACROSS WISCONSIN ON MONDAY. VORTICITY ADVECTION...RIGHT ENTRANCE REGION OF THE UPPER JET...STRONG 700MB OMEGA AND FRONTOGENESIS LINE UP OVER SOUTHERN WI MIDDAY MONDAY. RAISED POPS TO CATEGORICAL FOR MUCH OF THE DAY. EXPECTING SCATTERED THUNDERSTORMS GIVEN TALL SKINNY CAPE OF AROUND 1500 J/KG AND 20 KT BULK SHEAR AND THE FOCUSED SYNOPTIC FORCING. PRECIPITABLE WATER VALUES OF AROUND 1.75 INCHES AND LOW MBE VELOCITIES SHOW THE POTENTIAL FOR HEAVY RAIN OVER THE AREA. RAIN WILL TAPER OFF FROM WEST TO EAST FROM LATE AFTERNOON THROUGH EVENING. THE GFS IS SLOWER TO END THE PRECIP THAN THE NAM AND ECMWF. LONG TERM... TUESDAY...FORECAST CONFIDENCE MEDIUM. EXPECTING QUIET WEATHER FOR MOST OF THE DAY TUESDAY WITH DRIER AIR OVERHEAD AND LACK OF ANY FORCING. A SURFACE TO 850MB COLD FRONT STATIONED ACROSS NORTHERN WI WILL DROP DOWN THROUGH SOUTHERN WI TUE NIGHT. THERE IS A CHANCE OF SHOWERS AND MAYBE A THUNDERSTORM ALONG THIS FRONT OVERNIGHT. WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE LOW. THE STALLED 925-850MB FRONT OVER SOUTHWEST WI WILL BE THE FOCUS FOR POSSIBLE SHOWERS AND A FEW THUNDERSTORMS ON WEDNESDAY WITH A WEAK SHORTWAVE ROLLING THROUGH. THEN THAT BOUNDARY MAY LIFT INTO NORTHERN WI FOR THE REST OF THE WEEK AND KEEP SOUTHERN WI ON THE WARM AND CAPPED SIDE OF THE FRONT PER THE 00Z ECMWF...OR IT COULD STALL RIGHT OVER SOUTHERN WI AND CONTINUE TO BE THE FOCUS FOR ROUNDS OF SHOWERS AND THUNDERSTORMS EACH DAY PER THE GFS. THEREFORE...THERE IS A CHANCE FOR SHOWERS AND THUNDERSTORMS EVERY TIME PERIOD IN THE EXTENDED FORECAST. TEMPERATURES WILL DEPEND ON THE PRECIP CHANCES. WENT WITH CONSENSUS FORECAST VALUES. THE ONE MORE CERTAIN THING IS THAT EASTERLY WINDS WILL PREVAIL THROUGH THE EXTENDED AND KEEP LAKESHORE TEMPS COOLER. AVIATION/12Z TAFS/... LIFR CONDITIONS WILL CONTINUE ACROSS THE SOUTHEAST THROUGH ABOUT 14- 15Z WITH GRADUALLY IMPROVING CONDITIONS THEREAFTER. THE RAP AND AMDAR AIRCRAFT SOUNDINGS INDICATE THIS STUFF IS 2-3KFT THICK. THIS LOOKS VERY SIMILAR TO YESTERDAY. THE RAP HAS THIS MIXING OUT BY AROUND NOON...GIVE OR TAKE...JUST LIKE YESTERDAY...SO SEE NO REASON TO DISAGREE. THERE SHOULD ONLY BE SOME HIGH CLOUDS AROUND ONCE THE LOW STUFF SCATTERS OUT. FOR THE AIR SHOW...HOWEVER...WE SHOULD STILL SEE SOME LOWER CLOUDS AND FOG OVER THE WATER DUE TO THE MOIST BOUNDARY LAYER AIR MOVING LITTLE OVER THE COLD WATERS OF THE LAKE. IT/S POSSIBLE LAKE AREAS WILL CLEAR OUT...BUT CONFIDENCE IS LOW IN THESE SITUATIONS. FOR KMSN...IMPROVEMENT WILL LIKELY OCCUR MUCH QUICKER WITH VFR CONDITIONS LIKELY BY 14Z. AN EASTERLY FLOW CONTINUING TONIGHT COULD BRING IN SOME LOWER VSBYS AGAIN TO THE SOUTHEAST...BUT THERE WILL BE MUCH MORE FLOW ABOVE THE DECOUPLED BOUNDARY LAYER SO NOT EXPECTING VSBYS TO BE AS LOW OR FOR THERE TO BE MUCH IN THE WAY OF LOW STRATUS. THUNDERSTORMS ARE POSSIBLE AT KMSN TOWARD 12Z MON AS A TROF APPROACHES FROM THE WEST. MARINE... HAVE EXTENDED THE MARINE DENSE FOG ADVISORY AGAIN...THIS TIME TO 15Z MON...OR 10 AM MON. JUST NOT SEEING MUCH PATTERN CHANGE OR REASON FOR SIGGY IMPROVEMENT. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...DENSE FOG ADVISORY UNTIL 10 AM CDT MONDAY FOR LMZ643>646. && $$ UPDATE...WOOD TODAY/TONIGHT AND AVIATION/MARINE...DAVIS MONDAY THROUGH SATURDAY...MRC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
342 AM CDT SUN JUN 22 2014 .SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM. MADE A RATHER SHARP DEVIATION FROM THE PREVIOUS FORECAST FOR THE NEXT 24 HRS. THE MODELS HAVE SLOWED DOWN THE ARRIVAL OF THE NEXT TROF...WITH SHORT WAVE RIDGING AND A DRY COLUMN NOW EXPECTED TO KEEP THE AREA RAIN FREE THROUGH 06Z TONIGHT. IN THE VERY SHORT TERM...CALM WINDS...DAMP GROUND...A VERY SATURATED BOUNDARY LAYER AND SOME INFLUENCE FROM LAKE MICHIGAN HAS LEAD TO WIDESPREAD DENSE FOG ACROSS THE SOUTHEAST. THE WESTERN EDGE IS TOUGH TO DETERMINE BUT IS SOMEWHERE BETWEEN WATERTOWN AND MADISON. SOME BLOWOFF CIRRUS FROM CONVECTION UPSTREAM IS HELPING TO KEEP SOUTH CENTRAL AREAS IN BETTER SHAPE. THE SOUTHEAST IS ALSO UNDER THE INFLUENCE OF A COOLER SOUTHEAST FLOW OFF THE LAKE. ALBEIT A VERY LIGHT FLOW...BUT IT/S ENOUGH. A DENSE FOG ADVISORY IS IN EFFECT UNTIL 9 AM FOR ALL BUT THE FAR WRN TIER OF COUNTIES. I MAY HAVE TO TRIM ANOTHER TIER OUT OF THE ADVISORY EARLY IF MSN DOESN/T DETERIORATE SOON. THE NEXT TROF BEGINS TO INFLUENCE THE AREA AFTER MIDNIGHT WITH SOME DEEP Q-VECTOR CONVERGENCE IMPINGING ON THE AREA. THE LEADING WARM ADVECTION IS UNIMPRESSIVE SO DON/T SEE MUCH NEED TO TRY TO BRING THIS IN FASTER THAN THE BULK OF THE GUIDANCE SUGGESTS. CAPE LOOKS WEAK WITH LOW LEVEL CAPPING. ANY THUNDER WILL BE ELEVATED AND NOT VERY STRONG. WE COULD SEE SOME FOG AGAIN IN THE EAST AS THE FLOW WILL BE ONSHORE AGAIN. MONDAY AND MONDAY NIGHT...FORECAST CONFIDENCE MEDIUM. THE VERY SLOW-MOVING MID LEVEL SHORTWAVE WILL TRACK ACROSS WISCONSIN ON MONDAY. VORTICITY ADVECTION...RIGHT ENTRANCE REGION OF THE UPPER JET...STRONG 700MB OMEGA AND FRONTOGENESIS LINE UP OVER SOUTHERN WI MIDDAY MONDAY. RAISED POPS TO CATEGORICAL FOR MUCH OF THE DAY. EXPECTING SCATTERED THUNDERSTORMS GIVEN TALL SKINNY CAPE OF AROUND 1500 J/KG AND 20 KT BULK SHEAR AND THE FOCUSED SYNOPTIC FORCING. PRECIPITABLE WATER VALUES OF AROUND 1.75 INCHES AND LOW MBE VELOCITIES SHOW THE POTENTIAL FOR HEAVY RAIN OVER THE AREA. RAIN WILL TAPER OFF FROM WEST TO EAST FROM LATE AFTERNOON THROUGH EVENING. THE GFS IS SLOWER TO END THE PRECIP THAN THE NAM AND ECMWF. .LONG TERM... TUESDAY...FORECAST CONFIDENCE MEDIUM. EXPECTING QUIET WEATHER FOR MOST OF THE DAY TUESDAY WITH DRIER AIR OVERHEAD AND LACK OF ANY FORCING. A SURFACE TO 850MB COLD FRONT STATIONED ACROSS NORTHERN WI WILL DROP DOWN THROUGH SOUTHERN WI TUE NIGHT. THERE IS A CHANCE OF SHOWERS AND MAYBE A THUNDERSTORM ALONG THIS FRONT OVERNIGHT. WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE LOW. THE STALLED 925-850MB FRONT OVER SOUTHWEST WI WILL BE THE FOCUS FOR POSSIBLE SHOWERS AND A FEW THUNDERSTORMS ON WEDNESDAY WITH A WEAK SHORTWAVE ROLLING THROUGH. THEN THAT BOUNDARY MAY LIFT INTO NORTHERN WI FOR THE REST OF THE WEEK AND KEEP SOUTHERN WI ON THE WARM AND CAPPED SIDE OF THE FRONT PER THE 00Z ECMWF...OR IT COULD STALL RIGHT OVER SOUTHERN WI AND CONTINUE TO BE THE FOCUS FOR ROUNDS OF SHOWERS AND THUNDERSTORMS EACH DAY PER THE GFS. THEREFORE...THERE IS A CHANCE FOR SHOWERS AND THUNDERSTORMS EVERY TIME PERIOD IN THE EXTENDED FORECAST. TEMPERATURES WILL DEPEND ON THE PRECIP CHANCES. WENT WITH CONSENSUS FORECAST VALUES. THE ONE MORE CERTAIN THING IS THAT EASTERLY WINDS WILL PREVAIL THROUGH THE EXTENDED AND KEEP LAKESHORE TEMPS COOLER. && .AVIATION/12Z TAFS/... LIFR CONDITIONS WILL CONTINUE ACROSS THE SOUTHEAST THROUGH ABOUT 14- 15Z WITH GRADUALLY IMPROVING CONDITIONS THEREAFTER. THE RAP AND AMDAR AIRCRAFT SOUNDINGS INDICATE THIS STUFF IS 2-3KFT THICK. THIS LOOKS VERY SIMILAR TO YESTERDAY. THE RAP HAS THIS MIXING OUT BY AROUND NOON...GIVE OR TAKE...JUST LIKE YESTERDAY...SO SEE NO REASON TO DISAGREE. THERE SHOULD ONLY BE SOME HIGH CLOUDS AROUND ONCE THE LOW STUFF SCATTERS OUT. FOR THE AIR SHOW...HOWEVER...WE SHOULD STILL SEE SOME LOWER CLOUDS AND FOG OVER THE WATER DUE TO THE MOIST BOUNDARY LAYER AIR MOVING LITTLE OVER THE COLD WATERS OF THE LAKE. IT/S POSSIBLE LAKE AREAS WILL CLEAR OUT...BUT CONFIDENCE IS LOW IN THESE SITUATIONS. FOR KMSN...IMPROVEMENT WILL LIKELY OCCUR MUCH QUICKER WITH VFR CONDITIONS LIKELY BY 14Z. AN EASTERLY FLOW CONTINUING TONIGHT COULD BRING IN SOME LOWER VSBYS AGAIN TO THE SOUTHEAST...BUT THERE WILL BE MUCH MORE FLOW ABOVE THE DECOUPLED BOUNDARY LAYER SO NOT EXPECTING VSBYS TO BE AS LOW OR FOR THERE TO BE MUCH IN THE WAY OF LOW STRATUS. THUNDERSTORMS ARE POSSIBLE AT KMSN TOWARD 12Z MON AS A TROF APPROACHES FROM THE WEST. && .MARINE... HAVE EXTENDED THE MARINE DENSE FOG ADVISORY AGAIN...THIS TIME TO 15Z MON...OR 10 AM MON. JUST NOT SEEING MUCH PATTERN CHANGE OR REASON FOR SIGGY IMPROVEMENT. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR WIZ046-047- 051-052-057>060-063>066-068>072. LM...DENSE FOG ADVISORY UNTIL 10 AM CDT MONDAY FOR LMZ643>646. && $$ TODAY/TONIGHT AND AVIATION/MARINE...DAVIS MONDAY THROUGH SATURDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1151 PM CDT SAT JUN 21 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 345 PM CDT SAT JUN 21 2014 AT 3 PM...A MESOSCALE CONVECTIVE VORTICITY...GENERATED FROM THE THUNDERSTORMS IN NEBRASKA AND SOUTH DAKOTA LAST EVENING...WAS MOVING EAST THROUGH SOUTHERN WISCONSIN. THIS SYSTEM IS GENERATING SHOWERS AND A FEW THUNDERSTORMS IN AN AREA OF 2500 J/KG SURFACE CAPES. BOTH THE 21.12Z ARW AND LATEST HRRR ARE IN GOOD AGREEMENT THAT A FEW SHOWERS WILL LINGER ACROSS ADAMS AND JUNEAU COUNTIES IN CENTRAL WISCONSIN THROUGH 22.03Z...AND THEN THE REMAINDER OF TONIGHT WILL BE DRY AS SUBSIDENCE BUILDS ACROSS THE AREA IN THE WAKE OF THE CONVECTIVELY INDUCED VORT MAX AND SHORT WAVE RIDGE. ON SUNDAY...THE 21.12Z MODELS ARE IN GOOD AGREEMENT THAT SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP DURING THE MORNING ACROSS SOUTHEAST MINNESOTA AND NORTHEAST IOWA AHEAD OF AN APPROACHING COLD FRONT AND SHORT WAVE TROUGH MOVING OUT OF THE CENTRAL PLAINS. THESE SHOWERS AND THUNDERSTORMS THEN BECOME MORE WIDESPREAD ACROSS THE ENTIRE FORECAST AREA AS THE UPPER LEVEL DIVERGENCE INCREASES... THE AREA ENTERS THE RIGHT ENTRANCE REGION OF A 50 KNOT 250 MB JET...AND THE SURFACE BASE CAPES CLIMB INTO THE 3-4K J/KG RANGE. WHILE THE MODELS ARE IN AGREEMENT WITH THIS...THEY DO DIFFER SOME ON HOW ORGANIZED THIS CONVECTION BECOMES DURING THE AFTERNOON. THE ARW SUGGEST A LINE OF STORMS BY EARLY AFTERNOON. MEANWHILE THE 21.12Z SPC WRF SUGGESTS THAT THE CONVECTION WILL BE LESS ORGANIZED. WHILE THE 0-3 KM AND 0-6 KM SHEAR IS NOT SUFFICIENT FOR THE DEVELOPMENT OF SUPERCELLS...THE MID LEVEL LAPSE RATES ARE RUNNING IN THE 7 TO 8 C/KM RANGE WHICH WOULD BE SUFFICIENT FOR THE DEVELOPMENT OF LARGE HAIL AND DRY AIR BELOW THE CLOUDS MAY AID IN STRENGTHENING THE DOWN DRAFTS...SO WILL HAVE TO WATCH OUT FOR PULSE SEVERE STORMS. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 345 PM CDT SAT JUN 21 2014 FROM SUNDAY NIGHT INTO MONDAY...THE CONVECTION BECOMES MORE ORGANIZED AS THE COLD FRONT AND SURFACE LOW MOVES SLOWLY THROUGH THE FORECAST AREA. STRONG 850 MB MOISTURE JET WILL RESULT IN THE DEVELOPMENT OF A MESOSCALE CONVECTIVE COMPLEX. IN ADDITION... PRECIPITABLE WATER VALUES CLIMB INTO THE 1.7 TO 1.9 INCH RANGE AND WARM CLOUD DEPTHS CLIMB TO 4 KM AHEAD OF THE SURFACE LOW. THIS WILL RESULT IN THE THREAT OF HEAVY RAIN AND POTENTIALLY SOME MORE FLOODING. WITH MODELS DEVIATING ON THE TIMING...LOCATION OF THE SURFACE LOW...AND STRENGTH OF THE SHORT WAVE TROUGH...HELD OFF ISSUING A FLOOD WATCH FOR NOW. WHILE THE 0-6 KM SHEAR REMAINS WEAK...THE 0-3 KM DOES EXCEED 30 KNOTS AND THIS COULD RESULT IN SOME WIND DAMAGE AS THE SYSTEM EVOLVES. MONDAY NIGHT IS NOW LOOKING DRY IN ALL OF THE DETERMINISTIC MODELS AS SUBSIDENCE DEVELOPS IN THE WAKE OF THE DEPARTING LOW PRESSURE SYSTEM. AS A RESULT...EITHER REDUCED OR TOOK OUT THE PRECIPITATION CHANCES ACROSS THE ENTIRE FORECAST AREA. FROM TUESDAY THROUGH THURSDAY....A CANADIAN COLD FRONT DROPS INTO THE REGION. WHILE THE MODELS HAVE BEEN CONSISTENT AT DOING THIS... THEY CONTINUE TO STRUGGLE ON HOW FAR SOUTH THIS FRONT WILL GET. THE MODELS ALSO CONTINUE TO SHOW THAT SEVERAL SHORT WAVE TROUGHS WILL MOVE ALONG THIS BOUNDARY. HOWEVER THERE IS ONLY WEAK MOISTURE TRANSPORT INTO THE REGION WHICH RESULTS IN WEAK 0-3 KM AND 0-6 KM SHEAR...THUS NOT EXPECTING ANY SEVERE WEATHER AT THIS TIME. FROM THURSDAY NIGHT INTO SATURDAY...A PATTERN SHIFT OCCURS AS A LONG WAVE TROUGH MOVES INTO THE WESTERN UNITED STATES. WHILE BOTH THE GFS AND ECMWF ARE IN AGREEMENT THAT AND UPPER LEVEL RIDGE WILL BUILD AHEAD OF THIS TROUGH...THERE CONTINUES TO BE QUESTIONS ON HOW FAR WEST THIS RIDGE WILL END UP AND THIS WILL GREATLY AFFECT WHETHER WE WILL SEE PRECIPITATION OR NOT. DUE TO THIS...JUTS STAYED WITH THE MODEL CONSENSUS FOR NOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1152 PM CDT SAT JUN 21 2014 MAIN WEATHER STORY OCCURS SUNDAY AT TAF SITES AS INSTABILITY BUILDS BACK INTO THE AREA FROM THE WEST AND STORMS LOOK MORE FAVORABLE AS THE DAY PROGRESSES. IN THE MORNING...IT APPEARS AN INSTABILITY GRADIENT WILL BE WEST OF KRST WITH DAKOTAS STORMS MOVING TO ABOUT I-35 IN MN/IA...THEN WEAKEN RAPIDLY LEAVING DEBRIS CLOUD INTO KRST AND KLSE. THERE COULD BE SOME RAIN TOO...WILL HAVE TO LET THIS FORECAST IN THE SHORT TERM...HOWEVER THERE DOES NOT LOOK TO BE A FLIGHT RESTRICTION WITH IT. LATER IN THE AFTERNOON INSTABILITY WILL BE BUILDING AND A FRONT WILL WORK OUT OF THE WEST VERY SLOWLY. VERY MOIST AIR WILL MOVE IN BY EVENING WITH INCREASING STORM AND HEAVY RAIN CHANCES...ESPECIALLY FOR KRST. AFTER 06Z...EXPECT CIGS/VSBYS TO COME DOWN IN RAIN AND STORMS. && .HYDROLOGY... ISSUED AT 345 PM CDT SAT JUN 21 2014 THE MISSISSIPPI TRIBUTARIES HAVE CRESTED AND ARE NOW FALLING. MEANWHILE THE MISSISSIPPI RIVER IS RISING WITH FLOODING EXPECTED AT WABASHA...WINONA...AND MCGREGOR. AT THIS TIME...LA CROSSE IS NOT EXPECTED TO REACH FLOOD STAGE. HOWEVER THIS COULD CHANGE DEPENDING ON HOW MUCH RAIN FALLS ON SUNDAY NIGHT. BETWEEN 1 AND 3 INCHES OF RAIN LOOKS POSSIBLE ON SUNDAY NIGHT...BUT DUE TO MODEL INCONSISTENCIES HELD OFF ISSUING A FLOOD WATCH FOR NOW. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...BAUMGARDT HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
631 PM MDT MON JUN 23 2014 .SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY) ISSUED AT 245 PM MDT MON JUN 23 2014 DEEPER CUMULUS HAVE STARTED TO DEVELOP OVER THE PAST HOUR IN THE CONVERGENCE ALONG THE SOUTHERN LARAMIE RANGE...BUT SO FAR NOT A WHOLE LOT OF UPSCALE GROWTH AS THESE CELLS HAVE MOVED INTO THE PLAINS. DEW POINTS ARE CURRENTLY IN THE UPPER 40S TO MID 50S TO THE EAST OF THE LARAMIE RANGE. THE MODELS CONTINUE TO INDICATE AN ENVIRONMENT CONDUCIVE FOR SOME STRONG TO SEVERE STORMS IN AREAS NEAR THE COLORADO BORDER THROUGH THIS EVENING. SPC MESOANALYSIS SHOWS MLCAPES OF 1000-1250 J/KG STRETCHING ALONG INTERSTATE 80 OVER THE PLAINS COMBINED WITH 35-40 KT OF BULK SHEAR. THE HRRR MODEL HAS A LONE STORM MOVING EASTWARD ALONG THE COLORADO BORDER THROUGH THE LATE AFTN. SO VERY SIMILAR TO YESTERDAY...WE CONTINUE TO EXPECT A MARGINAL SEVERE THREAT OVER LARAMIE COUNTY AND EXTENDING EASTWARD INTO THE SOUTHERN PANHANDLE. KEPT A SLIGHT CHANCE OF TSTMS GOING THROUGH THE NIGHT WITH A WEAK SHORTWAVE MOVING OVERHEAD...WHICH IS CURRENTLY ACROSS SOUTHWESTERN WY. THE REMAINDER OF THE SHORT TERM WILL FEATURE GRADUALLY INCREASING TEMPS AND INSTABILITY. FLOW ALOFT IS STILL WEST TO NORTHWESTERLY ON TUES WITH THE MID LEVEL RIDGE AXIS TO THE WEST OF THE CWA. DEW POINTS INCH UP SLIGHTLY...SO CAPE VALUES WILL INCREASE OVER TODAY WITH THE GFS SHOWING AROUND 1500 J/KG ALONG INTERSTATE 80. INSTABILITY DROPS OFF TO 750 J/KG ACROSS CONVERSE/NIOBRARA COUNTIES AND INTO THE NORTHERN NEBRASKA PANHANDLE. BEST CHANCE OF SEVERE STORMS WILL LIKELY BE OVER AREAS TO THE SOUTH OF A WHEATLAND TO SCOTTSBLUFF LINE. TEMPS ON TUES WILL BE A COUPLE DEGREES WARMER THAN THIS AFTN. THE BEST POTENTIAL FOR MORE WIDESPREAD SEVERE STORMS IS STILL LOOKING LIKE WED. A SFC LOW DEVELOPS OVER NORTH-CENTRAL WY DURING THE AFTN AND WITH PERSISTENT SOUTHEAST WINDS...ADDITIONAL MOISTURE ADVECTION HAS OCCURRED OVER THE PLAINS. DEW POINTS BY WED AFTN ARE INTO THE UPPER 50S AND LOW 60S ALMOST EVERYWHERE TO THE EAST OF THE LARAMIE RANGE WITH CAPE VALUES OF 1500-2000. ALTHOUGH FLOW ALOFT WILL BE WEAKER THAN THE PRECEDING DAYS DUE TO THE PROXIMITY OF THE RIDGE AXIS...THERE IS STILL AROUND 40 KT OF DEEP LAYER SHEAR. ITS A BIT EARLY TO PINPOINT THE AREA OVER THE PLAINS THAN HAS THE BEST POTENTIAL FOR SEVERE STORMS...BUT IT WOULD SEEM TO BE OVER THE NORTHERN HALF...WHICH IS CLOSEST TO A WEAK SHORTWAVE THAN MOVES INTO WESTERN SOUTH DAKOTA DURING THE EVENING. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 225 PM MDT MON JUN 23 2014 MINOR MODEL DIFFERENCES NOTED IN THE MEDIUM RANGE PERIOD. WEAK UPPER RIDGE OVER THE PLAINS YIELDS TO A BROADER UPPER TROUGH BY THE WEEKEND. THE SOUTHWESTERLY FLOW ALOFT VEERS TO WESTERLY. SURFACE PATTERN WILL BE FAIRLY WEAK WITH A RIDGE WEST OF THE MOUNTAINS AND TROUGH ACROSS THE PLAINS. LOW LEVEL CONVERGENCE AND MOISTURE COMBINED WITH PASSING WEAK DISTURBANCES WILL KEEP WIDELY SCATTERED SHOWERS AND TSTORMS IN THE FORECAST THURSDAY THROUGH SATURDAY. SEVERE THREAT WILL BE MINIMAL GIVEN WEAK SHEAR...BUT CANNOT RULE OUT ISOLATED STRONG CONVECTION FOR THE PLAINS. UPPER TROUGH LIFTS NORTHEAST THROUGH THE NORTHERN GREAT PLAINS AND UPPER MIDWEST SUNDAY AND MONDAY WITH DRIER WEST-NORTHWEST FLOW PATTERN. TEMPERATURES WILL AVERAGE ABOVE SEASONAL NORMALS WITH HIGHS IN THE 80S FOR LOWER ELEVATIONS WITH 60S AND 70S FOR THE HIGH COUNTRY. LOWS WILL BE IN THE 40S AND 50S. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY AFTERNOON) ISSUED AT 626 PM MDT MON JUN 23 2014 MAIN AVIATION CONCERN THIS CYCLE WILL BE THE CONTINUED CHANCES OF SHOWERS AND THUNDERSTORMS AT LEAST THROUGH 04Z AT AREA TERMINALS. THUNDERSTORMS HAVE INITIALLY BEEN SKIRTING KLAR AND KCYS...BUT SHOULD IMPACT THESE TWO AERODROMES BETWEEN 01-03Z. WILL KEEP VCTS GOING AT OTHER SITES FOR THE NEXT FEW HOURS WITH THE EXCEPTION OF KRWL WHERE CONDITIONS LOOK TOO DRY TO PRODUCE ANYTHING MORE THAN VCSH. CONVECTION SHOULD WEAKEN AND EVENTUALLY DISSIPATE BY LATE EVENING OR AROUND MIDNIGHT. WILL NEED TO LOOK CLOSELY AT FOG POTENTIAL AGAIN AT KLAR LATER TONIGHT AS CONDITIONS LOOK VERY SIMILAR TO THIS MORNING. OTHERWISE...ANOTHER ROUND OF ISOLATED AFTERNOON AND EVENING CONVECTION IS EXPECTED AGAIN FOR TUESDAY. && .FIRE WEATHER... ISSUED AT 245 PM MDT MON JUN 23 2014 MINIMAL FIRE WEATHER CONCERNS THROUGH MIDWEEK. SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE EACH AFTERNOON AND EVENING THROUGH THURSDAY. THE COVERAGE WILL BE HIGHEST AND THE BEST CHANCE OF WETTING RAINS WILL EXIST TO THE EAST OF THE LARAMIE RANGE. TEMPERATURES WILL BEGIN TO INCREASE ON WEDNESDAY AND THURSDAY SUCH THAT MINIMUM AFTERNOON HUMIDITY VALUES WILL DROP TO AROUND 15 PERCENT WEST OF THE LARAMIE RANGE. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...FINCH LONG TERM...JAMSKI AVIATION...HAHN FIRE WEATHER...FINCH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1036 PM MDT SAT JUN 21 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 307 PM MDT SAT JUN 21 2014 STORMS HAVE DEVELOPED EARLY THIS AFTN OVER GOSHEN COUNTY AND HAVE MOVED INTO THE CENTRAL AND NORTHERN PANHANDLE. THEY HAVE STRUGGLED TO BECOME DISCRETE SO FAR DUE TO THE MARGINAL DEEP LAYER SHEAR (25-30 KTS) AND HAVE FORMED INTO LINES/CLUSTERS. SPC MESOANALYSIS SHOWS GOOD INSTABILITY WITH MLCAPES OF 1500-2000 J/KG OVER THE PANHANDLE. BELIEVE THAT THE MAIN SVR THREAT DURING THE AFTN WILL BE DAMAGING WINDS WITH THE HIGH LCLS AND DEEP BOUNDARY LAYER OVER THE PANHANDLE. LARGE HAIL IS LESS OF THE THREAT WITH THE MARGINAL DEEP LAYER SHEAR...HOWEVER MARGINALLY SVR HAIL WILL BE POSSIBLE. A SEVERE THUNDERSTORM WATCH WAS ISSUED FOR ALL OF THE NEBRASKA PANHANDLE THROUGH 03Z. ALL OF THIS STORM ACTIVITY IS OCCURING AHEAD OF A SHORTWAVE THAT IS CURRENTLY LOCATED OVER WESTERN COLORADO. THE HRRR MODEL SHOWS MOST STORMS PUSHING EAST OUT OF THE CWA BY AROUND 00Z. COLD FRONT BEHIND THE SHORTWAVE WILL PUSH ACROSS THE PLAINS LATE TONIGHT AND SUNDAY MORNING. WINDS ARE STILL NORTHERLY AT 18Z SUN AND THEN BECOME MORE NORTHEASTERLY DURING THE AFTN. MODELS HAVE DECREASED INSTABILITY A BIT OVER YESTERDAYS RUN WITH LI VALUES OF AROUND -3C IN LARAMIE/PLATTE COUNTIES AND EXTENDING EASTWARD ALONG THE COLORADO BORDER. STORMS SHOULD DEVELOP BY AFTN IN THE CONVERGENCE ALONG THE SOUTHERN LARAMIE RANGE...HOWEVER DO NOT BELIEVE THEY WILL BECOME SVR AS THEY PUSH EASTWARD. STORM COVERAGE WILL BE MORE LIMITED OVER THE PANHANDLE AS THE AIRMASS IS MORE STABLE POST FRONTAL. TEMPS WILL BE 10-15 DEGREES COOLER ON SUNDAY. FOR MONDAY SFC WINDS BECOME MORE SOUTHEASTERLY AND AIRMASS IS MORE UNSTABLE THAN SUNDAY IN AREAS NEAR THE COLORADO BORDER. THIS IS THE DAY AFTER THE FROPA...WHICH OFTEN TIMES LEADS TO A GREATER SVR THREAT. NORTHWESTERLY FLOW ALOFT IS STRONG ENOUGH...COMBINED WITH THE SOUTHEAST LLVL FLOW...TO PRODUCE 40-45 KTS OF DEEP LAYER SHEAR SO THERE WILL LIKELY BE SOME SVR POTENTIAL ON MONDAY IN AREAS ALONG INTERSTATE 80. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 307 PM MDT SAT JUN 21 2014 THE ACTIVE PATTERN WILL CONTINUE INTO NEXT WEEK AS ZONAL FLOW BECOMES MORE SOUTHWESTERLY BY THE END OF THE WEEK. BOTH THE GFS AND EURO SOLUTIONS CONTINUE TO ADVERTISE DAILY CHANCES OF AFTERNOON AND EVENING CONVECTION AS SOUTHEASTERLY LLVL RETURN FLOW PERSISTS ALL WEEK. THIS WILL RESULT IN PERSISTENT THETA-E RIDGING OVER MUCH OF THE CWFA THROUGH THE ENTIRE WEEK. TUESDAY WILL BE THE SECOND DAY POST-FRONTAL...WHICH WHEN COMBINED WITH 0-6KM SHEAR OF 40-50 KNOTS SHOULD SET THE STAGE FOR AN ACTIVE SEVERE WEATHER DAY. THE GREATEST THREAT WILL BE EAST OF THE LARAMIE RANGE. PROGD SBCAPES WILL FLARE TO BETWEEN 2000-3000 J/KG FOR WED AND THU...WHICH SHOULD BE MORE THAN ENOUGH TO COMPENSATE FOR SOMEWHAT LIGHTER VALUES OF DEEP LAYER SHEAR. WOULD EXPECT SEVERE POTENTIAL TO CONTINUE FOR BOTH WED AND THU MAINLY EAST OF THE LARAMIE RANGE AS WELL. TROUGH WILL SWING THROUGH ON FRIDAY...DRAGGING A PACIFIC FRONT THRU THE AREA WHICH WILL EFFECTIVELY SHUNT BEST INSTABILITY EAST OVER CENTRAL NEBRASKA FOR BOTH FRIDAY AND SATURDAY. AS A RESULT...EXPECT THUNDERSTORM CHANCES TO TURN MORE ISOLATED EARLY NEXT WEEKEND. TEMPERATURES WILL BE SEASONALLY PERSISTENT THROUGH THE PERIOD WITH 70S ON TUESDAY WARMING INTO THE 80S AT LOWER ELEVATIONS FOR THE REMAINDER OF THE WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY EVENING) ISSUED AT 1029 PM MDT SAT JUN 21 2014 SHOWERS AND THUNDERSTORMS SLOWLY COMING TO AN END OUT IN THE NORTHERN NEBRASKA PANHANDLE. STILL A LARGE AREA OF SHOWERS ACROSS NORTHERN WYOMING THAT WILL SAG SOUTH WITH A COLD FRONT SUNDAY. FRONT IS A LITTLE SLOWER NOW ON FORECAST MODELS THAN ORIGINALLY FORECAST...SO WE ARE LOOKING AT THIS FRONT TO MAKE IT DOWN TO THE CHEYENNE AREA PROBABLY EARLY SUNDAY MORNING AFTER 12Z. THIS WILL KEEP THE WIDESPREAD MVFR/IFR STRATUS FROM FORMING AS THE SUN WILL BE UP PRIOR TO THE FRONT MAKING IT INTO SOUTHERN WYOMING. STILL...CONVECTION SHOULD BE WIDESPREAD SUNDAY AFTERNOON AND THE PANHANDLE AIRPORTS SHOULD SEE THE BULK OF THIS CONVECTION. && .FIRE WEATHER... ISSUED AT 307 PM MDT SAT JUN 21 2014 MINIMAL FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITY VALUES WILL BE AROUND 15 PERCENT THIS AFTERNOON FOR AREAS TO THE WEST OF THE LARAMIE RANGE. WEST WINDS WILL GUST TO 20-25 MPH THROUGH EARLY EVENING. SINCE FUELS ARE STILL GREEN ENOUGH TO NOT SUPPORT FIRE GROWTH...NO CRITICAL FIRE WEATHER THREAT IS EXPECTED. COOLER TEMPERATURES ON SUNDAY THROUGH EARLY NEXT WEEK WILL CAUSE AFTERNOON HUMIDITY VALUES TO INCREASE TO THE 20-30 PERCENT RANGE FOR AREAS TO THE WEST OF THE LARAMIE RANGE. SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE EACH AFTERNOON THROUGH THE MIDDLE OF NEXT WEEK...WITH COVERAGE HIGHEST TO THE EAST OF THE LARAMIE RANGE. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...FINCH LONG TERM...HAHN AVIATION...CLAYCOMB FIRE WEATHER...FINCH
AREA FORECAST DISCUSSION
NWS ALBANY NY
500 AM EDT TUE JUN 24 2014 .SYNOPSIS... HIGH PRESSURE OFFSHORE WILL BRING SOUTHERLY WINDS WILL SLOWLY INCREASE OUR HUMIDITY. A COLD FRONT OVER THE OHIO VALLEY WILL BEGIN TO VERY SLOWLY APPROACH OUR REGION BY TONIGHT. THIS FRONT COULD TRIGGER SHOWERS AND THUNDERSTORMS MAINLY TO THE WEST OF THE CAPITAL REGION LATER TODAY. TONIGHT THROUGH EARLY THURSDAY...THE FRONT WILL SLOWLY DRAG THROUGH THE REGION...WITH WAVES OF LOW PRESSURE FORMING ALONG IT...WHICH WILL PRODUCE BOUTS OF SHOWERS AND POSSIBLE THUNDERSTORMS. ANY THUNDERSTORM COULD CONTAIN GUSTY WINDS AND HEAVY RAINFALL...ESPECIALLY WEDNESDAY AFTERNOON AND EVENING. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 500 AM EDT...SCATTERED SHOWERS HAVE WORKED INTO EXTREME NORTHERN HERKIMER AND NORTHERN HAMILTON COUNTIES. SO FAR NO CLOUD TO GROUND LIGHTNING AND THE LATEST RUC AND MSAS ANALYSIS INDICATED LITTLE OR NO INSTABILITY. SO WE WILL CALL THESE SCATTERED THROUGH EARLY MORNING. THE VAST MAJORITY OF THE REGION REMAINED DRY AND MILD AS A PERSISTENT SOUTHERLY BREEZE HAS KEPT TEMPERATURES MAINLY IN THE 60S AT THIS HOUR...WITH ONLY A FEW UPPER 50S IN THE SHELTERED MOUNTAIN VALLEYS. THROUGH SUNRISE...TEMPERATURES WILL ONLY SLOWLY FALL IF AT ALL. THE SHOWER ACTIVITY OVER OUR NORTHWESTERN ZONES SHOULD LIFT NORTHEAST...BUT THERE WERE MORE SHOWERS UPSTREAM IN LEWIS COUNTY. ASIDE FROM THE NORTHWEST CORNER...ALL OTHER AREAS OF THE FORECAST REGION WILL REMAIN DRY. A SOUTH WIND WILL CONTINUE 5 TO 15 MPH. THERE WILL A SLOW INCREASE IN THE MID LEVEL CLOUDINESS...MAINLY NORTH AND WEST OF THE CAPITAL REGION. LATER TODAY...SUNSHINE WILL BE HAPPENING FROM THE CAPITAL REGION AND TO THE SOUTHEAST DESPITE THESE INCREASING CLOUDS. A SOUTH WIND WILL INCREASE TO 10 TO 15 MPH...WITH GUSTS UP TO 25 TO PERHAPS EVEN 30 MPH AT TIMES. TEMPERATURES WILL ONCE AGAIN CLIMB WELL INTO THE 80S FROM THE CAPITAL REGION SOUTH AND EAST...WITH SOME LOCALITIES EVEN REACHING THE UPPER 80S. FURTHER NORTH AND WEST...WITH THICKER CLOUDS...TEMPERATURES WILL NOT BE QUITE AS WARM...CLOSER TO 80. DEWPOINTS WILL SLOWLY CREEP THROUGH THE 50S...REACHING 60 OR HIGHER FROM THE CAPITAL REGION AND AREAS NORTH AND WEST. INSTABILITY WILL INCREASE AND THERE WILL LIKELY BE OLD OUTFLOW BOUNDARIES ACROSS THE MOHAWK VALLEY AND SOUTHERN ADIRONDACKS. ALL OF THE FACTORS WILL INCREASE THE CHANCE OF SHOWER AND THUNDERSTORM ACTIVITY. THE 0-6KM BULK SHEAR WILL INCREASE TO ABOUT 30KTS FROM THE SOUTHWEST. THUNDERSTORM THAT DO DEVELOP COULD END UP PRODUCING SOME GUSTY WINDS (PROBABLY SUBSEVERE) BUT A ROGUE SEVERE THUNDERSTORM IS POSSIBLE WITH A BOWING SEGMENT. PWATS RAMP TO NEARLY 2 INCHES...SO ANY THUNDERSTORM COULD HEAVY RAINFALL. WE CONTINUE TO USE ENHANCED WORDING IN OUR GRIDS NORTH AND WEST OF THE CAPITAL REGION. FROM ALBANY SOUTH AND EAST...WE ONLY GAVE SLIGHT POPS (ACTUALLY NONE SOUTHEAST OF ALBANY AS RIDGING ALOFT WILL LIKELY PREVENT ANY UPWARD MOTION AND RESULTANT SHOWERS AND STORMS. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... SINCE THE COLD FRONT WILL STILL BE OUR WEST TONIGHT...THUNDERSTORM ACTIVITY THAT DOES DEVELOP LATE IN THE DAY...MIGHT ACTUALLY DIMINISH OVERNIGHT..ALTHOUGH REMNANTS OF THOSE STORMS COULD CERTAINLY MOVE FURTHER EAST. DEWPOINTS WILL CLIMB INTO THE 60S EVERYWHERE MAKING IT MUGGY NIGHT. LOWS WILL BE GENERALLY IN THE 60S...CLOSER TO 70 IN THE IMMEDIATE CAPITAL REGION. WEDNESDAY AND WEDNESDAY NIGHT...MORE ORGANIZED UPPER DYNAMICS...A LITTLE BOUNDARY LAYER WIND CORE...MUCH DEEPER MOISTURE AND SOME UPPER DIVERGENCE IS EXPECTED TO CONTRIBUTE TO AN ORGANIZED BAND OF THUNDERSTORMS AHEAD AND ALONG A COLD FRONT. INSTABILITY WILL LARGELY BE BASED AT THE SURFACE AS MIDLEVEL LAPSE RATES STILL DO NOT LOOK IMPRESSIVE. STILL ENOUGH INSTABILITY SO WE WILL HAVE TO WATCH FOR ISOLATED SEVERE WIND GUSTS...BUT MAYBE MORE OF A VERY HEAVY RAIN POTENTIAL BASED ON THE VERY ANOMALOUSLY HIGH PWAT VALUES AROUND TWO INCHES REGION WIDE. GUIDANCE HAS BETTER AGREEMENT WHERE THE AXIS OF HEAVIES RAINFALL WILL TAKE PLACE. REALLY MOST OF THE AREA LOOKS TO POTENTIALLY RECEIVE AN INCH OR BETTER OF RAINFALL. INITIALLY...NORTHERN AREAS WILL GET HIT EARLY WEDNESDAY...WITH THE AXIS SLOWLY SHIFTING SOUTH AND EAST LATE WEDNESDAY INTO EARLY THURSDAY. WE ARE STILL NOT READY TO ISSUE ANY FLASH FLOOD WATCHES YET...AS THE BULK OF THE RAIN WILL NOT FALL UNTIL LATER WEDNESDAY AND THE CONFIDENCE OF FLASH FLOODING IS BELOW 50 PERCENT DUE TO SOMEWHAT DRY CONDITIONS GOING INTO THIS EVENT. MORE ABOUT HYDROLOGICAL ISSUES CAN BE FOUND IN OUR HYDROLOGICAL SECTION. THERE ARE STILL INDICATIONS OF LINGERING UPPER ENERGY AND A LOW LEVEL FEATURE FOR ONE LAST ROUND OF LOW LEVEL FORCING AS THE COLD FRONT CONTINUES ITS PROGRESS EAST AND SOUTH. SO...LINGERING ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS THURSDAY MORNING IN MOST PLACES...BUT THROUGHOUT THE DAY IN THE MID HUDSON VALLEY AND NW CT. TEMPERATURES ON WEDNESDAY WILL HIGHLY DEPEND ON HOW CLOUDS IT REMAINS. THE 00Z NAM MOS NUMBERS WERE COOLER BASED ON MORE CLOUDS WHILE THE MAV MOS NUMBERS INDICATED PERHAPS A LITTLE MORE SUNSHINE. FOR NOW...WENT WITH THE MAV/MET MIX BUT LEANING TOWARD THE COOLER MET NUMBERS. THIS WOULD GIVE HIGHS CLOSE TO 80 AROUND THE CAPITAL REGION...LOWER TO MID 80S FURTHER SOUTH...70S WELL NORTH AND WEST. DEWPOINTS WILL BE HIGH HOLDING WELL INTO THE 60S. WEDNESDAY NIGHT LOWS WILL RANGE FROM THE UPPER 50S TO MID 60S. HIGHS THURSDAY WITH PARTIAL SUNSHINE AND ONLY WEAK COLD AIR ADVECTION WILL RANGE FROM THE MID 70S NORTHWEST TO LOWER 80S ALBANY SOUTH. && .LONG TERM /FRIDAY THROUGH MONDAY/... BEHIND THE COLD FRONT THAT EXITS THE REGION THURSDAY NIGHT...EXPECT THE ENTIRE REGION TO ENJOY SOME TRANQUIL AND DRY WEATHER FRIDAY THROUGH SUNDAY NIGHT WITH MAINLY CLEAR TO PARTLY CLOUDY SKIES. AN INCREASINGLY MOIST SOUTHWEST FLOW OF AIR COULD BRING SOME SHOWERS AND TSTMS TO THE REGION ON MONDAY. TEMPERATURES WILL BE NEAR TO SLIGHT ABOVE NORMAL FRIDAY THROUGH MONDAY. HIGHS FRIDAY AND SATURDAY WILL BE IN THE 70S TO AROUND 80. LOWS FRIDAY AND SATURDAY NIGHTS IN THE 50S TO AROUND 60. GETTING WARMER ON SUNDAY WITH HIGHS IN THE MID 70S TO LOWER 80S. LOWS SUNDAY NIGHT IN THE MID 50S TO LOWER 60S. HIGHS MONDAY IN THE UPPER 70S TO MID 80S. && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... A SLOW MOVING FRONTAL BOUNDARY WILL SLOWLY MOVE EAST FROM THE GREAT LAKES REGION ON TUESDAY. THERE WILL BE A SOUTHERLY FLOW AHEAD OF THIS SYSTEM...BUT AT THIS POINT FORECAST MODELS INDICATE THAT MOST OF THE SHOWERS/TSTMS ASSOCIATED WITH THIS FRONTAL BOUNDARY WILL REMAIN TO THE WEST OF THE TAF SITES THROUGH THE TAF PERIOD ENDING AT 06Z WEDNESDAY. AT KALB HAVE INDICATED VCSH IN THE FORECAST AFTER 23Z TUESDAY...AND AFTER 21Z AT KGFL. A BRIEF PERIOD OF VCSH HAS ALSO BEEN FORECAST FOR KGFL TUESDAY MORNING DUE TO A BATCH OF SHOWERS CURRENTLY MOVING EAST-NORTHEAST FROM LAKE ONTARIO. AT KPOU/KPSF... HAVE NOT FORECAST ANY THREAT OF PCPN. AS A RESULT...EXPECT VFR CONDITIONS AT THE TAF SITES THROUGH THE ENTIRE TAF PERIOD. WITH A SOUTHERLY FLOW OCCURRING AT ALL THE TAF SITES OVERNIGHT...AND WITH MID/HIGH CLOUDS SPREADING ACROSS THE REGION...THERE IS LITTLE CHANCE OF ANY FOG FORMATION TONIGHT AND HAVE NOT FORECAST ANY. SOUTH WINDS AT KGFL/KPSF/KPOU OVERNIGHT WILL GENERALLY BE 8 KTS OR LESS...BUT AT KALB THE SPEEDS WILL BE 10 TO 15 KTS WITH GUSTS OF AROUND 20 KTS. WIND SPEEDS WILL INCREASE AT ALL THE TAF SITES ON TUESDAY TO 10 TO 15 KTS WITH GUSTS OF 16 TO 22 KTS. WIND SPEEDS WILL DECREASE TO 5 TO 10 KTS TUESDAY NIGHT...WITH SOME GUSTS OVER 15 KTS AT KALB. OUTLOOK... TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHC SHRA...TSRA. WEDNESDAY: HIGH OPERATIONAL IMPACT. LIKELY SHRA...TSRA. WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY SHRA...TSRA. THURSDAY: LOW OPERATIONAL IMPACT. ISOLATED SHRA...TSRA. THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... MAINLY DRY TODAY OUTSIDE OF THE ADIRONDACKS AND MOHAWK VALLEY WHERE SCATTERED SHOWERS AND POSSIBLE THUNDERSTORMS WILL TAKE PLACE. AFTERNOON RH VALUES WILL RANGE FROM AROUND 40 FROM ALBANY SOUTH AND EAST...BUT WILL REMAIN IN THE 50-60 PERCENT RANGE FURTHER NORTH AND WEST WHERE SHOWERS AND STORMS ARE MORE POSSIBLE. A GUSTY SOUTH WIND WILL BE 10 TO 20 MPH. A WET AND UNSETTLED PERIOD EXPECTED TONIGHT THROUGH EARLY THURSDAY. RH VALUES SHOULD INCREASE BACK TO NEAR 100 PERCENT TUESDAY NIGHT WITH SHOWERS AND THUNDERSTORMS. ON WEDNESDAY...MOST AREAS SHOULD SEE SHOWERS AND THUNDERSTORMS AND RH VALUES WILL ONLY DROP TO THE 60 TO 80 PERCENT RANGE. ALL AREAS ARE EXPECTED TO RECEIVE A QUARTER INCH OR MORE OF RAINFALL. A DRYING TREND EXPECTED LATER THURSDAY INTO THE WEEKEND. && .HYDROLOGY... SCATTERED SHOWERS AND THUNDERSTORMS MAINLY ACROSS THE ADIRONDACKS AND MOHAWK VALLEY TODAY. SOME OF THESE COULD PRODUCE LOCALLY HEAVY RAINFALL RESULTING WITH SOME PONDING OF WATER. ONLY AN OUTSIDE OF SHOWER OR THUNDERSTORM IS EXPECTED FURTHER SOUTH AND EAST. AS A SLOW MOVING COLD FRONT APPROACHES TOMORROW...AND ONE...IF NOT SEVERAL WAVES OF LOW PRESSURE DEVELOP ALONG IT...SHOWER AND THUNDERSTORM CHANCES INCREASE...TO LIKELY BY LATE TUESDAY NIGHT IN THE WESTERN MOHAWK VALLEY AND SOUTHERN ADIRONDACKS AND SCATTERED EVERYWHERE ELSE. BY WEDNESDAY...SHOWERS AND THUNDERSTORMS ARE LIKELY ACROSS THE REGION. SOME OF THE STORMS COULD PRODUCE LOCALLY HEAVY WITH POTENTIAL FOR PONDING OF WATER. WE ARE FORECASTING AN AVERAGE BASIN RAINFALL OF 1-2 INCHES OF RAINFALL ACROSS OUR FORECAST AREA. THIS COULD BE ENOUGH RAINFALL TO PRODUCE SOME SIGNIFICANT WITHIN BANK RISES ON SOME RIVERS AND STREAMS. A COUPLE SPOTS LIKE DELTA DAM AND UTICA COULD REACH ACTION STAGE. TRAINING THUNDERSTORMS CONTAINING HEAVY RAINFALL DO HAVE THE REMOTE POSSIBILITY OF PRODUCING FLASH FLOODING BUT RIGHT NOW...THE THREAT OF THAT WAS LOWER THAN 50 PERCENT SO NO FLASH FLASH FLOOD WATCHES WERE ISSUED ON THIS SHIFT. KEEP IN MIND ANY THUNDERSTORM COULD PRODUCE LOCAL AMOUNTS WELL OVER 2 INCHES. STAY TUNED. DRIER WEATHER WILL TAKE HOLD LATER THURSDAY INTO THE WEEKEND. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...HWJIV NEAR TERM...HWJIV/NAS SHORT TERM...HWJIV/NAS LONG TERM...GJM AVIATION...GJM FIRE WEATHER...HWJIV HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS TOPEKA KS
350 AM CDT Tue Jun 24 2014 .SHORT TERM...(Today and Tonight) Issued at 327 AM CDT TUE JUN 24 2014 Quiet weather was in place across the local forecast area early this morning with light winds, high clouds, and departing surface high pressure. Farther to the west in western KS and eastern CO, a loosely organized convective system was making slow eastward progression. This convection seemed tied to a weak upper disturbance that was making a very slow eastward progression out of CO and NM through weak flow aloft. Additional weak, but seemingly more well-defined upper waves were located over southern California and eastern Montana. While the CA wave will be slow to move east, it seems that the Montana system may dive southeast and possibly interact with the system in eastern Colorado by tonight. In terms of the local forecast and sensible weather through tonight, expect the area of showers and thunderstorms to continue with slow but steady eastward development. Generally speaking, the NMM, ARW, and HRRR seem to be handling the situation well through the day, which coincides fairly well with larger scale model guidance as well. This suggests that showers and a few storms may encroach upon the Highway 81 corridor by early afternoon and possibly build into far eastern KS by early evening. All indications suggest a tight instability gradient from east to west which also gradually progresses to the east with time. This should prevent the convection from developing more quickly east today even if a few cold pools push out from convection. As the instability does arrive, it will be rather meager, as will wind shear profiles, and even strong storms seem quite unlikely through tonight. All told, much of the area stands a good chance to see at least some precip by sunrise on Wednesday, although amounts may be spotty. Aside from precip, temperatures will be in the lower to middle 80s today, with some question in just how warm it will get depending largely on cloud cover as more widespread clouds could hold everyone in the lower 80s. Winds will be light through tonight and dewpoints will remain fairly comfortable...in the low to middle 60s. .LONG TERM...(Wednesday through Monday) Issued at 327 AM CDT TUE JUN 24 2014 A slow upper shortwave trough translates southeast over the CO Rockies and central plains on Wednesday afternoon. Position and timing from guidance was fairly similar in developing a swath of showers and thunderstorms across the CWA from the overnight into the afternoon hours. Ample southerly moisture transport is aided by PWAT values in excess of 1.6 inches through the period. Have increased chances across the area during the day, gradually tapering off west to east by Wednesday evening. Do not expect severe storms with main threat being heavy rain and flash flooding. Occasional showers and thunderstorms are expected from Thursday onward as weaker upper perturbations within the mean flow give much uncertainty where mesoscale boundaries or areas of lift are positioned for scattered convection to form. Similar to previous trends, late afternoon into early evening time frame during peak heating and minimal inhibition is likely. The weekend forecast, for the most part, appears dry Friday and Saturday with temporary ridging over the area. On Saturday, H5 flow begins to back and increase toward the southwest in response to a deepening upper trof across the western CONUS. By the late afternoon period, a moist and unstable airmass in place may trigger scattered thunderstorms along/ahead of a cold front stretched over central KS into south central NE. A few storms may be severe in proximity to the convergent boundary where surface based CAPE in excess of 3000 J/KG complements effective shear near 40 kts. Activity weakens as it progresses eastward by Sunday with some indication of redevelopment by late afternoon across east central areas. Otherwise trends from the GFS/ECMWF depict weak trofs rotating through the main wave as the frontal boundary becomes a focal point for additional scattered convection Sunday evening into Monday. Minor adjustments were made to temperatures in the extended. Insulation from cloud cover and rainfall Wednesday should hold highs to the low 80s throughout the afternoon. Sunshine returns Thursday as consensus guidance warrants increased highs in the mid and upper 80s. With ample sunshine and increased boundary layer mixing through the weekend, warming trend continues with highs in the upper 80s to low 90s by Monday. Overnight lows follow suit from the mid 60s Thursday to the low 70s Friday into Monday. && .AVIATION...(For the 06Z TAFs through 06Z Tuesday Night) Issued at 1131 PM CDT MON JUN 23 2014 Previous thinking was that the recent rains, light winds, and clear skies was going to cause ground fog or haze later this morning, but increasing clouds from the convection out west might inhibit this development. There is probably still a slight chance of haze at TOP and MHK, but vis should remain VFR or perhaps briefly drop to MVFR depending on the cloud coverage. There is a chance non-severe thunderstorms could reach MHK after 00Z although the confidence on coverage and timing is low at this point. Thunderstorms may also reach TOP/FOE very late in the taf period. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Barjenbruch LONG TERM...Bowen AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
335 AM CDT Tue Jun 24 2014 ...Updated Short Term Section... .SHORT TERM...(Today and tonight) ISSUED AT 329 AM CDT TUE JUN 24 2014 At the time of this writing (just after 0830 UTC), a small mesoscale convective system (MCS) was slowly dissolving as it moved east-southeast across southwestern Kansas. There were other weakly organized storms across northwestern Kansas. There appeared to be a slow warming in infrared cold cloud tops associated with the western Kansas convection as we head toward the early morning hours. Water vapor and RAP analysis suggested a weak shortwave trough from southern Wyoming down into central Colorado. This feature will allow the redevelopment of the southeastern Colorado leeside low with south-southeast winds resuming by mid to late morning across portions of southwestern Kansas. Winds in the wake of this morning`s MCS will be light and one or two convergence zones will likely set up at the surface where south to southeast winds of 12 to 15 knots will converge into areas of weak or nearly calm winds over portions of west central and/or northwestern Kansas. These convergence areas at the surface will foster development of surface-based thunderstorms in the 20-22Z time frame just about anywhere across far east-central/southeast Colorado and/or western Kansas. The NAM12 shows a band of enhanced mid level flow from the west-northwest across eastern Colorado and western Kansas of 28 to 34 knots (500mb)...providing ample enough deep layer shear for supercell structures with the strongest discrete convection. Any supercell storms which develop would move almost due south given the mid level flow direction out of the west-northwest. It is unclear how long discrete thunderstorm phase will last, but back on Sunday there was a supercell storm that rolled south for 4+ hours (eastern Oklahoma Panhandle into the northeastern Texas Panhandle) before becoming absorbed by other convection and transitioning to an MCS. The CAPE/Shear profile does not look all that dissimilar from the Sunday event. Should a supercell storm form and thrive in this environment, maximum hail size of tennis balls will be possible (local research /Large Hail Parameter/ in the upper single digits also supports this maximum hail size). The thinking is that any such hail event of that size would be very isolated and probably brief with many of the hail reports being half dollar to 2-inch in diameter. We increased POPs to 60 percent and included "Heavy Rain" in the grids given the continued very moist environment and impressive QPF signals from the WRF high- resolution models...as well as the ECMWF. POPs may need to be increased further (to categorical/80+) later on today as mesoscale details emerge. .LONG TERM...(Wednesday through Monday) ISSUED AT 326 AM CDT TUE JUN 24 2014 A weak upper level ridge is progged to move through the Rockies Wednesday, then through the Plains Thursday before exiting stage right on Friday. Meanwhile, an upper level long wave trough is expected to move into the Pacific Northwest and Intermountain West Wednesday and Thursday then into the Northern Rockies and Northern Plains Friday into this weekend. A trough of low pressure at the surface will intensify across eastern Colorado as this feature approaches bringing southerly winds to western Kansas through the weekend. An exiting MCS may bring scattered thunderstorms to south central Kansas Wednesday morning but should exit the area by noon. A slight chance of thunderstorms will be possible late Wednesday afternoon into Wednesday night, otherwise expect mostly cloudy skies. Clouds decrease in coverage Thursday with partly cloudy skies expected through Saturday. A chance of thunderstorms will then be possible across northern Kansas and the I-70 corridor Saturday night as lift increases due to an upper level shortwave moving through across Nebraska. Otherwise expect a slight increase in cloud cover. Upper level ridging looks to build into the southern Rockies by the beginning of next week. This should suppress any significant weather across western Kansas with partly cloudy skies. Highs throughout the extended period start out in the upper 80s Wednesday with lower 90s expected Thursday through the weekend. Highs in the mid to upper 90s are possible early next week. Lows start out in the upper 60s Thursday morning with lower 70s anticipated through early next week. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) ISSUED AT 123 AM CDT TUE JUN 24 2014 A small mesoscale convective system (MCS) will affect GCK and DDC terminals through 08Z, but otherwise VFR conditions will prevail with light winds overnight. Numerous thunderstorms are expected to develop by mid afternoon across much of west-central and southwest Kansas, and in the TAF will forecast a 6-hr period of PROB30 thunderstorms for DDC, GCK, HYS 21Z to 03Z. && .PRELIMINARY POINT TEMPS/POPS... DDC 85 65 87 67 / 60 60 20 30 GCK 85 64 87 67 / 60 60 20 30 EHA 84 64 90 66 / 60 50 20 30 LBL 87 64 90 68 / 60 60 20 30 HYS 80 64 85 67 / 40 40 20 30 P28 86 68 87 69 / 40 60 30 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Hovorka_42 AVIATION...Umscheid
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
327 AM CDT Tue Jun 24 2014 ...Updated long term section... .SHORT TERM...(This evening through Tuesday) ISSUED AT 300 PM CDT MON JUN 23 2014 Another MCS night likely across far western Kansas. There is isolated weak thunderstorms developing across south central Kansas this afternoon as well. Have the highest pops along and west of Garden City to Liberal, although the most recent HRRR propagates the MCS farther east. Something to watch and update ESTF grids based on reality rather than model output solutions. There could be some severe weather across far western Kansas as meso analyzed SBCAPES are near 2000 J/kg and 30 kt effective bulk shear. Most probable threat is hail and winds along with heavy rainfall as pwats remain just below the 75th percentile for a normal distribution. Overnight minimums will be in the 60sF. Another MCS likely tomorrow. Attempted to add some diurnal pop variability with a minimum towards 18Z and maximum at the end of my period. Some uncertainty in storm placement as convective allowing models are different than the global models. Broad bushed pops at this point as pwats remain high and the overall synoptic pattern is that which is conducive for MCS`s. There could be some marginal severe weather again as instability is moderate and bulk shear is more marginal. Highs in the 80sF. .LONG TERM...(Wednesday through Monday) ISSUED AT 326 AM CDT TUE JUN 24 2014 A weak upper level ridge is progged to move through the Rockies Wednesday, then through the Plains Thursday before exiting stage right on Friday. Meanwhile, an upper level long wave trough is expected to move into the Pacific Northwest and Intermountain West Wednesday and Thursday then into the Northern Rockies and Northern Plains Friday into this weekend. A trough of low pressure at the surface will intensify across eastern Colorado as this feature approaches bringing southerly winds to western Kansas through the weekend. An exiting MCS may bring scattered thunderstorms to south central Kansas Wednesday morning but should exit the area by noon. A slight chance of thunderstorms will be possible late Wednesday afternoon into Wednesday night, otherwise expect mostly cloudy skies. Clouds decrease in coverage Thursday with partly cloudy skies expected through Saturday. A chance of thunderstorms will then be possible across northern Kansas and the I-70 corridor Saturday night as lift increases due to an upper level shortwave moving through across Nebraska. Otherwise expect a slight increase in cloud cover. Upper level ridging looks to build into the southern Rockies by the beginning of next week. This should suppress any significant weather across western Kansas with partly cloudy skies. Highs throughout the extended period start out in the upper 80s Wednesday with lower 90s expected Thursday through the weekend. Highs in the mid to upper 90s are possible early next week. Lows start out in the upper 60s Thursday morning with lower 70s anticipated through early next week. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) ISSUED AT 123 AM CDT TUE JUN 24 2014 A small mesoscale convective system (MCS) will affect GCK and DDC terminals through 08Z, but otherwise VFR conditions will prevail with light winds overnight. Numerous thunderstorms are expected to develop by mid afternoon across much of west-central and southwest Kansas, and in the TAF will forecast a 6-hr period of PROB30 thunderstorms for DDC, GCK, HYS 21Z to 03Z. && .PRELIMINARY POINT TEMPS/POPS... DDC 85 65 87 67 / 40 50 20 30 GCK 85 64 87 67 / 40 50 20 30 EHA 84 64 90 66 / 40 50 20 30 LBL 87 64 90 68 / 40 50 20 30 HYS 82 64 85 67 / 20 40 20 30 P28 86 68 87 69 / 30 40 30 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Sugden LONG TERM...Hovorka_42 AVIATION...Umscheid
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
125 AM CDT Tue Jun 24 2014 ...Updated aviation section... .SHORT TERM...(This evening through Tuesday) ISSUED AT 300 PM CDT MON JUN 23 2014 Another MCS night likely across far western Kansas. There is isolated weak thunderstorms developing across south central Kansas this afternoon as well. Have the highest pops along and west of Garden City to Liberal, although the most recent HRRR propagates the MCS farther east. Something to watch and update ESTF grids based on reality rather than model output solutions. There could be some severe weather across far western Kansas as meso analyzed SBCAPES are near 2000 J/kg and 30 kt effective bulk shear. Most probable threat is hail and winds along with heavy rainfall as pwats remain just below the 75th percentile for a normal distribution. Overnight minimums will be in the 60sF. Another MCS likely tomorrow. Attempted to add some diurnal pop variability with a minimum towards 18Z and maximum at the end of my period. Some uncertainty in storm placement as convective allowing models are different than the global models. Broad bushed pops at this point as pwats remain high and the overall synoptic pattern is that which is conducive for MCS`s. There could be some marginal severe weather again as instability is moderate and bulk shear is more marginal. Highs in the 80sF. .LONG TERM...(Tuesday night through Monday) ISSUED AT 344 PM CDT MON JUN 23 2014 For Tuesday night, a weak upper level shortwave trough will be moving across western Kansas with numerous showers and thunderstorms expected as an MCS. At this time with weak wind shear and instability the chances for severe do not look that promising. Have upped precip chances. Overnight lows will be in the mid 60s. On Wednesday, more widely scattered thunderstorms are possible with moderate instability mainly by late afternoon. The upper level winds again look weak with severe thunderstorms not a good bet. Highs will be in the mid to upper 80s. For the period Thursday into next Monday, the best chance for more scattered thunderstorms looks to be on Thursday with another weak upper level wave. A stronger wave moves from the Pacific Northwest and into the Northern Plains by the Weekend with the best chance for thunderstorms mainly far north across I-70. Lows will be mild in the upper 60s to lower 70s, with highs warming slowly from the upper 80s into the low to mid 90s by the Weekend. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) ISSUED AT 123 AM CDT TUE JUN 24 2014 A small mesoscale convective system (MCS) will affect GCK and DDC terminals through 08Z, but otherwise VFR conditions will prevail with light winds overnight. Numerous thunderstorms are expected to develop by mid afternoon across much of west-central and southwest Kansas, and in the TAF will forecast a 6-hr period of PROB30 thunderstorms for DDC, GCK, HYS 21Z to 03Z. && .PRELIMINARY POINT TEMPS/POPS... DDC 85 65 87 67 / 40 50 20 30 GCK 85 64 87 67 / 40 50 20 30 EHA 84 64 90 66 / 40 50 30 30 LBL 87 64 90 68 / 40 50 30 30 HYS 82 64 85 67 / 20 40 20 30 P28 86 68 87 69 / 30 40 30 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Sugden LONG TERM...Kruse AVIATION...Umscheid
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
403 AM EDT TUE JUN 24 2014 .SHORT TERM... TODAY AND TONIGHT COMPARED TO YESTERDAY...THE LARGER SCALE WEATHER FEATURES HAVE BECOME MORE ORGANIZED IF NOT STRONGER IN MAGNITUDE. THE RESULT WILL BE A WET DAY AROUND SE MICHIGAN. EXPECT SHOWERS AND THUNDERSTORMS TO BECOME WIDESPREAD DURING THE MORNING AND LAST THROUGH EARLY EVENING BEFORE DRIFTING EASTWARD OUT OF THE AREA. THE REST OF TONIGHT WILL BE CONCERNED WITH THE PROGRESS OF A TRAILING COLD FRONT THAT WILL MOVE THROUGH THE OHIO BORDER BY SUNRISE WEDNESDAY. SATELLITE IMAGERY AND MODEL ANALYSIS FIELDS INDICATE A WELL-DEFINED UPPER LEVEL TROUGH MOVING THROUGH THE MIDWEST AND MISSISSIPPI VALLEY DURING THE EARLY MORNING. THERE IS ALSO A DISTINCT JET MAX OVER THE GREAT LAKES WHERE THE TROUGH IS PHASING WITH THE NORTHERN STREAM CANADIAN TROUGH/LOW. THE ENTRANCE REGION OF THIS JET IS SETTING UP TO SUPPORT ENHANCED LIFT ALONG AND EAST OF THE TROUGH AXIS FROM THE MID MISSISSIPPI VALLEY INTO THE SOUTHERN GREAT LAKES. THESE UPPER LEVEL FEATURES ARE WELL-ALIGNED WITH THE SURFACE TROUGH AND LOW TO MID LEVEL MOISTURE AXIS CONSISTING OF 850 MB DEWPOINT AROUND 13C, 700 MB DEWPOINT AROUND 5C, AND PRECIPITABLE WATER APPROACHING 2 INCHES. THE RESULT IS A BROAD AREA OF SHOWERS AND THUNDERSTORMS FROM ARKANSAS INTO SOUTHERN LAKE MICHIGAN AT PRESS TIME WHICH WILL EXPAND NORTHEASTWARD THROUGH THE REST OF LOWER MICHIGAN DURING THE MORNING AND PERSIST THROUGH THE AFTERNOON. THE 00Z MODELS COLLECTIVELY HAVE A GOOD HANDLE ON THE BULK MASS AND MOISTURE FIELDS...BUT THE NAM AND RECENT RUNS OF THE RAP ARE MORE THAN A SERVICEABLE REPRESENTATION OF THE SW-NE ORIENTED BAND OF CONVECTION SETTING UP PARALLEL TO THE UPPER FLOW. FORECAST SOUNDINGS FROM THE NAM THROUGH BUFKIT ANALYSIS INDICATE MBE VECTORS ALIGNED WITH THE MEAN FLOW...WHICH IS A HEAVY RAINFALL SIGNATURE...BUT HIGH-RES RUNS OF THE HRRR AND WRF-NMM ARE MORE PROGRESSIVE AS IS THE LARGER SCALE PATTERN IN THE GFS AND ECMWF. THIS IS ENOUGH EVIDENCE TO HOLD OFF ON FLOOD HEADLINES FOR NOW BUT PLAN TO HIGHLIGHT HEAVY RAINFALL IN THE FORECAST WITH THE EXPECTATION OF 1-2 INCH TOTALS AND LOCALLY HIGHER AMOUNTS THROUGH THE DAY...MAINLY OVER THE SOUTH HALF OF SE MICHIGAN. THE SOUTHERN STREAM UPPER TROUGH WILL SLIDE EASTWARD TONIGHT AND TAKE THE RAIN SHIELD OUT OF SE MICHIGAN BY MID EVENING. THAT WILL LEAVE THE NORTHERN STREAM UPPER TROUGH/LOW TO PIVOT SOUTHWARD DURING THE REST OF THE NIGHT. SUBSIDENCE IN BETWEEN THESE TWO FEATURES WILL HELP DRY THINGS OUT FROM A RAINFALL PERSPECTIVE BUT BOUNDARY LAYER MOISTURE WILL REMAIN HIGH WITH WEAK GRADIENT FLOW SUPPORTING BOTH LOW CLOUDS AND FOG DURING THE OVERNIGHT HOURS. THE ASSOCIATED COLD FRONT WILL BRING A WIND SHIFT TO THE NORTHEAST IN THE SAGINAW VALLEY SHORTLY AFTER MIDNIGHT WHICH WILL PROGRESS SOUTHWARD DURING THE NIGHT BUT LOW LEVEL DRY ADVECTION WILL BE SLOW UNTIL AFTER SUNRISE. && .LONG TERM...WEDNESDAY THROUGH SUNDAY THE PSEUDO ZONAL UPPER LEVEL JET AXIS WILL BE IN THE PROCESS OF EXITING THE REGION ON WEDNESDAY. SOME FAIRLY BIG CHANGES IN THE MODEL GUIDANCE COMPARED TO 24 HOURS AGO. NWP IS NOW MORE UNIFORM/LESS NOISY IN BRINGING THE UPPER LEVEL DISTURBANCE OVER THE DAKOTAS DIRECTLY INTO LOWER MICHIGAN FOR THE AFTERNOON. IN ADDITION...ANOTHER FAVORABLE ZONE OF RIGHT ENTRANCE REGION DYNAMICS ARE EXPECTED TO SET UP SHOP OVER SOUTHEASTERN MICHIGAN WITH JET ENERGY THAT IS ASSOCIATED WITH THE AFOREMENTIONED UPPER LEVEL VORTICITY MAXIMUM. THIS CONCURRENT FORCING SHOULD ALWAYS GIVE ONE PAUSE AND CERTAINLY DOES HERE TOO. THE PROBLEM IS THE FORECASTED THERMODYNAMIC PROFILE IS EXPECTED TO BE STABLE WITH A SUBSIDENCE INVERSION CENTERED BETWEEN 700-600MB. THERE IS THE POTENTIAL TO BYPASS THIS FEATURE...WHICH WILL REQUIRE A HIGH AMOUNT OF BOUNDARY LAYER MOISTURE. NAM IS SUPPORTIVE OF THIS...BUT WITH IT/S HIGH BIAS IT/S NOT EXACTLY A STRONG ENDORSEMENT. WILL CONTINUE TO GO DRY HERE...AS THIS LOOKS LIKE A CALL FOR THE SHORT TERM. HIGH TEMPERATURES ARE EXPECTED TO RANGE IN THE 70S NORTH...TO NEAR 80 FOR THE HIGH SFC PRESSURE AREAS SOUTH AND EAST OF THE GLACIAL RIDGE. STRONG MID TO UPPER LEVEL GEOPOTENTIAL HEIGHT RISES WILL THEN LEAD TO STRONG SURFACE HIGH PRESSURE FOR THE END OF THE WEEK. NWP SIGNAL IN THE MODEL OUTPUT SUGGESTS THERE WILL ALSO BE A HEAVY COMPONENT FROM THE STABLE LAKE AGGREGATE. DRY WEATHER WITH A MODERATING AIRMASS SHOULD LEAD TO VERY FAVORABLE WEATHER CONDITIONS. AN EASTERLY FLOW TRAJECTORY SEEMS TO BE PLAYING SOME HAVOC WITH FORECASTED SFC TEMPERATURES...BUT READINGS SHOULD PUSH 80 DEGREES THURSDAY AND EXCEED 80 DEGREES BY FRIDAY. && .MARINE... ACTIVE STRETCH OF WEATHER WILL PERSIST INTO MID WEEK FOR THE EASTERN GREAT LAKES AS A PAIR OF FRONTS WORK THROUGH THE AREA. THE FIRST FRONT IS DRAPED ALONG A LINE FROM LAKE ONTARIO AND LAKE ERIE...SOUTHWEST INTO THE OHIO VALLEY AND WILL PRODUCE SHOWERS AND THUNDERSTORMS THROUGH THIS AFTERNOON. THIS WILL VEER WINDS FROM SOUTHERLY TO WESTERLY. A SECOND COLD FRONT WILL DROP SOUTHWARD OUT OF CANADA THROUGH THE CENTRAL GREAT LAKES TONIGHT WEDNESDAY...USHERING MODEST NORTHERLY WINDS DOWN THROUGH LAKE HURON. A WEAK PRESSURE GRADIENT WILL KEEP WINDS LIGHT THROUGH THE PERIOD...GENERALLY LESS THAN 15 KNOTS...WHICH IN TURN WILL KEEP WAVE HEIGHTS IN CHECK. && .AVIATION...ISSUED 1150 PM EDT MON JUN 23 2014 //DISCUSSION... SHRAS AND A FEW TSRAS WILL LIFT NORTH OF TERMINALS OVERNIGHT WITH WARM FRONTAL BOUNDARY. HOWEVER...ADDITIONAL ACTIVITY WILL SPREAD INTO THE AREA TUESDAY MORNING AS LOW PRESSURE LIFTS INTO THE NORTHERN GREAT LAKES AND COLD FRONT MOVES INTO THE AREA. WILL LIMIT TEMPO GROUPS TO 08Z SOUTH...10Z NORTH AND BRING SHRAS/TSRAS BACK IN THE 14Z-15Z TIME FRAME AS FORCING FROM APPROACHING COLD FRONT COINCIDES WITH INCREASING BROADSCALE LIFT AS SHORTWAVE LIFTS NORTHEAST INTO AREA ALONG THE BOUNDARY FROM THE SOUTHERN MISSISSIPPI VALLEY. CLEARING WILL THEN ENSUE LATE IN THE FORECAST AS THIS MAIN UPPER LEVEL TROUGH AXIS PROGRESSES EAST OF TH REGION. //DTW THRESHOLD THREATS... * MEDIUM CONFIDENCE IN CEILINGS BELOW 5KFT BY TUESDAY MORNING. * MEDIUM CONFIDENCE IN THUNDERSTORMS AFFECTING KDTW TUESDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ SHORT TERM...BT LONG TERM....CB MARINE.......CB AVIATION.....DG YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS HASTINGS NE
402 AM CDT TUE JUN 24 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 405 AM CDT TUE JUN 24 2014 MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND TEMPERATURES. CURRENT SURFACE ANALYSIS HAS A RIDGE OF HIGH PRESSURE ACROSS THE AREA EARLY THIS MORNING. SURROUNDING RADARS SHOW SHOWERS AND THUNDERSTORMS ON THE HIGH PLAINS GRADUALLY MOVING TOWARDS THE EAST. THE SURFACE HIGH IS EXPECTED TO MOVE OFF TO THE EAST. AN UPPER LEVEL WAVE IS EXPECTED TO MOVE INTO THE AREA DURING THE DAY. EXPECT THE CURRENT PRECIPITATION TO CONTINUE TO MOVE TO THE EAST AND INTO THE AREA BY DAYLIGHT. THE THUNDERSTORMS WILL CONTINUE TO MOVE ACROSS THE AREA DURING THE MORNING HOURS AND INTO THE AFTERNOON. THE HRRR AND THE 4KM WRF BOTH HAVE THE MAIN BAND OF THUNDERSTORMS MAINLY THROUGH THE FORECAST AREA BY MID AFTERNOON. THE MAIN DIFFERENCE IS THAT THE HRRR BRINGS IN ANOTHER BAND LATER THIS AFTERNOON. HAVE KEPT CHANCES IN DURING THE LATE AFTERNOON AND INTO THE NIGHT TIME HOURS. SEVERAL TIMES LATELY THERE HAVE BEEN MORE THUNDERSTORMS THAT DEVELOP ON THE HIGH PLAINS DURING THE AFTERNOON. THE THUNDERSTORMS MOVE INTO THE FORECAST AREA LATE EVENING AND OVERNIGHT. THE MUCAPE IS BEST DURING THE AFTERNOON BUT A LITTLE REMAINS THROUGH THE NIGHT. EXPECT THERE COULD BE A STRONG STORM OR TWO AROUND THE AREA THIS AFTERNOON AND EVENING...THEN TURN INTO A RAIN EVENT DURING THE NIGHT TIME HOURS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 405 AM CDT TUE JUN 24 2014 THE BIGGEST CHALLENGE WILL BE DETERMINING CHANCES OF RAIN IN THE LONG TERM. THE ZONAL FLOW WILL GRADUALLY BECOME MORE SOUTHWEST AS AN UPPER LEVEL TROUGH MOVES INTO THE WESTERN UNITED STATE. THIS WILL HELP KICK UP PULSES OF ENERGY INTO THE HIGH/GREAT PLAINS THAT WILL GIVE US A SHOT A SHOWER/THUNDERSTORMS FOR MOST PERIODS OF THE LONG TERM. THE GREATEST CHANCE OF RAIN WILL BE FRIDAY NIGHT AS A WARM FRONT MOVES IN AND THROUGH THE AREA...ALONG WITH AN INCREASED LOW- LEVEL JET AND POTENTIAL STRONG CONVERGENCE NEAR THE NOSE OF THE JET NEARBY. STRONG TO SEVERE STORMS CAN NOT BE RULED OUT...JUDGING BY SEVERE PARAMETERS...FOR MUCH OF THE LONG TERM...BUT NARROWING DOWN A DAY THAT IT WOULD BE MORE LIKELY IS TOO DIFFICULT TO IDENTIFY NOW. TEMPERATURES APPEARED TO BE PRETTY MUCH ON TRACK FROM THE PREVIOUS FORECAST...SO NO MAJOR CHANGES TO TEMPERATURES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1217 AM CDT TUE JUN 24 2014 MAIN CONCERNS FOR THE FORECAST WILL BE THUNDERSTORM CHANCES. MODELS ARE SUGGESTING THAT SHOWERS AND THUNDERSTORMS WILL MOVE THROUGH THE TERMINAL AREA LATE THIS MORNING THROUGH THE AFTERNOON. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...JCB LONG TERM...HEINLEIN AVIATION...JCB
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
337 AM MDT TUE JUN 24 2014 .SYNOPSIS... AN ACTIVE WEATHER PATTERN WILL CONTINUE MAINLY FROM THE CENTRAL MOUNTAIN CHAIN EAST TO THE TEXAS BORDER. THIS INCLUDES THE POTENTIAL FOR STRONG TO SEVERE THUNDERSTORMS ACROSS PARTS OF THE EAST WITH THE FOCUS FOR SEVERE WEATHER SHIFTING TO THE NORTHEAST PLAINS LATER TODAY INTO EVENING. AFTER TONIGHT... A GRADUAL DRYING TREND IS EXPECTED FOR MID TO LATE WEEK WITH A MOSTLY DRY FORECAST FOR THURSDAY THROUGH SUNDAY. WE CANNOT RULE OUT ISOLATED THUNDERSTORMS FOR THE NORTHERN MOUNTAINS OR FAR EASTERN PLAINS FOR THE SECOND HALF OF THE WEEK...BUT HOTTER AND DRIER CONDITIONS WILL PREDOMINATE. && .DISCUSSION... MONITORING STRONG TO SEVERE CONVECTION ACROSS PARTS OF THE NORTHEAST AND EAST CENTRAL PLAINS EARLY THIS MORNING. EARLY STAGES OF A DEVELOPING MESOSCALE CONVECTIVE COMPLEX UNDERWAY NORTHWEST OF TUCUMCARI THAT IS SIMILAR TO WHAT THE LATEST 13KM RAP AND 03Z HRRR ADVERTISED IF NOT A LITTLE FARTHER SOUTH. SHALLOW SHORTWAVE TROUGH TRANSLATING EASTWARD COUPLED WITH A BROAD REGION OF UPPER LEVEL DIFLUENCE AIDING THIS EARLY MORNING DEVELOPMENT THAT IS ALIGNED ALONG A NW-SE ORIENTED SURFACE BOUNDARY WITH A STRONG/WELL- DEFINED MOISTURE/INSTABILITY GRADIENT STRETCHING FROM NORTH OF SANTA ROSA SEWD TOWARD THE LUBBOCK AREA. MADE SOME ADJUSTMENTS TO POP/WX GRIDS BUT WILL LIKELY REVISIT JUST BEFORE PUBLISHING. TRENDS AFTER THIS MORNING/S CONVECTIVE COMPLEX WEAKENS AND/OR EXITS TO THE EAST BETWEEN 13Z-15Z WILL BE MORE COMPLICATED... AS WESTWARD-PUSHING OUTFLOW BOUNDARIES MAY REINFORCE LOW LEVEL MOISTURE FIELDS A BIT FARTHER WEST THAN PREVIOUSLY EXPECTED. REGARDLESS... ANY LOW LEVEL MOISTURE WEST OF THE CENTRAL MOUNTAIN CHAIN WILL REMAIN QUITE SHALLOW AND WITH MID- LEVEL DRYING AND SOME LARGE-SCALE SUBSIDENCE DO NOT ANTICIPATE ANY NEED FOR EXPANSION OF ISOLATED POPS EAST OF THE DIVIDE THE RIO GRANDE. DID BEEF UP POPS FOR SC AREAS AS WELL AS THE FAR NE WHERE LOW LEVEL WINDS MAY GRADUALLY BACK TO MORE EASTERLY LATE IN THE DAY INCREASING POTENTIAL FOR SEVERE THERE. LESS ACTIVE TONIGHT INTO WED AM AS MID-LEVEL DRYING ADVANCES EASTWARD BENEATH A GENERAL WESTERLY FLOW REGIME WITH LESS DEFINED INDICATORS FOR LARGE SCALE UPWARD FORCING. EXPECT TO SEE A FAIRLY WELL DEFINED SURFACE DRYLINE WED PM NEAR THE NM/TX LINE WITH A DEEPENING SURFACE LOW OVER SE COLO. THE GFS DEVELOPS A WEAKER SURFACE LOW FARTHER SOUTH...WHICH WOULD AGAIN FAVOR THE FAR NE PLAINS FOR ANOTHER SHOT AT SEVERE BUT OVERALL COVERAGE OF STORMS TRENDING WAY DOWN SAVE FOR AREAS NEAR THE TX LINE AND POSSIBLY NE CORNER. EVEN DRIER/LESS ACTIVE WITH INCREASED WINDINESS FOR THU WITH AGAIN THE FOCUS FOR STORMS NEAR THE NM/TX LINE ALONG THE DRYLINE. BROAD CYCLONIC FLOW SPREADS EASTWARD OVER THE SOUTHERN ROCKIES AND NEW MEXICO BY FRIDAY WITH DRYLINE REGIME PERSISTING. 500MB HEIGHTS THEN REBOUND INTO THE WEEKEND WITH STRONGER RIDGE PATTERN EARLY NEXT WEEK. SHOULD LOSE INFLUENCE OF THE WESTERLIES BY MON/TUE...AND SIGNS THAT IT MAY PERSIST. KJ && .FIRE WEATHER... SIMILAR WEATHER SCENARIO TO MONDAY EXPECTED TODAY. BEST CHANCES FOR SHOWERS AND THUNDERSTORMS REMAINS EAST OF THE CENTRAL MOUNTAIN CHAIN WITH SLIGHTLY LESS ACTIVITY THAN MONDAY AS A SURFACE LOW BEGINS TO DEVELOP OVER SE COLORADO THIS AFTERNOON AND DRY AIR FROM THE WEST BEGINS TO WORK INTO THE CENTRAL AND NORTHEAST HIGHLANDS. WINDS BECOME MORE SOUTHWESTERLY WEDNESDAY...SCOURING OUT MORE GULF MOISTURE FROM THE SOUTHEAST AND EAST-CENTRAL PLAINS WITH SHOWERS AND STORMS PRIMARILY CONFINED TO THE FAR NE PLAINS. DRY WESTERLIES WIN OUT AREAWIDE BY THURSDAY AS LEE SFC TROUGH STRENGTHENS FURTHER. DRY CONDITIONS CONTINUE THROUGH THE WEEKEND ALONG WITH HIGH HAINES VALUES AND GOOD TO EXCELLENT VENTILATION RATES. WEST WINDS INCREASE FRIDAY AS A WEAK UPPER LEVEL TROUGH MOVES EAST THROUGH THE CENTRAL AND NORTHERN ROCKIES FRIDAY NIGHT INTO SATURDAY. CRITICAL FIRE WEATHER CONDITIONS ARE A POSSIBILITY FRIDAY AFTERNOON AND EARLY EVENING...PRIMARILY FROM THE CENTRAL HIGHLANDS NORTHEASTWARD TO THE NORTHEAST PLAINS. GFS AND ECMWF ARE GOOD AGREEMENT THAT WE FINALLY LOSE THE WESTERLIES ALOFT SUNDAY INTO EARLY NEXT WEEK. FOUR CORNERS HIGH BEGINS TO STRENGTHEN AND DRIFT NORTHWARD OVER SOUTHERN AZ AND SW NM SUNDAY...THEN OVER CENTRAL NM MONDAY. SUNDAY APPEARS TO BE THE HOTTEST DAY DURING THE NEXT 7 DAYS AS THE FOUR CORNERS HIGH MOVES OVERHEAD. MODELS HINTING THAT MONSOON MOISTURE MAY BEGIN TO SEEP NORTHWARD INTO PORTIONS OF SOUTHERN AND PERHAPS CENTRAL NM MONDAY AND TUESDAY. 33 && .AVIATION... 06Z TAF CYCLE GENERAL WLY FLOW ALOFT. LOW LEVEL MOISTURE HAS PUSHED WESTWARD AND INTO THE RGV BUT NOT AS PLENTIFUL AS NEAR THE TEXAS BORDER WHERE AT LEAST ISOLD CONVECTION TO CONTINUE THROUGH POSSIBLY 12Z. LOW LEVEL EASTERLY WINDS TO PERSIST OVER THE PLAINS AND INTO THE RGV THROUGH 12Z WITH SOME POTENTIAL FOR MVFR CIGS TO DEVELOP ALONG THE EAST SLOPES OF THE CENTRAL MT CHAIN...THOUGH NOT INDICATED IN KLVS TAF ATTM. EXPECT ISOLD CONVECTION TO REDEVELOP OVER THE CENTRAL MT CHAIN AND WRN HIGH TERRAIN BY 24/19Z...WITH MAINLY VIRGA WEST OF THE RGV. && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 92 53 93 54 / 0 0 0 0 DULCE........................... 88 41 89 41 / 5 5 0 0 CUBA............................ 89 48 90 48 / 5 5 0 0 GALLUP.......................... 89 45 90 48 / 0 0 0 0 EL MORRO........................ 84 44 84 45 / 0 0 0 0 GRANTS.......................... 90 46 89 46 / 0 0 0 0 QUEMADO......................... 86 50 86 51 / 0 0 0 0 GLENWOOD........................ 93 49 94 50 / 0 0 0 0 CHAMA........................... 82 41 83 42 / 10 5 5 0 LOS ALAMOS...................... 84 58 86 58 / 20 5 0 0 PECOS........................... 80 54 83 54 / 30 10 5 10 CERRO/QUESTA.................... 81 45 82 45 / 20 10 5 5 RED RIVER....................... 73 41 75 42 / 30 20 10 10 ANGEL FIRE...................... 76 39 78 39 / 30 20 10 10 TAOS............................ 84 46 86 46 / 10 10 5 5 MORA............................ 79 49 83 50 / 30 20 20 10 ESPANOLA........................ 90 52 92 53 / 5 5 0 0 SANTA FE........................ 85 56 86 56 / 10 5 0 0 SANTA FE AIRPORT................ 89 54 91 54 / 10 5 0 0 ALBUQUERQUE FOOTHILLS........... 90 63 91 64 / 10 5 0 0 ALBUQUERQUE HEIGHTS............. 93 64 94 65 / 10 5 0 0 ALBUQUERQUE VALLEY.............. 95 61 96 62 / 5 5 0 0 ALBUQUERQUE WEST MESA........... 94 63 95 64 / 10 5 0 0 LOS LUNAS....................... 95 57 96 58 / 5 5 0 0 RIO RANCHO...................... 93 62 95 64 / 10 5 0 0 SOCORRO......................... 98 67 101 66 / 5 5 0 0 SANDIA PARK/CEDAR CREST......... 89 58 90 58 / 20 5 0 0 TIJERAS......................... 90 58 90 59 / 10 5 0 0 MORIARTY/ESTANCIA............... 86 49 88 51 / 20 5 5 5 CLINES CORNERS.................. 84 54 87 56 / 30 10 5 5 GRAN QUIVIRA.................... 88 59 90 59 / 20 5 0 5 CARRIZOZO....................... 90 63 92 64 / 10 5 5 5 RUIDOSO......................... 84 54 86 56 / 30 10 5 10 CAPULIN......................... 79 53 83 54 / 40 30 30 20 RATON........................... 85 53 88 53 / 30 30 20 20 SPRINGER........................ 85 52 89 53 / 30 20 20 10 LAS VEGAS....................... 82 51 86 51 / 30 20 10 10 CLAYTON......................... 86 60 90 61 / 50 40 20 20 ROY............................. 82 57 86 58 / 30 30 20 20 CONCHAS......................... 91 63 95 64 / 30 20 10 10 SANTA ROSA...................... 89 61 93 62 / 20 10 5 10 TUCUMCARI....................... 92 65 97 65 / 30 30 10 20 CLOVIS.......................... 87 63 93 63 / 20 30 10 20 PORTALES........................ 89 64 94 66 / 20 30 10 20 FORT SUMNER..................... 89 64 94 65 / 20 20 10 10 ROSWELL......................... 94 67 99 67 / 20 10 10 10 PICACHO......................... 89 61 93 62 / 30 10 5 10 ELK............................. 84 59 87 61 / 30 10 5 10 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 41
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
150 AM EDT TUE JUN 24 2014 .SYNOPSIS... HIGH PRESSURE WILL GIVE WAY TO INCREASINGLY CLOUDY SKIES AND CHANCES OF SHOWERS AND THUNDERSTORMS BY LATER TONIGHT...AND ESPECIALLY ON TUESDAY INTO WEDNESDAY. HEAVY RAINFALL WILL BE POSSIBLE WITH ANY THUNDERSTORMS...BUT ANTECEDENT DRY WEATHER SHOULD PRECLUDE ANY WIDESPREAD FLOOD THREAT. FAIR AND MAINLY DRY WEATHER RETURNS BY LATER IN THE WEEK INTO NEXT WEEKEND WITH TEMPERATURES AT OR SLIGHTLY ABOVE EARLY SUMMER NORMALS. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 110 AM EDT TUESDAY...I`VE MADE SOME ADJUSTMENTS TO PRECIPITATION PROBABILITIES BASED ON RADAR TRENDS AND REMOVED MENTION OF OVERNIGHT THUNDER WITH THIS UPDATE. WARM AIR ADVECTION REGIME UNDERWAY ACROSS THE NORTH COUNTRY...HOWEVER EXAMINATION OF 00Z BUF ALB AND DTX RAOBS REVEALS AN AIRMASS WITH NO ELEVATED INSTABILITY THAT IS LIKELY ACCOMPANYING THE AREA OF SHOWERS NOW ACROSS THE NORTHERN EDGE OF LAKE ONTARIO. THUS FELT JUSTIFIED IN REMOVING MENTION OF THUNDER THROUGH THE REST OF THE OVERNIGHT. FEEL THAT THE HRRR AND BTV-4 HAVE THE BEST HANDLE ON PRESENT AREA OF SHOWERS...AND BASED ON THESE DATA HAVE ALSO INDICATED SCATTERED TO NUMEROUS SHOWER WORDING IN THE FORECAST FOR THE SAINT LAWRENCE VALLEY AND REST OF NORTHERN NEW YORK GRADUALLY TRANSITIONING EASTWARD TOWARD THE CHAMPLAIN VALLEY TOWARDS MORNING. A WARM AND INCREASINGLY MORE HUMID NIGHT COMPARED TO PRIOR EVENINGS WITH DEWPOINTS ON THE RISE AND LOWS IN THE UPPER 50S TO UPPER 60S IN THE CHAMPLAIN AND SAINT LAWRENCE VALLEY AREAS. && .SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/... AS OF 349 PM EDT MONDAY...INCLEMENT 36-48 HOUR STRETCH OF WEATHER THEN EXPECTED DURING TUE/WED AS WARM FRONT CLEARS NORTHEAST AND A SLOWLY PROGRESSING COLD FRONT SINKS SOUTHEASTWARD INTO THE REGION. MODELS GENERALLY ON BOARD SHOWING THE FRONT SLOWING AS IT PROGRESSES INTO NY/NEW ENGLAND AS A WEAK SURFACE WAVE RIDES ALONG THE BOUNDARY. OF COURSE THE DEVIL IS IN THE DETAILS AS SOLUTIONS HAVE A VARIETY OF IDEAS ON WHERE BEST FORCING SETS UP AND THE DEGREE TO WHICH IT DRIVES THE POTENTIAL OF HEAVIER RAINFALL. COORDINATION WITH WPC SUGGESTS A BLENDED APPROACH THE BEST ROUTE AT THIS POINT...WHICH WILL ACT TO DAMPEN THE MORE ROBUST INDIVIDUAL DETERMINISTIC SOLUTIONS UNTIL WE CAN GET A BETTER GAGE ON HOW THINGS WILL PLAY OUT. WITH DEEP MOISTURE IN PLACE ACROSS THE REGION (PWATS 1-75 TO 2.00 IN) PRIOR IDEA OF LOCALLY HEAVY RAINFALL STILL APPEARS QUITE REASONABLE AT THIS POINT...THOUGH WITH RELATIVELY DRY ANTECEDENT CONDITIONS THE THREAT FOR WIDESPREAD AND/OR RIVER FLOODING APPEARS MINIMAL AT THIS TIME. COULD ALSO SEE A FEW STRONGER STORMS EACH AFTERNOON...BUT PBL INSTABILITY IS GENERALLY MODEST AT BEST AND WITH PREVALENCE OF CLOUD COVER THIS SHOULD INHIBIT HIGHER-END UPDRAFT STRENGTH BY AND LARGE. HIGHS TOMORROW SIMILAR TO TODAY...PERHAPS A TAD COOLER IN THE SLV...THEN GENERALLY 70S FOR WEDNESDAY WITH PREVALENCE OF CLOUDS/PCPN. LOWS REMAINING MILD TUESDAY NIGHT IN THE 60S...LOCALLY NEAR 70 IN THE CHAMPLAIN VALLEY. BY WEDNESDAY NIGHT FRONT CLEARS SLOWLY OFFSHORE WITH ANY LINGERING SHOWERS/STORMS ENDING WEST TO EAST THROUGH TIME. LOW TEMPERATURES SEASONABLE...MID 50S TO LOWER 60S. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 310 PM EDT MONDAY...LARGE SCALE LONG TERM PATTERN WL FEATURE BUILDING MID/UPPER LVL RIDGE ACRS THE SE CONUS BY THE WEEKEND...RESULTING IN A PROGRESSIVE WEST TO SOUTHWEST FLW ALOFT ACRS OUR CWA. IN ADDITION...A WARM AND HUMID AIRMASS IS LIKELY BY THE START OF NEXT WEEK...ALONG WITH THE CHCS FOR ISOLATED TO SCATTERED AFTN/EVENING SHOWERS/STORMS. FOR THURSDAY...HAVE NOTED A SLIGHTLY SLOWER PROGRESSION OF SFC BOUNDARY ACRS OUR EASTERN CWA...ALONG WITH SOME LINGERING MID LVL RH. WL HOLD ONTO A CHC OF SHOWERS ACRS THE CT RIVER VALLEY/PARTS OF CENTRAL VT THRU 15Z...BEFORE DRIER AIR WORKS INTO THE FA. SFC HIGH PRES AND BUILDING RIDGE ALOFT WL KEEP FRIDAY THRU SUNDAY DRY WITH TEMPS NEAR NORMAL. A SPOT SHOWER OR TWO IS POSSIBLE ON FRIDAY/SATURDAY AS EMBEDDED 5H VORT RIDES ACRS THE NORTHERN PERIPHERY OF RIDGE...BUT DEEP LAYER MOISTURE IS LACKING...SO WL KEEP POPS <15% ATTM. PROGGED 85H TEMPS START BTWN 10-12C FOR THURS/FRIDAY...SUPPORTING HIGHS IN THE L70S MTNS TO NEAR 80F WARMER VALLEYS. A RETURN SOUTHERLY FLW WL HELP ADVECT WARMER AIR INTO THE REGION ON SATURDAY/SUNDAY...WITH PROGGED 85H TEMPS WARMING BTWN 14-16C. THIS WL SUPPORT HIGHS IN THE 80S WITH LOWS MAINLY IN THE 60S. BOTH GFS AND 00Z ECMWF SHOW BUILDING RIDGE ACRS THE EASTERN CONUS...AND THE POTENTIAL FOR A WARM/HUMID AIRMASS BUILDING ACRS THE NORTH COUNTRY BY EARLY NEXT WEEK. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... THROUGH 06Z WEDNESDAY...THERE WILL BE A COUPLE OF ROUNDS OF PRECIPITATION DURING THE PERIOD...BUT CONDITIONS WILL GENERALLY REMAIN IN THE VFR CATEGORY. FIRST ROUND OF SCATTERED SHOWERS WILL BE MOVING ACROSS THE AREA THROUGH ABOUT 14Z THIS MORNING...BUT CEILINGS WILL REMAIN ABOVE 5000 FEET AND NO OBSTRUCTION TO VISIBILITIES IS EXPECTED. THERE WILL BE A BREAK IN THE PRECIPITATION BETWEEN 14Z AND 20Z...THEN SHOWERS RETURN ALONG WITH A FEW THUNDERSTORMS FOR THE REMAINDER OF THE PERIOD. AGAIN CEILINGS AND VISIBILITIES WILL BE IN THE VFR CATEGORY...BUT VISIBILITIES COULD LOWER INTO THE MVFR CATEGORY AFTER 00Z. SOUTH TO SOUTHWEST WINDS WILL BE INCREASING EARLY THIS MORNING WITH GUSTS IN THE 15 TO 25 KNOT RANGE EXPECTED THROUGH MUCH OF THE PERIOD. OUTLOOK 06Z WEDNESDAY THROUGH SATURDAY...SLOW MOVING COLD FRONT WILL CONTINUE TO PRODUCE SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ACRS OUR TAF SITES THROUGH 03Z WEDNESDAY. THESE STORMS MAY CONTAIN HEAVY RAIN AND BRIEF GUSTY WINDS TO 40 MPH. BRIEF PERIODS OF MVFR/IFR CONDITIONS WL BE LIKELY IN THE HEAVIER SHOWERS/STORMS ALONG WITH LOCALIZED AREAS OF WIND SHEAR ASSOCIATED WITH THUNDERSTORM OUTFLOW. SOME PATCHY FOG WL BE POSSIBLE OVERNIGHT ON TUES INTO WEDS...ESPECIALLY TAF SITES THAT RECEIVE HEAVY RAINFALL DURING THE EVENING HOURS. ADDITIONAL SHOWERS AND STORMS ARE LIKELY ON WEDS AFTN/EVENING WITH OCCASIONAL MVFR CONDITIONS POSSIBLE...MAINLY ACRS OUR CENTRAL/SOUTHERN TAF SITES. A CLRING TREND DEVELOPS FOR THURSDAY...FRIDAY...AND SATURDAY...WITH MAINLY VFR CONDITIONS...EXCEPT PATCHY FOG/BR POSSIBLE BTWN 08-12Z EACH MORNING AT SLK/MPV. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...JMG NEAR TERM...JMG/RJS/LOCONTO SHORT TERM...JMG LONG TERM...TABER AVIATION...EVENSON/MUCCILLI
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
111 AM EDT TUE JUN 24 2014 .SYNOPSIS... HIGH PRESSURE WILL GIVE WAY TO INCREASINGLY CLOUDY SKIES AND CHANCES OF SHOWERS AND THUNDERSTORMS BY LATER TONIGHT...AND ESPECIALLY ON TUESDAY INTO WEDNESDAY. HEAVY RAINFALL WILL BE POSSIBLE WITH ANY THUNDERSTORMS...BUT ANTECEDENT DRY WEATHER SHOULD PRECLUDE ANY WIDESPREAD FLOOD THREAT. FAIR AND MAINLY DRY WEATHER RETURNS BY LATER IN THE WEEK INTO NEXT WEEKEND WITH TEMPERATURES AT OR SLIGHTLY ABOVE EARLY SUMMER NORMALS. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 110 AM EDT TUESDAY...I`VE MADE SOME ADJUSTMENTS TO PRECIPITATION PROBABILITIES BASED ON RADAR TRENDS AND REMOVED MENTION OF OVERNIGHT THUNDER WITH THIS UPDATE. WARM AIR ADVECTION REGIME UNDERWAY ACROSS THE NORTH COUNTRY...HOWEVER EXAMINATION OF 00Z BUF ALB AND DTX RAOBS REVEALS AN AIRMASS WITH NO ELEVATED INSTABILITY THAT IS LIKELY ACCOMPANYING THE AREA OF SHOWERS NOW ACROSS THE NORTHERN EDGE OF LAKE ONTARIO. THUS FELT JUSTIFIED IN REMOVING MENTION OF THUNDER THROUGH THE REST OF THE OVERNIGHT. FEEL THAT THE HRRR AND BTV-4 HAVE THE BEST HANDLE ON PRESENT AREA OF SHOWERS...AND BASED ON THESE DATA HAVE ALSO INDICATED SCATTERED TO NUMEROUS SHOWER WORDING IN THE FORECAST FOR THE SAINT LAWRENCE VALLEY AND REST OF NORTHERN NEW YORK GRADUALLY TRANSITIONING EASTWARD TOWARD THE CHAMPLAIN VALLEY TOWARDS MORNING. A WARM AND INCREASINGLY MORE HUMID NIGHT COMPARED TO PRIOR EVENINGS WITH DEWPOINTS ON THE RISE AND LOWS IN THE UPPER 50S TO UPPER 60S IN THE CHAMPLAIN AND SAINT LAWRENCE VALLEY AREAS. && .SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/... AS OF 349 PM EDT MONDAY...INCLEMENT 36-48 HOUR STRETCH OF WEATHER THEN EXPECTED DURING TUE/WED AS WARM FRONT CLEARS NORTHEAST AND A SLOWLY PROGRESSING COLD FRONT SINKS SOUTHEASTWARD INTO THE REGION. MODELS GENERALLY ON BOARD SHOWING THE FRONT SLOWING AS IT PROGRESSES INTO NY/NEW ENGLAND AS A WEAK SURFACE WAVE RIDES ALONG THE BOUNDARY. OF COURSE THE DEVIL IS IN THE DETAILS AS SOLUTIONS HAVE A VARIETY OF IDEAS ON WHERE BEST FORCING SETS UP AND THE DEGREE TO WHICH IT DRIVES THE POTENTIAL OF HEAVIER RAINFALL. COORDINATION WITH WPC SUGGESTS A BLENDED APPROACH THE BEST ROUTE AT THIS POINT...WHICH WILL ACT TO DAMPEN THE MORE ROBUST INDIVIDUAL DETERMINISTIC SOLUTIONS UNTIL WE CAN GET A BETTER GAGE ON HOW THINGS WILL PLAY OUT. WITH DEEP MOISTURE IN PLACE ACROSS THE REGION (PWATS 1-75 TO 2.00 IN) PRIOR IDEA OF LOCALLY HEAVY RAINFALL STILL APPEARS QUITE REASONABLE AT THIS POINT...THOUGH WITH RELATIVELY DRY ANTECEDENT CONDITIONS THE THREAT FOR WIDESPREAD AND/OR RIVER FLOODING APPEARS MINIMAL AT THIS TIME. COULD ALSO SEE A FEW STRONGER STORMS EACH AFTERNOON...BUT PBL INSTABILITY IS GENERALLY MODEST AT BEST AND WITH PREVALENCE OF CLOUD COVER THIS SHOULD INHIBIT HIGHER-END UPDRAFT STRENGTH BY AND LARGE. HIGHS TOMORROW SIMILAR TO TODAY...PERHAPS A TAD COOLER IN THE SLV...THEN GENERALLY 70S FOR WEDNESDAY WITH PREVALENCE OF CLOUDS/PCPN. LOWS REMAINING MILD TUESDAY NIGHT IN THE 60S...LOCALLY NEAR 70 IN THE CHAMPLAIN VALLEY. BY WEDNESDAY NIGHT FRONT CLEARS SLOWLY OFFSHORE WITH ANY LINGERING SHOWERS/STORMS ENDING WEST TO EAST THROUGH TIME. LOW TEMPERATURES SEASONABLE...MID 50S TO LOWER 60S. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 310 PM EDT MONDAY...LARGE SCALE LONG TERM PATTERN WL FEATURE BUILDING MID/UPPER LVL RIDGE ACRS THE SE CONUS BY THE WEEKEND...RESULTING IN A PROGRESSIVE WEST TO SOUTHWEST FLW ALOFT ACRS OUR CWA. IN ADDITION...A WARM AND HUMID AIRMASS IS LIKELY BY THE START OF NEXT WEEK...ALONG WITH THE CHCS FOR ISOLATED TO SCATTERED AFTN/EVENING SHOWERS/STORMS. FOR THURSDAY...HAVE NOTED A SLIGHTLY SLOWER PROGRESSION OF SFC BOUNDARY ACRS OUR EASTERN CWA...ALONG WITH SOME LINGERING MID LVL RH. WL HOLD ONTO A CHC OF SHOWERS ACRS THE CT RIVER VALLEY/PARTS OF CENTRAL VT THRU 15Z...BEFORE DRIER AIR WORKS INTO THE FA. SFC HIGH PRES AND BUILDING RIDGE ALOFT WL KEEP FRIDAY THRU SUNDAY DRY WITH TEMPS NEAR NORMAL. A SPOT SHOWER OR TWO IS POSSIBLE ON FRIDAY/SATURDAY AS EMBEDDED 5H VORT RIDES ACRS THE NORTHERN PERIPHERY OF RIDGE...BUT DEEP LAYER MOISTURE IS LACKING...SO WL KEEP POPS <15% ATTM. PROGGED 85H TEMPS START BTWN 10-12C FOR THURS/FRIDAY...SUPPORTING HIGHS IN THE L70S MTNS TO NEAR 80F WARMER VALLEYS. A RETURN SOUTHERLY FLW WL HELP ADVECT WARMER AIR INTO THE REGION ON SATURDAY/SUNDAY...WITH PROGGED 85H TEMPS WARMING BTWN 14-16C. THIS WL SUPPORT HIGHS IN THE 80S WITH LOWS MAINLY IN THE 60S. BOTH GFS AND 00Z ECMWF SHOW BUILDING RIDGE ACRS THE EASTERN CONUS...AND THE POTENTIAL FOR A WARM/HUMID AIRMASS BUILDING ACRS THE NORTH COUNTRY BY EARLY NEXT WEEK. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... THROUGH 00Z WEDNESDAY...PRIMARILY VFR EXPECTED THROUGH THE PERIOD. CLOUDS WILL BE ON THE INCREASE OVERNIGHT AS WARM FRONT APPROACHES AND SUBSEQUENTLY PASSES THROUGH REGION. HOWEVER CEILINGS WILL REMAIN VFR. WILL LIKELY SEE SOME SCATTERED RAIN SHOWERS FROM ONGOING CONVECTION ACROSS THE EASTERN GREAT LAKES...BUT ACTIVITY WILL DECAY OVER TIME. BEST CHANCE FOR SHOWERS FROM 06Z-15Z ACROSS NORTHERN NEW YORK TAF SITES AND 10Z-15Z IN NORTHERN/CENTRAL VERMONT. RUT WILL LIKELY SEE NO IMPACT AT ALL. EVEN IN RAIN SHOWERS...CONDITIONS LIKELY TO REMAIN MAINLY VFR. WARM FRONT WILL LIFT NORTH AND EAST OF AREA ON TUESDAY BEFORE COLD FRONT APPROACHES FROM THE NORTH AND WEST LATER TUESDAY WITH ADDITIONAL CHANCES FOR SHOWERS AND SCATTERED THUNDERSTORMS LATE TUESDAY AFTERNOON AND ESPECIALLY EVENING. ANY THUNDERSTORM MAY PRODUCE HEAVY RAIN (AND POTENTIAL BRIEF MVFR/IFR CONDITIONS) AND GUSTY WINDS. SOUTH WINDS WILL BE INCREASING THROUGH TIME...ESPECIALLY AT BTV WHERE GUSTS TO 20 KNOTS ARE FORECAST TONIGHT AND UP TO 27 KNOTS LATER TUESDAY. ELSEWHERE GUSTS WILL TOP OUT 18-23 KNOTS THROUGH 00Z WEDNESDAY...EXCEPT LOCALLY HIGHER IN ANY THUNDERSTORMS. OUTLOOK 00Z WEDNESDAY THROUGH SATURDAY...SLOW MOVING COLD FRONT WILL CONTINUE TO PRODUCE SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ACRS OUR TAF SITES THROUGH 03Z WEDNESDAY. THESE STORMS MAY CONTAIN HEAVY RAIN AND BRIEF GUSTY WINDS TO 40 MPH. BRIEF PERIODS OF MVFR/IFR CONDITIONS WL BE LIKELY IN THE HEAVIER SHOWERS/STORMS ALONG WITH LOCALIZED AREAS OF WIND SHEAR ASSOCIATED WITH THUNDERSTORM OUTFLOW. SOME PATCHY FOG WL BE POSSIBLE OVERNIGHT ON TUES INTO WEDS...ESPECIALLY TAF SITES THAT RECEIVE HEAVY RAINFALL DURING THE EVENING HOURS. ADDITIONAL SHOWERS AND STORMS ARE LIKELY ON WEDS AFTN/EVENING WITH OCCASIONAL MVFR CONDITIONS POSSIBLE...MAINLY ACRS OUR CENTRAL/SOUTHERN TAF SITES. A CLRING TREND DEVELOPS FOR THURSDAY...FRIDAY...AND SATURDAY...WITH MAINLY VFR CONDITIONS...EXCEPT PATCHY FOG/BR POSSIBLE BTWN 08-12Z EACH MORNING AT SLK/MPV. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...JMG NEAR TERM...JMG/RJS/LOCONTO SHORT TERM...JMG LONG TERM...TABER AVIATION...MUCCILLI
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
337 AM EDT TUE JUN 24 2014 .SYNOPSIS... BERMUDA HIGH PRESSURE WILL OVERSPREAD THE CAROLINAS IN THE DAYS AHEAD...ACCOMPANIED BY DEVELOPMENT OF A PIEDMONT TROUGH. THIS WILL LEAD TO TEMPERATURES RISING SEVERAL DEGREES ABOVE NORMAL FOR THE REMAINDER OF THE WEEK ALONG WITH SCATTERED THUNDERSTORMS. && .NEAR TERM /THROUGH TONIGHT/... AS OF 330 AM TUESDAY...THE REMNANTS OF A FRONTAL BOUNDARY SOUTH OF THE AREA IS NOW LIFTING NORTHWARD ACROSS SOUTH CAROLINA EARLY THIS MORNING...AND IS DISCERNIBLE WITH SHOWERS IGNITING ALONG IT WITHIN A CORRIDOR OF ENHANCED LOW-LEVEL CONVERGENCE. THIS FEATURE WILL INFLUENCE NEAR TERM WEATHER BRINGING INCREASING POPS FROM SOUTH TO NORTH THROUGH THE COURSE OF THE DAY. THE BOUNDARY WILL INTERACT WITH SEA BREEZE CONVERGENCE WHICH MAY SHIFT CONVECTION FARTHER WEST IN THE MIDDLE AND LATE AFTERNOON. DEEPER MOISTURE IS POOLED ACROSS SC AND THIS IS WHERE THE HIGHER POPS WILL RESIDE FOR A GOOD PORTION OF THE DAY. OF CONCERN IS THE POTENTIAL FOR LOCALIZED FLOODING AS PRECIPITABLE WATERS RISE TO AROUND 2 INCHES WITH SOMEWHAT OF A SLUGGISH STORM MOTION. THIS COULD LEAD TO SEVERAL INCHES OF RAIN IN A SHORT TIME OVER CONFINED LOCATIONS. STORMS SHOULD MOVE GENERALLY SOUTH TO NORTH AROUND 10 MPH THIS AFTERNOON. MAXIMUM TEMPERATURE WILL RISE TO NEAR NORMAL LEVELS FOR LATE JUNE. AS RETURN FLOW GEARS UP...MINIMUMS INTO DAYBREAK WEDNESDAY WILL REMAIN BALMY AND SLIGHTLY ABOVE NORMAL FOR DAYBREAK JUNE 25TH. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 AM TUESDAY...BERMUDA HIGH AND WEAK MID LEVEL TROUGHING WILL KEEP THE PERIOD ACTIVE WITH THE SEA BREEZE AND PIEDMONT TROUGH BEING PROMINENT FEATURES. THE REMAINS OF A WEAK COLD FRONT MOVES INTO THE AREA LATER WED INTO THU BUT THIS FEATURE WILL BE VERY WEAK BY THE TIME IT REACHES THE AREA...LACKING ANY MID LEVEL PUSH. THE BOUNDARY MAY SERVE AS A FOCUS FOR CONVECTION...ESPECIALLY WED NIGHT AND AS A RESULT WILL CARRY MENTIONABLE POP WED INTO THU. AHEAD OF THIS FEATURE DEEP MOISTURE...PRECIPITABLE WATER VALUES WED LINGER OVER 2 INCHES ACROSS MUCH OF THE AREA...AND DIURNAL INSTABILITY WILL LEAD TO AFTERNOON CONVECTION. PROFILES DO NOT SUGGEST A SIGNIFICANT SEVERE THREAT...BUT CANNOT RULE OUT AN ISOLATED STRONG/SEVERE STORM. STORM MOTIONS AROUND 10 KT WILL INCREASE THE FLOODING POTENTIAL. PATTERN ALOFT BECOMES A LITTLE MORE PROGRESSIVE ON THU WITH MID LEVEL FLOW TURNING WESTERLY. THIS WILL CAUSE A DROP IN PRECIPITABLE WATER VALUES...THOUGH MOST OF THE AREA WILL REMAIN ABOVE CLIMO FOR LATE JUNE. MID LEVEL DRY AIR WILL AFFECT STORM COVERAGE BUT STILL THINK CHC POP IS WARRANTED. AS IS THE CASE ON WED THE SEA BREEZE AND PIEDMONT TROUGH WILL BE ACTIVE BUT STORM MOTIONS COULD BE WELL UNDER 10 MPH. ALTHOUGH DEEPER MOISTURE IS LESS THE SLOW STORM MOTIONS WILL AGAIN POSE A FLOODING THREAT. HIGHS WILL RUN ABOVE CLIMO...LOW TO MID 90S AWAY FROM THE COAST WITH LOWS IN THE LOW TO MID 70S. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 3 AM TUESDAY...PROGRESSIVE FLOW ALOFT ON FRI WILL TRANSITION TO GRADUAL RIDGING OVER THE SOUTHEAST FOR THE WEEKEND AND START OF NEXT WEEK. WEAK NATURE OF THE RIDGE LATE IN THE PERIOD LIMITS AMOUNT OF SUBSIDENCE/DRYING...IN FACT FORECAST SOUNDINGS SHOW PRECIPITABLE WATER VALUES INCREASING LATE IN THE PERIOD. VALUES WILL RANGE FROM 1.7 TO 2 INCHES FRI THROUGH MON...ABOVE CLIMO FOR THIS TIME OF YEAR. AT THE SURFACE BERMUDA HIGH WILL CONTINUE TO PUMP WARM MOIST AIR INTO THE SOUTHEAST AND UNDER THE BUILDING MID LEVEL RIDGE KEEP HIGHS IN THE 90S WITH LOWS IN THE LOW 70S. DEEP MOISTURE AND LIMITED CAPPING WILL KEEP SEA BREEZE AND PIEDMONT TROUGH ACTIVE EACH DAY. PRESENCE OF MID LEVEL RIDGE LATER IN THE PERIOD WILL LEAD TO SOME REDUCTION IN COVERAGE AND POP WILL SHOW A GENERAL DECREASING TREND THROUGH THE PERIOD. && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... AS OF 06Z...WITH RAIN DURING THE LATE EVENING VISIBILITIES WILL START TO COME DOWN AT LBT TO MVFR WITH THE OTHER TERMINALS AT VFR FOR NOW. HAVE MENTION OF MVFR AT OTHER TERMINALS AS LOW CLOUDS AND SHOWERS OFF THE COAST WORK THEIR WAY TO THE COAST. HIGH RESOLUTION WRF AND HRRR SHOW PRECIPITATION WORKING ONTO THE COAST OF SC AND MOVING INTO THE MYRTLES BEFORE SUNRISE AND INTO ILM AFTER SUNRISE. MODELS HAD A GOOD HANDLE ON LAST NIGHTS PRECIPITATION SO WILL PAY ATTENTION AND INTRODUCE THE PRECIPITATION. THIS IS A BIG CHANGE FROM THE 00Z TAFS AND HAVE ALSO MENTION CONVECTION ACROSS THE INLAND TERMINALS DURING THE AFTERNOON AS WELL. POPS HAVE INCREASED FROM THESE MODELS AND MOIST FLOW OFF THE OCEAN WITH A WEAK FRONTAL BOUNDRY TO OUR SOUTH AND A WEAK VORT MAX MOVING ACROSS THE REGION SHOULD ALL INTERACT TO INCREASE THE CHANCE OF PRECIPITATION ACROSS THE REGION THROUGHOUT THE EARLY MORNING HOURS AND INTO THE AFTERNOON. TERMINALS WILL BOUNCE BETWEEN VFR AND MVFR THROUGHOUT THE DAY WITH NO REAL GOOD FEEL ON WHEN THIS WILL OCCUR. WINDS WILL VEER FROM THE E TO THE SE ALONG THE COASTAL TERMINALS DURING THE MORNING WITH THE SEA BREEZE FRONT REACHING THE INLAND TERMINALS DURING THE AFTERNOON AND ENHANCING LIFT AND MOISTURE. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 330 AM TUESDAY...SHOWERS WILL DOT THE WATERS AS WINDS VEER TO SE AND S-SW TONIGHT. A WEAK WARM FRONT LIFTING NORTH COULD TRIP OFF A FEW TSTMS OVER THE WATERS TODAY THROUGH TONIGHT. REMEMBER THAT WINDS AS WELL AS WAVES ARE LOCALLY HIGHER IN AND NEAR TSTMS. NO ADVISORIES EXPECTED. SEAS MAINLY 2-3 FEET IN A MIX OF E-ESE WAVES 2 FT EVERY 5-6 SECONDS...AND ESE WAVES 1.5 FEET EVERY 9-10 SECONDS. THE AFTERNOON SEA BREEZE WILL PRODUCE ISOLATED GUSTS TO 20 KT INSHORE BETWEEN 3PM-6PM. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 AM TUESDAY...GRADIENT TIGHTENS WED AS PIEDMONT TROUGH STRENGTHENS AND BERMUDA HIGH CONTINUES TO BUILD IN FROM THE WEST. SPEEDS WILL BE A SOLID 15 KT WITH POTENTIAL FOR 20 KT LATER IN THE AFTERNOON. WEAK BOUNDARY MOVES TO THE COAST WED NIGHT INTO THU AND DISSIPATES. THIS WILL WEAKEN THE GRADIENT AND SPEEDS WILL DROP CLOSER TO 10 KT ON THU. SEA BREEZE WILL AGAIN DEVELOP WITH SOLID 15 KT POSSIBLE NEAR SHORE. SEAS BUILD TO 2 TO 4 FT WED INTO WED NIGHT WILL DROP BACK TO 2 TO 3 FT ON THU. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 3 AM TUESDAY...BERMUDA HIGH WILL REMAIN IN CONTROL THROUGH THE PERIOD WITH SOUTHWEST FLOW 10 TO 15 KT EACH DAY. SEAS 2 TO 3 FT WILL CONTINUE TO BE DOMINATED BY SHORT PERIOD SOUTHWEST WIND WAVE. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...MJC SHORT TERM...III LONG TERM...III AVIATION...MAC/MJC
AREA FORECAST DISCUSSION
NWS RALEIGH NC
240 AM EDT TUE JUN 24 2014 .SYNOPSIS...HIGH PRESSURE EXTENDING INTO OUR REGION FROM OFFSHORE THE NEW ENGLAND COAST WILL MOVE AWAY TODAY...AND YIELD TO A SURFACE PRESSURE TROUGH THAT WILL DEVELOP OVER THE WESTERN CAROLINAS THIS AFTERNOON. THE TROUGH WILL STRENGTHEN AND SHIFT EAST INTO THE CENTRAL AND EASTERN CAROLINAS FOR WEDNESDAY AND THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1020 PM MONDAY... CONVECTION IS STILL DEVELOPING ALONG THE NORTH-NORTHWESTWARD ADVANCING SEABREEZE THIS EVENING... OVER OUR FAR SOUTHERN SANDHILLS. HOWEVER... IT IS BEGINNING TO WANE IN COVERAGE ACROSS OUR FAR SOUTH/SOUTHWESTERN REACHES THIS EVENING.... WHICH MATCHES UP WELL WITH THE WEAKENING INSTABILITY ACROSS CENTRAL NC. THE BEST LINGERING INSTABILITY REMAINS TO OUR WEST AND SOUTH.... WHERE CONVECTION IS EXPECTED TO LINGER THE LONGEST... LATE EVENING/VERY EARLY TUESDAY MORNING. HOWEVER... LOW LEVEL MOISTURE IS EXPECTED TO INCREASE ACROSS THE AREA THIS EVENING AND OVERNIGHT AS HIGH PRESSURE BEGINS TO RETREAT OFF TO THE NORTHEAST. THIS WILL YIELD A DEVELOPING LOW LEVEL SOUTHERLY TO SOUTHEASTERLY FLOW... WITH THE POTENTIAL FOR STRATUS DEVELOPING ACROSS WESTERN PORTIONS OF CENTRAL NC FIRST THEN SPREADING EASTWARD. LOCATIONS ACROSS THE FAR NORTHEAST (NORTHERN COASTAL PLAIN AND FAR NORTHEAST PIEDMONT) MAY SEE MOSTLY CLEAR SKIES OVERNIGHT THOUGH. MEANWHILE... THE MID LEVEL S/W RIDGE AXIS WILL SLOWLY BEGIN TO SHIFT EASTWARD TONIGHT... POSSIBLY ALLOWING A WEAK DISTURBANCE TO LIFT NORTH-NORTHEASTWARD AND INTO/ACROSS THE WESTERN PIEDMONT. THE LATEST RAP AND HRRR IS SHOWING THIS FEATURE... COUPLED WITH INCREASING LOW LEVEL SOUTHERLY/SOUTHEASTERLY FLOW... HELPING TO DEVELOP SOME CONVECTION OVERNIGHT ACROSS OUR FAR WESTERN PIEDMONT. GIVEN THE TIME OF NIGHT WITH THE RAP SHOWING FURTHER STABILIZATION ACROSS OUR AREA AND TO THE WEST... CONFIDENCE REMAINS LOW OF SEEING MUCH IN THE WAY OF ANY SHOWERS AFTER MIDNIGHT (WHEN THE RAP AND HRRR SHOW SHOWERS DEVELOPING). THUS... WILL JUST ADDED A SLIGHT CHANCE OF SHOWERS TO OUR WESTERN PIEDMONT AT THIS TIME IN THE 04-11Z TIME FRAME. LOWS TUESDAY MORNING ARE EXPECTED TO RANGE NEAR THE MID 60S NORTHEAST TO NEAR 70 FAR SOUTHWEST/SOUTH. && .SHORT TERM /TUESDAY AND TUESDAY NIGHT/... AS OF 300 PM MONDAY... A LOW AMPLITUDE SHORTWAVE TROUGH AND IT`S WEAK SURFACE FRONT REFLECTION WILL PROGRESS EAST-NORTHEASTWARD FROM THE MS VALLEY AND INTO THE OHIO VALLEY TUESDAY NIGHT. WHILE THIS FEATURE WILL REMAIN WEST AND NORTH OF THE AREA...WEAK SHORTWAVE IMPULSES EJECTING EAST- NORTHEASTWARD OUT AHEAD OF THE TROUGH COULD POSSIBLY PROVIDE SOME WEAK SUPPORT ALOFT IN CONCERT WITH INCREASINGLY BOUNDARY LAYER MOISTURE/BUOYANCY AS SOUTHERLY RETURN OVERSPREADS THE AREA WITH THE DEVELOPMENT OF A LEE TROUGH TUESDAY EVENING/NIGHT. HIGHEST POPS SHOULD EXTEND ACROSS THE SOUTHERN AND WESTERN ZONES...LOWEST IN THE NORTHEAST. GIVEN WEAK FORCING AND SHEAR AND ONLY MODEST DESTABILIZATION OF 1000-1500 J/KG...SEVERE THREAT WILL BE TOO LOW/ISOLATED TO WARRANT A MENTION IN THE HWO. HIGHS IN THE MID 80S NORTH TO LOWER 90S SOUTH. LOWS 68 TO 72. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 240 AM TUESDAY... GUIDANCE SUGGESTS THAT PRECIP CHANCES ACROSS CENTRAL NC WILL TREND DOWNWARD ON THURSDAY...AND REMAIN BELOW CLIMO ON FRIDAY...AS THE SFC BOUNDARY STALLS TO OUR EAST ON THURSDAY AND DRIER AIR MOVES IN FROM THE WEST IN THE WAKE OF THE MID-LEVEL TROUGH AXIS PASSING BY TO OUR EAST AND NORTHEAST (24 HOUR CLIMO POP FOR CENTRAL NC IS AROUND 30 PERCENT). RIGHT NOW...LOOKS LIKE THE BETTER CHANCE FOR A DRY DAY WILL BE THURSDAY...BECAUSE BY LATE FRIDAY...THE SFC TROUGH WILL BECOME REFOCUSED ACROSS THE PIEDMONT AND PWAT WILL BE BACK ON THE INCREASE. OVER THE WEEKEND...THE CHANCE FOR RAIN WILL INCREASE TO OR ABOVE CLIMO...AS A BACKDOOR FRONT APPROACHES FROM THE NORTH. THE RISK FOR SCATTERED SHOWERS AND TSTMS WILL CONTINUE ON MONDAY AS THE AFOREMENTIONED BOUNDARY REMAINS INVOF OUR CWA...AND AMPLE MOISTURE WILL REMAIN POOLED ACROSS THE AREA. ITS WORTH NOTING THAT DURING THE ENTIRE LONG TERM PERIOD...BULK SHEAR ISN`T THAT IMPRESSIVE...SO WHILE DAYTIME INSTABILITY MAY BE PLENTIFUL AND WE CAN NEVER RULE OUT THE POTENTIAL FOR AN ISOLATED STRONG-TO-SEVERE TSTM THIS TIME OF YEAR...BULK SHEAR PARAMETERS ACROSS CENTRAL NC ARE NOT FAVORABLE FOR ORGANIZED OR WIDESPREAD SEVERE CONVECTION DURING THIS TIME. AS FOR TEMPS...LATEST MEX SHOWS TEMPS CLIMBING ABOVE NORMAL THURSDAY THROUGH SATURDAY WITH HIGHS IN THE MID 90S AND LOWS NEAR 70. HOWEVER...FORECAST LOW LEVEL THICKNESSES ARE FAIRLY CLOSE TO NORMAL (1410-1420M)...SO WILL LEAN TOWARD THE COOLER SIDE OF THE GUIDANCE ENVELOPE FOR THIS TIME. TEMPS SHOULD TREND COOLER LATE IN THE WEEKEND INTO EARLY NEXT WEEK WITH INCREASED CLOUD COVERAGE AND RAIN CHANCES. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 220 AM TUESDAY... SSE FLOW JUST ABOVE THE SURFACE...IN RETURN FLOW AROUND OFFSHORE HIGH PRESSURE...WILL RESULT IN PERIODS OF SCT TO BKN MVFR RANGE CLOUD COVER THIS MORNING...MAINLY AT KINT/KGSO/KFAY/KRDU...WHILE A BRIEF PERIOD OF VISIBILITY RESTRICTIONS WILL BE POSSIBLE AT KRWI DUE TO LOCAL/RIVER BASIN/DRAINAGE EFFECTS. OTHERWISE...VFR CONDITIONS ARE EXPECTED FOR THE MAJORITY OF THE TAF PERIOD. SCATTERED SHOWERS AND STORMS WILL AFFECT MAINLY AREAS NEAR THE SC BORDER...INCLUDING IN THE VICINITY OF KFAY...THIS AFTERNOON. OUTLOOK: STRATUS PROBABLE LATE TONIGHT-EARLY WED. A CHANCE OF AFTERNOON SHOWERS AND STORMS AREA-WIDE ON WED AND FRI...WITH LESSER CHANCES...MAINLY AT EASTERN TERMINALS...ON THU. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...MWS NEAR TERM...BSD SHORT TERM...CBL LONG TERM...NP AVIATION...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
223 AM EDT TUE JUN 24 2014 .SYNOPSIS...HIGH PRESSURE EXTENDING INTO OUR REGION FROM OFFSHORE THE NEW ENGLAND COAST WILL MOVE AWAY TODAY...AND YIELD TO A SURFACE PRESSURE TROUGH THAT WILL DEVELOP OVER THE WESTERN CAROLINAS THIS AFTERNOON. THE TROUGH WILL STRENGTHEN AND SHIFT EAST INTO THE CENTRAL AND EASTERN CAROLINAS FOR WEDNESDAY AND THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1020 PM MONDAY... CONVECTION IS STILL DEVELOPING ALONG THE NORTH-NORTHWESTWARD ADVANCING SEABREEZE THIS EVENING... OVER OUR FAR SOUTHERN SANDHILLS. HOWEVER... IT IS BEGINNING TO WANE IN COVERAGE ACROSS OUR FAR SOUTH/SOUTHWESTERN REACHES THIS EVENING.... WHICH MATCHES UP WELL WITH THE WEAKENING INSTABILITY ACROSS CENTRAL NC. THE BEST LINGERING INSTABILITY REMAINS TO OUR WEST AND SOUTH.... WHERE CONVECTION IS EXPECTED TO LINGER THE LONGEST... LATE EVENING/VERY EARLY TUESDAY MORNING. HOWEVER... LOW LEVEL MOISTURE IS EXPECTED TO INCREASE ACROSS THE AREA THIS EVENING AND OVERNIGHT AS HIGH PRESSURE BEGINS TO RETREAT OFF TO THE NORTHEAST. THIS WILL YIELD A DEVELOPING LOW LEVEL SOUTHERLY TO SOUTHEASTERLY FLOW... WITH THE POTENTIAL FOR STRATUS DEVELOPING ACROSS WESTERN PORTIONS OF CENTRAL NC FIRST THEN SPREADING EASTWARD. LOCATIONS ACROSS THE FAR NORTHEAST (NORTHERN COASTAL PLAIN AND FAR NORTHEAST PIEDMONT) MAY SEE MOSTLY CLEAR SKIES OVERNIGHT THOUGH. MEANWHILE... THE MID LEVEL S/W RIDGE AXIS WILL SLOWLY BEGIN TO SHIFT EASTWARD TONIGHT... POSSIBLY ALLOWING A WEAK DISTURBANCE TO LIFT NORTH-NORTHEASTWARD AND INTO/ACROSS THE WESTERN PIEDMONT. THE LATEST RAP AND HRRR IS SHOWING THIS FEATURE... COUPLED WITH INCREASING LOW LEVEL SOUTHERLY/SOUTHEASTERLY FLOW... HELPING TO DEVELOP SOME CONVECTION OVERNIGHT ACROSS OUR FAR WESTERN PIEDMONT. GIVEN THE TIME OF NIGHT WITH THE RAP SHOWING FURTHER STABILIZATION ACROSS OUR AREA AND TO THE WEST... CONFIDENCE REMAINS LOW OF SEEING MUCH IN THE WAY OF ANY SHOWERS AFTER MIDNIGHT (WHEN THE RAP AND HRRR SHOW SHOWERS DEVELOPING). THUS... WILL JUST ADDED A SLIGHT CHANCE OF SHOWERS TO OUR WESTERN PIEDMONT AT THIS TIME IN THE 04-11Z TIME FRAME. LOWS TUESDAY MORNING ARE EXPECTED TO RANGE NEAR THE MID 60S NORTHEAST TO NEAR 70 FAR SOUTHWEST/SOUTH. && .SHORT TERM /TUESDAY AND TUESDAY NIGHT/... AS OF 300 PM MONDAY... A LOW AMPLITUDE SHORTWAVE TROUGH AND IT`S WEAK SURFACE FRONT REFLECTION WILL PROGRESS EAST-NORTHEASTWARD FROM THE MS VALLEY AND INTO THE OHIO VALLEY TUESDAY NIGHT. WHILE THIS FEATURE WILL REMAIN WEST AND NORTH OF THE AREA...WEAK SHORTWAVE IMPULSES EJECTING EAST- NORTHEASTWARD OUT AHEAD OF THE TROUGH COULD POSSIBLY PROVIDE SOME WEAK SUPPORT ALOFT IN CONCERT WITH INCREASINGLY BOUNDARY LAYER MOISTURE/BUOYANCY AS SOUTHERLY RETURN OVERSPREADS THE AREA WITH THE DEVELOPMENT OF A LEE TROUGH TUESDAY EVENING/NIGHT. HIGHEST POPS SHOULD EXTEND ACROSS THE SOUTHERN AND WESTERN ZONES...LOWEST IN THE NORTHEAST. GIVEN WEAK FORCING AND SHEAR AND ONLY MODEST DESTABILIZATION OF 1000-1500 J/KG...SEVERE THREAT WILL BE TOO LOW/ISOLATED TO WARRANT A MENTION IN THE HWO. HIGHS IN THE MID 80S NORTH TO LOWER 90S SOUTH. LOWS 68 TO 72. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... AS OF 300 PM MONDAY... THE BEST TIME FRAME FOR PRECIP IN THE LONG TERM PERIOD LOOKS TO BE WEDNESDAY/WEDNESDAY NIGHT AS A SHORTWAVE TROUGH PROGRESSES EAST OVER THE REGION...PUSHING A SURFACE FRONT TOWARDS THE AREA. THE BEST FORCING WILL REMAIN NORTH OF THE AREA...BUT GIVEN THE BETTER (ALBEIT WEAK) SUPPORT ALOFT AND CONVERGENCE AT THE SURFACE...SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED DURING THE DAY...LIKELY PERSISTING INTO THE OVERNIGHT HOURS. GIVEN WEAK DEEP LAYER SHEAR...AS WELL AS WEAK MID LEVEL LAPSE RATES...SEVERE POTENTIAL WILL BE RATHER LIMITED DESPITE THE MODERATE TO STRONG INSTABILITY THAT IS EXPECTED TO BE OVER THE AREA. FOR THE REMAINDER OF THE LONG TERM PERIOD...THERE IS QUITE A BIT OF SPREAD AMONG THE MODELS... LEADING TO DECREASED CONFIDENCE. OVERALL...RIDGING ALOFT (ALTHOUGH RATHER FLAT) IS PROGGED TO BUILD BACK OVER THE AREA DURING THE LATTER HALF OF THE WEEK...ALLOWING SOME MID LEVEL DRYING TO OCCUR. NEVERTHELESS...MODERATE TO STRONG INSTABILITY WILL RESULT IN CONTINUED PRECIP CHANCES...ALTHOUGH COVERAGE MAY BE SLIGHTLY LESS. DETAILS IN THE MID/UPPER PATTERN BECOMES EVEN MORE UNCLEAR FOR THE WEEKEND AND EARLY NEXT WEEK...BUT NEVERTHELESS PRECIP CHANCES WILL LIKELY PERSIST THROUGH EARLY NEXT WEEK GIVEN THE TYPICAL SUMMERTIME AIRMASS. HIGH TEMPS WILL GENERALLY IN THE UPPER 80S TO LOWER 90S TO START THE PERIOD WITH LOW TO MID 90S EXPECTED BY THE END OF THE WEEK. OVERNIGHT LOWS WILL MOSTLY BE IN THE UPPER 60S TO LOWER 70S. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 220 AM TUESDAY... SSE FLOW JUST ABOVE THE SURFACE...IN RETURN FLOW AROUND OFFSHORE HIGH PRESSURE...WILL RESULT IN PERIODS OF SCT TO BKN MVFR RANGE CLOUD COVER THIS MORNING...MAINLY AT KINT/KGSO/KFAY/KRDU...WHILE A BRIEF PERIOD OF VISIBILITY RESTRICTIONS WILL BE POSSIBLE AT KRWI DUE TO LOCAL/RIVER BASIN/DRAINAGE EFFECTS. OTHERWISE...VFR CONDITIONS ARE EXPECTED FOR THE MAJORITY OF THE TAF PERIOD. SCATTERED SHOWERS AND STORMS WILL AFFECT MAINLY AREAS NEAR THE SC BORDER...INCLUDING IN THE VICINITY OF KFAY...THIS AFTERNOON. OUTLOOK: STRATUS PROBABLE LATE TONIGHT-EARLY WED. A CHANCE OF AFTERNOON SHOWERS AND STORMS AREA-WIDE ON WED AND FRI...WITH LESSER CHANCES...MAINLY AT EASTERN TERMINALS...ON THU. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...MWS NEAR TERM...BSD SHORT TERM...CBL LONG TERM...KRD AVIATION...MWS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
147 AM EDT TUE JUN 24 2014 .SYNOPSIS... BERMUDA HIGH PRESSURE WILL OVERSPREAD THE CAROLINAS IN THE DAYS AHEAD...ACCOMPANIED BY DEVELOPMENT OF A PIEDMONT TROUGH. THIS WILL LEAD TO TEMPERATURES RISING SEVERAL DEGREES ABOVE NORMAL FOR THE REMAINDER OF THE WEEK ALONG WITH SCATTERED THUNDERSTORMS. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1 AM TUESDAY...ALTHOUGH THERE IS NOT MUCH IMPETUS TO KEEP THE CONVECTION GOING THROUGH THE NIGHT...THE SAME WAS TRUE FOR THE LAST COUPLE OF NIGHTS...AND YET SOME CONVECTION MANAGED TO PERSIST. THEREFORE...DECIDED TO KEEP AT LEAST A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS IN THE FORECAST INTO TUE MORNING. LOOKING AT SATELLITE...RADAR AND PRESSURE TRENDS AND IT LOOKS LIKE THE RIDGE...CENTERED TO OUR NE...HAS ALREADY BEGUN TO MOVE OUT. MOISTURE RETURN HAS ALREADY BEGUN AS FRONT TO OUR S HAS ALL BUT DISSIPATED. THERE HAS BEEN PLENTY OF HEAVY RAIN WELL TO OUR S TODAY AND EVEN ACROSS OUR AREA...EVEN AT THIS HOUR...THERE IS SOME HEAVY RAIN FALLING ACROSS SMALL PORTIONS OF ROBESON...DILLON AND MARLBORO COUNTIES. SOME OF THE HIGHER RESOLUTION MODELS ARE PICKING UP ON THIS AND INDICATING ISOLATED CONVECTION BUILDING BACK TO THE N WHILE ALSO MOVING IN FROM OFF THE WATER OVERNIGHT. WE HAVE ACCEPTED THESE TRENDS AND ADJUSTED THE FORECAST ACCORDINGLY. GIVEN THIS SCENARIO... THERE WILL BE MUCH MORE IN THE WAY OF CLOUDINESS TONIGHT WHICH WILL NOT ALLOW FOR AS MUCH COOLING AS WE EARLIER THOUGHT. THUS...LOWS HAVE BEEN RAISED TO THE LOWER TO MID 70S WITH UPPER 70S AT THE BEACHES. && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...MOISTURE FOCUSED ALONG LINGERING FRONT TO THE SOUTH WILL RETURN NORTH AS HIGH PRESSURE RETREATS TO THE NORTHEAST AND DEEPER RETURN FLOW SETS UP BETWEEN DEVELOPING LEE SIDE TROUGH INLAND AND BERMUDA HIGH PRESSURE OFF SHORE THROUGH MID WEEK. THIS DEEPER MOISTER RETURN FLOW WILL BRING PCP WATER VALUES UP AROUND 2 INCHES BY TUES AFTN. THIS WILL LEAD TO GREATER INSTABILITY ACROSS THE AREA WITH BETTER CHC OF LOCALIZED SHWRS AND THUNDERSTORMS FOCUSED ALONG CONVERGENT SEA BREEZE BOUNDARY...PIEDMONT TROUGH INLAND AND ANY OTHER BOUNDARIES THAT DEVELOP. THE MID TO UPPER RIDGE MAY HOLD OVER AREA THROUGH TUES BEFORE SLIPPING OFF SHORE BY WED. THIS SHOULD HELP TO INHIBIT STRONGER CONVECTION THROUGH TUES. GFS SHOWS A MINOR PERTURBATION RIDING THROUGH EARLIER ON WED AND THEN SOME SUBSIDENCE BEHIND IT FOR WED AFTN. ALWAYS TOUGH TO TIME THESE FINE FEATURES. FOR NOW THINKING IS THAT WE SHOULD SEE BETTER MOISTURE AND LIFT OVER INLAND AND SC AS WINDS COME AROUND TO THE SE-S THROUGH THE DAY ON TUES. BY WED A BETTER SW-W RETURN FLOW WILL SET UP WHICH SHOULD LEAD TO GREATER CHC OF SHWRS/TSTMS CLOSER TO THE COAST INITIALLY IN A MORE PINNED SEA BREEZE AND THEN CARRIED EAST INTO OUR AREA LATER IN THE DAY FROM PIEDMONT TROUGH ACTIVITY. OVERALL EXPECT GREATER CHC OF CONVECTION THROUGH MID WEEK. THE GREATER NE ON SHORE COMPONENT TO THE FLOW WILL KEEP TEMPS SLIGHTLY LOWER NEAR THE COAST ON TUES WITH TEMPS WARMEST OVER INLAND SC...UP AROUND 90. BY WED...THE W-SW COMPONENT TO FLOW WILL HELP TO PRODUCE MORE WIDESPREAD TEMPS CLOSER TO 90. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 PM MONDAY...PERSISTENCE THE RULE DURING THE EXTENDED AS BERMUDA HIGH PRESSURE AND GRADUALLY AMPLIFYING MID-LEVEL FLOW PRODUCE WARM AND UNSETTLED CONDITIONS. THE BERMUDA HIGH OFFSHORE WILL CONTINUOUSLY PUMP WARM/MOIST SW RETURN FLOW INTO THE CAROLINAS...WHILE ZONAL-FLOW-TRANSITIONING-TO-RIDGING ALOFT WILL HELP KEEP TEMPS ABOVE NORMAL. MEX NUMBERS FLUCTUATE BY ONLY 1-2 DEGREES THE ENTIRE LONG TERM...HENCE THE PERSISTENCE FORECAST...AND THERE IS GOOD CONFIDENCE FOR HIGHS IN THE 90S AND LOWS IN THE 70S EACH DAY. ADDITIONALLY...THU/FRI WILL FEATURE SCATTERED TO NUMEROUS SHOWERS/TSTMS...BEFORE SOME SUBSIDENCE ALOFT BEGINS TO LIMIT CONVECTIVE COVERAGE FOR THE WKND. WILL NOTE THAT THE ECMWF/GFS DIVERGE BY 180 DEGREES IN THE LONGWAVE PATTERN NEXT WKND AS THE FORMER DEVELOPS A CUTOFF LOW NEAR NEW ENGLAND. THIS IS A NEW SOLUTION AND NOT SUPPORTED...SO WILL CONTINUE WITH THE EXTENDED MOSTLY UNCHANGED FROM PREVIOUS FORECASTS. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 06Z...WITH RAIN DURING THE LATE EVENING VISIBILITIES WILL START TO COME DOWN AT LBT TO MVFR WITH THE OTHER TERMINALS AT VFR FOR NOW. HAVE MENTION OF MVFR AT OTHER TERMINALS AS LOW CLOUDS AND SHOWERS OFF THE COAST WORK THEIR WAY TO THE COAST. HIGH RESOLTION WRF AND HRRR SHOW PRECIPITATION WORKING ONTO THE COAST OF SC AND MOVING INTO THE MYRTLES BEFORE SUNRISE AND INTO ILM AFTER SUNRISE. MODELS HAD A GOOD HANDLE ON LAST NIGHTS PRECIPITATION SO WILL PAY ATTENTION AND INTRODUCE THE PRECIPITATION. THIS IS A BIG CHNAGE FROM THE 00Z TAFS AND HAVE ALSO MENTION CONVECTION ACROSS THE INLAND TERMINALS DURING THE AFTERNOON AS WELL. POPS HAVE INCREASED FROM THESE MODELS AND MOIST FLOW OFF THE OCEAN WITH A WEAK FRONTAL BOUNDRY TO OUR SOUTH AND A WEAK VORT MAX MOVING ACROSS THE REGION SHOULD ALL INTERACT TO INCREASE THE CHANCE OF PRECIPITATION ACROSS THE REGION THROUGHOUT THE EARLY MORNING HOURS AND INTO THE AFTERNOON. TERMINALS WILL BOUNCE BETWEEN VFR AND MVFR THROUGHOUT THE DAY WITH NO REAL GOOD FEEL ON WHEN THIS WILL OCCUR. WINDS WILL VEER FROM THE E TO THE SE ALONG THE COASTAL TERMINALS DURING THE MORNING WITH THE SEA BREEZE FRONT REACHING THE INLAND TERMINALS DURING THE AFTERNOON AND ENHANCING LIFT AND MOISTURE. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1 AM TUESDAY...HIGH PRESSURE CENTERED TO OUR NE WILL CONTINUE TO SHIFT AWAY FROM THE AREA THROUGH TUE. WINDS WILL BE E TO ESE INTO TUE MORNING. THE HIGHEST WIND SPEEDS...SUSTAINED UP TO 15 KT LATE THIS EVE...WILL SLOWLY DIMINISH TO 10 KT OR LESS BY MORNING. SEAS WILL RANGE FROM 2 TO 3 FT. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...HIGH PRESSURE WILL RETREAT TO THE NORTHEAST AS PIEDMONT TROUGH SETS UP ACROSS INLAND CAROLINAS AND BERMUDA HIGH REMAINS OFF TO THE EAST. ON SHORE NORTHEAST TO EAST FLOW OVER THE WATERS EARLY TUE WILL SLOWLY VEER TO THE SOUTHEAST TO SOUTH WITH SOUTHERLY RETURN FLOW SETTING UP THROUGH MID WEEK. GRADIENT WILL REMAIN ON THE WEAK SIDE TUES WITH LAND/SEA BREEZE INTERACTIONS AND OVERALL SPEEDS 10 TO 15 KTS OR LESS. SOUTHWEST FLOW WILL INCREASE CLOSER TO 15 KT LATER ON WED INTO WED NIGHT AS GRADIENT TIGHTENS BETWEEN BERMUDA HIGH TO THE EAST AND MORE PRONOUNCED TROUGH INLAND. SEAS 2 TO 3 FT TUE WILL INCREASE TO 2 TO 4 FT BY WED NIGHT. LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 300 PM MONDAY...LARGE HIGH PRESSURE OFFSHORE WILL MAINTAIN ITS LOCAL INFLUENCE INTO THE WEEKEND. THIS CREATES PERSISTENT SW WINDS OF 10-15 KTS WITH LITTLE FLUCTUATION THROUGH THE PERIOD. A 10 SEC SE GROUND SWELL WILL SLOWLY AMPLIFY ON THE PROLONGED FETCH AROUND THIS HIGH PRESSURE...BUT THE 2-3 FT SIGNIFICANT SEAS WILL BE PRIMARILY CREATED VIA 5 SEC SW WIND WAVES. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...RJD/MJC SHORT TERM...RGZ LONG TERM...JDW AVIATION...MAC/MJC
AREA FORECAST DISCUSSION
NWS TULSA OK
1142 PM CDT MON JUN 23 2014 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. AREAS OF FOG EXPECTED TO DEVELOP OVERNIGHT...WITH IFR VSBYS/CIGS POSSIBLE AT KFYV/KXNA. CONDITIONS SHOULD IMPROVE BY 14-15Z. && .PREV DISCUSSION... /ISSUED 925 PM CDT MON JUN 23 2014/ ..UPDATE... DISCUSSION... PRECIP HAS FOR THE MOST PART SHIFTED EAST OF THE CWA THIS EVENING. THE REMAINING FEW SHOWERS WERE LOCATED ACROSS FAR EASTERN OKLAHOMA INTO PARTS OF NORTHEAST OKLAHOMA. THESE SHOWERS SHOULD CONTINUE TO DISSIPATE AND SHIFT EASTWARD OVER THE NEXT FEW HOURS. ACROSS THE REST OF EASTERN OKLAHOMA...SKIES WERE CLEARING OUT WITH LIGHT WINDS OBSERVED. OVERNIGHT TONIGHT...MOSTLY CLEAR TO PARTLY CLOUDY SKIES SHOULD BE COMMON ACROSS THE REGION. LATEST LOCAL IN-HOUSE MODEL AND THE HRRR CONTINUE TO INDICATE THAT THE CONVECTION OVER EASTERN COLORADO AND THE TEXAS PANHANDLE SHOULD STAY TO THE NORTH AND WEST OF THE REGION. THUS...WILL NOT CARRY POPS AFTER 06Z. THE LIGHT WINDS AND MOSTLY CLEAR TO PARTLY CLOUDY SKIES WILL HOWEVER CREATE THE POTENTIAL FOR AREAS OF FOG TO BE POSSIBLE AFTER THE RECENT RAINS. HAVE EXTENDED THE FOG POTENTIAL A BIT FURTHER WEST AND SOUTH ACROSS THE REGION. TEMPERATURES OVERNIGHT LOOK TO BE COOLER COMPARED TO PREVIOUS NIGHTS AND HAVE ONLY MADE A FEW TWEAKS FOR THE EVENING UPDATE. && .PRELIMINARY POINT TEMPS/POPS... TUL 63 89 67 88 / 10 10 20 30 FSM 65 89 67 90 / 20 10 20 30 MLC 64 89 68 89 / 10 10 20 30 BVO 61 88 64 86 / 10 10 20 30 FYV 60 85 61 85 / 20 10 20 30 BYV 61 85 61 86 / 20 10 20 30 MKO 62 88 66 87 / 10 10 20 30 MIO 61 86 64 86 / 10 10 20 30 F10 63 88 67 87 / 10 10 20 30 HHW 66 89 69 90 / 10 10 20 30 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...99 LONG TERM....99 AVIATION...18
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
411 AM CDT TUE JUN 24 2014 .DISCUSSION... 08Z/3AM SURFACE ANALYSIS SHOWED A STATIONARY BOUNDARY IN PLACE FROM SULPHUR SPRINGS TO BURLESON TO BRECKENRIDGE. THERE WERE WEAK GRADIENTS OF BOTH TEMPERATURE AND DEW POINT ALONG THE BOUNDARY WITH COOLER VALUES LOCATED NORTH OF THE BOUNDARY. LOOKING AT THE GRADIENT OF EITHER TEMPERATURE OR DEW POINT ALONG THIS BOUNDARY IS NOT VERY IMPRESSIVE...HOWEVER...OBJECTIVE ANALYSIS INDICATES THAT THIS RESULTS IN A FAIRLY TIGHT GRADIENT OF THETA-E WITH A CHANGE OF ALMOST 8 KELVIN FROM NORTH TO SOUTH ALONG THIS BOUNDARY. AS A RESULT...THINK THAT THIS BOUNDARY WILL HANG AROUND THROUGH AT LEAST THE MORNING HOURS OF THE DAY TODAY. IT MAY HOLD SOME IDENTITY INTO THE AFTERNOON HOURS AS WELL IF SHORT RANGE MODEL GUIDANCE IS ACCURATE. THE 07Z RAP INDICATED THAT THIS BOUNDARY EXTENDS UP TO THE 850 MB LEVEL WHERE THE THETA-E GRADIENT IS EVEN MORE PRONOUNCED...SHOWING A THETA-E CHANGE OF 12-16 KELVIN ALONG THE BOUNDARY THROUGH THIS MORNING. THE MAIN POINT OF THIS ANALYSIS IS THAT THIS BOUNDARY APPEARS AS THROUGH IT IS STRONG ENOUGH TO REMAIN SOMEWHERE IN THE CWA AS WE APPROACH THE PEAK HEATING HOURS OF THE DAY. IF IT STILL EXISTS THIS AFTERNOON...IT COULD BE A BIG PLAYER IN THUNDERSTORM INITIATION TODAY. REGARDING THUNDERSTORM CHANCES FOR TODAY...ALMOST ALL GUIDANCE INDICATES THAT THIS BOUNDARY IS IMPORTANT FOR THUNDERSTORM CHANCES TODAY AS MOST GUIDANCE ADVERTISES QPF ALONG THIS BOUNDARY SOMETIME THIS MORNING THROUGH THIS AFTERNOON. THE TIMING OF WHEN THIS QPF SHOWS UP IS THE KEY DIFFERENCE AMONGST THE MODELS. MANY OF THE HIGH-RESOLUTION MODELS SHOW QPF OR SIMULATED REFLECTIVITY DEVELOPING ALONG THIS BOUNDARY JUST AFTER SUNRISE THIS MORNING. IF THIS OCCURS...THE CONVECTION THAT IS INITIATED WILL PROBABLY BE RELATIVELY WEAK IN NATURE AND MAY BE SOMEWHAT ELEVATED AS MOSTLY CLEAR SKIES TONIGHT OVER THE BOUNDARY HAS ALLOWED A NICE NOCTURNAL INVERSION TO SET UP OVER THE AREA. IT`S HARD TO SAY WHETHER THIS CONVECTION WOULD BE ENOUGH TO IMPACT THE BOUNDARY OR NOT IF IT DEVELOPS THIS MORNING. IF NOTHING ELSE...IT WILL ADD CLOUDS OVER THE WARMER SIDE OF THE BOUNDARY ALLOWING DIFFERENTIAL HEATING TO REDUCE THE IDENTITY OF THE BOUNDARY BY WARMING THE COOL SIDE AND KEEPING THE WARM SIDE SHIELDED FROM SUNSHINE/HEATING. IT`S PROBABLY FOR THIS REASON THAT MOST HIGH RESOLUTION GUIDANCE MEMBERS HAVE MORNING CONVECTION ALONG AND SOUTH OF THIS BOUNDARY WITH LITTLE TO NO ADDITIONAL PRECIPITATION THIS AFTERNOON. IF THERE IS LITTLE TO NO ACTIVITY ALONG THE BOUNDARY THIS MORNING...THIS BOUNDARY PROBABLY HAS A BETTER CHANCE AT INITIATING STRONG THUNDERSTORMS ACROSS NORTH OR CENTRAL TEXAS THIS AFTERNOON. HIGH RESOLUTION GUIDANCE IS USUALLY FAIRLY RELIABLE WHEN CONSISTENTLY SHOWING A SIMULATED REFLECTIVITY SIGNAL OF THUNDERSTORM INITIATION ALONG A COMMON BOUNDARY AROUND A COMMON TIME. THEREFORE...THERE MAY BE A SLIGHTLY BETTER CHANCE THAT STORMS DEVELOP ALONG THE BOUNDARY THIS MORNING RATHER THAN HOLDING OFF UNTIL THIS AFTERNOON. THE ONLY REASON TO DOUBT SOME OF THE MODELS SHOWING THIS MORNING CONVECTION IS THE LACK OF RESPONSE IN THE REST OF THE MASS FIELDS WHERE THE QPF IS LOCATED. THAT IS...SOME POSITIVE QPF SHOWS UP SOUTH OF THE BOUNDARY...THIS SEEMS TO MAKE SENSE...HOWEVER THERE IS NO INCREASE IN MID-LEVEL RELATIVE HUMIDITY AND NO LOW-LEVEL RESPONSE IN THE WIND FIELDS. BRINGING MODEL LOGIC INTO THE REAL WORLD...THAT`S LIKE SAYING...WE`RE GOING TO HAVE RAIN...BUT NO CLOUDS. IT DOESN`T MAKE SENSE. AS A RESULT...IT IS POSSIBLE THAT THE MODELS ARE SIMPLY PUTTING QPF OUT THERE BECAUSE THERE`S A BOUNDARY AND WE HAVE SOME MOISTURE AND CAPE IN PLACE SOUTH OF THE BOUNDARY. FOR MODELS THAT DO NOT SHOW MUCH ACTIVITY ALONG THE BOUNDARY THIS MORNING...THOSE SOLUTIONS REALLY RAMP UP THE CAPE AND MOISTURE POOLING SOUTH OF THIS BOUNDARY THIS AFTERNOON. THOSE MODELS INDICATE LOWER TO MID-70S DEW POINTS POOLING UP JUST SOUTH OF THE DFW AREA THIS AFTERNOON...RESULTING IN OVER 4000 J/KG OF CAPE. GRANTED...THERE IS VERY WEAK WIND SHEAR...SO EVEN IF STORMS DEVELOP IN THIS ENVIRONMENT THEY PROBABLY WILL NOT BE VERY ORGANIZED. THAT SAID...ANY STORMS THAT DEVELOP WITH 4000 J/KG OF CAPE WILL GET BIG...FAST. LOCALLY HEAVY RAINFALL AND MICROBURSTS WOULD BE THE PRIMARY HAZARDS IF THIS SCENARIO PANS OUT. ALSO...IF THUNDERSTORMS DO NOT DEVELOP THIS MORNING...THE BOUNDARY WILL PROBABLY MOVE A BIT WITH THE WESTERN PART OF THE BOUNDARY MOVING NORTH. IN THIS SCENARIO THE BOUNDARY WILL BE LOCATED NEAR A BOWIE TO GRAPEVINE TO EMORY LINE BEFORE THUNDERSTORMS ARE MOST LIKELY TO DEVELOP. WITH WATER VAPOR SATELLITE IMAGERY SHOWING A COUPLE OF WEAK SHORTWAVE TROUGHS OVER COLORADO AND NEW MEXICO EARLY THIS MORNING...WENT AHEAD AND BUMPED UP POPS A BIT FOR THIS AFTERNOON JUST IN CASE THIS SCENARIO PANS OUT. THIS FORECAST PROBLEM SHOULD AT LEAST BE FAIRLY EASY TO FIGURE OUT TODAY...IF WE END UP WITH SCATTERED STORMS ALONG THE BOUNDARY THAT PERSIST FOR AT LEAST A FEW HOURS THIS MORNING...WE HAVE A BETTER CHANCE AT WASHING OUT OUR BOUNDARY...MAKING AFTERNOON THUNDERSTORM CHANCES LESS LIKELY. IF THERE IS BRIEF OR NO THUNDERSTORM ACTIVITY ALONG THE BOUNDARY THIS MORNING...WE COULD SEE SOME SCATTERED STRONG STORMS DEVELOP ACROSS MUCH OF NORTH AND CENTRAL TEXAS THIS AFTERNOON. HAVE POPS IN THE 20 TO 50 PERCENT RANGE TODAY DUE TO UNCERTAINTY WITH REGARDS TO HOW TODAY WILL PLAY OUT. BY LATE THIS AFTERNOON...MOST MODELS HAVE THIS BOUNDARY GETTING WASHED OUT BY PERSISTENT SOUTHERLY FLOW AND STRONG DAYTIME HEATING. FOR TONIGHT...IF WE GET A LARGE CLUSTER OF STORMS TO PERSIST THIS AFTERNOON...WE COULD SEE SOME OF THIS ACTIVITY CONTINUE ACROSS THE CWA THROUGH THE OVERNIGHT HOURS. ANY LINGERING SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE MUCH WEAKER THAN THIS AFTERNOON. OTHERWISE...IF NOTHING GETS GOING THIS AFTERNOON...OUR ATTENTION THEN TURNS TO THE HIGH PLAINS WHERE HIGH RESOLUTION MODELS CONSISTENTLY SHOW A SQUALL LINE ORGANIZING LATE TONIGHT. IF THE SQUALL LINE BECOMES STRONG ENOUGH...IT WILL CREATE ITS OWN MINI- WEATHER SYSTEM THAT COULD PROPAGATE IT SOUTHEAST OVER NORTH TEXAS BY EARLY WEDNESDAY MORNING. CONFIDENCE IN THIS IS NOT AS GREAT AS IT WAS FOR YESTERDAY MORNING...MAINLY BECAUSE LOW-LEVEL SHEAR IS SOMEWHAT LACKING IN MOST MODEL SOLUTIONS. LOW-LEVEL WIND SHEAR IS ONE OF THE KEY FACTORS THAT HELPS BALANCE COLD-POOL STRENGTH AND REALLY HELPS LINEAR CONVECTIVE SYSTEMS BECOME ORGANIZED INTO THEIR OWN MINI-WEATHER SYSTEM. IN THE ABSENCE OF STRONGER LOW-LEVEL SHEAR...THESE STORM COMPLEXES STILL BECOME QUITE STRONG WHERE THEY ORIGINATE...BUT TEND TO LOSE THEIR COLD POOLS AND DISSIPATE WHEN THEY BEGIN TO PROPAGATE AWAY FROM THE HIGH PLAINS. BECAUSE OF THE LACK OF BETTER LOW-LEVEL SHEAR...ONLY WENT WITH 30 POPS FOR THIS POSSIBILITY FOR THE FAR NORTHWESTERN CWA EARLY WEDNESDAY MORNING. WEDNESDAY...MODELS ARE FAIRLY CONSISTENT IN BRINGING A SHORTWAVE TROUGH SOUTH ACROSS THE RED RIVER TOMORROW AFTERNOON. ASSUMING THIS PANS OUT...EXPECT SCATTERED THUNDERSTORMS TO DEVELOP NORTH OF INTERSTATE 20 TOMORROW AFTERNOON AND THEN MOVE SOUTHEAST IN THE WEAK NORTHWEST FLOW ALOFT. ALSO...MODELS ARE SHOWING A FAIRLY CONSISTENT SIGNAL OF A STRONGER THAN NORMAL SEA-BREEZE BOUNDARY MOVING NORTH FROM THE GULF COAST TOMORROW. AT LEAST THAT`S WHAT IT LOOKS LIKE IN THE MID-LEVEL RELATIVE HUMIDITY FIELDS. AT ANY RATE...WITH THE CONSISTENCY OF MODELS SHOWING QPF...WITH CLOUDS...MOVING IN FROM THE GULF COAST TOMORROW AFTERNOON...WENT AHEAD AND KEPT SOME HIGHER POPS OVER THE SOUTHEASTERN CWA. THURSDAY...MODELS CONTINUE TO SHOW THAT THE WEDNESDAY SHORTWAVE TROUGH WILL SORT OF MEANDER SOUTH AND JUST BECOME A GENERAL WEAKNESS ALOFT STUCK IN BETWEEN UPPER LEVEL RIDGES TO OUR WEST AND EAST. MODELS ARE SHOWING THAT THE WESTERN RIDGE WILL BEGIN TO AMPLIFY A BIT THURSDAY AFTERNOON...POSSIBLY SPREADING SOME FORCING FOR SUBSIDENCE OVER THE FAR WESTERN CWA. AS A RESULT...KEPT HIGHEST POP CHANCES FOR THURSDAY ALONG AND EAST OF INTERSTATE 35 AS THIS IS FURTHER REMOVED FROM THE RIDGE AND STILL WELL WITHIN THE MODEL CONSENSUS LOCATION OF THE COL/UPPER LEVEL WEAKNESS AREA. WE WILL STILL HAVE PLENTY OF MOISTURE WITH LITTLE CAP IN PLACE FOR AFTERNOON THUNDERSTORM CHANCES EAST OF INTERSTATE 35...SO KEPT POPS IN THE 30-40 PERCENT RANGE AT THIS TIME. FRIDAY THROUGH EARLY NEXT WEEK...THE GFS CONTINUES TO SHOW THAT A STRONG WEST COAST UPPER TROUGH WILL MOVE EASTWARDS OVER THE ROCKIES BY FRIDAY AFTERNOON. THE GFS HAS BEEN SHOWING THIS RESULTING IN LAYING THE NORTHERN MEXICO UPPER RIDGE OVER NORTH TEXAS BY FRIDAY...AND HOLDING IN PLACE THROUGH THE UPCOMING WEEKEND. THERE ARE STILL SOME MODEL SOLUTIONS THAT INDICATE THAT UPPER LEVEL RIDGING WILL STAY WEST RESULTING IN A PERSISTENT WEAKNESS ALOFT OVER PARTS OF THE AREA THIS WEEKEND...HOWEVER THE GFS HAS BEEN EXTREMELY CONSISTENT WITH THIS SOLUTION...AND AS RESULT WAS RELIED UPON HEAVILY IN THIS FORECAST. THE GFS HAS UPPER LEVEL RIDING IN PLACE OVER NORTH TEXAS FROM FRIDAY THROUGH THE MIDDLE OF NEXT WEEK...WITH RIDGING ONLY INCREASING IN INTENSITY EARLY NEXT WEEK. WENT WITH A DRY FORECAST FOR THE ENTIRE CWA DURING THIS PERIOD AS A RESULT. ALSO WENT AHEAD AND GRADUALLY RAISED TEMPERATURES THROUGH THIS PERIOD. IF THIS VERIFIES...WE MAY GET INTO OUR FIRST 100 DEGREE HIGHS HERE BY TUESDAY OR WEDNESDAY OF NEXT WEEK. THAT`S A LONG WAYS OUT OF COURSE...BUT THE PATTERN LOOKS HOT AND DRY FOR NOW. CAVANAUGH && .AVIATION... /ISSUED 1140 PM CDT MON JUN 23 2014/ /6Z TAFS/ VFR CONDITIONS PREVAIL ACROSS NORTH TEXAS TONIGHT WITH AREA WINDS LIGHT AND VARIABLE IN MOST LOCATIONS. THERE ARE A COUPLE OF REMNANT OUTFLOW BOUNDARIES THAT RESIDE ACROSS NORTH TEXAS. ONE IS VERY NEAR THE METROPLEX BASED ON EARLIER RADAR DATA...BUT THIS MAY BECOME SO DIFFUSE OVERNIGHT THAT IT IS A NON PLAYER IN ADDITIONAL SHOWER/TSTM DEVELOPMENT. THE OTHER MORE SIGNIFICANT BOUNDARY IS SOUTH OF THE MAJOR AIRPORTS...JUST SOUTH OF WACO. LATEST HIGH RESOLUTION GUIDANCE SUGGESTS THAT SCATTERED SHOWERS AND A FEW THUNDERSTORMS MAY DEVELOP ALONG THIS BOUNDARY LATE TONIGHT INTO TUESDAY MORNING. IT IS RATHER DIFFICULT TO PICK OUT ANY SIGNIFICANT UPPER DISTURBANCE BUT THUNDERSTORMS ARE ONGOING ACROSS WEST TEXAS AND IT MAKES SENSE THAT LIFT ASSOCIATED WITH THIS ACTIVITY WOULD CONTINUE TO SPREAD EAST. THE ENVIRONMENT REMAINS MODESTLY MOIST COMPARED TO THE LAST 24 HOURS...BUT IS STILL VERY WEAKLY CAPPED...SO ANY FORCING WITH THE BOUNDARY IN THE VICINITY MAY IGNITE SOME SHOWERS/STORMS. WILL HAVE A VCSH IN AT WACO FROM 11-16Z TO ADDRESS THIS POSSIBILITY. IF SHOWERS/STORMS DO DEVELOP QUICKLY TONIGHT...THIS TIMING/IMPACT WOULD NEED TO BE AMENDED. OTHERWISE...VFR CONDITIONS SHOULD GENERALLY PREVAIL WITH WINDS BECOMING MORE SOUTHERLY ON TUESDAY. THERE WILL REMAIN THE CHANCE OF SCATTERED AFTERNOON SHOWERS AND THUNDERSTORMS ON TUESDAY. THIS CHANCE WILL BE A LITTLE HIGHER TUESDAY THAN ON MONDAY...GIVEN THAT THERE WILL LIKELY NOT BE ANY STRONG SUBSIDENCE BEHIND A COMPLEX OF STORMS LIKE THERE WAS ON MONDAY. && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 92 75 93 75 91 / 40 30 40 20 30 WACO, TX 88 73 90 73 92 / 50 30 50 20 30 PARIS, TX 91 72 90 72 89 / 30 20 40 20 40 DENTON, TX 91 73 91 73 91 / 30 30 40 20 30 MCKINNEY, TX 92 74 92 74 91 / 30 30 40 20 40 DALLAS, TX 92 75 92 74 91 / 40 30 40 20 40 TERRELL, TX 93 76 93 76 92 / 50 30 30 20 40 CORSICANA, TX 89 73 90 73 91 / 50 30 50 20 40 TEMPLE, TX 90 72 90 73 90 / 40 30 50 20 30 MINERAL WELLS, TX 89 72 90 71 90 / 50 40 30 20 20 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ /
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1112 PM CDT MON JUN 23 2014 .AVIATION... /06Z TAFS/ Stratus will develop along the I-10 corridor during the morning hours Tuesday, going with MVFR CIGS at the KSOA and KJCT terminals after 10Z Tuesday. VFR conditions will return by 15Z Tuesday. Keeping the other terminals VFR the next 24 hours. A complex or two of storms have developed over southeast New Mexico and the Big Bend region. However, these storms will propagate southeast over the Permian Basin and Trans Pecos through the early morning hours and stay west of the terminals. && .PREV DISCUSSION... /ISSUED 1028 PM CDT MON JUN 23 2014/ UPDATE... An outflow boundary continues to move southwest across the Concho Valley and North Edwards Plateau late this evening. Isolated thunderstorms that developed along this boundary earlier this evening have dissipated with the loss of heating. The main concern for the rest of tonight will be the potential for showers and thunderstorms to move in from the west towards daybreak. Thunderstorms are currently affecting portions of eastern New Mexico, with the strongest convection located across southeast New Mexico north of Carlsbad. Uncertainty exists regarding convective evolution and weather storms will organize into a southeast propagating MCS overnight. The Texas Tech WRF is the most aggressive model and brings a weakening band of convection into western sections after 4 AM, with activity dissipating across central sections through early morning. The latest NAM and HRRR show most of the convection remaining west of the forecast area. Given the uncertainty, kept chance POPs in the forecast generally west of a Haskell to Sonora line overnight and lowered POPs to slight chance elsewhere. Also tweaked temps and dewpoints to account for trends. PREV DISCUSSION... /ISSUED 618 PM CDT MON JUN 23 2014/ AVIATION... /00Z TAFS/ Expect VFR conditions at the terminals this evening into the early morning hours. Stratus will develop along the I-10 corridor during the morning hours Tuesday, going with MVFR CIGS at the KSOA and KJCT terminals after 10Z Tuesday. VFR conditions will return by 15Z Tuesday. Isolated thunderstorms will be possible around the KSJT terminal through mid evening and carrying VCTS through 03Z. A complex or two of storms will develop well west of the terminals later tonight and some of this activity may make it east into West Central Texas by Tuesday morning. Confidence is not high enough to put in the terminals and will watch radar and satellite trends this evening. PREV DISCUSSION... /ISSUED 344 PM CDT MON JUN 23 2014/ SHORT TERM... (Tonight and Tuesday) Showers and thunderstorms moved out of the area early this afternoon, leaving partly to mostly cloudy skies and a very humid air mass along with leftover outflow boundaries from the overnight into early morning thunderstorms. Aloft, a shortwave trough is moving east into New Mexico this afternoon helping to set off thunderstorms across the mountains of New Mexico. Thunderstorms were also developing across the mountains near and west of the Big Bend area in Texas. A few isolated thunderstorms could develop by late this afternoon or evening along some of the previously mentioned boundaries. For tonight, expect another cluster of thunderstorms to get organized to our west or northwest and move into our area overnight. Thunderstorms are already developing across the mountains of New Mexico, and upscale growth into a cluster of thunderstorms is expected as the shortwave moving into the area approaches. Several models indicate an MCS moving east through the Permian Basin overnight, and into our area by early tomorrow morning. Timing the arrival of these thunderstorms is difficult, but expect the bulk of the activity to be after midnight rather than before. Locally heavy rainfall, and dangerous lightning would be the primary concerns with these thunderstorms. Additional thunderstorm activity is possible tomorrow afternoon, especially if the atmosphere can destabilize during the afternoon hours. The favored area for redevelopment tomorrow appears to be northwest of the area near the Texas panhandle region where another approaching shortwave will interact with persistent moist upslope flow. Temperatures will remain near normal with lows near 70 tonight, highs around 90 tomorrow. 20 LONG TERM... (Tuesday night through next Monday) Weak northwest flow aloft will continue over our area Tuesday night and Wednesday. Could have a leftover disturbance (possibly a MCV) over our eastern counties Tuesday evening and early Tuesday night. The NAM brings a weak upper level disturbance southeast across the TX Panhandle and toward our far northern counties by early Wednesday morning. Showers and thunderstorms would be possible with both of these features. With this in mind, carrying 30 PoPs across our eastern and far northern counties Tuesday night, with 20 PoPs elsewhere. Have a lingering low PoP for the eastern part of our area on Wednesday, which will be on the eastern periphery of the upper level high. On Thursday and Friday, the upper high will remain positioned over Mexico and the U.S. Desert Southwest, with an eastward extension to near the Big Bend region. An upper shear axis is progged to set up to the east of our area. Cannot rule out a low possibility of showers/thunderstorms in some of our northern or eastern counties Thursday and Friday. However, with lack of confidence in placement of weak disturbances aloft or surface boundaries, prefer to leave PoPs out for now. For the weekend into the first part of next week, the 12Z GFS and ECMWF are in better agreement in gradually building the heights aloft over our area. While specific differences still exist, both models show an overall shift with the upper high to the north across the Southwestern states, while expanding it to the east into Texas and the Southern Plains. This would effectively shut off rain chances for our area, and lead to a warming trend in temperatures. However, with fairly moist ground conditions and evapotranspirative effects, along with south-southeasterly low- level flow keeping an influx of Gulf moisture into our area, believe the warming trend will be tempered. In addition, the GFS keeps the low-level thermal ridge to our west, with only a limited eastward expansion. With these indications, going with highs below the GFS MOS guidance for our area. 19 && .PRELIMINARY POINT TEMPS/POPS... Abilene 71 90 72 92 72 / 20 40 20 20 10 San Angelo 70 90 71 92 72 / 30 30 20 10 5 Junction 71 89 71 91 72 / 20 20 20 20 5 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
139 AM EDT TUE JUN 24 2014 .SYNOPSIS... A WEAK AREA OF HIGH PRESSURE OFF THE COAST OF NEW ENGLAND WILL DRIFT EAST DURING THE NEXT COUPLE OF DAYS AS LOW PRESSURE ADVANCES SLOWLY FROM OUT OF THE MIDWEST. SOUTHERLY FLOW BETWEEN THE SYSTEMS WILL PULL IN INCREASINGLY MOIST AIR BACK INTO THE MID APPALACHIAN AND MID ATLANTIC REGION INTO MID WEEK...MAINTAINING A DAILY THREAT FOR SHOWERS AND THUNDERSTORMS. && .NEAR TERM /THROUGH TODAY/... AS OF 845 PM EDT MONDAY... CONVECTION HAS BEEN LACKING FOR A CHANGE THIS EVENING AS THE COMBO OF THE RESIDUAL WEAK WEDGE...LACK OF UPPER FORCING AND ONLY WEAK INSTABILITY CONTINUES TO KEEP SHOWERS LIMITED TO THE EXTREME WEST/SW. THIS IN AN AREA OF RETURN SE FLOW AS BETTER LIFT REMAINS WELL TO THE WEST AHEAD OF THE NEXT FRONT. LATEST HRRR TRIES TO SNEAK A FEW SHRA/TSRA IN FROM THE SOUTH ACROSS NW NC/SW VA IN THE NEXT FEW HOURS AND ALONG THE SOUTHERN BLUE AFTER MIDNIGHT. HOWEVER THIS LOOKS IFFY GIVEN CURRENT TRENDS...SO HAVE ALREADY REMOVED MOST POPS EARLY THIS EVENING...BUT WILL KEEP IN CHANCE POPS SW OVERNIGHT ESPCLY THE NW N CAROLINA MOUNTAINS/FOOTHILLS PER DEEPER UPSLOPE FLOW AND LINGERING WEAK INSTABILITY. DO EXPECT THE WEDGE TO FLOP BACK TO THE WEST WITH CURRENT STRATO- CU ALONG THE BLUE RIDGE LIKELY TO LOWER AND EXPAND FURTHER AFTER MIDNIGHT UNDER A WEAK BUT MORE EASTERLY TRAJECTORY. ALSO SOME FOG AROUND BUT GIVEN LIGHT MIXING EARLY AND CLOUDS APPEARS ONLY PATCHY COVERAGE FOR THE MOST PART. LOW TEMPS ON TRACK WITH SOME SLIGHT DOWNWARD ADJUSTS IN THE VALLEYS...OTRW MOSTLY LOW/MID 60S LOOK GOOD. THE WEDGE SHOULD BE EAST OF THE AREA TUESDAY MORNING WITH A COLD FRONT AND ASSOCIATED SURFACE LOW OVER THE UPPER MISSISSIPPI VALLEY. THIS WILL PLACE THE AREA IN A WARM AND HUMID AIRMASS WITH PULSE STORMS SLOWLY TRACKING SOUTHWEST TO NORTHEAST STARTING IN THE MOUNTAINS BY LATE AFTERNOON AND EAST OF THE BLUE RIDGE BY MID AFTERNOON. INSTABILITIES WILL BE GREATER TOMORROW THEREFORE THE CHANCE FOR SEEING MORE STRONGER STORMS DEVELOPING COMPARED TO TODAY ARE GOOD. PWAT VALUES WILL ALSO INCREASE TOMORROW BUT HOVERING AROUND NORMAL FOR THIS TIME OF YEAR. WIDESPREAD FLASH FLOOD THREAT IS LOW WHILE LOCALIZED FLOODING IS ALWAYS POSSIBLE. TEMPERATURES WILL ALSO BE NEAR NORMAL TUESDAY. && .SHORT TERM /TONIGHT THROUGH THURSDAY/... AS OF 305 PM EDT MONDAY... ACTIVE PATTERN THROUGH WEDNESDAY EVENING...AS TROUGH AND ASSOCIATED SFC FRONT EDGE EAST INTO THE MTNS BY 18Z WED THEN SLOW DOWN AS IT ENCOUNTERS THE WRN ATLANTIC RIDGE. MODELS FAVOR EXITING THE SHORTWAVE AFTER MIDNIGHT WED NIGHT...THEN MODELS STILL BRING WEAK ENERGY INTO THE CENTRAL APPALACHIANS THURSDAY...WHILE FRONT STALLS OVER THE ERN VA/NC AREA. THINK THURSDAY WILL BE DRIER FOR MOST...BUT COULD SEE ENOUGH LINGERING MOISTURE AROUND AND WITH SOME CONVERGENCE IN THE LOW LVLS AT LEAST ISOLATED CONVECTION POSSIBLE. ATTM...WEDNESDAY WILL BE WETTER/STORMIER WITH 40-60 POPS...HIGHER IN THE NW CLOSER TO THE UPPER SUPPORT. THE STORM PREDICTION CENTER IS NOT HIGHLIGHTING ANY SVR THREAT. TIMING OF CLOUDS/STORMS MAY OFFSET LOW LVL INSTABILITY/LAPSE RATES...BUT CANNOT RULE OUT SOME ISOLATED SVR THREAT. TEMPS REMAIN TYPICAL OF LATE JUNE. BEHIND THE FRONT THURSDAY HUMIDITY LEVELS MAY SINK SOME...WITH DEWPOINTS DROPPING FROM THE MID 60S WEST TO UPPER 50S/LOWER 60S. THE EAST WILL STAY SOMEWHAT ELEVATED AS FRONTAL BOUNDARY LINGERS JUST EAST OF THE FORECAST AREA. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 155 PM EDT MONDAY... GOING TO SEE TYPICAL SUMMER PATTERN IN THE REGION THIS PERIOD. MOISTURE REMAINS ELEVATED IN THE LOW LVLS WITH WEAK WAVES ALOFT HARD TO PINPOINT EARLY ON TIMING WISE. RIDGE BUILDS INTO THE WEEKEND AND EARLY NEXT WEEK SUCH THAT THREAT OF STORMS WILL BE MAINLY IN THE AFTERNOON/EVENINGS. HOWEVER...CANNOT RULE OUT OVERNIGHT SHOWERS OR STORM THREAT GIVEN THE SW FLOW ALOFT AND LOW LVL MOISTURE CONVERGENCE. FRONTAL BOUNDARY EXISTS EARLY IN THE PERIOD FROM THE OHIO VALLEY INTO THE SOUTHEAST BUT WIND FIELDS ARE WEAK. STILL WILL SEE AT LEAST THE POPS IN THE 30-50 RANGE FOR FRI-SAT. TEMPS STAY ABOVE NORMAL AT NIGHT DUE TO THE MOISTURE CONTENT IN THE ATMOSPHERE...WHILE DAYTIME HIGHS STAY CLOSER TO WHAT WE EXPECT FOR LATE JUNE...WITH UPPER 70S HIGHER TERRAIN...LOWER TO MID 80S REST OF THE MOUNTAINS...AND MID 80S/NEAR 90 SOUTHEAST. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 135 AM EDT TUESDAY... REDEVELOPMENT OF WEAK WEDGE WILL SUPPORT GRADUAL EXPANSION AND LOWERING OF CLOUDS OVERNIGHT...WITH MOST TERMINAL FORECAST SITES EXPECTED TO DIP BACK INTO MVFR RANGE BEFORE DAYBREAK...WITH PATCHY AREAS OF IFR/LIFR EXPECTED IN LOW LYING AREAS AND/OR IN AREAS WHERE CLOUDS ARE MINIMIZED. ONSET OF STRONG DAYTIME HEATING AND LOW LEVEL WINDS VEERING INTO MORE OF A SOUTHERLY COMPONENT AS SURFACE RIDGE CONTINUES DRIFTING EAST AND AWAY FROM THE AREA IN ADVANCE OF APPROACHING UPSTREAM SHORT WAVE TROF SHOULD ALLOW FOR MORE PRONOUNCED WEAKENING OF WEDGE THIS AFTERNOON. THIS SHOULD ALLOW MVFR CEILINGS TO GRADUALLY LIFT BACK TO MAINLY BKN VFR CU CIGS BY LATE MORNING/EARLY AFTERNOON...ALONG WITH INCREASING THREAT OF WIDELY SCATTERED SHOWERS/THUNDERSTORMS...ESPECIALLY WEST OF THE BLUE RIDGE. WITH THIS IN MIND...MAINTAINED MENTION OF VCTS AT BOTH KBLF/KLWB BEGINNING AROUND 18Z/200 PM EDT. EXTENDED AVIATION DISCUSSION... NEXT UPPER TROUGH AND ITS ASSOCIATED COLD FRONT WILL APPROACH FROM THE WEST TUESDAY NIGHT INTO WEDNESDAY...WITH AN INCREASING THREAT FOR MORE WIDESPREAD SHOWERS AND STORMS WEDNESDAY AFTERNOON/EVENING. TIMING REMAINS A BIT IN QUESTION AS POTENTIAL EARLIER ARRIVAL COULD MEAN MORE COVERAGE IN THE EAST INCLUDING PERIODS OF MVFR/IFR IN STRONGER STORMS...WHILE BETTER CHANCE OF MORE WIDESPREAD LOWER CONDITIONS ACROSS THE ENTIRE REGION IF THE FRONT SLOWS. MAY SEE SOME IMPROVEMENT ON THURSDAY AS THE FRONT WASHES OUT OVERHEAD OR PUSHES TO THE SE...BUT STILL ENOUGH MOISTURE WITH HEATING FOR ADDED DIURNAL CONVECTION AGAIN THURSDAY AFTERNOON WITH PERIODS OF MVFR POSSIBLE. MOISTURE LIKELY RETURNS ON FRIDAY WITH A REPEAT OF MAINLY AFTERNOON/EVENING CONVECTION FRIDAY LEADING TO BRIEF PERIODS OF MVFR/IFR. THIS TREND LOOKS TO PERSIST AGAIN ON SATURDAY WITH AT LEAST ISOLATED CONVECTION MAKING FOR OCNL MVFR/IFR IN SPOTS SATURDAY AFTERNOON AND EVENING. OTRW AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE NIGHT/EARLY MORNING...PARTICULARLY IN AREAS THAT SEE RAIN THE PREVIOUS AFTERNOON. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...WERT/WP NEAR TERM...JH/RCS SHORT TERM...WP LONG TERM...WP AVIATION...JH/RCS/WERT Area Forecast Discussion National Weather Service Spokane WA 230 AM PDT TUE JUN 24 2014 .SYNOPSIS... Following the warmest weather of the season so far...temperatures will return to normal Tuesday with the arrival of a cold front. Tuesday`s cold front will also bring a good chance of showers and thunderstorms to the Inland Northwest as well as gusty winds. The Thursday through Sunday time frame will also feature a chance of showers and thunderstorms...and will once again accompany gusty winds. && .DISCUSSION... Today: Water vapor imagery at 2:00 AM this morning shows the back side of a cold front pushing across western WA. Out ahead of the front is a decent plume of moisture with Pwats up over an inch. Forcing along the front is not particularly strong, but radar is picking up on some light shower activity across the Cascade Mtns and out over as far east as the western basin. We are pretty dry at low levels, so it will take some time for the atmosphere to moisten up along the front. The dry air in place will likely limit the amount of rainfall we see (up to around 0.05 in or so) as the front pushes through during morning hours. We will then see the upper level wave push across this afternoon. Dew point temperatures will be increasing through this morning as the lower levels moisten up. With that said, water vapor imagery does show a pronounced dry slot moving in behind the cold front. This drier air aloft will also begin to mix down to the surface through the day. Best drying will take place along the east slopes of the northern Cascades and then out over the western basin. These areas will have a harder time holding on to enough moisture in the boundary layer to achieve the instability needed for showers in the afternoon. Thicker clouds with the front will translate east of the region in the afternoon, which will allow for some sun breaks. The northern mtns and the ID Panhandle will destabilize through the afternoon. Surface based CAPEs of 300-600 J/KG are anticipated across these areas with 0-6 km shear values of 20-30 kts. Best shear will be located across the Northeast Mtns and in the ID Panhandle. There will be the possibility for some stronger thunderstorms across these areas, but the combination of instability and shear is only marginal for stronger storms today; heavy rain, small hail and gusty outflow winds will all be possible with any stronger thunderstorms that may develop. The northern portions of the Upper Columbia Basin, Spokane Area and the Palouse will likely be on the western and southern fringe of thunderstorms today. Temperatures will be noticeably cooler and close to seasonal normals. Tonight through Wednesday: The shortwave disturbance for this afternoon will clear the region overnight with some shortwave riding building in behind. This will result in a break between weather systems that will continue into the Wednesday afternoon. There will continue to be a possibility for uncapped surface based CAPE over the higher terrain. This may lead to some isolated thunderstorm activity over the mountains; however, there will also be increasing cirrus cloud cover during the afternoon as well that will likely suppress convection late in the afternoon. /SVH Wednesday Night through Thursday Night: An active weather periods is expected, with another wave bringing rainfall chances to much of the region. A juicy air-mass will surge over the region, marked by precipitable water values over an inch. A potent disturbance will lift northeast bringing with it good chances for rainfall, and perhaps an isolated thunderstorm. Model guidance shows the best chances for the rain will be over southeast Washington and the southern Idaho Panhandle through Thursday morning, and then increase further north into the northeast WA mountains and the central/northern Idaho Panhandle during the day. Chances for precipitation were raised over these regions even further from our previous forecast, and they may not be high enough. Uncertainty does exist on the westward extent of the heavier rainfall, and this does include the Spokane areas. This forecast does not go as bullish on chances over Spokane, but this is something that will have to watched closely. Further west, given the high moisture content in the air and the presence of the upper level disturbance, it is likely that rainfall will extend into the Columbia Basin. It will likely be more scattered in nature, as opposed to locations further east. With the presence of the rainfall and widespread cloud cover, temperatures over the eastern third of Washington and the Idaho Panhandle will be cool. High there temperatures will range anywhere from 8 to 12 degrees below normal, while locations further west will see readings near normal. ty Friday through Tuesday...The upper level low in the Gulf of Alaska will continue to be the big weather player into the extended forecast period. A weak frontal system will eject off the main low on Friday. Model PWAT`s are around 160 percent of normal so plenty of moisture will be available. The best forcing will be right along the front and will be aided by orographic lift. So the focus will be for a good chance of showers across the Cascade mountains, the northeast mountains and the Idaho Panhandle mountains. Behind the front the atmosphere will destabilize enough to support a few thunderstorms that may form over the higher terrain. Through the remainder of the weekend the flow becomes zonal with a few weaker waves move along or just north of the Canadian border. We will lose the deep moisture tap. Showers and possibly some isolated thunderstorms can be expected both Saturday and Sunday during the late afternoon and early evening, but again mainly over the higher terrain. Temperatures will remain several degrees cooler than seasonal normals. Sunday night through Tuesday the low in the Gulf will begin to move east and will pump up a flat ridge of high pressure across the Pacific Northwest. A few stray afternoon showers will be possible near the cascade crest and the Panhandle mountains, otherwise the forecast will remain dry. Temperatures will begin to warm on Monday and rise to near normal by Tuesday. /Tobin && .AVIATION... 06Z TAFS: An upper level trough and an associated cold front will cross the Cascades overnight reaching Eastern Washington and North Idaho on Tuesday. Scattered showers are expected along the front and then afternoon sun breaks will destabilize the atmosphere Tuesday afternoon over northern and eastern Washington as well as the Idaho Panhandle. Isolated thunderstorms are expected with KGEG/KSFF/KCOE/KPUW/KLWS included in this threat. However with only isolated coverage expected around the TAF sites VCSH was maintained for the afternoon with no mention of TS. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 76 53 77 56 70 52 / 30 20 10 20 40 20 Coeur d`Alene 73 50 76 54 67 51 / 50 40 10 40 60 30 Pullman 75 48 76 53 67 48 / 30 10 10 50 60 20 Lewiston 83 55 84 60 73 56 / 20 10 10 60 70 20 Colville 75 48 78 53 70 50 / 70 30 10 10 40 30 Sandpoint 72 46 75 50 66 52 / 60 60 20 30 50 40 Kellogg 72 49 74 52 66 50 / 50 50 20 40 70 40 Moses Lake 85 55 84 61 81 55 / 20 0 10 10 20 10 Wenatchee 83 58 83 63 81 58 / 20 0 10 10 20 10 Omak 80 51 83 57 82 52 / 50 10 10 10 20 20 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
Area Forecast Discussion National Weather Service Spokane WA 230 AM PDT TUE JUN 24 2014 .SYNOPSIS... Following the warmest weather of the season so far...temperatures will return to normal Tuesday with the arrival of a cold front. Tuesday`s cold front will also bring a good chance of showers and thunderstorms to the Inland Northwest as well as gusty winds. The Thursday through Sunday time frame will also feature a chance of showers and thunderstorms...and will once again accompany gusty winds. && .DISCUSSION... Today: Water vapor imagery at 2:00 AM this morning shows the back side of a cold front pushing across western WA. Out ahead of the front is a decent plume of moisture with Pwats up over an inch. Forcing along the front is not particularly strong, but radar is picking up on some light shower activity across the Cascade Mtns and out over as far east as the western basin. We are pretty dry at low levels, so it will take some time for the atmosphere to moisten up along the front. The dry air in place will likely limit the amount of rainfall we see (up to around 0.05 in or so) as the front pushes through during morning hours. We will then see the upper level wave push across this afternoon. Dew point temperatures will be increasing through this morning as the lower levels moisten up. With that said, water vapor imagery does show a pronounced dry slot moving in behind the cold front. This drier air aloft will also begin to mix down to the surface through the day. Best drying will take place along the east slopes of the northern Cascades and then out over the western basin. These areas will have a harder time holding on to enough moisture in the boundary layer to achieve the instability needed for showers in the afternoon. Thicker clouds with the front will translate east of the region in the afternoon, which will allow for some sun breaks. The northern mtns and the ID Panhandle will destabilize through the afternoon. Surface based CAPEs of 300-600 J/KG are anticipated across these areas with 0-6 km shear values of 20-30 kts. Best shear will be located across the Northeast Mtns and in the ID Panhandle. There will be the possibility for some stronger thunderstorms across these areas, but the combination of instability and shear is only marginal for stronger storms today; heavy rain, small hail and gusty outflow winds will all be possible with any stronger thunderstorms that may develop. The northern portions of the Upper Columbia Basin, Spokane Area and the Palouse will likely be on the western and southern fringe of thunderstorms today. Temperatures will be noticeably cooler and close to seasonal normals. Tonight through Wednesday: The shortwave disturbance for this afternoon will clear the region overnight with some shortwave riding building in behind. This will result in a break between weather systems that will continue into the Wednesday afternoon. There will continue to be a possibility for uncapped surface based CAPE over the higher terrain. This may lead to some isolated thunderstorm activity over the mountains; however, there will also be increasing cirrus cloud cover during the afternoon as well that will likely suppress convection late in the afternoon. /SVH Wednesday Night through Thursday Night: An active weather periods is expected, with another wave bringing rainfall chances to much of the region. A juicy air-mass will surge over the region, marked by precipitable water values over an inch. A potent disturbance will lift northeast bringing with it good chances for rainfall, and perhaps an isolated thunderstorm. Model guidance shows the best chances for the rain will be over southeast Washington and the southern Idaho Panhandle through Thursday morning, and then increase further north into the northeast WA mountains and the central/northern Idaho Panhandle during the day. Chances for precipitation were raised over these regions even further from our previous forecast, and they may not be high enough. Uncertainty does exist on the westward extent of the heavier rainfall, and this does include the Spokane areas. This forecast does not go as bullish on chances over Spokane, but this is something that will have to watched closely. Further west, given the high moisture content in the air and the presence of the upper level disturbance, it is likely that rainfall will extend into the Columbia Basin. It will likely be more scattered in nature, as opposed to locations further east. With the presence of the rainfall and widespread cloud cover, temperatures over the eastern third of Washington and the Idaho Panhandle will be cool. High there temperatures will range anywhere from 8 to 12 degrees below normal, while locations further west will see readings near normal. ty Friday through Tuesday...The upper level low in the Gulf of Alaska will continue to be the big weather player into the extended forecast period. A weak frontal system will eject off the main low on Friday. Model PWAT`s are around 160 percent of normal so plenty of moisture will be available. The best forcing will be right along the front and will be aided by orographic lift. So the focus will be for a good chance of showers across the Cascade mountains, the northeast mountains and the Idaho Panhandle mountains. Behind the front the atmosphere will destabilize enough to support a few thunderstorms that may form over the higher terrain. Through the remainder of the weekend the flow becomes zonal with a few weaker waves move along or just north of the Canadian border. We will lose the deep moisture tap. Showers and possibly some isolated thunderstorms can be expected both Saturday and Sunday during the late afternoon and early evening, but again mainly over the higher terrain. Temperatures will remain several degrees cooler than seasonal normals. Sunday night through Tuesday the low in the Gulf will begin to move east and will pump up a flat ridge of high pressure across the Pacific Northwest. A few stray afternoon showers will be possible near the cascade crest and the Panhandle mountains, otherwise the forecast will remain dry. Temperatures will begin to warm on Monday and rise to near normal by Tuesday. /Tobin && .AVIATION... 06Z TAFS: An upper level trough and an associated cold front will cross the Cascades overnight reaching Eastern Washington and North Idaho on Tuesday. Scattered showers are expected along the front and then afternoon sun breaks will destabilize the atmosphere Tuesday afternoon over northern and eastern Washington as well as the Idaho Panhandle. Isolated thunderstorms are expected with KGEG/KSFF/KCOE/KPUW/KLWS included in this threat. However with only isolated coverage expected around the TAF sites VCSH was maintained for the afternoon with no mention of TS. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 76 53 77 56 70 52 / 30 20 10 20 40 20 Coeur d`Alene 73 50 76 54 67 51 / 50 40 10 40 60 30 Pullman 75 48 76 53 67 48 / 30 10 10 50 60 20 Lewiston 83 55 84 60 73 56 / 20 10 10 60 70 20 Colville 75 48 78 53 70 50 / 70 30 10 10 40 30 Sandpoint 72 46 75 50 66 52 / 60 60 20 30 50 40 Kellogg 72 49 74 52 66 50 / 50 50 20 40 70 40 Moses Lake 85 55 84 61 81 55 / 20 0 10 10 20 10 Wenatchee 83 58 83 63 81 58 / 20 0 10 10 20 10 Omak 80 51 83 57 82 52 / 50 10 10 10 20 20 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
Area Forecast Discussion National Weather Service Spokane WA 230 AM PDT TUE JUN 24 2014 .SYNOPSIS... Following the warmest weather of the season so far...temperatures will return to normal Tuesday with the arrival of a cold front. Tuesday`s cold front will also bring a good chance of showers and thunderstorms to the Inland Northwest as well as gusty winds. The Thursday through Sunday time frame will also feature a chance of showers and thunderstorms...and will once again accompany gusty winds. && .DISCUSSION... Today: Water vapor imagery at 2:00 AM this morning shows the back side of a cold front pushing across western WA. Out ahead of the front is a decent plume of moisture with Pwats up over an inch. Forcing along the front is not particularly strong, but radar is picking up on some light shower activity across the Cascade Mtns and out over as far east as the western basin. We are pretty dry at low levels, so it will take some time for the atmosphere to moisten up along the front. The dry air in place will likely limit the amount of rainfall we see (up to around 0.05 in or so) as the front pushes through during morning hours. We will then see the upper level wave push across this afternoon. Dew point temperatures will be increasing through this morning as the lower levels moisten up. With that said, water vapor imagery does show a pronounced dry slot moving in behind the cold front. This drier air aloft will also begin to mix down to the surface through the day. Best drying will take place along the east slopes of the northern Cascades and then out over the western basin. These areas will have a harder time holding on to enough moisture in the boundary layer to achieve the instability needed for showers in the afternoon. Thicker clouds with the front will translate east of the region in the afternoon, which will allow for some sun breaks. The northern mtns and the ID Panhandle will destabilize through the afternoon. Surface based CAPEs of 300-600 J/KG are anticipated across these areas with 0-6 km shear values of 20-30 kts. Best shear will be located across the Northeast Mtns and in the ID Panhandle. There will be the possibility for some stronger thunderstorms across these areas, but the combination of instability and shear is only marginal for stronger storms today; heavy rain, small hail and gusty outflow winds will all be possible with any stronger thunderstorms that may develop. The northern portions of the Upper Columbia Basin, Spokane Area and the Palouse will likely be on the western and southern fringe of thunderstorms today. Temperatures will be noticeably cooler and close to seasonal normals. Tonight through Wednesday: The shortwave disturbance for this afternoon will clear the region overnight with some shortwave riding building in behind. This will result in a break between weather systems that will continue into the Wednesday afternoon. There will continue to be a possibility for uncapped surface based CAPE over the higher terrain. This may lead to some isolated thunderstorm activity over the mountains; however, there will also be increasing cirrus cloud cover during the afternoon as well that will likely suppress convection late in the afternoon. /SVH Wednesday Night through Thursday Night: An active weather periods is expected, with another wave bringing rainfall chances to much of the region. A juicy air-mass will surge over the region, marked by precipitable water values over an inch. A potent disturbance will lift northeast bringing with it good chances for rainfall, and perhaps an isolated thunderstorm. Model guidance shows the best chances for the rain will be over southeast Washington and the southern Idaho Panhandle through Thursday morning, and then increase further north into the northeast WA mountains and the central/northern Idaho Panhandle during the day. Chances for precipitation were raised over these regions even further from our previous forecast, and they may not be high enough. Uncertainty does exist on the westward extent of the heavier rainfall, and this does include the Spokane areas. This forecast does not go as bullish on chances over Spokane, but this is something that will have to watched closely. Further west, given the high moisture content in the air and the presence of the upper level disturbance, it is likely that rainfall will extend into the Columbia Basin. It will likely be more scattered in nature, as opposed to locations further east. With the presence of the rainfall and widespread cloud cover, temperatures over the eastern third of Washington and the Idaho Panhandle will be cool. High there temperatures will range anywhere from 8 to 12 degrees below normal, while locations further west will see readings near normal. ty Friday through Tuesday...The upper level low in the Gulf of Alaska will continue to be the big weather player into the extended forecast period. A weak frontal system will eject off the main low on Friday. Model PWAT`s are around 160 percent of normal so plenty of moisture will be available. The best forcing will be right along the front and will be aided by orographic lift. So the focus will be for a good chance of showers across the Cascade mountains, the northeast mountains and the Idaho Panhandle mountains. Behind the front the atmosphere will destabilize enough to support a few thunderstorms that may form over the higher terrain. Through the remainder of the weekend the flow becomes zonal with a few weaker waves move along or just north of the Canadian border. We will lose the deep moisture tap. Showers and possibly some isolated thunderstorms can be expected both Saturday and Sunday during the late afternoon and early evening, but again mainly over the higher terrain. Temperatures will remain several degrees cooler than seasonal normals. Sunday night through Tuesday the low in the Gulf will begin to move east and will pump up a flat ridge of high pressure across the Pacific Northwest. A few stray afternoon showers will be possible near the cascade crest and the Panhandle mountains, otherwise the forecast will remain dry. Temperatures will begin to warm on Monday and rise to near normal by Tuesday. /Tobin && .AVIATION... 06Z TAFS: An upper level trough and an associated cold front will cross the Cascades overnight reaching Eastern Washington and North Idaho on Tuesday. Scattered showers are expected along the front and then afternoon sun breaks will destabilize the atmosphere Tuesday afternoon over northern and eastern Washington as well as the Idaho Panhandle. Isolated thunderstorms are expected with KGEG/KSFF/KCOE/KPUW/KLWS included in this threat. However with only isolated coverage expected around the TAF sites VCSH was maintained for the afternoon with no mention of TS. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 76 53 77 56 70 52 / 30 20 10 20 40 20 Coeur d`Alene 73 50 76 54 67 51 / 50 40 10 40 60 30 Pullman 75 48 76 53 67 48 / 30 10 10 50 60 20 Lewiston 83 55 84 60 73 56 / 20 10 10 60 70 20 Colville 75 48 78 53 70 50 / 70 30 10 10 40 30 Sandpoint 72 46 75 50 66 52 / 60 60 20 30 50 40 Kellogg 72 49 74 52 66 50 / 50 50 20 40 70 40 Moses Lake 85 55 84 61 81 55 / 20 0 10 10 20 10 Wenatchee 83 58 83 63 81 58 / 20 0 10 10 20 10 Omak 80 51 83 57 82 52 / 50 10 10 10 20 20 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
Area Forecast Discussion National Weather Service Spokane WA 230 AM PDT TUE JUN 24 2014 .SYNOPSIS... Following the warmest weather of the season so far...temperatures will return to normal Tuesday with the arrival of a cold front. Tuesday`s cold front will also bring a good chance of showers and thunderstorms to the Inland Northwest as well as gusty winds. The Thursday through Sunday time frame will also feature a chance of showers and thunderstorms...and will once again accompany gusty winds. && .DISCUSSION... Today: Water vapor imagery at 2:00 AM this morning shows the back side of a cold front pushing across western WA. Out ahead of the front is a decent plume of moisture with Pwats up over an inch. Forcing along the front is not particularly strong, but radar is picking up on some light shower activity across the Cascade Mtns and out over as far east as the western basin. We are pretty dry at low levels, so it will take some time for the atmosphere to moisten up along the front. The dry air in place will likely limit the amount of rainfall we see (up to around 0.05 in or so) as the front pushes through during morning hours. We will then see the upper level wave push across this afternoon. Dew point temperatures will be increasing through this morning as the lower levels moisten up. With that said, water vapor imagery does show a pronounced dry slot moving in behind the cold front. This drier air aloft will also begin to mix down to the surface through the day. Best drying will take place along the east slopes of the northern Cascades and then out over the western basin. These areas will have a harder time holding on to enough moisture in the boundary layer to achieve the instability needed for showers in the afternoon. Thicker clouds with the front will translate east of the region in the afternoon, which will allow for some sun breaks. The northern mtns and the ID Panhandle will destabilize through the afternoon. Surface based CAPEs of 300-600 J/KG are anticipated across these areas with 0-6 km shear values of 20-30 kts. Best shear will be located across the Northeast Mtns and in the ID Panhandle. There will be the possibility for some stronger thunderstorms across these areas, but the combination of instability and shear is only marginal for stronger storms today; heavy rain, small hail and gusty outflow winds will all be possible with any stronger thunderstorms that may develop. The northern portions of the Upper Columbia Basin, Spokane Area and the Palouse will likely be on the western and southern fringe of thunderstorms today. Temperatures will be noticeably cooler and close to seasonal normals. Tonight through Wednesday: The shortwave disturbance for this afternoon will clear the region overnight with some shortwave riding building in behind. This will result in a break between weather systems that will continue into the Wednesday afternoon. There will continue to be a possibility for uncapped surface based CAPE over the higher terrain. This may lead to some isolated thunderstorm activity over the mountains; however, there will also be increasing cirrus cloud cover during the afternoon as well that will likely suppress convection late in the afternoon. /SVH Wednesday Night through Thursday Night: An active weather periods is expected, with another wave bringing rainfall chances to much of the region. A juicy air-mass will surge over the region, marked by precipitable water values over an inch. A potent disturbance will lift northeast bringing with it good chances for rainfall, and perhaps an isolated thunderstorm. Model guidance shows the best chances for the rain will be over southeast Washington and the southern Idaho Panhandle through Thursday morning, and then increase further north into the northeast WA mountains and the central/northern Idaho Panhandle during the day. Chances for precipitation were raised over these regions even further from our previous forecast, and they may not be high enough. Uncertainty does exist on the westward extent of the heavier rainfall, and this does include the Spokane areas. This forecast does not go as bullish on chances over Spokane, but this is something that will have to watched closely. Further west, given the high moisture content in the air and the presence of the upper level disturbance, it is likely that rainfall will extend into the Columbia Basin. It will likely be more scattered in nature, as opposed to locations further east. With the presence of the rainfall and widespread cloud cover, temperatures over the eastern third of Washington and the Idaho Panhandle will be cool. High there temperatures will range anywhere from 8 to 12 degrees below normal, while locations further west will see readings near normal. ty Friday through Tuesday...The upper level low in the Gulf of Alaska will continue to be the big weather player into the extended forecast period. A weak frontal system will eject off the main low on Friday. Model PWAT`s are around 160 percent of normal so plenty of moisture will be available. The best forcing will be right along the front and will be aided by orographic lift. So the focus will be for a good chance of showers across the Cascade mountains, the northeast mountains and the Idaho Panhandle mountains. Behind the front the atmosphere will destabilize enough to support a few thunderstorms that may form over the higher terrain. Through the remainder of the weekend the flow becomes zonal with a few weaker waves move along or just north of the Canadian border. We will lose the deep moisture tap. Showers and possibly some isolated thunderstorms can be expected both Saturday and Sunday during the late afternoon and early evening, but again mainly over the higher terrain. Temperatures will remain several degrees cooler than seasonal normals. Sunday night through Tuesday the low in the Gulf will begin to move east and will pump up a flat ridge of high pressure across the Pacific Northwest. A few stray afternoon showers will be possible near the cascade crest and the Panhandle mountains, otherwise the forecast will remain dry. Temperatures will begin to warm on Monday and rise to near normal by Tuesday. /Tobin && .AVIATION... 06Z TAFS: An upper level trough and an associated cold front will cross the Cascades overnight reaching Eastern Washington and North Idaho on Tuesday. Scattered showers are expected along the front and then afternoon sun breaks will destabilize the atmosphere Tuesday afternoon over northern and eastern Washington as well as the Idaho Panhandle. Isolated thunderstorms are expected with KGEG/KSFF/KCOE/KPUW/KLWS included in this threat. However with only isolated coverage expected around the TAF sites VCSH was maintained for the afternoon with no mention of TS. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 76 53 77 56 70 52 / 30 20 10 20 40 20 Coeur d`Alene 73 50 76 54 67 51 / 50 40 10 40 60 30 Pullman 75 48 76 53 67 48 / 30 10 10 50 60 20 Lewiston 83 55 84 60 73 56 / 20 10 10 60 70 20 Colville 75 48 78 53 70 50 / 70 30 10 10 40 30 Sandpoint 72 46 75 50 66 52 / 60 60 20 30 50 40 Kellogg 72 49 74 52 66 50 / 50 50 20 40 70 40 Moses Lake 85 55 84 61 81 55 / 20 0 10 10 20 10 Wenatchee 83 58 83 63 81 58 / 20 0 10 10 20 10 Omak 80 51 83 57 82 52 / 50 10 10 10 20 20 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
Area Forecast Discussion National Weather Service Spokane WA 1026 PM PDT MON JUN 23 2014 .SYNOPSIS... Following the warmest weather of the season so far...temperatures will return to normal Tuesday with the arrival of a cold front. Tuesday`s cold front will also bring a good chance of showers and thunderstorms to the Inland Northwest as well as gusty winds. The Thursday through Sunday time frame will also feature a chance of showers and thunderstorms...and will once again accompany gusty winds. && .DISCUSSION... Update: Water vapor satellite from this evening showed an upper level wave moving into Western Washington and Oregon. Radar imagery shows a narrow area of rain associated with a mid level front. As this front crosses the Cascades overnight...it will be moving into an area of dry lower levels. However sufficient mid level moisture and lift should be enough to bring scattered showers to the East Slopes (numerous showers near the Cascade crest), with isolated showers into the Okanogan Valley, Wenatchee area, and western Columbia basin. Some minor POP increases have been made based on radar trends and the latest 00z HRRR showing the eastern edge of the showers tonight making it into Moses Lake. For Eastern Washington and North Idaho the chance of showers will hold off til Tuesday morning when the mid level front swings through. The warm day today followed by increased cloud cover tonight will yield a mild night for the Inland Northwest with valley lows mainly in the mid 50s to lower 60s. JW && .AVIATION... 06Z TAFS: An upper level trough and an associated cold front will cross the Cascades overnight reaching Eastern Washington and North Idaho on Tuesday. Scattered showers are expected along the front and then afternoon sun breaks will destabilize the atmosphere Tuesday afternoon over northern and eastern Washington as well as the Idaho Panhandle. Isolated thunderstorms are expected with KGEG/KSFF/KCOE/KPUW/KLWS included in this threat. However with only isolated coverage expected around the TAF sites VCSH was maintained for the afternoon with no mention of TS. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 60 74 53 77 56 72 / 0 30 10 10 30 40 Coeur d`Alene 56 73 50 76 53 70 / 0 40 20 10 40 50 Pullman 54 73 48 76 53 71 / 0 30 10 10 60 60 Lewiston 61 80 55 84 60 75 / 0 20 10 10 60 60 Colville 53 75 48 78 53 74 / 10 60 20 10 10 40 Sandpoint 51 73 46 75 49 68 / 10 60 30 20 40 50 Kellogg 53 74 49 74 51 69 / 10 40 30 20 40 60 Moses Lake 63 85 55 84 61 83 / 20 20 0 10 10 20 Wenatchee 67 83 58 83 63 82 / 20 20 0 10 10 20 Omak 61 81 51 83 58 83 / 20 50 10 10 10 20 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1046 PM MDT MON JUN 23 2014 .SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY) ISSUED AT 245 PM MDT MON JUN 23 2014 DEEPER CUMULUS HAVE STARTED TO DEVELOP OVER THE PAST HOUR IN THE CONVERGENCE ALONG THE SOUTHERN LARAMIE RANGE...BUT SO FAR NOT A WHOLE LOT OF UPSCALE GROWTH AS THESE CELLS HAVE MOVED INTO THE PLAINS. DEW POINTS ARE CURRENTLY IN THE UPPER 40S TO MID 50S TO THE EAST OF THE LARAMIE RANGE. THE MODELS CONTINUE TO INDICATE AN ENVIRONMENT CONDUCIVE FOR SOME STRONG TO SEVERE STORMS IN AREAS NEAR THE COLORADO BORDER THROUGH THIS EVENING. SPC MESOANALYSIS SHOWS MLCAPES OF 1000-1250 J/KG STRETCHING ALONG INTERSTATE 80 OVER THE PLAINS COMBINED WITH 35-40 KT OF BULK SHEAR. THE HRRR MODEL HAS A LONE STORM MOVING EASTWARD ALONG THE COLORADO BORDER THROUGH THE LATE AFTN. SO VERY SIMILAR TO YESTERDAY...WE CONTINUE TO EXPECT A MARGINAL SEVERE THREAT OVER LARAMIE COUNTY AND EXTENDING EASTWARD INTO THE SOUTHERN PANHANDLE. KEPT A SLIGHT CHANCE OF TSTMS GOING THROUGH THE NIGHT WITH A WEAK SHORTWAVE MOVING OVERHEAD...WHICH IS CURRENTLY ACROSS SOUTHWESTERN WY. THE REMAINDER OF THE SHORT TERM WILL FEATURE GRADUALLY INCREASING TEMPS AND INSTABILITY. FLOW ALOFT IS STILL WEST TO NORTHWESTERLY ON TUES WITH THE MID LEVEL RIDGE AXIS TO THE WEST OF THE CWA. DEW POINTS INCH UP SLIGHTLY...SO CAPE VALUES WILL INCREASE OVER TODAY WITH THE GFS SHOWING AROUND 1500 J/KG ALONG INTERSTATE 80. INSTABILITY DROPS OFF TO 750 J/KG ACROSS CONVERSE/NIOBRARA COUNTIES AND INTO THE NORTHERN NEBRASKA PANHANDLE. BEST CHANCE OF SEVERE STORMS WILL LIKELY BE OVER AREAS TO THE SOUTH OF A WHEATLAND TO SCOTTSBLUFF LINE. TEMPS ON TUES WILL BE A COUPLE DEGREES WARMER THAN THIS AFTN. THE BEST POTENTIAL FOR MORE WIDESPREAD SEVERE STORMS IS STILL LOOKING LIKE WED. A SFC LOW DEVELOPS OVER NORTH-CENTRAL WY DURING THE AFTN AND WITH PERSISTENT SOUTHEAST WINDS...ADDITIONAL MOISTURE ADVECTION HAS OCCURRED OVER THE PLAINS. DEW POINTS BY WED AFTN ARE INTO THE UPPER 50S AND LOW 60S ALMOST EVERYWHERE TO THE EAST OF THE LARAMIE RANGE WITH CAPE VALUES OF 1500-2000. ALTHOUGH FLOW ALOFT WILL BE WEAKER THAN THE PRECEDING DAYS DUE TO THE PROXIMITY OF THE RIDGE AXIS...THERE IS STILL AROUND 40 KT OF DEEP LAYER SHEAR. ITS A BIT EARLY TO PINPOINT THE AREA OVER THE PLAINS THAN HAS THE BEST POTENTIAL FOR SEVERE STORMS...BUT IT WOULD SEEM TO BE OVER THE NORTHERN HALF...WHICH IS CLOSEST TO A WEAK SHORTWAVE THAN MOVES INTO WESTERN SOUTH DAKOTA DURING THE EVENING. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 225 PM MDT MON JUN 23 2014 MINOR MODEL DIFFERENCES NOTED IN THE MEDIUM RANGE PERIOD. WEAK UPPER RIDGE OVER THE PLAINS YIELDS TO A BROADER UPPER TROUGH BY THE WEEKEND. THE SOUTHWESTERLY FLOW ALOFT VEERS TO WESTERLY. SURFACE PATTERN WILL BE FAIRLY WEAK WITH A RIDGE WEST OF THE MOUNTAINS AND TROUGH ACROSS THE PLAINS. LOW LEVEL CONVERGENCE AND MOISTURE COMBINED WITH PASSING WEAK DISTURBANCES WILL KEEP WIDELY SCATTERED SHOWERS AND TSTORMS IN THE FORECAST THURSDAY THROUGH SATURDAY. SEVERE THREAT WILL BE MINIMAL GIVEN WEAK SHEAR...BUT CANNOT RULE OUT ISOLATED STRONG CONVECTION FOR THE PLAINS. UPPER TROUGH LIFTS NORTHEAST THROUGH THE NORTHERN GREAT PLAINS AND UPPER MIDWEST SUNDAY AND MONDAY WITH DRIER WEST-NORTHWEST FLOW PATTERN. TEMPERATURES WILL AVERAGE ABOVE SEASONAL NORMALS WITH HIGHS IN THE 80S FOR LOWER ELEVATIONS WITH 60S AND 70S FOR THE HIGH COUNTRY. LOWS WILL BE IN THE 40S AND 50S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY EVENING) ISSUED AT 1040 PM MDT MON JUN 23 2014 CONVECTION CONTINUES TO DECREASE IN COVERAGE AND STRENGTH THIS EVENING...WITH THE BULK OF THE STRONGEST ACTIVITY SHIFTING SOUTH INTO COLORADO. THERE CONTINUES TO BE SOME SHOWERS AND WEAK THUNDERSTORMS ACROSS PORTIONS OF CENTRAL AND SOUTHEAST WYOMING. THIS ACTIVITY WILL CONTINUE TO DRIFT SOUTHEAST THROUGH AREA TERMINALS LATER TONIGHT AS AN UPPER-LEVEL DISTURBANCE MOVES THRU. DIFFICULT TO KNOW JUST HOW WIDESPREAD THIS WILL BE...ESPECIALLY GIVEN IT IS OCCURRING AT NIGHT. FOR NOW HAVE TRENDED THE 06Z TAFS WITH VCSH IN MANY AREAS TO ACCOUNT FOR THIS POSSIBILITIES. ADDITIONALLY...HAVE SIDED WITH PERSISTENCE IN AREA OF FOG/LOW STRATUS DEVELOPMENT TONIGHT AS THE PATTERN HAS CHANGED LITTLE FROM LAST NIGHT. SO BROUGHT FOG INTO KLAR...KCDR AND A LOWER STRATUS DECK INTO KCYS 08-14Z. STILL LOOKS LIKE ANOTHER DAY OF AFTERNOON AND EVENING THUNDERSTORM DEVELOPMENT FOR TUESDAY. THE BEST COVERAGE AGAIN LOOKS TO BE AT KLAR AND KCYS. THIS ACTIVITY MAY AGAIN SHIFT INTO THE WESTERN NEBRASKA SITES AFTER 00Z. && .FIRE WEATHER... ISSUED AT 245 PM MDT MON JUN 23 2014 MINIMAL FIRE WEATHER CONCERNS THROUGH MIDWEEK. SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE EACH AFTERNOON AND EVENING THROUGH THURSDAY. THE COVERAGE WILL BE HIGHEST AND THE BEST CHANCE OF WETTING RAINS WILL EXIST TO THE EAST OF THE LARAMIE RANGE. TEMPERATURES WILL BEGIN TO INCREASE ON WEDNESDAY AND THURSDAY SUCH THAT MINIMUM AFTERNOON HUMIDITY VALUES WILL DROP TO AROUND 15 PERCENT WEST OF THE LARAMIE RANGE. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...FINCH LONG TERM...JAMSKI AVIATION...HAHN FIRE WEATHER...FINCH
AREA FORECAST DISCUSSION
NWS ALBANY NY
639 AM EDT TUE JUN 24 2014 .SYNOPSIS... HIGH PRESSURE OFFSHORE WILL BRING SOUTHERLY WINDS WILL SLOWLY INCREASE OUR HUMIDITY. A COLD FRONT OVER THE OHIO VALLEY WILL BEGIN TO VERY SLOWLY APPROACH OUR REGION BY TONIGHT. THIS FRONT COULD TRIGGER SHOWERS AND THUNDERSTORMS MAINLY TO THE WEST OF THE CAPITAL REGION LATER TODAY. TONIGHT THROUGH EARLY THURSDAY...THE FRONT WILL SLOWLY DRAG THROUGH THE REGION...WITH WAVES OF LOW PRESSURE FORMING ALONG IT...WHICH WILL PRODUCE BOUTS OF SHOWERS AND POSSIBLE THUNDERSTORMS. ANY THUNDERSTORM COULD CONTAIN GUSTY WINDS AND HEAVY RAINFALL...ESPECIALLY WEDNESDAY AFTERNOON AND EVENING. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 630 AM EDT...SCATTERED TO NUMEROUS SHOWERS WERE WORKING ACROSS MUCH OF HERKIMER COUNTY. STILL...NO CLOUD TO GROUND LIGHTNING AND THE LATEST RUC AND MSAS ANALYSIS INDICATED LITTLE OR NO INSTABILITY. SO WE WILL CALL THESE SCATTERED THROUGH MID MORNING. THE SHOWERS LOOK TO EXIT AND THERE MIGHT BE A LULL BEFORE MORE SHOWERS AND STORMS FORM LATER TODAY. THE VAST MAJORITY OF THE REGION REMAINED DRY AND MILD AS A PERSISTENT SOUTHERLY BREEZE HAS KEPT TEMPERATURES MAINLY IN THE 60S AT THIS HOUR...WITH ONLY A FEW UPPER 50S IN THE SHELTERED MOUNTAIN VALLEYS. SO FOR THIS UPDATE...CHANGED SOME OF THE POP/WEATHER GRIDS BASED ON THE CURRENT RADAR TRENDS AND OF COURSE TWEAKED THE HOURLY GRIDS. TODAY...SUNSHINE WILL BE MIXED WITH A GOOD DEAL OF HIGH CLOUDS...IN THE CAPITAL REGION...LESS SO FURTHER SOUTH AND EAST. IT WILL BE MOSTLY TO TOTALLY CLOUDY FURTHER NORTH AND WEST. A SOUTH WIND WILL AVERAGE 10 TO 15 MPH...WITH GUSTS UP TO 25 TO PERHAPS EVEN 30 MPH AT TIMES. TEMPERATURES WILL ONCE AGAIN CLIMB WELL INTO THE 80S FROM THE CAPITAL REGION SOUTH AND EAST...WITH SOME LOCALITIES POSSIBLY REACHING THE UPPER 80S. FURTHER NORTH AND WEST...WITH THICKER CLOUDS...TEMPERATURES WILL NOT BE QUITE AS WARM...CLOSER TO 80. DEWPOINTS WILL SLOWLY CREEP THROUGH THE 50S...REACHING 60 OR HIGHER FROM THE CAPITAL REGION AND AREAS NORTH AND WEST. INSTABILITY WILL INCREASE AND THERE WILL LIKELY BE OLD OUTFLOW BOUNDARIES ACROSS THE MOHAWK VALLEY AND SOUTHERN ADIRONDACKS. ALL OF THE FACTORS WILL INCREASE THE CHANCE OF SHOWER AND THUNDERSTORM ACTIVITY. THE 0-6KM BULK SHEAR WILL INCREASE TO ABOUT 30KTS FROM THE SOUTHWEST. THUNDERSTORM THAT DO DEVELOP COULD END UP PRODUCING SOME GUSTY WINDS (PROBABLY SUBSEVERE) BUT A ROGUE SEVERE THUNDERSTORM IS POSSIBLE WITH A BOWING SEGMENT. PWATS RAMP TO NEARLY 2 INCHES...SO ANY THUNDERSTORM COULD HEAVY RAINFALL. WE CONTINUE TO USE ENHANCED WORDING IN OUR GRIDS NORTH AND WEST OF THE CAPITAL REGION. FROM ALBANY SOUTH AND EAST...WE ONLY GAVE SLIGHT POPS (ACTUALLY NONE SOUTHEAST OF ALBANY AS RIDGING ALOFT WILL LIKELY PREVENT ANY UPWARD MOTION AND RESULTANT SHOWERS AND STORMS. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... SINCE THE COLD FRONT WILL STILL BE OUR WEST TONIGHT...THUNDERSTORM ACTIVITY THAT DOES DEVELOP LATE IN THE DAY...MIGHT ACTUALLY DIMINISH OVERNIGHT..ALTHOUGH REMNANTS OF THOSE STORMS COULD CERTAINLY MOVE FURTHER EAST. DEWPOINTS WILL CLIMB INTO THE 60S EVERYWHERE MAKING IT A MUGGY NIGHT. LOWS WILL BE GENERALLY IN THE 60S...CLOSER TO 70 IN THE IMMEDIATE CAPITAL REGION. WEDNESDAY AND WEDNESDAY NIGHT...MORE ORGANIZED UPPER DYNAMICS...A LITTLE BOUNDARY LAYER WIND CORE...MUCH DEEPER MOISTURE AND SOME UPPER DIVERGENCE IS EXPECTED TO CONTRIBUTE TO AN ORGANIZED BAND OF THUNDERSTORMS AHEAD AND ALONG A COLD FRONT. INSTABILITY WILL LARGELY BE BASED AT THE SURFACE AS MIDLEVEL LAPSE RATES STILL DO NOT LOOK IMPRESSIVE. STILL ENOUGH INSTABILITY SO WE WILL HAVE TO WATCH FOR ISOLATED SEVERE WIND GUSTS...BUT MAYBE MORE OF A VERY HEAVY RAIN POTENTIAL BASED ON THE VERY ANOMALOUSLY HIGH PWAT VALUES AROUND TWO INCHES REGION WIDE. GUIDANCE WAS IN SLIGHTLY BETTER AGREEMENT WHERE THE AXIS OF HEAVIES RAINFALL WILL TAKE PLACE. THE REALLY MOST OF THE AREA LOOKS TO POTENTIALLY RECEIVE AN INCH OR BETTER OF RAINFALL. INITIALLY...NORTHERN AREAS WILL GET HIT EARLY WEDNESDAY...WITH THE AXIS SLOWLY SHIFTING SOUTH AND EAST LATE WEDNESDAY INTO EARLY THURSDAY. WE ARE STILL NOT READY TO ISSUE ANY FLASH FLOOD WATCHES YET...AS THE BULK OF THE RAIN WILL NOT FALL UNTIL LATER WEDNESDAY AND THE CONFIDENCE OF FLASH FLOODING IS BELOW 50 PERCENT DUE TO SOMEWHAT DRY CONDITIONS GOING INTO THIS EVENT. MORE ABOUT HYDROLOGICAL ISSUES CAN BE FOUND IN OUR HYDROLOGICAL SECTION. THERE ARE STILL INDICATIONS OF LINGERING UPPER ENERGY AND A LOW LEVEL FEATURE FOR ONE LAST ROUND OF LOW LEVEL FORCING AS THE COLD FRONT CONTINUES ITS PROGRESS EAST AND SOUTH. SO...LINGERING ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS THURSDAY MORNING IN MOST PLACES...BUT THROUGHOUT THE DAY IN THE MID HUDSON VALLEY AND NW CT. TEMPERATURES ON WEDNESDAY WILL HIGHLY DEPEND ON HOW CLOUDS IT REMAINS. THE 00Z NAM MOS NUMBERS WERE COOLER BASED ON MORE CLOUDS WHILE THE MAV MOS NUMBERS INDICATED PERHAPS A LITTLE MORE SUNSHINE. FOR NOW...WENT WITH THE MAV/MET MIX BUT LEANING TOWARD THE COOLER MET NUMBERS. THIS WOULD GIVE HIGHS CLOSE TO 80 AROUND THE CAPITAL REGION...LOWER TO MID 80S FURTHER SOUTH...70S WELL NORTH AND WEST. DEWPOINTS WILL BE HIGH HOLDING WELL INTO THE 60S. WEDNESDAY NIGHT LOWS WILL RANGE FROM THE UPPER 50S TO MID 60S. HIGHS THURSDAY WITH CLOUDS GIVING TO A FEW LATE TIME SUNNY BREAKS AND ONLY WEAK COLD AIR ADVECTION WILL RANGE FROM THE MID 70S NORTHWEST TO LOWER 80S SOUTH OF ALBANY. && .LONG TERM /FRIDAY THROUGH MONDAY/... BEHIND THE COLD FRONT THAT EXITS THE REGION THURSDAY NIGHT...EXPECT THE ENTIRE REGION TO ENJOY SOME TRANQUIL AND DRY WEATHER FRIDAY THROUGH SUNDAY NIGHT WITH MAINLY CLEAR TO PARTLY CLOUDY SKIES. AN INCREASINGLY MOIST SOUTHWEST FLOW OF AIR COULD BRING SOME SHOWERS AND TSTMS TO THE REGION ON MONDAY. TEMPERATURES WILL BE NEAR TO SLIGHT ABOVE NORMAL FRIDAY THROUGH MONDAY. HIGHS FRIDAY AND SATURDAY WILL BE IN THE 70S TO AROUND 80. LOWS FRIDAY AND SATURDAY NIGHTS IN THE 50S TO AROUND 60. GETTING WARMER ON SUNDAY WITH HIGHS IN THE MID 70S TO LOWER 80S. LOWS SUNDAY NIGHT IN THE MID 50S TO LOWER 60S. HIGHS MONDAY IN THE UPPER 70S TO MID 80S. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... A FRONTAL BOUNDARY WILL SLOWLY MOVE EAST FROM THE GREAT LAKES REGION ON TODAY AND TONIGHT. THERE WILL BE A SOUTHERLY FLOW AHEAD OF THIS SYSTEM...BUT AT THIS POINT FORECAST MODELS INDICATE THAT MOST OF THE SHOWERS/TSTMS ASSOCIATED WITH THIS FRONTAL BOUNDARY WILL REMAIN TO THE NORTH AND WEST OF THE TAF SITES THROUGH MOST OF THE THE TAF PERIOD ENDING AT 12Z WEDNESDAY. AT KALB HAVE INDICATED VCSH IN THE FORECAST AFTER 23Z TUESDAY...AND AFTER 21Z AT KGFL. THERE IS ALSO A TEMPO GROUP FOR MVFR SHOWERS TO START THE TAF PERIOD AT KGFL DUE TO RADAR SHOWING A BATCH OF SHOWERS MOVING EAST ACROSS THE ADIRONDACKS AS OF 630 AM. AT KPOU/KPSF...HAVE NOT FORECAST ANY PCPN THROUGH 12 WEDNESDAY. MAINLY VFR CONDITIONS HAVE BEEN FORECAST AT THE TAF SITES THROUGH 12Z WEDNESDAY. THE EXCEPTIONS ARE THE PERIOD OF PSSIBLE MVFR AT KGFL TO START THE TAF PERIOD. IN ADDITION...MODELS AND STATISTICAL GUIDANCE ARE INDICATING LOWERING CIGS LATE TONIGHT AS THE SOUTHERLY FLOW OFF THE ATLANTIC PERSISTS AND BRINGS LOW-LEVEL MOISTURE NORTHWARD. AFTER AROUND 07Z TONIGHT HAVE FORECAST MVFR CIGS AT ALL THE TAF SITES. SOUTHERLY WINDS WILL INCREASE AT ALL THE TAF SITES ON TODAY TO 10 TO 15 KTS WITH GUSTS OF 16 TO 22 KTS. WIND SPEEDS WILL DECREASE TO 5 TO 10 KTS TUESDAY NIGHT...WITH SOME GUSTS OVER 15 KTS AT KALB. OUTLOOK... WEDNESDAY: HIGH OPERATIONAL IMPACT. LIKELY SHRA...TSRA. WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY SHRA...TSRA. THURSDAY: LOW OPERATIONAL IMPACT. ISOLATED SHRA...TSRA. THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... MAINLY DRY TODAY OUTSIDE OF THE ADIRONDACKS AND MOHAWK VALLEY WHERE SCATTERED SHOWERS AND POSSIBLE THUNDERSTORMS WILL TAKE PLACE. AFTERNOON RH VALUES WILL RANGE FROM AROUND 40 FROM ALBANY SOUTH AND EAST...BUT WILL REMAIN IN THE 50-60 PERCENT RANGE FURTHER NORTH AND WEST WHERE SHOWERS AND STORMS ARE MORE POSSIBLE. A GUSTY SOUTH WIND WILL BE 10 TO 20 MPH. A WET AND UNSETTLED PERIOD EXPECTED TONIGHT THROUGH EARLY THURSDAY. RH VALUES SHOULD INCREASE BACK TO NEAR 100 PERCENT TUESDAY NIGHT WITH SHOWERS AND THUNDERSTORMS. ON WEDNESDAY...MOST AREAS SHOULD SEE SHOWERS AND THUNDERSTORMS AND RH VALUES WILL ONLY DROP TO THE 60 TO 80 PERCENT RANGE. ALL AREAS ARE EXPECTED TO RECEIVE A QUARTER INCH OR MORE OF RAINFALL. A DRYING TREND EXPECTED LATER THURSDAY INTO THE WEEKEND. && .HYDROLOGY... SCATTERED SHOWERS AND THUNDERSTORMS MAINLY ACROSS THE ADIRONDACKS AND MOHAWK VALLEY TODAY. SOME OF THESE COULD PRODUCE LOCALLY HEAVY RAINFALL RESULTING WITH SOME PONDING OF WATER. ONLY AN OUTSIDE OF SHOWER OR THUNDERSTORM IS EXPECTED FURTHER SOUTH AND EAST. AS A SLOW MOVING COLD FRONT APPROACHES TOMORROW...AND ONE...IF NOT SEVERAL WAVES OF LOW PRESSURE DEVELOP ALONG IT...SHOWER AND THUNDERSTORM CHANCES INCREASE...TO LIKELY BY LATE TUESDAY NIGHT IN THE WESTERN MOHAWK VALLEY AND SOUTHERN ADIRONDACKS AND SCATTERED EVERYWHERE ELSE. BY WEDNESDAY...SHOWERS AND THUNDERSTORMS ARE LIKELY ACROSS THE REGION. SOME OF THE STORMS COULD PRODUCE LOCALLY HEAVY WITH POTENTIAL FOR PONDING OF WATER. WE ARE FORECASTING AN AVERAGE BASIN RAINFALL OF 1-2 INCHES OF RAINFALL ACROSS OUR FORECAST AREA. THIS COULD BE ENOUGH RAINFALL TO PRODUCE SOME SIGNIFICANT WITHIN BANK RISES ON SOME RIVERS AND STREAMS. A COUPLE SPOTS LIKE DELTA DAM AND UTICA COULD REACH ACTION STAGE. TRAINING THUNDERSTORMS CONTAINING HEAVY RAINFALL DO HAVE THE REMOTE POSSIBILITY OF PRODUCING FLASH FLOODING BUT RIGHT NOW...THE THREAT OF THAT WAS LOWER THAN 50 PERCENT SO NO FLASH FLASH FLOOD WATCHES WERE ISSUED ON THIS SHIFT. KEEP IN MIND ANY THUNDERSTORM COULD PRODUCE LOCAL AMOUNTS WELL OVER 2 INCHES. STAY TUNED. DRIER WEATHER WILL TAKE HOLD LATER THURSDAY INTO THE WEEKEND. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...HWJIV/NAS NEAR TERM...HWJIV/NAS SHORT TERM...HWJIV/NAS LONG TERM...GJM AVIATION...GJM FIRE WEATHER...HWJIV HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS ALBANY NY
630 AM EDT TUE JUN 24 2014 .SYNOPSIS... HIGH PRESSURE OFFSHORE WILL BRING SOUTHERLY WINDS WILL SLOWLY INCREASE OUR HUMIDITY. A COLD FRONT OVER THE OHIO VALLEY WILL BEGIN TO VERY SLOWLY APPROACH OUR REGION BY TONIGHT. THIS FRONT COULD TRIGGER SHOWERS AND THUNDERSTORMS MAINLY TO THE WEST OF THE CAPITAL REGION LATER TODAY. TONIGHT THROUGH EARLY THURSDAY...THE FRONT WILL SLOWLY DRAG THROUGH THE REGION...WITH WAVES OF LOW PRESSURE FORMING ALONG IT...WHICH WILL PRODUCE BOUTS OF SHOWERS AND POSSIBLE THUNDERSTORMS. ANY THUNDERSTORM COULD CONTAIN GUSTY WINDS AND HEAVY RAINFALL...ESPECIALLY WEDNESDAY AFTERNOON AND EVENING. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 630 AM EDT...SCATTERED TO NUMEROUS SHOWERS WERE WORKING ACROSS MUCH OF HERKIMER COUNTY. STILL...NO CLOUD TO GROUND LIGHTNING AND THE LATEST RUC AND MSAS ANALYSIS INDICATED LITTLE OR NO INSTABILITY. SO WE WILL CALL THESE SCATTERED THROUGH MID MORNING. THE SHOWERS LOOK TO EXIT AND THERE MIGHT BE A LULL BEFORE MORE SHOWERS AND STORMS FORM LATER TODAY. THE VAST MAJORITY OF THE REGION REMAINED DRY AND MILD AS A PERSISTENT SOUTHERLY BREEZE HAS KEPT TEMPERATURES MAINLY IN THE 60S AT THIS HOUR...WITH ONLY A FEW UPPER 50S IN THE SHELTERED MOUNTAIN VALLEYS. SO FOR THIS UPDATE...CHANGED SOME OF THE POP/WEATHER GRIDS BASED ON THE CURRENT RADAR TRENDS AND OF COURSE TWEAKED THE HOURLY GRIDS. TODAY...SUNSHINE WILL BE MIXED WITH A GOOD DEAL OF HIGH CLOUDS...IN THE CAPITAL REGION...LESS SO FURTHER SOUTH AND EAST. IT WILL BE MOSTLY TO TOTALLY CLOUDY FURTHER NORTH AND WEST. A SOUTH WIND WILL AVERAGE 10 TO 15 MPH...WITH GUSTS UP TO 25 TO PERHAPS EVEN 30 MPH AT TIMES. TEMPERATURES WILL ONCE AGAIN CLIMB WELL INTO THE 80S FROM THE CAPITAL REGION SOUTH AND EAST...WITH SOME LOCALITIES POSSIBLY REACHING THE UPPER 80S. FURTHER NORTH AND WEST...WITH THICKER CLOUDS...TEMPERATURES WILL NOT BE QUITE AS WARM...CLOSER TO 80. DEWPOINTS WILL SLOWLY CREEP THROUGH THE 50S...REACHING 60 OR HIGHER FROM THE CAPITAL REGION AND AREAS NORTH AND WEST. INSTABILITY WILL INCREASE AND THERE WILL LIKELY BE OLD OUTFLOW BOUNDARIES ACROSS THE MOHAWK VALLEY AND SOUTHERN ADIRONDACKS. ALL OF THE FACTORS WILL INCREASE THE CHANCE OF SHOWER AND THUNDERSTORM ACTIVITY. THE 0-6KM BULK SHEAR WILL INCREASE TO ABOUT 30KTS FROM THE SOUTHWEST. THUNDERSTORM THAT DO DEVELOP COULD END UP PRODUCING SOME GUSTY WINDS (PROBABLY SUBSEVERE) BUT A ROGUE SEVERE THUNDERSTORM IS POSSIBLE WITH A BOWING SEGMENT. PWATS RAMP TO NEARLY 2 INCHES...SO ANY THUNDERSTORM COULD HEAVY RAINFALL. WE CONTINUE TO USE ENHANCED WORDING IN OUR GRIDS NORTH AND WEST OF THE CAPITAL REGION. FROM ALBANY SOUTH AND EAST...WE ONLY GAVE SLIGHT POPS (ACTUALLY NONE SOUTHEAST OF ALBANY AS RIDGING ALOFT WILL LIKELY PREVENT ANY UPWARD MOTION AND RESULTANT SHOWERS AND STORMS. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... SINCE THE COLD FRONT WILL STILL BE OUR WEST TONIGHT...THUNDERSTORM ACTIVITY THAT DOES DEVELOP LATE IN THE DAY...MIGHT ACTUALLY DIMINISH OVERNIGHT..ALTHOUGH REMNANTS OF THOSE STORMS COULD CERTAINLY MOVE FURTHER EAST. DEWPOINTS WILL CLIMB INTO THE 60S EVERYWHERE MAKING IT A MUGGY NIGHT. LOWS WILL BE GENERALLY IN THE 60S...CLOSER TO 70 IN THE IMMEDIATE CAPITAL REGION. WEDNESDAY AND WEDNESDAY NIGHT...MORE ORGANIZED UPPER DYNAMICS...A LITTLE BOUNDARY LAYER WIND CORE...MUCH DEEPER MOISTURE AND SOME UPPER DIVERGENCE IS EXPECTED TO CONTRIBUTE TO AN ORGANIZED BAND OF THUNDERSTORMS AHEAD AND ALONG A COLD FRONT. INSTABILITY WILL LARGELY BE BASED AT THE SURFACE AS MIDLEVEL LAPSE RATES STILL DO NOT LOOK IMPRESSIVE. STILL ENOUGH INSTABILITY SO WE WILL HAVE TO WATCH FOR ISOLATED SEVERE WIND GUSTS...BUT MAYBE MORE OF A VERY HEAVY RAIN POTENTIAL BASED ON THE VERY ANOMALOUSLY HIGH PWAT VALUES AROUND TWO INCHES REGION WIDE. GUIDANCE WAS IN SLIGHTLY BETTER AGREEMENT WHERE THE AXIS OF HEAVIES RAINFALL WILL TAKE PLACE. THE REALLY MOST OF THE AREA LOOKS TO POTENTIALLY RECEIVE AN INCH OR BETTER OF RAINFALL. INITIALLY...NORTHERN AREAS WILL GET HIT EARLY WEDNESDAY...WITH THE AXIS SLOWLY SHIFTING SOUTH AND EAST LATE WEDNESDAY INTO EARLY THURSDAY. WE ARE STILL NOT READY TO ISSUE ANY FLASH FLOOD WATCHES YET...AS THE BULK OF THE RAIN WILL NOT FALL UNTIL LATER WEDNESDAY AND THE CONFIDENCE OF FLASH FLOODING IS BELOW 50 PERCENT DUE TO SOMEWHAT DRY CONDITIONS GOING INTO THIS EVENT. MORE ABOUT HYDROLOGICAL ISSUES CAN BE FOUND IN OUR HYDROLOGICAL SECTION. THERE ARE STILL INDICATIONS OF LINGERING UPPER ENERGY AND A LOW LEVEL FEATURE FOR ONE LAST ROUND OF LOW LEVEL FORCING AS THE COLD FRONT CONTINUES ITS PROGRESS EAST AND SOUTH. SO...LINGERING ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS THURSDAY MORNING IN MOST PLACES...BUT THROUGHOUT THE DAY IN THE MID HUDSON VALLEY AND NW CT. TEMPERATURES ON WEDNESDAY WILL HIGHLY DEPEND ON HOW CLOUDS IT REMAINS. THE 00Z NAM MOS NUMBERS WERE COOLER BASED ON MORE CLOUDS WHILE THE MAV MOS NUMBERS INDICATED PERHAPS A LITTLE MORE SUNSHINE. FOR NOW...WENT WITH THE MAV/MET MIX BUT LEANING TOWARD THE COOLER MET NUMBERS. THIS WOULD GIVE HIGHS CLOSE TO 80 AROUND THE CAPITAL REGION...LOWER TO MID 80S FURTHER SOUTH...70S WELL NORTH AND WEST. DEWPOINTS WILL BE HIGH HOLDING WELL INTO THE 60S. WEDNESDAY NIGHT LOWS WILL RANGE FROM THE UPPER 50S TO MID 60S. HIGHS THURSDAY WITH CLOUDS GIVING TO A FEW LATE TIME SUNNY BREAKS AND ONLY WEAK COLD AIR ADVECTION WILL RANGE FROM THE MID 70S NORTHWEST TO LOWER 80S SOUTH OF ALBANY. && .LONG TERM /FRIDAY THROUGH MONDAY/... BEHIND THE COLD FRONT THAT EXITS THE REGION THURSDAY NIGHT...EXPECT THE ENTIRE REGION TO ENJOY SOME TRANQUIL AND DRY WEATHER FRIDAY THROUGH SUNDAY NIGHT WITH MAINLY CLEAR TO PARTLY CLOUDY SKIES. AN INCREASINGLY MOIST SOUTHWEST FLOW OF AIR COULD BRING SOME SHOWERS AND TSTMS TO THE REGION ON MONDAY. TEMPERATURES WILL BE NEAR TO SLIGHT ABOVE NORMAL FRIDAY THROUGH MONDAY. HIGHS FRIDAY AND SATURDAY WILL BE IN THE 70S TO AROUND 80. LOWS FRIDAY AND SATURDAY NIGHTS IN THE 50S TO AROUND 60. GETTING WARMER ON SUNDAY WITH HIGHS IN THE MID 70S TO LOWER 80S. LOWS SUNDAY NIGHT IN THE MID 50S TO LOWER 60S. HIGHS MONDAY IN THE UPPER 70S TO MID 80S. && .AVIATION /10Z TUESDAY THROUGH SATURDAY/... A SLOW MOVING FRONTAL BOUNDARY WILL SLOWLY MOVE EAST FROM THE GREAT LAKES REGION ON TUESDAY. THERE WILL BE A SOUTHERLY FLOW AHEAD OF THIS SYSTEM...BUT AT THIS POINT FORECAST MODELS INDICATE THAT MOST OF THE SHOWERS/TSTMS ASSOCIATED WITH THIS FRONTAL BOUNDARY WILL REMAIN TO THE WEST OF THE TAF SITES THROUGH THE TAF PERIOD ENDING AT 06Z WEDNESDAY. AT KALB HAVE INDICATED VCSH IN THE FORECAST AFTER 23Z TUESDAY...AND AFTER 21Z AT KGFL. A BRIEF PERIOD OF VCSH HAS ALSO BEEN FORECAST FOR KGFL TUESDAY MORNING DUE TO A BATCH OF SHOWERS CURRENTLY MOVING EAST-NORTHEAST FROM LAKE ONTARIO. AT KPOU/KPSF... HAVE NOT FORECAST ANY THREAT OF PCPN. AS A RESULT...EXPECT VFR CONDITIONS AT THE TAF SITES THROUGH THE ENTIRE TAF PERIOD. WITH A SOUTHERLY FLOW OCCURRING AT ALL THE TAF SITES OVERNIGHT...AND WITH MID/HIGH CLOUDS SPREADING ACROSS THE REGION...THERE IS LITTLE CHANCE OF ANY FOG FORMATION TONIGHT AND HAVE NOT FORECAST ANY. SOUTH WINDS AT KGFL/KPSF/KPOU OVERNIGHT WILL GENERALLY BE 8 KTS OR LESS...BUT AT KALB THE SPEEDS WILL BE 10 TO 15 KTS WITH GUSTS OF AROUND 20 KTS. WIND SPEEDS WILL INCREASE AT ALL THE TAF SITES ON TUESDAY TO 10 TO 15 KTS WITH GUSTS OF 16 TO 22 KTS. WIND SPEEDS WILL DECREASE TO 5 TO 10 KTS TUESDAY NIGHT...WITH SOME GUSTS OVER 15 KTS AT KALB. OUTLOOK... TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHC SHRA...TSRA. WEDNESDAY: HIGH OPERATIONAL IMPACT. LIKELY SHRA...TSRA. WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY SHRA...TSRA. THURSDAY: LOW OPERATIONAL IMPACT. ISOLATED SHRA...TSRA. THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... MAINLY DRY TODAY OUTSIDE OF THE ADIRONDACKS AND MOHAWK VALLEY WHERE SCATTERED SHOWERS AND POSSIBLE THUNDERSTORMS WILL TAKE PLACE. AFTERNOON RH VALUES WILL RANGE FROM AROUND 40 FROM ALBANY SOUTH AND EAST...BUT WILL REMAIN IN THE 50-60 PERCENT RANGE FURTHER NORTH AND WEST WHERE SHOWERS AND STORMS ARE MORE POSSIBLE. A GUSTY SOUTH WIND WILL BE 10 TO 20 MPH. A WET AND UNSETTLED PERIOD EXPECTED TONIGHT THROUGH EARLY THURSDAY. RH VALUES SHOULD INCREASE BACK TO NEAR 100 PERCENT TUESDAY NIGHT WITH SHOWERS AND THUNDERSTORMS. ON WEDNESDAY...MOST AREAS SHOULD SEE SHOWERS AND THUNDERSTORMS AND RH VALUES WILL ONLY DROP TO THE 60 TO 80 PERCENT RANGE. ALL AREAS ARE EXPECTED TO RECEIVE A QUARTER INCH OR MORE OF RAINFALL. A DRYING TREND EXPECTED LATER THURSDAY INTO THE WEEKEND. && .HYDROLOGY... SCATTERED SHOWERS AND THUNDERSTORMS MAINLY ACROSS THE ADIRONDACKS AND MOHAWK VALLEY TODAY. SOME OF THESE COULD PRODUCE LOCALLY HEAVY RAINFALL RESULTING WITH SOME PONDING OF WATER. ONLY AN OUTSIDE OF SHOWER OR THUNDERSTORM IS EXPECTED FURTHER SOUTH AND EAST. AS A SLOW MOVING COLD FRONT APPROACHES TOMORROW...AND ONE...IF NOT SEVERAL WAVES OF LOW PRESSURE DEVELOP ALONG IT...SHOWER AND THUNDERSTORM CHANCES INCREASE...TO LIKELY BY LATE TUESDAY NIGHT IN THE WESTERN MOHAWK VALLEY AND SOUTHERN ADIRONDACKS AND SCATTERED EVERYWHERE ELSE. BY WEDNESDAY...SHOWERS AND THUNDERSTORMS ARE LIKELY ACROSS THE REGION. SOME OF THE STORMS COULD PRODUCE LOCALLY HEAVY WITH POTENTIAL FOR PONDING OF WATER. WE ARE FORECASTING AN AVERAGE BASIN RAINFALL OF 1-2 INCHES OF RAINFALL ACROSS OUR FORECAST AREA. THIS COULD BE ENOUGH RAINFALL TO PRODUCE SOME SIGNIFICANT WITHIN BANK RISES ON SOME RIVERS AND STREAMS. A COUPLE SPOTS LIKE DELTA DAM AND UTICA COULD REACH ACTION STAGE. TRAINING THUNDERSTORMS CONTAINING HEAVY RAINFALL DO HAVE THE REMOTE POSSIBILITY OF PRODUCING FLASH FLOODING BUT RIGHT NOW...THE THREAT OF THAT WAS LOWER THAN 50 PERCENT SO NO FLASH FLASH FLOOD WATCHES WERE ISSUED ON THIS SHIFT. KEEP IN MIND ANY THUNDERSTORM COULD PRODUCE LOCAL AMOUNTS WELL OVER 2 INCHES. STAY TUNED. DRIER WEATHER WILL TAKE HOLD LATER THURSDAY INTO THE WEEKEND. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...HWJIV/NAS NEAR TERM...HWJIV/NAS SHORT TERM...HWJIV/NAS LONG TERM...GJM AVIATION...GJM FIRE WEATHER...HWJIV HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
911 AM CDT Tue Jun 24 2014 ...Update to synopsis... .SYNOPSIS... ISSUED AT 911 AM CDT TUE JUN 24 2014 A minor upper level wave was moving across Colorado at 12Z. This feature was the partial impetus for scattered convection across the Colorado Plains and western Kansas this morning. The KDDC pwat was 1.07" this morning, or between the 50th/75th percentile. KDDC WSR-88D was indicating returned power this morning and also in regional radar mosaic. && .SHORT TERM...(Today and tonight) ISSUED AT 329 AM CDT TUE JUN 24 2014 At the time of this writing (just after 0830 UTC), a small mesoscale convective system (MCS) was slowly dissolving as it moved east-southeast across southwestern Kansas. There were other weakly organized storms across northwestern Kansas. There appeared to be a slow warming in infrared cold cloud tops associated with the western Kansas convection as we head toward the early morning hours. Water vapor and RAP analysis suggested a weak shortwave trough from southern Wyoming down into central Colorado. This feature will allow the redevelopment of the southeastern Colorado leeside low with south-southeast winds resuming by mid to late morning across portions of southwestern Kansas. Winds in the wake of this morning`s MCS will be light and one or two convergence zones will likely set up at the surface where south to southeast winds of 12 to 15 knots will converge into areas of weak or nearly calm winds over portions of west central and/or northwestern Kansas. These convergence areas at the surface will foster development of surface-based thunderstorms in the 20-22Z time frame just about anywhere across far east-central/southeast Colorado and/or western Kansas. The NAM12 shows a band of enhanced mid level flow from the west-northwest across eastern Colorado and western Kansas of 28 to 34 knots (500mb)...providing ample enough deep layer shear for supercell structures with the strongest discrete convection. Any supercell storms which develop would move almost due south given the mid level flow direction out of the west-northwest. It is unclear how long discrete thunderstorm phase will last, but back on Sunday there was a supercell storm that rolled south for 4+ hours (eastern Oklahoma Panhandle into the northeastern Texas Panhandle) before becoming absorbed by other convection and transitioning to an MCS. The CAPE/Shear profile does not look all that dissimilar from the Sunday event. Should a supercell storm form and thrive in this environment, maximum hail size of tennis balls will be possible (local research /Large Hail Parameter/ in the upper single digits also supports this maximum hail size). The thinking is that any such hail event of that size would be very isolated and probably brief with many of the hail reports being half dollar to 2-inch in diameter. We increased POPs to 60 percent and included "Heavy Rain" in the grids given the continued very moist environment and impressive QPF signals from the WRF high- resolution models...as well as the ECMWF. POPs may need to be increased further (to categorical/80+) later on today as mesoscale details emerge. .LONG TERM...(Wednesday through Monday) ISSUED AT 326 AM CDT TUE JUN 24 2014 A weak upper level ridge is progged to move through the Rockies Wednesday, then through the Plains Thursday before exiting stage right on Friday. Meanwhile, an upper level long wave trough is expected to move into the Pacific Northwest and Intermountain West Wednesday and Thursday then into the Northern Rockies and Northern Plains Friday into this weekend. A trough of low pressure at the surface will intensify across eastern Colorado as this feature approaches bringing southerly winds to western Kansas through the weekend. An exiting MCS may bring scattered thunderstorms to south central Kansas Wednesday morning but should exit the area by noon. A slight chance of thunderstorms will be possible late Wednesday afternoon into Wednesday night, otherwise expect mostly cloudy skies. Clouds decrease in coverage Thursday with partly cloudy skies expected through Saturday. A chance of thunderstorms will then be possible across northern Kansas and the I-70 corridor Saturday night as lift increases due to an upper level shortwave moving through across Nebraska. Otherwise expect a slight increase in cloud cover. Upper level ridging looks to build into the southern Rockies by the beginning of next week. This should suppress any significant weather across western Kansas with partly cloudy skies. Highs throughout the extended period start out in the upper 80s Wednesday with lower 90s expected Thursday through the weekend. Highs in the mid to upper 90s are possible early next week. Lows start out in the upper 60s Thursday morning with lower 70s anticipated through early next week. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) ISSUED AT 637 AM CDT TUE JUN 24 2014 VFR conditions will prevail this morning into this afternoon with scattered high clouds. Winds will generally be from the south at 10 knots increasing to 10 to 15 knots by late morning. Winds then shift to more of a southeasterly direction this afternoon. A chance of thunderstorms will be possible late this afternoon into the evening bringing brief periods of MVFR conditions. && .PRELIMINARY POINT TEMPS/POPS... DDC 85 65 87 67 / 60 60 20 30 GCK 85 64 87 67 / 60 60 20 30 EHA 84 64 90 66 / 60 50 20 30 LBL 87 64 90 68 / 60 60 20 30 HYS 80 64 85 67 / 40 40 20 30 P28 86 68 87 69 / 40 60 30 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...Sugden SHORT TERM...Umscheid LONG TERM...Hovorka_42 AVIATION...Hovorka_42
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
639 AM CDT Tue Jun 24 2014 ...Updated aviation section... .SHORT TERM...(Today and tonight) ISSUED AT 329 AM CDT TUE JUN 24 2014 At the time of this writing (just after 0830 UTC), a small mesoscale convective system (MCS) was slowly dissolving as it moved east-southeast across southwestern Kansas. There were other weakly organized storms across northwestern Kansas. There appeared to be a slow warming in infrared cold cloud tops associated with the western Kansas convection as we head toward the early morning hours. Water vapor and RAP analysis suggested a weak shortwave trough from southern Wyoming down into central Colorado. This feature will allow the redevelopment of the southeastern Colorado leeside low with south-southeast winds resuming by mid to late morning across portions of southwestern Kansas. Winds in the wake of this morning`s MCS will be light and one or two convergence zones will likely set up at the surface where south to southeast winds of 12 to 15 knots will converge into areas of weak or nearly calm winds over portions of west central and/or northwestern Kansas. These convergence areas at the surface will foster development of surface-based thunderstorms in the 20-22Z time frame just about anywhere across far east-central/southeast Colorado and/or western Kansas. The NAM12 shows a band of enhanced mid level flow from the west-northwest across eastern Colorado and western Kansas of 28 to 34 knots (500mb)...providing ample enough deep layer shear for supercell structures with the strongest discrete convection. Any supercell storms which develop would move almost due south given the mid level flow direction out of the west-northwest. It is unclear how long discrete thunderstorm phase will last, but back on Sunday there was a supercell storm that rolled south for 4+ hours (eastern Oklahoma Panhandle into the northeastern Texas Panhandle) before becoming absorbed by other convection and transitioning to an MCS. The CAPE/Shear profile does not look all that dissimilar from the Sunday event. Should a supercell storm form and thrive in this environment, maximum hail size of tennis balls will be possible (local research /Large Hail Parameter/ in the upper single digits also supports this maximum hail size). The thinking is that any such hail event of that size would be very isolated and probably brief with many of the hail reports being half dollar to 2-inch in diameter. We increased POPs to 60 percent and included "Heavy Rain" in the grids given the continued very moist environment and impressive QPF signals from the WRF high- resolution models...as well as the ECMWF. POPs may need to be increased further (to categorical/80+) later on today as mesoscale details emerge. .LONG TERM...(Wednesday through Monday) ISSUED AT 326 AM CDT TUE JUN 24 2014 A weak upper level ridge is progged to move through the Rockies Wednesday, then through the Plains Thursday before exiting stage right on Friday. Meanwhile, an upper level long wave trough is expected to move into the Pacific Northwest and Intermountain West Wednesday and Thursday then into the Northern Rockies and Northern Plains Friday into this weekend. A trough of low pressure at the surface will intensify across eastern Colorado as this feature approaches bringing southerly winds to western Kansas through the weekend. An exiting MCS may bring scattered thunderstorms to south central Kansas Wednesday morning but should exit the area by noon. A slight chance of thunderstorms will be possible late Wednesday afternoon into Wednesday night, otherwise expect mostly cloudy skies. Clouds decrease in coverage Thursday with partly cloudy skies expected through Saturday. A chance of thunderstorms will then be possible across northern Kansas and the I-70 corridor Saturday night as lift increases due to an upper level shortwave moving through across Nebraska. Otherwise expect a slight increase in cloud cover. Upper level ridging looks to build into the southern Rockies by the beginning of next week. This should suppress any significant weather across western Kansas with partly cloudy skies. Highs throughout the extended period start out in the upper 80s Wednesday with lower 90s expected Thursday through the weekend. Highs in the mid to upper 90s are possible early next week. Lows start out in the upper 60s Thursday morning with lower 70s anticipated through early next week. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) ISSUED AT 637 AM CDT TUE JUN 24 2014 VFR conditions will prevail this morning into this afternoon with scattered high clouds. Winds will generally be from the south at 10 knots increasing to 10 to 15 knots by late morning. Winds then shift to more of a southeasterly direction this afternoon. A chance of thunderstorms will be possible late this afternoon into the evening bringing brief periods of MVFR conditions. && .PRELIMINARY POINT TEMPS/POPS... DDC 85 65 87 67 / 60 60 20 30 GCK 85 64 87 67 / 60 60 20 30 EHA 84 64 90 66 / 60 50 20 30 LBL 87 64 90 68 / 60 60 20 30 HYS 80 64 85 67 / 40 40 20 30 P28 86 68 87 69 / 40 60 30 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Hovorka_42 AVIATION...Hovorka_42
AREA FORECAST DISCUSSION
NWS TOPEKA KS
609 AM CDT Tue Jun 24 2014 ...Update to aviation forecast discussion... .SHORT TERM...(Today and Tonight) Issued at 327 AM CDT TUE JUN 24 2014 Quiet weather was in place across the local forecast area early this morning with light winds, high clouds, and departing surface high pressure. Farther to the west in western KS and eastern CO, a loosely organized convective system was making slow eastward progression. This convection seemed tied to a weak upper disturbance that was making a very slow eastward progression out of CO and NM through weak flow aloft. Additional weak, but seemingly more well-defined upper waves were located over southern California and eastern Montana. While the CA wave will be slow to move east, it seems that the Montana system may dive southeast and possibly interact with the system in eastern Colorado by tonight. In terms of the local forecast and sensible weather through tonight, expect the area of showers and thunderstorms to continue with slow but steady eastward development. Generally speaking, the NMM, ARW, and HRRR seem to be handling the situation well through the day, which coincides fairly well with larger scale model guidance as well. This suggests that showers and a few storms may encroach upon the Highway 81 corridor by early afternoon and possibly build into far eastern KS by early evening. All indications suggest a tight instability gradient from east to west which also gradually progresses to the east with time. This should prevent the convection from developing more quickly east today even if a few cold pools push out from convection. As the instability does arrive, it will be rather meager, as will wind shear profiles, and even strong storms seem quite unlikely through tonight. All told, much of the area stands a good chance to see at least some precip by sunrise on Wednesday, although amounts may be spotty. Aside from precip, temperatures will be in the lower to middle 80s today, with some question in just how warm it will get depending largely on cloud cover as more widespread clouds could hold everyone in the lower 80s. Winds will be light through tonight and dewpoints will remain fairly comfortable...in the low to middle 60s. .LONG TERM...(Wednesday through Monday) Issued at 327 AM CDT TUE JUN 24 2014 A slow upper shortwave trough translates southeast over the CO Rockies and central plains on Wednesday afternoon. Position and timing from guidance was fairly similar in developing a swath of showers and thunderstorms across the CWA from the overnight into the afternoon hours. Ample southerly moisture transport is aided by PWAT values in excess of 1.6 inches through the period. Have increased chances across the area during the day, gradually tapering off west to east by Wednesday evening. Do not expect severe storms with main threat being heavy rain and flash flooding. Occasional showers and thunderstorms are expected from Thursday onward as weaker upper perturbations within the mean flow give much uncertainty where mesoscale boundaries or areas of lift are positioned for scattered convection to form. Similar to previous trends, late afternoon into early evening time frame during peak heating and minimal inhibition is likely. The weekend forecast, for the most part, appears dry Friday and Saturday with temporary ridging over the area. On Saturday, H5 flow begins to back and increase toward the southwest in response to a deepening upper trof across the western CONUS. By the late afternoon period, a moist and unstable airmass in place may trigger scattered thunderstorms along/ahead of a cold front stretched over central KS into south central NE. A few storms may be severe in proximity to the convergent boundary where surface based CAPE in excess of 3000 J/KG complements effective shear near 40 kts. Activity weakens as it progresses eastward by Sunday with some indication of redevelopment by late afternoon across east central areas. Otherwise trends from the GFS/ECMWF depict weak trofs rotating through the main wave as the frontal boundary becomes a focal point for additional scattered convection Sunday evening into Monday. Minor adjustments were made to temperatures in the extended. Insulation from cloud cover and rainfall Wednesday should hold highs to the low 80s throughout the afternoon. Sunshine returns Thursday as consensus guidance warrants increased highs in the mid and upper 80s. With ample sunshine and increased boundary layer mixing through the weekend, warming trend continues with highs in the upper 80s to low 90s by Monday. Overnight lows follow suit from the mid 60s Thursday to the low 70s Friday into Monday. && .AVIATION...(For the 12Z TAFs through 12Z Wednesday Morning) Issued at 605 AM CDT TUE JUN 24 2014 Current occasionally reduced visibility should be all VFR by 12Z. Then expect VFR through the TAF period aside from brief reduced conditions with any thunderstorm activity. Timing of ts through the TAF period has very low confidence. Expect morning precip to remain west of TAF sites although it could come close to MHK. Late day activity should be scattered and timing is very much in question due to lack of a strong focus for storms...so have taken a VCTS approach for several hours while it will more likely be a few periods of TS at/near TAF sites during the VCTS time frame. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Barjenbruch LONG TERM...Bowen AVIATION...Barjenbruch
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1158 AM EDT TUE JUN 24 2014 .UPDATE... CURRENT RADAR SHOWS AN AREA OF MODERATE RAIN WITH EMBEDDED HEAVIER ELEMENTS OVER THE TRI CITIES AND NORTHERN THUMB. THIS AREA IS ASSOCIATED WITH RIGHT ENTRANCE REGION UPPER LEVEL FORCING ALONG WITH LOW LEVEL CONVERGENCE ALONG A SURFACE TROUGH. SOUTH OF THIS...PRECIP IS LESS WIDESPREAD...BUT A FEW STRONGER SEGMENTS WITH VERY HEAVY RAIN AND GUSTY WINDS TO AROUND 30 KNOTS ARE NOTED. THE WESTERN EDGE OF THE STEADIER RAIN IS PROGRESSING SLOWLY BUT STEADILY EASTWARD AS THE INDIVIDUAL ELEMENTS MOVE NORTHEAST. THIS EASTWARD SHIFT IN THE PRECIP SHIELD WILL CONTINUE AS THE UPPER TROUGH CONTINUES TO LIFT NORTHEASTWARD. UPSTREAM RADAR MOSAIC SHOWS LOTS OF BREAKS IN THE PRECIP...LEADING TO SOME DOUBT IN THE COVERAGE OF PRECIP FROM THE METRO DETROIT COUNTIES TO THE OHIO BORDER THIS AFTERNOON. EXPECT THIS TO FILL IN SOMEWHAT THIS AFTERNOON...BUT THE BEST UPPER FORCING AND LOW LEVEL CONVERGENCE LOOKS TO FAVOR THE AREA NORTH OF METRO DETROIT AND SOUTH OF THE TRI CITIES...WHICH HAS THE GREATEST THREAT FOR HEAVY RAINFALL. STILL...GIVEN THE VERY MOIST ATMOSPHERE...CATEGORICAL POPS EVERYWHERE LOOK GOOD. MAIN HAZARD THIS AFTERNOON/EVENING WILL BE LOCALLY HEAVY RAINFALL...WITH SOME LOCALIZED FLOODING WITH TRAINING STORMS. CAN NOT RULE OUT A FEW STRONGER STORMS WITH GUSTY WINDS MAINLY FROM METRO DETROIT TO THE OHIO BORDER...BUT OVERALL LACK OF INSTABILITY WILL LIMIT THE THREAT. EXPECT PRECIP COVERAGE TO BEGIN A DOWNWARD TREND OVER THE TRI-CITIES BY MIDAFTERNOON. && .AVIATION...ISSUED 710 AM EDT TUE JUN 24 2014 //DISCUSSION... A BROAD AREA OF SHOWERS AND THUNDERSTORMS CONTINUES TO ORGANIZE FROM CENTRAL ILLINOIS INTO SW LOWER MICHIGAN AT PRESS TIME. THIS ACTIVITY WILL SPREAD THE REST OF THE WAY OVER SE MICHIGAN DURING THE MORNING AND THEN PERSIST MUCH OF THE AFTERNOON. THE SURFACE TROUGH OF LOW PRESSURE THAT IS HELPING TO FOCUS THE RAINFALL IS ALSO PRODUCING IFR FOG AND LOW CLOUDS AT MBS DOWN TO ABOUT FNT WHICH WILL SPREAD SOUTHWARD AS THE RAIN FILLS IN OVER THE REGION. A BRIEF RETURN TO ENTRY LEVEL VFR CONDITIONS IS EXPECTED DURING THE MID TO LATE AFTERNOON ALONG THE TRAILING EDGE OF THE RAIN AREA BUT THEN FILL BACK IN WITH FOG AND LOW CLOUDS AFTER SUNSET TONIGHT. IFR/LIFR CEILING AND IFR VISIBILITY IN FOG AND STRATUS WILL DEVELOP IN THE NEARLY CALM WIND AND MOIST SURFACE AIR LEFT BEHIND BY THE RAIN BUT AHEAD OF THE COLD FRONT THAT WILL MOVE DOWN FROM NORTHERN LOWER MICHIGAN AFTER MIDNIGHT THROUGH SUNRISE WEDNESDAY. COOLER AND LESS HUMID AIR WILL LEAD TO IMPROVEMENT DURING WEDNESDAY MORNING. FOR DTW... THE LATEST RADAR TREND AT PRESS TIME INDICATES THE HEAVIEST RAIN WILL SET UP INITIALLY TO THE WEST OF DTW...BUT THEN FILL IN TOWARD THE TERMINAL DURING THE LATE MORNING AND LAST THROUGH THE DAY. RAINFALL IN THE 1-2 INCH RANGE REMAINS ON TRACK FOR THE EVENT TOTAL. //DTW THRESHOLD THREATS... * HIGH CONFIDENCE IN CEILING BELOW 5000 FT TODAY AND TONIGHT. * MEDIUM CONFIDENCE IN THUNDERSTORM TIMING DURING THE AFTERNOON. && .PREV DISCUSSION...ISSUED 403 AM EDT TUE JUN 24 2014 SHORT TERM... TODAY AND TONIGHT COMPARED TO YESTERDAY...THE LARGER SCALE WEATHER FEATURES HAVE BECOME MORE ORGANIZED IF NOT STRONGER IN MAGNITUDE. THE RESULT WILL BE A WET DAY AROUND SE MICHIGAN. EXPECT SHOWERS AND THUNDERSTORMS TO BECOME WIDESPREAD DURING THE MORNING AND LAST THROUGH EARLY EVENING BEFORE DRIFTING EASTWARD OUT OF THE AREA. THE REST OF TONIGHT WILL BE CONCERNED WITH THE PROGRESS OF A TRAILING COLD FRONT THAT WILL MOVE THROUGH THE OHIO BORDER BY SUNRISE WEDNESDAY. SATELLITE IMAGERY AND MODEL ANALYSIS FIELDS INDICATE A WELL-DEFINED UPPER LEVEL TROUGH MOVING THROUGH THE MIDWEST AND MISSISSIPPI VALLEY DURING THE EARLY MORNING. THERE IS ALSO A DISTINCT JET MAX OVER THE GREAT LAKES WHERE THE TROUGH IS PHASING WITH THE NORTHERN STREAM CANADIAN TROUGH/LOW. THE ENTRANCE REGION OF THIS JET IS SETTING UP TO SUPPORT ENHANCED LIFT ALONG AND EAST OF THE TROUGH AXIS FROM THE MID MISSISSIPPI VALLEY INTO THE SOUTHERN GREAT LAKES. THESE UPPER LEVEL FEATURES ARE WELL-ALIGNED WITH THE SURFACE TROUGH AND LOW TO MID LEVEL MOISTURE AXIS CONSISTING OF 850 MB DEWPOINT AROUND 13C, 700 MB DEWPOINT AROUND 5C, AND PRECIPITABLE WATER APPROACHING 2 INCHES. THE RESULT IS A BROAD AREA OF SHOWERS AND THUNDERSTORMS FROM ARKANSAS INTO SOUTHERN LAKE MICHIGAN AT PRESS TIME WHICH WILL EXPAND NORTHEASTWARD THROUGH THE REST OF LOWER MICHIGAN DURING THE MORNING AND PERSIST THROUGH THE AFTERNOON. THE 00Z MODELS COLLECTIVELY HAVE A GOOD HANDLE ON THE BULK MASS AND MOISTURE FIELDS...BUT THE NAM AND RECENT RUNS OF THE RAP ARE MORE THAN A SERVICEABLE REPRESENTATION OF THE SW-NE ORIENTED BAND OF CONVECTION SETTING UP PARALLEL TO THE UPPER FLOW. FORECAST SOUNDINGS FROM THE NAM THROUGH BUFKIT ANALYSIS INDICATE MBE VECTORS ALIGNED WITH THE MEAN FLOW...WHICH IS A HEAVY RAINFALL SIGNATURE...BUT HIGH-RES RUNS OF THE HRRR AND WRF-NMM ARE MORE PROGRESSIVE AS IS THE LARGER SCALE PATTERN IN THE GFS AND ECMWF. THIS IS ENOUGH EVIDENCE TO HOLD OFF ON FLOOD HEADLINES FOR NOW BUT PLAN TO HIGHLIGHT HEAVY RAINFALL IN THE FORECAST WITH THE EXPECTATION OF 1-2 INCH TOTALS AND LOCALLY HIGHER AMOUNTS THROUGH THE DAY...MAINLY OVER THE SOUTH HALF OF SE MICHIGAN. THE SOUTHERN STREAM UPPER TROUGH WILL SLIDE EASTWARD TONIGHT AND TAKE THE RAIN SHIELD OUT OF SE MICHIGAN BY MID EVENING. THAT WILL LEAVE THE NORTHERN STREAM UPPER TROUGH/LOW TO PIVOT SOUTHWARD DURING THE REST OF THE NIGHT. SUBSIDENCE IN BETWEEN THESE TWO FEATURES WILL HELP DRY THINGS OUT FROM A RAINFALL PERSPECTIVE BUT BOUNDARY LAYER MOISTURE WILL REMAIN HIGH WITH WEAK GRADIENT FLOW SUPPORTING BOTH LOW CLOUDS AND FOG DURING THE OVERNIGHT HOURS. THE ASSOCIATED COLD FRONT WILL BRING A WIND SHIFT TO THE NORTHEAST IN THE SAGINAW VALLEY SHORTLY AFTER MIDNIGHT WHICH WILL PROGRESS SOUTHWARD DURING THE NIGHT BUT LOW LEVEL DRY ADVECTION WILL BE SLOW UNTIL AFTER SUNRISE. LONG TERM...WEDNESDAY THROUGH SUNDAY THE PSEUDO ZONAL UPPER LEVEL JET AXIS WILL BE IN THE PROCESS OF EXITING THE REGION ON WEDNESDAY. SOME FAIRLY BIG CHANGES IN THE MODEL GUIDANCE COMPARED TO 24 HOURS AGO. NWP IS NOW MORE UNIFORM/LESS NOISY IN BRINGING THE UPPER LEVEL DISTURBANCE OVER THE DAKOTAS DIRECTLY INTO LOWER MICHIGAN FOR THE AFTERNOON. IN ADDITION...ANOTHER FAVORABLE ZONE OF RIGHT ENTRANCE REGION DYNAMICS ARE EXPECTED TO SET UP SHOP OVER SOUTHEASTERN MICHIGAN WITH JET ENERGY THAT IS ASSOCIATED WITH THE AFOREMENTIONED UPPER LEVEL VORTICITY MAXIMUM. THIS CONCURRENT FORCING SHOULD ALWAYS GIVE ONE PAUSE AND CERTAINLY DOES HERE TOO. THE PROBLEM IS THE FORECASTED THERMODYNAMIC PROFILE IS EXPECTED TO BE STABLE WITH A SUBSIDENCE INVERSION CENTERED BETWEEN 700-600MB. THERE IS THE POTENTIAL TO BYPASS THIS FEATURE...WHICH WILL REQUIRE A HIGH AMOUNT OF BOUNDARY LAYER MOISTURE. NAM IS SUPPORTIVE OF THIS...BUT WITH IT/S HIGH BIAS IT/S NOT EXACTLY A STRONG ENDORSEMENT. WILL CONTINUE TO GO DRY HERE...AS THIS LOOKS LIKE A CALL FOR THE SHORT TERM. HIGH TEMPERATURES ARE EXPECTED TO RANGE IN THE 70S NORTH...TO NEAR 80 FOR THE HIGH SFC PRESSURE AREAS SOUTH AND EAST OF THE GLACIAL RIDGE. STRONG MID TO UPPER LEVEL GEOPOTENTIAL HEIGHT RISES WILL THEN LEAD TO STRONG SURFACE HIGH PRESSURE FOR THE END OF THE WEEK. NWP SIGNAL IN THE MODEL OUTPUT SUGGESTS THERE WILL ALSO BE A HEAVY COMPONENT FROM THE STABLE LAKE AGGREGATE. DRY WEATHER WITH A MODERATING AIRMASS SHOULD LEAD TO VERY FAVORABLE WEATHER CONDITIONS. AN EASTERLY FLOW TRAJECTORY SEEMS TO BE PLAYING SOME HAVOC WITH FORECASTED SFC TEMPERATURES...BUT READINGS SHOULD PUSH 80 DEGREES THURSDAY AND EXCEED 80 DEGREES BY FRIDAY. MARINE... ACTIVE STRETCH OF WEATHER WILL PERSIST INTO MID WEEK FOR THE EASTERN GREAT LAKES AS A PAIR OF FRONTS WORK THROUGH THE AREA. THE FIRST FRONT IS DRAPED ALONG A LINE FROM LAKE ONTARIO AND LAKE ERIE...SOUTHWEST INTO THE OHIO VALLEY AND WILL PRODUCE SHOWERS AND THUNDERSTORMS THROUGH THIS AFTERNOON. THIS WILL VEER WINDS FROM SOUTHERLY TO WESTERLY. A SECOND COLD FRONT WILL DROP SOUTHWARD OUT OF CANADA THROUGH THE CENTRAL GREAT LAKES TONIGHT WEDNESDAY...USHERING MODEST NORTHERLY WINDS DOWN THROUGH LAKE HURON. A WEAK PRESSURE GRADIENT WILL KEEP WINDS LIGHT THROUGH THE PERIOD...GENERALLY LESS THAN 15 KNOTS...WHICH IN TURN WILL KEEP WAVE HEIGHTS IN CHECK. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ UPDATE.......DT AVIATION.....BT SHORT TERM...BT LONG TERM....CB MARINE.......CB YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
710 AM EDT TUE JUN 24 2014 .AVIATION... //DISCUSSION... A BROAD AREA OF SHOWERS AND THUNDERSTORMS CONTINUES TO ORGANIZE FROM CENTRAL ILLINOIS INTO SW LOWER MICHIGAN AT PRESS TIME. THIS ACTIVITY WILL SPREAD THE REST OF THE WAY OVER SE MICHIGAN DURING THE MORNING AND THEN PERSIST MUCH OF THE AFTERNOON. THE SURFACE TROUGH OF LOW PRESSURE THAT IS HELPING TO FOCUS THE RAINFALL IS ALSO PRODUCING IFR FOG AND LOW CLOUDS AT MBS DOWN TO ABOUT FNT WHICH WILL SPREAD SOUTHWARD AS THE RAIN FILLS IN OVER THE REGION. A BRIEF RETURN TO ENTRY LEVEL VFR CONDITIONS IS EXPECTED DURING THE MID TO LATE AFTERNOON ALONG THE TRAILING EDGE OF THE RAIN AREA BUT THEN FILL BACK IN WITH FOG AND LOW CLOUDS AFTER SUNSET TONIGHT. IFR/LIFR CEILING AND IFR VISIBILITY IN FOG AND STRATUS WILL DEVELOP IN THE NEARLY CALM WIND AND MOIST SURFACE AIR LEFT BEHIND BY THE RAIN BUT AHEAD OF THE COLD FRONT THAT WILL MOVE DOWN FROM NORTHERN LOWER MICHIGAN AFTER MIDNIGHT THROUGH SUNRISE WEDNESDAY. COOLER AND LESS HUMID AIR WILL LEAD TO IMPROVEMENT DURING WEDNESDAY MORNING. FOR DTW... THE LATEST RADAR TREND AT PRESS TIME INDICATES THE HEAVIEST RAIN WILL SET UP INITIALLY TO THE WEST OF DTW...BUT THEN FILL IN TOWARD THE TERMINAL DURING THE LATE MORNING AND LAST THROUGH THE DAY. RAINFALL IN THE 1-2 INCH RANGE REMAINS ON TRACK FOR THE EVENT TOTAL. //DTW THRESHOLD THREATS... * HIGH CONFIDENCE IN CEILING BELOW 5000 FT TODAY AND TONIGHT. * MEDIUM CONFIDENCE IN THUNDERSTORM TIMING DURING THE AFTERNOON. && .PREV DISCUSSION...ISSUED 403 AM EDT TUE JUN 24 2014 SHORT TERM... TODAY AND TONIGHT COMPARED TO YESTERDAY...THE LARGER SCALE WEATHER FEATURES HAVE BECOME MORE ORGANIZED IF NOT STRONGER IN MAGNITUDE. THE RESULT WILL BE A WET DAY AROUND SE MICHIGAN. EXPECT SHOWERS AND THUNDERSTORMS TO BECOME WIDESPREAD DURING THE MORNING AND LAST THROUGH EARLY EVENING BEFORE DRIFTING EASTWARD OUT OF THE AREA. THE REST OF TONIGHT WILL BE CONCERNED WITH THE PROGRESS OF A TRAILING COLD FRONT THAT WILL MOVE THROUGH THE OHIO BORDER BY SUNRISE WEDNESDAY. SATELLITE IMAGERY AND MODEL ANALYSIS FIELDS INDICATE A WELL-DEFINED UPPER LEVEL TROUGH MOVING THROUGH THE MIDWEST AND MISSISSIPPI VALLEY DURING THE EARLY MORNING. THERE IS ALSO A DISTINCT JET MAX OVER THE GREAT LAKES WHERE THE TROUGH IS PHASING WITH THE NORTHERN STREAM CANADIAN TROUGH/LOW. THE ENTRANCE REGION OF THIS JET IS SETTING UP TO SUPPORT ENHANCED LIFT ALONG AND EAST OF THE TROUGH AXIS FROM THE MID MISSISSIPPI VALLEY INTO THE SOUTHERN GREAT LAKES. THESE UPPER LEVEL FEATURES ARE WELL-ALIGNED WITH THE SURFACE TROUGH AND LOW TO MID LEVEL MOISTURE AXIS CONSISTING OF 850 MB DEWPOINT AROUND 13C, 700 MB DEWPOINT AROUND 5C, AND PRECIPITABLE WATER APPROACHING 2 INCHES. THE RESULT IS A BROAD AREA OF SHOWERS AND THUNDERSTORMS FROM ARKANSAS INTO SOUTHERN LAKE MICHIGAN AT PRESS TIME WHICH WILL EXPAND NORTHEASTWARD THROUGH THE REST OF LOWER MICHIGAN DURING THE MORNING AND PERSIST THROUGH THE AFTERNOON. THE 00Z MODELS COLLECTIVELY HAVE A GOOD HANDLE ON THE BULK MASS AND MOISTURE FIELDS...BUT THE NAM AND RECENT RUNS OF THE RAP ARE MORE THAN A SERVICEABLE REPRESENTATION OF THE SW-NE ORIENTED BAND OF CONVECTION SETTING UP PARALLEL TO THE UPPER FLOW. FORECAST SOUNDINGS FROM THE NAM THROUGH BUFKIT ANALYSIS INDICATE MBE VECTORS ALIGNED WITH THE MEAN FLOW...WHICH IS A HEAVY RAINFALL SIGNATURE...BUT HIGH-RES RUNS OF THE HRRR AND WRF-NMM ARE MORE PROGRESSIVE AS IS THE LARGER SCALE PATTERN IN THE GFS AND ECMWF. THIS IS ENOUGH EVIDENCE TO HOLD OFF ON FLOOD HEADLINES FOR NOW BUT PLAN TO HIGHLIGHT HEAVY RAINFALL IN THE FORECAST WITH THE EXPECTATION OF 1-2 INCH TOTALS AND LOCALLY HIGHER AMOUNTS THROUGH THE DAY...MAINLY OVER THE SOUTH HALF OF SE MICHIGAN. THE SOUTHERN STREAM UPPER TROUGH WILL SLIDE EASTWARD TONIGHT AND TAKE THE RAIN SHIELD OUT OF SE MICHIGAN BY MID EVENING. THAT WILL LEAVE THE NORTHERN STREAM UPPER TROUGH/LOW TO PIVOT SOUTHWARD DURING THE REST OF THE NIGHT. SUBSIDENCE IN BETWEEN THESE TWO FEATURES WILL HELP DRY THINGS OUT FROM A RAINFALL PERSPECTIVE BUT BOUNDARY LAYER MOISTURE WILL REMAIN HIGH WITH WEAK GRADIENT FLOW SUPPORTING BOTH LOW CLOUDS AND FOG DURING THE OVERNIGHT HOURS. THE ASSOCIATED COLD FRONT WILL BRING A WIND SHIFT TO THE NORTHEAST IN THE SAGINAW VALLEY SHORTLY AFTER MIDNIGHT WHICH WILL PROGRESS SOUTHWARD DURING THE NIGHT BUT LOW LEVEL DRY ADVECTION WILL BE SLOW UNTIL AFTER SUNRISE. LONG TERM...WEDNESDAY THROUGH SUNDAY THE PSEUDO ZONAL UPPER LEVEL JET AXIS WILL BE IN THE PROCESS OF EXITING THE REGION ON WEDNESDAY. SOME FAIRLY BIG CHANGES IN THE MODEL GUIDANCE COMPARED TO 24 HOURS AGO. NWP IS NOW MORE UNIFORM/LESS NOISY IN BRINGING THE UPPER LEVEL DISTURBANCE OVER THE DAKOTAS DIRECTLY INTO LOWER MICHIGAN FOR THE AFTERNOON. IN ADDITION...ANOTHER FAVORABLE ZONE OF RIGHT ENTRANCE REGION DYNAMICS ARE EXPECTED TO SET UP SHOP OVER SOUTHEASTERN MICHIGAN WITH JET ENERGY THAT IS ASSOCIATED WITH THE AFOREMENTIONED UPPER LEVEL VORTICITY MAXIMUM. THIS CONCURRENT FORCING SHOULD ALWAYS GIVE ONE PAUSE AND CERTAINLY DOES HERE TOO. THE PROBLEM IS THE FORECASTED THERMODYNAMIC PROFILE IS EXPECTED TO BE STABLE WITH A SUBSIDENCE INVERSION CENTERED BETWEEN 700-600MB. THERE IS THE POTENTIAL TO BYPASS THIS FEATURE...WHICH WILL REQUIRE A HIGH AMOUNT OF BOUNDARY LAYER MOISTURE. NAM IS SUPPORTIVE OF THIS...BUT WITH IT/S HIGH BIAS IT/S NOT EXACTLY A STRONG ENDORSEMENT. WILL CONTINUE TO GO DRY HERE...AS THIS LOOKS LIKE A CALL FOR THE SHORT TERM. HIGH TEMPERATURES ARE EXPECTED TO RANGE IN THE 70S NORTH...TO NEAR 80 FOR THE HIGH SFC PRESSURE AREAS SOUTH AND EAST OF THE GLACIAL RIDGE. STRONG MID TO UPPER LEVEL GEOPOTENTIAL HEIGHT RISES WILL THEN LEAD TO STRONG SURFACE HIGH PRESSURE FOR THE END OF THE WEEK. NWP SIGNAL IN THE MODEL OUTPUT SUGGESTS THERE WILL ALSO BE A HEAVY COMPONENT FROM THE STABLE LAKE AGGREGATE. DRY WEATHER WITH A MODERATING AIRMASS SHOULD LEAD TO VERY FAVORABLE WEATHER CONDITIONS. AN EASTERLY FLOW TRAJECTORY SEEMS TO BE PLAYING SOME HAVOC WITH FORECASTED SFC TEMPERATURES...BUT READINGS SHOULD PUSH 80 DEGREES THURSDAY AND EXCEED 80 DEGREES BY FRIDAY. MARINE... ACTIVE STRETCH OF WEATHER WILL PERSIST INTO MID WEEK FOR THE EASTERN GREAT LAKES AS A PAIR OF FRONTS WORK THROUGH THE AREA. THE FIRST FRONT IS DRAPED ALONG A LINE FROM LAKE ONTARIO AND LAKE ERIE...SOUTHWEST INTO THE OHIO VALLEY AND WILL PRODUCE SHOWERS AND THUNDERSTORMS THROUGH THIS AFTERNOON. THIS WILL VEER WINDS FROM SOUTHERLY TO WESTERLY. A SECOND COLD FRONT WILL DROP SOUTHWARD OUT OF CANADA THROUGH THE CENTRAL GREAT LAKES TONIGHT WEDNESDAY...USHERING MODEST NORTHERLY WINDS DOWN THROUGH LAKE HURON. A WEAK PRESSURE GRADIENT WILL KEEP WINDS LIGHT THROUGH THE PERIOD...GENERALLY LESS THAN 15 KNOTS...WHICH IN TURN WILL KEEP WAVE HEIGHTS IN CHECK. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....BT SHORT TERM...BT LONG TERM....CB MARINE.......CB YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS HASTINGS NE
620 AM CDT TUE JUN 24 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 405 AM CDT TUE JUN 24 2014 MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND TEMPERATURES. CURRENT SURFACE ANALYSIS HAS A RIDGE OF HIGH PRESSURE ACROSS THE AREA EARLY THIS MORNING. SURROUNDING RADARS SHOW SHOWERS AND THUNDERSTORMS ON THE HIGH PLAINS GRADUALLY MOVING TOWARDS THE EAST. THE SURFACE HIGH IS EXPECTED TO MOVE OFF TO THE EAST. AN UPPER LEVEL WAVE IS EXPECTED TO MOVE INTO THE AREA DURING THE DAY. EXPECT THE CURRENT PRECIPITATION TO CONTINUE TO MOVE TO THE EAST AND INTO THE AREA BY DAYLIGHT. THE THUNDERSTORMS WILL CONTINUE TO MOVE ACROSS THE AREA DURING THE MORNING HOURS AND INTO THE AFTERNOON. THE HRRR AND THE 4KM WRF BOTH HAVE THE MAIN BAND OF THUNDERSTORMS MAINLY THROUGH THE FORECAST AREA BY MID AFTERNOON. THE MAIN DIFFERENCE IS THAT THE HRRR BRINGS IN ANOTHER BAND LATER THIS AFTERNOON. HAVE KEPT CHANCES IN DURING THE LATE AFTERNOON AND INTO THE NIGHT TIME HOURS. SEVERAL TIMES LATELY THERE HAVE BEEN MORE THUNDERSTORMS THAT DEVELOP ON THE HIGH PLAINS DURING THE AFTERNOON. THE THUNDERSTORMS MOVE INTO THE FORECAST AREA LATE EVENING AND OVERNIGHT. THE MUCAPE IS BEST DURING THE AFTERNOON BUT A LITTLE REMAINS THROUGH THE NIGHT. EXPECT THERE COULD BE A STRONG STORM OR TWO AROUND THE AREA THIS AFTERNOON AND EVENING...THEN TURN INTO A RAIN EVENT DURING THE NIGHT TIME HOURS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 405 AM CDT TUE JUN 24 2014 THE BIGGEST CHALLENGE WILL BE DETERMINING CHANCES OF RAIN IN THE LONG TERM. THE ZONAL FLOW WILL GRADUALLY BECOME MORE SOUTHWEST AS AN UPPER LEVEL TROUGH MOVES INTO THE WESTERN UNITED STATE. THIS WILL HELP KICK UP PULSES OF ENERGY INTO THE HIGH/GREAT PLAINS THAT WILL GIVE US A SHOT A SHOWER/THUNDERSTORMS FOR MOST PERIODS OF THE LONG TERM. THE GREATEST CHANCE OF RAIN WILL BE FRIDAY NIGHT AS A WARM FRONT MOVES IN AND THROUGH THE AREA...ALONG WITH AN INCREASED LOW- LEVEL JET AND POTENTIAL STRONG CONVERGENCE NEAR THE NOSE OF THE JET NEARBY. STRONG TO SEVERE STORMS CAN NOT BE RULED OUT...JUDGING BY SEVERE PARAMETERS...FOR MUCH OF THE LONG TERM...BUT NARROWING DOWN A DAY THAT IT WOULD BE MORE LIKELY IS TOO DIFFICULT TO IDENTIFY NOW. TEMPERATURES APPEARED TO BE PRETTY MUCH ON TRACK FROM THE PREVIOUS FORECAST...SO NO MAJOR CHANGES TO TEMPERATURES. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 609 AM CDT TUE JUN 24 2014 THUNDERSTORM CHANCES ARE THE CHALLENGE FOR TODAY. A BAND OF THUNDERSTORMS TO THE WEST OF THE TERMINAL AREA SHOULD MOVE INTO THE AREA IN A FEW HOURS. THE BIG QUESTION IS WHETHER THERE WILL BE A BREAK THIS AFTERNOON AND MORE THUNDERSTORMS TONIGHT OR WHETHER THERE WILL BE MORE THUNDERSTORMS DURING THE DAY WITH LESS DURING THE NIGHT TONIGHT. HAVE KEPT SOME VCTS DURING THE DAY BUT WILL HAVE TO KEEP AN EYE ON THE THUNDERSTORM ACTIVITY. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...JCB LONG TERM...HEINLEIN AVIATION...JCB
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
542 AM MDT TUE JUN 24 2014 .AVIATION... 12Z TAF CYCLE CLUSTER OF STORMS NEAR THE TX LINE WILL MOVE EAST INTO TX BY ABOUT SUNRISE. DEVELOPING SFC LOW OVER SE COLORADO WILL TURN/BACK WINDS TO SWLY OVER THE EASTERN PLAINS BY AFTERNOON...BRINGING DRIER AIR IN FROM WRN NM. MAIN STORM ACTIVITY TODAY EXPECTED FROM THE EAST SLOPES OF THE NORTHERN SANGRE DE CRISTO MTNS EWD TO THE FAR NE PLAINS. A FEW STRONG TO SEVERE STORMS POSSIBLE THIS AFTERNOON AND EVENING IN UNION AND COLFAX COUNTIES. ISOLD MAINLY DRY SHOWERS OR STORMS EXPECTED ELSEWHERE EAST OF THE CENTRAL MTN CHAIN THIS AFTERNOON AND EVENING WITH SKC OR A FEW FAIR WEATHER CUMULUS WEST. 33 && .PREV DISCUSSION...337 AM MDT TUE JUN 24 2014... .SYNOPSIS... AN ACTIVE WEATHER PATTERN WILL CONTINUE MAINLY FROM THE CENTRAL MOUNTAIN CHAIN EAST TO THE TEXAS BORDER. THIS INCLUDES THE POTENTIAL FOR STRONG TO SEVERE THUNDERSTORMS ACROSS PARTS OF THE EAST WITH THE FOCUS FOR SEVERE WEATHER SHIFTING TO THE NORTHEAST PLAINS LATER TODAY INTO EVENING. AFTER TONIGHT... A GRADUAL DRYING TREND IS EXPECTED FOR MID TO LATE WEEK WITH A MOSTLY DRY FORECAST FOR THURSDAY THROUGH SUNDAY. WE CANNOT RULE OUT ISOLATED THUNDERSTORMS FOR THE NORTHERN MOUNTAINS OR FAR EASTERN PLAINS FOR THE SECOND HALF OF THE WEEK...BUT HOTTER AND DRIER CONDITIONS WILL PREDOMINATE. && .DISCUSSION... MONITORING STRONG TO SEVERE CONVECTION ACROSS PARTS OF THE NORTHEAST AND EAST CENTRAL PLAINS EARLY THIS MORNING. EARLY STAGES OF A DEVELOPING MESOSCALE CONVECTIVE COMPLEX UNDERWAY NORTHWEST OF TUCUMCARI THAT IS SIMILAR TO WHAT THE LATEST 13KM RAP AND 03Z HRRR ADVERTISED IF NOT A LITTLE FARTHER SOUTH. SHALLOW SHORTWAVE TROUGH TRANSLATING EASTWARD COUPLED WITH A BROAD REGION OF UPPER LEVEL DIFLUENCE AIDING THIS EARLY MORNING DEVELOPMENT THAT IS ALIGNED ALONG A NW-SE ORIENTED SURFACE BOUNDARY WITH A STRONG/WELL- DEFINED MOISTURE/INSTABILITY GRADIENT STRETCHING FROM NORTH OF SANTA ROSA SEWD TOWARD THE LUBBOCK AREA. MADE SOME ADJUSTMENTS TO POP/WX GRIDS BUT WILL LIKELY REVISIT JUST BEFORE PUBLISHING. TRENDS AFTER THIS MORNING/S CONVECTIVE COMPLEX WEAKENS AND/OR EXITS TO THE EAST BETWEEN 13Z-15Z WILL BE MORE COMPLICATED... AS WESTWARD-PUSHING OUTFLOW BOUNDARIES MAY REINFORCE LOW LEVEL MOISTURE FIELDS A BIT FARTHER WEST THAN PREVIOUSLY EXPECTED. REGARDLESS... ANY LOW LEVEL MOISTURE WEST OF THE CENTRAL MOUNTAIN CHAIN WILL REMAIN QUITE SHALLOW AND WITH MID- LEVEL DRYING AND SOME LARGE-SCALE SUBSIDENCE DO NOT ANTICIPATE ANY NEED FOR EXPANSION OF ISOLATED POPS EAST OF THE DIVIDE THE RIO GRANDE. DID BEEF UP POPS FOR SC AREAS AS WELL AS THE FAR NE WHERE LOW LEVEL WINDS MAY GRADUALLY BACK TO MORE EASTERLY LATE IN THE DAY INCREASING POTENTIAL FOR SEVERE THERE. LESS ACTIVE TONIGHT INTO WED AM AS MID-LEVEL DRYING ADVANCES EASTWARD BENEATH A GENERAL WESTERLY FLOW REGIME WITH LESS DEFINED INDICATORS FOR LARGE SCALE UPWARD FORCING. EXPECT TO SEE A FAIRLY WELL DEFINED SURFACE DRYLINE WED PM NEAR THE NM/TX LINE WITH A DEEPENING SURFACE LOW OVER SE COLO. THE GFS DEVELOPS A WEAKER SURFACE LOW FARTHER SOUTH...WHICH WOULD AGAIN FAVOR THE FAR NE PLAINS FOR ANOTHER SHOT AT SEVERE BUT OVERALL COVERAGE OF STORMS TRENDING WAY DOWN SAVE FOR AREAS NEAR THE TX LINE AND POSSIBLY NE CORNER. EVEN DRIER/LESS ACTIVE WITH INCREASED WINDINESS FOR THU WITH AGAIN THE FOCUS FOR STORMS NEAR THE NM/TX LINE ALONG THE DRYLINE. BROAD CYCLONIC FLOW SPREADS EASTWARD OVER THE SOUTHERN ROCKIES AND NEW MEXICO BY FRIDAY WITH DRYLINE REGIME PERSISTING. 500MB HEIGHTS THEN REBOUND INTO THE WEEKEND WITH STRONGER RIDGE PATTERN EARLY NEXT WEEK. SHOULD LOSE INFLUENCE OF THE WESTERLIES BY MON/TUE...AND SIGNS THAT IT MAY PERSIST. KJ && .FIRE WEATHER... SIMILAR WEATHER SCENARIO TO MONDAY EXPECTED TODAY. BEST CHANCES FOR SHOWERS AND THUNDERSTORMS REMAINS EAST OF THE CENTRAL MOUNTAIN CHAIN WITH SLIGHTLY LESS ACTIVITY THAN MONDAY AS A SURFACE LOW BEGINS TO DEVELOP OVER SE COLORADO THIS AFTERNOON AND DRY AIR FROM THE WEST BEGINS TO WORK INTO THE CENTRAL AND NORTHEAST HIGHLANDS. WINDS BECOME MORE SOUTHWESTERLY WEDNESDAY...SCOURING OUT MORE GULF MOISTURE FROM THE SOUTHEAST AND EAST-CENTRAL PLAINS WITH SHOWERS AND STORMS PRIMARILY CONFINED TO THE FAR NE PLAINS. DRY WESTERLIES WIN OUT AREAWIDE BY THURSDAY AS LEE SFC TROUGH STRENGTHENS FURTHER. DRY CONDITIONS CONTINUE THROUGH THE WEEKEND ALONG WITH HIGH HAINES VALUES AND GOOD TO EXCELLENT VENTILATION RATES. WEST WINDS INCREASE FRIDAY AS A WEAK UPPER LEVEL TROUGH MOVES EAST THROUGH THE CENTRAL AND NORTHERN ROCKIES FRIDAY NIGHT INTO SATURDAY. CRITICAL FIRE WEATHER CONDITIONS ARE A POSSIBILITY FRIDAY AFTERNOON AND EARLY EVENING...PRIMARILY FROM THE CENTRAL HIGHLANDS NORTHEASTWARD TO THE NORTHEAST PLAINS. GFS AND ECMWF ARE GOOD AGREEMENT THAT WE FINALLY LOSE THE WESTERLIES ALOFT SUNDAY INTO EARLY NEXT WEEK. FOUR CORNERS HIGH BEGINS TO STRENGTHEN AND DRIFT NORTHWARD OVER SOUTHERN AZ AND SW NM SUNDAY...THEN OVER CENTRAL NM MONDAY. SUNDAY APPEARS TO BE THE HOTTEST DAY DURING THE NEXT 7 DAYS AS THE FOUR CORNERS HIGH MOVES OVERHEAD. MODELS HINTING THAT MONSOON MOISTURE MAY BEGIN TO SEEP NORTHWARD INTO PORTIONS OF SOUTHERN AND PERHAPS CENTRAL NM MONDAY AND TUESDAY. 33 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 41
AREA FORECAST DISCUSSION
NWS RALEIGH NC
748 AM EDT TUE JUN 24 2014 .SYNOPSIS...HIGH PRESSURE EXTENDING INTO OUR REGION FROM OFFSHORE THE NEW ENGLAND COAST WILL MOVE AWAY TODAY...AND YIELD TO A SURFACE PRESSURE TROUGH THAT WILL DEVELOP OVER THE WESTERN CAROLINAS THIS AFTERNOON. THE TROUGH WILL STRENGTHEN AND SHIFT EAST INTO THE CENTRAL AND EASTERN CAROLINAS FOR WEDNESDAY AND THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 740 AM TUESDAY... SHORTWAVE MID LEVEL RIDGING OVER THE MIDDLE ATLANTIC STATES...AND 1024 MB SURFACE HIGH PRESSURE OFF THE NEW ENGLAND COAST...WILL BOTH DRIFT EAST AND LOSE INFLUENCE OVER CENTRAL NC TODAY. A ROUGHLY EAST- WEST ORIENTED TROUGH AXIS IN THE H7-925 LAYER OVER THE SAVANNAH BASIN...WHICH INCLUDES THE OLD LOW LEVEL FRONTAL ZONE THAT CROSSED CENTRAL NC OVER THE WEEKEND...WILL LIFT NORTHWARD INTO SOUTHERN NC THIS AFTERNOON...AND ACROSS CENTRAL NC TONIGHT. THIS FEATURE AND ASSOCIATED CONVERGENCE/LIFT/MOISTURE POOLING WILL BE THE FOCUS FOR SCATTERED TO NUMEROUS SHOWERS AND STORMS FROM SC NORTHWARD INTO THE NC SANDHILLS AND SOUTHERN-WESTERN NC PIEDMONT AS EARLY AS LATE MORNING PER LATEST OBSERVATIONAL TRENDS AND HRRR GUIDANCE. GENERALLY SOUTHERLY LOW-MID LEVEL STEERING FLOW MAY ALLOW A MULTI-CELL CLUSTER OR TWO TO PROPAGATE NORTH...IN A PROGRESSIVELY WEAKENING STATE...ACROSS THE REMAINDER OF THE PIEDMONT THROUGH EARLY EVENING. MID LEVEL LAPSE RATES OF 5.25-5.5 C/KM AND ASSOCIATED WEAK MLCAPE OF 1500 J/KG AND MOSTLY LESS...AND WEAK FLOW THROUGHOUT THE TROPOSPHERE...WILL LIMIT STORM INTENSITY; SO SEVERE STORMS ARE NOT ANTICIPATED. GENERALLY PERSISTENCE HIGH TEMPS...EXCEPT UP TO A FEW DEGREES WARMER THAN THOSE OF MON IN THE COASTAL PLAIN...IN THE MIDDLE 80S TO AROUND 90 DEGREES. THE PASSAGE OF THE AFOREMENTIONED LOW-MID LEVEL TROUGH AXIS THROUGH AN ENVIRONMENT CHARACTERIZED BY LINGERING WEAK INSTABILITY AND MINIMAL CINH OVER CENTRAL NC...AS WELL AS THE APPROACH OF AN MCV CENTERED OVER THE WESTERN FL PANHANDLE THIS MORNING...WARRANT A SLIGHT-SMALL CHANCE A SHOWER OR STORM OVERNIGHT...ESPECIALLY OVER THE NE PIEDMONT AND COASTAL PLAIN. LOWS IN THE UPPER 60S TO LOWER 70S...WITH AREAS OF STRATUS LIKELY TO EXPAND OVER THE AREA LATE. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 315 AM TUESDAY... THE SHORTWAVE TROUGH AXIS INVOF THE MS RIVER THIS MORNING WILL MOVE EAST...ACROSS THE CENTRAL APPALACHIANS AND CAROLINAS WITH ASSOCIATED 10-20 METER MID LEVEL HEIGHT FALLS...WED-WED NIGHT. MEANWHILE AT THE SURFACE...A PRONOUNCED LEE TROUGH AND POSSIBLE LEE LOW WILL STRENGTHEN AND DRIFT EAST ACROSS CENTRAL NC/VA WED AFTERNOON AND INTO EASTERN NC/VA WED NIGHT. THE LEE TROUGH AND OROGRAPHIC CIRCULATIONS WILL LIKELY TRIGGER STORMS BY EARLY AFTERNOON. AROUND 20 KTS OF MID LEVEL FLOW AND COLD POOL MERGERS WILL THEN SUPPORT A GENERAL ENE PROPAGATION OF MULTI-CELL CLUSTERS ACROSS CENTRAL NC DURING THE AFTERNOON AND EVENING HOURS. THOUGH MID LEVEL LAPSE RATES ARE FORECAST TO REMAIN RELATIVELY WEAK - LESS THAN 5.75 C/KM - STEEP LOW LEVEL LAPSE RATES WILL FAVOR THE DEVELOPMENT OF STRONG TO MARGINALLY SEVERE DOWNBURST WINDS...PARTICULARLY IN ASSOCIATION WITH THE MORE ORGANIZED MULTI-CELL CLUSTERS/COLD POOLS. STORMS SHOULD MOVE EAST OF OUR AREA WITH THE PASSAGE OF THE AFOREMENTIONED LEE TROUGH AXIS OVERNIGHT...LINGERING LONGEST THROUGH AROUND MIDNIGHT TO 3 AM IN THE COASTAL PLAIN. WARMER WITH HIGHS IN THE UPPER 80S TO LOWER 90S. LOWS AGAIN IN THE UPPER 60S TO LOWER 70S. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 240 AM TUESDAY... GUIDANCE SUGGESTS THAT PRECIP CHANCES ACROSS CENTRAL NC WILL TREND DOWNWARD ON THURSDAY...AND REMAIN BELOW CLIMO ON FRIDAY...AS THE SFC BOUNDARY STALLS TO OUR EAST ON THURSDAY AND DRIER AIR MOVES IN FROM THE WEST IN THE WAKE OF THE MID-LEVEL TROUGH AXIS PASSING BY TO OUR EAST AND NORTHEAST (24 HOUR CLIMO POP FOR CENTRAL NC IS AROUND 30 PERCENT). RIGHT NOW...LOOKS LIKE THE BETTER CHANCE FOR A DRY DAY WILL BE THURSDAY...BECAUSE BY LATE FRIDAY...THE SFC TROUGH WILL BECOME REFOCUSED ACROSS THE PIEDMONT AND PWAT WILL BE BACK ON THE INCREASE. OVER THE WEEKEND...THE CHANCE FOR RAIN WILL INCREASE TO OR ABOVE CLIMO...AS A BACKDOOR FRONT APPROACHES FROM THE NORTH. THE RISK FOR SCATTERED SHOWERS AND TSTMS WILL CONTINUE ON MONDAY AS THE AFOREMENTIONED BOUNDARY REMAINS INVOF OUR CWA...AND AMPLE MOISTURE WILL REMAIN POOLED ACROSS THE AREA. ITS WORTH NOTING THAT DURING THE ENTIRE LONG TERM PERIOD...BULK SHEAR ISN`T THAT IMPRESSIVE...SO WHILE DAYTIME INSTABILITY MAY BE PLENTIFUL AND WE CAN NEVER RULE OUT THE POTENTIAL FOR AN ISOLATED STRONG-TO-SEVERE TSTM THIS TIME OF YEAR...BULK SHEAR PARAMETERS ACROSS CENTRAL NC ARE NOT FAVORABLE FOR ORGANIZED OR WIDESPREAD SEVERE CONVECTION DURING THIS TIME. AS FOR TEMPS...LATEST MEX SHOWS TEMPS CLIMBING ABOVE NORMAL THURSDAY THROUGH SATURDAY WITH HIGHS IN THE MID 90S AND LOWS NEAR 70. HOWEVER...FORECAST LOW LEVEL THICKNESSES ARE FAIRLY CLOSE TO NORMAL (1410-1420M)...SO WILL LEAN TOWARD THE COOLER SIDE OF THE GUIDANCE ENVELOPE FOR THIS TIME. TEMPS SHOULD TREND COOLER LATE IN THE WEEKEND INTO EARLY NEXT WEEK WITH INCREASED CLOUD COVERAGE AND RAIN CHANCES. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 748 AM TUESDAY... SSE FLOW JUST ABOVE THE SURFACE...IN RETURN FLOW AROUND OFFSHORE HIGH PRESSURE...HAS RESULTED IN SCT TO BKN MVFR RANGE CLOUD COVER THIS MORNING THAT WILL PERSIST FOR A FEW MORE HOURS...MAINLY AT KINT/KGSO/KFAY/KRDU...BEFORE LIFTING ABOVE 3000 FT WITH HEATING. IN ADDITION...A CLUSTER OR TWO OF SHOWERS/STORMS WILL DEVELOP NORTH INTO CENTRAL NC THROUGH EARLY AFTERNOON...BEFORE WEAKENING WITH LOSS OF HEATING THIS EVENING. A FEW SHOWERS ARE APT TO LINGER INTO THE OVERNIGHT OWING TO THE APPROACH AND PASSAGE OF A COUPLE OF DISTURBANCES ALOFT. CONFIDENCE OF TIMING AND LOCATION OF CONVECTION AT ANY PARTICULAR TERMINAL IS LOW - RELATIVELY TYPICAL FOR THIS TIME OF YEAR. - BUT WITH A RELATIVE HIGHEST PROBABILITY OF OCCURRENCE AT KFAY...WHERE A TEMPO GROUP FOR SHOWERS HAS BEEN INCLUDED FOR THE MIDDAY TO MID-AFTERNOON HOURS. AREAS OF IFR-MVFR STRATUS ARE APT TO REDEVELOP LATE TONIGHT-EARLY WED. OUTLOOK: A GOOD CHANCE OF AFTERNOON SHOWERS AND STORMS AREA-WIDE ON WED AND FRI...WITH LESSER CHANCES...MAINLY AT EASTERN TERMINALS...ON THU. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...MWS NEAR TERM...MWS SHORT TERM...MWS LONG TERM...NP AVIATION...MWS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
634 AM EDT TUE JUN 24 2014 .SYNOPSIS... BERMUDA HIGH PRESSURE WILL OVERSPREAD THE CAROLINAS IN THE DAYS AHEAD...ACCOMPANIED BY DEVELOPMENT OF A PIEDMONT TROUGH. THIS WILL LEAD TO TEMPERATURES RISING SEVERAL DEGREES ABOVE NORMAL FOR THE REMAINDER OF THE WEEK ALONG WITH SCATTERED THUNDERSTORMS. && .NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM TUESDAY...ADJUSTMENTS WERE NEEDED WITH THE DAYBREAK UPDATE TO SHIFT THE MENTION OF HEAVY RAINFALL TO INCLUDE MORNING HOURS. REPORTS FROM A LOCAL HAM OPERATOR INDICATE RAIN-RATES BENEATH THE HEAVIER CELLS IS OVER 2.5 INCHES PER HOUR. THUS FAR THE CELLS HAVE SHOWN A SLOW DRIFT NORTH. NO OTHER CHANGES...SOME AREAS WILL GET NOTABLE RAINFALL AMOUNTS TODAY. THE PREVIOUS MORNING DISCUSSION FOLLOWS. THE REMNANTS OF A FRONTAL BOUNDARY SOUTH OF THE AREA IS NOW LIFTING NORTHWARD ACROSS SOUTH CAROLINA EARLY THIS MORNING...AND IS DISCERNIBLE WITH SHOWERS IGNITING ALONG IT WITHIN A CORRIDOR OF ENHANCED LOW-LEVEL CONVERGENCE. THIS FEATURE WILL INFLUENCE NEAR TERM WEATHER BRINGING INCREASING POPS FROM SOUTH TO NORTH THROUGH THE COURSE OF THE DAY. THE BOUNDARY WILL INTERACT WITH SEA BREEZE CONVERGENCE WHICH MAY SHIFT CONVECTION FARTHER WEST IN THE MIDDLE AND LATE AFTERNOON. DEEPER MOISTURE IS POOLED ACROSS SC AND THIS IS WHERE THE HIGHER POPS WILL RESIDE FOR A GOOD PORTION OF THE DAY. OF CONCERN IS THE POTENTIAL FOR LOCALIZED FLOODING AS PRECIPITABLE WATERS RISE TO AROUND 2 INCHES WITH SOMEWHAT OF A SLUGGISH STORM MOTION. THIS COULD LEAD TO SEVERAL INCHES OF RAIN IN A SHORT TIME OVER CONFINED LOCATIONS. STORMS SHOULD MOVE GENERALLY SOUTH TO NORTH AROUND 10 MPH THIS AFTERNOON. MAXIMUM TEMPERATURE WILL RISE TO NEAR NORMAL LEVELS FOR LATE JUNE. AS RETURN FLOW GEARS UP...MINIMUMS INTO DAYBREAK WEDNESDAY WILL REMAIN BALMY AND SLIGHTLY ABOVE NORMAL FOR DAYBREAK JUNE 25TH. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 AM TUESDAY...BERMUDA HIGH AND WEAK MID LEVEL TROUGHING WILL KEEP THE PERIOD ACTIVE WITH THE SEA BREEZE AND PIEDMONT TROUGH BEING PROMINENT FEATURES. THE REMAINS OF A WEAK COLD FRONT MOVES INTO THE AREA LATER WED INTO THU BUT THIS FEATURE WILL BE VERY WEAK BY THE TIME IT REACHES THE AREA...LACKING ANY MID LEVEL PUSH. THE BOUNDARY MAY SERVE AS A FOCUS FOR CONVECTION...ESPECIALLY WED NIGHT AND AS A RESULT WILL CARRY MENTIONABLE POP WED INTO THU. AHEAD OF THIS FEATURE DEEP MOISTURE...PRECIPITABLE WATER VALUES WED LINGER OVER 2 INCHES ACROSS MUCH OF THE AREA...AND DIURNAL INSTABILITY WILL LEAD TO AFTERNOON CONVECTION. PROFILES DO NOT SUGGEST A SIGNIFICANT SEVERE THREAT...BUT CANNOT RULE OUT AN ISOLATED STRONG/SEVERE STORM. STORM MOTIONS AROUND 10 KT WILL INCREASE THE FLOODING POTENTIAL. PATTERN ALOFT BECOMES A LITTLE MORE PROGRESSIVE ON THU WITH MID LEVEL FLOW TURNING WESTERLY. THIS WILL CAUSE A DROP IN PRECIPITABLE WATER VALUES...THOUGH MOST OF THE AREA WILL REMAIN ABOVE CLIMO FOR LATE JUNE. MID LEVEL DRY AIR WILL AFFECT STORM COVERAGE BUT STILL THINK CHC POP IS WARRANTED. AS IS THE CASE ON WED THE SEA BREEZE AND PIEDMONT TROUGH WILL BE ACTIVE BUT STORM MOTIONS COULD BE WELL UNDER 10 MPH. ALTHOUGH DEEPER MOISTURE IS LESS THE SLOW STORM MOTIONS WILL AGAIN POSE A FLOODING THREAT. HIGHS WILL RUN ABOVE CLIMO...LOW TO MID 90S AWAY FROM THE COAST WITH LOWS IN THE LOW TO MID 70S. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 3 AM TUESDAY...PROGRESSIVE FLOW ALOFT ON FRI WILL TRANSITION TO GRADUAL RIDGING OVER THE SOUTHEAST FOR THE WEEKEND AND START OF NEXT WEEK. WEAK NATURE OF THE RIDGE LATE IN THE PERIOD LIMITS AMOUNT OF SUBSIDENCE/DRYING...IN FACT FORECAST SOUNDINGS SHOW PRECIPITABLE WATER VALUES INCREASING LATE IN THE PERIOD. VALUES WILL RANGE FROM 1.7 TO 2 INCHES FRI THROUGH MON...ABOVE CLIMO FOR THIS TIME OF YEAR. AT THE SURFACE BERMUDA HIGH WILL CONTINUE TO PUMP WARM MOIST AIR INTO THE SOUTHEAST AND UNDER THE BUILDING MID LEVEL RIDGE KEEP HIGHS IN THE 90S WITH LOWS IN THE LOW 70S. DEEP MOISTURE AND LIMITED CAPPING WILL KEEP SEA BREEZE AND PIEDMONT TROUGH ACTIVE EACH DAY. PRESENCE OF MID LEVEL RIDGE LATER IN THE PERIOD WILL LEAD TO SOME REDUCTION IN COVERAGE AND POP WILL SHOW A GENERAL DECREASING TREND THROUGH THE PERIOD. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 06Z...WITH RAIN DURING THE LATE EVENING VISIBILITIES WILL START TO COME DOWN AT LBT TO MVFR WITH THE OTHER TERMINALS AT VFR FOR NOW. HAVE MENTION OF MVFR AT OTHER TERMINALS AS LOW CLOUDS AND SHOWERS OFF THE COAST WORK THEIR WAY TO THE COAST. HIGH RESOLUTION WRF AND HRRR SHOW PRECIPITATION WORKING ONTO THE COAST OF SC AND MOVING INTO THE MYRTLES BEFORE SUNRISE AND INTO ILM AFTER SUNRISE. MODELS HAD A GOOD HANDLE ON LAST NIGHTS PRECIPITATION SO WILL PAY ATTENTION AND INTRODUCE THE PRECIPITATION. THIS IS A BIG CHANGE FROM THE 00Z TAFS AND HAVE ALSO MENTION CONVECTION ACROSS THE INLAND TERMINALS DURING THE AFTERNOON AS WELL. POPS HAVE INCREASED FROM THESE MODELS AND MOIST FLOW OFF THE OCEAN WITH A WEAK FRONTAL BOUNDRY TO OUR SOUTH AND A WEAK VORT MAX MOVING ACROSS THE REGION SHOULD ALL INTERACT TO INCREASE THE CHANCE OF PRECIPITATION ACROSS THE REGION THROUGHOUT THE EARLY MORNING HOURS AND INTO THE AFTERNOON. TERMINALS WILL BOUNCE BETWEEN VFR AND MVFR THROUGHOUT THE DAY WITH NO REAL GOOD FEEL ON WHEN THIS WILL OCCUR. WINDS WILL VEER FROM THE E TO THE SE ALONG THE COASTAL TERMINALS DURING THE MORNING WITH THE SEA BREEZE FRONT REACHING THE INLAND TERMINALS DURING THE AFTERNOON AND ENHANCING LIFT AND MOISTURE. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM TUESDAY...THERE IS A WATERSPOUT RISK MAINLY THIS MORNING OVER THE WATERS BENEATH STRONG SHOWERS. SHOWERS WILL DOT THE WATERS AS WINDS VEER TO SE AND S-SW TONIGHT. A WEAK WARM FRONT LIFTING NORTH COULD TRIP OFF A FEW TSTMS OVER THE WATERS TODAY THROUGH TONIGHT. REMEMBER THAT WINDS AS WELL AS WAVES ARE LOCALLY HIGHER IN AND NEAR TSTMS. NO ADVISORIES EXPECTED. SEAS MAINLY 2-3 FEET IN A MIX OF E-ESE WAVES 2 FT EVERY 5-6 SECONDS...AND ESE WAVES 1.5 FEET EVERY 9-10 SECONDS. THE AFTERNOON SEA BREEZE WILL PRODUCE ISOLATED GUSTS TO 20 KT INSHORE BETWEEN 3PM-6PM. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 AM TUESDAY...GRADIENT TIGHTENS WED AS PIEDMONT TROUGH STRENGTHENS AND BERMUDA HIGH CONTINUES TO BUILD IN FROM THE WEST. SPEEDS WILL BE A SOLID 15 KT WITH POTENTIAL FOR 20 KT LATER IN THE AFTERNOON. WEAK BOUNDARY MOVES TO THE COAST WED NIGHT INTO THU AND DISSIPATES. THIS WILL WEAKEN THE GRADIENT AND SPEEDS WILL DROP CLOSER TO 10 KT ON THU. SEA BREEZE WILL AGAIN DEVELOP WITH SOLID 15 KT POSSIBLE NEAR SHORE. SEAS BUILD TO 2 TO 4 FT WED INTO WED NIGHT WILL DROP BACK TO 2 TO 3 FT ON THU. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 3 AM TUESDAY...BERMUDA HIGH WILL REMAIN IN CONTROL THROUGH THE PERIOD WITH SOUTHWEST FLOW 10 TO 15 KT EACH DAY. SEAS 2 TO 3 FT WILL CONTINUE TO BE DOMINATED BY SHORT PERIOD SOUTHWEST WIND WAVE. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...MJC SHORT TERM...III LONG TERM...III AVIATION...MAC/MJC
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
939 AM CDT TUE JUN 24 2014 .UPDATE... SEE MORNING UPDATE. && .DISCUSSION... AT 13Z...A WEAK OUTFLOW BOUNDARY WAS OVER CENTRAL TEXAS AND SFC HIGH PRESSURE WAS OVER THE NORTHERN GULF COAST. 12Z CRP SOUNDINGS SHOWS PW VALUES OF 2.00 INCHES AND LCH WAS NEAR 1.80 INCHES. CONVECTIVE TEMP IS AROUND 84 AT CRP AND AROUND 88 DEGREES AT LCH. AT 850 MB...A MOIST AXIS EXTENDED FROM NORTH TO SOUTH FROM BRO TO FWD WITH 850 MB DEW PTS BETWEEN 15-17 C ACROSS SE TX. AN 850 TROUGH AXIS EXTENDED FROM SHV TO AROUND AUS. AT 700 MB...THE BEST MSTR WAS TO THE NE OF THE REGION BUT ANOTHER TROUGH AXIS EXTENDED FROM ABOUT DFW TO DRT. AT 250 MB...DIVERGENCE WAS NOTED OVER EAST TEXAS AND ALSO OVER WEST TEXAS WITH A SPEED MAX OVER SOUTH TEXAS. SINCE CONVECTIVE TEMPS ARE RELATIVELY LOW WITH THE ABUNDANCE OF MID LEVEL BOUNDARIES AND EXPECTED UPPER LEVEL DIVERGENCE...FEEL CONVECTION WILL INCREASE RATHER QUICKLY THIS MORNING INTO THIS AFTN. RAISED POPS TO LIKELY OVER THE CENTRAL ZONES AND HIGH END CHANCE ELSEWHERE. THE RAP AND ARW ALSO SUPPORT WIDESPREAD COVERAGE LATER TODAY. CLOUDS AND RAIN COOLED AIR WILL WREAK HAVOC WITH MAX TEMPS BUT WILL MAINTAIN CURRENT FCST VALUES FOR NOW. NEW ZONES OUT BY 1000 AM. 43 && .PREV DISCUSSION... /ISSUED 648 AM CDT TUE JUN 24 2014/ DISCUSSION... UPDATED AVIATION DISCUSSION. AVIATION... RADAR SHOWING A COUPLE AREAS OF CONVECTION THIS MORNING...WITH ONE CLUSTER OF STORMS JUST SOUTHEAST OF GLS...ANOTHER EAST TO WEST ORIENTED BAND OVER NORTHEAST TEXAS UP TOWARD JSO AND PSN...AND ANOTHER MCS NOW MOVING THROUGH WEST TEXAS. MODEL SOUNDINGS CONTINUE TO SHOW INSTABILITY...WITH LITTLE OR NO CAPPING AS EVIDENCED BY ONGOING CONVECTION THIS EARLY IN THE MORNING. THINK WILL SEE EXPANDED COVERAGE WITH DAYTIME HEATING...WITH SHOWERS AND TSTRMS BECOMING MORE NUMEROUS AFTER NOON. FOR THIS REASON HAVE INCLUDED A TEMPO OR PROB30 GROUP MOST SITES TRYING TO PICK OUT THE MOST LIKELY WINDOW. HRRR MODEL AND 4 KM WRF ALSO SUPPORT THIS SCENARIO...ALTHOUGH THOSE MODELS ALREADY MISSING SOME OF THE POTENTIALLY IMPORTANT DETAILS...FOR EXAMPLE WEST TEXAS MCS. BASED ON WHAT HAPPENED YESTERDAY CERTAINLY CANT RULE OUT THAT FEATURE MAY MAKE IT INTO OUR FA THIS AFTERNOON AS WELL...AUGMENTING RAIN CHANCES FOR THE MID OR LATE AFTERNOON. 46 PREV DISCUSSION... /ISSUED 333 AM CDT TUE JUN 24 2014/ DISCUSSION... HGX RADAR AT 3 AM IS SHOWING NORTHWARD MORNING CONVECTION EXTENDING FROM THE MATAGORDA BAY AREA EASTWARD AND SOUTHEASTWARD OUT INTO THE GULF. EXPECT THIS ACTIVITY TO CONTINUE TO DEVELOP OVER THE GULF AND MOVE INLAND AS THE DAY PROGRESSES WHILE DAYTIME HEATING AND LOW CONVECTIVE TEMPERATURES COMBINE TO INITIATE SHOWERS AND THUNDERSTORMS FURTHER INLAND LATER THIS MORNING AND ON THROUGH THE AFTERNOON HOURS. EXPECT THIS PATTERN OF LATE NIGHT THROUGH EARLY MORNING DEVELOPMENT NEAR THE COAST/OFFSHORE THEN INLAND AS THE DAY PROGRESSES TO PERSIST FOR MUCH OF THE REMAINDER OF THE WEEK AS PRECIPITABLE WATER VALUES HOVER AROUND TWO INCHES WHILE THE AREA REMAINS UNDER THE INFLUENCE OF A MID/UPPER LEVEL WEAKNESS. THROUGH THE END OF THE DAY ON FRIDAY... THE POTENTIAL EXISTS FOR A SIGNIFICANT PORTION OF SOUTHEAST TEXAS TO RECEIVE 1/2 TO 1 INCH OF RAIN WITH THE AREA`S BEST RAIN CHANCES SETTING UP FOR WEDNESDAY AND THURSDAY. SOME SPOTS COULD SEE SOME LOCALLY HEAVY RAINFALL AMOUNTS OF 2 TO 4 INCHES...AND THIS COULD LEAD TO SOME LOCALIZED FLOODING IF IT HAPPENS IN A SHORT PERIOD OF TIME. THERE IS SOME INDICATION THAT MID/UPPER LEVEL RIDGING MIGHT TRY TO BUILD BACK INTO THE AREA DURING THE UPCOMING WEEKEND AND ON INTO THE START OF NEXT WEEK...SO WILL CONTINUE TO INDICATE LOWERING RAIN CHANCES COME SUNDAY AND MONDAY. 42 MARINE... RADAR SHOWING A FEW SHOWERS AND POSSIBLY A THUNDERSTORM STREAMING NORTHWARD OVER THE GULF COASTAL WATERS EARLY THIS MORNING AND SHOULD SEE THESE ISOLATED TO SCATTERED CELLS TODAY...WITH GREATER COVERAGE LIKELY WED AND THU. WINDS TODAY AND WEDNESDAY SHOULD REMAIN MOSTLY IN THE 10 TO 15 KNOT RANGE...BUT WILL LIKELY BUMP UP MORE 15 TO 20 KNOTS AND POSSIBLY HIGHER WED NIGHT AND THURSDAY AS ONSHORE FLOW INCREASES IN RESPONSE TO TIGHTENING PRESSURE GRADIENT. ALONG WITH THE INCREASING WINDS...EXPECT SEAS TO INCREASE IN THAT THURSDAY AND FRIDAY TIME FRAME. WITH THE INCREASING WINDS AND SEAS WOULD EXPECT AT LEAST SCEC AND POSSIBLY SCA FOR LATE IN THE WEEK. 46 PREV DISCUSSION... /ISSUED 1138 PM CDT MON JUN 23 2014/ AVIATION... 00Z GUIDANCE FROM THE GFS IS CERTAINLY PAINTING A WETTER FORECAST FOR TUESDAY. AN UPPER SPEED MAX MOVES THROUGH SOUTH TEXAS WITH A S/W TROUGH MOVING SLOWLY SOUTHEAST AND STALLING OVER CENTRAL TEXAS. PW INCREASE TO AROUND 1.7" AND K-INDEX OF 33-41 WILL BE IN PLACE IN THE MORNING ACROSS THE AREA SO HAVE MADE SOME FAIRLY AGGRESSIVE CHANGES TO THE AREA INLAND TERMINALS WITH VCSH BEGINNING AROUND 15Z AND CONTINUING THROUGH THE AFTERNOON FOLLOWED BY A PROB30 WINDOW FROM 15-20Z IN THE NORTH SHIFTING SOUTHEAST 17-22Z FOR THE METRO TERMINALS. AS MOIST AS THE GFS IS IT COULD BE PERIODS OF HEAVY RAIN/TSRA SO SOME REDUCTION IN VISBY WILL PROBABLY BE NEEDED. SPEED MAX MOVES EAST AND SHRA/TSRA SHOULD TAPER OFF BUT ANOTHER S/W CAN BE SEEN APPROACHING NEAR 00Z/WED SO CHANGES MAY BE NEEDED IF THE AIRMASS DOESN`T GET WORKED OVER. 45 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 91 74 89 75 91 / 50 30 60 20 40 HOUSTON (IAH) 91 75 89 76 90 / 60 30 60 30 60 GALVESTON (GLS) 88 81 87 81 89 / 30 40 50 40 50 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...43
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
648 AM CDT TUE JUN 24 2014 .DISCUSSION... UPDATED AVIATION DISCUSSION. && .AVIATION... RADAR SHOWING A COUPLE AREAS OF CONVECTION THIS MORNING...WITH ONE CLUSTER OF STORMS JUST SOUTHEAST OF GLS...ANOTHER EAST TO WEST ORIENTED BAND OVER NORTHEAST TEXAS UP TOWARD JSO AND PSN...AND ANOTHER MCS NOW MOVING THROUGH WEST TEXAS. MODEL SOUNDINGS CONTINUE TO SHOW INSTABILITY...WITH LITTLE OR NO CAPPING AS EVIDENCED BY ONGOING CONVECTION THIS EARLY IN THE MORNING. THINK WILL SEE EXPANDED COVERAGE WITH DAYTIME HEATING...WITH SHOWERS AND TSTRMS BECOMING MORE NUMEROUS AFTER NOON. FOR THIS REASON HAVE INCLUDED A TEMPO OR PROB30 GROUP MOST SITES TRYING TO PICK OUT THE MOST LIKELY WINDOW. HRRR MODEL AND 4 KM WRF ALSO SUPPORT THIS SCENARIO...ALTHOUGH THOSE MODELS ALREADY MISSING SOME OF THE POTENTIALLY IMPORTANT DETAILS...FOR EXAMPLE WEST TEXAS MCS. BASED ON WHAT HAPPENED YESTERDAY CERTAINLY CANT RULE OUT THAT FEATURE MAY MAKE IT INTO OUR FA THIS AFTERNOON AS WELL...AUGMENTING RAIN CHANCES FOR THE MID OR LATE AFTERNOON. 46 && .PREV DISCUSSION... /ISSUED 333 AM CDT TUE JUN 24 2014/ DISCUSSION... HGX RADAR AT 3 AM IS SHOWING NORTHWARD MORNING CONVECTION EXTENDING FROM THE MATAGORDA BAY AREA EASTWARD AND SOUTHEASTWARD OUT INTO THE GULF. EXPECT THIS ACTIVITY TO CONTINUE TO DEVELOP OVER THE GULF AND MOVE INLAND AS THE DAY PROGRESSES WHILE DAYTIME HEATING AND LOW CONVECTIVE TEMPERATURES COMBINE TO INITIATE SHOWERS AND THUNDERSTORMS FURTHER INLAND LATER THIS MORNING AND ON THROUGH THE AFTERNOON HOURS. EXPECT THIS PATTERN OF LATE NIGHT THROUGH EARLY MORNING DEVELOPMENT NEAR THE COAST/OFFSHORE THEN INLAND AS THE DAY PROGRESSES TO PERSIST FOR MUCH OF THE REMAINDER OF THE WEEK AS PRECIPITABLE WATER VALUES HOVER AROUND TWO INCHES WHILE THE AREA REMAINS UNDER THE INFLUENCE OF A MID/UPPER LEVEL WEAKNESS. THROUGH THE END OF THE DAY ON FRIDAY... THE POTENTIAL EXISTS FOR A SIGNIFICANT PORTION OF SOUTHEAST TEXAS TO RECEIVE 1/2 TO 1 INCH OF RAIN WITH THE AREA`S BEST RAIN CHANCES SETTING UP FOR WEDNESDAY AND THURSDAY. SOME SPOTS COULD SEE SOME LOCALLY HEAVY RAINFALL AMOUNTS OF 2 TO 4 INCHES...AND THIS COULD LEAD TO SOME LOCALIZED FLOODING IF IT HAPPENS IN A SHORT PERIOD OF TIME. THERE IS SOME INDICATION THAT MID/UPPER LEVEL RIDGING MIGHT TRY TO BUILD BACK INTO THE AREA DURING THE UPCOMING WEEKEND AND ON INTO THE START OF NEXT WEEK...SO WILL CONTINUE TO INDICATE LOWERING RAIN CHANCES COME SUNDAY AND MONDAY. 42 MARINE... RADAR SHOWING A FEW SHOWERS AND POSSIBLY A THUNDERSTORM STREAMING NORTHWARD OVER THE GULF COASTAL WATERS EARLY THIS MORNING AND SHOULD SEE THESE ISOLATED TO SCATTERED CELLS TODAY...WITH GREATER COVERAGE LIKELY WED AND THU. WINDS TODAY AND WEDNESDAY SHOULD REMAIN MOSTLY IN THE 10 TO 15 KNOT RANGE...BUT WILL LIKELY BUMP UP MORE 15 TO 20 KNOTS AND POSSIBLY HIGHER WED NIGHT AND THURSDAY AS ONSHORE FLOW INCREASES IN RESPONSE TO TIGHTENING PRESSURE GRADIENT. ALONG WITH THE INCREASING WINDS...EXPECT SEAS TO INCREASE IN THAT THURSDAY AND FRIDAY TIME FRAME. WITH THE INCREASING WINDS AND SEAS WOULD EXPECT AT LEAST SCEC AND POSSIBLY SCA FOR LATE IN THE WEEK. 46 PREV DISCUSSION... /ISSUED 1138 PM CDT MON JUN 23 2014/ AVIATION... 00Z GUIDANCE FROM THE GFS IS CERTAINLY PAINTING A WETTER FORECAST FOR TUESDAY. AN UPPER SPEED MAX MOVES THROUGH SOUTH TEXAS WITH A S/W TROUGH MOVING SLOWLY SOUTHEAST AND STALLING OVER CENTRAL TEXAS. PW INCREASE TO AROUND 1.7" AND K-INDEX OF 33-41 WILL BE IN PLACE IN THE MORNING ACROSS THE AREA SO HAVE MADE SOME FAIRLY AGGRESSIVE CHANGES TO THE AREA INLAND TERMINALS WITH VCSH BEGINNING AROUND 15Z AND CONTINUING THROUGH THE AFTERNOON FOLLOWED BY A PROB30 WINDOW FROM 15-20Z IN THE NORTH SHIFTING SOUTHEAST 17-22Z FOR THE METRO TERMINALS. AS MOIST AS THE GFS IS IT COULD BE PERIODS OF HEAVY RAIN/TSRA SO SOME REDUCTION IN VISBY WILL PROBABLY BE NEEDED. SPEED MAX MOVES EAST AND SHRA/TSRA SHOULD TAPER OFF BUT ANOTHER S/W CAN BE SEEN APPROACHING NEAR 00Z/WED SO CHANGES MAY BE NEEDED IF THE AIRMASS DOESN`T GET WORKED OVER. 45 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 91 74 89 75 91 / 40 30 60 20 40 HOUSTON (IAH) 91 75 89 76 90 / 40 30 60 30 60 GALVESTON (GLS) 88 81 87 81 89 / 30 40 50 40 50 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...99 AVIATION/MARINE...99
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
613 AM CDT TUE JUN 24 2014 .AVIATION... SHOWERS HAVE DEVELOPED NEAR A SURFACE BOUNDARY LOCATED BETWEEN THE DALLAS-FORT WORTH METROPLEX AND THE WACO/TEMPLE/KILLEEN AREA. THE LATEST ANALYSIS INDICATES AN AXIS OF INSTABILITY LOCATED ALONG THIS BOUNDARY WITH MLCAPE AROUND 1000 J/KG...WHICH SHOULD ALLOW FOR OCCASIONAL THUNDERSTORMS THIS MORNING. STORMS WILL LIKELY OCCUR BETWEEN THE METROPLEX AND WACO WITH CELL MOVEMENT DUE EAST...SO DIRECT IMPACT AT ANY OF THE TERMINALS APPEARS FARLY SLIM FOR THE TIME BEING. BETTER CHANCES FOR CONVECTION ARRIVE LATER THIS AFTERNOON AS A SHORTWAVE CURRENTLY OVER WEST-CENTRAL TEXAS SLOWLY WORKS ITS WAY EAST. LARGE DISCREPANCIES EXIST BETWEEN VARIOUS COMPUTER MODELS WITH REGARD TO TIMING OF CONVECTION LATER TODAY. AM LEANING CLOSE TO THE NAM12 SOLUTION FOR ONSET OF CONVECTION AT AREA TERMINALS BECAUSE IT SEAMS TO HAVE THE BEST HANDLE ON THE CURRENT FEATURES AND ASSOCIATED CONVECTION. WILL INTRODUCE VCTS AT ALL TERMINALS AROUND 22-00Z THIS EVENING AND FINE TUNE THE TIMING IN LATER FORECASTS IF IT BECOMES NECESSARY. 30 && .PREV DISCUSSION... /ISSUED 411 AM CDT TUE JUN 24 2014/ 08Z/3AM SURFACE ANALYSIS SHOWED A STATIONARY BOUNDARY IN PLACE FROM SULPHUR SPRINGS TO BURLESON TO BRECKENRIDGE. THERE WERE WEAK GRADIENTS OF BOTH TEMPERATURE AND DEW POINT ALONG THE BOUNDARY WITH COOLER VALUES LOCATED NORTH OF THE BOUNDARY. LOOKING AT THE GRADIENT OF EITHER TEMPERATURE OR DEW POINT ALONG THIS BOUNDARY IS NOT VERY IMPRESSIVE...HOWEVER...OBJECTIVE ANALYSIS INDICATES THAT THIS RESULTS IN A FAIRLY TIGHT GRADIENT OF THETA-E WITH A CHANGE OF ALMOST 8 KELVIN FROM NORTH TO SOUTH ALONG THIS BOUNDARY. AS A RESULT...THINK THAT THIS BOUNDARY WILL HANG AROUND THROUGH AT LEAST THE MORNING HOURS OF THE DAY TODAY. IT MAY HOLD SOME IDENTITY INTO THE AFTERNOON HOURS AS WELL IF SHORT RANGE MODEL GUIDANCE IS ACCURATE. THE 07Z RAP INDICATED THAT THIS BOUNDARY EXTENDS UP TO THE 850 MB LEVEL WHERE THE THETA-E GRADIENT IS EVEN MORE PRONOUNCED...SHOWING A THETA-E CHANGE OF 12-16 KELVIN ALONG THE BOUNDARY THROUGH THIS MORNING. THE MAIN POINT OF THIS ANALYSIS IS THAT THIS BOUNDARY APPEARS AS THROUGH IT IS STRONG ENOUGH TO REMAIN SOMEWHERE IN THE CWA AS WE APPROACH THE PEAK HEATING HOURS OF THE DAY. IF IT STILL EXISTS THIS AFTERNOON...IT COULD BE A BIG PLAYER IN THUNDERSTORM INITIATION TODAY. REGARDING THUNDERSTORM CHANCES FOR TODAY...ALMOST ALL GUIDANCE INDICATES THAT THIS BOUNDARY IS IMPORTANT FOR THUNDERSTORM CHANCES TODAY AS MOST GUIDANCE ADVERTISES QPF ALONG THIS BOUNDARY SOMETIME THIS MORNING THROUGH THIS AFTERNOON. THE TIMING OF WHEN THIS QPF SHOWS UP IS THE KEY DIFFERENCE AMONGST THE MODELS. MANY OF THE HIGH-RESOLUTION MODELS SHOW QPF OR SIMULATED REFLECTIVITY DEVELOPING ALONG THIS BOUNDARY JUST AFTER SUNRISE THIS MORNING. IF THIS OCCURS...THE CONVECTION THAT IS INITIATED WILL PROBABLY BE RELATIVELY WEAK IN NATURE AND MAY BE SOMEWHAT ELEVATED AS MOSTLY CLEAR SKIES TONIGHT OVER THE BOUNDARY HAS ALLOWED A NICE NOCTURNAL INVERSION TO SET UP OVER THE AREA. IT`S HARD TO SAY WHETHER THIS CONVECTION WOULD BE ENOUGH TO IMPACT THE BOUNDARY OR NOT IF IT DEVELOPS THIS MORNING. IF NOTHING ELSE...IT WILL ADD CLOUDS OVER THE WARMER SIDE OF THE BOUNDARY ALLOWING DIFFERENTIAL HEATING TO REDUCE THE IDENTITY OF THE BOUNDARY BY WARMING THE COOL SIDE AND KEEPING THE WARM SIDE SHIELDED FROM SUNSHINE/HEATING. IT`S PROBABLY FOR THIS REASON THAT MOST HIGH RESOLUTION GUIDANCE MEMBERS HAVE MORNING CONVECTION ALONG AND SOUTH OF THIS BOUNDARY WITH LITTLE TO NO ADDITIONAL PRECIPITATION THIS AFTERNOON. IF THERE IS LITTLE TO NO ACTIVITY ALONG THE BOUNDARY THIS MORNING...THIS BOUNDARY PROBABLY HAS A BETTER CHANCE AT INITIATING STRONG THUNDERSTORMS ACROSS NORTH OR CENTRAL TEXAS THIS AFTERNOON. HIGH RESOLUTION GUIDANCE IS USUALLY FAIRLY RELIABLE WHEN CONSISTENTLY SHOWING A SIMULATED REFLECTIVITY SIGNAL OF THUNDERSTORM INITIATION ALONG A COMMON BOUNDARY AROUND A COMMON TIME. THEREFORE...THERE MAY BE A SLIGHTLY BETTER CHANCE THAT STORMS DEVELOP ALONG THE BOUNDARY THIS MORNING RATHER THAN HOLDING OFF UNTIL THIS AFTERNOON. THE ONLY REASON TO DOUBT SOME OF THE MODELS SHOWING THIS MORNING CONVECTION IS THE LACK OF RESPONSE IN THE REST OF THE MASS FIELDS WHERE THE QPF IS LOCATED. THAT IS...SOME POSITIVE QPF SHOWS UP SOUTH OF THE BOUNDARY...THIS SEEMS TO MAKE SENSE...HOWEVER THERE IS NO INCREASE IN MID-LEVEL RELATIVE HUMIDITY AND NO LOW-LEVEL RESPONSE IN THE WIND FIELDS. BRINGING MODEL LOGIC INTO THE REAL WORLD...THAT`S LIKE SAYING...WE`RE GOING TO HAVE RAIN...BUT NO CLOUDS. IT DOESN`T MAKE SENSE. AS A RESULT...IT IS POSSIBLE THAT THE MODELS ARE SIMPLY PUTTING QPF OUT THERE BECAUSE THERE`S A BOUNDARY AND WE HAVE SOME MOISTURE AND CAPE IN PLACE SOUTH OF THE BOUNDARY. FOR MODELS THAT DO NOT SHOW MUCH ACTIVITY ALONG THE BOUNDARY THIS MORNING...THOSE SOLUTIONS REALLY RAMP UP THE CAPE AND MOISTURE POOLING SOUTH OF THIS BOUNDARY THIS AFTERNOON. THOSE MODELS INDICATE LOWER TO MID-70S DEW POINTS POOLING UP JUST SOUTH OF THE DFW AREA THIS AFTERNOON...RESULTING IN OVER 4000 J/KG OF CAPE. GRANTED...THERE IS VERY WEAK WIND SHEAR...SO EVEN IF STORMS DEVELOP IN THIS ENVIRONMENT THEY PROBABLY WILL NOT BE VERY ORGANIZED. THAT SAID...ANY STORMS THAT DEVELOP WITH 4000 J/KG OF CAPE WILL GET BIG...FAST. LOCALLY HEAVY RAINFALL AND MICROBURSTS WOULD BE THE PRIMARY HAZARDS IF THIS SCENARIO PANS OUT. ALSO...IF THUNDERSTORMS DO NOT DEVELOP THIS MORNING...THE BOUNDARY WILL PROBABLY MOVE A BIT WITH THE WESTERN PART OF THE BOUNDARY MOVING NORTH. IN THIS SCENARIO THE BOUNDARY WILL BE LOCATED NEAR A BOWIE TO GRAPEVINE TO EMORY LINE BEFORE THUNDERSTORMS ARE MOST LIKELY TO DEVELOP. WITH WATER VAPOR SATELLITE IMAGERY SHOWING A COUPLE OF WEAK SHORTWAVE TROUGHS OVER COLORADO AND NEW MEXICO EARLY THIS MORNING...WENT AHEAD AND BUMPED UP POPS A BIT FOR THIS AFTERNOON JUST IN CASE THIS SCENARIO PANS OUT. THIS FORECAST PROBLEM SHOULD AT LEAST BE FAIRLY EASY TO FIGURE OUT TODAY...IF WE END UP WITH SCATTERED STORMS ALONG THE BOUNDARY THAT PERSIST FOR AT LEAST A FEW HOURS THIS MORNING...WE HAVE A BETTER CHANCE AT WASHING OUT OUR BOUNDARY...MAKING AFTERNOON THUNDERSTORM CHANCES LESS LIKELY. IF THERE IS BRIEF OR NO THUNDERSTORM ACTIVITY ALONG THE BOUNDARY THIS MORNING...WE COULD SEE SOME SCATTERED STRONG STORMS DEVELOP ACROSS MUCH OF NORTH AND CENTRAL TEXAS THIS AFTERNOON. HAVE POPS IN THE 20 TO 50 PERCENT RANGE TODAY DUE TO UNCERTAINTY WITH REGARDS TO HOW TODAY WILL PLAY OUT. BY LATE THIS AFTERNOON...MOST MODELS HAVE THIS BOUNDARY GETTING WASHED OUT BY PERSISTENT SOUTHERLY FLOW AND STRONG DAYTIME HEATING. FOR TONIGHT...IF WE GET A LARGE CLUSTER OF STORMS TO PERSIST THIS AFTERNOON...WE COULD SEE SOME OF THIS ACTIVITY CONTINUE ACROSS THE CWA THROUGH THE OVERNIGHT HOURS. ANY LINGERING SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE MUCH WEAKER THAN THIS AFTERNOON. OTHERWISE...IF NOTHING GETS GOING THIS AFTERNOON...OUR ATTENTION THEN TURNS TO THE HIGH PLAINS WHERE HIGH RESOLUTION MODELS CONSISTENTLY SHOW A SQUALL LINE ORGANIZING LATE TONIGHT. IF THE SQUALL LINE BECOMES STRONG ENOUGH...IT WILL CREATE ITS OWN MINI- WEATHER SYSTEM THAT COULD PROPAGATE IT SOUTHEAST OVER NORTH TEXAS BY EARLY WEDNESDAY MORNING. CONFIDENCE IN THIS IS NOT AS GREAT AS IT WAS FOR YESTERDAY MORNING...MAINLY BECAUSE LOW-LEVEL SHEAR IS SOMEWHAT LACKING IN MOST MODEL SOLUTIONS. LOW-LEVEL WIND SHEAR IS ONE OF THE KEY FACTORS THAT HELPS BALANCE COLD-POOL STRENGTH AND REALLY HELPS LINEAR CONVECTIVE SYSTEMS BECOME ORGANIZED INTO THEIR OWN MINI-WEATHER SYSTEM. IN THE ABSENCE OF STRONGER LOW-LEVEL SHEAR...THESE STORM COMPLEXES STILL BECOME QUITE STRONG WHERE THEY ORIGINATE...BUT TEND TO LOSE THEIR COLD POOLS AND DISSIPATE WHEN THEY BEGIN TO PROPAGATE AWAY FROM THE HIGH PLAINS. BECAUSE OF THE LACK OF BETTER LOW-LEVEL SHEAR...ONLY WENT WITH 30 POPS FOR THIS POSSIBILITY FOR THE FAR NORTHWESTERN CWA EARLY WEDNESDAY MORNING. WEDNESDAY...MODELS ARE FAIRLY CONSISTENT IN BRINGING A SHORTWAVE TROUGH SOUTH ACROSS THE RED RIVER TOMORROW AFTERNOON. ASSUMING THIS PANS OUT...EXPECT SCATTERED THUNDERSTORMS TO DEVELOP NORTH OF INTERSTATE 20 TOMORROW AFTERNOON AND THEN MOVE SOUTHEAST IN THE WEAK NORTHWEST FLOW ALOFT. ALSO...MODELS ARE SHOWING A FAIRLY CONSISTENT SIGNAL OF A STRONGER THAN NORMAL SEA-BREEZE BOUNDARY MOVING NORTH FROM THE GULF COAST TOMORROW. AT LEAST THAT`S WHAT IT LOOKS LIKE IN THE MID-LEVEL RELATIVE HUMIDITY FIELDS. AT ANY RATE...WITH THE CONSISTENCY OF MODELS SHOWING QPF...WITH CLOUDS...MOVING IN FROM THE GULF COAST TOMORROW AFTERNOON...WENT AHEAD AND KEPT SOME HIGHER POPS OVER THE SOUTHEASTERN CWA. THURSDAY...MODELS CONTINUE TO SHOW THAT THE WEDNESDAY SHORTWAVE TROUGH WILL SORT OF MEANDER SOUTH AND JUST BECOME A GENERAL WEAKNESS ALOFT STUCK IN BETWEEN UPPER LEVEL RIDGES TO OUR WEST AND EAST. MODELS ARE SHOWING THAT THE WESTERN RIDGE WILL BEGIN TO AMPLIFY A BIT THURSDAY AFTERNOON...POSSIBLY SPREADING SOME FORCING FOR SUBSIDENCE OVER THE FAR WESTERN CWA. AS A RESULT...KEPT HIGHEST POP CHANCES FOR THURSDAY ALONG AND EAST OF INTERSTATE 35 AS THIS IS FURTHER REMOVED FROM THE RIDGE AND STILL WELL WITHIN THE MODEL CONSENSUS LOCATION OF THE COL/UPPER LEVEL WEAKNESS AREA. WE WILL STILL HAVE PLENTY OF MOISTURE WITH LITTLE CAP IN PLACE FOR AFTERNOON THUNDERSTORM CHANCES EAST OF INTERSTATE 35...SO KEPT POPS IN THE 30-40 PERCENT RANGE AT THIS TIME. FRIDAY THROUGH EARLY NEXT WEEK...THE GFS CONTINUES TO SHOW THAT A STRONG WEST COAST UPPER TROUGH WILL MOVE EASTWARDS OVER THE ROCKIES BY FRIDAY AFTERNOON. THE GFS HAS BEEN SHOWING THIS RESULTING IN LAYING THE NORTHERN MEXICO UPPER RIDGE OVER NORTH TEXAS BY FRIDAY...AND HOLDING IN PLACE THROUGH THE UPCOMING WEEKEND. THERE ARE STILL SOME MODEL SOLUTIONS THAT INDICATE THAT UPPER LEVEL RIDGING WILL STAY WEST RESULTING IN A PERSISTENT WEAKNESS ALOFT OVER PARTS OF THE AREA THIS WEEKEND...HOWEVER THE GFS HAS BEEN EXTREMELY CONSISTENT WITH THIS SOLUTION...AND AS RESULT WAS RELIED UPON HEAVILY IN THIS FORECAST. THE GFS HAS UPPER LEVEL RIDING IN PLACE OVER NORTH TEXAS FROM FRIDAY THROUGH THE MIDDLE OF NEXT WEEK...WITH RIDGING ONLY INCREASING IN INTENSITY EARLY NEXT WEEK. WENT WITH A DRY FORECAST FOR THE ENTIRE CWA DURING THIS PERIOD AS A RESULT. ALSO WENT AHEAD AND GRADUALLY RAISED TEMPERATURES THROUGH THIS PERIOD. IF THIS VERIFIES...WE MAY GET INTO OUR FIRST 100 DEGREE HIGHS HERE BY TUESDAY OR WEDNESDAY OF NEXT WEEK. THAT`S A LONG WAYS OUT OF COURSE...BUT THE PATTERN LOOKS HOT AND DRY FOR NOW. CAVANAUGH && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 92 75 93 75 91 / 40 30 40 20 30 WACO, TX 88 73 90 73 92 / 50 30 50 20 30 PARIS, TX 91 72 90 72 89 / 30 20 40 20 40 DENTON, TX 91 73 91 73 91 / 30 30 40 20 30 MCKINNEY, TX 92 74 92 74 91 / 30 30 40 20 40 DALLAS, TX 92 75 92 74 91 / 40 30 40 20 40 TERRELL, TX 93 76 93 76 92 / 50 30 30 20 40 CORSICANA, TX 89 73 90 73 91 / 50 30 50 20 40 TEMPLE, TX 90 72 90 73 90 / 40 30 50 20 30 MINERAL WELLS, TX 89 72 90 71 90 / 50 40 30 20 20 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 30/69
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
754 AM EDT TUE JUN 24 2014 .SYNOPSIS... A WEAK AREA OF HIGH PRESSURE OFF THE COAST OF NEW ENGLAND WILL CONTINUE TO DRIFT EAST TODAY AS LOW PRESSURE ADVANCES EAST OUT OF THE MIDWEST. SOUTHERLY FLOW BETWEEN THE SYSTEMS WILL PULL IN INCREASINGLY MOIST AIR BACK INTO THE MID APPALACHIAN AND MID ATLANTIC REGION...MAINTAINING THE THREAT FOR MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS...ESPECIALLY IN THE MOUNTAINS. A COOL FRONT WILL APPROACH THE AREA FROM THE WEST ON WEDNESDAY... FURTHER INCREASING THE THREAT FOR SHOWERS AND THUNDERSTORMS OVER THE ENTIRE REGION. && .NEAR TERM /THROUGH TONIGHT/... AS OF 745 AM EDT TUESDAY... INCREASED POPS SOME ACROSS THE SOUTHEAST PIEDMONT AREAS AND INTO THE NEW RIVER VALLEY/SE WV PER LATEST HRRR AND RADAR TRENDS OF PERSISTENT -SHRA DEVELOPING FROM NEAR KDAN TO NEAR KBLF. MERGED THESE INCREASED POPS INTO EXISTING POPS AROUND 18Z. NO TSRA MENTIONED UNTIL LATE MORNING/EARLY AFTERNOON. AS OF 310 AM EDT TUESDAY... LOW LEVEL WINDS ACROSS THE BLACKSBURG FORECAST AREA WILL CONTINUE TO SLOWLY VEER INTO THE SOUTH TODAY AS HIGH PRESSURE DRIFTS AWAY FROM THE NEW ENGLAND COAST AND AS LOW PRESSURE ADVANCES EAST OUT OF THE MISSISSIPPI VALLEY. INCREASING WARM MOIST ADVECTION EXPECTED TO FINALLY OVERCOME ANY LINGERING WEDGE...WHICH SHOULD BE DISPLACED MAINLY EAST OF THE AREA BY THIS AFTERNOON. THETA E AXIS WILL REMAIN FOCUSED OVER THE WESTERN MOUNTAINS INTO TONIGHT...WITH WEAK STEERING WINDS FROM THE SOUTH FAVORING ANOTHER DAY WHERE ANY DIURNALLY DRIVEN SHOWERS/THUNDERSTORMS WITHIN AN UNCAPPED ENVIRONMENT SHOULD BE CONFINED MOSTLY TO THE MOUNTAINS...WITH ONLY A VERY LOW THREAT EAST ACROSS THE PIEDMONT WHICH WILL REMAIN CLOSER TO THE DEPARTING SURFACE RIDGE/WEDGE. AS HAS BEEN THE CASE DURING THE PAST SEVERAL DAYS...MID LEVEL LAPSE RATES AND STEERING WINDS/SHEAR REMAIN ANEMIC AND WEAK...RESPECTIVELY...IMPLYING NEGLIGIBLE SEVERE WEATHER THREAT. HOWEVER...INCREASING PRECIPITABLE WATER... ESPECIALLY OVER THE WEST...WILL HELP INCREASE RAIN EFFICIENCY IN ANY SHOWERS/STORMS THAT DRIFT NORTH THROUGH THE AREA. ALTHOUGH EXCESSIVE RAINFALL AMOUNTS CAN NOT ENTIRELY BE RULED OUT WHERE TRAINING OF CELLS (OR TOPOGRAPHICAL ANCHORING OF CELLS) OCCURS... NEGLIGIBLE DYNAMIC FORCING SHOULD LIMIT THREAT TO MORE ISOLATED IN NATURE SUCH THAT NO HEADLINE APPEARS NEEDED AT THE PRESENT TIME. TEMPERATURES TODAY AND TONIGHT SHOULD BE AT LEAST A COUPLE DEGREES WARMER THAN THOSE EXPERIENCED YESTERDAY AS WARM ADVECTION YIELDS A 24-HOUR NET INCREASE OF ABOUT 2C AT 850 MILLIBARS...BUT WILL AGAIN BE LARGELY INFLUENCED BY PERSISTENCE OF CLOUD COVER AND TIMING/ MOVEMENT OF REDEVELOPING SHOWERS/THUNDERSTORMS AND ASSOCIATED COOL OUTFLOW BOUNDARIES. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/... AS OF 430 AM EDT TUESDAY... THE PRIMARY FOCUS THROUGH THIS PERIOD WILL BE ON A HEALTHY SHORT WAVE MOVING THROUGH THE OH VALLEY TOWARD THE NE AND MID-ATLANTIC REGION. WHILE THE MAIN DYNAMICS WILL REMAIN NORTH OF THE CWA ACROSS OH/NORTHERN WV/PA...THIS SYSTEM WILL DRAG A RELATIVELY POTENT LATE JUNE COLD FRONT THROUGH THE REGION WED/WED NIGHT. MODELS IN GOOD AGREEMENT ON PATTERN THROUGH THESE PERIODS. THE MAIN CONCERN WILL BE POTENTIAL FOR STRONG TO SEVERE THUNDERSTORMS AND HEAVY RAIN. INSTABILITY IS QUITE IMPRESSIVE...BUT THIS IS PREDICATED ON FULL SUNSHINE. WITH THE POTENTIAL FOR ABUNDANT EARLY MORNING CLOUD COVER AND SHOWERS...DAYTIME INSOLATION IS IN QUESTION...ESPECIALLY WEST OF THE BLUE RIDGE. EAST OF THE BLUE RIDGE...BETTER HEATING CAN BE EXPECTED AND THUS BETTER THUNDERSTORM POTENTIAL. GIVEN THIS CONSIDERATION...FEEL THAT MODEL INSTABILITY WITH CAPES OF 2000-3000 J/KG AND LIS TO -4 ARE LIKELY OVERDONE. IN ADDITION...WITH THE MAIN DYNAMICS TRACKING WELL NORTH OF THE CWA...INDICATED SHEAR IS NIL. WITH CONDITIONS AT LEAST ONE TO TWO NOTCHES ABOVE A NORMAL PULSE TYPE THUNDERSTORM ENVIRONMENT GIVEN THE UPPER-LEVEL SUPPORT...THE THREAT FOR A FEW STRONG TO SEVERE PULSE THUNDERSTORMS CANNOT BE RULED OUT...ALBEIT SPC DOES NOT CURRENTLY HAVE EVEN A 5 PERCENT RISK ACROSS OUR REGION...FOCUSING MORE ON THE OH/PA REGION. QPF POTENTIAL SIMILAR...MAINLY FOCUSED NORTH OF THE REGION. FEEL THAT WINDS ALOFT ARE STRONG ENOUGH TO KEEP THE ACTIVITY MOVING ALONG. HOWEVER...WITH PWS OVER 100 PERCENT OF NORMAL...LOCALLY HEAVY RAIN WILL BE POSSIBLE WITH THE STRONGER STORMS. GIVEN THE GENERALLY LACK OF RAINFALL IN MOST AREAS RECENTLY...THIS SHOULD NOT BE A SIGNIFICANT PROBLEM. FOR THU...MODELS NOW PAINTING A MUCH CLEARER PICTURE OF THE AFOREMENTIONED COLD FRONT PUSHING FAR ENOUGH SOUTH OF THE REGION TO GREATLY LIMIT...PERHAPS EVEN END THE SHRA/TSRA CHANCES FOR MUCH OF THE REGION. THE EXCEPTION COULD BE NW FLOW UPSLOPE THROUGH THE ALLEGHANYS AND ESPECIALLY IN FAR SW VA/NW NC MOUNTAINS NEAREST THE STALLING FRONTAL BOUNDARY. HAVE RETAINED LOW POPS IN THESE AREAS...BUT HAVE NOW ADVERTISED UNMENTIONABLE POPS FOR THE PIEDMONT AND MOST AREAS EAST OF THE ALLEGHANY FRONT. FOR FRI...SHOULD SEE MOISTURE STARTING TO CREEP BACK TO THE EAST...ALTHOUGH AREAS EAST OF THE BLUE RIDGE SHOULD MANAGE TO HOLD ONTO ONE MORE MOSTLY SHRA/TSRA FREE DAY. HIGH CHANCE POPS WILL SPREAD BACK INTO SW VA/NW NC AND EVEN SE WV...ESPECIALLY WEST OF I-77. SHOULD SEE SLIGHTLY COOLER TEMPERATURES AND DRIER AIR FOR THU AND IN THE EAST FRI. OTHERWISE...WED AND MUCH OF THE PERIOD WEST OF I-77 WILL CONTINUE TO SEE WARM/HUMID CONDITIONS THROUGH THE PERIOD WITH MAX TEMPS NEAR TO SLIGHTLY ABOVE NORMAL AND MIN TEMPS ABOVE NORMAL. && .LONG TERM /SATURDAY THROUGH MONDAY/... AS OF 430 AM EDT TUESDAY... THERE ARE SOME FAIRLY SUBSTANTIAL DIFFERENCES ADVERTISED AMONG THE GFS AND ECMWF GOING INTO THE WEEKEND AND EARLY NEXT WEEK. WHILE THE OVERALL THEME IS FOR A BUILDING SUBTROPICAL RIDGE WITH INCREASING HEIGHTS AND TEMPS ALOFT...E.G. 588-590DM AT 500MB AND 850MB TEMPS RISING INTO THE +20C RANGE...THE ECMWF IS SUBSTANTIALLY WARMER AND DRIER THAN THE GFS. THE GFS ESSENTIALLY ADVERTISES A QUASI-STATIONARY BAROCLINIC ZONE OVER THE REGION FROM NW TO SE WITH A SERIES OF WAVES RIDING ALONG THE FRONT AND CHANCE TO GOOD CHANCE DIURNAL TSRA ACTIVITY. THE ECMWF ADVERTISES A MUCH STRONGER RIDGE...SUBSIDENCE...AND SHOVES THE BAROCLINIC ZONE WELL TO THE NE OF THE REGION. FEEL THAT THE REALITY IS LIKELY SOMEWHERE IN BETWEEN. THUS...HAVE MADE LITTLE CHANGE TO THE ALREADY ADVERTISED DAILY DIURNAL CONVECTION. MAX/MIN TEMPS WILL BE SLIGHTLY ABOVE NORMAL THROUGH THE PERIOD...ESPECIALLY MIN TEMPS...BUT IF THE ECMWF ENDS UP BEING MORE ACCURATE WITH +22C 850MB TEMPS OPPOSED TO THE GFS +17C TEMPS DURING THE SAME TIME FRAME...WE COULD START TO SEE MORE 90S CREEPING INTO THE CWA...ALONG WITH HEAT INDICES CREEPING CLOSE TO 100 IN SOME AREAS WHERE DEWPOINTS NEAR 70./TEMPS STAY ABOVE NORMAL AT NIGHT DUE TO THE MOISTURE CONTENT IN THE ATMOSPHERE...WHILE DAYTIME HIGHS STAY CLOSER TO WHAT WE EXPECT FOR LATE JUNE...WITH UPPER 70S HIGHER TERRAIN...LOWER TO MID 80S REST OF THE MOUNTAINS...AND MID 80S/NEAR 90 SOUTHEAST. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 745 AM EDT TUESDAY... WEAK WEDGE AND RESULTANT LOW-LEVEL CONVERGENCE/UPSLOPE ALONG THE BLUE RIDGE WILL CONTINUE TO SUPPORT EXTENSIVE/WIDESPREAD LOW CLOUDS...ESPECIALLY EAST OF THE ALLEGHANY FRONT THIS MORNING. MEANWHILE...FOCUS LATER IN THE DAY WILL BE ON UPSTREAM SHORT WAVE AND FRONT TO COMBINE WITH INCREASING MOISTURE TO BRING SCT-NMRS SHRA/TSRA BACK TO THE CWA. THINKING FOR TODAY IS THAT MOST OF THIS ACTIVITY WILL BE FOCUSED WEST OF THE BLUE RIDGE WHERE BETTER DYNAMICS AND INSTABILITY WILL EXIST...WITH A SLIGHTLY MORE STABLE AIR MASS EAST OF THE BLUE RIDGE. NET RESULT WILL BE WIDESPREAD MVFR CIGS THROUGH MID/LATE MORNING...IMPROVING TO LOW END VFR DURING THE AFTERNOON. EXPECT SHRA/TSRA TO DEVELOP WEST OF THE BLUE RIDGE AFT 18Z AND AFFECT PRINCIPALLY BLF/LWB THROUGH THE AFTERNOON...THEN CREEP CLOSER TO BCB/ROA AFT 00Z. MOSTLY VCTS AT THIS POINT...BUT ENOUGH CONFIDENCE TO INCLUDE PROB30 FOR BLF/LWB AFT 18Z. WITH THE LOW CLOUDS...FOG IS NOT AN ISSUE THIS MORNING. EXPECT MORE WIDESPREAD PCPN TO SPREAD EAST INTO THE CWA OVERNIGHT IN ASSOCIATION WITH AFOREMENTIONED SHORT WAVE/FRONT...SO THE POTENTIAL DOES EXIST FOR OVERNIGHT SHRA AND ISOLD TSRA...ESPECIALLY WEST OF THE BLUE RIDGE. IN FACT...SOME ACTIVITY MAY LINGER THROUGHOUT THE NIGHT. THIS WILL RESULT IN WIDESPREAD MVFR CIGS AND POTENTIAL FOR MVFR VSBYS IN -SHRA/-TSRA BR...ESPECIALLY AFT 06Z. WINDS...SSE-SSW THROUGH THE PERIOD...5-10KTS...WITH SOME POTENTIAL FOR LOW END GUSTS LATE MORNING INTO THE AFTERNOON. MEDIUM CONFIDENCE IN CIGS THROUGH THE TAF VALID PERIOD. MEDIUM TO HIGH CONFIDENCE IN VSBYS THROUGH THE TAF VALID PERIOD. MEDIUM TO HIGH CONFIDENCE IN WIND SPD/DIR THROUGH THE TAF VALID PERIOD. MEDIUM CONFIDENCE IN TSRA POTENTIAL THIS AFTERNOON/TONIGHT. EXTENDED AVIATION DISCUSSION... NEXT UPPER TROUGH AND ITS ASSOCIATED COLD FRONT WILL APPROACH FROM THE WEST TUESDAY NIGHT INTO WEDNESDAY...WITH AN INCREASING THREAT FOR MORE WIDESPREAD SHOWERS AND STORMS WEDNESDAY AFTERNOON/EVENING. TIMING REMAINS A BIT IN QUESTION AS POTENTIAL EARLIER ARRIVAL COULD MEAN MORE COVERAGE IN THE EAST INCLUDING PERIODS OF MVFR/IFR IN STRONGER STORMS...WHILE BETTER CHANCE OF MORE WIDESPREAD LOWER CONDITIONS ACROSS THE ENTIRE REGION IF THE FRONT SLOWS. MAY SEE SOME IMPROVEMENT ON THURSDAY AS THE FRONT WASHES OUT OVERHEAD OR PUSHES TO THE SE...BUT STILL ENOUGH MOISTURE WITH HEATING FOR ADDED DIURNAL CONVECTION AGAIN THURSDAY AFTERNOON WITH PERIODS OF MVFR POSSIBLE. MOISTURE LIKELY RETURNS ON FRIDAY WITH A REPEAT OF MAINLY AFTERNOON/EVENING CONVECTION FRIDAY LEADING TO BRIEF PERIODS OF MVFR/IFR. THIS TREND LOOKS TO PERSIST AGAIN ON SATURDAY WITH AT LEAST ISOLATED CONVECTION MAKING FOR OCNL MVFR/IFR IN SPOTS SATURDAY AFTERNOON AND EVENING. OTRW AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE NIGHT/EARLY MORNING...PARTICULARLY IN AREAS THAT SEE RAIN THE PREVIOUS AFTERNOON. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...WERT NEAR TERM...WERT/RAB SHORT TERM...RAB LONG TERM...RAB/WP AVIATION...JH/RAB/WERT
AREA FORECAST DISCUSSION
NWS TUCSON AZ
915 AM MST TUE JUN 24 2014 .SYNOPSIS...GENERALLY DRY CONDITIONS THROUGH THE WEEKEND. DAYTIME TEMPERATURES WILL BE NEAR TO A FEW DEGREES ABOVE AVERAGE THIS WEEK FOLLOWED BY HOTTER TEMPERATURES BY EARLY NEXT WEEK. SOME MOISTURE INCREASE IS EXPECTED TO BEGIN EARLY NEXT WEEK. && .DISCUSSION...SUNNY SKIES AT THIS TIME WITH ONLY A FEW THIN CIRRUS CLOUDS MOVING ACROSS SE AZ. DEWPOINTS AT LOWER ELEVATIONS VALID 16Z RANGED FROM THE UPPER TEENS AND 20S F NORTH TO WEST OF TUCSON...TO THE LOWER 50S F ACROSS FAR SERN SECTIONS. THESE TEMPS WERE NEARLY UNCHANGED ACROSS NRN SECTIONS VERSUS 24 HOURS AGO...BUT WERE ABOUT 10-20 DEGS F HIGHER FROM TUCSON SOUTHWARD VERSUS THIS TIME MON. SURFACE TEMPS VALID 16Z WERE NEARLY IDENTICAL TO 24 HOURS AGO. 24/12Z KTWC SOUNDING TOTAL PRECIP WATER VALUE WAS NEAR 0.30 INCH...A MUCH DRIER PROFILE VERSUS THIS TIME MON. 24 HOUR TEMP CHANGE PLOT YIELDED MINIMAL CHANGE IN THE SURFACE-600 MB LAYER...AND ABOUT 2-5 DEGS C OF WARMING ABOVE 600 MB. 24/12Z UPPER AIR PLOTS INDICATED HIGH PRESSURE CENTERED WEST OF NRN BAJA CALIFORNIA NEAR 28N/129W... AND RIDGE AXIS EXTENDED SEWD INTO SRN CHIHUAHUA. LIGHT TO MODERATE WLY/NWLY FLOW ALOFT PREVAILED OVER SE AZ. AM SOMEWHAT CONCERNED ABOUT THE POTENTIAL FOR DRY LIGHTNING ACROSS FAR SERN SECTIONS LATER TODAY...GIVEN THE ONGOING ENHANCED DEWPOINTS AS NOTED IN THE AFOREMENTIONED DIAGNOSTICS. 24/12Z NAM/GFS AND 24/13Z RUC HRRR DEPICT PRECIP ECHOES AND QPF/S TO BE EAST TO SOUTH OF THIS FORECAST AREA. THUS...FORECAST CONFIDENCE IS HIGH THAT DRY CONDITIONS WILL PREVAIL TODAY...WITH SOME CIRRIFORM CLOUDS TO MOVE ACROSS THE AREA. THERE IS ENOUGH LOWER AND MID-LEVEL MOISTURE FOR SOME CUMULOFORM CLOUDS TO OCCUR...ESPECIALLY SE OF TUCSON. THE UPPER HIGH WILL REMAIN QUASI-STATIONARY INTO WED AS AN UPPER TROUGH MOVES EWD INTO THE PACIFIC NW. THUS...WED SHOULD BE SIMILAR TO TODAY...WITH SOME CIRRIFORM CLOUDS TO MOVE ACROSS THE AREA...AND SOME CUMULOFORM CLOUDS WED AFTERNOON ESPECIALLY EAST OF TUCSON. THE UPPER TROUGH WILL MOVE EWD ACROSS THE GREAT BASIN AND NORTHERN INTERMOUNTAIN REGION THUR. THIS TROUGH WILL CONTINUE EWD INTO THE NRN/CENTRAL ROCKIES FRI. THE MAIN IMPACT ON SE AZ FROM THIS SYSTEM WILL BE SOME BREEZINESS THUR-FRI MAINLY DURING THE AFTERNOON HOURS. A VERY DRY REGIME WILL THEN CONTINUE SAT AS HIGH PRESSURE ALOFT BEGINS TO STRENGTHEN OVER THE AREA. HIGH TEMPS TODAY-SAT WILL BE AT NORMAL VALUES OR AVERAGE JUST A FEW DEGS ABOVE SEASONAL NORMALS. THERE ARE NO CHANGES FORTHCOMING TO THE INHERITED OFFICIAL FORECAST FOR TODAY. PLEASE REFER TO THE ADDITIONAL SECTIONS FOR FURTHER DETAIL. && .AVIATION...VALID THRU 25/18Z. HIGH PRESSURE WEST OF NORTHERN BAJA CALIFORNIA WILL PROVIDE WESTERLY TO NORTHWESTERLY FLOW ALOFT THRU WEDNESDAY MORNING. THERE IS ENOUGH LOWER AND MID-LEVEL MOISTURE SE OF KTUS...AND ESPECIALLY NEAR THE KDUG TERMINAL...TO PRODUCE SCATTERED CLOUDS AT 10-15K FT AGL THIS AFTERNOON AND EARLY THIS EVENING. OTHERWISE...CLEAR SKIES OR MOSTLY CLEAR SKIES WILL PREVAIL. SURFACE WIND THIS AFTERNOON AND EARLY EVENING WILL BE SW-NW AT 12-18 KTS WITH GUSTS TO NEAR 25 KTS. OTHERWISE...SURFACE WINDS WILL BE LESS THAN 10 KTS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...DRY CONDITIONS WILL PREVAIL INTO EARLY NEXT WEEK. A TROUGH OF LOW PRESSURE MOVING NORTH OF THE AREA WILL BRING BREEZY TO LOCALLY WINDY CONDITIONS MOSTLY EAST OF TUCSON THURSDAY AFTERNOON. A FEW LOCALES EAST OF TUCSON AND PARTICULARLY IN THE SAFFORD VALLEY MAY BRIEFLY APPROACH RED FLAG CRITERIA LATE THURSDAY AFTERNOON. HOWEVER...WIDESPREAD CRITICAL FIRE WEATHER CONDITIONS ARE NOT ANTICIPATED AT THIS TIME. OTHERWISE...NORMAL DIURNAL WIND TRENDS WILL OCCUR THROUGH MUCH OF THE FORECAST PERIOD...WITH OCCASIONAL GUSTS DURING THE AFTERNOON AND EARLY EVENING HOURS DUE TO STRONG DAYTIME HEATING. && .PREV DISCUSSION...STRONG RIDGE BUILDING IN OVER THE WEEKEND INTO EARLY NEXT WEEK WITH DECENT HIGH INITIALLY CONSOLIDATING OVERHEAD SUNDAY INTO MONDAY. THE LARGER SCALE FLOW AT THAT POINT WILL STILL NOT BE FAVORABLE FOR DIRECTLY ASSISTING THE PROCESS OF IMPORTING DEEP MOISTURE...BUT THE MUCH LIGHTER AND MORE AMBIGUOUS FLOW UNDER THE HIGH WILL TEND TO ALLOW GREATER INFLUENCE FROM OUTFLOW ACTIVITY IMMEDIATELY SOUTH AND SOUTHEAST OF THE AREA. THE NUMBER OF SCENARIOS ALLOWING FOR DEEP SURGE ACTIVITY INCREASE AT THAT POINT AND ULTIMATELY WE SHOULD SEE SIGNIFICANT PROGRESS AS MONSOON INFLUENCES SPREAD INTO OUR PART OF THE STATE NEXT WEEK (ESPECIALLY AFTER MONDAY OR TUESDAY). YOU PLAY THE PERCENTAGES IN THE EXTENDED AND WE`RE STARTING TO SEE THE SCENARIOS THAT ALLOW DEEPER MOISTURE INTO THE PICTURE INCREASING...INCLUDING A MARKED INCREASE IN TROPICAL ACTIVITY SOUTH OF BAJA AND PRESSURE DIFFERENTIALS ENHANCED BY THERMAL DIFFERENTIALS. FAIRLY TYPICAL FOR THE FIRST WEEK OF JULY. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON FRANCIS PREVIOUS DISCUSSION...MEYER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1124 AM MDT TUE JUN 24 2014 .UPDATE... ISSUED AT 1124 AM MDT TUE JUN 24 2014 INSTABILITY REMAINS IN PLACE OVER NORTHEAST COLORADO TODAY...BUT WITH A LOT OF CONVECTIVE INHIBITION ALSO PRESENT. WEAK SOUTHEASTERLY WINDS ON THE EASTERN PLAINS WILL PRODUCE A WEAK DENVER CYCLONE THROUGH THE AFTERNOON HOURS. QUASI-GEOSTROPHIC DIAGNOSTICS FROM THE RAP MODEL CONTINUE TO SHOW DEEP SUBSIDENCE OVER THE NORTHEAST QUARTER OF THE STATE MOST OF THE AFTERNOON. THIS WILL HELP SUPPRESS CONVECTION THROUGH AT LEAST MID-AFTERNOON BY HOLDING THE CAPPING INVERSION IN PLACE. BY EVENING THE SUBSIDENCE WILL DIMINISH WHICH MAY ALLOW SHOWERS TO BEGIN DEVELOPING. ANY SHOWERS THAT DEVELOP ARE GOING TO BE CAPABLE OF SEVERE HAIL DUE TO THE 1000-1500 JOULES OF CAPE THAT ARE EXPECTED TO BE PRESENT. STORM PREDICTION CENTER STILL HAS NORTHEAST COLORADO UNDER SLIGHT RISK OF SEVERE WEATHER...SO THE FORECAST WILL CONTINUE TO MENTION SCATTERED THUNDERSTORMS IN THE LATE AFTERNOON AND EVENING. && .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 355 AM MDT TUE JUN 24 2014 INTERESTING BUT CHALLENGING SITUATION FOR THE PERIOD REGARDING CONVECTIVE ACTIVITY. FIRST...MANY OF THE IMPORTANT PARAMETERS ARE SIMILAR TO MONDAY. VERTICAL WIND SHEAR REMAINS SIGNIFICANT AS DOES THE INSTABILITY. PRECIPITABLE WATER VALUES ARE UP FROM 24 HOURS AGO ACCORDING TO GPS SENSORS. WEAK LOW LEVEL UPSLOPE IS PREDICTED TO CONTINUE. THIS IS ALL WELL AND GOOD AND WOULD MAKE FOR ANOTHER ACTIVE CONVECTIVE DAY BY THEMSELVES. HOWEVER...CONVECTION HAS GONE ON ALMOST THE ENTIRE NIGHT ON THE NORTHEAST PLAINS WHICH WILL KEEP THINGS COOL OUT THERE FOR MUCH OF THE DAY. THERE IS ALSO SOME STRATUS FLOATING ABOUT THE LOWER ELEVATIONS AND SOME MID LEVEL CLOUDINESS HAS BEGUN TO INCREASE EAST OF THE MOUNTAINS THE LAST COUPLE OF HOURS. THIS COULD KEEP HEATING SOMEWHAT AT BAY THROUGH MUCH OF THE MORNING. INDEED MANY OF THE MODELS HAVE A SUBSTANTIAL AMOUNT OF CIN STILL RUNNING AROUND DURING THE MID TO LATE AFTERNOON. FURTHERMORE...AS THE UPPER LEVEL SHORTWAVE RIDGE MOVES IN AND IS FORECAST TO AMPLIFY A BIT THE MODELS ARE ALL PRETTY CONSISTENT SHOWING SOME MODERATE BUT RATHER DEEP QUASIGEOSTROPHIC SUBSIDENCE SPREADING OVER MOST OF THE CWA DURING THE PEAK HEATING TIME. SOME WEAKENING OF THIS DOWNWARD MOTION AND A SIGN CHANGE TO WEAK LARGE SCALE ASCENT IS PREDICTED AFTER 00Z BY SOME OF THE MODELS. SUBSIDENCE LIKE THIS HAS BEEN KNOWN TO COMPLETELY SHUT DOWN CONVECTION IN PAST CASES. BUT WITH THE POSSIBLE SIGN CHANGE EXPECTED LATE IN THE DAY THINGS MAY SIMPLY BE DELAYED SOMEWHAT AND LINGER LONGER INTO THE EVENING. SO THINGS ARE NOT TERRIBLY CUT AND DRIED. ONE THING IS RATHER CERTAIN...IF CONVECTION CAN GET GOING THERE IS A THREAT OF SEVERE WEATHER WITH JUST ABOUT ANY STORM THAT DEVELOPS. HEAVY RAINS ARE ALSO POSSIBLE WITH STORMS THAT CAN GET GOING. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 355 AM MDT TUE JUN 24 2014 ON WEDNESDAY...THE FOCUS FOR TSTMS WILL START TO SHIFT EAST OF THE URBAN CORRIDOR. AN UPPER LEVEL RIDGE OF HIGH PRESSURE WILL MOVE OVER THE STATE WITH A DRIER WESTERLY FLOW MOVING INTO THE MOUNTAINS AND FOOTHILLS. AREAS IN AND NEAR THE HIGHER TERRAIN WILL STILL SEE A SLIGHT CHANCE OF TSTMS BUT THEY WILL BE HIGH BASED AND PRODUCE PRIMARILY GUSTY WINDS. FURTHER EAST... DRY LINE WILL LIKELY DEVELOP AND THE DRIER MID LEVEL AIR MIXES DOWN TO THE SURFACE AND SHIFTS THE MOISTURE AXIS EAST OF INTERSTATE 25. EAST OF THE LINE...HIGH PW VALUES WILL STILL EXIST WITH CAPE VALUES OVER 2000 J/KG. A FEW SEVERE STORMS POSSIBLE MAINLY ALONG AND SOUTH OF THE PALMER DIVIDE. THURSDAY INTO FRIDAY...THE RIDGE WILL SHIFT TO THE EAST WITH A DRY SOUTHWESTERLY FLOW ALOFT OVER THE CWFA. BEST CHC OF STORMS WL BE OVER THE NORTHEAST PLAINS...WITH LITTLE IF ANY TSTM ACTIVITY IN AND NEAR THE MOUNTAINS AND FOOTHILLS. ON SATURDAY AN UPPER LEVEL TROUGH WILL BRUSH ACROSS COLORADO BRING WITH IT COOLER TEMPERATURES AND A SLIGHT CHANCE OF SHOWERS AND TSTMS OVER MUCH OF THE CWFA. SUNDAY INTO MONDAY...AN UPPER LEVEL RIDGE WILL BE OVER THE DESERT SOUTHWEST. THIS WILL ALLOW FOR A DRY AND WARMER WESTERLY FLOW ALOFT TO MOVE BACK INTO THE CWFA. TEMPERATURES BOTH DAYS WILL CLIMB BACK TO AROUND 90. && .AVIATION...(FOR THE TAFS THROUGH 18Z WEDNESDAY MORNING) ISSUED AT 1124 AM MDT TUE JUN 24 2014 WILL HAVE VCTS AFTER 22Z AND THEN TEMPO -TSRA AFTER ABOUT 01Z. AFTER THE EVENING THUNDERSTORMS MOVE OUT...THE NAM HAS WINDS REMAINING OUT OF THE SOUTH...INDICATIVE OF AT LEAST MODEST DRAINAGE WINDS. WITHOUT ANY SURGE OF NORTHERLIES...DO NOT THINK WE WILL SEE ANY LOW CLOUDS TOMORROW MORNING. && .HYDROLOGY... ISSUED AT 355 AM MDT TUE JUN 24 2014 WITH PRECIPITABLE WATER VALUES APPROACHING AN INCH AT BOULDER AT 4 AM ANY CONVECTION THAT MANAGES TO GET ROLLING TODAY WILL HAVE THE POTENTIAL TO PRODUCE HEAVY RAIN. PARTS OF MORGAN AND WASHINGTON COUNTIES HAD QUITE A BIT OF RAIN MONDAY NIGHT SO SOILS THERE MAY BE GETTING CLOSE TO SATURATION WITH FURTHER RAINS HAVING THE POTENTIAL TO CAUSE PROBLEMS. MODEST STORM MOTION FROM THE WEST NORTHWEST SHOULD BE SUFFICIENT TO PRECLUDE WIDESPREAD FLASH FLOOD CONCERNS AT THIS POINT ALTHOUGH A LOW THREAT DOES EXIST. THE THREAT FOR THUNDERSTORMS PRODUCING HEAVY RAIN WILL BE CONFINED TO THE NORTHEAST PLAINS FOR WEDNESDAY AND THURSDAY. A DRIER WESTERLY FLOW ALOFT OVER THE MOUNTAINS WILL PRODUCE JUST SOME HIGH BASED SHOWER AND/OR TSTM ACTIVITY OVER THE FOOTHILLS. NO FLOODING CONCERNS SATURDAY THROUGH MONDAY. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...DANKERS SHORT TERM...ET LONG TERM...COOPER AVIATION...DANKERS HYDROLOGY...ET/COOPER
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
556 PM EDT TUE JUN 24 2014 .SYNOPSIS... HIGH PRESSURE OFFSHORE WILL CONTINUE TO WEAKEN TONIGHT. A COLD FRONT AND A LOW PRESSURE SYSTEM MOVING ALONG IT WILL APPROACH THE AREA WEDNESDAY AND MOVE THROUGH BY EARLY THURSDAY. HIGH PRESSURE WILL BUILD IN FRIDAY AND REMAIN FOR MUCH OF THE WEEKEND. ANOTHER FRONT WILL ARRIVE NEXT TUESDAY OR WEDNESDAY. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... BASED ON LATEST RADAR IMAGERY AS WELL AS RUC AND COSPA RUNS (18Z GFS AND WRF TOO), WE HAVE SCALED BACK POPS AS WE HAVE REMAINED RELATIVELY MORE STABLE OVER OUR CWA AND ONGOING DEEP FLOW TRAJECTORY OF ONGOING CONVECTION WOULD BE BY-PASSING MOST OF OUR CWA THIS EVENING. WE`LL SEE WHERE THE TRENDS GO FROM THERE FOR THE NEXT UPDATE. OTHER ADJUSTMENTS WERE TO SMOOTH CURRENT TEMP DIFFERENCES AND LOWER SKY NEAR TERM SKY COVER. FOR TONIGHT...SFC HIGH PRES WILL REMAIN WELL OFFSHORE WHILE A SFC TROF AND ASSOCD FRONTAL SYSTEM WILL GRADUALLY APPROACH FROM THE NW. THE RESULTING PRES GRADIENT WILL MAINTAIN A LIGHT SLY FLOW OVER THE AREA. THIS PLUS SW FLOW ABOVE THE SFC WILL BRING INCREASING MOIST AIR IN TO THE REGION. CLOUDINESS WILL BE INCREASING OVERNIGHT INCLUDING SOME LOW CLOUDS AND POSSIBLY SOME FOG AS WELL. ALTHOUGH THERE IS NO CLEAR-CUT FORCING FOR UVV...WE HAVE MAINTAINED A CHC OR SLGT CHC POP FOR SHRA/TSRA DEVELOPING OVERNIGHT FOR AREAS N/W OF PHL. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/... THE SFC TROF AND FRONTAL SYSTEM WILL CONTINUE SEWD INTO PA ON WED AND A SHRTWV TROF ALOFT WILL ALSO APPROACH FROM THE W AND SW. THE SHRTWV WILL ENHANCE UVV...ALTHO THE BEST FORCING SEEMS TO BE TO OUR N AND NW. EVEN SO THERE WILL BE A VERY MOIST AIR MASS IN PLACE WITH PWS FCST TO BE OVER 2 INCHES. IN SPITE OF INCREASING CLOUDS...THERE SHOULD BE ENOUGH HEATING TO PRODUCE INSTBY FOR TSTMS TO DEVELOP DURING THE DAY WITH POPS INCREASING WEST TO EAST. THESE THUNDERSTORMS WILL LIKELY BE EFFICIENT RAIN PRODUCERS AND SOME LOCATIONS WILL RECEIVE HEAVY RAINFALL. STORMS WILL BE MOVING SW TO NE AND IF TRAINING OCCURS THERE COULD BE LOCALIZED FLASH FLOODING. HOWEVER ATTM WE BELIEVE THE FLOODING THREAT IS NOT WIDESPREAD OR ORGANIZED ENOUGH TO JUSTIFY A FF WATCH. WE WILL CONTINUE TO MONITOR THE SITN. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... A WEAK MEAN H5 TROUGH WILL BE ACROSS THE NORTHEAST AND NORTHERN MIDDLE ATLANTIC REGION DURING THE BEGINNING OF THE EXTENDED PERIOD. THE TROUGH GETS KICKED TO THE EAST SATURDAY ALLOWING H5 RIDGING TO TAKE PLACE ACROSS OUR PART OF THE COUNTRY. THIS RIDGING PERSISTS INTO THE BEGINNING OF NEXT WEEK. THERE ARE SIGNS BEYOND THE LONG TERM THAT THE RIDGE WILL FLATTEN ALLOWING THE WESTERLIES ALOFT TO COME CLOSE TO OUR AREA. TEMPERATURES WILL BE NEAR NORMAL FROM THU INTO SAT...THEN READINGS WILL CLIMB TO ABOVE NORMAL LEVELS NEXT WEEK. HIGH TEMPERATURES WILL BE IN THE MID/UPPER 80S MON AND APPROACH 90 (OR EXCEED IN THE METRO AREAS) NEXT TUESDAY. PRECIPITATION CHC WILL BE TIED TO TRANSIENT SHORT WAVES AND WEAK FRONTS WHICH WILL AFFECT THE AREA. TIMING OF THESE FEATURES IS POOR AT BEST BY THE OPERATIONAL MODELS...SO THE WPC POPS WERE USED IN THE EXTENDED PERIOD. THE BEST CHC FOR PCPN ARE SAT/SUN ACROSS THE NORTH AND WRN AREAS AND AGAIN NEXT TUE...MOSTLY WRN AREAS. && .AVIATION /22Z TUESDAY THROUGH SUNDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. VFR CONDS ARE IN PLACE AT ALL OUR TAF SITES AND SHOULD REMAIN SO FOR THE REST OF THE AFTERNOON AND EVE. SMWHT GUST SLY WINDS WILL DIMINISH AROUND SUNSET BUT WINDS WILL REMAIN SLY BETWEEN 5 AND 10 KT OVERNIGHT. HOWEVER THE SLY FLOW WILL BRING INCREASING MOISTURE...AND MVFR CIGS/VSBYS ARE EXPECTED TO DEVELOP OVERNIGHT INTO WED MORNING. SOME IFR CIGS ARE POSSIBLE FOR A FEW HOURS AROUND SUNRISE. CONDS SHOULD GRADUALLY IMPROVE DURG WED MORNING AND RETURN TO VFR BY MIDDAY. SLY WINDS WILL ALSO INCREASE AGAIN BY MIDDAY. SHOWERS AND T-STORMS ARE FCST TO DEVELOP DURG THE AFTN AND THESE WILL PRODUCE LOCALLY MVFR OR IFR CONDS DUE TO HEAVY RAIN AND LOW CIGS. OUTLOOK... WED NIGHT...SCT SHOWERS AND TSTMS WITH LOCAL MVFR/IFR POSSIBLE. THU THRU SUN...MOSTLY VFR WITH ISOLATED TSTMS MAINLY DURING THE AFTERNOON AND EVENING HOURS. && .MARINE... FAIRLY QUIET CONDS ARE FORECAST TO CONTINUE OVER THE NJ/DE COASTAL WATERS AND DELAWARE BAY FOR THE NEXT 24 HOURS OR SO...OR AT LEAST NO SCA FLAGS ARE EXPECTED ATTM. SLY WINDS AND SEAS WILL BE INCREASING SOME TONIGHT AND WEDNESDAY AS A FRONTAL SYSTEM APPROACHES FROM THE NW BUT CONDS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA. SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP OVER THE WATERS WED AFTN AND BECOME MORE NUMEROUS WED EVENING AND OVERNIGHT. THESE STORMS WILL TEND TO HAVE VERY HEAVY DOWNPOURS AS WELL AS THE USUAL LIGHTNING AND LOCALLY GUSTY WINDS. OUTLOOK... SUB-SCA CONDITIONS ARE EXPECTED ON THE WATERS THROUGH THE PERIOD. TSTMS ARE POSSIBLE HOWEVER...AND LOCALLY HIGHER WINDS AND SEAS CAN BE EXPECTED AT TIMES. && .HYDROLOGY... THE POTENTIAL FOR LOCALLY VERY HEAVY RAIN WEDNESDAY AND WEDNESDAY NIGHT REMAINS WHICH COULD LEAD TO SOME LOCAL FLOODING AS THE PW VALUES ARE FORECAST TO INCREASE TO AROUND 2.00 INCHES. AS A COLD FRONT ARRIVES, THE FLOW IS GENERALLY PARALLEL TO IT WHICH INTRODUCES THE RISK FOR TRAINING CONVECTIVE CELLS. THE FORECAST SOUNDINGS INDICATE THAT CONVECTION WILL HAVE THE POTENTIAL TO BE RATHER EFFICIENT RAINFALL PRODUCERS, AND ANY TRAINING OR MULTICELL CLUSTERS WILL ENHANCE THE HEAVY RAIN/FLOODING THREAT. THE ARRIVAL OF A SURFACE LOW ALONG THE FRONT MAY ALSO ENHANCE THE LOW-LEVEL CONVERGENCE AND ALLOW FOR MORE FOCUSED DOWNPOURS. THIS LOOKS TO INITIALLY BE FOCUSED ACROSS THE WESTERN ZONES WEDNESDAY, THEN IT GRADUALLY SHIFTS EAST LATE IN THE DAY AND DURING THE EVENING. THE 1-HOUR FLASH FLOOD GUIDANCE SHOWS NORTHERN NEW JERSEY AND PORTIONS OF EASTERN PENNSYLVANIA WITH VALUES AT OR LESS THAN 2.00 INCHES. THESE SIMILAR AREAS ON THE 3-HOUR FLASH FLOOD GUIDANCE HAVE VALUES BETWEEN ABOUT 2.00 AND 2.50 INCHES. IT IS THESE LOCATIONS AND THE MORE URBANIZED SPOTS THAT ARE MORE SUSCEPTIBLE TO FLASH FLOODING. A FLASH FLOOD WATCH IS NOT BEING ISSUED ATTM DUE TO SOME QUESTION ON HOW MUCH CONVECTION DEVELOPS /AREAL COVERAGE/ AND WHERE IF BECOMES FOCUSED THE LONGEST. A MENTION HOWEVER REMAINS IN THE HAZARDOUS WEATHER OUTLOOK. && .RIP CURRENTS... THERE IS A MODERATE RISK OF RIP CURRENTS FOR NEW JERSEY THE REST OF TODAY AND TONIGHT. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...O`HARA NEAR TERM...AMC SHORT TERM...AMC LONG TERM...O`HARA AVIATION...AMC/O`HARA MARINE...AMC/O`HARA HYDROLOGY... RIP CURRENTS...
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
239 PM CDT Tue Jun 24 2014 ...Update to short term... .SHORT TERM...(This evening through Wednesday) ISSUED AT 234 PM CDT TUE JUN 24 2014 Main focus is on this afternoon and tonight. Problematic forecast because the short term convective allowing mesoscale models aren`t handling the current situation that well. The most recent RAP is starting to get a clue and looks reasonable. Convection is firing off an old outflow boundary and a minor upper level pressure perturbation. Convection is building southward with southerly winds feeding into it, so think storms will continue to increase in coverage with this associated warm air advection and eventually forward propagate. Large Hail Parameter (LHP) is lower now with a value of 4. Think this is due to fairly less steep mid level lapse rates and more marginal upper level wind shear. Anyhoo, moderate instability and lower end shear will still support the notion of severe weather across the forecast area. The most significant threat is heavy rainfall with pwats up 116% above normal per blended satellite derived products. Ramped up pops and qpf, although my pops could be raised even higher, but did not want to be too out of coordination with neighbors. Will monitor and tweak pops and wx as needed in the ESTF period. Lows tonight will be in the 60s. Highs in the 80sF tomorrow with more MCS activity likely. .LONG TERM...(Wednesday night through Tuesday) ISSUED AT 231 PM CDT TUE JUN 24 2014 For Wednesday night, a lee trough will be nearly stationary with moist upslope flow. The upper level winds are very weak, but with good instability some thunderstorms will be likely mainly north of and east of Dodge City. Have upped thunderstorms chances to around 60 percent in the I-70 area and 30 to 40 percent elsewhere. The chances for widespread severe weather looks only marginal at this time with weak upper level support. Overnight lows will be mild and in the mid to upper 60s. For Thursday, a lee trough continues with moist upslope flow and again the upper winds look weak to support any severe weather. Some thunderstorms will be lingering across mainly parts of south central Kansas. Highs will range from the low to mid 90s west towards the Colorado border, to the upper 80s east across parts of south central Kansas. For the period of Friday into next Tuesday, a strong upper level shortwave trough will be moving east into the Intermountain West and Colorado Rockies on Friday afternoon. This system then lifts northeast into the Northern Plains for the Weekend. The best chances for thunderstorms looks to be along the I-70 corridor on Saturday night into Sunday morning. The main storm track then looks to remain north of Kansas into Tuesday. Overnight lows will be mild in the upper 60s to lower 70s, with highs warming from around 90 on Friday to the mid 90s on Sunday and Monday. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) ISSUED AT 1200 PM CDT TUE JUN 24 2014 VFR through much of the pd. Main exception in local areas of +tsra, mainly for KGCK this evening. -tsra will be possible too at KDDC/KHYS. Southerly winds today becoming light and variable. && .PRELIMINARY POINT TEMPS/POPS... DDC 64 87 67 89 / 70 30 40 20 GCK 64 89 67 90 / 70 20 40 20 EHA 61 89 66 93 / 50 20 30 10 LBL 63 89 68 92 / 70 20 30 20 HYS 64 87 67 88 / 70 30 60 30 P28 67 87 68 89 / 70 40 50 40 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Sugden LONG TERM...Kruse AVIATION...Sugden
AREA FORECAST DISCUSSION...UPDATED
NWS DODGE CITY KS
232 PM CDT Tue Jun 24 2014 ...Updated for Long Term... .SHORT TERM...(Today and tonight) ISSUED AT 329 AM CDT TUE JUN 24 2014 At the time of this writing (just after 0830 UTC), a small mesoscale convective system (MCS) was slowly dissolving as it moved east-southeast across southwestern Kansas. There were other weakly organized storms across northwestern Kansas. There appeared to be a slow warming in infrared cold cloud tops associated with the western Kansas convection as we head toward the early morning hours. Water vapor and RAP analysis suggested a weak shortwave trough from southern Wyoming down into central Colorado. This feature will allow the redevelopment of the southeastern Colorado leeside low with south-southeast winds resuming by mid to late morning across portions of southwestern Kansas. Winds in the wake of this morning`s MCS will be light and one or two convergence zones will likely set up at the surface where south to southeast winds of 12 to 15 knots will converge into areas of weak or nearly calm winds over portions of west central and/or northwestern Kansas. These convergence areas at the surface will foster development of surface-based thunderstorms in the 20-22Z time frame just about anywhere across far east-central/southeast Colorado and/or western Kansas. The NAM12 shows a band of enhanced mid level flow from the west-northwest across eastern Colorado and western Kansas of 28 to 34 knots (500mb)...providing ample enough deep layer shear for supercell structures with the strongest discrete convection. Any supercell storms which develop would move almost due south given the mid level flow direction out of the west-northwest. It is unclear how long discrete thunderstorm phase will last, but back on Sunday there was a supercell storm that rolled south for 4+ hours (eastern Oklahoma Panhandle into the northeastern Texas Panhandle) before becoming absorbed by other convection and transitioning to an MCS. The CAPE/Shear profile does not look all that dissimilar from the Sunday event. Should a supercell storm form and thrive in this environment, maximum hail size of tennis balls will be possible (local research /Large Hail Parameter/ in the upper single digits also supports this maximum hail size). The thinking is that any such hail event of that size would be very isolated and probably brief with many of the hail reports being half dollar to 2-inch in diameter. We increased POPs to 60 percent and included "Heavy Rain" in the grids given the continued very moist environment and impressive QPF signals from the WRF high- resolution models...as well as the ECMWF. POPs may need to be increased further (to categorical/80+) later on today as mesoscale details emerge. .LONG TERM...(Wednesday night through Tuesday) ISSUED AT 231 PM CDT TUE JUN 24 2014 For Wednesday night, a lee trough will be nearly stationary with moist upslope flow. The upper level winds are very weak, but with good instability some thunderstorms will be likely mainly north of and east of Dodge City. Have upped thunderstorms chances to around 60 percent in the I-70 area and 30 to 40 percent elsewhere. The chances for widespread severe weather looks only marginal at this time with weak upper level support. Overnight lows will be mild and in the mid to upper 60s. For Thursday, a lee trough continues with moist upslope flow and again the upper winds look weak to support any severe weather. Some thunderstorms will be lingering across mainly parts of south central Kansas. Highs will range from the low to mid 90s west towards the Colorado border, to the upper 80s east across parts of south central Kansas. For the period of Friday into next Tuesday, a strong upper level shortwave trough will be moving east into the Intermountain West and Colorado Rockies on Friday afternoon. This system then lifts northeast into the Northern Plains for the Weekend. The best chances for thunderstorms looks to be along the I-70 corridor on Saturday night into Sunday morning. The main storm track then looks to remain north of Kansas into Tuesday. Overnight lows will be mild in the upper 60s to lower 70s, with highs warming from around 90 on Friday to the mid 90s on Sunday and Monday. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) ISSUED AT 1200 PM CDT TUE JUN 24 2014 VFR through much of the pd. Main exception in local areas of +tsra, mainly for KGCK this evening. -tsra will be possible too at KDDC/KHYS. Southerly winds today becoming light and variable. && .PRELIMINARY POINT TEMPS/POPS... DDC 64 87 67 89 / 70 30 40 20 GCK 64 89 67 90 / 70 20 40 20 EHA 61 89 66 93 / 50 20 30 10 LBL 63 89 68 92 / 70 20 30 20 HYS 64 87 67 88 / 70 30 60 30 P28 67 87 68 89 / 70 40 50 40 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Kruse AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
117 PM CDT Tue Jun 24 2014 ...Update for mesoscale discussion... .MESOSCALE DISCUSSION... ISSUED AT 111 PM CDT TUE JUN 24 2014 Monitoring near term radar trends. Convection is developing along an old outflow boundary. Dual-pol precip estimates as much as 2-4" has fallen outside the CWA across Gove county. Blended satellite pwats are around 116% of normal. The overall environment is conducive to very heavy rainfall if a storm tracks over you. Short term LHP values not so high due to weak upper level shear and marginal mid level lapse rates. Tweaking pops and wx based off short term grids. Model`s aren`t handling today very well, but have ramped up pops area wide to account for this uncertainty. && .SYNOPSIS... ISSUED AT 911 AM CDT TUE JUN 24 2014 A minor upper level wave was moving across Colorado at 12Z. This feature was the partial impetus for scattered convection across the Colorado Plains and western Kansas this morning. The KDDC pwat was 1.07" this morning, or between the 50th/75th percentile. KDDC WSR-88D was indicating returned power this morning and also in regional radar mosaic. && .SHORT TERM...(Today and tonight) ISSUED AT 329 AM CDT TUE JUN 24 2014 At the time of this writing (just after 0830 UTC), a small mesoscale convective system (MCS) was slowly dissolving as it moved east-southeast across southwestern Kansas. There were other weakly organized storms across northwestern Kansas. There appeared to be a slow warming in infrared cold cloud tops associated with the western Kansas convection as we head toward the early morning hours. Water vapor and RAP analysis suggested a weak shortwave trough from southern Wyoming down into central Colorado. This feature will allow the redevelopment of the southeastern Colorado leeside low with south-southeast winds resuming by mid to late morning across portions of southwestern Kansas. Winds in the wake of this morning`s MCS will be light and one or two convergence zones will likely set up at the surface where south to southeast winds of 12 to 15 knots will converge into areas of weak or nearly calm winds over portions of west central and/or northwestern Kansas. These convergence areas at the surface will foster development of surface-based thunderstorms in the 20-22Z time frame just about anywhere across far east-central/southeast Colorado and/or western Kansas. The NAM12 shows a band of enhanced mid level flow from the west-northwest across eastern Colorado and western Kansas of 28 to 34 knots (500mb)...providing ample enough deep layer shear for supercell structures with the strongest discrete convection. Any supercell storms which develop would move almost due south given the mid level flow direction out of the west-northwest. It is unclear how long discrete thunderstorm phase will last, but back on Sunday there was a supercell storm that rolled south for 4+ hours (eastern Oklahoma Panhandle into the northeastern Texas Panhandle) before becoming absorbed by other convection and transitioning to an MCS. The CAPE/Shear profile does not look all that dissimilar from the Sunday event. Should a supercell storm form and thrive in this environment, maximum hail size of tennis balls will be possible (local research /Large Hail Parameter/ in the upper single digits also supports this maximum hail size). The thinking is that any such hail event of that size would be very isolated and probably brief with many of the hail reports being half dollar to 2-inch in diameter. We increased POPs to 60 percent and included "Heavy Rain" in the grids given the continued very moist environment and impressive QPF signals from the WRF high- resolution models...as well as the ECMWF. POPs may need to be increased further (to categorical/80+) later on today as mesoscale details emerge. .LONG TERM...(Wednesday through Monday) ISSUED AT 326 AM CDT TUE JUN 24 2014 A weak upper level ridge is progged to move through the Rockies Wednesday, then through the Plains Thursday before exiting stage right on Friday. Meanwhile, an upper level long wave trough is expected to move into the Pacific Northwest and Intermountain West Wednesday and Thursday then into the Northern Rockies and Northern Plains Friday into this weekend. A trough of low pressure at the surface will intensify across eastern Colorado as this feature approaches bringing southerly winds to western Kansas through the weekend. An exiting MCS may bring scattered thunderstorms to south central Kansas Wednesday morning but should exit the area by noon. A slight chance of thunderstorms will be possible late Wednesday afternoon into Wednesday night, otherwise expect mostly cloudy skies. Clouds decrease in coverage Thursday with partly cloudy skies expected through Saturday. A chance of thunderstorms will then be possible across northern Kansas and the I-70 corridor Saturday night as lift increases due to an upper level shortwave moving through across Nebraska. Otherwise expect a slight increase in cloud cover. Upper level ridging looks to build into the southern Rockies by the beginning of next week. This should suppress any significant weather across western Kansas with partly cloudy skies. Highs throughout the extended period start out in the upper 80s Wednesday with lower 90s expected Thursday through the weekend. Highs in the mid to upper 90s are possible early next week. Lows start out in the upper 60s Thursday morning with lower 70s anticipated through early next week. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) ISSUED AT 1200 PM CDT TUE JUN 24 2014 VFR through much of the pd. Main exception in local areas of +tsra, mainly for KGCK this evening. -tsra will be possible too at KDDC/KHYS. Southerly winds today becoming light and variable. && .PRELIMINARY POINT TEMPS/POPS... DDC 64 87 67 88 / 70 30 40 20 GCK 64 89 67 89 / 70 20 40 20 EHA 61 89 66 92 / 50 20 30 10 LBL 63 89 68 90 / 70 20 30 20 HYS 64 87 67 88 / 70 30 60 30 P28 67 87 69 88 / 70 40 50 40 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE...Sugden SYNOPSIS...Sugden SHORT TERM...Umscheid LONG TERM...Hovorka_42 AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1236 PM CDT Tue Jun 24 2014 ...Update to aviation forecast discussion... .SHORT TERM...(Today and Tonight) Issued at 327 AM CDT TUE JUN 24 2014 Quiet weather was in place across the local forecast area early this morning with light winds, high clouds, and departing surface high pressure. Farther to the west in western KS and eastern CO, a loosely organized convective system was making slow eastward progression. This convection seemed tied to a weak upper disturbance that was making a very slow eastward progression out of CO and NM through weak flow aloft. Additional weak, but seemingly more well-defined upper waves were located over southern California and eastern Montana. While the CA wave will be slow to move east, it seems that the Montana system may dive southeast and possibly interact with the system in eastern Colorado by tonight. In terms of the local forecast and sensible weather through tonight, expect the area of showers and thunderstorms to continue with slow but steady eastward development. Generally speaking, the NMM, ARW, and HRRR seem to be handling the situation well through the day, which coincides fairly well with larger scale model guidance as well. This suggests that showers and a few storms may encroach upon the Highway 81 corridor by early afternoon and possibly build into far eastern KS by early evening. All indications suggest a tight instability gradient from east to west which also gradually progresses to the east with time. This should prevent the convection from developing more quickly east today even if a few cold pools push out from convection. As the instability does arrive, it will be rather meager, as will wind shear profiles, and even strong storms seem quite unlikely through tonight. All told, much of the area stands a good chance to see at least some precip by sunrise on Wednesday, although amounts may be spotty. Aside from precip, temperatures will be in the lower to middle 80s today, with some question in just how warm it will get depending largely on cloud cover as more widespread clouds could hold everyone in the lower 80s. Winds will be light through tonight and dewpoints will remain fairly comfortable...in the low to middle 60s. .LONG TERM...(Wednesday through Monday) Issued at 327 AM CDT TUE JUN 24 2014 A slow upper shortwave trough translates southeast over the CO Rockies and central plains on Wednesday afternoon. Position and timing from guidance was fairly similar in developing a swath of showers and thunderstorms across the CWA from the overnight into the afternoon hours. Ample southerly moisture transport is aided by PWAT values in excess of 1.6 inches through the period. Have increased chances across the area during the day, gradually tapering off west to east by Wednesday evening. Do not expect severe storms with main threat being heavy rain and flash flooding. Occasional showers and thunderstorms are expected from Thursday onward as weaker upper perturbations within the mean flow give much uncertainty where mesoscale boundaries or areas of lift are positioned for scattered convection to form. Similar to previous trends, late afternoon into early evening time frame during peak heating and minimal inhibition is likely. The weekend forecast, for the most part, appears dry Friday and Saturday with temporary ridging over the area. On Saturday, H5 flow begins to back and increase toward the southwest in response to a deepening upper trof across the western CONUS. By the late afternoon period, a moist and unstable airmass in place may trigger scattered thunderstorms along/ahead of a cold front stretched over central KS into south central NE. A few storms may be severe in proximity to the convergent boundary where surface based CAPE in excess of 3000 J/KG complements effective shear near 40 kts. Activity weakens as it progresses eastward by Sunday with some indication of redevelopment by late afternoon across east central areas. Otherwise trends from the GFS/ECMWF depict weak trofs rotating through the main wave as the frontal boundary becomes a focal point for additional scattered convection Sunday evening into Monday. Minor adjustments were made to temperatures in the extended. Insulation from cloud cover and rainfall Wednesday should hold highs to the low 80s throughout the afternoon. Sunshine returns Thursday as consensus guidance warrants increased highs in the mid and upper 80s. With ample sunshine and increased boundary layer mixing through the weekend, warming trend continues with highs in the upper 80s to low 90s by Monday. Overnight lows follow suit from the mid 60s Thursday to the low 70s Friday into Monday. && .AVIATION...(For the 18Z TAFs through 18Z Wednesday Afternoon) Issued at 1236 PM CDT TUE JUN 24 2014 Thunderstorm chances increasing over the next few hours with upper wave approaching. May see a break for much of the 03-09Z window but expect increasing trends again thereafter. Have kept VCTS going but will watch trends for anything more persistent. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Barjenbruch LONG TERM...Bowen AVIATION...65
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1200 PM CDT Tue Jun 24 2014 ...Update to aviation... .SYNOPSIS... ISSUED AT 911 AM CDT TUE JUN 24 2014 A minor upper level wave was moving across Colorado at 12Z. This feature was the partial impetus for scattered convection across the Colorado Plains and western Kansas this morning. The KDDC pwat was 1.07" this morning, or between the 50th/75th percentile. KDDC WSR-88D was indicating returned power this morning and also in regional radar mosaic. && .SHORT TERM...(Today and tonight) ISSUED AT 329 AM CDT TUE JUN 24 2014 At the time of this writing (just after 0830 UTC), a small mesoscale convective system (MCS) was slowly dissolving as it moved east-southeast across southwestern Kansas. There were other weakly organized storms across northwestern Kansas. There appeared to be a slow warming in infrared cold cloud tops associated with the western Kansas convection as we head toward the early morning hours. Water vapor and RAP analysis suggested a weak shortwave trough from southern Wyoming down into central Colorado. This feature will allow the redevelopment of the southeastern Colorado leeside low with south-southeast winds resuming by mid to late morning across portions of southwestern Kansas. Winds in the wake of this morning`s MCS will be light and one or two convergence zones will likely set up at the surface where south to southeast winds of 12 to 15 knots will converge into areas of weak or nearly calm winds over portions of west central and/or northwestern Kansas. These convergence areas at the surface will foster development of surface-based thunderstorms in the 20-22Z time frame just about anywhere across far east-central/southeast Colorado and/or western Kansas. The NAM12 shows a band of enhanced mid level flow from the west-northwest across eastern Colorado and western Kansas of 28 to 34 knots (500mb)...providing ample enough deep layer shear for supercell structures with the strongest discrete convection. Any supercell storms which develop would move almost due south given the mid level flow direction out of the west-northwest. It is unclear how long discrete thunderstorm phase will last, but back on Sunday there was a supercell storm that rolled south for 4+ hours (eastern Oklahoma Panhandle into the northeastern Texas Panhandle) before becoming absorbed by other convection and transitioning to an MCS. The CAPE/Shear profile does not look all that dissimilar from the Sunday event. Should a supercell storm form and thrive in this environment, maximum hail size of tennis balls will be possible (local research /Large Hail Parameter/ in the upper single digits also supports this maximum hail size). The thinking is that any such hail event of that size would be very isolated and probably brief with many of the hail reports being half dollar to 2-inch in diameter. We increased POPs to 60 percent and included "Heavy Rain" in the grids given the continued very moist environment and impressive QPF signals from the WRF high- resolution models...as well as the ECMWF. POPs may need to be increased further (to categorical/80+) later on today as mesoscale details emerge. .LONG TERM...(Wednesday through Monday) ISSUED AT 326 AM CDT TUE JUN 24 2014 A weak upper level ridge is progged to move through the Rockies Wednesday, then through the Plains Thursday before exiting stage right on Friday. Meanwhile, an upper level long wave trough is expected to move into the Pacific Northwest and Intermountain West Wednesday and Thursday then into the Northern Rockies and Northern Plains Friday into this weekend. A trough of low pressure at the surface will intensify across eastern Colorado as this feature approaches bringing southerly winds to western Kansas through the weekend. An exiting MCS may bring scattered thunderstorms to south central Kansas Wednesday morning but should exit the area by noon. A slight chance of thunderstorms will be possible late Wednesday afternoon into Wednesday night, otherwise expect mostly cloudy skies. Clouds decrease in coverage Thursday with partly cloudy skies expected through Saturday. A chance of thunderstorms will then be possible across northern Kansas and the I-70 corridor Saturday night as lift increases due to an upper level shortwave moving through across Nebraska. Otherwise expect a slight increase in cloud cover. Upper level ridging looks to build into the southern Rockies by the beginning of next week. This should suppress any significant weather across western Kansas with partly cloudy skies. Highs throughout the extended period start out in the upper 80s Wednesday with lower 90s expected Thursday through the weekend. Highs in the mid to upper 90s are possible early next week. Lows start out in the upper 60s Thursday morning with lower 70s anticipated through early next week. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) ISSUED AT 1200 PM CDT TUE JUN 24 2014 VFR through much of the pd. Main exception in local areas of +tsra, mainly for KGCK this evening. -tsra will be possible too at KDDC/KHYS. Southerly winds today becoming light and variable. && .PRELIMINARY POINT TEMPS/POPS... DDC 85 65 87 67 / 60 60 20 30 GCK 85 64 87 67 / 60 60 20 30 EHA 84 64 90 66 / 60 50 20 30 LBL 87 64 90 68 / 60 60 20 30 HYS 80 64 85 67 / 40 40 20 30 P28 86 68 87 69 / 40 60 30 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...Sugden SHORT TERM...Umscheid LONG TERM...Hovorka_42 AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
411 PM EDT TUE JUN 24 2014 .SYNOPSIS... HIGH PRESSURE SLOWLY SLIDES OFF THE COAST TODAY. A WEAK COLD FRONT WILL APPROACH THE REGION FROM THE NORTHWEST WEDNESDAY AND SLOWLY PUSH ACROSS THE AREA WEDNESDAY NIGHT AND THURSDAY. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... SATELLITE AND RADAR IMAGERY THIS AFTERNOON ARE CONFIRMING THAT THE COMBINATION OF DRY AIR AND MID LEVEL WARMING IS KEEPING ANY CONVECTION FROM FORMING OR MOVING INTO THE REGION AT THIS TIME. THE MODELS SHOWED THAT THIS MID LEVEL WARMING WOULD CONTINUE TO STRENGTHEN THROUGH ABOUT 3Z...THUS LIMITING AND OPPORTUNITY FOR POP UP CONVECTION THIS AFTERNOON AND THIS EVENING. SO EXPECT TO SEE A DRY EVENING. THE LOW LEVEL MOISTURE WILL BE ON THE INCREASE THIS EVENING AND DEW POINTS ARE REFLECTING THAT AS THEY HAVE BEEN SLOWLY RISING THIS AFTERNOON INTO THE MID TO UPPER 60S. THIS INCREASE IN MOISTURE WILL CONTINUE TONIGHT AS THE SOUTHERLY FLOW CONTINUES. THIS COULD LEAD SOME SHOWER DEVELOPMENT LATER TONIGHT TOWARDS MORNING AS A WEAK BOUNDARY TO THE SOUTH BEGINS TO APPROACH THE AREA AHEAD OF THE MAIN UPPER TROUGH OVER THE OHIO VALLEY. SO HAVE SLOWLY RAMPED UP TO CHANCE POPS ACROSS THE VA/NC BORDER AND SOUTHWARD TOWARD 12Z. NOT CONFIDENT TO GO HIGHER WITH THE POPS AT THIS STAGE...BUT ANY SHOWERS COULD PRODUCE A BRIEF DOWNPOUR. FOR LOWS OVERNIGHT...WITH THE ADDITIONAL MOISTURE ADVECTING IN TONIGHT WITH THE SOUTHERLY FLOW...HAVE KEPT THE LOWS UP TOWARD THE MAV NUMBERS...ALLOWING FOR SOME RADIATIONAL COOLING WITH THE CLEAR SKY EARLY TONIGHT. CLOUDS MAY ARRIVE LATER WHICH COULD PUMP READINGS UP TOWARD MORNING. THE MET NUMBERS LOOK A LITTLE TOO HIGH GIVEN THE CHANCE FOR SOME COOLING EARLY IN THE NIGHT. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... THE MODELS AGREE ON THE UPPER TROUGH SLIDING ACROSS THE OHIO VALLEY INTO PENNSYLVANIA AND THE NORTHEASTERN US WEDNESDAY EVENING INTO THURSDAY...BUT ARE STRUGGLING SOME TO DEPICT THE FEATURES AND LIFT PATTERNS SOUTH OF THE TROUGH OVER VA AND NC. SO THIS HAS LED TO SOME UNCERTAINTY WITH THE POPS FOR WED AFTERNOON INTO THURSDAY. WITH THE TROUGH LIFTING TO THE NORTH...THE BEST FORCING IS ALSO LIFTING NORTH AND SHOULD MOVE THROUGH NRN VA/WRN MD INTO PA WED AFTERNOON. THE SURFACE BOUNDARY WILL SLIDE THROUGH VA/NC DURING THIS TIME...BUT THE BOUNDARY IS WEAK AND THE LIFT IS NOT FOCUS SO HAVE HELD MOST POPS IN THE CHANCE RANGE FOR WED AFTERNOON INTO THE OVERNIGHT HOURS. DID KEEP A LITTLE AREA OF LIKELY POPS ACROSS THE NORTH...CLOSER TO THE FORCING. THE OTHER FEATURE TO WATCH IS THE MODELS SHOWING SOME SHORTWAVE ENERGY OVER THE SERN US COAST THAT GETS PULLED NORTHWARD ON WED. THIS COULD KICK OFF SHOWERS ACROSS COASTAL AREAS FROM ERN NC THROUGH THE DELMARVA. BUT AGAIN THE FORCING IS NOT STRONG AND THE TIMING IS EARLY IN THE DAY. SO FOR NOW HAVE JUST GONE WITH LOW CHANCE POPS WITH THAT WAVE. THE MODELS HAVE SPED UP THE MOVEMENT OF THE BOUNDARY SO HAVE THE SFC FRONT OFF THE COAST BY THURSDAY MORNING WITH THE UPPER TROUGH EXITING BY THURS AFTERNOON. SO HAVE SPED THE CLEARING OF THE POPS THUR AFTERNOON...WHICH COULD BE DRY EVERYWHERE BASE ON HOW QUICK THE DRY AIR ARRIVES IN THE NW FLOW ALOFT. BY THURS EVENING INTO FRIDAY...WILL SEE HIGH PRESSURE ARRIVE AND SLOWLY SLIDE OFF THE COAST NORTH OF THE AREA. THIS WILL TURN THE SFC FLOW FROM THE NORTH ON THURSDAY BACK TO THE SE BY FRI AFTERNOON. WITH THE BOUNDARY STALLING OVER THE CAROLINAS...COULD SEE SOME POP UP CONVECTION ALONG THE FRONT SO HAVE KEPT SLGT CHC POPS IN THE SOUTH BUT DID DRY OUT AREAS FURTHER TO THE NORTH. FOR TEMPERATURES...HAVE GENERALLY TRENDED NEAR THE MOS NUMBERS FOR THE PERIOD...LEANING TOWARD THE WARMER MAV NUMBERS ON WED WITH SOME MORNING SUNSHINE...AND AGAIN ON WED NIGHT WITH THE CLOUDS AND HIGHER MOISTURE THAT WILL TAKE TIME TO ERODE AFTER THE BOUNDARY CROSSES. FROM THURS TO FRIDAY...HAVE LEANED MORE TOWARD A STRAIGHT BLEND...KEEPING TEMPERATURES A BIT MILDER. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... AGREE WITH WPC THAT BOTH THE GFS AND ECMWF ARE SIMILAR WITH OVERALL PATTERN FOR THE PERIOD. THIS LOOKS TO BE A TYPICAL SUMMERTIME PATTERN FOR THE AREA. A RIDGE WILL SLOWLY BUILD ALOFT ALONG THE EAST COAST WITH HIGH PRESSURE STRENGTHENING IN THE EASTERN ATLANTIC. THIS SHOULD PROVIDE A CHANCE OF AFTERNOON OR EVENING THUNDERSTORMS AND TEMPERATURES A LITTLE ABOVE NORMAL. WITH HIGHS AROUND 90 AND LOWS NEAR 70. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... WATCHING A FEW -SHRA MOVING NORTH ACROSS THE ALBEMARLE SOUND THAT COULD IMPACT KECG MID/LATE AFTN. NOT CONFIDENT ENOUGH TO INCLUDE MENTION IN TAF ATTM. OTW...VFR CONDITIONS AND LIGHT SE WINDS EXPECTED INTO TONIGHT. MOISTURE WILL CONTINUE TO INCREASE OVERNIGHT...AND WITH LIGHT SE FLOW IN PLACE THERE IS SOME CONCERN FOR LOW STRATUS OR FOG EARLY WED MORNING OVER SE TERMINALS. WILL INCLUDE SOME MVFR VSBY (4SM) AT KECG FOR NOW...AND MONITOR TRENDS AT KORF/PHF. AN APPROACHING COLD FRONT WILL BRING LAYERED MOISTURE OVERHEAD FOR WEDNESDAY THROUGH SATURDAY. THERE WILL BE A POSSIBILITY OF MAINLY AFTN AND EVENING TSTMS...ESPECIALLY ON WEDNESDAY. AREAS OF MVFR/PATCHY IFR FOG OR STRATUS WILL BE PSBL EACH MORNING NEAR SUNRISE. && .MARINE... HIGH RESOLUTION MODELS ALL DEPICT A SOUTHERLY SURGE UP THE BAY. THIS DOES HAPPEN SOMETIMES WITH HIGH PRESSURE CENTERED OFF THE EAST COAST THIS TIME OF THE YEAR. LOOKING AT THE MODEL WINDS ONLY THE RUC SHOWS WINDS REACHING SMALL CRAFT CRITERIA. FOR NOW WILL FOLLOW THE LOCAL WRF AND KEEP WINDS AROUND 15KTS WITH SOME GUSTS TO AROUND 18 KTS. AFTER MIDNIGHT THE WINDS WILL BEGIN TO DECREASE. ALL MODELS SHOW A COLD FRONT APPROACHING THE WATERS ON WEDNESDAY AND THIS FRONT WILL CROSS THE WATERS ON WEDNESDAY NIGHT. THIS IS A FAIRLY WEAK FRONT. AFTER THE FRONT PASSES HIGH PRESSURE BUILDS IN FROM THE WEST. THE WINDS WILL INCREASE TO 10 TO 15 KTS BEHIND THE FRONT. THE HIGH WILL SLOWLY MOVE OFF THE COAST THIS WEEKEND AND GRADUALLY SHIFT THE WINDS TO THE SOUTHWEST BY NEXT WEEK. WINDS WILL STAY UNDER SMALL CRAFT CONDITIONS THROUGH THE FORECAST PERIOD. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR MDZ025. NC...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR NCZ102. VA...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR VAZ098>100. MARINE...NONE. && $$ SYNOPSIS...ESS NEAR TERM...ESS SHORT TERM...ESS LONG TERM...JAB AVIATION...JDM/LKB MARINE...JAB
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
242 PM EDT TUE JUN 24 2014 .SYNOPSIS... HIGH PRESSURE WILL EXTEND FROM THE NEW ENGLAND COAST INTO THE MID- ATLANTIC THROUGH TONIGHT. A COLD FRONT WILL CROSS THE AREA WEDNESDAY NIGHT. HIGH PRESSURE BUILDS THURSDAY...THEN SHIFTS EAST ACROSS THE AREA FRIDAY. HIGH PRESSURE OVER THE SOUTHERN STATES BRINGS AN UNSTABLE PERIOD THIS WEEKEND INTO NEXT WEEK. && .NEAR TERM /THROUGH WEDNESDAY/... SURFACE HIGH WAS LOCATED ALONG THE MID-ATLANTIC COAST EARLY THIS AFTERNOON...WITH SOUTHERLY FLOW WELL ESTABLISHED ACROSS THE CWA. 12Z KIAD RAOB INDICATED AN INCREASE IN MOISTURE /PW 1.35 INCHES/ AND EXPECT MOISTURE TO CONTINUE TO INCREASE THROUGH THE AFTERNOON AND EVENING. RADAR SHOWS THAT A FEW SHOWERS HAVE ALREADY BEGUN TO POP UP ALONG THE ALLEGHENY FRONT. OROGRAPHIC LIFT AND SOME INSTABILITY WILL CONTINUE TO SUPPORT SCATTERED SHOWER AND THUNDERSTORM DEVELOPMENT THROUGH THE AFTERNOON IN THIS AREA...BUT RELATIVE LACK OF A TRIGGER AND CAPPING WILL LIKELY PRECLUDE SUCH DEVELOPMENT MUCH FURTHER EAST PARTICULARLY ON THE LEE SIDE OF THE BLUE RIDGE. THIS THINKING IS IN LINE WITH LATEST RUNS OF THE HRRR AND WRF-ARW...AND POPS/WX THIS EVENING REFLECT THIS. THOSE STORMS THAT AFFECT THE WESTERN CWA HOWEVER COULD PRODUCE HEAVY RAINFALL...ESPECIALLY IF MULTIPLE STORMS MOVE OVER THE SAME AREA. LARGER SCALE LIFT IS FORECAST TO SPREAD THROUGH THE MID-ATLANTIC ON WEDNESDAY. MOISTURE/INSTABILITY ARE ALSO FORECAST TO BE BETTER...WITH GFS FORECASTING OVER 2" PW VALUES AND THE NAM NOT TOO FAR AWAY FROM THAT. HEAVY RAINFALL AND LOCALIZED FLASH FLOODING WILL BE A CONCERN...AND WET MICROBURSTS MAY POSE AN ISOLATED SEVERE RISK DURING THE AFTERNOON. ASSUMING SOME BREAKS IN THE CLOUD COVER EARLY IN THE DAY...LEANED TOWARD THE WARMER MAV GUIDANCE FOR MAXIMA WEDNESDAY. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... CONVECTION MAY CONTINUE WELL INTO THE EVENING AS A COLD FRONT DROPS INTO THE CWA. THIS FRONT IS FORECAST TO MOVE THROUGH LATE WEDNESDAY NIGHT INTO EARLY THURSDAY. IMPROVING CONDITIONS COMMENCE THEREAFTER AS NORTHWEST WINDS BRING LOWER PW/DEWPOINT AIR THROUGH THE CWA. THERE WILL STILL BE SOME CLOUDS AS THE UPPER TROUGH LAGS AND SOME COOLER AIR ALOFT WILL BE OVERTOP WARM AIR AT THE SURFACE /GIVEN DOWNSLOPING FLOW/. MUCH OF THE CWA WILL CONTINUE TO BE IN THE POST-FRONTAL AIR MASS ON FRIDAY. IT WILL BE RATHER WARM...BUT HUMIDITY SHOULD STILL BE LOW. EXCEPTION MAY BE ACROSS THE HIGHLANDS WHERE THE OLD BOUNDARY MAY SNAKE ITS WAY BACK TOWARD THE APPALACHIAN CHAIN. THIS MAY RESULT IN A FEW SHOWERS AND THUNDERSTORMS POPPING UP FOR THE AFTERNOON AND EVENING. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... A WAVE OF LOW PRESSURE PARKED OVER THE CAROLINAS WILL USHER ONSHORE EASTERLY LOW LEVEL FLOW INTO THE AREA FRIDAY NIGHT AND INTO SATURDAY MORNING. THIS FLOW IS LIGHT HOWEVER, SO DAYTIME HEATING SHOULD MIX OUT ANY NIGHTTIME INVERSION RATHER QUICKLY DURING THE DAY SATURDAY. UPPER LEVEL RIDGING WILL BUILD OVER THE REGION THROUGH THE BEGINNING OF NEXT WEEK. AT THE SURFACE...AGREEMENT ON THE EXACT PLACEMENT OF THE SUBTROPICAL HIGH SUNDAY THROUGH THE BEGINNING OF NEXT WEEK IS MUCH LOWER BETWEEN THE MODELS. THE GFS HAS IT STALLED OVER NEW ENGLAND WITH LOW PRESSURE STALLED OVER THE SOUTHEASTERN US...WHEREAS THE EURO RESOLVES THE HIGH TO REMAIN OFF THE SOUTHEAST COAST. THE PRIMARY DIFFERENCE BETWEEN THESE SOLUTIONS IS THAT HIGH PRESSURE OFF THE SOUTHEAST COAST WILL BRING WARMER/MORE HUMID SOUTHERLY FLOW TO THE AREA WHEREAS THE LOW LOCATED OVER NEW ENGLAND WILL BRING IN A SOUTHEAST FLOW THAT MAY SHOW A BIT MORE OF A MARITIME INFLUENCE. WITH WNW FLOW ALOFT AND GENERALLY PLENTY OF SUNSHINE DURING THE MORNING AND EARLY AFTERNOON HOURS DAILY...AFTERNOON DESTABILIZATION/CONVECTION IS POSSIBLE REGARDLESS OF THE SOLUTION THAT VERIFIES AND THE GENERAL PATTERN OF AFTERNOON CONVECTION WOULD SEEM A SAFE BET THROUGH THE PERIOD. WITH PERSISTENT SOUTH/SOUTHEASTERLY FLOW THROUGH THE LONG TERM HIGH TEMPS SHOULD STEADILY INCREASE SATURDAY THROUGH TUESDAY...WITH TUESDAYS HIGHS POSSIBLY WELL INTO THE 90S. IF THE HIGH DOES POSITION ITSELF OFF OF THE SOUTHEAST COAST THEN TWEAKING UPWARD OF THESE TEMPERATURES IS POSSIBLE AS MORE WARMER CONTINENTAL AIR WOULD BE ADVECTED IN. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... THUNDERSTORMS THAT DEVELOP SHOULD BE CONFINED WEST OF THE BLUE RIDGE THROUGH THIS EVENING. LOW PROBABILITY EXISTS FOR LOW CLOUDS DEVELOPING LATE TONIGHT FOR LCL MVFR/IFR. THEN FOCUS SHIFTS TO MORE NUMEROUS SHOWERS AND THUNDERSTORMS WEDNESDAY PARTICULARLY IN THE AFTERNOON. COLD FRONT MOVES ACROSS THE AREA WEDNESDAY NIGHT. POST-FRONTAL AIR MASS SHOULD LEAD TO DRY CONDITIONS THURSDAY INTO FRIDAY. LOW CEILINGS AND FOG COULD OCCUR IN ONSHORE FLOW THROUGH THE NIGHT AND INTO THE MORNING FRIDAY AND INTO THE MORNING SATURDAY. ADDITIONALLY...REDUCED VISIBILITY IS POSSIBLE IN AFTERNOON SHOWERS AND THUNDERSTORMS SATURDAY AND SUNDAY. && .MARINE... SOUTHERLY FLOW CONTINUES TO INCREASE THIS AFTERNOON...AND A PERIOD OF SCA WINDS UP THE BAY/LOWER TIDAL POTOMAC IS EXPECTED THROUGH THE EVENING. MARINE AREA SHOULD REMAIN THUNDERSTORM FREE THROUGH TONIGHT...BUT EXPECT THUNDERSTORMS POSSIBLY CONTAINING GUSTY WINDS TO AFFECT THE WATERS WEDNESDAY AFTERNOON INTO EVENING. COLD FRONT MOVES SOUTH OF THE WATERS WEDNESDAY NIGHT. WEAK HIGH PRESSURE BUILDS IN TO END THE WEEK. && .TIDES/COASTAL FLOODING... ANOMALIES WERE RUNNING AROUND 1 FT ABOVE NORMAL THIS AFTERNOON. WHAT REMAINS OF THE AFTERNOON HIGH TIDE IS THE LOWER OF THE NEXT TWO...AND MINOR TIDAL FLOODING IS NOT EXPECTED. HOWEVER THE OVERNIGHT/EARLY WEDNESDAY MORNING HIGH TIDE CYCLE WILL BE VULNERABLE TO MINOR TIDAL FLOODING AGAIN /LIKE LAST NIGHT/. WILL BE ISSUING A COASTAL FLOOD ADVISORY FOR ANNE ARUNDEL...BALTIMORE AND DC FOR THE LATE NIGHT/EARLY WEDNESDAY MORNING HIGH TIDE CYCLE. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...COASTAL FLOOD ADVISORY FROM 3 AM TO 9 AM EDT WEDNESDAY FOR DCZ001. MD...COASTAL FLOOD ADVISORY FROM 3 AM TO 9 AM EDT WEDNESDAY FOR MDZ011-014. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR ANZ531- 532-538>540. SMALL CRAFT ADVISORY FROM 11 AM TO 6 PM EDT WEDNESDAY FOR ANZ530>534-537>543. SMALL CRAFT ADVISORY UNTIL 2 AM EDT WEDNESDAY FOR ANZ533-534- 537-541>543. && $$ SYNOPSIS...BPP/CEB NEAR TERM...BPP SHORT TERM...BPP LONG TERM...CEB AVIATION...BPP/CEB MARINE...BPP/CEB TIDES/COASTAL FLOODING...BPP
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
124 PM EDT TUE JUN 24 2014 .AVIATION... //DISCUSSION... LARGE VARIATION IN CLOUD BASES THIS AFTERNOON OVER THE TERMINAL SITES WITH EVEN SOME BREAKS IN THE CLOUDS NOTED ON VISIBLE SAT. HOWEVER...THIS IS CONTRIBUTING TO DESTABILIZATION OF THE ATMOSPHERE...WHICH SHOULD ALLOW CLOUDS TO LOWER AGAIN AND SUPPORT SHOWER AND THUNDERSTORM ACTIVITY THIS AFTERNOON FROM FNT SOUTH. EXPECT PREVAILING CLOUD BASES IN THE MVFR/VFR RANGE...WITH QUICK DROPS IN CIG AND VISBY TO IFR IN HEAVY SHOWERS AND THUNDERSTORMS. A FEW STRONGER STORMS WITH WIND GUSTS TO 40 KNOTS CANNOT BE RULED OUT THIS AFTERNOON ESPECIALLY FROM PTK SOUTH...HOWEVER...CONFIDENCE IS LOW. PRECIP ACTIVITY SHOULD DIMINISH LATER THIS AFTERNOON INTO EARLY EVENING AS A SURFACE TROUGH PASSES. MOIST GROUND AN A SLACKENING PRESSURE GRADIENT WILL SUPPORT THE FORMATION OF LOWERING CLOUDS AND FOG AFTER SUNSET. THE PASSAGE OF A COLD FRONT WILL OCCUR GRADUALLY OVERNIGHT...SWINGING WINDS AROUND TO THE NORTHEAST AND GRADUALLY IMPROVING VISIBILITIES. FOR DTW...AN INCREASE IN SHOWER ACTIVITY WITH A FEW THUNDERSTORMS IS EXPECTED THIS AFTERNOON THROUGH AROUND 22Z. MOIST ENVIRONMENT WILL SUPPORT HEAVY RAIN AND QUICK DROPS IN CIG AND VIS TO IFR RANGE. USED TEMPO GROUP TO ACCOUNT FOR THIS. A FEW STORMS MAY CONTAIN GUSTY WINDS TO 40 KNOTS. FOG IS EXPECTED TO BUILD IN AFTER SUNSET...WITH IFR RESTRICTIONS POSSIBLE...ESPECIALLY AFTER 04Z. //DTW THRESHOLD THREATS... * HIGH CONFIDENCE IN CEILING BELOW 5000 FT TODAY AND TONIGHT. * MEDIUM CONFIDENCE IN THUNDERSTORM TIMING DURING THE AFTERNOON. && .PREV DISCUSSION...ISSUED 1158 AM EDT TUE JUN 24 2014 UPDATE... CURRENT RADAR SHOWS AN AREA OF MODERATE RAIN WITH EMBEDDED HEAVIER ELEMENTS OVER THE TRI CITIES AND NORTHERN THUMB. THIS AREA IS ASSOCIATED WITH RIGHT ENTRANCE REGION UPPER LEVEL FORCING ALONG WITH LOW LEVEL CONVERGENCE ALONG A SURFACE TROUGH. SOUTH OF THIS...PRECIP IS LESS WIDESPREAD...BUT A FEW STRONGER SEGMENTS WITH VERY HEAVY RAIN AND GUSTY WINDS TO AROUND 30 KNOTS ARE NOTED. THE WESTERN EDGE OF THE STEADIER RAIN IS PROGRESSING SLOWLY BUT STEADILY EASTWARD AS THE INDIVIDUAL ELEMENTS MOVE NORTHEAST. THIS EASTWARD SHIFT IN THE PRECIP SHIELD WILL CONTINUE AS THE UPPER TROUGH CONTINUES TO LIFT NORTHEASTWARD. UPSTREAM RADAR MOSAIC SHOWS LOTS OF BREAKS IN THE PRECIP...LEADING TO SOME DOUBT IN THE COVERAGE OF PRECIP FROM THE METRO DETROIT COUNTIES TO THE OHIO BORDER THIS AFTERNOON. EXPECT THIS TO FILL IN SOMEWHAT THIS AFTERNOON...BUT THE BEST UPPER FORCING AND LOW LEVEL CONVERGENCE LOOKS TO FAVOR THE AREA NORTH OF METRO DETROIT AND SOUTH OF THE TRI CITIES...WHICH HAS THE GREATEST THREAT FOR HEAVY RAINFALL. STILL...GIVEN THE VERY MOIST ATMOSPHERE...CATEGORICAL POPS EVERYWHERE LOOK GOOD. MAIN HAZARD THIS AFTERNOON/EVENING WILL BE LOCALLY HEAVY RAINFALL...WITH SOME LOCALIZED FLOODING WITH TRAINING STORMS. CAN NOT RULE OUT A FEW STRONGER STORMS WITH GUSTY WINDS MAINLY FROM METRO DETROIT TO THE OHIO BORDER...BUT OVERALL LACK OF INSTABILITY WILL LIMIT THE THREAT. EXPECT PRECIP COVERAGE TO BEGIN A DOWNWARD TREND OVER THE TRI-CITIES BY MIDAFTERNOON. PREV DISCUSSION...ISSUED 403 AM EDT TUE JUN 24 2014 SHORT TERM... TODAY AND TONIGHT COMPARED TO YESTERDAY...THE LARGER SCALE WEATHER FEATURES HAVE BECOME MORE ORGANIZED IF NOT STRONGER IN MAGNITUDE. THE RESULT WILL BE A WET DAY AROUND SE MICHIGAN. EXPECT SHOWERS AND THUNDERSTORMS TO BECOME WIDESPREAD DURING THE MORNING AND LAST THROUGH EARLY EVENING BEFORE DRIFTING EASTWARD OUT OF THE AREA. THE REST OF TONIGHT WILL BE CONCERNED WITH THE PROGRESS OF A TRAILING COLD FRONT THAT WILL MOVE THROUGH THE OHIO BORDER BY SUNRISE WEDNESDAY. SATELLITE IMAGERY AND MODEL ANALYSIS FIELDS INDICATE A WELL-DEFINED UPPER LEVEL TROUGH MOVING THROUGH THE MIDWEST AND MISSISSIPPI VALLEY DURING THE EARLY MORNING. THERE IS ALSO A DISTINCT JET MAX OVER THE GREAT LAKES WHERE THE TROUGH IS PHASING WITH THE NORTHERN STREAM CANADIAN TROUGH/LOW. THE ENTRANCE REGION OF THIS JET IS SETTING UP TO SUPPORT ENHANCED LIFT ALONG AND EAST OF THE TROUGH AXIS FROM THE MID MISSISSIPPI VALLEY INTO THE SOUTHERN GREAT LAKES. THESE UPPER LEVEL FEATURES ARE WELL-ALIGNED WITH THE SURFACE TROUGH AND LOW TO MID LEVEL MOISTURE AXIS CONSISTING OF 850 MB DEWPOINT AROUND 13C, 700 MB DEWPOINT AROUND 5C, AND PRECIPITABLE WATER APPROACHING 2 INCHES. THE RESULT IS A BROAD AREA OF SHOWERS AND THUNDERSTORMS FROM ARKANSAS INTO SOUTHERN LAKE MICHIGAN AT PRESS TIME WHICH WILL EXPAND NORTHEASTWARD THROUGH THE REST OF LOWER MICHIGAN DURING THE MORNING AND PERSIST THROUGH THE AFTERNOON. THE 00Z MODELS COLLECTIVELY HAVE A GOOD HANDLE ON THE BULK MASS AND MOISTURE FIELDS...BUT THE NAM AND RECENT RUNS OF THE RAP ARE MORE THAN A SERVICEABLE REPRESENTATION OF THE SW-NE ORIENTED BAND OF CONVECTION SETTING UP PARALLEL TO THE UPPER FLOW. FORECAST SOUNDINGS FROM THE NAM THROUGH BUFKIT ANALYSIS INDICATE MBE VECTORS ALIGNED WITH THE MEAN FLOW...WHICH IS A HEAVY RAINFALL SIGNATURE...BUT HIGH-RES RUNS OF THE HRRR AND WRF-NMM ARE MORE PROGRESSIVE AS IS THE LARGER SCALE PATTERN IN THE GFS AND ECMWF. THIS IS ENOUGH EVIDENCE TO HOLD OFF ON FLOOD HEADLINES FOR NOW BUT PLAN TO HIGHLIGHT HEAVY RAINFALL IN THE FORECAST WITH THE EXPECTATION OF 1-2 INCH TOTALS AND LOCALLY HIGHER AMOUNTS THROUGH THE DAY...MAINLY OVER THE SOUTH HALF OF SE MICHIGAN. THE SOUTHERN STREAM UPPER TROUGH WILL SLIDE EASTWARD TONIGHT AND TAKE THE RAIN SHIELD OUT OF SE MICHIGAN BY MID EVENING. THAT WILL LEAVE THE NORTHERN STREAM UPPER TROUGH/LOW TO PIVOT SOUTHWARD DURING THE REST OF THE NIGHT. SUBSIDENCE IN BETWEEN THESE TWO FEATURES WILL HELP DRY THINGS OUT FROM A RAINFALL PERSPECTIVE BUT BOUNDARY LAYER MOISTURE WILL REMAIN HIGH WITH WEAK GRADIENT FLOW SUPPORTING BOTH LOW CLOUDS AND FOG DURING THE OVERNIGHT HOURS. THE ASSOCIATED COLD FRONT WILL BRING A WIND SHIFT TO THE NORTHEAST IN THE SAGINAW VALLEY SHORTLY AFTER MIDNIGHT WHICH WILL PROGRESS SOUTHWARD DURING THE NIGHT BUT LOW LEVEL DRY ADVECTION WILL BE SLOW UNTIL AFTER SUNRISE. LONG TERM...WEDNESDAY THROUGH SUNDAY THE PSEUDO ZONAL UPPER LEVEL JET AXIS WILL BE IN THE PROCESS OF EXITING THE REGION ON WEDNESDAY. SOME FAIRLY BIG CHANGES IN THE MODEL GUIDANCE COMPARED TO 24 HOURS AGO. NWP IS NOW MORE UNIFORM/LESS NOISY IN BRINGING THE UPPER LEVEL DISTURBANCE OVER THE DAKOTAS DIRECTLY INTO LOWER MICHIGAN FOR THE AFTERNOON. IN ADDITION...ANOTHER FAVORABLE ZONE OF RIGHT ENTRANCE REGION DYNAMICS ARE EXPECTED TO SET UP SHOP OVER SOUTHEASTERN MICHIGAN WITH JET ENERGY THAT IS ASSOCIATED WITH THE AFOREMENTIONED UPPER LEVEL VORTICITY MAXIMUM. THIS CONCURRENT FORCING SHOULD ALWAYS GIVE ONE PAUSE AND CERTAINLY DOES HERE TOO. THE PROBLEM IS THE FORECASTED THERMODYNAMIC PROFILE IS EXPECTED TO BE STABLE WITH A SUBSIDENCE INVERSION CENTERED BETWEEN 700-600MB. THERE IS THE POTENTIAL TO BYPASS THIS FEATURE...WHICH WILL REQUIRE A HIGH AMOUNT OF BOUNDARY LAYER MOISTURE. NAM IS SUPPORTIVE OF THIS...BUT WITH IT/S HIGH BIAS IT/S NOT EXACTLY A STRONG ENDORSEMENT. WILL CONTINUE TO GO DRY HERE...AS THIS LOOKS LIKE A CALL FOR THE SHORT TERM. HIGH TEMPERATURES ARE EXPECTED TO RANGE IN THE 70S NORTH...TO NEAR 80 FOR THE HIGH SFC PRESSURE AREAS SOUTH AND EAST OF THE GLACIAL RIDGE. STRONG MID TO UPPER LEVEL GEOPOTENTIAL HEIGHT RISES WILL THEN LEAD TO STRONG SURFACE HIGH PRESSURE FOR THE END OF THE WEEK. NWP SIGNAL IN THE MODEL OUTPUT SUGGESTS THERE WILL ALSO BE A HEAVY COMPONENT FROM THE STABLE LAKE AGGREGATE. DRY WEATHER WITH A MODERATING AIRMASS SHOULD LEAD TO VERY FAVORABLE WEATHER CONDITIONS. AN EASTERLY FLOW TRAJECTORY SEEMS TO BE PLAYING SOME HAVOC WITH FORECASTED SFC TEMPERATURES...BUT READINGS SHOULD PUSH 80 DEGREES THURSDAY AND EXCEED 80 DEGREES BY FRIDAY. MARINE... ACTIVE STRETCH OF WEATHER WILL PERSIST INTO MID WEEK FOR THE EASTERN GREAT LAKES AS A PAIR OF FRONTS WORK THROUGH THE AREA. THE FIRST FRONT IS DRAPED ALONG A LINE FROM LAKE ONTARIO AND LAKE ERIE...SOUTHWEST INTO THE OHIO VALLEY AND WILL PRODUCE SHOWERS AND THUNDERSTORMS THROUGH THIS AFTERNOON. THIS WILL VEER WINDS FROM SOUTHERLY TO WESTERLY. A SECOND COLD FRONT WILL DROP SOUTHWARD OUT OF CANADA THROUGH THE CENTRAL GREAT LAKES TONIGHT WEDNESDAY...USHERING MODEST NORTHERLY WINDS DOWN THROUGH LAKE HURON. A WEAK PRESSURE GRADIENT WILL KEEP WINDS LIGHT THROUGH THE PERIOD...GENERALLY LESS THAN 15 KNOTS...WHICH IN TURN WILL KEEP WAVE HEIGHTS IN CHECK. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....DT UPDATE.......DT SHORT TERM...BT LONG TERM....CB MARINE.......CB YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS HASTINGS NE
107 PM CDT TUE JUN 24 2014 .UPDATE... ISSUED AT 1100 AM CDT TUE JUN 24 2014 PROBABLY ONE OF THE BEST WAYS TO DESCRIBE SHORT-TERM FORECASTING IN THIS FICKLE...ACTIVE SUMMER PATTERN IS "FORECASTING-BY- NOWCASTING." ALTHOUGH CONFIDENCE IS REASONABLY HIGH THAT THE MAJORITY OF THE CWA WILL SEE AT LEAST A LIGHT SHOWER/BRIEF THUNDERSTORM DURING THE NEXT 12-18 HOURS...CONFIDENCE IN TIMING/PLACEMENT IS EVER-CHANGING AS MOST MODELS ARE STRUGGLING MIGHTILY WITH THE DETAILS...WITH SOME DEPICTING MORE GOING ON THAN ACTUALLY IS...AND OTHERS NOT ENOUGH. IN REALITY...THERE ARE ESSENTIALLY 3 SEPARATE AREAS OF SHOWERS/STORMS WITHIN OR VERY NEAR THE EDGES OF THE CWA RIGHT NOW...BUT NOT CURRENTLY AFFECTING THE MAJORITY OF THE AREA. AS A RESULT...HAVE KEPT POPS BELOW LIKELY RANGE EXCEPT FOR WHERE RADAR/SATELLITE TRENDS SUGGEST RAIN SHOULD ACTUALLY OCCUR WITHIN THE NEXT 2-3 HOURS...WHICH AS OF THIS WRITING IS PRIMARILY THE DEPARTING MAINLY LIGHT SHOWER ACTIVITY WITHIN THAYER/FILLMORE COUNTIES...AND ALSO THE SMALL CLUSTER OF SHOWERS/ISOLATED STORMS SLIDING INTO THE VALLEY COUNTY AREA. OTHER ISOLATED CONVECTION IS SKIRTING THE FAR SOUTHERN CWA IN KS...WHILE MEANWHILE THE MAJORITY OF THE CWA IS CURRENTLY IN WHAT COULD BE A MULTIPLE-HOUR BREAK FROM SHOWERS/STORMS...ALTHOUGH THAT IS NO GUARANTEE EITHER SO HAVE AT LEAST KEPT MODEST 20-30 POPS GOING IN ALL AREAS THROUGH THE REST OF THE DAY...WITH HIGHER 40S-50S CONCENTRATED IN THE WEST. AS HAS BEEN THE CASE LATELY...THIS IS A WEAKLY-FORCED BUT WEAKLY CAPPED PATTERN OF WEST-NORTHWEST FLOW ALOFT...WITH HOURLY MESOANALYSIS CURRENTLY SUGGESTING TWO SUBTLE SHORTWAVE TROUGHS...ONE CENTERED OVER CENTRAL NEB AND THE OTHER SLIDING THROUGH NORTHERN KS. THESE WAVES ARE INDUCING MODEST THETA-E/MOISTURE ADVECTION WITHIN THE 850-700 MILLIBAR LEVEL...WHICH IS THE MAIN DRIVING FORCE BEHIND THE THUS-FAR ELEVATED ACTIVITY TODAY. AGREE WITH THE STORM PREDICTION CENTER THAT THE MAIN SEVERE WEATHER THREAT SHOULD STAY AT LEAST A FEW COUNTIES WEST OF THE CWA TODAY OVER THE HIGH PLAINS WHERE MID LEVEL LAPSE RATES ARE STEEPER AND MIXED LAYER-CAPE IS MORE FAVORED TO AVERAGE 1000+ J/KG BY MID-LATE AFTERNOON INTO THIS EVENING...BUT EVEN SO...CANNOT COMPLETELY RULE OUT THE RISK OF A STRONG TO MARGINALLY SEVERE STORM LOCALLY EITHER...ESPECIALLY SOUTHWEST OF A LEXINGTON-OSBORNE LINE. AS FOR OTHER FORECAST ELEMENTS TODAY...UNLIKE YESTERDAY WE ARE PROBABLY NOT LOOKING AT A WELL-DEFINED/MULTI-HOUR PERIOD OF CLEARING AS SKIES SHOULD CONTINUE TO AVERAGE PARTLY-MOSTLY CLOUDY AS NEW CONVECTION DEVELOPS UPSTREAM. AS A RESULT...WOULD NOT BE SURPRISED TO SEE SOME PLACES HELD DOWN IN THE LOW-MID 70S FOR HIGHS TODAY. ALTHOUGH DID NOT GO QUITE THIS LOW JUST YET...DID SHAVE ROUGHLY 2-3 DEGREES OFF PREVIOUS HIGHS IN MOST AREAS TO GET THE BALL ROLLING THAT DIRECTION...CALLING FOR THE MAJORITY OF THE CWA TO TOP OUT NO HIGHER THAN UPPER 70S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 405 AM CDT TUE JUN 24 2014 MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND TEMPERATURES. CURRENT SURFACE ANALYSIS HAS A RIDGE OF HIGH PRESSURE ACROSS THE AREA EARLY THIS MORNING. SURROUNDING RADARS SHOW SHOWERS AND THUNDERSTORMS ON THE HIGH PLAINS GRADUALLY MOVING TOWARDS THE EAST. THE SURFACE HIGH IS EXPECTED TO MOVE OFF TO THE EAST. AN UPPER LEVEL WAVE IS EXPECTED TO MOVE INTO THE AREA DURING THE DAY. EXPECT THE CURRENT PRECIPITATION TO CONTINUE TO MOVE TO THE EAST AND INTO THE AREA BY DAYLIGHT. THE THUNDERSTORMS WILL CONTINUE TO MOVE ACROSS THE AREA DURING THE MORNING HOURS AND INTO THE AFTERNOON. THE HRRR AND THE 4KM WRF BOTH HAVE THE MAIN BAND OF THUNDERSTORMS MAINLY THROUGH THE FORECAST AREA BY MID AFTERNOON. THE MAIN DIFFERENCE IS THAT THE HRRR BRINGS IN ANOTHER BAND LATER THIS AFTERNOON. HAVE KEPT CHANCES IN DURING THE LATE AFTERNOON AND INTO THE NIGHT TIME HOURS. SEVERAL TIMES LATELY THERE HAVE BEEN MORE THUNDERSTORMS THAT DEVELOP ON THE HIGH PLAINS DURING THE AFTERNOON. THE THUNDERSTORMS MOVE INTO THE FORECAST AREA LATE EVENING AND OVERNIGHT. THE MUCAPE IS BEST DURING THE AFTERNOON BUT A LITTLE REMAINS THROUGH THE NIGHT. EXPECT THERE COULD BE A STRONG STORM OR TWO AROUND THE AREA THIS AFTERNOON AND EVENING...THEN TURN INTO A RAIN EVENT DURING THE NIGHT TIME HOURS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 405 AM CDT TUE JUN 24 2014 THE BIGGEST CHALLENGE WILL BE DETERMINING CHANCES OF RAIN IN THE LONG TERM. THE ZONAL FLOW WILL GRADUALLY BECOME MORE SOUTHWEST AS AN UPPER LEVEL TROUGH MOVES INTO THE WESTERN UNITED STATE. THIS WILL HELP KICK UP PULSES OF ENERGY INTO THE HIGH/GREAT PLAINS THAT WILL GIVE US A SHOT A SHOWER/THUNDERSTORMS FOR MOST PERIODS OF THE LONG TERM. THE GREATEST CHANCE OF RAIN WILL BE FRIDAY NIGHT AS A WARM FRONT MOVES IN AND THROUGH THE AREA...ALONG WITH AN INCREASED LOW- LEVEL JET AND POTENTIAL STRONG CONVERGENCE NEAR THE NOSE OF THE JET NEARBY. STRONG TO SEVERE STORMS CAN NOT BE RULED OUT...JUDGING BY SEVERE PARAMETERS...FOR MUCH OF THE LONG TERM...BUT NARROWING DOWN A DAY THAT IT WOULD BE MORE LIKELY IS TOO DIFFICULT TO IDENTIFY NOW. TEMPERATURES APPEARED TO BE PRETTY MUCH ON TRACK FROM THE PREVIOUS FORECAST...SO NO MAJOR CHANGES TO TEMPERATURES. && .AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z WEDNESDAY) ISSUED AT 107 PM CDT TUE JUN 24 2014 ASIDE FROM ANY POSSIBLE THUNDERSTORM ACTIVITY...CONFIDENCE IS FAIRLY HIGH IN VFR CEILING/VISIBILITY THROUGH THE NEXT 24 HOURS. THE MILLION DOLLAR QUESTION...AS HAS BEEN FOR DAYS NOW...IS THE LIKELIHOOD/EXTENT OF ANY POSSIBLE SHOWERS/STORMS IMPACTING THE TERMINALS. FOR NOW...THE ONLY MENTION OF ANY THUNDERSTORM POSSIBILITY AT EITHER SITE HAS BEEN CONFINED TO THE INITIAL 3-7 HOURS OF THE PERIOD THIS AFTERNOON/EARLY EVENING...AND EVEN THEN HAVE ONLY WENT WITH A GENERIC VICINITY THUNDERSTORM (VCTS) MENTION DUE TO LOW CONFIDENCE IN COVERAGE. HAVE STARTED VCTS A BIT SOONER AT KGRI GIVEN THE PRESENCE OF AN ONGOING STRONG STORM ONLY ABOUT 20 MILES NORTH OF THE TERMINAL...ALTHOUGH THIS STORM COULD VERY WELL REMAIN OFF TO THE NORTH. CANNOT COMPLETELY RULE OUT ADDITIONAL THUNDERSTORM ACTIVITY DURING THE LATTER 12-17 HOURS OF THE PERIOD...BUT CONFIDENCE IS NOT EVEN HIGH ENOUGH FOR VCTS AT THIS POINT. SURFACE WINDS WILL NOT BE MUCH OF AN ISSUE...AGAIN ASIDE FROM ANY THUNDERSTORM-RELATED ENHANCEMENTS...AS SUSTAINED WINDS THROUGH THE PERIOD ARE EXPECTED TO AVERAGE UNDER 10KT...GENERALLY FROM SOME SOME TYPE OF SOUTHERLY DIRECTION BUT ALSO PRONE TO SOME VARIABLENESS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...PFANNKUCH SHORT TERM...JCB LONG TERM...HEINLEIN AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1101 AM CDT TUE JUN 24 2014 .UPDATE... ISSUED AT 1100 AM CDT TUE JUN 24 2014 PROBABLY ONE OF THE BEST WAYS TO DESCRIBE SHORT-TERM FORECASTING IN THIS FICKLE...ACTIVE SUMMER PATTERN IS "FORECASTING-BY- NOWCASTING." ALTHOUGH CONFIDENCE IS REASONABLY HIGH THAT THE MAJORITY OF THE CWA WILL SEE AT LEAST A LIGHT SHOWER/BRIEF THUNDERSTORM DURING THE NEXT 12-18 HOURS...CONFIDENCE IN TIMING/PLACEMENT IS EVER-CHANGING AS MOST MODELS ARE STRUGGLING MIGHTILY WITH THE DETAILS...WITH SOME DEPICTING MORE GOING ON THAN ACTUALLY IS...AND OTHERS NOT ENOUGH. IN REALITY...THERE ARE ESSENTIALLY 3 SEPARATE AREAS OF SHOWERS/STORMS WITHIN OR VERY NEAR THE EDGES OF THE CWA RIGHT NOW...BUT NOT CURRENTLY AFFECTING THE MAJORITY OF THE AREA. AS A RESULT...HAVE KEPT POPS BELOW LIKELY RANGE EXCEPT FOR WHERE RADAR/SATELLITE TRENDS SUGGEST RAIN SHOULD ACTUALLY OCCUR WITHIN THE NEXT 2-3 HOURS...WHICH AS OF THIS WRITING IS PRIMARILY THE DEPARTING MAINLY LIGHT SHOWER ACTIVITY WITHIN THAYER/FILLMORE COUNTIES...AND ALSO THE SMALL CLUSTER OF SHOWERS/ISOLATED STORMS SLIDING INTO THE VALLEY COUNTY AREA. OTHER ISOLATED CONVECTION IS SKIRTING THE FAR SOUTHERN CWA IN KS...WHILE MEANWHILE THE MAJORITY OF THE CWA IS CURRENTLY IN WHAT COULD BE A MULTIPLE-HOUR BREAK FROM SHOWERS/STORMS...ALTHOUGH THAT IS NO GUARANTEE EITHER SO HAVE AT LEAST KEPT MODEST 20-30 POPS GOING IN ALL AREAS THROUGH THE REST OF THE DAY...WITH HIGHER 40S-50S CONCENTRATED IN THE WEST. AS HAS BEEN THE CASE LATELY...THIS IS A WEAKLY-FORCED BUT WEAKLY CAPPED PATTERN OF WEST-NORTHWEST FLOW ALOFT...WITH HOURLY MESOANALYSIS CURRENTLY SUGGESTING TWO SUBTLE SHORTWAVE TROUGHS...ONE CENTERED OVER CENTRAL NEB AND THE OTHER SLIDING THROUGH NORTHERN KS. THESE WAVES ARE INDUCING MODEST THETA-E/MOISTURE ADVECTION WITHIN THE 850-700 MILLIBAR LEVEL...WHICH IS THE MAIN DRIVING FORCE BEHIND THE THUS-FAR ELEVATED ACTIVITY TODAY. AGREE WITH THE STORM PREDICTION CENTER THAT THE MAIN SEVERE WEATHER THREAT SHOULD STAY AT LEAST A FEW COUNTIES WEST OF THE CWA TODAY OVER THE HIGH PLAINS WHERE MID LEVEL LAPSE RATES ARE STEEPER AND MIXED LAYER-CAPE IS MORE FAVORED TO AVERAGE 1000+ J/KG BY MID-LATE AFTERNOON INTO THIS EVENING...BUT EVEN SO...CANNOT COMPLETELY RULE OUT THE RISK OF A STRONG TO MARGINALLY SEVERE STORM LOCALLY EITHER...ESPECIALLY SOUTHWEST OF A LEXINGTON-OSBORNE LINE. AS FOR OTHER FORECAST ELEMENTS TODAY...UNLIKE YESTERDAY WE ARE PROBABLY NOT LOOKING AT A WELL-DEFINED/MULTI-HOUR PERIOD OF CLEARING AS SKIES SHOULD CONTINUE TO AVERAGE PARTLY-MOSTLY CLOUDY AS NEW CONVECTION DEVELOPS UPSTREAM. AS A RESULT...WOULD NOT BE SURPRISED TO SEE SOME PLACES HELD DOWN IN THE LOW-MID 70S FOR HIGHS TODAY. ALTHOUGH DID NOT GO QUITE THIS LOW JUST YET...DID SHAVE ROUGHLY 2-3 DEGREES OFF PREVIOUS HIGHS IN MOST AREAS TO GET THE BALL ROLLING THAT DIRECTION...CALLING FOR THE MAJORITY OF THE CWA TO TOP OUT NO HIGHER THAN UPPER 70S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 405 AM CDT TUE JUN 24 2014 MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND TEMPERATURES. CURRENT SURFACE ANALYSIS HAS A RIDGE OF HIGH PRESSURE ACROSS THE AREA EARLY THIS MORNING. SURROUNDING RADARS SHOW SHOWERS AND THUNDERSTORMS ON THE HIGH PLAINS GRADUALLY MOVING TOWARDS THE EAST. THE SURFACE HIGH IS EXPECTED TO MOVE OFF TO THE EAST. AN UPPER LEVEL WAVE IS EXPECTED TO MOVE INTO THE AREA DURING THE DAY. EXPECT THE CURRENT PRECIPITATION TO CONTINUE TO MOVE TO THE EAST AND INTO THE AREA BY DAYLIGHT. THE THUNDERSTORMS WILL CONTINUE TO MOVE ACROSS THE AREA DURING THE MORNING HOURS AND INTO THE AFTERNOON. THE HRRR AND THE 4KM WRF BOTH HAVE THE MAIN BAND OF THUNDERSTORMS MAINLY THROUGH THE FORECAST AREA BY MID AFTERNOON. THE MAIN DIFFERENCE IS THAT THE HRRR BRINGS IN ANOTHER BAND LATER THIS AFTERNOON. HAVE KEPT CHANCES IN DURING THE LATE AFTERNOON AND INTO THE NIGHT TIME HOURS. SEVERAL TIMES LATELY THERE HAVE BEEN MORE THUNDERSTORMS THAT DEVELOP ON THE HIGH PLAINS DURING THE AFTERNOON. THE THUNDERSTORMS MOVE INTO THE FORECAST AREA LATE EVENING AND OVERNIGHT. THE MUCAPE IS BEST DURING THE AFTERNOON BUT A LITTLE REMAINS THROUGH THE NIGHT. EXPECT THERE COULD BE A STRONG STORM OR TWO AROUND THE AREA THIS AFTERNOON AND EVENING...THEN TURN INTO A RAIN EVENT DURING THE NIGHT TIME HOURS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 405 AM CDT TUE JUN 24 2014 THE BIGGEST CHALLENGE WILL BE DETERMINING CHANCES OF RAIN IN THE LONG TERM. THE ZONAL FLOW WILL GRADUALLY BECOME MORE SOUTHWEST AS AN UPPER LEVEL TROUGH MOVES INTO THE WESTERN UNITED STATE. THIS WILL HELP KICK UP PULSES OF ENERGY INTO THE HIGH/GREAT PLAINS THAT WILL GIVE US A SHOT A SHOWER/THUNDERSTORMS FOR MOST PERIODS OF THE LONG TERM. THE GREATEST CHANCE OF RAIN WILL BE FRIDAY NIGHT AS A WARM FRONT MOVES IN AND THROUGH THE AREA...ALONG WITH AN INCREASED LOW- LEVEL JET AND POTENTIAL STRONG CONVERGENCE NEAR THE NOSE OF THE JET NEARBY. STRONG TO SEVERE STORMS CAN NOT BE RULED OUT...JUDGING BY SEVERE PARAMETERS...FOR MUCH OF THE LONG TERM...BUT NARROWING DOWN A DAY THAT IT WOULD BE MORE LIKELY IS TOO DIFFICULT TO IDENTIFY NOW. TEMPERATURES APPEARED TO BE PRETTY MUCH ON TRACK FROM THE PREVIOUS FORECAST...SO NO MAJOR CHANGES TO TEMPERATURES. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 609 AM CDT TUE JUN 24 2014 THUNDERSTORM CHANCES ARE THE CHALLENGE FOR TODAY. A BAND OF THUNDERSTORMS TO THE WEST OF THE TERMINAL AREA SHOULD MOVE INTO THE AREA IN A FEW HOURS. THE BIG QUESTION IS WHETHER THERE WILL BE A BREAK THIS AFTERNOON AND MORE THUNDERSTORMS TONIGHT OR WHETHER THERE WILL BE MORE THUNDERSTORMS DURING THE DAY WITH LESS DURING THE NIGHT TONIGHT. HAVE KEPT SOME VCTS DURING THE DAY BUT WILL HAVE TO KEEP AN EYE ON THE THUNDERSTORM ACTIVITY. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...PFANNKUCH SHORT TERM...JCB LONG TERM...HEINLEIN AVIATION...JCB
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1213 PM MDT TUE JUN 24 2014 .AVIATION... 18Z TAF CYCLE POSSIBLE STORM ACTIVITY THIS AFTN/EVE EAST OF THE SANGRE DE CRISTO MTNS TO THE EASTERN PLAINS...WITH STRONG TO SEVERE POTENTIAL FOR THE EXTREME NORTHEAST PLAINS. VCSH FOR KLVS AND KTCC BECAUSE OF POTENTIAL FOR SCATTERED SHOWERS AND THUNDERSTORMS. LOW CIGS EXPECTED FOR KLVS...KTCC AND KROW INTO TONIGHT. VFR CONDITIONS FOR OTHER SITES NOT IMPACTED BY STORMS. && 32 .PREV DISCUSSION...542 AM MDT TUE JUN 24 2014... .AVIATION... 12Z TAF CYCLE CLUSTER OF STORMS NEAR THE TX LINE WILL MOVE EAST INTO TX BY ABOUT SUNRISE. DEVELOPING SFC LOW OVER SE COLORADO WILL TURN/BACK WINDS TO SWLY OVER THE EASTERN PLAINS BY AFTERNOON...BRINGING DRIER AIR IN FROM WRN NM. MAIN STORM ACTIVITY TODAY EXPECTED FROM THE EAST SLOPES OF THE NORTHERN SANGRE DE CRISTO MTNS EWD TO THE FAR NE PLAINS. A FEW STRONG TO SEVERE STORMS POSSIBLE THIS AFTERNOON AND EVENING IN UNION AND COLFAX COUNTIES. ISOLD MAINLY DRY SHOWERS OR STORMS EXPECTED ELSEWHERE EAST OF THE CENTRAL MTN CHAIN THIS AFTERNOON AND EVENING WITH SKC OR A FEW FAIR WEATHER CUMULUS WEST. 33 && .PREV DISCUSSION...337 AM MDT TUE JUN 24 2014... .SYNOPSIS... AN ACTIVE WEATHER PATTERN WILL CONTINUE MAINLY FROM THE CENTRAL MOUNTAIN CHAIN EAST TO THE TEXAS BORDER. THIS INCLUDES THE POTENTIAL FOR STRONG TO SEVERE THUNDERSTORMS ACROSS PARTS OF THE EAST WITH THE FOCUS FOR SEVERE WEATHER SHIFTING TO THE NORTHEAST PLAINS LATER TODAY INTO EVENING. AFTER TONIGHT... A GRADUAL DRYING TREND IS EXPECTED FOR MID TO LATE WEEK WITH A MOSTLY DRY FORECAST FOR THURSDAY THROUGH SUNDAY. WE CANNOT RULE OUT ISOLATED THUNDERSTORMS FOR THE NORTHERN MOUNTAINS OR FAR EASTERN PLAINS FOR THE SECOND HALF OF THE WEEK...BUT HOTTER AND DRIER CONDITIONS WILL PREDOMINATE. && .DISCUSSION... MONITORING STRONG TO SEVERE CONVECTION ACROSS PARTS OF THE NORTHEAST AND EAST CENTRAL PLAINS EARLY THIS MORNING. EARLY STAGES OF A DEVELOPING MESOSCALE CONVECTIVE COMPLEX UNDERWAY NORTHWEST OF TUCUMCARI THAT IS SIMILAR TO WHAT THE LATEST 13KM RAP AND 03Z HRRR ADVERTISED IF NOT A LITTLE FARTHER SOUTH. SHALLOW SHORTWAVE TROUGH TRANSLATING EASTWARD COUPLED WITH A BROAD REGION OF UPPER LEVEL DIFLUENCE AIDING THIS EARLY MORNING DEVELOPMENT THAT IS ALIGNED ALONG A NW-SE ORIENTED SURFACE BOUNDARY WITH A STRONG/WELL- DEFINED MOISTURE/INSTABILITY GRADIENT STRETCHING FROM NORTH OF SANTA ROSA SEWD TOWARD THE LUBBOCK AREA. MADE SOME ADJUSTMENTS TO POP/WX GRIDS BUT WILL LIKELY REVISIT JUST BEFORE PUBLISHING. TRENDS AFTER THIS MORNING/S CONVECTIVE COMPLEX WEAKENS AND/OR EXITS TO THE EAST BETWEEN 13Z-15Z WILL BE MORE COMPLICATED... AS WESTWARD-PUSHING OUTFLOW BOUNDARIES MAY REINFORCE LOW LEVEL MOISTURE FIELDS A BIT FARTHER WEST THAN PREVIOUSLY EXPECTED. REGARDLESS... ANY LOW LEVEL MOISTURE WEST OF THE CENTRAL MOUNTAIN CHAIN WILL REMAIN QUITE SHALLOW AND WITH MID- LEVEL DRYING AND SOME LARGE-SCALE SUBSIDENCE DO NOT ANTICIPATE ANY NEED FOR EXPANSION OF ISOLATED POPS EAST OF THE DIVIDE THE RIO GRANDE. DID BEEF UP POPS FOR SC AREAS AS WELL AS THE FAR NE WHERE LOW LEVEL WINDS MAY GRADUALLY BACK TO MORE EASTERLY LATE IN THE DAY INCREASING POTENTIAL FOR SEVERE THERE. LESS ACTIVE TONIGHT INTO WED AM AS MID-LEVEL DRYING ADVANCES EASTWARD BENEATH A GENERAL WESTERLY FLOW REGIME WITH LESS DEFINED INDICATORS FOR LARGE SCALE UPWARD FORCING. EXPECT TO SEE A FAIRLY WELL DEFINED SURFACE DRYLINE WED PM NEAR THE NM/TX LINE WITH A DEEPENING SURFACE LOW OVER SE COLO. THE GFS DEVELOPS A WEAKER SURFACE LOW FARTHER SOUTH...WHICH WOULD AGAIN FAVOR THE FAR NE PLAINS FOR ANOTHER SHOT AT SEVERE BUT OVERALL COVERAGE OF STORMS TRENDING WAY DOWN SAVE FOR AREAS NEAR THE TX LINE AND POSSIBLY NE CORNER. EVEN DRIER/LESS ACTIVE WITH INCREASED WINDINESS FOR THU WITH AGAIN THE FOCUS FOR STORMS NEAR THE NM/TX LINE ALONG THE DRYLINE. BROAD CYCLONIC FLOW SPREADS EASTWARD OVER THE SOUTHERN ROCKIES AND NEW MEXICO BY FRIDAY WITH DRYLINE REGIME PERSISTING. 500MB HEIGHTS THEN REBOUND INTO THE WEEKEND WITH STRONGER RIDGE PATTERN EARLY NEXT WEEK. SHOULD LOSE INFLUENCE OF THE WESTERLIES BY MON/TUE...AND SIGNS THAT IT MAY PERSIST. KJ && .FIRE WEATHER... SIMILAR WEATHER SCENARIO TO MONDAY EXPECTED TODAY. BEST CHANCES FOR SHOWERS AND THUNDERSTORMS REMAINS EAST OF THE CENTRAL MOUNTAIN CHAIN WITH SLIGHTLY LESS ACTIVITY THAN MONDAY AS A SURFACE LOW BEGINS TO DEVELOP OVER SE COLORADO THIS AFTERNOON AND DRY AIR FROM THE WEST BEGINS TO WORK INTO THE CENTRAL AND NORTHEAST HIGHLANDS. WINDS BECOME MORE SOUTHWESTERLY WEDNESDAY...SCOURING OUT MORE GULF MOISTURE FROM THE SOUTHEAST AND EAST-CENTRAL PLAINS WITH SHOWERS AND STORMS PRIMARILY CONFINED TO THE FAR NE PLAINS. DRY WESTERLIES WIN OUT AREAWIDE BY THURSDAY AS LEE SFC TROUGH STRENGTHENS FURTHER. DRY CONDITIONS CONTINUE THROUGH THE WEEKEND ALONG WITH HIGH HAINES VALUES AND GOOD TO EXCELLENT VENTILATION RATES. WEST WINDS INCREASE FRIDAY AS A WEAK UPPER LEVEL TROUGH MOVES EAST THROUGH THE CENTRAL AND NORTHERN ROCKIES FRIDAY NIGHT INTO SATURDAY. CRITICAL FIRE WEATHER CONDITIONS ARE A POSSIBILITY FRIDAY AFTERNOON AND EARLY EVENING...PRIMARILY FROM THE CENTRAL HIGHLANDS NORTHEASTWARD TO THE NORTHEAST PLAINS. GFS AND ECMWF ARE GOOD AGREEMENT THAT WE FINALLY LOSE THE WESTERLIES ALOFT SUNDAY INTO EARLY NEXT WEEK. FOUR CORNERS HIGH BEGINS TO STRENGTHEN AND DRIFT NORTHWARD OVER SOUTHERN AZ AND SW NM SUNDAY...THEN OVER CENTRAL NM MONDAY. SUNDAY APPEARS TO BE THE HOTTEST DAY DURING THE NEXT 7 DAYS AS THE FOUR CORNERS HIGH MOVES OVERHEAD. MODELS HINTING THAT MONSOON MOISTURE MAY BEGIN TO SEEP NORTHWARD INTO PORTIONS OF SOUTHERN AND PERHAPS CENTRAL NM MONDAY AND TUESDAY. 33 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
346 PM EDT TUE JUN 24 2014 .SYNOPSIS... UPPER AIR FEATURE AND COLD FRONT APPROACH TONIGHT. FRONT MOVES INTO MOUNTAIN COUNTIES LATE WEDNESDAY/ WEAKENS WEDNESDAY NIGHT. DRIER/MORE MORE STABLE AIR THURSDAY. MOISTURE/INSTABILITY INCREASE ON FRIDAY. && .NEAR TERM /THROUGH WEDNESDAY/... ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS POPPING UP ACROSS THE FORECAST AREA AS OF 17Z. HRRR SEEMED TO HAVE A FAIRLY GOOD HANDLE ON THIS AND LEANED THAT WAY INITIALLY. THIS GIVES HIGHER POPS ACROSS THE MOUNTAINS AND ALSO IN SE OHIO/OHIO RIVER VALLEY...ALTHOUGH HAVE SCATTERED STORMS ACROSS ENTIRE CWA. MAIN DRIVER OF HIGHER POPS TONIGHT INTO TOMORROW IS UPPER LEVEL SHORTWAVE TROUGH AND SURFACE COLD FRONT. SLOWED POPS DOWN A LITTLE BASED ON 12Z MODELS WITH LIKELY POPS MOVING IN FROM THE WEST EARLY WEDNESDAY MORNING. HAVE THE LIKELY POPS TO OHIO RIVER BY 12Z. THEN HAVE MAX POPS CROSSING WV LOWLANDS 12Z-18Z...MAXING OUT IN THE MOUNTAINS 18Z-20Z...THEN GRADUALLY DECREASING AS VORT MAX HEADS EAST. LIKE A TYPICAL SUMMER COLD FRONT...ANTICIPATE THE ACTUAL BOUNDARY TO BE FAIRLY HARD TO PICK OUT AS IT WEAKENS AND MOVES ACROSS FORECAST AREA...BUT SHOULD WEAKEN AND CROSS CWA FROM NW TO SE 15Z TO 21Z. WITH PWATS AROUND 2.0IN TONIGHT INTO TOMORROW...INCLUDED HEAVY RAIN WORDING WITH WEATHER. ALSO NOTE THE EXCESSIVE RAINFALL AREA FROM WPC. CONSIDERED GOING WITH A FLASH FLOOD WATCH...BUT IN THE END DECIDED TO HOLD OFF BUT EXPAND MENTION OF WATER CONCERNS IN HWO ACROSS THE NORTHERN THIRD OF CWA. MAIN REASON HOLDING BACK ON WATCH AT THIS POINT IS ABUNDANT CLOUD COVER EXPECTED AND BEST UPPER LEVEL FORCING STAYS NORTH...KEEPING CONVECTION A BIT MORE SUBDUED. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... THE BOARD AND WEAKENING MID LEVEL TROF STILL SWINGING THRU AT 00Z THURSDAY. BASED ON FORECAST SOUNDINGS...PICTURING A LOT OF LOW CLOUDS AND SHOWERS LINGERING ACROSS THE MOUNTAIN COUNTIES AT 00Z...BUT NOT A LOT OF LIGHTNING. THE 925 TO 850 MB LOW LEVEL FLOW ALREADY TURNING NICELY TO NORTHWEST BY 00Z THURSDAY...BUT SURFACE FLOW WEAKENS 00Z TO 06Z THURSDAY. SO WILL LEAVE HIGHER SURFACE DEW POINTS WEDNESDAY NIGHT ESPECIALLY IN WV AND SW VA. WILL MENTION SOME FOG OVER HIGH TERRAIN WEDNESDAY NIGHT. THIS WILL ALSO HAVE US FORECASTING MINIMUM TEMPERATURES A BIT HIGHER THAN MOS GUIDANCE...EVEN THOUGH SOME SITES ALREADY BEING RAIN COOLED AT SUNSET. KEEPING THURSDAY DRY FOR MOST OF OUR CWA WITH MORNING CLOUDS IN THE SOUTH BREAKING UP. WILL TRY TO HOLD TEMPERATURES DOWN A BIT THURSDAY BASED ON THE MORNING CLOUDS IN THE SOUTH. DO STILL HAVE 20 POPS LATE THURSDAY IN SW VA AND PORTION OF NE KY. OLD FRONT AND DEW POINT GRADIENT...LINGERS DOWN THE OHIO RIVER ON FRIDAY. WILL NOT JUMP ON THE CMC SOLUTION OF STRONGER MID LEVEL DISTURBANCE SWINGING THRU BY 12Z FRIDAY. IN CONTRAST...12Z GFS AND ECWMF MUCH DRIER. LIKE THE IDEA OF LEAVING OUR POPS IN THE CHANCE RANGE FOR FRIDAY...LIFTING SOUTHWEST TO NORTHEAST DURING THE DAY. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... GENERALLY WENT WITH HPC THINKING WITH SOME TWEAKS. REGION SHOULD BE UNDER THE INFLUENCE OF BUILDING 500 MB HEIGHTS THROUGH MUCH OF THE PERIOD. HOWEVER...MODELS INDICATE RIDGE WILL BREAK DOWN LATE IN THE PERIOD. WILL BE SEVERAL MID-LEVEL TROFS THAT COULD INFLUENCE THE WEATHER ACROSS THE AREA...BUT TIMING WILL BE TOUGH. SO...HAVE TAILORED POPS TO INDICATE MAINLY AFTERNOON AND EVENING SHOWERS/STORMS. WPC TEMPS LOOK GOOD AND WERE GENERALLY FOLLOWED. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... HAVE ISOLATED TO SCATTERED CONVECTION DEVELOPING ACROSS CWA...AND HAVE VCTS IN ALL TAFS THROUGH THE AFTERNOON. INCLUDED A TEMPO AT HTS ANTICIPATING THE LINE OF CONVECTION IN EASTERN KY TO ARRIVE SHORTLY AFTER 21Z. ALSO INCLUDED A TEMPO AT EKN FOR CONVECTION IN THE CENTRAL MOUNTAINS OF WV. EXPECT A DOWNTREND IN CONVECTION OVERNIGHT...BEFORE INCREASING AGAIN WEDNESDAY MORNING AS AN UPPER LEVEL SHORTWAVE TROUGH CROSSES DURING THE DAY. OUTSIDE OF CONVECTION EXPECT VFR INTO TONIGHT. MVFR TO IFR EXPECTED IN ANY CONVECTION. LAV TRIES TO FOG THINGS IN TONIGHT...AT LEAST MVFR...BUT THINK WITH ABUNDANT CLOUDS AND STILL SOME LIGHT WIND IT WILL BE HARD TO GET MUCH FOG. HAVE MORE WIDESPREAD CONVECTION TOMORROW. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: TIMING AND COVERAGE OF SHOWERS AND STORMS COULD VARY. MAY NEED BRIEF IFR AND WIND GUSTS IN STORMS. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07 EDT 1HRLY 16 17 18 19 20 21 22 23 00 01 02 03 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 18Z WEDNESDAY... IFR POSSIBLE IN SHOWERS/THUNDERSTORMS WEDNESDAY AFTERNOON WITH STRATUS/FOG EXPECTED WEDNESDAY NIGHT INTO THURSDAY MORNING FOR SITES RECEIVING RAIN. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JSH/KTB/MZ NEAR TERM...MZ SHORT TERM...KTB LONG TERM...JSH AVIATION...MZ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
210 PM EDT TUE JUN 24 2014 .SYNOPSIS... UPPER AIR FEATURE AND COLD FRONT APPROACH TONIGHT. FRONT DISSIPATES WEDNESDAY AS CROSSING CWA. DRIER AND MORE STABLE AIR EXPECTED THURSDAY. CONVECTION RETURNS FRIDAY. && .NEAR TERM /THROUGH WEDNESDAY/... ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS POPPING UP ACROSS THE FORECAST AREA AS OF 17Z. HRRR SEEMED TO HAVE A FAIRLY GOOD HANDLE ON THIS AND LEANED THAT WAY INITIALLY. THIS GIVES HIGHER POPS ACROSS THE MOUNTAINS AND ALSO IN SE OHIO/OHIO RIVER VALLEY...ALTHOUGH HAVE SCATTERED STORMS ACROSS ENTIRE CWA. MAIN DRIVER OF HIGHER POPS TONIGHT INTO TOMORROW IS UPPER LEVEL SHORTWAVE TROUGH AND SURFACE COLD FRONT. SLOWED POPS DOWN A LITTLE BASED ON 12Z MODELS WITH LIKLEY POPS MOVING IN FROM THE WEST EARLY WEDNESDAY MORNING. HAVE THE LIKELY POPS TO OHIO RIVER BY 12Z. THEN HAVE MAX POPS CROSSING WV LOWLANDS 12Z-18Z...MAXING OUT IN THE MOUNTAINS 18Z-20Z...THEN GRADUALLY DECREASING AS VORT MAX HEADS EAST. LIKE A TYPICAL SUMMER COLD FRONT...ANTICIPATE THE ACTUAL BOUNDARY TO BE FAIRLY HARD TO PICK OUT AS IT WEAKENS AND MOVES ACROSS FORECAST AREA...BUT SHOULD WEAKEN AND CROSS CWA FROM NW TO SE 15Z TO 21Z. WITH PWATS AROUND 2.0IN TONIGHT INTO TOMORROW...INCLUDED HEAVY RAIN WORDING WITH WEATHER. ALSO NOTE THE EXCESSIVE RAINFALL AREA FROM WPC. CONSIDERED GOING WITH A FLASH FLOOD WATCH...BUT IN THE END DECIDED TO HOLD OFF BUT EXPAND MENTION OF WATER CONCERNS IN HWO ACROSS THE NORTHERN THIRD OF CWA. MAIN REASON HOLDING BACK ON WATCH AT THIS POINT IS ABUNDANT CLOUD COVER EXPECTED AND BEST UPPER LEVEL FORCING STAYS NORTH...KEEPING CONVECTION A BIT MORE SUBDUED. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/... UNSETTLED WEATHER PATTERN CONTINUES AS THE OHIO VALLEY REMAINS ON THE SOUTHERN EDGE OF THE WESTERLIES ALOFT. THE GULF OF MEXICO OPENS UP AHEAD OF EACH EMBEDDED SHORT WAVE THAT ROLLS ACROSS THE AREA WITH MOIST AND UNSTABLE AIR RIDING NORTH ON LOW LEVEL SOUTHERLY FLOW. THE RESULT WILL BE GOOD CHANCES FOR SHOWERS AND THUNDERSTORMS WITH EACH SYSTEM. THERE ARE OF COURSE MODEL DIFFERENCES IN THE TIMING AND EXACT TRACK OF EACH SYSTEM...SO WILL FOLLOW WPC/S THINKING CLOSELY. ONE SHORT WAVE WITH THE DEEPER MOISTURE EXITS LATER WEDNESDAY WITH WIDESPREAD CONVECTION DECREASING FROM WEST TO EAST...WITH MOST CONVECTION SHIFTING INTO THE MOUNTAINS WEDNESDAY EVENING AS DRIER AIR ALOFT MOVES IN. EXPECT ALL CONVECTION WILL END FAIRLY EARLY WEDNESDAY NIGHT WITH LOSS OF HEATING. AS FOR THE FRONT ACCOMPANYING THE SHORT WAVE...THERE CONTINUES TO BE UNCERTAINTY AS TO WHETHER IT ACTUALLY MAKES IT ACROSS THE AREA WEDNESDAY. WHETHER IT DOES OR NOT...THE DRIER AIR ABOVE THE SURFACE MOVING IN BEHIND THE SHORT WAVE WILL SHUT OFF CONVECTION LATER WEDNESDAY NIGHT AND THURSDAY. WHAT WILL BE LEFT WILL BE A FLAT SURFACE PRESSURE PATTERN FOR THURSDAY AND TRAPPED LOW LEVEL MOISTURE...WHICH MAY TEMPORARILY MIX OUT SOMEWHAT WITH AFTERNOON MIXING. TEMPS WILL CONTINUE ON THE WARM SIDE THURSDAY...IN THE 80S WITH SUNSHINE...AND STILL SOMEWHAT ON THE HUMID SIDE. NEXT SHORT WAVE APPROACHES FRIDAY WITH SOUTHERLY FLOW RETURNING DEEPER MOISTURE AND INSTABILITY...AND INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS. IT WILL BE VERY WARM AND HUMID WITH TEMPS WELL INTO THE 80S. && .LONG TERM /SATURDAY THROUGH MONDAY/... GENERALLY WENT WITH HPC THINKING WITH SOME TWEAKS. REGION SHOULD BE UNDER THE INFLUENCE OF BUILDING 500 MB HEIGHTS THROUGH MUCH OF THE PERIOD. HOWEVER...MODELS INDICATE RIDGE WILL BREAK DOWN LATE IN THE PERIOD. WILL BE SEVERAL MID-LEVEL TROFS THAT COULD INFLUENCE THE WEATHER ACROSS THE AREA...BUT TIMING WILL BE TOUGH. SO...HAVE TAILORED POPS TO INDICATE MAINLY AFTERNOON AND EVENING SHOWERS/STORMS. WPC TEMPS LOOK GOOD AND WERE GENERALLY FOLLOWED. && .AVIATION /17Z TUESDAY THROUGH SATURDAY/... HAVE ISOLATED TO SCATTERED CONVECTION DEVELOPING ACROSS CWA...AND HAVE VCTS IN ALL TAFS THROUGH THE AFTERNOON. INCLUDED A TEMPO AT HTS ANTICIPATING THE LINE OF CONVECTION IN EASTERN KY TO ARRIVE SHORTLY AFTER 21Z. ALSO INCLUDED A TEMPO AT EKN FOR CONVECTION IN THE CENTRAL MOUNTAINS OF WV. EXPECT A DOWNTREND IN CONVECTION OVERNIGHT...BEFORE INCREASING AGAIN WEDNESDAY MORNING AS AN UPPER LEVEL SHORTWAVE TROUGH CROSSES DURING THE DAY. OUTSIDE OF CONVECTION EXPECT VFR INTO TONIGHT. MVFR TO IFR EXPECTED IN ANY CONVECTION. LAV TRIES TO FOG THINGS IN TONIGHT...AT LEAST MVFR...BUT THINK WITH ABUNDANT CLOUDS AND STILL SOME LIGHT WIND IT WILL BE HARD TO GET MUCH FOG. HAVE MORE WIDESPREAD CONVECTION TOMORROW. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: TIMING AND COVERAGE OF SHOWERS AND STORMS COULD VARY. MAY NEED BRIEF IFR AND WIND GUSTS IN STORMS. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05 EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 18Z WEDNESDAY... IFR POSSIBLE IN SHOWERS/THUNDERSTORMS WEDNESDAY AFTERNOON WITH STRATUS/FOG EXPECTED WEDNESDAY NIGHT INTO THURSDAY MORNING FOR SITES RECEIVING RAIN. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JSH/KTB/MZ NEAR TERM...MZ SHORT TERM...JMV LONG TERM...JSH AVIATION...MZ
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
235 PM CDT TUE JUN 24 2014 .AVIATION... STORMS APPEAR TO BE DEVELOPING OVER METROPLEX WHERE OLD FRONTAL BOUNDARY IS LAYING. MCS/MCV APPROACHING FROM THE WEST WILL PROVIDE LIFT AND THUS CONVECTION IS DEVELOPING WELL AHEAD OF MCS. HAVE ALREADY UPDATED TAFS TO INCLUDE VCTS FOR THE REST OF THIS AFTERNOON AND TO BUMP TEMPO TIMING UP 2 HOURS FROM 22-0Z/5PM TO 7PM AS MOST LIKELY STORM WINDOW...BUT CELLS THAT DEVELOP OVERHEAD AN AIRPORT WILL RESULT IN TSRA BEFORE THAT TEMPO WINDOW SO FURTHER AMENDMENTS LIKELY BASED ON TRENDS. TR.92 .../PREVIOUS AVIATION DISCUSSION/... MAIN CONCERN IS CONVECTIVE POTENTIAL OVER THE REGION THIS AFTERNOON AND EVENING...AND UNFORTUNATELY NO GOOD MODEL GUIDANCE TO RELY ON FOR THIS FORECAST AS THEY ARE NOT IDENTIFYING WITH THE CURRENT MCS/MCV BETWEEN LUBBOCK AND ABILENE. THIS SYSTEM WILL CONTINUE TO MOVE SOUTHEAST ROUGHLY PARALLEL/ALONG AN OLD FRONTAL BOUNDARY WHERE AN AXIS OF HIGH INSTABILITY RESIDES. IN ADDITION...SCATTERED SHOWERS AND STORMS WILL POP-UP DURING THE AFTERNOON WITHIN THIS INSTABILITY AXIS. ALREADY SOME OF THIS CONVECTION IS BUILDING UP SOUTHWEST AND SOUTH OF THE METROPLEX...AND THIS TREND SHOULD CONTINUE WITH FURTHER HEATING AND INCREASING LIFT AHEAD OF THE MCS/MCV TO THE WEST. ESSENTIALLY THERE IS PRETTY HIGH CONFIDENCE THAT STORMS WILL AFFECT THE REGION SOUTH OF THE METROPLEX THIS AFTERNOON AND EVENING...BUT IT IS A MORE DIFFICULT CALL TO DETERMINE WHETHER THE STORMS WILL EXTEND AS FAR NORTH INTO THE METROPLEX TAF SITES. GIVEN THE HIGH AMOUNTS OF UNCAPPED INSTABILITY ALREADY IN PLACE ACROSS THE METROPLEX...IT IS BEST TO CONTINUE A VCTS FORECAST STARTING AT 21-22Z FOR ANY POP-UP STORMS THAT MAY DEVELOP IN THE VICINITY WITH DAYTIME HEATING. CONFIDENCE HAS INCREASED THAT THE MCS TO THE NW WILL HOLD TOGETHER AND REACH THE METROPLEX IN THE 23-02Z WINDOW THIS EVENING FOR INCLUSION OF A TEMPO TSRA THEN. AT WACO CONFIDENCE IS HIGHER THAT MCS WILL REACH THE AREA AROUND 01-03Z AND A TEMPO TSRA IS INDICATED THERE. WILL CONTINUE TO MONITOR LATEST CONVECTIVE TRENDS AND UPDATE AS NECESSARY. OTHERWISE OUTSIDE OF STORMS...VFR WILL PREVAIL WITH LIGHT SOUTH WINDS. TR.92 && .UPDATE... ASIDE FROM A FEW ISOLATED SHOWERS/STORMS ACROSS THE SOUTHEASTERN QUADRANT OF THE CWA...MOST OF THE STORM ACTIVITY IS TO OUR WEST ACROSS THE TEXAS PANHANDLE AND WEST TEXAS. REGARDING RAIN/STORM POTENTIAL FOR THE REMAINDER OF THE DAY...OUR POTENTIAL FOCUSES ON TWO DIFFERENT AREAS. THE FIRST IS A BOUNDARY THAT CURRENTLY LIES ALONG A LINE FROM EMORY TO DFW TO SOUTH OF GRAHAM. THE WINDS NORTH OF THE BOUNDARY ARE FROM THE SOUTHEAST WHILE THE WINDS SOUTH OF THE BOUNDARY ARE FROM THE SOUTH. HOWEVER...DEWPOINTS ACROSS THE BOUNDARY VARY MORE MAKING THE IDENTIFICATION OF THE BOUNDARY EASIER IN THAT REGARD. DEWPOINTS NORTH OF THE BOUNDARY ARE IN THE UPPER 60S WITH 70S SOUTH OF THE BOUNDARY. THE WINDS IN THE METROPLEX HAVE BECOME MORE SOUTHERLY THIS HOUR WITH DEWPOINTS INCREASING TO AROUND 70 SUGGESTING MAYBE THIS BOUNDARY IS LIFTING NORTH SOME. AS TEMPERATURES WARM SOUTH OF THE BOUNDARY INTO THE UPPER 80S/NEAR 90 DEGREES THIS AFTERNOON...CAPE VALUES WILL INCREASE WITH VALUES UP TO 4000 J/KG IN SOME LOCATIONS. WIND SHEAR VALUES WILL BE LOW...GENERALLY LESS THAN 15 MPH...AND AS DESCRIBED IN THIS MORNINGS DISCUSSION...STORMS THIS AFTERNOON COULD QUICKLY BECOME STRONG/SEVERE BUT WILL LIKELY NOT BE ORGANIZED DUE TO THE WEAK SHEAR. HOWEVER...THESE STORMS WILL HAVE A THREAT FOR DAMAGING MICROBURST WINDS...FREQUENT LIGHTNING...AND HEAVY RAINFALL. THE HEAVY RAINFALL MAY RESULT IN NUISANCE FLOODING OR FLASH FLOODING AS STORM MOTIONS WILL BE SLOW AT SPEEDS LESS THAN 10-15 MPH. NEW STORM DEVELOPMENT WILL ALSO BE POSSIBLE ON ANY OUTFLOW BOUNDARIES FROM THIS AFTERNOONS STORMS WHICH COULD INCREASE A LOCALIZED FLASH FLOODING THREAT. THE SECOND AREA OF CONCERN FOR THUNDERSTORMS THIS AFTERNOON IS ASSOCIATED WITH THE COMPLEX OF STORMS CURRENTLY IN THE TEXAS PANHANDLE TO THE EAST OF LUBBOCK. THIS COMPLEX IS RIDING ITS OUTFLOW BOUNDARY AND QUICKLY MOVING SOUTHEAST. WE ANTICIPATE THIS MCS TO REACH OUR WESTERN COUNTIES LATER THIS AFTERNOON OR EARLY EVENING. DESPITE THE WEAK LOW LEVEL WIND FLOW INTO THIS SYSTEM...IT IS LIKELY TO MAINTAIN ITS COMPOSURE ENOUGH TO REACH THE CWA BASED ON ITS COLD POOL INTERACTIONS. IN ADDITION...THE MCS IS HEADING INTO A MORE HUMID AND UNSTABLE ENVIRONMENT ACROSS NORTHWEST AND NORTH TEXAS WHICH WOULD FAVOR ITS MAINTENANCE LONG ENOUGH TO REACH NORTH/CENTRAL TEXAS. WHEN THE COMPLEX REACHES OUR COUNTIES IT COULD BE SEVERE WITH A DAMAGING WIND...HEAVY RAIN...AND POSSIBLY HAIL THREAT. IN ADDITION...STORMS ARE DEVELOPING AHEAD OF THE COMPLEX ACROSS AREAS NORTHWEST OF ABILENE. THIS SUPPORTS AN UNSTABLE ENVIRONMENT ACROSS THE WESTERN PORTIONS OF THE REGION. THESE NEW STORMS ARE NOT MOVING VERY FAST AND WILL LIKELY BE ABSORBED BY THE MCS. FOR THE UPDATE...INCREASED POPS ACROSS THE WEST FOR THE REMAINDER OF THE DAY AND EVENING WITH 50 POPS ACROSS THE WEST AND SOUTH HALVES OF THE CWA. DID NOT ADJUST TEMPERATURES MUCH...BUT HIGH CLOUD DEBRIS AND AREAS OF RAIN WILL LIKELY KEEP TEMPERATURES A FEW DEGREES COOLER IN SOME LOCATIONS. 82/JLD && .PREV DISCUSSION... /ISSUED 411 AM CDT TUE JUN 24 2014/ 08Z/3AM SURFACE ANALYSIS SHOWED A STATIONARY BOUNDARY IN PLACE FROM SULPHUR SPRINGS TO BURLESON TO BRECKENRIDGE. THERE WERE WEAK GRADIENTS OF BOTH TEMPERATURE AND DEW POINT ALONG THE BOUNDARY WITH COOLER VALUES LOCATED NORTH OF THE BOUNDARY. LOOKING AT THE GRADIENT OF EITHER TEMPERATURE OR DEW POINT ALONG THIS BOUNDARY IS NOT VERY IMPRESSIVE...HOWEVER...OBJECTIVE ANALYSIS INDICATES THAT THIS RESULTS IN A FAIRLY TIGHT GRADIENT OF THETA-E WITH A CHANGE OF ALMOST 8 KELVIN FROM NORTH TO SOUTH ALONG THIS BOUNDARY. AS A RESULT...THINK THAT THIS BOUNDARY WILL HANG AROUND THROUGH AT LEAST THE MORNING HOURS OF THE DAY TODAY. IT MAY HOLD SOME IDENTITY INTO THE AFTERNOON HOURS AS WELL IF SHORT RANGE MODEL GUIDANCE IS ACCURATE. THE 07Z RAP INDICATED THAT THIS BOUNDARY EXTENDS UP TO THE 850 MB LEVEL WHERE THE THETA-E GRADIENT IS EVEN MORE PRONOUNCED...SHOWING A THETA-E CHANGE OF 12-16 KELVIN ALONG THE BOUNDARY THROUGH THIS MORNING. THE MAIN POINT OF THIS ANALYSIS IS THAT THIS BOUNDARY APPEARS AS THROUGH IT IS STRONG ENOUGH TO REMAIN SOMEWHERE IN THE CWA AS WE APPROACH THE PEAK HEATING HOURS OF THE DAY. IF IT STILL EXISTS THIS AFTERNOON...IT COULD BE A BIG PLAYER IN THUNDERSTORM INITIATION TODAY. REGARDING THUNDERSTORM CHANCES FOR TODAY...ALMOST ALL GUIDANCE INDICATES THAT THIS BOUNDARY IS IMPORTANT FOR THUNDERSTORM CHANCES TODAY AS MOST GUIDANCE ADVERTISES QPF ALONG THIS BOUNDARY SOMETIME THIS MORNING THROUGH THIS AFTERNOON. THE TIMING OF WHEN THIS QPF SHOWS UP IS THE KEY DIFFERENCE AMONGST THE MODELS. MANY OF THE HIGH-RESOLUTION MODELS SHOW QPF OR SIMULATED REFLECTIVITY DEVELOPING ALONG THIS BOUNDARY JUST AFTER SUNRISE THIS MORNING. IF THIS OCCURS...THE CONVECTION THAT IS INITIATED WILL PROBABLY BE RELATIVELY WEAK IN NATURE AND MAY BE SOMEWHAT ELEVATED AS MOSTLY CLEAR SKIES TONIGHT OVER THE BOUNDARY HAS ALLOWED A NICE NOCTURNAL INVERSION TO SET UP OVER THE AREA. IT`S HARD TO SAY WHETHER THIS CONVECTION WOULD BE ENOUGH TO IMPACT THE BOUNDARY OR NOT IF IT DEVELOPS THIS MORNING. IF NOTHING ELSE...IT WILL ADD CLOUDS OVER THE WARMER SIDE OF THE BOUNDARY ALLOWING DIFFERENTIAL HEATING TO REDUCE THE IDENTITY OF THE BOUNDARY BY WARMING THE COOL SIDE AND KEEPING THE WARM SIDE SHIELDED FROM SUNSHINE/HEATING. IT`S PROBABLY FOR THIS REASON THAT MOST HIGH RESOLUTION GUIDANCE MEMBERS HAVE MORNING CONVECTION ALONG AND SOUTH OF THIS BOUNDARY WITH LITTLE TO NO ADDITIONAL PRECIPITATION THIS AFTERNOON. IF THERE IS LITTLE TO NO ACTIVITY ALONG THE BOUNDARY THIS MORNING...THIS BOUNDARY PROBABLY HAS A BETTER CHANCE AT INITIATING STRONG THUNDERSTORMS ACROSS NORTH OR CENTRAL TEXAS THIS AFTERNOON. HIGH RESOLUTION GUIDANCE IS USUALLY FAIRLY RELIABLE WHEN CONSISTENTLY SHOWING A SIMULATED REFLECTIVITY SIGNAL OF THUNDERSTORM INITIATION ALONG A COMMON BOUNDARY AROUND A COMMON TIME. THEREFORE...THERE MAY BE A SLIGHTLY BETTER CHANCE THAT STORMS DEVELOP ALONG THE BOUNDARY THIS MORNING RATHER THAN HOLDING OFF UNTIL THIS AFTERNOON. THE ONLY REASON TO DOUBT SOME OF THE MODELS SHOWING THIS MORNING CONVECTION IS THE LACK OF RESPONSE IN THE REST OF THE MASS FIELDS WHERE THE QPF IS LOCATED. THAT IS...SOME POSITIVE QPF SHOWS UP SOUTH OF THE BOUNDARY...THIS SEEMS TO MAKE SENSE...HOWEVER THERE IS NO INCREASE IN MID-LEVEL RELATIVE HUMIDITY AND NO LOW-LEVEL RESPONSE IN THE WIND FIELDS. BRINGING MODEL LOGIC INTO THE REAL WORLD...THAT`S LIKE SAYING...WE`RE GOING TO HAVE RAIN...BUT NO CLOUDS. IT DOESN`T MAKE SENSE. AS A RESULT...IT IS POSSIBLE THAT THE MODELS ARE SIMPLY PUTTING QPF OUT THERE BECAUSE THERE`S A BOUNDARY AND WE HAVE SOME MOISTURE AND CAPE IN PLACE SOUTH OF THE BOUNDARY. FOR MODELS THAT DO NOT SHOW MUCH ACTIVITY ALONG THE BOUNDARY THIS MORNING...THOSE SOLUTIONS REALLY RAMP UP THE CAPE AND MOISTURE POOLING SOUTH OF THIS BOUNDARY THIS AFTERNOON. THOSE MODELS INDICATE LOWER TO MID-70S DEW POINTS POOLING UP JUST SOUTH OF THE DFW AREA THIS AFTERNOON...RESULTING IN OVER 4000 J/KG OF CAPE. GRANTED...THERE IS VERY WEAK WIND SHEAR...SO EVEN IF STORMS DEVELOP IN THIS ENVIRONMENT THEY PROBABLY WILL NOT BE VERY ORGANIZED. THAT SAID...ANY STORMS THAT DEVELOP WITH 4000 J/KG OF CAPE WILL GET BIG...FAST. LOCALLY HEAVY RAINFALL AND MICROBURSTS WOULD BE THE PRIMARY HAZARDS IF THIS SCENARIO PANS OUT. ALSO...IF THUNDERSTORMS DO NOT DEVELOP THIS MORNING...THE BOUNDARY WILL PROBABLY MOVE A BIT WITH THE WESTERN PART OF THE BOUNDARY MOVING NORTH. IN THIS SCENARIO THE BOUNDARY WILL BE LOCATED NEAR A BOWIE TO GRAPEVINE TO EMORY LINE BEFORE THUNDERSTORMS ARE MOST LIKELY TO DEVELOP. WITH WATER VAPOR SATELLITE IMAGERY SHOWING A COUPLE OF WEAK SHORTWAVE TROUGHS OVER COLORADO AND NEW MEXICO EARLY THIS MORNING...WENT AHEAD AND BUMPED UP POPS A BIT FOR THIS AFTERNOON JUST IN CASE THIS SCENARIO PANS OUT. THIS FORECAST PROBLEM SHOULD AT LEAST BE FAIRLY EASY TO FIGURE OUT TODAY...IF WE END UP WITH SCATTERED STORMS ALONG THE BOUNDARY THAT PERSIST FOR AT LEAST A FEW HOURS THIS MORNING...WE HAVE A BETTER CHANCE AT WASHING OUT OUR BOUNDARY...MAKING AFTERNOON THUNDERSTORM CHANCES LESS LIKELY. IF THERE IS BRIEF OR NO THUNDERSTORM ACTIVITY ALONG THE BOUNDARY THIS MORNING...WE COULD SEE SOME SCATTERED STRONG STORMS DEVELOP ACROSS MUCH OF NORTH AND CENTRAL TEXAS THIS AFTERNOON. HAVE POPS IN THE 20 TO 50 PERCENT RANGE TODAY DUE TO UNCERTAINTY WITH REGARDS TO HOW TODAY WILL PLAY OUT. BY LATE THIS AFTERNOON...MOST MODELS HAVE THIS BOUNDARY GETTING WASHED OUT BY PERSISTENT SOUTHERLY FLOW AND STRONG DAYTIME HEATING. FOR TONIGHT...IF WE GET A LARGE CLUSTER OF STORMS TO PERSIST THIS AFTERNOON...WE COULD SEE SOME OF THIS ACTIVITY CONTINUE ACROSS THE CWA THROUGH THE OVERNIGHT HOURS. ANY LINGERING SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE MUCH WEAKER THAN THIS AFTERNOON. OTHERWISE...IF NOTHING GETS GOING THIS AFTERNOON...OUR ATTENTION THEN TURNS TO THE HIGH PLAINS WHERE HIGH RESOLUTION MODELS CONSISTENTLY SHOW A SQUALL LINE ORGANIZING LATE TONIGHT. IF THE SQUALL LINE BECOMES STRONG ENOUGH...IT WILL CREATE ITS OWN MINI- WEATHER SYSTEM THAT COULD PROPAGATE IT SOUTHEAST OVER NORTH TEXAS BY EARLY WEDNESDAY MORNING. CONFIDENCE IN THIS IS NOT AS GREAT AS IT WAS FOR YESTERDAY MORNING...MAINLY BECAUSE LOW-LEVEL SHEAR IS SOMEWHAT LACKING IN MOST MODEL SOLUTIONS. LOW-LEVEL WIND SHEAR IS ONE OF THE KEY FACTORS THAT HELPS BALANCE COLD-POOL STRENGTH AND REALLY HELPS LINEAR CONVECTIVE SYSTEMS BECOME ORGANIZED INTO THEIR OWN MINI-WEATHER SYSTEM. IN THE ABSENCE OF STRONGER LOW-LEVEL SHEAR...THESE STORM COMPLEXES STILL BECOME QUITE STRONG WHERE THEY ORIGINATE...BUT TEND TO LOSE THEIR COLD POOLS AND DISSIPATE WHEN THEY BEGIN TO PROPAGATE AWAY FROM THE HIGH PLAINS. BECAUSE OF THE LACK OF BETTER LOW-LEVEL SHEAR...ONLY WENT WITH 30 POPS FOR THIS POSSIBILITY FOR THE FAR NORTHWESTERN CWA EARLY WEDNESDAY MORNING. WEDNESDAY...MODELS ARE FAIRLY CONSISTENT IN BRINGING A SHORTWAVE TROUGH SOUTH ACROSS THE RED RIVER TOMORROW AFTERNOON. ASSUMING THIS PANS OUT...EXPECT SCATTERED THUNDERSTORMS TO DEVELOP NORTH OF INTERSTATE 20 TOMORROW AFTERNOON AND THEN MOVE SOUTHEAST IN THE WEAK NORTHWEST FLOW ALOFT. ALSO...MODELS ARE SHOWING A FAIRLY CONSISTENT SIGNAL OF A STRONGER THAN NORMAL SEA-BREEZE BOUNDARY MOVING NORTH FROM THE GULF COAST TOMORROW. AT LEAST THAT`S WHAT IT LOOKS LIKE IN THE MID-LEVEL RELATIVE HUMIDITY FIELDS. AT ANY RATE...WITH THE CONSISTENCY OF MODELS SHOWING QPF...WITH CLOUDS...MOVING IN FROM THE GULF COAST TOMORROW AFTERNOON...WENT AHEAD AND KEPT SOME HIGHER POPS OVER THE SOUTHEASTERN CWA. THURSDAY...MODELS CONTINUE TO SHOW THAT THE WEDNESDAY SHORTWAVE TROUGH WILL SORT OF MEANDER SOUTH AND JUST BECOME A GENERAL WEAKNESS ALOFT STUCK IN BETWEEN UPPER LEVEL RIDGES TO OUR WEST AND EAST. MODELS ARE SHOWING THAT THE WESTERN RIDGE WILL BEGIN TO AMPLIFY A BIT THURSDAY AFTERNOON...POSSIBLY SPREADING SOME FORCING FOR SUBSIDENCE OVER THE FAR WESTERN CWA. AS A RESULT...KEPT HIGHEST POP CHANCES FOR THURSDAY ALONG AND EAST OF INTERSTATE 35 AS THIS IS FURTHER REMOVED FROM THE RIDGE AND STILL WELL WITHIN THE MODEL CONSENSUS LOCATION OF THE COL/UPPER LEVEL WEAKNESS AREA. WE WILL STILL HAVE PLENTY OF MOISTURE WITH LITTLE CAP IN PLACE FOR AFTERNOON THUNDERSTORM CHANCES EAST OF INTERSTATE 35...SO KEPT POPS IN THE 30-40 PERCENT RANGE AT THIS TIME. FRIDAY THROUGH EARLY NEXT WEEK...THE GFS CONTINUES TO SHOW THAT A STRONG WEST COAST UPPER TROUGH WILL MOVE EASTWARDS OVER THE ROCKIES BY FRIDAY AFTERNOON. THE GFS HAS BEEN SHOWING THIS RESULTING IN LAYING THE NORTHERN MEXICO UPPER RIDGE OVER NORTH TEXAS BY FRIDAY...AND HOLDING IN PLACE THROUGH THE UPCOMING WEEKEND. THERE ARE STILL SOME MODEL SOLUTIONS THAT INDICATE THAT UPPER LEVEL RIDGING WILL STAY WEST RESULTING IN A PERSISTENT WEAKNESS ALOFT OVER PARTS OF THE AREA THIS WEEKEND...HOWEVER THE GFS HAS BEEN EXTREMELY CONSISTENT WITH THIS SOLUTION...AND AS RESULT WAS RELIED UPON HEAVILY IN THIS FORECAST. THE GFS HAS UPPER LEVEL RIDING IN PLACE OVER NORTH TEXAS FROM FRIDAY THROUGH THE MIDDLE OF NEXT WEEK...WITH RIDGING ONLY INCREASING IN INTENSITY EARLY NEXT WEEK. WENT WITH A DRY FORECAST FOR THE ENTIRE CWA DURING THIS PERIOD AS A RESULT. ALSO WENT AHEAD AND GRADUALLY RAISED TEMPERATURES THROUGH THIS PERIOD. IF THIS VERIFIES...WE MAY GET INTO OUR FIRST 100 DEGREE HIGHS HERE BY TUESDAY OR WEDNESDAY OF NEXT WEEK. THAT`S A LONG WAYS OUT OF COURSE...BUT THE PATTERN LOOKS HOT AND DRY FOR NOW. CAVANAUGH && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 75 93 75 91 75 / 40 40 20 30 10 WACO, TX 73 90 73 92 76 / 50 50 20 30 10 PARIS, TX 72 90 72 89 72 / 20 40 20 40 20 DENTON, TX 73 91 73 91 74 / 30 40 20 30 10 MCKINNEY, TX 74 92 74 91 74 / 30 40 20 40 20 DALLAS, TX 75 92 74 91 75 / 40 40 20 40 20 TERRELL, TX 76 93 76 92 75 / 40 30 20 40 20 CORSICANA, TX 73 90 73 91 75 / 50 50 20 40 20 TEMPLE, TX 72 90 73 90 76 / 50 50 20 30 20 MINERAL WELLS, TX 72 90 71 90 74 / 50 30 20 20 10 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ /
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1249 PM CDT TUE JUN 24 2014 .DISCUSSION... 18Z AVIATION DISCUSSION BELOW. && .AVIATION... WIDELY-SCATTERED REGIONAL SHOWERS THAT WILL MOST LIKELY AFFECT MOST TERMINALS THROUGH THE DAY...DISCRETE THUNDERSTORM CELLS COVERED BY MID TO LATE AFTERNOON TEMPOS. CLUSTERS OF RAIN WILL CREATE BRIEF (L)IFR CONDITIONS WITHIN HEAVY RAIN LIMITING VISIBILITIES TO A MILE OR UNDER. STRONGEST CELLS COULD PUT OUT DOWNBURST WINDS IN EXCESS OF 30 KTS IN GUST. QUIET VFR OVERNIGHT...LULL WILL COME TO END SHORTLY AFTER SUNRISE TOMORROW ONCE ATMOSPHERE RECHARGES AND VCSH COMMENCE AFTER 25/14Z. WET GROUND WILL INTRODUCE THE CHANCE FOR MVFR DECKS AND/OR VISIBILITIES BETWEEN 25/09-13Z...ESPECIALLY OVER HUBS THAT RECEIVE A GOOD SOAKING TODAY. 31 && .PREV DISCUSSION... /ISSUED 939 AM CDT TUE JUN 24 2014/ UPDATE... SEE MORNING UPDATE. DISCUSSION... AT 13Z...A WEAK OUTFLOW BOUNDARY WAS OVER CENTRAL TEXAS AND SFC HIGH PRESSURE WAS OVER THE NORTHERN GULF COAST. 12Z CRP SOUNDINGS SHOWS PW VALUES OF 2.00 INCHES AND LCH WAS NEAR 1.80 INCHES. CONVECTIVE TEMP IS AROUND 84 AT CRP AND AROUND 88 DEGREES AT LCH. AT 850 MB...A MOIST AXIS EXTENDED FROM NORTH TO SOUTH FROM BRO TO FWD WITH 850 MB DEW PTS BETWEEN 15-17 C ACROSS SE TX. AN 850 TROUGH AXIS EXTENDED FROM SHV TO AROUND AUS. AT 700 MB...THE BEST MSTR WAS TO THE NE OF THE REGION BUT ANOTHER TROUGH AXIS EXTENDED FROM ABOUT DFW TO DRT. AT 250 MB...DIVERGENCE WAS NOTED OVER EAST TEXAS AND ALSO OVER WEST TEXAS WITH A SPEED MAX OVER SOUTH TEXAS. SINCE CONVECTIVE TEMPS ARE RELATIVELY LOW WITH THE ABUNDANCE OF MID LEVEL BOUNDARIES AND EXPECTED UPPER LEVEL DIVERGENCE...FEEL CONVECTION WILL INCREASE RATHER QUICKLY THIS MORNING INTO THIS AFTN. RAISED POPS TO LIKELY OVER THE CENTRAL ZONES AND HIGH END CHANCE ELSEWHERE. THE RAP AND ARW ALSO SUPPORT WIDESPREAD COVERAGE LATER TODAY. CLOUDS AND RAIN COOLED AIR WILL WREAK HAVOC WITH MAX TEMPS BUT WILL MAINTAIN CURRENT FCST VALUES FOR NOW. NEW ZONES OUT BY 1000 AM. 43 && .MARINE... RADAR SHOWING A FEW SHOWERS AND POSSIBLY A THUNDERSTORM STREAMING NORTHWARD OVER THE GULF COASTAL WATERS EARLY THIS MORNING AND SHOULD SEE THESE ISOLATED TO SCATTERED CELLS TODAY...WITH GREATER COVERAGE LIKELY WED AND THU. WINDS TODAY AND WEDNESDAY SHOULD REMAIN MOSTLY IN THE 10 TO 15 KNOT RANGE...BUT WILL LIKELY BUMP UP MORE 15 TO 20 KNOTS AND POSSIBLY HIGHER WED NIGHT AND THURSDAY AS ONSHORE FLOW INCREASES IN RESPONSE TO TIGHTENING PRESSURE GRADIENT. ALONG WITH THE INCREASING WINDS...EXPECT SEAS TO INCREASE IN THAT THURSDAY AND FRIDAY TIME FRAME. WITH THE INCREASING WINDS AND SEAS WOULD EXPECT AT LEAST SCEC AND POSSIBLY SCA FOR LATE IN THE WEEK. 46 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 74 89 75 91 75 / 30 60 20 40 20 HOUSTON (IAH) 75 89 76 90 76 / 30 60 30 60 20 GALVESTON (GLS) 81 87 81 89 80 / 40 50 40 50 30 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...43 AVIATION/MARINE...31
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1247 PM CDT TUE JUN 24 2014 .AVIATION... MAIN CONCERN IS CONVECTIVE POTENTIAL OVER THE REGION THIS AFTERNOON AND EVENING...AND UNFORTUNATELY NO GOOD MODEL GUIDANCE TO RELY ON FOR THIS FORECAST AS THEY ARE NOT IDENTIFYING WITH THE CURRENT MCS/MCV BETWEEN LUBBOCK AND ABILENE. THIS SYSTEM WILL CONTINUE TO MOVE SOUTHEAST ROUGHLY PARALLEL/ALONG AN OLD FRONTAL BOUNDARY WHERE AN AXIS OF HIGH INSTABILITY RESIDES. IN ADDITION...SCATTERED SHOWERS AND STORMS WILL POP-UP DURING THE AFTERNOON WITHIN THIS INSTABILITY AXIS. ALREADY SOME OF THIS CONVECTION IS BUILDING UP SOUTHWEST AND SOUTH OF THE METROPLEX...AND THIS TREND SHOULD CONTINUE WITH FURTHER HEATING AND INCREASING LIFT AHEAD OF THE MCS/MCV TO THE WEST. ESSENTIALLY THERE IS PRETTY HIGH CONFIDENCE THAT STORMS WILL AFFECT THE REGION SOUTH OF THE METROPLEX THIS AFTERNOON AND EVENING...BUT IT IS A MORE DIFFICULT CALL TO DETERMINE WHETHER THE STORMS WILL EXTEND AS FAR NORTH INTO THE METROPLEX TAF SITES. GIVEN THE HIGH AMOUNTS OF UNCAPPED INSTABILITY ALREADY IN PLACE ACROSS THE METROPLEX...IT IS BEST TO CONTINUE A VCTS FORECAST STARTING AT 21-22Z FOR ANY POP-UP STORMS THAT MAY DEVELOP IN THE VICINITY WITH DAYTIME HEATING. CONFIDENCE HAS INCREASED THAT THE MCS TO THE NW WILL HOLD TOGETHER AND REACH THE METROPLEX IN THE 23-02Z WINDOW THIS EVENING FOR INCLUSION OF A TEMPO TSRA THEN. AT WACO CONFIDENCE IS HIGHER THAT MCS WILL REACH THE AREA AROUND 01-03Z AND A TEMPO TSRA IS INDICATED THERE. WILL CONTINUE TO MONITOR LATEST CONVECTIVE TRENDS AND UPDATE AS NECESSARY. OTHERWISE OUTSIDE OF STORMS...VFR WILL PREVAIL WITH LIGHT SOUTH WINDS. TR.92 && .UPDATE... ASIDE FROM A FEW ISOLATED SHOWERS/STORMS ACROSS THE SOUTHEASTERN QUADRANT OF THE CWA...MOST OF THE STORM ACTIVITY IS TO OUR WEST ACROSS THE TEXAS PANHANDLE AND WEST TEXAS. REGARDING RAIN/STORM POTENTIAL FOR THE REMAINDER OF THE DAY...OUR POTENTIAL FOCUSES ON TWO DIFFERENT AREAS. THE FIRST IS A BOUNDARY THAT CURRENTLY LIES ALONG A LINE FROM EMORY TO DFW TO SOUTH OF GRAHAM. THE WINDS NORTH OF THE BOUNDARY ARE FROM THE SOUTHEAST WHILE THE WINDS SOUTH OF THE BOUNDARY ARE FROM THE SOUTH. HOWEVER...DEWPOINTS ACROSS THE BOUNDARY VARY MORE MAKING THE IDENTIFICATION OF THE BOUNDARY EASIER IN THAT REGARD. DEWPOINTS NORTH OF THE BOUNDARY ARE IN THE UPPER 60S WITH 70S SOUTH OF THE BOUNDARY. THE WINDS IN THE METROPLEX HAVE BECOME MORE SOUTHERLY THIS HOUR WITH DEWPOINTS INCREASING TO AROUND 70 SUGGESTING MAYBE THIS BOUNDARY IS LIFTING NORTH SOME. AS TEMPERATURES WARM SOUTH OF THE BOUNDARY INTO THE UPPER 80S/NEAR 90 DEGREES THIS AFTERNOON...CAPE VALUES WILL INCREASE WITH VALUES UP TO 4000 J/KG IN SOME LOCATIONS. WIND SHEAR VALUES WILL BE LOW...GENERALLY LESS THAN 15 MPH...AND AS DESCRIBED IN THIS MORNINGS DISCUSSION...STORMS THIS AFTERNOON COULD QUICKLY BECOME STRONG/SEVERE BUT WILL LIKELY NOT BE ORGANIZED DUE TO THE WEAK SHEAR. HOWEVER...THESE STORMS WILL HAVE A THREAT FOR DAMAGING MICROBURST WINDS...FREQUENT LIGHTNING...AND HEAVY RAINFALL. THE HEAVY RAINFALL MAY RESULT IN NUISANCE FLOODING OR FLASH FLOODING AS STORM MOTIONS WILL BE SLOW AT SPEEDS LESS THAN 10-15 MPH. NEW STORM DEVELOPMENT WILL ALSO BE POSSIBLE ON ANY OUTFLOW BOUNDARIES FROM THIS AFTERNOONS STORMS WHICH COULD INCREASE A LOCALIZED FLASH FLOODING THREAT. THE SECOND AREA OF CONCERN FOR THUNDERSTORMS THIS AFTERNOON IS ASSOCIATED WITH THE COMPLEX OF STORMS CURRENTLY IN THE TEXAS PANHANDLE TO THE EAST OF LUBBOCK. THIS COMPLEX IS RIDING ITS OUTFLOW BOUNDARY AND QUICKLY MOVING SOUTHEAST. WE ANTICIPATE THIS MCS TO REACH OUR WESTERN COUNTIES LATER THIS AFTERNOON OR EARLY EVENING. DESPITE THE WEAK LOW LEVEL WIND FLOW INTO THIS SYSTEM...IT IS LIKELY TO MAINTAIN ITS COMPOSURE ENOUGH TO REACH THE CWA BASED ON ITS COLD POOL INTERACTIONS. IN ADDITION...THE MCS IS HEADING INTO A MORE HUMID AND UNSTABLE ENVIRONMENT ACROSS NORTHWEST AND NORTH TEXAS WHICH WOULD FAVOR ITS MAINTENANCE LONG ENOUGH TO REACH NORTH/CENTRAL TEXAS. WHEN THE COMPLEX REACHES OUR COUNTIES IT COULD BE SEVERE WITH A DAMAGING WIND...HEAVY RAIN...AND POSSIBLY HAIL THREAT. IN ADDITION...STORMS ARE DEVELOPING AHEAD OF THE COMPLEX ACROSS AREAS NORTHWEST OF ABILENE. THIS SUPPORTS AN UNSTABLE ENVIRONMENT ACROSS THE WESTERN PORTIONS OF THE REGION. THESE NEW STORMS ARE NOT MOVING VERY FAST AND WILL LIKELY BE ABSORBED BY THE MCS. FOR THE UPDATE...INCREASED POPS ACROSS THE WEST FOR THE REMAINDER OF THE DAY AND EVENING WITH 50 POPS ACROSS THE WEST AND SOUTH HALVES OF THE CWA. DID NOT ADJUST TEMPERATURES MUCH...BUT HIGH CLOUD DEBRIS AND AREAS OF RAIN WILL LIKELY KEEP TEMPERATURES A FEW DEGREES COOLER IN SOME LOCATIONS. 82/JLD && .PREV DISCUSSION... /ISSUED 411 AM CDT TUE JUN 24 2014/ 08Z/3AM SURFACE ANALYSIS SHOWED A STATIONARY BOUNDARY IN PLACE FROM SULPHUR SPRINGS TO BURLESON TO BRECKENRIDGE. THERE WERE WEAK GRADIENTS OF BOTH TEMPERATURE AND DEW POINT ALONG THE BOUNDARY WITH COOLER VALUES LOCATED NORTH OF THE BOUNDARY. LOOKING AT THE GRADIENT OF EITHER TEMPERATURE OR DEW POINT ALONG THIS BOUNDARY IS NOT VERY IMPRESSIVE...HOWEVER...OBJECTIVE ANALYSIS INDICATES THAT THIS RESULTS IN A FAIRLY TIGHT GRADIENT OF THETA-E WITH A CHANGE OF ALMOST 8 KELVIN FROM NORTH TO SOUTH ALONG THIS BOUNDARY. AS A RESULT...THINK THAT THIS BOUNDARY WILL HANG AROUND THROUGH AT LEAST THE MORNING HOURS OF THE DAY TODAY. IT MAY HOLD SOME IDENTITY INTO THE AFTERNOON HOURS AS WELL IF SHORT RANGE MODEL GUIDANCE IS ACCURATE. THE 07Z RAP INDICATED THAT THIS BOUNDARY EXTENDS UP TO THE 850 MB LEVEL WHERE THE THETA-E GRADIENT IS EVEN MORE PRONOUNCED...SHOWING A THETA-E CHANGE OF 12-16 KELVIN ALONG THE BOUNDARY THROUGH THIS MORNING. THE MAIN POINT OF THIS ANALYSIS IS THAT THIS BOUNDARY APPEARS AS THROUGH IT IS STRONG ENOUGH TO REMAIN SOMEWHERE IN THE CWA AS WE APPROACH THE PEAK HEATING HOURS OF THE DAY. IF IT STILL EXISTS THIS AFTERNOON...IT COULD BE A BIG PLAYER IN THUNDERSTORM INITIATION TODAY. REGARDING THUNDERSTORM CHANCES FOR TODAY...ALMOST ALL GUIDANCE INDICATES THAT THIS BOUNDARY IS IMPORTANT FOR THUNDERSTORM CHANCES TODAY AS MOST GUIDANCE ADVERTISES QPF ALONG THIS BOUNDARY SOMETIME THIS MORNING THROUGH THIS AFTERNOON. THE TIMING OF WHEN THIS QPF SHOWS UP IS THE KEY DIFFERENCE AMONGST THE MODELS. MANY OF THE HIGH-RESOLUTION MODELS SHOW QPF OR SIMULATED REFLECTIVITY DEVELOPING ALONG THIS BOUNDARY JUST AFTER SUNRISE THIS MORNING. IF THIS OCCURS...THE CONVECTION THAT IS INITIATED WILL PROBABLY BE RELATIVELY WEAK IN NATURE AND MAY BE SOMEWHAT ELEVATED AS MOSTLY CLEAR SKIES TONIGHT OVER THE BOUNDARY HAS ALLOWED A NICE NOCTURNAL INVERSION TO SET UP OVER THE AREA. IT`S HARD TO SAY WHETHER THIS CONVECTION WOULD BE ENOUGH TO IMPACT THE BOUNDARY OR NOT IF IT DEVELOPS THIS MORNING. IF NOTHING ELSE...IT WILL ADD CLOUDS OVER THE WARMER SIDE OF THE BOUNDARY ALLOWING DIFFERENTIAL HEATING TO REDUCE THE IDENTITY OF THE BOUNDARY BY WARMING THE COOL SIDE AND KEEPING THE WARM SIDE SHIELDED FROM SUNSHINE/HEATING. IT`S PROBABLY FOR THIS REASON THAT MOST HIGH RESOLUTION GUIDANCE MEMBERS HAVE MORNING CONVECTION ALONG AND SOUTH OF THIS BOUNDARY WITH LITTLE TO NO ADDITIONAL PRECIPITATION THIS AFTERNOON. IF THERE IS LITTLE TO NO ACTIVITY ALONG THE BOUNDARY THIS MORNING...THIS BOUNDARY PROBABLY HAS A BETTER CHANCE AT INITIATING STRONG THUNDERSTORMS ACROSS NORTH OR CENTRAL TEXAS THIS AFTERNOON. HIGH RESOLUTION GUIDANCE IS USUALLY FAIRLY RELIABLE WHEN CONSISTENTLY SHOWING A SIMULATED REFLECTIVITY SIGNAL OF THUNDERSTORM INITIATION ALONG A COMMON BOUNDARY AROUND A COMMON TIME. THEREFORE...THERE MAY BE A SLIGHTLY BETTER CHANCE THAT STORMS DEVELOP ALONG THE BOUNDARY THIS MORNING RATHER THAN HOLDING OFF UNTIL THIS AFTERNOON. THE ONLY REASON TO DOUBT SOME OF THE MODELS SHOWING THIS MORNING CONVECTION IS THE LACK OF RESPONSE IN THE REST OF THE MASS FIELDS WHERE THE QPF IS LOCATED. THAT IS...SOME POSITIVE QPF SHOWS UP SOUTH OF THE BOUNDARY...THIS SEEMS TO MAKE SENSE...HOWEVER THERE IS NO INCREASE IN MID-LEVEL RELATIVE HUMIDITY AND NO LOW-LEVEL RESPONSE IN THE WIND FIELDS. BRINGING MODEL LOGIC INTO THE REAL WORLD...THAT`S LIKE SAYING...WE`RE GOING TO HAVE RAIN...BUT NO CLOUDS. IT DOESN`T MAKE SENSE. AS A RESULT...IT IS POSSIBLE THAT THE MODELS ARE SIMPLY PUTTING QPF OUT THERE BECAUSE THERE`S A BOUNDARY AND WE HAVE SOME MOISTURE AND CAPE IN PLACE SOUTH OF THE BOUNDARY. FOR MODELS THAT DO NOT SHOW MUCH ACTIVITY ALONG THE BOUNDARY THIS MORNING...THOSE SOLUTIONS REALLY RAMP UP THE CAPE AND MOISTURE POOLING SOUTH OF THIS BOUNDARY THIS AFTERNOON. THOSE MODELS INDICATE LOWER TO MID-70S DEW POINTS POOLING UP JUST SOUTH OF THE DFW AREA THIS AFTERNOON...RESULTING IN OVER 4000 J/KG OF CAPE. GRANTED...THERE IS VERY WEAK WIND SHEAR...SO EVEN IF STORMS DEVELOP IN THIS ENVIRONMENT THEY PROBABLY WILL NOT BE VERY ORGANIZED. THAT SAID...ANY STORMS THAT DEVELOP WITH 4000 J/KG OF CAPE WILL GET BIG...FAST. LOCALLY HEAVY RAINFALL AND MICROBURSTS WOULD BE THE PRIMARY HAZARDS IF THIS SCENARIO PANS OUT. ALSO...IF THUNDERSTORMS DO NOT DEVELOP THIS MORNING...THE BOUNDARY WILL PROBABLY MOVE A BIT WITH THE WESTERN PART OF THE BOUNDARY MOVING NORTH. IN THIS SCENARIO THE BOUNDARY WILL BE LOCATED NEAR A BOWIE TO GRAPEVINE TO EMORY LINE BEFORE THUNDERSTORMS ARE MOST LIKELY TO DEVELOP. WITH WATER VAPOR SATELLITE IMAGERY SHOWING A COUPLE OF WEAK SHORTWAVE TROUGHS OVER COLORADO AND NEW MEXICO EARLY THIS MORNING...WENT AHEAD AND BUMPED UP POPS A BIT FOR THIS AFTERNOON JUST IN CASE THIS SCENARIO PANS OUT. THIS FORECAST PROBLEM SHOULD AT LEAST BE FAIRLY EASY TO FIGURE OUT TODAY...IF WE END UP WITH SCATTERED STORMS ALONG THE BOUNDARY THAT PERSIST FOR AT LEAST A FEW HOURS THIS MORNING...WE HAVE A BETTER CHANCE AT WASHING OUT OUR BOUNDARY...MAKING AFTERNOON THUNDERSTORM CHANCES LESS LIKELY. IF THERE IS BRIEF OR NO THUNDERSTORM ACTIVITY ALONG THE BOUNDARY THIS MORNING...WE COULD SEE SOME SCATTERED STRONG STORMS DEVELOP ACROSS MUCH OF NORTH AND CENTRAL TEXAS THIS AFTERNOON. HAVE POPS IN THE 20 TO 50 PERCENT RANGE TODAY DUE TO UNCERTAINTY WITH REGARDS TO HOW TODAY WILL PLAY OUT. BY LATE THIS AFTERNOON...MOST MODELS HAVE THIS BOUNDARY GETTING WASHED OUT BY PERSISTENT SOUTHERLY FLOW AND STRONG DAYTIME HEATING. FOR TONIGHT...IF WE GET A LARGE CLUSTER OF STORMS TO PERSIST THIS AFTERNOON...WE COULD SEE SOME OF THIS ACTIVITY CONTINUE ACROSS THE CWA THROUGH THE OVERNIGHT HOURS. ANY LINGERING SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE MUCH WEAKER THAN THIS AFTERNOON. OTHERWISE...IF NOTHING GETS GOING THIS AFTERNOON...OUR ATTENTION THEN TURNS TO THE HIGH PLAINS WHERE HIGH RESOLUTION MODELS CONSISTENTLY SHOW A SQUALL LINE ORGANIZING LATE TONIGHT. IF THE SQUALL LINE BECOMES STRONG ENOUGH...IT WILL CREATE ITS OWN MINI- WEATHER SYSTEM THAT COULD PROPAGATE IT SOUTHEAST OVER NORTH TEXAS BY EARLY WEDNESDAY MORNING. CONFIDENCE IN THIS IS NOT AS GREAT AS IT WAS FOR YESTERDAY MORNING...MAINLY BECAUSE LOW-LEVEL SHEAR IS SOMEWHAT LACKING IN MOST MODEL SOLUTIONS. LOW-LEVEL WIND SHEAR IS ONE OF THE KEY FACTORS THAT HELPS BALANCE COLD-POOL STRENGTH AND REALLY HELPS LINEAR CONVECTIVE SYSTEMS BECOME ORGANIZED INTO THEIR OWN MINI-WEATHER SYSTEM. IN THE ABSENCE OF STRONGER LOW-LEVEL SHEAR...THESE STORM COMPLEXES STILL BECOME QUITE STRONG WHERE THEY ORIGINATE...BUT TEND TO LOSE THEIR COLD POOLS AND DISSIPATE WHEN THEY BEGIN TO PROPAGATE AWAY FROM THE HIGH PLAINS. BECAUSE OF THE LACK OF BETTER LOW-LEVEL SHEAR...ONLY WENT WITH 30 POPS FOR THIS POSSIBILITY FOR THE FAR NORTHWESTERN CWA EARLY WEDNESDAY MORNING. WEDNESDAY...MODELS ARE FAIRLY CONSISTENT IN BRINGING A SHORTWAVE TROUGH SOUTH ACROSS THE RED RIVER TOMORROW AFTERNOON. ASSUMING THIS PANS OUT...EXPECT SCATTERED THUNDERSTORMS TO DEVELOP NORTH OF INTERSTATE 20 TOMORROW AFTERNOON AND THEN MOVE SOUTHEAST IN THE WEAK NORTHWEST FLOW ALOFT. ALSO...MODELS ARE SHOWING A FAIRLY CONSISTENT SIGNAL OF A STRONGER THAN NORMAL SEA-BREEZE BOUNDARY MOVING NORTH FROM THE GULF COAST TOMORROW. AT LEAST THAT`S WHAT IT LOOKS LIKE IN THE MID-LEVEL RELATIVE HUMIDITY FIELDS. AT ANY RATE...WITH THE CONSISTENCY OF MODELS SHOWING QPF...WITH CLOUDS...MOVING IN FROM THE GULF COAST TOMORROW AFTERNOON...WENT AHEAD AND KEPT SOME HIGHER POPS OVER THE SOUTHEASTERN CWA. THURSDAY...MODELS CONTINUE TO SHOW THAT THE WEDNESDAY SHORTWAVE TROUGH WILL SORT OF MEANDER SOUTH AND JUST BECOME A GENERAL WEAKNESS ALOFT STUCK IN BETWEEN UPPER LEVEL RIDGES TO OUR WEST AND EAST. MODELS ARE SHOWING THAT THE WESTERN RIDGE WILL BEGIN TO AMPLIFY A BIT THURSDAY AFTERNOON...POSSIBLY SPREADING SOME FORCING FOR SUBSIDENCE OVER THE FAR WESTERN CWA. AS A RESULT...KEPT HIGHEST POP CHANCES FOR THURSDAY ALONG AND EAST OF INTERSTATE 35 AS THIS IS FURTHER REMOVED FROM THE RIDGE AND STILL WELL WITHIN THE MODEL CONSENSUS LOCATION OF THE COL/UPPER LEVEL WEAKNESS AREA. WE WILL STILL HAVE PLENTY OF MOISTURE WITH LITTLE CAP IN PLACE FOR AFTERNOON THUNDERSTORM CHANCES EAST OF INTERSTATE 35...SO KEPT POPS IN THE 30-40 PERCENT RANGE AT THIS TIME. FRIDAY THROUGH EARLY NEXT WEEK...THE GFS CONTINUES TO SHOW THAT A STRONG WEST COAST UPPER TROUGH WILL MOVE EASTWARDS OVER THE ROCKIES BY FRIDAY AFTERNOON. THE GFS HAS BEEN SHOWING THIS RESULTING IN LAYING THE NORTHERN MEXICO UPPER RIDGE OVER NORTH TEXAS BY FRIDAY...AND HOLDING IN PLACE THROUGH THE UPCOMING WEEKEND. THERE ARE STILL SOME MODEL SOLUTIONS THAT INDICATE THAT UPPER LEVEL RIDGING WILL STAY WEST RESULTING IN A PERSISTENT WEAKNESS ALOFT OVER PARTS OF THE AREA THIS WEEKEND...HOWEVER THE GFS HAS BEEN EXTREMELY CONSISTENT WITH THIS SOLUTION...AND AS RESULT WAS RELIED UPON HEAVILY IN THIS FORECAST. THE GFS HAS UPPER LEVEL RIDING IN PLACE OVER NORTH TEXAS FROM FRIDAY THROUGH THE MIDDLE OF NEXT WEEK...WITH RIDGING ONLY INCREASING IN INTENSITY EARLY NEXT WEEK. WENT WITH A DRY FORECAST FOR THE ENTIRE CWA DURING THIS PERIOD AS A RESULT. ALSO WENT AHEAD AND GRADUALLY RAISED TEMPERATURES THROUGH THIS PERIOD. IF THIS VERIFIES...WE MAY GET INTO OUR FIRST 100 DEGREE HIGHS HERE BY TUESDAY OR WEDNESDAY OF NEXT WEEK. THAT`S A LONG WAYS OUT OF COURSE...BUT THE PATTERN LOOKS HOT AND DRY FOR NOW. CAVANAUGH && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 92 75 93 75 91 / 40 40 40 20 30 WACO, TX 90 73 90 73 92 / 50 50 50 20 30 PARIS, TX 89 72 90 72 89 / 20 20 40 20 40 DENTON, TX 91 73 91 73 91 / 30 30 40 20 30 MCKINNEY, TX 92 74 92 74 91 / 30 30 40 20 40 DALLAS, TX 92 75 92 74 91 / 40 40 40 20 40 TERRELL, TX 93 76 93 76 92 / 40 40 30 20 40 CORSICANA, TX 89 73 90 73 91 / 50 50 50 20 40 TEMPLE, TX 91 72 90 73 90 / 50 50 50 20 30 MINERAL WELLS, TX 89 72 90 71 90 / 50 50 30 20 20 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ /
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1231 PM CDT TUE JUN 24 2014 .DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW. && .AVIATION...DEEPER MOISTURE TODAY VERSUS YESTERDAY HAS RESULTED IN INCREASED SHOWER AND EMBEDDED TSTORM COVERAGE. ENHANCED SEA BREEZE CONVECTION IS CURRENTLY BISECTING CAMERON COUNTY INTO WEST AND EAST HALVES...HAVING EARLIER AFFLICTED THE BROWNSVILLE AREA AND NOW MOVING OVER THE HRL ENVIRONS. SHOWERS WILL CONTINUE TO TRAIN NORTH OVER THE COASTAL COUNTIES...WITH DEVELOPMENT POSSIBLY MOVING UP FROM MEXICO OVER THE MID VALLEY AS WELL THIS AFTERNOON. THE RUC AND NAM SEEM TO AGREE ON THE BEST COVERAGE SHIFTING INLAND THIS AFTERNOON. RAIN CHANCES SHOULD AMELIORATE THIS EVENING WITH LOSS OF DAYTIME HEATING...WITH LIGHT TO MODERATE SOUTHEAST WINDS DECREASING TO LESS THAN 10 MPH...BUT A REPEAT OF UNSETTLED WEATHER WILL OCCUR ON WEDNESDAY. LOOK FOR BKN TO OVC VFR CEILINGS EXCEPT NEAR SCATTERED SHOWER AND TSTM ACTIVITY WHEN CEILINGS MAY DROP BELOW 3 KFT. && .PREV DISCUSSION... /ISSUED 652 AM CDT TUE JUN 24 2014/ DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW. AVIATION...A MIX OF LOW AND MID LEVEL CLOUDS PREVAIL ACROSS THE RIO GRANDE VALLEY AND DEEP SOUTH TEXAS THIS MORNING. EXPECT A MIX OF VFR/MVFR CONDITIONS TO PREVAIL THROUGH 14Z. WILL MENTION A TEMPO GROUP AT BRO DUE TO CEILINGS AT 800 FEET. WEAK 500 MB TROUGH/LOW ACROSS THE LOWER TEXAS COAST WILL CONTINUE TO PROVIDE VICINITY SHOWERS AFTER 15Z WITH A CHANCE OF MVFR CONDITIONS AS ISOLATED THUNDERSTORMS DEVELOPING THIS AFTERNOON. LIGHT SOUTHEAST WINDS WILL BECOME MODERATE BY 15Z. SOUTHEAST WINDS WILL DECREASE THIS EVENING WITH VFR CONDITIONS EXPECTED ACROSS THE REGION. MVFR CEILINGS MAY RETURN TO THE REGION AFTER 08Z BUT WILL NOT MENTION AT THIS TIME DUE TO LOW CONFIDENCE. PREV DISCUSSION... /ISSUED 402 AM CDT TUE JUN 24 2014/ SHORT TERM /NOW THROUGH WEDNESDAY/...UNSETTLED WEATHER WILL PREVAIL ACROSS THE RIO GRANDE VALLEY AND DEEP SOUTH TEXAS THROUGH THE PERIOD. THE REGION WILL CONTINUE TO BE UNDER AN AREA OF MID LEVEL WEAKNESS THROUGH MIDWEEK. THE INFLUX OF ABUNDANT TROPICAL MOISTURE ACROSS THE AREA COMBINED WITH DEEP ONSHORE FLOW AND WEAKNESS ALOFT WILL PROVIDE INCREASE RAIN CHANCES THROUGH WEDNESDAY. PRECIPITABLE WATER VALUES EXCEEDING 2 INCHES ACROSS THE REGION TODAY THROUGH WEDNESDAY COULD RESULT IN HEAVY RAINFALL IN SOME OF THE SLOWER MOVING SHOWERS AND STORMS. MODEL GUIDANCE CONTINUES TO SUPPORT ISOLATED TO SCATTERED POPS THROUGH THE PERIOD. WILL MAINTAIN LOW END SCATTERED POPS FOR TODAY WITH RAIN CHANCES DECREASING THIS EVENING AND OVERNIGHT WITH THE LOSS OF DAY TIME HEATING. WILL MENTION HIGH END SCATTERED POPS FOR WEDNESDAY WITH BETTER SEA BREEZE CONVECTION. THE INCREASE IN MOISTURE AND CLOUD COVER SHOULD KEEP HIGH TEMPERATURES ACROSS THE AREA IN THE UPPER 80S TO LOWER 90S NEAR THE COAST TO THE MID TO UPPER ACROSS THE WEST TODAY. OVERNIGHT LOW TEMPERATURES TONIGHT WILL BE IN THE MID TO UPPER 70S. HIGH TEMPERATURES ON WEDNESDAY SHOULD BE A DEGREE OR TWO LOWER THAN TODAY DUE TO BETTER RAIN CHANCES AND THICKER CLOUD COVER. LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...FORECAST PHILOSOPHY IN THE LONG TERM PORTION OF THE FORECAST REMAINS THE SAME. 500 MB TROUGHINESS OVER THE TEXAS COASTLINE WILL PERSIST BETWEEN A 500 MB HIGH CENTERED OVER THE WEST COAST OF THE BAJA PENINSULA AND THE FLORIDA STRAITS. WITH SURGES OF VERY DEEP TROPICAL MOISTURE...WITH PRECIPITABLE WATER VALUES BETWEEN 2 AND 2.3 INCHES...ENTERING DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY FROM THE BAY OF CAMPECHE... COMBINING WITH DAYTIME HEATING...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL RESULT. SIGNIFICANT CLOUD COVER ASSOCIATED WITH THE PRECIPITATION WILL HOLD TEMPERATURES TO NEAR NORMAL LEVELS. MARINE...NOW THROUGH WEDNESDAY...BUOY 42020 REPORTED SOUTH-SOUTHEAST WINDS AT 12 KNOTS WITH GUSTS OF 14 KNOTS AND SEAS OF 3.3 FEET AT 0750 UTC /0250 AM CDT. THE LATEST OBSERVATION PLATFORMS ACROSS THE LAGUNA MADRE INDICATES SOUTHEAST WINDS BETWEEN 9 TO 13 KNOTS. BROAD HIGH PRESSURE OVER THE GULF WILL INTERACT WITH LOWER PRESSURE ACROSS THE SOUTHWESTERN GULF AND THE CENTRAL PLAIN STATES THROUGH MIDWEEK. THE PRESSURE GRADIENT WILL MAINTAIN LIGHT TO MODERATE SOUTHEAST TO SOUTH WINDS AND LOW TO MODERATE SEAS THROUGH WEDNESDAY. SMALL CRAFT EXERCISE CAUTION CONDITIONS POSSIBLE BY WEDNESDAY AFTERNOON DUE TO INCREASING WINDS AND SEAS. THE LATEST NAM/GFS AND ECMWF SOLUTIONS NO LONGER SUPPORTS LOW END SMALL CRAFT ADVISORY CONDITIONS OVER THE LOWER TEXAS GULF WATERS. SO HAVE LOWERED WINDS AND SEAS DOWN THROUGH THE FORECAST PERIOD. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE COASTAL WATERS THROUGH THE PERIOD AS MID LEVEL WEAKNESS PERSISTS OVERHEAD. WEDNESDAY NIGHT THROUGH MONDAY...HIGH PRESSURE CENTERED OFF THE COAST OF LOUISIANA WILL INTERACT WITH PERSISTENT LOW PRESSURE OVER THE TEXAS PANHANDLE AND WEST TEXAS...PRODUCING WINDS AND SEAS THAT WILL BE MORE INDICATIVE OF SMALL CRAFT EXERCISE CAUTION EARLY IN THE FORECAST PERIOD. AS THE INTERACTION BETWEEN THESE SYSTEMS INTENSIFIES...WINDS AND SEAS WILL INCREASE SLIGHTLY...SUCH THAT SMALL CRAFT ADVISORIES ALONG THE LOWER TEXAS COAST WILL BE MORE LIKELY FRIDAY NIGHT AND INTO EARLY NEXT WEEK. && .BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV 54/53
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1125 AM CDT TUE JUN 24 2014 .UPDATE... ASIDE FROM A FEW ISOLATED SHOWERS/STORMS ACROSS THE SOUTHEASTERN QUADRANT OF THE CWA...MOST OF THE STORM ACTIVITY IS TO OUR WEST ACROSS THE TEXAS PANHANDLE AND WEST TEXAS. REGARDING RAIN/STORM POTENTIAL FOR THE REMAINDER OF THE DAY...OUR POTENTIAL FOCUSES ON TWO DIFFERENT AREAS. THE FIRST IS A BOUNDARY THAT CURRENTLY LIES ALONG A LINE FROM EMORY TO DFW TO SOUTH OF GRAHAM. THE WINDS NORTH OF THE BOUNDARY ARE FROM THE SOUTHEAST WHILE THE WINDS SOUTH OF THE BOUNDARY ARE FROM THE SOUTH. HOWEVER...DEWPOINTS ACROSS THE BOUNDARY VARY MORE MAKING THE IDENTIFICATION OF THE BOUNDARY EASIER IN THAT REGARD. DEWPOINTS NORTH OF THE BOUNDARY ARE IN THE UPPER 60S WITH 70S SOUTH OF THE BOUNDARY. THE WINDS IN THE METROPLEX HAVE BECOME MORE SOUTHERLY THIS HOUR WITH DEWPOINTS INCREASING TO AROUND 70 SUGGESTING MAYBE THIS BOUNDARY IS LIFTING NORTH SOME. AS TEMPERATURES WARM SOUTH OF THE BOUNDARY INTO THE UPPER 80S/NEAR 90 DEGREES THIS AFTERNOON...CAPE VALUES WILL INCREASE WITH VALUES UP TO 4000 J/KG IN SOME LOCATIONS. WIND SHEAR VALUES WILL BE LOW...GENERALLY LESS THAN 15 MPH...AND AS DESCRIBED IN THIS MORNINGS DISCUSSION...STORMS THIS AFTERNOON COULD QUICKLY BECOME STRONG/SEVERE BUT WILL LIKELY NOT BE ORGANIZED DUE TO THE WEAK SHEAR. HOWEVER...THESE STORMS WILL HAVE A THREAT FOR DAMAGING MICROBURST WINDS...FREQUENT LIGHTNING...AND HEAVY RAINFALL. THE HEAVY RAINFALL MAY RESULT IN NUISANCE FLOODING OR FLASH FLOODING AS STORM MOTIONS WILL BE SLOW AT SPEEDS LESS THAN 10-15 MPH. NEW STORM DEVELOPMENT WILL ALSO BE POSSIBLE ON ANY OUTFLOW BOUNDARIES FROM THIS AFTERNOONS STORMS WHICH COULD INCREASE A LOCALIZED FLASH FLOODING THREAT. THE SECOND AREA OF CONCERN FOR THUNDERSTORMS THIS AFTERNOON IS ASSOCIATED WITH THE COMPLEX OF STORMS CURRENTLY IN THE TEXAS PANHANDLE TO THE EAST OF LUBBOCK. THIS COMPLEX IS RIDING ITS OUTFLOW BOUNDARY AND QUICKLY MOVING SOUTHEAST. WE ANTICIPATE THIS MCS TO REACH OUR WESTERN COUNTIES LATER THIS AFTERNOON OR EARLY EVENING. DESPITE THE WEAK LOW LEVEL WIND FLOW INTO THIS SYSTEM...IT IS LIKELY TO MAINTAIN ITS COMPOSURE ENOUGH TO REACH THE CWA BASED ON ITS COLD POOL INTERACTIONS. IN ADDITION...THE MCS IS HEADING INTO A MORE HUMID AND UNSTABLE ENVIRONMENT ACROSS NORTHWEST AND NORTH TEXAS WHICH WOULD FAVOR ITS MAINTENANCE LONG ENOUGH TO REACH NORTH/CENTRAL TEXAS. WHEN THE COMPLEX REACHES OUR COUNTIES IT COULD BE SEVERE WITH A DAMAGING WIND...HEAVY RAIN...AND POSSIBLY HAIL THREAT. IN ADDITION...STORMS ARE DEVELOPING AHEAD OF THE COMPLEX ACROSS AREAS NORTHWEST OF ABILENE. THIS SUPPORTS AN UNSTABLE ENVIRONMENT ACROSS THE WESTERN PORTIONS OF THE REGION. THESE NEW STORMS ARE NOT MOVING VERY FAST AND WILL LIKELY BE ABSORBED BY THE MCS. FOR THE UPDATE...INCREASED POPS ACROSS THE WEST FOR THE REMAINDER OF THE DAY AND EVENING WITH 50 POPS ACROSS THE WEST AND SOUTH HALVES OF THE CWA. DID NOT ADJUST TEMPERATURES MUCH...BUT HIGH CLOUD DEBRIS AND AREAS OF RAIN WILL LIKELY KEEP TEMPERATURES A FEW DEGREES COOLER IN SOME LOCATIONS. 82/JLD && .AVIATION... /ISSUED 613 AM CDT TUE JUN 24 2014/ SHOWERS HAVE DEVELOPED NEAR A SURFACE BOUNDARY LOCATED BETWEEN THE DALLAS-FORT WORTH METROPLEX AND THE WACO/TEMPLE/KILLEEN AREA. THE LATEST ANALYSIS INDICATES AN AXIS OF INSTABILITY LOCATED ALONG THIS BOUNDARY WITH MLCAPE AROUND 1000 J/KG...WHICH SHOULD ALLOW FOR OCCASIONAL THUNDERSTORMS THIS MORNING. STORMS WILL LIKELY OCCUR BETWEEN THE METROPLEX AND WACO WITH CELL MOVEMENT DUE EAST...SO DIRECT IMPACT AT ANY OF THE TERMINALS APPEARS FARLY SLIM FOR THE TIME BEING. BETTER CHANCES FOR CONVECTION ARRIVE LATER THIS AFTERNOON AS A SHORTWAVE CURRENTLY OVER WEST-CENTRAL TEXAS SLOWLY WORKS ITS WAY EAST. LARGE DISCREPANCIES EXIST BETWEEN VARIOUS COMPUTER MODELS WITH REGARD TO TIMING OF CONVECTION LATER TODAY. AM LEANING CLOSE TO THE NAM12 SOLUTION FOR ONSET OF CONVECTION AT AREA TERMINALS BECAUSE IT SEAMS TO HAVE THE BEST HANDLE ON THE CURRENT FEATURES AND ASSOCIATED CONVECTION. WILL INTRODUCE VCTS AT ALL TERMINALS AROUND 22-00Z THIS EVENING AND FINE TUNE THE TIMING IN LATER FORECASTS IF IT BECOMES NECESSARY. 30 && .PREV DISCUSSION... /ISSUED 411 AM CDT TUE JUN 24 2014/ 08Z/3AM SURFACE ANALYSIS SHOWED A STATIONARY BOUNDARY IN PLACE FROM SULPHUR SPRINGS TO BURLESON TO BRECKENRIDGE. THERE WERE WEAK GRADIENTS OF BOTH TEMPERATURE AND DEW POINT ALONG THE BOUNDARY WITH COOLER VALUES LOCATED NORTH OF THE BOUNDARY. LOOKING AT THE GRADIENT OF EITHER TEMPERATURE OR DEW POINT ALONG THIS BOUNDARY IS NOT VERY IMPRESSIVE...HOWEVER...OBJECTIVE ANALYSIS INDICATES THAT THIS RESULTS IN A FAIRLY TIGHT GRADIENT OF THETA-E WITH A CHANGE OF ALMOST 8 KELVIN FROM NORTH TO SOUTH ALONG THIS BOUNDARY. AS A RESULT...THINK THAT THIS BOUNDARY WILL HANG AROUND THROUGH AT LEAST THE MORNING HOURS OF THE DAY TODAY. IT MAY HOLD SOME IDENTITY INTO THE AFTERNOON HOURS AS WELL IF SHORT RANGE MODEL GUIDANCE IS ACCURATE. THE 07Z RAP INDICATED THAT THIS BOUNDARY EXTENDS UP TO THE 850 MB LEVEL WHERE THE THETA-E GRADIENT IS EVEN MORE PRONOUNCED...SHOWING A THETA-E CHANGE OF 12-16 KELVIN ALONG THE BOUNDARY THROUGH THIS MORNING. THE MAIN POINT OF THIS ANALYSIS IS THAT THIS BOUNDARY APPEARS AS THROUGH IT IS STRONG ENOUGH TO REMAIN SOMEWHERE IN THE CWA AS WE APPROACH THE PEAK HEATING HOURS OF THE DAY. IF IT STILL EXISTS THIS AFTERNOON...IT COULD BE A BIG PLAYER IN THUNDERSTORM INITIATION TODAY. REGARDING THUNDERSTORM CHANCES FOR TODAY...ALMOST ALL GUIDANCE INDICATES THAT THIS BOUNDARY IS IMPORTANT FOR THUNDERSTORM CHANCES TODAY AS MOST GUIDANCE ADVERTISES QPF ALONG THIS BOUNDARY SOMETIME THIS MORNING THROUGH THIS AFTERNOON. THE TIMING OF WHEN THIS QPF SHOWS UP IS THE KEY DIFFERENCE AMONGST THE MODELS. MANY OF THE HIGH-RESOLUTION MODELS SHOW QPF OR SIMULATED REFLECTIVITY DEVELOPING ALONG THIS BOUNDARY JUST AFTER SUNRISE THIS MORNING. IF THIS OCCURS...THE CONVECTION THAT IS INITIATED WILL PROBABLY BE RELATIVELY WEAK IN NATURE AND MAY BE SOMEWHAT ELEVATED AS MOSTLY CLEAR SKIES TONIGHT OVER THE BOUNDARY HAS ALLOWED A NICE NOCTURNAL INVERSION TO SET UP OVER THE AREA. IT`S HARD TO SAY WHETHER THIS CONVECTION WOULD BE ENOUGH TO IMPACT THE BOUNDARY OR NOT IF IT DEVELOPS THIS MORNING. IF NOTHING ELSE...IT WILL ADD CLOUDS OVER THE WARMER SIDE OF THE BOUNDARY ALLOWING DIFFERENTIAL HEATING TO REDUCE THE IDENTITY OF THE BOUNDARY BY WARMING THE COOL SIDE AND KEEPING THE WARM SIDE SHIELDED FROM SUNSHINE/HEATING. IT`S PROBABLY FOR THIS REASON THAT MOST HIGH RESOLUTION GUIDANCE MEMBERS HAVE MORNING CONVECTION ALONG AND SOUTH OF THIS BOUNDARY WITH LITTLE TO NO ADDITIONAL PRECIPITATION THIS AFTERNOON. IF THERE IS LITTLE TO NO ACTIVITY ALONG THE BOUNDARY THIS MORNING...THIS BOUNDARY PROBABLY HAS A BETTER CHANCE AT INITIATING STRONG THUNDERSTORMS ACROSS NORTH OR CENTRAL TEXAS THIS AFTERNOON. HIGH RESOLUTION GUIDANCE IS USUALLY FAIRLY RELIABLE WHEN CONSISTENTLY SHOWING A SIMULATED REFLECTIVITY SIGNAL OF THUNDERSTORM INITIATION ALONG A COMMON BOUNDARY AROUND A COMMON TIME. THEREFORE...THERE MAY BE A SLIGHTLY BETTER CHANCE THAT STORMS DEVELOP ALONG THE BOUNDARY THIS MORNING RATHER THAN HOLDING OFF UNTIL THIS AFTERNOON. THE ONLY REASON TO DOUBT SOME OF THE MODELS SHOWING THIS MORNING CONVECTION IS THE LACK OF RESPONSE IN THE REST OF THE MASS FIELDS WHERE THE QPF IS LOCATED. THAT IS...SOME POSITIVE QPF SHOWS UP SOUTH OF THE BOUNDARY...THIS SEEMS TO MAKE SENSE...HOWEVER THERE IS NO INCREASE IN MID-LEVEL RELATIVE HUMIDITY AND NO LOW-LEVEL RESPONSE IN THE WIND FIELDS. BRINGING MODEL LOGIC INTO THE REAL WORLD...THAT`S LIKE SAYING...WE`RE GOING TO HAVE RAIN...BUT NO CLOUDS. IT DOESN`T MAKE SENSE. AS A RESULT...IT IS POSSIBLE THAT THE MODELS ARE SIMPLY PUTTING QPF OUT THERE BECAUSE THERE`S A BOUNDARY AND WE HAVE SOME MOISTURE AND CAPE IN PLACE SOUTH OF THE BOUNDARY. FOR MODELS THAT DO NOT SHOW MUCH ACTIVITY ALONG THE BOUNDARY THIS MORNING...THOSE SOLUTIONS REALLY RAMP UP THE CAPE AND MOISTURE POOLING SOUTH OF THIS BOUNDARY THIS AFTERNOON. THOSE MODELS INDICATE LOWER TO MID-70S DEW POINTS POOLING UP JUST SOUTH OF THE DFW AREA THIS AFTERNOON...RESULTING IN OVER 4000 J/KG OF CAPE. GRANTED...THERE IS VERY WEAK WIND SHEAR...SO EVEN IF STORMS DEVELOP IN THIS ENVIRONMENT THEY PROBABLY WILL NOT BE VERY ORGANIZED. THAT SAID...ANY STORMS THAT DEVELOP WITH 4000 J/KG OF CAPE WILL GET BIG...FAST. LOCALLY HEAVY RAINFALL AND MICROBURSTS WOULD BE THE PRIMARY HAZARDS IF THIS SCENARIO PANS OUT. ALSO...IF THUNDERSTORMS DO NOT DEVELOP THIS MORNING...THE BOUNDARY WILL PROBABLY MOVE A BIT WITH THE WESTERN PART OF THE BOUNDARY MOVING NORTH. IN THIS SCENARIO THE BOUNDARY WILL BE LOCATED NEAR A BOWIE TO GRAPEVINE TO EMORY LINE BEFORE THUNDERSTORMS ARE MOST LIKELY TO DEVELOP. WITH WATER VAPOR SATELLITE IMAGERY SHOWING A COUPLE OF WEAK SHORTWAVE TROUGHS OVER COLORADO AND NEW MEXICO EARLY THIS MORNING...WENT AHEAD AND BUMPED UP POPS A BIT FOR THIS AFTERNOON JUST IN CASE THIS SCENARIO PANS OUT. THIS FORECAST PROBLEM SHOULD AT LEAST BE FAIRLY EASY TO FIGURE OUT TODAY...IF WE END UP WITH SCATTERED STORMS ALONG THE BOUNDARY THAT PERSIST FOR AT LEAST A FEW HOURS THIS MORNING...WE HAVE A BETTER CHANCE AT WASHING OUT OUR BOUNDARY...MAKING AFTERNOON THUNDERSTORM CHANCES LESS LIKELY. IF THERE IS BRIEF OR NO THUNDERSTORM ACTIVITY ALONG THE BOUNDARY THIS MORNING...WE COULD SEE SOME SCATTERED STRONG STORMS DEVELOP ACROSS MUCH OF NORTH AND CENTRAL TEXAS THIS AFTERNOON. HAVE POPS IN THE 20 TO 50 PERCENT RANGE TODAY DUE TO UNCERTAINTY WITH REGARDS TO HOW TODAY WILL PLAY OUT. BY LATE THIS AFTERNOON...MOST MODELS HAVE THIS BOUNDARY GETTING WASHED OUT BY PERSISTENT SOUTHERLY FLOW AND STRONG DAYTIME HEATING. FOR TONIGHT...IF WE GET A LARGE CLUSTER OF STORMS TO PERSIST THIS AFTERNOON...WE COULD SEE SOME OF THIS ACTIVITY CONTINUE ACROSS THE CWA THROUGH THE OVERNIGHT HOURS. ANY LINGERING SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE MUCH WEAKER THAN THIS AFTERNOON. OTHERWISE...IF NOTHING GETS GOING THIS AFTERNOON...OUR ATTENTION THEN TURNS TO THE HIGH PLAINS WHERE HIGH RESOLUTION MODELS CONSISTENTLY SHOW A SQUALL LINE ORGANIZING LATE TONIGHT. IF THE SQUALL LINE BECOMES STRONG ENOUGH...IT WILL CREATE ITS OWN MINI- WEATHER SYSTEM THAT COULD PROPAGATE IT SOUTHEAST OVER NORTH TEXAS BY EARLY WEDNESDAY MORNING. CONFIDENCE IN THIS IS NOT AS GREAT AS IT WAS FOR YESTERDAY MORNING...MAINLY BECAUSE LOW-LEVEL SHEAR IS SOMEWHAT LACKING IN MOST MODEL SOLUTIONS. LOW-LEVEL WIND SHEAR IS ONE OF THE KEY FACTORS THAT HELPS BALANCE COLD-POOL STRENGTH AND REALLY HELPS LINEAR CONVECTIVE SYSTEMS BECOME ORGANIZED INTO THEIR OWN MINI-WEATHER SYSTEM. IN THE ABSENCE OF STRONGER LOW-LEVEL SHEAR...THESE STORM COMPLEXES STILL BECOME QUITE STRONG WHERE THEY ORIGINATE...BUT TEND TO LOSE THEIR COLD POOLS AND DISSIPATE WHEN THEY BEGIN TO PROPAGATE AWAY FROM THE HIGH PLAINS. BECAUSE OF THE LACK OF BETTER LOW-LEVEL SHEAR...ONLY WENT WITH 30 POPS FOR THIS POSSIBILITY FOR THE FAR NORTHWESTERN CWA EARLY WEDNESDAY MORNING. WEDNESDAY...MODELS ARE FAIRLY CONSISTENT IN BRINGING A SHORTWAVE TROUGH SOUTH ACROSS THE RED RIVER TOMORROW AFTERNOON. ASSUMING THIS PANS OUT...EXPECT SCATTERED THUNDERSTORMS TO DEVELOP NORTH OF INTERSTATE 20 TOMORROW AFTERNOON AND THEN MOVE SOUTHEAST IN THE WEAK NORTHWEST FLOW ALOFT. ALSO...MODELS ARE SHOWING A FAIRLY CONSISTENT SIGNAL OF A STRONGER THAN NORMAL SEA-BREEZE BOUNDARY MOVING NORTH FROM THE GULF COAST TOMORROW. AT LEAST THAT`S WHAT IT LOOKS LIKE IN THE MID-LEVEL RELATIVE HUMIDITY FIELDS. AT ANY RATE...WITH THE CONSISTENCY OF MODELS SHOWING QPF...WITH CLOUDS...MOVING IN FROM THE GULF COAST TOMORROW AFTERNOON...WENT AHEAD AND KEPT SOME HIGHER POPS OVER THE SOUTHEASTERN CWA. THURSDAY...MODELS CONTINUE TO SHOW THAT THE WEDNESDAY SHORTWAVE TROUGH WILL SORT OF MEANDER SOUTH AND JUST BECOME A GENERAL WEAKNESS ALOFT STUCK IN BETWEEN UPPER LEVEL RIDGES TO OUR WEST AND EAST. MODELS ARE SHOWING THAT THE WESTERN RIDGE WILL BEGIN TO AMPLIFY A BIT THURSDAY AFTERNOON...POSSIBLY SPREADING SOME FORCING FOR SUBSIDENCE OVER THE FAR WESTERN CWA. AS A RESULT...KEPT HIGHEST POP CHANCES FOR THURSDAY ALONG AND EAST OF INTERSTATE 35 AS THIS IS FURTHER REMOVED FROM THE RIDGE AND STILL WELL WITHIN THE MODEL CONSENSUS LOCATION OF THE COL/UPPER LEVEL WEAKNESS AREA. WE WILL STILL HAVE PLENTY OF MOISTURE WITH LITTLE CAP IN PLACE FOR AFTERNOON THUNDERSTORM CHANCES EAST OF INTERSTATE 35...SO KEPT POPS IN THE 30-40 PERCENT RANGE AT THIS TIME. FRIDAY THROUGH EARLY NEXT WEEK...THE GFS CONTINUES TO SHOW THAT A STRONG WEST COAST UPPER TROUGH WILL MOVE EASTWARDS OVER THE ROCKIES BY FRIDAY AFTERNOON. THE GFS HAS BEEN SHOWING THIS RESULTING IN LAYING THE NORTHERN MEXICO UPPER RIDGE OVER NORTH TEXAS BY FRIDAY...AND HOLDING IN PLACE THROUGH THE UPCOMING WEEKEND. THERE ARE STILL SOME MODEL SOLUTIONS THAT INDICATE THAT UPPER LEVEL RIDGING WILL STAY WEST RESULTING IN A PERSISTENT WEAKNESS ALOFT OVER PARTS OF THE AREA THIS WEEKEND...HOWEVER THE GFS HAS BEEN EXTREMELY CONSISTENT WITH THIS SOLUTION...AND AS RESULT WAS RELIED UPON HEAVILY IN THIS FORECAST. THE GFS HAS UPPER LEVEL RIDING IN PLACE OVER NORTH TEXAS FROM FRIDAY THROUGH THE MIDDLE OF NEXT WEEK...WITH RIDGING ONLY INCREASING IN INTENSITY EARLY NEXT WEEK. WENT WITH A DRY FORECAST FOR THE ENTIRE CWA DURING THIS PERIOD AS A RESULT. ALSO WENT AHEAD AND GRADUALLY RAISED TEMPERATURES THROUGH THIS PERIOD. IF THIS VERIFIES...WE MAY GET INTO OUR FIRST 100 DEGREE HIGHS HERE BY TUESDAY OR WEDNESDAY OF NEXT WEEK. THAT`S A LONG WAYS OUT OF COURSE...BUT THE PATTERN LOOKS HOT AND DRY FOR NOW. CAVANAUGH && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 92 75 93 75 91 / 40 40 40 20 30 WACO, TX 90 73 90 73 92 / 50 50 50 20 30 PARIS, TX 89 72 90 72 89 / 20 20 40 20 40 DENTON, TX 91 73 91 73 91 / 30 30 40 20 30 MCKINNEY, TX 92 74 92 74 91 / 30 30 40 20 40 DALLAS, TX 92 75 92 74 91 / 40 40 40 20 40 TERRELL, TX 93 76 93 76 92 / 40 40 30 20 40 CORSICANA, TX 89 73 90 73 91 / 50 50 50 20 40 TEMPLE, TX 91 72 90 73 90 / 50 50 50 20 30 MINERAL WELLS, TX 89 72 90 71 90 / 50 50 30 20 20 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 92/82
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1156 AM MDT TUE JUN 24 2014 .UPDATE... ISSUED AT 1115 AM MDT TUE JUN 24 2014 NO MAJOR CHANGES TO THE GOING FORECAST THIS MORNING. WIDELY SCATTERED CONVECTION OVER PORTIONS OF THE PLAINS CONTINUES TO WEAKEN. EXPECT REDEVELOPMENT OF SHOWERS AND TSTORMS EARLY THIS AFTERNOON OVER THE LARAMIE RANGE THEN SPREADING EAST ONTO THE PLAINS FROM MID TO LATE AFTERNOON. WEAK SURFACE BOUNDARY REMAINS STATIONARY ALONG THE LARAMIE RANGE SEPARATING DEW POINTS IN THE 30S AND 40S WEST FROM THE 50S EAST. LATEST HRRR RADAR REFLECTIVITY PROGS SHOWS MORE INTENSE CONVECTION FORMING ALONG THE CHEYENNE BETWEEN 2 AND 4 PM THEN DRIFTING SOUTHEAST INTO NORTHEAST CO. WEAKER TSTORM ACTIVITY DEVELOPS WEST OF THE LARAMIE RANGE WHERE LESS LOW LEVEL MOISTURE RESIDES. BASED ON SPC/S DAY ONE OUTLOOK...MENTIONED RISK OF SEVERE FROM THE SOUTHERN LARAMIE RANGE EAST THROUGH CHEYENNE AND KIMBALL. WILL BE MONITORING RADAR TRENDS CLOSELY THIS AFTERNOON. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 224 AM MDT TUE JUN 24 2014 SOME CONVECTION CONTINUING ACROSS NORTHERN PARTS OF THE CWA INTO THE NEB PANHANDLE EARLY THIS MORNING AS WEAK IMPULSES MOVE BY IN WNW UPPER FLOW. SHOULD SEE THIS CONTINUE A LITTLE LONGER THIS MORNING BEFORE EBBING SOMEWHAT. SHOWERS AND TSTRMS SHOULD THEN RE-FIRE EARLY THIS AFTERNOON OVER THE MTNS AND PROCEED EASTWARD THROUGH THIS EVENING. A FEW STRONG STORMS POSSIBLE THOUGH UPPER WINDS A BIT LESS TODAY THUS A BIT LESS SHEAR. ACTIVITY WILL END LATER THIS EVENING WITH GENERALLY DRY WEATHER LATER TONIGHT. PATCHY FOG MAY DEVELOP BY EARLY WEDS MORNING OVER PARTS OF THE PLAINS ESPECIALLY WHERE ANY BETTER RAINS OCCUR. LITTLE CHANGE SEEN FOR WEDNESDAY AS SFC FRONT REMAINS BANKED UP AGAINST THE MTNS. A BIT BETTER SHEAR MAY ALLOW FOR STRONGER STORM ACTIVITY OVER THE PLAINS HOWEVER WITH INSTABILITY A BIT HIGHER GIVEN WARMER TEMPS. CONVECTION MIGHT HANG ON OVER THE NORTHERN PANHANDLE WEDS NIGHT. THURSDAY LOOKING PRETTY MUCH A REPEAT OF WEDS WITH WARM TEMPS AND WDLY SCTD AFTERNOON AND EVENING THUNDERSTORMS...SOME POSSIBLY STRONG OR SEVERE ONCE AGAIN. SFC FRONT WILL BEGIN TO EDGE EAST AND SHOULD HELP TO FOCUS CONVECTION. .LONG TERM...(THURSDAY NIGHT THROUGH MONDAY) ISSUED AT 224 AM MDT TUE JUN 24 2014 FRONTAL BOUNDARY REMAINS JUST TO THE EAST OF THE PANHANDLE THURSDAY NIGHT. KEPT SOME SLIGHT CHANCE TO LOW END CHANCE POPS GOING FOR THE PANHANDLE THURSDAY NIGHT. NEW ECMWF RUN CONTINUES TO SHOW ANOTHER SHORTWAVE MOVING INTO WESTERN WYOMING FRIDAY WITH INCREASING CHANCES FOR SHOWERS/THUNDERSTORMS OUT WEST. LATEST GFS RUN KEEPS THESE SHOWERS NORTH ACROSS NORTHERN WYOMING. ECMWF SEEMS REASONABLE AND USED IT FOR POPS FRIDAY. SHORTWAVE MOVES INTO EASTERN PORTIONS OF THE CWFA FRIDAY AFTERNOON FOR MORE WIDESPREAD CONVECTION. ECMWF SHOWING SOME PRETTY HEFTY QPF OUT IN THE PANHANDLE FRIDAY AFTERNOON WITH OVER A HALF INCH. IF THIS CONTINUES...WILL UNDOUBTEDLY HAVE TO RAISE POPS MORE THAN WHAT I HAVE IN THERE RIGHT NOW. SHORTWAVE CLEARS THE AREA TO THE EAST FRIDAY NIGHT...FORCING THE FRONTAL SYSTEM EAST AS WELL. BOTH THE GFS AND ECMWF DO HAVE SOME CONVECTION OVER NORTHERN WYOMING SATURDAY AFTERNOON THAT COULD SPILL INTO OUR NORTHERN ZONES...SO DO HAVE SOME SLIGHT CHANCE POPS GOING UP THAT WAY. DRY PATTERN FOR SUNDAY ON INTO THE REST OF THE EXTENDED AS SHORTWAVES TRACK ACROSS MONTANA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY MORNING) ISSUED AT 1147 AM MDT TUE JUN 24 2014 SCATTERED SHOWERS AND TSTMS WILL DEVELOP ONCE AGAIN AROUND 20Z THIS AFTN ALONG THE SOUTHERN LARAMIE RANGE. THESE STORMS WILL THEN MOVE EASTWARD...WITH THE COVERAGE HIGHEST IN AREAS NEAR INTERSTATE 80. INCLUDED VCTS AT MANY OF THE SITES EVEN THOUGH THE BEST CHANCE OF STORMS WILL STRETCH FROM LAR TO SNY. WINDS WILL GENERALLY BE LESS THAN 15 KTS OUTSIDE OF GUSTY WINDS FROM THE TSTMS. SHOWER ACTIVITY WILL DECREASE AFTER AROUND 06Z. && .FIRE WEATHER... ISSUED AT 224 AM MDT TUE JUN 24 2014 CONCERNS TO REMAIN LOW OVERALL THIS WEEK WITH MANY AREAS SEEING SOME RAIN AT ONE TIME OR ANOTHER. DRIEST AREAS WILL BE OVER FAR WESTERN DISTRICTS WITH MIN RHS LOWERING TO 10 TO 15 PERCENT. WINDS SHOULD NOT BE MUCH OF A FACTOR HOWEVER. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...JAMSKI SHORT TERM...RE LONG TERM...CLAYCOMB AVIATION...FINCH FIRE WEATHER...RE
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1117 AM MDT TUE JUN 24 2014 .UPDATE... ISSUED AT 1115 AM MDT TUE JUN 24 2014 NO MAJOR CHANGES TO THE GOING FORECAST THIS MORNING. WIDELY SCATTERED CONVECTION OVER PORTIONS OF THE PLAINS CONTINUES TO WEAKEN. EXPECT REDEVELOPMENT OF SHOWERS AND TSTORMS EARLY THIS AFTERNOON OVER THE LARAMIE RANGE THEN SPREADING EAST ONTO THE PLAINS FROM MID TO LATE AFTERNOON. WEAK SURFACE BOUNDARY REMAINS STATIONARY ALONG THE LARAMIE RANGE SEPARATING DEW POINTS IN THE 30S AND 40S WEST FROM THE 50S EAST. LATEST HRRR RADAR REFLECTIVITY PROGS SHOWS MORE INTENSE CONVECTION FORMING ALONG THE CHEYENNE BETWEEN 2 AND 4 PM THEN DRIFTING SOUTHEAST INTO NORTHEAST CO. WEAKER TSTORM ACTIVITY DEVELOPS WEST OF THE LARAMIE RANGE WHERE LESS LOW LEVEL MOISTURE RESIDES. BASED ON SPC/S DAY ONE OUTLOOK...MENTIONED RISK OF SEVERE FROM THE SOUTHERN LARAMIE RANGE EAST THROUGH CHEYENNE AND KIMBALL. WILL BE MONITORING RADAR TRENDS CLOSELY THIS AFTERNOON. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 224 AM MDT TUE JUN 24 2014 SOME CONVECTION CONTINUING ACROSS NORTHERN PARTS OF THE CWA INTO THE NEB PANHANDLE EARLY THIS MORNING AS WEAK IMPULSES MOVE BY IN WNW UPPER FLOW. SHOULD SEE THIS CONTINUE A LITTLE LONGER THIS MORNING BEFORE EBBING SOMEWHAT. SHOWERS AND TSTRMS SHOULD THEN RE-FIRE EARLY THIS AFTERNOON OVER THE MTNS AND PROCEED EASTWARD THROUGH THIS EVENING. A FEW STRONG STORMS POSSIBLE THOUGH UPPER WINDS A BIT LESS TODAY THUS A BIT LESS SHEAR. ACTIVITY WILL END LATER THIS EVENING WITH GENERALLY DRY WEATHER LATER TONIGHT. PATCHY FOG MAY DEVELOP BY EARLY WEDS MORNING OVER PARTS OF THE PLAINS ESPECIALLY WHERE ANY BETTER RAINS OCCUR. LITTLE CHANGE SEEN FOR WEDNESDAY AS SFC FRONT REMAINS BANKED UP AGAINST THE MTNS. A BIT BETTER SHEAR MAY ALLOW FOR STRONGER STORM ACTIVITY OVER THE PLAINS HOWEVER WITH INSTABILITY A BIT HIGHER GIVEN WARMER TEMPS. CONVECTION MIGHT HANG ON OVER THE NORTHERN PANHANDLE WEDS NIGHT. THURSDAY LOOKING PRETTY MUCH A REPEAT OF WEDS WITH WARM TEMPS AND WDLY SCTD AFTERNOON AND EVENING THUNDERSTORMS...SOME POSSIBLY STRONG OR SEVERE ONCE AGAIN. SFC FRONT WILL BEGIN TO EDGE EAST AND SHOULD HELP TO FOCUS CONVECTION. .LONG TERM...(THURSDAY NIGHT THROUGH MONDAY) ISSUED AT 224 AM MDT TUE JUN 24 2014 FRONTAL BOUNDARY REMAINS JUST TO THE EAST OF THE PANHANDLE THURSDAY NIGHT. KEPT SOME SLIGHT CHANCE TO LOW END CHANCE POPS GOING FOR THE PANHANDLE THURSDAY NIGHT. NEW ECMWF RUN CONTINUES TO SHOW ANOTHER SHORTWAVE MOVING INTO WESTERN WYOMING FRIDAY WITH INCREASING CHANCES FOR SHOWERS/THUNDERSTORMS OUT WEST. LATEST GFS RUN KEEPS THESE SHOWERS NORTH ACROSS NORTHERN WYOMING. ECMWF SEEMS REASONABLE AND USED IT FOR POPS FRIDAY. SHORTWAVE MOVES INTO EASTERN PORTIONS OF THE CWFA FRIDAY AFTERNOON FOR MORE WIDESPREAD CONVECTION. ECMWF SHOWING SOME PRETTY HEFTY QPF OUT IN THE PANHANDLE FRIDAY AFTERNOON WITH OVER A HALF INCH. IF THIS CONTINUES...WILL UNDOUBTEDLY HAVE TO RAISE POPS MORE THAN WHAT I HAVE IN THERE RIGHT NOW. SHORTWAVE CLEARS THE AREA TO THE EAST FRIDAY NIGHT...FORCING THE FRONTAL SYSTEM EAST AS WELL. BOTH THE GFS AND ECMWF DO HAVE SOME CONVECTION OVER NORTHERN WYOMING SATURDAY AFTERNOON THAT COULD SPILL INTO OUR NORTHERN ZONES...SO DO HAVE SOME SLIGHT CHANCE POPS GOING UP THAT WAY. DRY PATTERN FOR SUNDAY ON INTO THE REST OF THE EXTENDED AS SHORTWAVES TRACK ACROSS MONTANA. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 510 AM MDT TUE JUN 24 2014 OVERNIGHT CONVECTION CONTINUES UP NEAR KCDR AND KAIA THIS MORNING. EXPECT THIS TO WANE LATER THIS MORNING BEFORE PICKING UP AGAIN THIS AFTERNOON. && .FIRE WEATHER... ISSUED AT 224 AM MDT TUE JUN 24 2014 CONCERNS TO REMAIN LOW OVERALL THIS WEEK WITH MANY AREAS SEEING SOME RAIN AT ONE TIME OR ANOTHER. DRIEST AREAS WILL BE OVER FAR WESTERN DISTRICTS WITH MIN RHS LOWERING TO 10 TO 15 PERCENT. WINDS SHOULD NOT BE MUCH OF A FACTOR HOWEVER. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...JAMSKI SHORT TERM...RE LONG TERM...CLAYCOMB AVIATION...CLAYCOMB FIRE WEATHER...RE