Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 09/21/15


AREA FORECAST DISCUSSION
NWS PHOENIX AZ
746 PM MST SUN SEP 20 2015 .SYNOPSIS... ANOMALOUSLY HIGH MOISTURE WILL MOVE INTO THE AREA EARLY MONDAY MORNING AS TROPICAL MOISTURE IS DRAWN INTO THE DESERT SOUTHWEST. THIS WILL RESULT IN AN ELEVATED CHANCE OF SHOWERS AND THUNDERSTORMS ALONG WITH HEAVY RAINFALL. AREAS OF HEAVY RAINFALL ARE ALSO FORECAST AND A FLASH FLOOD WATCH IS IN EFFECT UNTIL TUESDAY AFTERNOON. CONDITIONS WILL DRY OUT LATE IN THE WEEK INTO THE WEEKEND. && .DISCUSSION... NOTE: THE POTENTIAL FOR EXCESSIVE RAINFALL IS STILL FORECAST FOR OUR AREA...SOUTHEAST CA TO SOUTH CENTRAL AZ MONDAY AND TUESDAY. A FLASH FLOOD WATCH IS POSTED. DETAILS BELOW. HIGH CLOUDS ASSOCIATED WITH TROPICAL DEPRESSION 16-E HAVE BEEN SLOWLY MOVING INTO THE DESERT SOUTHWEST SINCE THIS AFTERNOON AND HAVE ALMOST COMPLETELY OVERSPREAD THE AREA AS OF 02Z. QUITE A BIT OF CONVECTION HAS DEVELOPED OVER THE GULF OF CALIFORNIA NEAR THE CIRCULATION CENTER /CLOUD TOPS HAVE COOLED CONSIDERABLY AND IN-CLOUD LIGHTNING HAS JUMPED SUBSTANTIALLY SINCE 00Z/. MOST OF THE MOISTURE ASSOCIATED WITH THIS SYSTEM HAS BEEN CONFINED TO THE UPPER LEVELS THUS FAR ACROSS SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA /SFC DEWPOINTS STILL IN THE MID 50S AND 00Z SOUNDINGS ONLY SHOWING SATURATION AROUND 300MB/. HOWEVER...THE FIRST REFLECTION OF INCREASED SURFACE MOISTURE IS BECOMING APPARENT AT YUMA AS WINDS HAVE TURNED AROUND OUT OF THE SOUTH AND KYUX RADAR IS SHOWING ENHANCED INBOUND VELOCITIES FROM THE GULF OF CALIFORNIA. DEWPOINTS HAVE TAKEN A BIT OF A JUMP AND THIS TREND HAS BEEN CAPTURED WELL BY THE PREVIOUS FEW RUNS OF THE HRRR AND IS FORECAST TO CONTINUE WELL INTO THE OVERNIGHT HOURS. BIG-PICTURE OUTLOOK REMAINS LARGELY UNCHANGED AS ANOMALOUSLY HIGH MOISTURE /WELL INTO THE 99TH PERCENTILE FOR MID-LATE SEPTEMBER/ IS EXPECTED TO OVERSPREAD THE ENTIRE AREA BY MONDAY AFTERNOON. LATEST AVAILABLE 00Z DETERMINISTIC GUIDANCE ALONG WITH 12Z PROBABILISTIC DATASETS APPEAR TO FOCUS THE HIGHEST RAINFALL CHANCES /AND AMOUNTS/ IN THE 00Z-12Z TUESDAY TIME PERIOD. AS THIS IS ALREADY REFLECTED WELL IN THE INHERITED FORECASTS...NO SIGNIFICANT CHANGES ARE NECESSARY. COULD SEE SOME ISOLATED SHOWERS DEVELOP ACROSS THE AREA LATE THIS EVENING/EARLY MONDAY MORNING ALONG THE LEADING EDGE OF THE MOISTURE GRADIENT BUT THE HEAVIER/MORE WIDESPREAD RAINFALL IS STILL SEVERAL HOURS AWAY. FOR THIS EVENING...SIMPLY MAKING NEAR-TERM ADJUSTMENTS BASED ON OBSERVATIONAL TRENDS. && .PREVIOUS DISCUSSION... MONDAY AND TUESDAY... THE POTENTIAL FOR HEAVY TROPICAL TYPE RAINFALL IS COMING INTO BETTER FOCUS. MANY ATMOSPHERIC PARAMETERS WILL COME TOGETHER FOR 3 SOURCES OR MECHANISMS FOR RAIN. 1...A LARGE AND FAIRLY STRONG PACIFIC TROF LOCATED ABOUT 400 MILES SOUTHWEST OF SAN DIEGO WILL BEGIN TO MOVE TOWARD THE SAN DIEGO COAST TONIGHT. STRENGTHENING CYCLONIC WINDS WILL HELP TO DRAW A TROPICAL FEATURE NORTHWARD...WHICH RESEMBLES A TROPICAL DEPRESSION...FROM JUST OFF THE CENTRAL BAJA COAST THIS AFTERNOON TO JUST SOUTHEAST OF YUMA BY LATE MONDAY MORNING. THIS FEATURE IS DYNAMIC. IT CONTAINS 20 TO 40 KNOT 850/700 MB SOUTH/ SOUTHEAST WINDS...REPLETE WITH STRONG MOISTURE CONVERGENCE AND TROPICAL WARM LOW LEVEL RAINFALL...INCLUDING ENHANCE UPSLOPE RAIN OVER THE SMALLER MTNS OF SOUTHERN AZ. 2...GENERAL RAINFALL IS ALSO EXPECTED FROM MID/UPPER LEVEL DYNAMICAL SUPPORT. AND 3... THUNDER- STORM RAIN. IN FACT MOISTURE CONVERGENCE IS SO STRONG THAT MODELED SOUNDINGS FORECAST CONVECTIVE TRIGGER TEMPERATURES IN THE LOW TO MID 80S IN SOUTHWEST AZ MONDAY. THE LOW LEVEL TROPICAL LIKE CIRCULATION CENTER OF 15 TO 30 KNOT 850/700 MB WINDS...AND MOISTURE CONVERGENCE...IS FORECAST TO MOVE FROM A POSITION 100 MILES WEST OF TUCSON LATE MONDAY AFTERNOON...TO NEAR PHOENIX BY 11 PM MON. THEREFORE THE BULK OF THE UPSLOPE WARM RAIN SHOULD FALL BETWEEN PHOENIX AND GLOBE MIAMI...BUT MORE FOCUSED IN SOUTHERN GILA COUNTY WHERE UP TO 3 INCHES STORM TOTAL PRECIP IS EXPECTED. TUESDAY... THE BULK OF THE TROPICAL MOISTURE MOVES OUT OF THE AREA. HOWEVER...WITH VERY HIGH BOUNDARY LAYER MOISTURE DEPOSITED BY ANTECEDENT RAIN...AND A DYNAMICAL PACIFIC LOW PRESSURE SYSTEM FORECAST TO MOVE ACROSS SOUTHERN CA/WESTERN AZ BY LATE TUESDAY AFTERNOON...CONVECTIVE RAINS ARE FORECAST. UNI-DIRECTIONAL SHEAR WILL RESULT IN FAST MOVING THUNDERSTORMS AND THE POSSIBILITY OF STRONG WET DOWNBURST WINDS...HEAVY RAIN...AND HAIL...MAINLY OVER PORTIONS OF SOUTH CENTRAL AZ INCLUDING PHOENIX. WEDNESDAY... STARTING AFTER MIDNIGHT TUESDAY NIGHT THROUGH WEDNESDAY NIGHT THERE WILL BE A MARKED CLEARING AND DRYING TREND FROM THE WEST AS THE UPPER LOW QUICKLY MOVES OFF TO THE NORTHEAST AND DRIER SOUTHWEST FLOW ALOFT STARTS TO SPREAD INTO THE AREA FROM THE WEST. POPS WILL LOWER INTO THE SLIGHT CHANCE CATEGORY MOST PLACES BY WEDNESDAY AFTERNOON. HIGH TEMPS WEDNESDAY WILL RISE A FEW DEGREES BUT REMAIN WELL BELOW SEASONAL NORMALS. THURSDAY INTO SATURDAY... DRY WITH A WARMING TREND IS EXPECTED AREA WIDE AS HIGHER PRESSURE BUILDS ACROSS THE AREA. AS H5 HEIGHTS RISE ABOVE 590DM HIGH TEMPS SHOULD AGAIN REACH INTO THE UPPER 90S TO LOW TRIPLE DIGITS OVER THE WARMER LOWER DESERTS. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... CLOUDS WILL GRADUALLY THICKEN AND LOWER AT ALL TERMINALS. RAIN IS LIKELY TO ARRIVE ACROSS SOUTHEAST CALIFORNIA FIRST /LIKELY IN THE 16Z-20Z TIME FRAME/...THEN GRADUALLY SPREAD INTO THE PHOENIX AREA CLOSER TO 21Z-00Z. CIGS ARE EXPECTED TO FALL TO 7-8KFT AREA-WIDE BUT LOWER VALUES WILL BE POSSIBLE WITHIN ANY STRONGER SHOWERS/STORMS. CONDITIONS ARE LIKELY TO BE AT THEIR WORST MONDAY EVENING INTO EARLY TUESDAY MORNING. AS FOR WINDS...EXPECTING TYPICAL DIURNAL HEADINGS THROUGH LATE MONDAY. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... WEDNESDAY THROUGH SUNDAY... WILL SEE CONDITIONS BEGIN TO DRY OUT STARTING LATER WEDNESDAY AND CONTINUE THE DRYING TREND INTO THE WEEKEND. HUMIDITIES WILL TREND DOWNWARD STARTING WEDNESDAY WITH AFTERNOON MINIMUM READINGS INTO THE 20-25 PERCENT RANGE BY LATE IN THE WEEK. WINDS WILL TEND TO BE LIGHT ON THE LIGHT SIDE THROUGH THE ENTIRE PERIOD WHILE TEMPERATURES GET A BOOST AND REACHING NEAR SEASONAL NORMALS BY THURSDAY. && .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING PROCEDURE. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...FLASH FLOOD WATCH FROM 5 AM MST MONDAY THROUGH TUESDAY AFTERNOON FOR AZZ020>028. CA...FLASH FLOOD WATCH FROM 5 AM PDT MONDAY THROUGH TUESDAY AFTERNOON FOR CAZ030>033. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...LEINS/VASQUEZ/CB AVIATION...LEINS FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
234 PM MDT SAT SEP 19 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 231 PM MDT SAT SEP 19 2015 A SHORTWAVE TROF WL BE MOVING ACRS THE AREA TONIGHT AND INTO EARLY SUN. THE NAM SHOWS SOME ISOLD PCPN DEVELOPING LATER TODAY OVER SOME OF THE MTNS AND THEN SPREADING EAST TONIGHT ACRS THE PLAINS. THE LATEST HRRR IS DRY THRU ABOUT 00Z AND THEN IT SHOWS SOME ISOLD PCPN DEVELOPING OVR THE ERN PLAINS WHICH THEN EXITS THE STATE AROUND 07Z. MEASURABLE PCPN CHANCES LOOK QUITE LOW TONIGHT SO WL KEEP POPS MINIMAL. OVER NIGHT LOW TEMPS TONIGHT WL BE IN THE 40S TO LOWER 50S ACRS THE PLAINS...WITH 30S TO LOWER 40S OVER THE HIGH VALLEYS. ALAMOSA AND SURROUNDING LOCATIONS SHOULD HAVE LOWS IN THE LOWER TO MID 30S. ON SUN AN UPR RIDGE WL START BUILDING BACK OVR THE AREA...BUT A WEAK SHORTWAVE WL BRUSH NE AND E CENTRAL CO IN THE AFTERNOON. AT THIS TIME IT LOOKS LIKE DRY WEATHER CAN BE EXPECTED ACRS THE FORECAST AREA ON SUN...WITH HIGH TEMPS BEING WARMER THAN TODAY AND AROUND 5 DEGREES ABOVE NORMAL. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 231 PM MDT SAT SEP 19 2015 ...DRY AND WARM THROUGH THE EXTENDED PERIOD... LOOKS LIKE THE DRY AND WARM WEATHER THAT HAS DEFINED SEPTEMBER IN SE CO IS HERE TO STAY...AT LEAST THROUGH THE END OF NEXT WEEK. MONDAY...SHOULD BE THE WARMEST DAY OF THE WEEK AS HIGH PRESSURE REMAINS OVER THE AREA AND SW FLOW INCREASES AHEAD OF THE NEXT SYSTEM. TEMPS COULD GET INTO THE LOWER 90S OVER PORTIONS OF THE SE PLAINS. POPS WILL REMAIN BASICALLY NIL...EVEN FOR THE MT AREAS. TUESDAY THROUGH WEDNESDAY...A SUBTROPICAL LOW PRESSURE SYSTEM WILL MOVE OUT OF THE BAJA REGION ON TUE AND INTO THE DESERT SW...IN A TRAJECTORY THAT WILL MOVE IT THROUGH NW CO ON WED. THE BULK OF THE MOISTURE LOOKS TO IMPACT THE SW MTS TUE AFTERNOON AND EVENING. IT LOOKS LIKE MOST OF THE QPF WILL FALL OVER AZ...SO FLASH FLOODING RISK SHOULD BE LESS...BUT WILL STILL HAVE TO WATCH FOR SOME LOCALIZED MODERATE-HEAVY RAIN. THE SYSTEM THEN SHEARS OUT OVER THE ROCKIES...LEAVING ONLY SPOTTY CONVECTION FOR THE ERN MTS AND PLAINS ON WED. TEMPS REMAIN IN THE 80S FOR THE PLAINS...OR ABOUT 5-10 DEGREES ABOVE AVERAGE. THURSDAY-FRIDAY...WILL SEE A SLIGHT FRONTAL PUSH ON THU BEHIND THE DEPARTING SYSTEM...BUT DUE TO ITS SW-NE TRAJECTORY WILL NOT SEE MUCH COLD AIR BEHIND THE TROUGH...SO TEMPS LIKELY TO REMAIN IN THE 70S AND 80S FOR THE END OF THE WEEK. WITH DRY QUASI-ZONAL FLOW BECOMING RE-ESTABLISHED OVER THE AREA...POPS WILL REMAIN LOW. NEXT CHANCE OF ANY SIGNIFICANT WX WILL NOT COME UNTIL AT LEAST NEXT SATURDAY...AS A PACNW SYSTEM STARTS TO ADVANCE EWD INTO THE ROCKIES. THE ECMWF IS A BIT SLOWER AND DEEPER WITH THIS SYSTEM...WHILE THE GFS DELIVERS ANOTHER QUICK SHOT OF PRECIP TO THE AREA LATE NEXT WEEKEND. ENSEMBLE SPREADS ARE NOT VERY WIDE...AND SHOW A GENERALLY WEAK SYSTEM FINALLY MOVING INTO THE AREA BY EARLY THE FOLLOWING WEEK. SO...NOT MUCH HOPE FOR ANY INTERESTING WEATHER THROUGH THE END OF SEPTEMBER...BUT IT WILL PROBABLY BE A GOOD TIME TO GET OUTSIDE PROJECTS DONE. ROSE && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 231 PM MDT SAT SEP 19 2015 VFR CONDITIONS ARE EXPECTED TONIGHT THROUGH SUNDAY AFTERNOON AS RELATIVELY DRY AIR REMAINS OVER THE AREA AND AN UPR RIDGE BUILDS INTO CO ON SUN. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...28 LONG TERM...ROSE AVIATION...28
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1124 PM MDT FRI SEP 18 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 208 PM MDT FRI SEP 18 2015 ...COOLER WEATHER CONTINUES ON SATURDAY... STRETCH OF BEAUTIFUL FALL-LIKE WEATHER SHOULD CONTINUE ON SATURDAY AS HIGH PRESSURE DOMINATES AND DRY WESTERLY FLOW PERSISTS. UPSLOPE REGIME OVER THE PLAINS WILL ALLOW FOR ANOTHER DAY OF SEASONABLE TEMPS ON SATURDAY. HIGH RES MODELS INCLUDING THE HRRR CONTINUE TO INDICATE SOME ISOLD SHOWER OR TS DEVELOPING LATE THIS AFTERNOON OVER NRN TELLER COUNTY. THERE IS SOME CU OVER THAT AREA THIS AFTERNOON SO CANNOT RULE IT OUT...AND WILL LEAVE SOME LOW POPS OVER THE PIKES PEAK REGION AND ALSO OVER THE HYR TRRN IN NRN FREMONT COUNTY AND MOSQUITO RANGE THRU THIS EVENING. HAVE TRIMMED BACK POPS ELSEWHERE SINCE THE PROBABILITY LOOKS TOO LOW OVER THE ERN RANGES AND CENTRAL MTS. ANYTHING THAT GETS GOING LATER TODAY SHOULD WIND DOWN THIS EVE. THE HRRR INDICATES CONVECTION DRIFTING NWD TONIGHT...SO MAY BE ABLE TO PULL POPS OUT COMPLETELY IF THINGS DON`T DEVELOP BY EARLY EVE. OVERNIGHT...WILL BE COOL WITH CLEARING SKIES AND WINDS DIMINISHING. SOME LOWS IN THE UPR 40S POSSIBLE OVER THE PLAINS. A FEW AREAS OF LOWER CLOUDS WILL BE POSSIBLE BUT SHOULD NOT BE TOO EXTENSIVE. SATURDAY...FAIRLY SIMILAR TEMPS EXPECTED AS THE COOLER AIR REMAINS WITH US...AND SFC WINDS SHIFT AROUND TO THE SE. SHOULD TOP OUT AROUND 80 DEGREES FOR THE PLAINS...WHILE THE MTS AND HIGH VALLEYS REMAIN IN THE 60S TO LOWER 70S. A SHORT WAVE WILL MOVE THROUGH THE CENTRAL ROCKIES IN THE AFTERNOON...AND THIS COULD SPARK A FEW SHOWERS OR STORMS MAINLY OVER THE HIGHER TRRN LATE IN THE AFTERNOON...BUT NOT EXPECTING ANYTHING TOO WIDESPREAD OR HEAVY. SHOULD BE A RATHER PLEASANT FALL-LIKE DAY ACROSS THE CWA. ROSE .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 208 PM MDT FRI SEP 18 2015 A SHORTWAVE TROF MOVING THRU THE AREA SAT NIGHT MAY BRING SOME ISOLD PCPN TO LOCATIONS FROM THE ERN MTNS TO THE ERN BORDER...WHICH SHOULD END TOWARD SUN MORNING. AN UPR RIDGE WL BUILD OVR THE AREA FOR SUN AND MON WITH DRY WX EXPECTED AND ABOVE AVERAGE HIGH TEMPS. ON TUE AN UPR TROF IS EXPECTED TO MOVE OVR SRN CA AND THE SW FLOW ALOFT AHEAD OF THIS SYSTEM WL BRING AN INCREASE IN MSTR AND A CHANCE FOR PCPN TO MAINLY THE SW CO MTNS LATE IN THE AFTERNOON. THE ECMWF IS A LITTLE SLOWER BRINGING THE MSTR INTO THE AREA THAN THE GFS. TUE NIGHT AND EARLY WED A SHORTWAVE TROF MOVES ACRS CO AND WL HAVE THE POTENTIAL TO BRING ISOLD TO SCT PCPN TO MUCH OF THE FORECAST AREA. THE ECMWF SHOWS A SLOWER MOVING TROF OVR THE AREA WED AND INTO THE FIRST HALF OF THU...WITH ISOLD TO SCT PCPN CHANCES FOR MUCH OF THE AREA. LOW LEVEL UPSLOPE FLOW IS EXPECTED ON THU AND THERE MAY BE SOME SCT PCPN OVR AND NR THE MTNS AREAS. AN UPR RIDGE IS EXPECTED OVR THE AREA ON FRI. THE GFS SHOWS A MONSOON MSTR TAP INTO THE AREA FRI...WHILE THE ECMWF IS DRIER. SO THERE MAY BE SOME ISOLD TO SCT PCPN CHANCES ON FRI. IT GENERALLY LOOKS LIKE HIGH TEMPS TUE THRU FRI WL BE ABOVE AVERAGE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1117 PM MDT FRI SEP 18 2015 VFR CONDITIONS EXPECTED NEXT 24H AT ALL 3 TAF SITES...KPUB...KALS AND KCOS. SFC WINDS WILL BE DIURNALLY DRIVEN. THERE IS A VERY LOW CHANCE OF AN ISOLD -TSRA AT KCOS AND KPUB TOMOROW AFTERNOON...BUT PROBABILITY TOO LOW TO EXPLICITLY MENTION IN TAF PRODUCT ATTM. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...ROSE LONG TERM...28 AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS ALBANY NY
206 PM EDT SAT SEP 19 2015 .SYNOPSIS... A VERY WARM AIR MASS WILL PERSIST THROUGH THIS AFTERNOON WITH HIGH PRESSURE ALONG THE EAST COAST. HOWEVER...A COLD FRONT APPROACHING FROM THE GREAT LAKES WILL CROSS OUR REGION TONIGHT...BRINGING SOME SHOWERS AND USHERING IN A COOLER AND MORE SEASONABLE AIR MASS FOR SUNDAY INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... JUST SOME MINOR ADJUSTMENTS BASED ON THE TIMING OF ONSET OF SCATTERED SHOWERS. OTHERWISE CURRENT FORECAST GENERALLY IN LINE WITH CURRENT DATA AND TRENDS THROUGH THIS AFTERNOON. PREVIOUS DISCUSSION... ADDITIONAL CLOUDS INCREASE FROM THE WEST ASSOCIATED WITH A COLD FRONT APPROACHING FROM THE GREAT LAKES LATE IN THE DAY. ONE MORE WARM DAY IS EXPECTED...WITH SUNSHINE AND A SOUTHERLY FLOW RESULTING IN HIGH TEMPS IN THE UPPER 70S TO LOWER 80S. MOST OF THE AREA SHOULD REMAIN DRY THROUGH THE DAYLIGHT HOURS. HOWEVER...CHANCES FOR SHOWERS WILL START TO INCREASE FOR THE WESTERN ADIRONDACKS/MOHAWK VALLEY LATE IN THE DAY AS THE COLD FRONT MOVES INTO WESTERN NY. BASED ON TIMING FROM HRRR AND LOCAL HI-RES WRF...WILL ONLY MENTION 20-30 POPS FOR HERKIMER/HAMILTON COUNTIES THROUGH 6 PM TODAY. THE BULK OF THE SHOWERS WILL ARRIVE AFTER DARK. && .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/... SHOWERS WILL BE MOVING INTO WESTERN PORTIONS OF THE AREA EARLY THIS EVENING...PRECEDING A COLD FRONT PUSHING EASTWARD ACROSS NY STATE. MODELS INDICATING A NARROW RIBBON OF WEAK INSTABILITY JUST AHEAD OF THE FRONT...SO WILL MENTION ISOLATED THUNDER ACROSS PORTIONS OF THE WESTERN ADIRONDACKS. SOME BRIEF GUSTY WINDS WILL ALSO BE POSSIBLE WITH THE LINE OF SHOWERS/STORMS FOR THIS AREA...BUT THERE WILL NOT BE ENOUGH INSTABILITY TO SUSTAIN TALL ENOUGH UPDRAFTS TO PRODUCE STRONGER WINDS. MODELS INDICATE THE LINE OF SHOWERS WILL BE WEAKENING SOMEWHAT AS THEY MOVE EAST DURING THE LATE EVENING AND OVERNIGHT HOURS. SO WILL MAINLY MENTION CHANCE POPS FOR MUCH OF THE AREA WITH LIGHT QPF AMOUNTS. THE COLD FRONT AND ANY ASSOCIATED SHOWERS SHOULD CLEAR THE ENTIRE AREA BY DAYBREAK SUNDAY. WINDS WILL BECOME NORTHERLY BEHIND THE FRONT AND WILL BE NOTICEABLE ALONG WITH COOLER TEMPERATURES. HIGHS ARE ONLY EXPECTED TO BE IN THE 60S TO NEAR 70...WHICH IS NEAR NORMAL BUT MUCH COOLER THAN RECENT DAYS. CLOUDS WILL DECREASE THROUGHOUT THE DAY AS HIGH PRESSURE BUILDS SOUTHWARD ACROSS THE AREA. HIGH PRESSURE WILL SETTLE IN OVER THE REGION SUNDAY NIGHT INTO MONDAY MORNING...RESULTING IN CLEAR SKIES AND LIGHT WINDS. THESE CONDITIONS WILL ALLOW FOR THE COOLEST OVERNIGHT TEMPERATURES WE HAVE SEEN IN THREE MONTHS. LOWS ARE FORECAST TO BE IN THE UPPER 30S TO MID 40S...WITH PATCHY FROST POSSIBLE FOR SOME AREAS NORTH AND EAST OF ALBANY. THE LAST DAY ALBANY OFFICIALLY HAD A TEMPERATURE IN THE 40S WAS BACK ON JUNE 20TH...WHICH WAS 49 DEGREES THAT MORNING. TRANQUIL WEATHER WILL PERSIST MONDAY AND MONDAY NIGHT...WITH HIGH PRESSURE REMAINING IN CONTROL. TEMPERATURES LOOK TO BE CLOSE TO NORMAL. MONDAY NIGHT WILL LIKELY NOT BE AS COLD AS THE PREVIOUS NIGHT DUE TO SOME POSSIBLE ADDED CLOUD COVER AND A SLIGHT EASTERLY BREEZE...AS THE CENTER OF THE HIGH PRESSURE SYSTEM RETREATS TOWARDS THE CANADIAN MARITIMES. && .LONG TERM /TUESDAY THROUGH FRIDAY/... THE LONG TERM PERIOD STARTS OUT DRY AND SEASONABLE AS A LARGE RIDGE OF HIGH PRESSURE EXTENDS FROM THE OHIO VALLEY NORTHEASTWARD INTO THE NORTHEASTERN US. A WEAK COLD FRONT IS EXPECTED TO DROP SOUTHEAST FROM SOUTHERN CANADA THROUGH THE NORTHEAST ON WEDNESDAY AND STALL ACROSS THE MIDDLE ATLANTIC REGION ON THURSDAY. AT THIS TIME EXPECT THE FRONTAL PASSAGE WILL BE DRY WITH MODEL GUIDANCE INDICATING LITTLE IF ANY MOISTURE WITH THE FRONTAL BOUNDARY. FRIDAY AT THIS POINT IS A DIFFICULT FORECAST AS THE MODELS DIVERGE ON WHETHER OR NOT MOISTURE FROM THE SOUTH LIFTS NORTH WITH THE FRONTAL BOUNDARY STALLED JUST TO OUR SOUTH. AT THIS TIME THE GFS LIFTS MOISTURE NORTHWARD ACROSS OUR REGION ON FRIDAY WHILE THE ECMWF IS DRY WITH HIGH PRESSURE REMAINING IN CONTROL OF OUR WEATHER. FOR NOW WILL PLACE SLIGHT CHANCE POPS IN THE GRIDS FOR FRIDAY. TEMPERATURES FOR THE LONG TERM PERIOD WILL BE SEASONABLE TO SLIGHTLY BELOW NORMAL. EXPECT HIGHS TUESDAY TO BE IN THE MID 60S TO MID 70S WITH HIGHS ON WEDNESDAY AND THURSDAY IN THE UPPER 60S TO MID 70S AND HIGHS ON FRIDAY IN THE 60S TO AROUND 70 ALTHOUGH IT COULD BE COOLER IF THE GFS IS CORRECT. LOWS WILL BE IN THE 40S TO LOWER 50S TUESDAY NIGHT THROUGH THURSDAY NIGHT. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... DESPITE A COLD FRONT MOVING THROUGH THE REGION TONIGHT...EXPECT VFR CONDITIONS AT THE TAF SITES FOR MOST OF THE TAF PERIOD. SHOWERS ASSOCIATED WITH THE FRONT WILL BEGIN TO DIMINISH AFTER SUNSET...AND MAINLY LIGHT RAIN SHOWERS...IF ANY...ARE EXPECTED TO AFFECT THE TAF SITES BETWEEN 02Z AND 09Z. HAVE ONLY INCLUDED VCSH AT THE KALB/KPSF/KPOU TAF SITES...AND 6SM -SHRA T KGFL. OTHERWISE HAVE FORECAST ONLY VFR CONDITIONS AT THE TAF SITES. SOUTH TO SOUTHWEST WINDS FOR THE REST OF THE AFTN AND INTO THIS EVENING AT 8 TO 12 KTS...WITH GUSTS UP TO 20 KTS. THE WINDS WILL DECREASE SOMEWHAT AFTER SUNSET...BUT REMAIN STRONG ENOUGH TO PREVENT ANY FOG FORMATION TONIGHT. THE FRONT WILL MOVE THROUGH BETWEEN 05Z AND 09...WITH WINDS SHIFTING TO WESTERLY AND THEN NORTHWWEST TO NORTH AT 8 TO 10 KTS WITH GUSTS AORUND 15 KTS. OUTLOOK... SUN AFTN-WED: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... A VERY WARM AIR MASS WILL PERSIST THROUGH TODAY WITH HIGH PRESSURE ALONG THE EAST COAST. HOWEVER...A COLD FRONT APPROACHING FROM THE GREAT LAKES WILL CROSS OUR REGION TONIGHT BRINGING SOME SHOWERS AND USHERING IN A COOLER AND MORE SEASONABLE AIR MASS FOR SUNDAY INTO EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITY VALUES TODAY WILL BE AROUND 45 TO 50 PERCENT...INCREASING TO MAXIMUM VALUES OF 85 TO 100 PERCENT TONIGHT. MIN RH VALUES ON SUNDAY ARE FORECAST TO BE BETWEEN 35 AND 45 PERCENT. WINDS TODAY WILL BE SOUTHERLY AROUND 10 TO 15 MPH...BECOMING NORTHWEST AT 5 TO 15 MPH TONIGHT AS A COLD FRONT PASSES THROUGH. WINDS ON SUNDAY WILL BECOME NORTHERLY AROUND 5 TO 15 MPH. && .HYDROLOGY... NO HYDROLOGIC CONCERNS THROUGH THE NEXT FIVE DAYS. DRY CONDITIONS WILL PERSIST THROUGH MUCH OF TODAY. A COLD FRONT WILL CROSS THE REGION FROM WEST TO EAST TONIGHT WITH MAINLY SCATTERED SHOWERS EXPECTED. SHOWERS WILL BE MORE NUMEROUS ACROSS THE WESTERN ADIRONDACKS WHERE ONE QUARTER TO ONE THIRD OF AN INCH OF RAINFALL IS POSSIBLE. ELSEWHERE GENERALLY A TENTH OF AN INCH OR LESS IS EXPECTED. THE RAINFALL WILL HAVE LITTLE...IF ANY IMPACT ON AREA RIVERS. DRY CONDITIONS RETURN FOR SUNDAY AND WILL LIKELY LAST THROUGH AT LEAST THE MIDDLE OF NEXT WEEK WITH ANOTHER AREA OF HIGH PRESSURE BUILDING IN. RIVER FLOWS WILL CONTINUE TO RECEDE INTO NEXT WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...JPV NEAR TERM...NAS/JPV SHORT TERM...JPV LONG TERM...11 AVIATION...GJM FIRE WEATHER...JPV HYDROLOGY...JPV
AREA FORECAST DISCUSSION
NWS TAUNTON MA
141 PM EDT SAT SEP 19 2015 .SYNOPSIS... HIGH PRESSURE WILL REMAIN IN CONTROL TODAY...WITH A COLD FRONT BRINGING JUST A FEW SHOWERS LATE TONIGHT INTO EARLY SUNDAY. HIGH PRESSURE THEN BUILDS INTO NORTHERN NEW ENGLAND FOR MUCH OF NEXT WEEK. LOW PRESSURE WELL OFFSHORE TO THE SOUTH MAY BRING SHOWERS CLOSE TO THE ISLANDS TUESDAY...OTHERWISE DRY WEATHER THROUGH THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 10 AM UPDATE... ALLOWED THE DENSE FOG ADVISORY TO EXPIRE NATURALLY AS MOST LOCATIONS HAD LIFTED TO AT LEAST 0.5 MILES OR HIGHER. STILL SOME AREAS WHERE FOG IS HANGING IN...BUT VSBYS ALL SHOWING SIGNS OF RISING. OTHERWISE...FORECAST REQUIRED A BIT MORE MANUAL ADJUSTMENT THIS MORNING AS THE STRATUS DEC CONTINUES TO HOLD FAST AS OF 1O AM. SKIES WERE THE FIRST THING THAT NEEDED ADJUSTING. HOWEVER...THIS IS ALSO IMPACTING THE TEMPS...AND ARE LIKELY TO IMPACT THE HIGHS THIS AFTERNOON. GUIDANCE...EVEN IN THE SHORT TERM ARE NOT REALLY HANDLING THIS WELL. SO STARTED WITH A BASELINE OF 2M HRRR TEMPS COMBINED WITH OUR IN-HOUSE BIAS CORRECTED MAV. THIS PRESENTED A GOOD FOUNDATION BUT THEN MADE MANUAL EDITS FROM THERE BASED ON THE TIMING OF CLOUD COVER CLEARING. THE OVERALL FINAL NUMBERS ARE A BIT LOWER THAN PREVIOUS. PREVIOUS DISCUSSION... AFTER ANY EARLY MORNING FOG BURNS OFF...EXPECTING ANOTHER MOSTLY SUNNY...WARM DAY BEFORE A COLD FRONT MOVES THROUGH TONIGHT. HIGH TEMPERATURES ARE EXPECTED TO BE IN THE UPPER 70S TO LOWER 80S MOST LOCATIONS. SLIGHTLY COOLER TEMPERATURES EXPECTED ALONG THE SOUTH COAST WITH AN ONSHORE WIND. INCREASING DEWPOINTS WILL LEAD TO A MORE HUMID FEELING TO THE DAY...BUT IT SHOULD NOT FEEL OPPRESSIVE. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/... TONIGHT...LOW PRESSURE MOVES THROUGH QUEBEC BRINGING A COLD FRONT THROUGH SOUTHERN NEW ENGLAND. THERE IS ENOUGH MOISTURE AVAILABLE... AS INDICATED BY K INDICES...FOR SHOWERS TO DEVELOP. INSTABILITY AND MID LEVEL LAPSE RATES ARE LACKING SO NO THUNDER IS EXPECTED. NOT EXPECTING WIDESPREAD RAIN OVERNIGHT BUT SOME LOCATIONS WILL LIKELY HAVE A SHOWER OR TWO. DESPITE ABOVE NORMAL PWAT VALUES...RAINFALL AMOUNTS WILL BE LESS THAN A QUARTER INCH. NOT ENOUGH TO MAKE MUCH OF A DIFFERENCE IN THE RAINFALL DEFICIT. INCREASING CLOUDS...CHANCE OF SHOWERS...AND INCREASED DEWPOINTS... WILL COMBINE TO KEEP OVERNIGHT TEMPERATURES A BIT WARMER THAN PREVIOUS NIGHTS. THE ONLY EXCEPTION TO THIS MAY BE IN NORTHWESTERN MASSACHUSETTS WHERE COLD ADVECTION BEHIND THE FRONT MAY BEGIN BY THE EARLY MORNING HOURS. SUNDAY...MOST PRECIP SHOULD HAVE COME TO AN END BY SUNRISE SUNDAY MORNING. THERE IS A LOW PROBABILITY THAT A FEW SHOWERS MAY LINGER ON THE CAPE AND ISLANDS EARLY BEFORE THE FRONT PUSHES OFFSHORE. HIGH PRESSURE BUILDS INTO NORTHERN NEW ENGLAND BRINGING DRY WEATHER TO THE REGION. EXPECT STRONG COLD ADVECTION TO HOLD OFF UNTIL AFTER SUNSET SUNDAY SO MUCH OF THE DAY WILL BE PLEASANT WITH SUNNY SKIES AND MORE SEASONABLE TEMPERATURES. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... BIG PICTURE... UPPER TROUGH OVER THE GULF OF ALASKA WITH NEAR-ZONAL FLOW ACROSS THE PACIFIC NORTHWEST AND CANADA. SOUTHERN NEW ENGLAND REMAINS SOUTH OF THIS NORTHERN JET THROUGH THE FORECAST PERIOD. SOUTHERN STREAM UPPER LOW LOITERS OVER THE SOUTHEAST USA THROUGH THE WEEK. THE GFS EJECTS THIS LOW TOWARD NEW ENGLAND AT THE END OF THE WEEK WHILE THE ECMWF MOVES IT SOUTHWEST TOWARD THE GULF OF MEXICO. THE LARGE SCALE PATTERN IS DRY AND WARM WITH 500 MB CONTOURS MOSTLY ABOVE NORMAL. HOWEVER A LOW LEVEL EAST/NORTHEAST FLOW WOULD BUFFER SURFACE TEMPS SEVERAL DEGREES...CLOSER TO NORMAL OR A LITTLE BELOW. THE DAILIES... SUNDAY NIGHT-MONDAY... HIGH PRESSURE BUILDS OVER NORTHERN NEW ENGLAND WITH SHORTWAVE RIDGE ALOFT. THIS SHOULD PROVIDE GENERAL SUBSIDENCE. POSITIONING OF THE HIGH CENTER WILL BRING A NORTHEAST FLOW ACROSS SOUTHERN NEW ENGLAND...STRONGEST NEAR THE EAST MASSACHUSETTS SHORE. THIS SUGGESTS MOSTLY CLEAR SKIES WITH LIGHT WIND INLAND AND A BUFFERING EAST/NORTHEAST WIND FLOW NEAR THE EASTERN SHORE. RADIATIONAL COOLING SUNDAY NIGHT SHOULD BRING SFC TEMPS TO NEAR THE DEW POINT. INLAND DEWS WILL BE IN THE UPPER 30S TO LOWER 40S...COASTAL DEWS IN THE MID 40S TO LOWER 50S. EAST FLOW WILL LIMIT MIXING DEPTHS...BASED ON TEMPS AT 900 MB THIS WOULD SUPPORT MONDAY MAX TEMPS IN THE MID AND UPPER 60S NEAR THE SHORE AND LOWER 70S INLAND. TUESDAY THROUGH THURSDAY... HIGH PRESSURE IN CONTROL MUCH OF THE TIME OVER NEW ENGLAND. A WEAK SHORTWAVE MOVES THROUGH THE REGION WEDNESDAY WITH VERY LIMITED MOISTURE NOTED ON THE MODELS. MAYBE ENOUGH FOR A PERIOD OF CLOUDS...BUT NO PCPN. FRIDAY...THE ECMWF BUILDS CANADIAN HIGH PRESSURE OVER THE REGION WITH A NORTHWEST UPPER FLOW. THE GFS IS MORE SHALLOW WITH A SHORTWAVE OVER QUEBEC FRIDAY AND FRIDAY NIGHT...ALSO FARTHER NORTH WITH SOUTHERN STREAM UPPER LOW MOVING THROUGH CAROLINAS INTO DELMARVA AREA. THIS BRINGS SHOWERS FARTHER NORTH ON FRIDAY AS WELL AS THE LEFT FRONT QUADRANT OF ASSOCIATED UPPER JET. THE ECMWF SCENARIO IS FOR DRY WEATHER. THE GFS SCENARIO WOULD SUGGEST A CHANCE OF SHOWERS ON FRIDAY...BUT ITS SUDDEN APPEARANCE ON THIS RUN AND IN THE FINAL PERIOD OF THE FORECAST DOES NOT GENERATE A LOT OF CONFIDENCE. WE WILL GO WITH THE DRY ECMWF SCENARIO. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH SUNDAY NIGHT/... THROUGH 02Z TONIGHT...HIGH CONFIDENCE. MAINLY VFR WITH SSW FLOW 5-10 KT. AFTER 02Z TONIGHT TO ABOUT 10Z TOMORROW MORNING...MODERATE CONFIDENCE. EXPECT SIMILAR CONDITIONS TO LAST NIGHT WITH LOW CLOUDS AND FOG BUILDING FROM THE S COAST INLAND THROUGH THE OVERNIGHT HOURS. TIMING MAY BE OFF SOMEWHAT IN THE TAFS. THE PRIMARY DIFFERENCE WILL BE THE RISK FOR SHWRS WHICH MAY SCOUR THINGS OUT TO MAINLY MVFR ESPECIALLY NW OF A HFD-ORH-BVY LINE...AREAS SE MAY REMAIN IFR/LIFR AT TIMES. 10Z TOMORROW MORNING THROUGH SUNDAY NIGHT...HIGH CONFIDENCE. EXPECT IMPROVEMENT AS THE COLD FRONT MOVES THROUGH AND WINDS SHIFT TO THE NW /PICKING UP WITH GUSTS 10-15 KT/. MAINLY VFR ALL TERMINALS BY MID DAY...REMAINING VFR INTO SUN NIGHT. KBOS TERMINAL...MODERATE CONFIDENCE IN TAF...MAINLY WITH TIMING AND PERSISTENCE OF LATE NIGHT IFR CONDITIONS. KBDL TERMINAL...MODERATE CONFIDENCE IN TAF...MAINLY WITH TIMING AND PERSISTENCE OF LATE NIGHT IFR CONDITIONS. OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE TO HIGH CONFIDENCE. VFR THROUGH THE PERIOD. NORTHEAST TO EAST WINDS ARE EXPECTED MONDAY WITH GUSTS 20 TO 25 KNOTS MAINLY ACROSS CAPE COD AND ISLANDS. EAST TO NORTHEAST FLOW CONTINUES THROUGH MIDWEEK WITH LIGHTER WINDS IN THE INTERIOR. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH SUNDAY/...HIGH CONFIDENCE. FOG MAY LIMIT VISIBILITIES THIS MORNING...BUT SHOULD THIN DURING THE MORNING HOURS. THEN HIGH PRESSURE OVER THE WATERS WILL BRING LIGHT WINDS AND CALM SEAS THROUGH SUNDAY MORNING. WINDS AND SEAS BUILD SUNDAY AFTERNOON AS A COLD FRONT CROSSES THE WATERS. SCA CONDITIONS MAY OCCUR BY SUNDAY EVENING. OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...HIGH CONFIDENCE. HIGH PRESSURE BUILDS OVER NORTHERN NEW ENGLAND WITH EAST TO NORTHEAST WINDS ACROSS THE MASS AND RI COASTAL WATERS. LOW LEVEL FLOW SUPPORTS WINDS 20 TO 25 KNOTS SUNDAY NIGHT AND MONDAY THEN DIMINISHING. THESE WINDS WILL MAINTAIN 5 TO 7 FOOT SEAS ON THE OUTER WATERS AND MASS BAY...POSSIBLY CAPE COD BAY. WINDS DIMINISH THROUGH MIDWEEK WHILE SEAS SUBSIDE VERY SLOWLY. SMALL CRAFT ADVISORY CONTINUES THROUGH AT LEAST MONDAY...AND POSSIBLY LINGERING SMALL CRAFTS FOR SEAS ON THE OUTER WATERS THROUGH MIDWEEK. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. RI...NONE. MARINE...NONE. && $$ SYNOPSIS...WTB/RLG NEAR TERM...DOODY/RLG SHORT TERM...RLG LONG TERM...WTB AVIATION...WTB/DOODY MARINE...WTB/RLG
AREA FORECAST DISCUSSION
NWS ALBANY NY
105 PM EDT SAT SEP 19 2015 .SYNOPSIS... A VERY WARM AIR MASS WILL PERSIST THROUGH THIS AFTERNOON WITH HIGH PRESSURE ALONG THE EAST COAST. HOWEVER...A COLD FRONT APPROACHING FROM THE GREAT LAKES WILL CROSS OUR REGION TONIGHT...BRINGING SOME SHOWERS AND USHERING IN A COOLER AND MORE SEASONABLE AIR MASS FOR SUNDAY INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... JUST SOME MINOR ADJUSTMENTS BASED ON THE TIMING OF ONSET OF SCATTERED SHOWERS. OTHERWISE CURRENT FORECAST GENERALLY IN LINE WITH CURRENT DATA AND TRENDS THROUGH THIS AFTERNOON. PREVIOUS DISCUSSION... ADDITIONAL CLOUDS INCREASE FROM THE WEST ASSOCIATED WITH A COLD FRONT APPROACHING FROM THE GREAT LAKES LATE IN THE DAY. ONE MORE WARM DAY IS EXPECTED...WITH SUNSHINE AND A SOUTHERLY FLOW RESULTING IN HIGH TEMPS IN THE UPPER 70S TO LOWER 80S. MOST OF THE AREA SHOULD REMAIN DRY THROUGH THE DAYLIGHT HOURS. HOWEVER...CHANCES FOR SHOWERS WILL START TO INCREASE FOR THE WESTERN ADIRONDACKS/MOHAWK VALLEY LATE IN THE DAY AS THE COLD FRONT MOVES INTO WESTERN NY. BASED ON TIMING FROM HRRR AND LOCAL HI-RES WRF...WILL ONLY MENTION 20-30 POPS FOR HERKIMER/HAMILTON COUNTIES THROUGH 6 PM TODAY. THE BULK OF THE SHOWERS WILL ARRIVE AFTER DARK. && .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/... SHOWERS WILL BE MOVING INTO WESTERN PORTIONS OF THE AREA EARLY THIS EVENING...PRECEDING A COLD FRONT PUSHING EASTWARD ACROSS NY STATE. MODELS INDICATING A NARROW RIBBON OF WEAK INSTABILITY JUST AHEAD OF THE FRONT...SO WILL MENTION ISOLATED THUNDER ACROSS PORTIONS OF THE WESTERN ADIRONDACKS. SOME BRIEF GUSTY WINDS WILL ALSO BE POSSIBLE WITH THE LINE OF SHOWERS/STORMS FOR THIS AREA...BUT THERE WILL NOT BE ENOUGH INSTABILITY TO SUSTAIN TALL ENOUGH UPDRAFTS TO PRODUCE STRONGER WINDS. MODELS INDICATE THE LINE OF SHOWERS WILL BE WEAKENING SOMEWHAT AS THEY MOVE EAST DURING THE LATE EVENING AND OVERNIGHT HOURS. SO WILL MAINLY MENTION CHANCE POPS FOR MUCH OF THE AREA WITH LIGHT QPF AMOUNTS. THE COLD FRONT AND ANY ASSOCIATED SHOWERS SHOULD CLEAR THE ENTIRE AREA BY DAYBREAK SUNDAY. WINDS WILL BECOME NORTHERLY BEHIND THE FRONT AND WILL BE NOTICEABLE ALONG WITH COOLER TEMPERATURES. HIGHS ARE ONLY EXPECTED TO BE IN THE 60S TO NEAR 70...WHICH IS NEAR NORMAL BUT MUCH COOLER THAN RECENT DAYS. CLOUDS WILL DECREASE THROUGHOUT THE DAY AS HIGH PRESSURE BUILDS SOUTHWARD ACROSS THE AREA. HIGH PRESSURE WILL SETTLE IN OVER THE REGION SUNDAY NIGHT INTO MONDAY MORNING...RESULTING IN CLEAR SKIES AND LIGHT WINDS. THESE CONDITIONS WILL ALLOW FOR THE COOLEST OVERNIGHT TEMPERATURES WE HAVE SEEN IN THREE MONTHS. LOWS ARE FORECAST TO BE IN THE UPPER 30S TO MID 40S...WITH PATCHY FROST POSSIBLE FOR SOME AREAS NORTH AND EAST OF ALBANY. THE LAST DAY ALBANY OFFICIALLY HAD A TEMPERATURE IN THE 40S WAS BACK ON JUNE 20TH...WHICH WAS 49 DEGREES THAT MORNING. TRANQUIL WEATHER WILL PERSIST MONDAY AND MONDAY NIGHT...WITH HIGH PRESSURE REMAINING IN CONTROL. TEMPERATURES LOOK TO BE CLOSE TO NORMAL. MONDAY NIGHT WILL LIKELY NOT BE AS COLD AS THE PREVIOUS NIGHT DUE TO SOME POSSIBLE ADDED CLOUD COVER AND A SLIGHT EASTERLY BREEZE...AS THE CENTER OF THE HIGH PRESSURE SYSTEM RETREATS TOWARDS THE CANADIAN MARITIMES. && .LONG TERM /TUESDAY THROUGH FRIDAY/... THE LONG TERM PERIOD STARTS OUT DRY AND SEASONABLE AS A LARGE RIDGE OF HIGH PRESSURE EXTENDS FROM THE OHIO VALLEY NORTHEASTWARD INTO THE NORTHEASTERN US. A WEAK COLD FRONT IS EXPECTED TO DROP SOUTHEAST FROM SOUTHERN CANADA THROUGH THE NORTHEAST ON WEDNESDAY AND STALL ACROSS THE MIDDLE ATLANTIC REGION ON THURSDAY. AT THIS TIME EXPECT THE FRONTAL PASSAGE WILL BE DRY WITH MODEL GUIDANCE INDICATING LITTLE IF ANY MOISTURE WITH THE FRONTAL BOUNDARY. FRIDAY AT THIS POINT IS A DIFFICULT FORECAST AS THE MODELS DIVERGE ON WHETHER OR NOT MOISTURE FROM THE SOUTH LIFTS NORTH WITH THE FRONTAL BOUNDARY STALLED JUST TO OUR SOUTH. AT THIS TIME THE GFS LIFTS MOISTURE NORTHWARD ACROSS OUR REGION ON FRIDAY WHILE THE ECMWF IS DRY WITH HIGH PRESSURE REMAINING IN CONTROL OF OUR WEATHER. FOR NOW WILL PLACE SLIGHT CHANCE POPS IN THE GRIDS FOR FRIDAY. TEMPERATURES FOR THE LONG TERM PERIOD WILL BE SEASONABLE TO SLIGHTLY BELOW NORMAL. EXPECT HIGHS TUESDAY TO BE IN THE MID 60S TO MID 70S WITH HIGHS ON WEDNESDAY AND THURSDAY IN THE UPPER 60S TO MID 70S AND HIGHS ON FRIDAY IN THE 60S TO AROUND 70 ALTHOUGH IT COULD BE COOLER IF THE GFS IS CORRECT. LOWS WILL BE IN THE 40S TO LOWER 50S TUESDAY NIGHT THROUGH THURSDAY NIGHT. && .AVIATION /17Z SATURDAY THROUGH WEDNESDAY/... FOR TODAY EXPECTING SOME HIGH CLOUDS TO STREAM IN AND EVENTUALLY MID CLOUDS THIS AFTERNOON TO MOVE IN AHEAD AN APPROACHING COLD FRONT. THIS BOUNDARY WILL USHER A MUCH COOLER AND MORE SEASONABLE AIR MASS INTO THE REGION WITH ITS PASSAGE TONIGHT. HAVE INCLUDED -SHRA FOR KGFL AFTER 03Z AND VCSH FOR KALB...KPSF AND KPOU BTWN 03Z AND 05Z AS SHOWERS WILL BE DIMINISHING IN COVERAGE AS THEY MOVE SOUTH AND EAST. CIGS WILL ALSO LOWER TO OVC035-050 BTWN 03Z AND 05Z. SKIES WILL THEN BECOME SCT035-045 LATE TONIGHT IN THE WAKE OF THE COLD FRONT. CALM WINDS WILL BECOME SOUTHERLY TODAY AS THE FLOW WILL PICK UP DURING THE DAY TO 8 TO 12 KNOTS WITH SOME 15-22 KTS EXPECTED AT KGFL...KPSF AND ESPECIALLY KALB DURING THE AFTERNOON. WINDS WILL REMAIN BTWN 08-12 KTS THIS EVENING BEFORE SHIFTING TO THE WEST- NORTHWEST WITH THE FRONTAL PASSAGE LATE TONIGHT. OUTLOOK... SUN-WED: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... A VERY WARM AIR MASS WILL PERSIST THROUGH TODAY WITH HIGH PRESSURE ALONG THE EAST COAST. HOWEVER...A COLD FRONT APPROACHING FROM THE GREAT LAKES WILL CROSS OUR REGION TONIGHT BRINGING SOME SHOWERS AND USHERING IN A COOLER AND MORE SEASONABLE AIR MASS FOR SUNDAY INTO EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITY VALUES TODAY WILL BE AROUND 45 TO 50 PERCENT...INCREASING TO MAXIMUM VALUES OF 85 TO 100 PERCENT TONIGHT. MIN RH VALUES ON SUNDAY ARE FORECAST TO BE BETWEEN 35 AND 45 PERCENT. WINDS TODAY WILL BE SOUTHERLY AROUND 10 TO 15 MPH...BECOMING NORTHWEST AT 5 TO 15 MPH TONIGHT AS A COLD FRONT PASSES THROUGH. WINDS ON SUNDAY WILL BECOME NORTHERLY AROUND 5 TO 15 MPH. && .HYDROLOGY... NO HYDROLOGIC CONCERNS THROUGH THE NEXT FIVE DAYS. DRY CONDITIONS WILL PERSIST THROUGH MUCH OF TODAY. A COLD FRONT WILL CROSS THE REGION FROM WEST TO EAST TONIGHT WITH MAINLY SCATTERED SHOWERS EXPECTED. SHOWERS WILL BE MORE NUMEROUS ACROSS THE WESTERN ADIRONDACKS WHERE ONE QUARTER TO ONE THIRD OF AN INCH OF RAINFALL IS POSSIBLE. ELSEWHERE GENERALLY A TENTH OF AN INCH OR LESS IS EXPECTED. THE RAINFALL WILL HAVE LITTLE...IF ANY IMPACT ON AREA RIVERS. DRY CONDITIONS RETURN FOR SUNDAY AND WILL LIKELY LAST THROUGH AT LEAST THE MIDDLE OF NEXT WEEK WITH ANOTHER AREA OF HIGH PRESSURE BUILDING IN. RIVER FLOWS WILL CONTINUE TO RECEDE INTO NEXT WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...JPV NEAR TERM...NAS/JPV SHORT TERM...JPV LONG TERM...11 AVIATION...GJM FIRE WEATHER...JPV HYDROLOGY...JPV
AREA FORECAST DISCUSSION
NWS ALBANY NY
1104 AM EDT SAT SEP 19 2015 .SYNOPSIS... A VERY WARM AIR MASS WILL PERSIST THROUGH TODAY WITH HIGH PRESSURE ALONG THE EAST COAST. HOWEVER...A COLD FRONT APPROACHING FROM THE GREAT LAKES WILL CROSS OUR REGION TONIGHT...BRINGING SOME SHOWERS AND USHERING IN A COOLER AND MORE SEASONABLE AIR MASS FOR SUNDAY INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1045 AM EDT...SUNNY TO MOSTLY SUNNY AROSS THE REGION WITH THE EXCEPTION OF THE CONNECTICUT VALLEY IN SOUTHEAST VERMONT WHERE STRATUS IS STILL HANGING ON...BUT IT SHOULD BURN OFF BY AROUND NOON. WIDESPREAD CLOUDINESS ALSO SEEN OVER LAKE ONTARIO...WHICH WILL BEGIN TO SPREAD INTO THE ADIRONDACKS DURING THE AFTERNOON. HAVE ONLY MADE SOME MINOR TEMP ADJUSTMENTS...AND ASLO SOME ADJUSTMENTS TO THE SKY COVER GRIDS TO REFLECT CURRETN CONDITIONS... OTHERWISE THE PREVIOUS FORECAST WAS IN GOOD SHAPE. PREVIOUS DISCUSSION... ADDITIONAL CLOUDS INCREASE FROM THE WEST ASSOCIATED WITH A COLD FRONT APPROACHING FROM THE GREAT LAKES LATE IN THE DAY. ONE MORE WARM DAY IS EXPECTED...WITH SUNSHINE AND A SOUTHERLY FLOW RESULTING IN HIGH TEMPS IN THE UPPER 70S TO LOWER 80S. MOST OF THE AREA SHOULD REMAIN DRY THROUGH THE DAYLIGHT HOURS. HOWEVER...CHANCES FOR SHOWERS WILL START TO INCREASE FOR THE WESTERN ADIRONDACKS/MOHAWK VALLEY LATE IN THE DAY AS THE COLD FRONT MOVES INTO WESTERN NY. BASED ON TIMING FROM HRRR AND LOCAL HI-RES WRF...WILL ONLY MENTION 20-30 POPS FOR HERKIMER/HAMILTON COUNTIES THROUGH 6 PM TODAY. THE BULK OF THE SHOWERS WILL ARRIVE AFTER DARK. && .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/... SHOWERS WILL BE MOVING INTO WESTERN PORTIONS OF THE AREA EARLY THIS EVENING...PRECEDING A COLD FRONT PUSHING EASTWARD ACROSS NY STATE. MODELS INDICATING A NARROW RIBBON OF WEAK INSTABILITY JUST AHEAD OF THE FRONT...SO WILL MENTION ISOLATED THUNDER ACROSS PORTIONS OF THE WESTERN ADIRONDACKS. SOME BRIEF GUSTY WINDS WILL ALSO BE POSSIBLE WITH THE LINE OF SHOWERS/STORMS FOR THIS AREA...BUT THERE WILL NOT BE ENOUGH INSTABILITY TO SUSTAIN TALL ENOUGH UPDRAFTS TO PRODUCE STRONGER WINDS. MODELS INDICATE THE LINE OF SHOWERS WILL BE WEAKENING SOMEWHAT AS THEY MOVE EAST DURING THE LATE EVENING AND OVERNIGHT HOURS. SO WILL MAINLY MENTION CHANCE POPS FOR MUCH OF THE AREA WITH LIGHT QPF AMOUNTS. THE COLD FRONT AND ANY ASSOCIATED SHOWERS SHOULD CLEAR THE ENTIRE AREA BY DAYBREAK SUNDAY. WINDS WILL BECOME NORTHERLY BEHIND THE FRONT AND WILL BE NOTICEABLE ALONG WITH COOLER TEMPERATURES. HIGHS ARE ONLY EXPECTED TO BE IN THE 60S TO NEAR 70...WHICH IS NEAR NORMAL BUT MUCH COOLER THAN RECENT DAYS. CLOUDS WILL DECREASE THROUGHOUT THE DAY AS HIGH PRESSURE BUILDS SOUTHWARD ACROSS THE AREA. HIGH PRESSURE WILL SETTLE IN OVER THE REGION SUNDAY NIGHT INTO MONDAY MORNING...RESULTING IN CLEAR SKIES AND LIGHT WINDS. THESE CONDITIONS WILL ALLOW FOR THE COOLEST OVERNIGHT TEMPERATURES WE HAVE SEEN IN THREE MONTHS. LOWS ARE FORECAST TO BE IN THE UPPER 30S TO MID 40S...WITH PATCHY FROST POSSIBLE FOR SOME AREAS NORTH AND EAST OF ALBANY. THE LAST DAY ALBANY OFFICIALLY HAD A TEMPERATURE IN THE 40S WAS BACK ON JUNE 20TH...WHICH WAS 49 DEGREES THAT MORNING. TRANQUIL WEATHER WILL PERSIST MONDAY AND MONDAY NIGHT...WITH HIGH PRESSURE REMAINING IN CONTROL. TEMPERATURES LOOK TO BE CLOSE TO NORMAL. MONDAY NIGHT WILL LIKELY NOT BE AS COLD AS THE PREVIOUS NIGHT DUE TO SOME POSSIBLE ADDED CLOUD COVER AND A SLIGHT EASTERLY BREEZE...AS THE CENTER OF THE HIGH PRESSURE SYSTEM RETREATS TOWARDS THE CANADIAN MARITIMES. && .LONG TERM /TUESDAY THROUGH FRIDAY/... THE LONG TERM PERIOD STARTS OUT DRY AND SEASONABLE AS A LARGE RIDGE OF HIGH PRESSURE EXTENDS FROM THE OHIO VALLEY NORTHEASTWARD INTO THE NORTHEASTERN US. A WEAK COLD FRONT IS EXPECTED TO DROP SOUTHEAST FROM SOUTHERN CANADA THROUGH THE NORTHEAST ON WEDNESDAY AND STALL ACROSS THE MIDDLE ATLANTIC REGION ON THURSDAY. AT THIS TIME EXPECT THE FRONTAL PASSAGE WILL BE DRY WITH MODEL GUIDANCE INDICATING LITTLE IF ANY MOISTURE WITH THE FRONTAL BOUNDARY. FRIDAY AT THIS POINT IS A DIFFICULT FORECAST AS THE MODELS DIVERGE ON WHETHER OR NOT MOISTURE FROM THE SOUTH LIFTS NORTH WITH THE FRONTAL BOUNDARY STALLED JUST TO OUR SOUTH. AT THIS TIME THE GFS LIFTS MOISTURE NORTHWARD ACROSS OUR REGION ON FRIDAY WHILE THE ECMWF IS DRY WITH HIGH PRESSURE REMAINING IN CONTROL OF OUR WEATHER. FOR NOW WILL PLACE SLIGHT CHANCE POPS IN THE GRIDS FOR FRIDAY. TEMPERATURES FOR THE LONG TERM PERIOD WILL BE SEASONABLE TO SLIGHTLY BELOW NORMAL. EXPECT HIGHS TUESDAY TO BE IN THE MID 60S TO MID 70S WITH HIGHS ON WEDNESDAY AND THURSDAY IN THE UPPER 60S TO MID 70S AND HIGHS ON FRIDAY IN THE 60S TO AROUND 70 ALTHOUGH IT COULD BE COOLER IF THE GFS IS CORRECT. LOWS WILL BE IN THE 40S TO LOWER 50S TUESDAY NIGHT THROUGH THURSDAY NIGHT. && .AVIATION /15Z SATURDAY THROUGH WEDNESDAY/... FOR TODAY EXPECTING SOME HIGH CLOUDS TO STREAM IN AND EVENTUALLY MID CLOUDS THIS AFTERNOON TO MOVE IN AHEAD AN APPROACHING COLD FRONT. THIS BOUNDARY WILL USHER A MUCH COOLER AND MORE SEASONABLE AIR MASS INTO THE REGION WITH ITS PASSAGE TONIGHT. HAVE INCLUDED -SHRA FOR KGFL AFTER 03Z AND VCSH FOR KALB...KPSF AND KPOU BTWN 03Z AND 05Z AS SHOWERS WILL BE DIMINISHING IN COVERAGE AS THEY MOVE SOUTH AND EAST. CIGS WILL ALSO LOWER TO OVC035-050 BTWN 03Z AND 05Z. SKIES WILL THEN BECOME SCT035-045 LATE TONIGHT IN THE WAKE OF THE COLD FRONT. CALM WINDS WILL BECOME SOUTHERLY TODAY AS THE FLOW WILL PICK UP DURING THE DAY TO 8 TO 12 KNOTS WITH SOME 15-22 KTS EXPECTED AT KGFL...KPSF AND ESPECIALLY KALB DURING THE AFTERNOON. WINDS WILL REMAIN BTWN 08-12 KTS THIS EVENING BEFORE SHIFTING TO THE WEST- NORTHWEST WITH THE FRONTAL PASSAGE LATE TONIGHT. OUTLOOK... SUN-WED: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... A VERY WARM AIR MASS WILL PERSIST THROUGH TODAY WITH HIGH PRESSURE ALONG THE EAST COAST. HOWEVER...A COLD FRONT APPROACHING FROM THE GREAT LAKES WILL CROSS OUR REGION TONIGHT BRINGING SOME SHOWERS AND USHERING IN A COOLER AND MORE SEASONABLE AIR MASS FOR SUNDAY INTO EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITY VALUES TODAY WILL BE AROUND 45 TO 50 PERCENT...INCREASING TO MAXIMUM VALUES OF 85 TO 100 PERCENT TONIGHT. MIN RH VALUES ON SUNDAY ARE FORECAST TO BE BETWEEN 35 AND 45 PERCENT. WINDS TODAY WILL BE SOUTHERLY AROUND 10 TO 15 MPH...BECOMING NORTHWEST AT 5 TO 15 MPH TONIGHT AS A COLD FRONT PASSES THROUGH. WINDS ON SUNDAY WILL BECOME NORTHERLY AROUND 5 TO 15 MPH. && .HYDROLOGY... NO HYDROLOGIC CONCERNS THROUGH THE NEXT FIVE DAYS. DRY CONDITIONS WILL PERSIST THROUGH MUCH OF TODAY. A COLD FRONT WILL CROSS THE REGION FROM WEST TO EAST TONIGHT WITH MAINLY SCATTERED SHOWERS EXPECTED. SHOWERS WILL BE MORE NUMEROUS ACROSS THE WESTERN ADIRONDACKS WHERE ONE QUARTER TO ONE THIRD OF AN INCH OF RAINFALL IS POSSIBLE. ELSEWHERE GENERALLY A TENTH OF AN INCH OR LESS IS EXPECTED. THE RAINFALL WILL HAVE LITTLE...IF ANY IMPACT ON AREA RIVERS. DRY CONDITIONS RETURN FOR SUNDAY AND WILL LIKELY LAST THROUGH AT LEAST THE MIDDLE OF NEXT WEEK WITH ANOTHER AREA OF HIGH PRESSURE BUILDING IN. RIVER FLOWS WILL CONTINUE TO RECEDE INTO NEXT WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...JPV NEAR TERM...GJM/JPV SHORT TERM...JPV LONG TERM...11 AVIATION...11 FIRE WEATHER...JPV HYDROLOGY...JPV
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1002 AM EDT SAT SEP 19 2015 .SYNOPSIS... HIGH PRESSURE WILL REMAIN IN CONTROL TODAY...WITH A COLD FRONT BRINGING JUST A FEW SHOWERS LATE TONIGHT INTO EARLY SUNDAY. HIGH PRESSURE THEN BUILDS INTO NORTHERN NEW ENGLAND FOR MUCH OF NEXT WEEK. LOW PRESSURE WELL OFFSHORE TO THE SOUTH MAY BRING SHOWERS CLOSE TO THE ISLANDS TUESDAY...OTHERWISE DRY WEATHER THROUGH THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 10 AM UPDATE... ALLOWED THE DENSE FOG ADVISORY TO EXPIRE NATURALLY AS MOST LOCATIONS HAD LIFTED TO AT LEAST 0.5 MILES OR HIGHER. STILL SOME AREAS WHERE FOG IS HANGING IN...BUT VSBYS ALL SHOWING SIGNS OF RISING. OTHERWISE...FORECAST REQUIRED A BIT MORE MANUAL ADJUSTMENT THIS MORNING AS THE STRATUS DEC CONTINUES TO HOLD FAST AS OF 1O AM. SKIES WERE THE FIRST THING THAT NEEDED ADJUSTING. HOWEVER...THIS IS ALSO IMPACTING THE TEMPS...AND ARE LIKELY TO IMPACT THE HIGHS THIS AFTERNOON. GUIDANCE...EVEN IN THE SHORT TERM ARE NOT REALLY HANDLING THIS WELL. SO STARTED WITH A BASELINE OF 2M HRRR TEMPS COMBINED WITH OUR IN-HOUSE BIAS CORRECTED MAV. THIS PRESENTED A GOOD FOUNDATION BUT THEN MADE MANUAL EDITS FROM THERE BASED ON THE TIMING OF CLOUD COVER CLEARING. THE OVERALL FINAL NUMBERS ARE A BIT LOWER THAN PREVIOUS. PREVIOUS DISCUSSION... AFTER ANY EARLY MORNING FOG BURNS OFF...EXPECTING ANOTHER MOSTLY SUNNY...WARM DAY BEFORE A COLD FRONT MOVES THROUGH TONIGHT. HIGH TEMPERATURES ARE EXPECTED TO BE IN THE UPPER 70S TO LOWER 80S MOST LOCATIONS. SLIGHTLY COOLER TEMPERATURES EXPECTED ALONG THE SOUTH COAST WITH AN ONSHORE WIND. INCREASING DEWPOINTS WILL LEAD TO A MORE HUMID FEELING TO THE DAY...BUT IT SHOULD NOT FEEL OPPRESSIVE. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/... TONIGHT...LOW PRESSURE MOVES THROUGH QUEBEC BRINGING A COLD FRONT THROUGH SOUTHERN NEW ENGLAND. THERE IS ENOUGH MOISTURE AVAILABLE... AS INDICATED BY K INDICES...FOR SHOWERS TO DEVELOP. INSTABILITY AND MID LEVEL LAPSE RATES ARE LACKING SO NO THUNDER IS EXPECTED. NOT EXPECTING WIDESPREAD RAIN OVERNIGHT BUT SOME LOCATIONS WILL LIKELY HAVE A SHOWER OR TWO. DESPITE ABOVE NORMAL PWAT VALUES...RAINFALL AMOUNTS WILL BE LESS THAN A QUARTER INCH. NOT ENOUGH TO MAKE MUCH OF A DIFFERENCE IN THE RAINFALL DEFICIT. INCREASING CLOUDS...CHANCE OF SHOWERS...AND INCREASED DEWPOINTS... WILL COMBINE TO KEEP OVERNIGHT TEMPERATURES A BIT WARMER THAN PREVIOUS NIGHTS. THE ONLY EXCEPTION TO THIS MAY BE IN NORTHWESTERN MASSACHUSETTS WHERE COLD ADVECTION BEHIND THE FRONT MAY BEGIN BY THE EARLY MORNING HOURS. SUNDAY...MOST PRECIP SHOULD HAVE COME TO AN END BY SUNRISE SUNDAY MORNING. THERE IS A LOW PROBABILITY THAT A FEW SHOWERS MAY LINGER ON THE CAPE AND ISLANDS EARLY BEFORE THE FRONT PUSHES OFFSHORE. HIGH PRESSURE BUILDS INTO NORTHERN NEW ENGLAND BRINGING DRY WEATHER TO THE REGION. EXPECT STRONG COLD ADVECTION TO HOLD OFF UNTIL AFTER SUNSET SUNDAY SO MUCH OF THE DAY WILL BE PLEASANT WITH SUNNY SKIES AND MORE SEASONABLE TEMPERATURES. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... BIG PICTURE... UPPER TROUGH OVER THE GULF OF ALASKA WITH NEAR-ZONAL FLOW ACROSS THE PACIFIC NORTHWEST AND CANADA. SOUTHERN NEW ENGLAND REMAINS SOUTH OF THIS NORTHERN JET THROUGH THE FORECAST PERIOD. SOUTHERN STREAM UPPER LOW LOITERS OVER THE SOUTHEAST USA THROUGH THE WEEK. THE GFS EJECTS THIS LOW TOWARD NEW ENGLAND AT THE END OF THE WEEK WHILE THE ECMWF MOVES IT SOUTHWEST TOWARD THE GULF OF MEXICO. THE LARGE SCALE PATTERN IS DRY AND WARM WITH 500 MB CONTOURS MOSTLY ABOVE NORMAL. HOWEVER A LOW LEVEL EAST/NORTHEAST FLOW WOULD BUFFER SURFACE TEMPS SEVERAL DEGREES...CLOSER TO NORMAL OR A LITTLE BELOW. THE DAILIES... SUNDAY NIGHT-MONDAY... HIGH PRESSURE BUILDS OVER NORTHERN NEW ENGLAND WITH SHORTWAVE RIDGE ALOFT. THIS SHOULD PROVIDE GENERAL SUBSIDENCE. POSITIONING OF THE HIGH CENTER WILL BRING A NORTHEAST FLOW ACROSS SOUTHERN NEW ENGLAND...STRONGEST NEAR THE EAST MASSACHUSETTS SHORE. THIS SUGGESTS MOSTLY CLEAR SKIES WITH LIGHT WIND INLAND AND A BUFFERING EAST/NORTHEAST WIND FLOW NEAR THE EASTERN SHORE. RADIATIONAL COOLING SUNDAY NIGHT SHOULD BRING SFC TEMPS TO NEAR THE DEW POINT. INLAND DEWS WILL BE IN THE UPPER 30S TO LOWER 40S...COASTAL DEWS IN THE MID 40S TO LOWER 50S. EAST FLOW WILL LIMIT MIXING DEPTHS...BASED ON TEMPS AT 900 MB THIS WOULD SUPPORT MONDAY MAX TEMPS IN THE MID AND UPPER 60S NEAR THE SHORE AND LOWER 70S INLAND. TUESDAY THROUGH THURSDAY... HIGH PRESSURE IN CONTROL MUCH OF THE TIME OVER NEW ENGLAND. A WEAK SHORTWAVE MOVES THROUGH THE REGION WEDNESDAY WITH VERY LIMITED MOISTURE NOTED ON THE MODELS. MAYBE ENOUGH FOR A PERIOD OF CLOUDS...BUT NO PCPN. FRIDAY...THE ECMWF BUILDS CANADIAN HIGH PRESSURE OVER THE REGION WITH A NORTHWEST UPPER FLOW. THE GFS IS MORE SHALLOW WITH A SHORTWAVE OVER QUEBEC FRIDAY AND FRIDAY NIGHT...ALSO FARTHER NORTH WITH SOUTHERN STREAM UPPER LOW MOVING THROUGH CAROLINAS INTO DELMARVA AREA. THIS BRINGS SHOWERS FARTHER NORTH ON FRIDAY AS WELL AS THE LEFT FRONT QUADRANT OF ASSOCIATED UPPER JET. THE ECMWF SCENARIO IS FOR DRY WEATHER. THE GFS SCENARIO WOULD SUGGEST A CHANCE OF SHOWERS ON FRIDAY...BUT ITS SUDDEN APPEARANCE ON THIS RUN AND IN THE FINAL PERIOD OF THE FORECAST DOES NOT GENERATE A LOT OF CONFIDENCE. WE WILL GO WITH THE DRY ECMWF SCENARIO. && .AVIATION /14Z SATURDAY THROUGH WEDNESDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH SUNDAY/...HIGH CONFIDENCE. VFR. AREAS OF IFR/LIFR IN MORNING FOG...ESPECIALLY IN THE CT VALLEY AND IN RI/SOUTHEAST MASS. BUT THIS FOG WILL THIN THROUGH THE MORNING. BRIEF MVFR CONDITIONS POSSIBLE IN SCT SHRA TONIGHT. SURFACE WINDS SHIFT FROM SOUTH TO NORTH ON SUNDAY AS A COLD FRONT MOVES THROUGH. KBOS TERMINAL...HIGH CONFIDENCE IN TAF. KBDL TERMINAL...HIGH CONFIDENCE IN TAF. OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...MODERATE TO HIGH CONFIDENCE. VFR THROUGH THE PERIOD. NORTHEAST TO EAST WINDS ARE EXPECTED MONDAY WITH GUSTS 20 TO 25 KNOTS MAINLY ACROSS CAPE COD AND ISLANDS. EAST TO NORTHEAST FLOW CONTINUES THROUGH MIDWEEK WITH LIGHTER WINDS IN THE INTERIOR. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH SUNDAY/...HIGH CONFIDENCE. FOG MAY LIMIT VISIBILITIES THIS MORNING...BUT SHOULD THIN DURING THE MORNING HOURS. THEN HIGH PRESSURE OVER THE WATERS WILL BRING LIGHT WINDS AND CALM SEAS THROUGH SUNDAY MORNING. WINDS AND SEAS BUILD SUNDAY AFTERNOON AS A COLD FRONT CROSSES THE WATERS. SCA CONDITIONS MAY OCCUR BY SUNDAY EVENING. OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...HIGH CONFIDENCE. HIGH PRESSURE BUILDS OVER NORTHERN NEW ENGLAND WITH EAST TO NORTHEAST WINDS ACROSS THE MASS AND RI COASTAL WATERS. LOW LEVEL FLOW SUPPORTS WINDS 20 TO 25 KNOTS SUNDAY NIGHT AND MONDAY THEN DIMINISHING. THESE WINDS WILL MAINTAIN 5 TO 7 FOOT SEAS ON THE OUTER WATERS AND MASS BAY...POSSIBLY CAPE COD BAY. WINDS DIMINISH THROUGH MIDWEEK WHILE SEAS SUBSIDE VERY SLOWLY. SMALL CRAFT ADVISORY CONTINUES THROUGH AT LEAST MONDAY...AND POSSIBLY LINGERING SMALL CRAFTS FOR SEAS ON THE OUTER WATERS THROUGH MIDWEEK. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. RI...NONE. MARINE...NONE. && $$ SYNOPSIS...WTB/RLG NEAR TERM...DOODY/RLG SHORT TERM...RLG LONG TERM...WTB AVIATION...WTB/RLG MARINE...WTB/RLG
AREA FORECAST DISCUSSION
NWS ALBANY NY
640 AM EDT SAT SEP 19 2015 .SYNOPSIS... A VERY WARM AIR MASS WILL PERSIST THROUGH TODAY WITH HIGH PRESSURE ALONG THE EAST COAST. HOWEVER...A COLD FRONT APPROACHING FROM THE GREAT LAKES WILL CROSS OUR REGION TONIGHT BRINGING SOME SHOWERS AND USHERING IN A COOLER AND MORE SEASONABLE AIR MASS FOR SUNDAY INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 640 AM EDT...HIGH LEVEL CLOUDS ALREADY STARTING TO THIN OUT AS EXPECTED AND WILL CONTINUE THROUGH THIS MORNING LEAVING MOSTLY SUNNY SKIES FOR MUCH OF THE AREA INTO THE AFTERNOON. ADDITIONAL CLOUDS INCREASE FROM THE WEST ASSOCIATED WITH A COLD FRONT APPROACHING FROM THE GREAT LAKES LATE IN THE DAY. ONE MORE WARM DAY IS EXPECTED...WITH SUNSHINE AND A SOUTHERLY FLOW RESULTING IN HIGH TEMPS IN THE UPPER 70S TO LOWER 80S. MOST OF THE AREA SHOULD REMAIN DRY THROUGH THE DAYLIGHT HOURS. HOWEVER...CHANCES FOR SHOWERS WILL START TO INCREASE FOR THE WESTERN ADIRONDACKS/MOHAWK VALLEY LATE IN THE DAY AS THE COLD FRONT MOVES INTO WESTERN NY. BASED ON TIMING FROM HRRR AND LOCAL HI-RES WRF...WILL ONLY MENTION 20-30 POPS FOR HERKIMER/HAMILTON COUNTIES THROUGH 6 PM TODAY. THE BULK OF THE SHOWERS WILL ARRIVE AFTER DARK. && .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/... SHOWERS WILL BE MOVING INTO WESTERN PORTIONS OF THE AREA EARLY THIS EVENING...PRECEDING A COLD FRONT PUSHING EASTWARD ACROSS NY STATE. MODELS INDICATING A NARROW RIBBON OF WEAK INSTABILITY JUST AHEAD OF THE FRONT...SO WILL MENTION ISOLATED THUNDER ACROSS PORTIONS OF THE WESTERN ADIRONDACKS. SOME BRIEF GUSTY WINDS WILL ALSO BE POSSIBLE WITH THE LINE OF SHOWERS/STORMS FOR THIS AREA...BUT THERE WILL NOT BE ENOUGH INSTABILITY TO SUSTAIN TALL ENOUGH UPDRAFTS TO PRODUCE STRONGER WINDS. MODELS INDICATE THE LINE OF SHOWERS WILL BE WEAKENING SOMEWHAT AS THEY MOVE EAST DURING THE LATE EVENING AND OVERNIGHT HOURS. SO WILL MAINLY MENTION CHANCE POPS FOR MUCH OF THE AREA WITH LIGHT QPF AMOUNTS. THE COLD FRONT AND ANY ASSOCIATED SHOWERS SHOULD CLEAR THE ENTIRE AREA BY DAYBREAK SUNDAY. WINDS WILL BECOME NORTHERLY BEHIND THE FRONT AND WILL BE NOTICEABLE ALONG WITH COOLER TEMPERATURES. HIGHS ARE ONLY EXPECTED TO BE IN THE 60S TO NEAR 70...WHICH IS NEAR NORMAL BUT MUCH COOLER THAN RECENT DAYS. CLOUDS WILL DECREASE THROUGHOUT THE DAY AS HIGH PRESSURE BUILDS SOUTHWARD ACROSS THE AREA. HIGH PRESSURE WILL SETTLE IN OVER THE REGION SUNDAY NIGHT INTO MONDAY MORNING...RESULTING IN CLEAR SKIES AND LIGHT WINDS. THESE CONDITIONS WILL ALLOW FOR THE COOLEST OVERNIGHT TEMPERATURES WE HAVE SEEN IN THREE MONTHS. LOWS ARE FORECAST TO BE IN THE UPPER 30S TO MID 40S...WITH PATCHY FROST POSSIBLE FOR SOME AREAS NORTH AND EAST OF ALBANY. THE LAST DAY ALBANY OFFICIALLY HAD A TEMPERATURE IN THE 40S WAS BACK ON JUNE 20TH...WHICH WAS 49 DEGREES THAT MORNING. TRANQUIL WEATHER WILL PERSIST MONDAY AND MONDAY NIGHT...WITH HIGH PRESSURE REMAINING IN CONTROL. TEMPERATURES LOOK TO BE CLOSE TO NORMAL. MONDAY NIGHT WILL LIKELY NOT BE AS COLD AS THE PREVIOUS NIGHT DUE TO SOME POSSIBLE ADDED CLOUD COVER AND A SLIGHT EASTERLY BREEZE...AS THE CENTER OF THE HIGH PRESSURE SYSTEM RETREATS TOWARDS THE CANADIAN MARITIMES. && .LONG TERM /TUESDAY THROUGH FRIDAY/... THE LONG TERM PERIOD STARTS OUT DRY AND SEASONABLE AS A LARGE RIDGE OF HIGH PRESSURE EXTENDS FROM THE OHIO VALLEY NORTHEASTWARD INTO THE NORTHEASTERN US. A WEAK COLD FRONT IS EXPECTED TO DROP SOUTHEAST FROM SOUTHERN CANADA THROUGH THE NORTHEAST ON WEDNESDAY AND STALL ACROSS THE MIDDLE ATLANTIC REGION ON THURSDAY. AT THIS TIME EXPECT THE FRONTAL PASSAGE WILL BE DRY WITH MODEL GUIDANCE INDICATING LITTLE IF ANY MOISTURE WITH THE FRONTAL BOUNDARY. FRIDAY AT THIS POINT IS A DIFFICULT FORECAST AS THE MODELS DIVERGE ON WHETHER OR NOT MOISTURE FROM THE SOUTH LIFTS NORTH WITH THE FRONTAL BOUNDARY STALLED JUST TO OUR SOUTH. AT THIS TIME THE GFS LIFTS MOISTURE NORTHWARD ACROSS OUR REGION ON FRIDAY WHILE THE ECMWF IS DRY WITH HIGH PRESSURE REMAINING IN CONTROL OF OUR WEATHER. FOR NOW WILL PLACE SLIGHT CHANCE POPS IN THE GRIDS FOR FRIDAY. TEMPERATURES FOR THE LONG TERM PERIOD WILL BE SEASONABLE TO SLIGHTLY BELOW NORMAL. EXPECT HIGHS TUESDAY TO BE IN THE MID 60S TO MID 70S WITH HIGHS ON WEDNESDAY AND THURSDAY IN THE UPPER 60S TO MID 70S AND HIGHS ON FRIDAY IN THE 60S TO AROUND 70 ALTHOUGH IT COULD BE COOLER IF THE GFS IS CORRECT. LOWS WILL BE IN THE 40S TO LOWER 50S TUESDAY NIGHT THROUGH THURSDAY NIGHT. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... FOR TODAY EXPECTING SOME HIGH CLOUDS TO STREAM IN AND EVENTUALLY MID CLOUDS THIS AFTERNOON TO MOVE IN AHEAD AN APPROACHING COLD FRONT. THIS BOUNDARY WILL USHER A MUCH COOLER AND MORE SEASONABLE AIR MASS INTO THE REGION WITH ITS PASSAGE TONIGHT. HAVE INCLUDED -SHRA FOR KGFL AFTER 03Z AND VCSH FOR KALB...KPSF AND KPOU BTWN 03Z AND 05Z AS SHOWERS WILL BE DIMINISHING IN COVERAGE AS THEY MOVE SOUTH AND EAST. CIGS WILL ALSO LOWER TO OVC035-050 BTWN 03Z AND 05Z. SKIES WILL THEN BECOME SCT035-045 LATE TONIGHT IN THE WAKE OF THE COLD FRONT. CALM WINDS WILL BECOME SOUTHERLY TODAY AS THE FLOW WILL PICK UP DURING THE DAY TO 8 TO 12 KNOTS WITH SOME 15-22 KTS EXPECTED AT KGFL...KPSF AND ESPECIALLY KALB DURING THE AFTERNOON. WINDS WILL REMAIN BTWN 08-12 KTS THIS EVENING BEFORE SHIFTING TO THE WEST- NORTHWEST WITH THE FRONTAL PASSAGE LATE TONIGHT. OUTLOOK... SUN-WED: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... A VERY WARM AIR MASS WILL PERSIST THROUGH TODAY WITH HIGH PRESSURE ALONG THE EAST COAST. HOWEVER...A COLD FRONT APPROACHING FROM THE GREAT LAKES WILL CROSS OUR REGION TONIGHT BRINGING SOME SHOWERS AND USHERING IN A COOLER AND MORE SEASONABLE AIR MASS FOR SUNDAY INTO EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITY VALUES TODAY WILL BE AROUND 45 TO 50 PERCENT...INCREASING TO MAXIMUM VALUES OF 85 TO 100 PERCENT TONIGHT. MIN RH VALUES ON SUNDAY ARE FORECAST TO BE BETWEEN 35 AND 45 PERCENT. WINDS TODAY WILL BE SOUTHERLY AROUND 10 TO 15 MPH...BECOMING NORTHWEST AT 5 TO 15 MPH TONIGHT AS A COLD FRONT PASSES THROUGH. WINDS ON SUNDAY WILL BECOME NORTHERLY AROUND 5 TO 15 MPH. && .HYDROLOGY... NO HYDROLOGIC CONCERNS THROUGH THE NEXT FIVE DAYS. DRY CONDITIONS WILL PERSIST THROUGH MUCH OF TODAY. A COLD FRONT WILL CROSS THE REGION FROM WEST TO EAST TONIGHT WITH MAINLY SCATTERED SHOWERS EXPECTED. SHOWERS WILL BE MORE NUMEROUS ACROSS THE WESTERN ADIRONDACKS WHERE ONE QUARTER TO ONE THIRD OF AN INCH OF RAINFALL IS POSSIBLE. ELSEWHERE GENERALLY A TENTH OF AN INCH OR LESS IS EXPECTED. THE RAINFALL WILL HAVE LITTLE...IF ANY IMPACT ON AREA RIVERS. DRY CONDITIONS RETURN FOR SUNDAY AND WILL LIKELY LAST THROUGH AT LEAST THE MIDDLE OF NEXT WEEK WITH ANOTHER AREA OF HIGH PRESSURE BUILDING IN. RIVER FLOWS WILL CONTINUE TO RECEDE INTO NEXT WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...JPV NEAR TERM...JPV SHORT TERM...JPV LONG TERM...11 AVIATION...11 FIRE WEATHER...JPV HYDROLOGY...JPV
AREA FORECAST DISCUSSION
NWS ALBANY NY
620 AM EDT SAT SEP 19 2015 .SYNOPSIS... A VERY WARM AIR MASS WILL PERSIST THROUGH TODAY WITH HIGH PRESSURE ALONG THE EAST COAST. HOWEVER...A COLD FRONT APPROACHING FROM THE GREAT LAKES WILL CROSS OUR REGION TONIGHT BRINGING SOME SHOWERS AND USHERING IN A COOLER AND MORE SEASONABLE AIR MASS FOR SUNDAY INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 412 AM EDT...SOME HIGH LEVEL CLOUDS HAVE MOVED INTO THE AREA EARLY THIS MORNING...WHICH ARE DEBRIS CLOUDS FROM SHOWERS THAT FELL APART TO THE WEST OF OUR REGION YESTERDAY. THE CLOUDS HAVE NOT PREVENTED TEMPERATURES FROM FALLING THOUGH...WITH 50S ACROSS MUCH OF THE AREA. THE ONLY EXCEPTION IS IN THE CAPITAL DISTRICT WHERE A SOUTHERLY BREEZE HAS KEPT TEMPS IN THE LOWER TO MID 60S. PATCHY FOG IS ALSO OCCURRING...BUT THE COVERAGE APPEARS TO BE LESS THAN YESTERDAY MORNING. CLOUDS SHOULD TEND TO THIN OUT SOMEWHAT LATER THIS MORNING...BEFORE ADDITIONAL CLOUDS INCREASE FROM THE WEST ASSOCIATED WITH A COLD FRONT APPROACHING FROM THE GREAT LAKES. ONE MORE WARM DAY IS EXPECTED...WITH SUNSHINE AND A SOUTHERLY FLOW RESULTING IN HIGH TEMPS IN THE UPPER 70S TO LOWER 80S. MOST OF THE AREA SHOULD REMAIN DRY THROUGH THE DAYLIGHT HOURS. HOWEVER...CHANCES FOR SHOWERS WILL START TO INCREASE FOR THE WESTERN ADIRONDACKS/MOHAWK VALLEY LATE IN THE DAY AS THE COLD FRONT MOVES INTO WESTERN NY. BASED ON TIMING FROM HRRR AND LOCAL HI-RES WRF...WILL ONLY MENTION 20-30 POPS FOR HERKIMER/HAMILTON COUNTIES THROUGH 6 PM TODAY. THE BULK OF THE SHOWERS WILL ARRIVE TONIGHT. && .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/... SHOWERS WILL BE MOVING INTO WESTERN PORTIONS OF THE AREA EARLY THIS EVENING...PRECEDING A COLD FRONT PUSHING EASTWARD ACROSS NY STATE. MODELS INDICATING A NARROW RIBBON OF WEAK INSTABILITY JUST AHEAD OF THE FRONT...SO WILL MENTION ISOLATED THUNDER ACROSS PORTIONS OF THE WESTERN ADIRONDACKS. SOME BRIEF GUSTY WINDS WILL ALSO BE POSSIBLE WITH THE LINE OF SHOWERS/STORMS FOR THIS AREA...BUT THERE WILL NOT BE ENOUGH INSTABILITY TO SUSTAIN TALL ENOUGH UPDRAFTS TO PRODUCE STRONGER WINDS. MODELS INDICATE THE LINE OF SHOWERS WILL BE WEAKENING SOMEWHAT AS THEY MOVE EAST DURING THE LATE EVENING AND OVERNIGHT HOURS. SO WILL MAINLY MENTION CHANCE POPS FOR MUCH OF THE AREA WITH LIGHT QPF AMOUNTS. THE COLD FRONT AND ANY ASSOCIATED SHOWERS SHOULD CLEAR THE ENTIRE AREA BY DAYBREAK SUNDAY. WINDS WILL BECOME NORTHERLY BEHIND THE FRONT AND WILL BE NOTICEABLE ALONG WITH COOLER TEMPERATURES. HIGHS ARE ONLY EXPECTED TO BE IN THE 60S TO NEAR 70...WHICH IS NEAR NORMAL BUT MUCH COOLER THAN RECENT DAYS. CLOUDS WILL DECREASE THROUGHOUT THE DAY AS HIGH PRESSURE BUILDS SOUTHWARD ACROSS THE AREA. HIGH PRESSURE WILL SETTLE IN OVER THE REGION SUNDAY NIGHT INTO MONDAY MORNING...RESULTING IN CLEAR SKIES AND LIGHT WINDS. THESE CONDITIONS WILL ALLOW FOR THE COOLEST OVERNIGHT TEMPERATURES WE HAVE SEEN IN THREE MONTHS. LOWS ARE FORECAST TO BE IN THE UPPER 30S TO MID 40S...WITH PATCHY FROST POSSIBLE FOR SOME AREAS NORTH AND EAST OF ALBANY. THE LAST DAY ALBANY OFFICIALLY HAD A TEMPERATURE IN THE 40S WAS BACK ON JUNE 20TH...WHICH WAS 49 DEGREES THAT MORNING. TRANQUIL WEATHER WILL PERSIST MONDAY AND MONDAY NIGHT...WITH HIGH PRESSURE REMAINING IN CONTROL. TEMPERATURES LOOK TO BE CLOSE TO NORMAL. MONDAY NIGHT WILL LIKELY NOT BE AS COLD AS THE PREVIOUS NIGHT DUE TO SOME POSSIBLE ADDED CLOUD COVER AND A SLIGHT EASTERLY BREEZE...AS THE CENTER OF THE HIGH PRESSURE SYSTEM RETREATS TOWARDS THE CANADIAN MARITIMES. && .LONG TERM /TUESDAY THROUGH FRIDAY/... THE LONG TERM PERIOD STARTS OUT DRY AND SEASONABLE AS A LARGE RIDGE OF HIGH PRESSURE EXTENDS FROM THE OHIO VALLEY NORTHEASTWARD INTO THE NORTHEASTERN US. A WEAK COLD FRONT IS EXPECTED TO DROP SOUTHEAST FROM SOUTHERN CANADA THROUGH THE NORTHEAST ON WEDNESDAY AND STALL ACROSS THE MIDDLE ATLANTIC REGION ON THURSDAY. AT THIS TIME EXPECT THE FRONTAL PASSAGE WILL BE DRY WITH MODEL GUIDANCE INDICATING LITTLE IF ANY MOISTURE WITH THE FRONTAL BOUNDARY. FRIDAY AT THIS POINT IS A DIFFICULT FORECAST AS THE MODELS DIVERGE ON WHETHER OR NOT MOISTURE FROM THE SOUTH LIFTS NORTH WITH THE FRONTAL BOUNDARY STALLED JUST TO OUR SOUTH. AT THIS TIME THE GFS LIFTS MOISTURE NORTHWARD ACROSS OUR REGION ON FRIDAY WHILE THE ECMWF IS DRY WITH HIGH PRESSURE REMAINING IN CONTROL OF OUR WEATHER. FOR NOW WILL PLACE SLIGHT CHANCE POPS IN THE GRIDS FOR FRIDAY. TEMPERATURES FOR THE LONG TERM PERIOD WILL BE SEASONABLE TO SLIGHTLY BELOW NORMAL. EXPECT HIGHS TUESDAY TO BE IN THE MID 60S TO MID 70S WITH HIGHS ON WEDNESDAY AND THURSDAY IN THE UPPER 60S TO MID 70S AND HIGHS ON FRIDAY IN THE 60S TO AROUND 70 ALTHOUGH IT COULD BE COOLER IF THE GFS IS CORRECT. LOWS WILL BE IN THE 40S TO LOWER 50S TUESDAY NIGHT THROUGH THURSDAY NIGHT. && .AVIATION /10Z SATURDAY THROUGH WEDNESDAY/... FOR TODAY EXPECTING SOME HIGH CLOUDS TO STREAM IN AND EVENTUALLY MID CLOUDS THIS AFTERNOON TO MOVE IN AHEAD AN APPROACHING COLD FRONT. THIS BOUNDARY WILL USHER A MUCH COOLER AND MORE SEASONABLE AIR MASS INTO THE REGION WITH ITS PASSAGE TONIGHT. HAVE INCLUDED -SHRA FOR KGFL AFTER 03Z AND VCSH FOR KALB...KPSF AND KPOU BTWN 03Z AND 05Z AS SHOWERS WILL BE DIMINISHING IN COVERAGE AS THEY MOVE SOUTH AND EAST. CIGS WILL ALSO LOWER TO OVC035-050 BTWN 03Z AND 05Z. SKIES WILL THEN BECOME SCT035-045 LATE TONIGHT IN THE WAKE OF THE COLD FRONT. CALM WINDS WILL BECOME SOUTHERLY TODAY AS THE FLOW WILL PICK UP DURING THE DAY TO 8 TO 12 KNOTS WITH SOME 15-22 KTS EXPECTED AT KGFL...KPSF AND ESPECIALLY KALB DURING THE AFTERNOON. WINDS WILL REMAIN BTWN 08-12 KTS THIS EVENING BEFORE SHIFTING TO THE WEST- NORTHWEST WITH THE FRONTAL PASSAGE LATE TONIGHT. OUTLOOK... SUN-WED: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... A VERY WARM AIR MASS WILL PERSIST THROUGH TODAY WITH HIGH PRESSURE ALONG THE EAST COAST. HOWEVER...A COLD FRONT APPROACHING FROM THE GREAT LAKES WILL CROSS OUR REGION TONIGHT BRINGING SOME SHOWERS AND USHERING IN A COOLER AND MORE SEASONABLE AIR MASS FOR SUNDAY INTO EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITY VALUES TODAY WILL BE AROUND 45 TO 50 PERCENT...INCREASING TO MAXIMUM VALUES OF 85 TO 100 PERCENT TONIGHT. MIN RH VALUES ON SUNDAY ARE FORECAST TO BE BETWEEN 35 AND 45 PERCENT. WINDS TODAY WILL BE SOUTHERLY AROUND 10 TO 15 MPH...BECOMING NORTHWEST AT 5 TO 15 MPH TONIGHT AS A COLD FRONT PASSES THROUGH. WINDS ON SUNDAY WILL BECOME NORTHERLY AROUND 5 TO 15 MPH. && .HYDROLOGY... NO HYDROLOGIC CONCERNS THROUGH THE NEXT FIVE DAYS. DRY CONDITIONS WILL PERSIST THROUGH MUCH OF TODAY. A COLD FRONT WILL CROSS THE REGION FROM WEST TO EAST TONIGHT WITH MAINLY SCATTERED SHOWERS EXPECTED. SHOWERS WILL BE MORE NUMEROUS ACROSS THE WESTERN ADIRONDACKS WHERE ONE QUARTER TO ONE THIRD OF AN INCH OF RAINFALL IS POSSIBLE. ELSEWHERE GENERALLY A TENTH OF AN INCH OR LESS IS EXPECTED. THE RAINFALL WILL HAVE LITTLE...IF ANY IMPACT ON AREA RIVERS. DRY CONDITIONS RETURN FOR SUNDAY AND WILL LIKELY LAST THROUGH AT LEAST THE MIDDLE OF NEXT WEEK WITH ANOTHER AREA OF HIGH PRESSURE BUILDING IN. RIVER FLOWS WILL CONTINUE TO RECEDE INTO NEXT WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...JPV NEAR TERM...JPV SHORT TERM...JPV LONG TERM...11 AVIATION...11 FIRE WEATHER...JPV HYDROLOGY...JPV
AREA FORECAST DISCUSSION
NWS ALBANY NY
412 AM EDT SAT SEP 19 2015 .SYNOPSIS... A VERY WARM AIR MASS WILL PERSIST THROUGH TODAY WITH HIGH PRESSURE ALONG THE EAST COAST. HOWEVER...A COLD FRONT APPROACHING FROM THE GREAT LAKES WILL CROSS OUR REGION TONIGHT BRINGING SOME SHOWERS AND USHERING IN A COOLER AND MORE SEASONABLE AIR MASS FOR SUNDAY INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 412 AM EDT...SOME HIGH LEVEL CLOUDS HAVE MOVED INTO THE AREA EARLY THIS MORNING...WHICH ARE DEBRIS CLOUDS FROM SHOWERS THAT FELL APART TO THE WEST OF OUR REGION YESTERDAY. THE CLOUDS HAVE NOT PREVENTED TEMPERATURES FROM FALLING THOUGH...WITH 50S ACROSS MUCH OF THE AREA. THE ONLY EXCEPTION IS IN THE CAPITAL DISTRICT WHERE A SOUTHERLY BREEZE HAS KEPT TEMPS IN THE LOWER TO MID 60S. PATCHY FOG IS ALSO OCCURRING...BUT THE COVERAGE APPEARS TO BE LESS THAN YESTERDAY MORNING. CLOUDS SHOULD TEND TO THIN OUT SOMEWHAT LATER THIS MORNING...BEFORE ADDITIONAL CLOUDS INCREASE FROM THE WEST ASSOCIATED WITH A COLD FRONT APPROACHING FROM THE GREAT LAKES. ONE MORE WARM DAY IS EXPECTED...WITH SUNSHINE AND A SOUTHERLY FLOW RESULTING IN HIGH TEMPS IN THE UPPER 70S TO LOWER 80S. MOST OF THE AREA SHOULD REMAIN DRY THROUGH THE DAYLIGHT HOURS. HOWEVER...CHANCES FOR SHOWERS WILL START TO INCREASE FOR THE WESTERN ADIRONDACKS/MOHAWK VALLEY LATE IN THE DAY AS THE COLD FRONT MOVES INTO WESTERN NY. BASED ON TIMING FROM HRRR AND LOCAL HI-RES WRF...WILL ONLY MENTION 20-30 POPS FOR HERKIMER/HAMILTON COUNTIES THROUGH 6 PM TODAY. THE BULK OF THE SHOWERS WILL ARRIVE TONIGHT. && .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/... SHOWERS WILL BE MOVING INTO WESTERN PORTIONS OF THE AREA EARLY THIS EVENING...PRECEDING A COLD FRONT PUSHING EASTWARD ACROSS NY STATE. MODELS INDICATING A NARROW RIBBON OF WEAK INSTABILITY JUST AHEAD OF THE FRONT...SO WILL MENTION ISOLATED THUNDER ACROSS PORTIONS OF THE WESTERN ADIRONDACKS. SOME BRIEF GUSTY WINDS WILL ALSO BE POSSIBLE WITH THE LINE OF SHOWERS/STORMS FOR THIS AREA...BUT THERE WILL NOT BE ENOUGH INSTABILITY TO SUSTAIN TALL ENOUGH UPDRAFTS TO PRODUCE STRONGER WINDS. MODELS INDICATE THE LINE OF SHOWERS WILL BE WEAKENING SOMEWHAT AS THEY MOVE EAST DURING THE LATE EVENING AND OVERNIGHT HOURS. SO WILL MAINLY MENTION CHANCE POPS FOR MUCH OF THE AREA WITH LIGHT QPF AMOUNTS. THE COLD FRONT AND ANY ASSOCIATED SHOWERS SHOULD CLEAR THE ENTIRE AREA BY DAYBREAK SUNDAY. WINDS WILL BECOME NORTHERLY BEHIND THE FRONT AND WILL BE NOTICEABLE ALONG WITH COOLER TEMPERATURES. HIGHS ARE ONLY EXPECTED TO BE IN THE 60S TO NEAR 70...WHICH IS NEAR NORMAL BUT MUCH COOLER THAN RECENT DAYS. CLOUDS WILL DECREASE THROUGHOUT THE DAY AS HIGH PRESSURE BUILDS SOUTHWARD ACROSS THE AREA. HIGH PRESSURE WILL SETTLE IN OVER THE REGION SUNDAY NIGHT INTO MONDAY MORNING...RESULTING IN CLEAR SKIES AND LIGHT WINDS. THESE CONDITIONS WILL ALLOW FOR THE COOLEST OVERNIGHT TEMPERATURES WE HAVE SEEN IN THREE MONTHS. LOWS ARE FORECAST TO BE IN THE UPPER 30S TO MID 40S...WITH PATCHY FROST POSSIBLE FOR SOME AREAS NORTH AND EAST OF ALBANY. THE LAST DAY ALBANY OFFICIALLY HAD A TEMPERATURE IN THE 40S WAS BACK ON JUNE 20TH...WHICH WAS 49 DEGREES THAT MORNING. TRANQUIL WEATHER WILL PERSIST MONDAY AND MONDAY NIGHT...WITH HIGH PRESSURE REMAINING IN CONTROL. TEMPERATURES LOOK TO BE CLOSE TO NORMAL. MONDAY NIGHT WILL LIKELY NOT BE AS COLD AS THE PREVIOUS NIGHT DUE TO SOME POSSIBLE ADDED CLOUD COVER AND A SLIGHT EASTERLY BREEZE...AS THE CENTER OF THE HIGH PRESSURE SYSTEM RETREATS TOWARDS THE CANADIAN MARITIMES. && .LONG TERM /TUESDAY THROUGH FRIDAY/... THE LONG TERM PERIOD STARTS OUT DRY AND SEASONABLE AS A LARGE RIDGE OF HIGH PRESSURE EXTENDS FROM THE OHIO VALLEY NORTHEASTWARD INTO THE NORTHEASTERN US. A WEAK COLD FRONT IS EXPECTED TO DROP SOUTHEAST FROM SOUTHERN CANADA THROUGH THE NORTHEAST ON WEDNESDAY AND STALL ACROSS THE MIDDLE ATLANTIC REGION ON THURSDAY. AT THIS TIME EXPECT THE FRONTAL PASSAGE WILL BE DRY WITH MODEL GUIDANCE INDICATING LITTLE IF ANY MOISTURE WITH THE FRONTAL BOUNDARY. FRIDAY AT THIS POINT IS A DIFFICULT FORECAST AS THE MODELS DIVERGE ON WHETHER OR NOT MOISTURE FROM THE SOUTH LIFTS NORTH WITH THE FRONTAL BOUNDARY STALLED JUST TO OUR SOUTH. AT THIS TIME THE GFS LIFTS MOISTURE NORTHWARD ACROSS OUR REGION ON FRIDAY WHILE THE ECMWF IS DRY WITH HIGH PRESSURE REMAINING IN CONTROL OF OUR WEATHER. FOR NOW WILL PLACE SLIGHT CHANCE POPS IN THE GRIDS FOR FRIDAY. TEMPERATURES FOR THE LONG TERM PERIOD WILL BE SEASONABLE TO SLIGHTLY BELOW NORMAL. EXPECT HIGHS TUESDAY TO BE IN THE MID 60S TO MID 70S WITH HIGHS ON WEDNESDAY AND THURSDAY IN THE UPPER 60S TO MID 70S AND HIGHS ON FRIDAY IN THE 60S TO AROUND 70 ALTHOUGH IT COULD BE COOLER IF THE GFS IS CORRECT. LOWS WILL BE IN THE 40S TO LOWER 50S TUESDAY NIGHT THROUGH THURSDAY NIGHT. && .AVIATION /08Z SATURDAY THROUGH WEDNESDAY/... HIGH PRESSURE WILL GRADUALLY SHIFT EASTWARD TONIGHT. CONDITIONS WILL ONCE AGAIN BE FAVORABLE FOR RADIATIONAL FOG OVERNIGHT ESPECIALLY AT KPSF AND KGFL WHERE THEY ARE PRONE TO THE DEVELOPMENT OF FOG...EXPECTING IFR CONDITIONS TO OCCUR. HAVE FOG MENTIONED IN KALB AND KPOU TAF HOWEVER IS LIMITED TO MIFG SINCE THEY HAVE NOT HAD ISSUES THAT LAST COUPLE OF NIGHTS/MORNINGS. EXPECTING SOME HIGH CLOUDS TO STREAM IN AND EVENTUALLY MID CLOUDS SATURDAY AFTERNOON TO MOVE IN AHEAD AN APPROACHING COLD FRONT. THIS BOUNDARY WILL USHER A MUCH COOLER AND MORE SEASONABLE AIR MASS INTO THE REGION WITH ITS PASSAGE SATURDAY NIGHT. HAVE INCLUDED -SHRA FOR KGFL AFTER 03Z AND VCSH FOR KALB...KPSF AND KPOU BTWN 03Z AND 05Z AS SHOWERS WILL BE DIMINISHING IN COVERAGE AS THEY MOVE SOUTH AND EAST. CIGS WILL ALSO LOWER TO OVC035-050 BTWN 03Z AND 05Z. CALM WINDS FOR THE OVERNIGHT WITH A SOUTHERLY FLOW DEVELOPING SATURDAY. THE FLOW WILL PICK UP DURING THE DAY TO 8 TO 12 KNOTS WITH SOME GUSTS EXPECTED AT KGFL...KPSF AND ESPECIALLY KALB DURING THE AFTERNOON. WINDS WILL REMAIN BTWN 08-12 KTS SATURDAY EVENING BEFORE SHIFTING TO THE NORTHWEST WITH THE FRONTAL PASSAGE LATE SATURDAY NIGHT. OUTLOOK... SAT NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. SUN-WED: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... A VERY WARM AIR MASS WILL PERSIST THROUGH TODAY WITH HIGH PRESSURE ALONG THE EAST COAST. HOWEVER...A COLD FRONT APPROACHING FROM THE GREAT LAKES WILL CROSS OUR REGION TONIGHT BRINGING SOME SHOWERS AND USHERING IN A COOLER AND MORE SEASONABLE AIR MASS FOR SUNDAY INTO EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITY VALUES TODAY WILL BE AROUND 45 TO 50 PERCENT...INCREASING TO MAXIMUM VALUES OF 85 TO 100 PERCENT TONIGHT. MIN RH VALUES ON SUNDAY ARE FORECAST TO BE BETWEEN 35 AND 45 PERCENT. WINDS TODAY WILL BE SOUTHERLY AROUND 10 TO 15 MPH...BECOMING NORTHWEST AT 5 TO 15 MPH TONIGHT AS A COLD FRONT PASSES THROUGH. WINDS ON SUNDAY WILL BECOME NORTHERLY AROUND 5 TO 15 MPH. && .HYDROLOGY... NO HYDROLOGIC CONCERNS THROUGH THE NEXT FIVE DAYS. DRY CONDITIONS WILL PERSIST THROUGH MUCH OF TODAY. A COLD FRONT WILL CROSS THE REGION FROM WEST TO EAST TONIGHT WITH MAINLY SCATTERED SHOWERS EXPECTED. SHOWERS WILL BE MORE NUMEROUS ACROSS THE WESTERN ADIRONDACKS WHERE ONE QUARTER TO ONE THIRD OF AN INCH OF RAINFALL IS POSSIBLE. ELSEWHERE GENERALLY A TENTH OF AN INCH OR LESS IS EXPECTED. THE RAINFALL WILL HAVE LITTLE...IF ANY IMPACT ON AREA RIVERS. DRY CONDITIONS RETURN FOR SUNDAY AND WILL LIKELY LAST THROUGH AT LEAST THE MIDDLE OF NEXT WEEK WITH ANOTHER AREA OF HIGH PRESSURE BUILDING IN. RIVER FLOWS WILL CONTINUE TO RECEDE INTO NEXT WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...JPV NEAR TERM...JPV SHORT TERM...JPV LONG TERM...11 AVIATION...IAA/11 FIRE WEATHER...JPV HYDROLOGY...JPV
AREA FORECAST DISCUSSION
NWS NEW YORK NY
206 AM EDT SAT SEP 19 2015 .SYNOPSIS... HIGH PRESSURE WILL GRADUALLY SLIDE EASTWARD THROUGH TODAY. A COLD FRONT WILL MOVES THROUGH LATE TONIGHT AND SUNDAY MORNING. HIGH PRESSURE WILL THEN BUILD TO THE NORTH EARLY NEXT WEEK...AND THEN TO THE NORTHEAST INTO THE MIDDLE OF THE WEEK...WHILE LOW PRESSURE MEANDERS OFF THE SOUTHEAST COAST. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... THE FORECAST REMAINS MAINLY ON TRACK. SOME PATCHY FOG HAS DEVELOPED ACROSS OF EASTERN LONG ISLAND AND EXPECT THIS TO CONTINUE THROUGH THE REST OF THE NIGHT WHERE BETTER COOLING TAKES PLACE. TEMPERATURES WERE SLIGHTLY ADJUSTED DOWN. OTHERWISE...NO OTHER REMARKABLE CHANGES MADE. THE HIGH WILL SLIDE E AND WEAKEN AS A COLD FRONT APPROACHES FROM THE WEST...AND AS LOW PRESSURE SLOWLY MOVES UP THE COAST. SKIES WILL BE CLEAR TONIGHT...AND WITH LIGHT ONSHORE FLOW CONTINUING...SHOULD SEE DEVELOPMENT OF FOG MAINLY AWAY FROM NYC LATE TONIGHT INTO EARLY SAT MORNING. LOWS IN THE VALLEYS OF ORANGE COUNTY AND THE LONG ISLAND PINE BARRENS WILL BE 55-60...WITH 60S ELSEWHERE. KEPT LOWS AROUND 60 ACROSS THE INTERIOR DESPITE AFTERNOON DEWPOINTS IN THE MID 50S SINCE AIR MASS WILL BE SLOWLY MOISTENING TONIGHT IN THE ONSHORE FLOW. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/... THE 12Z NAM AND NOW 12Z RAP ARE INDICATING AREA OF ISENTROPIC LIFT...WITH CLOUDS/SHOWERS...MOVING UP THE NJ COAST TOWARD WRN LONG ISLAND/CT AND SKIRTING NYC. NAM QPF OVERDONE BUT NOW THINK THIS IS AT LEAST WORTH A SLIGHT CHANCE MENTION FOR SAT MORNING. OTHERWISE...MOSTLY SUNNY SKIES ON SAT SHOULD LEAD TO HIGH TEMPS A COUPLE DEG HIGHER THAN COMPOSITE MOS GUIDANCE AND SIMILAR TO THOSE OF TODAY...WITH LOWER/MID 80S. A COLD FRONT WILL BEGIN TO MOVE ACROSS LATE SAT NIGHT. LIFT LOOKS WEAK AND DEEP MOISTURE IS LACKING...SO WILL CONTINUE TO CARRY SLIGHT TO LOW CHANCE POP. LOWS WILL BE MAINLY IN THE 60S. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... NORTHERN STREAM SHORTWAVE PIVOTS THROUGH SOUTHEASTERN CANADA ON SUNDAY/SUNDAY NIGHT. THEREAFTER MODELS IN FAIRLY GOOD AGREEMENT WITH A SPLIT FLOW DEVELOPING FOR EARLY TO MID NEXT WEEK AS SHORTWAVE ENERGY ENTERING THE PAC NW COAST DIGS THROUGH THE GREAT LAKES INTO THE SE US EARLY NEXT WEEK. PART OF THIS ENERGY SEPARATES ITSELF FROM THE NORTHERN STREAM AND CUTS OFF OVER THE SE US FOR THE MID TO LATE WEEK PERIOD...WHILE THE REST SWINGS THROUGH THE NORTHEAST DURING THE MIDWEEK PERIOD. SOME UNCERTAINTY IN THE FORECAST LIES IN THE INTERACTION OF THE DIGGING EASTERN TROUGH WITH PIECES OF SUB-TROPICAL ENERGY ROUNDING DOMINANT ATLANTIC RIDGING...AND HOW CLOSE TO THE COAST THIS MOISTURE/ENERGY MAY GET FOR MUCH OF THE WEEK. IN TERMS OF SENSIBLE WEATHER...A MOISTURE STARVED COLD FRONT WITH SHORTWAVE ENERGY WELL TO THE NW PASSES EAST OF THE REGION SUNDAY MORNING. A FEW LINGERING SHOWERS POSSIBLE SUNDAY MORNING...OTHERWISE A COOLER AND DRIER AIRMASS BEGINS ADVECTING INTO THE REGION ON BREEZY NORTHERLY FLOW ON SUNDAY. TEMPS SUNDAY SHOULD BE NEAR SEASONABLE. AS HIGH PRESSURE CONTINUES TO BUILD THROUGH AND EAST OF NEW ENGLAND EARLY TO MID NEXT WEEK...A BREEZY NE FLOW WILL PERSIST AND MAINTAIN A MAINLY DRY BUT SEASONABLY COOL CANADIAN MARITIMES AIRMASS OVER THE REGION. THE TIGHT GRADIENT WILL BE COURTESY OF A SERIES OF LOWS DRIFTING NE WELL OFF THE EAST COAST. AS MENTIONED BEFORE...UNCERTAINTY EXISTS ON EXACT EVOLUTION OF THESE OFFSHORE LOW/S INTO MIDWEEK...BUT NHC SEES A MEDIUM POTENTIAL FOR SOME SORT OF TROPICAL/SUB-TROPICAL DEVELOPMENT OVER THE NEXT 5 DAYS. THERE IS CURRENTLY A SLIGHT POTENTIAL FOR THE REGION TO AFFECTED BY SOME SHOWER ACTIVITY MIDWEEK AS THE EARLIER MENTIONED NORTHERN STREAM SHORTWAVE APPROACHES/SWINGS THROUGH...BUT THIS WILL ULTIMATELY BE DEPENDENT ON EVOLUTION OF THE OFFSHORE LOW PRESSURE/S AND STRENGTH OF UPPER CONFLUENCE/SURFACE RIDGING OVER THE NE. OTHERWISE...THE SAME MIDWEEK PATTERN COULD PERSIST THROUGH THE WEEK IN THE CONTINUED SPLIT FLOW REGIME...WITH THE REGION IN BETWEEN NORTHERN STREAM FLOW WELL TO THE NORTH...A BROAD CUTOFF LOW TO THE SOUTH...AND DOMINANT OFFSHORE RIDGING TO THE SE. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... HIGH PRESSURE REMAINS OFFSHORE TODAY AS A COLD FRONT APPROACHES FROM THE WEST. THIS REMAINS A CHALLENGING FORECAST WITH THE EXTENT OF FOG/STRATUS OVERNIGHT. AIRMASS REMAINS EXTREMELY DRY JUST OFF THE DECK WITH A LIGHT S/SW FLOW AT THE SFC. IN ADDITION...THERE ARE SOME HIGH LEVEL CLOUDS MOVING IN FROM THE WEST THAT COULD LIMIT THE COVERAGE. FOR NOW...WILL GO IFR AT KGON BASED ON CURRENT CONDITIONS...AND PATCHY MVFR ELSEWHERE OUTSIDE THE NYC TERMINALS. GUIDANCE VARIES WITH THE BEST CHANCE OF STRATUS/FOG ACROSS CT. .OUTLOOK FOR 06Z SATURDAY THROUGH WEDNESDAY... .SAT NIGHT...VFR. CHC OF WIDELY SCT SHOWERS WITH COLD FROPA. .SUN-TUE...MAINLY VFR. CHC SUB-VFR TUE. N-NE GUSTS 20-25KT POSSIBLE AT COASTAL TERMINALS. .WED...VFR. && .MARINE... CONDITIONS ACROSS THE AREA WATERS WILL REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THROUGH SATURDAY...AS HIGH PRESSURE MOVES OFFSHORE. SCA WIND GUSTS POSSIBLE SUNDAY AFTERNOON FOR ALL WATERS IN WAKE OF COLD FRONTAL PASSAGE...BUT BETTER POTENTIAL FOR SCA DEVELOPS SUNDAY NIGHT AND LIKELY THROUGH EARLY NEXT WEEK ESPECIALLY ON THE OCEAN WITH DEVELOPMENT OF A PERSISTENT E/NE FLOW. OCEAN SEAS COULD BUILD TO 6 TO 8 FT FOR EARLY NEXT WEEK...USUALLY UNDER-PREDICTED IN WNA GUIDANCE. WINDS MAY ALSO GUST CLOSE TO 25 KT DURING THIS TIME ACROSS ALL WATERS. && .FIRE WEATHER... FUEL MOISTURE LEVELS WILL LIKELY CONTINUE TO DECREASE THROUGH THE WEEKEND WITH THE UNSEASONABLY WARM AND DRY WEATHER. CURRENTLY KBDI VALUES ARE GREATER THAN 300 OVER A GOOD PORTION OF THE REGION. DEPENDING ON COVERAGE OF LIGHT RAINFALL WITH COLD FRONTAL PASSAGE SAT NIGHT/EARLY SUN...PREDECESSOR DRY CONDS WITH A GUSTY N FLOW AND LOW RH VALUES MAY RESULT IN AN ENHANCED FIRE WEATHER THREAT ON SUNDAY. && .HYDROLOGY... DRY CONDITIONS EXPECTED THROUGH SATURDAY WITH NO WIDESPREAD SIGNIFICANT PRECIPITATION EXPECTED THROUGH NEXT WEEK. && .TIDES/COASTAL FLOODING... THERE IS THE POSSIBILITY FOR MINOR COASTAL FLOODING DURING THE MON-FRI TIMEFRAME DUE TO THE FORECAST OF PROLONGED E-NE FLOW. POTENTIAL FOR IMPACTS APPEARS LOW FOR MON...BUT MAY INCREASE IN THE TYPICALLY VULNERABLE LOCALES FOR THE MID TO LATE WEEK PERIOD WITH GRADUALLY RISING ASTRONOMICAL HIGH TIDES. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS...GOODMAN/NV NEAR TERM...GOODMAN/JM SHORT TERM...GOODMAN LONG TERM...DW AVIATION...24 MARINE...GOODMAN/NV FIRE WEATHER... HYDROLOGY...GOODMAN/NV TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
917 PM EDT SUN SEP 20 2015 .UPDATE...WATER VAPOR IMAGERY AND MID AND LEVEL WINDS SHOW INCREASING MOISTURE FROM THE W WITH NEAR ZONAL FLOW. WEAK UPPER LEVEL SHORTWAVE NOTED OVER FL PANHANDLE MOVING EWD. BROAD MID AND UPPER LEVEL TROUGH IS ACROSS THE OHIO AND TN VALLEY WITH A SFC COLD FRONT ACROSS NC...NRN GA/AL/MS. WEAK PRES GRADIENT OVER OUR AREA TONIGHT WITH LIGHT WINDS WITH ONLY SCT/BKN HIGH CLOUDS EXPECTED AT TIMES AND OTHERWISE MOSTLY CLEAR CONDITIONS PREVAILING. ONLY SLIGHT CHANGES TO LOWER MIN TEMPS IN A FEW LOCATIONS FOR THE UPDATE BASED ON TRENDS AND LATEST MOS GUIDANCE. THE BOUNDARY LAYER THIS AFTN MIXED OUT WELL WITH DEWPOINTS IN SOME OF OUR NRN ZONES IN THE MID 50S...SO LOOKS LIKE FOG POTENTIAL IS PRETTY LOW AT THIS TIME. THIS THINKING IS ALSO REFLECTED IN SREF AND HRRR GUIDANCE WITH LITTLE TO NO FOG PREDICTED. && .AVIATION...PREVAILING VFR NEXT 24 HRS. LITTLE TO NO FOG EXPECTED LATE TONIGHT. && .MARINE...E TO SE WINDS NEAR 10 KT WILL TURN TO THE S BY MORNING. SEAS GENERALLY AROUND 3 FT. LITTLE TO NO CHANGE FOR THE CWF UPDATE. && .PRELIMINARY POINT TEMPS/POPS... AMG 65 89 69 85 / 0 20 10 30 SSI 72 83 72 79 / 0 10 10 40 JAX 68 90 72 82 / 0 10 10 40 SGJ 72 88 74 81 / 0 10 0 40 GNV 67 90 69 86 / 0 10 0 40 OCF 69 90 70 87 / 0 10 0 40 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && $$ SHASHY/PETERSON/WALKER
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
823 PM EDT SUN SEP 20 2015 .UPDATE (OVERNIGHT AND MONDAY)... 00Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUES TO SHOW A GENERALLY BENIGN UPPER LEVEL PATTERN ACROSS THE NATION THIS EVENING. STRONG ZONAL NORTHERN STREAM FLOW ARRIVES OVER THE PACIFIC NORTHWEST COAST...BEFORE SPLITTING INTO A NORTHERN BRANCH ACROSS CENTRAL CANADA...AND A SOUTHERN BRANCH DIVING INTO THE OHIO/TN VALLEYS. THE UPPER PATTERN OVER FLORIDA IS RATHER WEAK WITH NO SIGNIFICANT FEATURES OF NOTE IN THE HEIGHT FIELD. HOWEVER...WE DO FIND A DEEP SWATH OF VERY DRY AIR ALOFT ABOVE 10-15KFT. THE DRY AIR ALOFT WAS SAMPLED VERY WELL BY THE EVENING 00Z KTBW SOUNDING PROFILE ABOVE 700MB. THE PW WAS 1.3"...WHICH IS QUITE DRY FOR MID SEPTEMBER... RUNNING IN THE 25TH PERCENTILE OF VALUES. THIS DRY AIR IS DEEPEST AND MOST DEFINED OVER THE CENTRAL AND NORTHERN FL PENINSULA...WHERE BARELY AN ISOLATED SHOWER WAS ABLE TO TAKE ROOT THIS PAST AFTERNOON/EARLY EVENING. SCATTERED CONVECTION WAS ABLE TO FOCUS ALONG THE SEA-BREEZE...OVER FAR SOUTHERN FLORIDA...MAINLY SOUTH OF A LINE FROM FORT MYERS TO LAKE OKEECHOBEE. AS OF 8 PM EDT...WE CONTINUE TO SEE PERIODIC FLARE UPS OF SHOWERS OVER CHARLOTTE/LEE COUNTIES...AND MAY SEE A BRIEF SHOWER OVER THESE FAR SOUTHERN ZONES THROUGH ABOUT 2-3Z THIS EVENING. THEREAFTER...THE LOSS OF DIURNAL HEATING AND GENERAL HOSTILITY OF THE MID/UPPER LEVEL COLUMN TOWARD DEEP CONVECTION SHOULD SETTLE DOWN ANY UPDRAFTS AND RESULT IN A MAINLY DRY AND SEASONABLE MID SEPTEMBER NIGHT. THE SYNOPTIC PATTERN OVER THE STATE CHANGES LITTLE FOR THE DAYLIGHT HOURS OF MONDAY...AND HENCE THE FORECASTS WILL CHANGE LITTLE AS WELL. A SCT CUMULUS FIELD WILL DEVELOP REGION-WIDE BY THE EARLY AFTERNOON...BUT THE DRY AIR IN THE MID-LEVELS...AND RAPID ENTRAINMENT OF THE DRY AIR INTO ANY UPDRAFTS SHOULD KEEP THESE CUMULUS COLUMNS RATHER SHALLOW FOR MUCH OF THE REGION. ANY LATE DAY SHOWERS THAT CAN DEVELOP AFTER 19-20Z WILL BE CONFINED TO CHARLOTTE/LEE...AND PERHAPS SOUTHERN HIGHLANDS COUNTIES. EVEN FOR THESE LOCATIONS...ANY CONVECTION SHOULD BE ISOLATED IN NATURE...AND MUCH OF THE DAY ON MONDAY WILL BE DRY. && .AVIATION... VFR CONDITIONS PREVAIL ACROSS WEST-CENTRAL AND SOUTHWEST FLORIDA THIS EVENING. JUST A SLIGHT CHANCE OF A BRIEF SHOWER AT KFMY/KRSW THROUGH 02Z...BUT THE POTENTIAL FOR RESTRICTIONS ARE LOW ENOUGH TO KEEP MENTION OUT OF THE CURRENT TAF PACKAGE. MAY SEE A BRIEF PERIOD OF MVFR CIGS/VIS AROUND KLAL/KPGD CLOSE TO DAWN...BUT OTHERWISE...VFR CONDITIONS PREVAIL THROUGH THE DAYLIGHT HOURS MONDAY. SIMILAR TO SUNDAY...JUST A SLIGHT CHANCE OF A BRIEF LATE DAT SHOWER AT KFMY/KRSW. && .MARINE... THE GRADIENT ACROSS THE EASTERN GULF OF MEXICO REMAINS WEAK THROUGH TUESDAY...WITH LIGHT WINDS AND LOW WAVES IN THE FORECAST. HIGH PRESSURE BUILDING DOWN ACROSS THE EASTERN HALF OF THE NATION DURING THE MIDWEEK PERIOD WILL STRENGTHEN THE FLOW OUT OF THE NORTHEAST...WITH CONDITIONS APPROACHING CAUTIONARY LEVELS BY WEDNESDAY AND THURSDAY. && .PRELIMINARY POINT TEMPS/POPS... TPA 76 91 75 89 / 10 0 10 20 FMY 75 91 74 90 / 20 10 10 20 GIF 72 91 72 89 / 10 0 0 20 SRQ 74 89 74 89 / 10 0 0 20 BKV 69 91 69 90 / 10 0 10 30 SPG 77 90 76 89 / 10 0 10 20 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...NONE. && $$ UPDATE/AVIATION/MARINE...14/MROCZKA
AREA FORECAST DISCUSSION
NWS MIAMI FL
324 PM EDT SAT SEP 19 2015 .DISCUSSION... A RARE, QUIET RADAR FOR A SUMMER AFTERNOON HERE IN SOUTH FL. THE MORNING MIAMI SOUNDING SHOWS A CAP AT AROUND H85...AND CONVECTION SURE IS STRUGGLING TO GET GOING. A MAJOR FACTOR IS LACK OF CONVERGENCE WITH A WEST-NORTHWEST WIND NEAR 10 MPH EVERYWHERE AND NO ATLANTIC SEA BREEZE FORMING. HRRR SHOWS AN ATLANTIC SEA BREEZE DEVELOPING BY 5 PM...BUT THAT IS QUESTIONABLE. GOES SOUNDER PW FIELDS SHOW DRIER AIR OVER THE GULF MOVING IN AS WELL. GIVEN ALL OF THESE FACTORS...HAVE KEPT POPS ON THE LOW SIDE THROUGH THE REMAINDER OF THE DAY-EVENING. DRIER AIR WILL CONTINUE TO MOVE INTO THE AREA SUNDAY THROUGH MONDAY WITH A MEAN WIND FLOW OUT OF THE W-NW WHILE SURFACE WINDS OUT OF THE W-NW EVENTUALLY BECOME NORTHEAST-EAST AS SURFACE HIGH MOVES IN FROM THE NORTH. ISOLATED-SCATTERED MAINLY AFTERNOON/EVENING TSTORMS ARE FORECAST WITH FOCUS OVER THE INTERIOR AND EAST COAST ON SUNDAY AND SOUTHERN INTERIOR SECTIONS ON MONDAY. BY MID NEXT WEEK A MID LEVEL LOW IS STILL SHOWN BY THE GLOBAL MODELS TO DEVELOP AND CUT OFF THEN RETROGRADE OVER THE SOUTHEAST U.S. LATE IN THE WEEK...BUT THE PLACEMENT OF THIS CUT OFF LOW HAS BEEN CHANGING AND THIS HAS IMPLICATIONS ON JUST HOW WET AND STORMY IT GETS HERE MID-LATE NEXT WEEK. POPS WILL CONTINUE TO SHOW AN INCREASING TREND DURING THIS PERIOD AS EVEN THE LESS AGGRESSIVE MODEL RUNS STILL SHOW MORE STORMINESS AND INCREASING MOISTURE FROM THE SOUTH. /GREGORIA && .MARINE... NO CONCERNS AS WINDS LIGHTEN AND SEAS REMAIN GENERALLY LESS THAN 4 FT. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 76 90 76 89 / 30 30 30 20 FORT LAUDERDALE 77 90 78 89 / 30 40 40 30 MIAMI 77 92 78 90 / 20 50 30 40 NAPLES 77 90 76 91 / 20 20 10 20 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS MIAMI FL
145 PM EDT SAT SEP 19 2015 .AVIATION... DRIER AIR IS MOVING INTO THE AREA. THIS HAS SEVERELY LIMITED CONVECTIVE DEVELOPMENT TODAY. THERE STILL MAY BE SOME ISOLATED ACTIVITY LATE THIS AFTERNOON AND THIS EVENING, BUT EXPECT IT TO BE ISOLATED AT BEST. IT MAY NOT DEVELOP AT ALL. GIVEN THIS, REMOVED ANY MENTION OF CONVECTION. SO, VFR EXPECTED THROUGH THE TAF PERIOD. && .PREV DISCUSSION... /ISSUED 1123 AM EDT SAT SEP 19 2015/ UPDATE... UPDATED POPS ONCE AGAIN, LEAVING ONLY THE COASTAL AREAS UNDER A CHANCE, WITH THE OTHER AREAS DROPPED TO A SLIGHT CHANCE. THIS IS SUPPORTED BY BOTH THE LACK OF ACTIVITY OVER THE INTERIOR, THE FAIRLY CLEAR SKIES FOR THE LATE MORNING, AND THE HRRR, WHICH ONLY DEVELOPS A SHOWERS AND THUNDERSTORMS LATER THIS AFTERNOON INTO THE EVENING HOURS. PREV DISCUSSION... /ISSUED 1037 AM EDT SAT SEP 19 2015/ UPDATE... MUCH DIFFERENT MORNING THAN YESTERDAY MORNING. VERY LITTLE ACTIVITY ON RADAR. WITH ALL THE ACTIVITY OVER THE COASTAL WATERS AT THIS TIME. THE HRRR KEEPS THE WEATHER FAIRLY QUIET ACROSS THE CWA THROUGH THE AFTERNOON HOURS, WITH SOME ISOLATED TO SCATTERED CONVECTION THIS AFTERNOON. ONLY REAL CHANGES ARE TO SKY COVER AND TO ADJUST WIND TO INCLUDE MORE CURRENT MODEL RUNS, ALSO REDUCE POPS IN THE WESTERN PORTION OF THE CWA, GIVEN THE CURRENT RUN OF THE HRRR. OTHERWISE, THE FORECAST IS PROGRESSING FAIRLY WELL. PREV DISCUSSION... /ISSUED 340 AM EDT SAT SEP 19 2015/ DISCUSSION... TODAY-TONIGHT...SURFACE LOW CONTINUES TO SLOWLY DEEPEN OFF THE FL/GA COAST THIS MORNING WHILE RADAR AND SATELLITE SHOW THE WEAKER GULF LOW HAS BEEN ABSORBED INTO THE LARGER CIRCULATION. THE MID- UPPER LEVEL TROUGH THAT`S BEEN OVER THE STATE WILL ALSO BEGIN LIFTING OUT TO THE NORTHEAST...THOUGH THE AXIS WILL GET SHIFTED FURTHER SOUTH INTO S FLORIDA AS A RESULTING BRINGING COOLER MID LEVEL TEMPS. WAVER VAPOR SATELLITE IS SHOWING THE DEEPER MOISTURE BEING LIFTED OUT WITH SOME MID LEVEL DRYING ACROSS NORTH AND CENTRAL FLORIDA THAT MODELS BRING INTO SOUTH FLORIDA INTO THE AFTERNOON. STEERING FLOW HAS PICKED UP OUT OF THE SW WITH THE CURRENT SHOWERS AND STORMS OVER THE WATERS THIS MORNING MOVING AT AROUND 20KTS. LITTLE CHANGE IN THIS SPEED THROUGH THE DAY SO WE WILL SEE FAIRLY QUICK MOVING SHOWERS AND STORMS INTO THE AFTERNOON. ACTIVITY WILL ONCE AGAIN FAVOR EAST COAST...WITH MODELS FOCUSING MORE TOWARDS BROWARD /MIAMI-DADE WHERE TRAILING SURFACE TROUGH LIES. GIVEN STORM MOTION...DON`T EXPECT HEAVY RAIN TO BE AS SIGNIFICANT A CONCERN BUT WILL HAVE TO WATCH FOR SOME TRAINING IN SPOTS GIVEN THE ALREADY SATURATED GROUND. OVERALL COVERAGE IS ALSO EXPECTED TO BE LOWER THAN THE PAST FEW DAYS. ACTIVITY SHOULD BE FAIRLY QUICK TO PUSH OFFSHORE THIS EVENING WITH ACTIVITY JUST OVER THE WATERS OVERNIGHT. SUNDAY...MID-UPPER LEVEL TROUGH CONTINUES TO WEAKEN AND LIFT OFF TO THE NORTHEAST INTO SUNDAY...TAKING WITH IT THE DEEPENING SURFACE LOW OFFSHORE THE CAROLINA COAST. TRAILING EDGE OF THE TROUGH LINGERS OVER S FLORIDA WITH CONTINUING DEEP AND BRISK WEST-SOUTHWESTERLY FLOW. DRIER AIR BEGINS TO WORK FURTHER DOWN THE PENINSULA IN THE CYCLONIC FLOW AROUND THE BACK SIDE OF THE DISTANT LOW...PUSHING THE DEEPER TROPICAL MOISTURE SOUTH OF THE STATE. RAIN CHANCES ACROSS THE REGION DIMINISH CONSIDERABLY...STILL FAVORING THE EAST COAST AND FAR SOUTH PENINSULA IN FAST MOVING SHOWERS AND A FEW STORMS. LONG TERM (MONDAY-FRIDAY)...SURFACE LOW CONTINUES TO LIFT FURTHER OFF TO THE NORTHEAST EARLY NEXT WEEK LEAVING A WEAK PRESSURE GRADIENT IN PLACE ACROSS THE STATE WITH DAILY SEA BREEZES BECOMING THE MAIN DRIVER OF AFTERNOON CONVECTION. MODELS REMAIN CONSISTENT IN SHOWING FAIRLY DECENT MID LEVEL DRY AIR WRAPPING AROUND THE BACK OF THE LOW INTO THE STATE MON-WED WHICH LOOKS TO KEEP RAIN CHANCES A LITTLE BELOW NORMAL AT 20-30 PERCENT...INCREASING TO 30-40 PERCENT ON WED WITH SOME MOISTURE ADVECTION AHEAD OF THE NEXT TROUGH. WEST- SOUTHWESTERLY STEERING COMPONENT REMAINS IN PLACE ON MONDAY...KEEPING THE BEST (THOUGH MUCH LOWER) RAIN CHANCES TOWARDS THE EAST COAST...BEFORE BECOMING LIGHT AND VARIABLE INTO MID WEEK WITH MORE ACTIVITY OVER THE INTERIOR. MID TO LATE WEEK MODELS SHOW THE NEXT TROUGH MOVING INTO THE EASTERN US CUTTING OFF OVER THE SOUTHEAST...A LITTLE FARTHER NORTH THAN YESTERDAY`S RUNS. 19/00Z GFS LIFTS THE LOW OUT INTO THE MID-ATLANTIC FAIRLY QUICKLY WHILE THE ECMWF STILL HAS IT RETROGRADING BACK TO THE GULF. WITH THE GFS`S MORE PROGRESSIVE SOLUTION...FLOW REMAINS MORE SOUTHWEST THAN SOUTH AND DEEP MOISTURE ADVECTION IS NOT QUITE AS PRONOUNCED ACROSS S FL. NONETHELESS...WE ARE LOOKING AT A RETURN TO A STORMY PATTERN TOWARDS THE END OF NEXT WEEK. MARINE...MODERATE SW WINDS OVER THE ATLANTIC TODAY 10-15KTS AS SURFACE LOW OFF THE GA/FL COAST DEEPENS AND SLOWLY MOVES OFF TO THE NE. WEST-NW WINDS 10KTS OVER THE GULF WATERS. PRESSURE GRADIENT COLLAPSES ON SUN RESULTING IN LIGHT WEST-NW WINDS 5-10KTS...VEERING N-NE MON AND TUES THEN EAST ON WED. SEAS GENERALLY 2FT OR LESS...WITH UP TO 3FT IN THE GULF STREAM THIS AFTERNOON AND 4FT TUES- THURS WITH SOME INCOMING SWELL AND NORTH FETCH. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 75 91 77 88 / 20 30 20 20 FORT LAUDERDALE 77 90 78 88 / 20 40 30 30 MIAMI 77 91 78 90 / 20 40 30 40 NAPLES 76 90 75 92 / 10 20 10 20 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...13/SI LONG TERM....88/ALM AVIATION...13/SI
AREA FORECAST DISCUSSION
NWS MIAMI FL
1123 AM EDT SAT SEP 19 2015 .UPDATE... UPDATED POPS ONCE AGAIN, LEAVING ONLY THE COASTAL AREAS UNDER A CHANCE, WITH THE OTHER AREAS DROPPED TO A SLIGHT CHANCE. THIS IS SUPPORTED BY BOTH THE LACK OF ACTIVITY OVER THE INTERIOR, THE FAIRLY CLEAR SKIES FOR THE LATE MORNING, AND THE HRRR, WHICH ONLY DEVELOPS A SHOWERS AND THUNDERSTORMS LATER THIS AFTERNOON INTO THE EVENING HOURS. && .PREV DISCUSSION... /ISSUED 1037 AM EDT SAT SEP 19 2015/ UPDATE... MUCH DIFFERENT MORNING THAN YESTERDAY MORNING. VERY LITTLE ACTIVITY ON RADAR. WITH ALL THE ACTIVITY OVER THE COASTAL WATERS AT THIS TIME. THE HRRR KEEPS THE WEATHER FAIRLY QUIET ACROSS THE CWA THROUGH THE AFTERNOON HOURS, WITH SOME ISOLATED TO SCATTERED CONVECTION THIS AFTERNOON. ONLY REAL CHANGES ARE TO SKY COVER AND TO ADJUST WIND TO INCLUDE MORE CURRENT MODEL RUNS, ALSO REDUCE POPS IN THE WESTERN PORTION OF THE CWA, GIVEN THE CURRENT RUN OF THE HRRR. OTHERWISE, THE FORECAST IS PROGRESSING FAIRLY WELL. PREV DISCUSSION... /ISSUED 808 AM EDT SAT SEP 19 2015/ AVIATION... MAINLY VFR CONDITIONS ACROSS SOUTH FLORIDA TODAY. THERE IS A CHANCE OF SHOWERS AND THUNDERSTORMS ALONG THE EAST COAST OF SOUTH FLORIDA, MAINLY THIS AFTERNOON. HOWEVER, THE COVERAGE SHOULD BE LESS THAN YESTERDAY. GIVEN THIS, ONLY VCTS IN THE TAFS TODAY. EXPECT WIND TO CONTINUE FROM THE SOUTHWEST THROUGH THE DAY, GOING LIGHT AND VARIABLE THIS EVENING. PREV DISCUSSION... /ISSUED 340 AM EDT SAT SEP 19 2015/ DISCUSSION... TODAY-TONIGHT...SURFACE LOW CONTINUES TO SLOWLY DEEPEN OFF THE FL/GA COAST THIS MORNING WHILE RADAR AND SATELLITE SHOW THE WEAKER GULF LOW HAS BEEN ABSORBED INTO THE LARGER CIRCULATION. THE MID- UPPER LEVEL TROUGH THAT`S BEEN OVER THE STATE WILL ALSO BEGIN LIFTING OUT TO THE NORTHEAST...THOUGH THE AXIS WILL GET SHIFTED FURTHER SOUTH INTO S FLORIDA AS A RESULTING BRINGING COOLER MID LEVEL TEMPS. WAVER VAPOR SATELLITE IS SHOWING THE DEEPER MOISTURE BEING LIFTED OUT WITH SOME MID LEVEL DRYING ACROSS NORTH AND CENTRAL FLORIDA THAT MODELS BRING INTO SOUTH FLORIDA INTO THE AFTERNOON. STEERING FLOW HAS PICKED UP OUT OF THE SW WITH THE CURRENT SHOWERS AND STORMS OVER THE WATERS THIS MORNING MOVING AT AROUND 20KTS. LITTLE CHANGE IN THIS SPEED THROUGH THE DAY SO WE WILL SEE FAIRLY QUICK MOVING SHOWERS AND STORMS INTO THE AFTERNOON. ACTIVITY WILL ONCE AGAIN FAVOR EAST COAST...WITH MODELS FOCUSING MORE TOWARDS BROWARD /MIAMI-DADE WHERE TRAILING SURFACE TROUGH LIES. GIVEN STORM MOTION...DON`T EXPECT HEAVY RAIN TO BE AS SIGNIFICANT A CONCERN BUT WILL HAVE TO WATCH FOR SOME TRAINING IN SPOTS GIVEN THE ALREADY SATURATED GROUND. OVERALL COVERAGE IS ALSO EXPECTED TO BE LOWER THAN THE PAST FEW DAYS. ACTIVITY SHOULD BE FAIRLY QUICK TO PUSH OFFSHORE THIS EVENING WITH ACTIVITY JUST OVER THE WATERS OVERNIGHT. SUNDAY...MID-UPPER LEVEL TROUGH CONTINUES TO WEAKEN AND LIFT OFF TO THE NORTHEAST INTO SUNDAY...TAKING WITH IT THE DEEPENING SURFACE LOW OFFSHORE THE CAROLINA COAST. TRAILING EDGE OF THE TROUGH LINGERS OVER S FLORIDA WITH CONTINUING DEEP AND BRISK WEST-SOUTHWESTERLY FLOW. DRIER AIR BEGINS TO WORK FURTHER DOWN THE PENINSULA IN THE CYCLONIC FLOW AROUND THE BACK SIDE OF THE DISTANT LOW...PUSHING THE DEEPER TROPICAL MOISTURE SOUTH OF THE STATE. RAIN CHANCES ACROSS THE REGION DIMINISH CONSIDERABLY...STILL FAVORING THE EAST COAST AND FAR SOUTH PENINSULA IN FAST MOVING SHOWERS AND A FEW STORMS. LONG TERM (MONDAY-FRIDAY)...SURFACE LOW CONTINUES TO LIFT FURTHER OFF TO THE NORTHEAST EARLY NEXT WEEK LEAVING A WEAK PRESSURE GRADIENT IN PLACE ACROSS THE STATE WITH DAILY SEA BREEZES BECOMING THE MAIN DRIVER OF AFTERNOON CONVECTION. MODELS REMAIN CONSISTENT IN SHOWING FAIRLY DECENT MID LEVEL DRY AIR WRAPPING AROUND THE BACK OF THE LOW INTO THE STATE MON-WED WHICH LOOKS TO KEEP RAIN CHANCES A LITTLE BELOW NORMAL AT 20-30 PERCENT...INCREASING TO 30-40 PERCENT ON WED WITH SOME MOISTURE ADVECTION AHEAD OF THE NEXT TROUGH. WEST- SOUTHWESTERLY STEERING COMPONENT REMAINS IN PLACE ON MONDAY...KEEPING THE BEST (THOUGH MUCH LOWER) RAIN CHANCES TOWARDS THE EAST COAST...BEFORE BECOMING LIGHT AND VARIABLE INTO MID WEEK WITH MORE ACTIVITY OVER THE INTERIOR. MID TO LATE WEEK MODELS SHOW THE NEXT TROUGH MOVING INTO THE EASTERN US CUTTING OFF OVER THE SOUTHEAST...A LITTLE FARTHER NORTH THAN YESTERDAY`S RUNS. 19/00Z GFS LIFTS THE LOW OUT INTO THE MID-ATLANTIC FAIRLY QUICKLY WHILE THE ECMWF STILL HAS IT RETROGRADING BACK TO THE GULF. WITH THE GFS`S MORE PROGRESSIVE SOLUTION...FLOW REMAINS MORE SOUTHWEST THAN SOUTH AND DEEP MOISTURE ADVECTION IS NOT QUITE AS PRONOUNCED ACROSS S FL. NONETHELESS...WE ARE LOOKING AT A RETURN TO A STORMY PATTERN TOWARDS THE END OF NEXT WEEK. MARINE...MODERATE SW WINDS OVER THE ATLANTIC TODAY 10-15KTS AS SURFACE LOW OFF THE GA/FL COAST DEEPENS AND SLOWLY MOVES OFF TO THE NE. WEST-NW WINDS 10KTS OVER THE GULF WATERS. PRESSURE GRADIENT COLLAPSES ON SUN RESULTING IN LIGHT WEST-NW WINDS 5-10KTS...VEERING N-NE MON AND TUES THEN EAST ON WED. SEAS GENERALLY 2FT OR LESS...WITH UP TO 3FT IN THE GULF STREAM THIS AFTERNOON AND 4FT TUES- THURS WITH SOME INCOMING SWELL AND NORTH FETCH. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 90 75 91 77 / 30 20 30 20 FORT LAUDERDALE 91 77 90 78 / 30 20 40 30 MIAMI 91 77 91 78 / 30 20 40 30 NAPLES 89 76 90 75 / 20 10 20 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...13/SI LONG TERM....88/ALM
AREA FORECAST DISCUSSION
NWS MIAMI FL
1037 AM EDT SAT SEP 19 2015 .UPDATE... MUCH DIFFERENT MORNING THAN YESTERDAY MORNING. VERY LITTLE ACTIVITY ON RADAR. WITH ALL THE ACTIVITY OVER THE COASTAL WATERS AT THIS TIME. THE HRRR KEEPS THE WEATHER FAIRLY QUIET ACROSS THE CWA THROUGH THE AFTERNOON HOURS, WITH SOME ISOLATED TO SCATTERED CONVECTION THIS AFTERNOON. ONLY REAL CHANGES ARE TO SKY COVER AND TO ADJUST WIND TO INCLUDE MORE CURRENT MODEL RUNS, ALSO REDUCE POPS IN THE WESTERN PORTION OF THE CWA, GIVEN THE HRRRS CURRENT RUN. OTHERWISE, THE FORECAST IS PROGRESSING FAIRLY WELL. && .PREV DISCUSSION... /ISSUED 808 AM EDT SAT SEP 19 2015/ AVIATION... MAINLY VFR CONDITIONS ACROSS SOUTH FLORIDA TODAY. THERE IS A CHANCE OF SHOWERS AND THUNDERSTORMS ALONG THE EAST COAST OF SOUTH FLORIDA, MAINLY THIS AFTERNOON. HOWEVER, THE COVERAGE SHOULD BE LESS THAN YESTERDAY. GIVEN THIS, ONLY VCTS IN THE TAFS TODAY. EXPECT WIND TO CONTINUE FROM THE SOUTHWEST THROUGH THE DAY, GOING LIGHT AND VARIABLE THIS EVENING. PREV DISCUSSION... /ISSUED 340 AM EDT SAT SEP 19 2015/ DISCUSSION... TODAY-TONIGHT...SURFACE LOW CONTINUES TO SLOWLY DEEPEN OFF THE FL/GA COAST THIS MORNING WHILE RADAR AND SATELLITE SHOW THE WEAKER GULF LOW HAS BEEN ABSORBED INTO THE LARGER CIRCULATION. THE MID- UPPER LEVEL TROUGH THAT`S BEEN OVER THE STATE WILL ALSO BEGIN LIFTING OUT TO THE NORTHEAST...THOUGH THE AXIS WILL GET SHIFTED FURTHER SOUTH INTO S FLORIDA AS A RESULTING BRINGING COOLER MID LEVEL TEMPS. WAVER VAPOR SATELLITE IS SHOWING THE DEEPER MOISTURE BEING LIFTED OUT WITH SOME MID LEVEL DRYING ACROSS NORTH AND CENTRAL FLORIDA THAT MODELS BRING INTO SOUTH FLORIDA INTO THE AFTERNOON. STEERING FLOW HAS PICKED UP OUT OF THE SW WITH THE CURRENT SHOWERS AND STORMS OVER THE WATERS THIS MORNING MOVING AT AROUND 20KTS. LITTLE CHANGE IN THIS SPEED THROUGH THE DAY SO WE WILL SEE FAIRLY QUICK MOVING SHOWERS AND STORMS INTO THE AFTERNOON. ACTIVITY WILL ONCE AGAIN FAVOR EAST COAST...WITH MODELS FOCUSING MORE TOWARDS BROWARD /MIAMI-DADE WHERE TRAILING SURFACE TROUGH LIES. GIVEN STORM MOTION...DON`T EXPECT HEAVY RAIN TO BE AS SIGNIFICANT A CONCERN BUT WILL HAVE TO WATCH FOR SOME TRAINING IN SPOTS GIVEN THE ALREADY SATURATED GROUND. OVERALL COVERAGE IS ALSO EXPECTED TO BE LOWER THAN THE PAST FEW DAYS. ACTIVITY SHOULD BE FAIRLY QUICK TO PUSH OFFSHORE THIS EVENING WITH ACTIVITY JUST OVER THE WATERS OVERNIGHT. SUNDAY...MID-UPPER LEVEL TROUGH CONTINUES TO WEAKEN AND LIFT OFF TO THE NORTHEAST INTO SUNDAY...TAKING WITH IT THE DEEPENING SURFACE LOW OFFSHORE THE CAROLINA COAST. TRAILING EDGE OF THE TROUGH LINGERS OVER S FLORIDA WITH CONTINUING DEEP AND BRISK WEST-SOUTHWESTERLY FLOW. DRIER AIR BEGINS TO WORK FURTHER DOWN THE PENINSULA IN THE CYCLONIC FLOW AROUND THE BACK SIDE OF THE DISTANT LOW...PUSHING THE DEEPER TROPICAL MOISTURE SOUTH OF THE STATE. RAIN CHANCES ACROSS THE REGION DIMINISH CONSIDERABLY...STILL FAVORING THE EAST COAST AND FAR SOUTH PENINSULA IN FAST MOVING SHOWERS AND A FEW STORMS. LONG TERM (MONDAY-FRIDAY)...SURFACE LOW CONTINUES TO LIFT FURTHER OFF TO THE NORTHEAST EARLY NEXT WEEK LEAVING A WEAK PRESSURE GRADIENT IN PLACE ACROSS THE STATE WITH DAILY SEA BREEZES BECOMING THE MAIN DRIVER OF AFTERNOON CONVECTION. MODELS REMAIN CONSISTENT IN SHOWING FAIRLY DECENT MID LEVEL DRY AIR WRAPPING AROUND THE BACK OF THE LOW INTO THE STATE MON-WED WHICH LOOKS TO KEEP RAIN CHANCES A LITTLE BELOW NORMAL AT 20-30 PERCENT...INCREASING TO 30-40 PERCENT ON WED WITH SOME MOISTURE ADVECTION AHEAD OF THE NEXT TROUGH. WEST- SOUTHWESTERLY STEERING COMPONENT REMAINS IN PLACE ON MONDAY...KEEPING THE BEST (THOUGH MUCH LOWER) RAIN CHANCES TOWARDS THE EAST COAST...BEFORE BECOMING LIGHT AND VARIABLE INTO MID WEEK WITH MORE ACTIVITY OVER THE INTERIOR. MID TO LATE WEEK MODELS SHOW THE NEXT TROUGH MOVING INTO THE EASTERN US CUTTING OFF OVER THE SOUTHEAST...A LITTLE FARTHER NORTH THAN YESTERDAY`S RUNS. 19/00Z GFS LIFTS THE LOW OUT INTO THE MID-ATLANTIC FAIRLY QUICKLY WHILE THE ECMWF STILL HAS IT RETROGRADING BACK TO THE GULF. WITH THE GFS`S MORE PROGRESSIVE SOLUTION...FLOW REMAINS MORE SOUTHWEST THAN SOUTH AND DEEP MOISTURE ADVECTION IS NOT QUITE AS PRONOUNCED ACROSS S FL. NONETHELESS...WE ARE LOOKING AT A RETURN TO A STORMY PATTERN TOWARDS THE END OF NEXT WEEK. MARINE...MODERATE SW WINDS OVER THE ATLANTIC TODAY 10-15KTS AS SURFACE LOW OFF THE GA/FL COAST DEEPENS AND SLOWLY MOVES OFF TO THE NE. WEST-NW WINDS 10KTS OVER THE GULF WATERS. PRESSURE GRADIENT COLLAPSES ON SUN RESULTING IN LIGHT WEST-NW WINDS 5-10KTS...VEERING N-NE MON AND TUES THEN EAST ON WED. SEAS GENERALLY 2FT OR LESS...WITH UP TO 3FT IN THE GULF STREAM THIS AFTERNOON AND 4FT TUES- THURS WITH SOME INCOMING SWELL AND NORTH FETCH. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 90 75 91 77 / 30 20 30 20 FORT LAUDERDALE 91 77 90 78 / 40 20 40 30 MIAMI 91 77 91 78 / 30 20 40 30 NAPLES 89 76 90 75 / 20 10 20 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...13/SI LONG TERM....88/ALM
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1019 AM EDT SAT SEP 19 2015 .DISCUSSION...LOW CLOUDS WHICH IMPACTED NORTHERN COUNTIES NOW BEGINNING TO LIFT...TRANSITIONING TO PARTLY/MOSTLY SUNNY LATE MRONING. UPPER TROUGH REMAINS OVER REGION TODAY...WITH SURFACE TROUGH EXTENDING FROM SURFACE LOW WELL OFFSHORE JACKSONVILLE TO THE TREASURE COAST/LAKE OKEECHOBEE AREA. CYCLONIC FLOW PATTERN WILL AFFECT CWA TODAY TO THE SW OF SURFACE LOW. HRRR AND LOCAL WRF BOTH SUGGEST ONSHORE FLOW WILL INITIATE AREA OF SCATTERED SHOWERS OVER/NEAR VOLUSIA COUNTY...WITH ACTIVITY EXPANDING INTO PRIMARILY SEMINOLE/ORANGE AND NORTHERN BREVARD COUNTIES DURING THE AFTERNOON...WITH ISOLATED STORMS POSSIBLE. EXPECT CONVERGENCE/LIFT ALONG BOUNDARY OVER SOUTHERN COUNTIES TO ALSO PROMPT SOME CONVECTIVE DEVELOPMENT. CURRENT POP DISTRIBUTION AGREES WELL WITH SCENARIO OF HIGHEST POPS (40) NE AND A LITTLE LOWER SOUTH AND INLAND. EXPECT ISOLATED SHOWERS/STORMS TO LINGER INTO EARLY EVENING. MAX TEMPS UPPER 80S COAST AND AROUND 90 INLAND. && .AVIATION...LIFR CIGS AT NORTH/INTERIOR TAF SITES WILL LIFT/DIMINISH BY 15Z. SHOWER/STORM COVERAGE LOW ENOUGH TO OMIT FROM TAFS...BUT BASED ON TRENDS...MAY NEED TO ADD SMALL WINDOW OF SHRA AND MVFR CIGS TO SOME TAF SITES...MAINLY KDAB/KTIX/KSFB. && .MARINE...N WINDS INCREASING TO 15-20 KT OFFSHORE/NORTH THIS AFTERNOON AND 10-15 KT ELSEWHERE...EXCEPT 5-10 KT NEARSHORE/SOUTH. SEAS 3-5 FT...EXCEPT BUILDING TO 4-6 FT OFFSHORE/NORTH THIS AFTERNOON. NO CHANGES TO EARLY MORNING CWF. && .HYDROLOGY... AS A RESULT OF THE RECENT HEAVY RAINS...THE ST. JOHNS RIVER ABOVE LAKE HARNEY /GENF1/ HAS REACHED 6.1FT...WHICH IS 0.4 FEET BELOW ACTION STAGE (6.5FT). THE RIVER IS FORECAST TO REACH THE LOWER THRESHOLD OF ACTION STAGE EARLY SUNDAY...AND REMAIN NEARLY STEADY STATE WELL INTO NEXT WEEK. THE SAINT JOHNS RIVER AT ASTOR /ASTF1/ HAS REACHED 2.25FT...WHICH IS 0.25 FEET BELOW ACTIONS STAGE (2.5FT). THE RIVER WILL REMAIN NEAR ACTION STAGE OVER THE NEXT SEVERAL DAYS DUE TO SLIGHT RISES DOWNSTREAM AND NORTHERLY WINDS SLOWING DRAINAGE UPSTREAM. && .PRELIMINARY POINT TEMPS/POPS... DAB 87 73 89 71 / 40 20 10 10 MCO 89 73 91 72 / 40 20 20 10 MLB 89 73 90 74 / 30 20 20 10 VRB 89 72 88 70 / 30 20 20 10 LEE 88 73 92 73 / 30 20 10 10 SFB 88 73 91 72 / 40 20 10 10 ORL 89 74 92 74 / 40 20 20 10 FPR 90 73 89 70 / 30 20 20 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ SHORT TERM...SPRATT IMPACT WEATHER/DSS...GLITTO
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1039 PM EDT SUN SEP 20 2015 .SYNOPSIS... AN APPROACHING COLD FRONT WILL REACH THE NORTH PART OF THE FORECAST AREA LATE TONIGHT. THE FRONT WILL SLOWLY SINK SOUTHWARD AND THROUGH THE AREA MONDAY AND MONDAY NIGHT. THE FRONT WILL BE JUST SOUTH OF THE REGION TUESDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... GENERALLY ZONAL UPPER FLOW IN PROGRESS ACROSS THE SOUTHERN TIER OF STATES EAST OF THE ROCKIES. A WEAK SLOW MOVING UPPER TROUGH REMAINS OFFSHORE. AN UPPER IMPULSE CURRENTLY MOVING ACROSS THE LOWER MS VALLEY. CURRENT SURFACE ANALYSIS INDICATES A FRONT NEAR THE NC/SC BORDER STRETCHING INTO NORTHERN GA. LATEST COMPOSITE RADAR SHOWING SCATTERED SHOWERS TO OUR N AND NW MAINLY ACROSS THE NC MOUNTAINS. LATEST SPC HRRR SHOWING SOME WEAK CONVECTION DEVELOPING OVER PORTIONS OF THE PEE DEE AND EASTERN MIDLANDS LATER TONIGHT SO WILL INCLUDE A SLIGHT CHANCE POP IN THOSE LOCATIONS. MAINLY LIGHT WINDS EXPECTED TONIGHT WITH OVERNIGHT LOWS IN THE MID 60S. && .SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY/... THE COLD FRONT SLOWLY MOVING SOUTHWARD SHOULD BE IN THE FORECAST AREA MONDAY INTO MONDAY NIGHT...AND JUST SOUTH OF THE AREA TUESDAY. THE MODELS SHOW UPPER TROUGHING AND ASSOCIATED INSTABILITY SUPPORTING A CHANCE OF SHOWERS AND THUNDERSTORMS. THE GFS AND NAM DISPLAY THE DEEPEST MOISTURE LATE MONDAY AFTERNOON AND EVENING. THE GFS AND NAM MOS PLUS SREF GUIDANCE SUGGEST THE HIGHEST SHOWER CHANCE LATE MONDAY AFTERNOON AND EVENING. INSTABILITY AIDED BY THE UPPER TROUGH INDICATES POSSIBLE THUNDERSTORMS THROUGH THE PERIOD...BUT THE GREATEST CHANCE SHOULD BE MONDAY AFTERNOON AND EVENING AND IN THE SOUTH PART OF THE FORECAST AREA BECAUSE OF THE LINGERING EFFECTS OF HEATING JUST AHEAD OF THE FRONT. LEANED TOWARD THE HIGHER GUIDANCE TEMPERATURES IN THE SOUTH PART JUST AHEAD OF THE FRONT MONDAY...AND THE COOLER TEMPERATURES TUESDAY BECAUSE OF CLOUDINESS IN A WEDGE-LIKE PATTERN. OTHERWISE...FOLLOWED THE GUIDANCE CONSENSUS TEMPERATURES. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... CONFIDENCE IS LOW DURING THE MEDIUM-RANGE PERIOD. THE ECMWF AND GFS GENERALLY DISPLAYED A FRONT NEAR THE SOUTHEAST COAST WITH A LONG-FETCH ONSHORE FLOW. THE MODELS DIFFERED WITH THE AMOUNT OF MOISTURE WRAPPING INTO THE FORECAST AREA WITH THE ECMWF TENDING TO SHOW MORE MOISTURE COMPARED TO THE GFS. THE GFS ENSEMBLE GUIDANCE INDICATED A HIGH SPREAD. WE CONTINUED THE FORECAST OF CHANCE POPS WHICH WAS SUPPORTED BY AN AVERAGE OF THE GFS...ECMWF...AND EKD MOS POPS. THE MOS WAS CONSISTENT WITH TEMPERATURES NEAR CLIMATOLOGY. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... VFR EXPECTED ALTHOUGH THREAT OF MVFR FOG AT AGS/OGB TOWARD DAYBREAK. GENERALLY LIGHT WINDS EXPECTED INTO TONIGHT...LEADING TO POSSIBLE FOG CONCERNS AT FOG PRONE AGS AND OGB. HOWEVER...PREMISE FOR SOME INCREASING MID AND HIGH LEVEL CLOUD COVER FROM THE WEST REDUCES CONFIDENCE. A FRONTAL BOUNDARY WILL AFFECT THE REGION MONDAY...AND PROVIDE A CHANCE OF SHOWERS...WITH A POSSIBLE THUNDERSTORM IN THE AFTERNOON. SCATTERED TO BROKEN CUMULUS EXPECTED THROUGH THE AFTERNOON. EXTENDED AVIATION OUTLOOK... MVFR CIG RESTRICTIONS POSSIBLE LATE MONDAY THROUGH EARLY TUESDAY...WITH MVFR VSBY RESTRICTIONS POSSIBLE IN SHOWER ACTIVITY THROUGH TUESDAY. NO SIGNIFICANT IMPACTS TO AVIATION EXPECTED WEDNESDAY. LOW CONFIDENCE LATE IN THE FORECAST PERIOD. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
856 PM CDT SUN SEP 20 2015 .UPDATE... ISSUED AT 853 PM CDT SUN SEP 20 2015 Another quiet but cool night across central and southeast Illinois as high pressure remains in control of the local weather. Light winds, mostly clear skies, and a dry airmass should allow overnight temperatures to fall into the 40s again in many areas. Only plan minor tweaks to the hourly nighttime grids for the latest trends. && .SHORT TERM...(TONIGHT) ISSUED AT 244 PM CDT SUN SEP 20 2015 Broad expanse of high pressure set up in the Midwest with the ridge axis stretched from the eastern Great Lakes back into Missouri. A small shortwave on sat imagery to the northwest forecast in the HRRR to pass to the north this evening. Dominant high pressure should give Central Illinois another quiet night. Winds will become light and variable under the ridge, with temps dropping into the upper 40s and lower 50s. Not much to discuss in terms of weather, but will mention the potential for very patchy light fog/vis drops. However, leaving it out of the grids as the afternoon dewpoints are dropping several degrees as the llvls mix out in the day time heating. .LONG TERM...(Monday THROUGH Sunday) ISSUED AT 244 PM CDT SUN SEP 20 2015 Seeing a consistent signal in the 12z models for a dry week in the extended forecast across central and southeast IL. High pressure centered over the Great Lakes and extending southwest across Illinois will gradually shift to the east over the first half of this week. The southwest end of the surface ridge looks to remain across central and southern Illinois during that time, keeping seasonable and dry conditions across our forecast area. A cold front will approach NW Illinois on Tuesday, reaching eastern Iowa by 00z Wed/7pm Tues. The front is projected to stall out in that general area for the rest of the week, as a ridge remains entrenched across the eastern states due to the blocking effects of a low pressure system off the central East Coast. The end result will be some increase in cloud cover for our areas west of I-55 for the last half of the week, but plenty of dry air above and below the cloud layer will keep precip at bay. Low pressure progressing from the SW states will move northeast along the front later this week, reaching the Upper Mississippi River Valley Thursday into Friday. That will bring another period of increased cloud cover for our western counties, but no rain. That low is expected to dissipate on Friday as it passes by to the north of IL, with expanding high pressure across Illinois in it`s wake. That will keep dry conditions in the forecast through next weekend. As for temperatures this week, the chilly air will remain across our area into Tuesday. However, southerly flow will develop ahead of the approaching cold front, bring warmer air to our area the rest of the week. Highs will reach back into the lower 80s from Wednesday to Sunday. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z Monday EVENING) ISSUED AT 628 PM CDT SUN SEP 20 2015 High pressure will continue to dominate the weather across the central Illinois terminals through the 00Z TAF valid time. VFR conditions will prevail, with generally light winds and minimal cloud cover. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Bak SHORT TERM...HJS LONG TERM...Shimon AVIATION...Bak
AREA FORECAST DISCUSSION
NWS LINCOLN IL
629 PM CDT SUN SEP 20 2015 .SHORT TERM...(TONIGHT) ISSUED AT 244 PM CDT SUN SEP 20 2015 Broad expanse of high pressure set up in the Midwest with the ridge axis stretched from the eastern Great Lakes back into Missouri. A small shortwave on sat imagery to the northwest forecast in the HRRR to pass to the north this evening. Dominant high pressure should give Central Illinois another quiet night. Winds will become light and variable under the ridge, with temps dropping into the upper 40s and lower 50s. Not much to discuss in terms of weather, but will mention the potential for very patchy light fog/vis drops. However, leaving it out of the grids as the afternoon dewpoints are dropping several degrees as the llvls mix out in the day time heating. .LONG TERM...(Monday THROUGH Sunday) ISSUED AT 244 PM CDT SUN SEP 20 2015 Seeing a consistent signal in the 12z models for a dry week in the extended forecast across central and southeast IL. High pressure centered over the Great Lakes and extending southwest across Illinois will gradually shift to the east over the first half of this week. The southwest end of the surface ridge looks to remain across central and southern Illinois during that time, keeping seasonable and dry conditions across our forecast area. A cold front will approach NW Illinois on Tuesday, reaching eastern Iowa by 00z Wed/7pm Tues. The front is projected to stall out in that general area for the rest of the week, as a ridge remains entrenched across the eastern states due to the blocking effects of a low pressure system off the central East Coast. The end result will be some increase in cloud cover for our areas west of I-55 for the last half of the week, but plenty of dry air above and below the cloud layer will keep precip at bay. Low pressure progressing from the SW states will move northeast along the front later this week, reaching the Upper Mississippi River Valley Thursday into Friday. That will bring another period of increased cloud cover for our western counties, but no rain. That low is expected to dissipate on Friday as it passes by to the north of IL, with expanding high pressure across Illinois in it`s wake. That will keep dry conditions in the forecast through next weekend. As for temperatures this week, the chilly air will remain across our area into Tuesday. However, southerly flow will develop ahead of the approaching cold front, bring warmer air to our area the rest of the week. Highs will reach back into the lower 80s from Wednesday to Sunday. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z Monday EVENING) ISSUED AT 628 PM CDT SUN SEP 20 2015 High pressure will continue to dominate the weather across the central Illinois terminals through the 00Z TAF valid time. VFR conditions will prevail, with generally light winds and minimal cloud cover. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...HJS LONG TERM...Shimon AVIATION...Bak
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1253 AM CDT SAT SEP 19 2015 .SHORT TERM... 211 PM CDT THROUGH TONIGHT... IN ADDITION TO SOME LIGHT RAIN/DRIZZLE FARTHER NORTH...WE ARE BEGINNING TO SEE SCATTERED SHOWER DEVELOPMENT FARTHER NORTH INTO OUR AREA THIS AFTERNOON AS THE AREA BEGINS TO FEEL MORE OF THE LIFT FROM A PAIR OF LEADING SHORTWAVES AHEAD OF A VERY WELL DEFINED UPPER LEVEL TROUGH AND CLOSED CIRCULATION MOVING EAST THROUGH THE DAKOTAS. THE FIRST OF THESE WAVES IS PUSHING INTO WEST CENTRAL ILLINOIS WHERE MORE ORGANIZED THUNDERSTORM ACTIVITY IS FOCUSED. THESE ARE IN AREAS WHERE EARLIER BREAKS IN LOWER LEVEL STRATUS HAVE ENABLED GREATER DESTABILIZATION. A STATIONARY FRONTAL BOUNDARY REMAINS DRAPED ACROSS THE WESTERN CWA. ADDITIONAL ELEVATED THUNDERSTORMS THROUGH SOUTHERN IOWA AND EXTENDING TO NEAR THE MISSISSIPPI RIVER IN FAR EASTERN IOWA AHEAD OF THESE ADDITIONAL LEADING SHORTWAVES. EXPECT SHOWERS AND ISOLATED THUNDERSTORMS TO INCREASE IN COVERAGE INTO NORTHEAST ILLINOIS AND NORTHWEST INDIANA. AS THE AFTERNOON CONTINUES. WITH THE THICK CLOUD COVER FARTHER NORTH...FEEL THE MORE ACTIVE STORMS WILL BE CONFINED ALONG AND SOUTH OF INTERSTATE 80 WHERE LOCALLY HEAVY RAINFALL IS EXPECTED AND STORM MOTION IS NOT SUPER FAST. A SEVERE THREAT EXISTS AS WELL DUE TO MODEST MID LEVEL LAPSE RATES (NEAR 7 DEG/KM ON THE KDVN MORNING SOUNDING)...THOUGH SHEAR HAS DECREASED SOMEWHAT LOWER THAN WHAT WAS DEPICTED EARLIER TODAY ON THE RAP SPC MESOANALYSIS. IT IS FORECAST TO INCREASE AGAIN AS THE AFTERNOON CONTINUES...KEEPING SOME THREAT FOR GUSTY WINDS AND HAIL MAINLY FOR OUR WESTERN AND SOUTHERN AREAS. WIDESPREAD SEVERE WEATHER WITH THIS WAVE IS NOT ANTICIPATED AS SHOWERS/STORMS TO THE NORTH WILL BE ELEVATED. IT LOOKS LIKE AFTER THIS ACTIVITY MOVES THROUGH...THERE COULD BE A SHORT BREAK BEFORE THE MORE ORGANIZED ACTIVITY ASSOCIATED WITH THE UPPER TROUGH MOVES THROUGH LATER THIS EVENING AND TONIGHT. THIS BREAK...IF IT OCCURS...WOULD LAST THE LONGEST FOR POINTS SOUTH AND EAST ABD THERE MAY NOT BE MUCH OF A BREAK IN AREAS NORTH AND WEST. THE TIMING ON THIS ROUND OF MORE ORGANIZED THUNDERSTORM ACTIVITY IS AFTER 7-8 PM IN THE WEST...AND AFTER 9 PM CLOSER TO CHICAGO. CURRENT SHORT TERM RUNS OF THE HRRR/RAP SUGGEST IT COULD BE SLIGHTLY LATER THAN THAT FOR AREAS SOUTH AND EAST OF I-57. THE BEST COMBINATION OF UPPER Q-G FORCING FROM THE UPPER TROUGH AND LOWER FRONTOGENETICAL FORCING ON THE BACK SIDE OF THE SURFACE LOW IS ALONG AND NORTH OF I- 80 FOR THIS SECOND ROUND OF STORMS...WHICH IS MAXIMIZED IN THE LATE EVENING AND EARLY MORNING HOURS WHEN THE PERIOD OF HIGHEST CONCERN FOR HEAVY RAIN EXISTS. MANY AREAS WILL SEE HEAVY RAIN ACTIVITY WITH THIS WAVE...BUT HAVE HELD ONTO THE FLASH FLOOD WATCH FOR THE CURRENT AREAS THAT RECEIVED THE HEAVIEST RAINS LAST NIGHT. LEAST FAVORED AREAS ARE SOUTH AND EAST OF INTERSTATE 57 AND HAVE PLACED HIGHEST QPF IN THE MOST FAVORED FORCING LOCATIONS IN NORTH AND NORTH CENTRAL ILLINOIS. MOST UNSTABLE CAPE IN EXCESS OF 1000 J/KG AND EFFECTIVE SHEAR OF 40+ KT SUGGEST THE POTENTIAL FOR SEVERE HAIL AND LOCALLY STRONG WINDS AGAIN WITH THE LATER EVENING STORMS...WITH THE WIND THREAT CONTINGENT ON STORMS EVOLVING INTO A LINE. THE SURFACE LOW CONTINUES DEEPENING OVERNIGHT AS IT MOVES NORTHEASTWARD. THE COLD FRONT SPREADS IN FROM NORTHWEST TO SOUTHEAST WHICH SHOULD EASE SHOWER/STORM THREAT OVERNIGHT. BRISK NORTHWEST WINDS WILL USHER IN A MUCH COOLER AND DRIER AIRMASS. KMD && .LONG TERM... 236 PM CDT SATURDAY THROUGH FRIDAY... MID-LEVEL SHORT WAVE TROUGH AND SURFACE FRONTAL SYSTEM ASSOCIATED WITH SHORT TERM RAIN/THUNDERSTORMS WILL BE MOVING OUT OF THE FORECAST AREA EARLY SATURDAY MORNING. LINGERING LOW LEVEL MOISTURE BEHIND THE FRONT AND FORCING ASSOCIATED WITH THE PASSAGE OF THE MID-LEVEL TROUGH MAY ALLOW A FEW SHOWERS/SPRINKLES TO PERSIST MAINLY ACROSS THE FAR SOUTHEAST PARTS OF THE CWA PAST SUNRISE...THOUGH BREEZY NORTH WINDS QUICKLY ADVECT DRIER AIR INTO THE REGION PER FORECAST SOUNDINGS ALLOWING A QUICK END TO ANY PRECIP AND DECREASING CLOUD COVER THROUGH THE LATE MORNING HOURS. WHILE SUNSHINE RETURNS...COOLER TEMPS IN THE UPPER 60S/AROUND 70 AND BREEZY NORTH WINDS GUSTING AROUND 20 MPH ESPECIALLY IN THE MORNING WILL MAKE FOR AN AUTUMN FEEL. SURFACE HIGH PRESSURE BUILDS ACROSS THE AREA SATURDAY NIGHT...WITH CLEAR SKIES...LIGHT/CALM WINDS AND COOL/DRY AIR MASS...WILL LIKELY PRODUCE SOME CHILLY LOW- MID 40S IN COOLER SPOTS AND HAVE UNDERCUT GUIDANCE/BLENDED TOWARD COOLER MAV MINS. BREEZY NORTH WINDS GUSTING 20-25 MPH SATURDAY MORNING/EARLY AFTERNOON WILL QUICKLY DIMINISH DURING THE AFTERNOON. REST OF EXTENDED PERIOD LOOKS TO REMAIN VERY QUIET...WITH A GRADUAL MODERATING TREND THROUGH MID/LATE WEEK AS UPPER RIDGE DEVELOPS OVER THE SOUTHWESTERN CONUS...AND EVENTUALLY BUILDS NORTHEASTWARD INTO THE GREAT LAKES REGION BY MID-WEEK. SURFACE HIGH SLIDES EAST OF THE AREA BY LATER SUNDAY...THOUGH WESTERN PERIPHERY OF SFC RIDGE AXIS LINGERS ACROSS THE REGION FOR A FEW DAYS. THIS SETS UP A FAIRLY PLEASANT PERIOD OF MILD DAYS WITH TEMPS SLOWLY WARMING FROM THE LOW 70S (UPPER 60S NEAR THE LAKE) TO 75-80/LOW 80S RANGE BY THE LATTER HALF OF THE WEEK...WITH LOWS IN THE 40S/50S MODERATING BACK INTO THE 50S/NEAR 60. NO REAL THREAT OF ORGANIZED RAIN APPEARS AT THIS TIME BEYOND SATURDAY MORNING...UNTIL PERHAPS LATE THURSDAY OR FRIDAY AS A WEAK COLD FRONT SETTLES ACROSS THE UPPER MISSISSIPPI/WESTERN LAKES REGION. SOME MODEL SOLUTIONS KEEP THIS FRONT NORTH OF THE AREA HOWEVER...OR DONT DEVELOP SIGNIFICANT PRECIP ALONG IT...WITH THE UPPER RIDGE RE-BUILDING INTO NEXT WEEKEND. THUS HAVE HELD FORECAST DRY THROUGH FRI AND GIVEN JUST A NOD TO SLIGHTLY COOLER TEMPS ACROSS THE NORTHERN PART OF THE FORECAST AREA BY FRIDAY PER BLENDED GUIDANCE. RATZER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * WIND SHIFT TO NORTH/NORTHWEST EARLY THIS MORNING. * STRONG/GUSTY NORTH/NORTHWEST WINDS THRU MID AFTERNOON. * POSSIBLE NORTHEAST WIND SHIFT/LAKE BREEZE LATE THIS AFTERNOON. * MVFR CIGS THRU MID MORNING...POSSIBLE IFR CIGS EARLY THIS MORNING. CMS //DISCUSSION...UPDATED 06Z... LAST LINE OF THUNDERSTORMS NOW PUSHING EAST OF ORD/MDW AND WILL AFFECT GYY THRU 07Z. COLD FRONT WILL MOVE ACROSS THE TERMINALS OVER THE NEXT FEW HOURS WITH STRONG NORTHWEST WINDS BEHIND THE FRONT ALREADY AT RFD. THESE STRONGER WINDS WILL SPREAD ACROSS THE TERMINALS THIS MORNING WITH WIND DIRECTIONS INTO THE 340-360 RANGE. STILL A CHANCE OF SHOWERS THRU THE OVERNIGHT HOURS AND ESPECIALLY WITH THE FRONTAL PASSAGE. MVFR CIGS APPEAR LIKELY ACROSS THE REGION THRU MID MORNING...BUT A PERIOD OF IFR CIGS IS ALSO POSSIBLE. WINDS WILL SLOWLY DIMINISH THIS AFTERNOON AS THE GRADIENT BEGINS TO WEAKEN. ITS POSSIBLE A LAKE BREEZE MAY DEVELOP AND PUSH INLAND LATE THIS AFTERNOON. IF THIS OCCURS...WINDS MAY TURN NORTHEASTERLY AT ORD/MDW. SPEEDS WITH THIS FRONTAL PASSAGE COULD APPROACH 10KTS...BUT CONFIDENCE IS LOW. CMS //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH FOR WINDS THRU THIS AFTERNOON...LOW FOR LAKE BREEZE AND TIMING LATE THIS AFTERNOON. * MEDIUM FOR IFR CIGS EARLY THIS MORNING. CMS //OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z... SUNDAY THROUGH THURSDAY...VFR. IZZI && .MARINE... 257 PM CDT MAIN MARINE CONCERNS ARE IN THE FIRST 24-36 HOURS OF THE FORECAST THIS AFTERNOON...WITH A PERIOD OF NORTH GALES LIKELY ON CENTRAL AND SOUTHERN LAKE MICHIGAN SATURDAY MORNING. A NEARLY STATIONARY COLD FRONT STRETCHED FROM LOW PRESSURE OVER EASTERN CANADA...SOUTHWEST ACROSS LAKE MICHIGAN TO THE SOUTHERN PLAINS. A SURFACE LOW PRESSURE WAVE WILL LIFT NORTHEAST ALONG THE FRONT THIS EVENING...EVENTUALLY DEEPENING AS IT LIFTS NORTHEAST OF THE LAKE EARLY SATURDAY AND PULLING THE COLD FRONT SOUTHEAST AND CLEAR OF THE LAKE. AS THE LOW DEEPENS OFF TO THE NORTHEAST EARLY SATURDAY...AND HIGH PRESSURE BEGINS TO BUILD EASTWARD ACROSS THE PLAINS...THE COMBINATION OF A TIGHTENING SURFACE PRESSURE GRADIENT AND LOW LEVEL COLD AIR ADVECTION IS EXPECTED TO LEAD TO A BRIEF PERIOD OF 30-35 KT WINDS OVER THE LAKE. GALE FORCE WINDS APPEAR TO BE MOST LIKELY ACROSS CENTRAL AND SOUTHERN LAKE MICHIGAN FROM THE PREDAWN HOURS THROUGH MID-LATE MORNING SATURDAY. WINDS WILL THEN QUICKLY DIMINISH LATER SATURDAY AFTERNOON AND NIGHT AS THE SURFACE HIGH MOVES INTO THE REGION. BEYOND SATURDAY...THE WEATHER PATTERN LOOKS TO REMAIN FAIRLY QUIET WITH THE TRAILING WESTERN PERIPHERY OF THE SURFACE RIDGE AXIS REMAINING OVER THE CENTRAL OR SOUTHERN PART OF THE LAKE...WHILE AN AREA OF LOW PRESSURE PASSES WELL NORTH OF THE LAKES THROUGH MID- WEEK. THIS WILL LIKELY RESULT IN MODEST SOUTH- SOUTHWEST WINDS INCREASING A BIT ON THE NORTH END OF THE LAKE AND PERHAPS GUSTING 15-20 KTS AT TIMES...WHILE REMAINING LIGHTER FARTHER SOUTH. RATZER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010- ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022 UNTIL 7 AM SATURDAY. BEACH HAZARDS STATEMENT...ILZ006-ILZ014...4 AM SATURDAY TO 10 PM SATURDAY. IN...BEACH HAZARDS STATEMENT...INZ001-INZ002...4 AM SATURDAY TO 10 PM SATURDAY. LM...GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777- LMZ779...4 AM SATURDAY TO 1 PM SATURDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
1202 PM CDT SAT SEP 19 2015 ...UPDATE TO AVIATION... .SYNOPSIS... ISSUED AT 900 AM CDT SAT SEP 19 2015 WV Imagery and 12Z upper air analysis indicate a general westerly flow aloft prevailing across the Western High Plains. Meanwhile, a weak upper level shortwave trough is moving east- southeast across eastern Montana and northern Wyoming. Near the surface, a broad area of high pressure is shifting eastward across Nebraska and Kansas. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 111 AM CDT SAT SEP 19 2015 The main challenge in the short term will be low stratus potential up in the northeast zones (particularly around Hays) and if it will impact temperatures at all. A secondary push of cooler air was making its way south into southwest Kansas with a slight bump in winds from the north. On the 11-3.9u imagery during the overnight hours, we were watching an area of stratus advance south- southwestward toward north central KS. The HRRR suggests that this will reach as far southwest as a Dighton to Dodge City line by 14z. This may be a bit ambitious, but there is certainly some merit to this prog as there is some better low level moisture across central/south central Nebraska that wrapped around the low...which will likely continue to advect southwestward through the early morning hours. We will bump up the clouds in the Sky grids to reflect this latest thinking, especially northeast of the Dighton to Dodge City line. Any low stratus should erode by late morning given how shallow it will be. Temperatures today, with the fresh Canadian airmass in place, will only top out in the lower to mid 70s. Will go with slightly cooler temps in the north where low morning clouds will likely delay the diurnal warmup. Advancing to tonight, we will see low level winds turn back around to the south in response to another loosely organized Pacific system moving into the Northern Rockies. Some marginal moisture will return via the "scenic route" (Eastern New Mexico/western TX-OK Panhandles), and increased deformation/convergence in the 700-800mb layer will promote some elevated showers and isolated thunderstorms after 06z Sunday. We will maintain the 20-30 POPs across mainly the western third of the forecast area late tonight, with low Chance POPs between the Arkansas River and the OK border in the 12-18z Sunday time frame. .LONG TERM...(Sunday THROUGH Friday) ISSUED AT 352 AM CDT SAT SEP 19 2015 Our region of the world will once again see a warming trend going into next week as the primary polar jet shifts back to the north and mid level heights rise across the Southern and Central Rockies/adjacent High Plains. During the slow transition back into above-average temperatures, we will see low chances for precipitation, particularly early Sunday as one last shortwave trough ripples through the longwave trough. Highs Sunday will be tricky, and we feel that portions of south central Kansas, especially, will stay stuck in the 60s to lower 70s with elevated convection and stratus clouds lingering through at least the middle part of the day. The lee trough comes back strong by Monday and will be a quasi- steady feature through at least Wednesday. Afternoon temperatures will gradually increase each day with highs in the lower 90s in some locations. The global spectral models suggest a subtropical shortwave trough ejecting from the Baja California region into Rockies which will bring some mid level moisture across into the High Plains. We will have some Slight Chance to Chance POPs in the grids Wednesday Night through Thursday Night, but at this point, it does not look like a real good opportunity for widespread beneficial rainfall across our region given the degree of downslope momentum in the middle troposphere and the general weak nature of the subtropical system to begin with. Beyond mid-week, it certainly looks like we will continue the theme of above average temperatures across the Rockies and adjacent High Plains in the final days of September with both the GFS and the ECMWF showing some semblance of a longwave trough across western North America leading to fairly strong (warm and dry) southwest momentum across the Rockies. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Sunday AFTERNOON) ISSUED AT 1200 PM CDT SAT SEP 19 2015 VFR conditions will prevail at all TAF sites through early Sunday morning. Light northeasterly winds will prevail across western Kansas this afternoon as a surface high moves eastward across Nebraska and northern Kansas. Winds will then become more easterly 5 to 15kt this evening as the surface high pushes east into Iowa and northern Missouri, and more southeasterly early Sunday as it lifts northeastward into the Great Lakes Region. && .PRELIMINARY POINT TEMPS/POPS... DDC 73 55 76 58 / 0 10 10 0 GCK 74 53 81 57 / 0 10 10 0 EHA 75 50 85 56 / 0 10 10 0 LBL 75 54 85 58 / 0 20 10 0 HYS 71 52 79 59 / 0 10 10 0 P28 75 58 76 60 / 0 20 20 0 && .DDC Watches/Warnings/Advisories... NONE. && $$ SYNOPSIS...JJohnson SHORT TERM...Umscheid LONG TERM...Umscheid AVIATION...JJohnson
AREA FORECAST DISCUSSION
NWS GOODLAND KS
945 AM MDT SAT SEP 19 2015 .UPDATE... ISSUED AT 938 AM MDT SAT SEP 19 2015 JUST COMPLETED AN UPDATE. MODELS NOT DOING WELL WITH THE STRENGTH POSITION OF THE SURFACE RIDGE OVER THE AREA AND ALSO THE STRATUS DECK OVER THE EASTERN THIRD OF THE AREA. SURFACE IS STRONGER AND FURTHER WEST THAN WHAT OUTPUT IS INDICATING. SO A SHIFTING TO SOUTHERLY WINDS WILL BE SLOWER...ESPECIALLY FOR THE EASTERN HALF. THICK STRATUS STILL OVER THE EAST AND IS SLOWING DOWN TEMPERATURE RISE. NEWER DATA IS HOLDING ONTO THIS A LITTLE LONGER THAN INDICATED. ALSO MID LEVEL WARM AIR ADVECTION OVER THE COLD DOME AND A WEAK SHORTWAVE TROUGH ARE CREATING A DECENT AREA OF MID LEVEL CLOUD COVER. THIS AREA OF CLOUDS SHOULD MOVE TOWARD THE EAST ...OVER THE STRATUS FIELD. MORNING SOUNDINGS ALSO SHOWING A STRONG INVERSION THIS MORNING. SO LOWERED HIGH TEMPERATURES ACROSS MY NEBRASKA AND KANSAS COUNTIES BECAUSE OF THE CLOUD COVER AND A LESS FAVORABLE WIND FIELD. INCREASED THE CLOUD COVER TO MATCH UP WITH REALITY AND KEPT IT AROUND LONGER AS WELL. UPDATED THE WINDS PER THE NAM WHO IS THE CLOSEST TO REALITY AT THIS TIME. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 208 AM MDT SAT SEP 19 2015 AFTER A CHILLY MORNING...PATCHY FOG AND LOW CLOUDS WILL DISSIPATE WITH MOSTLY SUNNY SKIES BY THE AFTERNOON. HIGH TEMPERATURES WILL BE NEAR SEASONAL NORMALS. TONIGHT...SHORTWAVE EMBEDDED IN ZONAL FLOW ACROSS THE NORTHERN CONUS WILL RESULT IN WEAK SYNOPTIC SCALE LIFT. HOWEVER MOISTURE WILL BE LIMITED AND NONE OF THE MESOSCALE MODELS GENERATE PRECIPITATION...SO WILL REMOVE MENTION OF THUNDERSTORMS AND KEEP POPS AT 10 PERCENT. UPPER RIDGE WILL REBUILD OVER THE REGION SUNDAY AND MONDAY WITH DRY CONDITIONS AND TEMPERATURES WARMING BACK INTO THE 80S ON SUNDAY AND NEAR 90 ON MONDAY. RELATIVE HUMIDITY VALUES WILL DROP TO NEAR 15 PERCENT PRIMARILY IN EASTERN COLORADO BOTH DAYS...BUT WIND SPEEDS WILL BE RELATIVELY LIGHT SO DO NOT EXPECT TO REACH RED FLAG CRITERIA. .LONG TERM...(TUESDAY THROUGH FRIDAY) ISSUED AT 208 AM MDT SAT SEP 19 2015 UPPER LEVEL RIDGING IS OVER THE AREA AT THE START OF THE EXTENDED PERIOD WITH A LEE TROUGH DEVELOPED NEAR THE COLORADO/KANSAS BORDER AT THE SURFACE. THIS WILL KEEP THE FORECAST DRY FOR TUESDAY/TUESDAY NIGHT AS SOUTHERLY SURFACE WINDS BRING WARM TEMPERATURES TO THE REGION. SOUTHWEST FLOW ALOFT WILL CARRY TROPICAL MOISTURE ONTO THE SOUTHWESTERN CONUS FROM THE BAJA PENINSULA ON TUESDAY...WHICH WILL CONTINUE NORTHEAST TOWARDS THE HIGH PLAINS. THIS COINCIDES WITH AN UPPER LEVEL LOW PRESSURE SYSTEM COMING ONTO THE SOUTHERN CALIFORNIA COAST BEFORE WEAKENING TO AN OPEN WAVE AS IT APPROACHES THE REGION. MULTIPLE SHORTWAVES DEVELOP WITHIN THIS SOUTHWEST FLOW ALOFT...IMPACTING THE FORECAST AREA WEDNESDAY THROUGH THURSDAY NIGHT. HOWEVER...MODELS DISAGREE ON THE TIMING AND PLACEMENT OF THESE DISTURBANCES...SO THIS WILL HAVE TO BE MONITORED. KEPT SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS DURING THE WEDNESDAY TO THURSDAY NIGHT TIME FRAME. UPPER LEVEL RIDGING APPEARS TO REBUILD ON FRIDAY...BRINGING DRY CONDITIONS BACK TO THE FORECAST. A VERY GRADUAL COOLING TREND IS EXPECTED FOR THE EXTENDED PERIOD WITH HIGHS IN THE UPPER 80S TO LOW 90S ON TUESDAY DECREASING THROUGH THE WORK WEEK TO THE LOW 80S ON FRIDAY. A SIMILAR TREND WILL BE SEEN WITH LOW TEMPERATURES WHICH WILL RANGE FROM THE 50S TO MID 60S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 519 AM MDT SAT SEP 19 2015 LOW CLOUDS WILL IMPACT KMCK WITH IFR CEILINGS THROUGH LATE MORNING BEFORE CLEARING. UNCERTAIN IF THE LOW CLOUDS WILL MAKE IT AS FAR AS KGLD...BUT WILL CONTINUE TO MONITOR AS SATELLITE SHOWS THEM SPREADING QUICKLY WEST. LATEST RUN OF THE HRRR HAS THEM REACHING TO ABOUT COLBY BEFORE DISSIPATING AFTER 15Z. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...BULLER SHORT TERM...024 LONG TERM...JBH AVIATION...024
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
902 AM CDT SAT SEP 19 2015 ...UPDATE TO SYNOPSIS... .SYNOPSIS... ISSUED AT 900 AM CDT SAT SEP 19 2015 WV Imagery and 12Z upper air analysis indicate a general westerly flow aloft prevailing across the Western High Plains. Meanwhile, a weak upper level shortwave trough is moving east- southeast across eastern Montana and northern Wyoming. Near the surface, a broad area of high pressure is shifting eastward across Nebraska and Kansas. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 111 AM CDT SAT SEP 19 2015 The main challenge in the short term will be low stratus potential up in the northeast zones (particularly around Hays) and if it will impact temperatures at all. A secondary push of cooler air was making its way south into southwest Kansas with a slight bump in winds from the north. On the 11-3.9u imagery during the overnight hours, we were watching an area of stratus advance south- southwestward toward north central KS. The HRRR suggests that this will reach as far southwest as a Dighton to Dodge City line by 14z. This may be a bit ambitious, but there is certainly some merit to this prog as there is some better low level moisture across central/south central Nebraska that wrapped around the low...which will likely continue to advect southwestward through the early morning hours. We will bump up the clouds in the Sky grids to reflect this latest thinking, especially northeast of the Dighton to Dodge City line. Any low stratus should erode by late morning given how shallow it will be. Temperatures today, with the fresh Canadian airmass in place, will only top out in the lower to mid 70s. Will go with slightly cooler temps in the north where low morning clouds will likely delay the diurnal warmup. Advancing to tonight, we will see low level winds turn back around to the south in response to another loosely organized Pacific system moving into the Northern Rockies. Some marginal moisture will return via the "scenic route" (Eastern New Mexico/western TX-OK Panhandles), and increased deformation/convergence in the 700-800mb layer will promote some elevated showers and isolated thunderstorms after 06z Sunday. We will maintain the 20-30 POPs across mainly the western third of the forecast area late tonight, with low Chance POPs between the Arkansas River and the OK border in the 12-18z Sunday time frame. .LONG TERM...(Sunday THROUGH Friday) ISSUED AT 352 AM CDT SAT SEP 19 2015 Our region of the world will once again see a warming trend going into next week as the primary polar jet shifts back to the north and mid level heights rise across the Southern and Central Rockies/adjacent High Plains. During the slow transition back into above-average temperatures, we will see low chances for precipitation, particularly early Sunday as one last shortwave trough ripples through the longwave trough. Highs Sunday will be tricky, and we feel that portions of south central Kansas, especially, will stay stuck in the 60s to lower 70s with elevated convection and stratus clouds lingering through at least the middle part of the day. The lee trough comes back strong by Monday and will be a quasi- steady feature through at least Wednesday. Afternoon temperatures will gradually increase each day with highs in the lower 90s in some locations. The global spectral models suggest a subtropical shortwave trough ejecting from the Baja California region into Rockies which will bring some mid level moisture across into the High Plains. We will have some Slight Chance to Chance POPs in the grids Wednesday Night through Thursday Night, but at this point, it does not look like a real good opportunity for widespread beneficial rainfall across our region given the degree of downslope momentum in the middle troposphere and the general weak nature of the subtropical system to begin with. Beyond mid-week, it certainly looks like we will continue the theme of above average temperatures across the Rockies and adjacent High Plains in the final days of September with both the GFS and the ECMWF showing some semblance of a longwave trough across western North America leading to fairly strong (warm and dry) southwest momentum across the Rockies. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Sunday MORNING) ISSUED AT 556 AM CDT SAT SEP 19 2015 Surface high pressure centered in Nebraska will move into Iowa by 00Z. Pressures will begin to fall in the lee of the Rockies this afternoon as an upper level trough moves from Idaho into eastern Wyoming. An area of stratus with ceilings near 015 extending from southeast South Dakota into northern Kansas will propagate south and gradually erode during the morning hours. Ceilings from 010 to 015 will persist in HYS through the morning and scatter out around 17Z. The stratus will approach DDC by 14Z but should remain mostly east of the TAF location. Other than the area of stratus, VFR conditions will prevail through 12Z Sunday. A few showers and possibly a thunderstorm with bases near 070 can be expected after 06Z in GCK and around 09Z in DDC. && .PRELIMINARY POINT TEMPS/POPS... DDC 73 55 76 58 / 0 10 10 0 GCK 74 53 81 57 / 0 10 10 0 EHA 74 50 85 56 / 0 10 10 0 LBL 75 54 85 58 / 0 20 10 0 HYS 71 52 79 59 / 0 10 10 0 P28 74 58 76 60 / 0 20 20 0 && .DDC Watches/Warnings/Advisories... NONE. && $$ SYNOPSIS...JJohnson SHORT TERM...Umscheid LONG TERM...Umscheid AVIATION...Ruthi
AREA FORECAST DISCUSSION
NWS GOODLAND KS
522 AM MDT SAT SEP 19 2015 .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 208 AM MDT SAT SEP 19 2015 AFTER A CHILLY MORNING...PATCHY FOG AND LOW CLOUDS WILL DISSIPATE WITH MOSTLY SUNNY SKIES BY THE AFTERNOON. HIGH TEMPERATURES WILL BE NEAR SEASONAL NORMALS. TONIGHT...SHORTWAVE EMBEDDED IN ZONAL FLOW ACROSS THE NORTHERN CONUS WILL RESULT IN WEAK SYNOPTIC SCALE LIFT. HOWEVER MOISTURE WILL BE LIMITED AND NONE OF THE MESOSCALE MODELS GENERATE PRECIPITATION...SO WILL REMOVE MENTION OF THUNDERSTORMS AND KEEP POPS AT 10 PERCENT. UPPER RIDGE WILL REBUILD OVER THE REGION SUNDAY AND MONDAY WITH DRY CONDITIONS AND TEMPERATURES WARMING BACK INTO THE 80S ON SUNDAY AND NEAR 90 ON MONDAY. RELATIVE HUMIDITY VALUES WILL DROP TO NEAR 15 PERCENT PRIMARILY IN EASTERN COLORADO BOTH DAYS...BUT WIND SPEEDS WILL BE RELATIVELY LIGHT SO DO NOT EXPECT TO REACH RED FLAG CRITERIA. .LONG TERM...(TUESDAY THROUGH FRIDAY) ISSUED AT 208 AM MDT SAT SEP 19 2015 UPPER LEVEL RIDGING IS OVER THE AREA AT THE START OF THE EXTENDED PERIOD WITH A LEE TROUGH DEVELOPED NEAR THE COLORADO/KANSAS BORDER AT THE SURFACE. THIS WILL KEEP THE FORECAST DRY FOR TUESDAY/TUESDAY NIGHT AS SOUTHERLY SURFACE WINDS BRING WARM TEMPERATURES TO THE REGION. SOUTHWEST FLOW ALOFT WILL CARRY TROPICAL MOISTURE ONTO THE SOUTHWESTERN CONUS FROM THE BAJA PENINSULA ON TUESDAY...WHICH WILL CONTINUE NORTHEAST TOWARDS THE HIGH PLAINS. THIS COINCIDES WITH AN UPPER LEVEL LOW PRESSURE SYSTEM COMING ONTO THE SOUTHERN CALIFORNIA COAST BEFORE WEAKENING TO AN OPEN WAVE AS IT APPROACHES THE REGION. MULTIPLE SHORTWAVES DEVELOP WITHIN THIS SOUTHWEST FLOW ALOFT...IMPACTING THE FORECAST AREA WEDNESDAY THROUGH THURSDAY NIGHT. HOWEVER...MODELS DISAGREE ON THE TIMING AND PLACEMENT OF THESE DISTURBANCES...SO THIS WILL HAVE TO BE MONITORED. KEPT SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS DURING THE WEDNESDAY TO THURSDAY NIGHT TIME FRAME. UPPER LEVEL RIDGING APPEARS TO REBUILD ON FRIDAY...BRINGING DRY CONDITIONS BACK TO THE FORECAST. A VERY GRADUAL COOLING TREND IS EXPECTED FOR THE EXTENDED PERIOD WITH HIGHS IN THE UPPER 80S TO LOW 90S ON TUESDAY DECREASING THROUGH THE WORK WEEK TO THE LOW 80S ON FRIDAY. A SIMILAR TREND WILL BE SEEN WITH LOW TEMPERATURES WHICH WILL RANGE FROM THE 50S TO MID 60S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 519 AM MDT SAT SEP 19 2015 LOW CLOUDS WILL IMPACT KMCK WITH IFR CEILINGS THROUGH LATE MORNING BEFORE CLEARING. UNCERTAIN IF THE LOW CLOUDS WILL MAKE IT AS FAR AS KGLD...BUT WILL CONTINUE TO MONITOR AS SATELLITE SHOWS THEM SPREADING QUICKLY WEST. LATEST RUN OF THE HRRR HAS THEM REACHING TO ABOUT COLBY BEFORE DISSIPATING AFTER 15Z. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...024 LONG TERM...JBH AVIATION...024
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
557 AM CDT SAT SEP 19 2015 ...Updated Aviation Section... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 111 AM CDT SAT SEP 19 2015 The main challenge in the short term will be low stratus potential up in the northeast zones (particularly around Hays) and if it will impact temperatures at all. A secondary push of cooler air was making its way south into southwest Kansas with a slight bump in winds from the north. On the 11-3.9u imagery during the overnight hours, we were watching an area of stratus advance south- southwestward toward north central KS. The HRRR suggests that this will reach as far southwest as a Dighton to Dodge City line by 14z. This may be a bit ambitious, but there is certainly some merit to this prog as there is some better low level moisture across central/south central Nebraska that wrapped around the low...which will likely continue to advect southwestward through the early morning hours. We will bump up the clouds in the Sky grids to reflect this latest thinking, especially northeast of the Dighton to Dodge City line. Any low stratus should erode by late morning given how shallow it will be. Temperatures today, with the fresh Canadian airmass in place, will only top out in the lower to mid 70s. Will go with slightly cooler temps in the north where low morning clouds will likely delay the diurnal warmup. Advancing to tonight, we will see low level winds turn back around to the south in response to another loosely organized Pacific system moving into the Northern Rockies. Some marginal moisture will return via the "scenic route" (Eastern New Mexico/western TX-OK Panhandles), and increased deformation/convergence in the 700-800mb layer will promote some elevated showers and isolated thunderstorms after 06z Sunday. We will maintain the 20-30 POPs across mainly the western third of the forecast area late tonight, with low Chance POPs between the Arkansas River and the OK border in the 12-18z Sunday time frame. .LONG TERM...(Sunday THROUGH Friday) ISSUED AT 352 AM CDT SAT SEP 19 2015 Our region of the world will once again see a warming trend going into next week as the primary polar jet shifts back to the north and mid level heights rise across the Southern and Central Rockies/adjacent High Plains. During the slow transition back into above-average temperatures, we will see low chances for precipitation, particularly early Sunday as one last shortwave trough ripples through the longwave trough. Highs Sunday will be tricky, and we feel that portions of south central Kansas, especially, will stay stuck in the 60s to lower 70s with elevated convection and stratus clouds lingering through at least the middle part of the day. The lee trough comes back strong by Monday and will be a quasi- steady feature through at least Wednesday. Afternoon temperatures will gradually increase each day with highs in the lower 90s in some locations. The global spectral models suggest a subtropical shortwave trough ejecting from the Baja California region into Rockies which will bring some mid level moisture across into the High Plains. We will have some Slight Chance to Chance POPs in the grids Wednesday Night through Thursday Night, but at this point, it does not look like a real good opportunity for widespread beneficial rainfall across our region given the degree of downslope momentum in the middle troposphere and the general weak nature of the subtropical system to begin with. Beyond mid-week, it certainly looks like we will continue the theme of above average temperatures across the Rockies and adjacent High Plains in the final days of September with both the GFS and the ECMWF showing some semblance of a longwave trough across western North America leading to fairly strong (warm and dry) southwest momentum across the Rockies. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Sunday MORNING) ISSUED AT 556 AM CDT SAT SEP 19 2015 Surface high pressure centered in Nebraska will move into Iowa by 00Z. Pressures will begin to fall in the lee of the Rockies this afternoon as an upper level trough moves from Idaho into eastern Wyoming. An area of stratus with ceilings near 015 extending from southeast South Dakota into northern Kansas will propagate south and gradually erode during the morning hours. Ceilings from 010 to 015 will persist in HYS through the morning and scatter out around 17Z. The stratus will approach DDC by 14Z but should remain mostly east of the TAF location. Other than the area of stratus, VFR conditions will prevail through 12Z Sunday. A few showers and possibly a thunderstorm with bases near 070 can be expected after 06Z in GCK and around 09Z in DDC. && .PRELIMINARY POINT TEMPS/POPS... DDC 73 55 75 59 / 0 20 30 10 GCK 74 53 80 58 / 10 30 30 10 EHA 74 50 84 57 / 10 20 20 10 LBL 75 54 84 59 / 10 30 20 10 HYS 70 52 78 60 / 0 10 20 10 P28 74 58 75 61 / 0 20 20 10 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Umscheid AVIATION...Ruthi
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
353 AM CDT SAT SEP 19 2015 ...UPDATED LONG TERM SECTION... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 111 AM CDT SAT SEP 19 2015 The main challenge in the short term will be low stratus potential up in the northeast zones (particularly around Hays) and if it will impact temperatures at all. A secondary push of cooler air was making its way south into southwest Kansas with a slight bump in winds from the north. On the 11-3.9u imagery during the overnight hours, we were watching an area of stratus advance south- southwestward toward north central KS. The HRRR suggests that this will reach as far southwest as a Dighton to Dodge City line by 14z. This may be a bit ambitious, but there is certainly some merit to this prog as there is some better low level moisture across central/south central Nebraska that wrapped around the low...which will likely continue to advect southwestward through the early morning hours. We will bump up the clouds in the Sky grids to reflect this latest thinking, especially northeast of the Dighton to Dodge City line. Any low stratus should erode by late morning given how shallow it will be. Temperatures today, with the fresh Canadian airmass in place, will only top out in the lower to mid 70s. Will go with slightly cooler temps in the north where low morning clouds will likely delay the diurnal warmup. Advancing to tonight, we will see low level winds turn back around to the south in response to another loosely organized Pacific system moving into the Northern Rockies. Some marginal moisture will return via the "scenic route" (Eastern New Mexico/western TX-OK Panhandles), and increased deformation/convergence in the 700-800mb layer will promote some elevated showers and isolated thunderstorms after 06z Sunday. We will maintain the 20-30 POPs across mainly the western third of the forecast area late tonight, with low Chance POPs between the Arkansas River and the OK border in the 12-18z Sunday time frame. .LONG TERM...(Sunday THROUGH Friday) ISSUED AT 352 AM CDT SAT SEP 19 2015 Our region of the world will once again see a warming trend going into next week as the primary polar jet shifts back to the north and mid level heights rise across the Southern and Central Rockies/adjacent High Plains. During the slow transition back into above-average temperatures, we will see low chances for precipitation, particularly early Sunday as one last shortwave trough ripples through the longwave trough. Highs Sunday will be tricky, and we feel that portions of south central Kansas, especially, will stay stuck in the 60s to lower 70s with elevated convection and stratus clouds lingering through at least the middle part of the day. The lee trough comes back strong by Monday and will be a quasi- steady feature through at least Wednesday. Afternoon temperatures will gradually increase each day with highs in the lower 90s in some locations. The global spectral models suggest a subtropical shortwave trough ejecting from the Baja California region into Rockies which will bring some mid level moisture across into the High Plains. We will have some Slight Chance to Chance POPs in the grids Wednesday Night through Thursday Night, but at this point, it does not look like a real good opportunity for widespread beneficial rainfall across our region given the degree of downslope momentum in the middle troposphere and the general weak nature of the subtropical system to begin with. Beyond mid-week, it certainly looks like we will continue the theme of above average temperatures across the Rockies and adjacent High Plains in the final days of September with both the GFS and the ECMWF showing some semblance of a longwave trough across western North America leading to fairly strong (warm and dry) southwest momentum across the Rockies. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Saturday NIGHT) ISSUED AT 1134 PM CDT FRI SEP 18 2015 Aviation weather will be fairly tranquil as high pressure continues to settle in across western Kansas. There is a secondary surge of stronger north wind moving in, so expect wind speeds to pick back up at GCK and DDC to the 12 to 16 knot range for a few hours in the 06 to 10z time frame, but they will drop back to below 10 knots by daybreak. Winds will remain light through the day Saturday, but winds will gradually pick back up (from the southeast) late in the day in response to a redeveloping leeside trough. VFR conditions are expected to prevail with the dry airmass in place now. && .PRELIMINARY POINT TEMPS/POPS... DDC 73 55 75 59 / 0 20 30 10 GCK 74 53 80 58 / 10 30 30 10 EHA 74 50 84 57 / 10 20 20 10 LBL 75 54 84 59 / 10 30 20 10 HYS 70 52 78 60 / 0 10 20 10 P28 74 58 75 61 / 0 20 20 10 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Umscheid AVIATION...Umscheid
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
112 AM CDT SAT SEP 19 2015 ...Updated Short Term Section... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 111 AM CDT SAT SEP 19 2015 The main challenge in the short term will be low stratus potential up in the northeast zones (particularly around Hays) and if it will impact temperatures at all. A secondary push of cooler air was making its way south into southwest Kansas with a slight bump in winds from the north. On the 11-3.9u imagery during the overnight hours, we were watching an area of stratus advance south- southwestward toward north central KS. The HRRR suggests that this will reach as far southwest as a Dighton to Dodge City line by 14z. This may be a bit ambitious, but there is certainly some merit to this prog as there is some better low level moisture across central/south central Nebraska that wrapped around the low...which will likely continue to advect southwestward through the early morning hours. We will bump up the clouds in the Sky grids to reflect this latest thinking, especially northeast of the Dighton to Dodge City line. Any low stratus should erode by late morning given how shallow it will be. Temperatures today, with the fresh Canadian airmass in place, will only top out in the lower to mid 70s. Will go with slightly cooler temps in the north where low morning clouds will likely delay the diurnal warmup. Advancing to tonight, we will see low level winds turn back around to the south in response to another loosely organized Pacific system moving into the Northern Rockies. Some marginal moisture will return via the "scenic route" (Eastern New Mexico/western TX-OK Panhandles), and increased deformation/convergence in the 700-800mb layer will promote some elevated showers and isolated thunderstorms after 06z Sunday. We will maintain the 20-30 POPs across mainly the western third of the forecast area late tonight, with low Chance POPs between the Arkansas River and the OK border in the 12-18z Sunday time frame. .LONG TERM...(Saturday NIGHT THROUGH Friday) ISSUED AT 220 PM CDT FRI SEP 18 2015 High temperatures have most recently been best handled by the bias corrected ECMWF MOS. Further past the weekend temperatures will rapidly bounce back toward around 90 degrees on Monday and Tuesday as the southerly flow becomes reestablished. Recent forecasts have included chances for thunderstorms centered around the late Sunday timeframe. This potential still looks favorable with rapid return flow along a redeveloped surface trough over the central High Plains and differential vorticity advection across the area. The next appreciable chance returns on Wednesday or Thursday as the upper flow turn more southwesterly with stronger embedded shortwaves helping to create lee cyclones over the northern plains region. Breezy and warm should also be the character of the period with strong southwest downslope flow for several days. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Saturday NIGHT) ISSUED AT 1134 PM CDT FRI SEP 18 2015 Aviation weather will be fairly tranquil as high pressure continues to settle in across western Kansas. There is a secondary surge of stronger north wind moving in, so expect wind speeds to pick back up at GCK and DDC to the 12 to 16 knot range for a few hours in the 06 to 10z time frame, but they will drop back to below 10 knots by daybreak. Winds will remain light through the day Saturday, but winds will gradually pick back up (from the southeast) late in the day in response to a redeveloping leeside trough. VFR conditions are expected to prevail with the dry airmass in place now. && .PRELIMINARY POINT TEMPS/POPS... DDC 73 55 80 59 / 0 20 30 10 GCK 74 53 81 58 / 10 30 30 10 EHA 74 50 83 57 / 10 20 20 10 LBL 75 54 81 59 / 10 30 20 10 HYS 70 52 84 60 / 0 10 20 10 P28 74 58 79 61 / 0 20 20 10 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Russell AVIATION...Umscheid
AREA FORECAST DISCUSSION
NWS JACKSON KY
800 PM EDT SUN SEP 20 2015 .UPDATE... ISSUED AT 800 PM EDT SUN SEP 20 2015 UPDATED FORECAST TO REFINE THE SKY COVER BASED ON THE LATEST HI RES MODELS. HRRR IS BACKING OFF ON SHOWERS MAKING INTO OUR FAR EAST LATE TONIGHT. HOWEVER...STILL OPTING TO HOLD ONTO A SLIGHT CHANCE OF A SHOWER FOR PIKE/HARLAN/LETCHER COUNTIES. OTHERWISE...REST OF THE AREA WILL REMAIN DRY. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 400 PM EDT SUN SEP 20 2015 A COLD FRONT DISSIPATED AS IT MOVED THROUGH OUR REGION LAST EVENING. SURFACE WINDS OUT OF THE NW BEHIND THE FRONT INITIALLY BEGAN TO CARRY IN DRIER AIR. HOWEVER...WITH THE DEMISE OF THE BOUNDARY AND WINDS EVENTUALLY VEERING TOWARD THE NE...THE DRIER AIR HAS HAD TROUBLE MAKING IT ALL THE WAY INTO OUR AREA. LOW CLOUDS HAVE LINGERED ALL DAY NEAR THE BORDER WITH TN AND VA. WITH LOW LEVEL MOISTURE NEARBY A MID/UPPER LEVEL TROUGH DROPPING SOUTHEAST INTO THE REGION IS EXPECTED TO LEAD TO A RESURGENCE OF CLOUDS AND POSSIBLY SOME SHOWERS FOR PORTIONS OF THE CENTRAL APPALACHIANS TONIGHT INTO MONDAY. THIS SHOULD MAINLY BE TO THE EAST OF THE JKL FORECAST AREA...BUT COULD CLIP THE EASTERN TIP OF KY. THIS WOULD PROVIDE A BIT OF INHIBITION FOR TEMPERATURES TO FALL OVERNIGHT AND TO RISE ON MONDAY IN THE EASTERN PART OF THE AREA. MEANWHILE...IN THE WEST SKIES SHOULD BE CLEAR TO PARTLY CLOUDY AND MORNING LOWS A BIT COOLER AND HIGHS ON MONDAY A BIT WARMER WHEN COMPARED TO THE EAST. THE EFFECTS OF THE MID/UPPER LEVEL WAVE ARE EXPECTED TO SHIFT SLIGHTLY EASTWARD MONDAY NIGHT...LEAVING US WITH DRY WEATHER UNDER CLEAR TO PARTLY CLOUDY SKIES AREA WIDE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 400 PM EDT SUN SEP 20 2015 THE EXTENDED PORTION OF THE FORECAST BEGINS ON TUESDAY WITH THE UPPER LEVEL PATTERN DEVELOPING INTO A BROAD RIDGE OVER THE ENTIRE CONUS. THE JET REMAINS POSITIONED NORTH ALONG THE CANADIAN BORDER WITH MOST OF THE UPPER LEVEL WAVES PASSING NORTH OF THE FORECAST AREA FOR MUCH OF THE EXTENDED PERIOD. HOWEVER...AN UPPER LOW BECOMING CUT OFF FROM THE UPPER LEVEL FLOW UNDER THE RIDGE WILL MEANDER THROUGH THE FRONT RANGE AND INTO THE SOUTHERN PLAINS. ALSO DURING THIS TIME...A CUT OFF LOW IN THE SOUTHEAST THAT MEANDERS JUST OFF THE FL PANHANDLE WILL THEN EVENTUALLY DRIFT NORTH AGAIN AND POTENTIALLY BRING SOME UPPER LEVEL SUPPORT INTO EASTERN KENTUCKY BY THE END OF THE EXTENDED. NEAR THE SURFACE...HIGH PRESSURE WILL BE THE DOMINANT WEATHER FEATURE THROUGH THE EXTENDED FORECAST PERIOD. WITH THE EXCEPTION OF THE WEAK SURFACE BOUNDARY ALONG THE APPALACHIAN RANGE AND A WEAK UPPER LEVEL DISTURBANCE PROVIDING SOME WEAK FORCING FOR AFTERNOON SHOWER DEVELOPMENT ON TUESDAY...WEDNESDAY THROUGH FRIDAY SHOULD REMAIN DRY AT THIS POINT WITH THE SURFACE HIGH QUITE STRONG ENOUGH TO KEEP ANY SURFACE FORCING FROM MAKING IT INTO THE AREA. THE ONLY EXCEPTION WILL BE A SLIGHT CHANCE OF PRECIP THAT DEVELOPS WITH THE ASSIST OF THE HIGHER TERRAIN IN THE EAST. IN FACT...WILL TREND BELOW THE SUPER BLEND SOLUTION THROUGH SATURDAY. THE CURRENT PATTERN CERTAINLY DOES SEEM TO TREND DRIER AND AS IS THE TIME OF THE YEAR AS WELL. SO WENT BELOW SUPERBLEND VALUES AND THIS WAS AGREED BY NEIGHBORING OFFICES AS WELL. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 800 PM EDT SUN SEP 20 2015 SOME LOW LEVEL CLOUDS WILL CONTINUE TO IMPACT FAR SOUTHEASTERN KENTUCKY OVERNIGHT. HOWEVER...NOT CONFIDENT THEY WILL BE ROBUST ENOUGH TO IMPACT THE TAF SITES. THUS...LEFT TAF SITES MAINLY VFR THROUGH THE NIGHT...WITH THE EXCEPTION OF KSME...WHICH COULD SEE A LITTLE FOG IF SKIES CAN CLEAR OUT AS ADVERTISED BY THE MODELS. ANY FOG AND LINGERING CLOUD COVER SHOULD SLOWLY EXIT ON MONDAY...WITH VFR CONDITIONS EXPECTED. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KAS SHORT TERM...HAL LONG TERM...SHALLENBERGER AVIATION...KAS
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
915 AM MDT SAT SEP 19 2015 .UPDATE... JUST A FEW TWEAKS FOR THE MORNING UPDATE. RAP SOUNDINGS SHOWED GOOD MIXING POTENTIAL TODAY WHICH WILL PRODUCE BREEZY/WINDY CONDITIONS CENTRAL AND W. NOTED KLVM AND KBIL WERE ALREADY GUSTING THIS MORNING...AND EXPECT SUBSIDENCE BEHIND THE DEPARTING SHORTWAVE TO AID IN GUSTY WINDS. THUS HAVE RAISED WIND SPEEDS OVER THE CENTRAL AND W ZONES. NOT MUCH CLOUD COVER EXPECTED TODAY WITH THE WAVE MOVING OUT AND CLOUDS CONFINED TO N OF CANADIAN BORDER WITH THE ZONAL JET. GIVEN THE LIMITED CLOUD COVER AND GOOD MIXING HAVE RAISED HIGH TEMPERATURES IN SEVERAL AREAS TOWARD THE RUC GUIDANCE. DOWNSLOPE FLOW WILL ALSO SUPPORT HIGHER TEMPERATURES. LOWERED CLOUD COVER IN THE GRIDS FOR TODAY. ARTHUR && .SHORT TERM...VALID FOR TDY AND SUN... SHORT WAVE TROUGH MOVING ACROSS OUR FORECAST AREA AT THIS TIME ONLY ABLE TO PRODUCE SOME CLOUD COVER DUE TO DRY LOWER LEVELS. WE WILL SLOWLY TRANSITION TO ZONAL FLOW BEHIND THIS WAVE BY SUNDAY. LEE-SIDE SURFACE TROUGHING THROUGH THE WEEKEND WILL LEAD TO WARMING WITH HIGHS IN THE LOWER TO MID 70S TODAY...FOLLOWED BY UPPER 70S TO LOWER 80S SUNDAY. LOOK FOR STIFF W/SW WINDS LATE MORNING THROUGH AFTERNOON EACH DAY...ESPECIALLY FROM BILLINGS WEST TO LIVINGSTON. PROGGS INDICATE WIND DIRECTION WILL HAVE TOO MUCH OF A WESTERLY COMPONENT FOR ANY SIGNIFICANT GAP EFFECTS AT LIVINGSTON/NYE...BUT WILL CERTAINLY BE WINDY AT TIMES. BT .LONG TERM...VALID FOR MON...TUE...WED...THU...FRI... NO SIGNIFICANT CHANGES IN THE EXTENDED OUTSIDE OF BORDER COLLABORATION AND NEW PERIODS. MODELS CONTINUE IN GOOD AGREEMENT...WITH GENERALLY WARM AND DRY CONDITIONS THROUGH THE WORK WEEK...UNDER ZONAL FLOW ALOFT THROUGH WEDNESDAY. THAT SAID...THERE IS A WEAK SHORTWAVE SLIDES ACROSS THE NORTHERN TIER OF THE CWA MONDAY NIGHT INTO TUESDAY...WITH JUST ENOUGH ENERGY THAT IT COULD BRING A SLIGHT CHANCE OF PRECIP IN THE EASTERN ZONES. SOUTHWEST FLOW BEGINS TO RETURN TO THE REGION WEDNESDAY NIGHT...AS THE REMNANTS OF THE SUB-TROPICAL SYSTEM LIFTING OUT OF THE PACIFIC SOUTHWEST APPEAR TO REACH THE AREA. AT THIS TIME THIS SYSTEM ONLY LOOKS LIKE IT WILL BRING SOME ISOLATED TO SCATTERED MOUNTAIN PRECIP...AND AN ISOLATED CHANCE TO EASTERNMOST ZONES. SOUTHWEST FLOW DEEPENS INTO THE WEEKEND IN ADVANCE OF THE APPROACHING STRONG PACIFIC TROF...SO HAVE KEPT SOME SLIGHT MOUNTAIN POPS IN PLACE IN THE MOUNTAINS. THE REMAINDER OF THE PERIOD IS A BIT MORE UNCERTAIN. TIMING IS A INCONSISTENT AMONGST MODELS WITH THE PROGRESSION OF THE TROF...BUT IN GOOD AGREEMENT ON IMPACTING THE REGION OVER THE WEEKEND AND EARLY NEXT WEEK. THE ECMWF DOES INDICATE A SLOWER PROGRESSION WITH GREATER PRECIP POTENTIAL AT THIS TIME...BUT MUCH CAN CHANGE IN A WEEK. AAG && .AVIATION... WINDS WILL BE INCREASING FROM WEST TO EAST THIS MORNING AND EARLY AFTERNOON ACROSS ALL ROUTES. STRONGEST WINDS WILL BE IN AND AROUND KLVM AND K6SO...WITH GUSTS OF 25 TO 35 KNOTS. GUSTS APPROACHING 20 KNOTS ACROSS EASTERN MONTANA...INCLUDING KBIL...KMLS...AND KBHK. WINDS WILL TAPER OFF AGAIN THIS EVENING. OTHERWISE VFR CONDITIONS WILL PREVAIL OVER THE FEW DAYS...UNDER CLEAR TO PARTLY CLOUDY SKIES. AAG/REIMER && .PRELIMINARY POINT TEMP/POPS... TDY SUN MON TUE WED THU FRI ------------------------------------------------------- BIL 076 050/080 053/077 048/078 054/080 053/080 053/082 0/B 00/B 01/B 11/B 11/B 12/T 22/T LVM 071 043/078 046/075 043/078 047/079 047/079 048/080 0/N 00/N 02/W 11/U 11/B 22/T 23/T HDN 077 045/082 048/080 046/081 051/082 050/083 050/085 0/B 00/B 01/B 11/B 12/W 11/B 11/B MLS 076 049/081 052/078 048/080 052/081 053/080 053/085 0/B 00/U 01/U 22/W 11/B 12/W 12/T 4BQ 076 047/081 049/080 048/081 052/082 052/081 051/085 0/B 00/U 01/U 11/U 12/W 11/B 11/B BHK 074 046/078 050/077 046/074 050/078 051/076 051/080 0/B 00/U 01/U 22/W 12/W 12/T 22/T SHR 074 042/080 046/080 045/083 049/082 048/082 048/085 0/B 00/U 01/U 11/U 12/W 12/T 21/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
334 PM MDT SAT SEP 19 2015 .SYNOPSIS... THE BACKDOOR COLD FRONT THAT MOVED THROUGH THE AREA LAST NIGHT AND THIS MORNING WILL STALL ALONG THE CONTINENTAL DIVIDE AND WEAKEN THIS EVENING. THIS FEATURE WILL BE THE FOCUS FOR A FEW SHOWERS AND THUNDERSTORMS OVER WESTERN NEW MEXICO THROUGH THE EVENING HOURS. DRY AIR WILL MOVE INTO THE STATE FROM THE NORTHWEST ON SUNDAY AS THE FOUR CORNERS HIGH REBUILDS OVER ARIZONA. THE DRY AIR WILL KEEP SHOWERS AND THUNDERSTORMS CONFINED TO THE SOUTHWEST AND SOUTH-CENTRAL MOUNTAINS. SOUTHERLY FLOW BETWEEN A WEAK STORM SYSTEM OFF OF THE FAR SOUTHERN CALIFORNIA COAST AND THE FOUR CORNERS HIGH WILL BRING IN DEEP SUBTROPICAL MOISTURE AND SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS BEGINNING LATE- DAY MONDAY AND CONTINUING THROUGH WEDNESDAY. && .DISCUSSION... BACKDOOR COLD FRONT HAS PUSHED AS FAR WEST AS THE DIVIDE THIS AFTERNOON. ENOUGH WARMING HERE AT THE ABQ SUNPORT...HOWEVER...TO GET SOUTHWEST WINDS TO SURFACE...INDICATING THE AIRMASS IS QUITE SHALLOW AND WILL LIKELY GET MIXED OUT WEST OF THE CENTRAL MTN CHAIN LATE THIS AFTERNOON/EARLY EVENING. A BAND OF CONVECTION HAS DEVELOPED IN NW CATRON COUNTY AND THIS IS THE AREA OF SFC CONVERGENCE AND INSTABILITY THAT THE MODELS ATTEMPT TO BRING NEWD DURING THE EVENING. 18Z NAM12 NOT AT ALL EXCITED ABOUT IT AND WITH NO STRONG UPPER LEVEL LARGE SCALE FORCING TO SPEAK OF...SUSPECT IT`S ON THE RIGHT TRACK. GFS IS ONCE AGAIN OUT TO LUNCH WITH THIS SHALLOW BACKDOOR COLD FRONT SCENARIO. MAIN FORECAST CHANGE FOR SUNDAY WAS TO LOWER PRECIP CHANCES OVER THE SOUTHWEST AND SOUTH-CENTRAL MOUNTAINS. BOTH GFS AND NAM BRING IN SINGLE DIGIT RH AT/NEAR 500MB MAKING IT ALL BUT IMPOSSIBLE FOR CUMULUS UPDRAFTS TO SURVIVE OUTSIDE OF SW CATRON...SW SOCORRO AND SRN LINCOLN COUNTIES SUNDAY AFTERNOON. FAVORED AREA FOR ISOLATED THUNDERSTORMS APPEARS TO BE OVER SRN LINCOLN COUNTY WHERE THE SELY SFC RETURN FLOW PRODUCES SUFFICIENT CONVERGENCE AND MOISTURE ADVECTION. GFS AND NAM TRENDING TOWARD THE SLOWER ECMWF SOLUTION FOR NEXT WEEK. STARTED PROCESS OF LOWERING PRECIP CHANCES MONDAY AS NEARLY ALL MODELS ARE SLOWER WITH THE DEEPER MOISTURE AND PRECIP SHIELD IN THE STRONG SOUTHERLY FLOW BETWEEN A WEAK UPPER LOW SW OF SAN DIEGO AND THE UPPER HIGH OVER FAR W TX/NRN MEXICO. TUESDAY AND TUESDAY NIGHT NOW LOOKING LIKE THE MOST ACTIVE PERIOD AS ALL GLOBAL MODELS PRODUCING WIDESPREAD PRECIP OVER THE LAND OF ENCHANTMENT. 12Z GFS AND ECMWF HAVE NOW COME IN LINE WITH ONE ANOTHER FOR WEDNESDAY THROUGH FRIDAY. BOTH MODELS BRING IN DRIER AIR ON WLY FLOW ALOFT BEGINNING WEDNESDAY AFTERNOON. STILL PLENTY ACTIVE ALONG AND EAST OF THE CENTRAL MOUNTAIN CHAIN WEDNESDAY AFTERNOON BUT DRY AIR WINDS OUT OVER THE NW THIRD. THURSDAY AND FRIDAY LOOK LIKE DOWN DAYS AHEAD OF A HIGH AMPLITUDE UPPER LEVEL TROUGH WHICH BEGINS TO SPREAD SUBTROPICAL MOISTURE NEWD INTO WRN NM SATURDAY...AT LEAST ACCORDING TO THE GFS. ECMWF IS ABOUT 24 HRS SLOWER BUT VERY SIMILAR WITH THE OVERALL UPPER LEVEL PATTERN. LET THE EL NINO GAMES OF 2015 BEGIN. 33 && .FIRE WEATHER... ISOLATED TO SCATTERED AFTERNOON SHOWERS AND THUNDERSTORMS DEVELOPED SOUTH OF THE I40 CORRIDOR AS MID LEVEL MOISTURE SURGED NORTHWARD FROM THE SOUTHERN BAJA PENINSULA...WITH DRIER CONDITIONS ACROSS THE NORTHWEST. WINDS WILL CONTINUE SHIFTING SOUTHERLY CENTRAL AND EAST...WITH WESTERLIES WEST OF THE CONTDVD. SOUTH WINDS WILL ALSO BE BREEZY ACROSS THE NORTHEAST TOWARDS SUNSET THEN TAPERING OFF OVERNIGHT. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL FAVOR AREAS ALONG AND SOUTH OF THE I40 CORRIDOR...WITH CHANCES ALONG THE CENTRAL MOUNTAIN CHAIN THE REST OF THE AFTERNOON INTO THE EVENING HOURS. TEMPERATURES WERE BELOW NORMAL IN THE EAST...NEAR NORMAL WEST OF THE CENTRAL MOUNTAIN CHAIN. SHOWERS AND THICK CLOUD COVER SOUTH OF THE I40 CORRIDOR WILL GRADUALLY DIMINISH OVERNIGHT AS RECOVERIES IMPROVE GREATLY AREAWIDE THAN PREVIOUS. TEMPERATURES WILL REBOUND TO NEAR AND ABOVE NORMAL READINGS SUNDAY FOLLOWING A DOWN TREND IN MIN RH VALUES ACROSS THE NORTHERN HALF OF THE STATE AS DRIER MID LEVEL AIR FILTERS IN FROM THE NORTHWEST...WHILE RH VALUES REMAIN FAIR ACROSS THE FAR EAST AND SOUTHERN HALF OF THE STATE. ANY CHANCE OF SHOWERS WILL BE LIMITED TO SOUTHERN AREAS. OVERNIGHT RECOVERIES WILL DOWNTREND ACROSS PORTIONS OF THE NORTHWEST PLATEAU...ADJACENT HIGHLANDS AND THE SANGRE DE CRISTOS...WHILE REMAINING GOOD TO EXCELLENT ELSEWHERE. DOWN TREND IN RH VALUES WILL CONTINUE MONDAY ACROSS NORTHERN AREAS ...ESPECIALLY ACROSS THE NORTHWEST AS DRIER AIR REMAINS OVER THE NORTHERN HALF OF THE STATE. TEMPERATURES WILL BE NEAR NORMAL...ABOVE NORMAL IN THE EAST. ANY SHOWER CHANCES WILL BE LIMITED TO THE SOUTHWEST MOUNTAINS BECAUSE OF AN UPTREND IN MOISTURE LEVELS AHEAD OF AN APPROACHING UPPER LEVEL SYSTEM IN THE EASTERN PACIFIC. LATE MONDAY INTO TUESDAY...THE UPPER LEVEL LOW LOOKS TO CROSS OVER THE CALIFORNIA...NEVADA VALLEY USHERING THE MOISTURE BULLS EYE OVER ARIZONA...WITH SCATTERED CHANCES ACROSS WESTERN AND CENTRAL AREAS...BECOMING WIDESPREAD LATE TUESDAY INTO WEDNESDAY. RH VALUES AND RECOVERIES WILL GREATLY IMPROVE WEST TO EAST. BY THURSDAY...MODELS BEGAN TO DIFFER ON TIMING OF SHOWERS MOVING OUT OF THE STATE AS UPPER LEVEL RIDGING TAKES OVER TOWARD THE WEEKEND VENT RATES WILL IMPROVE CENTRAL AND NORTH SUNDAY...POOR ACROSS THE SOUTH CENTRAL MOUNTAINS...THEN BECOMING GOOD TO EXCELLENT IN THE EAST...FAIR IN THE SOUTH...TO POOR ACROSS PORTIONS OF THE NORTHWEST...SOUTH CENTRAL AND NORTH CENTRAL MOUNTAINS MONDAY...THEN IMPROVING AREA WIDE TUESDAY. && .AVIATION... 18Z TAF CYCLE AS THE BACK DOOR COLD FRONT CONTINUES PUSHING TOWARD THE SOUTHWEST MTNS FOLLOWING MID LEVEL MOISTURE FILTERING NORTHWARD FROM THE SOUTHERN BAJA PENINSULA...THICK CLOUD COVER/MVFR CIGS WILL CONTINUE TO FAVOR THE EAST CENTRAL AND SOUTHEAST PLAINS THROUGHOUT THE DAY...WITH PERIODS OF MVFR CIGS ALONG THE EAST SLOPES OF THE SANGRE DE CRISTOS. WINDS WILL CONTINUE SHIFTING SOUTH EASTERLY CENTRAL AND EAST AS POST BACK DOOR FRONTAL WINDS WASH OUT...WITH BREEZY SOUTHERLY WINDS ACROSS THE NORTHEAST. WINDS ACROSS WESTERN NM WILL SHIFT WESTERLY AFTER 20Z. HRRR MODELS ARE INDICATING SHRA/TSRA CHANCES FAVORING AREAS SOUTH OF THE INTERSTATE 40 CORRIDOR BUT ONLY ADDED VCSH FOR KROW. && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 45 86 42 86 / 5 0 0 0 DULCE........................... 33 79 28 81 / 10 0 0 0 CUBA............................ 46 77 44 78 / 10 0 0 5 GALLUP.......................... 41 85 37 85 / 5 0 0 5 EL MORRO........................ 39 78 36 78 / 10 0 0 10 GRANTS.......................... 41 82 37 82 / 10 5 0 5 QUEMADO......................... 52 79 49 77 / 20 10 0 20 GLENWOOD........................ 52 78 53 77 / 20 30 10 20 CHAMA........................... 42 73 32 74 / 10 0 0 5 LOS ALAMOS...................... 55 78 56 79 / 20 0 0 5 PECOS........................... 51 76 52 77 / 10 0 0 5 CERRO/QUESTA.................... 45 76 40 77 / 5 0 0 5 RED RIVER....................... 43 67 36 69 / 10 0 0 5 ANGEL FIRE...................... 49 68 44 69 / 10 0 0 5 TAOS............................ 42 80 40 82 / 5 0 0 5 MORA............................ 48 74 48 76 / 10 0 0 5 ESPANOLA........................ 49 85 47 85 / 10 0 0 0 SANTA FE........................ 53 79 54 79 / 10 0 0 5 SANTA FE AIRPORT................ 51 83 51 83 / 10 0 0 5 ALBUQUERQUE FOOTHILLS........... 60 84 60 84 / 10 5 0 5 ALBUQUERQUE HEIGHTS............. 60 86 61 86 / 10 0 0 0 ALBUQUERQUE VALLEY.............. 58 88 55 88 / 10 0 0 0 ALBUQUERQUE WEST MESA........... 58 87 59 87 / 10 0 0 0 LOS LUNAS....................... 54 89 52 89 / 10 0 0 5 RIO RANCHO...................... 57 87 58 87 / 10 0 0 0 SOCORRO......................... 59 88 60 90 / 10 5 5 5 SANDIA PARK/CEDAR CREST......... 54 80 52 81 / 20 5 0 5 TIJERAS......................... 56 82 46 83 / 20 5 0 5 MORIARTY/ESTANCIA............... 45 83 40 84 / 10 5 0 5 CLINES CORNERS.................. 52 79 52 81 / 10 5 0 5 GRAN QUIVIRA.................... 54 79 55 81 / 10 5 5 5 CARRIZOZO....................... 58 80 58 84 / 20 20 5 10 RUIDOSO......................... 53 72 54 76 / 20 30 10 20 CAPULIN......................... 50 77 51 81 / 10 0 0 5 RATON........................... 48 84 49 88 / 5 0 0 0 SPRINGER........................ 49 84 49 87 / 5 0 0 0 LAS VEGAS....................... 48 82 48 84 / 10 5 0 5 CLAYTON......................... 56 85 58 90 / 10 0 0 0 ROY............................. 53 83 53 85 / 10 5 0 0 CONCHAS......................... 60 89 60 91 / 10 5 0 0 SANTA ROSA...................... 60 88 60 89 / 10 5 0 0 TUCUMCARI....................... 60 90 61 93 / 10 5 0 0 CLOVIS.......................... 60 85 60 90 / 10 10 0 0 PORTALES........................ 62 84 62 89 / 10 10 0 0 FORT SUMNER..................... 62 86 62 89 / 5 5 0 0 ROSWELL......................... 63 88 61 93 / 10 10 0 0 PICACHO......................... 58 84 58 86 / 20 20 5 10 ELK............................. 56 73 56 78 / 20 30 10 10 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 33
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1146 AM MDT SAT SEP 19 2015 .AVIATION... 18Z TAF CYCLE AS THE BACK DOOR COLD FRONT CONTINUES PUSHING TOWARD THE SOUTHWEST MTNS FOLLOWING MID LEVEL MOISTURE FILTERING NORTHWARD FROM THE SOUTHERN BAJA PENINSULA...THICK CLOUD COVER/MVFR CIGS WILL CONTINUE TO FAVOR THE EAST CENTRAL AND SOUTHEAST PLAINS THROUGHOUT THE DAY...WITH PERIODS OF MVFR CIGS ALONG THE EAST SLOPES OF THE SANGRE DE CRISTOS. WINDS WILL CONTINUE SHIFTING SOUTH EASTERLY CENTRAL AND EAST AS POST BACK DOOR FRONTAL WINDS WASH OUT...WITH BREEZY SOUTHERLY WINDS ACROSS THE NORTHEAST. WINDS ACROSS WESTERN NM WILL SHIFT WESTERLY AFTER 20Z. HRRR MODELS ARE INDICATING SHRA/TSRA CHANCES FAVORING AREAS SOUTH OF THE INTERSTATE 40 CORRIDOR BUT ONLY ADDED VCSH FOR KROW. 32 && .PREV DISCUSSION...340 AM MDT SAT SEP 19 2015... .SYNOPSIS... A STRONG COLD FRONT SURGED THROUGH CENTRAL AND EASTERN NEW MEXICO AS OF EARLY SATURDAY. GUSTY NORTHEAST TO EAST WINDS ARE EXPECTED TO SLOWLY DIMINISH AS THE MORNING PROGRESSES. HIGHS IN THE EAST WILL FINALLY FALL TO BELOW AVERAGE TODAY...BUT WILL BE WITHIN A FEW DEGREES BOTH ABOVE AND BELOW NORMAL FOR THE CENTRAL AND WEST. BEST CHANCES FOR SHOWERS AND STORMS WILL BE SOUTH OF INTERSTATE 40 TODAY THROUGH SUNDAY...WITH HIGHS REBOUNDING SUNDAY. INCREASING MOISTURE IN ADVANCE OF AN UPPER LOW NEAR BAJA CALIFORNIA WILL BOOST CHANCES FOR SHOWERS AND STORMS MONDAY THROUGH WEDNESDAY BEFORE DRIER WEATHER DOMINATES LATE NEXT WEEK. && .DISCUSSION... FRONT MADE IT/S WAY THROUGH THE RGV AND APPEARS TO BE INVOF THE CONTDVD EARLY THIS MORNING. CONSIDERED DROPPING THE WIND ADVY FOR THE MIDDLE RGV...AS WINDS AT THE SUNPORT HAD DECREASED...WHILE ALLOWING THE REMAINDER OF THE ADVY TO CONTINUE UNTIL 7 AM...HOWEVER KABQ GUSTS HAVE INCREASED AGAIN...SO DECIDED TO LET THE ADVY CONTINUE IN IT/S ENTIRETY. OTHERWISE...THE FRONT LOOKED TO INITIATE AN ISOLD STORM IN THE LOWER RGV AROUND MIDNIGHT...WHICH DISSIPATED FAIRLY QUICKLY. ATTM ECHOES OBSERVED TO OUR SOUTH ASSOCIATED WITH DECAYING COMPLEX AS WELL AS FRONTAL BOUNDARY. FORECAST BEST MOISTURE AND INSTAB FOR TODAY LIKELY TO REMAIN SOUTH OF I-40 BUT THERE MAY BE ENOUGH MOISTURE AND INSTAB FOR AN ISOLD CELL OVER THE NRN MTS...SO LITTLE CHANGE FROM INHERITED GRIDS. HIGHS IN THE EAST FALL BELOW AVERAGE TODAY WHILE COOLER CENTRAL BUT STILL WITHIN A FEW DEGREES OF NORMAL. HIGHS REBOUND SUNDAY WITH BEST MOISTURE AND INSTAB FORECAST SOUTH OF I-40 AGAIN. GFS REMAINS SOMEWHAT FASTER THAN THE ECMWF OPENING UP THE UPPER LOW OFF BAJA AND BRINGING IT AS WELL AS A SLUG OF MOISTURE INTO NEW MEXICO...BUT THE IDEA IS THE SAME...MAINLY THE TIMING IS OFF. TUESDAY MAY SEE THE MOST WIDESPREAD SHOWERS AND STORMS WITH WETTING RAIN...WITH A DRY OUT FROM WEST TO EAST WEDNESDAY INTO THURSDAY. THERE MAY BE A WEAK SURFACE BOUNDARY IN THE EAST THURSDAY...BUT DOESN/T LOOK TO HAVE SIGNIFICANT IMPACT. UPPER HIGH DEVELOPS OVER THE STATE LATE IN THE WEEK...BUT POTENTIAL LATE NEXT WEEKEND FOR INCREASING WIND AND SHOWERS/STORMS WEST AND NORTH AS A STRONG TROUGH TRACKS THROUGH THE NRN/CENTRAL ROCKIES. && .FIRE WEATHER... BACK DOOR FRONT HAS POWERED ITS WAY THROUGH THE GAPS OF THE CENTRAL MOUNTAIN CHAIN AND IS CURRENTLY PUSHING TOWARD THE CONTINENTAL DIVIDE. GUSTY WINDS WILL CONTINUE BELOW CANYONS THROUGH SUNRISE OR SHORTLY THEREAFTER. LOW LEVEL MOISTURE BEHIND THE FRONT IS ALSO MAKING ITS WAY TOWARD THE CONTDVD. THIS COMBINED WITH SOME MID LEVEL MOISTURE CREEPING NORTHWARD SHOULD ALLOW FOR SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS THE WEST CENTRAL AND NORTHWEST HIGHLANDS THIS AFTERNOON AND EVENING. DESPITE THE INCREASE IN LOW LEVEL MOISTURE ACROSS THE PLAINS...TEMPERATURES WILL BE MUCH COOLER AND THEREFORE...CONDITIONS APPEAR TO BE TOO STABLE FOR MUCH...IF ANY...SHOWER DEVELOPMENT. MINIMUM HUMIDITIES THIS AFTERNOON WILL BE MUCH HIGHER THAN YESTERDAY FOR MOST AREAS...THOUGH WILL REMAIN BELOW 15 PERCENT ACROSS THE NORTHWEST PLATEAU. GOOD TO EXCELLENT RECOVERIES ARE EXPECTED TONIGHT. ON SUNDAY...DRY MID LEVEL AIR WILL NOSE BACK INTO THE NORTHERN HALF OR SO OF THE STATE...CONFINING SHOWERS AND THUNDERSTORMS TO THE SOUTHERN TIER OF THE FORECAST AREA...THOUGH WETTING RAINS WILL BE SPOTTY AT BEST. TEMPERATURES WILL REBOUND WHICH WILL RESULT IN DAYTIME HUMIDITIES TRENDING SHARPLY DOWNWARD. EARLY NEXT WEEK...MODELS CONTINUE TO BE AT ODDS REGARDING THE TIMING OF A SHORTWAVE TROUGH...OR TWO...AND THE ACCOMPANYING MOISTURE AND PRECIPITATION. IN GENERAL...MODELS AGREE THAN A WEAK SHORTWAVE WILL EJECT FROM THE MAIN LOW OVER THE PACIFIC AND MOVE NORTHEASTWARD OVER AZ AND NM SOMETIME BETWEEN MONDAY NIGHT AND TUESDAY. THEN...THE MAIN LOW WILL OPEN INTO A WAVE AND ALSO EJECT NORTHEASTWARD AROUND THE TUESDAY NIGHT INTO WEDNESDAY TIME FRAME. THE GFS TENDS TO BRING THE MAIN SLUG OF MOISTURE WITH THE INITIAL SHORTWAVE...WHILE THE ECMWF TENDS TO KEEP THAT MOISTURE LARGELY OVER AZ. HOWEVER...THE ECMWF DOES SHOW WIDESPREAD WETTING RAINS WITH THE MAIN TROUGH AS IT CROSSES NM. SINCE THESE DIFFERENCES HAVE BEEN PERSISTENT FOR MANY DAYS...BEST WE CAN SAY FOR NOW IS THAT MOISTURE AND PRECIPITATION CHANCES SHOULD BE TRENDING UPWARD FOR AT LEAST CENTRAL AND WESTERN NM EARLY NEXT WEEK. MANY AREAS SHOULD SEE WETTING RAINS...JUST A QUESTION OF TIMING. LOOKS LIKE BOTH MODELS REBUILD THE UPPER LEVEL HIGH OVER THE DESERT SOUTHWEST LATE NEXT WEEK WITH THUNDERSTORM CHANCES SIGNIFICANTLY REDUCED. POOR TO FAIR VENTILATION IS EXPECTED FOR MUCH OF THE RIO GRANDE VALLEY AND AREAS EASTWARD...WHILE SOME IMPROVEMENT IN VENT RATES WILL BE NOTED ACROSS THE WEST TODAY. WITH THE EXCEPTION OF POOR VENT RATES ACROSS THE LOWER RIO GRANDE VALLEY...VENT RATES ON SUNDAY SHOULD BE GOOD TO VERY GOOD AREAWIDE. THOUGH THE DETAILS ARE STILL BEING IRONED OUT FOR EARLY NEXT WEEK...IT CURRENTLY LOOKS LIKE POOR TO FAIR VENTILATION WILL PREVAIL ACROSS NORTHWEST AND NORTH CENTRAL AREAS MONDAY AND TUESDAY...WITH GOOD OR BETTER VENT RATES PREVAILING ELSEWHERE. && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS NORMAN OK
1007 PM CDT SUN SEP 20 2015 .UPDATE... DESPITE A COUPLE OF SHOWERS DEVELOPING /AND THEN DISSIPATING/ EARLIER THIS EVENING JUST NORTHWEST OF OKC... THE SHORT-TERM AND 00Z SYNOPTIC MODELS HAVE BACKED OFF ON THE REDEVELOPMENT OF SHOWERS LATER TONIGHT. WILL KEEP SOME LOW POPS... BUT LOWER THE POPS A BIT. ALSO THE DEVELOPMENT OF IFR STRATUS ACROSS PORTIONS OF THE AREA ALREADY MAKE IT LOOK LIKE IT MAY BE MORE OF A STRATUS NIGHT AS OPPOSED TO FOG. HRRR HAS ALSO BACKED OFF ON COVERAGE OF FOG. WILL CONTINUE TO MONITOR FOR ANY FOG DEVELOPMENT... BUT WILL REMOVE THE FOG FROM THE GRIDS FOR NOW. && .PREV DISCUSSION... /ISSUED 702 PM CDT SUN SEP 20 2015/ UPDATE... UPDATED THE GRIDS EARLY THIS EVENING TO ACCOUNT FOR CURRENT TRENDS IN PRECIP AND SHORT-TERM MODELS. THE PERSISTENT PRECIP SHIELD NOW ACROSS SOUTHEAST OKLAHOMA WILL CONTINUE TO MOVE SOUTHEAST. WENT WITH CATEGORICAL POPS FOR A COUPLE OF HOURS IN THE SOUTHEAST BEFORE DECREASING TO SLIGHT CHANCE/CHANCE CATEGORY. THE CONVECTION OVER THE TEXAS PANHANDLE IS DROPPING SOUTH-SOUTHEAST AND FOR THE MOST PART SHOULD STAY WEST OF THE 100TH MERIDIAN... BUT SOME DEVELOPMENT COULD BRUSH THE FAR SOUTHWESTERN PART OF THE AREA. SHORT-TERM MODELS SHOW SOME REDEVELOPMENT ACROSS NORTH CENTRAL/NORTHWEST OKLAHOMA LATER TONIGHT...LIKELY ASSOCIATED WITH A WEAK SHORTWAVE MOVING SOUTHEAST ACROSS THE PLAINS TONIGHT. ALSO ADDED MENTION OF PATCHY MORNING FOG. PREV DISCUSSION... /ISSUED 651 PM CDT SUN SEP 20 2015/ DISCUSSION... 21/00Z AVIATION DISCUSSION BELOW. AVIATION... IFR/MVFR CONDITIONS EXPECTED TO PERSIST ACROSS WESTERN AND NORTHERN OKLAHOMA TERMINALS FIRST HALF OF FORECAST PRIMARILY WITH CIGS BUT AREAS OF SHALLOW FOG ALSO POSSIBLE IN AREAS THAT SAW APPRECIABLE RAINFALL AMOUNTS TODAY. IF WE HAVE AREAS OF DENSE FOG IT IS MOST LIKELY ACROSS NORTH-CENTRAL OKLAHOMA NORTH OF WARM FRONT. LIFT ASSOCIATED WITH KS S/WV TONIGHT MAY YIELD SCATTERED RA/TSRA MAINLY OVER NORTHERN OKLAHOMA. CLEARING WITH RETURN TO SOUTHERLY WINDS REGIONWIDE AFTER 15Z TOMORROW. PREV DISCUSSION... /ISSUED 155 PM CDT SUN SEP 20 2015/ DISCUSSION... THE LARGE AREA OF LIGHT RAIN OVER CENTRAL AND SOUTH CENTRAL OKLAHOMA IS EXPECTED TO CONTINUE ITS SLOW EASTWARD MOVEMENT AND BE MOSTLY EAST OF OKLAHOMA CITY BY LATE AFTERNOON. A FEW AREAS COULD RECEIVE MINOR FLOODING FROM THE SLOW MOVEMENT. CLOUDS WILL HOLD OVER THIS AREA INTO THE EVENING. IN SUNNIER AREAS OF WESTERN OKLAHOMA LATE THIS AFTERNOON, STABILITY MAY LOWER SUFFICIENTLY TO SUPPORT ISOLATED THUNDERSTORMS THIS EVENING WHICH MAY MOVE EAST FROM TEXAS. THESE WOULD BE SHORT- LIVED AND LARGELY DRIVEN BY DAYTIME INSTABILITY. APART FROM THAT, EARLY MONDAY A WEAK WAVE IS EXPECTED TO QUICKLY PASS TO THE NORTHEAST OF OKLAHOMA BUT BRING A SMALL CHANCE FOR THUNDERSTORMS MONDAY MORNING. AFTER THAT, A QUICK WARM UP TO RETURN TO HOT WEATHER WILL START. MOST OF THE WEEK WILL SEE TEMPERATURES 5 TO 10 DEGREES ABOVE LATE SEPTEMBER NORMALS WHEN THE LONG-PERSISTENT UPPER RIDGE BUILDS AGAIN OVER OKLAHOMA AND TEXAS. THERE IS A SLIGHT CHANCE FOR RAIN IN NORTHERN OKLAHOMA THURSDAY WHEN WEAK INFLUENCE FROM A WESTERLY WAVE PASSES QUICKLY; OTHERWISE, THE HOT AIRMASS WILL DOMINATE IN THE PRESENCES OF THE UPPER HIGH PRESSURE. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 65 87 67 90 / 20 10 0 0 HOBART OK 65 91 68 93 / 20 0 0 0 WICHITA FALLS TX 67 93 69 94 / 30 0 0 0 GAGE OK 64 92 67 92 / 20 0 0 0 PONCA CITY OK 64 86 67 89 / 20 20 0 0 DURANT OK 66 90 68 92 / 70 10 0 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 99/99
AREA FORECAST DISCUSSION
NWS NORMAN OK
107 PM CDT SAT SEP 19 2015 .DISCUSSION... && .AVIATION... CEILINGS WILL LOWER OVERNIGHT WHEN LIFT OVER THE COLD FRONT WILL HELP GENERATE SHOWERS AND A FEW THUNDERSTORMS OVER THE SOUTHERN OR CENTRAL THIRD OF OKLAHOMA. MVFR CEILINGS ARE EXPECTED BY SUNRISE SUNDAY IN MUCH OF THIS AREA. THUNDER IS LESS LIKELY THROUGH THE MORNING, BUT RAIN AND LOW CEILINGS WILL LIKELY CONTINUE. && .PREV DISCUSSION... /ISSUED 1140 AM CDT SAT SEP 19 2015/ UPDATE... ADJUSTED PRECIP/WX... TEMPS... DISCUSSION... BROKEN AREA OF SHOWERS CONTINUES TO SLOWLY DISSIPATE AND MOVE SOUTHWARD OUT OF SOUTH CENTRAL OK INTO NRN TX THIS MORNING. REMOVED CHANCES ACROSS CENTRAL AND SWRN OK AND WRN N TX GIVEN CURRENT RADAR TRENDS AND MORE STABLE AIRMASS BUILDING INTO THE REGION AS THE SFC FRONT HAS PUSHED WELL SOUTH OF THE RED RIVER. BROUGHT BACK A 15 TO 20 PERCENT CHANCE OF ISOLATED SHOWER DEVELOPMENT IN SWRN OK/WRN N TX THROUGH THE AFTN... AS THE RIDGE CENTERED OVER WEST TX COMES INTO PLAY... WITH MODEST MOISTURE CONTINUE TO TRAVERSE THE CAPROCK INTO THE TX PANHANDLE AND WRN OK. WV IMAGERY SHOWS THIS FEATURE QUITE WELL. IN RESPONSE... THERE IS A SLIGHT SIGNAL OF ISENTROPIC ASCENT FROM THE TX PANHANDLE INTO THE RED RIVER VALLEY OF SWRN OK/WRN N TX THROUGH 00Z (0700 PM CDT). HOWEVER... GIVEN 4000 TO 5000 FT CLOUD BASES AND 20 TO 25 DEGREES SFC TEMP/DPT SPREADS... SHOWERS WILL BE FAR AND FEW BETWEEN IF ANYTHING DEVELOPS THIS AFTN. THE VAST MAJORITY WILL STAY DRY. JTK PREV DISCUSSION... /ISSUED 657 AM CDT SAT SEP 19 2015/ DISCUSSION... PLEASE SEE THE 12Z AVIATION DISCUSSION BELOW. AVIATION... BRIEF MVFR CIGS ARE EXPECTED THIS MORNING AT A FEW OF THE TERMINALS...BUT CONDITIONS WILL IMPROVE TO VFR AROUND 14-16Z. ALL OF THE SHOWERS/STORMS HAVE MOVED INTO SE OK THIS MORNING SO DO NOT EXPECT ANY PRECIP OVER THE TERMINALS FOR THE NEXT 12 HOURS. MID TO HIGH CLOUDS WILL REMAIN OVERHEAD THROUGH MOST OF THE DAY. EXPECT NORTH WINDS THROUGH THE AFTERNOON...SHIFTING TO THE ENE THIS EVENING. PREV DISCUSSION... /ISSUED 313 AM CDT SAT SEP 19 2015/ DISCUSSION... SCATTERED SHOWERS AND THUNDERSTORMS WILL SLOWLY CONTINUE TO SLIDE SOUTH WITH THE 850 MB FRONTOGENETIC ZONE THROUGH THE MORNING HOURS. THE HRRR HAS THE BEST HANDLE ON WHAT IS OCCURRING RIGHT NOW SO POPS WERE ADJUSTED UPWARD ALONG THIS NARROW ZONE THROUGH SUNRISE. MOST OF THE RAIN WILL MOVE TOWARD THE RED RIVER BEFORE LUNCHTIME AND SKIES WILL CONTINUE TO CLEAR FROM NE TO SW. EXPECT LINGERING STRATUS ACROSS THE SW...HOWEVER...THROUGH MOST OF THE DAY. MUCH COOLER TEMPS ARE EXPECTED TODAY BEHIND THE COLD FRONT FROM THE MID 70S NORTHWARD TO THE LOW 80S SOUTHWARD. THE NEXT CHANCE FOR RAIN RETURNS SUN AS ISENTROPIC ASCENT DEVELOPS AND A WEAK MID LEVEL SHORTWAVE TROUGH MOVES OUT OF THE ROCKIES. THE HIGHEST CHANCES WILL LIKELY BE DURING THE MORNING HOURS ACROSS WESTERN AND CENTRAL OK...AND THEN SHIFT NE/E DURING THE DAY. DECIDED TO LOWER TEMPS ACROSS THE NORTH AND EAST FOR THIS REASON SIMILAR TO THE NAM12. RAIN CHANCES WILL LINGER ACROSS THE EAST THROUGH EARLY MON AM AS A MORE SIGNIFICANT MID TO UPPER LEVEL SHORTWAVE TROUGH MOVES INTO NE/E OK. MONDAY SHOULD BE MOSTLY CLEAR AS THE WAVE QUICKLY MOVES INTO THE MISS RIVER VALLEY. TEMPS WILL BEGIN TO REBOUND BACK TO/OR JUST ABOVE AVG MONDAY...AND THEN WARM UP THROUGH MID WEEK AS THE SUBTROPICAL RIDGE MOVES OVER THE SOUTHERN PLAINS. MOST OF THE NWP MODELS INDICATE A MID TO UPPER SHORTWAVE TROUGH WILL MOVE SOMEWHERE NEAR KS THROUGH THURS SO WILL GO WITH SOME SLIGHT CHCS ACROSS NORTHERN OK DURING THIS TIME PERIOD. OTHERWISE...EXPECT ABOVE AVG TEMPS THROUGH THE EXTENDED PERIOD. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 61 81 64 87 / 60 60 30 10 HOBART OK 62 85 65 91 / 60 50 20 0 WICHITA FALLS TX 66 88 67 92 / 60 50 20 0 GAGE OK 58 84 62 90 / 30 40 10 0 PONCA CITY OK 57 76 62 84 / 20 30 30 10 DURANT OK 67 86 66 89 / 40 50 30 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 03/09/09
AREA FORECAST DISCUSSION
NWS NORMAN OK
1140 AM CDT SAT SEP 19 2015 .UPDATE... ADJUSTED PRECIP/WX... TEMPS... && .DISCUSSION... BROKEN AREA OF SHOWERS CONTINUES TO SLOWLY DISSIPATE AND MOVE SOUTHWARD OUT OF SOUTH CENTRAL OK INTO NRN TX THIS MORNING. REMOVED CHANCES ACROSS CENTRAL AND SWRN OK AND WRN N TX GIVEN CURRENT RADAR TRENDS AND MORE STABLE AIRMASS BUILDING INTO THE REGION AS THE SFC FRONT HAS PUSHED WELL SOUTH OF THE RED RIVER. BROUGHT BACK A 15 TO 20 PERCENT CHANCE OF ISOLATED SHOWER DEVELOPMENT IN SWRN OK/WRN N TX THROUGH THE AFTN... AS THE RIDGE CENTERED OVER WEST TX COMES INTO PLAY... WITH MODEST MOISTURE CONTINUE TO TRAVERSE THE CAPROCK INTO THE TX PANHANDLE AND WRN OK. WV IMAGERY SHOWS THIS FEATURE QUITE WELL. IN RESPONSE... THERE IS A SLIGHT SIGNAL OF ISENTROPIC ASCENT FROM THE TX PANHANDLE INTO THE RED RIVER VALLEY OF SWRN OK/WRN N TX THROUGH 00Z (0700 PM CDT). HOWEVER... GIVEN 4000 TO 5000 FT CLOUD BASES AND 20 TO 25 DEGREES SFC TEMP/DPT SPREADS... SHOWERS WILL BE FAR AND FEW BETWEEN IF ANYTHING DEVELOPS THIS AFTN. THE VAST MAJORITY WILL STAY DRY. JTK && .PREV DISCUSSION... /ISSUED 657 AM CDT SAT SEP 19 2015/ DISCUSSION... PLEASE SEE THE 12Z AVIATION DISCUSSION BELOW. AVIATION... BRIEF MVFR CIGS ARE EXPECTED THIS MORNING AT A FEW OF THE TERMINALS...BUT CONDITIONS WILL IMPROVE TO VFR AROUND 14-16Z. ALL OF THE SHOWERS/STORMS HAVE MOVED INTO SE OK THIS MORNING SO DO NOT EXPECT ANY PRECIP OVER THE TERMINALS FOR THE NEXT 12 HOURS. MID TO HIGH CLOUDS WILL REMAIN OVERHEAD THROUGH MOST OF THE DAY. EXPECT NORTH WINDS THROUGH THE AFTERNOON...SHIFTING TO THE ENE THIS EVENING. PREV DISCUSSION... /ISSUED 313 AM CDT SAT SEP 19 2015/ DISCUSSION... SCATTERED SHOWERS AND THUNDERSTORMS WILL SLOWLY CONTINUE TO SLIDE SOUTH WITH THE 850 MB FRONTOGENETIC ZONE THROUGH THE MORNING HOURS. THE HRRR HAS THE BEST HANDLE ON WHAT IS OCCURRING RIGHT NOW SO POPS WERE ADJUSTED UPWARD ALONG THIS NARROW ZONE THROUGH SUNRISE. MOST OF THE RAIN WILL MOVE TOWARD THE RED RIVER BEFORE LUNCHTIME AND SKIES WILL CONTINUE TO CLEAR FROM NE TO SW. EXPECT LINGERING STRATUS ACROSS THE SW...HOWEVER...THROUGH MOST OF THE DAY. MUCH COOLER TEMPS ARE EXPECTED TODAY BEHIND THE COLD FRONT FROM THE MID 70S NORTHWARD TO THE LOW 80S SOUTHWARD. THE NEXT CHANCE FOR RAIN RETURNS SUN AS ISENTROPIC ASCENT DEVELOPS AND A WEAK MID LEVEL SHORTWAVE TROUGH MOVES OUT OF THE ROCKIES. THE HIGHEST CHANCES WILL LIKELY BE DURING THE MORNING HOURS ACROSS WESTERN AND CENTRAL OK...AND THEN SHIFT NE/E DURING THE DAY. DECIDED TO LOWER TEMPS ACROSS THE NORTH AND EAST FOR THIS REASON SIMILAR TO THE NAM12. RAIN CHANCES WILL LINGER ACROSS THE EAST THROUGH EARLY MON AM AS A MORE SIGNIFICANT MID TO UPPER LEVEL SHORTWAVE TROUGH MOVES INTO NE/E OK. MONDAY SHOULD BE MOSTLY CLEAR AS THE WAVE QUICKLY MOVES INTO THE MISS RIVER VALLEY. TEMPS WILL BEGIN TO REBOUND BACK TO/OR JUST ABOVE AVG MONDAY...AND THEN WARM UP THROUGH MID WEEK AS THE SUBTROPICAL RIDGE MOVES OVER THE SOUTHERN PLAINS. MOST OF THE NWP MODELS INDICATE A MID TO UPPER SHORTWAVE TROUGH WILL MOVE SOMEWHERE NEAR KS THROUGH THURS SO WILL GO WITH SOME SLIGHT CHCS ACROSS NORTHERN OK DURING THIS TIME PERIOD. OTHERWISE...EXPECT ABOVE AVG TEMPS THROUGH THE EXTENDED PERIOD. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 77 61 81 64 / 20 40 50 30 HOBART OK 77 62 85 65 / 20 50 50 20 WICHITA FALLS TX 79 66 88 67 / 40 40 40 20 GAGE OK 76 58 84 62 / 10 30 40 10 PONCA CITY OK 77 57 76 62 / 10 20 30 30 DURANT OK 83 67 86 66 / 30 40 50 30 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$
AREA FORECAST DISCUSSION
NWS NORMAN OK
657 AM CDT SAT SEP 19 2015 .DISCUSSION... PLEASE SEE THE 12Z AVIATION DISCUSSION BELOW. && .AVIATION... BRIEF MVFR CIGS ARE EXPECTED THIS MORNING AT A FEW OF THE TERMINALS...BUT CONDITIONS WILL IMPROVE TO VFR AROUND 14-16Z. ALL OF THE SHOWERS/STORMS HAVE MOVED INTO SE OK THIS MORNING SO DO NOT EXPECT ANY PRECIP OVER THE TERMINALS FOR THE NEXT 12 HOURS. MID TO HIGH CLOUDS WILL REMAIN OVERHEAD THROUGH MOST OF THE DAY. EXPECT NORTH WINDS THROUGH THE AFTERNOON...SHIFTING TO THE ENE THIS EVENING. && .PREV DISCUSSION... /ISSUED 313 AM CDT SAT SEP 19 2015/ DISCUSSION... SCATTERED SHOWERS AND THUNDERSTORMS WILL SLOWLY CONTINUE TO SLIDE SOUTH WITH THE 850 MB FRONTOGENETIC ZONE THROUGH THE MORNING HOURS. THE HRRR HAS THE BEST HANDLE ON WHAT IS OCCURRING RIGHT NOW SO POPS WERE ADJUSTED UPWARD ALONG THIS NARROW ZONE THROUGH SUNRISE. MOST OF THE RAIN WILL MOVE TOWARD THE RED RIVER BEFORE LUNCHTIME AND SKIES WILL CONTINUE TO CLEAR FROM NE TO SW. EXPECT LINGERING STRATUS ACROSS THE SW...HOWEVER...THROUGH MOST OF THE DAY. MUCH COOLER TEMPS ARE EXPECTED TODAY BEHIND THE COLD FRONT FROM THE MID 70S NORTHWARD TO THE LOW 80S SOUTHWARD. THE NEXT CHANCE FOR RAIN RETURNS SUN AS ISENTROPIC ASCENT DEVELOPS AND A WEAK MID LEVEL SHORTWAVE TROUGH MOVES OUT OF THE ROCKIES. THE HIGHEST CHANCES WILL LIKELY BE DURING THE MORNING HOURS ACROSS WESTERN AND CENTRAL OK...AND THEN SHIFT NE/E DURING THE DAY. DECIDED TO LOWER TEMPS ACROSS THE NORTH AND EAST FOR THIS REASON SIMILAR TO THE NAM12. RAIN CHANCES WILL LINGER ACROSS THE EAST THROUGH EARLY MON AM AS A MORE SIGNIFICANT MID TO UPPER LEVEL SHORTWAVE TROUGH MOVES INTO NE/E OK. MONDAY SHOULD BE MOSTLY CLEAR AS THE WAVE QUICKLY MOVES INTO THE MISS RIVER VALLEY. TEMPS WILL BEGIN TO REBOUND BACK TO/OR JUST ABOVE AVG MONDAY...AND THEN WARM UP THROUGH MID WEEK AS THE SUBTROPICAL RIDGE MOVES OVER THE SOUTHERN PLAINS. MOST OF THE NWP MODELS INDICATE A MID TO UPPER SHORTWAVE TROUGH WILL MOVE SOMEWHERE NEAR KS THROUGH THURS SO WILL GO WITH SOME SLIGHT CHCS ACROSS NORTHERN OK DURING THIS TIME PERIOD. OTHERWISE...EXPECT ABOVE AVG TEMPS THROUGH THE EXTENDED PERIOD. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 76 61 81 64 / 20 40 50 30 HOBART OK 77 62 85 65 / 20 50 50 20 WICHITA FALLS TX 82 66 88 67 / 40 40 40 20 GAGE OK 76 58 84 62 / 10 30 40 10 PONCA CITY OK 77 57 76 62 / 10 20 30 30 DURANT OK 84 67 86 66 / 30 40 50 30 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 26/03/03
AREA FORECAST DISCUSSION
NWS NORMAN OK
313 AM CDT SAT SEP 19 2015 .DISCUSSION... SCATTERED SHOWERS AND THUNDERSTORMS WILL SLOWLY CONTINUE TO SLIDE SOUTH WITH THE 850 MB FRONTOGENETIC ZONE THROUGH THE MORNING HOURS. THE HRRR HAS THE BEST HANDLE ON WHAT IS OCCURRING RIGHT NOW SO POPS WERE ADJUSTED UPWARD ALONG THIS NARROW ZONE THROUGH SUNRISE. MOST OF THE RAIN WILL MOVE TOWARD THE RED RIVER BEFORE LUNCHTIME AND SKIES WILL CONTINUE TO CLEAR FROM NE TO SW. EXPECT LINGERING STRATUS ACROSS THE SW...HOWEVER...THROUGH MOST OF THE DAY. MUCH COOLER TEMPS ARE EXPECTED TODAY BEHIND THE COLD FRONT FROM THE MID 70S NORTHWARD TO THE LOW 80S SOUTHWARD. THE NEXT CHANCE FOR RAIN RETURNS SUN AS ISENTROPIC ASCENT DEVELOPS AND A WEAK MID LEVEL SHORTWAVE TROUGH MOVES OUT OF THE ROCKIES. THE HIGHEST CHANCES WILL LIKELY BE DURING THE MORNING HOURS ACROSS WESTERN AND CENTRAL OK...AND THEN SHIFT NE/E DURING THE DAY. DECIDED TO LOWER TEMPS ACROSS THE NORTH AND EAST FOR THIS REASON SIMILAR TO THE NAM12. RAIN CHANCES WILL LINGER ACROSS THE EAST THROUGH EARLY MON AM AS A MORE SIGNIFICANT MID TO UPPER LEVEL SHORTWAVE TROUGH MOVES INTO NE/E OK. MONDAY SHOULD BE MOSTLY CLEAR AS THE WAVE QUICKLY MOVES INTO THE MISS RIVER VALLEY. TEMPS WILL BEGIN TO REBOUND BACK TO/OR JUST ABOVE AVG MONDAY...AND THEN WARM UP THROUGH MID WEEK AS THE SUBTROPICAL RIDGE MOVES OVER THE SOUTHERN PLAINS. MOST OF THE NWP MODELS INDICATE A MID TO UPPER SHORTWAVE TROUGH WILL MOVE SOMEWHERE NEAR KS THROUGH THURS SO WILL GO WITH SOME SLIGHT CHCS ACROSS NORTHERN OK DURING THIS TIME PERIOD. OTHERWISE...EXPECT ABOVE AVG TEMPS THROUGH THE EXTENDED PERIOD. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 76 61 81 64 / 20 40 40 30 HOBART OK 77 62 85 65 / 20 50 50 20 WICHITA FALLS TX 82 66 88 67 / 40 40 40 20 GAGE OK 76 58 84 62 / 10 30 40 10 PONCA CITY OK 77 57 76 62 / 10 20 30 30 DURANT OK 84 67 86 66 / 30 40 50 30 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 26/03
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
555 PM EDT SAT SEP 19 2015 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE AREA TODAY. HIGH PRESSURE WILL BRING A RETURN OF NEAR NORMAL DAYTIME TEMPERATURES FOR SUNDAY AND CONTINUE INTO THE MIDDLE OF NEXT WEEK. AN UPPER LEVEL LOW MAY LEAD TO A FEW SHOWERS MONDAY OR TUESDAY OVER THE SOUTHERN MOUNTAINS. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... EARLY THIS AFTERNOON...SURFACE LOW LIFTING OUT OF EASTERN GREAT LAKES WITH TRAILING COLD FRONT PROGRESSING ACROSS OHIO VALLEY /AT 17Z MOVING INTO CENTRAL OH/. THERE IS GOOD AGREEMENT ON THE TIMING OF THE FRONT...ENTERING WESTERN PA SHORTLY AFTER 18Z...AND MOVING INTO THE SUSQ VALLEY AROUND 03Z SUN. CONVECTION ALONG THE COLD FRONT WILL ORGANIZE TO OUR WEST AND ENTER THE NWRN MOUNTAINS DURING THE MID AFTERNOON. TOUGH TO FIND MUCH CAPE FURTHER EAST...SO SHOULD SEE A DEF WEAKENING TREND TO PRECIP AS FRONT SLIDES INTO THE ALLEGHENY FRONT AND CENTRAL MTNS. INTERESTING FEATURE FIRST HINTED AT BY THE LAST COUPLE RUNS OF THE HRRR /AND LIKELY WELL OVERDONE BY HRRR/ AND ON DISPLAY IN THE WV IS A VERY SUBTLE SHORTWAVE SLIDING FROM THE SOUTHERN TIP OF ILLINOIS AT 10Z TO SE OHIO AT 17Z BEGINNING TO SHOW SOME ENHANCED CLOUD HEIGHTS IN A NARROW DEFORMATION ZONE. THIS FEATURE WILL SLIDE NE IN QUICK MID-LEVEL FLOW OVER NEXT SEVERAL HOURS AND SHOULD BE ENOUGH TO KICK START SOME TSTMS OVER W PA WHERE CAPES ARE ONLY AROUND 500J/KG. IT REMAINS A BIT UNCLEAR JUST HOW FAR EAST OF A LINE FROM ABOUT BEDFORD TO STATE COLLEGE TO WILLIAMSPORT THE RAIN WILL MANAGE TO GET BEFORE PETERING OUT THOUGH...SO HELD ONTO SCT POPS THERE...RAMPING POPS HIGHER HEADING INTO NW MTNS. DID HOLD TSTM PROBS IN THE SCT CATEGORY...WITH FAST FLOW NOT TOTALLY RULING OUT AN ISOLATED STRONGER WIND GUST THERE /AS NOTED IN THE SPC DAY1 DISCUSSION CONCERNING A MARGINAL RISK/. WE`LL EEK OUT ONE MORE WARM DAY AHEAD OF THE COLD FRONT WITH HIGHS IN THE MID 70S TO MID 80S MOST LOCALES...WITH A SSW BREEZE OVER WESTERN SECTIONS. A COOL DOWN WILL BEGIN TONIGHT AS HIGH PRESSURE PUSHES QUICKLY INTO THE EASTERN GR LAKES AND SHOVES THE COLD FRONT OFF TO THE SOUTH. LOWS WILL RANGE FROM THE CHILLY MID 40S OVER THE NORTH TO AROUND 60 IN THE SOUTHEAST. OVER AREAS WHERE SKIES CLEAR TONIGHT...FOG SEEMS LIKELY LATE. THE BEST CHANCE WOULD SEEM TO BE OVER THE NORTHERN MOUNTAINS. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... CLOUDS WILL SETTLE OFF TO THE SOUTH SUNDAY AS HIGH PRESSURE QUICKLY MOVES INTO NORTHERN PA/SOUTHERN NY. IT WILL BE A MARKEDLY COOLER DAY WITH HIGHS AVERAGING AROUND 10 DEG COOLER THAN TODAY. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... PATCHY FROST IS POSSIBLE OVER THE NORTHWEST VALLEYS AS TEMPERATURES DROP INTO THE MID 30S BY MONDAY MORNING. TEMPERATURES WILL MODERATE AFTER THAT AS AN UPPER TROUGH DRIFTS TOWARD PENNSYLVANIA FROM THE MIDWEST. INCREASING CLOUDS AHEAD OF THIS SYSTEM WILL THEN LEAD TO ISOLATED SHOWERS LATE MONDAY INTO TUESDAY. THE SLOW MOVING UPPER TROUGH DIGS INTO THE SOUTHEAST STATES...ULTIMATELY CLOSING OFF NEAR THE CAROLINA COAST. UNCERTAINTY IN THE FORECAST INCREASES IN THIS PERIOD AS THE SYSTEM MAY STILL BE CLOSE ENOUGH TO THE AREA TO BRING AN EASTERLY WIND AND LOW CLOUD/SHOWER CHANCES. KEPT THINGS DRY FOR THIS TIME THOUGH BUT WILL HAVE TO ADJUST AS THE TRACK OF THE UPPER TROUGH/LOW COMES INTO FOCUS THROUGH EARLY WEEK. && .AVIATION /22Z SATURDAY THROUGH THURSDAY/... REGIONAL RADAR AT 21Z SHOWS A LINE OF SHRA/TSRA ALONG COLD FRONT MOVING INTO WESTERN PA. FROPA IS LIKELY TO BE ACCOMPANIED BY A A BRIEF TSRA AND A WIND SHIFT FROM SW TO NW AT KBFD ARND 23Z. UPSTREAM REPORTS AT KERI AND KWBC SHOWING A SCT LYR AT 700FT IMMEDIATELY BEHIND FRONT. FEEL A BRIEF DIP TO IFR CIGS AT KBFD IS QUITE POSSIBLE BTWN 23Z-01Z AS POST-FRONTAL MOISTURE IS FORCED OVER THE HIGH TERRAIN SURROUNDING KBFD. DRIER AIR WILL WORK IN ON NW FLOW LATER TONIGHT...LIKELY RESULTING IN A MORE FAVORABLE /MVFR/ STRATOCU DECK OVERNIGHT. ELSEWHERE...EXPECT SHOWERS TO DWINDLE AS WEAKENING FRONT MOVES SE INTO THE REST OF THE AREA LATE THIS EVENING. LATEST NEAR TERM MDLS SUGGEST THE DWINDLING LINE OF SHOWERS WILL MAKE IT TO KIPT/KUNV/KAOO/KJST AS FRONT MOVES THRU ARND 03Z. FURTHER SE...THE FRONT SHOULD COME THRU DRY ARND 07Z AT KMDT/KLNS. A PERIOD OF MVFR CIGS IS LIKELY AT KUNV/KAOO BTWN 03Z-06Z BEFORE DRIER NW FLOW BRINGS IMPROVEMENT LATE TONIGHT. AT KJST...UPSLOPE FLOW COULD MAINTAIN MVFR CIGS THRU DAWN. FURTHER SE...MDL SOUNDINGS SUGGEST VFR CONDS ARE LIKELY TO LAST THRU THE ENTIRE NIGHT AT KIPT/KMDT/KLNS. HIGH PRES AND DRY AIR MASS WILL BUILD IN FROM THE GRT LKS ON SUNDAY...BRINGING A NEAR CERTAINTY OF WIDESPREAD VFR CONDS. PRES GRADIENT BTWN HIGH PRES TO THE WEST AND LOW PRES OFF THE E COAST...WILL CREATE SOME FAIRLY GUSTY NORTH WINDS SUNDAY...ESP ACROSS EASTERN PA...WHERE BUFKIT SOUNDINGS INDICATE GUSTS NR 20KTS. OUTLOOK... SUN-WED...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE/RXR NEAR TERM...LA CORTE/RXR SHORT TERM...LA CORTE LONG TERM...LA CORTE/TYBURSKI AVIATION...FITZGERALD/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
339 PM EDT SAT SEP 19 2015 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE AREA TODAY. HIGH PRESSURE WILL BRING A RETURN OF NEAR NORMAL DAYTIME TEMPERATURES FOR SUNDAY AND CONTINUE INTO THE MIDDLE OF NEXT WEEK. AN UPPER LEVEL LOW MAY LEAD TO A FEW SHOWERS MONDAY OR TUESDAY OVER THE SOUTHERN MOUNTAINS. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... EARLY THIS AFTERNOON...SURFACE LOW LIFTING OUT OF EASTERN GREAT LAKES WITH TRAILING COLD FRONT PROGRESSING ACROSS OHIO VALLEY /AT 17Z MOVING INTO CENTRAL OH/. THERE IS GOOD AGREEMENT ON THE TIMING OF THE FRONT...ENTERING WESTERN PA SHORTLY AFTER 18Z...AND MOVING INTO THE SUSQ VALLEY AROUND 03Z SUN. CONVECTION ALONG THE COLD FRONT WILL ORGANIZE TO OUR WEST AND ENTER THE NWRN MOUNTAINS DURING THE MID AFTERNOON. TOUGH TO FIND MUCH CAPE FURTHER EAST...SO SHOULD SEE A DEF WEAKENING TREND TO PRECIP AS FRONT SLIDES INTO THE ALLEGHENY FRONT AND CENTRAL MTNS. INTERESTING FEATURE FIRST HINTED AT BY THE LAST COUPLE RUNS OF THE HRRR /AND LIKELY WELL OVERDONE BY HRRR/ AND ON DISPLAY IN THE WV IS A VERY SUBTLE SHORTWAVE SLIDING FROM THE SOUTHERN TIP OF ILLINOIS AT 10Z TO SE OHIO AT 17Z BEGINNING TO SHOW SOME ENHANCED CLOUD HEIGHTS IN A NARROW DEFORMATION ZONE. THIS FEATURE WILL SLIDE NE IN QUICK MID-LEVEL FLOW OVER NEXT SEVERAL HOURS AND SHOULD BE ENOUGH TO KICK START SOME TSTMS OVER W PA WHERE CAPES ARE ONLY AROUND 500J/KG. IT REMAINS A BIT UNCLEAR JUST HOW FAR EAST OF A LINE FROM ABOUT BEDFORD TO STATE COLLEGE TO WILLIAMSPORT THE RAIN WILL MANAGE TO GET BEFORE PETERING OUT THOUGH...SO HELD ONTO SCT POPS THERE...RAMPING POPS HIGHER HEADING INTO NW MTNS. DID HOLD TSTM PROBS IN THE SCT CATEGORY...WITH FAST FLOW NOT TOTALLY RULING OUT AN ISOLATED STRONGER WIND GUST THERE /AS NOTED IN THE SPC DAY1 DISCUSSION CONCERNING A MARGINAL RISK/. WE`LL EEK OUT ONE MORE WARM DAY AHEAD OF THE COLD FRONT WITH HIGHS IN THE MID 70S TO MID 80S MOST LOCALES...WITH A SSW BREEZE OVER WESTERN SECTIONS. A COOL DOWN WILL BEGIN TONIGHT AS HIGH PRESSURE PUSHES QUICKLY INTO THE EASTERN GR LAKES AND SHOVES THE COLD FRONT OFF TO THE SOUTH. LOWS WILL RANGE FROM THE CHILLY MID 40S OVER THE NORTH TO AROUND 60 IN THE SOUTHEAST. OVER AREAS WHERE SKIES CLEAR TONIGHT...FOG SEEMS LIKELY LATE. THE BEST CHANCE WOULD SEEM TO BE OVER THE NORTHERN MOUNTAINS. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... CLOUDS WILL SETTLE OFF TO THE SOUTH SUNDAY AS HIGH PRESSURE QUICKLY MOVES INTO NORTHERN PA/SOUTHERN NY. IT WILL BE A MARKEDLY COOLER DAY WITH HIGHS AVERAGING AROUND 10 DEG COOLER THAN TODAY. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... PATCHY FROST IS POSSIBLE OVER THE NORTHWEST VALLEYS AS TEMPERATURES DROP INTO THE MID 30S BY MONDAY MORNING. TEMPERATURES WILL MODERATE AFTER THAT AS AN UPPER TROUGH DRIFTS TOWARD PENNSYLVANIA FROM THE MIDWEST. INCREASING CLOUDS AHEAD OF THIS SYSTEM WILL THEN LEAD TO ISOLATED SHOWERS LATE MONDAY INTO TUESDAY. THE SLOW MOVING UPPER TROUGH DIGS INTO THE SOUTHEAST STATES...ULTIMATELY CLOSING OFF NEAR THE CAROLINA COAST. UNCERTAINTY IN THE FORECAST INCREASES IN THIS PERIOD AS THE SYSTEM MAY STILL BE CLOSE ENOUGH TO THE AREA TO BRING AN EASTERLY WIND AND LOW CLOUD/SHOWER CHANCES. KEPT THINGS DRY FOR THIS TIME THOUGH BUT WILL HAVE TO ADJUST AS THE TRACK OF THE UPPER TROUGH/LOW COMES INTO FOCUS THROUGH EARLY WEEK. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... VFR AREAWIDE THIS MIDDAY AHEAD OF AN APPROACHING COLD FRONT. THE FRONT WILL GENERATE SHOWERS AND SCT TSTMS ACROSS THE NW MTNS THIS MID/LATE AFTERNOON WITH OCCASIONAL RESTRICTIONS AT KBFD...WITH DIMINISHING CHANCES LATE THIS AFTERNOON INTO EARLY EVENING FROM KAOO-KUNV-KIPT WITH ONLY LOCAL RESTRICTIONS POSS. THE SE WILL REMAIN VFR. FRONT CLEARS THE AREA THIS EVE...WITH NW/N FLOW ARRIVING BEHIND AS HIGH PRESSURE STARTS TO BUILD IN. THIS WILL PRODUCE CIG RESTRICTIONS ACROSS MAINLY NW HALF OF CWA...WITH IFR DEVELOPING AT KBFD-KJST AND MVFR FOR CENTRAL SECTIONS. OUTLOOK... SUN-WED...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE/RXR NEAR TERM...LA CORTE/RXR SHORT TERM...LA CORTE LONG TERM...LA CORTE/TYBURSKI AVIATION...MARTIN/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
133 PM EDT SAT SEP 19 2015 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE AREA TODAY. HIGH PRESSURE WILL BRING A RETURN OF NEAR NORMAL DAYTIME TEMPERATURES FOR SUNDAY AND CONTINUE INTO THE MIDDLE OF NEXT WEEK. AN UPPER LEVEL LOW MAY LEAD TO A FEW SHOWERS MONDAY OR TUESDAY OVER THE SOUTHERN MOUNTAINS. && .NEAR TERM /THROUGH TONIGHT/... EARLY THIS AFTERNOON...SURFACE LOW LIFTING OUT OF EASTERN GREAT LAKES WITH TRAILING COLD FRONT PROGRESSING ACROSS OHIO VALLEY /AT 17Z MOVING INTO CENTRAL OH/. THERE IS GOOD AGREEMENT ON THE TIMING OF THE FRONT...ENTERING WESTERN PA SHORTLY AFTER 18Z...AND MOVING INTO THE SUSQ VALLEY AROUND 03Z SUN. CONVECTION ALONG THE COLD FRONT WILL ORGANIZE TO OUR WEST AND ENTER THE NWRN MOUNTAINS DURING THE MID AFTERNOON. TOUGH TO FIND MUCH CAPE FURTHER EAST...SO SHOULD SEE A DEF WEAKENING TREND TO PRECIP AS FRONT SLIDES INTO THE ALLEGHENY FRONT AND CENTRAL MTNS. INTERESTING FEATURE FIRST HINTED AT BY THE LAST COUPLE RUNS OF THE HRRR /AND LIKELY WELL OVERDONE BY HRRR/ AND ON DISPLAY IN THE WV IS A VERY SUBTLE SHORTWAVE SLIDING FROM THE SOUTHERN TIP OF ILLINOIS AT 10Z TO SE OHIO AT 17Z BEGINNING TO SHOW SOME ENHANCED CLOUD HEIGHTS IN A NARROW DEFORMATION ZONE. THIS FEATURE WILL SLIDE NE IN QUICK MID-LEVEL FLOW OVER NEXT SEVERAL HOURS AND SHOULD BE ENOUGH TO KICK START SOME TSTMS OVER W PA WHERE CAPES ARE ONLY AROUND 500J/KG. IT REMAINS A BIT UNCLEAR JUST HOW FAR EAST OF A LINE FROM ABOUT BEDFORD TO STATE COLLEGE TO WILLIAMSPORT THE RAIN WILL MANAGE TO GET BEFORE PETERING OUT THOUGH...SO HELD ONTO SCT POPS THERE...RAMPING POPS HIGHER HEADING INTO NW MTNS. DID HOLD TSTM PROBS IN THE SCT CATEGORY...WITH FAST FLOW NOT TOTALLY RULING OUT AN ISOLATED STRONGER WIND GUST THERE /AS NOTED IN THE SPC DAY1 DISCUSSION CONCERNING A MARGINAL RISK/. WE`LL EEK OUT ONE MORE WARM DAY AHEAD OF THE COLD FRONT WITH HIGHS IN THE MID 70S TO MID 80S MOST LOCALES...WITH A SSW BREEZE OVER WESTERN SECTIONS. A COOL DOWN WILL BEGIN TONIGHT AS HIGH PRESSURE PUSHES QUICKLY INTO THE EASTERN GR LAKES AND SHOVES THE COLD FRONT OFF TO THE SOUTH. LOWS WILL RANGE FROM THE CHILLY MID 40S OVER THE NORTH TO AROUND 60 IN THE SOUTHEAST. OVER AREAS WHERE SKIES CLEAR TONIGHT...FOG SEEMS LIKELY LATE. THE BEST CHANCE WOULD SEEM TO BE OVER THE NORTHERN MOUNTAINS. && .SHORT TERM /SUNDAY/... CLOUDS WILL SETTLE OFF TO THE SOUTH SUNDAY AS HIGH PRESSURE QUICKLY MOVES INTO NORTHERN PA/SOUTHERN NY. IT WILL BE A MARKEDLY COOLER DAY WITH HIGHS AVERAGING AROUND 10 DEG COOLER THAN TODAY. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... CONFIDENCE IN THE EXTENDED FORECAST CONTINUES TO DWINDLE WITH EACH PASSING MODE RUN. EARLY IN THE PERIOD...MODELS AGREE IN BRINGING FAIRLY AMPLIFIED UPPER TROUGH THROUGH THE OHIO VALLEY INTO THE NERN US. THE RESULTING SOUTH-SOUTHEAST FLOW SHOULD BRING THE CHANCE OF SOME LIGHT RAINS FOR MONDAY AND POSSIBLY TUESDAY. AT THIS POINT I HAVE FAIRLY LOW CHANCES OF RAIN OVER MUCH OF THE AREA MONDAY AND MAINLY OVER SOUTHERN AREAS INTO TUESDAY. BEFORE THIS HAPPENS HOWEVER...WITH CLEAR SKIES...VERY DRY AIR AND LIGHT WINDS...LOWS OVER THE NWRN MOUNTAINS MONDAY MORNING WILL DROP DOWN INTO THE MIDDLE 30S. MAY SEE THE FIRST FROST OF THE SEASON IN A FEW OF THE NORMAL COLD SHELTERED LOCATIONS. FROM THERE MODEL SOLUTIONS DIVERGE FURTHER. THE ECMWF AND GFS/GEFS ALL SHOW THE UPPER TROUGH CLOSING OFF. WHAT HAPPENS THEN MEANS THE DIFFERENCE BETWEEN A MILD AND DRY REST OF THE WEEK...OR A COLD RAINY ONE. THE GFS/GEFS HAVE TRENDED MUCH FURTHER NORTH WITH THE UPPER LOW...KEEPING AN EXTENDED PERIOD OF MOIST EASTERLY LOW LEVEL FLOW FROM WEDNESDAY INTO FRIDAY. THIS WOULD RESULT IN A PERIOD OF CHILLY WET WEATHER. THE ECMWF ON THE OTHER HAND SETTLES THE LOW DOWN OVER THE SERN STATES AND EVEN TRACKS IT WEST ALONG THE GULF COAST FOR THE WEEKEND. THIS WOULD KEEP US UNDER FAVORABLE RIDGING NORTH OF THE SYSTEM...WITH DRY AND MILD CONDITIONS. I USED OUR SUPERBLENDED MODEL MOS WHICH DOWNPLAYS THE GFS/GEFS PESSIMISM...RESULTING IN A MUCH BRIGHTER FORECAST FROM MID WEEK ONWARD. PRESUMING THE OPTIMISTIC FORECAST VERIFIES...TEMPERATURES WHICH WILL START THE WEEK BELOW NORMAL WILL TREND BACK TO A BIT ABOVE NORMAL BY MID WEEK. && .AVIATION /18Z SATURDAY THROUGH WEDNESDAY/... VFR AREAWIDE THIS MIDDAY AHEAD OF AN APPROACHING COLD FRONT. THE FRONT WILL GENERATE SHOWERS AND SCT TSTMS ACROSS THE NW MTNS THIS MID/LATE AFTERNOON WITH OCCASIONAL RESTRICTIONS AT KBFD...WITH DIMINISHING CHANCES LATE THIS AFTERNOON INTO EARLY EVENING FROM KAOO-KUNV-KIPT WITH ONLY LOCAL RESTRICTIONS POSS. THE SE WILL REMAIN VFR. FRONT CLEARS THE AREA THIS EVE...WITH NW/N FLOW ARRIVING BEHIND AS HIGH PRESSURE STARTS TO BUILD IN. THIS WILL PRODUCE CIG RESTRICTIONS ACROSS MAINLY NW HALF OF CWA...WITH IFR DEVELOPING AT KBFD-KJST AND MVFR FOR CENTRAL SECTIONS. OUTLOOK... SUN-WED...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE/RXR NEAR TERM...LA CORTE/RXR SHORT TERM...LA CORTE LONG TERM...LA CORTE AVIATION...MARTIN/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
731 AM EDT SAT SEP 19 2015 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE AREA TODAY. HIGH PRESSURE WILL BRING A RETURN OF NEAR NORMAL DAYTIME TEMPERATURES FOR SUNDAY AND CONTINUE INTO THE MIDDLE OF NEXT WEEK. AN UPPER LEVEL LOW MAY LEAD TO A FEW SHOWERS MONDAY OR TUESDAY OVER THE SOUTHERN MOUNTAINS. && .NEAR TERM /THROUGH TONIGHT/... AS OF 3AM...THE SURFACE LOW WAS NEAR CHICAGO WITH THE COLD FRONT TRAILING SOUTH THROUGH ILLINOIS. THERE IS GOOD AGREEMENT ON THE TIMING OF THE FRONT...ENTERING WESTERN PA BY ABOUT 18Z...AND MOVING INTO THE SUSQ VALLEY BY 00Z. THERE IS ALSO GOOD AGREEMENT WITH THE PARENT UPPER SHORTWAVE SHEARING OUT THROUGH THE EASTERN LAKES AND SOUTHERN CANADA...LEADING TO A WEAKENING OF THE LARGE SCALE FORCING FOR THE SHOWERS AND THUNDERSTORMS CURRENTLY TRACKING EAST OVER CENTRAL LAKE ERIE DOWN INTO FAR NORTHERN OHIO. EXTRAPOLATION AND HRRR TIMING SUGGEST THESE BEGIN TO ENCROACH ON MY FAR NWRN ZONES BETWEEN ABOUT 7 AND 9 AM...11-13Z. THESE LEADING SHOWERS AND STORMS ARE MADE TO WEAKEN BY THE NEAR TERM MESO MODELS AS THEY MOVE OUT OF THE MOUNTAINS. ADDITIONAL CONVECTION ALONG THE COLD FRONT WILL ORGANIZE TO THE WEST AND ENTER THE NWRN MOUNTAINS ONCE AGAIN BY EARLY TO MID AFTERNOON...WITH A BETTER CHANCE OF SURVIVING INTO THE CENTRAL MOUNTAINS BY LATER TODAY AND THIS EVENING. THE WEAKENING TREND IN THE MODELS IS CONSISTENT AS THE FRONT PUSHES EAST...AND IT REMAINS UNCLEAR HOW MUCH EAST OF A LINE FROM ABOUT WILLIAMSPORT TO STATE COLLEGE TO ABOUT BEDFORD THE RAIN WILL MANAGE TO GET BEFORE PETERING OUT. THE HIGHEST CHANCES FOR RAIN WILL BE OVER NORTHERN AND NORTHWESTERN AREAS WHERE I HAVE CATEGORICAL POPS FOR TODAY. THE NUMBERS TAPER DOWN QUICKLY INTO THE CENTRAL MOUNTAINS AND LOWER STILL OVER MY SERN ZONES. QPF WILL RANGE FROM MEAGER AMOUNTS FROM THE MIDDLE SUSQUEHANNA VALLEY WEST TO THE LAURELS...TO PERHAPS .50" TO .75" OVER THE FAR NW. MODEST INSTABILITY AND MARGINAL WIND PROFILES SHOULD LIMIT SEVERE POTENTIAL TODAY...BUT SPC HAS PAINTED NWRN PA WITH A MARGINAL RISK FOR SEVERE STORMS TODAY. THE BEST CHANCE SEEMS TO BE IF A STRONG LINE CAN FORM IN OHIO/LOWER LAKES AND TRACK INTO THE REGION BEFORE IT DECAYS THIS EVENING. WE`LL EEK OUT ONE MORE WARM DAY AHEAD OF THE COLD FRONT WITH HIGHS IN THE MID 70S TO MID 80S. A COOL DOWN WILL BEGIN TONIGHT AS HIGH PRESSURE PUSHES QUICKLY INTO THE EASTERN GR LAKES AND SHOVES THE COLD FRONT OFF TO THE SOUTH. LOWS WILL RANGE FROM THE CHILLY MID 40S OVER THE NORTH TO AROUND 60 IN THE SOUTHEAST. OVER AREAS WHERE SKIES CLEAR TONIGHT...FOG SEEMS LIKELY LATE. THE BEST CHANCE WOULD SEEM TO BE OVER THE NORTHERN MOUNTAINS. && .SHORT TERM /SUNDAY/... CLOUDS WILL SETTLE OFF TO THE SOUTH SUNDAY AS HIGH PRESSURE QUICKLY MOVES INTO NORTHERN PA/SOUTHERN NY. IT WILL BE A MARKEDLY COOLER DAY WITH HIGHS AVERAGING AROUND 10 DEG COOLER THAN TODAY. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... CONFIDENCE IN THE EXTENDED FORECAST CONTINUES TO DWINDLE WITH EACH PASSING MODE RUN. EARLY IN THE PERIOD...MODELS AGREE IN BRINGING FAIRLY AMPLIFIED UPPER TROUGH THROUGH THE OHIO VALLEY INTO THE NERN US. THE RESULTING SOUTH-SOUTHEAST FLOW SHOULD BRING THE CHANCE OF SOME LIGHT RAINS FOR MONDAY AND POSSIBLY TUESDAY. AT THIS POINT I HAVE FAIRLY LOW CHANCES OF RAIN OVER MUCH OF THE AREA MONDAY AND MAINLY OVER SOUTHERN AREAS INTO TUESDAY. BEFORE THIS HAPPENS HOWEVER...WITH CLEAR SKIES...VERY DRY AIR AND LIGHT WINDS...LOWS OVER THE NWRN MOUNTAINS MONDAY MORNING WILL DROP DOWN INTO THE MIDDLE 30S. MAY SEE THE FIRST FROST OF THE SEASON IN A FEW OF THE NORMAL COLD SHELTERED LOCATIONS. FROM THERE MODEL SOLUTIONS DIVERGE FURTHER. THE ECMWF AND GFS/GEFS ALL SHOW THE UPPER TROUGH CLOSING OFF. WHAT HAPPENS THEN MEANS THE DIFFERENCE BETWEEN A MILD AND DRY REST OF THE WEEK...OR A COLD RAINY ONE. THE GFS/GEFS HAVE TRENDED MUCH FURTHER NORTH WITH THE UPPER LOW...KEEPING AN EXTENDED PERIOD OF MOIST EASTERLY LOW LEVEL FLOW FROM WEDNESDAY INTO FRIDAY. THIS WOULD RESULT IN A PERIOD OF CHILLY WET WEATHER. THE ECMWF ON THE OTHER HAND SETTLES THE LOW DOWN OVER THE SERN STATES AND EVEN TRACKS IT WEST ALONG THE GULF COAST FOR THE WEEKEND. THIS WOULD KEEP US UNDER FAVORABLE RIDGING NORTH OF THE SYSTEM...WITH DRY AND MILD CONDITIONS. I USED OUR SUPERBLENDED MODEL MOS WHICH DOWNPLAYS THE GFS/GEFS PESSIMISM...RESULTING IN A MUCH BRIGHTER FORECAST FROM MID WEEK ONWARD. PRESUMING THE OPTIMISTIC FORECAST VERIFIES...TEMPERATURES WHICH WILL START THE WEEK BELOW NORMAL WILL TREND BACK TO A BIT ABOVE NORMAL BY MID WEEK. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... SEVERAL BANDS OF SHOWERS AND STORMS EARLY...MAINLY ACROSS THE NW...GIVEN DYNAMICS. SOME FOG FOR A FEW MORE HOURS...BUT NOT AS EXTENSIVE AS THE LAST 2 MORNINGS. MAIN AREA FOR DENSE FOG AT TIMES HAS BEEN LNS. MOST OF THE DAY WILL BE DRY WITH VFR CONDITIONS. A COLD FRONT MOVING SE MAY BRING SOME MORE SHOWERS LATE. LOW CIGS POSSIBLE TONIGHT...BEHIND THE COLD FRONT. WEATHER NOT LOOKING BAD SUN INTO WED. OUTLOOK... SUN-WED...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LA CORTE AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
523 AM EDT SAT SEP 19 2015 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE AREA TODAY. HIGH PRESSURE WILL BRING A RETURN OF NEAR NORMAL DAYTIME TEMPERATURES FOR SUNDAY AND CONTINUE INTO THE MIDDLE OF NEXT WEEK. AN UPPER LEVEL LOW MAY LEAD TO A FEW SHOWERS MONDAY OR TUESDAY OVER THE SOUTHERN MOUNTAINS. && .NEAR TERM /THROUGH TONIGHT/... AS OF 3AM...THE SURFACE LOW WAS NEAR CHICAGO WITH THE COLD FRONT TRAILING SOUTH THROUGH ILLINOIS. THERE IS GOOD AGREEMENT ON THE TIMING OF THE FRONT...ENTERING WESTERN PA BY ABOUT 18Z...AND MOVING INTO THE SUSQ VALLEY BY 00Z. THERE IS ALSO GOOD AGREEMENT WITH THE PARENT UPPER SHORTWAVE SHEARING OUT THROUGH THE EASTERN LAKES AND SOUTHERN CANADA...LEADING TO A WEAKENING OF THE LARGE SCALE FORCING FOR THE SHOWERS AND THUNDERSTORMS CURRENTLY TRACKING EAST OVER CENTRAL LAKE ERIE DOWN INTO FAR NORTHERN OHIO. EXTRAPOLATION AND HRRR TIMING SUGGEST THESE BEGIN TO ENCROACH ON MY FAR NWRN ZONES BETWEEN ABOUT 7 AND 9 AM...11-13Z. THESE LEADING SHOWERS AND STORMS ARE MADE TO WEAKEN BY THE NEAR TERM MESO MODELS AS THEY MOVE OUT OF THE MOUNTAINS. ADDITIONAL CONVECTION ALONG THE COLD FRONT WILL ORGANIZE TO THE WEST AND ENTER THE NWRN MOUNTAINS ONCE AGAIN BY EARLY TO MID AFTERNOON...WITH A BETTER CHANCE OF SURVIVING INTO THE CENTRAL MOUNTAINS BY LATER TODAY AND THIS EVENING. THE WEAKENING TREND IN THE MODELS IS CONSISTENT AS THE FRONT PUSHES EAST...AND IT REMAINS UNCLEAR HOW MUCH EAST OF A LINE FROM ABOUT WILLIAMSPORT TO STATE COLLEGE TO ABOUT BEDFORD THE RAIN WILL MANAGE TO GET BEFORE PETERING OUT. THE HIGHEST CHANCES FOR RAIN WILL BE OVER NORTHERN AND NORTHWESTERN AREAS WHERE I HAVE CATEGORICAL POPS FOR TODAY. THE NUMBERS TAPER DOWN QUICKLY INTO THE CENTRAL MOUNTAINS AND LOWER STILL OVER MY SERN ZONES. QPF WILL RANGE FROM MEAGER AMOUNTS FROM THE MIDDLE SUSQUEHANNA VALLEY WEST TO THE LAURELS...TO PERHAPS .50" TO .75" OVER THE FAR NW. MODEST INSTABILITY AND MARGINAL WIND PROFILES SHOULD LIMIT SEVERE POTENTIAL TODAY...BUT SPC HAS PAINTED NWRN PA WITH A MARGINAL RISK FOR SEVERE STORMS TODAY. THE BEST CHANCE SEEMS TO BE IF A STRONG LINE CAN FORM IN OHIO/LOWER LAKES AND TRACK INTO THE REGION BEFORE IT DECAYS THIS EVENING. WE`LL EEK OUT ONE MORE WARM DAY AHEAD OF THE COLD FRONT WITH HIGHS IN THE MID 70S TO MID 80S. A COOL DOWN WILL BEGIN TONIGHT AS HIGH PRESSURE PUSHES QUICKLY INTO THE EASTERN GR LAKES AND SHOVES THE COLD FRONT OFF TO THE SOUTH. LOWS WILL RANGE FROM THE CHILLY MID 40S OVER THE NORTH TO AROUND 60 IN THE SOUTHEAST. OVER AREAS WHERE SKIES CLEAR TONIGHT...FOG SEEMS LIKELY LATE. THE BEST CHANCE WOULD SEEM TO BE OVER THE NORTHERN MOUNTAINS. && .SHORT TERM /SUNDAY/... CLOUDS WILL SETTLE OFF TO THE SOUTH SUNDAY AS HIGH PRESSURE QUICKLY MOVES INTO NORTHERN PA/SOUTHERN NY. IT WILL BE A MARKEDLY COOLER DAY WITH HIGHS AVERAGING AROUND 10 DEG COOLER THAN TODAY. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... CONFIDENCE IN THE EXTENDED FORECAST CONTINUES TO DWINDLE WITH EACH PASSING MODE RUN. EARLY IN THE PERIOD...MODELS AGREE IN BRINGING FAIRLY AMPLIFIED UPPER TROUGH THROUGH THE OHIO VALLEY INTO THE NERN US. THE RESULTING SOUTH-SOUTHEAST FLOW SHOULD BRING THE CHANCE OF SOME LIGHT RAINS FOR MONDAY AND POSSIBLY TUESDAY. AT THIS POINT I HAVE FAIRLY LOW CHANCES OF RAIN OVER MUCH OF THE AREA MONDAY AND MAINLY OVER SOUTHERN AREAS INTO TUESDAY. BEFORE THIS HAPPENS HOWEVER...WITH CLEAR SKIES...VERY DRY AIR AND LIGHT WINDS...LOWS OVER THE NWRN MOUNTAINS MONDAY MORNING WILL DROP DOWN INTO THE MIDDLE 30S. MAY SEE THE FIRST FROST OF THE SEASON IN A FEW OF THE NORMAL COLD SHELTERED LOCATIONS. FROM THERE MODEL SOLUTIONS DIVERGE FURTHER. THE ECMWF AND GFS/GEFS ALL SHOW THE UPPER TROUGH CLOSING OFF. WHAT HAPPENS THEN MEANS THE DIFFERENCE BETWEEN A MILD AND DRY REST OF THE WEEK...OR A COLD RAINY ONE. THE GFS/GEFS HAVE TRENDED MUCH FURTHER NORTH WITH THE UPPER LOW...KEEPING AN EXTENDED PERIOD OF MOIST EASTERLY LOW LEVEL FLOW FROM WEDNESDAY INTO FRIDAY. THIS WOULD RESULT IN A PERIOD OF CHILLY WET WEATHER. THE ECMWF ON THE OTHER HAND SETTLES THE LOW DOWN OVER THE SERN STATES AND EVEN TRACKS IT WEST ALONG THE GULF COAST FOR THE WEEKEND. THIS WOULD KEEP US UNDER FAVORABLE RIDGING NORTH OF THE SYSTEM...WITH DRY AND MILD CONDITIONS. I USED OUR SUPERBLENDED MODEL MOS WHICH DOWNPLAYS THE GFS/GEFS PESSIMISM...RESULTING IN A MUCH BRIGHTER FORECAST FROM MID WEEK ONWARD. PRESUMING THE OPTIMISTIC FORECAST VERIFIES...TEMPERATURES WHICH WILL START THE WEEK BELOW NORMAL WILL TREND BACK TO A BIT ABOVE NORMAL BY MID WEEK. && .AVIATION /09Z SATURDAY THROUGH WEDNESDAY/... 09Z TAFS SENT. SOME SHOWERS MOVING TOWARD BFD. ADJUSTED THIS TAF. THE ACTIVITY SHOULD WEAKEN...AS THE SHOWERS MOVE AWAY FROM THE BETTER DYNAMICS AND MOISTURE. EARLIER DISCUSSION BELOW. RIDGE OF HIGH PRESSURE ALONG THE EAST COAST WILL ENSURE ANOTHER NIGHT OF FAIR WEATHER AND LIGHT WIND ACROSS CENTRAL PA. MAIN AVIATION CONCERN WILL BE EARLY AM FOG...FOCUSED MAINLY ACROSS SOUTHEAST PA...DIRECTLY BENEATH RETREATING SFC RIDGE. A DEVELOPING SOUTHERLY BREEZE AND PATCHY MID LVL CLOUDS WORKING INTO THE WESTERN HALF OF THE STATE SHOULD LIMIT THE FOG POTENTIAL FROM THE CENTRAL MTNS WESTWARD. LATEST HRRR/NAM/LAMP...AS WELL AS LATEST SREF...ALL SUPPORT A LIKELY PERIOD OF IFR/LIFR CONDS AT KLNS BTWN 09Z-14Z. CAN/T RULE OUT OF BRIEF PERIOD OF IFR CONDS AT KIPT/KMDT ARND DAWN. HOWEVER...CONFIDENCE NOT AS HIGH. ANY FOG ACROSS SOUTHEAST PA SHOULD LIFT BY LATE AM. FOCUS WILL THEN SHIFT TOWARD A COLD FRONT PUSHING INTO NORTHWEST PA LATE IN THE DAY. A WEAKENING BAND OF SHRA/TSRA WILL LIKELY PRODUCE A BRIEF VIS REDUCTION AT KBFD LATE IN THE DAY...AND POSSIBLY AT KIPT/KUNV/KAOO/KJST ARND 00Z. OUTLOOK... SUN-WED...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LA CORTE AVIATION...FITZGERALD/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
428 AM EDT SAT SEP 19 2015 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE AREA TODAY. HIGH PRESSURE WILL BRING A RETURN OF NEAR NORMAL DAYTIME TEMPERATURES FOR SUNDAY AND CONTINUE INTO THE MIDDLE OF NEXT WEEK. AN UPPER LEVEL LOW MAY LEAD TO A FEW SHOWERS MONDAY OR TUESDAY OVER THE SOUTHERN MOUNTAINS. && .NEAR TERM /THROUGH TONIGHT/... AS OF 3AM...THE SURFACE LOW WAS NEAR CHICAGO WITH THE COLD FRONT TRAILING SOUTH THROUGH ILLINOIS. THERE IS GOOD AGREEMENT ON THE TIMING OF THE FRONT...ENTERING WESTERN PA BY ABOUT 18Z...AND MOVING INTO THE SUSQ VALLEY BY 00Z. THERE IS ALSO GOOD AGREEMENT WITH THE PARENT UPPER SHORTWAVE SHEARING OUT THROUGH THE EASTERN LAKES AND SOUTHERN CANADA...LEADING TO A WEAKENING OF THE LARGE SCALE FORCING FOR THE SHOWERS AND THUNDERSTORMS CURRENTLY TRACKING EAST OVER CENTRAL LAKE ERIE DOWN INTO FAR NORTHERN OHIO. EXTRAPOLATION AND HRRR TIMING SUGGEST THESE BEGIN TO ENCROACH ON MY FAR NWRN ZONES BETWEEN ABOUT 7 AND 9 AM...11-13Z. THESE LEADING SHOWERS AND STORMS ARE MADE TO WEAKEN BY THE NEAR TERM MESO MODELS AS THEY MOVE OUT OF THE MOUNTAINS. ADDITIONAL CONVECTION ALONG THE COLD FRONT WILL ORGANIZE TO THE WEST AND ENTER THE NWRN MOUNTAINS ONCE AGAIN BY EARLY TO MID AFTERNOON...WITH A BETTER CHANCE OF SURVIVING INTO THE CENTRAL MOUNTAINS BY LATER TODAY AND THIS EVENING. THE WEAKENING TREND IN THE MODELS IS CONSISTENT AS THE FRONT PUSHES EAST...AND IT REMAINS UNCLEAR HOW MUCH EAST OF A LINE FROM ABOUT WILLIAMSPORT TO STATE COLLEGE TO ABOUT BEDFORD THE RAIN WILL MANAGE TO GET BEFORE PETERING OUT. THE HIGHEST CHANCES FOR RAIN WILL BE OVER NORTHERN AND NORTHWESTERN AREAS WHERE I HAVE CATEGORICAL POPS FOR TODAY. THE NUMBERS TAPER DOWN QUICKLY INTO THE CENTRAL MOUNTAINS AND LOWER STILL OVER MY SERN ZONES. QPF WILL RANGE FROM MEAGER AMOUNTS FROM THE MIDDLE SUSQUEHANNA VALLEY WEST TO THE LAURELS...TO PERHAPS .50" TO .75" OVER THE FAR NW. MODEST INSTABILITY AND MARGINAL WIND PROFILES SHOULD LIMIT SEVERE POTENTIAL TODAY...BUT SPC HAS PAINTED NWRN PA WITH A MARGINAL RISK FOR SEVERE STORMS TODAY. THE BEST CHANCE SEEMS TO BE IF A STRONG LINE CAN FORM IN OHIO/LOWER LAKES AND TRACK INTO THE REGION BEFORE IT DECAYS THIS EVENING. WE`LL EEK OUT ONE MORE WARM DAY AHEAD OF THE COLD FRONT WITH HIGHS IN THE MID 70S TO MID 80S. A COOL DOWN WILL BEGIN TONIGHT AS HIGH PRESSURE PUSHES QUICKLY INTO THE EASTERN GR LAKES AND SHOVES THE COLD FRONT OFF TO THE SOUTH. LOWS WILL RANGE FROM THE CHILLY MID 40S OVER THE NORTH TO AROUND 60 IN THE SOUTHEAST. OVER AREAS WHERE SKIES CLEAR TONIGHT...FOG SEEMS LIKELY LATE. THE BEST CHANCE WOULD SEEM TO BE OVER THE NORTHERN MOUNTAINS. && .SHORT TERM /SUNDAY/... CLOUDS WILL SETTLE OFF TO THE SOUTH SUNDAY AS HIGH PRESSURE QUICKLY MOVES INTO NORTHERN PA/SOUTHERN NY. IT WILL BE A MARKEDLY COOLER DAY WITH HIGHS AVERAGING AROUND 10 DEG COOLER THAN TODAY. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... CONFIDENCE IN THE EXTENDED FORECAST CONTINUES TO DWINDLE WITH EACH PASSING MODE RUN. EARLY IN THE PERIOD...MODELS AGREE IN BRINGING FAIRLY AMPLIFIED UPPER TROUGH THROUGH THE OHIO VALLEY INTO THE NERN US. THE RESULTING SOUTH-SOUTHEAST FLOW SHOULD BRING THE CHANCE OF SOME LIGHT RAINS FOR MONDAY AND POSSIBLY TUESDAY. AT THIS POINT I HAVE FAIRLY LOW CHANCES OF RAIN OVER MUCH OF THE AREA MONDAY AND MAINLY OVER SOUTHERN AREAS INTO TUESDAY. BEFORE THIS HAPPENS HOWEVER...WITH CLEAR SKIES...VERY DRY AIR AND LIGHT WINDS...LOWS OVER THE NWRN MOUNTAINS MONDAY MORNING WILL DROP DOWN INTO THE MIDDLE 30S. MAY SEE THE FIRST FROST OF THE SEASON IN A FEW OF THE NORMAL COLD SHELTERED LOCATIONS. FROM THERE MODEL SOLUTIONS DIVERGE FURTHER. THE ECMWF AND GFS/GEFS ALL SHOW THE UPPER TROUGH CLOSING OFF. WHAT HAPPENS THEN MEANS THE DIFFERENCE BETWEEN A MILD AND DRY REST OF THE WEEK...OR A COLD RAINY ONE. THE GFS/GEFS HAVE TRENDED MUCH FURTHER NORTH WITH THE UPPER LOW...KEEPING AN EXTENDED PERIOD OF MOIST EASTERLY LOW LEVEL FLOW FROM WEDNESDAY INTO FRIDAY. THIS WOULD RESULT IN A PERIOD OF CHILLY WET WEATHER. THE ECMWF ON THE OTHER HAND SETTLES THE LOW DOWN OVER THE SERN STATES AND EVEN TRACKS IT WEST ALONG THE GULF COAST FOR THE WEEKEND. THIS WOULD KEEP US UNDER FAVORABLE RIDGING NORTH OF THE SYSTEM...WITH DRY AND MILD CONDITIONS. I USED OUR SUPERBLENDED MODEL MOS WHICH DOWNPLAYS THE GFS/GEFS PESSIMISM...RESULTING IN A MUCH BRIGHTER FORECAST FROM MID WEEK ONWARD. PRESUMING THE OPTIMISTIC FORECAST VERIFIES...TEMPERATURES WHICH WILL START THE WEEK BELOW NORMAL WILL TREND BACK TO A BIT ABOVE NORMAL BY MID WEEK. && .AVIATION /08Z SATURDAY THROUGH WEDNESDAY/... 06Z TAFS SENT. EARLIER DISCUSSION BELOW. RIDGE OF HIGH PRESSURE ALONG THE EAST COAST WILL ENSURE ANOTHER NIGHT OF FAIR WEATHER AND LIGHT WIND ACROSS CENTRAL PA. MAIN AVIATION CONCERN WILL BE EARLY AM FOG...FOCUSED MAINLY ACROSS SOUTHEAST PA...DIRECTLY BENEATH RETREATING SFC RIDGE. A DEVELOPING SOUTHERLY BREEZE AND PATCHY MID LVL CLOUDS WORKING INTO THE WESTERN HALF OF THE STATE SHOULD LIMIT THE FOG POTENTIAL FROM THE CENTRAL MTNS WESTWARD. LATEST HRRR/NAM/LAMP...AS WELL AS LATEST SREF...ALL SUPPORT A LIKELY PERIOD OF IFR/LIFR CONDS AT KLNS BTWN 09Z-14Z. CAN/T RULE OUT OF BRIEF PERIOD OF IFR CONDS AT KIPT/KMDT ARND DAWN. HOWEVER...CONFIDENCE NOT AS HIGH. ANY FOG ACROSS SOUTHEAST PA SHOULD LIFT BY LATE AM. FOCUS WILL THEN SHIFT TOWARD A COLD FRONT PUSHING INTO NORTHWEST PA LATE IN THE DAY. A WEAKENING BAND OF SHRA/TSRA WILL LIKELY PRODUCE A BRIEF VIS REDUCTION AT KBFD LATE IN THE DAY...AND POSSIBLY AT KIPT/KUNV/KAOO/KJST ARND 00Z. OUTLOOK... SUN-WED...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LA CORTE AVIATION...FITZGERALD/MARTIN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
140 AM EDT SAT SEP 19 2015 .SYNOPSIS... HIGH PRESSURE WILL REMAIN IN PLACE THROUGH TOMORROW. A COLD FRONT WILL MOVE INTO THE CAROLINAS FROM THE NORTH ON SUNDAY WITH PRECIPITATION CHANCES INCREASING FOR SUNDAY AND MONDAY. COOLER TEMPERATURES WILL ALSO RETURN ON MONDAY...WITH PERIODIC CHANCES FOR PRECIPITATION CONTINUING INTO THE MIDDLE OF NEXT WEEK. && .NEAR TERM /THROUGH TODAY/... AS OF 130 AM...ALL QUIET THUS FAR. VALLEY FOG DEVELOPING IN THE LITTLE TN RIVER VALLEY...AS EXPECTED. TEMP TRENDS LOOK OK. NO CHANGES. AS OF 1030 PM...ANOTHER CLEAR NIGHT ACROSS THE FORECAST AREA AS DRY SURFACE RIDGE REMAINS THE DOMINANT SYNOPTIC SCALE FEATURE ACROSS THE AREA. SLOWLY BUT SURELY INCREASING DEWPOINTS/LOW LEVEL THICKNESS VALUES SHOULD YIELD MIN TEMPS ABOUT A DEGREE WARMER THAN FRIDAY MORNING...OR WITHIN A DEGREE OR SO OF CLIMO. OTHERWISE...FOG/LOW STRATUS SHOULD DEVELOP/EXPAND ACROSS THE LITTLE TENN VALLEY AND ADJACENT DRAINAGES OVER THE NEXT COUPLE OF HOURS...BUT REMAIN SPORADIC ACROSS MOST OF THE OTHER MAJOR VALLEYS. AS OF 735 PM...DEWPOINTS MIXED OUT A BIT THIS AFTERNOON...SO ITS ANOTHER DECENT LATE SUMMER EVENING ACROSS THE FORECAST AREA...WITH LITTLE IN THE WAY OF CLOUD COVER NOW THAT AFTERNOON CU HAS MOSTLY DISSIPATED. TEMPS SHOULD BE IN THE 60S ACROSS MUCH OF THE AREA BY MIDNIGHT. AS OF 230 PM EDT...THE 500 MB RIDGE AXIS OVER THE SRN APPALACHIANS TONIGHT WILL SLOWLY BREAK DOWN FROM THE NORTHWEST ON SATURDAY AS THE NORTHERN TIER BELT OF WESTERLIES SPREADS SOUTHWARD. THE SURFACE HIGH OVER THE FORECAST AREA WILL GET INCREASINGLY PINCHED OVERHEAD BETWEEN LOW PRESSURE OVER THE COASTAL WATERS AND A COLD FRONT APPROACHING FROM THE OH VALLEY. PROFILES OVER OUR AREA WILL STAY RELATIVELY DRY...ALTHOUGH THE NAM AND RAP DO INDICATE PATCHY LOWER STRATUS TRYING TO MAKE A RUN WESTWARD FROM THE COAST INTO THE PIEDMONT OVERNIGHT. MOST CLOUDINESS THROUGH THE PERIOD...HOWEVER... SHOULD BE CONFINED MAINLY TO EARLY MORNING MOUNTAIN VALLEY STRATUS AND THEN A FEW DAYTIME CUMULUS WITH HEATING SATURDAY AFTERNOON. TEMPERATURES WILL CONTINUE TO REBOUND...WITH MINS AT LEAST A CATEGORY ABOVE CLIMO THROUGHOUT OVERNIGHT...AND TWO TO THREE CATEGORIES ABOVE CLIMO FOR MAX TEMPS SATURDAY AFTERNOON. && .SHORT TERM /TONIGHT THROUGH MONDAY/... AS OF 245 PM...A DISTURBANCE WILL REMAIN OFF THE CAROLINA COAST THROUGH THE SHORT RANGE...RESULTING IN LITTLE CHANGE TO THE SENSIBLE WEATHER OVER THE CWA. ON SUNDAY...A WEAK COLD FRONT WILL SWEEP FROM THE NORTHWEST...LIKELY REMAINING WEST OF THE FA BY SUNSET. SKY COVER WILL INCREASE ACROSS THE SOUTHERN APPALACHIAN REGION THROUGH THE DAY. LITTLE TO NO INSTABILITY AND NO FORCING SHOULD RESULT IN DRY WEATHER ON SUNDAY. HIGH TEMPERATURES SHOULD RANGE FROM THE L80S WITHIN THE MTN VALLEYS TO THE U80S EAST. THE WEAK COLD FRONT WILL LIKELY HANG OVER THE SOUTHERN APPALACHIANS EARLY MONDAY MORNING. THE CENTER OF SFC HIGH PRESSURE OVER NEW ENGLAND...THE RIDGE OVER THE REGION ON MONDAY. THE GFS INDICATE THAT WEAK 300 K ISENTROPIC LIFT WILL DEVELOP ACROSS THE REGION DURING THE DAYLIGHT HOURS...SUPPORTED BY LLVL SE FLOW. THE COMBINATION OF ISENTROPIC LIFT...LIGHT UPSLOPE FLOW...AND WIDESPREAD WEAK INSTABILITY SHOULD RESULT IN AN EXPANDING AREA OF SHRA/TSRA ON MONDAY. THICK CLOUDS...RAINFALL...AND DEVELOPING NE SFC WINDS WILL FAVOR HIGH TEMPERATURES BELOW THE MOS CONSENSUS. I WILL FORECAST HIGH TEMPERATURES FROM THE L70S WITHIN THE MTN VALLEYS TO THE L80S ACROSS THE LAKELANDS. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... AS OF 210 PM FRIDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON TUESDAY WITH AN UPPER TROF AXIS JUST TO OUR WEST AND UPPER RIDGING OVER THE WESTERN CONUS. OVER THE NEXT COUPLE OF DAYS...THE TROF IS EXPECTED TO SLOWLY MOVE OVER THE FCST AREA AND MORPH INTO A CLOSED UPPER LOW BY LATE WED. THE LONG RANGE MODELS KEEP THE LOW SPINNING OVER THE SE REGION INTO FRI WITH BROAD SCALE UPPER RIDGING SPREADING FARTHER EAST OVER THE SAME PERIOD. IT IS NOTABLE THAT THE LATEST 12Z RUN OF THE GFS DOES TRY TO MAINTAIN THE CLOSED LOW ABOUT 24 TO 48 HRS LONGER THAN THE OLDER RUN OF THE ECWMF. AT THE SFC...CANADIAN HIGH PRESSURE WILL BE SLIDING OFF THE NEW ENGLAND COAST BY EARLY TUES WITH A BROAD LOW CENTERED JUST OFF THE CAROLINA COAST. THE EVOLUTION OF THE SFC PATTERN REMAINS FAIRLY UNCLEAR AT THIS POINT...WITH SIG DIFFERENCES BETWEEN THE LONG RANGE MODELS. THE GFS AND THE CMC KEEP THE LOW JUST OFFSHORE WELL INTO THURS WITH ANOTHER CANADIAN HIGH SLIDING EASTWARD IN THE WAKE OF THE PREVIOUS SFC HIGH. THE LOW EVENTUALLY DISSIPATES OVER THE CWFA BY FRI WITH AN EVEN STRONGER HIGH MAKING ITS WAY SOUTHWARD AND TOWARDS THE GREAT LAKES BY THE END OF THE PERIOD. ON THE OTHER HAND...THE ECMWF MOVES THE LOW UP THE EAST COAST ON TUES AND THEN WELL OFFSHORE BY LATE WED ALL WHILE KEEPING HIGH PRESSURE OVER THE FCST AREA THRU THE ENTIRE PERIOD. AS FOR THE SENSIBLE FCST...MORE WEIGHT HAS BEEN PLACED ON A GFS TYPE SOLUTION WITH THE BEST CHANCES FOR PRECIP DURING THE FIRST DAY OR 2 OF THE PERIOD. TEMPS APPEAR MORE CONSISTENT BETWEEN THE MODELS WITH VALUES WARMING A FEW DEGREES THRU THE MEDIUM RANGE NEARING CLIMATOLOGY VALUES FOR MID/LATE SEPT. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... AT KCLT AND ELSEWHERE...VFR THRU THE PERIOD. HIGH PRESSURE TO THE NE WILL KEEP A LIGHT N OR NE WIND ACROSS THE REGION THRU SATURDAY EVENING. STILL A POSSIBILITY THAT SOME LOW CLOUDINESS WILL MOVE TOWARD KCLT BY DAYBREAK...BUT EXPECT THAT EVEN IF IT DOES HAPPEN...CLOUD BASE WILL BE VFR. STILL CANNOT RULE OUT VALLEY FOG/LOW STRATUS AT KAVL AROUND DAYBREAK...BUT GOING WITH PERSISTENCE ONCE AGAIN...HAVE LIMITED THE RESTRICTION TO A TEMPO. A FEW STRATOCU MAY DEVELOP AT 060 OR ABOVE THIS AFTERNOON ACROSS THE REGION. OTHERWISE...CLEAR SKY. OUTLOOK...THE POSSIBILITY OF MORNING MOUNTAIN VALLEY FOG AND LOW STRATUS WILL CONTINUE SAT NIGHT INTO SUNDAY MORNING. A COLD FRONT WILL APPROACH FROM THE NORTHWEST ON SUNDAY...AND A DEVELOPING MID LEVEL LOW MAY INCREASE THE CHANCES OF LOW CLOUDS AND RAIN ACROSS THE REGION EARLY TO MIDDLE NEXT WEEK. CONFIDENCE TABLE... 05-11Z 11-17Z 17-23Z 23-00Z 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 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...JPT NEAR TERM...HG/JDL/PM SHORT TERM...NED LONG TERM...JPT AVIATION...PM
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1231 PM CDT SAT SEP 19 2015 .UPDATE...LATEST HRRR CONTINUES TO PAINT A VERY SKIMPY PRECIP PATTERN OVER THE MID STATE THIS AFTERNOON AND EVENING. SO, WILL LEAVE OUR LOW POP FCST IN PLACE. SHORTLY AFTER NOON, AREA RADARS SHOWED ISOLATED SHOWERS IMMEDIATELY BEHIND THE FRONT OVER NORTHWESTERN TENNESSEE. SINCE CLOUDS ARE RELATIVELY HIGH AND THIN AHEAD OF THE FRONT, TEMPS ARE WARMING NICELY IN THE W-SWLY PRE- FRONTAL FLOW. THUS, HAVE ADJUSTED MAX TEMP EXPECTATIONS UP A FEW DEGS FOR THIS AFTERNOON OVER SOUTHERN AND EASTERN AREAS (INCLUDING THE NASHVILLE AREA). NEW SUITE OF PRODUCTS, REFLECTING THESE UPDATES, HAS ALREADY BEEN ISSUED. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 90 62 80 59 / 20 20 10 10 CLARKSVILLE 84 58 78 54 / 30 10 10 10 CROSSVILLE 83 62 77 57 / 10 20 20 10 COLUMBIA 90 63 80 58 / 20 20 10 10 LAWRENCEBURG 88 63 80 59 / 10 20 10 10 WAVERLY 86 59 78 56 / 20 10 10 10 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 19
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
540 AM CDT SAT SEP 19 2015 .UPDATE...FOR 12Z AVIATION DISCUSSION. && .AVIATION UPDATE...12Z AVIATION DISCUSSION. FIGURING IN SUBTLE MODEL DISCREPANCIES ON SFC FRONTAL PASSAGE TIMING... INCLUDING BELOW REFERENCED LIMITED MOISTURE POTENTIAL ALSO...BELIEVE AT BEST TAF SITES WILL EXPERIENCE MAINLY VFR CB CEILINGS WITH VCTS 19/16Z W TO 19/22Z E. ACTUAL CLRING TIMING AMOUNT OF POSSIBLE CEILING EROSION STILL IN QUESTION BEHIND SFC FRONTAL PASSAGE...BUT BELIEVE BECAUSE OF LATE AFTERNOON MIXING POTENTIAL CKV...A TRANSITION TO SCT AC OR SKC CONDITIONS POSSIBLE BY NO LATER THAN 20/03Z. VFR BKN STRATUS CEILINGS SHOULD PERSIST BNA THRU AT LEAST 20/10Z WITH A TRANSITION FROM HIGH END MVFR CEILINGS TO IFR CEILINGS CSV WITH MVFR FOG INDUCED VSBYS POSSIBLY 20/10Z. && PREV DISCUSSION.../ISSUED 354 AM CDT SAT SEP 19 2015/ DISCUSSION... SHORT TERM(TODAY-MON)... COLD FRONT IS CURRENTLY POSITIONED FROM CHI TOWN SW ACROSS NORTHERN TX. UPPER RIDGE AXIS ACROSS THE SOUTHEASTERN U.S. WILL BE SINKING SOUTHWARD AND UPPER LEVEL WESTERLIES SHOULD PREVAIL BY AFTERNOON. THIS WILL ACT TO MOVE THE FRONT OUR WAY. FROPA IS EXPECTED DURING THE LATE AFTERNOON HOURS. MOISTURE AVAILABILITY FOR THE APPROACHING FRONT WILL BE VERY LIMITED. IT DOES APPEAR THAT JUST ENOUGH INSTABILITY WILL RESIDE SO AS TO PROMOTE A LOW 20 POP FOR MOST OF THE AREA FOR TODAY AND THIS EVENING. THE ASSOCIATED UPPER LEVEL DYNAMICS WILL TAKE A NORTHERLY ROUTE...WELL NORTH OF TN. HRRR IS VERY STINGY WITH ANY APPRECIABLE PRECIP WITH THIS SYSTEM. WILL THEREFORE KEEP THE EXPECTED QPF FIELDS ON THE LOW SIDE. AT ANY RATE...CLOUDS WILL INCREASE SLOWLY BETWEEN NOW AND THIS EVENING. MOSTLY CLOUDY SKIES SHOULD PREVAIL FOR TONIGHT AND EARLY SUNDAY. THEN...WE`LL LEAN TOWARD PARTIAL CLOUD COVER. FOR THE NEAR TERM TEMPS...WARM AGAIN FOR TODAY. HIGHS WILL BE WELL INTO THE 80S FOR MOST AREAS. THE COOL DOWN WILL BEGIN TONIGHT AFTER THE FROPA. SUNDAY AND MONDAY WILL FEATURE HIGHS NEAR 80 WEST OF PLATEAU...WITH DEW POINTS IN THE 50S. OVERNIGHT LOWS WILL GENERALLY BE FROM 55 TO 60 FOR SUNDAY NIGHT...ABOUT 5 DEGREES COOLER THAN SAT NT. LONG TERM(TUE-SAT)... DISCREPANCIES BETWEEN MODEL SOLUTIONS STILL REMAIN WITH THIS MORNING`S RUNS...BUT A GENERAL TREND FOR MID TO LATER PORTIONS OF THE WORK WEEK TOWARD A COMPLETELY DRY FORECAST...WITH THE ONLY POTENTIAL OF RAINFALL POSSIBLY THE FIRST PART OF NEXT WEEKEND...AND EVEN THEN ONLY A SLIGHT CHANCE OF SHWRS ACROSS THE ERN HALF OF THE MID STATE. TEMPS WILL GENERALLY BE AROUND OR MAYBE A FEW DEGREES HERE AND THERE ABOVE SEASONAL NORMAL VALUES. MOSTLY CLEAR TO PTCLDY SKIES ARE CONTINUED TO BE EXPECTED THRU THIS PERIOD TOO. BROAD SURFACE HIGH PRESSURE INFLUENCES ALONG WITH BUILDING UPPER LEVEL RIDGING INFLUENCES WILL BE THE MAJOR WX PLAYER THRU THIS PERIOD. DEPENDING ON MODEL LEAN...UPPER LEVEL CLOSED LOW CIRCULATION THAT PREVIOUSLY WAS EXPECTED TO PLAY A ROLE IN BRINGING CONVECTIVE CHANCES TO THE MID STATE PLATEAU WED AFTERNOON AND ON FRI... LOOKS TO DEVELOP BY THE MID PORTION OF NEXT WORK WEEK IN AN UPPER LEVEL TROUGHING PATTERN OVER THE CAROLINA`S AND EITHER EVENTUALLY GO NEWD OF OR SWD OF MID STATE...GENERALLY RESULTING IN NO SIGNIFICANT IMPACTS TO THE MID STATE. MENTION OF ISO SHWRS ON SAT PER POSSIBILITY OF SOME MOISTURE BEING USHERED ACROSS ERN HALF IF CIRCULATION ACTUALLY MOVES NEWD. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 88 63 80 59 / 20 20 10 10 CLARKSVILLE 86 58 78 54 / 30 10 10 10 CROSSVILLE 82 62 77 57 / 10 20 20 10 COLUMBIA 88 62 80 58 / 20 20 10 10 LAWRENCEBURG 87 63 80 59 / 10 10 10 10 WAVERLY 87 59 78 56 / 20 20 10 10 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 31
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
537 AM CDT SAT SEP 19 2015 .UPDATE...FOR 12Z AVIATION DISCUSSION. && .AVIATION UPDATE...12Z AVIATION DISCUSSION. FIGURING IN SUBTLE MODEL DISCREPANCIES ON SFC FRONTAL PASSAGE TIMING... INCLUDING BELOW REFERENCED LIMITED MOISTURE POTENTIAL ALSO... BELIEVE AT BEST TAF SITES WILL EXPERIENCE MAINLY VFR CB CEILINGS WITH VCTS 19/16Z W TO 19/22Z E. ACTUAL CLRING TIMING AMOUNT OF POSSIBLE CEILING EROSION STILL IN QUESTION BEHIND SFC FRONTAL PASSAGE...BUT BELIEVE BECAUSE OF LATE AFTERNOON MIXING POTENTIAL CKV...A TRANSITION TO SCT AC OR SKC CONDITIONS POSSIBLE BY NO LATER THAN 20/03Z. VFR BKN STRATUS CEILINGS SHOULD PERSIST BNA THRU AT LEAST 20/10Z WITH A TRANSITION FROM HIGH END MVFR CEILINGS TO IFR CEILINGS CSV WITH MVFR FOG INDUCED VSBYS POSSIBLY 20/10Z. && .PREV DISCUSSION.../ISSUED 532 AM CDT SAT SEP 19 2015/ UPDATE...FOR 12Z AVIATION DISCUSSION. AVIATION UPDATE...12Z AVIATION DISCUSSION. FIGURING IN SUBTLE MODEL DISCREPANCIES ON SFC FRONTAL PASSAGE TIMING... INCLUDING BELOW REFERENCED LIMITED MOISTURE POTENTIAL ALSO...BELIEVE AT BEST TAF SITES WILL EXPERIENCE MAINLY VFR CB CEILINGS WITH VCTS 19/16Z W TO 19/22Z E. ACTUAL CLRING TIMING AMOUNT OF POSSIBLE CEILING EROSION STILL IN QUESTION BEHIND SFC FRONTAL PASSAGE...BUT BELIEVE BECAUSE OF LATE AFTERNOON MIXING POTENTIAL CKV...A TRANSITION TO SCT AC OR SKC CONDITIONS POSSIBLE BY NO LATER THAN 20/03Z. VFR BKN STRATUS CEILINGS SHOULD PERSIST BNA THRU AT LEAST 20/10Z WITH A TRANSITION FROM HIGH END MVFR CEILINGS TO IFR CEILINGS CSV WITH MVFR FOG INDUCED VSBYS POSSIBLY 20/10Z. PREV DISCUSSION.../ISSUED 354 AM CDT SAT SEP 19 2015/ DISCUSSION... SHORT TERM(TODAY-MON)... COLD FRONT IS CURRENTLY POSITIONED FROM CHI TOWN SW ACROSS NORTHERN TX. UPPER RIDGE AXIS ACROSS THE SOUTHEASTERN U.S. WILL BE SINKING SOUTHWARD AND UPPER LEVEL WESTERLIES SHOULD PREVAIL BY AFTERNOON. THIS WILL ACT TO MOVE THE FRONT OUR WAY. FROPA IS EXPECTED DURING THE LATE AFTERNOON HOURS. MOISTURE AVAILABILITY FOR THE APPROACHING FRONT WILL BE VERY LIMITED. IT DOES APPEAR THAT JUST ENOUGH INSTABILITY WILL RESIDE SO AS TO PROMOTE A LOW 20 POP FOR MOST OF THE AREA FOR TODAY AND THIS EVENING. THE ASSOCIATED UPPER LEVEL DYNAMICS WILL TAKE A NORTHERLY ROUTE...WELL NORTH OF TN. HRRR IS VERY STINGY WITH ANY APPRECIABLE PRECIP WITH THIS SYSTEM. WILL THEREFORE KEEP THE EXPECTED QPF FIELDS ON THE LOW SIDE. AT ANY RATE...CLOUDS WILL INCREASE SLOWLY BETWEEN NOW AND THIS EVENING. MOSTLY CLOUDY SKIES SHOULD PREVAIL FOR TONIGHT AND EARLY SUNDAY. THEN...WE`LL LEAN TOWARD PARTIAL CLOUD COVER. FOR THE NEAR TERM TEMPS...WARM AGAIN FOR TODAY. HIGHS WILL BE WELL INTO THE 80S FOR MOST AREAS. THE COOL DOWN WILL BEGIN TONIGHT AFTER THE FROPA. SUNDAY AND MONDAY WILL FEATURE HIGHS NEAR 80 WEST OF PLATEAU...WITH DEW POINTS IN THE 50S. OVERNIGHT LOWS WILL GENERALLY BE FROM 55 TO 60 FOR SUNDAY NIGHT...ABOUT 5 DEGREES COOLER THAN SAT NT. LONG TERM(TUE-SAT)... DISCREPANCIES BETWEEN MODEL SOLUTIONS STILL REMAIN WITH THIS MORNING`S RUNS...BUT A GENERAL TREND FOR MID TO LATER PORTIONS OF THE WORK WEEK TOWARD A COMPLETELY DRY FORECAST...WITH THE ONLY POTENTIAL OF RAINFALL POSSIBLY THE FIRST PART OF NEXT WEEKEND...AND EVEN THEN ONLY A SLIGHT CHANCE OF SHWRS ACROSS THE ERN HALF OF THE MID STATE. TEMPS WILL GENERALLY BE AROUND OR MAYBE A FEW DEGREES HERE AND THERE ABOVE SEASONAL NORMAL VALUES. MOSTLY CLEAR TO PTCLDY SKIES ARE CONTINUED TO BE EXPECTED THRU THIS PERIOD TOO. BROAD SURFACE HIGH PRESSURE INFLUENCES ALONG WITH BUILDING UPPER LEVEL RIDGING INFLUENCES WILL BE THE MAJOR WX PLAYER THRU THIS PERIOD. DEPENDING ON MODEL LEAN...UPPER LEVEL CLOSED LOW CIRCULATION THAT PREVIOUSLY WAS EXPECTED TO PLAY A ROLE IN BRINGING CONVECTIVE CHANCES TO THE MID STATE PLATEAU WED AFTERNOON AND ON FRI... LOOKS TO DEVELOP BY THE MID PORTION OF NEXT WORK WEEK IN AN UPPER LEVEL TROUGHING PATTERN OVER THE CAROLINA`S AND EITHER EVENTUALLY GO NEWD OF OR SWD OF MID STATE...GENERALLY RESULTING IN NO SIGNIFICANT IMPACTS TO THE MID STATE. MENTION OF ISO SHWRS ON SAT PER POSSIBILITY OF SOME MOISTURE BEING USHERED ACROSS ERN HALF IF CIRCULATION ACTUALLY MOVES NEWD. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 88 63 80 59 / 20 20 10 10 CLARKSVILLE 86 58 78 54 / 30 10 10 10 CROSSVILLE 82 62 77 57 / 10 20 20 10 COLUMBIA 88 62 80 58 / 20 20 10 10 LAWRENCEBURG 87 63 80 59 / 10 10 10 10 WAVERLY 87 59 78 56 / 20 20 10 10 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 31
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
532 AM CDT SAT SEP 19 2015 .UPDATE...FOR 12Z AVIATION DISCUSSION. && .AVIATION UPDATE...12Z AVIATION DISCUSSION. FIGURING IN SUBTLE MODEL DISCREPANCIES ON SFC FRONTAL PASSAGE TIMING... INCLUDING BELOW REFERENCED LIMITED MOISTURE POTENTIAL ALSO...BELIEVE AT BEST TAF SITES WILL EXPERIENCE MAINLY VFR CB CEILINGS WITH VCTS 19/16Z W TO 19/22Z E. ACTUAL CLRING TIMING AMOUNT OF POSSIBLE CEILING EROSION STILL IN QUESTION BEHIND SFC FRONTAL PASSAGE...BUT BELIEVE BECAUSE OF LATE AFTERNOON MIXING POTENTIAL CKV...A TRANSITION TO SCT AC OR SKC CONDITIONS POSSIBLE BY NO LATER THAN 20/03Z. VFR BKN STRATUS CEILINGS SHOULD PERSIST BNA THRU AT LEAST 20/10Z WITH A TRANSITION FROM HIGH END MVFR CEILINGS TO IFR CEILINGS CSV WITH MVFR FOG INDUCED VSBYS POSSIBLY 20/10Z. && .PREV DISCUSSION.../ISSUED 354 AM CDT SAT SEP 19 2015/ DISCUSSION... SHORT TERM(TODAY-MON)... COLD FRONT IS CURRENTLY POSITIONED FROM CHI TOWN SW ACROSS NORTHERN TX. UPPER RIDGE AXIS ACROSS THE SOUTHEASTERN U.S. WILL BE SINKING SOUTHWARD AND UPPER LEVEL WESTERLIES SHOULD PREVAIL BY AFTERNOON. THIS WILL ACT TO MOVE THE FRONT OUR WAY. FROPA IS EXPECTED DURING THE LATE AFTERNOON HOURS. MOISTURE AVAILABILITY FOR THE APPROACHING FRONT WILL BE VERY LIMITED. IT DOES APPEAR THAT JUST ENOUGH INSTABILITY WILL RESIDE SO AS TO PROMOTE A LOW 20 POP FOR MOST OF THE AREA FOR TODAY AND THIS EVENING. THE ASSOCIATED UPPER LEVEL DYNAMICS WILL TAKE A NORTHERLY ROUTE...WELL NORTH OF TN. HRRR IS VERY STINGY WITH ANY APPRECIABLE PRECIP WITH THIS SYSTEM. WILL THEREFORE KEEP THE EXPECTED QPF FIELDS ON THE LOW SIDE. AT ANY RATE...CLOUDS WILL INCREASE SLOWLY BETWEEN NOW AND THIS EVENING. MOSTLY CLOUDY SKIES SHOULD PREVAIL FOR TONIGHT AND EARLY SUNDAY. THEN...WE`LL LEAN TOWARD PARTIAL CLOUD COVER. FOR THE NEAR TERM TEMPS...WARM AGAIN FOR TODAY. HIGHS WILL BE WELL INTO THE 80S FOR MOST AREAS. THE COOL DOWN WILL BEGIN TONIGHT AFTER THE FROPA. SUNDAY AND MONDAY WILL FEATURE HIGHS NEAR 80 WEST OF PLATEAU...WITH DEW POINTS IN THE 50S. OVERNIGHT LOWS WILL GENERALLY BE FROM 55 TO 60 FOR SUNDAY NIGHT...ABOUT 5 DEGREES COOLER THAN SAT NT. LONG TERM(TUE-SAT)... DISCREPANCIES BETWEEN MODEL SOLUTIONS STILL REMAIN WITH THIS MORNING`S RUNS...BUT A GENERAL TREND FOR MID TO LATER PORTIONS OF THE WORK WEEK TOWARD A COMPLETELY DRY FORECAST...WITH THE ONLY POTENTIAL OF RAINFALL POSSIBLY THE FIRST PART OF NEXT WEEKEND...AND EVEN THEN ONLY A SLIGHT CHANCE OF SHWRS ACROSS THE ERN HALF OF THE MID STATE. TEMPS WILL GENERALLY BE AROUND OR MAYBE A FEW DEGREES HERE AND THERE ABOVE SEASONAL NORMAL VALUES. MOSTLY CLEAR TO PTCLDY SKIES ARE CONTINUED TO BE EXPECTED THRU THIS PERIOD TOO. BROAD SURFACE HIGH PRESSURE INFLUENCES ALONG WITH BUILDING UPPER LEVEL RIDGING INFLUENCES WILL BE THE MAJOR WX PLAYER THRU THIS PERIOD. DEPENDING ON MODEL LEAN...UPPER LEVEL CLOSED LOW CIRCULATION THAT PREVIOUSLY WAS EXPECTED TO PLAY A ROLE IN BRINGING CONVECTIVE CHANCES TO THE MID STATE PLATEAU WED AFTERNOON AND ON FRI... LOOKS TO DEVELOP BY THE MID PORTION OF NEXT WORK WEEK IN AN UPPER LEVEL TROUGHING PATTERN OVER THE CAROLINA`S AND EITHER EVENTUALLY GO NEWD OF OR SWD OF MID STATE...GENERALLY RESULTING IN NO SIGNIFICANT IMPACTS TO THE MID STATE. MENTION OF ISO SHWRS ON SAT PER POSSIBILITY OF SOME MOISTURE BEING USHERED ACROSS ERN HALF IF CIRCULATION ACTUALLY MOVES NEWD. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 88 63 80 59 / 20 20 10 10 CLARKSVILLE 86 58 78 54 / 30 10 10 10 CROSSVILLE 82 62 77 57 / 10 20 20 10 COLUMBIA 88 62 80 58 / 20 20 10 10 LAWRENCEBURG 87 63 80 59 / 10 10 10 10 WAVERLY 87 59 78 56 / 20 20 10 10 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 31
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
354 AM CDT SAT SEP 19 2015 .DISCUSSION... .SHORT TERM(TODAY-MON)... COLD FRONT IS CURRENTLY POSITIONED FROM CHI TOWN SW ACROSS NORTHERN TX. UPPER RIDGE AXIS ACROSS THE SOUTHEASTERN U.S. WILL BE SINKING SOUTHWARD AND UPPER LEVEL WESTERLIES SHOULD PREVAIL BY AFTERNOON. THIS WILL ACT TO MOVE THE FRONT OUR WAY. FROPA IS EXPECTED DURING THE LATE AFTERNOON HOURS. MOISTURE AVAILABILITY FOR THE APPROACHING FRONT WILL BE VERY LIMITED. IT DOES APPEAR THAT JUST ENOUGH INSTABILITY WILL RESIDE SO AS TO PROMOTE A LOW 20 POP FOR MOST OF THE AREA FOR TODAY AND THIS EVENING. THE ASSOCIATED UPPER LEVEL DYNAMICS WILL TAKE A NORTHERLY ROUTE...WELL NORTH OF TN. HRRR IS VERY STINGY WITH ANY APPRECIABLE PRECIP WITH THIS SYSTEM. WILL THEREFORE KEEP THE EXPECTED QPF FIELDS ON THE LOW SIDE. AT ANY RATE...CLOUDS WILL INCREASE SLOWLY BETWEEN NOW AND THIS EVENING. MOSTLY CLOUDY SKIES SHOULD PREVAIL FOR TONIGHT AND EARLY SUNDAY. THEN...WE`LL LEAN TOWARD PARTIAL CLOUD COVER. FOR THE NEAR TERM TEMPS...WARM AGAIN FOR TODAY. HIGHS WILL BE WELL INTO THE 80S FOR MOST AREAS. THE COOL DOWN WILL BEGIN TONIGHT AFTER THE FROPA. SUNDAY AND MONDAY WILL FEATURE HIGHS NEAR 80 WEST OF PLATEAU...WITH DEW POINTS IN THE 50S. OVERNIGHT LOWS WILL GENERALLY BE FROM 55 TO 60 FOR SUNDAY NIGHT...ABOUT 5 DEGREES COOLER THAN SAT NT. .LONG TERM(TUE-SAT)... DISCREPANCIES BETWEEN MODEL SOLUTIONS STILL REMAIN WITH THIS MORNING`S RUNS...BUT A GENERAL TREND FOR MID TO LATER PORTIONS OF THE WORK WEEK TOWARD A COMPLETELY DRY FORECAST...WITH THE ONLY POTENTIAL OF RAINFALL POSSIBLY THE FIRST PART OF NEXT WEEKEND...AND EVEN THEN ONLY A SLIGHT CHANCE OF SHWRS ACROSS THE ERN HALF OF THE MID STATE. TEMPS WILL GENERALLY BE AROUND OR MAYBE A FEW DEGREES HERE AND THERE ABOVE SEASONAL NORMAL VALUES. MOSTLY CLEAR TO PTCLDY SKIES ARE CONTINUED TO BE EXPECTED THRU THIS PERIOD TOO. BROAD SURFACE HIGH PRESSURE INFLUENCES ALONG WITH BUILDING UPPER LEVEL RIDGING INFLUENCES WILL BE THE MAJOR WX PLAYER THRU THIS PERIOD. DEPENDING ON MODEL LEAN...UPPER LEVEL CLOSED LOW CIRCULATION THAT PREVIOUSLY WAS EXPECTED TO PLAY A ROLE IN BRINGING CONVECTIVE CHANCES TO THE MID STATE PLATEAU WED AFTERNOON AND ON FRI... LOOKS TO DEVELOP BY THE MID PORTION OF NEXT WORK WEEK IN AN UPPER LEVEL TROUGHING PATTERN OVER THE CAROLINA`S AND EITHER EVENTUALLY GO NEWD OF OR SWD OF MID STATE...GENERALLY RESULTING IN NO SIGNIFICANT IMPACTS TO THE MID STATE. MENTION OF ISO SHWRS ON SAT PER POSSIBILITY OF SOME MOISTURE BEING USHERED ACROSS ERN HALF IF CIRCULATION ACTUALLY MOVES NEWD. .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 88 63 80 59 / 20 20 10 10 CLARKSVILLE 86 58 78 54 / 30 10 10 10 CROSSVILLE 82 62 77 57 / 10 20 20 10 COLUMBIA 88 62 80 58 / 20 20 10 10 LAWRENCEBURG 87 63 80 59 / 10 10 10 10 WAVERLY 87 59 78 56 / 20 20 10 10 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
637 PM CDT SUN SEP 20 2015 .AVIATION... A CLUSTER OF THUNDERSTORMS IS MOVING SOUTH TOWARDS THE KCDS AND TEMPO GROUP IN CURRENT TAF REFLECTS TIME OF ARRIVAL BASED ON CURRENT SPEED AND MOTION. OTHERWISE...VFR CONDITIONS WILL CONTINUE THROUGH EARLY TONIGHT. THERE IS AGAIN A POSSIBILITY OF MVFR CONDITIONS AT ALL THREE TAF SITES EARLY MONDAY MORNING BUT DO NOT EXPECT TO SEE IFR CONDITIONS. CEILINGS WILL GRADUALLY LIFT AFTER SUNRISE WITH VFR CONDITIONS RETURNING SHORTLY BEFORE NOON LOCAL TIME. JORDAN && .PREV DISCUSSION... /ISSUED 330 PM CDT SUN SEP 20 2015/ SHORT TERM... THE CENTER OF THE UA RIDGE REMAINS SOUTH OF THE SOUTH PLAINS AND ROLLING PLAINS LATE THIS AFTN...AND IS AIDING STREAMING A FETCH OF ERN PACIFIC MOISTURE FROM THE BAJA OF CALI TO ACROSS THE SOUTHERN PLAINS. HOWEVER...THE EMERGENCE OF A SLIGHT AMPLIFICATION OF UA RIDGING ACROSS THE SWRN CONUS IS HELPING TO VEER FLOW ALOFT FROM NEAR ZONAL TO THE NW AND AS SUCH...IS SLOWLY SHIFTING THE PLUME OF PACIFIC MOISTURE SWRD WITH TIME. LOOKING AT THE SFC...THANKS TO LAST NIGHTS ADEQUATE LLJ COUPLED WITH WAA...THE ONCE WIDELY SCATTERED SHOWERS FROM EARLIER THIS MORNING HAVE SINCE BECOME LINGERING SHOWERS MORE SO ACROSS THE LOW ROLLING PLAINS LATE THIS AFTN. THE UA RIDGE TO OUR WEST GRADUALLY EXPANDING WRD TOWARDS THE REGION IS HELPING TO FILTER IN DRIER AIR FROM THE TOP DOWN...INITIALLY NOTED ACROSS PORTIONS OF THE WRN...NWRN AND NRN ZONES GIVEN CLEARING SKIES THERE...AND WILL EVENTUALLY FILTER IN TO ACROSS THE SERN ZONES LATER THIS EVENING. SFC TROUGHING/A WARM FRONT DRAPED FROM NW TO SE ACROSS THE ERN TX PANHANDLE TO ACROSS THE NRN ROLLING PLAINS...COMBINED WITH A BIT OF INSOLATION....DETERIORATING CIN AND SB CAPE VALUES OF 1200+ J/KG ACROSS THE AFOREMENTIONED AREAS...RAISES CONCERN FOR A BRIEF PERIOD OF STORMS /POSSIBLY STRONG/ FIRING UP ALONG THE SFC TROUGH LATER THIS AFTN/EARLY THIS EVENING. IN FACT...RADAR TRENDS SHOWED CI OCCURRING ACROSS THE SE TX PANHANDLE NW OF WHEELER TX AS WELL AS SW OF MEMPHIS TX ALONG THAT SFC BOUNDARY. THE TTU WRF MAINTAINS THE CONVECTION NORTH OF THE CWA WHICH APPEARS TO NOT HANDLE THE CURRENT SITUATION. THE HRRR ON THE OTHER-HAND MAY HAVE A BETTER HANDLE ON THE PRECIP SITUATION...AS IT DEVELOPS SCATTERED STORMS ACROSS THE SRN AND SERN TX PANHANDLE WHICH THEN PUSHES SOUTH TO ACROSS THE NERN ZONES LATER THIS AFTN/EARLY EVENING...DESPITE THE MEAN FLOW BEING THE FROM THE W-SW. PERHAPS AN OUTFLOW BOUNDARY/A COLD POOL COULD AID IN THIS SWRD TRAJECTORY. HAVE THEREFORE ELECTED TO INSERT SLIGHT CHANCE POPS ACROSS THE NERN ZONES THIS EVENING THROUGH 21/06Z. TONIGHT...THE PLUME OF PACIFIC MOISTURE WILL HAVE SHIFTED SOUTH OF THE FA...AS THE UA RIDGE CONTINUES TO EXPAND WRD TOWARDS THE REGION. NWRLY FLOW WILL THEREFORE BRIEFLY BECOME ESTABLISHED...HOWEVER RAIN CHANCES LOOK FAIRLY LOW GIVEN THE FILTRATION OF DRIER AIR. IT IS INTERESTING TO NOTE THAT THE NAM SOLUTION IN PARTICULARLY HONES IN THE POTENTIAL OF FOG ESPECIALLY ON THE CAPROCK...AS SFC WINDS GO LIGHT AND VARIABLE AND CLEARING SKIES OCCUR. FURTHERMORE...IT IS LIKELY HANGING ITS HAT ON LAST NIGHT/S AND TODAY/S PRECIP ACTIVITY BEING ENOUGH TO KEEP THE GROUND RATHER SATURATED. THOUGH LOOKING BACK...THE BEST PRECIP /SEVERAL TENTHS OF AN INCH/ FELL ACROSS THE TX PANHANDLE AND PERMIAN BASIN VERSUS SPOTTY AMOUNTS OF A FEW HUNDREDTHS OF AN INCH UP TO PERHAPS A TENTH OF AN INCH ACROSS THE CWA. NOT SURE IF THAT WILL BE ENOUGH TO INITIATE RATHER DENSE FOG AS SHOWN VIA THE NAM /BELOW 1/4 MILE/ BUT PERHAPS LIGHT FOG/HAZE AND/OR FEW LOW CLOUDS ARE NOT TOTALLY OUT OF THE QUESTION. WITH GENERALLY CLEAR SKIES...EXPECT A RELATIVELY COOL NIGHT WITH LOWS IN THE UPPER 50S ACROSS THE SW TX PANHANDLE TO THE MIDDLE 60S ACROSS THE FAR ROLLING PLAINS EXPECTED. HIGHS IN THE LOWER 80S TODAY WILL BE FOLLOWED BY UPPER 80S TO LOWER 90S ON MONDAY...THANKS TO THE UA RIDGE EXPANDING ACROSS THE REGION AND THUS...AN UPTICK IN 500 MB HEIGHT FIELDS AND 850 MB TEMPS OCCUR. DRY CONDITIONS ARE EXPECTED. LONG TERM... AN UPPER LEVEL HIGH PRESSURE RIDGE WILL AMPLIFY ACROSS OUR AREA EARLY IN THE WEEK. A DISTURBANCE ALONG THE WEST COAST OF MEXICO WILL LIFT NORTHWARD INTO THE SOUTHERN ROCKIES WITH MOISTURE IMPROVEMENT OVER THE SOUTHERN HIGH PLAINS AS WELL. THE BULK OF LIFT AND INSTABILITY IS EXPECTED TO REMAIN TO OUR WEST. WE WILL HOLD ON TO SMALL THUNDER MENTION ALONG OUR WESTERN BORDER AREAS TUESDAY. QUICKLY FOLLOWING WILL BE THE OLD CLOSED UPPER LOW OFF BAJA THAT MODELS HAVE BEEN SPEEDING UP AND MAINTAINING MORE INTENSITY THROUGH THE CENTRAL ROCKIES INTO THE CENTRAL HIGH PLAINS. HEIGHTS ALOFT SHOULD FALL OVER OUR AREA TUESDAY NIGHT AND WEDNESDAY WITH DEEPER MOISTURE DRAGGING ACROSS NORTHWEST AND NORTHERN ZONES INITIALLY AS UPPER RIDGE RETREATS SOUTH AND WEST EVENTUALLY TO REFORM FURTHER WEST OVER THE SOUTHERN PLATEAU AND NORTHWEST MEXICO. MOISTURE SHOULD CONTINUE ACROSS THE AREA THURSDAY THOUGH WITHOUT SIGNIFICANT LIFT...STILL VALID FOR A LOW MENTION OF THUNDER ACROSS MUCH OF THE AREA. AS THE UPPER RIDGE REFORMS TO THE WEST ON FRIDAY...THIS MAY OPEN A WINDOW FOR THE REMNANTS OF THE CENTRAL HIGH PLAINS LOW TO DIP BACK SOUTHWARD. OUR SOLUTIONS ARE NOT AT ALL CONSISTENT ON THIS AND WE WILL RETAIN DRY FORECAST HEADING INTO NEXT WEEKEND...BUT GIVES SOMETHING TO WATCH IN THAT FAR EXTENDED TIME FRAME. AFTER AN INITIAL COUPLE OR THREE FAIRLY WARM DAYS THIS WEEK...THE COMBINATION OF IMPROVED MOISTURE AND LOWER HEIGHTS WITH LESS UPPER RIDGE INFLUENCE CONTINUE TO FAVOR ABOVE NORMAL ALTHOUGH MORE MODERATE TEMPERATURES LATE WEEK INTO THE NEXT WEEKEND. RMCQUEEN && .PRELIMINARY POINT TEMPS/POPS... FRIONA 59 88 61 83 / 0 0 0 20 TULIA 60 88 61 86 / 10 0 0 10 PLAINVIEW 60 88 60 87 / 10 0 0 10 LEVELLAND 60 87 61 86 / 0 0 0 10 LUBBOCK 60 89 63 88 / 10 0 0 10 DENVER CITY 60 87 61 85 / 0 0 10 10 BROWNFIELD 61 87 62 86 / 10 0 0 10 CHILDRESS 65 92 67 94 / 20 0 0 0 SPUR 63 90 65 91 / 10 0 0 0 ASPERMONT 65 94 68 94 / 10 0 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 14/93/14
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1258 PM CDT SAT SEP 19 2015 .AVIATION... /18Z TAFS/ COLD FRONT HAS MOVED THROUGH MOST OF THE MAJOR AIRPORTS SO FAR THIS AFTERNOON WITH THE EXCEPTION OF WACO...ALTHOUGH THE FRONT IS NOT VERY STRONG AND THE BOUNDARY MAY ACTUALLY WOBBLE A BIT THROUGH THE EARLY AFTERNOON. NORTHERLY FLOW DOES PREVAIL AT THIS TIME IN THE METROPLEX AND THAT SHOULD REMAIN THROUGH TONIGHT. MOST OF THE EARLIER CONVECTION HAS WEAKENED SUBSTANTIALLY OVER THE LAST 2 HOURS BUT THERE IS STILL AN AREA OF RAIN THAT EXTENDS FROM DFW NORTHEAST TO PARIS. NEW CONVECTION HAS BEGUN TO DEVELOP SOUTHWEST OF THE METROPLEX IN MORE UNSTABLE AIR ALONG THE FRONTAL BOUNDARY. THIS WILL LIKELY BE WHERE MOST OF THE CONVECTIVE ACTIVITY WILL BE THROUGH THIS AFTERNOON. AT THIS TIME...WILL PREVAIL VFR CONDITIONS AT THE MAJOR AIRPORTS ALTHOUGH THERE ARE SOME MVFR CIGS JUST TO THE NORTHWEST. THINKING IS THAT THESE WILL SCATTER OUT THROUGH THE AFTERNOON. WINDS ARE EXPECTED TO BE NORTH/NORTHEAST THROUGH THIS EVENING THEN BECOME LGT/VAR OVERNIGHT. THE FRONT IS NOT EXPECTED TO MAKE IT THROUGH WACO AT THIS TIME...SO WILL KEEP SOUTHERLY FLOW IN PLACE THERE. DUNN && .UPDATE... BASED ON CURRENT RADAR TRENDS...HAVE UPDATED POPS FOR TODAY TO ACCOUNT FOR THE MORE WIDESPREAD COVERAGE OF SHOWERS AND STORMS IN THE NORTHEAST ZONES AND MORE SCATTERED COVERAGE OUT WEST. EXPECT THE COLD FRONT TO STALL AND BECOME LESS DEFINED THIS AFTERNOON...BUT SCATTERED SHOWERS AND STORMS WILL STILL BE POSSIBLE NEAR THIS BOUNDARY AS THE DAY PROGRESSES. AJS && .PREV DISCUSSION... /ISSUED 240 AM CDT SAT SEP 19 2015/ THE COLD FRONT WAS LOCATED ALONG A LINE FROM FORT SMITH TO SOUTH OF LUBBOCK AT 07Z/2AM AND MOVING SOUTHEAST NEAR 18 MPH. AN OUTFLOW BOUNDARY AHEAD OF CONVECTION ALONG/BEHIND THE FRONT WILL WORK THROUGH THE NORTHWEST HALF OF THE CWA THIS MORNING WITH CONVECTION SPREADING SOUTHEASTWARD AS WELL. THE HRRR AND TT WRF SPREAD CONVECTION INTO THE NORTHWEST HALF OF THE DFW METROPLEX 10-12Z SO HAVE MAINTAINED CHANCE POPS OVER THE NORTHWEST HALF TODAY. THE FRONT WILL LIKELY MOVE TO NEAR A PALESTINE TO GOLDTHWAITE LINE BY MIDNIGHT TONIGHT...THEN DRIFT NORTHWARD A LITTLE EARLY SUNDAY AND STALL OUT JUST SOUTH OF I-20 DURING THE DAY WITH THE BEST CHANCE OF CONVECTION GENERALLY NORTH OF THE FRONT. THE WEST END OF THE FRONT LIFTS NORTHWARD ON SUNDAY NIGHT AND THEN THE ENTIRE FRONT LIFTS OUT NORTHEAST ON MONDAY. SUNDAY NIGHT POPS WILL SHIFT TO THE NORTHEAST COUNTIES AND MONDAY POPS WILL BE MAINLY OVER THE FAR EASTERN COUNTIES. SOME STRONG THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING DUE TO A FAIR AMOUNT OF INSTABILITY ALONG THE FRONT....AND LOCALIZED HEAVY RAINFALL IS ALSO POSSIBLE DUE TO PWATS NEAR/AROUND 2 INCHES. HIGH TEMPERATURES TODAY WILL NOT CHANGE AHEAD OF THE FRONT BUT THEY WILL BE 5-10 DEGREES COOLER BEHIND IT. AS THE FRONT BECOMES DIFFUSED ON SUNDAY AND LIFTS OUT ON MONDAY...HIGH TEMPS WILL CREEP UPWARD WITH MOST OF THE CWA BACK IN THE LOWER TO MID 90S TUESDAY THROUGH FRIDAY. HAVE ADJUSTED OVERNIGHT LOWS DOWN 1-3 DEGREES...MAINLY RURAL AREAS...THURSDAY AND FRIDAY DUE TO DRIER AIR SPREADING INTO THE REGION. LOOKING AHEAD INTO NEXT WEEKEND AND THE LAST WEEK OF SEPTEMBER...BOTH THE GFS AND ECMWF MODELS ARE INDICATING A WEAKNESS ALOFT OVER THE SOUTHEAST OR SOUTHERN STATES AND THE UPPER RIDGE OFF TO OUR WEST. THIS PATTERN WOULD RESULT IN LOWER HEIGHTS ALOFT OVER NORTH AND CENTRAL TEXAS...AND THUS TEMPERATURES A LITTLE CLOSER TO NORMAL WITH HIGHS IN THE MID 80S TO LOWER 90S. 75 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 88 72 90 72 92 / 40 30 20 10 5 WACO, TX 93 70 95 71 93 / 10 10 10 5 5 PARIS, TX 87 67 87 66 87 / 50 20 30 30 20 DENTON, TX 87 69 89 68 91 / 50 40 20 20 5 MCKINNEY, TX 88 69 90 69 90 / 50 30 20 20 10 DALLAS, TX 89 73 90 71 92 / 40 30 20 10 5 TERRELL, TX 91 69 91 69 91 / 30 20 20 20 10 CORSICANA, TX 94 71 93 71 92 / 10 10 10 5 10 TEMPLE, TX 93 69 93 70 92 / 10 10 5 5 5 MINERAL WELLS, TX 87 67 90 68 91 / 40 40 20 10 5 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1244 PM CDT SAT SEP 19 2015 .DISCUSSION...UPDATED FOR LATEST /18Z/ AVIATION DISCUSSION BELOW. && .AVIATION...ASIDE FROM THE FIRST FEW HOURS OF THE FORECAST...STRAIGHTFORWARD SITUATION UPCOMING THROUGH MIDDAY SUNDAY. EVEN WITH VERY DRY AIR ALOFT...THERE WAS ENOUGH MOISTURE THROUGH 700 MB (WHICH SEEMS TO BE THE MAGIC FORMULA SOMETIMES) FOR SCATTERED BUT LOCALLY HEAVY SHOWERS NEARBY AND OVER KBRO AND KHRL. UNLIKE RECENT DAYS...LOW LEVEL FLOW HAS SLACKENED AND CELLS NOT MOVING ALL THAT MUCH WITH A SLOW WESTWARD DRIFT. SO...HAVE KEPT MVFR VISIBILITY RAIN AT KBRO THROUGH 3 PM AND ADDED A TEMPO GROUP FOR KHRL FOR THE DEVELOPMENT ALL AROUND THEM. WILL KEEP A CLOSE EYE FOR THUNDER AND IFR VISIBILITY ALONG WITH MVFR CEILINGS AND MAY HAVE TO AMEND AT KHRL. FOR KMFE...DRY AIR DOMINATES AND WITH LITTLE WESTWARD MOTION TODAY HAVE LEFT MENTIONABLE RAIN/VISIBILITY RESTRICTIONS OUT OF THE FORECAST. AFTER THE ACTIVITY CALMS DOWN...SKIES RETURN TO FEW-SCATTERED VFR CUMULUS AND THE USUAL 10-15 KNOT EASTERLY SEA BREEZE ENHANCEMENT WILL SPREAD FROM KHRL/KBRO TO KMFE BY 4-5 PM OR SO. SKIES SHOULD CLEAR OVERNIGHT AND WINDS DROP TOWARD CALM...WITH FAIR WEATHER HIGH MVFR/LOW VFR SCATTERED CUMULUS BY 14/15Z SUNDAY. ATMOSPHERE LOOKS A TAD DRIER SUNDAY SO HAVE LEFT OUT RAIN MENTION AFTER 16Z BUT MAY NEED TO REVIEW WITH LATER FORECASTS. 52/BSG && .PREV DISCUSSION... /ISSUED 633 AM CDT SAT SEP 19 2015/ DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW. AVIATION...GENERAL VFR CONDITIONS TO PREVAIL ACROSS THE RIO GRANDE VALLEY AND MUCH OF DEEP SOUTH TEXAS TODAY AND TONIGHT WITH STRONG HIGH PRESSURE RESIDING OVER TEXAS. ONCE AGAIN PATCHY GROUND FOG MAY DEVELOP PRODUCING MVFR VSBY FOR AN HOUR OR LESS THIS MORNING WITH LATEST OBSERVATIONS SHOWING CONDITIONS NOT THAT CONDUCIVE FOR FOG FORMATION. WITH THE FOG HAVING A DIFFICULT TIME FORMING THIS MORNING WILL ONLY MENTION TEMPS CONDITIONS FOR AN HOUR AT KHRL AND KMFE. A FEW SHOWERS LINGER ALONG AND JUST EAST OF THE LOWER TEXAS COAST BUT REMAIN FAR REMOVED FROM THE 3 TERMINALS SITES. A WEAK SEA BREEZE MOVES INLAND TODAY AND MAY SPARK AN ISOLATED SHOWER BUT THE WIDE DISTRIBUTION OF THE SHOWERS SHOULD NOT IMPACT THE TERMINALS AND NO SHWR OR RAIN IS MENTIONED IN THE LATEST TAFS. A LIGHT SOUTHEAST TO EAST WIND TO PREVAIL. PREV DISCUSSION... /ISSUED 401 AM CDT SAT SEP 19 2015/ SHORT TERM /TODAY THROUGH SUNDAY/...500 MB RIDGE WELL ESTABLISHED OVER TEXAS WITH A VERY DRY 700-300MB LAYER IN PLACE ACROSS SOUTH TEXAS. MEAN RH WITHIN THIS LAYER IS BELOW 10 PERCENT WITH THE LOWER 10K FEET STILL EXHIBITING THE TYPICAL RH LEVELS OF 50 TO 80 PERCENT. TIME HEIGHT FORECAST INDICATE SLIGHTLY HIGHER RH LEVELS IN THE LOWER LAYER OVER THE MID RIO GRANDE VALLEY. LIGHT EASTERLY FLOW AND THERMAL GRADIENT TO INITIALIZE A SEA BREEZE THIS AFTERNOON WHICH WILL COMBINE WITH THE SLIGHTLY HIGHER MOISTURE CONTENT TO PRODUCE AN ISOLATED SHOWER OR TWO SOME WHERE BETWEEN INTERSTATE HIGHWAYS 69E AND 69C LATE THIS MORNING AND AFTERNOON. IF THE DRIER MID LEVEL AIR MIXES THROUGH THE LOWER LAYER QUICKER THAN EXPECTED CONVECTION WILL BE VERY DIFFICULT TO DEVELOP AND THE SLIGHT CHANCES WILL EVAPORATE QUICKLY. THE DRY AIR MASS TO REMAIN IN PLACE TONIGHT AND SUNDAY WITH PWAT VALUES LOWERING WELL BELOW MID SEPTEMBER NORMALS WHICH WILL MAINTAIN A RELATIVELY DRY FORECAST. HIGH TEMPERATURES RANGED 3 TO 5 DEGREES ABOVE NORMAL YESTERDAY AND MODEL GUIDANCE CONTINUES TO INDICATED THIS TREND TODAY AND SUNDAY. LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...LOW TO MID LEVEL MOISTURE WILL BE LIMITED ACROSS SOUTH TEXAS SUNDAY AS THE 500MB RIDGE ACROSS NORTHERN MEXICO AND THE WESTERN GULF OF MEXICO CONTINUES TO PROVIDE SUBSIDENCE ACROSS THE AREA. A 500MB TROUGH ACROSS THE EASTERN U.S. ALLOWS THE UPPER LEVEL RIDGE TO SHIFT SLIGHTLY WESTWARD AND AMPLIFY ACROSS THE SOUTH CENTRAL U.S. MONDAY INTO TUESDAY. NORTHERLY FLOW ALOFT WILL CONTINUE TO PROVIDE SUBSIDENCE ACROSS THE AREA. A WEAK COLD FRONT IS EXPECTED TO MOVE ACROSS THE SOUTHEAST U.S. MONDAY INTO TUESDAY BUT THE FRONT IS NOT EXPECTED TO MOVE THROUGH SOUTH TX. THE UPPER LEVEL PATTERN IS PROGGED TO REMAIN SUBSIDENT ACROSS THE STATE THROUGH THE REST OF THE FORECAST PERIOD WITH A 500MB LOW CUTTING OFF FROM THE UPPER LEVEL TROUGH ACROSS THE EASTERN U.S. WEDNESDAY INTO THURSDAY AND THE UPPER LEVEL RIDGE ACROSS THE SOUTH CENTRAL U.S. RETROGRADES WESTWARD ACROSS THE SOUTHWEST U.S. AND AMPLIFIES. WILL CONTINUE NOT TO MENTION RAIN CHANCES THROUGH FRIDAY WITH WARM AND RELATIVELY DRY CONDITIONS PREVAILING THROUGH THE REST OF THE WEEK. MARINE... TODAY THROUGH SUNDAY...WEAK SURFACE HIGH PRESSURE TO RESIDE OVER THE NORTHWEST GULF TODAY SPREADING EASTWARD SUNDAY. LIGHT EAST TO SOUTHEAST WINDS AND A SLOW SUBSIDING SEA IS EXPECTED. SUNDAY NIGHT THROUGH WEDNESDAY...LIGHT EAST TO SOUTHEAST WINDS WILL PREVAIL ACROSS THE COASTAL WATERS SUN NIGHT INTO MONDAY AS A WEAK COLD FRONT MOVES ACROSS THE SOUTHEAST UNITED STATES AND STALLS. THE PRESSURE GRADIENT IS EXPECTED TO REMAIN WEAK ACROSS THE WESTERN GULF OF MEXICO TUESDAY WITH HIGH PRESSURE ACROSS THE EASTERN UNITED STATES. LIGHT EAST TO SOUTHEAST WINDS WILL PREVAIL ACROSS THE LOWER TEXAS COAST TUESDAY AND WEDNESDAY. && .BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV
Area Forecast Discussion National Weather Service Midland/Odessa TX 1241 PM CDT SAT SEP 19 2015 .AVIATION... 18Z TAF issuance. The main aviation concern for the next 24 hours is thunderstorms affecting terminals this afternoon/evening and potentially overnight. Currently have a cold front located near the Pecos River Valley with NE winds and SCT-BKN low cigs to the north of this boundary. Low cigs continue to affect CNM/HOB/MAF but clouds will scatter out shortly over most areas. Showers and storms moving north across far west this morning will continue to move north and potentially affect CNM in the next couple hours. In addition, should see TS activity increase near the front later this afternoon but confidence in timing and specific locations is low, therefore just mentioned TSRA in a TEMPO for a few hours this afternoon at all terminals. Some forecast models indicate thunderstorms lasting well into the night and potentially through early Sunday morning. For now, will hold off on any mention of thunder beyond this evening. Will continue to monitor current radar/satellite trends and amend when needed. Otherwise, VFR conditions are expected to prevail except where TSRA may result in brief periods of low vis. && PREV DISCUSSION... /issued 423 AM CDT SAT SEP 19 2015/ DISCUSSION...As of 4:00 AM CDT Saturday...a brief respite from the heat this weekend. Sfc obs and KMAF radar is indc that a cold front is currently over the Central Permian Basin. A few small thunderstorms are popping up behind the front. There are also a few thunderstorms along the Rio Grande in Northwest Presidio County along the edge of a large MCS centered over portions of Sonora and Chihuahua Mexico. The HRRR and RAP13 hi-res models move the cold front slowly south this morning...stalling near or north of I-10 this aftn. With good low-level convergence and weak mid level impulses the hi-res models bring a good shot of convection along the I-20 corridor this morning...moving south this aftn. The main impacts from the thunderstorms will be locally heavy rain and gusty winds. With the rain potential and cloud cover it will be significantly cooler than yesterday...in fact today should be the coolest day this month. Have continued convective chances tonight with the front over the CWA. The cold front will retreat north/wash out on Sunday as a ridge builds back into the Southern Plains/Rockies. Temps will warm to near seasonal levels on Sunday with a slight chance of thunderstorms. A blocking pattern develops over the CONUS next week with a trough along both coasts and a ridge over the Central US. Shortwaves will ride over the ridge...occasionally flattening it slightly. The Davis Mtns...and even more so the Guadalupe Mtns will be on the eastern edge of any convective activity into mid week. Otherwise...the rest of the CWA will be dry. Even though the center of the H85 thermal ridge will be just west of the CWA expect temps next week to be 5-10 degrees above normal...with widespread low 90s and even a few mid 90s across the lower elevations. Widespread 80s are expected in the Mtns...with upper 80s along the extreme northern portions of the CWA. The latest GFS ensemble forecasts keeps West Texas/Southeast New Mexico dry with above normal temperatures through the end of September and into the first several days of October. Strobin MAF WATCHES/WARNINGS/ADVISORIES... NM...NONE. TX...NONE. && .MAF WATCHES/WARNINGS/ADVISORIES... NM...NONE. TX...NONE. && $$ 27
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1002 AM CDT SAT SEP 19 2015 .UPDATE... BASED ON CURRENT RADAR TRENDS...HAVE UPDATED POPS FOR TODAY TO ACCOUNT FOR THE MORE WIDESPREAD COVERAGE OF SHOWERS AND STORMS IN THE NORTHEAST ZONES AND MORE SCATTERED COVERAGE OUT WEST. EXPECT THE COLD FRONT TO STALL AND BECOME LESS DEFINED THIS AFTERNOON...BUT SCATTERED SHOWERS AND STORMS WILL STILL BE POSSIBLE NEAR THIS BOUNDARY AS THE DAY PROGRESSES. AJS && .AVIATION... /ISSUED 714 AM CDT SAT SEP 19 2015/ /12Z TAFS/ DIFFUSE COLD FRONT EXTENDS FROM NEAR FT SMITH TO SHERMAN TO ABILENE AT 12Z. ZONAL FLOW ALOFT AND THE LACK OF A STRONG THUNDERSTORM-INDUCED COLD POOL OVER WRN OK HAS LIMITED THE SOUTHWARD PROGRESSION OF THIS BOUNDARY OVERNIGHT. NEVERTHELESS... THE FRONT SHOULD HAVE ENOUGH VIGOR TO PRESS ONWARD INTO THE INTERSTATE 20 CORRIDOR BY LATE MORNING...REACHING A CORSICANA- GOLDTHWAITE LINE BY 06Z TONIGHT. ONE OR MORE WEAK SURFACE OUTFLOW BOUNDARIES...ARISING FROM THE EARLY MORNING CONVECTION NW OF THE METROPLEX...SHOULD MOVE ACROSS THE DFW-AREA TAF SITES IN THE 12-14Z TIMEFRAME....TEMPORARILY VEERING WINDS AT SOME LOCATIONS TO A LIGHT WEST/NW DIRECTION. THE MAIN FRONT ITSELF SHOULD CLEAR ALL OF THESE TAF SITES BY 15-16Z...PRODUCING SUSTAINED N TO NE FLOW FROM LATE MORNING ONWARD THROUGH TONIGHT. ISOLATED TO SCATTERED SHOWERS HAVE ALREADY REACHED THE I-35 CORRIDOR AS OF 12Z...AND CONVERGENCE ALONG THE FRONT/OUTFLOW BOUNDARIES SHOULD BE SUFFICIENT TO MAINTAIN SCATTERED CONVECTIVE ACTIVITY ACROSS THE DFW AREA THROUGH 22Z. THROUGH 16Z THIS MORNING...THUNDERSTORM ACTIVITY SHOULD BE VERY ISOLATED. AS DAYTIME HEATING ENSUES...SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP ANYWHERE NORTH OF I-20 IN THE 16-22Z WINDOW. CEILINGS AND VISIBILITIES AT THE METROPLEX TAF SITES SHOULD REMAIN VFR TODAY...HOWEVER...EVEN IN AREAS THAT EXPERIENCE SHOWER ACTIVITY. THE FRONT SHOULD REMAIN JUST NORTH OF WACO THROUGH MOST OF TODAY...BUT CLOSE ENOUGH TO NUDGE SOUTHERLY WINDS BACK TO A SE- EAST DIRECTION AFTER 22Z. ISOLATED SHOWERS OR THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON NEAR WACO...BUT THE THREAT IS SUFFICIENTLY LOW TO PRECLUDE MENTION IN THE 12Z TAF. VFR CONDITIONS SHOULD PREVAIL AT WACO THROUGH TONIGHT. BRADSHAW && .PREV DISCUSSION... /ISSUED 240 AM CDT SAT SEP 19 2015/ THE COLD FRONT WAS LOCATED ALONG A LINE FROM FORT SMITH TO SOUTH OF LUBBOCK AT 07Z/2AM AND MOVING SOUTHEAST NEAR 18 MPH. AN OUTFLOW BOUNDARY AHEAD OF CONVECTION ALONG/BEHIND THE FRONT WILL WORK THROUGH THE NORTHWEST HALF OF THE CWA THIS MORNING WITH CONVECTION SPREADING SOUTHEASTWARD AS WELL. THE HRRR AND TT WRF SPREAD CONVECTION INTO THE NORTHWEST HALF OF THE DFW METROPLEX 10-12Z SO HAVE MAINTAINED CHANCE POPS OVER THE NORTHWEST HALF TODAY. THE FRONT WILL LIKELY MOVE TO NEAR A PALESTINE TO GOLDTHWAITE LINE BY MIDNIGHT TONIGHT...THEN DRIFT NORTHWARD A LITTLE EARLY SUNDAY AND STALL OUT JUST SOUTH OF I-20 DURING THE DAY WITH THE BEST CHANCE OF CONVECTION GENERALLY NORTH OF THE FRONT. THE WEST END OF THE FRONT LIFTS NORTHWARD ON SUNDAY NIGHT AND THEN THE ENTIRE FRONT LIFTS OUT NORTHEAST ON MONDAY. SUNDAY NIGHT POPS WILL SHIFT TO THE NORTHEAST COUNTIES AND MONDAY POPS WILL BE MAINLY OVER THE FAR EASTERN COUNTIES. SOME STRONG THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING DUE TO A FAIR AMOUNT OF INSTABILITY ALONG THE FRONT....AND LOCALIZED HEAVY RAINFALL IS ALSO POSSIBLE DUE TO PWATS NEAR/AROUND 2 INCHES. HIGH TEMPERATURES TODAY WILL NOT CHANGE AHEAD OF THE FRONT BUT THEY WILL BE 5-10 DEGREES COOLER BEHIND IT. AS THE FRONT BECOMES DIFFUSED ON SUNDAY AND LIFTS OUT ON MONDAY...HIGH TEMPS WILL CREEP UPWARD WITH MOST OF THE CWA BACK IN THE LOWER TO MID 90S TUESDAY THROUGH FRIDAY. HAVE ADJUSTED OVERNIGHT LOWS DOWN 1-3 DEGREES...MAINLY RURAL AREAS...THURSDAY AND FRIDAY DUE TO DRIER AIR SPREADING INTO THE REGION. LOOKING AHEAD INTO NEXT WEEKEND AND THE LAST WEEK OF SEPTEMBER...BOTH THE GFS AND ECMWF MODELS ARE INDICATING A WEAKNESS ALOFT OVER THE SOUTHEAST OR SOUTHERN STATES AND THE UPPER RIDGE OFF TO OUR WEST. THIS PATTERN WOULD RESULT IN LOWER HEIGHTS ALOFT OVER NORTH AND CENTRAL TEXAS...AND THUS TEMPERATURES A LITTLE CLOSER TO NORMAL WITH HIGHS IN THE MID 80S TO LOWER 90S. 75 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 88 72 90 72 92 / 40 30 20 10 5 WACO, TX 93 70 95 71 93 / 10 10 10 5 5 PARIS, TX 87 67 87 66 87 / 50 20 30 30 20 DENTON, TX 87 69 89 68 91 / 50 40 20 20 5 MCKINNEY, TX 88 69 90 69 90 / 50 30 20 20 10 DALLAS, TX 89 73 90 71 92 / 40 30 20 10 5 TERRELL, TX 91 69 91 69 91 / 30 20 20 20 10 CORSICANA, TX 94 71 93 71 92 / 10 10 10 5 10 TEMPLE, TX 93 69 93 70 92 / 10 10 5 5 5 MINERAL WELLS, TX 87 67 90 68 91 / 40 40 20 10 5 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
714 AM CDT SAT SEP 19 2015 .AVIATION... /12Z TAFS/ DIFFUSE COLD FRONT EXTENDS FROM NEAR FT SMITH TO SHERMAN TO ABILENE AT 12Z. ZONAL FLOW ALOFT AND THE LACK OF A STRONG THUNDERSTORM-INDUCED COLD POOL OVER WRN OK HAS LIMITED THE SOUTHWARD PROGRESSION OF THIS BOUNDARY OVERNIGHT. NEVERTHELESS... THE FRONT SHOULD HAVE ENOUGH VIGOR TO PRESS ONWARD INTO THE INTERSTATE 20 CORRIDOR BY LATE MORNING...REACHING A CORSICANA- GOLDTHWAITE LINE BY 06Z TONIGHT. ONE OR MORE WEAK SURFACE OUTFLOW BOUNDARIES...ARISING FROM THE EARLY MORNING CONVECTION NW OF THE METROPLEX...SHOULD MOVE ACROSS THE DFW-AREA TAF SITES IN THE 12-14Z TIMEFRAME....TEMPORARILY VEERING WINDS AT SOME LOCATIONS TO A LIGHT WEST/NW DIRECTION. THE MAIN FRONT ITSELF SHOULD CLEAR ALL OF THESE TAF SITES BY 15-16Z...PRODUCING SUSTAINED N TO NE FLOW FROM LATE MORNING ONWARD THROUGH TONIGHT. ISOLATED TO SCATTERED SHOWERS HAVE ALREADY REACHED THE I-35 CORRIDOR AS OF 12Z...AND CONVERGENCE ALONG THE FRONT/OUTFLOW BOUNDARIES SHOULD BE SUFFICIENT TO MAINTAIN SCATTERED CONVECTIVE ACTIVITY ACROSS THE DFW AREA THROUGH 22Z. THROUGH 16Z THIS MORNING...THUNDERSTORM ACTIVITY SHOULD BE VERY ISOLATED. AS DAYTIME HEATING ENSUES...SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP ANYWHERE NORTH OF I-20 IN THE 16-22Z WINDOW. CEILINGS AND VISIBILITIES AT THE METROPLEX TAF SITES SHOULD REMAIN VFR TODAY...HOWEVER...EVEN IN AREAS THAT EXPERIENCE SHOWER ACTIVITY. THE FRONT SHOULD REMAIN JUST NORTH OF WACO THROUGH MOST OF TODAY...BUT CLOSE ENOUGH TO NUDGE SOUTHERLY WINDS BACK TO A SE- EAST DIRECTION AFTER 22Z. ISOLATED SHOWERS OR THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON NEAR WACO...BUT THE THREAT IS SUFFICIENTLY LOW TO PRECLUDE MENTION IN THE 12Z TAF. VFR CONDITIONS SHOULD PREVAIL AT WACO THROUGH TONIGHT. BRADSHAW && .PREV DISCUSSION... /ISSUED 240 AM CDT SAT SEP 19 2015/ THE COLD FRONT WAS LOCATED ALONG A LINE FROM FORT SMITH TO SOUTH OF LUBBOCK AT 07Z/2AM AND MOVING SOUTHEAST NEAR 18 MPH. AN OUTFLOW BOUNDARY AHEAD OF CONVECTION ALONG/BEHIND THE FRONT WILL WORK THROUGH THE NORTHWEST HALF OF THE CWA THIS MORNING WITH CONVECTION SPREADING SOUTHEASTWARD AS WELL. THE HRRR AND TT WRF SPREAD CONVECTION INTO THE NORTHWEST HALF OF THE DFW METROPLEX 10-12Z SO HAVE MAINTAINED CHANCE POPS OVER THE NORTHWEST HALF TODAY. THE FRONT WILL LIKELY MOVE TO NEAR A PALESTINE TO GOLDTHWAITE LINE BY MIDNIGHT TONIGHT...THEN DRIFT NORTHWARD A LITTLE EARLY SUNDAY AND STALL OUT JUST SOUTH OF I-20 DURING THE DAY WITH THE BEST CHANCE OF CONVECTION GENERALLY NORTH OF THE FRONT. THE WEST END OF THE FRONT LIFTS NORTHWARD ON SUNDAY NIGHT AND THEN THE ENTIRE FRONT LIFTS OUT NORTHEAST ON MONDAY. SUNDAY NIGHT POPS WILL SHIFT TO THE NORTHEAST COUNTIES AND MONDAY POPS WILL BE MAINLY OVER THE FAR EASTERN COUNTIES. SOME STRONG THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING DUE TO A FAIR AMOUNT OF INSTABILITY ALONG THE FRONT....AND LOCALIZED HEAVY RAINFALL IS ALSO POSSIBLE DUE TO PWATS NEAR/AROUND 2 INCHES. HIGH TEMPERATURES TODAY WILL NOT CHANGE AHEAD OF THE FRONT BUT THEY WILL BE 5-10 DEGREES COOLER BEHIND IT. AS THE FRONT BECOMES DIFFUSED ON SUNDAY AND LIFTS OUT ON MONDAY...HIGH TEMPS WILL CREEP UPWARD WITH MOST OF THE CWA BACK IN THE LOWER TO MID 90S TUESDAY THROUGH FRIDAY. HAVE ADJUSTED OVERNIGHT LOWS DOWN 1-3 DEGREES...MAINLY RURAL AREAS...THURSDAY AND FRIDAY DUE TO DRIER AIR SPREADING INTO THE REGION. LOOKING AHEAD INTO NEXT WEEKEND AND THE LAST WEEK OF SEPTEMBER...BOTH THE GFS AND ECMWF MODELS ARE INDICATING A WEAKNESS ALOFT OVER THE SOUTHEAST OR SOUTHERN STATES AND THE UPPER RIDGE OFF TO OUR WEST. THIS PATTERN WOULD RESULT IN LOWER HEIGHTS ALOFT OVER NORTH AND CENTRAL TEXAS...AND THUS TEMPERATURES A LITTLE CLOSER TO NORMAL WITH HIGHS IN THE MID 80S TO LOWER 90S. 75 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 88 72 90 72 92 / 40 30 20 10 5 WACO, TX 93 70 95 71 93 / 20 10 10 5 5 PARIS, TX 87 67 87 66 87 / 30 20 30 30 20 DENTON, TX 87 69 89 68 91 / 40 40 20 20 5 MCKINNEY, TX 88 69 90 69 90 / 40 30 20 20 10 DALLAS, TX 89 73 90 71 92 / 40 30 20 10 5 TERRELL, TX 91 69 91 69 91 / 20 20 20 20 10 CORSICANA, TX 94 71 93 71 92 / 10 10 10 5 10 TEMPLE, TX 93 69 93 70 92 / 10 10 5 5 5 MINERAL WELLS, TX 87 67 90 68 91 / 40 40 20 10 5 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
641 AM CDT SAT SEP 19 2015 .AVIATION... LOW CLOUDS HAVE FILLED IN BEHIND LAST NIGHT/S FROPA AND THEY WILL LIKELY STICK AROUND THROUGH MUCH OF THE DAY TODAY. MVFR CIGS SHOULD BE THE RULE AT KLBB AND KPVW...THOUGH KCDS WILL BE MOSTLY IN LOW VFR TERRITORY. CIGS SHOULD GRADUALLY SCATTER/LIFT TO VFR BY LATE THIS AFTERNOON OR EARLY THIS EVENING AT ALL OF THE TERMINALS. IN ADDITION...AN ISOLATED SHOWER OR STORM COULD VISIT THE TERMINALS ALMOST ANY TIME OVER THE NEXT 24 HOURS...THOUGH OVERALL PROBABILITIES OF A DIRECT IMPACT ARE TOO LOW TO INCLUDE EXPLICITLY IN THE TAFS. BREEZY NORTHEASTERLY WIND THIS MORNING WILL GRADUALLY WEAKEN THIS AFTERNOON. && .PREV DISCUSSION... /ISSUED 335 AM CDT SAT SEP 19 2015/ SHORT TERM... THE MAIN THEME TODAY WILL BE MUCH COOLER WEATHER THANKS TO A COLD FRONT THAT MOVED THROUGH FRIDAY EVENING. THE COLD FRONT HAS ALREADY EXITED THE SOUTHERN ZONES AND IS FORECAST TO STALL OUT WELL TO OUR SOUTH NEAR I-10 THIS AFTERNOON. BEHIND THE FRONT...WE HAVE SEEN A LITTLE CONVECTION LINGER ACROSS THE ROLLING PLAINS EARLY THIS MORNING...WITH SOME ADDITIONAL CONVECTION TIED TO AN ELEVATED FRONTAL ZONE FROM THE CENTRAL TEXAS PANHANDLE INTO WESTERN OKLAHOMA. ALTHOUGH WE COULD SEE A FEW ELEVATED SHOWERS AND STORMS LINGER INTO THE DAY TODAY...THE MORE CERTAIN BET IS FOR WIDESPREAD LOW CLOUDS TO FILL IN ACROSS THE AREA. THESE STUBBORN CLOUDS ALONG WITH PERSISTENT NORTHEASTERLY BREEZES WILL PROVIDE A MUCH COOLER DAY TODAY. IN FACT HIGHS TODAY WILL BE SOME 25 TO 30 DEGREES COOLER THAN YESTERDAY...ONLY TOPPING OUT IN THE LOWER TO MIDDLE 70S AT MOST SPOTS. REGARDING PRECIPITATION CHANCES...IT IS TOUGH TO FIND ANY GOOD FORCING WITH THE SURFACE FRONT WELL TO THE SOUTH AND SURFACE RIDGING BUILDING IN...BUT WITH A RELATIVELY MOIST TROPOSPHERE IN PLACE IT WILL NOT TAKE MUCH EITHER...SO WE HAVE CONTINUED WITH SLIGHT CHANCE TO LOW CHANCE POPS TODAY /FAVORING THE SOUTHERN ZONES/. THE NWP SUPPORTS THIS TOO...WITH LIGHT QPF SMATTERED ABOUT THE CWA BUT NO CLEAR COHERENT SIGNAL. WE WILL THEN SEE AN UPTICK IN ISENTROPIC UPGLIDE TONIGHT AS A MODEST SOUTHERLY LLJ DEVELOPS. THIS COUPLED WITH A POSSIBLE EMBEDDED DISTURBANCE AND EVEN RICHER DEEP LAYER MOISTURE APPROACHING FROM THE SOUTHWEST COULD IMPROVE OUR RAIN CHANCES SOMEWHAT...THOUGH THE BEST FORCING MAY STAY SOUTH AND WEST OF THE CWA. THE NWP GUIDANCE IS NOT OVERWHELMING WITH REGARDS TO QPF PRODUCTION LOCALLY EITHER...LIMITING OVERALL CONFIDENCE IN RAIN CHANCES. GIVEN THIS WE HAVE CARRIED LOW CHANCE POPS FOR MOST OF THE FA TONIGHT. THE RELATIVELY MOIST AND MOSTLY CLOUDY CONDITIONS WILL HELP SECURE A MILD NIGHT WITH LOWS RANGING FROM THE UPPER 50S ACROSS THE SOUTHWEST TEXAS PANHANDLE TO MIDDLE 60S IN THE ROLLING PLAINS. LONG TERM... THE RETURN OF SOUTHERLY FLOW BRINGING WARMER TEMPS...LINGERING MOISTURE...AND A PASSING WEAK SHORTWAVE ARGUE FOR MAINTAINING A CHANCE OF RAIN ACROSS THE AREA ON SUNDAY. QPF SIGNALS IN THE GUIDANCE ARE PRETTY WEAK AND THERE IS SOME QUESTION REGARDING THE DEGREE OF INSTABILITY WITH SURFACE TEMPS REMAINING RELATIVELY COOL /80S/...SO WE`VE KEPT POPS IN THE 20 TO 30 PERCENT RANGE. THE UPPER WAVE MOVES OFF ON MONDAY WITH RIDGING BUILDING IN OVER NEW MEXICO AND WEST TEXAS. THIS WILL RESULT IN WARMER AND DRIER CONDITIONS WITH HIGHS BACK UP NEAR 90 FOR MONDAY AND TUESDAY. MEANWHILE...WE ARE STILL LOOKING FOR A PLUME OF SUB-TROPICAL MOISTURE TO SPREAD OVER THE DESERT SOUTHWEST DOWNSTREAM OF AN UPPER LOW APPROACHING THE SOUTHERN CALIFORNIA COAST. A SHORTWAVE EMBEDDED IN THIS PLUME SHOULD SPREAD SHOWER AND T-STORM ACTIVITY NEWD ACROSS NEW MEXICO...AND PERHAPS BRUSH OUR COUNTIES ALONG THE TX/NM STATE LINE LATE TUESDAY. THE UPPER LOW WEAKENS AND EJECTS NEWD ACROSS THE SRN ROCKIES AROUND MIDWEEK. THE GFS AND ECMWF CONTINUE TO DIFFER ON THE TRACK OF THE SYSTEM...WITH THE ECMWF SOMEWHAT DEEPER AND SLOWER THAN THE GFS. THE ECMWF SOLUTION MAY SUPPORT SOME RAIN CHANCES FOR PORTIONS OF THE AREA ON THURSDAY. A NARROW UPPER RIDGE WILL AMPLIFY FROM SW TO NE ACROSS THE REGION LATE WEEK IN RESPONSE TO A LARGE TROUGH MOVING ONTO THE WEST COAST. THIS SHOULD KEEP RAIN CHANCES LOW AND TEMPS ABOVE NORMAL THROUGH THE END OF THE WEEK. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 70 58 85 60 / 20 20 20 10 TULIA 70 58 83 60 / 20 20 20 20 PLAINVIEW 70 60 83 61 / 20 30 20 10 LEVELLAND 73 61 83 62 / 20 30 20 10 LUBBOCK 73 62 84 63 / 20 30 20 10 DENVER CITY 74 62 82 62 / 30 40 20 10 BROWNFIELD 74 62 83 63 / 30 30 20 10 CHILDRESS 74 63 85 66 / 20 30 30 20 SPUR 74 63 85 65 / 20 30 20 10 ASPERMONT 78 66 88 66 / 30 30 30 10 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 23/33/23
Area Forecast Discussion National Weather Service Midland/Odessa TX 639 AM CDT SAT SEP 19 2015 .DISCUSSION... && .AVIATION... Cold front moving through the area and storms beginning to develop over the Central Permian Basin. Expect storm coverage to increase... have TSRA in all TAFs. Low clouds moving south behind the front with low MVFR cigs. && .PREV DISCUSSION... /issued 423 AM CDT SAT SEP 19 2015/ DISCUSSION...As of 4:00 AM CDT Saturday...a brief respite from the heat this weekend. Sfc obs and KMAF radar is indc that a cold front is currently over the Central Permian Basin. A few small thunderstorms are popping up behind the front. There are also a few thunderstorms along the Rio Grande in Northwest Presidio County along the edge of a large MCS centered over portions of Sonora and Chihuahua Mexico. The HRRR and RAP13 hi-res models move the cold front slowly south this morning...stalling near or north of I-10 this aftn. With good low-level convergence and weak mid level impulses the hi-res models bring a good shot of convection along the I-20 corridor this morning...moving south this aftn. The main impacts from the thunderstorms will be locally heavy rain and gusty winds. With the rain potential and cloud cover it will be significantly cooler than yesterday...in fact today should be the coolest day this month. Have continued convective chances tonight with the front over the CWA. The cold front will retreat north/wash out on Sunday as a ridge builds back into the Southern Plains/Rockies. Temps will warm to near seasonal levels on Sunday with a slight chance of thunderstorms. A blocking pattern develops over the CONUS next week with a trough along both coasts and a ridge over the Central US. Shortwaves will ride over the ridge...occasionally flattening it slightly. The Davis Mtns...and even more so the Guadalupe Mtns will be on the eastern edge of any convective activity into mid week. Otherwise...the rest of the CWA will be dry. Even though the center of the H85 thermal ridge will be just west of the CWA expect temps next week to be 5-10 degrees above normal...with widespread low 90s and even a few mid 90s across the lower elevations. Widespread 80s are expected in the Mtns...with upper 80s along the extreme northern portions of the CWA. The latest GFS ensemble forecasts keeps West Texas/Southeast New Mexico dry with above normal temperatures through the end of September and into the first several days of October. Strobin && .MAF WATCHES/WARNINGS/ADVISORIES... NM...NONE. TX...NONE. && $$
AREA FORECAST DISCUSSION
NWS AMARILLO TX
459 AM CDT SAT SEP 19 2015 .DISCUSSION... EARLY THIS MORNING THE SURFACE COLD FRONT HAD PROGRESSED WELL TO THE SOUTH OF THE PANHANDLES WITH NORTHEASTERLY SURFACE WINDS IN ITS WAKE. COOLER TEMPERATURES HAVE ARRIVED WITH UPPER 40S AT BOISE CITY AND KENTON. POST-FRONTAL STRATUS SHOULD BE QUITE EXTENSIVE TODAY AS IS EVIDENT BY WEAK ISENTROPIC ASCENT. THIS WILL LIMIT TEMPERATURES AND HAVE WENT ON THE COOL SIDE OF GUIDANCE WHICH MAY NOT BE COOL ENOUGH. THIS IS A DOWNWARD TREND FROM PREVIOUS FORECAST. HAVE STRUGGLED TO FIND A NOTABLE SOURCE FOR LIFT SUFFICIENT FOR PRECIPITATION. MODEL FORECAST SOUNDINGS SHOW A RELATIVELY SHALLOW SATURATION WITHIN THE FRONTAL INVERSION. IF SATURATION IS DEEP ENOUGH FOR ELEVATED CONVECTION IT WOULD BE IN THE SOUTHEAST TEXAS PANHANDLE NEAR WHERE ISOLATED SHOWERS AND THUNDERSTORMS HAVE PERSISTED MUCH OF THE NIGHT BUT CONFIDENCE IS LOW. LOW LEVEL FLOW WILL GRADUALLY BECOME MORE SOUTHEASTERLY BY TOMORROW EVENING AND SLIGHTLY DEEPER MOISTURE ADVECTS NORTHWARD INTO THE AREA. IN THIS SCENARIO SOME CONVECTIVE DEVELOPMENT MAY OCCUR DURING THE EVENING PARTICULARLY ACROSS THE NORTHEASTERN PORTION OF THE AREA AS LOW LEVEL JET STRENGTHENS AND THIS MAY PERSIST INTO SUNDAY MORNING. ANOTHER SHORTWAVE IS DEPICTED TO MOVE THROUGH LATE SUNDAY AND BY THAT TIME CLEARING AND INCREASED DIABATIC HEATING WILL BE SUFFICIENT FOR AT LEAST MODEST INSTABILITY AND SOME DIURNAL CONVECTION LATE SUNDAY LASTING INTO EARLY SUNDAY EVENING. SUBSIDENCE BEHIND THIS WAVE SHOULD BRING AN END TO ANY CONVECTION THAT DOES FORM BY MID EVENING. EARLY NEXT WEEK THE MODELS BUILD AN UPPER RIDGE ACROSS THE SOUTHERN PLAINS RESULTING IN WARMER TEMPERATURES AND DRIER CONDITIONS. A PLUME OF DEEP MOISTURE IS SHOWN TO MOVE NORTHWARD INTO THE DESERT SOUTHWEST ON THE WESTERN SIDE OF THIS RIDGE AND AHEAD OF A CLOSED UPPER LOW APPROACHING THE COAST OF BAJA CALIFORNIA. BY LATE TUESDAY A WEAK SHORTWAVE AHEAD OF THE OPENING CLOSED LOW IN COMBINATION WITH INCREASING MOISTURE MAY LEAD TO SOME CONVECTION IN THE FAR NORTHWEST. BETTER CHANCES WILL ARRIVE WEDNESDAY AS THE MAIN SHORTWAVE APPROACHES. TIMING AND AMPLITUDE DIFFER IN THE MEDIUM RANGE MODELS DIFFER AT THIS TIME RANGE LEADING TO SOME UNCERTAINTY. BRB && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 55 84 61 90 65 / 20 20 20 0 0 BEAVER OK 58 83 60 92 66 / 30 20 10 0 0 BOISE CITY OK 53 85 57 92 63 / 10 5 0 0 0 BORGER TX 59 86 64 92 68 / 20 20 10 0 0 BOYS RANCH TX 58 87 60 91 65 / 20 20 5 0 0 CANYON TX 56 84 60 90 63 / 20 20 20 0 0 CLARENDON TX 60 83 62 91 65 / 30 20 20 0 0 DALHART TX 56 88 58 92 62 / 10 10 5 0 0 GUYMON OK 56 86 60 93 65 / 20 10 5 0 0 HEREFORD TX 56 85 60 90 63 / 20 20 10 0 0 LIPSCOMB TX 60 81 62 90 67 / 30 30 20 0 0 PAMPA TX 59 84 62 91 65 / 30 20 20 0 0 SHAMROCK TX 61 80 62 89 65 / 30 30 20 0 0 WELLINGTON TX 63 81 63 90 66 / 30 30 20 0 0 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 15/17
Area Forecast Discussion National Weather Service Midland/Odessa TX 423 AM CDT SAT SEP 19 2015 .DISCUSSION...As of 4:00 AM CDT Saturday...a brief respite from the heat this weekend. Sfc obs and KMAF radar is indc that a cold front is currently over the Central Permian Basin. A few small thunderstorms are popping up behind the front. There are also a few thunderstorms along the Rio Grande in Northwest Presidio County along the edge of a large MCS centered over portions of Sonora and Chihuahua Mexico. The HRRR and RAP13 hi-res models move the cold front slowly south this morning...stalling near or north of I-10 this aftn. With good low-level convergence and weak mid level impulses the hi-res models bring a good shot of convection along the I-20 corridor this morning...moving south this aftn. The main impacts from the thunderstorms will be locally heavy rain and gusty winds. With the rain potential and cloud cover it will be significantly cooler than yesterday...in fact today should be the coolest day this month. Have continued convective chances tonight with the front over the CWA. The cold front will retreat north/wash out on Sunday as a ridge builds back into the Southern Plains/Rockies. Temps will warm to near seasonal levels on Sunday with a slight chance of thunderstorms. A blocking pattern develops over the CONUS next week with a trough along both coasts and a ridge over the Central US. Shortwaves will ride over the ridge...occasionally flattening it slightly. The Davis Mtns...and even more so the Guadalupe Mtns will be on the eastern edge of any convective activity into mid week. Otherwise...the rest of the CWA will be dry. Even though the center of the H85 thermal ridge will be just west of the CWA expect temps next week to be 5-10 degrees above normal...with widespread low 90s and even a few mid 90s across the lower elevations. Widespread 80s are expected in the Mtns...with upper 80s along the extreme northern portions of the CWA. The latest GFS ensemble forecasts keeps West Texas/Southeast New Mexico dry with above normal temperatures through the end of September and into the first several days of October. Strobin && .PRELIMINARY POINT TEMPS/POPS... BIG SPRING TX 81 64 88 64 / 50 30 20 10 CARLSBAD NM 76 66 87 65 / 40 50 30 10 DRYDEN TX 96 73 94 70 / 20 20 10 10 FORT STOCKTON TX 88 68 89 66 / 40 40 20 10 GUADALUPE PASS TX 71 60 80 62 / 40 50 30 10 HOBBS NM 78 63 84 64 / 30 50 20 10 MARFA TX 81 58 80 57 / 30 30 20 20 MIDLAND INTL AIRPORT TX 84 67 88 66 / 50 40 20 10 ODESSA TX 82 67 87 68 / 50 40 20 10 WINK TX 85 68 88 67 / 50 50 20 10 && .MAF WATCHES/WARNINGS/ADVISORIES... NM...NONE. TX...NONE. && $$ 72/33
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
240 AM CDT SAT SEP 19 2015 .DISCUSSION... THE COLD FRONT WAS LOCATED ALONG A LINE FROM FORT SMITH TO SOUTH OF LUBBOCK AT 07Z/2AM AND MOVING SOUTHEAST NEAR 18 MPH. AN OUTFLOW BOUNDARY AHEAD OF CONVECTION ALONG/BEHIND THE FRONT WILL WORK THROUGH THE NORTHWEST HALF OF THE CWA THIS MORNING WITH CONVECTION SPREADING SOUTHEASTWARD AS WELL. THE HRRR AND TT WRF SPREAD CONVECTION INTO THE NORTHWEST HALF OF THE DFW METROPLEX 10-12Z SO HAVE MAINTAINED CHANCE POPS OVER THE NORTHWEST HALF TODAY. THE FRONT WILL LIKELY MOVE TO NEAR A PALESTINE TO GOLDTHWAITE LINE BY MIDNIGHT TONIGHT...THEN DRIFT NORTHWARD A LITTLE EARLY SUNDAY AND STALL OUT JUST SOUTH OF I-20 DURING THE DAY WITH THE BEST CHANCE OF CONVECTION GENERALLY NORTH OF THE FRONT. THE WEST END OF THE FRONT LIFTS NORTHWARD ON SUNDAY NIGHT AND THEN THE ENTIRE FRONT LIFTS OUT NORTHEAST ON MONDAY. SUNDAY NIGHT POPS WILL SHIFT TO THE NORTHEAST COUNTIES AND MONDAY POPS WILL BE MAINLY OVER THE FAR EASTERN COUNTIES. SOME STRONG THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING DUE TO A FAIR AMOUNT OF INSTABILITY ALONG THE FRONT....AND LOCALIZED HEAVY RAINFALL IS ALSO POSSIBLE DUE TO PWATS NEAR/AROUND 2 INCHES. HIGH TEMPERATURES TODAY WILL NOT CHANGE AHEAD OF THE FRONT BUT THEY WILL BE 5-10 DEGREES COOLER BEHIND IT. AS THE FRONT BECOMES DIFFUSED ON SUNDAY AND LIFTS OUT ON MONDAY...HIGH TEMPS WILL CREEP UPWARD WITH MOST OF THE CWA BACK IN THE LOWER TO MID 90S TUESDAY THROUGH FRIDAY. HAVE ADJUSTED OVERNIGHT LOWS DOWN 1-3 DEGREES...MAINLY RURAL AREAS...THURSDAY AND FRIDAY DUE TO DRIER AIR SPREADING INTO THE REGION. LOOKING AHEAD INTO NEXT WEEKEND AND THE LAST WEEK OF SEPTEMBER...BOTH THE GFS AND ECMWF MODELS ARE INDICATING A WEAKNESS ALOFT OVER THE SOUTHEAST OR SOUTHERN STATES AND THE UPPER RIDGE OFF TO OUR WEST. THIS PATTERN WOULD RESULT IN LOWER HEIGHTS ALOFT OVER NORTH AND CENTRAL TEXAS...AND THUS TEMPERATURES A LITTLE CLOSER TO NORMAL WITH HIGHS IN THE MID 80S TO LOWER 90S. 75 && .AVIATION... /ISSUED 1153 PM CDT FRI SEP 18 2015/ NOT MUCH CHANGE FROM THE 00Z FORECAST WITH GENERALLY VFR CONDITIONS THROUGH SATURDAY AND INCREASING CLOUD COVER ASSOCIATED WITH AN APPROACHING COLD FRONT. THE COLD FRONT CONTINUES TO MAKE STEADY PROGRESS SOUTHWARD LATE THIS EVENING AND SHOULD APPROACH THE METROPLEX TAF SITES JUST AFTER DAYBREAK WHICH IS A FEW HOURS EARLIER THAN PREVIOUSLY THOUGHT. THE ARRIVAL OF THE FRONT WILL BRING SCATTERED SHOWERS AND THUNDERSTORMS. HOWEVER...MOISTURE AND UPPER LEVEL SUPPORT WILL BE SOMEWHAT LIMITED SO WILL ONLY MENTION VCTS AT THE METROPLEX TERMINALS. THE FRONT SHOULD STALL NORTH OF WACO AND STORM CHANCES WILL BE EVEN LOWER THERE. EXPECT SOUTHERLY WINDS BETWEEN 8 AND 12 KNOTS AHEAD OF THE COLD FRONT. THE WIND WILL TURN TO THE NORTH/NORTHEAST AT THE METROPLEX TERMINALS BETWEEN 13 AND 15Z AND REMAIN FROM THE NORTHEAST THROUGH SATURDAY EVENING. 79 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 88 72 90 72 92 / 40 30 20 10 5 WACO, TX 93 70 95 71 93 / 20 10 10 5 5 PARIS, TX 87 67 87 66 87 / 30 20 30 30 20 DENTON, TX 87 69 89 68 91 / 40 40 20 20 5 MCKINNEY, TX 88 69 90 69 90 / 40 30 20 20 10 DALLAS, TX 89 73 90 71 92 / 40 30 20 10 5 TERRELL, TX 91 69 91 69 91 / 20 20 20 20 10 CORSICANA, TX 94 71 93 71 92 / 10 10 10 5 10 TEMPLE, TX 93 69 93 70 92 / 10 10 5 5 5 MINERAL WELLS, TX 87 67 90 68 91 / 40 40 20 10 5 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ /75
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
934 PM EDT SUN SEP 20 2015 .SYNOPSIS... A COLD FRONT WILL CONTINUE TO PUSH SOUTHEAST OF THE REGION TONIGHT ALLOWING COOL HIGH PRESSURE TO BUILD SOUTH ALONG THE EAST SIDE OF THE APPALACHIANS BEHIND THE FRONT OVERNIGHT. THIS CHANGE IN AIRMASS WILL RESULT IN LOWER TEMPERATURES OVER THE NEXT COUPLE OF DAYS. INCREASING MOISTURE ASSOCIATED WITH ONSHORE EASTERLY FLOW WILL COMBINE WITH A WEAK UPPER LEVEL DISTURBANCE TO RESULT IN ABUNDANT CLOUD COVER ACROSS THE REGION ALONG WITH THE POTENTIAL FOR AREAS OF RAIN MONDAY INTO TUESDAY. && .NEAR TERM /THROUGH MONDAY/... AS OF 930 PM EDT SUNDAY... THE LATE EVENING FORECAST UPDATE WILL REFLECT ONE PRIMARY ADJUSTMENT TO THE ONGOING FORECAST. THE LATEST MESOSCALE MODELS OFFER A SOLUTION THAT REDUCES THE EXTENT THAT PRECIPITATION DEVELOPMENT WILL TAKE PLACE OVER THE EASTERN AND NORTHWESTERN PARTS OF THE AREA UNTIL AFTER ROUGHLY 200 AM MONDAY. HOWEVER...THESE LATEST SOLUTIONS ALSO CONTINUE TO CONFIRM A HIGH PROBABILITY OF PRECIPITATION ALONG AND NEAR THE CREST OF THE BLUE RIDGE THROUGH...AND AFTER...THE SAME TIME PERIOD SOUTHWEST OF ROANOKE VIRGINIA. THE LATEST FORECAST UPDATE WILL REFLECT THESE TRENDS. NO OTHER SIGNIFICANT CHANGES ARE EXPECTED. MINOR ADJUSTMENTS TO HOURLY TEMPERATURE AND DEW POINT WILL REFLECT THE LATEST OBSERVATIONS AND EXPECTED TRENDS THROUGH ROUGHLY 200 AM. AS OF 625 PM EDT SUNDAY... EARLY EVENING UPDATE WILL REFLECT A GREATER CONCENTRATION OF SHOWERS THAN ISOLATED WITHIN AN AREA AROUND MARTINSVILLE VIRGINIA...WEST TO NEAR THE CREST OF THE BLUE RIDGE. ALSO...A CLUSTER OF SHOWERS WAS SOUTH OF THIS REGION ACROSS CENTRAL STOKES COUNTY NORTH CAROLINA. THIS COLLECTION OF SHOWERS MATCHES WELL WITH A NOSE OF MORE UNSTABLE AIR WITH SURFACE BASED CONVECTIVE AVAILABLE POTENTIAL ENERGY OF 500-1000 JOULES PER KILOGRAM AND SURFACE BASED LIFTED INDICES OF -1 TO -2 C. THIS AREA...AND IMMEDIATELY DOWNSTREAM TOWARDS ROCKINGHAM COUNTY NORTH CAROLINA AND PITTSYLVANIA COUNTY VIRGINIA ARE EXPECTED TO EXPERIENCE SOMEWHAT HIGHER THAN EARLIER PROJECTED PROBABILITY OF PRECIPITATION OVER THE NEXT FEW HOURS. NO OTHER SIGNIFICANT CHANGES WERE MADE TO THE FORECAST AT THIS TIME. TWEAKS OF HOURLY TEMPERATURE...DEW POINT...WIND AND SKY COVER WERE MADE THROUGH THE LATE EVENING HOURS BASED UPON THE LATEST OBSERVATIONS AND EXPECTED TRENDS OVER THE NEXT FEW HOURS. AS OF 300 PM EDT SUNDAY... A COLD FRONT TO OUR SOUTH THIS AFTERNOON WILL CONTINUE TO PUSH SOUTHEAST IN THE ATLANTIC TONIGHT INTO MONDAY. ISOLATED TO SCATTERED CONVECTION HAS FORM IN THE UNSTABLE AIR THIS AFTERNOON MAINLY ALONG THE SOUTHERN BLUE RIDGE. SPC 18Z MESOSCALE ANAL INDICATED SBCAPE AROUND 500 J/KG ALONG THE EASTERN SLOPES OF THE BLUE RIDGE INTO NORTH CAROLINA. KFCX RADAR IMAGES INDICATED SHOWERS FORMING WITH DEEP LAYER MOIST FLUX CONVERGENCE. TRIMMED BACK THUNDERSTORMS FOR THIS AFTERNOON INTO TONIGHT...BUT ALLOWED FOR SOME ISOLATED STORMS AS HIGHLIGHTED IN THE SPC DAY ONE CONVECTIVE OUTLOOK. INITIALLY...SHAPED POPS TOWARDS A BLEND OF HRRR AND RNK WRFARW THIS AFTERNOON INTO THIS EVENING FOR CONVECTION...THEN INCREASE CHANCES WITH RAIN TONIGHT. AS HIGH PRESSURE TO OUR NORTH BUILDS SOUTHEAST TONIGHT ALONG THE EAST SIDE OF THE APPALACHIANS...A LOW LEVEL EASTERLY WIND WILL DEVELOP PROMOTING UPSLOPE CLOUDS AND THE DEVELOPMENT OF AREAS OF LIGHT RAIN AND DRIZZLE. HIGHEST POPS WILL BE ALONG THE BLUE RIDGE WHERE THE UPSLOPE LOW LEVEL UVM COMPONENT WILL BE THE GREATEST. IN SPITE OF THE PRECIPITATION...AMOUNTS ARE EXPECTED TO BE LIGHT...LESS THAN A QUARTER OF AN INCH. LOW TEMPERATURES TONIGHT WILL VARY FROM AROUND 50 DEGREES IN THE MOUNTAINS TO THE LOWER 60S IN THE PIEDMONT. ON MONDAY...AN UPPER LEVEL TROUGH WILL DEEPEN AS IT DRIFTS EASTWARD FROM NEAR THE MISSISSIPPI VALLEY TOWARD THE APPALACHIANS. MEANWHILE HIGH PRESSURE EXTENDING SOUTHWARD FROM NEW ENGLAND...WILL PUSH MOISTURE INTO THE EASTERN FACE OF THE APPALACHIANS. WIDESPREAD RAIN IS EXPECTED MONDAY...ESPECIALLY ALONG THE BLUE RIDGE. UPSLOPE FLOW COMBINED WITH RICH CLOUD COVER WILL RESULT IN COOL CONDITIONS MONDAY WITH HIGH TEMPERATURES VARYING FROM THE MID 50S IN THE MOUNTAINS TO THE MID 60S IN THE PIEDMONT. SOME WARMER TEMPERATURES MAY SLIDE INTO THE FAR WEST ALLOWING READINGS TO CLIMB TO AROUND 70 DEPENDING ON THE STRENGTH OF THE COOL WEDGE. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... AS OF 230 PM EDT SUNDAY... STRONG WEDGE WILL REMAIN IN PLACE MONDAY NIGHT WITH FORECAST SOUNDINGS SHOWING ENOUGH DEEP MOISTURE PER CONTINUED UPSLOPE EARLY...AND SHORTWAVE ENERGY ROTATING THROUGH UNDER THE OHIO VALLEY UPPER TROUGH TO KEEP PERIODS OF RAIN/DRIZZLE GOING OVERNIGHT. MOISTURE DEPTH MAY DECREASE SOME LATE MONDAY NIGHT AS THE FLOW TURNS MORE NORTHERLY SO GOING WITH HIGHEST CHANCE/LOW LIKELY POPS DURING THE EVENING OTHERWISE CONTINUED DAMP AND COOL OVERNIGHT. COLUMN SHOULD CONTINUE TO DRY TUESDAY INTO TUESDAY NIGHT AS THE COMBINATION OF LOW PRESSURE OFFSHORE AND HIGH PRESSURE BUILDING IN FROM THE NORTH ENHANCES A DRIER NORTH TO NE TRAJECTORY. HOWEVER WITH THE UPPER COLD POOL CLOSING OFF ACROSS THE WEST...MAY SEE ADDED SHRA BANDS IN THE AFTERNOON WITH ANY INSOLATION AS GUIDANCE SHOWING A SMALL RIBBON OF INSTABILITY FAR WEST. OTHERWISE WILL INIT WITH MORE STRATIFORM LIGHT RAIN EARLY TUESDAY...GIVING WAY TO MORE CONVECTIVE NATURE IN THE AFTERNOON WITH MAINLY CHANCE POPS MOUNTAINS WHERE SUPPORTED BY SOME NORTH/NE FLOW CONVERGENCE INTO EARLY TUESDAY EVENING BEFORE DRYING OUT OVERNIGHT. GIVEN A LITTLE MORE SUNSHINE EXPECT HIGH TEMPS TO REBOUND A LITTLE PENDING HOW FAST THE WEDGE ERODES. THUS STAYED BELOW MOS FOR HIGHS WITH MAINLY 65-70 NEAR THE BLUE RIDGE AND LOW 70S PIEDMONT AND FAR WEST. UPPER LOW SHIFTS TO THE SOUTH WEDNESDAY ALLOWING INCREASING SUBSIDENCE AND ADDED DRYING AS STRONG HIGH PRESSURE BUILDS IN FROM THE NORTH. THIS ALONG WITH A DRY NORTHERLY FLOW SHOULD RESULT IN A SUNNY AND MILDER DAY WEDNESDAY WITH HEATING OF DRY AIR PUSHING HIGHS BACK INTO THE MID/UPPER 70S OVERALL. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 1230 PM EDT SUNDAY... ENSEMBLES CONTINUE TO SHOW A MOSTLY DRY PERIOD INTO NEXT WEEKEND AS THE RESIDUAL UPPER LOW ACROSS THE CAROLINAS DURING MIDWEEK DROPS FARTHER SOUTH BEFORE RETROGRADING NW INTO THE TN VALLEY BY THE END OF THE PERIOD. THIS SHOULD ALLOW SOME DEGREE OF UPPER RIDGING TO TAKE SHAPE OVER THE MID ATLANTIC THROUGH THE END OF THE WEEK BEFORE HEIGHTS LOWER A BIT WITH THE UPPER SYSTEM SLIDING NORTHWARD. PASSING MID LEVEL TROFFINESS WELL TO THE NE WILL ALSO ALLOW A LARGE AREA OF SURFACE HIGH PRESSURE TO SPILL SOUTH LEADING TO ADDITIONAL LOW LEVEL WEDGING BY THE WEEKEND. HOWEVER STILL SOME UNCERTAINTY GIVEN THE PERSISTENT WET TREND OFF THE OPERATIONAL GFS SOLUTIONS AND A FEW OF ITS ENSEMBLE MEMBERS IN KEEPING THE CLOSED LOW SPINNING OVER THE CAROLINAS. THIS SCENARIO EVENTUALLY TAPS INTO MOISTURE WITH LOW PRESSURE OFFSHORE AND MAKES FOR QUITE AN ONSHORE TAP OF SHOWERS THROUGH MUCH OF THE PERIOD. SINCE THIS REMAINS AN OVERALL OUTLIER AT THIS POINT...WILL STAY CONSISTENT AND REMAIN CLOSER TO THE EARLIER 00Z CMC/12Z EC...AND GO MAINLY DRY EXCEPT FOR ISOLATED OROGRAPHIC AIDED SHOWERS SW FRIDAY...AND OVER SOUTHERN/CENTRAL SECTIONS SATURDAY INTO SUNDAY AS SOME LOW LEVEL MOISTURE RETURNS. OTHERWISE DRY WEDGE APPEARS TOO STRONG EVEN FOR LOW CLOUDS SO RUNNING PC/MOSTLY SUNNY WITH MORE CLOUDS BY THE WEEKEND. TEMPS REMAIN MILD BUT OVERALL STILL CLOSE TO SEASONAL NORMALS...MOSTLY 70S FOR HIGHS BUT COOL 50S AT NIGHT. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... AS OF 740 PM EDT SUNDAY... DETERIORIATING AVIATION CONDITIONS THIS TAF VALID PERIOD. A WEDGE OF MOIST...COOL AIR IS IN THE PROCESS OF DEVELOPING ACROSS THE CWA AS A LARGE AREA OF HIGH PRESSURE SLIDES FROM THE EASTERN GREAT LAKES TOWARD NEW ENGLAND. CLOUDS HAVE BEEN ON THE INCREASE ALL AFTERNOON AND CIGS ARE BEGINNING TO LOWER INTO THE MVFR RANGE ALONG THE EAST FACING SLOPES OF THE BLUE RIDGE. EXPECT CLOUD COVER TO CONTINUE TO INCREASE OVERNIGHT TO ENCOMPASS THE ENTIRE CWA WITH CIGS LOWERING MOSTLY INTO THE LOW END OF THE MVFR CATEGORY...BUT IFR AT THE HIGHER ELEVATIONS...KBCB/KBLF...AND EVENTUALLY MOST SITES BY 12Z MON. WEDGE WILL PERSIST MON...THUS LITTLE TO NO IMPROVEMENT IS EXPECTED THROUGH THE DAY. VISIBILITIES WILL TEND TO BE A LITTLE MORE DIFFICULT TO PREDICT. RADIATIONAL FOG WILL NOT BE AN ISSUE TONIGHT...NOT EVEN AT LWB. HOWEVER...IN SOME LOCATIONS WHERE CIGS DROP TO LOW END IFR OR INTO THE LIFR CATEGORY...VSBYS WILL ALSO BECOME IFR OR WORSE. MOSTLY EXPECTING MVFR CIGS IN -RA...-DZ...AND BR. WINDS...IF NOT ALREADY...BECOMING NE-ENE 5-7KTS THROUGH THE TAF VALID PERIOD...EXCEPT ESE 6-8KTS KBLF. MEDIUM CONFIDENCE IN CIGS THROUGHOUT THE TAF VALID PERIOD. MEDIUM CONFIDENCE IN VSBYS THROUGHOUT THE TAF VALID PERIOD. MEDIUM TO HIGH CONFIDENCE IN WIND SPEED/DIRECTION THROUGH THE TAF VALID PERIOD. EXTENDED AVIATION DISCUSSION... THE WEDGE WILL GRADUALLY DISSIPATE BY MIDWEEK ALLOWING CONDITIONS TO RETURN TO VFR FOR MID/LATE WEEK. SOME FORECAST MODELS INDICATE THAT LOW PRESSURE MAY RETROGRADE WESTWARD FROM THE EAST COAST LATE IN THE WEEK BRINGING CLOUDS AND PRECIPITATION...BUT CONFIDENCE IS LOW AT THIS TIME AS SEVERAL MODELS DO NOT SHOW THIS POSSIBILITY...RATHER KEEPING THE SYSTEM FURTHER EAST AND OFF THE COAST AND WITH HIGH PRESSURE OVER OUR REGION. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...JH/PM NEAR TERM...DS/KK SHORT TERM...JH LONG TERM...JH AVIATION...KK/RAB
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
746 PM EDT SUN SEP 20 2015 .SYNOPSIS... A COLD FRONT WILL CONTINUE TO PUSH SOUTHEAST OF THE REGION TONIGHT ALLOWING COOL HIGH PRESSURE TO BUILD SOUTH ALONG THE EAST SIDE OF THE APPALACHIANS BEHIND THE FRONT OVERNIGHT. THIS CHANGE IN AIRMASS WILL RESULT IN LOWER TEMPERATURES OVER THE NEXT COUPLE OF DAYS. INCREASING MOISTURE ASSOCIATED WITH ONSHORE EASTERLY FLOW WILL COMBINE WITH A WEAK UPPER LEVEL DISTURBANCE TO RESULT IN ABUNDANT CLOUD COVER ACROSS THE REGION ALONG WITH THE POTENTIAL FOR AREAS OF RAIN MONDAY INTO TUESDAY. && .NEAR TERM /THROUGH MONDAY/... AS OF 625 PM EDT SUNDAY... EARLY EVENING UPDATE WILL REFLECT A GREATER CONCENTRATION OF SHOWERS THAN ISOLATED WITHIN AN AREA AROUND MARTINSVILLE VIRGINIA...WEST TO NEAR THE CREST OF THE BLUE RIDGE. ALSO...A CLUSTER OF SHOWERS WAS SOUTH OF THIS REGION ACROSS CENTRAL STOKES COUNTY NORTH CAROLINA. THIS COLLECTION OF SHOWERS MATCHES WELL WITH A NOSE OF MORE UNSTABLE AIR WITH SURFACE BASED CONVECTIVE AVAILABLE POTENTIAL ENERGY OF 500-1000 JOULES PER KILOGRAM AND SURFACE BASED LIFTED INDICES OF -1 TO -2 C. THIS AREA...AND IMMEDIATELY DOWNSTREAM TOWARDS ROCKINGHAM COUNTY NORTH CAROLINA AND PITTSYLVANIA COUNTY VIRGINIA ARE EXPECTED TO EXPERIENCE SOMEWHAT HIGHER THAN EARLIER PROJECTED PROBABILITY OF PRECIPITATION OVER THE NEXT FEW HOURS. NO OTHER SIGNIFICANT CHANGES WERE MADE TO THE FORECAST AT THIS TIME. TWEAKS OF HOURLY TEMPERATURE...DEW POINT...WIND AND SKY COVER WERE MADE THROUGH THE LATE EVENING HOURS BASED UPON THE LATEST OBSERVATIONS AND EXPECTED TRENDS OVER THE NEXT FEW HOURS. AS OF 300 PM EDT SUNDAY... A COLD FRONT TO OUR SOUTH THIS AFTERNOON WILL CONTINUE TO PUSH SOUTHEAST IN THE ATLANTIC TONIGHT INTO MONDAY. ISOLATED TO SCATTERED CONVECTION HAS FORM IN THE UNSTABLE AIR THIS AFTERNOON MAINLY ALONG THE SOUTHERN BLUE RIDGE. SPC 18Z MESOSCALE ANAL INDICATED SBCAPE AROUND 500 J/KG ALONG THE EASTERN SLOPES OF THE BLUE RIDGE INTO NORTH CAROLINA. KFCX RADAR IMAGES INDICATED SHOWERS FORMING WITH DEEP LAYER MOIST FLUX CONVERGENCE. TRIMMED BACK THUNDERSTORMS FOR THIS AFTERNOON INTO TONIGHT...BUT ALLOWED FOR SOME ISOLATED STORMS AS HIGHLIGHTED IN THE SPC DAY ONE CONVECTIVE OUTLOOK. INITIALLY...SHAPED POPS TOWARDS A BLEND OF HRRR AND RNK WRFARW THIS AFTERNOON INTO THIS EVENING FOR CONVECTION...THEN INCREASE CHANCES WITH RAIN TONIGHT. AS HIGH PRESSURE TO OUR NORTH BUILDS SOUTHEAST TONIGHT ALONG THE EAST SIDE OF THE APPALACHIANS...A LOW LEVEL EASTERLY WIND WILL DEVELOP PROMOTING UPSLOPE CLOUDS AND THE DEVELOPMENT OF AREAS OF LIGHT RAIN AND DRIZZLE. HIGHEST POPS WILL BE ALONG THE BLUE RIDGE WHERE THE UPSLOPE LOW LEVEL UVM COMPONENT WILL BE THE GREATEST. IN SPITE OF THE PRECIPITATION...AMOUNTS ARE EXPECTED TO BE LIGHT...LESS THAN A QUARTER OF AN INCH. LOW TEMPERATURES TONIGHT WILL VARY FROM AROUND 50 DEGREES IN THE MOUNTAINS TO THE LOWER 60S IN THE PIEDMONT. ON MONDAY...AN UPPER LEVEL TROUGH WILL DEEPEN AS IT DRIFTS EASTWARD FROM NEAR THE MISSISSIPPI VALLEY TOWARD THE APPALACHIANS. MEANWHILE HIGH PRESSURE EXTENDING SOUTHWARD FROM NEW ENGLAND...WILL PUSH MOISTURE INTO THE EASTERN FACE OF THE APPALACHIANS. WIDESPREAD RAIN IS EXPECTED MONDAY...ESPECIALLY ALONG THE BLUE RIDGE. UPSLOPE FLOW COMBINED WITH RICH CLOUD COVER WILL RESULT IN COOL CONDITIONS MONDAY WITH HIGH TEMPERATURES VARYING FROM THE MID 50S IN THE MOUNTAINS TO THE MID 60S IN THE PIEDMONT. SOME WARMER TEMPERATURES MAY SLIDE INTO THE FAR WEST ALLOWING READINGS TO CLIMB TO AROUND 70 DEPENDING ON THE STRENGTH OF THE COOL WEDGE. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... AS OF 230 PM EDT SUNDAY... STRONG WEDGE WILL REMAIN IN PLACE MONDAY NIGHT WITH FORECAST SOUNDINGS SHOWING ENOUGH DEEP MOISTURE PER CONTINUED UPSLOPE EARLY...AND SHORTWAVE ENERGY ROTATING THROUGH UNDER THE OHIO VALLEY UPPER TROUGH TO KEEP PERIODS OF RAIN/DRIZZLE GOING OVERNIGHT. MOISTURE DEPTH MAY DECREASE SOME LATE MONDAY NIGHT AS THE FLOW TURNS MORE NORTHERLY SO GOING WITH HIGHEST CHANCE/LOW LIKELY POPS DURING THE EVENING OTHERWISE CONTINUED DAMP AND COOL OVERNIGHT. COLUMN SHOULD CONTINUE TO DRY TUESDAY INTO TUESDAY NIGHT AS THE COMBINATION OF LOW PRESSURE OFFSHORE AND HIGH PRESSURE BUILDING IN FROM THE NORTH ENHANCES A DRIER NORTH TO NE TRAJECTORY. HOWEVER WITH THE UPPER COLD POOL CLOSING OFF ACROSS THE WEST...MAY SEE ADDED SHRA BANDS IN THE AFTERNOON WITH ANY INSOLATION AS GUIDANCE SHOWING A SMALL RIBBON OF INSTABILITY FAR WEST. OTHERWISE WILL INIT WITH MORE STRATIFORM LIGHT RAIN EARLY TUESDAY...GIVING WAY TO MORE CONVECTIVE NATURE IN THE AFTERNOON WITH MAINLY CHANCE POPS MOUNTAINS WHERE SUPPORTED BY SOME NORTH/NE FLOW CONVERGENCE INTO EARLY TUESDAY EVENING BEFORE DRYING OUT OVERNIGHT. GIVEN A LITTLE MORE SUNSHINE EXPECT HIGH TEMPS TO REBOUND A LITTLE PENDING HOW FAST THE WEDGE ERODES. THUS STAYED BELOW MOS FOR HIGHS WITH MAINLY 65-70 NEAR THE BLUE RIDGE AND LOW 70S PIEDMONT AND FAR WEST. UPPER LOW SHIFTS TO THE SOUTH WEDNESDAY ALLOWING INCREASING SUBSIDENCE AND ADDED DRYING AS STRONG HIGH PRESSURE BUILDS IN FROM THE NORTH. THIS ALONG WITH A DRY NORTHERLY FLOW SHOULD RESULT IN A SUNNY AND MILDER DAY WEDNESDAY WITH HEATING OF DRY AIR PUSHING HIGHS BACK INTO THE MID/UPPER 70S OVERALL. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 1230 PM EDT SUNDAY... ENSEMBLES CONTINUE TO SHOW A MOSTLY DRY PERIOD INTO NEXT WEEKEND AS THE RESIDUAL UPPER LOW ACROSS THE CAROLINAS DURING MIDWEEK DROPS FARTHER SOUTH BEFORE RETROGRADING NW INTO THE TN VALLEY BY THE END OF THE PERIOD. THIS SHOULD ALLOW SOME DEGREE OF UPPER RIDGING TO TAKE SHAPE OVER THE MID ATLANTIC THROUGH THE END OF THE WEEK BEFORE HEIGHTS LOWER A BIT WITH THE UPPER SYSTEM SLIDING NORTHWARD. PASSING MID LEVEL TROFFINESS WELL TO THE NE WILL ALSO ALLOW A LARGE AREA OF SURFACE HIGH PRESSURE TO SPILL SOUTH LEADING TO ADDITIONAL LOW LEVEL WEDGING BY THE WEEKEND. HOWEVER STILL SOME UNCERTAINTY GIVEN THE PERSISTENT WET TREND OFF THE OPERATIONAL GFS SOLUTIONS AND A FEW OF ITS ENSEMBLE MEMBERS IN KEEPING THE CLOSED LOW SPINNING OVER THE CAROLINAS. THIS SCENARIO EVENTUALLY TAPS INTO MOISTURE WITH LOW PRESSURE OFFSHORE AND MAKES FOR QUITE AN ONSHORE TAP OF SHOWERS THROUGH MUCH OF THE PERIOD. SINCE THIS REMAINS AN OVERALL OUTLIER AT THIS POINT...WILL STAY CONSISTENT AND REMAIN CLOSER TO THE EARLIER 00Z CMC/12Z EC...AND GO MAINLY DRY EXCEPT FOR ISOLATED OROGRAPHIC AIDED SHOWERS SW FRIDAY...AND OVER SOUTHERN/CENTRAL SECTIONS SATURDAY INTO SUNDAY AS SOME LOW LEVEL MOISTURE RETURNS. OTHERWISE DRY WEDGE APPEARS TOO STRONG EVEN FOR LOW CLOUDS SO RUNNING PC/MOSTLY SUNNY WITH MORE CLOUDS BY THE WEEKEND. TEMPS REMAIN MILD BUT OVERALL STILL CLOSE TO SEASONAL NORMALS...MOSTLY 70S FOR HIGHS BUT COOL 50S AT NIGHT. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... AS OF 740 PM EDT SUNDAY... DETERIORIATING AVIATION CONDITIONS THIS TAF VALID PERIOD. A WEDGE OF MOIST...COOL AIR IS IN THE PROCESS OF DEVELOPING ACROSS THE CWA AS A LARGE AREA OF HIGH PRESSURE SLIDES FROM THE EASTERN GREAT LAKES TOWARD NEW ENGLAND. CLOUDS HAVE BEEN ON THE INCREASE ALL AFTERNOON AND CIGS ARE BEGINNING TO LOWER INTO THE MVFR RANGE ALONG THE EAST FACING SLOPES OF THE BLUE RIDGE. EXPECT CLOUD COVER TO CONTINUE TO INCREASE OVERNIGHT TO ENCOMPASS THE ENTIRE CWA WITH CIGS LOWERING MOSTLY INTO THE LOW END OF THE MVFR CATEGORY...BUT IFR AT THE HIGHER ELEVATIONS...KBCB/KBLF...AND EVENTUALLY MOST SITES BY 12Z MON. WEDGE WILL PERSIST MON...THUS LITTLE TO NO IMPROVEMENT IS EXPECTED THROUGH THE DAY. VISIBILITIES WILL TEND TO BE A LITTLE MORE DIFFICULT TO PREDICT. RADIATIONAL FOG WILL NOT BE AN ISSUE TONIGHT...NOT EVEN AT LWB. HOWEVER...IN SOME LOCATIONS WHERE CIGS DROP TO LOW END IFR OR INTO THE LIFR CATEGORY...VSBYS WILL ALSO BECOME IFR OR WORSE. MOSTLY EXPECTING MVFR CIGS IN -RA...-DZ...AND BR. WINDS...IF NOT ALREADY...BECOMING NE-ENE 5-7KTS THROUGH THE TAF VALID PERIOD...EXCEPT ESE 6-8KTS KBLF. MEDIUM CONFIDENCE IN CIGS THROUGHOUT THE TAF VALID PERIOD. MEDIUM CONFIDENCE IN VSBYS THROUGHOUT THE TAF VALID PERIOD. MEDIUM TO HIGH CONFIDENCE IN WIND SPEED/DIRECTION THROUGH THE TAF VALID PERIOD. EXTENDED AVIATION DISCUSSION... THE WEDGE WILL GRADUALLY DISSIPATE BY MIDWEEK ALLOWING CONDITIONS TO RETURN TO VFR FOR MID/LATE WEEK. SOME FORECAST MODELS INDICATE THAT LOW PRESSURE MAY RETROGRADE WESTWARD FROM THE EAST COAST LATE IN THE WEEK BRINGING CLOUDS AND PRECIPITATION...BUT CONFIDENCE IS LOW AT THIS TIME AS SEVERAL MODELS DO NOT SHOW THIS POSSIBILITY...RATHER KEEPING THE SYSTEM FURTHER EAST AND OFF THE COAST AND WITH HIGH PRESSURE OVER OUR REGION. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...JH/PM NEAR TERM...DS/KK SHORT TERM...JH LONG TERM...JH AVIATION...KK/RAB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
215 PM CDT SAT SEP 19 2015 .SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT) ISSUED AT 215 PM CDT SAT SEP 19 2015 HIGH PRESSURE OVER THE CENTRAL PLAINS INTO THE UPPER MISSISSIPPI RIVER VALLEY REGION WAS PRODUCING A PICTURE PERFECT AUTUMN-LIKE DAY ACROSS THE FORECAST AREA WITH SUNNY SKIES AND COMFORTABLY COOL TEMPERATURES IN THE 65-70 DEGREE RANGE. CENTER OF THIS HIGH PRESSURE DRIFTS SLOWLY EAST TOWARD EASTERN IA/WESTERN IL TONIGHT. THIS SETS UP A VERY LIGHT SOUTH/SOUTHWEST SURFACE WIND FLOW ACROSS THE FORECAST AREA....GENERALLY 5 TO 10 MPH. CONCERN WILL BE HOW MUCH THE WIND DECOUPLES IN THE RIVER VALLEYS/BOG COUNTRY OF CENTRAL WI FOR FOG DEVELOPMENT POTENTIAL. RAP BUFKIT DEPICTING FAIRLY LIGHT WINDS IN THE 5-10KT RANGE ALL THE WAY UP TO 500MB WHILE THE NAM SHOWS WINDS OF 10-15KT FROM 300 FEET AND ABOVE. WHILE THE RAP WOULD BE MORE CONDUCIVE FOR DECOUPLING/FOG...THE NAM IS TOO WINDY. BESIDE THE WIND...ANOTHER NEGATIVE FACTOR FOR FOG DEVELOPMENT WILL BE A BATCH OF CIRRUS ASSOCIATED WITH AN UPPER LEVEL TROUGH MOVING INTO THE AREA. IF CIRRUS IS THICK ENOUGH...THIS MAY SHUT DOWN FULL RADIATIONAL COOLING POTENTIAL NEEDED FOR FOG. HAVE TO BELIEVE THERE WILL BE SOME DECOUPLING IN THE RIVER VALLEYS/BOG COUNTRY OF CENTRAL WI FOR AT LEAST PATCHY FOG...SO WILL STICK WITH THIS FOR NOW AND LET THE EVENING FORECASTER ASSESS FURTHER. OTHERWISE...PLAN ON COOL OVERNIGHT LOWS IN THE LOWER 40S ACROSS THE SANDY/BOG COUNTRY OF CENTRAL WI...AND MIDDLE TO UPPER 40S ELSEWHERE. TEMPERATURES SHOULD REBOUND NICELY TO RIGHT AROUND SEASONAL NORMALS SUNDAY AS HIGHS TOP OFF IN THE UPPER 60S TO THE MIDDLE 70S UNDER MOSTLY SUNNY SKIES WITH LIGHT SOUTHERLY WINDS. LOOK FOR THESE LIGHT SOUTHERLY WINDS TO CONTINUE THROUGH SUNDAY NIGHT UNDER MOSTLY CLEAR SKIES WITH OVERNIGHT LOWS IN THE MIDDLE 40S TO THE MIDDLE 50S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 215 PM CDT SAT SEP 19 2015 SEASONABLY WARM/SOMEWHAT BREEZY MONDAY ON TAP AS HIGH PRESSURE DRIFTS INTO THE GREAT LAKES REGION AND COLD FRONT APPROACHES FROM SOUTHERN CANADA/NORTHERN PLAINS. UNDER MOSTLY SUNNY SKIES...PLAN ON HIGHS IN THE LOWER/MIDDLE 70S. FOR MONDAY NIGHT INTO TUESDAY...WILL BE WATCHING THAT COLD FRONT SLOWLY DRIFT SOUTHEAST INTO THE AREA. MODELS SHOWING NARROW BAND OF WEAK 850MB MOISTURE TRANSPORT/BETTER RAIN CHANCES STAYING MAINLY NORTH OF OUR AREA. THERE WILL BE SLIGHT CHANCE OF SHOWERS/ISOLATED THUNDER MAINLY FROM PORTIONS OF SOUTHEAST MN INTO NORTHERN WI ON THE EASTERN PERIPHERY OF THIS MOISTURE TRANSPORT AND WHERE NAM BUFKIT INDICATING CAP MAY BE WEAK ENOUGH TO RELEASE SOME CONVECTION. OTHERWISE...LOOK FOR HIGHS TUESDAY AGAIN WELL INTO THE 70S. FOR TUESDAY NIGHT THROUGH THURSDAY...THE LATEST GFS/ECMWF SHOW A WEAK MID-LEVEL TROUGH PROGRESSING EAST FROM THE NORTHERN PLAINS TOWARD THE UPPER MISSISSIPPI RIVER REGION. THE ECMWF WASHES THIS TROUGH OUT WHILE THE GFS MAINTAINS IT AS IT DRIFTS ACROSS THE REGION. RESULT IS LOW-END SHOWER/THUNDER CHANCES DURING THIS PERIOD. LATEST ECMWF/GFS SHOWING MASSIVE RIDGING OVER THE CENTRAL CONUS/UPPER MISSISSIPPI RIVER VALLEY REGION FRIDAY AND SATURDAY. AS A RESULT...DRIED THIS PERIOD OUT. OTHERWISE...TEMPERATURES FOR WEDNESDAY THROUGH SATURDAY LOOK TO BE CLOSE TO SEASONAL NORMALS IN THE UPPER 60S TO THE UPPER 70S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1240 PM CDT SAT SEP 19 2015 MOSTLY SUNNY SKIES AND LIGHT NORTHWEST WIND WILL CONTINUE AT KRST/KLSE THROUGH THE AFTERNOON. WINDS WILL SHIFT TO THE SOUTH- SOUTHWEST LATE THIS EVENING AND OVERNIGHT AS SURFACE HIGH PRESSURE OVER OMAHA NE MOVES TOWARD CHICAGO IL. BESIDES SOME INCREASING CIRRUS OVERHEAD TONIGHT...A DRY LOW-MID LEVEL AIR MASS WILL RESULT IN CLEAR SKIES. WESTERLY WINDS AROUND 15 KTS ABOVE THE NOCTURNAL INVERSION WILL PROHIBIT FOG AT KRST. HOWEVER...THE LIGHT WIND LAYER MAY BE DEEP ENOUGH AT KLSE FOR SOME PATCHY FOG. WILL INTRODUCE BCFG AND A LOW SCATTERED CLOUD DECK FROM 20.10Z UNTIL 20.14Z...BUT STILL EXPECT VFR CONDITIONS AT THIS TIME. SUNDAY WILL BE MOSTLY SUNNY WITH LIGHT SOUTHERLY WINDS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...DAS LONG TERM...DAS AVIATION...ROGERS
AREA FORECAST DISCUSSION
NWS TUCSON AZ
923 PM MST SUN SEP 20 2015 .SYNOPSIS...VERY LIMITED THUNDERSTORM ACTIVITY FOR THIS EVENING AND MOST OF THE NIGHT. THAT WILL CHANGE A GREAT DEAL BY MONDAY AND TUESDAY AS DEEP TROPICAL MOISTURE COMBINES WITH A PACIFIC LOW TO BRING NUMEROUS SHOWERS AND SOME THUNDERSTORMS TO THE AREA. THE POTENTIAL IS INCREASING FOR HEAVY RAINFALL MONDAY AFTERNOON INTO TUESDAY WITH SOME FLOODING CONCERNS...ESPECIALLY FROM TUCSON WESTWARD AND IN HIGHER TERRAIN...WITH A FLASH FLOOD WATCH IN EFFECT FOR MOST OF THE AREA. DRY CONDITIONS WILL RETURN DURING THE LATTER PART OF THE WEEK. && .DISCUSSION...WATER VAPOR IMAGERY...21/00Z UPPER-AIR PLOTS AND RECENT MODEL DATA SHOW AN UPPER LOW WELL OFF THE CENTRAL BAJA COAST...WITH TROPICAL DEPRESSION SIXTEEN-E LOCATED AT 26.2 DEGS N; 113.6 DEGS W...OR ABOUT 135 MILES W OF LORETO MEXICO...AS OF 9 PM MDT (8 PM MST). MOVEMENT OF THIS SYSTEM IS TO THE NORTH AT 15 MPH... WITH MAXIMUM SUSTAINED WINDS OF 35 MPH. BASED ON THIS LATEST ADVISORY FROM THE HURRICANE CENTER...THE DEPRESSION WILL CROSS THE CENTRAL BAJA PENINSULA OVERNIGHT AND THEN BE IN THE PROCESS OF ENTERING INTO THE NORTH CENTRAL GULF OF CALIFORNIA SHORTLY BEFORE SUNRISE MONDAY. BY LATE MONDAY AFTERNOON OR EARLY EVENING THE DEPRESSION WILL BE IN THE PROCESS OF CROSSING THE INTERNATIONAL BORDER FROM NORTH CENTRAL SONORA MEXICO INTO SOUTH CENTRAL ARIZONA. THE LATEST IR SATELLITE IMAGERY INDICATES CLOUD TOPS TEMPS OVER THE NORTHERN GULF OF CALIFORNIA ARE AT MINUS 84 DEGS CELSIUS AS OF 03Z. EARLIER THESE READINGS WERE SLIGHTLY COOLER AND COVERED A LARGER AREA...BUT STILL QUITE RESPECTABLE. AS THE SYSTEM CONTINUES TO MAKE PROGRESS TO THE NORTH...EXPECT CONDITIONS TO CONTINUE TO DETERIORATE DURING THE OVERNIGHT HOURS AND TOWARDS DAYBREAK WITH THE BULK OF THE PRECIPITATION OCCURRING DURING MUCH OF THE DAY ON MONDAY AND CONTINUING INTO MONDAY NIGHT...WITH SHOWERS SLOWLY BEGINNING TO DECREASE TUESDAY...BUT STILL IN THE SCATTERED TO NUMEROUS CATEGORY BEFORE FINALLY SHUTTING DOWN TO ONLY SLIGHT CHANCES BY WEDNESDAY. THAT SAID...CURRENTLY SEEING MAINLY HIGH LEVEL CIRRUS CLOUDS SPREADING INTO SOUTHERN ARIZONA CURRENTLY...BUT WE SHOULD SEE AN INCREASE IN MID AND LOW LEVEL CLOUDINESS THROUGH THE NIGHT AND ESPECIALLY TOWARD MORNING. THE LATEST HRRR MODEL SHOWS SOME LIGHT SHOWERS BEGINNING TO ENTER MY FORECAST AREA OVER SOUTHERN PARTS OF SANTA CRUZ AND COCHISE COUNTIES BY AROUND 10Z THEN CONTINUING TO SPREAD NORTH AND INTENSIFY...WITH NEARLY ALL OF MY FORECAST AREA AFFECTED BY AT LEAST LIGHT TO MODERATE SHOWERS BEFORE NOON. 00Z RUN OF THE U OF A WRF/NAM SHOWED A SIMILAR SOLUTION . THAT SAID...THE INHERITED POP FORECAST FOR THE REST OF THE NIGHT SEEMS REASONABLE...SO NO CHANGES ARE PLANNED AT THIS TIME. THE POTENTIAL FOR HEAVY RAIN CONTINUES WITH THIS SYSTEM WITH STORMS TOTALS RANGING FROM AROUND 1.5 TO 2.25 INCHES FROM TUCSON WEST AND NORTHWEST...WITH HIGHER VALUES OVER THE MOUNTAINS. LESSER TOTALS FOR AREAS EAST (MAINLY COCHISE COUNTY) SINCE THOSE AREAS WILL BE FARTHER REMOVED FROM WHERE THE CENTER OF THE CIRCULATION AND HEAVIEST RAIN IS EXPECTED TO OCCUR. THAT SAID...A FLASH FLOOD WATCH WILL BE IN EFFECT FROM 5 AM MONDAY AND CONTINUE THROUGH 5 PM TUESDAY. AS OF 03Z (8 PM MST)...TEMPERATURES RANGED FROM THE LOWER 70S TO THE UPPER 80S...WITH THE TUCSON INTL AIRPORT REPORTING A TEMP OF 88 DEGS...AFTER AN AFTERNOON HIGH OF 95 DEGS. BASED ON LATEST MODEL DATA AND THE FACT THAT CLOUDINESS AND EVENTUAL MOISTURE WILL MOVE INTO THE REGION...I WILL INCREASE LOW TEMPS A BIT FOR OVERNIGHT... MAINLY ALONG THE BORDER WITH MEXICO. FOR DETAILS REGARDING THE FORECAST BEYOND TONIGHT AND MONDAY... PLEASE REFER TO THE PREVIOUS DISCUSSION BELOW. && .AVIATION...VALID THRU 22/06Z. INCREASING CLOUDS AND SHOWERS FROM THE SOUTH TONIGHT INTO MONDAY AS TROPICAL MOISTURE PUSHES IN FROM THE SOUTH. MVFR CONDITIONS POSSIBLE WITH SHOWERS OR THUNDERSTORMS BY LATER TONIGHT...MAINLY NEAR KOLS. INCREASING AND SPREADING AREA WIDE MONDAY. NORMAL DIURNAL WIND TRENDS OVERNIGHT...WITH SOUTHERLY WINDS INCREASING MONDAY. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...ISOLATED THUNDERSTORMS WILL OCCUR MAINLY SOUTH OF TUCSON TODAY. INCREASING MOISTURE WILL THEN PRODUCE PERIODS OF SHOWERS...HEAVY AT TIMES...WITH EMBEDDED THUNDERSTORMS MONDAY INTO TUESDAY. A SLIGHT CHANCE OF THUNDERSTORMS WILL CONTINUE WEDNESDAY FOLLOWED BY DRY CONDITIONS ACROSS MUCH OF THE AREA THURSDAY INTO SATURDAY. && .PREV DISCUSSION...TROPICAL SYSTEMS...EVEN LESS WELL DEFINED ONES LIKE THE CURRENT FEATURE ABOUT 175 MILES WEST OF THE SOUTHERN TIP OF BAJA...TYPICALLY FOCUS ELEVATED PRECIPITABLE WATER AMOUNTS IN EXCESS OF 2 INCHES NEAR THE CORE AND EASTERN FLANK OF THE SYSTEM. CURRENTLY CIRA LAYERED PRECIPITABLE WATER TOTALS ARE SHOWING A VERY LARGE AREA FROM THE CENTRAL GULF OF CALIFORNIA TO THE SOUTHERN GULF...AS WELL AS THE PACIFIC SIDE OF THE BAJA PENINSULA OF VALUES NEAR OR ABOVE 3 INCHES. I`M NOT SURE IF I`VE SEEN SUCH A LARGE AREA NEAR OR IN EXCESS OF 3 INCHES BEFORE. THE BOTTOM LINE THOUGH...IS THAT THIS IS DIFFERENT THAN LINDA EARLIER THIS MONTH IN EVEN MORE IMPORTANT WAYS. WE HAVE A STRONGER LOW LEVEL FLOW DEVELOPING ON THE ELONGATED EASTERN FLANK OF THE POORLY DEFINED CENTER. H8 WINDS IN THE 35KT RANGE OUT OF THE SOUTH PUSHING INTO PIMA COUNTY LATE MONDAY AFTERNOON AND MONDAY EVENING AS THE REMNANT LOW PUSHES INTO SOUTHERN ARIZONA. IN ADDITION...WE WILL HAVE INTERACTION WITH A FAIRLY DECENT LOW CURRENTLY OFF THE SOUTHERN CALIFORNIA AND NORTHERN BAJA COAST THAT WILL PROVIDE ADDITIONAL DYNAMICS AND A FAVORABLE UPPER LEVEL DIFFLUENT FIELD MONDAY NIGHT INTO TUESDAY. SO WE HAVE WHAT MAY END UP BEING RECORD AMOUNTS OF MOISTURE...AND WE HAVE MULTIPLE TRIGGERS TO TAKE ADVANTAGE OF IT. THE FORECAST MOISTURE CONVERGENCE FIELDS ARE...TO SAY THE LEAST...VERY IMPRESSIVE ACROSS SOUTHERN ARIZONA MONDAY AFTERNOON AND MONDAY NIGHT. IT WILL BE A VERY EFFICIENT PRECIP PROCESS. CONSERVATIVE STORM TOTAL QPF VALUES FOR MONDAY INTO TUESDAY RANGE FROM ABOUT 1 INCH IN EASTERN AREAS...TO 2.5 INCHES IN WESTERN PIMA COUNTY WITH ISOLATED HIGHER AMOUNTS. RAINFALL AMOUNTS IN EXCESS OF 3 INCHES ARE EXPECTED IN SOME MOUNTAIN LOCATIONS. A FLASH FLOOD WATCH IS IN EFFECT FOR MOST OF THE AREA MONDAY AND TUESDAY. THE BEST AREA OF WIDESPREAD PRECIP AS WELL AS THE SHEARING REMNANT LOW WILL HAVE LIFTED NORTH AND NORTHEAST OF OUR AREA BY TUESDAY MORNING. THEN THE LOW OFF THE SOUTHERN CALIFORNIA COAST WILL COME INTO PLAY BY MID DAY TUESDAY WITH DEEP RESIDUAL MOISTURE AND FAVORABLE DYNAMICS FOR STRONG THUNDERSTORMS TUESDAY AFTERNOON. A DEEP WESTERLY TO SOUTHWESTERLY FLOW WILL START TO DRY THINGS OUT BY WEDNESDAY AFTERNOON. A RIDGE BUILDING OVER THE AREA THURSDAY AND FRIDAY WILL QUICKLY PUSH TEMPERATURES BACK WELL ABOVE AVERAGE FOR THE END OF THE WEEK. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DISCUSSION...MOLLERE PREVIOUS DISCUSSION...MEYER/RASMUSSEN VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1149 PM CDT SUN SEP 20 2015 .UPDATE... ISSUED AT 853 PM CDT SUN SEP 20 2015 Another quiet but cool night across central and southeast Illinois as high pressure remains in control of the local weather. Light winds, mostly clear skies, and a dry airmass should allow overnight temperatures to fall into the 40s again in many areas. Only plan minor tweaks to the hourly nighttime grids for the latest trends. && .SHORT TERM...(TONIGHT) ISSUED AT 244 PM CDT SUN SEP 20 2015 Broad expanse of high pressure set up in the Midwest with the ridge axis stretched from the eastern Great Lakes back into Missouri. A small shortwave on sat imagery to the northwest forecast in the HRRR to pass to the north this evening. Dominant high pressure should give Central Illinois another quiet night. Winds will become light and variable under the ridge, with temps dropping into the upper 40s and lower 50s. Not much to discuss in terms of weather, but will mention the potential for very patchy light fog/vis drops. However, leaving it out of the grids as the afternoon dewpoints are dropping several degrees as the llvls mix out in the day time heating. .LONG TERM...(Monday THROUGH Sunday) ISSUED AT 244 PM CDT SUN SEP 20 2015 Seeing a consistent signal in the 12z models for a dry week in the extended forecast across central and southeast IL. High pressure centered over the Great Lakes and extending southwest across Illinois will gradually shift to the east over the first half of this week. The southwest end of the surface ridge looks to remain across central and southern Illinois during that time, keeping seasonable and dry conditions across our forecast area. A cold front will approach NW Illinois on Tuesday, reaching eastern Iowa by 00z Wed/7pm Tues. The front is projected to stall out in that general area for the rest of the week, as a ridge remains entrenched across the eastern states due to the blocking effects of a low pressure system off the central East Coast. The end result will be some increase in cloud cover for our areas west of I-55 for the last half of the week, but plenty of dry air above and below the cloud layer will keep precip at bay. Low pressure progressing from the SW states will move northeast along the front later this week, reaching the Upper Mississippi River Valley Thursday into Friday. That will bring another period of increased cloud cover for our western counties, but no rain. That low is expected to dissipate on Friday as it passes by to the north of IL, with expanding high pressure across Illinois in it`s wake. That will keep dry conditions in the forecast through next weekend. As for temperatures this week, the chilly air will remain across our area into Tuesday. However, southerly flow will develop ahead of the approaching cold front, bring warmer air to our area the rest of the week. Highs will reach back into the lower 80s from Wednesday to Sunday. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Monday NIGHT) ISSUED AT 1146 PM CDT SUN SEP 20 2015 High pressure will continue to dominate the weather across the central Illinois terminals through the 06Z TAF valid time. VFR conditions will prevail, with generally light winds and minimal cloud cover. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Bak SHORT TERM...HJS LONG TERM...Shimon AVIATION...Bak
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
358 AM CDT MON SEP 21 2015 ...Updated Long Term Section... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 1238 AM CDT MON SEP 21 2015 Main question is when/how many counties to go with a Dense Fog Advisory. We will likely be issuing one over the coming hours once we see some visibility observations drop. Abundant low level moisture with light southeast winds and clear skies are providing the necessary backdrop for dense fog formation, especially at the edge of the current stratus deck, which as of 0530z extended from roughly Meade to just south of Hays (there was a narrow break from Dodge City to Ashland). Temperatures today will be a real challenge, and with all this moisture in place along with a slow erosion of the expected fog/low stratus, we will probably only see temperatures topping out in the lower to mid 80s northeast of a Dighton to Dodge City to Coldwater line. Farther southwest, the temperature forecast will be unchanged with lower 90s still expected. The WRF-ARW was followed, which did a fairly good job of depicting yesterday`s cool bubble across portions of south-central Kansas. .LONG TERM...(Tuesday THROUGH Sunday) ISSUED AT 357 AM CDT MON SEP 21 2015 The global models are coming into slightly better agreement regarding the mid-week increase in precipitation chances. The ECMWF model is still the most developed, maintaining the most coherent mid level potential vorticity anomaly as the subtropical low meanders into western Kansas by Wednesday Night. The Canadian GEM is next in line and follows closer the ECMWF solution than does the GFS. As a result, the Canadian GEM and the ECMWF solutions offer the best scenario for sustained precipitation chances from early to midday Wednesday lasting into Thursday Night. There will likely be several rounds with a few breaks within the smaller scale episodes of precipitation. This does not look like a situation where severe weather will be much of a risk. Deep subtropical moisture and the lack of lower-mid tropospheric frontogenesis will both be negatives as far as severe weather potential is concerned... both limiting CAPE. As far as temperatures go, the daytime temperatures will be trending downward from previous forecast, and do not be surprised to see further decrease in forecast highs, especially Thursday. The ECMWF is quite cool on Thursday keeping all of western Kansas in the 60s. We will see if the Canadian GEM and the GFS follow suit in future runs. The subtropical disturbance will continue to wallow aimlessly across the western Kansas until it spins itself out...as the main polar jet will be way off to the north in Canada. Pronounced lower tropospheric warming will be confined to areas north of the Central High Plains it would appear, as the subtropical entity nearby will keep temperatures in check given the absence of any downslope momentum over western Kansas amidst a fairly deep, moist troposphere. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Monday NIGHT) ISSUED AT 1238 AM CDT MON SEP 21 2015 Dense fog is likely to cause some aviation problems this morning. The best time frame for dense fog will be 10-14z, or a 4-5 hour window as abundant Gulf of Mexico moisture continues to move in on southeast winds. There is pretty high confidence in the fog forecast with pretty aggressive visibility restriction including run-to-run continuity from the HRRR model as well as the WRF-ARW, WRF-NNMB, and NAM12 solutions. IFR category will probably continue through midday (17z or so) especially up around HYS where it may even persist into the afternoon hours. There should be a fairly rapid clearing once the low stratus does start to scatter out. No wind shifts are forecast during this TAF period with south to southeast winds continuing. && .PRELIMINARY POINT TEMPS/POPS... DDC 85 64 91 65 / 0 0 10 20 GCK 89 63 92 64 / 0 0 20 30 EHA 93 65 90 64 / 0 0 30 40 LBL 91 65 92 65 / 0 0 10 20 HYS 81 63 92 66 / 0 0 10 20 P28 85 64 92 67 / 0 0 0 10 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Umscheid AVIATION...Umscheid
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
1239 AM CDT MON SEP 21 2015 ...Updated Aviation and Short Term Section... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 1238 AM CDT MON SEP 21 2015 Main question is when/how many counties to go with a Dense Fog Advisory. We will likely be issuing one over the coming hours once we see some visibility observations drop. Abundant low level moisture with light southeast winds and clear skies are providing the necessary backdrop for dense fog formation, especially at the edge of the current stratus deck, which as of 0530z extended from roughly Meade to just south of Hays (there was a narrow break from Dodge City to Ashland). Temperatures today will be a real challenge, and with all this moisture in place along with a slow erosion of the expected fog/low stratus, we will probably only see temperatures topping out in the lower to mid 80s northeast of a Dighton to Dodge City to Coldwater line. Farther southwest, the temperature forecast will be unchanged with lower 90s still expected. The WRF-ARW was followed, which did a fairly good job of depicting yesterday`s cool bubble across portions of south-central Kansas. .LONG TERM...(Monday NIGHT THROUGH Sunday) ISSUED AT 102 PM CDT SUN SEP 20 2015 Precip will remain generally absent through Tuesday night as medium range models continue to indicate an upper level ridge of high pressure building northeast across the Western High Plains. Although a prevailing southerly flow will draw some moisture back north into the area, a lack of significant instability combined with a persistent weak flow aloft will limit any precip chances through Tuesday night. However, precip chances will return to western Kansas Wednesday as an upper level trough of low pressure is projected to lift northeast across the Desert Southwest into the Western High Plains while accompanied by a feed of tropical moisture. Although less than robust, the flow aloft is expected to strengthen somewhat while a developing surface low lee of the Rockies continues to enhance a southerly flow across western Kansas. This will occur ahead of a zone of increasing surface convergence associated with the lee side trough axis. Chances for precip will linger into Thursday as the upper level shortwave is slow to lift further to the northeast. Little change is expected to the general air mass across western Kansas Monday into Tuesday, so look for highs to reach the lower to mid 90s(F) again Tuesday afternoon. Although the southerly flow will persist through Wednesday, increasing cloud cover and precip will likely keep high temperatures down a bit Wednesday afternoon. Same can be said for Thursday. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Monday NIGHT) ISSUED AT 1238 AM CDT MON SEP 21 2015 Dense fog is likely to cause some aviation problems this morning. The best time frame for dense fog will be 10-14z, or a 4-5 hour window as abundant Gulf of Mexico moisture continues to move in on southeast winds. There is pretty high confidence in the fog forecast with pretty aggressive visibility restriction including run-to-run continuity from the HRRR model as well as the WRF-ARW, WRF-NNMB, and NAM12 solutions. IFR category will probably continue through midday (17z or so) especially up around HYS where it may even persist into the afternoon hours. There should be a fairly rapid clearing once the low stratus does start to scatter out. No wind shifts are forecast during this TAF period with south to southeast winds continuing. && .PRELIMINARY POINT TEMPS/POPS... DDC 64 92 65 87 / 0 0 10 40 GCK 63 93 64 87 / 0 0 20 40 EHA 64 91 64 86 / 0 10 20 30 LBL 64 93 65 88 / 0 0 20 40 HYS 64 93 66 89 / 0 0 20 40 P28 65 93 67 89 / 0 0 10 30 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Umscheid LONG TERM...JJohnson AVIATION...Umscheid
AREA FORECAST DISCUSSION
NWS JACKSON KY
149 AM EDT MON SEP 21 2015 .UPDATE... ISSUED AT 800 PM EDT SUN SEP 20 2015 UPDATED FORECAST TO REFINE THE SKY COVER BASED ON THE LATEST HI RES MODELS. HRRR IS BACKING OFF ON SHOWERS MAKING INTO OUR FAR EAST LATE TONIGHT. HOWEVER...STILL OPTING TO HOLD ONTO A SLIGHT CHANCE OF A SHOWER FOR PIKE/HARLAN/LETCHER COUNTIES. OTHERWISE...REST OF THE AREA WILL REMAIN DRY. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 400 PM EDT SUN SEP 20 2015 A COLD FRONT DISSIPATED AS IT MOVED THROUGH OUR REGION LAST EVENING. SURFACE WINDS OUT OF THE NW BEHIND THE FRONT INITIALLY BEGAN TO CARRY IN DRIER AIR. HOWEVER...WITH THE DEMISE OF THE BOUNDARY AND WINDS EVENTUALLY VEERING TOWARD THE NE...THE DRIER AIR HAS HAD TROUBLE MAKING IT ALL THE WAY INTO OUR AREA. LOW CLOUDS HAVE LINGERED ALL DAY NEAR THE BORDER WITH TN AND VA. WITH LOW LEVEL MOISTURE NEARBY A MID/UPPER LEVEL TROUGH DROPPING SOUTHEAST INTO THE REGION IS EXPECTED TO LEAD TO A RESURGENCE OF CLOUDS AND POSSIBLY SOME SHOWERS FOR PORTIONS OF THE CENTRAL APPALACHIANS TONIGHT INTO MONDAY. THIS SHOULD MAINLY BE TO THE EAST OF THE JKL FORECAST AREA...BUT COULD CLIP THE EASTERN TIP OF KY. THIS WOULD PROVIDE A BIT OF INHIBITION FOR TEMPERATURES TO FALL OVERNIGHT AND TO RISE ON MONDAY IN THE EASTERN PART OF THE AREA. MEANWHILE...IN THE WEST SKIES SHOULD BE CLEAR TO PARTLY CLOUDY AND MORNING LOWS A BIT COOLER AND HIGHS ON MONDAY A BIT WARMER WHEN COMPARED TO THE EAST. THE EFFECTS OF THE MID/UPPER LEVEL WAVE ARE EXPECTED TO SHIFT SLIGHTLY EASTWARD MONDAY NIGHT...LEAVING US WITH DRY WEATHER UNDER CLEAR TO PARTLY CLOUDY SKIES AREA WIDE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 400 PM EDT SUN SEP 20 2015 THE EXTENDED PORTION OF THE FORECAST BEGINS ON TUESDAY WITH THE UPPER LEVEL PATTERN DEVELOPING INTO A BROAD RIDGE OVER THE ENTIRE CONUS. THE JET REMAINS POSITIONED NORTH ALONG THE CANADIAN BORDER WITH MOST OF THE UPPER LEVEL WAVES PASSING NORTH OF THE FORECAST AREA FOR MUCH OF THE EXTENDED PERIOD. HOWEVER...AN UPPER LOW BECOMING CUT OFF FROM THE UPPER LEVEL FLOW UNDER THE RIDGE WILL MEANDER THROUGH THE FRONT RANGE AND INTO THE SOUTHERN PLAINS. ALSO DURING THIS TIME...A CUT OFF LOW IN THE SOUTHEAST THAT MEANDERS JUST OFF THE FL PANHANDLE WILL THEN EVENTUALLY DRIFT NORTH AGAIN AND POTENTIALLY BRING SOME UPPER LEVEL SUPPORT INTO EASTERN KENTUCKY BY THE END OF THE EXTENDED. NEAR THE SURFACE...HIGH PRESSURE WILL BE THE DOMINANT WEATHER FEATURE THROUGH THE EXTENDED FORECAST PERIOD. WITH THE EXCEPTION OF THE WEAK SURFACE BOUNDARY ALONG THE APPALACHIAN RANGE AND A WEAK UPPER LEVEL DISTURBANCE PROVIDING SOME WEAK FORCING FOR AFTERNOON SHOWER DEVELOPMENT ON TUESDAY...WEDNESDAY THROUGH FRIDAY SHOULD REMAIN DRY AT THIS POINT WITH THE SURFACE HIGH QUITE STRONG ENOUGH TO KEEP ANY SURFACE FORCING FROM MAKING IT INTO THE AREA. THE ONLY EXCEPTION WILL BE A SLIGHT CHANCE OF PRECIP THAT DEVELOPS WITH THE ASSIST OF THE HIGHER TERRAIN IN THE EAST. IN FACT...WILL TREND BELOW THE SUPER BLEND SOLUTION THROUGH SATURDAY. THE CURRENT PATTERN CERTAINLY DOES SEEM TO TREND DRIER AND AS IS THE TIME OF THE YEAR AS WELL. SO WENT BELOW SUPERBLEND VALUES AND THIS WAS AGREED BY NEIGHBORING OFFICES AS WELL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 148 AM EDT MON SEP 21 2015 ACCORDING TO THE LATEST IR SATELLITE IMAGERY...AS WELL AS OBSERVATIONS ACROSS THE REGION...ONLY HIGH LEVEL CLOUD COVER REMAINS ACROSS THE CWA. IT IS ALSO SHOWING A VERY DEFINED BACK EDGE TO THIS UPPER LEVEL CLOUD DECK AS IT CONTINUES TO DRIFT SLOWLY SE ACROSS KY. AS SUCH...IT SHOULD POSE VERY LITTLE IMPACT THROUGHOUT THE NIGHT. HOWEVER...NOT GOING TO RULE SOME MVFR CLOUDS SHIFTING BACK INTO THE FAR EASTERN CWA AND POSSIBLY AFFECTING KSJS. ANY FOG WHICH FORMS ACROSS THE REGION WILL LIKELY BE CONFINED TO THE VALLEYS...SO DID NOT MENTION ANY IMPACTS FOR THE TAF SITES AT THIS TIME. FOR TOMORROW...LATEST FORECAST SOUNDINGS ARE SHOWING SOME DIURNAL CU DEVELOPMENT IN THE UPPER MVFR TO LOWER END VFR RANGE. CLOUDS WILL BE CONTINUE TO BE THICKEST OVER THE FAR EASTERN PORTION OF THE STATE...WHERE SOME BKN MVFR CIGS MAY CONTINUE AT TIMES ACROSS KSJS. OTHERWISE...WINDS SHOULD REMAIN LIGHT AND GENERALLY FROM THE NORTH TO NORTHEAST NEAR THE SURFACE. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KAS SHORT TERM...HAL LONG TERM...SHALLENBERGER AVIATION...JMW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
521 AM EDT MON SEP 21 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 507 AM EDT MON SEP 21 2015 WV IMAGERY AND RAP ANALYSIS INDICATED ZONAL MID/UPPER LEVEL FLOW FROM THE PAC NW INTO NRN ONTARIO AND A WEAK TROUGH OVER THE GREAT LAKES. A VIGOROUS SHRTWV TROUGH WAS MOVING THROUGH SRN ALBERTA. AT THE SFC...INCREASING SRLY FLOW PREVAILED ACROSS THE UPPER MS VALLEY INTO THE WRN LAKES BETWEEN HIGH PRES OVER NEW ENGLAND AND A TROUGH EXTENDING INTO THE PLAINS FROM LOW PRES OVER SRN SASK/MANITOBA. THE WAA PATTERN SUPPORTED ONLY PATCHY MID CLOUDS FROM WRN LAKE SUPERIOR THROUGH WI. TODAY...ABUNDANT SUNSHINE AND MIXING THROUGH 850 MB TEMPS CLIMBING INTO THE 10C-12C RANGE WILL SUPPORT MAX TEMPS IN THE LOW TO MID 70S. SLIGHTLY WARMER CONDITIONS WILL AGAIN PREVAIL IN DOWNSLOPE FLOW LOCATIONS ALONG LAKE SUPERIOR. FCST WINDS THROUGH THE MIDDLE AND UPPER PORTION OF THE MIXED LAYER SUPPORT WIND GUSTS INTO THE 20-25 MPH RANGE WITH SOME 25-30 MPH GUSTS OVER THE WEST. TONIGHT...AS THE VIGOROUS SHRTWV TROUGH AND ASSOCIATED DEEP SFC LOW LIFTS FROM NRN MANITOBA TO HUDSON BAY A COLD FRONT WILL BE DRAGGED THROUGH THE NRN LAKES. GIVEN THE ABSENCE OF DEEP MOISTURE...ONLY MODEST MOISTURE TRANSPORT ALONG THE FRONT AS WELL AS THE STRONGEST MID LEVEL FORCING REMAINING WELL TO THE N OVER NRN ONTARIO (SLIGHT HEIGHT RISES ARE FCST OVER THE NRN LAKES TONIGHT)...WILL CONTINUE TO MENTION ONLY LOWER END CHANCE POPS FOR SHRA/TSRA OVER NORTHWEST HALF LATE TONIGHT. MUCAPE VALUES INTO THE 500-1000 J/KG RANGE WILL SUPPORT TSRA CHANCES BUT WILL BE MARGINAL FOR THE POTENTIAL OF ANY STRONGER STORMS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 346 AM EDT MON SEP 21 2015 LIMITED CHANGES IN THE OVERALL LONG TERM FORECAST FROM 24 HOURS AGO...AS THE UPPER JET TRACKS FROM WEST TO EAST ACROSS SOUTHERN CANADA THROUGH THE LATER PART OF THIS WEEK BEFORE AMPLIFYING OVER CENTRAL CANADA FOR NEXT WEEKEND. THAT LOCATION OF THE JET WILL KEEP THE NORMAL (MIDDLE OF THIS WEEK) TO ABOVE NORMAL TEMPERATURES (THIS WEEKEND) IN PLACE THROUGHOUT THE FORECAST PERIOD. THERE ARE TWO OPPORTUNITIES FOR RAIN DURING THIS FORECAST PERIOD...WITH THE FIRST TIED TO THE COLD FRONT DROPPING SOUTHEAST ACROSS THE AREA ON TUESDAY MORNING. THE COMBINATION OF LIMITED MOISTURE AND UPPER LEVEL SUPPORT SHOULD ONLY LEAD TO ISOLATED SHOWERS DROPPING SOUTHEAST ACROSS THE CENTRAL/EASTERN U.P. AS THE FRONT MOVES THROUGH THAT AREA ON TUESDAY. DID CONTINUE TO MENTION A SLIGHT CHANCE OF THUNDER DUE TO THE THIN REGION OF WEAK INSTABILITY AHEAD OF THE FRONT. CANADIAN HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND THE FRONT AND SHOULD LEAD TO MOSTLY CLEAR SKIES OVER THE WESTERN U.P. TUESDAY AFTERNOON AND THE REST OF THE AREA ON TUESDAY NIGHT. THE NEXT OPPORTUNITY FOR RAIN WILL COME FROM BROAD WARM AIR ADVECTION DEVELOPING ON TUESDAY NIGHT IN THE MID-UPPER MISSISSIPPI VALLEY THAT WILL LIFT NORTH-NORTHEAST INTO THE WESTERN CWA ON WEDNESDAY. THERE SHOULD BE PLENTY OF MOISTURE TO WORK WITH THIS AS EXISTING MOISTURE IN THE PLAINS COMBINES WITH THE REMNANTS OF TROPICAL DEPRESSION SIXTEEN-E CURRENTLY NEAR THE BAJA PENINSULA. THE LATEST TRENDS IN THE MODELS KEEPS MUCH OF THE ENERGY FROM THE TROPICAL REMNANTS IN THE CENTRAL PLAINS...SO THE PRECIPITATION WILL BE TIED TO THAT INITIAL SURGE OF WARM AIR ADVECTION ON WEDNESDAY INTO WEDNESDAY NIGHT. THAT SURGE WILL BE OVER NORTHEAST MINNESOTA INTO NORTHWEST WISCONSIN ON WEDNESDAY MORNING AND THEN SLIDE EAST INTO WESTERN LAKE SUPERIOR AND THE WESTERN U.P. THROUGH THE DAY ON WEDNESDAY. WILL FOCUS THE HIGHEST POPS IN THAT AREA AND THEN SLOWLY DIMINISH THEM AS THE FORCING WEAKENS AND MOVES EAST ACROSS THE REST OF THE CWA WEDNESDAY NIGHT INTO THURSDAY. MODELS SHOWING PWAT VALUES RISING TOWARDS 1.5 INCHES...WHICH IS WELL ABOVE NORMAL AND LEADS TO THE POTENTIAL FOR LOCALLY HEAVY RAIN OVER WESTERN LAKE SUPERIOR AND THE WESTERN U.P WITH ANY EMBEDDED THUNDERSTORMS. A 1036MB HIGH MOVING INTO NORTHERN ONTARIO ON THURSDAY WILL EXTEND A RIDGE SOUTH TOWARDS LAKE SUPERIOR THURSDAY INTO THURSDAY NIGHT. THAT WILL SHIFT THE LOW LEVEL FLOW TO THE NORTHEAST AND START TO BRING DRIER AIR INTO THE AREA. EXPECT THE DIMINISHING UPPER LEVEL SUPPORT AND GREATER INFLUENCE OF THE HIGH TO CONTINUE INTO THURSDAY NIGHT AS THE HIGH MOVES OVER JAMES BAY. THAT SHOULD REALLY DIMINISH PRECIPITATION CHANCES HEADING INTO FRIDAY...ALTHOUGH THERE COULD BE ENOUGH LINGERING LOW LEVEL MOISTURE TO SUPPORT SOME SHOWERS OVER THE WESTERN U.P. ON THE EDGE OF THE RIDGE. AT THIS POINT...THE WEEKEND LOOKS DRY WITH THE UPPER RIDGE BUILDING OVER CENTRAL CANADA AND THE SURFACE HIGH DROPPING SOUTHEAST INTO THE NEW ENGLAND STATES. THIS WILL KEEP THE UPPER GREAT LAKES REGION UNDER THE WESTERN EDGE OF THE SURFACE RIDGE AND WITH MIXING TO 875MB TEMPS AROUND 10C ON SATURDAY WOULD SUPPORT HIGHS IN THE LOW 70S AND THEN SLIGHTLY HIGHER TEMPS ON SUNDAY WITH A LITTLE BETTER MIXING. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 143 AM EDT MON SEP 21 2015 A DRY SSW FLOW ARND HI PRES MOVING INTO THE NE STATES WL BRING VFR CONDITIONS TO ALL 3 TAF SITES THRU THE FORECAST PERIOD. AS THE PRES GRADIENT TIGHTENS EARLY THIS MRNG DURING NOCTURNAL COOLING...EXPECT SOME LLWS TO IMPACT IWD...WHERE THE PRES GRADIENT WL BE SHARPER AND THE LLJ STRONGER AT THE BASE OF THE RADIATION INVRN. AT CMX AND SAW...THE LLWS POTENTIAL SEEMS MORE MARGINAL...SO LEFT OUT OF THE FCST FOR NOW. THE ONSET OF DAYTIME HEATING/MIXING WILL RESULT IN SOME GUSTY SW WINDS BY MID/LATE MRNG. SINCE THE PRES GRADIENT WL SHARPEN EVEN MORE THIS EVNG AS A COLD FNT APRCHS FM THE W...EXPECT GUSTY WINDS TO PERSIST EVEN AFTER SUNSET. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 520 AM EDT MON SEP 21 2015 HIGH PRESSURE OVER THE LOWER GREAT LAKES WILL SLOWLY EXIT ACROSS THE NEW ENGLAND AS A LOW OVER MANITOBA DEEPENS AND LIFTS NE THROUGH HUDSON BAY TONIGHT THROUGH TUESDAY. AS A RESULT...AN INCREASING PRES GRADIENT WILL SUPPORT S WINDS IN THE 20-25 KNOT RANGE TODAY AND TONIGHT. EXPECT THE LOW TO DRAG A COLD FRONT ACROSS LAKE SUPERIOR TONIGHT THROUGH TUE. BEHIND THE LOW...HIGH PRESSURE ACROSS NORTH DAKOTA TUE MORNING WILL BUILD OVER LAKE SUPERIOR TUE AFTERNOON...BEFORE EXPANDING ACROSS NRN ONTARIO WED. A RIDGE WILL REMAIN THROUGH FRIDAY...BEING REINFORCED BY AN ADDITIONAL AREA OF HIGH PRESSURE SETTLING ACROSS NRN ONTARIO THURSDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...KC MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
508 AM EDT MON SEP 21 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 507 AM EDT MON SEP 21 2015 WV IMAGERY AND RAP ANALYSIS INDICATED ZONAL MID/UPPER LEVEL FLOW FROM THE PAC NW INTO NRN ONTARIO AND A WEAK TROUGH OVER THE GREAT LAKES. A VIGOROUS SHRTWV TROUGH WAS MOVING THROUGH SRN ALBERTA. AT THE SFC...INCREASING SRLY FLOW PREVAILED ACROSS THE UPPER MS VALLEY INTO THE WRN LAKES BETWEEN HIGH PRES OVER NEW ENGLAND AND A TROUGH EXTENDING INTO THE PLAINS FROM LOW PRES OVER SRN SASK/MANITOBA. THE WAA PATTERN SUPPORTED ONLY PATCHY MID CLOUDS FROM WRN LAKE SUPERIOR THROUGH WI. TODAY...ABUNDANT SUNSHINE AND MIXING THROUGH 850 MB TEMPS CLIMBING INTO THE 10C-12C RANGE WILL SUPPORT MAX TEMPS IN THE LOW TO MID 70S. SLIGHTLY WARMER CONDITIONS WILL AGAIN PREVAIL IN DOWNSLOPE FLOW LOCATIONS ALONG LAKE SUPERIOR. FCST WINDS THROUGH THE MIDDLE AND UPPER PORTION OF THE MIXED LAYER SUPPORT WIND GUSTS INTO THE 20-25 MPH RANGE WITH SOME 25-30 MPH GUSTS OVER THE WEST. TONIGHT...AS THE VIGOROUS SHRTWV TROUGH AND ASSOCIATED DEEP SFC LOW LIFTS FROM NRN MANITOBA TO HUDSON BAY A COLD FRONT WILL BE DRAGGED THROUGH THE NRN LAKES. GIVEN THE ABSENCE OF DEEP MOISTURE...ONLY MODEST MOISTURE TRANSPORT ALONG THE FRONT AS WELL AS THE STRONGEST MID LEVEL FORCING REMAINING WELL TO THE N OVER NRN ONTARIO (SLIGHT HEIGHT RISES ARE FCST OVER THE NRN LAKES TONIGHT)...WILL CONTINUE TO MENTION ONLY LOWER END CHANCE POPS FOR SHRA/TSRA OVER NORTHWEST HALF LATE TONIGHT. MUCAPE VALUES INTO THE 500-1000 J/KG RANGE WILL SUPPORT TSRA CHANCES BUT WILL BE MARGINAL FOR THE POTENTIAL OF ANY STRONGER STORMS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 346 AM EDT MON SEP 21 2015 LIMITED CHANGES IN THE OVERALL LONG TERM FORECAST FROM 24 HOURS AGO...AS THE UPPER JET TRACKS FROM WEST TO EAST ACROSS SOUTHERN CANADA THROUGH THE LATER PART OF THIS WEEK BEFORE AMPLIFYING OVER CENTRAL CANADA FOR NEXT WEEKEND. THAT LOCATION OF THE JET WILL KEEP THE NORMAL (MIDDLE OF THIS WEEK) TO ABOVE NORMAL TEMPERATURES (THIS WEEKEND) IN PLACE THROUGHOUT THE FORECAST PERIOD. THERE ARE TWO OPPORTUNITIES FOR RAIN DURING THIS FORECAST PERIOD...WITH THE FIRST TIED TO THE COLD FRONT DROPPING SOUTHEAST ACROSS THE AREA ON TUESDAY MORNING. THE COMBINATION OF LIMITED MOISTURE AND UPPER LEVEL SUPPORT SHOULD ONLY LEAD TO ISOLATED SHOWERS DROPPING SOUTHEAST ACROSS THE CENTRAL/EASTERN U.P. AS THE FRONT MOVES THROUGH THAT AREA ON TUESDAY. DID CONTINUE TO MENTION A SLIGHT CHANCE OF THUNDER DUE TO THE THIN REGION OF WEAK INSTABILITY AHEAD OF THE FRONT. CANADIAN HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND THE FRONT AND SHOULD LEAD TO MOSTLY CLEAR SKIES OVER THE WESTERN U.P. TUESDAY AFTERNOON AND THE REST OF THE AREA ON TUESDAY NIGHT. THE NEXT OPPORTUNITY FOR RAIN WILL COME FROM BROAD WARM AIR ADVECTION DEVELOPING ON TUESDAY NIGHT IN THE MID-UPPER MISSISSIPPI VALLEY THAT WILL LIFT NORTH-NORTHEAST INTO THE WESTERN CWA ON WEDNESDAY. THERE SHOULD BE PLENTY OF MOISTURE TO WORK WITH THIS AS EXISTING MOISTURE IN THE PLAINS COMBINES WITH THE REMNANTS OF TROPICAL DEPRESSION SIXTEEN-E CURRENTLY NEAR THE BAJA PENINSULA. THE LATEST TRENDS IN THE MODELS KEEPS MUCH OF THE ENERGY FROM THE TROPICAL REMNANTS IN THE CENTRAL PLAINS...SO THE PRECIPITATION WILL BE TIED TO THAT INITIAL SURGE OF WARM AIR ADVECTION ON WEDNESDAY INTO WEDNESDAY NIGHT. THAT SURGE WILL BE OVER NORTHEAST MINNESOTA INTO NORTHWEST WISCONSIN ON WEDNESDAY MORNING AND THEN SLIDE EAST INTO WESTERN LAKE SUPERIOR AND THE WESTERN U.P. THROUGH THE DAY ON WEDNESDAY. WILL FOCUS THE HIGHEST POPS IN THAT AREA AND THEN SLOWLY DIMINISH THEM AS THE FORCING WEAKENS AND MOVES EAST ACROSS THE REST OF THE CWA WEDNESDAY NIGHT INTO THURSDAY. MODELS SHOWING PWAT VALUES RISING TOWARDS 1.5 INCHES...WHICH IS WELL ABOVE NORMAL AND LEADS TO THE POTENTIAL FOR LOCALLY HEAVY RAIN OVER WESTERN LAKE SUPERIOR AND THE WESTERN U.P WITH ANY EMBEDDED THUNDERSTORMS. A 1036MB HIGH MOVING INTO NORTHERN ONTARIO ON THURSDAY WILL EXTEND A RIDGE SOUTH TOWARDS LAKE SUPERIOR THURSDAY INTO THURSDAY NIGHT. THAT WILL SHIFT THE LOW LEVEL FLOW TO THE NORTHEAST AND START TO BRING DRIER AIR INTO THE AREA. EXPECT THE DIMINISHING UPPER LEVEL SUPPORT AND GREATER INFLUENCE OF THE HIGH TO CONTINUE INTO THURSDAY NIGHT AS THE HIGH MOVES OVER JAMES BAY. THAT SHOULD REALLY DIMINISH PRECIPITATION CHANCES HEADING INTO FRIDAY...ALTHOUGH THERE COULD BE ENOUGH LINGERING LOW LEVEL MOISTURE TO SUPPORT SOME SHOWERS OVER THE WESTERN U.P. ON THE EDGE OF THE RIDGE. AT THIS POINT...THE WEEKEND LOOKS DRY WITH THE UPPER RIDGE BUILDING OVER CENTRAL CANADA AND THE SURFACE HIGH DROPPING SOUTHEAST INTO THE NEW ENGLAND STATES. THIS WILL KEEP THE UPPER GREAT LAKES REGION UNDER THE WESTERN EDGE OF THE SURFACE RIDGE AND WITH MIXING TO 875MB TEMPS AROUND 10C ON SATURDAY WOULD SUPPORT HIGHS IN THE LOW 70S AND THEN SLIGHTLY HIGHER TEMPS ON SUNDAY WITH A LITTLE BETTER MIXING. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 143 AM EDT MON SEP 21 2015 A DRY SSW FLOW ARND HI PRES MOVING INTO THE NE STATES WL BRING VFR CONDITIONS TO ALL 3 TAF SITES THRU THE FORECAST PERIOD. AS THE PRES GRADIENT TIGHTENS EARLY THIS MRNG DURING NOCTURNAL COOLING...EXPECT SOME LLWS TO IMPACT IWD...WHERE THE PRES GRADIENT WL BE SHARPER AND THE LLJ STRONGER AT THE BASE OF THE RADIATION INVRN. AT CMX AND SAW...THE LLWS POTENTIAL SEEMS MORE MARGINAL...SO LEFT OUT OF THE FCST FOR NOW. THE ONSET OF DAYTIME HEATING/MIXING WILL RESULT IN SOME GUSTY SW WINDS BY MID/LATE MRNG. SINCE THE PRES GRADIENT WL SHARPEN EVEN MORE THIS EVNG AS A COLD FNT APRCHS FM THE W...EXPECT GUSTY WINDS TO PERSIST EVEN AFTER SUNSET. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 157 PM EDT SUN SEP 20 2015 HIGH PRESSURE OVER THE LOWER GREAT LAKES WILL SLOWLY EXIT ACROSS THE NEW ENGLAND STATES MONDAY AND TUESDAY. THIS WILL BE WHILE A LOW OVER MANITOBA MONDAY MORNING SHIFTS AND DEEPENS ACROSS HUDSON BAY MONDAY NIGHT THROUGH TUESDAY. THE RESULT WILL BE AN INCREASING PRESSURE GRADIENT...WITH WINDS MONDAY-MONDAY NIGHT OF 20-25KTS. EXPECT THE LOW TO DRAG A TROUGH ACROSS LAKE SUPERIOR MONDAY AFTERNOON THROUGH EARLY TUESDAY. BEHIND THE LOW...HIGH PRESSURE ACROSS NORTH DAKOTA TUESDAY MORNING WILL DRIFT OVER LAKE SUPERIOR TUESDAY AFTERNOON...BEFORE EXPANDING NORTH ACROSS ONTARIO WEDNESDAY. A RIDGE WILL REMAIN THROUGH FRIDAY...BEING REINFORCED BY AN ADDITIONAL AREA OF HIGH PRESSURE SETTLING ACROSS ONTARIO THURSDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...KC MARINE...KF
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
330 AM CDT MON SEP 21 2015 .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 330 AM CDT MON SEP 21 2015 THE PRIMARY FORECAST CONCERNS IN THIS PERIOD ARE PCPN CHANCES... ESPECIALLY FOR WED...AND TEMPERATURES THE NEXT FEW DAYS. SECONDARY CONCERN TODAY IS COVERAGE OF LOW CLOUDS TODAY. MAIN FEATURES FROM UPPER LEVEL CHARTS LAST EVENING WERE A 115 KT JET MAX AT 300 MB PUSHING EWD INTO SRN BC AND A MID LEVEL SHORTWAVE TROUGH ASSOCIATED WITH THAT JET MAX. 12 HOUR HEIGHT FALLS OF UP TO 80 METERS WERE NOTED IN BC AT CWXS AT 500 MB. LATEST WATER VAPOR LOOP IN COMBINATION WITH MOST RECENT RUC MODEL INITIALIZATION SHOWED THESE HAD MOVED INTO SRN ALTA AS OF 08Z. THE OTHER FEATURE OF CONCERN IN STLT IMAGERY WAS THE MOISTURE FROM TD16 MOVING NWD TOWARD SRN AZ. TODAY...LOW CLOUDS WILL BE PROBLEMATIC. THESE WERE CURRENTLY DOWN ACROSS KS AND SOME OF THE SHORT RANGE MODELS MOVE/DEVELOP THESE UP INTO OUR AREA. HOW LONG THEY STAY AROUND WILL HAVE AN IMPACT ON HIGHS TODAY...AND FOR NOW FELT MOST SPOTS WOULD STAY IN THE UPPER 70S...WITH SOME LOWER 80S NORTH. WE WILL HAVE SOME MIXING WITH THE SLY FLOW...BUT THAT MAY ONLY BE TO ABOUT 875 MB. LOW CLOUDS MAY MOVE BACK IN TONIGHT. WE HAVE HAD BEEN CARRYING A SLIGHT CHANCE OF TSTMS...BUT LOOKING AT THINGS CLOSER THE ELEVATED INSTABILITY MAY NOT BE REALIZED. IT MAY END UP BEING DRIZZLE IF ANYTHING. FOR NOW...BACKED OFF TO JUST A SLIGHT CHANCE OF SHOWERS. LOWS SHOULD BE HELD UP WITH SLY FLOW AND AN INCREASE IN LOW LEVEL MOISTURE. MOS GUIDANCE SEEMS REASONABLE WITH LOWER AND MID 60S. THE 00Z NAM SHOWED SOME TSTMS DEVELOPING TUE MORNING OVER PARTS OF ERN NE...AND THAT SCENARIO SEEMS PLAUSIBLE WITH DECENT MID LEVEL LAPSE RATES AND ELEVATED INSTABILITY. TEMPERATURES SHOULD WARM INTO THE 80S IN THE AFTN. KEPT A SLIGHT CHANCE OF TSTMS FOR TUE NIGHT INTO WED MORNING... AS PW VALUES INCREASE TO OVER 1.50 INCHES...BUT BETTER FOCUS MAY BE MORE IN ERN SD/NWRN IA/SWRN MN. THREAT FOR STRONG STORMS AND LOCALLY HEAVY RAIN WILL BE INCREASING IN OUR WRN COUNTIES BY LATE WED AFTN. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 330 AM CDT MON SEP 21 2015 HEAVY RAIN THREAT WITH STRONG STORMS MAY LINGER INTO AT LEAST WED EVENING...WITH CHANCES HIGHEST WEST OF A LINE FROM BEATRICE AND LINCOLN TOWARD WAYNE. DETAILS ON THIS SHOULD BECOME MORE CLEAR BY TOMORROW. SYSTEM THEN SOMEWHAT STALLS OUT OVER THE CNTRL PLAINS THU BEFORE SLOWLY WEAKENING. HAVE SOME POPS MENTIONED UNTIL FRI... THEN IT LOOKS MAINLY DRY. TEMPERATURES SHOULD BE AT OR ABOVE NORMAL THE WHOLE WEEK. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1150 PM CDT SUN SEP 20 2015 MAY SEE A FEW HOURS OF VISIBILITY IN THE MVFR RANGE TOWARD DAWN AS MOISTURE RETURNS TO THE AREA...BUT WINDS IN THE 7-10KT RANGE WILL HINDER LOWER VISIBILITIES. OTHERWISE...VFR CONDITIONS AND MOSTLY CLEAR SKIES ARE EXPECTED THROUGH THE TAF CYCLE. SOUTH TO SOUTHEAST WINDS WILL PERSIST THROUGH MONDAY...WITH SOME GUSTS DURING THE AFTERNOON THAT DECREASE DIURNALLY AROUND SUNSET. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...MILLER LONG TERM...MILLER AVIATION...MAYES
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
459 AM EDT MON SEP 21 2015 .SYNOPSIS... A WEAK UPPER DISTURBANCE COULD BRING SOME UNSETTLED CONDITIONS TO SOUTHERN AREAS TODAY AND TUESDAY...OTHERWISE THE WEEK WILL BE DOMINATED BY HIGH PRESSURE AND MODERATING TEMPERATURES. && .NEAR TERM /THROUGH TONIGHT/... THE NEAR TERM WILL BE DOMINATED BY AN AMPLIFYING UPPER TROUGH MOVING INTO THE OHIO VALLEY...AND LOW LEVEL FLOW THAT WILL TAKE ON A TRAJECTORY OFF THE MID ATLANTIC COAST. MODELS HAVE BEEN CONSISTENT IN WANTING TO BRING CLOUDS AND THE CHANCE FOR SOME LIGHT RAIN OR POSSIBLY EVEN DRIZZLE OVER SOUTHERN SECTIONS...PERHAPS AS FAR NORTH AS THE CENTRAL MOUNTAINS AND MID SUSQ VALLEY...TODAY AND EARLY TUESDAY UNDER THE WEAK BUT PERSISTENT LOW LEVEL ISENTROPIC LIFT. SO FAR THERE IS NOT MUCH GOING ON UPSTREAM TO GET EXCITED ABOUT...WITH LOW CLOUDS JUST HAVING BEGUN TO ENCROACH ON THE NJ COAST. THE DIFFERENT FLAVORS OF THE WRF SHOW THE LIGHT PRECIP DEVELOPING FROM SOUTH TO NORTH MAINLY AFTER MID DAY OR EVEN MID AFTERNOON...WHILE THE HRRR CONSISTENTLY WANTS TO BRING LIGHT PRECIP NORTH BEFORE THE MORNING IS OUT. THIS IDEA OF LIGHT QPF IS BACKED UP BY THE SREF AND GEFS AS WELL. REGARDLESS OF THE SENSIBLE WEATHER CONCERNS FOR TODAY...IT WILL BE A COOLER DAY THAN SUNDAY OVER MOST OF THE AREA. TEMPS WILL AVERAGE IN THE MID TO UPPER 60S REGION WIDE. COOLER THAN SUNDAY OVER THE CLOUDIER SOUTH...BUT A BIT WARMER THAN SUNDAY OVER THE SUNNIER NORTH. IT SHOULD REMAIN FAIR OVER THE NORTH TONIGHT...WHILE CLOUDY AND DAMP CONDITIONS DOMINATE THE CENTRAL AND SOUTHERN AREAS. THE CHANCE FOR SOME LIGHT RAIN OR DRIZZLE WILL CONTINUE...BUT OVERALL PRECIP AMOUNTS WILL REMAIN ON THE MEAGER SIDE. && .SHORT TERM /TUESDAY/... THE BEST CHANCE FOR RAIN WILL BE THE FIRST HALF OF TUESDAY AND OVER SOUTHERN AREAS AS THE LAST VESTIGES OF THE WEAK LOW LEVEL UPSLOPE FLOW FINALLY BEGINS TO RELAX...AND THE MASSIVE RIDGE FROM OLD MEXICO UP INTO THE CENTRAL US BEGINS TO POKE ITS NOSE INTO THE LOCAL AREA. LOOKS FOR BRIGHTENING SKIES...SLOWER TO IMPROVE OVER THE SOUTH...WITH HIGHS MAKING BACK INTO THE UPPER 60S AND LOWER 70S IN MOST AREAS. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... THE EXTENDED FORECAST LOOKS LIKE WE WILL BE THE BENEFICIARIES OF THE GOOD PART OF A DEVELOPING REX BLOCK. MED RANGE GUIDANCE IS IN GOOD AGREEMENT WITH A HUGE AREA OF ABOVE NORMAL UPPER HEIGHTS EXTENDING FROM MEXICO UP TO SOUTHERN CANADA AND EAST THROUGH THE NORTHEASTERN US. THE TROUGH THAT WILL GIVE US A BIT OF INCLEMENT WEATHER EARLY...IS MADE TO CLOSE OFF UNDER THE RIDGE LEADING TO A NEARLY CLASSIC LOOKING REX BLOCK UPPER PATTERN BY MID TO LATE WEEK. BY WEDNESDAY...THE FIRST DAY OF FALL...AND LASTING INTO NEXT WEEKEND...I HAVE FAIR SKIES AND DAYTIME HIGHS GENERALLY IN THE 70S WITH LOW HUMIDITY. HIGHS WILL BE AVERAGING SOME 4-8 DEG ABOVE NORMAL. ASTRONOMICAL FALL STARTS AT 4:21 AM EDT ON SEPTEMBER 23. && .AVIATION /09Z MONDAY THROUGH FRIDAY/... ONLY MINOR CHANGES NEEDED FOR 09Z TAF PACKAGE. EARLIER DISCUSSION BELOW. MAIN CHANGE TO 06Z TAFS WAS TO ADD A GROUP TO JST. SOME HIGH CLOUDS ACROSS SOUTHERN PA AS OF 1 AM. HIGH PRESSURE NORTH OF PA WILL ENSURE FAIR WEATHER AND LIGHT WINDS OVERNIGHT. WHERE THE PRES GRADIENT IS WEAKEST ACROSS NORTHERN PA...THERE COULD BE SOME PATCHY VALLEY FOG ARND DAWN MONDAY...POTENTIALLY AFFECTING KBFD. AN INCREASINGLY MOIST EASTERLY FLOW WILL FORM OVER SOUTHERN PA ON MONDAY IN RESPONSE TO A TIGHTENING PRES GRADIENT BTWN HIGH PRES OVR NEW ENGLAND AND LOW PRES OFF THE SE COAST. THE INFLUX OF ATLANTIC MOISTURE...COMBINED WITH APPROACH OF AN UPPER LVL DISTURBANCE FROM THE OHIO VALLEY...WILL LIKELY PRODUCE LOWERING CIGS AND SOME OCNL LIGHT RAIN ACROSS SOUTHERN PA BY MON AFTN. BLEND OF 15Z SREF AND 18Z OPER MDLS SUGGEST MVFR RESTRICTIONS ARE LIKELY AT KJST/KAOO BY LATE IN THE DAY AND POSSIBLE AT KMDT/KLNS. BY MON NIGHT...MDL SOUNDINGS IMPLY IFR CIGS ARE POSSIBLE AT KJST/KAOO. OUTLOOK... TUE...NO SIG WX EXPECTED. WED-THU...AM FOG POSSIBLE KBFD/KIPT. FRI...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LA CORTE AVIATION...FITZGERALD/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
440 AM EDT MON SEP 21 2015 .SYNOPSIS... A WEAK UPPER DISTURBANCE COULD BRING SOME UNSETTLED CONDITIONS TO SOUTHERN AREAS TODAY AND TUESDAY...OTHERWISE THE WEEK WILL BE DOMINATED BY HIGH PRESSURE AND MODERATING TEMPERATURES. && .NEAR TERM /THROUGH TONIGHT/... THE NEAR TERM WILL BE DOMINATED BY AN AMPLIFYING UPPER TROUGH MOVING INTO THE OHIO VALLEY...AND LOW LEVEL FLOW THAT WILL TAKE ON A TRAJECTORY OFF THE MID ATLANTIC COAST. MODELS HAVE BEEN CONSISTENT IN WANTING TO BRING CLOUDS AND THE CHANCE FOR SOME LIGHT RAIN OR POSSIBLY EVEN DRIZZLE OVER SOUTHERN SECTIONS...PERHAPS AS FAR NORTH AS THE CENTRAL MOUNTAINS AND MID SUSQ VALLEY...TODAY AND EARLY TUESDAY UNDER THE WEAK BUT PERSISTENT LOW LEVEL ISENTROPIC LIFT. SO FAR THERE IS NOT MUCH GOING ON UPSTREAM TO GET EXCITED ABOUT...WITH LOW CLOUDS JUST HAVING BEGUN TO ENCROACH ON THE NJ COAST. THE DIFFERENT FLAVORS OF THE WRF SHOW THE LIGHT PRECIP DEVELOPING FROM SOUTH TO NORTH MAINLY AFTER MID DAY OR EVEN MID AFTERNOON...WHILE THE HRRR CONSISTENTLY WANTS TO BRING LIGHT PRECIP NORTH BEFORE THE MORNING IS OUT. THIS IDEA OF LIGHT QPF IS BACKED UP BY THE SREF AND GEFS AS WELL. REGARDLESS OF THE SENSIBLE WEATHER CONCERNS FOR TODAY...IT WILL BE A COOLER DAY THAN SUNDAY OVER MOST OF THE AREA. TEMPS WILL AVERAGE IN THE MID TO UPPER 60S REGION WIDE. COOLER THAN SUNDAY OVER THE CLOUDIER SOUTH...BUT A BIT WARMER THAN SUNDAY OVER THE SUNNIER NORTH. IT SHOULD REMAIN FAIR OVER THE NORTH TONIGHT...WHILE CLOUDY AND DAMP CONDITIONS DOMINATE THE CENTRAL AND SOUTHERN AREAS. THE CHANCE FOR SOME LIGHT RAIN OR DRIZZLE WILL CONTINUE...BUT OVERALL PRECIP AMOUNTS WILL REMAIN ON THE MEAGER SIDE. && .SHORT TERM /TUESDAY/... THE BEST CHANCE FOR RAIN WILL BE THE FIRST HALF OF TUESDAY AND OVER SOUTHERN AREAS AS THE LAST VESTIGES OF THE WEAK LOW LEVEL UPSLOPE FLOW FINALLY BEGINS TO RELAX...AND THE MASSIVE RIDGE FROM OLD MEXICO UP INTO THE CENTRAL US BEGINS TO POKE ITS NOSE INTO THE LOCAL AREA. LOOKS FOR BRIGHTENING SKIES...SLOWER TO IMPROVE OVER THE SOUTH...WITH HIGHS MAKING BACK INTO THE UPPER 60S AND LOWER 70S IN MOST AREAS. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... THE EXTENDED FORECAST LOOKS LIKE WE WILL BE THE BENEFICIARIES OF THE GOOD PART OF A DEVELOPING REX BLOCK. MED RANGE GUIDANCE IS IN GOOD AGREEMENT WITH A HUGE AREA OF ABOVE NORMAL UPPER HEIGHTS EXTENDING FROM MEXICO UP TO SOUTHERN CANADA AND EAST THROUGH THE NORTHEASTERN US. THE TROUGH THAT WILL GIVE US A BIT OF INCLEMENT WEATHER EARLY...IS MADE TO CLOSE OFF UNDER THE RIDGE LEADING TO A NEARLY CLASSIC LOOKING REX BLOCK UPPER PATTERN BY MID TO LATE WEEK. BY WEDNESDAY...THE FIRST DAY OF FALL...AND LASTING INTO NEXT WEEKEND...I HAVE FAIR SKIES AND DAYTIME HIGHS GENERALLY IN THE 70S WITH LOW HUMIDITY. HIGHS WILL BE AVERAGING SOME 4-8 DEG ABOVE NORMAL. ASTRONOMICAL FALL STARTS AT 4:21 AM EDT ON SEPTEMBER 23. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... MAIN CHANGE TO 06Z TAFS WAS TO ADD A GROUP TO JST. SOME HIGH CLOUDS ACROSS SOUTHERN PA AS OF 1 AM. EARLIER DISCUSSION BELOW. HIGH PRESSURE NORTH OF PA WILL ENSURE FAIR WEATHER AND LIGHT WINDS OVERNIGHT. WHERE THE PRES GRADIENT IS WEAKEST ACROSS NORTHERN PA...THERE COULD BE SOME PATCHY VALLEY FOG ARND DAWN MONDAY...POTENTIALLY AFFECTING KBFD. AN INCREASINGLY MOIST EASTERLY FLOW WILL FORM OVER SOUTHERN PA ON MONDAY IN RESPONSE TO A TIGHTENING PRES GRADIENT BTWN HIGH PRES OVR NEW ENGLAND AND LOW PRES OFF THE SE COAST. THE INFLUX OF ATLANTIC MOISTURE...COMBINED WITH APPROACH OF AN UPPER LVL DISTURBANCE FROM THE OHIO VALLEY...WILL LIKELY PRODUCE LOWERING CIGS AND SOME OCNL LIGHT RAIN ACROSS SOUTHERN PA BY MON AFTN. BLEND OF 15Z SREF AND 18Z OPER MDLS SUGGEST MVFR RESTRICTIONS ARE LIKELY AT KJST/KAOO BY LATE IN THE DAY AND POSSIBLE AT KMDT/KLNS. BY MON NIGHT...MDL SOUNDINGS IMPLY IFR CIGS ARE POSSIBLE AT KJST/KAOO. OUTLOOK... TUE...NO SIG WX EXPECTED. WED-THU...AM FOG POSSIBLE KBFD/KIPT. FRI...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LA CORTE AVIATION...FITZGERALD/MARTIN
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
443 AM CDT MON SEP 21 2015 .UPDATE... WITH WEAK UPPER LEVEL DISTURBANCE MOVING ACROSS SRN PORTIONS OF MID STATE AS OF 09Z(4AM CDT)...AND HRRR MODEL SHOWING THIS POSSIBILITY CONTINUING THRU 16Z(11 AM CDT)...WILL UPDATE THE SUITE OF FORECAST PRODUCTS TO MENTION A SLIGHT CHANCE TO CHANCE OF SHWRS ACROSS THESE AREAS THRU 16Z. SOME OF THE ABOVE MENTIONED RAINFALL MAY NOT BE ACTUALLY REACHING THE GROUND PER DRY AIR NOTED ACROSS THIS AREA GENERALLY BELOW 700MB PER MOST RECENT LAPS SOUNDING PROFILES. && .PREV DISCUSSION.../ISSUED 246 AM CDT MON SEP 21 2015/ SHORT TERM(TODAY-WED NIGHT)... FORECAST QUANDARIES...SKY COVER TIMING EROSION TODAY...TEMPS. A STRAIGHT FORWARD FORECASTS THRU WED NIGHT...WITH STRONG CONSENSUS BETWEEN MODEL SOLUTION RESOLUTIONS. HIGH PRESSURE INFLUENCES AND UPPER LEVEL RIDGING INFLUENCES BUILDING IN FROM THE MS RIVER VALLEY WILL BE THE MAIN WX PLAYERS ACROSS THE MID STATE THRU WED NIGHT. CLOUD COVERAGE APPROACHING 08Z WILL CONTINUE TO PUSH EWD AND OUT OF THE AREA AS THE DAY PROGRESSES...AS UPPER LEVEL TROUGHING INFLUENCES MOVE EWD AND ABOVE MENTIONED UPPER LEVEL RIDGING INFLUENCES BUILD ACROSS THE AREA. WILL THUS TAILOR CLOUD CONDITIONS TODAY FOR A DECREASING CLOUDINESS TREND W MID MORNING THRU EARLY AFTERNOON E. MOCLR SKIES ARE EXPECTED TONIGHT THRU WED NIGHT. SFC HIGH PRESSURE INFLUENCES WILL BUILD INTO THE MID STATE FROM THE SRN OHIO RIVER VALLEY TODAY BEFORE MERGING WITH HIGH PRESSURE INFLUENCES ACROSS THE NE U.S. AS FOR TEMPS...HIGH TEMPS TODAY WILL BE AROUND SEASONAL NORMAL VALUES... AROUND 80 TO LOWER 80S...MID TO UPPER 70S PLATEAU. TEMPS WILL WARM UP TO A FEW DEGREES ABOVE SEASONAL NORMAL VALUES...LOW TO MID 80S...UPPER 70S PLATEAU...BY WED AFTERNOON. LOWS WILL BE A FEW DEGREES BELOW SEASONAL NORMAL VALUES TONIGHT...MAINLY IN THE LOW TO MID 50S. LOWS ARE EXPECTED TO RISE MAINLY INTO THE UPPER 50S ACROSS THE AREA BY WED NIGHT. LONG TERM(THU-SUN)... THE GFS PROGRESSION OF THE EXT WEATHER PATTERN SEEMS TO BE A BIT MORE BELIEVABLE AS OPPOSED TO THE EURO SOLUTION. THE ORIENTATION OF THE UPPER RIDGE AXIS LOOKS A BIT UNORTHODOX AS IT STRETCHES FROM THE DESERT SOUTHWEST NORTHEASTWARD AND THE SOUTHEAST ACROSS THE MID ATLANTIC. MEANWHILE...THE GFS SOLUTIONS SHOWS A GENTLE RETROGRADE MOTION IN REGARD TO WEAK UPPER LEVEL TROUGHING OVER THE SOUTHEASTERN U.S. THEREFORE...IN THIS EXT FCST...WILL LEAN TOWARD THE GFS SOLUTION. ON THURSDAY...THE WEAK UPPER TROUGH WILL RESIDE ACROSS GA AND EASTERN TN. THIS WILL CONTINUE TO KEEP MIDDLE TN ON THE DRY SIDE IN THE MID AND UPPER LEVELS. IN THE LOWER LEVELS...A LARGE SFC HIGH OVER SOUTHERN PORTIONS OF THE HUDSON BAY WILL PROVIDE MAINLY AN EASTWARD COMPONENT IN THE LOWER LEVELS. THUS...THE OVERALL PATTERN WILL BE ON THE DRY SIDE. AS WE MOVE TOWARD THE WEEKEND...THE AFOREMENTIONED SFC HIGH WILL MOVE SOUTHEASTWARD AND REACH THE NEW ENGLAND AREA BY SUNDAY. AS A SOUTHWESTERN SFC RIDGE DEVELOPS TOWARD THE CAROLINAS...MORE OF A SOUTHERLY LOW LEVEL WIND COMPONENT WILL SET UP IN OUR NECK OF THE WOODS. IN THE UPPER LEVELS...THE UPPER LEVEL TROUGH WILL NOW BE LOCATED WEST OF THE MID STATE. THIS WILL PROVIDE A REBOUND OF MOISTURE IN THE MID AND UPPER LEVELS. SO FOR THE FCST...WILL BEGIN TO BRING BACK LOW CHANCES OF SHOWER ACTIVITY...MAINLY ACROSS EASTERN AREAS. THE EURO IS DRY THROUGHOUT THE PERIOD...SO EVEN THOUGH THATS NOT THE MODEL OF CHOICE...A BLEND AND A TREND TOWARD ISC GRIDS WILL KEEP POPS ON THE LOW SIDE FOR NOW. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 81 55 83 58 / 10 10 0 0 CLARKSVILLE 80 51 82 53 / 10 0 0 0 CROSSVILLE 74 52 77 55 / 10 10 0 0 COLUMBIA 81 51 83 54 / 40 10 0 0 LAWRENCEBURG 80 54 82 56 / 40 10 0 0 WAVERLY 81 53 83 54 / 10 0 0 0 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 31
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
417 AM CDT MON SEP 21 2015 .SHORT TERM (TODAY THROUGH TUESDAY)... AREA RADAR DATA SHOWS AN OUTFLOW BOUNDARY CURRENTLY LOCATED ALONG A BURNET TO ROUND ROCK TO GIDDINGS LINE. THIS FEATURE IS WEAK AS SURFACE OBSERVATIONS DO NOT SHOW ANY WIND SHIFT NORTH OF THE MENTIONED AREAS. SURFACE OBSERVATIONS DO SHOW LIGHT WINDS AND PLENTY OF MOISTURE EAST OF I-35. CAN/T RULE OUT SOME PATCHY FOG THIS MORNING EAST OF I-35 AND WE/LL CONTINUE TO MENTION IN THE LATEST FORECAST. OTHERWISE...INFRARED SATELLITE CONTINUES TO SHOW PLENTY OF MID AND HIGH LEVEL CLOUD COVER ACROSS THE REGION. THIS CLOUD COVER WILL GRADUALLY THIN FROM NORTH TO SOUTH TODAY AS SOME WEAK UPPER LEVEL SHORT WAVE TROUGHS MOVE THROUGH EAST TEXAS. A DRY AND WARM FORECAST IS IN STORE TODAY AND TOMORROW AS MID- LEVEL RIDGING REMAINS THE DOMINANT WEATHER FEATURE. WE/LL ONCE AGAIN SEE HIGHS IN THE 90S AND LOWS IN THE MID 60S AND 70S. && .LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)... THE SUBTROPICAL RIDGE AXIS CONTINUES THROUGH WEDNESDAY FOR MORE ABOVE NORMAL TEMPERATURES AND DRY WEATHER ACROSS SOUTH CENTRAL TEXAS. THE RIDGE BEGINS TO BREAK DOWN ON THURSDAY AS AN UPPER LOW MOVES INTO THE CENTRAL PLAINS STATES. THE FORECAST THROUGH THE REMAINDER OF THE PERIOD WILL BE LARGELY DETERMINED ON THE DEVELOPMENT OF AN UPPER LEVEL LOW PRESSURE SYSTEM OVER THE SOUTHERN U.S. PLAINS. THE OPERATIONAL ECMWF AND GFS NOW DIFFER CONSIDERABLY WITH THIS FEATURE AS COMPARED TO PREVIOUS MODEL DATA. FOR NOW...WE/LL GO WITH CONTINUED DRY WEATHER ALONG WITH A VERY GRADUAL COOL DOWN. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 94 73 96 72 95 / - - - - 0 AUSTIN BERGSTROM INTL AIRPORT 94 68 95 68 94 / - - - - 0 NEW BRAUNFELS MUNI AIRPORT 95 70 96 69 97 / 0 - - 0 0 BURNET MUNI AIRPORT 93 71 94 70 93 / 0 - - - 0 DEL RIO INTL AIRPORT 95 72 95 72 95 / 0 - - 0 0 GEORGETOWN MUNI AIRPORT 94 70 94 71 94 / - - - - 0 HONDO MUNI AIRPORT 94 68 96 69 95 / 0 - - 0 0 SAN MARCOS MUNI AIRPORT 93 70 94 69 94 / - - - 0 0 LA GRANGE - FAYETTE REGIONAL 93 71 95 69 94 / 10 - - 0 0 SAN ANTONIO INTL AIRPORT 93 73 95 72 94 / 0 - - 0 0 STINSON MUNI AIRPORT 95 72 95 71 95 / 0 - - 0 0 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...LH SYNOPTIC/GRIDS...24
  [top] Area Forecast Discussion National Weather Service Midland/Odessa TX 408 AM CDT MON SEP 21 2015 .DISCUSSION...As of 4:00 AM CDT Monday...The main weather maker for the next couple of days will be EPAC TD 16-E which is moving across south central Baja California Sur. Southwesterly shear is displacing the thunderstorm activity into Sonora Mexico. Ridging is centered over West Texas/SE New Mexico. As the remnants of TD 16-E move into the Desert SW mid level moisture and instability will increase across the Davis and Guadalupe Mtns. Both the high resolution HRRR and RAP13 models and the mesoscale models indc convection possible over the Mtns thru mid week. The mid/upper level feature associated with this system will move NE through Northern New Mexico tonight/Tuesday with the ridge flattening. Have slight chc pops as far east as the Western Permian Basin tonight/Tuesday. With the moist ground from recent rains have trended temps a little below MOS guidance. Medium range models start to diverge mid week. The GFS is weaker and further north with the remnant mid/upper level shortwave... placing it in the Northern Plains by Thursday with broad ridging centered over the Desert SW. The ECMWF keeps a stronger mid/upper level shortwave further south with the ridge further west. The ECMWF is significantly wetter and cooler for the CWA...especially the Permian Basin and Trans Pecos Thursday thru Saturday. Will keep thunderstorm chances in the Mtns Wed/Thu...and the CWA dry Friday thru next weekend under weak ridging. Strobin && .PRELIMINARY POINT TEMPS/POPS... BIG SPRING TX 89 67 89 64 / 0 0 10 10 CARLSBAD NM 84 68 83 65 / 10 40 40 30 DRYDEN TX 93 71 92 71 / 10 10 10 10 FORT STOCKTON TX 89 67 89 68 / 10 10 20 10 GUADALUPE PASS TX 77 61 77 59 / 20 50 30 40 HOBBS NM 84 64 80 63 / 0 20 20 10 MARFA TX 79 63 80 57 / 20 30 30 20 MIDLAND INTL AIRPORT TX 87 68 87 68 / 0 10 10 10 ODESSA TX 87 68 86 68 / 0 10 10 10 WINK TX 90 69 90 68 / 10 20 20 10 && .MAF WATCHES/WARNINGS/ADVISORIES... NM...NONE. TX...NONE. && $$ 72/33
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1152 PM CDT SUN SEP 20 2015 .AVIATION... VFR CONDITIONS IN PLACE AT KLBB BUT ALREADY SEEING BRIEF IFR CONDITIONS AT KCDS. WILL CONTINUE TO FORECAST MVFR TO IFR CEILINGS DEVELOPING IN THE EARLY MORNING HOURS MONDAY AND GRADUALLY BREAKING OUT BEFORE NOON LOCAL TIME AT ALL THREE TAF SITES. CONFIDENCE IS NOT ALL THAT HIGH ON HOW LOW CEILINGS WILL GET SO THERE COULD BE SOME ADJUSTMENTS THROUGH THE OVERNIGHT HOURS. AFTER CEILINGS BREAK OUT LATE TOMORROW MORNING...VFR CONDITIONS EXPECTED THROUGH THE REST OF THE DAY MONDAY. JORDAN && .PREV DISCUSSION... /ISSUED 637 PM CDT SUN SEP 20 2015/ AVIATION... A CLUSTER OF THUNDERSTORMS IS MOVING SOUTH TOWARDS THE KCDS AND TEMPO GROUP IN CURRENT TAF REFLECTS TIME OF ARRIVAL BASED ON CURRENT SPEED AND MOTION. OTHERWISE...VFR CONDITIONS WILL CONTINUE THROUGH EARLY TONIGHT. THERE IS AGAIN A POSSIBILITY OF MVFR CONDITIONS AT ALL THREE TAF SITES EARLY MONDAY MORNING BUT DO NOT EXPECT TO SEE IFR CONDITIONS. CEILINGS WILL GRADUALLY LIFT AFTER SUNRISE WITH VFR CONDITIONS RETURNING SHORTLY BEFORE NOON LOCAL TIME. JORDAN PREV DISCUSSION... /ISSUED 330 PM CDT SUN SEP 20 2015/ SHORT TERM... THE CENTER OF THE UA RIDGE REMAINS SOUTH OF THE SOUTH PLAINS AND ROLLING PLAINS LATE THIS AFTN...AND IS AIDING STREAMING A FETCH OF ERN PACIFIC MOISTURE FROM THE BAJA OF CALI TO ACROSS THE SOUTHERN PLAINS. HOWEVER...THE EMERGENCE OF A SLIGHT AMPLIFICATION OF UA RIDGING ACROSS THE SWRN CONUS IS HELPING TO VEER FLOW ALOFT FROM NEAR ZONAL TO THE NW AND AS SUCH...IS SLOWLY SHIFTING THE PLUME OF PACIFIC MOISTURE SWRD WITH TIME. LOOKING AT THE SFC...THANKS TO LAST NIGHTS ADEQUATE LLJ COUPLED WITH WAA...THE ONCE WIDELY SCATTERED SHOWERS FROM EARLIER THIS MORNING HAVE SINCE BECOME LINGERING SHOWERS MORE SO ACROSS THE LOW ROLLING PLAINS LATE THIS AFTN. THE UA RIDGE TO OUR WEST GRADUALLY EXPANDING WRD TOWARDS THE REGION IS HELPING TO FILTER IN DRIER AIR FROM THE TOP DOWN...INITIALLY NOTED ACROSS PORTIONS OF THE WRN...NWRN AND NRN ZONES GIVEN CLEARING SKIES THERE...AND WILL EVENTUALLY FILTER IN TO ACROSS THE SERN ZONES LATER THIS EVENING. SFC TROUGHING/A WARM FRONT DRAPED FROM NW TO SE ACROSS THE ERN TX PANHANDLE TO ACROSS THE NRN ROLLING PLAINS...COMBINED WITH A BIT OF INSOLATION....DETERIORATING CIN AND SB CAPE VALUES OF 1200+ J/KG ACROSS THE AFOREMENTIONED AREAS...RAISES CONCERN FOR A BRIEF PERIOD OF STORMS /POSSIBLY STRONG/ FIRING UP ALONG THE SFC TROUGH LATER THIS AFTN/EARLY THIS EVENING. IN FACT...RADAR TRENDS SHOWED CI OCCURRING ACROSS THE SE TX PANHANDLE NW OF WHEELER TX AS WELL AS SW OF MEMPHIS TX ALONG THAT SFC BOUNDARY. THE TTU WRF MAINTAINS THE CONVECTION NORTH OF THE CWA WHICH APPEARS TO NOT HANDLE THE CURRENT SITUATION. THE HRRR ON THE OTHER-HAND MAY HAVE A BETTER HANDLE ON THE PRECIP SITUATION...AS IT DEVELOPS SCATTERED STORMS ACROSS THE SRN AND SERN TX PANHANDLE WHICH THEN PUSHES SOUTH TO ACROSS THE NERN ZONES LATER THIS AFTN/EARLY EVENING...DESPITE THE MEAN FLOW BEING THE FROM THE W-SW. PERHAPS AN OUTFLOW BOUNDARY/A COLD POOL COULD AID IN THIS SWRD TRAJECTORY. HAVE THEREFORE ELECTED TO INSERT SLIGHT CHANCE POPS ACROSS THE NERN ZONES THIS EVENING THROUGH 21/06Z. TONIGHT...THE PLUME OF PACIFIC MOISTURE WILL HAVE SHIFTED SOUTH OF THE FA...AS THE UA RIDGE CONTINUES TO EXPAND WRD TOWARDS THE REGION. NWRLY FLOW WILL THEREFORE BRIEFLY BECOME ESTABLISHED...HOWEVER RAIN CHANCES LOOK FAIRLY LOW GIVEN THE FILTRATION OF DRIER AIR. IT IS INTERESTING TO NOTE THAT THE NAM SOLUTION IN PARTICULARLY HONES IN THE POTENTIAL OF FOG ESPECIALLY ON THE CAPROCK...AS SFC WINDS GO LIGHT AND VARIABLE AND CLEARING SKIES OCCUR. FURTHERMORE...IT IS LIKELY HANGING ITS HAT ON LAST NIGHT/S AND TODAY/S PRECIP ACTIVITY BEING ENOUGH TO KEEP THE GROUND RATHER SATURATED. THOUGH LOOKING BACK...THE BEST PRECIP /SEVERAL TENTHS OF AN INCH/ FELL ACROSS THE TX PANHANDLE AND PERMIAN BASIN VERSUS SPOTTY AMOUNTS OF A FEW HUNDREDTHS OF AN INCH UP TO PERHAPS A TENTH OF AN INCH ACROSS THE CWA. NOT SURE IF THAT WILL BE ENOUGH TO INITIATE RATHER DENSE FOG AS SHOWN VIA THE NAM /BELOW 1/4 MILE/ BUT PERHAPS LIGHT FOG/HAZE AND/OR FEW LOW CLOUDS ARE NOT TOTALLY OUT OF THE QUESTION. WITH GENERALLY CLEAR SKIES...EXPECT A RELATIVELY COOL NIGHT WITH LOWS IN THE UPPER 50S ACROSS THE SW TX PANHANDLE TO THE MIDDLE 60S ACROSS THE FAR ROLLING PLAINS EXPECTED. HIGHS IN THE LOWER 80S TODAY WILL BE FOLLOWED BY UPPER 80S TO LOWER 90S ON MONDAY...THANKS TO THE UA RIDGE EXPANDING ACROSS THE REGION AND THUS...AN UPTICK IN 500 MB HEIGHT FIELDS AND 850 MB TEMPS OCCUR. DRY CONDITIONS ARE EXPECTED. LONG TERM... AN UPPER LEVEL HIGH PRESSURE RIDGE WILL AMPLIFY ACROSS OUR AREA EARLY IN THE WEEK. A DISTURBANCE ALONG THE WEST COAST OF MEXICO WILL LIFT NORTHWARD INTO THE SOUTHERN ROCKIES WITH MOISTURE IMPROVEMENT OVER THE SOUTHERN HIGH PLAINS AS WELL. THE BULK OF LIFT AND INSTABILITY IS EXPECTED TO REMAIN TO OUR WEST. WE WILL HOLD ON TO SMALL THUNDER MENTION ALONG OUR WESTERN BORDER AREAS TUESDAY. QUICKLY FOLLOWING WILL BE THE OLD CLOSED UPPER LOW OFF BAJA THAT MODELS HAVE BEEN SPEEDING UP AND MAINTAINING MORE INTENSITY THROUGH THE CENTRAL ROCKIES INTO THE CENTRAL HIGH PLAINS. HEIGHTS ALOFT SHOULD FALL OVER OUR AREA TUESDAY NIGHT AND WEDNESDAY WITH DEEPER MOISTURE DRAGGING ACROSS NORTHWEST AND NORTHERN ZONES INITIALLY AS UPPER RIDGE RETREATS SOUTH AND WEST EVENTUALLY TO REFORM FURTHER WEST OVER THE SOUTHERN PLATEAU AND NORTHWEST MEXICO. MOISTURE SHOULD CONTINUE ACROSS THE AREA THURSDAY THOUGH WITHOUT SIGNIFICANT LIFT...STILL VALID FOR A LOW MENTION OF THUNDER ACROSS MUCH OF THE AREA. AS THE UPPER RIDGE REFORMS TO THE WEST ON FRIDAY...THIS MAY OPEN A WINDOW FOR THE REMNANTS OF THE CENTRAL HIGH PLAINS LOW TO DIP BACK SOUTHWARD. OUR SOLUTIONS ARE NOT AT ALL CONSISTENT ON THIS AND WE WILL RETAIN DRY FORECAST HEADING INTO NEXT WEEKEND...BUT GIVES SOMETHING TO WATCH IN THAT FAR EXTENDED TIME FRAME. AFTER AN INITIAL COUPLE OR THREE FAIRLY WARM DAYS THIS WEEK...THE COMBINATION OF IMPROVED MOISTURE AND LOWER HEIGHTS WITH LESS UPPER RIDGE INFLUENCE CONTINUE TO FAVOR ABOVE NORMAL ALTHOUGH MORE MODERATE TEMPERATURES LATE WEEK INTO THE NEXT WEEKEND. RMCQUEEN && .PRELIMINARY POINT TEMPS/POPS... FRIONA 59 88 61 83 / 0 0 0 20 TULIA 60 88 61 86 / 10 0 0 10 PLAINVIEW 60 88 60 87 / 10 0 0 10 LEVELLAND 60 87 61 86 / 0 0 0 10 LUBBOCK 60 89 63 88 / 10 0 0 10 DENVER CITY 60 87 61 85 / 0 0 10 10 BROWNFIELD 61 87 62 86 / 10 0 0 10 CHILDRESS 65 92 67 94 / 20 0 0 0 SPUR 63 90 65 91 / 10 0 0 0 ASPERMONT 65 94 68 94 / 10 0 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 14/93/14
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
205 AM EDT MON SEP 21 2015 .SYNOPSIS... A COLD FRONT WILL CONTINUE TO PUSH SOUTHEAST OF THE REGION TONIGHT ALLOWING COOL HIGH PRESSURE TO BUILD SOUTH ALONG THE EAST SIDE OF THE APPALACHIANS BEHIND THE FRONT OVERNIGHT. THIS CHANGE IN AIRMASS WILL RESULT IN LOWER TEMPERATURES OVER THE NEXT COUPLE OF DAYS. INCREASING MOISTURE ASSOCIATED WITH ONSHORE EASTERLY FLOW WILL COMBINE WITH A WEAK UPPER LEVEL DISTURBANCE TO RESULT IN ABUNDANT CLOUD COVER ACROSS THE REGION ALONG WITH THE POTENTIAL FOR AREAS OF RAIN MONDAY INTO TUESDAY. && .NEAR TERM /THROUGH TODAY/... AS OF 930 PM EDT SUNDAY... THE LATE EVENING FORECAST UPDATE WILL REFLECT ONE PRIMARY ADJUSTMENT TO THE ONGOING FORECAST. THE LATEST MESOSCALE MODELS OFFER A SOLUTION THAT REDUCES THE EXTENT THAT PRECIPITATION DEVELOPMENT WILL TAKE PLACE OVER THE EASTERN AND NORTHWESTERN PARTS OF THE AREA UNTIL AFTER ROUGHLY 200 AM MONDAY. HOWEVER...THESE LATEST SOLUTIONS ALSO CONTINUE TO CONFIRM A HIGH PROBABILITY OF PRECIPITATION ALONG AND NEAR THE CREST OF THE BLUE RIDGE THROUGH...AND AFTER...THE SAME TIME PERIOD SOUTHWEST OF ROANOKE VIRGINIA. THE LATEST FORECAST UPDATE WILL REFLECT THESE TRENDS. NO OTHER SIGNIFICANT CHANGES ARE EXPECTED. MINOR ADJUSTMENTS TO HOURLY TEMPERATURE AND DEW POINT WILL REFLECT THE LATEST OBSERVATIONS AND EXPECTED TRENDS THROUGH ROUGHLY 200 AM. AS OF 625 PM EDT SUNDAY... EARLY EVENING UPDATE WILL REFLECT A GREATER CONCENTRATION OF SHOWERS THAN ISOLATED WITHIN AN AREA AROUND MARTINSVILLE VIRGINIA...WEST TO NEAR THE CREST OF THE BLUE RIDGE. ALSO...A CLUSTER OF SHOWERS WAS SOUTH OF THIS REGION ACROSS CENTRAL STOKES COUNTY NORTH CAROLINA. THIS COLLECTION OF SHOWERS MATCHES WELL WITH A NOSE OF MORE UNSTABLE AIR WITH SURFACE BASED CONVECTIVE AVAILABLE POTENTIAL ENERGY OF 500-1000 JOULES PER KILOGRAM AND SURFACE BASED LIFTED INDICES OF -1 TO -2 C. THIS AREA...AND IMMEDIATELY DOWNSTREAM TOWARDS ROCKINGHAM COUNTY NORTH CAROLINA AND PITTSYLVANIA COUNTY VIRGINIA ARE EXPECTED TO EXPERIENCE SOMEWHAT HIGHER THAN EARLIER PROJECTED PROBABILITY OF PRECIPITATION OVER THE NEXT FEW HOURS. NO OTHER SIGNIFICANT CHANGES WERE MADE TO THE FORECAST AT THIS TIME. TWEAKS OF HOURLY TEMPERATURE...DEW POINT...WIND AND SKY COVER WERE MADE THROUGH THE LATE EVENING HOURS BASED UPON THE LATEST OBSERVATIONS AND EXPECTED TRENDS OVER THE NEXT FEW HOURS. AS OF 300 PM EDT SUNDAY... A COLD FRONT TO OUR SOUTH THIS AFTERNOON WILL CONTINUE TO PUSH SOUTHEAST IN THE ATLANTIC TONIGHT INTO MONDAY. ISOLATED TO SCATTERED CONVECTION HAS FORM IN THE UNSTABLE AIR THIS AFTERNOON MAINLY ALONG THE SOUTHERN BLUE RIDGE. SPC 18Z MESOSCALE ANAL INDICATED SBCAPE AROUND 500 J/KG ALONG THE EASTERN SLOPES OF THE BLUE RIDGE INTO NORTH CAROLINA. KFCX RADAR IMAGES INDICATED SHOWERS FORMING WITH DEEP LAYER MOIST FLUX CONVERGENCE. TRIMMED BACK THUNDERSTORMS FOR THIS AFTERNOON INTO TONIGHT...BUT ALLOWED FOR SOME ISOLATED STORMS AS HIGHLIGHTED IN THE SPC DAY ONE CONVECTIVE OUTLOOK. INITIALLY...SHAPED POPS TOWARDS A BLEND OF HRRR AND RNK WRFARW THIS AFTERNOON INTO THIS EVENING FOR CONVECTION...THEN INCREASE CHANCES WITH RAIN TONIGHT. AS HIGH PRESSURE TO OUR NORTH BUILDS SOUTHEAST TONIGHT ALONG THE EAST SIDE OF THE APPALACHIANS...A LOW LEVEL EASTERLY WIND WILL DEVELOP PROMOTING UPSLOPE CLOUDS AND THE DEVELOPMENT OF AREAS OF LIGHT RAIN AND DRIZZLE. HIGHEST POPS WILL BE ALONG THE BLUE RIDGE WHERE THE UPSLOPE LOW LEVEL UVM COMPONENT WILL BE THE GREATEST. IN SPITE OF THE PRECIPITATION...AMOUNTS ARE EXPECTED TO BE LIGHT...LESS THAN A QUARTER OF AN INCH. LOW TEMPERATURES TONIGHT WILL VARY FROM AROUND 50 DEGREES IN THE MOUNTAINS TO THE LOWER 60S IN THE PIEDMONT. ON MONDAY...AN UPPER LEVEL TROUGH WILL DEEPEN AS IT DRIFTS EASTWARD FROM NEAR THE MISSISSIPPI VALLEY TOWARD THE APPALACHIANS. MEANWHILE HIGH PRESSURE EXTENDING SOUTHWARD FROM NEW ENGLAND...WILL PUSH MOISTURE INTO THE EASTERN FACE OF THE APPALACHIANS. WIDESPREAD RAIN IS EXPECTED MONDAY...ESPECIALLY ALONG THE BLUE RIDGE. UPSLOPE FLOW COMBINED WITH RICH CLOUD COVER WILL RESULT IN COOL CONDITIONS MONDAY WITH HIGH TEMPERATURES VARYING FROM THE MID 50S IN THE MOUNTAINS TO THE MID 60S IN THE PIEDMONT. SOME WARMER TEMPERATURES MAY SLIDE INTO THE FAR WEST ALLOWING READINGS TO CLIMB TO AROUND 70 DEPENDING ON THE STRENGTH OF THE COOL WEDGE. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY/... AS OF 230 PM EDT SUNDAY... STRONG WEDGE WILL REMAIN IN PLACE MONDAY NIGHT WITH FORECAST SOUNDINGS SHOWING ENOUGH DEEP MOISTURE PER CONTINUED UPSLOPE EARLY...AND SHORTWAVE ENERGY ROTATING THROUGH UNDER THE OHIO VALLEY UPPER TROUGH TO KEEP PERIODS OF RAIN/DRIZZLE GOING OVERNIGHT. MOISTURE DEPTH MAY DECREASE SOME LATE MONDAY NIGHT AS THE FLOW TURNS MORE NORTHERLY SO GOING WITH HIGHEST CHANCE/LOW LIKELY POPS DURING THE EVENING OTHERWISE CONTINUED DAMP AND COOL OVERNIGHT. COLUMN SHOULD CONTINUE TO DRY TUESDAY INTO TUESDAY NIGHT AS THE COMBINATION OF LOW PRESSURE OFFSHORE AND HIGH PRESSURE BUILDING IN FROM THE NORTH ENHANCES A DRIER NORTH TO NE TRAJECTORY. HOWEVER WITH THE UPPER COLD POOL CLOSING OFF ACROSS THE WEST...MAY SEE ADDED SHRA BANDS IN THE AFTERNOON WITH ANY INSOLATION AS GUIDANCE SHOWING A SMALL RIBBON OF INSTABILITY FAR WEST. OTHERWISE WILL INIT WITH MORE STRATIFORM LIGHT RAIN EARLY TUESDAY...GIVING WAY TO MORE CONVECTIVE NATURE IN THE AFTERNOON WITH MAINLY CHANCE POPS MOUNTAINS WHERE SUPPORTED BY SOME NORTH/NE FLOW CONVERGENCE INTO EARLY TUESDAY EVENING BEFORE DRYING OUT OVERNIGHT. GIVEN A LITTLE MORE SUNSHINE EXPECT HIGH TEMPS TO REBOUND A LITTLE PENDING HOW FAST THE WEDGE ERODES. THUS STAYED BELOW MOS FOR HIGHS WITH MAINLY 65-70 NEAR THE BLUE RIDGE AND LOW 70S PIEDMONT AND FAR WEST. UPPER LOW SHIFTS TO THE SOUTH WEDNESDAY ALLOWING INCREASING SUBSIDENCE AND ADDED DRYING AS STRONG HIGH PRESSURE BUILDS IN FROM THE NORTH. THIS ALONG WITH A DRY NORTHERLY FLOW SHOULD RESULT IN A SUNNY AND MILDER DAY WEDNESDAY WITH HEATING OF DRY AIR PUSHING HIGHS BACK INTO THE MID/UPPER 70S OVERALL. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 1230 PM EDT SUNDAY... ENSEMBLES CONTINUE TO SHOW A MOSTLY DRY PERIOD INTO NEXT WEEKEND AS THE RESIDUAL UPPER LOW ACROSS THE CAROLINAS DURING MIDWEEK DROPS FARTHER SOUTH BEFORE RETROGRADING NW INTO THE TN VALLEY BY THE END OF THE PERIOD. THIS SHOULD ALLOW SOME DEGREE OF UPPER RIDGING TO TAKE SHAPE OVER THE MID ATLANTIC THROUGH THE END OF THE WEEK BEFORE HEIGHTS LOWER A BIT WITH THE UPPER SYSTEM SLIDING NORTHWARD. PASSING MID LEVEL TROFFINESS WELL TO THE NE WILL ALSO ALLOW A LARGE AREA OF SURFACE HIGH PRESSURE TO SPILL SOUTH LEADING TO ADDITIONAL LOW LEVEL WEDGING BY THE WEEKEND. HOWEVER STILL SOME UNCERTAINTY GIVEN THE PERSISTENT WET TREND OFF THE OPERATIONAL GFS SOLUTIONS AND A FEW OF ITS ENSEMBLE MEMBERS IN KEEPING THE CLOSED LOW SPINNING OVER THE CAROLINAS. THIS SCENARIO EVENTUALLY TAPS INTO MOISTURE WITH LOW PRESSURE OFFSHORE AND MAKES FOR QUITE AN ONSHORE TAP OF SHOWERS THROUGH MUCH OF THE PERIOD. SINCE THIS REMAINS AN OVERALL OUTLIER AT THIS POINT...WILL STAY CONSISTENT AND REMAIN CLOSER TO THE EARLIER 00Z CMC/12Z EC...AND GO MAINLY DRY EXCEPT FOR ISOLATED OROGRAPHIC AIDED SHOWERS SW FRIDAY...AND OVER SOUTHERN/CENTRAL SECTIONS SATURDAY INTO SUNDAY AS SOME LOW LEVEL MOISTURE RETURNS. OTHERWISE DRY WEDGE APPEARS TOO STRONG EVEN FOR LOW CLOUDS SO RUNNING PC/MOSTLY SUNNY WITH MORE CLOUDS BY THE WEEKEND. TEMPS REMAIN MILD BUT OVERALL STILL CLOSE TO SEASONAL NORMALS...MOSTLY 70S FOR HIGHS BUT COOL 50S AT NIGHT. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... AS OF 200 AM EDT MONDAY... DETERIORIATING AVIATION CONDITIONS THIS TAF VALID PERIOD. A WEDGE OF MOIST...COOL AIR IS IN THE PROCESS OF DEVELOPING ACROSS THE CWA AS A LARGE AREA OF HIGH PRESSURE SLIDES FROM THE EASTERN GREAT LAKES TOWARD NEW ENGLAND. CLOUDS HAVE BEEN THICKENING AND LOWERING AND THIS GENERAL TREND IS EXPECTED TO CONTINUE THROUGH THE MORNING WITH CIGS/VSBYS LOWERING INTO THE MVFR RANGE...THEN TRENDING LOWER AS LIGHT RAIN/DRIZZLE SATURATES THE BOUNDARY LAYER RESULTING IN EVENTUAL DEVELOPMENT OF IFR CIGS. WEDGE IS FORECAST TO PERSIST INTO TUESDAY...THUS LITTLE TO NO IMPROVEMENT IS EXPECTED ONCE THESE LOWER CIGS DEVELOP. WIND FLOW THE NEXT 24 HOURS WILL BE OUT OF THE NORTHEAST OR EAST...5 TO 10KTS THROUGH THE VALID TAF PD. SOME GUSTS OF 15-20 KTS ARE POSSIBLE VCNTY OF THE RIDGE TOPS. MEDIUM CONFIDENCE IN CIGS THROUGHOUT THE TAF VALID PERIOD. MEDIUM CONFIDENCE IN VSBYS THROUGHOUT THE TAF VALID PERIOD. MEDIUM TO HIGH CONFIDENCE IN WIND SPEED/DIRECTION THROUGH THE TAF VALID PERIOD. EXTENDED AVIATION DISCUSSION... THE WEDGE WILL GRADUALLY DISSIPATE BY MIDWEEK ALLOWING CONDITIONS TO RETURN TO VFR FOR MID/LATE WEEK. SOME FORECAST MODELS INDICATE THAT LOW PRESSURE MAY RETROGRADE WESTWARD FROM THE EAST COAST LATE IN THE WEEK BRINGING CLOUDS AND PRECIPITATION...BUT CONFIDENCE IS LOW AT THIS TIME AS SEVERAL MODELS DO NOT SHOW THIS POSSIBILITY...RATHER KEEPING THE SYSTEM FARTHER EAST AND OFF THE COAST AND WITH HIGH PRESSURE OVER OUR REGION. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...JH/PM NEAR TERM...DS/KK SHORT TERM...JH LONG TERM...JH AVIATION...PM
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
915 AM CDT MON SEP 21 2015 ...UPDATE TO SYNOPSIS... .SYNOPSIS... ISSUED AT 915 AM CDT MON SEP 21 2015 WV Imagery and 12Z upper air analysis indicate a weak upper level ridge of high pressure lifting northeast across the Desert Southwest. Meanwhile, the remnants of a tropical depression are lifting northeast into southeastern Arizona and southwestern New Mexico. Near the surface, a weak area of low pressure is situated across extreme southeast Colorado with an associated trough axis extending southward into the Oklahoma panhandle. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 1238 AM CDT MON SEP 21 2015 Main question is when/how many counties to go with a Dense Fog Advisory. We will likely be issuing one over the coming hours once we see some visibility observations drop. Abundant low level moisture with light southeast winds and clear skies are providing the necessary backdrop for dense fog formation, especially at the edge of the current stratus deck, which as of 0530z extended from roughly Meade to just south of Hays (there was a narrow break from Dodge City to Ashland). Temperatures today will be a real challenge, and with all this moisture in place along with a slow erosion of the expected fog/low stratus, we will probably only see temperatures topping out in the lower to mid 80s northeast of a Dighton to Dodge City to Coldwater line. Farther southwest, the temperature forecast will be unchanged with lower 90s still expected. The WRF-ARW was followed, which did a fairly good job of depicting yesterday`s cool bubble across portions of south-central Kansas. .LONG TERM...(Tuesday THROUGH Sunday) ISSUED AT 357 AM CDT MON SEP 21 2015 The global models are coming into slightly better agreement regarding the mid-week increase in precipitation chances. The ECMWF model is still the most developed, maintaining the most coherent mid level potential vorticity anomaly as the subtropical low meanders into western Kansas by Wednesday Night. The Canadian GEM is next in line and follows closer the ECMWF solution than does the GFS. As a result, the Canadian GEM and the ECMWF solutions offer the best scenario for sustained precipitation chances from early to midday Wednesday lasting into Thursday Night. There will likely be several rounds with a few breaks within the smaller scale episodes of precipitation. This does not look like a situation where severe weather will be much of a risk. Deep subtropical moisture and the lack of lower-mid tropospheric frontogenesis will both be negatives as far as severe weather potential is concerned... both limiting CAPE. As far as temperatures go, the daytime temperatures will be trending downward from previous forecast, and do not be surprised to see further decrease in forecast highs, especially Thursday. The ECMWF is quite cool on Thursday keeping all of western Kansas in the 60s. We will see if the Canadian GEM and the GFS follow suit in future runs. The subtropical disturbance will continue to wallow aimlessly across the western Kansas until it spins itself out...as the main polar jet will be way off to the north in Canada. Pronounced lower tropospheric warming will be confined to areas north of the Central High Plains it would appear, as the subtropical entity nearby will keep temperatures in check given the absence of any downslope momentum over western Kansas amidst a fairly deep, moist troposphere. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Tuesday MORNING) ISSUED AT 559 AM CDT MON SEP 21 2015 Quite a poor job by the HRRR model this morning in forecasting far too widespread and too low of visibilities across the area. The stratus development and surface winds being slightly too strong keeping mixing up may have had a part in dense fog not becoming widespread. Rather than carrying FG in prevailing groups, we`ve mentioned in in TEMPO groups only this am and will monitor for updates. The rest of the morning will be trying to capture the trend of dissipation of the IFR stratus as the models have not been great. && .PRELIMINARY POINT TEMPS/POPS... DDC 88 65 92 65 / 0 0 0 20 GCK 91 63 93 64 / 0 0 10 30 EHA 93 65 91 64 / 0 0 10 40 LBL 93 65 93 65 / 0 0 10 20 HYS 84 63 93 66 / 0 0 0 20 P28 85 65 93 67 / 0 0 0 10 && .DDC Watches/Warnings/Advisories... NONE. && $$ SYNOPSIS...JJohnson SHORT TERM...Umscheid LONG TERM...Umscheid AVIATION...Russell
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
602 AM CDT MON SEP 21 2015 ...UPDATED AVIATION SECTION... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 1238 AM CDT MON SEP 21 2015 Main question is when/how many counties to go with a Dense Fog Advisory. We will likely be issuing one over the coming hours once we see some visibility observations drop. Abundant low level moisture with light southeast winds and clear skies are providing the necessary backdrop for dense fog formation, especially at the edge of the current stratus deck, which as of 0530z extended from roughly Meade to just south of Hays (there was a narrow break from Dodge City to Ashland). Temperatures today will be a real challenge, and with all this moisture in place along with a slow erosion of the expected fog/low stratus, we will probably only see temperatures topping out in the lower to mid 80s northeast of a Dighton to Dodge City to Coldwater line. Farther southwest, the temperature forecast will be unchanged with lower 90s still expected. The WRF-ARW was followed, which did a fairly good job of depicting yesterday`s cool bubble across portions of south-central Kansas. .LONG TERM...(Tuesday THROUGH Sunday) ISSUED AT 357 AM CDT MON SEP 21 2015 The global models are coming into slightly better agreement regarding the mid-week increase in precipitation chances. The ECMWF model is still the most developed, maintaining the most coherent mid level potential vorticity anomaly as the subtropical low meanders into western Kansas by Wednesday Night. The Canadian GEM is next in line and follows closer the ECMWF solution than does the GFS. As a result, the Canadian GEM and the ECMWF solutions offer the best scenario for sustained precipitation chances from early to midday Wednesday lasting into Thursday Night. There will likely be several rounds with a few breaks within the smaller scale episodes of precipitation. This does not look like a situation where severe weather will be much of a risk. Deep subtropical moisture and the lack of lower-mid tropospheric frontogenesis will both be negatives as far as severe weather potential is concerned... both limiting CAPE. As far as temperatures go, the daytime temperatures will be trending downward from previous forecast, and do not be surprised to see further decrease in forecast highs, especially Thursday. The ECMWF is quite cool on Thursday keeping all of western Kansas in the 60s. We will see if the Canadian GEM and the GFS follow suit in future runs. The subtropical disturbance will continue to wallow aimlessly across the western Kansas until it spins itself out...as the main polar jet will be way off to the north in Canada. Pronounced lower tropospheric warming will be confined to areas north of the Central High Plains it would appear, as the subtropical entity nearby will keep temperatures in check given the absence of any downslope momentum over western Kansas amidst a fairly deep, moist troposphere. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Tuesday MORNING) ISSUED AT 559 AM CDT MON SEP 21 2015 Quite a poor job by the HRRR model this morning in forecasting far too widespread and too low of visibilities across the area. The stratus development and surface winds being slightly too strong keeping mixing up may have had a part in dense fog not becoming widespread. Rather than carrying FG in prevailing groups, we`ve mentioned in in TEMPO groups only this am and will monitor for updates. The rest of the morning will be trying to capture the trend of dissipation of the IFR stratus as the models have not been great. && .PRELIMINARY POINT TEMPS/POPS... DDC 85 64 91 65 / 0 0 10 20 GCK 89 63 92 64 / 0 0 20 30 EHA 93 65 90 64 / 0 0 30 40 LBL 91 65 92 65 / 0 0 10 20 HYS 81 63 92 66 / 0 0 10 20 P28 85 64 92 67 / 0 0 0 10 && .DDC Watches/Warnings/Advisories...NONE. && $$ SHORT TERM...Umscheid LONG TERM...Umscheid AVIATION...Russell
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1055 AM CDT MON SEP 21 2015 .UPDATE... SATELLITE TRENDS INDICATE THAT THE OVERCAST SKIES WILL LINGER OVER THE AREA THROUGH MUCH OF THE DAY. THERE WILL ALSO BE CONTINUED RAIN SHOWERS THROUGH THE AFTERNOON...WITH COVERAGE EXPECTED TO INCREASE OVER THE SOUTHERN HALF OF THE FORECAST AREA DURING THE AFTERNOON HOURS. HAVE BUMPED UP POPS FOR THE SOUTHERN PART OF THE CWA TO HIGH END CHANCE TO REFLECT THIS RISK. TEMPERATURES TRENDS ARE COOLER THAN EXPECTED GIVEN THE PERSISTENT CLOUD COVER...WITH READINGS ACROSS THE NORTHERN HALF OF THE FORECAST AREA A GOOD 5 DEGREES COOLER THAN EXPECTED. WITH CLOUD COVER EXPECTED TO LINGER THROUGH THE AFTERNOON HOURS...HAVE LOWERED HIGHS FOR THE DAY BY A FEW DEGREES ON AVERAGE. HIGHS SHOULD ONLY PEAK IN THE LOWER TO MIDDLE 80S OVER MUCH OF THE AREA THIS AFTERNOON. 32 && .PREV DISCUSSION... /ISSUED 912 AM CDT MON SEP 21 2015/ UPDATE... UPDATED RAIN CHANCES TO SHOW A GRADIENT FROM 100 PERCENT NORTH TO 25 TO 30 PERCENT SOUTH TO BLEND WITH CURRENT RADAR TRENDS AND LATEST HRRR RUNS THIS MORNING. DRIER AIR BEHIND COLD FRONT WILL START TO DIMINISH RAIN COVERAGE IN THE FAR NORTH/NORTHWEST LATE THIS MORNING...SO TAPER TRENDS BACK TO THE ORIGINAL MORNING FORECAST. REMAINDER OF FORECAST LOOKS GOOD AT THIS TIME. 22/TD PREV DISCUSSION... /ISSUED 252 AM CDT MON SEP 21 2015/ SHORT TERM... SHOWERS AND A FEW TS WILL BE POSSIBLE TODAY AS AN 850MB TROUGH MOVES THROUGH. THE SFC COLD FRONT WILL MOVE THROUGH TUESDAY MORNING AS THE AIR MASS DRIES VIA DP TEMPS FALLING BACK INTO THE 50S. BUT THIS SHOULD BE SHORT LIVED AS DEEPER MOISTURE WILL MOVE IN FROM THE EAST BY WED EVENING. THE DEEP MOISTURE WILL NOT MAKE A LOT OF HEADWAY THOUGH AND GETS HELD NEAR THE LOWER PEARL RIVER. A NEW SURGE OF DRY AIR MOVES BACK INTO THE AREA TO KEEP THE DEEPER MOISTURE OFFSHORE BY THURSDAY EVENING. LONG TERM... THE WEEKEND LOOKS TO BE DRY FOR THE MOMENT AND WITH DP TEMPS BACK INTO THE MID 50S...AMBIENT TEMPS MAY MAKE THIGS FEEL NICE OR COOL TO SOME. DEEP MOISTURE ONCE AGAIN WILL MOVE IN FROM THE EAST BY THE START OF NEXT WEEK BRINGING THE SHOWER ACTIVITY BACK WITH IT. ANOTHER DEEP UPPER TROUGH WILL BE DIGGING INTO THE GULF BY NEXT WEEK SO WE WILL HAVE TO SEE EXACTLY WHERE THE SFC FRONT SETS UP OVER THE DEEP SOUTH. AVIATION...A WEAK FRONTAL BOUNDARY CONTINUE TO SLOWLY PUSH SOUTH ACROSS THE AREA THIS MORNING...AND WILL CONTINUE TO DO SO BEFORE CLEARING THE COAST AND EVENTUALLY BECOMING DIFFUSE. MAINLY MID AND UPPER LEVEL CLOUDS ARE BEING OBSERVED ACROSS THE REGION IN ADVANCE OF A SHORTWAVE TROUGH. A FEW POST FRONTAL SHRA WERE ALSO BEING OBSERVED BUT ALL WERE STILL OUT OF THE CWA. VFR CONDITIONS WILL GENERALLY PREVAIL AT THE TERMINALS THROUGH THE TAF FORECAST PERIOD BUT CANT RULE OUT TEMPO MVFR DUE TO SHRA. /CAB/ MARINE...THE WEAK FRONT IS SLOWLY MOVING SOUTH THROUGH THE CWA AND HAS ALREADY APPROACHED THE MS COAST AND SHOULD ENTER ALL OF THE COASTAL WATERS LATE THIS MORNING. WINDS WILL VEER AROUND TO OFFSHORE AND COULD RANGE FROM 10-13KTS AT TIMES BUT WITH THE LACK OF ANY REAL SIGNIFICANT CAA NOT EXPECTING STRONG WINDS. THE FRONT WILL WASHOUT QUICKLY BASICALLY LEAVING THE AREA B/T BROAD LOW PRESSURE IN THE SRN GULF AND BROAD HIGH PRESSURE DOMINATING MUCH OF THE ERN CONUS. THIS WILL LEAD TO PERSIST MODERATE ERLY WINDS THROUGH MUCH OF THE WEAK. MDLS ARE CONTINUING TO INDICATE THE POSSIBILITY OF A WEAK SFC LOW DEVELOPING NEAR THE YUCATAN LATE NEXT WEEKEND...SO WILL NEED TO CONTINUE TO WATCH THIS POSSIBLE DEVELOPMENT. /CAB/ DECISION SUPPORT... DSS CODE....GREEN. DEPLOYED...NONE. ACTIVATION...NONE. ACTIVITIES...NONE. DECISION SUPPORT SERVICES (DSS) CODE LEGEND GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH VISIBILITY EVENT YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES RED = FULL ENGAGEMENT FOR MODERATE RISK SVR AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE && .PRELIMINARY POINT TEMPS/POPS... MCB 85 65 88 65 / 100 10 0 0 BTR 86 68 90 67 / 50 10 0 0 ASD 84 68 89 70 / 60 20 0 0 MSY 85 72 88 73 / 30 20 0 0 GPT 83 69 89 71 / 60 20 0 0 PQL 84 67 89 70 / 60 20 0 0 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...NONE. GM...NONE. MS...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
912 AM CDT MON SEP 21 2015 .UPDATE... UPDATED RAIN CHANCES TO SHOW A GRADIENT FROM 100 PERCENT NORTH TO 25 TO 30 PERCENT SOUTH TO BLEND WITH CURRENT RADAR TRENDS AND LATEST HRRR RUNS THIS MORNING. DRIER AIR BEHIND COLD FRONT WILL START TO DIMINISH RAIN COVERAGE IN THE FAR NORTH/NORTHWEST LATE THIS MORNING...SO TAPER TRENDS BACK TO THE ORIGINAL MORNING FORECAST. REMAINDER OF FORECAST LOOKS GOOD AT THIS TIME. 22/TD && .PREV DISCUSSION... /ISSUED 252 AM CDT MON SEP 21 2015/ SHORT TERM... SHOWERS AND A FEW TS WILL BE POSSIBLE TODAY AS AN 850MB TROUGH MOVES THROUGH. THE SFC COLD FRONT WILL MOVE THROUGH TUESDAY MORNING AS THE AIR MASS DRIES VIA DP TEMPS FALLING BACK INTO THE 50S. BUT THIS SHOULD BE SHORT LIVED AS DEEPER MOISTURE WILL MOVE IN FROM THE EAST BY WED EVENING. THE DEEP MOISTURE WILL NOT MAKE A LOT OF HEADWAY THOUGH AND GETS HELD NEAR THE LOWER PEARL RIVER. A NEW SURGE OF DRY AIR MOVES BACK INTO THE AREA TO KEEP THE DEEPER MOISTURE OFFSHORE BY THURSDAY EVENING. LONG TERM... THE WEEKEND LOOKS TO BE DRY FOR THE MOMENT AND WITH DP TEMPS BACK INTO THE MID 50S...AMBIENT TEMPS MAY MAKE THIGS FEEL NICE OR COOL TO SOME. DEEP MOISTURE ONCE AGAIN WILL MOVE IN FROM THE EAST BY THE START OF NEXT WEEK BRINGING THE SHOWER ACTIVITY BACK WITH IT. ANOTHER DEEP UPPER TROUGH WILL BE DIGGING INTO THE GULF BY NEXT WEEK SO WE WILL HAVE TO SEE EXACTLY WHERE THE SFC FRONT SETS UP OVER THE DEEP SOUTH. AVIATION...A WEAK FRONTAL BOUNDARY CONTINUE TO SLOWLY PUSH SOUTH ACROSS THE AREA THIS MORNING...AND WILL CONTINUE TO DO SO BEFORE CLEARING THE COAST AND EVENTUALLY BECOMING DIFFUSE. MAINLY MID AND UPPER LEVEL CLOUDS ARE BEING OBSERVED ACROSS THE REGION IN ADVANCE OF A SHORTWAVE TROUGH. A FEW POST FRONTAL SHRA WERE ALSO BEING OBSERVED BUT ALL WERE STILL OUT OF THE CWA. VFR CONDITIONS WILL GENERALLY PREVAIL AT THE TERMINALS THROUGH THE TAF FORECAST PERIOD BUT CANT RULE OUT TEMPO MVFR DUE TO SHRA. /CAB/ MARINE...THE WEAK FRONT IS SLOWLY MOVING SOUTH THROUGH THE CWA AND HAS ALREADY APPROACHED THE MS COAST AND SHOULD ENTER ALL OF THE COASTAL WATERS LATE THIS MORNING. WINDS WILL VEER AROUND TO OFFSHORE AND COULD RANGE FROM 10-13KTS AT TIMES BUT WITH THE LACK OF ANY REAL SIGNIFICANT CAA NOT EXPECTING STRONG WINDS. THE FRONT WILL WASHOUT QUICKLY BASICALLY LEAVING THE AREA B/T BROAD LOW PRESSURE IN THE SRN GULF AND BROAD HIGH PRESSURE DOMINATING MUCH OF THE ERN CONUS. THIS WILL LEAD TO PERSIST MODERATE ERLY WINDS THROUGH MUCH OF THE WEAK. MDLS ARE CONTINUING TO INDICATE THE POSSIBILITY OF A WEAK SFC LOW DEVELOPING NEAR THE YUCATAN LATE NEXT WEEKEND...SO WILL NEED TO CONTINUE TO WATCH THIS POSSIBLE DEVELOPMENT. /CAB/ DECISION SUPPORT... DSS CODE....GREEN. DEPLOYED...NONE. ACTIVATION...NONE. ACTIVITIES...NONE. DECISION SUPPORT SERVICES (DSS) CODE LEGEND GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH VISIBILITY EVENT YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES RED = FULL ENGAGEMENT FOR MODERATE RISK SVR AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE && .PRELIMINARY POINT TEMPS/POPS... MCB 88 65 88 65 / 100 10 0 0 BTR 88 68 90 67 / 40 10 0 0 ASD 85 68 89 70 / 30 20 0 0 MSY 85 72 88 73 / 30 20 0 0 GPT 84 69 89 71 / 30 20 0 0 PQL 83 67 89 70 / 30 20 0 0 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...NONE. GM...NONE. MS...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
726 AM EDT MON SEP 21 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 507 AM EDT MON SEP 21 2015 WV IMAGERY AND RAP ANALYSIS INDICATED ZONAL MID/UPPER LEVEL FLOW FROM THE PAC NW INTO NRN ONTARIO AND A WEAK TROUGH OVER THE GREAT LAKES. A VIGOROUS SHRTWV TROUGH WAS MOVING THROUGH SRN ALBERTA. AT THE SFC...INCREASING SRLY FLOW PREVAILED ACROSS THE UPPER MS VALLEY INTO THE WRN LAKES BETWEEN HIGH PRES OVER NEW ENGLAND AND A TROUGH EXTENDING INTO THE PLAINS FROM LOW PRES OVER SRN SASK/MANITOBA. THE WAA PATTERN SUPPORTED ONLY PATCHY MID CLOUDS FROM WRN LAKE SUPERIOR THROUGH WI. TODAY...ABUNDANT SUNSHINE AND MIXING THROUGH 850 MB TEMPS CLIMBING INTO THE 10C-12C RANGE WILL SUPPORT MAX TEMPS IN THE LOW TO MID 70S. SLIGHTLY WARMER CONDITIONS WILL AGAIN PREVAIL IN DOWNSLOPE FLOW LOCATIONS ALONG LAKE SUPERIOR. FCST WINDS THROUGH THE MIDDLE AND UPPER PORTION OF THE MIXED LAYER SUPPORT WIND GUSTS INTO THE 20-25 MPH RANGE WITH SOME 25-30 MPH GUSTS OVER THE WEST. TONIGHT...AS THE VIGOROUS SHRTWV TROUGH AND ASSOCIATED DEEP SFC LOW LIFTS FROM NRN MANITOBA TO HUDSON BAY A COLD FRONT WILL BE DRAGGED THROUGH THE NRN LAKES. GIVEN THE ABSENCE OF DEEP MOISTURE...ONLY MODEST MOISTURE TRANSPORT ALONG THE FRONT AS WELL AS THE STRONGEST MID LEVEL FORCING REMAINING WELL TO THE N OVER NRN ONTARIO (SLIGHT HEIGHT RISES ARE FCST OVER THE NRN LAKES TONIGHT)...WILL CONTINUE TO MENTION ONLY LOWER END CHANCE POPS FOR SHRA/TSRA OVER NORTHWEST HALF LATE TONIGHT. MUCAPE VALUES INTO THE 500-1000 J/KG RANGE WILL SUPPORT TSRA CHANCES BUT WILL BE MARGINAL FOR THE POTENTIAL OF ANY STRONGER STORMS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 346 AM EDT MON SEP 21 2015 LIMITED CHANGES IN THE OVERALL LONG TERM FORECAST FROM 24 HOURS AGO...AS THE UPPER JET TRACKS FROM WEST TO EAST ACROSS SOUTHERN CANADA THROUGH THE LATER PART OF THIS WEEK BEFORE AMPLIFYING OVER CENTRAL CANADA FOR NEXT WEEKEND. THAT LOCATION OF THE JET WILL KEEP THE NORMAL (MIDDLE OF THIS WEEK) TO ABOVE NORMAL TEMPERATURES (THIS WEEKEND) IN PLACE THROUGHOUT THE FORECAST PERIOD. THERE ARE TWO OPPORTUNITIES FOR RAIN DURING THIS FORECAST PERIOD...WITH THE FIRST TIED TO THE COLD FRONT DROPPING SOUTHEAST ACROSS THE AREA ON TUESDAY MORNING. THE COMBINATION OF LIMITED MOISTURE AND UPPER LEVEL SUPPORT SHOULD ONLY LEAD TO ISOLATED SHOWERS DROPPING SOUTHEAST ACROSS THE CENTRAL/EASTERN U.P. AS THE FRONT MOVES THROUGH THAT AREA ON TUESDAY. DID CONTINUE TO MENTION A SLIGHT CHANCE OF THUNDER DUE TO THE THIN REGION OF WEAK INSTABILITY AHEAD OF THE FRONT. CANADIAN HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND THE FRONT AND SHOULD LEAD TO MOSTLY CLEAR SKIES OVER THE WESTERN U.P. TUESDAY AFTERNOON AND THE REST OF THE AREA ON TUESDAY NIGHT. THE NEXT OPPORTUNITY FOR RAIN WILL COME FROM BROAD WARM AIR ADVECTION DEVELOPING ON TUESDAY NIGHT IN THE MID-UPPER MISSISSIPPI VALLEY THAT WILL LIFT NORTH-NORTHEAST INTO THE WESTERN CWA ON WEDNESDAY. THERE SHOULD BE PLENTY OF MOISTURE TO WORK WITH THIS AS EXISTING MOISTURE IN THE PLAINS COMBINES WITH THE REMNANTS OF TROPICAL DEPRESSION SIXTEEN-E CURRENTLY NEAR THE BAJA PENINSULA. THE LATEST TRENDS IN THE MODELS KEEPS MUCH OF THE ENERGY FROM THE TROPICAL REMNANTS IN THE CENTRAL PLAINS...SO THE PRECIPITATION WILL BE TIED TO THAT INITIAL SURGE OF WARM AIR ADVECTION ON WEDNESDAY INTO WEDNESDAY NIGHT. THAT SURGE WILL BE OVER NORTHEAST MINNESOTA INTO NORTHWEST WISCONSIN ON WEDNESDAY MORNING AND THEN SLIDE EAST INTO WESTERN LAKE SUPERIOR AND THE WESTERN U.P. THROUGH THE DAY ON WEDNESDAY. WILL FOCUS THE HIGHEST POPS IN THAT AREA AND THEN SLOWLY DIMINISH THEM AS THE FORCING WEAKENS AND MOVES EAST ACROSS THE REST OF THE CWA WEDNESDAY NIGHT INTO THURSDAY. MODELS SHOWING PWAT VALUES RISING TOWARDS 1.5 INCHES...WHICH IS WELL ABOVE NORMAL AND LEADS TO THE POTENTIAL FOR LOCALLY HEAVY RAIN OVER WESTERN LAKE SUPERIOR AND THE WESTERN U.P WITH ANY EMBEDDED THUNDERSTORMS. A 1036MB HIGH MOVING INTO NORTHERN ONTARIO ON THURSDAY WILL EXTEND A RIDGE SOUTH TOWARDS LAKE SUPERIOR THURSDAY INTO THURSDAY NIGHT. THAT WILL SHIFT THE LOW LEVEL FLOW TO THE NORTHEAST AND START TO BRING DRIER AIR INTO THE AREA. EXPECT THE DIMINISHING UPPER LEVEL SUPPORT AND GREATER INFLUENCE OF THE HIGH TO CONTINUE INTO THURSDAY NIGHT AS THE HIGH MOVES OVER JAMES BAY. THAT SHOULD REALLY DIMINISH PRECIPITATION CHANCES HEADING INTO FRIDAY...ALTHOUGH THERE COULD BE ENOUGH LINGERING LOW LEVEL MOISTURE TO SUPPORT SOME SHOWERS OVER THE WESTERN U.P. ON THE EDGE OF THE RIDGE. AT THIS POINT...THE WEEKEND LOOKS DRY WITH THE UPPER RIDGE BUILDING OVER CENTRAL CANADA AND THE SURFACE HIGH DROPPING SOUTHEAST INTO THE NEW ENGLAND STATES. THIS WILL KEEP THE UPPER GREAT LAKES REGION UNDER THE WESTERN EDGE OF THE SURFACE RIDGE AND WITH MIXING TO 875MB TEMPS AROUND 10C ON SATURDAY WOULD SUPPORT HIGHS IN THE LOW 70S AND THEN SLIGHTLY HIGHER TEMPS ON SUNDAY WITH A LITTLE BETTER MIXING. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 725 AM EDT MON SEP 21 2015 A DRY SSW FLOW AROUND HIGH PRES MOVING INTO THE NE STATES WILL BRING VFR CONDITIONS TO ALL 3 TAF SITES THROUGH THIS EVENING. THE ARRIVAL OF A FRONT LATE TONIGHT MAY PRODUCE SCT SHRA LATE TONIGHT BUT IS NOT EXPECTED TO BE HEAVY ENOUGH TO IMPACT VSBY. A THUNDERSTORMS MAY ALSO BE POSSIBLE BUT THE PROB IS TOO LOW TOO MENTION. GUSTY SOUTH WINDS ARE EXPECTED TODAY AND SHOULD PERSIST TONIGHT WITH A TIGHT PRES GRADIENT OVER THE AREA. THIS SHOULD MINIMIZE LLWS POTENTIAL WITH A LOWER CHANCE OF DEVELOPING A LOW LEVEL INVERSION. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 520 AM EDT MON SEP 21 2015 HIGH PRESSURE OVER THE LOWER GREAT LAKES WILL SLOWLY EXIT ACROSS THE NEW ENGLAND AS A LOW OVER MANITOBA DEEPENS AND LIFTS NE THROUGH HUDSON BAY TONIGHT THROUGH TUESDAY. AS A RESULT...AN INCREASING PRES GRADIENT WILL SUPPORT S WINDS IN THE 20-25 KNOT RANGE TODAY AND TONIGHT. EXPECT THE LOW TO DRAG A COLD FRONT ACROSS LAKE SUPERIOR TONIGHT THROUGH TUE. BEHIND THE LOW...HIGH PRESSURE ACROSS NORTH DAKOTA TUE MORNING WILL BUILD OVER LAKE SUPERIOR TUE AFTERNOON...BEFORE EXPANDING ACROSS NRN ONTARIO WED. A RIDGE WILL REMAIN THROUGH FRIDAY...BEING REINFORCED BY AN ADDITIONAL AREA OF HIGH PRESSURE SETTLING ACROSS NRN ONTARIO THURSDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...JLB MARINE...JLB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
713 AM CDT MON SEP 21 2015 .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 330 AM CDT MON SEP 21 2015 THE PRIMARY FORECAST CONCERNS IN THIS PERIOD ARE PCPN CHANCES... ESPECIALLY FOR WED...AND TEMPERATURES THE NEXT FEW DAYS. SECONDARY CONCERN TODAY IS COVERAGE OF LOW CLOUDS TODAY. MAIN FEATURES FROM UPPER LEVEL CHARTS LAST EVENING WERE A 115 KT JET MAX AT 300 MB PUSHING EWD INTO SRN BC AND A MID LEVEL SHORTWAVE TROUGH ASSOCIATED WITH THAT JET MAX. 12 HOUR HEIGHT FALLS OF UP TO 80 METERS WERE NOTED IN BC AT CWXS AT 500 MB. LATEST WATER VAPOR LOOP IN COMBINATION WITH MOST RECENT RUC MODEL INITIALIZATION SHOWED THESE HAD MOVED INTO SRN ALTA AS OF 08Z. THE OTHER FEATURE OF CONCERN IN STLT IMAGERY WAS THE MOISTURE FROM TD16 MOVING NWD TOWARD SRN AZ. TODAY...LOW CLOUDS WILL BE PROBLEMATIC. THESE WERE CURRENTLY DOWN ACROSS KS AND SOME OF THE SHORT RANGE MODELS MOVE/DEVELOP THESE UP INTO OUR AREA. HOW LONG THEY STAY AROUND WILL HAVE AN IMPACT ON HIGHS TODAY...AND FOR NOW FELT MOST SPOTS WOULD STAY IN THE UPPER 70S...WITH SOME LOWER 80S NORTH. WE WILL HAVE SOME MIXING WITH THE SLY FLOW...BUT THAT MAY ONLY BE TO ABOUT 875 MB. LOW CLOUDS MAY MOVE BACK IN TONIGHT. WE HAVE HAD BEEN CARRYING A SLIGHT CHANCE OF TSTMS...BUT LOOKING AT THINGS CLOSER THE ELEVATED INSTABILITY MAY NOT BE REALIZED. IT MAY END UP BEING DRIZZLE IF ANYTHING. FOR NOW...BACKED OFF TO JUST A SLIGHT CHANCE OF SHOWERS. LOWS SHOULD BE HELD UP WITH SLY FLOW AND AN INCREASE IN LOW LEVEL MOISTURE. MOS GUIDANCE SEEMS REASONABLE WITH LOWER AND MID 60S. THE 00Z NAM SHOWED SOME TSTMS DEVELOPING TUE MORNING OVER PARTS OF ERN NE...AND THAT SCENARIO SEEMS PLAUSIBLE WITH DECENT MID LEVEL LAPSE RATES AND ELEVATED INSTABILITY. TEMPERATURES SHOULD WARM INTO THE 80S IN THE AFTN. KEPT A SLIGHT CHANCE OF TSTMS FOR TUE NIGHT INTO WED MORNING... AS PW VALUES INCREASE TO OVER 1.50 INCHES...BUT BETTER FOCUS MAY BE MORE IN ERN SD/NWRN IA/SWRN MN. THREAT FOR STRONG STORMS AND LOCALLY HEAVY RAIN WILL BE INCREASING IN OUR WRN COUNTIES BY LATE WED AFTN. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 330 AM CDT MON SEP 21 2015 HEAVY RAIN THREAT WITH STRONG STORMS MAY LINGER INTO AT LEAST WED EVENING...WITH CHANCES HIGHEST WEST OF A LINE FROM BEATRICE AND LINCOLN TOWARD WAYNE. DETAILS ON THIS SHOULD BECOME MORE CLEAR BY TOMORROW. SYSTEM THEN SOMEWHAT STALLS OUT OVER THE CNTRL PLAINS THU BEFORE SLOWLY WEAKENING. HAVE SOME POPS MENTIONED UNTIL FRI... THEN IT LOOKS MAINLY DRY. TEMPERATURES SHOULD BE AT OR ABOVE NORMAL THE WHOLE WEEK. && .AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 640 AM CDT MON SEP 21 2015 STRATUS THIS MORNING WITH IFR/PATCHY LIFR CIGS SHOULD AFFECT KLNK/KOMA/KOFK THROUGH 16-19Z. AS SOUTH WINDS INCREASE TO 12-16KTS AND GUSTY...THIS SHOULD HELP THESE LOW CLOUDS MIX OUT. THE WINDS WILL DECREASE AFTER 00Z AND COULD SEE STRATUS RE- DEVELOP 06-12Z WITH SOME DRIZZLE OR LIGHT RAIN. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...MILLER LONG TERM...MILLER AVIATION...ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
959 AM CDT MON SEP 21 2015 .UPDATE... ISSUED AT 958 AM CDT MON SEP 21 2015 FCST ON TRACK. HRRR SFC TEMPS RISE TO AROUND 90 IN THE MID RRV RIGHT AHEAD OF FRONT LATER TODAY. THIS HANDLED WELL IN FCST SO NO CHANGES. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 330 AM CDT MON SEP 21 2015 CHALLENGE FOR TODAYS FORECAST IS TEMPS AND TIMING OF FROPA AND WIND IN ITS WAKE. THE BEST PREFORMING MODEL GUIDANCE HAS MAX TEMPS TODAY IN THE MID AND UPPER 80S...SOME LOCATIONS REACHING 90...AS SOUTHWEST SFC WINDS MIX DOWN 20C FROM 850MB ALONG AND WEST OF THE VALLEY. SUSTAINED WINDS ACROSS THE NORTHERN FA WILL PEAK AROUND 25KTS NEAR WIND ADVISORY CRITERIA...SHORT DURATION AND RELATIVELY SMALL AREA PRECLUDES A NEED FOR A HEADLINE AT THIS TIME. DRY FROPA PUSHES THROUGH OVERNIGHT WITH MUCH COOLER CONDITIONS SET FOR TOMORROW WITH MAX TEMPS 20 TO 25 DEGREES COOLER. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 330 AM CDT MON SEP 21 2015 TUESDAY NIGHT INTO WEDNESDAY A WARM FRONT AND AN INCREASE OF MOISTURE LIFTS INTO THE SOUTHERN PARTS OF THE AREA ON THE NOSE OF 30 TO 40KT LLJ. SPC HAS THIS AREA IN A MARGINAL RISK OF SEVERE IN THE DAY 2 CONVECTIVE OUTLOOK. MOST LIKELY PCPN WILL BE CONFINED TO THE SOUTHEASTERN HALF OF THE CWFA AS SHORT WAVE LIFTS SLOWLY TO THE EAST IN THE MODERATE TO WEAK FLOW ALOFT. THURSDAY THROUGH SUNDAY...THERE CONTINUES TO BE VARIATION ON HOW MODELS HANDLE THE WEAK EMBEDDED SHORTWAVE THEY HAVE COMING OVER THE TOP OF THE RIDGE AND TOWARDS THE NORTHERN PLAINS ON THURSDAY. THE ECMWF KEEPS MOST OF THE ACTIVITY TO THE SOUTH...WHILE THE GFS IS MUCH MORE WET. WILL KEEP THE BLENDED CHANCE POPS GOING FOR NOW. THE UPPER FLOW WILL BEGIN TO PICK UP FROM THE SOUTHWEST AS A STRONG UPPER TROUGH DIGS INTO THE PACIFIC NORTHWEST. BY THE END OF THE PERIOD...MODELS DIVERGE ON HOW THEY HANDLE THE FIRST NORTHERN BRANCH SHORTWAVE...WITH THE GFS SLOWER AND WETTER OVER THE WEEKEND. WITH HIGH UNCERTAINTY...WILL KEEP BLENDED POPS GOING WITH A DRIER PERIOD SATURDAY AND LOW POPS FOR SUNDAY. TEMPS SHOULD SEE A WARMING TREND THROUGH THE WEEKEND WITH WELL ABOVE AVERAGE TEMPS FOR NEXT WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 622 AM CDT MON SEP 21 2015 VFR WITH WINDS TURNING FROM SOUTH TO NW TODAY AS A FRONTAL PASSAGE PUSHES ACROSS THE AREA THIS AFTN AND EVENING. SW TO W 15 TO 20MPH SUSTAINED WINDS WILL GUST 20 TO 30MPH PEAKING WITH FRONTAL PASSAGE. WINDS WILL DECOUPLE RATHER QUICKLY TONIGHT. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...RIDDLE SHORT TERM...JK LONG TERM...JK/JR AVIATION...JK
AREA FORECAST DISCUSSION
NWS NORMAN OK
1102 AM CDT MON SEP 21 2015 .DISCUSSION... FOG AND LOW CLOUDS HAVE DIMINISHED IN CENTRAL OKLAHOMA, BUT IS ONLY SLOWLY DISSIPATING IN SOUTHWEST OKLAHOMA AND ADJACENT PARTS OF TEXAS. THE SAME IS TRUE FOR PART OF NORTH CENTRAL OKLAHOMA NEAR THE KANSAS BORDER. TEMPERATURE AND WEATHER GRIDS WERE ADJUSTED TO ACCOMMODATE THIS AND FORECAST A SLOWER RISE IN EARLY AFTERNOON TEMPERATURES IN THESE AREAS. HRRR TEMPERATURES WERE LOADED AND SLIGHT MODIFIED FOR THESE AREAS. OTHERWISE, THE HEAT RETURNS THIS AFTERNOON TO PART OF WESTERN OKLAHOMA AND ADJACENT PARTS OF TEXAS. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 84 66 90 67 / 10 0 0 0 HOBART OK 89 67 93 68 / 0 0 0 0 WICHITA FALLS TX 91 68 94 68 / 0 0 0 0 GAGE OK 92 66 93 67 / 0 0 0 10 PONCA CITY OK 83 66 89 68 / 10 0 0 0 DURANT OK 88 67 92 67 / 10 0 0 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 04/09
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
652 AM EDT MON SEP 21 2015 .SYNOPSIS... A WEAK UPPER DISTURBANCE COULD BRING SOME UNSETTLED CONDITIONS TO SOUTHERN AREAS TODAY AND TUESDAY...OTHERWISE THE WEEK WILL BE DOMINATED BY HIGH PRESSURE AND MODERATING TEMPERATURES. && .NEAR TERM /THROUGH TONIGHT/... THE NEAR TERM WILL BE DOMINATED BY AN AMPLIFYING UPPER TROUGH MOVING INTO THE OHIO VALLEY...AND LOW LEVEL FLOW THAT WILL TAKE ON A TRAJECTORY OFF THE MID ATLANTIC COAST. MODELS HAVE BEEN CONSISTENT IN WANTING TO BRING CLOUDS AND THE CHANCE FOR SOME LIGHT RAIN OR POSSIBLY EVEN DRIZZLE OVER SOUTHERN SECTIONS...PERHAPS AS FAR NORTH AS THE CENTRAL MOUNTAINS AND MID SUSQ VALLEY...TODAY AND EARLY TUESDAY UNDER THE WEAK BUT PERSISTENT LOW LEVEL ISENTROPIC LIFT. SO FAR THERE IS NOT MUCH GOING ON UPSTREAM TO GET EXCITED ABOUT...WITH LOW CLOUDS JUST HAVING BEGUN TO ENCROACH ON THE NJ COAST. THE DIFFERENT FLAVORS OF THE WRF SHOW THE LIGHT PRECIP DEVELOPING FROM SOUTH TO NORTH MAINLY AFTER MID DAY OR EVEN MID AFTERNOON...WHILE THE HRRR CONSISTENTLY WANTS TO BRING LIGHT PRECIP NORTH BEFORE THE MORNING IS OUT. THIS IDEA OF LIGHT QPF IS BACKED UP BY THE SREF AND GEFS AS WELL. REGARDLESS OF THE SENSIBLE WEATHER CONCERNS FOR TODAY...IT WILL BE A COOLER DAY THAN SUNDAY OVER MOST OF THE AREA. TEMPS WILL AVERAGE IN THE MID TO UPPER 60S REGION WIDE. COOLER THAN SUNDAY OVER THE CLOUDIER SOUTH...BUT A BIT WARMER THAN SUNDAY OVER THE SUNNIER NORTH. IT SHOULD REMAIN FAIR OVER THE NORTH TONIGHT...WHILE CLOUDY AND DAMP CONDITIONS DOMINATE THE CENTRAL AND SOUTHERN AREAS. THE CHANCE FOR SOME LIGHT RAIN OR DRIZZLE WILL CONTINUE...BUT OVERALL PRECIP AMOUNTS WILL REMAIN ON THE MEAGER SIDE. && .SHORT TERM /TUESDAY/... THE BEST CHANCE FOR RAIN WILL BE THE FIRST HALF OF TUESDAY AND OVER SOUTHERN AREAS AS THE LAST VESTIGES OF THE WEAK LOW LEVEL UPSLOPE FLOW FINALLY BEGINS TO RELAX...AND THE MASSIVE RIDGE FROM OLD MEXICO UP INTO THE CENTRAL US BEGINS TO POKE ITS NOSE INTO THE LOCAL AREA. LOOKS FOR BRIGHTENING SKIES...SLOWER TO IMPROVE OVER THE SOUTH...WITH HIGHS MAKING BACK INTO THE UPPER 60S AND LOWER 70S IN MOST AREAS. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... THE EXTENDED FORECAST LOOKS LIKE WE WILL BE THE BENEFICIARIES OF THE GOOD PART OF A DEVELOPING REX BLOCK. MED RANGE GUIDANCE IS IN GOOD AGREEMENT WITH A HUGE AREA OF ABOVE NORMAL UPPER HEIGHTS EXTENDING FROM MEXICO UP TO SOUTHERN CANADA AND EAST THROUGH THE NORTHEASTERN US. THE TROUGH THAT WILL GIVE US A BIT OF INCLEMENT WEATHER EARLY...IS MADE TO CLOSE OFF UNDER THE RIDGE LEADING TO A NEARLY CLASSIC LOOKING REX BLOCK UPPER PATTERN BY MID TO LATE WEEK. BY WEDNESDAY...THE FIRST DAY OF FALL...AND LASTING INTO NEXT WEEKEND...I HAVE FAIR SKIES AND DAYTIME HIGHS GENERALLY IN THE 70S WITH LOW HUMIDITY. HIGHS WILL BE AVERAGING SOME 4-8 DEG ABOVE NORMAL. ASTRONOMICAL FALL STARTS AT 4:21 AM EDT ON SEPTEMBER 23. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... HIGH CLOUDS ACROSS MUCH OF THE AREA. REALLY BRIGHT ORANGE SUNRISE THIS MORNING. MOST AREAS WILL REMAIN DRY AND VFR TODAY AND TONIGHT. SOME SHOWERS...MORE LIGHT PATCHY RAIN AND DRIZZLE...WILL BE POSSIBLE ACROSS THE SOUTHERN PART OF CENTRAL PA TODAY AND TONIGHT. MVFR AND EVEN IFR CONDITIONS MAY BE POSSIBLE AT JST AND PERHAPS AT AOO LATER TODAY. MOST OF THE WEEK WILL FEATURE DRY CONDITIONS WITH VFR CONDITIONS...AS HIGH PRESSURE SFC AND ALOFT BUILDS ACROSS THE REGION. FORECAST DEWPOINTS NOT REAL HIGH TO SUPPORT MUCH IN THE WAY OF FOG FORMATION. OUTLOOK... TUE-FRI...MAINLY VFR. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LA CORTE AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
539 AM CDT MON SEP 21 2015 .AVIATION 12Z DISCUSSION... UPPER TROUGH AXIS WAS LOCATED JUST UPSTREAM THIS MORNING. THE WEAK UPPER LEVEL DYNAMICS MAY BE ENOUGH TO PRODUCE A FEW SHOWERS ACROSS SOUTHERN MIDDLE TN...BUT SHOULD NOT EFFECT THE TAF AREAS. OTW...THE AXIS WILL MOVE EAST OF THE MID STATE AND THEN INTENSIFY TONIGHT. AS A RESULT...DRIER AIR WILL WIN OUT THIS AFTERNOON AND ESPECIALLY ON TUESDAY. THEREFORE...THE TREND WILL BE TOWARD A DECREASE IN THE MID/UPPER LEVEL CLOUD COVER. SKC SHOULD PREVAIL AFT 00Z. && .PREV DISCUSSION... /ISSUED 443 AM CDT MON SEP 21 2015/ UPDATE... WITH WEAK UPPER LEVEL DISTURBANCE MOVING ACROSS SRN PORTIONS OF MID STATE AS OF 09Z(4AM CDT)...AND HRRR MODEL SHOWING THIS POSSIBILITY CONTINUING THRU 16Z(11 AM CDT)...WILL UPDATE THE SUITE OF FORECAST PRODUCTS TO MENTION A SLIGHT CHANCE TO CHANCE OF SHWRS ACROSS THESE AREAS THRU 16Z. SOME OF THE ABOVE MENTIONED RAINFALL MAY NOT BE ACTUALLY REACHING THE GROUND PER DRY AIR NOTED ACROSS THIS AREA GENERALLY BELOW 700MB PER MOST RECENT LAPS SOUNDING PROFILES. PREV DISCUSSION.../ISSUED 246 AM CDT MON SEP 21 2015/ SHORT TERM(TODAY-WED NIGHT)... FORECAST QUANDARIES...SKY COVER TIMING EROSION TODAY...TEMPS. A STRAIGHT FORWARD FORECASTS THRU WED NIGHT...WITH STRONG CONSENSUS BETWEEN MODEL SOLUTION RESOLUTIONS. HIGH PRESSURE INFLUENCES AND UPPER LEVEL RIDGING INFLUENCES BUILDING IN FROM THE MS RIVER VALLEY WILL BE THE MAIN WX PLAYERS ACROSS THE MID STATE THRU WED NIGHT. CLOUD COVERAGE APPROACHING 08Z WILL CONTINUE TO PUSH EWD AND OUT OF THE AREA AS THE DAY PROGRESSES...AS UPPER LEVEL TROUGHING INFLUENCES MOVE EWD AND ABOVE MENTIONED UPPER LEVEL RIDGING INFLUENCES BUILD ACROSS THE AREA. WILL THUS TAILOR CLOUD CONDITIONS TODAY FOR A DECREASING CLOUDINESS TREND W MID MORNING THRU EARLY AFTERNOON E. MOCLR SKIES ARE EXPECTED TONIGHT THRU WED NIGHT. SFC HIGH PRESSURE INFLUENCES WILL BUILD INTO THE MID STATE FROM THE SRN OHIO RIVER VALLEY TODAY BEFORE MERGING WITH HIGH PRESSURE INFLUENCES ACROSS THE NE U.S. AS FOR TEMPS...HIGH TEMPS TODAY WILL BE AROUND SEASONAL NORMAL VALUES... AROUND 80 TO LOWER 80S...MID TO UPPER 70S PLATEAU. TEMPS WILL WARM UP TO A FEW DEGREES ABOVE SEASONAL NORMAL VALUES...LOW TO MID 80S...UPPER 70S PLATEAU...BY WED AFTERNOON. LOWS WILL BE A FEW DEGREES BELOW SEASONAL NORMAL VALUES TONIGHT...MAINLY IN THE LOW TO MID 50S. LOWS ARE EXPECTED TO RISE MAINLY INTO THE UPPER 50S ACROSS THE AREA BY WED NIGHT. LONG TERM(THU-SUN)... THE GFS PROGRESSION OF THE EXT WEATHER PATTERN SEEMS TO BE A BIT MORE BELIEVABLE AS OPPOSED TO THE EURO SOLUTION. THE ORIENTATION OF THE UPPER RIDGE AXIS LOOKS A BIT UNORTHODOX AS IT STRETCHES FROM THE DESERT SOUTHWEST NORTHEASTWARD AND THE SOUTHEAST ACROSS THE MID ATLANTIC. MEANWHILE...THE GFS SOLUTIONS SHOWS A GENTLE RETROGRADE MOTION IN REGARD TO WEAK UPPER LEVEL TROUGHING OVER THE SOUTHEASTERN U.S. THEREFORE...IN THIS EXT FCST...WILL LEAN TOWARD THE GFS SOLUTION. ON THURSDAY...THE WEAK UPPER TROUGH WILL RESIDE ACROSS GA AND EASTERN TN. THIS WILL CONTINUE TO KEEP MIDDLE TN ON THE DRY SIDE IN THE MID AND UPPER LEVELS. IN THE LOWER LEVELS...A LARGE SFC HIGH OVER SOUTHERN PORTIONS OF THE HUDSON BAY WILL PROVIDE MAINLY AN EASTWARD COMPONENT IN THE LOWER LEVELS. THUS...THE OVERALL PATTERN WILL BE ON THE DRY SIDE. AS WE MOVE TOWARD THE WEEKEND...THE AFOREMENTIONED SFC HIGH WILL MOVE SOUTHEASTWARD AND REACH THE NEW ENGLAND AREA BY SUNDAY. AS A SOUTHWESTERN SFC RIDGE DEVELOPS TOWARD THE CAROLINAS...MORE OF A SOUTHERLY LOW LEVEL WIND COMPONENT WILL SET UP IN OUR NECK OF THE WOODS. IN THE UPPER LEVELS...THE UPPER LEVEL TROUGH WILL NOW BE LOCATED WEST OF THE MID STATE. THIS WILL PROVIDE A REBOUND OF MOISTURE IN THE MID AND UPPER LEVELS. SO FOR THE FCST...WILL BEGIN TO BRING BACK LOW CHANCES OF SHOWER ACTIVITY...MAINLY ACROSS EASTERN AREAS. THE EURO IS DRY THROUGHOUT THE PERIOD...SO EVEN THOUGH THATS NOT THE MODEL OF CHOICE...A BLEND AND A TREND TOWARD ISC GRIDS WILL KEEP POPS ON THE LOW SIDE FOR NOW. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 81 55 83 58 / 10 10 0 0 CLARKSVILLE 80 51 82 53 / 10 0 0 0 CROSSVILLE 74 52 77 55 / 10 10 0 0 COLUMBIA 81 51 83 54 / 40 10 0 0 LAWRENCEBURG 80 54 82 56 / 40 10 0 0 WAVERLY 81 53 83 54 / 10 0 0 0 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
645 AM CDT MON SEP 21 2015 .AVIATION... AS TEMPERATURES HAVE COOLED TO NEAR THE DEWPOINT WE HAVE SEEN AREAS OF LIGHT FOG AND LOW CLOUDS DEVELOP EARLY THIS MORNING. KLBB AND KPVW WILL LIKELY SEE A BRIEF BOUT OF MVFR CONDITIONS... THOUGH KCDS COULD FALL TO IFR OR EVEN LIFR FOR A SHORT WHILE. THE TERMINALS SHOULD RETURN TO VFR BY MID-MORNING WITH GOOD FLYING WEATHER EXPECTED FOR THE REMAINDER OF THE TAF CYCLE. WINDS WILL BE FAIRLY LIGHT AND GENERALLY OF A SOUTHERLY PERSUASION. && .PREV DISCUSSION... /ISSUED 349 AM CDT MON SEP 21 2015/ SHORT TERM... EARLY MORNING WATER VAPOR IMAGERY SHOWS THAT MUCH DRIER AIR ALOFT HAS INVADED THE SOUTH PLAINS REGION BEHIND YESTERDAY/S DISTURBANCE. THIS HAS BROUGHT A FIRM END TO PRECIPITATION CHANCES TODAY AS SHORTWAVE RIDGING BRIEFLY TRAVERSES WEST TEXAS. HOWEVER...SHALLOW MOISTURE DOES REMAIN AND WITH TEMPERATURES FALLING TOWARD THE DEWPOINT /DEPRESSIONS OF 1 TO 3 DEGREES ARE COMMON AT 08Z/ WE COULD SEE SOME LOW CLOUDS AND/OR FOG DEVELOP OVER THE NEXT FEW HOURS. THE SHALLOW NATURE OF THE MOISTURE AND THE VEERING /ALBEIT WEAK/ WIND COULD MITIGATE THE FOG POTENTIAL SOMEWHAT...THOUGH WE HAVE INCLUDED A PATCHY MENTION FOR MUCH OF THE CWA THROUGH MID-MORNING. ANY FOG AND LOW CLOUDS SHOULD QUICKLY MIX/SCATTER OUT WITH PLENTY OF SUN AND SOUTHERLY BREEZES PROPELLING TEMPERATURES BACK ABOVE AVERAGE. HIGHS ARE EXPECTED TO TOP OUT IN THE UPPER 80S AND LOWER 90S. TONIGHT WE WILL BEGIN TO SEE SOME MIDDLE AND UPPER LEVEL CLOUD COVER SPILL IN FROM THE WEST AS MOISTURE ASSOCIATED WITH TROPICAL DEPRESSION SIXTEEN-E SURGES NORTHEASTWARD INTO THE DESERT SOUTHWEST. ALTHOUGH THE BULK OF THE MOISTURE AND LIFT WILL BE DIRECTED TO OUR WEST WE COULD SEE A FEW SHOWERS EDGE TOWARD THE TX/NM LINE BY EARLY TUESDAY. OTHERWISE IT WILL BE A RATHER UNEVENTFUL AND MILD FALL NIGHT WITH LOWS MOSTLY IN THE 60S. LONG TERM... A UPPER-LEVEL STORM SYSTEM CURRENTLY LOCATED FROM WELL WEST OF THE BAJA PENINSULA AND THE REMNANT MOISTURE AND ENERGY FROM THE AFOREMENTIONED TROPICAL DEPRESSION WILL BE THE MAIN PLAYERS IN OUR WEATHER THIS WEEK. AS THE REMNANT WAVE MOVES NORTHEAST...SUB- TROPICAL MOISTURE WILL SPREAD OVER THE WESTERN SOUTH PLAINS ON TUESDAY RESULTING IN AN INCREASING CHANCE FOR SHOWERS AND THUNDERSTORMS FOR OUR COUNTIES NEAREST TO THE STATE LINE. THE HEAVY RAIN POTENTIAL IS EXPECTED TO LARGELY REMAIN TO OUR WEST AND NORTHWEST...BUT IT/S NOT OUT THE QUESTION THAT WE COULD SEE SOME TRAINING SHOWERS BRUSH PARMER COUNTY. THIS WAVE SHOULD HAVE PROGRESSED WELL NORTH OF THE AREA BY WEDNESDAY....BUT THE FOLLOWING WAVE SHOULD THEN BE APPROACHING FROM THE WEST. THIS WILL KEEP A CHANCE OF PRECIP GOING ACROSS OUR NORTHERN AND WESTERN COUNTIES THROUGH WEDNESDAY. STARTING THURSDAY...GUIDANCE IS STILL STRUGGLING WITH HOW THE STORM SYSTEM WILL EVOLVE ONCE IT MOVES EAST OF THE ROCKIES. BOTH THE GFS AND ECMWF SUGGEST SOME DEGREE OF TROUGHING FOR WEST TEXAS...BUT DIFFER ON THE DETAILS. THE ECMWF IS THE COOLER AND WETTER SOLUTION AS THE TROUGH ACTUALLY CLOSES OFF AT 500 MB THEN DRIFTS SOUTH AND WEAKENS OVER NORTHWEST TEXAS THURSDAY INTO FRIDAY. IN ADDITION...THE ECMWF SHOWS A COLD FRONT MOVING THROUGH THE AREA LATE THURSDAY WITH NORTH TO EAST LOW-LEVEL FLOW CONTINUING THROUGH THE WEEKEND. THE GFS IS WEAKER WITH THE FRONT...ALTHOUGH IT ALSO SHOWS SOME SURFACE RIDGING BUILDING INTO THE AREA. WITH THIS IN MIND...THE BLENDED GUIDANCE DOES PROVIDE POPS FOR ROUGHLY THE NORTHERN HALF OF THE FORECAST AREA THURSDAY INTO FRIDAY. TEMPERATURES SHOULD BE VERY NEAR SEASONAL NORMS THROUGH THE WEEK...NAMELY 80S FOR MOST LOCATIONS AND LOW 90S IN THE LOW ROLLING PLAINS. THE ECMWF PROJECTION WOULD SUPPORT COOLER TEMPERATURES LATE WEEK AND WE/LL BE FOLLOWING THE TRENDS IN THE MEDIUM-RANGE GUIDANCE. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 88 62 80 61 / 0 0 20 20 TULIA 88 63 85 63 / 0 0 0 10 PLAINVIEW 88 62 86 63 / 0 0 0 10 LEVELLAND 89 63 83 63 / 0 0 10 10 LUBBOCK 91 65 86 64 / 0 0 0 10 DENVER CITY 87 63 81 62 / 0 10 10 10 BROWNFIELD 89 64 83 63 / 0 0 10 10 CHILDRESS 92 68 93 68 / 0 0 0 0 SPUR 92 66 90 66 / 0 0 0 0 ASPERMONT 93 69 93 69 / 0 0 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 23/33/23
  [top] Area Forecast Discussion National Weather Service Midland/Odessa TX 629 AM CDT MON SEP 21 2015 .DISCUSSION... && .AVIATION... Western TAF sites have cleared out and radiated down to the dewpt allowing shallow fog to develop with LIFR vsbys and cigs. Do not expect this fog to last too long... also some patchy stratus across the Permian Basin and Trans Pecos hiding under the higher clouds. Have included evening storms at CNM. && .PREV DISCUSSION... /issued 408 AM CDT MON SEP 21 2015/ DISCUSSION...As of 4:00 AM CDT Monday...The main weather maker for the next couple of days will be EPAC TD 16-E which is moving across south central Baja California Sur. Southwesterly shear is displacing the thunderstorm activity into Sonora Mexico. Ridging is centered over West Texas/SE New Mexico. As the remnants of TD 16-E move into the Desert SW mid level moisture and instability will increase across the Davis and Guadalupe Mtns. Both the high resolution HRRR and RAP13 models and the mesoscale models indc convection possible over the Mtns thru mid week. The mid/upper level feature associated with this system will move NE through Northern New Mexico tonight/Tuesday with the ridge flattening. Have slight chc pops as far east as the Western Permian Basin tonight/Tuesday. With the moist ground from recent rains have trended temps a little below MOS guidance. Medium range models start to diverge mid week. The GFS is weaker and further north with the remnant mid/upper level shortwave... placing it in the Northern Plains by Thursday with broad ridging centered over the Desert SW. The ECMWF keeps a stronger mid/upper level shortwave further south with the ridge further west. The ECMWF is significantly wetter and cooler for the CWA...especially the Permian Basin and Trans Pecos Thursday thru Saturday. Will keep thunderstorm chances in the Mtns Wed/Thu...and the CWA dry Friday thru next weekend under weak ridging. Strobin && .MAF WATCHES/WARNINGS/ADVISORIES... NM...NONE. TX...NONE. && $$
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
144 PM PDT MON SEP 21 2015 .SYNOPSIS... WARM AND HUMID TODAY...WITH COOLER CONDITIONS TUESDAY. UPPER-LEVEL DISTURBANCES AND INCREASED MOISTURE WILL CREATE THE POSSIBILITY OF SHOWERS AND THUNDERSTORMS AT TIMES THIS AFTERNOON THROUGH TUESDAY AFTERNOON. DRY AND WARM FOR WEDNESDAY THROUGH SATURDAY AS HIGH PRESSURE ALOFT BUILDS OVER THE SOUTHWEST. SLIGHTLY COOLER SUNDAY INTO EARLY NEXT WEEK WITH A TROUGH OF LOW PRESSURE DEVELOPING ALONG THE WEST COAST. NIGHT AND MORNING MARINE LAYER CLOUDS POSSIBLY DEVELOPING ALONG THE COAST AND PORTIONS OF THE VALLEYS AT TIMES. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... AFTERNOON WATER VAPOR SATELLITE IMAGERY SHOWS A WEAKENING UPPER LOW ABOUT 440 MILES SOUTHWEST OF SAN DIEGO PRODUCING WITH WARMING CLOUD TOPS AND LESS LIGHTNING THAN THIS MORNING. SLOW MOVING BANDS OF ELEVATED SHOWERS AND THUNDERSTORMS OVER NORTHERN BAJA AND IMPERIAL COUNTY ASSOCIATED WITH A DEFORMATION AXIS HAVE MOSTLY STAYED TO THE SOUTH OF THE US/MEXICO BORDER...WITH JUST SOME SPRINKLES MAKING THEIR WAY INTO SAN DIEGO COUNTY. LATEST RADAR AND MODEL TRENDS INDICATE THAT THE HEAVIER SHOWERS ASSOCIATED WITH THIS BAND MAY NOT MAKE IT INTO SAN DIEGO COUNTY AFTERALL...AND SO SPRINKLES MAY BE ALL THAT MOST OF THE COUNTY WILL SEE THIS AFTERNOON...WITH THE ONLY OTHER CHANCE FOR RAIN THIS AFTERNOON FOR SAN DIEGO COUNTY AND AREAS FARTHER NORTH BEING FROM MOUNTAIN BASED CONVECTION. THE LATEST SPC MESOANALYSIS SHOWS PLENTY OF SURFACE BASED CAPE OVER THE REGION...WITH 1500 J/KG OF CAPE OVER THE EASTERN MOUNTAINS. HOWEVER...SURFACE BASED CONVECTION HAS YET TO DEVELOP...LIKELY DUE TO THE 150 TO 250 J/KG OF CONVECTIVE INHIBITION...OR CIN...WHICH THE SPC MESOANALYSIS SHOWS. NEVERTHELESS...THE HRRR STILL TRIES TO SHOW SOME THUNDERSTORMS GOING OFF OVER THE RIVERSIDE AND SAN DIEGO COUNTY MOUNTAINS LATER THIS AFTERNOON. THIS EVENING THROUGH TUESDAY AFTERNOON...THE LOW WILL WEAKEN AND MOVE INLAND THROUGH NORTHERN BAJA AND EXTREME SOUTHERN CALIFORNIA...WITH THE MODELS TRENDING FARTHER SOUTH WITH THE CORE OF THE LOW AS IT MOVES OVER EXTREME NORTHERN BAJA. WITH THE CORE OF THE LOW A LITTLE FURTHER SOUTH...THIS WOULD RESULT IN LESS CONFIDENCE FOR SHOWERS AND THUNDERSTORMS FOR NORTHERN AREAS SUCH AS ORANGE COUNTY...SAN BERNARDINO COUNTY AND THE INLAND EMPIRE. MODELS SHOW LESS MOISTURE...BUT THERE SHOULD STILL BE ENOUGH TO PRODUCE PRECIPITATION. IN ADDITION...THE NAM12 SHOWS SOME VORTICITY LOBES BEING DRAWN IN AROUND THE LOW AND BACK INTO THE RIVERSIDE AND SAN DIEGO COUNTY MOUNTAINS...LOWER DESERTS...AND WESTERN SAN DIEGO COUNTY...WHICH COULD INDUCE THUNDERSTORM AND SHOWER ACTIVITY IN THOSE AREAS DURING THE LATE NIGHT THROUGH TUESDAY MORNING PERIOD. THE 12Z LOCAL WRF AND 12Z CANSAC WRF HAVE BOTH PICKED UP ON THIS POSSIBILITY. STORM TOTAL RAINFALL AMOUNTS HAVE BEEN LOWERED DUE TO THE DECREASING FAVORABILITY OF HEAVY RAINFALL THAT THIS COMPLEX WEATHER PATTERN INDICATES. BASED ON LATEST MODEL GUIDANCE...SAN DIEGO COUNTY AND THE RIVERSIDE AND SAN DIEGO COUNTY MOUNTAINS AND LOWER DESERTS LOOK TO RECEIVE THE MOST AMOUNT OF RAINFALL...WITH LESS FOR AREAS NORTH. SEE THE HYDROLOGY SECTION BELOW FOR DETAILS ON THE FLASH FLOOD THREAT. AS FAR AS TEMPERATURES GO...TODAY IS SIGNIFICANTLY COOLER SO FAR THAN AT THIS TIME YESTERDAY...AS MOST LOCATIONS ARE SHOWING TEMPERATURES THAT ARE 10-20 DEGREES LOWER. THIS COOLING IS DUE TO INCREASING MOISTURE...CLOUDS AND TRENDING ONSHORE FLOW. COOLING WILL CONTINUE INTO TUESDAY WHEN DAY-TIME HIGHS COULD FALL TO NEAR TO BELOW NORMAL FOR INLAND AREAS...WHILE REMAINING A LITTLE ABOVE NORMAL AT THE COAST WITH THE CONTINUED WARM WATERS. ONE LAST INTERESTING TIDBIT ABOUT THE WEATHER TODAY ARE THE STRONG SOUTHERLY WINDS THAT HAVE DEVELOPED OVER THE COASTAL WATERS AND COASTAL LAND AREAS...WHICH MAY BE ASSOCIATED WITH THE LOW FAR TO THE SOUTHWEST. THOSE WINDS SHOULD DIMINISH THROUGH THE DAY...WITH ANOTHER ROUND OF GUSTY SOUTHERLY WINDS AT THE COAST TOMORROW INDICATED BY THE 12Z WRF. WEDNESDAY THROUGH SATURDAY...BENIGN DRY WEATHER PATTERN DEVELOPS...WITH RIDGING BUILDING AT 500 MB TO BRING A WARMING TREND. DAY-TIME HIGHS COULD REACH 5 TO 10 DEGREES ABOVE NORMAL ON FRIDAY AND SATURDAY. THE RIDGE STARTS TO WEAKEN SUNDAY INTO EARLY NEXT WEEK WITH A TROUGH MOVING INTO THE PACIFIC NORTHWEST. THIS SHOULD BRING SLOW COOLING TO THE REGION. && .AVIATION... 212030Z...TROPICAL LOW AND MID LEVEL MOISTURE IS OVER THE REGION WITH SOUTHWEST SURFACE WIND AHEAD OF A SURFACE AND UPPER LEVEL LOW REGION THAT IS 200 MILES SOUTHWEST OF SAN. THIS PRODUCED SCATTERED STRATOCU OVER LAND WITH A SOLID MID LEVEL DECK. THE MAIN UPPER LOW IS EXPECTED TO OPEN UP INTO A WAVE TONIGHT AND TUESDAY MORNING WHILE TRACKING JUST SOUTH OF THE MEXICO BORDER. THIS WILL ALSO DRAW IN ENERGY FROM THE EAST AND OUT OF ARIZONA...RESULTING IN SCATTERED SHOWERS AND THUNDERSTORMS MAINLY ALONG AND SOUTH FROM PSP TO SAN. THE BEST WINDOW FOR THIS ACTIVITY IS 09 TO 18Z TUESDAY. THE WAVE IS EAST OF SOUTHWEST CALIFORNIA BY TUESDAY AFTERNOON AND WILL DRAW SHOWERS WITH IT BUT LINGERING CONVECTION IS EXPECTED FOR PSP TO TRM INTO TUESDAY AFTERNOON WITHIN NORTHERLY STEERING FLOW. && .MARINE... 130 PM...ENHANCED SOUTHWEST FLOW AHEAD OF WEAKENING THUNDERSTORMS IN THE PACIFIC ASSOCIATED WITH A LOW PRESSURE WEATHER SYSTEM HAVE RESULTED IN GUSTS OF 20 KNOTS OVER WATERS. THE ENHANCED SOUTHERLY WIND CONTINUES INTO TUESDAY MORNING ALONG AND AHEAD OF THE LOW PRESSURE SYSTEM THAT MOVES EAST AND ENTERS THE CALIFORNIA BIGHT. THERE IS A CHANCE OF THUNDERSTORMS TODAY OVER THE WATERS AFTER 9 PM...AND CONTINUING THROUGH TUESDAY MORNING. BRIEF HEAVY RAIN AND GUSTY WINDS WITH SHOWERS. THE MARINE WEATHER STATEMENT CARRIES THE DETAILS...LAXMWSSGX. NO ADDITIONAL MARINE HAZARDS ARE EXPECTED THROUGH FRIDAY. && .BEACHES... 130 PM...THE THREAT OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS EXISTS LATE THIS EVENING THROUGH TUESDAY MORNING BEFORE DIMINISHING TUESDAY AFTERNOON. THE MAIN THREATS FROM ANY THUNDERSTORM THAT FORMS WILL BE LIGHTNING AND GUSTY ERRATIC WINDS WITH BRIEF HEAVY RAIN. THIS IS ASSOCIATED WITH THE STORMS SYSTEM SOUTHWEST OF SAN DIEGO WHICH TRACKS INTO NORTHERN MEXICO EARLY TUESDAY. && .HYDROLOGY... A FLASH FLOOD WATCH GOES INTO EFFECT CONTINUES THROUGH TUESDAY AFTERNOON FOR THE MOUNTAINS...LOWER DESERTS AND VALLEYS. WITH HIGH MOISTURE CONTENT...AN UNSTABLE ATMOSPHERE AND TWO UPPER LEVEL WAVES MOVING THROUGH THE AREA...THIS WILL LEAD TO THE POSSIBILITY OF HEAVY RAINFALL AND FLASH FLOODING. RAINFALL RATES COULD EXCEED 1 INCH PER HOUR...AND RECENT BURN SCARS COULD EXPERIENCE DEBRIS FLOWS. && .SKYWARN... SKYWARN ACTIVATION MAY BE NEEDED THIS AFTERNOON AND/OR EVENING FOR SAN DIEGO...RIVERSIDE AND SAN BERNARDINO COUNTIES. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...FLASH FLOOD WATCH THROUGH TUESDAY AFTERNOON FOR COACHELLA VALLEY- RIVERSIDE COUNTY MOUNTAINS-SAN BERNARDINO COUNTY MOUNTAINS- SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-SAN DIEGO COUNTY DESERTS-SAN DIEGO COUNTY MOUNTAINS- SAN DIEGO COUNTY VALLEYS-SAN GORGONIO PASS NEAR BANNING. PZ...NONE. && $$ PUBLIC...HARRISON AVIATION/MARINE/BEACHES...TARDY
AREA FORECAST DISCUSSION
NWS ALBANY NY
423 PM EDT MON SEP 21 2015 .SYNOPSIS... HIGH PRESSURE SITUATED OVER THE NORTHEAST WILL ALLOW FOR A DRY SEASONABLE AFTERNOON. HOWEVER SOME HIGH CLOUDS WILL PERSIST THROUGH EARLY TUESDAY DUE TO A DISTURBANCE WELL TO THE SOUTH. HIGH PRESSURE HOWEVER WILL REMAIN IN CONTROL INTO THE MUCH OF THE WEEK. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... AS OF 423 PM EDT...SUNSHINE WAS MIXED WITH HIGH CLOUDS ACROSS THE REGION. TEMPERATURES HAD REACHED THE LOWER 70S IN THE HUDSON VALLEY WELL SOUTH OF ALBANY...ONLY MID 60S CAPITAL REGION...60-65 MOST OTHER PLACES. A LIGHT NORTH WIND AVERAGE 5-10 MPH. SHOWERS IN PENNSYLVANIA WHERE ATTEMPTING TO MOVE NORTH INTO SOUTH CENTRAL NY STATE...BUT THUS FAR...HAS ENCOUNTERED VERY DRY AIR. THE LATEST HRRR DOES BRING SOME LIGHT SHOWERS ACROSS MUCH OF OUR REGION THIS EVENING (REALLY SPRINKLES) BUT FOR NOW WILL KEEP IT DRY ALL NIGHT...BUT SOME DEGREE OF CLOUD COVERAGE. THE SHOWERS WERE THE RESULT OF DEFORMATION BETWEEN A DISTURBANCE WELL TO OUR SOUTH AND AN INCOMING SHORT WAVE TO OUR NORTH. THE SOUTHERN FEATURE LOOKS TO STAY WELL SOUTH AND THE SHORT WAVE WILL MOVE ON BY TO OUR EAST LATER TUESDAY. THE CLOUDS LOOK TO HOLD TEMPERATURES UP A BIT COMPARED TO LAST NIGHT. THEREFORE...NO FROST IS EXPECTED ANYWHERE NOR ANY FOG. LOOK FOR LOWS RANGING FROM THE UPPER 30S ACROSS NORTHERN HERKIMER AND HAMILTON COUNTIES...LOWER TO MID 40S MOST OTHER PLACES...EXCEPT UPPER 40S TO AROUND 50 FROM THE CAPITAL REGION SOUTHWARD THROUGH THE HUDSON VALLEY. A NORTH TO NORTHEAST WIND THIS EVENING 5-10 MPH WILL BECOME LIGHT (UNDER 5 MPH) AND VARIABLE OVERNIGHT. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... TUESDAY WILL START WITH PLENTY OF CLOUDS...BUT AS AN AFOREMENTIONED SHORT WAVE MOVES BY...HIGH PRESSURE IS FORECAST TO BUILD BACK INTO THE REGION LATE TUESDAY AND PROVIDE DRY TRANQUIL WEATHER WITH SEASONABLE TEMPERATURES FOR THE REMAINDER OF THE SHORT TERM. LOOK FOR SEASONABLE TEMPERATURES WITH HIGHS 70-75 VALLEYS ...65-70 HIGHER TERRAIN. TUESDAY NIGHT WITH A MAINLY CLEAR SKY...TEMPERATURES WILL DIP BACK DOWN INTO THE UPPER 30S NORTHWEST TO MID 40S CAPITAL REGION SOUTHEAST. THERE WILL LIKELY BE PATCHY FOG. WEDNESDAY NIGHT WILL SEE LOWS SLIGHTLY HIGHER THAN TUESDAY NIGHT... GENERALLY LOWER 40S TO LOWER 50S. && .LONG TERM /THURSDAY THROUGH MONDAY/... THIS WILL BE A CONTINUATION OF A DRY PERIOD FROM START TO FINISH... WITH A WEAK COLD FRONT BREAKING DOWN THROUGH THE END OF THE WEEK...WITH A LARGE AREA BUILDING THROUGH THE WEEKEND FROM NORTHERN QUEBEC TO THE SOUTHEASTERN U.S. BY THE START OF THE WORK WEEK IT WILL STRETCH FROM THE MIDWEST ACROSS THE MID-ATLANTIC REGION...WITH NO SYSTEMS NEARBY. SKIES WILL BE MOSTLY CLEAR...THE ONLY EXCEPTIONS BEING FRIDAY IN THE VICINITY OF THE DIEING COLD FRONT...AND AGAIN SUNDAY NIGHT TOWARD AREAS OF HIGHER MID-LEVEL MOISTURE ADVECTION. WITH SATURDAY BEING THE ONLY EXCEPTION...DAYTIME TEMPERATURES WILL BE RUNNING AROUND 5 DEGREES ABOVE NORMAL. NIGHTTIME LOWS WILL AVERAGE RIGHT AROUND NORMAL...BUT PERHAPS ABOVE NORMAL IN THE HIGHER ELEVATIONS. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... VFR FLYING CONDITIONS EXPECTED THROUGH THE TAF PERIOD. HIGH CLOUDS PERSISTING INTO NIGHT SHOULD MITIGATE THE FORMATION OF FOG. HIGH PRESSURE CENTERED OVER THE REGION AT THE SURFACE AND IN THE LOWER LEVELS OF THE ATMOSPHERE WILL SHIFT OFF TO THE NORTHEAST TOWARD THE CANADIAN MARITIMES. WHILE ALOFT A SHORT WAVE CURRENTLY OVER THE OHIO VALLEY APPROACHES AND MOVES ACROSS THE EASTERN GREAT LAKES. THIS FEATURE WILL BRING HIGH AND MID LEVEL CLOUDS TO THE REGION...LOOKING AT VFR CONDITIONS THROUGH THE TAF PERIOD..12Z/TUESDAY. A LIGHT NORTH TO NORTHEAST FLOW WILL CONTINUE TODAY THE WIND WILL BECOME LIGHT AND VARIABLE TO CALM IN THE EVENING. OUTLOOK... TUE NIGHT-SATURDAY: ASIDE FROM SOME PATCHY EARLY MORNING FOG ...NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... LESS THAN A QUARTER INCH OF RAIN HAS FALLEN ACROSS MOST OF THE AREA IN THE PAST 8 DAYS. THE KEETCH-BYRAM DROUGHT INDEX (KBDI) WAS OVER 300 ACROSS THE MID HUDSON VALLEY INTO NORTHWEST CONNECTICUT... LOWER OVER THE REMAINDER NEW YORK AND ADJACENT WESTERN NEW ENGLAND. IT LOOKS TO CONTINUE TO BE DRY THROUGH AT LEAST THE BALANCE OF THE WEEK. TEMPERATURES WILL SEASONABLE. WITH THE EXCEPTION OF TONIGHT... A FULL RECOVERY IS EXPECTED WITH PLENTY OF DEW. TONIGHT...WE WILL HAVE A PARTIAL RECOVERY DUE TO HIGH CLOUDS KEEPING TEMPERATURES UP A LITTLE...A LITTLE HIGHER THAN THE DEWPOINTS. PARTIAL SUNSHINE IS EXPECTED TOMORROW...MORE SUNSHINE WEDNESDAY INTO THURSDAY. AFTERNOON RH VALUES WILL FALL TO THE MODERATE LEVELS (35-55 PERCENT) EACH OF THE NEXT SEVERAL AFTERNOONS. THE WIND WILL BE LIGHT AND VARIABLE DURING THE DAY (AROUND 5 MPH)...LIGHT TO CALM AT NIGHT. && .HYDROLOGY... NO HYDROLOGIC CONCERNS THROUGH THE NEXT FIVE DAYS. HIGH PRESSURE WILL ALLOW FOR DRY WEATHER THROUGH THE ENTIRE WEEK. THE ONLY EXCEPTIONS MIGHT BE A FEW SPRINKLES SOUTH TONIGHT AND PERHAPS AGAIN ON FRIDAY. OTHERWISE...NO PRECIPITATION IS EXPECTED AT ALL OVER THE REGION THROUGH AT LEAST FRIDAY. STREAMFLOW LEVELS OVER EASTERN NY AND WESTERN NEW ENGLAND COMPARED TO HISTORICAL NORMALS ARE GENERALLY NEAR AVERAGE IN MOST LOCATIONS...WITH A FEW SPOTS COMING IN AT BELOW NORMAL LEVELS. WITH DRY WEATHER EXPECTED OVER THE NEXT WEEK...RIVER LEVELS WILL CONTINUE TO REMAIN NEARLY STEADY OR SLOWLY FALL. A FEW MORE SPOTS MAY BE COMING IN BELOW NORMAL BY THIS TIME NEXT WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...HWJIV NEAR TERM...HWJIV SHORT TERM...HWJIV LONG TERM...ELH AVIATION...HWJIV FIRE WEATHER...HWJIV HYDROLOGY...FRUGIS/HWJIV
AREA FORECAST DISCUSSION
NWS NEW YORK NY
345 PM EDT MON SEP 21 2015 .SYNOPSIS... HIGH PRESSURE GRADUALLY RETREATS TO THE NORTHEAST THROUGH TUESDAY. ANOTHER HIGH BUILDS IN FROM SOUTH CENTRAL CANADA TUESDAY NIGHT INTO WEDNESDAY NIGHT. A COLD FRONT APPROACHING FROM THE NORTH ON THURSDAY WILL DISSIPATE OVER THE AREA ON FRIDAY...FOLLOWED BY STRONG HIGH PRESSURE BUILDING SOUTH FROM HUDSON BAY OVER THE WEEKEND INTO NEXT MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... DEEP LAYERED RIDGE AXIS LIFTS TO THE NORTHEAST THIS EVENING...WITH A WEAK 700-500 HPA SHORTWAVE PUSHING THROUGH IN ITS WAKE. COULD SEE ENOUGH FORCING AHEAD OF THE SHORTWAVE TO PRODUCE SOME ISOLATED SHOWERS OVER MAINLY FAR W ZONES THIS EVENING...SO HAVE SLIGHT CHANCE POPS OVER ORANGE AND WESTERN PASSAIC COUNTY. SOME SIGNS IN LATEST HRRR AND RADAR TRENDS THAT THIS MIGHT NEED TO BE NUDGED A TAD FARTHER EAST...BUT THIS IS A NEW DEVELOPMENT...SO WILL HOLD OFF ON THAT FOR NOW. IT WILL BE CLOUDY TONIGHT...WITH MID TO HIGH CLOUDS CONTINUING TO BUILD IN FROM THE SW THROUGHOUT HE NIGHT...AND LOW CLOUDS BUILDING IN FROM SE TO NW FROM OFFSHORE MAINLY AFTER MIDNIGHT. FOR LOWS TONIGHT USED A BLEND OF MAV/MET/ECS GUIDANCE AND NAM 2-METER TEMPERATURES...WITH VALUES FORECAST TO BE A FEW DEGREES ABOVE NORMAL. PERSISTENT NE-ENE FLOW OF 15-20KT CREATING A STRONG LONGSHORE CURRENT...SO WILL CONTINUE WITH A HIGH RISK OF RIP CURRENTS FOR EASTERN ATLANTIC BEACHES TONIGHT...AND A MODERATE RISK OF RIP CURRENT FOR CENTRAL AND WESTERN ATLANTIC BEACHES. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/... A WEAK 700-500 HPA NORTHERN STREAM TROUGH MOVES THROUGH TUESDAY...FOLLOWED BY DEEP LAYERED RIDGING BUILDING IN FROM THE WEST TUESDAY NIGHT. WHILE A SPRINKLE OR TWO CANNOT BE RULED OUT TUESDAY WITH THE PASSAGE OF THE TROUGH...GIVEN VERY DRY LOW LEVELS...DO NOT HAVE CONFIDENCE TO PLACE IN THE FORECAST. HOWEVER...DO EXPECT AT BEST MOSTLY CLOUDY SKY CONDITIONS FOR MOST...IF NOT ALL THE DAY. THE CLOUDS WILL KEEP TEMPERATURES DOWN...WITH HIGHS WITHIN A COUPLE DEGREES OF EITHER SIDE OF NORMAL. THIS IS CONSISTENT WITH A BLEND OF MIXING DOWN FROM 900 HPA PER BUFKIT SOUNDINGS...WITH NAM 2-METER TEMPERATURES AND A BLEND OF MAV/ECS/MET GUIDANCE. SHOULD SEE CLEARING TUESDAY NIGHT FROM W TO E AS THE DEEP LAYERED RIDGE BUILDS IN. FOR LOWS A BLEND OF MAV/MET/ECS GUIDANCE AND NAM 2-METER TEMPERATURES. LOWS SHOULD BE SLIGHTLY ABOVE NORMAL. THE PERSISTENT ENE-NE FLOW WILL CAUSE THE LONGSHORE CURRENT TO PERSIST AND STRENGTHEN FARTHER TO THE WEST. AS A RESULT...HAVE A HIGH RISK OF RIP CURRENTS FORECAST FOR ALL ATLANTIC BEACHES FROM TUESDAY INTO TUESDAY EVENING. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... SFC HIGH PRESSURE OVER THE AREA WILL WEAKEN...WHILE A MID LEVEL SHORTWAVE TROUGH PASSES TO THE SOUTH AND EAST...AND AS THE PATTERN OVER NORTH AMERICA BECOMES MORE AMPLIFIED...WITH A BUILDING RIDGE OVER THE CENTRAL STATES...AND A DOWNSTREAM DIGGING TROUGH OVER EASTERN CANADA...WITH HEIGHTS FALLING OVER THE LOCAL AREA. THIS WILL ALSO SERVE TO SUPPRESS AN UPPER LOW OVER THE SOUTHEAST STATES AND AN ASSOCIATED OFFSHORE WEAK LOW OR INVERTED TROUGH...THIS PER THE 00Z/12Z ECMWF...00Z ECMWF ENSMEAN AND ALSO THE 12Z GEFS MEAN...AT LEAST THROUGH THE WEEKEND. A BACK DOOR COLD FRONT ASSOCIATED WITH THE DIGGING TROUGH WILL APPROACH ON THU...THEN WASH OUT OVER THE AREA ON FRI. AFTER A STRONG DIGGING SHORTWAVE EMBEDDED IN THE NORTHERN STREAM TROUGH PASSES TO THE NE FRI NIGHT...STRONG SFC HIGH PRESSURE WILL BUILD SOUTH FROM NEAR HUDSON BAY AND BECOME DOMINANT...AT LEAST THROUGH THE WEEKEND. THEREAFTER...THE FORECAST OF MOSTLY SUNNY DRY WEATHER ON MON IS UNCERTAIN,,,ESPECIALLY FOR NYC METRO AND COASTAL SECTIONS...AS BOTH THE 12Z ECMWF AND GEFS MEAN START TO BRING THE LOW OR INVERTED TROUGH TO OUR SOUTH UP THE COAST. TEMPS WILL RUN SEVERAL DEG ABOVE AVG WED-FRI...MAINLY 75-80...THEN WILL TREND BACK CLOSER TO AVG THIS WEEKEND INTO EARLY NEXT WEEK. && .AVIATION /19Z MONDAY THROUGH SATURDAY/... HIGH PRESSURE REMAINS OVER THE REGION. VFR INTO THIS EVENING. WINDS NE-ENE AROUND 10 KT WITH GUSTS UP TO 15-19KT...DIMINISHING BY A FEW KTS THIS EVENING. NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: END TIME OF FREQUENT GUSTS COULD BE OFF BY 1-2 HOURS. KLGA FCSTER COMMENTS: END TIME OF FREQUENT GUSTS COULD BE OFF BY 1-2 HOURS. KEWR FCSTER COMMENTS: END TIME OF FREQUENT GUSTS COULD BE OFF BY 1-2 HOURS. KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED. KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED. KISP FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED. .OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY... .TUE-FRI...VFR WITH CONTINUED NE-ENE FLOW. GUSTS TO 20 KT POSSIBLE EACH DAY. && .MARINE... PERSISTENT NE-ENE FLOW WILL KEEP SEAS ABOVE SCA LEVELS THROUGH AT LEAST TUESDAY NIGHT. GUSTS TO 25 KT EXPECTED ON THE COASTAL OCEAN WATERS INTO TUESDAY NIGHT AS WELL. COULD ALSO SEE SOME OCCASIONAL GUSTS TO 25 KT ON THE NON-OCEAN WATERS TONIGHT...WITH GUSTS UP TO 20 KT TUESDAY INTO TUESDAY NIGHT. WINDS SHOULD DIMINISH SOMEWHAT ON ALL WATERS DURING TUESDAY NIGHT...AS THE PRESSURE GRADIENT BRIEFLY RELAXES. SCA CONDITIONS IN THE FORM OF HAZARDOUS SEAS SHOULD CONTINUE ON THE OCEAN INTO WED. AS SFC HIGH PRESSURE WEAKENS...A RELATIVE RESPITE IN SCA CONDITIONS SHOULD OCCUR WED NIGHT...AND MAY LAST INTO FRI EVENING...THOUGH COULD BE INTERRUPTED AT TIMES BY SETS OF HIGHER SWELLS MOVING IN FROM THE SOUTH. SCA CONDITIONS LIKELY TO RETURN ON THE OCEAN LATE FRI NIGHT INTO SAT AS STRONG HIGH PRESSURE STARTS TO BUILD FROM THE NORTH AND TIGHTENS THE PRESSURE GRADIENT. && .FIRE WEATHER... DRY CONDITIONS. CURRENTLY KBDI VALUES ARE GREATER THAN 300 OVER A GOOD PORTION OF THE REGION...AND OVER 400 ALONG THE COAST. NE WINDS GUSTING 15-20 MPH WITH RH VALUES IN THE MID 40S TUESDAY ACROSS THE INTERIOR...THERE COULD BE SOME RISK OF FIRE SPREAD...IF ANY WERE TO BE IGNITED. && .HYDROLOGY... MAINLY DRY TONIGHT...THEN DRY INTO THE WEEKEND. && .TIDES/COASTAL FLOODING... A PERSISTENT E TO W SWEEP OF 3 TO 6 FT BREAKERS AND ELEVATED TIDES WILL RESULT IN SOME MINOR BEACH EROSION THIS WEEK ON THE SOUTH SHORE OF LONG ISLAND. A LOW THREAT OF MINOR COASTAL FLOODING EXISTS LATE THIS WEEK INTO THE WEEKEND WITH GRADUALLY RISING ASTRONOMICAL HIGH TIDES AND POTENTIAL FOR STRENGTHENING OF EASTERLY FLOW. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...HIGH RIP CURRENT RISK FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR NYZ075-080-178-179. HIGH RIP CURRENT RISK THROUGH TUESDAY EVENING FOR NYZ081. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ350-353- 355. && $$ SYNOPSIS...MALOIT/GOODMAN NEAR TERM...MALOIT SHORT TERM...MALOIT LONG TERM...GOODMAN AVIATION...JC MARINE...MALOIT/GOODMAN FIRE WEATHER...MALOIT HYDROLOGY...MALOIT/GOODMAN TIDES/COASTAL FLOODING...MALOIT/GOODMAN
AREA FORECAST DISCUSSION
NWS MIAMI FL
127 PM EDT MON SEP 21 2015 .AVIATION... SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP THIS AFTERNOON. SOME OF THEM COULD IMPACT ALL TAF SITES THROUGH THE EVENING HOURS. THEY CAN BRING BRIEF PERIODS OF IFR CONDITIONS. THE SHORT RANGE HRRR MODEL INDICATED THESE SHOWERS AND STORMS WILL CONTINUE TO DEVELOP INTO THE EVENING HOURS. CURRENTLY HAVE MOST CONVECTION FORECAST TO WIND DOWN AROUND O1Z, HOWEVER, THERE IS POTENTIAL THAT IT COULD PERSIST SOMEWHAT LONGER INTO THE NIGHT. && .PREV DISCUSSION... /ISSUED 1007 AM EDT MON SEP 21 2015/ UPDATE... NO SIGNIFICANT UPDATES WITH THIS UPDATE. ONLY MINOR TWEAKS TO THE NEAR TERM ELEMENTS TO ACCOUNT FOR CURRENT CONDITIONS. PREV DISCUSSION... /ISSUED 750 AM EDT MON SEP 21 2015/ UPDATE... UPDATED THE FORECAST THIS MORNING TO REFLECT THE DEVELOPMENT OF FOG IN THE INTERIOR THIS MORNING, BESIDES MINOR TWEAKS TO OTHER ELEMENTS OF THE FORECAST. AN AREA OF MOISTURE IS MOVING INTO THE AREA THIS MORNING, AND SHOULD PASS ACROSS THE CWA BY EARLY AFTERNOON. AVIATION... MAINLY VFR CONDITIONS ALONG THE COASTAL AREAS. THERE IS A SLIGHT CHANCE OF THUNDERSTORMS, BUT MOST OF THE ACTIVITY WILL BE INLAND. BUT, ISOLATED STORMS HAVE THE POTENTIAL TO AFFECT THE COASTAL TAF SITES THIS AFTERNOON. THEREFORE, KEPT THE VCTS AT MOST OF THE TAF SITES THIS AFTERNOON. PREV DISCUSSION... /ISSUED 336 AM EDT MON SEP 21 2015/ DISCUSSION... TODAY-TONIGHT...NOT MUCH CHANGE IN THE OVERALL PATTERN FROM SUNDAY AS A BROAD SURFACE LOW CONTINUES TO SPIN OFF THE CAROLINA COAST WITH ITS TRAILING TROUGH LINGERING ACROSS FAR SOUTH FL/FL STRAITS THIS MORNING. NORTH-NORTHEASTERLY FLOW AROUND THE LOW WILL CONTINUE TO BRING DRIER AIR INTO SOUTH FLORIDA...ESPECIALLY AROUND LAKE OKEECHOBEE AND PALM BEACH COUNTY. WITH THE DRY MID LEVEL AND WEAK CAP...EXPECT ANOTHER SLOW START TO ACTIVITY. WIDELY SCATTERED SHOWERS AND STORMS DEVELOPING ALONG THE EAST COAST SEA BREEZE WILL TREND INLAND INTO THE LATE AFTERNOON...WITH THE BEST RAIN CHANCES...AROUND 50%...SOUTH OF ALLIGATOR ALLEY OVER THE EVERGLADES TOWARDS SUNSET. DEWPOINTS EXPECTED TO DROP INTO THE UPPER 60S AROUND THE LAKE AND LOW 70S FOR THE REST OF THE REGION WHICH IS SLIGHTLY...BUT LIKELY NOTICEABLY...LOWER THAN THE USUAL MID-UPPER 70S FOR THIS TIME OF YEAR. TUESDAY...MID LEVEL TROUGH SWINGS SWINGS INTO THE SOUTHEASTERN US DURING THE DAY ON TUESDAY AS THE FL PENINSULA REMAINS IN LIGHT LOW LEVEL EAST-NORTHEAST FLOW BETWEEN THE LARGE HIGH OVER THE NORTHEASTERN US AND LINGERING SURFACE LOW/TROUGH OVER THE WESTERN ATLANTIC. A DRIER AIR MASS REMAINS IN PLACE BOTH AT THE SURFACE AND MID LEVELS AND WILL CONTINUE TO KEEP AFTERNOON STORM COVERAGE LOW AND LATE IN THE DAY WITH THE SEA BREEZE. WITH NORTHERLY COMPONENT TO THE STEERING FLOW...BEST RAIN CHANCES WILL CONTINUE OVER THE FAR SOUTHERN PORTIONS OF THE PENINSULA IN MIAMI-DADE AND MAINLAND MONROE. AS WITH MONDAY...SLIGHTLY LOWER DEWPOINTS WILL CONTINUE TO BRING A SUBTLE RELIEF TO THE USUAL S FLORIDA HUMIDITY. WEDNESDAY-SATURDAY...NOT MUCH CHANGE IN THE OVERALL FORECAST MID TO LATE WEEK AS GLOBAL MODELS STILL SHOW THE TROUGH MOVING INTO THE EASTERN US CUTTING OFF OVER THE SOUTHEAST. STILL RUN TO RUN AND MODEL TO MODEL DIFFERENCES IN THE PLACEMENT OF THE CUT OFF LOW WITH THE GFS BACK ON BOARD WITH A MORE ROBUST RETROGRADING CUT OFF LOW THOUGH THE ECMWF HAS NOW TRENDED WEAKER WITH THE FEATURE. TRENDS FROM BOTH MODELS STILL SUGGEST A WETTER AND STORMIER PATTERN IN PLACE BY LATE WEEK WITH LOWER SURFACE PRESSURES AND MID LEVEL HEIGHTS AS WELL A DEEPER SOUTHERLY FLOW USHERING IN SOME BETTER MID LEVEL MOISTURE ADVECTION. HOW MUCH WE GET CONTINUES TO VARY...BUT WILL KEEP INCREASING POP TREND THURS-SAT. MARINE...NORTH-NORTHEAST WINDS AROUND 10KTS THROUGH MID WEEK BECOMING EAST-SOUTHEAST 5-10KTS LATE WEEK. GULF COAST BREEZE EXPECTED MOST DAYS...WHICH WILL BRING WINDS TO THE WEST-NORTHWEST NEAR THE COAST IN THE AFTERNOONS. SEAS GENERALLY 2FT OR LESS THROUGH WED...WITH UP TO 4FT IN THE GULF STREAM AT TIMES WITH THE NORTHEAST FETCH. SEAS GRADUALLY INCREASE IN THE ATLANTIC MID TO LATE WEEK WITH INCOMING SWELL. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 74 89 75 88 / 10 20 20 30 FORT LAUDERDALE 77 88 76 88 / 20 30 20 30 MIAMI 77 89 76 89 / 20 30 20 30 NAPLES 75 90 72 88 / 20 20 20 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...13/SI LONG TERM....88/ALM AVIATION...13/SI
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
116 PM CDT MON SEP 21 2015 .AVIATION... ISOLATED TO POSSIBLY SCATTERED SHRA/TSRA COULD STILL REDEVELOP AND POSSIBLY BRIEFLY IMPACT AN AIRPORT OR TWO THROUGH THIS AFTERNOON...HOWEVER THE CONFIDENCE IS NOT HIGH ENOUGH TO INCLUDE MENTION IN THE TAFS. VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH TUESDAY WITH MOSTLY MID AND HIGH LEVEL CLOUDS AND NO SIGNIFICANT VSBY REDUCTIONS ANTICIPATED. 22/TD && .PREV DISCUSSION... /ISSUED 1055 AM CDT MON SEP 21 2015/ UPDATE... SATELLITE TRENDS INDICATE THAT THE OVERCAST SKIES WILL LINGER OVER THE AREA THROUGH MUCH OF THE DAY. THERE WILL ALSO BE CONTINUED RAIN SHOWERS THROUGH THE AFTERNOON...WITH COVERAGE EXPECTED TO INCREASE OVER THE SOUTHERN HALF OF THE FORECAST AREA DURING THE AFTERNOON HOURS. HAVE BUMPED UP POPS FOR THE SOUTHERN PART OF THE CWA TO HIGH END CHANCE TO REFLECT THIS RISK. TEMPERATURES TRENDS ARE COOLER THAN EXPECTED GIVEN THE PERSISTENT CLOUD COVER...WITH READINGS ACROSS THE NORTHERN HALF OF THE FORECAST AREA A GOOD 5 DEGREES COOLER THAN EXPECTED. WITH CLOUD COVER EXPECTED TO LINGER THROUGH THE AFTERNOON HOURS...HAVE LOWERED HIGHS FOR THE DAY BY A FEW DEGREES ON AVERAGE. HIGHS SHOULD ONLY PEAK IN THE LOWER TO MIDDLE 80S OVER MUCH OF THE AREA THIS AFTERNOON. 32 PREV DISCUSSION... /ISSUED 912 AM CDT MON SEP 21 2015/ UPDATE... UPDATED RAIN CHANCES TO SHOW A GRADIENT FROM 100 PERCENT NORTH TO 25 TO 30 PERCENT SOUTH TO BLEND WITH CURRENT RADAR TRENDS AND LATEST HRRR RUNS THIS MORNING. DRIER AIR BEHIND COLD FRONT WILL START TO DIMINISH RAIN COVERAGE IN THE FAR NORTH/NORTHWEST LATE THIS MORNING...SO TAPER TRENDS BACK TO THE ORIGINAL MORNING FORECAST. REMAINDER OF FORECAST LOOKS GOOD AT THIS TIME. 22/TD PREV DISCUSSION... /ISSUED 252 AM CDT MON SEP 21 2015/ SHORT TERM... SHOWERS AND A FEW TS WILL BE POSSIBLE TODAY AS AN 850MB TROUGH MOVES THROUGH. THE SFC COLD FRONT WILL MOVE THROUGH TUESDAY MORNING AS THE AIR MASS DRIES VIA DP TEMPS FALLING BACK INTO THE 50S. BUT THIS SHOULD BE SHORT LIVED AS DEEPER MOISTURE WILL MOVE IN FROM THE EAST BY WED EVENING. THE DEEP MOISTURE WILL NOT MAKE A LOT OF HEADWAY THOUGH AND GETS HELD NEAR THE LOWER PEARL RIVER. A NEW SURGE OF DRY AIR MOVES BACK INTO THE AREA TO KEEP THE DEEPER MOISTURE OFFSHORE BY THURSDAY EVENING. LONG TERM... THE WEEKEND LOOKS TO BE DRY FOR THE MOMENT AND WITH DP TEMPS BACK INTO THE MID 50S...AMBIENT TEMPS MAY MAKE THINGS FEEL NICE OR COOL TO SOME. DEEP MOISTURE ONCE AGAIN WILL MOVE IN FROM THE EAST BY THE START OF NEXT WEEK BRINGING THE SHOWER ACTIVITY BACK WITH IT. ANOTHER DEEP UPPER TROUGH WILL BE DIGGING INTO THE GULF BY NEXT WEEK SO WE WILL HAVE TO SEE EXACTLY WHERE THE SFC FRONT SETS UP OVER THE DEEP SOUTH. AVIATION...A WEAK FRONTAL BOUNDARY CONTINUE TO SLOWLY PUSH SOUTH ACROSS THE AREA THIS MORNING...AND WILL CONTINUE TO DO SO BEFORE CLEARING THE COAST AND EVENTUALLY BECOMING DIFFUSE. MAINLY MID AND UPPER LEVEL CLOUDS ARE BEING OBSERVED ACROSS THE REGION IN ADVANCE OF A SHORTWAVE TROUGH. A FEW POST FRONTAL SHRA WERE ALSO BEING OBSERVED BUT ALL WERE STILL OUT OF THE CWA. VFR CONDITIONS WILL GENERALLY PREVAIL AT THE TERMINALS THROUGH THE TAF FORECAST PERIOD BUT CANT RULE OUT TEMPO MVFR DUE TO SHRA. /CAB/ MARINE...THE WEAK FRONT IS SLOWLY MOVING SOUTH THROUGH THE CWA AND HAS ALREADY APPROACHED THE MS COAST AND SHOULD ENTER ALL OF THE COASTAL WATERS LATE THIS MORNING. WINDS WILL VEER AROUND TO OFFSHORE AND COULD RANGE FROM 10-13KTS AT TIMES BUT WITH THE LACK OF ANY REAL SIGNIFICANT CAA NOT EXPECTING STRONG WINDS. THE FRONT WILL WASHOUT QUICKLY BASICALLY LEAVING THE AREA B/T BROAD LOW PRESSURE IN THE SRN GULF AND BROAD HIGH PRESSURE DOMINATING MUCH OF THE ERN CONUS. THIS WILL LEAD TO PERSIST MODERATE ERLY WINDS THROUGH MUCH OF THE WEAK. MDLS ARE CONTINUING TO INDICATE THE POSSIBILITY OF A WEAK SFC LOW DEVELOPING NEAR THE YUCATAN LATE NEXT WEEKEND...SO WILL NEED TO CONTINUE TO WATCH THIS POSSIBLE DEVELOPMENT. /CAB/ && DECISION SUPPORT... DSS CODE....GREEN. DEPLOYED...NONE. ACTIVATION...NONE. ACTIVITIES...NONE. DECISION SUPPORT SERVICES (DSS) CODE LEGEND GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH VISIBILITY EVENT YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES RED = FULL ENGAGEMENT FOR MODERATE RISK SVR AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE && .PRELIMINARY POINT TEMPS/POPS... MCB 85 65 88 65 / 100 10 0 0 BTR 86 68 90 67 / 50 10 0 0 ASD 84 68 89 70 / 60 20 0 0 MSY 85 72 88 73 / 30 20 0 0 GPT 83 69 89 71 / 60 20 0 0 PQL 84 67 89 70 / 60 20 0 0 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...NONE. GM...NONE. MS...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
120 PM EDT MON SEP 21 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 507 AM EDT MON SEP 21 2015 WV IMAGERY AND RAP ANALYSIS INDICATED ZONAL MID/UPPER LEVEL FLOW FROM THE PAC NW INTO NRN ONTARIO AND A WEAK TROUGH OVER THE GREAT LAKES. A VIGOROUS SHRTWV TROUGH WAS MOVING THROUGH SRN ALBERTA. AT THE SFC...INCREASING SRLY FLOW PREVAILED ACROSS THE UPPER MS VALLEY INTO THE WRN LAKES BETWEEN HIGH PRES OVER NEW ENGLAND AND A TROUGH EXTENDING INTO THE PLAINS FROM LOW PRES OVER SRN SASK/MANITOBA. THE WAA PATTERN SUPPORTED ONLY PATCHY MID CLOUDS FROM WRN LAKE SUPERIOR THROUGH WI. TODAY...ABUNDANT SUNSHINE AND MIXING THROUGH 850 MB TEMPS CLIMBING INTO THE 10C-12C RANGE WILL SUPPORT MAX TEMPS IN THE LOW TO MID 70S. SLIGHTLY WARMER CONDITIONS WILL AGAIN PREVAIL IN DOWNSLOPE FLOW LOCATIONS ALONG LAKE SUPERIOR. FCST WINDS THROUGH THE MIDDLE AND UPPER PORTION OF THE MIXED LAYER SUPPORT WIND GUSTS INTO THE 20-25 MPH RANGE WITH SOME 25-30 MPH GUSTS OVER THE WEST. TONIGHT...AS THE VIGOROUS SHRTWV TROUGH AND ASSOCIATED DEEP SFC LOW LIFTS FROM NRN MANITOBA TO HUDSON BAY A COLD FRONT WILL BE DRAGGED THROUGH THE NRN LAKES. GIVEN THE ABSENCE OF DEEP MOISTURE...ONLY MODEST MOISTURE TRANSPORT ALONG THE FRONT AS WELL AS THE STRONGEST MID LEVEL FORCING REMAINING WELL TO THE N OVER NRN ONTARIO (SLIGHT HEIGHT RISES ARE FCST OVER THE NRN LAKES TONIGHT)...WILL CONTINUE TO MENTION ONLY LOWER END CHANCE POPS FOR SHRA/TSRA OVER NORTHWEST HALF LATE TONIGHT. MUCAPE VALUES INTO THE 500-1000 J/KG RANGE WILL SUPPORT TSRA CHANCES BUT WILL BE MARGINAL FOR THE POTENTIAL OF ANY STRONGER STORMS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 346 AM EDT MON SEP 21 2015 LIMITED CHANGES IN THE OVERALL LONG TERM FORECAST FROM 24 HOURS AGO...AS THE UPPER JET TRACKS FROM WEST TO EAST ACROSS SOUTHERN CANADA THROUGH THE LATER PART OF THIS WEEK BEFORE AMPLIFYING OVER CENTRAL CANADA FOR NEXT WEEKEND. THAT LOCATION OF THE JET WILL KEEP THE NORMAL (MIDDLE OF THIS WEEK) TO ABOVE NORMAL TEMPERATURES (THIS WEEKEND) IN PLACE THROUGHOUT THE FORECAST PERIOD. THERE ARE TWO OPPORTUNITIES FOR RAIN DURING THIS FORECAST PERIOD...WITH THE FIRST TIED TO THE COLD FRONT DROPPING SOUTHEAST ACROSS THE AREA ON TUESDAY MORNING. THE COMBINATION OF LIMITED MOISTURE AND UPPER LEVEL SUPPORT SHOULD ONLY LEAD TO ISOLATED SHOWERS DROPPING SOUTHEAST ACROSS THE CENTRAL/EASTERN U.P. AS THE FRONT MOVES THROUGH THAT AREA ON TUESDAY. DID CONTINUE TO MENTION A SLIGHT CHANCE OF THUNDER DUE TO THE THIN REGION OF WEAK INSTABILITY AHEAD OF THE FRONT. CANADIAN HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND THE FRONT AND SHOULD LEAD TO MOSTLY CLEAR SKIES OVER THE WESTERN U.P. TUESDAY AFTERNOON AND THE REST OF THE AREA ON TUESDAY NIGHT. THE NEXT OPPORTUNITY FOR RAIN WILL COME FROM BROAD WARM AIR ADVECTION DEVELOPING ON TUESDAY NIGHT IN THE MID-UPPER MISSISSIPPI VALLEY THAT WILL LIFT NORTH-NORTHEAST INTO THE WESTERN CWA ON WEDNESDAY. THERE SHOULD BE PLENTY OF MOISTURE TO WORK WITH THIS AS EXISTING MOISTURE IN THE PLAINS COMBINES WITH THE REMNANTS OF TROPICAL DEPRESSION SIXTEEN-E CURRENTLY NEAR THE BAJA PENINSULA. THE LATEST TRENDS IN THE MODELS KEEPS MUCH OF THE ENERGY FROM THE TROPICAL REMNANTS IN THE CENTRAL PLAINS...SO THE PRECIPITATION WILL BE TIED TO THAT INITIAL SURGE OF WARM AIR ADVECTION ON WEDNESDAY INTO WEDNESDAY NIGHT. THAT SURGE WILL BE OVER NORTHEAST MINNESOTA INTO NORTHWEST WISCONSIN ON WEDNESDAY MORNING AND THEN SLIDE EAST INTO WESTERN LAKE SUPERIOR AND THE WESTERN U.P. THROUGH THE DAY ON WEDNESDAY. WILL FOCUS THE HIGHEST POPS IN THAT AREA AND THEN SLOWLY DIMINISH THEM AS THE FORCING WEAKENS AND MOVES EAST ACROSS THE REST OF THE CWA WEDNESDAY NIGHT INTO THURSDAY. MODELS SHOWING PWAT VALUES RISING TOWARDS 1.5 INCHES...WHICH IS WELL ABOVE NORMAL AND LEADS TO THE POTENTIAL FOR LOCALLY HEAVY RAIN OVER WESTERN LAKE SUPERIOR AND THE WESTERN U.P WITH ANY EMBEDDED THUNDERSTORMS. A 1036MB HIGH MOVING INTO NORTHERN ONTARIO ON THURSDAY WILL EXTEND A RIDGE SOUTH TOWARDS LAKE SUPERIOR THURSDAY INTO THURSDAY NIGHT. THAT WILL SHIFT THE LOW LEVEL FLOW TO THE NORTHEAST AND START TO BRING DRIER AIR INTO THE AREA. EXPECT THE DIMINISHING UPPER LEVEL SUPPORT AND GREATER INFLUENCE OF THE HIGH TO CONTINUE INTO THURSDAY NIGHT AS THE HIGH MOVES OVER JAMES BAY. THAT SHOULD REALLY DIMINISH PRECIPITATION CHANCES HEADING INTO FRIDAY...ALTHOUGH THERE COULD BE ENOUGH LINGERING LOW LEVEL MOISTURE TO SUPPORT SOME SHOWERS OVER THE WESTERN U.P. ON THE EDGE OF THE RIDGE. AT THIS POINT...THE WEEKEND LOOKS DRY WITH THE UPPER RIDGE BUILDING OVER CENTRAL CANADA AND THE SURFACE HIGH DROPPING SOUTHEAST INTO THE NEW ENGLAND STATES. THIS WILL KEEP THE UPPER GREAT LAKES REGION UNDER THE WESTERN EDGE OF THE SURFACE RIDGE AND WITH MIXING TO 875MB TEMPS AROUND 10C ON SATURDAY WOULD SUPPORT HIGHS IN THE LOW 70S AND THEN SLIGHTLY HIGHER TEMPS ON SUNDAY WITH A LITTLE BETTER MIXING. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 119 PM EDT MON SEP 21 2015 ARRIVAL OF A FRONT LATE TONIGHT MAY PRODUCE SCT SHRA BUT IS NOT EXPECTED TO BE HEAVY ENOUGH TO IMPACT VSBY AND HAVE A MENTION OF VCSH AT IWD AND CMX TO COVER THIS. GUSTY SOUTH WINDS ARE EXPECTED TO PERSIST TONIGHT WITH A TIGHT PRES GRADIENT OVER THE AREA. THIS SHOULD MINIMIZE LLWS POTENTIAL WITH A LOWER CHANCE OF DEVELOPING A LOW LEVEL INVERSION EXCEPT AT SAW WHERE PUT IN LLWS. VFR CONDITIONS EXPECTED FOR MOST OF THE PERIOD UNTIL TUE MORNING WHEN MVFR CIGS MOVE ACROSS WITH THE COLD FRONT AT ALL SITES. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 520 AM EDT MON SEP 21 2015 HIGH PRESSURE OVER THE LOWER GREAT LAKES WILL SLOWLY EXIT ACROSS THE NEW ENGLAND AS A LOW OVER MANITOBA DEEPENS AND LIFTS NE THROUGH HUDSON BAY TONIGHT THROUGH TUESDAY. AS A RESULT...AN INCREASING PRES GRADIENT WILL SUPPORT S WINDS IN THE 20-25 KNOT RANGE TODAY AND TONIGHT. EXPECT THE LOW TO DRAG A COLD FRONT ACROSS LAKE SUPERIOR TONIGHT THROUGH TUE. BEHIND THE LOW...HIGH PRESSURE ACROSS NORTH DAKOTA TUE MORNING WILL BUILD OVER LAKE SUPERIOR TUE AFTERNOON...BEFORE EXPANDING ACROSS NRN ONTARIO WED. A RIDGE WILL REMAIN THROUGH FRIDAY...BEING REINFORCED BY AN ADDITIONAL AREA OF HIGH PRESSURE SETTLING ACROSS NRN ONTARIO THURSDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...07 MARINE...JLB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1250 PM CDT MON SEP 21 2015 .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 330 AM CDT MON SEP 21 2015 THE PRIMARY FORECAST CONCERNS IN THIS PERIOD ARE PCPN CHANCES... ESPECIALLY FOR WED...AND TEMPERATURES THE NEXT FEW DAYS. SECONDARY CONCERN TODAY IS COVERAGE OF LOW CLOUDS TODAY. MAIN FEATURES FROM UPPER LEVEL CHARTS LAST EVENING WERE A 115 KT JET MAX AT 300 MB PUSHING EWD INTO SRN BC AND A MID LEVEL SHORTWAVE TROUGH ASSOCIATED WITH THAT JET MAX. 12 HOUR HEIGHT FALLS OF UP TO 80 METERS WERE NOTED IN BC AT CWXS AT 500 MB. LATEST WATER VAPOR LOOP IN COMBINATION WITH MOST RECENT RUC MODEL INITIALIZATION SHOWED THESE HAD MOVED INTO SRN ALTA AS OF 08Z. THE OTHER FEATURE OF CONCERN IN STLT IMAGERY WAS THE MOISTURE FROM TD16 MOVING NWD TOWARD SRN AZ. TODAY...LOW CLOUDS WILL BE PROBLEMATIC. THESE WERE CURRENTLY LODGED ACROSS MUCH OF OUR FORECAST AREA. THEY ARE FINALLY STARTING TO LIFT BUT FEEL THEY WILL HAVE AN IMPACT ON HIGHS TODAY AND HOVE TWEAKED AREAS ALONG THE MISSOURI RIVER DOWN A FEW DEGREES. WE WILL HAVE SOME MIXING WITH THE SLY FLOW...BUT THAT MAY ONLY BE TO ABOUT 875 MB. LOW CLOUDS MAY MOVE BACK IN TONIGHT. WE HAVE HAD BEEN CARRYING A SLIGHT CHANCE OF TSTMS...BUT LOOKING AT THINGS CLOSER THE ELEVATED INSTABILITY MAY NOT BE REALIZED. IT MAY END UP BEING DRIZZLE IF ANYTHING. FOR NOW...BACKED OFF TO JUST A SLIGHT CHANCE OF SHOWERS. LOWS SHOULD BE HELD UP WITH SLY FLOW AND AN INCREASE IN LOW LEVEL MOISTURE. MOS GUIDANCE SEEMS REASONABLE WITH LOWER AND MID 60S. THE 00Z NAM SHOWED SOME TSTMS DEVELOPING TUE MORNING OVER PARTS OF ERN NE...AND THAT SCENARIO SEEMS PLAUSIBLE WITH DECENT MID LEVEL LAPSE RATES AND ELEVATED INSTABILITY. TEMPERATURES SHOULD WARM INTO THE 80S IN THE AFTN. KEPT A SLIGHT CHANCE OF TSTMS FOR TUE NIGHT INTO WED MORNING... AS PW VALUES INCREASE TO OVER 1.50 INCHES...BUT BETTER FOCUS MAY BE MORE IN ERN SD/NWRN IA/SWRN MN. THREAT FOR STRONG STORMS AND LOCALLY HEAVY RAIN WILL BE INCREASING IN OUR WRN COUNTIES BY LATE WED AFTN. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 330 AM CDT MON SEP 21 2015 HEAVY RAIN THREAT WITH STRONG STORMS MAY LINGER INTO AT LEAST WED EVENING...WITH CHANCES HIGHEST WEST OF A LINE FROM BEATRICE AND LINCOLN TOWARD WAYNE. DETAILS ON THIS SHOULD BECOME MORE CLEAR BY TOMORROW. SYSTEM THEN SOMEWHAT STALLS OUT OVER THE CNTRL PLAINS THU BEFORE SLOWLY WEAKENING. HAVE SOME POPS MENTIONED UNTIL FRI... THEN IT LOOKS MAINLY DRY. TEMPERATURES SHOULD BE AT OR ABOVE NORMAL THE WHOLE WEEK. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1238 PM CDT MON SEP 21 2015 YESTERDAY THOUGH THE MODELS HINTED AT IT...I DID NOT GO STRONG ENOUGH WITH THE LIFR CONDITIONS THAT DEVELOPED EARLY THIS MORNING. CONDITIONS LOOK EVEN MORE FAVORABLE TONIGHT SO ALL THREE TAF SITES GOING BACK DOWN INTO LIFR MAINLY AFTER 10Z. AFTER 16Z ONCE AGAIN EXPECT CONDITIONS TO IMPROVE TO IFR AND MVFR AS FOG BURNS OFF AND LOW CIGS GRADUALLY LIFT. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...MILLER LONG TERM...MILLER AVIATION...MEYER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
323 PM EDT MON SEP 21 2015 .SYNOPSIS... SURFACE HIGH PRESSURE LOCATED OVER THE NORTH COUNTRY WILL CONTINUE TO PROVIDE THE REGION WITH DRY CONDITIONS AND MILD TEMPERATURES. EXPECTING LARGE SWINGS IN DAILY TEMPERATURES FROM COOL NIGHTTIME LOWS TO WARM DAYTIME HIGH TEMPERATURES. ALSO...EXPECT WARMER TEMPERATURES NEAR THE WARMER LAKE CHAMPLAIN WATERS. WINDS WILL BE LIGHT AND GENERALLY TERRAIN DRIVEN. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... AS OF 330 PM EDT MONDAY...FCST FOCUS TONIGHT WILL BE IMPACTS OF HIGH CLOUDS ON TEMPS AND POTENTIAL FOR PATCHY FROST AND AREAS OF FOG. WATER VAPOR DEEP DRY LAYER ASSOCIATED WITH RIDGE SHIFTING INTO NORTHERN NEW ENGLAND...WHILE MID LEVEL MOISTURE ASSOCIATED S/W TROF OVER THE OHIO VALLEY IS STREAMING INTO OUR REGION. PROGGED 500 TO 200MB RH FIELDS AND SOUNDINGS SHOW MOST OF THE HIGH LEVEL CLOUDS WILL BE FROM THE EASTERN DACKS INTO CENTRAL/EASTERN VT THRU TONIGHT. THINKING THESE CLOUDS COMBINED WITH SLIGHTLY HIGHER BOUNDARY LAYER WINDS BETWEEN 8 AND 14 KNOTS WILL LIMIT FROST POTENTIAL ACROSS OUR DEEPER VT VALLEYS. ALSO...DEVELOPMENT OF FOG WILL BE DELAYED AND LESS IN AREAL COVERAGE THAN LAST NIGHT...AS CROSS OVER TEMPS WILL TAKE LONGER TO REACH. HAVE NOTED THE LATEST HRRR CONTS TO SUPPORT SOME LIGHT RAIN SHOWERS OR SPRINKLES ASSOCIATED WITH S/W ENERGY AND MOISTURE TO IMPACT US...BUT GIVEN DRY LAYER THINKING THIS WILL FALL AS VIRGA. WILL MENTION FOG IN VALLEY SECTIONS OF VT/NORTHERN NY...WITH SOME PATCHY FROST POSSIBLE NEAR SLK AND PARTS OF ESSEX COUNTY VT. NO ADVISORY NECESSARY GIVEN THE SMALL AREAL COVERAGE OF FROST ANTICIPATED. TEMPS WILL BE HIGHLY TERRAIN DEPEND WITH COOLEST VALUES IN THE DEEPER/PROTECTED VALLEYS AWAY FROM LAKE CHAMPLAIN...WITH VALUES RANGING FROM THE MID 30S TO M/U 40S TO MID 50S NEAR LAKE CHAMPLAIN. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... AS OF 330 PM EDT MONDAY...THE LARGE SCALE PATTERN CONTINUES TO SUPPORT DRY CONDITIONS WITH SLIGHTLY ABOVE NORMAL TEMPS THRU WEDS NIGHT. ON TUES WEAKENING MID/UPPER LVL TROF ACROSS THE OHIO VALLEY AND ASSOCIATED MID LEVEL MOISTURE MAY PRODUCE SOME CLOUDS ACROSS OUR REGION. THESE CLOUDS WILL DISSIPATE BY SUNSET AS SFC HIGH PRES LOCATED OVER CENTRAL CANADA BUILDS TWD NORTHERN NY. PROGGED 85H TEMPS CHANGE VERY LITTLE WITH VALUES BETWEEN 7-9C ON TUESDAY...SUPPORTING HIGHS IN THE MID/UPPER 60S MTNS TO L/M 70S WARMER VALLEYS. EXPECTING SLIGHTLY WARMER TEMPS ON TUES NIGHT WITH AREAS OF FOG CONFINED TO THE CLIMO FAVORED VALLEYS OF NORTHERN NY AND EASTERN/CENTRAL VT. TEMPS WILL RANGE FROM THE MID 30S SLK/NORTHEAST KINGDOM TO L/M 50S CHAMPLAIN VALLEY. THERMAL PROFILES SUGGEST A STRONG INVERSION WILL BE PRESENT...RESULTING IN WARMER MID/UPPER SLOPES. LITTLE CHANGE ANTICIPATED ON WEDS WITH WEST TO NORTHWEST FLOW ALOFT AND SURFACE HIGH PRES LOCATED NEAR HUDSON BAY RIDGING TOWARD NORTHERN NY. THIS WILL HELP PUSH A WEAK COLD FRONT ACROSS OUR CWA ON WEDS NIGHT WITH SLIGHTLY COOLER TEMPS AND NORTH WINDS BY THURS. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 PM EDT MONDAY...FAIR, DRY AND SEASONAL CONDITIONS ARE EXPECTED DURING THE EXTENDED PORTION OF THE FORECAST FROM THURSDAY THROUGH MONDAY. A LARGE DOME OF SURFACE HIGH PRESSURE OVER JAMES BAY THURSDAY BUILDS SOUTHWARD INTO THE NORTHEAST FOR THE FRIDAY/SATURDAY TIME-FRAME, THEN OFF THE NEW ENGLAND COAST FOR SUNDAY/MONDAY. MEANWHILE ALOFT WE`LL BE UNDER A GENERAL WEST/NORTHWEST FLOW WHICH WILL KEEP SOME DIURNAL CLOUDS AROUND. TEMPERATURE WILL BE FAIRLY NORMAL, 60S/70S FOR HIGHS AND 40S FOR LOWS. CLEAR SKIES AND LIGHT WINDS AT NIGHT WILL ALSO LEAD TO SOME DENSE FOG IN THE CLIMO FAVORED VALLEYS. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... THROUGH 18Z TUESDAY...VFR CONDITIONS ARE LARGELY EXPECTED THROUGH THE PERIOD UNDER SCT-BKN CIRRUS CLOUDS. ONLY EXCEPTIONS WILL BE SOME LIFR FOG AT KMSS/KSLK FROM 05-11Z AND POSSIBLY AT KMPV FROM 08-12Z. CLOUDS MAY HINDER FOG AT KMPV. LIGHT AND VARIABLE WINDS TODAY AND TONIGHT WILL TURN SOUTH/SOUTHWESTERLY TOMORROW BUT GENERALLY REMAIN LESS THAN 10 KTS. OUTLOOK 18Z TUESDAY THROUGH SATURDAY... MAINLY VFR THROUGH THE PERIOD AS A RIDGE OF HIGH PRESSURE WILL BE OVER THE REGION. VLIFR/LIFR FOG LIKELY FROM 06-14Z AT KSLK/KMPV EACH MORNING AND POSSIBLE ELSEWHERE. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...TABER NEAR TERM...TABER SHORT TERM...TABER LONG TERM...LAHIFF AVIATION...LAHIFF
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
243 PM CDT MON SEP 21 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT) ISSUED AT 234 PM CDT MON SEP 21 2015 A HOT ONE THIS AFTERNOON. MAIN COLD FRONT WITH NW WINDS LOCATED NR LANGDON THRU DEVILS LAKE TO NR JAMESTOWN AT 19Z. TEMPS BOOSTING TO AROUND 90 JUST EAST OF FRONT IN AREA OF WEST-SOUTHWEST WINDS. OTHERWISE TEMPS IN THE 80S WITH A GUSTY SOUTH WIND IN THE RRV INTO NW/WCNTRL MN. HRRR TRIES TO INDICATE SOME PRECIP AHD OF FRONT IN FAR ERN FCST AREA NR 00Z-01Z...BUT BEMIDJI SOUNDINGS FROM GFS/NAM INDICATE CONVECTIVE TEMPS IN THE UPPER 80S. THUS DEFINITELY FEEL LIKE DRY FCST IS THE WAY TO GO. TEMPS TO COOL DRAMATICALLY TONIGHT AND MUCH COOLER ON TUESDAY. SOME MID CLOUDS WILL STREAM EAST LATE TONIGHT INTO TUESDAY...ESP NW HALF OF THE FCST AREA. HIGH TEMPS A GOOD 20-25 DEGREES COOLER. MAIN MID LEVEL MOISTURE SATURATION IS FOCUSED IN WARM ADVECTION ZONE IN NW ND/SE SASK TUESDAY AND MID LEVEL MOISTURE STREAMING EAST RUNNING INTO VERY DRY SUB CLOUD LAYER AIRMASS. THUS FEEL ANY THREAT FOR SHOWERS WILL BE JUST WEST OF OUR CWA...AND WILL HAVE OUR FCST AREA DRY. 12Z NAM AND ECMWF TRIES TO SPIT OUT A LITTLE BIT OF PRECIP WITH THIS MID LEVEL MOISTURE...AND CERTAINLY CAN BE SOME...BUT THINK IT WILL DRY UP BEFORE REACHING THE GROUND. SUBTROPICAL PLUME OF MOISTURE FROM THE DESERT SOUTHWEST ARRIVES INTO ERN SD/SW MN TUESDAY NIGHT AND SPREADS NORTHEAST AND NORTH AS SOUTHERLY 850 MB JET INCREASES. MAIN INSTABILITY SURGE HOWEVER IS MORE SO TOWARD 12Z WED IN THE FAR SOUTH. THUS FOLLOWED WFO DLH LEAD AND SLOWED DOWN ADVANCE OF PRECIP TUES NIGHT...WITH HIGHEST POPS AFTER 06Z WED. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 234 PM CDT MON SEP 21 2015 MOISTURE AXIS SHIFTS A BIT EAST ON WEDNESDAY AS MAIN UPPER LEVEL SHORT WAVE REMAINS WELL TO SOUR SOUTH OVER NEBRASKA INTO WEDNESDAY. KEPT POPS IN THERE FOR SCT SHRA/TSTM ACTIVITY WED INTO THURSDAY BUT UPPER WAVE TO OUR SOUTH STARTS TO WEAKEN AND FALL APART. THUS COVERAGE OF PRECIP NOT GREAT. FOR THURSDAY NIGHT THROUGH MONDAY...BASICALLY LOOK TO STAY IN SOUTHWEST FLOW AS A TROUGH DIGS DOWN THE WEST COAST. BEST MODEL AGREEMENT COMES IN THE FRI/SAT TIME FRAME WITH THE WEATHER LOOKING DRY AND TEMPS WARMING BACK ABOVE NORMAL. BY SUNDAY INTO MONDAY MODELS START TO DIFFER ON THE DETAILS SO CONFIDENCE BEGINS TO WANE. THEREFORE HAVE PRETTY MUCH GONE WITH GUIDANCE PCPN CHANCES WHICH INDICATE SOME LOW END CHANCES. TEMPS STILL LOOK TO REMAIN ABOVE NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1244 PM CDT MON SEP 21 2015 MAIN THING TODAY WILL BE A GRADUAL WIND SWITCH TO THE SW AND THEN WEST THROUGH NW. COULD BE RATHER GUSTY FROM MID AFTERNOON THRU EARLY EVENING BEFORE WINDS BEGIN TO LOSE THEIR GUSTS AGAIN. THERE ARE SOME LOWER CLOUDS BEHIND THE FRONT...CURRENTLY LOCATED OVER SOUTHEAST SASKATCHEWAN...WHICH MAY TRY TO WORK IN OR THIN OUT BY THE TIME THEY ARRIVE HERE. LEFT THE SCATTERED MENTION OF A 4000FT DECK JUST IN CASE. OTHERWISE WINDS SHOULD LIGHTEN UP AFTER MIDNIGHT WITH MAINLY CLEAR SKIES BY THEN. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...RIDDLE LONG TERM...GODON/RIDDLE AVIATION...GODON
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
1229 PM CDT MON SEP 21 2015 .AVIATION...18Z TAF ISSUANCE... LINGERING PATCH OF MVFR FOG IN SWRN OK WILL CONTINUE TO DISSIPATE OVER THE NEXT ONE TO TWO HOURS... IT IS CURRENTLY NOT AFFECTING ANY TAF SITE. VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE PERIOD... WITH LIGHT TO MODERATE SOUTH WINDS. WRN TAF SITES MAY EXPERIENCE S/SW GUSTS UP TO 20 KTS THROUGH THE AFTN. THERE MAY BE A CHANCE OF SOME STRATUS AND/OR MVFR BR IN FAR NRN OK TUE AM. AT THE MOMENT... HOWEVER CONFIDENCE IS TO LOW FOR ANY MENTION IN THE KPNC TAF AT THIS TIME. JTK && .PREV DISCUSSION... /ISSUED 1102 AM CDT MON SEP 21 2015/ DISCUSSION... FOG AND LOW CLOUDS HAVE DIMINISHED IN CENTRAL OKLAHOMA, BUT IS ONLY SLOWLY DISSIPATING IN SOUTHWEST OKLAHOMA AND ADJACENT PARTS OF TEXAS. THE SAME IS TRUE FOR PART OF NORTH CENTRAL OKLAHOMA NEAR THE KANSAS BORDER. TEMPERATURE AND WEATHER GRIDS WERE ADJUSTED TO ACCOMMODATE THIS AND FORECAST A SLOWER RISE IN EARLY AFTERNOON TEMPERATURES IN THESE AREAS. HRRR TEMPERATURES WERE LOADED AND SLIGHT MODIFIED FOR THESE AREAS. OTHERWISE, THE HEAT RETURNS THIS AFTERNOON TO PART OF WESTERN OKLAHOMA AND ADJACENT PARTS OF TEXAS. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 84 66 90 67 / 10 0 0 0 HOBART OK 89 67 93 68 / 0 0 0 0 WICHITA FALLS TX 91 68 94 68 / 0 0 0 0 GAGE OK 92 66 93 67 / 0 0 0 10 PONCA CITY OK 83 66 89 68 / 10 0 0 0 DURANT OK 88 67 92 67 / 10 0 0 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 09/04/04
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1221 PM CDT MON SEP 21 2015 .AVIATION UPDATE...FOR 18Z TAF`S. BNA/CKV/CSV...SURFACE RIDGE REMAINS SITUATED TO OUR WEST WITH A TROUGH EXTENDING NORTHWARD ACROSS THE APPALACHIANS, WHICH IS PROVIDING THE CLOUDINESS WE HAVE SEEN TODAY ACROSS MIDDLE TENNESSEE. AM NOT EXPECTING ANY PRECIPITATION THE NEXT 24 HRS, AS THE DEEPEST MOISTURE IS EXPECTED TO PULL FARTHER EASTWARD. PERHAPS SOME LIGHT RADIATION FOG OVERNIGHT AT CKV & CSV, OTHERWISE LOOK FOR VFR WX THE NEXT 24 HRS. && .PREV DISCUSSION... /ISSUED 539 AM CDT MON SEP 21 2015/ AVIATION 12Z DISCUSSION... UPPER TROUGH AXIS WAS LOCATED JUST UPSTREAM THIS MORNING. THE WEAK UPPER LEVEL DYNAMICS MAY BE ENOUGH TO PRODUCE A FEW SHOWERS ACROSS SOUTHERN MIDDLE TN...BUT SHOULD NOT EFFECT THE TAF AREAS. OTW...THE AXIS WILL MOVE EAST OF THE MID STATE AND THEN INTENSIFY TONIGHT. AS A RESULT...DRIER AIR WILL WIN OUT THIS AFTERNOON AND ESPECIALLY ON TUESDAY. THEREFORE...THE TREND WILL BE TOWARD A DECREASE IN THE MID/UPPER LEVEL CLOUD COVER. SKC SHOULD PREVAIL AFT 00Z. PREV DISCUSSION... /ISSUED 443 AM CDT MON SEP 21 2015/ UPDATE... WITH WEAK UPPER LEVEL DISTURBANCE MOVING ACROSS SRN PORTIONS OF MID STATE AS OF 09Z(4AM CDT)...AND HRRR MODEL SHOWING THIS POSSIBILITY CONTINUING THRU 16Z(11 AM CDT)...WILL UPDATE THE SUITE OF FORECAST PRODUCTS TO MENTION A SLIGHT CHANCE TO CHANCE OF SHWRS ACROSS THESE AREAS THRU 16Z. SOME OF THE ABOVE MENTIONED RAINFALL MAY NOT BE ACTUALLY REACHING THE GROUND PER DRY AIR NOTED ACROSS THIS AREA GENERALLY BELOW 700MB PER MOST RECENT LAPS SOUNDING PROFILES. PREV DISCUSSION.../ISSUED 246 AM CDT MON SEP 21 2015/ SHORT TERM(TODAY-WED NIGHT)... FORECAST QUANDARIES...SKY COVER TIMING EROSION TODAY...TEMPS. A STRAIGHT FORWARD FORECASTS THRU WED NIGHT...WITH STRONG CONSENSUS BETWEEN MODEL SOLUTION RESOLUTIONS. HIGH PRESSURE INFLUENCES AND UPPER LEVEL RIDGING INFLUENCES BUILDING IN FROM THE MS RIVER VALLEY WILL BE THE MAIN WX PLAYERS ACROSS THE MID STATE THRU WED NIGHT. CLOUD COVERAGE APPROACHING 08Z WILL CONTINUE TO PUSH EWD AND OUT OF THE AREA AS THE DAY PROGRESSES...AS UPPER LEVEL TROUGHING INFLUENCES MOVE EWD AND ABOVE MENTIONED UPPER LEVEL RIDGING INFLUENCES BUILD ACROSS THE AREA. WILL THUS TAILOR CLOUD CONDITIONS TODAY FOR A DECREASING CLOUDINESS TREND W MID MORNING THRU EARLY AFTERNOON E. MOCLR SKIES ARE EXPECTED TONIGHT THRU WED NIGHT. SFC HIGH PRESSURE INFLUENCES WILL BUILD INTO THE MID STATE FROM THE SRN OHIO RIVER VALLEY TODAY BEFORE MERGING WITH HIGH PRESSURE INFLUENCES ACROSS THE NE U.S. AS FOR TEMPS...HIGH TEMPS TODAY WILL BE AROUND SEASONAL NORMAL VALUES... AROUND 80 TO LOWER 80S...MID TO UPPER 70S PLATEAU. TEMPS WILL WARM UP TO A FEW DEGREES ABOVE SEASONAL NORMAL VALUES...LOW TO MID 80S...UPPER 70S PLATEAU...BY WED AFTERNOON. LOWS WILL BE A FEW DEGREES BELOW SEASONAL NORMAL VALUES TONIGHT...MAINLY IN THE LOW TO MID 50S. LOWS ARE EXPECTED TO RISE MAINLY INTO THE UPPER 50S ACROSS THE AREA BY WED NIGHT. LONG TERM(THU-SUN)... THE GFS PROGRESSION OF THE EXT WEATHER PATTERN SEEMS TO BE A BIT MORE BELIEVABLE AS OPPOSED TO THE EURO SOLUTION. THE ORIENTATION OF THE UPPER RIDGE AXIS LOOKS A BIT UNORTHODOX AS IT STRETCHES FROM THE DESERT SOUTHWEST NORTHEASTWARD AND THE SOUTHEAST ACROSS THE MID ATLANTIC. MEANWHILE...THE GFS SOLUTIONS SHOWS A GENTLE RETROGRADE MOTION IN REGARD TO WEAK UPPER LEVEL TROUGHING OVER THE SOUTHEASTERN U.S. THEREFORE...IN THIS EXT FCST...WILL LEAN TOWARD THE GFS SOLUTION. ON THURSDAY...THE WEAK UPPER TROUGH WILL RESIDE ACROSS GA AND EASTERN TN. THIS WILL CONTINUE TO KEEP MIDDLE TN ON THE DRY SIDE IN THE MID AND UPPER LEVELS. IN THE LOWER LEVELS...A LARGE SFC HIGH OVER SOUTHERN PORTIONS OF THE HUDSON BAY WILL PROVIDE MAINLY AN EASTWARD COMPONENT IN THE LOWER LEVELS. THUS...THE OVERALL PATTERN WILL BE ON THE DRY SIDE. AS WE MOVE TOWARD THE WEEKEND...THE AFOREMENTIONED SFC HIGH WILL MOVE SOUTHEASTWARD AND REACH THE NEW ENGLAND AREA BY SUNDAY. AS A SOUTHWESTERN SFC RIDGE DEVELOPS TOWARD THE CAROLINAS...MORE OF A SOUTHERLY LOW LEVEL WIND COMPONENT WILL SET UP IN OUR NECK OF THE WOODS. IN THE UPPER LEVELS...THE UPPER LEVEL TROUGH WILL NOW BE LOCATED WEST OF THE MID STATE. THIS WILL PROVIDE A REBOUND OF MOISTURE IN THE MID AND UPPER LEVELS. SO FOR THE FCST...WILL BEGIN TO BRING BACK LOW CHANCES OF SHOWER ACTIVITY...MAINLY ACROSS EASTERN AREAS. THE EURO IS DRY THROUGHOUT THE PERIOD...SO EVEN THOUGH THATS NOT THE MODEL OF CHOICE...A BLEND AND A TREND TOWARD ISC GRIDS WILL KEEP POPS ON THE LOW SIDE FOR NOW. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 55 83 58 85 / 10 0 0 0 CLARKSVILLE 51 82 53 84 / 0 0 0 0 CROSSVILLE 52 77 55 79 / 10 0 0 0 COLUMBIA 51 83 54 84 / 10 0 0 0 LAWRENCEBURG 54 82 56 83 / 10 0 0 0 WAVERLY 53 83 54 84 / 0 0 0 0 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ ROSE
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
101 PM CDT MON SEP 21 2015 .AVIATION... /18Z TAFS/ VFR CONDITIONS ARE EXPECTED ACROSS AREA SITES THROUGH THE FORECAST PERIOD. MID TO UPPER LEVEL MOISTURE WILL CONTINUE TO PUSH TO THE EAST AND ACROSS THE FOUR CORNERS REGION AND INTO OUR AREA THROUGH TUESDAY. THIS MOISTURE IS ASSOCIATED WITH TROPICAL DEPRESSION 16-E CURRENTLY LOCATED OVER THE NORTHWEST PORTION OF MEXICO. AT LOWER LEVELS...MOISTURE WILL BE LIMITED WITH FEW/SCT CLOUDS AROUND 4 TO 6 KFT FOR THE FORECAST CYCLE. WINDS WILL BE MAINLY FROM THE SOUTHEAST AT 5 TO 8 KNOTS THROUGH THIS EVENING AND THEN BECOMING LIGHT AND VARIABLE OVERNIGHT. ON TUESDAY...THE SOUTHERLY WIND FLOW TAKES CONTROL ONCE AGAIN WITH SPEEDS OF 5 TO 10 KNOTS AND OCCASIONAL GUSTS UP TO 16 KNOTS. && .PREV DISCUSSION... /ISSUED 655 AM CDT MON SEP 21 2015/ AVIATION.../12Z TAFS/ MAIN FORECAST ISSUE WILL BE AT SAT/SSF FOR THE NEXT FEW HOURS WHERE CIGS WILL OSCILLATE BETWEEN SCT010 AND BKN010...THUS HAVE LEFT IN A TEMPO GROUP THROUGH 14Z FOR BORDERLINE MVFR-IFR CIGS. A WEAK UPPER LEVEL TROUGH AND MIDLEVEL CLOUD DECK WILL CONTINUE TO MOVE E-SE OVER THE NEXT FEW HOURS. THESE CLOUDS HELPED PREVENT PATCHY FOG FROM DEVELOPING EXCEPT IN THE COASTAL PLAINS...SO HAVE REMOVED FOG FROM AUS. VFR CONDITIONS SHOULD PREVAIL EVERYWHERE BY 15Z AND SHOULD CONTINUE THROUGH THE TAF PERIOD WITH E-SE WINDS UNDER 10 KTS BECOMING LIGHT AND VARIABLE BY THE EVENING. PREV DISCUSSION... /ISSUED 417 AM CDT MON SEP 21 2015/ SHORT TERM (TODAY THROUGH TUESDAY)... AREA RADAR DATA SHOWS AN OUTFLOW BOUNDARY CURRENTLY LOCATED ALONG A BURNET TO ROUND ROCK TO GIDDINGS LINE. THIS FEATURE IS WEAK AS SURFACE OBSERVATIONS DO NOT SHOW ANY WIND SHIFT NORTH OF THE MENTIONED AREAS. SURFACE OBSERVATIONS DO SHOW LIGHT WINDS AND PLENTY OF MOISTURE EAST OF I-35. CAN/T RULE OUT SOME PATCHY FOG THIS MORNING EAST OF I-35 AND WE/LL CONTINUE TO MENTION IN THE LATEST FORECAST. OTHERWISE...INFRARED SATELLITE CONTINUES TO SHOW PLENTY OF MID AND HIGH LEVEL CLOUD COVER ACROSS THE REGION. THIS CLOUD COVER WILL GRADUALLY THIN FROM NORTH TO SOUTH TODAY AS SOME WEAK UPPER LEVEL SHORT WAVE TROUGHS MOVE THROUGH EAST TEXAS. A DRY AND WARM FORECAST IS IN STORE TODAY AND TOMORROW AS MID- LEVEL RIDGING REMAINS THE DOMINANT WEATHER FEATURE. WE/LL ONCE AGAIN SEE HIGHS IN THE 90S AND LOWS IN THE MID 60S AND 70S. LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)... THE SUBTROPICAL RIDGE AXIS CONTINUES THROUGH WEDNESDAY FOR MORE ABOVE NORMAL TEMPERATURES AND DRY WEATHER ACROSS SOUTH CENTRAL TEXAS. THE RIDGE BEGINS TO BREAK DOWN ON THURSDAY AS AN UPPER LOW MOVES INTO THE CENTRAL PLAINS STATES. THE FORECAST THROUGH THE REMAINDER OF THE PERIOD WILL BE LARGELY DETERMINED ON THE DEVELOPMENT OF AN UPPER LEVEL LOW PRESSURE SYSTEM OVER THE SOUTHERN U.S. PLAINS. THE OPERATIONAL ECMWF AND GFS NOW DIFFER CONSIDERABLY WITH THIS FEATURE AS COMPARED TO PREVIOUS MODEL DATA. FOR NOW...WE/LL GO WITH CONTINUED DRY WEATHER ALONG WITH A VERY GRADUAL COOL DOWN. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 73 96 72 95 70 / - - - 0 0 AUSTIN BERGSTROM INTL AIRPORT 68 95 68 94 66 / - - - 0 0 NEW BRAUNFELS MUNI AIRPORT 70 96 69 97 68 / - - 0 0 0 BURNET MUNI AIRPORT 71 94 70 93 68 / - - - 0 0 DEL RIO INTL AIRPORT 72 95 72 95 71 / - - 0 0 0 GEORGETOWN MUNI AIRPORT 70 94 71 94 68 / - - - 0 0 HONDO MUNI AIRPORT 68 96 69 95 68 / - - 0 0 0 SAN MARCOS MUNI AIRPORT 70 94 69 94 68 / - - 0 0 0 LA GRANGE - FAYETTE REGIONAL 71 95 69 94 68 / - - 0 0 - SAN ANTONIO INTL AIRPORT 73 95 72 94 71 / - - 0 0 0 STINSON MUNI AIRPORT 72 95 71 95 70 / - - 0 0 0 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...17 SYNOPTIC/GRIDS...ALLEN PUBLIC SERVICE/DATA COLLECTION...33
Area Forecast Discussion National Weather Service Midland/Odessa TX 1251 PM CDT MON SEP 21 2015 .DISCUSSION... Please see the 18Z aviation discussion below. && .AVIATION... A large area of showers and thunderstorms is expected to move into southeast New Mexico and southwest Texas by this evening. Guidance indicates KCNM has the best chance to see a prolonged period of shower/thunderstorm activity tonight as well as potential ceiling/visibility reductions to IFR through Tuesday morning. Uncertainty regarding storm activity increases further east, though have included a TEMPO for KHOB and will defer to later shifts for inclusion of thunderstorms at other TAF sites as conditions warrant. Otherwise, VFR conditions will prevail with light southerly to southeasterly winds through the period. && .PREV DISCUSSION... /issued 408 AM CDT MON SEP 21 2015/ DISCUSSION...As of 4:00 AM CDT Monday...The main weather maker for the next couple of days will be EPAC TD 16-E which is moving across south central Baja California Sur. Southwesterly shear is displacing the thunderstorm activity into Sonora Mexico. Ridging is centered over West Texas/SE New Mexico. As the remnants of TD 16-E move into the Desert SW mid level moisture and instability will increase across the Davis and Guadalupe Mtns. Both the high resolution HRRR and RAP13 models and the mesoscale models indc convection possible over the Mtns thru mid week. The mid/upper level feature associated with this system will move NE through Northern New Mexico tonight/Tuesday with the ridge flattening. Have slight chc pops as far east as the Western Permian Basin tonight/Tuesday. With the moist ground from recent rains have trended temps a little below MOS guidance. Medium range models start to diverge mid week. The GFS is weaker and further north with the remnant mid/upper level shortwave... placing it in the Northern Plains by Thursday with broad ridging centered over the Desert SW. The ECMWF keeps a stronger mid/upper level shortwave further south with the ridge further west. The ECMWF is significantly wetter and cooler for the CWA...especially the Permian Basin and Trans Pecos Thursday thru Saturday. Will keep thunderstorm chances in the Mtns Wed/Thu...and the CWA dry Friday thru next weekend under weak ridging. Strobin && .MAF WATCHES/WARNINGS/ADVISORIES... NM...NONE. TX...NONE. && $$ 84
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
325 PM EDT MON SEP 21 2015 .SYNOPSIS... HIGH PRESSURE EXTENDED FROM NEW ENGLAND...DOWN THE APPALACHIANS...INTO THE CAROLINAS...AND LOW PRESSURE WAS OVER GEORGIA WITH A TROF TRAILING INTO THE TENNESSEE VALLEY. LITTLE CHANGE IN THE WEATHER PATTERN IS EXPECTED THROUGH WEDNESDAY...AS HIGH PRESSURE REMAINS OVER THE EASTERN UNITED STATES. LOW PRESSURE WILL BE OFF THE SOUTHEAST COAST TUESDAY THROUGH FRIDAY. && .NEAR TERM /THROUGH TUESDAY/... AS OF 315 PM EDT MONDAY... SHORT WAVE ENTERING WESTERN MISSISSIPPI WILL SEPARATE MORE FROM THE NORTHERN STREAM BY TUESDAY AND BEGIN TO CLOSE OFF OVER THE SOUTHEAST UNITED STATES. AT THE SURFACE...THE HIGH MOVE NORTHEAST OUT OF NEW ENGLAND AND LOW PRESSURE OFF THE SOUTHEAST COAST DRIFTS WEST. THE NET RESULT WILL BE PERSISTENT AND DEEP EAST TO NORTHEAST WINDS. FORECAST LIFTED INDEX AND OTHER STABILITY PARAMETERS SHOWED A WELL FORMED WEDGE AND STABLE AIR REMAINING OVER THE FORECAST AREA. THE BULK OF THE DEEP MOISTURE MOVES NORTHEAST OUT OF THE FORECAST AREA BY TUESDAY MORNING. BUT SATURATED WITH ENOUGH UPSLOPE TO KEEP OCCASIONAL LIGHT RAIN AND DRIZZLE IN THE FORECAST...ESPECIALLY ALONG THE EAST OF THE BLUE RIDGE TONIGHT. NOT AS MUCH PRECIPITATION EXPECTED TO TUESDAY BUT STILL ENOUGH LOW LEVEL MOISTURE FOR ABUNDANT CLOUD COVER. THIS WILL LIMIT TEMPERATURE RISE DURING THE DAY. WENT WELL BELOW GUIDANCE FOR MAXIMUM TEMPERATURES ON TUESDAY. EXPECTING LOW CLOUDS AND FOG FOR MOST OF THE NIGHT ALONG AND OF THE EAST SIDE OF THE RIDGES. HRRR SHOWED THE RAIN CURRENTLY OVER THE EASTERN COUNTY WARNING AREA MOVING NORTHEAST BY 00Z THEN MORE LIGHT RAIN DEVELOPING BY LATE IN THE EVENING. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... AS OF 330 PM EDT MONDAY... SPLIT FLOW REGIME WILL BE IN PLACE THROUGH THE PERIOD...WITH THE STRONGER NORTHERN STREAM REMAINING ACROSS THE NORTHERN TIER OF STATES WHILE THE SOUTHERN STREAM TAKES A DETOUR FROM THE SOUTHWEST US THROUGH THE GULF OF MEXICO. THIS WILL FAVOR DEVELOPMENT OF A CLOSED LOW OVER THE SOUTHEAST US BY TUESDAY NIGHT THAT WILL SLOWLY RETROGRADE TO THE TENNESSEE VALLEY BY FRIDAY NIGHT. GUIDANCE IS IN RELATIVELY GOOD AGREEMENT WITH THE OVERALL SYNOPTIC PATTERN BUT THERE ARE ENOUGH DIFFERENCES TO CREATE GREATER THAN AVERAGE UNCERTAINTY IN PRECIPITATION POTENTIAL. MOST GUIDANCE INDICATES STRONG HIGH PRESSURE SLIDING THROUGH THE GREAT LAKES REGION WITH SOME LOWER THETA/E AIR WILL WEDGE DOWN THE EASTERN SEABOARD AND HELP SUPPRESS TROPICAL MOISTURE FROM ADVECTING INTO THE REGION FROM THE SOUTHEAST. A NOTABLE EXCEPTION TO THIS SCENARIO IS THE DETERMINISTIC GFS MODEL WHICH FOR SEVERAL CONSECUTIVE RUNS IS NOT AS ROBUST WITH THE HIGH PRESSURE WEDGE AND CONSEQUENTLY BRINGS MUCH HIGHER PRECIPITATION CHANCES TO THE REGION STARTING LATE THURSDAY INTO FRIDAY. BELIEVE THE GFS IS DISCOUNTING THE STRENGTH OF THE WEDGE A BIT TOO MUCH AND AT THIS TIME WILL SHADE THINGS TOWARD LOWER PRECIPITATION CHANCES...THOUGH THIS IS FAR FROM A SETTLED MATTER AND WILL BE CAREFULLY WATCHING TRENDS IN LATER MODEL RUNS AND ENSEMBLES. EXPECT TEMPERATURES TO BE RUNNING A FEW DEGREES BELOW NORMAL WITH HIGHS GENERALLY IN THE LOW TO MID 70S EAST OF THE BLUE RIDGE AND UPPER 60S/LOW70S WEST...AND LOWS IN THE 50S. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 330 PM EDT MONDAY... UNCERTAINTY WILL PERSIST INTO THE WEEKEND BUT GUIDANCE SEEMS TO BE COMING AROUND TO AN UNSETTLED AND WETTER SOLUTION. THE CLOSED LOW OVER THE TENNESSEE VALLEY WILL BEGIN OPENING UP AND PULLING OUT TO THE NORTHEAST AS SOUTHERN STREAM JET ENERGY PICKS UP STEAM AND DRIVES DEVELOPMENT OF A COASTAL LOW OFF OF NORTH CAROLINA BY SUNDAY NIGHT. DEFORMATION ON THE BACKSIDE OF THE DEVELOPING LOW COMBINED WITH UPPER JET DIVERGENCE AND DEEP MOISTURE WILL BE ENOUGH TO KEEP SOME DEGREE OF PRECIPITATION IN THE FORECAST THROUGHOUT THE WEEKEND UNTIL THE LOW DEEPENS AND STARTS TO PULL AWAY ON MONDAY. WILL BEGIN THE PROCESS OF TRENDING PRECIPITATION CHANCES UPWARD BUT WILL NOT GO TOO FAR TOWARD THE LATEST DETERMINISTIC ECMWF THAT IS VERY WET. LATER ENSEMBLE GUIDANCE WILL HELP BRING THIS PERIOD INTO FOCUS AS IT DRAWS BEAR. NORTHEASTERLY FLOW WILL CONTINUE TO KEEP OUR TEMPERATURES BELOW NORMAL WITH HIGHS GENERALLY IN THE UPPER 60S TO LOWER 70S AND LOWS IN THE 50S. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... AS OF 140 PM EDT MONDAY... SURFACE BASED WEDGE WAS WELL ESTABLISHED OVER THE REGION THIS AFTERNOON AND AND THIS PATTERN WILL PERSIST THROUGH THE 18Z END OF THE TAF FORECAST PERIOD. WIND UNDER THE INVERSION WERE NORTHEAST TO EAST WHICH RESULTED IN AN INFLOW OF ATLANTIC MOISTURE AND IFR TO LOW END MVFR CEILINGS. THIS UPSLOPE AIDED BY SHORT WAVE ENERGY WAS GENERATING LIGHT TO MODERATE RAIN AND ASSOCIATED MVFR VISIBILITIES ALONG AND EAST OF THE BLUE RIDGE. LATEST RADAR TRENDS AND SHORT TERM GUIDANCE SHOWED THERE WILL BE A BREAK IN THE RAIN ROUGHLY BETWEEN 23Z/7PM AND 03Z/11PM. HIGH CONFIDENCE THAT CEILINGS WILL LOWER TO IFR OR LIFR OVERNIGHT. LIGHT RAIN AND DRIZZLE WILL BECOME WIDESPREAD FROM 03Z/11PM TO 12Z/8AM. THE LATEST LOCAL WRF RUN AND BUFKIT SUGGESTED A VERY SLOW IMPROVEMENT ON TUESDAY. IT IS POSSIBLE THAT CEILINGS MAY REMAIN IFR UNTIL AFTER 18Z/2PM. EXTENDED AVIATION DISCUSSION... THE WEDGE WILL GRADUALLY DISSIPATE BY MIDWEEK ALLOWING CONDITIONS TO RETURN TO VFR WITH DRY WEATHER WEDNESDAY AND THURSDAY. FORECAST MODELS ARE TRENDING TOWARD MORE PRECIPITATION AND POOR FLYING CONDITIONS ON FRIDAY AND SATURDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS SHORT TERM...MBS LONG TERM...MBS AVIATION...AMS/PM