Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 10/18/13


AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
859 PM MDT THU OCT 17 2013 .UPDATE...MDLS CONTINUE TO GENERATE ENHANCED BANDS OF PCPN OVER THE CWFA TONIGHT INTO FRIDAY MORNING. BANDS ALREADY APPARENT ALONG NORTHERN BORDER THIS EVENING. TIMING WISE...IT MAY BE A LITTLE LATER FORMING OVER THE DENVER BUT IT COULD LAST UNTIL AROUND 15Z AS WELL. THE LATEST NAM12 AND RUC INDICATE A 3-HR QPF OF AROUND ONE QUARTER INCH AROUND 12Z FRIDAY MORNING...SO THE MORE ENHANCED BANDS OF SNOW AT THAT TIME...COULD IMPACT THE MORNING COMMUTE. ACCUMULATIONS WILL LIKELY BE CONFINED THE GRASSY AREAS...WITH THE WARM PAVEMENT MELTING ANY SNOWFALL. WILL ADJUST THE GRIDS WITH A BIT MORE SNOWFALL AROUND 12Z...BUT THAT WILL BE IT FOR NOW. && .AVIATION...HAVE DELAYED THE TIMING OF PCPN AT KDEN BY AN HOUR A COUPLE OF HOURS...WHICH TRANSLATES INTO A LATER DEPARTURE TIME AS WELL FRIDAY MORNING. THE LATEST RUC AND NAM12 SHOW BETTER QPF OVER DENVER AROUND 12Z...SO SNOWFALL IN THE MORE ENHANCED BANDS COULD PRODUCE IFR CONDITIONS IN BRIEF MODERATE TO HEAVY SHOWERS IN THE 10Z-13Z WINDOW. COULD SEE AN INCH OR TWO IN THE GRASSY AREAS AROUND THAT TIME...BUT PAVEMENT WILL BE TOO WARM FOR ANY ACCUMULATIONS THERE. && .PREV DISCUSSION... /ISSUED 354 PM MDT THU OCT 17 2013/ SHORT TERM...UPPER TROUGH CURRENTLY MOVING ACROSS NORTHERN ROCKIES WITH INCREASING NORTHWEST FLOW ALOFT ACROSS COLORADO. LIFT AND MOISTURE HAD BEEN INCREASING...WITH RADAR SHOWING SOME ECHOES ACROSS LARIMER COUNTY EXTENDING NORTH INTO WYOMING. ALSO SOME SHOWERS OVER THE MOUNTAINS AIDED BY GOOD OROGRAPHICS. MODELS SIMILAR IN TAKING THE TROUGH EAST INTO THE NORTHERN PLAINS TONIGHT WITH SOME SLIGHT DIGGING SOUTH ACROSS NORTHERN COLORADO. ACROSS MOUNTAINS AND FOOTHILLS...SHOULD SEE SNOW BECOME A BIT MORE WIDESPREAD...ESPECIALLY ZONES 33 AND 35. WINTER WEATHER ADVISORY BEGINS AT 03Z FOR THESE ZONES AND INCLUDES ZONE 34 AND THIS TIMING STILL SEEMS REASONABLE. SNOW ACCUMULATIONS SHOULD RANGE FROM 3 TO 7 INCHES BY FRIDAY MORNING...WITH THE HIGHER AMOUNTS ACROSS ZONES 33 AND 35. AMOUNTS MAY BE A BIT LESS ACROSS FURTHER SOUTH ACROSS SUMMIT COUNTY...WILL MAINTAIN THE ADVISORY THERE. AS FOR ZONE 31...A FEW LOCATIONS ALONG THE WEST FACING SLOPES COULD GET CLOSE TO ADVISORY AMOUNTS. ACROSS PLAINS...EXPECT PRECIPITATION TO DEVELOP AND SPREAD SOUTH DURING THE EVENING AS LOW LEVEL MOISTURE INCREASING. MAIN BATCH OF COLD AIR ADVECTION TO SPREAD SOUTH AFTER 03Z. FROM OBSERVATIONS AND FORECAST SOUNDINGS...THERE SHOULD BE A MIX OF RAIN AND SNOW ACROSS MUCH OF THE PLAINS FROM ROUGHLY DENVER AND AKRON NORTHWARD...WITH ALL SNOW NEAR THE WYOMING BORDER. BY MIDNIGHT WOULD EXPECT THE PRECIPITATION TO BE ALL SNOW ACROSS ALL THE PLAINS. LATEST MODELS STILL INDICATING AN AREA OF HIGHEST SNOW ACCUMULATIONS FROM NORTHERN WELD COUNTY ACROSS MORGAN INTO WASHINGTON COUNTIES. APPEARS TO BE THE RESULT OF CSI DUE TO JET IN VICINITY. WITH NORTHWEST FLOW ALOFT AND JET IN VICINITY...THIS COULD BE CSI BANDED. WILL HOIST A WINTER WEATHER ADVISORY FOR ZONES 38..42..44 AND 48 AND 49 BEGINNING AT 03Z AND GOING THROUGH 15Z AS AMOUNTS SHOULD BE IN THE 3 TO 5 INCH RANGE. LESSER AMOUNTS ELSEWHERE ACROSS THE PLAINS WITH AROUND AN INCH FOR THE DENVER BOULDER AREA. THERE IS A SLIGHT CHANCE THAT THIS HEAVIER BAND COULD SHIFT SOUTHWEST TOWARD DENVER OVERNIGHT. FOR NOW WILL KEEP THIS BAND NORTHEAST OF DENVER. ON FRIDAY...THE TROUGH AND LIFT MOVES EAST OF THE AREA WITH DRIER AND SUBSIDENT NORTHWEST FLOW ALOFT. SHOULD SEE IMPROVING CONDITIONS THROUGH THE MORNING WITH SNOW GRADUALLY ENDING FROM NORTHWEST TO SOUTHEAST. THERE MAY BE A FEW LINGERING SNOW SHOWERS ACROSS THE MOUNTAINS DURING THE AFTERNOON DUE TO OROGRAPHICS. TEMPERATURES TO BE COOLER WITH HIGHS IN THE 40S CROSS THE AREA...THOUGH MAY BE A BIT COOLER IN AREAS OF DECENT SNOW COVER. MODELS SHOW NORTHWEST WINDS INCREASING ACROSS THE FAR EASTERN PLAINS DURING THE AFTERNOON. COULD SEE SOME GUSTS TO 30 MPH AS A RESULT. LONG TERM...WEATHER THROUGH THE MEDIUM AND LONG RANGE PORTION OF THE FORECAST IS GOING TO BE DOMINATED BY A STRONG UPPER RIDGE OVER THE EASTERN PACIFIC AND WESTERN UNITED STATES. RIDGING OVER THE WESTERN HALF OF THE COUNTRY IS GOING TO BE HELD IN PLACE BY A DEVELOPING LONG WAVE TROUGH OVER THE EASTERN THIRD OF THE CONTINENT. WITH THE RIDGE AXIS TO OUR WEST...COLORADO WILL BE UNDER DRY AND MILD NORTHWESTERLY FLOW ALOFT THROUGH THE END OF NEXT WEEK. THE ECMWF AND GFS BRING A WEAK SHORT WAVE OVER THE STATE EITHER SUNDAY NIGHT OR MONDAY NIGHT. WENT WITH THE ECMWF SOLUTION WHICH SHOWS SOME LIGHT PRECIPITATION...MAINLY OVER THE MOUNTAINS SUNDAY NIGHT. HAVE LEFT THE REST OF THE FORECAST PACKAGE DRY ACROSS THE FORECAST AREA. TEMPERATURE-WISE...WITH THE NORTHWESTERLY FLOW ALOFT...WE WILL BE SUSCEPTIBLE TO ANY WEAK SURGES OF COOLER AIR OUT OF THE NORTHERN PLAINS. FOR THIS REASON HAVE HELD ONTO TEMPERATURES THAT ARE SLIGHTLY COOLER THAN NORMAL FOR THE MIDDLE OF OCTOBER. NIGHTTIME LOWS WILL HAVE A TENDENCY TO SLIP DOWN TO THE LOWER AND MID 30S ON THE PLAINS EACH MORNING. AVIATION...MOISTURE CURRENTLY INCREASING ACROSS THE AREA AS NORTHEAST WINDS CONTINUE. SHOULD BEGIN TO SEE CEILINGS OF AROUND 7000 FEET AGL BY 00Z...THEN GRADUALLY LOWER THROUGH THE EVENING. RAIN SHOWERS TO INITIALLY DEVELOP...MAY BE MIXED WITH SNOW AFTER 03Z...THEN CHANGE OVER TO ALL SNOW AFTER MIDNIGHT. MVFR CONDITIONS TO PREVAIL OVERNIGHT...WITH THE POTENTIAL FOR IFR CONDITIONS BETWEEN 09Z AND 13Z. AT THIS TIME SNOW ACCUMULATIONS OF AROUND AN INCH CAN BE EXPECTED WITH A SLIGHT CHANCE OF AROUND 2 TO 3 INCHES IF THE HEAVIER BAND OF SNOW MOVES TOWARDS DENVER. NORTHEAST WINDS OF AROUND 10 KTS TO PREVAIL OVERNIGHT. SNOW SHOULD BE ENDING ACROSS THE AREA AROUND 15Z AS DRIER NORTHWEST FLOW DEVELOPS. CEILINGS TO GRADUALLY IMPROVE AT THAT TIME...BECOMING VFR AROUND 17Z. HYDROLOGY...NO CONCERNS AT THIS TIME. SNOW TO DEVELOP DURING THE EVENING AND CONTINUE OVERNIGHT. ACCUMULATIONS TO RANGE FROM 3 TO 7 INCHES ALONG THE FOOTHILLS BY FRIDAY MORNING...HIGHEST ACROSS LARIMER COUNTY. && .BOU WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 9 AM MDT FRIDAY FOR COZ038-042-044- 048-049. WINTER WEATHER ADVISORY UNTIL NOON MDT FRIDAY FOR COZ033>035. && $$ SHORT TERM...COOPER LONG TERM....DANKERS AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
340 PM MDT WED OCT 16 2013 .SHORT TERM...MID LEVEL DISTURBANCE MOVING ACROSS SOUTHEAST COLORADO WITH SUBSIDENCE SPREADING ACROSS CFWA. STILL SOME CLOUDS ALONG THE CONTINENTAL DIVIDE AND WEAK OROGRAPHIC LIFT GENERATING A FEW LIGHT SNOW SHOWERS. SHOWERS SHOULD BE ENDING SHORTLY AS AIRMASS CONTINUES TO DRY OUT. WEAK SHORTWAVE RIDGE TO MOVE ACROSS AREA OVERNIGHT WITH FLOW ALOFT BECOMING NORTHWEST. MAINLY CLEAR SKIES TO PREVAIL. OVERNIGHT TEMPERATURES TO BE FAIRLY CHILLY DUE TO LIGHT WINDS AND CLEAR SKIES. ON THURSDAY...NORTHWEST FLOW ALOFT TO CONTINUE AS AN UPPER LEVEL DISTURBANCE MOVES INTO THE NORTHERN GREAT BASIN. MOISTURE WILL BE ON THE INCREASE BY THE AFTERNOON WITH INCREASING OROGRAPHICS. THOUGH MOST OF THE MID LEVEL QG ASCENT STAYS TO THE NORTH AND WEST...THERE IS ENOUGH LIFT TO INCREASE POPS A BIT FURTHER ACROSS THE MOUNTAINS AND FOOTHILLS. SNOW ACCUMULATIONS OF UP TO 2 INCHES WILL BE POSSIBLE BY THE EVENING. AS FOR FOOTHILLS...APPEARS TEMPERATURES SHOULD BE WARM ENOUGH FOR MAINLY RAIN...WITH A MIX OF RAIN AND SNOW POSSIBLE HIGHER AREAS NEAR THE WYOMING BORDER. ACROSS PLAINS...COLD FRONT TO MOVE ACROSS THE AREA DURING DURING THE AFTERNOON...WITH MODELS SHOWING THE MAIN COLD AIR ADVECTION DURING THE EVENING. CROSS SECTIONS KEEP UPSLOPE FAIRLY SHALLOW THROUGH THE AFTERNOON. BUT INCREASING MID LEVEL ASCENT ENOUGH TO KEEP A SLIGHT CHANCE OF SHOWERS GOING. DID INCREASE THE POPS ACROSS ZONE 38 WHERE THE GREATER LIFT WILL BE. THERE COULD BE A RAIN/SNOW MIX NEAR THE WYOMING BORDER ALONG THE HIGHER AREAS OF THE CHEYENNE RIDGE. OVERALL CURRENT TEMPERATURE GRIDS SEEM REASONABLE...IN LINE WITH LATEST GUIDANCE. .LONG TERM...THURSDAY NIGHT WILL BE VERY ACTIVE ACROSS THE FORECAST AREA AS A SHORT WAVE RIDING DOWN THE BACK SIDE OF A STRONG RIDGE OVER THE PACIFIC NORTHWEST MOVES OVER THE STATE. THE DISTURBANCE WILL CONTAIN QUITE A BIT OF FRONTOGENESIS AT MID- LEVELS DUE TO STRONG CYCLONIC CURVATURE IN THE WIND FIELD AND A STRONG NORTHERLY JET ALOFT APPROACHING THE AREA FROM THE NORTH. MOUNTAIN AREAS SHOULD PICK UP A FAIR AMOUNT OF SNOWFALL WHICH MAY ALSO SPREAD EASTWARD OVER THE NORTHERN FRONT RANGE FOOTHILLS. WILL ISSUE A WINTER WEATHER ADVISORY FOR ZONES 33...34 AND 35 STARTING A 9 PM TOMORROW EVENING THROUGH MIDDAY FRIDAY. FOUR TO 8 INCH ACCUMULATIONS WILL BE POSSIBLE IN THOSE AREAS. AT LOW LEVELS... UPSLOPE FLOW WILL BE CONTINUING ON THE PLAINS WHICH WILL ALSO GIVE THE MOISTENING AIRMASS JUST A LITTLE BIT MORE LIFT. ON THE PLAINS...TEMPERATURES MAY STILL BE WARM ENOUGH IN THE EVENING FOR THE PRECIPITATION TO BEGIN AS RAIN. THROUGH THE NIGHT...EXPECT TEMPERATURES TO DROP TO THE UPPER 20S AND LOWER 30S WITH PRECIPITATION CHANGING TO SNOW. LIGHT ACCUMULATIONS WILL BE POSSIBLE ACROSS THE PLAINS...BUT MOSTLY LESS THAN 2 INCHES EXCEPT ON THE PALMER DIVIDE. ALL OF THE MODELS ARE IN CLOSE AGREEMENT IN MOVING THE UPPER DISTURBANCE OUT OF THE STATE QUICKLY ON FRIDAY. MOST PRECIPITATION WILL BE OUT OF THE STATE BY NOON...EXCEPT FOR SOME LINGERING SHOWERS OVER THE MOUNTAINS. BEYOND THAT...THE MODELS ALL SHOW MODERATE NORTHWEST FLOW ACROSS COLORADO AS THE WEST COAST RIDGE DE-AMPLIFIES AND EXTENDS TO THE DESERT SOUTHWEST. THIS WILL BRING AN EXTENDED PERIOD OF DRY WEATHER TO THE STATE WITH TEMPERATURES CLIMBING TO AROUND SEASONAL NORMALS. && .AVIATION...NORTHEAST WINDS CURRENTLY AT AREA AIRPORTS. BOTH NAM AND HRRR SHOW WINDS SHIFTING TO THE NORTHWEST BY 00Z THEN SOUTHWEST DURING THE EVENING SPEEDS TO REMAIN LESS THAT 10 KTS. WINDS TO BECOME NORTHWEST AFTER 15Z THURSDAY BEHIND A PASSING WEAK COLD FRONT...THEN NORTHEAST BY AROUND 18Z. SPEEDS SHOULD REMAIN LESS THAN 10 KTS. MID AND HIGH LEVEL MOISTURE TO INCREASE DURING THE DAY...CEILINGS SHOULD REMAIN ABOVE 10000 FEET. A FEW RAIN SHOWERS POSSIBLE AFTER 21Z...MAINLY NORTH AND WEST OF THE AREA. VFR TO PREVAIL. && .HYDROLOGY...MOISTURE TO INCREASE DURING THE DAY THURSDAY AHEAD OF THE NEXT WEATHER SYSTEM...WITH SHOWERS DEVELOPING BY THE AFTERNOON. TEMPERATURES WILL BE COLD ENOUGH FOR SNOW OVER THE MOUNTAINS DURING THE AFTERNOON WITH LIGHT ACCUMULATIONS BY THE EVENING. ALONG THE FOOTHILLS...RAINFALL AMOUNTS WILL BE LIGHT...LESS THAN A TENTH OF AN INCH. && .BOU WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 9 PM THURSDAY TO NOON MDT FRIDAY FOR COZ033>035. && $$ SHORT TERM...D-L LONG TERM....DANKERS AVIATION...D-L
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1030 AM MDT WED OCT 16 2013 .UPDATE... && .SHORT TERM...TEMPERATURES HAVE WARMED TO THE LOWER 30S ACROSS THE NORTHEAST PLAINS...THOUGH A FEW LOCATIONS ALONG THE RIVER BOTTOMS STILL AROUND 30. FREEZE WARNING HAS BEEN ALLOWED TO EXPIRE. OTHERWISE...WEAK MID LEVEL DISTURBANCE MOVING ACROSS SOUTHERN COLORADO WITH SOME CLOUDS OVER MOUNTAINS...SOUTHERN FOOTHILLS AND SOUTH PARK. MAIN LIFT ACROSS SOUTHERN COLORADO...VERY LIMITED OVER SOUTHERN SECTIONS OF CFWA. LATEST RUC AND NAM SHOWING A DRIER SUBSIDENT AIRMASS OVER THE AREA BY 18Z AS THE DISTURBANCE MOVES OUT OF COLORADO. WILL LIMIT ANY PRECIPITATION CHANCES FOR THE THE CENTRAL MOUNTAINS AND SOUTH PARK DURING THE MORNING HOURS. WILL ALSO DECREASE THE CLOUDS A BIT...BASED ON CURRENT SATELLITE. REST OF FORECASTS SEEM ON TRACK...WITH WARMER TEMPERATURES EXPECTED TODAY. .AVIATION...CURRENT TAF TRENDS LOOK ON TRACK WITH VFR CONDITIONS PREVAILING. WINDS SHOWING SIGNS OF BECOMING A BIT MORE NORTHWEST... WITH SPEEDS LESS THAN 8 KTS. SHOULD SEE WINDS SHIFTING TO THE NORTHEAST BY 20Z...WITH SPEEDS AROUND 8 KTS. LATEST RAP AND TO A CERTAIN EXTEND THE HRRR INDICATING WINDS BECOMING SOUTHEAST BY 02Z. WITH FLOW ALOFT BECOMING MORE NORTHWEST AND A BIT OF MIXING...WOULD EXPECT WINDS TO HAVE MORE OF A NORTHWEST DIRECTION THROUGH 02Z BEFORE SHIFING TO THE SOUTHWEST. && .PREV DISCUSSION... /ISSUED 253 AM MDT WED OCT 16 2013/ SHORT TERM...SHARPLY TILTED UPPER TROUGH AND LOW CENTER CONTINUE THEIR SLOW EASTWARD PROGRESS ACROSS COLORADO AT THIS TIME. ON SATELLITE IMAGERY...THE MID-LEVEL CIRCULATION APPEARED TO BE CENTERED IMMEDIATELY NORTHEAST OF THE FOUR CORNERS. INCREASING CLOUD ENHANCEMENT SHOWING UP ON IR SAT IMAGERY OVER SOUTH CENTRAL AND SOUTHEAST COLORADO ASSOCIATED WITH WARM ADVECTION/ISENTROPIC LIFT OUT AHEAD OF THE UPPER LOW. AREA OF ENHANCEMENT EXTENDS AS FAR NORTH AS THE PALMER DIVIDE. IN THE PAST HOUR NWS DEN AND PUB RADARS DETECTED A MODEST INCREASE IN PRECIP ECHO COVERAGE ACROSS SOUTHEAST COLORADO. NOW SEE A FEW ECHOS POPPING OVER THE FOOTHILLS IN DOUGLAS COUNTY AND THE SOUTHWEST TIP OF LINCOLN COUNTY. THE STRONGER RADAR RETURNS REMAIN WELL SOUTH OF THE AREA. OVER THE NEXT SEVERAL HOURS NAM...GFS...WRF AND EUROPEAN MODELS ALL SHOW THE UPPER LOW WITH ITS LIFT AND PRECIPITATION FIELDS TRACKING EASTWARD ALONG THE SOUTHEAST COLORADO/NORTHEAST NEW MEXICO BORDER. SOUTHERN PORTIONS OF OUR FORECAST AREA MAY CATCH SOME OF THE NORTHERN EDGE OF THIS SYSTEM IN THE FORM OF A FEW SNOW SHOWERS GENERALLY OF LIGHT INTENSITY. SOUTH PARK AND FOOTHILL AREAS WEST/SOUTHWEST OF DENVER MAY ALSO SEE AN UPTICK IN PRECIP FORMATION IN THE NEXT FEW HOURS. HOWEVER ANY QPF/SNOW ACCUMULATION SHOULD BE MINIMAL IF ANY. HOWEVER ALL BUT THE FAR NORTHEAST CORNER OF THE CWFA WILL LIKELY REMAIN UNDER MOSTLY TO OVERCAST SKIES THROUGH THE EARLY MORNING HOURS...AT LEAST UNTIL THE UPPER LOW MOVES EAST OF THE AREA AND THE 850-600 MB TURNS NORTHWESTERLY. OVERALL..THE FREEZE WARNING OVERNIGHT VERIFIED. AT THE PRESENT TIME...TEMPERATURES ON THE PLAINS IN THE MID TO UPPER 20S ALL EXCEPT IN BOULDER COUNTY WHERE THE LOW CLOUD COVER HAS HELD TEMPERATURES TO THE LOW/MID 30S. WITH ANY CLEARING DURING THE NEXT FEW HOURS...WARNING SHOULD VERIFY THERE...TOO. FOR THE REMAINDER OF TODAY...THE UPPER TROUGH MOVES OUT ALLOWING DRIER AIR TO FILTER DOWN FROM WYOMING RESULTING IN GRADUAL CLEARING FROM NORTH TO SOUTH. RETURN OF SUNSHINE BY AFTERNOON SHOULD RETURN TEMPERATURES TO THE 50S ON THE PLAINS. CLEARING WON/T BE AS QUICK IN THE HIGH COUNTRY SO ONLY SLIGHTLY WARMER UP THERE TODAY. HIGHER ELEVATIONS SHOULD ALSO SEE THE LAST OF THE FEW REMAINING LIGHT SNOW SHOWERS BY LATE MORNING OR EARLY AFTERNOON. FOR THE MOST PART WINDS WILL BE LIGHT TODAY EXCEPT IN THE FAR NORTHEAST WHERE NWLY WINDS OF 10-20KTS EXPECTED TO DEVELOP THIS AFTERNOON WITH INCREASING NORTHWESTERLY FLOW ALOFT ON THE BACK SIDE OF THE TROUGH. OVERNIGHT...A WEAK SHORTWAVE RIDGE EMBEDDED IN NORTHWESTERLY FLOW ALOFT WILL PASS OVERHEAD. CLEAR SKIES...CHILLY TEMPERATURES AND LIGHT WINDS WILL BE THE RULE. ALTHOUGH THE FAR NORTHEAST CORNER MAY CONTINUE TO SEE NORTHWEST WINDS OF 10-15 KTS FOR MUCH OF THE NIGHT IN RESPONSE TO STRENGTHENING NORTHWESTERLY FLOW ALOFT. LONG TERM...FOR MUCH OF THE LONG TERM FORECAST COLORADO WILL BE UNDER A MODERATE NORTHWEST FLOW PATTERN AS HIGH PRESSURE RIDGING ALOFT REMAINS OFF THE WEST COAST. WITHIN THE FLOW...AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS COLORADO THURSDAY NIGHT AND FRIDAY MORNING WITH THE NEXT SHOT OF PRECIP FOR THE AREA. OVER THE PAST FEW RUNS THE MODELS HAVE BECOME VERY CONSISTENT WITH THIS WAVE AND TIMING. HENCE...WITH INCREASING CONFIDENCE WILL CONTINUE THE UPWARD TREND IN CHANCES OF RAIN AND SNOW. AN ASSOCIATED COLD FRONT WILL MOVE INTO NORTHEAST COLORADO THURSDAY AFTERNOON WITH SHALLOW UPSLOPE FLOW DEVELOPING. INITIALLY THE AIRMASS WILL BE DRY BUT EXPECT INCREASING MOISTURE DURING LATE THURSDAY AFTERNOON AND EVENING. APPEARS THERE WILL BE ENOUGH COOLING FOR MOST LOCALES TO SEE SNOW LATE THURSDAY NIGHT AND INTO FRIDAY MORNING AS AIRMASS SATURATES. OVERALL QPF FROM MODELS IS RANGING FROM .10 TO UP TO 50" OF AN INCH SO CONCEIVABLE THAT THE NORTHEAST PLAINS AND MOUNTAINS MAY SEE A COUPLE OF INCHES OF SNOW FROM THIS SYSTEM. THERE IS SOME MODEST QG FORCING ALOFT AS THIS SYSTEM PASSES ACROSS COLORADO. THE SNOW WILL END FROM NORTH TO SOUTH ON FRIDAY MORNING WITH A RETURN TO DRY CONDITIONS FROM LATE FRIDAY THROUGH THE WEEKEND. THERE IS ANOTHER WEAK WAVE THAT BRUSHES NORTHEAST COLORADO SUNDAY NIGHT AND MONDAY BUT FOR NOW MOISTURE LOOKS QUITE LIMITED WITH THIS SYSTEM. WITH THE NORTHWEST FLOW PATTERN A STRONGER JET STREAK WILL APPROACH NORTHEAST COLORADO LATE MONDAY AND TUESDAY WITH SOME MOISTURE. BEING THAT FAR OUT WILL KEEP THINGS DRY FOR NOW. AVIATION...LOW CLOUD CEILINGS IN THE 3000-5000 FT AGL RANGE IN THE DENVER AREA AS OF 09Z/WED. LOWER CEILINGS FOUND IN THE MTNS AND FOOTHILLS. LOW CLOUDS OVER AND NEAR THE FOOTHILLS WEST AND SOUTHWEST OF DENVER PRODUCING SNOW FLURRIES AT THIS TIME. DO NOT EXPECT TO SEE MORE THAN A FEW FLURRIES AT DENVER AREA AIRPORTS NOW THROUGH 15Z THIS MORNING. OTHERWISE CEILINGS IN THE DENVER AREA SHOULD BEGIN LIFTING NOT LONG AFTER SUNRISE (13Z-14Z)...WITH VFR CEILINGS BY MID-MORNING...AND PARTLY CLOUDY SKIES BY MIDDAY. THE OUTLOOK IS FOR VARIABLE WINDS GENERALLY UNDER 10 KTS TODAY. TONIGHT EXPECT TYPICAL DRAINAGE WINDS UNDER 8 KTS UNDERNEATH A CLEAR TO MOSTLY CLEAR SKY. HYDROLOGY...NO CONCERNS AT THIS TIME. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...D-L LONG TERM....ENTREKIN AVIATION...D-L
AREA FORECAST DISCUSSION
NWS MIAMI FL
857 AM EDT WED OCT 16 2013 .UPDATE... DO NOT PLAN TO MAKE ANY MAJOR CHANGES OTHER THAN TO ADD SLIGHT CHANCE OF SHOWERS. THE 12Z MFL SOUNDING CONTINUES TO SHOW VERY DRY ATMOSPHERE IN PLACE WITH PWAT JUST OVER AN INCH AND STRONG SUBSIDENCE CAP WITH THE BASE AT 6-8K FEET. HOWEVER, THERE HAVE BEEN ISOLATED SHOWERS OVER THE ATLANTIC THAT HAVE TEASING THE BROWARD COUNTY COAST WITH AN EFFORT TO MOVE ONSHORE WITH THE DIURNAL HEATING CYCLE BEGINNING TO TAKE SHAPE. THE HRRR ALSO SHOWS A FEW SHOWERS DEVELOPING INLAND LATE THIS AFTERNOON IN THE LOW LEVEL NORTHEAST FLOW. THESE WILL BE VERY LOW TOPPED SO RAINFALL AMOUNTS WILL BE SMALL AREA COVERAGE AND MOSTLY JUST OVER A TRACE ACCUMULATION. OTHERWISE, THE TRANQUIL WEATHER PATTERN CONTINUES. KOB && .PREV DISCUSSION... /ISSUED 218 AM EDT WED OCT 16 2013/ ..CONTINUED MOSTLY DRY WEATHER THROUGH FRIDAY BEFORE A SLIGHT CHANCE OF SHOWERS RETURN OVER SOUTH FLORIDA THIS WEEKEND... SHORT TERM... HIGH PRESSURE OVER THE SOUTHEASTERN UNITED STATES WILL REMAIN NEARLY STATIONARY TODAY THROUGH FRIDAY...AS A WEAK SURFACE TROUGH OVER THE BAHAMA ISLANDS MOVES SLOWLY WEST TO SOUTHWEST INTO THE FLORIDA KEYS. THIS WILL KEEP A NORTHEAST TO EAST WIND OVER SOUTH FLORIDA TODAY INTO FRIDAY ALLOWING FOR A SLOW INCREASE IN MOISTURE OVER THE AREA. THERE COULD BE ONE OR TWO LIGHT SHOWERS THAT AFFECT THE ATLANTIC WATERS AND THE EAST COAST METRO AREAS TODAY INTO FRIDAY...BUT THE SHOWER COVERAGE WILL BE FAR AND FEW. SO WILL KEEP THE WEATHER DRY OVER SOUTH FLORIDA THROUGH THIS TIME AND ONLY SHOW A SLIGHT 10 PERCENT POPS OVER THE AREA. PATCHY FOG IS ALSO POSSIBLE OVER SOUTH FLORIDA LATE TONIGHT AND AGAIN LATE THURSDAY NIGHT WITH EVEN AREAS OF FOG OVER THE INTERIOR PORTIONS...DUE TO THE INCREASE IN LOW LEVEL MOISTURE WORKING INTO THE AREA FROM THE ATLANTIC WATERS. SO HAVE ADDED FOG WORDING TO THE ZONES FOR LATE TONIGHT AND AGAIN LATE THURSDAY NIGHT. LONG TERM... THE HIGH OVER THE SOUTHEASTERN UNITED STATES SHOULD MOVE SLOWLY EAST INTO THE WESTERN ATLANTIC WATERS THIS WEEKEND...AS A COLD FRONT OVER THE THE CENTRAL UNITED STATES MOVES SLOWLY SOUTHEAST INTO THE SOUTHERN GULF COAST STATES. THIS WILL ALLOW FOR THE WIND FLOW TO BECOME MORE EASTERLY OVER SOUTH FLORIDA THIS WEEKEND WHICH IN TURN WILL CONTINUE TO BRING IN LOW LEVEL MOISTURE TO THE AREA. SO WILL CONTINUE THE SLIGHT CHANCE OF SHOWERS OVER SOUTH FLORIDA THIS WEEKEND. THE FRONT WILL THEN BECOME STATIONARY OVER THE SOUTHERN GULF COAST STATES EARLY NEXT WEEK...AS THE HIGH OVER THE WESTERN ATLANTIC WATERS REMAINS NEARLY STATIONARY. THIS WILL KEEP A EAST TO SOUTHEAST WIND FLOW OVER SOUTH FLORIDA ALONG WITH LOW LEVEL MOISTURE. SO WILL CONTINUE THE SLIGHT CHANCE OF SHOWERS OVER THE AREA FOR EARLY NEXT WEEK. MARINE... THE WINDS OVER SOUTH FLORIDA WILL REMAIN IN A NORTHEAST TO EAST DIRECTION WITH SPEEDS OF 10 KNOTS OR LESS TODAY INTO FRIDAY...BEFORE SWINGING TO A EAST TO SOUTHEAST DIRECTION THIS WEEKEND. SO THE SEAS IN THE ATLANTIC WATERS WILL REMAIN AT OR BELOW 4 FEET TODAY INTO THIS WEEKEND...WHILE IN THE GULF WATERS THE SEAS WILL BE 2 FEET OR LESS. SO BOATING CONDITIONS WILL REMAIN GOOD THROUGH THIS WEEKEND OVER BOTH THE ATLANTIC AND GULF WATERS OF SOUTH FLORIDA. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 87 72 87 73 / 10 10 10 10 FORT LAUDERDALE 86 75 87 76 / 10 10 10 10 MIAMI 87 74 88 75 / 10 10 10 10 NAPLES 87 70 88 72 / 10 - 10 - && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS MIAMI FL
1253 AM EDT WED OCT 16 2013 .AVIATION... ALTHOUGH AN AREA OF WEAK LOW PRESSURE CONTINUES ACROSS THE NORTHERN BAHAMAS...SHOWERS ARE EXPECTED TO MAINLY REMAIN IN THE OFF SHORE ATLANTIC WATERS. MAINLY VFR CONDITIONS ARE EXPECTED EARLY THIS MORNING. PATCHY MORNING FOG IS POSSIBLE...BUT MAINLY IN THE INTERIOR. 60 && .PREV DISCUSSION... /ISSUED 1005 PM EDT TUE OCT 15 2013/ UPDATE... THE 00Z SOUNDING INDICATED A STABLE LOCAL ATMOSPHERE WITH A WELL PRONOUNCED LOW LEVEL INVERSION. A WEAK AREA OF LOW PRESSURE ACROSS THE BAHAMAS IS PRODUCING ISOLATED SHOWERS ACROSS THE OFF SHORE ATLANTIC WATERS...BUT UPPER LEVEL SUBSIDENCE ACROSS THE REGION IS SUPPRESSING ANY SUBSTANTIAL DEVELOPMENT OF THE SHOWERS AND MAINLY ISOLATED ACTIVITY IS EXPECTED ACROSS THE ATLANTIC WATERS TONIGHT. NO SIGNIFICANT CHANGES WERE REQUIRED TO THE CURRENT FORECAST PACKAGE. 60 PREV DISCUSSION... /ISSUED 824 PM EDT TUE OCT 15 2013/ AVIATION... LOW PRESSURE ACROSS THE BAHAMAS CONTINUES TO SPREAD MOISTURE WESTWARD AND INTO THE OFFSHORE ATLANTIC WATERS. ASSOCIATED SHRAS ARE EXPECTED TO STAY AWAY FROM THE EAST COAST SITES THROUGH THE NIGHT. LOCAL HI RES MODELS DEPICT A FEW OF THESE SHRAS MOVING CLOSER TO THE EAST COAST SITES DURING THE DAY TOMORROW. KEPT VCSH AFTER 14Z. WINDS SHOULD BE LIGHT OVERNIGHT WITH WEAK DRAINAGE AT KAPF. EAST-NORTHEASTERLY FLOW SHOULD PREVAIL AT THE EAST COAST SITES TOMORROW AT AROUND 10 KTS WITH A GULF BREEZE DEVELOPING AT KAPF. PREV DISCUSSION... /ISSUED 231 PM EDT TUE OCT 15 2013/ SHORT TERM (TONIGHT-THURSDAY NIGHT)... VERY PROGRESSIVE MID LATITUDE PATTERN TAKING SHAPE ACROSS NORTH AMERICA WITH TWO MAJOR MID/UPPER LEVEL TROUGHS MOVING ACROSS THE NORTHERN STATES THIS PERIOD. AT THE SAME TIME, A TROUGH HAS BEEN CUT OFF OVER THE ATLANTIC NORTH OF THE BAHAMAS WITH A RIDGE ACROSS THE GULF OF MEXICO. THE ATLANTIC TROUGH WILL DRIFT SOUTH OVER THE NEXT COUPLE OF DAYS AS A STRONG RIDGE AMPLIFIES OVER THE EASTERN PACIFIC FORCING THE GULF RIDGE TO EXPAND EAST AND THE ATLANTIC TROUGH GETS PINCHED OFF FROM THE NORTHERN STREAM TROUGHS. THE ATLANTIC TROUGH HAS IN TURN, INDUCED A WEAK SURFACE TROUGH ACROSS THE BAHAMAS IN THE VICINITY OF NASSAU AND ANDROS ISLAND. THIS IS CLEARLY EVIDENT ON VISIBLE SATELLITE AND IT APPEARS TO BE DRIFTING TO THE WEST IN AN OTHERWISE WEAK SURFACE PRESSURE PATTERN IN THE AREA SURROUNDING SOUTH FLORIDA. I MENTION ALL OF THIS AS THE NAM HAS CAPTURED THIS SURFACE FEATURE MORE SO THAN THE GFS OR THE ECMWF FOR THAT MATTER. THE PROBLEM FOR AT LEAST THE FIRST PERIOD OR TWO WITH THIS FORECAST PACKAGE IS HOW MUCH AFFECT THIS TROUGH WILL HAVE ON SOUTH FLORIDA. THERE ALREADY ARE SCATTERED SHOWERS OVER THE FAR OFFSHORE ATLANTIC WATERS WITH A COUNTERCLOCKWISE MOVEMENT TO THEM AROUND THE LOWER PRESSURE. HOWEVER, THE NAM IS NOTED FOR SUFFERING FROM MESOSCALE BIAS BUT SOMETIMES PICKS UP ON THESE SMALL SCALE FEATURES WITH ITS FINER RESOLUTION BETTER THAN THE GFS. THE LATEST RUN OF THE HIGH RESOLUTION HRRR ALSO SHOWS AN INCREASE IN SHOWER ACTIVITY APPROACHING THE SOUTHEAST FLORIDA COAST LATER TONIGHT. FOR ALL OF THESE REASONS, WILL INTRODUCE SCATTERED POPS FOR THE THE SOUTHEAST COASTAL REGION FOR LATE TONIGHT AND CONTINUING INTO EARLY WEDNESDAY. IN ADDITION, DUE TO ITS MESOSCALE BIAS WILL NOT GO AS BULLISH AS THE MET GUIDANCE BUT WILL CERTAINLY GO ABOVE THE MAV NUMBERS. THE GULF OF MEXICO RIDGE WILL CONTINUE TO BUILD EAST THROUGH THURSDAY NIGHT WHICH SHOULD MAINTAIN A SUBSIDENCE CAP ACROSS THE REGION. THE NAM CONTINUES HIGH MOISTURE OVER SOUTH FLORIDA THROUGH THURSDAY NIGHT SHOWING PWAT IN THE RANGE OF 1.6-1.9 INCHES. THIS IS NO DOUBT IS OVERDONE CONSIDERING THE RIDGE SHOULD MAINTAIN A SUBSIDENCE CAP OVER SOUTH FLORIDA AND WILL REDUCE THE POPS CLOSER TO THE MAV GUIDANCE BUT AGAIN THE MAV MIGHT BE TOO LOW. ON A SIDE NOTE, THIS IS THE TIME OF THE YEAR OF ASTRONOMICAL HIGH TIDES AND THE HIGHEST TIDES ALONG THE ATLANTIC COAST WILL BE PEAKING BETWEEN THIS EVENING THROUGH THE UPCOMING WEEKEND. THIS ALSO COINCIDES WITH THE FULL MOON WHICH IS TO OCCUR ON FRIDAY. THERE WILL THEREFORE BE AN INCREASE IN SOME NUISANCE TYPE URBAN STREET FLOODING AT TIMES OF HIGH TIDE OVER THE NEXT SEVERAL DAYS POSSIBLY INTO THE EARLY NEXT WEEK ESPECIALLY ON THE BARRIER ISLANDS SUCH AS MIAMI BEACH. THE HIGH TIDES THROUGH THE END OF THIS WEEK WILL BE OCCURRING IN THE EVENING AND AGAIN EARLY IN THE MORNING. LONG TERM (FRIDAY-TUESDAY)... THE GULF RIDGE WILL MAINTAIN A PRESENCE ACROSS SOUTH FLORIDA THROUGH THE EXTENDED PERIOD. FOR THIS REASON, A COLD FRONT THAT WILL MOVE INTO THE SOUTH GULF COASTAL STATES EARLY FRIDAY, WILL STALL AND REMAIN NEARLY STATIONARY THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THIS WILL MAINTAIN A LOW LEVEL EASTERLY FLOW BUT WITH MOISTURE CONTENT REMAINING LOW. BUT STILL, THERE COULD BE SOME ISOLATED SHOWERS ESPECIALLY ALONG THE EAST COAST. MARINE... TRANQUIL WIND AND SEAS WILL CONTINUE THROUGH THE PERIOD WITH SEAS 4 FEET OR LESS. THERE COULD BE AN INCREASE IN SHOWER ACTIVITY OVER THE ATLANTIC WATERS THIS EVENING SPREADING TOWARDS THE SOUTHEAST COAST INCLUDING BISCAYNE BAY AFTER MIDNIGHT DUE TO AN APPROACHING SURFACE TROUGH. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 87 73 87 74 / 20 20 10 10 FORT LAUDERDALE 85 74 85 75 / 20 20 20 10 MIAMI 86 75 87 75 / 20 20 20 10 NAPLES 88 72 88 72 / 20 10 20 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ DISCUSSION/MARINE/FIRE...54/BNB AVIATION/RADAR...60/BD
AREA FORECAST DISCUSSION...UPDATE
NWS PEACHTREE CITY GA
731 PM EDT THU OCT 17 2013 .EVENING UPDATE... THE COLD FRONT HAS JUST PUSHED SOUTH OF ATLANTA WITH PATCHY SHOWERS...LIGHT RAIN AND DRIZZLE ALONG AND AHEAD OF THE FRONT... NOW MOSTLY ACROSS CENTRAL GA. NOT SUFFICIENT LIFT NOR INSTABILITY TO WARRANT MENTION OF THUNDER THE REST OF TONIGHT... SO HAVE UPDATED ZONES TO REMOVE THUNDER WORDING. CLOUDS STRETCH WELL BACK INTO TN AND NW AL... SO HAVE TWEAKED CLOUDS TO SHOW A SLOW SCATTERING OVER NORTH GA THIS EVENING AND OVERNIGHT... THEN HELD ONTO MOSTLY CLOUDY SKIES ACROSS MUCH OF CENTRAL GA THROUGH TONIGHT. ADJUSTED POPS TO BETTER ALIGN WITH RADAR TRENDS. OTHERWISE... FORECAST IS ON TRACK WITH SCATTERED SKIES AND COOLER LOWS IN THE 40S STILL EXPECTED TO SPREAD INTO NORTH GA BY MORNING. /39 .SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/... /ISSUED AT 344 PM EDT THU OCT 17 2013/ SHORT TERM MODELS IN FAIRLY GOOD AGREEMENT...SHOWING WEAKEN FRONT WASHING OUT AS IT MOVES ACROSS THE FORECAST AREA THIS AFTERNOON AND EVENING. LATEST RAP HAS INITIALIZED AREA OF SHOWERS WELL AND NEAR TERM FORECAST WILL LEAN HEAVILY TOWARD RAP AS SHOWERS DISSIPATE IN THE ATL AREA BY 4-5PM AND OVER THE GVL-AHN AREA BY THIS EVENING. WILL GO AHEAD AND DROP MENTION OF THUNDER FROM FORECAST AS INSTABILITY LIMITED AS WEAK WAVES MOVES ACROSS THE AREA THIS AFTERNOON AND EVENING AND THE SHOWER ACTIVITY IS PUSHING OUT OF FORECAST AREA AS THE SHORTWAVE APPROACHES. MODELS BRINGING DRIER AIR INTO THE AREA THIS EVENING WITH CLEARING SKIES BY MORNING. LATEST SATELLITE SHOWING CLOUDS CONTINUE BACK INTO PORTIONS OF MISSISSIPPI AND EXPECT THAT WHILE THERE WILL BE DRYING WE CAN ALSO EXPECT SOME COOL AREA STRATUS TO DEVELOP AS WELL. WILL COMPROMISE FOR NOW AND SETTLED ON SCATTERING CLOUDS OUT THIS EVENING BUT DID NOT CLEAR THEM OUT ALTOGETHER. BASED UPON HOLDING SOME CLOUDS IN HAVE GONE WARMER THAN GUIDANCE TEMPERATURES BY A DEGREE OR SO OVERNIGHT WITH HIGHS TOMORROW SLIGHTLY WARMER THAN TODAY. ATWELL .LONG TERM /SATURDAY THROUGH THURSDAY/... /ISSUED AT 344 PM EDT THU OCT 17 2013/ NO MAJOR CHANGES MADE TO THE EXTENDED FORECAST. MODELS CONSISTENT INDICATING THE COLD FRONT WITH BE SE OF THE FORECAST AREA TO START FRIDAY NIGHT. HOWEVER GFS/NAM/EUROPEAN SOMEWHAT DIFFERENT WITH THE PLACEMENT OF THE DEEPER MOISTURE AXIS THROUGH THE NIGHT. GFS/NAM SIMILAR WITH SPREADING DEEPER MOISTURE BACK OVER MAINLY CENTRAL GA AND THE EUROPEAN IS MORE BROADLY SPREADING MOISTURE ACROSS THE ENTIRE AREA BY NIGHTS END. ALL IN ALL THIS SEEMS TO KEEP BEST SHOWER CHANCES ACROSS MAINLY CENTRAL GA. GFS/NAM KEEPS THE BEST MOISTURE AND SHOWER CHANCES ACROSS CENTRAL GA FOR SATURDAY WHILE THE EUROPEAN SPREADS MOISTURE AND SHOWER CHANCES ACROSS THE ENTIRE AREA. EITHER WAY THE BEST CHANCES FOR SHOWERS WILL BE ACROSS CENTRAL GA AND POSSIBLY PORTIONS OF N GA. THE MOISTURE COMING N DUE MAINLY TO THE APPROACH OF A SHORT WAVE. THE MOISTURE WILL HAVE EXITED ALL BUT THE FAR SE CWA TO START SUNDAY BUT WILL EXIT THAT AREA QUICKLY. SURFACE HIGH PRESSURE MOVES INTO THE ATLANTIC ON MONDAY WHICH BEGINS TO SPREAD MOISTURE INTO THE FAR SE CWA WITH SMALL SHOWER CHANCES ASSOCIATED. A WEAK COLD FRONT MOVES TO THE AREA ON TUESDAY WITH INCREASED SHOWER CHANCES ACROSS THE AREA TUESDAY/TUESDAY NIGHT. SMALL SHOWER CHANCES WILL BE CONFINED TO THE FAR SE CWA TO START THE DAY ON WEDNESDAY BEFORE ENDING. TEMPERATURES WILL BE TRENDING TO A LITTLE BELOW NORMAL FOR MUCH OF THE EXTENDED PERIOD. BDL/01 01 && .AVIATION... 00Z UPDATE... SURFACE MAP SHOWS THE COLD FRONT PUSHING SOUTH OF ATL AT THIS TIME. SATELLITE IMAGERY AND REGIONAL OBS SHOW MVFR CIGS STRETCHING BACK INTO NORTH AL AND CENTRAL TN. WILL HOLD ONTO MVFR CIGS THROUGH 03Z FRI...THEN CLOUDS MIGHT SCATTER BY 05-06Z FRI... BUT CONFIDENCE IN ONLY MEDIUM ON THIS. WORSE CASE... MID LEVEL CIGS COULD PERSIST THRU 08-09Z FRI. OTHERWISE...ONCE SCATTER... MAINLY A WIND FORECAST. A NW WIND AROUND 5-8KTS WILL PERSIST THRU 19-20Z FRI...THEN WINDS BACK MORE WEST AS A MID LEVEL DISTURBANCE PUSHES ACROSS THE STATE. A NW WIND WILL RETURN BY 00-02Z SAT AND PERSIST SAT NIGHT AT 4-6KTS. //ATL CONFIDENCE...00Z UPDATE... MEDIUM TO HIGH CONFIDENCE ALL ELEMENTS. 39 && .PRELIMINARY POINT TEMPS/POPS... ATHENS 55 74 55 72 / 40 5 20 20 ATLANTA 56 73 59 71 / 40 5 10 20 BLAIRSVILLE 44 68 48 72 / 40 5 5 10 CARTERSVILLE 49 72 52 75 / 30 5 5 10 COLUMBUS 61 79 61 74 / 20 10 30 30 GAINESVILLE 53 69 56 74 / 40 5 5 20 MACON 59 77 61 74 / 20 10 40 30 ROME 49 73 50 75 / 10 5 5 10 PEACHTREE CITY 54 73 54 72 / 40 5 10 20 VIDALIA 65 82 65 77 / 10 30 50 30 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...ATWELL/39 LONG TERM....01 AVIATION...39
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
351 PM EDT WED OCT 16 2013 ...SHALLOW COASTAL FLOODING LIKELY AROUND HIGH TIDE THIS EVENING... ...COASTAL FLOOD ADVISORY IN EFFECT FROM 5 PM UNTIL 10 PM EDT... .SYNOPSIS... WEAK HIGH PRESSURE WILL PREVAIL OVER THE REGION TONIGHT. A COLD FRONT WILL MOVE INTO THE AREA EARLY FRIDAY...THEN STALL ALONG THE SOUTHEAST COAST THROUGH SATURDAY. THE FRONT WILL PUSH OFFSHORE ON SUNDAY...AS HIGH PRESSURE BUILDS FROM THE NORTHWEST AND PREVAILS INTO EARLY NEXT WEEK. A WAVE OF LOW PRESSURE COULD APPROACH FROM THE SOUTHWEST DURING THE MIDDLE OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... WEAK HIGH PRESSURE WILL HOLD FIRM ACROSS THE REGION TONIGHT. THE SHALLOW CUMULUS FIELD THAT HAS DEVELOPED THIS AFTERNOON WILL QUICKLY DISSIPATE THIS EVENING WITH THE LOSS OF INSOLATION. HOWEVER...A THICK MID/HIGH-LEVEL CLOUD DECK ASSOCIATED WITH AN APPROACHING COLD FRONT WILL BEGIN TO AFFECT THE FAR WESTERN ZONES EARLY THIS EVENING...SPREADING STEADILY EAST TO THE COAST. SHOULD SEE MOSTLY CLOUDY IF NOT CLOUDY SKIES DOMINATE FROM LATE EVENING ON. THE INCREASED CLOUD COVER WILL PROMOTE WARMER OVERNIGHT LOWS...RANGING FROM THE LOWER 60S INLAND TO THE MID/UPPER 60S AT THE BEACHES. SREF VISIBILITY PLUMES AND RAP BUFR SOUNDINGS SUGGEST SOME SHALLOW GROUND FOG COULD AFFECT AREAS ROUGHLY ALONG AND EAST OF I-95 EARLY THURSDAY...BUT DO NOT ANTICIPATE IT WILL BECOME TOO MUCH OF AN ISSUE GIVEN THE THICK MID/HIGH-LEVEL CLOUDS THAT WILL BE IN PLACE. WILL CONTINUE TO HIGHLIGHT PATCHY FOG IN THE TEXT AND GRIDDED FORECASTS TO ACCOUNT FOR SOME SMALL REDUCTIONS IN VISIBILITIES EARLY THURSDAY. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... THURSDAY...THE AXIS OF RIDGING AT THE SURFACE AND ALOFT WILL HAVE SHIFTED OFFSHORE BY THURSDAY MORNING...WHILE AN UPPER SHORTWAVE SWEEPS NORTHEAST INTO THE GREAT LAKES DURING THE DAYTIME HOURS. THIS TRANSITION WILL ALLOW A COLD FRONT TO SHIFT TOWARD THE APPALACHIAN REGION...AND A PRE-FRONTAL TROUGH TO MOVE INTO THE WESTERN CAROLINAS...BY LATE AFTERNOON/EARLY EVENING. THE SURFACE TROUGH WILL THEN STEADILY DESCEND INTO THE FORECAST AREA OVERNIGHT...AS THE PROGRESS OF THE MAIN FRONT SLOWS UPSTREAM DUE TO DAMPENING SHORTWAVE ENERGY DEPARTING WELL TO THE NORTH. NUMERICAL MODEL SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT THAT ANY PRECIPITATION WILL REMAIN JUST TO THE WEST OF THE FORECAST AREA THROUGH AT LEAST THE DAYTIME HOURS. CONVERGENCE ASSOCIATED WITH THE APPROACHING PRE-FRONTAL TROUGH THEN SUPPORTS A SLIGHT CHANCE FOR SHOWERS ALONG THE FAR INLAND ZONES AFTER SUNSET AND OVER THE WATERS AFTER MIDNIGHT. TEMPERATURES WILL BE 5 TO 10 DEGREES ABOVE SEASONAL NORMALS AS A RESULT OF WARM WEST/SOUTHWEST FLOW AND COMPRESSIONAL HEATING AHEAD OF THE COLD FRONT. EXPECT HIGH TEMPERATURES TO RANGE IN THE LOW TO MID 80S...WITH MILD LOWS IN THE MID TO UPPER 60S. FRIDAY...AS THE APPROACHING COLD FRONT BECOMES PARALLEL TO THE FLOW ALOFT...AT THE SAME TIME THAT WEAK WAVES OF LOW PRESSURE DEVELOP ALONG THE SURFACE TROUGH...THE FRONT WILL STALL OVER THE AREA AT LEAST THROUGH FRIDAY EVENING. ALTHOUGH UPPER LEVEL SUPPORT WILL STILL REMAIN UNIMPRESSIVE...THERE COULD BE ENOUGH CONVERGENCE AND LIFT ALONG THE FRONTAL ZONES AND WITHIN A POSSIBLE SEABREEZE BOUNDARY TO SUPPORT RAIN CHANCES IN THE 20 PERCENT RANGE DURING THE DAYTIME HOURS. THE 12Z GFS SOLUTION SUGGESTS WEAK SHORTWAVE ENERGY COULD SHIFT INTO THE AREA WITHIN THE BROAD UPPER TROUGH...INCREASING RAIN CHANCES TO AROUND 30 PERCENT ALONG THE COAST AND OVER THE MARINE ZONES FRIDAY NIGHT. TEMPERATURES WILL BE SOMEWHAT DEPENDENT ON THE EXACT LOCATION OF THE STALLED FRONT...YET LATEST THINKING IS THAT BOTH HIGHS AND LOWS WILL BE AT LEAST A FEW DEGREES COOLER...PEAKING IN THE UPPER 70S TO LOWER 80S AND FALLING MAINLY INTO THE LOW TO MID 60S OVERNIGHT. SATURDAY...ADDITIONAL WEAK SHORTWAVE ENERGY WILL STREAM NORTHEAST WITHIN THE BROAD CYCLONIC FLOW ALOFT...AND WHILE THE FRONT BEGINS TO SHIFT TOWARD THE NEARSHORE WATERS AS THE DAY PROGRESSES...EXPECT SUFFICIENT MOISTURE AND CONVERGENCE FOR SCATTERED SHOWERS TO DEVELOP. THICK CLOUD COVER AND THE GRADUAL PROGRESSION OF THE FRONT THROUGH THE REGION WILL KEEP HIGH TEMPERATURES AROUND SEASONAL NORMALS IN THE UPPER 70S FOR SATURDAY AFTERNOON. && .LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/... IT LOOKS LIKE THE COLD FRONT WILL BE FORCED EAST AND SE INTO THE ATLANTIC FOR EARLY NEXT WEEK AS HIGH PRESSURE BUILDS EAST OUT OF THE CENTRAL AND EASTERN PARTS OF THE COUNTRY. BUT THE BAROCLINIC ZONE WILL BEGIN TO WORK ITS WAY BACK NORTH BY THE MIDDLE OF THE WEEK AS A SOUTHERN STREAM SHORT WAVE AND ITS CO-LOCATED SURFACE WAVE LIFTS INTO THE SE PART OF THE COUNTRY. BUT WHEN THIS OCCURS AND EXACTLY WHERE THE TRACK OF THE SURFACE LOW OCCURS REMAINS TO BE SEEN THIS FAR IN ADVANCE. RAIN CHANCES WILL DIMINISH LATER SUNDAY INTO MONDAY...BUT COULD START TO CLIMB AGAIN IN ADVANCE OF THE NEXT SYSTEM TUESDAY AND/OR WEDNESDAY. ADJUSTMENTS WILL LIKELY BE REQUIRED IN SUBSEQUENT FORECASTS. TEMPS WILL BE A BIT COOLER INTO EARLY IN THE WEEK...BUT COULD MODERATE AGAIN BY MID WEEK. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... VFR FOR THE NEXT 24 HOURS. MVFR CIGS AT KCHS WILL LIKELY HOLD ON THROUGH ABOUT 20-21Z BEFORE BREAKING AS THEY ERODE FROM THE WEST. LIGHT/SHALLOW GROUND FOG IS POSSIBLE AT EITHER TERMINAL...BUT ANY SIGNIFICANT IMPACTS SEEM LOW AT THIS POINT. EXTENDED AVIATION OUTLOOK..MVFR CONDITIONS ARE POSSIBLE AT TIMES INTO THE WEEKEND AS A FRONT STALLS OVER THE AREA. && .MARINE... TONIGHT...EAST/NORTHEAST WINDS WILL GO VARIABLE LESS THAN 5 KT ALL LEGS TONIGHT AS WEAK HIGH PRESSURE HOLD FIRM. SEAS WILL RANGE FROM 1-2 FT NEARSHORE WATERS...2-3 FT OFFSHORE WATERS AND BE COMPRISED MAINLY OF EASTERLY SWELL WITH PERIODS OF 10-11 SECONDS. THURSDAY THROUGH MONDAY...HIGH PRESSURE WILL DIMINISH AHEAD OF AN APPROACHING COLD FRONT THURSDAY AND FRIDAY. THE FRONT EVENTUALLY STALLS NEAR THE AREA THROUGH SATURDAY...BEFORE SLIDING EAST/SOUTHEAST OF THE MARINE AREA SUNDAY INTO MONDAY. CONTINENTAL HIGH PRESSURE THEN BUILDS OVER THE SOUTHEAST STATES AND EVENTUALLY INTO THE WESTERN ATLANTIC. WINDS THROUGH THE FORECAST PERIOD WILL BE CAPPED AT 15 KT OR LESS...WITH SEAS NO HIGHER THAN 2 OR 3 FT. THE BEST CHANCE FOR SHOWERS AND POSSIBLE THUNDERSTORMS WILL BE FRIDAY INTO SUNDAY. && .TIDES/COASTAL FLOODING... ISSUED ANOTHER COASTAL FLOOD ADVISORY FOR ALL COASTAL ZONES... INCLUDING TIDAL BERKELEY...VALID 5-10 PM. TIDE IN THE CHARLESTON HARBOR IS EXPECTED TO PEAK 7.2-7.5 FT MLLW AND 9.1-9.4 FT MLLW AT FORT PULASKI. ASTRONOMICAL HIGH TIDES COURTESY OF THE FULL MOON THAT OCCURS FRIDAY EVENING WILL MOST PROBABLY GENERATE ADDITIONAL SHALLOW COASTAL FLOODING WITH MOST IF NOT ALL HIGH TIDES INTO THE WEEKEND. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...COASTAL FLOOD ADVISORY UNTIL 10 PM EDT THIS EVENING FOR GAZ117- 119-139-141. SC...COASTAL FLOOD ADVISORY UNTIL 10 PM EDT THIS EVENING FOR SCZ048>052. MARINE...NONE. && $$ ST/WMS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
142 PM CDT WED OCT 16 2013 .DISCUSSION... 306 AM CDT COOL AND PERIODICALLY DAMP WEATHER WILL DESCRIBE THE FORECAST PERIOD AS AN AMPLIFIED AND ACTIVE PATTERN SETS UP. WATER VAPOR SATELLITE IMAGERY SHOWS A LONGWAVE TROUGH THAT EXTENDS FROM JAMES BAY BACK ACROSS THE CENTRAL PLAINS TO THE FOUR CORNERS. A LARGE NORTH-SOUTH RIDGE IS IN PLACE OFF THE WEST COAST WHILE A MORE PROGRESSIVE FLOW IS FOUND OVER CENTRAL CANADA WHERE ANOTHER TROUGH AXIS IS TRANSLATING SOUTHEASTWARD. AT THE SURFACE...A LOW IS MOVING NORTHEAST ACROSS FAR NORTHERN LAKE MICHIGAN WHICH WAS RESPONSIBLE FOR PUSHING A COLD FRONT ACROSS THE AREA LAST EVENING. A RIBBON OF HIGH PRESSURE STRETCHES FROM THE PACIFIC NORTHWEST TO THE CENTRAL HIGH PLAINS. TODAY...MANY CONCERNS THIS PERIOD RANGING FROM CLOUDS AND STRATUS TO DRIZZLE. THE UPPER TROUGH EXTENDING FROM JAMES BAY SOUTHWEST HAS A CLOSED CIRCULATION EMBEDDED WITHIN IT OVER CENTRAL WISCONSIN. THIS CLOSED CIRCULATION IS EXPECTED TO OPEN UP/WEAKEN WITH THE MAIN LONGWAVE TROUGH PIVOTING ACROSS THE AREA TODAY. IR SATELLITE SHOWS A VERY LARGE AREA OF STRATUS SPREADING EASTWARD ACROSS THE LOCAL AREA. WITH THE UPPER LOW WEAKENING AS IT ARRIVES...UPWARD MOTION WILL BE DIMINISHING THROUGH THE MORNING AND HAVE SEEN THIS ALREADY OCCURRING TO THE NORTH WHERE SHOWER COVERAGE/INTENSITY HAS BEEN WANING. WITH THE EXTENSIVE STRATUS IN PLACE SURFACE WARMING WILL BE LIMITED LEAVING LOW AND MID LEVEL LAPSE RATES MEAGER. WITH THIS IN MIND EXPECT THAT THE FOCUS FOR SHOWERS WILL REMAIN NORTH OF THE AREA LEADING TO LOWER/MINIMAL POPS ACROSS NORTHERN SECTIONS OF THE LOCAL AREA. WILL GO AHEAD AND ADD DRIZZLE ACROSS NORTHERN AREAS THROUGH THE MORNING HOWEVER WITH A DECENT DEPTH OF MOISTURE AND SOME WEAK ASCENT. UPSTREAM OBS OVER THE PAST SEVERAL HOURS HAVE ALSO SHOWN A FAIR AMOUNT OF DRIZZLE. AS ALLUDED TO...THE STRATUS WILL MAKE TEMPS A CHALLENGE. STRATUS DOES LOOK TO HOLD ON THROUGH THE AFTERNOON AND WILL COMBINE WITH LOW LEVEL COLD ADVECTION TO REALLY LIMIT WARMING. UNLESS SOME BREAKS CAN DEVELOP LATE IN THE DAY ALLOWING SOME MINIMAL SUNSHINE...DO NOT EXPECT MORE THAN ABOUT A 3-5 DEGREE DIURNAL INCREASE IN TEMPS FROM MORNING LOW...QUITE A BIT COOLER THAN MOST GUIDANCE. WILL THEREFORE KEEP HIGHS IN THE LOWER 50S IN NORTHERN AREAS TO THE MID EVEN UPPER 50S FAR SOUTH...WITH A BETTER CHANCE FOR SOME SUNSHINE OVER THE EXTREME SOUTHERN PORTIONS OF THE AREA. TONIGHT THROUGH THURSDAY...ATTENTION TURNS TO THE BASE OF THE LONGWAVE UPPER TROUGH OVER THE FOUR CORNERS WHERE ANOTHER CLOSED CIRCULATION IS TAKING SHAPE. THIS LOW WILL EJECT NORTHEASTWARD AND ACROSS THE AREA THURSDAY MORNING. THIS WILL BRING ANOTHER ROUND OF SHOWERS TO MUCH OF THE AREA...ESPECIALLY THE SOUTHEAST TWO-THIRDS... STARTING LATE TONIGHT AND CONTINUING THURSDAY MORNING. TEMPS TONIGHT WILL BE DEPENDENT ON CLOUD COVER. THE LOW CLOUDS LOOK TO HANG ON THROUGH THE EVENING IF NOT THROUGH THE NIGHT. MID CLOUDS WILL BE INCREASING AHEAD OF THE APPROACHING TROUGH OVERNIGHT. WITH SOME QUESTION ABOUT HOW LONG THE LOW CLOUDS WILL HANG ON AND IF THERE WILL BE A BREAK IN CLOUD COVER BEFORE THE HIGHER CLOUDS ARRIVE WILL ONLY RAISE OVERNIGHT LOWS A FEW DEGREES IN MOST AREAS FOR NOW...WITH POTENTIAL FOR ONLY A RELATIVELY SMALL FALL OVER DAYTIME HIGHS. THE PASSAGE OF THE UPPER LOW WILL ALLOW CLOUDS TO DECREASE THURSDAY AFTERNOON WHICH SHOULD ALLOW HIGHS TO WARM SEVERAL DEGREES OVER TODAY DESPITE SIMILAR MID LEVEL TEMPS. FRIDAY THROUGH TUESDAY...THE NEXT FEATURE OF INTEREST IS THE TROUGH MOVING SOUTHEAST ACROSS THE CANADIAN ROCKIES THIS MORNING. PART OF THIS WAVE LOOKS TO SPLIT OFF AND MOVE DUE SOUTH INTO THE CENTRAL ROCKIES WHILE THE REST TRACKS SOUTHEAST ACROSS THE NORTHERN PLAINS AND UPPER MISSISSIPPI RIVER VALLEY. ALL OF THIS ENERGY WILL RESULT IN A NEW LONGWAVE TROUGH RIGHT ACROSS THE MID SECTION OF THE COUNTRY. A WAVE WILL THEN ZIP NORTHEAST ACROSS THE AREA FRIDAY EVENING/NIGHT BRINGING A LOW CHANCE FOR POPS ACROSS THE AREA...ESPECIALLY SOUTHEAST. THE LONGWAVE WILL SHIFT EASTWARD SATURDAY INTO SUNDAY WHICH WILL ALLOW EVEN COLDER MID LEVEL AIR TO SPREAD INTO THE AREA...WITH H85 TEMPS FALLING BELOW 0C. PRECIP CHANCES LOOK LESS COHERENT BUT OVERALL MINIMAL SATURDAY AND SUNDAY...THOUGH LAKE EFFECT SHOWERS LOOK TO BE IN FULL SWING EAST OF LAKE MICHIGAN. HIGHS WILL BE IN THE 50S SATURDAY AND SUNDAY. ADDITIONAL ENERGY WILL TRACK SOUTHEAST ACROSS CENTRAL CANADA INTO THE UPPER MIDWEST AND WESTERN GREAT LAKES LATER SUNDAY THROUGH TUESDAY. THIS WILL LEAD TO ADDITIONAL PRECIP CHANCES AND CONTINUED COOL TEMPERATURES BUT THE DETAILS ARE UNCLEAR AT THIS RANGE. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * LOWER END MVFR STRATUS DECK. * POTENTIAL FOR PATCHY DRIZZLE THROUGH THIS AFTERNOON. * CHANCE OF SHOWERS TOMORROW MORNING. KREIN //DISCUSSION...UPDATED 18Z... MAIN ISSUE FOR THE REMAINDER OF THE AFTERNOON AND THROUGH MUCH OF THE NIGHT WILL CONTINUE TO BE CIGS. LATEST SATELLITE IMAGERY INDICATES A WIDESPREAD AREA OF STRATUS UNDER AN UPPER TROUGH...IN THE WAKE OF AN EXITING UPPER LOW MOVING OFF TO THE NORTHEAST. WHILE THERE ARE A FEW ISOLD AREAS OF IFR CIGS...THE GREATER PORTION OF THE ST DECK IS AT THE LOWER END OF MVFR. WHILE THERE IS A CHANCE FOR SOME IFR CIGS TO SNEAK INTO THE TERMINALS...RFD WOULD BE THE MOST LIKELY LOCATION AND ONLY FOR A BRIEF TIME AS THE UPPER TROUGH AXIS IS OVERHEAD. OTHERWISE...EXPECT A SLOW RECOVERY OF CIGS...AND DO NOT ANTICIPATE IMPROVEMENT TO VFR UNTIL TOMORROW MORNING. SINCE THE SATURATED LAYER IS RELATIVELY SHALLOW...THERE WILL STILL BE A CHANCE FOR SOME SCT SPRINKLES OR DRIZZLE THROUGH THE AFTERNOON AND INTO THE EVENING...BUT DO NOT ANTICIPATE A PREVAILING PCPN CONDITION OR SGFNT REDUCTION IN VIS DUE TO PCPN...OR BR AS DEWPOINTS WILL TREND LOWER THROUGH THE PERIOD AS WELL. THERE WILL BE ANOTHER CHANCE FOR SOME SHOWERS TOMORROW AS ANOTHER UPPER LEVEL WAVES TRACKS ACROSS THE MIDWEST...BUT THE LATEST GUIDANCE SUGGESTS THAT THE TRACK OF THIS FEATURE WILL BE CLOSER TO CNTRL IL/NRN INDIANA. THIS WOULD SUGGEST THAT THE GREATEST CHANCES FOR PCPN WILL BE SOUTH AND EAST OF THE TERMINALS...SO WILL ONLY INCLUDE A VCSH MENTION FOR PCPN AT THIS TIME. KREIN //ORD AND MDW CONFIDENCE...UPDATED 18Z... * HIGH CONFIDENCE IN MVFR CIGS THROUGH THE REST OF THIS AFTERNOON AND THROUGH TONIGHT. CHANCES THAT CIGS WILL DROP TO IFR ARE LOW...BUT NOT TOTALLY OUT OF THE QUESTION...ESPECIALLY THIS AFTERNOON. * MODERATE CONFIDENCE IN TIMING OF CIGS IMPROVING TO VFR TOMORROW MORNING. * MODERATE CONFIDENCE THAT THERE WILL BE LITTLE OR NO IMPACT FROM PCPN ON THE TERMINALS. KREIN //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... THURSDAY NIGHT...VFR. FRIDAY...VFR. SATURDAY...SLT CHC SHRA. SUNDAY...VFR. MONDAY...CHC SHRA. TUESDAY...SLT CHC SHRA. BMD && .MARINE... 124 PM CDT A SERIES OF WEAK LOW PRESSURE SYSTEMS WILL TRAVERSE THE LAKES THIS AFTERNOON THROUGH SUNDAY. A BRIEF HIGH PRESSURE RIDGE WILL THEN BUILD IN SUNDAY AFTERNOON AND EVENING BEFORE ANOTHER LOW MOVES IN MONDAY. GENERALLY WESTERLY FLOW WILL PREVAIL THROUGH THE PERIOD. WINDS GUSTING TO 25 KTS THIS AFTERNOON WILL BE DIMINISHING OVERNIGHT. WITH THE GUSTY WEST WINDS AND WAVES AROUND 4 FT AT MICHIGAN CITY THIS AFTERNOON...WILL CONTINUE WITH THE SMALL CRAFT ADVISORY FOR INDIANA SHORES EAST OF BURNS HARBOR INTO THE EVENING. WINDS WILL RAMP UP AGAIN SATURDAY INTO SUNDAY MORNING...GUSTING TO 25 TO 30 KTS...ESPECIALLY OVER THE SOUTH HALF OF THE LAKE. AN UPPER LOW MOVING OVER THE NORTH PART OF THE LAKE THURSDAY AFTERNOON AND MARGINALLY COLD TEMPERATURES ALOFT WILL PRODUCE A LOW END THREAT FOR A WATERSPOUT. ALLSOPP && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE BURNS HARBOR TO MICHIGAN CITY IN UNTIL 10 PM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1259 PM CDT Wed Oct 16 2013 .DISCUSSION... ISSUED 1045 AM CDT Wed Oct 16 2013 Will be updating the forecast for cooler highs today (mid 50s IL river valley and lower 60s southeast IL) and increase cloud cover, similar to what we did yesterday. Otherwise rest of forecast looks on track today with breezy west winds of 10 to 20 mph and gusts of 20 to 25 mph. 1002 mb low pressure was over the eastern end of upper mi penisula with its cold front slicing through western Ohio and central KY and west TN while a secondary frontal trof was over central WI into southeast IA. Strong 550 dm 500 mb low was ne of Lake Superior with a large upper level trof extending sw into IA/NE and southern CO and northern NM where a short wave was. Low clouds over much of central and nw IL as far southeast as Mattoon and also mid level cloud deck southeast of I-70. Models show upper level trof pivoting se toward central IL and moving into the state on Thursday as short wave ejects from southern CO/northern NM toward the region. This should keep more clouds over central and nw parts of CWA while some sunshine over southeast IL allows for milder highs in the lower 60s. Temps currently in the lower 50s with Bloomington and Galesburg still at 49F. 07 && .AVIATION... ISSUED 1257 PM CDT Wed Oct 16 2013 MVFR ceilings of 1.5-3k feet (currently as far se as MTO) will occur across the central IL terminal airports through tonight and scatter out from west to east after 15Z/Thu. Cloud deck is 1-2k ft thick and will have breaks in it at times like currently at BMI. Have VCSH moving in from 08Z- 10Z from west to east and ending from 15-18Z due to a short wave in the 4 corners ejecting northeast to near St Louis by 12Z Thu and passing ne of central IL by 18Z Thu. VFR visibilies are expected to prevail next 24 hours. Breezy west winds of 10-15 kts with gusts 17-22 kts this afternoon to become light sw this evening and veer more westerly and increaing to 9-13 kts after 15Z Thu. 07 && .PREV DISCUSSION... ISSUED 243 AM CDT Wed Oct 16 2013 Latest surface map shows low pressure over the eastern part of the Michigan Upper Peninsula. The cold front extends southwest, and shows up as a narrow fine line through extreme southwest Indiana per radar imagery from the Evansville radar. Narrow clear slot just west of the Illinois River was about to be overtaken by a large stratocumulus deck from the northwest, and excessive mid and high clouds have been streaming northeast along the front across most of the forecast area. Main concern in the short term is with trying to time any cloud breakup today, followed by rain chances late tonight and early Thursday. Longer range issues focus on early weekend storm system and the cool weather trend which will last much of the forecast period. SHORT TERM...Today through Thursday... Latest RAP model guidance showing the mid/high clouds shifting south toward the Ohio Valley later today, as the stratocumulus pushes south of the I-72 corridor, although the NAM shows some decent break up by late morning. Given the expansive nature of the clouds, stretching all the way into northern Minnesota, will go with the more pessimistic route and keep skies mostly cloudy across the central and northern CWA today, with a bit of sunshine over the south. Went a couple degrees below the MOS guidance for highs, but this may need to be adjusted downward later if we are unable to get any breaks to develop. Shortwave currently near the 4 Corners region will zip eastward later today. 00Z model guidance closes this off as it reaches the Iowa/Illinois border toward sunrise Thursday, but ranges quite a bit in terms of any precipitation over our area. NAM is nearly dry with most of the precip near the remains of the earlier frontal boundary south of the Ohio River, while the GFS has a narrow rain axis just east of I-55. The ECMWF and Canadian models are much more bullish with widespread showers. Currently leaning toward more of the GFS solution but a bit more widespread with the showers Thursday morning, fairly similar in coverage to the earlier grids. However, am thinking that much of this will be out of the area by early afternoon, although some slight chance PoP`s will be in the afternoon forecast across the east. LONG TERM...Friday through Tuesday... A deepening upper trough over the central U.S. will be the main player this weekend, as a wedge of colder air drops southward from Canada. Some potential exists for light rain Friday night or early Saturday as the trough axis starts to shift eastward, but will maintain 20% PoP`s at this time. Some frost potential for Saturday night as winds lighten and temperatures fall into the upper 30s over the northern half of the CWA. Going into early next week, periodic lobes of energy will drop southward across the Midwest. The latest ECMWF remains quite chilly similar to the past couple runs, with 850 mb temperatures falling to around -5C by midweek, although the GFS is several degrees warmer. For now, have not strayed too far from the guidance, which keeps temperatures fairly similar throughout the period. Geelhart && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1101 AM CDT WED OCT 16 2013 .DISCUSSION... 306 AM CDT COOL AND PERIODICALLY DAMP WEATHER WILL DESCRIBE THE FORECAST PERIOD AS AN AMPLIFIED AND ACTIVE PATTERN SETS UP. WATER VAPOR SATELLITE IMAGERY SHOWS A LONGWAVE TROUGH THAT EXTENDS FROM JAMES BAY BACK ACROSS THE CENTRAL PLAINS TO THE FOUR CORNERS. A LARGE NORTH-SOUTH RIDGE IS IN PLACE OFF THE WEST COAST WHILE A MORE PROGRESSIVE FLOW IS FOUND OVER CENTRAL CANADA WHERE ANOTHER TROUGH AXIS IS TRANSLATING SOUTHEASTWARD. AT THE SURFACE...A LOW IS MOVING NORTHEAST ACROSS FAR NORTHERN LAKE MICHIGAN WHICH WAS RESPONSIBLE FOR PUSHING A COLD FRONT ACROSS THE AREA LAST EVENING. A RIBBON OF HIGH PRESSURE STRETCHES FROM THE PACIFIC NORTHWEST TO THE CENTRAL HIGH PLAINS. TODAY...MANY CONCERNS THIS PERIOD RANGING FROM CLOUDS AND STRATUS TO DRIZZLE. THE UPPER TROUGH EXTENDING FROM JAMES BAY SOUTHWEST HAS A CLOSED CIRCULATION EMBEDDED WITHIN IT OVER CENTRAL WISCONSIN. THIS CLOSED CIRCULATION IS EXPECTED TO OPEN UP/WEAKEN WITH THE MAIN LONGWAVE TROUGH PIVOTING ACROSS THE AREA TODAY. IR SATELLITE SHOWS A VERY LARGE AREA OF STRATUS SPREADING EASTWARD ACROSS THE LOCAL AREA. WITH THE UPPER LOW WEAKENING AS IT ARRIVES...UPWARD MOTION WILL BE DIMINISHING THROUGH THE MORNING AND HAVE SEEN THIS ALREADY OCCURRING TO THE NORTH WHERE SHOWER COVERAGE/INTENSITY HAS BEEN WANING. WITH THE EXTENSIVE STRATUS IN PLACE SURFACE WARMING WILL BE LIMITED LEAVING LOW AND MID LEVEL LAPSE RATES MEAGER. WITH THIS IN MIND EXPECT THAT THE FOCUS FOR SHOWERS WILL REMAIN NORTH OF THE AREA LEADING TO LOWER/MINIMAL POPS ACROSS NORTHERN SECTIONS OF THE LOCAL AREA. WILL GO AHEAD AND ADD DRIZZLE ACROSS NORTHERN AREAS THROUGH THE MORNING HOWEVER WITH A DECENT DEPTH OF MOISTURE AND SOME WEAK ASCENT. UPSTREAM OBS OVER THE PAST SEVERAL HOURS HAVE ALSO SHOWN A FAIR AMOUNT OF DRIZZLE. AS ALLUDED TO...THE STRATUS WILL MAKE TEMPS A CHALLENGE. STRATUS DOES LOOK TO HOLD ON THROUGH THE AFTERNOON AND WILL COMBINE WITH LOW LEVEL COLD ADVECTION TO REALLY LIMIT WARMING. UNLESS SOME BREAKS CAN DEVELOP LATE IN THE DAY ALLOWING SOME MINIMAL SUNSHINE...DO NOT EXPECT MORE THAN ABOUT A 3-5 DEGREE DIURNAL INCREASE IN TEMPS FROM MORNING LOW...QUITE A BIT COOLER THAN MOST GUIDANCE. WILL THEREFORE KEEP HIGHS IN THE LOWER 50S IN NORTHERN AREAS TO THE MID EVEN UPPER 50S FAR SOUTH...WITH A BETTER CHANCE FOR SOME SUNSHINE OVER THE EXTREME SOUTHERN PORTIONS OF THE AREA. TONIGHT THROUGH THURSDAY...ATTENTION TURNS TO THE BASE OF THE LONGWAVE UPPER TROUGH OVER THE FOUR CORNERS WHERE ANOTHER CLOSED CIRCULATION IS TAKING SHAPE. THIS LOW WILL EJECT NORTHEASTWARD AND ACROSS THE AREA THURSDAY MORNING. THIS WILL BRING ANOTHER ROUND OF SHOWERS TO MUCH OF THE AREA...ESPECIALLY THE SOUTHEAST TWO-THIRDS... STARTING LATE TONIGHT AND CONTINUING THURSDAY MORNING. TEMPS TONIGHT WILL BE DEPENDENT ON CLOUD COVER. THE LOW CLOUDS LOOK TO HANG ON THROUGH THE EVENING IF NOT THROUGH THE NIGHT. MID CLOUDS WILL BE INCREASING AHEAD OF THE APPROACHING TROUGH OVERNIGHT. WITH SOME QUESTION ABOUT HOW LONG THE LOW CLOUDS WILL HANG ON AND IF THERE WILL BE A BREAK IN CLOUD COVER BEFORE THE HIGHER CLOUDS ARRIVE WILL ONLY RAISE OVERNIGHT LOWS A FEW DEGREES IN MOST AREAS FOR NOW...WITH POTENTIAL FOR ONLY A RELATIVELY SMALL FALL OVER DAYTIME HIGHS. THE PASSAGE OF THE UPPER LOW WILL ALLOW CLOUDS TO DECREASE THURSDAY AFTERNOON WHICH SHOULD ALLOW HIGHS TO WARM SEVERAL DEGREES OVER TODAY DESPITE SIMILAR MID LEVEL TEMPS. FRIDAY THROUGH TUESDAY...THE NEXT FEATURE OF INTEREST IS THE TROUGH MOVING SOUTHEAST ACROSS THE CANADIAN ROCKIES THIS MORNING. PART OF THIS WAVE LOOKS TO SPLIT OFF AND MOVE DUE SOUTH INTO THE CENTRAL ROCKIES WHILE THE REST TRACKS SOUTHEAST ACROSS THE NORTHERN PLAINS AND UPPER MISSISSIPPI RIVER VALLEY. ALL OF THIS ENERGY WILL RESULT IN A NEW LONGWAVE TROUGH RIGHT ACROSS THE MID SECTION OF THE COUNTRY. A WAVE WILL THEN ZIP NORTHEAST ACROSS THE AREA FRIDAY EVENING/NIGHT BRINGING A LOW CHANCE FOR POPS ACROSS THE AREA...ESPECIALLY SOUTHEAST. THE LONGWAVE WILL SHIFT EASTWARD SATURDAY INTO SUNDAY WHICH WILL ALLOW EVEN COLDER MID LEVEL AIR TO SPREAD INTO THE AREA...WITH H85 TEMPS FALLING BELOW 0C. PRECIP CHANCES LOOK LESS COHERENT BUT OVERALL MINIMAL SATURDAY AND SUNDAY...THOUGH LAKE EFFECT SHOWERS LOOK TO BE IN FULL SWING EAST OF LAKE MICHIGAN. HIGHS WILL BE IN THE 50S SATURDAY AND SUNDAY. ADDITIONAL ENERGY WILL TRACK SOUTHEAST ACROSS CENTRAL CANADA INTO THE UPPER MIDWEST AND WESTERN GREAT LAKES LATER SUNDAY THROUGH TUESDAY. THIS WILL LEAD TO ADDITIONAL PRECIP CHANCES AND CONTINUED COOL TEMPERATURES BUT THE DETAILS ARE UNCLEAR AT THIS RANGE. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * LOWER END MVFR STRATUS DECK. * POTENTIAL FOR PATCHY DRIZZLE THROUGH THIS AFTERNOON. KREIN //DISCUSSION...UPDATED 12Z... MAIN STORY TODAY WILL BE BROAD STRATUS DECK THAT IS EXPECTED TO IMPACT THE AREA WITH MVFR CIGS THROUGH THE REMAINDER OF THE AND POSSIBLY THROUGH THE OVERNIGHT HOURS. LOW PRESSURE IS LIFTING ACROSS EASTERN LAKE SUPERIOR INTO ONTARIO THIS MORNING WITH TROUGHING EXTENDING SOUTHWEST ACROSS WISCONSIN AND INTO EASTERN IOWA. STRATUS DECK EXTENDS ACROSS MUCH OF THE UPPER MIDWEST...AND IS EXPECTED TO VERY GRADUALLY SLIDE EAST THROUGH THE TAF PERIOD. WHILE THE SOUTHERN HALF OF THE CLOUD COVER IS MAINLY MVFR...IFR CIGS ARE WIDESPREAD ACROSS WISCONSIN AND NORTHEASTERN IOWA...PRIMARILY WITHIN THE TROUGH AXIS. IFR CIGS MAY REACH RFD THIS MORNING...HOWEVER BY THE TIME THE TROUGH MOVES INTO THE CHICAGO AREA...IT WILL WEAKEN WITH WEAK PRESSURE RISES AT THE SURFACE...MAKING IT LESS LIKELY FOR IFR INTO THE CHICAGO TERMINALS. MOST GUIDANCE ONCE AGAIN STRUGGLING BUT THE NAM SEEMS TO HAVE DECENT OF A HANDLE ON THE LOW LEVEL MOISTURE PROFILE...KEEPING MOISTURE IN PLACE THOUGH THE OVERNIGHT HOURS THEN DEPARTING EAST TOMORROW AFTERNOON. THERE IS ALSO A SLIGHT CONCERN FOR SOME PATCHY DRIZZLE DEVELOPING LATE THIS MORNING AS A SHEARED UPPER LEVEL DISTURBANCE MOVES ACROSS THE AREA. BEST TIME FRAME WOULD BE FROM 15Z TO 18Z...AND IT COULD REDUCE VISIBILITY TO 4-5SM...BUT TOO LOW CONFIDENCE RIGHT NOW TO INCLUDE IN THE TAF. BMD //ORD AND MDW CONFIDENCE...UPDATED 16Z... * MEDIUM TO HIGH CONFIDENCE IN MVFR CIGS THROUGH THE REST OF TODAY AND TONIGHT. LOW CONFIDENCE IN CHANCES FOR CIGS TO DROP TO IFR. * LOW CONFIDENCE IN SGFNT DRIZZLE IMPACTING TERMINALS. KREIN //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... THURSDAY NIGHT...VFR. FRIDAY...VFR. SATURDAY...SLT CHC SHRA. SUNDAY...VFR. MONDAY...CHC SHRA. TUESDAY...SLT CHC SHRA. BMD && .MARINE... 258 AM CDT LOW PRESSURE LIES OVER NORTHERN LAKE MICHIGAN THIS MORNING WITH A TRAILING COLD FRONT STRETCHING WEST ACROSS WISCONSIN INTO IOWA. WINDS ARE STRONGEST ACROSS THE SOUTHERN HALF OF THE LAKE WHERE 30 KTS ARE EXPECTED TO CONTINUE...THEN SHOULD BEGIN TO TAPER THIS AFTERNOON. A SMALL CRAFT ADVISORY WILL BE HOISTED FOR THE INDIANA NEARSHORE WATERS EAST OF BURNS HARBOR THROUGH LATE THIS EVENING. STRONGER WINDS ARE EXPECTED LATE THIS MORNING AND EARLY AFTERNOON ACROSS THE NORTHERN HALF OF THE LAKE AS THE COLD FRONT PUSHES ACROSS ALLOWING WINDS TO INCREASE WITH 30 KT GUSTS EXPECTED. WINDS WILL TAPER ACROSS THE ENTIRE LATE TONIGHT AS ANOTHER TROUGH DROPS INTO THE WESTERN LAKES REGION ALLOWING THE GRADIENT TO WEAKEN. WINDS BEGIN TO INCREASE AGAIN ON SATURDAY AS ANOTHER LOW DROPS SOUTHEAST ACROSS THE CANADIAN PRAIRIES THEN PIVOTS EAST ACROSS THE NORTHERN LAKES REGION. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE BURNS HARBOR TO MICHIGAN CITY IN UNTIL 10 PM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1044 AM CDT Wed Oct 16 2013 .DISCUSSION... ISSUED 1045 AM CDT Wed Oct 16 2013 Will be updating the forecast for cooler highs today (mid 50s IL river valley and lower 60s southeast IL) and increase cloud cover, similar to what we did yesterday. Otherwise rest of forecast looks on track today with breezy west winds of 10 to 20 mph and gusts of 20 to 25 mph. 1002 mb low pressure was over the eastern end of upper mi penisula with its cold front slicing through western Ohio and central KY and west TN while a secondary frontal trof was over central WI into southeast IA. Strong 550 dm 500 mb low was ne of Lake Superior with a large upper level trof extending sw into IA/NE and southern CO and northern NM where a short wave was. Low clouds over much of central and nw IL as far southeast as Mattoon and also mid level cloud deck southeast of I-70. Models show upper level trof pivoting se toward central IL and moving into the state on Thursday as short wave ejects from southern CO/northern NM toward the region. This should keep more clouds over central and nw parts of CWA while some sunshine over southeast IL allows for milder highs in the lower 60s. Temps currently in the lower 50s with Bloomington and Galesburg still at 49F. 07 && .AVIATION... ISSUED 700 AM CDT Wed Oct 16 2013 The surface low is progressing farther to the NE into the Great Lakes, while the cold front departs through Indiana. Wrap around moisture in Minnesota and Iowa has already reached PIA and SPI, and those MVFR clouds at 2-2.5K feet will reach all the way to DEC and CMI by 13z. A couple of hours of IFR clouds between 700-900 ft are being reported back across Iowa. Mixing and daytime heating should help to lift those ceilings above 1000 ft by the time that area reaches PIA around 16z. So no IFR conditions were included in the 12z TAF issuance. Ceilings may climb above 3k ft to VFR levels later this afternoon, but chances are that they will return to MVFR in the evening. We cant rule out some light drizzle or sprinkles today as a surface trough reaches IL later today. We will monitor those trends but keep a dry forecast for now. Winds will increase from the west this morning, with sustained speeds of 12-14kt and gusts to 22kt at times. Winds should diminish below 10kt by evening Shimon && .PREV DISCUSSION... ISSUED 243 AM CDT Wed Oct 16 2013 Latest surface map shows low pressure over the eastern part of the Michigan Upper Peninsula. The cold front extends southwest, and shows up as a narrow fine line through extreme southwest Indiana per radar imagery from the Evansville radar. Narrow clear slot just west of the Illinois River was about to be overtaken by a large stratocumulus deck from the northwest, and excessive mid and high clouds have been streaming northeast along the front across most of the forecast area. Main concern in the short term is with trying to time any cloud breakup today, followed by rain chances late tonight and early Thursday. Longer range issues focus on early weekend storm system and the cool weather trend which will last much of the forecast period. SHORT TERM...Today through Thursday... Latest RAP model guidance showing the mid/high clouds shifting south toward the Ohio Valley later today, as the stratocumulus pushes south of the I-72 corridor, although the NAM shows some decent break up by late morning. Given the expansive nature of the clouds, stretching all the way into northern Minnesota, will go with the more pessimistic route and keep skies mostly cloudy across the central and northern CWA today, with a bit of sunshine over the south. Went a couple degrees below the MOS guidance for highs, but this may need to be adjusted downward later if we are unable to get any breaks to develop. Shortwave currently near the 4 Corners region will zip eastward later today. 00Z model guidance closes this off as it reaches the Iowa/Illinois border toward sunrise Thursday, but ranges quite a bit in terms of any precipitation over our area. NAM is nearly dry with most of the precip near the remains of the earlier frontal boundary south of the Ohio River, while the GFS has a narrow rain axis just east of I-55. The ECMWF and Canadian models are much more bullish with widespread showers. Currently leaning toward more of the GFS solution but a bit more widespread with the showers Thursday morning, fairly similar in coverage to the earlier grids. However, am thinking that much of this will be out of the area by early afternoon, although some slight chance PoP`s will be in the afternoon forecast across the east. LONG TERM...Friday through Tuesday... A deepening upper trough over the central U.S. will be the main player this weekend, as a wedge of colder air drops southward from Canada. Some potential exists for light rain Friday night or early Saturday as the trough axis starts to shift eastward, but will maintain 20% PoP`s at this time. Some frost potential for Saturday night as winds lighten and temperatures fall into the upper 30s over the northern half of the CWA. Going into early next week, periodic lobes of energy will drop southward across the Midwest. The latest ECMWF remains quite chilly similar to the past couple runs, with 850 mb temperatures falling to around -5C by midweek, although the GFS is several degrees warmer. For now, have not strayed too far from the guidance, which keeps temperatures fairly similar throughout the period. Geelhart && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
911 AM CDT WED OCT 16 2013 .DISCUSSION... 306 AM CDT COOL AND PERIODICALLY DAMP WEATHER WILL DESCRIBE THE FORECAST PERIOD AS AN AMPLIFIED AND ACTIVE PATTERN SETS UP. WATER VAPOR SATELLITE IMAGERY SHOWS A LONGWAVE TROUGH THAT EXTENDS FROM JAMES BAY BACK ACROSS THE CENTRAL PLAINS TO THE FOUR CORNERS. A LARGE NORTH-SOUTH RIDGE IS IN PLACE OFF THE WEST COAST WHILE A MORE PROGRESSIVE FLOW IS FOUND OVER CENTRAL CANADA WHERE ANOTHER TROUGH AXIS IS TRANSLATING SOUTHEASTWARD. AT THE SURFACE...A LOW IS MOVING NORTHEAST ACROSS FAR NORTHERN LAKE MICHIGAN WHICH WAS RESPONSIBLE FOR PUSHING A COLD FRONT ACROSS THE AREA LAST EVENING. A RIBBON OF HIGH PRESSURE STRETCHES FROM THE PACIFIC NORTHWEST TO THE CENTRAL HIGH PLAINS. TODAY...MANY CONCERNS THIS PERIOD RANGING FROM CLOUDS AND STRATUS TO DRIZZLE. THE UPPER TROUGH EXTENDING FROM JAMES BAY SOUTHWEST HAS A CLOSED CIRCULATION EMBEDDED WITHIN IT OVER CENTRAL WISCONSIN. THIS CLOSED CIRCULATION IS EXPECTED TO OPEN UP/WEAKEN WITH THE MAIN LONGWAVE TROUGH PIVOTING ACROSS THE AREA TODAY. IR SATELLITE SHOWS A VERY LARGE AREA OF STRATUS SPREADING EASTWARD ACROSS THE LOCAL AREA. WITH THE UPPER LOW WEAKENING AS IT ARRIVES...UPWARD MOTION WILL BE DIMINISHING THROUGH THE MORNING AND HAVE SEEN THIS ALREADY OCCURRING TO THE NORTH WHERE SHOWER COVERAGE/INTENSITY HAS BEEN WANING. WITH THE EXTENSIVE STRATUS IN PLACE SURFACE WARMING WILL BE LIMITED LEAVING LOW AND MID LEVEL LAPSE RATES MEAGER. WITH THIS IN MIND EXPECT THAT THE FOCUS FOR SHOWERS WILL REMAIN NORTH OF THE AREA LEADING TO LOWER/MINIMAL POPS ACROSS NORTHERN SECTIONS OF THE LOCAL AREA. WILL GO AHEAD AND ADD DRIZZLE ACROSS NORTHERN AREAS THROUGH THE MORNING HOWEVER WITH A DECENT DEPTH OF MOISTURE AND SOME WEAK ASCENT. UPSTREAM OBS OVER THE PAST SEVERAL HOURS HAVE ALSO SHOWN A FAIR AMOUNT OF DRIZZLE. AS ALLUDED TO...THE STRATUS WILL MAKE TEMPS A CHALLENGE. STRATUS DOES LOOK TO HOLD ON THROUGH THE AFTERNOON AND WILL COMBINE WITH LOW LEVEL COLD ADVECTION TO REALLY LIMIT WARMING. UNLESS SOME BREAKS CAN DEVELOP LATE IN THE DAY ALLOWING SOME MINIMAL SUNSHINE...DO NOT EXPECT MORE THAN ABOUT A 3-5 DEGREE DIURNAL INCREASE IN TEMPS FROM MORNING LOW...QUITE A BIT COOLER THAN MOST GUIDANCE. WILL THEREFORE KEEP HIGHS IN THE LOWER 50S IN NORTHERN AREAS TO THE MID EVEN UPPER 50S FAR SOUTH...WITH A BETTER CHANCE FOR SOME SUNSHINE OVER THE EXTREME SOUTHERN PORTIONS OF THE AREA. TONIGHT THROUGH THURSDAY...ATTENTION TURNS TO THE BASE OF THE LONGWAVE UPPER TROUGH OVER THE FOUR CORNERS WHERE ANOTHER CLOSED CIRCULATION IS TAKING SHAPE. THIS LOW WILL EJECT NORTHEASTWARD AND ACROSS THE AREA THURSDAY MORNING. THIS WILL BRING ANOTHER ROUND OF SHOWERS TO MUCH OF THE AREA...ESPECIALLY THE SOUTHEAST TWO-THIRDS... STARTING LATE TONIGHT AND CONTINUING THURSDAY MORNING. TEMPS TONIGHT WILL BE DEPENDENT ON CLOUD COVER. THE LOW CLOUDS LOOK TO HANG ON THROUGH THE EVENING IF NOT THROUGH THE NIGHT. MID CLOUDS WILL BE INCREASING AHEAD OF THE APPROACHING TROUGH OVERNIGHT. WITH SOME QUESTION ABOUT HOW LONG THE LOW CLOUDS WILL HANG ON AND IF THERE WILL BE A BREAK IN CLOUD COVER BEFORE THE HIGHER CLOUDS ARRIVE WILL ONLY RAISE OVERNIGHT LOWS A FEW DEGREES IN MOST AREAS FOR NOW...WITH POTENTIAL FOR ONLY A RELATIVELY SMALL FALL OVER DAYTIME HIGHS. THE PASSAGE OF THE UPPER LOW WILL ALLOW CLOUDS TO DECREASE THURSDAY AFTERNOON WHICH SHOULD ALLOW HIGHS TO WARM SEVERAL DEGREES OVER TODAY DESPITE SIMILAR MID LEVEL TEMPS. FRIDAY THROUGH TUESDAY...THE NEXT FEATURE OF INTEREST IS THE TROUGH MOVING SOUTHEAST ACROSS THE CANADIAN ROCKIES THIS MORNING. PART OF THIS WAVE LOOKS TO SPLIT OFF AND MOVE DUE SOUTH INTO THE CENTRAL ROCKIES WHILE THE REST TRACKS SOUTHEAST ACROSS THE NORTHERN PLAINS AND UPPER MISSISSIPPI RIVER VALLEY. ALL OF THIS ENERGY WILL RESULT IN A NEW LONGWAVE TROUGH RIGHT ACROSS THE MID SECTION OF THE COUNTRY. A WAVE WILL THEN ZIP NORTHEAST ACROSS THE AREA FRIDAY EVENING/NIGHT BRINGING A LOW CHANCE FOR POPS ACROSS THE AREA...ESPECIALLY SOUTHEAST. THE LONGWAVE WILL SHIFT EASTWARD SATURDAY INTO SUNDAY WHICH WILL ALLOW EVEN COLDER MID LEVEL AIR TO SPREAD INTO THE AREA...WITH H85 TEMPS FALLING BELOW 0C. PRECIP CHANCES LOOK LESS COHERENT BUT OVERALL MINIMAL SATURDAY AND SUNDAY...THOUGH LAKE EFFECT SHOWERS LOOK TO BE IN FULL SWING EAST OF LAKE MICHIGAN. HIGHS WILL BE IN THE 50S SATURDAY AND SUNDAY. ADDITIONAL ENERGY WILL TRACK SOUTHEAST ACROSS CENTRAL CANADA INTO THE UPPER MIDWEST AND WESTERN GREAT LAKES LATER SUNDAY THROUGH TUESDAY. THIS WILL LEAD TO ADDITIONAL PRECIP CHANCES AND CONTINUED COOL TEMPERATURES BUT THE DETAILS ARE UNCLEAR AT THIS RANGE. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 14Z... * MVFR STRATUS DECK. * POTENTIAL FOR PATCHY DRIZZLE LATE THIS MORNING. KREIN //DISCUSSION...UPDATED 12Z... MAIN STORY TODAY WILL BE BROAD STRATUS DECK THAT IS EXPECTED TO IMPACT THE AREA WITH MVFR CIGS THROUGH THE REMAINDER OF THE AND POSSIBLY THROUGH THE OVERNIGHT HOURS. LOW PRESSURE IS LIFTING ACROSS EASTERN LAKE SUPERIOR INTO ONTARIO THIS MORNING WITH TROUGHING EXTENDING SOUTHWEST ACROSS WISCONSIN AND INTO EASTERN IOWA. STRATUS DECK EXTENDS ACROSS MUCH OF THE UPPER MIDWEST...AND IS EXPECTED TO VERY GRADUALLY SLIDE EAST THROUGH THE TAF PERIOD. WHILE THE SOUTHERN HALF OF THE CLOUD COVER IS MAINLY MVFR...IFR CIGS ARE WIDESPREAD ACROSS WISCONSIN AND NORTHEASTERN IOWA...PRIMARILY WITHIN THE TROUGH AXIS. IFR CIGS MAY REACH RFD THIS MORNING...HOWEVER BY THE TIME THE TROUGH MOVES INTO THE CHICAGO AREA...IT WILL WEAKEN WITH WEAK PRESSURE RISES AT THE SURFACE...MAKING IT LESS LIKELY FOR IFR INTO THE CHICAGO TERMINALS. MOST GUIDANCE ONCE AGAIN STRUGGLING BUT THE NAM SEEMS TO HAVE DECENT OF A HANDLE ON THE LOW LEVEL MOISTURE PROFILE...KEEPING MOISTURE IN PLACE THOUGH THE OVERNIGHT HOURS THEN DEPARTING EAST TOMORROW AFTERNOON. THERE IS ALSO A SLIGHT CONCERN FOR SOME PATCHY DRIZZLE DEVELOPING LATE THIS MORNING AS A SHEARED UPPER LEVEL DISTURBANCE MOVES ACROSS THE AREA. BEST TIME FRAME WOULD BE FROM 15Z TO 18Z...AND IT COULD REDUCE VISIBILITY TO 4-5SM...BUT TOO LOW CONFIDENCE RIGHT NOW TO INCLUDE IN THE TAF. BMD //ORD AND MDW CONFIDENCE...UPDATED 14Z... * MEDIUM CONFIDENCE IN MVFR CIGS THROUGH THE REST OF TODAY AND TONIGHT. LOW CONFIDENCE IN CHANCES FOR IFR. * LOW CONFIDENCE IN DRIZZLE IMPACTING TERMINALS. KREIN //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... THURSDAY NIGHT...VFR. FRIDAY...VFR. SATURDAY...SLT CHC SHRA. SUNDAY...VFR. MONDAY...CHC SHRA. TUESDAY...SLT CHC SHRA. BMD && .MARINE... 258 AM CDT LOW PRESSURE LIES OVER NORTHERN LAKE MICHIGAN THIS MORNING WITH A TRAILING COLD FRONT STRETCHING WEST ACROSS WISCONSIN INTO IOWA. WINDS ARE STRONGEST ACROSS THE SOUTHERN HALF OF THE LAKE WHERE 30 KTS ARE EXPECTED TO CONTINUE...THEN SHOULD BEGIN TO TAPER THIS AFTERNOON. A SMALL CRAFT ADVISORY WILL BE HOISTED FOR THE INDIANA NEARSHORE WATERS EAST OF BURNS HARBOR THROUGH LATE THIS EVENING. STRONGER WINDS ARE EXPECTED LATE THIS MORNING AND EARLY AFTERNOON ACROSS THE NORTHERN HALF OF THE LAKE AS THE COLD FRONT PUSHES ACROSS ALLOWING WINDS TO INCREASE WITH 30 KT GUSTS EXPECTED. WINDS WILL TAPER ACROSS THE ENTIRE LATE TONIGHT AS ANOTHER TROUGH DROPS INTO THE WESTERN LAKES REGION ALLOWING THE GRADIENT TO WEAKEN. WINDS BEGIN TO INCREASE AGAIN ON SATURDAY AS ANOTHER LOW DROPS SOUTHEAST ACROSS THE CANADIAN PRAIRIES THEN PIVOTS EAST ACROSS THE NORTHERN LAKES REGION. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE BURNS HARBOR TO MICHIGAN CITY IN UNTIL 10 PM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 701 AM CDT Wed Oct 16 2013 .DISCUSSION... ISSUED 243 AM CDT Wed Oct 16 2013 Latest surface map shows low pressure over the eastern part of the Michigan Upper Peninsula. The cold front extends southwest, and shows up as a narrow fine line through extreme southwest Indiana per radar imagery from the Evansville radar. Narrow clear slot just west of the Illinois River was about to be overtaken by a large stratocumulus deck from the northwest, and excessive mid and high clouds have been streaming northeast along the front across most of the forecast area. Main concern in the short term is with trying to time any cloud breakup today, followed by rain chances late tonight and early Thursday. Longer range issues focus on early weekend storm system and the cool weather trend which will last much of the forecast period. SHORT TERM...Today through Thursday... Latest RAP model guidance showing the mid/high clouds shifting south toward the Ohio Valley later today, as the stratocumulus pushes south of the I-72 corridor, although the NAM shows some decent break up by late morning. Given the expansive nature of the clouds, stretching all the way into northern Minnesota, will go with the more pessimistic route and keep skies mostly cloudy across the central and northern CWA today, with a bit of sunshine over the south. Went a couple degrees below the MOS guidance for highs, but this may need to be adjusted downward later if we are unable to get any breaks to develop. Shortwave currently near the 4 Corners region will zip eastward later today. 00Z model guidance closes this off as it reaches the Iowa/Illinois border toward sunrise Thursday, but ranges quite a bit in terms of any precipitation over our area. NAM is nearly dry with most of the precip near the remains of the earlier frontal boundary south of the Ohio River, while the GFS has a narrow rain axis just east of I-55. The ECMWF and Canadian models are much more bullish with widespread showers. Currently leaning toward more of the GFS solution but a bit more widespread with the showers Thursday morning, fairly similar in coverage to the earlier grids. However, am thinking that much of this will be out of the area by early afternoon, although some slight chance PoP`s will be in the afternoon forecast across the east. LONG TERM...Friday through Tuesday... A deepening upper trough over the central U.S. will be the main player this weekend, as a wedge of colder air drops southward from Canada. Some potential exists for light rain Friday night or early Saturday as the trough axis starts to shift eastward, but will maintain 20% PoP`s at this time. Some frost potential for Saturday night as winds lighten and temperatures fall into the upper 30s over the northern half of the CWA. Going into early next week, periodic lobes of energy will drop southward across the Midwest. The latest ECMWF remains quite chilly similar to the past couple runs, with 850 mb temperatures falling to around -5C by midweek, although the GFS is several degrees warmer. For now, have not strayed too far from the guidance, which keeps temperatures fairly similar throughout the period. Geelhart && .AVIATION... ISSUED 700 AM CDT Wed Oct 16 2013 The surface low is progressing farther to the NE into the Great Lakes, while the cold front departs through Indiana. Wrap around moisture in Minnesota and Iowa has already reached PIA and SPI, and those MVFR clouds at 2-2.5K feet will reach all the way to DEC and CMI by 13z. A couple of hours of IFR clouds between 700-900 ft are being reported back across Iowa. Mixing and daytime heating should help to lift those ceilings above 1000 ft by the time that area reaches PIA around 16z. So no IFR conditions were included in the 12z TAF issuance. Ceilings may climb above 3k ft to VFR levels later this afternoon, but chances are that they will return to MVFR in the evening. We cant rule out some light drizzle or sprinkles today as a surface trough reaches IL later today. We will monitor those trends but keep a dry forecast for now. Winds will increase from the west this morning, with sustained speeds of 12-14kt and gusts to 22kt at times. Winds should diminish below 10kt by evening Shimon && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
304 AM CDT WED OCT 16 2013 .DISCUSSION... 931 PM CDT ONLY REAL CHANGES TO THE GOING FORECAST WERE TO ADJUST HOURLY SKY TRENDS TO BETTER MATCH SATELLITE AND SHORT TERM GUIDANCE TRENDS IN SPREADING IN THE STRATUS DECK FROM THE NORTHWEST TONIGHT AND BEEFED UP SKY COVER A BIT INTO WEDNESDAY MORNING. COULD BE SOME DRIZZLE...ESPECIALLY NORTHWEST CWA LATE TONIGHT POTENTIALLY SPREADING EAST INTO NORTHEAST ILLINOIS WEDNESDAY MORNING WITHIN THE STRATUS DECK. THINKING THAT GOING POPS FOR TOMORROW LATE MORNING AND AFTERNOON ARE LIKELY TOO HIGH WITH EXTENSIVE CLOUD COVER LIKELY TO LIMIT HEATING/DESTABILIZATION WITH LOW INVERSION HEIGHTS MAKING SHOWERS LOOK FAIRLY UNLIKELY. IF ANYTHING WOULD APPEAR TO BE MORE OF A STRATUS/MORNING DRIZZLE TYPE SCENARIO WEDNESDAY MORNING WITH DRIZZLE TAPERING OFF IN THE AFTERNOON. GIVEN LOW CONFIDENCE HAVE OPTED TO LET GOING FORECAST POPS RIDE FOR WEDNESDAY AND WILL BRIEF ONCOMING NIGHT SHIFT AND ALLOW THEM TO GET A LOOK AT FULL SUITE OF 00Z DATA BEFORE MAKING ANY BIG ADJUSTMENTS. STRATUS DECK LIKELY TO RESULT IN VERY LITTLE HEATING WEDNESDAY AND GOING FORECAST HIGHS BELOW GUIDANCE LOOKS LIKE A GOOD TREND AND EVEN THOSE HIGHS COULD END UP A TAD WARM WHERE SUN DOESN`T BREAK OUT AT ALL. IZZI //PREV DISCUSSION... 307 PM CDT THE FORECAST CONCERNS ARE CENTERED ON TEMPERATURES FOR MUCH OF THE FORECAST...WITH CLOUD COVER BEING KEY. SMALL BUT FREQUENT CHANCES OF SHOWERS EXIST IN THE FORECAST...ESPECIALLY IN THE EXTENDED...AND ALSO WERE A FOCUS TODAY. SYNOPSIS...THE CLOSED UPPER LOW ACROSS THE UPPER MISSISSIPPI VALLEY IS BEGINNING TO GRADUALLY SHEAR AS IT MOVES NORTHEAST...WITH ANOTHER WELL-DEFINED CLOSED LOW ACROSS THE INTERMOUNTAIN WEST THAT WILL BRING A CHANCE FOR SHOWERS ON THU. AT THE SURFACE...1005MB LOW NEAR THE TWIN CITIES IS MOVING NORTHEAST WITH AN ASSOCIATED COLD FRONT...NOT FAR BEHIND THE LEADING EDGE OF THE SYSTEM DRY SLOT...PROGRESSING EASTWARD ACROSS NORTHWEST IL. THIS WILL LIKELY ALLOW MANY AREAS TO EXPERIENCE SUNSHINE FOR ONE TO TWO HOURS PRIOR TO SUNDOWN. THE MAIN AXIS OF SHOWERS THAT PASSED TODAY ASSOCIATED WITH THE MOISTURE TRANSPORT MAX ALONG THE WARM CONVEYOR BELT WILL CONTINUE TO SHIFT EAST...WITH A SMALL CHANCE FOR REDEVELOPING SHOWERS ALONG THE FRONT. THE VISIBLE SATELLITE HAS REVEALS A NARROW AXIS OF CONVERGENCE ALONG THE FRONT BUT THAT HAS SHOWN NO TREND FOR INCREASE...AND DIAGNOSTIC SOUNDINGS ADAPTED FOR SURFACE T/TDS INDICATE MAYBE 100-200 J/KG OF SBCAPE. CONTINUE SMALL POPS FOR THIS FEATURE UNTIL IT PASSES. TONIGHT AND WEDNESDAY...THE COLD FRONT WILL LEAD TO A QUICK DROP IN TEMPS AND EVEN A MORE RAPID FALL IN DEW POINTS. THE DRY SLOT AND ASSOCIATED SUPPRESSION...ALONG WITH STRONG SOUTHWEST WINDS IN THE CLOUD BEARING LAYER...SHOULD HELP TO SCOOT THE LOW CLOUDS EAST FOR MUCH OF THE EVE. WRAPAROUND CLOUDS ARE EXPECTED TO CREEP THEIR WAY IN FROM THE NORTHWEST ACROSS THE CWA OVERNIGHT AND EARLY WED MORNING. NAM AND NCEP WRF RH AND CONDENSATE FIELDS ARE IN STRONG AGREEMENT WITH THIS AND IT LINES UP WELL WITH CAA IN THE 850-925MB LAYER FOR STRATOCU. THE PATTERN IS FAVORABLE FOR THESE CLOUDS TO PREVAIL MUCH OF WED IF NOT A GOOD PART OF WED EVE...AND HAVE EXTENDED FURTHER IN FORECAST AND LONGER THAN WHAT GUIDANCE WOULD OUTRIGHT INDICATE. MID-LEVEL VORT AND COLD POCKET ALOFT WILL LIKELY BE ENOUGH TO GENERATE SCATTERED SHOWERS...ESPECIALLY IN WI...AND HAVE CONTINUED THE CHANCES ACROSS AREAS MAINLY NORTH OF I-80 ON WEDNESDAY. TEMPERATURES WILL BE STUNTED CONSIDERABLY BY THE CLOUDS AND EXPECT LITTLE RANGE BETWEEN MORNING STARTING VALUES AND DAYTIME MAXS. HAVE HIGHS MAINLY IN THE MID 50S BUT LOWER 50S CERTAINLY COULD MATERIALIZE. THURSDAY...UPPER LOW OVER THE INTERMOUNTAIN WEST BECOMES A PROGRESSIVE WAVE IN GUIDANCE SOLUTIONS INTO CENTRAL IL BY THU MORNING/EARLY AFTERNOON. HAVE LEANED TOWARD THE NAM AND EC WITH THIS WHICH ARE BOTH SLIGHTLY DEEPER AND FURTHER NORTH WITH ITS PATH...WHICH FAVOR SHOWER CHANCES OVER MORE OF THE CWA. HAVE INCREASED POPS WITH THIS VORT PASSAGE. TEMPS ON THU LOOK TO BE SLIGHTLY WARMER THAN WED...BUT CLOUDS AND POTENTIALLY SHOWERS WILL KEEP READINGS IN THE 50S. FRIDAY AND BEYOND...A LONG WAVE TROUGH PROGRESSIVELY ESTABLISHES ITSELF ACROSS CENTRAL NORTH AMERICA DURING THIS PERIOD WITH MULTIPLE SHORTWAVES WITHIN THE FLOW...WHICH LOOK TO OVERALL LOWER THE THICKNESSES AND TEMPERATURES ALOFT SLOWLY. THIS SHOULD REFLECT ITSELF IN SURFACE TEMPERATURES...ESPECIALLY HIGHS...BUT IT IS BECOMING MORE MUDDY. DURING SAT AND SUN CONFIDENCE IS ESPECIALLY LOW AS THE PAST TWO RUNS OF THE EC DO WANT TO SHOW A MORE ROBUST WARM SECTOR WITH A LOW IN THE NW FLOW...AND THAT INFRINGES INTO THE CWA ON SUN. THE 850MB TEMPS CLIMB TO 8C IN THE SOUTHERN CWA DURING THAT TIME...WHILE THE GEM AND GFS IN THAT PERIOD BASICALLY KEEP READINGS AT 0C OR BELOW. CERTAINLY LOOKS LIKE PERIODS OF CLOUDS FROM FRIDAY INTO EARLY NEXT WEEK THAT WILL BE A LARGER PLAYER IN TEMPS...ESPECIALLY MINS. SO OVERALL MANY PERIODS WITH CHANCE POPS...BUT THOSE WILL LIKELY BECOME BETTER DEFINED IN TIME. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * MVFR CIGS OVERSPREADING THE AREA OVERNIGHT...POTENTIALLY DROPPING NEAR OR TO IFR. BMD //DISCUSSION...UPDATED 06Z... LOW PRESSURE LIES OVER NORTHERN LAKE MICHIGAN TONIGHT WITH A SECONDARY FRONT TRAILING TO THE WSW ACROSS WISCONSIN INTO CENTRAL IOWA. A BROAD MVFR/IFR STRATUS DECK SPANS THE AREA OF LOW PRESSURE AND TRAILING FRONTAL TROUGH...AND IS GRADUALLY SPREADING EAST...REACHING THE ROCKFORD TERMINALS SHORTLY...AND THE CHICAGO TERMINALS LATE TONIGHT. LEADING EDGE OF THE STRATUS IS VFR BUT THEN DROPS TO MVFR SHORTLY THEREAFTER. CYCLONIC FLOW IS IN PLACE THROUGH THE DAY TOMORROW AND SHOULD RESULT IN LITTLE IF ANY IMPROVEMENT UNTIL AROUND 06Z THURSDAY WHEN FLOW BECOMES NEUTRAL...THAN ANTICYCLONIC. IN ADDITION TO THE LOW CIGS...AN UPPER LEVEL WAVE PASSING OVER THE AREA IN THE AFTERNOON MAY LEAD TO SOME PATCHY DRIZZLE. BMD //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH CONFIDENCE IN CIGS DROPPING TO MVFR...MEDIUM TO HIGH CONFIDENCE IN TIMING. LOW CONFIDENCE IN IFR AT THIS TIME. * MEDIUM CONFIDENCE IN WIND SPEED...MEDIUM TO HIGH CONFIDENCE IN DIRECTION. BMD //OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z... * THURSDAY...CHANCE OF SHRA. * FRIDAY...DRY/VFR. * SATURDAY...SLIGHT CHANCE OF SHRA. * SUNDAY...DRY/VFR. * MONDAY...CHANCE OF SHRA. && .MARINE... 258 AM CDT LOW PRESSURE LIES OVER NORTHERN LAKE MICHIGAN THIS MORNING WITH A TRAILING COLD FRONT STRETCHING WEST ACROSS WISCONSIN INTO IOWA. WINDS ARE STRONGEST ACROSS THE SOUTHERN HALF OF THE LAKE WHERE 30 KTS ARE EXPECTED TO CONTINUE...THEN SHOULD BEGIN TO TAPER THIS AFTERNOON. A SMALL CRAFT ADVISORY WILL BE HOISTED FOR THE INDIANA NEARSHORE WATERS EAST OF BURNS HARBOR THROUGH LATE THIS EVENING. STRONGER WINDS ARE EXPECTED LATE THIS MORNING AND EARLY AFTERNOON ACROSS THE NORTHERN HALF OF THE LAKE AS THE COLD FRONT PUSHES ACROSS ALLOWING WINDS TO INCREASE WITH 30 KT GUSTS EXPECTED. WINDS WILL TAPER ACROSS THE ENTIRE LATE TONIGHT AS ANOTHER TROUGH DROPS INTO THE WESTERN LAKES REGION ALLOWING THE GRADIENT TO WEAKEN. WINDS BEGIN TO INCREASE AGAIN ON SATURDAY AS ANOTHER LOW DROPS SOUTHEAST ACROSS THE CANADIAN PRAIRIES THEN PIVOTS EAST ACROSS THE NORTHERN LAKES REGION. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE BURNS HARBOR TO MICHIGAN CITY IN UNTIL 10 PM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 244 AM CDT Wed Oct 16 2013 .DISCUSSION... ISSUED 243 AM CDT Wed Oct 16 2013 Latest surface map shows low pressure over the eastern part of the Michigan Upper Peninsula. The cold front extends southwest, and shows up as a narrow fine line through extreme southwest Indiana per radar imagery from the Evansville radar. Narrow clear slot just west of the Illinois River was about to be overtaken by a large stratocumulus deck from the northwest, and excessive mid and high clouds have been streaming northeast along the front across most of the forecast area. Main concern in the short term is with trying to time any cloud breakup today, followed by rain chances late tonight and early Thursday. Longer range issues focus on early weekend storm system and the cool weather trend which will last much of the forecast period. SHORT TERM...Today through Thursday... Latest RAP model guidance showing the mid/high clouds shifting south toward the Ohio Valley later today, as the stratocumulus pushes south of the I-72 corridor, although the NAM shows some decent break up by late morning. Given the expansive nature of the clouds, stretching all the way into northern Minnesota, will go with the more pessimistic route and keep skies mostly cloudy across the central and northern CWA today, with a bit of sunshine over the south. Went a couple degrees below the MOS guidance for highs, but this may need to be adjusted downward later if we are unable to get any breaks to develop. Shortwave currently near the 4 Corners region will zip eastward later today. 00Z model guidance closes this off as it reaches the Iowa/Illinois border toward sunrise Thursday, but ranges quite a bit in terms of any precipitation over our area. NAM is nearly dry with most of the precip near the remains of the earlier frontal boundary south of the Ohio River, while the GFS has a narrow rain axis just east of I-55. The ECMWF and Canadian models are much more bullish with widespread showers. Currently leaning toward more of the GFS solution but a bit more widespread with the showers Thursday morning, fairly similar in coverage to the earlier grids. However, am thinking that much of this will be out of the area by early afternoon, although some slight chance PoP`s will be in the afternoon forecast across the east. LONG TERM...Friday through Tuesday... A deepening upper trough over the central U.S. will be the main player this weekend, as a wedge of colder air drops southward from Canada. Some potential exists for light rain Friday night or early Saturday as the trough axis starts to shift eastward, but will maintain 20% PoP`s at this time. Some frost potential for Saturday night as winds lighten and temperatures fall into the upper 30s over the northern half of the CWA. Going into early next week, periodic lobes of energy will drop southward across the Midwest. The latest ECMWF remains quite chilly similar to the past couple runs, with 850 mb temperatures falling to around -5C by midweek, although the GFS is several degrees warmer. For now, have not strayed too far from the guidance, which keeps temperatures fairly similar throughout the period. Geelhart && .AVIATION... ISSUED 1159 PM CDT Tue Oct 15 2013 VFR conditions prevail across the central Illinois terminals at the moment, with westerly winds in the wake of the today`s cold front. Wrap around cloud cover, with cigs ranging in height from VFR to IFR, is spreading toward the area. The models are having trouble with how quickly these clouds should arrive, and satellite extrapolation is likely to be the best estimation at this point. For now, have kept MVFR cigs restricted to KPIA and KBMI, with VFR cigs elsewhere. Cigs should rise to VFR area-wide by the end of the 06Z TAF valid time. Bak && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1217 PM CDT WED OCT 16 2013 .UPDATE... ISSUED AT 1210 PM CDT WED OCT 16 2013 THE EARLIER CONCERN IS BEING REALIZED...TEMPERATURES ARE BARELY MOVING IF AT ALL. THUS MAX TEMPERATURES ARE BEING LOWERED AGAIN. SATELLITE TRENDS SHOW DIURNAL COLD WX CLOUDS DEVELOPING ON THE BACK SIDE OF THE LOW CLOUDS. THESE CLOUDS WILL PERSIST THROUGH SUNSET AND THEN DISSIPATE. HOWEVER...THE EFFECT WILL BE TO DELAY ANY CLEARING FURTHER. TRENDS FROM THE RAP ARE NOW POINTING TO KEEPING CLOUDS ACROSS MOST OF THE AREA THROUGH SUNRISE WITH CLEARING ON THURSDAY AS THE UPPER LEVEL DISTURBANCE MOVES NORTHEAST. THUS MIN TEMPERATURES FOR TONIGHT HAVE BEEN RAISED IN ANTICIPATION OF CLOUDS REMAINING ACROSS THE AREA. ..08.. UPDATE ISSUED AT 1028 AM CDT WED OCT 16 2013 SPOTTY DRIZZLE APPEARS TO BE ASSOCIATED WITH LIFT FROM THE 700 AND 500MB TROFS AND LOW CONDENSATION PRESSURE DEFICITS AT 700MB. RAP TRENDS HAVE THE OVERALL LIFT DISSIPATING DURING THE AFTERNOON SUGGESTING THE POTENTIAL FOR DRIZZLE INTO THE EARLY AFTERNOON. IF THE TRENDS WITH THE RAP ARE CORRECT...AREAS GENERALLY ALONG/NORTH OF HWY 30 WOULD BE FAVORED FOR DRIZZLE. TEMPERATURES SO FAR HAVE RESPONDED A FEW DEGREES SINCE THE OVERNIGHT MINS. TRENDS WILL BE MONITORED BUT THE POTENTIAL EXISTS FOR ANOTHER LOWERING OF MAX TEMPERATURES BY A FEW MORE DEGREES. UPDATE ISSUED AT 842 AM CDT WED OCT 16 2013 BASED ON CURRENT SATELLITE TRENDS...CLEARING LOOKS DOUBTFUL PRIOR TO SUNSET. RECENT RAP TRENDS ALSO SUGGEST CLOUDS REMAINING ACROSS THE AREA AS WELL DURING THE DAYLIGHT HOURS. CLOUD COVER COMBINED WITH THE WEAKENING OCTOBER SUN INDICATE A VERY SMALL DIURNAL RISE IN TEMPERATURES DURING THE DAY. ..08.. && .SYNOPSIS... ISSUED AT 300 AM CDT WED OCT 16 2013 A POSITIVELY TILTED UPPER TROF EXTENDED FROM THE WESTERN GREAT LAKES INTO SOUTHERN CA AND AZ TUESDAY EVENING. A SURFACE LOW WAS LOCATED OVER LAKE SUPERIOR WITH CYCLONIC FLOW AROUND THE LOW EXTENDING WEST INTO SOUTHWESTERN MN AND WESTERN IA. WIDESPREAD LOW CLOUDS WERE ASSOCIATED WITH THE CYCLONIC FLOW. SOME PATCHY DRIZZLE OR LIGHT RAIN WAS OCCURRING FROM CENTRAL MN INTO NORTHERN IA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 300 AM CDT WED OCT 16 2013 CLOUDS TRENDS WILL BE THE MAIN CONCERN TODAY AND TONIGHT AS THE GREAT LAKES SURFACE LOW MOVES OFF TO THE NORTHEAST AND THE TRAILING CYCLONIC FLOW WEAKENS. THE LOW CLOUDS HAVE OVERSPREAD THE ENTIRE AREA EARLY THIS MORNING AND EXTEND INTO EASTERN NE AND SOUTH DAKOTA SO IT/S DOUBTFUL THAT ANY CLEARING WILL OCCUR TODAY WITH THE CYCLONIC FLOW REMAINING OVER THE AREA. PATCHY DRIZZLE OR LIGHT RAIN SHOULD BE CONFINED TO THE NORTHERN HALF OF THE FORECAST AREA TODAY. THERE IS SOME DISAGREEMENT BETWEEN THE MODELS ON CLEARING TONIGHT. THE GFS SUGGESTS THE WEST WILL SEE SOME CLEARING LATE WHILE THE NAM HOLDS HIGH H8 RH OVER THE ENTIRE AREA THROUGH 12Z THURSDAY ALONG WITH SOME WEAK LOW LEVEL CONVERGENCE...SUPPORTING LITTLE IF ANY CLEARING. IF THE LOW CLOUDS WOULD CLEAR OVER PARTS OF THE AREA TONIGHT...ANY CLEARING SHOULD BE BRIEF WITH MID/HIGH CLOUDS SPREADING OVER THE AREA AHEAD OF A S/W LIFTING OUT OF THE SOUTHWESTERN U.S. THE S/W WILL ALSO BRING A LOW CHANCE OF SOME LIGHT RAIN TO THE SOUTHEASTERN THIRD AFTER MIDNIGHT. THE EXTENSIVE CLOUD COVER WILL KEEP TEMPERATURES FROM CHANGING MUCH TODAY AND TONIGHT. 50S ARE EXPECTED TODAY WITH OVERNIGHT LOWS IN THE UPPER 30S AND LOWER 40S. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 300 AM CDT WED OCT 16 2013 PATTERN CHANGE TO A PREVAILING NW FLOW TO BRING ABOUT A CHANGE TO BELOW TEMPERATURES BY THE WEEKEND...WHICH WILL REMAIN PLACE THROUGH MUCH OF NEXT WEEK. IN THE TRANSITION...WEAK SYSTEMS WILL BRING PERIODIC CHANCES FOR LIGHT PRECIPITATION LATE THIS WEEK INTO THE WEEKEND. THURSDAY THROUGH FRIDAY NIGHT...VERY LIGHT RAIN OR DRIZZLE ASSOCIATED WITH ISENTROPIC LIFT UNDER THE SHORTWAVE EXITING TO THE EAST WILL BE HANDLED WITH VERY LOW POPS THU MORNING. BY AFTERNOON...A TRANSITORY MID LEVEL SHORTWAVE RIDGE THAT FOLLOWS SHOULD BRING CLEARING SKIES ALLOWING TEMPERATURES TO RECOVER INTO THE LOWER TO MID 60S. ANOTHER SHORTWAVE AND THE BROAD CYCLONIC FLOW ALOFT SHOULD BRING INCREASING CLOUDS OVERNIGHT...BUT WITH THE BEST FORCING WELL TO THE NORTH...WILL NOT ANTICIPATE ANY PRECIPITATION. CLOUD COVER SHOULD CONFINE MINS TO THE UPPER 30S TO LOWER 40S. THE NEXT SYSTEM BRUSHES PAST TO THE SOUTH LATE FRIDAY AND WILL HAVE SLIGHT CHANCE POPS FOR LIGHT RAIN ACROSS THE SOUTH FOR FRIDAY NIGHT. COLD ADVECTION GRADUALLY INCREASES THROUGH THIS PERIOD...AND BY FRIDAY NIGHT...850 MB TEMPERATURES NEAR TO BELOW ZERO CELSIUS ARE PROGGED OVER THE AREA. WILL THUS NEED DEEP MIXING TO REACH HIGHS IN THE 50S FRIDAY...THEN CLOUD COVER TO MAINTAIN LOWS IN THE MID TO UPPER 30S FRIDAY NIGHT. OVER THE WEEKEND...THE NEXT SHORTWAVE IS GENERALLY DEPICTED PASSING TO THE NORTH AROUND SATURDAY NIGHT...AND WILL MAINTAIN ONLY SLIGHT CHANCES FOR RAIN IN THE FAR NORTH. OTHERWISE...IMPROVING MODEL CONSISTENCY...BOTH FROM RUN TO RUN AND BETWEEN MODELS...SHOW 850 MB TEMPERATURES COOLING TO ZERO TO 4 BELOW BY SUNDAY SUPPORT WELL BELOW NORMAL SURFACE TEMPERATURES. ADVERTISED HIGHS IN THE 50S MAY BE TOO OPTIMISTIC...ESPECIALLY SUNDAY DEPENDING ON CLOUD TRENDS. LIKEWISE...CURRENT OVERNIGHT LOWS COULD POTENTIALLY BE COLD ENOUGH FOR A WIDESPREAD KILLING FREEZE...ESPECIALLY SUNDAY MORNING. HOWEVER...FOR NOW...WITH UNCERTAINTIES IN CLOUD COVER AND THE TIMING OF PASSING SURFACE RIDGE AXIS...LOWS WILL BE MAINTAINED IN THE 30S. NEXT WEEK...A CYCLONIC NW FLOW WITH PERIODIC SHORTWAVES AND REINFORCING SURFACE COLD FRONTS SETS UP OVER THE AREA THROUGH MOST OF THE WEEK. THERE IS HIGH CONFIDENCE THAT MUCH OF THE WEEK WILL FEATURE BELOW TO WELL BELOW NORMAL TEMPERATURES. HOWEVER... CHALLENGES WITH THE CRITICAL TIMING AND STRENGTH OF PASSING SHORTWAVES MAKES THIS A LOW PREDICTABILITY PATTERN THIS FAR OUT. FOR NOW...THERE IS ENOUGH CONSENSUS IN THE MODEL BLENDS TO PLACE LOW CHANCE POPS OVER MAINLY THE NORTH FOR SUNDAY NIGHT INTO MONDAY...AND THEN MORE WIDESPREAD HIGHER CHANCES FOR TUE INTO TUE NIGHT. THE LATEST GFS AND ECMWF INDICATE A STRONG SURGE OF COLD AIR BEHIND TUESDAY NIGHT/S COLD FRONT...THAT COULD LIMIT MIDWEEK HIGHS TO THE UPPER 30S OVER AT LEAST THE NORTH AND RESULT IN WIDESPREAD 20S FOR LOWS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1210 PM CDT WED OCT 16 2013 MVFR CONDITIONS WITH A FEW POCKETS OF IFR CIGS WILL PERSIST THROUGH 00Z/17 AS MOISTURE REMAINS TRAPPED BELOW THE INVERSION. AFT 00Z/17 MVFR CONDITIONS WILL CONTINUE WITH A SLOW IMPROVEMENT TO VFR CIGS. AFT 12Z/17 CLEARING WILL COMMENCE FROM SOUTHWEST TO NORTHEAST. ..08.. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...08 SYNOPSIS...DLF SHORT TERM...DLF LONG TERM...SHEETS AVIATION...08
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1033 AM CDT WED OCT 16 2013 .UPDATE... ISSUED AT 1028 AM CDT WED OCT 16 2013 SPOTTY DRIZZLE APPEARS TO BE ASSOCIATED WITH LIFT FROM THE 700 AND 500MB TROFS AND LOW CONDENSATION PRESSURE DEFICITS AT 700MB. RAP TRENDS HAVE THE OVERALL LIFT DISSIPATING DURING THE AFTERNOON SUGGESTING THE POTENTIAL FOR DRIZZLE INTO THE EARLY AFTERNOON. IF THE TRENDS WITH THE RAP ARE CORRECT...AREAS GENERALLY ALONG/NORTH OF HWY 30 WOULD BE FAVORED FOR DRIZZLE. TEMPERATURES SO FAR HAVE RESPONDED A FEW DEGREES SINCE THE OVERNIGHT MINS. TRENDS WILL BE MONITORED BUT THE POTENTIAL EXISTS FOR ANOTHER LOWERING OF MAX TEMPERATURES BY A FEW MORE DEGREES. UPDATE ISSUED AT 842 AM CDT WED OCT 16 2013 BASED ON CURRENT SATELLITE TRENDS...CLEARING LOOKS DOUBTFUL PRIOR TO SUNSET. RECENT RAP TRENDS ALSO SUGGEST CLOUDS REMAINING ACROSS THE AREA AS WELL DURING THE DAYLIGHT HOURS. CLOUD COVER COMBINED WITH THE WEAKENING OCTOBER SUN INDICATE A VERY SMALL DIURNAL RISE IN TEMPERATURES DURING THE DAY. ..08.. && .SYNOPSIS... ISSUED AT 300 AM CDT WED OCT 16 2013 A POSITIVELY TILTED UPPER TROF EXTENDED FROM THE WESTERN GREAT LAKES INTO SOUTHERN CA AND AZ TUESDAY EVENING. A SURFACE LOW WAS LOCATED OVER LAKE SUPERIOR WITH CYCLONIC FLOW AROUND THE LOW EXTENDING WEST INTO SOUTHWESTERN MN AND WESTERN IA. WIDESPREAD LOW CLOUDS WERE ASSOCIATED WITH THE CYCLONIC FLOW. SOME PATCHY DRIZZLE OR LIGHT RAIN WAS OCCURRING FROM CENTRAL MN INTO NORTHERN IA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 300 AM CDT WED OCT 16 2013 CLOUDS TRENDS WILL BE THE MAIN CONCERN TODAY AND TONIGHT AS THE GREAT LAKES SURFACE LOW MOVES OFF TO THE NORTHEAST AND THE TRAILING CYCLONIC FLOW WEAKENS. THE LOW CLOUDS HAVE OVERSPREAD THE ENTIRE AREA EARLY THIS MORNING AND EXTEND INTO EASTERN NE AND SOUTH DAKOTA SO IT/S DOUBTFUL THAT ANY CLEARING WILL OCCUR TODAY WITH THE CYCLONIC FLOW REMAINING OVER THE AREA. PATCHY DRIZZLE OR LIGHT RAIN SHOULD BE CONFINED TO THE NORTHERN HALF OF THE FORECAST AREA TODAY. THERE IS SOME DISAGREEMENT BETWEEN THE MODELS ON CLEARING TONIGHT. THE GFS SUGGESTS THE WEST WILL SEE SOME CLEARING LATE WHILE THE NAM HOLDS HIGH H8 RH OVER THE ENTIRE AREA THROUGH 12Z THURSDAY ALONG WITH SOME WEAK LOW LEVEL CONVERGENCE...SUPPORTING LITTLE IF ANY CLEARING. IF THE LOW CLOUDS WOULD CLEAR OVER PARTS OF THE AREA TONIGHT...ANY CLEARING SHOULD BE BRIEF WITH MID/HIGH CLOUDS SPREADING OVER THE AREA AHEAD OF A S/W LIFTING OUT OF THE SOUTHWESTERN U.S. THE S/W WILL ALSO BRING A LOW CHANCE OF SOME LIGHT RAIN TO THE SOUTHEASTERN THIRD AFTER MIDNIGHT. THE EXTENSIVE CLOUD COVER WILL KEEP TEMPERATURES FROM CHANGING MUCH TODAY AND TONIGHT. 50S ARE EXPECTED TODAY WITH OVERNIGHT LOWS IN THE UPPER 30S AND LOWER 40S. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 300 AM CDT WED OCT 16 2013 PATTERN CHANGE TO A PREVAILING NW FLOW TO BRING ABOUT A CHANGE TO BELOW TEMPERATURES BY THE WEEKEND...WHICH WILL REMAIN PLACE THROUGH MUCH OF NEXT WEEK. IN THE TRANSITION...WEAK SYSTEMS WILL BRING PERIODIC CHANCES FOR LIGHT PRECIPITATION LATE THIS WEEK INTO THE WEEKEND. THURSDAY THROUGH FRIDAY NIGHT...VERY LIGHT RAIN OR DRIZZLE ASSOCIATED WITH ISENTROPIC LIFT UNDER THE SHORTWAVE EXITING TO THE EAST WILL BE HANDLED WITH VERY LOW POPS THU MORNING. BY AFTERNOON...A TRANSITORY MID LEVEL SHORTWAVE RIDGE THAT FOLLOWS SHOULD BRING CLEARING SKIES ALLOWING TEMPERATURES TO RECOVER INTO THE LOWER TO MID 60S. ANOTHER SHORTWAVE AND THE BROAD CYCLONIC FLOW ALOFT SHOULD BRING INCREASING CLOUDS OVERNIGHT...BUT WITH THE BEST FORCING WELL TO THE NORTH...WILL NOT ANTICIPATE ANY PRECIPITATION. CLOUD COVER SHOULD CONFINE MINS TO THE UPPER 30S TO LOWER 40S. THE NEXT SYSTEM BRUSHES PAST TO THE SOUTH LATE FRIDAY AND WILL HAVE SLIGHT CHANCE POPS FOR LIGHT RAIN ACROSS THE SOUTH FOR FRIDAY NIGHT. COLD ADVECTION GRADUALLY INCREASES THROUGH THIS PERIOD...AND BY FRIDAY NIGHT...850 MB TEMPERATURES NEAR TO BELOW ZERO CELSIUS ARE PROGGED OVER THE AREA. WILL THUS NEED DEEP MIXING TO REACH HIGHS IN THE 50S FRIDAY...THEN CLOUD COVER TO MAINTAIN LOWS IN THE MID TO UPPER 30S FRIDAY NIGHT. OVER THE WEEKEND...THE NEXT SHORTWAVE IS GENERALLY DEPICTED PASSING TO THE NORTH AROUND SATURDAY NIGHT...AND WILL MAINTAIN ONLY SLIGHT CHANCES FOR RAIN IN THE FAR NORTH. OTHERWISE...IMPROVING MODEL CONSISTENCY...BOTH FROM RUN TO RUN AND BETWEEN MODELS...SHOW 850 MB TEMPERATURES COOLING TO ZERO TO 4 BELOW BY SUNDAY SUPPORT WELL BELOW NORMAL SURFACE TEMPERATURES. ADVERTISED HIGHS IN THE 50S MAY BE TOO OPTIMISTIC...ESPECIALLY SUNDAY DEPENDING ON CLOUD TRENDS. LIKEWISE...CURRENT OVERNIGHT LOWS COULD POTENTIALLY BE COLD ENOUGH FOR A WIDESPREAD KILLING FREEZE...ESPECIALLY SUNDAY MORNING. HOWEVER...FOR NOW...WITH UNCERTAINTIES IN CLOUD COVER AND THE TIMING OF PASSING SURFACE RIDGE AXIS...LOWS WILL BE MAINTAINED IN THE 30S. NEXT WEEK...A CYCLONIC NW FLOW WITH PERIODIC SHORTWAVES AND REINFORCING SURFACE COLD FRONTS SETS UP OVER THE AREA THROUGH MOST OF THE WEEK. THERE IS HIGH CONFIDENCE THAT MUCH OF THE WEEK WILL FEATURE BELOW TO WELL BELOW NORMAL TEMPERATURES. HOWEVER... CHALLENGES WITH THE CRITICAL TIMING AND STRENGTH OF PASSING SHORTWAVES MAKES THIS A LOW PREDICTABILITY PATTERN THIS FAR OUT. FOR NOW...THERE IS ENOUGH CONSENSUS IN THE MODEL BLENDS TO PLACE LOW CHANCE POPS OVER MAINLY THE NORTH FOR SUNDAY NIGHT INTO MONDAY...AND THEN MORE WIDESPREAD HIGHER CHANCES FOR TUE INTO TUE NIGHT. THE LATEST GFS AND ECMWF INDICATE A STRONG SURGE OF COLD AIR BEHIND TUESDAY NIGHT/S COLD FRONT...THAT COULD LIMIT MIDWEEK HIGHS TO THE UPPER 30S OVER AT LEAST THE NORTH AND RESULT IN WIDESPREAD 20S FOR LOWS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 639 AM CDT WED OCT 16 2013 CYCLONIC FLOW AROUND LOW PRESSURE OVER LAKE HURON WILL KEEP MVFR CIGS OVER THE AREA FOR THE REST OF THE TODAY. THERE IS A NARROW BAND OF IFR CIGS OVER NORTHERN IOWA WITH THE SOUTHERN EDGE WAS AS FAR SOUTH AS HIGHWAY 20. THESE LOW CIGS COULD SAG SOUTH INTO THE HWY 30 CORRIDOR YET THIS MORNING. THE IFR CIGS WILL BE ACCOMPANIED BY SOME PATCHY DRIZZLE WITH VSBYS IN THE 3 TO 5SM RANGE. THE LOWER CIGS SHOULD LIFT ABOVE 1000 FT BY LATE MORNING OR EARLY AFTERNOON. THERE IS UNCERTAINTY ABOUT CEILING TRENDS LATE TONIGHT WITH THE 06Z MODELS RUNS SUGGESTING SOME CLEARING WILL TAKE PLACE AFTER MIDNIGHT. FOR NOW MAINTAINED CIGS AROUND 3000 FT AT ALL TAF SITES THROUGH 12Z AND WAIT TO SEE IF LATER RUNS CONTINUE THE TREND OF FASTER CLEARING. IF THERE IS SOME CLEARING OVERNIGHT THEN THERE IS POTENTIAL FOR FOG DEVELOPMENT. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...08 SYNOPSIS...DLF SHORT TERM...DLF LONG TERM...SHEETS AVIATION...DLF
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
845 AM CDT WED OCT 16 2013 .UPDATE... ISSUED AT 842 AM CDT WED OCT 16 2013 BASED ON CURRENT SATELLITE TRENDS...CLEARING LOOKS DOUBTFUL PRIOR TO SUNSET. RECENT RAP TRENDS ALSO SUGGEST CLOUDS REMAINING ACROSS THE AREA AS WELL DURING THE DAYLIGHT HOURS. CLOUD COVER COMBINED WITH THE WEAKENING OCTOBER SUN INDICATE A VERY SMALL DIURNAL RISE IN TEMPERATURES DURING THE DAY. ..08.. && .SYNOPSIS... ISSUED AT 300 AM CDT WED OCT 16 2013 A POSITIVELY TILTED UPPER TROF EXTENDED FROM THE WESTERN GREAT LAKES INTO SOUTHERN CA AND AZ TUESDAY EVENING. A SURFACE LOW WAS LOCATED OVER LAKE SUPERIOR WITH CYCLONIC FLOW AROUND THE LOW EXTENDING WEST INTO SOUTHWESTERN MN AND WESTERN IA. WIDESPREAD LOW CLOUDS WERE ASSOCIATED WITH THE CYCLONIC FLOW. SOME PATCHY DRIZZLE OR LIGHT RAIN WAS OCCURRING FROM CENTRAL MN INTO NORTHERN IA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 300 AM CDT WED OCT 16 2013 CLOUDS TRENDS WILL BE THE MAIN CONCERN TODAY AND TONIGHT AS THE GREAT LAKES SURFACE LOW MOVES OFF TO THE NORTHEAST AND THE TRAILING CYCLONIC FLOW WEAKENS. THE LOW CLOUDS HAVE OVERSPREAD THE ENTIRE AREA EARLY THIS MORNING AND EXTEND INTO EASTERN NE AND SOUTH DAKOTA SO IT/S DOUBTFUL THAT ANY CLEARING WILL OCCUR TODAY WITH THE CYCLONIC FLOW REMAINING OVER THE AREA. PATCHY DRIZZLE OR LIGHT RAIN SHOULD BE CONFINED TO THE NORTHERN HALF OF THE FORECAST AREA TODAY. THERE IS SOME DISAGREEMENT BETWEEN THE MODELS ON CLEARING TONIGHT. THE GFS SUGGESTS THE WEST WILL SEE SOME CLEARING LATE WHILE THE NAM HOLDS HIGH H8 RH OVER THE ENTIRE AREA THROUGH 12Z THURSDAY ALONG WITH SOME WEAK LOW LEVEL CONVERGENCE...SUPPORTING LITTLE IF ANY CLEARING. IF THE LOW CLOUDS WOULD CLEAR OVER PARTS OF THE AREA TONIGHT...ANY CLEARING SHOULD BE BRIEF WITH MID/HIGH CLOUDS SPREADING OVER THE AREA AHEAD OF A S/W LIFTING OUT OF THE SOUTHWESTERN U.S. THE S/W WILL ALSO BRING A LOW CHANCE OF SOME LIGHT RAIN TO THE SOUTHEASTERN THIRD AFTER MIDNIGHT. THE EXTENSIVE CLOUD COVER WILL KEEP TEMPERATURES FROM CHANGING MUCH TODAY AND TONIGHT. 50S ARE EXPECTED TODAY WITH OVERNIGHT LOWS IN THE UPPER 30S AND LOWER 40S. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 300 AM CDT WED OCT 16 2013 PATTERN CHANGE TO A PREVAILING NW FLOW TO BRING ABOUT A CHANGE TO BELOW TEMPERATURES BY THE WEEKEND...WHICH WILL REMAIN PLACE THROUGH MUCH OF NEXT WEEK. IN THE TRANSITION...WEAK SYSTEMS WILL BRING PERIODIC CHANCES FOR LIGHT PRECIPITATION LATE THIS WEEK INTO THE WEEKEND. THURSDAY THROUGH FRIDAY NIGHT...VERY LIGHT RAIN OR DRIZZLE ASSOCIATED WITH ISENTROPIC LIFT UNDER THE SHORTWAVE EXITING TO THE EAST WILL BE HANDLED WITH VERY LOW POPS THU MORNING. BY AFTERNOON...A TRANSITORY MID LEVEL SHORTWAVE RIDGE THAT FOLLOWS SHOULD BRING CLEARING SKIES ALLOWING TEMPERATURES TO RECOVER INTO THE LOWER TO MID 60S. ANOTHER SHORTWAVE AND THE BROAD CYCLONIC FLOW ALOFT SHOULD BRING INCREASING CLOUDS OVERNIGHT...BUT WITH THE BEST FORCING WELL TO THE NORTH...WILL NOT ANTICIPATE ANY PRECIPITATION. CLOUD COVER SHOULD CONFINE MINS TO THE UPPER 30S TO LOWER 40S. THE NEXT SYSTEM BRUSHES PAST TO THE SOUTH LATE FRIDAY AND WILL HAVE SLIGHT CHANCE POPS FOR LIGHT RAIN ACROSS THE SOUTH FOR FRIDAY NIGHT. COLD ADVECTION GRADUALLY INCREASES THROUGH THIS PERIOD...AND BY FRIDAY NIGHT...850 MB TEMPERATURES NEAR TO BELOW ZERO CELSIUS ARE PROGGED OVER THE AREA. WILL THUS NEED DEEP MIXING TO REACH HIGHS IN THE 50S FRIDAY...THEN CLOUD COVER TO MAINTAIN LOWS IN THE MID TO UPPER 30S FRIDAY NIGHT. OVER THE WEEKEND...THE NEXT SHORTWAVE IS GENERALLY DEPICTED PASSING TO THE NORTH AROUND SATURDAY NIGHT...AND WILL MAINTAIN ONLY SLIGHT CHANCES FOR RAIN IN THE FAR NORTH. OTHERWISE...IMPROVING MODEL CONSISTENCY...BOTH FROM RUN TO RUN AND BETWEEN MODELS...SHOW 850 MB TEMPERATURES COOLING TO ZERO TO 4 BELOW BY SUNDAY SUPPORT WELL BELOW NORMAL SURFACE TEMPERATURES. ADVERTISED HIGHS IN THE 50S MAY BE TOO OPTIMISTIC...ESPECIALLY SUNDAY DEPENDING ON CLOUD TRENDS. LIKEWISE...CURRENT OVERNIGHT LOWS COULD POTENTIALLY BE COLD ENOUGH FOR A WIDESPREAD KILLING FREEZE...ESPECIALLY SUNDAY MORNING. HOWEVER...FOR NOW...WITH UNCERTAINTIES IN CLOUD COVER AND THE TIMING OF PASSING SURFACE RIDGE AXIS...LOWS WILL BE MAINTAINED IN THE 30S. NEXT WEEK...A CYCLONIC NW FLOW WITH PERIODIC SHORTWAVES AND REINFORCING SURFACE COLD FRONTS SETS UP OVER THE AREA THROUGH MOST OF THE WEEK. THERE IS HIGH CONFIDENCE THAT MUCH OF THE WEEK WILL FEATURE BELOW TO WELL BELOW NORMAL TEMPERATURES. HOWEVER... CHALLENGES WITH THE CRITICAL TIMING AND STRENGTH OF PASSING SHORTWAVES MAKES THIS A LOW PREDICTABILITY PATTERN THIS FAR OUT. FOR NOW...THERE IS ENOUGH CONSENSUS IN THE MODEL BLENDS TO PLACE LOW CHANCE POPS OVER MAINLY THE NORTH FOR SUNDAY NIGHT INTO MONDAY...AND THEN MORE WIDESPREAD HIGHER CHANCES FOR TUE INTO TUE NIGHT. THE LATEST GFS AND ECMWF INDICATE A STRONG SURGE OF COLD AIR BEHIND TUESDAY NIGHT/S COLD FRONT...THAT COULD LIMIT MIDWEEK HIGHS TO THE UPPER 30S OVER AT LEAST THE NORTH AND RESULT IN WIDESPREAD 20S FOR LOWS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 639 AM CDT WED OCT 16 2013 CYCLONIC FLOW AROUND LOW PRESSURE OVER LAKE HURON WILL KEEP MVFR CIGS OVER THE AREA FOR THE REST OF THE TODAY. THERE IS A NARROW BAND OF IFR CIGS OVER NORTHERN IOWA WITH THE SOUTHERN EDGE WAS AS FAR SOUTH AS HIGHWAY 20. THESE LOW CIGS COULD SAG SOUTH INTO THE HWY 30 CORRIDOR YET THIS MORNING. THE IFR CIGS WILL BE ACCOMPANIED BY SOME PATCHY DRIZZLE WITH VSBYS IN THE 3 TO 5SM RANGE. THE LOWER CIGS SHOULD LIFT ABOVE 1000 FT BY LATE MORNING OR EARLY AFTERNOON. THERE IS UNCERTAINTY ABOUT CEILING TRENDS LATE TONIGHT WITH THE 06Z MODELS RUNS SUGGESTING SOME CLEARING WILL TAKE PLACE AFTER MIDNIGHT. FOR NOW MAINTAINED CIGS AROUND 3000 FT AT ALL TAF SITES THROUGH 12Z AND WAIT TO SEE IF LATER RUNS CONTINUE THE TREND OF FASTER CLEARING. IF THERE IS SOME CLEARING OVERNIGHT THEN THERE IS POTENTIAL FOR FOG DEVELOPMENT. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...08 SYNOPSIS...DLF SHORT TERM...DLF LONG TERM...SHEETS AVIATION...DLF
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1213 AM CDT Wed Oct 16 2013 ...Updated synopsis and aviation discussion... .SYNOPSIS... ISSUED AT 1210 AM CDT WED OCT 16 2013 At 00z Wednesday -22c 500mb low was located near the four corners region. This was near the based of an upper level trough that extended from the southwest United States to the western Great Lakes. A 500mb ridge axis extended from south central Canada into the Pacific Northwest. At the 700mb level temperatures this morning across the central plains ranged from -10c at North Platte to -1c at Dodge City to +3c at Amarillo. At the 850mb level a pools of higher dewpoints were observed across southern Nebraska and northern Kansas with temperatures ranging from +4c at Dodge City to -1c at North Platte and Omaha. Satellite loop also indicating some lower cloud cover was occurring in this area of higher 850mb dewpoints earlier this morning with Goodland reporting a cloud bases at 3600ft and Hays reporting clouds at 4100ft. At the surface an area of high pressure was located over southeast Wyoming with light winds near the surface ridge axis that extending southeast of the high into western Kansas. && .SHORT TERM...(This evening through Wednesday) ISSUED AT 153 PM CDT TUE OCT 15 2013 To start off with, I deliberated over low temperatures quite a bit for tonight, and the resultant freeze and frost hazards. Model guidance varies quite a bit, and this difference seems to be centered around how fast some mid and high clouds will intrude. Have settled upon using the HRRR and RUC models, which are a bit cooler than then NAM, ECMWF, and GFS models. In the end, there could be a small area that freezes tonight in our northwest zones, namely Trego, Ellis, Scott, Lane and Ness counties, where a freeze warning will be posted from 4 am to 9 am CDT. The 32F degree mark may be tricky in Scott county, if the mid level clouds get there before the diurnal cooling off occurs, they may hit 33F or 34F very briefly around 09-10Z. To the south, surrounding the Freeze Warning, mid 30s seem likely and a frost advisory is in place from 4 am to 9 am CDT, with widespread frost mentioned. Even one more tier of counties southward will have patchy frost mentioned late, but without an advisory. Down along most of the Oklahoma state boundary, clouds will be entering there sooner, and thus lows in the upper 30s will extend along most of that stretch. An upper wave, open in nature, will cross from New Mexico into southeast Kansas on Wednesday. The upper synoptic lift may be just enough to kick off a few rain showers across our southern half of the CWA, but only slight chances seem justified since no surface boundary is present, and the lower layers will be cool. With clouds, some scattered showers, and cold air advection, max temps will struggle to get out of the 50s. Current forecast max temps range from 57F in Syracuse, to 60F in Medicine Lodge. I did not change the forecast highs, as they seemed reasonable. The other weather parameter worth noting is winds will not be too strong, as they have been of late. The high pressure will produce northwest winds around 10 mph in the morning, which will shift to the west by afternoon, still blow in the 10 to 15 mph range. .LONG TERM...(Wednesday night through Tuesday) ISSUED AT 316 PM CDT TUE OCT 15 2013 Relatively dry and sunny conditions are expected Thursday due to transient mid level shortwave ridging. Cold temperatures in the mid to upper 30`s are most likely during the morning while abundant insolation should allow warming into the 60`s by early afternoon. a sharp mid to upper level baroclinic zone associated with a strongly positively tilted trough and 300 mb level polar will jet have create sensible weather impacts for Friday. As the upper trough approaches and sharpens by Friday morning, the mid level baroclinic zone will strengthen causing frontogenesis and associated lift ageostrophic lifting. GFS is very similar to the ECMWF with respect to most mass fields with this system, and shows a continuously sloping intense frontogenetic profile from above 850 mb level near medicine lodge to near 500 mb across NW Kansas. This cold system aloft appears warm enough in the boundary layer to expect phase change to all rain at the surface. GFS and GEM are the coldest of the models, only allowing for temperatures to reach the upper 40`s across western Kansas by the afternoon. Precipitation chances have been increased to the likely category for Friday morning with a rapid tapering in the afternoon as the upper trough transitions to a subsident northwest flow across central Kansas by Friday night. Saturday morning will have potential to be cold again (even with frost) if winds and clearing conditions are favorable, but yet uncertain considering it is still at a 96 hour forecast timestep. The remainder of the forecast period through early next week is for and only slowly moderating surface temperatures toward normal for mid October, as northwest flow aloft becomes established aloft and high pressure dominates the central Rockies into the southern plains. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) ISSUED AT 1210 AM CDT WED OCT 16 2013 00Z Model runs continue to indicate increasing clouds across western Kansas overnight. Latest bufr soundings suggest cloud bases will between 3000ft and 4000ft AGL at HYS with 5000ft to 8000ft ft AGL at DDC and GCK. These VFR cigs are forecast to linger across western Kansas through late day as an upper level trough moves east across the central high plains. Northwest winds at 10kts or less will gradually back to the west by evening as an area of high pressure at the surface moves across western Kansas. && .PRELIMINARY POINT TEMPS/POPS... DDC 36 65 39 50 / 10 10 40 70 GCK 34 64 39 51 / 10 10 40 70 EHA 38 64 37 50 / 0 10 30 60 LBL 36 66 39 51 / 0 10 40 70 HYS 35 63 39 52 / 10 10 30 60 P28 38 67 42 54 / 10 0 40 70 && .DDC WATCHES/WARNINGS/ADVISORIES... FROST ADVISORY from 4 AM CDT /3 AM MDT/ to 9 AM CDT /8 AM MDT/ this morning FOR KSZ046-061>065-074>079. FREEZE WARNING from 4 AM to 9 AM CDT this morning FOR KSZ030-031- 043>045. && $$ SYNOPSIS...Burgert SHORT TERM...Burke LONG TERM...Russell AVIATION...Burgert
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
247 PM EDT WED OCT 16 2013 .UPDATE... ISSUED AT 235 PM EDT WED OCT 16 2013 HOURLY GRIDS WERE FRESHENED UP BASED ON RECENT RADAR AND OBSERVATION TRENDS. MAX T HAS LIKELY ALREADY BEEN REACHED IN THE EASTERN PAR OF THE CWA AND LOCATIONS IN THE CUMBERLAND VALLEY AND NEAR THE TN BORDER WILL PROBABLY ONLY CLIMB ANOTHER COUPLE OF DEGREES AT THE MOST. SHOWER ACTIVITY ACTIVITY SHOULD INCREASE A BIT IN THE EVENING...WITH SHOWERS ANTICIPATED TO BE MORE WIDESPREAD...ESPECIALLY SOUTHEAST CWA LATE TONIGHT AND ON THURSDAY. UPDATE ISSUED AT 1055 AM EDT WED OCT 16 2013 ISOLATED TO SCATTERED SHOWERS CONTINUE TO WORK ACROSS EASTERN KY WITH TRACE OR GENERALLY LIGHT RAINFALL SO FAR OF A FEW HUNDREDTHS OF AN INCH...IF THAT. THE SHORT TERM MODELS...ESPECIALLY THE HRRR POINT TOWARD THE NEXT WAVE NOW OVER MIDDLE AND WESTERN TN TO WORK INTO THE AREA THIS AFTERNOON...AFFECTING THE SW PART OF THE ARE IN PARTICULAR. WITH THE DENSE CLOUD COVER SO FAR...TEMPS WERE RUNNING BEHIND THE PREVIOUS FORECAST IN THEIR CLIMB THIS MORNING. WITH THAT IN MIND...HOURLY TEMPS AS WELL AS MAX T WERE ADJUSTED DOWN A FEW DEGREES ACROSS THE BOARD. THE INCOMING MET MOS GUIDANCE SUPPORTS THIS CHANGE AS WELL. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 402 AM EDT WED OCT 16 2013 SHOWERS CONTINUE TO SKIRT ALONG THE EDGE OF THE CWA...COVERING PORTIONS OF CENTRAL KY...BUT REMAINING VERY LIGHT IN NATURE. IN FACT...MOST STATIONS ALONG THE CENTRAL PORTION OF THE STATE ARE NOT EVEN PICKING UP ANY MEASURABLE PRECIP. AS SUCH...EXPECT SHOWERS TO MAKE THEIR WAY INTO THE CWA OVER THE NEXT COUPLE OF HOURS...WHILE REMAINING LIGHT IN NATURE. LATEST HI-RES MODELS SHOW PRECIP INTENSIFYING IN COVERAGE DURING THE DAY TIME HOURS...AS THE LINE MAKES IT/S WAY EASTWARD ACROSS THE STATE. DON/T EXPECT MORE THAN A QUARTER INCH OF ACCUMULATION BY 6Z TONIGHT. THE COLD FRONT FOR WHICH THIS PRECIP IS ASSOCIATED WITH WILL PUSH INTO EASTERN KY BY 18Z TODAY. AS IT PASSES...PLACES ACROSS CENTRAL KY...AND POSSIBLY OUR FAR NORTHERN COUNTIES...CAN EXPECT SOME BRIEF CLEARING AS DRIER AIR FILTERS IN. HOWEVER...BY 0Z THIS EVENING...THE FRONT WILL STALL OUT ACROSS THE FAR EASTERN CWA...PIVOTING SOUTHWARD BUT MAKING NO EASTWARD PROGRESSION. THIS WILL KEEP A PULL OF MOISTURE FROM THE ATLANTIC INTO THE APPALACHIAN REGION...AND ENOUGH ISENTROPIC LIFT TO ALLOW LIKELY SHOWERS TO CONTINUE/REDEVELOP ACROSS MUCH OF THE CWA. AN ADDITIONAL QUARTER TO HALF INCH IS POSSIBLE IN SOME LOCATIONS IN THE CWA...MAINLY THE FAR SOUTHEASTERN FRINGES OF THE STATE. THE FRONT WILL THEN FINALLY CONTINUE TO THE SE STARTING 12Z THURSDAY...ALLOWING HIGH PRESSURE TO FINALLY TAKE IT/S PLACE ACROSS STATE THROUGH THE DAY. THE LAST OF THE PRECIP WILL MOVE OUT DURING THE AFTERNOON HOURS...WITH SKIES CLEARING A COUPLE HOURS BEHIND. AS FOR TEMPERATURES...STILL EXPECTING HIGHS TODAY IN THE UPPER 60S TO LOW 70S...WITH THE WARMEST TEMPERATURES BEING FELT ACROSS THE FAR EAST WHERE THE BETTER RAIN CHANCES WILL HOLD OFF THE LONGEST. WITH THE COLD FRONT STALLING AND PIVOTING OVERNIGHT...CLEARING WILL NOT BE AS FAST TO COME AS IN PREVIOUS FORECAST...SO EXPECT MOST OF THE REGION WILL REMAIN IN THE LOW TO MID 50S. THE EXCEPTION WILL BE THE FAR NW SECTION OF THE CWA...WHERE /AS MENTIONED ABOVE/ THE SOUTHWARD PIVOTING WILL BRING IN A BRIEF TIME OF CLEARING BEFORE MOISTURE MOVES BACK IN. LOWS HERE WILL BE SLIGHTLY COOLER...IN THE UPPER 40S. AS FOR HIGHS TOMORROW...RAISED THEM SLIGHTLY COMPARED TO PREVIOUS...DUE TO THE FACT THAT THE MOISTURE AND CLOUDS FROM THE STALLED FRONT WILL STICK AROUND LONGER AND THUS PREVENT COOLER AND DRIER AIR FROM MOVING IN. ONCE FRONT STARTS PROGRESSING EASTWARD DURING THE AFTERNOON...TEMPERATURES WILL BEGIN THEIR DESCENT. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 340 AM EDT WED OCT 16 2013 THE MODELS CONTINUE TO HAVE PROBLEMS RESOLVING THE EVOLUTION OF A DEEP MID-LEVEL TROUGH OVER THE NORTH CENTRAL PART OF THE COUNTRY LATER THIS WEEKEND. HOWEVER...A QUICK GLANCE AT THE LATEST ECMWF SUGGESTS THAT THERE MAY BE SOME GROWING CONSENSUS AS IT HAS BACKED OFF ITS MORE AMPLIFIED 12Z VERSION OF THE TROUGH. THE DEPARTURE OF A SMALL...BUT POTENT WAVE AT THE START OF THE EXTENDED WILL LEAVE BEHIND FAST...AND RATHER QUIET...SOUTHWEST FLOW OVER THE LOWER OHIO VALLEY INTO THE START OF THE WEEKEND BEFORE A DEEP TROUGH PUSHES EAST FROM THE HIGH PLAINS AND SWEEPS OVER THE AREA. THE BULK OF ITS ENERGY WILL LIFT NORTH INTO THE GREAT LAKES BY 00Z SUNDAY AS HEIGHTS FALL IN ITS WAKE THROUGHOUT THE OHIO VALLEY. VARIOUS WEAKER WAVES WILL THEN PASS THROUGH THE REGION IN GENERAL FAST AND FLAT FLOW. SOME AMPLIFICATION WILL TAKE PLACE LATER MONDAY AS MORE ENERGY POURS INTO THE NORTHERN PLAINS AND THE DEEPER MID CONTINENTAL TROUGH BEGINS TO BECOME REESTABLISHED TO THE NORTH OF THE CWA. GIVEN THE RECENT TROUBLES IN THE MODELS WITH THIS PATTERN WILL CONTINUE TO RESERVE JUDGMENT ON INDIVIDUAL SOLUTIONS AND FAVOR A GENERAL BLEND FOR THE EXTENDED. SENSIBLE WEATHER WILL FEATURE A RELATIVELY DRY...IF SOMEWHAT COOL... EXTENDED AS WEAK HIGH PRESSURE PASSES THROUGH THE AREA UP TO THE START OF THE WEEKEND. A DECENT FRONT WILL CROSS EAST KENTUCKY ON SATURDAY...BUT LOOKS TO BE MOISTURE STARVED WITH THE QPF MAINLY MISSING US TO THE NORTH AND ALSO SOUTH. WILL KEEP A SMALL CHANCE OF POPS IN FOR A SATURDAY AFTERNOON FROPA WITH THIS. ANOTHER WEAK HIGH PRESSURE AREA WILL MOVE INTO THE STATE FOR THE START OF THE NEW WORK WEEK...THOUGH THE NEXT FRONT MAY SNEAK INTO THE NORTHERN EXTENT OF THE CWA ON TUESDAY IN ASSOCIATION WITH THE RESURGENCE OF THE BROAD MID LEVEL TROUGH. THE CR GRID LOAD CAME IN DECENT ENOUGH GIVEN THE COMPROMISE PREFERRED ABOVE WITH LITTLE POP OR SKY ADJUSTMENTS NEEDED. AGAIN WENT WITH SOME SMALL RIDGE AND VALLEY ADJUSTMENTS TO LOW TEMPS FOR THURSDAY AND FRIDAY NIGHTS AS WELL AS SUNDAY AND MONDAY NIGHT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 238 PM EDT WED OCT 16 2013 A COLD FRONT...WILL CONTINUE TO SLOWLY TREK EASTWARD INTO EASTERN KY EARLY IN THE PERIOD. AHEAD OF THIS BOUNDARY IN SHOWERS AND DRIZZLE...CIGS HAVE DROPPED TO MVFR OR LOWER WITH IFR AND AT TIMES LOWER CIGS RECENTLY REPORTED WEST OF AN SJS TO CPF TO IOB LINE. THIS INCLUDES ALL OF THE TAF SITES. THE FRONT WILL THEN STALL OVER EASTERN KY OVERNIGHT AND PIVOT SOUTHWARD SLIGHTLY. THIS WILL LEAD TO CONTINUED CHANCES FOR RAIN ACROSS THE TAF SITES THROUGH THE NIGHT AND INTO TOMORROW MORNING. BETWEEN 2Z AND 9Z A RELATIVE LULL IN PRECIP CHANCES IS EXPECTED WITH ANY IMPROVEMENT OF CIGS INTO THE VFR RANGE SHORT LIVED AS THE NEXT WAVE SHOULD BRING ANOTHER ROUND OF SHOWERS AND CIGS TO IFR OR EVEN TO AIRPORT MINS LATE IN THE PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JP SHORT TERM...JMW LONG TERM...GREIF AVIATION...JP
AREA FORECAST DISCUSSION
NWS JACKSON KY
1129 AM EDT WED OCT 16 2013 .UPDATE... ISSUED AT 1055 AM EDT WED OCT 16 2013 ISOLATED TO SCATTERED SHOWERS CONTINUE TO WORK ACROSS EASTERN KY WITH TRACE OR GENERALLY LIGHT RAINFALL SO FAR OF A FEW HUNDREDTHS OF AN INCH...IF THAT. THE SHORT TERM MODELS...ESPECIALLY THE HRRR POINT TOWARD THE NEXT WAVE NOW OVER MIDDLE AND WESTERN TN TO WORK INTO THE AREA THIS AFTERNOON...AFFECTING THE SW PART OF THE ARE IN PARTICULAR. WITH THE DENSE CLOUD COVER SO FAR...TEMPS WERE RUNNING BEHIND THE PREVIOUS FORECAST IN THEIR CLIMB THIS MORNING. WITH THAT IN MIND...HOURLY TEMPS AS WELL AS MAX T WERE ADJUSTED DOWN A FEW DEGREES ACROSS THE BOARD. THE INCOMING MET MOS GUIDANCE SUPPORTS THIS CHANGE AS WELL. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 402 AM EDT WED OCT 16 2013 SHOWERS CONTINUE TO SKIRT ALONG THE EDGE OF THE CWA...COVERING PORTIONS OF CENTRAL KY...BUT REMAINING VERY LIGHT IN NATURE. IN FACT...MOST STATIONS ALONG THE CENTRAL PORTION OF THE STATE ARE NOT EVEN PICKING UP ANY MEASURABLE PRECIP. AS SUCH...EXPECT SHOWERS TO MAKE THEIR WAY INTO THE CWA OVER THE NEXT COUPLE OF HOURS...WHILE REMAINING LIGHT IN NATURE. LATEST HI-RES MODELS SHOW PRECIP INTENSIFYING IN COVERAGE DURING THE DAY TIME HOURS...AS THE LINE MAKES IT/S WAY EASTWARD ACROSS THE STATE. DON/T EXPECT MORE THAN A QUARTER INCH OF ACCUMULATION BY 6Z TONIGHT. THE COLD FRONT FOR WHICH THIS PRECIP IS ASSOCIATED WITH WILL PUSH INTO EASTERN KY BY 18Z TODAY. AS IT PASSES...PLACES ACROSS CENTRAL KY...AND POSSIBLY OUR FAR NORTHERN COUNTIES...CAN EXPECT SOME BRIEF CLEARING AS DRIER AIR FILTERS IN. HOWEVER...BY 0Z THIS EVENING...THE FRONT WILL STALL OUT ACROSS THE FAR EASTERN CWA...PIVOTING SOUTHWARD BUT MAKING NO EASTWARD PROGRESSION. THIS WILL KEEP A PULL OF MOISTURE FROM THE ATLANTIC INTO THE APPALACHIAN REGION...AND ENOUGH ISENTROPIC LIFT TO ALLOW LIKELY SHOWERS TO CONTINUE/REDEVELOP ACROSS MUCH OF THE CWA. AN ADDITIONAL QUARTER TO HALF INCH IS POSSIBLE IN SOME LOCATIONS IN THE CWA...MAINLY THE FAR SOUTHEASTERN FRINGES OF THE STATE. THE FRONT WILL THEN FINALLY CONTINUE TO THE SE STARTING 12Z THURSDAY...ALLOWING HIGH PRESSURE TO FINALLY TAKE IT/S PLACE ACROSS STATE THROUGH THE DAY. THE LAST OF THE PRECIP WILL MOVE OUT DURING THE AFTERNOON HOURS...WITH SKIES CLEARING A COUPLE HOURS BEHIND. AS FOR TEMPERATURES...STILL EXPECTING HIGHS TODAY IN THE UPPER 60S TO LOW 70S...WITH THE WARMEST TEMPERATURES BEING FELT ACROSS THE FAR EAST WHERE THE BETTER RAIN CHANCES WILL HOLD OFF THE LONGEST. WITH THE COLD FRONT STALLING AND PIVOTING OVERNIGHT...CLEARING WILL NOT BE AS FAST TO COME AS IN PREVIOUS FORECAST...SO EXPECT MOST OF THE REGION WILL REMAIN IN THE LOW TO MID 50S. THE EXCEPTION WILL BE THE FAR NW SECTION OF THE CWA...WHERE /AS MENTIONED ABOVE/ THE SOUTHWARD PIVOTING WILL BRING IN A BRIEF TIME OF CLEARING BEFORE MOISTURE MOVES BACK IN. LOWS HERE WILL BE SLIGHTLY COOLER...IN THE UPPER 40S. AS FOR HIGHS TOMORROW...RAISED THEM SLIGHTLY COMPARED TO PREVIOUS...DUE TO THE FACT THAT THE MOISTURE AND CLOUDS FROM THE STALLED FRONT WILL STICK AROUND LONGER AND THUS PREVENT COOLER AND DRIER AIR FROM MOVING IN. ONCE FRONT STARTS PROGRESSING EASTWARD DURING THE AFTERNOON...TEMPERATURES WILL BEGIN THEIR DESCENT. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 340 AM EDT WED OCT 16 2013 THE MODELS CONTINUE TO HAVE PROBLEMS RESOLVING THE EVOLUTION OF A DEEP MID-LEVEL TROUGH OVER THE NORTH CENTRAL PART OF THE COUNTRY LATER THIS WEEKEND. HOWEVER...A QUICK GLANCE AT THE LATEST ECMWF SUGGESTS THAT THERE MAY BE SOME GROWING CONSENSUS AS IT HAS BACKED OFF ITS MORE AMPLIFIED 12Z VERSION OF THE TROUGH. THE DEPARTURE OF A SMALL...BUT POTENT WAVE AT THE START OF THE EXTENDED WILL LEAVE BEHIND FAST...AND RATHER QUIET...SOUTHWEST FLOW OVER THE LOWER OHIO VALLEY INTO THE START OF THE WEEKEND BEFORE A DEEP TROUGH PUSHES EAST FROM THE HIGH PLAINS AND SWEEPS OVER THE AREA. THE BULK OF ITS ENERGY WILL LIFT NORTH INTO THE GREAT LAKES BY 00Z SUNDAY AS HEIGHTS FALL IN ITS WAKE THROUGHOUT THE OHIO VALLEY. VARIOUS WEAKER WAVES WILL THEN PASS THROUGH THE REGION IN GENERAL FAST AND FLAT FLOW. SOME AMPLIFICATION WILL TAKE PLACE LATER MONDAY AS MORE ENERGY POURS INTO THE NORTHERN PLAINS AND THE DEEPER MID CONTINENTAL TROUGH BEGINS TO BECOME REESTABLISHED TO THE NORTH OF THE CWA. GIVEN THE RECENT TROUBLES IN THE MODELS WITH THIS PATTERN WILL CONTINUE TO RESERVE JUDGMENT ON INDIVIDUAL SOLUTIONS AND FAVOR A GENERAL BLEND FOR THE EXTENDED. SENSIBLE WEATHER WILL FEATURE A RELATIVELY DRY...IF SOMEWHAT COOL... EXTENDED AS WEAK HIGH PRESSURE PASSES THROUGH THE AREA UP TO THE START OF THE WEEKEND. A DECENT FRONT WILL CROSS EAST KENTUCKY ON SATURDAY...BUT LOOKS TO BE MOISTURE STARVED WITH THE QPF MAINLY MISSING US TO THE NORTH AND ALSO SOUTH. WILL KEEP A SMALL CHANCE OF POPS IN FOR A SATURDAY AFTERNOON FROPA WITH THIS. ANOTHER WEAK HIGH PRESSURE AREA WILL MOVE INTO THE STATE FOR THE START OF THE NEW WORK WEEK...THOUGH THE NEXT FRONT MAY SNEAK INTO THE NORTHERN EXTENT OF THE CWA ON TUESDAY IN ASSOCIATION WITH THE RESURGENCE OF THE BROAD MID LEVEL TROUGH. THE CR GRID LOAD CAME IN DECENT ENOUGH GIVEN THE COMPROMISE PREFERRED ABOVE WITH LITTLE POP OR SKY ADJUSTMENTS NEEDED. AGAIN WENT WITH SOME SMALL RIDGE AND VALLEY ADJUSTMENTS TO LOW TEMPS FOR THURSDAY AND FRIDAY NIGHTS AS WELL AS SUNDAY AND MONDAY NIGHT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 657 AM EDT WED OCT 16 2013 A COLD FRONT...CURRENTLY LOCATED ACROSS WEST-CENTRAL KY...WILL CONTINUE TO SLOWLY TREK EASTWARD INTO EASTERN KY THROUGH THE DAY. A BAND OF PRECIPITATION ALONG AND AHEAD OF THIS FRONT CONTINUES TO INCH IT/S WAY TOWARD EASTERN KY...WITH A FEW ISOLATED RETURNS POPPING UP ACROSS THE JKL CWA BORDER. SO FAR THESE SHOWERS HAVE BEEN FAIRLY LIGHT...WITH LITTLE TO NO ACCUMULATION. OVER THE NEXT FEW HOURS...EXPECT THESE SHOWERS TO CONTINUE EASTWARD AND BEGIN IMPACTING THE TAF SITES...INCREASING SLIGHTLY IN INTENSITY. AS OF NOW...MAIN CATEGORY RESTRICTIONS SHOULD COME IN THE FORM OF LOWERING MVFR CIGS RATHER THAN VISIBILITY. FRONT WILL THEN STALL OVER EASTERN KY OVERNIGHT AND PIVOT SOUTHWARD SLIGHTLY. THIS WILL LEAD TO CONTINUED CHANCES FOR RAIN ACROSS THE TAF SITES THROUGH THE NIGHT AND INTO TOMORROW MORNING. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JP SHORT TERM...JMW LONG TERM...GREIF AVIATION...JMW
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1011 PM EDT THU OCT 17 2013 .SYNOPSIS... LOW PRESSURE WILL APPROACH FROM THE SOUTHWEST LATE TONIGHT AND THEN CROSS THE REGION FRIDAY. A COLD FRONT WILL APPROACH LATER SATURDAY THEN CROSS THE REGION SUNDAY. && .NEAR TERM /THROUGH FRIDAY/... 930 PM UPDATE: WE MADE ADDITIONAL ADJUSTMENTS WITH CLD CVR AND POPS. WITH CLD CVR...WE INCREASED CLD CVR OVR DOWNEAST AREAS BASED ON OBSCD CLGS WITH FOG OVR THIS PTN OF THE FA. WITH POPS...WE INCREASED TMG OF SHWRS ABT AN HR OR TWO IN THE 06-12Z TMG. LATEST 18Z GFS AND 00Z HRRR GUIDANCE INDICATES VERY RAPID PROGRESSION...AT ABT 50 TO 60 MPH...OF THE RNFL CURRENTLY OVR NRN NY STATE AND XTRM SW QB...REACHING FAR SW PTNS OF THE FA BY 2-3 AM EDT AND ECLIPSING FAR NE PTNS OF THE FA BY 12Z. LASTLY WE LOWERED OVRNGT LOWS A DEG OR TWO...SPCLY NW PTNS OF THE FA WITH SOME CLRG RESULTING IN IN WEAK RADITIONAL COOLING. THE FORWARD EDGE OF THE MID CLD CANOPY SHOULD REACH WRN PTNS OF THE FA WITH THE NEXT COUPLE OF HRS OR SO... STEADYING TEMPS ATTM. REST OF OVRNGT LOW TEMPS ACROSS THE FA STILL LOOK REASONABLE ATTM. 630 PM UPDATE: POPS WERE ADJUSTED FOR AN INITIALLY SLOWER ONSET FOR THE LATE EVE INTO THE OVRNGT HRS...THEN MERGING TO THE CATEGORICAL POPS SLATED FOR FRI FROM THE AFTN FCST UPDATE. THIS CHG WAS MADE UTILIZING THE POPS FROM QPF TOOL. OTHERWISE...MINOR CHGS WERE MADE TO SKY CVR THIS EVE AND TO FCST HRLY TEMPS BASED ON 6 PM SAT IMAGERY AND SFC OBS. ORGNL DISC: LOW PRESSURE WILL TRACK FROM THE MID ATLANTIC REGION TO SOUTHERN MAINE TONIGHT. PARTLY/MOSTLY CLOUDY SKIES ARE EXPECTED ACROSS THE REGION EARLY TONIGHT. CLOUD COVER WILL THEN INCREASE ACROSS THE REGION OVERNIGHT...WITH INCREASING RAIN CHANCES LATE. THE LOW WILL CROSS THE REGION FRIDAY MORNING WITH AN AREA OF RAIN CROSSING THE FORECAST AREA. THE LOW WILL EXIT NORTHEAST ACROSS THE MARITIMES FRIDAY AFTERNOON...WITH SHOWERS ENDING IN THE WAKE OF THE LOW. SKIES WILL REMAIN MOSTLY CLOUDY ACROSS NORTHERN AREAS FRIDAY AFTERNOON...WITH DECREASING CLOUDS DOWNEAST. LOW TEMPERATURES TONIGHT WILL RANGE FROM THE MID 40S NORTH...TO THE UPPER 40S TO AROUND 50 DOWNEAST. HIGH TEMPERATURES FRIDAY WILL RANGE FROM THE LOWER TO MID 50S NORTH...TO THE UPPER 50S TO AROUND 60 DOWNEAST. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/... COOLER AIR FOLLOWS THE LOW PRESSURE SYSTEM FOR FRIDAY NIGHT...BUT WINDS AND CLOUD COVER ARE EXPECTED TO PREVENT TEMPERATURES FROM FALLING DRAMATICALLY. LOWS WILL BE IN THE LOW 40S. A TRANSIENT RIDGE OF HIGH PRESSURE BUILDS SATURDAY WITH WARM ADVECTION. THE PRIMARY CHALLENGE FOR SATURDAY WILL BE CLOUD COVER DUE TO STRATOCUMULUS IN NORTHERN ZONES DURING THE AFTERNOON AND HIGH CLOUDS INCREASING ACROSS THE ENTIRE FORECAST AREA BY LATE MORNING WITH A STRONG UPPER JET MOVING THROUGH THE AREA. THE GENERAL TREND WILL BE SUNSHINE IN THE MORNING AND CLOUDY CONDITIONS IN THE AFTERNOON. A LIGHT AFTERNOON RAIN SHOWER MAY EVEN BE POSSIBLE IN NORTH OF HOULTON DUE TO MODEST INSTABILITY UNDER H700. HIGHS WILL BE MOSTLY IN THE UPPER 50S TO LOW 60S. THE NEXT SHORTWAVE WILL ROTATE AROUND THE BROAD UPPER TROUGH IN ONTARIO AND APPROACH LATER SATURDAY NIGHT. THIS WILL BRING ANOTHER ROUND OF RAIN THAT WILL CONTINUE INTO SUNDAY MORNING. AM EXPECTING CLOUDS TO INCREASE WELL BEFORE DAWN AND WILL GO WITH LOW TO MID 40S. HAVE INCREASED THE POPS TO LIKELY FOR SUNDAY MORNING. CONFIDENCE IN THE SPEED OF THE SYSTEM IS NOT HIGH. TEND TO FAVOR A COMPROMISE TOWARDS THE 17/00Z ECMWF WHICH MOVES THE TROUGH OUT BY THE AFTERNOON. THE TROUGH MAY STRENGTHEN AS IT MOVES INTO NORTHERN MAINE AS THE UPPER TROUGH SHARPENS AND BECOMES NEGATIVELY TILTED. BEHIND THE FRONT...THE COLDEST AIR MASS OF THE SEASON WILL ARRIVE FOR NEXT WEEK. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... ACTIVE PATTERN WILL CONTINUE INTO THE LONG TERM. SHOWERS WILL BE POSSIBLE ACROSS THE FAR NORTHWEST TO BEGIN THE PERIOD. INCREASED CHANCES OF SHOWERS AREA WIDE GOING INTO TUESDAY AS WARM FRONT LIFTS NORTH. THESE SHOWER CHANCES WILL CONTINUE TO INCREASE OVERNIGHT TUESDAY AS UPPER LEVEL LOW AND SURFACE LOW CONTINUE TO MOVE NORTH AND EAST ACROSS QUEBEC. CHANCES OF SHOWERS WILL CONTINUE MAINLY ACROSS THE NORTHERN PORTIONS OF THE REGION AS THE SURFACE LOW PRESSES NORTH WEDNESDAY. COLDER AIR WILL PROGRESS SOUTH UNDER NORTHWEST FLOW WEDNESDAY NIGHT INTO THURSDAY. LIGHT WRAP AROUND SHOWERS WILL BE POSSIBLE ACROSS THE NORTH WITH IMPROVING CONDITIONS ALONG THE COAST AND DOWNEAST THURSDAY. TEMPERATURES THROUGH THE PERIOD WILL BE NEAR NORMAL. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... NEAR TERM: OCCASIONAL MVFR CONDITIONS ARE POSSIBLE ACROSS NORTHERN AREAS EARLY TONIGHT...WITH OCCASIONAL MVFR/IFR CONDITIONS POSSIBLE ALONG THE DOWNEAST COAST. CONDITIONS WILL THEN LOWER TO IFR/LIFR LEVELS ACROSS THE ENTIRE FORECAST AREA OVERNIGHT...WITH SIMILAR CONDITIONS PERSISTING EARLY FRIDAY. CONDITIONS WILL IMPROVE TO VFR LEVELS ACROSS MUCH OF THE REGION FRIDAY AFTERNOON...THOUGH OCCASIONAL MVFR CONDITIONS COULD PERSIST ACROSS NORTHERN AREAS. SHORT TERM: VFR WILL BE THE PREDOMINANT CONDITION FRIDAY NIGHT INTO SATURDAY NIGHT. CONDITIONS WILL DROP TO MVFR TEMPO IFR LATER SATURDAY NIGHT INTO SUNDAY MORNING. CONDITIONS WILL RETURN TO VFR FOR BGR AND BHB IN THE AFTERNOON...BUT MVFR CEILINGS MAY LINGER NORTH OF HUL. MVFR POSSIBLE IN HEAVIER SHOWERS TUESDAY. && .MARINE... NEAR TERM: WINDS/SEAS ARE EXPECTED TO BE BELOW SMALL CRAFT ADVISORY LEVELS TONIGHT INTO EARLY FRIDAY. SEAS ARE THEN EXPECTED TO BUILD TO SMALL CRAFT ADVISORY LEVELS FRIDAY AFTERNOON. A SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS IS IN EFFECT STARTING FRIDAY AFTERNOON FOR MUCH OF THE WATERS...WITH THE EXCEPTION OF THE INTRACOASTAL WATERS. VISIBILITIES WILL BE REDUCED IN FOG AND RAIN TONIGHT INTO FRIDAY. SHORT TERM: WAVE HTS ARE EXPECTED TO REACH SMALL CRAFT ADVISORY CRITERIA THROUGH FRIDAY NIGHT WITH SEAS AROUND 6 FEET IN THE OUTER WATERS. ALTHOUGH WIND GUSTS MAY REACH 20 KTS AT TIMES THROUGH THE WEEKEND...THE BEST CHANCE FOR THE NEXT SCA WILL BE LATE SUNDAY BEHIND THE COLD FRONT. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 2 PM FRIDAY TO 6 AM EDT SATURDAY FOR ANZ050-051. && $$ NEAR TERM...VJN SHORT TERM...MCW LONG TERM...JORDAN AVIATION...VJN/MCW MARINE...VJN/MCW
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
1018 AM EDT WED OCT 16 2013 .SYNOPSIS... A STALLED FRONT TO OUR SOUTH WILL GRADUALLY RETURN NORTH AS A WARM FRONT LATE TONIGHT AND WEDNESDAY. A COLD FRONT WILL APPROACH FROM THE GREAT LAKES WEDNESDAY NIGHT THEN CROSS THE AREA ON THURSDAY. WEAK LOW PRESSURE CROSSES THE AREA FRIDAY AND AGAIN ON SUNDAY BRINGING WIDESPREAD SHOWERS TO THE REGION. A WARM FRONT APPROACHES ON MONDAY WHILE HIGH PRESSURE TRIES TO BUILD IN FROM THE SOUTH. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... .UPDATE...CLOUD COVER WAS ADJUSTED SLIGHTLY TO ACCOUNT FOR A FEW CLEAR SPOTS THAT ARE NOW CLOSING UP. STRATUS IS HOLDING TIGHT AND SHOULD CONTINUE THROUGHOUT THE DAY. AREA OF RAIN OFFSHORE WILL GRADUALLY SPREAD NORTH TOWARDS THE MIDCOAST TODAY. ADDED HIGHER POPS FOR ISLANDS AND OFFSHORE AREAS. && PREVIOUS DISCUSSION...WARM FNT LIFTING INTO THE REGION WILL BRING A DREARY START TO THE DAY. WEAK ONSHORE FLOW AND NEARLY SATURATED LOW LVLS WILL BRING STRATUS INTO COASTAL AREAS EARLY. WEAK WAA ALOFT WILL PROVIDE ENOUGH LIFT FOR SOME DZ IN THESE AREAS THRU SUNRISE. DAYTIME HEATING WILL EVENTUALLY HELP LIFT AND SCATTER OUT THE LOW LVLS CLOUDS...LEAVING MOSTLY HIGH AND MID LVL OVERCAST. ENOUGH PEEKS OF SUN AND INSOLATION WILL HELP TEMPS INTO THE LOW TO MID 60S. WEAK LOW PRES SPINNING OUT IN THE ATLANTIC WILL DRIFT NWD THRU THE DAY...AND MAY BACK SOME SHRA TOWARDS THE MIDCOAST. HAVE SOME LOW POP FOR THE AFTERNOON THERE...WHILE GRADUALLY INCREASING POP FROM THE W AS COLD FNT APPROACHES LATE IN THE DAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... EXPECT THAT MOST OF THE SHRA HOLD OFF UNTIL AFTER 00Z IN THE W...AND THIS IS SUPPORTED BY THE LATEST RUNS OF THE HRRR AND SPC WRF. LOW PRES IS NOT REALLY DEEPENING...AS PARENT S/WV IS SHEARING OUT AND LIFTING QUICKLY NEWD WITH TIME. AS SUCH...NOT SEEING MUCH MECHANISM OUT THERE FOR WIDESPREAD RNFL. TRENDING POP DOWNWARDS EXCEPT IN THE MTNS...WHERE OROGRAPHIC LIFTING AND PROXIMITY TO FORCING WILL SUPPORT GREATER COVERAGE OF SHRA. WITH CLOUDS AND PCPN AROUND THE AREA...LOW TEMPS WILL BE QUITE MILD FOR THIS TIME OF YEAR. FNT QUICKLY CROSSING THE AREA EARLY THU...AS S/WV TROF AXIS PASSES E. S/WV RIDGING FOLLOWS IN ITS WAKE...SO DOWNSLOPING AND DRYING ALOFT SHOULD CLEAR OUT SHRA AND HELP TO BREAK UP CLOUDS LATE IN THE DAY. TEMPS SHOULD CLIMB WELL INTO THE 60S DURING THE DAY...WITH SRN NH AND SWRN ME MAKING A RUN INTO THE 70S WITH ENOUGH SUN. TRAILING S/WV LIFTING OUT OF THE OH RIVER VALLEY MAY SPREAD CLOUDS BACK INTO SWRN ZONES LATE IN THE DAY THU. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... A MORE ACTIVE PATTERN WILL DEVELOP OVER THE REGION AS WE END OUT THE WORK WEEK. AN AREA OF LOW PRESSURE WILL RAPIDLY CROSS THE AREA THURSDAY NIGHT INTO EARLY FRIDAY MORNING. THIS WILL BRING MORE PERSISTENT SHOWERS TO THE REGION MAINLY THURSDAY NIGHT...HOWEVER THE PRECIPITATION MAY LINGER FOR A COUPLE HOURS FRIDAY MORNING. MODELS HAVE COME INTO BETTER ALIGNMENT WITH THE TIMING OF THIS SYSTEM. A WEAK RIDGE OF HIGH PRESSURE WILL BRING DRIER AIR TO THE REGION FRIDAY AFTERNOON AND FRIDAY NIGHT. OVER THE WEEKEND...CYCLONIC FLOW ALOFT WILL ALLOW FOR SCATTERED SHOWER ACTIVITY...FOLLOWED BY A REINFORCING COLD FRONT SUNDAY NIGHT. HIGH PRESSURE WILL BUILD FOR MONDAY...BUT TEMPS WILL REMAIN NEAR OR BELOW NORMAL FOR THIS TIME OF THE YEAR AS A WARM FRONT APPROACHES FROM THE WEST NEXT TUESDAY. && .AVIATION /14Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM...AREAS OF IFR OR LOWER THIS MORNING IN COASTAL STRATUS. CONDITIONS WILL IMPROVE TO VFR TODAY...BEFORE MVFR CIGS MOVE IN FROM THE W AS COLD FNT APPROACHES THE REGION. SCT SHRA MAY MOVE INTO THE CT RIVER VALLEY AFTER 00Z. LONG TERM...VFR CONDITIONS WITH AREAS OF MVFR IN SCATTERED SHOWERS FRIDAY AFTERNOON THROUGH SUNDAY NIGHT. MORE PERSISTENT SHOWERS ARE LIKELY THURSDAY NIGHT INTO EARLY FRIDAY MORNING WITH IFR CONDITIONS AT TIMES. && .MARINE... SHORT TERM...WINDS AND SEAS EXPECTED TO REMAIN BELOW SCA THRESHOLDS. LONG TERM...WINDS AND WAVES SHOULD REMAIN BELOW SMALL CRAFT CRITERIA WITH SEVERAL DISTURBANCES CROSSING THE WATERS. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...NONE. && $$ UPDATE...HANES
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
725 AM EDT WED OCT 16 2013 .SYNOPSIS... A STALLED FRONT TO OUR SOUTH WILL GRADUALLY RETURN NORTH AS A WARM FRONT LATE TONIGHT AND WEDNESDAY. A COLD FRONT WILL APPROACH FROM THE GREAT LAKES WEDNESDAY NIGHT THEN CROSS THE AREA ON THURSDAY. WEAK LOW PRESSURE CROSSES THE AREA FRIDAY AND AGAIN ON SUNDAY BRINGING WIDESPREAD SHOWERS TO THE REGION. A WARM FRONT APPROACHES ON MONDAY WHILE HIGH PRESSURE TRIES TO BUILD IN FROM THE SOUTH. && .NEAR TERM /THROUGH TONIGHT/... UPDATE...MINOR CHANGES TO ACCOUNT FOR CURRENT OBSERVATIONAL TRENDS. PREVIOUS DISCUSSION...WARM FNT LIFTING INTO THE REGION WILL BRING A DREARY START TO THE DAY. WEAK ONSHORE FLOW AND NEARLY SATURATED LOW LVLS WILL BRING STRATUS INTO COASTAL AREAS EARLY. WEAK WAA ALOFT WILL PROVIDE ENOUGH LIFT FOR SOME DZ IN THESE AREAS THRU SUNRISE. DAYTIME HEATING WILL EVENTUALLY HELP LIFT AND SCATTER OUT THE LOW LVLS CLOUDS...LEAVING MOSTLY HIGH AND MID LVL OVERCAST. ENOUGH PEEKS OF SUN AND INSOLATION WILL HELP TEMPS INTO THE LOW TO MID 60S. WEAK LOW PRES SPINNING OUT IN THE ATLANTIC WILL DRIFT NWD THRU THE DAY...AND MAY BACK SOME SHRA TOWARDS THE MIDCOAST. HAVE SOME LOW POP FOR THE AFTERNOON THERE...WHILE GRADUALLY INCREASING POP FROM THE W AS COLD FNT APPROACHES LATE IN THE DAY. && .SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/... EXPECT THAT MOST OF THE SHRA HOLD OFF UNTIL AFTER 00Z IN THE W...AND THIS IS SUPPORTED BY THE LATEST RUNS OF THE HRRR AND SPC WRF. LOW PRES IS NOT REALLY DEEPENING...AS PARENT S/WV IS SHEARING OUT AND LIFTING QUICKLY NEWD WITH TIME. AS SUCH...NOT SEEING MUCH MECHANISM OUT THERE FOR WIDESPREAD RNFL. TRENDING POP DOWNWARDS EXCEPT IN THE MTNS...WHERE OROGRAPHIC LIFTING AND PROXIMITY TO FORCING WILL SUPPORT GREATER COVERAGE OF SHRA. WITH CLOUDS AND PCPN AROUND THE AREA...LOW TEMPS WILL BE QUITE MILD FOR THIS TIME OF YEAR. FNT QUICKLY CROSSING THE AREA EARLY THU...AS S/WV TROF AXIS PASSES E. S/WV RIDGING FOLLOWS IN ITS WAKE...SO DOWNSLOPING AND DRYING ALOFT SHOULD CLEAR OUT SHRA AND HELP TO BREAK UP CLOUDS LATE IN THE DAY. TEMPS SHOULD CLIMB WELL INTO THE 60S DURING THE DAY...WITH SRN NH AND SWRN ME MAKING A RUN INTO THE 70S WITH ENOUGH SUN. TRAILING S/WV LIFTING OUT OF THE OH RIVER VALLEY MAY SPREAD CLOUDS BACK INTO SWRN ZONES LATE IN THE DAY THU. && .LONG TERM /FRIDAY THROUGH TUESDAY/... A MORE ACTIVE PATTERN WILL DEVELOP OVER THE REGION AS WE END OUT THE WORK WEEK. AN AREA OF LOW PRESSURE WILL RAPIDLY CROSS THE AREA THURSDAY NIGHT INTO EARLY FRIDAY MORNING. THIS WILL BRING MORE PERSISTENT SHOWERS TO THE REGION MAINLY THURSDAY NIGHT...HOWEVER THE PRECIPITATION MAY LINGER FOR A COUPLE HOURS FRIDAY MORNING. MODELS HAVE COME INTO BETTER ALIGNMENT WITH THE TIMING OF THIS SYSTEM. A WEAK RIDGE OF HIGH PRESSURE WILL BRING DRIER AIR TO THE REGION FRIDAY AFTERNOON AND FRIDAY NIGHT. OVER THE WEEKEND...CYCLONIC FLOW ALOFT WILL ALLOW FOR SCATTERED SHOWER ACTIVITY...FOLLOWED BY A REINFORCING COLD FRONT SUNDAY NIGHT. HIGH PRESSURE WILL BUILD FOR MONDAY...BUT TEMPS WILL REMAIN NEAR OR BELOW NORMAL FOR THIS TIME OF THE YEAR AS A WARM FRONT APPROACHES FROM THE WEST NEXT TUESDAY. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM...AREAS OF IFR OR LOWER THIS MORNING IN COASTAL STRATUS. CONDITIONS WILL IMPROVE TO VFR TODAY...BEFORE MVFR CIGS MOVE IN FROM THE W AS COLD FNT APPROACHES THE REGION. SCT SHRA MAY MOVE INTO THE CT RIVER VALLEY AFTER 00Z. LONG TERM...VFR CONDITIONS WITH AREAS OF MVFR IN SCATTERED SHOWERS FRIDAY AFTERNOON THROUGH SUNDAY NIGHT. MORE PERSISTENT SHOWERS ARE LIKELY THURSDAY NIGHT INTO EARLY FRIDAY MORNING WITH IFR CONDITIONS AT TIMES. && .MARINE... SHORT TERM...WINDS AND SEAS EXPECTED TO REMAIN BELOW SCA THRESHOLDS. LONG TERM...WINDS AND WAVES SHOULD REMAIN BELOW SMALL CRAFT CRITERIA WITH SEVERAL DISTURBANCES CROSSING THE WATERS. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...NONE. && $$ LEGRO/JC
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
529 AM EDT WED OCT 16 2013 .SYNOPSIS... A STALLED FRONT TO OUR SOUTH WILL GRADUALLY RETURN NORTH AS A WARM FRONT LATE TONIGHT AND WEDNESDAY. A COLD FRONT WILL APPROACH FROM THE GREAT LAKES WEDNESDAY NIGHT THEN CROSS THE AREA ON THURSDAY. WEAK LOW PRESSURE CROSSES THE AREA FRIDAY AND AGAIN ON SUNDAY BRINGING WIDESPREAD SHOWERS TO THE REGION. A WARM FRONT APPROACHES ON MONDAY WHILE HIGH PRESSURE TRIES TO BUILD IN FROM THE SOUTH. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATE...MINOR CHANGES TO ACCOUNT FOR CURRENT OBSERVATIONAL TRENDS. PREVIOUS DISCUSSION...WARM FNT LIFTING INTO THE REGION WILL BRING A DREARY START TO THE DAY. WEAK ONSHORE FLOW AND NEARLY SATURATED LOW LVLS WILL BRING STRATUS INTO COASTAL AREAS EARLY. WEAK WAA ALOFT WILL PROVIDE ENOUGH LIFT FOR SOME DZ IN THESE AREAS THRU SUNRISE. DAYTIME HEATING WILL EVENTUALLY HELP LIFT AND SCATTER OUT THE LOW LVLS CLOUDS...LEAVING MOSTLY HIGH AND MID LVL OVERCAST. ENOUGH PEEKS OF SUN AND INSOLATION WILL HELP TEMPS INTO THE LOW TO MID 60S. WEAK LOW PRES SPINNING OUT IN THE ATLANTIC WILL DRIFT NWD THRU THE DAY...AND MAY BACK SOME SHRA TOWARDS THE MIDCOAST. HAVE SOME LOW POP FOR THE AFTERNOON THERE...WHILE GRADUALLY INCREASING POP FROM THE W AS COLD FNT APPROACHES LATE IN THE DAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... EXPECT THAT MOST OF THE SHRA HOLD OFF UNTIL AFTER 00Z IN THE W...AND THIS IS SUPPORTED BY THE LATEST RUNS OF THE HRRR AND SPC WRF. LOW PRES IS NOT REALLY DEEPENING...AS PARENT S/WV IS SHEARING OUT AND LIFTING QUICKLY NEWD WITH TIME. AS SUCH...NOT SEEING MUCH MECHANISM OUT THERE FOR WIDESPREAD RNFL. TRENDING POP DOWNWARDS EXCEPT IN THE MTNS...WHERE OROGRAPHIC LIFTING AND PROXIMITY TO FORCING WILL SUPPORT GREATER COVERAGE OF SHRA. WITH CLOUDS AND PCPN AROUND THE AREA...LOW TEMPS WILL BE QUITE MILD FOR THIS TIME OF YEAR. FNT QUICKLY CROSSING THE AREA EARLY THU...AS S/WV TROF AXIS PASSES E. S/WV RIDGING FOLLOWS IN ITS WAKE...SO DOWNSLOPING AND DRYING ALOFT SHOULD CLEAR OUT SHRA AND HELP TO BREAK UP CLOUDS LATE IN THE DAY. TEMPS SHOULD CLIMB WELL INTO THE 60S DURING THE DAY...WITH SRN NH AND SWRN ME MAKING A RUN INTO THE 70S WITH ENOUGH SUN. TRAILING S/WV LIFTING OUT OF THE OH RIVER VALLEY MAY SPREAD CLOUDS BACK INTO SWRN ZONES LATE IN THE DAY THU. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... A MORE ACTIVE PATTERN WILL DEVELOP OVER THE REGION AS WE END OUT THE WORK WEEK. AN AREA OF LOW PRESSURE WILL RAPIDLY CROSS THE AREA THURSDAY NIGHT INTO EARLY FRIDAY MORNING. THIS WILL BRING MORE PERSISTENT SHOWERS TO THE REGION MAINLY THURSDAY NIGHT...HOWEVER THE PRECIPITATION MAY LINGER FOR A COUPLE HOURS FRIDAY MORNING. MODELS HAVE COME INTO BETTER ALIGNMENT WITH THE TIMING OF THIS SYSTEM. A WEAK RIDGE OF HIGH PRESSURE WILL BRING DRIER AIR TO THE REGION FRIDAY AFTERNOON AND FRIDAY NIGHT. OVER THE WEEKEND...CYCLONIC FLOW ALOFT WILL ALLOW FOR SCATTERED SHOWER ACTIVITY...FOLLOWED BY A REINFORCING COLD FRONT SUNDAY NIGHT. HIGH PRESSURE WILL BUILD FOR MONDAY...BUT TEMPS WILL REMAIN NEAR OR BELOW NORMAL FOR THIS TIME OF THE YEAR AS A WARM FRONT APPROACHES FROM THE WEST NEXT TUESDAY. && .AVIATION /10Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM...AREAS OF IFR OR LOWER THIS MORNING IN COASTAL STRATUS. CONDITIONS WILL IMPROVE TO VFR TODAY...BEFORE MVFR CIGS MOVE IN FROM THE W AS COLD FNT APPROACHES THE REGION. SCT SHRA MAY MOVE INTO THE CT RIVER VALLEY AFTER 00Z. LONG TERM...VFR CONDITIONS WITH AREAS OF MVFR IN SCATTERED SHOWERS FRIDAY AFTERNOON THROUGH SUNDAY NIGHT. MORE PERSISTENT SHOWERS ARE LIKELY THURSDAY NIGHT INTO EARLY FRIDAY MORNING WITH IFR CONDITIONS AT TIMES. && .MARINE... SHORT TERM...WINDS AND SEAS EXPECTED TO REMAIN BELOW SCA THRESHOLDS. LONG TERM...WINDS AND WAVES SHOULD REMAIN BELOW SMALL CRAFT CRITERIA WITH SEVERAL DISTURBANCES CROSSING THE WATERS. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...NONE. && $$ LEGRO/JC
AREA FORECAST DISCUSSION
NWS GRAY ME
237 AM EDT WED OCT 16 2013 .SYNOPSIS... A STALLED FRONT TO OUR SOUTH WILL GRADUALLY RETURN NORTH AS A WARM FRONT LATE TONIGHT AND WEDNESDAY. A COLD FRONT WILL APPROACH FROM THE GREAT LAKES WEDNESDAY NIGHT THEN CROSS THE AREA ON THURSDAY. WEAK LOW PRESSURE CROSSES THE AREA FRIDAY AND AGAIN ON SUNDAY BRINGING WIDESPREAD SHOWERS TO THE REGION. A WARM FRONT APPROACHES ON MONDAY WHILE HIGH PRESSURE TRIES TO BUILD IN FROM THE SOUTH. && .NEAR TERM /THROUGH TODAY/... WARM FNT LIFTING INTO THE REGION WILL BRING A DREARY START TO THE DAY. WEAK ONSHORE FLOW AND NEARLY SATURATED LOW LVLS WILL BRING STRATUS INTO COASTAL AREAS EARLY. WEAK WAA ALOFT WILL PROVIDE ENOUGH LIFT FOR SOME DZ IN THESE AREAS THRU SUNRISE. DAYTIME HEATING WILL EVENTUALLY HELP LIFT AND SCATTER OUT THE LOW LVLS CLOUDS...LEAVING MOSTLY HIGH AND MID LVL OVERCAST. ENOUGH PEEKS OF SUN AND INSOLATION WILL HELP TEMPS INTO THE LOW TO MID 60S. WEAK LOW PRES SPINNING OUT IN THE ATLANTIC WILL DRIFT NWD THRU THE DAY...AND MAY BACK SOME SHRA TOWARDS THE MIDCOAST. HAVE SOME LOW POP FOR THE AFTERNOON THERE...WHILE GRADUALLY INCREASING POP FROM THE W AS COLD FNT APPROACHES LATE IN THE DAY. && .SHORT TERM /TONIGHT THROUGH 6 PM THURSDAY/... EXPECT THAT MOST OF THE SHRA HOLD OFF UNTIL AFTER 00Z IN THE W...AND THIS IS SUPPORTED BY THE LATEST RUNS OF THE HRRR AND SPC WRF. LOW PRES IS NOT REALLY DEEPENING...AS PARENT S/WV IS SHEARING OUT AND LIFTING QUICKLY NEWD WITH TIME. AS SUCH...NOT SEEING MUCH MECHANISM OUT THERE FOR WIDESPREAD RNFL. TRENDING POP DOWNWARDS EXCEPT IN THE MTNS...WHERE OROGRAPHIC LIFTING AND PROXIMITY TO FORCING WILL SUPPORT GREATER COVERAGE OF SHRA. WITH CLOUDS AND PCPN AROUND THE AREA...LOW TEMPS WILL BE QUITE MILD FOR THIS TIME OF YEAR. FNT QUICKLY CROSSING THE AREA EARLY THU...AS S/WV TROF AXIS PASSES E. S/WV RIDGING FOLLOWS IN ITS WAKE...SO DOWNSLOPING AND DRYING ALOFT SHOULD CLEAR OUT SHRA AND HELP TO BREAK UP CLOUDS LATE IN THE DAY. TEMPS SHOULD CLIMB WELL INTO THE 60S DURING THE DAY...WITH SRN NH AND SWRN ME MAKING A RUN INTO THE 70S WITH ENOUGH SUN. TRAILING S/WV LIFTING OUT OF THE OH RIVER VALLEY MAY SPREAD CLOUDS BACK INTO SWRN ZONES LATE IN THE DAY THU. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... A MORE ACTIVE PATTERN WILL DEVELOP OVER THE REGION AS WE END OUT THE WORK WEEK. AN AREA OF LOW PRESSURE WILL RAPIDLY CROSS THE AREA THURSDAY NIGHT INTO EARLY FRIDAY MORNING. THIS WILL BRING MORE PERSISTENT SHOWERS TO THE REGION MAINLY THURSDAY NIGHT...HOWEVER THE PRECIPITATION MAY LINGER FOR A COUPLE HOURS FRIDAY MORNING. MODELS HAVE COME INTO BETTER ALIGNMENT WITH THE TIMING OF THIS SYSTEM. A WEAK RIDGE OF HIGH PRESSURE WILL BRING DRIER AIR TO THE REGION FRIDAY AFTERNOON AND FRIDAY NIGHT. OVER THE WEEKEND...CYCLONIC FLOW ALOFT WILL ALLOW FOR SCATTERED SHOWER ACTIVITY...FOLLOWED BY A REINFORCING COLD FRONT SUNDAY NIGHT. HIGH PRESSURE WILL BUILD FOR MONDAY...BUT TEMPS WILL REMAIN NEAR OR BELOW NORMAL FOR THIS TIME OF THE YEAR AS A WARM FRONT APPROACHES FROM THE WEST NEXT TUESDAY. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM...AREAS OF IFR OR LOWER THIS MORNING IN COASTAL STRATUS. CONDITIONS WILL IMPROVE TO VFR TODAY...BEFORE MVFR CIGS MOVE IN FROM THE W AS COLD FNT APPROACHES THE REGION. SCT SHRA MAY MOVE INTO THE CT RIVER VALLEY AFTER 00Z. LONG TERM...VFR CONDITIONS WITH AREAS OF MVFR IN SCATTERED SHOWERS FRIDAY AFTERNOON THROUGH SUNDAY NIGHT. MORE PERSISTENT SHOWERS ARE LIKELY THURSDAY NIGHT INTO EARLY FRIDAY MORNING WITH IFR CONDITIONS AT TIMES. && .MARINE... SHORT TERM...WINDS AND SEAS EXPECTED TO REMAIN BELOW SCA THRESHOLDS. LONG TERM...WINDS AND WAVES SHOULD REMAIN BELOW SMALL CRAFT CRITERIA WITH SEVERAL DISTURBANCES CROSSING THE WATERS. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...NONE. && $$
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1203 AM EDT WED OCT 16 2013 .SYNOPSIS... ISSUED AT 414 PM EDT TUE OCT 15 2013 LOW PRESSURE NEAR THE TWIN CITIES TUESDAY AFTERNOON...WILL MOVE TO EASTERN LAKE SUPERIOR BY WEDNESDAY MORNING. THIS SYSTEM WILL PRODUCE SHOWERS TONIGHT ACROSS ALL OF NORTHERN MICHIGAN. NEAR NORMAL TEMPERATURES WILL LINGER BEHIND THIS SYSTEM FOR THE REST OF THE WORK WEEK. MUCH COOLER WEATHER APPEARS LIKELY BY THE END OF THE WEEKEND. && .UPDATE... ISSUED AT 1016 PM EDT TUE OCT 15 2013 TWEAKED POPS AND REMOVED THUNDER FROM THE FORECAST BASED ON CURRENT RADAR TRENDS. BEGINNING TO SEE SOME CONVECTIVE SHOWER ACTIVITY DEVELOP OVER THE SOUTHERN HALF OF LAKE MICHIGAN...NOT CONFIDENT THAT THIS WILL EVOLVE INTO ANY THUNDER THREAT GIVEN 250J/KG OF ELEVATED CAPE PER LATEST SPC MESOANALYSIS. NUMEROUS SHOWERS...WITH PATCHY DRIZZLE OVER THE HIGHER TERRAIN...WILL CONTINUE ACROSS THE CWA FOR THE REMAINDER OF THE EVENING INTO THE OVERNIGHT WITH THE DEEPEST MOISTURE NOW EXITING NE LOWER PER LATEST WATER VAPOR LOOP. SKIES WILL REMAIN OVERALL CLOUDY...BUT WOULD NOT BE SURPRISED TO SEE SOME CLEARING ASSOCIATED WITH APPROACHING DRY SLOT CLIP THE SW PORTION OF THE FORECAST AREA FOR A BRIEF TIME...BEFORE WRAP AROUND CLOUDS AND MOISTURE FILTER BACK INTO THE PICTURE LATE TONIGHT. TEMPERATURES WILL REMAIN STEADY OR SLOWLY RISE LATE THIS EVENING AS OCCLUDED FRONT APPROACHES...BUT WILL DROP BACK INTO THE 40S LATE TONIGHT AS COLD AIR ADVECTION ENSUES. UPDATE ISSUED AT 743 PM EDT TUE OCT 15 2013 LITTLE CHANGES TO THE FORECAST AT THIS TIME. SWATH OF RAINFALL ASSOCIATED WITH WAA/ISENTROPIC ASCENT IS RAPIDLY MOVING THROUGH THE CWA ATTM...AND WILL LIKELY BE OUT OF THE AREA BY AROUND 03Z. MAIN QUESTION IS WHETHER OR NOT WE CAN REDEVELOP SOME CONVECTION WITH APPROACHING DRY SLOT AND COLD FRONT. THINGS NOT LOOKING GOOD AT ALL REGARDING THAT SCENARIO...WITH NO SIGNS OF CONVECTION UPSTREAM. WHILE LATEST RUC CONTINUES TO SHOW SOME ELEVATED INSTABILITY SKIRTING MAINLY THE NORTHERN HALF OF THE CWA...SHORT TERM RUC SOUNDINGS ALSO DEPICT SOME MID LEVEL CAPPING WITH THE ARRIVAL OF SAID DRY SLOT/STEEPER MID LEVEL LAPSE RATES. WILL MAINTAIN THUNDER MENTION FOR NOW...BUT WILL LIKELY HAVE TO REMOVE IT FROM THE FORECAST BY THE NEXT UPDATE IF THINGS DON`T GET GOING SOON. OTHERWISE LINGERING MOIST BOUNDARY LAYER WILL BRING PERIODS OF LOW CLOUDS AND VERY LIGHT RAIN SHOWERS OR DRIZZLE FOR THE REMAINDER OF THE EVENING INTO THE EARLY OVERNIGHT. TEMPERATURES WILL REMAIN STEADY IN THE 50S...WITH WINDS VEERING TO THE SOUTHWEST LATER TONIGHT WITH THE FRONTAL PASSAGE AND SUBTLE INCREASE IN THE PRESSURE GRADIENT. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 414 PM EDT TUE OCT 15 2013 A BIT OF A CHALLENGING FORECAST THE NEXT 24 HOURS...BUT IN THE GRAND SCHEME OF THINGS...QUITE TYPICAL FOR OCTOBER...WITH THE MAIN FORECAST ISSUES BEING RAIN AND POSSIBLE CONVECTION THROUGH THE EVENING...AND LAKE EFFECT/WATERSPOUT ISSUES INTO WEDNESDAY. EARLY AFTERNOON ANALYSIS PLACES A RATHER POTENT CLOSED LOW MEANDERING THROUGH SOUTHERN MINNESOTA...TAKING ON THE CLASSIC OCCLUDING CYCLONE LOOK THE PAST 12 HOURS. A DISTINCT DRY SLOT IS JUST NOW PUNCHING THROUGH THE WESTERN LAKES...WITH A NARROW RIBBON OF DEEP MOISTURE (PWAT VALUES IN EXCESS OF 1.1 INCHES) NOTED FLOWING FROM THE BAJA PENINSULA RIGHT UP INTO OUR NECK OF THE WOODS. REGIONAL RADAR MOSAIC SHOWS A NICE BATCH OF RAIN FINALLY WORKING EAST FROM WISCONSIN INTO LAKE MICHIGAN AND BUMPING UP AGAINST THE NORTHWEST CWA...WITH A BIT MORE NARROWED RAIN SHIELD EXTENDING INTO THE LOWER LAKES AND TO A GREATER EXTENT THE WESTERN TENNESSEE/MID MISSISSIPPI VALLEY. THAT NORTHERN RAIN SHIELD IS ASSOCIATED WITH A DECENT AXIS OF BOTH LOW/MID LEVEL WARM ADVECTION ASCENT AND PRONOUNCED 850-500MB QG UPWARD FORCING...WHILE THE SOUTHERN STUFF IS MORE TIED TO AN UPPER JET STREAK/JET FORCING RIDING THROUGH THE SOUTHERN PLAINS. THE BIG QUESTION FOR LATE AFTERNOON/EVENING IS JUST WHAT TYPE OF RAIN COVERAGE/AMOUNTS WE WILL END UP WITH. NO DOUBT THE CURRENT RAIN SHIELD WILL CONTINUE ITS SLOW NORTH/NORTHEAST JAUNT...SUGGESTING GOING CATEGORICAL POPS ARE JUST FINE FOR MUCH OF NORTHWEST LOWER AND EASTERN UPPER. THE BIG QUESTION IS WHAT HAPPENS ACROSS NORTHEAST LOWER AS THAT BAND MAY FIZZLE WITH TIME AS IT OUTRUNS THE BETTER ASCENT WHILE A NOTABLE BREAK HAS ALREADY DEVELOPED ACROSS THE SOUTHERN LAKES. A BIT CONCERNED THIS BREAK MAY SLIDE NORTHEASTWARD ON THE DOWNWARD SIDE OF THE UPPER JET AND PROVIDE LESSER AMOUNTS WITH EASTWARD EXTENT. HOWEVER...WITH THAT SAID...STILL BELIEVE JUST ABOUT ALL FOLKS WILL END UP WITH SOME MEASURABLE RAINS AND CATEGORICAL POPS WILL CONTINUE. AS FOR CONVECTIVE CHANCES...CONFIDENCE IS WANING GIVEN THE LACK OF ANY UPSTREAM ACTIVITY JUST YET. STILL LOOKING AT A QUITE STEEP PLUME OF 700-500MB LAPSE RATES (PUSHING 8C/KM) WORKING ACROSS IOWA/ SOUTHERN WISCONSIN...WHERE THERE IS SOME CLEARING ONGOING AND HINTS OF CU DEVELOPMENT. WILL HAVE TO WATCH AND SEE IF THINGS CAN GET GOING IN ANOTHER FEW HOURS...BUT WILL OVERALL LOWER THE THUNDER MENTION TO SLIGHT CHANCE AS THE ELEVATED INSTABILITY (UP TO 500J/KG) AND STEEP LAPSE RATES WILL BE THERE ALONG THE DRY SLOT...BUT CONFIDENCE IS LOW WITH THE LACK OF CURRENT ACTIVITY. OTHERWISE...DRY SLOT WILL END THE MORE WIDESPREAD RAINFALL TOWARD OR JUST AFTER MIDNIGHT...WITH MORE SHOWERY CONDITIONS POSSIBLE THE REST OF THE NIGHT...PERHAPS ENHANCED BY THE LAKES TOWARD MORNING AS H8 TEMPS COOL BACK TOWARD 3C. OUR BETTER CHANCE FOR LAKE ENHANCED PRECIP WILL COME WEDNESDAY AS THE UPPER LOW TO THE WEST OPENS UP AND SLOWLY SLIDES OVERHEAD. NICE SLUG OF DEEPER MOISTURE AND MORE THAN SUFFICIENT LAKE INSTABILITY SHOULD RESULT IN QUITE A FEW LAKE EFFECT/ENHANCED SHOWERS...WITH SOME DIURNAL COMPONENT ALSO POSSIBLE BENEATH THE UPPER COLD POOL. SHOULD SEE A WATERSPOUT THREAT FOR A TIME...ESPECIALLY WEDNESDAY MORNING AS THE DEEPER VORTICITY AXIS PULLS OVERHEAD...WHILE A SECONDARY COLD FRONT/FORCING BOUNDARY CROSSES LAKE MICHIGAN. LATEST SZILAGYI NOMOGRAM PLOTS HIGHLIGHT THIS IDEA WELL AND PROBABLY WORTH A MENTION. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 414 PM EDT TUE OCT 15 2013 OVERVIEW: FOUR-WAVE LONG WAVE PATTERN IN PLACE ACROSS THE NRN HEMISPHERE WITH LONG WAVE TROUGHINESS DEEPENING ACROSS CENTRAL NOAM IN RESPONSE TO LONG-WAVE RIDGING BUILDING FROM THE GULF OF ALASKA DOWN ALONG THE PACIFIC COAST. THIS AMPLIFIED RIDGE WEST/TROUGH EAST PATTERN STILL ON TRACK TO GET "LOCKED IN" THROUGH AT LEAST THE NEXT SEVEN TO TEN DAYS (AND BEYOND) LEADING TO THE MUCH ADVERTISED COOL DOWN AND SLIDE INTO TRUE FALL FOR THE MIDWEST/GREAT LAKES...AND A SIZABLE PART OF EASTERN NOAM FOR THAT MATTER. IN FACT...A SUBSTANTIAL COOL DOWN MAY BE IN THE WORKS AS A COUPLE POCKETS OF FAIRLY COLD AIR GET DISLODGED FROM NRN CANADA AND SLIDE DOWN INTO THE MIDWEST/GREAT LAKES REGION GOING THROUGH THE WEEKEND AND NEXT WEEK (POSSIBLY LINKED TO ONGOING TYPHOON ACTIVITY IN THE WESTERN PACIFIC). REGARDLESS...AT LEAST A POSSIBILITY THAT WE SEE A LITTLE SNOW OR AT LEAST SOME SNOW OR RAIN/SNOW MIX IN THIS CWA DURING THE COURSE OF THE EXTENDED FORECAST. IN THE SHORTER TERM...NO SNOW THROUGH THE BALANCE OF THE WORK WEEK AS WE ARE JUST NOT COLD ENOUGH...YET. BUT WE DO HAVE A COUPLE SRN STREAM WAVES TO WORRY ABOUT AS THEY ROTATE AROUND THE AFOREMENTIONED DEEPENING LONG WAVE TROUGH. FIRST OF THESE WAVES IS MOVING THROUGH THE REGION TONIGHT AND WEDNESDAY (HANDLED IN THE SHORT TERM PART OF THE FORECAST). NEXT PIECE OF SRN STREAM ENERGY/SHORT WAVE DIPPING INTO THE FOUR CORNERS REGION TODAY AND FORECAST TO SWING UP THROUGH THE MIDWEST WEDNESDAY NIGHT...THEN UP THROUGH LOWER MICHIGAN DURING THE DAY THURSDAY. NOT A PARTICULARLY MOIST SYSTEM ORIGINATING FROM THE FOUR CORNERS AND NO SUPPORTING TAP OF GULF MOISTURE. BUT IT IS A DECENT WAVE LEADING TO A NICE SHOT OF QG-UPWARD FORCING MOVING THROUGH LOWER MICHIGAN THURSDAY AFTERNOON. BEST CHANCE FOR RAINFALL LOOKING TO OCCUR ACROSS CENTRAL AND SRN LOWER MICHIGAN ALONG AND SOUTH OF THE SHORT WAVE TRACK. BUT NOT COMFORTABLE HAVING A COMPLETELY DRY FORECAST FOR THIS CWA ON THURSDAY AND HAVE INTRODUCED SOME CHANCY POPS FOR THE S/SE HALF OF THE CWA PARTICULARLY DOWN TOWARD SAGINAW BAY. THURSDAY NIGHT THROUGH FRIDAY...BEHIND THURSDAYS SYSTEM...A BRIEF LULL ANTICIPATED THURSDAY NIGHT COURTESY OF A WEDGE OF DRIER AIR/SUBTLE SHORT WAVE RIDGING AND DOWNWARD QG FORCING. THAT SAID...CERTAINLY ENOUGH LOW LEVEL COLD AIR TO WORRY ABOUT LAKE EFFECT RAIN SHOWER PROSPECTS GIVEN H8 TEMPS JUST A FEW DEGREES ABOVE 0C. BUT IN TRYING TO FIND A LEAST ONE DRY FORECAST PERIOD OVER THE NEXT SEVERAL...THURSDAY NIGHT PROBABLY HAS THE BEST SHOT AND WILL LEAVE IT DRY FOR NOW. HEADING THROUGH FRIDAY...UPPER LEVEL TROUGHINESS BEGINS TO DESCEND INTO THE UPPER MIDWEST/WESTERN GREAT LAKES BEGINNING WITH A SUBTLE COLD FRONT PASSAGE DURING THE DAY FRIDAY. POSSIBILITIES FOR ANOTHER BATCH OF RAINFALL TO DEVELOP ALONG THE FRONT...ADVANCING THROUGH THE REGION THROUGH THE DAY FRIDAY FOLLOWED BY CONTINUING LAKE INDUCED RAIN SHOWER POSSIBILITIES FRIDAY NIGHT. OVERALL...THE START OF A RATHER UNSETTLED AND COOLER PERIOD FOR THE GREAT LAKES. SATURDAY THROUGH TUESDAY (EXTENDED PERIODS)... AS MENTIONED ABOVE...SUBSTANTIAL TROUGHINESS/COLDER AIR CARVES OUT ACROSS CENTRAL AND EASTERN CANADA AND DOWN INTO THE UPPER MIDWEST AND GREAT LAKES DURING THE COURSE OF THE WEEKEND. POTENTIAL FOR ANOTHER REINFORCING PUSH OF YET COLDER AIR FOR THE FIRST HALF OF NEXT WORK WEEK. BUT THE DEVIL IS IN THE DETAILS AND THE GFS/EURO SOLUTIONS HAVE HAD SUBSTANTIAL DIFFERENCES ON JUST HOW THE PATTERN EVOLVES AND HOW COLD IT GETS. EURO HAS BEEN RELUCTANT TO DRAG THE MORE SUBSTANTIAL COLD AIR (COLD ENOUGH FOR THE MENTION OF SNOW) INTO THE GREAT LAKES UNTIL NEXT WEEK...WHILE GFS DEVELOPS A STRONGER LOW PRESSURE SYSTEM FOR SATURDAY INTO SUNDAY WHICH DRAGS -4C TO -6C H8 AIR INTO THE REGION AS EARLY AS SUNDAY (USUALLY NEED AT LEAST -5C H8 TEMPS THIS TIME OF YEAR TO SEE SNOW). THE OVERRIDING IDEA IN THE FORECAST WILL BE A STRETCH OF BELOW NORMAL TEMPERATURES AND UNSETTLED (WET) WEATHER THROUGH THE EXTENDED. BUT IT IS POSSIBLE WE SEE A LITTLE BIT OF SNOW OR RAIN/SNOW MIX FOR INLAND AREAS EITHER LATE SATURDAY INTO SUNDAY (PER GFS COLDER IDEA) OR THE EARLY TO MID PART OF THE NEXT WEEK AS SOME THE COLDEST AIR FINALLY GETS PULLED INTO THE REGION. HAVE NOT ADDED THE MENTION OF SNOW TO THE FORECAST JUST YET HOWEVER...GIVEN THE UNCERTAINTY AND GIVEN THAT...AT LEAST RIGHT NOW...WHATEVER SNOW WE MIGHT SEE LOOKS TRANSIENT AND FAIRLY LOW IMPACT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1154 PM EDT TUE OCT 15 2013 MARGINAL IFR CONDITIONS WILL CONTINUE FOR PLN AND APN...WITH MAINLY MVFR CIGS FOR TVC AND MBL FOR THE OVERNIGHT HOURS. PATCHES OF LIGHT RAIN OR DRIZZLE WILL ALSO BE IN THE REGION WITH LOW LEVEL MOISTURE IN PLACE. A SLUG OF LOWER LEVEL DRY AIR HAS MOVED UP THE SPINE OF LAKE MICHIGAN...AND MAY AFFECT MBL TONIGHT BY BRINGING PERIODS OF CLEARING/VFR CIGS...BEFORE MVFR OVERCAST OVER WISCONSIN BEGINS TO PUSH INTO THE AREA. GUSTY SOUTHWESTERLY WINDS WILL BEGIN TO RAMP UP FOR TVC/MBL LATE TONIGHT...AND FOR THE REMAINING TAF SITES WEDNESDAY MORNING...AS THE LOW PRESSURE SYSTEM DEPARTS AND THE PRESSURE GRADIENT BEGINS TO TIGHTEN. && .MARINE... ISSUED AT 414 PM EDT TUE OCT 15 2013 SOME GUSTY CONDITIONS ARE EXPECTED ON THE LAKES...INITIALLY OUT OF THE SOUTHEAST AHEAD OF AN APPROACHING COLD FRONT...THEN SWITCHING SOUTHWEST LATER TONIGHT...AND EVENTUALLY NORTHWEST ON WEDNESDAY AS ANOTHER COLD FRONT PASSES. CONDITIONS WILL LIKELY APPROACH SMALL CRAFT ADVISORY LEVELS AT VARIOUS INTERVALS...AND HAVE SIMPLY CONTINUED THE GOING ADVISORY THROUGH THE NIGHT FOR MOST OF THE WATERS...THOUGH ARGUABLY NOT ALL SPOTS WILL SEE CRITERIA ALL OF THE TIME. THIS SYSTEM WILL DEPART INTO THURSDAY...LEAVING A PERIOD OF MUCH LIGHTER WINDS...BEFORE SEVERAL MORE WEAKER LOW PRESSURE AREAS TRACK NEARBY RIGHT ON INTO THE WEEKEND. AT THIS POINT...THERE IS NO BIG INDICATION THAN ANY SIGNIFICANT PERIODS OF WIND OR WAVES WILL OCCUR TROUGH AT LEAST SUNDAY. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...SMALL CRAFT ADVISORY UNTIL 8 PM EDT WEDNESDAY FOR LHZ345-347>349. SMALL CRAFT ADVISORY UNTIL 11 AM EDT WEDNESDAY FOR LHZ346. LM...SMALL CRAFT ADVISORY UNTIL 8 PM EDT WEDNESDAY FOR LMZ323-342- 344>346. SMALL CRAFT ADVISORY UNTIL 11 AM EDT WEDNESDAY FOR LMZ341. LS...SMALL CRAFT ADVISORY UNTIL 2 AM EDT WEDNESDAY FOR LSZ321-322. && $$ UPDATE...NS SYNOPSIS...JZ SHORT TERM...LAWRENCE LONG TERM...ADAM AVIATION...NS MARINE...LAWRENCE
AREA FORECAST DISCUSSION
NWS GLASGOW MT
902 PM MDT THU OCT 17 2013 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH SATURDAY... UPDATE TO FORECAST TO ADJUST FOR CURRENT RADAR AND SHORT TERM MODEL TRENDS. CURRENT AREA OF LIGHT TO BRIEFLY MODERATE SHOWERS IS SCATTERED AROUND MUCH OF THE CWA AND MOVING SOUTHEASTWARD. LATEST SHORT TERM GUIDANCE FROM HRRR AND SREF HAS THIS PRECIPITATION DECREASING AND MOSTLY GONE BY MIDNIGHT...EXCEPT IN THE EXTREME SOUTHEAST PART OF THE CWA. THIS AGREES WITH Q-VECTOR FORCING DECLINING WITH THE PASSAGE OF THE MID-LEVEL SHORTWAVE AT THAT TIME. SO FAR PRECIPITATION HAS BEEN IN THE FORM OF RAIN...EXCEPT FOR A BIT OF GRAUPEL FROM THE STRONGEST CONVECTIVE COLUMNS. THE FREEZING LEVEL...HOWEVER... IS NOT FAR ABOVE THE SURFACE AND SOME SNOW MAY BE SEEN LATER TONIGHT IN AREAS STILL RECEIVING PPT. TEMPERATURES ARE IN THE MID TO UPPER 30S AROUND THE REGION AND ARE NOT EXPECTED TO FALL AS MUCH AS PREVIOUS NIGHTS AS EXTENSIVE MID LEVEL CLOUDINESS IS EXPECTED TO PERSIST. WINDS WILL PICK-UP A BIT FRIDAY AFTERNOON AS 850MB WINDS ARE FORECAST TO BE AROUND 25 KTS AROUND A SURFACE HIGH MOVING THROUGH WYOMING. SLIGHT WARM ADVECTION WITH THIS NORTHWESTERLY FLOW MAY TEMPER THE MIXING OF THESE WINDS A BIT. MARTIN PREVIOUS DISCUSSION... UPPER TROUGH THAT SIGNALED ITSELF WITH YESTERDAY/S RAINSHOWERS CONTINUES TO DIG AS IT MOVES TOWARD THE GREAT LAKES. THIS HAS PUT US UNDER NW FLOW ALOFT AND WILL ALLOW SMALL DISTURBANCES TO OCCASIONALLY MOVE THROUGH THE AREA. ONE IS MOVING THROUGH TODAY BRINGING LIGHT SCATTERED RAINSHOWERS FROM THE NW. AS TEMPERATURES COOL TONIGHT...SOME HIGHER ELEVATIONS COULD SEE A FEW SNOWFLAKES MIX IN. WITH THE UPPER FEATURES DIGGING THE TROUGH FRIDAY...CLOUDS WILL HANG OVER THE AREA WITH SNOW AND/OR RAIN SHOWERS TO OUR EAST. THE BIGGEST DISTURBANCE THEN APPROACHES THE AREA SATURDAY...WITH THE SURFACE LOW CENTER DROPPING INTO SOUTHERN SASK SATURDAY AFTERNOON. THIS WILL PUSH A WARM FRONT INTO THE DAKOTAS AND ALLOW WARMER AIR TO PUSH INTO NE MT. WITH 850 MB TEMPS REACHING 5 TO 10*C...SURFACE TEMPS SHOULD REACH THE 50S EAST TO MID 60S WEST. TFJ .LONG TERM...SATURDAY NIGHT THROUGH THURSDAY... THE EXTENDED PERIOD BEGINNING SATURDAY NIGHT WILL SEE A GENERAL PATTERN OF A LONG WAVE UPPER RIDGE IN THE WEST AND A LONG WAVE UPPER TROUGH TO THE EAST. NORTHEAST MONTANA WILL BE LOCATED UNDER A NORTHERLY FLOW ALOFT. THE STATIONARY BOUNDARY BETWEEN THE COOL AIR UNDER THE TROUGH AND THE WARM AIR UNDER THE RIDGE WILL STRADDLE NORTH DAKOTA OR EASTERN MONTANA THROUGHOUT THE PERIOD. AN EMBEDDED SHORTWAVE WILL RIDE DOWN THE BOUNDARY SATURDAY NIGHT AND SUNDAY...NUDGING THE COOLER AIR TO THE WEST INTO NEMONT. OVERRIDING MOISTURE WILL BRING SOME PRECIPITATION...MOSTLY AS LIGHT RAIN. HOWEVER THE RAIN COULD TRANSITION OVER TO SNOW BY MONDAY MORNING. AN ASSOCIATED SURFACE TROUGH WILL ALSO BRING IN GUSTY NORTHWEST WIND SATURDAY NIGHT INTO SUNDAY. BEYOND MONDAY...THE REMAINDER OF THE PERIOD APPEARS TO BECOME MILD AS THE RIDGE MOVES THE STATIONARY BOUNDARY FARTHER EAST. TEMPERATURES WILL APPROACH NORMAL VALUES...BUT DUE TO THE NORTHERLY FLOW...DO NOT EXPECT TEMPERATURES TO RISE ABOVE NORMAL. SCT PREVIOUS DISCUSSION... SYNOPTIC SET UP...THE AXIS OF A LARGE COLD ARCTIC TROUGH RUNS FROM THE GREAT LAKES THROUGH MANITOBA AND INTO NUNAVUT. TO THE WEST OF THIS...A LARGE RIDGE RUNS UP THE COAST OF THE CONUS THROUGH BRITISH COLUMBIA AND INTO THE NORTHWEST TERRITORIES. NORTHEAST MONTANA BEGINS WEDGED BETWEEN THESE TWO VERY LARGE AIR MASSES WITH NORTH TO NORTHWEST FLOW ALOFT. SATURDAY NIGHT THROUGH MONDAY...FLOW ALOFT WILL REMAIN NORTH TO NORTHWEST PROVIDING AN EXPRESS LANE FOR COLD AIR AND CREATING AN WEST TO EAST WARM TO COLD TEMPERATURE GRADIENT. SATURDAY NIGHT A SHORTWAVE WILL PASS THROUGH THE FLOW WITH ENOUGH LIFT TO GENERATE LIGHT RAIN SHOWERS ACROSS THE CWA. WITH THE BOUNDARY/GRADIENT WAFFLING BACK AND FORTH BEST CHANCES WILL BE TO THE EAST BUT SOME OF THE SHOWERS ARE BOUND TO HIT THE CWA THROUGH SUNDAY. SUNDAY NIGHT INTO MONDAY STILL SHOW HIGH CHANCE OF SOMETHING OVERRUNNING THE BOUNDARY BUT TIMING IS VERY POOR AND QPF IS CURRENTLY LESS THAN THE PRIOR TWO PERIODS. MONDAY NIGHT ONWARD...AT THIS POINT ENSEMBLES STILL HOLD TO ROUGHLY A NORTHWEST FLOW ALOFT BUT BEGIN TO EMBED POORLY TIMED WAVES LARGER THAN THE TYPICAL SHORTWAVE WHICH ARE OUT OF PHASE WITH EAST OTHER. 00Z EC ATTEMPTS TO BRING A STRONG COLD FRONT THROUGH WEDNESDAY NIGHT BUT THIS COULD EASILY MORPH AND CHANGE. EXPECT ANYTHING FROM A TEMPORARY RISE IN TEMPS FROM A WEAK CHINOOK EVENT AND RIDGE TO A COOL DOWN/ISOLATED SHOWER FROM ANY TROUGH. HAVE CONTINUED THE TREND OF SKEWED TOWARD CONS AND CLIMO PRODUCTS WITH POPS BEING FAIRLY DRY UNTIL BETTER TIMING ON WAVES IS AVAILABLE. GAH && .AVIATION... RADAR AND SATELLITE IMAGERY SHOW ANOTHER WAVE MOVING THROUGH THE AREA THROUGH TONIGHT...THAT WILL BRING INCREASING MID-TO-LOW CLOUDS AND ISOLATED TO SCATTERED LIGHT PRECIPITATION...INITIALLY IN THE FORM OF RAIN...POSSIBLY TRANSITIONING TO SNOW SHOWERS LATE TONIGHT BEFORE ENDING BY MORNING. INTERMITTENT MVFR CEILINGS ARE POSSIBLE AT TIMES. EXPECT NORTHWEST WIND IN THE 10-15KT RANGE. SCT/BLM && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
636 PM CDT THU OCT 17 2013 .AVIATION...00Z TAFS FOR KOMA...KLNK AND KOFK. MVFR CONDITIONS PREVAIL EARLY IN THE TAF PERIOD...AND BIG QUESTION IS WHETHER THESE LOWER CLOUDS WILL SCATTER OUT AS SURFACE HIGH PRESSURE CONTINUES TO BUILD IN FROM THE WEST. OVERALL LOW CONFIDENCE ON TIMING...BUT HAVE FORECAST 05Z...AND WILL ADJUST AS NECESSARY IF CLOUDS DON`T SHOW ANY SIGNS OF BREAKING. && .PREV DISCUSSION... /ISSUED 322 PM CDT THU OCT 17 2013/ SHORT TERM...TONIGHT THROUGH SUNDAY. NORTHWESTERLY FLOW WITH A SERIES OF EMBEDDED WAVES WILL PREVAIL OVER FORECAST AREA THROUGH THE WEEKEND WITH SOME WARMING EXPECTED. FOR TONIGHT...FIRST IN SEVERAL WAVES WILL BE TRACKING FM DAKOTAS INTO MINNESOTA SPREADING CLOUDS ACROSS AREA INTO EARLY TONIGHT BEFORE PROBABLY DECREASING AFT 06Z. 18Z RAP AND 12Z 4KM WRF AND SOME HOP WRF MEMBERS SUGGESTED SOME VERY LIGHT PRECIP COULD CLIP NERN ZONES EARLY. ANOTHER WAVE MOVING TOWARD KS BY MORNING COULD SPREAD SOME MID/HIGH CLOUDS TOWARD SRN AND ESPECIALLY SWRN ZONES BY MORNING. THE VARIABLE CLOUDS...SOME WIND AND INITIALLY MODEST DWPTS WL LEAD TO KEEPING MOST LOWS A BIT ABOVE GUIDANCE. LITTLE CHANGE TO FRIDAY...KEPT IN SMALL POPS EXTREME SOUTH DUE TO SRN WAVE...ALTHOUGH APPEARS BULK OF ANY PRECIP COULD REMAIN TO OUR SOUTH. ALSO SHARP MID LVL TROUGH AXIS MOVING INTO ERN NEBRASKA TOWARD 00Z COULD ALLOW SOME SHOWER DEVELOPMENT AS H5 TEMPS IN MINUS UPPER 20S C MOVE OVER AREA. SPREAD SMALL CHANCES A BIT FARTHER S. SOMEWHAT DISCOUNTED NAM IN DOWNSLOPE MOISTURE LACKING FLOW BUT THIS COULD FACILITATE FUTURE CHANGES. DID TRIM TEMPS BACK A FEW DEGREES DUE TO EXPECTED CLOUDS...BUT KEPT THEM ON HIGH SIDE OF GUIDANCE. AFTER TROUGH PASSES FRIDAY TEMPERATURES SHOULD BE WARMING SATURDAY AND SUNDAY AHEAD OF A STRONGER WAVE THAT WILL ARRIVE LATE SUNDAY. KEPT FORECAST DRY IN WARM ADVECTION AHEAD OF THIS WAVE...BUT CAN NOT RULE OUT SOME NEED IN LATER FORECASTS. TRENDED MOST MAX TEMPERATURES UPWARD BOTH DAYS TO REFLECT FORECAST H85 TEMPS...BUT DIDN/T MIX TO THAT DEPTH DUE TO POSSIBLE CLOUDS. CHERMOK LONG TERM...SUNDAY NIGHT THROUGH THURSDAY. THE REGION WILL REMAIN IN NORTHWEST FLOW ALOFT AS A BROAD TROUGH REMAINS IN PLACE TO OUR EAST WHILE AN AMPLIFIED RIDGE REMAINS OVER THE WESTERN STATES. THIS WILL ALLOW A COLD CANADIAN AIRMASS TO DROP INTO THE NORTHERN PLAINS AND UPPER MIDWEST. THERE CONTINUES TO BE SOME DISAGREEMENT AS TO HOW FAR WEST THE COLD AIRMASS WILL REACH...HOWEVER THE TREND CONTINUES TO BE COLD FOR NEXT WEEK WITH HIGHS IN THE LOW 50S AND LOWS IN THE LOWER TO MID 30S. SOME WEAK RECOVERY BY THURSDAY MAY BRING HIGHS UP INTO THE MID TO UPPER 50S. KERN && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1222 PM CDT WED OCT 16 2013 .UPDATE... ISSUED AT 900 AM CDT WED OCT 16 2013 OUR MORNING LOW TEMPERATURES HAVE ALREADY BEEN REACHED AND TEMPERATURES ARE NOW RISING. THEREFORE...THE FROST AND FREEZE HEADLINES HAVE BEEN ALLOWED TO EXPIRE FOR ALL AREAS. TEMPERATURES WILL AGAIN BE VERY CHILLY TONIGHT AND FROST MAY AGAIN BE POSSIBLE IN SOME AREAS BY EARLY THURSDAY MORNING. UPDATE ISSUED AT 646 AM CDT WED OCT 16 2013 LITTLE CHANGE IN THINKING FROM A FEW HOURS AGO...AS ONE DECK OF MID CLOUDS CONTINUES SINKING SOUTHWARD ACROSS THE NORTHERN CWA...WHILE MAINLY THINNER/HIGHER CIRRUS CONTINUES INCREASING INTO AREAS NEAR/SOUTH OF THE STATE LINE. IN BETWEEN...MOST PLACES BETWEEN I-80 AND THE STATE LINE ARE ESSENTIALLY CLEAR AT THIS TIME. ALTHOUGH LIGHT BUT STEADY BREEZES HAVE LIKELY PRECLUDED TRULY WIDESPREAD FROST DEVELOPMENT IN MANY AREAS...PRESENT INDICATIONS ARE THAT THE FROST/FREEZE HEADLINES ISSUED YESTERDAY WERE JUSTIFIED ACROSS MOST AFFECTED AREAS...WITH A FEW LOWS SO FAR THIS MORNING CONSISTING OF 31 AT LEXINGTON AIRPORT...32 AT RAVENNA...HOLDREGE AIRPORT AND 4WNW PLAINVILLE KS...AND 33 AT HASTINGS AIRPORT. WITH CLOUDS ON THE INCREASE...ITS BECOMING INCREASINGLY UNLIKELY THAT FROST WILL BE OBSERVED IN THE HAMILTON/YORK AND JEWELL/MITCHELL COUNTY AREAS...BUT GIVEN THAT TEMPS ARE AT LEAST IN THE BALLPARK OF SUPPORTING FROST AT THIS TIME WILL DEFER TO ONCOMING DAY SHIFT TO FORMALLY PUT THESE HEADLINES TO REST. ONCE ALL MORNING TEMPERATURE REPORTS COME IN...DECISIONS WILL ALSO BE MADE REGARDING WHICH ADDITIONAL COUNTIES BESIDES VALLEY/GREELEY ARE DEEMED INELIGIBLE FOR FUTURE FROST/FREEZE HEADLINES...AS WE WILL LIKELY BE ADDING AT LEAST A FEW. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 430 AM CDT WED OCT 16 2013 COMPARED TO THE PAST 48 HOURS OF WIDESPREAD RAIN FOLLOWED BY FAIRLY STRONG NORTHWEST WINDS...THESE NEXT 24 HOURS ARE GOING TO BE A BENIGN CHANGE OF PACE...WITH ESSENTIALLY ZERO RISK OF MEASURABLE PRECIP AND SUSTAINED BREEZES STRUGGLING TO EXCEED 12 MPH AT MOST. HOWEVER...DUE TO FROST/FREEZE SENSITIVITIES THIS TIME OF YEAR...SKY COVER/CLOUD TRENDS HAVE TAKEN ON AN ENHANCED FORECAST FOCUS...GIVEN THE PRONOUNCED EFFECT OF CLOUD COVER ON TEMPERATURES. AS IT IS TURNING OUT...PARTS OF THE CWA ARE GOING TO FREEZE AND/OR FROST FAIRLY EFFICIENTLY THIS MORNING...WHILE OTHER PARTS OF THE AREA MAY ACTUALLY SEE MORE FAVORABLE CONDITIONS FOR FROST/FREEZE WEDNESDAY NIGHT INSTEAD. 07Z OBJECTIVE SURFACE ANALYSIS SHOWS THE LOCAL AREA POSITIONED BETWEEN A 1003 MILLIBAR LOW THAT HAS DEPARTED WELL EASTWARD INTO THE GREAT LAKES...AND A 1025 MILLIBAR HIGH CENTERED MUCH CLOSER TO HOME OVER THE NEB/KS/CO BORDER AREA. WITH THE PRESSURE GRADIENT CONTINUING TO RELAX...WEST-NORTHWEST BREEZES ACROSS MOST OF THIS CWA HAVE FINALLY EASED TO 10 MPH OR LESS...BUT WITH SLIGHTLY STRONGER SPEEDS STILL SHOWING UP NOW AND THEN MAINLY IN THE NORTHEAST. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA REVEAL THAT THE CWA IS POSITIONED ALMOST DIRECTLY UNDERNEATH A BROAD...SEVERELY POSITIVELY TILTED MID/UPPER LEVEL TROUGH AXIS EXTENDING IN A SOUTHWEST-NORTHEAST ORIENTATION FROM THE 4-CORNERS AREA THROUGH THE GREAT LAKES AND UP INTO EASTERN CANADA. ALONG THE SOUTHERN EDGE OF THIS TROUGH AXIS...A 105+ KT JET STREAK IS EVIDENT AT 300MB OVER THE KS/NEB BORDER. THE FOLLOWING PARAGRAPH FOCUSES SOLELY ON EXISTING FROST/FREEZE HEADLINES THIS MORNING...THE REAL HEADACHE THIS MORNING LIES WITH CLOUD COVER TRENDS PER IR AND 11-3.9 MICRON SATELLITE. ON A POSITIVE NOTE FOR CURRENT FROST/FREEZE HEADLINES...THE EXPANSIVE DECK OF LOW STRATUS THAT RULED MOST OF THE CWA ON TUESDAY CONTINUES TO STEADILY ERODE FROM NORTHWEST-TO-SOUTHEAST...WHICH MAKES IT NOW LOOK LIKE MUCH OF THE CWA SHOULD SEE AT LEAST A FEW HOURS OF CLEAR SKIES...POTENTIALLY ALLOWING FROST FORMATION TO COMMENCE. IN FACT...THIS PROCESS IS LIKELY ALREADY WELL-UNDERWAY IN/NEAR FAR WESTERN PORTIONS OF THE CWA...WHERE SITES SUCH AS LEXINGTON/MCCOOK HAVE ALREADY TUMBLED INTO THE LOW 30S THUS VERIFYING THE EXISTING FREEZE WARNING. HOWEVER...ON THE FLIP SIDE...PORTIONS OF THE ORIGINAL FROST ADVISORY ACROSS ROUGHLY THE EASTERN HALF OF THE CWA SEEMS TO BE FACING A GREATER OBSTACLE TO VERIFY...AS FOLLOWING SHORTLY BEHIND THE VACATING LOW STRATUS IS A SOUTHWARD-SINKING BAND OF MID LEVEL CLOUDS CENTERED BETWEEN 8-10K FEET...WHICH HAS ALREADY BRUSHED INTO THE FAR NORTHERN CWA...AND IS EXPECTED TO SLOWLY DROP SOUTHWARD TO AT LEAST ROUGHLY THE HIGHWAY 6 CORRIDOR BY SUNRISE. HOWEVER...THESE MID CLOUDS SHOULD HAVE LITTLE EFFECT ON EARLY MORNING TEMPERATURES ACROSS MOST OF THE SOUTHERN HALF TO ONE-THIRD OF THE CWA...WITH THESE AREAS LIKELY HEADED FOR SEVERAL HOURS OF CLEARING IN THE WAKE OF THE DEPARTING LOWER DECK. THE NET RESULT...AS IT CURRENTLY STANDS AT 09Z/4AM...IS THAT ADVISORIES/WARNINGS WERE CANCELLED FOR 5 COUNTIES NORTH OF INTERSTATE 80...WHILE AT LEAST FOR NOW WILL LET THE REMAINING 23 COUNTIES STAND AS-IS PER ORIGINAL ISSUANCE...AND TAKE ANOTHER LOOK FOR POSSIBLE UPDATES IN A FEW HOURS. TURNING TO OTHER ELEMENTS OF THE FORECAST...RIGHT OFF THE BAT DECIDED TO SLIP A SLIGHT CHANCE OF SPRINKLES INTO FAR NORTHERN AREAS UP AROUND ORD/GREELEY PRIOR TO SUNRISE TO ACCOUNT FOR A FEW WEAK RETURNS SHOWING UP ON RADAR UNDER THE INVADING MID-DECK...BUT THIS SHOULD BE VERY ISOLATED IN NATURE. BEYOND SUNRISE...ANTICIPATE A COOLISH BUT SEASONABLY PLEASANT DAY UNDER VARIABLE CLOUD COVER. ALOFT...THE AFOREMENTIONED ELONGATED MID LEVEL TROUGH AXIS WILL CONTINUE SLIPPING SOUTHWARD ACROSS THE REGION...AS A SHORTWAVE CURRENTLY WITHIN THE BASE OF THE TROUGH NEAR THE 4-CORNERS AREA GRADUALLY EJECTS EASTWARD ALONG THE KS/OK BORDER AS THE DAY WEARS ON. WHILE ANY SPOTTY RAIN FROM THIS DISTURBANCE SHOULD REMAIN WELL SOUTH OF THE LOCAL AREA...ESPECIALLY OUR KS ZONES COULD SEE A FAIR AMOUNT OF MID/UPPER LEVEL CLOUDS STREAMING EAST-NORTHEAST FROM THIS SYSTEM. MEANWHILE...THE ALREADY-PRESENT MID DECK SLIPPING INTO NORTHERN COUNTIES WILL CONTINUE TO SLOWLY SINK SOUTHWARD...AND IS EXPECTED TO PROVIDE A CLOUDY START TO THE DAY ACROSS THE MAJORITY OF NEB ZONES...BUT THEN ACCORDING TO 700 MILLIBAR RELATIVE HUMIDITY PROGS FROM THE RAP/NAM...SHOULD GRADUALLY FADE AWAY OR SCATTER OUT BY THE MID-LATE MORNING HOURS. SO...THE NET RESULT IS BEST PUT AS VARIABLE CLOUD COVER...AS NORTHERN AREAS SHOULD GENERALLY START OUT RATHER CLOUDY BUT SEE INCREASING SUN WITH TIME...WHILE SOUTHERN AREAS GENERALLY DO THE OPPOSITE AND SEE INCREASING CLOUDS WITH TIME. THESE CLOUD COVER TRENDS WILL BE TOUGH TO CAPTURE IN HOURLY FORECAST GRIDS...AND PLENTY OF UPDATES ARE LIKELY. OTHERWISE...AS THE CENTER OF THE SURFACE RIDGE AXIS SINKS SOUTH OF THE AREA TODAY...BREEZES WILL AVERAGE 10-12 MPH FROM THE WEST-NORTHWEST IN ALL AREAS. HIGH TEMPERATURES WERE ONLY TWEAKED SLIGHTLY PER A BLEND OF MET/MAV GUIDANCE AND RAP TEMPS...AND THUS WILL CONTINUE TO CALL FOR A REMARKABLY UNIFORM RANGE ACROSS THE CWA WITH ALL AREAS TOPPING OUT BETWEEN 56-59. FOR THIS EVENING/TONIGHT...THE MAIN STORY ALOFT IS THAT THE CURRENT SOUTHWEST-TO-NORTHEAST TROUGH AXIS WILL GRADUALLY BE REPLACED BY A SOUTHWEST-NORTHEAST ORIENTED SHORTWAVE RIDGE AXIS. THIS IS BECAUSE THE LOCAL AREA WILL BE IN BETWEEN TROUGHS...AS THE DISTURBANCE CENTERED OVER SOUTHERN KS AT SUNSET DEPARTS EASTWARD INTO MO...WHILE THE NEXT UPSTREAM TROUGH DROPPING SOUTHEAST TOWARD THE AREA ONLY REACHES AN AXIS FROM NORTHWEST CO TO NORTH DAKOTA BY SUNRISE THURSDAY. ALTHOUGH AM EXPECTING SKIES WEDNESDAY NIGHT AS A WHOLE TO AVERAGE CLEARER THAN THIS ONGOING NIGHT HAS BEEN...THERE IS AGAIN GOING TO BE VARIABLE CLOUD COVER EXCEPT THIS TIME SOLELY OF THE MID-UPPER VARIETY. FOR ONE...MAINLY SOUTHERN PARTS OF THE CWA WILL LIKELY START THE EVENING WITH LINGERING CLOUDS FROM THE DEPARTING DISTURBANCE...WHILE LATER IN THE NIGHT...MAINLY NORTHERN AREAS COULD SEE PASSING BATCHES OF CLOUDS OUT AHEAD OF THE APPROACHING UPSTREAM WAVE. MEANWHILE AT THE SURFACE...WINDS WILL REMAIN FAIRLY LIGHT AT SUSTAINED SPEEDS GENERALLY LESS THAN 8 MPH...BUT GRADUALLY TRANSITION FROM A SOUTHWESTERLY DIRECTION TO NORTHWESTERLY IN RESPONSE TO A SUBTLE PASSING TROUGH AXIS. AS FOR LOW TEMPS...ONCE AGAIN PASSING CLOUDS COULD POSE ISSUES...BUT FOR NOW STUCK VERY CLOSE TO A MET/MAV GUIDANCE BLEND...WHICH PUTS THE MAJORITY OF THE CWA DOWN BETWEEN 33-36 DEGREES...WITH THE TYPICALLY FAVORED DAWSON-TO-VALLEY COUNTY CORRIDOR MOST FAVORED TO SLIP SLIGHTLY BELOW FREEZING. OBVIOUSLY THESE LOWS ARE AGAIN SUPPORTIVE OF FROST AND/OR FREEZE DEVELOPMENT. HOWEVER...GIVEN THE ONGOING COMPLICATIONS/UNCERTAINTY THIS MORNING REGARDING LOW TEMPS...WILL HOLD OFF ON ANY WEDNESDAY NIGHT FROST ADVISORIES/FREEZE WARNINGS FOR NOW...NOT ONLY TO AVOID HEADLINE CONFUSION...BUT ALSO TO ALLOW DAY SHIFT TO IDENTIFY COUNTIES THAT COULD NOW BE RULED INELIGIBLE FROM FUTURE FROST/FREEZE HEADLINES BASED ON WHAT HAPPENS THIS MORNING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 430 AM CDT WED OCT 16 2013 MAIN CONCERNS THIS FORECAST PERIOD LOOKS TO BE PRECIPITATION CHANCES ON FRIDAY. STARTING OUT THURSDAY MORNING WITH THE BIG PICTURE...THERE SHOULD BE A HIGH AMPLITUDE RIDGE JUST OFF THE PACIFIC U.S. AND CANADIAN COAST WITH A LONG WAVE TROUGH AND SEVERAL EMBEDDED SHORT WAVES SITUATED OVER MUCH OF THE CONUS. THIS PATTERN WILL GRADUALLY SHIFT EAST A BIT BUT THE CENTRAL PLAINS SHOULD STILL BE SITTING ON THE BACK SIDE OF THE UPPER TROUGH BY NEXT TUESDAY...PUTTING US IN NORTHWEST FLOW. AT THE SURFACE ON TUESDAY MORNING...A TROUGH OF LOW PRESSURE EXTENDING FROM LAKE SUPERIOR TO THE OKLAHOMA PANHANDLE SHOULD BE JUST ABOUT THROUGH THE CWA WITH A WIND SHIFT FROM SOUTHWEST TO NORTHWEST. THE COOLER AIR WILL LAG BEHIND THE TROUGH A WAYS AND THURSDAY SHOULD BE QUITE NICE...JUST A FEW DEGREES LOWER THAN SEASONAL NORMALS. THE NEXT IN THE PROGRESSION OF MID LEVEL SHORTWAVES NOTED ABOVE IS THEN SLATED TO APPROACH THE PLAINS FROM THE NORTHWEST THURSDAY NIGHT INTO FRIDAY. SEVERAL MODELS SHOW A SIMILAR SOLUTION IN TAKING ONE WAVE NORTH AND EAST OF US AND DIGGING ANOTHER WAVE TO OUR WEST AND THEN SOUTH ACROSS KANSAS. INTERESTING TO RUN A TIME HEIGHT SECTION COMPARING THE GRAND ISLAND AREA TO THE PHILLIPSBURG KANSAS AREA IN TERMS OF MID LEVEL FORCING. THE NAM IS ONLY PRODUCING 1-2 UBARS PER SEC OF OMEGA OVER KGRI AT 12Z FRIDAY WHILE AT KPHG IT IS GENERATING 10-12 UBARS PER SEC. THE GFS HAS SIMILAR RESULTS FOR OUR SOUTHERN CWA WITH THE ONLY DIFFERENCE BEING THE GFS HAS A LITTLE LESS LOW LEVEL MOISTURE TO WORK WITH AND MAY TAKE A WHILE TO SATURATE THE COLUMN...WHILE THE NAM IS SATURATED ALL THE WAY FROM NEAR THE SURFACE TO 300 MB. THE EC FORECAST SOUNDING IS SIMILAR TO THE GFS AS IT IS NOT QUITE SATURATED UP TO 700MB. NEITHER THE GFS OR EC IS SHOWING THE LOWER PORTION BECOMING SATURATED BETWEEN 12 AND 18Z FRIDAY BUT I AM A LITTLE CONCERNED OF THE SCENARIO WHERE SNOW FALLING FROM ABOVE MOISTENS AND COOLS THE LOWER COLUMN UNTIL IT REACHES SATURATION. IF THIS WERE TO OCCUR...WE COULD SEE A LITTLE SNOW FRIDAY MORNING IN THE CWA. WILL NOT INCLUDE SNOW IN THE GRIDS FOR NOW AS I ONLY HAVE LOW TEMPERATURES FRIDAY MORNING FORECASTED TO BE AROUND 37 OR 38 DEGREES IN THE KANSAS PART OF OUR CWA...BUT IT WILL BE WORTH KEEPING AN EYE ON THE NEXT COUPLE OF DAYS. BUMPED UP POPS IN THE SOUTHERN PART OF THE CWA FOR FRIDAY AND THESE WILL NEED TO BE RAISED EVEN MORE IF THE MODELS REMAIN CONSISTENT ON THE TRACK OF THE SHORT WAVE TROUGH. THE COOLER AIR WILL THEN MAKE IT INTO THE AREA THURSDAY NIGHT AND BY FRIDAY HIGHS SHOULD BE 5 TO 10 DEGREES COOLER THAN ON THURSDAY. BUT THE COOLER WEATHER WILL ONLY LAST A DAY AS SATURDAY THROUGH TUESDAY SHOULD AGAIN BE IN THE UPPER 50S NORTH TO THE MID 60S SOUTH. WILL LEAVE REST OF FORECAST DRY FOR NOW BUT NOT TOTALLY OUT OF THE QUESTION THAT ONE OR TWO DISTURBANCES RIDING DOWN THE NORTHWEST FLOW MAY GIVE US AT LEAST A SLIGHT CHANCE FOR ADDITIONAL PRECIPITATION. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1223 PM CDT WED OCT 16 2013 SATELLITE SHOWS THAT THE BAND OF CLOUDS OVER THE KGRI TERMINAL AREA HAS BEEN THINNING OUT LATE THIS MORNING AND EARLY THIS AFTERNOON. EXPECT THERE TO BE SOME SCATTERED MID LEVEL CLOUDS ON AND OFF DURING THE NIGHT WITH AN INCREASE IN MID LEVEL CLOUDS LATE IN THE PERIOD. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...WESELY SHORT TERM...PFANNKUCH LONG TERM...EWALD AVIATION...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
907 AM CDT WED OCT 16 2013 .UPDATE... ISSUED AT 900 AM CDT WED OCT 16 2013 OUR MORNING LOW TEMPERATURES HAVE ALREADY BEEN REACHED AND TEMPERATURES ARE NOW RISING. THEREFORE...THE FROST AND FREEZE HEADLINES HAVE BEEN ALLOWED TO EXPIRE FOR ALL AREAS. TEMPERATURES WILL AGAIN BE VERY CHILLY TONIGHT AND FROST MAY AGAIN BE POSSIBLE IN SOME AREAS BY EARLY THURSDAY MORNING. UPDATE ISSUED AT 646 AM CDT WED OCT 16 2013 LITTLE CHANGE IN THINKING FROM A FEW HOURS AGO...AS ONE DECK OF MID CLOUDS CONTINUES SINKING SOUTHWARD ACROSS THE NORTHERN CWA...WHILE MAINLY THINNER/HIGHER CIRRUS CONTINUES INCREASING INTO AREAS NEAR/SOUTH OF THE STATE LINE. IN BETWEEN...MOST PLACES BETWEEN I-80 AND THE STATE LINE ARE ESSENTIALLY CLEAR AT THIS TIME. ALTHOUGH LIGHT BUT STEADY BREEZES HAVE LIKELY PRECLUDED TRULY WIDESPREAD FROST DEVELOPMENT IN MANY AREAS...PRESENT INDICATIONS ARE THAT THE FROST/FREEZE HEADLINES ISSUED YESTERDAY WERE JUSTIFIED ACROSS MOST AFFECTED AREAS...WITH A FEW LOWS SO FAR THIS MORNING CONSISTING OF 31 AT LEXINGTON AIRPORT...32 AT RAVENNA...HOLDREGE AIRPORT AND 4WNW PLAINVILLE KS...AND 33 AT HASTINGS AIRPORT. WITH CLOUDS ON THE INCREASE...ITS BECOMING INCREASINGLY UNLIKELY THAT FROST WILL BE OBSERVED IN THE HAMILTON/YORK AND JEWELL/MITCHELL COUNTY AREAS...BUT GIVEN THAT TEMPS ARE AT LEAST IN THE BALLPARK OF SUPPORTING FROST AT THIS TIME WILL DEFER TO ONCOMING DAY SHIFT TO FORMALLY PUT THESE HEADLINES TO REST. ONCE ALL MORNING TEMPERATURE REPORTS COME IN...DECISIONS WILL ALSO BE MADE REGARDING WHICH ADDITIONAL COUNTIES BESIDES VALLEY/GREELEY ARE DEEMED INELIGIBLE FOR FUTURE FROST/FREEZE HEADLINES...AS WE WILL LIKELY BE ADDING AT LEAST A FEW. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 430 AM CDT WED OCT 16 2013 COMPARED TO THE PAST 48 HOURS OF WIDESPREAD RAIN FOLLOWED BY FAIRLY STRONG NORTHWEST WINDS...THESE NEXT 24 HOURS ARE GOING TO BE A BENIGN CHANGE OF PACE...WITH ESSENTIALLY ZERO RISK OF MEASURABLE PRECIP AND SUSTAINED BREEZES STRUGGLING TO EXCEED 12 MPH AT MOST. HOWEVER...DUE TO FROST/FREEZE SENSITIVITIES THIS TIME OF YEAR...SKY COVER/CLOUD TRENDS HAVE TAKEN ON AN ENHANCED FORECAST FOCUS...GIVEN THE PRONOUNCED EFFECT OF CLOUD COVER ON TEMPERATURES. AS IT IS TURNING OUT...PARTS OF THE CWA ARE GOING TO FREEZE AND/OR FROST FAIRLY EFFICIENTLY THIS MORNING...WHILE OTHER PARTS OF THE AREA MAY ACTUALLY SEE MORE FAVORABLE CONDITIONS FOR FROST/FREEZE WEDNESDAY NIGHT INSTEAD. 07Z OBJECTIVE SURFACE ANALYSIS SHOWS THE LOCAL AREA POSITIONED BETWEEN A 1003 MILLIBAR LOW THAT HAS DEPARTED WELL EASTWARD INTO THE GREAT LAKES...AND A 1025 MILLIBAR HIGH CENTERED MUCH CLOSER TO HOME OVER THE NEB/KS/CO BORDER AREA. WITH THE PRESSURE GRADIENT CONTINUING TO RELAX...WEST-NORTHWEST BREEZES ACROSS MOST OF THIS CWA HAVE FINALLY EASED TO 10 MPH OR LESS...BUT WITH SLIGHTLY STRONGER SPEEDS STILL SHOWING UP NOW AND THEN MAINLY IN THE NORTHEAST. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA REVEAL THAT THE CWA IS POSITIONED ALMOST DIRECTLY UNDERNEATH A BROAD...SEVERELY POSITIVELY TILTED MID/UPPER LEVEL TROUGH AXIS EXTENDING IN A SOUTHWEST-NORTHEAST ORIENTATION FROM THE 4-CORNERS AREA THROUGH THE GREAT LAKES AND UP INTO EASTERN CANADA. ALONG THE SOUTHERN EDGE OF THIS TROUGH AXIS...A 105+ KT JET STREAK IS EVIDENT AT 300MB OVER THE KS/NEB BORDER. THE FOLLOWING PARAGRAPH FOCUSES SOLELY ON EXISTING FROST/FREEZE HEADLINES THIS MORNING...THE REAL HEADACHE THIS MORNING LIES WITH CLOUD COVER TRENDS PER IR AND 11-3.9 MICRON SATELLITE. ON A POSITIVE NOTE FOR CURRENT FROST/FREEZE HEADLINES...THE EXPANSIVE DECK OF LOW STRATUS THAT RULED MOST OF THE CWA ON TUESDAY CONTINUES TO STEADILY ERODE FROM NORTHWEST-TO-SOUTHEAST...WHICH MAKES IT NOW LOOK LIKE MUCH OF THE CWA SHOULD SEE AT LEAST A FEW HOURS OF CLEAR SKIES...POTENTIALLY ALLOWING FROST FORMATION TO COMMENCE. IN FACT...THIS PROCESS IS LIKELY ALREADY WELL-UNDERWAY IN/NEAR FAR WESTERN PORTIONS OF THE CWA...WHERE SITES SUCH AS LEXINGTON/MCCOOK HAVE ALREADY TUMBLED INTO THE LOW 30S THUS VERIFYING THE EXISTING FREEZE WARNING. HOWEVER...ON THE FLIP SIDE...PORTIONS OF THE ORIGINAL FROST ADVISORY ACROSS ROUGHLY THE EASTERN HALF OF THE CWA SEEMS TO BE FACING A GREATER OBSTACLE TO VERIFY...AS FOLLOWING SHORTLY BEHIND THE VACATING LOW STRATUS IS A SOUTHWARD-SINKING BAND OF MID LEVEL CLOUDS CENTERED BETWEEN 8-10K FEET...WHICH HAS ALREADY BRUSHED INTO THE FAR NORTHERN CWA...AND IS EXPECTED TO SLOWLY DROP SOUTHWARD TO AT LEAST ROUGHLY THE HIGHWAY 6 CORRIDOR BY SUNRISE. HOWEVER...THESE MID CLOUDS SHOULD HAVE LITTLE EFFECT ON EARLY MORNING TEMPERATURES ACROSS MOST OF THE SOUTHERN HALF TO ONE-THIRD OF THE CWA...WITH THESE AREAS LIKELY HEADED FOR SEVERAL HOURS OF CLEARING IN THE WAKE OF THE DEPARTING LOWER DECK. THE NET RESULT...AS IT CURRENTLY STANDS AT 09Z/4AM...IS THAT ADVISORIES/WARNINGS WERE CANCELLED FOR 5 COUNTIES NORTH OF INTERSTATE 80...WHILE AT LEAST FOR NOW WILL LET THE REMAINING 23 COUNTIES STAND AS-IS PER ORIGINAL ISSUANCE...AND TAKE ANOTHER LOOK FOR POSSIBLE UPDATES IN A FEW HOURS. TURNING TO OTHER ELEMENTS OF THE FORECAST...RIGHT OFF THE BAT DECIDED TO SLIP A SLIGHT CHANCE OF SPRINKLES INTO FAR NORTHERN AREAS UP AROUND ORD/GREELEY PRIOR TO SUNRISE TO ACCOUNT FOR A FEW WEAK RETURNS SHOWING UP ON RADAR UNDER THE INVADING MID-DECK...BUT THIS SHOULD BE VERY ISOLATED IN NATURE. BEYOND SUNRISE...ANTICIPATE A COOLISH BUT SEASONABLY PLEASANT DAY UNDER VARIABLE CLOUD COVER. ALOFT...THE AFOREMENTIONED ELONGATED MID LEVEL TROUGH AXIS WILL CONTINUE SLIPPING SOUTHWARD ACROSS THE REGION...AS A SHORTWAVE CURRENTLY WITHIN THE BASE OF THE TROUGH NEAR THE 4-CORNERS AREA GRADUALLY EJECTS EASTWARD ALONG THE KS/OK BORDER AS THE DAY WEARS ON. WHILE ANY SPOTTY RAIN FROM THIS DISTURBANCE SHOULD REMAIN WELL SOUTH OF THE LOCAL AREA...ESPECIALLY OUR KS ZONES COULD SEE A FAIR AMOUNT OF MID/UPPER LEVEL CLOUDS STREAMING EAST-NORTHEAST FROM THIS SYSTEM. MEANWHILE...THE ALREADY-PRESENT MID DECK SLIPPING INTO NORTHERN COUNTIES WILL CONTINUE TO SLOWLY SINK SOUTHWARD...AND IS EXPECTED TO PROVIDE A CLOUDY START TO THE DAY ACROSS THE MAJORITY OF NEB ZONES...BUT THEN ACCORDING TO 700 MILLIBAR RELATIVE HUMIDITY PROGS FROM THE RAP/NAM...SHOULD GRADUALLY FADE AWAY OR SCATTER OUT BY THE MID-LATE MORNING HOURS. SO...THE NET RESULT IS BEST PUT AS VARIABLE CLOUD COVER...AS NORTHERN AREAS SHOULD GENERALLY START OUT RATHER CLOUDY BUT SEE INCREASING SUN WITH TIME...WHILE SOUTHERN AREAS GENERALLY DO THE OPPOSITE AND SEE INCREASING CLOUDS WITH TIME. THESE CLOUD COVER TRENDS WILL BE TOUGH TO CAPTURE IN HOURLY FORECAST GRIDS...AND PLENTY OF UPDATES ARE LIKELY. OTHERWISE...AS THE CENTER OF THE SURFACE RIDGE AXIS SINKS SOUTH OF THE AREA TODAY...BREEZES WILL AVERAGE 10-12 MPH FROM THE WEST-NORTHWEST IN ALL AREAS. HIGH TEMPERATURES WERE ONLY TWEAKED SLIGHTLY PER A BLEND OF MET/MAV GUIDANCE AND RAP TEMPS...AND THUS WILL CONTINUE TO CALL FOR A REMARKABLY UNIFORM RANGE ACROSS THE CWA WITH ALL AREAS TOPPING OUT BETWEEN 56-59. FOR THIS EVENING/TONIGHT...THE MAIN STORY ALOFT IS THAT THE CURRENT SOUTHWEST-TO-NORTHEAST TROUGH AXIS WILL GRADUALLY BE REPLACED BY A SOUTHWEST-NORTHEAST ORIENTED SHORTWAVE RIDGE AXIS. THIS IS BECAUSE THE LOCAL AREA WILL BE IN BETWEEN TROUGHS...AS THE DISTURBANCE CENTERED OVER SOUTHERN KS AT SUNSET DEPARTS EASTWARD INTO MO...WHILE THE NEXT UPSTREAM TROUGH DROPPING SOUTHEAST TOWARD THE AREA ONLY REACHES AN AXIS FROM NORTHWEST CO TO NORTH DAKOTA BY SUNRISE THURSDAY. ALTHOUGH AM EXPECTING SKIES WEDNESDAY NIGHT AS A WHOLE TO AVERAGE CLEARER THAN THIS ONGOING NIGHT HAS BEEN...THERE IS AGAIN GOING TO BE VARIABLE CLOUD COVER EXCEPT THIS TIME SOLELY OF THE MID-UPPER VARIETY. FOR ONE...MAINLY SOUTHERN PARTS OF THE CWA WILL LIKELY START THE EVENING WITH LINGERING CLOUDS FROM THE DEPARTING DISTURBANCE...WHILE LATER IN THE NIGHT...MAINLY NORTHERN AREAS COULD SEE PASSING BATCHES OF CLOUDS OUT AHEAD OF THE APPROACHING UPSTREAM WAVE. MEANWHILE AT THE SURFACE...WINDS WILL REMAIN FAIRLY LIGHT AT SUSTAINED SPEEDS GENERALLY LESS THAN 8 MPH...BUT GRADUALLY TRANSITION FROM A SOUTHWESTERLY DIRECTION TO NORTHWESTERLY IN RESPONSE TO A SUBTLE PASSING TROUGH AXIS. AS FOR LOW TEMPS...ONCE AGAIN PASSING CLOUDS COULD POSE ISSUES...BUT FOR NOW STUCK VERY CLOSE TO A MET/MAV GUIDANCE BLEND...WHICH PUTS THE MAJORITY OF THE CWA DOWN BETWEEN 33-36 DEGREES...WITH THE TYPICALLY FAVORED DAWSON-TO-VALLEY COUNTY CORRIDOR MOST FAVORED TO SLIP SLIGHTLY BELOW FREEZING. OBVIOUSLY THESE LOWS ARE AGAIN SUPPORTIVE OF FROST AND/OR FREEZE DEVELOPMENT. HOWEVER...GIVEN THE ONGOING COMPLICATIONS/UNCERTAINTY THIS MORNING REGARDING LOW TEMPS...WILL HOLD OFF ON ANY WEDNESDAY NIGHT FROST ADVISORIES/FREEZE WARNINGS FOR NOW...NOT ONLY TO AVOID HEADLINE CONFUSION...BUT ALSO TO ALLOW DAY SHIFT TO IDENTIFY COUNTIES THAT COULD NOW BE RULED INELIGIBLE FROM FUTURE FROST/FREEZE HEADLINES BASED ON WHAT HAPPENS THIS MORNING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 430 AM CDT WED OCT 16 2013 MAIN CONCERNS THIS FORECAST PERIOD LOOKS TO BE PRECIPITATION CHANCES ON FRIDAY. STARTING OUT THURSDAY MORNING WITH THE BIG PICTURE...THERE SHOULD BE A HIGH AMPLITUDE RIDGE JUST OFF THE PACIFIC U.S. AND CANADIAN COAST WITH A LONG WAVE TROUGH AND SEVERAL EMBEDDED SHORT WAVES SITUATED OVER MUCH OF THE CONUS. THIS PATTERN WILL GRADUALLY SHIFT EAST A BIT BUT THE CENTRAL PLAINS SHOULD STILL BE SITTING ON THE BACK SIDE OF THE UPPER TROUGH BY NEXT TUESDAY...PUTTING US IN NORTHWEST FLOW. AT THE SURFACE ON TUESDAY MORNING...A TROUGH OF LOW PRESSURE EXTENDING FROM LAKE SUPERIOR TO THE OKLAHOMA PANHANDLE SHOULD BE JUST ABOUT THROUGH THE CWA WITH A WIND SHIFT FROM SOUTHWEST TO NORTHWEST. THE COOLER AIR WILL LAG BEHIND THE TROUGH A WAYS AND THURSDAY SHOULD BE QUITE NICE...JUST A FEW DEGREES LOWER THAN SEASONAL NORMALS. THE NEXT IN THE PROGRESSION OF MID LEVEL SHORTWAVES NOTED ABOVE IS THEN SLATED TO APPROACH THE PLAINS FROM THE NORTHWEST THURSDAY NIGHT INTO FRIDAY. SEVERAL MODELS SHOW A SIMILAR SOLUTION IN TAKING ONE WAVE NORTH AND EAST OF US AND DIGGING ANOTHER WAVE TO OUR WEST AND THEN SOUTH ACROSS KANSAS. INTERESTING TO RUN A TIME HEIGHT SECTION COMPARING THE GRAND ISLAND AREA TO THE PHILLIPSBURG KANSAS AREA IN TERMS OF MID LEVEL FORCING. THE NAM IS ONLY PRODUCING 1-2 UBARS PER SEC OF OMEGA OVER KGRI AT 12Z FRIDAY WHILE AT KPHG IT IS GENERATING 10-12 UBARS PER SEC. THE GFS HAS SIMILAR RESULTS FOR OUR SOUTHERN CWA WITH THE ONLY DIFFERENCE BEING THE GFS HAS A LITTLE LESS LOW LEVEL MOISTURE TO WORK WITH AND MAY TAKE A WHILE TO SATURATE THE COLUMN...WHILE THE NAM IS SATURATED ALL THE WAY FROM NEAR THE SURFACE TO 300 MB. THE EC FORECAST SOUNDING IS SIMILAR TO THE GFS AS IT IS NOT QUITE SATURATED UP TO 700MB. NEITHER THE GFS OR EC IS SHOWING THE LOWER PORTION BECOMING SATURATED BETWEEN 12 AND 18Z FRIDAY BUT I AM A LITTLE CONCERNED OF THE SCENARIO WHERE SNOW FALLING FROM ABOVE MOISTENS AND COOLS THE LOWER COLUMN UNTIL IT REACHES SATURATION. IF THIS WERE TO OCCUR...WE COULD SEE A LITTLE SNOW FRIDAY MORNING IN THE CWA. WILL NOT INCLUDE SNOW IN THE GRIDS FOR NOW AS I ONLY HAVE LOW TEMPERATURES FRIDAY MORNING FORECASTED TO BE AROUND 37 OR 38 DEGREES IN THE KANSAS PART OF OUR CWA...BUT IT WILL BE WORTH KEEPING AN EYE ON THE NEXT COUPLE OF DAYS. BUMPED UP POPS IN THE SOUTHERN PART OF THE CWA FOR FRIDAY AND THESE WILL NEED TO BE RAISED EVEN MORE IF THE MODELS REMAIN CONSISTENT ON THE TRACK OF THE SHORT WAVE TROUGH. THE COOLER AIR WILL THEN MAKE IT INTO THE AREA THURSDAY NIGHT AND BY FRIDAY HIGHS SHOULD BE 5 TO 10 DEGREES COOLER THAN ON THURSDAY. BUT THE COOLER WEATHER WILL ONLY LAST A DAY AS SATURDAY THROUGH TUESDAY SHOULD AGAIN BE IN THE UPPER 50S NORTH TO THE MID 60S SOUTH. WILL LEAVE REST OF FORECAST DRY FOR NOW BUT NOT TOTALLY OUT OF THE QUESTION THAT ONE OR TWO DISTURBANCES RIDING DOWN THE NORTHWEST FLOW MAY GIVE US AT LEAST A SLIGHT CHANCE FOR ADDITIONAL PRECIPITATION. && .AVIATION...(FOR THE 12Z KGRI TAF THROUGH 12Z THURSDAY MORNING) ISSUED AT 550 AM CDT WED OCT 16 2013 COMPARED TO THE PAST FEW DAYS...THE UPCOMING PERIOD WILL BE MARKED BY MUCH MORE TRANQUIL AVIATION WEATHER IN SOUTH CENTRAL NEBRASKA. DESPITE PASSING BATCHES OF MID LEVEL CLOUDS CENTERED NEAR/ABOVE 9000 FT...THERE IS HIGH CONFIDENCE IN VFR CONDITIONS THROUGHOUT...AND ESSENTIALLY ZERO RISK OF PRECIPITATION. AS FOR SURFACE WINDS...SPEEDS WILL AVERAGE AT/BELOW 11KT FROM THE WEST- NORTHWEST TODAY BEFORE BECOMING LIGHTER AND SOMEWHAT VARIABLE IN DIRECTION THIS EVENING/TONIGHT...WITH THE ADVERTISED DIRECTION OF 240 DEGREES AFTER 00Z REPRESENTING AN AVERAGE DIRECTION FOR THE NIGHT. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...WESELY SHORT TERM...PFANNKUCH LONG TERM...EWALD AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS HASTINGS NE
647 AM CDT WED OCT 16 2013 .UPDATE... ISSUED AT 646 AM CDT WED OCT 16 2013 LITTLE CHANGE IN THINKING FROM A FEW HOURS AGO...AS ONE DECK OF MID CLOUDS CONTINUES SINKING SOUTHWARD ACROSS THE NORTHERN CWA...WHILE MAINLY THINNER/HIGHER CIRRUS CONTINUES INCREASING INTO AREAS NEAR/SOUTH OF THE STATE LINE. IN BETWEEN...MOST PLACES BETWEEN I-80 AND THE STATE LINE ARE ESSENTIALLY CLEAR AT THIS TIME. ALTHOUGH LIGHT BUT STEADY BREEZES HAVE LIKELY PRECLUDED TRULY WIDESPREAD FROST DEVELOPMENT IN MANY AREAS...PRESENT INDICATIONS ARE THAT THE FROST/FREEZE HEADLINES ISSUED YESTERDAY WERE JUSTIFIED ACROSS MOST AFFECTED AREAS...WITH A FEW LOWS SO FAR THIS MORNING CONSISTING OF 31 AT LEXINGTON AIRPORT...32 AT RAVENNA...HOLDREGE AIRPORT AND 4WNW PLAINVILLE KS...AND 33 AT HASTINGS AIRPORT. WITH CLOUDS ON THE INCREASE...ITS BECOMING INCREASINGLY UNLIKELY THAT FROST WILL BE OBSERVED IN THE HAMILTON/YORK AND JEWELL/MITCHELL COUNTY AREAS...BUT GIVEN THAT TEMPS ARE AT LEAST IN THE BALLPARK OF SUPPORTING FROST AT THIS TIME WILL DEFER TO ONCOMING DAY SHIFT TO FORMALLY PUT THESE HEADLINES TO REST. ONCE ALL MORNING TEMPERATURE REPORTS COME IN...DECISIONS WILL ALSO BE MADE REGARDING WHICH ADDITIONAL COUNTIES BESIDES VALLEY/GREELEY ARE DEEMED INELIGIBLE FOR FUTURE FROST/FREEZE HEADLINES...AS WE WILL LIKELY BE ADDING AT LEAST A FEW. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 430 AM CDT WED OCT 16 2013 COMPARED TO THE PAST 48 HOURS OF WIDESPREAD RAIN FOLLOWED BY FAIRLY STRONG NORTHWEST WINDS...THESE NEXT 24 HOURS ARE GOING TO BE A BENIGN CHANGE OF PACE...WITH ESSENTIALLY ZERO RISK OF MEASURABLE PRECIP AND SUSTAINED BREEZES STRUGGLING TO EXCEED 12 MPH AT MOST. HOWEVER...DUE TO FROST/FREEZE SENSITIVITIES THIS TIME OF YEAR...SKY COVER/CLOUD TRENDS HAVE TAKEN ON AN ENHANCED FORECAST FOCUS...GIVEN THE PRONOUNCED EFFECT OF CLOUD COVER ON TEMPERATURES. AS IT IS TURNING OUT...PARTS OF THE CWA ARE GOING TO FREEZE AND/OR FROST FAIRLY EFFICIENTLY THIS MORNING...WHILE OTHER PARTS OF THE AREA MAY ACTUALLY SEE MORE FAVORABLE CONDITIONS FOR FROST/FREEZE WEDNESDAY NIGHT INSTEAD. 07Z OBJECTIVE SURFACE ANALYSIS SHOWS THE LOCAL AREA POSITIONED BETWEEN A 1003 MILLIBAR LOW THAT HAS DEPARTED WELL EASTWARD INTO THE GREAT LAKES...AND A 1025 MILLIBAR HIGH CENTERED MUCH CLOSER TO HOME OVER THE NEB/KS/CO BORDER AREA. WITH THE PRESSURE GRADIENT CONTINUING TO RELAX...WEST-NORTHWEST BREEZES ACROSS MOST OF THIS CWA HAVE FINALLY EASED TO 10 MPH OR LESS...BUT WITH SLIGHTLY STRONGER SPEEDS STILL SHOWING UP NOW AND THEN MAINLY IN THE NORTHEAST. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA REVEAL THAT THE CWA IS POSITIONED ALMOST DIRECTLY UNDERNEATH A BROAD...SEVERELY POSITIVELY TILTED MID/UPPER LEVEL TROUGH AXIS EXTENDING IN A SOUTHWEST-NORTHEAST ORIENTATION FROM THE 4-CORNERS AREA THROUGH THE GREAT LAKES AND UP INTO EASTERN CANADA. ALONG THE SOUTHERN EDGE OF THIS TROUGH AXIS...A 105+ KT JET STREAK IS EVIDENT AT 300MB OVER THE KS/NEB BORDER. THE FOLLOWING PARAGRAPH FOCUSES SOLELY ON EXISTING FROST/FREEZE HEADLINES THIS MORNING...THE REAL HEADACHE THIS MORNING LIES WITH CLOUD COVER TRENDS PER IR AND 11-3.9 MICRON SATELLITE. ON A POSITIVE NOTE FOR CURRENT FROST/FREEZE HEADLINES...THE EXPANSIVE DECK OF LOW STRATUS THAT RULED MOST OF THE CWA ON TUESDAY CONTINUES TO STEADILY ERODE FROM NORTHWEST-TO-SOUTHEAST...WHICH MAKES IT NOW LOOK LIKE MUCH OF THE CWA SHOULD SEE AT LEAST A FEW HOURS OF CLEAR SKIES...POTENTIALLY ALLOWING FROST FORMATION TO COMMENCE. IN FACT...THIS PROCESS IS LIKELY ALREADY WELL-UNDERWAY IN/NEAR FAR WESTERN PORTIONS OF THE CWA...WHERE SITES SUCH AS LEXINGTON/MCCOOK HAVE ALREADY TUMBLED INTO THE LOW 30S THUS VERIFYING THE EXISTING FREEZE WARNING. HOWEVER...ON THE FLIP SIDE...PORTIONS OF THE ORIGINAL FROST ADVISORY ACROSS ROUGHLY THE EASTERN HALF OF THE CWA SEEMS TO BE FACING A GREATER OBSTACLE TO VERIFY...AS FOLLOWING SHORTLY BEHIND THE VACATING LOW STRATUS IS A SOUTHWARD-SINKING BAND OF MID LEVEL CLOUDS CENTERED BETWEEN 8-10K FEET...WHICH HAS ALREADY BRUSHED INTO THE FAR NORTHERN CWA...AND IS EXPECTED TO SLOWLY DROP SOUTHWARD TO AT LEAST ROUGHLY THE HIGHWAY 6 CORRIDOR BY SUNRISE. HOWEVER...THESE MID CLOUDS SHOULD HAVE LITTLE EFFECT ON EARLY MORNING TEMPERATURES ACROSS MOST OF THE SOUTHERN HALF TO ONE-THIRD OF THE CWA...WITH THESE AREAS LIKELY HEADED FOR SEVERAL HOURS OF CLEARING IN THE WAKE OF THE DEPARTING LOWER DECK. THE NET RESULT...AS IT CURRENTLY STANDS AT 09Z/4AM...IS THAT ADVISORIES/WARNINGS WERE CANCELLED FOR 5 COUNTIES NORTH OF INTERSTATE 80...WHILE AT LEAST FOR NOW WILL LET THE REMAINING 23 COUNTIES STAND AS-IS PER ORIGINAL ISSUANCE...AND TAKE ANOTHER LOOK FOR POSSIBLE UPDATES IN A FEW HOURS. TURNING TO OTHER ELEMENTS OF THE FORECAST...RIGHT OFF THE BAT DECIDED TO SLIP A SLIGHT CHANCE OF SPRINKLES INTO FAR NORTHERN AREAS UP AROUND ORD/GREELEY PRIOR TO SUNRISE TO ACCOUNT FOR A FEW WEAK RETURNS SHOWING UP ON RADAR UNDER THE INVADING MID-DECK...BUT THIS SHOULD BE VERY ISOLATED IN NATURE. BEYOND SUNRISE...ANTICIPATE A COOLISH BUT SEASONABLY PLEASANT DAY UNDER VARIABLE CLOUD COVER. ALOFT...THE AFOREMENTIONED ELONGATED MID LEVEL TROUGH AXIS WILL CONTINUE SLIPPING SOUTHWARD ACROSS THE REGION...AS A SHORTWAVE CURRENTLY WITHIN THE BASE OF THE TROUGH NEAR THE 4-CORNERS AREA GRADUALLY EJECTS EASTWARD ALONG THE KS/OK BORDER AS THE DAY WEARS ON. WHILE ANY SPOTTY RAIN FROM THIS DISTURBANCE SHOULD REMAIN WELL SOUTH OF THE LOCAL AREA...ESPECIALLY OUR KS ZONES COULD SEE A FAIR AMOUNT OF MID/UPPER LEVEL CLOUDS STREAMING EAST-NORTHEAST FROM THIS SYSTEM. MEANWHILE...THE ALREADY-PRESENT MID DECK SLIPPING INTO NORTHERN COUNTIES WILL CONTINUE TO SLOWLY SINK SOUTHWARD...AND IS EXPECTED TO PROVIDE A CLOUDY START TO THE DAY ACROSS THE MAJORITY OF NEB ZONES...BUT THEN ACCORDING TO 700 MILLIBAR RELATIVE HUMIDITY PROGS FROM THE RAP/NAM...SHOULD GRADUALLY FADE AWAY OR SCATTER OUT BY THE MID-LATE MORNING HOURS. SO...THE NET RESULT IS BEST PUT AS VARIABLE CLOUD COVER...AS NORTHERN AREAS SHOULD GENERALLY START OUT RATHER CLOUDY BUT SEE INCREASING SUN WITH TIME...WHILE SOUTHERN AREAS GENERALLY DO THE OPPOSITE AND SEE INCREASING CLOUDS WITH TIME. THESE CLOUD COVER TRENDS WILL BE TOUGH TO CAPTURE IN HOURLY FORECAST GRIDS...AND PLENTY OF UPDATES ARE LIKELY. OTHERWISE...AS THE CENTER OF THE SURFACE RIDGE AXIS SINKS SOUTH OF THE AREA TODAY...BREEZES WILL AVERAGE 10-12 MPH FROM THE WEST-NORTHWEST IN ALL AREAS. HIGH TEMPERATURES WERE ONLY TWEAKED SLIGHTLY PER A BLEND OF MET/MAV GUIDANCE AND RAP TEMPS...AND THUS WILL CONTINUE TO CALL FOR A REMARKABLY UNIFORM RANGE ACROSS THE CWA WITH ALL AREAS TOPPING OUT BETWEEN 56-59. FOR THIS EVENING/TONIGHT...THE MAIN STORY ALOFT IS THAT THE CURRENT SOUTHWEST-TO-NORTHEAST TROUGH AXIS WILL GRADUALLY BE REPLACED BY A SOUTHWEST-NORTHEAST ORIENTED SHORTWAVE RIDGE AXIS. THIS IS BECAUSE THE LOCAL AREA WILL BE IN BETWEEN TROUGHS...AS THE DISTURBANCE CENTERED OVER SOUTHERN KS AT SUNSET DEPARTS EASTWARD INTO MO...WHILE THE NEXT UPSTREAM TROUGH DROPPING SOUTHEAST TOWARD THE AREA ONLY REACHES AN AXIS FROM NORTHWEST CO TO NORTH DAKOTA BY SUNRISE THURSDAY. ALTHOUGH AM EXPECTING SKIES WEDNESDAY NIGHT AS A WHOLE TO AVERAGE CLEARER THAN THIS ONGOING NIGHT HAS BEEN...THERE IS AGAIN GOING TO BE VARIABLE CLOUD COVER EXCEPT THIS TIME SOLELY OF THE MID-UPPER VARIETY. FOR ONE...MAINLY SOUTHERN PARTS OF THE CWA WILL LIKELY START THE EVENING WITH LINGERING CLOUDS FROM THE DEPARTING DISTURBANCE...WHILE LATER IN THE NIGHT...MAINLY NORTHERN AREAS COULD SEE PASSING BATCHES OF CLOUDS OUT AHEAD OF THE APPROACHING UPSTREAM WAVE. MEANWHILE AT THE SURFACE...WINDS WILL REMAIN FAIRLY LIGHT AT SUSTAINED SPEEDS GENERALLY LESS THAN 8 MPH...BUT GRADUALLY TRANSITION FROM A SOUTHWESTERLY DIRECTION TO NORTHWESTERLY IN RESPONSE TO A SUBTLE PASSING TROUGH AXIS. AS FOR LOW TEMPS...ONCE AGAIN PASSING CLOUDS COULD POSE ISSUES...BUT FOR NOW STUCK VERY CLOSE TO A MET/MAV GUIDANCE BLEND...WHICH PUTS THE MAJORITY OF THE CWA DOWN BETWEEN 33-36 DEGREES...WITH THE TYPICALLY FAVORED DAWSON-TO-VALLEY COUNTY CORRIDOR MOST FAVORED TO SLIP SLIGHTLY BELOW FREEZING. OBVIOUSLY THESE LOWS ARE AGAIN SUPPORTIVE OF FROST AND/OR FREEZE DEVELOPMENT. HOWEVER...GIVEN THE ONGOING COMPLICATIONS/UNCERTAINTY THIS MORNING REGARDING LOW TEMPS...WILL HOLD OFF ON ANY WEDNESDAY NIGHT FROST ADVISORIES/FREEZE WARNINGS FOR NOW...NOT ONLY TO AVOID HEADLINE CONFUSION...BUT ALSO TO ALLOW DAY SHIFT TO IDENTIFY COUNTIES THAT COULD NOW BE RULED INELIGIBLE FROM FUTURE FROST/FREEZE HEADLINES BASED ON WHAT HAPPENS THIS MORNING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 430 AM CDT WED OCT 16 2013 MAIN CONCERNS THIS FORECAST PERIOD LOOKS TO BE PRECIPITATION CHANCES ON FRIDAY. STARTING OUT THURSDAY MORNING WITH THE BIG PICTURE...THERE SHOULD BE A HIGH AMPLITUDE RIDGE JUST OFF THE PACIFIC U.S. AND CANADIAN COAST WITH A LONG WAVE TROUGH AND SEVERAL EMBEDDED SHORT WAVES SITUATED OVER MUCH OF THE CONUS. THIS PATTERN WILL GRADUALLY SHIFT EAST A BIT BUT THE CENTRAL PLAINS SHOULD STILL BE SITTING ON THE BACK SIDE OF THE UPPER TROUGH BY NEXT TUESDAY...PUTTING US IN NORTHWEST FLOW. AT THE SURFACE ON TUESDAY MORNING...A TROUGH OF LOW PRESSURE EXTENDING FROM LAKE SUPERIOR TO THE OKLAHOMA PANHANDLE SHOULD BE JUST ABOUT THROUGH THE CWA WITH A WIND SHIFT FROM SOUTHWEST TO NORTHWEST. THE COOLER AIR WILL LAG BEHIND THE TROUGH A WAYS AND THURSDAY SHOULD BE QUITE NICE...JUST A FEW DEGREES LOWER THAN SEASONAL NORMALS. THE NEXT IN THE PROGRESSION OF MID LEVEL SHORTWAVES NOTED ABOVE IS THEN SLATED TO APPROACH THE PLAINS FROM THE NORTHWEST THURSDAY NIGHT INTO FRIDAY. SEVERAL MODELS SHOW A SIMILAR SOLUTION IN TAKING ONE WAVE NORTH AND EAST OF US AND DIGGING ANOTHER WAVE TO OUR WEST AND THEN SOUTH ACROSS KANSAS. INTERESTING TO RUN A TIME HEIGHT SECTION COMPARING THE GRAND ISLAND AREA TO THE PHILLIPSBURG KANSAS AREA IN TERMS OF MID LEVEL FORCING. THE NAM IS ONLY PRODUCING 1-2 UBARS PER SEC OF OMEGA OVER KGRI AT 12Z FRIDAY WHILE AT KPHG IT IS GENERATING 10-12 UBARS PER SEC. THE GFS HAS SIMILAR RESULTS FOR OUR SOUTHERN CWA WITH THE ONLY DIFFERENCE BEING THE GFS HAS A LITTLE LESS LOW LEVEL MOISTURE TO WORK WITH AND MAY TAKE A WHILE TO SATURATE THE COLUMN...WHILE THE NAM IS SATURATED ALL THE WAY FROM NEAR THE SURFACE TO 300 MB. THE EC FORECAST SOUNDING IS SIMILAR TO THE GFS AS IT IS NOT QUITE SATURATED UP TO 700MB. NEITHER THE GFS OR EC IS SHOWING THE LOWER PORTION BECOMING SATURATED BETWEEN 12 AND 18Z FRIDAY BUT I AM A LITTLE CONCERNED OF THE SCENARIO WHERE SNOW FALLING FROM ABOVE MOISTENS AND COOLS THE LOWER COLUMN UNTIL IT REACHES SATURATION. IF THIS WERE TO OCCUR...WE COULD SEE A LITTLE SNOW FRIDAY MORNING IN THE CWA. WILL NOT INCLUDE SNOW IN THE GRIDS FOR NOW AS I ONLY HAVE LOW TEMPERATURES FRIDAY MORNING FORECASTED TO BE AROUND 37 OR 38 DEGREES IN THE KANSAS PART OF OUR CWA...BUT IT WILL BE WORTH KEEPING AN EYE ON THE NEXT COUPLE OF DAYS. BUMPED UP POPS IN THE SOUTHERN PART OF THE CWA FOR FRIDAY AND THESE WILL NEED TO BE RAISED EVEN MORE IF THE MODELS REMAIN CONSISTENT ON THE TRACK OF THE SHORT WAVE TROUGH. THE COOLER AIR WILL THEN MAKE IT INTO THE AREA THURSDAY NIGHT AND BY FRIDAY HIGHS SHOULD BE 5 TO 10 DEGREES COOLER THAN ON THURSDAY. BUT THE COOLER WEATHER WILL ONLY LAST A DAY AS SATURDAY THROUGH TUESDAY SHOULD AGAIN BE IN THE UPPER 50S NORTH TO THE MID 60S SOUTH. WILL LEAVE REST OF FORECAST DRY FOR NOW BUT NOT TOTALLY OUT OF THE QUESTION THAT ONE OR TWO DISTURBANCES RIDING DOWN THE NORTHWEST FLOW MAY GIVE US AT LEAST A SLIGHT CHANCE FOR ADDITIONAL PRECIPITATION. && .AVIATION...(FOR THE 12Z KGRI TAF THROUGH 12Z THURSDAY MORNING) ISSUED AT 550 AM CDT WED OCT 16 2013 COMPARED TO THE PAST FEW DAYS...THE UPCOMING PERIOD WILL BE MARKED BY MUCH MORE TRANQUIL AVIATION WEATHER IN SOUTH CENTRAL NEBRASKA. DESPITE PASSING BATCHES OF MID LEVEL CLOUDS CENTERED NEAR/ABOVE 9000 FT...THERE IS HIGH CONFIDENCE IN VFR CONDITIONS THROUGHOUT...AND ESSENTIALLY ZERO RISK OF PRECIPITATION. AS FOR SURFACE WINDS...SPEEDS WILL AVERAGE AT/BELOW 11KT FROM THE WEST- NORTHWEST TODAY BEFORE BECOMING LIGHTER AND SOMEWHAT VARIABLE IN DIRECTION THIS EVENING/TONIGHT...WITH THE ADVERTISED DIRECTION OF 240 DEGREES AFTER 00Z REPRESENTING AN AVERAGE DIRECTION FOR THE NIGHT. && .GID WATCHES/WARNINGS/ADVISORIES... NE...FROST ADVISORY UNTIL 9 AM CDT THIS MORNING FOR NEZ062>064- 075>077-085>087. FREEZE WARNING UNTIL 9 AM CDT THIS MORNING FOR NEZ060-061- 072>074-082>084. KS...FROST ADVISORY UNTIL 9 AM CDT THIS MORNING FOR KSZ007-019. FREEZE WARNING UNTIL 9 AM CDT THIS MORNING FOR KSZ005-006-017- 018. && $$ UPDATE...PFANNKUCH SHORT TERM...PFANNKUCH LONG TERM...EWALD AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS HASTINGS NE
550 AM CDT WED OCT 16 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 430 AM CDT WED OCT 16 2013 COMPARED TO THE PAST 48 HOURS OF WIDESPREAD RAIN FOLLOWED BY FAIRLY STRONG NORTHWEST WINDS...THESE NEXT 24 HOURS ARE GOING TO BE A BENIGN CHANGE OF PACE...WITH ESSENTIALLY ZERO RISK OF MEASURABLE PRECIP AND SUSTAINED BREEZES STRUGGLING TO EXCEED 12 MPH AT MOST. HOWEVER...DUE TO FROST/FREEZE SENSITIVITIES THIS TIME OF YEAR...SKY COVER/CLOUD TRENDS HAVE TAKEN ON AN ENHANCED FORECAST FOCUS...GIVEN THE PRONOUNCED EFFECT OF CLOUD COVER ON TEMPERATURES. AS IT IS TURNING OUT...PARTS OF THE CWA ARE GOING TO FREEZE AND/OR FROST FAIRLY EFFICIENTLY THIS MORNING...WHILE OTHER PARTS OF THE AREA MAY ACTUALLY SEE MORE FAVORABLE CONDITIONS FOR FROST/FREEZE WEDNESDAY NIGHT INSTEAD. 07Z OBJECTIVE SURFACE ANALYSIS SHOWS THE LOCAL AREA POSITIONED BETWEEN A 1003 MILLIBAR LOW THAT HAS DEPARTED WELL EASTWARD INTO THE GREAT LAKES...AND A 1025 MILLIBAR HIGH CENTERED MUCH CLOSER TO HOME OVER THE NEB/KS/CO BORDER AREA. WITH THE PRESSURE GRADIENT CONTINUING TO RELAX...WEST-NORTHWEST BREEZES ACROSS MOST OF THIS CWA HAVE FINALLY EASED TO 10 MPH OR LESS...BUT WITH SLIGHTLY STRONGER SPEEDS STILL SHOWING UP NOW AND THEN MAINLY IN THE NORTHEAST. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA REVEAL THAT THE CWA IS POSITIONED ALMOST DIRECTLY UNDERNEATH A BROAD...SEVERELY POSITIVELY TILTED MID/UPPER LEVEL TROUGH AXIS EXTENDING IN A SOUTHWEST-NORTHEAST ORIENTATION FROM THE 4-CORNERS AREA THROUGH THE GREAT LAKES AND UP INTO EASTERN CANADA. ALONG THE SOUTHERN EDGE OF THIS TROUGH AXIS...A 105+ KT JET STREAK IS EVIDENT AT 300MB OVER THE KS/NEB BORDER. THE FOLLOWING PARAGRAPH FOCUSES SOLELY ON EXISTING FROST/FREEZE HEADLINES THIS MORNING...THE REAL HEADACHE THIS MORNING LIES WITH CLOUD COVER TRENDS PER IR AND 11-3.9 MICRON SATELLITE. ON A POSITIVE NOTE FOR CURRENT FROST/FREEZE HEADLINES...THE EXPANSIVE DECK OF LOW STRATUS THAT RULED MOST OF THE CWA ON TUESDAY CONTINUES TO STEADILY ERODE FROM NORTHWEST-TO-SOUTHEAST...WHICH MAKES IT NOW LOOK LIKE MUCH OF THE CWA SHOULD SEE AT LEAST A FEW HOURS OF CLEAR SKIES...POTENTIALLY ALLOWING FROST FORMATION TO COMMENCE. IN FACT...THIS PROCESS IS LIKELY ALREADY WELL-UNDERWAY IN/NEAR FAR WESTERN PORTIONS OF THE CWA...WHERE SITES SUCH AS LEXINGTON/MCCOOK HAVE ALREADY TUMBLED INTO THE LOW 30S THUS VERIFYING THE EXISTING FREEZE WARNING. HOWEVER...ON THE FLIP SIDE...PORTIONS OF THE ORIGINAL FROST ADVISORY ACROSS ROUGHLY THE EASTERN HALF OF THE CWA SEEMS TO BE FACING A GREATER OBSTACLE TO VERIFY...AS FOLLOWING SHORTLY BEHIND THE VACATING LOW STRATUS IS A SOUTHWARD-SINKING BAND OF MID LEVEL CLOUDS CENTERED BETWEEN 8-10K FEET...WHICH HAS ALREADY BRUSHED INTO THE FAR NORTHERN CWA...AND IS EXPECTED TO SLOWLY DROP SOUTHWARD TO AT LEAST ROUGHLY THE HIGHWAY 6 CORRIDOR BY SUNRISE. HOWEVER...THESE MID CLOUDS SHOULD HAVE LITTLE EFFECT ON EARLY MORNING TEMPERATURES ACROSS MOST OF THE SOUTHERN HALF TO ONE-THIRD OF THE CWA...WITH THESE AREAS LIKELY HEADED FOR SEVERAL HOURS OF CLEARING IN THE WAKE OF THE DEPARTING LOWER DECK. THE NET RESULT...AS IT CURRENTLY STANDS AT 09Z/4AM...IS THAT ADVISORIES/WARNINGS WERE CANCELLED FOR 5 COUNTIES NORTH OF INTERSTATE 80...WHILE AT LEAST FOR NOW WILL LET THE REMAINING 23 COUNTIES STAND AS-IS PER ORIGINAL ISSUANCE...AND TAKE ANOTHER LOOK FOR POSSIBLE UPDATES IN A FEW HOURS. TURNING TO OTHER ELEMENTS OF THE FORECAST...RIGHT OFF THE BAT DECIDED TO SLIP A SLIGHT CHANCE OF SPRINKLES INTO FAR NORTHERN AREAS UP AROUND ORD/GREELEY PRIOR TO SUNRISE TO ACCOUNT FOR A FEW WEAK RETURNS SHOWING UP ON RADAR UNDER THE INVADING MID-DECK...BUT THIS SHOULD BE VERY ISOLATED IN NATURE. BEYOND SUNRISE...ANTICIPATE A COOLISH BUT SEASONABLY PLEASANT DAY UNDER VARIABLE CLOUD COVER. ALOFT...THE AFOREMENTIONED ELONGATED MID LEVEL TROUGH AXIS WILL CONTINUE SLIPPING SOUTHWARD ACROSS THE REGION...AS A SHORTWAVE CURRENTLY WITHIN THE BASE OF THE TROUGH NEAR THE 4-CORNERS AREA GRADUALLY EJECTS EASTWARD ALONG THE KS/OK BORDER AS THE DAY WEARS ON. WHILE ANY SPOTTY RAIN FROM THIS DISTURBANCE SHOULD REMAIN WELL SOUTH OF THE LOCAL AREA...ESPECIALLY OUR KS ZONES COULD SEE A FAIR AMOUNT OF MID/UPPER LEVEL CLOUDS STREAMING EAST-NORTHEAST FROM THIS SYSTEM. MEANWHILE...THE ALREADY-PRESENT MID DECK SLIPPING INTO NORTHERN COUNTIES WILL CONTINUE TO SLOWLY SINK SOUTHWARD...AND IS EXPECTED TO PROVIDE A CLOUDY START TO THE DAY ACROSS THE MAJORITY OF NEB ZONES...BUT THEN ACCORDING TO 700 MILLIBAR RELATIVE HUMIDITY PROGS FROM THE RAP/NAM...SHOULD GRADUALLY FADE AWAY OR SCATTER OUT BY THE MID-LATE MORNING HOURS. SO...THE NET RESULT IS BEST PUT AS VARIABLE CLOUD COVER...AS NORTHERN AREAS SHOULD GENERALLY START OUT RATHER CLOUDY BUT SEE INCREASING SUN WITH TIME...WHILE SOUTHERN AREAS GENERALLY DO THE OPPOSITE AND SEE INCREASING CLOUDS WITH TIME. THESE CLOUD COVER TRENDS WILL BE TOUGH TO CAPTURE IN HOURLY FORECAST GRIDS...AND PLENTY OF UPDATES ARE LIKELY. OTHERWISE...AS THE CENTER OF THE SURFACE RIDGE AXIS SINKS SOUTH OF THE AREA TODAY...BREEZES WILL AVERAGE 10-12 MPH FROM THE WEST-NORTHWEST IN ALL AREAS. HIGH TEMPERATURES WERE ONLY TWEAKED SLIGHTLY PER A BLEND OF MET/MAV GUIDANCE AND RAP TEMPS...AND THUS WILL CONTINUE TO CALL FOR A REMARKABLY UNIFORM RANGE ACROSS THE CWA WITH ALL AREAS TOPPING OUT BETWEEN 56-59. FOR THIS EVENING/TONIGHT...THE MAIN STORY ALOFT IS THAT THE CURRENT SOUTHWEST-TO-NORTHEAST TROUGH AXIS WILL GRADUALLY BE REPLACED BY A SOUTHWEST-NORTHEAST ORIENTED SHORTWAVE RIDGE AXIS. THIS IS BECAUSE THE LOCAL AREA WILL BE IN BETWEEN TROUGHS...AS THE DISTURBANCE CENTERED OVER SOUTHERN KS AT SUNSET DEPARTS EASTWARD INTO MO...WHILE THE NEXT UPSTREAM TROUGH DROPPING SOUTHEAST TOWARD THE AREA ONLY REACHES AN AXIS FROM NORTHWEST CO TO NORTH DAKOTA BY SUNRISE THURSDAY. ALTHOUGH AM EXPECTING SKIES WEDNESDAY NIGHT AS A WHOLE TO AVERAGE CLEARER THAN THIS ONGOING NIGHT HAS BEEN...THERE IS AGAIN GOING TO BE VARIABLE CLOUD COVER EXCEPT THIS TIME SOLELY OF THE MID-UPPER VARIETY. FOR ONE...MAINLY SOUTHERN PARTS OF THE CWA WILL LIKELY START THE EVENING WITH LINGERING CLOUDS FROM THE DEPARTING DISTURBANCE...WHILE LATER IN THE NIGHT...MAINLY NORTHERN AREAS COULD SEE PASSING BATCHES OF CLOUDS OUT AHEAD OF THE APPROACHING UPSTREAM WAVE. MEANWHILE AT THE SURFACE...WINDS WILL REMAIN FAIRLY LIGHT AT SUSTAINED SPEEDS GENERALLY LESS THAN 8 MPH...BUT GRADUALLY TRANSITION FROM A SOUTHWESTERLY DIRECTION TO NORTHWESTERLY IN RESPONSE TO A SUBTLE PASSING TROUGH AXIS. AS FOR LOW TEMPS...ONCE AGAIN PASSING CLOUDS COULD POSE ISSUES...BUT FOR NOW STUCK VERY CLOSE TO A MET/MAV GUIDANCE BLEND...WHICH PUTS THE MAJORITY OF THE CWA DOWN BETWEEN 33-36 DEGREES...WITH THE TYPICALLY FAVORED DAWSON-TO-VALLEY COUNTY CORRIDOR MOST FAVORED TO SLIP SLIGHTLY BELOW FREEZING. OBVIOUSLY THESE LOWS ARE AGAIN SUPPORTIVE OF FROST AND/OR FREEZE DEVELOPMENT. HOWEVER...GIVEN THE ONGOING COMPLICATIONS/UNCERTAINTY THIS MORNING REGARDING LOW TEMPS...WILL HOLD OFF ON ANY WEDNESDAY NIGHT FROST ADVISORIES/FREEZE WARNINGS FOR NOW...NOT ONLY TO AVOID HEADLINE CONFUSION...BUT ALSO TO ALLOW DAY SHIFT TO IDENTIFY COUNTIES THAT COULD NOW BE RULED INELIGIBLE FROM FUTURE FROST/FREEZE HEADLINES BASED ON WHAT HAPPENS THIS MORNING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 430 AM CDT WED OCT 16 2013 MAIN CONCERNS THIS FORECAST PERIOD LOOKS TO BE PRECIPITATION CHANCES ON FRIDAY. STARTING OUT THURSDAY MORNING WITH THE BIG PICTURE...THERE SHOULD BE A HIGH AMPLITUDE RIDGE JUST OFF THE PACIFIC U.S. AND CANADIAN COAST WITH A LONG WAVE TROUGH AND SEVERAL EMBEDDED SHORT WAVES SITUATED OVER MUCH OF THE CONUS. THIS PATTERN WILL GRADUALLY SHIFT EAST A BIT BUT THE CENTRAL PLAINS SHOULD STILL BE SITTING ON THE BACK SIDE OF THE UPPER TROUGH BY NEXT TUESDAY...PUTTING US IN NORTHWEST FLOW. AT THE SURFACE ON TUESDAY MORNING...A TROUGH OF LOW PRESSURE EXTENDING FROM LAKE SUPERIOR TO THE OKLAHOMA PANHANDLE SHOULD BE JUST ABOUT THROUGH THE CWA WITH A WIND SHIFT FROM SOUTHWEST TO NORTHWEST. THE COOLER AIR WILL LAG BEHIND THE TROUGH A WAYS AND THURSDAY SHOULD BE QUITE NICE...JUST A FEW DEGREES LOWER THAN SEASONAL NORMALS. THE NEXT IN THE PROGRESSION OF MID LEVEL SHORTWAVES NOTED ABOVE IS THEN SLATED TO APPROACH THE PLAINS FROM THE NORTHWEST THURSDAY NIGHT INTO FRIDAY. SEVERAL MODELS SHOW A SIMILAR SOLUTION IN TAKING ONE WAVE NORTH AND EAST OF US AND DIGGING ANOTHER WAVE TO OUR WEST AND THEN SOUTH ACROSS KANSAS. INTERESTING TO RUN A TIME HEIGHT SECTION COMPARING THE GRAND ISLAND AREA TO THE PHILLIPSBURG KANSAS AREA IN TERMS OF MID LEVEL FORCING. THE NAM IS ONLY PRODUCING 1-2 UBARS PER SEC OF OMEGA OVER KGRI AT 12Z FRIDAY WHILE AT KPHG IT IS GENERATING 10-12 UBARS PER SEC. THE GFS HAS SIMILAR RESULTS FOR OUR SOUTHERN CWA WITH THE ONLY DIFFERENCE BEING THE GFS HAS A LITTLE LESS LOW LEVEL MOISTURE TO WORK WITH AND MAY TAKE A WHILE TO SATURATE THE COLUMN...WHILE THE NAM IS SATURATED ALL THE WAY FROM NEAR THE SURFACE TO 300 MB. THE EC FORECAST SOUNDING IS SIMILAR TO THE GFS AS IT IS NOT QUITE SATURATED UP TO 700MB. NEITHER THE GFS OR EC IS SHOWING THE LOWER PORTION BECOMING SATURATED BETWEEN 12 AND 18Z FRIDAY BUT I AM A LITTLE CONCERNED OF THE SCENARIO WHERE SNOW FALLING FROM ABOVE MOISTENS AND COOLS THE LOWER COLUMN UNTIL IT REACHES SATURATION. IF THIS WERE TO OCCUR...WE COULD SEE A LITTLE SNOW FRIDAY MORNING IN THE CWA. WILL NOT INCLUDE SNOW IN THE GRIDS FOR NOW AS I ONLY HAVE LOW TEMPERATURES FRIDAY MORNING FORECASTED TO BE AROUND 37 OR 38 DEGREES IN THE KANSAS PART OF OUR CWA...BUT IT WILL BE WORTH KEEPING AN EYE ON THE NEXT COUPLE OF DAYS. BUMPED UP POPS IN THE SOUTHERN PART OF THE CWA FOR FRIDAY AND THESE WILL NEED TO BE RAISED EVEN MORE IF THE MODELS REMAIN CONSISTENT ON THE TRACK OF THE SHORT WAVE TROUGH. THE COOLER AIR WILL THEN MAKE IT INTO THE AREA THURSDAY NIGHT AND BY FRIDAY HIGHS SHOULD BE 5 TO 10 DEGREES COOLER THAN ON THURSDAY. BUT THE COOLER WEATHER WILL ONLY LAST A DAY AS SATURDAY THROUGH TUESDAY SHOULD AGAIN BE IN THE UPPER 50S NORTH TO THE MID 60S SOUTH. WILL LEAVE REST OF FORECAST DRY FOR NOW BUT NOT TOTALLY OUT OF THE QUESTION THAT ONE OR TWO DISTURBANCES RIDING DOWN THE NORTHWEST FLOW MAY GIVE US AT LEAST A SLIGHT CHANCE FOR ADDITIONAL PRECIPITATION. && .AVIATION...(FOR THE 12Z KGRI TAF THROUGH 12Z THURSDAY MORNING) ISSUED AT 550 AM CDT WED OCT 16 2013 COMPARED TO THE PAST FEW DAYS...THE UPCOMING PERIOD WILL BE MARKED BY MUCH MORE TRANQUIL AVIATION WEATHER IN SOUTH CENTRAL NEBRASKA. DESPITE PASSING BATCHES OF MID LEVEL CLOUDS CENTERED NEAR/ABOVE 9000 FT...THERE IS HIGH CONFIDENCE IN VFR CONDITIONS THROUGHOUT...AND ESSENTIALLY ZERO RISK OF PRECIPITATION. AS FOR SURFACE WINDS...SPEEDS WILL AVERAGE AT/BELOW 11KT FROM THE WEST- NORTHWEST TODAY BEFORE BECOMING LIGHTER AND SOMEWHAT VARIABLE IN DIRECTION THIS EVENING/TONIGHT...WITH THE ADVERTISED DIRECTION OF 240 DEGREES AFTER 00Z REPRESENTING AN AVERAGE DIRECTION FOR THE NIGHT. && .GID WATCHES/WARNINGS/ADVISORIES... NE...FROST ADVISORY UNTIL 9 AM CDT THIS MORNING FOR NEZ062>064- 075>077-085>087. FREEZE WARNING UNTIL 9 AM CDT THIS MORNING FOR NEZ060-061- 072>074-082>084. KS...FROST ADVISORY UNTIL 9 AM CDT THIS MORNING FOR KSZ007-019. FREEZE WARNING UNTIL 9 AM CDT THIS MORNING FOR KSZ005-006-017- 018. && $$ SHORT TERM...PFANNKUCH LONG TERM...EWALD AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS HASTINGS NE
431 AM CDT WED OCT 16 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 430 AM CDT WED OCT 16 2013 COMPARED TO THE PAST 48 HOURS OF WIDESPREAD RAIN FOLLOWED BY FAIRLY STRONG NORTHWEST WINDS...THESE NEXT 24 HOURS ARE GOING TO BE A BENIGN CHANGE OF PACE...WITH ESSENTIALLY ZERO RISK OF MEASURABLE PRECIP AND SUSTAINED BREEZES STRUGGLING TO EXCEED 12 MPH AT MOST. HOWEVER...DUE TO FROST/FREEZE SENSITIVITIES THIS TIME OF YEAR...SKY COVER/CLOUD TRENDS HAVE TAKEN ON AN ENHANCED FORECAST FOCUS...GIVEN THE PRONOUNCED EFFECT OF CLOUD COVER ON TEMPERATURES. AS IT IS TURNING OUT...PARTS OF THE CWA ARE GOING TO FREEZE AND/OR FROST FAIRLY EFFICIENTLY THIS MORNING...WHILE OTHER PARTS OF THE AREA MAY ACTUALLY SEE MORE FAVORABLE CONDITIONS FOR FROST/FREEZE WEDNESDAY NIGHT INSTEAD. 07Z OBJECTIVE SURFACE ANALYSIS SHOWS THE LOCAL AREA POSITIONED BETWEEN A 1003 MILLIBAR LOW THAT HAS DEPARTED WELL EASTWARD INTO THE GREAT LAKES...AND A 1025 MILLIBAR HIGH CENTERED MUCH CLOSER TO HOME OVER THE NEB/KS/CO BORDER AREA. WITH THE PRESSURE GRADIENT CONTINUING TO RELAX...WEST-NORTHWEST BREEZES ACROSS MOST OF THIS CWA HAVE FINALLY EASED TO 10 MPH OR LESS...BUT WITH SLIGHTLY STRONGER SPEEDS STILL SHOWING UP NOW AND THEN MAINLY IN THE NORTHEAST. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA REVEAL THAT THE CWA IS POSITIONED ALMOST DIRECTLY UNDERNEATH A BROAD...SEVERELY POSITIVELY TILTED MID/UPPER LEVEL TROUGH AXIS EXTENDING IN A SOUTHWEST-NORTHEAST ORIENTATION FROM THE 4-CORNERS AREA THROUGH THE GREAT LAKES AND UP INTO EASTERN CANADA. ALONG THE SOUTHERN EDGE OF THIS TROUGH AXIS...A 105+ KT JET STREAK IS EVIDENT AT 300MB OVER THE KS/NEB BORDER. THE FOLLOWING PARAGRAPH FOCUSES SOLELY ON EXISTING FROST/FREEZE HEADLINES THIS MORNING...THE REAL HEADACHE THIS MORNING LIES WITH CLOUD COVER TRENDS PER IR AND 11-3.9 MICRON SATELLITE. ON A POSITIVE NOTE FOR CURRENT FROST/FREEZE HEADLINES...THE EXPANSIVE DECK OF LOW STRATUS THAT RULED MOST OF THE CWA ON TUESDAY CONTINUES TO STEADILY ERODE FROM NORTHWEST-TO-SOUTHEAST...WHICH MAKES IT NOW LOOK LIKE MUCH OF THE CWA SHOULD SEE AT LEAST A FEW HOURS OF CLEAR SKIES...POTENTIALLY ALLOWING FROST FORMATION TO COMMENCE. IN FACT...THIS PROCESS IS LIKELY ALREADY WELL-UNDERWAY IN/NEAR FAR WESTERN PORTIONS OF THE CWA...WHERE SITES SUCH AS LEXINGTON/MCCOOK HAVE ALREADY TUMBLED INTO THE LOW 30S THUS VERIFYING THE EXISTING FREEZE WARNING. HOWEVER...ON THE FLIP SIDE...PORTIONS OF THE ORIGINAL FROST ADVISORY ACROSS ROUGHLY THE EASTERN HALF OF THE CWA SEEMS TO BE FACING A GREATER OBSTACLE TO VERIFY...AS FOLLOWING SHORTLY BEHIND THE VACATING LOW STRATUS IS A SOUTHWARD-SINKING BAND OF MID LEVEL CLOUDS CENTERED BETWEEN 8-10K FEET...WHICH HAS ALREADY BRUSHED INTO THE FAR NORTHERN CWA...AND IS EXPECTED TO SLOWLY DROP SOUTHWARD TO AT LEAST ROUGHLY THE HIGHWAY 6 CORRIDOR BY SUNRISE. HOWEVER...THESE MID CLOUDS SHOULD HAVE LITTLE EFFECT ON EARLY MORNING TEMPERATURES ACROSS MOST OF THE SOUTHERN HALF TO ONE-THIRD OF THE CWA...WITH THESE AREAS LIKELY HEADED FOR SEVERAL HOURS OF CLEARING IN THE WAKE OF THE DEPARTING LOWER DECK. THE NET RESULT...AS IT CURRENTLY STANDS AT 09Z/4AM...IS THAT ADVISORIES/WARNINGS WERE CANCELLED FOR 5 COUNTIES NORTH OF INTERSTATE 80...WHILE AT LEAST FOR NOW WILL LET THE REMAINING 23 COUNTIES STAND AS-IS PER ORIGINAL ISSUANCE...AND TAKE ANOTHER LOOK FOR POSSIBLE UPDATES IN A FEW HOURS. TURNING TO OTHER ELEMENTS OF THE FORECAST...RIGHT OFF THE BAT DECIDED TO SLIP A SLIGHT CHANCE OF SPRINKLES INTO FAR NORTHERN AREAS UP AROUND ORD/GREELEY PRIOR TO SUNRISE TO ACCOUNT FOR A FEW WEAK RETURNS SHOWING UP ON RADAR UNDER THE INVADING MID-DECK...BUT THIS SHOULD BE VERY ISOLATED IN NATURE. BEYOND SUNRISE...ANTICIPATE A COOLISH BUT SEASONABLY PLEASANT DAY UNDER VARIABLE CLOUD COVER. ALOFT...THE AFOREMENTIONED ELONGATED MID LEVEL TROUGH AXIS WILL CONTINUE SLIPPING SOUTHWARD ACROSS THE REGION...AS A SHORTWAVE CURRENTLY WITHIN THE BASE OF THE TROUGH NEAR THE 4-CORNERS AREA GRADUALLY EJECTS EASTWARD ALONG THE KS/OK BORDER AS THE DAY WEARS ON. WHILE ANY SPOTTY RAIN FROM THIS DISTURBANCE SHOULD REMAIN WELL SOUTH OF THE LOCAL AREA...ESPECIALLY OUR KS ZONES COULD SEE A FAIR AMOUNT OF MID/UPPER LEVEL CLOUDS STREAMING EAST-NORTHEAST FROM THIS SYSTEM. MEANWHILE...THE ALREADY-PRESENT MID DECK SLIPPING INTO NORTHERN COUNTIES WILL CONTINUE TO SLOWLY SINK SOUTHWARD...AND IS EXPECTED TO PROVIDE A CLOUDY START TO THE DAY ACROSS THE MAJORITY OF NEB ZONES...BUT THEN ACCORDING TO 700 MILLIBAR RELATIVE HUMIDITY PROGS FROM THE RAP/NAM...SHOULD GRADUALLY FADE AWAY OR SCATTER OUT BY THE MID-LATE MORNING HOURS. SO...THE NET RESULT IS BEST PUT AS VARIABLE CLOUD COVER...AS NORTHERN AREAS SHOULD GENERALLY START OUT RATHER CLOUDY BUT SEE INCREASING SUN WITH TIME...WHILE SOUTHERN AREAS GENERALLY DO THE OPPOSITE AND SEE INCREASING CLOUDS WITH TIME. THESE CLOUD COVER TRENDS WILL BE TOUGH TO CAPTURE IN HOURLY FORECAST GRIDS...AND PLENTY OF UPDATES ARE LIKELY. OTHERWISE...AS THE CENTER OF THE SURFACE RIDGE AXIS SINKS SOUTH OF THE AREA TODAY...BREEZES WILL AVERAGE 10-12 MPH FROM THE WEST-NORTHWEST IN ALL AREAS. HIGH TEMPERATURES WERE ONLY TWEAKED SLIGHTLY PER A BLEND OF MET/MAV GUIDANCE AND RAP TEMPS...AND THUS WILL CONTINUE TO CALL FOR A REMARKABLY UNIFORM RANGE ACROSS THE CWA WITH ALL AREAS TOPPING OUT BETWEEN 56-59. FOR THIS EVENING/TONIGHT...THE MAIN STORY ALOFT IS THAT THE CURRENT SOUTHWEST-TO-NORTHEAST TROUGH AXIS WILL GRADUALLY BE REPLACED BY A SOUTHWEST-NORTHEAST ORIENTED SHORTWAVE RIDGE AXIS. THIS IS BECAUSE THE LOCAL AREA WILL BE IN BETWEEN TROUGHS...AS THE DISTURBANCE CENTERED OVER SOUTHERN KS AT SUNSET DEPARTS EASTWARD INTO MO...WHILE THE NEXT UPSTREAM TROUGH DROPPING SOUTHEAST TOWARD THE AREA ONLY REACHES AN AXIS FROM NORTHWEST CO TO NORTH DAKOTA BY SUNRISE THURSDAY. ALTHOUGH AM EXPECTING SKIES WEDNESDAY NIGHT AS A WHOLE TO AVERAGE CLEARER THAN THIS ONGOING NIGHT HAS BEEN...THERE IS AGAIN GOING TO BE VARIABLE CLOUD COVER EXCEPT THIS TIME SOLELY OF THE MID-UPPER VARIETY. FOR ONE...MAINLY SOUTHERN PARTS OF THE CWA WILL LIKELY START THE EVENING WITH LINGERING CLOUDS FROM THE DEPARTING DISTURBANCE...WHILE LATER IN THE NIGHT...MAINLY NORTHERN AREAS COULD SEE PASSING BATCHES OF CLOUDS OUT AHEAD OF THE APPROACHING UPSTREAM WAVE. MEANWHILE AT THE SURFACE...WINDS WILL REMAIN FAIRLY LIGHT AT SUSTAINED SPEEDS GENERALLY LESS THAN 8 MPH...BUT GRADUALLY TRANSITION FROM A SOUTHWESTERLY DIRECTION TO NORTHWESTERLY IN RESPONSE TO A SUBTLE PASSING TROUGH AXIS. AS FOR LOW TEMPS...ONCE AGAIN PASSING CLOUDS COULD POSE ISSUES...BUT FOR NOW STUCK VERY CLOSE TO A MET/MAV GUIDANCE BLEND...WHICH PUTS THE MAJORITY OF THE CWA DOWN BETWEEN 33-36 DEGREES...WITH THE TYPICALLY FAVORED DAWSON-TO-VALLEY COUNTY CORRIDOR MOST FAVORED TO SLIP SLIGHTLY BELOW FREEZING. OBVIOUSLY THESE LOWS ARE AGAIN SUPPORTIVE OF FROST AND/OR FREEZE DEVELOPMENT. HOWEVER...GIVEN THE ONGOING COMPLICATIONS/UNCERTAINTY THIS MORNING REGARDING LOW TEMPS...WILL HOLD OFF ON ANY WEDNESDAY NIGHT FROST ADVISORIES/FREEZE WARNINGS FOR NOW...NOT ONLY TO AVOID HEADLINE CONFUSION...BUT ALSO TO ALLOW DAY SHIFT TO IDENTIFY COUNTIES THAT COULD NOW BE RULED INELIGIBLE FROM FUTURE FROST/FREEZE HEADLINES BASED ON WHAT HAPPENS THIS MORNING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 430 AM CDT WED OCT 16 2013 MAIN CONCERNS THIS FORECAST PERIOD LOOKS TO BE PRECIPITATION CHANCES ON FRIDAY. STARTING OUT THURSDAY MORNING WITH THE BIG PICTURE...THERE SHOULD BE A HIGH AMPLITUDE RIDGE JUST OFF THE PACIFIC U.S. AND CANADIAN COAST WITH A LONG WAVE TROUGH AND SEVERAL EMBEDDED SHORT WAVES SITUATED OVER MUCH OF THE CONUS. THIS PATTERN WILL GRADUALLY SHIFT EAST A BIT BUT THE CENTRAL PLAINS SHOULD STILL BE SITTING ON THE BACK SIDE OF THE UPPER TROUGH BY NEXT TUESDAY...PUTTING US IN NORTHWEST FLOW. AT THE SURFACE ON TUESDAY MORNING...A TROUGH OF LOW PRESSURE EXTENDING FROM LAKE SUPERIOR TO THE OKLAHOMA PANHANDLE SHOULD BE JUST ABOUT THROUGH THE CWA WITH A WIND SHIFT FROM SOUTHWEST TO NORTHWEST. THE COOLER AIR WILL LAG BEHIND THE TROUGH A WAYS AND THURSDAY SHOULD BE QUITE NICE...JUST A FEW DEGREES LOWER THAN SEASONAL NORMALS. THE NEXT IN THE PROGRESSION OF MID LEVEL SHORTWAVES NOTED ABOVE IS THEN SLATED TO APPROACH THE PLAINS FROM THE NORTHWEST THURSDAY NIGHT INTO FRIDAY. SEVERAL MODELS SHOW A SIMILAR SOLUTION IN TAKING ONE WAVE NORTH AND EAST OF US AND DIGGING ANOTHER WAVE TO OUR WEST AND THEN SOUTH ACROSS KANSAS. INTERESTING TO RUN A TIME HEIGHT SECTION COMPARING THE GRAND ISLAND AREA TO THE PHILLIPSBURG KANSAS AREA IN TERMS OF MID LEVEL FORCING. THE NAM IS ONLY PRODUCING 1-2 UBARS PER SEC OF OMEGA OVER KGRI AT 12Z FRIDAY WHILE AT KPHG IT IS GENERATING 10-12 UBARS PER SEC. THE GFS HAS SIMILAR RESULTS FOR OUR SOUTHERN CWA WITH THE ONLY DIFFERENCE BEING THE GFS HAS A LITTLE LESS LOW LEVEL MOISTURE TO WORK WITH AND MAY TAKE A WHILE TO SATURATE THE COLUMN...WHILE THE NAM IS SATURATED ALL THE WAY FROM NEAR THE SURFACE TO 300 MB. THE EC FORECAST SOUNDING IS SIMILAR TO THE GFS AS IT IS NOT QUITE SATURATED UP TO 700MB. NEITHER THE GFS OR EC IS SHOWING THE LOWER PORTION BECOMING SATURATED BETWEEN 12 AND 18Z FRIDAY BUT I AM A LITTLE CONCERNED OF THE SCENARIO WHERE SNOW FALLING FROM ABOVE MOISTENS AND COOLS THE LOWER COLUMN UNTIL IT REACHES SATURATION. IF THIS WERE TO OCCUR...WE COULD SEE A LITTLE SNOW FRIDAY MORNING IN THE CWA. WILL NOT INCLUDE SNOW IN THE GRIDS FOR NOW AS I ONLY HAVE LOW TEMPERATURES FRIDAY MORNING FORECASTED TO BE AROUND 37 OR 38 DEGREES IN THE KANSAS PART OF OUR CWA...BUT IT WILL BE WORTH KEEPING AN EYE ON THE NEXT COUPLE OF DAYS. BUMPED UP POPS IN THE SOUTHERN PART OF THE CWA FOR FRIDAY AND THESE WILL NEED TO BE RAISED EVEN MORE IF THE MODELS REMAIN CONSISTENT ON THE TRACK OF THE SHORT WAVE TROUGH. THE COOLER AIR WILL THEN MAKE IT INTO THE AREA THURSDAY NIGHT AND BY FRIDAY HIGHS SHOULD BE 5 TO 10 DEGREES COOLER THAN ON THURSDAY. BUT THE COOLER WEATHER WILL ONLY LAST A DAY AS SATURDAY THROUGH TUESDAY SHOULD AGAIN BE IN THE UPPER 50S NORTH TO THE MID 60S SOUTH. WILL LEAVE REST OF FORECAST DRY FOR NOW BUT NOT TOTALLY OUT OF THE QUESTION THAT ONE OR TWO DISTURBANCES RIDING DOWN THE NORTHWEST FLOW MAY GIVE US AT LEAST A SLIGHT CHANCE FOR ADDITIONAL PRECIPITATION. && .AVIATION...(FOR THE 06Z KGRI TAF THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1234 AM CDT WED OCT 16 2013 COMPARED TO THE PAST 48 HOURS...THESE NEXT 24 HOURS WILL BE MARKED BY IMPROVING AVIATION WEATHER IN SOUTH CENTRAL NEBRASKA...WITH THE DEPARTURE OF MVFR CEILINGS AND CONTINUED SLACKENING OF WINDS. STARTING WITH CEILINGS...THE VAST MAJORITY OF THE PERIOD IS EXPECTED TO FEATURE VFR...DESPITE AT-TIMES CONSIDERABLE MID LEVEL CLOUDS WELL UP AROUND 9KT FEET. HOWEVER...STARTING OFF RIGHT AWAY EARLY THIS MORNING...IT APPEARS THAT THE LAST GASP OF THE CURRENT MVFR DECK WILL STILL HOLD ON FOR A FEW MORE HOURS BEFORE FINALLY ERODING OR EXITING TO THE SOUTH. WILL AIM FOR AN 08Z RETURN TO VFR...BUT ITS POSSIBLE THIS COULD BE A BIT OPTIMISTIC. AS FOR SURFACE WINDS...SPEEDS WILL AVERAGE AT/BELOW 11KT FROM THE WEST- NORTHWEST THROUGHOUT THE REST OF TONIGHT INTO THE DAY WEDNESDAY...BEFORE BECOMING LIGHT AND SOUTHWESTERLY WEDNESDAY EVENING. && .GID WATCHES/WARNINGS/ADVISORIES... NE...FROST ADVISORY UNTIL 9 AM CDT THIS MORNING FOR NEZ041-048-049- 062>064-075>077-085>087. FREEZE WARNING UNTIL 9 AM CDT THIS MORNING FOR NEZ046-047-060- 061-072>074-082>084. KS...FROST ADVISORY UNTIL 9 AM CDT THIS MORNING FOR KSZ007-019. FREEZE WARNING UNTIL 9 AM CDT THIS MORNING FOR KSZ005-006-017- 018. && $$ SHORT TERM...PFANNKUCH LONG TERM...EWALD AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
305 PM CDT WED OCT 16 2013 .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 305 PM CDT WED OCT 16 2013 MAIN FORECAST CHALLENGE THROUGH THE SHORT TERM WILL BE THE PERIODIC CHANCES FOR LIGHT RAIN POSSIBLY MIXED WITH A LITTLE WHITE STUFF. MODELS HAVE A DECENT HANDLE ON THINGS WHICH MATCHES UP WELL WITH FORECAST CONTINUITY. AS OF LATE AFTERNOON CLOUDS WERE SLOWLY STARTING TO INCREASE ACROSS THE NORTHWEST PART OF ND BUT NOT SO MUCH YET INTO THIS FA. TEMPS HAVE RISEN NICELY WITH THE WEST/SW WINDS CURRENTLY BEING REPORTED. THE COLD FRONT AND NORTHWEST WIND SWITCH ARE STARTING TO PUSH INTO NORTHWEST SECTIONS OF THE STATE. SO FAR NOT MUCH PCPN BEHIND THE UPSTREAM COLD FRONT AS JUST A FEW STATIONS IN NORTH CENTRAL MT ARE REPORTING LIGHT RAIN. HOWEVER THESE CLOUDS AND THE PATCHY LIGHT RAIN WILL SLOWLY MOVE IN TONIGHT AND MAINLY ALONG AND WEST OF THE RED RIVER VALLEY. TEMPS SHOULD STAY WARM ENOUGH TO KEEP ANY PCPN IN THE LIQUID FORM. FOR THU THE FIRST SHORT WAVE WILL FINISH MOVING THROUGH THE AREA MAINLY AFFECTING THE SOUTHERN HALF OF THE FA. THE NORTHWEST SHOULD SEE SOME CLEARING DURING THE AFTERNOON. MAY BE A BIT OF A BREAK IN THE PCPN THU EVENING BEFORE ANOTHER SHOT MOVES IN LATE. THIS TIME IT MAY BE COLD ENOUGH FOR THE RAIN TO MIX WITH A LITTLE SNOW LATE. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 305 PM CDT WED OCT 16 2 PRETTY SHARP NORTHWEST FLOW GETS ESTABLISHED BY FRI/SAT WITH THE ENDLESS PIECES OF ENERGY CONTINUING TO DROP SOUTHEAST IN IT. KEPT THE CHANCES FOR RAIN POSSIBLY MIXED WITH SNOW AT TIMES THROUGHOUT. SATURDAY NIGHT THROUGH WEDNESDAY...DETERMINISTIC MODELS ARE IN PRETTY GOOD AGREEMENT OVERALL ON A COLD AND FAIRLY WET PATTERN AS VARIOUS SHORTWAVES MOVE THROUGH THE NORTHWESTERLY FLOW ALOFT. THE DIFFERENCES ARE OF COURSE IN THE DETAILS OF THE EXACT TIMING OF THE SHORTWAVES. THINK THAT WITH SFC HIGH PRESSURE BUILDING IN SATURDAY NIGHT SHOULD BE FAIRLY QUIET...BUT THE MODELS ALL BRING IN ANOTHER SHORTWAVE WITH A CHANCE FOR PRECIP ON SUNDAY. AN EVEN STRONGER SHORTWAVE COMING DOWN INTO THE UPPER MIDWEST MONDAY WILL DRAG DOWN EVEN COOLER TEMPS FOR EARLY NEXT WEEK. THE 00Z ECMWF HAD THE HEIGHTS OVER THE REGION STARTING TO RISE AGAIN BY WEDNESDAY...BUT THE NEW 12Z RUN KEEPS THE MAIN TROUGH FURTHER WEST AND THE CWA IN THE COLDER AIR. WITH THE UNCERTAINTY OF THE SHORTWAVE TIMING...KEPT THE 20-30 POPS AS ALLBLEND GAVE US WITH SOME MINOR TWEAKS FOR AESTHETIC REASONS. SOME OF THE PRECIP DURING THE OVERNIGHT AND MORNING HOURS COULD BE SNOW...SO KEPT THE MIXED MENTION IN THE GRIDS. AFTERNOON TEMPS WILL BE WELL BELOW SEASONAL AVERAGES IN THE 40S...ALTHOUGH CLOUDS AT NIGHT WILL PREVENT LOWS FROM GETTING EXTREMELY COLD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1252 PM CDT WED OCT 16 2013 VFR CONDITIONS WILL CONTINUE THROUGH THE FIRST PART OF THE FORECAST PERIOD. WINDS WILL BECOME MORE WESTERLY BY LATE AFTERNOON OR EARLY EVENING ALONG WITH SOME MID LEVEL CLOUDS AS A TROUGH OF LOW PRESSURE MOVES INTO THE AREA. MORE SIGNIFICANT COLD AIR WILL NOT COME DOWN UNTIL LATER TONIGHT...WITH WINDS BECOMING NORTHWESTERLY OVERNIGHT. SOME OF THE MODELS SUCH AS THE HRRR AND THE SHORT RANGE ENSEMBLES SHOW MVFR OR EVEN IFR CIGS WITH THE BOUNDARY. COVERAGE OF THE REDUCED CATEGORIES LOOKS PRETTY SCATTERED HOWEVER. LOWERED CIGS A BIT BUT KEPT THINGS AT VFR EXCEPT FOR AT KDVL WHERE THEY HAVE A BETTER CHANCE OF GETTING BELOW 3000 FT. CONTINUED WITH VCSH...ALTHOUGH WITH LIMITED MOISTURE DO NOT THINK THE SHOWERS WILL BE MUCH MORE THAN SPRINKLES. ANY LOWER CIGS WILL DISSIPATE AFTER 16Z OR SO. && .HYDROLOGY... FLOOD WATCHES REMAIN IN EFFECT FOR THE RED RIVER AT FARGO AND MINNESOTA TRIBUTARIES AT DILWORTH AND SABIN. THESE POINTS ARE CURRENTLY EXHIBITING FLAT OR SLIGHTLY RISING BEHAVIOR AND IT IS UNCERTAIN WHETHER OR NOT ANY OR ALL OF THESE POINTS WILL REACH MINOR FLOOD. THE WATCHES WILL CONTINUE FOR THE TIME BEING. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...GODON LONG TERM...GODON/JR AVIATION...JR HYDROLOGY...WJB
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1252 PM CDT WED OCT 16 2013 .UPDATE... ISSUED AT 1252 PM CDT WED OCT 16 2013 FORECAST LOOKING ON TRACK AT THIS POINT SO NO UPDATES PLANNED. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 330 AM CDT WED OCT 16 2013 THE MAIN CHALLENGE WILL BE TEMPS AND LOW CHANCES FOR PRECIP. MODELS ARE IN GOOD OVERALL AGREEMENT WITH NO PREFERENCE THIS MORNING. FOR TODAY...EXPECT TEMPS TO WARM INTO THE MID 50S FOR THE ENTIRE REGION WITH PLENTIFUL SUNSHINE AND WESTERLY WINDS DEVELOPING. FOR TONIGHT...A SHORTWAVE AND SOME DEEPER MOISTURE WILL MOVE INTO THE WESTERN AREAS BY 6Z...THEN INTO THE SOUTH THEREAFTER. THERE COULD BE SOME RAIN SHOWERS MAINLY IN THE WEST LATER TONIGHT...BUT MOST AREAS WILL REMAIN DRY. ON THURSDAY...THERE COULD BE A FEW LINGERING SHOWERS IN THE SOUTH/SE...WITH CLEARING SKIES FROM NW TO SE BY AFTERNOON. TEMPS WILL BE COOLER THAN WED...WITH 850MB TEMPS FALLING BELOW 0C. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 330 AM CDT WED OCT 16 2013 FOR FRIDAY AND FRIDAY NIGHT...EXPECT COOL/CYCLONIC FLOW WITH CHANCES FOR SHOWERS. EXPECT SOME RAIN SHOWERS MIXING WITH SOME SNOW PERHAPS LATER FRIDAY NIGHT...AS A SECONDARY COLD FRONT DROPS SOUTH FROM CANADA AND SEVERAL SHORTWAVES MOVING THROUGH. FOR SATURDAY-TUESDAY...A RATHER STABLE LONGWAVE PATTERN OVER NORTH AMERICA WILL CONTINUE THROUGH THESE PERIODS...WITH A TROUGH OVER THE CENTRAL AND EASTERN CONUS...AND A SLOWLY PROGRESSING UPPER RIDGE FROM THE EASTERN PACIFIC INTO THE WESTERN CONUS. THIS WILL KEEP THE AREA UNDER NORTHWEST FLOW ALOFT. SEVERAL UPPER LEVEL SHORTWAVE TROUGHS WILL DIVE SOUTHEAST INTO THE NORTHERN PLAINS...BRINGING A FEW OPPORTUNITIES FOR LIGHT RAIN AND PERHAPS LIGHT SNOW DURING COOLER PERIODS...ALTHOUGH MODELS DIFFER ON THE EXACT TIMING AND PLACEMENT OF THE WAVES. TEMPS WILL BE ON THE COOL SIDE GIVEN THIS PATTERN...WITH HIGHS MAINLY IN THE 40S. QUITE A BIT OF CLOUD COVER IS EXPECTED...WHICH WILL LIKELY AFFECT OVERNIGHT LOWS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1252 PM CDT WED OCT 16 2013 VFR CONDITIONS WILL CONTINUE THROUGH THE FIRST PART OF THE FORECAST PERIOD. WINDS WILL BECOME MORE WESTERLY BY LATE AFTERNOON OR EARLY EVENING ALONG WITH SOME MID LEVEL CLOUDS AS A TROUGH OF LOW PRESSURE MOVES INTO THE AREA. MORE SIGNIFICANT COLD AIR WILL NOT COME DOWN UNTIL LATER TONIGHT...WITH WINDS BECOMING NORTHWESTERLY OVERNIGHT. SOME OF THE MODELS SUCH AS THE HRRR AND THE SHORT RANGE ENSEMBLES SHOW MVFR OR EVEN IFR CIGS WITH THE BOUNDARY. COVERAGE OF THE REDUCED CATEGORIES LOOKS PRETTY SCATTERED HOWEVER. LOWERED CIGS A BIT BUT KEPT THINGS AT VFR EXCEPT FOR AT KDVL WHERE THEY HAVE A BETTER CHANCE OF GETTING BELOW 3000 FT. CONTINUED WITH VCSH...ALTHOUGH WITH LIMITED MOISTURE DO NOT THINK THE SHOWERS WILL BE MUCH MORE THAN SPRINKLES. ANY LOWER CIGS WILL DISSIPATE AFTER 16Z OR SO. && .HYDROLOGY... A RIVER FLOOD WARNING CONTINUES ALONG THE RED RIVER AT WAHPETON...WITH RIVER FLOOD WATCHES REMAINING IN EFFECT ALONG THE RED RIVER AT FARGO...S BRANCH BUFFALO RIVER AT SABIN...AND BUFFALO RIVER NEAR DILWORTH. RIVER RISES CONTINUE OVER SECTIONS OF THE RED RIVER AND AREA TRIBUTARIES. RIVER RISES WILL NEED TO BE MONITORED...WITH SOME UNCERTAINTY REGARDING THE DEGREE OF RIVER RISES. BASED ON CURRENT DATA...RISES ARE BEGINNING TO SLOW AT WAHPETON...ALONG THE S BUFFALO RIVER NEAR SABIN...AND ALONG THE WILD RICE RIVER AT ABERCROMBIE. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...GODON SHORT TERM...DK LONG TERM...DK/MAKOWSKI AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1154 PM CDT TUE OCT 15 2013 .UPDATE... ISSUED AT 1148 PM CDT TUE OCT 15 2013 HIGH PRESSURE RIDGE INTO EAST CENTRAL ND ATTM...WITH TEMPS HOLDING 30-32 IN NORTHEAST INTO ECNTRL-CNTRL ND AND FAR NW MN. CLOUDS SLOWLY BUT SURELY TRYING TO CLEAR FROM THE NORTH-NORTHEAST AND JUST CLEARED FARGO AT 05Z. LATEST RAP SHOWS CLEARING EXITING SOUTHEAST FCST AREA BY 11Z SO STILL TIME FOR WCNTRL MN TO COOL OFF BEFORE DAYBREAK. LEFT LOWS THERE ALONE WITH LOWER 30S AS WELL. COULD BE SOME PATCHY FOG BUT NOT IN GRIDDS ATTM. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 252 PM CDT TUE OCT 15 2013 MAIN ISSUES WILL BE TIMING OF THE CLEARING OUT AND ENDING OF RAIN AS WELL AS TEMPERATURES THROUGHOUT THE PERIOD. THE UPPER LOW CURRENTLY ROTATING OVER MN WILL MOVE OFF INTO THE GREAT LAKES TONIGHT. RAIN WILL END OVER THE FAR SOUTHEASTERN COUNTIES FAIRLY EARLY THIS EVENING AS THE SFC LOW PULLS AWAY FROM THE AREA. IT LOOKS LIKE THERE WILL BE SOME PRESSURE GRADIENT AND WEST WINDS WILL KEEP US FROM COMPLETELY DECOUPLING. HOWEVER...DEW POINTS WILL BE DOWN INTO THE LOW 30S WITH EVEN SOME 20S NOT OUT OF THE QUESTION. SKIES WILL CLEAR OUT THIS EVENING. MODELS SHOW SOME HIGH RH VALUES APPROACHING FROM CANADA BY EARLY WEDNESDAY MORNING...BUT THINK THAT SKIES WILL STILL BE CLEAR ENOUGH TO GET PRETTY COLD. CONTINUED TREND OF TEMPS NEAR TO A FEW DEGREES BELOW THE FREEZING MARK. GIVEN THE LATENESS OF THE TIME OF YEAR WILL FORGO ANY HEADLINES AND ISSUE A PNS ABOUT THE END OF THE GROWING SEASON. TOMORROW SHOULD BE PRETTY QUIET WITH NEAR SEASONAL TEMPS AS NEAR ZONAL FLOW BRIEFLY SETS UP BETWEEN SYSTEMS. WESTERLY WINDS AND SUNSHINE SHOULD HELP TEMPS CLIMB INTO THE MID TO UPPER 50S. THE WARM TREND WILL BE SHORT LIVED AS ANOTHER COLD FRONT MOVES IN WEDNESDAY NIGHT. WILL CONTINUE TO KEEP SOME LOW POPS FOR LATE WEDNESDAY NIGHT AS THE FRONT MOVES THROUGH...ALTHOUGH THE NAM KEEPS MOST OF THE PRECIP TO OUR SOUTHWEST. THE OTHER MODELS CONTINUE TO SHOW SOME SCATTERED QPF SO KEPT THE SLIGHT MENTION GOING. LOWS WEDNESDAY NIGHT WILL BE A BIT WARMER THAN TUESDAY NIGHT WITH CLOUDS AND WINDS KEEPING US MIXED. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 252 PM CDT TUE OCT 15 2013 THURSDAY...THE COLD FRONT WILL CONTINUE TO PUSH ITS WAY ACROSS THE REGION. THERE SHOULD STILL BE A SLIGHT CHANCE FOR SHOWERS THURSDAY MORNING AS THE MODELS SHOW SOME WEAK FRONTOGENESIS MOVING THROUGH. TEMPS WILL BE COOLING AN MAY EVEN SHOW A NON-DIURNAL TREND AS COLD AIR ADVECTION BRINGS 850MB TEMPS DOWN BELOW THE FREEZING MARK. WIND WILL LIGHTEN AND SHIFT TO THE WEST THURSDAY NIGHT...ALTHOUGH LINGERING CLOUDS SHOULD KEEP TEMPS IN THE MID 30S. A REINFORCING SURGE OF COLD AIR WILL COME DOWN FRIDAY...KEEPING TEMPS IN THE 40S WITH SOME SCATTERED SHOWERS AS A WEAK UPPER SHORTWAVE MOVES THROUGH. FOR THE FRI NIGHT THROUGH TUE TIME PERIOD THE REGION REMAINS IN SHARP NORTHWEST FLOW ALOFT. MAIN FORECAST CHALLENGE WILL BE TIMING ANY WEAK EMBEDDED IMPULSES IN THE FLOW THAT MAY PRODUCE PCPN. AT THIS POINT THERE IS ONE FOR FRI NIGHT INTO SAT...ANOTHER ON SUN AND SUN NIGHT WITH A THIRD MON NIGHT INTO TUE. NONE OF THESE SYSTEMS ARE PARTICULARLY IMPRESSIVE AND WILL NOT LEAD TO ANY HEAVY PCPN. HOWEVER SOME LIGHT RAIN POSSIBLY CHANGING TO LIGHT SNOW AT NIGHT WILL BE POSSIBLE. TEMPS LOOK TO STAY ON THE CHILLY SIDE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1148 PM CDT TUE OCT 15 2013 BEMIDJI CLOUD DECK RISING TO VFR LEVELS AT 05Z WITH CLEARING NOW OVER LOWER RED LAKE...EXPECT BEMIDJI TO CLEAR OUT BY 08Z. CLEAR AT FARGO NOW. EXPECT CLEAR SKY AT REST OF THE AREA THRU WED AM WITH A NORTHWEST WIND TURNING MORE WEST OR WEST-SOUTHWEST TOWARD WED AM. HIGH CLOUD COVER TO INCREASE FROM NORTHWEST TO SOUTHEAST WEDNESDAY MIDDAY-AFTN AHD OF NEXT TROUGH WHICH WILL ENTER NE ND WED AFTN THEN MOVE THRU REST OF THE AREA WED EVE SWITCHING WINDS TO THE NORTHWEST. SOME MID CLOUD COVER LIKELY ALONG OR BEHIND FRONT. && .HYDROLOGY... ISSUED AT 1148 PM CDT TUE OCT 15 2013 BASED ON RISES AT RED RIVER AT WAHPETON AND EXPECTED RISE ABOVE FLOOD STAGE WED AFTN....ISSUED A RIVER FLOOD WARNING THERE. KEPT RIVER FLOOD WATCHES FOR SABIN...DILWORTH AND FARGO AS RISES TO ABOVE FLOOD STAGE MORE THAN 24 HOURS AWAY AND STILL WANT TO SEE RIVER RESPONSES FROM RAIN. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...RIDDLE SHORT TERM...JR LONG TERM...JR/GODON AVIATION...RIDDLE HYDROLOGY...HOPPES/RIDDLE
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
315 PM CDT WED OCT 16 2013 .DISCUSSION... CURRENTLY...A COLD FRONT STRETCHES FROM EASTERN KENTUCKY THROUGH KCBM INTO LOUISIANA. THE RAIN SHIELD IS PROGRESSING TO THE EAST AND NOW COVERS AREAS GENERALLY SOUTH OF I-40 AND EAST OF I-55. CLOUDS COVER MOST OF THE REST OF THE MIDSOUTH THOUGH THE SUN IS TEMPORARILY PEAKING OUT ACROSS PARTS OF NORTHEAST ARKANSAS. TEMPS ARE WELL BELOW NORMAL AS MUCH COOLER AIR FILTERS IN WITH READINGS HOVERING AROUND 60 WITH A LIGHT NNW WIND. TONIGHT...THE COLD FRONT WILL PUSH SLOWLY EAST. MEANWHILE A WEAK LOW PRESSURE SYSTEM WILL RIDE NORTHEAST ALONG THE FRONT AS A PIECE OF UPPER LEVEL ENERGY NOW MOVING THROUGH THE ARKLATEX PUSHES INTO THE LOWER MISSISSIPPI VALLEY. AS A RESULT THE POST FRONTAL RAIN SHIELD SHOULD EXPAND OVERNIGHT AND PUSH ACROSS NORTH MISSISSIPPI. THE 12Z NAM AND LATEST HRRR DEPICT THIS SCENARIO WHILE THE GFS AND ECMWF ARE LESS BULLISH. WILL ALSO KEEP SMALL POPS ACROSS THE REMAINDER OF THE AREA AS A MID LEVEL SHORTWAVE PUSHES THROUGH THE MID MS VALLEY. THIS FEATURE MAY RESULT IN SOME SPOTTY LIGHT SHOWERS ACROSS THE AREA LATER THIS EVENING AND AFTER MIDNIGHT. GENERALLY WENT ABOVE TEMP GUIDANCE DUE TO CLOUDS. THURSDAY...KEPT A SMALL CHANCE OF RAIN ACROSS EASTERN SECTIONS IN THE MORNING FOLLOWED BY GRADUAL CLEARING AS HIGH PRESSURE BUILDS IN. TEMPS WILL BE A FEW DEGREES COOLER THAN NORMAL...IN THE UPPER 60S TO AROUND 70. THURSDAY NIGHT THROUGH FRIDAY...WEAK HIGH PRESSURE WILL PREVAIL WITH PLEASANT CONDS. MOSTLY CLEAR AND COOL THURSDAY NIGHT WITH LOWS IN THE 40S. EXPECT A SUNNY START TO FRIDAY FOLLOWED BY INCREASING CLOUDS IN THE AFTERNOON WITH THE APPROACH OF THE NEXT SYSTEM. HIGHS WILL BE A COUPLE OF DEGREES WARMER. FRIDAY NIGHT AND SATURDAY...A WEAK REINFORCING COLD FRONT WILL PUSH THROUGH FRIDAY NIGHT WITH THE BEST CHANCE FOR SHOWERS ALONG THE MISSOURI/KY BORDER. MODELS CONTINUE TO TREND TOWARD A DRIER FORECAST ACROSS SOUTHERN AREAS WITH THE LOW PRESSURE ALONG THE GULF REMAINING WELL TO THE SOUTH. WILL LEAVE IN SLIGHT CHANCE POPS ACROSS THE SOUTH FOR NOW BUT THESE MAY NEED TO BE PULLED IF CURRENT TRENDS HOLD. EXPECT SOME CLEARING BY SATURDAY AFTERNOON WITH SEASONABLY COOL TEMPS. SUNDAY THROUGH WEDNESDAY...LOOKS LIKE A PLEASANT STRETCH OF WEATHER WITH HIGH PRESSURE AT THE SURFACE AND COOL WNW FLOW ALOFT. A COUPLE OF WEAK REINFORCING FRONT PUSH THROUGH ON TUESDAY AND AGAIN ON WEDNESDAY BUT THEY ARE MOISTURE STARVED SO REMOVED MENTION OF POPS FOR NOW. TEMPS WILL BE SEASONABLE THEN TURNING COOLER BY MIDWEEK. LONG RANGE MODELS ARE HINTING AT A VERY COOL AIRMASS PUSHING IN BY THU OR FRI OF NEXT WEEK. SJM && .AVIATION... 18Z TAF CYCLE RAIN WILL CONTINUE TO DISSIPATE FROM NORTH TO SOUTH ACROSS THE REGION AS THE FRONT MOVES SOUTHWARD TODAY. CIGS REMAIN MVFR AT NEARLY ALL SITES AS THE POST FRONTAL CLOUDS CONTINUE TO MOVE EAST. RAIN WILL CONTINUE TO AFFECT MKL AND TUP AS ANOTHER UPPER LEVEL WAVE LIFTS THROUGH LATER TODAY. SHOWERS WILL EVENTUALLY TAPER OFF NEAR THE END OF THE PERIOD NEAR TUP. EXPECT MVFR CIGS TO REMAIN AT ALL SITES THROUGH MOST OF THE PERIOD...EXCEPT FOR JBR WHERE CIGS WILL BECOME VFR BY 21Z. SOME OVERNIGHT FOG WILL KEEP MVFR CONDS AT MEM...MKL...AND TUP...BEFORE CLEARING OUT AROUND SUNRISE TOMORROW...THEREAFTER VFR CONDS TO PREVAIL. WINDS WILL REMAIN FROM THE NORTH AT 3-7 KTS. AC3 && .PRELIMINARY POINT TEMPS/POPS... MEM 55 69 49 73 / 30 10 10 10 MKL 53 67 40 70 / 30 20 10 10 JBR 51 68 43 72 / 20 10 10 10 TUP 57 70 47 72 / 70 20 10 10 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
113 PM CDT WED OCT 16 2013 .UPDATE... UPDATED FOR 18Z AVIATION DISCUSSION. && .DISCUSSION... A COLD FRONT STRETCHES FROM CENTRAL KENTUCKY THROUGH TUPELO INTO THE LOUISIANA. POST FRONTAL RAIN COVERS A GOOD POSITION OF THE MIDSOUTH INCLUDING MOST OF WEST TENNESSEE...NORTH MISSISSIPPI AND EAST CENTRAL ARKANSAS. RAIN HAS ENDED ACROSS MOST OF NORTHEAST ARKANSAS AND THE MISSOURI BOOTHEEL. MUCH COOLER AIR IS MOVING IN BEHIND THE FRONT WITH TEMPS IN THE MID AND UPPER 50S BEHIND THE FRONT. STILL MILD AHEAD OF THE FRONT WITH TEMPS IN THE MID AND UPPER 60S ACROSS NORTHEAST MISSISSIPPI. GIVEN THE AREAL COVERAGE ATTM AND THE LATEST HRRR HAVE UPPED POPS ACROSS MUCH THE SE HALF OF THE FORECAST AREA FOR THIS AFTERNOON. SJM && A COLD FRONT CURRENTLY STRETCHES FROM NEAR EVANSVILLE INDIANA TO PINE BLUFF ARKANSAS. A LARGE SHIELD OF RAIN IS PUSHING NORTHEAST ALONG THE FRONT. THE NORTHERN EDGE OF THE RAIN IS FURTHER NORTH THAN WHAT THE GFS AND NAM INITIALIZED WITH THUS FOR THIS MORNINGS FORECAST HAVE LEANED TOWARD THE LATEST HRRR RUN. THUS EXPECT RAIN TO CONTINUE TO FALL OVER AT LEAST THE NORTHWEST HALF OF THE CWA...MAINLY NORTHWEST OF A LINE FROM CLARKSDALE MISSISSIPPI TO JACKSON TENNESSEE THROUGH 10 AM. THEREAFTER...EXPECT RAIN TO GRADUALLY SHIFT SOUTHEAST AS THE DAY PROGRESSES. RAIN AND CLOUDS WILL KEEP TEMPERATURES COOL WITH A LOT OF LOCATIONS HAVING TEMPERATURES HOLD STEADY THROUGHOUT THE DAY FROM WHAT THEIR MORNING LOWS ARE. TONIGHT...EXPECT FRONT TO BE LOCATED ACROSS NORTHEAST MISSISSIPPI. MODELS INDICATING ANOTHER WEAK LOW PRESSURE CENTER DEVELOPING ALONG THE FRONT AS A SHORTWAVE MOVES INTO NORTHEAST ARKANSAS THIS EVENING. RAIN WILL SPREAD BACK NORTHWARD. ALTHOUGH A LOT OF THE PRECIPITATION WILL FALL AS VERY LIGHT RAIN OR POSSIBLY DRIZZLE SO EXPECT RAINFALL AMOUNTS TO BE ON THE LIGHT SIDE. LOWS WILL BE IN THE UPPER 40S TO UPPER 50S. THURSDAY...SHORTWAVE WILL FINALLY PUSH THE FRONT EAST OF THE AREA. EXPECT LIGHT RAIN/DRIZZLE AND CLOUDS TO REMAIN AROUND AT LEAST EASTERN PORTIONS OF THE MIDSOUTH IN THE MORNING. CONDITIONS WILL QUICKLY IMPROVE DURING THE AFTERNOON HOURS WITH A LOT OF LOCATIONS SEEING SUNSHINE BY THE END OF THE DAY. EXPECT HIGHS IN THE MID TO UPPER 60S. THURSDAY NIGHT INTO FRIDAY...SFC HIGH PRESSURE WILL BUILD OVER THE MIDSOUTH. MOSTLY CLEAR SKIES AND LIGHT WINDS WILL ALLOW LOWS TO DROP DOWN INTO THE 40S ACROSS THE ENTIRE CWA. WOULD NOT BE SURPRISED TO SEE A FEW UPPER 30 READINGS ALONG THE TENNESSEE RIVER. FRIDAY NIGHT INTO SATURDAY...MODELS ARE TRENDING TOWARD A DRIER FORECAST DURING THIS TIME FRAME. LOOKS LIKE THE LOW PRESSURE SYSTEM THAT DEVELOPS ALONG THE GULF COAST WILL BE FAR ENOUGH SOUTH TO KEEP RAIN FROM SPREADING BACK INTO THE AREA. CAN/T RULE OUT THE NORTHERN EDGE OF RAIN SKIRTING AREAS IN TALLAHATCHIE TO MONROE COUNTIES IN MISSISSIPPI ON SATURDAY THUS HAVE LEFT SMALL POPS. IN ADDITION...THERE WILL BE A REINFORCING COLD FRONT THAT MOVES INTO THE AREA LATE FRIDAY NIGHT INTO SATURDAY FROM THE NORTH. GFS SHOWS THE FRONT MOVING THROUGH DRY WHILE THE ECMWF SHOWS VERY LIGHT QPF OVER THE AREA. FOR NOW HAVE JUST KEPT 20 POPS ACROSS THE ENTIRE CWA BUT WOULD NOT BE SURPRISED IF THE DAY SHIFT WILL BE ABLE TO REMOVE CHANCES. HIGH PRESSURE WILL SETTLE BACK OVER THE CWA FOR THE LATTER PART OF THE WEEKEND INTO EARLY NEXT WEEK. EXPECT SUNDAY NIGHT TO BE ANOTHER CHILLY NIGHT WITH SEVERAL LOCATIONS ACROSS WEST TENNESSEE AND POSSIBLY NORTHEAST MISSISSIPPI GETTING DOWN INTO THE UPPER 30S. ANOTHER COLD FRONT OR LOW PRESSURE SYSTEM MAY AFFECT THE MIDSOUTH MONDAY NIGHT INTO TUESDAY. GFS AND ECMWF HAVE DIFFERENT SOLUTIONS WITH THE ECMWF BEING DRIER. FOR NOW HAVE ADDED 20 POPS FOR TUESDAY. KRM && .AVIATION... 18Z TAF CYCLE RAIN WILL CONTINUE TO DISSIPATE FROM NORTH TO SOUTH ACROSS THE REGION AS THE FRONT MOVES SOUTHWARD TODAY. CIGS REMAIN MVFR AT NEARLY ALL SITES AS THE POST FRONTAL CLOUDS CONTINUE TO MOVE EAST. RAIN WILL CONTINUE TO AFFECT MKL AND TUP AS ANOTHER UPPER LEVEL WAVE LIFTS THROUGH LATER TODAY. SHOWERS WILL EVENTUALLY TAPER OFF NEAR THE END OF THE PERIOD NEAR TUP. EXPECT MVFR CIGS TO REMAIN AT ALL SITES THROUGH MOST OF THE PERIOD...EXCEPT FOR JBR WHERE CIGS WILL BECOME VFR BY 21Z. SOME OVERNIGHT FOG WILL KEEP MVFR CONDS AT MEM...MKL...AND TUP...BEFORE CLEARING OUT AROUND SUNRISE TOMORROW...THENAFTER VFR CONDS TO PREVAIL. WINDS WILL REMAIN FROM THE NORTH AT 3-7 KTS. AC3 && .PRELIMINARY POINT TEMPS/POPS... MEM 63 55 69 47 / 80 30 20 10 MKL 62 54 66 40 / 90 30 20 10 JBR 65 49 67 42 / 30 20 10 10 TUP 69 57 67 47 / 90 50 30 10 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1026 AM CDT WED OCT 16 2013 .DISCUSSION... A COLD FRONT STRETCHES FROM CENTRAL KENTUCKY THROUGH TUPELO INTO THE LOUISIANA. POST FRONTAL RAIN COVERS A GOOD POSITION OF THE MIDSOUTH INCLUDING MOST OF WEST TENNESSEE...NORTH MISSISSIPPI AND EAST CENTRAL ARKANSAS. RAIN HAS ENDED ACROSS MOST OF NORTHEAST ARKANSAS AND THE MISSOURI BOOTHEEL. MUCH COOLER AIR IS MOVING IN BEHIND THE FRONT WITH TEMPS IN THE MID AND UPPER 50S BEHIND THE FRONT. STILL MILD AHEAD OF THE FRONT WITH TEMPS IN THE MID AND UPPER 60S ACROSS NORTHEAST MISSISSIPPI. GIVEN THE AREAL COVERAGE ATTM AND THE LATEST HRRR HAVE UPPED POPS ACROSS MUCH THE SE HALF OF THE FORECAST AREA FOR THIS AFTERNOON. SJM && PREV DISCUSSION... /ISSUED 248 AM CDT WED OCT 16 2013/ A COLD FRONT CURRENTLY STRETCHES FROM NEAR EVANSVILLE INDIANA TO PINE BLUFF ARKANSAS. A LARGE SHIELD OF RAIN IS PUSHING NORTHEAST ALONG THE FRONT. THE NORTHERN EDGE OF THE RAIN IS FURTHER NORTH THAN WHAT THE GFS AND NAM INITIALIZED WITH THUS FOR THIS MORNINGS FORECAST HAVE LEANED TOWARD THE LATEST HRRR RUN. THUS EXPECT RAIN TO CONTINUE TO FALL OVER AT LEAST THE NORTHWEST HALF OF THE CWA...MAINLY NORTHWEST OF A LINE FROM CLARKSDALE MISSISSIPPI TO JACKSON TENNESSEE THROUGH 10 AM. THEREAFTER...EXPECT RAIN TO GRADUALLY SHIFT SOUTHEAST AS THE DAY PROGRESSES. RAIN AND CLOUDS WILL KEEP TEMPERATURES COOL WITH A LOT OF LOCATIONS HAVING TEMPERATURES HOLD STEADY THROUGHOUT THE DAY FROM WHAT THEIR MORNING LOWS ARE. TONIGHT...EXPECT FRONT TO BE LOCATED ACROSS NORTHEAST MISSISSIPPI. MODELS INDICATING ANOTHER WEAK LOW PRESSURE CENTER DEVELOPING ALONG THE FRONT AS A SHORTWAVE MOVES INTO NORTHEAST ARKANSAS THIS EVENING. RAIN WILL SPREAD BACK NORTHWARD. ALTHOUGH A LOT OF THE PRECIPITATION WILL FALL AS VERY LIGHT RAIN OR POSSIBLY DRIZZLE SO EXPECT RAINFALL AMOUNTS TO BE ON THE LIGHT SIDE. LOWS WILL BE IN THE UPPER 40S TO UPPER 50S. THURSDAY...SHORTWAVE WILL FINALLY PUSH THE FRONT EAST OF THE AREA. EXPECT LIGHT RAIN/DRIZZLE AND CLOUDS TO REMAIN AROUND AT LEAST EASTERN PORTIONS OF THE MIDSOUTH IN THE MORNING. CONDITIONS WILL QUICKLY IMPROVE DURING THE AFTERNOON HOURS WITH A LOT OF LOCATIONS SEEING SUNSHINE BY THE END OF THE DAY. EXPECT HIGHS IN THE MID TO UPPER 60S. THURSDAY NIGHT INTO FRIDAY...SFC HIGH PRESSURE WILL BUILD OVER THE MIDSOUTH. MOSTLY CLEAR SKIES AND LIGHT WINDS WILL ALLOW LOWS TO DROP DOWN INTO THE 40S ACROSS THE ENTIRE CWA. WOULD NOT BE SURPRISED TO SEE A FEW UPPER 30 READINGS ALONG THE TENNESSEE RIVER. FRIDAY NIGHT INTO SATURDAY...MODELS ARE TRENDING TOWARD A DRIER FORECAST DURING THIS TIME FRAME. LOOKS LIKE THE LOW PRESSURE SYSTEM THAT DEVELOPS ALONG THE GULF COAST WILL BE FAR ENOUGH SOUTH TO KEEP RAIN FROM SPREADING BACK INTO THE AREA. CAN/T RULE OUT THE NORTHERN EDGE OF RAIN SKIRTING AREAS IN TALLAHATCHIE TO MONROE COUNTIES IN MISSISSIPPI ON SATURDAY THUS HAVE LEFT SMALL POPS. IN ADDITION...THERE WILL BE A REINFORCING COLD FRONT THAT MOVES INTO THE AREA LATE FRIDAY NIGHT INTO SATURDAY FROM THE NORTH. GFS SHOWS THE FRONT MOVING THROUGH DRY WHILE THE ECMWF SHOWS VERY LIGHT QPF OVER THE AREA. FOR NOW HAVE JUST KEPT 20 POPS ACROSS THE ENTIRE CWA BUT WOULD NOT BE SURPRISED IF THE DAY SHIFT WILL BE ABLE TO REMOVE CHANCES. HIGH PRESSURE WILL SETTLE BACK OVER THE CWA FOR THE LATTER PART OF THE WEEKEND INTO EARLY NEXT WEEK. EXPECT SUNDAY NIGHT TO BE ANOTHER CHILLY NIGHT WITH SEVERAL LOCATIONS ACROSS WEST TENNESSEE AND POSSIBLY NORTHEAST MISSISSIPPI GETTING DOWN INTO THE UPPER 30S. ANOTHER COLD FRONT OR LOW PRESSURE SYSTEM MAY AFFECT THE MIDSOUTH MONDAY NIGHT INTO TUESDAY. GFS AND ECMWF HAVE DIFFERENT SOLUTIONS WITH THE ECMWF BEING DRIER. FOR NOW HAVE ADDED 20 POPS FOR TUESDAY. KRM && .AVIATION... 12Z TAF CYCLE LIGHT RAIN CONTINUES TO FALL OVER PORTIONS OF THE FORECAST AREA AND WILL CONTINUE TO MOVE ACROSS THE FORECAST AREA DURING MUCH OF THE FORECAST PERIOD. CEILINGS WILL BEGIN TO IMPROVE AFTER SUNRISE BUT LIKELY REMAIN MVFR AT ALL SITES WITH THE EXCEPTION OF JBR WHERE VFR CONDITIONS SHOULD PREVAIL. WINDS WILL SHIFT FROM THE NORTH...INCREASING TO AROUND 10 KTS TODAY...DIMINISHING SLIGHTLY TONIGHT. && .PRELIMINARY POINT TEMPS/POPS... MEM 63 55 69 47 / 80 30 20 10 MKL 62 54 66 40 / 90 30 20 10 JBR 65 49 67 42 / 30 20 10 10 TUP 69 57 67 47 / 90 50 30 10 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
628 AM CDT WED OCT 16 2013 .UPDATE...AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 248 AM CDT WED OCT 16 2013/ DISCUSSION... A COLD FRONT CURRENTLY STRETCHES FROM NEAR EVANSVILLE INDIANA TO PINE BLUFF ARKANSAS. A LARGE SHIELD OF RAIN IS PUSHING NORTHEAST ALONG THE FRONT. THE NORTHERN EDGE OF THE RAIN IS FURTHER NORTH THAN WHAT THE GFS AND NAM INITIALIZED WITH THUS FOR THIS MORNINGS FORECAST HAVE LEANED TOWARD THE LATEST HRRR RUN. THUS EXPECT RAIN TO CONTINUE TO FALL OVER AT LEAST THE NORTHWEST HALF OF THE CWA...MAINLY NORTHWEST OF A LINE FROM CLARKSDALE MISSISSIPPI TO JACKSON TENNESSEE THROUGH 10 AM. THEREAFTER...EXPECT RAIN TO GRADUALLY SHIFT SOUTHEAST AS THE DAY PROGRESSES. RAIN AND CLOUDS WILL KEEP TEMPERATURES COOL WITH A LOT OF LOCATIONS HAVING TEMPERATURES HOLD STEADY THROUGHOUT THE DAY FROM WHAT THEIR MORNING LOWS ARE. TONIGHT...EXPECT FRONT TO BE LOCATED ACROSS NORTHEAST MISSISSIPPI. MODELS INDICATING ANOTHER WEAK LOW PRESSURE CENTER DEVELOPING ALONG THE FRONT AS A SHORTWAVE MOVES INTO NORTHEAST ARKANSAS THIS EVENING. RAIN WILL SPREAD BACK NORTHWARD. ALTHOUGH A LOT OF THE PRECIPITATION WILL FALL AS VERY LIGHT RAIN OR POSSIBLY DRIZZLE SO EXPECT RAINFALL AMOUNTS TO BE ON THE LIGHT SIDE. LOWS WILL BE IN THE UPPER 40S TO UPPER 50S. THURSDAY...SHORTWAVE WILL FINALLY PUSH THE FRONT EAST OF THE AREA. EXPECT LIGHT RAIN/DRIZZLE AND CLOUDS TO REMAIN AROUND AT LEAST EASTERN PORTIONS OF THE MIDSOUTH IN THE MORNING. CONDITIONS WILL QUICKLY IMPROVE DURING THE AFTERNOON HOURS WITH A LOT OF LOCATIONS SEEING SUNSHINE BY THE END OF THE DAY. EXPECT HIGHS IN THE MID TO UPPER 60S. THURSDAY NIGHT INTO FRIDAY...SFC HIGH PRESSURE WILL BUILD OVER THE MIDSOUTH. MOSTLY CLEAR SKIES AND LIGHT WINDS WILL ALLOW LOWS TO DROP DOWN INTO THE 40S ACROSS THE ENTIRE CWA. WOULD NOT BE SURPRISED TO SEE A FEW UPPER 30 READINGS ALONG THE TENNESSEE RIVER. FRIDAY NIGHT INTO SATURDAY...MODELS ARE TRENDING TOWARD A DRIER FORECAST DURING THIS TIME FRAME. LOOKS LIKE THE LOW PRESSURE SYSTEM THAT DEVELOPS ALONG THE GULF COAST WILL BE FAR ENOUGH SOUTH TO KEEP RAIN FROM SPREADING BACK INTO THE AREA. CAN/T RULE OUT THE NORTHERN EDGE OF RAIN SKIRTING AREAS IN TALLAHATCHIE TO MONROE COUNTIES IN MISSISSIPPI ON SATURDAY THUS HAVE LEFT SMALL POPS. IN ADDITION...THERE WILL BE A REINFORCING COLD FRONT THAT MOVES INTO THE AREA LATE FRIDAY NIGHT INTO SATURDAY FROM THE NORTH. GFS SHOWS THE FRONT MOVING THROUGH DRY WHILE THE ECMWF SHOWS VERY LIGHT QPF OVER THE AREA. FOR NOW HAVE JUST KEPT 20 POPS ACROSS THE ENTIRE CWA BUT WOULD NOT BE SURPRISED IF THE DAY SHIFT WILL BE ABLE TO REMOVE CHANCES. HIGH PRESSURE WILL SETTLE BACK OVER THE CWA FOR THE LATTER PART OF THE WEEKEND INTO EARLY NEXT WEEK. EXPECT SUNDAY NIGHT TO BE ANOTHER CHILLY NIGHT WITH SEVERAL LOCATIONS ACROSS WEST TENNESSEE AND POSSIBLY NORTHEAST MISSISSIPPI GETTING DOWN INTO THE UPPER 30S. ANOTHER COLD FRONT OR LOW PRESSURE SYSTEM MAY AFFECT THE MIDSOUTH MONDAY NIGHT INTO TUESDAY. GFS AND ECMWF HAVE DIFFERENT SOLUTIONS WITH THE ECMWF BEING DRIER. FOR NOW HAVE ADDED 20 POPS FOR TUESDAY. KRM .AVIATION... 12Z TAF CYCLE LIGHT RAIN CONTINUES TO FALL OVER PORTIONS OF THE FORECAST AREA AND WILL CONTINUE TO MOVE ACROSS THE FORECAST AREA DURING MUCH OF THE FORECAST PERIOD. CEILINGS WILL BEGIN TO IMPROVE AFTER SUNRISE BUT LIKELY REMAIN MVFR AT ALL SITES WITH THE EXCEPTION OF JBR WHERE VFR CONDITIONS SHOULD PREVAIL. WINDS WILL SHIFT FROM THE NORTH...INCREASING TO AROUND 10 KTS TODAY...DIMINISHING SLIGHTLY TONIGHT. && .PRELIMINARY POINT TEMPS/POPS... MEM 63 55 69 47 / 100 30 20 10 MKL 62 54 66 40 / 100 30 20 10 JBR 65 49 67 42 / 90 20 10 10 TUP 69 57 67 47 / 90 50 30 10 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
248 AM CDT WED OCT 16 2013 .DISCUSSION... A COLD FRONT CURRENTLY STRETCHES FROM NEAR EVANSVILLE INDIANA TO PINE BLUFF ARKANSAS. A LARGE SHIELD OF RAIN IS PUSHING NORTHEAST ALONG THE FRONT. THE NORTHERN EDGE OF THE RAIN IS FURTHER NORTH THAN WHAT THE GFS AND NAM INITIALIZED WITH THUS FOR THIS MORNINGS FORECAST HAVE LEANED TOWARD THE LATEST HRRR RUN. THUS EXPECT RAIN TO CONTINUE TO FALL OVER AT LEAST THE NORTHWEST HALF OF THE CWA...MAINLY NORTHWEST OF A LINE FROM CLARKSDALE MISSISSIPPI TO JACKSON TENNESSEE THROUGH 10 AM. THEREAFTER...EXPECT RAIN TO GRADUALLY SHIFT SOUTHEAST AS THE DAY PROGRESSES. RAIN AND CLOUDS WILL KEEP TEMPERATURES COOL WITH A LOT OF LOCATIONS HAVING TEMPERATURES HOLD STEADY THROUGHOUT THE DAY FROM WHAT THEIR MORNING LOWS ARE. TONIGHT...EXPECT FRONT TO BE LOCATED ACROSS NORTHEAST MISSISSIPPI. MODELS INDICATING ANOTHER WEAK LOW PRESSURE CENTER DEVELOPING ALONG THE FRONT AS A SHORTWAVE MOVES INTO NORTHEAST ARKANSAS THIS EVENING. RAIN WILL SPREAD BACK NORTHWARD. ALTHOUGH A LOT OF THE PRECIPITATION WILL FALL AS VERY LIGHT RAIN OR POSSIBLY DRIZZLE SO EXPECT RAINFALL AMOUNTS TO BE ON THE LIGHT SIDE. LOWS WILL BE IN THE UPPER 40S TO UPPER 50S. THURSDAY...SHORTWAVE WILL FINALLY PUSH THE FRONT EAST OF THE AREA. EXPECT LIGHT RAIN/DRIZZLE AND CLOUDS TO REMAIN AROUND AT LEAST EASTERN PORTIONS OF THE MIDSOUTH IN THE MORNING. CONDITIONS WILL QUICKLY IMPROVE DURING THE AFTERNOON HOURS WITH A LOT OF LOCATIONS SEEING SUNSHINE BY THE END OF THE DAY. EXPECT HIGHS IN THE MID TO UPPER 60S. THURSDAY NIGHT INTO FRIDAY...SFC HIGH PRESSURE WILL BUILD OVER THE MIDSOUTH. MOSTLY CLEAR SKIES AND LIGHT WINDS WILL ALLOW LOWS TO DROP DOWN INTO THE 40S ACROSS THE ENTIRE CWA. WOULD NOT BE SURPRISED TO SEE A FEW UPPER 30 READINGS ALONG THE TENNESSEE RIVER. FRIDAY NIGHT INTO SATURDAY...MODELS ARE TRENDING TOWARD A DRIER FORECAST DURING THIS TIME FRAME. LOOKS LIKE THE LOW PRESSURE SYSTEM THAT DEVELOPS ALONG THE GULF COAST WILL BE FAR ENOUGH SOUTH TO KEEP RAIN FROM SPREADING BACK INTO THE AREA. CAN/T RULE OUT THE NORTHERN EDGE OF RAIN SKIRTING AREAS IN TALLAHATCHIE TO MONROE COUNTIES IN MISSISSIPPI ON SATURDAY THUS HAVE LEFT SMALL POPS. IN ADDITION...THERE WILL BE A REINFORCING COLD FRONT THAT MOVES INTO THE AREA LATE FRIDAY NIGHT INTO SATURDAY FROM THE NORTH. GFS SHOWS THE FRONT MOVING THROUGH DRY WHILE THE ECMWF SHOWS VERY LIGHT QPF OVER THE AREA. FOR NOW HAVE JUST KEPT 20 POPS ACROSS THE ENTIRE CWA BUT WOULD NOT BE SURPRISED IF THE DAY SHIFT WILL BE ABLE TO REMOVE CHANCES. HIGH PRESSURE WILL SETTLE BACK OVER THE CWA FOR THE LATTER PART OF THE WEEKEND INTO EARLY NEXT WEEK. EXPECT SUNDAY NIGHT TO BE ANOTHER CHILLY NIGHT WITH SEVERAL LOCATIONS ACROSS WEST TENNESSEE AND POSSIBLY NORTHEAST MISSISSIPPI GETTING DOWN INTO THE UPPER 30S. ANOTHER COLD FRONT OR LOW PRESSURE SYSTEM MAY AFFECT THE MIDSOUTH MONDAY NIGHT INTO TUESDAY. GFS AND ECMWF HAVE DIFFERENT SOLUTIONS WITH THE ECMWF BEING DRIER. FOR NOW HAVE ADDED 20 POPS FOR TUESDAY. KRM && .AVIATION... 06Z TAF CYCLE LIGHT RAIN CONTINUES TO FALL OVER PORTIONS OF THE FORECAST AREA AND WILL CONTINUE TO MOVE ACROSS THE FORECAST AREA DURING MUCH OF THE FORECAST PERIOD. CEILINGS WILL LOWER OVERNIGHT WITH IFR CEILINGS EXPECTED BY WEDNESDAY MORNING. CEILINGS WILL BEGIN TO IMPROVE BY WEDNESDAY EVENING AND REACH VFR CONDITIONS AT KJBR AND MVFR CONDITIONS AT KMEM AND KTUP. WINDS WILL BE LIGHT AND MAINLY FROM THE SOUTH TONIGHT AND GRADUALLY SHIFT TO THE NORTHWEST ON WEDNESDAY. && .PRELIMINARY POINT TEMPS/POPS... MEM 63 55 69 47 / 100 30 20 10 MKL 62 54 66 40 / 100 30 20 10 JBR 65 49 67 42 / 90 20 10 10 TUP 69 57 67 47 / 90 50 30 10 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1149 PM CDT TUE OCT 15 2013 .UPDATE...FOR 06Z AVIATION. && .AVIATION...06Z TAF DISCUSSION. PRECIPITATION CONTINUES TO TAKE ITS TIME GETTING INTO MIDDLE TENNESSEE...BUT DON`T WORRY. IT WILL GET HERE. WILL SHOW VFR THROUGH MOST OF THE NIGHT...BUT HAVE INTRODUCED SOME IFR INTO THE PREVAILING FOR CKV AND BNA BASED ON CURRENT UPSTREAM TRENDS. FLIGHT CATEGORIES SHOULD IMPROVE TO MVFR AS WE REACH THE AFTERNOON HOURS AT THESE SITES...BUT WIDESPREAD RAINS WILL LIKELY WREAK HAVOC ON CIGS AND VIS THROUGHOUT THE DAY...ESPECIALLY WITH ANY HEAVIER RAINS. WINDS WILL BE SLOW TO SHIFT AS THE FRONT ASSOCIATED WITH THESE RAINS DRAGS THROUGH MIDDLE TENNESSEE. SHOULD SEE A SHIFT TO THE NW AT CKV BY 12Z...BUT MAY BE MID-AFTERNOON BEFORE KBNA SEES IT. EITHER WAY...WINDS ARE EXPECTED TO BE LIGHT. UNGER && .PREV DISCUSSION... /ISSUED 733 PM CDT TUE OCT 15 2013/ UPDATE...LATEST SURFACE MAP SHOWS THE COLD FRONT EAST OF ST. LOUIS AND LITTLE ROCK, WITH WIDESPREAD SHOWERS WEST OF MIDDLE TENNESSEE. HOWEVER, THE ONGOING ACTIVITY IS HAVING A HARD TIME MAKING EASTWARD PROGRESSION GIVEN THE DRIER, STABLE AIR OF MIDDLE TENNESSEE. LATEST HRRR IS OVERPLAYING CURRENT PRECIPITATION, AND EVEN THEN SHOWS LITTLE ACTIVITY MAKING IT EAST OF I-65 PRIOR TO 06Z. THEREFORE, AM SCALING BACK EVENING POP`S, BUT MAKING NO CHANCES THEREAFTER. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 27
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
932 PM CDT THU OCT 17 2013 .UPDATE... UPDATED TO BOOST LOW CLOUD COVERAGE AFTER MIDNIGHT AND ALSO TO ADD MENTION OF FOG AND DRIZZLE ON THE CAPROCK EARLY FRI MORNING. THE 02Z SURFACE PATTERN PAINTS A PRETTY CLASSIC PICTURE FOR SUCH A SCENARIO LATER TONIGHT AS DEWPOINTS IN THE PERMIAN BASIN ARE ALREADY PUSHING 60 DEGREES WITH TEMPS ON THE SOUTH PLAINS IN THE MID AND UPPER 50S. LATEST NAM AND RECENT RUNS OF THE RAP ARE CONSISTENT IN BREAKING OUT STRATUS AROUND 09Z ACROSS MUCH OF THE CAPROCK AND WESTERN PERMIAN BASIN...A BIT SIMILAR TO WHAT WE SAW LAST NIGHT IN SERN NEW MEXICO. MODEL SOUNDINGS SHOW SUFFICIENTLY THICK STRATUS HERE FOR DRIZZLE BY 12Z AND THIS IS REFLECTED BY THE NAM`S SPOTTY LIGHT QPF. DENSE FOG POTENTIAL IS A BIT LESS CERTAIN...BUT THIS WILL BE REVISITED BY THE MIDNIGHT SHIFT. ALSO REMOVED SHOWER MENTION ON THE CAPROCK FROM 12-17Z FRI AS DRIZZLE WOULD BE THE MOST WE CAN SQUEEZE OUT BEFORE THE COLD FRONT AND A BRIEF WINDOW FOR SHOWERS DEVELOP EARLY IN THE AFTERNOON JUST BEHIND THE FRONT. GIVEN MILD LOWS AND MOIST ADVECTION...RAISED OVERNIGHT LOWS SEVERAL DEGREES ON THE CAPROCK WHILE KEEPING AREAS FARTHER EAST INTACT IN LIGHT OF DRIER AIR CHARACTERIZED BY DEWPOINTS IN THE LOW/MID 40S. && .PREV DISCUSSION... /ISSUED 645 PM CDT THU OCT 17 2013/ AVIATION... VFR UNTIL LOW CIGS DEVELOP AFTER MIDNIGHT FOLLOWED BY A FAST- MOVING COLD FRONT AND GUSTY NORTH WINDS FRI AFTN. HIGH CONFIDENCE THAT MVFR AND EVEN SOME LIFR CONDS WILL DEVELOP AFTER MIDNIGHT AS INCREASINGLY MOIST SLY WINDS FOSTER A FAVORABLE SETUP FOR LOW CIGS AND PERHAPS SOME FOG. SUCH A SCENARIO OCCURRED THIS MORNING AT HOBBS AND SEMINOLE AND RECENT MODELS SUCH AS THE HRRR INDICATE WE`LL SEE DETERIORATING CONDITIONS AROUND 07Z AT LBB AND A BIT LATER AT CDS. OPTING TO KEEP LIFR MENTION TO JUST TEMPO FOR NOW...BUT THERE IS A DISTINCT POSSIBILITY THESE CIGS WILL PLUMMET AND HOLD AT LIFR VALUES THRU EARLY FRI MORNING BEFORE LIFTING TO VFR BEHIND A FAST-MOVING COLD FRONT AROUND 18Z OR SO. STILL SIDING A FEW HOURS AHEAD OF MODELS WITH THIS FROPA GIVEN THE RECENT HISTORY OF THESE FRONTS. HIGHEST NLY GUSTS AROUND 35 KNOTS FAVOR CDS WITH JUST A NARROW WINDOW FOR SHRA OR TSRA BEHIND THE FRONT. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 38 55 28 64 39 / 10 10 0 0 0 TULIA 47 53 32 65 41 / 10 20 10 0 0 PLAINVIEW 48 57 32 65 41 / 10 20 10 0 0 LEVELLAND 49 61 33 66 41 / 10 10 10 0 0 LUBBOCK 50 58 34 65 42 / 10 20 10 0 0 DENVER CITY 51 64 35 65 43 / 0 10 10 10 0 BROWNFIELD 52 63 35 65 43 / 10 10 10 0 0 CHILDRESS 51 56 36 69 44 / 20 30 20 0 0 SPUR 50 63 37 67 44 / 10 20 20 10 0 ASPERMONT 51 66 38 67 45 / 10 30 20 10 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 93
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1023 AM CDT WED OCT 16 2013 .UPDATE... SEE DISCUSSION FOR MORNING UPDATE. && .DISCUSSION... WIDESPREAD CLOUD COVER ACROSS THE CWA THIS MORNING AS A COLD FRONT LIES ACROSS WASHINGTON... GRIMES... AND TRINITY COUNTIES. THERE IS A WIND SHIFT AHEAD OF THE PRECIP WHICH APPEARS TO BE A PRE FRONTAL TROUGH. BEHIND THE FRONT TEMPERATURES ARE RIGHT AROUND 60 DEGREES AND WILL PROBABLY HAVE TROUBLE GETTING MUCH WARMER AS WIDESPREAD CLOUD COVER AND COLD AIR ADVECTION TAKES OVER. GFS AND NAM OMEGA FIELDS ARE SHOWING BEST LIFT WERE CURRENT PRECIP LIES AND PUSHING OFF TOWARDS THE NORTHEAST. THE NAM IS HINTING AT SOME LIGHTER LIFT MOVING ACROSS THE AREA BELOW THE MAIN PRECIP SHIELD. WHEN LOOKING AT THE 300K SURFACE BEST ISENTROPIC LIFT APPEARS TO BE OCCURRING NOW AND WILL BEGIN TO DISAPPEAR AS WINDS VEER NORTHWESTERLY. ALL OF THIS BEING SAID NOT SURE HOW MUCH OF THE MAIN PRECIP SHIELD WILL MAKE IT TO THE COAST BEFORE DISSIPATING. IT APPEARS THE BEST LIFT WILL BE GONE BY THEN. THERE IS A CHANCE OF SOME ISOLATED SHOWERS AHEAD OF THE MAIN PRECIP BAND BUT THESE SHOULD BE LIMITED. HAVE MADE MINOR CHANGES TO POP AND TEMPERATURE GRIDS TO ACCOUNT FOR THESE TRENDS. NEW GRIDS OUT SHORTLY. 23 && .PREV DISCUSSION... /ISSUED 643 AM CDT WED OCT 16 2013/ DISCUSSION... 12Z TAF DISCUSSION IN AVIATION SECTION. AVIATION... COLD FRONT PUSHING THROUGH HOUSTON AREA THIS MORNING WITH IFR/LIFR CIGS BEHIND THE FRONT. AREA RADAR SHOW BULK OF -RA/RA OVER C TX. EXPECT THIS TO MOVE ACROSS THE NORTHERN HALF OF SE TX DURING THE DAY. THIS SHOULD KEEP CIGS LOW FOR AT LEAST THE NEXT 6-12 HRS BEFORE IMPROVING OVERNIGHT. KCLL/KUTS/KCXO...IFR/LIFR CIGS ALREADY IN PLACE SO WILL KEEP CIGS LOW THROUGH THE NEXT 6-12HRS. EXPECT -RA/RA TO SPREAD OVER THE AREA LATE MORNING THROUGH EARLY AFTERNOON. LIKE HRRR TIMING OF PRECIP BEGIN/END SO TAF REFLECTS THAT TIMING. LOOK FOR MVFR CIGS IN THE AFTERNOON AND HOLDING THROUGH THE NIGHT. LOOKS LIKE VFR CIGS AFTER 12Z THUR. KIAH/KHOU/KSGR...COLD FRONT HAS PUSHED THROUGH KIAH/KSGR BUT JUST AT THE DOOR STEP OF KHOU. GO AHEAD WITH IFR CIGS FOR ALL TERMINALS TO START THE TAF. HAD KDWH REPORT OVC003 SO TEMPO THAT FOR A COUPLE OF HOURS GIVEN THE POSSIBILITY. LIKE HRRR TIMING OF PRECIP BUT REALLY THINK BULK OF -RA/RA WILL BE NORTH OF HOUSTON TERMINALS. WILL STILL CARRY -RA STARTING 16/17Z THROUGH 22Z THIS AFTERNOON. CIGS SHOULD IMPROVE TO MVFR IN THE EARLY AFTERNOON. KLBX/KGLS...COLD FRONT APPROACHING THESE TERMINALS THIS MORNING. EXPECT CIGS TO GO DOWN TO IFR BEHIND THE FRONT LIKE OTHER TERMINALS BUT COULD SEE ONLY MVFR. IFR/MVFR CIGS WILL BE CHALLENGING TO DETERMINE DUE TO THE COAST AND HOW AIRMASS BEHIND THE FRONT MODIFIES DURING THE DAY. WILL MENTION -RA DURING EARLY AFTERNOON BUT THINK MOST OF RAINFALL WILL BE WELL NORTH OF THE COAST. SHOULD SEE CIGS IMPROVE LATE AFTERNOON THROUGH OVERNIGHT. 39 PREV DISCUSSION... /ISSUED 508 AM CDT WED OCT 16 2013/ DISCUSSION... THE SOUTHWESTERLY FLOW ALOFT PRESENT EARLY THIS MORNING WAS DUE TO AN UPPER LEVEL HIGH PRESSURE CENTERED OVER THE SOUTHERN GULF AND AN UPPER TROUGH BETWEEN THE WESTERN GREAT LAKES AND THE SOUTHERN ROCKIES. PACIFIC MOISTURE WAS CAUGHT UP IN THE FLOW BUT WAS JUST WEST AND NORTH OF THE FORECAST AREA AT 5 AM. THE MAIN ITEMS OF CONCERN INCLUDE RAIN CHANCES AND TEMPERATURES. THE COLD FRONT WAS PUSHING ACROSS THE CENTRAL AND SOUTHERN COUNTIES EARLY THIS MORNING. THE FRONT SHOULD WORK ITS WAY OFF THE MATAGORDA COAST LATER THIS MORNING AND THEN OFF THE GALVESTON COAST LATER THIS AFTERNOON. MOST OF THE RAINFALL WAS FALLING WELL BEHIND THE FRONT AND AHEAD OF THE 850 MB TROUGH. THE MODELS DO NOT PUSH THE 850 MB TROUGH THROUGH SE TX UNTIL THURSDAY MORNING. DO EXPECT THE MAIN BULK OF THE RAIN TO PUSH INTO THE NORTHWESTERN QUARTER OF THE FORECAST AREA LATER THIS MORNING. THE HIGH PRESSURE IN THE GULF SHOULD ACTUALLY HELP THE RAIN CHANCES DROP OFF OVER THE CENTRAL AND COASTAL AREAS TODAY...ALTHOUGH CHANCES FOR RAIN WILL LINGER OVER THE SOUTHEASTERN HALF OF THE FORECAST AREA TONIGHT AND EARLY THURSDAY AS THE 850 MB TROUGH PUSHES THROUGH. DO NOT EXPECT RAINFALL AMOUNTS TODAY OR TONIGHT TO EXCEED ONE QUARTER TO ONE HALF OF AN INCH ON AVERAGE. THERE IS SOME CONSENSUSFOR A BREAK IN THE RAINY PATTERN THURSDAY AFTERNOON AND EVENING BEFORE ISENTROPIC LIFT HELPS TO RETURN RAIN CHANCES LATE THURSDAY NIGHT AND FRIDAY. THE MODELS THEN PUSH THE COASTAL FRONT EAST OF THE AREA ON SATURDAY WITH SUNDAY LOOKING DRY. BOTH THE GFS AND ECMWF BRING ANOTHER FRONTAL SYSTEM ACROSS SE TX AND RETURN RAIN CHANCES EARLY NEXT WEEK. A PERIOD OF BELOW NORMAL TEMPERATURES ARE EXPECTED THROUGH THE END OF THE WEEK. SOME LOCATIONS NEAR COLLEGE STATION MAY EVEN EXPERIENCE HIGH TEMPERATURES TODAY ALMOST 20 DEGREES BELOW NORMAL. DO EXPECT A WARMUP TO NEAR NORMAL DAYTIME TEMPERATURES TO BEGIN EARLY NEXT WEEK AHEAD OF THE NEXT COLD FRONT. 40 MARINE... COLD FRONT CURRENTLY WORKING THROUGH SE TX THIS MORNING SHOULD PUSH OFF THE COAST THIS EVENING WITH INCREASING NORTHERLY WINDS TONIGHT. MAY NEED SCEC FOR OFFSHORE WATERS BUT WILL BE BODERLINE TO ISSUE AT THIS TIME. SEAS LIKELY REMAIN AROUND 3-4FT WITH 15 KT WINDS. WINDS TURN MORE TO THE EAST FOR THE END OF THE WEEK. MEDIUM RANGE MODELS STILL SHOWING ANOTHER FRONTAL PUSH ON SATURDAY WHICH MAY BE STRONGER. LIKELY SEE SCEC CONDITIONS WITH 4-5FT SEAS OFFSHORE. NE WINDS WILL CONTINUE INTO SUNDAY WITH SEAS REMAINING AROUND 4FT IN OFFSHORE AREAS. 39 AVIATION... COLD FRONT JUST AT THE DOOR STEP OF KCXO AND KDWH. OBS BEHIND THE FRONT SHOWING IFR/LIFR CIGS SO MAY NEED TO UPDATE TAFS FOR CIGS. DO EXPECT SOME RAIN TODAY BUT THINKING IT WILL NOT BE NEARLY AS INTENSE AS PREVIOUSLY THOUGHT. GENERALLY THINK THERE WILL BE PERIODS OF LIGHT RAIN...POSSIBLY AN ISO TSRA BUT THAT LOOKS LESS LIKELY AT THIS POINT. MAIN CONCERN WILL BE HOW LONG IFR CIGS HOLD OVER SE TX BEHIND THE FRONT. 39 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 62 53 73 55 73 / 80 20 10 10 50 HOUSTON (IAH) 74 58 74 56 75 / 50 50 20 10 40 GALVESTON (GLS) 80 65 75 67 76 / 30 50 40 20 30 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...23
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
643 AM CDT WED OCT 16 2013 .DISCUSSION... 12Z TAF DISCUSSION IN AVIATION SECTION. && .AVIATION... COLD FRONT PUSHING THROUGH HOUSTON AREA THIS MORNING WITH IFR/LIFR CIGS BEHIND THE FRONT. AREA RADAR SHOW BULK OF -RA/RA OVER C TX. EXPECT THIS TO MOVE ACROSS THE NORTHERN HALF OF SE TX DURING THE DAY. THIS SHOULD KEEP CIGS LOW FOR AT LEAST THE NEXT 6-12 HRS BEFORE IMPROVING OVERNIGHT. KCLL/KUTS/KCXO...IFR/LIFR CIGS ALREADY IN PLACE SO WILL KEEP CIGS LOW THROUGH THE NEXT 6-12HRS. EXPECT -RA/RA TO SPREAD OVER THE AREA LATE MORNING THROUGH EARLY AFTERNOON. LIKE HRRR TIMING OF PRECIP BEGIN/END SO TAF REFLECTS THAT TIMING. LOOK FOR MVFR CIGS IN THE AFTERNOON AND HOLDING THROUGH THE NIGHT. LOOKS LIKE VFR CIGS AFTER 12Z THUR. KIAH/KHOU/KSGR...COLD FRONT HAS PUSHED THROUGH KIAH/KSGR BUT JUST AT THE DOOR STEP OF KHOU. GO AHEAD WITH IFR CIGS FOR ALL TERMINALS TO START THE TAF. HAD KDWH REPORT OVC003 SO TEMPO THAT FOR A COUPLE OF HOURS GIVEN THE POSSIBILITY. LIKE HRRR TIMING OF PRECIP BUT REALLY THINK BULK OF -RA/RA WILL BE NORTH OF HOUSTON TERMINALS. WILL STILL CARRY -RA STARTING 16/17Z THROUGH 22Z THIS AFTERNOON. CIGS SHOULD IMPROVE TO MVFR IN THE EARLY AFTERNOON. KLBX/KGLS...COLD FRONT APPROACHING THESE TERMINALS THIS MORNING. EXPECT CIGS TO GO DOWN TO IFR BEHIND THE FRONT LIKE OTHER TERMINALS BUT COULD SEE ONLY MVFR. IFR/MVFR CIGS WILL BE CHALLENGING TO DETERMINE DUE TO THE COAST AND HOW AIRMASS BEHIND THE FRONT MODIFIES DURING THE DAY. WILL MENTION -RA DURING EARLY AFTERNOON BUT THINK MOST OF RAINFALL WILL BE WELL NORTH OF THE COAST. SHOULD SEE CIGS IMPROVE LATE AFTERNOON THROUGH OVERNIGHT. 39 && .PREV DISCUSSION... /ISSUED 508 AM CDT WED OCT 16 2013/ DISCUSSION... THE SOUTHWESTERLY FLOW ALOFT PRESENT EARLY THIS MORNING WAS DUE TO AN UPPER LEVEL HIGH PRESSURE CENTERED OVER THE SOUTHERN GULF AND AN UPPER TROUGH BETWEEN THE WESTERN GREAT LAKES AND THE SOUTHERN ROCKIES. PACIFIC MOISTURE WAS CAUGHT UP IN THE FLOW BUT WAS JUST WEST AND NORTH OF THE FORECAST AREA AT 5 AM. THE MAIN ITEMS OF CONCERN INCLUDE RAIN CHANCES AND TEMPERATURES. THE COLD FRONT WAS PUSHING ACROSS THE CENTRAL AND SOUTHERN COUNTIES EARLY THIS MORNING. THE FRONT SHOULD WORK ITS WAY OFF THE MATAGORDA COAST LATER THIS MORNING AND THEN OFF THE GALVESTON COAST LATER THIS AFTERNOON. MOST OF THE RAINFALL WAS FALLING WELL BEHIND THE FRONT AND AHEAD OF THE 850 MB TROUGH. THE MODELS DO NOT PUSH THE 850 MB TROUGH THROUGH SE TX UNTIL THURSDAY MORNING. DO EXPECT THE MAIN BULK OF THE RAIN TO PUSH INTO THE NORTHWESTERN QUARTER OF THE FORECAST AREA LATER THIS MORNING. THE HIGH PRESSURE IN THE GULF SHOULD ACTUALLY HELP THE RAIN CHANCES DROP OFF OVER THE CENTRAL AND COASTAL AREAS TODAY...ALTHOUGH CHANCES FOR RAIN WILL LINGER OVER THE SOUTHEASTERN HALF OF THE FORECAST AREA TONIGHT AND EARLY THURSDAY AS THE 850 MB TROUGH PUSHES THROUGH. DO NOT EXPECT RAINFALL AMOUNTS TODAY OR TONIGHT TO EXCEED ONE QUARTER TO ONE HALF OF AN INCH ON AVERAGE. THERE IS SOME CONSENSUSFOR A BREAK IN THE RAINY PATTERN THURSDAY AFTERNOON AND EVENING BEFORE ISENTROPIC LIFT HELPS TO RETURN RAIN CHANCES LATE THURSDAY NIGHT AND FRIDAY. THE MODELS THEN PUSH THE COASTAL FRONT EAST OF THE AREA ON SATURDAY WITH SUNDAY LOOKING DRY. BOTH THE GFS AND ECMWF BRING ANOTHER FRONTAL SYSTEM ACROSS SE TX AND RETURN RAIN CHANCES EARLY NEXT WEEK. A PERIOD OF BELOW NORMAL TEMPERATURES ARE EXPECTED THROUGH THE END OF THE WEEK. SOME LOCATIONS NEAR COLLEGE STATION MAY EVEN EXPERIENCE HIGH TEMPERATURES TODAY ALMOST 20 DEGREES BELOW NORMAL. DO EXPECT A WARMUP TO NEAR NORMAL DAYTIME TEMPERATURES TO BEGIN EARLY NEXT WEEK AHEAD OF THE NEXT COLD FRONT. 40 MARINE... COLD FRONT CURRENTLY WORKING THROUGH SE TX THIS MORNING SHOULD PUSH OFF THE COAST THIS EVENING WITH INCREASING NORTHERLY WINDS TONIGHT. MAY NEED SCEC FOR OFFSHORE WATERS BUT WILL BE BODERLINE TO ISSUE AT THIS TIME. SEAS LIKELY REMAIN AROUND 3-4FT WITH 15 KT WINDS. WINDS TURN MORE TO THE EAST FOR THE END OF THE WEEK. MEDIUM RANGE MODELS STILL SHOWING ANOTHER FRONTAL PUSH ON SATURDAY WHICH MAY BE STRONGER. LIKELY SEE SCEC CONDITIONS WITH 4-5FT SEAS OFFSHORE. NE WINDS WILL CONTINUE INTO SUNDAY WITH SEAS REMAINING AROUND 4FT IN OFFSHORE AREAS. 39 AVIATION... COLD FRONT JUST AT THE DOOR STEP OF KCXO AND KDWH. OBS BEHIND THE FRONT SHOWING IFR/LIFR CIGS SO MAY NEED TO UPDATE TAFS FOR CIGS. DO EXPECT SOME RAIN TODAY BUT THINKING IT WILL NOT BE NEARLY AS INTENSE AS PREVIOUSLY THOUGHT. GENERALLY THINK THERE WILL BE PERIODS OF LIGHT RAIN...POSSIBLY AN ISO TSRA BUT THAT LOOKS LESS LIKELY AT THIS POINT. MAIN CONCERN WILL BE HOW LONG IFR CIGS HOLD OVER SE TX BEHIND THE FRONT. 39 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 62 53 73 55 73 / 60 20 10 10 50 HOUSTON (IAH) 74 58 74 56 75 / 60 50 20 10 40 GALVESTON (GLS) 81 65 75 67 76 / 30 50 40 20 30 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...40 AVIATION/MARINE...39
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
233 PM CDT WED OCT 16 2013 .SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT) ISSUED AT 233 PM CDT WED OCT 16 2013 MAIN FORECAST CHALLENGES THROUGH THE SHORT TERM WILL BE... 1. CLOUD TRENDS OVERNIGHT AND IMPACT ON FOG/FROST FORMATION...AND 2. RAIN CHANCES FROM LATE THURSDAY AFTERNOON THROUGH THURSDAY NIGHT. WATER VAPOR IMAGERY COUPLED WITH RAP 500MB ANALYSIS SHOWS AN ELONGATED TROUGH EXTENDING FROM EASTERN ONTARIO CANADA...THROUGH WI/IA/NEB AND CO. STRATUS IS HOLDING STUBBORNLY ACROSS THE AREA AS A RESULT OF THE GENERAL CYCLONIC FLOW ALOFT. TEMPERATURES WERE ALSO SUFFERING AS A RESULT OF THE TROUGH AND CLOUDS...CURRENTLY SITTING IN THE 40S FOR THE MOST PART. FOR TONIGHT...A WEAK RIDGE OF HIGH PRESSURE WILL DRIFT ACROSS THE AREA. AS A RESULT...MODEL CONSENSUS SHOWS FAIRLY GOOD CLEARING/THINNING OF THE STRATUS DECK FROM NORTHWEST TO SOUTHEAST THIS EVENING WITH MOSTLY CLEAR CONDITIONS EXPECTED BY MIDNIGHT. THIS WILL SET UP GOOD RADIATIONAL COOLING...AND WITH A RELATIVELY MOIST LOWER BOUNDARY LAYER...PATCHY FOG IS LIKELY. IN ADDITION... TEMPERATURES ARE EXPECTED TO DIVE INTO THE UPPER 20S/LOWER 30S ALONG AND NORTH OF THE I-94 CORRIDOR FOR AREAS/WIDESPREAD FROST. ELSEWHERE...LOWS TONIGHT ARE EXPECTED TO BE IN THE MID-UPPER 30S...SO CANNOT RULE OUT SOME POCKETS OF FROST. HOWEVER... HEADLINE-ABLE FROST IS NOT EXPECTED. WILL THEN BE WATCHING A MID-LEVEL TROUGH AND SURFACE COLD FRONT DROP SOUTHEAST ACROSS THE AREA LATER THURSDAY AFTERNOON THROUGH THURSDAY NIGHT. NAM/GFS SHOWING FAIRLY DECENT PV-ADVECTION IN THE 700-300MB LAYER ASSOCIATED WITH THIS WAVE FOR A BOUT OF SCATTERED RAIN SHOWER ACTIVITY MOVING INTO AND ACROSS THE AREA. WARM AIR ADVECTION AHEAD OF THE MID-LEVEL WAVE/SURFACE COLD FRONT THURSDAY BRING 925MB TEMPERATURES INTO THE 8-11C RANGE. THIS SHOULD EQUATE TO NEAR SEASONABLE HIGHS IN THE MIDDLE 50S TO AROUND 60 DEGREES. LOWS THURSDAY NIGHT BEHIND THE COLD FRONT ARE EXPECTED TO DROP INTO THE UPPER 30S TO LOWER 40S. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 233 PM CDT WED OCT 16 2013 MAIN CONCERN THROUGH THE LONG TERM IS UNSEASONABLY COLD UPPER LEVEL CYCLONIC FLOW AND PERIODIC SHOTS AT PRECIPITATION. FRIDAY APPEARS TO BE A DRY DAY AS A WEAK MID-LEVEL/SURFACE RIDGE DRIFTS ACROSS THE AREA. HOWEVER...TEMPERATURES WILL BE SOME 5 TO 10 DEGREES BELOW NORMAL WITH HIGHS IN THE 50-55 DEGREE RANGE. FOR SATURDAY...MODELS IN AGREEMENT IN PUSHING ANOTHER DEEP/COLD MID-LEVEL TROUGH OVER THE REGION FOR UNSEASONABLY COOL TEMPERATURES ALONG WITH SCATTERED RAIN SHOWER ACTIVITY GIVEN STEEP 925-700MB LAPSE RATES. LOOK FOR HIGHS IN THE MIDDLE 40S TO THE LOWER 50S. SATURDAY NIGHT INTO SUNDAY LOOKS DRY AT THIS POINT AS ANOTHER WEAK RIDGE OF HIGH PRESSURE DRIFTS OVER THE REGION. PLAN ON LOWS SATURDAY NIGHT IN THE 29-33 DEGREE RANGE WITH HIGHS SUNDAY IN THE MIDDLE 40S TO NEAR THE 50 DEGREE MARK. MODELS THEN DIVERGE A BIT FOR MONDAY THROUGH WEDNESDAY IN HANDLING OF SYSTEMS RIPPLING ACROSS THE AREA IN COLD NORTHWEST FLOW ALOFT. MODEL CONSENSUS GENERALLY YIELDS A 25-35 PERCENT PROBABILITY OF PRECIPITATION THROUGH THE PERIOD. WILL HAVE TO WATCH PRECIPITATION TYPE SUNDAY NIGHT INTO EARLY MONDAY MORNING / MONDAY NIGHT INTO TUESDAY MORNING / AND TUESDAY NIGHT INTO WEDNESDAY MORNING AS TEMPERATURES WILL BE COLD ENOUGH TO SUPPORT AT LEAST A RAIN/SNOW MIX. OTHERWISE...WITH DAYTIME 925MB TEMPERATURES HOVERING IN THE -1 TO -2C RANGE...DAYTIME HIGHS ARE EXPECT TO BE SOME 10-15 DEGREES BELOW NORMAL WITH READINGS IN THE MID 40S TO NEAR 50 MONDAY AND TUESDAY AND IN THE LOWER AND MIDDLE 40S ON WEDNESDAY. OVERNIGHT LOWS ARE EXPECTED TO BE IN THE LOW-MID 30S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1228 PM CDT WED OCT 16 2013 TWO CONCERNS FOR THE AVIATION FORECAST...LINGERING STRATUS AND POTENTIAL FOR FOG TONIGHT...ESPECIALLY AT LSE. STRATUS PERSISTS ACROSS MUCH OF WI...SOUTHEAST MN AND NORTHEAST IA...LINGERING IN THE WAKE OF A TROUGH OF LOW PRESSURE THAT MOVED THROUGH THE TAF SITES LAST NIGHT. THE CLEARING LINE IS JUST APPROACHING MSP AT 17Z...CO-LOCATED JUST EAST OF A SURFACE HIGH PRESSURE RIDGE AXIS. AS THIS RIDGE PUSHES EAST...EXPECTING THE CLEARING TO GO ALONG WITH IT. TIMING THIS CLEARING REMAINS PROBLEMATIC...THOUGH...WITH MODEL GUIDANCE CONTINUING TO DELAY THE CLEARING. THIS MAKES SENSE SO HAVE CLEARING GO THROUGH RST AT 23Z AND LSE AT 03Z. THESE TIMES COULD EVEN BE PUSHED FURTHER BACK A FEW HOURS IF THE SUN DOES NOT MIX OUT MORE OF THE NORTHWEST SIDE OF THE CLOUDS. MVFR CEILINGS ARE ANTICIPATED TO PERSIST WHILE THE STRATUS IS AROUND. ONCE THE STRATUS CLEARS...WINDS WILL GO LIGHT AT LSE AS THE HIGH PRESSURE RIDGE AXIS MOVES IN. THIS SETS POTENTIAL VALLEY FOG. HAVE TRENDED THE FORECAST TOWARDS THIS POTENTIAL WITH A 4SM BR AND SCT003 DECK. HOWEVER...CONCERNS OF CLOUDS MOVING UP FROM THE SOUTH AS WELL AS TIMING THE CLEARING OF THE CURRENT STRATUS PRECLUDES GOING LOWER ON CEILINGS AND VISIBILITIES. ADDITIONALLY...LOW LEVEL WINDS ARE GOING TO INCREASE LATE IN THE NIGHT AHEAD OF A TROUGH DROPPING THROUGH MN...WHICH COULD DISRUPT THE VALLEY FOG/STRATUS PROCESS. THERE COULD ALSO BE SOME MVFR BR AT RST BUT THINK WINDS WILL BE STRONG ENOUGH TO PREVENT IT. VFR CONDITIONS ARE EXPECTED AT BOTH TAF SITES AFTER ANY FOG MIXES OUT IN THE MORNING. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...DAS LONG TERM....DAS AVIATION.....AJ
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
222 AM EDT FRI OCT 18 2013 .PREV DISCUSSION... /ISSUED 731 PM EDT THU OCT 17 2013/ EVENING UPDATE... THE COLD FRONT HAS JUST PUSHED SOUTH OF ATLANTA WITH PATCHY SHOWERS...LIGHT RAIN AND DRIZZLE ALONG AND AHEAD OF THE FRONT... NOW MOSTLY ACROSS CENTRAL GA. NOT SUFFICIENT LIFT NOR INSTABILITY TO WARRANT MENTION OF THUNDER THE REST OF TONIGHT... SO HAVE UPDATED ZONES TO REMOVE THUNDER WORDING. CLOUDS STRETCH WELL BACK INTO TN AND NW AL... SO HAVE TWEAKED CLOUDS TO SHOW A SLOW SCATTERING OVER NORTH GA THIS EVENING AND OVERNIGHT... THEN HELD ONTO MOSTLY CLOUDY SKIES ACROSS MUCH OF CENTRAL GA THROUGH TONIGHT. ADJUSTED POPS TO BETTER ALIGN WITH RADAR TRENDS. OTHERWISE... FORECAST IS ON TRACK WITH SCATTERED SKIES AND COOLER LOWS IN THE 40S STILL EXPECTED TO SPREAD INTO NORTH GA BY MORNING. /39 SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/... /ISSUED AT 344 PM EDT THU OCT 17 2013/ SHORT TERM MODELS IN FAIRLY GOOD AGREEMENT...SHOWING WEAKEN FRONT WASHING OUT AS IT MOVES ACROSS THE FORECAST AREA THIS AFTERNOON AND EVENING. LATEST RAP HAS INITIALIZED AREA OF SHOWERS WELL AND NEAR TERM FORECAST WILL LEAN HEAVILY TOWARD RAP AS SHOWERS DISSIPATE IN THE ATL AREA BY 4-5PM AND OVER THE GVL-AHN AREA BY THIS EVENING. WILL GO AHEAD AND DROP MENTION OF THUNDER FROM FORECAST AS INSTABILITY LIMITED AS WEAK WAVES MOVES ACROSS THE AREA THIS AFTERNOON AND EVENING AND THE SHOWER ACTIVITY IS PUSHING OUT OF FORECAST AREA AS THE SHORTWAVE APPROACHES. MODELS BRINGING DRIER AIR INTO THE AREA THIS EVENING WITH CLEARING SKIES BY MORNING. LATEST SATELLITE SHOWING CLOUDS CONTINUE BACK INTO PORTIONS OF MISSISSIPPI AND EXPECT THAT WHILE THERE WILL BE DRYING WE CAN ALSO EXPECT SOME COOL AREA STRATUS TO DEVELOP AS WELL. WILL COMPROMISE FOR NOW AND SETTLED ON SCATTERING CLOUDS OUT THIS EVENING BUT DID NOT CLEAR THEM OUT ALTOGETHER. BASED UPON HOLDING SOME CLOUDS IN HAVE GONE WARMER THAN GUIDANCE TEMPERATURES BY A DEGREE OR SO OVERNIGHT WITH HIGHS TOMORROW SLIGHTLY WARMER THAN TODAY. ATWELL LONG TERM /SATURDAY THROUGH THURSDAY/... /ISSUED AT 344 PM EDT THU OCT 17 2013/ NO MAJOR CHANGES MADE TO THE EXTENDED FORECAST. MODELS CONSISTENT INDICATING THE COLD FRONT WITH BE SE OF THE FORECAST AREA TO START FRIDAY NIGHT. HOWEVER GFS/NAM/EUROPEAN SOMEWHAT DIFFERENT WITH THE PLACEMENT OF THE DEEPER MOISTURE AXIS THROUGH THE NIGHT. GFS/NAM SIMILAR WITH SPREADING DEEPER MOISTURE BACK OVER MAINLY CENTRAL GA AND THE EUROPEAN IS MORE BROADLY SPREADING MOISTURE ACROSS THE ENTIRE AREA BY NIGHTS END. ALL IN ALL THIS SEEMS TO KEEP BEST SHOWER CHANCES ACROSS MAINLY CENTRAL GA. GFS/NAM KEEPS THE BEST MOISTURE AND SHOWER CHANCES ACROSS CENTRAL GA FOR SATURDAY WHILE THE EUROPEAN SPREADS MOISTURE AND SHOWER CHANCES ACROSS THE ENTIRE AREA. EITHER WAY THE BEST CHANCES FOR SHOWERS WILL BE ACROSS CENTRAL GA AND POSSIBLY PORTIONS OF N GA. THE MOISTURE COMING N DUE MAINLY TO THE APPROACH OF A SHORT WAVE. THE MOISTURE WILL HAVE EXITED ALL BUT THE FAR SE CWA TO START SUNDAY BUT WILL EXIT THAT AREA QUICKLY. SURFACE HIGH PRESSURE MOVES INTO THE ATLANTIC ON MONDAY WHICH BEGINS TO SPREAD MOISTURE INTO THE FAR SE CWA WITH SMALL SHOWER CHANCES ASSOCIATED. A WEAK COLD FRONT MOVES TO THE AREA ON TUESDAY WITH INCREASED SHOWER CHANCES ACROSS THE AREA TUESDAY/TUESDAY NIGHT. SMALL SHOWER CHANCES WILL BE CONFINED TO THE FAR SE CWA TO START THE DAY ON WEDNESDAY BEFORE ENDING. TEMPERATURES WILL BE TRENDING TO A LITTLE BELOW NORMAL FOR MUCH OF THE EXTENDED PERIOD. BDL/01 01 && .AVIATION... 06Z UPDATE... LATEST SURFACE ANALYSIS INDICATES THAT AT LEAST AS FAR AS THE WIND SHIFT IS CONCERNED...COLD FRONT HAS MADE IT THROUGH ALL THE TERMINALS. DRIER AIR MOVING IN IS MUCH DELAYED...ESPECIALLY LOW LEVEL MOISTURE WHICH IS PRODUCING LIFR FOG OVER PORTIONS OF ALABAMA AND TENNESSEE. GUIDANCE SUGGESTS MOST OF THIS WILL REMAIN NORTH OF THE TERMINALS WITH JUST CONTINUED MVFR FOR ATL TAF SITES THROUGH MID MORNING. FOR CSG AND MCN...POTENTIAL IS THERE FOR IFR AND HAVE ADVERTISED IN 06Z SET FOR THE MORNING HOUR. //ATL CONFIDENCE...06Z UPDATE... MEDIUM TO HIGH CONFIDENCE ON ALL ELEMENTS. DEESE && .PRELIMINARY POINT TEMPS/POPS... ATHENS 74 55 72 49 / 5 20 20 10 ATLANTA 73 59 71 49 / 5 10 20 10 BLAIRSVILLE 68 48 72 42 / 5 5 10 5 CARTERSVILLE 72 52 75 45 / 5 5 10 5 COLUMBUS 79 61 74 51 / 10 30 30 10 GAINESVILLE 69 56 74 48 / 5 5 20 5 MACON 77 61 74 51 / 10 40 30 10 ROME 73 50 75 43 / 5 5 10 5 PEACHTREE CITY 73 54 72 46 / 5 10 20 10 VIDALIA 82 65 77 59 / 30 50 30 30 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...DEESE LONG TERM....20 AVIATION...DEESE
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
408 AM CDT Fri Oct 18 2013 .SHORT TERM...(Today through Sunday Night) Issued at 405 AM CDT FRI OCT 18 2013 Long wave troughing persisted across the central CONUS early this morning, and this pattern appears locked in for the next couple of weeks. Embedded within the the large scale dip, the third in a recent sequence of shortwave impulses was tracking southward through Wyoming, and remains on track to target the southern half of the CWA later today. Front Range, CO radar shows an impressive band of snow expanding over NE Colorado, while satellite imagery shows mid cloud rapidly expanding eastward across srn Nebraska and most of Kansas. These trends suggest that the axis of strong elevated frontogenesis will likely come in a bit further north than earlier progged. This is supported by a northward shift in the 00Z model solutions and more recently the hourly RAP output. For today, cloud cover will quickly overspread the CWA from west to east this morning. Forecast soundings and model cross sections show a rapid top- down saturation as sloped 700-500mb frontogenesis increases in response to large scale height falls isentropic ascent. Despite clear skies presently, precipitation could begin over ern KS/west central MO as early noon. As discussed yesterday, the sub- cloud layer will initially be very dry while 850-700mb temperatures fall sharply as the shortwave approaches. In fact, if not for the boundary layer, we would likely be dealing with wet snow! Nonetheless, once the rain begins, surface temps will immediately respond to diabatic cooling and fall back through the 40s. Hourly temperatures reflect a non-diurnal curve for the afternoon. Precipitation should reach a local maximum between 18-00Z, steadily shifting southward with time as a small 700-500mb jet streak develops and shifts the axis of greatest mid level forcing. QPF amounts will average between one and two tenths of an inch, generally along and south of I-70. The mid level trough axis will quickly pivot across the CWA overnight, with skies gradually clearing from west to east. Temps will fall into the mid 30s by daybreak, and although conditions are not optimal for a widespread frost, the moist boundary layer and diminishing winds could enhance the potential. Next shift may want to consider headlines for all or portions of the region tonight. After a chilly day Saturday, strengthening west winds will develop south of a progressive shortwave trough moving across the Upper Midwest. Strong low level warm advection will begin Saturday night and continue into Sunday, with a deep layer Chinook component expected to rapidly spread some mild air eastward across the Plains. Given upward trends in 850mb temp progs, have bumped highs into the upper 60s to around 70 for Sunday, and made a significant increase to the surface winds/gusts over the srn half of the CWA. A dry cold front will sweep across the area Sunday night, leading to a very challenging low temperature forecast that hinges entirely on where the front ends up by 8AM. Current forecast projects a near 15 degree gradient from mid 30s along the Iowa border to near 50 across mid Missouri, and significant adjustments remain possible. .LONG TERM...(Monday through Thursday) Issued at 403 AM CDT FRI OCT 18 2013 Later half of the forecast will continue the cool trend as negative height anomalies persist across the Lower Missouri River Valley through much of next week. As Monday arrives a significant trough will be digging in across the center of the nation providing cold air from the Canadian Plains with plenty of opportunity to rush south through the northern and central Plains. Resulting cold air with the northwest flow will keep temperatures ranging below normal through the week. This is supported by 850mb model output which advertises subzero centigrade temperatures sweeping into the region Monday, and again Wednesday behind a small shortwave trough zipping through the flow. This should make for some cool fall conditions next week with highs only the 50s expected Monday through Wednesday. As for overnight low, a bit of a frost might be in the offing. Overnight lows will drop into the 30s Tuesday, Wednesday and Thursday mornings. Currently, areas along and north of highway 36 look to have the greatest chance for seeing repeated frost. Otherwise, have included a silent slight chance for showers Wednesday into Thursday. Models continue to advertise a shortwave trough zipping through the northwest flow mid-week, providing a little reinforcing shot of cold air for Thursday mornings lows. Models might be over doing the amount of moisture, thus confusing low cloud cover with QPF, though disturbances in the northwest flow often squeeze some light precipitation out across eastern Kansas or Missouri. Have left the silent slight chance POPs characterized as showers for now, though if confidence in Tuesdays quick shortwave improves some consideration might be needed for including snow in the precipitation forecast. && .AVIATION...(For the 06Z TAFS through 06Z Friday Night) Issued at 1130 PM CDT THU OCT 17 2013 Evening data packages show good continuity from previous model runs and continue to spread an area of rain eastward across KS reaching into west central MO around the noon hour. Best rain chances will be along and south of the MO River with a high confidence of this occurring. Made only minor changes on timing of rain into the KC terminals with KSTJ remaining dry. Still anticipate a lowering of VFR ceilings although the northern edge of MVFR ceilings could reach as far north as KMKC. Won`t be able to make that decision until the rain band sets up Friday morning. Otherwise, after the rain exits west central MO by late afternoon only expect VFR conditions with winds switching to the southwest ahead of a fast moving surface trough. Could see some light rain move into northwest MO Friday evening but not affect the terminals. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ SHORT TERM...Bookbinder LONG TERM...Cutter AVIATION...MJ
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
324 AM CDT Fri Oct 18 2013 .SHORT TERM: (Through Late This Afternoon) Issued at 320 AM CDT Fri Oct 18 2013 A weak cold front was moving through the region early this morning, but its only effect across the LSX CWA will be a wind shift from southwest to northwest after fropa. Early morning water vapor imagery along with recent RAP analyses of the 1.5 PVU surface both depict a positively tilted trough over the central CONUS with a couple of stout disturbances sliding down the western side of the trough. Increasing large scale ascent ahead of these vorticity centers will support scattered rain showers from this afternoon into tonight. Since it may take some time to saturate the initially dry air mass, precipitation chances look higher after 19/00z compared to earlier in the afternoon. Kanofsky .LONG TERM: (Tonight through Thursday) Issued at 320 AM CDT Fri Oct 18 2013 Precipitation threat overnight is expected to transition from very light showers during the early evening attempting to stream east- northeast from mid MO, to a broader area of rain developing over the southeast half of the CWA during the overnight hours as upstream shortwave begins to push into mid Mississippi Valley and the large scale ascent is realized over the CWA. Believe the NAM is too far southeast with its QPF in the 06-12z time frame, as almost all over solutions have northern fringes of QPF north of STL. While specifics may be a bit off, the 3 hourly PoP trends from the 03z SREF look very reasonable. This rain should wind down late tonight or very early Saturday morning over our southeast counties as shortwave exits to the east. The brief cool-down in the wake of this feature will quickly give way to WAA in advance of the next shortwave from late Saturday afternoon, with fairly strong warming forecast over most of the CWA from late Saturday night into Sunday. By Sunday afternoon all short range models are forecasting at least 8C 850mb temps over the CWA, with thermal ridge extending from southeast Kansas into ne MO possibly pushing temps to around 10C. Given this trend have upped temps about a category from going forecasts, and most areas should push the 70 degree mark. Heading into the medium range, upper level trof is forecast to deepen over the eastern CONUS in the wake of the aforementioned shortwave, and this will bring even colder air into the region for the start of the new week. The airmass that pushes into the area Monday night and Tuesday will be the coldest so far of this fall, and its certainly possible that the growing season could come to an end in some areas either Tuesday or Wednesady morning. However, the frost threat will depend on timing of surface ridge and any clouds that advect into the region on the fairly dirty northwest flow, and specifics with both the high and clouds are not clear at this time. Based on progged 850mb temps it appears that during the Tuesday-Thursday time frame highs will only be in the 50s with lows in the 30s. At this time have kept PoPs in the slight chance range with the passage of the cold front Sunday night and Monday due to very limited moisture. Have also continued slight chance PoPs over the area on Tuesday night as another weak shortwave drops into the area. Truett && .AVIATION: (For the 06z TAFs through 06z Friday Night) Issued at 1140 PM CDT Thu Oct 17 2013 VFR conditions will prevail thru the valid TAF period for most of the sites. Exception is expected to be in KUIN where band of post- frontal MVFR CIGs will affect the terminal late tonight and early Friday morning. Otherwise, cold front over central IA and NW MO will move thru the forecast area dry late tonight but will veer surface winds from SW to W-NW. An approaching upper level disturbance on Friday will result in increasing clouds in the afternoon with light rain by late evening. Specifics for KSTL: VFR conditions to prevail thru the valid period. Surface winds will veer early Friday morning with a cold front, expected to move thru dry, but will see clouds and rain chances increase with approaching upper level disturbance late Friday. Clouds and rain anticipated to exit before sunrise Saturday morning. TES && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1137 PM CDT THU OCT 17 2013 .AVIATION...06Z TAFS FOR KOMA...KLNK AND KOFK. VFR CONDITIONS THROUGH THE PERIOD MID BROKEN MID DECK CLOUDS. COULD SEE A FEW SPRINKLES AT ALL 3 TAF SITES...BY 22Z AT KOFK/KLNK AND 01Z AT KOMA. DEWALD && .PREV DISCUSSION... /ISSUED 636 PM CDT THU OCT 17 2013/ AVIATION...00Z TAFS FOR KOMA...KLNK AND KOFK. MVFR CONDITIONS PREVAIL EARLY IN THE TAF PERIOD...AND BIG QUESTION IS WHETHER THESE LOWER CLOUDS WILL SCATTER OUT AS SURFACE HIGH PRESSURE CONTINUES TO BUILD IN FROM THE WEST. OVERALL LOW CONFIDENCE ON TIMING...BUT HAVE FORECAST 05Z...AND WILL ADJUST AS NECESSARY IF CLOUDS DON`T SHOW ANY SIGNS OF BREAKING. PREV DISCUSSION... /ISSUED 322 PM CDT THU OCT 17 2013/ SHORT TERM...TONIGHT THROUGH SUNDAY. NORTHWESTERLY FLOW WITH A SERIES OF EMBEDDED WAVES WILL PREVAIL OVER FORECAST AREA THROUGH THE WEEKEND WITH SOME WARMING EXPECTED. FOR TONIGHT...FIRST IN SEVERAL WAVES WILL BE TRACKING FM DAKOTAS INTO MINNESOTA SPREADING CLOUDS ACROSS AREA INTO EARLY TONIGHT BEFORE PROBABLY DECREASING AFT 06Z. 18Z RAP AND 12Z 4KM WRF AND SOME HOP WRF MEMBERS SUGGESTED SOME VERY LIGHT PRECIP COULD CLIP NERN ZONES EARLY. ANOTHER WAVE MOVING TOWARD KS BY MORNING COULD SPREAD SOME MID/HIGH CLOUDS TOWARD SRN AND ESPECIALLY SWRN ZONES BY MORNING. THE VARIABLE CLOUDS...SOME WIND AND INITIALLY MODEST DWPTS WL LEAD TO KEEPING MOST LOWS A BIT ABOVE GUIDANCE. LITTLE CHANGE TO FRIDAY...KEPT IN SMALL POPS EXTREME SOUTH DUE TO SRN WAVE...ALTHOUGH APPEARS BULK OF ANY PRECIP COULD REMAIN TO OUR SOUTH. ALSO SHARP MID LVL TROUGH AXIS MOVING INTO ERN NEBRASKA TOWARD 00Z COULD ALLOW SOME SHOWER DEVELOPMENT AS H5 TEMPS IN MINUS UPPER 20S C MOVE OVER AREA. SPREAD SMALL CHANCES A BIT FARTHER S. SOMEWHAT DISCOUNTED NAM IN DOWNSLOPE MOISTURE LACKING FLOW BUT THIS COULD FACILITATE FUTURE CHANGES. DID TRIM TEMPS BACK A FEW DEGREES DUE TO EXPECTED CLOUDS...BUT KEPT THEM ON HIGH SIDE OF GUIDANCE. AFTER TROUGH PASSES FRIDAY TEMPERATURES SHOULD BE WARMING SATURDAY AND SUNDAY AHEAD OF A STRONGER WAVE THAT WILL ARRIVE LATE SUNDAY. KEPT FORECAST DRY IN WARM ADVECTION AHEAD OF THIS WAVE...BUT CAN NOT RULE OUT SOME NEED IN LATER FORECASTS. TRENDED MOST MAX TEMPERATURES UPWARD BOTH DAYS TO REFLECT FORECAST H85 TEMPS...BUT DIDN/T MIX TO THAT DEPTH DUE TO POSSIBLE CLOUDS. CHERMOK LONG TERM...SUNDAY NIGHT THROUGH THURSDAY. THE REGION WILL REMAIN IN NORTHWEST FLOW ALOFT AS A BROAD TROUGH REMAINS IN PLACE TO OUR EAST WHILE AN AMPLIFIED RIDGE REMAINS OVER THE WESTERN STATES. THIS WILL ALLOW A COLD CANADIAN AIRMASS TO DROP INTO THE NORTHERN PLAINS AND UPPER MIDWEST. THERE CONTINUES TO BE SOME DISAGREEMENT AS TO HOW FAR WEST THE COLD AIRMASS WILL REACH...HOWEVER THE TREND CONTINUES TO BE COLD FOR NEXT WEEK WITH HIGHS IN THE LOW 50S AND LOWS IN THE LOWER TO MID 30S. SOME WEAK RECOVERY BY THURSDAY MAY BRING HIGHS UP INTO THE MID TO UPPER 50S. KERN && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
330 AM MDT FRI OCT 18 2013 .DISCUSSION... SFC LOW/TROUGH ACROSS FAR EAST CENTRAL NM AND INTO THE ADJACENT PORTION OF TX HAS CIRCULATED LOW LEVEL MOISTURE INTO SE NM WITH ATTENDANT LOW CLOUDS/FOG OVER LEA/EDDY AND SE ROOSEVELT COUNTIES...WHICH IS FARTHER WEST THAN WAS INDICATED 24 HRS AGO. EXPECT THIS WILL MAKE A LITTLE MORE PROGRESS NORTH AND WWD BEFORE THE COLD FRONT...CURRENTLY FROM CAO TO RTN...AND WITH IT/S STRATUS...PUSHES FARTHER SOUTH. RUC INDICATES THE MOISTURE IN THE SOUTHEAST SHOULD EXIT BY MID MORNING WHILE THE STRATUS CONTINUES TO INVADE THE NE AND TO SOME EXTENT THE EAST CENTRAL. TODAY/S AREAL COVERAGE OF POPS DIDN/T CHANGE MUCH FROM PREVIOUS MODEL RUNS. FORECAST HIGHS HOWEVER DID COOL SEVERAL DEGREES IN THE NORTHEAST AND EAST CENTRAL NO DOUBT IN PART TO THE EXTENSIVE LOW CLOUDS THAT MAY LINGER THROUGH EARLY/MID AFTERNOON ACCORDING TO THE RUC. THE AREA FROM RATON TO CLAYTON MAY NOT GET ANY WARMER THAN MID 40S...WHICH IS 20 TO 25 DEGREES BELOW NORMAL IF THE GUIDANCE IS CLOSE. OVERALL HIGHS TODAY RANGE FROM NEAR NORMAL FAR SOUTHWEST TO 10 TO 15 DEGREES BELOW AVERAGE FAR NORTHWEST TO THE FAR SOUTHEAST. THE COOLER THAN AVERAGE HIGHS SET THE STAGE FOR POTENTIAL FOR NEAR TO BELOW FREEZING LOWS TONIGHT. GUIDANCE FOR PORTIONS OF THE EAST CENTRAL CLOSER TO THE TX BORDER AND ROW AREAS HAS COOLED A COUPLE MORE DEGREES...SO A FREEZE WATCH WILL BE ISSUED. SOME LOW LEVEL MOISTURE MAY BE PARKED ALONG THE EAST SLOPES OF THE CENTRAL MT CHAIN THIS EVENING BUT DEWPOINTS STILL EVENTUALLY LOWER SUFFICIENTLY FOR THE THREAT OF A FREEZE. MODELS NOW INDICATE AT LEAST SOME POTENTIAL FOR AN EAST WIND TO BREAK INTO THE MIDDLE RGV THIS EVENING...WHICH COMPLICATES A FREEZE/NO FREEZE DECISION THAT MUCH MORE ESPECIALLY IN THE ABQ METRO. CURRENT THOUGHTS ARE THE WIND COULD DIMINISH AFTER MIDNIGHT...SO DECIDED TO ISSUE A FREEZE WATCH FOR THE MIDDLE AND LOWER RGV AS WELL AS FOR THE UPPER TULAROSA VALLEY...WHERE SOME LOCALES HAVE NOT YET FROZEN. FOR THE REST OF THE WEEKEND...A WARMING TREND WILL COMMENCE WITH HIGHS ACHIEVING NEAR NORMAL STATUS SUNDAY. ANOTHER FRONT COULD ARRIVE IN THE EASTERN PLAINS AS SOON AS LATE SUNDAY...SO HIGHS WILL BE KNOCKED DOWNWARD MONDAY. THIS FRONT LOOKS MORE LIKELY TO PRODUCE AN EAST WIND INTO THE RGV EARLY MONDAY. EXTENDED FORECAST MODEL TRENDS FOR MID TO LATE NEXT WEEK LEAN TOWARDS MORE OF A RIDGE OVER NEW MEXICO. LATEST ECMWF DEPICTS A DECENT SFC HIGH INVADING ERN NM DESPITE THE RIDGE WHILE THE GFS LOCATES IT WELL TO THE EAST...WREAKING HAVOC ON FORECAST TEMPERATURE DECISIONS. BOTH GFS AND ECMWF INDICATE A WEAK DISTURBANCE TRACKING INTO WRN NM FROM THE WEST AROUND THURSDAY OF NEXT WEEK...NOT CONFIDENT AT ALL IT WILL AMOUNT TO MUCH. IN ANY CASE WENT CLOSER TO THE ECMWF SOLUTION FOR TEMPS AND WITH A GFS/ECMWF BLEND FOR POPS. && .FIRE WEATHER... COOLER AIR WILL INVADE NEW MEXICO TODAY AS NORTHWEST FLOW ALOFT DRAGS A TROUGH INTO THE STATE ALONG WITH A BACK DOOR SURFACE FRONT. THE PLAINS WILL OBSERVE THE SHARPEST TEMPERATURE DIFFERENTIAL FROM YESTERDAY ALONG WITH GUSTY NORTHEAST WINDS THROUGH THE DAY AS THE FRONT SPILLS IN. THE CENTRAL TO WESTERN ZONES WILL ALSO BECOME BREEZY TO WINDY WITH A NORTHWESTERLY DIRECTION. SURFACE GRADIENT APPEARS A BIT STRONGER THAN PREVIOUS MODEL RUNS WERE ADVERTISING...SO FORECAST SPEEDS WERE INCREASED TO REFLECT THIS. VENTILATION RATES LOOK TO REMAIN GOOD TO EXCELLENT WITH THESE STRONGER BOUNDARY LAYER BREEZES...BUT WINDS DO NOT APPEAR TO BE CRITICALLY HIGH. DEWPOINTS DROP INTO THE LOWER TEENS AND SINGLE DIGITS IN THE WEST CENTRAL TO SOUTHWESTERN ZONES OF THE FORECAST AREA THIS AFTERNOON...DROPPING MINIMUM RH TO 12 TO 15 PERCENT. THIS AREA OF CRITICALLY LOW RH WILL NOT BE JUXTAPOSED OVER THE AREA WHERE THE STRONGEST WINDS WILL BE...AND THE COOLER TEMPERATURE REGIME DOES NOT FIT INTO THE MOLD OF A CRITICAL FIRE WEATHER EVENT EITHER. MAX TEMPERATURES WILL RUN ABOUT 8 TO 20 DEGREES BELOW NORMAL IN MOST AREAS TODAY. BETTER RH RECOVERY IS EXPECTED TONIGHT WITH COOLER TEMPERATURES. DEWPOINTS MAY LOWER A BIT IN THE PLAINS BY TONIGHT...BUT THEY WILL ACTUALLY RISE A BIT IN THE CENTRAL AREAS OF THE STATE. THIS WILL ALLOW MOST OF THE NORTHERN AND EASTERN TIERS OF THE STATE TO OBSERVE EXCELLENT RH RECOVERY WHILE CENTRAL TO WESTERN ZONES STAY IN THE FAIR TO GOOD CATEGORIES. ANOTHER SIGNIFICANT ASPECT OF TONIGHT/S FORECAST WILL BE THE POTENTIAL FOR FREEZING TEMPERATURES IN MUCH OF THE EAST CENTRAL PLAINS WHERE THE FREEZING MARK HAS YET TO BE REACHED. THIS WILL EXACERBATE FINE FUEL CURING. THERE WILL ALSO BE POTENTIAL FOR FREEZING TEMPERATURES ALONG THE MIDDLE RIO GRANDE AND TULAROSA VALLEYS...PRIMARILY IN THE LOWEST ELEVATIONS. SOME OF THESE VALLEY AREAS HAVE FLIRTED WITH FREEZING ON A COUPLE OF OCCASIONS THIS SEASON...BUT A WIDESPREAD HARD FREEZE HAS STILL NOT HAPPENED. NORTHWEST FLOW WILL NOT BE AS STRONG ON SATURDAY...AND ONLY SOME ISOLATED BREEZY TO WINDY CONDITIONS ARE EXPECTED OVER THE CENTRAL HIGHLANDS. TEMPERATURES WILL WARM A FEW DEGREES IN MOST OF THE FORECAST AREA AND SEVERAL DEGREES IN THE NORTHEASTERN PLAINS...BUT STILL DAYTIME HIGHS IN ALL AREAS WILL FALL JUST SHY OF CLIMATOLOGY. LOWEST DEWPOINTS WILL STAY CONFINED TO WEST CENTRAL NM SATURDAY...BUT THESE WILL MIX AND ADVANCE EASTWARD INTO SUNDAY. THIS WILL SPREAD SOME CRITICAL RH OVER THE CENTRAL HIGHLANDS WHERE A BRIEF BOUT OF CRITICAL WINDS WILL ALSO DEVELOP SUNDAY AFTERNOON. THE NEXT COLD FRONT WILL ARRIVE SUNDAY NIGHT AND INTO MONDAY MORNING. THIS BOUNDARY WILL LIKELY ADVANCE BEYOND THE CENTRAL MOUNTAIN CHAIN AND INTO THE RIO GRANDE VALLEY...PRODUCING SOME GUSTY WINDS ALONG THE BOUNDARY AND THROUGH CENTRAL GAPS/CANYONS WHILE TEMPERATURES PLUMMET BACK BELOW AVERAGE. OVERALL A DRIER AND MORE TRANQUIL PATTERN IS EXPECTED THROUGH TUESDAY AND WEDNESDAY OF NEXT WEEK...HOWEVER THERE IS SOME UNCERTAINTY REGARDING ANOTHER POTENTIAL FRONT. FORECAST MODELS HAVE DIFFERING NOTIONS ON HOW THE UPPER RIDGE WILL BREAK DOWN...AND MODELS HISTORICALLY HAVE SOME NOTORIOUS DEFICIENCIES IN THESE HIGH AMPLITUDE PATTERNS. 52 && .AVIATION... 06Z TAF CYCLE VFR CONDITIONS SHOULD PREVAIL THROUGH THE NEXT 24 HOURS AT ALL TAF SITES. BACK DOOR COLD FRONT IN FAR NE NOW WILL DROP SOUTH AND WEST OVERNIGHT INTO FRIDAY. HAVE A WIND SHIFT IN KTCC AT 12Z FRIDAY AND KROW AT 15Z FRIDAY. LOW CLOUDS...BKN030...ALREADY FORMING AROUND CAO AND COULD IMPACT TCC LATER TONIGHT. NOT ENOUGH CONFIDENCE TO PUT IN THE TAF THOUGH. GOOD CHANCE SE WIND AT SAF SAF FROM 01Z TO 06Z FRIDAY EVENING AND BRIEF E WIND POSSIBLE IN ABQ BETWEEN 02Z AND 06Z...PUT IN TEMPO GROUP FOR ABQ. && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 58 26 61 30 / 0 0 0 0 DULCE........................... 55 21 59 24 / 0 0 0 0 CUBA............................ 55 24 58 27 / 0 0 0 0 GALLUP.......................... 58 17 62 22 / 0 0 0 0 EL MORRO........................ 56 18 60 24 / 0 0 0 0 GRANTS.......................... 59 20 62 26 / 0 0 0 0 QUEMADO......................... 60 23 65 29 / 0 0 0 0 GLENWOOD........................ 70 30 71 35 / 0 0 0 0 CHAMA........................... 49 18 54 19 / 0 0 5 5 LOS ALAMOS...................... 55 26 59 29 / 0 0 0 0 PECOS........................... 53 26 59 29 / 5 5 5 0 CERRO/QUESTA.................... 50 17 56 19 / 5 5 5 5 RED RIVER....................... 43 17 48 23 / 10 5 5 5 ANGEL FIRE...................... 47 18 55 20 / 10 5 5 5 TAOS............................ 52 18 58 22 / 5 5 0 0 MORA............................ 50 21 59 26 / 5 5 5 5 ESPANOLA........................ 59 24 62 28 / 0 0 0 0 SANTA FE........................ 56 25 59 29 / 0 0 0 0 SANTA FE AIRPORT................ 58 27 61 32 / 0 0 0 0 ALBUQUERQUE FOOTHILLS........... 59 31 59 36 / 0 0 0 0 ALBUQUERQUE HEIGHTS............. 62 35 62 40 / 0 0 0 0 ALBUQUERQUE VALLEY.............. 64 29 63 37 / 0 0 0 0 ALBUQUERQUE WEST MESA........... 63 33 63 38 / 0 0 0 0 LOS LUNAS....................... 66 34 66 39 / 0 0 0 0 RIO RANCHO...................... 62 34 62 40 / 0 0 0 0 SOCORRO......................... 68 37 67 41 / 0 0 0 0 SANDIA PARK/CEDAR CREST......... 60 28 57 34 / 0 0 5 0 TIJERAS......................... 61 29 59 34 / 0 0 0 0 MORIARTY/ESTANCIA............... 59 27 61 31 / 0 0 5 0 CLINES CORNERS.................. 56 29 59 34 / 5 5 5 0 GRAN QUIVIRA.................... 61 29 62 34 / 0 5 5 0 CARRIZOZO....................... 66 32 64 36 / 0 0 0 0 RUIDOSO......................... 60 36 59 41 / 0 5 5 0 CAPULIN......................... 43 19 59 26 / 20 5 5 5 RATON........................... 46 21 62 28 / 20 5 5 5 SPRINGER........................ 50 22 62 30 / 10 5 5 5 LAS VEGAS....................... 51 23 62 32 / 5 5 5 5 CLAYTON......................... 44 30 65 36 / 20 5 5 5 ROY............................. 50 28 62 36 / 5 5 5 5 CONCHAS......................... 55 30 66 34 / 5 5 5 5 SANTA ROSA...................... 56 30 69 36 / 0 5 5 5 TUCUMCARI....................... 54 30 69 37 / 5 5 5 5 CLOVIS.......................... 55 30 64 37 / 5 5 5 5 PORTALES........................ 58 31 65 38 / 5 5 5 5 FORT SUMNER..................... 61 32 67 38 / 0 5 5 5 ROSWELL......................... 73 36 68 43 / 0 5 5 0 PICACHO......................... 69 33 67 39 / 0 5 5 0 ELK............................. 66 33 65 38 / 0 5 5 0 && .ABQ WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR THE FOLLOWING ZONES...NMZ519-520-525-533>538. && $$
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1134 PM CDT THU OCT 17 2013 .AVIATION... EXPECT RAPIDLY DETERIORATING CONDITIONS AT LBB SHORTLY AFTER MIDNIGHT AS LOW CIGS AND EVENTUALLY SOME DENSE FOG EMERGE IN A VERY MOIST UPSLOPE REGIME. HAVE ALREADY NOTICED FEW CLOUDS AROUND 1500 FT AT LBB WITH LIGHT FOG REPORTED AT PVW. SATELLITE SHOWS A DENSE LAYER OF MVFR AND IFR CIGS NEAR MIDLAND THAT WILL EXPAND NORTH THROUGH THE NIGHT...SO OVERALL THIS PATTERN FAVORS IFR/LIFR CIGS WITH OCCASIONAL DENSE FOG AND DRIZZLE ON THE CAPROCK. CDS WILL FARE COMPARABLY BETTER WITH PREDOMINANTLY MVFR CIGS FOR THE BETTER PART OF THE DAY. WE STILL EXPECT VFR CONDS TO RETURN TO LBB AROUND 18Z OR SO ONCE MOIST SOUTH WINDS VEER WESTERLY AHEAD OF A COLD FRONT. BUMPED FROPA TIME BACK A TOUCH AT BOTH LBB AND CDS...BUT STILL KEPT NLY GUSTS AROUND 30 KNOTS FOR MID-TO-LATE AFTERNOON. OUTSIDE OF A STRAY SHRA BEHIND THE FRONT NEAR CDS...PRECIP WILL BE LIMITED. && .PREV DISCUSSION... /ISSUED 932 PM CDT THU OCT 17 2013/ UPDATE... UPDATED TO BOOST LOW CLOUD COVERAGE AFTER MIDNIGHT AND ALSO TO ADD MENTION OF FOG AND DRIZZLE ON THE CAPROCK EARLY FRI MORNING. THE 02Z SURFACE PATTERN PAINTS A PRETTY CLASSIC PICTURE FOR SUCH A SCENARIO LATER TONIGHT AS DEWPOINTS IN THE PERMIAN BASIN ARE ALREADY PUSHING 60 DEGREES WITH TEMPS ON THE SOUTH PLAINS IN THE MID AND UPPER 50S. LATEST NAM AND RECENT RUNS OF THE RAP ARE CONSISTENT IN BREAKING OUT STRATUS AROUND 09Z ACROSS MUCH OF THE CAPROCK AND WESTERN PERMIAN BASIN...A BIT SIMILAR TO WHAT WE SAW LAST NIGHT IN SERN NEW MEXICO. MODEL SOUNDINGS SHOW SUFFICIENTLY THICK STRATUS HERE FOR DRIZZLE BY 12Z AND THIS IS REFLECTED BY THE NAM`S SPOTTY LIGHT QPF. DENSE FOG POTENTIAL IS A BIT LESS CERTAIN...BUT THIS WILL BE REVISITED BY THE MIDNIGHT SHIFT. ALSO REMOVED SHOWER MENTION ON THE CAPROCK FROM 12-17Z FRI AS DRIZZLE WOULD BE THE MOST WE CAN SQUEEZE OUT BEFORE THE COLD FRONT AND A BRIEF WINDOW FOR SHOWERS DEVELOP EARLY IN THE AFTERNOON JUST BEHIND THE FRONT. GIVEN MILD LOWS AND MOIST ADVECTION...RAISED OVERNIGHT LOWS SEVERAL DEGREES ON THE CAPROCK WHILE KEEPING AREAS FARTHER EAST INTACT IN LIGHT OF DRIER AIR CHARACTERIZED BY DEWPOINTS IN THE LOW/MID 40S. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 38 55 28 64 39 / 10 10 0 0 0 TULIA 47 53 32 65 41 / 10 20 10 0 0 PLAINVIEW 48 57 32 65 41 / 10 20 10 0 0 LEVELLAND 49 61 33 66 41 / 10 10 10 0 0 LUBBOCK 50 58 34 65 42 / 10 20 10 0 0 DENVER CITY 51 64 35 65 43 / 0 10 10 10 0 BROWNFIELD 52 63 35 65 43 / 10 10 10 0 0 CHILDRESS 51 56 36 69 44 / 20 30 20 0 0 SPUR 50 63 37 67 44 / 10 20 20 10 0 ASPERMONT 51 66 38 67 45 / 10 30 20 10 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 93
AREA FORECAST DISCUSSION
NWS PUEBLO CO
734 AM MDT FRI OCT 18 2013 .UPDATE... ISSUED AT 732 AM MDT FRI OCT 18 2013 UPDATED FRONT END OF FORECASTS TO REFLECT CURRENT OBSERVATIONS AND TRENDS. NO MAJOR CHANGES TO FORECAST AT THIS TIME. LW && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 527 AM MDT FRI OCT 18 2013 ...HIT AND RUN STORM ON THE WAY... IT`S ON OUR DOORSTEP. THE SHORTWAVE THAT HAS BEEN HEADED OUR WAY IS ABOUT TO ARRIVE. MULTIPLE LATE NIGHT TWEETS INDICATE SNOW HAS SPREAD QUICKLY SOUTH ACROSS THE NORTHERN FRONT RANGE URBAN CORRIDOR AND NORTHEAST PLAINS THIS MORNING. RADAR AND SURFACE REPORTS INDICATE THAT SNOW HAS ALREADY SPREAD INTO THE CENTRAL MOUNTAINS...INCLUDING LEADVILLE AND MONARCH PASS...AND IT IS JUST NOW CROSSING THE PALMER DIVIDE INTO NORTHERN TELLER AND NORTHERN EL PASO COUNTIES. ALL FORECAST MODELS AGREE THAT SNOW WILL MOVE INTO TELLER AND EL PASO COUNTIES THIS MORNING...WITH A MIXTURE OF RAIN AND SNOW SHOWERS SPREADING SOUTH ACROSS THE REST OF THE EASTERN MOUNTAINS AND PLAINS. THE GFS...AND TO A LESSER EXTENT...THE NAM HAVE BEEN GRADUALLY TRENDING BACK TOWARD BETTER CHANCES FOR PRECIPITATION OVER THE EASTERN MOUNTAINS AND PLAINS THAN THEY WERE 24 HOURS AGO. ADDITIONALLY...SHORT RANGE FORECASTS OFF OF THE HIGH RESOLUTION MODELS...INCLUDING THE HRRR AND THE WRF...ALSO SHOW AT LEAST SOME PRECIPITATION SPREADING SOUTH ACROSS MOST OF THE EASTERN MOUNTAINS AND PLAINS THIS MORNING. NONE OF THE MODELS HAVE ANYTHING VERY HEAVY...BUT THEY DO HAVE SOME LIGHT TO LOCALLY MODERATE AMOUNTS. RIGHT NOW...BEST BET IS FOR 1 TO 3 INCHES OF SNOW OVER THE CENTRAL MOUNTAINS AND PIKES PEAK...LOCAL 1 TO 2 INCHES AMOUNTS ACROSS TELLER AND EL PASO COUNTIES...AND GENERALLY AN INCH OR LESS ACROSS THE REST OF THE EASTERN MOUNTAINS AND PLAINS. PRECIP BELOW 5500 FEET WILL PROBABLY COME AS A MIXTURE OF RAIN AND SNOW SHOWERS...WHICH SHOULD HELP TO LIMIT ACCUMULATIONS. ELEVATIONS ABOVE 5500 FEET WILL SEE MOSTLY SNOW AND THE BEST CHANCES FOR ACCUMULATION. SECOND ONLY TO THE PIKES PEAK REGION...THE FAR EASTERN PLAINS ALONG THE KANSAS BORDER WILL SEE SOME OF THE BETTER ODDS FOR PRECIPITATION TODAY. LIGHT SNOW IS ALREADY FALLING AT BURLINGTON AND RADAR SHOWS DEVELOPING PRECIPITATION OVER NORTHEAST KIOWA COUNTY AT THIS TIME. THIS DEVELOPMENT SHOULD CONTINUE SOUTHWARD THROUGH THE MORNING INTO THE EARLY AFTERNOON HOURS. TEMPERATURES WILL BE A BIT BORDERLINE FOR MUCH IN THE WAY OF SNOW ACCUMULATION...BUT COULD BE SOME SPOTTY LIGHT AMOUNTS...ESPECIALLY ON GRASSY AREAS. EVERYTHING SHIFTS EAST OF THE AREA AFTER ABOUT 2 OR 3 IN THE AFTERNOON...SETTING THE STAGE FOR ANOTHER COLD NIGHT ACROSS SOUTHERN COLORADO. A FREEZE WATCH REMAINS IN EFFECT FOR A LARGE PART OF SOUTHEAST COLORADO FOR TONIGHT. LW .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 527 AM MDT FRI OCT 18 2013 NOT MANY METEOROLOGICAL LONGER TERM ADJUSTMENTS NEEDED FROM EARLIER FORECAST THINKING AS A GENERALLY DRY AND MILD LONGER TERM PATTERN IS EXPECTED TO DEVELOP OVER THE FORECAST DISTRICT. FROM SATURDAY INTO THURSDAY...LATER COMPUTER SIMULATIONS CONTINUE TO SUGGEST THAT A GENERALLY DRY AND MILD NORTHWESTERLY TO NORTHERLY UPPER FLOW PATTERN WILL BE NOTED OVER THE CWFA THANKS TO AN UPPER RIDGING PATTERN BUILDING OVER THE WESTERN UNITED STATES DURING THIS TIME-FRAME. AT THIS TIME...IT APPEARS THAT THE HIGHEST POTENTIAL FOR SHOWER ACTIVITY DURING THE LONGER TERM OVER THE FORECAST DISTRICT WILL OCCUR FROM LATER SUNDAY INTO MONDAY...ESPECIALLY OVER NORTHERN SECTIONS AS AN UPPER DISTURBANCE INTERACTS WITH A SURFACE NORTHERLY TO NORTHEASTERLY SURGE. MAXIMUM AND MINIMUM TEMPERATURES DURING THE LONGER TERM SHOULD BASICALLY RUN NEAR TO A FEW DEGREES ABOVE LATE OCTOBER CLIMATOLOGICAL AVERAGES...ALTHOUGH TEMPERATURES BELOW SEASONAL AVERAGES ARE ANTICIPATED MONDAY IN WAKE OF NORTHERLY/NORTHEASTERLY SURGE AND UPPER DISTURBANCE. FINALLY...LOW-GRADE GRADIENT WINDS ARE STILL ANTICIPATED OVER THE MAJORITY OF THE FORECAST DISTRICT DURING THE LONGER TERM. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 527 AM MDT FRI OCT 18 2013 FALL STORM SYSTEM WILL MOVE THROUGH CENTRAL AND EASTERN COLORADO THROUGH EARLY AFTERNOON...AND THEN SHIFT EAST OF THE AREA AFTER ABOUT 21Z. STORM SYSTEM WILL BRING SNOW SHOWERS TO THE CENTRAL MOUNTAINS AND PIKES PEAK REGION 12Z-18Z...WITH ACTIVITY LINGERING OVER THE EASTERN PLAINS AS LATE AS 21Z. AREAS OF MVFR/IFR/LIFR CONDITIONS WILL BE POSSIBLE IN CLOUDS AND PRECIPITATION. THIS INCLUDES THE KCOS TAF...AND WITH LESS CERTAINTY...THE KPUB TAF. CONDITIONS WILL LIKELY RETURN TO VFR AT THESE 2 SITES...ROUGHLY 16Z-18Z...AS THE SYSTEM SHIFTS EAST OF THE AREA. KALS SHOULD BE WEST OF THE ACTION WITH THIS EVENT...AND REMAIN VFR FOR THE DURATION. THIS GOES FOR THE BULK OF THE SAN LUIS VALLEY AND SOUTHWEST MOUNTAIN AREAS...WHERE ONLY SOME SPOTTY LIGHT RAIN AND SNOW SHOWERS ARE EXPECTED WITH THIS PARTICULAR STORM. LW && .PUB WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR COZ083-086-089-093>099. && $$ UPDATE...LW
AREA FORECAST DISCUSSION
NWS PUEBLO CO
533 AM MDT FRI OCT 18 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 527 AM MDT FRI OCT 18 2013 ...HIT AND RUN STORM ON THE WAY... IT`S ON OUR DOORSTEP. THE SHORTWAVE THAT HAS BEEN HEADED OUR WAY IS ABOUT TO ARRIVE. MULTIPLE LATE NIGHT TWEETS INDICATE SNOW HAS SPREAD QUICKLY SOUTH ACROSS THE NORTHERN FRONT RANGE URBAN CORRIDOR AND NORTHEAST PLAINS THIS MORNING. RADAR AND SURFACE REPORTS INDICATE THAT SNOW HAS ALREADY SPREAD INTO THE CENTRAL MOUNTAINS...INCLUDING LEADVILLE AND MONARCH PASS...AND IT IS JUST NOW CROSSING THE PALMER DIVIDE INTO NORTHERN TELLER AND NORTHERN EL PASO COUNTIES. ALL FORECAST MODELS AGREE THAT SNOW WILL MOVE INTO TELLER AND EL PASO COUNTIES THIS MORNING...WITH A MIXTURE OF RAIN AND SNOW SHOWERS SPREADING SOUTH ACROSS THE REST OF THE EASTERN MOUNTAINS AND PLAINS. THE GFS...AND TO A LESSER EXTENT...THE NAM HAVE BEEN GRADUALLY TRENDING BACK TOWARD BETTER CHANCES FOR PRECIPITATION OVER THE EASTERN MOUNTAINS AND PLAINS THAN THEY WERE 24 HOURS AGO. ADDITIONALLY...SHORT RANGE FORECASTS OFF OF THE HIGH RESOLUTION MODELS...INCLUDING THE HRRR AND THE WRF...ALSO SHOW AT LEAST SOME PRECIPITATION SPREADING SOUTH ACROSS MOST OF THE EASTERN MOUNTAINS AND PLAINS THIS MORNING. NONE OF THE MODELS HAVE ANYTHING VERY HEAVY...BUT THEY DO HAVE SOME LIGHT TO LOCALLY MODERATE AMOUNTS. RIGHT NOW...BEST BET IS FOR 1 TO 3 INCHES OF SNOW OVER THE CENTRAL MOUNTAINS AND PIKES PEAK...LOCAL 1 TO 2 INCHES AMOUNTS ACROSS TELLER AND EL PASO COUNTIES...AND GENERALLY AN INCH OR LESS ACROSS THE REST OF THE EASTERN MOUNTAINS AND PLAINS. PRECIP BELOW 5500 FEET WILL PROBABLY COME AS A MIXTURE OF RAIN AND SNOW SHOWERS...WHICH SHOULD HELP TO LIMIT ACCUMULATIONS. ELEVATIONS ABOVE 5500 FEET WILL SEE MOSTLY SNOW AND THE BEST CHANCES FOR ACCUMULATION. SECOND ONLY TO THE PIKES PEAK REGION...THE FAR EASTERN PLAINS ALONG THE KANSAS BORDER WILL SEE SOME OF THE BETTER ODDS FOR PRECIPITATION TODAY. LIGHT SNOW IS ALREADY FALLING AT BURLINGTON AND RADAR SHOWS DEVELOPING PRECIPITATION OVER NORTHEAST KIOWA COUNTY AT THIS TIME. THIS DEVELOPMENT SHOULD CONTINUE SOUTHWARD THROUGH THE MORNING INTO THE EARLY AFTERNOON HOURS. TEMPERATURES WILL BE A BIT BORDERLINE FOR MUCH IN THE WAY OF SNOW ACCUMULATION...BUT COULD BE SOME SPOTTY LIGHT AMOUNTS...ESPECIALLY ON GRASSY AREAS. EVERYTHING SHIFTS EAST OF THE AREA AFTER ABOUT 2 OR 3 IN THE AFTERNOON...SETTING THE STAGE FOR ANOTHER COLD NIGHT ACROSS SOUTHERN COLORADO. A FREEZE WATCH REMAINS IN EFFECT FOR A LARGE PART OF SOUTHEAST COLORADO FOR TONIGHT. LW .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 527 AM MDT FRI OCT 18 2013 NOT MANY METEOROLOGICAL LONGER TERM ADJUSTMENTS NEEDED FROM EARLIER FORECAST THINKING AS A GENERALLY DRY AND MILD LONGER TERM PATTERN IS EXPECTED TO DEVELOP OVER THE FORECAST DISTRICT. FROM SATURDAY INTO THURSDAY...LATER COMPUTER SIMULATIONS CONTINUE TO SUGGEST THAT A GENERALLY DRY AND MILD NORTHWESTERLY TO NORTHERLY UPPER FLOW PATTERN WILL BE NOTED OVER THE CWFA THANKS TO AN UPPER RIDGING PATTERN BUILDING OVER THE WESTERN UNITED STATES DURING THIS TIME-FRAME. AT THIS TIME...IT APPEARS THAT THE HIGHEST POTENTIAL FOR SHOWER ACTIVITY DURING THE LONGER TERM OVER THE FORECAST DISTRICT WILL OCCUR FROM LATER SUNDAY INTO MONDAY...ESPECIALLY OVER NORTHERN SECTIONS AS AN UPPER DISTURBANCE INTERACTS WITH A SURFACE NORTHERLY TO NORTHEASTERLY SURGE. MAXIMUM AND MINIMUM TEMPERATURES DURING THE LONGER TERM SHOULD BASICALLY RUN NEAR TO A FEW DEGREES ABOVE LATE OCTOBER CLIMATOLOGICAL AVERAGES...ALTHOUGH TEMPERATURES BELOW SEASONAL AVERAGES ARE ANTICIPATED MONDAY IN WAKE OF NORTHERLY/NORTHEASTERLY SURGE AND UPPER DISTURBANCE. FINALLY...LOW-GRADE GRADIENT WINDS ARE STILL ANTICIPATED OVER THE MAJORITY OF THE FORECAST DISTRICT DURING THE LONGER TERM. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 527 AM MDT FRI OCT 18 2013 FALL STORM SYSTEM WILL MOVE THROUGH CENTRAL AND EASTERN COLORADO THROUGH EARLY AFTERNOON...AND THEN SHIFT EAST OF THE AREA AFTER ABOUT 21Z. STORM SYSTEM WILL BRING SNOW SHOWERS TO THE CENTRAL MOUNTAINS AND PIKES PEAK REGION 12Z-18Z...WITH ACTIVITY LINGERING OVER THE EASTERN PLAINS AS LATE AS 21Z. AREAS OF MVFR/IFR/LIFR CONDITIONS WILL BE POSSIBLE IN CLOUDS AND PRECIPITATION. THIS INCLUDES THE KCOS TAF...AND WITH LESS CERTAINTY...THE KPUB TAF. CONDITIONS WILL LIKELY RETURN TO VFR AT THESE 2 SITES...ROUGHLY 16Z-18Z...AS THE SYSTEM SHIFTS EAST OF THE AREA. KALS SHOULD BE WEST OF THE ACTION WITH THIS EVENT...AND REMAIN VFR FOR THE DURATION. THIS GOES FOR THE BULK OF THE SAN LUIS VALLEY AND SOUTHWEST MOUNTAIN AREAS...WHERE ONLY SOME SPOTTY LIGHT RAIN AND SNOW SHOWERS ARE EXPECTED WITH THIS PARTICULAR STORM. LW && .PUB WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR COZ083-086-089-093>099. && $$
AREA FORECAST DISCUSSION
NWS TAUNTON MA
655 AM EDT FRI OCT 18 2013 .SYNOPSIS... AFTER SHOWERS AND CLOUDS CLEAR OUT EARLY THIS MORNING DRY WEATHER RETURNS INTO EARLY NEXT WEEK...OTHER THAN A FEW SHOWERS POSSIBLE SATURDAY NIGHT. UNSEASONABLY CHILLY WEATHER FOR LATE OCTOBER WILL ARRIVE BY LATE NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 7 AM UPDATE... COLD FRONT IS MOVING OFFSHORE ALONG THE EAST MASS COAST. SOME LINGERING CLOUDS IN RI AND EASTERN MASS BUT MOSTLY OVER THE CAPE AND ISLANDS. THESE CLOUDS SHOULD MOVE OFFSHORE THIS MORNING. ANOTHER AREA OF CLOUDS MOVING FROM NEW YORK STATE INTO WESTERN MASS AND VERMONT...AND WILL REACH PORTIONS OF CT AND SOUTHWEST NH THIS MORNING. EXPECT THESE CLOUDS TO DIMINISH DURING THE MORNING. FORECAST TEMPS AND DEWPTS WERE ABOUT 3F TOO COOL AT 6 AM. WE ADJUSTED THEM HIGHER WITH HELP FROM THE HRRR FIELDS. NO CHANGE TO FORECAST HIGH TEMPS AT THIS TIME. PREVIOUS DISCUSSION... GIVEN SKIES SHOULD TEND TOWARD SKC EVERYWHERE NOT LONG AFTER SUNRISE...MIXING TO H85 IS EXPECTED AS A RIDGE OF HIGH PRES APPROACHES FROM THE SW. TEMPS AT H85 AVERAGE AROUND +5C...SO EXPECT ANOTHER MILD MID OCTOBER DAY WITH HIGH TEMPS IN THE UPPER 60S AND LOWER 70S. MAY FEEL A BIT COOLER HOWEVER...AS BRISK W FLOW DEVELOPS. BL MIXING SHOULD BE ABLE TO TAP A 20-30 KT LLJ...SO WIND GUSTS OF 20-30 MPH ARE POSSIBLE THROUGHOUT THE DAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/... TONIGHT... RIDGE OF HIGH PRES BOTH AT THE SFC AND ALOFT WILL GRADUALLY CREST OVER THE REGION DURING THE OVERNIGHT HOURS. DRY SOUNDINGS SUGGEST MAINLY CLEAR TO PARTLY CLOUDY SKIES ARE A GOOD BET FOR THE OVERNIGHT HOURS. MASS FIELDS ALSO SUPPORT A RAPIDLY SLACKENING PRES GRADIENT AFTER 00Z...SO DO EXPECT A DECENT SETUP FOR OVERNIGHT RADIATIONAL COOLING. THEREFORE...DESPITE WARM DAY TEMPS TODAY...MINS ARE LIKELY TO DIP INTO THE LOW TO MID 40S AT SEVERAL LOCATIONS /WARMER...CLOSER TO 50 IN URBAN AREAS/. WHILE THESE WILL LIKELY FEEL COOL IN RELATION TO THE LAST COUPLE OF NIGHTS...THEY ARE FAIRLY CLOSE TO NORMAL FOR THIS TIME OF YEAR. SAT... A SEASONABLY COOL START WITH A FAIR AMOUNT OF SUNSHINE WILL GRADUALLY GIVE WAY TO INCREASING CLOUDINESS FROM BOTH THE S AND THE W AS TWO SEPARATE SHORTWAVE APPROACH FROM EACH OF THESE DIRECTIONS. ATTM...SAT SHOULD REMAIN MOSTLY DRY AS THESE WAVES ARE UNLIKELY TO PHASE AND HIGH PRES RIDGING REMAINS IN CONTROL WITH DECENT SUBSIDENCE ALOFT. MIXING LOOKS TO REACH CLOSE TO H85 AGAIN SUN...WITH TEMPS AT THIS LVL SIMILAR TO FRI. HOWEVER...THE INCREASE IN LATE DAY CLOUDS AND A COOLER START MAY MITIGATE DIURNAL TEMP INCREASE A BIT. THEREFORE...HAVE HIGHS A SHADE COOLER THAN FRI. MAINLY MID TO UPPER 60S. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... BIG PICTURE... THE PATTERN FOR NEXT WEEK IS DOMINATED BY MIDCONTINENT UPPER TROUGH WHICH SHIFTS EASTWARD MIDWEEK. ONE SHORTWAVE EJECTS FROM THE TROUGH AND MOVES ACROSS NEW ENGLAND SATURDAY NIGHT/SUNDAY MORNING. A SECOND SHORTWAVE MOVES SOUTH FROM THE CANADIAN ARCTIC AND THEN DIGS INTO THE BASE OF THE TROUGH MONDAY NIGHT...THEN EJECTS THROUGH NEW ENGLAND TUESDAY/TUESDAY NIGHT. THIS PATTERN FAVORS COLDER THAN NORMAL TEMPERATURES ESPECIALLY WEDNESDAY- THURSDAY. THE DAILIES... SATURDAY NIGHT... THE FIRST SHORTWAVE NOTED ABOVE PUSHES A COLD FRONT ACROSS THE REGION. BOTH GFS AND ECMWF SHOW A STRONG 140 KNOT UPPER JET MOVING FROM THE OHIO VALLEY ACROSS NEW ENGLAND. NORTHERN NEW ENGLAND IS FAVORED FOR UPPER VENTING IN THE LEFT EXIT REGION OF THIS JET. THE TRAILING RIGHT ENTRANCE REGION OF THE JET MOVES ACROSS SOUTHERN NEW ENGLAND DURING THE LATTER PART OF THE NIGHT. MODEL CROSS SECTIONS ALSO SHOW A DEEP BUT THREADY COLUMN OF MOISTURE LEADING THE COLD FRONT WITH A WEAK 1-2 MICROBAR/SEC LIFT. THIS ALLOWS CONFIDENCE OF SCATTERED SHOWERS/CHANCE POPS WITH THE FRONTAL PASSAGE BUT WITH HIGHER VALUES IN UPSTATE NY/VERMONT/NORTHERN NEW HAMPSHIRE. THIS PATTERN BEARS RESEMBLANCE TO THE FRONTAL PASSAGE OCCURRING AS THIS IS WRITTEN. TEMPS ARE A BLEND OF MOS VALUES. SUNDAY... COLD ADVECTION ON WEST TO NORTHWEST WINDS WILL BRING DRYING AND CLEARING SKIES. THE PASSING SHORTWAVE HAS A NOTICEABLE COLD POOL THAT MOVES ACROSS NORTHERN NEW ENGLAND...AND WHICH COULD CLIP OUR AREA ESPECIALLY NORTH OF THE MASS PIKE. MOISTURE FIELDS SHOW 70+% RELATIVE HUMIDITY IN THE 800-900 MB LAYER. THE MOISTURE AND DESTABILIZATION SHOULD LEAD TO SOME CLOUD DEVELOPMENT DURING THE DAY. TEMPS ALOFT AT THE TOP OF THE MIXED LAYER SHOULD SUPPORT MAX SURFACE TEMPS IN THE UPPER 50S TO MID 60S. WINDS IN THIS MIXED LAYER ARE FORECAST AT 15-20 KNOTS WHICH IS MUCH HIGHER THAN MODEL WIND GUST FORECASTS...WE BUMPED GUSTS UP ABOUT 5-8KTS TO REFLECT THIS WIND POTENTIAL. SUNDAY NIGHT...HIGH PRESSURE BUILDS IN FROM THE SOUTHWEST. THIS SHOULD PROVIDE MOSTLY CLEAR SKIES AND LIGHT WINDS. DEWPOINTS WILL BE IN THE MID 30S...SO MIN TEMPS SHOULD REACH THIS LEVEL ACROSS A WIDE AREA. POTENTIAL FOR WIDESPREAD FROST. MONDAY THROUGH THURSDAY... HIGH PRESSURE IN CONTROL MONDAY WITH DRY COOL WEATHER. THE SECOND UPPER SHORTWAVE PUSHES A COLD FRONT ACROSS NEW ENGLAND TUESDAY OR TUESDAY EVENING. UPPER SUPPORT IS SUFFICIENT FOR SHOWERS BUT MOISTURE IS LIMITED. SO WE HAVE LOW-END CHANCE POPS. THE UPPER TROUGH AND COLD POOL WILL LINGER IN THE VICINITY WEDNESDAY AND THURSDAY WHICH MAY LEAD TO MORE SKY COVER THAN IS CURRENTLY IN THE FORECAST. IT WILL ALSO MEAN COLDER TEMPS THAN ON MONDAY AND TUESDAY. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH SATURDAY/... HIGH CONFIDENCE IN TRENDS. LOWER CONFIDENCE IN EXACT TIMING OF IMPROVEMENT THIS MORNING. LINGERING CIGS 500-1000 FEET OVER THE CAPE AND ISLANDS AT SUNRISE. BUT THE CLEARING LINE IS PROGRESSING EAST AND SHOULD MOVE OFFSHORE BY 8 AM. A SECOND BATCH OF LOW CLOUDS OVER THE BERKSHIRES IS MOVING INTO THE CT VALLEY. BUT EXPECT THE DOWNHILL MOTION TO WARM THE AIR AND EVAPORATE THE LOWER PORTIONS OF THESE CLOUDS...SO EXPECT VFR CIGS OVER THE CT VALLEY THIS MORNING. THESE CLOUDS SHOULD BREAK AS THEY MOVE EAST. VFR THE REMAINDER OF THE DAY. PATCHY FOG POSSIBLE TONIGHT IN THE USUAL PROTECTED VALLEYS. CIGS AT OR BELOW 500 FEET IN FOG AREAS AND VSBYS 1 MILE OR LESS. INCREASING CLOUDS SATURDAY AS A COLD FRONT APPROACHES FROM THE GREAT LAKES. BUT MOSTLY HIGH-BASED CLOUDS THROUGH THE DAY. VFR CONDITIONS EXPECTED. WEST WINDS WILL DRAW GUSTS OF 20-30 KT TO THE SURFACE...DIMINISHING THIS EVENING. WEAKER WIND TONIGHT AND SAT. KBOS TERMINAL...HIGH CONFIDENCE IN TAF TRENDS...WEST WINDS GUST 20-30 KT AT TIMES TODAY...ABOUT 10 TO 20 DEGREES EITHER SIDE OF 270. KBDL TERMINAL...HIGH CONFIDENCE IN TRENDS...WEST WINDS GUST UP TO 20-25 KT AT TIMES TODAY. OUTLOOK...SATURDAY NIGHT THROUGH TUESDAY... MODERATE CONFIDENCE. COLD FRONTS WILL MOVE ACROSS THE REGION ON SATURDAY NIGHT AND TUESDAY WITH POTENTIAL MVFR/IFR CIGS/VSBYS IN SHOWERS EACH TIME. OTHERWISE VFR THROUGH THE PERIOD. WEST TO NORTHWEST WINDS SUNDAY MAY GUST AROUND 20 KNOTS. SOUTHWEST WINDS TUESDAY MAY GUST 20-25 KNOTS. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH SATURDAY/...HIGH CONFIDENCE. THROUGH TONIGHT... BUILDING SEAS WILL CONTINUE RISE THROUGH MID AFTERNOON BUT THEN BEGIN TO DECLINE UNDER WESTERLY BREEZES. SEAS WILL DROP BELOW 5 FT ON OCEAN WATERS LATE TONIGHT. OTHERWISE...W WINDS INCREASE DURING THE DAYLIGHT HOURS TODAY...WITH SOME GUSTS 25-30 KT POSSIBLE...ESPECIALLY NEAR SHORES. SMALL CRAFT ADVISORIES CONTINUE THROUGH THE DAY TODAY OVER ALL WATERS. THEN DROP OFF DURING THE OVERNIGHT TONIGHT. SATURDAY... HIGH PRES OVER THE WATERS WILL LEAD TO GENERALLY QUIET BOATING WEATHER...SEAS WILL REMAIN BELOW 5 FT AND SW WINDS GUST UP TO 15 KT. OUTLOOK...SATURDAY NIGHT THROUGH TUESDAY... MODERATE CONFIDENCE SATURDAY NIGHT-SUNDAY...A COLD FRONT MOVES ACROSS THE WATERS SATURDAY NIGHT. WEST TO NORTHWEST WINDS TRAILING THE FRONT MAY GUST TO 25 KNOTS ON SUNDAY. A SMALL CRAFT ADVISORY MAY BE NEEDED. MONDAY-TUESDAY...HIGH PRESSURE AND FAIR WEATHER MONDAY SHOULD KEEP WINDS AND SEAS QUIET. AN APPROACHING COLD FRONT TUESDAY WILL BRING SCATTERED SHOWERS. SOUTHWEST WINDS WILL INCREASE AHEAD OF THE FRONT WITH GUSTS OF 25-30 KNOTS. THIS WILL BUILD SEAS WITH 5 TO 7 FOOT HEIGHTS ON THE EXPOSED WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED TUESDAY. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ231>234-251. SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 8 PM EDT THIS EVENING FOR ANZ230-236. SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR ANZ235-237. SMALL CRAFT ADVISORY UNTIL 5 AM EDT SATURDAY FOR ANZ250- 254>256. && $$ SYNOPSIS...WTB/DOODY NEAR TERM...WTB/DOODY SHORT TERM...DOODY LONG TERM...WTB AVIATION...WTB/DOODY MARINE...WTB/DOODY
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1051 AM EDT FRI OCT 18 2013 .SYNOPSIS... A WEAK COLD FRONT WILL MOVE INTO THE AREA TODAY AND LINGER TONIGHT...AS A WAVE OF LOW PRESSURE DEVELOPS ALONG THE FRONT. THE FRONT WILL REMAIN POSITIONED ALONG THE SOUTHEAST COAST ON SATURDAY...SHIFTING OFFSHORE SUNDAY AS HIGH PRESSURE BUILDS EARLY NEXT WEEK. A WEAK WAVE OF LOW PRESSURE WILL MOVE NORTHEAST ALONG THE REMNANT OFFSHORE FRONT THROUGH THE MIDDLE OF NEXT WEEK. MUCH COOLER CANADIAN HIGH PRESSURE WILL MOVE IN FOR THE LATTER PART OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... LATEST SURFACE ANALYSIS PLACES A TROUGH ALONG THE SOUTHEAST COASTLINE THIS MORNING...WITH A WEAK FRONT HAVING PROGRESSED INTO THE FORECAST AREA. MOISTURE CONVERGENCE ALONG THE FRONTAL ZONE HAS ALLOWED A SWATH OF THICK CLOUD COVER TO SHIFT INTO THE REGION...AS PRECIPITABLE WATER VALUES HAVE INCREASED TO AROUND 1.85 INCHES ACCORDING TO THE CHARLESTON SOUNDING. LIMITED UPPER LEVEL SUPPORT WITHIN SOME NEGATIVE VORTICITY ADVECTION HAS CONFINED SHOWER ACTIVITY TO A NARROW LINE CURRENTLY STRETCHING FROM SOUTHERN GEORGIA INTO CENTRAL SOUTH CAROLINA. THE WEAK FRONT WILL REMAIN STALLED OVER THE FORECAST AREA DURING THE DAYTIME HOURS AS IT BECOMES PARALLEL TO THE FLOW ALOFT AND FEELS THE EFFECTS OF A BLOCKING RIDGE FAR TO THE EAST/SOUTHEAST. DESPITE MOSTLY CLOUDY SKIES PREVAILING FOR MUCH OF THE DAY...TEMPERATURES WILL RISE WELL ABOVE SEASONAL NORMALS DUE TO PRE-FRONTAL COMPRESSION AND A MORE PERSISTENT WARM WESTERLY FLOW REGIME AHEAD OF THE SLOWING FRONT. A SEABREEZE CIRCULATION WILL ACTUALLY BECOME WELL-DEFINED AS A RESULT OF BOTH THESE WARMER CONDITIONS AND THE WEAK PRESSURE PATTERN WITHIN THE SURFACE TROUGH. THE MAIN QUESTION THEN BECOMES WHETHER INCREASED FORCING PRODUCED BY THE COMBINED EFFECTS OF THE SEABREEZE...LINGERING FRONT AND SURFACE TROUGH WILL BE SUFFICIENT TO SPREAD PRECIPITATION COVERAGE ACROSS THE FORECAST AREA DURING THE NEXT SEVERAL HOURS. SHORT RANGE MODEL SOLUTIONS VARY IN COVERAGE DETAILS AND FAVORED LOCATIONS...YET THE GENERAL TREND IS FOR AT LEAST LIGHT SHOWER ACTIVITY TO GENERALLY SHIFT EAST/NORTHEAST AS THE DAY PROGRESSES...PERHAPS CONCENTRATING JUST INLAND OF THE COAST NEAR THE SEABREEZE. ONGOING PRECIPITATION FORECAST APPEARS ON TRACK WITH THIS SCENARIO...AND WILL LIKELY MAKE NO CHANGES WITH THE LATE MORNING UPDATE. RAP MODEL FORECAST FOR THIS AFTERNOON HINTS AT A SMALL AREA OF SLIGHTLY HIGHER INSTABILITY SLIPPING NORTH OF THE ALTAMAHA RIVER IN GEORGIA...WHERE LESS CLOUD COVER CURRENTLY PREVAILS THIS MORNING. THUS ISOLATED THUNDER COULD OCCUR GENERALLY SOUTH OF INTERSTATE 16...ESPECIALLY WHERE AN INTERACTION WITH THE SEABREEZE TAKES PLACE. HOWEVER...OVERALL RAINFALL AMOUNTS STILL LOOK RATHER UNIMPRESSIVE IN THE 0.05 TO 0.15 INCH RANGE. TONIGHT...A DEEP FEED OF SUB-TROPICAL MOISTURE WILL EXTEND ACROSS THE SOUTHEAST STATES...RESULTING IN PRECIPITABLE WATER VALUES THAT WILL CLIMB TO NEARLY 2 STANDARD DEVIATIONS ABOVE MID OCTOBER LEVELS. THE COLD FRONT WILL INCH ITS WAY TOWARD THE COAST...ALTHOUGH THIS WILL BE A LABORING PROCESS AS SHORT WAVE ENERGY WILL ARRIVE FROM THE GULF AND TRIGGER THE DEVELOPMENT OF WEAK LOW PRESSURE ALONG THE FRONT. WATER VAPOR SATELLITE IMAGERY IS CLEARLY DEPICTING THE SHORT WAVE ENERGY AND FEED OF MOISTURE FROM TEXAS AND OLD MEXICO. THE WAVE OF LOW PRESSURE WILL RIDE NORTHEAST OVER THE EASTERN ZONES FROM ABOUT 03-09Z...BEFORE IT LIFTS AWAY LATE. THIS WILL ALLOW FOR THE COLD FRONT TO FINALLY SWING INTO THE NEARBY ATLANTIC BY 12Z SATURDAY. GIVEN BETTER DYNAMICS ALOFT...HAVE INCREASED RAIN CHANCES INTO THE 30-60 PERCENT RANGE...GREATEST NEAR THE TRACK OF THE SURFACE WAVE OVER EASTERN ZONES...MOST ESPECIALLY OVER CHARLESTON AND BERKELEY COUNTIES. LOW TEMPERATURES WILL BE AT THE WARMEST LEVELS FOR THE REMAINDER OF THE FORECAST PERIOD...DROPPING NO LOWER THAN THE LOW/MID 60S INLAND...TO THE UPPER 60S TO AROUND 70 CLOSER TO THE OCEAN. && .SHORT TERM /SATURDAY THROUGH MONDAY/... SATURDAY AND SATURDAY NIGHT...THE PERIOD BEGINS WITH MUCH OF THE COUNTRY UNDER THE INFLUENCE OF A LONGWAVE MID/UPPER LEVEL TROUGH CENTERED ALONG THE MS VALLEY. THE EMBEDDED SHORTWAVE WILL DAMPEN OUT AS IT LIFTS TO THE NORTHEAST WITH THE FORECAST AREA REMAINING UNDER SOUTHWEST FLOW ALOFT THROUGH THE PERIOD. A COLD FRONT WILL START THE DAY IN THE VICINITY OF THE AREA...ROUGHLY ORIENTED ALONG THE SOUTHEAST COASTLINE. THE FRONT WILL SHIFT EASTWARD THROUGH SATURDAY NIGHT AS HIGH PRESSURE OVER THE SOUTHERN PLAINS BUILDS IN FROM THE WEST. THE BEST TIME FOR PRECIP WILL BE SATURDAY MORNING ALONG THE SC COASTLINE THANKS TO SOME LOW LEVEL ISENTROPIC LIFT AND THE PRESENCE OF UPPER DIVERGENCE IN THE RIGHT ENTRANCE REGION OF A 130+ KT 300 MB JET. THE TREND IS THEN FOR POPS TO DECREASE THROUGH THE DAY AS DRIER AIR FILTERS IN AND THE FRONT SHIFTS OFFSHORE. I HAVE FAVORED POPS ALONG THE COAST IN THE HIGH CHANCE RANGE WITH A SMALL AREA OF LIKELY POPS FOR EASTERN BERKELEY AND CHARLESTON COUNTIES. TEMPS WILL BE HELD DOWN THANKS TO PLENTIFUL CLOUDS AND MORNING PRECIP...KEEPING HIGHS IN THE MID/UPPER 70S. OVERNIGHT...CLOUDS WILL GRADUALLY THIN AND DECREASE IN COVERAGE WITH A PRIMARILY DRY FORECAST OVER LAND. LOWS WILL FALL INTO THE UPPER 50S INLAND AND LOW 60S CLOSER TO THE BEACHES. SUNDAY THROUGH MONDAY...THE FLOW ALOFT WILL BECOME NEARLY ZONAL FOR A TIME BEFORE STARTING TO AMPLIFY EARLY NEXT WEEK AS A DEEP CLOSED LOW DIVES SOUTHWARD AND INTO THE GREAT LAKES REGION. HIGH PRESSURE WILL EXPAND ACROSS THE REGION ON SUNDAY AND THEN SHIFT OFFSHORE MONDAY. EXPECT A DRY AND TRANQUIL DAY ON SUNDAY. MONDAY WILL GENERALLY BE QUIET AS WELL...THOUGH WITH THE HIGH SHIFTING OFFSHORE THE REMNANT FRONT OVER THE ADJACENT WATERS WILL BEGIN TO SHIFT BACK TOWARDS LAND. AS IT DOES SOME MOISTURE RETURN WILL SET UP AND WE MAY EVEN SEE A FEW SHOWERS DEVELOPING ACROSS FAR SOUTHEAST GA NEAR THE ALTAMAHA. SLIGHT CHANCE POPS TO CREEP IN FROM THE SOUTH...THOUGH MUCH OF ANY ACTIVITY WILL BE LATE IN THE DAY. TEMPS WILL BE RIGHT AROUND CLIMO WHICH MEANS MID/UPPER 70S IN MOST AREAS FOR HIGHS AND LOW/MID 50S FOR LOWS. && .LONG TERM /MONDAY NIGHT THROUGH THURSDAY/... OVERALL CONFIDENCE IN THE LONG TERM PERIOD IS RELATIVELY GOOD. MOST OF THE ACTIVITY IN THE PERIOD WILL BE EARLY ON...WITH THE LATTER PORTION DOMINATED BY HIGH PRESSURE. THE AFOREMENTIONED REMNANT FRONT WILL BE ORIENTED ALONG AND NEAR THE AREA MONDAY NIGHT INTO TUESDAY. DEEP MOISTURE WILL INCREASE ACROSS THE REGION AND MUCH OF THE FORCING WILL BE PROVIDED BY UPPER DIVERGENCE IN THE RIGHT ENTRANCE REGION OF A STRENGTHENING JET THAT IS EXPECTED TO STRETCH FROM THE SOUTHERN APPALACHIANS TO THE MID ATLANTIC. THE TIME PERIOD FOR THE BEST CHANCES WILL OCCUR LATE MONDAY NIGHT AND INTO TUESDAY. POPS HAVE BEEN KEPT IN THE HIGH CHANCE RANGE FOR NOW AND MAY NEED AN UPWARD ADJUSTMENT IF THIS FORECAST SCENARIO CONTINUES TO PLAY OUT. BY WEDNESDAY...EXPANSIVE CANADIAN HIGH PRESSURE WILL SINK SOUTHWARD ACROSS THE PLAINS AND BEGIN TO BUILD INTO THE REGION. THIS WILL BRING ABOUT CLEARING SKIES AND THE POTENTIAL FOR MUCH COOLER TEMPERATURES. IN FACT...850 MB TEMPS ARE PROGGED TO FALL WELL INTO THE SINGLE DIGITS AND BRING ABOUT THE COOLEST TEMPS OF THE SEASON THUS FAR. IT IS WORTH NOTING THAT MODEL LOW LEVEL THICKNESS VALUES WOULD ONLY SUPPORT LOW/MID 60S FOR HIGHS BY LATE IN THE WEEK. && .AVIATION /14Z FRIDAY THROUGH TUESDAY/... KCHS...A COLD FRONT WILL STALL IN THE VICINITY THROUGH TONIGHT...AS A WAVE OF LOW PRESSURE RIDES NORTHEAST ALONG THE FRONT. THIS WILL TRIGGER THE DEVELOPMENT OF SCATTERED SHRA WITH A LOW-END CHANCE OF ISOLATED TSRA. ALTHOUGH PREFER TO KEEP FLIGHT RESTRICTIONS OUT OF THE FORECAST AT THIS POINT DUE TO TIMING/COVERAGE UNCERTAINTIES...PERIODIC MVFR WEATHER IS STILL POSSIBLE. LATER TAF ISSUANCES WILL LIKELY BE ABLE TO BECOME MORE DETERMINISTIC. KSAV...VFR CONDITIONS WILL PREVAIL THROUGH LATE TODAY...UNTIL SCATTERED SHRA AND ISOLATED TSRA DEVELOP IN ASSOCIATION WITH THE SEA BREEZE AND AN APPROACHING COLD FRONT/WAVE OF LOW PRESSURE INTO TONIGHT. THERE IS A LOW TO MODERATE RISK OF PERIODIC FLIGHT RESTRICTIONS WITHIN ANY CONVECTION AND EVENTUALLY IN LATE NIGHT MIST. EXTENDED AVIATION...MVFR CONDITIONS MAY LINGER THROUGH SATURDAY MORNING. VFR FOR SUNDAY AND MONDAY. ANOTHER ROUND OF RESTRICTIONS WILL BE POSSIBLE ON TUESDAY AS A FRONT AFFECTS THE AREA. && .MARINE... TODAY AND TONIGHT...A WEAK PRESSURE PATTERN WILL PREVAIL...AS THE LOCAL WATERS BECOME LOCATED BETWEEN A SLOW MOVING COLD FRONT TO THE NW AND WEAKENING HIGH PRESSURE OFF TO THE SE. WINDS WILL BE MAINLY SOUTH OR SOUTHWEST AT 15 KT OR LESS TODAY INTO EARLY TONIGHT...THEN VEER AROUND TO THE SOUTHWEST AND WEST OVERNIGHT. WIND SPEEDS WILL ALSO INCREASE A FEW KNOTS...AS A WEAK LOW LEVEL JET CROSSES THE MARINE AREA. WAVE ENERGY IS MAINLY COMPRISED OF 8-10 SECOND SWELLS...AND WITH SIGNIFICANT WAVE HEIGHTS WILL ACHIEVE NO MORE THAN 2 OR 3 FT. MARINERS ARE ADVISED THAT ISOLATED THUNDERSTORMS COULD OCCUR TONIGHT IN ADVANCE OF THE COLD FRONT. SATURDAY THROUGH WEDNESDAY...A COLD FRONT WILL WORK ITS WAY ACROSS THE WATERS SATURDAY WITH HIGH PRESSURE BUILDING IN FROM THE WEST ON SUNDAY. THE HIGH WILL REMAIN THE DOMINANT FEATURE THROUGH THE WEEKEND...BEFORE THE FRONT WORKS ITS WAY BACK TOWARD THE AREA LATE IN THE PERIOD. WIND/SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS THROUGH THE PERIOD. WINDS WILL PRIMARILY SEE SHIFTING DIRECTIONS AS THE HIGH BUILDS IN...PASSES BY TO THE NORTH...AND THEN OFF THE MID ATLANTIC COAST. WINDS WILL PREDOMINANTLY BECOME NE AND THEN E SUNDAY THROUGH MONDAY...THEN AROUND TO THE NW BY MID WEEK. && .TIDES/COASTAL FLOODING... CONDITIONS WILL PROBABLY FALL SHORT OF COASTAL FLOODING CRITERIA WITH THE EVENING HIGH TIDE...DESPITE THE OCCURRENCE OF THE FULL HUNTERS MOON AT 2338 UTC. ALTHOUGH WINDS WILL NOT BE MUCH OF A FACTOR...LINGERING ASTRONOMICAL INFLUENCES WILL RESULT IN ELEVATED TIDES THIS WEEKEND. WINDS WILL INCREASE AND VEER AROUND TO THE NORTHEAST EARLY NEXT WEEK...COMPENSATING FOR THE WANING EFFECTS OF THE FULL MOON. AS A RESULT...COASTAL FLOOD ADVISORIES ARE POSSIBLE INTO MONDAY OR EVEN POSSIBLY TUESDAY. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && $$ NEAR TERM...WMS SHORT TERM...BSH LONG TERM...BSH AVIATION...WMS MARINE...WMS/BSH TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS GRAY ME
652 AM EDT FRI OCT 18 2013 .SYNOPSIS... HIGH PRESSURE BUILDS BACK ACROSS THE AREA THROUGH SATURDAY BEFORE A COLD FRONT BRINGS SHOWERS AND A SHOT OF COLDER AIR SATURDAY NIGHT. HIGH PRESSURE BUILDS EAST THROUGH MONDAY BEFORE ANOTHER STRONGER FRONT CROSSES THE AREA LATE TUESDAY. UNSETTLED WEATHER WILL CONTINUE THROUGH THE END OF THE WORK WEEK. && .NEAR TERM /THROUGH TONIGHT/... UPDATE... LATEST HRRR MODEL RUN CONTINUES TO SHOW THE SHOWER ACTIVITY RAPIDLY EXITING THE FORECAST AREA THIS MORNING. ANY REMAINING PRECIPITATION LIES EAST OF THE ME/NH LINE AS OF 11Z. WILL ADJUST PROBABILITY OF PRECIPITATION ACCORDINGLY. WILL ALSO ALLOW FOR ADJUSTMENTS TO THE WIND FIELDS AS DRAINAGE WINDS CONTINUE NORTH AND EAST OF PORTLAND. FOG CONTINUES ACROSS THE REGION AS WELL...HOWEVER VISIBILITIES WILL SLOWLY IMPROVE WITH TIME EARLY THIS MORNING. HYDRO SITUATION FOR THE GORHAM DAM... HAVE EXTENDED THE FLASH FLOOD WATCH FOR THE GORHAM AREA FOR A COUPLE MORE HOURS THIS MORNING AS WE AWAIT NEW INFORMATION ON THE GORHAM DAM. FLASH FLOOD WATCH IS NOW IN EFFECT UNTIL 9 AM. PREV DISC... A FAST MOVING AREA OF LOW PRESSURE WILL RACE EAST OF OUR REGION THIS MORNING. THIS WILL ALLOW FOR CLEARING SKIES INITIALLY OVER DOWNSLOPE AREAS...FOLLOWED BY SLOW CLEARING IN THE MOUNTAINS. WITH COLD AIR ADVECTION AND INCREASING MIXING VALUES...WINDS MAY BE GUSTY AT TIMES. TEMPERATURES WILL STILL MANAGE TO MAKE IT INTO THE 60S IN MOST AREAS. USED A BLEND OF MET/MAV GUIDANCE FOR DAYTIME MAXES THIS AFTERNOON. && .SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/... MAINLY CLEAR SKIES WILL CONTINUE DURING THE OVERNIGHT PERIOD...WITH STILL SOME UPSLOPE CLOUDINES IN THE WNW FACING HIGHER TERRAIN. THERE WILL BE SOME PATCHY FOG IN THE MORE SHELTERED VALLEYS. A WEAK AND FAST MOVING RIDGE OF HIGH PRESSURE WILL CROSS NORTHERN NEW ENGLAND EARLY SATURDAY MORNING. THIS WILL BE FOLLOWED BY A DISTURBANCE EMBEDDED IN THE INCREASEING SW FLOW ALOFT. CLOUDS WILL BE ON THE INCREASE DURING THE DAY AS A WEAK AREA OF LOW PRESSURE FORMS OFF THE MID ATLANTIC COAST. && .LONG TERM /SUNDAY THROUGH THURSDAY/... HIGH PRESSURE MOVES OFFSHORE SATURDAY AND ALLOWS A WARMER SOUTHWEST FLOW TO DEVELOP ACROSS THE AREA SATURDAY IN ADVANCE OF THE NEXT FRONTAL SYSTEM WHICH WILL MOVE THROUGH THE REGION SATURDAY NIGHT. SCATTERED SHOWERS WILL SPREAD ACROSS THE REGION LATE SATURDAY AND SAT NIGHT IN ADVANCE OF THE COLD FRONT. HIGH PRESSURE QUICKLY BUILDS IN FOR SUNDAY AND MONDAY. TEMPERATURES STAY NEAR SEASONAL NORMALS WITH A FAIR AMOUNT OF SUNSHINE. THE NEXT FRONT IS EXPECTED TO MOVE ACROSS THE REGION LATE TUESDAY INTO TUESDAY NIGHT. SHOWERS ONCE AGAIN CAN BE EXPECTED ALONG AND AHEAD OF THE FRONT. BEHIND THE FRONT A MUCH COLDER AIR MASS WILL FILTER ACROSS THE AREA WITH SNOW SHOWERS IN THE MOUNTAINS EXPECTED ON WEDNESDAY. BY WED NIGHT OR THU NIGHT FROST OR FREEZING CONDITIONS ARE EXPECTED TO REACH THE COASTAL AREAS. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... SHORT TERM...CEILINGS AND VISIBILITIES WILL REMAIN LOW THROUGH DAYBREAK AS A COLD FRONT PUSHES THROUGH. MANY SITES WILL SEE IFR/LIFR CONDITIONS BETWEEN 08Z AND 14Z. CONDITIONS WILL RAPIDLY IMPROVE THEREAFTER. LONG TERM... VFR SATURDAY. COULD SEE MVFR/IFR IN SHOWERS SATURDAY NIGHT. SHOULD BE VFR AGAIN SUNDAY THROUGH EARLY TUESDAY. && .MARINE... SHORT TERM...SCA CONTINUES AND HAS BEEN EXTENDED THROUGH TONIGHT...AS A COLD FRONTAL PASSAGE INCREASES WIND GUSTS AND WAVE HEIGHTS. LONG TERM... WINDS/SEAS TO REMAIN BLO SCA CONDS THROUGH MONDAY. WINDS/SEAS WILL INCREASE AND REACH SCA CONDS TUES DUE TO AN INCRG SLY GRADIENT AHEAD OF AN APPROACHING CDFNT. THE COLD FRONT MOVES ACROSS THE WATERS TUES NIGHT WITH GSTY WLY WINDS BEHIND THE FROPA THAT WILL CONTINUE THROUGH WED. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...FLASH FLOOD WATCH UNTIL 9 AM EDT THIS MORNING FOR NHZ002. MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR ANZ150-152- 154. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS MARQUETTE MI
1016 AM EDT FRI OCT 18 2013 .UPDATE... ISSUED AT 1014 AM EDT FRI OCT 18 2013 SFC LOW CURRENTLY OVER EASTERN LK SUPERIOR BETWEEN CARIBOU ISLAND AND WHITEFISH POINT. TROUGH EXTENDING WEST FROM THE LOW WITH NNW WINDS ALREADY NEAR THE SHORE AT MQT AND PUSHING TOWARD MUNISING. COOLING IN WAKE OF TROUGH IS SPILLING ACROSS LK SUPERIOR LEADING TO INCREASING OVERWATER INSTABILITY. BASED ON H85 TEMPS FM RUC THE DELTA T/S RIGHT NOW OVER LK SUPERIOR ARE 12-14C. SHOWERS STREAMING IN OFF LK SUPERIOR BTWN MARQUETTE AND MUNISING ARE LIKELY A RESULT OF INSTABILITY AND LOW-LEVEL CONVERGENCE. ELSEWHERE...WIDESPREAD RAIN IS OCCURRING OVER MUCH OF THE NORTHERN CWA. RAIN AMOUNTS LIGHT WITH AVAILABLE AUTOMATED STATIONS SHOWING ONLY A HUNDREDTH OR TWO IN AN HOUR. AS SHORTWAVE TO THE WEST SLIDES ACROSS THROUGH EARLY THIS AFTN AND INTERACTS WITH NNW CYCLONIC FLOW AND THE INCREASING INSTABILITY...EXPECT SHOWERS OVER THE WEST TO INCREASE OVER THE HIGHER TERRAIN. RUC13 MAY BE OVERDONE WITH ITS QPF AMOUNTS...BUT IS PROBABLY ON THE RIGHT TRACK WITH AT LEAST THE AREAL DEPICTION. MAIN ADJUSTMENT WAS TO INCREASE POPS ALL AREAS THROUGH THE MORNING FOR THE WIDESPREAD LIGHT RAIN...THEN KEEP HIGHER POPS LONGER OVER THE WEST THIS AFTN DUE TO THE LK EFFECT. PRECIP WILL TREND DOWN THIS EVENING AS SFC TROUGH MOVES EAST OF THE AREA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 507 AM EDT FRI OCT 18 2013 RAIN SHOWERS OVER THE WRN CWA AND PARTS OF MN AND WI ARE BEING DRIVEN BY A COLD FRONT ALONG THE LEADING EDGE OF THE SHOWERS...SUCH AS WHERE HIGHER RADAR REFLECTIVITIES AND GRADIENTS ARE OVER SCENTRAL LAKE SUPERIOR/NCENTRAL UPPER MI AT THE CURRENT TIME /0730Z/. BEHIND THE INITIAL COLD FRONTAL PRECIP...THE WIDESPREAD RAIN IS BEING DRIVEN BY A SHORTWAVE NEAR MPX AND UPPER LEVEL HEIGHT FALLS FROM A STRONG UPPER TROUGH PUSHING INTO THE REGION FROM THE N. EVEN WITH SUB FREEZING 850MB TEMPS BEHIND THE COLD FRONT...THERE IS NO SNOW BEING REPORTED AS LOW LEVEL TEMPS BELOW 850MB ARE TOO WARM FOR FROZEN PRECIP TO MAKE IT TO THE GROUND. EXPECT BEST COVERAGE OF RAIN TO BE OVER WRN UPPER MI THROUGH MOST OF THE MORNING AS THE COLD FRONT OUTRUNS BEST UPPER LEVEL SUPPORT /KEEPING RAIN COVERAGE LOWER AS THE FRONT MOVES E/ AND THE SHORTWAVE MOVES OVER WRN UPPER MI AROUND 18Z. BEHIND THE SHORTWAVE AND AHEAD OF THE UPPER TROUGH AXIS...A BRIEF RIDGE PASSES THROUGH TONIGHT...WHICH SHOULD PROVIDE A LULL IN PRECIP. HOWEVER...AFTER THE RIDGE PASSES...CONDITIONS BECOME MORE FAVORABLE FOR LAKE EFFECT/ENHANCED PRECIP AS 850MB TEMPS WILL BE AROUND -3C OVER THE RELATIVELY WARM 8-10C WATERS OF LAKE SUPERIOR WITH NW LOW LEVEL WINDS. THINK THE INCREASE IN SHOWER COVERAGE WILL BE LATE TONIGHT AFTER 03Z. WITH THE COLDER 850MB TEMPS...SOME SNOW COULD MIX IN WITH THE RAIN LAT TONIGHT WHEN NEAR SFC TEMPS ARE COOLER. STILL NOT EXPECTING ANY SNOWFALL ACCUMULATIONS IN THE SHORT TERM.. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 507 AM EDT FRI OCT 18 2013 SATURDAY AND SATURDAY NIGHT...THE MODELS WERE IN REASONABLE AGREEMENT IN DROPPING A SHORTWAVE INTO THE REGION WITH THE STRONGEST 850-500 MB QVECTOR CONV TO THE SOUTH OF UPPER MI. HOWEVER...THE FORCING AHEAD OF THE SHRTWV ALONG WITH RELATIVELY STEEP 900-600 MB LAPSE RATES WILL BE STRONG ENOUGH TO SUPPORT SCT/NMRS SHOWERS SPREADING FROM WEST TO EAST THROUGH THE CWA. FCST SOUNDINGS SUGGEST THAT A RAIN/SNOW MIX WILL BE POSSIBLE IN THE MORNING BEFORE DIURNAL WARMING AND WEAK WAA CHANGES THE PCPN OVER TO RAIN. WITH MAINLY W OR WNW WINDS BY SAT NIGHT AND 850 MB TEMPS DOWN TO AROUND -4C...THE BEST CHANCE FOR ENHANCED SHOWERS ARE EXPECTED MAINLY OVER THE KEWEENAW AND LOCATIONS EAST OF MUNISING. SUN INTO MON...THE GFS AND ECMWF REMAINED IN GOOD AGREEMENT WITH A STRONGER SHRTWV DROPPING TO THE SOUTH FROM NRN MANITOBA. AS THE ASSOCIATED SFC LOW MOVES FROM WI TO ERN UPPER MI...AN AREA OF 285K-295 ISENTROPIC LIFT WILL SUPPORT AN AREA OF PCPN MOVING INTO SW UPPER MI SUN AFTERNOON AND ACROSS THE CWA SUN NIGHT. FCST SOUNDINGS...AND WET-BULB ZERO HEIGHTS SUPPORT POTENTIAL FOR ACCUMULATING SNOW OVER THE HIGHER TERRAIN OF THE WEST HALF OF UPPER MI. WITH ONLY LIGHT TO MODERATE SNOWFALL RATES EXPECTED...AND RELATIVELY LOW SNOW/WATER RATIO VALUES AOB 10/1...ANY ACCUMULATIONS SHOULD REMAIN MAINLY BELOW AN INCH. MODELS SHOWED GREATER DIFFERENCES BY LATER MONDAY AS THE GFS WAS MORE AGGRESSIVE IN DIGGING THE SHRTWV TO THE SOUTH ALLOWING LOW LEVEL WINDS TO VEER MORE NRLY COMPARED TO THE ECMWF. EITHER SOLUTION SUGGESTS THAT WITH DEEP MOISTURE AND CYCLONIC FLOW AND 850 MB TEMPS TO AROUND -6C...LAKE ENHANCED PCPN WILL AFFECT THE NORTH HALF OF UPPER MI THROUGH MON NIGHT. THERE SHOULD ALSO BE ENOUGH LOW LEVEL COLD AIR FOR SOME ACCUMULATING SNOW...ESPECIALLY WHERE UPSLOPE NW TO NNW FLOW PREVAILS. CONFIDENCE IN PCPN/SNOW AMOUNTS IS LOW GIVEN MODEL DIFFERENCES WITH THE DETAILS OF LOW LEVEL WINDS. TUE-THU...WITH THE MEAN LONG WAVE TROUGH POSITION REMAINING OVER THE GREAT LAKES AND ERN CONUS...NW FLOW AND WEAK CLIPPER SHRTWVS ARE EXPECTED TO MOVE THROUGH THE WRN LAKES. THIS WILL BRING PERIODS OF LIGHT PCPN THAT WILL BE ENHANCED BY LAKE SUPERIOR AS 850 MB TEMPS REMAIN IN THE -6C TO -9C RANGE. LOCATIONS FAVORED BY WNW TO NW FLOW ARE LIKELY TO SEE THE GREATEST PCPN CHANCES. SOME ADDITIONAL ACCUMULATING SNOW MAY BE POSSIBLE ALTHOUGH THE AS IS TYPICAL IN EARLY SEASON LAKE EFFECT REGIMES...GRAUPEL WILL LIKELY ALSO BE MIXED WITH ANY RAIN/SNOW SHOWERS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 745 AM EDT FRI OCT 18 2013 A SHORTWAVE MOVING THROUGH THE REGION THIS MORNING WILL CONTINUE TO PRODUCE RAIN SHOWERS AND REDUCED CIGS. EXPECT A SLOW IMPROVING TREND TODAY AND ESPECIALLY TONIGHT AS A WEAK RIDGE QUICKLY MOVES THROUGH. PRECIPITATION AND REDUCED CIGS THEN MOVE BACK IN LATE IN THE FORECAST PERIOD FROM THE W /JUST INCLUDED AT IWD AT THIS TIME/ AS AN UPPER TROUGH MOVES INTO THE AREA. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 507 AM EDT FRI OCT 18 2013 A TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT MOVING ACROSS EASTERN LAKE SUPERIOR TODAY WILL SHIFT EASTWARD TODAY...WITH A BRIEF RIDGE BUILDING BACK IN TONIGHT. WINDS JUST BEHIND THE FRONT MAY BRIEFLY GUST TO 20 TO 30KTS FRIDAY INTO FRIDAY EVENING. DURING THE DAY SATURDAY THROUGH MUCH OF SUNDAY ANOTHER AREA OF LOW PRESSURE WILL APPROACH LAKE SUPERIOR...CAUSING THE PRESSURE GRADIENT TO INCREASE ONCE AGAIN. THIS MAY CAUSE WINDS TO INCREASE TO 20 TO 30 KNOTS...ESPECIALLY SATURDAY NIGHT INTO SUNDAY. MONDAY NIGHT THROUGH TUESDAY...ANOTHER...MORE INTENSE AREA OF LOW PRESSURE...IS SET TO SHIFT INTO THE REGION ALLOWING WINDS TO INCREASE OVER THE LAKE ONCE AGAIN. DURING THIS TIME FRAME WINDS MAY GUST TO NEAR GALES OF 35 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ UPDATE...JLA SHORT TERM...TITUS LONG TERM...JLB AVIATION...TITUS MARINE...TITUS
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
631 AM CDT Fri Oct 18 2013 .SHORT TERM: (Through Late This Afternoon) Issued at 320 AM CDT Fri Oct 18 2013 A weak cold front was moving through the region early this morning, but its only effect across the LSX CWA will be a wind shift from southwest to northwest after fropa. Early morning water vapor imagery along with recent RAP analyses of the 1.5 PVU surface both depict a positively tilted trough over the central CONUS with a couple of stout disturbances sliding down the western side of the trough. Increasing large scale ascent ahead of these vorticity centers will support scattered rain showers from this afternoon into tonight. Since it may take some time to saturate the initially dry air mass, precipitation chances look higher after 19/00z compared to earlier in the afternoon. Kanofsky .LONG TERM: (Tonight through Thursday) Issued at 320 AM CDT Fri Oct 18 2013 Precipitation threat overnight is expected to transition from very light showers during the early evening attempting to stream east- northeast from mid MO, to a broader area of rain developing over the southeast half of the CWA during the overnight hours as upstream shortwave begins to push into mid Mississippi Valley and the large scale ascent is realized over the CWA. Believe the NAM is too far southeast with its QPF in the 06-12z time frame, as almost all over solutions have northern fringes of QPF north of STL. While specifics may be a bit off, the 3 hourly PoP trends from the 03z SREF look very reasonable. This rain should wind down late tonight or very early Saturday morning over our southeast counties as shortwave exits to the east. The brief cool-down in the wake of this feature will quickly give way to WAA in advance of the next shortwave from late Saturday afternoon, with fairly strong warming forecast over most of the CWA from late Saturday night into Sunday. By Sunday afternoon all short range models are forecasting at least 8C 850mb temps over the CWA, with thermal ridge extending from southeast Kansas into ne MO possibly pushing temps to around 10C. Given this trend have upped temps about a category from going forecasts, and most areas should push the 70 degree mark. Heading into the medium range, upper level trof is forecast to deepen over the eastern CONUS in the wake of the aforementioned shortwave, and this will bring even colder air into the region for the start of the new week. The airmass that pushes into the area Monday night and Tuesday will be the coldest so far of this fall, and its certainly possible that the growing season could come to an end in some areas either Tuesday or Wednesday morning. However, the frost threat will depend on timing of surface ridge and any clouds that advect into the region on the fairly dirty northwest flow, and specifics with both the high and clouds are not clear at this time. Based on progged 850mb temps it appears that during the Tuesday-Thursday time frame highs will only be in the 50s with lows in the 30s. At this time have kept PoPs in the slight chance range with the passage of the cold front Sunday night and Monday due to very limited moisture. Have also continued slight chance PoPs over the area on Tuesday night as another weak shortwave drops into the area. Truett && .AVIATION: (For the 12z TAFs through 12z Saturday Morning) Issued at 620 AM CDT Fri Oct 18 2013 MVFR ceilings are possible at KUIN for the next couple of hours based on upstream satellite and METAR trends however conditions should return to VFR by mid-morning. VFR conditions are expected elsewhere along with increasing clouds during the day. Light rain showers will spread eastward towards the terminals tonight, however no cig/vis restrictions are forecast at this time due to the initially dry air mass and the anticipated light rain intensity. Specifics for KSTL: VFR through at least the first 6 hours and probably longer, although clouds will be increasing throughout the day. Light rain showers are expected to develop across central MO later tonight and spread eastward towards KSTL. No cig/vis restrictions are forecast at this time due to the initially dry air mass and the anticipated light rain intensity. Kanofsky && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
627 AM CDT Fri Oct 18 2013 .SHORT TERM...(Today through Sunday Night) Issued at 405 AM CDT FRI OCT 18 2013 Long wave troughing persisted across the central CONUS early this morning, and this pattern appears locked in for the next couple of weeks. Embedded within the the large scale dip, the third in a recent sequence of shortwave impulses was tracking southward through Wyoming, and remains on track to target the southern half of the CWA later today. Front Range, CO radar shows an impressive band of snow expanding over NE Colorado, while satellite imagery shows mid cloud rapidly expanding eastward across srn Nebraska and most of Kansas. These trends suggest that the axis of strong elevated frontogenesis will likely come in a bit further north than earlier progged. This is supported by a northward shift in the 00Z model solutions and more recently the hourly RAP output. For today, cloud cover will quickly overspread the CWA from west to east this morning. Forecast soundings and model cross sections show a rapid top- down saturation as sloped 700-500mb frontogenesis increases in response to large scale height falls isentropic ascent. Despite clear skies presently, precipitation could begin over ern KS/west central MO as early noon. As discussed yesterday, the sub- cloud layer will initially be very dry while 850-700mb temperatures fall sharply as the shortwave approaches. In fact, if not for the boundary layer, we would likely be dealing with wet snow! Nonetheless, once the rain begins, surface temps will immediately respond to diabatic cooling and fall back through the 40s. Hourly temperatures reflect a non-diurnal curve for the afternoon. Precipitation should reach a local maximum between 18-00Z, steadily shifting southward with time as a small 700-500mb jet streak develops and shifts the axis of greatest mid level forcing. QPF amounts will average between one and two tenths of an inch, generally along and south of I-70. The mid level trough axis will quickly pivot across the CWA overnight, with skies gradually clearing from west to east. Temps will fall into the mid 30s by daybreak, and although conditions are not optimal for a widespread frost, the moist boundary layer and diminishing winds could enhance the potential. Next shift may want to consider headlines for all or portions of the region tonight. After a chilly day Saturday, strengthening west winds will develop south of a progressive shortwave trough moving across the Upper Midwest. Strong low level warm advection will begin Saturday night and continue into Sunday, with a deep layer Chinook component expected to rapidly spread some mild air eastward across the Plains. Given upward trends in 850mb temp progs, have bumped highs into the upper 60s to around 70 for Sunday, and made a significant increase to the surface winds/gusts over the srn half of the CWA. A dry cold front will sweep across the area Sunday night, leading to a very challenging low temperature forecast that hinges entirely on where the front ends up by 8AM. Current forecast projects a near 15 degree gradient from mid 30s along the Iowa border to near 50 across mid Missouri, and significant adjustments remain possible. .LONG TERM...(Monday through Thursday) Issued at 403 AM CDT FRI OCT 18 2013 Later half of the forecast will continue the cool trend as negative height anomalies persist across the Lower Missouri River Valley through much of next week. As Monday arrives a significant trough will be digging in across the center of the nation providing cold air from the Canadian Plains with plenty of opportunity to rush south through the northern and central Plains. Resulting cold air with the northwest flow will keep temperatures ranging below normal through the week. This is supported by 850mb model output which advertises subzero centigrade temperatures sweeping into the region Monday, and again Wednesday behind a small shortwave trough zipping through the flow. This should make for some cool fall conditions next week with highs only the 50s expected Monday through Wednesday. As for overnight low, a bit of a frost might be in the offing. Overnight lows will drop into the 30s Tuesday, Wednesday and Thursday mornings. Currently, areas along and north of highway 36 look to have the greatest chance for seeing repeated frost. Otherwise, have included a silent slight chance for showers Wednesday into Thursday. Models continue to advertise a shortwave trough zipping through the northwest flow mid-week, providing a little reinforcing shot of cold air for Thursday mornings lows. Models might be over doing the amount of moisture, thus confusing low cloud cover with QPF, though disturbances in the northwest flow often squeeze some light precipitation out across eastern Kansas or Missouri. Have left the silent slight chance POPs characterized as showers for now, though if confidence in Tuesdays quick shortwave improves some consideration might be needed for including snow in the precipitation forecast. && .AVIATION...(For the 12Z TAFS through 12Z Saturday Morning) Issued at 626 AM CDT FRI OCT 18 2013 VFR conditions will great the last day of the work week, however these conditions might deteriorate as we transit the morning hours as showers spread east across the region. Currently showers are expect from east central Kansas through central Missouri around noon today. This leaves the terminals in Kansas City with the highest potential to see some rain with ceilings floating around the high end of the MVFR range. Otherwise, northwest winds will adjust more to the southwest behind the storms system that moves through today. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ SHORT TERM...Bookbinder LONG TERM...Cutter AVIATION...Cutter
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
550 AM MDT FRI OCT 18 2013 .AVIATION... 12Z TAF CYCLE SOME LOW STRATUS CLOUDS AND PATCHY FOG HAVE DEVELOPED AGAIN IN THE EAST CENTRAL TO SOUTHEASTERN PLAINS OF NEW MEXICO EARLY THIS MORNING. MVFR TO IFR CEILINGS AND VISIBILITIES SHOULD STAY EAST OF A KROW TO KCVS LINE WHERE LOW LAYER MOISTURE HAS BEEN TRANSPORTED. IN THE NORTHEAST CORNER OF THE STATE A BACK DOOR COLD FRONT IS INVADING WITH GUSTY WINDS NOTED ALONG AND BEHIND THE BOUNDARY. ALSO...SOME LOWER CEILINGS OF GENERALLY 2000 TO 3000 FEET ARE ACCOMPANYING THE FRONT. THESE CLOUDS IN THE NORTHEAST MAY PERSIST AND EXPAND OVER THE REMAINDER OF THE NORTHEASTERN QUADRANT OF NEW MEXICO THROUGH THE MID AFTERNOON WHILE THE LOWER STRATUS CLOUDS AND FOG IN EAST CENTRAL AND SOUTHEASTERN AREAS SHOULD DISSIPATE BEFORE 18/1800UTC. VFR CONDITIONS WILL PREVAIL ELSEWHERE WITH MOSTLY CLEAR SKIES. 52 && .PREV DISCUSSION...330 AM MDT FRI OCT 18 2013... SFC LOW/TROUGH ACROSS FAR EAST CENTRAL NM AND INTO THE ADJACENT PORTION OF TX HAS CIRCULATED LOW LEVEL MOISTURE INTO SE NM WITH ATTENDANT LOW CLOUDS/FOG OVER LEA/EDDY AND SE ROOSEVELT COUNTIES...WHICH IS FARTHER WEST THAN WAS INDICATED 24 HRS AGO. EXPECT THIS WILL MAKE A LITTLE MORE PROGRESS NORTH AND WWD BEFORE THE COLD FRONT...CURRENTLY FROM CAO TO RTN...AND WITH IT/S STRATUS...PUSHES FARTHER SOUTH. RUC INDICATES THE MOISTURE IN THE SOUTHEAST SHOULD EXIT BY MID MORNING WHILE THE STRATUS CONTINUES TO INVADE THE NE AND TO SOME EXTENT THE EAST CENTRAL. TODAY/S AREAL COVERAGE OF POPS DIDN/T CHANGE MUCH FROM PREVIOUS MODEL RUNS. FORECAST HIGHS HOWEVER DID COOL SEVERAL DEGREES IN THE NORTHEAST AND EAST CENTRAL NO DOUBT IN PART TO THE EXTENSIVE LOW CLOUDS THAT MAY LINGER THROUGH EARLY/MID AFTERNOON ACCORDING TO THE RUC. THE AREA FROM RATON TO CLAYTON MAY NOT GET ANY WARMER THAN MID 40S...WHICH IS 20 TO 25 DEGREES BELOW NORMAL IF THE GUIDANCE IS CLOSE. OVERALL HIGHS TODAY RANGE FROM NEAR NORMAL FAR SOUTHWEST TO 10 TO 15 DEGREES BELOW AVERAGE FAR NORTHWEST TO THE FAR SOUTHEAST. THE COOLER THAN AVERAGE HIGHS SET THE STAGE FOR POTENTIAL FOR NEAR TO BELOW FREEZING LOWS TONIGHT. GUIDANCE FOR PORTIONS OF THE EAST CENTRAL CLOSER TO THE TX BORDER AND ROW AREAS HAS COOLED A COUPLE MORE DEGREES...SO A FREEZE WATCH WILL BE ISSUED. SOME LOW LEVEL MOISTURE MAY BE PARKED ALONG THE EAST SLOPES OF THE CENTRAL MT CHAIN THIS EVENING BUT DEWPOINTS STILL EVENTUALLY LOWER SUFFICIENTLY FOR THE THREAT OF A FREEZE. MODELS NOW INDICATE AT LEAST SOME POTENTIAL FOR AN EAST WIND TO BREAK INTO THE MIDDLE RGV THIS EVENING...WHICH COMPLICATES A FREEZE/NO FREEZE DECISION THAT MUCH MORE ESPECIALLY IN THE ABQ METRO. CURRENT THOUGHTS ARE THE WIND COULD DIMINISH AFTER MIDNIGHT...SO DECIDED TO ISSUE A FREEZE WATCH FOR THE MIDDLE AND LOWER RGV AS WELL AS FOR THE UPPER TULAROSA VALLEY...WHERE SOME LOCALES HAVE NOT YET FROZEN. FOR THE REST OF THE WEEKEND...A WARMING TREND WILL COMMENCE WITH HIGHS ACHIEVING NEAR NORMAL STATUS SUNDAY. ANOTHER FRONT COULD ARRIVE IN THE EASTERN PLAINS AS SOON AS LATE SUNDAY...SO HIGHS WILL BE KNOCKED DOWNWARD MONDAY. THIS FRONT LOOKS MORE LIKELY TO PRODUCE AN EAST WIND INTO THE RGV EARLY MONDAY. EXTENDED FORECAST MODEL TRENDS FOR MID TO LATE NEXT WEEK LEAN TOWARDS MORE OF A RIDGE OVER NEW MEXICO. LATEST ECMWF DEPICTS A DECENT SFC HIGH INVADING ERN NM DESPITE THE RIDGE WHILE THE GFS LOCATES IT WELL TO THE EAST...WREAKING HAVOC ON FORECAST TEMPERATURE DECISIONS. BOTH GFS AND ECMWF INDICATE A WEAK DISTURBANCE TRACKING INTO WRN NM FROM THE WEST AROUND THURSDAY OF NEXT WEEK...NOT CONFIDENT AT ALL IT WILL AMOUNT TO MUCH. IN ANY CASE WENT CLOSER TO THE ECMWF SOLUTION FOR TEMPS AND WITH A GFS/ECMWF BLEND FOR POPS. .FIRE WEATHER... COOLER AIR WILL INVADE NEW MEXICO TODAY AS NORTHWEST FLOW ALOFT DRAGS A TROUGH INTO THE STATE ALONG WITH A BACK DOOR SURFACE FRONT. THE PLAINS WILL OBSERVE THE SHARPEST TEMPERATURE DIFFERENTIAL FROM YESTERDAY ALONG WITH GUSTY NORTHEAST WINDS THROUGH THE DAY AS THE FRONT SPILLS IN. THE CENTRAL TO WESTERN ZONES WILL ALSO BECOME BREEZY TO WINDY WITH A NORTHWESTERLY DIRECTION. SURFACE GRADIENT APPEARS A BIT STRONGER THAN PREVIOUS MODEL RUNS WERE ADVERTISING...SO FORECAST SPEEDS WERE INCREASED TO REFLECT THIS. VENTILATION RATES LOOK TO REMAIN GOOD TO EXCELLENT WITH THESE STRONGER BOUNDARY LAYER BREEZES...BUT WINDS DO NOT APPEAR TO BE CRITICALLY HIGH. DEWPOINTS DROP INTO THE LOWER TEENS AND SINGLE DIGITS IN THE WEST CENTRAL TO SOUTHWESTERN ZONES OF THE FORECAST AREA THIS AFTERNOON...DROPPING MINIMUM RH TO 12 TO 15 PERCENT. THIS AREA OF CRITICALLY LOW RH WILL NOT BE JUXTAPOSED OVER THE AREA WHERE THE STRONGEST WINDS WILL BE...AND THE COOLER TEMPERATURE REGIME DOES NOT FIT INTO THE MOLD OF A CRITICAL FIRE WEATHER EVENT EITHER. MAX TEMPERATURES WILL RUN ABOUT 8 TO 20 DEGREES BELOW NORMAL IN MOST AREAS TODAY. BETTER RH RECOVERY IS EXPECTED TONIGHT WITH COOLER TEMPERATURES. DEWPOINTS MAY LOWER A BIT IN THE PLAINS BY TONIGHT...BUT THEY WILL ACTUALLY RISE A BIT IN THE CENTRAL AREAS OF THE STATE. THIS WILL ALLOW MOST OF THE NORTHERN AND EASTERN TIERS OF THE STATE TO OBSERVE EXCELLENT RH RECOVERY WHILE CENTRAL TO WESTERN ZONES STAY IN THE FAIR TO GOOD CATEGORIES. ANOTHER SIGNIFICANT ASPECT OF TONIGHT/S FORECAST WILL BE THE POTENTIAL FOR FREEZING TEMPERATURES IN MUCH OF THE EAST CENTRAL PLAINS WHERE THE FREEZING MARK HAS YET TO BE REACHED. THIS WILL EXACERBATE FINE FUEL CURING. THERE WILL ALSO BE POTENTIAL FOR FREEZING TEMPERATURES ALONG THE MIDDLE RIO GRANDE AND TULAROSA VALLEYS...PRIMARILY IN THE LOWEST ELEVATIONS. SOME OF THESE VALLEY AREAS HAVE FLIRTED WITH FREEZING ON A COUPLE OF OCCASIONS THIS SEASON...BUT A WIDESPREAD HARD FREEZE HAS STILL NOT HAPPENED. NORTHWEST FLOW WILL NOT BE AS STRONG ON SATURDAY...AND ONLY SOME ISOLATED BREEZY TO WINDY CONDITIONS ARE EXPECTED OVER THE CENTRAL HIGHLANDS. TEMPERATURES WILL WARM A FEW DEGREES IN MOST OF THE FORECAST AREA AND SEVERAL DEGREES IN THE NORTHEASTERN PLAINS...BUT STILL DAYTIME HIGHS IN ALL AREAS WILL FALL JUST SHY OF CLIMATOLOGY. LOWEST DEWPOINTS WILL STAY CONFINED TO WEST CENTRAL NM SATURDAY...BUT THESE WILL MIX AND ADVANCE EASTWARD INTO SUNDAY. THIS WILL SPREAD SOME CRITICAL RH OVER THE CENTRAL HIGHLANDS WHERE A BRIEF BOUT OF CRITICAL WINDS WILL ALSO DEVELOP SUNDAY AFTERNOON. THE NEXT COLD FRONT WILL ARRIVE SUNDAY NIGHT AND INTO MONDAY MORNING. THIS BOUNDARY WILL LIKELY ADVANCE BEYOND THE CENTRAL MOUNTAIN CHAIN AND INTO THE RIO GRANDE VALLEY...PRODUCING SOME GUSTY WINDS ALONG THE BOUNDARY AND THROUGH CENTRAL GAPS/CANYONS WHILE TEMPERATURES PLUMMET BACK BELOW AVERAGE. OVERALL A DRIER AND MORE TRANQUIL PATTERN IS EXPECTED THROUGH TUESDAY AND WEDNESDAY OF NEXT WEEK...HOWEVER THERE IS SOME UNCERTAINTY REGARDING ANOTHER POTENTIAL FRONT. FORECAST MODELS HAVE DIFFERING NOTIONS ON HOW THE UPPER RIDGE WILL BREAK DOWN...AND MODELS HISTORICALLY HAVE SOME NOTORIOUS DEFICIENCIES IN THESE HIGH AMPLITUDE PATTERNS. 52 && .ABQ WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR THE FOLLOWING ZONES...NMZ519-520-525-533>538. && $$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1127 AM EDT FRI OCT 18 2013 .SYNOPSIS... HIGH PRESSURE WILL CONTINUE TO BUILD IN THIS AFTERNOON. HOWEVER...THE FAIR WEATHER WILL BE SHORT-LIVED AS THE WEATHER PATTERN WILL BE UNSETTLED OVER THE NEXT WEEK AS A SERIES OF FRONTS MOVE THROUGH THE REGION. && .NEAR TERM /THROUGH TONIGHT/... CLOUDS ARE DISSIPATING AND SLIDING ENE. RH PROGS DO INDICATE A GRADUAL DRYING...AND HAVE FOLLOWED RUC SKY FOR THE NEXT 12 HRS. MID-LAKE BAND SHOULD REMAIN JUST TO THE NORTH OF THE NY BORDER. SFC HIGH TO THE SOUTH WILL EAT AWAY AT THE CLOUDS. BUT UPSLOPE FLOW COMPONENT AND PROXIMITY TO THE HIGH AND RELATED SUBSIDENCE WILL DICTATE THE DEGREE AND RAPIDITY OF CLEARING. WELL MIXED MDL SOUNDINGS ARE SUPPORTIVE OF WEST WINDS BTWN 10-20KTS...BUT THESE SHOULD GET A LITTLE LIGHTER ON THE WHOLE DURING THE LATE AFTN. TEMPS STILL EXPECTED TO TOP OUT IN THE M50S-M60S...PRETTY CLOSE TO NORMAL FOR MID OCT. THE OVERNIGHT WILL BE FAIR AND DRY WITH JUST A FEW HIGH CLOUDS STARTING TO INVADE THE NW TOWARD MORNING. IT WILL NOT BE PARTICULARLY COLD...WITH LOWS IN THE 40S BEING NEAR OR EVEN SLIGHTLY WARMER THAN NORMAL. && .SHORT TERM /SATURDAY/... A NEW COLD FRONT WILL APPROACH THE REGION SATURDAY SPREADING MORE SHOWERS OUR WAY...ESPECIALLY LATER IN THE MORNING INTO THE AFTERNOON. THE ATMOSPHERE WILL NOT HAVE MUCH TIME TO RECOVER SO THE FRONT WILL NOT HAVE A GREAT DEAL OF MOISTURE TO WORK WITH. MARGINALLY STEEP MID LEVEL LAPSE RATES SHOULD PROVIDE JUST ENOUGH INSTABILITY TO GIVE MOST AREAS SOME LIGHT SHOWERS. ENSEMBLE QPF SHOWS AMOUNTS GENERALLY .10" OR LESS WITH THE NW HAVING A LOW PROBABILITY OF AS MUCH AS .25" IN SOME SPOTS. THE MAIN THING TO BE SAID OF THE NEXT COLD FRONT IS THAT WILL BE THE HARBINGER OF A COOLER MORE UNSETTLED PATTERN SETTING UP FOR THE NEXT WEEK OR SO. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... A SIGNIFICANT PATTERN CHANGE IS IN STORE FOR THE REGION DURING THE EXTENDED PERIOD WITH MUCH OF THE EAST COAST COMING UNDER THE INFLUENCE OF AN ANOMALOUSLY DEEP UPPER TROUGH THAT WILL MOVE OUR WAY OUT OF THE GR LAKES. A STRONG TYPHOON THAT PASSED EAST OF JAPAN SEVERAL DAYS AGO IS NOW BEING ABSORBED INTO THE FLOW OVER THE NORTHERN PACIFIC...HELPING PUMP UP THE WESTERN NORTH AMERICAN RIDGE. THIS WILL HELP DELIVER INCREASINGLY CHILLY AIR DOWN INTO FIRST THE UPPER MID WEST AND EVENTUALLY INTO THE LOWER LAKES AND LOCAL AREA BY THE TUESDAY-WEDNESDAY TIMEFRAME. PRECIP CHANCES WILL BE MANY...BUT MAINLY FROM MOISTURE-STARVED CLIPPER TYPE SYSTEMS. TIMING WITH THESE ALWAYS PRESENTS A PROBLEM...BUT WITH THE COLD AIR EXPECTED TO MOVE OUR WAY...ANY LIGHT SHOWERS THAT FALL DURING THE COLD PART OF THE DAY COULD ACTUALLY MIX WITH SOME WET SNOW. AN EARLY SEASON REMINDER OF WHAT IS IN STORE. && .AVIATION /15Z FRIDAY THROUGH TUESDAY/... ONE THICKER/LONGER BAND OF CLOUDS ALONG THE MIDDLE OF THE LAKE AND NOW SLIDING TO THE NORTH. CLOUD BASES NOT LIFTING ALL THAT MUCH WITH STRONG COLD ADVECTION AND ONLY BALANCED SFC HEATING. OVERALL AREA/COVERAGE OF CLOUDS IS ON THE DECREASE THOUGH. EXPECT VFR FOR UNV - AND PERHAPS JST AS THEY LOSE THEIR THICKEST CLOUD COVER. DIURNAL CU IS POPPING TO PARTIALLY REPLACE THE STRATUS THOUGH. SHOULD STAY BREEZY THROUGH THE DAY WITH THE SFC HIGH TO OUR SOUTH AND WESTERLIES JUST AS CLOSE. ANOTHER COLD FRONT WILL BRING A CHANCE OF SHOWERS TO THE AREA ON SATURDAY INTO SUNDAY MORNING. GUSTY WINDS AND LAKE EFFECT CLOUDS WILL BE LIKELY EARLY SUNDAY...BULK OF THE SHOWERS WILL BE NORTH OF OUR AREA...PERHAPS AN ISSUE FOR MAINLY N PA...SPOTS LIKE BFD EARLY. THE NEXT COLD FRONT MOVES IN LATE MONDAY INTO TUE. THIS AIRMASS WILL BE COLDER AND DEEPER...THUS MORE OF THE WAY OF LAKE EFFECT CLOUDS AND SHOWERS WILL PERSIST INTO MID WEEK. OUTLOOK... SAT...BECOMING CLOUDY WITH SHOWERS...MVFR AND POCKETS OF IFR. SUN...MVFR CIGS/CHC OF LK EFFECT RAIN SHOWERS MAINLY NW. VFR ELSEWHERE. MON...NO SIG WX. TUE...FROPA. MVFR/IFR POSS DUE TO SHOWERS/CLOUDS...ESP NW. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...DANGELO SHORT TERM...LA CORTE LONG TERM...LA CORTE AVIATION...DANGELO/MARTIN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1134 AM MDT FRI OCT 18 2013 .UPDATE... ISSUED AT 732 AM MDT FRI OCT 18 2013 UPDATED FRONT END OF FORECASTS TO REFLECT CURRENT OBSERVATIONS AND TRENDS. NO MAJOR CHANGES TO FORECAST AT THIS TIME. LW && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 527 AM MDT FRI OCT 18 2013 ...HIT AND RUN STORM ON THE WAY... IT`S ON OUR DOORSTEP. THE SHORTWAVE THAT HAS BEEN HEADED OUR WAY IS ABOUT TO ARRIVE. MULTIPLE LATE NIGHT TWEETS INDICATE SNOW HAS SPREAD QUICKLY SOUTH ACROSS THE NORTHERN FRONT RANGE URBAN CORRIDOR AND NORTHEAST PLAINS THIS MORNING. RADAR AND SURFACE REPORTS INDICATE THAT SNOW HAS ALREADY SPREAD INTO THE CENTRAL MOUNTAINS...INCLUDING LEADVILLE AND MONARCH PASS...AND IT IS JUST NOW CROSSING THE PALMER DIVIDE INTO NORTHERN TELLER AND NORTHERN EL PASO COUNTIES. ALL FORECAST MODELS AGREE THAT SNOW WILL MOVE INTO TELLER AND EL PASO COUNTIES THIS MORNING...WITH A MIXTURE OF RAIN AND SNOW SHOWERS SPREADING SOUTH ACROSS THE REST OF THE EASTERN MOUNTAINS AND PLAINS. THE GFS...AND TO A LESSER EXTENT...THE NAM HAVE BEEN GRADUALLY TRENDING BACK TOWARD BETTER CHANCES FOR PRECIPITATION OVER THE EASTERN MOUNTAINS AND PLAINS THAN THEY WERE 24 HOURS AGO. ADDITIONALLY...SHORT RANGE FORECASTS OFF OF THE HIGH RESOLUTION MODELS...INCLUDING THE HRRR AND THE WRF...ALSO SHOW AT LEAST SOME PRECIPITATION SPREADING SOUTH ACROSS MOST OF THE EASTERN MOUNTAINS AND PLAINS THIS MORNING. NONE OF THE MODELS HAVE ANYTHING VERY HEAVY...BUT THEY DO HAVE SOME LIGHT TO LOCALLY MODERATE AMOUNTS. RIGHT NOW...BEST BET IS FOR 1 TO 3 INCHES OF SNOW OVER THE CENTRAL MOUNTAINS AND PIKES PEAK...LOCAL 1 TO 2 INCHES AMOUNTS ACROSS TELLER AND EL PASO COUNTIES...AND GENERALLY AN INCH OR LESS ACROSS THE REST OF THE EASTERN MOUNTAINS AND PLAINS. PRECIP BELOW 5500 FEET WILL PROBABLY COME AS A MIXTURE OF RAIN AND SNOW SHOWERS...WHICH SHOULD HELP TO LIMIT ACCUMULATIONS. ELEVATIONS ABOVE 5500 FEET WILL SEE MOSTLY SNOW AND THE BEST CHANCES FOR ACCUMULATION. SECOND ONLY TO THE PIKES PEAK REGION...THE FAR EASTERN PLAINS ALONG THE KANSAS BORDER WILL SEE SOME OF THE BETTER ODDS FOR PRECIPITATION TODAY. LIGHT SNOW IS ALREADY FALLING AT BURLINGTON AND RADAR SHOWS DEVELOPING PRECIPITATION OVER NORTHEAST KIOWA COUNTY AT THIS TIME. THIS DEVELOPMENT SHOULD CONTINUE SOUTHWARD THROUGH THE MORNING INTO THE EARLY AFTERNOON HOURS. TEMPERATURES WILL BE A BIT BORDERLINE FOR MUCH IN THE WAY OF SNOW ACCUMULATION...BUT COULD BE SOME SPOTTY LIGHT AMOUNTS...ESPECIALLY ON GRASSY AREAS. EVERYTHING SHIFTS EAST OF THE AREA AFTER ABOUT 2 OR 3 IN THE AFTERNOON...SETTING THE STAGE FOR ANOTHER COLD NIGHT ACROSS SOUTHERN COLORADO. A FREEZE WATCH REMAINS IN EFFECT FOR A LARGE PART OF SOUTHEAST COLORADO FOR TONIGHT. LW .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 527 AM MDT FRI OCT 18 2013 NOT MANY METEOROLOGICAL LONGER TERM ADJUSTMENTS NEEDED FROM EARLIER FORECAST THINKING AS A GENERALLY DRY AND MILD LONGER TERM PATTERN IS EXPECTED TO DEVELOP OVER THE FORECAST DISTRICT. FROM SATURDAY INTO THURSDAY...LATER COMPUTER SIMULATIONS CONTINUE TO SUGGEST THAT A GENERALLY DRY AND MILD NORTHWESTERLY TO NORTHERLY UPPER FLOW PATTERN WILL BE NOTED OVER THE CWFA THANKS TO AN UPPER RIDGING PATTERN BUILDING OVER THE WESTERN UNITED STATES DURING THIS TIME-FRAME. AT THIS TIME...IT APPEARS THAT THE HIGHEST POTENTIAL FOR SHOWER ACTIVITY DURING THE LONGER TERM OVER THE FORECAST DISTRICT WILL OCCUR FROM LATER SUNDAY INTO MONDAY...ESPECIALLY OVER NORTHERN SECTIONS AS AN UPPER DISTURBANCE INTERACTS WITH A SURFACE NORTHERLY TO NORTHEASTERLY SURGE. MAXIMUM AND MINIMUM TEMPERATURES DURING THE LONGER TERM SHOULD BASICALLY RUN NEAR TO A FEW DEGREES ABOVE LATE OCTOBER CLIMATOLOGICAL AVERAGES...ALTHOUGH TEMPERATURES BELOW SEASONAL AVERAGES ARE ANTICIPATED MONDAY IN WAKE OF NORTHERLY/NORTHEASTERLY SURGE AND UPPER DISTURBANCE. FINALLY...LOW-GRADE GRADIENT WINDS ARE STILL ANTICIPATED OVER THE MAJORITY OF THE FORECAST DISTRICT DURING THE LONGER TERM. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1130 AM MDT FRI OCT 18 2013 VFR CONDITIONS ARE EXPECTED THE REST OF THE DAY AT KCOS AND INTO SATURDAY MORNING...ALTHOUGH SOME SCATTERED LOW CLOUDS WILL STILL BE IN THE VCNTY THIS AFTERNOON. IFR CONDITIONS AT KPUB WILL TRANSITION TO VFR AS THE CLOUD COVER DECREASE THIS AFTERNOON. KALS WILL CONTINUE TO HAVE VFR CONDITIONS THROUGH SATURDAY MORNING...WITH SOME GUSTY NW WINDS EXPECTED TO CONTINUE THROUGH THE AFTERNOON. && .PUB WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR COZ083-086-089-093>099. && $$ UPDATE...LW AVIATION...28
AREA FORECAST DISCUSSION
NWS DES MOINES IA
322 PM CDT FRI OCT 18 2013 .SHORT TERM /TONIGHT/... ISSUED AT 323 PM CDT FRI OCT 18 2013 IN A NEAR REPEAT OF YESTERDAY AFTERNOONS FORECAST...ANOTHER 500 MB SHORTWAVE EMBEDDED IN THE MEAN CENTRAL NORTH AMERICAN LONGWAVE TROUGH IS POISED TO TRACK THROUGH IOWA LATE TONIGHT AND INTO TOMORROW MORNING. AS WITH ITS PREDECESSOR...FORCING AND MOISTURE WILL BE SPARSE AND ANY RAIN SHOWERS OVERNIGHT WILL BE CONFINED TO NORTHERN IOWA. THIS SCENARIO WAS HANDLED WELL BY THE HIGH RES WRF ARW AND RAP...THUS USED A BLEND OF THESE TWO MODELS FOR THE PRECIPITATION FORECAST. A SECOND IMPULSE/VORT MAX SLIDES DOWN THE REAR FLANK OF THE LONGWAVE TROUGH IN WESTERN MINNESOTA AND NORTHWEST IOWA TOWARDS THE END OF THE PERIOD. MOISTURE PROFILES ARE SLIGHTLY MORE CONDUCIVE FOR RAINFALL AND HAVE INCREASED POPS ACCORDINGLY IN THE NORTHWEST TOWARDS 12Z SAT. 290 TO 300K ISENTROPIC ACCENT GENERATED A BAND RAIN AND SNOW ACROSS KANSAS AND NORTHERN MISSOURI TODAY. THE ASSOCIATED SHIELD OF CIRROSTRATUS AND ALTOSTRATUS CLOUDS PROPAGATED INTO IOWA THIS MORNING AND PUT A DAMPER ON HIGHS ACROSS THE SOUTHERN HALF OF THE CWA. THIS SYSTEM WILL PULL ENE THIS EVENING AS THE UPPER LEVEL TROUGH DIGS INTO THE CENTRAL PLAINS. THERE IS SOME UNCERTAINTY WITH HOW MUCH OF THE CLOUD COVER OVER SOUTHERN IOWA WILL CLEAR OUT BETWEEN THE 06 AND 12Z TIMEFRAME. BOTH THE NAM AND RAP SOUNDINGS HINT AT SOME CLEARING TOWARDS MORNING...SO LOWERED MIN TEMPS IN THE NISH VALLEY AND OTHER PORTIONS OF SOUTHWEST IOWA. .LONG TERM /SATURDAY THROUGH FRIDAY/... ISSUED AT 323 PM CDT FRI OCT 18 2013 BROAD LONG WAVE TROF WILL REMAIN ENTRENCHED ACROSS THE EASTERN HALF OF THE UNITED STATES DURING THIS FORECAST PERIOD. THEREFORE...BELOW NORMAL TEMPERATURES ARE EXPECTED FOR MUCH OF THE NEXT WEEK. THERE WILL ALSO BE THREATS FOR LIGHT PRECIPITATION FROM TIME TO TIME AS SYSTEMS PASS THROUGH THE STRONG NORTHWEST FLOW. FIRST WEAK SYSTEM GLANCES THE NORTH TOMORROW MORNING ALTHOUGH THE BULK OF THE FORCING WILL REMAIN NORTH OF IOWA. HAVE CONTINUED THE THREAT FOR SOME ISOLATED/SCATTERED SHOWERS IN THE MORNING BUT WITH SUBSIDENCE ARRIVING BY AFTERNOON...SHOULD SEE ANY ACTIVITY QUICKLY ENDING. WARM ADVECTION INTO SUNDAY WILL MAKE IT THE WARMEST DAY OVER THE NEXT WEEK. THE WARMER AIR IS AHEAD OF THE NEXT SYSTEM DIVING SOUTHEAST INTO THE REGION. ONCE AGAIN...THE FORCING ASSOCIATED WITH THIS SYTEM REMAINS NORTH OF IOWA WITH ANY PCPN THREAT RESIDING NEAR THE MINNESOTA BORDER. STRONG COLD ADVECTION WILL ARRIVE BY LATE IN THE DAY WITH A MUCH COLDER AIRMASS BECOMING ESTABLISHED ACROSS THE STATE ON MONDAY. ONE FINAL SYSTEM DROPS SOUTHEAST TOWARD THE STATE LATE MONDAY NIGHT INTO TUESDAY. THE EURO IS MOST AGGRESSIVE WITH SATURATION AND LIFT ACROSS IOWA WITH A FEW TENTHS OF PCPN ON TUESDAY. GIVEN RELATIVELY COLD THERMAL PROFILES DURING THIS EVENT...WOULDNT BE SURPRISED TO SEE SOME SNOW MIXED WITH RAIN WITH STRONG DYNAMICAL COOLING SUGGESTED BY THE LIFT. THE COLDER AIRMASS WILL THEN REMAIN ESSENTIALL IN PLACE THROUGH THE END OF NEXT WEEK. THIS SHOULD EFFECTIVELY END THE GROWING SEASON ACROSS CENTRAL IOWA FOR THOSE LOCATIONS THAT HAVENT ALREADY SEEN A FREEZE. && .AVIATION...18/18Z ISSUED AT 1240 PM CDT FRI OCT 18 2013 VFR CONDITIONS SHOULD PREVAIL OVER CENTRAL IOWA THROUGH MUCH OF THE TAF PERIOD. A FRONT PUSHING SOUTHEAST MIGHT BRING SOME LOW CLOUDS AND SHOWERS TO NORTHERN IOWA TOMORROW MORNING...BUT DRIER AIR NEAR THE SURFACE SHOULD LIMIT THE EXTENT OF LOWER CEILINGS. WINDS WILL REMAIN OUT OF THE WEST TO NORTHWEST THROUGH THE PERIOD WITH DIURNAL FLUCTUATIONS IN WIND SPEED. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...SKOW LONG TERM...COGIL AVIATION...SKOW
AREA FORECAST DISCUSSION
NWS TOPEKA KS
307 PM CDT Fri Oct 18 2013 .SHORT TERM...(This Evening through Saturday) Issued at 307 PM CDT FRI OCT 18 2013 20z water vapor imagery shows a shortwave propagating across the state. The forcing from this wave has brought widespread rain and snow with some light accumulations across portions of north central KS. Surface obs indicate a mesoscale high is centered over southwest KS. Areas where precipitation has persisted through the day have had temps holding steadily in the 30s. For tonight the forcing from the upper wave should move to the east of the forecast area with precipitation coming to an end over east central KS by mid evening. Snow is likely to remain mixed with the precip, but since the intensity of the snowfall has been light due to partial melting as it falls. accumulations should remain mainly trace amounts. As the upper wave moves east, subsidence should increase allowing skies to become mostly clear. Models do not show a great deal of cold air advection overnight, but with dewpoints in the lower 30s and 20s expected to move in think radiational cooling could drop overnight lows to around 30 for most areas. Because of this have issued a freeze warning. Saturday looks to be mostly sunny and warmer as northwest flow aloft is free of shortwaves and westerly low level flow advects warm air back into the region. All the models are showing 850 temps in the +6 to +7C range with good mixing of the boundary layer. This should yield highs in the lower 60s east to the mid 60s across north central KS. .LONG TERM...(Saturday Night through Friday) Issued at 307 PM CDT FRI OCT 18 2013 There were not many changes made to the medium and extended range periods, though this is not because of high confidence. Strong north-northwest flow over the central portions of the nation will be the rule through these periods, with minor alterations in trajectories of these winds and timing of waves moving through the flow creating opportunities for much cooler northerly flow tapping airmasses from Alaska or northern Canada, or warmer northwest flow allowing modified continental air to push in from the west. MOS temperature output from both the GFS and ECMWF ensembles showing this issue with large spreads. Sunday still looking to be the warmest with west to southwest low level flow from Saturday night into at least early Sunday ahead of a cold front. Cold air advection is not terribly strong immediately behind the front so despite northwest winds taking hold over northwestern areas by mid afternoon and considerable high clouds, still expect middle 60s to around 70 for maxes. Will keep temps a bit cooler than normal otherwise. Lows still have the potential to be in the frost/freeze range, mainly Monday night and Tuesday night. There is good agreement in one wave rotating through the Central Plains late Monday night into late Tuesday, and will keep small precipitation chances going with it. Just how strong and moist this system will dictate how much cooling can occur both before and after its passage. && .AVIATION...(For the 18Z TAFs through 18Z Saturday Afternoon) Issued at 1224 PM CDT FRI OCT 18 2013 NAM forecast soundings show only about the lowest 1000 ft above freezing through the afternoon, so there remains the possibility for mixed precip. RAP and HRRR are in reasonable agreement in the precip pushing east of TOP and FOE around 00Z. For the most part, think conditions will be VFR unless some Mixed precip moves in temporarily lowering CIGS and VSBY to MVFR. Once the precip ends, Conditions should be VFR with dry air and subsidence increasing behind the upper wave. && .TOP WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING from 10 PM this evening to 9 AM CDT Saturday FOR KSZ008>012-020>024-026-034>040-054>056-058-059. && $$ SHORT TERM...Wolters LONG TERM...65 AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GOODLAND KS
118 PM MDT FRI OCT 18 2013 .UPDATE... ISSUED AT 114 PM MDT FRI OCT 18 2013 UPDATED FORECAST FOR THE DEVELOPMENT OF RAIN SHOWERS AHEAD OF THE 500MB TROUGH AXIS OUTSIDE OF THE HIGHER SNOWFALL AMOUNTS. THE T-Q INDEX FROM THE RUC PLACES AN AREA OF BETTER INSTABILITY OVER THE NORTHEAST PART OF THE AREA THIS AFTERNOON...SO AM ANTICIPATING THE SHOWERS OVER THE NORTHERN PART OF THE AREA TO INCREASE IN COVERAGE/INTENSITY. THE SHOWERS SHOULD COME TO AN END BY LATE AFTERNOON OR EARLY EVENING WHEN SURFACE HEATING COMES TO AN END. && .SHORT TERM...(TODAY THROUGH SUNDAY NIGHT) ISSUED AT 200 AM MDT FRI OCT 18 2013 TODAY-TONIGHT...AS HAS BEEN ADVERTISED FOR A FEW DAYS AGO UPPER DISTURBANCE WITH A MIX OF RAIN OR SNOW HAS MOVED THROUGH THE NORTHWEST 1/2 OF THE FORECAST AREA EARLY THIS MORNING AND WILL CONTINUE SOUTHEAST THROUGH THE DAY EXITING THE AREA SHORTLY BEFORE SUNSET. PREVIOUS FORECAST HAD A REALLY GOOD HANDLE ON PRECIP TIMING SO ONLY MINOR ADJUSTMENTS NEEDED. BIGGEST CHANGE WAS TO LOWER SNOWFALL AMOUNTS A BIT. SREF SHOWING RATIOS AROUND 5:1 WHICH PRODUCES AMOUNTS AROUND AN INCH EXCEPT IN YUMA...CHEYENNE KS AND CO WHERE AROUND 2 INCHES EXPECTED. LATEST WEB CAM IN YUMA CO SHOWING SNOW JUST NOW STARTING TO STICK TO THE ROADS WITH PERHAPS AN INCH OR SO ON OTHER SURFACES...THIS MATCHES PRETTY WELL WITH THE ONE TO TWO INCHES EXPECTED THROUGH 12Z. WILL LET THE WINTER WEATHER ADVISORY CONTINUE GIVEN ITS THE FIRST SNOW OF THE SEASON AND THE POSSIBILITY THAT PERHAPS A BIT HIGHER AMOUNTS ARE POSSIBLE. HIGHS TODAY UPPER 30S TO MID 40S IN FAR EASTERN COLORADO WITH MID 40S TO LOW 50S ELSEWHERE. LOWS TONIGHT MID 20S TO LOW 30S (WEST TO EAST). FOR SATURDAY THROUGH SUNDAY NIGHT THE FORECAST AREA WILL BE UNDER NORTHWEST FLOW ALOFT. HIGH TEMPERATURES SATURDAY WARM INTO THE UPPER 50S TO MID 60S WITH LOWS GENERALLY IN THE 30S. SOME COOLER AIR MOVES THROUGH THE NORTHWEST 2/3 OF THE AREA SUNDAY AS AN UPPER DISTURBANCE WITHIN THE LARGE UPPER TROUGH MOVES INTO THE AREA. SHOULD SEE AN INCREASE IN CLOUDINESS AND POSSIBLY SOME LIGHT RAIN AND/OR SNOW SUNDAY NIGHT. FOR NOW KEEPING THINGS DRY. HIGHS MID 50S TO AROUND 60 IN EASTERN COLORADO WITH LOW TO MID 60S ELSEWHERE. LOWS SUNDAY NIGHT IN THE 30S. .LONG TERM...(MONDAY THROUGH THURSDAY) ISSUED AT 230 AM MDT FRI OCT 18 2013 MONDAY THROUGH THURSDAY...THE CWA REMAINS UNDER THE INFLUENCE OF THE UPPER TROUGH OVER THE MIDWEST/CENTRAL PLAINS MONDAY THROUGH WEDNESDAY...WITH THE UPPER RIDGE OVER THE ROCKIES MOVING EAST AND BECOMING LESS AMPLIFIED AS IT APPROACHES THE CWA WEDNESDAY NIGHT INTO THURSDAY. THE EXTENDED LOOKS DRY...SINCE MODELS NOW HAVE THE UPPER TROUGH MOVING FURTHER EAST ON WEDNESDAY WITHOUT THE STRONGER VORT LOBE ROTATING THROUGH THE EASTERN PART OF THE CWA EARLY WEDNESDAY MORNING. CLOUD COVER WILL INCREASE ON TUESDAY WITH SOME WEAK VORTICITY MOVING THROUGH THE CWA...WITH PARTLY CLOUDY SKIES RETURNING DUE TO INCREASING SUBSIDENCE ON WEDNESDAY INTO THURSDAY AS THE RIDGE MOVES OVER THE CWA. MONDAY APPEARS TO BE THE COOLEST DAY AFTER THE COLD FROPA LATE SUNDAY/EARLY MONDAY MORNING WITH HIGHS IN THE MID TO UPPER 50S. TEMPERATURES SLOWLY WARM-UP THROUGHOUT THE EXTENDED...WHICH IS A CHANGE FROM YESTERDAY`S MODEL RUNS. SINCE THE MODELS MOVE THE UPPER TROUGH FURTHER EAST BY WEDNESDAY...THE COLD CANADIAN SURFACE HIGH IS FURTHER EAST. THE UPPER RIDGE ALSO BEGINS TO MOVE IN ALONG WITH SMALL HEIGHT RISES...SO HIGHS TUESDAY THROUGH THURSDAY WILL RISE FROM THE LOW 60S TO THE MID TO UPPER 60S. LOW TEMPERATURES WILL REMAIN SLIGHTLY ABOVE NORMAL IN THE UPPER 30S TO LOW 40S....DUE TO CLOUD COVER OVERNIGHT FOR THE FIRST PART OF THE EXTENDED AND DUE TO SLOWLY RISING TEMPERATURES LATER IN THE EXTENDED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1122 AM MDT FRI OCT 18 2013 VFR CONDITIONS FORECAST FOR THE 18Z TAFS. CLOUDS WILL CONTINUE TO MOVE SOUTHEAST TODAY RESULTING IN CLEARING SKIES. UPSTREAM OF KMCK CEILINGS ARE MVFR. AM THINKING THE CEILINGS SHOULD RAISE ABOVE MVFR BEFORE MOVING OVER KMCK. LATE TONIGHT FOG MAY DEVELOP OVER AREAS THAT RECEIVED 2-3 INCHES OR MORE...SO HAVE INCLUDED A SLIGHT REDUCTION IN VISIBILITY FOR KGLD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JTL SHORT TERM...99 LONG TERM...ALW AVIATION...JTL
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1224 PM CDT Fri Oct 18 2013 ...AVIATION UPDATE... .UPDATE... Issued at 954 AM CDT FRI OCT 18 2013 Getting a few reports of big snow flakes mixing in with the rain within the band of higher reflectivity. RAP13 soundings near MHK shows the column above 2 KFT below freezing while the surface temp remains around +3 to +6C. So the bright banding between 500 and 3000 ft is likely from snow melting. Intensity is expected to remain on the light side, although cross sections suggested there is some weak instability and the chance for a brief period of stronger precip. As long as the intensity is light, no accumulation of snow is anticipated. If a band of moderate precip could lead to some light accumulations on grass since surface temps are expected to hold in the lower 40s. && .SHORT TERM...(Today and Tonight) Issued at 420 AM CDT FRI OCT 18 2013 Main focus for the short term is on the advancing shortwave that will bring periods of rain showers across the region today. The mid-level trough that is situated over central Canada and the Dakotas will continue to dig further south into the Central Plains today. Water vapor imagery at 09z showed the main shortwave on the lee side of the Rockies with increasing moisture over northeast Colorado and southwest Nebraska. As the trough deepens today, this shortwave will progress southeastward into western Kansas and round out around the base of the trough over southern Kansas before ejecting into southern Missouri/northern Arkansas tonight as the trough quickly pivots eastward. The regional radar loop showed scattered precipitation developing across northwest Kansas and along the KS/NE border early this morning, tracking eastward toward north central Kansas. This precipitation was being supported by decent mid-level forcing and some isentropic lift. With temperatures in the lower to middle 30s, several locations in northwest Kansas were reporting light snow with this activity early this morning. For this morning, short-range models show some of this scattered early morning activity extending eastward into portions of north central Kansas, however this precipitation is expected to become more widespread across central Kansas by mid/late morning as both the mid-level forcing and isentropic lift in the 300K-310K layer noticeably amplify. This decent forcing and lift will continue to progress into east central and southeast Kansas through the afternoon hours. Still one area of uncertainty is with regards to how well or how quickly this shortwave will be able to overcome the drier air in place over portions of northeast Kansas. Dewpoint depressions this morning are roughly around 5F degrees, and model soundings match up well with the mid-levels quickly saturating this morning with a dry low-layer in place. Several short-range models are trending a bit further north with the northern extent of the precipitation today, compared to the last few runs of many synoptic models. With the early morning precipitation trends across NW Kansas, have trended the pop forecast today toward this more northern solution. While the best potential for precipitation continues to be focused generally along and south of interstate 70 due to the location of the best forcing and lift, have extended low-end chance pops up to the KS/NE border today to account for the potential of more widely scattered showers. As this mid-level trough begins to quickly pivot eastward this afternoon, expect conditions to dry out from northwest to southeast across the CWA during the afternoon hours with a few lingering showers still possible generally along and southeast of the I-35 corridor early this evening. Since this will be a fairly fast-moving system, QPF amounts should generally be less than one-quarter inch. As for temperatures, early morning temperatures as of 09z ranged from the middle 30s to lower 40s. As cloud cover quickly overspreads the area this morning, it will significantly limit the amount of daytime heating that can occur. In fact, expect the high temperatures for the day to be reached by late morning/early afternoon with dropping temperatures through the afternoon hours as precipitation overspreads the region and northwesterly winds usher cooler air into the region. It is worth noting that model soundings show the deep layer of saturation today below 0C degrees. So while precipitation aloft will begin as snow, it is expected to melt and reach the ground as rain as ground temperatures should remain generally in the 3-6C degree range. High temperatures today will struggle to get out of the 40s with readings near 50F degrees possible near the NE/KS border. For tonight, precipitation should be east of the area by midnight with cloud cover quickly diminishing through the overnight hours. These clearing skies combined with already cool temperatures will allow for some decent radiational cooling and low temperatures plummeting into the middle 30s and possibly even into the lower 30s in some of the valleys. These conditions, combined with light westerly winds will provide the potential for some patchy frost across the entire CWA early Saturday morning. .LONG TERM...(Saturday through Thursday) Issued at 420 AM CDT FRI OCT 18 2013 The mid and long term time frame will be dominated by long wave troughing over the Great Lakes region with fast, cold north to northwest flow over the northern half of the Plains. Short wave troughs will frequently move through the flow pattern, and while the bulk of lift and moisture with these systems will be focused northeast of the local forecast area, each trough will bring a cold front through Kansas with reinforcing cold air. One of these fast moving troughs appears that it will focus its energy a bit farther southwest, closer to the local forecast area, on Tuesday. Have added a slight chance of rain on Tuesday for this system, but the remainder of the forecast is dry at this time. Saturday and Sunday may be the warmest days of the coming week with highs in the 60s as a period of warm advection is expected in advance of a late Sunday cold front. Otherwise, expect high temperatures only in the 50s on Monday through Wednesday, and perhaps back into the lower 60s by the end of the week. There may also be several chances for frost, or even freezing temperatures. The primary uncertainty in forecasting a solid freeze on any given night lies in the timing of the fast moving short wave troughs and their impact on night time winds and cloud cover. Tuesday, Wednesday, or Thursday morning all appear to be fine candidates for a frost or freeze, if skies clear and winds become calm, but model guidance is currently out of phase regarding timing of the cold fronts and surface high pressure beyond Monday. && .AVIATION...(For the 18Z TAFs through 18Z Saturday Afternoon) Issued at 1224 PM CDT FRI OCT 18 2013 NAM forecast soundings show only about the lowest 1000 ft above freezing through the afternoon, so there remains the possibility for mixed precip. RAP and HRRR are in reasonable agreement in the precip pushing east of TOP and FOE around 00Z. For the most part, think conditions will be VFR unless some Mixed precip moves in temporarily lowering CIGS and VSBY to MVFR. Once the precip ends, Conditions should be VFR with dry air and subsidence increasing behind the upper wave. && .TOP WATCHES/WARNINGS/ADVISORIES...NONE. && $$ UPDATE...Wolters SHORT TERM...Hennecke LONG TERM...Barjenbruch AVIATION...Wolters
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
1233 PM EDT FRI OCT 18 2013 .SYNOPSIS... HIGH PRESSURE BUILDS BACK ACROSS THE AREA THROUGH SATURDAY BEFORE A COLD FRONT BRINGS SHOWERS AND A SHOT OF COLDER AIR SATURDAY NIGHT. HIGH PRESSURE BUILDS EAST THROUGH MONDAY BEFORE ANOTHER STRONGER FRONT CROSSES THE AREA LATE TUESDAY. UNSETTLED WEATHER WILL CONTINUE THROUGH THE END OF THE WORK WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... .UPDATE... POPS HAVE BEEN DECREASED DRASTICALLY AS LEAST OF THE PRECIPITATION MOVES OUT OF THE AREA. TEMPERATURES HAVE REACHED THE MID 60S WHERE SUBSIDENCE WAS LOCATED THIS MORNING. THIS AREA IS NOW BECOMING INCREASINGLY CLOUDY WITH COLD AIR STRATOCUMULUS AND SOME FAIR WEATHER CUMULUS. MORE CLOUDY LOCATIONS ARE IN THE MID TO UPPER 50S. HAVE ADJUSTED TEMPERATURES SLIGHTLY FOR CURRENT TRENDS. && .PREVIOUS DISCUSSION... LATEST HRRR MODEL RUN CONTINUES TO SHOW THE SHOWER ACTIVITY RAPIDLY EXITING THE FORECAST AREA THIS MORNING. ANY REMAINING PRECIPITATION LIES EAST OF THE ME/NH LINE AS OF 11Z. WILL ADJUST PROBABILITY OF PRECIPITATION ACCORDINGLY. WILL ALSO ALLOW FOR ADJUSTMENTS TO THE WIND FIELDS AS DRAINAGE WINDS CONTINUE NORTH AND EAST OF PORTLAND. FOG CONTINUES ACROSS THE REGION AS WELL...HOWEVER VISIBILITIES WILL SLOWLY IMPROVE WITH TIME EARLY THIS MORNING. WITH COLD AIR ADVECTION AND INCREASING MIXING VALUES...WINDS MAY BE GUSTY AT TIMES. TEMPERATURES WILL STILL MANAGE TO MAKE IT INTO THE 60S IN MOST AREAS. USED A BLEND OF MET/MAV GUIDANCE FOR DAYTIME MAXES THIS AFTERNOON. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/... MAINLY CLEAR SKIES WILL CONTINUE DURING THE OVERNIGHT PERIOD...WITH STILL SOME UPSLOPE CLOUDINESS IN THE WNW FACING HIGHER TERRAIN. THERE WILL BE SOME PATCHY FOG IN THE MORE SHELTERED VALLEYS. A WEAK AND FAST MOVING RIDGE OF HIGH PRESSURE WILL CROSS NORTHERN NEW ENGLAND EARLY SATURDAY MORNING. THIS WILL BE FOLLOWED BY A DISTURBANCE EMBEDDED IN THE INCREASING SW FLOW ALOFT. CLOUDS WILL BE ON THE INCREASE DURING THE DAY AS A WEAK AREA OF LOW PRESSURE FORMS OFF THE MID ATLANTIC COAST. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... HIGH PRESSURE MOVES OFFSHORE SATURDAY AND ALLOWS A WARMER SOUTHWEST FLOW TO DEVELOP ACROSS THE AREA SATURDAY IN ADVANCE OF THE NEXT FRONTAL SYSTEM WHICH WILL MOVE THROUGH THE REGION SATURDAY NIGHT. SCATTERED SHOWERS WILL SPREAD ACROSS THE REGION LATE SATURDAY AND SAT NIGHT IN ADVANCE OF THE COLD FRONT. HIGH PRESSURE QUICKLY BUILDS IN FOR SUNDAY AND MONDAY. TEMPERATURES STAY NEAR SEASONAL NORMALS WITH A FAIR AMOUNT OF SUNSHINE. THE NEXT FRONT IS EXPECTED TO MOVE ACROSS THE REGION LATE TUESDAY INTO TUESDAY NIGHT. SHOWERS ONCE AGAIN CAN BE EXPECTED ALONG AND AHEAD OF THE FRONT. BEHIND THE FRONT A MUCH COLDER AIR MASS WILL FILTER ACROSS THE AREA WITH SNOW SHOWERS IN THE MOUNTAINS EXPECTED ON WEDNESDAY. BY WED NIGHT OR THU NIGHT FROST OR FREEZING CONDITIONS ARE EXPECTED TO REACH THE COASTAL AREAS. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... SHORT TERM...CEILINGS AND VISIBILITIES WILL REMAIN LOW THROUGH DAYBREAK AS A COLD FRONT PUSHES THROUGH. MANY SITES WILL SEE IFR/LIFR CONDITIONS BETWEEN 08Z AND 14Z. CONDITIONS WILL RAPIDLY IMPROVE THEREAFTER. LONG TERM... VFR SATURDAY. COULD SEE MVFR/IFR IN SHOWERS SATURDAY NIGHT. SHOULD BE VFR AGAIN SUNDAY THROUGH EARLY TUESDAY. && .MARINE... SHORT TERM...SCA CONTINUES AND HAS BEEN EXTENDED THROUGH TONIGHT...AS A COLD FRONTAL PASSAGE INCREASES WIND GUSTS AND WAVE HEIGHTS. LONG TERM... WINDS/SEAS TO REMAIN BLO SCA CONDS THROUGH MONDAY. WINDS/SEAS WILL INCREASE AND REACH SCA CONDS TUES DUE TO AN INCRG SLY GRADIENT AHEAD OF AN APPROACHING CDFNT. THE COLD FRONT MOVES ACROSS THE WATERS TUES NIGHT WITH GSTY WLY WINDS BEHIND THE FROPA THAT WILL CONTINUE THROUGH WED. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR ANZ150-152- 154. && $$ UPDATE...HANES
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
155 PM EDT FRI OCT 18 2013 .UPDATE... ISSUED AT 1014 AM EDT FRI OCT 18 2013 SFC LOW CURRENTLY OVER EASTERN LK SUPERIOR BETWEEN CARIBOU ISLAND AND WHITEFISH POINT. TROUGH EXTENDING WEST FROM THE LOW WITH NNW WINDS ALREADY NEAR THE SHORE AT MQT AND PUSHING TOWARD MUNISING. COOLING IN WAKE OF TROUGH IS SPILLING ACROSS LK SUPERIOR LEADING TO INCREASING OVERWATER INSTABILITY. BASED ON H85 TEMPS FM RUC THE DELTA T/S RIGHT NOW OVER LK SUPERIOR ARE 12-14C. SHOWERS STREAMING IN OFF LK SUPERIOR BTWN MARQUETTE AND MUNISING ARE LIKELY A RESULT OF INSTABILITY AND LOW-LEVEL CONVERGENCE. ELSEWHERE...WIDESPREAD RAIN IS OCCURRING OVER MUCH OF THE NORTHERN CWA. RAIN AMOUNTS LIGHT WITH AVAILABLE AUTOMATED STATIONS SHOWING ONLY A HUNDREDTH OR TWO IN AN HOUR. AS SHORTWAVE TO THE WEST SLIDES ACROSS THROUGH EARLY THIS AFTN AND INTERACTS WITH NNW CYCLONIC FLOW AND THE INCREASING INSTABILITY...EXPECT SHOWERS OVER THE WEST TO INCREASE OVER THE HIGHER TERRAIN. RUC13 MAY BE OVERDONE WITH ITS QPF AMOUNTS...BUT IS PROBABLY ON THE RIGHT TRACK WITH AT LEAST THE AREAL DEPICTION. MAIN ADJUSTMENT WAS TO INCREASE POPS ALL AREAS THROUGH THE MORNING FOR THE WIDESPREAD LIGHT RAIN...THEN KEEP HIGHER POPS LONGER OVER THE WEST THIS AFTN DUE TO THE LK EFFECT. PRECIP WILL TREND DOWN THIS EVENING AS SFC TROUGH MOVES EAST OF THE AREA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 507 AM EDT FRI OCT 18 2013 RAIN SHOWERS OVER THE WRN CWA AND PARTS OF MN AND WI ARE BEING DRIVEN BY A COLD FRONT ALONG THE LEADING EDGE OF THE SHOWERS...SUCH AS WHERE HIGHER RADAR REFLECTIVITIES AND GRADIENTS ARE OVER SCENTRAL LAKE SUPERIOR/NCENTRAL UPPER MI AT THE CURRENT TIME /0730Z/. BEHIND THE INITIAL COLD FRONTAL PRECIP...THE WIDESPREAD RAIN IS BEING DRIVEN BY A SHORTWAVE NEAR MPX AND UPPER LEVEL HEIGHT FALLS FROM A STRONG UPPER TROUGH PUSHING INTO THE REGION FROM THE N. EVEN WITH SUB FREEZING 850MB TEMPS BEHIND THE COLD FRONT...THERE IS NO SNOW BEING REPORTED AS LOW LEVEL TEMPS BELOW 850MB ARE TOO WARM FOR FROZEN PRECIP TO MAKE IT TO THE GROUND. EXPECT BEST COVERAGE OF RAIN TO BE OVER WRN UPPER MI THROUGH MOST OF THE MORNING AS THE COLD FRONT OUTRUNS BEST UPPER LEVEL SUPPORT /KEEPING RAIN COVERAGE LOWER AS THE FRONT MOVES E/ AND THE SHORTWAVE MOVES OVER WRN UPPER MI AROUND 18Z. BEHIND THE SHORTWAVE AND AHEAD OF THE UPPER TROUGH AXIS...A BRIEF RIDGE PASSES THROUGH TONIGHT...WHICH SHOULD PROVIDE A LULL IN PRECIP. HOWEVER...AFTER THE RIDGE PASSES...CONDITIONS BECOME MORE FAVORABLE FOR LAKE EFFECT/ENHANCED PRECIP AS 850MB TEMPS WILL BE AROUND -3C OVER THE RELATIVELY WARM 8-10C WATERS OF LAKE SUPERIOR WITH NW LOW LEVEL WINDS. THINK THE INCREASE IN SHOWER COVERAGE WILL BE LATE TONIGHT AFTER 03Z. WITH THE COLDER 850MB TEMPS...SOME SNOW COULD MIX IN WITH THE RAIN LAT TONIGHT WHEN NEAR SFC TEMPS ARE COOLER. STILL NOT EXPECTING ANY SNOWFALL ACCUMULATIONS IN THE SHORT TERM.. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 507 AM EDT FRI OCT 18 2013 SATURDAY AND SATURDAY NIGHT...THE MODELS WERE IN REASONABLE AGREEMENT IN DROPPING A SHORTWAVE INTO THE REGION WITH THE STRONGEST 850-500 MB QVECTOR CONV TO THE SOUTH OF UPPER MI. HOWEVER...THE FORCING AHEAD OF THE SHRTWV ALONG WITH RELATIVELY STEEP 900-600 MB LAPSE RATES WILL BE STRONG ENOUGH TO SUPPORT SCT/NMRS SHOWERS SPREADING FROM WEST TO EAST THROUGH THE CWA. FCST SOUNDINGS SUGGEST THAT A RAIN/SNOW MIX WILL BE POSSIBLE IN THE MORNING BEFORE DIURNAL WARMING AND WEAK WAA CHANGES THE PCPN OVER TO RAIN. WITH MAINLY W OR WNW WINDS BY SAT NIGHT AND 850 MB TEMPS DOWN TO AROUND -4C...THE BEST CHANCE FOR ENHANCED SHOWERS ARE EXPECTED MAINLY OVER THE KEWEENAW AND LOCATIONS EAST OF MUNISING. SUN INTO MON...THE GFS AND ECMWF REMAINED IN GOOD AGREEMENT WITH A STRONGER SHRTWV DROPPING TO THE SOUTH FROM NRN MANITOBA. AS THE ASSOCIATED SFC LOW MOVES FROM WI TO ERN UPPER MI...AN AREA OF 285K-295 ISENTROPIC LIFT WILL SUPPORT AN AREA OF PCPN MOVING INTO SW UPPER MI SUN AFTERNOON AND ACROSS THE CWA SUN NIGHT. FCST SOUNDINGS...AND WET-BULB ZERO HEIGHTS SUPPORT POTENTIAL FOR ACCUMULATING SNOW OVER THE HIGHER TERRAIN OF THE WEST HALF OF UPPER MI. WITH ONLY LIGHT TO MODERATE SNOWFALL RATES EXPECTED...AND RELATIVELY LOW SNOW/WATER RATIO VALUES AOB 10/1...ANY ACCUMULATIONS SHOULD REMAIN MAINLY BELOW AN INCH. MODELS SHOWED GREATER DIFFERENCES BY LATER MONDAY AS THE GFS WAS MORE AGGRESSIVE IN DIGGING THE SHRTWV TO THE SOUTH ALLOWING LOW LEVEL WINDS TO VEER MORE NRLY COMPARED TO THE ECMWF. EITHER SOLUTION SUGGESTS THAT WITH DEEP MOISTURE AND CYCLONIC FLOW AND 850 MB TEMPS TO AROUND -6C...LAKE ENHANCED PCPN WILL AFFECT THE NORTH HALF OF UPPER MI THROUGH MON NIGHT. THERE SHOULD ALSO BE ENOUGH LOW LEVEL COLD AIR FOR SOME ACCUMULATING SNOW...ESPECIALLY WHERE UPSLOPE NW TO NNW FLOW PREVAILS. CONFIDENCE IN PCPN/SNOW AMOUNTS IS LOW GIVEN MODEL DIFFERENCES WITH THE DETAILS OF LOW LEVEL WINDS. TUE-THU...WITH THE MEAN LONG WAVE TROUGH POSITION REMAINING OVER THE GREAT LAKES AND ERN CONUS...NW FLOW AND WEAK CLIPPER SHRTWVS ARE EXPECTED TO MOVE THROUGH THE WRN LAKES. THIS WILL BRING PERIODS OF LIGHT PCPN THAT WILL BE ENHANCED BY LAKE SUPERIOR AS 850 MB TEMPS REMAIN IN THE -6C TO -9C RANGE. LOCATIONS FAVORED BY WNW TO NW FLOW ARE LIKELY TO SEE THE GREATEST PCPN CHANCES. SOME ADDITIONAL ACCUMULATING SNOW MAY BE POSSIBLE ALTHOUGH THE AS IS TYPICAL IN EARLY SEASON LAKE EFFECT REGIMES...GRAUPEL WILL LIKELY ALSO BE MIXED WITH ANY RAIN/SNOW SHOWERS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 152 PM EDT FRI OCT 18 2013 SHOWERS WITH VFR VSBY AND MVFR CIGS DIMINISH LATER TODAY AS LOW PRESSURE MOVES TO THE EAST OF LK SUPERIOR. LOW CIGS MAY LINGER THROUGH MUCH OF THE NIGHT BUT SHOULD SCATTER OUT LATER TONIGHT AT CMX AND SAW. CLOUDS THICKEN ON SATURDAY WITH THE APPROACH OF ANOTHER LOW PRESSURE SYSTEM. CONDITIONS WILL MAINLY STAY VFR UNTIL LATER SATURDAY. SOME SHOWERS MAY START TO IMPACT IWD BY LATE SATURDAY MORNING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 507 AM EDT FRI OCT 18 2013 A TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT MOVING ACROSS EASTERN LAKE SUPERIOR TODAY WILL SHIFT EASTWARD TODAY...WITH A BRIEF RIDGE BUILDING BACK IN TONIGHT. WINDS JUST BEHIND THE FRONT MAY BRIEFLY GUST TO 20 TO 30KTS FRIDAY INTO FRIDAY EVENING. DURING THE DAY SATURDAY THROUGH MUCH OF SUNDAY ANOTHER AREA OF LOW PRESSURE WILL APPROACH LAKE SUPERIOR...CAUSING THE PRESSURE GRADIENT TO INCREASE ONCE AGAIN. THIS MAY CAUSE WINDS TO INCREASE TO 20 TO 30 KNOTS...ESPECIALLY SATURDAY NIGHT INTO SUNDAY. MONDAY NIGHT THROUGH TUESDAY...ANOTHER...MORE INTENSE AREA OF LOW PRESSURE...IS SET TO SHIFT INTO THE REGION ALLOWING WINDS TO INCREASE OVER THE LAKE ONCE AGAIN. DURING THIS TIME FRAME WINDS MAY GUST TO NEAR GALES OF 35 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ UPDATE...JLA SHORT TERM...TITUS LONG TERM...JLB AVIATION...JLA MARINE...TITUS
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1257 PM CDT Fri Oct 18 2013 .UPDATE: Issued at 1239 PM CDT Fri Oct 18 2013 Coverage of rain has continued to expand this morning across ern KS with a finger extending into nw and n cntrl MO. This finger exist due to strong frontogenetical forcing. This forcing is expected to work east across ne MO and w cntrl IL this aftn and continue into the evening before weakening. This will cause this band to continue to work slowly east this aftn and then dsspt this evening. By 3Z, the forcing shifts south along the I70 corridor which will cause the rest of the precip shield to overspread the rest of the CWA overnight. This caused a fairly significant change in the fcst. POPs were shifted north and increased for this aftn. The other fcst elements seemed to be in decent shape. 2% && .SHORT TERM: (Through Late This Afternoon) Issued at 320 AM CDT Fri Oct 18 2013 A weak cold front was moving through the region early this morning, but its only effect across the LSX CWA will be a wind shift from southwest to northwest after fropa. Early morning water vapor imagery along with recent RAP analyses of the 1.5 PVU surface both depict a positively tilted trough over the central CONUS with a couple of stout disturbances sliding down the western side of the trough. Increasing large scale ascent ahead of these vorticity centers will support scattered rain showers from this afternoon into tonight. Since it may take some time to saturate the initially dry air mass, precipitation chances look higher after 19/00z compared to earlier in the afternoon. Kanofsky .LONG TERM: (Tonight through Thursday) Issued at 320 AM CDT Fri Oct 18 2013 Precipitation threat overnight is expected to transition from very light showers during the early evening attempting to stream east- northeast from mid MO, to a broader area of rain developing over the southeast half of the CWA during the overnight hours as upstream shortwave begins to push into mid Mississippi Valley and the large scale ascent is realized over the CWA. Believe the NAM is too far southeast with its QPF in the 06-12z time frame, as almost all over solutions have northern fringes of QPF north of STL. While specifics may be a bit off, the 3 hourly PoP trends from the 03z SREF look very reasonable. This rain should wind down late tonight or very early Saturday morning over our southeast counties as shortwave exits to the east. The brief cool-down in the wake of this feature will quickly give way to WAA in advance of the next shortwave from late Saturday afternoon, with fairly strong warming forecast over most of the CWA from late Saturday night into Sunday. By Sunday afternoon all short range models are forecasting at least 8C 850mb temps over the CWA, with thermal ridge extending from southeast Kansas into ne MO possibly pushing temps to around 10C. Given this trend have upped temps about a category from going forecasts, and most areas should push the 70 degree mark. Heading into the medium range, upper level trof is forecast to deepen over the eastern CONUS in the wake of the aforementioned shortwave, and this will bring even colder air into the region for the start of the new week. The airmass that pushes into the area Monday night and Tuesday will be the coldest so far of this fall, and its certainly possible that the growing season could come to an end in some areas either Tuesday or Wednesday morning. However, the frost threat will depend on timing of surface ridge and any clouds that advect into the region on the fairly dirty northwest flow, and specifics with both the high and clouds are not clear at this time. Based on progged 850mb temps it appears that during the Tuesday-Thursday time frame highs will only be in the 50s with lows in the 30s. At this time have kept PoPs in the slight chance range with the passage of the cold front Sunday night and Monday due to very limited moisture. Have also continued slight chance PoPs over the area on Tuesday night as another weak shortwave drops into the area. Truett && .AVIATION: (For the 18z TAFs through 18z Saturday Afternoon) Issued at 1239 PM CDT Fri Oct 18 2013 A strong upper level disturbance will affect the terminals this period. Clouds and eventually rain will overspread the area NW to SE from late this aftn near KUIN to the STL metro area shortly before midnight. The rain should last 3-6 hrs with skies clearing fairly quickly after the rain ends. There is the potential for IFR CIGS with the precip but am not confident on timing and coverage to include attm. With recent rainfall and clearing skies prior to sunrise, think there may be a limited fog potential. The potential is limited due to winds in the 5-10 kt range and drier air moving into the area behind the rain. KCOU and KUIN have the best chance of seeing fog due to the time skies are expected to be clear prior to sunrise. Uncertainties preclude mentioning attm. Specifics for KSTL: MVFR CIGS fcst/VFR VSBY fcst. Clouds will increase this aftn and evening with rain beginning before midnight and lasting several hours. Skies should clear around sunrise. 2% && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1232 PM CDT Fri Oct 18 2013 .SHORT TERM...(Today through Sunday Night) Issued at 405 AM CDT FRI OCT 18 2013 Long wave troughing persisted across the central CONUS early this morning, and this pattern appears locked in for the next couple of weeks. Embedded within the the large scale dip, the third in a recent sequence of shortwave impulses was tracking southward through Wyoming, and remains on track to target the southern half of the CWA later today. Front Range, CO radar shows an impressive band of snow expanding over NE Colorado, while satellite imagery shows mid cloud rapidly expanding eastward across srn Nebraska and most of Kansas. These trends suggest that the axis of strong elevated frontogenesis will likely come in a bit further north than earlier progged. This is supported by a northward shift in the 00Z model solutions and more recently the hourly RAP output. For today, cloud cover will quickly overspread the CWA from west to east this morning. Forecast soundings and model cross sections show a rapid top- down saturation as sloped 700-500mb frontogenesis increases in response to large scale height falls isentropic ascent. Despite clear skies presently, precipitation could begin over ern KS/west central MO as early noon. As discussed yesterday, the sub- cloud layer will initially be very dry while 850-700mb temperatures fall sharply as the shortwave approaches. In fact, if not for the boundary layer, we would likely be dealing with wet snow! Nonetheless, once the rain begins, surface temps will immediately respond to diabatic cooling and fall back through the 40s. Hourly temperatures reflect a non-diurnal curve for the afternoon. Precipitation should reach a local maximum between 18-00Z, steadily shifting southward with time as a small 700-500mb jet streak develops and shifts the axis of greatest mid level forcing. QPF amounts will average between one and two tenths of an inch, generally along and south of I-70. The mid level trough axis will quickly pivot across the CWA overnight, with skies gradually clearing from west to east. Temps will fall into the mid 30s by daybreak, and although conditions are not optimal for a widespread frost, the moist boundary layer and diminishing winds could enhance the potential. Next shift may want to consider headlines for all or portions of the region tonight. After a chilly day Saturday, strengthening west winds will develop south of a progressive shortwave trough moving across the Upper Midwest. Strong low level warm advection will begin Saturday night and continue into Sunday, with a deep layer Chinook component expected to rapidly spread some mild air eastward across the Plains. Given upward trends in 850mb temp progs, have bumped highs into the upper 60s to around 70 for Sunday, and made a significant increase to the surface winds/gusts over the srn half of the CWA. A dry cold front will sweep across the area Sunday night, leading to a very challenging low temperature forecast that hinges entirely on where the front ends up by 8AM. Current forecast projects a near 15 degree gradient from mid 30s along the Iowa border to near 50 across mid Missouri, and significant adjustments remain possible. .LONG TERM...(Monday through Thursday) Issued at 403 AM CDT FRI OCT 18 2013 Later half of the forecast will continue the cool trend as negative height anomalies persist across the Lower Missouri River Valley through much of next week. As Monday arrives a significant trough will be digging in across the center of the nation providing cold air from the Canadian Plains with plenty of opportunity to rush south through the northern and central Plains. Resulting cold air with the northwest flow will keep temperatures ranging below normal through the week. This is supported by 850mb model output which advertises subzero centigrade temperatures sweeping into the region Monday, and again Wednesday behind a small shortwave trough zipping through the flow. This should make for some cool fall conditions next week with highs only the 50s expected Monday through Wednesday. As for overnight low, a bit of a frost might be in the offing. Overnight lows will drop into the 30s Tuesday, Wednesday and Thursday mornings. Currently, areas along and north of highway 36 look to have the greatest chance for seeing repeated frost. Otherwise, have included a silent slight chance for showers Wednesday into Thursday. Models continue to advertise a shortwave trough zipping through the northwest flow mid-week, providing a little reinforcing shot of cold air for Thursday mornings lows. Models might be over doing the amount of moisture, thus confusing low cloud cover with QPF, though disturbances in the northwest flow often squeeze some light precipitation out across eastern Kansas or Missouri. Have left the silent slight chance POPs characterized as showers for now, though if confidence in Tuesdays quick shortwave improves some consideration might be needed for including snow in the precipitation forecast. && .AVIATION...(For the 18Z TAFS through 18Z Saturday Afternoon) Issued at 1232 PM CDT FRI OCT 18 2013 Areas of light to moderate rain will spread northeast early this afternoon, before beginning to push southeastward during the late afternoon and evening hours. Although ceilings are expected to stay VFR, visibilities could briefly drop below 5 miles in the heavier rain. Precipitation should end from northwest to southeast between 00z and 03z, leaving behind VFR conditions and light winds tonight. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ SHORT TERM...Bookbinder LONG TERM...Cutter AVIATION...Laflin
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1250 PM CDT FRI OCT 18 2013 .SYNOPSIS... ISSUED AT 333 AM CDT FRI OCT 18 2013 H5 ANALYSIS FROM EARLIER THIS EVENING CONTINUES TO INDICATE A LONGWAVE TROUGH OF LOW PRESSURE LOCATED ACROSS THE CONUS WITH RIDGING OFF THE PACIFIC COAST OF THE US AND CANADA. RIDGING EXTENDED FROM THE WESTERN ATLANTIC INTO GREENLAND. EMBEDDED SHORTWAVES WERE NOTED ACROSS THE NORTHERN CONUS ATTM...WITH ONE LOCATED OVER THE EASTERN DAKOTAS...AND A SECOND ACROSS THE NORTHERN ROCKIES. THE SECOND FEATURE CONTINUES TO TRACK TO THE SOUTH SOUTHEAST INTO WYOMING...COLORADO AND WESTERN PORTIONS OF KANSAS THIS MORNING PER WV IMAGERY. ENHANCED FRONTOGENESIS ALONG AN AXIS EXTENDING FROM CHEYENNE WYOMING INTO NWRN KS...HAS LED TO RAIN AND SNOW SHOWERS ACROSS NERN COLORADO...SERN WYOMING...NWRN KS...SWRN NEBRASKA AND THE SOUTHERN NEBRASKA PANHANDLE. ACROSS SOUTHWESTERN NEBRASKA...SOME LIGHT SNOW WAS BEING REPORTED AT IMPERIAL OVER THE PAST COUPLE OF HOURS...WITH ONLY A FEW HUNDREDTHS OF AN INCH OF PRECIPITATION REPORTED. ELSEWHERE...COLD TEMPERATURES WERE PRESENT ACROSS CENTRAL AND NORTH CENTRAL NEBRASKA WITH 2 AM CDT READINGS RANGING FROM 25 AT BROKEN BOW...TO 32 AT NORTH PLATTE AND ONEILL. VERY DRY AIR WAS IN PLACE ACROSS NORTH CENTRAL NEBRASKA TONIGHT WITH DEW POINTS IN THE MID 20S. THIS DRY AIR EXTENDED WELL NORTH OF THE AREA INTO SOUTH DAKOTA. && .UPDATE... ISSUED AT 1134 AM CDT FRI OCT 18 2013 UPDATE TO THE FORECAST TO ACCOUNT FOR THE CLEARING SKIES ACROSS THE HEART OF THE SANDHILLS AND THE POTENTIAL OF LIGHT SHOWERS OF RAIN ACROSS OUR FAR SOUTHWEST. UPSTREAM OBSERVATIONS/HIGHWAY CAMERAS AT KSNY AND KIMB HAVE SHOWN -SN AT BOTH LOCATIONS AS INCREASING CLOUDS INVADE FROM THE WEST WITH AN APPROACHING MID LEVEL WAVE. THE HRRR WOULD SUGGEST THE PRECIPITATION THREAT ENDING ACROSS THE SOUTHWEST AROUND 20Z...WILL GO WITH THIS IDEA. THE HRRR ALSO INDICATES THE POTENTIAL OF ADDITIONAL -SHRA OR SPRINKLES LATER THIS AFTERNOON FOR MUCH OF THE SANDHILLS REGION...IN AN ATMOSPHERE CHARACTERIZED AS DRY BUT WITH STEEP LOWER LEVEL LAPSE RATES. PREVIOUS FORECAST HAS THIS SITUATION HANDLED WELL WITH A BROAD ISOLATED MENTION...THUS NO OTHER CHANGES NEEDED AT THIS TIME. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 333 AM CDT FRI OCT 18 2013 THIS MORNING...PRECIPITATION WILL CONTINUE TO SHIFT TO THE SOUTH AND EAST INTO EAST CENTRAL COLORADO AND NORTHERN KANSAS THROUGH MIDDAY. AS OF FCST ISSUANCE TIME...THE NRN PERIPHERY OF PRECIPITATION IS EXPECTED TO BE SOUTH OF THE NEBR PANHANDLE...AND CONFINED TO PERKINS...CHASE...HAYES...WESTERN FRONTIER AND SWRN LINCOLN COUNTIES. THIS AREA OF PCPN IS EXPECTED TO CLEAR THE SWRN FCST AREA BY MID MORNING. FOR THE REST OF TODAY...A SECONDARY SHORTWAVE WILL TRACK ACROSS THE DAKOTAS AND NEBRASKA THIS AFTERNOON. INHERITED FORECAST HAD SLIGHT CHANCE POPS LATER THIS MORNING AND THIS AFTERNOON ACROSS A LARGE CHUNK OF CENTRAL AND NORTH CENTRAL NEBRASKA. DECIDED TO SCALE THIS BACK SOMEWHAT TO MAINLY SPRINKLES...AND ISOLATED SHOWERS DURING THE MID TO LATE AFTERNOON HOURS. FCST SOUNDINGS ACROSS THE CENTRAL AND NRN CWA...CONTINUE TO INDICATE VERY DRY CONDS IN THE SURFACE TO 5000-7000 FT AGL LAYER...WITH LAYER PW`S A MERE .3 INCHES...SO FEEL SPRINKLES ARE WARRANTED HERE. ACROSS FAR NORTHEASTERN AREAS...WILL CONTINUE ISOLATED SHOWERS DURING THE MID TO LATE AFTERNOON HOURS...AS STEEP LAPSE RATES REMAIN IN PLACE...AND MOISTURE IS A LITTLE BETTER ACROSS THE NORTHEASTERN CWA. HIGHS THIS AFTERNOON WILL RANGE FROM THE UPPER 40S IN THE NORTHWEST...TO THE LOWER 50S ELSEWHERE. FOR TONIGHT...THE UPPER LEVEL SHORTWAVE...WILL SLIDE EAST OF THE FORECAST AREA LEADING TO CLEARING SKIES IN THE CENTRAL AND WEST...AS WELL AS COLD TEMPERATURES. WITH DRY AIR IN PLACE AND FAIRLY LIGHT WESTERLY WINDS...LOWS WILL BOTTOM OUT MID TO UPPER 20S IN THE WEST...AROUND 30 IN THE CENTRAL AND LOWER 30S IN THE NORTHEAST WHERE CLOUD COVER WILL BE MORE PREVALENT. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 333 AM CDT FRI OCT 18 2013 SATURDAY AND SUNDAY THE EASTERN PAC RIDGE WILL SLOWLY SHIFT ONSHORE AND BEGIN TO AMPLIFY...NOSING INTO WESTERN CANADA. FLOW BECOMES NORTHWESTERLY THEN MORE NORTHERLY. A LONG WAVE TROUGH WILL SET UP ACROSS THE GREAT LAKES REGION. THIS WILL BRING AN ACTIVE PATTERN WITH SEVERAL DISTURBANCE TO MOVE ACROSS THE NORTHERN PLAINS. TWO MAJOR CONCERNS WITH THE FORECAST FOR THE WEEKEND INTO NEXT WEEK. AVAILABILITY OF MOISTURE IS ONE. 00Z KLBF SOUNDING LAST NIGHT ONLY HAD 0.37 INCHES OF PWATS...AND NW FLOW WILL CONTINUE TO LIMIT MOISTURE RETURN. EACH PASSING DISTURBANCE WILL SEE STEEP LAPSE RATES AND POCKETS OF GOOD FRONTOGENESIS...HOWEVER LACK OF MOISTURE IS EXPECTED TO RESULT IN ONLY PASSING CLOUDS AND ISOLATE LIGHT RAIN/SNOW SHOWERS. GENERALLY LIQUID DURING THE DAYTIME...WHILE OVERNIGHT MAY SEE A MIX OF RAIN AND SNOW AS TEMPS DROP INTO THE LOWER TO MID 30S. TIMING OF WAVES IS SUNDAY AND ANOTHER SUNDAY NIGHT INTO MONDAY...FOLLOWED BY ONE MORE ON TUESDAY. THE RIDGE BY MID WEEK WILL BEGIN TO PUSH THE WAVES FURTHER EAST AND SHOULD SEE DRY CONDITIONS PREVAIL FOR REST OF THE WEEK. THE SECOND CONCERN FOCUSES ON TEMPERATURES. COLD AIR WILL DEFINITELY BE DRAW OVER THE GREAT LAKES...WHILE WARM AIR BUILDS ACROSS THE SW CONUS. THE HIGH PLAINS WILL BE IN THE BATTLE GROUND WITH TEMPS HIGHLY DEPENDENT ON CLOUD COVER AND THE WESTWARD PUSH OF THE COLD AIR. THE MODELS ARE STRUGGLING WITH THE COLD AIR AT THE SFC NEXT WEEK...EVIDENT BY THE LATEST MEX GUIDANCE. TUESDAY MOS GUIDANCE TEMPS JUMPED FROM UPPER 40S TO LOWER 50S...TO THE LOWER AND MID 60S. OVER THE WEEKEND NOT EXPECTING TO MUCH VARIATION FROM MOS GUIDANCE AS POCKETS OF CLOUDS TO KEEP HIGHS AT OR BELOW SEASONAL NORMALS...MID TO UPPER 50S. BY MID WEEK...AS THE UPPER LEVEL RIDGE INCREASES HEIGHTS...TEMPS SHOULD GO UP. WOULD BE MORE CONCERNED ABOUT THE COLD AIR REMAINING IN PLACE IF THERE WAS A SNOW PACK...HOWEVER WITH NOT SNOW WILL FAVOR A UPWARD TREND IN THE FORECAST...TRENDING TOWARDS THE NEW GFS SOLUTION. STILL WOULD LIKE TO SEE MORE CONSISTENCY WITH THE MODELS AS CONFIDENCE IS LOW FOR THE MID NEXT WEEK FORECAST. TUESDAY AND WEDNESDAY MODEL 850 MB TEMPS HAVE A RANGE OF MORE THAN 10 DEGREES C AMONGST THE MANY MEMBERS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1250 PM CDT FRI OCT 18 2013 AN UPPER LEVEL TROUGH OF LOW PRESSURE CONTINUES TO TRACK ACROSS THE DAKOTAS TODAY...BRINGING INCREASING CLOUDINESS BACK ACROSS THE SANDHILLS REGION OF NEBRASKA. THERE IS A SIGNAL FOR ISOLATED SHOWERS THIS AFTERNOON...HOWEVER SHORT GUIDANCE IS SPLIT AS ENOUGH DRY AIR IS IN PLACE TO LIMIT COVERAGE. THUS WILL MAINTAIN A DRY FORECAST AT BOTH THE KLBF AND KVTN TERMINALS...AND UPDATE IF NEEDED. WINDS TODAY WILL BE GUSTY AND OUT OF THE NORTHWEST...BUT SHOULD WEAKEN OVERNIGHT. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JACOBS SYNOPSIS...CLB SHORT TERM...CLB LONG TERM...MASEK AVIATION...JACOBS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1134 AM CDT FRI OCT 18 2013 .SYNOPSIS... ISSUED AT 333 AM CDT FRI OCT 18 2013 H5 ANALYSIS FROM EARLIER THIS EVENING CONTINUES TO INDICATE A LONGWAVE TROUGH OF LOW PRESSURE LOCATED ACROSS THE CONUS WITH RIDGING OFF THE PACIFIC COAST OF THE US AND CANADA. RIDGING EXTENDED FROM THE WESTERN ATLANTIC INTO GREENLAND. EMBEDDED SHORTWAVES WERE NOTED ACROSS THE NORTHERN CONUS ATTM...WITH ONE LOCATED OVER THE EASTERN DAKOTAS...AND A SECOND ACROSS THE NORTHERN ROCKIES. THE SECOND FEATURE CONTINUES TO TRACK TO THE SOUTH SOUTHEAST INTO WYOMING...COLORADO AND WESTERN PORTIONS OF KANSAS THIS MORNING PER WV IMAGERY. ENHANCED FRONTOGENESIS ALONG AN AXIS EXTENDING FROM CHEYENNE WYOMING INTO NWRN KS...HAS LED TO RAIN AND SNOW SHOWERS ACROSS NERN COLORADO...SERN WYOMING...NWRN KS...SWRN NEBRASKA AND THE SOUTHERN NEBRASKA PANHANDLE. ACROSS SOUTHWESTERN NEBRASKA...SOME LIGHT SNOW WAS BEING REPORTED AT IMPERIAL OVER THE PAST COUPLE OF HOURS...WITH ONLY A FEW HUNDREDTHS OF AN INCH OF PRECIPITATION REPORTED. ELSEWHERE...COLD TEMPERATURES WERE PRESENT ACROSS CENTRAL AND NORTH CENTRAL NEBRASKA WITH 2 AM CDT READINGS RANGING FROM 25 AT BROKEN BOW...TO 32 AT NORTH PLATTE AND ONEILL. VERY DRY AIR WAS IN PLACE ACROSS NORTH CENTRAL NEBRASKA TONIGHT WITH DEW POINTS IN THE MID 20S. THIS DRY AIR EXTENDED WELL NORTH OF THE AREA INTO SOUTH DAKOTA. && .UPDATE... ISSUED AT 1134 AM CDT FRI OCT 18 2013 UPDATE TO THE FORECAST TO ACCOUNT FOR THE CLEARING SKIES ACROSS THE HEART OF THE SANDHILLS AND THE POTENTIAL OF LIGHT SHOWERS OF RAIN ACROSS OUR FAR SOUTHWEST. UPSTREAM OBSERVATIONS/HIGHWAY CAMERAS AT KSNY AND KIMB HAVE SHOWN -SN AT BOTH LOCATIONS AS INCREASING CLOUDS INVADE FROM THE WEST WITH AN APPROACHING MID LEVEL WAVE. THE HRRR WOULD SUGGEST THE PRECIPITATION THREAT ENDING ACROSS THE SOUTHWEST AROUND 20Z...WILL GO WITH THIS IDEA. THE HRRR ALSO INDICATES THE POTENTIAL OF ADDITIONAL -SHRA OR SPRINKLES LATER THIS AFTERNOON FOR MUCH OF THE SANDHILLS REGION...IN AN ATMOSPHERE CHARACTERIZED AS DRY BUT WITH STEEP LOWER LEVEL LAPSE RATES. PREVIOUS FORECAST HAS THIS SITUATION HANDLED WELL WITH A BROAD ISOLATED MENTION...THUS NO OTHER CHANGES NEEDED AT THIS TIME. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 333 AM CDT FRI OCT 18 2013 THIS MORNING...PRECIPITATION WILL CONTINUE TO SHIFT TO THE SOUTH AND EAST INTO EAST CENTRAL COLORADO AND NORTHERN KANSAS THROUGH MIDDAY. AS OF FCST ISSUANCE TIME...THE NRN PERIPHERY OF PRECIPITATION IS EXPECTED TO BE SOUTH OF THE NEBR PANHANDLE...AND CONFINED TO PERKINS...CHASE...HAYES...WESTERN FRONTIER AND SWRN LINCOLN COUNTIES. THIS AREA OF PCPN IS EXPECTED TO CLEAR THE SWRN FCST AREA BY MID MORNING. FOR THE REST OF TODAY...A SECONDARY SHORTWAVE WILL TRACK ACROSS THE DAKOTAS AND NEBRASKA THIS AFTERNOON. INHERITED FORECAST HAD SLIGHT CHANCE POPS LATER THIS MORNING AND THIS AFTERNOON ACROSS A LARGE CHUNK OF CENTRAL AND NORTH CENTRAL NEBRASKA. DECIDED TO SCALE THIS BACK SOMEWHAT TO MAINLY SPRINKLES...AND ISOLATED SHOWERS DURING THE MID TO LATE AFTERNOON HOURS. FCST SOUNDINGS ACROSS THE CENTRAL AND NRN CWA...CONTINUE TO INDICATE VERY DRY CONDS IN THE SURFACE TO 5000-7000 FT AGL LAYER...WITH LAYER PW`S A MERE .3 INCHES...SO FEEL SPRINKLES ARE WARRANTED HERE. ACROSS FAR NORTHEASTERN AREAS...WILL CONTINUE ISOLATED SHOWERS DURING THE MID TO LATE AFTERNOON HOURS...AS STEEP LAPSE RATES REMAIN IN PLACE...AND MOISTURE IS A LITTLE BETTER ACROSS THE NORTHEASTERN CWA. HIGHS THIS AFTERNOON WILL RANGE FROM THE UPPER 40S IN THE NORTHWEST...TO THE LOWER 50S ELSEWHERE. FOR TONIGHT...THE UPPER LEVEL SHORTWAVE...WILL SLIDE EAST OF THE FORECAST AREA LEADING TO CLEARING SKIES IN THE CENTRAL AND WEST...AS WELL AS COLD TEMPERATURES. WITH DRY AIR IN PLACE AND FAIRLY LIGHT WESTERLY WINDS...LOWS WILL BOTTOM OUT MID TO UPPER 20S IN THE WEST...AROUND 30 IN THE CENTRAL AND LOWER 30S IN THE NORTHEAST WHERE CLOUD COVER WILL BE MORE PREVALENT. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 333 AM CDT FRI OCT 18 2013 SATURDAY AND SUNDAY THE EASTERN PAC RIDGE WILL SLOWLY SHIFT ONSHORE AND BEGIN TO AMPLIFY...NOSING INTO WESTERN CANADA. FLOW BECOMES NORTHWESTERLY THEN MORE NORTHERLY. A LONG WAVE TROUGH WILL SET UP ACROSS THE GREAT LAKES REGION. THIS WILL BRING AN ACTIVE PATTERN WITH SEVERAL DISTURBANCE TO MOVE ACROSS THE NORTHERN PLAINS. TWO MAJOR CONCERNS WITH THE FORECAST FOR THE WEEKEND INTO NEXT WEEK. AVAILABILITY OF MOISTURE IS ONE. 00Z KLBF SOUNDING LAST NIGHT ONLY HAD 0.37 INCHES OF PWATS...AND NW FLOW WILL CONTINUE TO LIMIT MOISTURE RETURN. EACH PASSING DISTURBANCE WILL SEE STEEP LAPSE RATES AND POCKETS OF GOOD FRONTOGENESIS...HOWEVER LACK OF MOISTURE IS EXPECTED TO RESULT IN ONLY PASSING CLOUDS AND ISOLATE LIGHT RAIN/SNOW SHOWERS. GENERALLY LIQUID DURING THE DAYTIME...WHILE OVERNIGHT MAY SEE A MIX OF RAIN AND SNOW AS TEMPS DROP INTO THE LOWER TO MID 30S. TIMING OF WAVES IS SUNDAY AND ANOTHER SUNDAY NIGHT INTO MONDAY...FOLLOWED BY ONE MORE ON TUESDAY. THE RIDGE BY MID WEEK WILL BEGIN TO PUSH THE WAVES FURTHER EAST AND SHOULD SEE DRY CONDITIONS PREVAIL FOR REST OF THE WEEK. THE SECOND CONCERN FOCUSES ON TEMPERATURES. COLD AIR WILL DEFINITELY BE DRAW OVER THE GREAT LAKES...WHILE WARM AIR BUILDS ACROSS THE SW CONUS. THE HIGH PLAINS WILL BE IN THE BATTLE GROUND WITH TEMPS HIGHLY DEPENDENT ON CLOUD COVER AND THE WESTWARD PUSH OF THE COLD AIR. THE MODELS ARE STRUGGLING WITH THE COLD AIR AT THE SFC NEXT WEEK...EVIDENT BY THE LATEST MEX GUIDANCE. TUESDAY MOS GUIDANCE TEMPS JUMPED FROM UPPER 40S TO LOWER 50S...TO THE LOWER AND MID 60S. OVER THE WEEKEND NOT EXPECTING TO MUCH VARIATION FROM MOS GUIDANCE AS POCKETS OF CLOUDS TO KEEP HIGHS AT OR BELOW SEASONAL NORMALS...MID TO UPPER 50S. BY MID WEEK...AS THE UPPER LEVEL RIDGE INCREASES HEIGHTS...TEMPS SHOULD GO UP. WOULD BE MORE CONCERNED ABOUT THE COLD AIR REMAINING IN PLACE IF THERE WAS A SNOW PACK...HOWEVER WITH NOT SNOW WILL FAVOR A UPWARD TREND IN THE FORECAST...TRENDING TOWARDS THE NEW GFS SOLUTION. STILL WOULD LIKE TO SEE MORE CONSISTENCY WITH THE MODELS AS CONFIDENCE IS LOW FOR THE MID NEXT WEEK FORECAST. TUESDAY AND WEDNESDAY MODEL 850 MB TEMPS HAVE A RANGE OF MORE THAN 10 DEGREES C AMONGST THE MANY MEMBERS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 634 AM CDT FRI OCT 18 2013 AN UPPER LEVEL TROUGH OF LOW PRESSURE WILL TRACK ACROSS THE DAKOTAS AND NEBRASKA TODAY AND THIS EVENING...SPREADING ABUNDANT MID LEVEL CLOUDINESS TO WESTERN AND NORTH CENTRAL NEBRASKA. FOR THE KVTN TERMINAL...BROKEN CIGS AROUND 5000 FT AGL WILL BE POSSIBLE THROUGH THIS AFTERNOON WITH BROKEN CIGS AROUND 10000 FT AGL EXPECTED TONIGHT. FOR THE KLBF TERMINAL...BROKEN CIGS RANGING FROM 7000 TO 15000 FT AGL ARE EXPECTED TODAY...WITH SCATTERED HIGH CLOUDINESS POSSIBLE OVERNIGHT. WINDS TODAY WILL BE FROM THE WEST NORTHWEST AT 10 TO 20 KTS...DECREASING TO UNDER 10 KTS TONIGHT. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JACOBS SYNOPSIS...CLB SHORT TERM...CLB LONG TERM...MASEK AVIATION...CLB
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1158 AM MDT FRI OCT 18 2013 .AVIATION... 18Z TAF CYCLE EXPECTING MVFR/IFR CIGS FOR KTCC...KLVS AND REMAINDER OF EASTERN PLAINS CENTRAL HIGHLANDS THROUGH LATE EVENING AS A SHALLOW BACKDOOR COLD FRONT TRAVELS WSW TOWARD THE CENTRAL MTN CHAIN AND ACROSS THE SE PLAINS. KABQ WILL EXPERIENCE BRIEF EASTERLY CANYON WINDS BETWEEN 03 AND 06Z. GUSTY NE WINDS BEHIND THE FRONT FOR KROW THIS AFTERNOON. AS THE SFC HIGH SHIFTS SOUTHWEST LATE TONIGHT INTO TOMORROW MORNING WINDS WILL DECREASE AS WEAKENING SFC HIGH TRAVELS SE INTO SOUTHERN TX. 33 && .PREV DISCUSSION...330 AM MDT FRI OCT 18 2013... SFC LOW/TROUGH ACROSS FAR EAST CENTRAL NM AND INTO THE ADJACENT PORTION OF TX HAS CIRCULATED LOW LEVEL MOISTURE INTO SE NM WITH ATTENDANT LOW CLOUDS/FOG OVER LEA/EDDY AND SE ROOSEVELT COUNTIES...WHICH IS FARTHER WEST THAN WAS INDICATED 24 HRS AGO. EXPECT THIS WILL MAKE A LITTLE MORE PROGRESS NORTH AND WWD BEFORE THE COLD FRONT...CURRENTLY FROM CAO TO RTN...AND WITH IT/S STRATUS...PUSHES FARTHER SOUTH. RUC INDICATES THE MOISTURE IN THE SOUTHEAST SHOULD EXIT BY MID MORNING WHILE THE STRATUS CONTINUES TO INVADE THE NE AND TO SOME EXTENT THE EAST CENTRAL. TODAY/S AREAL COVERAGE OF POPS DIDN/T CHANGE MUCH FROM PREVIOUS MODEL RUNS. FORECAST HIGHS HOWEVER DID COOL SEVERAL DEGREES IN THE NORTHEAST AND EAST CENTRAL NO DOUBT IN PART TO THE EXTENSIVE LOW CLOUDS THAT MAY LINGER THROUGH EARLY/MID AFTERNOON ACCORDING TO THE RUC. THE AREA FROM RATON TO CLAYTON MAY NOT GET ANY WARMER THAN MID 40S...WHICH IS 20 TO 25 DEGREES BELOW NORMAL IF THE GUIDANCE IS CLOSE. OVERALL HIGHS TODAY RANGE FROM NEAR NORMAL FAR SOUTHWEST TO 10 TO 15 DEGREES BELOW AVERAGE FAR NORTHWEST TO THE FAR SOUTHEAST. THE COOLER THAN AVERAGE HIGHS SET THE STAGE FOR POTENTIAL FOR NEAR TO BELOW FREEZING LOWS TONIGHT. GUIDANCE FOR PORTIONS OF THE EAST CENTRAL CLOSER TO THE TX BORDER AND ROW AREAS HAS COOLED A COUPLE MORE DEGREES...SO A FREEZE WATCH WILL BE ISSUED. SOME LOW LEVEL MOISTURE MAY BE PARKED ALONG THE EAST SLOPES OF THE CENTRAL MT CHAIN THIS EVENING BUT DEWPOINTS STILL EVENTUALLY LOWER SUFFICIENTLY FOR THE THREAT OF A FREEZE. MODELS NOW INDICATE AT LEAST SOME POTENTIAL FOR AN EAST WIND TO BREAK INTO THE MIDDLE RGV THIS EVENING...WHICH COMPLICATES A FREEZE/NO FREEZE DECISION THAT MUCH MORE ESPECIALLY IN THE ABQ METRO. CURRENT THOUGHTS ARE THE WIND COULD DIMINISH AFTER MIDNIGHT...SO DECIDED TO ISSUE A FREEZE WATCH FOR THE MIDDLE AND LOWER RGV AS WELL AS FOR THE UPPER TULAROSA VALLEY...WHERE SOME LOCALES HAVE NOT YET FROZEN. FOR THE REST OF THE WEEKEND...A WARMING TREND WILL COMMENCE WITH HIGHS ACHIEVING NEAR NORMAL STATUS SUNDAY. ANOTHER FRONT COULD ARRIVE IN THE EASTERN PLAINS AS SOON AS LATE SUNDAY...SO HIGHS WILL BE KNOCKED DOWNWARD MONDAY. THIS FRONT LOOKS MORE LIKELY TO PRODUCE AN EAST WIND INTO THE RGV EARLY MONDAY. EXTENDED FORECAST MODEL TRENDS FOR MID TO LATE NEXT WEEK LEAN TOWARDS MORE OF A RIDGE OVER NEW MEXICO. LATEST ECMWF DEPICTS A DECENT SFC HIGH INVADING ERN NM DESPITE THE RIDGE WHILE THE GFS LOCATES IT WELL TO THE EAST...WREAKING HAVOC ON FORECAST TEMPERATURE DECISIONS. BOTH GFS AND ECMWF INDICATE A WEAK DISTURBANCE TRACKING INTO WRN NM FROM THE WEST AROUND THURSDAY OF NEXT WEEK...NOT CONFIDENT AT ALL IT WILL AMOUNT TO MUCH. IN ANY CASE WENT CLOSER TO THE ECMWF SOLUTION FOR TEMPS AND WITH A GFS/ECMWF BLEND FOR POPS. .FIRE WEATHER... COOLER AIR WILL INVADE NEW MEXICO TODAY AS NORTHWEST FLOW ALOFT DRAGS A TROUGH INTO THE STATE ALONG WITH A BACK DOOR SURFACE FRONT. THE PLAINS WILL OBSERVE THE SHARPEST TEMPERATURE DIFFERENTIAL FROM YESTERDAY ALONG WITH GUSTY NORTHEAST WINDS THROUGH THE DAY AS THE FRONT SPILLS IN. THE CENTRAL TO WESTERN ZONES WILL ALSO BECOME BREEZY TO WINDY WITH A NORTHWESTERLY DIRECTION. SURFACE GRADIENT APPEARS A BIT STRONGER THAN PREVIOUS MODEL RUNS WERE ADVERTISING...SO FORECAST SPEEDS WERE INCREASED TO REFLECT THIS. VENTILATION RATES LOOK TO REMAIN GOOD TO EXCELLENT WITH THESE STRONGER BOUNDARY LAYER BREEZES...BUT WINDS DO NOT APPEAR TO BE CRITICALLY HIGH. DEWPOINTS DROP INTO THE LOWER TEENS AND SINGLE DIGITS IN THE WEST CENTRAL TO SOUTHWESTERN ZONES OF THE FORECAST AREA THIS AFTERNOON...DROPPING MINIMUM RH TO 12 TO 15 PERCENT. THIS AREA OF CRITICALLY LOW RH WILL NOT BE JUXTAPOSED OVER THE AREA WHERE THE STRONGEST WINDS WILL BE...AND THE COOLER TEMPERATURE REGIME DOES NOT FIT INTO THE MOLD OF A CRITICAL FIRE WEATHER EVENT EITHER. MAX TEMPERATURES WILL RUN ABOUT 8 TO 20 DEGREES BELOW NORMAL IN MOST AREAS TODAY. BETTER RH RECOVERY IS EXPECTED TONIGHT WITH COOLER TEMPERATURES. DEWPOINTS MAY LOWER A BIT IN THE PLAINS BY TONIGHT...BUT THEY WILL ACTUALLY RISE A BIT IN THE CENTRAL AREAS OF THE STATE. THIS WILL ALLOW MOST OF THE NORTHERN AND EASTERN TIERS OF THE STATE TO OBSERVE EXCELLENT RH RECOVERY WHILE CENTRAL TO WESTERN ZONES STAY IN THE FAIR TO GOOD CATEGORIES. ANOTHER SIGNIFICANT ASPECT OF TONIGHT/S FORECAST WILL BE THE POTENTIAL FOR FREEZING TEMPERATURES IN MUCH OF THE EAST CENTRAL PLAINS WHERE THE FREEZING MARK HAS YET TO BE REACHED. THIS WILL EXACERBATE FINE FUEL CURING. THERE WILL ALSO BE POTENTIAL FOR FREEZING TEMPERATURES ALONG THE MIDDLE RIO GRANDE AND TULAROSA VALLEYS...PRIMARILY IN THE LOWEST ELEVATIONS. SOME OF THESE VALLEY AREAS HAVE FLIRTED WITH FREEZING ON A COUPLE OF OCCASIONS THIS SEASON...BUT A WIDESPREAD HARD FREEZE HAS STILL NOT HAPPENED. NORTHWEST FLOW WILL NOT BE AS STRONG ON SATURDAY...AND ONLY SOME ISOLATED BREEZY TO WINDY CONDITIONS ARE EXPECTED OVER THE CENTRAL HIGHLANDS. TEMPERATURES WILL WARM A FEW DEGREES IN MOST OF THE FORECAST AREA AND SEVERAL DEGREES IN THE NORTHEASTERN PLAINS...BUT STILL DAYTIME HIGHS IN ALL AREAS WILL FALL JUST SHY OF CLIMATOLOGY. LOWEST DEWPOINTS WILL STAY CONFINED TO WEST CENTRAL NM SATURDAY...BUT THESE WILL MIX AND ADVANCE EASTWARD INTO SUNDAY. THIS WILL SPREAD SOME CRITICAL RH OVER THE CENTRAL HIGHLANDS WHERE A BRIEF BOUT OF CRITICAL WINDS WILL ALSO DEVELOP SUNDAY AFTERNOON. THE NEXT COLD FRONT WILL ARRIVE SUNDAY NIGHT AND INTO MONDAY MORNING. THIS BOUNDARY WILL LIKELY ADVANCE BEYOND THE CENTRAL MOUNTAIN CHAIN AND INTO THE RIO GRANDE VALLEY...PRODUCING SOME GUSTY WINDS ALONG THE BOUNDARY AND THROUGH CENTRAL GAPS/CANYONS WHILE TEMPERATURES PLUMMET BACK BELOW AVERAGE. OVERALL A DRIER AND MORE TRANQUIL PATTERN IS EXPECTED THROUGH TUESDAY AND WEDNESDAY OF NEXT WEEK...HOWEVER THERE IS SOME UNCERTAINTY REGARDING ANOTHER POTENTIAL FRONT. FORECAST MODELS HAVE DIFFERING NOTIONS ON HOW THE UPPER RIDGE WILL BREAK DOWN...AND MODELS HISTORICALLY HAVE SOME NOTORIOUS DEFICIENCIES IN THESE HIGH AMPLITUDE PATTERNS. 52 && .ABQ WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR THE FOLLOWING ZONES...NMZ519-520-525-533>538. && $$ SHY
AREA FORECAST DISCUSSION...COR
NWS WILMINGTON NC
335 PM EDT FRI OCT 18 2013 .SYNOPSIS... A WAVE OF LOW PRESSURE WILL LIFT NORTHEAST ALONG A STALLED COLD FRONT OVER THE COASTAL CAROLINAS TONIGHT INTO EARLY SATURDAY. HIGH PRESSURE WILL FORCE THE FRONT TO OUR SOUTH SUNDAY AND MONDAY. THE FRONT MAY RETURN NORTHWARD AS HIGH PRESSURE MOVES OFFSHORE MONDAY NIGHT INTO TUESDAY. A LARGE AREA OF COOL HIGH PRESSURE WILL SLOWLY BUILD INTO THE AREA LATE NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 3 PM FRIDAY...A SLOW EVOLUTION OF SHOWERS HAS MATERIALIZED SO FAR ACROSS THE REGION...REMAINING ISOLATED THIS AFTERNOON AND TRACKING PRIMARILY ACROSS OUR CENTRAL ZONES FROM SW TO NE. RAIN PROBABILITIES AND QPF BOTH WILL TAKE A TURN UPWARD TONIGHT AS A WAVE OF LOW PRESSURE TRACKS NE ALONG OUR COAST LATE TONIGHT INTO EARLY SATURDAY. THIS DEVELOPING AREA OF LOW PRESSURE HAS EMERGED AND CURRENTLY IS POSITIONED ALONG THE SE GEORGIA COAST. A RIBBON OF ENHANCED PRECIPITABLE WATERS REMAINED STRETCHED ALONG THE GA/SC COAST...TROPICAL MOISTURE REMNANTS OF FORMER PACIFIC SYSTEM OCTAVE. FORCING AND INSTABILITY HAS REMAINED FEEBLE ACROSS THE AREA AND THIS WILL CONTINUE INTO EVENING. CONVERGENCE HOWEVER WILL BE ON THE UPSWING LATE TONIGHT THROUGH DAYBREAK SATURDAY AS THE LOW PRESSURE WAVE NEARS AND TRACKS UP OUR COAST. THIS SHOULD TAP INTO A RICH MOISTURE SOURCE TO PRODUCE MORE WIDESPREAD AND HEAVIER SHOWERS. SINCE THE WAVE WILL TRACK NEAR AND ALONG THE COAST LATE TONIGHT...THIS IS WHERE WE HAVE FAVORED THE HIGHER POP VALUES. A MYRIAD OF QPF SOLUTIONS ARE OFFERED BUT BY CONSENSUS AND WPC DEPICTIONS 0.25-0.50" INCHES OF RAIN REMAINS A GOOD BET ALONG OUR COASTAL ZONES THROUGH DAYBREAK SATURDAY...WITH LESS AMOUNTS AND MORE STRATIFORM TYPE -RA FARTHER INLAND AWAY FROM THE PASSING WAVE. MINIMUMS SHOULD HOLD IN THE LOW TO MIDDLE 60S NEAR THE COAST IN BETTER MIXING...WHILE DEEP INLAND AN INVERSION AND LOW-LEVEL COOLING WILL BRING TEMPERATURES INTO THE UPPER 50S BY DAYBREAK SATURDAY. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 3 PM FRIDAY...WE WILL SEE A COMPLETE TRANSITION TO A DRIER AND MORE FALL LIKE AIR MASS BY THE LATTER HALF OF THE WEEKEND. THE FRONT STALLED ALONG THE COAST SATURDAY WILL GET A PUSH TO THE SOUTHEAST BY SATURDAY NIGHT WITH COOLER AND DRIER AIR ADVECTING IN OVERNIGHT SAT INTO SUNDAY. GFS SHOWS A SECONDARY COLD FRONT EXTENDING DOWN FROM THE GREAT LAKES SAT EVENING. THIS FRONT WILL PUSH SOUTHEAST DRIVING THE STALLED BOUNDARY TO THE SOUTHEAST AS HIGH PRESSURE AT THE SURFACE BUILDS IN BEHIND IT BY SUNDAY. STRONG LOW TO MID LEVEL WINDS OUT OF THE SOUTHWEST WILL KEEP A DEEPER MOISTURE FEED INTO THE AREA THROUGH MUCH OF SAT ....MAINLY ALONG THE COAST. THIS WILL COMBINE WITH SOME UPPER LEVEL DYNAMICS TO ENHANCE CHC OF PCP THROUGH AT LEAST EARLY SAT AFTN. THEREFORE WILL KEEP CLOUDS AND POPS UP THROUGH EARLY SAT AFTN AS PCP WATER VALUES REMAIN OVER 1.75 INCHES ALONG THE COAST. EXPECT GREATEST CHC ALONG THE COAST AND WILL SHOW A GRADIENT TO LOWER END POPS INLAND. EXPECT DRYING TREND THROUGH SAT AFTN INTO SUNDAY. AS BROAD MID TO UPPER TROUGH GIVES SECONDARY BOUNDARY A PUSH FROM THE NW...WINDS WILL VEER AROUND IN THE LOW TO MID LEVELS BECOMING W-NW AND NORTHERLY AT THE SURFACE THROUGH SAT NIGHT. THIS WILL BRING PLENTY OF DRY AIR INTO AREA THROUGH THE LOW TO MID LEVELS. PCP WATER VALUES DROP DOWN TO LESS THAN A HALF INCH THROUGH SUN MORNING. THE NORTHERLY SURGE OF DRY AND COOL AIR WILL BRING A GOOD 15 TO 20 DEGREE DROP IN DEWPOINT TEMPS. DEWPOINT TEMPS IN THE MID 60S EARLY SATURDAY WILL DROP TO LESS THAN 50 DEGREES BY SUNDAY WITH THE NAM SHOWING VALUES IN THE 30S. THE WINDS ALOFT WILL REMAIN MORE WESTERLY THROUGH THE PERIOD AS BROAD UPPER TROUGH LIFTS TO THE NORTHEAST AND RIDGE BUILDS UP FROM FLORIDA. THIS WILL PRODUCE PLENTY OF DRY AIR AND SUBSIDENCE IN THE MID LEVELS WITH A COOL NORTHERLY FLOW AT THE SURFACE KEEPING A SHALLOW COOL AIR MASS IN PLACE ON SUNDAY. THE BROAD UPPER LEVEL FLOW OUT OF THE W-SW WILL ALLOW SOME HIGH LEVEL MOISTURE AND CIRRUS CLOUDS TO STREAM IN...BUT OVERALL EXPECT A DRY FALL LIKE SUNDAY. THE SURFACE HIGH WILL PROGRESS SLOWLY EAST THROUGH EARLY MONDAY KEEPING A COOL N-NE WIND FLOW. EXPECT FAIRLY DECENT RADIATIONAL COOLING SUNDAY NIGHT IN CLEAR SKIES AND VERY LIGHT WINDS. THE GRADIENT MAY REMAIN SLIGHTLY MORE PINCHED ALONG THE COAST ALLOWING WINDS TO SPIKE UP OVERNIGHT WHICH IN TURN MAY COMBINE WITH WATER TEMPS AROUND 70 TO KEEP TEMPS RIGHT ALONG THE COAST A LITTLE HIGHER BUT OVERALL EXPECT TEMPS TO DROP OUT SUNDAY NIGHT WITH READINGS MAKING IT DOWN NEAR 50 AND SOME 40S IN TRADITIONALLY COOLER SPOTS ACROSS THE FORECAST AREA. THEREFORE TEMPS WILL START OUT IN THE MID TO UPPER 70S ON SAT IN CLOUDS AND SHOWERS AND WILL END IN THE LOW TO MID 70S IN A DRY AND COOLER AIR MASS ON SUNDAY. && .LONG TERM /MONDAY THROUGH FRIDAY/... AS OF 300 PM FRIDAY...FIRST COLD OUTBREAK OF THE YEAR ANTICIPATED AT THE END OF THE PERIOD AS A STRONG VORT AND COLD FRONT DIVE ACROSS THE EASTERN HALF OF THE CONUS. ONLY CHANCE FOR PRECIP OCCURS LATE MONDAY AND TUESDAY. A WAVE OF LOW PRESSURE BENEATH A WEAK VORT IMPULSE DEVELOPS ALONG A BOUNDARY STALLED OFFSHORE. THIS LOW PUSHES THE FRONT BACK TOWARDS THE COAST...AND ASSOCIATED THETA-E RIDGING AND COLUMN SATURATION OCCURS FROM SE TO NW. THIS PROMOTES THE POTENTIAL FOR LIGHT RAIN ACROSS THE AREA...HIGHEST CHANCES ACROSS THE EASTERN HALF OF THE CWA. GFS AND ECMWF DIFFER IN STRENGTH AND COVERAGE OF RAINFALL...AND WILL LEAN ON THE DRIER ECMWF WHICH KEEPS THE MAJORITY OF THE RAINFALL OFFSHORE. STILL...LATE MONDAY INTO EARLY WED WILL BE UNSETTLED WITH CLOUDS/SHOWERS/AND TEMPS AROUND CLIMO. SURGE OF COOL AIR PUSHES THE FRONT OFFSHORE BY WEDNESDAY...AND THIS WILL BE THE LEADING EDGE OF MUCH COOLER AIR FOR THE END OF THE WEEK. WHILE WEDNESDAY WILL BECOME SUNNY AND DRY...CAA THROUGH THE DAY WILL KEEP TEMPS BELOW CLIMO. STRONG VORT THEN DIVES TOWARDS THE AREA THURSDAY...AND IS REINFORCED ON FRIDAY. TEMPS WILL FALL TO WELL BELOW NORMAL...AND BOTH THE ECMWF/GFS SHOW THE 850MB 0C LINE APPROACHING THE NW CORNER OF THE CWA...WITH 1000-500MB THICKNESSES DROPPING INTO THE 550`S. MEX/ECE NUMBERS ARE ALREADY SUGGESTING LOWS FALLING INTO THE LOW 40S...AND THESE OF COURSE ARE BEING PULLED UP BY CLIMO. TOO SOON TO SETTLE ON SPECIFICS FOR THE END OF NEXT WEEK...BUT THE COLDEST AIR OF THE SEASON LOOKS LIKELY HEADING INTO NEXT WEEKEND. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... AS OF 18Z...FRONTAL BOUNDARY DRAPED OVER THE CWA WITH A MIXTURE OF LOW AND MIDDLE CLOUDS ONGOING. SKIES WILL BE PREDOMINATELY VFR THIS AFTERNOON...WITH AREAS OF MVFR. HRRR MODEL SHOWS A BAND OF LIGHT TO MODERATE CONVECTION DEVELOPING AND TRAVELING NORTHEAST THROUGH THE CENTRAL PORTION OF THE REGION. WENT WITH VCSH AT ALL TERMINALS DUE TO THE PROXIMITY OF THE CONVECTION. LIGHT NORTHEAST FLOW WILL BECOME SOUTHEASTERLY ALONG THE COAST. TONIGHT...SOME UNCERTAINTY WITH RESPECT TO CEILINGS. STARTING TO LEAN TO THE NAM WHICH IS MORE PESSIMISTIC WITH BOTH VISIBILITIES AND CEILINGS. COULD SEE SOME WIDESPREAD IFR CONDITIONS AFTER MIDNIGHT. SATURDAY...FRONTAL BOUNDARY WAVES BACK TO THE NORTH...WITH MAINLY STRATIFORM PRECIPITATION EXPECTED ALONG THE COAST WITH SHOWERS MOVING OFF TO THE NE THROUGH THE DAY. EXTENDED OUTLOOK...PRECIPITATION ENDING LATE SATURDAY. VFR DEVELOPING SUNDAY. LIGHT RAIN DEVELOPING TUESDAY MORNING INTO WEDNESDAY WITH DEVELOPING FRONTAL SYSTEM. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 3 PM FRIDAY...NO ADVISORIES PLANNED THROUGH DAYBREAK SATURDAY DESPITE A WAVE OF LOW PRESSURE IMPACTING THE COASTAL WATERS LATE TONIGHT. WINDS HOWEVER WILL BECOME CHANGEABLE WITH LIGHT SE FLOW EARLY THIS EVENING...BECOMING SW AND INCREASING TO 15 KT AND GUSTY AFTER MIDNIGHT AS THE WAVE CENTER MOVES NEAR CAPE FEAR. SEAS MAINLY 2-3 FEET OVERNIGHT BUT UP TO 4 FT OFFSHORE BETWEEN MIDNIGHT AND DAYBREAK SATURDAY. ISOLATED TSTMS WILL BE POSSIBLE OVERNIGHT ACROSS OUR COASTAL WATERS. SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 3 PM FRIDAY...A STALLED FRONT WILL KEEP WINDS WEST TO SOUTHWEST EARLY SATURDAY. AS A WAVE ALONG FRONT MOVES OFF TO THE NORTHEAST THE WINDS WILL SHIFT MORE WESTERLY THROUGH SAT AFTN, THEN A SECONDARY BOUNDARY MOVES IN FROM THE NW SAT NIGHT DRIVING THE STALLED FRONT TO THE SOUTH AND BRINGING WINDS AROUND TO THE NORTH TO NORTHEAST THROUGH SUNDAY. HIGH PRESSURE WILL BUILD INTO THE WATERS THROUGH SUNDAY MAINTAINING NORTHERLY WINDS THROUGH SUNDAY. MODELS SHOWING DECENT SHALLOW COOL AND DRY PUSH WHICH MAY KICK UP WITH THE SEAS A BIT IN NORTHERLY SURGE EARLY SUNDAY. FOR NOW WILL HOLD WINDS AT 10 TO 15 KTS BUT MAY SEE A LARGER SPIKE THROUGH SUNDAY INTO EARLY MONDAY. SEAS WILL SPIKE UP SAT MORNING AND AGAIN SUNDAY...BUT SHOULD REMAIN LESS THAN 4 FT. LONG TERM /MONDAY THROUGH WEDNESDAY/... AS OF 300 PM FRIDAY...SHIFTING WINDS MON AND TUE WILL FORTUNATELY REMAIN RATHER LIGHT...AROUND 10 KTS (ALTHOUGH BRIEF INCREASE TO 15 KTS POSSIBLE EARLY IN THE PERIOD)...SHIFTING FROM NE MUCH OF MONDAY...TO LIGHT AND VARIABLE...AND THEN W/NW ON TUESDAY. THESE SHIFTING WINDS ARE DUE TO A STALLED BOUNDARY WHICH WILL WAVER NEAR THE WATERS AS A WEAK LOW PRESSURE MOVES ALONG IT. AS THIS LOW MOVES AWAY ON WEDNESDAY...IT DRAGS THE FRONT BACK SE AS A COLD FRONT...WITH WINDS INCREASING TO 10-15 KTS FROM THE NW. WAVE HEIGHTS WILL BE 2-3 FT EACH DAY THROUGH THE PERIOD...BUT WITH A WIND WAVE SHIFTING TO FOLLOW THE MEAN DIRECTION EACH DAY. && .TIDES/COASTAL FLOODING... AS OF 3 PM FRIDAY...CFW ISSUED FOR THE CAPE FEAR AT DOWNTOWN WILMINGTON FOR MINOR FLOODING DUE TO ELEVATED ASTRONOMICAL TIDES. THIS WILL BE COINCIDENT WITH THIS EVENINGS HIGH TIDE AND THE ADVISORY WILL RUN FROM 9PM-11PM AS SEVERAL INCHES OF WATER BEGINS TO COVER WATER STREET AND THE BATTLESHIP AREA...AND OTHER LOW- LYING LOCATIONS ALONG THE LOWER CAPE FEAR RIVER. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...COASTAL FLOOD ADVISORY FROM 9 PM TO 11 PM EDT THIS EVENING FOR NCZ107. MARINE...NONE. && $$ NEAR TERM...MJC SHORT TERM...RGZ LONG TERM...JDW AVIATION...MJC/DL TIDES/COASTAL FLOODING...MJC
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
100 PM EDT FRI OCT 18 2013 .SYNOPSIS... A COLD FRONT WILL MOVE ACROSS THE AREA THIS MORNING AND THEN STALL JUST OFFSHORE AS A WAVE OF LOW PRESSURE DEVELOPS TO OUR SOUTH AND LIFTS NORTHEAST ALONG THE FRONT AND ACROSS THE AREA TONIGHT AND SATURDAY MORNING. HIGH PRESSURE WILL FORCE THE FRONT TO OUR SOUTH SUNDAY AND MONDAY. HIGH PRESSURE WILL MOVE OFFSHORE MONDAY NIGHT AND TUESDAY AND THIS MAY ALLOW THE FRONT TO OUR SOUTH TO RETURN NORTHWARD. A LARGE AREA OF COOL HIGH PRESSURE WILL SLOWLY BUILD INTO THE AREA LATE NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 10 AM FRIDAY...VARIABLE CLOUDINESS WILL STRADDLE THE CENTRAL ZONES THIS MORNING AS BREAKS IN THE OVERCAST SAIL SWIFTLY OVERHEAD FROM SW TO NE...BUT MOSTLY CLOUDY SKY CONDITION APPEARS STILL ON TARGET FOR TODAY. THE CLOUD BREAKS ARE DISCONCERTING WITH REGARD TO MAXIMUM TEMPERATURE FORECASTS TODAY...BUT MID AND MAYBE A FEW UPPER 70S STILL LOOKS GOOD SINCE SUNSHINE WILL NOT LAST LONG IN ANY ONE LOCATION. VWP SHOWING WSW WIND 20-30 KT BETWEEN 800-700 MB PRESENTLY. A RIBBON OF HIGH PRECIPITABLE WATER WAS STREAMING SW TO NE WITH TROPICAL REMNANTS OF PACIFIC SYSTEM OCTAVE IN THE MIX. CHS REPORTED 1.85 PWAT VALUES WITH THE 12Z UPPER AIR SOUNDING. FORCING WILL REMAIN WEAK TODAY WITH ISOLATED SHOWERS ANTICIPATED. FARTHER INLAND WEAK ISENTROPIC LIFT MAY RESULT IN LOWER CEILINGS AND -RA/DZ ALONG THE LEADING EDGE OF HIGH PRESSURE BUILDING IN BEHIND THE FRONT OVER OUR WESTERN AND NORTHERN ZONES...ALTHOUGH AGAIN LOW QPFS EXPECTED MUCH OF TODAY. TONIGHT UNFOLDS WITH A BUMP UPWARD IN RAIN CHANCES AND AMOUNTS AS LOW-LEVEL CONVERGENCE INCREASES IN VICINITY OF A WAVE OF SURFACE LOW PRESSURE ALONG THE FRONT. HOWEVER SINCE THIS FEATURE MAY RESIDE OVER THE COASTAL WATERS WHILE MIGRATING NE...SHOWERS SHOULD BECOME MOST FAVORED ALONG AND NEAR THE COASTAL ZONES TONIGHT INTO SATURDAY MORNING WHERE HIGHER RAINFALL AMOUNTS COULD OCCUR DUE TO THE RICH AMOUNTS OF MOISTURE AVAILABLE. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 3 AM FRIDAY...THE WEEKEND WILL SEE ONE WET DAY AND ONE DRY DAY AS A FRONT AND MID LEVEL FORCING IMPACT THE AREA SATURDAY. 0000 UTC GUIDANCE HAD TRENDED WETTER FOR SATURDAY ESPECIALLY ALONG COASTAL AREAS VIA MID LEVEL FORCING COMPRISED OF JET DYNAMICS COUPLED WITH A SURFACE FRONT. MOISTURE PROFILES HAVE SHAPED UP AS WELL WITH PRECIPITABLE WATER VALUES NEARING TWO INCHES ALBEIT BRIEFLY ALONG THE COAST. THIS SEEMS PLAUSIBLE LOOKING AT WATER VAPOR LOOPS UPSTREAM. I INCREMENTALLY INCREASED THE ALREADY LIKELY POPS ALONG THE COAST TO REPRESENT THIS TREND AND INCREASED POPS TO CHANCE INLAND. THE BIG DIFFERENCE WILL BE QPF AMOUNTS WHICH WILL LIKELY BE PALTRY INLAND BUT THE COASTAL AREAS COULD SCORE ONE HALF TO ONE INCH. MODELS HAVE TRENDED DRIER FOR SUNDAY AND HAVE REMOVED ANY MENTION OF POPS FOR SUNDAY AND SCALED BACK CLOUD COVER. HOWEVER WITH THE SUBTROPICAL JET/SOUTHWEST FLOW INTACT AREAS OF MID AND HIGH LEVEL CLOUDS WILL PRECLUDE A SUNNY TO MOSTLY SUNNY DAY. I MADE ONLY MINOR MODIFICATIONS TO THE TEMPERATURE FORECAST WALKING BACK HIGHS SATURDAY CITING THE INCREASED POPS. JUST THE OPPOSITE FOR SUNDAY WITH DRIER CONDITIONS THEREFORE I TRENDED SLIGHTLY WARMER. && .LONG TERM /MONDAY THROUGH THURSDAY/... AS OF 3 AM FRIDAY...MEDIUM RANGE GUIDANCE CONTINUES TO SHOW A BROAD CYCLONIC FLOW ACROSS THE LOWER 48 THROUGH THE PERIOD. WE MAY GET BRUSHED BY A SYSTEM THAT MOVES QUICKLY THROUGH THE SUBTROPICAL JET LATE MONDAY AND TUESDAY AND LOW CHANCE POPS REMAIN IN THE FORECAST FOR THIS TIME. INLAND COUNTIES MAY NOT SEE ANY IMPACTS FROM THIS FEATURE. AFTER THIS A POTENT VORT DEEPENS THE LONG WAVE TROUGH AND BRINGS ALONG WITH IT SOME OF THE COOLEST AIR OF THE SEASON. 850MB TEMPERATURES AT LEAST FROM THE GFS DROP TO JUST OVER THE FREEZING LEVEL. AS USUAL A MIXED BOUNDARY LAYER WILL MITIGATE MORNING LOWS BUT PROBABLY A BIT TOO FAR OUT IN TIME TO FINE TUNE TEMPERATURES IN DEPTH. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... AS OF 18Z...FRONTAL BOUNDARY DRAPED OVER THE CWA WITH A MIXTURE OF LOW AND MIDDLE CLOUDS ONGOING. SKIES WILL BE PREDOMINATELY VFR THIS AFTERNOON...WITH AREAS OF MVFR. HRRR MODEL SHOWS A BAND OF LIGHT TO MODERATE CONVECTION DEVELOPING AND TRAVELING NORTHEAST THROUGH THE CENTRAL PORTION OF THE REGION. WENT WITH VCSH AT ALL TERMINALS DUE TO THE PROXIMITY OF THE CONVECTION. LIGHT NORTHEAST FLOW WILL BECOME SOUTHEASTERLY ALONG THE COAST. TONIGHT...SOME UNCERTAINTY WITH RESPECT TO CEILINGS. STARTING TO LEAN TO THE NAM WHICH IS MORE PESSIMISTIC WITH BOTH VISIBILITIES AND CEILINGS. COULD SEE SOME WIDESPREAD IFR CONDITIONS AFTER MIDNIGHT. SATURDAY...FRONTAL BOUNDARY WAVES BACK TO THE NORTH...WITH MAINLY STRATIFORM PRECIPITATION EXPECTED ALONG THE COAST WITH SHOWERS MOVING OFF TO THE NE THROUGH THE DAY. EXTENDED OUTLOOK...PRECIPITATION ENDING LATE SATURDAY. VFR DEVELOPING SUNDAY. LIGHT RAIN DEVELOPING TUESDAY MORNING INTO WEDNESDAY WITH DEVELOPING FRONTAL SYSTEM. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 10 AM FRIDAY...A COLD FRONT WILL STALL NEAR THE COAST AS A WAVE OF LOW PRESSURE BEGINS TO DEVELOP TO OUR S LATER TODAY. THE FRONT WILL LIKELY RETROGRADE SLIGHTLY AS THE WAVE MIGRATES NE ACROSS THE AREA TONIGHT. THIS WILL MAKE FOR A DIFFICULT WIND DIRECTION FORECAST. WINDS ARE EXPECTED TO VEER TO THE N LATER THIS MORNING. WINDS WILL BE FROM THE NE OR ENE FOR THE AFTERNOON HOURS AND THEN VEER ALL THE WAY AROUND TO S AND SW OVERNIGHT. WIND SPEEDS WILL BE 10 KT OR LESS...PERHAPS AS HIGH AS 10 TO 15 KT TOWARD MORNING ACROSS THE OUTER WATERS ALONG AND AHEAD OF THE WAVE OF LOW PRESSURE. SEAS WILL BE 2 TO 3 FT...WITH AROUND 4 FT AT FRYING PAN SHOALS BUOY. SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 3 AM FRIDAY...A STALLED FRONT WILL KEEP WINDS WEST TO SOUTHWEST EARLY SATURDAY. AS A WAVE DEVELOPS AND MOVES TO THE NORTHEAST OF THE AREA LATER IN THE DAY...WINDS WILL TAKE A MORE CONSISTENT WESTERLY DIRECTION. WITH CLOUD COVER KEEPING SURFACE TEMPERATURES IN CHECK...THE SEABREEZE SHOULD NOT DEVELOP. SPEEDS WILL HOVER AROUND TEN KNOTS. HIGH PRESSURE...INITIALLY OVER THE TENNESSEE VALLEY MOVES CLOSER SUNDAY TURNING WINDS TO THE NORTHEAST. WITH SUBTLE COLD AIR ADVECTION...SPEEDS INCREASE TO 10-15 KNOTS BUT PROBABLY MORE TOWARD THE LOWER END OF THE RANGE. LONG TERM /MONDAY THROUGH TUESDAY/... AS OF 3 AM FRIDAY...INITIALLY WINDS WILL BE FROM THE NORTHEAST ACROSS THE COASTAL WATERS IN A RANGE OF 10-15 KNOTS. WIND FIELDS WILL DECREASE THROUGH THE DAY MONDAY INTO TUESDAY MORNING AS THE GRADIENT WEAKENS CONSIDERABLY. LOW PRESSURE WILL MOVE WELL OFFSHORE DURING THIS TIME. WINDS MAY NEED TO BE ADJUSTED DEPENDING ON THE EXACT TRACK AND STRENGTH OF THIS FEATURE. A NORTHERLY FLOW WILL ENSUE AFTER THE LOW MOVES BY AT THE END OF THE PERIOD. MODEST WIND FIELDS CONTINUE TO EQUATE TO MINIMAL SEAS WITH GENERALLY 1-3 FEET. && .TIDES/COASTAL FLOODING... AS OF 3 AM FRIDAY...A COASTAL FLOOD ADVISORY IS IN EFFECT THIS MORNING FOR PORTIONS OF THE CAPE FEAR RIVER. THE DOWNTOWN WILMINGTON TIDE GAUGE IS EXPECTED TO PEAK AT ABOUT 6 FT. HIGH TIDE ALONG THE RIVER IS AT 930 AM. ALONG THE BEACHES...WATER LEVELS WILL BE ELEVATED ONCE AGAIN AND ACTION STAGES WILL LIKELY BE REACHED. HOWEVER... GAUGES ARE NOT EXPECTED TO REACH MINOR COASTAL FLOOD THRESHOLDS. HOWEVER...THERE MAY BE A FEW VERY LOW SPOTS NEAR THE IMMEDIATE COAST THAT EXPERIENCE PONDING OF SALT WATER BETWEEN 630 AND 830 AM AS THE WATER COMES WELL UP ONTO THE BEACHES. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...MJC SHORT TERM...SHK LONG TERM...SHK AVIATION...DL/MJC TIDES/COASTAL FLOODING...RJD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
524 PM CDT FRI OCT 18 2013 .UPDATE... ISSUED AT 524 PM CDT FRI OCT 18 2013 LATEST WATER VAPOR SHOWS A SHORTWAVE ALONG THE SOUTHERN SASKATCHEWAN AND MANITOBA BORDER DIVING SOUTH WITH TIME. AN AREA OF VERTICAL MOTION/H85-H3 OMEGA AHEAD OF THIS WAVE CONTINUES TO RESULT IN SURFACE PRESSURE FALLS AND SCATTERED RAINSHOWERS IN NORTH CENTRAL NORTH DAKOTA. THE LATEST HRRR FORECASTS THIS AREA TO SHIFT SOUTH AND INCREASE IN AREAL COVERAGE FOR SOUTH CENTRAL NORTH DAKOTA THROUGH 04Z. CONCUR WITH THIS IDEA PER LATEST RADAR RETURNS. THERE COULD BE SOME SNOW OR GRAUPEL WITHIN HEAVIER CONVECTIVE SHOWERS THIS EVENING AS THE SHALLOW SURFACE WARM LAYER COOLS WITH SUPERCOOLED WATER DROPLETS DOMINATING ABOVE. MAIN FORECAST REMAINS ON TRACK WITH MINOR UPDATES TO HOURLY GRIDDED DATA. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 251 PM CDT FRI OCT 18 2013 SMALL POCKETS OF LIGHT RAIN WILL CONTINUE TO DEVELOP AND PUSH SOUTHEAST THROUGH THE AFTERNOON HOURS. THE HIGHEST PRECIPITATION COVERAGE IS EXPECTED NORTHEAST OF A LINE FROM KENMARE TO BISMARCK AND ELLENDALE. AS NEAR SURFACE TEMPS DROP OFF TONIGHT...EXPECT RAIN TO BECOME MIXED WITH OR CHANGE OVER TO ALL SNOW. THERE MAY BE SOME VERY MINOR ACCUMULATIONS ON GRASSY SURFACES...MAINLY FROM BOTTINEAU...TO CARRINGTON AND JAMESTOWN. ON SATURDAY...A WARM FRONT WILL PUSH INTO WESTERN NORTH DAKOTA DURING THE MORNING HOURS. A BAROCLINIC ZONE NEAR THE BOUNDARY MAY BE ENOUGH TO SUPPORT A FEW LIGHT SNOW SHOWERS...MAINLY DURING THE MORNING HOURS. AGAIN...LITTLE OR NO ACCUMULATION IS EXPECTED. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 251 PM CDT FRI OCT 18 2013 THE LONG TERM FORECAST WILL BE DOMINATED BY NORTH/NORTHWEST FLOW ALOFT WITH A TROUGH OVER EASTERN CANADA/US AND A WESTERN RIDGE OVER WESTERN CANADA/US. THE MAIN FOCUS IN THE LONG TERM WILL BE SNOW AMOUNTS IN THE NORTHEAST PART OF THE FORECAST AREA...BOTTINEAU-ROLLA-RUGBY-HARVEY LATE SATURDAY NIGHT INTO SUNDAY MORNING. OTHER THAN THAT THERE WILL BE A CHANCE OF LIGHT PRECIPITATION MONDAY/MONDAY NIGHT. REGARDING THIS SATURDAY NIGHT/SUNDAY CLIPPER EVENT...TODAY`S MODELS ARE INDICATING WARM AIR ADVECTION AHEAD OF THE SURFACE CLIPPER - ENOUGH SUCH THAT PRECIPITATION SATURDAY EVENING AND INTO VERY EARLY SUNDAY MORNING WOULD BE AHEAD AND EAST OF THE SURFACE LOW AND IN THE FORM OF RAIN. RAIN WOULD NOT BE CHANGING TO SNOW UNTIL ROUGHLY 3 AM IN THE TURTLE MOUNTAINS...THOUGH FARTHER WEST THE CHANGE TO SNOW MAY OCCUR AROUND MIDNIGHT SATURDAY NIGHT. A GOOD AMOUNT OF THE PRECIPITATION ASSOCIATED WITH THIS SYSTEM IS PROGGED TO BEGIN LATE AFTERNOON/EARLY EVENING...WITH THE BEST LIFT AND MORE INTENSE PRECIPITATION OCCURRING BEFORE MIDNIGHT. THE SURFACE LOW IS PROGGED TO MOVE SOUTH FROM SASKATCHEWAN AND CROSS THE NORTH DAKOTA BORDER BETWEEN 10 PM AND MIDNIGHT. THUS THE BULK OF THE ASSOCIATED PRECIPITATION SHOULD BE IN THE FORM OF RAIN. REGARDING SNOW AMOUNTS...THE LATEST EXPECTATION IS THAT THE TURTLE MOUNTAINS MAY RECEIVE UP TO 2 INCHES OF SNOW FROM SATURDAY NIGHT THROUGH SUNDAY...WITH HALF AN INCH TO AN INCH IN THE SURROUNDING AREAS FROM BOTTINEAU TO NORTHERN MCHENRY TO PIERCE COUNTIES. LESSER AMOUNTS EXPECTED ACROSS NORTHWESTERN NORTH DAKOTA TO THE NORTHERN JAMES RIVER VALLEY. WINDY AS WELL SATURDAY NIGHT AND SUNDAY AS THE CLIPPER LOW MOVES FROM THE NORTH CENTRAL TO SOUTHEASTERN NORTH DAKOTA. NORTHWEST WINDS OF 20 TO 30 MPH EARLY SUNDAY MORNING IN THE WEST...AND DAYTIME SUNDAY OVER WESTERN AND CENTRAL NORTH DAKOTA. A NEXT WEAKER WAVE IS THROUGH ON MONDAY / TUESDAY...FOLLOWED BY THE BUILDING H5 RIDGE WITH DRIER AND MORE SEASONAL TEMPERATURES. THE REST OF THE LONG TERM WILL SEE HIGHS IN THE 30S AND 40S OVER CENTRAL NORTH DAKOTA...AND 40S TO LOWER 50S OVER WESTERN NORTH DAKOTA. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 524 PM CDT FRI OCT 18 2013 LOW VFR TO MVFR CIGS NEXT 24HR AS ISOLATED TO SCATTERED RAIN AND SNOW SHOWERS MOVE FROM NORTH TO SOUTH. FOR THURSDAY EVENING...IT APPEARS KBIS/KJMS WILL HAVE THE HIGHEST PROBABILITY FOR SHOWERS WITH A VCSH IN THE REST OF THE TERMINALS. CIGS WILL LIFT TO VFR SATURDAY AFTERNOON AS A WARM FRONT MOVES THROUGH CENTRAL NORTH DAKOTA. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...RP KINNEY LONG TERM...JV AVIATION...KS
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
345 PM CDT FRI OCT 18 2013 .DISCUSSION... WIDESPREAD SHOWERS WITH ISOLATED THUNDER HAVE BEEN GOING ON OVER THE WATERS TODAY. ISOLATED TO SCATTERED COVERAGE HAS BEEN OBSERVED ALONG THE COASTAL COUNTIES. THIS IS ALL IN THANKS TO WIDESPREAD ISENTROPIC LIFT. THE 850MB MOISTURE AXIS HAS CONTINUED TO PUSH TO THE NORTHEAST FROM THE SOUTHWEST THIS AFTERNOON ALLOWING FOR MORE OF THE RAIN TO REACH THE GROUND THIS AFTERNOON. INSTABILITY REMAINS LIMITED THOUGH SO THUNDER LOOKS TO BE ISOLATED. A SOUNDING FROM KCLL AT 15Z SHOWS A SATURATED LAYER JUST ABOVE 800MB TO ABOUT 600MB. INSTABILITY IS LIMITED. LOW LEVEL DRY AIR SHOULD START TO ERODE AS THE THE WARM FRONT LIFTS NORTHWARDS. COMPARING A 250MB HAND ANALYSIS FROM THIS MORNING THE ECMWF SEEMS TO HAVE THE POSITION OF THE JET BEST. BOTH MODELS ARE CLOSE THOUGH. EITHER WAY SOUTHEAST TEXAS IS IN THE RRQ OR DIVERGENT REGION OF THE JET STREAK. THIS IN COMBINATION WITH A COLD FRONT WILL HELP PROVIDE THE LIFTING MECHANISMS FOR RAIN THROUGH THE EVENING HOURS. THE TEXAS TECH WRF HAS PRECIP LIMITED WITH THE FRONT WHILE THE HRRR HAS WIDESPREAD RAIN AHEAD OF THE FRONT. BOTH MODELS SEEMED TO HAVE INITIALIZED WELL. GIVEN SPOTTY COVERAGE NOW HAVE LEANED TOWARDS THE WETTER SOLUTION. WAS A BIT HESITANT THOUGH GIVEN WIDESPREAD CONVECTION ONGOING OVER WATERS. THIS COULD HINDER THE DEVELOPMENT INLAND. BEHIND THIS FRONT BOTH ECMWF AND GFS POSITION THE SURFACE HIGH PRESSURE OVER CENTRAL TEXAS SUNDAY MORNING. THIS WILL ALLOW TEMPERATURES TO DROP INTO THE 40S FOR MOST INLAND LOCATIONS. THIS FRONT WILL AGAIN BE SHORT LIVED THOUGH AS IT BEGINS TO PULL NORTHWARDS ON MONDAY. A SIMILAR SET UP TO THIS EVENING WILL AGAIN BE ON TAP MONDAY NIGHT INTO TUESDAY. THE GFS AND ECMWF APPEAR TO BE IN AGREEMENT WITH THE BEST UPPER LEVEL DIVERGENCE TO BE OFF THE COAST AND THEN MOVING INTO LA. BEHIND THIS FRONT A SURFACE HIGH PRESSURE WILL MOVE DOWN ALLOWING FOR PLEASANT CONDITIONS BEHIND THE FRONT. THE GFS AND ECMWF HAVE THE BULK OF THE HIGH PRESSURE MOVING OFF TOWARDS THE EAST IN ASSOCIATION WITH THE LONG WAVE TROUGH. THIS SHOULD STILL ALLOW FOR NICE CONDITIONS TO CONTINUE THOUGH THE REMAINDER OF THE WORK WEEK. 23 && .MARINE... DIFFICULT MARINE FORECAST THIS AFTERNOON...AND MARINERS ARE URGED TO CLOSELY MONITOR THE WEATHER AND WEATHER FORECASTS OVER THE NEXT SEVERAL DAYS FOR POSSIBLE CHANGES. WINDS THAT HAVE BEEN AT CAUTION LEVELS OFF THE COAST FOR SEVERAL HOURS NOW SHOULD COME DOWN LATER THIS AFTERNOON AND THIS EVENING AS THE NEXT COLD FRONT APPROACHES THE AREA. AFTER THE FRONTAL PASSAGE LATE TONIGHT THROUGH EARLY TOMORROW MORNING...WINDS ARE EXPECTED TO STRENGTHEN AGAIN TO CAUTION LEVELS FOR THE BAYS AND CLOSE TO ADVISORY LEVELS OFF THE COAST. INSTEAD OF CARRYING FLAGS THIS AFTERNOON THEN LOWERING THEM THIS EVENING THEN RAISING THEM AGAIN BEFORE SUNRISE...DECIDED TO JUST KEEP FLAGS UP THROUGH TOMORROW AS THIS STORM SYSTEM AND ASSOCIATED SHOWERS AND THUNDERSTORMS MOVE ON THROUGH. WINDS AND SEAS SHOULD COME DOWN LATE SATURDAY AFTERNOON AND ON INTO SATURDAY NIGHT...THEN PICK UP AGAIN ON MONDAY NIGHT AND TUESDAY AFTER THE PASSAGE OF THE NEXT STORM SYSTEM AND COLD FRONT. ELEVATED WINDS AND SEAS EXPECTED TO THEN PERSIST INTO THE MIDDLE OF THE WEEK SHOULD COME DOWN DURING THE SECOND HALF OF THE WEEK AS HIGH PRESSURE BUILDS INTO THE AREA AND THE GRADIENT RELAXES. 42 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 53 69 47 75 58 / 60 20 10 0 20 HOUSTON (IAH) 59 73 50 78 60 / 60 30 10 0 20 GALVESTON (GLS) 68 75 62 76 68 / 70 50 10 10 50 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...SMALL CRAFT SHOULD EXERCISE CAUTION FROM LATE TONIGHT THROUGH SATURDAY AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY... MATAGORDA BAY. SMALL CRAFT ADVISORY FROM 4 AM TO 6 PM CDT SATURDAY FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM. SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH LATE TONIGHT FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM. && $$ DISCUSSION...23 AVIATION/MARINE...42