Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/11/15


AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
641 AM CDT THU JUL 9 2015 .AVIATION... SCATTERED SHOWERS AND MAYBE A RUMBLE OF THUNDER WILL OCCUR OVER THE NORTH AS A FRONTAL SYSTEM MOVES AWAY. HIGH PRESSURE WILL BUILD IN FROM THE EAST ELSEWHERE. OCCASIONAL MVFR CONDITIONS WILL BE POSSIBLE OVER THE NORTH WITH VFR CONDITIONS ELSEWEHERE. WINDS WILL BE LIGHT AND SOUTHERLY. && .PREV DISCUSSION... /ISSUED 359 AM CDT THU JUL 9 2015/ SHORT TERM...TODAY THROUGH SUNDAY NIGHT A NEARLY STATIONARY FRONT REMAINS DRAPED ACROSS NORTHWEST ARKANSAS WITH SHOWERS AND THUNDERSTORMS CONTINUING TO DEVELOP ALONG THE FRONT. LATEST GUIDANCE SUGGESTS THAT THE FRONT MAY BE A BIT SLOWER TO PUSH TO THE NORTH THAN PREVIOUSLY ADVERTISED...AND THUS ADDED SLIGHT CHANCE POPS ACROSS NORTHERN ARKANSAS THROUGH 12Z FRIDAY. FORECAST PRECIPITABLE WATER VALUES WILL DECREASE BY CLOSE TO AN INCH ACROSS THE AREA ON THURSDAY...UNFORTUNATELY THIS STILL MEANS THAT 1.50" PLUS PRECIPITABLE WATER VALUES WILL STILL REMAIN ACROSS MUCH OF ARKANSAS. A SHORTWAVE WILL MOVE TO THE NORTH OF ARKANSAS THROUGH THE DAY TODAY FROM TEXAS. 6Z NAM AND 5Z HRRR ARE BY FAR THE MOST ENTHUSIASTIC WITH THIS FEATURE...EVEN BRINGING SOME HEAVY RAIN ACROSS NW AND NORTH CENTRAL ARKANSAS. MEANWHILE THE 00Z GFS/ECMWF/WRF ARE MUCH LESS ENTHUSIASTIC WITH THIS FEATURE. WITH FFG ACROSS NORTHERN ARKANSAS STILL WELL OVER 2" FOR 6HRS AND 1.5" FOR 2HRS...SIGNIFICANT UNCERTAINTY...AND THE 6Z HRRR COMING IN QUITE A BIT DRIER...THE PREVAILING THINKING IS THAT A FLASH FLOOD WATCH IS NOT WARRANTED ACROSS THE CWA AT THIS POINT. PRECIPITATION CHANCES DIMINISH ON FRIDAY AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION AND WILL BRING A RETURN OF HOT AND DRY WEATHER TO THE NATURAL STATE. HIGH TEMPERATURES THROUGH THE END OF THE SHORT TERM WILL WARM INTO THE LOWER TO MID 90S WITH HEAT INDEX VALUES FORECAST TO REACH TRIPLE DIGITS. LONG TERM...MONDAY THROUGH WEDNESDAY NO APPRECIABLE CHANGES WILL BE MADE TO THE EXTENDED FORECAST THIS MORNING AS ALL MEDIUM RANGE MODELS CONTINUE TO POINT TOWARDS KEEPING THE CENTER OF THE SUB-TROPICAL HIGH SITTING OVER THE SOUTHERN PLAINS. THIS WILL PLACE THE FORECAST AREA ON THE EASTERN PERIPHERY OF THE ANTI-CYCLONE WITH NORTHWEST FLOW ABOVE. SEVERAL RELATIVELY WEAK RIPPLES WILL MOVE THROUGH THE PREVAILING FLOW THROUGH THE PERIOD BUT POSITION OF THIS FEATURE WILL PRECLUDE PRECIPITATION CHANCES EXCEPT FOR THE EAST AND NORTHEAST PART OF THE FORECAST AREA. EVEN HERE...PRECIPITATION CHANCES WILL BE FAIRLY LOW BUT TEMPERATURES WILL REMAIN HOT WITH FORECASTED TEMPERATURES ACTUALLY AVERAGING A FEW DEGREES ABOVE NORMAL. && .PRELIMINARY POINT TEMPS/POPS... BATESVILLE AR 90 74 93 75 / 30 10 10 0 CAMDEN AR 95 74 95 74 / 10 10 10 0 HARRISON AR 83 69 90 71 / 50 20 0 0 HOT SPRINGS AR 92 72 93 73 / 10 10 10 0 LITTLE ROCK AR 93 74 94 74 / 10 10 10 0 MONTICELLO AR 94 76 94 76 / 10 0 10 0 MOUNT IDA AR 91 70 93 72 / 10 10 10 0 MOUNTAIN HOME AR 84 70 92 72 / 50 20 0 0 NEWPORT AR 91 75 93 76 / 20 10 10 0 PINE BLUFF AR 94 75 94 75 / 10 10 10 0 RUSSELLVILLE AR 89 70 93 72 / 20 10 10 0 SEARCY AR 91 74 93 75 / 10 10 10 0 STUTTGART AR 93 75 94 76 / 10 10 10 0 && .LZK WATCHES/WARNINGS/ADVISORIES...NONE. && $$ AVIATION...56
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
359 AM CDT THU JUL 9 2015 .SHORT TERM...TODAY THROUGH SUNDAY NIGHT A NEARLY STATIONARY FRONT REMAINS DRAPED ACROSS NORTHWEST ARKANSAS WITH SHOWERS AND THUNDERSTORMS CONTINUING TO DEVELOP ALONG THE FRONT. LATEST GUIDANCE SUGGESTS THAT THE FRONT MAY BE A BIT SLOWER TO PUSH TO THE NORTH THAN PREVIOUSLY ADVERTISED...AND THUS ADDED SLIGHT CHANCE POPS ACROSS NORTHERN ARKANSAS THROUGH 12Z FRIDAY. FORECAST PRECIPITABLE WATER VALUES WILL DECREASE BY CLOSE TO AN INCH ACROSS THE AREA ON THURSDAY...UNFORTUNATELY THIS STILL MEANS THAT 1.50" PLUS PRECIPITABLE WATER VALUES WILL STILL REMAIN ACROSS MUCH OF ARKANSAS. A SHORTWAVE WILL MOVE TO THE NORTH OF ARKANSAS THROUGH THE DAY TODAY FROM TEXAS. 6Z NAM AND 5Z HRRR ARE BY FAR THE MOST ENTHUSIASTIC WITH THIS FEATURE...EVEN BRINGING SOME HEAVY RAIN ACROSS NW AND NORTH CENTRAL ARKANSAS. MEANWHILE THE 00Z GFS/ECMWF/WRF ARE MUCH LESS ENTHUSIASTIC WITH THIS FEATURE. WITH FFG ACROSS NORTHERN ARKANSAS STILL WELL OVER 2" FOR 6HRS AND 1.5" FOR 2HRS...SIGNIFICANT UNCERTAINTY...AND THE 6Z HRRR COMING IN QUITE A BIT DRIER...THE PREVAILING THINKING IS THAT A FLASH FLOOD WATCH IS NOT WARRANTED ACROSS THE CWA AT THIS POINT. PRECIPITATION CHANCES DIMINISH ON FRIDAY AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION AND WILL BRING A RETURN OF HOT AND DRY WEATHER TO THE NATURAL STATE. HIGH TEMPERATURES THROUGH THE END OF THE SHORT TERM WILL WARM INTO THE LOWER TO MID 90S WITH HEAT INDEX VALUES FORECAST TO REACH TRIPLE DIGITS. && .LONG TERM...MONDAY THROUGH WEDNESDAY NO APPRECIABLE CHANGES WILL BE MADE TO THE EXTENDED FORECAST THIS MORNING AS ALL MEDIUM RANGE MODELS CONTINUE TO POINT TOWARDS KEEPING THE CENTER OF THE SUB-TROPICAL HIGH SITTING OVER THE SOUTHERN PLAINS. THIS WILL PLACE THE FORECAST AREA ON THE EASTERN PERIPHERY OF THE ANTI-CYCLONE WITH NORTHWEST FLOW ABOVE. SEVERAL RELATIVELY WEAK RIPPLES WILL MOVE THROUGH THE PREVAILING FLOW THROUGH THE PERIOD BUT POSITION OF THIS FEATURE WILL PRECLUDE PRECIPITATION CHANCES EXCEPT FOR THE EAST AND NORTHEAST PART OF THE FORECAST AREA. EVEN HERE...PRECIPITATION CHANCES WILL BE FAIRLY LOW BUT TEMPERATURES WILL REMAIN HOT WITH FORECASTED TEMPERATURES ACTUALLY AVERAGING A FEW DEGREES ABOVE NORMAL. && .PRELIMINARY POINT TEMPS/POPS... BATESVILLE AR 90 74 93 75 / 30 10 10 0 CAMDEN AR 95 74 95 74 / 10 10 10 0 HARRISON AR 83 69 90 71 / 50 20 0 0 HOT SPRINGS AR 92 72 93 73 / 10 10 10 0 LITTLE ROCK AR 93 74 94 74 / 10 10 10 0 MONTICELLO AR 94 76 94 76 / 10 0 10 0 MOUNT IDA AR 91 70 93 72 / 10 10 10 0 MOUNTAIN HOME AR 84 70 92 72 / 50 20 0 0 NEWPORT AR 91 75 93 76 / 20 10 10 0 PINE BLUFF AR 94 75 94 75 / 10 10 10 0 RUSSELLVILLE AR 89 70 93 72 / 20 10 10 0 SEARCY AR 91 74 93 75 / 10 10 10 0 STUTTGART AR 93 75 94 76 / 10 10 10 0 && .LZK WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...65 / LONG TERM...56
AREA FORECAST DISCUSSION
NWS TUCSON AZ
855 AM MST FRI JUL 10 2015 .SYNOPSIS...ISOLATED TO SCATTERED THUNDERSTORMS MAY DEVELOP FARTHER WEST FRIDAY NIGHT WITH SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS PREVAILING THIS WEEKEND INTO EARLY NEXT WEEK. A GRADUAL WARMING TREND WILL OCCUR DURING THE NEXT SEVERAL DAYS...WITH ABOVE NORMAL HIGH TEMPERATURES RETURNING BY THE MIDDLE OF NEXT WEEK. && .DISCUSSION...THUNDERSTORMS HAVE PERSISTED IN PORTIONS OF GRAHAM...GREENLEE AND NRN COCHISE COUNTY THIS EVENING. SATELLITE SHOWS JET SEGMENTS LINED UP TO TRAVERSE THE REGION OVERNIGHT. MODELS SHOWING SLIGHT BACKING OF MID LEVEL WINDS TO A MORE DUE SOUTH TO NORTH DIRECTION. THIS IS ALSO EVIDENT ON SATELLITE IN SLIGHT NORTHWARD PUSH OF CLOUD MASS OVER BAJA/NW SONORA. 315K ISENTROPIC SURFACE SHOWS ADEQUATE LIFT AND LOW CONDENSATION PRESSURE DEFICITS IN AN UNSTABLE AIR MASS FROM TUCSON EASTWARD 06-12Z TONIGHT. THIS POINTS TO POSSIBLE ELEVATED CONVECTION DEVELOPING DURING THE OVERNIGHT HOURS. THUS WILL MOVE BACK EDGE OF SLIGHT CHANCE THUNDERSTORM CATEGORY AS FAR WEST AS TUCSON DURING THE OVERNIGHT HOURS. HRRR AND NAM AND TO A LESSER EXTENT THE GFS QPF FIELDS ALL POINTING TO THE POSSIBILITY OF OVERNIGHT TSTORMS. && .AVIATION...VALID THRU 12/06Z. ISOLATED TO SCATTERED SHRA/TSRA NORTH AND EAST OF KTUS-KFHU LINE POSSIBLE OVERNIGHT WITH DEVELOPMENT AGAIN SATURDAY AFTERNOON. TSRA COULD GUST TO 35 KTS. OTHERWISE SFC WINDS LESS THAN 10 KTS EXCEPT S TO SW WINDS 10-15 KTS G 20KTS AFT 11/18Z. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...ISOLATED TO SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS WILL THEN OCCUR THIS WEEKEND INTO EARLY NEXT WEEK. SW WINDS 10-20 MPH SATURDAY AFTERNOON OTHERWISE EXPECT GENERALLY LIGHT TERRAIN DRIVEN WINDS OUTSIDE OF THUNDERSTORMS SUNDAY AND DURING MUCH OF THE UPCOMING WEEK. && .PREV DISCUSSION...THE UPPER WEATHER PATTERN IS DEFINED BY A TROUGH OF LOW PRESSURE ACROSS CALIFORNIA/NEVADA AND A BROAD RIDGE OF HIGH PRESSURE NEAR LOUISIANA/MISSISSIPPI. THE LATEST WATER VAPOR IMAGERY DEPICTED MAINLY DRY AIR ALOFT ACROSS THE MAJORITY OF THE FORECAST AREA...WITH THE EXCEPTION IN FAR SE AZ IN WHICH A MOIST PLUME CAN BE SEEN EXTENDING AROUND THE BASE OF THE TROUGH INTO EAST CENTRAL NEW MEXICO. DISTURBANCES IN THE FLOW ALONG THIS MOISTURE BOUNDARY HAVE RESULTED IN STRONG TO SEVERE STORMS TODAY...ESPECIALLY AS STORMS MOVED CLOSER TO THE NEW MEXICO BORDER WHERE A MORE FAVORABLE SHEAR ENVIRONMENT EXISTS. THE UPPER HIGH CENTER BEGINS TO SHIFT WEST THIS WEEKEND...WHICH WILL RESULT IN A SOUTHERLY FLOW FOR OUR NECK OF THE WOODS. THIS SHOULD ALLOW STORMS TO INCREASE IN COVERAGE ACROSS SOUTHEAST ARIZONA INTO EARLY NEXT WEEK. THE UPPER HIGH CENTER THEN BEGINS TO NUDGE JUST SOUTH COCHISE COUNTY BY THE MIDDLE OF NEXT WEEK. THIS PATTERN TYPICALLY SHUTS STORMS DOWN BY ELIMINATING THE SUBTLE UPPER FEATURES THAT HELP ENHANCE THUNDERSTORM ACTIVITY. HOWEVER...ENOUGH MOISTURE WILL BE PRESENT FOR ISOLATED STORMS TO DEVELOP VIA SOLAR HEATING. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DROZD VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
935 PM MST WED JUL 8 2015 .SYNOPSIS... THUNDERSTORM CHANCES WILL BE SIGNIFICANTLY LOWER THAN USUAL FOR THE MIDDLE OF THE MONSOON SEASON...AND PRIMARILY RELEGATED TO THE MOUNTAINS OF NORTHERN AND EASTERN ARIZONA THE NEXT SEVERAL DAYS. DESPITE THE LACK OF STORM ACTIVITY...TEMPERATURES WILL REMAIN NEAR TO SLIGHTLY BELOW NORMAL. THIS WEEKEND AND EARLY NEXT WEEK...HIGH PRESSURE WILL STRENGTHEN AGAIN LEADING TO WARMER TEMPERATURES. THERE MAY ALSO BE AN INCREASE IN STORM ACTIVITY...MAINLY OVER EASTERN ARIZONA. && .DISCUSSION... MINIMAL RADAR ACTIVITY OCCURRED ACROSS OUR FORECAST AREA THIS EVENING...WITH ONLY A FEW SHORT-LIVED THUNDERSHOWERS THAT SKIRTED THE SOUTHERN GILA COUNTY HIGHER TERRAIN A FEW HOURS AGO. 00Z/03Z PSR BALLOONS INDICATED THE DEEP MIXING PROFILE TODAY AND A THINNING PWAT SFC DOWN AROUND THE 1 INCH MARK...ALONG WITH DOMINANT WEST TO SOUTHWEST WINDS THROUGH THE MAJORITY OF THE PROFILE. THE UNSEASONABLY STRONG WESTERLY WINDS ALSO SHUNTED THE STORM ACTIVITY OFF WELL TO OUR EAST AND NORTH...KEEPING AREAS OF NM...UT...AND CO BUSY WITH STORMS THIS EVENING. WHILE THE RADAR SCOPES WERE GENERALLY QUIET TONIGHT...STRONG WESTERLY GAP/SUNDOWNER WINDS CONTINUE ALONG THE PENINSULAR RANGES BETWEEN SAN DIEGO AND IMPERIAL COUNTIES. LATEST OBS OUT OF EL CENTRO NAS HAVE WIND GUSTS IN THE 30S WITH SOME VISIBILITY REDUCTION IN BLOWING DUST. EVENING CROSS SECTION MODEL FCSTS INDICATE THE STABLE LAYER DEFLECTION AND RESULTING GUSTY SFC WINDS INTO THE IMPERIAL VALLEY...AND EVEN A BIT FURTHER INTO THE FAR EASTERN REACHES OF IMPERIAL COUNTY...WILL CONTINUE FOR THE NEXT SEVERAL HOURS. WIND ADVISORY CONTINUES FOR THE I8 GRADE INTO IN-KO-PAH THROUGH THURSDAY AM. GRID UPDATES TONIGHT INCLUDED EXPANDING THE COVERAGE OF PATCHY BLOWING DUST/SAND WORDING THROUGH EL CENTRO/IMPERIAL OVERNIGHT. THE GFS-GEM-NAM 00Z RUNS INDICATE SOME POTENTIAL PRECIP ACTIVITY BUBBLING UP OVER GILA AND FAR EASTERN PINAL COUNTIES TOWARDS SUNRISE THURSDAY...POSSIBLY SIMILAR TO THE THIN BAND OF ACTIVITY OBSERVED ACROSS THE AREA THIS MORNING. EVENING HI-RES FCSTS ARE NOT AS ENTHUSED...BUT THE HRRR SAT FCST PRODUCT DOES INDICATE SOME COOLER CLOUD TOPS AND MAYBE A SHOWER OR TWO ALONG THE RIM AND EASTERN AZ HIGHER TERRAIN TOWARDS THURSDAY MORNING. KEPT SLIGHT CHANCES FOR THUNDER OVERNIGHT FOR THOSE AREAS WHILE MOSTLY ZEROING OUT POPS FOR THE LOWER DESERT ELEVATIONS. && .PREVIOUS DISCUSSION... A SUBTLE SHORTWAVE WITHIN THE STRONG SOUTHWEST FLOW ALOFT AND ASSOCIATED MOISTURE AXIS HAS LIFTED NORTHEAST WITH LARGER SCALE SUBSIDENCE AND ADDITIONAL DRYING WORKING INTO THE MAJORITY OF THE FORECAST AREA THIS AFTERNOON. OBJECTIVE ANALYSIS INDICATES INSTABILITY SOLELY RELEGATED TO THE NORTHERN AND EASTERN PORTIONS OF THE STATE...WITH LITTLE TO NO OPPORTUNITY FOR ADDITIONAL AFTERNOON CONVECTION (SANS SRN GILA COUNTY). THEREFORE...ATTENTION TURNS TO IMPACTS FROM GUSTY WINDS INCLUDING THE STRONG LIKELIHOOD FOR AN IMPRESSIVE AND UNSEASONABLE SUNDOWNER EVENT THROUGH SWRN IMPERIAL COUNTY. THE AREA WEST OF EL CENTRO THROUGH THE IN-KO-PAH GORGE ALONG I-8 WILL LIKELY EXPERIENCE PERIODIC GUSTS AROUND 45 MPH CREATING HAZARDOUS DRIVING CONDITIONS FOR HIGH PROFILE VEHICLES...JUSTIFYING A WIND ADVISORY FOR JUST THE SMALL SOUTHWEST SEGMENT OF IMPERIAL COUNTY. WHILE STRONGER WINDS MAY BEGIN AS EARLY AS LATE THIS AFTERNOON...TRADITIONALLY THE TIMING OF STRONGEST WINDS SUGGESTS AROUND AND THE FEW HOURS AFTER SUNSET WILL EXPERIENCE THE STRONGEST GUSTS AND LARGEST IMPACTS. THURSDAY AND FRIDAY... THE UPPER LOW BECOMES CENTERED OVER CALIFORNIA THURSDAY WITH AN ANOMALOUS JET STREAK AND VORT MAX RAPIDLY SWINGING THROUGH THE MOHAVE DESERT REGION DURING THE AFTERNOON AND EVENING. IN FACT...12Z KTWC AND KNKX SOUNDINGS SAMPLED H2 WESTERLY WINDS NEAR 100KT...CORRESPONDING TO A U-WIND COMPONENT ANOMALY OF AN IMPRESSIVE 4-5 NORMALIZED STANDARD DEVIATIONS ABOVE AVERAGE (VERY UN-MONSOON SEASON LIKE). GIVEN THE UNUSUAL JET STRENGTH...A NICE BULLSEYE OF Q FORCING ASSOCIATED WITH THE VORTICITY CENTER LIFTS INTO NWRN ARIZONA...HOWEVER ONLY BRUSHES EASTERN ARIZONA WHERE THE BETTER MOISTURE RESIDES. TO VARYING DEGREES...MODELS DO INDICATE MOISTURE INCREASING WITH BACKED MIDLEVEL WINDS OVER SOUTHEAST ARIZONA THURSDAY IN RESPONSE TO THE APPROACHING LOW. THUS...SOMEWHAT HIGHER POPS OVER THE EASTERN CWA WERE RETAINED. THIS LOW ALSO WILL PROVIDE COOLER TEMPERATURES THURSDAY...ESPECIALLY IN WESTERN PORTIONS OF THE FORECAST AREA. IN FACT...A NUMBER OF LOCATIONS OVER SOUTHEAST CALIFORNIA AND FAR SOUTHWEST ARIZONA ARE ANTICIPATED TO REMAIN JUST BELOW 100 DEGREES. HIGH TEMPS OVER SOUTH-CENTRAL ARIZONA INCLUDING THE PHOENIX AREA WILL BE SLIGHTLY WARMER BUT STILL BELOW NORMAL. AS THE FIRST LOW PRESSURE SYSTEM QUICKLY MOVES NORTHEASTWARD AND WEAKENS...TROUGHING NEAR THE CALIFORNIA COAST REDEVELOPS FRIDAY. THUS ANTICIPATE LITTLE CHANGE IN TEMPERATURES...AND EVEN LESS STORM ACTIVITY WITH RENEWED STRONG SWLY FLOW ALOFT. SATURDAY AND SUNDAY... HIGH PRESSURE OVER NORTHERN MEXICO AS WELL AS THE SOUTHEAST STATES IS PROGGED TO CONSOLIDATE AND BECOME CENTERED OVER WEST TEXAS THIS WEEKEND. THERE CONTINUES TO BE DIFFERENCES IN THE DETAILS BETWEEN THE GFS AND ECMWF....WITH THE GFS DEVELOPING DEEPER SOUTHERLY FLOW AND ADVECTING MORE MOISTURE INTO THE REGION VERSUS THE ECMWF. EVEN TAKING THE GFS AT FACE VALUE...1000-700MB MEAN MIXING RATIOS LOOK BORDERLINE FOR ORGANIZED CONVECTION AND THIS IS REFLECTED IN MODEST FORECAST CAPE. WOULD ANTICIPATE THAT STORM ACTIVITY OVER SOUTHEAST ARIZONA WILL IMPINGE UPON SOUTH-CENTRAL ARIZONA THIS WEEKEND...HOWEVER IT LOOKS LIKE A SITUATION WHERE STORMS WILL STRUGGLE TO SURVIVE OVER THE LOWER DESERTS AND BLOWING DUST WOULD BE THE MOST LIKELY IMPACT. OF NOTE...THE GFS BRINGS A PERTURBATION/VORT MAX THROUGH THE AREA ON SUNDAY WHICH WOULD SUGGEST A BETTER CHANCE OF STORMS SUNDAY VERSUS SATURDAY BUT CANNOT PUT A LOT OF STOCK IN THAT SCENARIO THIS FAR OUT. WITH THE RIDGE STRENGTHENING...TEMPS BEGIN A WARMING TREND TO NEAR NORMAL. MONDAY AND TUESDAY... THE GFS CONTINUES TO DEPICT MORE OF A SOUTHERLY COMPONENT TO THE FLOW FOR MONDAY THAN THE ECMWF RESULTING IN MORE MOISTURE...BUT IT STILL LOOKS BORDERLINE. THE GFS THEN SHOWS SOME DECLINE IN MOISTURE TUESDAY AS THE COASTAL TROUGHING MOVES ASHORE AND THE RIDGE SAGS SOUTHWARD A BIT. STILL NOT AS DRY AS ECMWF BUT ENOUGH SUCH THAT STORM ACTIVITY WOULD BE MEAGER. FURTHER WARMING IS EXPECTED EARLY NEXT WEEK WITH HIGHS AT MANY OF THE LOW DESERT LOCATIONS REACHING THE 110 DEGREE MARK. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... ELEVATED WEST SFC WINDS TO PERSIST LATE INTO THIS EVENING...POSSIBLY LASTING THROUGH THE 09/10-11Z AM HOURS. CONFIDENCE IS LOW IN TIMING THE SHIFT FOR KPHX...BUT BETTER FOR THE SATELLITE AIRFIELDS OF KSDL AND KIWA. EARLY EVENING SKIES MOSTLY CLEAR WITH HIGH LEVEL CLOUDS GNLY AOA 25KFT MOVING FROM THE WEST TOWARDS EARLY THURSDAY AM. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... GUSTY SOUTHWEST WINDS WILL BE COMMON THROUGH THE EVENING HOURS. FAVORED DOWNSLOPE AREAS WILL SEE THE STRONGEST GUSTS...IN EXCESS OF 35KT...WHICH WILL LAST WELL INTO THE OVERNIGHT HOURS. AFTER SUNRISE/13Z WINDS WILL TEMPORARILY WEAKEN THEN PICK BACK UP NEAR 18Z ALBEIT WEAKER. EARLY EVENING SKIES TO REMAIN MOSTLY CLEAR BEFORE HIGH LEVEL CLOUDS MOVE IN FROM THE WEST...GNLY AOA 20-25KFT. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... FRIDAY THROUGH TUESDAY... THE FLOW PATTERN WILL TRANSITION FROM SOUTHWESTERLY AND UNFAVORABLE FOR EXTENSIVE MOISTURE AND STORMS DURING THE FIRST PART OF THE WEEKEND...TO MORE TRADITIONAL MONSOON SEASON SOUTHERLY EARLY NEXT WEEK. THUNDERSTORM CHANCES WILL MOSTLY BE LIMITED TO HIGHER TERRAIN LOCATIONS NORTH AND EAST OF PHOENIX...THOUGH COULD BEGIN MOVING WESTWARD NEXT WEEK. AFTERNOON HUMIDITY LEVELS IN A 10-20 PERCENT RANGE DURING THE WEEKEND WILL INCREASE TO A 15-25 PERCENT RANGE NEXT WEEK. OVERNIGHT RECOVERY WILL BE GOOD. DIURNALLY DRIVEN WINDS SPEEDS AND DIRECTIONS WILL PREDOMINATE MUCH OF THIS TIME...THOUGH STRONGER THAN USUAL AFTERNOON UPSLOPE GUSTINESS WILL STILL BE EVIDENT ACROSS MUCH OF THE DISTRICT. && .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...WIND ADVISORY FROM 3 PM THIS AFTERNOON TO 7 AM PDT THURSDAY FOR CAZ033. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...NOLTE PREVIOUS DISCUSSION...MO/AJ AVIATION...NOLTE/INIGUEZ FIRE WEATHER...18
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
844 AM PDT THU JUL 9 2015 .SYNOPSIS... A LOW PRESSURE SYSTEM WILL MOVE ACROSS THE AREA TODAY AND BRING BELOW AVERAGE TEMPERATURES AND SHOWERS AND THUNDERSTORMS TO THE CENTRAL CALIFORNIA INTERIOR. THE LOW WILL MOVE EAST OF THE REGION ON FRIDAY AND A DRY SOUTHWEST FLOW WILL THEN PREVAIL OVER THE WEEKEND AND INTO THE EARLY PART OF NEXT WEEK. TEMPERATURES WILL WARM FRIDAY THROUGH THE WEEKEND...AND DRY CONDITIONS WILL PREVAIL THROUGHOUT THE AREA BY SATURDAY. && .DISCUSSION... DYNAMICS WITH AN UPPER LOW MOVING INLAND HAS RESULTED IN SCATTERED THUNDERSTORMS IN PARTS OF THE SAN JOAQUIN VALLEY EARLY THIS MORNING. THE STORMS HAVE PROVIDE LOCALLY HEAVY RAIN DUE TO A SLOW STORM MOVEMENT. 12Z OAK SOUNDING SHOWS HIGH PRECIPITABLE WATER VALUES 1.09 INCH. THUS MAIN THREAT WITH THESE STORMS WILL BE LOCALLY HEAVY RAIN CAUSING FLASH FLOODING IN LOW LYING AREAS OF THE SJV. HAVE UPDATED FORECAST RAIN AMOUNTS AS WELL INCREASED PROBABILITY OF PRECIPITATION ACROSS THE CENTRAL VALLEY. && .PREV DISCUSSION... /ISSUED 325 AM PDT THU JUL 9 2015/ DISCUSSION...IR/WV IMAGERY INDICATING THE UPPER LOW WHICH HAS BEEN SLOWLY MOVING EAST OFF THE CENTRAL CA COAST OVER THE PAST FEW DAYS...IS FINALLY PUSHING INLAND THIS MORNING. THIS HAS BROUGHT ENOUGH INSTABILITY TO PROVIDE FOR A FEW SHOWERS AND ISOLATED THUNDERSTORMS OVER THE SOUTHWESTERN SAN JOAQUIN VALLEY AS WELL AS OVER THE SOUTHERN SIERRA NEVADA. RECENT RUNS OF THE HRRR HAS INDICATED SOME POTENTIAL FOR CONVECTION THIS MORNING...WITH THE SOUTHERN SIERRA NEVADA BEING THE MOST FAVORED AREA. A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS CONTINUES OVERNIGHT FOR THE HIGHER ELEVATIONS OF THE SOUTHERN SIERRA NEVADA AS WELL AS FOR THE PORTIONS OF THE WEST SIDE OF THE SAN JOAQUIN VALLEY. THE LOW HAS ALSO BROUGHT INCREASED ONSHORE FLOW OVER CENTRAL CA RESULTING IN GUSTY WINDS THROUGH THE PASSES OF THE COASTAL RANGE. A WIND ADVISORY REMAINS IN EFFECT FOR THE WEST SIDE OF THE SAN JOAQUIN VALLEY WEST OF THE INTERSTATE 5 CORRIDOR THROUGH 500 AM PDT THIS MORNING WHERE FREQUENT GUSTS ABOVE 35 MPH HAVE BEEN OBSERVED OVERNIGHT. THE HRRR IS INDICATING THE LOW MOVING EAST ACROSS OUR CWFA TODAY AND PROVIDING OUR AREA WITH INCREASED CLOUDS...MOUNTAIN CONVECTION AND COOLER TEMPERATURES AS FORECASTED HIGHS ARE EXPECTED TO BE 7-10 DEGREES BELOW SEASONAL NORMALS IN THE SAN JOAQUIN VALLEY TODAY. THE 06Z WRF IS INDICATING THE LOW WILL OPEN UP AND MOVE EAST OF OUR AREA TONIGHT AND INTO THE GREAT BASIN ON FRIDAY. A WARMING AND DRYING TREND IS EXPECTED TO COMMENCE ON FRIDAY WITH TEMPERATURES TRENDING UPWARD...BUT STILL BELOW SEASONAL NORMALS. SHOWERS AND THUNDERSTORMS WILL BE CONFINED TO THE HIGHER ELEVATIONS OF THE SOUTHERN SIERRA NEVADA ON FRIDAY AS THE PREVAILING AIRMASS BECOMES MORE STABLE. A DRY SOUTHWEST FLOW IS EXPECTED TO PREVAIL ACROSS CENTRAL CA THIS WEEKEND. RISES IN HEIGHTS AND DIURNAL THICKNESSES ACROSS OUR AREA WILL TEMPERATURES TRENDING UPWARD AND RETURNING TO SEASONAL NORMALS BY EARLY NEXT WEEK. RH PROGS ARE INDICATING DRIER AIR AT THE MID/UPPER LAYERS SO OUR AREA SO EXPECT OUR AREA TO BE MOSTLY CLEAR AND FREE OF PRECIPITATION THIS WEEKEND ALTHOUGH A FEW CUMULUS BUILDUPS WILL BE POSSIBLE NEAR THE SIERRA CREST ON SATURDAY AS A RESULT OF SOME LINGERING INSTABILITY. THE MEDIUM RANGE MODELS ARE IN FAIRLY GOOD AGREEMENT THIS MORNING INDICATING CENTRAL CA WILL REMAIN UNDER A DRY SOUTHWEST FLOW FOR MUCH OF NEXT WEEK AS A RESULT OF INTERACTION BETWEEN AN UPPER RIDGE OVER THE SOUTH CENTRAL CONUS AND A BAGGY UPPER TROUGH OFF THE WESTERN CONUS COAST. THIS WILL RESULT IN DRY CONDITIONS AND NEAR SEASONAL TEMPERATURES FOR MONDAY THROUGH THE MIDDLE OF NEXT WEEK. && .AVIATION... LOCAL IFR CONDITIONS IN ISOLATED THUNDERSTORMS IN THE SAN JOAQUIN VALLEY UNTIL 03Z. AREAS OF MVFR WITH LOCAL IFR AND TERRAIN OBSCURATIONS IN SHOWERS AND THUNDERSTORMS OVER THE SOUTHERN SIERRA NEVADA THROUGH 06Z FRIDAY. OTHERWISE...VFR CONDITIONS WILL PREVAIL THROUGHOUT THE CENTRAL CA INTERIOR DURING THE NEXT 24 HOURS. && .AIR QUALITY ISSUES... NONE. && .CERTAINTY... THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS MEDIUM. THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM. THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD. CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL INFORMATION AND/OR TO PROVIDE FEEDBACK. && .CLIMATE... RECORDS SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR KFAT 07-09 113:1905 78:1936 81:2008 55:1983 KFAT 07-10 112:2008 81:1974 82:2008 54:1904 KFAT 07-11 110:1961 82:1888 78:2002 52:1974 KBFL 07-09 113:1905 83:1980 84:2008 52:1923 KBFL 07-10 113:1905 82:1936 85:2008 51:1914 KBFL 07-11 110:1961 83:1936 79:2002 51:1906 && .HNX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ PUBLIC...MV AVN/FW...BEAN PREV DISCUSSION...DS SYNOPSIS...BSO WEATHER.GOV/HANFORD
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NWS LOS ANGELES/OXNARD CA
750 AM PDT THU JUL 9 2015 .SYNOPSIS... LOW PRESSURE OVERHEAD TODAY WILL BRING THE SLIGHT CHANCE OF THUNDERSTORMS TO SOME MOUNTAIN AREAS. LOW PRESSURE EXITS THE REGION TOMORROW WHICH WILL LEAD TO A GRADUAL WARMING TREND INTO NEXT WEEK...WITH TEMPERATURES TRENDING TOWARDS SEASONAL VALUES AND LOW CLOUDS AND PATCHY FOG RESTRICTED TO TYPICAL AREAS WEST OF THE MOUNTAINS. && .SHORT TERM (TODAY-SAT)...AN INTERESTING WEATHER PATTERN IS SETTING UP THIS MORNING. A UNSEASONABLE UPPER LEVEL CUTOFF LOW WAS JUST SOUTH OF MONTEREY CALIFORNIA THIS MORNING. THIS UPPER LOW WILL ONLY DROP SOUTH TO SAN LUIS OBISPO COUNTY THIS MORNING BEFORE PUSHING EAST AND FILLING IN BY THIS EVENING. A FEW THUNDERSTORMS WERE ALREADY STARTING TO KICK UP OVER NW KERN COUNTY NEAR THE CORE OF THE UPPER LOW BETWEEN LOST HILLS AND BUTTONWILLOW. THE HRRR MODEL INITIATED WELL AND SHOWED THESE SHOWERS BEING SHORT LIVED AS THEY MOVE TO THE NE. NOT MUCH CONVECTION EXPECTED WITH THE UPPER LOW ITSELF TODAY. HOWEVER BY THIS AFTERNOON...MODELS ARE SUGGESTING SOME INSTABILITY OVER THE MOUNTAINS...WITH THE BEST CHANCE OF THUNDERSTORM POTENTIAL OVER THE VENTURA COUNTY MTNS AND THE ADJACENT EASTERN PORTION OF THE SANTA BARBARA COUNTY MTNS. LATEST MODEL SOUNDINGS AROUND MT BALDY IN L.A. COUNTY WAS INDICATING A FAIRLY STRONG CAP TO INHIBIT THUNDERSTORM DEVELOPMENT. HOWEVER FURTHER WEST THERE WAS ENOUGH COOLING ALOFT ASSOCIATED WITH THE UPPER LOW TO TRIGGER A FEW THUNDERSTORMS. BEST MOISTURE POOL WAS AROUND 700 MB OVER THE VENTURA COUNTY MTNS WHERE WE ARE EXPECTING THE BEST CHANCE FOR ISOLATED THUNDERSTORMS TO DEVELOP THIS AFTERNOON. THE PRECIPITABLE WATERS WILL BE LESS THAN AN INCH. THE COMBINATION OF MODEST PW...AND WESTERLY STEERING WINDS 15 TO 20 MPH WILL HELP STORMS MOVE ALONG MAKING IT DIFFICULT FOR ANY FLASH FLOODING TO OCCUR. THERE COULD BE BRIEF PERIODS OF LOCALLY HEAVY RAIN AT TIMES AROUND THE LOCKWOOD VALLEY AREA WHICH COULD CAUSE SOME LOCALLY FLOODED ROADS. FOR MOST OF THE FORECAST AREA...THE MAIN STORY WILL BE THE VERY DEEP MARINE LAYER OR DEEP (STABLE)MOIST LAYER AS HIGH AS 5000 FT DEEP THIS MORNING. THERE WILL BE ENOUGH LIFT IN THE ATMOSPHERE TO HELP SQUEEZE OUT SOME DRIZZLE JUST ABOUT ANYWHERE WEST OF THE MOUNTAINS THIS MORNING...OR EVEN SOME LIGHT STRATIFORM LIGHT RAIN ACROSS THE ELEVATED VALLEYS AND FOOTHILLS OF LA/VTU COUNTIES WITH LESS THAN A TENTH OF AN INCH OF RAIN POSSIBLE...MAINLY AROUND LA CANADA AND LA CRESCENTA FOOTHILLS. CLOUDS WILL LIKELY LINGER ALL DAY ALONG THE COAST AND REMAIN MOSTLY CLOUDY FOR VALLEYS IN THE MORNING WITH ONLY PARTIAL CLEARING IN THE AFTERNOON. OR...THERE COULD BE A REVERSE CLEARING SITUATION WHERE THE BEACHES CLEAR BY THE EARLY AFTERNOON AND SKIES REMAIN MOSTLY CLOUDY ACROSS VALLEYS AND FOOTHILLS. TODAY WILL BE THE COOLEST DAY OF THE WEEK...WHICH HAS ALREADY BEEN WELL BELOW AVERAGE FOR THIS TIME OF YEAR FROM YESTERDAY`S HIGHS. HIGH TEMPS ACROSS MOST VALLEYS WILL REMAIN IN THE 70S TO AROUND 80 IN THE WARMEST SPOTS. THE ANTELOPE VALLEY WILL ONLY REACH THE LOWER 80S AS WELL. THE NORMAL HIGH FOR LANCASTER THIS TIME OF YEAR IS AROUND 97 DEGREES. BY FRIDAY...IN THE WAKE OF THE UPPER TROUGH MOVING NE...ANOTHER DEEPER BROAD UPPER TROUGH WILL LINGER ACROSS CALIFORNIA THROUGH AT LEAST SATURDAY...WHILE HIGH PRESSURE ALOFT OVER TEXAS WILL BECOME ELONGATED AND NUDGE INTO THE MOST SOUTHERN PORTION OF EASTERN CALIFORNIA. HIGH TEMPS WILL BEGIN TO REBOUND BOTH FRI AND SAT A FEW DEGREES EACH DAY WITH NIGHT THROUGH MORNING LOW CLOUDS CONTINUING ACROSS COAST AND COASTAL VALLEYS. .LONG TERM (SUN-WED)... BOTH THE GFS AND ECMWF ARE IN FAIRLY GOOD AGREEMENT KEEPING A RELATIVELY WEAK UPPER TROUGH OVER MUCH OF CALIFORNIA WHILE THE UPPER LVL RIDGE OVER AZ/EASTERN SOUTHERN CALIFORNIA TRIES TO NUDGE IN UNDER THE TROUGH. BY WEDNESDAY HIGH PRESSURE STARTS TO GET MORE CONTROL OF SOUTHERN CALIFORNIA WHILE THE UPPER TROUGH RETREATS A BIT TO THE NORTH. EXPECT TEMPS TO CLIMB TUE/WED WITH HIGHS LIKELY REACHING THE LOWER TO MID 90S ACROSS INLAND VALLEYS...LOWER MOUNTAIN ELEVATIONS AND THE ANTELOPE VALLEY. THERE WILL CONTINUE TO BE GUSTY SW WINDS ACROSS PORTIONS OF THE ANTELOPE VALLEY...WHILE COAST AND SOME COASTAL VALLEYS WILL CONTINUE WITH NIGHT THROUGH MORNING LOW CLOUDS. THE INVERSION WILL BE SHALLOWER SO VALLEYS SHOULD CLEAR QUICKER WHILE A FEW BEACH CITIES MIGHT FIND IT TOUGH TO CLEAR IN THE AFTERNOON. && .AVIATION...09/0703Z. AT 06Z...THE MARINE LAYER DEPTH AT KLAX WAS BASED AROUND 4300 FEET. THE TOP OF THE INVERSION WAS AROUND 5400 FEET WITH A TEMPERATURE OF 14 DEGREES CELSIUS. MVFR CONDITIONS WILL LIKELY SPREAD INTO MOST COASTAL AND VALLEY TERMINALS THROUGH 08Z. THERE IS A SLIGHT CHANCE OF IFR CONDITIONS IN DRIZZLE BETWEEN 10Z AND 16Z. THERE IS A CHANCE OF MVFR CONDITIONS OR CEILINGS AT OR BELOW 5000 FEET LINGERING THROUGHOUT THURSDAY AFTERNOON. KLAX AND KBUR...MVFR CONDITIONS WILL LIKELY PERSIST THROUGH AT LEAST 21Z. THERE IS A 20 PERCENT CHANCE OF IFR CONDITIONS IN DRIZZLE BETWEEN 10Z AND 16Z. THERE IS A 40 PERCENT CHANCE OF MVFR CONDITIONS OR CEILINGS AT OR BELOW 5000 FEET LINGERING THROUGHOUT THURSDAY AFTERNOON. && .MARINE...09/300 AM. NO SIGNIFICANT WEATHER IS EXPECTED ACROSS THE COASTAL WATERS THROUGH THROUGH FRIDAY NIGHT. THERE IS AN INCREASING CHANCE OF WINDS INCREASING TO SMALL CRAFT ADVISORY LEVELS BETWEEN SATURDAY AND MONDAY. && .LOX WATCHES/WARNINGS/ADVISORIES... NONE && $$ PUBLIC...KAPLAN AVIATION/MARINE...HALL SYNOPSIS...RM WWW.WEATHER.GOV/LOSANGELES
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NWS LOS ANGELES/OXNARD CA
312 AM PDT THU JUL 9 2015 UPDATED MARINE SECTION .SYNOPSIS... AN AREA OF LOW PRESSURE ALOFT WILL MOVE TOWARDS SOUTHWESTERN CALIFORNIA TODAY BRINING COOLER THAN NORMAL CONDITIONS WITH MOSTLY CLOUDY SKIES WEST OF THE MOUNTAINS. THERE WILL BE A SLIGHT CHANCE OF THUNDERSTORMS IN SOME MOUNTAIN LOCATIONS THIS AFTERNOON AND EVENING. LOW PRESSURE WILL PERSIST OVER THE REGION INTO EARLY NEXT WEEK. THERE WILL CONTINUE TO BE NIGHT THROUGH MORNING LOW CLOUDS FOR COAST AND SOME VALLEYS WITH A WARMING TREND EXPECTED BY MID WEEK AS HIGH PRESSURE BUILDS. && .SHORT TERM (TODAY-SAT)...AN INTERESTING WEATHER PATTERN IS SETTING UP THIS MORNING. A UNSEASONABLE UPPER LEVEL CUTOFF LOW WAS JUST SOUTH OF MONTEREY CALIFORNIA THIS MORNING. THIS UPPER LOW WILL ONLY DROP SOUTH TO SAN LUIS OBISPO COUNTY THIS MORNING BEFORE PUSHING EAST AND FILLING IN BY THIS EVENING. A FEW THUNDERSTORMS WERE ALREADY STARTING TO KICK UP OVER NW KERN COUNTY NEAR THE CORE OF THE UPPER LOW BETWEEN LOST HILLS AND BUTTONWILLOW. THE HRRR MODEL INITIATED WELL AND SHOWED THESE SHOWERS BEING SHORT LIVED AS THEY MOVE TO THE NE. NOT MUCH CONVECTION EXPECTED WITH THE UPPER LOW ITSELF TODAY. HOWEVER BY THIS AFTERNOON...MODELS ARE SUGGESTING SOME INSTABILITY OVER THE MOUNTAINS...WITH THE BEST CHANCE OF THUNDERSTORM POTENTIAL OVER THE VENTURA COUNTY MTNS AND THE ADJACENT EASTERN PORTION OF THE SANTA BARBARA COUNTY MTNS. LATEST MODEL SOUNDINGS AROUND MT BALDY IN L.A. COUNTY WAS INDICATING A FAIRLY STRONG CAP TO INHIBIT THUNDERSTORM DEVELOPMENT. HOWEVER FURTHER WEST THERE WAS ENOUGH COOLING ALOFT ASSOCIATED WITH THE UPPER LOW TO TRIGGER A FEW THUNDERSTORMS. BEST MOISTURE POOL WAS AROUND 700 MB OVER THE VENTURA COUNTY MTNS WHERE WE ARE EXPECTING THE BEST CHANCE FOR ISOLATED THUNDERSTORMS TO DEVELOP THIS AFTERNOON. THE PRECIPITABLE WATERS WILL BE LESS THAN AN INCH. THE COMBINATION OF MODEST PW...AND WESTERLY STEERING WINDS 15 TO 20 MPH WILL HELP STORMS MOVE ALONG MAKING IT DIFFICULT FOR ANY FLASH FLOODING TO OCCUR. THERE COULD BE BRIEF PERIODS OF LOCALLY HEAVY RAIN AT TIMES AROUND THE LOCKWOOD VALLEY AREA WHICH COULD CAUSE SOME LOCALLY FLOODED ROADS. FOR MOST OF THE FORECAST AREA...THE MAIN STORY WILL BE THE VERY DEEP MARINE LAYER OR DEEP (STABLE)MOIST LAYER AS HIGH AS 5000 FT DEEP THIS MORNING. THERE WILL BE ENOUGH LIFT IN THE ATMOSPHERE TO HELP SQUEEZE OUT SOME DRIZZLE JUST ABOUT ANYWHERE WEST OF THE MOUNTAINS THIS MORNING...OR EVEN SOME LIGHT STRATIFORM LIGHT RAIN ACROSS THE ELEVATED VALLEYS AND FOOTHILLS OF LA/VTU COUNTIES WITH LESS THAN A TENTH OF AN INCH OF RAIN POSSIBLE...MAINLY AROUND LA CANADA AND LA CRESCENTA FOOTHILLS. CLOUDS WILL LIKELY LINGER ALL DAY ALONG THE COAST AND REMAIN MOSTLY CLOUDY FOR VALLEYS IN THE MORNING WITH ONLY PARTIAL CLEARING IN THE AFTERNOON. OR...THERE COULD BE A REVERSE CLEARING SITUATION WHERE THE BEACHES CLEAR BY THE EARLY AFTERNOON AND SKIES REMAIN MOSTLY CLOUDY ACROSS VALLEYS AND FOOTHILLS. TODAY WILL BE THE COOLEST DAY OF THE WEEK...WHICH HAS ALREADY BEEN WELL BELOW AVERAGE FOR THIS TIME OF YEAR FROM YESTERDAY`S HIGHS. HIGH TEMPS ACROSS MOST VALLEYS WILL REMAIN IN THE 70S TO AROUND 80 IN THE WARMEST SPOTS. THE ANTELOPE VALLEY WILL ONLY REACH THE LOWER 80S AS WELL. THE NORMAL HIGH FOR LANCASTER THIS TIME OF YEAR IS AROUND 97 DEGREES. BY FRIDAY...IN THE WAKE OF THE UPPER TROUGH MOVING NE...ANOTHER DEEPER BROAD UPPER TROUGH WILL LINGER ACROSS CALIFORNIA THROUGH AT LEAST SATURDAY...WHILE HIGH PRESSURE ALOFT OVER TEXAS WILL BECOME ELONGATED AND NUDGE INTO THE MOST SOUTHERN PORTION OF EASTERN CALIFORNIA. HIGH TEMPS WILL BEGIN TO REBOUND BOTH FRI AND SAT A FEW DEGREES EACH DAY WITH NIGHT THROUGH MORNING LOW CLOUDS CONTINUING ACROSS COAST AND COASTAL VALLEYS. .LONG TERM (SUN-WED)... BOTH THE GFS AND ECMWF ARE IN FAIRLY GOOD AGREEMENT KEEPING A RELATIVELY WEAK UPPER TROUGH OVER MUCH OF CALIFORNIA WHILE THE UPPER LVL RIDGE OVER AZ/EASTERN SOUTHERN CALIFORNIA TRIES TO NUDGE IN UNDER THE TROUGH. BY WEDNESDAY HIGH PRESSURE STARTS TO GET MORE CONTROL OF SOUTHERN CALIFORNIA WHILE THE UPPER TROUGH RETREATS A BIT TO THE NORTH. EXPECT TEMPS TO CLIMB TUE/WED WITH HIGHS LIKELY REACHING THE LOWER TO MID 90S ACROSS INLAND VALLEYS...LOWER MOUNTAIN ELEVATIONS AND THE ANTELOPE VALLEY. THERE WILL CONTINUE TO BE GUSTY SW WINDS ACROSS PORTIONS OF THE ANTELOPE VALLEY...WHILE COAST AND SOME COASTAL VALLEYS WILL CONTINUE WITH NIGHT THROUGH MORNING LOW CLOUDS. THE INVERSION WILL BE SHALLOWER SO VALLEYS SHOULD CLEAR QUICKER WHILE A FEW BEACH CITIES MIGHT FIND IT TOUGH TO CLEAR IN THE AFTERNOON. && .AVIATION...09/0703Z. AT 06Z...THE MARINE LAYER DEPTH AT KLAX WAS BASED AROUND 4300 FEET. THE TOP OF THE INVERSION WAS AROUND 5400 FEET WITH A TEMPERATURE OF 14 DEGREES CELSIUS. MVFR CONDITIONS WILL LIKELY SPREAD INTO MOST COASTAL AND VALLEY TERMINALS THROUGH 08Z. THERE IS A SLIGHT CHANCE OF IFR CONDITIONS IN DRIZZLE BETWEEN 10Z AND 16Z. THERE IS A CHANCE OF MVFR CONDITIONS OR CEILINGS AT OR BELOW 5000 FEET LINGERING THROUGHOUT THURSDAY AFTERNOON. KLAX AND KBUR...MVFR CONDITIONS WILL LIKELY PERSIST THROUGH AT LEAST 21Z. THERE IS A 20 PERCENT CHANCE OF IFR CONDITIONS IN DRIZZLE BETWEEN 10Z AND 16Z. THERE IS A 40 PERCENT CHANCE OF MVFR CONDITIONS OR CEILINGS AT OR BELOW 5000 FEET LINGERING THROUGHOUT THURSDAY AFTERNOON. && .MARINE...09/300 AM. NO SIGNIFICANT WEATHER IS EXPECTED ACROSS THE COASTAL WATERS THROUGH THROUGH FRIDAY NIGHT. THERE IS AN INCREASING CHANCE OF WINDS INCREASING TO SMALL CRAFT ADVISORY LEVELS BETWEEN SATURDAY AND MONDAY. && .LOX WATCHES/WARNINGS/ADVISORIES... NONE && $$ PUBLIC...KAPLAN AVIATION/MARINE...HALL WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
325 AM PDT THU JUL 9 2015 .SYNOPSIS...A LOW PRESSURE SYSTEM WILL MOVE ACROSS THE AREA TODAY AND BRING BELOW AVERAGE TEMPERATURES AND SHOWERS AND THUNDERSTORMS TO THE SIERRA NEVADA. THE LOW WILL MOVE EAST OF THE REGION ON FRIDAY AND A DRY SOUTHWEST FLOW WILL THEN PREVAIL OVER THE WEEKEND AND INTO THE EARLY PART OF NEXT WEEK. TEMPERATURES WILL WARM FRIDAY THROUGH THE WEEKEND...AND DRY CONDITIONS WILL PREVAIL THROUGHOUT THE AREA BY SATURDAY. && .DISCUSSION...IR/WV IMAGERY INDICATING THE UPPER LOW WHICH HAS BEEN SLOWLY MOVING EAST OFF THE CENTRAL CA COAST OVER THE PAST FEW DAYS...IS FINALLY PUSHING INLAND THIS MORNING. THIS HAS BROUGHT ENOUGH INSTABILITY TO PROVIDE FOR A FEW SHOWERS AND ISOLATED THUNDERSTORMS OVER THE SOUTHWESTERN SAN JOAQUIN VALLEY AS WELL AS OVER THE SOUTHERN SIERRA NEVADA. RECENT RUNS OF THE HRRR HAS INDICATED SOME POTENTIAL FOR CONVECTION THIS MORNING...WITH THE SOUTHERN SIERRA NEVADA BEING THE MOST FAVORED AREA. A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS CONTINUES OVERNIGHT FOR THE HIGHER ELEVATIONS OF THE SOUTHERN SIERRA NEVADA AS WELL AS FOR THE PORTIONS OF THE WEST SIDE OF THE SAN JOAQUIN VALLEY. THE LOW HAS ALSO BROUGHT INCREASED ONSHORE FLOW OVER CENTRAL CA RESULTING IN GUSTY WINDS THROUGH THE PASSES OF THE COASTAL RANGE. A WIND ADVISORY REMAINS IN EFFECT FOR THE WEST SIDE OF THE SAN JOAQUIN VALLEY WEST OF THE INTERSTATE 5 CORRIDOR THROUGH 500 AM PDT THIS MORNING WHERE FREQUENT GUSTS ABOVE 35 MPH HAVE BEEN OBSERVED OVERNIGHT. THE HRRR IS INDICATING THE LOW MOVING EAST ACROSS OUR CWFA TODAY AND PROVIDING OUR AREA WITH INCREASED CLOUDS...MOUNTAIN CONVECTION AND COOLER TEMPERATURES AS FORECASTED HIGHS ARE EXPECTED TO BE 7-10 DEGREES BELOW SEASONAL NORMALS IN THE SAN JOAQUIN VALLEY TODAY. THE 06Z WRF IS INDICATING THE LOW WILL OPEN UP AND MOVE EAST OF OUR AREA TONIGHT AND INTO THE GREAT BASIN ON FRIDAY. A WARMING AND DRYING TREND IS EXPECTED TO COMMENCE ON FRIDAY WITH TEMPERATURES TRENDING UPWARD...BUT STILL BELOW SEASONAL NORMALS. SHOWERS AND THUNDERSTORMS WILL BE CONFINED TO THE HIGHER ELEVATIONS OF THE SOUTHERN SIERRA NEVADA ON FRIDAY AS THE PREVAILING AIRMASS BECOMES MORE STABLE. A DRY SOUTHWEST FLOW IS EXPECTED TO PREVAIL ACROSS CENTRAL CA THIS WEEKEND. RISES IN HEIGHTS AND DIURNAL THICKNESSES ACROSS OUR AREA WILL TEMPERATURES TRENDING UPWARD AND RETURNING TO SEASONAL NORMALS BY EARLY NEXT WEEK. RH PROGS ARE INDICATING DRIER AIR AT THE MID/UPPER LAYERS SO OUR AREA SO EXPECT OUR AREA TO BE MOSTLY CLEAR AND FREE OF PRECIPITATION THIS WEEKEND ALTHOUGH A FEW CUMULUS BUILDUPS WILL BE POSSIBLE NEAR THE SIERRA CREST ON SATURDAY AS A RESULT OF SOME LINGERING INSTABILITY. THE MEDIUM RANGE MODELS ARE IN FAIRLY GOOD AGREEMENT THIS MORNING INDICATING CENTRAL CA WILL REMAIN UNDER A DRY SOUTHWEST FLOW FOR MUCH OF NEXT WEEK AS A RESULT OF INTERACTION BETWEEN AN UPPER RIDGE OVER THE SOUTH CENTRAL CONUS AND A BAGGY UPPER TROUGH OFF THE WESTERN CONUS COAST. THIS WILL RESULT IN DRY CONDITIONS AND NEAR SEASONAL TEMPERATURES FOR MONDAY THROUGH THE MIDDLE OF NEXT WEEK. && .AVIATION...AREAS OF MVFR WITH LOCAL IFR AND TERRAIN OBSCURATIONS IN SHOWERS AND THUNDERSTORMS DEVELOPING OVER THE SOUTHERN SIERRA NEVADA THIS MORNING AND CONTINUING THROUGH 06Z FRIDAY. OTHERWISE...VFR CONDITIONS WILL PREVAIL THROUGHOUT THE CENTRAL CA INTERIOR DURING THE NEXT 24 HOURS. && .AIR QUALITY ISSUES...NONE. && .CERTAINTY... THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS MEDIUM. THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM. THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD. CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL INFORMATION AND/OR TO PROVIDE FEEDBACK. && .CLIMATE... RECORDS SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR KFAT 07-09 113:1905 78:1936 81:2008 55:1983 KFAT 07-10 112:2008 81:1974 82:2008 54:1904 KFAT 07-11 110:1961 82:1888 78:2002 52:1974 KBFL 07-09 113:1905 83:1980 84:2008 52:1923 KBFL 07-10 113:1905 82:1936 85:2008 51:1914 KBFL 07-11 110:1961 83:1936 79:2002 51:1906 && .HNX WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 5 AM PDT EARLY THIS MORNING CAZ089-091. && $$ PUBLIC...DS AVN/FW...JEB SYNOPSIS...DS WEATHER.GOV/HANFORD
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
250 AM PDT THU JUL 9 2015 .SYNOPSIS... AN AREA OF LOW PRESSURE ALOFT WILL MOVE TOWARDS SOUTHWESTERN CALIFORNIA TODAY BRINING COOLER THAN NORMAL CONDITIONS WITH MOSTLY CLOUDY SKIES WEST OF THE MOUNTAINS. THERE WILL BE A SLIGHT CHANCE OF THUNDERSTORMS IN SOME MOUNTAIN LOCATIONS THIS AFTERNOON AND EVENING. LOW PRESSURE WILL PERSIST OVER THE REGION INTO EARLY NEXT WEEK. THERE WILL CONTINUE TO BE NIGHT THROUGH MORNING LOW CLOUDS FOR COAST AND SOME VALLEYS WITH A WARMING TREND EXPECTED BY MID WEEK AS HIGH PRESSURE BUILDS. && .SHORT TERM (TODAY-SAT)...AN INTERESTING WEATHER PATTERN IS SETTING UP THIS MORNING. A UNSEASONABLE UPPER LEVEL CUTOFF LOW WAS JUST SOUTH OF MONTEREY CALIFORNIA THIS MORNING. THIS UPPER LOW WILL ONLY DROP SOUTH TO SAN LUIS OBISPO COUNTY THIS MORNING BEFORE PUSHING EAST AND FILLING IN BY THIS EVENING. A FEW SHOWERS WERE ALREADY STARTING TO KICK UP OVER NW KERN COUNTY IN A DIFFLUENT REGION BETWEEN LOST HILLS AND BUTTONWILLOW. THE HRRR MODEL INITIATED WELL AND SHOWED THESE SHOWERS BEING SHORT LIVED AS THEY MOVE TO THE NE. NOT MUCH CONVECTION EXPECTED WITH THE UPPER LOW ITSELF TODAY. HOWEVER BY THIS AFTERNOON...MODELS ARE SUGGESTING SOME INSTABILITY OVER THE MOUNTAINS...WITH THE BEST CHANCE OF THUNDERSTORM POTENTIAL OVER THE VENTURA COUNTY MTNS AND THE ADJACENT EASTERN PORTION OF THE SANTA BARBARA COUNTY MTNS. LATEST MODEL SOUNDINGS AROUND MT BALDY IN L.A. COUNTY WAS INDICATING A FAIRLY STRONG CAP TO INHIBIT THUNDERSTORM DEVELOPMENT. HOWEVER FURTHER WEST THERE WAS ENOUGH COOLING ALOFT ASSOCIATED WITH THE UPPER LOW TO TRIGGER A FEW THUNDERSTORMS. BEST MOISTURE POOL WAS AROUND 700 MB OVER THE VENTURA COUNTY MTNS WHERE WE ARE EXPECTING THE BEST CHANCE FOR ISOLATED THUNDERSTORMS TO DEVELOP THIS AFTERNOON. THE PERCEPTIBLE WATERS WILL BE MODEST AT BEST WITH LESS THAN AN INCH OF AVAILABLE PW TO WORK WITH. THE COMBINATION OF THIS...AND WESTERLY STEERING WINDS 15 TO 20 MPH WILL HELP STORMS MOVE ALONG MAKING IT DIFFICULT FOR ANY FLASH FLOODING TO OCCUR. THERE COULD BE BRIEF PERIODS OF LOCALLY HEAVY RAIN AT TIMES AROUND THE LOCKWOOD VALLEY AREA WHICH COULD CAUSE SOME LOCALLY FLOODED ROADS. FOR MOST OF THE FORECAST AREA...THE MAIN STORY WILL BE THE VERY DEEP MARINE LAYER OR DEEP (STABLE)MOIST LAYER AS HIGH AS 5000 FT DEEP THIS MORNING. THERE WILL BE ENOUGH LIFT IN THE ATMOSPHERE TO HELP SQUEEZE OUT SOME DRIZZLE JUST ABOUT ANYWHERE WEST OF THE MOUNTAINS THIS MORNING...OR EVEN SOME LIGHT STRATIFORM LIGHT RAIN ACROSS THE ELEVATED VALLEYS AND FOOTHILLS OF LA/VTU COUNTIES WITH LESS THAN A TENTH OF AN INCH OF RAIN POSSIBLE...MAINLY AROUND LA CANADA AND LA CRESCENTA FOOTHILLS. CLOUDS WILL LIKELY LINGER ALL DAY ALONG THE COAST AND REMAIN MOSTLY CLOUDY FOR VALLEYS IN THE MORNING WITH ONLY PARTIAL CLEARING IN THE AFTERNOON. OR...THERE COULD BE A REVERSE CLEARING SITUATION WHERE THE BEACHES CLEAR BY THE EARLY AFTERNOON AND SKIES REMAIN MOSTLY CLOUDY ACROSS VALLEYS AND FOOTHILLS. TODAY WILL BE THE COOLEST DAY OF THE WEEK...WHICH HAS ALREADY BEEN WELL BELOW AVERAGE FOR THIS TIME OF YEAR FROM YESTERDAY`S HIGHS. HIGH TEMPS ACROSS MOST VALLEYS WILL REMAIN IN THE 70S TO AROUND 80 IN THE WARMEST SPOTS. THE ANTELOPE VALLEY WILL ONLY REACH THE LOWER 80S AS WELL. THE NORMAL HIGH FOR LANCASTER THIS TIME OF YEAR IS AROUND 97 DEGREES. BY FRIDAY...IN THE WAKE OF THE UPPER TROUGH MOVING NE...ANOTHER DEEPER BROAD UPPER TROUGH WILL LINGER ACROSS CALIFORNIA THROUGH AT LEAST SATURDAY...WHILE HIGH PRESSURE ALOFT OVER TEXAS WILL BECOME ELONGATED AND NUDGE INTO THE MOST SOUTHERN PORTION OF EASTERN CALIFORNIA. HIGH TEMPS WILL BEGIN TO REBOUND BOTH FRI AND SAT A FEW DEGREES EACH DAY WITH NIGHT THROUGH MORNING LOW CLOUDS CONTINUING ACROSS COAST AND COASTAL VALLEYS. .LONG TERM (SUN-WED)... BOTH THE GFS AND ECMWF ARE IN FAIRLY GOOD AGREEMENT KEEPING A RELATIVELY WEAK UPPER TROUGH OVER MUCH OF CALIFORNIA WHILE THE UPPER LVL RIDGE OVER AZ/EASTERN SOUTHERN CALIFORNIA TRIES TO NUDGE IN UNDER THE TROUGH. BY WEDNESDAY HIGH PRESSURE STARTS TO GET MORE CONTROL OF SOUTHERN CALIFORNIA WHILE THE UPPER TROUGH RETREATS A BIT TO THE NORTH. EXPECT TEMPS TO CLIMB TUE/WED WITH HIGHS LIKELY REACHING THE LOWER TO MID 90S ACROSS INLAND VALLEYS...LOWER MOUNTAIN ELEVATIONS AND THE ANTELOPE VALLEY. THERE WILL CONTINUE TO BE GUSTY SW WINDS ACROSS PORTIONS OF THE ANTELOPE VALLEY...WHILE COAST AND SOME COASTAL VALLEYS WILL CONTINUE WITH NIGHT THROUGH MORNING LOW CLOUDS. THE INVERSION WILL BE SHALLOWER SO VALLEYS SHOULD CLEAR QUICKER WHILE A FEW BEACH CITIES MIGHT FIND IT TOUGH TO CLEAR IN THE AFTERNOON. && .AVIATION...09/0703Z. AT 06Z...THE MARINE LAYER DEPTH AT KLAX WAS BASED AROUND 4300 FEET. THE TOP OF THE INVERSION WAS AROUND 5400 FEET WITH A TEMPERATURE OF 14 DEGREES CELSIUS. MVFR CONDITIONS WILL LIKELY SPREAD INTO MOST COASTAL AND VALLEY TERMINALS THROUGH 08Z. THERE IS A SLIGHT CHANCE OF IFR CONDITIONS IN DRIZZLE BETWEEN 10Z AND 16Z. THERE IS A CHANCE OF MVFR CONDITIONS OR CEILINGS AT OR BELOW 5000 FEET LINGERING THROUGHOUT THURSDAY AFTERNOON. KLAX AND KBUR...MVFR CONDITIONS WILL LIKELY PERSIST THROUGH AT LEAST 21Z. THERE IS A 20 PERCENT CHANCE OF IFR CONDITIONS IN DRIZZLE BETWEEN 10Z AND 16Z. THERE IS A 40 PERCENT CHANCE OF MVFR CONDITIONS OR CEILINGS AT OR BELOW 5000 FEET LINGERING THROUGHOUT THURSDAY AFTERNOON. && .MARINE...08/900 PM. EXCEPT FOR LOCAL SMALL CRAFT ADVISORY WINDS IN THE E SBA CHANNEL THIS EVENING...WINDS ARE FORECAST TO REMAIN BELOW SCA IN ALL COASTAL WATERS THROUGH SAT. THERE IS A 60 PERCENT CHANCE OF WINDS INCREASING TO SCA LEVELS IN THE OUTER WATERS SUN AND MON. && .LOX WATCHES/WARNINGS/ADVISORIES... NONE && $$ PUBLIC...KAPLAN AVIATION/MARINE...HALL WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
740 PM MDT FRI JUL 10 2015 .UPDATE... ISSUED AT 740 PM MDT FRI JUL 10 2015 ISOLATED STORMS REMAIN OVER THE HIGHER TERRAIN AND SOUTHERN FOOTHILLS. WILL KEEP LOW POPS IN THE FORECAST THROUGH THE EVENING HOURS FOR THE FRONT RANGE AND WESTWARD. OVER THE EASTERN PLAINS... AIRMASS HAS STABILIZED AND CLOUDS HAVE DISSIPATED. CURRENT FORECAST IS ON TRACK AND WILL ONLY MAKE MINOR CHANGES TO POPS. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 212 PM MDT FRI JUL 10 2015 MODEST AND RATHER DEEP QUASIGEOSTROPHIC SUBSIDENCE IS LIKELY THE MAIN FACTOR LIMITING CONVECTION OVER THE AREA THIS AFTERNOON. LOWER MOISTURE LEVELS AND STABILITY ARE ALSO CONTRIBUTING TO THE MINIMAL ACTIVITY. INDEED GPS MEASURED PRECIPITABLE WATER AT BOULDER IS PRESENTLY ABOUT A QUARTER OF AN INCH LESS THAN 24 HOURS AGO. CONSEQUENTLY HAVE LOWERED POPS FOR TONIGHT ALTHOUGH HAVE NOT ELIMINATED THEM COMPLETELY. WHATEVER DOES MANAGE TO GET GOING DURING THE HEATING OF THE DAY SHOULD DISSIPATE RATHER QUICKLY BY OR SHORTLY AFTER SUNDOWN WITH HRRR RUNS GRADUALLY BACKING AWAY FROM ANY ACTIVITY WHATSOEVER. TOMORROW SHOULD BE A BIT WARMER STILL WITH EVEN LESS CONVECTION THAT TODAY. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 129 PM MDT FRI JUL 10 2015 OVER THE WEEKEND...THE UPPER LEVEL RIDGE WILL SHIFT WESTWARD OVER NORTH TEXAS WITH THE MID LEVELS OVER COLORADO BECOMING INCREASINGLY SUBSIDENT. THE FLOW ALOFT WILL BE SOUTHWESTERLY... WITH MOST OF THE SUBTROPICAL MOISTURE SOUTH AND WEST OF THE CWA. THE COMBINATION OF LESS MOISTURE IN THE LOWER LEVELS AND INCREASED SUBSIDENCE IN THE MID LEVELS WL ALLOW FOR ISOLD COVERAGE AT BEST ON SUNDAY. TEMPERATURES ON SUNDAY WL MAKE IT BACK INTO THE LOWER 90S. FOR MONDAY...THE RIDGE DOES SHIFT TO THE SOUTH A BIT. THE GFS DOES APPEAR TO BRING A WEAK SHORT WAVE ACROSS THE CWA AROUND 00Z TUESDAY. AS A RESULT...MORE CLOUDS WITH A BETTER CHANCE OF TSTMS MONDAY AFTN AND EVNG. ON TUESDAY...A BROAD FLAT RIDGE WILL STRETCH ACROSS THE SRN U.S. WITH A PERSISTENT WEST-SOUTHWESTERLY FLOW OVER COLORADO. SUBTROPICAL MOISTURE WILL REMAIN PREVALENT IN THE MID LEVELS SO ISOLD TO SCT TSTMS IN THE AFTN/EVNG. THE OVERALL PATTERN PERSISTS INTO WEDNESDAY...ALTHOUGH THE LATEST MDL RUN SHOW A DRIER FLOW ALOFT OVER NORTHERN CO. && .AVIATION...(FOR THE TAFS THROUGH 00Z SATURDAY LATE AFTERNOON) ISSUED AT 215 PM MDT FRI JUL 10 2015 ONLY A MINIMAL THREAT OF THUNDERSTORMS AT THE TERMINALS THIS AFTERNOON AND EVENING AND SATURDAY DOES NOT PROMISE MUCH MORE IN THAT DEPARTMENT. WINDS ARE PRETTY LIGHT AND NOT TERRIBLY ORGANIZED THIS AFTERNOON AND SHOULD TRANSITION TO DRAINAGE DURING THE EVENING. DIURNAL WINDS ARE EXPECTED AGAIN SATURDAY AFTERNOON. && .AVIATION...(FOR THE TAFS THROUGH 06Z SATURDAY EVENING) ISSUED AT 740 PM MDT FRI JUL 10 2015 SKIES ARE MOSTLY CLEAR ACROSS THE DENVER AREA. JUST A SLIGHT CHANCE FOR A THUNDERSTORM THROUGH 06Z. WILL KEEP TS OUT OF THE TAFS AND IF ONE APPROACHES WILL AMEND. SOUTHEAST WINDS WILL TURN SOUTHERLY AROUND 06Z. LIGHT WINDS ARE EXPECTED ON SATURDAY WITH DRY CONDITIONS. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...MEIER SHORT TERM...ET LONG TERM...COOPER AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
321 PM MDT THU JUL 9 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 321 PM MDT THU JUL 9 2015 TONIGHT AND FRIDAY...A SOUTHWESTERLY FLOW ALOFT WILL CONTINUE OVER THE REGION. VISIBLE STLT SHOWING SUFFICIENT CLEARING THIS AFTERNOON TO FUEL THUNDERSTORMS. THE LATEST HRRR SHOWS A FAIR AMOUNT OF DEEP CONVECTION DEVELOPING...ESPECIALLY OVER THE PALMER DIVIDE LATE THIS AFTERNOON AND EVENING. WILL INCREASE THE COVERAGE OF SHOWERS AND THUNDERSTORMS IN THOSE AREAS THIS EVENING. A WEAK EMBEDDED DISTURBANCE WILL MAKE ITS WAY ACROSS THE CWA LATE TONIGHT AND FRIDAY MORNING. WL KEEP THE MENTION OF SHOWERS AND THUNDERSTORMS OVERNIGHT AND INTO FRIDAY MORNING. LATEST MESOETA SHOWS GOOD BOUNDARY LAYER RELATIVE HUMIDITIES OVER THE NORTHEAST PLAINS. WL MENTION SOME PATCHY FOG IN THOSE AREAS FM ROUGHLY 09Z- 15Z FRIDAY MORNING. BY FRIDAY AFTERNOON...THE SYSTEM WILL EXIT TO THE NORTHEAST WITH SOME MID LEVEL RIDGING. NAM12 FORECAST SOUNDINGS SHOW GOOD CAPES OVER THE URBAN CORRIDOR AND NORTHEAST PLAINS WITH VALUES OF 1400 TO 2200 J/KG IN THE AFTERNOON. DECENT PW VALUES AS WELL...0.9 TO 1.0 INCHES. BUT NAM12 QG IN THE MID LEVELS SHOWS DECENT DOWNWARD VERTICAL VELOCITIES WHICH MAY KEEP THE AMS CAPPED IN THE AFTERNOON. NOT SURE WHICH WL WIN OUT BUT IT DOES LOOK SUFFICIENT ENUF TO CAP THINGS. FOR NOW WL KEEP SCT COVERAGE IN THE MOUNTAINS...WITH ISOLD COVERAGE OVER MOST OF THE NORTHEAST PLAINS IN THE AFTERNOON. THE STRONGER STORMS COULD STILL PRODUCE HEAVY RAINFALL AND FREQUENT CLOUD TO GROUND LIGHTNING. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 321 PM MDT THU JUL 9 2015 LITTLE CHANGE TO THE LONG TERM FORECAST TODAY. DRIER AIR MOVES IN FROM THE WEST FRIDAY NIGHT AND THEN THE RIDGE OVER TEXAS BUILDS NORTHWARD FOR THE WEEKEND. THERE WILL STILL BE SOME LOW LEVEL MOISTURE AROUND...BUT EVERYTHING ELSE WOULD SUGGEST QUITE LIMITED CONVECTION. STICKING WITH KEEPING ONLY ISOLATED MOUNTAIN STORMS OVER THE WEEKEND. EXPECTING A GRADUAL INCREASE IN MOISTURE AS THE PATTERN DOES NOT CHANGE MUCH IN THE EARLY PART OF THE WEEK. THERE WILL EVENTUALLY BE SOME WEAK WAVES IN THE WESTERLY FLOW...AT LEAST BRINGING A LITTLE LIFT TO HELP MARGINAL CONVECTION AND BRING SOME COOLING. PREVIOUS FORECAST HAS US NEAR 90 DURING THE WEEKEND THEN DROPPING INTO THE 80S WITH SEASONAL POPS BY MID WEEK...AND THAT LOOKS GOOD. && .AVIATION...(FOR THE TAFS THROUGH 00Z FRIDAY LATE AFTERNOON) ISSUED AT 321 PM MDT THU JUL 9 2015 VFR CIGS/VSBYS THROUGH 06Z. IF A THUNDERSTORMS MOVES OVER THE AIRPORTS THEN COULD SEE MVFR CIGS/VSBY RESTRICTIONS WITH THE PASSING STORMS. MAY NEED TO KEEP VCSH IN THE FORECAST OVERNIGHT. AFTER 09Z...POTENTIAL FOR LOW STATUS CLOUDS AND PATCHY FOG DOES EXIST...BUT THE THREAT WILL BE HIGHEST NORTH AND EAST OF THE AIRPORT. SHOULD SEE MORE SUN AND LESS TSTM COVERAGE FRIDAY AFTERNOON. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...COOPER LONG TERM...GIMMESTAD AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
109 PM EDT THU JUL 9 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE ALONG A STALLED COLD FRONT OVER THE DELMARVA REGION TODAY AND TONIGHT. THEN, HIGH PRESSURE WILL MOVE IN FOR FRIDAY THROUGH THE WEEKEND. A WARM FRONT WILL THEN MOVE TO THE NORTH ON MONDAY. MORE UNSETTLED WEATHER IS EXPECTED EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... NO BIG CHANGES WITH THIS ESTF UPDATE. THE MID SHIFT DID AN EXCELLENT JOB DESCRIBING THE THERMODYNAMIC AND KINEMATIC FORCING WITH THIS UPCOMING SYSTEM IN THE SHORT TERM SECTION AND THE 12Z SOUNDINGS SUPPORT THIS THINKING. IMPRESSIVE LLJ AT ILN OF 40 TO 50 KTS WILL SPREAD NORTHEASTWARD THIS AFTERNOON. WHILE THE 500MB TEMPS ARE WARM, ESPECIALLY OVER THE NORTHERN HALF OF OUR CWA, THEY WILL BE COOLING AS WILL 700MB TEMPS (10C POOL OVER US THIS MORNING). WE ARE IN THE FAVORABLE ENTRANCE REGION OF THE 250MB/300MB JET. OUR BIGGEST WHAT IF REMAINS TIMING AS THE CONVECTION SHOULD BE ARRIVING AFTER PEAK HEATING. THE CAVEAT AS MENTIONED IF A COLD POOL FORMS, THE TENDENCY IS FOR THE EVENT TO OCCUR FASTER AND THUS INCREASE OUR SEVERE CHANCES. RIGHT NOW THE SPC ENHANCED OUTLOOK REGION DOES LOOK VERY REASONABLE GIVEN ALL OF THE SHEAR AND BUOYANCY PARAMETERS. WE ARE HEDGING A LITTLE BIT FASTER BASED ON MOST OF THE OVERNIGHT MODELS BRINGING MEASURABLE TO PHL BY 00Z. HAVE NOTICED A COUPLE OF THE LATEST HRRR AND COSPA RUNS ARE SLOWING TSTMS DOWN JUST A TAD. WITH CLEAR SKIES DEVELOPING, WE ARE HOLDING ON TO PREDICTED MAX TEMPS AND THE GAP BETWEEN PREDICTED AND OBSERVED TEMPS (GENERALLY LOWER) IS CLOSING. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/... LOW PRESSURE IS FORECAST TO TRACK EASTWARD ALONG A WARM FRONT NEAR THE NY-PA BORDER. THE GREATEST SYNOPTIC-SCALE LIFT SPREADS INTO THE AREA DURING THE EVENING HOURS WHEN UPPER DIVERGENCE IS ENHANCED IN THE RIGHT ENTRANCE REGION OF AN UPPER-LEVEL JET STREAK AND DPVA FROM THE SHORTWAVE TROUGH ARRIVES. THE UPSTREAM MCS IS EXPECTED TO IMPACT THE AREA MAINLY THIS EVENING. CONVECTIVE-ALLOWING MODELS ARE IN GOOD AGREEMENT, SHOWING A BROKEN LINE OF CONVECTION AHEAD OF A COLD FRONT MOVING THRU THE AREA IN THE 22Z-03Z PERIOD. THERE IS ENOUGH LIFT AND INSTABILITY DEEPER INTO THE WARM SECTOR TO MAINTAIN CONVECTION AFTER SUNSET ALL THE WAY TO THE COAST (BEFORE MOVING OFFSHORE SOMETIME AROUND MIDNIGHT). POPS THIS EVENING ARE HIGHEST ACROSS NORTHEAST PA AND NORTHERN NJ AS CONVECTIVE COVERAGE LOOKS TO BE ENHANCED BY PRESSURE FALLS FROM THE WAVE OF LOW PRESSURE. SPC CONVECTIVE OUTLOOK, THE PRIMARY THREAT IS DAMAGING WINDS FROM WET DOWNBURSTS BUT AN ISOLATED TORNADO IS CERTAINLY POSSIBLE. SLIGHTLY BACKED SURFACE WINDS CLOSER TO THE WARM FRONT WOULD ENHANCE THE TORNADO POTENTIAL A BIT NORTHWEST OF PHILA. HODOGRAPHS DO NOT LOOK PARTICULAR FAVORABLE FOR TORNADOES UNTIL THE EVENING, WHEN A STRONG LOW-LEVEL JET HELPS ENHANCES ENVIRONMENTAL HELICITY CONSIDERABLY. CONVECTION THIS EVENING WILL CERTAINLY BE EFFICIENT RAINFALL PRODUCERS: MODEL SOUNDINGS DURING THE 00Z-06Z PERIOD SHOW SATURATION IN A DEEP 15 KFT DEEP WARM CLOUD LAYER, PWATS 2-2.25 INCHES, AND A FAVORABLE AMOUNT OF CONVECTIVE INSTABILITY (I.E., ENOUGH TO MAINTAIN CONVECTION BUT NOT TOO MUCH TO MAKE IT SUSCEPTIBLE FOR DRY AIR ENTRAINMENT). ASIDE FROM THE 00Z NAM, WHICH IS A SOUTHERN OUTLIER, GUIDANCE HAS PLACED THE AXIS OF HEAVIEST RAIN NEAR THE FRONT TO BE NORTH OF THE CWA. FOR OUR AREA, EXPECT THE DURATION OF HEAVY RAIN TO BE RATHER SHORT AS THESE STORMS WILL BE MOVING EASTWARD AT A STEADY PACE. THIS SHOULD LIMIT THE FLASH FLOOD THREAT A BIT BUT LOCALIZED HEAVY RAINFALL AND FLASH FLOODING IS CERTAINLY A POSSIBILITY. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... LOW PRESSURE WILL BE MOVG AWAY FROM THE AREA AT THE START OF THE EXTENDD PD AND HIGH PRES WILL BE BUILDING IN FROM THE W. THEREFORE, A DRY FRI IS IN STORE AND A NICE WEEKEND AS WELL LOOKS TO BE IN THE CARDS, OR AT LEAST MOST OF THE WEEKEND. THE HIGH WILL GRADUALLY MOVE EWD THRU SAT AND INTO SUN. BOTH THE ECMWF AND CMC ARE DRY THRU 13/00Z MON. THE GFS HAS SOME VERY LOW POPS (DIURNAL SHRA/TSRA) N AND W. SO FOR NOW, WILL JUST CARRY SOME VERY LOW POPS, BUT WOULDN`T BE SURPRISED IF IT WAS COMPLETELY DRY. AFTER 00Z MON, BOTH THE CMC AND ECMWF BRING IN PRECIP WITH A LOW FROM THE W AND A WMFNT. THE GFS IS DRY THROUGH 13/12Z, BUT BRINGS IN SOME PRECIP AFTER 13/12Z. THE EC IS QUITE WET ON MON. THE CMC IS MIDDLE OF THE ROAD AND THE GFS IS DRY. THEN BY TUE, THE GFS IS THE WETTEST MDL,. WITH ANOTHER LOW AND AN APPROACHING CDFNT, WHILE THE ECMWF IS DRY AND THE CMC IS THE COMPROMISE SOLN. SO, WHAT CAN WE DEDUCE FROM THIS? AT LEAST PART OF MON IS LIKELY TO BE WET AND PSBLY MORE. TUE IS VERY UNCERTAIN AND WED AS WELL. THE GFS HAS MORE DIURNAL ACTIVITY ON WED. THE EC HINTS AT SOME BUT IS DRIER. BUT BOTH DAYS COULD STILL BE UNSETTLED. TEMPS LOOK TO BE AT OR A BIT ABV NRML THRU THE PD, BUT DEWPTS SHUD BE COMFORTABLE UNTIL PSBLY TWD THE END OF THE EXTENDD PD. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY, AND SURROUNDING AREAS. 18Z TAF MAINTAINS A HIGH TSRA IMPACT ACROSS OUR TERMINAL AREA LATE THIS AFTERNOON AND EARLY THIS EVENING. OVERALL HIGHEST CONFIDENCE OF IMPACT FOR NORTHWEST TERMINALS AND AIRPORTS WITH LOWEST CONFIDENCE OF IMPACT FOR ANY DELMARVA AIRPORTS SOUTH OF KILG. THROUGH THIS EVENING...TERMINALS START VFR WITH WINDS SLOWING BACKING MORE TO THE SOUTHWEST AND GUSTINESS INCREASING, GETTING CLOSER TO 20 KNOTS. WE CONTINUE A TWO HOUR WINDOW OF STRONG TSRAS AFFECTING ALL OF OUR TERMINALS. MVFR CONDITIONS ARE QUITE LIKELY WITH IFR NOT OUT OF THE QUESTION. STRONG GUSTY WINDS ALONG WITH HEAVY RAIN LIKELY. HIGHEST SVR CHANCE KRDG AND KABE. NOT SURE ABOUT A DOUBLE BARREL (LESSER SECOND) SHOT AND WE HAVE SHOWERS FOR NOW TO COVER THE CHANCE. LATER THIS EVENING, THE CFP IS PREDICTED WITH WINDS BECOMING WEST WITH CONTINUED GUSTINESS. CIGS AND VSBYS SHOULD QUICKLY BECOME VFR. OVERNIGHT...ENOUGH WIND WE BELIEVE TO PREVENT FOG FROM FORMING. SKIES SHOULD BECOME MOSTLY CLEAR, OR AT THE MOST A SCATTERED VFR DECK LINGERING. FRIDAY...VFR NO CIG EXPECTED. NORTHWEST WINDS AVERAGING 10 TO 15 KNOTS. THERE MIGHT BE AN HOUR OR TWO OF GUSTINESS ONCE BETTER MIXING OCCURS DURING THE MORNING. THIS LOOKS MORE LIKELY AT AIRPORTS FARTHER TO THE NORTHEAST, SO NOT INCLUDED WITH THIS PACKAGE. OUTLOOK... FRI AFTERNOON THROUGH SUN...VFR. W TO NW WIND UNDER 10 KT. HIGH CONFIDENCE. LOW CHC POPS FOR SHRA/TSRA MAINLY W ON SUN. SUN NIGHT - MON...MOSTLY VFR. SOME AFTN SHRA/TSRA PSBL. LOW TO MDT CONFIDENCE. && .MARINE... WINDS AND SEAS EXPECTED TO REMAIN BELOW SCA CRITERIA TODAY. THE MAIN WX-CONCERN ON THE WATERS TODAY WILL BE TSTMS. AN ISOLATED STORM MAY DEVELOP DURING THE AFTERNOON BUT THE BEST CHANCE FOR STORMS WILL BE THIS EVENING AHEAD OF A COLD FRONT. LOCALLY STRONG WINDS ARE POSSIBLE. OUTLOOK... FRI THROUGH MON...NO MARINE FLAGS ARE ANTICIPATED THROUGH THIS PD. SEAS WILL ACTUALLY DECREASE AS LOW PRES ON FRI MOVES AWAY FROM THE AREA AND HIGH PRES BUILDS IN FOR THE REMAINDER OF THE PD. WIND GUSTS WILL GENLY BE 15 TO 20 KT ON FRI, THEN 10-15 KT THRU SUN, BEFORE APPROACHING 20 KT AGAIN SUN NIGHT INTO MON. DIRECTIONS WILL BE OUT OF THE N THRU SAT NIGHT BEFORE SHIFTING TO THE SW TO W SAT NIGHT THU MON. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...NIERENBERG NEAR TERM...GIGI SHORT TERM...KLEIN LONG TERM...NIERENBERG AVIATION...GIGI/NIERENBERG MARINE...KLEIN/NIERENBERG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1224 PM EDT THU JUL 9 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE ALONG A STALLED COLD FRONT OVER THE DELMARVA REGION TODAY AND TONIGHT. THEN, HIGH PRESSURE WILL MOVE IN FOR FRIDAY THROUGH THE WEEKEND. A WARM FRONT WILL THEN MOVE TO THE NORTH ON MONDAY. MORE UNSETTLED WEATHER IS EXPECTED EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... NO BIG CHANGES WITH THIS ESTF UPDATE. THE MID SHIFT DID AN EXCELLENT JOB DESCRIBING THE THERMODYNAMIC AND KINEMATIC FORCING WITH THIS UPCOMING SYSTEM IN THE SHORT TERM SECTION AND THE 12Z SOUNDINGS SUPPORT THIS THINKING. IMPRESSIVE LLJ AT ILN OF 40 TO 50 KTS WILL SPREAD NORTHEASTWARD THIS AFTERNOON. WHILE THE 500MB TEMPS ARE WARM, ESPECIALLY OVER THE NORTHERN HALF OF OUR CWA, THEY WILL BE COOLING AS WILL 700MB TEMPS (10C POOL OVER US THIS MORNING). WE ARE IN THE FAVORABLE ENTRANCE REGION OF THE 250MB/300MB JET. OUR BIGGEST WHAT IF REMAINS TIMING AS THE CONVECTION SHOULD BE ARRIVING AFTER PEAK HEATING. THE CAVEAT AS MENTIONED IF A COLD POOL FORMS, THE TENDENCY IS FOR THE EVENT TO OCCUR FASTER AND THUS INCREASE OUR SEVERE CHANCES. RIGHT NOW THE SPC ENHANCED OUTLOOK REGION DOES LOOK VERY REASONABLE GIVEN ALL OF THE SHEAR AND BUOYANCY PARAMETERS. WE ARE HEDGING A LITTLE BIT FASTER BASED ON MOST OF THE OVERNIGHT MODELS BRINGING MEASURABLE TO PHL BY 00Z. HAVE NOTICED A COUPLE OF THE LATEST HRRR AND COSPA RUNS ARE SLOWING TSTMS DOWN JUST A TAD. WITH CLEAR SKIES DEVELOPING, WE ARE HOLDING ON TO PREDICTED MAX TEMPS AND THE GAP BETWEEN PREDICTED AND OBSERVED TEMPS (GENERALLY LOWER) IS CLOSING. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/... LOW PRESSURE IS FORECAST TO TRACK EASTWARD ALONG A WARM FRONT NEAR THE NY-PA BORDER. THE GREATEST SYNOPTIC-SCALE LIFT SPREADS INTO THE AREA DURING THE EVENING HOURS WHEN UPPER DIVERGENCE IS ENHANCED IN THE RIGHT ENTRANCE REGION OF AN UPPER-LEVEL JET STREAK AND DPVA FROM THE SHORTWAVE TROUGH ARRIVES. THE UPSTREAM MCS IS EXPECTED TO IMPACT THE AREA MAINLY THIS EVENING. CONVECTIVE-ALLOWING MODELS ARE IN GOOD AGREEMENT, SHOWING A BROKEN LINE OF CONVECTION AHEAD OF A COLD FRONT MOVING THRU THE AREA IN THE 22Z-03Z PERIOD. THERE IS ENOUGH LIFT AND INSTABILITY DEEPER INTO THE WARM SECTOR TO MAINTAIN CONVECTION AFTER SUNSET ALL THE WAY TO THE COAST (BEFORE MOVING OFFSHORE SOMETIME AROUND MIDNIGHT). POPS THIS EVENING ARE HIGHEST ACROSS NORTHEAST PA AND NORTHERN NJ AS CONVECTIVE COVERAGE LOOKS TO BE ENHANCED BY PRESSURE FALLS FROM THE WAVE OF LOW PRESSURE. SPC CONVECTIVE OUTLOOK, THE PRIMARY THREAT IS DAMAGING WINDS FROM WET DOWNBURSTS BUT AN ISOLATED TORNADO IS CERTAINLY POSSIBLE. SLIGHTLY BACKED SURFACE WINDS CLOSER TO THE WARM FRONT WOULD ENHANCE THE TORNADO POTENTIAL A BIT NORTHWEST OF PHILA. HODOGRAPHS DO NOT LOOK PARTICULAR FAVORABLE FOR TORNADOES UNTIL THE EVENING, WHEN A STRONG LOW-LEVEL JET HELPS ENHANCES ENVIRONMENTAL HELICITY CONSIDERABLY. CONVECTION THIS EVENING WILL CERTAINLY BE EFFICIENT RAINFALL PRODUCERS: MODEL SOUNDINGS DURING THE 00Z-06Z PERIOD SHOW SATURATION IN A DEEP 15 KFT DEEP WARM CLOUD LAYER, PWATS 2-2.25 INCHES, AND A FAVORABLE AMOUNT OF CONVECTIVE INSTABILITY (I.E., ENOUGH TO MAINTAIN CONVECTION BUT NOT TOO MUCH TO MAKE IT SUSCEPTIBLE FOR DRY AIR ENTRAINMENT). ASIDE FROM THE 00Z NAM, WHICH IS A SOUTHERN OUTLIER, GUIDANCE HAS PLACED THE AXIS OF HEAVIEST RAIN NEAR THE FRONT TO BE NORTH OF THE CWA. FOR OUR AREA, EXPECT THE DURATION OF HEAVY RAIN TO BE RATHER SHORT AS THESE STORMS WILL BE MOVING EASTWARD AT A STEADY PACE. THIS SHOULD LIMIT THE FLASH FLOOD THREAT A BIT BUT LOCALIZED HEAVY RAINFALL AND FLASH FLOODING IS CERTAINLY A POSSIBILITY. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... LOW PRESSURE WILL BE MOVG AWAY FROM THE AREA AT THE START OF THE EXTENDD PD AND HIGH PRES WILL BE BUILDING IN FROM THE W. THEREFORE, A DRY FRI IS IN STORE AND A NICE WEEKEND AS WELL LOOKS TO BE IN THE CARDS, OR AT LEAST MOST OF THE WEEKEND. THE HIGH WILL GRADUALLY MOVE EWD THRU SAT AND INTO SUN. BOTH THE ECMWF AND CMC ARE DRY THRU 13/00Z MON. THE GFS HAS SOME VERY LOW POPS (DIURNAL SHRA/TSRA) N AND W. SO FOR NOW, WILL JUST CARRY SOME VERY LOW POPS, BUT WOULDN`T BE SURPRISED IF IT WAS COMPLETELY DRY. AFTER 00Z MON, BOTH THE CMC AND ECMWF BRING IN PRECIP WITH A LOW FROM THE W AND A WMFNT. THE GFS IS DRY THROUGH 13/12Z, BUT BRINGS IN SOME PRECIP AFTER 13/12Z. THE EC IS QUITE WET ON MON. THE CMC IS MIDDLE OF THE ROAD AND THE GFS IS DRY. THEN BY TUE, THE GFS IS THE WETTEST MDL,. WITH ANOTHER LOW AND AN APPROACHING CDFNT, WHILE THE ECMWF IS DRY AND THE CMC IS THE COMPROMISE SOLN. SO, WHAT CAN WE DEDUCE FROM THIS? AT LEAST PART OF MON IS LIKELY TO BE WET AND PSBLY MORE. TUE IS VERY UNCERTAIN AND WED AS WELL. THE GFS HAS MORE DIURNAL ACTIVITY ON WED. THE EC HINTS AT SOME BUT IS DRIER. BUT BOTH DAYS COULD STILL BE UNSETTLED. TEMPS LOOK TO BE AT OR A BIT ABV NRML THRU THE PD, BUT DEWPTS SHUD BE COMFORTABLE UNTIL PSBLY TWD THE END OF THE EXTENDD PD. && .AVIATION /16Z THURSDAY THROUGH MONDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY, AND SURROUNDING AREAS. EXPECT VFR LATE THIS MORNING AND AFTERNOON AT ALL TAF SITES AND A LIGHT WIND. ADDED A 2-HR TSRA TEMPO GROUP IN THE 00Z TAFS FOR EACH TAF SITE LATE THIS AFTERNOON AND THIS EVENING WHEN THE BEST CHANCE OF STORMS ARE EXPECTED. THE TIMING WILL LIKELY BE REFINED AS WE GET CLOSER TO THE EVENT BUT OVERALL EXPECT A SLIGHTLY LATER TIMING OF STORMS TODAY THAN USUAL. WE WILL ALSO BE ABLE TO BETTER HIGHLIGHT THE IMPACT FROM VSBYS AND WINDS ONCE WE ARE ABLE TO OBTAIN MORE CERTAINTY IN TIMING AND INTENSITY OF STORMS. S-SW WINDS INCREASE THIS EVENING, BEFORE A WIND SHIFT OUT OF THE WEST AND NORTHWEST OCCURS BEHIND A COLD FRONT LATE THIS EVENING/ OVERNIGHT. OUTLOOK... FRI THROUGH SUN...VFR. W TO NW WIND UNDER 10 KT. HIGH CONFIDENCE. LOW CHC POPS FOR SHRA/TSRA MAINLY W ON SUN. SUN NIGHT - MON...MOSTLY VFR. SOME AFTN SHRA/TSRA PSBL. LOW TO MDT CONFIDENCE. && .MARINE... WINDS AND SEAS EXPECTED TO REMAIN BELOW SCA CRITERIA TODAY. THE MAIN WX-CONCERN ON THE WATERS TODAY WILL BE TSTMS. AN ISOLATED STORM MAY DEVELOP DURING THE AFTERNOON BUT THE BEST CHANCE FOR STORMS WILL BE THIS EVENING AHEAD OF A COLD FRONT. LOCALLY STRONG WINDS ARE POSSIBLE. OUTLOOK... FRI THROUGH MON...NO MARINE FLAGS ARE ANTICIPATED THROUGH THIS PD. SEAS WILL ACTUALLY DECREASE AS LOW PRES ON FRI MOVES AWAY FROM THE AREA AND HIGH PRES BUILDS IN FOR THE REMAINDER OF THE PD. WIND GUSTS WILL GENLY BE 15 TO 20 KT ON FRI, THEN 10-15 KT THRU SUN, BEFORE APPROACHING 20 KT AGAIN SUN NIGHT INTO MON. DIRECTIONS WILL BE OUT OF THE N THRU SAT NIGHT BEFORE SHIFTING TO THE SW TO W SAT NIGHT THU MON. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...NIERENBERG NEAR TERM...GIGI SHORT TERM...KLEIN LONG TERM...NIERENBERG AVIATION...KLEIN/NIERENBERG MARINE...KLEIN/NIERENBERG
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
851 PM EDT FRI JUL 10 2015 .UPDATE... 00Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS TWO DISTINCT UPPER LEVEL CHANNELS ARRIVING FROM THE PACIFIC OVER NORTH AMERICA. THE FIRST IS RIDING WELL TO THE NORTH INTO BRITISH COLUMBIA OVER TOP A BROAD LONGWAVE TROUGH THROUGH THE INTER-MOUNTAIN WEST. THE SECOND CHANNEL IS ARRIVING OVER THE BAJA REGION AND THEN NORTHWESTWARD INTO THE CENTRAL PLAINS. SOUTH OF THIS FLOW...A BROAD WEST TO EAST ELONGATED UPPER RIDGE IS IN CONTROL OF THE NORTHERN GULF OF MEXICO...SOUTHEAST CONUS/FL PENINSULA. GENERAL SUBSIDENCE UNDER THIS RIDGE IS PROVIDING A STEADY FLOW OF DRY MID/UPPER LEVEL AIR OVER THE NORTHERN/CENTRAL FL PENINSULA FROM THE ATLANTIC. THIS DRIER AIR ALOFT HELPED TO KEEP THE OVERALL COVERAGE OF THUNDERSTORMS DOWN TODAY. WE DEFINITELY STILL SAW SCATTERED UPDRAFTS OVERCOME THE NEGATIVE THERMODYNAMIC ENVIRONMENT ALOFT...BUT THE ACTIVITY WAS NOT AS INTENSE OR WIDESPREAD AS PREVIOUS DAYS. EXPECT MORE OF THE SAME FOR SATURDAY...WITH PERHAPS EVEN A BIT LESS ACTIVITY THAN WAS SEEN TODAY. THE DRY AIR ALOFT WAS SAMPLED QUITE WELL BY THE 00Z KTBW SOUNDING...SHOWING A "V" CONFIGURATION ABOVE 700MB. AS WOULD BE EXPECTED UNDER A LARGE UPPER RIDGE...THE LAPSE RATES IN THE MID- LEVELS ARE ALSO ON THE WEAKER SIDE...WHICH AIDED IN KEEPING THE INTENSITY OF THE STORMS TODAY DOWN. THE MOST ACTIVE STORMS AS OF 830 PM ARE OVER LEVY COUNTY...AND EXPECT THESE TO PUSH OFFSHORE BY AROUND 02Z. EAST COAST AND WEST COAST SEA BREEZE BOUNDARIES ARE NOW COLLIDING ALONG THE I-75 CORRIDOR FURTHER TO THE SOUTH. ANYTIME YOU SEE THIS KIND OF DEFINED BOUNDARY COLLISION...A FEW ADDITIONAL LATE EVENING STORMS CAN NOT BE RULED OUT...EVEN WITH THE LESS THAN FAVORABLE CONDITIONS ALOFT. HOWEVER...SO FAR...WE ARE NOT SEEING MUCH...AND JUST HAVE 30% POPS IN THE GRIDS THROUGH 03Z FROM I-75 WESTWARD TO THE COAST. END ALL ACTIVITY FOR THE LAND MASS AFTER 03Z WITH A GENERALLY DRY AND QUIET REST OF THE OVERNIGHT. SATURDAY WILL BE VERY SIMILAR TO FRIDAY...WITH A SIMILAR SYNOPTIC SETUP. WEAK PRESSURE GRADIENT WILL ONLY SLIGHTLY FAVOR THE WEST- COAST SEA BREEZE FOR CONVECTION...HOWEVER AS MENTIONED ABOVE...THE THERMODYNAMIC ENVIRONMENT ALOFT IS NOT FAVORABLE TOWARD DEEP CONVECTION...WITH PLENTY OF DRY AIR ABOVE 700MB...AND MEAGER LAPSE RATES IN THE MID-LEVELS. A FEW STORMS HERE AND THERE WILL BE ABLE TO ROOT THEMSELVES...BUT WILL DESCRIBE THE COVERAGE GENERALLY AS WIDELY SCATTERED. IF ANY PART OF THE FORECAST AREA WOULD BE FAVORED FOR A BIT MORE CONVECTIVE POTENTIAL IT WILL BE THE NATURE COAST...WHERE SOME MOISTURE IS SHOWN BY A FEW OF THE MODEL MEMBERS TO BEGIN ARRIVING FROM THE NORTH BY THE END OF THE DAY. GFS/NAM DO BOTH SHOW MID-LEVEL TO SURFACE THETAE DIFFERENCE SATURDAY AFTERNOON BETWEEN 20-25K. THESE VALUES...OBVIOUSLY CONDITIONAL ON CONVECTION...HAVE BEEN SHOWN IN SEVERAL STUDIES ACROSS THE SOUTHEASTERN CONUS TO PROVIDE A MORE FAVORABLE ENVIRONMENT FOR THE FORMATION OF WET MICROBURSTS. SO THE STORMS THAT WE DO SEE MIGHT VERY WELL HAVE AN ENHANCED THREAT FOR STRONG WIND GUSTS. && .AVIATION... JUST THE OUTSIDE CHANCE OF AN ISOLATED STORM BEFORE 03Z AT THE TERMINALS...BUT OTHERWISE WILL SEE VFR CONDITIONS PREVAIL THROUGH MUCH...IF NOT ALL OF THE TAF PERIOD. CONVECTIVE COVERAGE SHOULD BE BELOW CLIMO FOR MID JULY ON SATURDAY...WITH ISOLATED TO WIDELY SCATTERED STORMS. WILL MENTION VCTS FOR NOW AFTER 18-19Z...HOWEVER BEST CHANCES FOR LATER DAY STORMS CURRENTLY APPEAR TO EXIST TO THE NORTH OF THE FORECAST TERMINALS ACROSS THE NATURE COAST. && .MARINE... NO SIGNIFICANT MARINE CONCERNS THROUGH THE UPCOMING WEEKEND OTHER THAN TYPICAL SCATTERED THUNDERSTORMS. WINDS AND SEAS WILL REMAIN BELOW HEADLINE CRITERIA...WITH FLOW TURNING WEAKLY ONSHORE EACH AFTERNOON WITH SEA BREEZE FORMATION. && .PRELIMINARY POINT TEMPS/POPS... TPA 78 93 79 93 / 30 30 20 30 FMY 76 94 76 94 / 20 20 10 30 GIF 76 96 76 95 / 10 20 10 50 SRQ 77 90 78 92 / 30 20 20 30 BKV 74 94 74 95 / 20 30 20 40 SPG 79 93 80 92 / 30 20 20 30 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...NONE. && $$ UPDATE/AVIATION/MARINE...MROCZKA
AREA FORECAST DISCUSSION
NWS LINCOLN IL
946 PM CDT FRI JUL 10 2015 .UPDATE... ISSUED AT 942 PM CDT FRI JUL 10 2015 HIGH PRESSURE RIDGE OVER THE REGION RESULTING IN CALM WINDS FOR THE EVENING SO FAR. ALTHOUGH THE DWPTS ARE STILL IN THE 60S FOR MANY LOCATIONS, THE PERSISTENT CLOUD COVER IS KEEPING THE TEMPS FROM DROPPING QUICKLY. STORMS TO THE SW ARE PART OF AN UPPER WAVE THAT WILL BE INCREASING PRECIPITATION CHANCES TOWARDS THE MORNING HOURS, BUT NOT INCREASING THE THREAT TOO MUCH UNTIL WELL AFTER MIDNIGHT. SO FAR, THE FORECAST IS GOING WELL AND NO UPDATES ARE ANTICIPATED AT THIS TIME. && .SHORT TERM...(TONIGHT) ISSUED AT 245 PM CDT FRI JUL 10 2015 LOW CLOUD DECK FINALLY EXITING EAST CENTRAL ILLINOIS BUT IS SLOWER TO CLEAR AREAS SOUTH OF I-70...WHERE THE CLOUDS ARE MORE IN A WEST- EAST CONFIGURATION. DIURNAL CUMULUS IS COVERING THE REMAINDER OF THE FORECAST AREA. ALREADY SEEING AN INCREASE IN MID AND HIGH CLOUDS FROM THE WEST AHEAD OF SOME CONVECTION ACROSS THE PLAINS... AFFILIATED WITH AN UPPER WAVE CURRENTLY TRACKING ACROSS KANSAS. MAIN QUESTION FOR TONIGHT WILL BE THE TRACKING OF THIS CONVECTION. THE UPPER WAVE WILL BE MOVING NORTHEAST ALONG THE TOP OF SOME RIDGING THAT IS BUILDING ACROSS THE MISSISSIPPI VALLEY. HIGHER RESOLUTION MODELS...AS WELL AS SYNOPTIC MODELS SUCH AS THE NAM AND ECMWF...ARE FOCUSING THE BULK OF IT JUST TO OUR WEST...SPREADING INTO AREAS NORTHWEST OF THE ILLINOIS RIVER AFTER ABOUT 3 AM. MEANWHILE...THE GFS ONLY HINTS AT SOME LIGHT SHOWERS IN THE EXTREME SOUTHWEST CWA TOWARD SUNRISE. HAVE THUS CONCENTRATED THE HIGHEST RAIN CHANCES ACROSS WEST CENTRAL ILLINOIS MAINLY FROM ABOUT PEORIA- SPRINGFIELD WESTWARD. .LONG TERM...(SATURDAY THROUGH FRIDAY) ISSUED AT 245 PM CDT FRI JUL 10 2015 TIMING OF THUNDERSTORM ACTIVITY...AT LEAST INTO EARLY NEXT WEEK...IS THE MAIN FORECAST CHALLENGE AS WE WILL BE POSITIONED ALONG THE SOUTHERN PERIPHERY OF THE STRONGER FLOW ALOFT AS UPPER LEVEL RIDGING BUILDS OVER THE SOUTHERN PLAINS. THIS IS GENERALLY A VERY FAVORABLE LOCATION FOR NOCTURNAL THUNDERSTORMS TO OCCUR...DEPENDING ON BOUNDARY LOCATION AND ORIENTATION OF THE LOW LEVEL JET. THE CONVECTION THAT IS EXPECTED TO DEVELOP TO OUR WEST AND NORTHWEST LATE TONIGHT WILL SPREAD EAST AND SOUTHEAST DURING SATURDAY MORNING WITH OUR NORTH THE MORE FAVORED LOCATION FOR SCATTERED SHOWERS AND THUNDERSTORMS. MODELS INDICATING THE LOW LEVEL JET WILL STILL BE IN POSITION TO CONTINUE TO FEED HIGH THETA-E AIR NORTHEAST INTO THE BACKSIDE OF THE MCS WHICH MAY CONTINUE THE STORM ACTIVITY OVER PARTS OF WEST CENTRAL ILLINOIS INTO THE AFTERNOON HOURS. ANOTHER ROUND OF CONVECTION IS THEN EXPECTED TO DEVELOP LATE SATURDAY NIGHT INTO SUNDAY AND AGAIN...DEPENDING ON WHAT THE CONVECTION THAT OCCURS SATURDAY DOES TO THE BOUNDARY LOCATION...WILL ULTIMATELY DECIDE WHERE THE NEW CONVECTION FORMS OVERNIGHT SATURDAY INTO SUNDAY. THE MORE FAVORED LOCATIONS WILL BE ACROSS THE NORTH AND EAST AS UPPER LEVEL HEIGHTS AND WARMING TEMPERATURES ALOFT SHIFT THE GREATER RAIN THREAT TO OUR NORTH BY LATER SUNDAY. AFTER THAT...CONFIDENCE REALLY DROPS OFF WITH RESPECT TO COVERAGE AND PLACEMENT OF THE GREATER THUNDERSTORM CHANCES LATE SUNDAY NIGHT INTO MONDAY. MOST MODELS SHOWING EXTREME INSTABILITY LOCATED OVER OUR AREA WITH MID LEVEL LAPSE RATES OF 8+ DGREES/KM...BUT 700 MB TEMPS WARM TO BETWEEN +12 TO +14 DEGREES C WHICH MAY TEND TO SUPPRESS THE STRONGER AND MORE PERSISTENT UPDRAFTS. THE LATEST ECMWF DOES SHIFT A MORE SUBSTANTIAL SHORTWAVE SOUTHEAST INTO THE LOWER GREAT LAKES BY TUESDAY WHICH SHOULD BRING A COOL FRONT SOUTHEAST ACROSS THE AREA...WHICH MAY BRING A BREAK FROM THE DAILY CHANCES FOR THUNDERSTORMS MIDWEEK. HOWEVER...WE HAVE SEEN THE MEDIUM RANGE MODELS TEND TO OVERAMPLIFY THESE SOUTHEASTWARD MOVING TROFS INTO THE LAKES RESULTING IN A MUCH TOO AGGRESSIVE PUSH TO THE COLD FRONT INTO THE OHIO VALLEY WITH THE ULTIMATE FRONTAL LOCATION MUCH FURTHER NORTH. WILL NEED TO SEE A BIT MORE CONSISTENCY WITH THE UPPER PATTERN FORECAST FOR THE MIDDLE OF NEXT WEEK BEFORE MAKING ANY SIGNIFICANT CHANGES TO THE EXTENDED FORECAST. UNTIL THEN... LITTLE CHANGE FROM WHAT WE HAD IN THE FORECAST EARLIER...VERY WARM AND HUMID WITH DAILY CHANCES FOR SHOWERS AND STORMS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 658 PM CDT FRI JUL 10 2015 NOT MUCH OF A SHIFT IN THE FORECAST. SCATTERED LOW AND BKN CIRRUS THROUGH THE EVENING. STORM SYSTEM MOVING THROUGH THE REGION BRINGING SHOWERS AND THUNDERSTORMS TO THE AREA AFTER MIDNIGHT. PREV FORECAST WAS MUCH FURTHER NORTH WITH THE SHOWERS AND THUNDERSTORMS, HOWEVER THE MORE RECENT HRRR AND NAM ARE BOTH IMPACTING THE MAJORITY OF THE TERMINALS THROUGH MIDDAY TOMORROW. HAVE TRIED TO TIME BEST CHANCES WITH VC, KEEPING THE TS IN THE SHORTER RANGE, ESP WITH THE LACK OF SIGNIF THUNDER IN MUCH OF THE PRECIP ACTIVITY SW OF THE OFFICE. CONCERN FOR VIS REDUCTION MAY WORK INTO THE NEXT FORECAST IN BMI/CMI REGION IF THE PRECIP IS A BIT SLOWER TO THE AREA. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...HJS SHORT TERM...GEELHART LONG TERM...SMITH AVIATION...HJS
AREA FORECAST DISCUSSION
NWS LINCOLN IL
720 PM CDT FRI JUL 10 2015 .SHORT TERM...(TONIGHT) ISSUED AT 245 PM CDT FRI JUL 10 2015 LOW CLOUD DECK FINALLY EXITING EAST CENTRAL ILLINOIS BUT IS SLOWER TO CLEAR AREAS SOUTH OF I-70...WHERE THE CLOUDS ARE MORE IN A WEST- EAST CONFIGURATION. DIURNAL CUMULUS IS COVERING THE REMAINDER OF THE FORECAST AREA. ALREADY SEEING AN INCREASE IN MID AND HIGH CLOUDS FROM THE WEST AHEAD OF SOME CONVECTION ACROSS THE PLAINS... AFFILIATED WITH AN UPPER WAVE CURRENTLY TRACKING ACROSS KANSAS. MAIN QUESTION FOR TONIGHT WILL BE THE TRACKING OF THIS CONVECTION. THE UPPER WAVE WILL BE MOVING NORTHEAST ALONG THE TOP OF SOME RIDGING THAT IS BUILDING ACROSS THE MISSISSIPPI VALLEY. HIGHER RESOLUTION MODELS...AS WELL AS SYNOPTIC MODELS SUCH AS THE NAM AND ECMWF...ARE FOCUSING THE BULK OF IT JUST TO OUR WEST...SPREADING INTO AREAS NORTHWEST OF THE ILLINOIS RIVER AFTER ABOUT 3 AM. MEANWHILE...THE GFS ONLY HINTS AT SOME LIGHT SHOWERS IN THE EXTREME SOUTHWEST CWA TOWARD SUNRISE. HAVE THUS CONCENTRATED THE HIGHEST RAIN CHANCES ACROSS WEST CENTRAL ILLINOIS MAINLY FROM ABOUT PEORIA- SPRINGFIELD WESTWARD. .LONG TERM...(SATURDAY THROUGH FRIDAY) ISSUED AT 245 PM CDT FRI JUL 10 2015 TIMING OF THUNDERSTORM ACTIVITY...AT LEAST INTO EARLY NEXT WEEK...IS THE MAIN FORECAST CHALLENGE AS WE WILL BE POSITIONED ALONG THE SOUTHERN PERIPHERY OF THE STRONGER FLOW ALOFT AS UPPER LEVEL RIDGING BUILDS OVER THE SOUTHERN PLAINS. THIS IS GENERALLY A VERY FAVORABLE LOCATION FOR NOCTURNAL THUNDERSTORMS TO OCCUR...DEPENDING ON BOUNDARY LOCATION AND ORIENTATION OF THE LOW LEVEL JET. THE CONVECTION THAT IS EXPECTED TO DEVELOP TO OUR WEST AND NORTHWEST LATE TONIGHT WILL SPREAD EAST AND SOUTHEAST DURING SATURDAY MORNING WITH OUR NORTH THE MORE FAVORED LOCATION FOR SCATTERED SHOWERS AND THUNDERSTORMS. MODELS INDICATING THE LOW LEVEL JET WILL STILL BE IN POSITION TO CONTINUE TO FEED HIGH THETA-E AIR NORTHEAST INTO THE BACKSIDE OF THE MCS WHICH MAY CONTINUE THE STORM ACTIVITY OVER PARTS OF WEST CENTRAL ILLINOIS INTO THE AFTERNOON HOURS. ANOTHER ROUND OF CONVECTION IS THEN EXPECTED TO DEVELOP LATE SATURDAY NIGHT INTO SUNDAY AND AGAIN...DEPENDING ON WHAT THE CONVECTION THAT OCCURS SATURDAY DOES TO THE BOUNDARY LOCATION...WILL ULTIMATELY DECIDE WHERE THE NEW CONVECTION FORMS OVERNIGHT SATURDAY INTO SUNDAY. THE MORE FAVORED LOCATIONS WILL BE ACROSS THE NORTH AND EAST AS UPPER LEVEL HEIGHTS AND WARMING TEMPERATURES ALOFT SHIFT THE GREATER RAIN THREAT TO OUR NORTH BY LATER SUNDAY. AFTER THAT...CONFIDENCE REALLY DROPS OFF WITH RESPECT TO COVERAGE AND PLACEMENT OF THE GREATER THUNDERSTORM CHANCES LATE SUNDAY NIGHT INTO MONDAY. MOST MODELS SHOWING EXTREME INSTABILITY LOCATED OVER OUR AREA WITH MID LEVEL LAPSE RATES OF 8+ DGREES/KM...BUT 700 MB TEMPS WARM TO BETWEEN +12 TO +14 DEGREES C WHICH MAY TEND TO SUPPRESS THE STRONGER AND MORE PERSISTENT UPDRAFTS. THE LATEST ECMWF DOES SHIFT A MORE SUBSTANTIAL SHORTWAVE SOUTHEAST INTO THE LOWER GREAT LAKES BY TUESDAY WHICH SHOULD BRING A COOL FRONT SOUTHEAST ACROSS THE AREA...WHICH MAY BRING A BREAK FROM THE DAILY CHANCES FOR THUNDERSTORMS MIDWEEK. HOWEVER...WE HAVE SEEN THE MEDIUM RANGE MODELS TEND TO OVERAMPLIFY THESE SOUTHEASTWARD MOVING TROFS INTO THE LAKES RESULTING IN A MUCH TOO AGGRESSIVE PUSH TO THE COLD FRONT INTO THE OHIO VALLEY WITH THE ULTIMATE FRONTAL LOCATION MUCH FURTHER NORTH. WILL NEED TO SEE A BIT MORE CONSISTENCY WITH THE UPPER PATTERN FORECAST FOR THE MIDDLE OF NEXT WEEK BEFORE MAKING ANY SIGNIFICANT CHANGES TO THE EXTENDED FORECAST. UNTIL THEN... LITTLE CHANGE FROM WHAT WE HAD IN THE FORECAST EARLIER...VERY WARM AND HUMID WITH DAILY CHANCES FOR SHOWERS AND STORMS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 658 PM CDT FRI JUL 10 2015 NOT MUCH OF A SHIFT IN THE FORECAST. SCATTERED LOW AND BKN CIRRUS THROUGH THE EVENING. STORM SYSTEM MOVING THROUGH THE REGION BRINGING SHOWERS AND THUNDERSTORMS TO THE AREA AFTER MIDNIGHT. PREV FORECAST WAS MUCH FURTHER NORTH WITH THE SHOWERS AND THUNDERSTORMS, HOWEVER THE MORE RECENT HRRR AND NAM ARE BOTH IMPACTING THE MAJORITY OF THE TERMINALS THROUGH MIDDAY TOMORROW. HAVE TRIED TO TIME BEST CHANCES WITH VC, KEEPING THE TS IN THE SHORTER RANGE, ESP WITH THE LACK OF SIGNIF THUNDER IN MUCH OF THE PRECIP ACTIVITY SW OF THE OFFICE. CONCERN FOR VIS REDUCTION MAY WORK INTO THE NEXT FORECAST IN BMI/CMI REGION IF THE PRECIP IS A BIT SLOWER TO THE AREA. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GEELHART LONG TERM...SMITH AVIATION...HJS
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1236 PM CDT THU JUL 9 2015 .UPDATE... ISSUED AT 1010 AM CDT THU JUL 9 2015 NORTHERN EDGE OF THE CLOUD SHIELD STARTING TO ERODE A BIT... WITH MORE SUBSTANTIAL CLEARING ACROSS NORTHERN MISSOURI. STILL SEEING SOME PATCHY DRIZZLE FROM ABOUT PEORIA-LINCOLN EASTWARD IN THE LOWER CLOUDS...BUT THE HEIGHT OF THE STRATUS IS SLOWLY LIFTING AND THIS SHOULD ONLY BE A CONCERN FOR ANOTHER HOUR OR TWO. HRRR TRYING TO SHOW THE CLOUDS CONTRACTING FROM ALL SIDES...WHICH WOULD POTENTIALLY ALLOW THE HIGHS TO REACH THE MID 70S. HAVE ADJUSTED TEMPERATURES DOWNWARD A BIT AND CONCENTRATED THE LOWER READINGS ALONG THE I-72 CORRIDOR...WITH WARMER HIGHS IN THE NORTHWEST AND SOUTHWEST REACHES OF THE FORECAST AREA. && .SHORT TERM...(TODAY) ISSUED AT 329 AM CDT THU JUL 9 2015 08Z/3AM SURFACE ANALYSIS SHOWS 1010MB LOW JUST NORTH OF KDNV...WITH COLD FRONT EXTENDING SOUTHWESTWARD INTO THE OZARKS. AS THE LOW PULLS FURTHER AWAY...FRONT WILL SETTLE TO NEAR OR JUST SOUTH OF THE OHIO RIVER LATER TODAY. AS A RESULT...AFTER PERHAPS A FEW LINGERING SHOWERS NEAR THE INDIANA BORDER EARLY THIS MORNING...TODAY WILL BE A MOSTLY DRY DAY ACROSS CENTRAL AND SOUTHEAST ILLINOIS. DESPITE THE DRYING TREND...FORECAST SOUNDINGS SHOW PLENTY OF LOW-LEVEL MOISTURE REMAINING...SO PROSPECTS FOR CLEARING ARE BLEAK. DUE TO EXTENSIVE CLOUD COVER...HIGH TEMPERATURES WILL CONTINUE TO BE WELL BELOW NORMAL FOR EARLY JULY...WITH READINGS ONLY REACHING THE LOWER TO MIDDLE 70S. .LONG TERM...(TONIGHT THROUGH WEDNESDAY) ISSUED AT 329 AM CDT THU JUL 9 2015 WITH FRONT GETTING PUSHED A BIT FURTHER SOUTH THAN PREVIOUSLY FORECAST...NOCTURNAL CONVECTION DEVELOPING ALONG THE BOUNDARY ON THE NOSE OF A LOW-LEVEL JET HAS BEEN DISPLACED SOUTHWARD AS WELL TONIGHT. BOTH GFS AND NAM NOW SHOW THUNDERSTORM COMPLEX FORMING OVER CENTRAL MISSOURI AFTER MIDNIGHT...THEN SHIFTING E/SE ACROSS MAINLY THE SOUTHERN HALF OF THE KILX CWA LATE TONIGHT INTO FRIDAY MORNING. HAVE ADJUSTED POPS ACCORDINGLY TO FEATURE ONLY LOW CHANCE FOR SHOWERS ALONG/SOUTHWEST OF A RUSHVILLE...TO SPRINGFIELD...TO MATTOON LINE TOWARD DAWN FRIDAY. AS IT STANDS NOW...IT APPEARS HEAVIEST RAIN WITH THIS SYSTEM WILL REMAIN JUST SOUTH OF CENTRAL ILLINOIS...HOWEVER IF 12Z MODELS SHIFT IT FURTHER NORTHWARD A FLASH FLOOD WATCH MAY BE NEEDED FOR THE SOUTHERN PART OF THE AREA. AFTER MORNING STORM COMPLEX TRACKS INTO THE OHIO RIVER VALLEY...FRONTAL BOUNDARY WILL LIKELY REMAIN SUPPRESSED WELL TO THE SOUTH FOR THE REMAINDER OF THE DAY. DUE TO THE MORE SOUTHERN LOCATION OF THE BAROCLINIC ZONE...HAVE TRIMMED POPS TO JUST SLIGHT CHANCE ALONG THE I-74 CORRIDOR ON FRIDAY. UPPER RIDGE WILL GRADUALLY BUILD INTO THE REGION OVER THE UPCOMING WEEKEND...HOWEVER 00Z JULY 9 GFS/ECMWF ARE BOTH WEAKER WITH THE RIDGE. THIS MEANS THE ONCE DRY FORECAST WILL NOW BE REPLACED BY A MORE UNSETTLED SCENARIO WHERE NOCTURNAL CONVECTION RIDING ALONG THE PERIPHERY OF THE RIDGE MAY IMPACT PARTS OF CENTRAL ILLINOIS. THE MOST SIGNIFICANT MCS LOOKS TO DEVELOP SATURDAY EVENING OVER IOWA...THEN TRACK E/SE ACROSS NORTH-CENTRAL ILLINOIS SATURDAY NIGHT INTO EARLY SUNDAY MORNING. WILL THEREFORE CARRY LIKELY POPS NORTH OF THE PEORIA AREA AT THAT TIME...TAPERING DOWN TO DRY CONDITIONS SOUTH OF I-70. AFTER THAT...RIDGE SHIFTS WESTWARD AND TROUGH DIGS OVER THE GREAT LAKES/MIDWEST...HOWEVER IT MAY NOT BE AS DEEP AS ONCE THOUGHT. END RESULT WILL BE A PERIOD OF VERY WARM/HUMID WEATHER WITH DAILY CHANCES FOR SHOWERS/THUNDER INTO EARLY NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1236 PM CDT THU JUL 9 2015 AREA OF IFR CEILINGS CONTRACTING ACROSS CENTRAL ILLINOIS AND WERE CENTERED ALONG THE KSPI-KCMI CORRIDOR AT 17Z. THESE WILL CONTINUE TO SLOWLY IMPROVE TO MVFR BY EARLY AFTERNOON AND VFR BY AROUND 23Z...ALTHOUGH AM A BIT MORE SKEPTICAL FOR KCMI AND KEPT THEM MVFR INTO THE EVENING. CONDITIONS ALREADY IMPROVING TO VFR AT KPIA AND SHOULD FOLLOW SOON AT KBMI. CONCERNS OVERNIGHT FOR POTENTIAL FOR FOG DEVELOPMENT AS WELL AS INCOMING CONVECTION. AM MOST WORRIED ABOUT KBMI...WHICH HAD OVER 4 INCHES OF RAIN IN THE LAST 24 HOURS AND SHOULD HAVE SOME LIGHT WINDS AND PARTLY CLOUDY SKIES TO GO ALONG WITH THE EXCESSIVELY WET SOIL. WENT WITH 1SM VISIBILITY LATE NIGHT THERE...BUT WITH AROUND 4SM ELSEWHERE. HOWEVER...THE REMAINING TAF SITES ARE ALL CLOSE TO HEAVY RAIN TRACKS AND WILL NEED TO BE MONITORED CLOSELY. AS FOR THE CONVECTION...MOST OF THE MODELS ARE SUGGESTING THE POST-12Z TIME FRAME AS BEING MOST LIKELY FOR SHOWERS. DID NOT MENTION ANY THUNDER FOR NOW. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEELHART SHORT TERM...BARNES LONG TERM...BARNES AVIATION...GEELHART
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1010 AM CDT THU JUL 9 2015 .UPDATE... ISSUED AT 1010 AM CDT THU JUL 9 2015 NORTHERN EDGE OF THE CLOUD SHIELD STARTING TO ERODE A BIT... WITH MORE SUBSTANTIAL CLEARING ACROSS NORTHERN MISSOURI. STILL SEEING SOME PATCHY DRIZZLE FROM ABOUT PEORIA-LINCOLN EASTWARD IN THE LOWER CLOUDS...BUT THE HEIGHT OF THE STRATUS IS SLOWLY LIFTING AND THIS SHOULD ONLY BE A CONCERN FOR ANOTHER HOUR OR TWO. HRRR TRYING TO SHOW THE CLOUDS CONTRACTING FROM ALL SIDES...WHICH WOULD POTENTIALLY ALLOW THE HIGHS TO REACH THE MID 70S. HAVE ADJUSTED TEMPERATURES DOWNWARD A BIT AND CONCENTRATED THE LOWER READINGS ALONG THE I-72 CORRIDOR...WITH WARMER HIGHS IN THE NORTHWEST AND SOUTHWEST REACHES OF THE FORECAST AREA. && .SHORT TERM...(TODAY) ISSUED AT 329 AM CDT THU JUL 9 2015 08Z/3AM SURFACE ANALYSIS SHOWS 1010MB LOW JUST NORTH OF KDNV...WITH COLD FRONT EXTENDING SOUTHWESTWARD INTO THE OZARKS. AS THE LOW PULLS FURTHER AWAY...FRONT WILL SETTLE TO NEAR OR JUST SOUTH OF THE OHIO RIVER LATER TODAY. AS A RESULT...AFTER PERHAPS A FEW LINGERING SHOWERS NEAR THE INDIANA BORDER EARLY THIS MORNING...TODAY WILL BE A MOSTLY DRY DAY ACROSS CENTRAL AND SOUTHEAST ILLINOIS. DESPITE THE DRYING TREND...FORECAST SOUNDINGS SHOW PLENTY OF LOW-LEVEL MOISTURE REMAINING...SO PROSPECTS FOR CLEARING ARE BLEAK. DUE TO EXTENSIVE CLOUD COVER...HIGH TEMPERATURES WILL CONTINUE TO BE WELL BELOW NORMAL FOR EARLY JULY...WITH READINGS ONLY REACHING THE LOWER TO MIDDLE 70S. .LONG TERM...(TONIGHT THROUGH WEDNESDAY) ISSUED AT 329 AM CDT THU JUL 9 2015 WITH FRONT GETTING PUSHED A BIT FURTHER SOUTH THAN PREVIOUSLY FORECAST...NOCTURNAL CONVECTION DEVELOPING ALONG THE BOUNDARY ON THE NOSE OF A LOW-LEVEL JET HAS BEEN DISPLACED SOUTHWARD AS WELL TONIGHT. BOTH GFS AND NAM NOW SHOW THUNDERSTORM COMPLEX FORMING OVER CENTRAL MISSOURI AFTER MIDNIGHT...THEN SHIFTING E/SE ACROSS MAINLY THE SOUTHERN HALF OF THE KILX CWA LATE TONIGHT INTO FRIDAY MORNING. HAVE ADJUSTED POPS ACCORDINGLY TO FEATURE ONLY LOW CHANCE FOR SHOWERS ALONG/SOUTHWEST OF A RUSHVILLE...TO SPRINGFIELD...TO MATTOON LINE TOWARD DAWN FRIDAY. AS IT STANDS NOW...IT APPEARS HEAVIEST RAIN WITH THIS SYSTEM WILL REMAIN JUST SOUTH OF CENTRAL ILLINOIS...HOWEVER IF 12Z MODELS SHIFT IT FURTHER NORTHWARD A FLASH FLOOD WATCH MAY BE NEEDED FOR THE SOUTHERN PART OF THE AREA. AFTER MORNING STORM COMPLEX TRACKS INTO THE OHIO RIVER VALLEY...FRONTAL BOUNDARY WILL LIKELY REMAIN SUPPRESSED WELL TO THE SOUTH FOR THE REMAINDER OF THE DAY. DUE TO THE MORE SOUTHERN LOCATION OF THE BAROCLINIC ZONE...HAVE TRIMMED POPS TO JUST SLIGHT CHANCE ALONG THE I-74 CORRIDOR ON FRIDAY. UPPER RIDGE WILL GRADUALLY BUILD INTO THE REGION OVER THE UPCOMING WEEKEND...HOWEVER 00Z JULY 9 GFS/ECMWF ARE BOTH WEAKER WITH THE RIDGE. THIS MEANS THE ONCE DRY FORECAST WILL NOW BE REPLACED BY A MORE UNSETTLED SCENARIO WHERE NOCTURNAL CONVECTION RIDING ALONG THE PERIPHERY OF THE RIDGE MAY IMPACT PARTS OF CENTRAL ILLINOIS. THE MOST SIGNIFICANT MCS LOOKS TO DEVELOP SATURDAY EVENING OVER IOWA...THEN TRACK E/SE ACROSS NORTH-CENTRAL ILLINOIS SATURDAY NIGHT INTO EARLY SUNDAY MORNING. WILL THEREFORE CARRY LIKELY POPS NORTH OF THE PEORIA AREA AT THAT TIME...TAPERING DOWN TO DRY CONDITIONS SOUTH OF I-70. AFTER THAT...RIDGE SHIFTS WESTWARD AND TROUGH DIGS OVER THE GREAT LAKES/MIDWEST...HOWEVER IT MAY NOT BE AS DEEP AS ONCE THOUGHT. END RESULT WILL BE A PERIOD OF VERY WARM/HUMID WEATHER WITH DAILY CHANCES FOR SHOWERS/THUNDER INTO EARLY NEXT WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 649 AM CDT THU JUL 9 2015 PLENTY OF LOW LEVEL MOISTURE THIS MORNING BEHIND THE DEPARTING LOW PRESSURE WILL KEEP LIFR CLOUDS AND MVFR FOG THROUGH AT LEAST MID MORNING. FORECAST SOUNDINGS AND UPSTREAM OBS INDICATE WE SHOULD SEE VIS IMPROVE TO VFR LATE THIS MORNING WITH MVFR CLOUDS LINGERING WELL INTO THE AFTERNOON. WE EXPECT VFR CONDITIONS FOR ALL TERMINAL SITES BY SUNSET, WHICH SHOULD CONTINUE UNTIL LATE TONIGHT WHEN MVFR FOG REDEVELOPS WHERE SKIES CLEAR OUT. WINDS WILL BE NORTHWEST AT 8-12KT TODAY...THEN BECOME LIGHT WEST-SOUTHWEST LATE TONIGHT. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEELHART SHORT TERM...BARNES LONG TERM...BARNES AVIATION...SHIMON
...UPDATE TO AVIATION FORECAST DISCUSSION...

.SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 312 PM CDT FRI JUL 10 2015 THERE APPEARS TO BE A WEAK SHORTWAVE LIFTING NORTHEAST THROUGH SOUTHERN KS PER THE 19Z WATER VAPOR IMAGERY AND PROFILER DATA. THIS WAVE IS RATHER SUBTLE HOWEVER. A CUTOFF UPPER LOW APPEARS TO BE SPINNING OVER NV WHILE THE MEAN WESTERLIES REMAIN WELL NORTH ACROSS CANADA. AT THE SURFACE, A WARM FRONT WAS NOTED JUST NORTH OF WICHITA AND FORT SCOTT KANSAS. STRONGER DESTABILIZATION SOUTH OF THE BOUNDARY HAS ALLOWED FOR STORMS TO GROW UPSCALE. THINK SCATTERED STORMS ARE LIKELY TO LINGER AS LONG AS THE WEAK SHORTWAVE REMAINS ALOFT SINCE THERE IS NOT MUCH INHIBITION. ANY SURFACE BASED STORMS TAPPING INTO THE STRONGER INSTABILITY ALONG AND SOUTH OF THE WARM FRONT WILL HAVE THE POTENTIAL FOR HAIL AND DAMAGING WINDS. THERE MAY ALSO BE A SMALL CHANCE FOR A TORNADO IF STORMS ARE ABLE TO RIDE ALONG THE BOUNDARY. CONFIDENCE IN WHEN STORMS WILL FALL APART IS RATHER LOW AS MODELS CONTINUE TO GENERATE SOME QPF THROUGH THE NIGHT. HOWEVER ONE WOULD EXPECT THE WAVE TO EVENTUALLY LIFT NORTH AND EAST OR SHEAR OUT AS THE BOUNDARY LAYER BEGINS TO STABILIZE. BECAUSE OF THIS HAVE POPS GRADUALLY TRENDING DOWN OVERNIGHT. MOSTLY CLOUDY SKIES AND CONTINUES LOW LEVEL WARM AIR ADVECTION IS EXPECTED TO KEEP TEMPS RATHER MILD OVERNIGHT. LOWS SATURDAY MORNING ARE EXPECTED TO BE AROUND 70 TO THE MID 70S. FOR SATURDAY, MODELS ARE SKETCHY ON WHETHER THERE MAY BE ANOTHER VORT MAX OVERHEAD. THE NAM HAS SIGNS THAT THERE COULD BE SOME WEAK VORTICITY, WHILE THE GFS ADVECTS AN ELEVATED MIXED LAYER INTO THE FORECAST AREA WITH NO SIGNS OF FORCING. IN GENERAL MODELS SEEM TO BE LESS BULLISH WITH THEIR QPF PROGS AND WITH HEIGHTS RISING THROUGH THE DAY THINK THE GFS MAY BE ONTO SOMETHING. WITH THIS IN MIND, HAVE A DRY FORECAST THROUGH THE DAY. HAVE HIGHS FROM THE LOWER 90S OVER EAST CENTRAL KS TO THE UPPER 90S OVER NORTH CENTRAL KS BASED ON THE BOUNDARY LAYER MIXED DEPTH. MIXING IS EXPECTED TO BE A LITTLE DEEPER ACROSS WESTERN COUNTIES THAN IT SHOULD BE IN EASTERN KS. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 312 PM CDT FRI JUL 10 2015 ON SATURDAY NIGHT THE LOW LEVEL JET INCREASES OUT OF THE SOUTHWEST OVER THE AREA WITH MOST OF THE CONVERGENCE FURTHER EAST OVER IA AND MO. ELEVATED CONVECTION IS LIKELY ALONG THE NOSE OF THE LOW LEVEL JET AS IT VEERS TO A MORE WESTERLY DIRECTION. TOWARDS SUNRISE AND SHORTLY AFTER THE JET WILL BEGIN TO WEAKEN AND THE AREA OF CONVERGENCE COULD MOVE CLOSER TO THE KS/MO STATE. ALSO THE JET COULD INTERACT WITH ANY POSSIBLE GRAVITY WAVE PROGAGATING FROM THE ELEVATED CONVECTION TO THE EAST. MOST OF THE MODELS ARE SHOWING THESE ELEVATED SHOWERS AND POSSIBLY ISOLATED THUNDER WITH THE EXCEPTION OF THE NAM WHICH IS FURTHER NORTHEAST WITH THIS ACTIVITY. THIS ACTIVITY COULD LINGER INTO THE LATE MORNING HOURS. HAVE LEFT THE FORECAST DRY FOR NOW SINCE THE BETTER LIFT COULD BE FOCUSED JUST TO THE EAST OF THE FORECAST AREA AND COVERAGE IS NOT EXPECTED TO BE MUCH. THE REST OF SUNDAY WILL BE DRY WITH TEMPERATURES RISING INTO THE MID 90S TO LOWER 100S, AND DEW POINTS REACHING THE UPPER 60S TO LOWER 70S. WARMEST TEMPERATURES WILL BE ACROSS CENTRAL KS AND HIGHEST DEW POINTS WILL BE ACROSS EASTERN KS. THIS COMBINATION WILL CAUSE HEAT INDICES TO BE NEAR 105 MAKING CONDITIONS RATHER UNCOMFORTABLE. DURING THE DAY MONDAY A SHORTWAVE DIGGING OVER THE GREAT LAKES REGION WILL DRAG A FRONT INTO PORTIONS OF CENTRAL AND EASTERN KS. LOW LEVEL CONVERGENCE ALONG THE FRONT APPEARS TO BE RATHER WEAK AND THE UPPER LEVEL SUPPORT IS SOMEWHAT REMOVED TO THE NORTHEAST. GFS SOUNDINGS DO SHOW SURFACE HEATING WILL REMOVE THE CAP IN PLACE AND ANY ORGANIZED LIFT COULD SET OFF A HIGH BASE STORM DURING THE LATE AFTERNOON AND EVENING HOURS AS THE FRONT SLOWS ITS SOUTHWARD PROGRESS. WITH LOW CONFIDENCE AT THIS POINT HAVE LEFT THE FORECAST DRY. REGARDLESS OF THE PRECIP CHANCES DEW POINTS AND TEMPERATURES WILL CAUSE HEAT INDICES TO RANGE FROM 100-107 MONDAY AFTERNOON AND EARLY EVENING. DECIDED TO LOWER DEW POINTS SLIGHTLY FROM THE GUIDANCE THINKING THAT THE MIXING WILL BE STRONGER THAN THE MODELS ARE FORECASTING. SLIGHT TO CHANCE POPS FROM MONDAY NIGHT THROUGH FRIDAY AS AN UPPER LEVEL RIDGE OVER THE SOUTHERN CONUS BEGINS TO BREAK DOWN. A MID LEVEL TROUGH BEGINS TO DEEPEN OVER THE GREAT LAKES, HELPING TO FLATTEN OUT THE RIDGE TUESDAY INTO WEDNESDAY. FLOW OVER NORTHEAST KANSAS WILL BECOME EAST/NORTHEAST WITH EMBEDDED SHORTWAVES MOVING OVER THE AREA THROUGH THE WEEK. BEST CHANCES FOR PRECIPITATION LOOK TO BE WEDNESDAY, WEDNESDAY NIGHT, AND THURSDAY NIGHT AS A STATIONARY FRONT SITS OVER CENTRAL KANSAS HELPING TO AID IN LOW LEVEL FORCING. AS FOR TEMPERATURES, TUESDAY WILL BE HOT WITH TEMPERATURES TO THE MID TO UPPER 90S, AND HEAT INDICIES BETWEEN 98-103 DEGREES. THE REST OF THE WEEK, HIGH TEMPERATURES COOL SLIGHTLY INTO THE LOWER 90S. LOWS STAY IN THE UPPER 60S TO LOW 70S. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 622 PM CDT FRI JUL 10 2015 STORMS CONTINUE THIS EVENING WITH THE MAIN PRECIPITATION STAYING JUST SOUTHEAST OF THE TAF SITES. MODELS INDICATE SITES SHOULD SEE AN END TO PRECIPITATION BY 03Z, ALTHOUGH THE HRRR IS PICKING UP ON A MCS MOVING INTO THE CWA FROM THE WEST BY APPROXIMATELY 02Z. BELIEVE IF THIS HAPPENS, STORMS WILL DISSIPATE BEFORE REACHING THE TAF SITES. FOR THIS REASON, HAVE LEFT ANY FURTHER MENTION OF VCTS OUT AFTER 03Z ALTHOUGH THIS WILL NEED TO MONITORED IF TRENDS CHANGE. WINDS WILL BECOME GUSTY LATE MORNING AND CONTINUE THROUGH THE END OF THE PERIOD. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...WOLTERS LONG TERM...HELLER/SANDERS AVIATION...HELLER
AREA FORECAST DISCUSSION
NWS TOPEKA KS
322 PM CDT THU JUL 9 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 315 PM CDT THU JUL 9 2015 1930Z WATER VAPOR IMAGERY SHOWS A CUT OFF LOW OVER THE SIERRA NEVADAS. A SHORTWAVE WAS NOTED LIFTING THROUGH AZ WHILE A SECOND SHORTWAVE MOVED ACROSS OK. AT THE SURFACE, A WEAK AREA OF HIGH PRESSURE WAS NOTED OVER THE LOWER MO RIVER VALLEY AND A WARM FRONT WAS OBSERVED FROM SOUTHERN OK INTO SOUTHEASTERN MO. THE NAM AND RAP HAVE TRENDED TO KEEPING THE SHORTWAVE FROM THIS MORNING MAINLY SOUTH OF THE FORECAST AREA. THIS HAS KEPT THE PRECIP MAINLY TO THE SOUTH. EVENTUALLY BY THIS EVENING, THINK THE SHORTWAVE WILL HAVE PASSED TO THE EAST TAKING THE FORCING AWAY FROM THE AREA. THEREFORE HAVE TRENDED POPS DOWN FOR THIS EVENING. LOWS SHOULD FALL INTO THE MIDDLE 60S EXPECTING SOME CLOUD COVER TO REMAIN OVER THE AREA THROUGH THE NIGHT. IF WE CLEAR OUT, TEMPS COULD BE A LITTLE COOLER AND THERE MAY BE SOME PATCHY FOG AROUND IN THE LOW LYING AREAS. FOR FRIDAY, MODELS SHOW WARM AIR ADVECTING IN FROM THE SOUTHWEST WITH SHORTWAVE ENERGY FROM AZ MOVING INTO CENTRAL KS. BECAUSE OF THIS HAVE CONTINUED WITH HIGHS IN THE MID AND UPPER 80S AND HAVE TRENDED POPS HIGHER IN THE AFTERNOON. THE GFS AND NAM DEVELOP SOME REASONABLE INSTABILITY, SO THERE MAY BE SOME AFTERNOON CONVECTION POP UP. DEEP LAYER SHEAR REMAINS RATHER WEAK SO AM NOT SURE HOW ORGANIZED IT MAY BE. ALSO MODELS HAVE NOT SHOWN THE BEST SKILL IN HANDLING THESE WEAK WAVES KICKING OUT, SO HAVE KEPT POPS IN THE 40 TO 60 PERCENT RANGE. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 315 PM CDT THU JUL 9 2015 FRIDAY NIGHT THROUGH SUNDAY MAIN FOCUS FOR THE WEEKEND PERIOD IS THE CHANCE FOR SHOWERS AND THUNDERSTORMS FRIDAY EVENING, FOLLOWED QUICKLY BY THE HEAT DURING THE AFTERNOON PERIODS. BY EARLY FRIDAY EVENING, A SHORTWAVE TROUGH IS PROGGED TO LIFT NORTHEAST OUT OF THE CO ROCKIES INTO NEBRASKA, DEEPENING THE SURFACE TROUGH ACROSS WESTERN KANSAS. ALL GUIDANCE IS FAIRLY SIMILAR IN DEVELOPING SHOWERS AND STORMS ALONG THE WEST TO EAST WARM FRONT NEAR THE KS AND NE BORDER. THE INCREASING LLJ THROUGH THE EVENING WILL CONTINUE TO AID DEVELOPMENT THROUGH EARLY SATURDAY MORNING. BEST CHANCES FOR PRECIP WERE CENTERED NORTH OF INTERSTATE 70, HIGHEST NEAR THE NEBRASKA AND MISSOURI BORDERS. SEVERE STORMS ARE NOT EXPECTED GIVEN THE WEAK EFFECTIVE SHEAR NEAR 25 KTS. CLOUDS CLEAR OUT WEST TO EAST ON SATURDAY AS STRONG MIXING THROUGH 850 MB ADVECTS TEMPS TO THE UPPER 20S C INTO NORTH CENTRAL KS. AT THIS TIME, HAVE TRENDED WARMER FOR NORTH CENTRAL KS INTO THE UPPER 90S WITH LOWER 90S FURTHER EAST. HEAT INDICES ARE EXPECTED TO REACH BETWEEN 100 AND 103 DEGREES SATURDAY AFTERNOON. WITH NO CHANGE IN AIRMASS AND OVERNIGHT LOWS IN THE 70S, BELIEVE HIGHS WILL EASILY WARM FROM THE MIDDLE 90S TO LOWER 100S FOR SUNDAY. HEAT INDICES MAY VARY BY A FEW DEGREES BASED ON HOW WELL WE CAN MIX OUT THE LOW 70 DEWPOINTS DURING THE LATE AFTERNOON. THE CURRENT FORECAST OF UPPER 60S TO LOWER 70S WILL TRANSLATE TO MAX HEAT INDICES FROM 103 TO 106 DEGREES. IF TRENDS CONTINUE, HEAT HEADLINES MAY BE NEEDED, ESPECIALLY FOR SUNDAY. SUNDAY NIGHT THROUGH THURSDAY MID-LEVEL RIDGING DOMINATES THE SOUTHERN CONUS SUNDAY NIGHT WITH THE HIGH CENTERED OVER THE TEXAS/OKLAHOMA BOARDER. AT THE SURFACE, A LOW PRESSURE AREA WILL REMAIN IN WESTERN KANSAS FOR MOST OF THE DAY MONDAY ALLOWING SOUTHWEST FLOW AT THE SURFACE. MONDAY IS LOOKING TO BE THE HOTTEST DAY OF THE PERIOD WITH HIGHS RANGING FROM MID 90S UP TO 101 DEGREES. HEAT INDICES THROUGHOUT THE CWA ARE EXPECTED TO BE ABOVE 100 DEGREES, POSSIBLY UP TO 105 IN SOME AREAS. A COLD FRONT MOVES THROUGH THE AREA LATE MONDAY BRINGING SMALL CHANCES FOR PRECIPITATION THAT EVENING AND OVERNIGHT. TUESDAY LOOKS TO BE DRY WITH THE NEXT CHANCE FOR STORMS WEDNESDAY INTO THURSDAY. TEMPERATURES WILL SLIGHTLY COOL FROM TUESDAY THROUGH THURSDAY, WITH HIGHS FORECAST IN THE MID TO UPPER 80S THURSDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1221 PM CDT THU JUL 9 2015 SHOWERS HAVE HAD A HARD TIME LIFTING NORTH THIS MORNING WITH THE INITIAL SHORTWAVE MOVING ALONG THE OK STATE LINE PER THE 17Z WATER VAPOR IMAGERY. WITH RECENT HI RES GUIDANCE KEEPING THE BETTER PVA TO THE SOUTH ACROSS NORTHEAST OK/SOUTHEAST KS, THINK CHANCES THE SHOWER ACTIVITY MOVES INTO THE TERMINALS IS DECREASING AND WILL KEEP THE FORECAST DRY. NAM AND GFS PROGS SHOW SOME CIG AND VSBY RESTRICTIONS DEVELOPING OVERNIGHT WITH HIGH RH IN THE BOUNDARY LAYER. CONFIDENCE IS NOT THAT GREAT SINCE THE RAP WANTS TO MAINTAIN VFR CONDITIONS. GIVEN THE AMOUNT OF MOISTURE IN THE BOUNDARY LAYER AND EXPECTED LIGHT WINDS OVERNIGHT, SOME MVFR CIGS AND VSBY SEEM PLAUSIBLE, ALTHOUGH I AM SOMEWHAT SKEPTICAL OF THE IFR CONDITIONS IN THE MET MOS. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...WOLTERS LONG TERM...BOWEN/HELLER AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1149 AM MDT THU JUL 9 2015 .SHORT TERM...(THIS MORNING THROUGH SATURDAY NIGHT) ISSUED AT 253 AM MDT THU JUL 9 2015 EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW LARGE SCALE CLOSED TROUGH OVER CENTRAL CALIFORNIA...RIDGING ACROSS THE SOUTHEAST US...AND DIFFLUENT/SW FLOW ACROSS THE SOUTHERN PLAINS AND CENTRAL ROCKIES. TWO SHORTWAVE TROUGHS ARE IMPACTING PARTS OF THE ROCKIES PLAINS...ONE OVER WYOMING...THE OTHER OVER THE OK/TX PANHANDLES. BOTH OF THESE FEATURES HAVE SPLIT AROUND OUR CWA...WITH WEAKER HEIGHT FALLS IN PLACE ACROSS THE CWA. THIS MORNING...ISOLATED TO SCATTERED LIGHT/MODERATE SHOWERS CONTINUE TO IMPACT SOME LOCATIONS IN NW KANSAS/SW NEBRASKA...HOWEVER BEST FORCING AND INSTABILITY ARE WELL SOUTH. GOOD MOISTURE AND LIMITED ISENTROPIC ASCENT WILL CONTINUE TO SUPPORT ADDITIONAL SHOWER/ISOLATED THUNDERSTORM POTENTIAL...HOWEVER TRENDS ARE MUCH DRIER THAN GUIDANCE 12HR AGO. AREA OBS/SATELLITE SHOW LIGHT FOG/STRATUS...AND WITH GOOD BL MOISTURE IN PLACE I DECIDED TO INCLUDE PATCHY FOG MENTION THROUGH MID MORNING. TODAY-FRIDAY NIGHT...WEAK FORCING CONTINUES TO BE ADVERTISED ACROSS THE CWA ALONG WITH GOOD MOISTURE (PWATS/TD). AS THE DAY GOES ON CAPE VALUES INCREASE...AND SURFACE TROUGH ALONG KS/CO BORDER MAY ACT AS FOCUS FOR ADDITIONAL DEVELOPMENT. MODELS ARE SHOWING AT LEAST WEAK HEIGHT FALLS WITH SERIES OF SHORT WAVE TROUGHS ROTATING FROM THE SW ACROSS THE ROCKIES/PLAINS. VERY LOW CONFIDENCE DUE TO LACK OF MODEL CONTINUITY/CONSISTENCY REGARDING THE TIMING/TRACK OF THESE FEATURES. I KEPT 20-40 POPS IN PLACE BASED ON MODEL PRECIP SIGNALS/CURRENT CONSENSUS TIMING FRIDAY EVENING. BY LATE FRIDAY NIGHT RETROGRADING/STRENGTHENING RIDGE SHOULD RESULT IN ANY THUNDERSTORM ACTIVITY ENDING FROM THE SOUTHWEST TO NORTHEAST. TEMPERATURES ARE PARTICULARLY TRICKY TODAY AS EVEN WITH LESS SHOWER/THUNDERSTORM COVERAGE WE WILL BE IMPACTED BY STRATUS AT LEAST THROUGH MIDDAY WHICH COULD HAVE AN IMPACT ON HIGHS. I COULD STILL SEE SOME LOCATIONS STRUGGLE TO WARM OUT OF THE UPPER 60S/LOWER 70S DEPENDING ON CLEARING SHOWER/THUNDERSTORM COVERAGE. HIGHS FRIDAY ARE EXPECTED TO BE WARMER...WITH THE DECREE OF WAA ADVERTISED BY EVEN CONSERVATIVE GUIDANCE SUPPORTING SEASONAL HIGHS AROUND 90F. IN FACT...MORE AGGRESSIVE GUIDANCE SHOWING RIDGE FURTHER EAST/MORE AMPLIFIED MAY SUPPORT MID-UPPER 90S. SATURDAY-SATURDAY NIGHT...WITH CWA UNDER THE INFLUENCE OF AMPLIFYING RIDGE TEMPERATURES SHOULD BE EVEN WARMER...WITH SOME LOCATIONS APPROACHING 100F. SOME GUIDANCES KEEPS SURFACE TROUGH A LITTLE FARTHER EAST...WHICH MAY RESULT IN TEMPS SLIGHTLY "COOLER"...HOWEVER EVEN IN THIS SCENARIO WE WILL SEE ABOVE NORMAL HIGHS IN THE MID- UPPER ACROSS A LOT OF THE AREA. STRONG CAP MAY LIMIT CONVECTIVE POTENTIAL...AND THERE IS LITTLE IN THE WAY OF LARGE SCALE FORCING DUE TO RIDGE. SEVERAL MODELS ARE SHOWING CAP WEAKENING ALONG SURFACE TROUGH WITH ISOLATED THUNDERSTORM POTENTIAL DURING THE AFTERNOON/EARLY EVENING PERIOD. IM NOT REALLY CONFIDENT ABOUT THIS...BUT DECIDED TO GO AHEAD AND INCLUDE SLIGHT CHANCE MENTION FOR NOW. .LONG TERM...(SUNDAY THROUGH WEDNESDAY) ISSUED AT 253 AM MDT THU JUL 9 2015 HIGH PRESSURE SITUATED OVER THE TEXAS/NEW MEXICO BORDER WILL SLOWLY DRIFT WEST AND ELONGATE SUNDAY THROUGH THURSDAY. PRECIPITATION CHANCES ARE NOT IN THE FORECAST FOR SUNDAY WITH VERY LOW CHANCES MAINLY IN THE SOUTHERN PORTIONS OF THE CWA AS WE HEAD INTO MONDAY. A SHORTWAVE WILL TRAVERSE THE REGION ON TUESDAY AND INTO WEDNESDAY... RAISING POPS INTO THE 20 TO 30 PERCENT RANGE. CAPE AND 0 TO 6KM SHEAR WILL BE MODEST DURING THIS PERIOD WITH RELATIVELY HIGH DCAPE VALUES. ANY STORMS THAT FORM WILL BE A RISK FOR BRIEF GUSTY WINDS ON TUESDAY AND WEDNESDAY AFTERNOON. ANOTHER RELATIVELY WEAK SHORTWAVE WILL MOVE OUT OF THE CENTRAL ROCKIES ON THURSDAY AND RAISE POPS ONCE MORE ACROSS THE CWA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1143 AM MDT THU JUL 9 2015 VFR CONDITIONS ARE EXPECTED AT KGLD AND KMCK THIS AFTERNOON AS THE CLOUD DECK CONTINUES TO SLOWLY BREAK UP. LATER THIS EVENING THUNDERSTORMS WILL BE POSSIBLE AT BOTH SITES WITH SOME POSSIBLE MVFR NEAR STORMS. STRATUS AND FOG SHOULD RESULT IN SOME BRIEF MVFR CONDTIONS AT KMCK AND KGLD FRIDAY MORNING. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...TL AVIATION...FS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1221 PM CDT THU JUL 9 2015 ...AVIATION UPDATE... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 414 AM CDT THU JUL 9 2015 JUST A FEW SHOWERS OUT WEST AT THIS HOUR...WHILE TEMPERATURES ACROSS THE AREA HAVE FALLEN INTO THE LOWER 60S EVEN WITH PERIODS OF CLOUD COVER. WARM FRONT HAS SETTLED TO OUR SOUTH IN OKLAHOMA...WITH SHOWERS AND THUNDERSTORMS ALONG THE BOUNDARY. MAY SEE SOME HAZE OR FOG IN LOW SPOTS OR ALONG BODIES OF WATER BY MORNING BUT NOT EXPECTING WIDESPREAD COVER. FOR TODAY...SERIES OF SHORTWAVES PROGGED TO LIFT FRONTAL BOUNDARY BACK NORTHWARD INTO THE AREA THIS AFTERNOON INTO THE OVERNIGHT HOURS. NOT MUCH INSTABILITY TO WORK WITH UNTIL THE EVENING HOURS...SO MORE LIKELY TO SEE SHOWERS WITH ISOLATED THUNDER WITH CONVECTION. SOUTHWESTERN COUNTIES MAY SEE SHOWERS BY THE NOON HOUR BUT THINK POINTS NORTHEAST WILL NOT SEE MUCH UNTIL THIS EVENING AND HAVE SPREAD POPS SW TO NE ACCORDINGLY. BEST CHANCE FOR RAIN STILL LOOKS TO BE AFTER MIDNIGHT INTO EARLY FRIDAY MORNING AS WHAT APPEARS TO BE A SECONDARY WAVE INCREASES THE 850 FLOW AND ISENTROPIC LIFT ACROSS PRIMARILY THE EASTERN COUNTIES. FOR TEMPERATURES...AS FRONT LIFTS BACK TO THE NORTH MAY SEE SOME SITES REACH THE 80 MARK TODAY BEFORE FALLING BACK INTO THE MIDDLE 60S OVERNIGHT IN CLOUDS AND PERIODS OF RAIN. AREAS ALONG AND SOUTHEAST OF THE KANSAS TURNPIKE COULD PICK UP ANOTHER INCH OF RAINFALL BY FRIDAY MORNING...WITH LESSER AMOUNTS ANTICIPATED NORTHWEST. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 414 AM CDT THU JUL 9 2015 BY FRIDAY MORNING, A BROAD MID-LEVEL RIDGE WILL BE STRETCHED ACROSS THE SOUTHEASTERN U.S. WITH THE RIDGE AXIS BEING NEGATIVELY TILTED INTO THE CENTRAL PLAINS. MODELS CONTINUE TO SHOW A FEW WEAK EMBEDDED WAVES DEVELOPING OVER THE AREA ALONG THE NORTHERN EDGE OF THE RIDGE AXIS, WITH ONE SLIGHTLY MORE PRONOUNCED WAVE EXPECTED TO DEVELOP OVER WESTERN KS AND TRACK OVER THE CWA FRIDAY AFTERNOON INTO FRIDAY EVENING BEFORE LIFTING TO THE NORTHEAST. IF ANYTHING, MODELS ARE IN BETTER AGREEMENT WITH THE TRACKING OF THIS WAVE BEING MORE OVER THE CWA RATHER THAN HOVERING NEAR THE KS/NE BORDER AS SOME PREVIOUS RUNS WERE SUGGESTING. AT THE SURFACE, AN AREA OF LOW PRESSURE WILL BE SITUATED ACROSS THE EASTERN ROCKIES AND HIGH PLAINS WITH AN ASSOCIATED WARM FRONT EXPECTED TO LIFT NORTHWARD INTO THE AREA. MODELS HAVE COME INTO SLIGHTLY BETTER AGREEMENT WITH REGARDS TO THE TIMING AND TRACKING OF THIS BOUNDARY, AND THE MODEL TREND HAS BEEN A SLOWER NORTHWARD PROGRESSION OF THIS BOUNDARY. THE GFS CONTINUES TO BE THE FASTEST SOLUTION, BUT IN GENERAL THE WARM FRONT LOOKS TO LIFT INTO THE CWA ON FRIDAY AND PROGRESS NORTH OF THE AREA FRIDAY NIGHT. THE COMBINATION OF THE PASSING SHORTWAVE AND THE LIFTING WARM FRONT SHOULD PROVIDE ENOUGH FORCING AND LIFT TO DEVELOP SCATTERED SHOWERS AND THUNDERSTORMS FRIDAY AND FRIDAY NIGHT. ECMWF IS MOST AGGRESSIVE WITH KEEPING PRECIPITATION LINGERING ACROSS NORTHEAST KS INTO SATURDAY WHILE MOST OTHER MODELS HAVE THE PRECIPITATION EXITING THE AREA. DO NOT EXPECT ANY SEVERE STORMS WITH THIS ACTIVITY AS 0-6KM BULK SHEAR VALUES ARE ONLY UPWARDS OF 20-25KTS AND LAPSE RATES CONTINUE TO LOOK MORE MOIST ADIABATIC. OVER THE WEEKEND, THE MID-LEVEL RIDGE WILL BUILD INTO THE CENTRAL U.S., BROADLY STRETCHING ACROSS THE SOUTHERN TWO-THIRDS OF THE CONUS. MODELS CONTINUE TO SHOW THE POTENTIAL FOR SOME WEAK EMBEDDED WAVES TO DEVELOP ALONG THE NORTHERN RIDGE AXIS, CLIPPING PORTIONS OF THE FORECAST AREA WITH SOME ISOLATED PRECIPITATION. HOWEVER, MODELS ARE INCONSISTENT AMONGST THEMSELVES AND FROM RUN-TO-RUN WITH THE TIMING AND TRACKING OF THESE WAVES, SO CONFIDENCE IS VERY LOW WITH WHEN AND WHERE THESE ISOLATED PRECIPITATION CHANCES WILL OCCUR. AT THIS TIME, HAVE A DRY FORECAST SATURDAY NIGHT THROUGH MONDAY DUE TO THE LOW CONFIDENCE IN ANY ISOLATED PRECIPITATION DEVELOPMENT. DURING THIS TIME, SURFACE LOW PRESSURE WILL REMAIN WEST OF THE AREA, KEEPING PREVAILING SOUTHWESTERLY FLOW AND STEADY WARM-AIR ADVECTION INTO THE CWA. SUNDAY AND MONDAY ARE LOOKING TO BE THE WARMEST DAYS OF THE UPCOMING WEEK WITH HIGHS REACHING INTO THE MID/UPPER 90S AND HEAT INDICES SOARING INTO THE 100-105 DEGREE RANGE. THE SURFACE LOW PRESSURE FINALLY PROGRESSES EASTWARD INTO THE AREA MONDAY NIGHT INTO TUESDAY, PUSHING A WEAK COLD FRONT INTO THE CWA WHICH MAY HELP TO SUPPORT SOME ISOLATED PRECIPITATION MONDAY NIGHT. TUESDAY INTO WEDNESDAY A MID-LEVEL TROUGH DEVELOPS ACROSS THE EASTERN U.S., RESULTING IN MORE OF A NORTHWESTERLY FLOW ALOFT DEVELOPING OVER THE CWA. A FEW MORE EMBEDDED WAVES MAY TRACK OVER THE AREA WEDNESDAY INTO THURSDAY, WHICH SHOULD BRING MORE SCATTERED PRECIPITATION TO THE AREA. THIS SHIFT IN THE MID-LEVEL PATTERN WILL RESULT IN SLIGHTLY COOLER TEMPERATURES INTO MID-WEEK WITH HIGHS IN THE UPPER 80S TO MID 90S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1221 PM CDT THU JUL 9 2015 SHOWERS HAVE HAD A HARD TIME LIFTING NORTH THIS MORNING WITH THE INITIAL SHORTWAVE MOVING ALONG THE OK STATE LINE PER THE 17Z WATER VAPOR IMAGERY. WITH RECENT HI RES GUIDANCE KEEPING THE BETTER PVA TO THE SOUTH ACROSS NORTHEAST OK/SOUTHEAST KS, THINK CHANCES THE SHOWER ACTIVITY MOVES INTO THE TERMINALS IS DECREASING AND WILL KEEP THE FORECAST DRY. NAM AND GFS PROGS SHOW SOME CIG AND VSBY RESTRICTIONS DEVELOPING OVERNIGHT WITH HIGH RH IN THE BOUNDARY LAYER. CONFIDENCE IS NOT THAT GREAT SINCE THE RAP WANTS TO MAINTAIN VFR CONDITIONS. GIVEN THE AMOUNT OF MOISTURE IN THE BOUNDARY LAYER AND EXPECTED LIGHT WINDS OVERNIGHT, SOME MVFR CIGS AND VSBY SEEM PLAUSIBLE, ALTHOUGH I AM SOMEWHAT SKEPTICAL OF THE IFR CONDITIONS IN THE MET MOS. && .TOP WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...67 LONG TERM...HENNECKE AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
529 AM MDT THU JUL 9 2015 .SHORT TERM...(THIS MORNING THROUGH SATURDAY NIGHT) ISSUED AT 253 AM MDT THU JUL 9 2015 EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW LARGE SCALE CLOSED TROUGH OVER CENTRAL CALIFORNIA...RIDGING ACROSS THE SOUTHEAST US...AND DIFFLUENT/SW FLOW ACROSS THE SOUTHERN PLAINS AND CENTRAL ROCKIES. TWO SHORTWAVE TROUGHS ARE IMPACTING PARTS OF THE ROCKIES PLAINS...ONE OVER WYOMING...THE OTHER OVER THE OK/TX PANHANDLES. BOTH OF THESE FEATURES HAVE SPLIT AROUND OUR CWA...WITH WEAKER HEIGHT FALLS IN PLACE ACROSS THE CWA. THIS MORNING...ISOLATED TO SCATTERED LIGHT/MODERATE SHOWERS CONTINUE TO IMPACT SOME LOCATIONS IN NW KANSAS/SW NEBRASKA...HOWEVER BEST FORCING AND INSTABILITY ARE WELL SOUTH. GOOD MOISTURE AND LIMITED ISENTROPIC ASCENT WILL CONTINUE TO SUPPORT ADDITIONAL SHOWER/ISOLATED THUNDERSTORM POTENTIAL...HOWEVER TRENDS ARE MUCH DRIER THAN GUIDANCE 12HR AGO. AREA OBS/SATELLITE SHOW LIGHT FOG/STRATUS...AND WITH GOOD BL MOISTURE IN PLACE I DECIDED TO INCLUDE PATCHY FOG MENTION THROUGH MID MORNING. TODAY-FRIDAY NIGHT...WEAK FORCING CONTINUES TO BE ADVERTISED ACROSS THE CWA ALONG WITH GOOD MOISTURE (PWATS/TD). AS THE DAY GOES ON CAPE VALUES INCREASE...AND SURFACE TROUGH ALONG KS/CO BORDER MAY ACT AS FOCUS FOR ADDITIONAL DEVELOPMENT. MODELS ARE SHOWING AT LEAST WEAK HEIGHT FALLS WITH SERIES OF SHORT WAVE TROUGHS ROTATING FROM THE SW ACROSS THE ROCKIES/PLAINS. VERY LOW CONFIDENCE DUE TO LACK OF MODEL CONTINUITY/CONSISTENCY REGARDING THE TIMING/TRACK OF THESE FEATURES. I KEPT 20-40 POPS IN PLACE BASED ON MODEL PRECIP SIGNALS/CURRENT CONSENSUS TIMING FRIDAY EVENING. BY LATE FRIDAY NIGHT RETROGRADING/STRENGTHENING RIDGE SHOULD RESULT IN ANY THUNDERSTORM ACTIVITY ENDING FROM THE SOUTHWEST TO NORTHEAST. TEMPERATURES ARE PARTICULARLY TRICKY TODAY AS EVEN WITH LESS SHOWER/THUNDERSTORM COVERAGE WE WILL BE IMPACTED BY STRATUS AT LEAST THROUGH MIDDAY WHICH COULD HAVE AN IMPACT ON HIGHS. I COULD STILL SEE SOME LOCATIONS STRUGGLE TO WARM OUT OF THE UPPER 60S/LOWER 70S DEPENDING ON CLEARING SHOWER/THUNDERSTORM COVERAGE. HIGHS FRIDAY ARE EXPECTED TO BE WARMER...WITH THE DECREE OF WAA ADVERTISED BY EVEN CONSERVATIVE GUIDANCE SUPPORTING SEASONAL HIGHS AROUND 90F. IN FACT...MORE AGGRESSIVE GUIDANCE SHOWING RIDGE FURTHER EAST/MORE AMPLIFIED MAY SUPPORT MID-UPPER 90S. SATURDAY-SATURDAY NIGHT...WITH CWA UNDER THE INFLUENCE OF AMPLIFYING RIDGE TEMPERATURES SHOULD BE EVEN WARMER...WITH SOME LOCATIONS APPROACHING 100F. SOME GUIDANCES KEEPS SURFACE TROUGH A LITTLE FARTHER EAST...WHICH MAY RESULT IN TEMPS SLIGHTLY "COOLER"...HOWEVER EVEN IN THIS SCENARIO WE WILL SEE ABOVE NORMAL HIGHS IN THE MID- UPPER ACROSS A LOT OF THE AREA. STRONG CAP MAY LIMIT CONVECTIVE POTENTIAL...AND THERE IS LITTLE IN THE WAY OF LARGE SCALE FORCING DUE TO RIDGE. SEVERAL MODELS ARE SHOWING CAP WEAKENING ALONG SURFACE TROUGH WITH ISOLATED THUNDERSTORM POTENTIAL DURING THE AFTERNOON/EARLY EVENING PERIOD. IM NOT REALLY CONFIDENT ABOUT THIS...BUT DECIDED TO GO AHEAD AND INCLUDE SLIGHT CHANCE MENTION FOR NOW. .LONG TERM...(SUNDAY THROUGH WEDNESDAY) ISSUED AT 253 AM MDT THU JUL 9 2015 HIGH PRESSURE SITUATED OVER THE TEXAS/NEW MEXICO BORDER WILL SLOWLY DRIFT WEST AND ELONGATE SUNDAY THROUGH THURSDAY. PRECIPITATION CHANCES ARE NOT IN THE FORECAST FOR SUNDAY WITH VERY LOW CHANCES MAINLY IN THE SOUTHERN PORTIONS OF THE CWA AS WE HEAD INTO MONDAY. A SHORTWAVE WILL TRAVERSE THE REGION ON TUESDAY AND INTO WEDNESDAY... RAISING POPS INTO THE 20 TO 30 PERCENT RANGE. CAPE AND 0 TO 6KM SHEAR WILL BE MODEST DURING THIS PERIOD WITH RELATIVELY HIGH DCAPE VALUES. ANY STORMS THAT FORM WILL BE A RISK FOR BRIEF GUSTY WINDS ON TUESDAY AND WEDNESDAY AFTERNOON. ANOTHER RELATIVELY WEAK SHORTWAVE WILL MOVE OUT OF THE CENTRAL ROCKIES ON THURSDAY AND RAISE POPS ONCE MORE ACROSS THE CWA. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 529 AM MDT THU JUL 9 2015 SHOWERS/THUNDERSTORMS WILL BE POSSIBLE THROUGH MOST OF THE TAF PERIOD AT BOTH TERMINALS. HOWEVER...BESIDES ONGOING ACTIVITY NEAR KGLD EARLY IN THE TAF PERIOD...CONFIDENCE IS LOW ON TIMING/COVERAGE. I DECIDED TO ONLY INCLUDE MENTION AT KGLD FOR NOW. STRATUS AND FOG AND DEVELOPED ACROSS EASTERN COLORADO AND AROUND BOTH TERMINALS. MVFR CONDITIONS SHOULD IMPROVE TO VFR BY MID MORNING...HOWEVER BASED ON SURROUNDING OBS THERE IS THE POSSIBILITY FOR BRIEF IFR CONDITIONS. I WASNT CONFIDENT ENOUGH TO ADD DUE TO IMPACTS FROM SHOWERS/THUNDERSTORMS NEAR KMCK...AND BETTER CONDITIONS IN AREAS SURROUND KMCK. WITH ABUNDANT LOW LEVEL MOISTURE STRATUS/FOG WILL BE POSSIBLE AGAIN LATE TONIGHT/EARLY FRIDAY MORNING. AT THIS POINT BEST CHANCES FOR FOG/STRATUS (IFR CONDITIONS OR LOWER) WILL BE AT KMCK BASED ON CURRENT GUIDANCE AS ADVERTISED POSITION OF SURFACE LOW PRESSURE. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...TL AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
253 AM MDT THU JUL 9 2015 .SHORT TERM...(THIS MORNING THROUGH SATURDAY NIGHT) ISSUED AT 253 AM MDT THU JUL 9 2015 EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW LARGE SCALE CLOSED TROUGH OVER CENTRAL CALIFORNIA...RIDGING ACROSS THE SOUTHEAST US...AND DIFFLUENT/SW FLOW ACROSS THE SOUTHERN PLAINS AND CENTRAL ROCKIES. TWO SHORTWAVE TROUGHS ARE IMPACTING PARTS OF THE ROCKIES PLAINS...ONE OVER WYOMING...THE OTHER OVER THE OK/TX PANHANDLES. BOTH OF THESE FEATURES HAVE SPLIT AROUND OUR CWA...WITH WEAKER HEIGHT FALLS IN PLACE ACROSS THE CWA. THIS MORNING...ISOLATED TO SCATTERED LIGHT/MODERATE SHOWERS CONTINUE TO IMPACT SOME LOCATIONS IN NW KANSAS/SW NEBRASKA...HOWEVER BEST FORCING AND INSTABILITY ARE WELL SOUTH. GOOD MOISTURE AND LIMITED ISENTROPIC ASCENT WILL CONTINUE TO SUPPORT ADDITIONAL SHOWER/ISOLATED THUNDERSTORM POTENTIAL...HOWEVER TRENDS ARE MUCH DRIER THAN GUIDANCE 12HR AGO. AREA OBS/SATELLITE SHOW LIGHT FOG/STRATUS...AND WITH GOOD BL MOISTURE IN PLACE I DECIDED TO INCLUDE PATCHY FOG MENTION THROUGH MID MORNING. TODAY-FRIDAY NIGHT...WEAK FORCING CONTINUES TO BE ADVERTISED ACROSS THE CWA ALONG WITH GOOD MOISTURE (PWATS/TD). AS THE DAY GOES ON CAPE VALUES INCREASE...AND SURFACE TROUGH ALONG KS/CO BORDER MAY ACT AS FOCUS FOR ADDITIONAL DEVELOPMENT. MODELS ARE SHOWING AT LEAST WEAK HEIGHT FALLS WITH SERIES OF SHORT WAVE TROUGHS ROTATING FROM THE SW ACROSS THE ROCKIES/PLAINS. VERY LOW CONFIDENCE DUE TO LACK OF MODEL CONTINUITY/CONSISTENCY REGARDING THE TIMING/TRACK OF THESE FEATURES. I KEPT 20-40 POPS IN PLACE BASED ON MODEL PRECIP SIGNALS/CURRENT CONSENSUS TIMING FRIDAY EVENING. BY LATE FRIDAY NIGHT RETROGRADING/STRENGTHENING RIDGE SHOULD RESULT IN ANY THUNDERSTORM ACTIVITY ENDING FROM THE SOUTHWEST TO NORTHEAST. TEMPERATURES ARE PARTICULARLY TRICKY TODAY AS EVEN WITH LESS SHOWER/THUNDERSTORM COVERAGE WE WILL BE IMPACTED BY STRATUS AT LEAST THROUGH MIDDAY WHICH COULD HAVE AN IMPACT ON HIGHS. I COULD STILL SEE SOME LOCATIONS STRUGGLE TO WARM OUT OF THE UPPER 60S/LOWER 70S DEPENDING ON CLEARING SHOWER/THUNDERSTORM COVERAGE. HIGHS FRIDAY ARE EXPECTED TO BE WARMER...WITH THE DECREE OF WAA ADVERTISED BY EVEN CONSERVATIVE GUIDANCE SUPPORTING SEASONAL HIGHS AROUND 90F. IN FACT...MORE AGGRESSIVE GUIDANCE SHOWING RIDGE FURTHER EAST/MORE AMPLIFIED MAY SUPPORT MID-UPPER 90S. SATURDAY-SATURDAY NIGHT...WITH CWA UNDER THE INFLUENCE OF AMPLIFYING RIDGE TEMPERATURES SHOULD BE EVEN WARMER...WITH SOME LOCATIONS APPROACHING 100F. SOME GUIDANCES KEEPS SURFACE TROUGH A LITTLE FARTHER EAST...WHICH MAY RESULT IN TEMPS SLIGHTLY "COOLER"...HOWEVER EVEN IN THIS SCENARIO WE WILL SEE ABOVE NORMAL HIGHS IN THE MID- UPPER ACROSS A LOT OF THE AREA. STRONG CAP MAY LIMIT CONVECTIVE POTENTIAL...AND THERE IS LITTLE IN THE WAY OF LARGE SCALE FORCING DUE TO RIDGE. SEVERAL MODELS ARE SHOWING CAP WEAKENING ALONG SURFACE TROUGH WITH ISOLATED THUNDERSTORM POTENTIAL DURING THE AFTERNOON/EARLY EVENING PERIOD. IM NOT REALLY CONFIDENT ABOUT THIS...BUT DECIDED TO GO AHEAD AND INCLUDE SLIGHT CHANCE MENTION FOR NOW. .LONG TERM...(SUNDAY THROUGH WEDNESDAY) ISSUED AT 253 AM MDT THU JUL 9 2015 HIGH PRESSURE SITUATED OVER THE TEXAS/NEW MEXICO BORDER WILL SLOWLY DRIFT WEST AND ELONGATE SUNDAY THROUGH THURSDAY. PRECIPITATION CHANCES ARE NOT IN THE FORECAST FOR SUNDAY WITH VERY LOW CHANCES MAINLY IN THE SOUTHERN PORTIONS OF THE CWA AS WE HEAD INTO MONDAY. A SHORTWAVE WILL TRAVERSE THE REGION ON TUESDAY AND INTO WEDNESDAY... RAISING POPS INTO THE 20 TO 30 PERCENT RANGE. CAPE AND 0 TO 6KM SHEAR WILL BE MODEST DURING THIS PERIOD WITH RELATIVELY HIGH DCAPE VALUES. ANY STORMS THAT FORM WILL BE A RISK FOR BRIEF GUSTY WINDS ON TUESDAY AND WEDNESDAY AFTERNOON. ANOTHER RELATIVELY WEAK SHORTWAVE WILL MOVE OUT OF THE CENTRAL ROCKIES ON THURSDAY AND RAISE POPS ONCE MORE ACROSS THE CWA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1128 PM MDT WED JUL 8 2015 THE POSSIBILITY OF PRECIPITATION HAS DECREASED OVERNIGHT AND THROUGH TOMORROW ACROSS THE CENTRAL HIGH PLAINS WITH THUNDERSTORMS BEING MORE NUMEROUS ACROSS THE SOUTHERN PLAINS. VFR CONDITIONS ARE STILL EXPECTED TO PREVAIL AT MCK AND GLD THROUGH THE TAF PERIOD...BUT ANY MENTION OF SHOWERS AND THUNDERSTORMS HAS BEEN REMOVED. BETWEEN 00Z-06Z...THERE IS A POSSIBILITY OF INCREASING LOWER CLOUDS AS GULF MOISTURE IS TRANSPORTED NORTHWARD INTO THE PLAINS...BUT HAVE HELD OFF ON THIS FOR NOW. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...TL AVIATION...LOCKHART
AREA FORECAST DISCUSSION
NWS JACKSON KY
605 PM EDT THU JUL 9 2015 .UPDATE... ISSUED AT 605 PM EDT THU JUL 9 2015 QUICK UPDATE TO BRING GRIDS IN LINE WITH LATEST RADAR RETURNS. NEXT CLUSTER OF STORMS HAS ENTERED SOUTHWESTERN PORTIONS OF OUR CWA...ALONG WHAT APPEARS TO BE AN OUTFLOW FROM AN EARLIER LINE OF STORMS. SHOWERS AND THUNDERSTORMS ARE DEVELOPING UPSTREAM OF THIS CURRENT CLUSTER OF STORMS AND ALSO APPEAR TO BE MOVING SLIGHTLY NORTH OF EAST ALONG THIS BOUNDARY. ADJUSTED POPS TO EXTRAPOLATE THE CURRENT ACTIVITY THROUGH OUR CWA OVER THE NEXT SEVERAL HOURS AND TO ACCOUNT FOR THE POTENTIAL OF SOME LINGERING SHOWERS THROUGH THE EARLY EVENING. OTHERWISE...ONLY MINOR CHANGES TO THE FORECAST PACKAGE ATTM. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 250 PM EDT THU JUL 9 2015 SIGNIFICANT WIND DAMAGE OCCURRING WITH BOWING SEGMENTS OF STORM COMPLEX CURRENTLY IN THE WEST CENTRAL PART OF THE FORECAST AREA. SEVERE THREAT WILL CONTINUE THROUGH THE REMAINDER OF THE AFTERNOON AS WEAK SURFACE COLD FRONT CONTINUES TO SAG SOUTHEAST ACROSS KY. THE SEVERE THREAT WILL COME TO AN END WITH THE LOSS OF DAYTIME HEATING...AND THE LATEST SHORT RANGE GUIDANCE...INCLUDING THE HRRR SUPPORTS A QUIET NIGHT AHEAD. THE FRONT WILL STALL ACROSS THE AREA LATER TONIGHT...AND YET ANOTHER SHORT WAVE TROUGH WILL MOVE EAST FROM THE CENTRAL PLAINS LATE TONIGHT AND FRIDAY MORNING. THIS WILL BRING ANOTHER GOOD CHANCE OF THUNDERSTORMS FOR FRIDAY. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 250 PM EDT THU JUL 9 2015 FLAT UPPER LEVEL RIDGING CURRENTLY ACROSS THE SOUTHEAST UNITED STATES WILL BUILD WEST INTO THE SOUTHERN PLAINS THIS WEEKEND AND THEN NORTH ACROSS THE PLAINS EARLY NEXT WEEK. WE WILL REMAIN ON THE NORTHWEST PERIPHERY OF THE RIDGE AS WE MOVE INTO NEXT WEEK WITH PERIODIC SHORT WAVES MOVING SOUTHEAST IN NORTHWEST FLOW. WHILE THE SPECIFIC TIMING OF THESE WAVES IS UNCERTAIN AT THIS TIME...THE BOTTOM LINE IS THAT THIS PATTERN WILL RESULT IN A CONTINUED THREAT FOR THUNDERSTORMS EVERY DAY. WITH THE THREAT FOR MCS DEVELOPMENT TO OUR NORTHWEST IN THIS TYPE OF PATTERN THE STORMS WILL NOT NECESSARILY BE TIED TO THE DIURNAL HEATING CYCLE. TEMPERATURES WILL REMAIN NEARLY UNCHANGED THROUGH THE PERIOD WITH HIGHS MOSTLY IN THE MIDDLE AND UPPER 80S AND LOWS IN THE UPPER 60S AND LOWER 70S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 149 PM EDT THU JUL 9 2015 A SLOW MOVING COLD FRONT CONTINUES TO SAG SOUTH ACROSS THE OH VALLEY. SCATTERED STRONG TO SEVERE STORMS ARE OCCURRING AHEAD OF THIS BOUNDARY ACROSS EASTERN KY. THE SEVERE STORMS MOVING OUT OF SOUTH CENTRAL KY SHOULD REMAIN JUST NORTH OF SME AND LOZ...WHILE STORMS AFFECTING SJS WILL BE ENDING SHORTLY. GREATEST THREAT FOR THUNDERSTORMS WILL REMAIN ACROSS THE CENTRAL PART OF THE FORECAST AREA THIS AFTERNOON. THE THUNDERSTORM THREAT WILL DIMINISH AFTER SUNSET...BUT FOG AND LOW CLOUDS ARE EXPECTED TO DEVELOP TONIGHT RESULTING IN IFR CONDITIONS ACROSS MOST OF THE AREA. CONDITIONS WILL GRADUALLY IMPROVE ON FRIDAY...BUT MVFR CEILINGS ARE EXPECTED TO PREVAIL DURING THE MORNING EVEN AFTER VISIBILITY IMPROVES TO 7 OR GREATER MILES. VFR CONDITIONS SHOULD RETURN DURING THE AFTERNOON ON FRIDAY. && .JKL WATCHES/WARNINGS/ADVISORIES...NONE. && $$ UPDATE...RAY SHORT TERM...SBH LONG TERM...SBH AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
251 PM EDT THU JUL 9 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 250 PM EDT THU JUL 9 2015 SIGNIFICANT WIND DAMAGE OCCURRING WITH BOWING SEGMENTS OF STORM COMPLEX CURRENTLY IN THE WEST CENTRAL PART OF THE FORECAST AREA. SEVERE THREAT WILL CONTINUE THROUGH THE REMAINDER OF THE AFTERNOON AS WEAK SURFACE COLD FRONT CONTINUES TO SAG SOUTHEAST ACROSS KY. THE SEVERE THREAT WILL COME TO AN END WITH THE LOSS OF DAYTIME HEATING...AND THE LATEST SHORT RANGE GUIDANCE...INCLUDING THE HRRR SUPPORTS A QUIET NIGHT AHEAD. THE FRONT WILL STALL ACROSS THE AREA LATER TONIGHT...AND YET ANOTHER SHORT WAVE TROUGH WILL MOVE EAST FROM THE CENTRAL PLAINS LATE TONIGHT AND FRIDAY MORNING. THIS WILL BRING ANOTHER GOOD CHANCE OF THUNDERSTORMS FOR FRIDAY. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 250 PM EDT THU JUL 9 2015 FLAT UPPER LEVEL RIDGING CURRENTLY ACROSS THE SOUTHEAST UNITED STATES WILL BUILD WEST INTO THE SOUTHERN PLAINS THIS WEEKEND AND THEN NORTH ACROSS THE PLAINS EARLY NEXT WEEK. WE WILL REMAIN ON THE NORTHWEST PERIPHERY OF THE RIDGE AS WE MOVE INTO NEXT WEEK WITH PERIODIC SHORT WAVES MOVING SOUTHEAST IN NORTHWEST FLOW. WHILE THE SPECIFIC TIMING OF THESE WAVES IS UNCERTAIN AT THIS TIME...THE BOTTOM LINE IS THAT THIS PATTERN WILL RESULT IN A CONTINUED THREAT FOR THUNDERSTORMS EVERY DAY. WITH THE THREAT FOR MCS DEVELOPMENT TO OUR NORTHWEST IN THIS TYPE OF PATTERN THE STORMS WILL NOT NECESSARILY BE TIED TO THE DIURNAL HEATING CYCLE. TEMPERATURES WILL REMAIN NEARLY UNCHANGED THROUGH THE PERIOD WITH HIGHS MOSTLY IN THE MIDDLE AND UPPER 80S AND LOWS IN THE UPPER 60S AND LOWER 70S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 149 PM EDT THU JUL 9 2015 A SLOW MOVING COLD FRONT CONTINUES TO SAG SOUTH ACROSS THE OH VALLEY. SCATTERED STRONG TO SEVERE STORMS ARE OCCURRING AHEAD OF THIS BOUNDARY ACROSS EASTERN KY. THE SEVERE STORMS MOVING OUT OF SOUTH CENTRAL KY SHOULD REMAIN JUST NORTH OF SME AND LOZ...WHILE STORMS AFFECTING SJS WILL BE ENDING SHORTLY. GREATEST THREAT FOR THUNDERSTORMS WILL REMAIN ACROSS THE CENTRAL PART OF THE FORECAST AREA THIS AFTERNOON. THE THUNDERSTORM THREAT WILL DIMINISH AFTER SUNSET...BUT FOG AND LOW CLOUDS ARE EXPECTED TO DEVELOP TONIGHT RESULTING IN IFR CONDITIONS ACROSS MOST OF THE AREA. CONDITIONS WILL GRADUALLY IMPROVE ON FRIDAY...BUT MVFR CEILINGS ARE EXPECTED TO PREVAIL DURING THE MORNING EVEN AFTER VISIBILITY IMPROVES TO 7 OR GREATER MILES. VFR CONDITIONS SHOULD RETURN DURING THE AFTERNOON ON FRIDAY. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...SBH LONG TERM...SBH AVIATION...SBH
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1255 AM CDT THU JUL 9 2015 .UPDATE... ISSUED AT 1254 AM CDT THU JUL 9 2015 UPDATED AVIATION DISCUSSION FOR 06Z TAF ISSUANCE. ALSO UPDATED FORECAST FOR EXPIRATION OF FLASH FLOOD WATCH. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 308 PM CDT WED JUL 8 2015 AFTER COLLABORATING WITH WFO LMK...WILL BE ENDING THE SOUTHEAST PORTION OF THE FLASH FLOOD WATCH EARLY. A FEW SHOWERS HAVE DEVELOPED SO FAR THIS AFTERNOON...BUT THEY HAVE BEEN SHORT- LIVED...AND NOT THE HEAVY RAIN PRODUCERS NEEDED TO WARRANT THE WATCH. THE REMAINDER OF THE WATCH WILL BE LEFT AS IS THROUGH 06Z. THERE IS QUITE A VARIETY OF SOLUTIONS FOR CONVECTIVE TRENDS THROUGH TONIGHT AND INTO THURSDAY. THE HRRR HAS CONSISTENTLY ADVERTISED CONVECTIVE DEVELOPMENT THIS AFTERNOON ALONG DIFFERENTIAL HEATING BOUNDARY FROM WESTERN ARKANSAS THROUGH SOUTH CENTRAL MISSOURI. THIS HAS ALREADY BEGUN OVER ARKANSAS...AND MISSOURI IS PROBABLY NOT GOING TO BE THAT FAR BEHIND. THE NAM AND HRRR INDICATE THAT THIS CONVECTION WILL LIFT NORTH NORTHEAST THROUGH SOUTHEAST MISSOURI AND SOUTHERN ILLINOIS IN THE 00Z-06Z PERIOD. IN BOTH CASES...THE CONVECTION REALLY WEAKENS...IF NOT COMPLETELY DISSIPATES...AS IT REACHES SOUTHWEST INDIANA AND WEST KENTUCKY. THE GFS IS FARTHER NORTHWEST WITH THE MAIN ACTIVITY...AND SPARES MOST OF THE AREA FROM ANY SIGNIFICANT QPF. TRIED TO USE THE NAM/HRRR SOLUTIONS AS A GUIDE THROUGH TONIGHT. CERTAINLY COULD SEE SOME HEAVY RAIN AND FLOODING ISSUES DEVELOP...SO THE NORTHWEST SEGMENT OF THE FLASH FLOOD WATCH LOOKS GOOD THROUGH 06Z. DAMAGING WINDS AND A FEW TORNADOES WILL BE A CONCERN WITH THE CONVECTION THIS EVENING OVER SOUTHEAST MISSOURI AND SOUTHERN ILLINOIS. FOR THURSDAY THE MODELS ALL DRAPE THE FRONT ACROSS WEST KENTUCKY AND SOUTHERN PORTIONS OF SOUTHEAST MISSOURI. THE NAM DEVELOPS AND HOLDS ONTO WEAKER CONVECTION ALONG THIS BOUNDARY THROUGH MUCH OF THE DAY. CANNOT RULE OUT FURTHER HEAVY RAIN NEAR THE FRONT THURSDAY. THE BOUNDARY WILL LIFT BACK TO THE NORTH THURSDAY NIGHT...AND SOME SCATTERED CONVECTION WILL BE POSSIBLE ALONG IT...MAINLY OVER SOUTHEAST MISSOURI AND SOUTHERN ILLINOIS. HEADING INTO FRIDAY AND FRIDAY NIGHT...ALL INDICATIONS ARE THAT AN UPPER RIDGE WILL BE BUILDING OVERHEAD FROM THE SOUTHWEST FRIDAY INTO FRIDAY NIGHT...AND THIS SHOULD EVENTUALLY PUT AN END TO THE CONVECTION FOR AWHILE. THERE IS SOME DISCREPANCY IN HOW QUICKLY THIS WILL HAPPEN...AND THAT WILL LEAVE THE DOOR OPEN FOR CONVECTION ALONG THE NORTHEAST PERIPHERY OF THE REGION FRIDAY AND FRIDAY NIGHT. FOR NOW WILL LEAVE A SMALL POP FOR FRIDAY...BUT WILL KEEP FRIDAY NIGHT DRY. TEMPERATURES WILL BE DEPENDENT ON CONVECTIVE TRENDS THROUGH THURSDAY...BUT IT WILL BE GETTING HOT BY FRIDAY WITH MUCH OF THE AREA INTO THE LOWER 90S. .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 308 PM CDT WED JUL 8 2015 ECMWF, GFS AND CANADIAN SHOW AN UPPER LEVEL HIGH PRESSURE SYSTEM OVER THE SOUTHEAST UNITED STATES SLOWLY SLIDING WEST THROUGH THE WEEKEND, MOVING OVER THE TEXAS PANHANDLE BY 12Z MONDAY. CONDITIONS WILL REMAIN DRY AND HOT SATURDAY INTO SATURDAY NIGHT, THOUGH AN ISOLATED SHOWER OR STORM IS NOT COMPLETELY OUT OF THE QUESTION SATURDAY AFTERNOON. AS THE HIGH SHIFTS FARTHER WEST, AN UPPER LEVEL LOW WILL DEVELOP OVER THE GREAT LAKES REGION SUNDAY. MODELS ALL SHOW A MORE PRONOUNCED TROF GRADUALLY DEVELOPING SOUTHWESTWARD MONDAY INTO TUESDAY. CHANCES OF SHOWERS AND THUNDERSTORMS SHOULD RETURN TO OUR NORTHEAST HALF OF COUNTIES SUNDAY NIGHT, WITH CHANCES INCREASING AND EXPANDING SOUTHWEST MONDAY INTO TUESDAY. WINDS WILL CONTINUE TO BE OUT OF THE SOUTHWEST SATURDAY THROUGH MONDAY NIGHT, WHICH WILL CONTINUE TO PUMP WARM MOIST AIR INTO OUR REGION. HEAT INDEX READINGS WILL REACH THE UPPER 90S TO AROUND 100 DEGREES. BY TUESDAY INTO TUESDAY NIGHT, A WEAK SURFACE LOW WILL MOVE JUST EAST OF OUR AREA, AND WINDS WILL SHIFT TO THE NORTHWEST. THIS WILL HELP TEMPERATURES DROP BACK A FEW DEGREES TUESDAY INTO WEDNESDAY. AS THE UPPER TROF AND WEAK SURFACE LOW MOVE SOUTHEAST, SHOWER AND THUNDERSTORM CHANCES WILL BEGIN SLOWLY TAPERING OFF FROM THE NORTHWEST TUESDAY NIGHT INTO WEDNESDAY. && .AVIATION... ISSUED AT 1254 AM CDT THU JUL 9 2015 WITH A BOUNDARY IN THE VICINITY...MAINTAINED MENTION OF SHOWERS AND TEMPO THUNDERSTORMS THROUGH MUCH OF THE NIGHT AT ALL FORECAST TERMINALS. BY LATE NIGHT AND INTO THE MORNING HOURS...A TREND TOWARDS MVFR CEILINGS IS ANTICIPATED. AT THIS POINT...WE BELIEVE THE MVFR CEILINGS WILL BE SLOW TO LIFT UNTIL AFTERNOON...WHICH WOULD PUT A DAMPER ON ANY DIURNAL STORM DEVELOPMENT. IF MORE SUNSHINE MATERIALIZES...WE MAY NEED TO ADD A MENTION OF AFTERNOON THUNDERSTORMS IN LATER FORECASTS. SOUTHWEST WINDS WILL SWING AROUND TO THE WEST AROUND 10 KNOTS BY MORNING. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1048 PM CDT FRI JUL 10 2015 .UPDATE: ISSUED AT 1009 PM CDT FRI JUL 10 2015 SHORT RANGE MODELS INCLUDING THE HRRR AND RAP AND NEW 00Z NAM ARE SHOWING AN INCREASING LIKELIHOOD FOR WARM ADVECTION SHOWERS AND THUNDERSTORMS OVERNIGHT. ALL MODELS ARE DEVELOPING A MODEST LOW LEVEL JET WITH ISENTROPIC LIFT OVER THE WARM FRONT WHICH IS NOW ALMOST BISECTING THE AREA ALONG THE MISSISSIPPI RIVER. DECENT 850MB MOISTURE CONVERGENCE ALONG WITH THE VORTMAX LEFT OVER FROM CONVECTION EARLIER IN THE DAY SHOULD BE ENOUGH TO TOUCH OFF CONVECTION. HAVE BUMPED UP POPS TO MID-HIGH CHANCE AND EVEN LIKELY UP ACROSS NORTHEAST MISSOURI AND WEST CENTRAL ILLINOIS AS A RESULT. CARNEY && .SHORT TERM: (THROUGH TONIGHT) ISSUED AT 346 PM CDT FRI JUL 10 2015 UPPER LVL RIDGE BEGINS TO DVLP ACROSS THE CNTRL CONUS WITH A SUBTLE SHORT WAVE TOPPING THE RIDGE. BNDRY THAT HAS BEEN STUCK ACROSS THE AREA FOR SEVERAL DAYS IS FCST TO FINALLY START MVNG TONIGHT IN RESPONSE TO THE APPROACHING SHORT WAVE. THERE SHOULD BE ONGOING ISLD/SCTTRD CONVECTION ALONG THE BNDRY AT THE BEGINNING OF THE PRD. CONVECTION SHOULD CONTINUE TO PERCOLATE THRU THE NIGHT AS THE FRONT CONTINUES LIFTING NORTH THRU THE AREA. BEST CHNACE/COVERAGE APPEARS TO BE LATE TONIGHT ACROSS NE MO AS A TSTM COMPLEX THAT DVLPD ACROSS ERN KS/NE AND NW MO/WRN IA THIS EVNG TRACKS NE. 2% .LONG TERM: (SATURDAY THROUGH NEXT FRIDAY) ISSUED AT 346 PM CDT FRI JUL 10 2015 SATURDAY THRU SUNDAY NIGHT N/NE/E SECTIONS OF THE CWA WILL BE ON THE STHRN EDGE OF THE STORM TRACK THRU THE WKND WHICH MEANS THERE WILL BE ONGOING CHANCES FOR PRECIP IN THOSE AREAS THRU THE WKND. CONVECTION SHOULD LIFT NE BY MID/LATE MRNG. UPPER LVL RIDGE CONTINUES TO EXPAND AND STRENGTHEN ACROSS THE PLAINS THOUGH THERE WILL BE A CHANCE FOR ISLD/SCTTRD CONVECTION N/NE/E OF THE STL METRO AREA DRNG THE PM HRS. ANOTHER TSTM COMPLEX IS FCST TO TRACK NORTH OF THE AREA SAT NIGHT WHICH MAY ALSO BRUSH THE N/NE SECTIONS OF THE CWA. THIS ACTIVITY IS EXPECTED TO EXIT THE FA BY LATE MRNG WITH ANOTHER COMPLEX POSSIBLE SUN NIGHT WHICH MAY CLIP AREAS FROM NE MO/W CNTRL IL TO S CNTRL IL...BUT THIS SCENARIO IS LOWER CONFIDENCE THAN TONIGHT OR SAT NIGHT/S COMPLEX AND IF IT DOES HAPPEN WILL LIKELY BE EVEN FARTHER NE THAN THE PREVIOUS TWO NIGHTS. WARMER TEMPS ARE ALMOST A CERTAINTY THIS WKND. A WARM AND MOIST AIRMASS WILL MOVE IN BEHIND THE WARM FRONT SAT AND CONTINUE INTO NEXT WEEK. HIGHS ARE EXPECTED TO BE IN THE MID 80 TO MID 90S ON SAT WITH LOW/MID 90S AREA WIDE ON SUN. THE COOLER TEMPS ON SUN WILL BE ACROSS NE MO/W CNTRL IL SE INTO S CNTRL IL WHERE MORE CLOUDS AND POTENTIAL PRECIP ARE EXPECTED TO HOLD TEMPS DOWN SLIGHTLY. DPS ARE ALSO FCST TO BE WELL INTO THE 70S MAKING FOR A MUGGY WKND. WENT AT OR ABOVE THE WARMEST GUIDANCE THRU THE WKND EXCEPT IN THE STL METRO ARE ON SUN WHERE USED MORE OF A BLEND. DIDN`T WANT TO GO WITH THE UPPER 90S THAT THE MAV IF FCSTNG JUST YET. MONDAY THROUGH FRIDAY UPPER RIDGE RETROGRADES SLIGHTLY WEST BY EARLY NEXT WEEK PUTTING THE CWA INTO NW FLOW. THE UPPER FLOW TRANSITIONS TO MORE OF A ZONAL FLOW BY MID WEEK WHICH SHOULD CONTINUE THRU THE END OF THE WEEK. THIS MEANS THAT THE N/NE/E PORTION OF THE CWA WILL REMAIN NEAR THE STHRN EDGE OF THE STORM TRACK THRU THE WEEK. A SHORT WAVE TOPS THE RIDGE SUNDAY NIGHT/MON MRNG PASSING THRU THE FA MON NIGHT. THIS ENERGY SHOULD INITIATE TSTM DVLPMNT...BUT IT IS A BIT EARLY TO PIN DOWN THE EXACT LOCATION THIS FAR UT BUT SPC HAS THE NERN PORTION OF THE CWA IN THEIR DAY 4 OUTLOOK. A COLD FRONT ASSOC WITH THE SHORT WAVE IS FCST TO APPROACH THE NW FA LATE MON AND APPEARS TO GET HUNG UP ACROSS THE CWA THRU THE MIDDLE OF THE WEEK BEFORE LIFTING BACK NORTH BY THE END OF THE WEEK. THE BNDRY IN THE AREA MEANS DAILY CHANCES FOR CONVECTION THOUGH THE BEST CHANCES WILL REMAIN ACROSS THE N/NE/E PORTION OF THE FA DUE TO COOLER MID LVL TEMPS AND PROXIMITY TO THE STORM TRACK. TEMPS ARE EXPECTED TO REMAIN NEAR SEASONAL LVLS IN THE MID 80S TO LOWER 90S. DPS ARE FCST TO BE IN THE 70S THRU THE WEEK. THE BNDRY SHOULD HELP POOL THE DPS DRNG THE MIDDLE OF THE WEEK WITH SEVERAL MODELS HINTING AT 80 DEGREE DPS. NOT READY TO BUY INTO THAT SOLUTION BUT SEEMS PLAUSIBLE DUE TO THE WET SOIL MOISTURE CONDITIONS AND EVAPOTRANSPORTION IN HIGH GEAR. 2% && .AVIATION: (FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1039 PM CDT FRI JUL 10 2015 SHORT RANGE MODELS (RAP, HRRR) ARE AGREEING THE SHOWERS AND THUNDERSTORMS WILL DEVELOP ALONG THE WARM FRONT AS IT MOVES NORTH OVERNIGH. THE ATMOSPHERE LOOK BEST OR UIN WHERE THERE APPEARS TO BE BETTER DEEP MOISTURE CONVERGENCE. TIMEING ON CURRENT TAF LOOKS GOOD WITH SHROT RANGE MODELS SO WILL CHANGE PROB30 TO A TEMPO GROUP. A VCSH FOR COU MAY BE ALL THAT IS NEEDED FOR A COUPLE OF HOURS AS IT LOOKS LIKE THE DEVELOPMENT WILL BE NORTH AND EAST. WILL BRING THE FRONT THROUGH COU AT 14Z AND UIN AND 18Z. SPECIFICS FOR KSTL: RAP AND HRRR DEVELOP PRECIPITATON NW-SE ALONG THE ADVANCING WARM FRONT. IF IT HAPPENS IT LOOKS TO BE 10Z TO 14Z. STILL, CONFIDENCE IS NOT HIGH ENOUGH TO GO ABOVE VICINITY FOR NOW. WILL DELAY THE WIND SHIFT WITH THE WARM FRONT TO 18Z FOLLWING THE RAP/HRRR. JPK && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1021 PM CDT FRI JUL 10 2015 .UPDATE: ISSUED AT 1009 PM CDT FRI JUL 10 2015 SHORT RANGE MODELS INCLUDING THE HRRR AND RAP AND NEW 00Z NAM ARE SHOWING AN INCREASING LIKELIHOOD FOR WARM ADVECTION SHOWERS AND THUNDERSTORMS OVERNIGHT. ALL MODELS ARE DEVELOPING A MODEST LOW LEVEL JET WITH ISENTROPIC LIFT OVER THE WARM FRONT WHICH IS NOW ALMOST BISECTING THE AREA ALONG THE MISSISSIPPI RIVER. DECENT 850MB MOISTURE CONVERGENCE ALONG WITH THE VORTMAX LEFT OVER FROM CONVECTION EARLIER IN THE DAY SHOULD BE ENOUGH TO TOUCH OFF CONVECTION. HAVE BUMPED UP POPS TO MID-HIGH CHANCE AND EVEN LIKELY UP ACROSS NORTHEAST MISSOURI AND WEST CENTRAL ILLINOIS AS A RESULT. CARNEY && .SHORT TERM: (THROUGH TONIGHT) ISSUED AT 346 PM CDT FRI JUL 10 2015 UPPER LVL RIDGE BEGINS TO DVLP ACROSS THE CNTRL CONUS WITH A SUBTLE SHORT WAVE TOPPING THE RIDGE. BNDRY THAT HAS BEEN STUCK ACROSS THE AREA FOR SEVERAL DAYS IS FCST TO FINALLY START MVNG TONIGHT IN RESPONSE TO THE APPROACHING SHORT WAVE. THERE SHOULD BE ONGOING ISLD/SCTTRD CONVECTION ALONG THE BNDRY AT THE BEGINNING OF THE PRD. CONVECTION SHOULD CONTINUE TO PERCOLATE THRU THE NIGHT AS THE FRONT CONTINUES LIFTING NORTH THRU THE AREA. BEST CHNACE/COVERAGE APPEARS TO BE LATE TONIGHT ACROSS NE MO AS A TSTM COMPLEX THAT DVLPD ACROSS ERN KS/NE AND NW MO/WRN IA THIS EVNG TRACKS NE. 2% .LONG TERM: (SATURDAY THROUGH NEXT FRIDAY) ISSUED AT 346 PM CDT FRI JUL 10 2015 SATURDAY THRU SUNDAY NIGHT N/NE/E SECTIONS OF THE CWA WILL BE ON THE STHRN EDGE OF THE STORM TRACK THRU THE WKND WHICH MEANS THERE WILL BE ONGOING CHANCES FOR PRECIP IN THOSE AREAS THRU THE WKND. CONVECTION SHOULD LIFT NE BY MID/LATE MRNG. UPPER LVL RIDGE CONTINUES TO EXPAND AND STRENGTHEN ACROSS THE PLAINS THOUGH THERE WILL BE A CHANCE FOR ISLD/SCTTRD CONVECTION N/NE/E OF THE STL METRO AREA DRNG THE PM HRS. ANOTHER TSTM COMPLEX IS FCST TO TRACK NORTH OF THE AREA SAT NIGHT WHICH MAY ALSO BRUSH THE N/NE SECTIONS OF THE CWA. THIS ACTIVITY IS EXPECTED TO EXIT THE FA BY LATE MRNG WITH ANOTHER COMPLEX POSSIBLE SUN NIGHT WHICH MAY CLIP AREAS FROM NE MO/W CNTRL IL TO S CNTRL IL...BUT THIS SCENARIO IS LOWER CONFIDENCE THAN TONIGHT OR SAT NIGHT/S COMPLEX AND IF IT DOES HAPPEN WILL LIKELY BE EVEN FARTHER NE THAN THE PREVIOUS TWO NIGHTS. WARMER TEMPS ARE ALMOST A CERTAINTY THIS WKND. A WARM AND MOIST AIRMASS WILL MOVE IN BEHIND THE WARM FRONT SAT AND CONTINUE INTO NEXT WEEK. HIGHS ARE EXPECTED TO BE IN THE MID 80 TO MID 90S ON SAT WITH LOW/MID 90S AREA WIDE ON SUN. THE COOLER TEMPS ON SUN WILL BE ACROSS NE MO/W CNTRL IL SE INTO S CNTRL IL WHERE MORE CLOUDS AND POTENTIAL PRECIP ARE EXPECTED TO HOLD TEMPS DOWN SLIGHTLY. DPS ARE ALSO FCST TO BE WELL INTO THE 70S MAKING FOR A MUGGY WKND. WENT AT OR ABOVE THE WARMEST GUIDANCE THRU THE WKND EXCEPT IN THE STL METRO ARE ON SUN WHERE USED MORE OF A BLEND. DIDN`T WANT TO GO WITH THE UPPER 90S THAT THE MAV IF FCSTNG JUST YET. MONDAY THROUGH FRIDAY UPPER RIDGE RETROGRADES SLIGHTLY WEST BY EARLY NEXT WEEK PUTTING THE CWA INTO NW FLOW. THE UPPER FLOW TRANSITIONS TO MORE OF A ZONAL FLOW BY MID WEEK WHICH SHOULD CONTINUE THRU THE END OF THE WEEK. THIS MEANS THAT THE N/NE/E PORTION OF THE CWA WILL REMAIN NEAR THE STHRN EDGE OF THE STORM TRACK THRU THE WEEK. A SHORT WAVE TOPS THE RIDGE SUNDAY NIGHT/MON MRNG PASSING THRU THE FA MON NIGHT. THIS ENERGY SHOULD INITIATE TSTM DVLPMNT...BUT IT IS A BIT EARLY TO PIN DOWN THE EXACT LOCATION THIS FAR UT BUT SPC HAS THE NERN PORTION OF THE CWA IN THEIR DAY 4 OUTLOOK. A COLD FRONT ASSOC WITH THE SHORT WAVE IS FCST TO APPROACH THE NW FA LATE MON AND APPEARS TO GET HUNG UP ACROSS THE CWA THRU THE MIDDLE OF THE WEEK BEFORE LIFTING BACK NORTH BY THE END OF THE WEEK. THE BNDRY IN THE AREA MEANS DAILY CHANCES FOR CONVECTION THOUGH THE BEST CHANCES WILL REMAIN ACROSS THE N/NE/E PORTION OF THE FA DUE TO COOLER MID LVL TEMPS AND PROXIMITY TO THE STORM TRACK. TEMPS ARE EXPECTED TO REMAIN NEAR SEASONAL LVLS IN THE MID 80S TO LOWER 90S. DPS ARE FCST TO BE IN THE 70S THRU THE WEEK. THE BNDRY SHOULD HELP POOL THE DPS DRNG THE MIDDLE OF THE WEEK WITH SEVERAL MODELS HINTING AT 80 DEGREE DPS. NOT READY TO BUY INTO THAT SOLUTION BUT SEEMS PLAUSIBLE DUE TO THE WET SOIL MOISTURE CONDITIONS AND EVAPOTRANSPORTION IN HIGH GEAR. 2% && .AVIATION: (FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 530 PM CDT FRI JUL 10 2015 WARM FRONT FORECAST TO SLOWLY LIFT NORTH ACROSS THE AREA BY 18Z SAT. GFS IS A BIT FASTER THAN NAM BY ABOUT 3 HOURS. NO STRONG FEELING AS TO WHICH IS RIGHT SO WILL COMPROMISE THE TIMING. BEST CHANCE FOR STORMS LOOKS TO BE ACROSS NORTHEAST MO AND WEST CEMTRAL IL WITH COU IN THE MIX AS WELL. PROB30 LOOKS GOOD FOR UIN AND VICINITY FOR COU. OTHER QUESTION IS WILL STRATUS AND FOG REDEVELOP BEFORE THE FRONT MOVES THROUGH. AS USUAL NAM HITS THIS HARDER THAN THE GFS. GIVEN THAT THE NAM WAS BETTER WITH THE CLOUDS LATE THIS AFTERNOON WILL GO WITH IT BUT WILL BACK OFF A BIT THAN THE PREVIOUS FORECAST. GIVEN THE LOCATION THE FRONT MIDDAY SAT AT LEAST A VICINITY MAY BE NEEDED AT UIN. SPECIFICS FOR KSTL: EXACT POSITION OF THE FRONT FOR SAT AM DIFFICULT TO NAIL DOWN. THE RANGE ACCORDING TO THE GUIDANCE IS THROUGH STL EITHER BY 15Z WITH THE GFS AND 18Z. SOMEWHERE IN BETWEEN APPEARS TO BE A GOOD SOLUTION. WILL STRATUS REDEVELOP? LATEST GUIDANCE IS NOT AS HIGH ON THIS SCENARIO. WILL LEAVE A BRIEF PERIOD IN FOR NOW PER THE PREVIOUS FORECAST BUT WILL LOOK MORE CLOSELY AT THIS THROUGH THE EVENING. BEST CHANCE FOR TSRA WOULD LIKELY BE 10-14Z. CHANCES LOW SO WILL CONTINUE THE DRY FORECAST. JPK && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1117 PM CDT Wed Jul 8 2015 .SHORT TERM...(This Evening through Thursday) Issued at 100 PM CDT WED JUL 8 2015 Main near term concern is the chances for renewed convective development over the eastern cwfa. A pocket of somewhat higher instability has developed over south central MO where sfc temperatures have risen into the low-mid 80s. Progged RUC instability of 500-1000 j/kg is expected in this area this afternoon. High resolution models are tending to intensify convection along/ahead of the ongoing showers, at least on a scattered basis. A continued strong low level inflow/jet will enhance low level helicity with the potential of stronger storms/low topped supercells. Already seeing weak rotation with convection in the northeast cwfa. Helicity may be enhanced by west- east warm front over central/east central MO. HRRR develops somewhat stronger updrafts toward 21z-22z and then on into the early evening. Some sw-ne training of convection may occur over our eastern counties as well early this evening. .LONG TERM...(Thursday Night through Wednesday) Issued at 100 PM CDT WED JUL 8 2015 Another shortwave is progged to move into eastern KS late in the day with further chances for renewed precip into Thu night. In general, better precip chances will then shift north of the area for a bit as an upper level ridge works it`s way over the region Fri-Sat-Sun. Very warm/hot/steamy weather is then expected Fri into early next week. First look at general guidance has low 90s for highs for this time frame (Fri-Mon). Active weather then may occur again by Tue-Wed as the upper pattern amplifies as a ridge builds over Rockies and we are under upper level nw flow. Hard to get too detailed yet out that far. && .AVIATION...(For the 06Z TAFS through 06Z Thursday Night) Issued at 1112 PM CDT WED JUL 8 2015 IFR conditions developing this evening across the forecast area in the wake of showers and thunderstorms earlier. Ceilings have dipped at or below 1500 feet with visibilities starting to decrease to around 3 miles at SGF. Scattered showers starting to develop along a boundary stretching from near BBG into northeast OK. Have gone with VCSH wording at BBG taf overnight. IFR conditions expected at all 3 sites. Convection will expand northward on Thursday with scattered showers/thunderstorms expected during the afternoon/evening at the 3 taf sites. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...FLASH FLOOD WATCH until 1 AM CDT Thursday FOR MOZ082-083-096>098- 104>106. KS...NONE. && $$ SHORT TERM...DSA LONG TERM...DSA AVIATION...Lindenberg
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
548 PM MDT FRI JUL 10 2015 .AVIATION... 00Z TAF CYCLE HIT AND MISS SH/TS WILL REMAIN ACROSS MOST OF THE AREA THROUGH THE EARLY/MID EVENING. THEN MAIN FOCUS SHOULD SHIFT TOWARDS THE SE PLAINS DURING THE REST OF THE OVERNIGHT. HITTING ROW TERMINAL FORECAST HARD WITH SH/TS IMPACTS. ANOTHER CROP OF STORMS SHOULD FORM BY 18Z SATURDAY. SATURDAY/S CROP SHOULD BE A LITTLE LESS THAN WHAT OCCURRED TODAY WITH A LITTLE DRIER TREND NEAR THE AZ STATE LINE. USED VCSH/VCTS AT THIS TIME FOR SATURDAY AFTERNOON/S ACTIVITY. THE BEST CHANCE OF MVFR CIGS DUE TO PASSING STORMS WOULD BE AT TCC/ROW NEAR TERM AND THEN ROW LATER TONIGHT. 50 && .PREV DISCUSSION...304 PM MDT FRI JUL 10 2015... .SYNOPSIS... SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE WEEKEND AS THE MONSOON MOISTURE PLUME STRETCHES FROM SOUTH TO NORTH OVER THE STATE. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE WITH ANY OF THE STRONGER STORMS...ALONG WITH GUSTY WINDS AND SMALL HAIL. UPPER LEVEL HIGH PRESSURE WILL DRIFT WEST THROUGH NEXT WEEK AND ALLOW FOR DRIER AND HOTTER CONDITIONS TO RETURN. ISOLATED TO SCATTERED SHOWERS AND STORMS WILL STILL DEVELOP AROUND THE HIGH TERRAIN... ESPECIALLY OVER WESTERN NEW MEXICO. && .DISCUSSION... AN UNSEASONABLY DEEP UPPER LEVEL LOW OVER THE GREAT BASIN IS FORCING A STRONG 40-60KT UPPER JET OVER AZ/NM. A 594DM H5 UPPER HIGH DRIFTING WEST OVER EAST TX IS TAPPING A JUICY ATMOSPHERE FROM MEXICO AND SHIFTING IT NORTHWARD INTO THE FASTER UPPER LEVEL FLOW. STRONG DIFFLUENCE AND TERRAIN CIRCULATIONS WITH AFTERNOON HEATING IN THIS PATTERN IS FORCING SEVERAL STRONG TO EVEN SEVERE STORMS ACROSS THE SW PORTION OF THE STATE. OTHERWISE STORM COVERAGE IS LESS TODAY AND ACTIVITY IS BUMPING ALONG QUICKLY FOR JULY...THUS LIMITING THE FLASH FLOOD THREAT. HRRR GUIDANCE SHOWS CONVECTIVE ACTIVITY MAKING IT INTO THE RIO GRANDE VALLEY AND EASTERN PLAINS BETWEEN 3PM AND 7PM. NOT MUCH CHANGE ANTICIPATED SATURDAY WITH THE OVERALL CIRCULATION PATTERN REMAINING QUASI-STATIONARY. STORM MOTIONS MAY BECOME A BIT MORE SOUTH TO NORTH AS THE UPPER HIGH DRIFTS WEST AND IMPINGES ON THE UPPER LEVEL SW FLOW. BY SUNDAY...ANOTHER BURST IS ADVERTISED BY MID-RANGE MODEL GUIDANCE. INCREASED POPS AGAIN SUNDAY WITH LOCALLY HEAVY RAINFALL THREAT INCREASING. FOR THE REMAINDER OF NEXT WEEK... A SLOW DRYING AND WARMING TREND IS ON TAP. HIGH TEMPS WILL TREND TO NEAR NORMAL WITH SLOW-MOVING STORMS FAVORING HIGH TERRAIN AREAS. GUYER && .FIRE WEATHER... DAILY ROUNDS OF WETTING RAIN IN THE FORM OF THUNDERSTORMS AND SHOWERS WILL CONTINUE THROUGH THE FORECAST PERIOD...THOUGH COVERAGE WILL LIKELY DECREASE AS DRIER AND WARMER CONDITIONS DEVELOP. BY EARLY NEXT WEEK...EASTERN ZONES WILL SEE THE FEWEST STORMS WHILE WESTERN AND CENTRAL ZONES REMAIN MORE ACTIVE. TEMPERATURES WILL FINALLY REACH NORMAL OR HIGHER LEVELS ACROSS THE EAST BY SUNDAY AND MUCH OF THE STATE BY THURSDAY. VENTILATION LOOKS TO BE GENERALLY GOOD TO EXCELLENT MOST DAYS WITH LOWER VALUES...AND SOME AREAS OF POOR TO FAIR VENTILATION ON SUNDAY AND THURSDAY. INTERESTING PATTERN FOR JULY WITH AN UNSEASONABLY DEEP CLOSED LOW POSITIONED CENTERED OVER THE GREAT BASIN AND THE ASSOCIATED UPPER JET EXTENDED FROM NORTHERN BAJA...ACROSS ARIZONA AND OVER NORTHWEST NEW MEXICO. SHOWERS AND THUNDERSTORMS THIS AFTERNOON ARE MOVING FAIRLY QUICKLY TO THE NORTHEAST...AND SOME ARE PRODUCING HAIL AND LOCALLY HEAVY RAIN. LOWER DEWPOINTS NOTED OVER ARIZONA THIS MORNING HAVE NOT REALLY TRANSLATED INTO WESTERN ZONES TODAY. THUS... OVERNIGHT RH RECOVERIES LOOK TO BE GOOD TO EXCELLENT ALL ZONES. MEANWHILE...UPPER LEVEL HIGH PRESSURE CONTINUES TO BUILD OVER THE SOUTHEAST STATES...MAINTAINING THE FLUX OF MONSOON MOISTURE FROM MEXICO INTO NEW MEXICO. MODELS CONTINUE TO DEPICT THE UPPER HIGH BUILDING OVER TEXAS...RESULTING IN A WESTWARD NUDGE OF THE MONSOON PLUME. SATURDAY LOOKS TO BE FAIRLY ACTIVE MOST ZONES...WITH THE EXTREME NORTHWEST AND NORTHEAST CORNERS LEAST FAVORED. BY SUNDAY THROUGH TUESDAY...EASTERN ZONES LOOK TO REMAIN FAIRLY DRY WITH THE HIGH TERRAIN OF WESTERN AND CENTRAL ZONES FAVORED. 05 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 50
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1001 AM EDT THU JUL 9 2015 .SYNOPSIS... A MOIST QUICK HITTING SYSTEM WILL BRING A WAVE OF RAIN TO THE REGION THIS AFTERNOON THROUGH EVENING. ACROSS THE SOUTHERN FINGER LAKES AND SOUTHERN TIER TO WESTERN CATSKILLS OF NEW YORK...AND ALL OF NORTHEAST PENNSYLVANIA...THERE WILL ALSO BE EMBEDDED THUNDERSTORMS AND RAINFALL COULD BE HEAVY AT TIMES. AFTER THE SYSTEM EXITS LATE TONIGHT...WELCOME DRY WEATHER IS EXPECTED FRIDAY THROUGH MOST IF NOT ALL OF THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... 945 AM UPDATE... UPDATED TO SPEED UP THE ARRIVAL OF THE RAINS BY 1-2 HOURS AS PER LATEST RADAR TRENDS. THE HRRR SEEMS TO HAVE THE BEST HANDLE ON TIMING WITH THE RAP...WRF_NMM AND WRF_ARW ALSO PRETTY CLOSE. THE NAM12 BEGINS SLOW BUT CATCHES UP AND BRINGS A BATCH OF PRECIP ACRS OUR FORECAST AREA BY 16-20Z. STILL APPEARS HEAVIEST RAIN FALLS BTWN 18Z AND 23Z. BASIN AVE QPF AMNTS STILL LOOK TO BE 1-2 INCHES IN OUR CENTRAL COUNTIES AS ADVERTISED BUT CONVECTION ALLOWING MODELS SHOW MUCH NARROWER STRIPES OF HEAVIER RAIN AS ONE WUD EXPECT. A STRIPE OF 3-5 INCHES WILL BE POSSIBLE OVER A SMALLER AREA AND HENCE THE FLASH FLOOD WATCH. IT STILL APPEARS BEST POTENTIAL WILL BE ACRS THE TWIN-TIER REGION BUT FARTHER S THERE WILL BE A SEVERE WEATHER THREAT WITH HEAVY RAINS TOO AS PWATS ARE OVER 2 INCHES!! THERE ARE BREAKS IN THE VIS SATELLITE IN NE PA AND MODELS SHOW CAPE BUILDING UP WITH THE DAY/S HEATING IN NE PA. WITH THE SFC LOW TRACK JUST N OF NE PA...THIS AREA WILL SEE VERY HIGH LL WIND SHEAR. 0-1 KM BULK SHEAR IS PROGGED TO RANGE AROUND 25 KNOTS...WITH 0-1 KM HELICITY AT KAVP ON THE 6Z NAM AT 242 M2/S2 THIS AFTERNOON. MIXED CAPES REACHING CLOSE TO 1000 J/KG. THE 6Z NAM JOGGED THE SFC LOW TO THE N AND THAT IS WHY KAVP/S SOUNDING LOOKS SO IMPRESSIVE. BUT THIS SIGNALS THAT OUR SOUTHERN ZONES ARE VERY CLOSE TO A SIGNIFICANT SVR WEATHER THREAT LATER TODAY. THIS CUD BE A MINI-SUPERCELL TORNADO DAY AND WE CONCUR WITH THE ENHANCED RISK JUST TO OUR SRN BRDR COUNTIES FROM SPC. PREVIOUS DSCN IS BELOW. 430 AM UPDATE... MAIN CONCERNS ARE POTENTIAL FOR FLASH FLOODING FROM SOUTHERN FINGER LAKES AND SOUTHERN TIER TO WESTERN CATSKILLS IN NY AND ALL OF NORTHEAST PA...AND ALSO THREAT OF SEVERE THUNDERSTORMS MAINLY NORTHEAST PA. SHORTWAVE IS CURRENTLY LIFTING THROUGH THE AREA PRIOR TO DAWN...BUT ONLY WITH VERY LIGHT SHOWERS AND/OR DRIZZLE TO SHOW FOR IT IN THE POCONOS TO SULLIVAN COUNTY NY...VIRGA ELSEWHERE DUE TO DRY AIR IN THE 6-14 KFT AGL LAYER. THAT WAVE WILL QUICKLY EXIT AND LEAVE US TEMPORARILY QUIET THIS MORNING. THIS AFTERNOON INTO EVENING...STRONGER WAVE WILL ZIP THROUGH THE AREA AS WAVE OF LOW PRESSURE TRACKS ROUGHLY ALONG THE NY-PA BORDER BEFORE SHUNTING FURTHER SOUTHEAST TOWARDS LONG ISLAND. THIS SYSTEM HAS A LOT GOING FOR IT IN REGARDS TO A THREAT FOR FLASH FLOODING...MOST IMPORTANTLY PRECIPITABLE WATER SURGING IN EXCESS OF 2 INCHES TO ABOUT 200 PERCENT OF NORMAL. STRONG LOW LEVEL JET 40-50 KTS WILL BE RESPONSIBLE FOR TRANSPORTING THIS MOISTURE...MEANWHILE ALOFT WE GET FORCED ASCENT VIA RIGHT ENTRANCE REGION OF STRENGTHENING UPPER JET AT 250-300MB. ADD WELL MARKED SURFACE BOUNDARY-SURFACE LOW...AND ALREADY MOIST SOILS DUE TO REPEATED RAINS OF THE LAST FEW WEEKS...AND INGREDIENTS ARE COMING TOGETHER. FREEZING LEVEL IS ACTUALLY EXCEEDING 15 KFT AGL...WHICH WILL YIELD VERY EFFICIENT RAIN. 1 HOUR FLASH FLOOD GUIDANCE FOR MUCH OF THE AREA OF CONCERN /THE AMOUNT OF RAIN IT WOULD TAKE IN AN HOUR TO START CAUSING FLOOD PROBLEMS/...IS ONLY 0.8 TO 1.4 INCHES. THIS SYSTEM ALREADY HAS A HISTORY OF FLASH FLOODING INCLUDING CURRENT FLOODING IN PORTIONS OF IL-IN- KY. BASED ON THE ABOVE FACTORS...IN COORDINATION WITH SURROUNDING OFFICES...WE HAVE HOISTED A FLASH FLOOD WATCH FOR SOUTHERN TIER- SOUTHERN FINGER LAKES-WESTERN CATSKILLS OF NY...AND ALL OF NORTHEAST PA THIS AFTERNOON INTO TONIGHT. COUNTIES IMMEDIATELY NORTH MAY ALSO EXPERIENCE HEAVY RAINFALL IF THE SYSTEM TRACK CHANGES JUST SLIGHTLY...IN WHICH CASE THE WATCH COULD BE EXPANDED. UNFORTUNATELY...WE ALSO HAVE A SEVERE WEATHER THREAT FOR AT LEAST NORTHEAST PA. LIMITING FACTOR WILL BE HOW MUCH CAPE WE CAN MANAGE CONSIDERING CLOUD COVER...BUT MODEL CONSENSUS WOULD SUGGEST SOMEWHERE IN THE 500-900 J/KG RANGE TOWARDS WYOMING VALLEY WHICH WOULD PROBABLY BE ADEQUATE. PROBLEMATIC SHEAR VALUES WILL BE LESS OF A CHALLENGE TO ATTAIN...BOTH DIRECTIONAL AND SPEED SHEAR. RUNNING THE NUMBERS THROUGH OUR LOCAL ANALOG TOOL BRINGS UP CASES WITH FLASH FLOODING BUT ALSO SPORADIC DAMAGING WINDS AND IN ONCE CASE EVEN AN ISOLATED TORNADO. THIS SEEMS REASONABLE GIVEN THE 0-1KM SHEAR AND HELICITY VALUES. SPC INCLUDES ALMOST ALL OF NEPA IN SLIGHT RISK OF SEVERE...WITH MARGINAL RISK REACHING JUST PAST PA/NY BORDER. HAIL WILL PROBABLY NOT BE AN ISSUE BECAUSE OF WARM CLOUD DEPTH...BUT DAMAGING WINDS AND EVEN ISOLATED TORNADOES CANNOT BE RULED OUT. THOUGH THERE WILL BE RAIN NORTH OF THE TWIN TIERS...CONDITIONS WILL GENERALLY BE TOO STABLE IN THE LOW LEVELS /TEMPERATURES MAINLY LOW 70S/ TO SUPPORT ANYTHING MORE THAN ISOLATED ELEVATED THUNDERSTORMS. FORECAST WAS ADJUSTED TO HAVE RAIN WILL LINGER A WAYS INTO THE EVENING...A BIT LONGER THAN PREVIOUSLY EXPECTED...BECAUSE UPPER JET SUPPORT LASTING INTO THE NIGHT. THE SYSTEM WILL EXIT OVERNIGHT THOUGH...LEAVING AREAS OF FOG AND LOW CLOUDS IN ITS WAKE. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... 430 AM UPDATE... SURFACE HIGH PRESSURE WILL TAKE OVER FOR THE SHORT TERM PERIOD...BRINGING WELCOME DRY WEATHER AND A GOOD AMOUNT OF SUNSHINE FRIDAY-SATURDAY. HIGHS UPPER 70S-LOW 80S...AND DEWPOINTS IN MID 50S TO NEAR 60...WILL FEEL VERY COMFORTABLE. HOWEVER...MAINLY CLEAR SKY AND LIGHT TO CALM WIND...ALONG WITH MOISTURE FROM PRIOR RAINFALL...WILL MAKE VALLEY FOG FORMATION LIKELY DURING THE PREDAWN HOURS OF SATURDAY MORNING AND ONLY TO A SLIGHT LESSER DEGREE SUNDAY MORNING. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... 210 AM UPDATE... A LONG WAVE RIDGE OVER CENTRAL CANADA WILL SLOPE DOWN TOWARD AN ATLANTIC TROF THIS PERIOD, WITH WEAK WAVES RIDING DOWN THE RIDGE INTO NY AND PA. THIS WILL KEEP THE THREAT FOR A SHOWER OR THUNDERSTORM IN THE FORECAST EACH PERIOD. THE ECMWF FORECASTS AN UL CLOSED LOW TO BREAK OFF FROM THE FLOW AT THE END OF THE WEEKEND, WITH A WEAK TROF DIPPING SOUTH ACROSS THE GREAT LAKES. THIS WILL INCREASE THE CHANCE FOR PRECIPITATION MONDAY AND TUESDAY. 3 PM UPDATE... OUR REGION WILL REMAIN INFLUENCED BY NORTHERN STREAM JET ENERGY THROUGH THIS PERIOD AS SEVERAL GLOBAL MODELS SUGGEST THE CARVING OUT OF YET ANOTHER BROAD TROF ACROSS THE NORTHEASTERN CONUS...AND POSSIBLY A CLOSED 500 MB LOW OVER THE UPPER LAKES BY MON-TUES. PLENTY OF UNCERTAINTY AMONGST THE BIG THREE (GFS/ECMWF/GGEM)...BUT THE OVERALL PATTERN STILL LOOKS TO AGAIN BECOME ACTIVE...UNSETTLED AND COOLER THAN NORMAL. MOST OF THE DAY SUNDAY SHOULD ESCAPE RAIN FREE UNTIL TOWARD EVENING WHEN SOME WEAK CONVECTIVE ACTIVITY COULD DRIFT IN ON A NORTHERN STREAM IMPULSE. AFTER THAT...AT LEAST THE GFS/ECMWF SUGGEST A CHANCE FOR SHOWERS/TSTMS ON MONDAY AND TUESDAY WITH AN APPROACHING FRONTAL SYSTEM. MODERATE POPS IN THE FORECAST. && .AVIATION /14Z THURSDAY THROUGH MONDAY/... RAIN AND THUNDERSTORMS WILL OVERSPREAD THE TERMINALS LATE THIS AFTERNOON AHEAD OF A STRONG FRONTAL SYSTEM. SOME OF THE STORMS WILL PRODUCE TORRENTIRAL DOWNPOURS AND STRONG WINDS, LOWERING VISIBILITIES AND CEILINGS INTO MVFR TERRITORY. BRIEF IFR IS EXPECTED, BUT THE DURATION WILL BE TOO SHORT TO JUSTIFY A TEMPO GROUP. THE BEST CHANCE FOR HEAVY RAIN WILL BE BETWEEN 19Z THURSDAY AND 00Z FRIDAY. WINDS WILL GENERALLY BE LIGHT AND VARIABLE, EXCEPT IN THUNDERSTORMS. .OUTLOOK... THU AFTRN THROUGH EARLY FRI...RESTRICTIONS POSSIBLE IN SCT SHRA/TSRA THU...ESPECIALLY CENTRAL TO SOUTHERN TERMINALS...FOLLOWED BY POSSIBLE LOW CLOUDS-FOG EARLY FRIDAY MORNING. MID MORNING FRI THROUGH SUN...VFR. MON...VFR WITH POSSIBLE MVFR SHRA/TSRA. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...FLASH FLOOD WATCH FROM 5 PM EDT THIS AFTERNOON THROUGH LATE TONIGHT FOR PAZ040-048-072. FLASH FLOOD WATCH FROM 1 PM EDT THIS AFTERNOON THROUGH THIS EVENING FOR PAZ038-039-043-044-047. NY...FLASH FLOOD WATCH FROM 5 PM EDT THIS AFTERNOON THROUGH LATE TONIGHT FOR NYZ046-057-062. FLASH FLOOD WATCH FROM 1 PM EDT THIS AFTERNOON THROUGH THIS EVENING FOR NYZ022>025-044-045-055-056. && $$ SYNOPSIS...DJN/MDP NEAR TERM...DJN/MDP SHORT TERM...MDP LONG TERM...ABS/DJP/JAB AVIATION...DJP
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
707 AM EDT THU JUL 9 2015 .SYNOPSIS... THE HEAT WILL BUILD AS BERMUDA HIGH PRESSURE REMAINS NEAR THE CAROLINAS THROUGH FRIDAY. A WEAK COLD FRONT WILL STALL ACROSS THE AREA DURING THE WEEKEND AND THEN DISSIPATE. A BETTER FLOW OF MOISTURE SHOULD BE LIFTED NORTH FROM THE CARIBBEAN SEA BY THE BERMUDA HIGH NEXT WEEK...RESULTING IN A GREATER COVERAGE OF SHOWERS AND THUNDERSTORMS. && .NEAR TERM /THROUGH TONIGHT/... AS OF 700 AM THURSDAY...CONSIDERABLE CONVECTIVE HIGH CLOUD DEBRIS LIES ACROSS THE FORECAST AREA...BUT THESE CLOUDS ARE EXPECTED TO SLOWLY DISSIPATE/THIN AS THE SUN RISES FURTHER ABOVE THE HORIZON THIS MORNING. THE HIGH RESOLUTION HRRR MODEL DOES SHOW SOME SHOWERS DEVELOPING ACROSS PORTIONS OF THE AREA THIS MORNING IN ASSOCIATION WITH A RESIDUAL OUTFLOW BOUNDARY FROM CONVECTION LAST NIGHT AND THE SOUTHERN END OF A MID-LEVEL SHORTWAVE TROUGH MOVING OFFSHORE. AT THIS TIME...WILL NOT STRAY FROM PREVIOUS THINKING GIVEN THE OVERALL ENVIRONMENT MAY JUST BE A LITTLE TOO HOSTILE. IT WILL BE A HOT DAY WITH MODEST HUMIDITY LEVELS. THIS WILL BRING THE HEAT INDEX UP TO 100 TO 104 DEGREES MIDDAY AND THIS AFTERNOON. A FEW INLAND SPOTS MAY BRIEFLY TOUCH 105 DEGREES. DO NOT EXPECT A SIGNIFICANT GEOGRAPHIC AREA WILL HIT 105 DEGREES FOR TWO HOURS OR MORE AS AFTERNOON DEWPOINTS ARE EXPECTED TO CREEP LOWER AS DRY AIR ALOFT MIXES TO THE SURFACE AS STRONG HEATING ENSUES. THUS...DO NOT PLAN ON ISSUING A HEAT ADVISORY. HIGH THIS AFTERNOON WILL BE IN THE MID AND UPPER 90S. THE SEABREEZE WILL BE PINNED TO THE COAST GIVEN THE WESTERLY FLOW. THIS WILL KEEP HIGHS AT THE BEACHES AND IMMEDIATE COAST IN THE LOWER 90S. TEMPS THIS EVE WILL BE WARM WITH LOWS NOT DROPPING TO 80 DEGREES UNTIL AROUND MIDNIGHT. LOWS WILL BE IN THE MID AND UPPER 70S...80 DEGREES OR SO AT THE BEACHES. BERMUDA HIGH PRESSURE WILL CONTINUE TO HOLD ITS POSITION ACROSS THE EASTERN CAROLINAS AS HEAT RIDGE ALOFT STRENGTHENS FURTHER. TEMPS AT 850 MB WILL REACH AROUND 21 DEG C TODAY...ABOUT A DEGREE HIGHER THAN ON WED. THE THERMAL TROUGH SHOULD AGAIN BE A PROMINENT FEATURE AS WILL THE SEABREEZE. THESE STRENGTHENING BOUNDARIES WILL SERVE TO INCREASE WIND SPEEDS THIS AFTERNOON AND EARLY EVE. WINDS WILL BE FROM THE SW OR WSW AT 10 TO 20 MPH WITH GUSTS NEAR 25 MPH AT THE BEACHES. MIXED LAYER CAPE VALUES WILL PEAK AROUND 2000 J/KG DURING THE TIME OF PEAK HEATING. GIVEN THE INSTABILITY AND THE AFOREMENTIONED MESOSCALE BOUNDARIES AND PERHAPS SOME RESIDUAL OUTFLOW FROM THE CONVECTION WHICH DISSIPATED ACROSS PORTIONS OF THE AREA LAST NIGHT...IT CERTAINLY WOULD NOT BE A STRETCH FOR ISOLATED SHOWERS AND THUNDERSTORMS TO DEVELOP. HOWEVER...WORKING AGAINST THE DEVELOPMENT OF CONVECTION TODAY IS NO UPPER LEVEL SUPPORT...WARM AIR ALOFT... STRONG SUBSIDENCE...A SIGNIFICANT AMOUNT OF DRY AIR IN THE COLUMN AND PARTICULARLY IN THE MID LEVELS...AND A WESTERLY FLOW IN THE LOWEST 25 KFT. THUS...AT THIS TIME...HAVE OPTED NOT TO INCLUDE SHOWERS AND THUNDERSTORMS IN THE FORECAST...ALTHOUGH AGAIN ONE OR TWO CAN NOT BE RULED OUT TODAY AND MAINLY DURING THE TIME OF PEAK HEATING. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 300 AM THURSDAY...ANOTHER VERY HOT DAY FRIDAY AS THE MID LEVEL RIDGE HANGS ON. EXPECT TEMPERATURES TO NEAR 100 INLAND AND THE UPPER 90S ALONG THE COAST. THE SLIGHTLY LOWER DEWPOINTS MIXING DOWN DURING MAX HEATING WILL PROBABLY KEEP AN OFFICIAL HEAT ADVISORY FROM BEING ISSUED. THERE COULD CERTAINLY BE A SMATTERING OF 105 VALUES BUT THE LONGEVITY SHOULD BE LIMITED. A SLOW DECREASE IN 850MB TEMPERATURES COMMENCES FRIDAY NIGHT THROUGH THE DAY SATURDAY AS A WEAK BOUNDARY CRAWLS SLOWLY SOUTH. THE EFFECTS WILL BE GRADUAL BUT OVERALL THIS SHOULD SHAVE 3-4 DEGREES OFF HIGH TEMPERATURES FOR SATURDAY WHEN COMPARED TO FRIDAY`S. THERE IS SOME SIGNALS OF CONVECTION WITH THIS BOUNDARY AND HAVE MAINTAINED THE SLIGHT CHANCE POPS FOCUSED ON PRIMARILY THE NORTHEAST && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 300 AM THURSDAY...A SUBTLE NORTHWEST FLOW WILL PREVAIL EARLY IN THE PERIOD AS A RETREATING MID LEVEL RIDGE MAKES ATTEMPTS TO BUILD BACK TO THE EAST. MORE SIGNIFICANT TROUGHING WILL DEVELOP TUESDAY THROUGH THURSDAY WEAKENING THE RIDGE AND SUPPRESSING IT FURTHER TO THE SOUTH AND EAST. SURFACE FEATURES ARE WHAT YOU WOULD EXPECT FOR THE MIDDLE PART OF JULY. THE PIEDMONT TROUGH AND A SERIES OF FADING FRONTS ESPECIALLY LATE MAKING A FUTILE PUSH INTO BERMUDA HIGH PRESSURE. THIS SERIES OF EVENTS WILL KEEP THE DAYS BEYOND MONDAY FAIRLY UNSETTLED. WE HAVE CHANCE TO GOOD CHANCE POPS EACH DAY. TEMPERATURES REMAIN A LITTLE ABOVE NORMAL EACH DAY AND MORESO AT NIGHT. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... AS OF 12Z...MAINLY SCT MID/BROKEN HIGH CLOUDS ARE OCCURRING THIS MORNING...DENSEST AT THE COASTAL TERMINALS. WINDS ARE SW-W 5 TO 10 KT. VFR EXPECTED ALL TERMINALS THIS TAF VALID PERIOD. WINDS WILL BE SW- W...EXCEPT AT THE COASTAL TERMINALS THIS AFTERNOON INTO EARLY EVENING. THE SEA BREEZE BOUNDARY WILL MOVE ONSHORE TODAY...BUT WITH W WINDS ALOFT THE BOUNDARYS INLAND PROGRESS WILL BE IMPEDED. THERE IS LOW CONFIDENCE AS TO THE TIMING OF THE SEA BREEZE PASSAGE IN COASTAL TAFS. ONCE THE BOUNDARY MOVES INLAND...LAND/SEA TEMPERATURE DIFFERENCES COULD PRODUCE WIND SPEEDS OF 15 TO 20 KT FROM THE SSW. ONLY ISOLATED AIRMASS SHOWERS/THUNDERSTORMS EXPECTED TODAY THUS WILL OMIT MENTION FROM TAFS. PROBABLY THE BEST AREA FOR SOME DEVELOPMENT WILL BE NW OF KCRE WHERE THE SEA BREEZE BOUNDARY AND AN OLD OUTFLOW BOUNDARY WILL INTERACT. THIS IDEA IS SUPPORTED BY SOME HIGH RESOLUTION MODELS. IF ACTIVITY DEVELOPS IT COULD MOVE TOWARDS KCRE LATE MORNING/EARLY AFTERNOON...BUT CONFIDENCE IS LOW SINCE ITS AN OVERALL HOSTILE ENVIRONMENT FOR ANY DEVELOPMENT. OTHERWISE WINDS DECREASE THIS EVENING WITH SCT LO/MID CLOUDS AND BROKEN HIGH CLOUDS CONTINUING OVERNIGHT. EXTENDED OUTLOOK...CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY...WITH BRIEF PERIODS OF MVFR/IFR POSSIBLE. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 700 AM THURSDAY...THE BERMUDA RIDGE WILL REMAIN IN PLACE. THE SHARPENING PIEDMONT TROUGH AND SEABREEZE WILL HELP TO TIGHTEN THE PRESSURE GRADIENT ACROSS THE WATERS. TONIGHT...LOW LEVEL JETTING WILL AGAIN HELP TO KEEP WIND SPEEDS ELEVATED. THE STRONGEST WINDS ARE EXPECTED TO DEVELOP THIS AFTERNOON AND TO CONTINUE TONIGHT...15 TO 20 KT. THE DIRECTION WILL BE SW. SEAS WILL BE 3 TO 4 FT THROUGHOUT. AN 8 TO 10 SECOND SE GROUND SWELL WILL PERSIST. SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 300 AM THURSDAY...ESSENTIALLY SUMMERTIME CONDITIONS FOR THE COASTAL WATERS FRIDAY THROUGH EARLY SATURDAY. SOUTHWEST WINDS OF 10- 15 KNOTS...HIGHER FRIDAY NIGHT WITH SEAS OF 2-4 FEET. A WEAK BOUNDARY ATTEMPTS TO TURN THE WINDS TO WEST AND EVEN NORTH EARLY SATURDAY AND AGAIN OVERNIGHT SATURDAY INTO SUNDAY MORNING. THE BOUNDARY IS SO WEAK HOWEVER THAT THE SOUTHWEST FLOW WILL PREVAIL FOR THE MOST PART. LONG TERM /SUNDAY THROUGH MONDAY/... AS OF 300 AM THURSDAY...WEAK LOW PRESSURE INLAND AND HIGH PRESSURE...ATTEMPTING TO PUSH DOWN FROM THE APPALACHIANS WILL KEEP A LIGHT NORTHERLY COMPONENT TO THE WINDS SUNDAY. BY MONDAY THESE FEATURES HAVE FADED AND THE SOUTHEAST FLOW DEVELOPS ONCE AGAIN. NO SIGNIFICANT SWELL TO DRIVE SEAS BEYOND THE TOKEN VALUES DRIVEN BY THE WINDS...2-4 FEET. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...RJD SHORT TERM...SHK LONG TERM...SHK AVIATION...MRR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
936 PM CDT FRI JUL 10 2015 .UPDATE... ISSUED AT 933 PM CDT FRI JUL 10 2015 NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE AS ANY CONVECTION FOR THE REMAINDER OF THE NIGHT WILL BE ISOLATED AT BEST AS THE LOW LEVEL JET INCREASES UNDER SOUTHWEST FLOW ALOFT. THIS IS SUPPORTED BY THE 00 UTC NAM AND 00-01 UTC HRRR ITERATIONS. UPDATE ISSUED AT 733 PM CDT FRI JUL 10 2015 WHILE ISOLATED CELLS HAVE INITIATED ACROSS SOUTH CENTRAL NORTH DAKOTA THIS EVENING...WEAK LAPSE RATES AND SHEAR HAVE LEAD TO VERY QUICK DISSIPATION OF THESE SHOWERS/STORMS. THE HRRR THUS FAR THIS EVENING FROM RUN TO RUN HAS OVER DEVELOPED CONVECTION ACROSS THE DAKOTAS GIVEN THE HIGH CAPE/LOW CIN ENVIRONMENT. THUS...FAVORED THE 18 UTC NAM AND 15 UTC SREF WHOSE QPF FIELDS ARE CLOSET TO RADAR TRENDS THROUGH 00 UTC. DO EXPECT AN ISOLATED THUNDERSTORM THREAT TO CONTINUE THROUGH THE NIGHT AS THE LOW LEVEL JET INCREASES UNDER SOUTHWEST FLOW ALOFT. HOWEVER...CONTINUED WEAK SHEAR PRECLUDES A SEVERE THREAT. UPDATE ISSUED AT 457 PM CDT FRI JUL 10 2015 BASED ON RADAR TRENDS THROUGH 2150 UTC OF ISOLATED TO SCATTERED THUNDERSTORMS DEVELOPING ACROSS NORTH CENTRAL SOUTH DAKOTA AND A TIME LAGGED ENSEMBLE OF THE 18-20 UTC HRRR RUNS...INTRODUCED POPS TO THE FAR SOUTH CENTRAL AND JAMES RIVER VALLEY FOR LATE THIS AFTERNOON AND EARLY EVENING. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 224 PM CDT FRI JUL 10 2015 CURRENT SURFACE ANALYSIS PLACES LOW OVER CENTRAL MONTANA WITH TROUGH OVER SOUTHEAST MONTANA INTO NORTHEAST WYOMING. UPPER LEVEL ANALYSIS PLACES BROAD UPPER LOW NEAR THE NORTHERN GREAT BASIN WITH A VARIETY OF WEAK VORTICES WORKING AROUND THE SYSTEM. OVER OUR AREA...SHORT WAVE LIFTING THROUGH SOUTHWESTERLY FLOW IS STARTING TO PRODUCE SOME LIGHT CONVECTION OVER SOUTHEAST MONTANA INTO NORTHERN WYOMING. FOR THE REST OF THIS AFTERNOON INTO TONIGHT...AFOREMENTIONED SHORT WAVE WILL CONTINUE TO LIFT TOWARDS THE AREA...WITH SOME THUNDERSTORMS POSSIBLY DEVELOPING TOWARDS LATE AFTERNOON OVER THE SOUTHWEST. WAVE WILL CONTINUE TO LIFT OVER THE AREA...FOLLOWED BY A VARIETY OF ADDITIONAL WEAK SHORT WAVES...THROUGH TONIGHT. MODEST INSTABILITY REMAINS IN PLACE BUT LITTLE TO NO SHEAR IS AVAILABLE SO EXPECT STORMS OVERALL TO REMAIN TAME AND RATHER PULSE. ON SATURDAY...SURFACE LOW LIFTS THROUGH NORTHEAST MONTANA DRAWING PLENTY OF MOISTURE AHEAD OF IT OVER MUCH OF NORTH DAKOTA. THE EXCEPTION WILL BE OVER THE SOUTHWEST WHERE A DRYLINE WILL SETUP WITH FALLING DEWPOINTS AND SOUTHWESTERLY WINDS. TIMING OF CONVECTION DEVELOPING WILL BE TRICKY GIVEN THE VARIETY OF SHORT WAVES LIFTING THROUGH THE AREA. INSTABILITY INCREASES QUITE A BIT WITH THE INCREASING MOISTURE WHICH WILL COMBINE WITH MODEST SHEAR TO BRING A MARGINAL SEVERE THREAT OVER CENTRAL INTO NORTHWESTERN NORTH DAKOTA. LARGE HAIL WILL BE THE MAIN THREAT. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 224 PM CDT FRI JUL 10 2015 THE LONG TERM WILL REMAIN ACTIVE SATURDAY THROUGH THE NEXT WEEK. SOUTHWEST FLOW ALOFT OVER THE WESTERN US WILL REMAIN OVER THE NEXT WEEK. THIS WILL PUT NORTH DAKOTA IN A FAVORABLE POSITION TO RECEIVE MANY UPPER LEVEL SHORT WAVES. ONE SUCH UPPER LOW IS EXPECTED TO REACH THE NORTHERN PLAINS SATURDAY. WARM...MOIST AIR WILL SURGE NORTH AHEAD OF THIS WAVE. A RATHER WARM AND MUGGY SATURDAY/SUNDAY IS EXPECTED. MODELS ARE INDICATING VERY HIGH CAPE VALUES BUT LITTLE TO NO SHEAR. WITH VERY HIGH MOISTURE CONTENT THROUGHOUT THE ATMOSPHERE...VERY HEAVY RAIN IS POSSIBLE WITH ANY THUNDERSTORMS THAT DEVELOP. THE LATEST SPC SEVERE OUTLOOKS PLACE A MARGINAL THREAT FOR SATURDAY. MOST OF THE THUNDERSTORM ACTIVITY IS EXPECTED NORTH SUNDAY AND MONDAY. BY WEDNEDAY AND THURSDAY ANOTHER WAVE IS EXPECTED TO MOVE THROUGH AS A UPPER LEVEL RIDGE ACROSS THE SOUTH CENTRAL CONUS MOVES EAST. AT THIS TIME THE GFS/ECMWF INDICATE SCATTERED THUNDERSTORMS ARE POSSIBLE ACROSS ALL OF WESTERN AND CENTRAL NORTH DAKOTA AS THE TRACK OF THIS LOW SHOULD BE FURTHER SOUTH THAN THIS WEEKEND`S. TEMPERATURES SHOULD GENERALLY RANGE FROM THE MID 80S TO LOW 90S THROUGH THE NEXT WEEK. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 933 PM CDT FRI JUL 10 2015 ISOLATED THUNDERSTORMS ARE POSSIBLE ACROSS WESTERN AND CENTRAL NORTH DAKOTA THIS EVENING INTO THURSDAY. ANY DIRECT IMPACT TO ONE OF THE TERMINALS IS HIGHLY UNCERTAIN DUE TO A SMALL COVERAGE OF STORMS. VFR CONDITIONS EXPECTED OUTSIDE OF THUNDERSTORMS. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD SHORT TERM...JJS LONG TERM...AJ AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
740 PM CDT FRI JUL 10 2015 .UPDATE... ISSUED AT 733 PM CDT FRI JUL 10 2015 WHILE ISOLATED CELLS HAVE INITIATED ACROSS SOUTH CENTRAL NORTH DAKOTA THIS EVENING...WEAK LAPSE RATES AND SHEAR HAVE LEAD TO VERY QUICK DISSIPATION OF THESE SHOWERS/STORMS. THE HRRR THUS FAR THIS EVENING FROM RUN TO RUN HAS OVER DEVELOPED CONVECTION ACROSS THE DAKOTAS GIVEN THE HIGH CAPE/LOW CIN ENVIRONMENT. THUS...FAVORED THE 18 UTC NAM AND 15 UTC SREF WHOSE QPF FIELDS ARE CLOSET TO RADAR TRENDS THROUGH 00 UTC. DO EXPECT AN ISOLATED THUNDERSTORM THREAT TO CONTINUE THROUGH THE NIGHT AS THE LOW LEVEL JET INCREASES UNDER SOUTHWEST FLOW ALOFT. HOWEVER...CONTINUED WEAK SHEAR PRECLUDES A SEVERE THREAT. UPDATE ISSUED AT 457 PM CDT FRI JUL 10 2015 BASED ON RADAR TRENDS THROUGH 2150 UTC OF ISOLATED TO SCATTERED THUNDERSTORMS DEVELOPING ACROSS NORTH CENTRAL SOUTH DAKOTA AND A TIME LAGGED ENSEMBLE OF THE 18-20 UTC HRRR RUNS...INTRODUCED POPS TO THE FAR SOUTH CENTRAL AND JAMES RIVER VALLEY FOR LATE THIS AFTERNOON AND EARLY EVENING. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 224 PM CDT FRI JUL 10 2015 CURRENT SURFACE ANALYSIS PLACES LOW OVER CENTRAL MONTANA WITH TROUGH OVER SOUTHEAST MONTANA INTO NORTHEAST WYOMING. UPPER LEVEL ANALYSIS PLACES BROAD UPPER LOW NEAR THE NORTHERN GREAT BASIN WITH A VARIETY OF WEAK VORTICES WORKING AROUND THE SYSTEM. OVER OUR AREA...SHORT WAVE LIFTING THROUGH SOUTHWESTERLY FLOW IS STARTING TO PRODUCE SOME LIGHT CONVECTION OVER SOUTHEAST MONTANA INTO NORTHERN WYOMING. FOR THE REST OF THIS AFTERNOON INTO TONIGHT...AFOREMENTIONED SHORT WAVE WILL CONTINUE TO LIFT TOWARDS THE AREA...WITH SOME THUNDERSTORMS POSSIBLY DEVELOPING TOWARDS LATE AFTERNOON OVER THE SOUTHWEST. WAVE WILL CONTINUE TO LIFT OVER THE AREA...FOLLOWED BY A VARIETY OF ADDITIONAL WEAK SHORT WAVES...THROUGH TONIGHT. MODEST INSTABILITY REMAINS IN PLACE BUT LITTLE TO NO SHEAR IS AVAILABLE SO EXPECT STORMS OVERALL TO REMAIN TAME AND RATHER PULSE. ON SATURDAY...SURFACE LOW LIFTS THROUGH NORTHEAST MONTANA DRAWING PLENTY OF MOISTURE AHEAD OF IT OVER MUCH OF NORTH DAKOTA. THE EXCEPTION WILL BE OVER THE SOUTHWEST WHERE A DRYLINE WILL SETUP WITH FALLING DEWPOINTS AND SOUTHWESTERLY WINDS. TIMING OF CONVECTION DEVELOPING WILL BE TRICKY GIVEN THE VARIETY OF SHORT WAVES LIFTING THROUGH THE AREA. INSTABILITY INCREASES QUITE A BIT WITH THE INCREASING MOISTURE WHICH WILL COMBINE WITH MODEST SHEAR TO BRING A MARGINAL SEVERE THREAT OVER CENTRAL INTO NORTHWESTERN NORTH DAKOTA. LARGE HAIL WILL BE THE MAIN THREAT. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 224 PM CDT FRI JUL 10 2015 THE LONG TERM WILL REMAIN ACTIVE SATURDAY THROUGH THE NEXT WEEK. SOUTHWEST FLOW ALOFT OVER THE WESTERN US WILL REMAIN OVER THE NEXT WEEK. THIS WILL PUT NORTH DAKOTA IN A FAVORABLE POSITION TO RECEIVE MANY UPPER LEVEL SHORT WAVES. ONE SUCH UPPER LOW IS EXPECTED TO REACH THE NORTHERN PLAINS SATURDAY. WARM...MOIST AIR WILL SURGE NORTH AHEAD OF THIS WAVE. A RATHER WARM AND MUGGY SATURDAY/SUNDAY IS EXPECTED. MODELS ARE INDICATING VERY HIGH CAPE VALUES BUT LITTLE TO NO SHEAR. WITH VERY HIGH MOISTURE CONTENT THROUGHOUT THE ATMOSPHERE...VERY HEAVY RAIN IS POSSIBLE WITH ANY THUNDERSTORMS THAT DEVELOP. THE LATEST SPC SEVERE OUTLOOKS PLACE A MARGINAL THREAT FOR SATURDAY. MOST OF THE THUNDERSTORM ACTIVITY IS EXPECTED NORTH SUNDAY AND MONDAY. BY WEDNEDAY AND THURSDAY ANOTHER WAVE IS EXPECTED TO MOVE THROUGH AS A UPPER LEVEL RIDGE ACROSS THE SOUTH CENTRAL CONUS MOVES EAST. AT THIS TIME THE GFS/ECMWF INDICATE SCATTERED THUNDERSTORMS ARE POSSIBLE ACROSS ALL OF WESTERN AND CENTRAL NORTH DAKOTA AS THE TRACK OF THIS LOW SHOULD BE FURTHER SOUTH THAN THIS WEEKEND`S. TEMPERATURES SHOULD GENERALLY RANGE FROM THE MID 80S TO LOW 90S THROUGH THE NEXT WEEK. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 733 PM CDT FRI JUL 10 2015 ISOLATED THUNDERSTORMS ARE POSSIBLE ACROSS WESTERN AND CENTRAL NORTH DAKOTA THIS EVENING INTO THURSDAY. ANY DIRECT IMPACT TO ONE OF THE TERMINALS IS HIGHLY UNCERTAIN DUE TO A SMALL COVERAGE OF STORMS. VFR CONDITIONS EXPECTED OUTSIDE OF THUNDERSTORMS. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD SHORT TERM...JJS LONG TERM...AJ AVIATION...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1143 PM CDT WED JUL 8 2015 .UPDATE... ISSUED AT 1140 PM CDT WED JUL 8 2015 T-STORMS IN NRN LAKE OF THE WOODS REGION DISSIPATING TO SHOWERS NOW AND WILL HAVE SCT -SHRA IN SMALL AERA IN LOW REGION TIL 07Z. O/W REMAINING PATCHY CLOUDS IN NORTH CENTRAL MN WILL MOVE OUT. CLEAR ELSEWHERE. WILL MAINTAIN SOME PATCHY FOG AS HRRR DOES INDICATE PATCHY LOW VSBY IN SPOTS. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 250 PM CDT WED JUL 8 2015 THE MAIN CHALLENGE WILL BE CONVECTION THIS AFTERNOON INTO EARLY EVENING...THEN TEMPS. MODELS ARE IN GOOD OVERALL AGREEMENT...WITH THE GFS HAVING A GOOD HANDLE ON INSTABILITY. FOR LATE THIS AFTERNOON AND TONIGHT...THERE COULD BE SOME SCATTERED CONVECTION THAT SHOULD WEAKEN QUICKLY AROUND SUNSET. CAN/T RULE OUT A STRONG STORM OR TWO...BUT IT APPEARS THAT INSTABILITY MAY NOT BE HIGH ENOUGH FOR AN ORGANIZED SEVERE THREAT WITH LOW CONVECTIVE TEMPS. ANY CONVECTION WILL BE GONE AROUND 3Z...AND HAVE TRENDED POPS THIS WAY. PATCHY FOG CAN/T BE RULED OUT LATER TONIGHT...AND BUFKIT INDICATES FOG IS FAVORED IN ALL BUT THE NORTHWEST. WE WILL ADD SOME PATCHY FOG ALL AREAS EXCEPT THE DVL BASIN 8-13Z. FOR THU....EXPECT A DRY AND WARM DAY WITH MID LEVEL TEMPS WARMING AND A BUILDING SHORTWAVE RIDGE. THERE SHOULD BE PLENTIFUL SUNSHINE AS WELL...AND A NICE SUMMER DAY IS EXPECTED. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 250 PM CDT WED JUL 8 2015 ON FRIDAY...EVEN WARMER AIR ALOFT WILL MOVE OVER THE REGION. THE ONLY THING THAT COULD LIMIT TEMPS IS IF SMOKE RETURNS TO THE REGION. THEREFORE...HAVE KEPT HIGHS IN THE MID 80S FOR THE MOST PART...BUT IF THERE IS NO SMOKE IT COULD BE AROUND 90. FOR SAT...THE THREAT FOR SHOWERS AND STORMS WILL SLOWLY SPREAD FROM WEST TO EAST. THE HUMIDITY WILL INCREASE WITH PWATS RISING OVER 1.5 INCHES...ALONG WITH PLENTY OF INSTABILITY. ANY CONVECTION SHOULD REMAIN ELEVATED THOUGH WITH NO REAL SFC BOUNDARY...BUT WILL CONTINUE WITH THE LOW POPS MAINLY VALLEY WEST BY SAT AFTERNOON. IT WILL BE WARM AND IF THERE IS SMOKE AIR QUALITY COULD BECOME AN ISSUE ONCE AGAIN. .EXTENDED (SATURDAY NIGHT-WEDNESDAY)...NOT MUCH CHANGE FROM PREVIOUS THINKING REGARDING THIS PERIOD. SUNDAY SHOWS THE STRONGEST SIGNAL FOR THUNDERSTORM POTENTIAL WITH A SHORTWAVE IN THE AREA...ALTHOUGH DEEP LAYER SHEAR APPEARS RELATIVELY WEAK AND UNSURE HOW WIDESPREAD/STRONG STORMS WILL BE. THE REMAINDER OF THE PERIOD WILL BE WITHIN UPPER LEVEL RIDGE TRANSITIONING TO SW FLOW ALOFT. ALTHOUGH THE MODEL BLEND SOLUTION GIVES THUNDER CHANCES EVERY DAY...BEST CHANCES PROBABLY MORE TOWARD MID-WEEK. TEMPERATURES WILL BE SLIGHTLY ABOVE NORMAL VALUES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1140 PM CDT WED JUL 8 2015 PATCHY GROUND FOG PSBL EARLY THIS MORNING AROUND DAWN...BUT CONFIDENCE IN WHERE AND VSBY KEEPS ME FROM MENTIONING FOG AT ANY TAF SITE ATTM. OTHERWISE VFR THRU THURSDAY WITH CLEAR SKY WITH INCREASING SOUTH-SOUTHWEST WIND THURSDAY AFTN. GUST TO NR 20 KTS PSBL WEST OF THE RRV THU AFTN. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...RIDDLE SHORT TERM...DK LONG TERM...TG/DK AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1031 PM EDT FRI JUL 10 2015 .SYNOPSIS... UNSETTLED AND WET PATTERN LINGERS INTO THE WEEKEND. A SERIES OF UPPER LEVEL DISTURBANCES WILL CROSS THE AREA UNDER NORTHWEST FLOW NEXT WEEK...KEEPING UNSETTLED CONDITIONS EACH DAY. && .NEAR TERM /THROUGH SATURDAY/... 1030 PM UPDATE... SEEING THE MCS/MCV TYPE SYS COMING TO FRUITION OVER SE OH AND NE KY OVER THE LAST HR. LAST FEW IR SATELLITE IMAGES BEAR THIS OUT ALONG WITH RADAR. 00Z NAM AND LAST FEW RUNS OF THE HRRR HAVE LATCHED ON TO THIS NOW THAT IT HAS DEVELOPED. AS SUCH...HAVE LEANED HEAVILY ON THESE MODELS FOR REMAINDER OF THE OVERNIGHT. THERE IS GROWING CONCERN OF A RENEWED FLASH FLOOD EVENT IN THE C LOWLANDS OVERNIGHT...OVER AREAS THAT HAVE BEEN HIT HARD THE PAST FEW DAYS. QPF AMOUNTS OF 1 TO 2 INCHES UNDER A SOMEWHAT NARROW BAND CAN BE EXPECTED ACROSS THE ROUTE 33 CORRIDOR AND INTO THE N MTNS. PREVIOUS DISCUSSION BELOW... UNSETTLED WEATHER CONTINUES...LIKE A BROKEN RECORD THAT WONT FALL OFF THE TURNTABLE. FRONTAL BOUNDARY ACROSS SOUTHERN HALF OF THE CWA AT 1730Z. HIGH PWS REMAIN ACROSS THE AREA...GENERALLY 1.6 TO 2 INCHES...ONCE AGAIN. UPPER SHORTWAVE PUSHING EAST OUT OF THE MIDWEST...IS HELPING TO GENERATE MORE SHOWERS AND THUNDERSTORMS. SOME WITH FLOODING RAINS. FRONTAL BOUNDARY WILL LIFT SLIGHTLY NORTH TODAY AS SHORTWAVE APPROACHES. SOME FLASH FLOODING HAS ALREADY BEEN REPORTED WITH STORMS THAT HAVE DEVELOPED...AND HAVE FLASH FLOOD WATCHES POSTED THROUGH SATURDAY MORNING. THESE MAY BE A LITTLE LONG IN DURATION...BUT WANTED TO ACCOUNT FOR THE DIFFERENCE IN MODEL TRENDS AND TIMING OVERNIGHT...AND WILL LIKELY BE DROPPED SOMETIME LATE TONIGHT. IN ADDITION...MCS ASSOCIATED WITH APPROACHING SHORTWAVE WILL AFFECT AT LEAST WESTERN ZONES THIS AFTERNOON. STILL SOME UNCERTAINTY AS TO HOW FAR EAST THE SEVERE THREAT WILL BE. HAVE A WATCH OUT FOR WESTERN/SOUTHERN ZONES UNTIL 4 PM. && .SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/... AN UPPER LEVEL RIDGE WILL BRING DRIER CONDITIONS TO THE AREA SATURDAY NIGHT INTO EARLY SUNDAY. THEN...MODELS BRING A SHORT WAVE AT H500 CROSSING THE AREA SUNDAY AFTERNOON THROUGH SUNDAY NIGHT. WITH SFC DEWPOINTS IN THE MID TO UPPER 60S...PWATS INCREASING TO AROUND 2 INCHES MODELS BRING A CONSIDERABLE AMOUNT OF QPF OVER THE AREA LATE SUNDAY INTO EARLY MONDAY. THEREFORE...INCREASE POPS TO TO HIGH CHANCE SUNDAY AND TO LIKELY SUNDAY NIGHT AND MONDAY. UNDER NORTHWEST FLOW ALOFT...ADDITIONAL UPPER LEVEL DISTURBANCES WILL KEEP UNSETTLED WEATHER THROUGH MONDAY NIGHT. ALTHOUGH THERE WILL BE A SLIGHT DECREASE IN MOISTURE WITH PWATS GOING BACK TO AROUND 1.5 INCHES MONDAY NIGHT. WITH THE WET SOIL CONDITIONS...LUSH VEGETATION...CLOUDS AND SHOWERS... TEMPERATURES WILL BE SEASONABLE BUT ALSO HUMID. THE POTENTIAL FOR FLOODING CONTINUES TO BE A CONCERN FOR THIS PERIOD. && .LONG TERM /TUESDAY THROUGH FRIDAY/... A SERIES OF UPPER LEVEL DISTURBANCES UNDER NORTHWEST FLOW ALOFT WILL CROSS THE AREA KEEPING THE PATTERN UNSETTLED THROUGH THE REMINDER OF THE WEEK WITH CHANCES FOR SHOWERS AND THUNDERSTORMS EACH DAY. ALLOWED CHANCE POPS ACROSS THE AREA DUE TO UNCERTAINTIES BY THE MODELS IN THE LONG PERIOD. THEREFORE...ALLOWED SLIGHT CHANCE POPS WEDNESDAY NIGHT ON. WITH THE GROUNDS ALREADY SATURATED...WILL HAVE TO CONTINUE MONITORING THE WEATHER CLOSELY EACH DAY DUE TO WATER CONCERNS. WENT WITH WPC THINKING WITH TEMPERATURES...SKY...AND POPS THROUGH THE PERIOD. && .AVIATION /03Z SATURDAY THROUGH WEDNESDAY/... 00Z SATURDAY THROUGH 00Z SUNDAY... SCT SHRA AND A FEW TSRA WILL BE THE RULE THRU 06Z UNTIL AN S/W TROF CAN CROSS. EXPECT GENERALLY MVFR CONDITIONS IN SHRA WITH LOCALIZED IFR IN THE HEAVIER SHRA. AFTER 09Z...THE ACTIVITY WILL SHIFT INTO THE MTNS BEFORE TAPERING OFF AROUND 12Z AS THE S/W TROF MOVES E OF THE AREA. ABSENT PRECIP...EXPECT MVFR CIGS/VSBY TO DEVELOP OVERNIGHT...WITH CIGS DROPPING INTO IFR IN PLACES LATE. THERE MAY ALSO BE SOME IFR OR WORSE VSBY AS WELL. ANY STRATUS OR FG WILL MIX OUT INTO BKN MVFR CU FOR A TIME MID MORNING BEFORE SCT OUT ALL TOGETHER OVER SE OH...NE KY...W WV. A BKN CU FIELD MAY LINGER FOR E TERMINALS BUT SHOULD REMAIN VFR. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY... FORECAST CONFIDENCE: LOW TONIGHT. ALTERNATE SCENARIOS: EXTENT OF MVFR/IFR CONDITIONS OVERNIGHT IN QUESTION. AFTER 00Z SUNDAY...IFR POSSIBLE IN THUNDERSTORMS SATURDAY...MAINLY ACROSS THE EAST. && WV...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR WVZ005>008- 013>018-024>030-033>039-046-047. OH...FLASH FLOOD WATCH UNTIL 8 AM EDT SATURDAY FOR OHZ087. KY...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR KYZ105. FLASH FLOOD WATCH UNTIL 8 AM EDT SATURDAY FOR KYZ101>103. VA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR VAZ003-004. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR WVZ005>008- 013>018-024>030-033>039-046-047. OH...FLASH FLOOD WATCH UNTIL 8 AM EDT SATURDAY FOR OHZ087. KY...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR KYZ105. FLASH FLOOD WATCH UNTIL 8 AM EDT SATURDAY FOR KYZ101>103. VA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR VAZ003-004. && $$ SYNOPSIS...ARJ/SL NEAR TERM...SL/30 SHORT TERM...ARJ LONG TERM...JB/ARJ AVIATION...30
AREA FORECAST DISCUSSION
NWS PENDLETON OR
250 PM PDT THU JUL 9 2015 .SHORT TERM...TONIGHT THROUGH SUNDAY...AN UPPER LOW OVER CALIFORNIA AND WESTERN NEVADA WILL OPEN INTO A TROUGH AND SWING NORTHEAST ACROSS THE REGION FRIDAY AND FRIDAY NIGHT. THUS WILL SEE PLENTY OF MOISTURE AND INSTABILITY TO SUPPORT VARYING AMOUNTS OF SHOWERS AND THUNDERSTORMS OVER THE AREA TONIGHT THROUGH FRIDAY NIGHT. PRECIP WITH THE STRONGER SHOWERS/STORMS COULD BE HEAVY, ESPECIALLY FROM THE OCHOCO-JOHN DAY HIGHLANDS NORTH TO THE BLUES AND WALLOWA COUNTY FRIDAY. HAVE ISSUED A FLASH FLOOD WATCH FOR THESE AREAS FOR THE PERIOD FRIDAY AFTERNOON AND EVENING. INCREASING WESTERLY FLOW WILL GRADUALLY END THE SHOWER/STORM THREAT OVER PORTIONS OF NORTH CENTRAL AND CENTRAL OREGON, AND THE COLUMBIA BASIN FRIDAY NIGHT INTO SATURDAY MORNING. THIS WESTERLY FLOW WILL KEEP MUCH OF THESE SAME AREAS DRY SATURDAY AFTERNOON AND EVENING, BUT ANOTHER WAVE WILL KEEP VARYING CHANCES OF SHOWERS AND/OR STORMS GOING ELSEWHERE. LOCALLY HEAVY RAIN MAY BE POSSIBLE SATURDAY AFTERNOON/EVENING OVER WALLOWA COUNTY. ANOTHER TROUGH APPROACHING THE PACNW SUNDAY WILL KEEP THE FLOW OVER THE AREA SOUTHWESTERLY. THUS VARYING CHANCES OF SHOWERS AND STORMS WILL CONTINUE OVER A GOOD PORTION OF THE AREA. HIGH TEMPS WILL COOL TO NEAR SEASONAL VALUES THIS WEEKEND. 90 .LONG TERM...SUNDAY NIGHT THROUGH THURSDAY NIGHT...THE CONSENSUS IN MODEL FORECAST GUIDANCE SHOWS A BROAD UPPER TROUGH OFFSHORE NEAR 127W SUNDAY NIGHT MOVING EAST, THUS GIVING A SOUTHWEST FLOW ALOFT OVR FORECAST AREA SUNDAY NIGHT, WHICH BRINGS MOISTURE INTO FORECAST AREA FOR A CHANCE OF SHOWERS AND A SLIGHT CHANCE OF NOCTURNAL THUNDERSTORMS OVER THE CENTRAL AND EASTERN MOUNTAINS OF OREGON, THE BLUE MOUNTAINS, AND THE EAST SLOPES OF THE CENTRAL AND SOUTHERN WASHINGTON CASCADES. THE AFOREMENTIONED TROUGH MOVES INLAND MONDAY MORNING AND THEN ACROSS FORECAST AREA MONDAY AFTERNOON THROUGH MONDAY NIGHT, WHICH WILL KEEP A CHANCE OF SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS MONDAY AFTERNOON AND MONDAY NIGHT. BY DAYBREAK ON TUESDAY, THE TROUGH AXIS WILL HAVE EXITED THE REGION RESULTING IN JUST A SLIGHT CHANCE OF SHOWERS AND MAYBE A STRAY THUNDERSTORM OVER THE ELKHORN AND WALLOWA MOUNTAINS THROUGH TUESDAY AFTERNOON. THE CHANCE FOR PRECIPITATION WINDS DOWN TUESDAY NIGHT DUE TO WESTERLY FLOW ALOFT PRODUCING SINKING MOTION EAST OF THE CASCADES THUS YIELDING DRY ND STABLE CONDITIONS, WHICH WILL PERSIST THROUGH THURSDAY WITH ONLY A SLIGHT CHANCE OF A SHOWER OR A THUNDERSTORM IN WALLOWA COUNTY THROUGH TUESDAY AFTERNOON. TUESDAY NIGHT THROUGH THURSDAY NIGHT THE INTERIOR PACIFIC NORTHWEST WILL BE IN A WESTERLY FLOW ALOFT, WHICH PRODUCES WESTERLY DOWN SLOPE WINDS EAST OF THE CASCADES RESULTING IN SINKING AIR WHICH RESULTS IN DRY AND STABLE CONDITIONS TUESDAY NIGHT AND WEDNESDAY. POLAN && .AVIATION...PREVIOUS DISCUSSION...18Z TAFS...SCT-BKN 110-150 KRDM AND KBDN TODAY. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS POSSIBLE AFTER 21Z FOR KRDM AND KBDN WITH BEST CHANCES FROM 21Z-04Z. OTHERWISE, FEW-SCT 150-200 AGL THIS MORNING INTO THIS AFTERNOON IN SOUTH CENTRAL AND SOUTHEAST WASHINGTON WITH INCREASING CLOUDS SPREADING NORTH INTO THESE AREAS BY LATE THIS AFTERNOON. SCT -SHRA AND ISOLD TSRA WILL SPREAD WEST INTO CENTRAL AND EAST CENTRAL OREGON THIS AFTERNOON AND WILL ALSO DEVELOP OVER THE OCHOCO AND ALDRICH MOUNTAINS THIS AFTERNOON IN CENTRAL OREGON AND OVER THE BLUE MOUNTAINS AND MAY MOVE TO THE VICINITY OF KDLS, KPDT AND KALW AFTER 01Z; HOWEVER, THE PROBABILITY FOR THESE TAF SITES TO GET VCTS IS TOO LOW TO INCLUDE IN TAFS. POLAN && .FIRE WEATHER...LAND MANAGEMENT AGENCIES SHOULD GET A SIGH OF RELIEF AS THE WEATHER TRANSITIONS FROM THE HOT, DRY AND UNSTABLE CONDITIONS OVER THE PAST TWO WEEKS TO MORE COOLER AND SHOWERY CONDITIONS OVER THE WEEKEND. THE NEXT 3-6 HOURS WILL BE THE TIME OF RED FLAG CONDITIONS AS THUNDERSTORMS ARE DEVELOPING OVER CENTRAL AND NORTHEAST OREGON AND SHOULD INCREASE IN COVERAGE. CLOUD COVER HAS LIMITED SOME OF THE SURFACE HEATING...AND THUNDERSTORMS ARE MAINLY ISOLATED AT THIS TIME. HOWEVER...THUNDERSTORMS THAT HAVE DEVELOPED IN DESCHUTES COUNTY PRODUCED ABOUT 60 STRIKES IN THE PAST 30 MINUTES. THE HRRR WAS SHOWING WEAK OUTFLOW BOUNDARIES THAT COULD ALSO RESULT IN RAPID FIRE SPREAD FOR NEW AND EXISTING FIRES. AS STATED IN THE SHORT TERM DISCUSSION...SIGNIFICANT RAINFALL IS EXPECTED WITH THUNDERSTORMS ON FRIDAY. MANY STORMS WILL BRING UP TO A HALF OF AN INCH AND SOME ONE INCH OR MORE...AND A FLASH FLOOD WATCH IS IN EFFECT FOR PORTIONS OF THE AREA. FIREFIGHTERS IN STEEP TERRAIN SHOULD WATCH FOR HEAVY RAIN AND BE PREPARED FOR DANGEROUS DEBRIS FLOWS. WISTER && .PRELIMINARY POINT TEMPS/POPS... PDT 68 92 64 86 / 20 30 30 20 ALW 72 94 68 87 / 20 30 30 20 PSC 70 98 69 91 / 10 20 20 10 YKM 69 97 66 90 / 10 20 20 10 HRI 71 96 68 90 / 20 20 20 20 ELN 69 93 65 86 / 10 20 20 10 RDM 58 84 55 82 / 40 30 20 20 LGD 52 86 56 79 / 40 60 60 60 GCD 59 88 58 84 / 50 70 60 60 DLS 72 88 68 83 / 20 20 10 10 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...RED FLAG WARNING UNTIL 9 PM PDT THIS EVENING FOR ORZ610-611- 640>645. FLASH FLOOD WATCH FROM FRIDAY AFTERNOON THROUGH FRIDAY EVENING FOR ORZ049-050-502-503-505-506. WA...RED FLAG WARNING UNTIL 9 PM PDT THIS EVENING FOR WAZ643-645. FLASH FLOOD WATCH FROM FRIDAY AFTERNOON THROUGH FRIDAY EVENING FOR WAZ030. && FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT... WWW.WEATHER.GOV/PENDLETON $$ 90/99/99/85
AREA FORECAST DISCUSSION
NWS MEDFORD OR
931 AM PDT THU JUL 9 2015 .DISCUSSION...THIS MORNING`S WATER VAPOR IMAGERY IS VERY TELLTALE OF HOW SIGNIFICANT THE DYNAMICS ARE SURROUNDING THE UPPER LOW OVER CALIFORNIA THAT HAS BEEN DICTATING OUR WEATHER FOR THE PAST SEVERAL DAYS. AT LEAST 6 IMPULSES CAN BE SEEN PINWHEELING AROUND THE UPPPER LOW...FROM THE COAST OF CALIFORNIA...RUNNING CLOCKWISE AROUND THE LOW TO NORTHWEST NEVADA. THESE UPSTREAM IMPUSLES IN NEVADA WILL HELP SPARK THUNDERSTORMS OVER THE FORECAST AREA TODAY AS THEY TRANSIT FROM EAST TO WEST. THE MAIN DIFFERENCE BETWEEN TODAY AND YESTERDAY IS THE DIFFERENCE IN CLOUD COVER. WHILE THERE ARE STILL SOME CLOUDS OVER THE INLAND AREAS THIS MORNING LIKE YESTERDAY...THEY ARE THINNER AND HAVE MORE BREAKS THAN THEY DID YESTERDAY...AND THE ORIENTATION OF THE CLOUD SHIELD SHOULD ALLOW FOR MORE SUNSHINE AND SURFACE HEATING TODAY. SO...WHERE THERE IS GOOD SUNSHINE TODAY GENERALLY EAST OF JOSEPHINE COUNTY...TO INCLUDE PARTS OF JACKSON COUNTY...NORTHERN CALIFORNIA...THE CASCADES...AND EAST SIDE...THERE WILL BE ENOUGH INSTABILITY TO GENERATE THUNDERSTORMS THIS AFTERNOON AND EVENING. HEAVY RAIN SHOULD ACCOMPANY SOME OF THESE STORMS MAINLY ALONG AND JUST WEST OF THE CASCADES...BASED ON PRECIPITABLE WATER VALUES OVER AN INCH. I HAVE ADDED HEAVY RAIN WORDING AND HAVE TONED DOWN THUNDERSTORM COVERAGE A LITTLE WEST OF THE CASCADES BASED ON MORNING ANALYSIS...BUT HAVE KEPT THE OVERALL IDEA OF THE FORECAST INTACT...WHICH CONVEYS A GOOD POTENTIAL FOR THUNDERSTORMS FOR MOST OF THE INLAND AREAS TODAY. PLEASE SEE THE PREVIOUS DISCUSSION BELOW FOR MORE DETAILS ON THE CURRENT FORECAST AND FIRE WEATHER DISCUSSION. && .AVIATION...FOR THE 09/12Z TAF CYCLE...FOR INLAND AREAS...VFR CONDITIONS ARE EXPECTED TO BE THE PREDOMINATE CONDITION TODAY THROUGH THIS EVENING, BUT TEMPORARY MVFR CIGS WITH REDUCED VISIBILITIES ARE POSSIBLE IN SHOWERS AND THUNDERSTORMS. SHOWERS AND THUNDERSTORM CHANCES WILL BE GREATEST FROM 21Z-04Z. STRONG GUSTY AND VARIABLE WINDS MAY ACCOMPANY STORMS. ALONG THE COAST...A MIX OF MFR/IFR CIGS WITH ISOLATED MVFR OR IFR VIS DUE TO FOG WILL CONTINUE THIS MORNING. AS WINDS BECOME SOUTHWESTERLY ALONG THE COAST TODAY, EXPECT AREAS OF MVFR CIGS TO CONTINUE DURING THE AFTERNOON WITH ONLY PARTIAL CLEARING ALONG THE COAST. THEN WIDESPREAD MVFR CIGS WITH ISOLATED IFR CIGS ARE EXPECTED THIS EVENING AND OVERNIGHT. /CC && .MARINE...UPDATED 230 AM PDT THURSDAY 9 JULY 2015...VARIABLE WINDS WILL SHIFT TO SOUTHWEST THIS AFTERNOON. LOW STRATUS AND PATCHY FOG THIS MORNING WILL PARTIALLY CLEAR AND LIFT TODAY BUT THEN EXPECT LOW STRATUS CLOUDS TO RETURN TONIGHT. SOUTH TO SOUTHWEST WINDS WILL DOMINATE LATE TODAY THROUGH THE WEEKEND AS LOW PRESSURE MOVES INTO THE PACIFIC NORTHWEST. WINDS AND WIND WAVES SHOULD STAY BELOW ADVISORY CRITERIA THROUGH THE WEEKEND. A THERMAL TROUGH IS EXPECTED RETURN TO THE COAST TUESDAY AND WEDNESDAY WITH INCREASED NORTH WINDS AND SHORT PERIOD SEAS. SMALL CRAFT ADVISORY CONDITIONS ARE POSSIBLE WITH THIS THERMAL TROUGH. SK && .FIRE WEATHER...UPDATED 240 AM PDT, THURSDAY 9 JULY 2015... LOW PRESSURE CENTERED NEAR MONTEREY BAY, CALIFORNIA WILL CONTINUE TO PIVOT LOW PRESSURE IMPULSES INTO THE AREA TODAY AND INTO FRIDAY AS IT DRIFTS INTO THE GREAT BASIN. THUNDERSTORM CHANCES ARE EXPECTED TO BE GREATEST TODAY FROM THE CASCADES EAST AND OVER NORTHERN CALIFORNIA. HOWEVER, SCATTERED THUNDERSTORMS ARE ALSO POSSIBLE WEST OF THE CASCADES IN JOSEPHINE AND JACKSON COUNTIES WITH ISOLATED THUNDERSTORMS FOR CURRY COUNTY. THERE IS SOME UNCERTAINTY FOR THE COVERAGE OF STORMS WEST OF THE CASCADES DUE TO INCREASED MID TO HIGH CLOUD COVER TODAY. THESE THUNDERSTORMS WILL BRING GUSTY AND ERRATIC WINDS, MODERATE TO LOCALLY HEAVY RAINFALL, AND THE POSSIBILITY OF HAIL IN STORM CORES. SOME SHOWERS AND ISOLATED THUNDERSTORMS MAY CONTINUE OVERNIGHT INTO FRIDAY MORNING. THEN MODELS ARE INDICATING A MIX OF SHOWERS AND THUNDERSTORMS FRIDAY FROM THE WESTERN SLOPES OF THE CASCADES EASTWARD AND ACROSS NORTHERN CALIFORNIA. ADDITIONAL WETTING RAIN IS EXPECTED WITH SHOWERS AND THUNDERSTORMS TODAY AND FRIDAY. A GRADUAL COOL DOWN IS STILL EXPECTED THROUGH THE WEEKEND. ALSO SOME BREEZY AND GUSTY SOUTHWEST WINDS ARE EXPECTED OVER AND EAST OF THE CASCADES THIS WEEKEND. /CC && .CLIMATE...YESTERDAY REPRESENTED THE FIRST DAY WITH BELOW NORMAL TEMPERATURES FOR MUCH OF THE FORECAST AREA IN THE PAST 35 DAYS. THAT IS QUITE REMARKABLE AND HIGHLIGHTS FURTHER HOW HOT A JUNE AND EARLY JULY IT HAS BEEN. && .PREV DISCUSSION... /ISSUED 442 AM PDT THU JUL 9 2015/ DISCUSSION...A CLOSED LOW LIES TO OUR SOUTH OVER CENTRAL AND SOUTHERN CALIFORNIA, LEAVING OUR FORECAST AREA ALONG THE NORTHERN PERIPHERY OF THE COUNTER CLOCKWISE FLOW. THROUGH TODAY, THIS LOW WILL BEGIN TO FILL IN AND SLIDE TO THE NORTHEAST. THE MOISTURE WILL CONTINUE TO FUNNEL INTO OUR REGION TODAY, BUT AS THE LOW MAKES ITS TREK, THE INFLOW WILL BEGIN TO WEAKEN A BIT. THIS WILL LEAVE TODAY AS THE LAST BEST DAY FOR THUNDERSTORMS, ALTHOUGH CHANCES WILL NOT GO AWAY COMPLETELY FOR A FEW MORE DAYS. MOISTURE AMOUNTS REMAIN VERY HIGH FOR THIS TIME OF YEAR, BUT THE MAIN CONCENTRATION WILL REMAIN JUST TO OUR SOUTH. HOWEVER, GIVEN THE AMOUNT OF PRECIPITABLE WATER IN THE REGION, STORMS TODAY ARE ONCE AGAIN LIKELY TO PRODUCE PERIODS OF HEAVY RAIN. MODEL SOLUTIONS ARE CONCENTRATING CONVECTION OVER NORTHERN CALIFORNIA AND ALONG THE CASCADES OF OREGON, AND SOME ARE SUGGESTING A LINE OF THUNDERSTORMS, LIKELY ASSOCIATED WITH A STRONG SHORTWAVE ORBITING THE LOW TO THE SOUTH, FORMING ALONG THE CASCADES AND PUSHING WEST ACROSS THE WESTERN FOOTHILLS OF THE CASCADES, AND INTO FAR SOUTHWESTERN OREGON. HAVE ADJUSTED THE FORECAST TO ACCOUNT FOR THIS, BUT THERE IS SOME UNCERTAINTY REGARDING THE TIMING OF THIS SHORTWAVE, AND THEREFORE THE PRECIPITATION AS WELL. THE NAM AND GFS BRING THE WAVE THROUGH IN THE LATE AFTERNOON AND EVENING, WHILE THE HIGHER RESOLUTION HRRR BRINGS IT IN SLIGHTLY EARLIER. THE LATER SOLUTION DOES APPEAR TO BE MOST LIKELY, GIVEN MODEL AGREEMENT, BUT CAN NOT RULE OUT A SLIGHTLY EARLIER ARRIVAL TIME. THE AMOUNT AND COVERAGE OF THUNDERSTORMS TODAY WILL ALSO DEPEND A GREAT DEAL ON THE AMOUNT OF CLOUDS OVERHEAD THROUGH THE MORNING AND EARLY AFTERNOON. SHOULD THE SHORTWAVE ARRIVE EARLIER, INCREASING CLOUDS WILL LIMIT HEATING, AND THEREFORE LIMIT CONVECTION. THIS SEEMS THE LESSER POSSIBILITY, BUT STILL A POSSIBILITY. A SECOND WEAKER SHORTWAVE WILL ARRIVE LATER, AND THIS COULD TOUCH OFF SOME SHOWERS AND PERHAPS A THUNDERSTORM, SHOULD ANY AREAS OF INSTABILITY REMAIN LATE IN THE EVENING AND INTO THE OVERNIGHT HOURS. AS THE LOW SHIFTS NORTHEAST FRIDAY, A SECOND TROUGH WILL BEGIN TO DIG IN ALONG THE COAST OF THE PACIFIC NORTHWEST. SOME RESIDUAL ENERGY AND INSTABILITY COULD TOUCH OF SOME MORE THUNDERSTORMS AND SHOWERS FRIDAY AFTERNOON AND EVENING, PARTICULARLY ACROSS THE CASCADES AND THE EAST SIDE, BUT CHANCES WILL BE LOWER THAN THE PREVIOUS DAYS, AND MOISTURE WILL NOT BE AS PREVALENT. THE TROUGH WILL ALSO BRING A CHANCE FOR MORE SHOWERS AND THUNDER SATURDAY AND SUNDAY AFTERNOONS, BUT COVERAGE WILL BE ON THE DECREASE, AND BY MONDAY AFTERNOON, ONLY SLIGHT CHANCE WILL REMAIN ALONG THE NORTHERN CASCADES AND EASTERN FOOTHILLS. EARLY NEXT WEEK, THE THERMAL TROUGH PATTERN RETURNS, AND PRECIPITATION CHANCES DROP TO NEAR NOTHING FOR THE REMAINDER OF THE FORECAST TERM. TEMPERATURES HAVE BEGUN THEIR DOWNWARD SWING AS THE COOLER AIR MASS FILTERS INTO THE AREA AND CLOUD COVER KEEPS THE INCOMING SUNLIGHT AT BAY. AS AN EXAMPLE, WEDNESDAY WAS THE FIRST IN FIFTEEN DAYS THAT THE TEMPERATURE DID NOT GET ABOVE 90 DEGREES IN MEDFORD. COOLER TEMPERATURES, ON THE ORDER OF 5 TO 10 DEGREES BELOW SEASONAL NORMALS, WILL CONTINUE THROUGH THE WEEKEND, BUT WILL BEGIN TO WARM AS THE THERMAL TROUGH PATTERN RETURNS EARLY NEXT WEEK. -BPN && .MFR WATCHES/WARNINGS/ADVISORIES... OR...NONE. CA...NONE. PACIFIC COASTAL WATERS...NONE. $$ NSK/NSK/BPN
AREA FORECAST DISCUSSION
NWS MEDFORD OR
442 AM PDT THU JUL 9 2015 UPDATED AVIATION DISCUSSION .DISCUSSION...A CLOSED LOW LIES TO OUR SOUTH OVER CENTRAL AND SOUTHERN CALIFORNIA, LEAVING OUR FORECAST AREA ALONG THE NORTHERN PERIPHERY OF THE COUNTER CLOCKWISE FLOW. THROUGH TODAY, THIS LOW WILL BEGIN TO FILL IN AND SLIDE TO THE NORTHEAST. THE MOISTURE WILL CONTINUE TO FUNNEL INTO OUR REGION TODAY, BUT AS THE LOW MAKES ITS TREK, THE INFLOW WILL BEGIN TO WEAKEN A BIT. THIS WILL LEAVE TODAY AS THE LAST BEST DAY FOR THUNDERSTORMS, ALTHOUGH CHANCES WILL NOT GO AWAY COMPLETELY FOR A FEW MORE DAYS. MOISTURE AMOUNTS REMAIN VERY HIGH FOR THIS TIME OF YEAR, BUT THE MAIN CONCENTRATION WILL REMAIN JUST TO OUR SOUTH. HOWEVER, GIVEN THE AMOUNT OF PRECIPITABLE WATER IN THE REGION, STORMS TODAY ARE ONCE AGAIN LIKELY TO PRODUCE PERIODS OF HEAVY RAIN. MODEL SOLUTIONS ARE CONCENTRATING CONVECTION OVER NORTHERN CALIFORNIA AND ALONG THE CASCADES OF OREGON, AND SOME ARE SUGGESTING A LINE OF THUNDERSTORMS, LIKELY ASSOCIATED WITH A STRONG SHORTWAVE ORBITING THE LOW TO THE SOUTH, FORMING ALONG THE CASCADES AND PUSHING WEST ACROSS THE WESTERN FOOTHILLS OF THE CASCADES, AND INTO FAR SOUTHWESTERN OREGON. HAVE ADJUSTED THE FORECAST TO ACCOUNT FOR THIS, BUT THERE IS SOME UNCERTAINTY REGARDING THE TIMING OF THIS SHORTWAVE, AND THEREFORE THE PRECIPITATION AS WELL. THE NAM AND GFS BRING THE WAVE THROUGH IN THE LATE AFTERNOON AND EVENING, WHILE THE HIGHER RESOLUTION HRRR BRINGS IT IN SLIGHTLY EARLIER. THE LATER SOLUTION DOES APPEAR TO BE MOST LIKELY, GIVEN MODEL AGREEMENT, BUT CAN NOT RULE OUT A SLIGHTLY EARLIER ARRIVAL TIME. THE AMOUNT AND COVERAGE OF THUNDERSTORMS TODAY WILL ALSO DEPEND A GREAT DEAL ON THE AMOUNT OF CLOUDS OVERHEAD THROUGH THE MORNING AND EARLY AFTERNOON. SHOULD THE SHORTWAVE ARRIVE EARLIER, INCREASING CLOUDS WILL LIMIT HEATING, AND THEREFORE LIMIT CONVECTION. THIS SEEMS THE LESSER POSSIBILITY, BUT STILL A POSSIBILITY. A SECOND WEAKER SHORTWAVE WILL ARRIVE LATER, AND THIS COULD TOUCH OFF SOME SHOWERS AND PERHAPS A THUNDERSTORM, SHOULD ANY AREAS OF INSTABILITY REMAIN LATE IN THE EVENING AND INTO THE OVERNIGHT HOURS. AS THE LOW SHIFTS NORTHEAST FRIDAY, A SECOND TROUGH WILL BEGIN TO DIG IN ALONG THE COAST OF THE PACIFIC NORTHWEST. SOME RESIDUAL ENERGY AND INSTABILITY COULD TOUCH OF SOME MORE THUNDERSTORMS AND SHOWERS FRIDAY AFTERNOON AND EVENING, PARTICULARLY ACROSS THE CASCADES AND THE EAST SIDE, BUT CHANCES WILL BE LOWER THAN THE PREVIOUS DAYS, AND MOISTURE WILL NOT BE AS PREVALENT. THE TROUGH WILL ALSO BRING A CHANCE FOR MORE SHOWERS AND THUNDER SATURDAY AND SUNDAY AFTERNOONS, BUT COVERAGE WILL BE ON THE DECREASE, AND BY MONDAY AFTERNOON, ONLY SLIGHT CHANCE WILL REMAIN ALONG THE NORTHERN CASCADES AND EASTERN FOOTHILLS. EARLY NEXT WEEK, THE THERMAL TROUGH PATTERN RETURNS, AND PRECIPITATION CHANCES DROP TO NEAR NOTHING FOR THE REMAINDER OF THE FORECAST TERM. TEMPERATURES HAVE BEGUN THEIR DOWNWARD SWING AS THE COOLER AIR MASS FILTERS INTO THE AREA AND CLOUD COVER KEEPS THE INCOMING SUNLIGHT AT BAY. AS AN EXAMPLE, WEDNESDAY WAS THE FIRST IN FIFTEEN DAYS THAT THE TEMPERATURE DID NOT GET ABOVE 90 DEGREES IN MEDFORD. COOLER TEMPERATURES, ON THE ORDER OF 5 TO 10 DEGREES BELOW SEASONAL NORMALS, WILL CONTINUE THROUGH THE WEEKEND, BUT WILL BEGIN TO WARM AS THE THERMAL TROUGH PATTERN RETURNS EARLY NEXT WEEK. -BPN && .AVIATION...FOR THE 09/12Z TAF CYCLE...FOR INLAND AREAS...VFR CONDITIONS ARE EXPECTED TO BE THE PREDOMINATE CONDITION TODAY THROUGH THIS EVENING, BUT TEMPORARY MVFR CIGS WITH REDUCED VISIBILITIES ARE POSSIBLE IN SHOWERS AND THUNDERSTORMS. SHOWERS AND THUNDERSTORM CHANCES WILL BE GREATEST FROM 21Z-04Z. STRONG GUSTY AND VARIABLE WINDS MAY ACCOMPANY STORMS. ALONG THE COAST...A MIX OF MFR/IFR CIGS WITH ISOLATED MVFR OR IFR VIS DUE TO FOG WILL CONTINUE THIS MORNING. AS WINDS BECOME SOUTHWESTERLY ALONG THE COAST TODAY, EXPECT AREAS OF MVFR CIGS TO CONTINUE DURING THE AFTERNOON WITH ONLY PARTIAL CLEARING ALONG THE COAST. THEN WIDESPREAD MVFR CIGS WITH ISOLATED IFR CIGS ARE EXPECTED THIS EVENING AND OVERNIGHT. /CC && .MARINE...UPDATED 230 AM PDT THURSDAY 9 JULY 2015...WEAK HIGH PRESSURE AND VARIABLE WINDS IS EXPECTED THIS MORNING...THEN WINDS WILL SHIFT TO SOUTHERLY THIS AFTERNOON. LOW STRATUS AND PATCHY FOG THIS MORNING WILL PARTIALLY CLEAR AND LIFT TODAY BUT THEN EXPECT LOW STRATUS CLOUDS TO RETURN TONIGHT. SOUTH TO SOUTHWEST WINDS WILL DOMINATE LATE TODAY THROUGH THE WEEKEND AS LOW PRESSURE MOVES INTO THE PACIFIC NORTHWEST. THESE WINDS AND WIND WAVES WILL BE LOW TO MODERATE IN THE NORTHERN WATERS FRIDAY INTO THE WEEKEND...AND WILL LIKELY REMAIN BELOW ADVISORY CRITERIA. SEAS OF 4 TO 6 FEET DUE TO MIXED NORTHWEST SWELL AND LONGER PERIOD SOUTH SWELL WILL CONTINUE THROUGH THE WEEKEND. A THERMAL TROUGH IS EXPECTED RETURN TO THE COAST WITH INCREASED NORTH WINDS AND SHORT PERIOD SEAS AROUND TUESDAY AND WEDNESDAY OF NEXT WEEK. SMALL CRAFT ADVISORY CONDITIONS ARE POSSIBLE WITH THIS THERMAL TROUGH. /CC && .FIRE WEATHER...UPDATED 240 AM PDT, THURSDAY 9 JULY 2015... LOW PRESSURE CENTERED NEAR MONTERREY BAY, CALIFORNIA WILL CONTINUE TO PIVOT LOW PRESSURE IMPULSES INTO THE AREA TODAY AND INTO FRIDAY AS IT DRIFTS INTO THE GREAT BASIN. THUNDERSTORM CHANCES ARE EXPECTED TO BE GREATEST TODAY FROM THE CASCADES EAST AND OVER NORTHERN CALIFORNIA. HOWEVER, SCATTERED THUNDERSTORMS ARE ALSO POSSIBLE WEST OF THE CASCADES IN JOSEPHINE AND JACKSON COUNTIES WITH ISOLATED THUNDERSTORMS FOR CURRY COUNTY. THERE IS SOME UNCERTAINTY FOR THE COVERAGE OF STORMS WEST OF THE CASCADES DUE TO INCREASED MID TO HIGH CLOUD COVER TODAY. THESE THUNDERSTORMS WILL BRING GUSTY AND ERRATIC WINDS, MODERATE TO LOCALLY HEAVY RAINFALL, AND THE POSSIBILITY OF HAIL IN STORM CORES. SOME SHOWERS AND ISOLATED THUNDERSTORMS MAY CONTINUE OVERNIGHT INTO FRIDAY MORNING. THEN MODELS ARE INDICATING A MIX OF SHOWERS AND THUNDERSTORMS FRIDAY FROM THE WESTERN SLOPES OF THE CASCADES EASTWARD AND ACROSS NORTHERN CALIFORNIA. ADDITIONAL WETTING RAIN IS EXPECTED WITH SHOWERS AND THUNDERSTORMS TODAY AND FRIDAY. A GRADUAL COOL DOWN IS STILL EXPECTED THROUGH THE WEEKEND. ALSO SOME BREEZY AND GUSTY SOUTHWEST WINDS ARE EXPECTED OVER AND EAST OF THE CASCADES THIS WEEKEND. /CC && .MFR WATCHES/WARNINGS/ADVISORIES... OR...NONE. CA...NONE. PACIFIC COASTAL WATERS...NONE. $$ BPN/CC
AREA FORECAST DISCUSSION
NWS MEDFORD OR
248 AM PDT THU JUL 9 2015 .DISCUSSION...A CLOSED LOW LIES TO OUR SOUTH OVER CENTRAL AND SOUTHERN CALIFORNIA, LEAVING OUR FORECAST AREA ALONG THE NORTHERN PERIPHERY OF THE COUNTER CLOCKWISE FLOW. THROUGH TODAY, THIS LOW WILL BEGIN TO FILL IN AND SLIDE TO THE NORTHEAST. THE MOISTURE WILL CONTINUE TO FUNNEL INTO OUR REGION TODAY, BUT AS THE LOW MAKES ITS TREK, THE INFLOW WILL BEGIN TO WEAKEN A BIT. THIS WILL LEAVE TODAY AS THE LAST BEST DAY FOR THUNDERSTORMS, ALTHOUGH CHANCES WILL NOT GO AWAY COMPLETELY FOR A FEW MORE DAYS. MOISTURE AMOUNTS REMAIN VERY HIGH FOR THIS TIME OF YEAR, BUT THE MAIN CONCENTRATION WILL REMAIN JUST TO OUR SOUTH. HOWEVER, GIVEN THE AMOUNT OF PRECIPITABLE WATER IN THE REGION, STORMS TODAY ARE ONCE AGAIN LIKELY TO PRODUCE PERIODS OF HEAVY RAIN. MODEL SOLUTIONS ARE CONCENTRATING CONVECTION OVER NORTHERN CALIFORNIA AND ALONG THE CASCADES OF OREGON, AND SOME ARE SUGGESTING A LINE OF THUNDERSTORMS, LIKELY ASSOCIATED WITH A STRONG SHORTWAVE ORBITING THE LOW TO THE SOUTH, FORMING ALONG THE CASCADES AND PUSHING WEST ACROSS THE WESTERN FOOTHILLS OF THE CASCADES, AND INTO FAR SOUTHWESTERN OREGON. HAVE ADJUSTED THE FORECAST TO ACCOUNT FOR THIS, BUT THERE IS SOME UNCERTAINTY REGARDING THE TIMING OF THIS SHORTWAVE, AND THEREFORE THE PRECIPITATION AS WELL. THE NAM AND GFS BRING THE WAVE THROUGH IN THE LATE AFTERNOON AND EVENING, WHILE THE HIGHER RESOLUTION HRRR BRINGS IT IN SLIGHTLY EARLIER. THE LATER SOLUTION DOES APPEAR TO BE MOST LIKELY, GIVEN MODEL AGREEMENT, BUT CAN NOT RULE OUT A SLIGHTLY EARLIER ARRIVAL TIME. THE AMOUNT AND COVERAGE OF THUNDERSTORMS TODAY WILL ALSO DEPEND A GREAT DEAL ON THE AMOUNT OF CLOUDS OVERHEAD THROUGH THE MORNING AND EARLY AFTERNOON. SHOULD THE SHORTWAVE ARRIVE EARLIER, INCREASING CLOUDS WILL LIMIT HEATING, AND THEREFORE LIMIT CONVECTION. THIS SEEMS THE LESSER POSSIBILITY, BUT STILL A POSSIBILITY. A SECOND WEAKER SHORTWAVE WILL ARRIVE LATER, AND THIS COULD TOUCH OFF SOME SHOWERS AND PERHAPS A THUNDERSTORM, SHOULD ANY AREAS OF INSTABILITY REMAIN LATE IN THE EVENING AND INTO THE OVERNIGHT HOURS. AS THE LOW SHIFTS NORTHEAST FRIDAY, A SECOND TROUGH WILL BEGIN TO DIG IN ALONG THE COAST OF THE PACIFIC NORTHWEST. SOME RESIDUAL ENERGY AND INSTABILITY COULD TOUCH OF SOME MORE THUNDERSTORMS AND SHOWERS FRIDAY AFTERNOON AND EVENING, PARTICULARLY ACROSS THE CASCADES AND THE EAST SIDE, BUT CHANCES WILL BE LOWER THAN THE PREVIOUS DAYS, AND MOISTURE WILL NOT BE AS PREVALENT. THE TROUGH WILL ALSO BRING A CHANCE FOR MORE SHOWERS AND THUNDER SATURDAY AND SUNDAY AFTERNOONS, BUT COVERAGE WILL BE ON THE DECREASE, AND BY MONDAY AFTERNOON, ONLY SLIGHT CHANCE WILL REMAIN ALONG THE NORTHERN CASCADES AND EASTERN FOOTHILLS. EARLY NEXT WEEK, THE THERMAL TROUGH PATTERN RETURNS, AND PRECIPITATION CHANCES DROP TO NEAR NOTHING FOR THE REMAINDER OF THE FORECAST TERM. TEMPERATURES HAVE BEGUN THEIR DOWNWARD SWING AS THE COOLER AIR MASS FILTERS INTO THE AREA AND CLOUD COVER KEEPS THE INCOMING SUNLIGHT AT BAY. AS AN EXAMPLE, WEDNESDAY WAS THE FIRST IN FIFTEEN DAYS THAT THE TEMPERATURE DID NOT GET ABOVE 90 DEGREES IN MEDFORD. COOLER TEMPERATURES, ON THE ORDER OF 5 TO 10 DEGREES BELOW SEASONAL NORMALS, WILL CONTINUE THROUGH THE WEEKEND, BUT WILL BEGIN TO WARM AS THE THERMAL TROUGH PATTERN RETURNS EARLY NEXT WEEK. -BPN && .AVIATION...FOR THE 09/06Z TAF CYCLE...FOR INLAND AREAS...VFR CONDITIONS ARE EXPECTED TO BE THE PREDOMINATE CONDITION TODAY THROUGH THIS EVENING, BUT TEMPORARY MVFR CIGS WITH REDUCED VISIBILITIES ARE POSSIBLE IN SHOWERS AND THUNDERSTORMS. SHOWERS AND THUNDERSTORM CHANCES WILL BE GREATEST FROM 21Z-04Z. STRONG GUSTY AND VARIABLE WINDS MAY ACCOMPANY STORMS. ALONG THE COAST...A MIX OF MFR/IFR CIGS WITH ISOLATED MVFR OR IFR VIS DUE TO FOG WILL CONTINUE THIS MORNING. CONDITIONS WILL CLEAR TO VFR DURING THE LATE MORNING AND EARLY AFTERNOON, THEN A MIX OF MVFR/IFR CIGS WILL RETURN DURING THE EVENING HOURS BETWEEN 01Z-04Z. /CC && .MARINE...UPDATED 230 AM PDT THURSDAY 9 JULY 2015...WEAK HIGH PRESSURE AND VARIABLE WINDS IS EXPECTED THIS MORNING...THEN WINDS WILL SHIFT TO SOUTHERLY THIS AFTERNOON. LOW STRATUS AND PATCHY FOG THIS MORNING WILL PARTIALLY CLEAR AND LIFT TODAY BUT THEN EXPECT LOW STRATUS CLOUDS TO RETURN TONIGHT. SOUTH TO SOUTHWEST WINDS WILL DOMINATE LATE TODAY THROUGH THE WEEKEND AS LOW PRESSURE MOVES INTO THE PACIFIC NORTHWEST. THESE WINDS AND WIND WAVES WILL BE LOW TO MODERATE IN THE NORTHERN WATERS FRIDAY INTO THE WEEKEND...AND WILL LIKELY REMAIN BELOW ADVISORY CRITERIA. SEAS OF 4 TO 6 FEET DUE TO MIXED NORTHWEST SWELL AND LONGER PERIOD SOUTH SWELL WILL CONTINUE THROUGH THE WEEKEND. A THERMAL TROUGH IS EXPECTED RETURN TO THE COAST WITH INCREASED NORTH WINDS AND SHORT PERIOD SEAS AROUND TUESDAY AND WEDNESDAY OF NEXT WEEK. SMALL CRAFT ADVISORY CONDITIONS ARE POSSIBLE WITH THIS THERMAL TROUGH. /CC && .FIRE WEATHER...UPDATED 240 AM PDT, THURSDAY 9 JULY 2015... LOW PRESSURE CENTERED NEAR MONTERREY BAY, CALIFORNIA WILL CONTINUE TO PIVOT LOW PRESSURE IMPULSES INTO THE AREA TODAY AND INTO FRIDAY AS IT DRIFTS INTO THE GREAT BASIN. THUNDERSTORM CHANCES ARE EXPECTED TO BE GREATEST TODAY FROM THE CASCADES EAST AND OVER NORTHERN CALIFORNIA. HOWEVER, SCATTERED THUNDERSTORMS ARE ALSO POSSIBLE WEST OF THE CASCADES IN JOSEPHINE AND JACKSON COUNTIES WITH ISOLATED THUNDERSTORMS FOR CURRY COUNTY. THERE IS SOME UNCERTAINTY FOR THE COVERAGE OF STORMS WEST OF THE CASCADES DUE TO INCREASED MID TO HIGH CLOUD COVER TODAY. THESE THUNDERSTORMS WILL BRING GUSTY AND ERRATIC WINDS, MODERATE TO LOCALLY HEAVY RAINFALL, AND THE POSSIBILITY OF HAIL IN STORM CORES. SOME SHOWERS AND ISOLATED THUNDERSTORMS MAY CONTINUE OVERNIGHT INTO FRIDAY MORNING. THEN MODELS ARE INDICATING A MIX OF SHOWERS AND THUNDERSTORMS FRIDAY FROM THE WESTERN SLOPES OF THE CASCADES EASTWARD AND ACROSS NORTHERN CALIFORNIA. ADDITIONAL WETTING RAIN IS EXPECTED WITH SHOWERS AND THUNDERSTORMS TODAY AND FRIDAY. A GRADUAL COOL DOWN IS STILL EXPECTED THROUGH THE WEEKEND. ALSO SOME BREEZY AND GUSTY SOUTHWEST WINDS ARE EXPECTED OVER AND EAST OF THE CASCADES THIS WEEKEND. /CC && .MFR WATCHES/WARNINGS/ADVISORIES... OR...NONE. CA...NONE. PACIFIC COASTAL WATERS...NONE. $$ BPN/CC
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
248 PM EDT THU JUL 9 2015 .SYNOPSIS... AN UPPER RIDGE WILL PREVAIL OVER THE SOUTHEAST THROUGH THE WEEKEND...BEFORE SLIDING WEST BY EARLY NEXT WEEK. UPPER LEVEL DISTURBANCES AND A COLD FRONT WILL APPROACH THE REGION EARLY NEXT WEEK. && .NEAR TERM /THROUGH FRIDAY/... AS OF 215 PM EDT...VERY LITTLE CUMULUS DEVELOPMENT HAS BEEN OBSERVED ACROSS THE REGION THIS AFTN AS SFC DEWPOINTS HAVE MIXED OUT INTO THE LOWER 60S MOST AREAS...AND EVEN UPPER 50S IN OTHERS. THIS HAS CAPPED SBCAPE VALUES AT LESS THAN 1000 J/KG...AND WEAK CAPPING ALOFT WILL FURTHER SERVE TO CURTAIL LATE DAY CONVECTION...EXCEPT FOR PERHAPS ISOLD WEAK RIDGE TOP SHOWERS/TSRA. THE HRRR DOES FEATURE SCATTERED NC FOOTHILLS CONVECTION DEVELOPING CIRCA 19Z...BUT THIS WILL BE A STRUGGLE GIVEN THE MIXED OUT DEWPOINTS. OTHERWISE...AN H5 RIDGE WILL PERSIST FROM THE LOWER MS VALLEY TO THE SE COAST THROUGH THE NEAR TERM PERIOD...WITH ANY SHORTWAVE ENERGY RIDING MAINLY BY TO THE NORTH OF THE AREA. AT THE SURFACE...A COLD FRONT WILL REMAIN DRAPED N OF THE AREA THROUGH TONIGHT. THE BOUNDARY MAY MAKE SOME PROGRESS SWD INTO THE NRN TIER THROUGH THE DAY ON FRI. NW FLOW IS EXPECTED TO IMPROVE SOMEWHAT ACROSS THE NRN TIER...BUT THERE IS CONSIDERABLE CINH IN SOUNDINGS THROUGH MOST OF THE DAY TO ONCE AGAIN LIMIT INSTABILITY AND TSTM POTENTIAL DURING PEAK HEATING. THERE SHOULD BE AN AREA OF CONVECTION DEVELOPING OVER THE LOWER OH VALLEY FRI WHICH MAY MAKE A RUN EASTWARD TOWARD THE NRN NC MTNS LATE IN THE DAY. AND...A FEW MODELS DEPICT ISOLD ACTIVITY OUT ALONG THE INTERSTATE 40 CORRIDOR THROUGH EARLY EVENING ALONG AND AHEAD OF THE BOUNDARY. EXPECT WARM MINS AND MAXES ABOUT TWO CATEGORIES ABOVE CLIMO THROUGHOUT. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/... AS OF 230 PM EDT THURSDAY...THE SHORT TERM FORECAST PERIOD BEGINS FRIDAY NIGHT WITH A 593DM 500MB RIDGE CENTERED OVER THE LOWER MS RIVER VALLEY. ALONG THE NORTHERN PERIPHERY OF THE RIDGE LIES THE SHORTWAVE TRACK ACROSS THE OH RIVER VALLEY AND THE MID-ATLANTIC. AT THE SURFACE A VERY WEAK FRONTAL BOUNDARY WILL STRETCH FROM EAST TO WEST NEAR THE NC/SC STATELINE ASSOCIATED WITH A LOW-PRESSURE SYSTEM LOCATED OFF THE NEW ENGLAND COAST. THERE STILL APPEARS TO BE A CHANCE FOR UPSTREAM OVERNIGHT CONVECTION TO PROPAGATE ACROSS SE KY...SW VA...AND E TN AND IMPACT THE WESTERN AND NORTHERN PORTIONS OF OUR FORECAST AREA BUT THERE REMAINS PLENTY OF UNCERTAINTY IN THE DETAILS TO WARRANT SIGNIFICANT CHANGES TO THE FORECAST AT THIS TIME. HEADING INTO SATURDAY THE 500MB RIDGE RETROGRADES FURTHER WEST INTO THE SOUTHERN PLAINS PLACING THE FORECAST AREA IN NORTHWEST FLOW ALOFT. MODELS ARE IN GOOD AGREEMENT ABOUT BRING THE FRONTAL BOUNDARY THROUGH THE FORECAST AREA...STALLING THE FRONT ACROSS SOUTHERN GA AND EXTENDING NORTHEAST ALONG THE ATLANTIC COAST...PLACING THE AREA IN GENERAL NORTHWESTERLY FLOW IN THE LOWER LEVELS AS WELL. GUIDANCE BRINGS A FAIRLY STRONG SHORTWAVE THROUGH THE FLOW ALOFT ACROSS VIRGINIA AND INTO NE NC HEADING INTO SATURDAY NIGHT AND THE ASSOCIATED CONVECTIVE COMPLEX STAYS NORTH OF OUR AREA AT THIS TIME. HOWEVER...THE NAM IS ALSO BRINGING A SECONDARY SHORTWAVE ACROSS THE TN RIVER VALLEY DURING THE DAY ON SATURDAY WHICH COMBINED WITH THE UNCERTAINTY ASSOCIATED WITH THE GENERAL SHORTWAVE TRACK JUSTIFIES CHANCE POPS ACROSS THE MOUNTAINS AND THE NC PORTION OF OUR FORECAST AREA. ON SUNDAY WE REMAIN IN GENERAL NORTHWESTERLY FLOW THROUGH THE COLUMN WITH THE RESIDUAL SURFACE FRONT REMAINING ALONG THE SC COASTAL PLAIN AND EXTENDING OFFSHORE. WITH THE LACK OF SIGNIFICANT SHORTWAVE ENERGY PROPAGATING THROUGH THE FLOW...SUNDAY APPEARS TO SUPPORT CONTINUE LOW END CHANCE POPS ACROSS THE MOUNTAINS WHERE THE INSTABILITY WILL BE MOST FAVORABLE FOR AFTERNOON CONVECTION. ONCE AGAIN THE NAM IS MORE AGGRESSIVE WITH BRINGING SHORTWAVE ENERGY CLOSER TO OUR FORECAST AREA SUNDAY EVENING SO WE MAINTAINED CHANCE POPS EXTENDING FROM THE MOUNTAINS TO THE FOOTHILLS AND PIEDMONT OF NC AS WELL. && .LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/... AT 200 PM EDT THURSDAY...ON SUNDAY NIGHT AN UPPER RIDGE WILL BE CENTERED OVER TX...EXTENDING NORTHWARD OVER THE PLAINS...AND EASTWARD OVER THE GULF STATES. MEANWHILE...A LOW AMPLITUDE UPPER TROUGH WILL BE ALONG THE EAST COAST. SHORTWAVE ENERGY MOVING THROUGH THIS TROUGH WILL INITIALLY BE CHANNELED WELL TO OUR NORTH. AS THE UPPER RIDGE RETROGRESSES TOWARD THE SOUTHERN ROCKIES MONDAY NIGHT...THE EASTERN TROUGH AMPLIFIES...AND CHANNELED SHORTWAVE ENERGY APPROACHES THE SOUTHERN APPALACHIANS. SEVERAL SHORTWAVES CROSS OUR AREA FROM MONDAY NIGHT THROUGH THURSDAY. AT THE SURFACE...A WEAKENING COLD FRONT IS EXPECTED TO CROSS OUR AREA ON MONDAY OR TUESDAY...DESPENING ON MODEL TIMING. THE FRONT STALLS JUST TO OUR SE AND REMAINS THERE THROUGH WEDNESDAY. THE REMAINS OF THIS WEAKENING BOUNDARY MOVE OFF TO THE SOUTHEAST ON THURSDAY. THIS PATTERN WILL RESULT IN FALLING HEIGHTS ALOFT...AND GREATER INSTABILITY THAT WILL ONLY PARTIALLY DIMINISH EACH NIGHT WITH THE LOSS OF DAYTIME HEATING...FAVORING A BETTER CHANCE OF OVERNIGHT CONVECTION. VARYING AMOUNTS OF SHEAR WILL BE PRESENT MUCH OF THE TIME...BUT STEERING FLOW WILL BE SUFFICIENT TO KEEP CELLS MOVING...AND UPSLOPE FLOW WILL GENERALLY BE LIMITED TO THE WEST SLOPES OF THE APPALACHIANS. TEMPERATURES WILL COOL SLIGHTLY... APPROACHING NORMAL VALUES FOR THIS TIME OF YEAR. && .AVIATION /19Z THURSDAY THROUGH TUESDAY/... AT KCLT AND ELSEWHERE...ANY THUNDERSTORMS CLOSER TO THE FRONT NORTH OF THE REGION WILL STAY WELL NORTH OF THE AIRFIELD THIS AFTN. THE HRRR DOES HINT AT ISOLD DEVELOPMENT JUST EAST OF THE BLUE RIDGE....BUT DEWPOINTS IN THIS AREA HAVE MIXED INTO THE UPPER 50S SO THIS APPEARS OVERDONE. EXPECT MAINLY FEW TO SCT HIGH CLOUDS...WITH SOME CUMULUS DEVELOPING ALONG THE MTN RIDGES BOTH LATE AFTN TODAY AND AGAIN FRI MORNING. LOW END WIND GUSTS WILL BE POSSIBLE UNTIL SUNDOWN...WITH MAINLY WSW FLOW EAST OF THE MTN AND NW WINDS AT KAVL. FLOW SHOULD COME UP FROM THE NW THROUGHOUT WITH MIXING LATE FRI MORNING. OUTLOOK...A WEAK FRONTAL ZONE WILL SETTLE SOUTHWARD THROUGH THE AREA THIS WEEKEND TO PERMIT SCATTERED THUNDERSTORM DEVELOPMENT. COVERAGE WILL LIKELY INCREASE EARLY TO MIDDLE NEXT WEEK AHEAD OF AN APPROACHING COLD FRONT FROM THE NW. RESTRICTIONS WILL BE POSSIBLE UNDER ANY CONVECTION. LOW CLOUDS AND FOG COULD ALSO DEVELOP IN THE MORNING AT PLACES THAT HAVE SHOWER ACTIVITY THE DAY BEFORE...AND IN MTN AND RIVER VALLEYS. CONFIDENCE TABLE... 18-24Z 00-06Z 06-12Z 12-18Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...JAT NEAR TERM...HG/WIMBERLEY SHORT TERM...JMP LONG TERM...JAT AVIATION...HG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
159 PM EDT THU JUL 9 2015 .SYNOPSIS... AN UPPER RIDGE WILL PREVAIL OVER THE SOUTHEAST THROUGH THE WEEKEND...BEFORE SLIDING WEST BY EARLY NEXT WEEK. UPPER LEVEL DISTURBANCES AND A COLD FRONT WILL APPROACH THE REGION EARLY NEXT WEEK. && .NEAR TERM /THROUGH FRIDAY/... AS OF 145 PM EDT...VERY LITTLE CUMULUS DEVELOPMENT HAS BEEN OBSERVED ACROSS THE REGION THIS AFTN AS SFC DEWPOINTS HAVE MIXED OUT INTO THE LOWER 60S MOST AREAS. THIS HAS CAPPED SBCAPE VALUES AT LESS THAN 1000 J/KG...AND WEAK CAPPING ALOFT WILL FURTHER SERVE TO CURTAIL LATE DAY CONVECTION...EXCEPT FOR PERHAPS ISOLD WEAK RIDGE TOP SHOWERS/TSRA. THE HRRR HAS SCT NC FOOTHILLS CONVECTION DEVELOPING CIRCA 19Z...BUT THIS WILL BE A STRUGGLE GIVEN THE MIXED OUT DEWPOINTS. OTHERWISE...AN H5 RIDGE WILL PERSIST FROM THE LOWER MS VALLEY TO THE SE COAST THROUGH THE NEAR TERM PERIOD...WITH ANY SHORTWAVE ENERGY RIDING MAINLY BY TO THE NORTH OF THE AREA. AT THE SURFACE...A COLD FRONT WILL REMAIN DRAPED N OF THE AREA THROUGH TONIGHT. THE BOUNDARY MAY MAKE SOME PROGRESS SWD INTO THE NRN TIER LATE DAY. IN ADDITION...NW FLOW WILL IMPROVE SOMEWHAT ACROSS THE NRN TIER...BUT THERE IS CONSIDERABLE CINH IN SOUNDINGS THROUGH MOST OF THE DAY TO ONCE AGAIN LIMIT INSTABILITY AND TSTM POTENTIAL. THERE SHOULD BE AN AREA OF CONVECTION DEVELOPING OVER THE LOWER OH VALLEY FRI WHICH MAY MAKE A RUN EASTWARD TOWARD THE NRN NC MTNS LATE IN THE DAY. A FEW MODELS ALSO DEPICT ISOLD ACTIVITY OUT ALONG THE INTERSTATE 40 CORRIDOR THROUGH EARLY EVENING ALONG AND AHEAD OF THE BOUNDARY. EXPECT WARM MINS AND MAXES ABOUT TWO CATEGORIES ABOVE CLIMO. && .SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/... AS OF 300 AM EDT THURSDAY...THE SHORT TERM FCST PERIOD INITIALIZES FRIDAY MORNING WITH A 592DM H5 RIDGE CENTERED OVER THE SOUTHEAST WHILE A SERIES OF SHORTWAVE IMPULSES SLIDE ATOP THE RIDGE OVER THE MID MISSISSIPPI AND OHIO RIVER VALLEYS. BENEATH THESE SHORTWAVES AT THE SURFACE...AN EAST/WEST ORIENTED FRONTAL AXIS WILL STRETCH FROM THE MID ATLANTIC COAST INTO THE SOUTHERN/CENTRAL PLAINS STATES. THERMAL PROFILES ON FRIDAY LOOK TO FAVOR SOME LOW LEVEL CIN AND POOR LAPSE RATES ALOFT THANKS THE RIDGE...ESPECIALLY OVER THE SOUTHWESTERN TIER OF THE FCST AREA. SOUNDINGS FURTHER NORTH AND EAST OVER WESTERN NC AND PORTIONS OF THE UPSTATE ARE A TAD MORE UNSTABLE WITH LESS CIN IN THE LOW LEVELS. MODELS LEAN TOWARD ISOLATED DIURNAL CONVECTION ON FRIDAY AFTERNOON OVER THESE MORE FAVORABLE ZONES. IN ADDITION...UPSTREAM MCS PROPAGATION ALSO COMES INTO PLAY LATE IN THE EVENING/OVERNIGHT FOR THE WESTERN NC MTNS AS NEARLY ALL GUIDANCE FAVORS SOME DEVELOPMENT OVER SOUTHEAST KY AND MIDDLE/EAST TN. EXPECTING A RATHER DEEP MIXED LAYER WITH DRY PROFILES ALOFT THUS SOME THUNDERSTORMS ON FRIDAY COULD BE STRONG/SEVERE WITH DAMAGING WINDS BEING THE PRIMARY THREATS. POPS ON FRIDAY FEATURE SLIGHT CHANCES OVER THE NC/SC PIEDMONT AND FOOTHILLS WITH CHANCE POPS OVER THE MTNS. MODELS TRY TO SAG THE OLD FRONTAL AXIS INTO THE REGION ON SATURDAY...HOWEVER WITH SOME OF THE DETAILS BEING UNCLEAR SUCH AS TIMING AND DEPTH OF THE INTRUSION. THE NAM BEING THE MOST AGGRESSIVE PUSHES THE BOUNDARY WELL INTO WESTERN NC...PERHAPS AS FAR SOUTH AS THE NC/SC STATELINE. THE GFS/ECMWF ARE A TAD LESS AGGRESSIVE AS THEY KEEP THE AXIS A HUNDRED OR SO MILES FURTHER NORTH. NEVERTHELESS...ALL GUID FAVORS CONVECTION ALONG OR JUST AHEAD OF THE FRONTAL AXIS WITH PERHAPS YET ANOTHER UPSTREAM MCS RIDING THE NW FLOW ALOFT INTO THE REGION SATURDAY EVENING. PROFILES ARE A BIT MORE MOIST ON SATURDAY THEREFORE LAPSE RATES AREA POORER WHICH SHOULD LIMIT ANY DEEP STRONG/SEVERE CONVECTION. THE PRIMARY HAZARDS WITH ANY STORMS ON SATURDAY COULD BE WET MICROBURSTS AND HEAVY RAINFALL...HOWEVER CONFIDENCE ON BOTH IS LOW AT THIS TIME. FCST POPS ON SATURDAY FAVOR CHANCE POPS ACROSS MUCH OF WESTERN NC AND SLIGHT CHANCE POPS FURTHER SOUTH INTO NORTHEAST GA AND UPSTATE SC. THE ABOVE MENTIONED FRONT DOES LOOK PUSH FURTHER SOUTH SATURDAY EVENING INTO SUNDAY MORNING...PERHAPS AS FAR AS THE SC MIDLANDS. TEMPERATURES THROUGH THE ENTIRE SHORT TERM PERIOD WILL REMAIN GENERALLY 4-6 DEGREES ABOVE NORMAL. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 330 AM EDT THURSDAY...THE MEDIUM RANGE FCST PERIOD INITIALIZES SUNDAY MORNING AMIDST FURTHER RETROGRESSION OF THE UPPER ANTICYCLONE INTO THE SOUTHERN PLAINS ALLOWING HEIGHTS TO SLOWLY FALL ACROSS THE SOUTHEAST....WHILE A SHORTWAVE BUILDS OVER THE SOUTHERN GREAT LAKES. AT THE SURFACE...ALTHOUGH STILL SOMEWHAT UNCLEAR...MODELS LEAN TOWARDS A SOLUTION THAT WOULD PLACE THE OLD FRONTAL AXIS DIRECTLY OVERHEAD...OR JUST SOUTH OF THE FCST AREA. GUIDANCE DOES FAVOR ISOLATED/SCATTERED ACTIVITY ON SUNDAY...HOWEVER CONFIDENCE IS LOW GIVEN THE UNCERTAINTY OF THE BOUNDARY LOCATION. THUS WILL KEEP POPS AT OR A TAD BELOW CLIMO FOR THE ENTIRE REGION ON SUNDAY. PRECIPITATION CHANCES WILL START TO INCREASE INTO THE START OF THE NEW WORK WEEK AS LOW LEVEL FLOW LOOKS TO VEER SOUTHERLY YIELDING INCREASED MOISTURE AND SLIGHTLY MORE FAVORABLE PROFILES FOR DIURNAL SHOWERS AND THUNDERSTORMS. TUESDAY AND WEDNESDAY LEND THEMSELVES TO EVEN HIGHER PRECIPITATION CHANCES THANKS TO A BUILDING/DIVING UPPER SHORTWAVE AND AN ASSOCIATED SFC COLD FRONT WHICH COULD SWING INTO THE PICTURE LATE IN THE PERIOD. TEMPERATURES WILL COOL SOMEWHAT THROUGH THE MEDIUM RANGE AS THE UPPER RIDGE REMAINS TO THE WEST...HOWEVER STILL EXPECTING HIGHS AT OR JUST ABOVE NORMAL. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... AT KCLT AND ELSEWHERE...ANY THUNDERSTORMS CLOSER TO THE FRONT NORTH OF THE REGION WILL STAY WELL NORTH OF THE AIRFIELD THIS AFTN. THE HRRR DOES HINT AT ISOLD DEVELOPMENT JUST EAST OF THE BLUE RIDGE....BUT DEWPOINTS IN THIS AREA HAVE MIXED INTO THE UPPER 50S SO THIS APPEARS OVERDONE. EXPECT MAINLY FEW TO SCT HIGH CLOUDS...WITH SOME CUMULUS DEVELOPING ALONG THE MTN RIDGES BOTH LATE AFTN TODAY AND AGAIN FRI MORNING. LOW END WIND GUSTS WILL BE POSSIBLE UNTIL SUNDOWN...WITH MAINLY WSW FLOW EAST OF THE MTN AND NW WINDS AT KAVL. FLOW SHOULD COME UP FROM THE NW THROUGHOUT WITH MIXING LATE FRI MORNING. OUTLOOK...A WEAK FRONTAL ZONE WILL SETTLE SOUTHWARD THROUGH THE AREA THIS WEEKEND TO PERMIT SCATTERED THUNDERSTORM DEVELOPMENT. COVERAGE WILL LIKELY INCREASE EARLY TO MIDDLE NEXT WEEK AHEAD OF AN APPROACHING COLD FRONT FROM THE NW. RESTRICTIONS WILL BE POSSIBLE UNDER ANY CONVECTION. LOW CLOUDS AND FOG COULD ALSO DEVELOP IN THE MORNING AT PLACES THAT HAVE SHOWER ACTIVITY THE DAY BEFORE...AND IN MTN AND RIVER VALLEYS. CONFIDENCE TABLE... 18-24Z 00-06Z 06-12Z 12-18Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...JAT NEAR TERM...HG/WIMBERLEY SHORT TERM...CDG LONG TERM...CDG AVIATION...HG
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
956 AM CDT THU JUL 9 2015 .UPDATE... ALL OF MIDDLE TN IS DRY THIS MORNING WITH E-W BOUNDARY TO THE NORTH IN CENTRAL KY. HRRR KEEPS THE CWA MAINLY DRY THROUGHOUT THE DAY WITH PERHAPS A COUPLE OF ISOLATED THUNDERSTORMS POSSIBLE IN THE NORTH. POP GRIDS REFLECT THIS WELL. HOURLY GRIDS ARE LOOKING GOOD WITH THE WARM UP THIS MORNING. NO CHANGES NEEDED AT THIS TIME. REAGAN && .PREV DISCUSSION... /ISSUED 509 AM CDT THU JUL 9 2015/ 12Z AVIATION UPDATE... WEAK BOUNDARY REMAINS JUST NORTH OF THE AREA THROUGH MOST OF THE PERIOD. THIS WILL PUT A VERY SMALL CHANCE OF STORMS IN THE CKV VICINITY LATE TODAY INTO TONIGHT....POSSIBLY EVEN BNA. OUTSIDE OF A BRIEF STORM...VFR CONDITIONS ARE EXPECTED UNTIL LIGHT FOG DEVELOPMENT OVERNIGHT INTO EARLY FRIDAY. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 93 71 91 71 / 20 20 20 20 CLARKSVILLE 90 70 91 70 / 30 20 20 20 CROSSVILLE 89 67 84 66 / 10 20 20 20 COLUMBIA 94 70 93 71 / 10 10 10 10 LAWRENCEBURG 94 70 93 71 / 10 10 10 10 WAVERLY 91 71 92 70 / 20 20 10 10 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 10
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
339 AM CDT THU JUL 9 2015 .DISCUSSION... SFC LOW POSITIONED OVER INDIANA THIS MORNING. COLD FRONT EXTENDS SOUTHWARD ACROSS THE MO BOOTHEEL AND INTO EASTERN AR. OUT AHEAD OF THIS FEATURE...AN AREA OF SHOWERS AND TSTMS EXTENDS AS FAR SOUTH AS THE TN/KY BORDER. LATEST HRRR DOES SHOW ISOL ACTIVITY MOVING ACROSS THE NORTHERN PORTIONS OF THE MID STATE LATER TODAY. THUS...WILL INCLUDE A SLIGHT CHANCE OF SHOWERS AND TSTMS...BUT ONLY FOR THE NORTH HALF. TONIGHT THROUGH SATURDAY...THE TREND REMAINS THE SAME. UPPER HIGH WILL BUILD WESTWARD ACROSS THE DEEP SOUTH. CONVECTION CHANCES WILL BE LOW(GENERALLY 20%) AND CONFINED PRIMARILY TO THE AFT AND EVE HOURS AND ACROSS THE NORTH. FOR THE SHORT TERM TEMPS...VALUES WILL RUN A FEW DEGREES ABOVE NORMAL. TEMPS INTO THE LOWER 90S FOR TODAY LOOKS LIKELY. UPPER RIDGING DOES APPEAR TO BE A LITTLE MORE PROGRESSIVE IN TERMS OF ITS WESTWARD MOMENT. THEREFORE...TEMPS MAY BACK DOWN A COUPLE DEGREES BY SAT. IN THE EXT FCST...NW FLOW WILL DOMINATE THROUGH THE PERIOD. THE 1ST HALF OF THE EXTENDED...THE FLOW WILL CARRY A SMALL DEGREE OF ANTICYCLONIC CURVATURE. BY THE END OF THE EXT...THE FLOW WILL STRAIGHTEN OUT WITH MORE IN THE WAY OF CURVATURE AND SHEAR UPSTREAM. THUS...POPS WILL BE ON THE INCREASE BY THE END OF THE PERIOD. FOR THE EXT TEMPS...850 MB TEMPS WILL FLIRT WITH 22C FOR MUCH OF THE PERIOD. THIS WILL EQUATE TO ABOVE NORMAL TEMPS(ABOUT 5F OR SO). && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 93 71 91 71 / 20 20 20 20 CLARKSVILLE 90 70 91 70 / 20 20 20 20 CROSSVILLE 89 67 84 66 / 10 20 20 20 COLUMBIA 94 70 93 71 / 10 10 10 10 LAWRENCEBURG 94 70 93 71 / 10 10 10 10 WAVERLY 91 71 92 70 / 20 20 10 10 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1157 PM CDT WED JUL 8 2015 .UPDATE...FOR 06Z AVIATION. && .AVIATION...FOR 06Z TAF DISCUSSION. VFR FLIGHT CATEGORIES. REMOVED THE MVFR VIS OVERNIGHT AT KCKV BUT WILL NEED TO BE LOOKING WESTWARD BY 07-08Z FOR THE POTENTIAL OF A BRIEF SHOWER. WILL LEAVE OUT OF PREVAILING FOR NOW AND AMD AS NECESSARY. A WESTERLY BREEZE WILL PICK UP AGAIN LATE THURSDAY MORNING AND LAST THROUGH THE EARLY EVENING HOURS. MODELS ARE CONSISTENT WITH DROPPING STORMS INTO THE NORTHERN HALF OF THE MID-STATE THURSDAY EVENING. HAVE ADDED IN THE POTENTIAL FOR A TS BY 00Z FRIDAY AT KCKV WITH A VCTS. UNGER && .PREV DISCUSSION... /ISSUED 906 PM CDT WED JUL 8 2015/ UPDATE...HIGH PRESSURE CENTERED TO OUR SOUTHEAST HAS REASSERTED ITSELF TODAY, PUSHING THE FRONTAL SYSTEM TO OUR NORTH AND WEST A BIT FARTHER AWAY, ENABLING DRIER AIR TO ADVECT INTO MIDDLE TENNESSEE AND KEEPING THE RAIN AWAY. EVENING SOUNDING FROM OHX DOES SHOW CONSIDERABLY LESS MOISTURE IN PLACE THIS EVENING, WITH PRECIPITABLE WATER DOWN TO 1.37 INCHES, ALTHOUGH PLENTY OF INSTABILITY REMAINS IN PLACE. MEANWHILE, A 1011 MB LOW IS SITUATED NEAR ST. LOUIS, WITH A WARM FRONT EXTENDING EASTWARD THROUGH THE OHIO VALLEY AND A COLD FRONT RUNNING WEST OF THE MISSISSIPPI RIVER. THERE IS PLENTY OF ACTIVITY OCCURRING IN THE VICINITY OF THE COLD FRONT, AND THE HRRR DOES SHOW SOME OF THIS ACTIVITY SLIPPING INTO WESTERN KY OVERNIGHT. AT THIS TIME, WE ONLY HAVE ISOLATED POP`S IN OUR FAR NW FOR TONIGHT. AM NOT INCLINED TO MAKE ANY CHANGES AT THIS TIME. HOURLY GRIDS SEEM TO BE HOLDING UP WELL. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 27
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1137 PM CDT WED JUL 8 2015 .DISCUSSION... UPDATED FOR 06Z AVIATION DISCUSSION && .PREV DISCUSSION... /ISSUED 1100 PM CDT WED JUL 8 2015/ UPDATE... THE THREAT OF SEVERE WEATHER HAS ENDED ACROSS THE MIDSOUTH FOR TONIGHT. HOWEVER...SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO AFFECT AREAS MAINLY NORTH OF INTERSTATE 40. UPDATED THE HAZARDOUS WEATHER OUTLOOK. MENTIONED THAT A FEW STRONG THUNDERSTORMS ARE POSSIBLE WITH STRONG GUSTY WINDS AND LOCALLY HEAVY RAIN FROM PORTIONS OF NORTHEAST AR...THE MO BOOTHEEL...INTO NORTHWEST TN. WILL HAVE THE UPDATED ZONE FORECASTS AND GRIDS OUT SOON. JCL && PREV DISCUSSION... /ISSUED 541 PM CDT WED JUL 8 2015/ UPDATE... UPDATED THE ZONE FORECASTS AND GRIDS TO INCREASE THE POPS FOR SHOWERS AND THUNDERSTORMS FROM PORTIONS OF NORTHEAST AR...THE MISSOURI BOOTHEEL INTO NORTHWEST TN FOR TONIGHT AND ESPECIALLY THIS EVENING. THE LATEST HRRR AND NAM SHOW CONVECTION ACROSS NORTH CENTRAL AR AHEAD OF A TRAILING COLD FRONT PUSHING EASTWARD INTO THIS AREA. ALSO UPDATED THE HAZARDOUS WEATHER OUTLOOK. A MARGINAL RISK FOR SEVERE THUNDERSTORMS EXISTS ACROSS PORTIONS OF NORTHEAST AR...THE MO BOOTHEEL...AND PORTIONS OF NORTHWEST TN. DAMAGING WIND IS THE MAIN SEVERE WEATHER THREAT BUT AN ISOLATED TORNADO IS ALSO POSSIBLE. HEAVY RAINFALL IS ALSO LIKELY WITH LOCALIZED FLASH FLOODING POSSIBLE. THE ATMOSPHERE ACROSS THIS REGION IS UNSTABLE AND VERY MOIST. SURFACE BASED CAPES ARE BETWEEN 2500 AND 3000 J/KG WITH SURFACE DEW POINTS IN THE MIDDLE AND UPPER 70S. LOW LEVEL SHEAR APPEARS MARGINAL FOR A TORNADO THREAT BUT WITH A SURFACE LOW PASSING TO THE NORTH...LOW LEVEL WINDS MAY BACK ENOUGH FOR AN ISOLATED TORNADO. THE NAM IS THE MORE ROBUST MODEL WITH SHOWING INCREASING 0-1 KM STORM RELATIVE HELICITY AS THE LOW LEVEL WINDS BACK. 0-6 KM BULK SHEAR IS NOT VERY IMPRESSIVE...LIMITING THE SEVERE WEATHER THREAT. NEVERTHELESS...DAMAGING WINDS ARE POSSIBLE WITH BOWING SEGMENTS. JCL && .DISCUSSION... /ISSUED 311 PM CDT WED JUL 8 2015/ MAIN HIGHLIGHT OF THIS FORECAST IS THE TRANSITION BACK TO DRIER/HOTTER WEATHER THROUGH THE WEEKEND... CURRENTLY...WARM AND HUMID CONDITIONS WERE IN PLACE ACROSS THE MIDSOUTH. A SYNOPTIC FRONTAL BOUNDARY ASSOCIATED WITH AN IMPRESSIVE TEMPERATURE GRADIENT FOR EARLY TO MID JULY WAS ANALYZED FROM WEST-CENTRAL MO SOUTHWEST THROUGH NORTH-CENTRAL TX. A SURFACE LOW WAS LOCATED IN WEST-CENTRAL MO WITH AN ATTENDANT WARM FRONT ORIENTED EAST/WEST SOUTH OF I-70. FOR THE REST OF THE AFTERNOON...A FEW SHOWERS AND THUNDERSTORMS REMAIN POSSIBLE WITH THE APPROACH OF THE SYNOPTIC FRONTAL BOUNDARY. SEVERE PARAMETERS REMAIN MARGINAL BUT HI-RES GUIDANCE INDICATES THAT AT LEAST SOME STORM ORGANIZATION COULD OCCUR GIVEN STRONG BUOYANCY SOUTH OF THE WARM FRONT. THE BEST COLLOCATION OF THERMODYNAMICS AND KINEMATICS IS LOCATED ACROSS E MO/SRN IL. SOUTH OF THIS AREA...WIND FIELDS ALOFT DECREASE SIGNIFICANTLY WHICH WILL KEEP ANY SEVERE ACTIVITY ACROSS NORTHERN PORTIONS OF THE MIDSOUTH ISOLATED. HOWEVER...SPORADIC DAMAGING WIND GUSTS ARE POSSIBLE WITH ANY SUSTAINED CONVECTION. THE CHANCE FOR SHOWERS AND A FEW THUNDERSTORMS LASTS THROUGH EARLY THURSDAY MORNING BEFORE FORCING EXITS THE AREA. THURSDAY THROUGH THE WEEKEND...THE MID-SOUTH BEGINS A SLOW WARM UP. 850 MB TEMPERATURES INCREASE INTO THE HIGH TEENS TO NEAR 20 C ON FRIDAY AS RIDGING STRENGTHENS ACROSS THE SOUTHEAST. HIGHS WILL REACH THE LOW 90S ON THURSDAY INCREASING TO THE MID 90S FOR MUCH OF THE REGION DURING THE WEEKEND. HEAT INDICES WILL CLIMB WITH THE TEMPERATURES WITH MOST AREAS EXPECTED TO BE NEAR OR JUST ABOVE 100 THROUGH THIS PERIOD. HEAT ADVISORY CRITERIA IS NOT EXPECTED TO BE REACHED AT THIS TIME...BUT IT WILL STILL BE OPPRESSIVE FOR THOSE WORKING FOR PROLONGED PERIODS OUTDOORS. IN THE LONG-TERM...MODELS DIVERGE SIGNIFICANTLY WITH REGARD TO SMALLER-SCALE PATTERN DETAILS...BUT MOST LONG-TERM GUIDANCE DOES SUGGEST A WEAKENING/FLATTENING OF THE RIDGING PATTERN IN THE SOUTHEAST. THE GFS SUGGESTS THAT A CUTOFF LOW/VORT MAX WILL BECOME DISPLACED FROM THE LARGER HUDSON BAY CIRCULATION BY MID NEXT WEEK. THE ECMWF IS NOT AS AGGRESSIVE WITH CUTTING OFF ENERGY...BUT AGREES THAT A LOWERING OF HEIGHTS WILL OCCUR. THIS SUGGESTS THAT A COOLER/WETTER PERIOD WILL RETURN TO THE MID-SOUTH BUT DETAILS OF SUCH A PATTERN EVOLUTION ARE UNCLEAR AT THIS TIME. TVT && .AVIATION 06Z TAFS VFR THROUGH THE PERIOD...WITH A STRAY SHOWER STILL POSSIBLE AT JBR. SOUTHWEST WINDS WILL AT 5 TO 11 KTS...WITH HIGHER GUSTS AT MEM...JBR AND MKL BY LATE MORNING. WINDS WILL SUBSIDE AROUND 10/01Z. JAB && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1100 PM CDT WED JUL 8 2015 .UPDATE... THE THREAT OF SEVERE WEATHER HAS ENDED ACROSS THE MIDSOUTH FOR TONIGHT. HOWEVER...SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO AFFECT AREAS MAINLY NORTH OF INTERSTATE 40. UPDATED THE HAZARDOUS WEATHER OUTLOOK. MENTIONED THAT A FEW STRONG THUNDERSTORMS ARE POSSIBLE WITH STRONG GUSTY WINDS AND LOCALLY HEAVY RAIN FROM PORTIONS OF NORTHEAST AR...THE MO BOOTHEEL...INTO NORTHWEST TN. WILL HAVE THE UPDATED ZONE FORECASTS AND GRIDS OUT SOON. JCL && .PREV DISCUSSION... /ISSUED 541 PM CDT WED JUL 8 2015/ UPDATE... UPDATED THE ZONE FORECASTS AND GRIDS TO INCREASE THE POPS FOR SHOWERS AND THUNDERSTORMS FROM PORTIONS OF NORTHEAST AR...THE MISSOURI BOOTHEEL INTO NORTHWEST TN FOR TONIGHT AND ESPECIALLY THIS EVENING. THE LATEST HRRR AND NAM SHOW CONVECTION ACROSS NORTH CENTRAL AR AHEAD OF A TRAILING COLD FRONT PUSHING EASTWARD INTO THIS AREA. ALSO UPDATED THE HAZARDOUS WEATHER OUTLOOK. A MARGINAL RISK FOR SEVERE THUNDERSTORMS EXISTS ACROSS PORTIONS OF NORTHEAST AR...THE MO BOOTHEEL...AND PORTIONS OF NORTHWEST TN. DAMAGING WIND IS THE MAIN SEVERE WEATHER THREAT BUT AN ISOLATED TORNADO IS ALSO POSSIBLE. HEAVY RAINFALL IS ALSO LIKELY WITH LOCALIZED FLASH FLOODING POSSIBLE. THE ATMOSPHERE ACROSS THIS REGION IS UNSTABLE AND VERY MOIST. SURFACE BASED CAPES ARE BETWEEN 2500 AND 3000 J/KG WITH SURFACE DEW POINTS IN THE MIDDLE AND UPPER 70S. LOW LEVEL SHEAR APPEARS MARGINAL FOR A TORNADO THREAT BUT WITH A SURFACE LOW PASSING TO THE NORTH...LOW LEVEL WINDS MAY BACK ENOUGH FOR AN ISOLATED TORNADO. THE NAM IS THE MORE ROBUST MODEL WITH SHOWING INCREASING 0-1 KM STORM RELATIVE HELICITY AS THE LOW LEVEL WINDS BACK. 0-6 KM BULK SHEAR IS NOT VERY IMPRESSIVE...LIMITING THE SEVERE WEATHER THREAT. NEVERTHELESS...DAMAGING WINDS ARE POSSIBLE WITH BOWING SEGMENTS. JCL DISCUSSION... /ISSUED 311 PM CDT WED JUL 8 2015/ MAIN HIGHLIGHT OF THIS FORECAST IS THE TRANSITION BACK TO DRIER/HOTTER WEATHER THROUGH THE WEEKEND... CURRENTLY...WARM AND HUMID CONDITIONS WERE IN PLACE ACROSS THE MIDSOUTH. A SYNOPTIC FRONTAL BOUNDARY ASSOCIATED WITH AN IMPRESSIVE TEMPERATURE GRADIENT FOR EARLY TO MID JULY WAS ANALYZED FROM WEST-CENTRAL MO SOUTHWEST THROUGH NORTH-CENTRAL TX. A SURFACE LOW WAS LOCATED IN WEST-CENTRAL MO WITH AN ATTENDANT WARM FRONT ORIENTED EAST/WEST SOUTH OF I-70. FOR THE REST OF THE AFTERNOON...A FEW SHOWERS AND THUNDERSTORMS REMAIN POSSIBLE WITH THE APPROACH OF THE SYNOPTIC FRONTAL BOUNDARY. SEVERE PARAMETERS REMAIN MARGINAL BUT HI-RES GUIDANCE INDICATES THAT AT LEAST SOME STORM ORGANIZATION COULD OCCUR GIVEN STRONG BUOYANCY SOUTH OF THE WARM FRONT. THE BEST COLLOCATION OF THERMODYNAMICS AND KINEMATICS IS LOCATED ACROSS E MO/SRN IL. SOUTH OF THIS AREA...WIND FIELDS ALOFT DECREASE SIGNIFICANTLY WHICH WILL KEEP ANY SEVERE ACTIVITY ACROSS NORTHERN PORTIONS OF THE MIDSOUTH ISOLATED. HOWEVER...SPORADIC DAMAGING WIND GUSTS ARE POSSIBLE WITH ANY SUSTAINED CONVECTION. THE CHANCE FOR SHOWERS AND A FEW THUNDERSTORMS LASTS THROUGH EARLY THURSDAY MORNING BEFORE FORCING EXITS THE AREA. THURSDAY THROUGH THE WEEKEND...THE MID-SOUTH BEGINS A SLOW WARM UP. 850 MB TEMPERATURES INCREASE INTO THE HIGH TEENS TO NEAR 20 C ON FRIDAY AS RIDGING STRENGTHENS ACROSS THE SOUTHEAST. HIGHS WILL REACH THE LOW 90S ON THURSDAY INCREASING TO THE MID 90S FOR MUCH OF THE REGION DURING THE WEEKEND. HEAT INDICES WILL CLIMB WITH THE TEMPERATURES WITH MOST AREAS EXPECTED TO BE NEAR OR JUST ABOVE 100 THROUGH THIS PERIOD. HEAT ADVISORY CRITERIA IS NOT EXPECTED TO BE REACHED AT THIS TIME...BUT IT WILL STILL BE OPPRESSIVE FOR THOSE WORKING FOR PROLONGED PERIODS OUTDOORS. IN THE LONG-TERM...MODELS DIVERGE SIGNIFICANTLY WITH REGARD TO SMALLER-SCALE PATTERN DETAILS...BUT MOST LONG-TERM GUIDANCE DOES SUGGEST A WEAKENING/FLATTENING OF THE RIDGING PATTERN IN THE SOUTHEAST. THE GFS SUGGESTS THAT A CUTOFF LOW/VORT MAX WILL BECOME DISPLACED FROM THE LARGER HUDSON BAY CIRCULATION BY MID NEXT WEEK. THE ECMWF IS NOT AS AGGRESSIVE WITH CUTTING OFF ENERGY...BUT AGREES THAT A LOWERING OF HEIGHTS WILL OCCUR. THIS SUGGESTS THAT A COOLER/WETTER PERIOD WILL RETURN TO THE MID-SOUTH BUT DETAILS OF SUCH A PATTERN EVOLUTION ARE UNCLEAR AT THIS TIME. TVT && .AVIATION... 00Z TAF CYCLE WITH THE EXCEPTION OF TUP GUSTY SOUTH TO SOUTHWEST WINDS WILL BE THE MAIN AVIATION NUISANCE THROUGH THE PERIOD...WITH A SMALL WINDOW NEAR SUNRISE WHEN WINDS WILL SUBSIDE. BROKEN LINE OF T-STORMS OVER CENTRAL ARKANSAS WILL MOVE NORTHEAST THIS EVENING SKIRTING JBR...OTHERWISE THE TAF SITES WILL BE DRY AND VFR. JAB && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
614 PM CDT FRI JUL 10 2015 .AVIATION... UPPER LEVEL HIGH PRESSURE WILL CONTINUE TO DOMINATED NORTH TEXAS AIRSPACE THROUGH SATURDAY AND KEEP GENERALLY VFR CONDITIONS AND GOOD FLYING WEATHER. THE ONLY EXCEPTION MAY BE SOME VERY BRIEF MVFR CEILINGS IN WACO JUST AFTER SUNRISE AS A 25 KNOT LOW LEVEL JET BRINGS SLIGHTLY DEEPER LOW LEVEL MOISTURE NORTHWARD. IF ANY MVFR CEILINGS DO DEVELOP IN WACO THEY WILL LIFT AND SCATTER BY 16Z SATURDAY. A SOUTH WIND WILL PREVAIL AT ALL TAF SITES THROUGH SATURDAY AFTERNOON BETWEEN 7 AND 13 KNOTS. 79 && .PREV DISCUSSION... /ISSUED 326 PM CDT FRI JUL 10 2015/ AT MID AFTERNOON...AN UPPER LEVEL RIDGE EXTENDED FROM SOUTHEAST GEORGIA WESTWARD INTO CENTRAL TEXAS. THIS RIDGE WILL BUILD WESTWARD ACROSS TEXAS THROUGH EARLY NEXT WEEK. THIS WILL RESULT IN GENERALLY RAIN-FREE WEATHER AND A RISE IN AFTERNOON HIGH TEMPERATURES THROUGH TUESDAY. SOME LOW CLOUDS MAY WORK THEIR WAY INTO THE SOUTHERN COUNTIES AROUND DAYBREAK THROUGH MID MORNING FOR THE NEXT COUPLE OF DAYS...BUT OVERALL EXPECT MOSTLY SUNNY DAYS AND MOSTLY CLEAR NIGHTS THROUGH EARLY NEXT WEEK. ISOLATED SHOWERS AND THUNDERSTORMS FORMED OVER EXTREME SOUTHEAST TEXAS TODAY. THIS ACTIVITY WILL DISSIPATE BY SUNSET TO THE SOUTHEAST OF THE FORECAST AREA. THE NAM AND HRRR TRY TO SHOW A FEW CELLS MOVING INTO THE EXTREME SOUTHEAST ZONES THIS EVENING...BUT WILL JUST LEAVE 10 PERCENT POPS WITH NO WEATHER MENTIONED. A FEW STORMS ARE POSSIBLE AGAIN OVER THE WEEKEND ACROSS SOUTHEAST TEXAS BUT THIS ACTIVITY SHOULD DISSIPATE AROUND SUNSET BEFORE REACHING THE SOUTHEASTERN ZONES. THE UPPER LEVEL RIDGE WILL START TO WEAKEN BY TUESDAY. THIS MAY ALLOW AFTERNOON HIGHS TO DECREASE BY A COUPLE OF DEGREES BUT GENERALLY DRY WEATHER WILL PREVAIL. THE ONLY EXCEPTION MAY BE SOME SEABREEZE ACTIVITY WEDNESDAY THROUGH FRIDAY. HAVE INCLUDED SOME 20 PERCENT POPS ACROSS THE EXTREME SOUTHEAST FRIDAY AFTERNOON. 58 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 75 94 76 96 77 / 5 5 5 5 5 WACO, TX 73 94 74 96 75 / 5 5 5 5 5 PARIS, TX 73 92 73 93 74 / 5 5 5 5 5 DENTON, TX 72 94 74 95 75 / 5 5 5 5 5 MCKINNEY, TX 74 93 74 95 75 / 5 5 5 5 5 DALLAS, TX 76 95 77 96 78 / 5 5 5 5 5 TERRELL, TX 74 93 74 95 75 / 5 5 5 5 5 CORSICANA, TX 76 93 74 94 75 / 5 5 5 5 5 TEMPLE, TX 72 93 73 95 73 / 5 5 5 5 5 MINERAL WELLS, TX 72 93 73 95 73 / 5 5 5 5 5 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 79/75
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1222 PM CDT Thu Jul 9 2015 .UPDATE... Updated forecast to include a slight chance of thunderstorms across all of the Big Country this afternoon. && .DISCUSSION... Thunderstorm outflow boundary moving slowly south along a Roby... Stamford...Woodson line at Noon will be focus for isolated thunderstorm development this afternoon. && .AVIATION... /18Z TAFS/ Lee trough will bring gusty south winds this afternoon and again Friday beginning mid morning. Winds gusts between 20 and 25 KTS expected. MVFR stratus will return towards morning Friday, scattering out mid morning. && .PREV DISCUSSION... /ISSUED 644 AM CDT Thu Jul 9 2015/ AVIATION... /12Z TAFS/ Currently seeing MVFR stratus across the southern terminals and this should persist through the mid morning hours before scattering out to VFR. South winds will increase 15 to 20 kt today, diminishing by sunset. Stratus is expected to develop across towards daybreak Friday, with MVFR ceilings returning to the southern terminals after 09Z. PREV DISCUSSION... /ISSUED 353 AM CDT Thu Jul 9 2015/ SHORT TERM... (Today and Tonight) The subtropical ridge over the southeast states will begin to build west into Texas the next 24 hours, and will be the main weather feature affecting our weather through tonight. A large area of showers and thunderstorms is currently moving east-southeast across the Texas Panhandle and far northwest Texas early this morning. This activity will track east along the Red River Valley through the morning hours, with the majority of the precipitation remaining north of the area. The HRRR however, does generate some QPF across Haskell and Throckmorton counties this morning. Cannot rule this out so have added slight POPs to the forecast for both counties this morning. Otherwise, morning cloud cover will give way to partly cloudy skies this afternoon, with highs around 90 degrees. We`ll see some stratus redevelop late tonight across southern sections, with overnight lows around 70 degrees. LONG TERM... (Friday through next Wednesday) On Friday, an upper level ridge across the Southeast United States will continue to build west toward West Central Texas. In the meantime, daytime heating should allow for the development of scattered showers and thunderstorms across West Texas. The 00z NAM is the most aggressive with this scenario, which drifts the convection east, toward our western counties. Whether any of this convection makes it into our western counties will be dependent on the strength of the developing ridge, but for now the forecast was kept dry. Highs on Friday will be below seasonal normals, generally in the lower 90s. A much quieter weather pattern is expected this weekend through much of next week as an upper level ridge dominates the weather. Temperatures will slowly creep up each day, although plentiful soil moisture should help to keep temperatures a few degrees below MOS guidance. High temperatures for the first part of next week will generally be in the mid to upper 90s, although a few locations may reach the century mark. No rain is forecast through the end of the week. && .PRELIMINARY POINT TEMPS/POPS... Abilene 90 70 91 71 91 / 20 0 5 0 0 San Angelo 91 70 92 71 92 / 5 5 5 5 0 Junction 91 70 90 70 90 / 0 0 5 0 0 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99/04
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
644 AM CDT Thu Jul 9 2015 .AVIATION... /12Z TAFS/ Currently seeing MVFR stratus across the southern terminals and this should persist through the mid morning hours before scattering out to VFR. South winds will increase 15 to 20 kt today, diminishing by sunset. Stratus is expected to develop across towards daybreak Friday, with MVFR ceilings returning to the southern terminals after 09Z. && .PREV DISCUSSION... /ISSUED 353 AM CDT Thu Jul 9 2015/ SHORT TERM... (Today and Tonight) The subtropical ridge over the southeast states will begin to build west into Texas the next 24 hours, and will be the main weather feature affecting our weather through tonight. A large area of showers and thunderstorms is currently moving east-southeast across the Texas Panhandle and far northwest Texas early this morning. This activity will track east along the Red River Valley through the morning hours, with the majority of the precipitation remaining north of the area. The HRRR however, does generate some QPF across Haskell and Throckmorton counties this morning. Cannot rule this out so have added slight POPs to the forecast for both counties this morning. Otherwise, morning cloud cover will give way to partly cloudy skies this afternoon, with highs around 90 degrees. We`ll see some stratus redevelop late tonight across southern sections, with overnight lows around 70 degrees. LONG TERM... (Friday through next Wednesday) On Friday, an upper level ridge across the Southeast United States will continue to build west toward West Central Texas. In the meantime, daytime heating should allow for the development of scattered showers and thunderstorms across West Texas. The 00z NAM is the most aggressive with this scenario, which drifts the convection east, toward our western counties. Whether any of this convection makes it into our western counties will be dependent on the strength of the developing ridge, but for now the forecast was kept dry. Highs on Friday will be below seasonal normals, generally in the lower 90s. A much quieter weather pattern is expected this weekend through much of next week as an upper level ridge dominates the weather. Temperatures will slowly creep up each day, although plentiful soil moisture should help to keep temperatures a few degrees below MOS guidance. High temperatures for the first part of next week will generally be in the mid to upper 90s, although a few locations may reach the century mark. No rain is forecast through the end of the week. && .PRELIMINARY POINT TEMPS/POPS... Abilene 90 70 91 71 91 / 5 0 5 0 0 San Angelo 91 70 92 71 92 / 5 5 5 5 0 Junction 91 70 90 70 90 / 5 0 5 0 0 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99/24
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
353 AM CDT Thu Jul 9 2015 .SHORT TERM... (Today and Tonight) The subtropical ridge over the southeast states will begin to build west into Texas the next 24 hours, and will be the main weather feature affecting our weather through tonight. A large area of showers and thunderstorms is currently moving east-southeast across the Texas Panhandle and far northwest Texas early this morning. This activity will track east along the Red River Valley through the morning hours, with the majority of the precipitation remaining north of the area. The HRRR however, does generate some QPF across Haskell and Throckmorton counties this morning. Cannot rule this out so have added slight POPs to the forecast for both counties this morning. Otherwise, morning cloud cover will give way to partly cloudy skies this afternoon, with highs around 90 degrees. We`ll see some stratus redevelop late tonight across southern sections, with overnight lows around 70 degrees. .LONG TERM... (Friday through next Wednesday) On Friday, an upper level ridge across the Southeast United States will continue to build west toward West Central Texas. In the meantime, daytime heating should allow for the development of scattered showers and thunderstorms across West Texas. The 00z NAM is the most aggressive with this scenario, which drifts the convection east, toward our western counties. Whether any of this convection makes it into our western counties will be dependent on the strength of the developing ridge, but for now the forecast was kept dry. Highs on Friday will be below seasonal normals, generally in the lower 90s. A much quieter weather pattern is expected this weekend through much of next week as an upper level ridge dominates the weather. Temperatures will slowly creep up each day, although plentiful soil moisture should help to keep temperatures a few degrees below MOS guidance. High temperatures for the first part of next week will generally be in the mid to upper 90s, although a few locations may reach the century mark. No rain is forecast through the end of the week. && .PRELIMINARY POINT TEMPS/POPS... Abilene 90 70 91 71 91 / 5 0 5 0 0 San Angelo 91 70 92 71 92 / 5 5 5 5 0 Junction 91 70 90 70 90 / 5 0 5 0 0 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ JW/Daniels
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1134 PM CDT WED JUL 8 2015 .AVIATION... /6Z TAFS/ VFR CONDITIONS PREVAIL ACROSS NORTH TEXAS TONIGHT ALTHOUGH SCT/BKN HIGH LEVEL CLOUDS WILL PERSIST FOR ANOTHER SEVERAL HOURS. SOUTHERLY WINDS WILL STRENGTHEN OVERNIGHT WITH MVFR STRATUS EXPECTED TO DEVELOP AND SPREAD NORTH. FOR NOW...WILL MAINTAIN THE TEMPO BKN MVFR CIGS IN THE METROPLEX DURING THE EARLY MORNING HOURS WITH VFR CONDITIONS EXPECTED BY MIDDAY. NO SIGNIFICANT CHANGES WERE MADE TO THE CURRENT FORECAST. DUNN && .PREV DISCUSSION... /ISSUED 211 PM CDT WED JUL 8 2015/ IN THE MID LEVELS THERE IS A SHORTWAVE TO THE NORTHWEST OF THE AREA...THAT REACHES AS FAR SOUTH AS THE TEXAS PANHANDLE. THE MAIN CONCERN FOR TODAY IS WHATS LEFT OF A FRONT THAT IS CURRENTLY LOCATED AT A LINE FROM GRAYSON COUNTY...THROUGH DENTON COUNTY TO PARKER AND EARTH COUNTIES...THEN DOWN INTO COMANCHE COUNTY. THIS FEATURE WILL ALLOW FOR LOW LEVEL CONVERGENCE. THERE IS SOME SUBSIDENCE TAKING OVER FOR THE FAR NORTHWEST COUNTIES...SO POPS HAVE BEEN LOWERED FOR THAT AREA. WHERE THIS FRONT MOVES WILL DETERMINE WHICH AREAS WILL BE THE MOST SUSCEPTIBLE TO FLASH FLOODING. WHERE THE SOUTHERN EXTENT OF THE FRONT TRACKS WILL BE THE MOST CONCERNING. THE HRRR AND NAM HAVE BEEN DOING THE BEST WITH THIS FEATURE...THEY BOTH HAVE IT TRACKING EAST AND THEN LIFTING TO THE NORTH THROUGH THIS EVENING. THE CONVECTION HAS ALREADY STARTED TO FALL APART AT THIS POINT IN THE AFTERNOON...ALLOWING FOR LIGHTER ACCUMULATIONS. DUE TO WET CONDITIONS AND THE ADDITIONAL LIGHT ACCUMULATIONS THE FLASH FLOOD WATCH WILL CONTINUE THROUGH 22Z...WITH THE FAR NORTHWEST COUNTIES REMOVED. BY THURSDAY A MORE TYPICAL SUMMER TIME PATTERN WILL RETURN WITH UPPER LEVEL RIDGING STARTING TO BUILD BACK IN...AND CONTINUE TO BUILD THROUGH EARLY NEXT WEEK. THE FORECAST IS DRY DURING THAT TIME...WITH A WARMING TEMPERATURE TREND. WINDS WILL GENERALLY BE SOUTHERLY AT 10 TO 15 MPH. THEREFORE, THE TEMPERATURES WILL BE THE BIGGEST CHALLENGE FOR THE NEXT WEEK. SOMETIME EARLY NEXT WEEK WE MIGHT START TO SEE SOME OF THE FIRST 100 DEGREE TEMPERATURES THIS YEAR ACROSS PARTS OF THE AREA. THE LONG RANGE MODELS HINT AT SOME CONVECTION IN THE MIDDLE OF NEXT WEEK...BUT HAVE KEEP WEATHER OUT OF FORECAST AT THIS TIME DUE TO LACK OF CONFIDENCE OF TIMING. 78.JG && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 76 93 76 94 76 / 10 5 0 0 0 WACO, TX 74 92 73 93 74 / 5 5 0 0 0 PARIS, TX 72 91 73 93 73 / 10 5 0 0 0 DENTON, TX 74 91 72 94 72 / 10 5 0 0 0 MCKINNEY, TX 75 93 74 92 74 / 10 5 0 0 0 DALLAS, TX 76 93 77 95 78 / 10 5 0 0 0 TERRELL, TX 74 91 74 93 74 / 5 5 0 0 0 CORSICANA, TX 75 91 75 93 74 / 5 5 0 0 0 TEMPLE, TX 72 91 72 92 72 / 5 5 0 0 0 MINERAL WELLS, TX 71 90 71 91 71 / 10 5 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
134 AM EDT THU JUL 9 2015 .SYNOPSIS... OUR AREA WILL STAY UNDER AN INCREASING UPPER RIDGE OVER THE SOUTHEAST THROUGH THE END OF THE WEEK. A FRONTAL BOUNDARY WILL STALL NORTH OF OUR AREA TONIGHT AND SHIFT NORTH INTO THE OHIO/PA AREA BY THURSDAY. BY THIS WEEKEND THE UPPER RIDGES HEADS WEST ALLOWING A BACKDOOR FRONT TO MOVE INTO THE VIRGINIAS. && .NEAR TERM /THROUGH TODAY/... AS OF 1115 PM EDT WEDNESDAY... ADJUSTED POPS TO REFLECT CURRENT RADAR TRENDS. LARGE AREA OF LIGHT RAIN DRIFTING ACROSS AREAS MAINLY EAST OF THE BLUE RIDGE NOW. UPSTREAM ACTIVITY HAS DIMINISHED...AND ONLY SOME VERY MEAGER ACTIVITY IN SOUTHERN OH. HRRR SHOWS LITTLE TO NO ACTIVITY OVERNIGHT. HAVE TAPERED POPS FROM LIKELY IN AREAS WHERE RAIN IS OCCURRING NOW TO BELOW MENTIONABLE BY 06Z...EXCEPT IN THE FAR WEST WHERE A LINGER SMALL CHANCE OF -SHRA CONTINUES OVERNIGHT. TEMPS LOOKED TOO COOL BASED ON CURRENT READINGS STILL IN THE MID TO UPPER 70S ACROSS THE PIEDMONT AND DEWPOINTS 68 TO 74 ACROSS MUCH OF THE CWA. AS OF 1000 PM EDT WEDNESDAY... FLASH FLOOD WATCH CANCELLED. SEVERE STORM THREAT ACROSS THE PIEDMONT REMOVED BY SPC. ONLY LIGHT RAIN TRACKING ACROSS THE CWA AT THIS TIME...AND LITTLE DEVELOPMENT EXPECTED OVERNIGHT. EXTENSIVE CLOUD COVER LIMITED HEATING TODAY. EVENING SOUNDING SHOWED 500MB TEMP OF -5C...QUITE WARM TO SUPPORT MUCH CONVECTION. FRONTAL BOUNDARY WILL DRIFT NORTH OVERNIGHT...SO MAIN FOCUS FOR NIGHTTIME ACTIVITY SHOULD REMAIN FURTHER NORTH INTO NORTHERN VA/WV/MD. FOCUS WILL NOW TURN TO THURSDAY AFTERNOON WHEN THE FRONTAL BOUNDARY SHOULD MAKE A MOVE BACK TO THE SOUTH IN ASSOCIATION WITH A WEAK SHORT WAVE. THIS APPEARS TO BE A LATE DAY/EVENING EVENT. SPC HAS A MARGINAL RISK NEAR THE I-64 CORRIDOR WITH A SLIGHT RISK UP IN THE LWX AREA. OVERALL...WOULD EXPECT TOMORROW TO PRESENT A MORE SIGNIFICANT THREAT FOR ACTIVE WEATHER THAN TODAY...BUT IT MAY BE A LATE DAY EVENT...WITH NOT MUCH DURING THE AFTERNOON. NO MAJOR CHANGES TO THE GRIDS AT THIS TIME. AS OF 730 PM EDT WEDNESDAY... EVALUATING FLOOD THREAT AND SEVERE WEATHER THREAT OVER THE NEXT FEW HOURS. WITH RESPECT TO SEVERE THREAT...PIEDMONT REMAINS QUITE UNSTABLE WITH CAPES 1500-2500 J/KG IN THAT AREA. HOWEVER...PERSISTENT CLOUD COVER NOT HELPING WITH CONVECTIVE DEVELOPMENT AND SO FAR THERE HAS BASICALLY BEEN NOTHING ACROSS THE AREA...THE EXTREME EASTERN PART OF WHICH IS IN A MARGINAL RISK. ONLY CONCERN WOULD BE WHETHER OR NOT OUTFLOW FROM DISSIPATING ACTIVITY IN THE NEW RIVER VALLEY WILL REACH THIS AREA AND SPARK OFF NEW CONVECTION IN THE NEXT COUPLE OF HOURS. PROBABILITY FOR THIS TO OCCUR SEEMS LOW AT THIS POINT...BUT NOTING ACTIVITY DOWN TOWARD KRDU/KGSO...IT SEEMS STILL POSSIBLE. WILL COORDINATE WITH SPC AND IF FEELING IS THAT SEVERE IS UNLIKELY AT THIS POINT...WILL REMOVE FROM THIS THREAT FROM THE HWO. WITH RESPECT TO THE FLOOD THREAT AND THE ONGOING FLASH FLOOD WATCH...WILL LEAVE AS IS SINCE IT ONLY HAS A LITTLE OVER TWO HOURS LEFT. TO THIS POINT...RAINFALL HAS BEEN SPOTTY AND MAINLY ACROSS THE SOUTHERN PART OF THE FFA. WATCHING AREA OF MORE WIDESPREAD RAIN AND ISOLATED THUNDER SPREADING TOWARD THE WV COUNTIES FROM RALEIGH/FAYETTE/NICHOLAS COUNTY AREA. WILL LEAVE AS IS FOR NOW...BUT IF THIS DOES NOT MATERIALIZE...WILL LIKELY CANCEL FFA EARLY. MADE SOME MINOR ADJUSTMENTS TO TEMPS/POPS...BUT NO SIGNIFICANT CHANGES AT THIS TIME. AS OF 300 PM EDT WEDNESDAY... ELECTED TO POST A FLASH FLOOD WATCH FOR THE NORTHWEST UNTIL 10 PM WITH LOW FFG AND POTENTIAL CONVECTION WITH HEAVY RAINS. FRONTAL BOUNDARY WITH WAVES OF LOW PRESSURE HAS STALLED TO OUR NORTH ALONG THE OHIO RIVER THIS AFTERNOON. CONVECTION THIS AFTERNOON HAS BEEN HINDERED BY THE HEAVY CLOUD COVER ACROSS THE REGION LIMITING INSTABILITY. THERE ARE SOME BREAKS IN THE CLOUDS AND MORE SUNSHINE TO OUR SOUTHWEST ACROSS THE TENNESSEE VALLEY. EXPECTED TO SEE ADDITIONAL CONVECTION DEVELOPED AND INCREASE IN COVERAGE TO OUR SOUTHWEST ACROSS KENTUCKY AND TENNESSEE IN THE UNSTABLE MOIST AIR WITH CAPES 2 TO 3K J/KG AND LIS FROM MINUS 3 TO MINUS 5. THESE STORMS WILL MOVE EAST INTO WESTERN PORTIONS OF THE FORECAST AREA. MOISTURE TRANSPORT INCREASES THIS AFTERNOON INTO TONIGHT FROM THE WEST. STORM MOTION SHOULD BE FROM WEST SOUTHWEST AROUND 30 KTS. WPC HAS US A SLICE OF SOUTHEAST WEST VIRGINIA INTO BATH COUNTY VA IN SLIGHT RISK OF EXCEEDING FLASH FLOOD GUIDANCE...WITH VERY LOW 1 TO 3 HOUR FFG. SATURATED GROUND AND ELEVATED CREEK LEVELS IN SOME LOCATIONS COULD RESULT IN FLOODING PROBLEMS. NOT EXPECTING ANY WIDESPREAD SEVERE THREAT WITH THIS AFTERNOON AND EVENING CONVECTION WITH THE DAY ONE CONVECTIVE OUTLOOK KEEPING OUR AREA IN GENERAL. SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A SHORTWAVE SHOULD MOVE OUT OF THE FORECAST AREA THIS EVENING INTO TONIGHT...WITH CLEARING TAKING PLACE FROM SOUTH TO NORTH OVERNIGHT. 12Z MODELS KEEP THE MAIN ENERGY AND AREA OF RAIN ALONG FRONTAL BOUNDARY IN OHIO AND NORTHERN KENTUCKY THROUGH WESTERN PENNSYLVANIA LATER TONIGHT...WITH MORE SCATTERED CONVECTION FOR US TONIGHT. ADDED FOG TO ISC GRIDS OVERNIGHT GIVEN SOME CLEARING...LIGHT WINDS AND MOISTURE IN THE LOW LEVELS. LOW TEMPERATURES OVERNIGHT WILL RANGE FROM THE LOWER 60S IN THE NORTHWEST MOUNTAINS TO THE LOWER 70S IN THE PIEDMONT. FRONTAL BOUNDARY WILL MOVE NORTH OF THE REGION LATE TONIGHT AND THURSDAY...AS LOW PRESSURE MOVES NORTHEAST TOWARDS THE GREAT LAKES REGION. BEING SOUTH OF THE FRONT...SOUTHWESTERLY FLOW AND SOME SUNSHINE EXPECTED THURSDAY. SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP THURSDAY AFTERNOON. PLAYED POPS CLOSER TO GFS WITH HIGHEST POPS IN THE NORTHWEST PORTION OF FORECAST AND TAPERING OFF AS ONE HEADS SOUTHEAST. SPC DAY 2 CONVECTIVE OUTLOOK HAS PUSH THE MARGINAL POTENTIAL INTO NORTH PORTIONS OF FORECAST AREA. THE MAIN THREAT WILL BE FOR GUSTY WINDS AND HAIL. HIGHS TEMPERATURES THURSDAY WILL CLIMB INTO THE MID 70S IN THE NORTHWEST MOUNTAINS TO THE LOWER AND MID 90S IN THE PIEDMONT. && .SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/... AS OF 330 PM EDT WEDNESDAY... SUBTROPICAL RIDGE OF HIGH PRESSURE WILL BE CENTERED JUST SOUTH OF THE REGION FRIDAY...THEN RETROGRADE WEST TOWARD THE SOUTH CENTRAL CONUS THIS WEEKEND...HEIGHTS FALLING ACROSS THE MID ATLANTIC. THIS WILL ALLOW THE SURFACE FRONT WHICH HAS BEEN WAVERING AROUND ACROSS THE OHIO VALLEY AND NORTHERN MID ATLANTIC...TO SINK SOUTH ACROSS OUR REGION FOR THE WEEKEND. CONVERGENCE ALONG THE FRONT WILL SUPPORT A DAILY THREAT FOR SHOWERS/STORMS...BUT FAVORING THE WESTERN CWA FOR THE HIGHEST POPS. WITH NORTHWEST FLOW DEVELOPING ALOFT...ANY ACTIVITY THAT DEVELOPS UPSTREAM TOWARD THE OHIO VALLEY WILL MOVE DOWNSTREAM INTO THE WESTERN SLOPES OF OUR FORECAST AREA. WITH THE FRONT FORECAST TO BECOME HUNG-UP OVER OR JUST SOUTH OF THE AREA THIS WEEKEND...CLOUD COVER WILL PREVENT TEMPERATURES FROM WARMING MUCH ABOVE THE SEASONAL NORM. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 330 PM EDT WEDNESDAY... MODELS ARE IN AGREEMENT THE SUBTROPICAL RIDGE WILL CONTINUE TO RETROGRADE WESTWARD...EXPANDING INTO THE ROCKIES FOR NEXT WEEK...JULY 13-17. SHORT WAVE ENERGY PASSING DOWNSTREAM FROM THIS RIDGE IS THEN EXPECTED TO CARVE OUT AN EASTERN CONUS TROUGH OF LOW PRESSURE...WITH DIFFERING SOLUTIONS WITH RESPECT TO STRENGTH. THE GFS IS THE MOST AMPLIFIED OF THE SOLUTIONS...ENTERTAINING A CUTOFF LOW DEVELOPING OFF THE TAIL END OF THE TROUGH VCNTY OF THE TENNESSEE VALLEY. THE ECMWF IS LESS AMPLIFIED...ITS RUN TO RUN SOLUTIONS RANGING FROM A CUTOFF LOW OVER THE GREAT LAKES VS NO CUTOFF SOLUTION AT ALL. ALL THINGS CONSIDERED...AT THE VERY LEAST WE WILL BE UNDER THE INFLUENCE OF A TROUGH FOR MOST OF NEXT WEEK...AN ACTIVE FRONTAL ZONE REMAINING CLOSE...IF NOT ALIGNED DIRECTLY OVER THE FORECAST AREA. THIS SUGGESTS A DAILY THREAT FOR SHOWERS/STORMS...BUT WITH LITTLE CONFIDENCE ON DETAILS WITH RESPECT TO TIMING/PATH OF DEEP CONVECTION. AS SUCH LONG TERM FORECAST REFLECTS A SHOTGUN STANCE FOR POPS...ALTHOUGH FAVORED THE PEAK HEATING OF THE DIURNAL CYCLE FOR GREATEST POPS/THUNDER COINCIDENT WITH PEAK INSTABILITY. TEMPERATURES SHOULD BE NEAR THE SEASONAL NORMS...ALTHOUGH WOULD FAVOR SOMETHING JUST BELOW NORMAL FOR THE MIDDLE OF NEXT WEEK IF THE CUTOFF LOW DEVELOPS CLOSER TO THE CENTRAL APPALACHIANS. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... AS OF 125 AM EDT THURSDAY... PROBABILITY OF FOG INCREASING OVER THE MOUNTAIN VALLEYS AS HIGH CLOUDS EXPECTED TO THIN OUT. MODELS ARE NOT HITTING IT TOO HARD BUT HAVE TEMPO FOR DENSE FOG AT LWB...WHILE BCB MAY HIT IFR AT TIMES BETWEEN 09-12Z. A LITTLE FOG AT DANVILLE WILL OCCUR ALSO BUT EXPECT ONLY MVFR AT TIMES BETWEEN 09-13Z. THURSDAY DURING THE DAY WILL BE VFR WITH ONLY ISOLATED CONVECTION EXPECTED LATE IN THE DAY NORTH OF A BLF-LYH LINE...BUT THE LATEST MODELS HOLD OFF ON ANY THREAT UNTIL LATE EVENING...AND EVEN THEN IT IS LOW...EXCEPT PERHAPS LWB. EXTENDED AVIATION DISCUSSION... OUR REGION WILL REMAIN ON THE WARM/MOIST SIDE...SUBJECT TO DAILY THREAT FOR MVFR SHOWERS/STORMS THROUGH SUNDAY. OTRW EXPECTING PATCHY LATE NIGHT/EARLY MORNING LOW CLOUDS/FOG WITH IFR-LIFR CIGS/VSBYS. OVERALL...CONDITIONS SHOULD IMPROVE TO MVFR- VFR OUTSIDE OF ANY SHRA/TSRA ACTIVITY DURING THE AFTERNOONS. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...KK NEAR TERM...KK/RAB SHORT TERM...PM LONG TERM...PM AVIATION...DS/WP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
319 PM CDT THU JUL 9 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 319 PM CDT THU JUL 9 2015 LATEST WATER VAPOR SATELLITE IMAGERY SHOWS WEST TO EAST ZONAL FLOW ACROSS THE WESTERN CANADA PROVINCES...UPPER LEVEL TROUGH OVER THE NORTHERN GREAT LAKES REGION AND CLOSED UPPER LEVEL LOW OVER THE WEST COAST. LATEST 19Z SURFACE ANALYSIS INDICATES HIGH PRESSURE OVER IOWA...ILLINOIS AND SOUTHERN WISCONSIN. MAIN FORECAST CONCERN IS FOG POTENTIAL IN RIVER VALLEYS AND PARTS OF CENTRAL WISCONSIN TONIGHT. THE 09.12Z NAM AND 09.15Z RAP BUFKIT SOUNDINGS SHOW INVERSION DEVELOPING AND WINDS LESS THAN 10 KNOTS THROUGH 5000 FEET TONIGHT. EXPECT PATCHY TO AREAS OF FOG TO DEVELOP IN THE RIVER VALLEYS AND PARTS OF CENTRAL WISCONSIN AFTER 07Z FRIDAY. SURFACE RIDGE REMAINS IN CONTROL OF THE AREA FRIDAY AND SUBSIDENCE UNDERNEATH RIDGE WILL ALLOW FOR DRY WEATHER ACROSS THE FORECAST AREA. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 319 PM CDT THU JUL 9 2015 FOCUS TURNS TO PRECIPITATION CHANCES FRIDAY NIGHT INTO SUNDAY. THE 09.12Z GFS/NAM/ECMWF ARE SHOWING A SLOWER PROGRESSION AND SLIGHTLY FARTHER SOUTH PLACEMENT OF FIRST IMPULSE LIFTING NORTH INTO THE GREAT LAKES REGION PER DPROG/DT. THE 09.12Z GFS/ECMWF/NAM INDICATE UPPER LEVEL RIDGE AMPLIFIES OVER THE CENTRAL UNITED STATES DURING THE PERIOD AND EJECT PIECES OF ENERGY OUT OF THE CLOSED UPPER LEVEL LOW OVER THE WESTERN UNITED STATES INTO THE UPPER MIDWEST AND GREAT LAKES REGION. FIRST IMPULSE TO IMPACT PARTS OF THE FORECAST AREA SATURDAY...THE 09.12Z GFS/NAM/ECMWF SHOW PV ADVECTION/LIFT/MOISTURE CONVERGENCE IN ASSOCIATION WITH THE IMPULSE AND FOCUS THE BETTER MOISTURE CONVERGENCE ACROSS THE SOUTHERN PORTIONS OF THE FORECAST AREA. BASED ON THE SLOWER PROGRESSION AND SLIGHTLY FARTHER SOUTH PLACEMENT OF THE MOISTURE CONVERGENCE/LIFT...PER DPROG/DT...HAVE REDUCED PRECIPITATION CHANCES ACROSS THE SOUTHERN PORTIONS OF THE FORECAST AREA FRIDAY NIGHT AND HAVE CONFINED THE HIGHER SHOWER/THUNDERSTORM CHANCES ACROSS THE SOUTHERN PORTIONS OF THE FORECAST AREA INTO SATURDAY AND SATURDAY NIGHT. THE 09.12Z GFS/NAM SUGGEST BETTER INSTABILITY AND DEEPER SHEAR WITH THE IMPULSE TO BE SOUTH OF THE FORECAST AREA SATURDAY INTO SATURDAY NIGHT. AT THIS TIME...NOT EXPECTING ANY SEVERE THUNDERSTORMS ACROSS THE SOUTHERN FORECAST AREA. THE 09.12Z GFS/NAM SHOW INCREASING PRECIPITABLE WATER VALUES OF 1.5 TO 2 INCHES ACROSS THE SOUTHERN PART OF THE FORECAST AREA SATURDAY...THUNDERSTORMS WILL BE EFFECIENT RAIN PRODUCERS...HOWEVER THE PROGRESSION OF THE THUNDERSTORMS/IMPULSE WOULD ALLOW FOR BRIEF HEAVY RAINS AT ONE PARTICULAR LOCATION. SUNDAY...IMPULSE MOVES EAST OF THE FORECAST AREA AND SUBSIDENCE BEHIND IMPULSE WILL ADVECT DRIER AIR INTO THE WESTERN PART OF THE FORECAST AREA. THE 09.12Z GFS/NAM/ECMWF INDICATE DIFFERENCES ON HOW QUICKLY THE IMPULSE PUSHES EAST OF THE FORECAST AREA...AS THE NAM APPEARS TO BE SLIGHTLY SLOWER AND MORE ROBUST WITH RETURN SOUTHERLY FLOW/MOISTURE CONVERGENCE ACROSS THE EASTERN PART OF THE FORECAST AREA. HAVE CONFINED THE HIGH PRECIPITATION CHANCES ACROSS THE EASTERN HALF OF THE FORECAST AREA SUNDAY. MAIN FORECAST CONCERNS SUNDAY NIGHT THROUGH THURSDAY ARE PRECIPITATION CHANCES THROUGH THE PERIOD. THE 09.12Z GFS/GEM/ECMWF ARE IN DECENT AGREEMENT IN DIGGING UPPER LEVEL TROUGH OVER THE EASTERN UNITED STATES AND DEVELOP WEST TO NORTHWEST FLOW ALOFT ACROSS THE NORTHERN PLAINS AND GREAT LAKES REGION THROUGH WEDNESDAY. THEN...THE 09.12Z GFS/ECMWF DIVERGE...WHERE THE 09.12Z GFS BREAKS DOWN UPPER LEVEL TROUGH AND DEVELOPS WEST TO EAST ZONAL FLOW ACROSS THE NORTHERN TIER STATES WEDNESDAY NIGHT INTO THURSDAY...AND THE 09.12Z ECMWF KEEPS UPPER LEVEL TROUGH OVER THE EASTERN UNITED STATES. THE 09.12Z GFS/ECMWF/GEM SHOW DIFFERENCES IN PLACEMENT AND TIMING OF SURFACE FEATURES THROUGH THE PERIOD. THIS WILL HAVE IMPACTS ON TIMING OF SHOWERS/THUNDERSTORM CHANCES THROUGH THE PERIOD. THE 09.12Z GFS/GEM/ECMWF INDICATE DECENT LIFT/MOISTURE CONVERGENCE IN ASSOCIATION WITH EACH SHORTWAVE TROUGH EMBEDDED IN THE FLOW AND SURFACE FRONT/LOW THROUGH THE PERIOD. WILL CONTINUE ACTIVE WEATHER PATTERN THROUGH THE FORECAST PERIOD...WITH ON AND OFF SHOWER/THUNDERSTORM CHANCES. TEMPERATURES THROUGH THE PERIOD ARE EXPECTED TO BE NEAR OR SLIGHTLY BELOW NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 105 PM CDT THU JUL 9 2015 IT SEEMS CONDITIONS ARE MORE FAVORABLE FOR VALLEY FOG AT KLSE FRIDAY MORNING. WIND FORECASTS CONTINUE TO SUGGEST A DEEPER LIGHT WIND LAYER AND THE AIR MASS OVERHEAD WILL BE QUITE DRY. SINCE WE ARE EXPECTING CLEAR SKIES OVERNIGHT...HAVE INCLUDED SOME IFR BR CONDITIONS AT KLSE AROUND SUNRISE. THE CIG IFR CONDITIONS ARE OF HIGHER CONFIDENCE THAN THE VISIBILITY AT THIS TIME. THERE IS A CHANCE FOR BRIEF 1/4SM AT KLSE AROUND 11Z. IF YOU HAVE AVIATION INTERESTS AT KLSE IN THE MORNING...MONITOR FUTURE FORECASTS. OTHERWISE...VFR CONDITIONS ARE EXPECTED. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...DTJ LONG TERM...DTJ AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1003 AM CDT THU JUL 9 2015 .UPDATE... EXPECT DECREASING CLOUDS TODAY AS HIGH PRESSURE BUILDS IN BEHIND A DEPARTING LOW. 925 MB TEMPS RISING TO 18-19C TODAY SHOULD ALLOW FOR HIGHS CLOSER TO NORMAL VALUES THAN THE LAST COUPLE DAYS...THOUGH STILL LIKELY FALLING A COUPLE DEGREES SHORT OF AVERAGE. && .AVIATION/18Z TAFS/... COULD SEE SOME PATCHY FOG IN LOWER LYING AREAS LATER TONIGHT INTO EARLY FRIDAY MORNING AS HIGH PRESSURE BUILDS INTO THE AREA. OTHERWISE...VFR CONDITIONS ARE EXPECTED THROUGH FRIDAY. && .PREV DISCUSSION... /ISSUED 335 AM CDT THU JUL 9 2015/ SHORT TERM... TODAY...FORECAST CONFIDENCE HIGH DRY WEATHER TODAY AS HIGH PRESSURE BUILDS IN BEHIND SURFACE LOW AS IT TRACKS FROM CENTRAL IL TO THE IN/OH/MI BORDER AREA AROUND 12Z...AND PA/NY BY 00Z FRI. 500 MB TROUGH EXTENDING SOUTH FROM CLOSED LOW OVER HUDSON BAY THAT SWEEPS ACROSS U.P. OF MICHIGAN AND NORTHERN WISCONSIN OVERNIGHT...MOVING EAST OF THE STATE BY 18Z. STEEP LOW-LEVEL LAPSE RATES AND SOME MOISTURE NOTED ON FORECAST SOUNDINGS THIS AFTERNOON IN THE 4K-5K FT RANGE...BUT THIS LAYER NEVER FULLY SATURATES ON THE SOUNDINGS AND CU RULE ALSO SUPPORTS NO MORE THAN SCATTERED TO BRIEFLY BROKEN CUMULUS. WEAK COLD AIR ADVECTION EARLY THIS MORNING ON NORTH-NORTHEAST WINDS...THEN TEMPS STEADY OUT AS WINDS TURN NW TO WEST THIS AFTERNOON. 925 MB TEMPS SUPPORT MID-UPPER 70S...WITH SOME ADJUSTMENTS MADE FOR LINGERING CLOUDS IN THE SOUTH AND ONSHORE WINDS IN THE FAR EAST. TONIGHT...FORECAST CONFIDENCE HIGH 500 MB RIDGING DEVELOPS OVER THE PLAINS IN RESPONSE TO CLOSED LOW CURRENTLY MOVING ONSHORE OVER CENTRAL CALIFORNIA. THE RIDING BEGINS TO BUILD INTO THE WESTERN GREAT LAKES OVERNIGHT...WITH THE RIDGE AXIS CENTERED OVER MN/IA BY 12Z FRIDAY. SURFACE HIGH EXPANDS OVER THE REGION WITH LIGHT WINDS AND MOSTLY CLEAR SKIES BRINGING PATCHY FOG OVERNIGHT...WITH AREAS OF FOG IN THE WISCONSIN RIVER VALLEY. FRIDAY AND FRIDAY NIGHT... FORECAST CONFIDENCE HIGH. SURFACE HIGH PRESSURE WILL SHIFT EAST OF THE AREA ON FRI. SOUTHERLY WINDS WILL USHER WARMER AIR INTO SOUTHERN WI AND SOME LOCATIONS SHOULD SEE LOWER 80S BY LATE FRI AFTERNOON AS LONG AS THE CLOUDS WITH AN APPROACHING SHORTWAVE HOLD OFF. QUIET WEATHER WILL CONTINUE FOR FRIDAY NIGHT. THE DRY AIR ENTRENCHED OVER THE UPPER GREAT LAKES WILL KEEP PRECIP CHANCES MINIMAL. LONG TERM... SATURDAY THROUGH SUNDAY... FORECAST CONFIDENCE MEDIUM. A SHORTWAVE TRACKING NORTHEAST FROM THE PLAINS THROUGH IOWA WILL COMBINE WITH THE NOSE OF A LOW LEVEL JET AND 850MB FRONTOGENESIS TO BRING SHOWER AND THUNDERSTORM CHANCES TO SOUTHERN WI SATURDAY AFTERNOON AND NIGHT. THE SHORTWAVE WILL ALLOW FOR MID LEVEL COOLING AND STEEPENING LAPSE RATES AND INCREASING CAPE OVER THE AREA. THE LLJ SHOULD REMAIN FOCUSED ON SOUTHERN WI THROUGH SATURDAY EVENING BEFORE VEERING AWAY. THE 00Z ECMWF AND GFS BOTH SHOW AN MCS-LIKE FEATURE DEVELOPING IN THE IA/WI/IL AREA. SPC HAS THE SOUTHWEST PORTION OF THE MKX FORECAST AREA IN A MARGINAL RISK FOR SEVERE WEATHER. MODELS HAVE HAD QUITE THE TIME HANDLING THE LOCATION OF THE 850MB BAROCLINIC ZONE AND SUBSEQUENT LOCATION OF THE CONVECTION OVER THE PAST FEW DAYS. DESPITE CONTINUED DIFFERENCES... IT SEEMS THEY ARE HEADING TOWARD AGREEMENT... AT LEAST FOR THE SATURDAY-SAT NT TIME FRAME. SUNDAY SHOULD BE DRYING OUT IN THE MORNING. THEN ANOTHER WEAK SHORTWAVE IN NORTHWESTERLY FLOW OVER THE HIGH PRESSURE RIDGE STATIONED OVER THE HIGH PLAINS WILL TRACK THROUGH THE SOUTHERN WI AREA SUNDAY LATE AFTERNOON OR NIGHT AND POSSIBLY BRING ANOTHER ROUND OF CONVECTION. MONDAY THROUGH THURSDAY... FORECAST CONFIDENCE LOW. THE 00Z ECWMF IS MAINTAINING A MORE SOUTHERLY SOLUTION REGARDING THE LOCATION OF THE 850MB BAROCLINIC ZONE FOR THE FIRST PART OF NEXT WEEK. THE 00Z GFS IS BACK TO ITS NORTHERLY SOLUTION. THUS... LOW CONFIDENCE IN TEMPERATURES FOR THIS TIME PERIOD. BOTH SOLUTIONS STILL LEAD TO CHANCES FOR SHOWERS AND THUNDERSTORMS OVER SOUTHERN WI... BUT THE STRENGTH OF THE STORMS WILL BE DETERMINED BY WHICH SIDE OF THE FRONT THEY ARE ON. THE HIGH OVER THE HIGH PLAINS SHOWS NO SIGN OF BREAKING DOWN THROUGH ALL OF NEXT WEEK... SO EXPECT THIS NORTHWESTERLY... ACTIVE AND UNCERTAIN FLOW PATTERN TO CONTINUE OVER SOUTHERN WI. AVIATION/12Z TAFS/... EXPECT MVFR/IFR CIGS AND VSBYS IN THE FAR SE TO LIFT BETWEEN 12Z AND 15Z PER RAP FORECAST SOUNDINGS AND 03Z SREF VSBY PROBABILITIES...BUT WILL CONTINUE TO MONITOR TRENDS UP TO ISSUANCE AND ADJUST AS NEEDED. LOOKING FOR VFR CONDITIONS FOR THE REMAINDER OF THE FORECAST. STEEP LOW-LEVEL LAPSE RATES AND SOME MOISTURE NOTED ON FORECAST SOUNDINGS THIS AFTERNOON IN THE 4K-5K FT RANGE...BUT THIS LAYER NEVER FULLY SATURATES ON THE SOUNDINGS AND CU RULE ALSO SUPPORTS NO MORE THAN SCATTERED TO BRIEFLY BROKEN VFR LEVEL CUMULUS. SURFACE HIGH EXPANDS OVER THE REGION WITH LIGHT WINDS AND MOSTLY CLEAR SKIES BRINGING PATCHY FOG OVERNIGHT...WITH AREAS OF FOG IN THE WISCONSIN RIVER VALLEY. NAM GUIDANCE ALONE IN SHOWING ANY VSBY REDUCTIONS WITH FOG AT TAF SITES...SO WILL LEAVE OUT FOR NOW. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...DDV TODAY/TONIGHT AND AVIATION/MARINE...REM FRIDAY THROUGH WEDNESDAY...MRC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
335 AM CDT THU JUL 9 2015 .SHORT TERM... TODAY...FORECAST CONFIDENCE HIGH DRY WEATHER TODAY AS HIGH PRESSURE BUILDS IN BEHIND SURFACE LOW AS IT TRACKS FROM CENTRAL IL TO THE IN/OH/MI BORDER AREA AROUND 12Z...AND PA/NY BY 00Z FRI. 500 MB TROUGH EXTENDING SOUTH FROM CLOSED LOW OVER HUDSON BAY THAT SWEEPS ACROSS U.P. OF MICHIGAN AND NORTHERN WISCONSIN OVERNIGHT...MOVING EAST OF THE STATE BY 18Z. STEEP LOW-LEVEL LAPSE RATES AND SOME MOISTURE NOTED ON FORECAST SOUNDINGS THIS AFTERNOON IN THE 4K-5K FT RANGE...BUT THIS LAYER NEVER FULLY SATURATES ON THE SOUNDINGS AND CU RULE ALSO SUPPORTS NO MORE THAN SCATTERED TO BRIEFLY BROKEN CUMULUS. WEAK COLD AIR ADVECTION EARLY THIS MORNING ON NORTH-NORTHEAST WINDS...THEN TEMPS STEADY OUT AS WINDS TURN NW TO WEST THIS AFTERNOON. 925 MB TEMPS SUPPORT MID-UPPER 70S...WITH SOME ADJUSTMENTS MADE FOR LINGERING CLOUDS IN THE SOUTH AND ONSHORE WINDS IN THE FAR EAST. TONIGHT...FORECAST CONFIDENCE HIGH 500 MB RIDGING DEVELOPS OVER THE PLAINS IN RESPONSE TO CLOSED LOW CURRENTLY MOVING ONSHORE OVER CENTRAL CALIFORNIA. THE RIDING BEGINS TO BUILD INTO THE WESTERN GREAT LAKES OVERNIGHT...WITH THE RIDGE AXIS CENTERED OVER MN/IA BY 12Z FRIDAY. SURFACE HIGH EXPANDS OVER THE REGION WITH LIGHT WINDS AND MOSTLY CLEAR SKIES BRINGING PATCHY FOG OVERNIGHT...WITH AREAS OF FOG IN THE WISCONSIN RIVER VALLEY. FRIDAY AND FRIDAY NIGHT... FORECAST CONFIDENCE HIGH. SURFACE HIGH PRESSURE WILL SHIFT EAST OF THE AREA ON FRI. SOUTHERLY WINDS WILL USHER WARMER AIR INTO SOUTHERN WI AND SOME LOCATIONS SHOULD SEE LOWER 80S BY LATE FRI AFTERNOON AS LONG AS THE CLOUDS WITH AN APPROACHING SHORTWAVE HOLD OFF. QUIET WEATHER WILL CONTINUE FOR FRIDAY NIGHT. THE DRY AIR ENTRENCHED OVER THE UPPER GREAT LAKES WILL KEEP PRECIP CHANCES MINIMAL. .LONG TERM... SATURDAY THROUGH SUNDAY... FORECAST CONFIDENCE MEDIUM. A SHORTWAVE TRACKING NORTHEAST FROM THE PLAINS THROUGH IOWA WILL COMBINE WITH THE NOSE OF A LOW LEVEL JET AND 850MB FRONTOGENESIS TO BRING SHOWER AND THUNDERSTORM CHANCES TO SOUTHERN WI SATURDAY AFTERNOON AND NIGHT. THE SHORTWAVE WILL ALLOW FOR MID LEVEL COOLING AND STEEPENING LAPSE RATES AND INCREASING CAPE OVER THE AREA. THE LLJ SHOULD REMAIN FOCUSED ON SOUTHERN WI THROUGH SATURDAY EVENING BEFORE VEERING AWAY. THE 00Z ECMWF AND GFS BOTH SHOW AN MCS-LIKE FEATURE DEVELOPING IN THE IA/WI/IL AREA. SPC HAS THE SOUTHWEST PORTION OF THE MKX FORECAST AREA IN A MARGINAL RISK FOR SEVERE WEATHER. MODELS HAVE HAD QUITE THE TIME HANDLING THE LOCATION OF THE 850MB BAROCLINIC ZONE AND SUBSEQUENT LOCATION OF THE CONVECTION OVER THE PAST FEW DAYS. DESPITE CONTINUED DIFFERENCES... IT SEEMS THEY ARE HEADING TOWARD AGREEMENT... AT LEAST FOR THE SATURDAY-SAT NT TIME FRAME. SUNDAY SHOULD BE DRYING OUT IN THE MORNING. THEN ANOTHER WEAK SHORTWAVE IN NORTHWESTERLY FLOW OVER THE HIGH PRESSURE RIDGE STATIONED OVER THE HIGH PLAINS WILL TRACK THROUGH THE SOUTHERN WI AREA SUNDAY LATE AFTERNOON OR NIGHT AND POSSIBLY BRING ANOTHER ROUND OF CONVECTION. MONDAY THROUGH THURSDAY... FORECAST CONFIDENCE LOW. THE 00Z ECWMF IS MAINTAINING A MORE SOUTHERLY SOLUTION REGARDING THE LOCATION OF THE 850MB BAROCLINIC ZONE FOR THE FIRST PART OF NEXT WEEK. THE 00Z GFS IS BACK TO ITS NORTHERLY SOLUTION. THUS... LOW CONFIDENCE IN TEMPERATURES FOR THIS TIME PERIOD. BOTH SOLUTIONS STILL LEAD TO CHANCES FOR SHOWERS AND THUNDERSTORMS OVER SOUTHERN WI... BUT THE STRENGTH OF THE STORMS WILL BE DETERMINED BY WHICH SIDE OF THE FRONT THEY ARE ON. THE HIGH OVER THE HIGH PLAINS SHOWS NO SIGN OF BREAKING DOWN THROUGH ALL OF NEXT WEEK... SO EXPECT THIS NORTHWESTERLY... ACTIVE AND UNCERTAIN FLOW PATTERN TO CONTINUE OVER SOUTHERN WI. && .AVIATION/12Z TAFS/... EXPECT MVFR/IFR CIGS AND VSBYS IN THE FAR SE TO LIFT BETWEEN 12Z AND 15Z PER RAP FORECAST SOUNDINGS AND 03Z SREF VSBY PROBABILITIES...BUT WILL CONTINUE TO MONITOR TRENDS UP TO ISSUANCE AND ADJUST AS NEEDED. LOOKING FOR VFR CONDITIONS FOR THE REMAINDER OF THE FORECAST. STEEP LOW-LEVEL LAPSE RATES AND SOME MOISTURE NOTED ON FORECAST SOUNDINGS THIS AFTERNOON IN THE 4K-5K FT RANGE...BUT THIS LAYER NEVER FULLY SATURATES ON THE SOUNDINGS AND CU RULE ALSO SUPPORTS NO MORE THAN SCATTERED TO BRIEFLY BROKEN VFR LEVEL CUMULUS. SURFACE HIGH EXPANDS OVER THE REGION WITH LIGHT WINDS AND MOSTLY CLEAR SKIES BRINGING PATCHY FOG OVERNIGHT...WITH AREAS OF FOG IN THE WISCONSIN RIVER VALLEY. NAM GUIDANCE ALONE IN SHOWING ANY VSBY REDUCTIONS WITH FOG AT TAF SITES...SO WILL LEAVE OUT FOR NOW. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ TODAY/TONIGHT AND AVIATION/MARINE...REM FRIDAY THROUGH WEDNESDAY...MRC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1035 AM MDT THU JUL 9 2015 .UPDATE... ISSUED AT 1025 AM MDT THU JUL 9 2015 FORECAST PRETTY WELL ON TRACK. REMOVED MENTION OF THUNDERSTORMS THE REST OF THIS MORNING BUT STILL EXPECTING SHOWERS AND ISOLATED THUNDERSTORMS TO DEVELOP TOWARDS NOON TIME WITH INCREASING COVERAGE INTO THE AFTERNOON HOURS. LATEST MODELS HAVE BACKED OFF ON THE HIGHER CAPE VALUES THIS AFTERNOON. MODELS ARE NOW GENERALLY SHOWING BETWEEN 500 AND 1200 J/KG AND WITH LESS THAN IMPRESSIVE SHEAR VALUES THE THREAT FOR SEVERE THUNDERSTORMS IS VERY LOW. UPDATE ISSUED AT 753 AM MDT THU JUL 9 2015 THE DENSE FOG ALONG THE SOUTHERN LARAMIE RANGE BETWEEN CHEYENNE AND THE SUMMIT HAS LIFTED OVER THE LAST HOUR. THERE MAY BE A FEW POCKETS OF FOG LINGERING OVER THE AREA BUT THAT WILL QUICKLY ERODE. THE DENSE FOG ADVISORY IS CANCELLED. && .SHORT TERM...(TODAY THROUGH FRIDAY NIGHT) ISSUED AT 339 AM MDT THU JUL 9 2015 IN THE VERY NEAR TERM MAIN CONCERN IS WITH DENSE FOG THAT WILL CONTINUE FOR PORTIONS OF CENTRAL/WESTERN LARAMIE COUNTY AND SOUTHEASTERN ALBANY COUNTIES. VISIBILITIES ALONG I-80 AND I-25 IN THESE AREAS WILL GO UP AND DOWN BETWEEN 1/8TH OF A MILE TO 1 MILE THROUGH MID MORNING AS PERSISTENT SOUTH TO SOUTHEASTERLY UPSLOPE WINDS CONTINUE. WINDS SHOULD BRIEFLY GO A BIT MORE SOUTHWESTERLY BY LATE MORNING WHICH SHOULD HELP BREAK/LIFT THE AREAS OF FOG. DENSE FOG ADVISORY HAS BEEN ISSUED FOR THESE AREAS THROUGH 16Z. OTHERWISE...ACTIVE WEST TO SOUTHWESTERLY UPPER FLOW CONTINUES TODAY WITH PRECIPITABLE WATER VALUES DOWN A BIT...AROUND 0.80 INCHES MOST LOCATIONS...BUT STILL ENOUGH TO KEEP POPS ELEVATED FOR SCATTERED TO NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS WEST OF THE LARAMIE RANGE WITH SCATTERED SHOWERS AND POSSIBLE A FEW ISOLATED THUNDERSTORMS EAST OF THE LARAMIE RANGE BY AFTERNOON. MOST OF THE THUNDERSTORM ACTIVITY WILL ONCE AGAIN OCCUR OVER SE WYOMING TODAY WHERE MORE MIDLEVEL INSTABILITY IS AGAIN EXPECTED...BUT IN CONTRAST TO YESTERDAY WE DO EXPECT TO SEE A FEW MORE STORMS ALONG AND JUST EAST OF THE LARAMIE RANGE TODAY GIVEN AN INCREASE IN MIDLEVEL INSTABILITY AND MUCAPES AROUND 1100 J/KG AROUND CHEYENNE BY MID AFTERNOON. THE MODEL SOUNDINGS THIS MORNING DO SUGGEST A FEW STRONG TO MARGINALLY SEVERE STORMS ARE POSSIBLE TODAY ALONG THE I-25 CORRIDOR AND MAYBE JUST EAST...WITH LARGE HAIL BEING THE PRIMARY CONCERN. VIRTUALLY NO THUNDERSTORM ACTIVITY OCCURRED YESTERDAY EAST OF THE LARAMIES DUE TO A STRONGER CAPPING INVERSION AROUND 700 MB. TODAY WE STILL SEE A CAP AROUND 700 MB OVER THE NEBRASKA PANHANDLE...BUT THAT CAP IS WEAKER. TODAY THE MODELS ARE HINTING AT A BIT MORE INSTABILITY WITH MORE BREAKS IN THE LOW CLOUDS AND A SMALL POTENTIAL TO BREAK THE CAP SO INCLUDED A MENTION OF ISOLATED THUNDERSTORMS INTO THE NEBRASKA PANHANDLE. THUNDERSTORMS ARE NOT GOING TO BE FAST MOVERS TODAY GIVEN ONLY 10-15 KT OF STORM MOTION...SO AGAIN WE WILL NEED TO BE AWARE OF POTENTIAL ISOLATED LOCATIONS THAT COULD RECEIVE A HALF INCH OR MORE OF RAIN AND LOCALIZED FLOOD ISSUES WHERE STRONGER STORMS FORM UP...PARTICULARLY ALONG AND WEST OF THE LARAMIE RANGE WHERE STORMS SHOULD BE A BIT MORE NUMEROUS. ANY LINGERING STORMS INTO THE EVENING ARE EXPECTED TO WEAKEN FAST AFTER SUNSET WITH LOW POPS GOING INTO THE LATE EVENING HOURS. FOR FRIDAY...ONE THING THAT CATCHES THE EYE IS MODELS PEGGING THE WESTERN NEBRASKA PANHANDLE WITH A SIGNIFICANT INCREASE IN MIDLVEL INSTABILITY WITH FAIRLY FAT CAPES AROUND 2000-3000 J/KG FOR LOCATIONS SUCH AS ALLIANCE AND SIDNEY. SHEAR PROFILES ARE NOT OVERLY IMPRESSIVE FOR THE WESTERN NEBRASKA PANHANDLE FOR TOMORROW...BUT SOME WEAK ROTATIONS ARE POSSIBLE WITH STRONGER STORMS. GIVEN HIGHER INSTABILITY...WILL HIGHLIGHT POTENTIAL FOR SOME STRONGER STORMS TOMORROW WITH INCREASED HAIL POTENTIAL FOR OUR EASTERN-MOST ZONES. LATER FORECASTS CAN BETTER DEFINE ANY SEVERE THREAT FOR TOMORROW. THREAT FOR STRONGER STORMS TOMORROW SHOULD REMAIN ACROSS THE NEBRASKA PANHANDLE WITH LOWER THREAT EAST TO THE LARAMIE RANGE OF WYOMING. .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 339 AM MDT THU JUL 9 2015 NICE...DRY WEATHER FOR THE WEEKEND INTO THE FIRST PART OF NEXT WEEK AS THE LOW THAT IS CURRENTLY OVER NORTHERN CALIFORNIA GETS DRAWN NORTH INTO MONTANA AND THE SOUTHERN CANADIAN PROVINCES. RIDGE BUILDS INTO WYOMING WITH 700MB TEMPERATURES CLIMBING TO +12 TO +14C. COULD BE WINDY OUT WEST AS GFS 700MB WINDS INCREASE TO NEAR 40KTS FOR BOTH SATURDAY AND ESPECIALLY SUNDAY. NEXT CHANCES FOR SHOWERS AND THUNDERSTORMS APPEARS TUESDAY AS MONSOONAL MOISTURE GETS DRAWN NORTH OUT OF COLORADO AND THE DESERT SOUTHWEST. SHOWERS AND THUNDERSTORMS INITIALLY OVER THE SNOWY AND SIERRA MADRE RANGES TUESDAY AFTERNOON...BECOMING MORE WIDESPREAD TUESDAY NIGHT INTO WEDNESDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 510 AM MDT THU JUL 9 2015 IFR/LIFR CONDITIONS EXPECTED TO PERSIST THROUGH THE MORNING HOURS AND POSSIBLY INTO THE EARLY AFTERNOON FOR KCYS. SOUTHERN PANHANDLE SHOULD KEEP IFR CONDITIONS OUT THERE WITH LATEST HRRR FINALLY BREAKING OUT KSNY BY 16-17Z. SHOULD SEE FAIRLY WIDESPREAD CONVECTION THIS AFTERNOON ONCE AGAIN AFTER STRATUS BREAKS UP. && .FIRE WEATHER... ISSUED AT 339 AM MDT THU JUL 9 2015 ABOVE NORMAL RELATIVE HUMIDITY AND CHANCES FOR THUNDERSTORMS WILL BE NOTED TODAY ACROSS SOUTH CENTRAL AND SOUTHEASTERN WYOMING WITH ISOLATED THUNDERSTORMS POSSIBLE ACROSS THE WESTERN NEBRASKA PANHANDLE THIS AFTERNOON. THE WEATHER PATTERN IS PROJECTED TO BECOME DRIER AND WARMER FOR THE WEEKEND. THE MONSOONAL PATTERN OF INCREASED MOISTURE AND RAIN CHANCES COMES BACK BY THE MIDDLE OF NEXT WEEK. DUE TO INCREASED HUMIDITY FIRE WEATHER CONCERNS THROUGH FRIDAY ARE MINIMAL. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...SML SHORT TERM...JG LONG TERM...GCC AVIATION...GCC FIRE WEATHER...JG
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
801 AM MDT THU JUL 9 2015 .UPDATE... ISSUED AT 753 AM MDT THU JUL 9 2015 THE DENSE FOG ALONG THE SOUTHERN LARAMIE RANGE BETWEEN CHEYENNE AND THE SUMMIT HAS LIFTED OVER THE LAST HOUR. THERE MAY BE A FEW POCKETS OF FOG LINGERING OVER THE AREA BUT THAT WILL QUICKLY ERODE. THE DENSE FOG ADVISORY IS CANCELLED. && .SHORT TERM...(TODAY THROUGH FRIDAY NIGHT) ISSUED AT 339 AM MDT THU JUL 9 2015 IN THE VERY NEAR TERM MAIN CONCERN IS WITH DENSE FOG THAT WILL CONTINUE FOR PORTIONS OF CENTRAL/WESTERN LARAMIE COUNTY AND SOUTHEASTERN ALBANY COUNTIES. VISIBILITIES ALONG I-80 AND I-25 IN THESE AREAS WILL GO UP AND DOWN BETWEEN 1/8TH OF A MILE TO 1 MILE THROUGH MID MORNING AS PERSISTENT SOUTH TO SOUTHEASTERLY UPSLOPE WINDS CONTINUE. WINDS SHOULD BRIEFLY GO A BIT MORE SOUTHWESTERLY BY LATE MORNING WHICH SHOULD HELP BREAK/LIFT THE AREAS OF FOG. DENSE FOG ADVISORY HAS BEEN ISSUED FOR THESE AREAS THROUGH 16Z. OTHERWISE...ACTIVE WEST TO SOUTHWESTERLY UPPER FLOW CONTINUES TODAY WITH PRECIPITABLE WATER VALUES DOWN A BIT...AROUND 0.80 INCHES MOST LOCATIONS...BUT STILL ENOUGH TO KEEP POPS ELEVATED FOR SCATTERED TO NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS WEST OF THE LARAMIE RANGE WITH SCATTERED SHOWERS AND POSSIBLE A FEW ISOLATED THUNDERSTORMS EAST OF THE LARAMIE RANGE BY AFTERNOON. MOST OF THE THUNDERSTORM ACTIVITY WILL ONCE AGAIN OCCUR OVER SE WYOMING TODAY WHERE MORE MIDLEVEL INSTABILITY IS AGAIN EXPECTED...BUT IN CONTRAST TO YESTERDAY WE DO EXPECT TO SEE A FEW MORE STORMS ALONG AND JUST EAST OF THE LARAMIE RANGE TODAY GIVEN AN INCREASE IN MIDLEVEL INSTABILITY AND MUCAPES AROUND 1100 J/KG AROUND CHEYENNE BY MID AFTERNOON. THE MODEL SOUNDINGS THIS MORNING DO SUGGEST A FEW STRONG TO MARGINALLY SEVERE STORMS ARE POSSIBLE TODAY ALONG THE I-25 CORRIDOR AND MAYBE JUST EAST...WITH LARGE HAIL BEING THE PRIMARY CONCERN. VIRTUALLY NO THUNDERSTORM ACTIVITY OCCURRED YESTERDAY EAST OF THE LARAMIES DUE TO A STRONGER CAPPING INVERSION AROUND 700 MB. TODAY WE STILL SEE A CAP AROUND 700 MB OVER THE NEBRASKA PANHANDLE...BUT THAT CAP IS WEAKER. TODAY THE MODELS ARE HINTING AT A BIT MORE INSTABILITY WITH MORE BREAKS IN THE LOW CLOUDS AND A SMALL POTENTIAL TO BREAK THE CAP SO INCLUDED A MENTION OF ISOLATED THUNDERSTORMS INTO THE NEBRASKA PANHANDLE. THUNDERSTORMS ARE NOT GOING TO BE FAST MOVERS TODAY GIVEN ONLY 10-15 KT OF STORM MOTION...SO AGAIN WE WILL NEED TO BE AWARE OF POTENTIAL ISOLATED LOCATIONS THAT COULD RECEIVE A HALF INCH OR MORE OF RAIN AND LOCALIZED FLOOD ISSUES WHERE STRONGER STORMS FORM UP...PARTICULARLY ALONG AND WEST OF THE LARAMIE RANGE WHERE STORMS SHOULD BE A BIT MORE NUMEROUS. ANY LINGERING STORMS INTO THE EVENING ARE EXPECTED TO WEAKEN FAST AFTER SUNSET WITH LOW POPS GOING INTO THE LATE EVENING HOURS. FOR FRIDAY...ONE THING THAT CATCHES THE EYE IS MODELS PEGGING THE WESTERN NEBRASKA PANHANDLE WITH A SIGNIFICANT INCREASE IN MIDLVEL INSTABILITY WITH FAIRLY FAT CAPES AROUND 2000-3000 J/KG FOR LOCATIONS SUCH AS ALLIANCE AND SIDNEY. SHEAR PROFILES ARE NOT OVERLY IMPRESSIVE FOR THE WESTERN NEBRASKA PANHANDLE FOR TOMORROW...BUT SOME WEAK ROTATIONS ARE POSSIBLE WITH STRONGER STORMS. GIVEN HIGHER INSTABILITY...WILL HIGHLIGHT POTENTIAL FOR SOME STRONGER STORMS TOMORROW WITH INCREASED HAIL POTENTIAL FOR OUR EASTERN-MOST ZONES. LATER FORECASTS CAN BETTER DEFINE ANY SEVERE THREAT FOR TOMORROW. THREAT FOR STRONGER STORMS TOMORROW SHOULD REMAIN ACROSS THE NEBRASKA PANHANDLE WITH LOWER THREAT EAST TO THE LARAMIE RANGE OF WYOMING. .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 339 AM MDT THU JUL 9 2015 NICE...DRY WEATHER FOR THE WEEKEND INTO THE FIRST PART OF NEXT WEEK AS THE LOW THAT IS CURRENTLY OVER NORTHERN CALIFORNIA GETS DRAWN NORTH INTO MONTANA AND THE SOUTHERN CANADIAN PROVINCES. RIDGE BUILDS INTO WYOMING WITH 700MB TEMPERATURES CLIMBING TO +12 TO +14C. COULD BE WINDY OUT WEST AS GFS 700MB WINDS INCREASE TO NEAR 40KTS FOR BOTH SATURDAY AND ESPECIALLY SUNDAY. NEXT CHANCES FOR SHOWERS AND THUNDERSTORMS APPEARS TUESDAY AS MONSOONAL MOISTURE GETS DRAWN NORTH OUT OF COLORADO AND THE DESERT SOUTHWEST. SHOWERS AND THUNDERSTORMS INITIALLY OVER THE SNOWY AND SIERRA MADRE RANGES TUESDAY AFTERNOON...BECOMING MORE WIDESPREAD TUESDAY NIGHT INTO WEDNESDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 510 AM MDT THU JUL 9 2015 IFR/LIFR CONDITIONS EXPECTED TO PERSIST THROUGH THE MORNING HOURS AND POSSIBLY INTO THE EARLY AFTERNOON FOR KCYS. SOUTHERN PANHANDLE SHOULD KEEP IFR CONDITIONS OUT THERE WITH LATEST HRRR FINALLY BREAKING OUT KSNY BY 16-17Z. SHOULD SEE FAIRLY WIDESPREAD CONVECTION THIS AFTERNOON ONCE AGAIN AFTER STRATUS BREAKS UP. && .FIRE WEATHER... ISSUED AT 339 AM MDT THU JUL 9 2015 ABOVE NORMAL RELATIVE HUMIDITY AND CHANCES FOR THUNDERSTORMS WILL BE NOTED TODAY ACROSS SOUTH CENTRAL AND SOUTHEASTERN WYOMING WITH ISOLATED THUNDERSTORMS POSSIBLE ACROSS THE WESTERN NEBRASKA PANHANDLE THIS AFTERNOON. THE WEATHER PATTERN IS PROJECTED TO BECOME DRIER AND WARMER FOR THE WEEKEND. THE MONSOONAL PATTERN OF INCREASED MOISTURE AND RAIN CHANCES COMES BACK BY THE MIDDLE OF NEXT WEEK. DUE TO INCREASED HUMIDITY FIRE WEATHER CONCERNS THROUGH FRIDAY ARE MINIMAL. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...SML SHORT TERM...JG LONG TERM...GCC AVIATION...GCC FIRE WEATHER...JG
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
513 AM MDT THU JUL 9 2015 .SHORT TERM...(TODAY THROUGH FRIDAY NIGHT) ISSUED AT 339 AM MDT THU JUL 9 2015 IN THE VERY NEAR TERM MAIN CONCERN IS WITH DENSE FOG THAT WILL CONTINUE FOR PORTIONS OF CENTRAL/WESTERN LARAMIE COUNTY AND SOUTHEASTERN ALBANY COUNTIES. VISIBILITIES ALONG I-80 AND I-25 IN THESE AREAS WILL GO UP AND DOWN BETWEEN 1/8TH OF A MILE TO 1 MILE THROUGH MID MORNING AS PERSISTENT SOUTH TO SOUTHEASTERLY UPSLOPE WINDS CONTINUE. WINDS SHOULD BRIEFLY GO A BIT MORE SOUTHWESTERLY BY LATE MORNING WHICH SHOULD HELP BREAK/LIFT THE AREAS OF FOG. DENSE FOG ADVISORY HAS BEEN ISSUED FOR THESE AREAS THROUGH 16Z. OTHERWISE...ACTIVE WEST TO SOUTHWESTERLY UPPER FLOW CONTINUES TODAY WITH PRECIPITABLE WATER VALUES DOWN A BIT...AROUND 0.80 INCHES MOST LOCATIONS...BUT STILL ENOUGH TO KEEP POPS ELEVATED FOR SCATTERED TO NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS WEST OF THE LARAMIE RANGE WITH SCATTERED SHOWERS AND POSSIBLE A FEW ISOLATED THUNDERSTORMS EAST OF THE LARAMIE RANGE BY AFTERNOON. MOST OF THE THUNDERSTORM ACTIVITY WILL ONCE AGAIN OCCUR OVER SE WYOMING TODAY WHERE MORE MIDLEVEL INSTABILITY IS AGAIN EXPECTED...BUT IN CONTRAST TO YESTERDAY WE DO EXPECT TO SEE A FEW MORE STORMS ALONG AND JUST EAST OF THE LARAMIE RANGE TODAY GIVEN AN INCREASE IN MIDLEVEL INSTABILITY AND MUCAPES AROUND 1100 J/KG AROUND CHEYENNE BY MID AFTERNOON. THE MODEL SOUNDINGS THIS MORNING DO SUGGEST A FEW STRONG TO MARGINALLY SEVERE STORMS ARE POSSIBLE TODAY ALONG THE I-25 CORRIDOR AND MAYBE JUST EAST...WITH LARGE HAIL BEING THE PRIMARY CONCERN. VIRTUALLY NO THUNDERSTORM ACTIVITY OCCURRED YESTERDAY EAST OF THE LARAMIES DUE TO A STRONGER CAPPING INVERSION AROUND 700 MB. TODAY WE STILL SEE A CAP AROUND 700 MB OVER THE NEBRASKA PANHANDLE...BUT THAT CAP IS WEAKER. TODAY THE MODELS ARE HINTING AT A BIT MORE INSTABILITY WITH MORE BREAKS IN THE LOW CLOUDS AND A SMALL POTENTIAL TO BREAK THE CAP SO INCLUDED A MENTION OF ISOLATED THUNDERSTORMS INTO THE NEBRASKA PANHANDLE. THUNDERSTORMS ARE NOT GOING TO BE FAST MOVERS TODAY GIVEN ONLY 10-15 KT OF STORM MOTION...SO AGAIN WE WILL NEED TO BE AWARE OF POTENTIAL ISOLATED LOCATIONS THAT COULD RECEIVE A HALF INCH OR MORE OF RAIN AND LOCALIZED FLOOD ISSUES WHERE STRONGER STORMS FORM UP...PARTICULARLY ALONG AND WEST OF THE LARAMIE RANGE WHERE STORMS SHOULD BE A BIT MORE NUMEROUS. ANY LINGERING STORMS INTO THE EVENING ARE EXPECTED TO WEAKEN FAST AFTER SUNSET WITH LOW POPS GOING INTO THE LATE EVENING HOURS. FOR FRIDAY...ONE THING THAT CATCHES THE EYE IS MODELS PEGGING THE WESTERN NEBRASKA PANHANDLE WITH A SIGNIFICANT INCREASE IN MIDLVEL INSTABILITY WITH FAIRLY FAT CAPES AROUND 2000-3000 J/KG FOR LOCATIONS SUCH AS ALLIANCE AND SIDNEY. SHEAR PROFILES ARE NOT OVERLY IMPRESSIVE FOR THE WESTERN NEBRASKA PANHANDLE FOR TOMORROW...BUT SOME WEAK ROTATIONS ARE POSSIBLE WITH STRONGER STORMS. GIVEN HIGHER INSTABILITY...WILL HIGHLIGHT POTENTIAL FOR SOME STRONGER STORMS TOMORROW WITH INCREASED HAIL POTENTIAL FOR OUR EASTERN-MOST ZONES. LATER FORECASTS CAN BETTER DEFINE ANY SEVERE THREAT FOR TOMORROW. THREAT FOR STRONGER STORMS TOMORROW SHOULD REMAIN ACROSS THE NEBRASKA PANHANDLE WITH LOWER THREAT EAST TO THE LARAMIE RANGE OF WYOMING. .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 339 AM MDT THU JUL 9 2015 NICE...DRY WEATHER FOR THE WEEKEND INTO THE FIRST PART OF NEXT WEEK AS THE LOW THAT IS CURRENTLY OVER NORTHERN CALIFORNIA GETS DRAWN NORTH INTO MONTANA AND THE SOUTHERN CANADIAN PROVINCES. RIDGE BUILDS INTO WYOMING WITH 700MB TEMPERATURES CLIMBING TO +12 TO +14C. COULD BE WINDY OUT WEST AS GFS 700MB WINDS INCREASE TO NEAR 40KTS FOR BOTH SATURDAY AND ESPECIALLY SUNDAY. NEXT CHANCES FOR SHOWERS AND THUNDERSTORMS APPEARS TUESDAY AS MONSOONAL MOISTURE GETS DRAWN NORTH OUT OF COLORADO AND THE DESERT SOUTHWEST. SHOWERS AND THUNDERSTORMS INITIALLY OVER THE SNOWY AND SIERRA MADRE RANGES TUESDAY AFTERNOON...BECOMING MORE WIDESPREAD TUESDAY NIGHT INTO WEDNESDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 510 AM MDT THU JUL 9 2015 IFR/LIFR CONDITIONS EXPECTED TO PERSIST THROUGH THE MORNING HOURS AND POSSIBLY INTO THE EARLY AFTERNOON FOR KCYS. SOUTHERN PANHANDLE SHOULD KEEP IFR CONDITIONS OUT THERE WITH LATEST HRRR FINALLY BREAKING OUT KSNY BY 16-17Z. SHOULD SEE FAIRLY WIDESPREAD CONVECTION THIS AFTERNOON ONCE AGAIN AFTER STRATUS BREAKS UP. && .FIRE WEATHER... ISSUED AT 339 AM MDT THU JUL 9 2015 ABOVE NORMAL RELATIVE HUMIDITY AND CHANCES FOR THUNDERSTORMS WILL BE NOTED TODAY ACROSS SOUTH CENTRAL AND SOUTHEASTERN WYOMING WITH ISOLATED THUNDERSTORMS POSSIBLE ACROSS THE WESTERN NEBRASKA PANHANDLE THIS AFTERNOON. THE WEATHER PATTERN IS PROJECTED TO BECOME DRIER AND WARMER FOR THE WEEKEND. THE MONSOONAL PATTERN OF INCREASED MOISTURE AND RAIN CHANCES COMES BACK BY THE MIDDLE OF NEXT WEEK. DUE TO INCREASED HUMIDITY FIRE WEATHER CONCERNS THROUGH FRIDAY ARE MINIMAL. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...DENSE FOG ADVISORY UNTIL 10 AM MDT THIS MORNING FOR WYZ116>118. NE...NONE. && $$ SHORT TERM...JG LONG TERM...GCC AVIATION...GCC FIRE WEATHER...JG
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1011 PM MDT WED JUL 8 2015 .UPDATE... ISSUED AT 921 PM MDT WED JUL 8 2015 SHOWER ACTIVITY HAS GENERALLY COME TO AN END ACROSS MUCH OF THE AREA THIS EVENING. HOWEVER...A FEW SHOWERS STILL LINGER IN AREAS TO THE WEST OF THE LARAMIE RANGE AS WELL AS PARTS OF THE SOUTHERN NEBRASKA PANHANDLE. THE HRRR SUGGESTS SHOWERS WILL CONTINUE TO DECREASE IN COVERAGE OVER THE NEXT FEW HOURS AS WEAK SHORTWAVE RIDGING AND MODEST MID-LEVEL DRYING TAKES PLACE...SO WE TRENDED LOWER WITH POPS THROUGH THE NIGHT. OVERALL FORECAST IS IN GOOD SHAPE...BUT FOG IS BECOMING MORE LIKELY WITH THE MOIST LLVL AIR MASS IN PLACE AFTER RECENT RAINS. NAM/GFS BUFKIT SOUNDINGS SHOW GOOD LLVL SATURATION AFTER 06Z WITH WEAK UPSLOPE STAYING INTACT ALONG THE LARAMIE RANGE. THEREFORE...HAVE ADDED PATCHY FOG FOR MOST OF THE PLAINS FROM 06-15Z. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 254 PM MDT WED JUL 8 2015 AREA OF SHOWERS CONTINUES TO SLIP SLOWLY EASTWARD OVER MUCH OF THE PANHANDLE AND FAR SE WY THIS AFTERNOON WITH RADAR SHOWING A CIRCULATION CENTER OVER NRN COLORADO TO THE SE OF CHEYENNE. IT APPEARS THIS CIRCULATION IS DRAWING SOME DRIER AIR SOUTH OVER SE WY WITH SHOWER ACTIVITY DIMINISHING OVER THAT AREA. EXPECT THE BULK OF THE PCPN TO CONTINUE OVER THE SE HALF OF THE CWA THIS EVENING WHILE DIMINISHING GRADUALLY ACROSS THE ENTIRE CWA. MILD CONDITIONS TO CONTINUE THURSDAY WITH SCTD TO NUMEROUS SHOWERS AND SOME TSTRMS REFIRING LATE IN THE MORNING THROUGH THE AFTERNOON AS MODEST INSTABILITIES GENERALLY AROUND 500 J/KG DEVELOP OVER MUCH OF THE CWA AND WEAK IMPULSES RIDE UP OVER THE REGION AHEAD OF AN UPPER LOW THAT WILL DRIFT ONSHORE OVER CALIFORNIA. ACTIVITY SHOULD ONCE AGAIN DECREASE DURING THE EVENING WITH WEAK RIDGING PASSING ACROSS THE AREA. SW FLOW ALOFT OVER THE CWA FRIDAY WILL BRING IN WARMING TEMPS WITH SOME GUSTY WINDS OVER THE WESTERN PARTS IN A FAVORABLE PATTERN. SE WINDS OVER THE PANHANDLE WILL BRING IN MORE MOISTURE AND INCREASE INSTABILITIES TO AROUND 1500 J/KG SO A FEW STRONGER STORMS POSSIBLE THERE...AIDED BY A SFC TROF THAT SHOULD LIE OVER THE HIGH PLAINS. .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 254 PM MDT WED JUL 8 2015 HEIGHTS WILL RISE THIS WEEKEND AS THE UPPER HIGH BECOMES RE- ESTABLISHED OVR THE SRN PLAINS. SUBSIDENCE AND WARMER MID-LEVEL TEMPS WILL SUPPRESS MOST CONVECTION...YIELDING A GENERALLY DRY WEEKEND. THERE IS AN OUTSIDE CHANCE FOR A FEW HIGH-BASED SHOWERS AND THUNDERSTORMS OVR THE HIER TERRAIN ON SATURDAY AFTERNOON AS THE 12Z ECMWF BRUSHES THE CWFA WITH SHORTWAVE ENERGY MOVING ACROSS NRN WYOMING. THE GFS SUGGESTS NO SUCH SHORTWAVE. LEFT ANY MENTION OUT OF THE FORECAST FOR NOW GIVEN INCONSISTENCIES AND WARMING TEMPS. H7 TEMPERATURES WILL WARM TO 15-16C...WHICH WILL BOOST HIGH TEMPERATURES BACK TO NR NORMAL WITH 80S AND SOME LOW 90S EXPECTED. UPPER HIGH WILL RETROGRADE WEST INTO THE SRN ROCKIES EARLY NEXT WEEK...WHICH WILL AMPLIFY RIDGING ACROSS THE CENTRAL AND NORTHERN ROCKIES. MOISTURE WILL RETURN TO THE MED BOWS AS EARLY AS MONDAY AFTERNOON. HOWEVER...THE BETTER/MORE SEASONAL CONVECTIVE CHANCES WILL HOLD OFF UNTIL TUE-WED ELSEWHERE...AS UPPER HEIGHTS WILL FALL IN FLATTENING ZONAL FLOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1009 PM MDT WED JUL 8 2015 WYOMING TAFS...MOUNTAINS OBSCURED WITH IFR DEVELOPING AT LARAMIE AND CHEYENNE OVERNIGHT IN FOG AND LOW CLOUDS WITH VFR AT RAWLINS. VFR PREVAILS BY LATE THURSDAY MORNING WITH LOCALIZED MVFR IN SHOWERS AND THUNDERSTORMS IN THE AFTERNOON. NEBRASKA TAFS...IFR DEVELOPING OVERNIGHT. BECOMING VFR AT ALL SITES BY LATE THURSDAY MORNING...WITH LOCALIZED MVFR AT SITES IN THE AFTERNOON WITH THUNDERSTORMS IN THE VICINITY. && .FIRE WEATHER... ISSUED AT 254 PM MDT WED JUL 8 2015 NO CONCERNS EXPECTED THROUGH THE WEEKEND WITH FAIRLY WIDESPREAD SHOWERS AND A FEW STORMS AGAIN THURSDAY. DRYING SOME ALONG WITH WARMER CONDITIONS FRIDAY THROUGH THE WEEKEND BUT CONDITIONS REMAINING NON-CRITICAL. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...CLH SHORT TERM...RE LONG TERM...CAH AVIATION...RUBIN FIRE WEATHER...RE
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
200 AM MST SAT JUL 11 2015 .SYNOPSIS...LITTLE CHANGE IN THE WEATHER PATTERN IS FORECAST THE NEXT SEVERAL DAYS. DRY WEATHER WITH NEAR NORMAL TEMPERATURES ARE EXPECTED IN SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA...WITH A THREAT OF AFTERNOON AND EVENING MOUNTAIN THUNDERSTORMS IN EASTERN ARIZONA...GENERALLY EAST OF PHOENIX. && .DISCUSSION... UNSEASONABLY STRONG UPPER LOW OVER NRN CA/WRN NV CONTINUED TO WEAKEN AND LIFT NEWD EARLY THIS MORNING...MEANWHILE THE SWLY FLOW AHEAD OF IT REMAINED STRONG ENOUGH OVER THE DESERT SOUTHWEST TO CONFINE MOISTURE AND CONVECTION TO FAR ERN AND SERN AZ...MAINLY AREAS EAST OF PHOENIX. IR IMAGERY AT 2 AM SHOWED CLEAR SKIES WEST OF PHOENIX WITH PARTLY CLOUDY SKIES PRESENT FROM PHOENIX EAST. A COUPLE OF INTERESTING THINGS TO NOTE...DESPITE THE CONTINUED PRESENCE OF RELATIVELY DRY SOUTHWEST FLOW ALOFT OVER THE AREA AS SEEN IN THE LATEST 00Z PLOT DATA...MOISTURE DID INCREASE IN THE PHOENIX AREA DURING THE DAY YESTERDAY AND THE PHOENIX RAOB SHOWED PWAT UP TO 1.35 INCHES...WHICH WAS HIGHER THAN TUCSON WHICH REPORTED 1.21 INCHES. ALSO...FRI EVENING SURFACE DEWPOINTS OVER THE CENTRAL DESERTS HAD CLIMBED INTO THE LOW TO MID 50S...A RISE OF MORE THAN 20 DEGREES OVER THE PAST 24 HOURS. SO...DESPITE THE SOUTHWEST FLOW ALOFT WITH A VERY LAMINAR UPPER STREAMLINE FIELD AND NO SIGNIFICANT DISTURBANCES MOVING THROUGH THE FLOW...AROUND MIDNIGHT ISOLATED SHOWERS/STORMS STARTED TO DEVELOP OVER THE NORTH VALLEY...NEAR NEW RIVER...AND THEY MOVED QUICKLY TO THE NORTH/NORTHEAST. LATEST HRRR SUGGESTS THESE STORMS WILL WEAKEN AND MOVE OUT OF THE AREA WITHIN THE NEXT 1-2 HOURS LEAVING PARTLY CLOUDY OR MOSTLY CLEAR SKIES BEHIND FOR THE REST OF TONIGHT. FOR THE WEEKEND GUIDANCE REMAINS CONSISTENT THAT THE GRADUALLY WEAKENING TROFFING TO OUR NORTHWEST WILL ALLOW THE MAIN UPPER HIGH TO BUILD BACK WESTWARD...ALLOWING HEIGHTS TO RISE AND TEMPS TO CLIMB BACK TOWARDS NORMAL READINGS. STILL...THE MAIN HIGH CENTER REMAINS SUPPRESSED WELL TO THE EAST/SOUTHEAST OF ARIZONA AND AS SUCH STEERING FLOW REMAINS SOUTH/SOUTHWESTERLY. AS SUCH WE ARE STILL EXPECTED CONVECTION TO BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX...MAINLY AREAS OF SOUTHERN GILA COUNTY AS WELL AS EASTERN PORTIONS OF ZONE 28 ACROSS NORTHWEST PINAL COUNTY. ALL AREAS WEST OF MARICOPA COUNTY SHOULD STAY GENLY CLEAR WITH POPS LOW SINGLE DIGITS OR ZERO. AS FOR THE UPCOMING WORK WEEK...MONDAY THROUGH FRIDAY...GUIDANCE INCLUDING THE GFS AND ECMWF CONTINUE TO SUGGEST THAT TROFFING TO OUR NORTHWEST...OVER THE NORTHWESTERN STATES...WILL REMAIN STRONG ENOUGH TO KEEP THE MAIN UPPER HIGH SUPPRESSED TO OUR EAST AND SOUTHEAST. THIS WILL RESULT IN A CONTINUED SOUTHWESTERLY FLOW ACROSS MOST OF OUR AREA THROUGH THE PERIOD. MOISTURE/INSTABILITY/CAPE WILL BE MINIMAL FROM PHOENIX WESTWARD EACH DAY AND CONVECTION WILL REMAIN CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST AND SOUTHEAST OF PHOENIX. WE ARE LOOKING AT A VERY LOW GRADE MONSOON FOR THE DURATION OF THE FORECAST PERIOD. HIGH TEMPERATURES WILL CLIMB SLIGHTLY ABOVE NORMAL EACH DAY WITH HOTTER DESERTS REACHING NEAR 110 DEGREES. DESPITE H5 HEIGHTS STAYING MOSTLY AT OR BELOW 591DM EACH DAY...THE DRIER AIR AND SUNNY AFTERNOONS WILL ALLOW TEMPS TO RISE A BIT ABOVE SEASONAL NORMALS EACH DAY. && .PREVIOUS DISCUSSION... THROUGH NEXT FRIDAY...ITS UNUSUAL THAT A LARGE AMOUNT OF MOMENTUM AND ENERGY IN THE WEST COAST TROF HAS BEEN ABLE TO CONTROL THE FLOW PATTERN OVER AZ IN MID JULY. THIS HAS PREVENTED THE SUBTROPICAL HIGH PRESSURE SYSTEM FROM SEASONALLY BULGING TO AZ THE PAST SEVERAL DAYS...INCLUDING NEXT WEEK. THEREFORE A PERSISTENCE FORECAST IS IN ORDER FOR OUR AREA...SOUTHEAST CA TO SOUTH CENTRAL AZ...WHERE MONSOON MOISTURE WILL BE DRAWN NORTH INTO SOUTHEAST AZ PROVIDING A DAILY THREAT OF AFTERNOON/EVENING THUNDERSTORMS OVER THE MOUNTAINS OF SOUTHERN GILA COUNTY ZONE 24. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... WINDS SHOULD GRADUALLY TAPER OFF THIS EVENING AND OVERNIGHT AS THE BOUNDARY LAYER STABILIZES WITH THE LOSS OF DAYTIME HEATING...EVENTUALLY BECOMING LIGHT/DIURNAL IN NATURE AROUND 12Z. NOT ANTICIPATING ANY STORMS AT ANY OF THE TERMINALS...NOR ANY IMPACTS FROM DISTANT STORMS. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... SUNDAY THROUGH FRIDAY... THE UPPER LEVEL FLOW PATTERN WILL SHIFT SLIGHTLY AS THE SUB-TROPICAL HIGH SHIFTS WESTWARD AND REESTABLISHES ITSELF OVER THE DESERT SOUTHWEST STARTING SUNDAY. THIS WILL LEAD TO WARMING TEMPERATURES AND LIKELY AT LEAST SOME MOISTURE RETURN INTO EASTERN AND POSSIBLY CENTRAL ARIZONA. THUNDERSTORM CHANCES WILL MOSTLY BE LIMITED TO HIGHER TERRAIN LOCATIONS NORTH AND EAST OF PHOENIX WITH ONLY SLIM CHANCES OF ANY ACTIVITY OVER THE DESERTS. AFTERNOON HUMIDITY LEVELS IN A 15-20 PERCENT RANGE THROUGH MONDAY WILL LOWER SOMEWHAT GOING INTO THE MIDDLE OF NEXT WEEK AS TEMPERATURES RISE TO SLIGHTLY ABOVE NORMAL LEVELS. WINDS WILL BE BREEZY AND MOSTLY OUT OF THE SOUTHWEST EACH AFTERNOON WITH GUSTS UP TO 20 MPH. && .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...CB AVIATION...LEINS FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
400 AM MDT SAT JUL 11 2015 .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 400 AM MDT SAT JUL 11 2015 FORECAST PWATS REMAIN SOMEWHAT HIGH TODAY WITH VALUES OF AN INCH OR JUST ABOVE FAVORED IN THE RAP AND NAM WHILE GFS AND SREF PUT VALUES BETWEEN .75 TO .9 INCHES. THE LOCATION OF THE HIGH PRESSURE OVER TX AND AND TROUGH OFF THE WEST COAST STILL LOOKS FAVORABLE FOR MOISTURE TO CONTINUE TO ADVECT IN FROM THE SOUTH. NAM12 AND GFS IN PRETTY GOOD AGREEMENT THAT CONVECTION WILL FIRE IN THE FOUR CORNERS AROUND NOON AND OVERSPREAD THE AREA TO THE NORTHEAST. THE JET STREAM IS LOCATED FROM SRN CALIF...UP THROUGH LAS VEGAS AND CENTRAL UTAH WHICH WILL INCREASE ASCENT AND ALSO DIVERGENCE ALOFT WHICH IS ALWAYS HELPFUL IN CONVECTION. STRONGER STORMS AND SHOWERS THAT FORM WILL BRING HEAVY RAIN...SMALL HAIL AND SOME GUSTY WINDS...SIMILAR TO WHAT WE`VE SEEN ALL WEEK. SOME CONVECTION WILL CONTINUE THROUGH MIDNIGHT WITH VERY ISOLD CONVECTION AFTER THAT. THE TRICKY PART OF THE FORECAST IS SUNDAY. THE NAM PAINTS AN ALMOST COMPLETELY DRY DAY FOR THE CWA WHILE THE GFS FAVORS THE SAN JUANS AND AREAS SOUTH FOR MORE PRECIP. NOT SOLD ON NAM AS AVAILABLE MOISTURE...THOUGH LOWER...WILL STILL REMAIN AND THOUGH THE MOST ENERGETIC PART OF THE JET STREAM SHIFTS TO THE PLAIN STATES...ENOUGH SUPPORT MAY ALLOW SOME RAIN TO FALL. WITH THAT IN MIND...KEPT SCHC CONVECTION IN FORECAST FOR QUITE A BIT OF THE FORECAST AREA. MIGHT BE A BIT MUCH BUT WE CAN TRIM THE FORECAST AS NEWER MODELS COME IN. TEMPS START TO RISE BUT WILL REMAIN BELOW CLIMO. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 400 AM MDT SAT JUL 11 2015 MODELS ASSERT THAT THE LARGE SCALE PATTERN WILL REMAIN LARGELY UNCHANGED DURING THE EARLY PART OF THE COMING WEEK. CONSEQUENTLY ...EXPECT THE MONSOONAL SURGE WILL CONTINUE AS SUBTROPICAL MOISTURE IS DRAWN NORTHEASTWARD ACROSS THE AREA BETWEEN HIGH PRESSURE OVER THE SOUTHERN PLAINS AND A TROUGH OF LOW PRESSURE OVER THE WEST COAST. THE MOISTURE LADEN AIR WILL FUEL MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS FAVORING THE MOUNTAINS. NOCTURNAL STORMS ARE POSSIBLE DURING THIS PERIOD AS MORE SUBTLE FEATURES NOT WELL HANDLED BY LARGE SCALE MODELS MAY COME INTO PLAY. MODELS POINT TO A SHIFT IN THE PATTERN AT MIDWEEK AS ENERGY EJECTED FROM THE WEST COAST TROUGH MOVES EASTWARD OVER THE NORTHERN ROCKIES FLATTENING THE RIDGE. AS THIS OCCURS HIGH PRESSURE OVER THE SOUTHERN PLAINS WILL EXPAND WESTWARD CUTTING OFF THE INFLUX OF MOISTURE. DRIER AIR IN WESTERLY FLOW WILL ERODE THE MOISTURE OVER THE AREA DURING THE LATTER PART OF THE WEEK BRINGING A DECREASE IN AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS AS EARLY AS WEDNESDAY. MODELS DIFFER IN TIMING WITH GFS FASTER WITH THIS EVOLUTION...BUT BY THE END OF THE WEEK MODELS WERE IN AGREEMENT WITH GREATLY REDUCED MOIST CONVECTION. TEMPERATURES WILL REMAIN SUPPRESSED BY CLOUDS AND SHOWER ACTIVITY DURING THE EARLY PART OF THE WEEK SO EXPECT BELOW NORMAL VALUES TO CONTINUE. DRIER AIR TRANSLATES INTO GREATER SOLAR INSOLATION DURING THE LATTER HALF OF THE COMING WEEK AND AFTERNOON HIGHS WILL TREND UPWARD AS RESULT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 400 AM MDT SAT JUL 11 2015 VFR CONDITIONS WILL PREVAIL ACROSS THE AREA BEFORE MIDDAY...THOUGH A WEAK DISTURBANCE UPSTREAM MAY GET A FEW SHOWERS AND THUNDERSTORMS STARTED OVER THE SAN JUAN/S PRIOR TO NOON. DAYTIME HEATING COMBINED WITH MONSOON MOISTURE WILL FUEL SCATTERED THUNDERSTORMS DURING THE AFTERNOON AND INTO THE EARLY EVENING. THIS ACTIVITY WILL RESULT IN AREAS OF MOUNTAIN OBSCURATION ALONG WITH OUTFLOW WINDS TO 40 MPH. CHANCES OF STORMS LOWERING CIGS BELOW ILS BREAKPOINTS ARE LOW WITH OUTFLOW WINDS IMPACTING AIRPORT OPERATIONS MORE LIKELY. SHOWERS AND THUNDERSTORMS WILL LARGELY DIMINISH AFTER SUNSET. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...NONE. UT...NONE. && $$ SHORT TERM...TGR LONG TERM...NL AVIATION...NL
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1116 PM MDT FRI JUL 10 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 247 PM MDT FRI JUL 10 2015 DRIER AIR HAS MOVED OVR MUCH OF THE AREA TODAY...AND SO FAR ONLY A FEW STORMS HAVE DEVELOPED OVR THE SRN SANGRES AND THE SWRN CO MTNS. THE HRRR SHOWS ONLY SOME ISOLD PCPN ACRS THE FORECAST AREA THIS EVENING...THEN ENDING WITH THE LOSS OF HEATING. THE NAM IS QUITE SIMILAR. LATE TONIGHT THE NAM AND GFS SHOW A LEE TROF OVR THE FAR SERN PLAINS...AND EARLY SAT MORNING THE NAM SHOWS THE POTENTIAL FOR SOME LIGHT PCPN OVR OR NR KIOWA COUNTY...WHILE THE GFS IS DRY. WL GO WITH A DRY SOLUTION FOR NOW. ON SAT AN UPR HIGH CENTER WL MOVE WESTWARD INTO ERN TX...WITH AN UPR TROF BEING ALONG THE WEST COAST. THERE WL BE LIMITED MSTR OVR THE FORECAST AREA ON SAT AND AS A RESULT...JUST SOME ISOLD SHOWERS AND TSTMS ARE EXPECTED OVR AND NR THE MTN AREAS. HIGH TEMPS ON SAT SHOULD BE AROUND AVERAGE. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 247 PM MDT FRI JUL 10 2015 NO BIG CHANGES TO CURRENT FORECAST WITH WARMER AND DRIER WEATHER EXPECTED ACROSS THE AREA THROUGH THE WEEKEND...ESPECIALLY ACROSS THE SOUTHEAST PLAINS. ISOLATED HIGH BASED CONVECTION CAN NOT BE RULED OUT OVER AND NEAR THE HIGHER TERRAIN LATE SATURDAY AFTERNOON WITH ANY STORMS QUICKLY DIMINISHING WITH THE LOSS OF SOLAR INSOLATION. A SLIGHT INCREASE IN AVAILABLE MOISTURE WITHIN THE WEST TO SOUTHWEST FLOW ALOFT ON SUNDAY WILL ALLOW FOR SLIGHTLY BETTER COVERAGE OF AFTERNOON AND EVENING STORMS OVER AND NEAR THE HIGHER TERRAIN SUNDAY AFTERNOON AND EVENING...WITH STORMS REMAINING MAINLY HIGH BASED PRODUCING MORE LIGHTNING AND GUSTY WINDS THAN RAINFALL. WARM TEMPS ALOFT (14C TO 18C AT H7)...LESS EXPECTED CONVECTION AND WEAK DOWNSLOPE FLOW...WILL KEEP TEMPERATURES AT AND ABOVE SEASONAL AVERAGES IN THE 80S TO MID 90S ACROSS THE LOWER ELEVATIONS AND MAINLY 60S AND 70S ACROSS THE HIGHER TERRAIN. IT STILL LOOKS LIKE THE PATTERN WILL GRADUALLY BECOME COOLER AND WETTER THROUGH THE MIDDLE OF NEXT WEEK...AS THE UPPER HIGH OVER THE SOUTHERN ROCKIES DRIFTS SOUTH AND EAST ALLOWING FOR INCREASING SUBTROPICAL MOISTURE INTO THE REGION. THIS...ALONG WITH A FEW DISTURBANCES MOVING ACROSS THE NORTHERN ROCKIES AND HIGH PLAINS SENDING WEAK FRONTS ACROSS THE EASTERN PLAINS...WILL ALLOW FOR BETTER CHANCES OF WETTING RAINS AREAWIDE THROUGH THE MIDDLE OF NEXT WEEK. WARMER AND DRIER WEATHER MAY AGAIN BE IN THE OFFING FOR LATE NEXT WEEK...AS DRIER AIR WITHIN DEVELOPING WESTERLY FLOW ALOFT LOOKS TO WORK ITS WAY INTO THE REGION. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1115 PM MDT FRI JUL 10 2015 VFR CONDITIONS ARE EXPECTED NEXT 24H AT ALL 3 TAF SITES...KPUB...KALS AND KCOS. WINDS WILL BE LIGHT AND DIURNALLY DRIVEN. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...28 LONG TERM...MW AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
342 AM EDT SAT JUL 11 2015 .DISCUSSION... TODAY-TONIGHT...RIDGE ALOFT WILL SHIFT WESTWARD BUT STILL REMAIN EXTENDED OVER THE SOUTHERN CONUS. THIS PATTERN HAS PRODUCED A SWATH OF SUBSIDENCE/DRYING ALOFT ACROSS THE ATLANTIC AND ADJACENT PORTIONS OF EAST CENTRAL FLORIDA. AT THE SURFACE...THE RIDGE AXIS WILL DROP SOUTH OF THE CAPE WITH THE SLIGHT INCREASE IN SOUTH- SOUTHWEST FLOW DELAYING THE SEA BREEZE ESPECIALLY ALONG THE VOLUSIA COAST AN HOUR OR TWO BEHIND FRIDAY. AIRMASS WILL INITIALLY BE VERY DRY WITH GPS PRECIPITABLE WATER VALUES ABOUT 1.2 TO 1.3 INCHES...MAYBE A LITTLE GREATER INLAND NORTH SECTIONS. THIS WILL ENSURE THAT RAIN CHANCES REMAIN BELOW NORMAL. EVEN THOUGH THE HRRR IS GENERATING ISOLATED ACTIVITY ALONG THE INLAND MOVING SEA BREEZE BOUNDARY...THINK THAT THE DRYNESS OF THE AIR WILL PRECLUDE MENTIONABLE CHANCES EXCEPT WHERE THE EAST/WEST BOUNDARY COLLISION OCCURS NEAR THE LAKE/ORANGE COUNTY LINE LATE IN THE DAY. LIMITED AND DELAYED AFTERNOON CONVECTION WILL ALLOW TEMPS TO REACH THE LOWER 90S ALONG THE COAST. MID 90S WERE INDICATED INLAND YESTERDAY AT THE MAIN OBSERVATION AND FAWN SITES. THEREFORE HAVE STUCK WITH HIGHS IN THE MID 90S ACROSS THE INTERIOR AGAIN TODAY... WITH NORTH COASTAL ZONE EVEN PUSHING TOWARDS 93-95 DEGREES. SUN-TUE...EASTERN EXTENT OF RIDGE OVER THE SOUTHERN CONUS SHIFTS WESTWARD AS TROUGH DEVELOPS DOWN OVER THE EASTERN U.S. INTO EARLY NEXT WEEK. THIS SHIFTS SFC RIDGE AXIS SOUTH OF THE REGION. LOSS OF SUPPRESSION FROM RIDGE ALOFT AND DEEPER MOISTURE MOVING INTO THE AREA WILL LEAD TO INCREASING RAIN CHANCES THROUGH THE PERIOD. RAIN CHANCES REMAIN OUT OF THE FORECAST ALONG THE COAST FROM THE CAPE SOUTHWARD SUNDAY WHERE DRIER AIR LINGERS. HIGHEST POPS (UP TO 40-50 PERCENT) WILL EXIST FROM I-4 CORRIDOR WEST WHERE BOUNDARY COLLISIONS WILL BE FAVORED LATER IN THE DAY AND EVENING. BEST RAIN CHANCES THEN SHIFT ACROSS EAST CENTRAL FL INTO EARLY NEXT WEEK AS LOW LEVEL FLOW BECOMES W/SW...FAVORING BOUNDARY COLLISIONS AND GREATER STORM COVERAGE OVER THE REGION. HIGHS WILL GENERALLY RANGE FROM THE LOW 90S ALONG THE COAST TO MID 90S INTERIOR ON SUNDAY...WITH LOW 90S OVER MUCH OF THE AREA MON/TUE AS CONVECTIVE COVERAGE IS FORECAST TO BE GREATER. WED-FRI...TROUGH OVER THE EASTERN U.S. WEAKENS INTO LATE WEEK WITH SUBTROPICAL RIDGE AXIS SLOWLY LIFTING BACK NORTH...BUT STILL REMAINING NEAR TO JUST SOUTH OF LAKE OKEECHOBEE. LOW LEVEL W/SW FLOW MID WEEK GRADUALLY WEAKENS AND BECOMES MORE S/SW BY WEEKS END WHICH SHOULD ALLOW THE SEA BREEZE TO HAVE MORE INLAND MOVEMENT... ESPECIALLY SOUTH OF THE CAPE FRI. LINGERING DEEP MOISTURE WILL KEEP SCATTERED SHOWERS AND STORMS IN THE FORECAST...PUSHING EASTWARD OVER EAST CENTRAL FL WED/THU WITH BEST RAIN CHANCES THEN TRANSITIONING TO THE INTERIOR FRI. TEMPS WILL REMAIN NEAR SEASONAL NORMS WITH HIGHS IN THE LOW 90S AND OVERNIGHT LOWS IN THE LOW TO MID 70S. && .AVIATION...ANOTHER DAY WITH PRIMARILY VFR CONDITIONS. A SLIGHT CHANCE FOR STORMS EXISTS LATE THIS AFTERNOON KSFB-KMCO-KISM WITH A SLIGHTLY GREATER CHANCE AT KLEE BY EVENING. CHANCES ARE TOO LOW TO INCLUDE IN THE TAFS JUST YET. && .MARINE... TODAY-TONIGHT...CONTINUED FAVORABLE CONDITIONS FOR SMALL CRAFT. SURFACE RIDGE AXIS WILL MIGRATE SOUTH ACROSS THE WATERS TODAY. THIS WILL PROVIDE FOR LIGHT WINDS EXCEPT FOR A 10 KNOT AFTERNOON SEA BREEZE. THEN AS THE RIDGE SLIDES FARTHER SOUTH TONIGHT...SOUTH/SOUTHWEST WINDS WILL INCREASE TO 10-15 KNOTS FROM ABOUT THE CAPE NORTHWARD. DRIER THAN NORMAL AIR WAS PRODUCING MOSTLY CLEAR SKIES EARLY THIS MORNING...SO DO NOT THINK THERE WILL BE SIGNIFICANT CONVECTION OVER THE COASTAL WATERS. SUN...RIDGE AXIS ACROSS THE AREA WILL ALLOW WINDS TO START OUT OF THE S/SW IN THE MORNING AROUND 5-10 KTS BECOMING S/SE AND INCREASING UP TO 10-15 KNOTS INTO THE AFT AS SEA BREEZE FORMS AND MOVES INLAND. SEAS WILL RANGE FROM 1-3 FEET NEARSHORE UP TO 3-4 FEET OFFSHORE. MON-WED...RIDGE AXIS SHIFTS SOUTH OF CENTRAL FL WITH WINDS MORE PREDOMINANTLY S/SW THROUGH THE PERIOD AND WIND SPEEDS GENERALLY LESS THAN 15 KNOTS. SEAS WILL CONTINUE TO REMAIN AOB 4FT. MAIN CONCERN FOR BOATERS WILL BE AN INCREASED THREAT FOR OFFSHORE MOVING STORMS IN THE AFT AND EVE...PRODUCING GUSTY WINDS. && .PRELIMINARY POINT TEMPS/POPS... DAB 93 74 95 74 / 10 10 30 30 MCO 95 75 96 75 / 10 10 40 40 MLB 91 74 93 75 / 10 10 10 10 VRB 91 71 92 73 / 10 10 10 10 LEE 95 78 96 77 / 30 20 50 40 SFB 95 76 96 76 / 10 10 30 40 ORL 95 77 96 76 / 10 10 40 40 FPR 91 71 92 72 / 10 10 10 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ SHORT TERM...LASCODY LONG TERM....WEITLICH
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
346 AM CDT SAT JUL 11 2015 .SHORT TERM: (THROUGH LATE THIS AFTERNOON) ISSUED AT 330 AM CDT SAT JUL 11 2015 CLUSTER OF ELEVATED THUNDERSTORMS EXTENDING FROM SOUTHEAST IA INTO NORTH CENTRAL MO ARE OCCURING IN ASSOCIATION WITH GOOD MOISTURE CONVERGENCE ASSOCIATED WITH THE SOUTHWESTERLY LLJ. BOTH THE DETERMINISTIC AND CAMS ARE IN RELATIVELY GOOD AGREEMENT SPREADING THIS ACTIVITY EASTWARD THIS MORNING IN CONJUCTION WITH THE STEERING FLOW ALOFT AND GRADUALLY VEERING LLJ. THERE IS SOME QUESTION ON THE SOUTHERN EXTENT OF ANY STORM POTENTIAL. GIVEN THE CURRENT MID CLOUD EXTENT AND VEERING LLJ, I THINK THE POTENTIAL FOR ISOLATED- WIDELY SCATTERED STORMS EXISTS THIS MORNING AT LEAST DOWN TO THE I-70 CORRIDOR WHICH IS JUST NORTH OF THE LIFTING WARM FRONT. IN THE WAKE OF THE CLOUDS, CONVECTION AND LIFTING WARM FRONT, WARMING LOW AND MID LEVELS SHOULD RESULT IN MUCH WARMER TEMPERATURES TODAY AND MORE SEASONABLE FOR THIS TIME IN JULY. GLASS .LONG TERM: (TONIGHT THROUGH FRIDAY) ISSUED AT 330 AM CDT SAT JUL 11 2015 THERE ARE LOTS OF QUESTIONS AND FORECAST CAVEATS TONIGHT INTO TUESDAY. THE GENERAL PATTERN OF AN EXPANSIVE UPPER HIGH ANCHORED ACROSS THE SOUTHERN PLAINS AND OUR LOCATION ON THE PERIPHERAL NORTHWEST FLOW ALOFT POINTS TO BOTH BIG HEAT AND HUMIDITY AND POTENTIAL THUNDERSTORM CHANCES. TO THIS END THE MODELS ARE QUITE VARIED ON THE STRENGTH OF LOW-MID LEVEL WARMING AND EASTERN EDGE OF THE STRONGER CAPPING AND PLACEMENT OF QPF. THE ECMWF SEEMS MOST AGRESSIVE WITH THE EXTENT OF QPF INTO OUR CWA DURING MOST OF THE FORECAST PERIODS. THE GENERAL THOUGHT IS THIS THAT THE VEERING SOUTHWESTERLY LLJ AND ONLY MODERATELY WARM MID LEVEL TEMPS TONIGHT ARE SUFFICIENT TO MERIT THUNDERSTORM CHANCES TONIGHT INTO EARLY SUNDAY MORNING ACROSS PRIMARILY NORTHERN MO INTO CENTRAL IL. BY SUNDAY AFTERNOON, STRONG WARMING IN THE LOW-MID LEVELS SHOULD RESULT IN A FORMIDABLE CAP TO SURFACE BASED CONVECTION. A RELATIVELY HOT AFTERNOON IS ON TAP WITH HIGHS IN THE 90S AND AFTERNOON HEAT INDICES OF 100-103. THESE HI VALUES ARE LARGELY BASED ON THE BELIEF THE MODELS ARE A BIT AGRESSIVE IN THE MAGNITUDE OF THE SURFACE DEW POINTS. IF THE TDS ARE HIGHER THEN WE MIGHT HAVE SOME 105 HIS. SUNDAY NIGHT INTO EARLY MONDAY A SHORT WAVE TROF DIGGING FROM THE UPPER MS INTO THE LOWER GREAT LAKES SHOULD LEAD TO HEIGHT FALLS ALOFT AND COOLING AND WESTWARD RETREAT OF THE EDGE OF CAPPING, ALLOWING FOR A THREAT OF THUNDERSTORMS PRIMARILY FOCUSED FROM FAR EASTERN MO INTO IL. THIS COULD BE A COMBINATION OF SOUTHEAST MOVING CONVECTIVE COMPLEXES/CLUSTERS AND NEW DEVELOPMENT. MONDAY LOOKS TO BE THE HOTTEST DAY OVER THE NEXT 3 WITH CONTINUED WARMING OF THE LOW-MID LEVELS - H85 TEMPS AOA +24 DEGC AND H7 TEMPS OF +12 TO +14 DEGC BY 00Z TUES. THIS LOOKS LIKE A DAY THAT A HEAT ADVISORY WILL PROBABLY BE NEEDED PROVIDED THE OVERNIGHT CONVECTION FROM SUNDAY SOMEHOW DOESN`T HAMPER IT. HEAT INDICES IN MANY LOCATIONS SHOULD BE 105+. I DON`T ANTICIPATE MUCH CONVECTION BEYOND THE MORNING RESIDUAL AND THE AFTERNOON CAP SHOULD BECOME STOUT. SUNDAY NIGHT HOWEVER IT APPEARS THAT A SIGNIFICANT SEVERE WEATHER EVENT COULD DEVELOP WITH ANOTHER SHORT WAVE TROF DIGGING FROM THE UPPER MS VALLEY INTO THE LOWER GREAT LAKES AND OH VALLEY PROVIDING FORCING AND WEAKENING THE CAP. STRONG INSTABILITY WILL BE IN PLACE AND DEEP LAYER SHEAR IS RATHER STOUT AT 35-40 KTS. ALL THE PARAMETERS ARE SUGGESTIVE OF A POTENTIAL DERECHO SWEEPING FROM EASTERN IA/NORTHWEST IL SOUTHEASTWARD AND IMPACTING FAR EASTERN MO INTO IL. A FRONTAL BOUNDARY FINALLY SINKS INTO THE AREA TUESDAY AND THEN WAVERS NORTH AND SOUTH DURING THE WEEK RESULTING IN PROLONGED THUNDERSTORM CHANCES IN THE VICINITY OF THE BOUNDARY AND SEASONABLY HOT TEMPERATURES TO THE SOUTH OF IT. GLASS && .AVIATION: (FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1039 PM CDT FRI JUL 10 2015 SHORT RANGE MODELS (RAP, HRRR) ARE AGREEING THE SHOWERS AND THUNDERSTORMS WILL DEVELOP ALONG THE WARM FRONT AS IT MOVES NORTH OVERNIGH. THE ATMOSPHERE LOOK BEST OR UIN WHERE THERE APPEARS TO BE BETTER DEEP MOISTURE CONVERGENCE. TIMEING ON CURRENT TAF LOOKS GOOD WITH SHROT RANGE MODELS SO WILL CHANGE PROB30 TO A TEMPO GROUP. A VCSH FOR COU MAY BE ALL THAT IS NEEDED FOR A COUPLE OF HOURS AS IT LOOKS LIKE THE DEVELOPMENT WILL BE NORTH AND EAST. WILL BRING THE FRONT THROUGH COU AT 14Z AND UIN AND 18Z. SPECIFICS FOR KSTL: RAP AND HRRR DEVELOP PRECIPITATON NW-SE ALONG THE ADVANCING WARM FRONT. IF IT HAPPENS IT LOOKS TO BE 10Z TO 14Z. STILL, CONFIDENCE IS NOT HIGH ENOUGH TO GO ABOVE VICINITY FOR NOW. WILL DELAY THE WIND SHIFT WITH THE WARM FRONT TO 18Z FOLLWING THE RAP/HRRR. JPK && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
1143 PM MDT FRI JUL 10 2015 .AVIATION... 06Z TAF CYCLE ROUNDS OF TS/SH WILL IMPACT THE SE PLAINS THROUGH THE REST OF THE OVERNIGHT. ROW STANDS A GOOD CHANCE TO BE IMPACTED. OTHERWISE VERY LIMITED CONVECTION ACROSS THE FORECAST AREA. PERHAPS A STRAY STRIKE OR TWO ACROSS THE WESTERN HIGHLANDS. ISOLD TO SCT STORMS WILL ONCE AGAIN FIRE UP ACROSS THE AREA ON SATURDAY. USING VCTS/VCSH AT MOST OF THE TERMINAL SITES EXCEPT FOR LVS. IT APPEARS THAT THE HIGHLANDS WEST OF LVS SHOULD HAVE ANOTHER DOWN DAY. BASED ON THE STEERING FLOW...INSTABILITY AND MOISTURE AVAILABILITY...ROW HAS THE BEST CHANCE OF BEING DIRECTLY IMPACTED BUT REALLY CANT RULE OUT MOST OF THE TERMINAL SITES. 50 && .PREV DISCUSSION...304 PM MDT FRI JUL 10 2015... .SYNOPSIS... SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE WEEKEND AS THE MONSOON MOISTURE PLUME STRETCHES FROM SOUTH TO NORTH OVER THE STATE. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE WITH ANY OF THE STRONGER STORMS...ALONG WITH GUSTY WINDS AND SMALL HAIL. UPPER LEVEL HIGH PRESSURE WILL DRIFT WEST THROUGH NEXT WEEK AND ALLOW FOR DRIER AND HOTTER CONDITIONS TO RETURN. ISOLATED TO SCATTERED SHOWERS AND STORMS WILL STILL DEVELOP AROUND THE HIGH TERRAIN... ESPECIALLY OVER WESTERN NEW MEXICO. && .DISCUSSION... AN UNSEASONABLY DEEP UPPER LEVEL LOW OVER THE GREAT BASIN IS FORCING A STRONG 40-60KT UPPER JET OVER AZ/NM. A 594DM H5 UPPER HIGH DRIFTING WEST OVER EAST TX IS TAPPING A JUICY ATMOSPHERE FROM MEXICO AND SHIFTING IT NORTHWARD INTO THE FASTER UPPER LEVEL FLOW. STRONG DIFFLUENCE AND TERRAIN CIRCULATIONS WITH AFTERNOON HEATING IN THIS PATTERN IS FORCING SEVERAL STRONG TO EVEN SEVERE STORMS ACROSS THE SW PORTION OF THE STATE. OTHERWISE STORM COVERAGE IS LESS TODAY AND ACTIVITY IS BUMPING ALONG QUICKLY FOR JULY...THUS LIMITING THE FLASH FLOOD THREAT. HRRR GUIDANCE SHOWS CONVECTIVE ACTIVITY MAKING IT INTO THE RIO GRANDE VALLEY AND EASTERN PLAINS BETWEEN 3PM AND 7PM. NOT MUCH CHANGE ANTICIPATED SATURDAY WITH THE OVERALL CIRCULATION PATTERN REMAINING QUASI-STATIONARY. STORM MOTIONS MAY BECOME A BIT MORE SOUTH TO NORTH AS THE UPPER HIGH DRIFTS WEST AND IMPINGES ON THE UPPER LEVEL SW FLOW. BY SUNDAY...ANOTHER BURST IS ADVERTISED BY MID-RANGE MODEL GUIDANCE. INCREASED POPS AGAIN SUNDAY WITH LOCALLY HEAVY RAINFALL THREAT INCREASING. FOR THE REMAINDER OF NEXT WEEK... A SLOW DRYING AND WARMING TREND IS ON TAP. HIGH TEMPS WILL TREND TO NEAR NORMAL WITH SLOW-MOVING STORMS FAVORING HIGH TERRAIN AREAS. GUYER && .FIRE WEATHER... DAILY ROUNDS OF WETTING RAIN IN THE FORM OF THUNDERSTORMS AND SHOWERS WILL CONTINUE THROUGH THE FORECAST PERIOD...THOUGH COVERAGE WILL LIKELY DECREASE AS DRIER AND WARMER CONDITIONS DEVELOP. BY EARLY NEXT WEEK...EASTERN ZONES WILL SEE THE FEWEST STORMS WHILE WESTERN AND CENTRAL ZONES REMAIN MORE ACTIVE. TEMPERATURES WILL FINALLY REACH NORMAL OR HIGHER LEVELS ACROSS THE EAST BY SUNDAY AND MUCH OF THE STATE BY THURSDAY. VENTILATION LOOKS TO BE GENERALLY GOOD TO EXCELLENT MOST DAYS WITH LOWER VALUES...AND SOME AREAS OF POOR TO FAIR VENTILATION ON SUNDAY AND THURSDAY. INTERESTING PATTERN FOR JULY WITH AN UNSEASONABLY DEEP CLOSED LOW POSITIONED CENTERED OVER THE GREAT BASIN AND THE ASSOCIATED UPPER JET EXTENDED FROM NORTHERN BAJA...ACROSS ARIZONA AND OVER NORTHWEST NEW MEXICO. SHOWERS AND THUNDERSTORMS THIS AFTERNOON ARE MOVING FAIRLY QUICKLY TO THE NORTHEAST...AND SOME ARE PRODUCING HAIL AND LOCALLY HEAVY RAIN. LOWER DEWPOINTS NOTED OVER ARIZONA THIS MORNING HAVE NOT REALLY TRANSLATED INTO WESTERN ZONES TODAY. THUS... OVERNIGHT RH RECOVERIES LOOK TO BE GOOD TO EXCELLENT ALL ZONES. MEANWHILE...UPPER LEVEL HIGH PRESSURE CONTINUES TO BUILD OVER THE SOUTHEAST STATES...MAINTAINING THE FLUX OF MONSOON MOISTURE FROM MEXICO INTO NEW MEXICO. MODELS CONTINUE TO DEPICT THE UPPER HIGH BUILDING OVER TEXAS...RESULTING IN A WESTWARD NUDGE OF THE MONSOON PLUME. SATURDAY LOOKS TO BE FAIRLY ACTIVE MOST ZONES...WITH THE EXTREME NORTHWEST AND NORTHEAST CORNERS LEAST FAVORED. BY SUNDAY THROUGH TUESDAY...EASTERN ZONES LOOK TO REMAIN FAIRLY DRY WITH THE HIGH TERRAIN OF WESTERN AND CENTRAL ZONES FAVORED. 05 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1212 AM CDT SAT JUL 11 2015 .UPDATE... ISSUED AT 1212 AM CDT SAT JUL 11 2015 NO MAJOR CHANGES MADE TO THE FORECAST. UPDATE ISSUED AT 933 PM CDT FRI JUL 10 2015 NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE AS ANY CONVECTION FOR THE REMAINDER OF THE NIGHT WILL BE ISOLATED AT BEST AS THE LOW LEVEL JET INCREASES UNDER SOUTHWEST FLOW ALOFT. THIS IS SUPPORTED BY THE 00 UTC NAM AND 00-01 UTC HRRR ITERATIONS. UPDATE ISSUED AT 733 PM CDT FRI JUL 10 2015 WHILE ISOLATED CELLS HAVE INITIATED ACROSS SOUTH CENTRAL NORTH DAKOTA THIS EVENING...WEAK LAPSE RATES AND SHEAR HAVE LEAD TO VERY QUICK DISSIPATION OF THESE SHOWERS/STORMS. THE HRRR THUS FAR THIS EVENING FROM RUN TO RUN HAS OVER DEVELOPED CONVECTION ACROSS THE DAKOTAS GIVEN THE HIGH CAPE/LOW CIN ENVIRONMENT. THUS...FAVORED THE 18 UTC NAM AND 15 UTC SREF WHOSE QPF FIELDS ARE CLOSET TO RADAR TRENDS THROUGH 00 UTC. DO EXPECT AN ISOLATED THUNDERSTORM THREAT TO CONTINUE THROUGH THE NIGHT AS THE LOW LEVEL JET INCREASES UNDER SOUTHWEST FLOW ALOFT. HOWEVER...CONTINUED WEAK SHEAR PRECLUDES A SEVERE THREAT. UPDATE ISSUED AT 457 PM CDT FRI JUL 10 2015 BASED ON RADAR TRENDS THROUGH 2150 UTC OF ISOLATED TO SCATTERED THUNDERSTORMS DEVELOPING ACROSS NORTH CENTRAL SOUTH DAKOTA AND A TIME LAGGED ENSEMBLE OF THE 18-20 UTC HRRR RUNS...INTRODUCED POPS TO THE FAR SOUTH CENTRAL AND JAMES RIVER VALLEY FOR LATE THIS AFTERNOON AND EARLY EVENING. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 224 PM CDT FRI JUL 10 2015 CURRENT SURFACE ANALYSIS PLACES LOW OVER CENTRAL MONTANA WITH TROUGH OVER SOUTHEAST MONTANA INTO NORTHEAST WYOMING. UPPER LEVEL ANALYSIS PLACES BROAD UPPER LOW NEAR THE NORTHERN GREAT BASIN WITH A VARIETY OF WEAK VORTICES WORKING AROUND THE SYSTEM. OVER OUR AREA...SHORT WAVE LIFTING THROUGH SOUTHWESTERLY FLOW IS STARTING TO PRODUCE SOME LIGHT CONVECTION OVER SOUTHEAST MONTANA INTO NORTHERN WYOMING. FOR THE REST OF THIS AFTERNOON INTO TONIGHT...AFOREMENTIONED SHORT WAVE WILL CONTINUE TO LIFT TOWARDS THE AREA...WITH SOME THUNDERSTORMS POSSIBLY DEVELOPING TOWARDS LATE AFTERNOON OVER THE SOUTHWEST. WAVE WILL CONTINUE TO LIFT OVER THE AREA...FOLLOWED BY A VARIETY OF ADDITIONAL WEAK SHORT WAVES...THROUGH TONIGHT. MODEST INSTABILITY REMAINS IN PLACE BUT LITTLE TO NO SHEAR IS AVAILABLE SO EXPECT STORMS OVERALL TO REMAIN TAME AND RATHER PULSE. ON SATURDAY...SURFACE LOW LIFTS THROUGH NORTHEAST MONTANA DRAWING PLENTY OF MOISTURE AHEAD OF IT OVER MUCH OF NORTH DAKOTA. THE EXCEPTION WILL BE OVER THE SOUTHWEST WHERE A DRYLINE WILL SETUP WITH FALLING DEWPOINTS AND SOUTHWESTERLY WINDS. TIMING OF CONVECTION DEVELOPING WILL BE TRICKY GIVEN THE VARIETY OF SHORT WAVES LIFTING THROUGH THE AREA. INSTABILITY INCREASES QUITE A BIT WITH THE INCREASING MOISTURE WHICH WILL COMBINE WITH MODEST SHEAR TO BRING A MARGINAL SEVERE THREAT OVER CENTRAL INTO NORTHWESTERN NORTH DAKOTA. LARGE HAIL WILL BE THE MAIN THREAT. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 224 PM CDT FRI JUL 10 2015 THE LONG TERM WILL REMAIN ACTIVE SATURDAY THROUGH THE NEXT WEEK. SOUTHWEST FLOW ALOFT OVER THE WESTERN US WILL REMAIN OVER THE NEXT WEEK. THIS WILL PUT NORTH DAKOTA IN A FAVORABLE POSITION TO RECEIVE MANY UPPER LEVEL SHORT WAVES. ONE SUCH UPPER LOW IS EXPECTED TO REACH THE NORTHERN PLAINS SATURDAY. WARM...MOIST AIR WILL SURGE NORTH AHEAD OF THIS WAVE. A RATHER WARM AND MUGGY SATURDAY/SUNDAY IS EXPECTED. MODELS ARE INDICATING VERY HIGH CAPE VALUES BUT LITTLE TO NO SHEAR. WITH VERY HIGH MOISTURE CONTENT THROUGHOUT THE ATMOSPHERE...VERY HEAVY RAIN IS POSSIBLE WITH ANY THUNDERSTORMS THAT DEVELOP. THE LATEST SPC SEVERE OUTLOOKS PLACE A MARGINAL THREAT FOR SATURDAY. MOST OF THE THUNDERSTORM ACTIVITY IS EXPECTED NORTH SUNDAY AND MONDAY. BY WEDNEDAY AND THURSDAY ANOTHER WAVE IS EXPECTED TO MOVE THROUGH AS A UPPER LEVEL RIDGE ACROSS THE SOUTH CENTRAL CONUS MOVES EAST. AT THIS TIME THE GFS/ECMWF INDICATE SCATTERED THUNDERSTORMS ARE POSSIBLE ACROSS ALL OF WESTERN AND CENTRAL NORTH DAKOTA AS THE TRACK OF THIS LOW SHOULD BE FURTHER SOUTH THAN THIS WEEKEND`S. TEMPERATURES SHOULD GENERALLY RANGE FROM THE MID 80S TO LOW 90S THROUGH THE NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1212 AM CDT SAT JUL 11 2015 VFR CONDITIONS AND CHANCES FOR ISOLATED THUNDERSTORMS ARE EXPECTED THROUGH THE TAF PERIOD. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AC SHORT TERM...JJS LONG TERM...AJ AVIATION...AC
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
133 AM EDT SAT JUL 11 2015 .SYNOPSIS... UNSETTLED AND WET PATTERN LINGERS INTO THE WEEKEND. A SERIES OF UPPER LEVEL DISTURBANCES WILL CROSS THE AREA UNDER NORTHWEST FLOW NEXT WEEK...KEEPING UNSETTLED CONDITIONS EACH DAY. && .NEAR TERM /THROUGH TODAY/... 1030 PM UPDATE... SEEING THE MCS/MCV TYPE SYS COMING TO FRUITION OVER SE OH AND NE KY OVER THE LAST HR. LAST FEW IR SATELLITE IMAGES BEAR THIS OUT ALONG WITH RADAR. 00Z NAM AND LAST FEW RUNS OF THE HRRR HAVE LATCHED ON TO THIS NOW THAT IT HAS DEVELOPED. AS SUCH...HAVE LEANED HEAVILY ON THESE MODELS FOR REMAINDER OF THE OVERNIGHT. THERE IS GROWING CONCERN OF A RENEWED FLASH FLOOD EVENT IN THE C LOWLANDS OVERNIGHT...OVER AREAS THAT HAVE BEEN HIT HARD THE PAST FEW DAYS. QPF AMOUNTS OF 1 TO 2 INCHES UNDER A SOMEWHAT NARROW BAND CAN BE EXPECTED ACROSS THE ROUTE 33 CORRIDOR AND INTO THE N MTNS. PREVIOUS DISCUSSION BELOW... UNSETTLED WEATHER CONTINUES...LIKE A BROKEN RECORD THAT WONT FALL OFF THE TURNTABLE. FRONTAL BOUNDARY ACROSS SOUTHERN HALF OF THE CWA AT 1730Z. HIGH PWS REMAIN ACROSS THE AREA...GENERALLY 1.6 TO 2 INCHES...ONCE AGAIN. UPPER SHORTWAVE PUSHING EAST OUT OF THE MIDWEST...IS HELPING TO GENERATE MORE SHOWERS AND THUNDERSTORMS. SOME WITH FLOODING RAINS. FRONTAL BOUNDARY WILL LIFT SLIGHTLY NORTH TODAY AS SHORTWAVE APPROACHES. SOME FLASH FLOODING HAS ALREADY BEEN REPORTED WITH STORMS THAT HAVE DEVELOPED...AND HAVE FLASH FLOOD WATCHES POSTED THROUGH SATURDAY MORNING. THESE MAY BE A LITTLE LONG IN DURATION...BUT WANTED TO ACCOUNT FOR THE DIFFERENCE IN MODEL TRENDS AND TIMING OVERNIGHT...AND WILL LIKELY BE DROPPED SOMETIME LATE TONIGHT. IN ADDITION...MCS ASSOCIATED WITH APPROACHING SHORTWAVE WILL AFFECT AT LEAST WESTERN ZONES THIS AFTERNOON. STILL SOME UNCERTAINTY AS TO HOW FAR EAST THE SEVERE THREAT WILL BE. HAVE A WATCH OUT FOR WESTERN/SOUTHERN ZONES UNTIL 4 PM. && .SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/... AN UPPER LEVEL RIDGE WILL BRING DRIER CONDITIONS TO THE AREA SATURDAY NIGHT INTO EARLY SUNDAY. THEN...MODELS BRING A SHORT WAVE AT H500 CROSSING THE AREA SUNDAY AFTERNOON THROUGH SUNDAY NIGHT. WITH SFC DEWPOINTS IN THE MID TO UPPER 60S...PWATS INCREASING TO AROUND 2 INCHES MODELS BRING A CONSIDERABLE AMOUNT OF QPF OVER THE AREA LATE SUNDAY INTO EARLY MONDAY. THEREFORE...INCREASE POPS TO TO HIGH CHANCE SUNDAY AND TO LIKELY SUNDAY NIGHT AND MONDAY. UNDER NORTHWEST FLOW ALOFT...ADDITIONAL UPPER LEVEL DISTURBANCES WILL KEEP UNSETTLED WEATHER THROUGH MONDAY NIGHT. ALTHOUGH THERE WILL BE A SLIGHT DECREASE IN MOISTURE WITH PWATS GOING BACK TO AROUND 1.5 INCHES MONDAY NIGHT. WITH THE WET SOIL CONDITIONS...LUSH VEGETATION...CLOUDS AND SHOWERS... TEMPERATURES WILL BE SEASONABLE BUT ALSO HUMID. THE POTENTIAL FOR FLOODING CONTINUES TO BE A CONCERN FOR THIS PERIOD. && .LONG TERM /TUESDAY THROUGH FRIDAY/... A SERIES OF UPPER LEVEL DISTURBANCES UNDER NORTHWEST FLOW ALOFT WILL CROSS THE AREA KEEPING THE PATTERN UNSETTLED THROUGH THE REMINDER OF THE WEEK WITH CHANCES FOR SHOWERS AND THUNDERSTORMS EACH DAY. ALLOWED CHANCE POPS ACROSS THE AREA DUE TO UNCERTAINTIES BY THE MODELS IN THE LONG PERIOD. THEREFORE...ALLOWED SLIGHT CHANCE POPS WEDNESDAY NIGHT ON. WITH THE GROUNDS ALREADY SATURATED...WILL HAVE TO CONTINUE MONITORING THE WEATHER CLOSELY EACH DAY DUE TO WATER CONCERNS. WENT WITH WPC THINKING WITH TEMPERATURES...SKY...AND POPS THROUGH THE PERIOD. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... GOING WITH THE LOW STRATUS ONCE THE SHOWERS PASS TO THE EAST OVER THE REMAINDER OF THE OVERNIGHT PERIOD. THIS WILL BRING MVFR TO IFR CONDITIONS...BUT SHOULD KEEP THE VISIBILITIES FROM GOING DOWN TOO FAR THIS MORNING. DRYING WILL TAKE PLACE AFTER 12Z TODAY...AND ONCE HEATING TAKES PLACE...EXPECTING SLOW IMPROVEMENTS OF THE CEILINGS...BUT COULD TAKE UNTIL 15-16Z TODAY TO REACH VFR. VFR THROUGH THE REMAINDER OF THE TAF PERIOD...AS MID TO HIGH LEVEL MOISTURE FROM THE NEXT SYSTEM COMING SHOULD KEEP FOG FROM BEING AN ISSUE. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY... FORECAST CONFIDENCE: LOW TONIGHT. ALTERNATE SCENARIOS: LOW STRATUS CLOUD FORMATION IS IN QUESTION. AFTER 06Z SUNDAY...IFR POSSIBLE IN THUNDERSTORMS SUNDAY. && WV...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR WVZ005>008- 013>018-024>030-033>039-046-047. OH...FLASH FLOOD WATCH UNTIL 8 AM EDT SATURDAY FOR OHZ087. KY...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR KYZ105. FLASH FLOOD WATCH UNTIL 8 AM EDT SATURDAY FOR KYZ101>103. VA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR VAZ003-004. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...FLASH FLOOD WATCH UNTIL 11 AM EDT THIS MORNING FOR WVZ005>008- 013>018-024>030-033>039-046-047. OH...FLASH FLOOD WATCH UNTIL 8 AM EDT THIS MORNING FOR OHZ087. KY...FLASH FLOOD WATCH UNTIL 11 AM EDT THIS MORNING FOR KYZ105. FLASH FLOOD WATCH UNTIL 8 AM EDT THIS MORNING FOR KYZ101>103. VA...FLASH FLOOD WATCH UNTIL 11 AM EDT THIS MORNING FOR VAZ003-004. && $$ SYNOPSIS...ARJ/SL NEAR TERM...SL/30 SHORT TERM...ARJ LONG TERM...JB/ARJ AVIATION...30
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
356 AM CDT SAT JUL 11 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 355 AM CDT SAT JUL 11 2015 MODELS CONTINUE TO BRING WEAK THERMAL SUPPORT FOR SHOWER AND THUNDERSTORM DEVELOPMENT EAST ACROSS THE AREA THIS MORNING. SHORT TERM MODELS SUCH AS THE HRRR AND HOP/WRF KEEP THE CONVECTION VERY SPOTTY AND THIS LOOKS REASONABLE. WILL KEEP POPS AT CHANCE FOR NOW AND ENHANCE AS DEVELOPMENT WARRANTS. THIS ACTIVITY SHOULD DECREASE TO THE EAST NORTHEAST THIS AFTERNOON AS CAPPING FROM INCREASINGLY WARM AIR SPREADS INTO THE AREA. BY LATE IN THE DAY THIS ACTIVITY...IF THERE IS ANY LEFT...SHOULD BE CONFINED TO THE FAR EASTERN PART OF THE AREA WITH SOME MINIMAL NEW DEVELOPMENT POSSIBLE. MEANWHILE...STRONG WARMING OVER THE WESTERN PART OF THE AREA MAY INCLUDE ENOUGH HEATING TO BREAK THE CAP FAR WEST LATE THIS AFTERNOON AS THE DRYLINE GETS CLOSER. THIS IDEA WAS DEEMED REASONABLE IN THE EARLIER FORECAST AND STILL LOOKS SO...BUT AGAIN ACTIVITY SHOULD BE PRETTY SPARSE. THE SURGE OF WARMING AND HEATING SHOULD TAKE TEMPERATURES UP TO THE 90S WEST...WITH INCREASINGLY HUMID 80S EAST. LOW CLOUDS WHICH WILL BE PREVALENT IN AREAS EAST THIS MORNING SHOULD HEAT OUT AND GENERALLY DECREASE LATE MORNING AND AFTERNOON. FOR TONIGHT WILL KEEP SOME CHANCE OF STORMS FAR EAST WITH THE STRONG INSTABILITY. OTHERWISE A WARM NIGHT IS IN STORE WITH LOW TEMPERATURES WITHING A COUPLE DEGREES OF 70 EVERYWHERE. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 355 AM CDT SAT JUL 11 2015 HEAT AT THE FOREFRONT OF MID RANGE CONCERNS. CAPPED ENVIRONMENT WILL BE IN PLACE WITH STRONG ELEVATED MIXED LAYER TRAPPING NEAR SURFACE MOISTURE QUITE EFFECTIVELY ACROSS MUCH OF THE AREA THROUGH THE DAY. LIKELIHOOD OF SOME CONVECTION TO OUR SOUTH AGAIN THIS EVENING WILL ACT TO MODIFY ENVIRONMENT TO SOME DEGREE...AND SOUTH TO SOUTHEAST FLOW NEAR THE SURFACE WILL REINFORCE PRESENCE OF BOUNDARY LAYER MOISTURE INTO THE AFTERNOON FROM THE JAMES VALLEY EASTWARD. EVENTUALLY...APPEARS AS IF THE SURFACE TROUGH WILL BE PUSHING INTO THE JAMES VALLEY OR A BIT EAST BY LATE SUNDAY AFTERNOON...AND OTHER THAN A BUFFER OF SLIGHTLY BETTER MIXING JUST TO THE EAST OF THIS... MIXING WILL BE QUITE CHALLENGED BY THE STRONG INVERSION. AS A RESULT...WILL PROBABLY NOT GET QUITE AS TOASTY FROM AROUND I29 EASTWARD...BUT STILL PLENTY WARM INTO THE LOWER 90S...WHILE AREAS WEST OF THE TROUGH ARE LIKELY TO FIND A FEW SPOTS REACHING THE CENTURY MARK...AS DEWPOINTS MIX GREATLY INTO THE 50S. EVEN WITH THE SLIGHTLY LOWER TEMPERATURE EXPECTATIONS...DEWPOINTS WILL SOAR WELL INTO THE 70S...AND WILL RESULT IN A LARGE AREA OF 100 TO 105 DEGREE AFTERNOON HEAT INDEX. JAMES VALLEY LOCATIONS WILL HAVE THE WORST EARLY AFTERNOON BEFORE START TO SEE MIXING LOWERING THE MOISTURE CONTENT. WITH THE LONG PERIOD SINCE LAST EXTREME HEAT AND THE NUMEROUS OUTDOOR ACTIVITIES ON THE WEEKEND...HAVE DECIDED TO ISSUE HEAT ADVISORY FROM THE JAMES VALLEY EASTWARD THROUGH THE AFTERNOON ON SUNDAY. NOT TOTALLY IMPOSSIBLE TO FIND A ROGUE HIGH BASED THUNDERSTORM TO START THE DAY...BUT SUCH A LOW CHANCE THAT HAVE KEPT CLEAR OF THE FORECAST. OTHERWISE...WAVE WILL BEGIN TO PUSH ACROSS THE MEAN UPPER RIDGE DURING SUNDAY AFTERNOON AND EVENING...AND START TO ERODE SOME OF THE WARMEST AIR ALOFT. REALLY HARD TO PICTURE THERE BEING ENOUGH LIFT TO BREAK RESIDUAL INVERSION EVEN AFTER FULL HEATING...WITH CIN LIKELY IN THE 50-150 J/KG RANGE FOR MOST LOCATIONS. OUTSIDE CHANCE THERE COULD BE A GOLDILOCKS LOCATION WHERE THE WEAKENING CAP AND FORCING ARE JUST RIGHT...BUT AT THIS POINT NOT WORTH CLUTTERING THE FORECAST WITH ISOLATED THREAT. HOWEVER...KEEP AWARE...AS THERE IS MORE THAN ENOUGH POTENTIAL INSTABILITY TO MAKE FOR A STRONGER STORM. PERHAPS A BIT BETTER CHANCE FOR THINGS TO COME TOGETHER OVER THE NORTHEASTERN CWA CLOSEST TO THE UPPER FORCING DURING THE EVENING...BUT SHOULD BE A PRETTY QUICKLY CLOSING WINDOW AS STRONGER FORCING MOVES QUICKLY PAST AND DEEPER DRYING ON WEST TO NORTHWEST FLOW SPREADS ACROSS THE AREA. NEAR SURFACE WINDS WILL DECOUPLE AND ALLOW THE SURFACE TO RECOVER QUITE A BIT IN THOSE FULLY MIXED AREAS...AND RETAIN SOME UPPER 60S DEWPOINT VALUES IN THE SOUTHEAST. ON MONDAY...AS SHOULD BE ANOTHER VERY WARM DAY...THE VERY HUMID CONDITIONS WILL BE RELAXED SOMEWHAT OVER A GOOD PORTION OF THE AREA...WITH HIGHEST READINGS EAST OF I 29 DURING THE MORNING HOURS. DEEPER MIXING SHOULD TAKE DEWPOINTS INTO THE 50S WEST TO LOWER TO MID 60S EAST DURING THE AFTERNOON...WITH WINDS AT 15 TO 25 MPH AT TIMES. THE HEAT INDEX WILL AGAIN CLIMB INTO THE 90S. WILL HAVE TO SEE IF WE GET ANOTHER INCREASE IN SMOKE BEHIND THE BOUNDARY AS IT PUSHES SOUTHWARD SUNDAY NIGHT/MONDAY...AS COULD IMPACT TEMPS A COUPLE DEGREES. THE EXTENDED RANGE FROM TUESDAY THROUGH FRIDAY WOULD SEEMINGLY BE A BIT MORE ACTIVE IN GENERAL...WITH RIDGE ACROSS THE NORTHERN PLAINS...BREACHED PERIODICALLY WITH SYSTEMS COMING OUT OF THE WEST TO SOUTHWEST FLOW ALOFT. A COMMON FEATURE IN MODELS IS WAVE AROUND WEDNESDAY...AND HAVE MAINTAINED HIGHER PRECIP CHANCES WITH THIS FEATURE. TEMPS SHOULD REMAIN FROM NORMAL TO SLIGHTLY ABOVE NORMAL... BUT WILL HAVE TO WATCH TO SEE IF SLIGHTLY MORE AMPLIFIED SOLUTION IN ECMWF COULD KEEP A BETTER BACKDOOR BOUNDARY AROUND MIDWEEK. ANOTHER WAVE HAS PROXIMITY TO THE END OF THE FORECAST CYCLE...BUT DRASTICALLY DIFFERING TIMING IN GREATER ENSEMBLE OF SOLUTIONS FOR SURFACE REFLECTION. WATCHING FOR ANOTHER EASTWARD SURGE IN WARMER AIR AHEAD OF THIS WAVE...WHICH COULD BE ON THE WAY FOR LATE WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1051 PM CDT FRI JUL 10 2015 FOR THE 06Z TAF SET...STILL CONCERNED ABOUT MVFR DEVELOPMENT LATE TONIGHT THROUGH MID MORNING SATURDAY DUE TO TRAPPED MOISTURE BELOW THE THERMAL INVERSION. IN FACT EVEN CURRENTLY...THERE IS HIGHER BASED STRATUS AROUND SIOUX CITY AND IN EASTERN NEBRASKA JUST INSIDE THE VFR CATEGORY. SO THERE IS ABUNDANT LOW LEVEL MOISTURE. NOT A HUNDRED PERCENT CONFIDENT IN THIS SCENARIO HOWEVER...SO KEPT THE CEILINGS AS BROKEN AND CERTAINLY DID NOT WANT TO GO IFR AT THIS TIME. AS FAR AS PRECIPITATION...CONTINUED TO LEAVE THE TAF SET DRY BELIEVING THAT TSRA CHANCES ARE NOT WIDESPREAD ENOUGH AT THIS TIME TO INCLUDE A MENTION IN THE TAFS. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR SDZ038>040- 053>056-059>062-065>071. MN...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR MNZ071-072-080- 081-089-090-097-098. IA...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR IAZ001>003- 012>014-020>022-031-032. NE...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR NEZ013-014. && $$ SHORT TERM... LONG TERM...CHAPMAN AVIATION...MJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
340 AM CDT SAT JUL 11 2015 .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 339 AM CDT SAT JUL 11 2015 REGIONAL RADARS THIS MORNING SHOWING SOME CONVECTION THIS MORNING OVER NORTHERN MISSOURI WITH ANOTHER AREA OF CONVECTION OVER EASTERN NEBRASKA. THIS ACTIVITY IS NORTH OF A WARM FRONT THAT EXTENDS ACROSS NORTHERN KANSAS AND MISSOURI AND AHEAD OF A WEAK TROUGH OF LOW PRESSURE FROM KANSAS INTO NORTH DAKOTA. WATER VAPOR SATELLITE SHOWS ONE SHORT WAVE TROUGH OVER NEBRASKA AND KANSAS WITH ANOTHER OVER NORTH DAKOTA. THE TREND IN THE 11.00Z MODELS AND 11.03Z RAP IS FOR THE WAVE OVER NEBRASKA AND KANSAS TO FLATTEN OUT AS IT MOVES NORTHEAST INTO THE TOP PART OF THE RIDGE AXIS OVER THE CENTRAL PART OF THE COUNTRY. THE WAVE OVER NORTH DAKOTA WILL ALSO CONTINUE TO MOVE NORTHEAST INTO SOUTHERN CANADA THROUGH THE DAY. THE SURFACE WARM FRONT SHOULD LIFT SLOWLY TO THE NORTH WITH A GENERAL MODEL CONSENSUS OF IT REACHING ABOUT THE IOWA/MISSOURI BORDER. THIS WILL KEEP THE BEST MOISTURE TRANSPORT WELL SOUTH OF THE AREA TODAY AND SHOULD KEEP MOST OF THE RAIN TO THE SOUTH AS WELL. THE MESO MODELS SEEMED TO HAVE LATCHED ON TO THIS AS WELL WITH THE 11.00Z CR-NAM NEST...HI-RES ARW AND NMM KEEPING THE AREA DRY WHILE THE 11.00Z NAM12 AND 11.05Z HRRR STILL TRY TO BRING THE REMAINS OF SOME DEVELOPING CENTRAL IOWA CONVECTION INTO THE SOUTHERN SECTIONS FOR THIS MORNING. BASED ON ALL THESE SOLUTIONS...HAVE TRENDED THE RAIN CHANCES DOWN FOR TODAY WITH ABOUT A 20 PERCENT CHANCE ACROSS THE NORTH TO AT MOST A 40 PERCENT CHANCE IN THE SOUTH. THESE COULD STILL BE TOO HIGH AS IT COULD END UP BEING TOTALLY DRY NORTH OF THE IOWA/MINNESOTA BORDER. UPPER LEVEL HEIGHTS SHOULD BUILD A LITTLE BIT OVER THE REGION TONIGHT AS THE SHORT WAVE TROUGHS MOVE OFF TO THE EAST. THE WARM FRONT WILL CONTINUE TO LIFT SLOWLY NORTH TAKING ON A MORE NORTHWEST TO SOUTHEAST ORIENTATION FROM A DEVELOPING AREA OF LOW PRESSURE OVER NORTH DAKOTA INTO CENTRAL ILLINOIS. THE NAM REALLY RAMPS UP THE MOISTURE TRANSPORT INTO THIS BOUNDARY AROUND 06Z SUNDAY AND BREAKS OUT CONVECTION NORTH OF THE BOUNDARY AND ACROSS THE AREA. THE 11.00Z GFS SOMEWHAT HINTS AT THIS AS WELL WHILE THE 11.00Z ECMWF KEEPS THE BOUNDARY FARTHER SOUTH AND MOST OF THE RAIN TO THE SOUTH AS WELL. THE HI-RES NMM IS SIMILAR TO THE NAM WHILE THE HI-RES ARW IS COMPLETELY DRY FOR TONIGHT. CONCERNED THAT THE NAM IS TOO STRONG WITH THE MOISTURE TRANSPORT TONIGHT AND WILL ONLY CARRY A GENERAL 30 TO 40 PERCENT CHANCE ACROSS THE AREA. THE REAL ACTION AND BEST CHANCES FOR RAIN MAY COME SUNDAY NIGHT. A SHORT WAVE TROUGH IS EXPECTED TO COME OUT OF THE WEAKENING UPPER LEVEL LOW CURRENTLY OVER OREGON AND NEVADA. THIS WAVE SHOULD TOP THE UPPER LEVEL RIDGE AND THEN SLIDE SOUTHEAST ACROSS THE AREA SUNDAY NIGHT. THE GFS SUGGESTS THIS WAVE WILL PRODUCE SOME MODERATE PV ADVECTION IN THE 500-300 MB LAYER AS IT COMES ACROSS. THIS LIFT SHOULD BE AIDED BY SOME JET DYNAMICS FROM THE LEFT EXIT REGION OF THE 300 MB JET AS THIS COMES IN WITH THE SHORT WAVE TROUGH. THE WARM FRONT SHOULD CONTINUE TO EDGE NORTH EXTENDING FROM EASTERN NORTH DAKOTA INTO ILLINOIS WITH THE GFS SHOWING WEAK TO MODERATE FRONTOGENESIS IN THE 1000-850 MB LAYER NORTH OF THE FRONT. AS THE SHORT WAVE TROUGH APPROACHES...A CONVECTIVE COMPLEX SHOULD FROM LATE SUNDAY AFTERNOON OVER THE EASTERN DAKOTAS AND THEN SLIDE SOUTHEAST THROUGH THE NIGHT ALONG AND NORTH OF THE WARM FRONT. THERE SHOULD STILL BE AMPLE CAPE AVAILABLE FOR THE STORMS TO WORK WITH AS THEY MOVE INTO THE AREA. THE GFS SUGGESTS UP TO 2500 J/KG OF ML CAPE SUNDAY EVENING ONLY DROPPING OFF TO 1500 J/KG DURING THE OVERNIGHT HOURS. UP TO 40 KNOTS OF SHEAR SHOULD MOVE IN AHEAD OF THE SHORT WAVE TROUGH WITH THIS BEING PRIMARILY IN THE 0-3 KM LAYER. THIS WILL PRESENT THE OPPORTUNITY FOR A NOCTURNAL MCS TO ROLL ACROSS THE AREA WITH A SEVERE WIND THREAT. HAIL DOES NOT LOOK TO BE MUCH OF THREAT WITH WARM CLOUD DEPTHS ON THE ORDER OF 3.5 TO 4 KM...BUT THERE SHOULD BE SOME GOOD RAINFALL RATES AND LOCALLY HEAVY RAINS. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 339 AM CDT SAT JUL 11 2015 THE UPPER LEVEL RIDGE SHOULD BRIEFLY BUILD BACK OVER THE REGION EARLY IN THE WEEK BEFORE FLATTENING OUT WITH ZONAL FLOW OVER THE UPPER MIDWEST. THIS PATTERN LOOKS TO BE A DIRTY FLOW WITH THE POTENTIAL FOR SEVERAL SHORT WAVE TROUGHS TO BE EMBEDDED IN THE FLOW AND COME ACROSS THE REGION. DECENT AGREEMENT IN TIMING OF A WAVE FOR WEDNESDAY BETWEEN THE ECMWF AND GFS...BUT DIFFERENCES IN STRENGTH WITH THE GFS BEING STRONGER. AFTER THAT...CONSIDERABLE DIFFERENCES IN HOW AN UPPER LEVEL LOW COMING ACROSS SOUTHWEST CANADA IS HANDLED. THE GFS OPENS THIS SYSTEM UP AND BRINGS IT TOWARD THE AREA BY THE END OF THE WEEK WHILE THE ECMWF KEEPS IT AS A CLOSED LOW HOLDING IT BACK WITH RIDGING OVER THE REGION. WITH ALL THE UNCERTAINTY...WILL STAY WITH GENERAL 20 TO 40 PERCENT CHANCES THROUGH THE PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1145 PM CDT FRI JUL 10 2015 MAJORITY OF CONVECTION THROUGH THE PERIOD EXPECTED TO REMAIN SOUTH OF TAF AIRFIELDS WITH ONLY A 20 TO 40 PERCENT CHANCE FOR THUNDERSTORMS. WILL KEEP 11.06Z TAFS DRY FOR NOW GIVEN COVERAGE/ TIMING UNCERTAINTY. ASSUMING RUNWAYS REMAIN DRY...ANY CEILINGS THAT DO DEVELOP SHOULD BE ABOVE 3000 FT AGL...ALTHOUGH WILL NEED TO WATCH NORTHWARD EXTENT OF POTENTIAL MVFR DECK ASSOCIATED WITH PRECIPITATION THAT DEVELOPS FARTHER SOUTH. LIGHT SOUTH-SOUTHEAST WIND WILL PERSIST AT KRST/KLSE THROUGH THE PERIOD. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...04 LONG TERM...04 AVIATION...ROGERS
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
326 AM CDT SAT JUL 11 2015 .TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM. 500 MB RIDGE AXIS AND SFC HIGH PRESSURE EXITS THE REGION EARLY SATURDAY MORNING AS A SHORTWAVE TROUGH AND LOW LEVEL WARM AIR ADVECTION ALONG A WARM FRONT MAKES ITS WAY INTO THE REGION. MAINLY HIGH CLOUDS IN THE AREA AHEAD OF THE SHORTWAVE. SOME -SHRA CAN BE SEEN IN SOUTHEAST IOWA AT 08Z SATURDAY...MOVING NORTHEAST AHEAD THE LOW LEVEL BAROCLINIC ZONE. HIGHS SATURDAY LOOK TO BE NEAR 80F ACROSS S WI...AS 925 MB TEMPS ARE PROGGED TO BE NEAR 20C BY THE GFS. 925 MB TEMPERATURES WILL ONLY INCREASE FROM THERE AS WARM FRONT TRANSLATES NORTHEAST. 11.06 HRRR MESO MODEL IS SHOWING THE BULK OF THE PRECIPITATION DURING THE DAY SATURDAY TO BE SOUTH OF THE WI/IL BORDER AS THE HRRR IS PROGGING AN MCV DEVELOPING ACROSS N IL. THIS IS INDICATED IN THE GFS MODEL AS WELL...KEEPING THE STRONGEST MID-LEVEL SUPPORT SOUTH AS ISENTROPIC OMEGA VALUES REACH NEARLY 9 UBAR/S IN THE GFS. SO...REDUCED THE POPS DURING THE DAY SATURDAY. THE BEST CHANCES OF PRECIPITATION WILL BE SATURDAY NIGHT AS THE BEST WARM AIR ADVECTION AND INSTABILITY AXIS REACHES S WI. KEPT LIKELY POPS AS BETTER 850-700 MB FRONTOGENETICAL FORCING AND 850-700 MB Q- VECTOR CONVERGENCE CREEPS INTO THE REGION DURING THIS TIME. THERE IS A MARGINAL RISK FOR SEVERE WEATHER SOUTHWEST OF A JANESVILLE TO CROSS PLAINS TO LOGANVILLE LINE. GOOD INSTABILITY WILL DEVELOP IN THE EVENING AND OVERNIGHT HOURS SATURDAY INTO SUNDAY AS THE LOW LEVEL WAA COMES IN. MOST UNSTABLE CAPE VALUES ARE PROGGED TO REACH 2500+ J/KG ACCORDING TO THE GFS...WHILE THE NAM AND ECMWF ARE SHOWING MUCAPE ONLY AOA 1000 J/KG. .SUNDAY - CONFIDENCE...MEDIUM GRADUAL BUILDING OF HEIGHTS WITH ONE SHORTWAVE EXITING THE WESTERN GREAT LAKES REGION. GFS BLOWS UP ANOTHER ONE WITHIN THE BUILDING HEIGHTS REGIME BUT THIS APPEARS TO BE ERRONEOUS WITH OTHER MODELS SHOWING A CLEANER BUILDUP OF THE MID LEVEL RIDGE AXIS. MODELS SHOW SOME LINGERING SHRA/PSBL TSRA PRIOR TO 18Z WITH INFLUENCE OF THE DEPARTING WAVE AND 850/925 BAROCLINICITY. THE 850 FRONT SHIFTS FURTHER NE WITH 925 TEMPS REALLY SOARING THOUGH THE 12Z ECMWF HANGS ONTO THIS BOUNDARY LONGER WHICH SHOWS A COOLER REGIME THAN WHAT THE NAM/GFS IMPLIES. THE GFS SOUNDINGS SHOW CAPES BUILDING UP TO 3000 J/KG WITH INVERSION JUST UNDER 5K FEET. SOME AREAS SEEING SIGNIFICANT CIN DEVELOPING. LIFT BECOMES LESS DISCERNIBLE IN THE AFTERNOON NORTHWARD SHIFT OF WARM FRONT AND ANY UPPER FORCING QUESTIONABLE GIVEN THE PROGGD ERRONEOUS VORT BULLSEYE ON THE GFS. WILL GO WITH TEMPS WELL INTO THE 80S WITH SOME ONSHORE COOLING EFFECTS IN THE EAST. .SUNDAY NIGHT INTO MONDAY - CONFIDENCE...MEDIUM EXPECTING AN MCS TO RIDE ALONG LOWER LEVEL BAROCLINICITY LATER SUNDAY NIGHT. UPPER LEVEL JET WILL BE FAVORABLY PLACED WITH LEFT FRONT QUADRANT AND MID LEVEL WAVE RIDING INTO THE UPPER MIDWEST. THE NAM AND GFS SHOW GREATEST WINDOW OF CONCERN BETWEEN 06-12Z. THE 12Z ECMWF WAS SHOWING A SLOWER SOLUTION WITH 12-18Z BEING MORE PRIME. THE LATEST ECMWF SHOWS A LITTLE QUICKER SOLUTION. AIRMASS WILL BE RATHER UNSTABLE THROUGH THE NIGHT. PER SPC DISC FOR SWODY2 THE CONVECTION AFFECTING SRN WI WILL HAVE EVOLVED INTO MORE OF A WIND EVENT AS THESE STORMS RIDE IN NW-SE. CONVECTIVE REDEVELOPMENT WILL HINGE ON HOW BOUNDARIES LAY OUT AFTER THE MORNING STORMS. MID LEVEL FLOW STILL CYCLONIC WITH 250 JET STILL POSITIONED TO OUR SOUTHWEST WITH DIVERGENCE STILL NOTED ACROSS THE AREA. IF AIRMASS CAN RELOAD LOOKING AT CAPE BUILDUP WITH AFTERNOON STORMS ASSOCIATED WITH SURFACE TROUGH...BUT AGAIN LOTS WILL DEPEND ON HOW AIRMASS SETS UP AFTER THE MORNING ACTIVITY. ATTM SPC SWODY3 IS KEYING ON THIS BEING MORE ROBUST FURTHER SOUTH OF OUR CWA PROBABLY MORE CO-LOCATED WITH THE OUTFLOW FROM EARLIER STORMS. .TUESDAY - CONFIDENCE...LOW ECMWF/NAM SHOW WEAK SURFACE TROUGH LINGERING WHILE THE GFS SHIFTS BOUNDARY TO OUR SOUTH WITH NE WINDS AND HIGH PRESSURE NOSING IN. SO NEED TO RETAIN SOME POPS FOR THE SLOWER SOLUTIONS WHICH INCLUDES THE NAM AS WELL. ECMWF SHOWS A FAIRLY POTENT WAVE ARRIVINGDURING PRIME TIME AS WELL. HOPEFULLY FUTURE MODEL RUNS WILL COME INTO BETTER AGREEMENT ON THIS. .TUESDAY NIGHT AND WEDNESDAY - CONFIDENCE...MEDIUM MODELS SHOW HIGH PRESSURE BUILDING IN WITH NE-E FLOW AND COOLER AIRMASS. .THURSDAY AND FRIDAY - CONFIDENCE...LOW THE 00Z ECMWF ESSENTIALLY KEEPS THE INFLUENCE OF THE HIGH IN PLACE THIS PERIOD AS NEXT TROUGH AND ASSOCIATED PRECIP HANGS OUT IN THE PLAINS. THE GFS IS MORE PROGRESSIVE AND SHOWS A MORE ACTIVE PERIOD WITH POTENTIALLY SEVERAL ROUNDS OF PRECIP. GIVEN THE DISPARITY WILL LEAN ON THE SUPERBLEND POPS FOR NOW. && .AVIATION/12Z TAFS/...VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH SATURDAY MORNING UNTIL LOWER LEVEL CLOUDS AND PERHAPS SOME -SHRA MOVE INTO THE REGION. A MID-LEVEL SHORTWAVE TROUGH WILL SWEEP IN TO THE AREA ALONG WITH A PUSH OF WARMER AIR IN THE 925-850 MB LAYER. BEST CHANCES OF PRECIPITATION WILL BE SATURDAY EVENING AND OVERNIGHT AS BETTER FORCING ARRIVES AT THAT TIME. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ TODAY/TONIGHT AND AVIATION...JTS SUNDAY THROUGH FRIDAY...COLLAR
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
840 AM MST SAT JUL 11 2015 .SYNOPSIS...LITTLE CHANGE IN THE WEATHER PATTERN IS FORECAST THE NEXT SEVERAL DAYS. DRY WEATHER WITH NEAR NORMAL TEMPERATURES ARE EXPECTED IN SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA...WITH A THREAT OF AFTERNOON AND EVENING MOUNTAIN THUNDERSTORMS IN EASTERN ARIZONA...GENERALLY EAST OF PHOENIX. && .DISCUSSION... TODAY AND TONIGHT...SOME BIG CHANGES HAVE OCCURRED IN THE PAST 24 HOURS WITH REGARDS TO THE DISTRIBUTION OF MONSOON MOISTURE. FOR THE PAST 2 DAYS MOST OF THE MOISTURE WAS CONTAINED IN SOUTHEAST AZ WITH THE DRY LINE WAVERING BETWEEN PHOENIX AND TUCSON. THIS MORNINGS PHOENIX SOUNDING NOW SHOWS THE CENTRAL DESERTS IN THE MONSOON SOUP...SO TO SPEAK. FOR EXAMPLE...THE 12Z FRIDAY PHOENIX SOUNDING SHOWED A PRECIP WATER (PW) VALUE OF 0.69 INCHES AND AN 800 MB DEWPOINT OF 0 DEGREES C. IN CONTRAST...ITS NOW 1.35 INCHES OF PW WITH AN 800 MB DEWPOINT OF 13 DEG C. MONSOON MOISTURE WILL CONTINUE TO SPREAD SLOWLY WEST AND NORTH THIS WEEKEND...COVERING THE ENTIRE STATE BY MONDAY. ADDITIONALLY...BOTH PHOENIX AND TUCSON SOUNDINGS SHOWED CONSIDERABLE ML C.A.P.E.(500-1000 J/KG)...WITH LOW CONVECTIVE TRIGGER TEMPS (GLOBE 78 DEG F... TUCSON 89 F...AND HILLTOP AT 5700 FEET 70 F)...AND SIGNIFICANT VERTICAL SHEAR PROFILES...BETTER IN SOUTHEAST AZ. AT THE SAME TIME HOWEVER...SATELLITE IMAGERY SHOWED A WEAK DISTURBANCE MOVING OUT OF NORTHEAST AZ FOLLOWED BY A SIGNIFICANT UPPER LEVEL ANTI-CYCLONIC CIRCULATION FEATURE CONNECTED TO THE SUBTROPICAL JET OFFSHORE NORTHERN BAJA. STRONG ANTI-CYCLONIC CIRCULATION TENDS TO STABILIZE THE ATMOSPHERE A BIT...BUT WORKING AGAINST STRONG AFTERNOON THERMODYNAMICS TODAY WITH A EARLY START TO MOUNTAIN CONVECTION. EVEN THOUGH THE POTENTIAL ENERGY HAS INCREASED OVER THE LOWER DESERTS BETWEEN PHOENIX AND CASA GRANDE...WE STILL THINK STORMS WILL BE RELEGATED TO THE HIGHER TERRAIN NORTHEAST THROUGH SOUTHEAST OF PHOENIX. PERHAPS EARLY EVENING CONVECTIVE OUTFLOWS ON THE LOWER DESERTS ARE POSSIBLE. ALSO BECAUSE OF THE MODERATE VERTICAL WIND SHEAR PROFILES...SOME CONVECTION IN SOUTHERN GILA COUNTY ZONE 24 MAY BECOME ORGANIZED WITH HAIL AND STRONG GUSTY SURFACE WINDS. OTHERWISE CURRENT FORECASTS LOOK OK. NO UPDATES PLANNED TODAY. .PREVIOUS DISCUSSION...511 AM MST... UNSEASONABLY STRONG UPPER LOW OVER NRN CA/WRN NV CONTINUED TO WEAKEN AND LIFT NEWD EARLY THIS MORNING...MEANWHILE THE SWLY FLOW AHEAD OF IT REMAINED STRONG ENOUGH OVER THE DESERT SOUTHWEST TO CONFINE MOISTURE AND CONVECTION TO FAR ERN AND SERN AZ...MAINLY AREAS EAST OF PHOENIX. IR IMAGERY AT 2 AM SHOWED CLEAR SKIES WEST OF PHOENIX WITH PARTLY CLOUDY SKIES PRESENT FROM PHOENIX EAST. A COUPLE OF INTERESTING THINGS TO NOTE...DESPITE THE CONTINUED PRESENCE OF RELATIVELY DRY SOUTHWEST FLOW ALOFT OVER THE AREA AS SEEN IN THE LATEST 00Z PLOT DATA...MOISTURE DID INCREASE IN THE PHOENIX AREA DURING THE DAY YESTERDAY AND THE PHOENIX RAOB SHOWED PWAT UP TO 1.35 INCHES...WHICH WAS HIGHER THAN TUCSON WHICH REPORTED 1.21 INCHES. ALSO...FRI EVENING SURFACE DEWPOINTS OVER THE CENTRAL DESERTS HAD CLIMBED INTO THE LOW TO MID 50S...A RISE OF MORE THAN 20 DEGREES OVER THE PAST 24 HOURS. SO...DESPITE THE SOUTHWEST FLOW ALOFT WITH A VERY LAMINAR UPPER STREAMLINE FIELD AND NO SIGNIFICANT DISTURBANCES MOVING THROUGH THE FLOW...AROUND MIDNIGHT ISOLATED SHOWERS/STORMS STARTED TO DEVELOP OVER THE NORTH VALLEY...NEAR NEW RIVER...AND THEY MOVED QUICKLY TO THE NORTH/NORTHEAST. LATEST HRRR SUGGESTS THESE STORMS WILL WEAKEN AND MOVE OUT OF THE AREA WITHIN THE NEXT 1-2 HOURS LEAVING PARTLY CLOUDY OR MOSTLY CLEAR SKIES BEHIND FOR THE REST OF TONIGHT. FOR THE WEEKEND GUIDANCE REMAINS CONSISTENT THAT THE GRADUALLY WEAKENING TROFFING TO OUR NORTHWEST WILL ALLOW THE MAIN UPPER HIGH TO BUILD BACK WESTWARD...ALLOWING HEIGHTS TO RISE AND TEMPS TO CLIMB BACK TOWARDS NORMAL READINGS. STILL...THE MAIN HIGH CENTER REMAINS SUPPRESSED WELL TO THE EAST/SOUTHEAST OF ARIZONA AND AS SUCH STEERING FLOW REMAINS SOUTH/SOUTHWESTERLY. AS SUCH WE ARE STILL EXPECTED CONVECTION TO BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX...MAINLY AREAS OF SOUTHERN GILA COUNTY AS WELL AS EASTERN PORTIONS OF ZONE 28 ACROSS NORTHWEST PINAL COUNTY. ALL AREAS WEST OF MARICOPA COUNTY SHOULD STAY GENLY CLEAR WITH POPS LOW SINGLE DIGITS OR ZERO. AS FOR THE UPCOMING WORK WEEK...MONDAY THROUGH FRIDAY...GUIDANCE INCLUDING THE GFS AND ECMWF CONTINUE TO SUGGEST THAT TROFFING TO OUR NORTHWEST...OVER THE NORTHWESTERN STATES...WILL REMAIN STRONG ENOUGH TO KEEP THE MAIN UPPER HIGH SUPPRESSED TO OUR EAST AND SOUTHEAST. THIS WILL RESULT IN A CONTINUED SOUTHWESTERLY FLOW ACROSS MOST OF OUR AREA THROUGH THE PERIOD. MOISTURE/INSTABILITY/CAPE WILL BE MINIMAL FROM PHOENIX WESTWARD EACH DAY AND CONVECTION WILL REMAIN CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST AND SOUTHEAST OF PHOENIX. WE ARE LOOKING AT A VERY LOW GRADE MONSOON FOR THE DURATION OF THE FORECAST PERIOD. HIGH TEMPERATURES WILL CLIMB SLIGHTLY ABOVE NORMAL EACH DAY WITH HOTTER DESERTS REACHING NEAR 110 DEGREES. DESPITE H5 HEIGHTS STAYING MOSTLY AT OR BELOW 591DM EACH DAY...THE DRIER AIR AND SUNNY AFTERNOONS WILL ALLOW TEMPS TO RISE A BIT ABOVE SEASONAL NORMALS EACH DAY. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... INCREASED MID AND HIGH CLOUDS WILL BE PRESENT THROUGH MUCH OF THE DAY BEFORE GRADUALLY CLEARING TONIGHT. WILL AGAIN SEE SOME ISOLATED SHOWERS AND THUNDERSTORMS TODAY ACROSS HIGHER TERRAIN AREAS OF CENTRAL AND EASTERN ARIZONA...BUT STAYING AWAY FROM THE PHOENIX TERMINALS. LIGHT AND DIURNALLY DRIVEN WINDS WILL BE THE RULE THROUGH THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... MONDAY THROUGH FRIDAY... THE UPPER LEVEL FLOW PATTERN WILL SHIFT SLIGHTLY AS THE SUB-TROPICAL HIGH SHIFTS WESTWARD AND REESTABLISHES ITSELF JUST TO THE EAST OF THE DESERT SOUTHWEST NEXT WEEK. THIS WILL LEAD TO WARMING TEMPERATURES AND LIKELY AT LEAST SOME MOISTURE RETURN INTO EASTERN AND POSSIBLY CENTRAL ARIZONA. THUNDERSTORM CHANCES WILL BE LIMITED TO HIGHER TERRAIN LOCATIONS NORTH AND EAST OF PHOENIX. AFTERNOON MINIMUM HUMIDITY LEVELS IN A 10-15 PERCENT RANGE WILL BE PRESENT ACROSS THE LOWER DESERTS THROUGHOUT THE WEEK. WINDS WILL BE BREEZY AND MOSTLY OUT OF THE SOUTHWEST EACH AFTERNOON WITH GUSTS UP TO 20 MPH. && .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...VASQUEZ/CB AVIATION...KUHLMAN FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
511 AM MST SAT JUL 11 2015 .UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS... && .SYNOPSIS...LITTLE CHANGE IN THE WEATHER PATTERN IS FORECAST THE NEXT SEVERAL DAYS. DRY WEATHER WITH NEAR NORMAL TEMPERATURES ARE EXPECTED IN SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA...WITH A THREAT OF AFTERNOON AND EVENING MOUNTAIN THUNDERSTORMS IN EASTERN ARIZONA...GENERALLY EAST OF PHOENIX. && .DISCUSSION... UNSEASONABLY STRONG UPPER LOW OVER NRN CA/WRN NV CONTINUED TO WEAKEN AND LIFT NEWD EARLY THIS MORNING...MEANWHILE THE SWLY FLOW AHEAD OF IT REMAINED STRONG ENOUGH OVER THE DESERT SOUTHWEST TO CONFINE MOISTURE AND CONVECTION TO FAR ERN AND SERN AZ...MAINLY AREAS EAST OF PHOENIX. IR IMAGERY AT 2 AM SHOWED CLEAR SKIES WEST OF PHOENIX WITH PARTLY CLOUDY SKIES PRESENT FROM PHOENIX EAST. A COUPLE OF INTERESTING THINGS TO NOTE...DESPITE THE CONTINUED PRESENCE OF RELATIVELY DRY SOUTHWEST FLOW ALOFT OVER THE AREA AS SEEN IN THE LATEST 00Z PLOT DATA...MOISTURE DID INCREASE IN THE PHOENIX AREA DURING THE DAY YESTERDAY AND THE PHOENIX RAOB SHOWED PWAT UP TO 1.35 INCHES...WHICH WAS HIGHER THAN TUCSON WHICH REPORTED 1.21 INCHES. ALSO...FRI EVENING SURFACE DEWPOINTS OVER THE CENTRAL DESERTS HAD CLIMBED INTO THE LOW TO MID 50S...A RISE OF MORE THAN 20 DEGREES OVER THE PAST 24 HOURS. SO...DESPITE THE SOUTHWEST FLOW ALOFT WITH A VERY LAMINAR UPPER STREAMLINE FIELD AND NO SIGNIFICANT DISTURBANCES MOVING THROUGH THE FLOW...AROUND MIDNIGHT ISOLATED SHOWERS/STORMS STARTED TO DEVELOP OVER THE NORTH VALLEY...NEAR NEW RIVER...AND THEY MOVED QUICKLY TO THE NORTH/NORTHEAST. LATEST HRRR SUGGESTS THESE STORMS WILL WEAKEN AND MOVE OUT OF THE AREA WITHIN THE NEXT 1-2 HOURS LEAVING PARTLY CLOUDY OR MOSTLY CLEAR SKIES BEHIND FOR THE REST OF TONIGHT. FOR THE WEEKEND GUIDANCE REMAINS CONSISTENT THAT THE GRADUALLY WEAKENING TROFFING TO OUR NORTHWEST WILL ALLOW THE MAIN UPPER HIGH TO BUILD BACK WESTWARD...ALLOWING HEIGHTS TO RISE AND TEMPS TO CLIMB BACK TOWARDS NORMAL READINGS. STILL...THE MAIN HIGH CENTER REMAINS SUPPRESSED WELL TO THE EAST/SOUTHEAST OF ARIZONA AND AS SUCH STEERING FLOW REMAINS SOUTH/SOUTHWESTERLY. AS SUCH WE ARE STILL EXPECTED CONVECTION TO BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX...MAINLY AREAS OF SOUTHERN GILA COUNTY AS WELL AS EASTERN PORTIONS OF ZONE 28 ACROSS NORTHWEST PINAL COUNTY. ALL AREAS WEST OF MARICOPA COUNTY SHOULD STAY GENLY CLEAR WITH POPS LOW SINGLE DIGITS OR ZERO. AS FOR THE UPCOMING WORK WEEK...MONDAY THROUGH FRIDAY...GUIDANCE INCLUDING THE GFS AND ECMWF CONTINUE TO SUGGEST THAT TROFFING TO OUR NORTHWEST...OVER THE NORTHWESTERN STATES...WILL REMAIN STRONG ENOUGH TO KEEP THE MAIN UPPER HIGH SUPPRESSED TO OUR EAST AND SOUTHEAST. THIS WILL RESULT IN A CONTINUED SOUTHWESTERLY FLOW ACROSS MOST OF OUR AREA THROUGH THE PERIOD. MOISTURE/INSTABILITY/CAPE WILL BE MINIMAL FROM PHOENIX WESTWARD EACH DAY AND CONVECTION WILL REMAIN CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST AND SOUTHEAST OF PHOENIX. WE ARE LOOKING AT A VERY LOW GRADE MONSOON FOR THE DURATION OF THE FORECAST PERIOD. HIGH TEMPERATURES WILL CLIMB SLIGHTLY ABOVE NORMAL EACH DAY WITH HOTTER DESERTS REACHING NEAR 110 DEGREES. DESPITE H5 HEIGHTS STAYING MOSTLY AT OR BELOW 591DM EACH DAY...THE DRIER AIR AND SUNNY AFTERNOONS WILL ALLOW TEMPS TO RISE A BIT ABOVE SEASONAL NORMALS EACH DAY. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... INCREASED MID AND HIGH CLOUDS WILL BE PRESENT THROUGH MUCH OF THE DAY BEFORE GRADUALLY CLEARING TONIGHT. WILL AGAIN SEE SOME ISOLATED SHOWERS AND THUNDERSTORMS TODAY ACROSS HIGHER TERRAIN AREAS OF CENTRAL AND EASTERN ARIZONA...BUT STAYING AWAY FROM THE PHOENIX TERMINALS. LIGHT AND DIURNALLY DRIVEN WINDS WILL BE THE RULE THROUGH THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... MONDAY THROUGH FRIDAY... THE UPPER LEVEL FLOW PATTERN WILL SHIFT SLIGHTLY AS THE SUB-TROPICAL HIGH SHIFTS WESTWARD AND REESTABLISHES ITSELF JUST TO THE EAST OF THE DESERT SOUTHWEST NEXT WEEK. THIS WILL LEAD TO WARMING TEMPERATURES AND LIKELY AT LEAST SOME MOISTURE RETURN INTO EASTERN AND POSSIBLY CENTRAL ARIZONA. THUNDERSTORM CHANCES WILL BE LIMITED TO HIGHER TERRAIN LOCATIONS NORTH AND EAST OF PHOENIX. AFTERNOON MINIMUM HUMIDITY LEVELS IN A 10-15 PERCENT RANGE WILL BE PRESENT ACROSS THE LOWER DESERTS THROUGHOUT THE WEEK. WINDS WILL BE BREEZY AND MOSTLY OUT OF THE SOUTHWEST EACH AFTERNOON WITH GUSTS UP TO 20 MPH. && .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...CB AVIATION...KUHLMAN FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
759 AM MDT SAT JUL 11 2015 .UPDATE... ISSUED AT 739 AM MDT SAT JUL 11 2015 SHOWERS AND THUNDERSTORMS ALREADY DEVELOPING TO OUR SOUTHWEST THIS MORNING WITH LIGHTNING ACTIVITY PICKING UP IN THE VICINITY OF LAKE POWELL ON EDGE ON WEAK WAVE LIFTING NORTHEAST. ECMWF AND RUC SEEMS TO HAVE THE BEST HANDLE ON THIS MINOR RIPPLE LIFTING IT NORTHEAST AND WEAKENING OVER THE NEXT FEW HOURS. A SECONDARY WAVE LOOKS TO SPIN UP AROUND NOON...WITH MORE ACTIVITY LIFTING ACROSS MESA COUNTY AND INTO THE NORTHWEST PORTIONS OF THE FORECAST AREA. HAVE ADJUST POPS TO FIT CURRENT SITUATION AND BOOSTED VALUES UP A BIT THIS AFTERNOON. NO OTHER CHANGES WERE MADE TO THE GRIDS. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 400 AM MDT SAT JUL 11 2015 FORECAST PWATS REMAIN SOMEWHAT HIGH TODAY WITH VALUES OF AN INCH OR JUST ABOVE FAVORED IN THE RAP AND NAM WHILE GFS AND SREF PUT VALUES BETWEEN .75 TO .9 INCHES. THE LOCATION OF THE HIGH PRESSURE OVER TX AND AND TROUGH OFF THE WEST COAST STILL LOOKS FAVORABLE FOR MOISTURE TO CONTINUE TO ADVECT IN FROM THE SOUTH. NAM12 AND GFS IN PRETTY GOOD AGREEMENT THAT CONVECTION WILL FIRE IN THE FOUR CORNERS AROUND NOON AND OVERSPREAD THE AREA TO THE NORTHEAST. THE JET STREAM IS LOCATED FROM SRN CALIF...UP THROUGH LAS VEGAS AND CENTRAL UTAH WHICH WILL INCREASE ASCENT AND ALSO DIVERGENCE ALOFT WHICH IS ALWAYS HELPFUL IN CONVECTION. STRONGER STORMS AND SHOWERS THAT FORM WILL BRING HEAVY RAIN...SMALL HAIL AND SOME GUSTY WINDS...SIMILAR TO WHAT WE`VE SEEN ALL WEEK. SOME CONVECTION WILL CONTINUE THROUGH MIDNIGHT WITH VERY ISOLD CONVECTION AFTER THAT. THE TRICKY PART OF THE FORECAST IS SUNDAY. THE NAM PAINTS AN ALMOST COMPLETELY DRY DAY FOR THE CWA WHILE THE GFS FAVORS THE SAN JUANS AND AREAS SOUTH FOR MORE PRECIP. NOT SOLD ON NAM AS AVAILABLE MOISTURE...THOUGH LOWER...WILL STILL REMAIN AND THOUGH THE MOST ENERGETIC PART OF THE JET STREAM SHIFTS TO THE PLAIN STATES...ENOUGH SUPPORT MAY ALLOW SOME RAIN TO FALL. WITH THAT IN MIND...KEPT SCHC CONVECTION IN FORECAST FOR QUITE A BIT OF THE FORECAST AREA. MIGHT BE A BIT MUCH BUT WE CAN TRIM THE FORECAST AS NEWER MODELS COME IN. TEMPS START TO RISE BUT WILL REMAIN BELOW CLIMO. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 400 AM MDT SAT JUL 11 2015 MODELS ASSERT THAT THE LARGE SCALE PATTERN WILL REMAIN LARGELY UNCHANGED DURING THE EARLY PART OF THE COMING WEEK. CONSEQUENTLY ...EXPECT THE MONSOONAL SURGE WILL CONTINUE AS SUBTROPICAL MOISTURE IS DRAWN NORTHEASTWARD ACROSS THE AREA BETWEEN HIGH PRESSURE OVER THE SOUTHERN PLAINS AND A TROUGH OF LOW PRESSURE OVER THE WEST COAST. THE MOISTURE LADEN AIR WILL FUEL MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS FAVORING THE MOUNTAINS. NOCTURNAL STORMS ARE POSSIBLE DURING THIS PERIOD AS MORE SUBTLE FEATURES NOT WELL HANDLED BY LARGE SCALE MODELS MAY COME INTO PLAY. MODELS POINT TO A SHIFT IN THE PATTERN AT MIDWEEK AS ENERGY EJECTED FROM THE WEST COAST TROUGH MOVES EASTWARD OVER THE NORTHERN ROCKIES FLATTENING THE RIDGE. AS THIS OCCURS HIGH PRESSURE OVER THE SOUTHERN PLAINS WILL EXPAND WESTWARD CUTTING OFF THE INFLUX OF MOISTURE. DRIER AIR IN WESTERLY FLOW WILL ERODE THE MOISTURE OVER THE AREA DURING THE LATTER PART OF THE WEEK BRINGING A DECREASE IN AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS AS EARLY AS WEDNESDAY. MODELS DIFFER IN TIMING WITH GFS FASTER WITH THIS EVOLUTION...BUT BY THE END OF THE WEEK MODELS WERE IN AGREEMENT WITH GREATLY REDUCED MOIST CONVECTION. TEMPERATURES WILL REMAIN SUPPRESSED BY CLOUDS AND SHOWER ACTIVITY DURING THE EARLY PART OF THE WEEK SO EXPECT BELOW NORMAL VALUES TO CONTINUE. DRIER AIR TRANSLATES INTO GREATER SOLAR INSOLATION DURING THE LATTER HALF OF THE COMING WEEK AND AFTERNOON HIGHS WILL TREND UPWARD AS RESULT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 400 AM MDT SAT JUL 11 2015 VFR CONDITIONS WILL PREVAIL ACROSS THE AREA BEFORE MIDDAY...THOUGH A WEAK DISTURBANCE UPSTREAM MAY GET A FEW SHOWERS AND THUNDERSTORMS STARTED OVER THE SAN JUAN/S PRIOR TO NOON. DAYTIME HEATING COMBINED WITH MONSOON MOISTURE WILL FUEL SCATTERED THUNDERSTORMS DURING THE AFTERNOON AND INTO THE EARLY EVENING. THIS ACTIVITY WILL RESULT IN AREAS OF MOUNTAIN OBSCURATION ALONG WITH OUTFLOW WINDS TO 40 MPH. CHANCES OF STORMS LOWERING CIGS BELOW ILS BREAKPOINTS ARE LOW WITH OUTFLOW WINDS IMPACTING AIRPORT OPERATIONS MORE LIKELY. SHOWERS AND THUNDERSTORMS WILL LARGELY DIMINISH AFTER SUNSET. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...NONE. UT...NONE. && $$ UPDATE...JDC SHORT TERM...TGR LONG TERM...NL AVIATION...NL
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1002 AM CDT SAT JUL 11 2015 .UPDATE... ISSUED AT 1000 AM CDT SAT JUL 11 2015 UPDATED THE FORECAST TO INCREASE THE RAIN CHANCES THIS MORNING AND REFINE SOME OF THE TRENDS. BULK OF THE OVERNIGHT CONVECTION IS CURRENTLY ACROSS THE SOUTHEAST HALF OF IOWA...ALTHOUGH IT IS ALSO SHOWING AN EASTWARD PROGRESSION AND WILL BE AFFECTING THE NORTHERN THIRD OF THE FORECAST AREA OVER THE NEXT FEW HOURS. ATTACHED WING OF SHOWERS EXTENDS SOUTHEAST AND HAS BEEN WEAKENING...BUT WILL BE AFFECTING EAST CENTRAL ILLINOIS THROUGH MIDDAY. LATEST HRRR TRYING TO DEVELOP ADDITIONAL CONVECTION ACROSS WEST CENTRAL ILLINOIS SHORTLY AFTER MIDDAY. SOME ENHANCEMENT IN THE CUMULUS IS CURRENTLY STARTING TO APPEAR ACROSS NORTHERN MISSOURI WHERE THERE IS SOME CLEARING...AND THIS IS LIKELY WHAT THE HRRR IS PICKING UP ON. HAVE CONTINUED WITH THE HIGHER POP`S ACROSS THE NORTHERN CWA WITH THE MCS...BUT MAY NEED TO BUMP UP THE SOUTHERN AREAS ONCE THE CONVECTIVE TRENDS CAN BE ESTABLISHED. && .SHORT TERM...(TODAY) ISSUED AT 334 AM CDT SAT JUL 11 2015 WARM FRONTAL BOUNDARY LIFTING ACROSS CENTRAL IL AND SHORTWAVE TROUGH PASSING THROUGH NORTHERN IL TODAY WILL BE THE FOCUS FOR THUNDERSTORM ACTIVITY THROUGH THE EARLY PART OF THE DAY AS SUBSTANTIAL MOISTURE ADVECTS INTO THE AREA CHARACTERIZED BY PRECIPITABLE WATER AROUND 2 INCHES AND DEWPOINTS INTO THE 70S. A FEW THUNDERSTORMS ALREADY DEVELOPING IN THE EARLY MORNING IN WEST CENTRAL IL AS A RESULT OF ELEVATED INSTABILITY. THE SHORTWAVE CURRENTLY APPEARS TIMED FOR LATE MORNING TO EARLY AFTERNOON...WITH A POTENTIAL GAP IN THUNDERSTORM ACTIVITY FOR MID AFTERNOON AS ANOTHER SHORTWAVE APPROACHES THE NORTHERN PORTION OF THE STATE FROM THE WEST...BRINGING HIGHER CHANCES AGAIN FOR LATE AFTERNOON/EARLY EVENING. THIS LATER ROUND OF STORMS COULD BE QUITE STRONG AS MLCAPE VALUES AROUND 2000-2500 J/KG ARE FORECAST TO DEVELOP BY 00Z OVER CENTRAL IL. 0-6 KM BULK SHEAR EXPECTED TO REMAIN ONLY AROUND 25 KTS. SEVERE WEATHER THREATS WILL BE POTENTIAL FOR LOCALIZED DAMAGING WIND GUSTS AND HAIL...FOR WHICH SPC HAS A MARGINAL (5%) RISK IN MUCH OF CENTRAL/NORTHERN IL. POPS TODAY GENERALLY RANGING FROM CHANCE TO LIKELY IN THE NORTHWESTERN PORTIONS OF THE CENTRAL IL FORECAST AREA...RANGING DOWN TO SLIGHT CHANCE IN THE SOUTHEAST TO REFLECT ABOVE REASONING. HIGH TEMPERATURES HAVE BEEN TRENDED DOWN A FEW DEGREES TO THE LOW TO MID 80S DUE TO PREVALENT CLOUD COVER AND SHOWERS/THUNDERSTORMS. .LONG TERM...(TONIGHT THROUGH FRIDAY) ISSUED AT 334 AM CDT SAT JUL 11 2015 MCS TO TRACK SE ACROSS CENTRAL/NORTHERN IL TONIGHT AND INCREASED CHANCES OF SHOWERS AND THUNDERSTORMS. SPC HAS MARGINAL RISK OF SEVERE STORMS NORTH OF I-70 FOR 5% RISK OF DAMAGING WINDS AND LARGE HAIL. FRONTAL BOUNDARY TO SET UP JUST NE OF CENTRAL IL NEXT FEW DAYS AND WILL HAVE DISTURBANCES TRACKING SE ALONG BOUNDARY BRINGING GOOD CHANCES OF SHOWERS AND THUNDERSTORMS WITH NOCTURNAL LOW LEVEL JET AND VERY UNSTABLE AIR MASS AIDING IN THUNDERSTORMS DEVELOPMENT. HEAVY RAINS ALSO POSSIBLE WITH PRECIPITABLE WATER VALUES NEAR 2 INCHES. WILL WET GROUND HAVE TRIMMED HIGHS A FEW DEGREES NEXT FEW DAYS BUT STILL HIGHS IN UPPER 80S TO AROUND 90F SUNDAY AND UPPER 80S/LOWER 90S MON. WITH DEWPOINTS CLIMBING INTO THE 70S AFTERNOON HEAT INDICES TO RISE TO 95-100F SUNDAY AFTERNOON AND 99-104F MONDAY AFTERNOON WHICH IS JUST SHY OF HEAT ADVISORY CRITERIA OF 105F. SPC SHOWS A SLIGHT CHANCE OF SEVERE STORMS SUNDAY AFTERNOON INTO SUNDAY NIGHT WITH ANOTHER MCS TRACKING SE FROM UPPER MS RIVER VALLEY SUNDAY NIGHT. MEANWHILE ENHANCED RISK OF SEVERE STORMS MONDAY AFTERNOON/EVENING FOR DAMAGING WINDS...LARGE HAIL AND POSSIBLE TORNADOES. VERY UNSTABLE AIRMASS WITH CAPES OF 3-4K J/KG SUNDAY AFTERNOON AND 4-6K J/KG MONDAY AFTERNOON. 00Z FORECAST MODELS CONTINUE TO SHOW AN ACTIVE WEATHER PATTERN OVER IL THROUGH MIDDLE AND LATER PART OF NEXT WEEK WITH DAILY CHANCES OF SHOWERS AND THUNDERSTORMS IN A WARM AND HUMID AIRMASS. SERIES OF SHORT WAVES TO RIDE OVER TOP OF UPPER LEVEL RIDGE (CENTERED OVER THE SOUTHERN PLAINS) THAT WILL TRACK NEAR IL WHICH IS IN WNW UPPER LEVEL FLOW. A COLD FRONT TO TRACK SE THROUGH IL SOMETIME NEXT WEEKEND AND CONTINUES CHANCES OF SHOWERS/THUNDERSTORMS. HIGHS IN THE 80S WITH SOUTHEAST IL NEAR 90 AT TIMES WHILE LOWS CLOSE TO MUGGY DEWPOINTS IN THE UPPER 60S TO MID 70S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 702 AM CDT SAT JUL 11 2015 MAINLY VFR CONDITIONS ACROSS CENTRAL IL TERMINALS THIS MORNING ALTHOUGH AREAS OF MVFR AND LOCALLY WORSE HAZE AND FOG TO CONTINUE UNTIL 13Z-14Z. LOOSELY ORGANIZED BANDS OF SHOWERS/THUNDERSTORMS LIFTING INTO CENTRAL IL THIS MORNING AS A WARM FRONT LIFTS THROUGH THE REGION...AND HAVE INCORPORATED VCTS AND TEMPO TSRA TO REFLECT TIMING OF THIS FEATURE FOR KPIA-KBMI-KSPI...USING HRRR MODEL GUIDANCE WHICH LOOKS RELATIVELY ON TRACK WITH THE 11Z RUN. AFTER THIS BAND...MODELS INDICATE MORE THUNDERSTORM ACTIVITY TRACKING IN FROM THE WEST THROUGH NORTHERN SITES KPIA-KBMI SO HAVE NOT BEEN ABLE TO TIME A CLEAR BREAK IN ACTIVITY THERE. AT OTHER SITES...INCORPORATED VCTS AND LOW VFR CEILINGS 20Z AND LATER AS MULTIPLE PERIODS OF THUNDERSTORMS POSSIBLE WITH LOW CONFIDENCE ON TIMING AT THIS TIME. WINDS SE 3-6 KTS BECOMING SSE 6-10 KTS AFTER 14Z. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEELHART SHORT TERM...ONTON LONG TERM...07 AVIATION...ONTON
AREA FORECAST DISCUSSION
NWS LINCOLN IL
702 AM CDT SAT JUL 11 2015 .SHORT TERM...(TODAY) ISSUED AT 334 AM CDT SAT JUL 11 2015 WARM FRONTAL BOUNDARY LIFTING ACROSS CENTRAL IL AND SHORTWAVE TROUGH PASSING THROUGH NORTHERN IL TODAY WILL BE THE FOCUS FOR THUNDERSTORM ACTIVITY THROUGH THE EARLY PART OF THE DAY AS SUBSTANTIAL MOISTURE ADVECTS INTO THE AREA CHARACTERIZED BY PRECIPITABLE WATER AROUND 2 INCHES AND DEWPOINTS INTO THE 70S. A FEW THUNDERSTORMS ALREADY DEVELOPING IN THE EARLY MORNING IN WEST CENTRAL IL AS A RESULT OF ELEVATED INSTABILITY. THE SHORTWAVE CURRENTLY APPEARS TIMED FOR LATE MORNING TO EARLY AFTERNOON...WITH A POTENTIAL GAP IN THUNDERSTORM ACTIVITY FOR MID AFTERNOON AS ANOTHER SHORTWAVE APPROACHES THE NORTHERN PORTION OF THE STATE FROM THE WEST...BRINGING HIGHER CHANCES AGAIN FOR LATE AFTERNOON/EARLY EVENING. THIS LATER ROUND OF STORMS COULD BE QUITE STRONG AS MLCAPE VALUES AROUND 2000-2500 J/KG ARE FORECAST TO DEVELOP BY 00Z OVER CENTRAL IL. 0-6 KM BULK SHEAR EXPECTED TO REMAIN ONLY AROUND 25 KTS. SEVERE WEATHER THREATS WILL BE POTENTIAL FOR LOCALIZED DAMAGING WIND GUSTS AND HAIL...FOR WHICH SPC HAS A MARGINAL (5%) RISK IN MUCH OF CENTRAL/NORTHERN IL. POPS TODAY GENERALLY RANGING FROM CHANCE TO LIKELY IN THE NORTHWESTERN PORTIONS OF THE CENTRAL IL FORECAST AREA...RANGING DOWN TO SLIGHT CHANCE IN THE SOUTHEAST TO REFLECT ABOVE REASONING. HIGH TEMPERATURES HAVE BEEN TRENDED DOWN A FEW DEGREES TO THE LOW TO MID 80S DUE TO PREVALENT CLOUD COVER AND SHOWERS/THUNDERSTORMS. .LONG TERM...(TONIGHT THROUGH FRIDAY) ISSUED AT 334 AM CDT SAT JUL 11 2015 MCS TO TRACK SE ACORSS CENTRAL/NORTHERN IL TONIGHT AND INCREASED CHANCES OF SHOWERS AND THUNDERSTORMS. SPC HAS MARGINAL RISK OF SEVERE STORMS NORTH OF I-70 FOR 5% RISK OF DAMAGING WINDS AND LARGE HAIL. FRONTAL BOUNDARY TO SET UP JUST NE OF CENTRAL IL NEXT FEW DAYS AND WILL HAVE DISTURBANCES TRACKING SE ALONG BOUNDARY BRINGING GOOD CHANCES OF SHOWERS AND THUNDERSTORMS WITH NOCTURNAL LOW LEVEL JET AND VERY UNSTABLE AIR MASS AIDING IN THUNDERSTORMS DEVELOPMENT. HEAVY RAINS ALSO POSSIBLE WITH PRECIPITATABLE WATER VALUES NEAR 2 INCHES. WILL WET GROUND HAVE TRIMMED HIGHS A FEW DEGREES NEXT FEW DAYS BUT STILL HIGHS IN UPPER 80S TO AROUND 90F SUNDAY AND UPPER 80S/LOWER 90S MON. WITH DEWPOINTS CLIMBING INTO THE 70S AFTERNOON HEAT INDICES TO RISE TO 95-100F SUNDAY AFTERNOON AND 99-104F MONDAY AFTERNOON WHICH IS JUST SHY OF HEAT ADVISORY CRITERIA OF 105F. SPC SHOWS A SLIGHT CHANCE OF SEVERE STORMS SUNDAY AFTERNOON INTO SUNDAY NIGHT WITH ANOTHER MCS TRACKING SE FROM UPPER MS RIVER VALLEY SUNDAY NIGHT. MEANWHILE ENHANCED RISK OF SEVERE STORMS MONDAY AFTERNOON/EVENING FOR DAMAGING WINDS...LARGE HAIL AND POSSIBLE TORNADOES. VERY UNSTABLE AIRMASS WITH CAPES OF 3-4K J/KG SUNDAY AFTERNOON AND 4-6K J/KG MONDAY AFTERNOON. 00Z FORECAST MODELS CONTINUE TO SHOW AN ACTIVE WEATHER PATTERN OVER IL THROUGH MIDDLE AND LATER PART OF NEXT WEEK WITH DAILY CHANCES OF SHOWERS AND THUNDERSTORMS IN A WARM AND HUMID AIRMASS. SERIES OF SHORT WAVES TO RIDE OVER TOP OF UPPER LEVEL RIDGE (CENTERED OVER THE SOUTHERN PLAINS) THAT WILL TRACK NEAR IL WHICH IS IN WNW UPPER LEVEL FLOW. A COLD FRONT TO TRACK SE THROUGH IL SOMETIME NEXT WEEKEND AND CONTINUES CHANCES OF SHOWERS/THUNDERSTORMS. HIGHS IN THE 80S WITH SOUTHEAST IL NEAR 90 AT TIMES WHILE LOWS CLOSE TO MUGGY DEWPOINTS IN THE UPPER 60S TO MID 70S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 702 AM CDT SAT JUL 11 2015 MAINLY VFR CONDITIONS ACROSS CENTRAL IL TERMINALS THIS MORNING ALTHOUGH AREAS OF MVFR AND LOCALLY WORSE HAZE AND FOG TO CONTINUE UNTIL 13Z-14Z. LOOSELY ORGANIZED BANDS OF SHOWERS/THUNDERSTORMS LIFTING INTO CENTRAL IL THIS MORNING AS A WARM FRONT LIFTS THROUGH THE REGION...AND HAVE INCORPORATED VCTS AND TEMPO TSRA TO REFLECT TIMING OF THIS FEATURE FOR KPIA-KBMI-KSPI...USING HRRR MODEL GUIDANCE WHICH LOOKS RELATIVELY ON TRACK WITH THE 11Z RUN. AFTER THIS BAND...MODELS INDICATE MORE THUNDERSTORM ACTIVITY TRACKING IN FROM THE WEST THROUGH NORTHERN SITES KPIA-KBMI SO HAVE NOT BEEN ABLE TO TIME A CLEAR BREAK IN ACTIVITY THERE. AT OTHER SITES...INCORPORATED VCTS AND LOW VFR CEILINGS 20Z AND LATER AS MULTIPLE PERIODS OF THUNDERSTORMS POSSIBLE WITH LOW CONFIDENCE ON TIMING AT THIS TIME. WINDS SE 3-6 KTS BECOMING SSE 6-10 KTS AFTER 14Z. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...ONTON LONG TERM...07 AVIATION...ONTON
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1012 AM EDT SAT JUL 11 2015 .UPDATE... THE NEAR TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 1012 AM EDT SAT JUL 11 2015 HIGH PRESSURE WILL SHIFT EAST OF THE REGION BY LATE DAY. AFTER THAT LOW PRESSURE WILL DEVELOP OVER THE PLAINS AND SLOWLY HEAD EAST...CAUSING VERY WARM HUMID AIR TO FLOW ACROSS OUR STATE. EVENTUALLY THE LOW PRESSURE SHOULD BECOME ASSOCIATED WITH A COLD FRONT...WHICH IS FORECAST TO CROSS THE HOOSIER STATE FROM TUESDAY INTO WEDNESDAY. FOR THURSDAY INTO FRIDAY HIGH PRESSURE IS EXPECTED TO TRAVERSE INDIANA FROM WEST TO EAST. THIS WILL CAUSE ANOTHER FLOW OF WARM HUMID AIR BY THE WEEKEND. && .NEAR TERM /REST OF TODAY/... ISSUED AT 1012 AM EDT SAT JUL 11 2015 PATCHY DENSE FOG HAS NOW ALL BUT BURNED OFF ACROSS THE REGION... WITH THE WELCOME SIGHT OF THE SUN AS WEAK HIGH PRESSURE DRIFTS SLOWLY EAST. 14Z TEMPS GENERALLY RANGE FROM THE UPPER 60S TO LOWER 70S. CLOUD DEBRIS ASSOCIATED WITH CONVECTION FROM CENTRAL ILLINOIS BACK INTO SOUTHERN IOWA ALREADY EXPANDING INTO THE WESTERN FORECAST AREA AND WILL DIMINISH SUNSHINE UNFORTUNATELY INTO THE AFTERNOON. AIRMASS OVER THE REGION IS QUITE A BIT MORE STABLE THAN AREAS FURTHER WEST...SO EXPECTATION IS THAT ONGOING STORMS OVER CENTRAL INDIANA WILL WEAKEN AS THEY APPROACH THE WABASH VALLEY AROUND MIDDAY. HRRR AND NMM-WRF BOTH HAVE A VERY GOOD HANDLE ON THIS THINKING AND WAS UTILIZED FOR POPS INTO THE AFTERNOON. WILL INTRODUCE SCHC POPS INTO THE NORTHERN HALF OF THE WABASH VALLEY BY 17Z WITH A SLOW EASTWARD EXPANSION THEREAFTER. STILL THINK BETTER CHANCE FOR CONVECTION WILL HOLD OFF UNTIL LATE AFTERNOON AT THE EARLIEST AND OVERNIGHT FOR MOST. INSTABILITY AND PRECIP WATER VALUES WILL INCREASE GRADUALLY BY LATE AFTERNOON AS THE REMNANT FRONTAL BOUNDARY APPROACHES...WITH HIGHEST VALUES RESIDING IN THE WABASH VALLEY BY LATE DAY. SOME UNCERTAINTY EXISTS IN HOW CONVECTION WILL REDEVELOP LATER ON OUT WEST WITH SOME HINTS AT INITIATION ACROSS NORTHEAST MISSOURI AND CENTRAL ILLINOIS ALONG THE INSTABILITY GRADIENT AND AT THE NOSE OF THE LOW LEVEL JET...WITH ADDITIONAL DEVELOPMENT DURING THE EVENING OVER NORTHERN ILLINOIS AIDED BY THE JET. STILL ANTICIPATE THIS ACTIVITY TO RIDE THE INSTABILITY GRADIENT AND REMNANT BOUNDARY INTO THE AREA TONIGHT WITH STRONG STORMS AND HEAVY RAIN POTENTIAL. LOWERED HIGH TEMPS SLIGHTLY WITH EXPECTED CLOUD COVERAGE LATER ON TODAY. ZONE AND GRID UPDATES OUT. && .SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/... ISSUED AT 250 AM EDT SAT JUL 11 2015 AS FOR SOME TIME...PRECIPITATION IS THE MAIN ISSUE. ALL MODELS HAVE THE CWA UNDER POSITIVE ADVECTION OF WET BULB POTENTIAL TEMPERATURE TONIGHT. THIS IS LIABLE TO FIRE A CONVECTIVE SYSTEM. THE MODELS REFLECT THIS FAIRLY WELL IN THEIR WET POPS. THE PRECIPITABLE WATER DOESNT LOOK QUITE ENOUGH FOR WIDESPREAD HEAVY RAIN AND A FLOOD WATCH TONIGHT. IT IS ENOUGH TO MENTION LOCALLY HEAVY RAIN. SUNDAY INTO TUESDAY NIGHT THINGS GET COMPLICATED. THERE IS A LOT OF DISAGREEMENT BETWEEN ON THE MODELS ON THE LOCATION OF SUBTLE FEATURES THAT WILL DRIVE CONVECTION. WITH THAT UNCERTAINTY...CHANCE POPS SEEM BEST MOST OF THE TIME. GIVEN THE UNCERTAINTY ABOUT POPS THERE IS ALSO UNCERTAINTY ABOUT TEMPERATURES. ON AVERAGE...A CONSENSUS FORECAST IS THE WAY TO GO IN SUCH SITUATIONS...SO AN CONSENSUS OF THE MAV AND MET WILL BE USED. AN EXCEPTION WILL BE MADE TUESDAY. SLIGHT CUTS WILL BE MADE. ITS HARD TO SEE MANY PLACES HITTING 90 GIVEN THE GROUND SHOULD BE QUITE WET. AN INTERESTING FEATURE ON MONDAY IS THE FORECAST CAPES NOT TOO FAR TO OUR WEST. THEY ARE LITERALLY THE HIGHEST I HAVE EVER SEEN. MONDAY MAY BE AN EXCITING DAY. && .LONG TERM /TUESDAY THROUGH FRIDAY/... ISSUED AT 227 AM EDT SAT JUL 11 2015 AN ACTIVE PATTERN WILL CONTINUE THROUGH THE LONG TERM AS AN UPPER RIDGE COVERING THE CENTRAL U.S. BROADENS AND FLATTENS OUT. THIS WILL ALLOW A SERIES OF WEAK UPPER WAVES TO MOVE THROUGH MAIN FLOW. MODELS ARE IN GOOD AGREEMENT ON THIS OVERALL PATTERN BUT DIFFER ON THE TIMING OF THESE PERTURBATIONS...AND THUS WILL CONTINUE WITH INITIALIZATION RESPONSE OF INCLUDING CHANCES FOR THUNDERSTORMS THROUGHOUT THE LONG TERM. THAT SAID STILL EXPECT DRY TIMES DURING THE LONG TERM...JUST UNABLE TO PIN THEM DOWN AT THIS POINT. INITIALIZATION KEEPS HIGH TEMPERATURES NEAR NORMAL IN THE MIDDLE 80S AND SAW NO REASON TO DEVIATE FROM THIS...ALTHOUGH NOT HIGH CONFIDENCE IN THESE GIVEN THE POTENTIAL FOR RAINFALL TO DECREASE THEM WHEN IT DEVELOPS. && .AVIATION /DISCUSSION FOR 111200Z TAF ISSUANCE/... ISSUED AT 647 AM EDT SAT JUL 11 2015 FOG AND LOW/OBSCURED CEILINGS SHOULD BURN OFF WITHIN AN HOUR OR TWO OF ISSUANCE AND VFR CONDITIONS WILL ENSUE FOR THE DAY. CHANCES FOR THUNDERSTORMS WILL ARRIVE THIS AFTERNOON AND EVENING...BUT LATEST GUIDANCE INDICATES THE BEST POTENTIAL WON/T BE ARRIVING UNTIL LATE. THUS PUSHED BACK ONSET OF VCTS BACK TO AROUND 3Z OR SO IN THE WEST AT KHUF AND OVERSPREAD THE OTHER SITES FROM THERE. TIME HEIGHT SECTIONS INDICATE GOOD POTENTIAL FOR RISING MOTION TO CONTINUE INTO SUNDAY MORNING SO ONCE VCTS STARTS WILL KEEP IT GOING FOR THE DURATION. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...JK/RYAN NEAR TERM...RYAN SHORT TERM...JK LONG TERM....CP AVIATION...CP VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1047 AM CDT SAT JUL 11 2015 .DISCUSSION...MORNING LCH SOUNDING SHOWING PWAT A FEW TENTHS BELOW THAT OF YESTERDAY MORNING. STILL SUFFICIENT MOISTURE FOR ISOLATED AFTERNOON CONVECTION. RADAR JUST NOW DEPICTING A FEW PINPOINT SHOWERS INLAND. FORECAST ON TRACK WITH LOW END POPS. NO UPDATE COMING. && .PREV DISCUSSION... /ISSUED 650 AM CDT SAT JUL 11 2015/ AVIATION...RIDGING WILL BUILD FROM THE MID LEVELS INTO THE UPPER LEVELS. ALTHOUGH HRRR IS SHOWING WIDELY SCATTERED TSTM ACTIVITY THIS AFTERNOON, WILL OPT TO NOT MENTION IN THE TAFS AS THE COVERAGE LOOKS TO BE ISOLATED FROM ALL THE CONVECTIVE INHIBITION. VFR. SWEENEY PREV DISCUSSION... /ISSUED 240 AM CDT SAT JUL 11 2015/ DISCUSSION... SFC HIGH PRESSURE CONTINUES RIDGING ACROSS THE GULF...WITH A S TO SE FLOW ACROSS THE REGION. RADAR SHOWING A FEW NOCTURNAL SHRA ACROSS THE COASTAL WATERS MOVING ASHORE ACROSS THE COASTAL PARISHES/COUNTIES AND DISSIPATING. LIMITED MOISTURE ALOFT AND FOCUS WILL LIMITED CONVECTION TO ISO DURING THE AFTERNOON HOURS...WITH THE ONGOING 20% STILL LOOKING GOOD FOR THE FORECAST. LOWER/MID 90S FOR HIGHS EXPECTED. THE FORECAST FOR NEXT WEEK LOOKS TO CONTINUE THE HOT AND DRY CONDITIONS DUE TO BUILDING HIGH PRESSURE AT THE SFC AND ALOFT. THE RIDGE WILL INTENSIFY A BIT TOWARDS MON-WED...LIMITING CONVECTION EVEN MORE...BUT TEMPS EXPECTED TO BUMP UP A COUPLE OF DEGREES. MODEL BLEND ONLY SHOWS A SLIGHT INCREASE IN MOISTURE TOWARDS FRI...WITH 20% EXPECTED. OTHERWISE...SLIGHTLY ABOVE NORMAL TEMPS EXPECTED THRU THE PERIOD...MOST NOTABLE FOR LOWS. DML MARINE... SURFACE HIGH PRESSURE RIDGING WESTWARD ACROSS THE NORTHWEST GULF OF MEXICO WILL CONTINUE TO PROVIDE A LIGHT SOUTHERLY FLOW OVER THE NEXT SEVERAL DAYS. && .PRELIMINARY POINT TEMPS/POPS... AEX 94 75 95 76 / 20 10 10 10 LCH 91 77 92 77 / 20 10 10 10 LFT 92 75 93 76 / 20 10 10 10 BPT 91 77 92 76 / 20 10 10 10 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...NONE. TX...NONE. GM...NONE. && $$ PUBLIC...23
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
650 AM CDT SAT JUL 11 2015 .AVIATION...RIDGING WILL BUILD FROM THE MID LEVELS INTO THE UPPER LEVELS. ALTHOUGH HRRR IS SHOWING WIDELY SCATTERED TSTM ACTIVITY THIS AFTERNOON, WILL OPT TO NOT MENTION IN THE TAFS AS THE COVERAGE LOOKS TO BE ISOLATED FROM ALL THE CONVECTIVE INHIBITION. VFR. SWEENEY && .PREV DISCUSSION... /ISSUED 240 AM CDT SAT JUL 11 2015/ DISCUSSION... SFC HIGH PRESSURE CONTINUES RIDGING ACROSS THE GULF...WITH A S TO SE FLOW ACROSS THE REGION. RADAR SHOWING A FEW NOCTURNAL SHRA ACROSS THE COASTAL WATERS MOVING ASHORE ACROSS THE COASTAL PARISHES/COUNTIES AND DISSIPATING. LIMITED MOISTURE ALOFT AND FOCUS WILL LIMITED CONVECTION TO ISO DURING THE AFTERNOON HOURS...WITH THE ONGOING 20% STILL LOOKING GOOD FOR THE FORECAST. LOWER/MID 90S FOR HIGHS EXPECTED. THE FORECAST FOR NEXT WEEK LOOKS TO CONTINUE THE HOT AND DRY CONDITIONS DUE TO BUILDING HIGH PRESSURE AT THE SFC AND ALOFT. THE RIDGE WILL INTENSIFY A BIT TOWARDS MON-WED...LIMITING CONVECTION EVEN MORE...BUT TEMPS EXPECTED TO BUMP UP A COUPLE OF DEGREES. MODEL BLEND ONLY SHOWS A SLIGHT INCREASE IN MOISTURE TOWARDS FRI...WITH 20% EXPECTED. OTHERWISE...SLIGHTLY ABOVE NORMAL TEMPS EXPECTED THRU THE PERIOD...MOST NOTABLE FOR LOWS. DML MARINE... SURFACE HIGH PRESSURE RIDGING WESTWARD ACROSS THE NORTHWEST GULF OF MEXICO WILL CONTINUE TO PROVIDE A LIGHT SOUTHERLY FLOW OVER THE NEXT SEVERAL DAYS. && .PRELIMINARY POINT TEMPS/POPS... AEX 94 75 95 76 / 20 10 10 10 LCH 91 77 92 77 / 20 10 10 10 LFT 92 75 93 76 / 20 10 10 10 BPT 91 77 92 76 / 20 10 10 10 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...NONE. TX...NONE. GM...NONE. && $$ AVIATION...11
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1018 AM EDT SAT JUL 11 2015 .UPDATE... ISSUED AT 1018 AM EDT SAT JUL 11 2015 ANOTHER IDEAL MORNING IN NORTHERN MI. SKIES ARE JUST ABOUT CLEAR...WITH SOME HIGH-BASED CU IN THE GD TRAV BAY REGION...AND IN PARTS OF CENTRAL UPPER MI. THIS IS ASSOCIATED WITH A SUBTLE WARM FRONT ADVANCING EAST NEAR MUNISING/ISQ...AND IS OCCURRING IN THE STEEP LAPSE RATES AT THE TOP OF YESTERDAYS MIXED LAYER. THERE IS STRONG INVERSION PRESENT ABOVE THIS. PER 12Z OBSERVED SOUNDINGS...700MB TEMPS ARE 9C AT APX...10C AT GRB. THIS IS NOT SURPRISING...GIVEN A 500MB SHORTWAVE RIDGE AXIS WILL BE DEAD OVERHEAD THIS AFTERNOON. SO IT WILL TAKE SOME SERIOUS WORK TO OVERCOME THIS CAP. THE 06Z/12Z NAM RUNS BOTH MANAGE TO DO SO...POPPING A STORM IN NE LOWER BY EARLY EVENING. IT MANAGES THIS WHERE CONVERGENCE IS MAXIMIZED (NE MONTMORENCY)...WHERE THE TWO DIFFERENT ORIENTATIONS OF THE LAKE HURON LAKE BREEZE INTERSECT AND MEET THE BACKGROUND SYNOPTIC SW WIND. AN 84/60 SURFACE PARCEL SURFACE PARCEL GENERATES ABOUT 800J/KG OF SBCAPE (AND DOES GET PAST THE CAP)...BUT MLCAPE IS STILL NEGLIGIBLE. AM A TOUCH MORE NERVOUS ABOUT A DRY FORECAST TODAY THAN YESTERDAY...BUT AT THIS POINT STILL BELIEVE DRY IS THE WAY TO GO. (NOTE THE SPC HRRR KEEPS US DRY.) A FAIRLY VIGOROUS CU FIELD WILL BUBBLE UP AWAY FROM THE GREAT LAKES AFTER MIDDAY...IN PARTICULAR NE LOWER AND NW CHIPPEWA CO. THAT WILL CERTAINLY NOT PREVENT A WARM AFTERNOON...WITH HIGHS FROM NEAR 80F TO THE MID 80S. && .NEAR TERM...(TODAY THROUGH TONIGHT) ISSUED AT 346 AM EDT SAT JUL 11 2015 ...TURNING UP THE HEAT JUST A LITTLE MORE... HIGH IMPACT WEATHER POTENTIAL: NONE. OVERVIEW: SUBTROPICAL UPPER LEVEL RIDGE CONTINUES TO BUILD ACROSS THE SRN GULF STATES...DOWNSTREAM OF TROUGHINESS ACROSS THE WESTERN CONUS. IN BETWEEN...A FAIR AMOUNT OF HEAT/HUMIDITY IS STREAMING FROM MEXICO UP THROUGH THE PLAINS AND ALONG THE FRONT RANGE OF THE ROCKIES THEN BACK INTO THE PAC NW...WHERE SEVERAL SHOWER/ THUNDERSTORM COMPLEXES ARE ONGOING. FURTHER EAST...HIGH PRESSURE REMAINS IN CONTROL FOR MUCH OF THE EASTERN CONUS...ALTHOUGH A FEW ROUNDS OF SHOWERS ARE ONGOING IN THE MIDWEST AND MID ATLANTIC STATES ALONG SOME SEMBLANCE OF A STALLED FRONT ACROSS THAT REGION. BUT ONCE AGAIN A QUIET AND MILD NIGHT ACROSS THE GREAT LAKES. PATTERN FORECAST: SUBTROPICAL RIDGE WILL CONTINUE TO BUILD WESTWARD TO BE CENTERED OVER TEXAS BY SUNDAY...AND RIDGE AXIS STRETCHING UP INTO THE UPPER MIDWEST. BUT THIS DOES SHIFT AXIS OF HEAT/HUMIDITY INTO THE PLAINS AND MIDWEST AND SETS UP A PROVERBIAL "RING OF FIRE" AND POTENTIAL FOR ONE OR MORE SHOWER/THUNDERSTORM COMPLEXES TO IMPACT THE REGION. MAIN FORECAST CONCERN IN THE SHORTER TERM IS WHETHER OR NOT NRN MICHIGAN CAN "CATCH" ANY PRECIP FROM ONE OF THESE SYSTEMS. SHORT ANSWER IS...PROBABLY NOT. TODAY...NO WORRIES AS SFC HIGH PRESSURE REMAINS THE DOMINATE PLAYER. TAKE YESTERDAYS HIGH TEMPS AND TAG ON ANOTHER FEW DEGREES AS WARMER AIR INCHES IT/S WAY OUT OF THE PLAINS INTO THE WESTERN GREAT LAKES EDGING H8 TEMPS ACROSS NRN MICHIGAN INTO THE 15C TO 16C RANGE BY EVENING. THIS SUGGESTS LOW TO MID 80S FOR MUCH OF THE CWA. BUT PER FORECAST SOUNDINGS WE WILL ALSO SEE ANOTHER ROUND OF SCT-BKN AFTERNOON CU SIMILAR TO YESTERDAY. CERTAINLY NOT OUT OF THE QUESTION THAT WE COULD POP A FEW SHOWERS ACROSS NE LOWER MICHIGAN WHERE LOW LEVEL CONVERGENCE WILL BE GREATEST (AND AS SUGGESTED BY THE 00Z NAM BUT WHICH AGAIN IS OVERDOING SFC DEWPOINTS/INSTABILITY). BUT LIKE YESTERDAY...WILL NOT BE ADDING ANY POPS TO THE FORECAST AT THIS POINT. TONIGHT...FORECAST CONFIDENCE BEGINS TO DWINDLE AS SUBTROPICAL RIDGE CONTINUES TO SHIFT TO OVER TEXAS...FORCING HEAT/MOISTURE AXIS TOWARD THE MIDWEST. NO DOUBT THERE WILL BE ADDITIONAL SHOWER/THUNDERSTORM DEVELOPMENT TODAY FROM THE CENTRAL AND NRN PLAINS INTO THE MIDWEST. QUESTION IS WHETHER ANY OF THAT CAN SNEAK INTO NRN MICHIGAN. AGAIN SHORT ANSWER IS PROBABLY NOT. ALL GUIDANCE KEEPS AXIS OF BEST MOISTURE/INSTABILITY ACROSS THE MIDWEST WHICH IS WHERE CONTINUED FOCUS FOR SHOWERS/STORMS WILL RESIDE THROUGH TONIGHT. AND IN THE ABSENCE OF ANY DECENT SYNOPTIC FORCING TO DRAG SOMETHING THIS FAR NORTH...I JUST DON/T SEE IT. HENCE HAVE REMOVED POPS FROM TONIGHTS FORECAST. && .SHORT TERM...(SUNDAY THROUGH MONDAY NIGHT) ISSUED AT 346 AM EDT SAT JUL 11 2015 HIGH IMPACT WEATHER: NONE FORECAST CHALLENGE: DETERMINING WHEN SHOWERS AND THUNDERSTORMS WILL BE MOST LIKELY. (7/12)SUNDAY...THE FORECAST WAS TOUGH TO DETERMINE AS THE TWO MODELS WERE AT ODDS WITH THE TIMING. HOWEVER, FOR THE SECOND NIGHT IN A ROW, THE ECMWF HAS MANAGED TO PLAY CATCH UP TO THE GFS IDEA. SO HAVE STARTED TO LEAN MORE TO THE GFS IDEAS WITH THE CONVECTION. LOOKING AT THE SFC BASED CAPES OVER THE REGION THE LATE MORNING AND AFTERNOON HAVE AROUND 1000J/KG ON ONE MODEL AND NEARLY 2000J/KG ON THE OTHER. COUPLED WITH THE 500MB SHORTWAVE AND THE DEVELOPING SFC WAVE, WILL PUT THE CHANCE OF THUNDERSTORMS IN THE REGION AS IT LOOKS TO BE SCATTERED. OVERNIGHT DOESN`T LOOK AT GOOD, BUT THERE IS SOME POTENTIAL AS THE INSTABILITY STILL LOOKS OKAY. THE ONE DOWNSIDE TO ALL OF THIS CONVECTION IN THE MODELS IS THAT THE DEWPOINTS OVER THE UPPER GREAT LAKES HAVE BEEN SIGNIFICANTLY LOWER THAN FORECAST IN THE RAW MODELS, SO THIS INSTABILITY MAY BE A FIGMENT OF THE MODELS IMAGINATION. (7/13)MONDAY...WILL CONTINUE TO KEEP THE POPS TO A MINIMUM AS THE DEWPOINTS ON THE MODELS ENDS UP IN THE LOWER 70S. THIS IS RARELY THE CASE IN N MICHIGAN. SO WHILE THERE MAY BE SOME THUNDER, IT IS MORE LIKELY THAT THERE WILL BE SCATTERED SHOWERS. WILL SEE HOW THIS WORKS OUT, BUT FOR NOW WILL KEEP THE FORECAST ON THE LOWER CHANCE SIDE. THIS FORECAST MAY BE A LITTLE TOO WET, BASED ON WHAT WE HAVE SEEN FOR THE YEAR SO FAR. && .LONG TERM...(TUESDAY THROUGH FRIDAY) ISSUED AT 346 AM EDT SAT JUL 11 2015 EXTENDED (TUESDAY THROUGH FRIDAY)...THERE ARE TIMING DIFFERENCES BETWEEN THE MODELS ON TUESDAY, WITH THE GFS PUSHING THE DRY AIR INTO THE UPPER GREAT LAKES SOONER THAN THE ECMWF (TUESDAY NIGHT). HOWEVER, THE BASIC IDEA IS THE SAME, WITH THE SERIES OF WAVES THAT MOVE THROUGH THE FLOW AND BRING CHANCES OF SHOWERS AND THUNDERSTORMS EVERY OTHER DAY OR TWO. TEMPERATURES LOOK TO REMAIN AROUND NORMAL FOR THIS TIME OF YEAR THROUGH THE END OF THE WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 646 AM EDT SAT JUL 11 2015 VFR CONDITIONS ARE SET TO CONTINUE TODAY AND TONIGHT WITH JUST A GRADUAL ARRIVAL AND LOWERING OF THICKER CIRRUS THROUGH THE TAF PERIOD. WILL ALSO SEE SCT-BKN CU DEVELOPMENT ACROSS NRN LOWER MICHIGAN AGAIN FOR THIS AFTERNOON...AND MAINLY IMPACTING THE APN TERMINAL SITE. WINDS...LIGHT EARLY THIS MORNING THEN TURNING MAINLY SOUTHWEST AROUND 10 KNOTS TODAY...THOUGH INFLUENCED BY LAKE BREEZE DEVELOPMENT PARTICULARLY AROUND KAPN. && .MARINE... ISSUED AT 346 AM EDT SAT JUL 11 2015 OVERALL LARGE SCALE SW-S FLOW DEVELOPS ACROSS THE WESTERN GREAT LAKES TODAY AND TONIGHT...ALTHOUGH WINDS CLOSER TO SHORE WILL BE ONCE AGAIN HEAVILY INFLUENCED BY LAKE BREEZES THIS AFTERNOON. BUT WIND SPEEDS SHOULD REMAIN 10 KNOTS OR LESS ACROSS THE REGION. A SIMILAR STORY FOR SUNDAY AND SUNDAY ALTHOUGH WINDS MAY INCREASE JUST A BIT MORE HEADING INTO SUNDAY NIGHT AS LOW PRESSURE MOVES TOWARD THE UPPER MIDWEST. BUT NO MARINE HEADLINES ARE ANTICIPATED THROUGH THE WEEKEND. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...NONE. LM...NONE. LS...NONE. && $$ UPDATE...JAZ NEAR TERM...ADAM SHORT TERM...JSL LONG TERM...JSL AVIATION...ADAM MARINE...ADAM
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
630 AM CDT SAT JUL 11 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 355 AM CDT SAT JUL 11 2015 MODELS CONTINUE TO BRING WEAK THERMAL SUPPORT FOR SHOWER AND THUNDERSTORM DEVELOPMENT EAST ACROSS THE AREA THIS MORNING. SHORT TERM MODELS SUCH AS THE HRRR AND HOP/WRF KEEP THE CONVECTION VERY SPOTTY AND THIS LOOKS REASONABLE. WILL KEEP POPS AT CHANCE FOR NOW AND ENHANCE AS DEVELOPMENT WARRANTS. THIS ACTIVITY SHOULD DECREASE TO THE EAST NORTHEAST THIS AFTERNOON AS CAPPING FROM INCREASINGLY WARM AIR SPREADS INTO THE AREA. BY LATE IN THE DAY THIS ACTIVITY...IF THERE IS ANY LEFT...SHOULD BE CONFINED TO THE FAR EASTERN PART OF THE AREA WITH SOME MINIMAL NEW DEVELOPMENT POSSIBLE. MEANWHILE...STRONG WARMING OVER THE WESTERN PART OF THE AREA MAY INCLUDE ENOUGH HEATING TO BREAK THE CAP FAR WEST LATE THIS AFTERNOON AS THE DRYLINE GETS CLOSER. THIS IDEA WAS DEEMED REASONABLE IN THE EARLIER FORECAST AND STILL LOOKS SO...BUT AGAIN ACTIVITY SHOULD BE PRETTY SPARSE. THE SURGE OF WARMING AND HEATING SHOULD TAKE TEMPERATURES UP TO THE 90S WEST...WITH INCREASINGLY HUMID 80S EAST. LOW CLOUDS WHICH WILL BE PREVALENT IN AREAS EAST THIS MORNING SHOULD HEAT OUT AND GENERALLY DECREASE LATE MORNING AND AFTERNOON. FOR TONIGHT WILL KEEP SOME CHANCE OF STORMS FAR EAST WITH THE STRONG INSTABILITY. OTHERWISE A WARM NIGHT IS IN STORE WITH LOW TEMPERATURES WITHING A COUPLE DEGREES OF 70 EVERYWHERE. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 355 AM CDT SAT JUL 11 2015 HEAT AT THE FOREFRONT OF MID RANGE CONCERNS. CAPPED ENVIRONMENT WILL BE IN PLACE WITH STRONG ELEVATED MIXED LAYER TRAPPING NEAR SURFACE MOISTURE QUITE EFFECTIVELY ACROSS MUCH OF THE AREA THROUGH THE DAY. LIKELIHOOD OF SOME CONVECTION TO OUR SOUTH AGAIN THIS EVENING WILL ACT TO MODIFY ENVIRONMENT TO SOME DEGREE...AND SOUTH TO SOUTHEAST FLOW NEAR THE SURFACE WILL REINFORCE PRESENCE OF BOUNDARY LAYER MOISTURE INTO THE AFTERNOON FROM THE JAMES VALLEY EASTWARD. EVENTUALLY...APPEARS AS IF THE SURFACE TROUGH WILL BE PUSHING INTO THE JAMES VALLEY OR A BIT EAST BY LATE SUNDAY AFTERNOON...AND OTHER THAN A BUFFER OF SLIGHTLY BETTER MIXING JUST TO THE EAST OF THIS... MIXING WILL BE QUITE CHALLENGED BY THE STRONG INVERSION. AS A RESULT...WILL PROBABLY NOT GET QUITE AS TOASTY FROM AROUND I29 EASTWARD...BUT STILL PLENTY WARM INTO THE LOWER 90S...WHILE AREAS WEST OF THE TROUGH ARE LIKELY TO FIND A FEW SPOTS REACHING THE CENTURY MARK...AS DEWPOINTS MIX GREATLY INTO THE 50S. EVEN WITH THE SLIGHTLY LOWER TEMPERATURE EXPECTATIONS...DEWPOINTS WILL SOAR WELL INTO THE 70S...AND WILL RESULT IN A LARGE AREA OF 100 TO 105 DEGREE AFTERNOON HEAT INDEX. JAMES VALLEY LOCATIONS WILL HAVE THE WORST EARLY AFTERNOON BEFORE START TO SEE MIXING LOWERING THE MOISTURE CONTENT. WITH THE LONG PERIOD SINCE LAST EXTREME HEAT AND THE NUMEROUS OUTDOOR ACTIVITIES ON THE WEEKEND...HAVE DECIDED TO ISSUE HEAT ADVISORY FROM THE JAMES VALLEY EASTWARD THROUGH THE AFTERNOON ON SUNDAY. NOT TOTALLY IMPOSSIBLE TO FIND A ROGUE HIGH BASED THUNDERSTORM TO START THE DAY...BUT SUCH A LOW CHANCE THAT HAVE KEPT CLEAR OF THE FORECAST. OTHERWISE...WAVE WILL BEGIN TO PUSH ACROSS THE MEAN UPPER RIDGE DURING SUNDAY AFTERNOON AND EVENING...AND START TO ERODE SOME OF THE WARMEST AIR ALOFT. REALLY HARD TO PICTURE THERE BEING ENOUGH LIFT TO BREAK RESIDUAL INVERSION EVEN AFTER FULL HEATING...WITH CIN LIKELY IN THE 50-150 J/KG RANGE FOR MOST LOCATIONS. OUTSIDE CHANCE THERE COULD BE A GOLDILOCKS LOCATION WHERE THE WEAKENING CAP AND FORCING ARE JUST RIGHT...BUT AT THIS POINT NOT WORTH CLUTTERING THE FORECAST WITH ISOLATED THREAT. HOWEVER...KEEP AWARE...AS THERE IS MORE THAN ENOUGH POTENTIAL INSTABILITY TO MAKE FOR A STRONGER STORM. PERHAPS A BIT BETTER CHANCE FOR THINGS TO COME TOGETHER OVER THE NORTHEASTERN CWA CLOSEST TO THE UPPER FORCING DURING THE EVENING...BUT SHOULD BE A PRETTY QUICKLY CLOSING WINDOW AS STRONGER FORCING MOVES QUICKLY PAST AND DEEPER DRYING ON WEST TO NORTHWEST FLOW SPREADS ACROSS THE AREA. NEAR SURFACE WINDS WILL DECOUPLE AND ALLOW THE SURFACE TO RECOVER QUITE A BIT IN THOSE FULLY MIXED AREAS...AND RETAIN SOME UPPER 60S DEWPOINT VALUES IN THE SOUTHEAST. ON MONDAY...AS SHOULD BE ANOTHER VERY WARM DAY...THE VERY HUMID CONDITIONS WILL BE RELAXED SOMEWHAT OVER A GOOD PORTION OF THE AREA...WITH HIGHEST READINGS EAST OF I 29 DURING THE MORNING HOURS. DEEPER MIXING SHOULD TAKE DEWPOINTS INTO THE 50S WEST TO LOWER TO MID 60S EAST DURING THE AFTERNOON...WITH WINDS AT 15 TO 25 MPH AT TIMES. THE HEAT INDEX WILL AGAIN CLIMB INTO THE 90S. WILL HAVE TO SEE IF WE GET ANOTHER INCREASE IN SMOKE BEHIND THE BOUNDARY AS IT PUSHES SOUTHWARD SUNDAY NIGHT/MONDAY...AS COULD IMPACT TEMPS A COUPLE DEGREES. THE EXTENDED RANGE FROM TUESDAY THROUGH FRIDAY WOULD SEEMINGLY BE A BIT MORE ACTIVE IN GENERAL...WITH RIDGE ACROSS THE NORTHERN PLAINS...BREACHED PERIODICALLY WITH SYSTEMS COMING OUT OF THE WEST TO SOUTHWEST FLOW ALOFT. A COMMON FEATURE IN MODELS IS WAVE AROUND WEDNESDAY...AND HAVE MAINTAINED HIGHER PRECIP CHANCES WITH THIS FEATURE. TEMPS SHOULD REMAIN FROM NORMAL TO SLIGHTLY ABOVE NORMAL... BUT WILL HAVE TO WATCH TO SEE IF SLIGHTLY MORE AMPLIFIED SOLUTION IN ECMWF COULD KEEP A BETTER BACKDOOR BOUNDARY AROUND MIDWEEK. ANOTHER WAVE HAS PROXIMITY TO THE END OF THE FORECAST CYCLE...BUT DRASTICALLY DIFFERING TIMING IN GREATER ENSEMBLE OF SOLUTIONS FOR SURFACE REFLECTION. WATCHING FOR ANOTHER EASTWARD SURGE IN WARMER AIR AHEAD OF THIS WAVE...WHICH COULD BE ON THE WAY FOR LATE WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 624 AM CDT SAT JUL 11 2015 UNTIL 11/16Z FREQUENT CEILINGS 1-3K FT AND VISIBILITIES 3-5SM/BR WITH LOCAL CEILINGS BELOW 1K FEET. AFTER 12/16Z VFR. ISOLATED SHRA/TSRA UNTIL 12/03Z. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR SDZ038>040- 053>056-059>062-065>071. MN...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR MNZ071-072-080- 081-089-090-097-098. IA...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR IAZ001>003- 012>014-020>022-031-032. NE...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR NEZ013-014. && $$ SHORT TERM... LONG TERM...CHAPMAN AVIATION...
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
622 AM CDT SAT JUL 11 2015 .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 339 AM CDT SAT JUL 11 2015 REGIONAL RADARS THIS MORNING SHOWING SOME CONVECTION THIS MORNING OVER NORTHERN MISSOURI WITH ANOTHER AREA OF CONVECTION OVER EASTERN NEBRASKA. THIS ACTIVITY IS NORTH OF A WARM FRONT THAT EXTENDS ACROSS NORTHERN KANSAS AND MISSOURI AND AHEAD OF A WEAK TROUGH OF LOW PRESSURE FROM KANSAS INTO NORTH DAKOTA. WATER VAPOR SATELLITE SHOWS ONE SHORT WAVE TROUGH OVER NEBRASKA AND KANSAS WITH ANOTHER OVER NORTH DAKOTA. THE TREND IN THE 11.00Z MODELS AND 11.03Z RAP IS FOR THE WAVE OVER NEBRASKA AND KANSAS TO FLATTEN OUT AS IT MOVES NORTHEAST INTO THE TOP PART OF THE RIDGE AXIS OVER THE CENTRAL PART OF THE COUNTRY. THE WAVE OVER NORTH DAKOTA WILL ALSO CONTINUE TO MOVE NORTHEAST INTO SOUTHERN CANADA THROUGH THE DAY. THE SURFACE WARM FRONT SHOULD LIFT SLOWLY TO THE NORTH WITH A GENERAL MODEL CONSENSUS OF IT REACHING ABOUT THE IOWA/MISSOURI BORDER. THIS WILL KEEP THE BEST MOISTURE TRANSPORT WELL SOUTH OF THE AREA TODAY AND SHOULD KEEP MOST OF THE RAIN TO THE SOUTH AS WELL. THE MESO MODELS SEEMED TO HAVE LATCHED ON TO THIS AS WELL WITH THE 11.00Z CR-NAM NEST...HI-RES ARW AND NMM KEEPING THE AREA DRY WHILE THE 11.00Z NAM12 AND 11.05Z HRRR STILL TRY TO BRING THE REMAINS OF SOME DEVELOPING CENTRAL IOWA CONVECTION INTO THE SOUTHERN SECTIONS FOR THIS MORNING. BASED ON ALL THESE SOLUTIONS...HAVE TRENDED THE RAIN CHANCES DOWN FOR TODAY WITH ABOUT A 20 PERCENT CHANCE ACROSS THE NORTH TO AT MOST A 40 PERCENT CHANCE IN THE SOUTH. THESE COULD STILL BE TOO HIGH AS IT COULD END UP BEING TOTALLY DRY NORTH OF THE IOWA/MINNESOTA BORDER. UPPER LEVEL HEIGHTS SHOULD BUILD A LITTLE BIT OVER THE REGION TONIGHT AS THE SHORT WAVE TROUGHS MOVE OFF TO THE EAST. THE WARM FRONT WILL CONTINUE TO LIFT SLOWLY NORTH TAKING ON A MORE NORTHWEST TO SOUTHEAST ORIENTATION FROM A DEVELOPING AREA OF LOW PRESSURE OVER NORTH DAKOTA INTO CENTRAL ILLINOIS. THE NAM REALLY RAMPS UP THE MOISTURE TRANSPORT INTO THIS BOUNDARY AROUND 06Z SUNDAY AND BREAKS OUT CONVECTION NORTH OF THE BOUNDARY AND ACROSS THE AREA. THE 11.00Z GFS SOMEWHAT HINTS AT THIS AS WELL WHILE THE 11.00Z ECMWF KEEPS THE BOUNDARY FARTHER SOUTH AND MOST OF THE RAIN TO THE SOUTH AS WELL. THE HI-RES NMM IS SIMILAR TO THE NAM WHILE THE HI-RES ARW IS COMPLETELY DRY FOR TONIGHT. CONCERNED THAT THE NAM IS TOO STRONG WITH THE MOISTURE TRANSPORT TONIGHT AND WILL ONLY CARRY A GENERAL 30 TO 40 PERCENT CHANCE ACROSS THE AREA. THE REAL ACTION AND BEST CHANCES FOR RAIN MAY COME SUNDAY NIGHT. A SHORT WAVE TROUGH IS EXPECTED TO COME OUT OF THE WEAKENING UPPER LEVEL LOW CURRENTLY OVER OREGON AND NEVADA. THIS WAVE SHOULD TOP THE UPPER LEVEL RIDGE AND THEN SLIDE SOUTHEAST ACROSS THE AREA SUNDAY NIGHT. THE GFS SUGGESTS THIS WAVE WILL PRODUCE SOME MODERATE PV ADVECTION IN THE 500-300 MB LAYER AS IT COMES ACROSS. THIS LIFT SHOULD BE AIDED BY SOME JET DYNAMICS FROM THE LEFT EXIT REGION OF THE 300 MB JET AS THIS COMES IN WITH THE SHORT WAVE TROUGH. THE WARM FRONT SHOULD CONTINUE TO EDGE NORTH EXTENDING FROM EASTERN NORTH DAKOTA INTO ILLINOIS WITH THE GFS SHOWING WEAK TO MODERATE FRONTOGENESIS IN THE 1000-850 MB LAYER NORTH OF THE FRONT. AS THE SHORT WAVE TROUGH APPROACHES...A CONVECTIVE COMPLEX SHOULD FROM LATE SUNDAY AFTERNOON OVER THE EASTERN DAKOTAS AND THEN SLIDE SOUTHEAST THROUGH THE NIGHT ALONG AND NORTH OF THE WARM FRONT. THERE SHOULD STILL BE AMPLE CAPE AVAILABLE FOR THE STORMS TO WORK WITH AS THEY MOVE INTO THE AREA. THE GFS SUGGESTS UP TO 2500 J/KG OF ML CAPE SUNDAY EVENING ONLY DROPPING OFF TO 1500 J/KG DURING THE OVERNIGHT HOURS. UP TO 40 KNOTS OF SHEAR SHOULD MOVE IN AHEAD OF THE SHORT WAVE TROUGH WITH THIS BEING PRIMARILY IN THE 0-3 KM LAYER. THIS WILL PRESENT THE OPPORTUNITY FOR A NOCTURNAL MCS TO ROLL ACROSS THE AREA WITH A SEVERE WIND THREAT. HAIL DOES NOT LOOK TO BE MUCH OF THREAT WITH WARM CLOUD DEPTHS ON THE ORDER OF 3.5 TO 4 KM...BUT THERE SHOULD BE SOME GOOD RAINFALL RATES AND LOCALLY HEAVY RAINS. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 339 AM CDT SAT JUL 11 2015 THE UPPER LEVEL RIDGE SHOULD BRIEFLY BUILD BACK OVER THE REGION EARLY IN THE WEEK BEFORE FLATTENING OUT WITH ZONAL FLOW OVER THE UPPER MIDWEST. THIS PATTERN LOOKS TO BE A DIRTY FLOW WITH THE POTENTIAL FOR SEVERAL SHORT WAVE TROUGHS TO BE EMBEDDED IN THE FLOW AND COME ACROSS THE REGION. DECENT AGREEMENT IN TIMING OF A WAVE FOR WEDNESDAY BETWEEN THE ECMWF AND GFS...BUT DIFFERENCES IN STRENGTH WITH THE GFS BEING STRONGER. AFTER THAT...CONSIDERABLE DIFFERENCES IN HOW AN UPPER LEVEL LOW COMING ACROSS SOUTHWEST CANADA IS HANDLED. THE GFS OPENS THIS SYSTEM UP AND BRINGS IT TOWARD THE AREA BY THE END OF THE WEEK WHILE THE ECMWF KEEPS IT AS A CLOSED LOW HOLDING IT BACK WITH RIDGING OVER THE REGION. WITH ALL THE UNCERTAINTY...WILL STAY WITH GENERAL 20 TO 40 PERCENT CHANCES THROUGH THE PERIOD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 622 AM CDT SAT JUL 11 2015 A GENERALLY VFR PERIOD EXPECTED TODAY/TONIGHT. INCREASING MOISTURE DOES LOOK TO SPREAD 3500-4500 FT BKN CIGS ACROSS THE AREA LATE THIS MORNING INTO EARLY THIS EVENING...WITH THESE CLOUDS/MOISTURE SPREADING NORTHWARD ACROSS IA EARLY THIS MORNING. SOME DRYING OF THE LOWER PORTION OF THE COLUMN TONIGHT...WITH MORE SCT CUMULUS/STRATO- CUMULUS EXPECTED AFTER 01-02Z. SHRA/TSRA CHANCES AT THE TAF SITES MORE IN QUESTION THIS AFTERNOON THRU TONIGHT. GIVEN EXPECTED WIDELY SCT TO SCT COVERAGE OF ANY SHRA/TSRA THIS AFTERNOON/TONIGHT...AND LOWER CONFIDENCE IN THE TIMING OF ANY PERIODS WHEN SHRA/TSRA WOULD BE MORE LIKELY TO OCCUR...CONTINUED THE TREND OF LEAVING VCSH/VCTS OUT OF THE TAFS FOR NOW. IF DETAILS BECOME CLEARER ON SHRA/TSRA OCCURRENCE NEAR/AT KLSE/KRST LATER CYCLES MAY BE ABLE TO MENTION OF SUCH TO THE TAFS AS NEEDED. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...04 LONG TERM....04 AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
143 PM MST SAT JUL 11 2015 .UPDATE...AVIATION AND FIRE WEATHER DISCUSSIONS... && .SYNOPSIS...LITTLE CHANGE IN THE WEATHER PATTERN IS FORECAST THE NEXT SEVERAL DAYS. DRY WEATHER WITH NEAR NORMAL TEMPERATURES ARE EXPECTED IN SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA...WITH A THREAT OF AFTERNOON AND EVENING MOUNTAIN THUNDERSTORMS IN EASTERN ARIZONA...GENERALLY EAST OF PHOENIX. && .DISCUSSION.../ISSUED AT 840 AM MST 11 JULY/... TODAY AND TONIGHT...SOME BIG CHANGES HAVE OCCURRED IN THE PAST 24 HOURS WITH REGARDS TO THE DISTRIBUTION OF MONSOON MOISTURE. FOR THE PAST 2 DAYS MOST OF THE MOISTURE WAS CONTAINED IN SOUTHEAST AZ WITH THE DRY LINE WAVERING BETWEEN PHOENIX AND TUCSON. THIS MORNINGS PHOENIX SOUNDING NOW SHOWS THE CENTRAL DESERTS IN THE MONSOON SOUP...SO TO SPEAK. FOR EXAMPLE...THE 12Z FRIDAY PHOENIX SOUNDING SHOWED A PRECIP WATER (PW) VALUE OF 0.69 INCHES AND AN 800 MB DEWPOINT OF 0 DEGREES C. IN CONTRAST...ITS NOW 1.35 INCHES OF PW WITH AN 800 MB DEWPOINT OF 13 DEG C. MONSOON MOISTURE WILL CONTINUE TO SPREAD SLOWLY WEST AND NORTH THIS WEEKEND...COVERING THE ENTIRE STATE BY MONDAY. ADDITIONALLY...BOTH PHOENIX AND TUCSON SOUNDINGS SHOWED CONSIDERABLE ML C.A.P.E.(500-1000 J/KG)...WITH LOW CONVECTIVE TRIGGER TEMPS (GLOBE 78 DEG F... TUCSON 89 F...AND HILLTOP AT 5700 FEET 70 F)...AND SIGNIFICANT VERTICAL SHEAR PROFILES...BETTER IN SOUTHEAST AZ. AT THE SAME TIME HOWEVER...SATELLITE IMAGERY SHOWED A WEAK DISTURBANCE MOVING OUT OF NORTHEAST AZ FOLLOWED BY A SIGNIFICANT UPPER LEVEL ANTI-CYCLONIC CIRCULATION FEATURE CONNECTED TO THE SUBTROPICAL JET OFFSHORE NORTHERN BAJA. STRONG ANTI-CYCLONIC CIRCULATION TENDS TO STABILIZE THE ATMOSPHERE A BIT...BUT WORKING AGAINST STRONG AFTERNOON THERMODYNAMICS TODAY WITH A EARLY START TO MOUNTAIN CONVECTION. EVEN THOUGH THE POTENTIAL ENERGY HAS INCREASED OVER THE LOWER DESERTS BETWEEN PHOENIX AND CASA GRANDE...WE STILL THINK STORMS WILL BE RELEGATED TO THE HIGHER TERRAIN NORTHEAST THROUGH SOUTHEAST OF PHOENIX. PERHAPS EARLY EVENING CONVECTIVE OUTFLOWS ON THE LOWER DESERTS ARE POSSIBLE. ALSO BECAUSE OF THE MODERATE VERTICAL WIND SHEAR PROFILES...SOME CONVECTION IN SOUTHERN GILA COUNTY ZONE 24 MAY BECOME ORGANIZED WITH HAIL AND STRONG GUSTY SURFACE WINDS. OTHERWISE CURRENT FORECASTS LOOK OK. NO UPDATES PLANNED TODAY. .PREVIOUS DISCUSSION...511 AM MST... UNSEASONABLY STRONG UPPER LOW OVER NRN CA/WRN NV CONTINUED TO WEAKEN AND LIFT NEWD EARLY THIS MORNING...MEANWHILE THE SWLY FLOW AHEAD OF IT REMAINED STRONG ENOUGH OVER THE DESERT SOUTHWEST TO CONFINE MOISTURE AND CONVECTION TO FAR ERN AND SERN AZ...MAINLY AREAS EAST OF PHOENIX. IR IMAGERY AT 2 AM SHOWED CLEAR SKIES WEST OF PHOENIX WITH PARTLY CLOUDY SKIES PRESENT FROM PHOENIX EAST. A COUPLE OF INTERESTING THINGS TO NOTE...DESPITE THE CONTINUED PRESENCE OF RELATIVELY DRY SOUTHWEST FLOW ALOFT OVER THE AREA AS SEEN IN THE LATEST 00Z PLOT DATA...MOISTURE DID INCREASE IN THE PHOENIX AREA DURING THE DAY YESTERDAY AND THE PHOENIX RAOB SHOWED PWAT UP TO 1.35 INCHES...WHICH WAS HIGHER THAN TUCSON WHICH REPORTED 1.21 INCHES. ALSO...FRI EVENING SURFACE DEWPOINTS OVER THE CENTRAL DESERTS HAD CLIMBED INTO THE LOW TO MID 50S...A RISE OF MORE THAN 20 DEGREES OVER THE PAST 24 HOURS. SO...DESPITE THE SOUTHWEST FLOW ALOFT WITH A VERY LAMINAR UPPER STREAMLINE FIELD AND NO SIGNIFICANT DISTURBANCES MOVING THROUGH THE FLOW...AROUND MIDNIGHT ISOLATED SHOWERS/STORMS STARTED TO DEVELOP OVER THE NORTH VALLEY...NEAR NEW RIVER...AND THEY MOVED QUICKLY TO THE NORTH/NORTHEAST. LATEST HRRR SUGGESTS THESE STORMS WILL WEAKEN AND MOVE OUT OF THE AREA WITHIN THE NEXT 1-2 HOURS LEAVING PARTLY CLOUDY OR MOSTLY CLEAR SKIES BEHIND FOR THE REST OF TONIGHT. FOR THE WEEKEND GUIDANCE REMAINS CONSISTENT THAT THE GRADUALLY WEAKENING TROFFING TO OUR NORTHWEST WILL ALLOW THE MAIN UPPER HIGH TO BUILD BACK WESTWARD...ALLOWING HEIGHTS TO RISE AND TEMPS TO CLIMB BACK TOWARDS NORMAL READINGS. STILL...THE MAIN HIGH CENTER REMAINS SUPPRESSED WELL TO THE EAST/SOUTHEAST OF ARIZONA AND AS SUCH STEERING FLOW REMAINS SOUTH/SOUTHWESTERLY. AS SUCH WE ARE STILL EXPECTED CONVECTION TO BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX...MAINLY AREAS OF SOUTHERN GILA COUNTY AS WELL AS EASTERN PORTIONS OF ZONE 28 ACROSS NORTHWEST PINAL COUNTY. ALL AREAS WEST OF MARICOPA COUNTY SHOULD STAY GENLY CLEAR WITH POPS LOW SINGLE DIGITS OR ZERO. AS FOR THE UPCOMING WORK WEEK...MONDAY THROUGH FRIDAY...GUIDANCE INCLUDING THE GFS AND ECMWF CONTINUE TO SUGGEST THAT TROFFING TO OUR NORTHWEST...OVER THE NORTHWESTERN STATES...WILL REMAIN STRONG ENOUGH TO KEEP THE MAIN UPPER HIGH SUPPRESSED TO OUR EAST AND SOUTHEAST. THIS WILL RESULT IN A CONTINUED SOUTHWESTERLY FLOW ACROSS MOST OF OUR AREA THROUGH THE PERIOD. MOISTURE/INSTABILITY/CAPE WILL BE MINIMAL FROM PHOENIX WESTWARD EACH DAY AND CONVECTION WILL REMAIN CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST AND SOUTHEAST OF PHOENIX. WE ARE LOOKING AT A VERY LOW GRADE MONSOON FOR THE DURATION OF THE FORECAST PERIOD. HIGH TEMPERATURES WILL CLIMB SLIGHTLY ABOVE NORMAL EACH DAY WITH HOTTER DESERTS REACHING NEAR 110 DEGREES. DESPITE H5 HEIGHTS STAYING MOSTLY AT OR BELOW 591DM EACH DAY...THE DRIER AIR AND SUNNY AFTERNOONS WILL ALLOW TEMPS TO RISE A BIT ABOVE SEASONAL NORMALS EACH DAY. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... ANOTHER AFTERNOON WITH BREEZY SOUTH-SOUTHWESTERLY WINDS FOR THE PHOENIX AREA AIR FIELDS. EXPECTING A WESTERLY DIRECTION THROUGH EARLY EVENING BUT WIND GUSTS SHOULD BE AT OR BELOW 20 KT. INCREASED MID AND HIGH CLOUDS WILL PERSIST THROUGH THE AFTERNOON AND EVENING HOURS...WITH EXPECTED THUNDERSTORMS TO THE EAST OF PHOENIX. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... TUESDAY THROUGH SATURDAY... THE UPPER LEVEL FLOW PATTERN WILL SHIFT SLIGHTLY AS THE SUB-TROPICAL HIGH SHIFTS WESTWARD AND REESTABLISHES ITSELF JUST TO THE EAST OF THE DESERT SOUTHWEST NEXT WEEK. THIS WILL LEAD TO WARMING TEMPERATURES AND LIKELY SOME MOISTURE RETURN INTO EASTERN AND POSSIBLY CENTRAL ARIZONA. THUNDERSTORM CHANCES WILL BE LIMITED TO HIGHER TERRAIN LOCATIONS NORTH AND EAST OF PHOENIX. AFTERNOON MINIMUM HUMIDITY LEVELS IN A 10-15 PERCENT RANGE WILL BE PRESENT ACROSS THE LOWER DESERTS THROUGHOUT THE WEEK. WINDS WILL BE BREEZY AND MOSTLY OUT OF THE SOUTHWEST EACH AFTERNOON WITH GUSTS UP TO 20 MPH. && .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...VASQUEZ/CB AVIATION...DEWEY FIRE WEATHER...DEWEY
AREA FORECAST DISCUSSION
NWS RENO NV
230 PM PDT SAT JUL 11 2015 .SYNOPSIS... DRIER SOUTHWEST FLOW ALOFT THIS WEEKEND WILL BRING DECREASING THUNDERSTORM COVERAGE AND SLOWLY WARMING TEMPERATURES. DRY WEATHER IS EXPECTED NEXT WEEK WITH TEMPERATURES WARMING TO AROUND AVERAGE BY TUESDAY OR WEDNESDAY. && .SHORT TERM... NO MAJOR MODIFICATIONS WERE MADE TO THE PREVIOUS FORECAST. THE ONLY MINOR CHANGES WERE TO EXTEND THE AREA OF SLIGHT CHANCES OF THUNDERSTORMS DOWN TO THE SIERRA CREST OF MONO COUNTY FOR THIS EVENING. THE HRRR AND NAM ARE FAVORING SOME CHANCES OF A THUNDERSTORM AND CUMULUS DEVELOPMENT ON VISIBLE IMAGERY SUPPORTS AT LEAST A 15% COVERAGE. OTHERWISE, ONLY LOOKING AT SLIGHT CHANCES OF A THUNDERSTORM AGAIN SUNDAY AFTERNOON FROM EASTERN MONO COUNTY NORTHEAST THROUGH EASTERN PERSHING COUNTY. THEN, DRIER SOUTHWESTERLY FLOW DEVELOPS MONDAY ONWARD. NAM SEEMS TO BE OVER-CONVECTING MONDAY AFTERNOON IN MONO COUNTY, BUT MAY SEE A STRAY SHOWER/THUNDERSTORM; KEPT CHANCES AROUND 10%. THE THERMAL AND PRESSURE GRADIENTS WILL ONLY BE ABLE TO SUPPORT AFTERNOON GUSTS FROM 20 TO 25 MPH EACH AFTERNOON WITH THE MORE TYPICAL AFTERNOON ZEPHYR PATTERN. TEMPERATURES WILL WARM BACK INTO THE MID/UPPER 80S FOR WESTERN NEVADA BY MONDAY WITH MID/UPPER 70S IN THE SIERRA. BOYD .LONG TERM...TUESDAY THROUGH SATURDAY... FEW CHANGES IN THE EXTENDED FORECAST WITH A DRY AND MORE STABLE PATTERN IN STORE FOR NEXT WEEK. HIGH TEMPERATURES WILL REMAIN NEAR AVERAGE VALUES FOR THIS TIME OF YEAR WITH UPPER 80S TO LOWER 90S ACROSS WESTERN NEVADA TO START THE WEEK WITH GRADUAL WARMING INTO THE WEEKEND. UPPER 70S TO LOW 80S CAN BE EXPECTED OVER THE SIERRA VALLEYS NEXT WEEK. INSTABILITY WILL DEVELOP ACROSS THE SIERRA MAINLY THROUGH ALPINE AND MONO COUNTIES EACH DAY WITH MAINLY CUMULUS DEVELOPMENT IN THESE AREAS TUESDAY THROUGH THURSDAY. THE LIMITING FACTOR LOOKS TO BE ENOUGH DEEP LAYER MOISTURE FOR STORM DEVELOPMENT. AT THIS POINT WILL KEEP CHANCES BELOW 15% FOR THESE AREAS. INSTABILITY AND MOISTURE LOOKS MORE FAVORABLE HEADING INTO THE WEEKEND BUT WILL KEEP MENTION OF STORMS OUT OF THE FORECAST FOR NOW AS UNCERTAINTY STILL IS SIZABLE IN TERMS OF RESOLVING THE UPPER LEVEL PATTERN. BOTH THE GFS AND EC ATTEMPT A CUT-OFF LOW OFF THE SOUTHERN CALIFORNIA COAST WHICH LEAVES THE SIERRA IN MORE OF A TROUGH PATTERN TOWARDS THE WEEKEND IN THE GFS WHILE THE EC DEVELOPS A SHORTWAVE RIDGE. THIS IS ALMOST THE REVERSE OF WHAT EACH MODEL HAS BEEN SHOWING IN THEIR RESPECTIVE LAST FEW CYCLES. NEEDLESS TO SAY, ENSEMBLES SPREADS ARE LARGE WILL MAINTAIN PERSISTENCE WITH THE CURRENT FORECAST. FUENTES && .AVIATION... ISOLATED STORMS ARE POSSIBLE THROUGH 03Z MAINLY FOR AREAS IN WEST CENTRAL NEVADA EAST OF KNFL, BUT OVERALL AVIATION-RELATED IMPACTS WILL BE REDUCED COMPARED TO RECENT DAYS. FOR SUNDAY, ISOLATED STORMS ARE POSSIBLE NORTH OF A FALLON-SUSANVILLE LINE BUT THE MAIN TERMINALS SHOULD REMAIN FREE OF CONVECTION. SW-W WINDS WITH GUSTS 20- 25 KT ARE PROBABLE, MAINLY BTWN 21Z-04Z. TF && .REV WATCHES/WARNINGS/ADVISORIES... NV...NONE. CA...NONE. && $$ FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
200 PM PDT SAT JUL 11 2015 .SYNOPSIS... RESIDUAL SHOWERS AND THUNDERSTORMS OVER THE SIERRA CREST WILL CONTINUE THROUGH TODAY. ELSEWHERE BELOW NORMAL TEMPERATURES AND DRY CONDITIONS REMAIN DUE TO A SOUTHWEST FLOW ALOFT OVER THE REGION. WARMING AND DRYING TRENDS WILL CONTINUE ACROSS THE AREA OVER THE NEXT WEEK. && .DISCUSSION... AS THE HIGH-RESOLUTION MODELS HAD FORECAST...MIDDAY SATELLITE LOOPS SHOW CUMULUS CLOUDS DEVELOPING NOT ONLY ALONG THE SOUTHERN SIERRA NEVADA BUT ALSO OVER THE DIABLO RANGE NEAR THE JUNCTION OF SAN BENITO...MONTEREY AND FRESNO COUNTIES AND OVER /AND SOUTH OF/ THE SAN EMIGDIO MOUNTAINS NEAR FRAZIER PARK. AS OF 20Z /1300 PDT/ NO LIGHTNING HAD BEEN DETECTED IN THE WFO HANFORD WARNING/FORECAST AREA BUT THE HRRR SUGGESTED THAT CONVECTION MIGHT NOT BEGIN BEFORE 22Z /1500 PDT/. THE MODELS ARE IN GENERAL AGREEMENT WITH AN UPPER-LEVEL TROUGH OVER CALIFORNIA THROUGH THE MIDDLE OF NEXT WEEK WITH A SERIES OF SHORT- WAVES MOVING THROUGH THE TROUGH. THIS WILL KEEP A SOUTHWEST FLOW ALOFT OVER CENTRAL CALIFORNIA FOR DRY WEATHER AND CONTINUED BELOW NORMAL TEMPERATURES THE NEXT FEW DAYS. FOR THE LATTER HALF OF NEXT WEEK...THE MEDIUM-RANGE MODELS BUILD AN UPPER-LEVEL RIDGE OVER THE SOUTHERN U.S. WESTWARD...LIFTING THE TROUGH NORTHWARD AND WARMING TEMPERATURES ABOVE NORMAL BY THURSDAY WHEN CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY HIGHS ARE FORECAST TO BE AROUND 100. HOWEVER...THE GFS AND ECMWF DIFFER CONCERNING AN UPPER-LEVEL TROUGH THAT IS FORECAST TO MOVE THROUGH THE PACIFIC NORTHWEST TOWARD THE END OF NEXT WEEK...AND THE FORECAST HAS LITTLE CHANGE IN TEMPERATURES FOR FRIDAY AND SATURDAY DUE TO THE MODEL DIFFERENCES. THE BIGGEST UNCERTAINTY CONCERNS TROPICAL DEPRESSION 5-E OFF THE SOUTHWESTERN COAST OF MEXICO. THE MODELS SLOWLY LIFT THE SYSTEM... WHICH WOULD BE NAMED DOLORES IF IT REACHES TROPICAL STORM STRENGTH... NORTHWEST WITH THE ECMWF HAVING A MORE WESTERLY TRACK THAN THE GFS. BY SATURDAY NIGHT...THE GFS HAS THE SYSTEM WEST OF THE TIP OF BAJA CALIFORNIA WITH A SOUTHERLY FLOW OVER CALIFORNIA. IF THE GFS IS CORRECT...AND THE EXTENDED GFS COULD EASILY CHANGE OVER THE NEXT SEVERAL DAYS...COULD SEE TROPICAL MOISTURE MOVING INTO INTERIOR CENTRAL CALIFORNIA FROM THE SOUTH. AT THIS POINT THERE IS LOW CONFIDENCE IN THIS SOLUTION DUE TO THE DIFFERENCES BETWEEN THE GFS AND THE ECMWF AND HAVE OPTED TO KEEP POPS MAINLY IN SINGLE DIGITS NEXT SATURDAY. && .AVIATION... OTHER THAN AN ISOLATED THUNDERSTORM OR TWO ALONG THE COASTAL RANGES WEST OF INTERSTATE 5 AND IN THE VICINITY OF FRAZIER PARK EARLY THIS EVENING...ISOLATED THUNDERSTORMS WITH LOCAL MVFR CEILINGS CAN BE EXPECTED ALONG THE SIERRA CREST UNTIL 06Z SUNDAY. OTHERWISE...VFR CONDITIONS WILL PREVAIL THROUGHOUT THE CENTRAL CA INTERIOR DURING THE NEXT 24 HOURS. && .AIR QUALITY ISSUES... NONE. && .CERTAINTY... THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH. THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS HIGH. THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD. CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL INFORMATION AND/OR TO PROVIDE FEEDBACK. && .CLIMATE... RECORDS SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR KFAT 07-11 110:1961 82:1888 78:2002 52:1974 KFAT 07-12 109:2012 82:1995 81:1999 54:1965 KFAT 07-13 110:1983 84:1932 83:1999 55:1903 KBFL 07-11 110:1961 83:1936 79:2002 51:1906 KBFL 07-12 113:1913 81:1995 80:1999 48:1914 KBFL 07-13 111:1908 87:1995 85:1999 46:1914 && .HNX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ PUBLIC...SANGER AVN/FW...DURFEE SYNOPSIS...ANDERSEN WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION...UPDATED
NWS SAN JOAQUIN VALLEY - HANFORD CA
958 AM PDT SAT JUL 11 2015 .UPDATE... ADDED SLIGHT CHANCE OF THUNDERSTORMS TO THE SAN EMIGDIO MOUNTAINSAND TO THE DIABLO RANGE NEAR COALINGA THIS AFTERNOON AND EVENING. .SYNOPSIS... A LOW PRESSURE SYSTEM CONTINUES TO MOVE OUT OF THE REGION WITH RESIDUAL SHOWERS AND THUNDERSTORMS IN THE HIGH COUNTRY OF THE SIERRA WILL CONTINUE. BY SATURDAY...A DRY SOUTHWEST FLOW WILL THEN PREVAIL BRINGING A WARMING TREND AND DRY CONDITIONS TO THE REGION. && .DISCUSSION... THIS MORNING/S HIGH-RESOLUTION MODELS...ARW/WRF-NMM/HRRR AND NAM-12...ALL IN AGREEMENT WITH POSSIBLE CONVECTION OVER THE SAN EMIGDIO MOUNTAINS NEAR FRAZIER PARK...AND OVER THE DIABLO RANGE WEST OF COALINGA...THIS AFTERNOON AND EARLY EVENING. HRRR RADAR FORECAST INDICATES BEST CHANCES FOR ISOLATED THUNDERSTORMS BETWEEN 22Z /1500 PDT/ THIS AFTERNOON AND 02Z SUNDAY /1900 PDT THIS EVENING/. HAVE UPDATED THE FORECAST TO ADD SLIGHT CHANCE POPS FOR THESE AREAS THIS AFTERNOON AND EVENING. OTHERWISE...NO CHANGES TO THE FORECAST. && .PREV DISCUSSION... /ISSUED 232 AM PDT SAT JUL 11 2015/ DISCUSSION...STILL A FEW SHOWERS AND THUNDERSTORMS BROKE OUT ON FRIDAY AFTERNOON NEAR THE SIERRA CREST AND WITH THE WEAKENING LOW PRESSURE SYSTEM LINGERING OVER THE REGION, THE THREAT OF CONVECTION WILL CONTINUE FOR ANOTHER DAY OVER THE MOUNTAINS. COOLER THAN NORMAL WEATHER WILL ALSO PREVAIL AS HEIGHTS REMAIN RELATIVELY LOW FOR MID JULY. FOR THE NEXT FEW DAYS, LITTLE OVERALL CHANGE IN THE PATTERN WILL OCCUR WITH THE REMAINING MOISTURE OVER THE SIERRA GETTING PUSHED TO THE EAST WHILE A DRIER SOUTHWEST FLOW CONTINUES. MODELS ARE IN GOOD AGREEMENT AT LEAST THROUGH MID WEEK OF KEEPING A WEAK TROUGH PATTERN OVER CALIFORNIA AND THIS ALLOW FOR A SLOW RETURN TO TEMPERATURES CLOSER TO NORMAL FOR JULY. BY LATER IN THE WEEK MODELS BEGIN TO TREND TOWARDS A SOLUTION OF A RIDGE OVER DESERT SOUTHWEST AND EAST PACIFIC AND TRANSITORY TROUGHS WORKING EAST ALONG THE CANADIAN BORDER. THIS PATTERN WILL NOT ALLOW THE MONSOON TO KICK BACK IN, THUS THE FORECAST REMAINS DRY. && .AVIATION... LCL MVFR IN SHOWERS/THUNDERSTORMS OVER SIERRA NEVADA CREST BETWEEN 20Z AND 06Z SATURDAY. OTHERWISE...VFR CONDITIONS WILL PREVAIL THROUGHOUT THE CENTRAL CA INTERIOR DURING THE NEXT 24 HOURS. && .AIR QUALITY ISSUES... NONE. && .CERTAINTY... THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH. THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS HIGH. THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD. CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL INFORMATION AND/OR TO PROVIDE FEEDBACK. && .CLIMATE... RECORDS SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR KFAT 07-11 110:1961 82:1888 78:2002 52:1974 KFAT 07-12 109:2012 82:1995 81:1999 54:1965 KFAT 07-13 110:1983 84:1932 83:1999 55:1903 KBFL 07-11 110:1961 83:1936 79:2002 51:1906 KBFL 07-12 113:1913 81:1995 80:1999 48:1914 KBFL 07-13 111:1908 87:1995 85:1999 46:1914 && .HNX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ PUBLIC...SANGER AVN/FW...MOLINA PREV DISCUSSION...DUDLEY SYNOPSIS...DUDLEY WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS PUEBLO CO
248 PM MDT SAT JUL 11 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 247 PM MDT SAT JUL 11 2015 AN UPR HIGH CENTER IS OVR ERN TX TODAY AND IS EXPECTED TO SHIFT WESTWARD OVR TX TONIGHT AND SUNDAY. THERE IS LIMITED MSTR OVR THE AREA TODAY...BUT STILL ENOUGH FOR ISOLD SHOWERS/TSTMS MAINLY OVR AND NR THE HYR TRRN. THE NAM KEEPS PCPN TIED TO THE HIGHER TRRN... INCLUDING THE PALMER DVD...WHILE THE LATEST RUN OF THE HRRR IS SHOWING THE POTENTIAL FOR A FEW STORMS TO MOVE OUT OVR THE I-25 CORRIDOR AND OVR BACA AND ERN LAS ANIMAS COUNTIES EARLY THIS EVENING. SHOULD SEE MOST IF NOT ALL CONVECTION END BEFORE MIDNIGHT. ON SUNDAY THE MSTR WL STILL BE LIMITED AND HIGH TEMPS SHOULD GENERALLY BE A LITTLE ABOVE AVERAGE. THERE SHOULD AGAIN BE SOME ISOLD SHOWERS AND TSTMS...MOSTLY OVR AND NR THE MTN AREAS. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 247 PM MDT SAT JUL 11 2015 GENERAL WEATHER PATTERN THROUGH THE EXTENDED PERIOD FAVORS NEAR NORMAL TEMPERATURES AND BELOW NORMAL RAINFALL. SUNDAY NIGHT...UPPER RIDGE CENTERED ACROSS THE SOUTHERN PLAINS. ANY DIURNAL CONVECTION IS FORECAST TO WANE THROUGH THE EVENING HOURS. MONDAY...DURING THE DAY THE NORTHWEST US TROUGH IS FORECAST TO EDGE EAST...AND MOISTURE ALONG THE PERIPHERY OF THE UPPER RIDGE WILL BE IN WESTERN AND CENTRAL COLORADO DURING THE AFTERNOON AND EVENING. WE HAVE LOW END SCATTERED TO ISOLATED POPS GOING AND THAT SEEMS REASONABLE. WITH SOME MORE CLOUDS AND SHOWERS...HIGH TEMPERATURES WILL BE A BIT LOWER ACROSS THE CWA...BUT IT WILL STILL BE QUITE WARM...WITH SEASONAL HIGHS IN THE UPPER 80S TO 90S PLAINS...70S AND 80S HIGH VALLEYS...AND 50S TO 70S MOUNTAINS. MODELS SUGGEST CONVECTION WILL LINGER INTO THE OVERNIGHT. TUESDAY...THE UPPER RIDGE IS FORECAST TO BE SHUNTED SOUTH SOME...AND THE MOISTURE TAP FROM THE SUBTROPICS WILL STILL BE OVER THE CWA. SO...ANOTHER ROUND OF ISOLATED TO SCATTERED AFTERNOON AND EVENING SHOWERS AND STORMS WILL PERSIST. HIGH TEMPERATURES WILL BE SIMILAR TO MONDAYS READINGS. WEDNESDAY...A SHORTWAVE IS FORECAST TO EJECT OUT OF THE WESTERN TROUGH BUT IT SHOULD BE CENTERED FAR TO OUR NORTH. STILL...ANOTHER SHOT OF AFTERNOON AND EVENING SHOWERS AND STORMS WILL OCCUR WITH THE MOISTURE IN PLACE AND SOME FORCING ALOFT. THURSDAY THROUGH SATURDAY...AS THE NORTHERN SHORTWAVE PUSHES EAST INTO THE UPPER MIDWEST AND GREAT LAKES...THE UPPER RIDGE WILL RETROGRADE SOME TO THE WEST...AND THE ROCKIES WILL SEE ZONAL FLOW AND A LITTLE MORE SETTLED WEATHER. DURING THE AFTERNOON AND EVENING THERE WILL BE CHANCES FOR HIGHER ELEVATION SHOWERS AND STORMS. TEMPERATURE WILL CONTINUE TO BE NEAR NORMAL FOR JULY. OF COURSE...THERE IS ALWAYS THE THREAT FOR STRONGER STORMS TO IMPACT BURN SCARS...SO THAT WILL BE CLOSELY WATCHED. -TLM- && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 247 PM MDT SAT JUL 11 2015 VFR CONDITIONS CAN BE EXPECTED AT THE TAF SITE TONIGHT THROUGH SUNDAY. THERE IS A SMALL CHANCE THAT A TSTM COULD MOVE INTO THE VCNTY OF KCOS OR KALS THIS EVENING. SUNDAY AFTERNOON KALS COULD SEE A TSTM IN THE VCNTY BUT CHANCES ARE LOW. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...28 LONG TERM...TM AVIATION...28
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1138 AM MDT SAT JUL 11 2015 .UPDATE... ISSUED AT 739 AM MDT SAT JUL 11 2015 SHOWERS AND THUNDERSTORMS ALREADY DEVELOPING TO OUR SOUTHWEST THIS MORNING WITH LIGHTNING ACTIVITY PICKING UP IN THE VICINITY OF LAKE POWELL ON EDGE ON WEAK WAVE LIFTING NORTHEAST. ECMWF AND RUC SEEMS TO HAVE THE BEST HANDLE ON THIS MINOR RIPPLE LIFTING IT NORTHEAST AND WEAKENING OVER THE NEXT FEW HOURS. A SECONDARY WAVE LOOKS TO SPIN UP AROUND NOON...WITH MORE ACTIVITY LIFTING ACROSS MESA COUNTY AND INTO THE NORTHWEST PORTIONS OF THE FORECAST AREA. HAVE ADJUST POPS TO FIT CURRENT SITUATION AND BOOSTED VALUES UP A BIT THIS AFTERNOON. NO OTHER CHANGES WERE MADE TO THE GRIDS. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 400 AM MDT SAT JUL 11 2015 FORECAST PWATS REMAIN SOMEWHAT HIGH TODAY WITH VALUES OF AN INCH OR JUST ABOVE FAVORED IN THE RAP AND NAM WHILE GFS AND SREF PUT VALUES BETWEEN .75 TO .9 INCHES. THE LOCATION OF THE HIGH PRESSURE OVER TX AND AND TROUGH OFF THE WEST COAST STILL LOOKS FAVORABLE FOR MOISTURE TO CONTINUE TO ADVECT IN FROM THE SOUTH. NAM12 AND GFS IN PRETTY GOOD AGREEMENT THAT CONVECTION WILL FIRE IN THE FOUR CORNERS AROUND NOON AND OVERSPREAD THE AREA TO THE NORTHEAST. THE JET STREAM IS LOCATED FROM SRN CALIF...UP THROUGH LAS VEGAS AND CENTRAL UTAH WHICH WILL INCREASE ASCENT AND ALSO DIVERGENCE ALOFT WHICH IS ALWAYS HELPFUL IN CONVECTION. STRONGER STORMS AND SHOWERS THAT FORM WILL BRING HEAVY RAIN...SMALL HAIL AND SOME GUSTY WINDS...SIMILAR TO WHAT WE`VE SEEN ALL WEEK. SOME CONVECTION WILL CONTINUE THROUGH MIDNIGHT WITH VERY ISOLD CONVECTION AFTER THAT. THE TRICKY PART OF THE FORECAST IS SUNDAY. THE NAM PAINTS AN ALMOST COMPLETELY DRY DAY FOR THE CWA WHILE THE GFS FAVORS THE SAN JUANS AND AREAS SOUTH FOR MORE PRECIP. NOT SOLD ON NAM AS AVAILABLE MOISTURE...THOUGH LOWER...WILL STILL REMAIN AND THOUGH THE MOST ENERGETIC PART OF THE JET STREAM SHIFTS TO THE PLAIN STATES...ENOUGH SUPPORT MAY ALLOW SOME RAIN TO FALL. WITH THAT IN MIND...KEPT SCHC CONVECTION IN FORECAST FOR QUITE A BIT OF THE FORECAST AREA. MIGHT BE A BIT MUCH BUT WE CAN TRIM THE FORECAST AS NEWER MODELS COME IN. TEMPS START TO RISE BUT WILL REMAIN BELOW CLIMO. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 400 AM MDT SAT JUL 11 2015 MODELS ASSERT THAT THE LARGE SCALE PATTERN WILL REMAIN LARGELY UNCHANGED DURING THE EARLY PART OF THE COMING WEEK. CONSEQUENTLY ...EXPECT THE MONSOONAL SURGE WILL CONTINUE AS SUBTROPICAL MOISTURE IS DRAWN NORTHEASTWARD ACROSS THE AREA BETWEEN HIGH PRESSURE OVER THE SOUTHERN PLAINS AND A TROUGH OF LOW PRESSURE OVER THE WEST COAST. THE MOISTURE LADEN AIR WILL FUEL MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS FAVORING THE MOUNTAINS. NOCTURNAL STORMS ARE POSSIBLE DURING THIS PERIOD AS MORE SUBTLE FEATURES NOT WELL HANDLED BY LARGE SCALE MODELS MAY COME INTO PLAY. MODELS POINT TO A SHIFT IN THE PATTERN AT MIDWEEK AS ENERGY EJECTED FROM THE WEST COAST TROUGH MOVES EASTWARD OVER THE NORTHERN ROCKIES FLATTENING THE RIDGE. AS THIS OCCURS HIGH PRESSURE OVER THE SOUTHERN PLAINS WILL EXPAND WESTWARD CUTTING OFF THE INFLUX OF MOISTURE. DRIER AIR IN WESTERLY FLOW WILL ERODE THE MOISTURE OVER THE AREA DURING THE LATTER PART OF THE WEEK BRINGING A DECREASE IN AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS AS EARLY AS WEDNESDAY. MODELS DIFFER IN TIMING WITH GFS FASTER WITH THIS EVOLUTION...BUT BY THE END OF THE WEEK MODELS WERE IN AGREEMENT WITH GREATLY REDUCED MOIST CONVECTION. TEMPERATURES WILL REMAIN SUPPRESSED BY CLOUDS AND SHOWER ACTIVITY DURING THE EARLY PART OF THE WEEK SO EXPECT BELOW NORMAL VALUES TO CONTINUE. DRIER AIR TRANSLATES INTO GREATER SOLAR INSOLATION DURING THE LATTER HALF OF THE COMING WEEK AND AFTERNOON HIGHS WILL TREND UPWARD AS RESULT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1136 AM MDT SAT JUL 11 2015 SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS WESTERN COLORADO AND EASTERN UTAH THROUGH 02Z THIS EVENING. ACTIVITY WILL DIMINISH AFTER 02Z. GUSTY WINDS TO NEAR 45 KTS...SMALL HAIL AND BRIEF HEAVY RAINFALL WILL ACCOMPANY THE FAST MOVING STORMS. EXPECT ILS CIGS NEAR SHOWERS AND THUNDERSTORMS WITH MOUNTAIN TOPS BECOMING OBSCURED. AWAY FROM SHOWERS...VFR CONDS WILL PREVAIL. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...NONE. UT...NONE. && $$ UPDATE...JDC SHORT TERM...TGR LONG TERM...NL AVIATION...JDC
AREA FORECAST DISCUSSION
NWS LINCOLN IL
340 PM CDT SAT JUL 11 2015 .SHORT TERM...(TONIGHT) ISSUED AT 325 PM CDT SAT JUL 11 2015 CONVECTIVE SYSTEM CONTINUES TO MARCH EAST WITH CELLS PROPAGATING SOUTHEAST INTO A MUCH MORE UNSTABLE ATMOSPHERE ALONG THE SOUTHWEST FLANK OF THE STORMS THIS AFTERNOON. EXPECT THE CLUSTER OF STORMS TO PUSH EAST-SOUTHEAST AND BE BASICALLY TO OUR EAST AND SOUTH BY 02Z/9PM. THEN THE MAIN CHALLENGE WILL BE WITH ANY ADDITIONAL DEVELOPMENT ALONG THE WARM FRONT AND ANY NEED FOR A FLASH FLOOD WATCH FOR AT LEAST THE NORTHERN HALF OF THE FORECAST AREA. BASED ON THE PAST FEW RUNS OF THE HRRR MODEL AND 18Z NAM...IT APPEARS THE BULK OF THE RAINFALL WILL BE WITH THE AFTERNOON STORMS WITH THE HI-RES/CONVECTIVE ALLOWING MODELS NOT SHOWING ANY SIGNIFICANT DEVELOPMENT LATE THIS EVENING. HOWEVER...THE LATEST ECMWF AND TO SOME EXTENT THE GFS DOES SHOW DEVELOPMENT LATER THIS EVENING INTO THE OVERNIGHT HOURS ACROSS THE NORTH...IN AREAS THAT CAN NOT TAKE ANY MORE RAINFALL (ROUGHLY NORTH OF A JACKSONVILLE TO SPRINGFIELD TO CHAMPAIGN LINE). WILL GO AHEAD AND ISSUE A FLASH FLOOD WATCH FOR TONIGHT INTO SUNDAY MORNING IN AREAS THAT HAVE THE LOWEST FLASH FLOOD GUID VALUES. KNOX COUNTY HAS ALREADY RECEIVED FROM 1 TO 2 INCHES OF RAIN TODAY WITH AREAS FURTHER EAST NOW SEEING THE RAINFALL...SO ANY ADDITIONAL RAINS ACROSS THE NORTH WILL POSE A SIGNIFICANT FLASH FLOOD THREAT TONIGHT INTO SUNDAY MORNING. && .LONG TERM...(SUNDAY THROUGH SATURDAY) ISSUED AT 325 PM CDT SAT JUL 11 2015 SEVERAL STORM COMPLEXES/MCS AND POSSIBLE BOW ECHO LATE SUNDAY NIGHT AND ESPECIALLY ON MONDAY/MONDAY EVENING AS MODELS DEPICT AN EXTREMELY UNSTABLE ATMOSPHERE IN PLACE OVER CENTRAL ILLINOIS MONDAY AFTERNOON AND EVENING. MIXED LAYER CAPES OF 3000-3500 ON SUNDAY ACROSS THE WEST WITH MOST OF THE AREA SEEING 4000 J/KG MIXED LAYER CAPES MONDAY AFTERNOON AND EVENING WITH BULK SHEAR VALUES OF 35-45KTS. EXACT TIMING AND LOCATION THIS FAR OUT TOUGH TO PIN DOWN BUT THE POTENTIAL IS THERE FOR A SWATH OF WIDESPREAD DAMAGING WIND GUSTS AND ISOLATED TORNADOES MONDAY AFTERNOON AND EVENING. THE THREAT ON SUNDAY APPEARS TO BE MORE WITH DAMAGING WIND GUSTS FROM STORM CLUSTERS THE FORM TO OUR NORTHWEST AND SWEEP SOUTHEAST INTO THE UNSTABLE AIR MASS. MOST OF THE MEDIUM RANGE MODELS SUGGEST THE STRONGER SHORTWAVE TO TRACK ACROSST THE GREAT LAKES LATE MONDAY NIGHT BRINGING A COOL FRONT SOUTHEAST INTO THE AREA TEMPORARILY PUTTING AN END TO THE THREAT FOR WIDESPREAD RAINFALL AND SEVERE STORMS TUESDAY AFTERNOON THRU WEDNESDAY...BEFORE ANOTHER SHORTWAVE APPROACHES THE AREA LATE WED INTO THU ACCOMPANIED BY SCATTERED THUNDERSTORM CHANCES INTO THE END OF THE WEEK. ANOTHER CONCERN WILL BE WITH HEAT INDEX VALUES IN OUR WEST AND SOUTHWEST TOMORROW AFTERNOON AND CWA WIDE ON MONDAY WHEN VALUES WILL RANGE FROM 100-105. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1227 PM CDT SAT JUL 11 2015 TIMING OF THUNDERSTORMS IS THE MOST SIGNIFICANT CHALLENGE FOR THIS FORECAST. LINE OF CONVECTION CURRENTLY INTENSIFYING FROM NEAR KUIN-KGBG MOVING EAST-SOUTHEAST AND WILL BE AFFECTING THE CENTRAL ILLINOIS TAF SITES OVER THE NEXT FEW HOURS. FOCUSED SOME TEMPO PERIODS FOR IFR CONDITIONS IN THE TAF`S FOR THE PASSAGE OF THE LINE ITSELF. THERE IS LIKELY TO BE A PERIOD OF DRY CONDITIONS BEHIND THE INITIAL CONVECTION BEFORE MORE FORMS TONIGHT. HOWEVER...DO NOT HAVE MUCH CONFIDENCE IN NARROWING DOWN A SPECIFIC TIME FRAME YET...SO WILL KEEP MENTION AS VCTS FOR NOW. HAVE INDICATED SOME DRIER CONDITIONS LATE IN THE PERIOD THOUGH. && .ILX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR ILZ027>031- 036>038-040>043-047-048. && $$ SHORT TERM...SMITH LONG TERM...SMITH AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1227 PM CDT SAT JUL 11 2015 .UPDATE... ISSUED AT 1000 AM CDT SAT JUL 11 2015 UPDATED THE FORECAST TO INCREASE THE RAIN CHANCES THIS MORNING AND REFINE SOME OF THE TRENDS. BULK OF THE OVERNIGHT CONVECTION IS CURRENTLY ACROSS THE SOUTHEAST HALF OF IOWA...ALTHOUGH IT IS ALSO SHOWING AN EASTWARD PROGRESSION AND WILL BE AFFECTING THE NORTHERN THIRD OF THE FORECAST AREA OVER THE NEXT FEW HOURS. ATTACHED WING OF SHOWERS EXTENDS SOUTHEAST AND HAS BEEN WEAKENING...BUT WILL BE AFFECTING EAST CENTRAL ILLINOIS THROUGH MIDDAY. LATEST HRRR TRYING TO DEVELOP ADDITIONAL CONVECTION ACROSS WEST CENTRAL ILLINOIS SHORTLY AFTER MIDDAY. SOME ENHANCEMENT IN THE CUMULUS IS CURRENTLY STARTING TO APPEAR ACROSS NORTHERN MISSOURI WHERE THERE IS SOME CLEARING...AND THIS IS LIKELY WHAT THE HRRR IS PICKING UP ON. HAVE CONTINUED WITH THE HIGHER POP`S ACROSS THE NORTHERN CWA WITH THE MCS...BUT MAY NEED TO BUMP UP THE SOUTHERN AREAS ONCE THE CONVECTIVE TRENDS CAN BE ESTABLISHED. && .SHORT TERM...(TODAY) ISSUED AT 334 AM CDT SAT JUL 11 2015 WARM FRONTAL BOUNDARY LIFTING ACROSS CENTRAL IL AND SHORTWAVE TROUGH PASSING THROUGH NORTHERN IL TODAY WILL BE THE FOCUS FOR THUNDERSTORM ACTIVITY THROUGH THE EARLY PART OF THE DAY AS SUBSTANTIAL MOISTURE ADVECTS INTO THE AREA CHARACTERIZED BY PRECIPITABLE WATER AROUND 2 INCHES AND DEWPOINTS INTO THE 70S. A FEW THUNDERSTORMS ALREADY DEVELOPING IN THE EARLY MORNING IN WEST CENTRAL IL AS A RESULT OF ELEVATED INSTABILITY. THE SHORTWAVE CURRENTLY APPEARS TIMED FOR LATE MORNING TO EARLY AFTERNOON...WITH A POTENTIAL GAP IN THUNDERSTORM ACTIVITY FOR MID AFTERNOON AS ANOTHER SHORTWAVE APPROACHES THE NORTHERN PORTION OF THE STATE FROM THE WEST...BRINGING HIGHER CHANCES AGAIN FOR LATE AFTERNOON/EARLY EVENING. THIS LATER ROUND OF STORMS COULD BE QUITE STRONG AS MLCAPE VALUES AROUND 2000-2500 J/KG ARE FORECAST TO DEVELOP BY 00Z OVER CENTRAL IL. 0-6 KM BULK SHEAR EXPECTED TO REMAIN ONLY AROUND 25 KTS. SEVERE WEATHER THREATS WILL BE POTENTIAL FOR LOCALIZED DAMAGING WIND GUSTS AND HAIL...FOR WHICH SPC HAS A MARGINAL (5%) RISK IN MUCH OF CENTRAL/NORTHERN IL. POPS TODAY GENERALLY RANGING FROM CHANCE TO LIKELY IN THE NORTHWESTERN PORTIONS OF THE CENTRAL IL FORECAST AREA...RANGING DOWN TO SLIGHT CHANCE IN THE SOUTHEAST TO REFLECT ABOVE REASONING. HIGH TEMPERATURES HAVE BEEN TRENDED DOWN A FEW DEGREES TO THE LOW TO MID 80S DUE TO PREVALENT CLOUD COVER AND SHOWERS/THUNDERSTORMS. .LONG TERM...(TONIGHT THROUGH FRIDAY) ISSUED AT 334 AM CDT SAT JUL 11 2015 MCS TO TRACK SE ACROSS CENTRAL/NORTHERN IL TONIGHT AND INCREASED CHANCES OF SHOWERS AND THUNDERSTORMS. SPC HAS MARGINAL RISK OF SEVERE STORMS NORTH OF I-70 FOR 5% RISK OF DAMAGING WINDS AND LARGE HAIL. FRONTAL BOUNDARY TO SET UP JUST NE OF CENTRAL IL NEXT FEW DAYS AND WILL HAVE DISTURBANCES TRACKING SE ALONG BOUNDARY BRINGING GOOD CHANCES OF SHOWERS AND THUNDERSTORMS WITH NOCTURNAL LOW LEVEL JET AND VERY UNSTABLE AIR MASS AIDING IN THUNDERSTORMS DEVELOPMENT. HEAVY RAINS ALSO POSSIBLE WITH PRECIPITABLE WATER VALUES NEAR 2 INCHES. WILL WET GROUND HAVE TRIMMED HIGHS A FEW DEGREES NEXT FEW DAYS BUT STILL HIGHS IN UPPER 80S TO AROUND 90F SUNDAY AND UPPER 80S/LOWER 90S MON. WITH DEWPOINTS CLIMBING INTO THE 70S AFTERNOON HEAT INDICES TO RISE TO 95-100F SUNDAY AFTERNOON AND 99-104F MONDAY AFTERNOON WHICH IS JUST SHY OF HEAT ADVISORY CRITERIA OF 105F. SPC SHOWS A SLIGHT CHANCE OF SEVERE STORMS SUNDAY AFTERNOON INTO SUNDAY NIGHT WITH ANOTHER MCS TRACKING SE FROM UPPER MS RIVER VALLEY SUNDAY NIGHT. MEANWHILE ENHANCED RISK OF SEVERE STORMS MONDAY AFTERNOON/EVENING FOR DAMAGING WINDS...LARGE HAIL AND POSSIBLE TORNADOES. VERY UNSTABLE AIRMASS WITH CAPES OF 3-4K J/KG SUNDAY AFTERNOON AND 4-6K J/KG MONDAY AFTERNOON. 00Z FORECAST MODELS CONTINUE TO SHOW AN ACTIVE WEATHER PATTERN OVER IL THROUGH MIDDLE AND LATER PART OF NEXT WEEK WITH DAILY CHANCES OF SHOWERS AND THUNDERSTORMS IN A WARM AND HUMID AIRMASS. SERIES OF SHORT WAVES TO RIDE OVER TOP OF UPPER LEVEL RIDGE (CENTERED OVER THE SOUTHERN PLAINS) THAT WILL TRACK NEAR IL WHICH IS IN WNW UPPER LEVEL FLOW. A COLD FRONT TO TRACK SE THROUGH IL SOMETIME NEXT WEEKEND AND CONTINUES CHANCES OF SHOWERS/THUNDERSTORMS. HIGHS IN THE 80S WITH SOUTHEAST IL NEAR 90 AT TIMES WHILE LOWS CLOSE TO MUGGY DEWPOINTS IN THE UPPER 60S TO MID 70S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1227 PM CDT SAT JUL 11 2015 TIMING OF THUNDERSTORMS IS THE MOST SIGNIFICANT CHALLENGE FOR THIS FORECAST. LINE OF CONVECTION CURRENTLY INTENSIFYING FROM NEAR KUIN-KGBG MOVING EAST-SOUTHEAST AND WILL BE AFFECTING THE CENTRAL ILLINOIS TAF SITES OVER THE NEXT FEW HOURS. FOCUSED SOME TEMPO PERIODS FOR IFR CONDITIONS IN THE TAF`S FOR THE PASSAGE OF THE LINE ITSELF. THERE IS LIKELY TO BE A PERIOD OF DRY CONDITIONS BEHIND THE INITIAL CONVECTION BEFORE MORE FORMS TONIGHT. HOWEVER...DO NOT HAVE MUCH CONFIDENCE IN NARROWING DOWN A SPECIFIC TIME FRAME YET...SO WILL KEEP MENTION AS VCTS FOR NOW. HAVE INDICATED SOME DRIER CONDITIONS LATE IN THE PERIOD THOUGH. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEELHART SHORT TERM...ONTON LONG TERM...07 AVIATION...GEELHART
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
235 PM EDT SAT JUL 11 2015 .UPDATE... THE LONG TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 1012 AM EDT SAT JUL 11 2015 HIGH PRESSURE WILL SHIFT EAST OF THE REGION BY LATE DAY. AFTER THAT LOW PRESSURE WILL DEVELOP OVER THE PLAINS AND SLOWLY HEAD EAST...CAUSING VERY WARM HUMID AIR TO FLOW ACROSS OUR STATE. EVENTUALLY THE LOW PRESSURE SHOULD BECOME ASSOCIATED WITH A COLD FRONT...WHICH IS FORECAST TO CROSS THE HOOSIER STATE FROM TUESDAY INTO WEDNESDAY. FOR THURSDAY INTO FRIDAY HIGH PRESSURE IS EXPECTED TO TRAVERSE INDIANA FROM WEST TO EAST. THIS WILL CAUSE ANOTHER FLOW OF WARM HUMID AIR BY THE WEEKEND. && .NEAR TERM /REST OF TODAY/... ISSUED AT 1012 AM EDT SAT JUL 11 2015 PATCHY DENSE FOG HAS NOW ALL BUT BURNED OFF ACROSS THE REGION... WITH THE WELCOME SIGHT OF THE SUN AS WEAK HIGH PRESSURE DRIFTS SLOWLY EAST. 14Z TEMPS GENERALLY RANGE FROM THE UPPER 60S TO LOWER 70S. CLOUD DEBRIS ASSOCIATED WITH CONVECTION FROM CENTRAL ILLINOIS BACK INTO SOUTHERN IOWA ALREADY EXPANDING INTO THE WESTERN FORECAST AREA AND WILL DIMINISH SUNSHINE UNFORTUNATELY INTO THE AFTERNOON. AIRMASS OVER THE REGION IS QUITE A BIT MORE STABLE THAN AREAS FURTHER WEST...SO EXPECTATION IS THAT ONGOING STORMS OVER CENTRAL INDIANA WILL WEAKEN AS THEY APPROACH THE WABASH VALLEY AROUND MIDDAY. HRRR AND NMM-WRF BOTH HAVE A VERY GOOD HANDLE ON THIS THINKING AND WAS UTILIZED FOR POPS INTO THE AFTERNOON. WILL INTRODUCE SCHC POPS INTO THE NORTHERN HALF OF THE WABASH VALLEY BY 17Z WITH A SLOW EASTWARD EXPANSION THEREAFTER. STILL THINK BETTER CHANCE FOR CONVECTION WILL HOLD OFF UNTIL LATE AFTERNOON AT THE EARLIEST AND OVERNIGHT FOR MOST. INSTABILITY AND PRECIP WATER VALUES WILL INCREASE GRADUALLY BY LATE AFTERNOON AS THE REMNANT FRONTAL BOUNDARY APPROACHES...WITH HIGHEST VALUES RESIDING IN THE WABASH VALLEY BY LATE DAY. SOME UNCERTAINTY EXISTS IN HOW CONVECTION WILL REDEVELOP LATER ON OUT WEST WITH SOME HINTS AT INITIATION ACROSS NORTHEAST MISSOURI AND CENTRAL ILLINOIS ALONG THE INSTABILITY GRADIENT AND AT THE NOSE OF THE LOW LEVEL JET...WITH ADDITIONAL DEVELOPMENT DURING THE EVENING OVER NORTHERN ILLINOIS AIDED BY THE JET. STILL ANTICIPATE THIS ACTIVITY TO RIDE THE INSTABILITY GRADIENT AND REMNANT BOUNDARY INTO THE AREA TONIGHT WITH STRONG STORMS AND HEAVY RAIN POTENTIAL. LOWERED HIGH TEMPS SLIGHTLY WITH EXPECTED CLOUD COVERAGE LATER ON TODAY. ZONE AND GRID UPDATES OUT. && .SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/... ISSUED AT 250 AM EDT SAT JUL 11 2015 AS FOR SOME TIME...PRECIPITATION IS THE MAIN ISSUE. ALL MODELS HAVE THE CWA UNDER POSITIVE ADVECTION OF WET BULB POTENTIAL TEMPERATURE TONIGHT. THIS IS LIABLE TO FIRE A CONVECTIVE SYSTEM. THE MODELS REFLECT THIS FAIRLY WELL IN THEIR WET POPS. THE PRECIPITABLE WATER DOESNT LOOK QUITE ENOUGH FOR WIDESPREAD HEAVY RAIN AND A FLOOD WATCH TONIGHT. IT IS ENOUGH TO MENTION LOCALLY HEAVY RAIN. SUNDAY INTO TUESDAY NIGHT THINGS GET COMPLICATED. THERE IS A LOT OF DISAGREEMENT BETWEEN ON THE MODELS ON THE LOCATION OF SUBTLE FEATURES THAT WILL DRIVE CONVECTION. WITH THAT UNCERTAINTY...CHANCE POPS SEEM BEST MOST OF THE TIME. GIVEN THE UNCERTAINTY ABOUT POPS THERE IS ALSO UNCERTAINTY ABOUT TEMPERATURES. ON AVERAGE...A CONSENSUS FORECAST IS THE WAY TO GO IN SUCH SITUATIONS...SO AN CONSENSUS OF THE MAV AND MET WILL BE USED. AN EXCEPTION WILL BE MADE TUESDAY. SLIGHT CUTS WILL BE MADE. ITS HARD TO SEE MANY PLACES HITTING 90 GIVEN THE GROUND SHOULD BE QUITE WET. AN INTERESTING FEATURE ON MONDAY IS THE FORECAST CAPES NOT TOO FAR TO OUR WEST. THEY ARE LITERALLY THE HIGHEST I HAVE EVER SEEN. MONDAY MAY BE AN EXCITING DAY. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... ISSUED AT 235 PM EDT SAT JUL 11 2015 STOP ME IF YOUVE HEARD THIS ONE BEFORE...STORMS WILL BE A THREAT EACH PERIOD THROUGHOUT THE LONG TERM. BROAD RIDGE OF HIGH PRESSURE ACROSS THE SOUTH CENTRAL US LOOKS TO KEEP STORM TRACK NORTH AND ALLOW FOR THE POSSIBILITY OF SEVERAL RIDGE RIDING STORM SYSTEMS TO IMPACT THE AREA THROUGH THE WEEK. THAT IS NOT TO SAY THAT THERE WILL NOT BE SIGNIFICANT DRY PERIODS...BUT STORM CHANCES WILL BE REQUIRED EACH PERIOD THROUGH THE LONG TERM PORTION OF THE FORECAST. TEMPERATURES NEAR CLIMATOLOGICAL NORMALS CAN BE EXPECTED WITH THE AREA ON THE PERIPHERY OF THE RIDGE. CONVECTION WILL HAVE THE POTENTIAL TO SIGNIFICANTLY IMPACT TEMPERATURES BUT WITH VERY HIGH UNCERTAINTY AS TO TIMING...CAN SEE LITTLE REASON TO DEVIATE FROM CONSENSUS NUMBERS AT THIS POINT. && .AVIATION /DISCUSSION FOR THE 11/18Z TAFS/... ISSUED AT 112 PM EDT SAT JUL 11 2015 VFR THROUGH THE PERIOD OUTSIDE OF ANY POTENTIAL THUNDERSTORMS. EXPECT A QUIET AFTERNOON TO CONTINUE ACROSS CENTRAL INDIANA...ALTHOUGH SHORT TERM GUIDANCE NOW INDICATES THAT CONVECTIVE ACTIVITY OVER WESTERN ILLINOIS MAY GET INTO THE SITES EARLIER THAN PREVIOUSLY FORECAST. WILL MOVE SHOWER/VCTS MENTION UP A FEW HOURS. HOWEVER...ONCE IT IS IN WILL KEEP IT IN FOR THE DURATION. RESTRICTIONS WILL LIKELY OCCUR AT TIMES WHEN SHOWERS/THUNDERSTORMS IMPACT THE SITES BUT THESE IMPACTS ARE FAR TOO UNCERTAIN FOR MENTION AT THIS POINT. WINDS WILL BE 10KT OR LESS THROUGHOUT THE PERIOD. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...JK/RYAN NEAR TERM...RYAN SHORT TERM...JK LONG TERM...NIELD AVIATION...NIELD VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
112 PM EDT SAT JUL 11 2015 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 1012 AM EDT SAT JUL 11 2015 HIGH PRESSURE WILL SHIFT EAST OF THE REGION BY LATE DAY. AFTER THAT LOW PRESSURE WILL DEVELOP OVER THE PLAINS AND SLOWLY HEAD EAST...CAUSING VERY WARM HUMID AIR TO FLOW ACROSS OUR STATE. EVENTUALLY THE LOW PRESSURE SHOULD BECOME ASSOCIATED WITH A COLD FRONT...WHICH IS FORECAST TO CROSS THE HOOSIER STATE FROM TUESDAY INTO WEDNESDAY. FOR THURSDAY INTO FRIDAY HIGH PRESSURE IS EXPECTED TO TRAVERSE INDIANA FROM WEST TO EAST. THIS WILL CAUSE ANOTHER FLOW OF WARM HUMID AIR BY THE WEEKEND. && .NEAR TERM /REST OF TODAY/... ISSUED AT 1012 AM EDT SAT JUL 11 2015 PATCHY DENSE FOG HAS NOW ALL BUT BURNED OFF ACROSS THE REGION... WITH THE WELCOME SIGHT OF THE SUN AS WEAK HIGH PRESSURE DRIFTS SLOWLY EAST. 14Z TEMPS GENERALLY RANGE FROM THE UPPER 60S TO LOWER 70S. CLOUD DEBRIS ASSOCIATED WITH CONVECTION FROM CENTRAL ILLINOIS BACK INTO SOUTHERN IOWA ALREADY EXPANDING INTO THE WESTERN FORECAST AREA AND WILL DIMINISH SUNSHINE UNFORTUNATELY INTO THE AFTERNOON. AIRMASS OVER THE REGION IS QUITE A BIT MORE STABLE THAN AREAS FURTHER WEST...SO EXPECTATION IS THAT ONGOING STORMS OVER CENTRAL INDIANA WILL WEAKEN AS THEY APPROACH THE WABASH VALLEY AROUND MIDDAY. HRRR AND NMM-WRF BOTH HAVE A VERY GOOD HANDLE ON THIS THINKING AND WAS UTILIZED FOR POPS INTO THE AFTERNOON. WILL INTRODUCE SCHC POPS INTO THE NORTHERN HALF OF THE WABASH VALLEY BY 17Z WITH A SLOW EASTWARD EXPANSION THEREAFTER. STILL THINK BETTER CHANCE FOR CONVECTION WILL HOLD OFF UNTIL LATE AFTERNOON AT THE EARLIEST AND OVERNIGHT FOR MOST. INSTABILITY AND PRECIP WATER VALUES WILL INCREASE GRADUALLY BY LATE AFTERNOON AS THE REMNANT FRONTAL BOUNDARY APPROACHES...WITH HIGHEST VALUES RESIDING IN THE WABASH VALLEY BY LATE DAY. SOME UNCERTAINTY EXISTS IN HOW CONVECTION WILL REDEVELOP LATER ON OUT WEST WITH SOME HINTS AT INITIATION ACROSS NORTHEAST MISSOURI AND CENTRAL ILLINOIS ALONG THE INSTABILITY GRADIENT AND AT THE NOSE OF THE LOW LEVEL JET...WITH ADDITIONAL DEVELOPMENT DURING THE EVENING OVER NORTHERN ILLINOIS AIDED BY THE JET. STILL ANTICIPATE THIS ACTIVITY TO RIDE THE INSTABILITY GRADIENT AND REMNANT BOUNDARY INTO THE AREA TONIGHT WITH STRONG STORMS AND HEAVY RAIN POTENTIAL. LOWERED HIGH TEMPS SLIGHTLY WITH EXPECTED CLOUD COVERAGE LATER ON TODAY. ZONE AND GRID UPDATES OUT. && .SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/... ISSUED AT 250 AM EDT SAT JUL 11 2015 AS FOR SOME TIME...PRECIPITATION IS THE MAIN ISSUE. ALL MODELS HAVE THE CWA UNDER POSITIVE ADVECTION OF WET BULB POTENTIAL TEMPERATURE TONIGHT. THIS IS LIABLE TO FIRE A CONVECTIVE SYSTEM. THE MODELS REFLECT THIS FAIRLY WELL IN THEIR WET POPS. THE PRECIPITABLE WATER DOESNT LOOK QUITE ENOUGH FOR WIDESPREAD HEAVY RAIN AND A FLOOD WATCH TONIGHT. IT IS ENOUGH TO MENTION LOCALLY HEAVY RAIN. SUNDAY INTO TUESDAY NIGHT THINGS GET COMPLICATED. THERE IS A LOT OF DISAGREEMENT BETWEEN ON THE MODELS ON THE LOCATION OF SUBTLE FEATURES THAT WILL DRIVE CONVECTION. WITH THAT UNCERTAINTY...CHANCE POPS SEEM BEST MOST OF THE TIME. GIVEN THE UNCERTAINTY ABOUT POPS THERE IS ALSO UNCERTAINTY ABOUT TEMPERATURES. ON AVERAGE...A CONSENSUS FORECAST IS THE WAY TO GO IN SUCH SITUATIONS...SO AN CONSENSUS OF THE MAV AND MET WILL BE USED. AN EXCEPTION WILL BE MADE TUESDAY. SLIGHT CUTS WILL BE MADE. ITS HARD TO SEE MANY PLACES HITTING 90 GIVEN THE GROUND SHOULD BE QUITE WET. AN INTERESTING FEATURE ON MONDAY IS THE FORECAST CAPES NOT TOO FAR TO OUR WEST. THEY ARE LITERALLY THE HIGHEST I HAVE EVER SEEN. MONDAY MAY BE AN EXCITING DAY. && .LONG TERM /TUESDAY THROUGH FRIDAY/... ISSUED AT 227 AM EDT SAT JUL 11 2015 AN ACTIVE PATTERN WILL CONTINUE THROUGH THE LONG TERM AS AN UPPER RIDGE COVERING THE CENTRAL U.S. BROADENS AND FLATTENS OUT. THIS WILL ALLOW A SERIES OF WEAK UPPER WAVES TO MOVE THROUGH MAIN FLOW. MODELS ARE IN GOOD AGREEMENT ON THIS OVERALL PATTERN BUT DIFFER ON THE TIMING OF THESE PERTURBATIONS...AND THUS WILL CONTINUE WITH INITIALIZATION RESPONSE OF INCLUDING CHANCES FOR THUNDERSTORMS THROUGHOUT THE LONG TERM. THAT SAID STILL EXPECT DRY TIMES DURING THE LONG TERM...JUST UNABLE TO PIN THEM DOWN AT THIS POINT. INITIALIZATION KEEPS HIGH TEMPERATURES NEAR NORMAL IN THE MIDDLE 80S AND SAW NO REASON TO DEVIATE FROM THIS...ALTHOUGH NOT HIGH CONFIDENCE IN THESE GIVEN THE POTENTIAL FOR RAINFALL TO DECREASE THEM WHEN IT DEVELOPS. && .AVIATION /DISCUSSION FOR THE 11/18Z TAFS/... ISSUED AT 112 PM EDT SAT JUL 11 2015 VFR THROUGH THE PERIOD OUTSIDE OF ANY POTENTIAL THUNDERSTORMS. EXPECT A QUIET AFTERNOON TO CONTINUE ACROSS CENTRAL INDIANA...ALTHOUGH SHORT TERM GUIDANCE NOW INDICATES THAT CONVECTIVE ACTIVITY OVER WESTERN ILLINOIS MAY GET INTO THE SITES EARLIER THAN PREVIOUSLY FORECAST. WILL MOVE SHOWER/VCTS MENTION UP A FEW HOURS. HOWEVER...ONCE IT IS IN WILL KEEP IT IN FOR THE DURATION. RESTRICTIONS WILL LIKELY OCCUR AT TIMES WHEN SHOWERS/THUNDERSTORMS IMPACT THE SITES BUT THESE IMPACTS ARE FAR TOO UNCERTAIN FOR MENTION AT THIS POINT. WINDS WILL BE 10KT OR LESS THROUGHOUT THE PERIOD. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...JK/RYAN NEAR TERM...RYAN SHORT TERM...JK LONG TERM...CP AVIATION...NIELD VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
327 PM CDT SAT JUL 11 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 327 PM CDT SAT JUL 11 2015 19Z WATER VAPOR IMAGERY SHOWS THE CENTER OF AN UPPER RIDGE NEAR THE ARLATX REGION. MEANWHILE THERE WERE SEVERAL WAVES OVER THE WEST AND NORTHERN PLAINS. ONE OF THESE WAVES MOVING ON SHORE OVER THE SOUTHERN CA COAST. PROFILER DATA SUGGESTS THERE MIGHT BE A WEAK VORT MAX OVER THE TX PANHANDLE LIFTING NORTHEAST AS WELL. AT THE SURFACE, A WARM FRONT WAS ANALYZED FROM NEAR PHILLIPSBURG KS TO NORTH OF HEBRON AND INTO NORTHERN MO. FOR THIS EVENING, THE MAIN CONCERN IS WHETHER LOW LEVEL CONVERGENCE WILL BE ENOUGH FOR AN ISOLATED STORM OR TWO TO DEVELOP ALONG THE WARM FRONT. THERE CERTAINLY IS ENOUGH INSTABILITY ALONG THE BOUNDARY FOR STORMS TO FORM, AND DEEP LAYER SHEAR OF 30 TO 35 KTS COULD SUPPORT SOME ORGANIZATION TO THE UPDRAFTS. THE HRRR IS THE ONLY SOLUTION SHOWING ANY DEVELOPMENT ALONG THE WARM FRONT AND BASED ON LATEST VISIBLE SATELLITE, IT APPEARS CONVERGENCE ALONE MAY NOT BE ENOUGH TO GET STORMS GOING. THERE REMAINS SOME WILDCARDS THOUGH. THE HRRR ALSO WANTS TO DEVELOP AN MCS AND BRING IT INTO NORTHERN CENTRAL KS AFTER MIDNIGHT. WITH STORMS ALREADY FORMING OVER THE HIGH PLAINS, THIS MAY BE A LITTLE MORE PLAUSIBLE. ISENTROPIC SURFACES SHOW SOME LIFT THROUGH THE NIGHT AS THE LOW LEVEL JET INCREASES, HOWEVER THERE IS NOT A LOT OF SATURATED AIR BEING LIFTED. SO I DON`T HAVE A GOOD FEELING FOR WHETHER STORMS WILL HOLD TOGETHER OFF THE HIGHER TERRAIN AND I THINK THERE IS NOT ENOUGH MOISTURE FOR ISENTROPIC LIFT ALONE TO CAUSE SOME ELEVATED STORMS. IN THE END HAVE KEPT A SLIGHT CHANCE FOR STORMS ACROSS THE NORTHERN COUNTIES IN CASE SOMETHING DEVELOPS THIS AFTERNOON OR MOVES IN FROM THE WEST. LOWS TONIGHT SHOULD ONLY FALL INTO THE LOWER AND MID 70S AS SOUTHERLY WINDS CONTINUE TO BRING WARM AIR NORTH. FOR SUNDAY, MODELS INDICATE A LACK OF LARGE SCALE FORCING WHILE 700 MB TEMPS WARM THROUGH THE DAY. SO UNLESS SOMETHING UNEXPECTED HAPPENS, LIKE AN MCS MOVING ACROSS NORTHERN KS IN THE MORNING, THINK THE STRENGTHENING CAP SHOULD PRECLUDE PRECIP CHANCES. MODELS SHOW LIMITED MIXING OF THE BOUNDARY LAYER ACROSS EASTERN KS WHILE NORTH CENTRAL KS COULD MIX TO NEAR 800MB. ADDITIONALLY THERE IS SOME DRY AIR MOVING IN AT 850 WITH DEWPOINT DEPRESSIONS NEAR 15C. SO ACROSS EASTERN KS HIGHS ARE EXPECTED TO BE IN THE LOWER AND MID 90S BUT WITH LESS MIXING SO DEWPOINTS SHOULD REMAIN IN THE LOWER 70S. TEMPS ACROSS NORTH CENTRAL KS SHOULD APPROACH 100 WITH DEEPER MIXING, BUT SHOULD MIX SOME OF THE DRYER AIR TO THE SURFACE. IN THE END, HEAT INDICES ARE STILL EXPECTED TO BE AROUND 105 SUNDAY AFTERNOON ACROSS THE ENTIRE AREA, SO WILL MAINTAIN THE HEAT ADVISORY AS IS. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 327 PM CDT SAT JUL 11 2015 HEAT CONTINUES TO BE THE MAIN CONCERN THROUGH MUCH OF THE REMAINDER OF THE FORECAST. WEAK BOUNDARY LOOKS TO BE A BIT FASTER IN ITS SOUTHEASTWARD TRACK THROUGH THE AREA MONDAY AND MAY KEEP HEAT INDEX VALUES FROM GETTING TOO FAR ABOVE 100, BUT WILL KEEP THE ADVISORY GOING. HEAT INDICES STILL LOOK TO BE WELL INTO ADVISORY AND PERHAPS WARNING LEVELS ALONG AND AHEAD OF THE FRONT THOUGH AS IS USUAL AT THIS RANGE, CONFIDENCE IN TEMPS AND DEWPOINTS IS NOT TERRIBLY HIGH AND JUST HOW MUCH THE POOLED MOISTURE CAN MIX OUT BEING THE PRIMARY IMPACT ON APPARENT TEMPS. THIS ALSO LEADS TO INSTABILITY/CAP VALUES ALONG THE BOUNDARY, THOUGH STILL SEEMS POSSIBLE FOR ISOLATED TO SCATTERED CONVECTION DESPITE WEAK CONVERGENCE. NORTHWEST MID/UPPER FLOW LEADS TO MODERATE SHEAR AND COULD SUPPORT SOME STORM ORGANIZATION FOR NEAR SEVERE HAIL ALONG WITH WIND POTENTIAL. HAVE TRIMMED PRECIP CHANCES IN MAINLY NORTHERN AREAS INTO TUESDAY WITH THE QUICKER FRONT TIMING WITH MORE MORE WIDESPREAD THOUGH STILL MODEST RELIEF TO THE HEAT, ENOUGH TO KEEP ANY EXTENSION TO THE HEAT ADVISORY IN CHECK. THERE APPEARS TO BE DECENT AGREEMENT IN A SLOW-MOVING UPPER WAVE TOPPING THE RIDGE AND ENTERING THE CENTRAL HIGH PLAINS LATE TUESDAY, WITH SOUTHEAST LOW LEVEL FLOW IN PLACE AHEAD OF IT FOR DECENT THUNDERSTORM CHANCES L0CALLY LATE TUESDAY NIGHT INTO WEDNESDAY NIGHT. HAVE MOST LOCATIONS SOMEWHAT COOLER WEDNESDAY IN RESPONSE, WITH RIDGE REGAINING SOME STRENGTH NORTHEASTWARD INTO THE MIDWEST LATE IN THE WEEK LIKELY ALLOWING FOR A WARMING TREND IN THE LATE WEEK. DEWPOINTS AT TO ABOVE THE 70 DEGREE MARK COULD EASILY BRING ABOUT MORE HEAT HEADLINE POTENTIAL BY THEN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1220 PM CDT SAT JUL 11 2015 WITH LIMITED FORCING AND THE FOCUS FOR LOW LEVEL CONVERGENCE HAVING LIFTED NORTH OF THE TERMINALS, THINK DRY WEATHER WILL PREVAIL WITH VFR CONDITIONS. WILL NEED TO WATCH THE LOW LEVEL JET OVERNIGHT AS MODELS PROG 30-35KT AT THE TOP OF THE NOCTURNAL INVERSION. AT THIS TIME, THE SURFACE PRESSURE GRADIENT MAY BE STRONG ENOUGH TO KEEP THE BOUNDARY LAYER FROM DECOUPLING. BECAUSE OF THIS CONFIDENCE IN LLWS DEVELOPING IS TO LOW TO INCLUDE A MENTION JUST YET. && .TOP WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY FROM 11 AM SUNDAY TO 9 PM CDT MONDAY FOR KSZ008>012-020>024-026-034>040-054>056-058-059. && $$ SHORT TERM...WOLTERS LONG TERM...65 AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
329 PM CDT SAT JUL 11 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 328 PM CDT SAT JUL 11 2015 THE INFLUENCE OF THE SOUTHEAST U.S. HIGH PRESSURE RIDGE FINALLY KICKED IN ACROSS THE WFO PAH FORECAST AREA LAST EVENING AND TODAY. MOST OF THE WFO PAH FORECAST AREA SHOULD REMAIN DRY THROUGH LATE AFTERNOON UNDER THE SLIGHT LOW LEVEL SUBSIDENCE INVERSION BUILDING NORTHEAST THROUGH THE AREA. HOWEVER...THERE REMAINS A SHARP THERMAL GRADIENT ACROSS THE INTERSTATE 64 CORRIDOR IN SOUTHEAST ILLINOIS...BENDING SOUTHEAST OVER SOUTHWEST INDIANA AND THE EASTERN PENNYRILE REGION OF WEST KENTUCKY. THIS AREA IS CURRENTLY ALONG AND NORTH OF THE OBSERVED SURFACE WARM FRONT AT 1PM CDT SPRAWLED OVER THE NORTHEAST THIRD OF THE WFO PAH FORECAST AREA. FOR TONIGHT...THE MESOSCALE CONVECTIVE SYSTEM CURRENTLY OVER WEST CENTRAL ILLINOIS WILL LIKELY SEND OUTFLOWS AND SOME UPSHEAR LIFT ALONG AND NORTH OF I-64 LATE THIS AFTERNOON. THIS HAS THE POTENTIAL TO PRODUCE ISOLATED THUNDERSTORM THAT MAY APPROACH SEVERE LIMITS CLOSE TO THE WFO PAH FORECAST AREA. THE MAIN CONCERN WILL BE ELEVATED STORMS OVERNIGHT OVER PARTS OF SOUTHWEST INDIANA. INTRODUCED A MENTION OF LOCALLY HEAVY RAIN INTO THE GRIDS FOR PARTS OF PIKE...WARRICK AND SPENCER COUNTIES IN SOUTHWEST INDIANA. IN COLLABORATION WITH NWS INDIANAPOLIS...DECIDED AGAINST A FLASH FLOOD WATCH IN THIS AREA GIVEN THE LIMITED COVERAGE IN SPACE AND TIME. IT WILL STILL NEED TO BE MONITORED OVERNIGHT. FOR SUNDAY...ADDED A MENTION OF GUSTY WINDS AND HEAVY RAIN TO THE GRIDS FOR ANY THUNDERSTORMS THAT DEVELOP OVER THE NORTHEAST HALF OF THE WFO PAH FORECAST AREA LATE SUNDAY MORNING AND AFTERNOON. VERY ROBUST CAPE FOR UPDRAFTS WITH CONVECTIVE TEMPERATURES SUFFICIENT FOR INITIATION. GIVEN THE SUBTLE INVERSION IN PLACE...THERE MAY BE ENOUGH MIXING/DOWNDRAFT CAPE TO SUPPORT STRONG WIND GUSTS...ESPECIALLY DURING THE AFTERNOON. THERE IS SUPPORT FOR SOME DAMAGING WIND GUSTS (AND POSSIBLY A MICROBURST OR TWO) WITH THIS REGIME IN THE AREA OUTLOOKED BY SPC FOR SUNDAY. THE ONLY COMPLICATING FACTOR WILL BE ANY DELAY IN REACHING CONVECTIVE TEMPERATURE NEAR THE SURFACE OR IN THE BOUNDARY LAYER DUE TO LEFT OVER CLOUD DEBRIS FROM OVERNIGHT CONVECTION. FOR MONDAY...BEST CHANCES FOR SEVERE WILL EXPAND WITH SUFFICIENT CAPE/SHEAR FOR MULTICELL STORMS DEFINITELY CAPABLE OF LARGE HAIL...DAMAGING WINDS AND POSSIBLY A TORNADO OR TWO EAST OF THE MISSISSIPPI RIVER...ESPECIALLY DURING THE AFTERNOON AND EVENING. LEANED CLOSER TO THE 3KM HRRR FOR THE EXTREMELY SHORT TERM CONVECTIVE TRENDS...BLENDING TOWARD THE NAM-WRF GUIDANCE IN THE LONGER TIME PERIODS. HEAT INDEX VALUES WILL COME CLOSE TO HEAT ADVISORY CRITERIA ON SUNDAY...AND POSSIBLY REACHING INTO HEAT ADVISORY CRITERIA OVER PARTS OF SOUTHEAST MISSOURI AND SOUTHWEST ILLINOIS ON MONDAY. HOWEVER...GIVEN CLOUD DEBRIS AND WINDS...WILL HOLD OFF REGARDING ANY ADVISORY AT THIS TIME. WILL HIGHLIGHT IN A HAZARDOUS WEATHER OUTLOOK AND A SPECIAL WEATHER STATEMENT FOR NOW. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 328 PM CDT SAT JUL 11 2015 AT THE BEGINNING OF THE EXTENDED FORECAST PERIOD...A SFC FRONTAL BOUNDARY SHOULD ARRIVE IN THE NE QUADRANT OF THE AREA...DRIVEN BY A MID LEVEL SHRTWV AND FAST NWRLY FLOW ALOFT. THE MED RANGE MODELS SUGGEST SOME SEVERE WEATHER IS POSSIBLE WITH THIS SYSTEM TUE. PCPN CHANCES (HIGHEST IN THE SERN QUADRANT) ASSOCIATED WITH THIS FORCING WILL WANE TUE NIGHT AS THE MID/UPPER FLOW GOES SLIGHTLY ANTI-CYCLONIC...LEAVING WED DRY. BY MIDDAY THU...A SECOND SFC BOUNDARY SHOULD BE IN THE VICINITY OF THE PAH FORECAST AREA...PROVIDING LOW LEVEL FORCING FOR SCATTERED SHOWER AND TSTM DEVELOPMENT ACROSS THE ENTIRE REGION...EXCEPT PERHAPS THE FAR WEST (PARTS OF SERN MO) CLOSER TO A DOMINANT SRN CONUS RIDGE. SOME ATMOSPHERIC INSTABILITY WILL BE PROVIDED BY A MINOR ENERGY IMPULSE IN THE WESTERLIES JUST TO THE NORTH OF IT. THIS EVENT SHOULD END THU NIGHT AS THE FRONTAL BOUNDARY EXITS THE REGION AND THE ANTI- CYCLONIC FLOW ALOFT DOMINATES AGAIN. FOR THE REST OF THE WEEK...RAIN-FREE CONDITIONS ARE EXPECTED. MEANWHILE...HEAT INDICES ARE EXPECTED TO FLIRT WITH THE 105 DEGREE MARK IN SERN MO EARLY IN THE PERIOD. LATER IN THE PERIOD...HEAT INDICES BETWEEN 100 AND 105 SHOULD BECOME COMMON ACROSS THE ENTIRE REGION. && .AVIATION... ISSUED AT 328 PM CDT SAT JUL 11 2015 A FRONTAL BOUNDARY WILL SLOWLY PASS NEWD THROUGH THE NERN HALF OF THE REGION TODAY. GENERALLY LIGHT WINDS SHOULD BE MOSTLY OUT OF THE SW DURING THE DAYLIGHT HOURS BEHIND THE FRONT...AND WILL BE MORE VARIABLE IN DIRECTION IN THE VICINITY OF THE FRONT. THE BEST CHANCE OF PCPN WILL BE IN THE NERN QUADRANT OF THE REGION OVERNIGHT...AS A POSSIBLE TSTM COMPLEX MAY MOVE THROUGH. THERE WAS SOME MODEL DISAGREEMENT ABOUT WHETHER THIS WILL HAPPEN...SO FOR NOW SHOWERS/TSTMS WERE LEFT OUT OF THE KEVV/KOWB TAFS. THIS SCENARIO WILL BE RE-EVALUATED DURING THIS AFTERNOON. SOME IFR FOG IS STILL POSSIBLE OVERNIGHT AT KPAH. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ SHORT TERM...DB LONG TERM...SMITH AVIATION...DB
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1232 PM CDT SAT JUL 11 2015 .DISCUSSION... FOR THE 19Z TAF PACKAGE. && .AVIATION... SCATTERED CU/STRATOCU ACROSS THE REGION PER VISIBLE SATELLITE IMAGERY...WITH RADAR IMAGERY SHOWING ISOLATED SHOWERS AND A TSTM OR TWO OVER THE GULF WATERS AND COASTAL COUNTIES/PARISHES. VFR IS EXPECTED TO PREVAIL...WITH CONVECTION FCST TO REMAIN ISOLATED IN NATURE AS DIURNAL INSTABILITY BATTLES AGAINST MASS SUBSIDENCE ASSOCIATED WITH THE DEEP LAYER RIDGING IN PLACE. INSERTED VCSH AT THE I-10 TERMINALS WHERE HIGHEST...ALBEIT STILL LOW...PROBABILITY RESIDES. 13 && .PREV DISCUSSION... /ISSUED 1047 AM CDT SAT JUL 11 2015/ DISCUSSION...MORNING LCH SOUNDING SHOWING PWAT A FEW TENTHS BELOW THAT OF YESTERDAY MORNING. STILL SUFFICIENT MOISTURE FOR ISOLATED AFTERNOON CONVECTION. RADAR JUST NOW DEPICTING A FEW PINPOINT SHOWERS INLAND. FORECAST ON TRACK WITH LOW END POPS. NO UPDATE COMING. PREV DISCUSSION... /ISSUED 650 AM CDT SAT JUL 11 2015/ AVIATION...RIDGING WILL BUILD FROM THE MID LEVELS INTO THE UPPER LEVELS. ALTHOUGH HRRR IS SHOWING WIDELY SCATTERED TSTM ACTIVITY THIS AFTERNOON, WILL OPT TO NOT MENTION IN THE TAFS AS THE COVERAGE LOOKS TO BE ISOLATED FROM ALL THE CONVECTIVE INHIBITION. VFR. SWEENEY PREV DISCUSSION... /ISSUED 240 AM CDT SAT JUL 11 2015/ DISCUSSION... SFC HIGH PRESSURE CONTINUES RIDGING ACROSS THE GULF...WITH A S TO SE FLOW ACROSS THE REGION. RADAR SHOWING A FEW NOCTURNAL SHRA ACROSS THE COASTAL WATERS MOVING ASHORE ACROSS THE COASTAL PARISHES/COUNTIES AND DISSIPATING. LIMITED MOISTURE ALOFT AND FOCUS WILL LIMITED CONVECTION TO ISO DURING THE AFTERNOON HOURS...WITH THE ONGOING 20% STILL LOOKING GOOD FOR THE FORECAST. LOWER/MID 90S FOR HIGHS EXPECTED. THE FORECAST FOR NEXT WEEK LOOKS TO CONTINUE THE HOT AND DRY CONDITIONS DUE TO BUILDING HIGH PRESSURE AT THE SFC AND ALOFT. THE RIDGE WILL INTENSIFY A BIT TOWARDS MON-WED...LIMITING CONVECTION EVEN MORE...BUT TEMPS EXPECTED TO BUMP UP A COUPLE OF DEGREES. MODEL BLEND ONLY SHOWS A SLIGHT INCREASE IN MOISTURE TOWARDS FRI...WITH 20% EXPECTED. OTHERWISE...SLIGHTLY ABOVE NORMAL TEMPS EXPECTED THRU THE PERIOD...MOST NOTABLE FOR LOWS. DML MARINE... SURFACE HIGH PRESSURE RIDGING WESTWARD ACROSS THE NORTHWEST GULF OF MEXICO WILL CONTINUE TO PROVIDE A LIGHT SOUTHERLY FLOW OVER THE NEXT SEVERAL DAYS. && .PRELIMINARY POINT TEMPS/POPS... AEX 94 75 95 76 / 20 10 10 10 LCH 91 77 92 77 / 20 10 10 10 LFT 92 75 93 76 / 20 10 10 10 BPT 91 77 92 76 / 20 10 10 10 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...NONE. TX...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS GAYLORD MI
133 PM EDT SAT JUL 11 2015 .UPDATE... ISSUED AT 1018 AM EDT SAT JUL 11 2015 ANOTHER IDEAL MORNING IN NORTHERN MI. SKIES ARE JUST ABOUT CLEAR...WITH SOME HIGH-BASED CU IN THE GD TRAV BAY REGION...AND IN PARTS OF CENTRAL UPPER MI. THIS IS ASSOCIATED WITH A SUBTLE WARM FRONT ADVANCING EAST NEAR MUNISING/ISQ...AND IS OCCURRING IN THE STEEP LAPSE RATES AT THE TOP OF YESTERDAYS MIXED LAYER. THERE IS STRONG INVERSION PRESENT ABOVE THIS. PER 12Z OBSERVED SOUNDINGS...700MB TEMPS ARE 9C AT APX...10C AT GRB. THIS IS NOT SURPRISING...GIVEN A 500MB SHORTWAVE RIDGE AXIS WILL BE DEAD OVERHEAD THIS AFTERNOON. SO IT WILL TAKE SOME SERIOUS WORK TO OVERCOME THIS CAP. THE 06Z/12Z NAM RUNS BOTH MANAGE TO DO SO...POPPING A STORM IN NE LOWER BY EARLY EVENING. IT MANAGES THIS WHERE CONVERGENCE IS MAXIMIZED (NE MONTMORENCY)...WHERE THE TWO DIFFERENT ORIENTATIONS OF THE LAKE HURON LAKE BREEZE INTERSECT AND MEET THE BACKGROUND SYNOPTIC SW WIND. AN 84/60 SURFACE PARCEL SURFACE PARCEL GENERATES ABOUT 800J/KG OF SBCAPE (AND DOES GET PAST THE CAP)...BUT MLCAPE IS STILL NEGLIGIBLE. AM A TOUCH MORE NERVOUS ABOUT A DRY FORECAST TODAY THAN YESTERDAY...BUT AT THIS POINT STILL BELIEVE DRY IS THE WAY TO GO. (NOTE THE SPC HRRR KEEPS US DRY.) A FAIRLY VIGOROUS CU FIELD WILL BUBBLE UP AWAY FROM THE GREAT LAKES AFTER MIDDAY...IN PARTICULAR NE LOWER AND NW CHIPPEWA CO. THAT WILL CERTAINLY NOT PREVENT A WARM AFTERNOON...WITH HIGHS FROM NEAR 80F TO THE MID 80S. && .NEAR TERM...(TODAY THROUGH TONIGHT) ISSUED AT 346 AM EDT SAT JUL 11 2015 ...TURNING UP THE HEAT JUST A LITTLE MORE... HIGH IMPACT WEATHER POTENTIAL: NONE. OVERVIEW: SUBTROPICAL UPPER LEVEL RIDGE CONTINUES TO BUILD ACROSS THE SRN GULF STATES...DOWNSTREAM OF TROUGHINESS ACROSS THE WESTERN CONUS. IN BETWEEN...A FAIR AMOUNT OF HEAT/HUMIDITY IS STREAMING FROM MEXICO UP THROUGH THE PLAINS AND ALONG THE FRONT RANGE OF THE ROCKIES THEN BACK INTO THE PAC NW...WHERE SEVERAL SHOWER/ THUNDERSTORM COMPLEXES ARE ONGOING. FURTHER EAST...HIGH PRESSURE REMAINS IN CONTROL FOR MUCH OF THE EASTERN CONUS...ALTHOUGH A FEW ROUNDS OF SHOWERS ARE ONGOING IN THE MIDWEST AND MID ATLANTIC STATES ALONG SOME SEMBLANCE OF A STALLED FRONT ACROSS THAT REGION. BUT ONCE AGAIN A QUIET AND MILD NIGHT ACROSS THE GREAT LAKES. PATTERN FORECAST: SUBTROPICAL RIDGE WILL CONTINUE TO BUILD WESTWARD TO BE CENTERED OVER TEXAS BY SUNDAY...AND RIDGE AXIS STRETCHING UP INTO THE UPPER MIDWEST. BUT THIS DOES SHIFT AXIS OF HEAT/HUMIDITY INTO THE PLAINS AND MIDWEST AND SETS UP A PROVERBIAL "RING OF FIRE" AND POTENTIAL FOR ONE OR MORE SHOWER/THUNDERSTORM COMPLEXES TO IMPACT THE REGION. MAIN FORECAST CONCERN IN THE SHORTER TERM IS WHETHER OR NOT NRN MICHIGAN CAN "CATCH" ANY PRECIP FROM ONE OF THESE SYSTEMS. SHORT ANSWER IS...PROBABLY NOT. TODAY...NO WORRIES AS SFC HIGH PRESSURE REMAINS THE DOMINATE PLAYER. TAKE YESTERDAYS HIGH TEMPS AND TAG ON ANOTHER FEW DEGREES AS WARMER AIR INCHES IT/S WAY OUT OF THE PLAINS INTO THE WESTERN GREAT LAKES EDGING H8 TEMPS ACROSS NRN MICHIGAN INTO THE 15C TO 16C RANGE BY EVENING. THIS SUGGESTS LOW TO MID 80S FOR MUCH OF THE CWA. BUT PER FORECAST SOUNDINGS WE WILL ALSO SEE ANOTHER ROUND OF SCT-BKN AFTERNOON CU SIMILAR TO YESTERDAY. CERTAINLY NOT OUT OF THE QUESTION THAT WE COULD POP A FEW SHOWERS ACROSS NE LOWER MICHIGAN WHERE LOW LEVEL CONVERGENCE WILL BE GREATEST (AND AS SUGGESTED BY THE 00Z NAM BUT WHICH AGAIN IS OVERDOING SFC DEWPOINTS/INSTABILITY). BUT LIKE YESTERDAY...WILL NOT BE ADDING ANY POPS TO THE FORECAST AT THIS POINT. TONIGHT...FORECAST CONFIDENCE BEGINS TO DWINDLE AS SUBTROPICAL RIDGE CONTINUES TO SHIFT TO OVER TEXAS...FORCING HEAT/MOISTURE AXIS TOWARD THE MIDWEST. NO DOUBT THERE WILL BE ADDITIONAL SHOWER/THUNDERSTORM DEVELOPMENT TODAY FROM THE CENTRAL AND NRN PLAINS INTO THE MIDWEST. QUESTION IS WHETHER ANY OF THAT CAN SNEAK INTO NRN MICHIGAN. AGAIN SHORT ANSWER IS PROBABLY NOT. ALL GUIDANCE KEEPS AXIS OF BEST MOISTURE/INSTABILITY ACROSS THE MIDWEST WHICH IS WHERE CONTINUED FOCUS FOR SHOWERS/STORMS WILL RESIDE THROUGH TONIGHT. AND IN THE ABSENCE OF ANY DECENT SYNOPTIC FORCING TO DRAG SOMETHING THIS FAR NORTH...I JUST DON/T SEE IT. HENCE HAVE REMOVED POPS FROM TONIGHTS FORECAST. && .SHORT TERM...(SUNDAY THROUGH MONDAY NIGHT) ISSUED AT 346 AM EDT SAT JUL 11 2015 HIGH IMPACT WEATHER: NONE FORECAST CHALLENGE: DETERMINING WHEN SHOWERS AND THUNDERSTORMS WILL BE MOST LIKELY. (7/12)SUNDAY...THE FORECAST WAS TOUGH TO DETERMINE AS THE TWO MODELS WERE AT ODDS WITH THE TIMING. HOWEVER, FOR THE SECOND NIGHT IN A ROW, THE ECMWF HAS MANAGED TO PLAY CATCH UP TO THE GFS IDEA. SO HAVE STARTED TO LEAN MORE TO THE GFS IDEAS WITH THE CONVECTION. LOOKING AT THE SFC BASED CAPES OVER THE REGION THE LATE MORNING AND AFTERNOON HAVE AROUND 1000J/KG ON ONE MODEL AND NEARLY 2000J/KG ON THE OTHER. COUPLED WITH THE 500MB SHORTWAVE AND THE DEVELOPING SFC WAVE, WILL PUT THE CHANCE OF THUNDERSTORMS IN THE REGION AS IT LOOKS TO BE SCATTERED. OVERNIGHT DOESN`T LOOK AT GOOD, BUT THERE IS SOME POTENTIAL AS THE INSTABILITY STILL LOOKS OKAY. THE ONE DOWNSIDE TO ALL OF THIS CONVECTION IN THE MODELS IS THAT THE DEWPOINTS OVER THE UPPER GREAT LAKES HAVE BEEN SIGNIFICANTLY LOWER THAN FORECAST IN THE RAW MODELS, SO THIS INSTABILITY MAY BE A FIGMENT OF THE MODELS IMAGINATION. (7/13)MONDAY...WILL CONTINUE TO KEEP THE POPS TO A MINIMUM AS THE DEWPOINTS ON THE MODELS ENDS UP IN THE LOWER 70S. THIS IS RARELY THE CASE IN N MICHIGAN. SO WHILE THERE MAY BE SOME THUNDER, IT IS MORE LIKELY THAT THERE WILL BE SCATTERED SHOWERS. WILL SEE HOW THIS WORKS OUT, BUT FOR NOW WILL KEEP THE FORECAST ON THE LOWER CHANCE SIDE. THIS FORECAST MAY BE A LITTLE TOO WET, BASED ON WHAT WE HAVE SEEN FOR THE YEAR SO FAR. && .LONG TERM...(TUESDAY THROUGH FRIDAY) ISSUED AT 346 AM EDT SAT JUL 11 2015 EXTENDED (TUESDAY THROUGH FRIDAY)...THERE ARE TIMING DIFFERENCES BETWEEN THE MODELS ON TUESDAY, WITH THE GFS PUSHING THE DRY AIR INTO THE UPPER GREAT LAKES SOONER THAN THE ECMWF (TUESDAY NIGHT). HOWEVER, THE BASIC IDEA IS THE SAME, WITH THE SERIES OF WAVES THAT MOVE THROUGH THE FLOW AND BRING CHANCES OF SHOWERS AND THUNDERSTORMS EVERY OTHER DAY OR TWO. TEMPERATURES LOOK TO REMAIN AROUND NORMAL FOR THIS TIME OF YEAR THROUGH THE END OF THE WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 133 PM EDT SAT JUL 11 2015 VFR. LITTLE CHANGE THRU TONIGHT...WITH HIGH PRESSURE PARKED IN THE SOUTHERN GREAT LAKES. CU FIELD WILL LAST THRU THE AFTERNOON...THEN DIMINISH THIS EVENING. WE WILL SEE SOME HIGH CLOUDS TONIGHT...ESPECIALLY IN NW LOWER. THAT RAMPS UP TO THE POTENTIAL FOR A FEW SHRA TOMORROW...BUT MAINLY LATER IN THE DAY. LIGHT SW SURFACE WINDS WILL GIVE WAY TO LAKE BREEZES THIS AFTERNOON. LIGHT WINDS TONIGHT/SUNDAY MORNING. && .MARINE... ISSUED AT 346 AM EDT SAT JUL 11 2015 OVERALL LARGE SCALE SW-S FLOW DEVELOPS ACROSS THE WESTERN GREAT LAKES TODAY AND TONIGHT...ALTHOUGH WINDS CLOSER TO SHORE WILL BE ONCE AGAIN HEAVILY INFLUENCED BY LAKE BREEZES THIS AFTERNOON. BUT WIND SPEEDS SHOULD REMAIN 10 KNOTS OR LESS ACROSS THE REGION. A SIMILAR STORY FOR SUNDAY AND SUNDAY ALTHOUGH WINDS MAY INCREASE JUST A BIT MORE HEADING INTO SUNDAY NIGHT AS LOW PRESSURE MOVES TOWARD THE UPPER MIDWEST. BUT NO MARINE HEADLINES ARE ANTICIPATED THROUGH THE WEEKEND. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...NONE. LM...NONE. LS...NONE. && $$ UPDATE...JAZ NEAR TERM...ADAM SHORT TERM...JSL LONG TERM...JSL AVIATION...JAZ MARINE...ADAM
AREA FORECAST DISCUSSION
NWS DULUTH MN
307 PM CDT SAT JUL 11 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 307 PM CDT SAT JUL 11 2015 EVEN THOUGH THERE WAS A RIDGE OF HIGH PRESSURE OVER THE FORECAST AREA AT 19Z...PLENTY OF CUMULUS HAD FORMED AND COVERED THE AREA. A LAKE BREEZE WAS TRYING TO DEVELOP WITH A NE FLOW OFF LAKE SUPERIOR. HOWEVER...LOW LEVEL WAA WAS KEEPING IT FROM PUSHING TOO FAR INLAND. THE FEW SHOWERS THAT HAD FORMED EARLIER HAD DISSIPATED. 17Z HRRR RUN CONTINUES TO DOWNPLAY ANY STORMS FROM DEVELOPING THIS EVENING. AFTER 06Z...MODELS POINT TOWARD AN AREA OF SHOWERS AND THUNDERSTORMS INITIATING OVER THE SOUTHERN TIER OF THE REGION FROM THE BRAINERD LAKES EAST TO THE ST. CROIX RIVER VALLEY. THIS WILL BE ON THE LEADING EDGE OF A WARM FRONT INTERACTING WITH A WEAK SHORT WAVE TROF. WITH THE WAA...THERE IS A POSSIBILITY THAT A CAPPING INVERSION MAY KEEP STORMS FROM HAPPENING. MODEL QPF APPEARS TO BE OVERDONE AND HAVE USED A BLEND OF MODELS FOR QPF AND HAVE POPS TO MATCH. ON SUNDAY...UPPER LEVEL RIDGING BUILDS DURING THE DAY WHICH MAY HAMPER THUNDERSTORMS. HOWEVER...STORMS MAY BE ONGOING EARLY IN THE MORNING BEFORE DISSIPATING BY MID MORNING. HAVE SHOWN THIS TREND WITH POPS. IN THE AFTERNOON...MODELS DISAGREE ON THE IMPACT OF A WEAK SHORT WAVE MOVING OVER THE AREA. A CAPPING INVERSION IS DEVELOPING IN THE AFTERNOON...BUT MODELS DISAGREE ON THE STRENGTH AND PLACEMENT. REGARDLESS...HAVE LOW POPS ALIGNED OVER THE APEX OF THE INVERSION EARLY IN THE AFTERNOON. THERE IS ALSO DISAGREEMENT IN THE LATE AFTERNOON ON THE EVENTUAL BREAKDOWN OF THE INVERSION. USED A CONSENSUS APPROACH TO POPS IN THE LATE AFTERNOON. HUMIDITY WILL BE ON THE INCREASE SUNDAY WITH DEWPOINTS REACHING THE LOWER 70S IN SEVERAL LOCATIONS. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 307 PM CDT SAT JUL 11 2015 A GENERALLY ACTIVE PATTERN COMING UP THIS WEEK WITH SEASONABLE TEMPERATURES ON TAP. THE LONG TERM PERIOD BEGINS WITH THUNDERSTORMS EXPECTED TO BE ONGOING SUNDAY NIGHT BEFORE A COLD FRONT MOVES THROUGH MONDAY NIGHT. A MID-LEVEL SHORTWAVE RIDGE WILL MOVE ACROSS THE REGION BY MID-WEEK WHICH MAY RESULT IN A BREAK IN THE STORMY PATTERN...BUT THEN BY LATE WEEK THE MID/UPPER LEVEL PATTERNS TURNS SOUTHWESTERLY WITH A NUMBER OF DISTURBANCES ACROSS THE UPPER MIDWEST. SUNDAY NIGHT...EXPECT ONGOING STORMS ACROSS THE REGION...WITH THE BEST CHANCE FOR STORMS SOUTH OF HIGHWAY 2. GFS IS BY FAR THE MOST AGGRESSIVE WITH QPF BOTH THIS NIGHT AND THROUGH THE ENTIRE FORECAST PERIOD...THOUGH ALL GUIDANCE SUPPORTS FAIRLY GOOD INSTABILITY INTO SUNDAY NIGHT WHICH SHOULD RESULT IN SCATTERED TO NUMEROUS THUNDERSTORMS. A FEW COULD BE STRONG WITH 3000-4000 J/KG MUCAPE AVAILABLE EARLY IN THE EVENING. OTHERWISE A MILD NIGHT WITH LOWS IN THE LOW TO MID 60S. MONDAY INTO MONDAY NIGHT...WHEN THE FRONT MOVES THROUGH EXPECT ANOTHER ROUND OF SHOWERS AND STORMS...THOUGH INSTABILITY NOT AS IMPRESSIVE AS SUNDAY NIGHT. TUESDAY THROUGH FRIDAY...NOT AS WARM WITH CHANCES FOR SHOWERS AND STORMS MOST DAYS...WITH THE BEST CHANCE THURSDAY INTO THURSDAY NIGHT. HIGHS IN THE 70S...LOWS IN THE LOW TO MID 50S BY THE LAKE AND UPPER 50S TO LOW 60S INLAND. AS COOLER AND DRIER AIR MOVES IN FROM THE NORTHEAST DEW POINTS WILL FALL...RESULTING IN MUCH LESS HUMID CONDITIONS FOR THE LATTER PORTIONS OF THE WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1223 PM CDT SAT JUL 11 2015 VFR CONDITIONS EXPECTED TO PERSIST THROUGH MUCH OF THE AFTERNOON...WITH MVFR TO IFR CEILINGS AND VISIBILITY POSSIBLE AT ALL SITES OVERNIGHT TONIGHT. THIS AFTERNOON EXPECT WIDESPREAD VFR CLOUDS WITH A FEW SHOWERS AND MAYBE A THUNDERSTORM OR TWO. THIS EVENING...CHANCES FOR STORMS INCREASE...WITH BETTER CHANCES AT BRD/DLH/HYR. THEN LATE TONIGHT /AFTER MIDNIGHT/ EXPECT PATCHY FOG AND IFR CEILINGS TO DEVELOP...WITH A FEW SPOTS DEVELOPING LIFR CEILINGS. WINDS THROUGH THE PERIOD WILL BE GENERALLY LIGHT OUT OF THE SOUTH TO SOUTH-SOUTHEAST AT LESS THAN 10KTS...EXCEPT FOR A FEW GUSTS TO 15-20KT EARLY THIS AFTERNOON. && .PRELIMINARY POINT TEMPS/POPS... DLH 65 80 63 79 / 40 30 70 50 INL 62 85 64 83 / 10 40 40 50 BRD 65 89 65 87 / 50 30 70 40 HYR 65 83 66 82 / 30 40 60 50 ASX 62 82 63 80 / 10 30 60 50 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. LS...NONE. && $$ SHORT TERM...GSF LONG TERM...JJM AVIATION...JJM
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
300 PM MDT SAT JUL 11 2015 .SYNOPSIS... ANOTHER ROBUST ROUND OF THUNDERSTORMS UNDERWAY THIS AFTERNOON... FAVORING WESTERN PORTIONS OF THE AREA AS HIGH PRESSURE IN THE MID AND UPPER LEVELS OF THE ATMOSPHERE STRENGTHENS OVER EASTERN PORTIONS AND SHUTS DOWN CHANCES THERE. A WARMING TREND IS UNDERWAY FOR MUCH OF THE AREA AND WILL SEND HIGH TEMPERATURES ABOVE NORMAL ACROSS EASTERN NEW MEXICO BY TOMORROW...AND HOLD AT OR ABOVE NORMAL THROUGH THE UPCOMING WORK WEEK. THUNDERSTORMS WILL FAVOR CENTRAL AND WESTERN NEW MEXICO THROUGH MONDAY...THEN SHIFT TO INCLUDE NORTHERN PORTIONS OF THE AREA ON TUESDAY AND WEDNESDAY. ONLY THE EAST CENTRAL AND SOUTHEAST PLAINS LOOK TO MISS OUT ON RAIN OVER THE NEXT SEVEN DAYS. && .DISCUSSION... A MONSOON MOISTURE-RICH ATMOSPHERE PERSIST ACROSS OUR AREA WITH ABOVE NORMAL PWATS. TODAY`S ROUND OF STORMS FAVORS WESTERN PORTIONS OF OUR AREA...WHERE SHEAR IS ALLOWING FOR STRONG SUSTAINED UPDRAFTS AND A FEW SEVERE STORMS. WILL BE INTERESTING TO SEE IF THE CURRENT CROP OF STORMS CAN MAKE IT ACROSS THE RIO GRANDE VALLEY AND IMPACT THE I-25 CORRIDOR BETWEEN SOCORRO... BELEN AND ALBUQUERQUE. THE 19Z HRRR SHOWS THIS POTENTIAL SCENARIO BETWEEN 23-01Z. LOOKING MORE LIKE A GOOD BET HERE IN THE ALBUQUERQUE METRO WITH A LAST LOOK AT THE LATEST RADAR TRENDS AT 3 PM MDT. SUNDAY LOOKS TO BE DIFFERENT THAN TODAY AS THE UPPER HIGH... CURRENTLY OVER EAST TEXAS AND LOUISIANA...BUILDS WESTWARD TOWARD EASTERN NEW MEXICO AND WEST TEXAS. THIS INCREASE IN PRESSURE HEIGHTS WILL CORRESPOND WITH INCREASING HIGH TEMPERATURES... MAINLY EAST...AND A FOCUSING OF STORMS ACROSS WESTERN NEW MEXICO AND EASTERN ARIZONA. SHEAR...BOTH SPEED AND DIRECTIONAL...WILL BE CONSIDERABLY LESS SUNDAY COMPARED TO TODAY WITH THE UPPER HIGH MOVING-IN. SO...EXPECT A FEW ISOLATED STRONG STORMS WITH SLOWER MOTION TO TILT THE THREAT TOWARD LOCALLY HEAVY RAINFALL WITH MUCH LESS POTENTIAL FOR SEVERE. PRESSURE HEIGHTS TREND BACK DOWN MON/TUE AS THE UPPER HIGH BACKS OFF TO THE EAST A BIT...ALLOWING THE MONSOON MOISTURE PLUME TO TILT BACK OVER CENTRAL AND NORTHERN PORTIONS OF OUR CWFA... LEAVING-OUT ONLY THE SOUTHEAST IN TERMS OF RAIN CHANCES. A FAIRLY TYPICAL MONSOON PATTERN TO THEN PERSIST THROUGH THE END OF THE WORK-WEEK...ALTHOUGH NOT THE IDEAL PLUME POSITIONING WITH DEEP SOUTHERLY FLOW. OUR FORECAST TRENDS TOWARD CLIMO FOR FRI/SAT. 11 && .FIRE WEATHER... WETTING RAIN IN THE FORM OF SHOWERS AND THUNDERSTORMS WILL CONTINUE TODAY THROUGH MONDAY...ESPECIALLY WESTERN AND CENTRAL ZONES...THOUGH COVERAGE IS EXPECTED TO DOWN TREND. FOR THE REMAINDER OF THE WORK WEEK...RECYCLING OF MOISTURE WILL SUPPORT SHOWERS AND THUNDERSTORMS OVER THE HIGHER TERRAIN AND NORTH...WITH LESS ACTIVITY EAST CENTRAL ZONES. TEMPERATURES TO WARM A BIT...FINALLY REACHING ABOVE AVERAGE LEVELS ACROSS THE EAST ON SUNDAY...WHILE REMAINING BELOW AVERAGE ACROSS THE WEST. HAINES VALUES ARE FORECAST TO INCREASE...WITH AREAS OF 5 TUESDAY THROUGH FRIDAY MAINLY ACROSS THE NORTH. VENTILATION TO GENERALLY RANGE FROM GOOD TO EXCELLENT THROUGH THE FORECAST PERIOD...WITH AREAS OF POOR TO FAIR ACROSS WEST CENTRAL ZONES ON SUNDAY AND MONDAY AND ACROSS SOUTHWEST AND SOUTH CENTRAL ZONES THURSDAY AND FRIDAY. A BROAD UPPER LEVEL TROUGH REMAINS OVER THE WEST COAST WITH AN UNSEASONABLY STRONG JET STRETCHED FROM SOUTHERN CALIFORNIA TO THE GREAT PLAINS. UPPER LEVEL HIGH PRESSURE OVER THE SOUTHEAST STATE CONTINUES TO GRADUALLY STRENGTHEN AND SHIFT TO THE WEST WITH THE CENTER CURRENTLY POSITIONED OVER EAST TEXAS. THIS PATTERN IS SUPPORTING A FAIRLY ROBUST MONSOON SURGE FROM MEXICO INTO NEW MEXICO. THUNDERSTORMS THIS AFTERNOON HAVE FAVORED THE WEST. RH RECOVERIES TODAY WILL BE GOOD TO EXCELLENT ALL ZONES. AS THE UPPER CONTINUES TO SHIFT TO THE WEST...THE PLUME WILL BE NUDGED TO THE WEST AS WELL SUCH THAT DRIER CONDITIONS MOVE INTO THE EASTERN PLAINS WHILE THE WEST WILL SEE CONTINUED CONVECTIVE WETTING RAIN MAINLY OVER THE HIGHER TERRAIN. A WEAK WIND SHIFT INTO THE NORTHEAST COULD BE A FOCUS FOR SOME PRECIPITATION THERE ON MONDAY AND AN UPPER LEVEL DISTURBANCE JUST NORTH OF THE STATE ON TUESDAY COULD ALSO HELP EXTEND THE CHANCES OF WETTING RAIN ACROSS THE NORTH AND NORTHEAST. EXTENDED MODELS INDICATE THAT THE UPPER HIGH COULD WEAKEN/FLATTEN MID TO LATE WEEK AS SOME ENERGY EJECTS OUT OF THE WESTERN TROUGH AND OVER THE ROCKIES. THE MONSOON PLUME COULD REPOSITION OVER NEW MEXICO...THOUGH MOISTURE LOOKS SOMEWHAT LIMITED AT THIS TIME. 05 && .AVIATION... 18Z TAF CYCLE AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS TO INITIALLY FAVOR THE WESTERN HIGHER TERRAIN WITH A STEERING FLOW TO THE NORTHEAST AROUND 20KT. COVERAGE TO INCREASE THROUGH THE AFTERNOON INTO CENTRAL AND EASTERN ZONES. THE STRONGEST CELLS WILL PRODUCE LOCAL HEAVY RAIN WITH MVFR CIGS AND VISIBILITIES AND OCCASIONAL MOUNTAIN OBSCURATIONS. OVERNIGHT...SOME LINGERING RAIN SHOWERS ARE MOST LIKELY ACROSS THE NORTH. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS TO START DEVELOPING BEFORE NOON ON SUNDAY... ESPECIALLY OVER THE WESTERN AND SOUTHCENTRAL HIGHER TERRAIN. 05 && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 57 87 59 86 / 20 20 20 30 DULCE........................... 48 81 51 81 / 20 20 30 30 CUBA............................ 49 81 51 80 / 50 40 30 40 GALLUP.......................... 52 83 54 83 / 30 30 30 30 EL MORRO........................ 51 81 51 80 / 40 40 30 50 GRANTS.......................... 54 82 53 83 / 30 30 30 40 QUEMADO......................... 54 81 55 81 / 40 30 30 40 GLENWOOD........................ 56 87 56 87 / 30 40 30 50 CHAMA........................... 45 78 48 78 / 30 50 40 50 LOS ALAMOS...................... 56 83 59 84 / 50 50 40 50 PECOS........................... 53 83 56 83 / 30 20 30 30 CERRO/QUESTA.................... 48 80 51 80 / 30 50 40 40 RED RIVER....................... 44 69 45 69 / 50 50 50 50 ANGEL FIRE...................... 48 71 49 71 / 50 50 50 50 TAOS............................ 48 84 52 84 / 10 20 20 30 MORA............................ 52 79 53 79 / 50 40 40 50 ESPANOLA........................ 53 87 57 87 / 30 20 30 30 SANTA FE........................ 57 84 59 85 / 20 20 20 20 SANTA FE AIRPORT................ 54 86 57 87 / 20 20 30 20 ALBUQUERQUE FOOTHILLS........... 62 88 65 89 / 30 20 20 20 ALBUQUERQUE HEIGHTS............. 63 89 66 90 / 20 20 20 10 ALBUQUERQUE VALLEY.............. 61 91 63 92 / 20 20 20 10 ALBUQUERQUE WEST MESA........... 62 90 65 90 / 20 20 20 20 LOS LUNAS....................... 62 90 63 91 / 20 20 20 20 RIO RANCHO...................... 61 89 64 90 / 20 20 20 20 SOCORRO......................... 62 92 64 93 / 20 20 20 20 SANDIA PARK/CEDAR CREST......... 56 83 58 84 / 40 20 30 20 TIJERAS......................... 55 86 57 87 / 40 20 20 20 MORIARTY/ESTANCIA............... 52 86 53 87 / 20 20 20 10 CLINES CORNERS.................. 55 84 57 84 / 20 20 20 10 GRAN QUIVIRA.................... 57 84 58 86 / 30 20 20 20 CARRIZOZO....................... 61 88 62 90 / 20 20 10 10 RUIDOSO......................... 56 79 58 83 / 30 30 10 20 CAPULIN......................... 56 85 58 85 / 10 20 20 30 RATON........................... 52 88 56 88 / 10 10 20 10 SPRINGER........................ 54 89 57 89 / 5 10 20 10 LAS VEGAS....................... 54 84 55 85 / 10 10 20 10 CLAYTON......................... 61 96 65 95 / 5 5 20 10 ROY............................. 61 90 61 91 / 5 5 10 5 CONCHAS......................... 65 96 66 98 / 5 5 10 5 SANTA ROSA...................... 65 95 66 96 / 5 5 10 5 TUCUMCARI....................... 68 98 69 99 / 5 5 10 5 CLOVIS.......................... 65 93 65 96 / 10 5 5 5 PORTALES........................ 66 94 67 97 / 10 5 5 5 FORT SUMNER..................... 66 94 66 97 / 5 5 10 5 ROSWELL......................... 68 97 67 100 / 10 5 5 5 PICACHO......................... 61 89 62 92 / 10 10 10 10 ELK............................. 59 85 59 88 / 10 20 10 20 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 11
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
347 PM EDT SAT JUL 11 2015 .SYNOPSIS... A RIDGE OF HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT WILL CONTINUE TO PROVIDE THE NORTH COUNTRY WITH ABOVE NORMAL TEMPERATURES AND MAINLY DRY CONDITIONS THROUGH EARLY MONDAY. A FEW ISOLATED SHOWERS ARE POSSIBLE TONIGHT ACROSS NORTHERN VERMONT AND AGAIN ON SUNDAY AND MONDAY AFTERNOONS. A COLD FRONT WILL PROVIDE BETTER CHANCES FOR SHOWERS ON TUESDAY INTO WEDNESDAY...ALONG WITH COOLER TEMPERATURES. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... AS OF 330 PM EDT SATURDAY...BIG PICTURE ON WATER VAPOR SHOWS NW FLW ALOFT WITH BUILDING MID/UPPER LVL RIDGE ACROSS THE OHIO VALLEY/CENTRAL GREAT LAKES. HAVE NOTED A VERY WEAK 5H VORT WITH SOME MID LVL MOISTURE NEAR MANIWAKI, QC...WITH GENERAL SOUTHEAST MOVEMENT TWD OUR NORTHERN CWA BY TONIGHT. THE LATEST GFS AND HRRR MODELS SHOW VERY WEAK QPF OUTPUT FROM THIS FEATURE...WITH GREATEST CHCS OF A SHOWER ACROSS NEK OF VT. WL CONTINUE WITH PREVIOUS FCSTER THINKING A MENTION SCHC TO VERY LOW CHC POPS ACROSS OUR NORTHERN CWA TONIGHT. ANY QPF WL BE LIGHT <0.10". EXPECTING LOWS MAINLY IN THE 60S WITH 50S IN THE COOLER MTN VALLEYS. HAVE NOTED SFC DWPTS 3 TO 5 DEGREES WARMER THAN YESTERDAY AT THIS TIME...BUT WITH SOME BL WINDS BTWN 10 AND 15 KNOTS AND NO RAIN IN THE PAST 30 HOURS...WL NOT MENTION FOG IN FCST AT THIS TIME. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... AS OF 330 PM EDT SATURDAY...MID/UPPER LVL RIDGE BUILDS ACROSS OUR CWA ON SUNDAY WITH WARMING TEMPS AND SUBSIDENCE ALOFT. HOWEVER...ANOTHER VERY WEAK 5H VORT ALONG WITH STRONG SFC HEATING HELPING TO CREATE SOME INSTABILITY MAY PRODUCE A FEW MORE SHOWERS ON SUNDAY AFTN. HAVING DIFFICULTIES SEEING MUCH AREAL COVERAGE OR INTENSITY TO SHOWERS OR STORMS...GIVEN DRY AIR ALOFT AND PROGGED 500MB TEMPS NEAR -10C. IN ADDITION...SOUNDINGS ARE NOT VERY IMPRESSIVE WITH INSTABILITY PARAMETERS GIVEN WARM TEMPS ALOFT. SO WILL MENTION JUST ISOLATED CHCS ATTM FOR SUNDAY. GFS QPF FIELDS SEEM OVERDONE GIVEN POSITION OF RIDGE AXIS DIRECTLY OVERHEAD AND ASSOCIATED SUBSIDENCE. PROGGED 85H TEMPS WARM ANOTHER DEGREE FROM SATURDAY...AND WILL SUPPORT HIGHS IN THE LOWER 80S MTN VALLEY TOWNS TO M/UPPER 80S CHAMPLAIN AND SAINT LAWRENCE VALLEYS. FORECAST CHALLENGE ON MONDAY WILL BE CHANCES FOR ADDITIONS SHOWERS AND STORMS ASSOCIATED WITH S/W ENERGY UNDERCUTTING MID/UPPER LVL RIDGE. GFS CONTS TO BE THE MOST AGGRESSIVE WITH S/W ENERGY WHICH IS CURRENTLY OVER IOWA AND PRODUCING AREAS OF QPF ACROSS OUR CWA ON MONDAY AFTN. INSTABILITY PARAMETERS ARE MODEST WITH CAPE VALUES BETWEEN 400 AND 800 J/KG AND LIS BTWN -2C AND -4C OFF THE GFS...WHILE THE NAM SHOWS GREATER SFC BASED CAPE VALUES BTWN 1800 AND 2400 J/KG AND LIS NEAR -6C. THINKING THESE NUMBERS ARE OVERDONE DUE TO PROGGED SFC DWPTS TEMPS OF 20C OFF THE NAM SOLUTION. NAM/BTV 4KM INDICATES A WEAK SFC CONVERGENCE BOUNDARY FROM SE FLOW AROUND SFC HIGH PRES AND DEVELOPING SOUTHWEST FLW AHEAD OF NEXT SFC COLD FRNT ACROSS OUR CWA ON MONDAY...WHICH COULD PROVIDE ENOUGH LLVL FORCING TO PRODUCE SHOWERS/STORMS. WILL CONT TO MENTION SCHC TO LOW CHC POPS ON MONDAY AFTN/EVENING...BUT THINKING DRY AIR ALOFT AND WARM TEMPS ALOFT WILL LIMIT AREAL COVERAGE/INTENSITY OF SHOWERS/STORMS. PROGGED 85H TEMPS NEAR 18C ON MONDAY SUPPORT HIGHS MID/UPPER 80S WITH A FEW READINGS NEAR 90F IN THE WARMER VALLEYS. IN ADDITION...SFC DWPTS WILL CONT TO CLIMB SEVERAL DEGREES...ADDING TO THE HUMIDITY LEVELS. && .LONG TERM /TUESDAY THROUGH SATURDAY/... AS OF 424 AM EDT SATURDAY...FAIRLY ACTIVE WEATHER THROUGH WEDNESDAY WITH CHANCE OF SHOWERS AND PERHAPS A FEW THUNDERSTORMS. UPPER LEVEL TROUGH DEVELOPS OVER THE NORTHEAST ON TUESDAY. A SLOW MOVING COLD FRONT WILL DEPRESS SOUTH THROUGH THE REGION TUESDAY NIGHT INTO WEDNESDAY. SOME RATHER SIGNIFICANT DIFFERENCES BETWEEN GFS AND ECMWF REGARDING AMOUNT OF MOISTURE AVAILABLE AND POSITION OF SHORTWAVE MOVING THROUGH THE UPPER TROUGH DURING THIS PERIOD. ECMWF THE DRIER OF THE TWO MODELS WITH SHORTWAVE ENERGY PASSING FURTHER SOUTH. HAVE GONE CLOSE TO A BLEND OF THE TWO...KEEPING CHANCE SHOWERS WITH SLIGHT CHANCE OF STORMS TUESDAY INTO WEDNESDAY. GFS WOULD SUGGEST POTENTIAL OF LOCALLY HEAVY RAIN WITH PRECIPITABLE WATER VALUES 1.5 TO 1.8 INCHES...BUT LACK OF FORCING ON ECMWF MAY PRECLUDE ANY WIDESPREAD PRECIPITATION. DRIER WEATHER RETURNS LATER IN THE WEEK. CHANCES FOR SHOWERS DECREASE LATER WEDNESDAY INTO WEDNESDAY NIGHT AS FRONT DEPRESSES SOUTH OF THE AREA. UPPER TROUGH DEPARTS BY THURSDAY AND SURFACE FRONT PUSHES FURTHER SOUTH BEFORE STALLING OUT. THIS ALLOWS FOR HIGH PRESSURE AND MAINLY DRY CONDITIONS FOR THURSDAY AND FRIDAY. DISTURBANCE IN FLOW ALOFT COMBINED WITH WARM AIR ADVECTION WILL BRING CHANCE OF SHOWERS AND STORMS NEXT SATURDAY. TEMPERATURES WILL BE AROUND NORMAL ON TUESDAY...THEN FALL TO A BIT BELOW NORMAL WEDNESDAY AND THURSDAY WHEN HIGHS WILL BE IN THE UPPER 70S. SIGNIFICANT WARMING TREND POSSIBLE AS WE HEAD INTO NEXT WEEKEND. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... THROUGH 18Z SUNDAY...MAINLY VFR THROUGH THE PERIOD AS A RIDGE OF HIGH PRESSURE WILL BE OVER THE REGION. BROKEN DECK OF MID CLOUDS TONIGHT AS WEAK BOUNDARY DROPS INTO THE AREA. COULD BE AN ISOLATED SHOWER NORTH...BUT CHANCES TOO LOW FOR ANY INCLUSION IN TAFS AT THIS TIME. COULD ALSO BE SOME VISIBILITY RESTRICTIONS OVERNIGHT IN LIGHT FOG OR MIST...MAINLY AT MPV/SLK. BUT GIVEN EXPECTED MID CLOUD DECK...HAVE CONTINUED WITH PREVIOUS THINKING AND KEPT OUT ANY MENTION OF FOG. WINDS WILL BE SOUTH TO SOUTHWEST 5-10 KNOTS THIS AFTERNOON WITH SOME HIGHER GUSTS AT MSS. WINDS LIGHT AND VARIABLE TONIGHT AND SOUTHWEST LESS THAN 10 KNOTS ON SUNDAY. OUTLOOK 18Z SUNDAY THROUGH THURSDAY... 18Z SUN-12Z MON...MAINLY VFR EXCEPT FOR EARLY MORNING MVFR/IFR IN FOG MONDAY...MAINLY MPV/SLK. ISOLATED SHOWERS SUNDAY AFTERNOON. 12Z MON-00Z THU...SCATTERED TO NUMEROUS SHOWERS EACH DAY WITH MVFR CONDITIONS AT TIMES. ISOLATED THUNDER. 00Z THU-00Z FRI...MAINLY VFR. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...TABER NEAR TERM...TABER SHORT TERM...TABER LONG TERM...RJS AVIATION...RJS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
328 PM EDT SAT JUL 11 2015 .SYNOPSIS... A RIDGE OF HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT WILL CONTINUE TO PROVIDE THE NORTH COUNTRY WITH ABOVE NORMAL TEMPERATURES AND MAINLY DRY CONDITIONS THROUGH EARLY MONDAY. A FEW ISOLATED SHOWERS ARE POSSIBLE TONIGHT ACROSS NORTHERN VERMONT AND AGAIN ON SUNDAY AND MONDAY AFTERNOONS. A COLD FRONT WILL PROVIDE BETTER CHANCES FOR SHOWERS ON TUESDAY INTO WEDNESDAY...ALONG WITH COOLER TEMPERATURES. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... AS OF 330 PM EDT SATURDAY...BIG PICTURE ON WATER VAPOR SHOWS NW FLW ALOFT WITH BUILDING MID/UPPER LVL RIDGE ACROSS THE OHIO VALLEY/CENTRAL GREAT LAKES. HAVE NOTED A VERY WEAK 5H VORT WITH SOME MID LVL MOISTURE NEAR MANIWAKI, QC...WITH GENERAL SOUTHEAST MOVEMENT TWD OUR NORTHERN CWA BY TONIGHT. THE LATEST GFS AND HRRR MODELS SHOW VERY WEAK QPF OUTPUT FROM THIS FEATURE...WITH GREATEST CHCS OF A SHOWER ACROSS NEK OF VT. WL CONTINUE WITH PREVIOUS FCSTER THINKING A MENTION SCHC TO VERY LOW CHC POPS ACROSS OUR NORTHERN CWA TONIGHT. ANY QPF WL BE LIGHT <0.10". EXPECTING LOWS MAINLY IN THE 60S WITH 50S IN THE COOLER MTN VALLEYS. HAVE NOTED SFC DWPTS 3 TO 5 DEGREES WARMER THAN YESTERDAY AT THIS TIME...BUT WITH SOME BL WINDS BTWN 10 AND 15 KNOTS AND NO RAIN IN THE PAST 30 HOURS...WL NOT MENTION FOG IN FCST AT THIS TIME. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... AS OF 330 PM EDT SATURDAY...MID/UPPER LVL RIDGE BUILDS ACROSS OUR CWA ON SUNDAY WITH WARMING TEMPS AND SUBSIDENCE ALOFT. HOWEVER...ANOTHER VERY WEAK 5H VORT ALONG WITH STRONG SFC HEATING HELPING TO CREATE SOME INSTABILITY MAY PRODUCE A FEW MORE SHOWERS ON SUNDAY AFTN. HAVING DIFFICULTIES SEEING MUCH AREAL COVERAGE OR INTENSITY TO SHOWERS OR STORMS...GIVEN DRY AIR ALOFT AND PROGGED 500MB TEMPS NEAR -10C. IN ADDITION...SOUNDINGS ARE NOT VERY IMPRESSIVE WITH INSTABILITY PARAMETERS GIVEN WARM TEMPS ALOFT. SO WILL MENTION JUST ISOLATED CHCS ATTM FOR SUNDAY. GFS QPF FIELDS SEEM OVERDONE GIVEN POSITION OF RIDGE AXIS DIRECTLY OVERHEAD AND ASSOCIATED SUBSIDENCE. PROGGED 85H TEMPS WARM ANOTHER DEGREE FROM SATURDAY...AND WILL SUPPORT HIGHS IN THE LOWER 80S MTN VALLEY TOWNS TO M/UPPER 80S CHAMPLAIN AND SAINT LAWRENCE VALLEYS. FORECAST CHALLENGE ON MONDAY WILL BE CHANCES FOR ADDITIONS SHOWERS AND STORMS ASSOCIATED WITH S/W ENERGY UNDERCUTTING MID/UPPER LVL RIDGE. GFS CONTS TO BE THE MOST AGGRESSIVE WITH S/W ENERGY WHICH IS CURRENTLY OVER IOWA AND PRODUCING AREAS OF QPF ACROSS OUR CWA ON MONDAY AFTN. INSTABILITY PARAMETERS ARE MODEST WITH CAPE VALUES BETWEEN 400 AND 800 J/KG AND LIS BTWN -2C AND -4C OFF THE GFS...WHILE THE NAM SHOWS GREATER SFC BASED CAPE VALUES BTWN 1800 AND 2400 J/KG AND LIS NEAR -6C. THINKING THESE NUMBERS ARE OVERDONE DUE TO PROGGED SFC DWPTS TEMPS OF 20C OFF THE NAM SOLUTION. NAM/BTV 4KM INDICATES A WEAK SFC CONVERGENCE BOUNDARY FROM SE FLOW AROUND SFC HIGH PRES AND DEVELOPING SOUTHWEST FLW AHEAD OF NEXT SFC COLD FRNT ACROSS OUR CWA ON MONDAY...WHICH COULD PROVIDE ENOUGH LLVL FORCING TO PRODUCE SHOWERS/STORMS. WILL CONT TO MENTION SCHC TO LOW CHC POPS ON MONDAY AFTN/EVENING...BUT THINKING DRY AIR ALOFT AND WARM TEMPS ALOFT WILL LIMIT AREAL COVERAGE/INTENSITY OF SHOWERS/STORMS. PROGGED 85H TEMPS NEAR 18C ON MONDAY SUPPORT HIGHS MID/UPPER 80S WITH A FEW READINGS NEAR 90F IN THE WARMER VALLEYS. IN ADDITION...SFC DWPTS WILL CONT TO CLIMB SEVERAL DEGREES...ADDING TO THE HUMIDITY LEVELS. && .LONG TERM /TUESDAY THROUGH SATURDAY/... AS OF 424 AM EDT SATURDAY...RATHER UNSETTLED AT THE BEGINNING OF THE LONG TERM PERIOD FROM MONDAY NIGHT THROUGH WEDNESDAY...WITH A CHANCE FOR SHOWERS AND THUNDERSTORMS. A SLOW MOVING COLD FRONT WILL MOVE SLOWLY SOUTH THROUGH THE REGION TUESDAY NIGHT WITH SHOWERS LINGERING INTO WEDNESDAY. A RIDGE OF HIGH PRESSURE WILL BUILD SOUTHEAST FROM CANADA AND THE GREAT LAKES ON THURSDAY AND WILL REMAIN OVER THE REGION THROUGH FRIDAY...WITH FAIR AND DRY WEATHER EXPECTED THURSDAY AND FRIDAY. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... THROUGH 18Z SUNDAY...MAINLY VFR THROUGH THE PERIOD AS A RIDGE OF HIGH PRESSURE WILL BE OVER THE REGION. BROKEN DECK OF MID CLOUDS TONIGHT AS WEAK BOUNDARY DROPS INTO THE AREA. COULD BE AN ISOLATED SHOWER NORTH...BUT CHANCES TOO LOW FOR ANY INCLUSION IN TAFS AT THIS TIME. COULD ALSO BE SOME VISIBILITY RESTRICTIONS OVERNIGHT IN LIGHT FOG OR MIST...MAINLY AT MPV/SLK. BUT GIVEN EXPECTED MID CLOUD DECK...HAVE CONTINUED WITH PREVIOUS THINKING AND KEPT OUT ANY MENTION OF FOG. WINDS WILL BE SOUTH TO SOUTHWEST 5-10 KNOTS THIS AFTERNOON WITH SOME HIGHER GUSTS AT MSS. WINDS LIGHT AND VARIABLE TONIGHT AND SOUTHWEST LESS THAN 10 KNOTS ON SUNDAY. OUTLOOK 18Z SUNDAY THROUGH THURSDAY... 18Z SUN-12Z MON...MAINLY VFR EXCEPT FOR EARLY MORNING MVFR/IFR IN FOG MONDAY...MAINLY MPV/SLK. ISOLATED SHOWERS SUNDAY AFTERNOON. 12Z MON-00Z THU...SCATTERED TO NUMEROUS SHOWERS EACH DAY WITH MVFR CONDITIONS AT TIMES. ISOLATED THUNDER. 00Z THU-00Z FRI...MAINLY VFR. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...TABER NEAR TERM...TABER SHORT TERM...TABER LONG TERM...WGH AVIATION...RJS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
340 PM EDT SAT JUL 11 2015 .SYNOPSIS...A WEAK AREA OF LOW PRESSURE WILL DROP SOUTHEAST FROM VIRGINIA INTO EASTERN NORTH CAROLINA THIS AFTERNOON AND THEN MOVE OFFSHORE TONIGHT. THE TRAILING COLD FRONT WILL MOVE THROUGH THE AREA THIS EVENING AND TONIGHT. WEAK SURFACE HIGH PRESSURE WILL EXTEND INTO THE AREA ON SUNDAY. AN INCREASINGLY ACTIVE NORTHWEST FLOW ALOFT WILL DEVELOP DOWNSTREAM ACROSS THE CAROLINAS AND MID ATLANTIC EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 320 PM SATURDAY... A MID-LEVEL DISTURBANCE DIVING ACROSS SOUTHEAST VA HAS TRIGGERED NUMEROUS STORMS OVER NORTHEAST NC IN A STRONG INSTABILITY AXIS NORTHEAST OF A WEAK SURFACE LOW OVER THE COASTAL PLAIN. THE CONVECTION HAS BEEN MORE SCATTERED AND LESS INTENSE THE NORTHERN COASTAL PIEDMONT/COASTAL PLAIN....WITH REALLY JUST SHOWERS NORTH AND EAST OF THE TRIANGLE. THE CONVECTION WILL HAVE THE OPPORTUNITY TO INTENSIFY AS IT MOVES EAST OF I-95...BUT RADAR TRENDS AND RECENT HRRR RUNS SUGGEST THE DEEPEST CONVECTION WILL REMAIN EAST OF THE RAH CWA AND WITHIN THE ONGOING SEVERE TSTORM WATCH. TO THE SOUTH AND WEST...THE CU FIELD HAS BEEN EXPANDING BUT NO MORE THAN A STRAY SHOWER IS EXPECTED THROUGH THIS EVENING. TONIGHT...THE AFOREMENTIONED SURFACE LOW WILL DRIFT EAST OFFSHORE AND ALLOW A SECONDARY...EFFECTIVE FRONT TO OUR NORTH TO SLIP SOUTH THROUGH THE AREA. NORTH-NORTHEASTERLY WIND WILL ADVECT SOME LOW- LEVEL MOISTURE CURRENTLY OVER VA... WHERE CEILINGS ARE IN THE 1000- 2000FT RANGE...SOUTH ACROSS THE COASTAL PLAIN. SREF PROBABILITIES SHOW MORE POTENTIAL FOR STRATUS ACROSS THE CENTRAL PIEDMONT...BUT NAM/GFS AND RAP SOUNDINGS SHOW BETTER EAST OF US HWY 1. LOWS IN THE MID/UPPER 60S NORTH AND WEST TO LOWER SOUTH AND EAST 70S. && .SHORT TERM /SUNDAY AND SUNDAY NIGHT/... AS OF 340 PM SATURDAY... WITH THE COLD FRONT SETTLING ALONG THE SOUTHEAST COAST THE WEAK SURFACE LOW MEANDERING OFF THE NC/VA COAST...A SLIGHTLY COOLER AND DRIER NORTHERLY FLOW WILL PREVAIL DURING THE DAY. THICKNESSES AROUND 1400M SUNDAY MORNING ARE ABOUT 10M BELOW NORMAL AND HIGHS SHOULD BE A COUPLE DEGREES BELOW NORMAL IN THE 87-91 RANGE. A WEAK DISTURBANCE AND/OR OUTFLOW FROM UPSTREAM CONVECTION IS FORECAST TO CROSS THE MOUNTAINS SUNDAY EVENING...WHICH MAY TRIGGER SOME SOME SHOWERS LATE IN THE EVENING OR EVEN OVERNIGHT. HOWEVER...THE MAIN SHORTWAVE WILL PASS WELL TO OUR NORTH AND ITS STILL UNCERTAIN HOW MUCH LOW-LEVEL MOISTURE RECOVERY THERE WILL BE TO AID IN ANY ADDITIONAL MUCAPE OVERNIGHT. WILL INCLUDE A CHANCE POP WEST TO SLIGHT CHANCE POP EAST...FOLLOWING A GENERAL CONSENSUS OF GUIDANCE. LOWS IN THE UPPER 60S TO AROUND 70. && .LONG TERM /MONDAY THROUGH SATURDAY/... AS OF 310 PM SATURDAY... THE MID LEVEL RIDGE IS PROGGED TO BE SITUATED OVER TX/LA...WITH TROUGHS OVER EACH COAST...THROUGH THE MID TO END OF NEXT WEEK. THIS WILL RESULT IN NORTHWEST FLOW OVER THE REGION...LEADING TO POTENTIAL REMNANT MCS/MCVS TRACKING OVERHEAD AND HENCE SHOWERS/STORMS. THIS TYPE OF PATTERN IS HARD TO NAIL DOWN PRECISE TIMING/LOCATION OF ANY CONVECTION...WITH AT LEAST DIURNAL TYPE POPS EACH DAY. AS OF NOW... TUESDAY LOOKS TO BE THE BEST CHANCE OF SIGNIFICANT COVERAGE AS MODELS INDICATE A FAIRLY ROBUST SHORTWAVE DIGGING INTO THE AREA. IN ADDITION BETTER SEVERE WEATHER PARAMETERS ARE PROGGED OVER THE REGION DURING THIS TIME FRAME AS DEEP LAYER SHEAR ON THE ORDER OF 35 KNOTS IS EXPECTED AND MODELS INDICATE A MODIFIED EML ADVECTING INTO THE AREA. HOWEVER...CONFIDENCE IS STILL NOT VERY HIGH GIVEN THE FACT THAT THE ECMWF IS STILL 12-24 HOURS BEHIND IN RELATION TO THE ARRIVAL OF THE AFOREMENTIONED ROBUST SHORTWAVE. NEVERTHELESS...WILL SHOW THE RELATIVE HIGHEST POPS ON TUESDAY/WEDNESDAY FOR THIS PERIOD WITH AT LEAST CLIMO POPS FOR THE REMAINDER OF THE PERIOD. THE MID LEVEL FLOW SHOULD FLATTEN OUT SOME BY THE END OF THE WEEK AS THE MID LEVEL RIDGE STARTS TO EXPAND EASTWARD ONCE AGAIN. TEMPS SHOULD BE SLIGHTLY ABOVE NORMAL FOR MOST OF THE PERIOD...WITH HIGHS IN THE LOW/MID 90S AND LOWS IN THE LOW/MID 70S...BUT THIS COULD BE ALTERED BY HIGHER CLOUD/PRECIP COVERAGE. && .AVIATION /18Z SATURDAY THROUGH WEDNESDAY/... AS OF 210 PM SATURDAY... SCATTERED SHOWERS HAVE DEVELOP TO THE NORTH OF KRDU AND KRWI IN RESPONSE TO STRONG HEATING AND AN UPPER LEVEL DISTURBANCES MOVING NORTHWEST TO SOUTHEAST ACROSS THE AREA. EXPECT THESE SHOWERS TO INCREASE AND COVERAGE AND ALSO IN INTENSITY...WITH THE BEST CHANCE OF A THUNDERSTORM AT KRWI BETWEEN 18Z AND 21. MEANWHILE...WINDS WILL BE OUT OF THE NORTH-NORTHWEST THIS AFTERNOON...GUSTING TO 15- 18KT SPORADICALLY...THEN TURNING TO NORTHEASTERLY THIS EVENING AS A WAVE OF LOW PRESSURE MOVES FROM THE COASTAL PLAIN TOWARD THE OUTER BANKS AND A COLD FRONT SLIPS THROUGH THE AREA. THIS NORTHEASTERLY FLOW SHOULD ADVECT IN LOW-LEVEL MOISTURE AND CAUSE STRATUS TO FORM LATE TONIGHT...MAINLY EAST OF KRDU. SOME GUIDANCE INDICATES IFR STRATUS AND OTHERS INDICATE AS LOW AS LIFR. CONFIDENCE IN LIFR CONDITIONS ISN`T VERY HIGH AT THE MOMENT...BUT KRWI WOULD LIKELY HAVE THE BEST CHANCE OF THE POOREST CONDITIONS. DRIER AIR AND LESS INSTABILITY WILL LEAD TO FEW STORMS ON SUNDAY...IF ANY...AND VFR CONDITIONS. LOOKING AHEAD: PREDOMINATELY VFR CONDITIONS ARE EXPECTED UNTIL MONDAY...WHEN A SERIES OF DISTURBANCES APPROACHING FROM THE NORTHWEST WILL RESULT IN A PERIOD OF ACTIVE WEATHER THROUGH MIDWEEK. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BLAES NEAR TERM...22 SHORT TERM...22 LONG TERM...KRD AVIATION...22
AREA FORECAST DISCUSSION
NWS RALEIGH NC
320 PM EDT SAT JUL 11 2015 .SYNOPSIS...A WEAK AREA OF LOW PRESSURE WILL DROP SOUTHEAST FROM VIRGINIA INTO EASTERN NORTH CAROLINA THIS AFTERNOON AND THEN MOVE OFFSHORE TONIGHT. THE TRAILING COLD FRONT WILL MOVE THROUGH THE AREA THIS EVENING AND TONIGHT. WEAK SURFACE HIGH PRESSURE WILL EXTEND INTO THE AREA ON SUNDAY. AN INCREASINGLY ACTIVE NORTHWEST FLOW ALOFT WILL DEVELOP DOWNSTREAM ACROSS THE CAROLINAS AND MID ATLANTIC EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 320 PM SATURDAY... A MID-LEVEL DISTURBANCE DIVING ACROSS SOUTHEAST VA HAS TRIGGERED NUMEROUS STORMS OVER NORTHEAST NC IN A STRONG INSTABILITY AXIS NORTHEAST OF A WEAK SURFACE LOW OVER THE COASTAL PLAIN. THE CONVECTION HAS BEEN MORE SCATTERED AND LESS INTENSE THE NORTHERN COASTAL PIEDMONT/COASTAL PLAIN....WITH REALLY JUST SHOWERS NORTH AND EAST OF THE TRIANGLE. THE CONVECTION WILL HAVE THE OPPORTUNITY TO INTENSIFY AS IT MOVES EAST OF I-95...BUT RADAR TRENDS AND RECENT HRRR RUNS SUGGEST THE DEEPEST CONVECTION WILL REMAIN EAST OF THE RAH CWA AND WITHIN THE ONGOING SEVERE TSTORM WATCH. TO THE SOUTH AND WEST...THE CU FIELD HAS BEEN EXPANDING BUT NO MORE THAN A STRAY SHOWER IS EXPECTED THROUGH THIS EVENING. TONIGHT...THE AFOREMENTIONED SURFACE LOW WILL DRIFT EAST OFFSHORE AND ALLOW A SECONDARY...EFFECTIVE FRONT TO OUR NORTH TO SLIP SOUTH THROUGH THE AREA. NORTH-NORTHEASTERLY WIND WILL ADVECT SOME LOW- LEVEL MOISTURE CURRENTLY OVER VA... WHERE CEILINGS ARE IN THE 1000- 2000FT RANGE...SOUTH ACROSS THE COASTAL PLAIN. SREF PROBABILITIES SHOW MORE POTENTIAL FOR STRATUS ACROSS THE CENTRAL PIEDMONT...BUT NAM/GFS AND RAP SOUNDINGS SHOW BETTER EAST OF US HWY 1. LOWS IN THE MID/UPPER 60S NORTH AND WEST TO LOWER SOUTH AND EAST 70S. && .SHORT TERM /SUNDAY AND SUNDAY NIGHT/... AS OF 350 AM FRIDAY... SUNDAY INTO SUNDAY NIGHT: WITH THE WAVY FRONTAL ZONE DRAPED ALONG THE SOUTHEAST COAST...WEAK SURFACE RIDGING WITH A RESERVOIR OF LOW- LEVEL DRY/LOWER THETA-E AIR WILL BE IN PLACE ACROSS CENTRAL NC ON SUNDAY...WHICH WILL MAKE FOR COMFORTABLE HUMIDITY LEVELS BY JULY STANDARDS WITH SEASONABLE DAYTIME HIGHS IN THE UPPER 80S TO LOWER 90S. THE POTENTIAL WILL BE THERE FOR SOME ISOLATED SHOWERS ACROSS THE AREA ON SUNDAY AND EVEN SUNDAY NIGHT...ESPECIALLY ACROSS THE NW PIEDMONT AS FCST MODELS DIFFER WITH THE TIMING OF THE INDIVIDUAL WEAK SHORTWAVE DISTURBANCES EMBEDDED IN THE NWLY FLOW...ON THE NORTHEASTERN FLANKS OF THE STRONG MID-LEVEL ANTICYCLONE CENTERED ACROSS THE SOUTHERN PLAINS. THUNDER MAY BE HARD TO COME BY AS INSTABILITY IS LIMITED OWING TO THE LOW-LEVEL DRY AIR IN PLACE AND WARM TEMPERATURES ALOFT. LOWS IN THE MID 60S TO LOWER 70S. && .LONG TERM /MONDAY THROUGH SATURDAY/... AS OF 310 PM SATURDAY... THE MID LEVEL RIDGE IS PROGGED TO BE SITUATED OVER TX/LA...WITH TROUGHS OVER EACH COAST...THROUGH THE MID TO END OF NEXT WEEK. THIS WILL RESULT IN NORTHWEST FLOW OVER THE REGION...LEADING TO POTENTIAL REMNANT MCS/MCVS TRACKING OVERHEAD AND HENCE SHOWERS/STORMS. THIS TYPE OF PATTERN IS HARD TO NAIL DOWN PRECISE TIMING/LOCATION OF ANY CONVECTION...WITH AT LEAST DIURNAL TYPE POPS EACH DAY. AS OF NOW... TUESDAY LOOKS TO BE THE BEST CHANCE OF SIGNIFICANT COVERAGE AS MODELS INDICATE A FAIRLY ROBUST SHORTWAVE DIGGING INTO THE AREA. IN ADDITION BETTER SEVERE WEATHER PARAMETERS ARE PROGGED OVER THE REGION DURING THIS TIME FRAME AS DEEP LAYER SHEAR ON THE ORDER OF 35 KNOTS IS EXPECTED AND MODELS INDICATE A MODIFIED EML ADVECTING INTO THE AREA. HOWEVER...CONFIDENCE IS STILL NOT VERY HIGH GIVEN THE FACT THAT THE ECMWF IS STILL 12-24 HOURS BEHIND IN RELATION TO THE ARRIVAL OF THE AFOREMENTIONED ROBUST SHORTWAVE. NEVERTHELESS...WILL SHOW THE RELATIVE HIGHEST POPS ON TUESDAY/WEDNESDAY FOR THIS PERIOD WITH AT LEAST CLIMO POPS FOR THE REMAINDER OF THE PERIOD. THE MID LEVEL FLOW SHOULD FLATTEN OUT SOME BY THE END OF THE WEEK AS THE MID LEVEL RIDGE STARTS TO EXPAND EASTWARD ONCE AGAIN. TEMPS SHOULD BE SLIGHTLY ABOVE NORMAL FOR MOST OF THE PERIOD...WITH HIGHS IN THE LOW/MID 90S AND LOWS IN THE LOW/MID 70S...BUT THIS COULD BE ALTERED BY HIGHER CLOUD/PRECIP COVERAGE. && .AVIATION /18Z SATURDAY THROUGH WEDNESDAY/... AS OF 210 PM SATURDAY... SCATTERED SHOWERS HAVE DEVELOP TO THE NORTH OF KRDU AND KRWI IN RESPONSE TO STRONG HEATING AND AN UPPER LEVEL DISTURBANCES MOVING NORTHWEST TO SOUTHEAST ACROSS THE AREA. EXPECT THESE SHOWERS TO INCREASE AND COVERAGE AND ALSO IN INTENSITY...WITH THE BEST CHANCE OF A THUNDERSTORM AT KRWI BETWEEN 18Z AND 21. MEANWHILE...WINDS WILL BE OUT OF THE NORTH-NORTHWEST THIS AFTERNOON...GUSTING TO 15- 18KT SPORADICALLY...THEN TURNING TO NORTHEASTERLY THIS EVENING AS A WAVE OF LOW PRESSURE MOVES FROM THE COASTAL PLAIN TOWARD THE OUTER BANKS AND A COLD FRONT SLIPS THROUGH THE AREA. THIS NORTHEASTERLY FLOW SHOULD ADVECT IN LOW-LEVEL MOISTURE AND CAUSE STRATUS TO FORM LATE TONIGHT...MAINLY EAST OF KRDU. SOME GUIDANCE INDICATES IFR STRATUS AND OTHERS INDICATE AS LOW AS LIFR. CONFIDENCE IN LIFR CONDITIONS ISN`T VERY HIGH AT THE MOMENT...BUT KRWI WOULD LIKELY HAVE THE BEST CHANCE OF THE POOREST CONDITIONS. DRIER AIR AND LESS INSTABILITY WILL LEAD TO FEW STORMS ON SUNDAY...IF ANY...AND VFR CONDITIONS. LOOKING AHEAD: PREDOMINATELY VFR CONDITIONS ARE EXPECTED UNTIL MONDAY...WHEN A SERIES OF DISTURBANCES APPROACHING FROM THE NORTHWEST WILL RESULT IN A PERIOD OF ACTIVE WEATHER THROUGH MIDWEEK. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BLAES NEAR TERM...22 SHORT TERM...CBL LONG TERM...KRD AVIATION...22
AREA FORECAST DISCUSSION
NWS MEDFORD OR
222 PM PDT SAT JUL 11 2015 .DISCUSSION...TEMPERATURES ARE SIMILAR TO WHAT THEY WERE 24 HOURS AGO...WHICH ARE BELOW NORMAL FOR THIS TIME OF YEAR. A WELL-DEFINED TROUGH IS MOVING INTO THE COAST NOW...AND WILL BRING WITH IT THE CHANCE FOR SHOWERS AT THE COAST THROUGH THE EVENING...AND SHOULD PROVIDE ENOUGH ENERGY FOR SOME THUNDERSTORMS MAINLY EAST OF THE CASCADES THIS AFTERNOON. MAINLY GENERIC SHOWERS ARE OCCURRING NOW ALONG AND EAST OF THE CASCADES AND DON`T EXPECT MANY STORMS TODAY BECAUSE INSTABILITY IS MARGINAL FOR STORMS IN THE FIRST PLACE. THE LATEST HRRR OUTPUT REMAIN CONSISTENT WITH THIS IDEA. TONIGHT...THE INCOMING TROUGH WILL KEEP THE CHANCE FOR SHOWERS IN THE FORECAST AREA. TOMORROW IS TRENDING LESS UNSTABLE PER RECENT MODEL RUNS...THOUGH STILL A BIT MORE UNSTABLE THAN TODAY. WE HAVE KEPT CONFIDENCE WORDING IN THE FORECAST VERSUS COVERAGE...SIMPLY BECAUSE THE PATTERN AND THE PARAMETERS THAT SUPPORT THUNDERSTORMS ARE NOT VERY ROBUST TOMORROW AND THE HIGH RES NMM AND ARW MODELS ALIGN WITH THIS THINKING. SAID MORE SUCCINCTLY...CONFIDENCE IS NOT HIGH WE`LL HAVE MUCH THUNDERSTORM ACTIVITY TOMORROW. TEMPERATURES TOMORROW WILL AGAIN BE 5 TO 10 DEGREES BELOW NORMAL. ON MONDAY MIDLEVEL FLOW SWITCHES MORE WESTERLY AND THIS BRINGS IN DRIER AIR ALOFT...FURTHER REDUCING THE CHANCE FOR SHOWERS AND THUNDERSTORMS. TEMPERATURES MONDAY AND TUESDAY WILL REMAIN BELOW NORMAL UNDER PERSISTENT UPPER TROUGHING. WEDNESDAY INTO SATURDAY TEMPERATURES WILL GRADUALLY REBOUND AS THE UPPER TROUGH AXIS NUDGES EASTWARD SOME...WARMING TEMPERATURES A FEW DEGREES EACH DAY. MOSTLY DRY CONDITIONS ARE EXPECTED DURING THIS TIMEFRAME. FRIDAY AND SATURDAY BOTH THE EC AND GFS...WITH GOOD AGREEMENT AMONGST THE GFS ENSEMBLE MEMBERS...SHOW A HEFTY UPPER RIDGE BUILDING OVER THE NE PAC WATERS. THE EC PEGS IT AT 561 DM. THIS PLACES OUR FORECAST AREA TO THE EAST OF THE RIDGE IN A REGION OF NORTHERLY OR WESTERLY WINDS ALOFT...LIKELY KEEPING US DRY AND PREVENTING ANY HEATWAVES. THE EVOLUTION OF THIS RIDGE WILL LIKELY DICTATE OUR WEATHER OUT PAST DAY 7. OF NOTE ARE SOME TROPICAL CYCLONES IN THE WEST PACIFIC THAT WILL ALSO LIKELY PLAY A ROLE IN OUR EVOLVING WEATHER PATTERN IN THE EXTENDED...AND MAY WREAK HAVOC ON MODEL CONSISTENCY IN THE NEXT FEW DAYS. && .AVIATION...FOR THE 11/18Z TAF CYCLE...ALONG THE COAST AND IN THE UMPQUA BASIN...MVFR CIGS HAVE CLEARED TO VFR. THE LOWER CONDITIONS WILL MOVE BACK ONSHORE THIS EVENING. OVER THE REMAINDER OF THE AREA...VFR CONDITIONS WILL PREVAIL...BUT THERE WILL BE ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS WITH LOCAL OBSCURATION OF HIGHER TERRAIN. WEST WINDS WILL BE A FEW MPH STRONGER DUE TO INCREASING ONSHORE PRESSURE GRADIENT. /FB && .MARINE...UPDATED 200 PM PDT SATURDAY 11 JULY 2015...LIGHT SOUTH WINDS WILL PERSIST THROUGH TONIGHT AS A WEAK FRONT PASSES OVER THE WATERS THIS EVENING. THERE WILL BE SOME LIGHT RAIN WITH THIS FRONTAL PASSAGE BUT WINDS WILL REMAIN LIGHT. WINDS WILL GRADUALLY TURN NORTHERLY SUNDAY INTO MONDAY. A THERMAL TROUGH WILL DEVELOP AND STRENGTHEN MONDAY NIGHT INTO TUESDAY. THIS WILL INCREASE WINDS AND SEAS WILL BECOME CHOPPY AND WIND-DRIVEN. WINDS MAY INCREASE TO GALE FORCE BY WEDNESDAY AFTERNOON OFFSHORE AND SOUTH OF CAPE BLANCO. SMALL CRAFT ADVISORY WINDS AND SEAS WILL DEVELOP OVER THE SOUTHERN OUTER WATERS TUESDAY...SPREADING TO THE REST OF THE AREA BY WEDNESDAY. -MND && .FIRE WEATHER...UPDATED 300 PM PDT SATURDAY 11 JULY 2015...WITH WESTERLY FLOW MOVING INTO THE FORECAST AREA BEHIND THE TROUGH..THE MOIST AIR MASS WILL BE DISPLACED BY COOLER BUT MUCH DRIER AIR. AFTERNOON HUMIDITY WILL BE ABOUT 15-20 PERCENT LOWER THAN YESTERDAY. THE EXCEPTION IS ALONG THE COAST AND THE VALLEYS AND LOWER SLOPES OF THE UMPQUA BASIN WHERE LOW LEVEL MARINE AIR IS ENTRENCHED. A TROUGH MOVING ACROSS SOUTHERN OREGON SUNDAY WILL PROVIDE TRIGGERS FOR THUNDERSTORMS FROM THE CASCADES EASTWARD. THE MOST UNSTABLE AREA WILL BE IN THE CASCADES FROM CRATER LAKE NORTH WHERE FORECAST SOUNDING INDICATES LIFTED INDEX OF -3 IS POSSIBLE. OUTSIDE THIS AREA IN KLAMATH AND LAKE COUNTIES..THERE APPEARS TO BE A MID LEVEL CAPPING AND LIFTING OF THE PARCEL FROM THE CLOUD BASE ONLY GIVES MARGINAL INSTABILITY. BY WEDNESDAY NIGHT AND EARLY THURSDAY..A THERMAL TROUGH WILL EXPAND NORTH INTO THE COASTAL ZONES SOUTHERN OREGON LASTING THROUGH SATURDAY. EXPECT LOWERING NIGHT TIME HUMIDITY RECOVERY IN THE SECOND HALF OF NEXT WEEK. /FB && .MFR WATCHES/WARNINGS/ADVISORIES... OR...NONE. CA...NONE. PACIFIC COASTAL WATERS...NONE. $$ NSK/NSK/FJB
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
324 PM CDT SAT JUL 11 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 324 PM CDT SAT JUL 11 2015 LOW CONFIDENCE ON CONVECTION FOR THE AFTERNOON/EVENING. 700MB READINGS ARE IN THE +8 TO +11C RANGE...WITH WARMEST READINGS OVERTOP THE DRY LINE BETWEEN KPIR/KMBG. TEMPERATURES ARE IN THE UPPER 80S...AND DEWPOINTS ARE APPROACHING 70F...ENOUGH TO GENERATE OVER 4000 J/KG MLCAPE. WINDS THROUGH THE PROFILES ARE RELATIVELY WEAK WITH SOME DIRECTIONAL SHEAR. THESE INGREDIENTS ARE ENOUGH TO WARRANT AN SPC SLIGHT RISK OUTLOOK FOR MUCH OF THE CWA. POOR OVERALL CONFIDENCE STEMS FORM THE LACK OF ANY UPPER WAVE...AND A LACK OF CONVECTION BEING GENERATED IN HIGH RES GUIDANCE WITH ONLY THE MOST RECENT ITERATIONS OF THE HRRR DEPICTING ANY STORMS. BEST ENVIRONMENT MAY BE AHEAD OF THE MID LEVEL WARM ADVECTION IN FAR NORTHEAST COUNTIES...BUT ALSO ALONG THE SURFACE TROF IF WE CAN BREAK THE CAP...WITH BISMARCK 18Z SOUNDING INDICATING A CONVECTIVE TEMPERATURE IN THE LOW 90S. A MORE DISCERNIBLE WAVE IS EVIDENT FOR SUNDAY. THE DRY LINE WILL ALSO BE PUSHED INTO THE JAMES VALLEY...SO TEMPERATURES COULD MAX OUT IN THE UPPER 90S WITH A FEW SPOTS AROUND 100. WILL LEAVE HEAT ADVISORY HEADLINE IN PLACE. NORTHWEST FLOW FOLLOWS FOR MONDAY...WITH HIGH PRESSURE TO THE WEST. THE RESULT WILL BE A DECENT FETCH OUT OF THE CANADIAN WILDFIRE REGION AND MORE SMOKE IN THE AREA. TEMPERATURES WILL BE A TAD COOLER BUT STILL A FEW DEGREES ABOVE AVERAGE THANKS TO WEAK COLD ADVECTION. CANT RULE OUT AN ISOLATED HEAT OF THE AFTERNOON STORM MONDAY THANKS TO STEEP LOW/MID LEVEL LAPSE RATES. .LONG TERM...(TUESDAY THROUGH SATURDAY) ISSUED AT 324 PM CDT SAT JUL 11 2015 THE LATEST LONG TERM MODELS CONTINUE TO INDICATE A FAIRLY ACTIVE PATTERN ACROSS THE REGION THROUGH THE PERIOD. MID LEVEL RIDGING EARLY IN THE PERIOD WILL GIVE WAY TO FALLING HEIGHTS AND PLENTY OF S/W ENERGY AS A DECENT JET DIGS A TROF INTO THE NORTHWEST CONUS. THE TROF IS EXPECTED TO TRACK ACROSS THE NORTHERN PLAINS LATE THIS COMING WEEK AND NEXT WEEKEND WITH PRETTY DECENT CHANCES FOR SHOWERS/STORMS. LATE IN THE PERIOD SHOULD FEATURE SOME DRYNESS AS SFC HIGH BUILDS INTO THE AREA. TEMPERATURES SHOULD AVERAGE OUT NEAR NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1222 PM CDT SAT JUL 11 2015 OTHER THAN SOME MVFR CLOUDS EARLY THIS AFTERNOON AND LATE TNT...THE REST OF THE TAF PERIOD SHOULD MOSTLY VFR. LATE AFTN/EVENING THUNDERSTORMS ARE POSSIBLE AT KABR/KATY BUT FOR NOW CONFIDENCE AND EXPECTED COVERAGE IS LOW ENOUGH TO LEAVE OUT OF THE FORECAST. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR SDZ006>008-011- 018>023. MN...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR MNZ039-046. && $$ SHORT TERM...CONNELLY LONG TERM...TDK AVIATION...TDK
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1218 PM CDT SAT JUL 11 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 355 AM CDT SAT JUL 11 2015 MODELS CONTINUE TO BRING WEAK THERMAL SUPPORT FOR SHOWER AND THUNDERSTORM DEVELOPMENT EAST ACROSS THE AREA THIS MORNING. SHORT TERM MODELS SUCH AS THE HRRR AND HOP/WRF KEEP THE CONVECTION VERY SPOTTY AND THIS LOOKS REASONABLE. WILL KEEP POPS AT CHANCE FOR NOW AND ENHANCE AS DEVELOPMENT WARRANTS. THIS ACTIVITY SHOULD DECREASE TO THE EAST NORTHEAST THIS AFTERNOON AS CAPPING FROM INCREASINGLY WARM AIR SPREADS INTO THE AREA. BY LATE IN THE DAY THIS ACTIVITY...IF THERE IS ANY LEFT...SHOULD BE CONFINED TO THE FAR EASTERN PART OF THE AREA WITH SOME MINIMAL NEW DEVELOPMENT POSSIBLE. MEANWHILE...STRONG WARMING OVER THE WESTERN PART OF THE AREA MAY INCLUDE ENOUGH HEATING TO BREAK THE CAP FAR WEST LATE THIS AFTERNOON AS THE DRYLINE GETS CLOSER. THIS IDEA WAS DEEMED REASONABLE IN THE EARLIER FORECAST AND STILL LOOKS SO...BUT AGAIN ACTIVITY SHOULD BE PRETTY SPARSE. THE SURGE OF WARMING AND HEATING SHOULD TAKE TEMPERATURES UP TO THE 90S WEST...WITH INCREASINGLY HUMID 80S EAST. LOW CLOUDS WHICH WILL BE PREVALENT IN AREAS EAST THIS MORNING SHOULD HEAT OUT AND GENERALLY DECREASE LATE MORNING AND AFTERNOON. FOR TONIGHT WILL KEEP SOME CHANCE OF STORMS FAR EAST WITH THE STRONG INSTABILITY. OTHERWISE A WARM NIGHT IS IN STORE WITH LOW TEMPERATURES WITHING A COUPLE DEGREES OF 70 EVERYWHERE. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 355 AM CDT SAT JUL 11 2015 HEAT AT THE FOREFRONT OF MID RANGE CONCERNS. CAPPED ENVIRONMENT WILL BE IN PLACE WITH STRONG ELEVATED MIXED LAYER TRAPPING NEAR SURFACE MOISTURE QUITE EFFECTIVELY ACROSS MUCH OF THE AREA THROUGH THE DAY. LIKELIHOOD OF SOME CONVECTION TO OUR SOUTH AGAIN THIS EVENING WILL ACT TO MODIFY ENVIRONMENT TO SOME DEGREE...AND SOUTH TO SOUTHEAST FLOW NEAR THE SURFACE WILL REINFORCE PRESENCE OF BOUNDARY LAYER MOISTURE INTO THE AFTERNOON FROM THE JAMES VALLEY EASTWARD. EVENTUALLY...APPEARS AS IF THE SURFACE TROUGH WILL BE PUSHING INTO THE JAMES VALLEY OR A BIT EAST BY LATE SUNDAY AFTERNOON...AND OTHER THAN A BUFFER OF SLIGHTLY BETTER MIXING JUST TO THE EAST OF THIS... MIXING WILL BE QUITE CHALLENGED BY THE STRONG INVERSION. AS A RESULT...WILL PROBABLY NOT GET QUITE AS TOASTY FROM AROUND I29 EASTWARD...BUT STILL PLENTY WARM INTO THE LOWER 90S...WHILE AREAS WEST OF THE TROUGH ARE LIKELY TO FIND A FEW SPOTS REACHING THE CENTURY MARK...AS DEWPOINTS MIX GREATLY INTO THE 50S. EVEN WITH THE SLIGHTLY LOWER TEMPERATURE EXPECTATIONS...DEWPOINTS WILL SOAR WELL INTO THE 70S...AND WILL RESULT IN A LARGE AREA OF 100 TO 105 DEGREE AFTERNOON HEAT INDEX. JAMES VALLEY LOCATIONS WILL HAVE THE WORST EARLY AFTERNOON BEFORE START TO SEE MIXING LOWERING THE MOISTURE CONTENT. WITH THE LONG PERIOD SINCE LAST EXTREME HEAT AND THE NUMEROUS OUTDOOR ACTIVITIES ON THE WEEKEND...HAVE DECIDED TO ISSUE HEAT ADVISORY FROM THE JAMES VALLEY EASTWARD THROUGH THE AFTERNOON ON SUNDAY. NOT TOTALLY IMPOSSIBLE TO FIND A ROGUE HIGH BASED THUNDERSTORM TO START THE DAY...BUT SUCH A LOW CHANCE THAT HAVE KEPT CLEAR OF THE FORECAST. OTHERWISE...WAVE WILL BEGIN TO PUSH ACROSS THE MEAN UPPER RIDGE DURING SUNDAY AFTERNOON AND EVENING...AND START TO ERODE SOME OF THE WARMEST AIR ALOFT. REALLY HARD TO PICTURE THERE BEING ENOUGH LIFT TO BREAK RESIDUAL INVERSION EVEN AFTER FULL HEATING...WITH CIN LIKELY IN THE 50-150 J/KG RANGE FOR MOST LOCATIONS. OUTSIDE CHANCE THERE COULD BE A GOLDILOCKS LOCATION WHERE THE WEAKENING CAP AND FORCING ARE JUST RIGHT...BUT AT THIS POINT NOT WORTH CLUTTERING THE FORECAST WITH ISOLATED THREAT. HOWEVER...KEEP AWARE...AS THERE IS MORE THAN ENOUGH POTENTIAL INSTABILITY TO MAKE FOR A STRONGER STORM. PERHAPS A BIT BETTER CHANCE FOR THINGS TO COME TOGETHER OVER THE NORTHEASTERN CWA CLOSEST TO THE UPPER FORCING DURING THE EVENING...BUT SHOULD BE A PRETTY QUICKLY CLOSING WINDOW AS STRONGER FORCING MOVES QUICKLY PAST AND DEEPER DRYING ON WEST TO NORTHWEST FLOW SPREADS ACROSS THE AREA. NEAR SURFACE WINDS WILL DECOUPLE AND ALLOW THE SURFACE TO RECOVER QUITE A BIT IN THOSE FULLY MIXED AREAS...AND RETAIN SOME UPPER 60S DEWPOINT VALUES IN THE SOUTHEAST. ON MONDAY...AS SHOULD BE ANOTHER VERY WARM DAY...THE VERY HUMID CONDITIONS WILL BE RELAXED SOMEWHAT OVER A GOOD PORTION OF THE AREA...WITH HIGHEST READINGS EAST OF I 29 DURING THE MORNING HOURS. DEEPER MIXING SHOULD TAKE DEWPOINTS INTO THE 50S WEST TO LOWER TO MID 60S EAST DURING THE AFTERNOON...WITH WINDS AT 15 TO 25 MPH AT TIMES. THE HEAT INDEX WILL AGAIN CLIMB INTO THE 90S. WILL HAVE TO SEE IF WE GET ANOTHER INCREASE IN SMOKE BEHIND THE BOUNDARY AS IT PUSHES SOUTHWARD SUNDAY NIGHT/MONDAY...AS COULD IMPACT TEMPS A COUPLE DEGREES. THE EXTENDED RANGE FROM TUESDAY THROUGH FRIDAY WOULD SEEMINGLY BE A BIT MORE ACTIVE IN GENERAL...WITH RIDGE ACROSS THE NORTHERN PLAINS...BREACHED PERIODICALLY WITH SYSTEMS COMING OUT OF THE WEST TO SOUTHWEST FLOW ALOFT. A COMMON FEATURE IN MODELS IS WAVE AROUND WEDNESDAY...AND HAVE MAINTAINED HIGHER PRECIP CHANCES WITH THIS FEATURE. TEMPS SHOULD REMAIN FROM NORMAL TO SLIGHTLY ABOVE NORMAL... BUT WILL HAVE TO WATCH TO SEE IF SLIGHTLY MORE AMPLIFIED SOLUTION IN ECMWF COULD KEEP A BETTER BACKDOOR BOUNDARY AROUND MIDWEEK. ANOTHER WAVE HAS PROXIMITY TO THE END OF THE FORECAST CYCLE...BUT DRASTICALLY DIFFERING TIMING IN GREATER ENSEMBLE OF SOLUTIONS FOR SURFACE REFLECTION. WATCHING FOR ANOTHER EASTWARD SURGE IN WARMER AIR AHEAD OF THIS WAVE...WHICH COULD BE ON THE WAY FOR LATE WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1216 PM CDT SAT JUL 11 2015 MVFR CEILINGS OVER PORTIONS OF THE AREA WILL CONTINUE TO BREAK UP THROUGH MID AFTERNOON. OTHERWISE...VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR SDZ038>040- 053>056-059>062-065>071. MN...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR MNZ071-072-080- 081-089-090-097-098. IA...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR IAZ001>003- 012>014-020>022-031-032. NE...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR NEZ013-014. && $$ SHORT TERM... LONG TERM...CHAPMAN AVIATION...JM
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1212 PM CDT SAT JUL 11 2015 .DISCUSSION... SEE 18Z AVIATION DISCUSSION. && .AVIATION... HI-RES ARW AND NMM SUPPORT MORE WIDESPREAD SHRA/TSRA THIS AFTN THAN THE GFS/ECMWF. THE RAP IS SOMEWHERE IN BETWEEN SO THOUGHT THE NAM/RAP WAS A GOOD COMPROMISE. PW VALUES WILL PEAK NEAR 2.00 INCHES THIS AFTN SO FEEL VCSH IS WARRANTED. WILL WATCH TREND AND MAY HAVE TO CARRY THUNDER LATER THIS AFTN AS THERE APPEARS TO BE ENOUGH INSTABILITY PRESENT TO GENERATE THUNDER. FCST SOUNDINGS SHOW LESS POTENTIAL FOR LOW CLOUDS OVERNIGHT SO WENT GENERALLY VFR. COULD GET SOME FOG AT KCXO PRIOR TO SUNRISE. VFR/DRY ON SUNDAY WITH LIGHT WINDS. 43 && .PREV DISCUSSION... /ISSUED 1040 AM CDT SAT JUL 11 2015/ UPDATE... MORNING UPPER AIR ANALYSIS SHOWED THE UPPER RIDGE HAD SPREAD FARTHER WEST FROM EVENING OBSERVATIONS... WITH 1-2 DECAMETER HEIGHT RISES SEEN OVER PARTS OF TEXAS...LOUISIANA...AND OKLAHOMA. SIMILAR TO YESTERDAY... GOES SOUNDER IMAGERY SHOWS A PLUME OF 1.6 TO 1.8 INCH PRECIPITABLE WATER VALUES PUSHING INTO SOUTHEAST TEXAS. THIS PLUME APPEARS TO HAVE PUSHED FARTHER INLAND THAN THIS TIME YESTERDAY HOWEVER /ROUGHLY ALONG AND SOUTH OF THE 59 CORRIDOR NOW/ AND A FEW SHOWERS HAVE ALREADY DEVELOPED IN LIBERTY AND CHAMBERS COUNTIES. AS DEEPER MOISTURE THIS MORNING SPREADS INLAND... ADDITIONAL HEATING WILL CONTRIBUTE TO ISOLATED TO SCATTERED SHOWER AND THUNDERSTORM DEVELOPMENT THROUGH EARLY EVENING. CURRENT FORECAST HANDLES TRENDS WELL WITH NO MAJOR CHANGES MADE. HUFFMAN PREV DISCUSSION... /ISSUED 404 AM CDT SAT JUL 11 2015/ DISCUSSION... AREA RADAR THIS MORNING SHOWS A FEW ISO SHOWERS OFF THE COAST IN THE GULF WHERE GOES SATELLITE DERIVED PRECIP WATER VALUES ARE AROUND 1.8 INCHES. THIS HIGHER MOISTURE SHOULD CONTINUE TO MOVE INLAND TODAY AND SUPPORT AT LEAST SOME ISO TO WIDELY SCT SHOWER AND THUNDERSTORM ACTIVITY. UPPER LEVEL ANALYSIS AT 500MB SHOWS 594/595 DM RIDGE OVER MUCH OF THE NORTHERN GULF INCLUDING SE TX. WHILE HIGHER MOISTURE AND DAYTIME HEATING SHOULD SUPPORT THUNDERSTORM CHANCES...THINK AT LEAST SOME SUBSIDENCE WILL LIMIT THE ACTIVITY. FORECAST WILL CONTINUE WITH 20 POPS FOR MUCH OF THE AREA TODAY. UPPER LEVEL RIDGE WILL EXPAND AND MOVE OVER MUCH OF TX AND S PLAINS BY SUNDAY. THE RIDGE WILL REMAIN QUASI-STATIONARY OVER THE S PLAINS AND TX FOR MUCH OF THE COMING WEEK. THE RIDGE MAY WEAKEN SLIGHTLY FOR THE END OF THE COMING WEEK. HIGHER MOISTURE MAY ALSO MOVE INTO THE REGION FROM THE GULF WHICH WILL BRING BACK A MENTION OF THUNDERSTORM CHANCES FOR NEXT FRI/SAT. TEMPERATURES FOR THE COMING WEEK WILL BE CLOSE TO CLIMO NUMBERS OR MAYBE A COUPLE DEGREES HIGHER. HOUSTON IAH STILL HAS NOT REACHED 95 DEGREES FOR A HIGH TEMPERATURE THIS YEAR. IT LOOKS LIKE THAT MARK WILL BE REACHED SUN/MON. HIGH TEMPS IN THE MID 90S LOOK REASONABLE FOR THE REST OF THE WEEK WITH LOW TEMPS IN THE MID/UPPER 70S. 39 MARINE... VERY LITTLE CHANGE TO ONGOING MARINE FCST. TYPICAL SUMMERTIME PATTERN MOSTLY PREVAILING INTO NEXT WEEK WITH LIGHT TO OCCASIONALLY MODERATE ONSHORE WINDS. SPEEDS OFFSHORE USUALLY A BIT STRONGER AT NIGHT THAN DURING THE DAY. 47 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 75 94 74 96 74 / 10 10 10 10 10 HOUSTON (IAH) 76 94 75 95 75 / 10 10 10 10 10 GALVESTON (GLS) 81 91 80 92 81 / 10 10 10 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...14 AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1247 PM CDT SAT JUL 11 2015 .UPDATE... ISSUED AT 1146 AM CDT SAT JUL 11 2015 HAVE BEEN WORKING THROUGH THE MORNING AT TRYING TO KEEP AHEAD OF THE WEATHER. SHORTWAVE TROUGH ENERGY UPSTREAM MOVING AT THE AREA IS PROVIDING ENOUGH LIFT WITH WEAK WARM ADVECTION AND MINOR MUCAPE /250 J/KG/ OF INSTABILITY TO POP SHOWERS AND ISOLATED THUNDER. BELIEVE THE AREA WILL CONTINUE TO MOVE EAST THROUGH THE DAY AND FEEL SOME DIMINISHMENT MAY OCCUR AS IT DOES. BEHIND THE WAVE...BELIEVE MANY HOURS OF DRY WEATHER WILL HOLD WITH LITTLE FORCING UNTIL AFTER MIDNIGHT. HAVE LOWERED THE RAIN CHANCES BEHIND THE WEATHER UNTIL LATER TONIGHT...BUT AM STILL ASSESSING LATER INTO THE OVERNIGHT. SUBSTANTIAL CLOUD AND RAIN HAS CAUSED TEMPERATURES TO REALLY STAY COOL. HAVE LOWERED HIGHS TODAY SOME...BUT SOME LATE SUN COULD POP THEM UP FAST. SO...HAVE KEPT THE AFTERNOON COOL WITH A LATE JUMP. RAIN RATES ARE PRETTY IMPRESSIVE WITH SUCH LITTLE CAPE. THESE LITTLE SHOWERS ON RADAR ARE CAUSING SOME GOOD DOWNPOURS. 50DBZ CORE NEAR AUTIN MN CAUSED 0.75 INCHES OF RAIN IN A SHORT AMOUNT OF TIME. HERE COMES THE HIGHER PRECIPITABLE WATER WITH 1.5 INCH && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 339 AM CDT SAT JUL 11 2015 REGIONAL RADARS THIS MORNING SHOWING SOME CONVECTION THIS MORNING OVER NORTHERN MISSOURI WITH ANOTHER AREA OF CONVECTION OVER EASTERN NEBRASKA. THIS ACTIVITY IS NORTH OF A WARM FRONT THAT EXTENDS ACROSS NORTHERN KANSAS AND MISSOURI AND AHEAD OF A WEAK TROUGH OF LOW PRESSURE FROM KANSAS INTO NORTH DAKOTA. WATER VAPOR SATELLITE SHOWS ONE SHORT WAVE TROUGH OVER NEBRASKA AND KANSAS WITH ANOTHER OVER NORTH DAKOTA. THE TREND IN THE 11.00Z MODELS AND 11.03Z RAP IS FOR THE WAVE OVER NEBRASKA AND KANSAS TO FLATTEN OUT AS IT MOVES NORTHEAST INTO THE TOP PART OF THE RIDGE AXIS OVER THE CENTRAL PART OF THE COUNTRY. THE WAVE OVER NORTH DAKOTA WILL ALSO CONTINUE TO MOVE NORTHEAST INTO SOUTHERN CANADA THROUGH THE DAY. THE SURFACE WARM FRONT SHOULD LIFT SLOWLY TO THE NORTH WITH A GENERAL MODEL CONSENSUS OF IT REACHING ABOUT THE IOWA/MISSOURI BORDER. THIS WILL KEEP THE BEST MOISTURE TRANSPORT WELL SOUTH OF THE AREA TODAY AND SHOULD KEEP MOST OF THE RAIN TO THE SOUTH AS WELL. THE MESO MODELS SEEMED TO HAVE LATCHED ON TO THIS AS WELL WITH THE 11.00Z CR-NAM NEST...HI-RES ARW AND NMM KEEPING THE AREA DRY WHILE THE 11.00Z NAM12 AND 11.05Z HRRR STILL TRY TO BRING THE REMAINS OF SOME DEVELOPING CENTRAL IOWA CONVECTION INTO THE SOUTHERN SECTIONS FOR THIS MORNING. BASED ON ALL THESE SOLUTIONS...HAVE TRENDED THE RAIN CHANCES DOWN FOR TODAY WITH ABOUT A 20 PERCENT CHANCE ACROSS THE NORTH TO AT MOST A 40 PERCENT CHANCE IN THE SOUTH. THESE COULD STILL BE TOO HIGH AS IT COULD END UP BEING TOTALLY DRY NORTH OF THE IOWA/MINNESOTA BORDER. UPPER LEVEL HEIGHTS SHOULD BUILD A LITTLE BIT OVER THE REGION TONIGHT AS THE SHORT WAVE TROUGHS MOVE OFF TO THE EAST. THE WARM FRONT WILL CONTINUE TO LIFT SLOWLY NORTH TAKING ON A MORE NORTHWEST TO SOUTHEAST ORIENTATION FROM A DEVELOPING AREA OF LOW PRESSURE OVER NORTH DAKOTA INTO CENTRAL ILLINOIS. THE NAM REALLY RAMPS UP THE MOISTURE TRANSPORT INTO THIS BOUNDARY AROUND 06Z SUNDAY AND BREAKS OUT CONVECTION NORTH OF THE BOUNDARY AND ACROSS THE AREA. THE 11.00Z GFS SOMEWHAT HINTS AT THIS AS WELL WHILE THE 11.00Z ECMWF KEEPS THE BOUNDARY FARTHER SOUTH AND MOST OF THE RAIN TO THE SOUTH AS WELL. THE HI-RES NMM IS SIMILAR TO THE NAM WHILE THE HI-RES ARW IS COMPLETELY DRY FOR TONIGHT. CONCERNED THAT THE NAM IS TOO STRONG WITH THE MOISTURE TRANSPORT TONIGHT AND WILL ONLY CARRY A GENERAL 30 TO 40 PERCENT CHANCE ACROSS THE AREA. THE REAL ACTION AND BEST CHANCES FOR RAIN MAY COME SUNDAY NIGHT. A SHORT WAVE TROUGH IS EXPECTED TO COME OUT OF THE WEAKENING UPPER LEVEL LOW CURRENTLY OVER OREGON AND NEVADA. THIS WAVE SHOULD TOP THE UPPER LEVEL RIDGE AND THEN SLIDE SOUTHEAST ACROSS THE AREA SUNDAY NIGHT. THE GFS SUGGESTS THIS WAVE WILL PRODUCE SOME MODERATE PV ADVECTION IN THE 500-300 MB LAYER AS IT COMES ACROSS. THIS LIFT SHOULD BE AIDED BY SOME JET DYNAMICS FROM THE LEFT EXIT REGION OF THE 300 MB JET AS THIS COMES IN WITH THE SHORT WAVE TROUGH. THE WARM FRONT SHOULD CONTINUE TO EDGE NORTH EXTENDING FROM EASTERN NORTH DAKOTA INTO ILLINOIS WITH THE GFS SHOWING WEAK TO MODERATE FRONTOGENESIS IN THE 1000-850 MB LAYER NORTH OF THE FRONT. AS THE SHORT WAVE TROUGH APPROACHES...A CONVECTIVE COMPLEX SHOULD FROM LATE SUNDAY AFTERNOON OVER THE EASTERN DAKOTAS AND THEN SLIDE SOUTHEAST THROUGH THE NIGHT ALONG AND NORTH OF THE WARM FRONT. THERE SHOULD STILL BE AMPLE CAPE AVAILABLE FOR THE STORMS TO WORK WITH AS THEY MOVE INTO THE AREA. THE GFS SUGGESTS UP TO 2500 J/KG OF ML CAPE SUNDAY EVENING ONLY DROPPING OFF TO 1500 J/KG DURING THE OVERNIGHT HOURS. UP TO 40 KNOTS OF SHEAR SHOULD MOVE IN AHEAD OF THE SHORT WAVE TROUGH WITH THIS BEING PRIMARILY IN THE 0-3 KM LAYER. THIS WILL PRESENT THE OPPORTUNITY FOR A NOCTURNAL MCS TO ROLL ACROSS THE AREA WITH A SEVERE WIND THREAT. HAIL DOES NOT LOOK TO BE MUCH OF THREAT WITH WARM CLOUD DEPTHS ON THE ORDER OF 3.5 TO 4 KM...BUT THERE SHOULD BE SOME GOOD RAINFALL RATES AND LOCALLY HEAVY RAINS. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 339 AM CDT SAT JUL 11 2015 THE UPPER LEVEL RIDGE SHOULD BRIEFLY BUILD BACK OVER THE REGION EARLY IN THE WEEK BEFORE FLATTENING OUT WITH ZONAL FLOW OVER THE UPPER MIDWEST. THIS PATTERN LOOKS TO BE A DIRTY FLOW WITH THE POTENTIAL FOR SEVERAL SHORT WAVE TROUGHS TO BE EMBEDDED IN THE FLOW AND COME ACROSS THE REGION. DECENT AGREEMENT IN TIMING OF A WAVE FOR WEDNESDAY BETWEEN THE ECMWF AND GFS...BUT DIFFERENCES IN STRENGTH WITH THE GFS BEING STRONGER. AFTER THAT...CONSIDERABLE DIFFERENCES IN HOW AN UPPER LEVEL LOW COMING ACROSS SOUTHWEST CANADA IS HANDLED. THE GFS OPENS THIS SYSTEM UP AND BRINGS IT TOWARD THE AREA BY THE END OF THE WEEK WHILE THE ECMWF KEEPS IT AS A CLOSED LOW HOLDING IT BACK WITH RIDGING OVER THE REGION. WITH ALL THE UNCERTAINTY...WILL STAY WITH GENERAL 20 TO 40 PERCENT CHANCES THROUGH THE PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1247 PM CDT SAT JUL 11 2015 EXPECT AN IMPROVING TREND OVER THE NEXT HOURS AT KRST AS IFR CIGS WILL GIVE WAY TO MVFR. THERE WILL BE THE POSSIBILITY OF MVFR IF SOME SHOWERS WORK INTO KLSE BUT LATEST 60 MINUTES OF RADAR INDICATE A DIMINISHING TREND. OVERNIGHT ABUNDANT LOW LEVEL MOISTURE AND CLEAR SKIES...IN CONCERT WITH COOLER HIGHS TODAY UNDER THE CLOUDS...WILL SET UP THE DEVELOPMENT OF LOW CLOUDS AND FOG AS THE OVERNIGHT PROGRESSES. THIS IS ALL NORTHEAST OF A WARM FRONT WHICH WILL BE LOCATED NEAR I-35. THIS CLOUD AREA WILL BE WIDESPREAD ACROSS THE REGION...ANCHORED IN WI. THE CLOUDS ARE EXPECTED TO LIFT AND MIX OUT THROUGH THE MORNING HOURS SUNDAY FROM WEST TO EAST. CONFIDENCE IN THE MORNING IFR CLOUD FORECAST IS MEDIUM. THERE COULD BE SOME LOWER VSBYS SHOULD IT ALL COME TOGETHER IDEALLY. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...BAUMGARDT SHORT TERM...04 LONG TERM....04 AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1233 PM CDT SAT JUL 11 2015 UPDATED AVIATION SECTION .UPDATE... MESO MODELS CONTINUE TO JUST BRUSH SOUTHERN WI WITH PRECIP THROUGH THE AFTERNOON. THE PRECIP IS ON THE NORTHERN EDGE OF A REMNANT MCV THAT WILL BE ROLLING ACROSS NORTHERN WI TODAY. THERE IS STILL A SMALL CHANCE FOR SHOWERS AND MAYBE A RUMBLE OF THUNDER ACROSS THE WHOLE MKX FORECAST AREA THROUGH MID AFTERNOON DUE TO SOME WEAK WARM AIR ADVECTION ALOFT. THE DRY AIR IN PLACE OVER THE AREA WILL KEEP MOST OF THE PRECIP FROM REACHING THE GROUND. LOWERED POPS ACCORDINGLY. THE LATEST 12Z MODELS COMING IN ARE NOW SHOWING A DRIER FORECAST FOR TONIGHT AS WELL. SPC REMOVED OUR FORECAST AREA FROM THE MARGINAL RISK FOR SEVERE WEATHER NOW. TEMPERATURES WILL BE GREATLY AFFECTED BY EXTENSIVE CLOUD SHIELD OVER SOUTHERN WI TODAY. HIGHS WILL STRUGGLE TO REACH THE UPPER 70S NEAR THE IL BORDER... BUT ARE ALREADY AROUND 80 TOWARD SHEBOYGAN WITH MORE SUNSHINE. && .AVIATION/18Z TAFS/... SHOWERS WITH A POSSIBLE RUMBLE OF THUNDER WILL TRACK ACROSS FAR SOUTH CENTRAL WI AND GRADUALLY DIMINISH AS THEY REACH SOUTHEAST WI BY MID AFTERNOON. THESE ARE ON THE NORTHERN EDGE OF PRECIP CROSSING NORTHERN IL. THERE IS A SMALL CHANCE FOR SHOWERS ELSEWHERE THROUGH THE AFTERNOON DUE TO WEAK WARM AIR ADVECTION ALOFT. THERE IS PLENTY OF DRY AIR OVER SOUTHERN WI SO SOME OF THE SHOWERS SHOWING UP ON COMPOSITE RADAR ARE NOT REACHING THE GROUND... APPARENT ON THE LOCAL MKX RADAR. THERE MAY BE VIRGA INSTEAD. CHANCES FOR SHOWERS AND THUNDERSTORMS ARE NOW DIMINISHING FOR TONIGHT AS MODELS ARE TRENDING TOWARD A DRIER FORECAST. I HAVE LOW CONFIDENCE ABOUT CHANCES FOR IFR CIGS/VSBY TONIGHT. SOUTHERN WI WILL BE ON THE NORTH SIDE OF THE SURFACE WARM FRONT WHICH IS TYPICALLY A GOOD SETUP FOR LOW CLOUDS AND FOG. HOWEVER... THE LACK OF WIDESPREAD RAIN AND HIGH DEWPOINTS MAY PRECLUDE THEIR DEVELOPMENT. && .PREV DISCUSSION... /ISSUED 326 AM CDT SAT JUL 11 2015/ TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM. 500 MB RIDGE AXIS AND SFC HIGH PRESSURE EXITS THE REGION EARLY SATURDAY MORNING AS A SHORTWAVE TROUGH AND LOW LEVEL WARM AIR ADVECTION ALONG A WARM FRONT MAKES ITS WAY INTO THE REGION. MAINLY HIGH CLOUDS IN THE AREA AHEAD OF THE SHORTWAVE. SOME -SHRA CAN BE SEEN IN SOUTHEAST IOWA AT 08Z SATURDAY...MOVING NORTHEAST AHEAD THE LOW LEVEL BAROCLINIC ZONE. HIGHS SATURDAY LOOK TO BE NEAR 80F ACROSS S WI...AS 925 MB TEMPS ARE PROGGED TO BE NEAR 20C BY THE GFS. 925 MB TEMPERATURES WILL ONLY INCREASE FROM THERE AS WARM FRONT TRANSLATES NORTHEAST. 11.06 HRRR MESO MODEL IS SHOWING THE BULK OF THE PRECIPITATION DURING THE DAY SATURDAY TO BE SOUTH OF THE WI/IL BORDER AS THE HRRR IS PROGGING AN MCV DEVELOPING ACROSS N IL. THIS IS INDICATED IN THE GFS MODEL AS WELL...KEEPING THE STRONGEST MID-LEVEL SUPPORT SOUTH AS ISENTROPIC OMEGA VALUES REACH NEARLY 9 UBAR/S IN THE GFS. SO...REDUCED THE POPS DURING THE DAY SATURDAY. THE BEST CHANCES OF PRECIPITATION WILL BE SATURDAY NIGHT AS THE BEST WARM AIR ADVECTION AND INSTABILITY AXIS REACHES S WI. KEPT LIKELY POPS AS BETTER 850-700 MB FRONTOGENETICAL FORCING AND 850-700 MB Q- VECTOR CONVERGENCE CREEPS INTO THE REGION DURING THIS TIME. THERE IS A MARGINAL RISK FOR SEVERE WEATHER SOUTHWEST OF A JANESVILLE TO CROSS PLAINS TO LOGANVILLE LINE. GOOD INSTABILITY WILL DEVELOP IN THE EVENING AND OVERNIGHT HOURS SATURDAY INTO SUNDAY AS THE LOW LEVEL WAA COMES IN. MOST UNSTABLE CAPE VALUES ARE PROGGED TO REACH 2500+ J/KG ACCORDING TO THE GFS...WHILE THE NAM AND ECMWF ARE SHOWING MUCAPE ONLY AOA 1000 J/KG. SUNDAY - CONFIDENCE...MEDIUM GRADUAL BUILDING OF HEIGHTS WITH ONE SHORTWAVE EXITING THE WESTERN GREAT LAKES REGION. GFS BLOWS UP ANOTHER ONE WITHIN THE BUILDING HEIGHTS REGIME BUT THIS APPEARS TO BE ERRONEOUS WITH OTHER MODELS SHOWING A CLEANER BUILDUP OF THE MID LEVEL RIDGE AXIS. MODELS SHOW SOME LINGERING SHRA/PSBL TSRA PRIOR TO 18Z WITH INFLUENCE OF THE DEPARTING WAVE AND 850/925 BAROCLINICITY. THE 850 FRONT SHIFTS FURTHER NE WITH 925 TEMPS REALLY SOARING THOUGH THE 12Z ECMWF HANGS ONTO THIS BOUNDARY LONGER WHICH SHOWS A COOLER REGIME THAN WHAT THE NAM/GFS IMPLIES. THE GFS SOUNDINGS SHOW CAPES BUILDING UP TO 3000 J/KG WITH INVERSION JUST UNDER 5K FEET. SOME AREAS SEEING SIGNIFICANT CIN DEVELOPING. LIFT BECOMES LESS DISCERNIBLE IN THE AFTERNOON NORTHWARD SHIFT OF WARM FRONT AND ANY UPPER FORCING QUESTIONABLE GIVEN THE PROGGD ERRONEOUS VORT BULLSEYE ON THE GFS. WILL GO WITH TEMPS WELL INTO THE 80S WITH SOME ONSHORE COOLING EFFECTS IN THE EAST. SUNDAY NIGHT INTO MONDAY - CONFIDENCE...MEDIUM EXPECTING AN MCS TO RIDE ALONG LOWER LEVEL BAROCLINICITY LATER SUNDAY NIGHT. UPPER LEVEL JET WILL BE FAVORABLY PLACED WITH LEFT FRONT QUADRANT AND MID LEVEL WAVE RIDING INTO THE UPPER MIDWEST. THE NAM AND GFS SHOW GREATEST WINDOW OF CONCERN BETWEEN 06-12Z. THE 12Z ECMWF WAS SHOWING A SLOWER SOLUTION WITH 12-18Z BEING MORE PRIME. THE LATEST ECMWF SHOWS A LITTLE QUICKER SOLUTION. AIRMASS WILL BE RATHER UNSTABLE THROUGH THE NIGHT. PER SPC DISC FOR SWODY2 THE CONVECTION AFFECTING SRN WI WILL HAVE EVOLVED INTO MORE OF A WIND EVENT AS THESE STORMS RIDE IN NW-SE. CONVECTIVE REDEVELOPMENT WILL HINGE ON HOW BOUNDARIES LAY OUT AFTER THE MORNING STORMS. MID LEVEL FLOW STILL CYCLONIC WITH 250 JET STILL POSITIONED TO OUR SOUTHWEST WITH DIVERGENCE STILL NOTED ACROSS THE AREA. IF AIRMASS CAN RELOAD LOOKING AT CAPE BUILDUP WITH AFTERNOON STORMS ASSOCIATED WITH SURFACE TROUGH...BUT AGAIN LOTS WILL DEPEND ON HOW AIRMASS SETS UP AFTER THE MORNING ACTIVITY. ATTM SPC SWODY3 IS KEYING ON THIS BEING MORE ROBUST FURTHER SOUTH OF OUR CWA PROBABLY MORE CO-LOCATED WITH THE OUTFLOW FROM EARLIER STORMS. TUESDAY - CONFIDENCE...LOW ECMWF/NAM SHOW WEAK SURFACE TROUGH LINGERING WHILE THE GFS SHIFTS BOUNDARY TO OUR SOUTH WITH NE WINDS AND HIGH PRESSURE NOSING IN. SO NEED TO RETAIN SOME POPS FOR THE SLOWER SOLUTIONS WHICH INCLUDES THE NAM AS WELL. ECMWF SHOWS A FAIRLY POTENT WAVE ARRIVINGDURING PRIME TIME AS WELL. HOPEFULLY FUTURE MODEL RUNS WILL COME INTO BETTER AGREEMENT ON THIS. TUESDAY NIGHT AND WEDNESDAY - CONFIDENCE...MEDIUM MODELS SHOW HIGH PRESSURE BUILDING IN WITH NE-E FLOW AND COOLER AIRMASS. THURSDAY AND FRIDAY - CONFIDENCE...LOW THE 00Z ECMWF ESSENTIALLY KEEPS THE INFLUENCE OF THE HIGH IN PLACE THIS PERIOD AS NEXT TROUGH AND ASSOCIATED PRECIP HANGS OUT IN THE PLAINS. THE GFS IS MORE PROGRESSIVE AND SHOWS A MORE ACTIVE PERIOD WITH POTENTIALLY SEVERAL ROUNDS OF PRECIP. GIVEN THE DISPARITY WILL LEAN ON THE SUPERBLEND POPS FOR NOW. AVIATION/12Z TAFS/...VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH SATURDAY MORNING UNTIL LOWER LEVEL CLOUDS AND PERHAPS SOME -SHRA MOVE INTO THE REGION. A MID-LEVEL SHORTWAVE TROUGH WILL SWEEP IN TO THE AREA ALONG WITH A PUSH OF WARMER AIR IN THE 925-850 MB LAYER. BEST CHANCES OF PRECIPITATION WILL BE SATURDAY EVENING AND OVERNIGHT AS BETTER FORCING ARRIVES AT THAT TIME. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...MRC TODAY/TONIGHT AND AVIATION/MARINE...JTS SUNDAY THROUGH FRIDAY...COLLAR
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1206 PM CDT SAT JUL 11 2015 .UPDATE... MESO MODELS CONTINUE TO JUST BRUSH SOUTHERN WI WITH PRECIP THROUGH THE AFTERNOON. THE PRECIP IS ON THE NORTHERN EDGE OF A REMNANT MCV THAT WILL BE ROLLING ACROSS NORTHERN WI TODAY. THERE IS STILL A SMALL CHANCE FOR SHOWERS AND MAYBE A RUMBLE OF THUNDER ACROSS THE WHOLE MKX FORECAST AREA THROUGH MID AFTERNOON DUE TO SOME WEAK WARM AIR ADVECTION ALOFT. THE DRY AIR IN PLACE OVER THE AREA WILL KEEP MOST OF THE PRECIP FROM REACHING THE GROUND. LOWERED POPS ACCORDINGLY. THE LATEST 12Z MODELS COMING IN ARE NOW SHOWING A DRIER FORECAST FOR TONIGHT AS WELL. SPC REMOVED OUR FORECAST AREA FROM THE MARGINAL RISK FOR SEVERE WEATHER NOW. TEMPERATURES WILL BE GREATLY AFFECTED BY EXTENSIVE CLOUD SHIELD OVER SOUTHERN WI TODAY. HIGHS WILL STRUGGLE TO REACH THE UPPER 70S NEAR THE IL BORDER... BUT ARE ALREADY AROUND 80 TOWARD SHEBOYGAN WITH MORE SUNSHINE. && .AVIATION/18Z TAFS/... SHOWERS WITH A POSSIBLE RUMBLE OF THUNDER WILL TRACK ACROSS FAR SOUTH CENTRAL WI AND GRADUALLY DIMINISH AS THEY REACH SOUTHEAST WI BY MID AFTERNOON. THESE ARE ON THE NORTHERN EDGE OF PRECIP CROSSING NORTHERN IL. THERE IS A SMALL CHANCE FOR SHOWERS ELSEWHERE THROUGH THE AFTERNOON DUE TO WEAK WARM AIR ADVECTION ALOFT. THERE IS PLENTY OF DRY AIR OVER SOUTHERN WI SO SOME OF THE SHOWERS SHOWING UP ON COMPOSITE RADAR ARE NOT REACHING THE GROUND... APPARENT ON THE LOCAL MKX RADAR. THERE MAY BE VIRGA INSTEAD. CHANCES FOR SHOWERS AND THUNDERSTORMS ARE NOW DIMINISHING FOR TONIGHT AS MODELS ARE TRENDING TOWARD A DRIER FORECAST. && .PREV DISCUSSION... /ISSUED 326 AM CDT SAT JUL 11 2015/ TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM. 500 MB RIDGE AXIS AND SFC HIGH PRESSURE EXITS THE REGION EARLY SATURDAY MORNING AS A SHORTWAVE TROUGH AND LOW LEVEL WARM AIR ADVECTION ALONG A WARM FRONT MAKES ITS WAY INTO THE REGION. MAINLY HIGH CLOUDS IN THE AREA AHEAD OF THE SHORTWAVE. SOME -SHRA CAN BE SEEN IN SOUTHEAST IOWA AT 08Z SATURDAY...MOVING NORTHEAST AHEAD THE LOW LEVEL BAROCLINIC ZONE. HIGHS SATURDAY LOOK TO BE NEAR 80F ACROSS S WI...AS 925 MB TEMPS ARE PROGGED TO BE NEAR 20C BY THE GFS. 925 MB TEMPERATURES WILL ONLY INCREASE FROM THERE AS WARM FRONT TRANSLATES NORTHEAST. 11.06 HRRR MESO MODEL IS SHOWING THE BULK OF THE PRECIPITATION DURING THE DAY SATURDAY TO BE SOUTH OF THE WI/IL BORDER AS THE HRRR IS PROGGING AN MCV DEVELOPING ACROSS N IL. THIS IS INDICATED IN THE GFS MODEL AS WELL...KEEPING THE STRONGEST MID-LEVEL SUPPORT SOUTH AS ISENTROPIC OMEGA VALUES REACH NEARLY 9 UBAR/S IN THE GFS. SO...REDUCED THE POPS DURING THE DAY SATURDAY. THE BEST CHANCES OF PRECIPITATION WILL BE SATURDAY NIGHT AS THE BEST WARM AIR ADVECTION AND INSTABILITY AXIS REACHES S WI. KEPT LIKELY POPS AS BETTER 850-700 MB FRONTOGENETICAL FORCING AND 850-700 MB Q- VECTOR CONVERGENCE CREEPS INTO THE REGION DURING THIS TIME. THERE IS A MARGINAL RISK FOR SEVERE WEATHER SOUTHWEST OF A JANESVILLE TO CROSS PLAINS TO LOGANVILLE LINE. GOOD INSTABILITY WILL DEVELOP IN THE EVENING AND OVERNIGHT HOURS SATURDAY INTO SUNDAY AS THE LOW LEVEL WAA COMES IN. MOST UNSTABLE CAPE VALUES ARE PROGGED TO REACH 2500+ J/KG ACCORDING TO THE GFS...WHILE THE NAM AND ECMWF ARE SHOWING MUCAPE ONLY AOA 1000 J/KG. SUNDAY - CONFIDENCE...MEDIUM GRADUAL BUILDING OF HEIGHTS WITH ONE SHORTWAVE EXITING THE WESTERN GREAT LAKES REGION. GFS BLOWS UP ANOTHER ONE WITHIN THE BUILDING HEIGHTS REGIME BUT THIS APPEARS TO BE ERRONEOUS WITH OTHER MODELS SHOWING A CLEANER BUILDUP OF THE MID LEVEL RIDGE AXIS. MODELS SHOW SOME LINGERING SHRA/PSBL TSRA PRIOR TO 18Z WITH INFLUENCE OF THE DEPARTING WAVE AND 850/925 BAROCLINICITY. THE 850 FRONT SHIFTS FURTHER NE WITH 925 TEMPS REALLY SOARING THOUGH THE 12Z ECMWF HANGS ONTO THIS BOUNDARY LONGER WHICH SHOWS A COOLER REGIME THAN WHAT THE NAM/GFS IMPLIES. THE GFS SOUNDINGS SHOW CAPES BUILDING UP TO 3000 J/KG WITH INVERSION JUST UNDER 5K FEET. SOME AREAS SEEING SIGNIFICANT CIN DEVELOPING. LIFT BECOMES LESS DISCERNIBLE IN THE AFTERNOON NORTHWARD SHIFT OF WARM FRONT AND ANY UPPER FORCING QUESTIONABLE GIVEN THE PROGGD ERRONEOUS VORT BULLSEYE ON THE GFS. WILL GO WITH TEMPS WELL INTO THE 80S WITH SOME ONSHORE COOLING EFFECTS IN THE EAST. SUNDAY NIGHT INTO MONDAY - CONFIDENCE...MEDIUM EXPECTING AN MCS TO RIDE ALONG LOWER LEVEL BAROCLINICITY LATER SUNDAY NIGHT. UPPER LEVEL JET WILL BE FAVORABLY PLACED WITH LEFT FRONT QUADRANT AND MID LEVEL WAVE RIDING INTO THE UPPER MIDWEST. THE NAM AND GFS SHOW GREATEST WINDOW OF CONCERN BETWEEN 06-12Z. THE 12Z ECMWF WAS SHOWING A SLOWER SOLUTION WITH 12-18Z BEING MORE PRIME. THE LATEST ECMWF SHOWS A LITTLE QUICKER SOLUTION. AIRMASS WILL BE RATHER UNSTABLE THROUGH THE NIGHT. PER SPC DISC FOR SWODY2 THE CONVECTION AFFECTING SRN WI WILL HAVE EVOLVED INTO MORE OF A WIND EVENT AS THESE STORMS RIDE IN NW-SE. CONVECTIVE REDEVELOPMENT WILL HINGE ON HOW BOUNDARIES LAY OUT AFTER THE MORNING STORMS. MID LEVEL FLOW STILL CYCLONIC WITH 250 JET STILL POSITIONED TO OUR SOUTHWEST WITH DIVERGENCE STILL NOTED ACROSS THE AREA. IF AIRMASS CAN RELOAD LOOKING AT CAPE BUILDUP WITH AFTERNOON STORMS ASSOCIATED WITH SURFACE TROUGH...BUT AGAIN LOTS WILL DEPEND ON HOW AIRMASS SETS UP AFTER THE MORNING ACTIVITY. ATTM SPC SWODY3 IS KEYING ON THIS BEING MORE ROBUST FURTHER SOUTH OF OUR CWA PROBABLY MORE CO-LOCATED WITH THE OUTFLOW FROM EARLIER STORMS. TUESDAY - CONFIDENCE...LOW ECMWF/NAM SHOW WEAK SURFACE TROUGH LINGERING WHILE THE GFS SHIFTS BOUNDARY TO OUR SOUTH WITH NE WINDS AND HIGH PRESSURE NOSING IN. SO NEED TO RETAIN SOME POPS FOR THE SLOWER SOLUTIONS WHICH INCLUDES THE NAM AS WELL. ECMWF SHOWS A FAIRLY POTENT WAVE ARRIVINGDURING PRIME TIME AS WELL. HOPEFULLY FUTURE MODEL RUNS WILL COME INTO BETTER AGREEMENT ON THIS. TUESDAY NIGHT AND WEDNESDAY - CONFIDENCE...MEDIUM MODELS SHOW HIGH PRESSURE BUILDING IN WITH NE-E FLOW AND COOLER AIRMASS. THURSDAY AND FRIDAY - CONFIDENCE...LOW THE 00Z ECMWF ESSENTIALLY KEEPS THE INFLUENCE OF THE HIGH IN PLACE THIS PERIOD AS NEXT TROUGH AND ASSOCIATED PRECIP HANGS OUT IN THE PLAINS. THE GFS IS MORE PROGRESSIVE AND SHOWS A MORE ACTIVE PERIOD WITH POTENTIALLY SEVERAL ROUNDS OF PRECIP. GIVEN THE DISPARITY WILL LEAN ON THE SUPERBLEND POPS FOR NOW. AVIATION/12Z TAFS/...VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH SATURDAY MORNING UNTIL LOWER LEVEL CLOUDS AND PERHAPS SOME -SHRA MOVE INTO THE REGION. A MID-LEVEL SHORTWAVE TROUGH WILL SWEEP IN TO THE AREA ALONG WITH A PUSH OF WARMER AIR IN THE 925-850 MB LAYER. BEST CHANCES OF PRECIPITATION WILL BE SATURDAY EVENING AND OVERNIGHT AS BETTER FORCING ARRIVES AT THAT TIME. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...MRC TODAY/TONIGHT AND AVIATION/MARINE...JTS SUNDAY THROUGH FRIDAY...COLLAR
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1147 AM CDT SAT JUL 11 2015 .UPDATE... ISSUED AT 1146 AM CDT SAT JUL 11 2015 HAVE BEEN WORKING THROUGH THE MORNING AT TRYING TO KEEP AHEAD OF THE WEATHER. SHORTWAVE TROUGH ENERGY UPSTREAM MOVING AT THE AREA IS PROVIDING ENOUGH LIFT WITH WEAK WARM ADVECTION AND MINOR MUCAPE /250 J/KG/ OF INSTABILITY TO POP SHOWERS AND ISOLATED THUNDER. BELIEVE THE AREA WILL CONTINUE TO MOVE EAST THROUGH THE DAY AND FEEL SOME DIMINISHMENT MAY OCCUR AS IT DOES. BEHIND THE WAVE...BELIEVE MANY HOURS OF DRY WEATHER WILL HOLD WITH LITTLE FORCING UNTIL AFTER MIDNIGHT. HAVE LOWERED THE RAIN CHANCES BEHIND THE WEATHER UNTIL LATER TONIGHT...BUT AM STILL ASSESSING LATER INTO THE OVERNIGHT. SUBSTANTIAL CLOUD AND RAIN HAS CAUSED TEMPERATURES TO REALLY STAY COOL. HAVE LOWERED HIGHS TODAY SOME...BUT SOME LATE SUN COULD POP THEM UP FAST. SO...HAVE KEPT THE AFTERNOON COOL WITH A LATE JUMP. RAIN RATES ARE PRETTY IMPRESSIVE WITH SUCH LITTLE CAPE. THESE LITTLE SHOWERS ON RADAR ARE CAUSING SOME GOOD DOWNPOURS. 50DBZ CORE NEAR AUTIN MN CAUSED 0.75 INCHES OF RAIN IN A SHORT AMOUNT OF TIME. HERE COMES THE HIGHER PRECIPITABLE WATER WITH 1.5 INCH VALUES TRANSPORTING NORTH OVER THE AREA TODAY. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 339 AM CDT SAT JUL 11 2015 REGIONAL RADARS THIS MORNING SHOWING SOME CONVECTION THIS MORNING OVER NORTHERN MISSOURI WITH ANOTHER AREA OF CONVECTION OVER EASTERN NEBRASKA. THIS ACTIVITY IS NORTH OF A WARM FRONT THAT EXTENDS ACROSS NORTHERN KANSAS AND MISSOURI AND AHEAD OF A WEAK TROUGH OF LOW PRESSURE FROM KANSAS INTO NORTH DAKOTA. WATER VAPOR SATELLITE SHOWS ONE SHORT WAVE TROUGH OVER NEBRASKA AND KANSAS WITH ANOTHER OVER NORTH DAKOTA. THE TREND IN THE 11.00Z MODELS AND 11.03Z RAP IS FOR THE WAVE OVER NEBRASKA AND KANSAS TO FLATTEN OUT AS IT MOVES NORTHEAST INTO THE TOP PART OF THE RIDGE AXIS OVER THE CENTRAL PART OF THE COUNTRY. THE WAVE OVER NORTH DAKOTA WILL ALSO CONTINUE TO MOVE NORTHEAST INTO SOUTHERN CANADA THROUGH THE DAY. THE SURFACE WARM FRONT SHOULD LIFT SLOWLY TO THE NORTH WITH A GENERAL MODEL CONSENSUS OF IT REACHING ABOUT THE IOWA/MISSOURI BORDER. THIS WILL KEEP THE BEST MOISTURE TRANSPORT WELL SOUTH OF THE AREA TODAY AND SHOULD KEEP MOST OF THE RAIN TO THE SOUTH AS WELL. THE MESO MODELS SEEMED TO HAVE LATCHED ON TO THIS AS WELL WITH THE 11.00Z CR-NAM NEST...HI-RES ARW AND NMM KEEPING THE AREA DRY WHILE THE 11.00Z NAM12 AND 11.05Z HRRR STILL TRY TO BRING THE REMAINS OF SOME DEVELOPING CENTRAL IOWA CONVECTION INTO THE SOUTHERN SECTIONS FOR THIS MORNING. BASED ON ALL THESE SOLUTIONS...HAVE TRENDED THE RAIN CHANCES DOWN FOR TODAY WITH ABOUT A 20 PERCENT CHANCE ACROSS THE NORTH TO AT MOST A 40 PERCENT CHANCE IN THE SOUTH. THESE COULD STILL BE TOO HIGH AS IT COULD END UP BEING TOTALLY DRY NORTH OF THE IOWA/MINNESOTA BORDER. UPPER LEVEL HEIGHTS SHOULD BUILD A LITTLE BIT OVER THE REGION TONIGHT AS THE SHORT WAVE TROUGHS MOVE OFF TO THE EAST. THE WARM FRONT WILL CONTINUE TO LIFT SLOWLY NORTH TAKING ON A MORE NORTHWEST TO SOUTHEAST ORIENTATION FROM A DEVELOPING AREA OF LOW PRESSURE OVER NORTH DAKOTA INTO CENTRAL ILLINOIS. THE NAM REALLY RAMPS UP THE MOISTURE TRANSPORT INTO THIS BOUNDARY AROUND 06Z SUNDAY AND BREAKS OUT CONVECTION NORTH OF THE BOUNDARY AND ACROSS THE AREA. THE 11.00Z GFS SOMEWHAT HINTS AT THIS AS WELL WHILE THE 11.00Z ECMWF KEEPS THE BOUNDARY FARTHER SOUTH AND MOST OF THE RAIN TO THE SOUTH AS WELL. THE HI-RES NMM IS SIMILAR TO THE NAM WHILE THE HI-RES ARW IS COMPLETELY DRY FOR TONIGHT. CONCERNED THAT THE NAM IS TOO STRONG WITH THE MOISTURE TRANSPORT TONIGHT AND WILL ONLY CARRY A GENERAL 30 TO 40 PERCENT CHANCE ACROSS THE AREA. THE REAL ACTION AND BEST CHANCES FOR RAIN MAY COME SUNDAY NIGHT. A SHORT WAVE TROUGH IS EXPECTED TO COME OUT OF THE WEAKENING UPPER LEVEL LOW CURRENTLY OVER OREGON AND NEVADA. THIS WAVE SHOULD TOP THE UPPER LEVEL RIDGE AND THEN SLIDE SOUTHEAST ACROSS THE AREA SUNDAY NIGHT. THE GFS SUGGESTS THIS WAVE WILL PRODUCE SOME MODERATE PV ADVECTION IN THE 500-300 MB LAYER AS IT COMES ACROSS. THIS LIFT SHOULD BE AIDED BY SOME JET DYNAMICS FROM THE LEFT EXIT REGION OF THE 300 MB JET AS THIS COMES IN WITH THE SHORT WAVE TROUGH. THE WARM FRONT SHOULD CONTINUE TO EDGE NORTH EXTENDING FROM EASTERN NORTH DAKOTA INTO ILLINOIS WITH THE GFS SHOWING WEAK TO MODERATE FRONTOGENESIS IN THE 1000-850 MB LAYER NORTH OF THE FRONT. AS THE SHORT WAVE TROUGH APPROACHES...A CONVECTIVE COMPLEX SHOULD FROM LATE SUNDAY AFTERNOON OVER THE EASTERN DAKOTAS AND THEN SLIDE SOUTHEAST THROUGH THE NIGHT ALONG AND NORTH OF THE WARM FRONT. THERE SHOULD STILL BE AMPLE CAPE AVAILABLE FOR THE STORMS TO WORK WITH AS THEY MOVE INTO THE AREA. THE GFS SUGGESTS UP TO 2500 J/KG OF ML CAPE SUNDAY EVENING ONLY DROPPING OFF TO 1500 J/KG DURING THE OVERNIGHT HOURS. UP TO 40 KNOTS OF SHEAR SHOULD MOVE IN AHEAD OF THE SHORT WAVE TROUGH WITH THIS BEING PRIMARILY IN THE 0-3 KM LAYER. THIS WILL PRESENT THE OPPORTUNITY FOR A NOCTURNAL MCS TO ROLL ACROSS THE AREA WITH A SEVERE WIND THREAT. HAIL DOES NOT LOOK TO BE MUCH OF THREAT WITH WARM CLOUD DEPTHS ON THE ORDER OF 3.5 TO 4 KM...BUT THERE SHOULD BE SOME GOOD RAINFALL RATES AND LOCALLY HEAVY RAINS. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 339 AM CDT SAT JUL 11 2015 THE UPPER LEVEL RIDGE SHOULD BRIEFLY BUILD BACK OVER THE REGION EARLY IN THE WEEK BEFORE FLATTENING OUT WITH ZONAL FLOW OVER THE UPPER MIDWEST. THIS PATTERN LOOKS TO BE A DIRTY FLOW WITH THE POTENTIAL FOR SEVERAL SHORT WAVE TROUGHS TO BE EMBEDDED IN THE FLOW AND COME ACROSS THE REGION. DECENT AGREEMENT IN TIMING OF A WAVE FOR WEDNESDAY BETWEEN THE ECMWF AND GFS...BUT DIFFERENCES IN STRENGTH WITH THE GFS BEING STRONGER. AFTER THAT...CONSIDERABLE DIFFERENCES IN HOW AN UPPER LEVEL LOW COMING ACROSS SOUTHWEST CANADA IS HANDLED. THE GFS OPENS THIS SYSTEM UP AND BRINGS IT TOWARD THE AREA BY THE END OF THE WEEK WHILE THE ECMWF KEEPS IT AS A CLOSED LOW HOLDING IT BACK WITH RIDGING OVER THE REGION. WITH ALL THE UNCERTAINTY...WILL STAY WITH GENERAL 20 TO 40 PERCENT CHANCES THROUGH THE PERIOD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 622 AM CDT SAT JUL 11 2015 A GENERALLY VFR PERIOD EXPECTED TODAY/TONIGHT. INCREASING MOISTURE DOES LOOK TO SPREAD 3500-4500 FT BKN CIGS ACROSS THE AREA LATE THIS MORNING INTO EARLY THIS EVENING...WITH THESE CLOUDS/MOISTURE SPREADING NORTHWARD ACROSS IA EARLY THIS MORNING. SOME DRYING OF THE LOWER PORTION OF THE COLUMN TONIGHT...WITH MORE SCT CUMULUS/STRATO- CUMULUS EXPECTED AFTER 01-02Z. SHRA/TSRA CHANCES AT THE TAF SITES MORE IN QUESTION THIS AFTERNOON THRU TONIGHT. GIVEN EXPECTED WIDELY SCT TO SCT COVERAGE OF ANY SHRA/TSRA THIS AFTERNOON/TONIGHT...AND LOWER CONFIDENCE IN THE TIMING OF ANY PERIODS WHEN SHRA/TSRA WOULD BE MORE LIKELY TO OCCUR...CONTINUED THE TREND OF LEAVING VCSH/VCTS OUT OF THE TAFS FOR NOW. IF DETAILS BECOME CLEARER ON SHRA/TSRA OCCURRENCE NEAR/AT KLSE/KRST LATER CYCLES MAY BE ABLE TO MENTION OF SUCH TO THE TAFS AS NEEDED. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...BAUMGARDT SHORT TERM...04 LONG TERM....04 AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
352 PM MDT SAT JUL 11 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 328 PM MDT SAT JUL 11 2015 ISOLATED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ARE CURRENTLY DEVELOPING ALONG THE I80 CORRIDOR IN SOUTHEAST WYO. EXPECT THAT SOME OF THIS ACTIVITY WILL SPREAD EASTWARD INTO THE SOUTHERN PANHANDLE IN THE NEXT FEW HOURS WITH LINGERING OUTFLOW BOUNDARIES FROM CONVECTION EARLIER THIS AM. LLVL MOISTURE IS MODEST...BUT DEW POINTS IN THE 40S ARE CONTRIBUTING TO SBCAPES AROUND 500-1000 J/KG PER THE LATEST MESO ANALYSIS FROM SPC. WILL MAINTAIN SLIGHT CHANCE POPS THROUGH 03Z...AT WHICH POINT THE HRRR HAS CONSISTENTLY SHUT THINGS OFF. DO NOT EXPECT TO SEE ANYTHING SEVERE TODAY WITH WEAK VERTICAL SHEAR...BUT SOME OF THE STORMS COULD PRODUCE GUSTY WINDS WITH INVERTED-V TYPE SOUNDINGS IN THE DRIER SFC ENVIRONMENT ALONG/WEST OF THE LARAMIE RANGE. SUNDAY APPEARS TO BE THE MOST LIKELY DAY TO BE FREE OF ANY SHOWER OR THUNDERSTORM ACTIVITY OUTSIDE OF THE MOUNTAINS. SEVERAL WEAK MIDLVL DISTURBANCES WILL TRAVERSE THE FLOW...BUT H7-H3 MOISTURE PROGS FROM THE GFS/NAM/ECM ARE CONSIDERABLY DRIER THAN TODAY IN ADVANCE OF AN APPROACHING SHORTWAVE RIDGE. THE MODELS ARE GENERALLY DRY...EXCEPT THE ECMWF WHICH PAINTS SOME LIGHT QPF SPREADING OVER THE PLAINS IN THE 18Z-00Z TIME FRAME. GUIDANCE HAS HAD A TOUGH TIME RECENTLY WITH THE MOIST LLVL ENVIRONMENT AND SMALL-SCALE FORCING MECHANISMS...SO HONESTLY WOULD NOT BE SURPRISED IF LATER SHIFTS NEED TO MENTION THE POSSIBILITY OF A TSTM OR TWO ON THE PLAINS IN THE LATE AFTN. IT WILL BE MUCH WARMER ALOFT THOUGH...SO CAPPING WILL PLAY A ROLE. SHOULD BE QUITE WARM TOMORROW WITH H7 TEMPS +14 TO +16 C. .LONG TERM...(TUESDAY THROUGH SATURDAY) ISSUED AT 348 PM MDT SAT JUL 11 2015 CHANCES FOR SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH MUCH OF NEXT WEEK BUT THERE WILL BE SOME CHANGES TO THE OVERALL WEATHER PATTERN. UPPER LEVEL RIDGE AXIS WILL SHIFT INTO THE PLAINS WITH SOUTHWEST FLOW OVER THE CENTRAL ROCKIES EARLY NEXT WEEK. RELATIVELY MOIST SOUTHWEST FLOW WILL PUMP MOISTURE ALONG WITH CHANCES FOR SHOWERS AND THUNDERSTORMS INTO THE FORECAST AREA. TOUGH TO PINPOINT WHEN THE MAIN CHANCES FOR PRECIPITATION WILL OCCUR GIVEN THAT SMALL DISTURBANCE EMBEDDED IN SOUTHWEST FLOW WILL BE THE MAIN TRIGGERS FOR PRECIPITATION. TIMING OF THESE SUBTLE DISTURBANCES IS VERY DIFFICULT FOR THE NUMERICAL MODELS TO DETERMINE WITH GREAT ACCURACY. BY MID NEXT WEEK THE RIDGE LOOKS TO FLATTEN WITH ZONAL FLOW OVER THE WESTERN CONUS. SEVERAL EMBEDDED DISTURBANCES WILL CONTINUE TO MOVE OVER THE AREA BRINGING MORE CHANCES FOR SHOWERS AND THUNDERSTORMS. LATE IN THE WEEK BOTH THE ECMWF AND GFS ARE SHOWING AN UNSEASONABLY STRONG TROUGH DIGGING INTO THE PACIFIC NORTHWEST. THIS TROUGH MAY IMPACT THE FORECAST AREA BY NEXT WEEKEND... BRINGING CONTINUED CHANCES FOR PRECIPITATION AND THE POTENTIAL FOR A VERY COOL SHOT OF AIR FOR MID JULY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1156 AM MDT SAT JUL 11 2015 ISOLATED THUNDERSTORMS WILL MOVE ACROSS PORTIONS OF SOUTHEAST WYOMING THIS AFTERNOON/EARLY EVENING WITH A FEW THUNDERSTORMS ALSO POSSIBLE INTO THE NEBRAKSA PANHANDLE. ERRATIC GUSTY WINDS WILL BE THE MAIN AVIATION THREAT IN THE VICINITY OF THESE STORMS. THUNDERSTORM ACTIVITY WILL RAPIDLY DECREASE THROUGH THE EVENING HOURS. && .FIRE WEATHER... ISSUED AT 313 PM MDT SAT JUL 11 2015 ISOLATED SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE THROUGH THE LATE AFTN AND EARLY EVE HOURS. THE PRIMARY HAZARD FROM THIS ACTIVITY WILL BE GUSTY AND ERRATIC WIND GUSTS. WARMER CONDITIONS ARE EXPECTED FOR SUNDAY WITH MINIMUM HUMIDITY VALUES AROUND 20 PERCENT. THE NEXT CHANCE FOR MORE WIDESPREAD PRECIPITATION WILL ARRIVE LATE MON INTO TUE. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...CLH LONG TERM...SML AVIATION...SML FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1200 PM MDT SAT JUL 11 2015 .UPDATE... ISSUED AT 1006 AM MDT SAT JUL 11 2015 MINOR UPDATE TO ADD LOW-END POPS ACROSS SOUTHEAST WY AND THE SOUTHERN NEB PANHANDLE THIS AFTN/EVE. THE MAJORITY OF GUIDANCE SUGGESTS DRY CONDITIONS OUTSIDE OF THE MOUNTAINS...BUT THERE IS STILL DECENT LLVL MOISTURE WITH DEWPOINTS IN THE 45 TO 55 DEGREE RANGE. INSTABILITY WILL BE PRESENT AS WELL WITH THE NAM SHOWING CAPE VALUES AROUND 1000 J/KG. WEAK DISTURBANCES EMBEDDED WITHIN MOIST SOUTHWESTERLY FLOW ALOFT...COMBINED WITH LLVL FORCING ALONG RESIDUAL BOUNDARIES FROM MORNING CONVECTION MAY RESULT IN ISOLATED TO WIDELY SCATTERED SHOWERS/TSTMS OVER THE PLAINS. RECENT RUNS OF THE HRRR WOULD SUGGEST THIS AS WELL. UPDATES HAVE BEEN SENT. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 300 AM MDT SAT JUL 11 2015 SHOWERS AND T-STORMS DEVELOPED EARLIER TONIGHT IN NORTHEAST COLORADO AND SPREAD ACROSS EXTREME SOUTHEAST WYOMING AND THE WESTERN NEBRASKA PANHANDLE. SUSPECT THIS ACTIVITY INITIATED ALONG A MID LEVEL BOUNDARY SITUATED WEST-EAST NEAR THE TRI-STATE BORDER AND WAS SUPPORTED BY ELEVATED INSTABILITY AND WEAK VORTICITY MOVING OVERHEAD. SHOULD SEE THIS ACTIVITY DISSIPATE BY SUNRISE AS IT MOVES OFF TO THE EAST WITH THE REMAINDER OF THE MORNING REMAINING MOSTLY DRY. TODAY WILL FEATURE A STRENGTHENING SOUTHWEST JET OVER THE GREAT BASIN AND CENTRAL ROCKIES WITH PACIFIC MOISTURE AND SEVERAL WEAK DISTURBANCES MOVING OVER THE CWA. IT SEEMS MORE LIKELY WE WILL HAVE SHOWERS AND STORMS DEVELOP OVER THE MOUNTAINS THIS AFTERNOON AND SHIFT OFF TO THE EAST-NORTHEAST IN THE LATE AFTERNOON AND PERHAPS THE EVENING. TEMPS AT H7 WILL INCREASE TO 13-14C BY 00Z THO WHICH SHOULD MINIMIZE CONVECTIVE POTENTIAL FURTHER EAST AWAY FROM THE MOUNTAINS. SO MAINTAINED FOCUS FOR POPS IN THE MOUNTAINS AND NEARBY LOWER ELEVATIONS...WITH AN ISOLATED COVERAGE FOR STORMS ANTICIPATED DUE TO OVERALL LOW INSTABILITY. SUNDAY EXHIBITS A FAIR AMOUNT OF UNCERTAINTY REGARDING T-STORM POTENTIAL. LOOKING AT GOOD UPPER LEVEL SUPPORT FROM A 100 KT JET WHILE A SHORTWAVE TROUGH MOVES OVERHEAD IN THE AFTERNOON. BREEZY WESTERLY WINDS ARE ANTICIPATED AT THE SFC THO...LEAVING LITTLE IN TERMS OF SFC FORCING OTHER THAN GENERAL OROGRAPHICS. ALSO...MODELS SHOW A DRY PUNCH ADVECTING OVERHEAD IN THE AFTERNOON WHICH IS NOT FAVORABLE FOR CONVECTIVE DEVELOPMENT SO KEPT CONDITIONS MOSTLY DRY EXCEPT FOR A FEW MOUNTAINS STORMS. MONSOONAL MOISTURE WILL VISIT THE CENTRAL ROCKIES ON MONDAY SO EXPECT TYPICAL HIGH BASED STORMS TO OCCUR OVER THE MOUNTAINS AND NEARBY HIGH VALLEYS. WEAK WESTERLY SFC WINDS LOOK TO REMAIN IN PLACE ACROSS THE PLAINS...SO NOT ANTICIPATING MUCH ACTIVITY OVER THIS AREA EXCEPT PERHAPS A STRAY SHOWER THAT CAN SURVIVE OFF THE MOUNTAINS. TEMPERATURES THROUGH THE WEEKEND WILL REMAIN QUITE WARM WITH THE HOTTEST DAY ON SUNDAY WITH MID 80-90S ACROSS THE EAST AND 70S-80S IN THE HIGH COUNTRY. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 300 AM MDT SAT JUL 11 2015 WITH SOUTHWESTERLY FLOW ALOFT IN PLACE ON TUES...BOTH THE GFS AND ECMWF INDICATE AN INCREASE IN MONSOONAL MOISTURE AS 700-500MB RH VALUES COME UP. THUS WILL SEE AN INCREASE IN AFTN AND EVENING CONVECTION ON TUES. WILL FCST ISOLATED TO SCATTERED COVERAGE OF STORMS FOR NOW. STRONG STORMS DO NOT APPEAR LIKELY WITH RATHER LIMITED INSTABILITY/SHEAR. THE GFS DOES SHOW SOME DRYING BY WED WHEREAS THE ECMWF KEEPS THE MIDLVL MOISTURE PLUME OVERHEAD FOR ONE MORE DAY. AN UPPER TROUGH IS PROGGED TO AMPLIFY INTO THE NORTHERN ROCKIES BY THURS WITH FLOW ALOFT BECOMING MORE WESTERLY ACROSS WYOMING...BRINGING IN SOME DRYING AND REDUCED CHANCES FOR TSTMS. COULD SEE A COLD FRONTAL PASSAGE BY THURS NIGHT/FRI MORNING AS THE TROUGH PROGRESSES EASTWARD OVER MONTANA. TEMPS THROUGH THE EXTENDED WILL BE AROUND NORMAL FOR MID JULY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1156 AM MDT SAT JUL 11 2015 ISOLATED THUNDERSTORMS WILL MOVE ACROSS PORTIONS OF SOUTHEAST WYOMING THIS AFTERNOON/EARLY EVENING WITH A FEW THUNDERSTORMS ALSO POSSIBLE INTO THE NEBRAKSA PANHANDLE. ERRATIC GUSTY WINDS WILL BE THE MAIN AVIATION THREAT IN THE VICINITY OF THESE STORMS. THUNDERSTORM ACTIVITY WILL RAPIDLY DECREASE THROUGH THE EVENING HOURS. && .FIRE WEATHER... ISSUED AT 300 AM MDT SAT JUL 11 2015 ISOLATED SHOWERS AND THUNDERSTORMS ARE POSSIBLE MAINLY DURING THE AFTERNOON HOURS THIS WEEKEND WITH THE FOCUS FOR ACTIVITY OVER THE MOUNTAINS. WESTERLY WINDS WILL BE BREEZY OVER MUCH OF THE DISTRICT BUT AFTERNOON HUMIDITIES SHOULD REMAIN IN THE UPPER TEENS TO UPPER 20S. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...CLH SHORT TERM...RJM LONG TERM...ZF AVIATION...SML FIRE WEATHER...RJM
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1014 AM MDT SAT JUL 11 2015 .UPDATE... ISSUED AT 1006 AM MDT SAT JUL 11 2015 MINOR UPDATE TO ADD LOW-END POPS ACROSS SOUTHEAST WY AND THE SOUTHERN NEB PANHANDLE THIS AFTN/EVE. THE MAJORITY OF GUIDANCE SUGGESTS DRY CONDITIONS OUTSIDE OF THE MOUNTAINS...BUT THERE IS STILL DECENT LLVL MOISTURE WITH DEWPOINTS IN THE 45 TO 55 DEGREE RANGE. INSTABILITY WILL BE PRESENT AS WELL WITH THE NAM SHOWING CAPE VALUES AROUND 1000 J/KG. WEAK DISTURBANCES EMBEDDED WITHIN MOIST SOUTHWESTERLY FLOW ALOFT...COMBINED WITH LLVL FORCING ALONG RESIDUAL BOUNDARIES FROM MORNING CONVECTION MAY RESULT IN ISOLATED TO WIDELY SCATTERED SHOWERS/TSTMS OVER THE PLAINS. RECENT RUNS OF THE HRRR WOULD SUGGEST THIS AS WELL. UPDATES HAVE BEEN SENT. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 300 AM MDT SAT JUL 11 2015 SHOWERS AND T-STORMS DEVELOPED EARLIER TONIGHT IN NORTHEAST COLORADO AND SPREAD ACROSS EXTREME SOUTHEAST WYOMING AND THE WESTERN NEBRASKA PANHANDLE. SUSPECT THIS ACTIVITY INITIATED ALONG A MID LEVEL BOUNDARY SITUATED WEST-EAST NEAR THE TRI-STATE BORDER AND WAS SUPPORTED BY ELEVATED INSTABILITY AND WEAK VORTICITY MOVING OVERHEAD. SHOULD SEE THIS ACTIVITY DISSIPATE BY SUNRISE AS IT MOVES OFF TO THE EAST WITH THE REMAINDER OF THE MORNING REMAINING MOSTLY DRY. TODAY WILL FEATURE A STRENGTHENING SOUTHWEST JET OVER THE GREAT BASIN AND CENTRAL ROCKIES WITH PACIFIC MOISTURE AND SEVERAL WEAK DISTURBANCES MOVING OVER THE CWA. IT SEEMS MORE LIKELY WE WILL HAVE SHOWERS AND STORMS DEVELOP OVER THE MOUNTAINS THIS AFTERNOON AND SHIFT OFF TO THE EAST-NORTHEAST IN THE LATE AFTERNOON AND PERHAPS THE EVENING. TEMPS AT H7 WILL INCREASE TO 13-14C BY 00Z THO WHICH SHOULD MINIMIZE CONVECTIVE POTENTIAL FURTHER EAST AWAY FROM THE MOUNTAINS. SO MAINTAINED FOCUS FOR POPS IN THE MOUNTAINS AND NEARBY LOWER ELEVATIONS...WITH AN ISOLATED COVERAGE FOR STORMS ANTICIPATED DUE TO OVERALL LOW INSTABILITY. SUNDAY EXHIBITS A FAIR AMOUNT OF UNCERTAINTY REGARDING T-STORM POTENTIAL. LOOKING AT GOOD UPPER LEVEL SUPPORT FROM A 100 KT JET WHILE A SHORTWAVE TROUGH MOVES OVERHEAD IN THE AFTERNOON. BREEZY WESTERLY WINDS ARE ANTICIPATED AT THE SFC THO...LEAVING LITTLE IN TERMS OF SFC FORCING OTHER THAN GENERAL OROGRAPHICS. ALSO...MODELS SHOW A DRY PUNCH ADVECTING OVERHEAD IN THE AFTERNOON WHICH IS NOT FAVORABLE FOR CONVECTIVE DEVELOPMENT SO KEPT CONDITIONS MOSTLY DRY EXCEPT FOR A FEW MOUNTAINS STORMS. MONSOONAL MOISTURE WILL VISIT THE CENTRAL ROCKIES ON MONDAY SO EXPECT TYPICAL HIGH BASED STORMS TO OCCUR OVER THE MOUNTAINS AND NEARBY HIGH VALLEYS. WEAK WESTERLY SFC WINDS LOOK TO REMAIN IN PLACE ACROSS THE PLAINS...SO NOT ANTICIPATING MUCH ACTIVITY OVER THIS AREA EXCEPT PERHAPS A STRAY SHOWER THAT CAN SURVIVE OFF THE MOUNTAINS. TEMPERATURES THROUGH THE WEEKEND WILL REMAIN QUITE WARM WITH THE HOTTEST DAY ON SUNDAY WITH MID 80-90S ACROSS THE EAST AND 70S-80S IN THE HIGH COUNTRY. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 300 AM MDT SAT JUL 11 2015 WITH SOUTHWESTERLY FLOW ALOFT IN PLACE ON TUES...BOTH THE GFS AND ECMWF INDICATE AN INCREASE IN MONSOONAL MOISTURE AS 700-500MB RH VALUES COME UP. THUS WILL SEE AN INCREASE IN AFTN AND EVENING CONVECTION ON TUES. WILL FCST ISOLATED TO SCATTERED COVERAGE OF STORMS FOR NOW. STRONG STORMS DO NOT APPEAR LIKELY WITH RATHER LIMITED INSTABILITY/SHEAR. THE GFS DOES SHOW SOME DRYING BY WED WHEREAS THE ECMWF KEEPS THE MIDLVL MOISTURE PLUME OVERHEAD FOR ONE MORE DAY. AN UPPER TROUGH IS PROGGED TO AMPLIFY INTO THE NORTHERN ROCKIES BY THURS WITH FLOW ALOFT BECOMING MORE WESTERLY ACROSS WYOMING...BRINGING IN SOME DRYING AND REDUCED CHANCES FOR TSTMS. COULD SEE A COLD FRONTAL PASSAGE BY THURS NIGHT/FRI MORNING AS THE TROUGH PROGRESSES EASTWARD OVER MONTANA. TEMPS THROUGH THE EXTENDED WILL BE AROUND NORMAL FOR MID JULY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 549 AM MDT SAT JUL 11 2015 VFR CONDITIONS THROUGH THE TAF PERIOD. RAIN SHOWERS ARE EXPECTED TO CONTINUE AT SNY OVER THE NEXT FEW HOURS BEFORE TAPERING OFF. CUMULUS WILL DEVELOP BY EARLY AFTERNOON...HOWEVER THE CHANCE OF TSTMS IS QUITE SMALL SO WILL KEEP OUT OF THE TAF. SOUTHWEST WINDS WILL GUST TO 20-30 KTS TO THE WEST OF THE LARAMIE RANGE DURING THE AFTERNOON. && .FIRE WEATHER... ISSUED AT 300 AM MDT SAT JUL 11 2015 ISOLATED SHOWERS AND THUNDERSTORMS ARE POSSIBLE MAINLY DURING THE AFTERNOON HOURS THIS WEEKEND WITH THE FOCUS FOR ACTIVITY OVER THE MOUNTAINS. WESTERLY WINDS WILL BE BREEZY OVER MUCH OF THE DISTRICT BUT AFTERNOON HUMIDITIES SHOULD REMAIN IN THE UPPER TEENS TO UPPER 20S. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...CLH SHORT TERM...RJM LONG TERM...ZF AVIATION...ZF FIRE WEATHER...RJM