Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 12/01/14


AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
937 PM CST SUN NOV 30 2014 .UPDATE... NO APPRECIABLE CHANGES WILL BE FORTH COMING THIS EVENING. LATEST SURFACE ANALYSIS SHOWS THE COLD FRONT HAS CLEARED NORTHWEST ARKANSAS WITH TEMPERATURES ALREADY DOWN IN THE UPPER 30S IN BENTON COUNTY. LZK 00Z SOUNDING SHOWS CONSIDERABLE LAYER OF DRY AIR JUST OFF THE DECK BUT KSGF RAOB IS MOISTENING UP. WOULD NOT BE SURPRISED TO SEE AS LITTLE SLEET MIXED IN BASED ON THIS SOUNDING. PRECIP CHANCES MAY BE DELAYED A SHORT TIME BUT HRRR AND NEW NAM DOES SHOW PRECIPITATION STARTING OVER THE NEXT FEW HOURS. TIMING AND PLACEMENT OF THE WINTER WEATHER ADVISORY STILL LOOK GOOD AND AMOUNTS OF ACTUAL ICE STILL LOOK TO BE UNDER A TENTH OF AN INCH. PRIMARY CONCERN WILL REMAIN ELEVATED SURFACES. && .PREV DISCUSSION... /ISSUED 551 PM CST SUN NOV 30 2014/ AVIATION... A COLD FRONT HAS ENTERED FAR NORTHWEST ARKANSAS EARLY THIS EVENING. WINDS WILL BECOME NORTH ON THE BACK SIDE OF THE FRONT. THE FRONT WILL BE SLOW TO MOVE THROUGH THE STATE BUT WILL BRING LIGHT RAIN TO MOST PLACES AND DRIZZLE...FREEZING DRIZZLE AND SLEET TO THE NORTH. EXPECT LIGHT DRIZZLE AND SLEET TO BEGIN LATE THIS EVENING IN THE NORTH. THEN IT WILL SWITCH TO FREEZING DRIZZLE AND LAST INTO EARLY AFTERNOON. VFR CONDITIONS WILL BECOME IFR. PREV DISCUSSION... /ISSUED 248 PM CST SUN NOV 30 2014/ SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT THE MAIN CONCERN FOR THE SHORT TERM IS THE IMPENDING WINTER WEATHER SLATED TO AFFECT THE NORTHERN PARTS OF ARKANSAS TONIGHT. AS SUCH THE DISCUSSION WILL FOCUS PRIMARILY ON THAT. REGIONAL SURFACE ANALYSIS SHOWS A STARK COLD FRONT SITUATED FROM SOUTH OF OKLAHOMA CITY...THROUGH SOUTH OF TULSA...AND THROUGH ROUGHLY THE SPRINGFIELD MISSOURI AREA THIS AFTERNOON. THIS FRONT WILL CREEP SOUTHWARD THROUGH ARKANSAS OVER THE NEXT 24 HOURS OR SO...FINALLY PUSHING SOUTH OF THE STATE BY MONDAY EVENING. FROPA SHOULD BE OCCUR JUST BEFORE MIDNIGHT TONIGHT AT HARRISON...AROUND DAYBREAK AT PLACES LIKE LITTLE ROCK...MOUNT IDA...AND CLARENDON...AND FINALLY BY EARLY AFTERNOON IN THE FAR SOUTH. AHEAD OF THE FRONT UNSEASONABLY WARM AND HUMID CONDITIONS HAVE BEEN SEEN THIS WEEKEND...WITH HIGHS TODAY RISING INTO THE UPPER 70S IN PLACES. CONVERSELY...HIGHS FOR MANY PLACES TOMORROW WILL BE DURING THE EARLY MORNING HOURS...WITH TEMPERATURES FALLING INTO THE MID 30S BEHIND THE FRONT DURING THE DAY MONDAY. MEANWHILE...A WEAK DISTURBANCE WILL BEGIN TO APPROACH FROM THE WEST LATER TODAY AND EVENTUALLY MOVE EAST OF THE STATE BY MON EVENING...RESULTING IN LIGHT PRECIP ACROSS THE FORECAST AREA FROM LATE TONIGHT THROUGH THE DAY MONDAY. INITIALLY THIS WILL BEGIN AS RAIN...BUT AS THE AFOREMENTIONED COLD FRONT BEGINS TO PUSH INTO ARKANSAS FROM THE NORTH...THE POST FRONTAL AIR SHOULD BE SUFFICIENTLY COLD AND DEEP ENOUGH TO CHANGE PRECIPITATION TO MAINLY FREEZING RAIN. ONE CAVEAT WOULD BE THAT THERE ARE SOME CONVECTIVE ELEMENTS NOTED IN MODEL OUTPUT SO I WOULD NOT BE SURPRISED TO SEE SOME SLEET DEVELOP IN PLACES...MAINLY IN NORTH CENTRAL AND NORTHEAST ARKANSAS TOMORROW MORNING. HOWEVER MUCH OF THE MOISTURE WILL REMAIN BELOW THE DENDRITIC GROWTH ZONE SO THE PREDOMINANT PRECIPITATION TYPE SHOULD BE FREEZING RAIN. PRECIPITATION AMOUNTS SHOULD NOT BE TOO HIGH. THE...RELATIVELY SPEAKING...HEAVIEST PERIOD OF PRECIPITATION WILL BE AS THE UPPER DISTURBANCE MOVES THROUGH MID MORNING INTO THE AFTERNOON HOURS TOMORROW...AND EVEN THEN MODELS ARE SHOWING LESS THAN A QUARTER OF AN INCH OF QPF IN THE HEAVIEST SPOTS. ONCE THE DISTURBANCE PASSES THERE SHOULD STILL BE ENOUGH MOISTURE LEFTOVER FOR SOME LINGERING FREEZING DRIZZLE THROUGH LATE MON EVENING. PRECIPITATION SHOULD BEGIN WINDING DOWN...AND TEMPERATURES STILL WARM ENOUGH...TO CONFINE ANY WINTRY PRECIPITATION TO MAINLY THE NORTHERN TWO ROWS OF COUNTIES. GIVEN THE CURRENT UNSEASONABLY WARM AIR TEMPERATURES AND THE RESULT THIS HAS HAD ON GROUND TEMPS...DO NOT EXPECT THERE TO BE AN IMMEDIATE ACCRUAL OF ICE ON ANY SURFACE ONCE THE FRONT PASSES AND TEMPERATURES FALL BELOW THE FREEZING MARK IN ANY GIVEN LOCATION. HOWEVER WITH TEMPS REMAINING BELOW FREEZING...AREAS IN NRN ARKANSAS WILL UNDOUBTEDLY BEGIN TO SEE ACCUMULATING ICE BEFORE MIDDAY MON. THIS IS MOST LIKELY TO OCCUR ON ELEVATED SURFACES LIKE TREES AND POWERLINES...BUT BY MON EVENING ROADWAYS WILL LIKELY BE COLD ENOUGH SUCH THAT ANY FURTHER FREEZING DRIZZLE OR LIGHT FREEZING RAIN COULD CAUSE SOME SLICK SPOTS AND HAZARDOUS TRAVEL. FOR THESE REASONS...HAVE HOISTED UP A WINTER WEATHER ADVISORY IN THE NRN TWO ROWS OF COUNTIES TO ACCOUNT FOR THIS. FEEL THAT...DESPITE LACK OF SIGNIFICANT ICE ACCUMULATION...THERE WILL STILL BE ENOUGH TRAVEL IMPACTS TO WARRANT AN ADVISORY. ELSEWHERE...CENTRAL AND SOUTHERN ARKANSAS SHOULD NOT SEE COLD ENOUGH TEMPERATURES WHILE PRECIP IS ONGOING TO WARRANT ANY CONCERNS AT THIS TIME. OTHERWISE...COOLER THAN NORMAL TEMPERATURES WILL AFFECT THE STATE THROUGH TUESDAY. BUT A WARMUP IS EXPECTED AS WE HEAD INTO WED. THE FRONT MOVING THROUGH TOMORROW WILL LIFT BACK NORTH INTO ARKANSAS ON WED...AND A SIMILAR SITUATION IN TERMS OF WIDESPREAD LIGHT PRECIPITATION SHOULD DEVELOP WED NIGHT. THIS TIME ONLY RAIN IS EXPECTED THOUGH AS THERE WILL BE NO ARCTIC BOUNDARY PUSHING INTO THE REGION FROM THE NORTH TO CHANGE PRECIPITATION OVER. LONG TERM...THURSDAY THROUGH SUNDAY AN UNSETTLED WEATHER PATTERN WILL BE OVER THE CENTRAL U.S. AND KEEP RAIN CHANCES IN THE FORECAST EVERY DAY. THE NEARLY ZONAL UPPER PATTER WILL KEEP TEMPS WELL ABOVE FREEZING IN NORMAL VALUES...AND ALLOW SHORT WAVE ENERGY TO MOVE THROUGH THE PATTERN AND AFFECT AR. THURSDAY WILL START WITH A WEAK FRONTAL BOUNDARY NEARLY STATIONARY OVER AR...WITH MAINLY A SHOWER POTENTIAL FOR THURSDAY AND FRIDAY. A BIT MORE SHORT WAVE ENERGY IS SEEN IN THE MODELS FRIDAY AND OVER THE WEEKEND...SO A BIT BETTER RAIN CHANCES WITH SLIGHT CHANCES OF THUNDER ARE IN THE FORECAST OVER THE WEEKEND. && .PRELIMINARY POINT TEMPS/POPS... BATESVILLE AR 36 38 29 44 / 60 70 10 10 CAMDEN AR 60 61 35 49 / 20 70 20 10 HARRISON AR 28 30 26 44 / 60 40 10 10 HOT SPRINGS AR 51 54 32 47 / 50 70 20 10 LITTLE ROCK AR 49 53 32 46 / 50 70 20 10 MONTICELLO AR 60 60 36 49 / 20 70 30 10 MOUNT IDA AR 47 50 31 47 / 50 60 20 10 MOUNTAIN HOME AR 31 32 27 44 / 60 40 10 10 NEWPORT AR 38 41 30 44 / 60 70 20 10 PINE BLUFF AR 56 57 34 47 / 30 70 20 10 RUSSELLVILLE AR 42 45 30 46 / 60 60 10 10 SEARCY AR 43 46 30 44 / 60 70 20 10 STUTTGART AR 47 51 33 46 / 40 70 20 10 && .LZK WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM CST MONDAY FOR BAXTER- BOONE-FULTON-IZARD-MARION-NEWTON-SEARCY-SHARP-STONE. && $$ 56
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
935 AM EST SAT NOV 29 2014 .SYNOPSIS... HIGH PRESSURE CENTERED ALONG THE MIDDLE ATLANTIC COAST EARLY THIS MORNING WILL DRIFT TO THE EAST AND OUT TO SEA TODAY. A WARM FRONT APPROACHING FROM THE SOUTHWEST IS FORECAST TO ARRIVE TONIGHT, FOLLOWED BY A COLD FRONT FROM THE NORTHWEST ON MONDAY. HIGH PRESSURE IS EXPECTED TO BUILD INTO OUR REGION FROM THE WEST FOR TUESDAY WITH ANOTHER COLD FRONT ANTICIPATED TO ARRIVE LATE ON WEDNESDAY. HIGH PRESSURE IS FORECAST TO BUILD ACROSS NEW YORK STATE, NEW ENGLAND AND SOUTHEASTERN CANADA DURING THURSDAY AND FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... HIGH PRESSURE AT THE SURFACE IS OVER OUR AREA TO START THE DAY, HOWEVER THIS WILL THEN SHIFT OFFSHORE. THE FLOW ALOFT IS MAINLY TURNING ZONAL TODAY, ALTHOUGH SOME BACKING TO THE SOUTHWEST IS FORECAST TO OCCUR BY LATE IN THE DAY. AS THE FLOW BACKS AND LOW PRESSURE BEGINS TO ORGANIZE ACROSS THE UPPER MIDWEST, A RETURN FLOW WILL BECOME BETTER ESTABLISHED BETWEEN IT AND HIGH PRESSURE SHIFTING TO OUR EAST. THERE IS DECENT WAA FORECAST TO DEVELOP THROUGH THE DAY, AND THIS WILL HELP ORGANIZE A WARM FRONT TO OUR SOUTHWEST WHICH THEN LIFT NORTHEASTWARD. THE PRESENCE OF THE WAA DEVELOPING /STRONGER ALOFT/ WILL HELP INCREASE THE ISENTROPIC LIFT. THIS MAY ASSIST IN GENERATING SOME FLURRIES OR LIGHT SNOW. THE FORECAST SOUNDINGS LOOK FAIRLY DRY BELOW THE CLOUD BEARING LEVEL, WHICH MAY RESULT IN VIRGA/SNIRGA. THERE MAY BE ENOUGH MID LEVEL MOISTURE THOUGH IN CONJUNCTION WITH THE ISENTROPIC LIFT TO PRODUCE SOME LIGHT SNOW ACROSS PARTS OF THE AREA ESPECIALLY THROUGH MIDDAY. THE GREATEST CHC /STILL LOW POPS THOUGH/ APPEAR TO BE MAINLY ACROSS PORTIONS OF EASTERN PENNSYLVANIA TO NORTHWESTERN NEW JERSEY. THEREFORE WE WILL CONTINUE TO CARRY SOME 20-30 POPS FOR A TIME. SOME SNOW IS BEING REPORTED TO OUR WEST ACROSS CENTRAL PENNSYLVANIA AND EVEN ACROSS PORTIONS OF WESTERN MARYLAND, HOWEVER EVEN THE HRRR KEEPS THIS WEST OF OUR CWA. GIVEN THE LOW POPS, NO SNOW ACCUMULATIONS ARE INCLUDED ALTHOUGH A LOCALIZED LIGHT COATING CANNOT BE RULED OUT. OTHERWISE, WE SHOULD HAVE A DECENT AMOUNT OF MID TO HIGH LEVEL CLOUDS AROUND THE AREA TODAY DUE TO THE WAA AND INCOMING WARM FRONT. WE ARE ANTICIPATING TEMPERATURES TO BE A BIT HIGHER THAN YESTERDAY, BUT SINCE MIXING MAY NOT BE ALL THAT EFFICIENT WE WENT CLOSE TO A NAM/GFS MOS BLEND. THE LAMP/LAV GUIDANCE WAS USED EARLY THIS MORNING TO HELP ASSIST IN TEMPERATURE TRENDS GIVEN SOME VARIABILITY WITH RADIATIONAL COOLING LOCATIONS AND SOME CLOUD COVER AT TIMES FOR OTHERS. MINOR ADJUSTMENTS WERE MADE TO TEMPERATURES TO BETTER REFLECT THE CURRENT CONDITIONS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/... HIGH PRESSURE TO OUR EAST AND LOW PRESSURE TRACKING UP TOWARDS HUDSON BAY IN CANADA WILL PROMOTE A CONTINUATION OF A RETURN FLOW. THE PRESSURE GRADIENT WILL ALSO TIGHTEN BETWEEN THESE TWO SYSTEMS, AND THE MODEL GUIDANCE INCREASES THE 925 MB WINDS TO AROUND 30 KNOTS OVERNIGHT. THIS WILL HELP ASSIST WITH THE CONTINUATION OF WAA AS A SOUTH TO SOUTHWEST FLOW IS MAINTAINED. A WARM FRONT WILL BE DRIVEN NORTH ACROSS OUR AREA AS A RESULT AND OVERALL THE LIFT ASSOCIATED WITH IT AND THE WAA APPEAR TO BE WEAK. THE MOISTURE WILL GRADUALLY INCREASE AND THEREFORE A FAIR AMOUNT OF CLOUDS SHOULD BE AROUND ESPECIALLY IN ADVANCE OF THE WARM FRONT ITSELF. THE FORECAST SOUNDINGS INDICATE A MOISTENING UP OF THE LOW LEVELS. THIS IS BENEATH SOME DRIER AIR AND WITH LITTLE IN THE WAY OF FORCING, PERHAPS SOME DRIZZLE COULD DEVELOP MAINLY ACROSS NORTHEASTERN PENNSYLVANIA AND NORTHWESTERN NEW JERSEY. THE DEPTH OF THE MOISTENING LAYER THOUGH MAY NOT BE CONDUCIVE ENOUGH SINCE THE FLOW IS MORE SOUTHERLY AS OPPOSED TO ONSHORE. GIVEN SUCH A LOW CHC AND OUR CONFIDENCE BEING LOW, WE DID NOT INCLUDE A MENTION IN THE FORECAST ATTM. IF SOME DRIZZLE WERE TO OCCUR, IT IS WORTH MENTIONING THAT SOME FREEZING DRIZZLE COULD OCCUR UP NORTH GIVEN AIR TEMPERATURES FORECAST TO BE NEAR FREEZING DESPITE THE WAA. THERE MAY NOT BE MUCH WIND AT THE SURFACE GIVEN AN INVERSION DEVELOPING. AS FOR LOW TEMPERATURES, WE GENERALLY SIDED WITH AN EVEN BLEND OF THE NAM/GFS MOS. TEMPERATURES MAY ACTUALLY HOLD STEADY OR RISE A LITTLE ESPECIALLY IF THE CLOUD COVER IS NEARLY SOLID. && .LONG TERM /SUNDAY THROUGH FRIDAY/... THE MID LEVEL PATTERN IS EXPECTED TO BE SOMEWHAT ZONAL ACROSS THE NATION FOR MUCH OF THE NEW WEEK. AS A RESULT, WE ARE ANTICIPATING QUICK MOVING WEATHER SYSTEMS AND TEMPERATURES SHOULD OSCILLATE AROUND NORMAL. A WARM FRONT IS EXPECTED TO LIFT TO OUR NORTH ON SUNDAY, LEAVING OUR REGION IN A RELATIVELY MILD SOUTHWEST FLOW FOR SUNDAY INTO SUNDAY NIGHT. CLOUDS ARE EXPECTED TO LINGER OVER OUR NORTHWESTERN COUNTIES DURING THAT PERIOD. A MID LEVEL SHORT WAVE TROUGH IS ANTICIPATED TO MOVE ACROSS ONTARIO AND THE GREAT LAKES ON MONDAY BEFORE PASSING ACROSS SOUTHERN QUEBEC AND THE NORTHEASTERN STATES ON MONDAY NIGHT. THE SHORT WAVE IS FORECAST TO PUSH A COLD FRONT THROUGH OUR REGION ON MONDAY AFTERNOON AND MONDAY EVENING. CLOUDS WILL ACCOMPANY THE BOUNDARY AND THERE IS A LOW CHANCE OF LIGHT RAIN SHOWERS. SURFACE HIGH PRESSURE IS EXPECTED TO MOVE FROM THE GREAT LAKES ON MONDAY NIGHT TO THE SAINT LAWRENCE RIVER VALLEY ON TUESDAY. THE HIGH WILL PUSH DRY AIR DOWN INTO OUR REGION. HOWEVER, CLOUDS AND SOME LIGHT RAIN MAY LINGER, ESPECIALLY ACROSS OUR FAR SOUTHERN COUNTIES. AS THE HIGH MOVES FARTHER TO THE EAST, THE SURFACE FLOW IN OUR REGION IS FORECAST TO VEER FROM THE EAST TO THE SOUTH ON TUESDAY NIGHT. THE FLOW OFF THE OCEAN SHOULD RESULT IN AN INCREASE IN MOISTURE ALONG WITH LOWERING CLOUDS AND AN INCREASING CHANCE OF PRECIPITATION INTO WEDNESDAY. ANOTHER COLD FRONT FROM THE NORTHWEST IS ANTICIPATED TO ARRIVE LATE ON WEDNESDAY. DRY AIR IS EXPECTED TO FOLLOW FOR THURSDAY. STRONG HIGH PRESSURE IS FORECAST TO FOLLOW A SIMILAR TRACK TO THE EARLY WEEK AREA OF HIGH PRESSURE. AS THE CENTER OF THE HIGH MOVES FROM THE SAINT LAWRENCE RIVER VALLEY TO THE MARITIME PROVINCES ON FRIDAY, THE SURFACE FLOW IN OUR REGION SHOULD AGAIN VEER FROM THE EAST TO THE SOUTH RESULTING IN A MOIST ONSHORE FLOW. THERE COULD BE CLOUDS AND SOME LIGHT RAIN ON FRIDAY. && .AVIATION /15Z SATURDAY THROUGH WEDNESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. TODAY...VFR WITH CEILINGS AT OR ABOVE 5000 FEET. SOME FLURRIES OR A LITTLE LIGHT SNOW IS POSSIBLE ESPECIALLY NORTH AND WEST OF KPHL. IF THIS WERE TO REACH THE GROUND, THE LOCAL VISIBILITY MAY BRIEFLY LOWER TO MVFR. THE CHANCE THOUGH IS TO LOW AT THIS TIME TO INCLUDE IN THE TAFS. A LIGHT AND VARIABLE OR CALM WIND, BECOMING SOUTHERLY UP TO 10 KNOTS DURING THE COURSE OF THE DAY. TONIGHT...VFR OVERALL, WITH CEILINGS MAINLY IN THE 5000 TO 15000 FEET RANGE. SOUTH-SOUTHWEST WINDS LESS THAN 10 KNOTS. OUTLOOK... SUNDAY THROUGH TUESDAY...MAINLY VFR. TUESDAY NIGHT AND WEDNESDAY...MVFR AND IFR CONDITIONS ARE POSSIBLE ALONG WITH A CHANCE OF LIGHT RAIN. SOME LIGHT SNOW MAY FALL ON TUESDAY NIGHT, ESPECIALLY AROUND KRDG AND KABE. && .MARINE... HIGH PRESSURE WILL SHIFT TO OUR EAST TODAY ALLOWING FOR A SOUTHERLY FLOW TO DEVELOP. A WARM FRONT WILL ARRIVE TONIGHT, AND A WAA PATTERN WILL OCCUR TODAY THROUGH TONIGHT. AS THE WAA STRENGTHENS, A LOW-LEVEL JET /925 MB/ ON THE ORDER OF 30-35 KNOTS IS FORECAST TO MOVE ACROSS THE AREA LATER TONIGHT. THE FORECAST SOUNDINGS DO SHOW THE POTENTIAL FOR GUSTS TO AROUND 25 KNOTS TO OCCUR FOR A TIME TONIGHT. WHILE WE WILL BE WITHIN A WAA PATTERN, IT APPEARS THAT SMALL CRAFT ADVISORY CRITERIA WILL BE MET ON THE OCEAN ZONES. IN ADDITION, THE INCREASING SOUTHERLY FLOW WILL BUILD THE SEAS THROUGH TONIGHT. AFTER COLLABORATION WITH WFO`S OKX AND AKQ, WE ISSUED A SMALL CRAFT ADVISORY STARTING AT 23Z TONIGHT FOR JUST THE OCEAN ZONES. OUTLOOK... SUNDAY...A SMALL CRAFT ADVISORY IS IN EFFECT ON OUR OCEAN WATERS FOR A SOUTHWEST WIND GUSTING TO 25 OR 30 KNOTS AND WAVE HEIGHTS BUILDING NEAR 5 FEET. WIND SPEEDS SHOULD BE SLIGHTLY LOWER ON DELAWARE BAY AND NO ADVISORY IS IN EFFECT THERE. SUNDAY NIGHT...WINDS AND SEAS ARE FORECAST TO DECREASE SLOWLY. HOWEVER, THE SMALL CRAFT ADVISORY MAY EVENTUALLY NEED TO BE EXTENDED. MONDAY THROUGH TUESDAY...ANOTHER SMALL CRAFT ADVISORY MAY BE NEEDED AS A COLD FRONT PUSHES THROUGH OUR REGION. TUESDAY NIGHT AND WEDNESDAY...NO MARINE HEADLINES ARE ANTICIPATED. && .EQUIPMENT... THE WSR-88D LOCATED AT FORT DIX, NEW JERSEY (KDIX) REMAINS OUT OF SERVICE. WE ARE WAITING ON REPLACEMENT PARTS AND WE HOPE TO HAVE THE RADAR REPAIRED BY THE END OF THE DAY. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 PM EST SUNDAY FOR ANZ450>455. && $$ SYNOPSIS...IOVINO NEAR TERM...GORSE/MEOLA SHORT TERM...GORSE LONG TERM...IOVINO AVIATION...GORSE/IOVINO MARINE...GORSE/IOVINO EQUIPMENT...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
424 AM EST SAT NOV 29 2014 .SYNOPSIS... HIGH PRESSURE CENTERED ALONG THE MIDDLE ATLANTIC COAST EARLY THIS MORNING WILL DRIFT TO THE EAST AND OUT TO SEA TODAY. A WARM FRONT APPROACHING FROM THE SOUTHWEST IS FORECAST TO ARRIVE TONIGHT, FOLLOWED BY A COLD FRONT FROM THE NORTHWEST ON MONDAY. HIGH PRESSURE IS EXPECTED TO BUILD INTO OUR REGION FROM THE WEST FOR TUESDAY WITH ANOTHER COLD FRONT ANTICIPATED TO ARRIVE LATE ON WEDNESDAY. HIGH PRESSURE IS FORECAST TO BUILD ACROSS NEW YORK STATE, NEW ENGLAND AND SOUTHEASTERN CANADA DURING THURSDAY AND FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... HIGH PRESSURE AT THE SURFACE IS OVER OUR AREA TO START THE DAY, HOWEVER THIS WILL THEN SHIFT OFFSHORE. THE FLOW ALOFT IS MAINLY TURNING ZONAL TODAY, ALTHOUGH SOME BACKING TO THE SOUTHWEST IS FORECAST TO OCCUR BY LATE IN THE DAY. AS THE FLOW BACKS AND LOW PRESSURE BEGINS TO ORGANIZE ACROSS THE UPPER MIDWEST, A RETURN FLOW WILL BECOME BETTER ESTABLISHED BETWEEN IT AND HIGH PRESSURE SHIFTING TO OUR EAST. THERE IS DECENT WAA FORECAST TO DEVELOP THROUGH THE DAY, AND THIS WILL HELP ORGANIZE A WARM FRONT TO OUR SOUTHWEST WHICH THEN LIFT NORTHEASTWARD. THE PRESENCE OF THE WAA DEVELOPING /STRONGER ALOFT/ WILL HELP INCREASE THE ISENTROPIC LIFT. THIS MAY ASSIST IN GENERATING SOME FLURRIES OR LIGHT SNOW. THE FORECAST SOUNDINGS LOOK FAIRLY DRY BELOW THE CLOUD BEARING LEVEL, WHICH MAY RESULT IN VIRGA/SNIRGA. THERE MAY BE ENOUGH MID LEVEL MOISTURE THOUGH IN CONJUNCTION WITH THE ISENTROPIC LIFT TO PRODUCE SOME LIGHT SNOW ACROSS PARTS OF THE AREA ESPECIALLY THROUGH MIDDAY. THE GREATEST CHC /STILL LOW POPS THOUGH/ APPEAR TO BE MAINLY ACROSS PORTIONS OF EASTERN PENNSYLVANIA TO NORTHWESTERN NEW JERSEY. THEREFORE WE WILL CONTINUE TO CARRY SOME 20-30 POPS FOR A TIME. SOME SNOW IS BEING REPORTED TO OUR WEST ACROSS CENTRAL PENNSYLVANIA AND EVEN ACROSS PORTIONS OF WESTERN MARYLAND, HOWEVER EVEN THE HRRR KEEPS THIS WEST OF OUR CWA. GIVEN THE LOW POPS, NO SNOW ACCUMULATIONS ARE INCLUDED ALTHOUGH A LOCALIZED LIGHT COATING CANNOT BE RULED OUT. OTHERWISE, WE SHOULD HAVE A DECENT AMOUNT OF MID TO HIGH LEVEL CLOUDS AROUND THE AREA TODAY DUE TO THE WAA AND INCOMING WARM FRONT. WE ARE ANTICIPATING TEMPERATURES TO BE A BIT HIGHER THAN YESTERDAY, BUT SINCE MIXING MAY NOT BE ALL THAT EFFICIENT WE WENT CLOSE TO A NAM/GFS MOS BLEND. THE LAMP/LAV GUIDANCE WAS USED EARLY THIS MORNING TO HELP ASSIST IN TEMPERATURE TRENDS GIVEN SOME VARIABILITY WITH RADIATIONAL COOLING LOCATIONS AND SOME CLOUD COVER AT TIMES FOR OTHERS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/... HIGH PRESSURE TO OUR EAST AND LOW PRESSURE TRACKING UP TOWARDS HUDSON BAY IN CANADA WILL PROMOTE A CONTINUATION OF A RETURN FLOW. THE PRESSURE GRADIENT WILL ALSO TIGHTEN BETWEEN THESE TWO SYSTEMS, AND THE MODEL GUIDANCE INCREASES THE 925 MB WINDS TO AROUND 30 KNOTS OVERNIGHT. THIS WILL HELP ASSIST WITH THE CONTINUATION OF WAA AS A SOUTH TO SOUTHWEST FLOW IS MAINTAINED. A WARM FRONT WILL BE DRIVEN NORTH ACROSS OUR AREA AS A RESULT AND OVERALL THE LIFT ASSOCIATED WITH IT AND THE WAA APPEAR TO BE WEAK. THE MOISTURE WILL GRADUALLY INCREASE AND THEREFORE A FAIR AMOUNT OF CLOUDS SHOULD BE AROUND ESPECIALLY IN ADVANCE OF THE WARM FRONT ITSELF. THE FORECAST SOUNDINGS INDICATE A MOISTENING UP OF THE LOW LEVELS. THIS IS BENEATH SOME DRIER AIR AND WITH LITTLE IN THE WAY OF FORCING, PERHAPS SOME DRIZZLE COULD DEVELOP MAINLY ACROSS NORTHEASTERN PENNSYLVANIA AND NORTHWESTERN NEW JERSEY. THE DEPTH OF THE MOISTENING LAYER THOUGH MAY NOT BE CONDUCIVE ENOUGH SINCE THE FLOW IS MORE SOUTHERLY AS OPPOSED TO ONSHORE. GIVEN SUCH A LOW CHC AND OUR CONFIDENCE BEING LOW, WE DID NOT INCLUDE A MENTION IN THE FORECAST ATTM. IF SOME DRIZZLE WERE TO OCCUR, IT IS WORTH MENTIONING THAT SOME FREEZING DRIZZLE COULD OCCUR UP NORTH GIVEN AIR TEMPERATURES FORECAST TO BE NEAR FREEZING DESPITE THE WAA. THERE MAY NOT BE MUCH WIND AT THE SURFACE GIVEN AN INVERSION DEVELOPING. AS FOR LOW TEMPERATURES, WE GENERALLY SIDED WITH AN EVEN BLEND OF THE NAM/GFS MOS. TEMPERATURES MAY ACTUALLY HOLD STEADY OR RISE A LITTLE ESPECIALLY IF THE CLOUD COVER IS NEARLY SOLID. && .LONG TERM /SUNDAY THROUGH FRIDAY/... THE MID LEVEL PATTERN IS EXPECTED TO BE SOMEWHAT ZONAL ACROSS THE NATION FOR MUCH OF THE NEW WEEK. AS A RESULT, WE ARE ANTICIPATING QUICK MOVING WEATHER SYSTEMS AND TEMPERATURES SHOULD OSCILLATE AROUND NORMAL. A WARM FRONT IS EXPECTED TO LIFT TO OUR NORTH ON SUNDAY, LEAVING OUR REGION IN A RELATIVELY MILD SOUTHWEST FLOW FOR SUNDAY INTO SUNDAY NIGHT. CLOUDS ARE EXPECTED TO LINGER OVER OUR NORTHWESTERN COUNTIES DURING THAT PERIOD. A MID LEVEL SHORT WAVE TROUGH IS ANTICIPATED TO MOVE ACROSS ONTARIO AND THE GREAT LAKES ON MONDAY BEFORE PASSING ACROSS SOUTHERN QUEBEC AND THE NORTHEASTERN STATES ON MONDAY NIGHT. THE SHORT WAVE IS FORECAST TO PUSH A COLD FRONT THROUGH OUR REGION ON MONDAY AFTERNOON AND MONDAY EVENING. CLOUDS WILL ACCOMPANY THE BOUNDARY AND THERE IS A LOW CHANCE OF LIGHT RAIN SHOWERS. SURFACE HIGH PRESSURE IS EXPECTED TO MOVE FROM THE GREAT LAKES ON MONDAY NIGHT TO THE SAINT LAWRENCE RIVER VALLEY ON TUESDAY. THE HIGH WILL PUSH DRY AIR DOWN INTO OUR REGION. HOWEVER, CLOUDS AND SOME LIGHT RAIN MAY LINGER, ESPECIALLY ACROSS OUR FAR SOUTHERN COUNTIES. AS THE HIGH MOVES FARTHER TO THE EAST, THE SURFACE FLOW IN OUR REGION IS FORECAST TO VEER FROM THE EAST TO THE SOUTH ON TUESDAY NIGHT. THE FLOW OFF THE OCEAN SHOULD RESULT IN AN INCREASE IN MOISTURE ALONG WITH LOWERING CLOUDS AND AN INCREASING CHANCE OF PRECIPITATION INTO WEDNESDAY. ANOTHER COLD FRONT FROM THE NORTHWEST IS ANTICIPATED TO ARRIVE LATE ON WEDNESDAY. DRY AIR IS EXPECTED TO FOLLOW FOR THURSDAY. STRONG HIGH PRESSURE IS FORECAST TO FOLLOW A SIMILAR TRACK TO THE EARLY WEEK AREA OF HIGH PRESSURE. AS THE CENTER OF THE HIGH MOVES FROM THE SAINT LAWRENCE RIVER VALLEY TO THE MARITIME PROVINCES ON FRIDAY, THE SURFACE FLOW IN OUR REGION SHOULD AGAIN VEER FROM THE EAST TO THE SOUTH RESULTING IN A MOIST ONSHORE FLOW. THERE COULD BE CLOUDS AND SOME LIGHT RAIN ON FRIDAY. && .AVIATION /09Z SATURDAY THROUGH WEDNESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. TODAY...VFR WITH CEILINGS AT OR ABOVE 5000 FEET. SOME FLURRIES OR A LITTLE LIGHT SNOW IS POSSIBLE ESPECIALLY NORTH AND WEST OF KPHL. IF THIS WERE TO REACH THE GROUND, THE LOCAL VISIBILITY MAY BRIEFLY LOWER TO MVFR. THE CHANCE THOUGH IS TO LOW AT THIS TIME TO INCLUDE IN THE TAFS. A LIGHT AND VARIABLE OR CALM WIND, BECOMING SOUTHERLY UP TO 10 KNOTS DURING THE COURSE OF THE DAY. TONIGHT...VFR OVERALL, WITH CEILINGS MAINLY IN THE 5000 TO 15000 FEET RANGE. SOUTH-SOUTHWEST WINDS LESS THAN 10 KNOTS. OUTLOOK... SUNDAY THROUGH TUESDAY...MAINLY VFR. TUESDAY NIGHT AND WEDNESDAY...MVFR AND IFR CONDITIONS ARE POSSIBLE ALONG WITH A CHANCE OF LIGHT RAIN. SOME LIGHT SNOW MAY FALL ON TUESDAY NIGHT, ESPECIALLY AROUND KRDG AND KABE. && .MARINE... HIGH PRESSURE WILL SHIFT TO OUR EAST TODAY ALLOWING FOR A SOUTHERLY FLOW TO DEVELOP. A WARM FRONT WILL ARRIVE TONIGHT, AND A WAA PATTERN WILL OCCUR TODAY THROUGH TONIGHT. AS THE WAA STRENGTHENS, A LOW-LEVEL JET /925 MB/ ON THE ORDER OF 30-35 KNOTS IS FORECAST TO MOVE ACROSS THE AREA LATER TONIGHT. THE FORECAST SOUNDINGS DO SHOW THE POTENTIAL FOR GUSTS TO AROUND 25 KNOTS TO OCCUR FOR A TIME TONIGHT. WHILE WE WILL BE WITHIN A WAA PATTERN, IT APPEARS THAT SMALL CRAFT ADVISORY CRITERIA WILL BE MET ON THE OCEAN ZONES. IN ADDITION, THE INCREASING SOUTHERLY FLOW WILL BUILD THE SEAS THROUGH TONIGHT. AFTER COLLABORATION WITH WFO`S OKX AND AKQ, WE ISSUED A SMALL CRAFT ADVISORY STARTING AT 23Z TONIGHT FOR JUST THE OCEAN ZONES. OUTLOOK... SUNDAY...A SMALL CRAFT ADVISORY IS IN EFFECT ON OUR OCEAN WATERS FOR A SOUTHWEST WIND GUSTING TO 25 OR 30 KNOTS AND WAVE HEIGHTS BUILDING NEAR 5 FEET. WIND SPEEDS SHOULD BE SLIGHTLY LOWER ON DELAWARE BAY AND NO ADVISORY IS IN EFFECT THERE. SUNDAY NIGHT...WINDS AND SEAS ARE FORECAST TO DECREASE SLOWLY. HOWEVER, THE SMALL CRAFT ADVISORY MAY EVENTUALLY NEED TO BE EXTENDED. MONDAY THROUGH TUESDAY...ANOTHER SMALL CRAFT ADVISORY MAY BE NEEDED AS A COLD FRONT PUSHES THROUGH OUR REGION. TUESDAY NIGHT AND WEDNESDAY...NO MARINE HEADLINES ARE ANTICIPATED. && .EQUIPMENT... THE WSR-88D LOCATED AT FORT DIX, NEW JERSEY (KDIX) REMAINS OUT OF SERVICE. WE ARE WAITING ON REPLACEMENT PARTS AND WE HOPE TO HAVE THE RADAR REPAIRED BY THE END OF THE DAY. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 PM EST SUNDAY FOR ANZ450>455. && $$ SYNOPSIS...IOVINO NEAR TERM...GORSE SHORT TERM...GORSE LONG TERM...IOVINO AVIATION...GORSE/IOVINO MARINE...GORSE/IOVINO EQUIPMENT...IOVINO
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
936 PM EST SUN NOV 30 2014 ...ANOTHER ROUND OF DENSE FOG LIKELY LATE TONIGHT AND EARLY MONDAY MORNING... .SYNOPSIS... HIGH PRESSURE WILL PREVAIL TONIGHT THROUGH MONDAY. A COLD FRONT WILL ADVANCE FROM THE NORTH TUESDAY...FOLLOWED BY A WEAK WEDGE OF HIGH PRESSURE. A STRONGER WEDGE OF HIGH PRESSURE WILL DEVELOP LATE WEEK INTO NEXT WEEKEND. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... IT APPEARS A WIDESPREAD DENSE FOG EVENT IS IN THE OFFING FOR MUCH OF THE AREA TONIGHT. THE BOUNDARY LAYER HAS DECOUPLED WITH CALM WINDS NOW BEING REPORTED AT ALL STATIONS PER 01/02Z SURFACE OBSERVATIONS. KCLX VAD WIND PROFILE SHOWS LIGHT/VARIABLE WINDS UP TO 4 KFT...SUGGESTING VERY LITTLE WIND EXISTS EVEN ATOP THE NOCTURNAL INVERSION. ABUNDANT LOW-LEVEL MOISTURE IS IN PLACE WITH DEWPOINTS RUNNING ABOUT 8-12 DEGREES HIGHER THAN 24 HOURS AGO. CLEAR SKIES...RICH LOW-LEVEL MOISTURE AND CALM WINDS WILL SUPPORT ANOTHER ROUND OF DENSE FOG--SIMILAR...IF NOT MORE DENSE/WDSPRD... THAN WHAT OCCURRED THIS MORNING. HIGH RESOLUTION DATA SETS INCLUDING THE RAP AND H3R HAVE BEEN CONSISTENT FOR MANY CONSECUTIVE RUNS NOW IN THEIR DEPICTION OF WIDESPREAD DENSE FOG ENCOMPASSING ALL OF SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA AFTER MIDNIGHT... ESPECIALLY FROM 2-3 AM ON. GOES-EAST IFR PROBABILITIES HAVE BEEN STEADILY INCREASING EAST OF I-95 OVER THE PAST FEW HOURS AND A FEW OBSERVATION SITES HAVE BEEN REPORTING VSBYS AS LOW AS 2 MILES ALREADY...SUGGESTING DENSE FOG INITIATION HAS BEGUN. WE SERIOUSLY CONSIDERED ISSUING A DENSE FOG ADVISORY FOR THE COUNTIES ALONG AND EAST OF I-95 AS THIS AREA WILL LIKELY SEE DENSE FOG FIRST...BUT PER COORDINATION WITH WFOS COLUMBIA...WILMINGTON AND JACKSONVILLE...WE WILL HOLD OFF FOR A BIT LONGER TO TRY AND BETTER CAPTURE TIMING. THE SPECIAL WEATHER STATEMENT WILL BE REISSUED INSTEAD. THE REST OF THE FORECAST IS ON TRACK. FOR THE EARLY EVENING UPDATE... * MADE MINOR ADJUSTMENTS TO HOURLY DEWPOINTS AND TEMPERATURES. * REISSUED A SPECIAL WEATHER STATEMENT TO HIGHLIGHT THE POTENTIAL FOR A WIDESPREAD DENSE FOG EVENT EARLY MONDAY. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... MONDAY...THE PATTERN AT THE SURFACE AND ALOFT WILL BE TRANSITIONING THROUGH THE DAY...AS DEEP LAYER RIDGING RETREATS FARTHER INTO THE ATLANTIC AHEAD OF A COLD FRONT APPROACHING FROM THE NORTHWEST. ONCE FOG DISSIPATES BY MID MORNING...MOSTLY CLEAR TO PARTLY CLOUDY SKIES WILL ALLOW SUFFICIENT INSOLATION WITHIN WARM SOUTHWEST FLOW TO SUPPORT ANOTHER UNSEASONABLY WARM DAY. WILL ADVERTISE HIGH TEMPERATURES PEAKING IN THE LOW TO MID 70S AWAY FROM THE LOCALLY COOLER COASTLINE. WILL NEED TO MONITOR THE POTENTIAL FOR FOG DEVELOPMENT AFTER MIDNIGHT...AS SEVERAL GUIDANCE SOURCES SUGGEST AREAS OF FOG COULD AGAIN IMPACT PORTIONS OF THE FORECAST AREA ONCE LOW LEVEL MOISTURE BECOMES TRAPPED BENEATH THE INVERSION. EXPECT MILDER LOW TEMPERATURES RANGING FROM THE UPPER 40S TO LOW 50S. TUESDAY...THE FRONT WILL LIKELY STALL IN THE VICINITY AND FORM THE LEADING EDGE OF AN INLAND WEDGE OF HIGH PRESSURE BUILDING DOWN THE LEE OF THE APPALACHIANS. THE PARENT SURFACE HIGH WELL TO THE NORTH WILL BE RATHER TRANSIENT IN NATURE...AND THUS THERE IS SOME UNCERTAINTY REGARDING THE STRENGTH OF THE WEDGE AND ITS ASSOCIATED SENSIBLE WEATHER IMPACTS. PREFER TO MAINTAIN PERSISTENCE AT THIS TIME AND INDICATE A RATHER SHARP TEMPERATURE GRADIENT FROM NORTHWEST TO SOUTHEAST...AS IS EXPECTED IN A WEDGE TYPE SCENARIO. WILL ADVERTISE HIGH TEMPERATURES RANGING FROM THE LOW 60S CHARLESTON TRI COUNTY REGION TO THE LOW 70S FARTHER SOUTH NEAR THE ALTAMAHA RIVER IN GEORGIA. ANY MEASURABLE PRECIPITATION IS EXPECTED TO REMAIN OVER THE MARINE ZONES AND POSSIBLY THE ADJACENT COASTLINE...CLOSEST TO MOISTURE CONVERGENCE WITHIN A WEAK COASTAL TROUGH. THE MAJORITY OF THE FORECAST AREA WILL SEE MOSTLY CLOUDY SKIES THROUGH THE NIGHT...KEEPING LOW TEMPERATURES IN THE UPPER 40S INLAND TO THE LOW 50S NEAR THE COAST. WEDNESDAY...THE CENTER OF THE SURFACE HIGH WILL SHIFT OFF THE NEW ENGLAND COAST...WHILE THE INLAND WEDGE STEADILY WEAKENS AND BECOMES ORIENTED ALONG THE MID ATLANTIC AND SOUTHEAST COAST. EXPECT THE TEMPERATURE GRADIENT TO BE LESS DEFINED AS A RESULT...WITH HIGHS RANGING FROM THE THE UPPER 60S TO NEAR 70 DEGREES. CLOUDS COULD LINGER FOR MUCH OF THE DAYTIME PERIOD...ESPECIALLY INLAND...WHILE RAIN CHANCES REMAIN LESS THAN A MENTIONABLE 15 PERCENT. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... THE UPPER PATTERN BECOMES MORE AMPLIFIED LATE IN THE WEEK INTO THE WEEKEND THOUGH THE COLD AIR REMAINS WELL TO THE NORTH. CANADIAN HIGH PRESSURE WILL CONTINUE TO TRY TO WEDGE DOWN THE EASTERN SEABOARD BUT WITH A BUILDING 850 MB RIDGE AND LACK OF MOISTURE OR FORCING TO PRODUCE PRECIPITATION...TEMPERATURES WILL STAY NEAR NORMAL ALBEIT WITH GREATER CLOUD COVER. HIGHS WILL GENERALLY BE IN THE MID/UPPER 60S WITH LOWS IN THE MID/UPPER 40S. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... BIGGEST CONCERN IS FOR DENSE FOG TO AFFECT THE TERMINALS. CONFIDENCE IS HIGHEST AT KSAV WHERE VSBYS MAY DROP TO LESS THAN 1/4SM WITH VERTICAL VISIBILITIES 100 FT OR LESS. CONFIDENCE IS NOT AS HIGH AT KCHS...BUT MODELS CONTINUE TO TREND WITH LOWER CONDITIONS. FOR THE 00Z TAF CYCLE...WILL MAINTAIN LIFR VSBYS/CIGS AT KSAV FROM ROUGHLY 09-14Z AND INTRODUCE PREVAILING IFR VSBYS/CIGS WITH TEMPO LIFR AT KCHS TO TREND. BOTH TERMINALS MAY EVENTUALLY TANK PRIOR TO SUNRISE. THE FOG IS FORECAST TO LIFT 14-15Z WITH VFR CONDITIONS PREVAILING THEREAFTER. EXTENDED AVIATION OUTLOOK...VISIBILITY RESTRICTIONS ARE POSSIBLE IN FOG INTO EARLY TUESDAY. MVFR OR LOWER CEILINGS ARE POSSIBLE TUESDAY INTO WEDNESDAY DUE TO LOW-LEVEL MOISTURE IN THE WAKE OF THE COLD FRONT. VISIBILITY AND/OR CEILING RESTRICTIONS POSSIBLE THURSDAY MORNING. && .MARINE... TONIGHT...VARIABLE WINDS 5 KT OR LESS WITH SEAS 1-2 FT WILL DOMINATE THE WATERS TONIGHT. AREAS OF FOG ARE LIKELY NEAR THE COAST WITH VSBYS 1-3 NM...LOCALLY LESS THAN 1 NM. IN THE CHARLESTON HARBOR...VSBYS COULD DROP TO LESS THAN 1/2 NM. A MARINE DENSE FOG ADVISORY MAY VERY WELL BE NEEDED OVERNIGHT. MONDAY THROUGH FRIDAY...WEAK HIGH PRESSURE WILL PERSIST INTO MONDAY. A BACKDOOR COLD FRONT WILL THEN DESCEND INTO THE WATERS TUESDAY...WITH A WEDGE OF HIGH PRESSURE BUILDING IN FROM THE NORTH AND TIGHTENING THE GRADIENT WITHIN WEAK COLD ADVECTION. MARGINAL SMALL CRAFT ADVISORY CONDITIONS ACROSS THE OFFSHORE WATERS ARE POSSIBLE TUESDAY NIGHT...MAINLY FOR SEAS BUILDING TO 6 FT OVER OFFSHORE GEORGIA WATERS TUESDAY NIGHT THROUGH MIDDAY WEDNESDAY. THEREAFTER...THE GRADIENT RELAXES QUITE A BIT...AND THE POSSIBILITY FOR ADDITIONAL ADVISORIES WANES LATE IN THE WEEK. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && $$ ST
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
352 PM CST SAT NOV 29 2014 .SHORT TERM... 258 PM CST THROUGH MONDAY... FLOW ALOFT REMAINS ZONAL THROUGH THIS WEEKEND WITH A TROUGH AXIS PASSING OVER WISCONSIN AND MICHIGAN MONDAY. THE SURFACE PATTERN IS A BIT BUSIER WITH A LOW OVER NORTHEAST MINNESOTA THIS AFTERNOON. ITS WARM FRONT IS JUST NORTH OF THE CWA OVER SOUTHERN WI. WE ARE ENJOYING THE WARM SECTOR WITH BREEZY SOUTH WINDS AND TEMPERATURES IN THE 50S ACROSS MUCH OF THE CWA. STRATOCU IS SLOWLY MOVING NORTH BUT HAVING A DIFFICULT TIME BUILDING OVER THE CWA. A NICE BAND OF CIRRUS IS ALSO IN PLACE...AND STILL EXPECTING CLOUD COVER TO THICKEN OVERNIGHT. TEMPERATURES WILL ONLY COOL INTO THE UPPER 30S IN NORTH CENTRAL IL TO THE UPPER 40S IN EAST CENTRAL IL AND NW INDIANA. ALSO EXPECTING TO SEE AREAS ALONG AND EAST OF I-55 TO WARM SLIGHTLY OVERNIGHT AS WAA CONTINUES TO PUSH WARMER AIR INTO THE REGION. PATCHY DRIZZLE WILL ACCOMPANY THIS WARM AIR PUSH SO HAVE PATCHY DRIZZLE ACROSS THE CWA AFTER MIDNIGHT. THE LOW CONTINUES NORTHEAST REACHING JAMES BAY SUNDAY MORNING AND ITS COLD FRONT SWINGS THROUGH THE CWA TOMORROW. THE MAIN IMPACT FROM THE FRONT WILL BE FALLING TEMPERATURES. BY EVENING...TEMPERATURES WILL RANGE FROM THE LOWER 20S IN NORTH CENTRAL IL TO AROUND FREEZING IN NW INDIANA. COULD SEE SOME LIGHT RAIN ALONG THE COLD FRONT...BUT NOT OVERLY IMPRESSED WITH THE AMOUNT OF MOISTURE OR FORCING. THEREFORE WENT WITH SLIGHT CHANCE TO LOW END CHANCE POPS. TOMORROW WILL NOT BE A WASHOUT. AT MOST EXPECTING SPOTTY LIGHT RAIN THAT WILL ONLY DAMPEN THE SURFACE. GUSTY NW WINDS ALSO ACCOMPANY THE FRONT. CLOUDS CLEAR OUT SUNDAY EVENING AND NIGHT LEADING TO A CHILLY NIGHT WITH LOWS IN THE LOWER TEENS TO LOWER 20S. GUSTY NW WINDS WITH TOP SPEEDS UP TO 25 MPH WILL PERSIST OVERNIGHT LEADING TO WIND CHILLS IN THE SINGLE DIGITS. AREAS IN NORTH CENTRAL IL MAY HAVE WIND CHILLS JUST BELOW ZERO EARLY MONDAY MORNING. THE REST OF MONDAY WILL BE DRY WITH WINDS DIMINISHING AS HIGH PRESSURE MOVES OVERHEAD. HIGH TEMPERATURES WILL BE IN THE 20S. JEE && .LONG TERM... 258 PM CST MONDAY NIGHT THROUGH SUNDAY... THE EXTENDED IS A BIT MORE ACTIVE WITH ANOTHER TROUGH PASSING TO OUR NORTH WEDNESDAY AND A WEAKENING SHORTWAVE TROUGH THURSDAY OR FRIDAY. THE SURFACE HIGH SHIFTS EAST MONDAY NIGHT WITH A LOW PASSING TO OUR NORTH TUESDAY NIGHT INTO WEDNESDAY. ITS COLD FRONT SWINGS THROUGH EARLY WEDNESDAY WITH ANOTHER ROUND OF HIGH PRESSURE MOVING IN THURSDAY. LOW PRESSURE PASSES WELL TO OUR SOUTH LATE NEXT WEEK...BUT IT MAY BRING A MIX OF PRECIP TYPES TO THE REGION. FIRST THINGS FIRST...THE COLD CONTINUES MONDAY NIGHT WITH SINGLE DIGIT LOWS POSSIBLE OVER NORTH CENTRAL IL. WINDS WILL BE WEAK...BUT WIND CHILLS BELOW ZERO ARE POSSIBLE OVER NORTHERN IL. CLOUD COVER INCREASES AS A LOW PASSES OVER ONTARIO TUESDAY NIGHT AND ITS COLD FRONT SWINGS THROUGH WEDNESDAY. REALLY ONLY EXPECTING A WIND SHIFT WITH THIS FRONT AS HIGH TEMPS WEDNESDAY WILL BE IN THE MID 30S TO AROUND 40. HIGH PRESSURE MOVES OVERHEAD FOR A BRIEF PERIOD THURSDAY WITH HIGH TEMPS IN THE 30S AGAIN. PRECIP CHANCES INCREASE THURSDAY AND THURSDAY NIGHT AS THE HIGH DEPARTS AND A WEAKENING SHORTWAVE TROUGH MOVES OVERHEAD. A SURFACE LOW WILL ALSO BE MOVING FROM OKLAHOMA TO THE LOWER OHIO RIVER VALLEY FRIDAY AFTERNOON. HIGH TEMPS WILL BE ABOVE FREEZING BOTH DAYS WHILE LOW TEMPS WILL BE BELOW FREEZING. SOME MODELS ALSO FEATURE A WARM LAYER ALOFT THURSDAY NIGHT. SO THIS SYSTEM COULD BRING A MIX OF RAIN AND SNOW THURSDAY WITH RAIN...SNOW...ICE PELLETS...AND QUITE POSSIBLY FREEZING RAIN THURSDAY NIGHT. IT IS TOO FAR OUT TO GET TOO SPECIFIC AS TO WHAT WHEN SO WENT WITH A MIX IN THE GRIDS. THE WARM LAYER DOES APPROACH +3C BUT ONLY BRIEFLY SO HAVE HIGHER CONFIDENCE IN PARTIAL MELTING AND ICE PELLETS VERSUS FREEZING RAIN. HAVE LIMITED CONFIDENCE IN THE COVERAGE OF PRECIP THURSDAY THROUGH FRIDAY DUE TO MODEL DIFFERENCES. WE DRY OUT FOR THE WEEKEND WITH ANOTHER ROUND OF HIGH PRESSURE AND HIGH TEMPS AROUND NORMAL. JEE && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 22Z... * SMALL CHANCE FOR MVFR CIGS THIS EVENING...A LITTLE HIGHER CHANCE AT MDW. * SOUTH-SOUTHWEST WINDS GUSTING 20-25 KT THROUGH 00Z. * MVFR CIGS EXPECTED LATE TONIGHT OR TOWARD DAYBREAK WITH COLD FRONT PASSAGE. SCATTERING EXPECTED SUNDAY AFTERNOON. * WINDS SHIFT NORTHWEST WITH GUSTS TO AROUND 20 KT MID MORNING SUNDAY. MDB/MTF //DISCUSSION...UPDATED 1930Z... STRATOCU DEVELOPMENT HAS BEEN MINIMAL THUS FAR AND DO NOT EXPECT MORE THAN FEW-SCT COVERAGE OVER THE NEXT FEW HOURS. STRATUS TO THE SOUTH OF THE TERMINALS CONTINUES TO TRACK NORTHEAST AND WILL REMAIN TO THE SOUTHEAST THROUGH THE AFTERNOON. FROM 18Z... CIG TRENDS STILL REMAIN THE MAIN CHALLENGE. A LOOK OUT THE WINDOW SHOWS SOME STRATOCU DEVELOPING TO THE NORTH OF THE OFFICE WITH ORD NOW SHOWING SCT020. THE MAIN QUESTION IS HOW MUCH MORE STRATOCU WILL FORM. LATEST AIRCRAFT SOUNDINGS SHOWS A SEVERAL HUNDRED FOOT THICK LAYER OF SATURATION SO A BRIEF WINDOW OF BKN SKIES IS STILL POSSIBLE. WILL CONTINUE WITH A BKN LAYER FOR A FEW HOURS BUT THIS MAY BE A BIT PESSIMISTIC...ESPECIALLY ON DURATION. OTHERWISE EXPECT VFR TO RETURN INTO MUCH OF THE OVERNIGHT. A COLD FRONT WILL APPROACH LATE AND MVFR DOES LOOK TO RETURN AND MAY OCCUR SEVERAL HOURS LATER THAN CURRENTLY FORECAST...CLOSER TO FRONTAL PASSAGE TIME. FORECAST SOUNDINGS CONTINUE TO SHOW ABUNDANT LOW LEVEL MOISTURE AS THEY DID LAST NIGHT FOR THIS MORNING. WITH NO APPRECIABLE CHANGE IN AIRMASS OVERNIGHT WITH TEMPS STEADY OR EVEN WARMING FOG AND LOW STRATUS DOES NOT APPEAR LIKELY. HOWEVER...DEWPOINTS/MOISTURE CONTENT WILL BE HIGHER SO WILL NEED TO MONITOR. A COLD FRONT WILL CROSS THE AREA SUNDAY MORNING SHIFTING WINDS TO THE NORTHWEST. MAY NEED TO TWEAK THE TIMING SOMEWHAT BUT HAVE DECENT CONFIDENCE IN TIMING IN THE TAF FOR NOW. MVFR CLOUD COVER LOOKS TO ACCOMPANY THE FRONT AND LINGER FOR AT LEAST SEVERAL HOURS BEHIND IT. IT DOES APPEAR THAT THIS WILL BE ABLE TO SCATTER DURING THE AFTERNOON. WINDS WILL LIKELY GUST TO AROUND 20 KT. MDB //ORD AND MDW CONFIDENCE...UPDATED 22Z... * LOW IN MVFR CIGS THIS EVE...AS THEY MAY PASS JUST SOUTH AND EAST OF TERMINALS. * HIGH IN WIND FORECAST THROUGH TONIGHT. * MEDIUM-HIGH IN MVFR CIGS OCCURRING SUNDAY MORNING. LOW CONFIDENCE IN ARRIVAL TIME...MAY NEED TO SLOW IT DOWN. MEDIUM- CONFIDENCE IN SCATTERING SUNDAY AFTERNOON. * HIGH IN WIND SHIFT TO NORTHWEST WITH FRONTAL PASSAGE LATER SUNDAY MORNING. MEDIUM CONFIDENCE IN TIMING...MAY NEED TO BE ADJUSTED SLIGHTLY. MDB/MTF //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...MAINLY VFR. MONDAY...VFR. NORTHWEST WINDS BECOMING NORTH BY EVENING. TUESDAY...VFR. SOUTH WINDS. WEDNESDAY...VFR. WEST WINDS. THURSDAY...CHANCE OF RAIN AND SNOW. EAST WINDS. FRIDAY...CHANCE OF RAIN OR SNOW BEACHLER && .MARINE... 214 PM CST SOUTHERLY WINDS WILL REMAIN ELEVATED IN THE 20 TO 30 KT RANGE OVER THE LAKE THROUGH MUCH OF TONIGHT AS AN AREA OF LOW PRESSURE TRACKS NORTHEASTWARD FROM THE DAKOTAS TO NEAR JAMES BAY. THE CURRENT SMALL CRAFT ADVISORY GOES THROUGH 10 PM THIS EVENING...AND OVERALL APPEARS TO BE A GOOD TIMING. HOWEVER...THE INDIANA SHORES MAY NEED TO BE EXTENDED A FEW MORE HOURS...AS IT APPEARS THE WINDS COULD REMAIN ELEVATED THERE. FOR NOW I WILL LET THE EVENING SHIFT GET A BETTER HANDEL ON WIND TRENDS WITH SUNSET TO SEE IF A TIME EXTENSION MAY BE JUSTIFIED. THE SURFACE LOW WILL DRIVE A COLD FRONT SOUTHWARD ACROSS LAKE MICHIGAN DURING THE ON SUNDAY MORNING. MUCH COLDER AIR AND STRONG NORTHERLY WINDS WILL SET UP IN THE WAKE OF THIS FRONT AS A STOUT 30.71+ INCH HIGH BUILDS OVER THE PLAINS AND UPPER MIDWEST. THIS SHOULD RESULT IN 30 KT WINDS LATER SUNDAY INTO EARLY MONDAY...THOUGH A FEW GALE FORCE GUSTS CANT BE RULED OUT SUNDAY NIGHT AS THE HEART OF THE COLD AIRMASS SPILLS OVER THE LAKE. THE SURFACE HIGH WILL SHIFT EASTWARD OVER LAKE MICHIGAN BY MONDAY EVENING...SETTING UP A PERIOD OF LIGHT WINDS MONDAY NIGHT. HOWEVER...AS THIS HIGH SHIFTS EAST OF THE LAKE BY EARLY TUESDAY...THE WINDS WILL BECOME SOUTHERLY AND INCREASE ON TUESDAY AS ANOTHER DECENT STORM SYSTEM TRACKS NORTHEASTWARD INTO SOUTHERN CANADA. THIS SHOULD RESULT IN THE STRONGEST WINDS...TO 35 TO 40 KT GALES...ACROSS THE NORTHERN HALF OF LAKE MICHIGAN ON TUESDAY AND TUESDAY EVENING. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 10 PM SATURDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 313 PM CST Sat Nov 29 2014 .SHORT TERM...(Tonight) ISSUED AT 313 PM CST SAT NOV 29 2014 A mild day across the forecast area, ahead of the sharp cold front that will be coming in on Sunday. Temperatures have reached the mid to upper 50s in most areas, and are seeing a couple lower 60s over the far southwest CWA near Jacksonville. The expansive area of stratocumulus has spread into northern Indiana, and most of the forecast area southeast of a Champaign to Pana line is mostly cloudy. Areas further west continue to see a steady stream of cirrus moving in from the central Plains, with some filtered sunshine. Highest winds remain across areas east of I-55 where gusts have exceeded 30 mph at times. Not a lot of change made to the overnight forecast. The latest HRRR model lingers the lower clouds across the eastern CWA through most of the evening. Forecast soundings keep a tight inversion below 900 mb into mid evening before the clouds move out, and some sprinkles or drizzle may get squeezed out this evening. Overnight temperatures to remain quite mild east of I-55, fairly steady in the lower 50s. West of I-55, lows in the 40s anticipated, although the cold front will be moving into the Galesburg area around sunrise. && .LONG TERM...(Sunday through Saturday) ISSUED AT 313 PM CST SAT NOV 29 2014 The 12z models are speeding up the strong cold front on Sunday. Consensus now shows the front reaching a line from Champaign to Taylorville by 18z/Noon, when previous runs had the front barely to Galesburg by then. The frontal passage appears to be dry until closer to noon, when moisture pooling increases as the front approaches the intensifying low level jet across far SE IL. Lift with the frontal passage appears weak in general, but as the day progresses there is some evidence of jet coupling over SE IL between the 300mb 140kt jet and the 850mb 45kt jet. Therefore, we lowered PoPs Sunday morning and delayed them until after 15z keeping them only in the vicinity of the front. Chance PoPs were kept in the afternoon, but once again only in close proximity to the front as it progresses to the SE. Precip type should remain all rain through the day, as dry air and subsidence shut down precipitation behind the cold front. High temps will vary widely across the forecast area with the passage of the front during normal peak heating. Areas NW of the IL river may even see temps begin to fall before the Noon hour, while SE areas will see temps climb into early afternoon under strong SW winds, despite widespread cloud cover. High temps will barely reach 40 near GBG, while the Lawrenceville area climbs into the low 60s ahead of the front. Blustery NW winds behind the front will usher in the 1047mb cold Canadian high Sunday night. There remains some question to if the precipitation will continue fall after the temps fall below freezing, and trends are favoring lower chances of any freezing rain or freezing drizzle. Snow does not appear to be a precip-type option due to the lack of ice crystals to feed into the shallow surface moisture. Hazardous travel could still develop Sunday night and into the Monday morning commute, as any lingering moisture on surfaces after the rain ends could freeze and create slippery roads and sidewalks. The continued surge of cold air on Monday will keep highs mainly in the 20s, with some low 30s S of I-70. Little to no precipitation is expected on Monday, with the NAM/GFS/GEM consensus being dry in our forecast area, while the ECMWF holds onto precip near LWV early Monday. Therefore, we reduced PoPs to a narrow stripe of slight chances in the far SE for now. Lows Monday night will be well below normal, with single digits possible near GBG and low 20s S of I-70. The center of the surface high will progress east across the Great Lakes on Tuesday, shifting winds from east-southeast to south by afternoon. Mid-level warming and mixing of that air to the ground will help push most areas above freezing for highs. cloud cover is projected to increase for areas SE of the IL river, which could temper the warming slightly. A weak cold front is now projected to approach N Illinois from the NW on Wednesday, as relatively zonal flow aloft pushes various shortwaves toward southern IL. That will work to keep the trend of increasing cloud cover on Wednesday, but southerly winds should help highs reach the upper 30s north of Peoria and low to mid 40s south of there. Any rainfall on Wed should remain south of our forecast area. The extended forecast is coming under better agreement with the 12z model suite. The GFS and ECMWF both show weak low pressure in the Ark-La-Tex area progressing toward S IL Wed night through Thursday night. The Canadian GEM is also indicating that pattern but just 6-12 hours later. That scenario is not far off from the current precip timing. We kept the slight chances Wed night south of I-74 and chance PoPs in most areas Thur and Thur night. Precip-type remains a question mark, with the GFS indicating an extended period of freezing rain possible, mainly north of I-72. A surge of warm air could change the precip to all rain Thursday afternoon, with a return to freezing rain chances from N to S for Thursday night as cold air pushes back to the south. The ECMWF appears warmer than the GFE, which would limit any period of freezing rain. The mid to late week forecast will need to be watched closely for the potential of an icing event. && .AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon) ISSUED AT 1132 AM CST SAT NOV 29 2014 Area of MVFR ceilings continues to advect northeast across east central Illinois and is about to move into KCMI. HRRR guidance suggests it should stay there much of the afternoon. Trajectories of the cloud deck indicate that KDEC will be on the western edge and would not be surprised to see a couple hours of ceilings below 3000 feet there. Otherwise, gusty south winds of 20-25 knots will settle down late afternoon, but most areas will see the winds stay above 10 knots through the night. A sharp cold front will move in from the northwest Sunday morning, with an area of MVFR ceilings likely behind it as well as increasing northwest winds. Right now, the TAFs only have the front through KPIA before the end of the forecast period, but areas from KSPI-KBMI may see the winds switching toward 18Z. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Geelhart LONG TERM...Shimon AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1214 PM CST SAT NOV 29 2014 .SHORT TERM... 338 AM CST MAIN FORECAST CONCERNS/CHALLENGES ARE WITH POSSIBLE STRATUS AND HIGH TEMPS TODAY...CONTINUED WARMER TEMPS TONIGHT INTO SUNDAY WITH RAIN CHANCES BEFORE COLD RETURNS BY THE END OF THE PERIOD. QUIETER CONDITIONS IN PLACE EARLY THIS MORNING WHILE ONLY HIGH LEVEL CLOUD COVER STREAMS OVERHEAD...WITH ONLY PATCHY FOG BEING OBSERVED OVER NORTHERN ILLINOIS. AS STRONG WAA PERSISTS ACROSS THE REGION...SURFACE TEMPS ARE EITHER HOLDING NEARLY STEADY OR RISING SLIGHTLY...AND IS OCCURRING AS SURFACE WARM FRONT TO THE SOUTHWEST IS APPROACHING THE SOUTHERN CWA. TEMPS WILL LIKELY SLOWLY WARM OVER THE NEXT SEVERAL HOURS AS THIS FRONT CONTINUES TO LIFT NORTHEAST ACROSS THE CWA AND THERMAL AXIS SETTLES IN...SETTING THE STAGE FOR A MUCH MILDER DAY. HAVE MADE LITTLE TO NO CHANGES TO GOING FORECAST HIGH TEMPS IN THE 50S TODAY...BUT WITH STILL SOME CONCERNS THAT LOW LEVEL STRATUS COULD LIMIT WARMING IN SOME LOCATIONS. CURRENT MID/HIGH LEVEL CLOUD COVER WILL CONTINUE TO STREAM OVERHEAD THROUGH THE NEXT SEVERAL HOURS AND PROVIDE PARTLY CLOUDY SKIES EARLY THIS MORNING...BUT AS WARM FRONT LIFTS NORTH...STRATUS WILL TRY TO DEVELOP ACROSS THE REGION. LOOKING UPSTREAM...LITTLE IF ANY STRATUS CURRENTLY IN PLACE...BUT ONCE AGAIN GUIDANCE STILL TRYING TO INDICATE THAT LOW STRATUS WILL DEVELOP BY MID TO LATE MORNING. CURRENT THINKING IS THAT DEVELOPMENT WILL OCCUR LATER THIS MORNING BUT WITH THE BETTER AXIS OF MORE SOLID CLOUD COVER STAYING TO THE SOUTHEAST OF THE CWA...WITH AREAS IN NORTHWEST INDIANA POSSIBLY GETTING INTO MORE PARTLY SUNNY SKIES. WITH ONLY PARTLY CLOUDY SKIES THEN EXPECTED INTO THE AFTERNOON...SEE NO REASON WHY MOST AREAS WILL NOT SEE THESE WARMER TEMPS. TONIGHT APPEARS TO BE ANOTHER PERIOD WITH A NONDIURNAL TREND LIKELY...WITH MILD CONDITIONS STILL IN PLACE. INCREASING MOISTURE AND LIFT SHOULD ALLOW FOR CLOUDIER SKIES AS WELL AS THE POSSIBILITY FOR PATCHY LIGHT DRIZZLE...MAINLY FOR EAST CENTRAL ILLINOIS AND NORTHWEST INDIANA. MILDER CONDITIONS ONCE AGAIN POSSIBLE FOR THE SOUTHEAST CWA SUNDAY MORNING AS PROGRESSING SURFACE LOW SHIFTS EAST ACROSS THE GREAT LAKES REGION OUT AHEAD OF APPROACHING UPPER LEVEL TROUGH...AND SURFACE COLD FRONT SURGES SOUTHEAST TOWARDS THE CWA. LIGHT RAIN WILL BE POSSIBLE OVER THE SOUTHEAST CWA SUNDAY MORNING INTO EARLY SUNDAY AFTERNOON AS THE COLD FRONT PUSHES THROUGH THE CWA DURING THIS TIME. EXPECT TEMPS TO BE BACK IN THE 20S ACROSS NORTHERN ILLINOIS BY MID AFTERNOON WITH THIS TREND CONTINUING FOR THE REMAINING CWA...AS BELOW NORMAL TEMPS RETURN SUNDAY NIGHT INTO MONDAY. RODRIGUEZ && .LONG TERM... 338 AM CST DRY CONDITIONS WILL START THE PERIOD WITH SOME SLIGHT WARMING ANTICIPATED...AS BACKING FLOW WILL ALLOW FOR A RETURN OF A WARMER AIRMASS. EXPECT HIGH TEMPS BACK IN THE UPPER 30S WEDNESDAY AND THURSDAY...BUT WITH CHANCES FOR PRECIP RETURNING BY THURSDAY. STILL SOME DIFFERENCES WITH REGARDS TO TIMING OF THIS SYSTEM AS WELL AS THERMAL PROFILES. BOTH OF THESE DIFFERENCE WILL LIKELY PLAY INTO PRECIP TYPE DURING THIS TIME...WITH A WINTRY MIX APPEARING POSSIBLE AT THIS TIME. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * SCT MVFR CLOUDS DEVELOPING AND MAY BECOME BROKEN FOR A FEW HOURS INTO MID AFTERNOON. * SOUTH-SOUTHWEST WINDS GUSTING 20-25 KT THROUGH THE AFTERNOON. * MVFR CIGS EXPECTED LATE TONIGHT OR TOWARD DAYBREAK WITH COLD FRONT PASSAGE. SCATTERING EXPECTED SUNDAY AFTERNOON. * WINDS SHIFT NORTHWEST WITH GUSTS TO AROUND 20 KT MID MORNING SUNDAY. MDB //DISCUSSION...UPDATED 18Z... CIG TRENDS STILL REMAIN THE MAIN CHALLENGE. A LOOK OUT THE WINDOW SHOWS SOME STRATOCU DEVELOPING TO THE NORTH OF THE OFFICE WITH ORD NOW SHOWING SCT020. THE MAIN QUESTION IS HOW MUCH MORE STRATOCU WILL FORM. LATEST AIRCRAFT SOUNDINGS SHOWS A SEVERAL HUNDRED FOOT THICK LAYER OF SATURATION SO A BRIEF WINDOW OF BKN SKIES IS STILL POSSIBLE. WILL CONTINUE WITH A BKN LAYER FOR A FEW HOURS BUT THIS MAY BE A BIT PESSIMISTIC...ESPECIALLY ON DURATION. OTHERWISE EXPECT VFR TO RETURN INTO MUCH OF THE OVERNIGHT. A COLD FRONT WILL APPROACH LATE AND MVFR DOES LOOK TO RETURN AND MAY OCCUR SEVERAL HOURS LATER THAN CURRENTLY FORECAST...CLOSER TO FRONTAL PASSAGE TIME. FORECAST SOUNDINGS CONTINUE TO SHOW ABUNDANT LOW LEVEL MOISTURE AS THEY DID LAST NIGHT FOR THIS MORNING. WITH NO APPRECIABLE CHANGE IN AIRMASS OVERNIGHT WITH TEMPS STEADY OR EVEN WARMING FOG AND LOW STRATUS DOES NOT APPEAR LIKELY. HOWEVER...DEWPOINTS/MOISTURE CONTENT WILL BE HIGHER SO WILL NEED TO MONITOR. A COLD FRONT WILL CROSS THE AREA SUNDAY MORNING SHIFTING WINDS TO THE NORTHWEST. MAY NEED TO TWEAK THE TIMING SOMEWHAT BUT HAVE DECENT CONFIDENCE IN TIMING IN THE TAF FOR NOW. MVFR CLOUD COVER LOOKS TO ACCOMPANY THE FRONT AND LINGER FOR AT LEAST SEVERAL HOURS BEHIND IT. IT DOES APPEAR THAT THIS WILL BE ABLE TO SCATTER DURING THE AFTERNOON. WINDS WILL LIKELY GUST TO AROUND 20 KT. MDB //ORD AND MDW CONFIDENCE...UPDATED 18Z... * MEDIUM-HIGH CONFIDENCE IN SCT MVFR LEVEL CLOUDS DEVELOPING. MEDIUM CONFIDENCE THAT A PERIOD OF BKN COVERAGE OCCURS THEN SCATTERS LATER IN THE AFTERNOON. * HIGH CONFIDENCE IN WIND FORECAST THROUGH TONIGHT. * MEDIUM-HIGH CONFIDENCE IN MVFR CIGS OCCURRING SUNDAY MORNING. LOW CONFIDENCE IN ARRIVAL TIME...MAY NEED TO SLOW IT DOWN. MEDIUM-CONFIDENCE IN SCATTERING SUNDAY AFTERNOON. MDB //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...MAINLY VFR. MONDAY...VFR. NORTHWEST WINDS BECOMING NORTH BY EVENING. TUESDAY...VFR. SOUTH WINDS. WEDNESDAY...VFR. WEST WINDS. THURSDAY...CHANCE OF RAIN AND SNOW. EAST WINDS. FRIDAY...CHANCE OF RAIN OR SNOW BEACHLER && .MARINE... 243 AM CST HELD ONTO THE SMALL CRAFT ADVISORY FOR TODAY THROUGH THIS EVENING...ALTHOUGH IT APPEARS TO BE MARGINAL CONDITIONS AND COULD SEE SOUTH WINDS MAINLY HOVERING BETWEEN 20-25KT. HIGH PRESSURE HAS MOVED EAST ALONG THE EASTERN SEABOARD THIS MORNING...AND WILL CONTINUE TO PUSH EAST ACROSS THE WESTERN ATLANTIC. MEANWHILE A TROUGH OF LOW PRESSURE CENTERED OVER THE DAKOTAS IS EXPECTED TO DEEPEN AS IT LIFTS NORTHEAST ACROSS NORTHERN MINNESOTA THIS EVENING. A WARM FRONTAL BOUNDARY EXTENDS EAST FROM THIS LOW PRESSURE SYSTEM...AND WILL LIFT NORTH ACROSS THE SOUTHERN HALF OF LAKE MICHIGAN THIS EVENING. WITH MUCH WARMER AIR LIFTING NORTH ACROSS THE LAKE IT IS POSSIBLE THAT MIXING THE HIGHER WINDS TO THE SURFACE MAY BE A BIT OF A CHALLENGE LATER THIS EVENING. THE LOW WILL CONTINUE TO MOVE NORTHEAST AND DEEPEN SUNDAY MORNING...WHILE A TRAILING COLD FRONT APPROACHES LAKE MICHIGAN SUNDAY MID-MORNING. A STRONG RIDGE OF HIGH PRESSURE WILL BEGIN TO SLIDE SOUTH FROM THE CANADIAN ROCKIES SUNDAY. AS THE HIGH PRESSURE BUILDS EAST...THE GRADIENT MAY INCREASE ENOUGH LATE SUNDAY/EARLY MONDAY TO PRODUCE WINDS TO 30KT OR POSSIBLY A FEW GALE FORCE GUSTS. HIGH PRESSURE THEN BRINGS LIGHTER WINDS TO THE LAKE MONDAY MIDDAY. THEN THE HIGH PRESSURE QUICKLY SHIFTS EAST MONDAY NIGHT...WITH WINDS TURNING SOUTH/SOUTHWEST. ANOTHER LOW PRESSURE SYSTEM IS EXPECTED TO DEVELOP TUESDAY MORNING ACROSS THE CENTRAL PLAINS. BETWEEN THE RIDGE AND TROUGH THE GRADIENT OVER THE LAKE WILL QUICKLY INCREASE AND COULD PRODUCE A PERIOD OF GALE FORCE WINDS TUESDAY AFTERNOON. BEACHLER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 10 PM SATURDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 1132 AM CST Sat Nov 29 2014 .UPDATE... ISSUED AT 956 AM CST SAT NOV 29 2014 Area of low clouds has been spreading northeast out of the lower Ohio Valley this morning and was up to about I-70. Latest HRRR guidance continues to suggest this overspreading much of the CWA east of highway 51 into early afternoon, while areas further west primarily deal with a steady stream of cirrus clouds from the central Plains. Southerly winds already gusting 20-30 mph in areas east of the Illinois River and that will continue into the afternoon, boosting temperatures well into the 50s over the CWA. Have sent some updated zones/grids to tweak the cloud trends for today, and also to sharpen up the temperature trends for Sunday and Sunday night with the strong cold front. && .SHORT TERM...(Today) ISSUED AT 250 AM CST SAT NOV 29 2014 Southerly winds have prevailed through the night bringing mild conditions, at least compared to what occurred the past few mornings across central through southeast Illinois. The persistent southerly flow has resulted in a marked increase in the low level cloud cover over parts of Arkansas this morning with a north- northeast trajectory. Forecast soundings have indicated an increase in low level moisture for the past several runs which is being validated now over the lower Mississippi Valley. The last several runs of the HRRR model has brought the clouds northeast into about the eastern half of the forecast area by early this afternoon. Surface dew points over extreme southwest Missouri have risen into the mid and upper 40s early this morning and expect the persistent 1000-850 mb theta-e advection and moisture transport to bring the higher dew points and clouds northeast into our area later today. Despite the increase in clouds, temperatures are expected to warm into the low to mid 50s north to the upper 50s, possibly 60 degrees over parts of southwest Illinois this afternoon. Models for the past several days have hinted at some light QPF over parts of southeast Illinois with the significant moisture transport into our area. However, not seeing much in the way of lift with forecast soundings showing only the low level moisture trapped beneath a strengthening inversion today and tonight. Seems to be more of a setup for very light rain or drizzle over parts of southeast and east central Illinois and later this afternoon and tonight. && .LONG TERM...(Tonight through Friday) ISSUED AT 250 AM CST SAT NOV 29 2014 One more mild day across our area on Sunday before a strong cold front and associated 1047 mb high settles across the lower Great Lakes Sunday night and spends a few days early next week, before slight warmer weather returns for the balance of the forecast period. The strong Polar cold front looks on track for mainly Sunday afternoon along with light rain or drizzle chances just ahead and behind the frontal boundary. Best chances appear to be over the eastern half of the forecast area, mainly east of I-55, Sunday afternoon. Other than the low level moisture trapped beneath the rather strong inversion, not much moisture above, so looking more for drizzle or some very light rain Sunday afternoon into Sunday night. As the colder air settles south, there may be a brief period of some very light freezing rain or drizzle mainly over the I-70 corridor late Sunday night into the Monday morning commute. There may be some very light ice accumulations over extreme southeast Illinois just in time for the return to work and school Monday morning. Cold and dry conditions expected to settle over our area for Monday through Wednesday. We may see some lingering light precip Monday morning over the far southeast counties, but the front should get shunted well south of our area by Monday afternoon and evening ushering in some rather chilly temperatures again across the entire area Monday night. Lows will dip into the 10 to 15 degree range over the north half of the forecast area Tuesday morning with low to mid 20s common south. Quiet but chilly temperatures will be the story through Wednesday morning before we see a gradual moderating trend starting Wednesday afternoon as the upper flow becomes more zonal over the lower 48. Southerly return flow develops ahead of the next shortwave on Thursday bringing in warming temperatures but also chances for precipitation mainly from Wednesday night through Friday as a series of weak impulse translate east in the zonal flow across the center of the country. With the flow deamplifying during this period, we are seeing some timing differences with respect to the sensible weather associated with these fast moving and relatively weak waves, especially towards the end of the week. However, with a zonal flow pattern seen over western Canada and medium range models not showing much in the way of downstream blocking or buckling of the Polar jet, we should average out above normal on temperatures in the Wednesday through Friday forecast period. && .AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon) ISSUED AT 1132 AM CST SAT NOV 29 2014 Area of MVFR ceilings continues to advect northeast across east central Illinois and is about to move into KCMI. HRRR guidance suggests it should stay there much of the afternoon. Trajectories of the cloud deck indicate that KDEC will be on the western edge and would not be surprised to see a couple hours of ceilings below 3000 feet there. Otherwise, gusty south winds of 20-25 knots will settle down late afternoon, but most areas will see the winds stay above 10 knots through the night. A sharp cold front will move in from the northwest Sunday morning, with an area of MVFR ceilings likely behind it as well as increasing northwest winds. Right now, the TAFs only have the front through KPIA before the end of the forecast period, but areas from KSPI-KBMI may see the winds switching toward 18Z. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Geelhart SHORT TERM...Smith LONG TERM...Smith AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1026 AM CST SAT NOV 29 2014 .SHORT TERM... 338 AM CST MAIN FORECAST CONCERNS/CHALLENGES ARE WITH POSSIBLE STRATUS AND HIGH TEMPS TODAY...CONTINUED WARMER TEMPS TONIGHT INTO SUNDAY WITH RAIN CHANCES BEFORE COLD RETURNS BY THE END OF THE PERIOD. QUIETER CONDITIONS IN PLACE EARLY THIS MORNING WHILE ONLY HIGH LEVEL CLOUD COVER STREAMS OVERHEAD...WITH ONLY PATCHY FOG BEING OBSERVED OVER NORTHERN ILLINOIS. AS STRONG WAA PERSISTS ACROSS THE REGION...SURFACE TEMPS ARE EITHER HOLDING NEARLY STEADY OR RISING SLIGHTLY...AND IS OCCURRING AS SURFACE WARM FRONT TO THE SOUTHWEST IS APPROACHING THE SOUTHERN CWA. TEMPS WILL LIKELY SLOWLY WARM OVER THE NEXT SEVERAL HOURS AS THIS FRONT CONTINUES TO LIFT NORTHEAST ACROSS THE CWA AND THERMAL AXIS SETTLES IN...SETTING THE STAGE FOR A MUCH MILDER DAY. HAVE MADE LITTLE TO NO CHANGES TO GOING FORECAST HIGH TEMPS IN THE 50S TODAY...BUT WITH STILL SOME CONCERNS THAT LOW LEVEL STRATUS COULD LIMIT WARMING IN SOME LOCATIONS. CURRENT MID/HIGH LEVEL CLOUD COVER WILL CONTINUE TO STREAM OVERHEAD THROUGH THE NEXT SEVERAL HOURS AND PROVIDE PARTLY CLOUDY SKIES EARLY THIS MORNING...BUT AS WARM FRONT LIFTS NORTH...STRATUS WILL TRY TO DEVELOP ACROSS THE REGION. LOOKING UPSTREAM...LITTLE IF ANY STRATUS CURRENTLY IN PLACE...BUT ONCE AGAIN GUIDANCE STILL TRYING TO INDICATE THAT LOW STRATUS WILL DEVELOP BY MID TO LATE MORNING. CURRENT THINKING IS THAT DEVELOPMENT WILL OCCUR LATER THIS MORNING BUT WITH THE BETTER AXIS OF MORE SOLID CLOUD COVER STAYING TO THE SOUTHEAST OF THE CWA...WITH AREAS IN NORTHWEST INDIANA POSSIBLY GETTING INTO MORE PARTLY SUNNY SKIES. WITH ONLY PARTLY CLOUDY SKIES THEN EXPECTED INTO THE AFTERNOON...SEE NO REASON WHY MOST AREAS WILL NOT SEE THESE WARMER TEMPS. TONIGHT APPEARS TO BE ANOTHER PERIOD WITH A NONDIURNAL TREND LIKELY...WITH MILD CONDITIONS STILL IN PLACE. INCREASING MOISTURE AND LIFT SHOULD ALLOW FOR CLOUDIER SKIES AS WELL AS THE POSSIBILITY FOR PATCHY LIGHT DRIZZLE...MAINLY FOR EAST CENTRAL ILLINOIS AND NORTHWEST INDIANA. MILDER CONDITIONS ONCE AGAIN POSSIBLE FOR THE SOUTHEAST CWA SUNDAY MORNING AS PROGRESSING SURFACE LOW SHIFTS EAST ACROSS THE GREAT LAKES REGION OUT AHEAD OF APPROACHING UPPER LEVEL TROUGH...AND SURFACE COLD FRONT SURGES SOUTHEAST TOWARDS THE CWA. LIGHT RAIN WILL BE POSSIBLE OVER THE SOUTHEAST CWA SUNDAY MORNING INTO EARLY SUNDAY AFTERNOON AS THE COLD FRONT PUSHES THROUGH THE CWA DURING THIS TIME. EXPECT TEMPS TO BE BACK IN THE 20S ACROSS NORTHERN ILLINOIS BY MID AFTERNOON WITH THIS TREND CONTINUING FOR THE REMAINING CWA...AS BELOW NORMAL TEMPS RETURN SUNDAY NIGHT INTO MONDAY. RODRIGUEZ && .LONG TERM... 338 AM CST DRY CONDITIONS WILL START THE PERIOD WITH SOME SLIGHT WARMING ANTICIPATED...AS BACKING FLOW WILL ALLOW FOR A RETURN OF A WARMER AIRMASS. EXPECT HIGH TEMPS BACK IN THE UPPER 30S WEDNESDAY AND THURSDAY...BUT WITH CHANCES FOR PRECIP RETURNING BY THURSDAY. STILL SOME DIFFERENCES WITH REGARDS TO TIMING OF THIS SYSTEM AS WELL AS THERMAL PROFILES. BOTH OF THESE DIFFERENCE WILL LIKELY PLAY INTO PRECIP TYPE DURING THIS TIME...WITH A WINTRY MIX APPEARING POSSIBLE AT THIS TIME. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * SOUTH WINDS WITH GUSTS BETWEEN 20-24KT. * POSSIBLE MVFR CLOUDS/CIGS DEVELOPING TOWARD MIDDAY AND POTENTIALLY CONTINUING THROUGH THE AFTERNOON. * PATCHY DRIZZLE DEVELOPING LATE TONIGHT. MDB //DISCUSSION...UPDATED 16Z... STILL MONITORING STRATOCU POTENTIAL THIS MORNING. RECENT AIRCRAFT SOUNDINGS FROM MDW SHOW GOOD LOW LEVEL MOISTURE SUGGESTIVE OF CLOUD DEVELOPMENT. BETWEEN THE SOUNDINGS AND CURRENT TEMP-DEWPOINT SPREADS EXPECT THAT CLOUDS WOULD FORM AT OR JUST BELOW 2000 FT WITH THE MAIN QUESTION BEING WHETHER THEY WILL FORM OR NOT. HAVE PUSHED TIMING OF SCT MVFR LEVEL CLOUDS TO 17Z WHICH IS A MORE CLIMATOLOGICAL LY FAVORED TIME ANYWAY. WOULD EXPECT THAT A FEW HOUR PERIOD OF BKN MVFR CIGS WOULD OCCUR BEFORE SCATTERING...WITH RECENT NEAR TERM FORECAST SOUNDINGS ALSO SUPPORTIVE OF THIS. SO AM FAIRLY CONFIDENT IN DEVELOPMENT BUT LESS CONFIDENT IN BROKEN COVERAGE. OTHERWISE...STILL WATCHING ESTABLISHED STRATUS TO THE SOUTH WHICH COULD BE NEARBY BY 22Z OR SO. MDB FROM 12Z... IR IMAGERY CONTINUES TO SHOW CONSIDERABLE HIGH BASED CLOUDS ACROSS THE REGION...HOWEVER THE FOCUS IS ON THE STRATUS DECK OF CLOUDS QUICKLY DEVELOPING ACROSS FAR WESTERN KY/EASTERN ARKANSAS. BASED ON GUIDANCE...THIS STRATUS LAYER WILL CONTINUE TO ADVANCE NORTH AND GROW IN COVERAGE. IT APPEARS THAT THE STRATUS LAYER WILL ARRIVE AT TAF SITES MIDDAY...AS A WARM FRONT LIFTS NORTH. THE CONCERN IS THAT THE STRATUS LAYER COULD LINGER INTO THE AFTERNOON/EARLY EVE HOURS...WHICH WOULD RESULT IN HOLDING ONTO THE MVFR CIGS LONGER. WINDS WILL INCREASE LATE MORNING WITH GUSTS DEVELOPING TO NEAR 24KT...BUT COULD BE DIMINISHED WITH THE STRATUS LAYER LATER. OVERNIGHT PATCHY DRIZZLE IS EXPECTED TO DEVELOP ACROSS CENTRAL IL/IN...AND COULD SLIDE NORTH TOWARDS THE TAF SITES. GIVEN THE INCREASED LLVL MOISTURE...CIGS COULD RETURN TO MVFR CONDS THRU DAYBREAK SUN. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 16Z... * HIGH CONFIDENCE IN WIND FORECAST. * MEDIUM CONFIDENCE IN SCT MVFR CLOUDS DEVELOPING TOWARD MIDDAY ...LOW-MEDIUM CONFIDENCE IN BECOMING BROKEN AND DURATION OF BROKEN COVERAGE IF THEY DO. * LOW CONFIDENCE IN PATCHY DRIZZLE DEVELOPING LATE TONIGHT. MDB //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...MAINLY VFR. MONDAY...VFR. NORTHWEST WINDS BECOMING NORTH BY EVENING. TUESDAY...VFR. SOUTH WINDS. WEDNESDAY...VFR. WEST WINDS. THURSDAY...CHANCE OF RAIN AND SNOW. EAST WINDS. FRIDAY...CHANCE OF RAIN OR SNOW BEACHLER && .MARINE... 243 AM CST HELD ONTO THE SMALL CRAFT ADVISORY FOR TODAY THROUGH THIS EVENING...ALTHOUGH IT APPEARS TO BE MARGINAL CONDITIONS AND COULD SEE SOUTH WINDS MAINLY HOVERING BETWEEN 20-25KT. HIGH PRESSURE HAS MOVED EAST ALONG THE EASTERN SEABOARD THIS MORNING...AND WILL CONTINUE TO PUSH EAST ACROSS THE WESTERN ATLANTIC. MEANWHILE A TROUGH OF LOW PRESSURE CENTERED OVER THE DAKOTAS IS EXPECTED TO DEEPEN AS IT LIFTS NORTHEAST ACROSS NORTHERN MINNESOTA THIS EVENING. A WARM FRONTAL BOUNDARY EXTENDS EAST FROM THIS LOW PRESSURE SYSTEM...AND WILL LIFT NORTH ACROSS THE SOUTHERN HALF OF LAKE MICHIGAN THIS EVENING. WITH MUCH WARMER AIR LIFTING NORTH ACROSS THE LAKE IT IS POSSIBLE THAT MIXING THE HIGHER WINDS TO THE SURFACE MAY BE A BIT OF A CHALLENGE LATER THIS EVENING. THE LOW WILL CONTINUE TO MOVE NORTHEAST AND DEEPEN SUNDAY MORNING...WHILE A TRAILING COLD FRONT APPROACHES LAKE MICHIGAN SUNDAY MID-MORNING. A STRONG RIDGE OF HIGH PRESSURE WILL BEGIN TO SLIDE SOUTH FROM THE CANADIAN ROCKIES SUNDAY. AS THE HIGH PRESSURE BUILDS EAST...THE GRADIENT MAY INCREASE ENOUGH LATE SUNDAY/EARLY MONDAY TO PRODUCE WINDS TO 30KT OR POSSIBLY A FEW GALE FORCE GUSTS. HIGH PRESSURE THEN BRINGS LIGHTER WINDS TO THE LAKE MONDAY MIDDAY. THEN THE HIGH PRESSURE QUICKLY SHIFTS EAST MONDAY NIGHT...WITH WINDS TURNING SOUTH/SOUTHWEST. ANOTHER LOW PRESSURE SYSTEM IS EXPECTED TO DEVELOP TUESDAY MORNING ACROSS THE CENTRAL PLAINS. BETWEEN THE RIDGE AND TROUGH THE GRADIENT OVER THE LAKE WILL QUICKLY INCREASE AND COULD PRODUCE A PERIOD OF GALE FORCE WINDS TUESDAY AFTERNOON. BEACHLER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 10 PM SATURDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 956 AM CST Sat Nov 29 2014 .UPDATE... ISSUED AT 956 AM CST SAT NOV 29 2014 Area of low clouds has been spreading northeast out of the lower Ohio Valley this morning and was up to about I-70. Latest HRRR guidance continues to suggest this overspreading much of the CWA east of highway 51 into early afternoon, while areas further west primarily deal with a steady stream of cirrus clouds from the central Plains. Southerly winds already gusting 20-30 mph in areas east of the Illinois River and that will continue into the afternoon, boosting temperatures well into the 50s over the CWA. Have sent some updated zones/grids to tweak the cloud trends for today, and also to sharpen up the temperature trends for Sunday and Sunday night with the strong cold front. && .SHORT TERM...(Today) ISSUED AT 250 AM CST SAT NOV 29 2014 Southerly winds have prevailed through the night bringing mild conditions, at least compared to what occurred the past few mornings across central through southeast Illinois. The persistent southerly flow has resulted in a marked increase in the low level cloud cover over parts of Arkansas this morning with a north- northeast trajectory. Forecast soundings have indicated an increase in low level moisture for the past several runs which is being validated now over the lower Mississippi Valley. The last several runs of the HRRR model has brought the clouds northeast into about the eastern half of the forecast area by early this afternoon. Surface dew points over extreme southwest Missouri have risen into the mid and upper 40s early this morning and expect the persistent 1000-850 mb theta-e advection and moisture transport to bring the higher dew points and clouds northeast into our area later today. Despite the increase in clouds, temperatures are expected to warm into the low to mid 50s north to the upper 50s, possibly 60 degrees over parts of southwest Illinois this afternoon. Models for the past several days have hinted at some light QPF over parts of southeast Illinois with the significant moisture transport into our area. However, not seeing much in the way of lift with forecast soundings showing only the low level moisture trapped beneath a strengthening inversion today and tonight. Seems to be more of a setup for very light rain or drizzle over parts of southeast and east central Illinois and later this afternoon and tonight. && .LONG TERM...(Tonight through Friday) ISSUED AT 250 AM CST SAT NOV 29 2014 One more mild day across our area on Sunday before a strong cold front and associated 1047 mb high settles across the lower Great Lakes Sunday night and spends a few days early next week, before slight warmer weather returns for the balance of the forecast period. The strong Polar cold front looks on track for mainly Sunday afternoon along with light rain or drizzle chances just ahead and behind the frontal boundary. Best chances appear to be over the eastern half of the forecast area, mainly east of I-55, Sunday afternoon. Other than the low level moisture trapped beneath the rather strong inversion, not much moisture above, so looking more for drizzle or some very light rain Sunday afternoon into Sunday night. As the colder air settles south, there may be a brief period of some very light freezing rain or drizzle mainly over the I-70 corridor late Sunday night into the Monday morning commute. There may be some very light ice accumulations over extreme southeast Illinois just in time for the return to work and school Monday morning. Cold and dry conditions expected to settle over our area for Monday through Wednesday. We may see some lingering light precip Monday morning over the far southeast counties, but the front should get shunted well south of our area by Monday afternoon and evening ushering in some rather chilly temperatures again across the entire area Monday night. Lows will dip into the 10 to 15 degree range over the north half of the forecast area Tuesday morning with low to mid 20s common south. Quiet but chilly temperatures will be the story through Wednesday morning before we see a gradual moderating trend starting Wednesday afternoon as the upper flow becomes more zonal over the lower 48. Southerly return flow develops ahead of the next shortwave on Thursday bringing in warming temperatures but also chances for precipitation mainly from Wednesday night through Friday as a series of weak impulse translate east in the zonal flow across the center of the country. With the flow deamplifying during this period, we are seeing some timing differences with respect to the sensible weather associated with these fast moving and relatively weak waves, especially towards the end of the week. However, with a zonal flow pattern seen over western Canada and medium range models not showing much in the way of downstream blocking or buckling of the Polar jet, we should average out above normal on temperatures in the Wednesday through Friday forecast period. && .AVIATION...(For the 12Z TAFS through 12Z Sunday morning) ISSUED AT 530 AM CST SAT NOV 29 2014 Scattered to broken high cirrus has advected over the TAF sites and should remain over the area through most of the TAF period. However, in response to some warm air and moisture advection from the south, lower MVFR clouds are advecting northward toward the parts of IL. NAM low level RH fields and cloud forecast timing from the HRRR model suggest that most of the lower clouds will remain in the south and eastern parts of the state, so should only effect CMI this afternoon. So, will have scattered lower clouds at all sites this morning and afternoon, but have a 4hr TEMPO group at CMI for broken cigs this afternoon. The lower clouds will dissipate early this evening, but cirrus will remain tonight. Winds will be southerly through the period with gusts up to 25kts possible during the daytime hours. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Geelhart SHORT TERM...Smith LONG TERM...Smith AVIATION...Auten
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
552 AM CST SAT NOV 29 2014 .SHORT TERM... 338 AM CST MAIN FORECAST CONCERNS/CHALLENGES ARE WITH POSSIBLE STRATUS AND HIGH TEMPS TODAY...CONTINUED WARMER TEMPS TONIGHT INTO SUNDAY WITH RAIN CHANCES BEFORE COLD RETURNS BY THE END OF THE PERIOD. QUIETER CONDITIONS IN PLACE EARLY THIS MORNING WHILE ONLY HIGH LEVEL CLOUD COVER STREAMS OVERHEAD...WITH ONLY PATCHY FOG BEING OBSERVED OVER NORTHERN ILLINOIS. AS STRONG WAA PERSISTS ACROSS THE REGION...SURFACE TEMPS ARE EITHER HOLDING NEARLY STEADY OR RISING SLIGHTLY...AND IS OCCURRING AS SURFACE WARM FRONT TO THE SOUTHWEST IS APPROACHING THE SOUTHERN CWA. TEMPS WILL LIKELY SLOWLY WARM OVER THE NEXT SEVERAL HOURS AS THIS FRONT CONTINUES TO LIFT NORTHEAST ACROSS THE CWA AND THERMAL AXIS SETTLES IN...SETTING THE STAGE FOR A MUCH MILDER DAY. HAVE MADE LITTLE TO NO CHANGES TO GOING FORECAST HIGH TEMPS IN THE 50S TODAY...BUT WITH STILL SOME CONCERNS THAT LOW LEVEL STRATUS COULD LIMIT WARMING IN SOME LOCATIONS. CURRENT MID/HIGH LEVEL CLOUD COVER WILL CONTINUE TO STREAM OVERHEAD THROUGH THE NEXT SEVERAL HOURS AND PROVIDE PARTLY CLOUDY SKIES EARLY THIS MORNING...BUT AS WARM FRONT LIFTS NORTH...STRATUS WILL TRY TO DEVELOP ACROSS THE REGION. LOOKING UPSTREAM...LITTLE IF ANY STRATUS CURRENTLY IN PLACE...BUT ONCE AGAIN GUIDANCE STILL TRYING TO INDICATE THAT LOW STRATUS WILL DEVELOP BY MID TO LATE MORNING. CURRENT THINKING IS THAT DEVELOPMENT WILL OCCUR LATER THIS MORNING BUT WITH THE BETTER AXIS OF MORE SOLID CLOUD COVER STAYING TO THE SOUTHEAST OF THE CWA...WITH AREAS IN NORTHWEST INDIANA POSSIBLY GETTING INTO MORE PARTLY SUNNY SKIES. WITH ONLY PARTLY CLOUDY SKIES THEN EXPECTED INTO THE AFTERNOON...SEE NO REASON WHY MOST AREAS WILL NOT SEE THESE WARMER TEMPS. TONIGHT APPEARS TO BE ANOTHER PERIOD WITH A NONDIURNAL TREND LIKELY...WITH MILD CONDITIONS STILL IN PLACE. INCREASING MOISTURE AND LIFT SHOULD ALLOW FOR CLOUDIER SKIES AS WELL AS THE POSSIBILITY FOR PATCHY LIGHT DRIZZLE...MAINLY FOR EAST CENTRAL ILLINOIS AND NORTHWEST INDIANA. MILDER CONDITIONS ONCE AGAIN POSSIBLE FOR THE SOUTHEAST CWA SUNDAY MORNING AS PROGRESSING SURFACE LOW SHIFTS EAST ACROSS THE GREAT LAKES REGION OUT AHEAD OF APPROACHING UPPER LEVEL TROUGH...AND SURFACE COLD FRONT SURGES SOUTHEAST TOWARDS THE CWA. LIGHT RAIN WILL BE POSSIBLE OVER THE SOUTHEAST CWA SUNDAY MORNING INTO EARLY SUNDAY AFTERNOON AS THE COLD FRONT PUSHES THROUGH THE CWA DURING THIS TIME. EXPECT TEMPS TO BE BACK IN THE 20S ACROSS NORTHERN ILLINOIS BY MID AFTERNOON WITH THIS TREND CONTINUING FOR THE REMAINING CWA...AS BELOW NORMAL TEMPS RETURN SUNDAY NIGHT INTO MONDAY. RODRIGUEZ && .LONG TERM... 338 AM CST DRY CONDITIONS WILL START THE PERIOD WITH SOME SLIGHT WARMING ANTICIPATED...AS BACKING FLOW WILL ALLOW FOR A RETURN OF A WARMER AIRMASS. EXPECT HIGH TEMPS BACK IN THE UPPER 30S WEDNESDAY AND THURSDAY...BUT WITH CHANCES FOR PRECIP RETURNING BY THURSDAY. STILL SOME DIFFERENCES WITH REGARDS TO TIMING OF THIS SYSTEM AS WELL AS THERMAL PROFILES. BOTH OF THESE DIFFERENCE WILL LIKELY PLAY INTO PRECIP TYPE DURING THIS TIME...WITH A WINTRY MIX APPEARING POSSIBLE AT THIS TIME. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 12Z... * SOUTH WINDS INCREASING AFT 14Z WITH GUSTS BETWEEN 20-24KT. * POSSIBLE MVFR CIGS DEVELOPING MIDDAY WITH CIGS ARND 1500FT AGL. * PATCHY DRIZZLE DEVELOPING LATE TONIGHT. BEACHLER //DISCUSSION...UPDATED 12Z... IR IMAGERY CONTINUES TO SHOW CONSIDERABLE HIGH BASED CLOUDS ACROSS THE REGION...HOWEVER THE FOCUS IS ON THE STRATUS DECK OF CLOUDS QUICKLY DEVELOPING ACROSS FAR WESTERN KY/EASTERN ARKANSAS. BASED ON GUIDANCE...THIS STRATUS LAYER WILL CONTINUE TO ADVANCE NORTH AND GROW IN COVERAGE. IT APPEARS THAT THE STRATUS LAYER WILL ARRIVE AT TAF SITES MIDDAY...AS A WARM FRONT LIFTS NORTH. THE CONCERN IS THAT THE STRATUS LAYER COULD LINGER INTO THE AFTERNOON/EARLY EVE HOURS...WHICH WOULD RESULT IN HOLDING ONTO THE MVFR CIGS LONGER. WINDS WILL INCREASE LATE MORNING WITH GUSTS DEVELOPING TO NEAR 24KT...BUT COULD BE DIMINISHED WITH THE STRATUS LAYER LATER. OVERNIGHT PATCHY DRIZZLE IS EXPECTED TO DEVELOP ACROSS CENTRAL IL/IN...AND COULD SLIDE NORTH TOWARDS THE TAF SITES. GIVEN THE INCREASED LLVL MOISTURE...CIGS COULD RETURN TO MVFR CONDS THRU DAYBREAK SUN. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 12Z... * HIGH CONFIDENCE IN WIND DIR/SPEED...MEDIUM/HIGH CONFIDENCE IN TIMING/INTENSITY OF GUSTS. * MEDIUM/HIGH CONFIDENCE IN CIGS FORECAST...ALONG WITH MVFR CIGS DEVELOPING. * HIGH CONFIDENCE IN PATCHY DRIZZLE DEVELOPING LATE TONIGHT. BEACHLER //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...MAINLY VFR. MONDAY...VFR. NORTHWEST WINDS BECOMING NORTH BY EVENING. TUESDAY...VFR. SOUTH WINDS. WEDNESDAY...VFR. WEST WINDS. THURSDAY...CHANCE OF RAIN AND SNOW. EAST WINDS. FRIDAY...CHANCE OF RAIN OR SNOW BEACHLER && .MARINE... 243 AM CST HELD ONTO THE SMALL CRAFT ADVISORY FOR TODAY THROUGH THIS EVENING...ALTHOUGH IT APPEARS TO BE MARGINAL CONDITIONS AND COULD SEE SOUTH WINDS MAINLY HOVERING BETWEEN 20-25KT. HIGH PRESSURE HAS MOVED EAST ALONG THE EASTERN SEABOARD THIS MORNING...AND WILL CONTINUE TO PUSH EAST ACROSS THE WESTERN ATLANTIC. MEANWHILE A TROUGH OF LOW PRESSURE CENTERED OVER THE DAKOTAS IS EXPECTED TO DEEPEN AS IT LIFTS NORTHEAST ACROSS NORTHERN MINNESOTA THIS EVENING. A WARM FRONTAL BOUNDARY EXTENDS EAST FROM THIS LOW PRESSURE SYSTEM...AND WILL LIFT NORTH ACROSS THE SOUTHERN HALF OF LAKE MICHIGAN THIS EVENING. WITH MUCH WARMER AIR LIFTING NORTH ACROSS THE LAKE IT IS POSSIBLE THAT MIXING THE HIGHER WINDS TO THE SURFACE MAY BE A BIT OF A CHALLENGE LATER THIS EVENING. THE LOW WILL CONTINUE TO MOVE NORTHEAST AND DEEPEN SUNDAY MORNING...WHILE A TRAILING COLD FRONT APPROACHES LAKE MICHIGAN SUNDAY MID-MORNING. A STRONG RIDGE OF HIGH PRESSURE WILL BEGIN TO SLIDE SOUTH FROM THE CANADIAN ROCKIES SUNDAY. AS THE HIGH PRESSURE BUILDS EAST...THE GRADIENT MAY INCREASE ENOUGH LATE SUNDAY/EARLY MONDAY TO PRODUCE WINDS TO 30KT OR POSSIBLY A FEW GALE FORCE GUSTS. HIGH PRESSURE THEN BRINGS LIGHTER WINDS TO THE LAKE MONDAY MIDDAY. THEN THE HIGH PRESSURE QUICKLY SHIFTS EAST MONDAY NIGHT...WITH WINDS TURNING SOUTH/SOUTHWEST. ANOTHER LOW PRESSURE SYSTEM IS EXPECTED TO DEVELOP TUESDAY MORNING ACROSS THE CENTRAL PLAINS. BETWEEN THE RIDGE AND TROUGH THE GRADIENT OVER THE LAKE WILL QUICKLY INCREASE AND COULD PRODUCE A PERIOD OF GALE FORCE WINDS TUESDAY AFTERNOON. BEACHLER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 10 PM SATURDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 530 AM CST Sat Nov 29 2014 .SHORT TERM...(Today) ISSUED AT 250 AM CST SAT NOV 29 2014 Southerly winds have prevailed through the night bringing mild conditions, at least compared to what occurred the past few mornings across central through southeast Illinois. The persistent southerly flow has resulted in a marked increase in the low level cloud cover over parts of Arkansas this morning with a north- northeast trajectory. Forecast soundings have indicated an increase in low level moisture for the past several runs which is being validated now over the lower Mississippi Valley. The last several runs of the HRRR model has brought the clouds northeast into about the eastern half of the forecast area by early this afternoon. Surface dew points over extreme southwest Missouri have risen into the mid and upper 40s early this morning and expect the persistent 1000-850 mb theta-e advection and moisture transport to bring the higher dew points and clouds northeast into our area later today. Despite the increase in clouds, temperatures are expected to warm into the low to mid 50s north to the upper 50s, possibly 60 degrees over parts of southwest Illinois this afternoon. Models for the past several days have hinted at some light QPF over parts of southeast Illinois with the significant moisture transport into our area. However, not seeing much in the way of lift with forecast soundings showing only the low level moisture trapped beneath a strengthening inversion today and tonight. Seems to be more of a setup for very light rain or drizzle over parts of southeast and east central Illinois and later this afternoon and tonight. && .LONG TERM...(Tonight through Friday) ISSUED AT 250 AM CST SAT NOV 29 2014 One more mild day across our area on Sunday before a strong cold front and associated 1047 mb high settles across the lower Great Lakes Sunday night and spends a few days early next week, before slight warmer weather returns for the balance of the forecast period. The strong Polar cold front looks on track for mainly Sunday afternoon along with light rain or drizzle chances just ahead and behind the frontal boundary. Best chances appear to be over the eastern half of the forecast area, mainly east of I-55, Sunday afternoon. Other than the low level moisture trapped beneath the rather strong inversion, not much moisture above, so looking more for drizzle or some very light rain Sunday afternoon into Sunday night. As the colder air settles south, there may be a brief period of some very light freezing rain or drizzle mainly over the I-70 corridor late Sunday night into the Monday morning commute. There may be some very light ice accumulations over extreme southeast Illinois just in time for the return to work and school Monday morning. Cold and dry conditions expected to settle over our area for Monday through Wednesday. We may see some lingering light precip Monday morning over the far southeast counties, but the front should get shunted well south of our area by Monday afternoon and evening ushering in some rather chilly temperatures again across the entire area Monday night. Lows will dip into the 10 to 15 degree range over the north half of the forecast area Tuesday morning with low to mid 20s common south. Quiet but chilly temperatures will be the story through Wednesday morning before we see a gradual moderating trend starting Wednesday afternoon as the upper flow becomes more zonal over the lower 48. Southerly return flow develops ahead of the next shortwave on Thursday bringing in warming temperatures but also chances for precipitation mainly from Wednesday night through Friday as a series of weak impulse translate east in the zonal flow across the center of the country. With the flow deamplifying during this period, we are seeing some timing differences with respect to the sensible weather associated with these fast moving and relatively weak waves, especially towards the end of the week. However, with a zonal flow pattern seen over western Canada and medium range models not showing much in the way of downstream blocking or buckling of the Polar jet, we should average out above normal on temperatures in the Wednesday through Friday forecast period. && .AVIATION...(For the 12Z TAFS through 12Z Sunday morning) ISSUED AT 530 AM CST SAT NOV 29 2014 Scattered to broken high cirrus has advected over the TAF sites and should remain over the area through most of the TAF period. However, in response to some warm air and moisture advection from the south, lower MVFR clouds are advecting northward toward the parts of IL. NAM low level RH fields and cloud forecast timing from the HRRR model suggest that most of the lower clouds will remain in the south and eastern parts of the state, so should only effect CMI this afternoon. So, will have scattered lower clouds at all sites this morning and afternoon, but have a 4hr TEMPO group at CMI for broken cigs this afternoon. The lower clouds will dissipate early this evening, but cirrus will remain tonight. Winds will be southerly through the period with gusts up to 25kts possible during the daytime hours. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Smith LONG TERM...Smith AVIATION...Auten
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
310 AM CST SAT NOV 29 2014 .SHORT TERM... 300 PM CST THROUGH SUNDAY... A TEMPERATURE ROLLER COASTER RIDE OVER THE NEXT FEW DAYS IS THE MAIN FOCUS OF THE FORECAST. TONIGHT AND SATURDAY... W/V IMAGERY SHOWS THAT HIGHLY AMPLIFIED PATTERN THAT RESULTED IN ALL THE COLD AIR THE PAST FEW WEEKS IS RAPIDLY BEING REPLACED BY ZONAL MID AND UPPER FLOW. A VERY WARM AND DRY AIR MASS OVER THE CENTRAL PLAINS THIS MORNING WILL RAPIDLY BE ADVECTED INTO THE AREA TONIGHT INTO SATURDAY BY DECENT SOUTHWEST FLOW AT H85. IN ADDITION...A SFC WARM FRONTAL FEATURE IS ALSO BEGINNING THE PROCESS OF LIFTING WARMER AND MORE MOIST AIR NORTHWARD THIS AFTERNOON...WHICH RESULTED IN PATCHY LOW CLOUD DEVELOPMENT FOR A TIME. STILL SOME CONCERN FOR LIGHT QPF EARLY THIS EVENING IN THE FAR NORTH...WHICH IF ANY COULD REACH THE GROUND WOULD LIKELY BE IN THE FORM OF LIGHT SNOW OR PELLETS DUE TO WET BULB PROCESSES. THINK THE FOCUS WILL BE JUST NORTH OF THE CWA SO HAVE REMOVED SLIGHT POPS BUT WILL NEED TO MONITOR THIS. THE MODELS APPEAR TO BE STRUGGLING GREATLY WITH AMOUNT OF SNOW COVER ON THE GROUND OVER THE CWA...ESPECIALLY THE NAM AND RAP. EXPECTING THAT SKIES WILL TREND TO PARTLY CLOUDY TONIGHT...WHICH DESPITE STEADY SOUTHERLY WINDS...COULD SET THE STAGE FOR PATCHY GROUND FOG OVER STILL SNOW COVERED AREAS. TEMPERATURES ARE EXPECTED TO REMAIN STEADY OR SLOWLY RISE OVERNIGHT. THE SNOW COVER/CLOUD COVER ISSUE COMES TO A HEAD ON SATURDAY. LOOKING IN THE WARM SECTOR OF THE DEVELOPING HIGH PLAINS LOW TODAY...THERE IS LITTLE IN THE WAY OF CLOUD COVER. HOWEVER...MANY MODELS INSIST ON BREAKING OUT LOW CLOUDS/LOW LEVEL SATURATION. WITH A +12 TO +15C AIR MASS AT 850 MB MOVING INTO THE AREA...SUSPECT THAT MUCH OF THE GUIDANCE IS BIASED FAR TOO COLD TOMORROW. IT SEEMS THAT THE CANADIAN GLOBAL AND REGIONAL MODELS...WHICH TYPICALLY DO BETTER IN COOL SEASON WARM-UPS...HAVE A MUCH BETTER HANDLE ON LIKELY LACK OF LOW LEVEL CLOUD COVER...WHICH CAN BE SEEN ON FORECAST SOUNDINGS. HAVE BUMPED UP TEMPERATURES IN THE LOW-MID 50S AREA WIDE...EXCEPT FOR NEAR 50 ALONG IMMEDIATE WI BORDER WHERE 2-4 INCHES OF SNOW DEPTH WERE REPORTED TODAY. HAVE CONSERVATIVELY LOWERED SKY COVER PERCENTAGE AS WELL...AS OTHER THAN SOME MID/HIGH CLOUDS...IT APPEARS A DECENT AMOUNT OF SUN COULD BE IN STORE. SATURDAY NIGHT AND SUNDAY... A VERY MILD SATURDAY NIGHT WILL ALLOW FOR A ANOTHER WARM SUNDAY FOR PARTS OF THE CWA. HOWEVER...THERE WILL BE AN ARCTIC FRONT SURGING SOUTHWARD AHEAD OF EXPANSIVE AND STRONG HIGH PRESSURE OVER THE NORTHERN PLAINS. TIMING OF THIS FRONT IS KEY AND NOW THINK IT WILL BE INTO THE NORTHERN CWA BY LATE AM/MID DAY...CAPPING HIGHS NEAR 40/LOW 40S THERE. FAR SOUTHERN CWA COULD CONCEIVABLY APPROACH 60 DEGREES GIVEN MORE TIME TO WARM UP AHEAD OF THE FRONT. UPPER FORCING IS NOT IMPRESSIVE WITH THE FRONT BUT LOW LEVEL MOISTURE CONVERGENCE AND DECENT LOW/MID F-GEN DUE TO QUICKLY TIGHTENING THERMAL GRADIENT COULD BE ENOUGH FOR ISOLATED/WIDELY SCT`D RAIN SHOWERS MAINLY IN AFTERNOON IN SOUTHEAST 1/3 OF CWA. RC && .LONG TERM... 249 PM CST SUNDAY NIGHT THROUGH FRIDAY... LOW LEVEL ARCTIC AIR MASS WILL QUICKLY SPILL SOUTHWARD SUNDAY NIGHT AS UPPER TROUGH BRIEFLY DIGS ACROSS NORTHERN TIER AND STRONG HIGH PRESSURE SPREADS SOUTHEAST. AIR MASS LOOKS FAIRLY DRY OVER THE LAKE...BUT LAKE EFFECT PARAMETERS ARE MARGINALLY FAVORABLE FOR SOME LAKE EFFECT SNOW SHOWERS SUNDAY NIGHT INTO MONDAY MORNING FOR THE SOUTHEAST TIP OF THE LAKE. TEMPERATURES WILL TUMBLE INTO THE TEENS AND 20S BY MONDAY MORNING...WITH CONTINUED COLD ADVECTION RESULTING IN A WELL BELOW NORMAL START TO METEOROLOGICAL WINTER. HIGHS WILL LIKELY BE IN 20S CWA WIDE/IF NOT COLDER IN FAR NORTH...FOLLOWED BY A COLD NIGHT MONDAY NIGHT AS 1040 MB+ HIGH PRESSURE MOVES OVERHEAD. PATTERN WILL QUICKLY TURN ZONAL AGAIN BUT COLD AIR REMAINING JUST TO NORTH SHOULD KEEP TEMPERATURES ON THE COOLER SIDE THROUGH MID WEEK. BIG TIMING DIFFERENCES IN THE LATE WEEK TIMEFRAME WITH ECMWF AND GFS/GEFS...AS ECMWF KEEPS DRY/COOL HIGH LOCKED IN TIL THURSDAY MORNING...WHILE GFS BREAKS OUT PRECIP ALONG BAROCLINIC ZONE WEDNESDAY NIGHT INTO THURSDAY. HAVE MAINTAINED LOW GUIDANCE BLEND POPS BUT CONFIDENCE IS FAIRLY LOW IN TEMPS AND SENSIBLE WX WEDS-THURSDAY...THOUGH A MILD PERIOD DOES LOOK TO BE IN THE CARDS LATE NEXT WORK WEEK INTO THE WEEKEND. RC && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * POSSIBLE MVFR VSBYS WITH PATCHY FOG OVERNIGHT/PRE-DAWN. * CHANCE OF MVFR REDEVELOPING AFT 00Z SUN. * SOUTH WINDS ARND 5-7KT...INCREASING WITH GUSTS TO 20-24KT LATE MORNING THRU AFTN. BEACHLER //DISCUSSION...UPDATED 06Z... IR IMAGERY SHOWS CONSIDERABLE MID/HIGH BASED CLOUDS SLIDING EAST/SOUTHEAST ACROSS THE REGION. A WARM FRONTAL BOUNDARY WAS BEGINNING TO LIFT NORTH...HOWEVER IT IS LIKELY NOT GOING TO ARRIVE ACROSS THE TAF SITES UNTIL LATER THIS MORNING. PRIOR TO THIS WINDS WILL REMAIN SOUTHERLY WITH PATCHY FOG DEVELOPING. IT APPEARS THE BEST CHANCE FOR MVFR VSBYS FROM FOG WILL BE WEST OF ORD/MDW...SO HAVE MAINTAINED RFD/DPA SEEING ARND 3SM VSBYS OVERNIGHT. BUT CONFIDENCE IN REDUCTIONS HAS BACKED OFF DUE TO THE CONTINUED WINDS KEEPING THINGS MIXED. GUIDANCE CONTINUES TO POINT TOWARDS DRY CONDS THRU DAYBREAK AND CONTINUE THRU THIS EVE. BETTER MIXING LATER THIS MORNING WILL LIKELY ALLOW GUSTY WINDS TO REDEVELOP BETWEEN 20-24KT FOR THE BULK OF THE DAY INTO EARLY THIS EVENING. THERE IS THE POTENTIAL THAT STRATUS CLOUDS MAY DEVELOP ALONG THE WARM FRONT...AND THIS COULD POSE A SIGNIFICANT CHANGE TO THE CURRENT VFR CONDS EXPECTED ACROSS THE TAF SITES LATER TODAY. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM CONFIDENCE IN FOG DEVELOPING...HIGH CONFIDENCE IN VFR CONDS FOR ORD/MDW WITH FOG REMAINING WEST. * MEDIUM CONFIDENCE IN WIND DIR/SPEED...HIGH CONFIDENCE IN GUSTS DEVELOPING. * MEDIUM/HIGH CONFIDENCE IN DRY CONDS. * MEDIUM CONFIDENCE IN CIGS FORECAST LATER TODAY. BEACHLER //OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z... SUNDAY...MVFR CIGS POSSIBLE. SOUTHWEST WINDS BECOMING NORTHWEST. MONDAY...VFR. NORTHWEST WINDS BECOMING NORTH BY EVENING. TUESDAY...VFR. SOUTH WINDS. WEDNESDAY...VFR. WEST WINDS. THURSDAY...CHANCE OF RAIN AND SNOW. EAST WINDS. MTF && .MARINE... 243 AM CST HELD ONTO THE SMALL CRAFT ADVISORY FOR TODAY THROUGH THIS EVENING...ALTHOUGH IT APPEARS TO BE MARGINAL CONDITIONS AND COULD SEE SOUTH WINDS MAINLY HOVERING BETWEEN 20-25KT. HIGH PRESSURE HAS MOVED EAST ALONG THE EASTERN SEABOARD THIS MORNING...AND WILL CONTINUE TO PUSH EAST ACROSS THE WESTERN ATLANTIC. MEANWHILE A TROUGH OF LOW PRESSURE CENTERED OVER THE DAKOTAS IS EXPECTED TO DEEPEN AS IT LIFTS NORTHEAST ACROSS NORTHERN MINNESOTA THIS EVENING. A WARM FRONTAL BOUNDARY EXTENDS EAST FROM THIS LOW PRESSURE SYSTEM...AND WILL LIFT NORTH ACROSS THE SOUTHERN HALF OF LAKE MICHIGAN THIS EVENING. WITH MUCH WARMER AIR LIFTING NORTH ACROSS THE LAKE IT IS POSSIBLE THAT MIXING THE HIGHER WINDS TO THE SURFACE MAY BE A BIT OF A CHALLENGE LATER THIS EVENING. THE LOW WILL CONTINUE TO MOVE NORTHEAST AND DEEPEN SUNDAY MORNING...WHILE A TRAILING COLD FRONT APPROACHES LAKE MICHIGAN SUNDAY MID-MORNING. A STRONG RIDGE OF HIGH PRESSURE WILL BEGIN TO SLIDE SOUTH FROM THE CANADIAN ROCKIES SUNDAY. AS THE HIGH PRESSURE BUILDS EAST...THE GRADIENT MAY INCREASE ENOUGH LATE SUNDAY/EARLY MONDAY TO PRODUCE WINDS TO 30KT OR POSSIBLY A FEW GALE FORCE GUSTS. HIGH PRESSURE THEN BRINGS LIGHTER WINDS TO THE LAKE MONDAY MIDDAY. THEN THE HIGH PRESSURE QUICKLY SHIFTS EAST MONDAY NIGHT...WITH WINDS TURNING SOUTH/SOUTHWEST. ANOTHER LOW PRESSURE SYSTEM IS EXPECTED TO DEVELOP TUESDAY MORNING ACROSS THE CENTRAL PLAINS. BETWEEN THE RIDGE AND TROUGH THE GRADIENT OVER THE LAKE WILL QUICKLY INCREASE AND COULD PRODUCE A PERIOD OF GALE FORCE WINDS TUESDAY AFTERNOON. BEACHLER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 10 PM SATURDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 300 AM CST Sat Nov 29 2014 .SHORT TERM...(Today) ISSUED AT 250 AM CST SAT NOV 29 2014 Southerly winds have prevailed through the night bringing mild conditions, at least compared to what occurred the past few mornings across central through southeast Illinois. The persistent southerly flow has resulted in a marked increase in the low level cloud cover over parts of Arkansas this morning with a north- northeast trajectory. Forecast soundings have indicated an increase in low level moisture for the past several runs which is being validated now over the lower Mississippi Valley. The last several runs of the HRRR model has brought the clouds northeast into about the eastern half of the forecast area by early this afternoon. Surface dew points over extreme southwest Missouri have risen into the mid and upper 40s early this morning and expect the persistent 1000-850 mb theta-e advection and moisture transport to bring the higher dew points and clouds northeast into our area later today. Despite the increase in clouds, temperatures are expected to warm into the low to mid 50s north to the upper 50s, possibly 60 degrees over parts of southwest Illinois this afternoon. Models for the past several days have hinted at some light QPF over parts of southeast Illinois with the significant moisture transport into our area. However, not seeing much in the way of lift with forecast soundings showing only the low level moisture trapped beneath a strengthening inversion today and tonight. Seems to be more of a setup for very light rain or drizzle over parts of southeast and east central Illinois and later this afternoon and tonight. && .LONG TERM...(Tonight through Friday) ISSUED AT 250 AM CST SAT NOV 29 2014 One more mild day across our area on Sunday before a strong cold front and associated 1047 mb high settles across the lower Great Lakes Sunday night and spends a few days early next week, before slight warmer weather returns for the balance of the forecast period. The strong Polar cold front looks on track for mainly Sunday afternoon along with light rain or drizzle chances just ahead and behind the frontal boundary. Best chances appear to be over the eastern half of the forecast area, mainly east of I-55, Sunday afternoon. Other than the low level moisture trapped beneath the rather strong inversion, not much moisture above, so looking more for drizzle or some very light rain Sunday afternoon into Sunday night. As the colder air settles south, there may be a brief period of some very light freezing rain or drizzle mainly over the I-70 corridor late Sunday night into the Monday morning commute. There may be some very light ice accumulations over extreme southeast Illinois just in time for the return to work and school Monday morning. Cold and dry conditions expected to settle over our area for Monday through Wednesday. We may see some lingering light precip Monday morning over the far southeast counties, but the front should get shunted well south of our area by Monday afternoon and evening ushering in some rather chilly temperatures again across the entire area Monday night. Lows will dip into the 10 to 15 degree range over the north half of the forecast area Tuesday morning with low to mid 20s common south. Quiet but chilly temperatures will be the story through Wednesday morning before we see a gradual moderating trend starting Wednesday afternoon as the upper flow becomes more zonal over the lower 48. Southerly return flow develops ahead of the next shortwave on Thursday bringing in warming temperatures but also chances for precipitation mainly from Wednesday night through Friday as a series of weak impulse translate east in the zonal flow across the center of the country. With the flow deamplifying during this period, we are seeing some timing differences with respect to the sensible weather associated with these fast moving and relatively weak waves, especially towards the end of the week. However, with a zonal flow pattern seen over western Canada and medium range models not showing much in the way of downstream blocking or buckling of the Polar jet, we should average out above normal on temperatures in the Wednesday through Friday forecast period. && .AVIATION...(For the 06Z TAFS through 06Z Saturday night) ISSUED AT 1147 PM CST FRI NOV 28 2014 VFR conditions across central/SE IL expected to deteriorate early Saturday morning as low level moisture overruns a warm frontal zone. Model forecast soundings indicate saturation down to surface in this scenario, but based TAFs more on typical MOS guidance values which look more likely. Went with MVFR cigs/vsby by 14Z with cloud cover becoming scattered after 19Z. Winds generally S10-15 kts. Gusts 20-25 kts during afternoon hours. Took low level wind shear out of TAFs for this update as winds sampled by area soundings have been a bit slower than previous model forecasts, meaning total wind shear below 2 kft AGL will struggle to reach 30 kts. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Smith LONG TERM...Smith AVIATION...Onton
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1117 PM CST FRI NOV 28 2014 .SYNOPSIS... ISSUED AT 318 PM CST FRI NOV 28 2014 NEARLY ZONAL FLOW ALOFT AND H85 WAA IS AIDING TO ADVECT A WARM FRONT INTO THE AREA TODAY. TEMPERATURES RANGE FROM THE LOWER TO MID 40S ACROSS THE SOUTHERN CWA...AND TO THE MID AND LOWER 30S ACROSS THE NORTHERN CWA. SATELLITE IMAGERY IS SHOWING THE SNOW PACK MELTING WITH THIS WAA. DEWPOINTS ARE RISING INTO THE UPPER 20S TO LOW 30S. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 318 PM CST FRI NOV 28 2014 MAIN FORECAST CONCERN FOR THE SHORT TERM FORECAST IS THE WARM FRONT MOVING INTO THE AREA TONIGHT BRINGING WITH IT A CHANCE OF FOG AND POSSIBLY LOW LEVEL CLOUDS. IT IS CLEAR THAT THE MODELS...ESPECIALLY THE NAM DO NOT HAVE A GOOD HANDLE ON BOUNDARY LAYER MOISTURE. THE NAM OVER DOES THE CURRENT SNOW COVER. WITH STRONG H85 WAA THE NAM POPS LOW LEVEL CLOUDS TONIGHT AND THROUGH MOST OF THE DAY. THE GFS HAS SOMETHING SIMILAR...BUT NOT AS BULLISH. A LOOK AT THE MODEL FIELDS AND OBSERVATIONS LEADS ME TO BELIEVE THAT THERE IS NOT A GOOD CHANCE FOR THE DEVELOPMENT OF LOW LEVEL CLOUDS...THERE IS NOT ENOUGH DEEP LAYER MOISTURE OR FORCING FOR CLOUD DEVELOPMENT. BELIEVE THAT THE MAIN THREAT WILL BE FOG DUE TO OVERRUNNING WARM AIR OVER A MELTING SNOW PACK. WINDS ARE FORECAST TO REMAIN AROUND 8-10KTS TONIGHT WHICH MAY INHIBIT FOG DEVELOPMENT. THIS WIND WILL MAKE FOG DEVELOPMENT PATCHY TONIGHT . HIGH LEVEL CLOUDS SHOULD CONTINUE TO ADVECT THROUGH THE AREA...ALSO INHIBITING THE DEVELOPMENT OF FOG OVER A LARGE AREA. SATURDAY LOOKS TO BE WARM WITH TEMPERATURES IN THE MID 40S TO LOW 50S SOUTH. DID NOT USE ANY OF THE NAM GUIDANCE FOR TEMP FORECASTS AS THE NAM KEEPS SNOW PACK AROUND A THUS LOWERS TEMPS. HIGH TEMPERATURES TODAY WERE UNDER DOWN AS H85 WAA DROVE TEMPS HIGHER. THE RUC HAD THE BEST HANDLE ON HIGHS AND TRENDS WITH TEMPS TODAY. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 318 PM CST FRI NOV 28 2014 SATURDAY NIGHT...COLD FRONT TO ARRIVE NORTHWEST CWA TOWARD DAYBREAK. PATCHY FOG POSSIBLE AHEAD OF FRONT BUT WITH AMERICAN MODELS VERIFYING TOO MOIST OVER BL AND ENOUGH OF GRADIENT PRE-FRONTAL FOR 5-10+ MPH WINDS AND TYPICALLY NOT FAVORED VEERING SOUTHWESTERLY DIRECTION I HAVE LEFT OUT ANY MENTION ATTIM. DECENT TEMP GRADIENT BY 12Z SUN WITH 20S FAR NORTHWEST CWA POST-FRONTAL CONTRAST TO UPPER 30S AND LOWER 40S FAR SOUTHEAST CWA. SUNDAY AND SUNDAY NIGHT...HIGHS ON SUNDAY TO OCCUR IN THE AM THROUGH MIDDAY AHEAD OF FRONTAL PASSAGE. FRONT IS ANTICIPATED TO BE EXITING FAR EAST/SOUTHEAST CWA BY MIDDAY. ENSUING COLD ADVECTION ON BRISK NORTHWEST WINDS 15 TO 30 MPH WILL RESULT IN FALLING TEMPS DESPITE DECREASING CLOUDS FOR AT LEAST PARTIAL PM SUNSHINE. SUNDAY NIGHT...CONTINUED CLEARING EARLY WITH CANADIAN HIGH AND ATTENDANT STRONG SUBSIDENCE BUILDING IN. LINGERING PRESSURE GRADIENT TO MAINTAIN ENOUGH WIND TO PREVENT COMPLETE BOTTOM OUT ON LOWS AND WITH LOSS OF SNOW COVER LEANED TOWARD WARMER SIDE OF GUIDANCE BLEND...WITH MAINLY TEENS FOR LOWS WITH SOME SINGLE DIGITS NORTHWEST CWA. THESE TEMPS COMBINED WITH WINDS WILL PRODUCE BITTER COLD WIND CHILLS IN SINGLE DIGITS ABOVE AND BELOW ZERO OVERNIGHT INTO EARLY MONDAY MORNING. MONDAY AND MONDAY NIGHT...DRY AND CONTINUED COLD WITH WELL BELOW NORMAL TEMPS AS CANADIAN HIGH BUILDS IN. HIGHS MONDAY IN THE TEENS AND 20S. LOWS MONDAY NIGHT IN SINGLE DIGITS TO AROUND 10 DEGS. IF ANY LONGER DURATION OF LIGHT OR CALM WINDS THEN LOWS MAY BE STILL 2-4 DEGS TOO WARM SOME LOCATIONS. TUESDAY AND TUESDAY NIGHT...CANADIAN HIGH WILL SHIFT EAST INTO THE OHIO VLY DURING THE DAY ON TUESDAY WITH STRENGTHENING RETURN FLOW USHERING IN WARMER AIR FOR REBOUND ON TEMPS INTO THE 30S FOR HIGHS MANY AREAS. CONTINUED SOUTHERLY WINDS TO KEEP LOWS MAINLY IN THE 20S TUESDAY NIGHT. WEDNESDAY THROUGH FRIDAY...MEDIUM RANGE MODELS SUPPORT A LIGHT PCPN EVENT AS EJECTING ENERGY FROM ROCKIES MEETS UP WITH INCREASING MOISTURE. CHALLENGE THOUGH IS MODELS CONTINUE TO VARY ON THE TIMING/PLACEMENT OF SURFACE AND UPPER FEATURES AND AS RESULT INSTEAD OF PLACING HIGHER POPS FOR WHAT IS LIKELY TO BE ONLY 12 HOUR EVENT AT BEST... HAVE PLACED SMALL POPS OVER 24+ HOUR PERIOD FOCUSING ON THURSDAY AND THURSDAY NIGHT ATTIM. PCPN TYPE APPEARS TO BE MAINLY RAIN BUT DEPENDING ON TIMING COULD BEGIN AS LIGHT WINTRY MIX IN SOME AREAS. TEMPS WILL CONTINUE MODERATING TO CLOSER TO NORMAL DURING THE PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1106 PM CST FRI NOV 28 2014 A STRONG WARM FRONT IN SOUTHERN IOWA WILL SWEEP NORTH OF ALL TERMINALS BY 15Z SATURDAY. THROUGH SUNRISE...SOME MVFR FOG IS POSSIBLE IN NORTHEAST IOWA...BUT AS WINDS INCREASE...THIS WILL BECOME LESS WIDESPREAD AND SHOULD BE A BRIEF OCCURRENCE AT CID AND DBQ...THUS A TEMPO FOR 4SM FOG IS INCLUDED VS A FM GROUP. OTHERWISE...ALL TAFS WILL SEE SOUTH WINDS OF 1O TO 20 KTS...AND VFR CIGS THROUGH SATURDAY. MODELS ARE WRONG...AND FORECAST CONSISTENTLY VERY LOW IFR AND EVEN MINIMUMS AT ALL SITES THROUGH THE PERIOD. WE ARE NOT GOING WITH THIS IDEA. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...GIBBS SHORT TERM...GIBBS LONG TERM...05 AVIATION...ERVIN
AREA FORECAST DISCUSSION
NWS TOPEKA KS
536 AM CST Sat Nov 29 2014 ...Update to aviation forecast discussion... .SHORT TERM...(Today and Tonight) Issued at 306 AM CST SAT NOV 29 2014 The main concern with this forecast period will be the potential for stratus and or haze developing over parts of eastern KS later this morning. At the surface there continues to be a decent pressure gradient across the area, although this gradient is weaker in north central KS. Southerly winds have contributed to an increase in moisture over eastern KS due to a fetch from Texas and eastern OK. It is this moisture that some of the models think will help form the stratus. What the models seem to be having trouble with is the high cirrus clouds that continue to overspread from the west. If these clouds were to break up or dissipate then radiational cooling could inhibit the stratus. The high level clouds and mixing have kept temps steady in the mid 40s to near 50. Given the continuous cirrus aloft and surface pressure gradient have not mentioned stratus or fog into the forecast. The most likely location for stratus will be along and east of the turnpike especially near I-35 where dew point depressions are already relatively low. Temperatures will also be tricky today if the stratus forms keeping some areas from getting out of the 50s according to some models. Not confident in this scenario therefore most locations should get well into the 60s and near 70 in central KS. Later tonight the strong cold front will continue pushing south through the central plains. Models agree it should arrive in northern KS around 09Z and the I-70 corridor by 12Z Sunday. Temperatures will fall behind the front which will set up a decent gradient in low temperatures. North central KS should drop to the upper 20s while east central KS stays in the upper 40s ahead of the front. A few models have indicated low level saturation coinciding with weak lift moving in behind the front, but at the moment remains north of the area through 12Z. .LONG TERM...(Sunday through Friday) Issued at 306 AM CST SAT NOV 29 2014 Strong cold front continues to move across eastern Kansas on Sunday morning and should be through the area by around the noon hour. Highs are a wide range, from near 30 in the north central to near 50 in the southeast, but as front comes through and temperatures drop, as well as the increase in wind speeds, apparent temperature values will make it feel like its in the teens to 20s. Models differ in amount of low level saturation with this front, and layer is quite shallow. However some guidance puts out a very low amount of QPF across the far eastern counties, and if front appears to be coming in with associated stratus may need to consider a very short window of light freezing drizzle for the east as the front comes through. Overnight lows drop into the teens, with winds slowly diminishing from north to south through the day on Monday. Wind chills for the morning commute Monday are currently forecast from around zero to negative single digits. Highs on Monday around 30 fall once again down into the teens overnight. Tuesday the cold high moves eastward as the next upper trof moves across the Northern Plains. Southerly flow returns at the surface and temperatures rise back to around 40. Model differences start to amplify beyond this forecast period, although seem to be in general agreement that next boundary to come southward into the state is not as cold and moderates quickly keeping high temperatures in the 40s. GFS starts rain chances as early as late Wednesday while EC is deeper but farther eastward with that system. Both draw moisture northward off the Gulf coast and have some lower end chance for rain on Thursday. Kept Friday dry with a short warmup between systems. && .AVIATION...(For the 12Z TAFs through 12Z Sunday Morning) Issued at 525 AM CST SAT NOV 29 2014 There is a very slight chance that a stratus deck forms over TOP/FOE later this morning as depicted by the NAM and SREF. Also, the areas that have cleared out over south central KS have already had fog develop which is the direction the HRRR has trended. This fog or haze could possibly affect MHK in the next few hours. All models indicate VFR conditions after 15Z. Confidence is low in these scenarios therefore did not include in the tafs. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Sanders LONG TERM...67 AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS JACKSON KY
111 PM EST SAT NOV 29 2014 .UPDATE... ISSUED AT 111 PM EST SAT NOV 29 2014 CURRENT SURFACE OBSERVATIONS ARE SHOWING THAT THE WIND IS STARTING TO PICK UP ACROSS THE AREA THIS AFTERNOON. CLOUD COVER HAS BEEN WIDE SPREAD ACROSS THE AREA. TEMPERATURES CONTINUE TO WARM INTO THE 50S WITH THE EXPECTED HIGHS IN THE MID 50S SEEMING LIKELY. THAT SAID...THE CLOUD COVER DID NEED TO BE TWEAKED TO ACCOUNT FOR IT HANGING AROUND...MOST LIKELY UNTIL THE FRONT FINALLY BEGINS ITS MARCH EASTWARD. WITH THIS IN MIND...WILL KEEP THE FORECAST GOING AND UPDATE THE ZFP WITH THE AFTERNOON PACKAGE ISSUANCE. UPDATE ISSUED AT 1001 AM EST SAT NOV 29 2014 CURRENT CONDITIONS ACROSS THE AREA TODAY FEATURE SOME MID AND UPPER LEVEL CLOUD COVER MOVING IN FROM THE WEST WHILE SOME LOWER LEVEL CLOUD COVER IN SOUTHERLY FLOW MOVES NORTH INTO THE AREA FROM THE LOWER MS VALLEY. WITH THIS ADVECTION...MOISTURE IS SLOWLY MAKING IT INTO THE AREA...THOUGH HAVING A TOUGH TIME SEEPING INTO THE RUGGED TERRAIN OF EASTERN KENTUCKY. AS SUCH...DEW POINTS ARE BIT OFF THIS MORNING AND HAVE UPDATED TO LOWER THEM AND BRING A MORE SLOWER INCREASE TO MOISTURE INTO THE AREA THIS AFTERNOON. AS WELL...UPDATED TEMPS FOR THEIR HOURLY TREND AND BRING TEMPERATURES UP A LITTLE QUICKER WITH THE EXCEPTION OF SOME OF THE DEEPER VALLEYS. THIS UPDATE WILL NOT REQUIRE A NEW ZFP AS THE REST OF THE FORECAST IS ON TRACK FOR NOW. WILL WAIT FOR TRENDS IN THE MODELS TO INDICATE WHEN MEASURABLE PRECIP WILL MOVE INTO THE NORTHWEST AND IF CLOUD COVER NEEDS TO BE INCREASED A LITTLE EARLIER. UPDATE ISSUED AT 656 AM EST SAT NOV 29 2014 UPDATED TO INCREASE SKY COVER A BIT MORE EARLY ON AS CLOUDS ARE QUICKLY SPREADING INTO THE AREA. TEMPERATURES CONTINUE TO SLOWLY CLIMB AND HIGHS SHOULD STILL BE IN REACH EVEN WITH THE EARLIER CLOUD COVER. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 302 AM EST SAT NOV 29 2014 THE NEXT 36 HOURS WILL FEATURE MILDER WEATHER AND SLOWLY INCREASING RAIN/DRIZZLE CHANCES ACROSS NORTHERN KENTUCKY. HIGH CLOUDS ARE STARTING TO RETREAT THIS MORNING...WITH MOSTLY CLEAR SKIES EXPECTED TO START THE DAY. MODELS ARE ADVERTISING A DECK OF 4-6KFT...CURRENTLY DEVELOPING ACROSS WESTERN TENNESSEE TO PUSH ACROSS CENTRAL/NORTHERN KENTUCKY TOWARDS MIDDAY. THIS SEEMS REASONABLE BASED ON THE CURRENT PLACEMENT OF THESE CLOUDS. NOT SURE WE WILL SUSTAIN THE CLOUD COVER TODAY...GIVEN THE ABUNDANCE OF DRY AIR AS IT WILL TAKE AWHILE TO GET HIGHER DEWPOINTS INTO THE AREA. THE RAP SEEMS TO BE ON TOP OF THE CURRENT TRENDS...SO FOLLOWED IT CLOSELY FOR TH FIRST 6 TO 12 HOURS OF THE FORECAST. BASICALLY LOOKS LIKE MORE SUNSHINE THAN CLOUDS TODAY...ESPECIALLY ACROSS SOUTHEAST KENTUCKY. THIS WILL HELP BOOST TEMPERATURES WELL UP INTO THE 50S. AREAS TO THE NORTHWEST MAY STAY AROUND 50 WITH THE CLOUDS TOWARDS MIDDAY SLOWING DOWN THE RISE. BY TONIGHT...IMPRESSIVE LOW LEVEL ISENTROPIC ASCENT RAMPS UP ACROSS CENTRAL/NORTHERN KENTUCKY WITH DRIZZLE/LIGHT RAIN DEVELOPING. OUR NORTHERN ZONES CONTINUE TO RESIDE ON THE EDGE OF THIS EXPECTED PRECIPITATION AND THUS...HAVE STAYED CLOSER TO MOS GUIDANCE WITH POPS WITH BASICALLY A SLIGHT CHANCE IN THE NORTH. ALSO WENT WITH A BUFFER ZONE OF A CHANCE OF DRIZZLE AS FAR SOUTH AS THE MOUNTAIN PARKWAY. NOT MUCH CHANGE IS EXPECTED HEADING INTO SUNDAY AS THERE ARE NO REAL SHIFTS IN THE WEATHER REGIME. IF ANYTHING...THE THREAT OF DRIZZLE/RAIN MIGHT LIFT BACK TO THE NORTH SLIGHTLY. THIS MAY KEEP MOST OF OUR WEEKEND MAINLY DRY. CLOUDS ARE STILL VERY MUCH A QUESTION MARK FOR SUNDAY...WITH A MODEL BLEND PROVIDING A NICE GRADIENT ACROSS THE AREA. HARD TO ARGUE WITH THIS AT THE MOMENT...BUT IF RAIN CHANCES RETREAT NORTHWARD...CLOUD COVER MAY ALSO RETREAT...PROVIDING MORE POTENTIAL FOR SUN ON SUNDAY. HOWEVER...TOO MUCH UNCERTAINTY TO GO ONE WAY OR THE OTHER. REGARDLESS OF CLOUD COVER...TEMPERATURES SHOULD TREND WARMER ON SUNDAY AND HAVE GONE TOWARDS THE HIGHER END OF MOS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 329 AM EST SAT NOV 29 2014 THE WEATHER PATTERN THROUGH THE LONG TERM PERIOD WILL BE RATHER ACTIVE AS A ZONAL FLOW REGIME REMAINS IN PLACE WITH SHORTWAVES TRAVERSING THE NORTHERN STATES EVERY COUPLE OF DAYS. AN ARCTIC BOUNDARY NOW SURGING SOUTH THROUGH MONTANA WILL PUSH SOUTHEASTWARD TOWARD OUR REGION EARLY NEXT WEEK BRINGING A THREAT FOR A LITTLE WINTRY PRECIPITATION. THIS FRONT WILL THEN MODIFY BUT MEANDER ABOUT THROUGH THE REST OF THE WEEK WITH PERIODIC RAIN CHANCES JUST ABOUT EACH DAY. RAIN CHANCES WILL BE ON THE INCREASE SUNDAY NIGHT INTO THE DAY ON MONDAY AS THE ARCTIC BOUNDARY SETTLES INTO AND THROUGH THE AREA. SOUTHWEST WINDS AT THE SURFACE WILL QUICKLY TURN NORTHERLY BEHIND THE FRONT AND A SHALLOW MODIFIED ARCTIC AIRMASS WILL OOZE SOUTHWARD INTO EAST KENTUCKY. TEMPERATURES WILL REACH HIGHS IN THE 50S MONDAY MORNING...AND THEN FALL DURING THE DAY. FORTUNATELY IT STILL APPEARS THAT THE BULK OF THE MOISTURE WILL HAVE SHIFTED TO OUR SOUTH BY THE TIME THE COLDER AIR MAKES IT INTO THE AREA. HOWEVER...A MIXTURE OF LIGHT SNOW AND SLEET WILL LIKELY MIX WITH ANY LINGERING RAIN OVER OUR NORTHERN COUNTIES BY LATE MONDAY AFTERNOON AND SOME FREEZING RAIN WILL BE POSSIBLE AS WELL MONDAY NIGHT AS SURFACE TEMPS EASE BELOW FREEZING OVER OUR NORTHERN COUNTIES. THIS CHANCE OF A LIGHT WINTRY MIX WILL THEN PERSIST INTO TUESDAY MORNING...BEFORE TEMPS WARM BOTH ALOFT AND AT THE SURFACE ENDING THE WINTRY PRECIP THREAT BY AFTERNOON. RIGHT NOW...THE THREAT FOR A WINTRY MIX APPEARS TO ONLY MAKE IT SOUTHWARD TO A JACKSON TO PIKEVILLE LINE AND ANY SNOW AND ICE ACCUMULATIONS SHOULD BE LIGHT AND MORE OF THE NUISANCE VARIETY. WITH THE FRONT NEAR THE AREA AND ADDITIONAL SHORTWAVE ENERGY PASSING BY TO OUR NORTH...PERIODIC BOUTS OF PRECIP APPEAR LIKELY FROM TUESDAY AFTERNOON THROUGH FRIDAY AT LEAST. FOR NOW...TEMPS SUPPORT ALL RAIN DURING THIS PERIOD...BUT THE SHALLOW NATURE OF THE PERIODIC ARCTIC INTRUSIONS TO OUR NORTH MAY NOT BE HANDLED WELL BY THE MODELS SO CONFIDENCE IN THE FORECAST DETAILS IS NOT GREAT BEYOND MIDWEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 111 PM EST SAT NOV 29 2014 VFR WILL PERSIST THROUGH MUCH OF THE PERIOD BUT MAINLY OVER EXTREME EAST AND SOUTHEAST KENTUCKY. WINDS WILL GUST OUT OF THE SOUTH AND SOUTHWEST THROUGH MUCH OF THE PERIOD. WILL HAVE TO KEEP CLOUD COVER A CONSTANT THROUGH THE TAF PERIOD NOW AS IT APPEARS THE LOW LEVEL MOISTURE MOVING IN IS A BIT FASTER THAN ANTICIPATED. AN MVFR CEILING DECK IS MAKING IT INTO THE WEST TAF SITES...MAINLY SME...LOZ...AND SYM. WILL KEEP THIS CEILING WITH THESE LOCATIONS FOR MUCH OF THE PERIOD. ANY RAINFALL DURING THIS PERIOD WILL ONLY EFFECT SYM AND THIS WILL BE AT THE END OF THE TAF PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SHALLENBERGER SHORT TERM...KAS LONG TERM...ABE AVIATION...SHALLENBERGER
AREA FORECAST DISCUSSION
NWS JACKSON KY
1007 AM EST SAT NOV 29 2014 .UPDATE... ISSUED AT 1001 AM EST SAT NOV 29 2014 CURRENT CONDITIONS ACROSS THE AREA TODAY FEATURE SOME MID AND UPPER LEVEL CLOUD COVER MOVING IN FROM THE WEST WHILE SOME LOWER LEVEL CLOUD COVER IN SOUTHERLY FLOW MOVES NORTH INTO THE AREA FROM THE LOWER MS VALLEY. WITH THIS ADVECTION...MOISTURE IS SLOWLY MAKING IT INTO THE AREA...THOUGH HAVING A TOUGH TIME SEEPING INTO THE RUGGED TERRAIN OF EASTERN KENTUCKY. AS SUCH...DEW POINTS ARE BIT OFF THIS MORNING AND HAVE UPDATED TO LOWER THEM AND BRING A MORE SLOWER INCREASE TO MOISTURE INTO THE AREA THIS AFTERNOON. AS WELL...UPDATED TEMPS FOR THEIR HOURLY TREND AND BRING TEMPERATURES UP A LITTLE QUICKER WITH THE EXCEPTION OF SOME OF THE DEEPER VALLEYS. THIS UPDATE WILL NOT REQUIRE A NEW ZFP AS THE REST OF THE FORECAST IS ON TRACK FOR NOW. WILL WAIT FOR TRENDS IN THE MODELS TO INDICATE WHEN MEASURABLE PRECIP WILL MOVE INTO THE NORTHWEST AND IF CLOUD COVER NEEDS TO BE INCREASED A LITTLE EARLIER. UPDATE ISSUED AT 656 AM EST SAT NOV 29 2014 UPDATED TO INCREASE SKY COVER A BIT MORE EARLY ON AS CLOUDS ARE QUICKLY SPREADING INTO THE AREA. TEMPERATURES CONTINUE TO SLOWLY CLIMB AND HIGHS SHOULD STILL BE IN REACH EVEN WITH THE EARLIER CLOUD COVER. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 302 AM EST SAT NOV 29 2014 THE NEXT 36 HOURS WILL FEATURE MILDER WEATHER AND SLOWLY INCREASING RAIN/DRIZZLE CHANCES ACROSS NORTHERN KENTUCKY. HIGH CLOUDS ARE STARTING TO RETREAT THIS MORNING...WITH MOSTLY CLEAR SKIES EXPECTED TO START THE DAY. MODELS ARE ADVERTISING A DECK OF 4-6KFT...CURRENTLY DEVELOPING ACROSS WESTERN TENNESSEE TO PUSH ACROSS CENTRAL/NORTHERN KENTUCKY TOWARDS MIDDAY. THIS SEEMS REASONABLE BASED ON THE CURRENT PLACEMENT OF THESE CLOUDS. NOT SURE WE WILL SUSTAIN THE CLOUD COVER TODAY...GIVEN THE ABUNDANCE OF DRY AIR AS IT WILL TAKE AWHILE TO GET HIGHER DEWPOINTS INTO THE AREA. THE RAP SEEMS TO BE ON TOP OF THE CURRENT TRENDS...SO FOLLOWED IT CLOSELY FOR TH FIRST 6 TO 12 HOURS OF THE FORECAST. BASICALLY LOOKS LIKE MORE SUNSHINE THAN CLOUDS TODAY...ESPECIALLY ACROSS SOUTHEAST KENTUCKY. THIS WILL HELP BOOST TEMPERATURES WELL UP INTO THE 50S. AREAS TO THE NORTHWEST MAY STAY AROUND 50 WITH THE CLOUDS TOWARDS MIDDAY SLOWING DOWN THE RISE. BY TONIGHT...IMPRESSIVE LOW LEVEL ISENTROPIC ASCENT RAMPS UP ACROSS CENTRAL/NORTHERN KENTUCKY WITH DRIZZLE/LIGHT RAIN DEVELOPING. OUR NORTHERN ZONES CONTINUE TO RESIDE ON THE EDGE OF THIS EXPECTED PRECIPITATION AND THUS...HAVE STAYED CLOSER TO MOS GUIDANCE WITH POPS WITH BASICALLY A SLIGHT CHANCE IN THE NORTH. ALSO WENT WITH A BUFFER ZONE OF A CHANCE OF DRIZZLE AS FAR SOUTH AS THE MOUNTAIN PARKWAY. NOT MUCH CHANGE IS EXPECTED HEADING INTO SUNDAY AS THERE ARE NO REAL SHIFTS IN THE WEATHER REGIME. IF ANYTHING...THE THREAT OF DRIZZLE/RAIN MIGHT LIFT BACK TO THE NORTH SLIGHTLY. THIS MAY KEEP MOST OF OUR WEEKEND MAINLY DRY. CLOUDS ARE STILL VERY MUCH A QUESTION MARK FOR SUNDAY...WITH A MODEL BLEND PROVIDING A NICE GRADIENT ACROSS THE AREA. HARD TO ARGUE WITH THIS AT THE MOMENT...BUT IF RAIN CHANCES RETREAT NORTHWARD...CLOUD COVER MAY ALSO RETREAT...PROVIDING MORE POTENTIAL FOR SUN ON SUNDAY. HOWEVER...TOO MUCH UNCERTAINTY TO GO ONE WAY OR THE OTHER. REGARDLESS OF CLOUD COVER...TEMPERATURES SHOULD TREND WARMER ON SUNDAY AND HAVE GONE TOWARDS THE HIGHER END OF MOS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 329 AM EST SAT NOV 29 2014 THE WEATHER PATTERN THROUGH THE LONG TERM PERIOD WILL BE RATHER ACTIVE AS A ZONAL FLOW REGIME REMAINS IN PLACE WITH SHORTWAVES TRAVERSING THE NORTHERN STATES EVERY COUPLE OF DAYS. AN ARCTIC BOUNDARY NOW SURGING SOUTH THROUGH MONTANA WILL PUSH SOUTHEASTWARD TOWARD OUR REGION EARLY NEXT WEEK BRINGING A THREAT FOR A LITTLE WINTRY PRECIPITATION. THIS FRONT WILL THEN MODIFY BUT MEANDER ABOUT THROUGH THE REST OF THE WEEK WITH PERIODIC RAIN CHANCES JUST ABOUT EACH DAY. RAIN CHANCES WILL BE ON THE INCREASE SUNDAY NIGHT INTO THE DAY ON MONDAY AS THE ARCTIC BOUNDARY SETTLES INTO AND THROUGH THE AREA. SOUTHWEST WINDS AT THE SURFACE WILL QUICKLY TURN NORTHERLY BEHIND THE FRONT AND A SHALLOW MODIFIED ARCTIC AIRMASS WILL OOZE SOUTHWARD INTO EAST KENTUCKY. TEMPERATURES WILL REACH HIGHS IN THE 50S MONDAY MORNING...AND THEN FALL DURING THE DAY. FORTUNATELY IT STILL APPEARS THAT THE BULK OF THE MOISTURE WILL HAVE SHIFTED TO OUR SOUTH BY THE TIME THE COLDER AIR MAKES IT INTO THE AREA. HOWEVER...A MIXTURE OF LIGHT SNOW AND SLEET WILL LIKELY MIX WITH ANY LINGERING RAIN OVER OUR NORTHERN COUNTIES BY LATE MONDAY AFTERNOON AND SOME FREEZING RAIN WILL BE POSSIBLE AS WELL MONDAY NIGHT AS SURFACE TEMPS EASE BELOW FREEZING OVER OUR NORTHERN COUNTIES. THIS CHANCE OF A LIGHT WINTRY MIX WILL THEN PERSIST INTO TUESDAY MORNING...BEFORE TEMPS WARM BOTH ALOFT AND AT THE SURFACE ENDING THE WINTRY PRECIP THREAT BY AFTERNOON. RIGHT NOW...THE THREAT FOR A WINTRY MIX APPEARS TO ONLY MAKE IT SOUTHWARD TO A JACKSON TO PIKEVILLE LINE AND ANY SNOW AND ICE ACCUMULATIONS SHOULD BE LIGHT AND MORE OF THE NUISANCE VARIETY. WITH THE FRONT NEAR THE AREA AND ADDITIONAL SHORTWAVE ENERGY PASSING BY TO OUR NORTH...PERIODIC BOUTS OF PRECIP APPEAR LIKELY FROM TUESDAY AFTERNOON THROUGH FRIDAY AT LEAST. FOR NOW...TEMPS SUPPORT ALL RAIN DURING THIS PERIOD...BUT THE SHALLOW NATURE OF THE PERIODIC ARCTIC INTRUSIONS TO OUR NORTH MAY NOT BE HANDLED WELL BY THE MODELS SO CONFIDENCE IN THE FORECAST DETAILS IS NOT GREAT BEYOND MIDWEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 656 AM EST SAT NOV 29 2014 VFR CONDITIONS WILL LIKELY PERSIST THROUGH THE FORECAST PERIOD. THE BEST THREAT OF SOME MVFR CIGS CREEPING INTO THE AREA WILL BE LATE TONIGHT AS STRONG MOISTURE TRANSPORT BRINGS IN SOME SHALLOW MOISTURE. HOWEVER...AT THIS TIME...PLAN TO KEEP EVERYTHING VFR THROUGH TONIGHT. WILL HAVE SOME LOW LEVEL WIND SHEAR THIS MORNING BEFORE WE BEGIN TO MIX DOWN SOME BETTE WINDS AND AGAIN TONIGHT. WINDS JUST OFF THE SURFACE ARE 40 TO 45 KNOTS. WHILE THERE IS SOME UNCERTAINTY WITH THE MIXING HEIGHTS TODAY...A COMPROMISED SOLUTION WOULD STILL YIELD SOUTH/SOUTHWEST WINDS GUSTING TO 2O TO 30 MPH. WINDS SHOULD PICK UP BY MID TO LATE MORNING AND PERSIST THROUGH MID AFTERNOON...BEFORE SUBSIDING AGAIN THIS EVENING. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SHALLENBERGER SHORT TERM...KAS LONG TERM...ABE AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
656 AM EST SAT NOV 29 2014 .UPDATE... ISSUED AT 656 AM EST SAT NOV 29 2014 UPDATED TO INCREASE SKY COVER A BIT MORE EARLY ON AS CLOUDS ARE QUICKLY SPREADING INTO THE AREA. TEMPERATURES CONTINUE TO SLOWLY CLIMB AND HIGHS SHOULD STILL BE IN REACH EVEN WITH THE EARLIER CLOUD COVER. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 302 AM EST SAT NOV 29 2014 THE NEXT 36 HOURS WILL FEATURE MILDER WEATHER AND SLOWLY INCREASING RAIN/DRIZZLE CHANCES ACROSS NORTHERN KENTUCKY. HIGH CLOUDS ARE STARTING TO RETREAT THIS MORNING...WITH MOSTLY CLEAR SKIES EXPECTED TO START THE DAY. MODELS ARE ADVERTISING A DECK OF 4-6KFT...CURRENTLY DEVELOPING ACROSS WESTERN TENNESSEE TO PUSH ACROSS CENTRAL/NORTHERN KENTUCKY TOWARDS MIDDAY. THIS SEEMS REASONABLE BASED ON THE CURRENT PLACEMENT OF THESE CLOUDS. NOT SURE WE WILL SUSTAIN THE CLOUD COVER TODAY...GIVEN THE ABUNDANCE OF DRY AIR AS IT WILL TAKE AWHILE TO GET HIGHER DEWPOINTS INTO THE AREA. THE RAP SEEMS TO BE ON TOP OF THE CURRENT TRENDS...SO FOLLOWED IT CLOSELY FOR TH FIRST 6 TO 12 HOURS OF THE FORECAST. BASICALLY LOOKS LIKE MORE SUNSHINE THAN CLOUDS TODAY...ESPECIALLY ACROSS SOUTHEAST KENTUCKY. THIS WILL HELP BOOST TEMPERATURES WELL UP INTO THE 50S. AREAS TO THE NORTHWEST MAY STAY AROUND 50 WITH THE CLOUDS TOWARDS MIDDAY SLOWING DOWN THE RISE. BY TONIGHT...IMPRESSIVE LOW LEVEL ISENTROPIC ASCENT RAMPS UP ACROSS CENTRAL/NORTHERN KENTUCKY WITH DRIZZLE/LIGHT RAIN DEVELOPING. OUR NORTHERN ZONES CONTINUE TO RESIDE ON THE EDGE OF THIS EXPECTED PRECIPITATION AND THUS...HAVE STAYED CLOSER TO MOS GUIDANCE WITH POPS WITH BASICALLY A SLIGHT CHANCE IN THE NORTH. ALSO WENT WITH A BUFFER ZONE OF A CHANCE OF DRIZZLE AS FAR SOUTH AS THE MOUNTAIN PARKWAY. NOT MUCH CHANGE IS EXPECTED HEADING INTO SUNDAY AS THERE ARE NO REAL SHIFTS IN THE WEATHER REGIME. IF ANYTHING...THE THREAT OF DRIZZLE/RAIN MIGHT LIFT BACK TO THE NORTH SLIGHTLY. THIS MAY KEEP MOST OF OUR WEEKEND MAINLY DRY. CLOUDS ARE STILL VERY MUCH A QUESTION MARK FOR SUNDAY...WITH A MODEL BLEND PROVIDING A NICE GRADIENT ACROSS THE AREA. HARD TO ARGUE WITH THIS AT THE MOMENT...BUT IF RAIN CHANCES RETREAT NORTHWARD...CLOUD COVER MAY ALSO RETREAT...PROVIDING MORE POTENTIAL FOR SUN ON SUNDAY. HOWEVER...TOO MUCH UNCERTAINTY TO GO ONE WAY OR THE OTHER. REGARDLESS OF CLOUD COVER...TEMPERATURES SHOULD TREND WARMER ON SUNDAY AND HAVE GONE TOWARDS THE HIGHER END OF MOS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 329 AM EST SAT NOV 29 2014 THE WEATHER PATTERN THROUGH THE LONG TERM PERIOD WILL BE RATHER ACTIVE AS A ZONAL FLOW REGIME REMAINS IN PLACE WITH SHORTWAVES TRAVERSING THE NORTHERN STATES EVERY COUPLE OF DAYS. AN ARCTIC BOUNDARY NOW SURGING SOUTH THROUGH MONTANA WILL PUSH SOUTHEASTWARD TOWARD OUR REGION EARLY NEXT WEEK BRINGING A THREAT FOR A LITTLE WINTRY PRECIPITATION. THIS FRONT WILL THEN MODIFY BUT MEANDER ABOUT THROUGH THE REST OF THE WEEK WITH PERIODIC RAIN CHANCES JUST ABOUT EACH DAY. RAIN CHANCES WILL BE ON THE INCREASE SUNDAY NIGHT INTO THE DAY ON MONDAY AS THE ARCTIC BOUNDARY SETTLES INTO AND THROUGH THE AREA. SOUTHWEST WINDS AT THE SURFACE WILL QUICKLY TURN NORTHERLY BEHIND THE FRONT AND A SHALLOW MODIFIED ARCTIC AIRMASS WILL OOZE SOUTHWARD INTO EAST KENTUCKY. TEMPERATURES WILL REACH HIGHS IN THE 50S MONDAY MORNING...AND THEN FALL DURING THE DAY. FORTUNATELY IT STILL APPEARS THAT THE BULK OF THE MOISTURE WILL HAVE SHIFTED TO OUR SOUTH BY THE TIME THE COLDER AIR MAKES IT INTO THE AREA. HOWEVER...A MIXTURE OF LIGHT SNOW AND SLEET WILL LIKELY MIX WITH ANY LINGERING RAIN OVER OUR NORTHERN COUNTIES BY LATE MONDAY AFTERNOON AND SOME FREEZING RAIN WILL BE POSSIBLE AS WELL MONDAY NIGHT AS SURFACE TEMPS EASE BELOW FREEZING OVER OUR NORTHERN COUNTIES. THIS CHANCE OF A LIGHT WINTRY MIX WILL THEN PERSIST INTO TUESDAY MORNING...BEFORE TEMPS WARM BOTH ALOFT AND AT THE SURFACE ENDING THE WINTRY PRECIP THREAT BY AFTERNOON. RIGHT NOW...THE THREAT FOR A WINTRY MIX APPEARS TO ONLY MAKE IT SOUTHWARD TO A JACKSON TO PIKEVILLE LINE AND ANY SNOW AND ICE ACCUMULATIONS SHOULD BE LIGHT AND MORE OF THE NUISANCE VARIETY. WITH THE FRONT NEAR THE AREA AND ADDITIONAL SHORTWAVE ENERGY PASSING BY TO OUR NORTH...PERIODIC BOUTS OF PRECIP APPEAR LIKELY FROM TUESDAY AFTERNOON THROUGH FRIDAY AT LEAST. FOR NOW...TEMPS SUPPORT ALL RAIN DURING THIS PERIOD...BUT THE SHALLOW NATURE OF THE PERIODIC ARCTIC INTRUSIONS TO OUR NORTH MAY NOT BE HANDLED WELL BY THE MODELS SO CONFIDENCE IN THE FORECAST DETAILS IS NOT GREAT BEYOND MIDWEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 656 AM EST SAT NOV 29 2014 VFR CONDITIONS WILL LIKELY PERSIST THROUGH THE FORECAST PERIOD. THE BEST THREAT OF SOME MVFR CIGS CREEPING INTO THE AREA WILL BE LATE TONIGHT AS STRONG MOISTURE TRANSPORT BRINGS IN SOME SHALLOW MOISTURE. HOWEVER...AT THIS TIME...PLAN TO KEEP EVERYTHING VFR THROUGH TONIGHT. WILL HAVE SOME LOW LEVEL WIND SHEAR THIS MORNING BEFORE WE BEGIN TO MIX DOWN SOME BETTE WINDS AND AGAIN TONIGHT. WINDS JUST OFF THE SURFACE ARE 40 TO 45 KNOTS. WHILE THERE IS SOME UNCERTAINTY WITH THE MIXING HEIGHTS TODAY...A COMPROMISED SOLUTION WOULD STILL YIELD SOUTH/SOUTHWEST WINDS GUSTING TO 2O TO 30 MPH. WINDS SHOULD PICK UP BY MID TO LATE MORNING AND PERSIST THROUGH MID AFTERNOON...BEFORE SUBSIDING AGAIN THIS EVENING. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KAS SHORT TERM...KAS LONG TERM...ABE AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
329 AM EST SAT NOV 29 2014 .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 302 AM EST SAT NOV 29 2014 THE NEXT 36 HOURS WILL FEATURE MILDER WEATHER AND SLOWLY INCREASING RAIN/DRIZZLE CHANCES ACROSS NORTHERN KENTUCKY. HIGH CLOUDS ARE STARTING TO RETREAT THIS MORNING...WITH MOSTLY CLEAR SKIES EXPECTED TO START THE DAY. MODELS ARE ADVERTISING A DECK OF 4-6KFT...CURRENTLY DEVELOPING ACROSS WESTERN TENNESSEE TO PUSH ACROSS CENTRAL/NORTHERN KENTUCKY TOWARDS MIDDAY. THIS SEEMS REASONABLE BASED ON THE CURRENT PLACEMENT OF THESE CLOUDS. NOT SURE WE WILL SUSTAIN THE CLOUD COVER TODAY...GIVEN THE ABUNDANCE OF DRY AIR AS IT WILL TAKE AWHILE TO GET HIGHER DEWPOINTS INTO THE AREA. THE RAP SEEMS TO BE ON TOP OF THE CURRENT TRENDS...SO FOLLOWED IT CLOSELY FOR TH FIRST 6 TO 12 HOURS OF THE FORECAST. BASICALLY LOOKS LIKE MORE SUNSHINE THAN CLOUDS TODAY...ESPECIALLY ACROSS SOUTHEAST KENTUCKY. THIS WILL HELP BOOST TEMPERATURES WELL UP INTO THE 50S. AREAS TO THE NORTHWEST MAY STAY AROUND 50 WITH THE CLOUDS TOWARDS MIDDAY SLOWING DOWN THE RISE. BY TONIGHT...IMPRESSIVE LOW LEVEL ISENTROPIC ASCENT RAMPS UP ACROSS CENTRAL/NORTHERN KENTUCKY WITH DRIZZLE/LIGHT RAIN DEVELOPING. OUR NORTHERN ZONES CONTINUE TO RESIDE ON THE EDGE OF THIS EXPECTED PRECIPITATION AND THUS...HAVE STAYED CLOSER TO MOS GUIDANCE WITH POPS WITH BASICALLY A SLIGHT CHANCE IN THE NORTH. ALSO WENT WITH A BUFFER ZONE OF A CHANCE OF DRIZZLE AS FAR SOUTH AS THE MOUNTAIN PARKWAY. NOT MUCH CHANGE IS EXPECTED HEADING INTO SUNDAY AS THERE ARE NO REAL SHIFTS IN THE WEATHER REGIME. IF ANYTHING...THE THREAT OF DRIZZLE/RAIN MIGHT LIFT BACK TO THE NORTH SLIGHTLY. THIS MAY KEEP MOST OF OUR WEEKEND MAINLY DRY. CLOUDS ARE STILL VERY MUCH A QUESTION MARK FOR SUNDAY...WITH A MODEL BLEND PROVIDING A NICE GRADIENT ACROSS THE AREA. HARD TO ARGUE WITH THIS AT THE MOMENT...BUT IF RAIN CHANCES RETREAT NORTHWARD...CLOUD COVER MAY ALSO RETREAT...PROVIDING MORE POTENTIAL FOR SUN ON SUNDAY. HOWEVER...TOO MUCH UNCERTAINTY TO GO ONE WAY OR THE OTHER. REGARDLESS OF CLOUD COVER...TEMPERATURES SHOULD TREND WARMER ON SUNDAY AND HAVE GONE TOWARDS THE HIGHER END OF MOS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 329 AM EST SAT NOV 29 2014 THE WEATHER PATTERN THROUGH THE LONG TERM PERIOD WILL BE RATHER ACTIVE AS A ZONAL FLOW REGIME REMAINS IN PLACE WITH SHORTWAVES TRAVERSING THE NORTHERN STATES EVERY COUPLE OF DAYS. AN ARCTIC BOUNDARY NOW SURGING SOUTH THROUGH MONTANA WILL PUSH SOUTHEASTWARD TOWARD OUR REGION EARLY NEXT WEEK BRINGING A THREAT FOR A LITTLE WINTRY PRECIPITATION. THIS FRONT WILL THEN MODIFY BUT MEANDER ABOUT THROUGH THE REST OF THE WEEK WITH PERIODIC RAIN CHANCES JUST ABOUT EACH DAY. RAIN CHANCES WILL BE ON THE INCREASE SUNDAY NIGHT INTO THE DAY ON MONDAY AS THE ARCTIC BOUNDARY SETTLES INTO AND THROUGH THE AREA. SOUTHWEST WINDS AT THE SURFACE WILL QUICKLY TURN NORTHERLY BEHIND THE FRONT AND A SHALLOW MODIFIED ARCTIC AIRMASS WILL OOZE SOUTHWARD INTO EAST KENTUCKY. TEMPERATURES WILL REACH HIGHS IN THE 50S MONDAY MORNING...AND THEN FALL DURING THE DAY. FORTUNATELY IT STILL APPEARS THAT THE BULK OF THE MOISTURE WILL HAVE SHIFTED TO OUR SOUTH BY THE TIME THE COLDER AIR MAKES IT INTO THE AREA. HOWEVER...A MIXTURE OF LIGHT SNOW AND SLEET WILL LIKELY MIX WITH ANY LINGERING RAIN OVER OUR NORTHERN COUNTIES BY LATE MONDAY AFTERNOON AND SOME FREEZING RAIN WILL BE POSSIBLE AS WELL MONDAY NIGHT AS SURFACE TEMPS EASE BELOW FREEZING OVER OUR NORTHERN COUNTIES. THIS CHANCE OF A LIGHT WINTRY MIX WILL THEN PERSIST INTO TUESDAY MORNING...BEFORE TEMPS WARM BOTH ALOFT AND AT THE SURFACE ENDING THE WINTRY PRECIP THREAT BY AFTERNOON. RIGHT NOW...THE THREAT FOR A WINTRY MIX APPEARS TO ONLY MAKE IT SOUTHWARD TO A JACKSON TO PIKEVILLE LINE AND ANY SNOW AND ICE ACCUMULATIONS SHOULD BE LIGHT AND MORE OF THE NUISANCE VARIETY. WITH THE FRONT NEAR THE AREA AND ADDITIONAL SHORTWAVE ENERGY PASSING BY TO OUR NORTH...PERIODIC BOUTS OF PRECIP APPEAR LIKELY FROM TUESDAY AFTERNOON THROUGH FRIDAY AT LEAST. FOR NOW...TEMPS SUPPORT ALL RAIN DURING THIS PERIOD...BUT THE SHALLOW NATURE OF THE PERIODIC ARCTIC INTRUSIONS TO OUR NORTH MAY NOT BE HANDLED WELL BY THE MODELS SO CONFIDENCE IN THE FORECAST DETAILS IS NOT GREAT BEYOND MIDWEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1256 AM EST SAT NOV 29 2014 VFR CONDITIONS WILL LIKELY PERSIST THROUGH THE FORECAST PERIOD. THE BEST THREAT OF SOME MVFR CIGS CREEPING INTO THE AREA WILL BE LATE TONIGHT AS STRONG MOISTURE TRANSPORT BRINGS IN SOME SHALLOW MOISTURE. HOWEVER...AT THIS TIME...PLAN TO KEEP EVERYTHING VFR THROUGH TONIGHT. WILL BRING BACK SOME LOW LEVEL WIND SHEAR FOR THE REST OF THE NIGHT AND AGAIN TONIGHT AS STRONG INVERSIONS SET UP BOTH NIGHTS...WITH WINDS JUST OFF THE SURFACE OF 40 TO 45 KNOTS. WHILE THERE IS SOME UNCERTAINTY WITH THE MIXING HEIGHTS TODAY...A COMPROMISED SOLUTION WOULD STILL YIELD SOUTH/SOUTHWEST WINDS GUSTING TO 2O TO 30 MPH. I WOULDN`T BE SURPRISED TO SEE A FEW WIND GUSTS EVEN A BIT HIGHER THAN THIS. THIS WINDS SHOULD PICK UP BY MID TO LATE MORNING AND PERSIST THROUGH MID AFTERNOON...BEFORE SUBSIDING AGAIN THIS EVENING. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...KAS LONG TERM...ABE AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
302 AM EST SAT NOV 29 2014 .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 302 AM EST SAT NOV 29 2014 THE NEXT 36 HOURS WILL FEATURE MILDER WEATHER AND SLOWLY INCREASING RAIN/DRIZZLE CHANCES ACROSS NORTHERN KENTUCKY. HIGH CLOUDS ARE STARTING TO RETREAT THIS MORNING...WITH MOSTLY CLEAR SKIES EXPECTED TO START THE DAY. MODELS ARE ADVERTISING A DECK OF 4-6KFT...CURRENTLY DEVELOPING ACROSS WESTERN TENNESSEE TO PUSH ACROSS CENTRAL/NORTHERN KENTUCKY TOWARDS MIDDAY. THIS SEEMS REASONABLE BASED ON THE CURRENT PLACEMENT OF THESE CLOUDS. NOT SURE WE WILL SUSTAIN THE CLOUD COVER TODAY...GIVEN THE ABUNDANCE OF DRY AIR AS IT WILL TAKE AWHILE TO GET HIGHER DEWPOINTS INTO THE AREA. THE RAP SEEMS TO BE ON TOP OF THE CURRENT TRENDS...SO FOLLOWED IT CLOSELY FOR TH FIRST 6 TO 12 HOURS OF THE FORECAST. BASICALLY LOOKS LIKE MORE SUNSHINE THAN CLOUDS TODAY...ESPECIALLY ACROSS SOUTHEAST KENTUCKY. THIS WILL HELP BOOST TEMPERATURES WELL UP INTO THE 50S. AREAS TO THE NORTHWEST MAY STAY AROUND 50 WITH THE CLOUDS TOWARDS MIDDAY SLOWING DOWN THE RISE. BY TONIGHT...IMPRESSIVE LOW LEVEL ISENTROPIC ASCENT RAMPS UP ACROSS CENTRAL/NORTHERN KENTUCKY WITH DRIZZLE/LIGHT RAIN DEVELOPING. OUR NORTHERN ZONES CONTINUE TO RESIDE ON THE EDGE OF THIS EXPECTED PRECIPITATION AND THUS...HAVE STAYED CLOSER TO MOS GUIDANCE WITH POPS WITH BASICALLY A SLIGHT CHANCE IN THE NORTH. ALSO WENT WITH A BUFFER ZONE OF A CHANCE OF DRIZZLE AS FAR SOUTH AS THE MOUNTAIN PARKWAY. NOT MUCH CHANGE IS EXPECTED HEADING INTO SUNDAY AS THERE ARE NO REAL SHIFTS IN THE WEATHER REGIME. IF ANYTHING...THE THREAT OF DRIZZLE/RAIN MIGHT LIFT BACK TO THE NORTH SLIGHTLY. THIS MAY KEEP MOST OF OUR WEEKEND MAINLY DRY. CLOUDS ARE STILL VERY MUCH A QUESTION MARK FOR SUNDAY...WITH A MODEL BLEND PROVIDING A NICE GRADIENT ACROSS THE AREA. HARD TO ARGUE WITH THIS AT THE MOMENT...BUT IF RAIN CHANCES RETREAT NORTHWARD...IT MAY BE CLOUD COVER MAY ALSO RETREAT...PROVIDING MORE POTENTIAL FOR SUN ON SUNDAY. HOWEVER...TOO MUCH UNCERTAINTY TO GO ONE WAY OR THE OTHER. REGARDLESS OF CLOUD COVER...TEMPERATURES SHOULD TREND WARMER ON SUNDAY AND HAVE GONE TOWARDS THE HIGHER END OF MOS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 302 AM EST SAT NOV 29 2014 LONG TERM DISCUSSION TO FOLLOW SHORTLY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1256 AM EST SAT NOV 29 2014 VFR CONDITIONS WILL LIKELY PERSIST THROUGH THE FORECAST PERIOD. THE BEST THREAT OF SOME MVFR CIGS CREEPING INTO THE AREA WILL BE LATE TONIGHT AS STRONG MOISTURE TRANSPORT BRINGS IN SOME SHALLOW MOISTURE. HOWEVER...AT THIS TIME...PLAN TO KEEP EVERYTHING VFR THROUGH TONIGHT. WILL BRING BACK SOME LOW LEVEL WIND SHEAR FOR THE REST OF THE NIGHT AND AGAIN TONIGHT AS STRONG INVERSIONS SET UP BOTH NIGHTS...WITH WINDS JUST OFF THE SURFACE OF 40 TO 45 KNOTS. WHILE THERE IS SOME UNCERTAINTY WITH THE MIXING HEIGHTS TODAY...A COMPROMISED SOLUTION WOULD STILL YIELD SOUTH/SOUTHWEST WINDS GUSTING TO 2O TO 30 MPH. I WOULDN`T BE SURPRISED TO SEE A FEW WIND GUSTS EVEN A BIT HIGHER THAN THIS. THIS WINDS SHOULD PICK UP BY MID TO LATE MORNING AND PERSIST THROUGH MID AFTERNOON...BEFORE SUBSIDING AGAIN THIS EVENING. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...KAS LONG TERM...ABE AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1256 AM EST SAT NOV 29 2014 .UPDATE... ISSUED AT 1256 AM EST SAT NOV 29 2014 UPDATED TO FRESHEN UP THE HOURLY GRIDS. WE SHOULD SEE RIDGE VALLEY SPLITS GETTING STEEPER AS THE NIGHT GOES ON AS A STRONG INVERSION SETS UP WITH WINDS UP TO 40 KNOTS JUST OFF THE SURFACE. LATEST RAP DOESN`T REALLY JIVE WITH THE NAM WHEN IT COMES TO MIXING HEIGHTS THIS AFTERNOON. THE RAP SUGGEST MODEST MIXING HEIGHTS WITH GOOD WIND GUST POTENTIAL WHILE THE NAM HAS VERY LITTLE IF ANY MIXING HEIGHTS. THIS WILL MAKE FOR A TRICKY DAYTIME FORECAST TODAY. UPDATE ISSUED AT 1052 PM EST FRI NOV 28 2014 MADE FURTHER ADJUSTMENTS TO 1ST PERIOD TEMPS LATE THIS EVENING... EXPANDING THE AREA OF COLDER VALLEYS. UPDATE ISSUED AT 746 PM EST FRI NOV 28 2014 TEMPS HAVE FALLEN OFF A BIT FASTER THAN WAS FORECAST...ESPECIALLY IN DEEP VALLEYS. HAVE LOWERED VALLEY MINS A LITTLE BIT FOR TONIGHT. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 335 PM EST FRI NOV 28 2014 CURRENT SURFACE ANALYSIS AS OF 20Z SHOWS SURFACE HIGH PRESSURE DRAPED ALONG THE APPALACHIAN CHAIN. THIS HAS ALLOWED FOR DRY CONDITIONS ACROSS EASTERN KENTUCKY WITH SURFACE SOUTHERLY WINDS BEGINNING TO SET UP INTO THE AREA THIS AFTERNOON. NORTHWEST FLOW STILL CONTINUES IN THE UPPER LEVELS AS CLOUD COVER AHEAD OF A DEVELOPING WARM FRONT OVER THE MID MS RIVER VALLEY CONTINUES TO MOVE INTO EASTERN KENTUCKY. THIS CONTINUED MID AND UPPER LEVEL CLOUD COVER MOVING INTO MAINLY THE NORTHERN PART OF THE FORECAST AREA WILL POSE A DIFFICULT TEMPERATURE FORECAST FOR TONIGHT AS SOME OF THE DEEPER EASTERN VALLEYS WILL DROP OFF QUICK EARLY INTO THE NIGHT BUT MAY BECOME STEADY LATE. WITH THE COUPLED INSULATION FROM CLOUD COVER AND INCREASED SOUTHWEST FLOW BRINGING WARMER AIR INTO THE AREA...THINKING THESE DEEP VALLEY LOWS WILL NOT REALIZE THEIR FULL POTENTIAL WITH MIN TEMPS DESPITE DEW POINTS IN IN THE LOWER 20S. THIS IS ALSO COMPLICATED BY THE DEVELOPING LOW LEVEL JET AHEAD OF THE NEXT SYSTEM AND WHETHER IT WILL MIX TO THE SURFACE AT TIMES OVERNIGHT. THIS LIKELY WON/T HAPPEN IN THE DEEPER VALLEYS TO THE EAST BUT THE SHALLOWER VALLEYS IN THE WEST WILL BE PROBLEMATIC AT BEST. AT THIS POINT WILL EXPECT MOST LOCATIONS IN WESTERN PORTIONS OF THE FORECAST AREA TO REACH THEIR LOW BEFORE 06Z AND STAY MIXED NEARLY ALL NIGHT. LOCATIONS IN THE EAST WILL REACH THEIR LOWS LATER IN THE NIGHT WITH MID 20S FOR LOWS IN THE DEEPER VALLEYS. HEADED INTO THE DAY ON SATURDAY WITH GRADIENT ON THE INCREASE...MODEL SOUNDINGS SHOW A 50 TO 60 KNOT LOW LEVEL JET DEVELOPING...SOME LOCATIONS COULD SEE SOME 30 KNOT GUSTS INTO SATURDAY AFTERNOON...BUT MAINLY THOSE HIGHER ELEVATIONS AS THE INVERSION LOOKS TO HANG AROUND A BIT LONGER THROUGH THE DAY KEEPING THE STRONGER WINDS OUT OF THE VALLEY AREAS. HAVE PUT THESE VALUES INTO THE FORECAST AS WELL. TEMPERATURES FOR SATURDAY AFTERNOON WILL BE A BIT TRICKY WITH CLOUD COVER HANGING AROUND AND WARMER AIR BEING ADVECTED INTO THE AREA. THE BOUNDARY LAYER WILL STILL BE QUITE DRY STILL HEADING INTO THIS EVENT AS WELL WITH DEW POINTS STILL IN THE LOW 30S BY SATURDAY AFTERNOON. MENTIONING THE DRY AIR IN PLACE FOR SATURDAY NIGHT...THIS WILL BE PRESENT AT THE SURFACE WITH QUITE A DRY MID LEVEL IN PLACE TO START THIS EVENT. WITH A SHALLOW MOIST LAYER ONLY UP TO 800MB AND LITTLE LIFT MAKING IT INTO EASTERN KENTUCKY...EXPECTING ONLY A SLIGHT TO LOW CHANCE OF MEASURABLE PRECIP TO MAKE IT INTO THE BLUEGRASS COUNTIES. IN FACT...EVEN THE NAM WHICH IS USUALLY BIASED TOWARD BEING WETTER SHOWS THE LOW LEVELS STRUGGLING TO MOISTEN UP. WENT WITH LOW CHANCE POPS INTO SUNDAY MORNING AND NO QPF FORECAST. LOW TEMPS FOR SATURDAY NIGHT WILL BE LATER IN THE NIGHT AND THOSE MAINLY IN THE VALLEYS AS RIDGE TEMPS WILL BE NEAR STEADY DUE TO INCREASED WARM AIR ADVECTION. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 335 PM EST FRI NOV 28 2014 MODELS HAVE COME INTO MUCH BETTER AGREEMENT THROUGH THE MAJORITY OF THE EXTENDED PERIOD...WITH THE EXCEPTION BEING THE THURSDAY/FRIDAY TIME FRAME. AT THE BEGINNING OF THE PERIOD...CONTINUED SOUTHERLY LL FLOW HELPS TO INCREASE LL MOISTURE ACROSS THE REGION. FORECAST MODELS CONTINUE TO SHOW SOME LIGHT QPF OVER OUR WEST AND NORTHWEST COUNTIES AND WOULD EXPECT CLOUDY SKIES WITH SOME PATCHY DRIZZLE AND LIGHT RAIN SUNDAY MAINLY WEST AND NORTH OF JACKSON. MOISTURE DEEPENS SUNDAY NIGHT INTO THE DAY ON MONDAY AS A COLD FRONT SAGS INTO THE AREA AND RAIN CHANCES INCREASE. PRECIP ASSOCIATED WITH THE FRONT APPEARS TO BE RAIN DURING MONDAY AFTERNOON/EVENING BEFORE POSSIBLY CHANGING TO A WINTRY MIX OR LIGHT SNOW BY TUESDAY MORNING...THOUGH THIS DEPENDS ON HOW QUICKLY THE FRONTAL PRECIP DROPS TO OUR SOUTH AND THE TIMING OF THE COLD AIR MASS MOVING INTO THE REGION. FORTUNATELY IT APPEARS THAT THE BULK OF THE PRECIP SHOULD BE TO OUR SOUTH BY THE TIME THE COLDER AIR MAKES IT IN. SOUTHERLY FLOW RETURNS POST-FRONTAL HELPING TO USHER IN WARMER TEMPS...LL MOISTURE... CLOUDS...AND SOME SHOWERS TUESDAY NIGHT AND WEDNESDAY. GFS APPEARS TO BE THE WETTER OF THE SOLUTIONS. HOWEVER... MODELS REALLY START TO DIVERGE IN THEIR SOLUTIONS WEDNESDAY SO FORECAST CONFIDENCE IS LOW FOR ANY SENSIBLE WEATHER FOR DAYS 6 AND 7. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1256 AM EST SAT NOV 29 2014 VFR CONDITIONS WILL LIKELY PERSIST THROUGH THE FORECAST PERIOD. THE BEST THREAT OF SOME MVFR CIGS CREEPING INTO THE AREA WILL BE LATE TONIGHT AS STRONG MOISTURE TRANSPORT BRINGS IN SOME SHALLOW MOISTURE. HOWEVER...AT THIS TIME...PLAN TO KEEP EVERYTHING VFR THROUGH TONIGHT. WILL BRING BACK SOME LOW LEVEL WIND SHEAR FOR THE REST OF THE NIGHT AND AGAIN TONIGHT AS STRONG INVERSIONS SET UP BOTH NIGHTS...WITH WINDS JUST OFF THE SURFACE OF 40 TO 45 KNOTS. WHILE THERE IS SOME UNCERTAINTY WITH THE MIXING HEIGHTS TODAY...A COMPROMISED SOLUTION WOULD STILL YIELD SOUTH/SOUTHWEST WINDS GUSTING TO 2O TO 30 MPH. I WOULDN`T BE SURPRISED TO SEE A FEW WIND GUSTS EVEN A BIT HIGHER THAN THIS. THIS WINDS SHOULD PICK UP BY MID TO LATE MORNING AND PERSIST THROUGH MID AFTERNOON...BEFORE SUBSIDING AGAIN THIS EVENING. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KAS SHORT TERM...SHALLENBERGER LONG TERM...JVM AVIATION...KAS
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1001 PM CST SUN NOV 30 2014 .DISCUSSION... SOME CHANGES WERE NECESSARY OVERNIGHT AS WELL AS MONDAY GIVEN A SLIGHTLY FASTER FRONTAL MOVEMENT. THE LEADING EDGE OF MUCH COLDER AIR IN THE FORM OF A STRONG COLD FRONT WAS LOCATED NEAR A HRO...FSM...DUA...RPH LINE AS OF 03Z. A 20 TO 25 DEGREE TEMPERATURE DROP EXISTS DIRECTLY BEHIND THIS BOUNDARY WHICH WAS OUTPACING OUR PREVIOUS FORECAST SLIGHTLY. THE OUACHITAS WILL LIKELY SLOW THIS BOUNDARY UP SLIGHTLY BUT STILL FEEL LIKE THE FASTER FRONTAL MOVEMENT VIA THE HRRR WARRANTED AN UPDATE THIS EVENING. CLOUD COVER IS PATCHY ATTM BUT SHOULD CONTINUE TO DEVELOP THROUGH THE OVERNIGHT HOURS AND THIS WILL BE CRUCIAL AS IT PERTAINS TO OVERNIGHT LOW TEMPERATURES...NOT TO MENTION JUST WHERE THE COLD FRONT IS EXPECTED TO BE BY 8 AM IN THE MORNING. BY 13Z...EXPECT THE FRONT TO BE NEAR OR JUST EAST OF A TYR...TO DEQ LINE...LIKELY BULGING OUT SLIGHTLY ACROSS THE NORTHERN HALF OF NE TX GIVEN THE BLOCKING INFLUENCE OF THE OUACHITAS. WINDS HAVE DECOUPLED PRETTY MUCH AREAWIDE THIS EVENING...BUT ESPECIALLY ACROSS OUR SE ZONES AND THIS IS WHERE PATCHY DENSE FOG WILL BECOME A POSSIBILITY IF THE CLOUD COVER TAKES ITS TIME IN FORMING. IF THIS FOG DEVELOPS...TEMPERATURES COULD FALL BELOW THEIR DEWPOINTS WHICH ALSO MAKES THIS A CHALLENGING FORECAST AS IT PERTAINS TO OVERNIGHT MIN TEMPS. RAISED TEMPERATURES SLIGHTLY ALONG A LFK...SHV...ELD LINE BUT COOLED TEMPERATURES JUST WEST OF THIS LINE AS THIS IS WHERE THE COLD FRONT IS EXPECTED TO BE BY 8 AM MON. COLD FRONT WILL LIKELY SLOW UP A BIT AS IT MOVES THROUGH NORTHERN LA ON MONDAY BUT STILL FEEL LIKE MAX TEMPS WILL BE REACHED DURING THE MORNING HOURS MONDAY GIVEN THE STRONG COLD AIR ADVECTION BEHIND THE FRONT. HAVING SAID THIS...ALSO UPDATED HOURLY DAYTIME TEMPERATURES TO BETTER REFLECT THE FALLING DAYTIME TEMPERATURES. DID NOT MAKE MUCH IN THE WAY OF CHANGES TO POP OVERNIGHT/MONDAY AS THE HRRR IS IN GOOD AGREEMENT WITH SOME PREFRONTAL/FRONTAL AND POST FRONTAL RAIN/SHOWERS DEVELOPING LATER TONIGHT AND THROUGH THE DAY MONDAY. UPDATED ZONE PACKAGE ALREADY SENT...13 && .PREV DISCUSSION... /ISSUED 652 PM CST SUN NOV 30 2014/ AVIATION... FOR THE 01/00Z TAFS...LOW CLOUDS WILL CONTINUE TO MOVE IN THE REGION FROM SW...BUT VFR CONDITIONS WILL REMAIN AT ALL SITES THROUGH THE EVENING. CIGS AND VISIBILITIES WILL LOWER OVERNIGHT CREATING POSSIBLE MVFR/IFR CONDITIONS AS PATCHY FOG WILL BE POSSIBLE AT MLU/SHV/LFK. A COLD FRONT WILL APPROACH THE AREA NEAR DAYBREAK. SHWRS ARE EXPECTED ALONG THE FRONT. WINDS WILL REMAIN FROM THE SOUTH BETWEEN 5-10 KTS OVERNIGHT...BUT WILL SHIFT TO THE NW FOLLOWING FRONTAL PASSAGE. 20 && .PRELIMINARY POINT TEMPS/POPS... SHV 61 63 38 52 47 / 20 60 30 0 10 MLU 60 73 40 53 45 / 20 60 40 10 10 DEQ 49 50 32 48 42 / 40 60 10 0 20 TXK 57 57 34 49 44 / 40 60 20 0 20 ELD 60 60 36 49 44 / 20 70 30 0 10 TYR 55 56 32 50 47 / 30 50 10 0 20 GGG 60 60 34 51 48 / 30 60 20 0 20 LFK 63 63 37 54 48 / 20 50 30 0 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 13
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1220 PM EST SAT NOV 29 2014 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 328 AM EST SAT NOV 29 2014 LIGHT SNOW/FREEZING RAIN WILL CHANGE TO LIGHT RAIN AND DIMINISH TODAY AS A WARM FRONT PUSHES NORTH THROUGH THE STATE. A MILD DAY IS EXPECTED TODAY AND MUCH OF SUNDAY BEFORE A STRONG COLD FRONT MOVES THROUGH AND DROPS HIGHS INTO THE MID 20S BY MONDAY. TEMPERATURES WILL CLIMB TO THE MID 30S BY THE MIDDLE OF NEXT WEEK. SOME DRIZZLE IS POSSIBLE TONIGHT AND SUNDAY AND THEN LIGHT SNOW MONDAY. && .UPDATE... ISSUED AT 1155 AM EST SAT NOV 29 2014 ANOTHER QUICK UPDATE TO BE MORE OPTIMISTIC WITH SKY COVER AS WARM FRONTAL MID CLOUDS CONTINUE LIFTING NORTH. MOSTLY SUNNY NOW EXPECTED UNTIL STRATUS ARRIVES LATER IN THE DAY FROM THE SOUTH. UPDATE ISSUED AT 958 AM EST SAT NOV 29 2014 ISSUED AN UPDATE TO GO WITH A DRY FORECAST UNTIL LATE THIS AFTERNOON AT THE EARLIEST. CURRENTLY THERE IS JUST SOME MID AND HIGH LEVEL CLOUDINESS PRESENT AND OUR ONLY CHANCE OF PRECIP WOULD BE FROM LIGHT DRIZZLE WITH THE STRATUS DECK WHICH IS EXPECTED TO ARRIVE/EXPAND FROM THE SOUTH LATER THIS AFTERNOON AND THIS EVENING. WE ACTUALLY HAVE A DECENT SHOT AT SEEING SOME PEEKS OF SUNSHINE TODAY BEFORE THE STRATUS DECK MOVES IN LATER... WHICH HAS BEEN A RARITY OF LATE. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 328 AM EST SAT NOV 29 2014 FORECAST CONCERNS DEAL WITH PCPN TRENDS THROUGH THE PERIOD. THE ONGOING WARM AIR ADVECTION PCPN HAS UNDERPERFORMED SO FAR AND HAS DECREASED IN COVERAGE AND INTENSITY SINCE IT MOVED ACROSS THE LAKE FROM WISCONSIN. MOST OF THE PCPN HAS BEEN LIGHT SNOW BUT THERE HAVE BEEN PATCHES OF LIGHT FZRA AND SLEET. LATEST HRRR SHOWS THE PCPN MOVING EAST OF THE CWA PRIOR TO 6AM. DECIDED TO CANCEL THE WINTER WX ADVISORY EARLY AS IMPACT FROM WHAT/S LEFT OF THE PCPN SHOULD BE MINIMAL. MODELS SHOW A WEAK DISTURBANCE MOVING THROUGH THIS AFTERNOON IN ZONAL FLOW. NOT MUCH TOO IT BUT WILL KEEP A 20 POP FOR LIGHT RAIN IN THE GRIDS. BUFKIT SHOWS SOME LIFT IN THE CLOUD LAYER TONIGHT IN SOUTH FLOW. ADDED SOME DRIZZLE/LIGHT RAIN TO THE GRIDS FOR THIS. TEMPS WILL REMAIN ABOVE FREEZING TONIGHT SO ANY PCPN THAT FALLS WILL BE LIQUID. SUNDAY WILL ALSO BE MILD WITH HIGHS IN THE 40S. HOWEVER...A STRONG COLD FRONT WILL MOVE ACROSS THE CWA DURING THE AFTERNOON. H8 TEMPS FALL FROM +8C TO -5C BY LATE IN THE DAY. MOISTURE IS VERY SHALLOW THOUGH...LESS THAN 4K FT. THUS LAKE EFFECT SNOW WILL BE MINIMAL SUNDAY NIGHT/MONDAY. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 328 AM EST SAT NOV 29 2014 EXTENDED PERIOD WILL BE RELATIVELY TRANQUIL WITH NO BIG STORMS AND ONLY A FEW BOUTS OF LIGHT PRECIPITATION. SFC HIGH BRINGS FAIR WEATHER THROUGH TUESDAY THEN MOVES EAST WITH A COLD FRONT COMING THROUGH TUESDAY NIGHT. ANY PRECIP SHOULD BE LIGHT WITH ONLY LIGHT LAKE EFFECT SNOW SHOWERS TO FOLLOW AS INVERSION HEIGHTS FALL BELOW 5000 FEET. THURSDAY AND FRIDAY ARE QUESTION MARKS AS AN AREA OF ISENTROPIC UPGLIDE NORTH OF A SFC WARM FRONT ACROSS THE OHIO VALLEY MAY FOCUS SOME SNOW OR MIXED PRECIP REACHING THE SOUTHERN FORECAST AREA. WILL GO WITH SLIGHT CHANCE POPS TO COVER THIS FOR NOW AS MODELS ARE SHOWING LOTS OF TIMING/LOCATION INCONSISTENCY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1220 PM EST SAT NOV 29 2014 VFR TO START THE TAF PERIOD WITH AN MVFR STRATUS DECK IS LOOKING LIKE IT WILL DEVELOP AFTER 00Z AND REMAIN THROUGH THE END OF THE TAF PERIOD. WHEN THE DECK DEVELOPS IS STILL UNCERTAIN BUT AT THIS TIME IT LOOKS MORE LIKE 03Z OR AFTER. A FEW SPOTS OF DRIZZLE WILL BE POSSIBLE OVER LOWER MICHIGAN AFTER THE STRATUS BUILDS IN BUT CONFIDENCE IN THIS OCCURRING OVER A TAF SITE IS LOW. && .MARINE... ISSUED AT 328 AM EST SAT NOV 29 2014 EXTENDED THE SCA THROUGH SUNDAY NIGHT. SOUTH WINDS WILL GUST TO 20 TO 25 KNOTS TODAY/TONIGHT AND THEN SHIFT TO THE NORTHWEST SUNDAY AS A STRONG COLD FRONT MOVES THROUGH. && .HYDROLOGY... ISSUED AT 328 AM EST SAT NOV 29 2014 RIVER LEVELS ARE RECEDING AND WILL CONTINUE TO DO SO OVER THE WEEKEND AS LITTLE APPRECIABLE PCPN IS EXPECTED. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 7 AM EST MONDAY FOR LMZ844>849. && $$ UPDATE...MEADE SYNOPSIS...93 SHORT TERM...93 LONG TERM...OSTUNO AVIATION...MACZKO HYDROLOGY...93 MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1157 AM EST SAT NOV 29 2014 LATEST UPDATE... UPDATE .SYNOPSIS... ISSUED AT 328 AM EST SAT NOV 29 2014 LIGHT SNOW/FREEZING RAIN WILL CHANGE TO LIGHT RAIN AND DIMINISH TODAY AS A WARM FRONT PUSHES NORTH THROUGH THE STATE. A MILD DAY IS EXPECTED TODAY AND MUCH OF SUNDAY BEFORE A STRONG COLD FRONT MOVES THROUGH AND DROPS HIGHS INTO THE MID 20S BY MONDAY. TEMPERATURES WILL CLIMB TO THE MID 30S BY THE MIDDLE OF NEXT WEEK. SOME DRIZZLE IS POSSIBLE TONIGHT AND SUNDAY AND THEN LIGHT SNOW MONDAY. && .UPDATE... ISSUED AT 1155 AM EST SAT NOV 29 2014 ANOTHER QUICK UPDATE TO BE MORE OPTIMISTIC WITH SKY COVER AS WARM FRONTAL MID CLOUDS CONTINUE LIFTING NORTH. MOSTLY SUNNY NOW EXPECTED UNTIL STRATUS ARRIVES LATER IN THE DAY FROM THE SOUTH. UPDATE ISSUED AT 958 AM EST SAT NOV 29 2014 ISSUED AN UPDATE TO GO WITH A DRY FORECAST UNTIL LATE THIS AFTERNOON AT THE EARLIEST. CURRENTLY THERE IS JUST SOME MID AND HIGH LEVEL CLOUDINESS PRESENT AND OUR ONLY CHANCE OF PRECIP WOULD BE FROM LIGHT DRIZZLE WITH THE STRATUS DECK WHICH IS EXPECTED TO ARRIVE/EXPAND FROM THE SOUTH LATER THIS AFTERNOON AND THIS EVENING. WE ACTUALLY HAVE A DECENT SHOT AT SEEING SOME PEEKS OF SUNSHINE TODAY BEFORE THE STRATUS DECK MOVES IN LATER... WHICH HAS BEEN A RARITY OF LATE. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 328 AM EST SAT NOV 29 2014 FORECAST CONCERNS DEAL WITH PCPN TRENDS THROUGH THE PERIOD. THE ONGOING WARM AIR ADVECTION PCPN HAS UNDERPERFORMED SO FAR AND HAS DECREASED IN COVERAGE AND INTENSITY SINCE IT MOVED ACROSS THE LAKE FROM WISCONSIN. MOST OF THE PCPN HAS BEEN LIGHT SNOW BUT THERE HAVE BEEN PATCHES OF LIGHT FZRA AND SLEET. LATEST HRRR SHOWS THE PCPN MOVING EAST OF THE CWA PRIOR TO 6AM. DECIDED TO CANCEL THE WINTER WX ADVISORY EARLY AS IMPACT FROM WHAT/S LEFT OF THE PCPN SHOULD BE MINIMAL. MODELS SHOW A WEAK DISTURBANCE MOVING THROUGH THIS AFTERNOON IN ZONAL FLOW. NOT MUCH TOO IT BUT WILL KEEP A 20 POP FOR LIGHT RAIN IN THE GRIDS. BUFKIT SHOWS SOME LIFT IN THE CLOUD LAYER TONIGHT IN SOUTH FLOW. ADDED SOME DRIZZLE/LIGHT RAIN TO THE GRIDS FOR THIS. TEMPS WILL REMAIN ABOVE FREEZING TONIGHT SO ANY PCPN THAT FALLS WILL BE LIQUID. SUNDAY WILL ALSO BE MILD WITH HIGHS IN THE 40S. HOWEVER...A STRONG COLD FRONT WILL MOVE ACROSS THE CWA DURING THE AFTERNOON. H8 TEMPS FALL FROM +8C TO -5C BY LATE IN THE DAY. MOISTURE IS VERY SHALLOW THOUGH...LESS THAN 4K FT. THUS LAKE EFFECT SNOW WILL BE MINIMAL SUNDAY NIGHT/MONDAY. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 328 AM EST SAT NOV 29 2014 EXTENDED PERIOD WILL BE RELATIVELY TRANQUIL WITH NO BIG STORMS AND ONLY A FEW BOUTS OF LIGHT PRECIPITATION. SFC HIGH BRINGS FAIR WEATHER THROUGH TUESDAY THEN MOVES EAST WITH A COLD FRONT COMING THROUGH TUESDAY NIGHT. ANY PRECIP SHOULD BE LIGHT WITH ONLY LIGHT LAKE EFFECT SNOW SHOWERS TO FOLLOW AS INVERSION HEIGHTS FALL BELOW 5000 FEET. THURSDAY AND FRIDAY ARE QUESTION MARKS AS AN AREA OF ISENTROPIC UPGLIDE NORTH OF A SFC WARM FRONT ACROSS THE OHIO VALLEY MAY FOCUS SOME SNOW OR MIXED PRECIP REACHING THE SOUTHERN FORECAST AREA. WILL GO WITH SLIGHT CHANCE POPS TO COVER THIS FOR NOW AS MODELS ARE SHOWING LOTS OF TIMING/LOCATION INCONSISTENCY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 640 AM EST SAT NOV 29 2014 VFR CONDITIONS EXPECTED THIS MORNING BUT A STRATUS CLOUD DECK WITH BASES AROUND 2500 FEET AND TOPS AROUND 4000 FEET IS EXPECTED THIS AFTERNOON AND TONIGHT. WINDS WILL BE SOUTHEAST AROUND 10 KNOTS THIS MORNING GOING TO SOUTH SOUTHWEST THIS AFTERNOON WITH SOME GUSTS TO 20 KNOTS AT TIMES. && .MARINE... ISSUED AT 328 AM EST SAT NOV 29 2014 EXTENDED THE SCA THROUGH SUNDAY NIGHT. SOUTH WINDS WILL GUST TO 20 TO 25 KNOTS TODAY/TONIGHT AND THEN SHIFT TO THE NORTHWEST SUNDAY AS A STRONG COLD FRONT MOVES THROUGH. && .HYDROLOGY... ISSUED AT 328 AM EST SAT NOV 29 2014 RIVER LEVELS ARE RECEDING AND WILL CONTINUE TO DO SO OVER THE WEEKEND AS LITTLE APPRECIABLE PCPN IS EXPECTED. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 7 AM EST MONDAY FOR LMZ844>849. && $$ UPDATE...MEADE SYNOPSIS...93 SHORT TERM...93 LONG TERM...OSTUNO AVIATION...OSTUNO HYDROLOGY...93 MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1006 AM EST SAT NOV 29 2014 LATEST UPDATE... UPDATE .SYNOPSIS... ISSUED AT 328 AM EST SAT NOV 29 2014 LIGHT SNOW/FREEZING RAIN WILL CHANGE TO LIGHT RAIN AND DIMINISH TODAY AS A WARM FRONT PUSHES NORTH THROUGH THE STATE. A MILD DAY IS EXPECTED TODAY AND MUCH OF SUNDAY BEFORE A STRONG COLD FRONT MOVES THROUGH AND DROPS HIGHS INTO THE MID 20S BY MONDAY. TEMPERATURES WILL CLIMB TO THE MID 30S BY THE MIDDLE OF NEXT WEEK. SOME DRIZZLE IS POSSIBLE TONIGHT AND SUNDAY AND THEN LIGHT SNOW MONDAY. && .UPDATE... ISSUED AT 958 AM EST SAT NOV 29 2014 ISSUED AN UPDATE TO GO WITH A DRY FORECAST UNTIL LATE THIS AFTERNOON AT THE EARLIEST. CURRENTLY THERE IS JUST SOME MID AND HIGH LEVEL CLOUDINESS PRESENT AND OUR ONLY CHANCE OF PRECIP WOULD BE FROM LIGHT DRIZZLE WITH THE STRATUS DECK WHICH IS EXPECTED TO ARRIVE/EXPAND FROM THE SOUTH LATER THIS AFTERNOON AND THIS EVENING. WE ACTUALLY HAVE A DECENT SHOT AT SEEING SOME PEEKS OF SUNSHINE TODAY BEFORE THE STRATUS DECK MOVES IN LATER... WHICH HAS BEEN A RARITY OF LATE. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 328 AM EST SAT NOV 29 2014 FORECAST CONCERNS DEAL WITH PCPN TRENDS THROUGH THE PERIOD. THE ONGOING WARM AIR ADVECTION PCPN HAS UNDERPERFORMED SO FAR AND HAS DECREASED IN COVERAGE AND INTENSITY SINCE IT MOVED ACROSS THE LAKE FROM WISCONSIN. MOST OF THE PCPN HAS BEEN LIGHT SNOW BUT THERE HAVE BEEN PATCHES OF LIGHT FZRA AND SLEET. LATEST HRRR SHOWS THE PCPN MOVING EAST OF THE CWA PRIOR TO 6AM. DECIDED TO CANCEL THE WINTER WX ADVISORY EARLY AS IMPACT FROM WHAT/S LEFT OF THE PCPN SHOULD BE MINIMAL. MODELS SHOW A WEAK DISTURBANCE MOVING THROUGH THIS AFTERNOON IN ZONAL FLOW. NOT MUCH TOO IT BUT WILL KEEP A 20 POP FOR LIGHT RAIN IN THE GRIDS. BUFKIT SHOWS SOME LIFT IN THE CLOUD LAYER TONIGHT IN SOUTH FLOW. ADDED SOME DRIZZLE/LIGHT RAIN TO THE GRIDS FOR THIS. TEMPS WILL REMAIN ABOVE FREEZING TONIGHT SO ANY PCPN THAT FALLS WILL BE LIQUID. SUNDAY WILL ALSO BE MILD WITH HIGHS IN THE 40S. HOWEVER...A STRONG COLD FRONT WILL MOVE ACROSS THE CWA DURING THE AFTERNOON. H8 TEMPS FALL FROM +8C TO -5C BY LATE IN THE DAY. MOISTURE IS VERY SHALLOW THOUGH...LESS THAN 4K FT. THUS LAKE EFFECT SNOW WILL BE MINIMAL SUNDAY NIGHT/MONDAY. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 328 AM EST SAT NOV 29 2014 EXTENDED PERIOD WILL BE RELATIVELY TRANQUIL WITH NO BIG STORMS AND ONLY A FEW BOUTS OF LIGHT PRECIPITATION. SFC HIGH BRINGS FAIR WEATHER THROUGH TUESDAY THEN MOVES EAST WITH A COLD FRONT COMING THROUGH TUESDAY NIGHT. ANY PRECIP SHOULD BE LIGHT WITH ONLY LIGHT LAKE EFFECT SNOW SHOWERS TO FOLLOW AS INVERSION HEIGHTS FALL BELOW 5000 FEET. THURSDAY AND FRIDAY ARE QUESTION MARKS AS AN AREA OF ISENTROPIC UPGLIDE NORTH OF A SFC WARM FRONT ACROSS THE OHIO VALLEY MAY FOCUS SOME SNOW OR MIXED PRECIP REACHING THE SOUTHERN FORECAST AREA. WILL GO WITH SLIGHT CHANCE POPS TO COVER THIS FOR NOW AS MODELS ARE SHOWING LOTS OF TIMING/LOCATION INCONSISTENCY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 640 AM EST SAT NOV 29 2014 VFR CONDITIONS EXPECTED THIS MORNING BUT A STRATUS CLOUD DECK WITH BASES AROUND 2500 FEET AND TOPS AROUND 4000 FEET IS EXPECTED THIS AFTERNOON AND TONIGHT. WINDS WILL BE SOUTHEAST AROUND 10 KNOTS THIS MORNING GOING TO SOUTH SOUTHWEST THIS AFTERNOON WITH SOME GUSTS TO 20 KNOTS AT TIMES. && .MARINE... ISSUED AT 328 AM EST SAT NOV 29 2014 EXTENDED THE SCA THROUGH SUNDAY NIGHT. SOUTH WINDS WILL GUST TO 20 TO 25 KNOTS TODAY/TONIGHT AND THEN SHIFT TO THE NORTHWEST SUNDAY AS A STRONG COLD FRONT MOVES THROUGH. && .HYDROLOGY... ISSUED AT 328 AM EST SAT NOV 29 2014 RIVER LEVELS ARE RECEDING AND WILL CONTINUE TO DO SO OVER THE WEEKEND AS LITTLE APPRECIABLE PCPN IS EXPECTED. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 7 AM EST MONDAY FOR LMZ844>849. && $$ UPDATE...MEADE SYNOPSIS...93 SHORT TERM...93 LONG TERM...OSTUNO AVIATION...OSTUNO HYDROLOGY...93 MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
640 AM EST SAT NOV 29 2014 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 328 AM EST SAT NOV 29 2014 LIGHT SNOW/FREEZING RAIN WILL CHANGE TO LIGHT RAIN AND DIMINISH TODAY AS A WARM FRONT PUSHES NORTH THROUGH THE STATE. A MILD DAY IS EXPECTED TODAY AND MUCH OF SUNDAY BEFORE A STRONG COLD FRONT MOVES THROUGH AND DROPS HIGHS INTO THE MID 20S BY MONDAY. TEMPERATURES WILL CLIMB TO THE MID 30S BY THE MIDDLE OF NEXT WEEK. SOME DRIZZLE IS POSSIBLE TONIGHT AND SUNDAY AND THEN LIGHT SNOW MONDAY. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 328 AM EST SAT NOV 29 2014 FORECAST CONCERNS DEAL WITH PCPN TRENDS THROUGH THE PERIOD. THE ONGOING WARM AIR ADVECTION PCPN HAS UNDERPERFORMED SO FAR AND HAS DECREASED IN COVERAGE AND INTENSITY SINCE IT MOVED ACROSS THE LAKE FROM WISCONSIN. MOST OF THE PCPN HAS BEEN LIGHT SNOW BUT THERE HAVE BEEN PATCHES OF LIGHT FZRA AND SLEET. LATEST HRRR SHOWS THE PCPN MOVING EAST OF THE CWA PRIOR TO 6AM. DECIDED TO CANCEL THE WINTER WX ADVISORY EARLY AS IMPACT FROM WHAT/S LEFT OF THE PCPN SHOULD BE MINIMAL. MODELS SHOW A WEAK DISTURBANCE MOVING THROUGH THIS AFTERNOON IN ZONAL FLOW. NOT MUCH TOO IT BUT WILL KEEP A 20 POP FOR LIGHT RAIN IN THE GRIDS. BUFKIT SHOWS SOME LIFT IN THE CLOUD LAYER TONIGHT IN SOUTH FLOW. ADDED SOME DRIZZLE/LIGHT RAIN TO THE GRIDS FOR THIS. TEMPS WILL REMAIN ABOVE FREEZING TONIGHT SO ANY PCPN THAT FALLS WILL BE LIQUID. SUNDAY WILL ALSO BE MILD WITH HIGHS IN THE 40S. HOWEVER...A STRONG COLD FRONT WILL MOVE ACROSS THE CWA DURING THE AFTERNOON. H8 TEMPS FALL FROM +8C TO -5C BY LATE IN THE DAY. MOISTURE IS VERY SHALLOW THOUGH...LESS THAN 4K FT. THUS LAKE EFFECT SNOW WILL BE MINIMAL SUNDAY NIGHT/MONDAY. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 328 AM EST SAT NOV 29 2014 EXTENDED PERIOD WILL BE RELATIVELY TRANQUIL WITH NO BIG STORMS AND ONLY A FEW BOUTS OF LIGHT PRECIPITATION. SFC HIGH BRINGS FAIR WEATHER THROUGH TUESDAY THEN MOVES EAST WITH A COLD FRONT COMING THROUGH TUESDAY NIGHT. ANY PRECIP SHOULD BE LIGHT WITH ONLY LIGHT LAKE EFFECT SNOW SHOWERS TO FOLLOW AS INVERSION HEIGHTS FALL BELOW 5000 FEET. THURSDAY AND FRIDAY ARE QUESTION MARKS AS AN AREA OF ISENTROPIC UPGLIDE NORTH OF A SFC WARM FRONT ACROSS THE OHIO VALLEY MAY FOCUS SOME SNOW OR MIXED PRECIP REACHING THE SOUTHERN FORECAST AREA. WILL GO WITH SLIGHT CHANCE POPS TO COVER THIS FOR NOW AS MODELS ARE SHOWING LOTS OF TIMING/LOCATION INCONSISTENCY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 640 AM EST SAT NOV 29 2014 VFR CONDITIONS EXPECTED THIS MORNING BUT A STRATUS CLOUD DECK WITH BASES AROUND 2500 FEET AND TOPS AROUND 4000 FEET IS EXPECTED THIS AFTERNOON AND TONIGHT. WINDS WILL BE SOUTHEAST AROUND 10 KNOTS THIS MORNING GOING TO SOUTH SOUTHWEST THIS AFTERNOON WITH SOME GUSTS TO 20 KNOTS AT TIMES. && .MARINE... ISSUED AT 328 AM EST SAT NOV 29 2014 EXTENDED THE SCA THROUGH SUNDAY NIGHT. SOUTH WINDS WILL GUST TO 20 TO 25 KNOTS TODAY/TONIGHT AND THEN SHIFT TO THE NORTHWEST SUNDAY AS A STRONG COLD FRONT MOVES THROUGH. && .HYDROLOGY... ISSUED AT 328 AM EST SAT NOV 29 2014 RIVER LEVELS ARE RECEDING AND WILL CONTINUE TO DO SO OVER THE WEEKEND AS LITTLE APPRECIABLE PCPN IS EXPECTED. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 7 AM EST MONDAY FOR LMZ844>849. && $$ SYNOPSIS...93 SHORT TERM...93 LONG TERM...OSTUNO AVIATION...OSTUNO HYDROLOGY...93 MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
328 AM EST SAT NOV 29 2014 LATEST UPDATE... SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE .SYNOPSIS... ISSUED AT 328 AM EST SAT NOV 29 2014 LIGHT SNOW/FREEZING RAIN WILL CHANGE TO LIGHT RAIN AND DIMINISH TODAY AS A WARM FRONT PUSHES NORTH THROUGH THE STATE. A MILD DAY IS EXPECTED TODAY AND MUCH OF SUNDAY BEFORE A STRONG COLD FRONT MOVES THROUGH AND DROPS HIGHS INTO THE MID 20S BY MONDAY. TEMPERATURES WILL CLIMB TO THE MID 30S BY THE MIDDLE OF NEXT WEEK. SOME DRIZZLE IS POSSIBLE TONIGHT AND SUNDAY AND THEN LIGHT SNOW MONDAY. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 328 AM EST SAT NOV 29 2014 FORECAST CONCERNS DEAL WITH PCPN TRENDS THROUGH THE PERIOD. THE ONGOING WARM AIR ADVECTION PCPN HAS UNDERPERFORMED SO FAR AND HAS DECREASED IN COVERAGE AND INTENSITY SINCE IT MOVED ACROSS THE LAKE FROM WISCONSIN. MOST OF THE PCPN HAS BEEN LIGHT SNOW BUT THERE HAVE BEEN PATCHES OF LIGHT FZRA AND SLEET. LATEST HRRR SHOWS THE PCPN MOVING EAST OF THE CWA PRIOR TO 6AM. DECIDED TO CANCEL THE WINTER WX ADVISORY EARLY AS IMPACT FROM WHAT/S LEFT OF THE PCPN SHOULD BE MINIMAL. MODELS SHOW A WEAK DISTURBANCE MOVING THROUGH THIS AFTERNOON IN ZONAL FLOW. NOT MUCH TOO IT BUT WILL KEEP A 20 POP FOR LIGHT RAIN IN THE GRIDS. BUFKIT SHOWS SOME LIFT IN THE CLOUD LAYER TONIGHT IN SOUTH FLOW. ADDED SOME DRIZZLE/LIGHT RAIN TO THE GRIDS FOR THIS. TEMPS WILL REMAIN ABOVE FREEZING TONIGHT SO ANY PCPN THAT FALLS WILL BE LIQUID. SUNDAY WILL ALSO BE MILD WITH HIGHS IN THE 40S. HOWEVER...A STRONG COLD FRONT WILL MOVE ACROSS THE CWA DURING THE AFTERNOON. H8 TEMPS FALL FROM +8C TO -5C BY LATE IN THE DAY. MOISTURE IS VERY SHALLOW THOUGH...LESS THAN 4K FT. THUS LAKE EFFECT SNOW WILL BE MINIMAL SUNDAY NIGHT/MONDAY. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 328 AM EST SAT NOV 29 2014 EXTENDED PERIOD WILL BE RELATIVELY TRANQUIL WITH NO BIG STORMS AND ONLY A FEW BOUTS OF LIGHT PRECIPITATION. SFC HIGH BRINGS FAIR WEATHER THROUGH TUESDAY THEN MOVES EAST WITH A COLD FRONT COMING THROUGH TUESDAY NIGHT. ANY PRECIP SHOULD BE LIGHT WITH ONLY LIGHT LAKE EFFECT SNOW SHOWERS TO FOLLOW AS INVERSION HEIGHTS FALL BELOW 5000 FEET. THURSDAY AND FRIDAY ARE QUESTION MARKS AS AN AREA OF ISENTROPIC UPGLIDE NORTH OF A SFC WARM FRONT ACROSS THE OHIO VALLEY MAY FOCUS SOME SNOW OR MIXED PRECIP REACHING THE SOUTHERN FORECAST AREA. WILL GO WITH SLIGHT CHANCE POPS TO COVER THIS FOR NOW AS MODELS ARE SHOWING LOTS OF TIMING/LOCATION INCONSISTENCY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1200 AM EST SAT NOV 29 2014 A BATCH OF MIXED PRECIPITATION IS STILL FORECAST TO SWING THROUGH THE TAF SITES BEFORE DAYBREAK. SNOW SHOULD MIX WITH A BIT OF SLEET AND LIGHT FREEZING RAIN BEFORE ENDING BY 10Z TO 11Z THIS MORNING. NOT EXPECTING BIG REDUCTIONS TO VISIBILITY OR LONG PERIODS OF PRECIPITATION...AS IT WILL BE SOMEWHAT SHOWERY IN NATURE. CEILINGS HAVE TRENDED UP THIS EVENING WITH KMKG AND KGRR THE ONLY TAF SITES STILL REPORTING A MVFR CEILING. EXPECTING CEILINGS TO CONTINUE TO RISE TONIGHT WITH ALL SITES BECOMING VFR BY DAYBREAK. SATURDAY MORNING SHOULD BE VFR AT ALL SITES BEFORE TRENDING BACK TO MVFR IN THE AFTERNOON AND EVENING WITH SOME LIGHT DRIZZLE. WINDS WILL BE SOUTHERLY THE NEXT 24 HOURS...BECOMING A BIT GUSTY SATURDAY AFTERNOON. GUSTS SATURDAY AFTERNOON AROUND 20 KNOTS ARE POSSIBLE. && .MARINE... ISSUED AT 328 AM EST SAT NOV 29 2014 EXTENDED THE SCA THROUGH SUNDAY NIGHT. SOUTH WINDS WILL GUST TO 20 TO 25 KNOTS TODAY/TONIGHT AND THEN SHIFT TO THE NORTHWEST SUNDAY AS A STRONG COLD FRONT MOVES THROUGH. && .HYDROLOGY... ISSUED AT 328 AM EST SAT NOV 29 2014 RIVER LEVELS ARE RECEDING AND WILL CONTINUE TO DO SO OVER THE WEEKEND AS LITTLE APPRECIABLE PCPN IS EXPECTED. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 7 AM EST MONDAY FOR LMZ844>849. && $$ SYNOPSIS...93 SHORT TERM...93 LONG TERM...OSTUNO AVIATION...DUKE HYDROLOGY...93 MARINE...93
AREA FORECAST DISCUSSION
NWS DULUTH MN
1140 AM CST SAT NOV 29 2014 .UPDATE... ISSUED AT 1139 CST SAT NOV 29 2014 QUICK UPDATE TO SLIGHTLY CHANGE WEATHER GRIDS TO BETTER REFLECT GROUND TRUTH REPORTS THIS MORNING. MOST PRECIP ACROSS THE NORTHERN IRON RANGE AND ARROWHEAD REGION HAS BEEN LIGHT FREEZING RAIN...CAUSING A GLAZE OF ICE ON ELEVATED SURFACES. HAD A QUICK MOVING LIGHT TO MODERATE AREA OF FREEZING RAIN MOVE THROUGH EARLIER THIS MORNING FOR WHICH A SPECIAL WX STATEMENT WAS ISSUED...AND MAY RE-ISSUE AS OCCASIONAL LIGHT FREEZING RAIN AND FREEZING DRIZZLE CONTINUE TO AFFECT THE AREA THIS MORNING. 12Z INL SOUNDING AND RAP ANALYSIS DEPICTED A WARM LAYER ALOFT WHICH SUPPORTED A MIX OF SLEET AND FREEZING RAIN/DRIZZLE...AND OBSERVATIONS/SPOTTER REPORTS THIS MORNING HAVE SUGGESTED MOST PRECIP IS FALLING AS LIGHT FREEZING RAIN/DRIZZLE. STILL KEPT A MENTION FOR SLEET IN AS COLD AIR MOVES IN FROM THE NORTHWEST LATE THIS AFTERNOON BEFORE ALL PRECIP CHANGES TO SNOW TONIGHT. ALSO UPDATED AVIATION DISCUSSION BELOW FOR THE 18Z TAF ISSUANCE. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CST SAT NOV 29 2014 AT 330 AM...TEMPERATURES CONTINUED TO RISE ACROSS THE NORTHLAND. TEMPERATURES WERE GENERALLY IN THE UPPER TEENS TO LOWER 20S ACROSS THE REGION. SCATTERED PRECIPITATION WAS FOUND ACROSS THE AREA...ESPECIALLY ACROSS THE ARROWHEAD. THE PRECIPITATION WAS GENERALLY A MIXED BAG...WITH SOME SPOTTY FREEZING RAIN...SLEET AND SNOW. HAVE NOT SEEN MUCH IN THE WAY OF STRATUS AND FOG DEVELOPMENT AT THIS POINT. THE MAIN FOCUS FOR TODAY WILL BE THE CONTINUED THREAT OF MIXED PRECIPITATION ACROSS THE NORTHLAND. MODEL GUIDANCE GENERALLY INDICATES THE THREAT FOR MIXED FZRA/SLEET AND SNOW WILL BE ACROSS THE NORTH...AND THAT THE THREAT WILL DECREASE AS THE DAY WEARS ON. CANADIAN AND U.S. RADARS SHOWED THE MOST SUBSTANTIAL PRECIPITATION SLIDING ALONG AND NORTH OF THE INTERNATIONAL BORDER...SPREADING INTO FAR NW MN. A WEAK SURFACE LOW PRESSURE SYSTEM AND TRAILING COLD FRONT WILL MOVE ACROSS THE AREA TODAY. STILL SOME QUESTION AS TO HOW HIGH TEMPS WILL GO TODAY. THINK THERE WILL BE CONSIDERABLE CLOUD COVER...SO DID PULL BACK A FEW DEGREES FOR MOST PLACES. CONTEMPLATED ADDING MENTION OF FREEZING DRIZZLE OR DRIZZLE BUT WILL CONTINUE TO MONITOR. THE FRONT WILL CONTINUE TO MOVE SOUTH AND EAST ACROSS THE WESTERN GREAT LAKES TONIGHT. TEMPERATURES COULD FALL TO THE SINGLE DIGITS BELOW ZERO IN NORTH CENTRAL MINNESOTA BY LATE TONIGHT. GUSTY NORTHWEST WINDS WILL PERSIST BEHIND THE COLD FRONT DUE TO STRONG CAA AND EFFECTIVE MOMENTUM TRANSFER. SUNDAY WILL BE VERY COLD WITH GRADUALLY CLEARING SKIES. HIGHS WILL NOT CLIMB MUCH FROM OVERNIGHT LOWS TONIGHT DUE TO STRONG CAA VERY COLD H85 TEMPS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 345 AM CST SAT NOV 29 2014 THE NORTHLAND WILL GET A BLAST OF ARCTIC AIR SUNDAY NIGHT AND EARLY MONDAY AS AN UPPER LOW MOVES THROUGH MANITOBA AND NORTHERN ONTARIO. FAR NORTHERN MINNESOTA WILL SEE 850 HPA TEMPERATURES DROP TO WHAT IS LIKELY THE COLDEST TEMPERATURES SEEN IN THE NORTHLAND THIS SEASON UP TO NOW...ABOUT 28 TO 30 DEGREES BELOW ZERO. THE STRONG COLD AIR ADVECTION COULD BRING GUSTY WINDS. THE NAM12 SOUNDINGS SUGGEST A MIXING LAYER THAT COULD BRING GUSTS UP TO AROUND 30 KNOTS. TEMPERATURES WILL LIKELY PLUMMET TO WELL BELOW ZERO BY MONDAY MORNING. FAR NORTHERN MINNESOTA SHOULD SEE LOWS IN THE TEENS TO 20S BELOW ZERO. THE COMBINATION OF THE WINDS AND COLD TEMPERATURES WILL LIKELY RESULT IN WIDESPREAD WIND CHILLS OF 25 TO 40 DEGREES BELOW ZERO. WE MIGHT NEED TO CONSIDER A WIND CHILL WATCH FOR THE BORDERLAND REGION SINCE THE WIND CHILLS FLIRT WITH 40 TO 45 DEGREES BELOW ZERO. THE BLAST OF COLD AIR WILL INCREASE CHANCES OF LAKE EFFECT SNOW OVER NW WISCONSIN. HOWEVER...THE MORE WNW WIND DIRECTION AND LOW HUMIDITY WILL LIKELY PREVENT ANY SIGNIFICANT SNOW ACCUMULATIONS IN NW WISCONSIN. HIGH PRESSURE WILL MOVE INTO THE UPPER MIDWEST AND NORTHLAND MONDAY...PROVIDING THE NORTHLAND WITH A COLD BUT SUNNY DAY. THERE WILL BE ANOTHER COLD FRONT PASSAGE TUESDAY AND TUESDAY NIGHT WHICH COULD BRING LIGHT SNOW TO THE FORECAST AREA. HIGH PRESSURE WILL MOVE THROUGH THE REGION AGAIN WEDNESDAY. SOUTHERLY FLOW WILL DEVELOP THURSDAY IN THE WAKE OF THE PASSING HIGH PRESSURE...AND THE UPPER LEVEL FLOW WILL BECOME MORE ZONAL. THIS WILL LEAD TO A LATE WEEK WARMING TREND. THERE ARE LOW CHANCES OF SNOW DURING THE LATE WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1139 AM CST SAT NOV 29 2014 TAF SITES WILL REMAIN WITHIN THE SURFACE WARM SECTOR FOR ANOTHER FEW HOURS THIS AFTERNOON IN ADVANCE OF STRONG ARCTIC COLD FRONT AS S/W TROF CONTINUES TO ADVANCE EASTWARD INTO ONTARIO. MVFR/IFR CEILINGS AND MVFR VSBYS WILL PERSIST IN MOST LOCALES IN FOG..AND PERHAPS SOME -FZDZ. MIXED PRECIP WILL BE A BIT MORE SUBSTANTIAL AT KINL FOR A COUPLE OF HOURS IN CLOSER PROXIMITY TO STRONGER DEEP LAYER FORCING FOR ASCENT AND MOISTURE. COLD FRONT WILL ADVANCE RAPIDLY SOUTHEASTWARD LATE THIS AFTERNOON/EVENING SWITCHING WINDS TO THE WNW..AND CHANGING ALL PRECIP BACK OVER TO LIGHT SNOW/SNOW SHOWERS. SNOW SHOWERS AND FLURRIES ARE LIKELY TO PERSIST WELL INTO SUNDAY MORNING AT MOST LOCALES WITH STRONG LOW LEVEL COLD ADVECTION..ALTHOUGH VISIBILITY RESTRICTIONS SHOULD NOT BE SUBSTANTIAL. && .PRELIMINARY POINT TEMPS/POPS... DLH 32 8 12 -11 / 30 20 10 0 INL 26 -3 5 -22 / 60 20 10 10 BRD 33 6 10 -12 / 10 10 10 0 HYR 36 12 16 -9 / 20 10 10 10 ASX 36 15 18 -6 / 20 20 30 20 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ UPDATE...JJM SHORT TERM...DAP LONG TERM...GROCHOCINSKI AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS DULUTH MN
1119 AM CST SAT NOV 29 2014 .UPDATE... ISSUED AT 1119 CST SAT NOV 29 2014 QUICK UPDATE TO SLIGHTLY CHANGE WEATHER GRIDS TO BETTER REFLECT GROUND TRUTH REPORTS THIS MORNING. MOST PRECIP ACROSS THE NORTHERN IRON RANGE AND ARROWHEAD REGION HAS BEEN LIGHT FREEZING RAIN...CAUSING A GLAZE OF ICE ON ELEVATED SURFACES. HAD A QUICK MOVING LIGHT TO MODERATE AREA OF FREEZING RAIN MOVE THROUGH EARLIER THIS MORNING FOR WHICH A SPECIAL WX STATEMENT WAS ISSUED...AND MAY RE-ISSUE AS OCCASIONAL LIGHT FREEZING RAIN AND FREEZING DRIZZLE CONTINUE TO AFFECT THE AREA THIS MORNING. 12Z INL SOUNDING AND RAP ANALYSIS DEPICTED A WARM LAYER ALOFT WHICH SUPPORTED A MIX OF SLEET AND FREEZING RAIN/DRIZZLE...AND OBSERVATIONS/SPOTTER REPORTS THIS MORNING HAVE SUGGESTED MOST PRECIP IS FALLING AS LIGHT FREEZING RAIN/DRIZZLE. STILL KEPT A MENTION FOR SLEET IN AS COLD AIR MOVES IN FROM THE NORTHWEST LATE THIS AFTERNOON BEFORE ALL PRECIP CHANGES TO SNOW TONIGHT. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CST SAT NOV 29 2014 AT 330 AM...TEMPERATURES CONTINUED TO RISE ACROSS THE NORTHLAND. TEMPERATURES WERE GENERALLY IN THE UPPER TEENS TO LOWER 20S ACROSS THE REGION. SCATTERED PRECIPITATION WAS FOUND ACROSS THE AREA...ESPECIALLY ACROSS THE ARROWHEAD. THE PRECIPITATION WAS GENERALLY A MIXED BAG...WITH SOME SPOTTY FREEZING RAIN...SLEET AND SNOW. HAVE NOT SEEN MUCH IN THE WAY OF STRATUS AND FOG DEVELOPMENT AT THIS POINT. THE MAIN FOCUS FOR TODAY WILL BE THE CONTINUED THREAT OF MIXED PRECIPITATION ACROSS THE NORTHLAND. MODEL GUIDANCE GENERALLY INDICATES THE THREAT FOR MIXED FZRA/SLEET AND SNOW WILL BE ACROSS THE NORTH...AND THAT THE THREAT WILL DECREASE AS THE DAY WEARS ON. CANADIAN AND U.S. RADARS SHOWED THE MOST SUBSTANTIAL PRECIPITATION SLIDING ALONG AND NORTH OF THE INTERNATIONAL BORDER...SPREADING INTO FAR NW MN. A WEAK SURFACE LOW PRESSURE SYSTEM AND TRAILING COLD FRONT WILL MOVE ACROSS THE AREA TODAY. STILL SOME QUESTION AS TO HOW HIGH TEMPS WILL GO TODAY. THINK THERE WILL BE CONSIDERABLE CLOUD COVER...SO DID PULL BACK A FEW DEGREES FOR MOST PLACES. CONTEMPLATED ADDING MENTION OF FREEZING DRIZZLE OR DRIZZLE BUT WILL CONTINUE TO MONITOR. THE FRONT WILL CONTINUE TO MOVE SOUTH AND EAST ACROSS THE WESTERN GREAT LAKES TONIGHT. TEMPERATURES COULD FALL TO THE SINGLE DIGITS BELOW ZERO IN NORTH CENTRAL MINNESOTA BY LATE TONIGHT. GUSTY NORTHWEST WINDS WILL PERSIST BEHIND THE COLD FRONT DUE TO STRONG CAA AND EFFECTIVE MOMENTUM TRANSFER. SUNDAY WILL BE VERY COLD WITH GRADUALLY CLEARING SKIES. HIGHS WILL NOT CLIMB MUCH FROM OVERNIGHT LOWS TONIGHT DUE TO STRONG CAA VERY COLD H85 TEMPS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 345 AM CST SAT NOV 29 2014 THE NORTHLAND WILL GET A BLAST OF ARCTIC AIR SUNDAY NIGHT AND EARLY MONDAY AS AN UPPER LOW MOVES THROUGH MANITOBA AND NORTHERN ONTARIO. FAR NORTHERN MINNESOTA WILL SEE 850 HPA TEMPERATURES DROP TO WHAT IS LIKELY THE COLDEST TEMPERATURES SEEN IN THE NORTHLAND THIS SEASON UP TO NOW...ABOUT 28 TO 30 DEGREES BELOW ZERO. THE STRONG COLD AIR ADVECTION COULD BRING GUSTY WINDS. THE NAM12 SOUNDINGS SUGGEST A MIXING LAYER THAT COULD BRING GUSTS UP TO AROUND 30 KNOTS. TEMPERATURES WILL LIKELY PLUMMET TO WELL BELOW ZERO BY MONDAY MORNING. FAR NORTHERN MINNESOTA SHOULD SEE LOWS IN THE TEENS TO 20S BELOW ZERO. THE COMBINATION OF THE WINDS AND COLD TEMPERATURES WILL LIKELY RESULT IN WIDESPREAD WIND CHILLS OF 25 TO 40 DEGREES BELOW ZERO. WE MIGHT NEED TO CONSIDER A WIND CHILL WATCH FOR THE BORDERLAND REGION SINCE THE WIND CHILLS FLIRT WITH 40 TO 45 DEGREES BELOW ZERO. THE BLAST OF COLD AIR WILL INCREASE CHANCES OF LAKE EFFECT SNOW OVER NW WISCONSIN. HOWEVER...THE MORE WNW WIND DIRECTION AND LOW HUMIDITY WILL LIKELY PREVENT ANY SIGNIFICANT SNOW ACCUMULATIONS IN NW WISCONSIN. HIGH PRESSURE WILL MOVE INTO THE UPPER MIDWEST AND NORTHLAND MONDAY...PROVIDING THE NORTHLAND WITH A COLD BUT SUNNY DAY. THERE WILL BE ANOTHER COLD FRONT PASSAGE TUESDAY AND TUESDAY NIGHT WHICH COULD BRING LIGHT SNOW TO THE FORECAST AREA. HIGH PRESSURE WILL MOVE THROUGH THE REGION AGAIN WEDNESDAY. SOUTHERLY FLOW WILL DEVELOP THURSDAY IN THE WAKE OF THE PASSING HIGH PRESSURE...AND THE UPPER LEVEL FLOW WILL BECOME MORE ZONAL. THIS WILL LEAD TO A LATE WEEK WARMING TREND. THERE ARE LOW CHANCES OF SNOW DURING THE LATE WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 546 AM CST SAT NOV 29 2014 WIDESPREAD IFR/MVFR CIGS ARE EXPECTED OVER NE MINNESOTA AND NW WISCONSIN THROUGH TONIGHT. A LOW PRESSURE SYSTEM IN THE DAKOTAS WILL MOVE THROUGH NORTHERN MINNESOTA THIS MORNING AND INTO NW ONTARIO THIS AFTERNOON. THERE COULD BE LIGHT SLEET AND SNOW OVER NORTHERN MINNESOTA THROUGH THIS AFTERNOON. A COLD FRONT WILL MOVE THROUGH THE NORTHLAND LATE THIS AFTERNOON AND EARLY THIS EVENING. GUSTY NORTHWEST WINDS WILL DEVELOP IN ITS WAKE. && .PRELIMINARY POINT TEMPS/POPS... DLH 32 8 12 -11 / 30 20 10 0 INL 26 -3 5 -22 / 60 20 10 10 BRD 33 6 10 -12 / 10 10 10 0 HYR 36 12 16 -9 / 20 10 10 10 ASX 36 15 18 -6 / 20 20 30 20 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ UPDATE...JJM SHORT TERM...DAP LONG TERM...GROCHOCINSKI AVIATION...GROCHOCINSKI
AREA FORECAST DISCUSSION
NWS JACKSON MS
342 PM CST SAT NOV 29 2014 .DISCUSSION...A MILD AND BREEZY AFTERNOON IS IN PROGRESS ACROSS THE LOWER MS VALLEY...DESPITE PLENTY OF FAIR WEATHER CUMULUS CLOUDS AROUND TO PARTIALLY BLOCK SUNSHINE. RATHER DEEP AND OCCASIONALLY STRONG SOUTHERLY FLOW EVIDENT TODAY WILL REMAIN PREDOMINANT OVER THE REGION IN ADVANCE OF A SHALLOW COLD FRONT EXPECTED TO COME INTO THE FORECAST AREA MONDAY. THEREFORE...ANOTHER QUITE MILD...BREEZY AND PARTIALLY SUNNY DAY IS ON TAP FOR SUNDAY. SUSTAINED WINDS AND GUSTS THIS AFTERNOON ARE DECIDEDLY BELOW WIND ADVISORY CRITERIA...AND GENERALLY REMAIN BELOW LOW END CRITERIA WORTHY OF HWO MENTION. PRESSURE GRADIENTS TOMORROW SHOULD BE SLIGHTLY MORE RELAXED AND THEREFORE AGAIN WELL SHY OF ADVISORY CRITERIA. HIGH TEMPERATURES TOMORROW WILL LIKELY TOP OUT SLIGHTLY WARMER THAN TODAY...RANKING AROUND 10 DEGREES ABOVE AVERAGE. THE AFOREMENTIONED COLD FRONT SLIDING IN FROM THE NORTHWEST ON MONDAY WILL MAKE FOR A TRICKY TEMPERATURE FORECAST SINCE THE AIRMASS AHEAD OF THE BOUNDARY WILL REMAIN EXTREMELY MILD. A MAJORITY OF THE SHOWERS ANTICIPATED IN ASSOCIATION WITH THE FRONT WILL BE ANAFRONTAL (BEHIND THE BOUNDARY) AND THUS LOCATIONS IN THE FAR NORTHWEST ARKLAMISS DELTA COULD BE IN STORE FOR COOL AND DAMP CONDITIONS WHILE MUCH OF CENTRAL AND SOUTHERN MS REMAINS VERY MILD WITH ONLY SLIGHT RAIN CHANCES. THIS FRONT SHOULD MAKE BETTER INROADS INTO THE REGION MONDAY NIGHT AND TUESDAY...BUT MAY NOT EVER CLEAR THROUGH SOUTHEASTERN MS BEFORE UPPER LEVEL MOTIVATION FOR PROGRESS WANES AND THE BOUNDARY STARTS BACKING UP AND WASHING OUT BY WEDNESDAY. IN RESPONSE TO LESSENING UPPER LEVEL FORCING THE SHOWERS ALONG AND BEHIND THE BOUNDARY WILL DWINDLE IN SIGNIFICANCE A GOOD DEAL AS TUESDAY EVOLVES. LATER NEXT WEEK FLOW WILL REMAIN RATHER ZONAL AND PROGRESSIVE WITH ARCTIC AIR REMAINING BOTTLED UP WELL TO THE NORTH. TEMPERATURES WILL RETURN TO BEING 5 TO 10 DEGREES ABOVE AVERAGE ALTHOUGH AT LEAST SLIGHT RAIN CHANCES WILL PERSIST IN NORTHERN ZONES THROUGH NEXT WEEKEND. THE BEST RAIN CHANCES FOR ALL AREAS (BUT ESPECIALLY NORTH OF I-20) WILL COME ON THURSDAY NIGHT INTO FRIDAY AS A MORE SOLID DISTURBANCE PASSES THROUGH OUR NEIGHBORHOOD IN THE MIDST OF THE MENTIONED ZONAL FLOW PATTERN. /BB/ && .AVIATION...BKN LOW CLOUDS COVER MOST OF THE AREA EXPECT FAR SE THIS MORNING...BUT CONDITIONS ARE GENERALLY VFR WITH CIGS GENERALLY RUNNING AROUND 5K FT. LOW CLOUDS ARE ASSOCIATED WITH A NARROW LAYER OF MOISTURE AND EXPECT THE CLOUDS TO CONTINUE TO MIX OUT SOMEWHAT THROUGH THE REST OF THE DAY. CONTINUED INFLUX OF GULF MOISTURE WILL RESULT IN REDEVELOPMENT OF WIDESPREAD STRATUS OVERNIGHT TONIGHT. SREF...LAMP AND HRRR INDICATE A TWO PRONGED INFLUX OF LOWER CIGS LATER TONIGHT...ONE IN THE DELTA AND THE OTHER INTO ERN MS AND AL. HAVE WENT WITH THIS SCENARIO IN 18Z TAFS SHOWING IFR CONDITIONS DEVELOPING AT KGLH AND THE 3 EASTERN TAF SITES. WITH S-SW LOW LEVEL FLOW CONTINUING SUN EXPECT GRADUAL IMPROVEMENT IN CIGS WITH MIXING THROUGH THE DAY. FLOW WILL NOT BE QUITE AS STRONG SUN AS TODAY SO DO NOT EXPECT AS GUSTY OF WINDS. /AEG/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 54 74 56 74 / 5 8 8 26 MERIDIAN 50 74 52 75 / 3 4 7 17 VICKSBURG 55 75 56 74 / 4 11 9 42 HATTIESBURG 53 76 55 76 / 4 6 4 10 NATCHEZ 56 74 58 74 / 4 10 7 32 GREENVILLE 57 74 57 62 / 7 12 18 59 GREENWOOD 57 72 57 67 / 4 12 16 50 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ BB/AEG
AREA FORECAST DISCUSSION...UPDATE
NWS JACKSON MS
1015 AM CST SAT NOV 29 2014 .UPDATE...STRENGTHENING LOW LEVEL SOUTHERLY FLOW AND RELATED GULF MOISTURE TRANSPORT IS RESPONSIBLE FOR THE MORNING CLOUDS AROUND PORTIONS OF THE REGION...BUT IS ALSO TO ACCOUNT FOR THE MORE PLEASANT TEMPERATURES. EXPECTING THESES CLOUDS TO GRADUALLY BREAK UP IN MOST CASES THROUGH EARLY AFTERNOON WITH TEMPERATURES TOPPING OUT THIS AFTERNOON SOME 5 TO 10 DEGREES ABOVE NORMAL. WINDS WILL BE GUSTY AT TIMES...ESPECIALLY IN THE ARKLAMISS DELTA THIS AFTERNOON WHERE GUSTS AFTER MIDDAY OVER 30 MPH WILL BE POSSIBLE. HIGHS FOR THIS AFTERNOON BOOSTED A LITTLE WITH RESPECT TO PREVIOUS EXPECTATIONS BUT OTHERWISE THE FORECAST FOR THE REMAINDER OF TODAY LEFT RELATIVELY UNCHANGED. /BB/ && .PREV DISCUSSION... /ISSUED 408 AM CST SAT NOV 29 2014/ SHORT TERM...TODAY THROUGH SUNDAY NIGHT...LATEST HRRR GUIDANCE AND MODEL SNDGS SHOW THAT MOISTURE TRANSPORT WILL BRING BACK GULF MOISTURE IN THE FORM OF STRATUS THIS MORNING. SOME STRATUS WAS NOTED ACROSS THE LOUISIANA DEVELOPING EAST-NORTHEAST. CONTINUED MOISTURE ADVECTION MAY LEAD TO RATHER PERSISTENT STRATO/CU IN FAR WESTERN AREAS THROUGH TODAY WHILE EASTERN AREAS SHOULD SEE PARTLY SUNNY SKIES. LOW CLOUDS WILL BE EVEN MORE WIDESPREAD TONIGHT AND MORE PERSISTENT ACROSS THE AREA INTO SUNDAY AND SUNDAY NIGHT. DEWPOINTS WILL GO FROM THE 30S AND 40S TO THE 50S FOR THE SHORT TERM. THE PRESSURE GRADIENT BETWEEN THE SURFACE HIGH TO THE EAST AND DEVELOPING LOW PRESSURE ACROSS CENTRAL PLAINS WILL BRING INCREASING SOUTH-SOUTHWEST FLOW THIS WEEKEND. 925 MB WINDS INCREASING TO 30-40 KT BY SAT AFTERNOON WILL LEAD TO BREEZY CONDITIONS. IT LOOKS LIKE THAT THERE WILL BE SOME DECENT SHEAR FROM THE UPPER TO LOWER LEVELS WHICH WILL REDUCING MIXING DOWN OF GUSTY WINDS TO THE SURFACE. LATEST GUIDANCE HAS WINDS BELOW WIND ADVISORY CRITERIA. SO DO NOT SEE ANY PARTICULAR NEED TO MENTION IN THE HWO. IN SPITE OF THESE CLOUDS...ADVECTION OF WARM/MOIST GULF AIR WILL ALLOW TEMPS TO WARM WELL INTO THE 60S TO AROUND 70 TODAY...AND UP TO 70 TO 74 MOST AREAS ON SUNDAY. LOWS TONIGHT WITH THE STRATUS AROUND WILL BE IN THE LOWER 50S EAST TO THE UPPER 50S WEST AS WELL AS MID TO UPPER 50S FOR SUNDAY NIGHT. TEMPERATURES WILL BE ABOVE NORMAL AT AROUND 5 TO 10 DEGREES FOR HIGHS AS WELL AS 10 TO 18 DEGREES ABOVE NORMAL FOR NIGHTLY LOWS. FOR EARLY SUNDAY MORNING THERE MAY BE SOME PATCHY ADVECTION FOG IN THE SOUTH FROM 09Z UNTIL 13Z. FOR SUNDAY AFTERNOON AND NIGHT A COLD FRONT WILL BE APPROACHING FROM THE NORTHWEST. THERE WILL BE JUST ENOUGH MOISTURE CONVERGENCE FOR SOME PATCHY LIGHT RAIN ACROSS THE NORTHWEST FOR SUNDAY AFTERNOON AND NIGHT. /17/ LONG TERM...MONDAY THROUGH SATURDAY...IT WONT FEEL LIKE THE FIRST WEEK OF DECEMBER FOR THE MOST PART AS WARMER THAN NORMAL CONDITIONS WILL PREVAIL THROUGH MUCH OF THE WEEK. THE WEEK WILL START AS A COLD FRONT NEARS THE REGION ON MONDAY. THIS WILL BRING CHANCES FOR SOME LIGHT RAIN TO THE ARKLAMISS AS IT SLOWLY PROGRESSES THROUGH THE REGION. A 1044MB SFC HIGH WILL BE TRYING TO PUSH DOWN IN BEHIND IT. THIS WILL HELP BRING IN SOME COLDER LOW LEVEL AIR TO THE REGION BEHIND THE FRONT FOR LATE MONDAY THROUGH TUESDAY. HOWEVER...THE CENTER OF THE HIGH WILL ACTUALLY SKIRT OFF TO THE EAST AND WE WONT SEE A DRASTIC COOLDOWN LIKE WE HAVE IN PREVIOUS WEEKS BUT TUESDAY WILL BE THE COLDEST DAY OF THE WEEK. TEMPERATURES WILL MODERATE RATHER QUICKLY WEDNESDAY THROUGH THE REST OF THE WEEK INTO THE WEEKEND AND IT WILL FEEL A BIT MORE LIKE SPRING THAN THE BEGINNING OF DECEMBER. THE PATTERN OVER THE MID-SOUTH WILL ALSO REMAIN FAIRLY ZONAL AND DISTURBANCES WILL MOVE THROUGH THIS FLOW ACROSS OUR NORTH. IT LOOKS LIKE MOST OF THEM SHOULD REMAIN NORTH OF THE CWA AND KEEP US DRY THROUGH THE WEEK. BY THE END OF THE WEEK ANOTHER FRONT LOOKS TO STALL JUST NORTH OF THE CWA AND COULD BRING OUR NEXT CHANCE OF RAIN AROUND THURSDAY OR FRIDAY. THE GFS DOESNT BRING IT THROUGH AND KEEPS THE SOUTH DRY AND UNDER A RIDGING INFLUENCE. THE ECMWF BRINGS IT FURTHER SOUTH INTO THE CWA. REGARDLESS THIS SHOULD BRING SOME RAIN TO AT LEAST A PORTION OF THE CWA. /28/ && .AVIATION...N LOW CLOUDS COVER MOST OF THE AREA EXPECT FAR SE THIS MORNING. ONLY MVFR CIGS HOWEVER ARE IN THE FAR NW DELTA INCLUDING KGLH WITH REST OF AREA RUNNING IN THE 4500-5500 FOOT RANGE. WITH STRONG LOW LEVEL WINDS ACROSS AREA EXPECT CLOUDS TO GRADUALLY MIX OUT SOMEWHAT AND CIGS TO LIFT...THOUGH KGLH MAY REMAIN MVFR INTO AT LEAST EARLY AFTERNOON. EXPECT LOW CLOUDS TO BECOME WIDESPREAD AGAIN TONIGHT...WITH MVFR CIGS LIKELY TO EXPAND TO ENCOMPASS MOST IF NOT ALL OF THE AREA. GRADUAL IMPROVEMENT WILL THEN OCCUR AGAIN SUNDAY WITH DAYTIME MIXING. WINDS THE OTHER MAIN CONCERN AS S-SW WINDS GENERALLY IN THE 30-40 KNOT RANGE JUST ABOVE THE SURFACE WILL MIX DOWN TO PRODUCE OCNL 20-30 KT GUSTS DURING THE DAYLIGHT HOURS... ESPECIALLY OVER DELTA WHERE WINDS WILL STRONGEST. /AEG/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 70 55 72 57 / 5 7 9 11 MERIDIAN 69 52 72 54 / 3 7 8 10 VICKSBURG 72 56 73 57 / 7 8 10 12 HATTIESBURG 71 54 73 57 / 3 7 7 10 NATCHEZ 71 58 73 58 / 5 9 10 11 GREENVILLE 71 57 71 57 / 9 12 14 18 GREENWOOD 69 56 71 57 / 8 11 10 17 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ BB/AEG/17/28
AREA FORECAST DISCUSSION
NWS JACKSON MS
408 AM CST SAT NOV 29 2014 .SHORT TERM...TODAY THROUGH SUNDAY NIGHT...LATEST HRRR GUIDANCE AND MODEL SNDGS SHOW THAT MOISTURE TRANSPORT WILL BRING BACK GULF MOISTURE IN THE FORM OF STRATUS THIS MORNING. SOME STRATUS WAS NOTED ACROSS THE LOUISIANA DEVELOPING EAST-NORTHEAST. CONTINUED MOISTURE ADVECTION MAY LEAD TO RATHER PERSISTENT STRATO/CU IN FAR WESTERN AREAS THROUGH TODAY WHILE EASTERN AREAS SHOULD SEE PARTLY SUNNY SKIES. LOW CLOUDS WILL BE EVEN MORE WIDESPREAD TONIGHT AND MORE PERSISTENT ACROSS THE AREA INTO SUNDAY AND SUNDAY NIGHT. DEWPOINTS WILL GO FROM THE 30S AND 40S TO THE 50S FOR THE SHORT TERM. THE PRESSURE GRADIENT BETWEEN THE SURFACE HIGH TO THE EAST AND DEVELOPING LOW PRESSURE ACROSS CENTRAL PLAINS WILL BRING INCREASING SOUTH-SOUTHWEST FLOW THIS WEEKEND. 925 MB WINDS INCREASING TO 30-40 KT BY SAT AFTERNOON WILL LEAD TO BREEZY CONDITIONS. IT LOOKS LIKE THAT THERE WILL BE SOME DECENT SHEAR FROM THE UPPER TO LOWER LEVELS WHICH WILL REDUCING MIXING DOWN OF GUSTY WINDS TO THE SURFACE. LATEST GUIDANCE HAS WINDS BELOW WIND ADVISORY CRITERIA. SO DO NOT SEE ANY PARTICULAR NEED TO MENTION IN THE HWO. IN SPITE OF THESE CLOUDS...ADVECTION OF WARM/MOIST GULF AIR WILL ALLOW TEMPS TO WARM WELL INTO THE 60S TO AROUND 70 TODAY...AND UP TO 70 TO 74 MOST AREAS ON SUNDAY. LOWS TONIGHT WITH THE STRATUS AROUND WILL BE IN THE LOWER 50S EAST TO THE UPPER 50S WEST AS WELL AS MID TO UPPER 50S FOR SUNDAY NIGHT. TEMPERATURES WILL BE ABOVE NORMAL AT AROUND 5 TO 10 DEGREES FOR HIGHS AS WELL AS 10 TO 18 DEGREES ABOVE NORMAL FOR NIGHTLY LOWS. FOR EARLY SUNDAY MORNING THERE MAY BE SOME PATCHY ADVECTION FOG IN THE SOUTH FROM 09Z UNTIL 13Z. FOR SUNDAY AFTERNOON AND NIGHT A COLD FRONT WILL BE APPROACHING FROM THE NORTHWEST. THERE WILL BE JUST ENOUGH MOISTURE CONVERGENCE FOR SOME PATCHY LIGHT RAIN ACROSS THE NORTHWEST FOR SUNDAY AFTERNOON AND NIGHT. /17/ .LONG TERM...MONDAY THROUGH SATURDAY...IT WONT FEEL LIKE THE FIRST WEEK OF DECEMBER FOR THE MOST PART AS WARMER THAN NORMAL CONDITIONS WILL PREVAIL THROUGH MUCH OF THE WEEK. THE WEEK WILL START AS A COLD FRONT NEARS THE REGION ON MONDAY. THIS WILL BRING CHANCES FOR SOME LIGHT RAIN TO THE ARKLAMISS AS IT SLOWLY PROGRESSES THROUGH THE REGION. A 1044MB SFC HIGH WILL BE TRYING TO PUSH DOWN IN BEHIND IT. THIS WILL HELP BRING IN SOME COLDER LOW LEVEL AIR TO THE REGION BEHIND THE FRONT FOR LATE MONDAY THROUGH TUESDAY. HOWEVER...THE CENTER OF THE HIGH WILL ACTUALLY SKIRT OFF TO THE EAST AND WE WONT SEE A DRASTIC COOLDOWN LIKE WE HAVE IN PREVIOUS WEEKS BUT TUESDAY WILL BE THE COLDEST DAY OF THE WEEK. TEMPERATURES WILL MODERATE RATHER QUICKLY WEDNESDAY THROUGH THE REST OF THE WEEK INTO THE WEEKEND AND IT WILL FEEL A BIT MORE LIKE SPRING THAN THE BEGINNING OF DECEMBER. THE PATTERN OVER THE MID-SOUTH WILL ALSO REMAIN FAIRLY ZONAL AND DISTURBANCES WILL MOVE THROUGH THIS FLOW ACROSS OUR NORTH. IT LOOKS LIKE MOST OF THEM SHOULD REMAIN NORTH OF THE CWA AND KEEP US DRY THROUGH THE WEEK. BY THE END OF THE WEEK ANOTHER FRONT LOOKS TO STALL JUST NORTH OF THE CWA AND COULD BRING OUR NEXT CHANCE OF RAIN AROUND THURSDAY OR FRIDAY. THE GFS DOESNT BRING IT THROUGH AND KEEPS THE SOUTH DRY AND UNDER A RIDGING INFLUENCE. THE ECMWF BRINGS IT FURTHER SOUTH INTO THE CWA. REGARDLESS THIS SHOULD BRING SOME RAIN TO AT LEAST A PORTION OF THE CWA. /28/ && .AVIATION...MVFR-IFR CEILINGS WERE DEVELOP EASTWARD FROM LOUISIANA AND ARKANSAS EARLY THIS MORNING. THIS WILL SPREAD EAST TO MAINLY MVFR CEILINGS AROUND OR JUST BEFORE DAYBREAK AT GLH/GWO/JAN/HKS. AT PIB/HBG THE POTENTIAL FOR SUB-VFR IS NOT AS HIGH ALTHOUGH BRIEF IFR IS A POSSIBILITY. FLIGHT CATS SHOULD IMPROVE TO VFR IN ALL AREAS BY MIDDAY TODAY AT THE LATEST WITH WINDS OCCASIONALLY GUSTY FROM THE SOUTH...ESPECIALLY IN THE ARKLAMISS DELTA./17/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 67 55 72 57 / 5 7 9 11 MERIDIAN 67 52 72 54 / 3 7 8 10 VICKSBURG 70 56 73 57 / 7 8 10 12 HATTIESBURG 70 54 73 57 / 3 7 7 10 NATCHEZ 70 58 73 58 / 5 9 10 11 GREENVILLE 68 57 71 57 / 9 12 14 18 GREENWOOD 66 56 71 57 / 8 11 10 17 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ 28/17
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
947 PM CST Sun Nov 30 2014 .UPDATE: Issued at 934 PM CST Sun Nov 30 2014 At this point I haven`t seen much in the latest observational and model data to suggest significant changes are need to the previous forecast. The cold front has passed through the CWA, stretching across far southern IL and southeast MO at 03z. Very spotty and very weak fast moving echoes have begun to show up on regional radars within the cold air across southern MO and southern IL, but currently south of the freezing line. These appear to be in response to isentropic lift over the shallow cold dome. The last few runs of the RAP and HRRR suggest this may be the pattern the remainder of the night and into Monday morning with these spotty small fast-moving blips of precipitation, which will eventually be occuring in the sub-freezing air as it continues to spread southward. The current chance pops appear to have this adequately covered and the only real change was to bump slightly northward the northern periphery of slight chance pops. The two inch ground temperature here at the WFO in Weldon Spring is 46 degrees, which would suggest any ice issues with this spotty ZR would be on elevated surfaces. Unless something changes, the coverage of precipitation and associated impacts would be less than needed for an advisory. We will continue to monitor closely through the overnight hours should coverage become greater than currently anticipated and then changes would be required. Glass && .SHORT TERM: (Through Monday) Issued at 229 PM CST Sun Nov 30 2014 Main focus remains precip chances thru the period. Mdls remain in fairly good agreement in most aspects. Still believe the nrn extent of mdl QPF is overdone due to issues mentioned yesterday. Mdls prog the weak s/w currently over ern TX/OK region to move newd this evening. This s/w shud arrive over the srn MO/IL and KY region about the same time as the 850mb cdfnt. This combination of low and upper level forcing shud be enuf for precip to develop. This precip shud develop around 06z tonight and persist thru much of the night. The main question is exactly where will the precip develop. Latest mdl guidance continues to suggest this will develop just SE of the CWA. However, given the uncertainty with location, will keep high chance PoPs across the far srn tier of counties. Precip type continues to be a struggle. Precip shud begin as RA and freeze as the cold air pushes swd thru the region. MO mesonet obs continue to show 4 inch soil temps in the lower 50 F range across SE MO. This shud limit ice accumulation to elevated sfcs if any does occur. That said, these elevated sfcs may also include bridges and overpasses if untreated. One chance from mdl soundings yesterday is precip may linger a bit later than prev anticipated. Latest mdl soundings suggest that if precip continues as far N as KFAM Mon morning, IP is possible. Have added mention of IP for Mon morning along the nrn edges of the precip shield, but kept PoPs low for this time. Mdls have come into better agreement regarding temps and trended twd more of a compromise for temps thru the period. Given the warm sfc temps and uncertainty where precip will develop late tonight into Mon, will hold off on issuing a headline for now. However, a headline will likely be needed if precip develops further N than currently anticipated. Tilly .LONG TERM: (Tuesday through Next Sunday) Issued at 315 PM CST Sun Nov 30 2014 Once the precip moves out of the region on Mon, the sfc ridge will quickly move thru the region and be S of the CWA by mid day Tues. With clouds clearing out, ample insolation shud allow temps to climb into the 40s. Mdls remain in fairly good agreement thru Thurs. Beyond Thurs, mdl solns diverge. The ECMWF/GEM are in better agreement regarding mass fields with a more amplified pattern late this week compared to the GFS. Have therefore trended twd a ECMWF/GEM compromise. However, have kept low PoPs lingering across much of the CWA due to the GFS soln. One change made from the prev few shifts is a switch from a RA or SN forecast to a RA or FZRA forecast. Latest GFS soundings do not support SN thru the extd portion of the forecast. Due to inconsistencies from one run to the next and differences among mdls thru the extd periods, have low confidence in any one mdl soln. However, mdls do come into better agreement for Sun and into next week as a trof ejects into the Plains. Have trended PoPs slightly higher late in the period with better mdl agreement. Tilly && .AVIATION: (For the 00z TAFs through 00z Monday Evening) Issued at 546 PM CST Sun Nov 30 2014 Cold front has exited the forecast area. So dealing with mvfr sc behind the boundary this evening. SC has moved south of KUIN and should scatter out at KCOU by 04z Monday and in metro area by 08z Monday. Otherwise, just some high clouds streaming northeast through region this evening. As for winds, to persist from the north and remain gusty through most of forecast period until Monday afternoon as surface ridge settles in and gradient weakens. Moisture is limited so no precipitation expected at taf sites. Specifics for KSTL: Cold front has exited the forecast area. So dealing with mvfr sc behind the boundary this evening. SC to scatter out over metro area by 08z Monday. Otherwise, just some high clouds streaming northeast through region this evening. As for winds, to persist from the north and remain gusty through most of forecast period until 22z Monday as surface ridge settles in and gradient weakens. Moisture is limited so no precipitation expected at taf site. Byrd && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
300 AM CST Sat Nov 29 2014 .DISCUSSION... Issued at 300 AM CST SAT NOV 29 2014 Above normal temperatures are expected to continue today, as a midlevel ridge axis shifts over the forecast area and 925 hPa temperatures increase to around +16 C throughout the CWA. Highs today should reach the 60s in most locations, and slightly lighter winds will also help temperatures feel warmer this afternoon. The main focus in the short term will be the arrival of a strong cold front on Sunday. The front has already begun plunging southeast across Montana, and will arrive in our area on Sunday. Timing of the frontal passage is just a touch slower than yesterday, which creates a slightly higher potential of light rain showers in southeastern portions of the CWA along/ahead of the front Sunday afternoon. Upper 40s to lower 50s dewpoints are expected to surge into the area ahead of the front, and may combine with lift along the cold front to support light precipitation in central MO where moisture is highest. NAM and some SREF soundings indicate a lingering saturated layer around ~900 hPa just behind the front which could support a brief window of freezing drizzle or perhaps some very light sleet as a result of quickly falling boundary layer temperatures, but have some concerns that the saturated layer may be a bit overdone and may be too shallow to support precipitation just behind the front, so have not included any wintry precipitation in the forecast at this time. Should more of the soundings become supportive, the most likely locations for freezing drizzle transitioning to light sleet would be in northwest MO on Sunday morning, and then in central MO late Sunday afternoon or evening. Sharply colder temperatures and brisk northwest winds are expected immediately following frontal passage, allowing temperatures to tank into the teens by daybreak Monday. A little recovery in temperatures is possible Monday afternoon as clouds clear out, but highs are not expected to surpass the freezing mark in the CWA. However, the cold front`s parent trough will continue to sweep off to the east, and will allow temperatures to moderate back into the 40s or low 50s for Tuesday through the rest of the forecast period. The next chance of precipitation is still expected Wednesday night and Thursday as a shortwave trough drifts eastward across the region. Soundings look mainly supportive of liquid precipitation, but have included a chance of rain or snow to account for some uncertainty in temperature profiles. In any case, the zonal flow aloft and seasonable daytime temperatures should not support any snow accumulations during this period. && .AVIATION...(For the 06Z TAFS through 06Z Saturday Night) Issued at 1140 PM CST FRI NOV 28 2014 Feeling is that fog development will not be prevailing through the entire early morning period, as dry air above the surface and mixed out boundary layer should provide enough mitigating ingredients to prevent the widespread, prevailing fog. That being said, moisture will make its way into the area and temperature/dew point depression will be rather low, so will go with a mention of MVFR fog, with perhaps some brief IFR periods. HRRR guidance through the night indicates some patchy IFR VIS near the terminals, so will hold on to the mention of IFR. Otherwise VFR conditions prevail. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ DISCUSSION...Laflin AVIATION...Leighton
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1146 PM CST Fri Nov 28 2014 .DISCUSSION... Issued at 304 PM CST FRI NOV 28 2014 Unseasonably warm weather will continue through Saturday and for parts of the area into Sunday. But by Sunday afternoon, the bottom will fall out as a strong cold front blasts through the area. As has been the case the last few days, models remain consistent in moving the front through the day, but there remains some timing differences that then result in the potential for huge bust potential. The GFS remains the fastest and seems like an outlier at this point given the closer clustering of timing amongst the GEM, NAM and the ECMWF. With that in mind, temperatures in the far southeastern portions of the forecast area may climb into the lower 60s. A few hundred miles to the northwest, far northwestern Missouri will likely see their highs set before sunrise, with temperatures steady or falling throughout the day. The forecast depicts a 30 degree temperature spread for highs on Sunday and it`s quite possible this could be closer to 40 degrees given the magnitude of the cold air behind the front and the air mass it`s replacing. The other aspect of this frontal passage will be the potential for showers or drizzle ahead of the front and drizzle or freezing drizzle behind the front. Forecast soundings show a very moist low-level environment with a small amount of positive buoyancy ahead of the front. This may result in a few showers in our far southeastern zones. Then, in the afternoon, the front plows through, knocking temperatures back below freezing with winds picking up from the northwest. This could have several effects. First, the low-levels remain saturated as they fall below freezing, and with no ice crystals could result in a brief window of freezing drizzle. Another possible scenario is that if there is some prefrontal precipitation that mainly elevated surfaces could become slick as temperatures and winds quickly cool those surfaces down. Models are in better agreement for the first half of the week with cold high pressure being the main player. But the inconsistencies that have been present the last few days remain mostly the same for the later half of the week. The GFS remains the most progressive with zonal flow allowing an eastern Pacific trough to quickly move ashore and move eastward into the center of the country. The GEM and the ECMWF, while showing a similar pattern, maintain a stronger ridge over the western CONUS and are slower to track that upper trough to the east. The result of this continues to be that the ECMWF and GEM are colder at the surface with high pressure through the Upper Midwest into the Lower Missouri Valley. In contrast, with the GFS being more progressive, it develops lee troughing and allows warmer air and precipitation to advect northward. Confidence remains low from about Wednesday onward given the differences in the models. && .AVIATION...(For the 06Z TAFS through 06Z Saturday Night) Issued at 1140 PM CST FRI NOV 28 2014 Feeling is that fog development will not be prevailing through the entire early morning period, as dry air above the surface and mixed out boundary layer should provide enough mitigating ingredients to prevent the widespread, prevailing fog. That being said, moisture will make its way into the area and temperature/dew point depression will be rather low, so will go with a mention of MVFR fog, with perhaps some brief IFR periods. HRRR guidance through the night indicates some patchy IFR VIS near the terminals, so will hold on to the mention of IFR. Otherwise VFR conditions prevail. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ DISCUSSION...CDB AVIATION...Leighton
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
909 AM MST SAT NOV 29 2014 .UPDATE... STRONG SHORTWAVE SEEN IN WATER VAPOR IMAGERY ROTATING INTO THE PACIFIC NW THIS MORNING. THIS WAVE WILL ROTATE THROUGH THE AREA TONIGHT. COUPLED JET REMAINS OVER AREA PER UPPER AIR OBSERVATIONS PROVIDING LIFT. THIS WILL ALSO PROVIDE LIFT INTO TONIGHT. INTENSE FRONTOGENESIS SNOW BAND WAS OVER N MT THIS MORNING PER RADAR/OBSERVED CONDITIONS. HRRR SHOWS 700 MB FRONTOGENESIS BAND STRENGTHENING AS IT MOVES S INTO THE AREA THIS AFTERNOON. BY 00Z TONIGHT THE STRONGEST PORTION OF THE BAND IS OVER SOUTHERN ROSEBUD TO FALLON COUNTY. SO...GIVEN ALL OF THE ABOVE...WILL INCREASE SNOW AMOUNTS ALONG THE BAND. INCREASE WILL PUT JUDITH GAP AND WHEATLAND COUNTY IN A WINTER STORM WARNING...NO CHANGES TO OTHER SNOW HIGHLIGHTS. FRONT MADE IT THROUGH KSHR AT 1414Z AND THRU KLVM AT 15Z PUTTING AN END TO THE GAP FLOW WINDS. FRONT IS ALSO THROUGH FISHTAIL. HAVE CANCELLED WIND ADVISORIES FOR KLVM AND NYE. MODELS HAVE BEEN DOING A POOR JOB IN KEEPING UP WITH THE WIND AND TEMPERATURE CHANGES ALONG THE FRONT. HAVE GONE WITH CURRENT TEMPERATURES TO REPRESENT TODAY/S HIGHS AND STILL EXPECT FALLING TEMPERATURES THROUGH THE DAY. ARTHUR && .SHORT TERM...VALID FOR TDY AND SUN... A REMARKABLE CHANGE IN AIRMASSES IS ONGOING. AT 3AM...TEMPS REMAIN IN THE 50S WITH STRONG DOWNSLOPE WINDS AT LIVINGSTON AND SHERIDAN...BUT ITS FALLEN TO 1 ABOVE WITH GUSTY NORTH WINDS AT JUDITH GAP. COLD FRONT HAS PUSHED THROUGH HARLOWTON...LAUREL AND CROW AGENCY AND IS MOVING TO THE SOUTH AND WEST. A LARGE AREA OF STRATUS/FOG IS ALSO SURGING IN WITH THE SHALLOW COLD AIR. THERE ARE SOME LIGHT SNOW SHOWERS OR FLURRIES IN OUR NW PARTS BUT FOR THE MOST PART PCPN HAS NOT ARRIVED YET. WILL NOT MAKE ANY CHANGES TO THE WIND HIGHLIGHTS IN EFFECT AT THIS TIME BUT WILL BE ABLE TO CANCEL THEM SOON WITH THE ARCTIC FRONT BEARING DOWN. SW WINDS HAVE IMPRESSIVELY GUSTED OVER 50 MPH FOR THE PAST SEVERAL HOURS AT SHERIDAN...WITH A PEAK OF 66 MPH IN THE LATE EVENING. WINDS AT LIVINGSTON ARE ALSO GUSTING INTO THE 50S. SNOW WILL DEVELOP TODAY AS ASCENT INCREASES WITH APPROACHING PAC NW TROF. COOLING CLOUD TOPS NOTED FROM NORTHEAST OR TO WESTERN MT ASSOCIATED WITH MID LEVEL BAROCLINIC ZONE. FRONTOGENESIS WILL SPREAD INTO OUR CWA AS WE MOVE INTO DAYTIME HOURS AND WE WILL SEE SNOW INCREASE INITIALLY IN OUR NW THEN SPREAD TOWARD THE EAST AND SOUTH OVER TIME. BILLINGS SHOULD SEE LIGHT SNOW OR FLURRIES DEVELOP THIS MORNING THEN ACCUMULATING SNOWFALL BY AFTERNOON. SNOWFALL WILL REACH ITS MAXIMUM LATE THIS AFTERNOON AND EVENING THEN TAPER OFF LATE TONIGHT INTO EARLY SUNDAY MORNING AS UPPER TROF SLIDES EAST. IT SHOULD BE NOTED THAT MODELS CONTINUE TO HAVE A VERY POOR HANDLING OF SFC COLD FRONT...BUT PCPN ITSELF WILL BE TIED TO THE MID AND UPPER LEVEL FEATURES. DESPITE THE SEVERE LOW LEVEL COOLING THERE WILL BE A FAIRLY DEEP WARMER LAYER THAT WILL AID IN SNOW GROWTH AS THE ASCENT INCREASES TODAY...WITH SNOW RATIOS CERTAIN TO DECREASE LATE TONIGHT AS THE ENTIRE LAYER EVENTUALLY TURNS MUCH COLDER AND WE LOSE THE DENDRITIC LAYER. OVERALL A GENERAL 2 TO 4 INCH SNOWFALL SEEMS IN STORE...HIGHEST IN OUR WEST AND ALONG OUR SOUTHERN FOOTHILLS...WITH FEW INCHES MORE OVER THE MTNS. IMPACTS WILL BE TIED TO THIS MODEST SNOWFALL COMBINED WITH SOME NORTH WINDS...BLOWING SNOW...POOR VISIBILITY AND WIND CHILLS FALLING BELOW ZERO. DO NOT UNDERESTIMATE THE HARSHNESS OF THIS AIRMASS. IT IS ALREADY 8 BELOW ZERO AT CUT BANK AND MUCH COLDER THAN THAT IN CORE OF SFC HIGH IN NORTHERN ALBERTA. WE SHOULD HAVE NO TROUBLE FALLING BELOW ZERO ACROSS OUR CWA BY THIS EVENING WITHOUT THE HELP OF RADIATIONAL COOLING. AFTER A CHILLY DAY SUNDAY WITH HIGHS IN THE SINGLE DIGITS TO LOWER TEENS...WE WILL SEE CLEARING AND ANOTHER COLD NIGHT SUNDAY NIGHT BEFORE LEE SIDE TROFFING/WARM ADVECTION COMMENCES. HAVE DROPPED EXPECTED TEMPS OVER THE NEXT 2 DAYS DOWN SLIGHTLY. JKL .LONG TERM...VALID FOR MON...TUE...WED...THU...FRI... PRETTY GOOD AGREEMENT BETWEEN THE GFS AND ECMWF FOR THE PERIOD OF MONDAY THROUGH WEDNESDAY. MODELS DIVERGE A BIT FROM THURSDAY ONWARD BUT NOT TO A LARGE DEGREE. OVERALL...THE MOST ACTIVE PERIOD OF WEATHER LOOKS TO BE MONDAY NIGHT INTO TUESDAY. AFTER A BRIEF PERIOD OF ZONAL FLOW ON MONDAY...WHICH WILL ALLOW THE ARCTIC AIRMASS TO PUSH EAST...AN UPPER TROUGH WILL SWEEP ACROSS MONTANA MONDAY NIGHT AND TUESDAY. THIS WILL TURN THE FLOW CYCLONIC AND PUSH A BIT OF A REINFORCING COLD FRONTAL BOUNDARY THROUGH THE AREA. THIS COLD FRONT WILL NOT BE NEARLY AS COLD AS THE ONE THIS WEEKEND...BUT WILL ACT AS AN OVER RUNNING FOCUS FOR PRECIPITATION. THE GFS HAS BEEN CONSISTENTLY HITTING THE AREA WITH QPF FOR THIS OVER RUNNING FEATURE AND NOW THE ECMWF HAS JUMPED ON BOARD. RAISED POPS FOR THIS AND MAY NEED TO JUMP UP TO LIKELY ON FUTURE SHIFTS. THERMAL PROFILE DOES NOT LOOK TREMENDOUSLY COLD...SO NOT EXPECTING MUCH MORE THAN A TRACE TO TWO INCHES OF SNOW WITH THIS. WEAK ZONAL FLOW TAKES OVER FOR TUESDAY NIGHT ONWARD. THIS WILL ALLOW FOR A STEADY WARM UP THROUGH THE END OF THE WEEK. A WEAK MOISTURE PUSH WILL ALLOW FOR LOW POPS IN THE MOUNTAINS. TWH && .AVIATION... A COLD FRONT HAS BROUGHT LOW STRATUS TO THE ENTIRE AREA THIS MORNING AND WILL PERSIST THROUGH TONIGHT. CEILINGS WILL BE VERY LOW WITH LIFR TO VLIFR CONDITIONS EXPECTED. SNOW WILL DEVELOP LATE THIS MORNING AND CONTINUE INTO THE EVENING. THE SNOW WILL LOWER VISIBILITIES TO AROUND A MILE AT TIMES...WITH A 1/4 MILE POSSIBLE IN HEAVIER SNOW BANDS. THE HEAVIEST SNOWFALL WILL BE FROM LIVINGSTON TO BILLINGS THIS AFTERNOON THROUGH TONIGHT. MOUNTAINS WILL BE OBSCURED. RICHMOND && .PRELIMINARY POINT TEMP/POPS... TDY SUN MON TUE WED THU FRI ------------------------------------------------------- BIL 013 905/011 002/033 023/036 018/036 023/044 027/044 +/S +0/B 01/B 25/J 11/B 21/B 11/B LVM 032 905/015 004/033 026/037 021/039 027/043 028/043 +/S +0/B 01/B 25/J 12/J 22/W 11/B HDN 015 904/012 902/033 020/036 014/037 018/043 022/044 9/S +1/B 01/B 25/J 11/B 21/B 11/B MLS 015 906/010 904/030 017/028 009/031 014/037 020/040 9/S 80/B 00/U 24/J 11/B 11/B 10/B 4BQ 021 903/010 904/034 020/035 013/037 019/041 021/043 6/S 91/B 01/U 14/J 12/J 21/B 01/B BHK 019 905/006 905/028 016/027 008/029 013/035 019/039 7/S 71/B 00/U 13/J 11/U 11/B 10/B SHR 030 902/011 904/036 024/039 017/038 021/044 023/045 6/S +2/S 00/B 23/W 12/J 21/B 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...WINTER STORM WARNING IN EFFECT UNTIL 11 AM MST SUNDAY FOR ZONES 28-63. WINTER WEATHER ADVISORY IN EFFECT UNTIL 11 AM MST SUNDAY FOR ZONES 29>42-56>58-64>66. WY...WINTER WEATHER ADVISORY IN EFFECT UNTIL 11 AM MST SUNDAY FOR ZONE 99. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1142 AM CST SAT NOV 29 2014 .UPDATE... ISSUED AT 1142 AM CST SAT NOV 29 2014 HASTINGS HAS BROKEN THE RECORD HIGH BEFORE NOON! PLEASE SEE THE RECORE EVENT REPORT /RER/ FOR THE DETAILS. 76F HERE AT THE OFFICE AT 1132 AM. WE ARE STILL SEEING THE VERY ODD TEMP ANOMALIES AS THE NIGHT SHIFT POINTED OUT OVERNIGHT. SOME LOCATIONS ARE MUCH COOLER THAN WOULD BE EXPECTED. THIS IS WREAKING HAVOC WITH HOURLY TEMP CURVES. CURRENT TEMPS WERE MERGED WITH FCST HIGHS (WHICH WERE RAISED MOST LOCATIONS) IN AN ATTEMPT TO GET FCST TEMP CURVES BACK ON TRACK WITH REALITY. UPDATE ISSUED AT 925 AM CST SAT NOV 29 2014 WE HAVE EVALUATED THE NEED FOR A RED FLAG WARNING N AND W OF THE TRI-CITIES FOR THIS AFTN. AM CONCERNED THAT THE NAM/GFS ARE UNDER-FORECASTING WINDS BASED ON THEIR UNREALISTICALLY LOW FCST MIXING HEIGHTS. THE RAP FCST SOUNDINGS SHOW WHAT WE THINK WILL HAPPEN WITH A TYPICAL UNSTABLE BL DEVELOPING. THAT MEANS WINDS WILL BE HIGHER THAN CURRENTLY FCST. THAT IS A PROBLEM BECAUSE POOR MODELING LOWERS CONFIDENCE. THERE IS A CHANCE WE MAY NEED TO ISSUE A SHORT LEAD-TIME RFW FOR VALLEY/SHERMAN COUNTIES AND POSSIBLY BUFFALO AND DAWSON. THE ONE MITIGATING FACTOR IS HIGH CLOUDS. THAT WILL INHIBIT MIXING. IT ALSO SOMEWHAT ENCOURAGING THAT THE ISOBARS ARE FAIRLY SPREAD APART OVER THE CNTRL PLAINS...IE A WEAK PRES GRAD. WE DID NOTE LBF EXPANDED THEIR RFD UP TO OUR NW/N BORDER. WE WILL CLOSELY MONITOR. THE FCST WILL BE UPDATED TO INCREASE WINDS SOME AND THE FIRE WX FCST WILL ALSO BE UPDATED TO INCREASE MIXING HGTS. UPDATE ISSUED AT 727 AM CST SAT NOV 29 2014 SENT AN ENHANCED SHORT-TERM FCST /ESTF/ UPDATE TO INCREASE SKY COVER TO P/CLOUDY. HOURLY FCST DWPTS WERE ALSO RUNNING TOO HIGH COMPARED TO REALITY. UPDATED FCST WILL POST SHORTLY WITH THESE ADJUSTMENTS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 423 AM CST SAT NOV 29 2014 PLENTY OF HIGH LEVEL CLOUD COVER IS SPILLING ACROSS THE CENTRAL PLAINS THIS MORNING...ASSOCIATED WITH AN UPPER LEVEL JET STREAK PUSHING ACROSS THE ROCKY MOUNTAINS. EXPECT THIS CLOUD COVER TO LINGER THROUGHOUT THE AFTERNOON...POTENTIALLY HOLDING DOWN HIGH TEMPERATURES A COUPLE OF DEGREES...BUT OTHERWISE HAVING LITTLE IMPACT. WITH LOW LEVEL WESTERLY FLOW CONTINUING ALONG WITH A VERY MILD AIRMASS IN PLACE...EXPECT THE POTENTIAL FOR ANOTHER EXTREMELY NICE FALL AFTERNOON ACROSS THE REGION...WITH RECORD HIGH TEMPERATURES CURRENTLY FORECAST FOR BOTH GRAND ISLAND AND HASTINGS. WHILE A BEAUTIFUL AFTERNOON IS IN STORE FOR THE REGION...CONDITIONS WILL CHANGE ABRUPTLY OVERNIGHT...AS A VERY STRONG COLD FRONT DROPS SOUTHWARD ACROSS THE PLAINS. MODEL DATA CONTINUES TO INDICATE OVER A 20C+ DROP IN TEMPS AT 850 BEHIND THIS FRONT...WITH THE LEADING EDGE OF THE COLD AIRMASS FORECAST TO REACH GRAND ISLAND AROUND MIDNIGHT. WITH THE VERY DENSE AND COLD NATURE OF THIS AIRMASS...WOULD NOT BE SURPRISED IF IT WILL BE ABLE TO RACE INTO NORTH CENTRAL KANSAS PRIOR TO DAWN SUNDAY MORNING...AND ADJUSTED LOW TEMPERATURES DOWN A COUPLE OF DEGREES TO COMPENSATE FOR THIS DESPITE THE STRONG NORTHERLY WINDS THAT ARE ANTICIPATED TO ACCOMPANY THIS FRONT. WHILE THERE IS ONLY VERY SHALLOW MOISTURE DEPICTED IN THE MODEL DATA...AND THE CLASSIC DRIZZLE SIGNATURE IS NOT EVIDENT IN PRECIP FIELDS...DID GO AHEAD AND ADD SOME PATCHY FREEZING DRIZZLE TO NORTHEASTERN PORTIONS OF THE FORECAST AREA DURING THE PRE-DAWN HOURS SUNDAY MORNING...AS THE NAM INDICATES A BIT OF LIFT IN THIS LOWEST LAYER...WHICH MAY BE JUST ENOUGH TO SQUEEZE OUT A FEW SMALL DROPS OF MOISTURE. THAT SAID...LITTLE ICE ACCUMULATION IS ANTICIPATED...AND DID NOT INSERT ANY QPF INTO THE FORECAST IN THE FORM OF EITHER LIQUID OR ICE FOR THE TIME BEING. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 423 AM CST SAT NOV 29 2014 TEMPERATURE WISE...AFTER BASKING IN NEAR-RECORD TO RECORD WARMTH FRIDAY AND TODAY...BY FAR THE BIGGEST STORY OF THIS 6-DAY PERIOD ARRIVES RIGHT AWAY IN THE FORM OF A MAJOR CHILL-DOWN FOR SUNDAY- MONDAY THANKS TO A SOUTHWARD-CRASHING ARCTIC FRONT. ALTHOUGH IT MAY BE HARD FOR FOLKS TO BELIEVE IN THE WAKE OF TODAY/S WARMTH...HIGH TEMPERATURES ON SUNDAY WILL BE AN INCREDIBLE 40-50 DEGREES COLDER...AND ACCOMPANIED BY BRISK NORTH WINDS DRIVING DAYTIME WIND CHILLS DOWN IN THE ZERO TO 15 DEGREE RANGE IN MOST OF THE CWA...ESPECIALLY ON THE NEB SIDE. WHILE WINDS WILL DIMINISH FOR MONDAY...TEMPERATURES WILL REMAIN SIMILARLY COLD...BEFORE A DECENT- REBOUND TO NEAR-TO-SLIGHTLY-ABOVE NORMAL READINGS ENSUES FOR THE TUESDAY-FRIDAY TIME FRAME. NOT EXPECTING ANYTHING LIKE THE ONGOING WARMTH FOR MID-LATE NEXT WEEK...BUT AT LEAST MORE SEASONABLE HIGHS THAT WILL FEEL BETTER THAN SUNDAY-MONDAY WILL. PRECIPITATION-WISE...ALTHOUGH THE SHORT TERM FORECASTER OPTED TO INTRODUCE PATCHY FREEZING DRIZZLE POTENTIAL TO NORTHERN ZONES FOR LATE SATURDAY NIGHT...HAVE OPTED TO KEEP THE SUNDAY DAYTIME-SUNDAY NIGHT FORECAST "CLEAN" OF ANY PRECIPITATION MENTION FOR AT LEAST ONE MORE FORECAST CYCLE. ALTHOUGH THIS POSSIBILITY CERTAINLY CANNOT BE COMPLETELY RULED OUT...THERE SEEM TO BE ENOUGH NEGATIVES AGAINST IT TO KEEP IT OUT FOR NOW...AND LET LATER SHIFTS RE-EVALUATE ONCE THIS TIME FRAME GETS LESS THAN 24-36 HOURS AWAY. SEE BELOW FOR MORE ON THIS REASONING. OTHERWISE LOOKING FORWARD THROUGH THE MONDAY-FRIDAY TIME FRAME...CONFIDENCE IS REASONABLY HIGH THAT THE CURRENTLY DRY FORECAST IS JUSTIFIED FOR THE VAST MAJORITY OF THIS TIME...WITH THE ONLY FORESEEABLE CATCH POSSIBLY BEING AROUND THE WED NIGHT-THURSDAY TIME FRAME...WHEN THERE ARE HINTS THAT MAINLY OUR FAR EASTERN/SOUTHEAST ZONES COULD BE BRUSHED BY AN AREA OF LIQUID PRECIPITATION THAT APPEARS TO PRIMARILY AFFECT PARTS OF EASTERN KS/MO AND MAYBE FAR SOUTHEAST NEB. AT ANY RATE...THE DEFAULT MULTI- MODEL BLEND USED TO INITIALIZE THE FORECAST FOR THE DAY 4-7 TIME FRAME KEPT ANY MENTIONABLE PRECIP CHANCES AT LEAST 50-100 MILES EAST OF THE LOCAL AREA DURING THIS TIME FRAME...SO THUS THE CONTINUED DRY FORECAST. AS FOR WEATHER ELEMENTS PRESENTLY FORECAST TO BE WORTHY OF INCLUSION IN THE HAZARDOUS WEATHER OUTLOOK (HWOGID) DURING THESE 6 DAYS...THERE ARE CURRENTLY NONE. HOWEVER...AS USUAL THERE ARE A HANDFUL OF CAVEATS/"CLOSE CALLS" THAT COULD EVENTUALLY COME INTO PLAY...THE FIRST OF WHICH BEING IF IN FACT LIGHT FREEZING DRIZZLE ENDS UP IN SUNDAY/S FORECAST. WIND-WISE...ALTHOUGH IT WILL CERTAINLY BE WINDY SUNDAY BEHIND THE FRONT...SUSTAINED SPEEDS/GUSTS APPEAR TO LARGELY FALL A BIT SHORT OF 30 MPH/45 MPH RESPECTIVELY. ALONG THESE SAME LINES...ALTHOUGH AT LEAST SLIGHTLY SUB-ZERO WIND CHILLS ARE FORECAST ACROSS MUCH OF THE AREA SUNDAY NIGHT INTO MONDAY MORNING...THEY ARE EXPECTED TO REMAIN SAFELY ABOVE ADVISORY- CRITERIA OF -20. AS FOR FIRE WEATHER CONCERNS...IT IS WORTH NOTING THAT TUESDAY AFTERNOON BEARS WATCHING FOR POSSIBLY MEETING AT LEAST A NEAR-CRITICAL COMBINATION OF RELATIVE HUMIDITY FALLING BELOW 25 PERCENT AND SUSTAINED WINDS/GUSTS OF AT LEAST 15 MPH/20 MPH...ESPECIALLY IN WESTERN PARTS OF THE CWA. WE ARE STILL A FEW DAYS AWAY FROM GETTING A MORE DEFINITIVE HANDLE ON THIS...BUT OF ALL DAYS NEXT WEEK TUESDAY PROBABLY WARRANTS THE CLOSEST WATCHING FOR FIRE WEATHER. NOW TURNING TO A MORE DETAILED LOOK AT THE DAILY WEATHER IN 24-48 HOUR BLOCKS... SUNDAY DAYTIME-SUNDAY NIGHT...OBVIOUSLY THE BIG STORY HERE IS A RETURN TO LEGITIMATE WINTRY-COLD. BY SUNRISE...THE LEADING EDGES OF THE STRONG ARCTIC FRONT WILL HAVE PASSED THROUGH THE ENTIRE CWA...PAVING THE WAY FOR SEVERAL HOURS OF SUSTAINED NORTHERLY WINDS GENERALLY 20-25 MPH/GUSTS 30-35 MPH AND POSSIBLY A BRIEF TIME OF SPEEDS AT LEAST 5 MPH HIGHER YET AS 3-HOUR PRESSURE RISES OF AT LEAST 3-6 MILLIBARS POUR SOUTHWARD ACROSS THE AREA...ESPECIALLY IN THE MORNING. IN THE MID-UPPER LEVELS...THIS FRONT WILL BE DRIVEN SOUTHWARD BY A PAIR OF VIGOROUS SHORTWAVE TROUGHS AND UPPER JET STREAK TRANSLATING EASTWARD ACROSS THE DAKOTAS/SOUTH CENTRAL CANADA INTO THE GREAT LAKES OVER THE COURSE OF THESE 24 HOURS. PRECIP- WISE...ALREADY MENTIONED ABOVE THAT HAVE OPTED TO REFRAIN FROM ANY OFFICIAL MENTION OF FREEZING DRIZZLE/FLURRY FOR THIS TIME FRAME...BUT THIS BEARS WATCHING. ONE LIMITING FACTOR FOR ANYTHING MORE THAN A FEW ROGUE SPITS OF DRIZZLE APPEARS TO BE AN OVERALL-LACK OF DEEP LOW-LEVEL SATURATION FROM THE SURFACE UP TO AROUND 850MB/ROUGHLY 1KM...WHICH IS OFTEN MORE CONCERNING FOR DRIZZLE PRODUCTION. INSTEAD IN THIS CASE...THE INITIAL SURGE OF LOW STRATUS IMMEDIATELY BEHIND THE FRONT APPEARS TO BE A BIT TOO SHALLOW TO SUPPORT LEGIT DRIZZLE...WHILE AS SATURATION BRIEFLY DEEPENS TO AROUND 850MB WELL BEHIND THE INITIAL FRONTAL SURGE...THE VERY LOWEST LEVELS START TO DRY OUT. IT DOES APPEAR THAT PARTS OF NORTHERN/WESTERN NEB OUTSIDE THE CWA MAY BE SLIGHTLY MORE FAVORED TO OBSERVE LIGHT FREEZING DRIZZLE HOWEVER. AT ANY RATE...ALTHOUGH A FEW SPITS OF LIGHT FREEZING DRIZZLE CANNOT BE COMPLETELY RULED OUT MAINLY BEFORE NOON...JUST DON/T FEEL ITS WORTH A FORECAST MENTION ESPECIALLY GIVEN THAT IT WOULD BE UNLIKELY TO BECOME IMPACTFUL. OF COURSE...LATER MODEL DATA AND/OR FORECASTER JUDGMENT MAY CHANGE THINGS. BY LATER IN THE DAY AND ESPECIALLY SUNDAY NIGHT...THE LOW LEVELS BECOME COLD ENOUGH THAT ANY LIGHT FREEZING DRIZZLE THREAT WOULD ABATE ANYWAY...AND INSTEAD POSSIBLY TRANSITION TO A SLIGHT CHANCE OF FLURRIES/VERY LIGHT SNOW AS AN EAST-WEST BAND OF MODEST MID LEVEL CONVERGENCE/FRONTOGENESIS SINKS SOUTHWARD ACROSS THE AREA. HOWEVER...GIVEN THAT MODEL DATA OVERWHELMINGLY FOCUSES THIS FLURRY POTENTIAL FOR SUNDAY NIGHT OVER WESTERN PORTIONS OF NEB AND POSSIBLY NORTHWEST KS...WILL AGAIN OPT TO REFRAIN FROM A FORMAL MENTION LOCALLY AND DEFER TO LATER FORECASTS TO RE-EVALUATE IF NECESSARY. TEMPERATURE-WISE FOR SUNDAY...THERE COULD BE A SLIGHT DAYTIME RISE BUT NOT MUCH OF ONE...AND IF ANYTHING NUDGED DOWN HIGHS ANOTHER 1-3 DEGREES...AIMING FOR A RANGE FROM LOW 20S NORTH TO LOW 30S SOUTH. FOR LOWS SUNDAY NIGHT...FELT THAT RAW MET/MAV GUIDANCE LOOKED A TOUCH TOO COLD GIVEN THAT THERE COULD BE PLENTY OF MID LEVEL CLOUD COVER AND CONTINUED NORTHERLY BREEZES AVERAGING AT LEAST 10-15 MPH...SO STAYED JUST A BIT WARMER AND VERY CLOSE TO PREVIOUS FORECAST WITH MOST AREAS BOTTOMING OUT BETWEEN 7-13 DEGREES. MONDAY DAYTIME-MONDAY NIGHT...ANY POSSIBLE CHANCE OF FLURRY ACTIVITY SHOULD BE WANING BY THIS TIME AS THE ZONE OF MID LEVEL LIFT WEAKENS IN RESPONSE TO THE EASTWARD-SHIFT OF THE PARENT SHORTWAVE TROUGH/JET STREAK ACROSS THE GREAT LAKES/SOUTHEAST CANADA. AT THE SURFACE...THE DAY WILL START OUT WITH A STRONG HIGH PRESSURE SYSTEM AROUND 1045 MILLIBARS CENTERED OVER THE DAKOTAS...WHICH WILL STEADILY SHIFT INTO THE IA/MN/WI AREA BY DAYS END AND WELL-EAST INTO THE GREAT LAKES BY SUNRISE TUESDAY. IN OTHER WORDS...THE CORE OF THIS HIGH NEVER REALLY PASSES OVER THE LOCAL AREA. AS A RESULT...MONDAY WILL FEATURE LIGHTER WINDS THAN SUNDAY AS INITIALLY NORTHERLY BREEZES GRADUALLY TURN MORE EASTERLY THEN SOUTHERLY AS THE DAY WEARS ON BEHIND THE DEPARTING HIGH. GIVEN THE LINGERING COLD AIRMASS AND LACK OF DEEP MIXING...ACTUAL HIGH TEMPS MONDAY ARE FORECAST TO EXHIBIT AT-MOST ONLY LITTLE IMPROVEMENT VERSUS SUNDAY...AND HAVE A RANGE GOING FROM MID 20S NORTHEAST TO UPPER 20S/NEAR-30 SOUTHWEST. ON MONDAY NIGHT...A FAIRLY AGGRESSIVE WARM AIR ADVECTION REGIME SETS IN AND SURFACE WINDS INCREASE TO AT LEAST 10-15 MPH FROM THE SOUTH...WHICH COULD ACTUALLY RESULT IN STEADY TO SLIGHTLY-RISING TEMPS LATE IN THE NIGHT. HOWEVER MADE LITTLE CHANGE TO ACTUAL LOWS...AIMING MOST OF THE CWA RIGHT AROUND 15 DEGREES. TUESDAY DAYTIME-WEDNESDAY NIGHT...THE MAJORITY OF THIS 48 HOURS CARRIES HIGH CONFIDENCE IN STAYING DRY...UNLESS OF COURSE THE WESTERN EDGE OF LIGHT PRECIPITATION POTENTIAL MENTIONED ABOVE HAPPENS TO ENCROACH ON SOME OF OUR EASTERN COUNTIES WED NIGHT PER THE LATEST ECMWF SOLUTION. BY AND LARGE THOUGH...TEMPERATURES WILL BE THE MAIN STORY DURING THESE FEW DAYS. ON TUESDAY...STEADY SOUTHWESTERLY BREEZES ARE EXPECTED TO RESULT IN AT LEAST A 15+ DEGREE IMPROVEMENT VERSUS MONDAY...WITH HIGHS AIMED BACK INTO THE UPPER 30S-UPPER 40S RANGE. HOWEVER ALREADY BY TUESDAY NIGHT A WEAK COLD FRONT (MUCH WEAKER THAN THE SUNDAY ONE) DROPS DOWN ACROSS THE AREA IN RESPONSE TO THE PASSAGE OF ANOTHER SHORTWAVE TROUGH ACROSS THE NORTHERN PLAINS/GREAT LAKES AREA. ALTHOUGH THE LOCAL AREA CURRENTLY ONLY APPEARS TO RECEIVE A GLANCING BLOW OF COLDER AIR HERE...HIGHS WEDNESDAY SHOULD BE A FEW TICKS COOLER THAN TUESDAY IN NORTHEAST ZONES AND HAVE A RANGE FROM UPPER 30S NORTHEAST TO MID 40S SOUTHWEST. THURSDAY DAYTIME-FRIDAY DAYTIME...FOR THESE LAST 36 HOURS OF THE FORECAST THE LATEST 00Z RUNS OF THE ECMWF/GFS MODELS ARE ACTUALLY IN SURPRISINGLY-GOOD AGREEMENT ON THE LARGER SCALE PATTERN...WITH GENERALLY QUASI-ZONAL FLOW IN PLACE OVER THE CENTRAL PLAINS...AND DECENT AGREEMENT ON A LOW-AMPLITUDE DISTURBANCE PASSING OVER OR NEAR THE CWA FROM THURS INTO THURS NIGHT. HOWEVER AS MENTIONED ABOVE...THE VAST MAJORITY OF MODEL-GENERATED PRECIPITATION CURRENTLY FOCUSES SOUTH THROUGH EAST OF THE LOCAL AREA. CERTAINLY A SLIGHTLY MILDER THAN AVERAGE AIRMASS APPEARS TO REMAIN IN PLACE DURING THESE TWO DAYS...AND ONLY MINOR TWEAKS WERE MADE TO FORECAST HIGHS...WHICH ARE PRELIMINARILY AIMED SOMEWHERE INTO THE 40S FOR MOST AREAS ON BOTH DAYS...WITH FRIDAY POSSIBLY MORE FAVORED TO BREACH THE 50 MARK...ESPECIALLY IN SOUTHWEST ZONES. && .AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z SUN AFTERNOON) ISSUED AT 1142 AM CST SAT NOV 29 2014 THIS AFTERNOON: VFR CIRROSTRATUS CIGS AROUND 25K FT. LIGHT AND VARIABLE WINDS. CONFIDENCE: HIGH TONIGHT: VFR SHOULD DECAY TO MVFR WITH 1500 FT CIGS BEHIND AN ARCTIC COLD FRONT WHICH SHOULD MOVE THRU THE AIRPORTS IN THE 06Z- 08Z TIMEFRAME. ALL MODELS ARE NOT ON-BOARD WITH THESE MVFR CIGS BUT USED THE SIGNALS FROM FCST SOUNDINGS AND THE FACT THAT MVFR CIGS ARE UPSTREAM BEHIND THE FRONT (OVER SD/MT/ND). N WINDS WILL INCREASE AND G25 KTS AFTER FRONAL PASSAGE. CONFIDENCE: MEDIUM DUE TO UNCERTAINTY WITH TIMING OF THE FRONT AND MVFR CIGS. SUN THRU 18Z: MVFR CIGS PROBABLE THRU MOST OF THE MORNING SHOULD IMPROVE TO VFR 15Z-18Z. N WINDS GUST UP TO 35 KTS. CONFIDENCE: MEDIUM && .CLIMATE... WITH AN UNSEASONABLY WARM AIRMASS IN PLACE AND LIGHT WESTERLY FLOW ANTICIPATED...RECORD HIGH TEMPERATURES ARE FORECAST FOR THIS AFTERNOON. THE PREVIOUS RECORD HIGH TEMPERATURES AND FORECAST HIGH TEMPERATURES ARE DETAILED BELOW. GRAND ISLAND NEBRASKA: RECORD HIGH TEMPERATURE FOR NOVEMBER 29TH: 71F IN 1932 FORECAST HIGH TEMPERATURE FOR TODAY: 72F HASTINGS NEBRASKA: RECORD HIGH TEMPERATURE FOR NOVEMBER 29TH: 68F IN 2003 FORECAST HIGH TEMPERATURE FOR TODAY: 73F DESPITE THE RECORD WARMTH TO END THE MONTH...A STRETCH OF VERY COLD WEATHER EARLIER THIS MONTH WILL RESULT IN THE AVERAGE MONTHLY TEMPERATURE FOR NOVEMBER BEING ABOUT 5 DEGREES BELOW NORMAL...RANKING NOVEMBER 2014 AMONG THE TOP TWENTY COOLEST NOVEMBERS OF THE PAST 100 YEARS IN BOTH GRAND ISLAND AND HASTINGS. THE COOLEST NOVEMBER ON RECORD FOR BOTH GRAND ISLAND AND HASTING OCCURRED IN 1985...WHEN THE AVERAGE TEMPERATURE WAS NEARLY 10 DEGREES BELOW NORMAL AT BOTH SITES. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...ROSSI LONG TERM...PFANNKUCH AVIATION...HALBLAUB CLIMATE...ROSSI
AREA FORECAST DISCUSSION
NWS HASTINGS NE
925 AM CST SAT NOV 29 2014 .UPDATE... ISSUED AT 925 AM CST SAT NOV 29 2014 WE HAVE EVALUATED THE NEED FOR A RED FLAG WARNING N AND W OF THE TRI-CITIES FOR THIS AFTN. AM CONCERNED THAT THE NAM/GFS ARE UNDER-FORECASTING WINDS BASED ON THEIR UNREALISTICALLY LOW FCST MIXING HEIGHTS. THE RAP FCST SOUNDINGS SHOW WHAT WE THINK WILL HAPPEN WITH A TYPICAL UNSTABLE BL DEVELOPING. THAT MEANS WINDS WILL BE HIGHER THAN CURRENTLY FCST. THAT IS A PROBLEM BECAUSE POOR MODELING LOWERS CONFIDENCE. THERE IS A CHANCE WE MAY NEED TO ISSUE A SHORT LEAD-TIME RFW FOR VALLEY/SHERMAN COUNTIES AND POSSIBLY BUFFALO AND DAWSON. THE ONE MITIGATING FACTOR IS HIGH CLOUDS. THAT WILL INHIBIT MIXING. IT ALSO SOMEWHAT ENCOURAGING THAT THE ISOBARS ARE FAIRLY SPREAD APART OVER THE CNTRL PLAINS...IE A WEAK PRES GRAD. WE DID NOTE LBF EXPANDED THEIR RFD UP TO OUR NW/N BORDER. WE WILL CLOSELY MONITOR. THE FCST WILL BE UPDATED TO INCREASE WINDS SOME AND THE FIRE WX FCST WILL ALSO BE UPDATED TO INCREASE MIXING HGTS. UPDATE ISSUED AT 727 AM CST SAT NOV 29 2014 SENT AN ENHANCED SHORT-TERM FCST /ESTF/ UPDATE TO INCREASE SKY COVER TO P/CLOUDY. HOURLY FCST DWPTS WERE ALSO RUNNING TOO HIGH COMPARED TO REALITY. UPDATED FCST WILL POST SHORTLY WITH THESE ADJUSTMENTS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 423 AM CST SAT NOV 29 2014 PLENTY OF HIGH LEVEL CLOUD COVER IS SPILLING ACROSS THE CENTRAL PLAINS THIS MORNING...ASSOCIATED WITH AN UPPER LEVEL JET STREAK PUSHING ACROSS THE ROCKY MOUNTAINS. EXPECT THIS CLOUD COVER TO LINGER THROUGHOUT THE AFTERNOON...POTENTIALLY HOLDING DOWN HIGH TEMPERATURES A COUPLE OF DEGREES...BUT OTHERWISE HAVING LITTLE IMPACT. WITH LOW LEVEL WESTERLY FLOW CONTINUING ALONG WITH A VERY MILD AIRMASS IN PLACE...EXPECT THE POTENTIAL FOR ANOTHER EXTREMELY NICE FALL AFTERNOON ACROSS THE REGION...WITH RECORD HIGH TEMPERATURES CURRENTLY FORECAST FOR BOTH GRAND ISLAND AND HASTINGS. WHILE A BEAUTIFUL AFTERNOON IS IN STORE FOR THE REGION...CONDITIONS WILL CHANGE ABRUPTLY OVERNIGHT...AS A VERY STRONG COLD FRONT DROPS SOUTHWARD ACROSS THE PLAINS. MODEL DATA CONTINUES TO INDICATE OVER A 20C+ DROP IN TEMPS AT 850 BEHIND THIS FRONT...WITH THE LEADING EDGE OF THE COLD AIRMASS FORECAST TO REACH GRAND ISLAND AROUND MIDNIGHT. WITH THE VERY DENSE AND COLD NATURE OF THIS AIRMASS...WOULD NOT BE SURPRISED IF IT WILL BE ABLE TO RACE INTO NORTH CENTRAL KANSAS PRIOR TO DAWN SUNDAY MORNING...AND ADJUSTED LOW TEMPERATURES DOWN A COUPLE OF DEGREES TO COMPENSATE FOR THIS DESPITE THE STRONG NORTHERLY WINDS THAT ARE ANTICIPATED TO ACCOMPANY THIS FRONT. WHILE THERE IS ONLY VERY SHALLOW MOISTURE DEPICTED IN THE MODEL DATA...AND THE CLASSIC DRIZZLE SIGNATURE IS NOT EVIDENT IN PRECIP FIELDS...DID GO AHEAD AND ADD SOME PATCHY FREEZING DRIZZLE TO NORTHEASTERN PORTIONS OF THE FORECAST AREA DURING THE PRE-DAWN HOURS SUNDAY MORNING...AS THE NAM INDICATES A BIT OF LIFT IN THIS LOWEST LAYER...WHICH MAY BE JUST ENOUGH TO SQUEEZE OUT A FEW SMALL DROPS OF MOISTURE. THAT SAID...LITTLE ICE ACCUMULATION IS ANTICIPATED...AND DID NOT INSERT ANY QPF INTO THE FORECAST IN THE FORM OF EITHER LIQUID OR ICE FOR THE TIME BEING. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 423 AM CST SAT NOV 29 2014 TEMPERATURE WISE...AFTER BASKING IN NEAR-RECORD TO RECORD WARMTH FRIDAY AND TODAY...BY FAR THE BIGGEST STORY OF THIS 6-DAY PERIOD ARRIVES RIGHT AWAY IN THE FORM OF A MAJOR CHILL-DOWN FOR SUNDAY- MONDAY THANKS TO A SOUTHWARD-CRASHING ARCTIC FRONT. ALTHOUGH IT MAY BE HARD FOR FOLKS TO BELIEVE IN THE WAKE OF TODAY/S WARMTH...HIGH TEMPERATURES ON SUNDAY WILL BE AN INCREDIBLE 40-50 DEGREES COLDER...AND ACCOMPANIED BY BRISK NORTH WINDS DRIVING DAYTIME WIND CHILLS DOWN IN THE ZERO TO 15 DEGREE RANGE IN MOST OF THE CWA...ESPECIALLY ON THE NEB SIDE. WHILE WINDS WILL DIMINISH FOR MONDAY...TEMPERATURES WILL REMAIN SIMILARLY COLD...BEFORE A DECENT- REBOUND TO NEAR-TO-SLIGHTLY-ABOVE NORMAL READINGS ENSUES FOR THE TUESDAY-FRIDAY TIME FRAME. NOT EXPECTING ANYTHING LIKE THE ONGOING WARMTH FOR MID-LATE NEXT WEEK...BUT AT LEAST MORE SEASONABLE HIGHS THAT WILL FEEL BETTER THAN SUNDAY-MONDAY WILL. PRECIPITATION-WISE...ALTHOUGH THE SHORT TERM FORECASTER OPTED TO INTRODUCE PATCHY FREEZING DRIZZLE POTENTIAL TO NORTHERN ZONES FOR LATE SATURDAY NIGHT...HAVE OPTED TO KEEP THE SUNDAY DAYTIME-SUNDAY NIGHT FORECAST "CLEAN" OF ANY PRECIPITATION MENTION FOR AT LEAST ONE MORE FORECAST CYCLE. ALTHOUGH THIS POSSIBILITY CERTAINLY CANNOT BE COMPLETELY RULED OUT...THERE SEEM TO BE ENOUGH NEGATIVES AGAINST IT TO KEEP IT OUT FOR NOW...AND LET LATER SHIFTS RE-EVALUATE ONCE THIS TIME FRAME GETS LESS THAN 24-36 HOURS AWAY. SEE BELOW FOR MORE ON THIS REASONING. OTHERWISE LOOKING FORWARD THROUGH THE MONDAY-FRIDAY TIME FRAME...CONFIDENCE IS REASONABLY HIGH THAT THE CURRENTLY DRY FORECAST IS JUSTIFIED FOR THE VAST MAJORITY OF THIS TIME...WITH THE ONLY FORESEEABLE CATCH POSSIBLY BEING AROUND THE WED NIGHT-THURSDAY TIME FRAME...WHEN THERE ARE HINTS THAT MAINLY OUR FAR EASTERN/SOUTHEAST ZONES COULD BE BRUSHED BY AN AREA OF LIQUID PRECIPITATION THAT APPEARS TO PRIMARILY AFFECT PARTS OF EASTERN KS/MO AND MAYBE FAR SOUTHEAST NEB. AT ANY RATE...THE DEFAULT MULTI- MODEL BLEND USED TO INITIALIZE THE FORECAST FOR THE DAY 4-7 TIME FRAME KEPT ANY MENTIONABLE PRECIP CHANCES AT LEAST 50-100 MILES EAST OF THE LOCAL AREA DURING THIS TIME FRAME...SO THUS THE CONTINUED DRY FORECAST. AS FOR WEATHER ELEMENTS PRESENTLY FORECAST TO BE WORTHY OF INCLUSION IN THE HAZARDOUS WEATHER OUTLOOK (HWOGID) DURING THESE 6 DAYS...THERE ARE CURRENTLY NONE. HOWEVER...AS USUAL THERE ARE A HANDFUL OF CAVEATS/"CLOSE CALLS" THAT COULD EVENTUALLY COME INTO PLAY...THE FIRST OF WHICH BEING IF IN FACT LIGHT FREEZING DRIZZLE ENDS UP IN SUNDAY/S FORECAST. WIND-WISE...ALTHOUGH IT WILL CERTAINLY BE WINDY SUNDAY BEHIND THE FRONT...SUSTAINED SPEEDS/GUSTS APPEAR TO LARGELY FALL A BIT SHORT OF 30 MPH/45 MPH RESPECTIVELY. ALONG THESE SAME LINES...ALTHOUGH AT LEAST SLIGHTLY SUB-ZERO WIND CHILLS ARE FORECAST ACROSS MUCH OF THE AREA SUNDAY NIGHT INTO MONDAY MORNING...THEY ARE EXPECTED TO REMAIN SAFELY ABOVE ADVISORY- CRITERIA OF -20. AS FOR FIRE WEATHER CONCERNS...IT IS WORTH NOTING THAT TUESDAY AFTERNOON BEARS WATCHING FOR POSSIBLY MEETING AT LEAST A NEAR-CRITICAL COMBINATION OF RELATIVE HUMIDITY FALLING BELOW 25 PERCENT AND SUSTAINED WINDS/GUSTS OF AT LEAST 15 MPH/20 MPH...ESPECIALLY IN WESTERN PARTS OF THE CWA. WE ARE STILL A FEW DAYS AWAY FROM GETTING A MORE DEFINITIVE HANDLE ON THIS...BUT OF ALL DAYS NEXT WEEK TUESDAY PROBABLY WARRANTS THE CLOSEST WATCHING FOR FIRE WEATHER. NOW TURNING TO A MORE DETAILED LOOK AT THE DAILY WEATHER IN 24-48 HOUR BLOCKS... SUNDAY DAYTIME-SUNDAY NIGHT...OBVIOUSLY THE BIG STORY HERE IS A RETURN TO LEGITIMATE WINTRY-COLD. BY SUNRISE...THE LEADING EDGES OF THE STRONG ARCTIC FRONT WILL HAVE PASSED THROUGH THE ENTIRE CWA...PAVING THE WAY FOR SEVERAL HOURS OF SUSTAINED NORTHERLY WINDS GENERALLY 20-25 MPH/GUSTS 30-35 MPH AND POSSIBLY A BRIEF TIME OF SPEEDS AT LEAST 5 MPH HIGHER YET AS 3-HOUR PRESSURE RISES OF AT LEAST 3-6 MILLIBARS POUR SOUTHWARD ACROSS THE AREA...ESPECIALLY IN THE MORNING. IN THE MID-UPPER LEVELS...THIS FRONT WILL BE DRIVEN SOUTHWARD BY A PAIR OF VIGOROUS SHORTWAVE TROUGHS AND UPPER JET STREAK TRANSLATING EASTWARD ACROSS THE DAKOTAS/SOUTH CENTRAL CANADA INTO THE GREAT LAKES OVER THE COURSE OF THESE 24 HOURS. PRECIP- WISE...ALREADY MENTIONED ABOVE THAT HAVE OPTED TO REFRAIN FROM ANY OFFICIAL MENTION OF FREEZING DRIZZLE/FLURRY FOR THIS TIME FRAME...BUT THIS BEARS WATCHING. ONE LIMITING FACTOR FOR ANYTHING MORE THAN A FEW ROGUE SPITS OF DRIZZLE APPEARS TO BE AN OVERALL-LACK OF DEEP LOW-LEVEL SATURATION FROM THE SURFACE UP TO AROUND 850MB/ROUGHLY 1KM...WHICH IS OFTEN MORE CONCERNING FOR DRIZZLE PRODUCTION. INSTEAD IN THIS CASE...THE INITIAL SURGE OF LOW STRATUS IMMEDIATELY BEHIND THE FRONT APPEARS TO BE A BIT TOO SHALLOW TO SUPPORT LEGIT DRIZZLE...WHILE AS SATURATION BRIEFLY DEEPENS TO AROUND 850MB WELL BEHIND THE INITIAL FRONTAL SURGE...THE VERY LOWEST LEVELS START TO DRY OUT. IT DOES APPEAR THAT PARTS OF NORTHERN/WESTERN NEB OUTSIDE THE CWA MAY BE SLIGHTLY MORE FAVORED TO OBSERVE LIGHT FREEZING DRIZZLE HOWEVER. AT ANY RATE...ALTHOUGH A FEW SPITS OF LIGHT FREEZING DRIZZLE CANNOT BE COMPLETELY RULED OUT MAINLY BEFORE NOON...JUST DON/T FEEL ITS WORTH A FORECAST MENTION ESPECIALLY GIVEN THAT IT WOULD BE UNLIKELY TO BECOME IMPACTFUL. OF COURSE...LATER MODEL DATA AND/OR FORECASTER JUDGMENT MAY CHANGE THINGS. BY LATER IN THE DAY AND ESPECIALLY SUNDAY NIGHT...THE LOW LEVELS BECOME COLD ENOUGH THAT ANY LIGHT FREEZING DRIZZLE THREAT WOULD ABATE ANYWAY...AND INSTEAD POSSIBLY TRANSITION TO A SLIGHT CHANCE OF FLURRIES/VERY LIGHT SNOW AS AN EAST-WEST BAND OF MODEST MID LEVEL CONVERGENCE/FRONTOGENESIS SINKS SOUTHWARD ACROSS THE AREA. HOWEVER...GIVEN THAT MODEL DATA OVERWHELMINGLY FOCUSES THIS FLURRY POTENTIAL FOR SUNDAY NIGHT OVER WESTERN PORTIONS OF NEB AND POSSIBLY NORTHWEST KS...WILL AGAIN OPT TO REFRAIN FROM A FORMAL MENTION LOCALLY AND DEFER TO LATER FORECASTS TO RE-EVALUATE IF NECESSARY. TEMPERATURE-WISE FOR SUNDAY...THERE COULD BE A SLIGHT DAYTIME RISE BUT NOT MUCH OF ONE...AND IF ANYTHING NUDGED DOWN HIGHS ANOTHER 1-3 DEGREES...AIMING FOR A RANGE FROM LOW 20S NORTH TO LOW 30S SOUTH. FOR LOWS SUNDAY NIGHT...FELT THAT RAW MET/MAV GUIDANCE LOOKED A TOUCH TOO COLD GIVEN THAT THERE COULD BE PLENTY OF MID LEVEL CLOUD COVER AND CONTINUED NORTHERLY BREEZES AVERAGING AT LEAST 10-15 MPH...SO STAYED JUST A BIT WARMER AND VERY CLOSE TO PREVIOUS FORECAST WITH MOST AREAS BOTTOMING OUT BETWEEN 7-13 DEGREES. MONDAY DAYTIME-MONDAY NIGHT...ANY POSSIBLE CHANCE OF FLURRY ACTIVITY SHOULD BE WANING BY THIS TIME AS THE ZONE OF MID LEVEL LIFT WEAKENS IN RESPONSE TO THE EASTWARD-SHIFT OF THE PARENT SHORTWAVE TROUGH/JET STREAK ACROSS THE GREAT LAKES/SOUTHEAST CANADA. AT THE SURFACE...THE DAY WILL START OUT WITH A STRONG HIGH PRESSURE SYSTEM AROUND 1045 MILLIBARS CENTERED OVER THE DAKOTAS...WHICH WILL STEADILY SHIFT INTO THE IA/MN/WI AREA BY DAYS END AND WELL-EAST INTO THE GREAT LAKES BY SUNRISE TUESDAY. IN OTHER WORDS...THE CORE OF THIS HIGH NEVER REALLY PASSES OVER THE LOCAL AREA. AS A RESULT...MONDAY WILL FEATURE LIGHTER WINDS THAN SUNDAY AS INITIALLY NORTHERLY BREEZES GRADUALLY TURN MORE EASTERLY THEN SOUTHERLY AS THE DAY WEARS ON BEHIND THE DEPARTING HIGH. GIVEN THE LINGERING COLD AIRMASS AND LACK OF DEEP MIXING...ACTUAL HIGH TEMPS MONDAY ARE FORECAST TO EXHIBIT AT-MOST ONLY LITTLE IMPROVEMENT VERSUS SUNDAY...AND HAVE A RANGE GOING FROM MID 20S NORTHEAST TO UPPER 20S/NEAR-30 SOUTHWEST. ON MONDAY NIGHT...A FAIRLY AGGRESSIVE WARM AIR ADVECTION REGIME SETS IN AND SURFACE WINDS INCREASE TO AT LEAST 10-15 MPH FROM THE SOUTH...WHICH COULD ACTUALLY RESULT IN STEADY TO SLIGHTLY-RISING TEMPS LATE IN THE NIGHT. HOWEVER MADE LITTLE CHANGE TO ACTUAL LOWS...AIMING MOST OF THE CWA RIGHT AROUND 15 DEGREES. TUESDAY DAYTIME-WEDNESDAY NIGHT...THE MAJORITY OF THIS 48 HOURS CARRIES HIGH CONFIDENCE IN STAYING DRY...UNLESS OF COURSE THE WESTERN EDGE OF LIGHT PRECIPITATION POTENTIAL MENTIONED ABOVE HAPPENS TO ENCROACH ON SOME OF OUR EASTERN COUNTIES WED NIGHT PER THE LATEST ECMWF SOLUTION. BY AND LARGE THOUGH...TEMPERATURES WILL BE THE MAIN STORY DURING THESE FEW DAYS. ON TUESDAY...STEADY SOUTHWESTERLY BREEZES ARE EXPECTED TO RESULT IN AT LEAST A 15+ DEGREE IMPROVEMENT VERSUS MONDAY...WITH HIGHS AIMED BACK INTO THE UPPER 30S-UPPER 40S RANGE. HOWEVER ALREADY BY TUESDAY NIGHT A WEAK COLD FRONT (MUCH WEAKER THAN THE SUNDAY ONE) DROPS DOWN ACROSS THE AREA IN RESPONSE TO THE PASSAGE OF ANOTHER SHORTWAVE TROUGH ACROSS THE NORTHERN PLAINS/GREAT LAKES AREA. ALTHOUGH THE LOCAL AREA CURRENTLY ONLY APPEARS TO RECEIVE A GLANCING BLOW OF COLDER AIR HERE...HIGHS WEDNESDAY SHOULD BE A FEW TICKS COOLER THAN TUESDAY IN NORTHEAST ZONES AND HAVE A RANGE FROM UPPER 30S NORTHEAST TO MID 40S SOUTHWEST. THURSDAY DAYTIME-FRIDAY DAYTIME...FOR THESE LAST 36 HOURS OF THE FORECAST THE LATEST 00Z RUNS OF THE ECMWF/GFS MODELS ARE ACTUALLY IN SURPRISINGLY-GOOD AGREEMENT ON THE LARGER SCALE PATTERN...WITH GENERALLY QUASI-ZONAL FLOW IN PLACE OVER THE CENTRAL PLAINS...AND DECENT AGREEMENT ON A LOW-AMPLITUDE DISTURBANCE PASSING OVER OR NEAR THE CWA FROM THURS INTO THURS NIGHT. HOWEVER AS MENTIONED ABOVE...THE VAST MAJORITY OF MODEL-GENERATED PRECIPITATION CURRENTLY FOCUSES SOUTH THROUGH EAST OF THE LOCAL AREA. CERTAINLY A SLIGHTLY MILDER THAN AVERAGE AIRMASS APPEARS TO REMAIN IN PLACE DURING THESE TWO DAYS...AND ONLY MINOR TWEAKS WERE MADE TO FORECAST HIGHS...WHICH ARE PRELIMINARILY AIMED SOMEWHERE INTO THE 40S FOR MOST AREAS ON BOTH DAYS...WITH FRIDAY POSSIBLY MORE FAVORED TO BREACH THE 50 MARK...ESPECIALLY IN SOUTHWEST ZONES. && .AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 550 AM CST SAT NOV 29 2014 PREVAILING VFR CONDITIONS ARE EXPECTED AT BOTH TERMINALS FOR THE NEXT 24 HOURS...WITH GENERALLY LIGHT WEST TO SOUTHWESTERLY WINDS AND PASSING HIGH CLOUDS EXPECTED THROUGHOUT THE DAY. TOWARDS THE TAIL END OF THE TAF PERIOD...EXPECT WINDS TO BEGIN TO SHIFT AND BECOME MORE WEST TO NORTHWESTERLY AHEAD OF A STRONG COLD FRONT...WHICH IS EXPECTED TO REACH THE TERMINALS AROUND 30/09Z...BRINGING A MID LEVEL CLOUD DECK NEAR 10KFT ALONG WITH GUSTY NORTHWESTELRY WINDS. && .CLIMATE... WITH AN UNSEASONABLY WARM AIRMASS IN PLACE AND LIGHT WESTERLY FLOW ANTICIPATED...RECORD HIGH TEMPERATURES ARE FORECAST FOR THIS AFTERNOON. THE PREVIOUS RECORD HIGH TEMPERATURES AND FORECAST HIGH TEMPERATURES ARE DETAILED BELOW. GRAND ISLAND NEBRASKA: RECORD HIGH TEMPERATURE FOR NOVEMBER 29TH: 71F IN 1932 FORECAST HIGH TEMPERATURE FOR TODAY: 72F HASTINGS NEBRASKA: RECORD HIGH TEMPERATURE FOR NOVEMBER 29TH: 68F IN 2003 FORECAST HIGH TEMPERATURE FOR TODAY: 73F DESPITE THE RECORD WARMTH TO END THE MONTH...A STRETCH OF VERY COLD WEATHER EARLIER THIS MONTH WILL RESULT IN THE AVERAGE MONTHLY TEMPERATURE FOR NOVEMBER BEING ABOUT 5 DEGREES BELOW NORMAL...RANKING NOVEMBER 2014 AMONG THE TOP TWENTY COOLEST NOVEMBERS OF THE PAST 100 YEARS IN BOTH GRAND ISLAND AND HASTINGS. THE COOLEST NOVEMBER ON RECORD FOR BOTH GRAND ISLAND AND HASTING OCCURRED IN 1985...WHEN THE AVERAGE TEMPERATURE WAS NEARLY 10 DEGREES BELOW NORMAL AT BOTH SITES. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...ROSSI LONG TERM...PFANNKUCH AVIATION...ROSSI CLIMATE...ROSSI
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
923 AM CST SAT NOV 29 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 400 AM CST SAT NOV 29 2014 DESPITE THE CIRRUS YESTERDAY TEMPERATURES ROSE INTO THE 70S. FOR TODAY...THE MODELS SUGGEST SOMEWHAT LESS HIGH CLOUDINESS AND THE TEMPERATURE FORECAST REFLECTS THE WARMER GUIDANCE CALLING FOR 70S AND RECORD HIGHS IN MANY AREAS. ALL MODELS EXCEPT THE FASTER ECM SHOW THE ARCTIC FRONT MOVING INTO NRN NEB BY OR AT 03Z TONIGHT. NOTE THE FASTER ECM SHOWS THE FRONT INTO NRN NEB BEFORE 00Z BUT STILL FORECASTS A HIGH OF 63F AT VALENTINE WITH TEMPERATURES FALLING TO 30F BY 00Z SO THIS FASTER TIMING COULD HAVE QUITE THE IMPACT LATE THIS AFTN ACROSS THE NORTH. THE FRONT SAGGED THROUGH KBIL AT 08Z AND THEY FELL 23 DEGREES IN ONE HOUR. THE NAM AND TO A CERTAIN EXTENT THE NMM AND ARW MODELS SHOW A NARROW 20 MILE OR SO WIDE BANK OF FOG FORMING ALONG THE LEADING EDGE OF THE ARCTIC AIR TONIGHT. THIS AIR MASS IS VERY SHALLOW AND QUICKLY COOLS TO SATURATION FOR AN HOUR OR TWO. THE ARCTIC FOG WOULD LIKELY PRODUCE SOME LIGHT FREEZING DRIZZLE OR FREEZING FOG FOR ABOUT AN HOUR. AT THIS TIME...GIVEN THE WARM GROUND THE DRIZZLE OR FOG IS BELIEVED TO BE TOO BRIEF AND LIGHT TO PRODUCE AN OBVIOUS TRAVEL HAZARD. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 400 AM CST SAT NOV 29 2014 REALITY HITS THAT IT IS ALMOST DECEMBER. AFTER A COUPLE OF DAYS WITH HIGHS IN THE 60S AND 70S...TEMPS WILL STRUGGLE TO GO ANYWHERE ON SUNDAY. THE STRONG ARCTIC FRONT WILL BE SOUTH OF THE AREA BY SUNDAY MORNING...WITH STRONG CAA DURING THE DAY. THIS WILL LIMIT THE REBOUNDING OF TEMPS...AND GUIDANCE ONLY HAS HIGHS IN THE TEENS AND 20S. THIS WILL BE 40 TO 50 DEGREES COOLER THAN TODAY. THERE IS THE POSSIBILITY TEMPS MAYBE TWO HIGH...AS FORECAST FOLLOWS GUIDANCE IN WARMING UP AROUND 5 DEGREES DURING THE AFTERNOON. WILL HAVE TO MONITOR AREAS TO THE NORTH TODAY TO SEE IF THERE IS ANY REBOUND OF TEMPS...IT COULD BE A DAY WHERE TEMPS HOLD STEADY OR EVEN FALL DURING THE AFTERNOON. ANOTHER CONCERN WILL BE LIGHT SNOW/FLURRIES. A BAND OF WEAK LIFT FOLLOWS IN THE WAKE OF THE FRONT...ALTHOUGH THE BAND IS IN A DEEP AND FAVORED DENDRITIC GROWTH ZONE. HAVE INCLUDED SOME FLURRIES ACROSS THE AREA...HOWEVER DOWNWIND OF THE BLACK HILLS...COULD SEE SOME LIGHT SNOW ACCUMULATION AND INCLUDED SLIGHT CHANCE POPS. WITH THE WARMING DURING THE DAY...DECIDED TO END THE FLURRIES. A FRONTOGENISIS BAND DEVELOPS SUNDAY EVENING INTO SUNDAY NIGHT AS A MID LEVEL DISTURBANCE CROSS THE CENTRAL ROCKIES. BEST CHANCE FOR SNOW IS ACROSS THE SE PANHANDLE INTO THE SOUTHERN SANDHILLS...WITH GOOD MODEL AGREEMENT OF AT LEAST SOME LIGHT /LESS THAN AN INCH/ ACCUMULATION. MEANWHILE THE SURFACE HIGH NOSES DOWN THE NORTHERN PLAINS. SOME CLEARING IS EXPECTED BY MONDAY MORNING ACROSS THE NORTH...AND TEMPS PLUMMET. LOWS MONDAY MORN ACROSS THE NORTH ARE EXPECTED EITHER SIDE OF 0 DEGREES...WITH SLIGHTLY WARMER TEMPS ACROSS THE SOUTH AS CLOUDS LINGER A LITTLE LONGER. IF ANY AREAS GET AN INCH OF SNOW...TEMPS COULD DROP WELL BELOW ZERO. BY MONDAY AFTERNOON THE HIGH WILL SHIFT OVER SRN MINN/NRN IA. COLD AIR IS SHALLOW AND WILL ALREADY BEGIN TO SEE A REBOUND OF TEMPS FOR MONDAY. STILL COLD WITH MOST AREAS IN THE 20S TO AROUND FREEZING. THE WARM UP CONTINUES FOR TUESDAY WITH 850 TEMPS BACK ABOVE 10 C FOR SW NEB. THIS WILL COMBINE WITH SOME SUN TO PUSH TEMPS ABOVE 50S...STILL IN THE 40S ACROSS THE NORTHEASTERN ZONES. A WEAK PACIFIC FRONT PUSH ACROSS THE AREA TUESDAY NIGHT. A COOL OFF INTO THE 30S AND LOWER 40S IS EXPECTED FOR WEDNESDAY. THE COOL DOWN IS SHORT LIVE AS TEMPS WARM BACK INTO THE 40S AND LOWER 50S FOR THURSDAY AND FRIDAY. AS FOR PRECIP CHANCES...MUCH OF THE WEEK IS DRY. THE MID WEEK PACIFIC FRONT IS FAST MOVING AND LOWER LEVEL MOISTURE IS LIMITED. TOP DOWN SATURATION IS EXPECTED...HOWEVER THE QUICK PACE WILL NOT ALLOW FOR SATURATION TO THE SURFACE...THUS ONLY AN INCREASE OF CLOUDS IS ANTICIPATED AT THIS TIME. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 525 AM CST SAT NOV 29 2014 VFR IS EXPECTED UNTIL 03Z TONIGHT. THEREAFTER AND ARCTIC FRONT WILL BEGIN MOVING THROUGH THE FCST AREA. A 1 TO 2 HOUR PERIOD OF LIFR IS INDICATED IN THE RAP AND NAM MODELS FOLLOWED BY PREVAILING MVFR/IFR CIGS. && .FIRE WEATHER... ISSUED AT 922 AM CST SAT NOV 29 2014 THE RFW WAS EXPANDED THIS MORNING TO INCLUDE FIRE ZONES 204...206...208 AND 209. THIS CURRENT WARNING REMAINS IN EFFECT UNTIL 6 PM CST. THE CONCERN LIES WITH THE DEVELOPMENT OF WESTERLY DOWNSLOPING WINDS LATER THIS MORNING...WHICH AS WAS THE CASE YESTERDAY...HELPED PUSH TEMPERATURES TO NEAR RECORD VALUES. THE SHORT TERM MODELS CONTINUE TO INDICATE TEMPERATURES OF WELL INTO THE 60S TO LOWER 70S THIS AFTERNOON...AND WHEN COMBINED WITH AN ABNORMALLY DRY AIRMASS WITH ORIGINS OFF THE ROCKIES...RELATIVE HUMIDITY VALUES OF 15% OR LOWER APPEAR LIKELY. THE QUESTION REMAINS AS TO HOW STRONG THE WIND WILL EVENTUALLY GET...YESTERDAY UNDER DENSE CIRRUS CONDITIONS THE MODELS STRUGGLED WITH THE AMOUNT OF MIXING AND COMPLETELY UNDER-ESTIMATED THE GUST POTENTIAL. CIRRUS IS OVER MUCH OF THE WARNING AREA TODAY...BUT WE STILL HAVE ENOUGH CONFIDENCE THAT PERIODIC GUSTS OF 25 MPH OR GREATER WILL OCCUR. IN ADDITION...SUFFICIENT MIXING OVERNIGHT HELPED KEEP MUCH OF THE SANDHILLS FROM DECOUPLING...RH RECOVERY WAS EXTREMELY POOR. THE EXPANSION OF THE RED FLAG WARNING CONSIDERED THE POOR RH RECOVERY AND THE FACT THAT A COLD FRONT IS ANTICIPATED THIS EVENING...PROVIDING FOR A DISTINCT WIND SHIFT TO THE NORTH. && .CLIMATE... ISSUED AT 400 AM CST SAT NOV 29 2014 NORTH PLATTE SET A NEW RECORD YESTERDAY WITH A HIGH OF 73...AND IMPERIAL TIED IT WITH A HIGH OF 74. TODAY RECORDS ARE 71 /1932/ AT NORTH PLATTE...75 /1901/ AT IMPERIAL...69 /1998 AND 1932/ AT BROKEN BOW...AND 74 /1932/ AT VALENTINE. THE VALENTINE RECORD APPEARS SAFE...HOWEVER THE OTHERS ARE IN JEOPARDY. && .LBF WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 6 PM CST /5 PM MST/ THIS EVENING FOR NEZ204-206-208-209. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...CDC FIRE WEATHER...JACOBS/TAYLOR CLIMATE...MASEK
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
525 AM CST SAT NOV 29 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 400 AM CST SAT NOV 29 2014 DESPITE THE CIRRUS YESTERDAY TEMPERATURES ROSE INTO THE 70S. FOR TODAY...THE MODELS SUGGEST SOMEWHAT LESS HIGH CLOUDINESS AND THE TEMPERATURE FORECAST REFLECTS THE WARMER GUIDANCE CALLING FOR 70S AND RECORD HIGHS IN MANY AREAS. ALL MODELS EXCEPT THE FASTER ECM SHOW THE ARCTIC FRONT MOVING INTO NRN NEB BY OR AT 03Z TONIGHT. NOTE THE FASTER ECM SHOWS THE FRONT INTO NRN NEB BEFORE 00Z BUT STILL FORECASTS A HIGH OF 63F AT VALENTINE WITH TEMPERATURES FALLING TO 30F BY 00Z SO THIS FASTER TIMING COULD HAVE QUITE THE IMPACT LATE THIS AFTN ACROSS THE NORTH. THE FRONT SAGGED THROUGH KBIL AT 08Z AND THEY FELL 23 DEGREES IN ONE HOUR. THE NAM AND TO A CERTAIN EXTENT THE NMM AND ARW MODELS SHOW A NARROW 20 MILE OR SO WIDE BANK OF FOG FORMING ALONG THE LEADING EDGE OF THE ARCTIC AIR TONIGHT. THIS AIR MASS IS VERY SHALLOW AND QUICKLY COOLS TO SATURATION FOR AN HOUR OR TWO. THE ARCTIC FOG WOULD LIKELY PRODUCE SOME LIGHT FREEZING DRIZZLE OR FREEZING FOG FOR ABOUT AN HOUR. AT THIS TIME...GIVEN THE WARM GROUND THE DRIZZLE OR FOG IS BELIEVED TO BE TOO BRIEF AND LIGHT TO PRODUCE AN OBVIOUS TRAVEL HAZARD. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 400 AM CST SAT NOV 29 2014 REALITY HITS THAT IT IS ALMOST DECEMBER. AFTER A COUPLE OF DAYS WITH HIGHS IN THE 60S AND 70S...TEMPS WILL STRUGGLE TO GO ANYWHERE ON SUNDAY. THE STRONG ARCTIC FRONT WILL BE SOUTH OF THE AREA BY SUNDAY MORNING...WITH STRONG CAA DURING THE DAY. THIS WILL LIMIT THE REBOUNDING OF TEMPS...AND GUIDANCE ONLY HAS HIGHS IN THE TEENS AND 20S. THIS WILL BE 40 TO 50 DEGREES COOLER THAN TODAY. THERE IS THE POSSIBILITY TEMPS MAYBE TWO HIGH...AS FORECAST FOLLOWS GUIDANCE IN WARMING UP AROUND 5 DEGREES DURING THE AFTERNOON. WILL HAVE TO MONITOR AREAS TO THE NORTH TODAY TO SEE IF THERE IS ANY REBOUND OF TEMPS...IT COULD BE A DAY WHERE TEMPS HOLD STEADY OR EVEN FALL DURING THE AFTERNOON. ANOTHER CONCERN WILL BE LIGHT SNOW/FLURRIES. A BAND OF WEAK LIFT FOLLOWS IN THE WAKE OF THE FRONT...ALTHOUGH THE BAND IS IN A DEEP AND FAVORED DENDRITIC GROWTH ZONE. HAVE INCLUDED SOME FLURRIES ACROSS THE AREA...HOWEVER DOWNWIND OF THE BLACK HILLS...COULD SEE SOME LIGHT SNOW ACCUMULATION AND INCLUDED SLIGHT CHANCE POPS. WITH THE WARMING DURING THE DAY...DECIDED TO END THE FLURRIES. A FRONTOGENISIS BAND DEVELOPS SUNDAY EVENING INTO SUNDAY NIGHT AS A MID LEVEL DISTURBANCE CROSS THE CENTRAL ROCKIES. BEST CHANCE FOR SNOW IS ACROSS THE SE PANHANDLE INTO THE SOUTHERN SANDHILLS...WITH GOOD MODEL AGREEMENT OF AT LEAST SOME LIGHT /LESS THAN AN INCH/ ACCUMULATION. MEANWHILE THE SURFACE HIGH NOSES DOWN THE NORTHERN PLAINS. SOME CLEARING IS EXPECTED BY MONDAY MORNING ACROSS THE NORTH...AND TEMPS PLUMMET. LOWS MONDAY MORN ACROSS THE NORTH ARE EXPECTED EITHER SIDE OF 0 DEGREES...WITH SLIGHTLY WARMER TEMPS ACROSS THE SOUTH AS CLOUDS LINGER A LITTLE LONGER. IF ANY AREAS GET AN INCH OF SNOW...TEMPS COULD DROP WELL BELOW ZERO. BY MONDAY AFTERNOON THE HIGH WILL SHIFT OVER SRN MINN/NRN IA. COLD AIR IS SHALLOW AND WILL ALREADY BEGIN TO SEE A REBOUND OF TEMPS FOR MONDAY. STILL COLD WITH MOST AREAS IN THE 20S TO AROUND FREEZING. THE WARM UP CONTINUES FOR TUESDAY WITH 850 TEMPS BACK ABOVE 10 C FOR SW NEB. THIS WILL COMBINE WITH SOME SUN TO PUSH TEMPS ABOVE 50S...STILL IN THE 40S ACROSS THE NORTHEASTERN ZONES. A WEAK PACIFIC FRONT PUSH ACROSS THE AREA TUESDAY NIGHT. A COOL OFF INTO THE 30S AND LOWER 40S IS EXPECTED FOR WEDNESDAY. THE COOL DOWN IS SHORT LIVE AS TEMPS WARM BACK INTO THE 40S AND LOWER 50S FOR THURSDAY AND FRIDAY. AS FOR PRECIP CHANCES...MUCH OF THE WEEK IS DRY. THE MID WEEK PACIFIC FRONT IS FAST MOVING AND LOWER LEVEL MOISTURE IS LIMITED. TOP DOWN SATURATION IS EXPECTED...HOWEVER THE QUICK PACE WILL NOT ALLOW FOR SATURATION TO THE SURFACE...THUS ONLY AN INCREASE OF CLOUDS IS ANTICIPATED AT THIS TIME. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 525 AM CST SAT NOV 29 2014 VFR IS EXPECTED UNTIL 03Z TONIGHT. THEREAFTER AND ARCTIC FRONT WILL BEGIN MOVING THROUGH THE FCST AREA. A 1 TO 2 HOUR PERIOD OF LIFR IS INDICATED IN THE RAP AND NAM MODELS FOLLOWED BY PREVAILING MVFR/IFR CIGS. && .FIRE WEATHER... ISSUED AT 400 AM CST SAT NOV 29 2014 ALL OF THE GUIDANCE...THE NAMDNG...HRRR...MOSGUIDE AND THE RAP SHOW STRONG WIND GUST POTENTIAL TODAY ACROSS THE NORTH. THE NAM SHOWS WIND GUSTS TO 35 KT AT KVTN. AT 08Z...KLNX RADAR SHOWS 40 KT WEST WINDS AT 1000 FT AGL. A BLEND OF WIND GUST CLIMO AND THE NAM MODEL PRODUCES WIND GUSTS TO 35 MPH ACROSS THE NORTH. A BLEND OF THE VERY DRY RAP DEWPOINTS AND THE OTHER MODELS PRODUCES DEWPOINTS AROUND 20F ACROSS THE SANDHILLS THIS AFTN WITH MAX TEMPS NEAR 70. RED FLAG CONDITIONS ARE EXPECTED TO DEVELOP THIS AFTERNOON ACROSS THE CENTRAL SANDHILLS. && .CLIMATE... ISSUED AT 400 AM CST SAT NOV 29 2014 NORTH PLATTE SET A NEW RECORD YESTERDAY WITH A HIGH OF 73...AND IMPERIAL TIED IT WITH A HIGH OF 74. TODAY RECORDS ARE 71 /1932/ AT NORTH PLATTE...75 /1901/ AT IMPERIAL...69 /1998 AND 1932/ AT BROKEN BOW...AND 74 /1932/ AT VALENTINE. THE VALENTINE RECORD APPEARS SAFE...HOWEVER THE OTHERS ARE IN JEOPARDY. && .LBF WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM NOON TODAY TO 6 PM CST THIS EVENING FOR NEZ206. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...CDC FIRE WEATHER...CDC CLIMATE...MASEK
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
405 AM CST SAT NOV 29 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 400 AM CST SAT NOV 29 2014 DESPITE THE CIRRUS YESTERDAY TEMPERATURES ROSE INTO THE 70S. FOR TODAY...THE MODELS SUGGEST SOMEWHAT LESS HIGH CLOUDINESS AND THE TEMPERATURE FORECAST REFLECTS THE WARMER GUIDANCE CALLING FOR 70S AND RECORD HIGHS IN MANY AREAS. ALL MODELS EXCEPT THE FASTER ECM SHOW THE ARCTIC FRONT MOVING INTO NRN NEB BY OR AT 03Z TONIGHT. NOTE THE FASTER ECM SHOWS THE FRONT INTO NRN NEB BEFORE 00Z BUT STILL FORECASTS A HIGH OF 63F AT VALENTINE WITH TEMPERATURES FALLING TO 30F BY 00Z SO THIS FASTER TIMING COULD HAVE QUITE THE IMPACT LATE THIS AFTN ACROSS THE NORTH. THE FRONT SAGGED THROUGH KBIL AT 08Z AND THEY FELL 23 DEGREES IN ONE HOUR. THE NAM AND TO A CERTAIN EXTENT THE NMM AND ARW MODELS SHOW A NARROW 20 MILE OR SO WIDE BANK OF FOG FORMING ALONG THE LEADING EDGE OF THE ARCTIC AIR TONIGHT. THIS AIR MASS IS VERY SHALLOW AND QUICKLY COOLS TO SATURATION FOR AN HOUR OR TWO. THE ARCTIC FOG WOULD LIKELY PRODUCE SOME LIGHT FREEZING DRIZZLE OR FREEZING FOG FOR ABOUT AN HOUR. AT THIS TIME...GIVEN THE WARM GROUND THE DRIZZLE OR FOG IS BELIEVED TO BE TOO BRIEF AND LIGHT TO PRODUCE AN OBVIOUS TRAVEL HAZARD. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 400 AM CST SAT NOV 29 2014 REALITY HITS THAT IT IS ALMOST DECEMBER. AFTER A COUPLE OF DAYS WITH HIGHS IN THE 60S AND 70S...TEMPS WILL STRUGGLE TO GO ANYWHERE ON SUNDAY. THE STRONG ARCTIC FRONT WILL BE SOUTH OF THE AREA BY SUNDAY MORNING...WITH STRONG CAA DURING THE DAY. THIS WILL LIMIT THE REBOUNDING OF TEMPS...AND GUIDANCE ONLY HAS HIGHS IN THE TEENS AND 20S. THIS WILL BE 40 TO 50 DEGREES COOLER THAN TODAY. THERE IS THE POSSIBILITY TEMPS MAYBE TWO HIGH...AS FORECAST FOLLOWS GUIDANCE IN WARMING UP AROUND 5 DEGREES DURING THE AFTERNOON. WILL HAVE TO MONITOR AREAS TO THE NORTH TODAY TO SEE IF THERE IS ANY REBOUND OF TEMPS...IT COULD BE A DAY WHERE TEMPS HOLD STEADY OR EVEN FALL DURING THE AFTERNOON. ANOTHER CONCERN WILL BE LIGHT SNOW/FLURRIES. A BAND OF WEAK LIFT FOLLOWS IN THE WAKE OF THE FRONT...ALTHOUGH THE BAND IS IN A DEEP AND FAVORED DENDRITIC GROWTH ZONE. HAVE INCLUDED SOME FLURRIES ACROSS THE AREA...HOWEVER DOWNWIND OF THE BLACK HILLS...COULD SEE SOME LIGHT SNOW ACCUMULATION AND INCLUDED SLIGHT CHANCE POPS. WITH THE WARMING DURING THE DAY...DECIDED TO END THE FLURRIES. A FRONTOGENISIS BAND DEVELOPS SUNDAY EVENING INTO SUNDAY NIGHT AS A MID LEVEL DISTURBANCE CROSS THE CENTRAL ROCKIES. BEST CHANCE FOR SNOW IS ACROSS THE SE PANHANDLE INTO THE SOUTHERN SANDHILLS...WITH GOOD MODEL AGREEMENT OF AT LEAST SOME LIGHT /LESS THAN AN INCH/ ACCUMULATION. MEANWHILE THE SURFACE HIGH NOSES DOWN THE NORTHERN PLAINS. SOME CLEARING IS EXPECTED BY MONDAY MORNING ACROSS THE NORTH...AND TEMPS PLUMMET. LOWS MONDAY MORN ACROSS THE NORTH ARE EXPECTED EITHER SIDE OF 0 DEGREES...WITH SLIGHTLY WARMER TEMPS ACROSS THE SOUTH AS CLOUDS LINGER A LITTLE LONGER. IF ANY AREAS GET AN INCH OF SNOW...TEMPS COULD DROP WELL BELOW ZERO. BY MONDAY AFTERNOON THE HIGH WILL SHIFT OVER SRN MINN/NRN IA. COLD AIR IS SHALLOW AND WILL ALREADY BEGIN TO SEE A REBOUND OF TEMPS FOR MONDAY. STILL COLD WITH MOST AREAS IN THE 20S TO AROUND FREEZING. THE WARM UP CONTINUES FOR TUESDAY WITH 850 TEMPS BACK ABOVE 10 C FOR SW NEB. THIS WILL COMBINE WITH SOME SUN TO PUSH TEMPS ABOVE 50S...STILL IN THE 40S ACROSS THE NORTHEASTERN ZONES. A WEAK PACIFIC FRONT PUSH ACROSS THE AREA TUESDAY NIGHT. A COOL OFF INTO THE 30S AND LOWER 40S IS EXPECTED FOR WEDNESDAY. THE COOL DOWN IS SHORT LIVE AS TEMPS WARM BACK INTO THE 40S AND LOWER 50S FOR THURSDAY AND FRIDAY. AS FOR PRECIP CHANCES...MUCH OF THE WEEK IS DRY. THE MID WEEK PACIFIC FRONT IS FAST MOVING AND LOWER LEVEL MOISTURE IS LIMITED. TOP DOWN SATURATION IS EXPECTED...HOWEVER THE QUICK PACE WILL NOT ALLOW FOR SATURATION TO THE SURFACE...THUS ONLY AN INCREASE OF CLOUDS IS ANTICIPATED AT THIS TIME. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1108 PM CST FRI NOV 28 2014 STRONG WIND ACROSS THE MOUNTAINS IS EXPECTED TO GENERATE 40-55KT WIND 1500-2000 FEET AGL WHICH IS EXPECTED TO STAY DISCONNECTED FROM THE SURFACE UNTIL AFTER 09Z WHEN STRONGER WIND MIXES DOWN TO THE SURFACE. THIS WILL RESULT IN LOW LEVEL WIND SHEAR OF 35-45KT NORTH AND WEST OF AN ANW-TIF-OGA LINE. AFTER 11Z...WIND IN THOSE AREAS WILL INCREASE AND SMOOTH OUT THE LOW LEVEL SHEAR TO 20KT OR LESS. WIND WILL THEN CONTINUE INCREASING TO BECOME 250-290 AT 12-14G21-25KT BY 18Z. WIND WILL DECREASE TO LESS THAN 12KT AND LOSE ITS GUSTINESS BY 01Z. && .FIRE WEATHER... ISSUED AT 400 AM CST SAT NOV 29 2014 ALL OF THE GUIDANCE...THE NAMDNG...HRRR...MOSGUIDE AND THE RAP SHOW STRONG WIND GUST POTENTIAL TODAY ACROSS THE NORTH. THE NAM SHOWS WIND GUSTS TO 35 KT AT KVTN. AT 08Z...KLNX RADAR SHOWS 40 KT WEST WINDS AT 1000 FT AGL. A BLEND OF WIND GUST CLIMO AND THE NAM MODEL PRODUCES WIND GUSTS TO 35 MPH ACROSS THE NORTH. A BLEND OF THE VERY DRY RAP DEWPOINTS AND THE OTHER MODELS PRODUCES DEWPOINTS AROUND 20F ACROSS THE SANDHILLS THIS AFTN WITH MAX TEMPS NEAR 70. RED FLAG CONDITIONS ARE EXPECTED TO DEVELOP THIS AFTERNOON ACROSS THE CENTRAL SANDHILLS. && .CLIMATE... ISSUED AT 400 AM CST SAT NOV 29 2014 NORTH PLATTE SET A NEW RECORD YESTERDAY WITH A HIGH OF 73...AND IMPERIAL TIED IT WITH A HIGH OF 74. TODAY RECORDS ARE 71 /1932/ AT NORTH PLATTE...75 /1901/ AT IMPERIAL...69 /1998 AND 1932/ AT BROKEN BOW...AND 74 /1932/ AT VALENTINE. THE VALENTINE RECORD APPEARS SAFE...HOWEVER THE OTHERS ARE IN JEOPARDY. && .LBF WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM NOON TODAY TO 6 PM CST THIS EVENING FOR NEZ206. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...SPRINGER FIRE WEATHER...CDC CLIMATE...MASEK
AREA FORECAST DISCUSSION
NWS BUFFALO NY
940 PM EST SUN NOV 30 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE REGION OVERNIGHT WITH RAIN SHOWERS ACROSS WESTERN AND NORTH-CENTRAL NEW YORK FOLLOWED BY MUCH COOLER TEMPERATURES MONDAY. TEMPERATURES WILL WARM BACK TOWARDS AVERAGE BY MIDWEEK AS A WARM FRONT LIFTS NORTH...BRINGING WITH IT A CHANCE FOR FREEZING RAIN TUESDAY NIGHT. THE SEE SAW CONTINUES WEDNESDAY AS ANOTHER COLD FRONT SWINGS ACROSS THE AREA...BRINGING ANOTHER ROUND OF COOL BUT MAINLY DRY WEATHER THAT WILL LAST THROUGH THE REMAINDER OF THE WORK WEEK. && .NEAR TERM /THROUGH MONDAY/... A COLD FRONT EXTENDS FROM THE SAINT LAWRENCE VALLEY SOUTHWEST TO BUFFALO THEN ON TO CLEVELAND LATE THIS EVENING. REGIONAL RADARS NOW SHOWING A BAND OF RAIN SHOWERS JUST AHEAD OF THE FRONT WHICH EXTEND FROM WATERTOWN ACROSS LAKE ONTARIO TO BUFFALO TO THEN WEST TO CLEVELAND. THE FRONTS PARALLEL ORIENTATION WITH THE 500MB FLOW WILL KEEP A SLOW MOVEMENT EAST ACROSS THE REGION OVERNIGHT. THE EARLIER BLEND OF QPF FROM THE HRRR AND LOCAL WRF RUNS SEEMS TO BE WORKING OUT VERY WELL SO NO SIGNIFICANT CHANCES WITH THE LATEST UPDATE. STILL EXPECT THE FRONT TO EASE EAST TO A ROCHESTER-JAMESTOWN LINE BY MIDNIGHT THEN THEN TO EASTERN NEW YORK BY 12Z. THE QPF BLEND YIELDS 0.10-0.25 INCH OF RAINFALL. WARM TEMPERATURES CONTINUE TO RANGE THROUGH THE 50S TO AROUND 60 LATE THIS EVENING AHEAD OF THE FRONT. TEMPS WILL DROP BEHIND THE FRONT AS COLD ADVECTION TAKES HOLD...HAVE ADJUSTED TEMP TRENDS TO BE MORE IN LINE WITH RGEM. THERE IS A LOW CHANCE OF SOME RAIN/SNOW MIX ON THE BACK EDGE BUT FOR THE MOST PART IT LOOKS LIKE ALL THE SHOWERS ARE OVER WITH BY THE TIME TEMPS COOL ENOUGH FOR ANY SNOW TO MIX IN. READINGS ACROSS WESTERN NEW YORK WILL FALL INTO THE MID 30S BY DAYBREAK WITH LOWER 40S ACROSS THE EASTERN HALF OF THE FORECAST AREA. COLD AND DRY AIR WILL CONTINUE TO POUR ACROSS THE LOWER GREAT LAKES ON MONDAY WITH EARLY MORNING HIGHS FALLING INTO THE UPPER 20S TO MID 30S...WITH COOLEST READINGS ACROSS HIGHER TERRAIN...BY LATE IN THE DAY. THE DRY ARCTIC AIRMASS WILL PRECLUDE THE DEVELOPMENT OF ANY SIGNIFICANT LAKE EFFECT PRECIPITATION ACROSS THE FORECAST AREA...THOUGH LAKE-EFFECT CLOUDS WILL BE IN ABUNDANCE ALONG WITH PERHAPS A FEW FLURRIES ACROSS UPSLOPE AREAS DOWNWIND OF BOTH LAKES. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... MONDAY NIGHT A SURFACE RIDGE OF HIGH PRESSURE WILL BE ADVANCING FROM THE WESTERN GREAT LAKES TOWARDS SOUTHERN QUEBEC BY TUESDAY MORNING. THIS FEATURE WILL BE RESPONSIBLE FOR DRIER AIR FLOWING ACROSS THE EASTERN GREAT LAKES MONDAY NIGHT...AS WELL AS VEERING WINDS FROM NORTHWEST TO NORTHEAST. A FEW LAKE EFFECT FLURRIES WITHIN THE DRYING ATMOSPHERE EARLY MONDAY NIGHT WILL DISSIPATE ALONG THE INLAND SOUTHERN SHORELINE THROUGH THE EVENING HOURS. OTHERWISE CLEARING SKIES COUPLED WITH A FRESH COLD AIRMASS ASSOCIATED WITH THIS HIGH PRESSURE WILL BRING LOWS IN THE TEENS...TO SINGLE DIGITS ACROSS THE NORTH COUNTRY. TUESDAY EXPECT A COLD START TO THE DAY WITH MORNING SUNSHINE FADING BEHIND THICKENING CIRRUS THAT WILL BE APPROACHING FROM THE SOUTH. MODELS ARE A LITTLE QUICKER WITH THE RETURN FLOW OF MOISTURE BEHIND THIS AREA OF HIGH PRESSURE. THIS WILL LIMIT THE EARLY EVENING COOLING SOME AND LIKELY CONFINE THE FREEZING RAIN POTENTIAL TO MORE OF THE HILLS OF SW NYS AND THE NORTH COUNTRY. PRECIPITATION IS EXPECTED TO ARRIVE ALONG THE LEADING EDGE OF A 55 KNOT LLJ LATER TUESDAY NIGHT AFTER THE DRY BOUNDARY LAYER SATURATES. BY WEDNESDAY MIDDAY SUFFICIENT WARMING ALOFT SHOULD ALLOW FOR JUST PLAIN RAIN SHOWERS TO PASS ACROSS THE REGION...WITH CHANCES LESSENING TOWARDS THE WEST AS A COLD FRONT SENDS THE MAIN SURGE OF MOISTURE EASTWARD OVER EASTERN NEW YORK STATE. WEDNESDAY NIGHT BEHIND THE COLD FRONT LAKE PARAMETERS WILL INCREASE TO SUPPORT LAKE EFFECT SNOW ON A WESTERLY FLOW. WHILE FLURRIES MAY FLY ACROSS SW NYS...THE WESTERLY FLOW ALONG THE LONG LAKE ONTARIO AXIS WITH A FAIR CAPPING INVERSION OF 5K FEET MAY ALLOW FOR MINOR LAKE EFFECT SNOW ACCUMULATIONS ON THE TUG HILL. BEHIND THE COLD FRONT WEDNESDAY NIGHT TEMPERATURES WILL DROP BACK INTO THE 20S...BUT WITH A ZONAL FLOW ALOFT...AND ARCTIC AIR LACKING A SIGNIFICANT DROP IN TEMPERATURES IS NOT LIKELY. && .LONG TERM /THURSDAY THROUGH SUNDAY/... THURSDAY A VIGOROUS SHORTWAVE WILL BE ADVANCING ACROSS SOUTHERN CANADA...BUT SHOULD REMAIN FAR ENOUGH NORTH TO ALLOW FOR A DRY DAY SOUTH OF LAKE ONTARIO...AND JUST SLIGHT CHANCE POPS ACROSS THE SAINT LAWRENCE VALLEY FOR A FEW PASSING SNOW SHOWERS. ALSO SE OF LAKE ONTARIO FLURRIES AND LIGHT LAKE EFFECT SNOW SHOWERS MAY STILL BE FALLING AT THE START OF THE DAY...BUT AS DRIER AIR FILTERS INTO THE LAKE EFFECT ACTIVITY...ALL SNOW SHOWERS SHOULD END THROUGH THE EARLY PART OF THE DAY. BEHIND THIS SHORTWAVE...A ZONAL FLOW WILL DOMINATE WITH TEMPERATURES AVERAGING AROUND NORMAL. A SHORTWAVE WITHIN THIS ZONAL FLOW MAY BRING A MIXTURE OF RAIN/SNOW LATER FRIDAY NIGHT AND SATURDAY...THOUGH WITH MODEL DIFFERENCES (GFS MUCH SLOWER WITH THE SHORTWAVE AND PRECIPITATION) WILL JUST CONTINUE WITH LOW CHANCE/SLIGHT CHANCE POPS FOR NEXT WEEKEND. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... A MIX OF LOW VFR/MVFR CIGS ARE PRESENT THIS EVENING AHEAD OF A COLD FRONT THAT WILL CROSS THE REGION OVERNIGHT. RADAR IS SHOWING A BAND OF RAIN SHOWERS EXTENDING ALONG THE FRONT FROM KART TO KBUF TO KCLE NEAR 03Z. EXPECT RAIN SHOWERS TO BRING SOME LOWERING OF CIGS ALTHOUGH CONFIDENCE FOR IFR IS LOW. KBUF RADAR WIND PROFILE SHOWS A 40-50 KNOT 2KFT JET IN PLACE AHEAD OF THE FRONT SO SOME LLWS HAS BEEN INCLUDED UNTIL RAIN SHOWERS PASS. SOUTHWESTERLY FLOW AHEAD OF THE FRONT WILL VEER WESTERLY BEHIND THE FRONT WITH NOMINAL IMPROVEMENT TO VFR...WITH MVFR ACROSS HIGHER ELEVATIONS...MAINLY AFTER 12Z MON. A SLIGHT CHANCE OF SOME WEAK LAKE EFFECT SNOW IS POSSIBLE SOUTHEAST OF THE LAKES DURING THE DAY MONDAY. CIGS BECOME ALL VFR BY MONDAY EVENING AS HIGH PRESSURE NOSES ACROSS THE LOWER GREAT LAKES. OUTLOOK... MONDAY NIGHT THROUGH TUESDAY...VFR. WEDNESDAY...MAINLY VFR WITH A CHANCE OF SHOWERS. THURSDAY...VFR/MVFR. && .MARINE... BRISK SOUTH-SOUTHWESTERLY WINDS WILL GIVE WAY TO WEST-NORTHWEST FLOW AS A COLD FRONT CROSSES THE LOWER GREAT LAKES OVERNIGHT. INCREASING FETCH AND COLD ADVECTION WILL ALLOW WAVES TO BUILD ON LAKE ONTARIO TONIGHT INTO MONDAY...RESULTING IN WIDESPREAD SMALL CRAFT ADVISORIES ON THAT LAKE WHILE ON LAKE ERIE THE SHORTER FETCH NORTHWESTERLY FLOW SHOULD KEEP WINDS/WAVES JUST UNDER SCA CRITERIA. WAVES WILL BUILD INTO THE 5 TO 7 FOOT RANGE BY LATE IN THE DAY MONDAY ALONG THE SOUTH SHORE OF LAKE ONTARIO BEFORE DIMINISHING LATER MONDAY NIGHT AS HIGH PRESSURE MOVES OVERHEAD. A BRIEF PERIOD OF SMALL CRAFT CONDITIONS WILL RETURN WEDNESDAY AFTERNOON AS ANOTHER COLD FRONT SWEEPS ACROSS THE LAKE FOLLOWED BY ANOTHER HIGH THURSDAY. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST MONDAY FOR LEZ040-041. SMALL CRAFT ADVISORY UNTIL 7 AM EST TUESDAY FOR LOZ043-044. SMALL CRAFT ADVISORY FROM 1 AM MONDAY TO 4 AM EST TUESDAY FOR LOZ042. SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR LOZ045. && $$ SYNOPSIS...SMITH/WOOD NEAR TERM...SMITH/WOOD SHORT TERM...THOMAS LONG TERM...THOMAS AVIATION...SMITH/WOOD MARINE...SMITH/WOOD
AREA FORECAST DISCUSSION
NWS BUFFALO NY
646 PM EST SUN NOV 30 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE REGION TONIGHT BRINGING SHOWERS TO WESTERN AND NORTH-CENTRAL NEW YORK FOLLOWED BY MUCH COOLER TEMPERATURES MONDAY. TEMPERATURES WILL MODERATE TOWARDS AVERAGE BY MIDWEEK AS A WARM FRONT LIFTS NORTH...BRINGING WITH IT A CHANCE FOR FREEZING RAIN TUESDAY NIGHT. THE SEE SAW CONTINUES WEDNESDAY AS ANOTHER COLD FRONT SWINGS ACROSS THE AREA...BRINGING ANOTHER ROUND OF COOL BUT MAINLY DRY WEATHER THAT WILL LAST THROUGH THE REMAINDER OF THE WORK WEEK. && .NEAR TERM /THROUGH MONDAY/... A COLD FRONT EXTENDS FROM THE OTTAWA VALLEY JUST WEST OF BUFFALO TO THE WEST END OF LAKE ERIE THIS EVENING. REGIONAL RADARS NOW SHOWING A BAND OF RAIN SHOWERS JUST AHEAD OF THE FRONT WHICH EXTEND FROM NEAR WATERTOWN ACROSS LAKE ONTARIO TO BUFFALO TO THEN WEST TO TOLEDO. THIS FRONT WILL SLOWLY PUSH EAST ACROSS THE REGION OVERNIGHT AS ITS ORIENTATION IS PARALLEL WITH THE 500MB FLOW. UPDATED THE FORECAST WITH A BLEND OF CURRENT HRRR AND LOCAL WRF RUNS WHICH SHIFTS THE FRONT EAST TO ROCHESTER AND JAMESTOWN BY MIDNIGHT THEN THEN EAST OF THE FORECAST AREA BY 12Z. THE QPF BLEND YIELDED 0.10-0.25 INCH OF RAINFALL. THE WARM TEMPERATURES RANGING THROUGH THE 50S THE EVENING AHEAD OF THE FRONT WILL DROP WITH THE ONSET OF RAIN SHOWERS AND CONTINUE TO DROP BEHIND THE FRONT AS COLD ADVECTION TAKES HOLD. THERE IS A LOW CHANCE OF SOME RAIN/SNOW MIX ON THE BACK EDGE BUT FOR THE MOST PART IT LOOKS LIKE ALL THE SHOWERS ARE OVER WITH BY THE TIME TEMPS COOL ENOUGH FOR ANY SNOW TO MIX IN. READINGS ACROSS WESTERN NEW YORK WILL FALL INTO THE MID 30S BY DAYBREAK WITH LOWER 40S ACROSS THE EASTERN HALF OF THE FORECAST AREA. COLD AND DRY AIR WILL CONTINUE TO POUR ACROSS THE LOWER GREAT LAKES ON MONDAY WITH EARLY MORNING HIGHS FALLING INTO THE UPPER 20S TO MID 30S...WITH COOLEST READINGS ACROSS HIGHER TERRAIN...BY LATE IN THE DAY. THE DRY ARCTIC AIRMASS WILL PRECLUDE THE DEVELOPMENT OF ANY SIGNIFICANT LAKE EFFECT PRECIPITATION ACROSS THE FORECAST AREA...THOUGH LAKE-EFFECT CLOUDS WILL BE IN ABUNDANCE ALONG WITH PERHAPS A FEW FLURRIES ACROSS UPSLOPE AREAS DOWNWIND OF BOTH LAKES. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... MONDAY NIGHT A SURFACE RIDGE OF HIGH PRESSURE WILL BE ADVANCING FROM THE WESTERN GREAT LAKES TOWARDS SOUTHERN QUEBEC BY TUESDAY MORNING. THIS FEATURE WILL BE RESPONSIBLE FOR DRIER AIR FLOWING ACROSS THE EASTERN GREAT LAKES MONDAY NIGHT...AS WELL AS VEERING WINDS FROM NORTHWEST TO NORTHEAST. A FEW LAKE EFFECT FLURRIES WITHIN THE DRYING ATMOSPHERE EARLY MONDAY NIGHT WILL DISSIPATE ALONG THE INLAND SOUTHERN SHORELINE THROUGH THE EVENING HOURS. OTHERWISE CLEARING SKIES COUPLED WITH A FRESH COLD AIRMASS ASSOCIATED WITH THIS HIGH PRESSURE WILL BRING LOWS IN THE TEENS...TO SINGLE DIGITS ACROSS THE NORTH COUNTRY. TUESDAY EXPECT A COLD START TO THE DAY WITH MORNING SUNSHINE FADING BEHIND THICKENING CIRRUS THAT WILL BE APPROACHING FROM THE SOUTH. MODELS ARE A LITTLE QUICKER WITH THE RETURN FLOW OF MOISTURE BEHIND THIS AREA OF HIGH PRESSURE. THIS WILL LIMIT THE EARLY EVENING COOLING SOME AND LIKELY CONFINE THE FREEZING RAIN POTENTIAL TO MORE OF THE HILLS OF SW NYS AND THE NORTH COUNTRY. PRECIPITATION IS EXPECTED TO ARRIVE ALONG THE LEADING EDGE OF A 55 KNOT LLJ LATER TUESDAY NIGHT AFTER THE DRY BOUNDARY LAYER SATURATES. BY WEDNESDAY MIDDAY SUFFICIENT WARMING ALOFT SHOULD ALLOW FOR JUST PLAIN RAIN SHOWERS TO PASS ACROSS THE REGION...WITH CHANCES LESSENING TOWARDS THE WEST AS A COLD FRONT SENDS THE MAIN SURGE OF MOISTURE EASTWARD OVER EASTERN NEW YORK STATE. WEDNESDAY NIGHT BEHIND THE COLD FRONT LAKE PARAMETERS WILL INCREASE TO SUPPORT LAKE EFFECT SNOW ON A WESTERLY FLOW. WHILE FLURRIES MAY FLY ACROSS SW NYS...THE WESTERLY FLOW ALONG THE LONG LAKE ONTARIO AXIS WITH A FAIR CAPPING INVERSION OF 5K FEET MAY ALLOW FOR MINOR LAKE EFFECT SNOW ACCUMULATIONS ON THE TUG HILL. BEHIND THE COLD FRONT WEDNESDAY NIGHT TEMPERATURES WILL DROP BACK INTO THE 20S...BUT WITH A ZONAL FLOW ALOFT...AND ARCTIC AIR LACKING A SIGNIFICANT DROP IN TEMPERATURES IS NOT LIKELY. && .LONG TERM /THURSDAY THROUGH SUNDAY/... THURSDAY A VIGOROUS SHORTWAVE WILL BE ADVANCING ACROSS SOUTHERN CANADA...BUT SHOULD REMAIN FAR ENOUGH NORTH TO ALLOW FOR A DRY DAY SOUTH OF LAKE ONTARIO...AND JUST SLIGHT CHANCE POPS ACROSS THE SAINT LAWRENCE VALLEY FOR A FEW PASSING SNOW SHOWERS. ALSO SE OF LAKE ONTARIO FLURRIES AND LIGHT LAKE EFFECT SNOW SHOWERS MAY STILL BE FALLING AT THE START OF THE DAY...BUT AS DRIER AIR FILTERS INTO THE LAKE EFFECT ACTIVITY...ALL SNOW SHOWERS SHOULD END THROUGH THE EARLY PART OF THE DAY. BEHIND THIS SHORTWAVE...A ZONAL FLOW WILL DOMINATE WITH TEMPERATURES AVERAGING AROUND NORMAL. A SHORTWAVE WITHIN THIS ZONAL FLOW MAY BRING A MIXTURE OF RAIN/SNOW LATER FRIDAY NIGHT AND SATURDAY...THOUGH WITH MODEL DIFFERENCES (GFS MUCH SLOWER WITH THE SHORTWAVE AND PRECIPITATION) WILL JUST CONTINUE WITH LOW CHANCE/SLIGHT CHANCE POPS FOR NEXT WEEKEND. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... A MIX OF LOW VFR/MVFR CIGS ARE PRESENT THIS EVENING AHEAD OF A COLD FRONT THAT WILL CROSS THE REGION. THIS FRONT WILL BRING A PERIOD OF RAIN SHOWERS WITH SOME LOWERING OF CIGS ALTHOUGH CONFIDENCE FOR IFR IS LOW. KBUF RADAR WIND PROFILE SHOWS A 40-50 KNOT 2KFT JET IN PLACE AHEAD OF THE FRONT SO SOME LLWS HAS BEEN INCLUDED UNTIL RAIN SHOWERS ARRIVE. SOUTHWESTERLY FLOW AHEAD OF THE FRONT WILL VEER WESTERLY BEHIND THE FRONT WITH NOMINAL IMPROVEMENT TO VFR...WITH MVFR ACROSS HIGHER ELEVATIONS...MAINLY AFTER 12Z MON. A SLIGHT CHANCE OF SOME WEAK LAKE EFFECT SNOW IS POSSIBLE SOUTHEAST OF THE LAKES DURING THE DAY MONDAY. CIGS BECOME ALL VFR BY MONDAY EVENING AS HIGH PRESSURE NOSES ACROSS THE LOWER GREAT LAKES. OUTLOOK... MONDAY NIGHT THROUGH TUESDAY...VFR. WEDNESDAY...MAINLY VFR WITH A CHANCE OF SHOWERS. THURSDAY...VFR/MVFR. && .MARINE... BRISK SOUTH-SOUTHWESTERLY WINDS WILL GIVE WAY TO WEST-NORTHWEST FLOW AS A COLD FRONT CROSSES THE LOWER GREAT LAKES TONIGHT. INCREASING FETCH AND COLD ADVECTION WILL ALLOW WAVES TO BUILD ON LAKE ONTARIO TONIGHT INTO MONDAY...RESULTING IN WIDESPREAD SMALL CRAFT ADVISORIES ON THAT LAKE WHILE ON LAKE ERIE THE SHORTER FETCH NORTHWESTERLY FLOW SHOULD KEEP WINDS/WAVES JUST UNDER SCA CRITERIA. WAVES WILL BUILD INTO THE 5 TO 7 FOOT RANGE BY LATE IN THE DAY MONDAY ALONG THE SOUTH SHORE OF LAKE ONTARIO BEFORE DIMINISHING LATER MONDAY NIGHT AS HIGH PRESSURE MOVES OVERHEAD. A BRIEF PERIOD OF SMALL CRAFT CONDITIONS WILL RETURN WEDNESDAY AFTERNOON AS ANOTHER COLD FRONT SWEEPS ACROSS THE LAKE FOLLOWED BY ANOTHER HIGH THURSDAY. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST MONDAY FOR LEZ040-041. SMALL CRAFT ADVISORY UNTIL 7 AM EST TUESDAY FOR LOZ043-044. SMALL CRAFT ADVISORY FROM 1 AM MONDAY TO 4 AM EST TUESDAY FOR LOZ042. SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR LOZ045. && $$ SYNOPSIS...WOOD NEAR TERM...SMITH/WOOD SHORT TERM...THOMAS LONG TERM...THOMAS AVIATION...SMITH/WOOD MARINE...SMITH/WOOD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
945 PM CST SUN NOV 30 2014 .UPDATE... ISSUED AT 945 PM CST SUN NOV 30 2014 FORECAST CHALLENGE FOR TONIGHT WILL BE TEMPERATURES. THE BIAS CORRECTED NAM12 00Z RUN VERIFIED WITH 03Z OBS BETTER THAN OTHER MODELS...WITH MOST MODELS IN THE BALL PARK BUT THE HRRR A BIT WARMER AND GFS SIGNIFICANTLY WARMER. THEREFORE WILL BUILD NOCTURNAL CURVE FROM NAM GUIDANCE...WHICH ENDS UP BEING A BIT WARMER IN THE FAR EAST AND COLDER IN THE NORTHWEST. MAIN IMPACT ON HEADLINES IS IT BRINGS THE SOUTHERN TIER OF COUNTIES INTO WIND CHILL ADVISORY CRITERIA A FEW HOURS LATER...BUT WILL KEEP HEADLINES AS THEY ARE EXPECTING A QUICK DROP ONCE THE WINDS LET UP SOME. TOMORROW MORNING...LANGDON AREA COULD MAKE IT INTO THE 40S BELOW (WIND CHILL) BUT NOT WIDESPREAD ENOUGH TO WARRANT UPGRADING SUCH A SMALL AREA TO WIND CHILL WARNING. UPDATE ISSUED AT 658 PM CST SUN NOV 30 2014 SURFACE HIGH IS CURRENTLY OVER EASTERN MT...WITH WEST SOUTHWEST WINDS ACROSS NORTH DAKOTA. TEMPERATURES ACROSS THE NORTH HAVE DROPPED A FEW DEGREES BELOW FREEZING AND WITH THE BREEZY WINDS...WIND CHILLS HAVE FALLEN TO 25 TO 30 BELOW ZERO IN PORTIONS OF EASTERN NORTH DAKOTA. TIMING OF CURRENT HEADLINES IS IN GOOD SHAPE AND NO CHANGES PLANNED TO ONGOING FORECAST OR HEADLINES. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 300 PM CST SUN NOV 30 2014 MAIN CHALLENGES WILL BE WINDS AND TEMPS AND THE RESULTING WIND CHILL READINGS. AS OF MID AFTERNOON SKIES HAD COMPLETELY CLEARED OUT WITH GUSTY WEST WINDS. DESPITE HAVING A LITTLE SNOW ON THE GROUND...THE WEST WINDS AND SUN HAVE ALLOWED TEMPS TO RISE ABOVE ZERO JUST ABOUT EVERYWHERE. STILL EXPECTING THE WAVE NEARING THE MANITOBA LAKES REGION TO SWING THRU THE AREA TONIGHT...BUT NOT SEEING ANY CLOUDS ASSOCIATED WITH IT. THEREFORE WILL STICK WITH A CLEAR FORECAST. THERE ARE SOME COLDER TEMPS ASSOCIATED WITH THE WAVE WHICH WILL CAUSE STEADY COLD ADVECTION THRU THE EVENING. THIS SHOULD RESULT IN STEADY WEST TO NW WINDS AT LEAST THRU MIDNIGHT...AND POSSIBLY EVEN BEYOND. THINK AS THE SFC HIGH BUILDS INTO SOUTHEAST ND TOWARD 12Z MON WINDS WILL FINALLY DROP OFF. THIS WILL PROBABLY ALLOW A RAPID TEMP FALL SO WILL STICK WITH LOWS TONIGHT IN THE 15 TO 20 BELOW ZERO RANGE. ALREADY ISSUED A WIND CHILL ADVISORY FOR THE ENTIRE FA UNTIL MID TO LATE MON MORNING. ONE ISSUE TO CONSIDER IS REACHING WIND CHILL WARNING CRITERIA OR WIND CHILL READINGS 40F BELOW OR COLDER. CURRENT FORECAST SHOWS THE NORTHWEST FA GETTING CLOSE BUT WITH UNCERTAINTIES IN HOW FAST WINDS WILL DROP OFF AND THE RESULTING TEMPS THINK AN ADVISORY IS GOOD FOR NOW. EXPECT LOTS OF SUN AGAIN ON MONDAY WITH WINDS TURNING AROUND TO THE SOUTH. BY AFTERNOON INTO MON EVENING PRETTY GUSTY SOUTH WINDS EXPECTED. COMBINATION OF WINDS AND WARM ADVECTION WILL KEEP TEMPS WARMER MON NIGHT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 300 PM CST SUN NOV 30 2014 MODELS HAD BEEN SHOWING A WEAK BAND OF LIGHT SNOW MOVING ALONG THE ND/SD BORDER ON TUE/TUE NIGHT. GFS/ECMWF HAVE BACKED OFF ON THIS WHILE NAM/GEM KEEP SOME SEMBLANCES OF IT AROUND. WITH THE UNCERTAINTY NOW WILL GO WITH A DRY FORECAST. MODELS ALSO HAVE A LITTLE LIGHT SNOW DROPPING TOWARD THE NORTHEAST FA 12Z-18Z WED. FOR NOW KEPT IT DRY TOO AND WILL SEE WHAT LATER RUNS BRING. WEDNESDAY NIGHT-SUNDAY...MODELS IN DECENT AGREEMENT WITH OVERALL TRENDS. NORTHWEST FLOW ALOFT WILL TRANSITION TO ZONAL FLOW THROUGH THIS PERIOD. NO STRONG SIGNALS FOR PRECIPITATION FROM ANY MODEL...AND HAVE GONE WITH A DRY FORECAST. WITH THAT SAID...THERE COULD BE A LOW PREDICTIVE EVENT...BUT THESE TYPES OF EVENTS USUALLY HAVE MINIMAL IMPACT. TEMPERATURE WILL BE THE MAIN CHALLENGE...LIKELY TRANSITIONING TO ABOVE NORMAL VALUES BY THE WEEKEND (AND WITH MINIMAL SNOW COVER THE QUESTION WILL BE HOW WARM FOR MAX TEMPS). && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 658 PM CST SUN NOV 30 2014 SURFACE HIGH OVER EASTERN MT WILL SHIFT OVER SOUTHERN VALLEY TONIGHT...AND NW WINDS WILL BECOME W THEN S OVER THE NEXT 24 HRS. CLEAR SKIES EXPECTED AS A COLD AND DRY ARCTIC AIRMASS MOVES INTO THE AREA. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR NDZ038-039-049- 052-053. WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR NDZ006>008-014>016- 024-026>030-054. MN...WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR MNZ003-024- 027>032-040. WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR MNZ001-002-004>009- 013>017-022-023. && $$ UPDATE...SPEICHER SHORT TERM...GODON LONG TERM...GODON/TG AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1210 PM CST SAT NOV 29 2014 .UPDATE... ISSUED AT 1209 AM CST SAT NOV 29 2014 MADE ADJUSTMENTS TO POPS BASED ON BAND OF SNOW CURRENTLY IN NORTHEASTERN MONTANA AND EXTENDING INTO NORTHWEST ND. SOME HEAVY SNOW REPORTED UNDER THE BAND AND RAP/HRRR SEEM TO HAVE INITIALIZED IT WELL. THE EXPECTATION IS FOR THE BAND TO DIMINISH...HOWEVER HAVE UPPED POPS ACROSS THE NORTHWEST AND SNOW AMOUNTS SLIGHTLY FOR WILLIAMS AND DIVIDE WITH AN INCH OR TWO OF SNOW POSSIBLE. ALSO MADE ADJUSTMENTS TO POPS THROUGH THIS EVENING INCORPORATING LATEST SHORT TERM MODEL GUIDANCE WITH SOME ADDITIONAL TWEAKS...MAINLY TO ADD LOW POPS IN SOME AREAS. UPDATE ISSUED AT 906 AM CST SAT NOV 29 2014 COLD FRONT HAS PASSED MAJORITY OF CWA AND JUST ABOUT THROUGH THE EXTREME SOUTHEAST. FOR THIS UPDATE...FORECAST HOURLY TEMPS WERE RUNNING SLIGHTLY HIGH SO ADJUSTED TO CURRENT OBSERVED TEMPS. TEMPS AT 15Z RANGED FROM NEAR ZERO EXTREME NORTHWEST TO THE UPPER TEENS SOUTH. RADAR IS NOT SHOWING MUCH PRECIP BUT A FEW SURFACE OBS AND WEB CAMS WERE SHOWING LIGHT SNOW ACROSS THE SOUTHWEST (BEACH AND DICKINSON) AND ALSO NORTH. THEREFORE EXPANDED POPS TO COVER THESE AREAS. PRECIP TYPE APPEARS TO BE ALL SNOW. GLASGOW RADAR SHOWS AREA OF PRECIP APPROACHING NORTHEAST MONTANA AND SHOULD SPREAD INTO WESTERN NORTH DAKOTA WITHIN NEXT FEW HOURS. WILL MONITOR TRENDS AND LATEST GUIDANCE AND TWEAK POPS AS NEEDED WITH ADDITIONAL UPDATES. UPDATE ISSUED AT 650 AM CST SAT NOV 29 2014 LEADING EDGE OF COLDER AIR NOW PASSING THROUGH CENTRAL NORTH DAKOTA WITH EXTENSIVE LOW CLOUDS...SOME POCKETS OF MIXED PRECIPITATION AND PATCHY FOG. WINDS BEHIND THE FRONT WERE GUSTING TO 25 MPH FROM THE NORTHWEST. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 400 AM CST SAT NOV 29 2014 FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE PRECIPITATION CHANCES THROUGH THE PERIOD AND VERY COLD AIR PUSHING SOUTH ACROSS THE REGION TODAY INTO TONIGHT. CURRENTLY...QUASI-ZONAL FLOW ALOFT OVER THE NORTHERN PLAINS THIS MORNING AS A BROAD UPPER LEVEL RIDGE CONTINUES TO BE FLATTENED BY A VIGOROUS UPPER LEVEL S/WV TROUGH MOVING INTO THE PACIFIC NORTHWEST. EMBEDDED MID LEVEL IMPULSES CONTINUE TO STREAM EAST ACROSS THE REGION WITHIN THE FLOW. LATEST HIGH RESOLUTION MODELS OF THE HRRR AND RAP INDICATE A CONTINUED CHANCE FOR LIGHT PRECIPITATION ACROSS THE NORTH THROUGH SATURDAY MORNING AS THE MID LEVEL IMPULSES INTERACT WITH A COLD FRONTAL FRONTAL BOUNDARY NOW MOVING SOUTHWARD ACROSS THE STATE. IMPULSE NOW OVER NORTHEASTERN MONTANA WILL PUSH THROUGH MY FAR NORTHWEST/NORTH CENTRAL BETWEEN NOW AND 13-15Z. MAINTAINED ELEVATED POPS FOR THIS FEATURE NEAR THE CANADIAN BORDER...TRIMMED FARTHER SOUTH WITH LATEST HR GUIDANCE TRENDING MORE NORTH. PRECIP TYPE SHOULD MAINLY BE SNOW BUT WILL STILL HAVE A SLIGHT CHANCE OF A SLEET/FREEZING RAIN MIX ALONG TO SOUTH OF THE ZERO DEGREE ISOTHERM ALOFT. NEXT WAVE OF PRECIPITATION ARRIVES LATER THIS MORNING INTO THE AFTERNOON WHEN ANOTHER MID LEVEL WAVE MOVING EAST THROUGH THE REGION MOVES OVER A SECONDARY COLD FRONT. LEANED AWAY FROM THE ECMWF WITH ITS FARTHER NORTH PLACEMENT OF QPF WITH ALL OTHER GUIDANCE MORE SOUTH WITH THE PRECIPITATION AXIS STARTING IN WEST- CENTRAL ND AND EXPANDING EASTWARD...WITH PRECIP CHANCES DEVELOPING SOUTH TODAY WITH TIME ALONG THE FROPA. MAINLY SNOW EXPECTED WITH TEMPS ALOFT SUBFREEZING BY THE ONSET OF PRECIPITATION OR VERY SHORTLY AFTER. AN INCH OF SNOW ACCUMULATION POSSIBLE BUT MOST LOCATIONS SHOULD REMAIN LESS THAN AN INCH AND CLOSER TO A FEW TENTHS. CHANCES FOR LIGHT SNOW PUSH SOUTH WITH TIME AND WILL END OVERNIGHT. GUSTY NORTHWEST WINDS ALREADY DEVELOPING ACROSS MY NORTHWEST BEHIND THE COLD FRONT WILL EXPAND SOUTH AND EAST. WITH CAA ONGOING THROUGH TODAY AND TONIGHT...DO NOT SEE THE WINDS TAPERING OFF MUCH THIS EVENING UNTIL AFTER MIDNIGHT WHEN PRESSURE RISES SUBSIDE. HIGHS FOR TODAY LIKELY ALREADY REACHED EARLY THIS MORNING WITH FALLING TEMPERATURES EXPECTED TODAY. OVERNIGHT LOWS FROM ZERO SOUTH TO 10 BELOW NORTH WILL COMBINE WITH THE WINDS TO RESULT IN ADVISORY LEVEL WIND CHILL TEMPERATURES SO WILL HOIST A WIND CHILL ADVISORY FOR ALL BUT THE SOUTH CENTRAL WHERE FORECAST WIND CHILLS REMAIN MARGINAL FOR AN ADVISORY. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 400 AM CST SAT NOV 29 2014 THE ONLY CONCERN FOR THE LONG TERM IS THE CONTINUATION OF WIND CHILL HEADLINES THROUGH ABOUT NOON ON MONDAY. AS TEMPERATURES CLIMB INTO THE SINGLE DIGITS ABOVE ZERO DURING THE DAY SUNDAY THE CHILLS WILL MODERATE OUT OF ADVISORY CRITERIA MOST AREAS...BUT VERY TEMPORARILY...AS A BITTERLY COLD SUNDAY NIGHT / MONDAY MORNING FORCE CHILLS BACK INTO THE 20S AND 30S BELOW ZERO NORTH AND EAST OF A LINE FROM WILLISTON THROUGH JAMESTOWN. THOSE OUTSIDE...AND NOT PROPERLY CLOTHED...SUNDAY NIGHT AND MONDAY MORNING WILL BE AT RISK FOR FROST BITE IN ABOUT 20 MINUTES. BECAUSE OF THE ONLY BRIEF PERIOD OUT OF ADVISORY THRESHOLDS...WILL NOT END THE ADVISORY AND KICK IT BACK IN TO EFFECT...RATHER...WILL KEEP IT GOING THROUGH THE DAY SUNDAY...AND RIGHT ON THROUGH MONDAY MORNING. SYNOPTICALLY IN THE LONG TERM...THE CENTER OF THE COLD POOL ALOFT PASSES JUST TO OUR NORTHEAST ON SUNDAY NIGHT WITH SURFACE HIGH PRESSURE NEAR ABERDEEN SOUTH DAKOTA FOR DAYBREAK MONDAY. LOCAL RESEARCH STUDIES SHOW THAT THIS IS A FAVORABLE LOCATION OF THE SURFACE FEATURE TO HAVE THE BOTTOM DROP OUT OF THE THERMOMETER AT BISMARCK. A BREEZY SOUTHWEST SURFACE FLOW SETS UP LATER MONDAY BEHIND THE HIGH AND AHEAD OF A WARM FRONT THAT MEANS BRIEF MODERATION IN TEMPERATURE FOR TUESDAY. TEMPERATURES MONDAY NIGHT COULD ACTUALLY BE RISING THROUGH THE NIGHT...ESPECIALLY SOUTHWEST. ANOTHER PIECE OF THE COLD AIR COMES THROUGH WEDNESDAY BEFORE A PROLONGED SPELL OF WARMER AIR FOR THE END OF THE WEEK AND THE WEEKEND GRACES US AS THE ARCTIC DOME RETREATS FARTHER NORTH INTO CANADA. NOTE THAT THE RECORD LOW AT BISMARCK FOR DECEMBER 1...MONDAY...IS -23 FROM 1893. WE ARE FORECASTING TEENS BELOW FOR ACTUAL AIR TEMPERATURES. SHOULD THAT BOTTOM FALL OUT...AS IS POSSIBLE...THAT WOULD BE A HECK OF A RECORD TO BREAK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1209 AM CST SAT NOV 29 2014 CONDITIONS ARE CURRENTLY MVFR AT MOST LOCATIONS AS THE ARCTIC FRONT HAS PUSHED ACROSS THE REGION WITH GUSTY NORTHWEST WINDS AND MVFR CEILINGS BEHIND THE FRONT. EXPECT MAINLY MVFR TO CONTINUE THROUGH THE DAY WITH A GRADUAL IMPROVEMENT TO VFR TONIGHT FROM NORTH TO SOUTH AS HIGH PRESSURE AND DRYER AIR BEGINS TO FILTER SOUTHWARD. && .BIS WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY FROM 6 PM CST /5 PM MST/ THIS EVENING TO NOON CST /11 AM MST/ SUNDAY FOR NDZ017>019-031>033-040-041-043- 044. WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO NOON CST MONDAY FOR NDZ001>005-009>013-021>023-025-036-037. && $$ UPDATE...JNS SHORT TERM...NH LONG TERM...JPM AVIATION...JNS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
906 AM CST SAT NOV 29 2014 .UPDATE... ISSUED AT 906 AM CST SAT NOV 29 2014 COLD FRONT HAS PASSED MAJORITY OF CWA AND JUST ABOUT THROUGH THE EXTREME SOUTHEAST. FOR THIS UPDATE...FORECAST HOURLY TEMPS WERE RUNNING SLIGHTLY HIGH SO ADJUSTED TO CURRENT OBSERVED TEMPS. TEMPS AT 15Z RANGED FROM NEAR ZERO EXTREME NORTHWEST TO THE UPPER TEENS SOUTH. RADAR IS NOT SHOWING MUCH PRECIP BUT A FEW SURFACE OBS AND WEB CAMS WERE SHOWING LIGHT SNOW ACROSS THE SOUTHWEST (BEACH AND DICKINSON) AND ALSO NORTH. THEREFORE EXPANDED POPS TO COVER THESE AREAS. PRECIP TYPE APPEARS TO BE ALL SNOW. GLASGOW RADAR SHOWS AREA OF PRECIP APPROACHING NORTHEAST MONTANA AND SHOULD SPREAD INTO WESTERN NORTH DAKOTA WITHIN NEXT FEW HOURS. WILL MONITOR TRENDS AND LATEST GUIDANCE AND TWEAK POPS AS NEEDED WITH ADDITIONAL UPDATES. UPDATE ISSUED AT 650 AM CST SAT NOV 29 2014 LEADING EDGE OF COLDER AIR NOW PASSING THROUGH CENTRAL NORTH DAKOTA WITH EXTENSIVE LOW CLOUDS...SOME POCKETS OF MIXED PRECIPITATION AND PATCHY FOG. WINDS BEHIND THE FRONT WERE GUSTING TO 25 MPH FROM THE NORTHWEST. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 400 AM CST SAT NOV 29 2014 FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE PRECIPITATION CHANCES THROUGH THE PERIOD AND VERY COLD AIR PUSHING SOUTH ACROSS THE REGION TODAY INTO TONIGHT. CURRENTLY...QUASI-ZONAL FLOW ALOFT OVER THE NORTHERN PLAINS THIS MORNING AS A BROAD UPPER LEVEL RIDGE CONTINUES TO BE FLATTENED BY A VIGOROUS UPPER LEVEL S/WV TROUGH MOVING INTO THE PACIFIC NORTHWEST. EMBEDDED MID LEVEL IMPULSES CONTINUE TO STREAM EAST ACROSS THE REGION WITHIN THE FLOW. LATEST HIGH RESOLUTION MODELS OF THE HRRR AND RAP INDICATE A CONTINUED CHANCE FOR LIGHT PRECIPITATION ACROSS THE NORTH THROUGH SATURDAY MORNING AS THE MID LEVEL IMPULSES INTERACT WITH A COLD FRONTAL FRONTAL BOUNDARY NOW MOVING SOUTHWARD ACROSS THE STATE. IMPULSE NOW OVER NORTHEASTERN MONTANA WILL PUSH THROUGH MY FAR NORTHWEST/NORTH CENTRAL BETWEEN NOW AND 13-15Z. MAINTAINED ELEVATED POPS FOR THIS FEATURE NEAR THE CANADIAN BORDER...TRIMMED FARTHER SOUTH WITH LATEST HR GUIDANCE TRENDING MORE NORTH. PRECIP TYPE SHOULD MAINLY BE SNOW BUT WILL STILL HAVE A SLIGHT CHANCE OF A SLEET/FREEZING RAIN MIX ALONG TO SOUTH OF THE ZERO DEGREE ISOTHERM ALOFT. NEXT WAVE OF PRECIPITATION ARRIVES LATER THIS MORNING INTO THE AFTERNOON WHEN ANOTHER MID LEVEL WAVE MOVING EAST THROUGH THE REGION MOVES OVER A SECONDARY COLD FRONT. LEANED AWAY FROM THE ECMWF WITH ITS FARTHER NORTH PLACEMENT OF QPF WITH ALL OTHER GUIDANCE MORE SOUTH WITH THE PRECIPITATION AXIS STARTING IN WEST- CENTRAL ND AND EXPANDING EASTWARD...WITH PRECIP CHANCES DEVELOPING SOUTH TODAY WITH TIME ALONG THE FROPA. MAINLY SNOW EXPECTED WITH TEMPS ALOFT SUBFREEZING BY THE ONSET OF PRECIPITATION OR VERY SHORTLY AFTER. AN INCH OF SNOW ACCUMULATION POSSIBLE BUT MOST LOCATIONS SHOULD REMAIN LESS THAN AN INCH AND CLOSER TO A FEW TENTHS. CHANCES FOR LIGHT SNOW PUSH SOUTH WITH TIME AND WILL END OVERNIGHT. GUSTY NORTHWEST WINDS ALREADY DEVELOPING ACROSS MY NORTHWEST BEHIND THE COLD FRONT WILL EXPAND SOUTH AND EAST. WITH CAA ONGOING THROUGH TODAY AND TONIGHT...DO NOT SEE THE WINDS TAPERING OFF MUCH THIS EVENING UNTIL AFTER MIDNIGHT WHEN PRESSURE RISES SUBSIDE. HIGHS FOR TODAY LIKELY ALREADY REACHED EARLY THIS MORNING WITH FALLING TEMPERATURES EXPECTED TODAY. OVERNIGHT LOWS FROM ZERO SOUTH TO 10 BELOW NORTH WILL COMBINE WITH THE WINDS TO RESULT IN ADVISORY LEVEL WIND CHILL TEMPERATURES SO WILL HOIST A WIND CHILL ADVISORY FOR ALL BUT THE SOUTH CENTRAL WHERE FORECAST WIND CHILLS REMAIN MARGINAL FOR AN ADVISORY. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 400 AM CST SAT NOV 29 2014 THE ONLY CONCERN FOR THE LONG TERM IS THE CONTINUATION OF WIND CHILL HEADLINES THROUGH ABOUT NOON ON MONDAY. AS TEMPERATURES CLIMB INTO THE SINGLE DIGITS ABOVE ZERO DURING THE DAY SUNDAY THE CHILLS WILL MODERATE OUT OF ADVISORY CRITERIA MOST AREAS...BUT VERY TEMPORARILY...AS A BITTERLY COLD SUNDAY NIGHT / MONDAY MORNING FORCE CHILLS BACK INTO THE 20S AND 30S BELOW ZERO NORTH AND EAST OF A LINE FROM WILLISTON THROUGH JAMESTOWN. THOSE OUTSIDE...AND NOT PROPERLY CLOTHED...SUNDAY NIGHT AND MONDAY MORNING WILL BE AT RISK FOR FROST BITE IN ABOUT 20 MINUTES. BECAUSE OF THE ONLY BRIEF PERIOD OUT OF ADVISORY THRESHOLDS...WILL NOT END THE ADVISORY AND KICK IT BACK IN TO EFFECT...RATHER...WILL KEEP IT GOING THROUGH THE DAY SUNDAY...AND RIGHT ON THROUGH MONDAY MORNING. SYNOPTICALLY IN THE LONG TERM...THE CENTER OF THE COLD POOL ALOFT PASSES JUST TO OUR NORTHEAST ON SUNDAY NIGHT WITH SURFACE HIGH PRESSURE NEAR ABERDEEN SOUTH DAKOTA FOR DAYBREAK MONDAY. LOCAL RESEARCH STUDIES SHOW THAT THIS IS A FAVORABLE LOCATION OF THE SURFACE FEATURE TO HAVE THE BOTTOM DROP OUT OF THE THERMOMETER AT BISMARCK. A BREEZY SOUTHWEST SURFACE FLOW SETS UP LATER MONDAY BEHIND THE HIGH AND AHEAD OF A WARM FRONT THAT MEANS BRIEF MODERATION IN TEMPERATURE FOR TUESDAY. TEMPERATURES MONDAY NIGHT COULD ACTUALLY BE RISING THROUGH THE NIGHT...ESPECIALLY SOUTHWEST. ANOTHER PIECE OF THE COLD AIR COMES THROUGH WEDNESDAY BEFORE A PROLONGED SPELL OF WARMER AIR FOR THE END OF THE WEEK AND THE WEEKEND GRACES US AS THE ARCTIC DOME RETREATS FARTHER NORTH INTO CANADA. NOTE THAT THE RECORD LOW AT BISMARCK FOR DECEMBER 1...MONDAY...IS -23 FROM 1893. WE ARE FORECASTING TEENS BELOW FOR ACTUAL AIR TEMPERATURES. SHOULD THAT BOTTOM FALL OUT...AS IS POSSIBLE...THAT WOULD BE A HECK OF A RECORD TO BREAK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 650 AM CST SAT NOV 29 2014 MVFR CIGS AT KISN EXPECTED TO IMPROVE BY THIS AFTERNOON. IFR/VLIFR CIGS AT KDIK WILL LIFT TO IFR-MVFR BY 18Z. MVFR CIGS AT KBIS- KMOT-KJMS THIS MORNING. CIGS EXPECTED TO IMPROVE TO VFR LATER TODAY INTO TONIGHT FROM NORTH TO SOUTH AS COLDER / DRIER AIR WORKS IN. UNTIL THEN EXPECT NORTHWEST WIND GUSTS UP TO 30 KNOTS WITH POCKETS OF MIXED PRECIPITATION OF -SN / -FZRA THROUGH 18Z...THEN MAINLY -SN. && .BIS WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY FROM 6 PM CST /5 PM MST/ THIS EVENING TO NOON CST /11 AM MST/ SUNDAY FOR NDZ017>019-031>033-040-041-043- 044. WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO NOON CST MONDAY FOR NDZ001>005-009>013-021>023-025-036-037. && $$ UPDATE...JNS SHORT TERM...NH LONG TERM...JPM AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
652 AM CST SAT NOV 29 2014 .UPDATE... ISSUED AT 650 AM CST SAT NOV 29 2014 LEADING EDGE OF COLDER AIR NOW PASSING THROUGH CENTRAL NORTH DAKOTA WITH EXTENSIVE LOW CLOUDS...SOME POCKETS OF MIXED PRECIPITATION AND PATCHY FOG. WINDS BEHIND THE FRONT WERE GUSTING TO 25 MPH FROM THE NORTHWEST. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 400 AM CST SAT NOV 29 2014 FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE PRECIPITATION CHANCES THROUGH THE PERIOD AND VERY COLD AIR PUSHING SOUTH ACROSS THE REGION TODAY INTO TONIGHT. CURRENTLY...QUASI-ZONAL FLOW ALOFT OVER THE NORTHERN PLAINS THIS MORNING AS A BROAD UPPER LEVEL RIDGE CONTINUES TO BE FLATTENED BY A VIGOROUS UPPER LEVEL S/WV TROUGH MOVING INTO THE PACIFIC NORTHWEST. EMBEDDED MID LEVEL IMPULSES CONTINUE TO STREAM EAST ACROSS THE REGION WITHIN THE FLOW. LATEST HIGH RESOLUTION MODELS OF THE HRRR AND RAP INDICATE A CONTINUED CHANCE FOR LIGHT PRECIPITATION ACROSS THE NORTH THROUGH SATURDAY MORNING AS THE MID LEVEL IMPULSES INTERACT WITH A COLD FRONTAL FRONTAL BOUNDARY NOW MOVING SOUTHWARD ACROSS THE STATE. IMPULSE NOW OVER NORTHEASTERN MONTANA WILL PUSH THROUGH MY FAR NORTHWEST/NORTH CENTRAL BETWEEN NOW AND 13-15Z. MAINTAINED ELEVATED POPS FOR THIS FEATURE NEAR THE CANADIAN BORDER...TRIMMED FARTHER SOUTH WITH LATEST HR GUIDANCE TRENDING MORE NORTH. PRECIP TYPE SHOULD MAINLY BE SNOW BUT WILL STILL HAVE A SLIGHT CHANCE OF A SLEET/FREEZING RAIN MIX ALONG TO SOUTH OF THE ZERO DEGREE ISOTHERM ALOFT. NEXT WAVE OF PRECIPITATION ARRIVES LATER THIS MORNING INTO THE AFTERNOON WHEN ANOTHER MID LEVEL WAVE MOVING EAST THROUGH THE REGION MOVES OVER A SECONDARY COLD FRONT. LEANED AWAY FROM THE ECMWF WITH ITS FARTHER NORTH PLACEMENT OF QPF WITH ALL OTHER GUIDANCE MORE SOUTH WITH THE PRECIPITATION AXIS STARTING IN WEST- CENTRAL ND AND EXPANDING EASTWARD...WITH PRECIP CHANCES DEVELOPING SOUTH TODAY WITH TIME ALONG THE FROPA. MAINLY SNOW EXPECTED WITH TEMPS ALOFT SUBFREEZING BY THE ONSET OF PRECIPITATION OR VERY SHORTLY AFTER. AN INCH OF SNOW ACCUMULATION POSSIBLE BUT MOST LOCATIONS SHOULD REMAIN LESS THAN AN INCH AND CLOSER TO A FEW TENTHS. CHANCES FOR LIGHT SNOW PUSH SOUTH WITH TIME AND WILL END OVERNIGHT. GUSTY NORTHWEST WINDS ALREADY DEVELOPING ACROSS MY NORTHWEST BEHIND THE COLD FRONT WILL EXPAND SOUTH AND EAST. WITH CAA ONGOING THROUGH TODAY AND TONIGHT...DO NOT SEE THE WINDS TAPERING OFF MUCH THIS EVENING UNTIL AFTER MIDNIGHT WHEN PRESSURE RISES SUBSIDE. HIGHS FOR TODAY LIKELY ALREADY REACHED EARLY THIS MORNING WITH FALLING TEMPERATURES EXPECTED TODAY. OVERNIGHT LOWS FROM ZERO SOUTH TO 10 BELOW NORTH WILL COMBINE WITH THE WINDS TO RESULT IN ADVISORY LEVEL WIND CHILL TEMPERATURES SO WILL HOIST A WIND CHILL ADVISORY FOR ALL BUT THE SOUTH CENTRAL WHERE FORECAST WIND CHILLS REMAIN MARGINAL FOR AN ADVISORY. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 400 AM CST SAT NOV 29 2014 THE ONLY CONCERN FOR THE LONG TERM IS THE CONTINUATION OF WIND CHILL HEADLINES THROUGH ABOUT NOON ON MONDAY. AS TEMPERATURES CLIMB INTO THE SINGLE DIGITS ABOVE ZERO DURING THE DAY SUNDAY THE CHILLS WILL MODERATE OUT OF ADVISORY CRITERIA MOST AREAS...BUT VERY TEMPORARILY...AS A BITTERLY COLD SUNDAY NIGHT / MONDAY MORNING FORCE CHILLS BACK INTO THE 20S AND 30S BELOW ZERO NORTH AND EAST OF A LINE FROM WILLISTON THROUGH JAMESTOWN. THOSE OUTSIDE...AND NOT PROPERLY CLOTHED...SUNDAY NIGHT AND MONDAY MORNING WILL BE AT RISK FOR FROST BITE IN ABOUT 20 MINUTES. BECAUSE OF THE ONLY BRIEF PERIOD OUT OF ADVISORY THRESHOLDS...WILL NOT END THE ADVISORY AND KICK IT BACK IN TO EFFECT...RATHER...WILL KEEP IT GOING THROUGH THE DAY SUNDAY...AND RIGHT ON THROUGH MONDAY MORNING. SYNOPTICALLY IN THE LONG TERM...THE CENTER OF THE COLD POOL ALOFT PASSES JUST TO OUR NORTHEAST ON SUNDAY NIGHT WITH SURFACE HIGH PRESSURE NEAR ABERDEEN SOUTH DAKOTA FOR DAYBREAK MONDAY. LOCAL RESEARCH STUDIES SHOW THAT THIS IS A FAVORABLE LOCATION OF THE SURFACE FEATURE TO HAVE THE BOTTOM DROP OUT OF THE THERMOMETER AT BISMARCK. A BREEZY SOUTHWEST SURFACE FLOW SETS UP LATER MONDAY BEHIND THE HIGH AND AHEAD OF A WARM FRONT THAT MEANS BRIEF MODERATION IN TEMPERATURE FOR TUESDAY. TEMPERATURES MONDAY NIGHT COULD ACTUALLY BE RISING THROUGH THE NIGHT...ESPECIALLY SOUTHWEST. ANOTHER PIECE OF THE COLD AIR COMES THROUGH WEDNESDAY BEFORE A PROLONGED SPELL OF WARMER AIR FOR THE END OF THE WEEK AND THE WEEKEND GRACES US AS THE ARCTIC DOME RETREATS FARTHER NORTH INTO CANADA. NOTE THAT THE RECORD LOW AT BISMARCK FOR DECEMBER 1...MONDAY...IS -23 FROM 1893. WE ARE FORECASTING TEENS BELOW FOR ACTUAL AIR TEMPERATURES. SHOULD THAT BOTTOM FALL OUT...AS IS POSSIBLE...THAT WOULD BE A HECK OF A RECORD TO BREAK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 650 AM CST SAT NOV 29 2014 MVFR CIGS AT KISN EXPECTED TO IMPROVE BY THIS AFTERNOON. IFR/VLIFR CIGS AT KDIK WILL LIFT TO IFR-MVFR BY 18Z. MVFR CIGS AT KBIS- KMOT-KJMS THIS MORNING. CIGS EXPECTED TO IMPROVE TO VFR LATER TODAY INTO TONIGHT FROM NORTH TO SOUTH AS COLDER / DRIER AIR WORKS IN. UNTIL THEN EXPECT NORTHWEST WIND GUSTS UP TO 30 KNOTS WITH POCKETS OF MIXED PRECIPITATION OF -SN / -FZRA THROUGH 18Z...THEN MAINLY -SN. && .BIS WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY FROM 6 PM CST /5 PM MST/ THIS EVENING TO NOON CST /11 AM MST/ SUNDAY FOR NDZ017>019-031>033-040-041-043- 044. WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO NOON CST MONDAY FOR NDZ001>005-009>013-021>023-025-036-037. && $$ UPDATE...JPM SHORT TERM...NH LONG TERM...JPM AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
409 AM CST SAT NOV 29 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 400 AM CST SAT NOV 29 2014 FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE PRECIPITATION CHANCES THROUGH THE PERIOD AND VERY COLD AIR PUSHING SOUTH ACROSS THE REGION TODAY INTO TONIGHT. CURRENTLY...QUASI-ZONAL FLOW ALOFT OVER THE NORTHERN PLAINS THIS MORNING AS A BROAD UPPER LEVEL RIDGE CONTINUES TO BE FLATTENED BY A VIGOROUS UPPER LEVEL S/WV TROUGH MOVING INTO THE PACIFIC NORTHWEST. EMBEDDED MID LEVEL IMPULSES CONTINUE TO STREAM EAST ACROSS THE REGION WITHIN THE FLOW. LATEST HIGH RESOLUTION MODELS OF THE HRRR AND RAP INDICATE A CONTINUED CHANCE FOR LIGHT PRECIPITATION ACROSS THE NORTH THROUGH SATURDAY MORNING AS THE MID LEVEL IMPULSES INTERACT WITH A COLD FRONTAL FRONTAL BOUNDARY NOW MOVING SOUTHWARD ACROSS THE STATE. IMPULSE NOW OVER NORTHEASTERN MONTANA WILL PUSH THROUGH MY FAR NORTHWEST/NORTH CENTRAL BETWEEN NOW AND 13-15Z. MAINTAINED ELEVATED POPS FOR THIS FEATURE NEAR THE CANADIAN BORDER...TRIMMED FARTHER SOUTH WITH LATEST HR GUIDANCE TRENDING MORE NORTH. PRECIP TYPE SHOULD MAINLY BE SNOW BUT WILL STILL HAVE A SLIGHT CHANCE OF A SLEET/FREEZING RAIN MIX ALONG TO SOUTH OF THE ZERO DEGREE ISOTHERM ALOFT. NEXT WAVE OF PRECIPITATION ARRIVES LATER THIS MORNING INTO THE AFTERNOON WHEN ANOTHER MID LEVEL WAVE MOVING EAST THROUGH THE REGION MOVES OVER A SECONDARY COLD FRONT. LEANED AWAY FROM THE ECMWF WITH ITS FARTHER NORTH PLACEMENT OF QPF WITH ALL OTHER GUIDANCE MORE SOUTH WITH THE PRECIPITATION AXIS STARTING IN WEST- CENTRAL ND AND EXPANDING EASTWARD...WITH PRECIP CHANCES DEVELOPING SOUTH TODAY WITH TIME ALONG THE FROPA. MAINLY SNOW EXPECTED WITH TEMPS ALOFT SUBFREEZING BY THE ONSET OF PRECIPITATION OR VERY SHORTLY AFTER. AN INCH OF SNOW ACCUMULATION POSSIBLE BUT MOST LOCATIONS SHOULD REMAIN LESS THAN AN INCH AND CLOSER TO A FEW TENTHS. CHANCES FOR LIGHT SNOW PUSH SOUTH WITH TIME AND WILL END OVERNIGHT. GUSTY NORTHWEST WINDS ALREADY DEVELOPING ACROSS MY NORTHWEST BEHIND THE COLD FRONT WILL EXPAND SOUTH AND EAST. WITH CAA ONGOING THROUGH TODAY AND TONIGHT...DO NOT SEE THE WINDS TAPERING OFF MUCH THIS EVENING UNTIL AFTER MIDNIGHT WHEN PRESSURE RISES SUBSIDE. HIGHS FOR TODAY LIKELY ALREADY REACHED EARLY THIS MORNING WITH FALLING TEMPERATURES EXPECTED TODAY. OVERNIGHT LOWS FROM ZERO SOUTH TO 10 BELOW NORTH WILL COMBINE WITH THE WINDS TO RESULT IN ADVISORY LEVEL WIND CHILL TEMPERATURES SO WILL HOIST A WIND CHILL ADVISORY FOR ALL BUT THE SOUTH CENTRAL WHERE FORECAST WIND CHILLS REMAIN MARGINAL FOR AN ADVISORY. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 400 AM CST SAT NOV 29 2014 THE ONLY CONCERN FOR THE LONG TERM IS THE CONTINUATION OF WIND CHILL HEADLINES THROUGH ABOUT NOON ON MONDAY. AS TEMPERATURES CLIMB INTO THE SINGLE DIGITS ABOVE ZERO DURING THE DAY SUNDAY THE CHILLS WILL MODERATE OUT OF ADVISORY CRITERIA MOST AREAS...BUT VERY TEMPORARILY...AS A BITTERLY COLD SUNDAY NIGHT / MONDAY MORNING FORCE CHILLS BACK INTO THE 20S AND 30S BELOW ZERO NORTH AND EAST OF A LINE FROM WILLISTON THROUGH JAMESTOWN. THOSE OUTSIDE...AND NOT PROPERLY CLOTHED...SUNDAY NIGHT AND MONDAY MORNING WILL BE AT RISK FOR FROST BITE IN ABOUT 20 MINUTES. BECAUSE OF THE ONLY BRIEF PERIOD OUT OF ADVISORY THRESHOLDS...WILL NOT END THE ADVISORY AND KICK IT BACK IN TO EFFECT...RATHER...WILL KEEP IT GOING THROUGH THE DAY SUNDAY...AND RIGHT ON THROUGH MONDAY MORNING. SYNOPTICALLY IN THE LONG TERM...THE CENTER OF THE COLD POOL ALOFT PASSES JUST TO OUR NORTHEAST ON SUNDAY NIGHT WITH SURFACE HIGH PRESSURE NEAR ABERDEEN SOUTH DAKOTA FOR DAYBREAK MONDAY. LOCAL RESEARCH STUDIES SHOW THAT THIS IS A FAVORABLE LOCATION OF THE SURFACE FEATURE TO HAVE THE BOTTOM DROP OUT OF THE THERMOMETER AT BISMARCK. A BREEZY SOUTHWEST SURFACE FLOW SETS UP LATER MONDAY BEHIND THE HIGH AND AHEAD OF A WARM FRONT THAT MEANS BRIEF MODERATION IN TEMPERATURE FOR TUESDAY. TEMPERATURES MONDAY NIGHT COULD ACTUALLY BE RISING THROUGH THE NIGHT...ESPECIALLY SOUTHWEST. ANOTHER PIECE OF THE COLD AIR COMES THROUGH WEDNESDAY BEFORE A PROLONGED SPELL OF WARMER AIR FOR THE END OF THE WEEK AND THE WEEKEND GRACES US AS THE ARCTIC DOME RETREATS FARTHER NORTH INTO CANADA. NOTE THAT THE RECORD LOW AT BISMARCK FOR DECEMBER 1...MONDAY...IS -23 FROM 1893. WE ARE FORECASTING TEENS BELOW FOR ACTUAL AIR TEMPERATURES. SHOULD THAT BOTTOM FALL OUT...AS IS POSSIBLE...THAT WOULD BE A HECK OF A RECORD TO BREAK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 400 AM CST SAT NOV 29 2014 MVFR CIGS HAVE MOVED INTO KISN. VFR CONDITIONS OVER WESTERN AND CENTRAL NORTH DAKOTA WILL ALL BECOME MVFR IN THE WAKE OF AN ARCTIC FRONTAL PASSAGE AFTER MIDNIGHT TONIGHT NORTH (KMOT)...AND SATURDAY MORNING SOUTH (KBIS-KJMS). IFR/VLIFR CIGS WILL MOVE INTO KDIK 09-11Z AND SHOULD IMPROVE TO IFR-MVFR 15-18Z. LIGHT SNOW THIS MORNING POSSIBLE FOR KISN-KMOT WILL IMPACT VIS TO MVFR-IFR...AND FOR KDIK-KBIS LATER TODAY. NORTHWESTERLY WIND GUSTS UP TO 30 KNOTS WILL BE POSSIBLE BEHIND THE FRONT THROUGH SATURDAY AFTERNOON AND EVENING. && .BIS WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY FROM 6 PM CST /5 PM MST/ THIS EVENING TO NOON CST /11 AM MST/ SUNDAY FOR NDZ017>019-031>033-040-041-043- 044. WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO NOON CST MONDAY FOR NDZ001>005-009>013-021>023-025-036-037. && $$ SHORT TERM...NH LONG TERM...JPM AVIATION...NH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
406 AM CST SAT NOV 29 2014 .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 355 AM CST SAT NOV 29 2014 CHALLENGE TODAY WILL BE WEAK MIXED PRECIP CHANCES AND TEMPS AND THEIR POTENTIAL NON-DIURNAL CURVE. MODELS IN FAIR AGREEMENT AND USED A BLEND FOR THE FORECAST WITH A LEAN TOWARD THE LATEST RUNS OF THE MESOSCALE SUITE...RAP/HRRR...FOR THEIR HANDLE ON POPS/PRECIP PLACEMENT AND WINDS TODAY. REGIONAL RADARS CONTINUE TO SHOW RETURNS ACROSS THE NORTHERN PLAINS AS WEAK DISTURBANCES MOVE ALONG A WELL DEFINE BAROCLINIC ZONE. HOWEVER DUE TO A DRY MID LAYER EVIDENT ON BUFR SOUNDINGS LITTLE PCPN ACTUALLY REACHING THE SFC. THERMAL COLUMN CONTINUES TO WARM THIS MORNING AS 850MB TEMPS RISE TO 0C AS FAR NORTH AS HWY 2 AND TO PLUS 10C ALONG THE ND/SD BORDER. AS A RESULT ANY PRECIP THAT DOES SUCCESSFULLY FALL THROUGH THE DRY LAYER MAY HAVE A MIXED PHASE THIS MORNING. AS SFC TROUGH TRAVERSES N SD TODAY BAROCLINIC ZONE TIGHTENS ACROSS THE CWFA WITH NW WINDS IN THE DVL BSN AND SE WINDS CONTINUING IN WCTL MN. TEMPS WILL PROBABLY HOLD STEADY THIS AM AND BEGIN TO FALL IN THE DVL BSN AND N RRV THIS AFTERNOON AS THE SFC LOW MOVES EAST INTO MN AND THE TIGHT BAROCLINIC ZONE SHIFTS SE WITH THERMAL COLUMN COOLING. THIS WILL ALLOW ANY PRECIP TO BECOME ALL SNOW THIS AFTERNOON. THE BEST PUSH OF 925MB TEMP ADVECTION DEVELOPS BETWEEN 00 AND 12Z WITH THE SFC HIGH PRESSURE BEGINNING TO NOSE INTO WESTERN ND. WITH WESTERLY SFC WIND AND NOT DUE NORTHERLY LIKE THIS PAST WEDNESDAY EXPECTING TO SEE MAX SOME MINIMAL TEMP RISE DURING THE DAY SUNDAY. WIND CHILL VALUES WILL BE NEAR OR BELOW CRITERIA FOR HEADLINES AS A RESULT. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 355 AM CST SAT NOV 29 2014 SUNDAY NIGHT TO MONDAY NIGHT WILL BARE THE BRUNT OF THE COLDEST PART OF THE AFOREMENTIONED AIRMASS WITH THE SFC HIGH CENTER CROSSING THE NORTHERN PLAINS JUST SOUTH OF THE FA MOVING FROM W ND THRU SD AND INTO S MN BY MONDAY. THIS WILL BRING THE -25C AT 850MB ACROSS THE NORTHERN HALF OF THE CWFA DURING MONDAY MORNING. ALLOWING MIN TEMPS TO RANGE FROM 10 TO 20 BELOW. A SLOW AND STEADY TEMP RISE IS EXPECTED DURING THE DAY AND INTO THE OVERNIGHT AS SOUTHERLY WINDS SET UP IN RETURN FLOW ON THE BACKSIDE OF THE HIGH MONDAY LATE. 00Z ECMWF/GFS ARE IN GOOD AGREEMENT TUESDAY THROUGH FRIDAY. 500 MB SHORTWAVE WILL ROTATE AROUND THE UPPER LOW OVER HUDSON BAY AND ALONG THE CANADIAN BORDER TUESDAY GIVING SOME LIGHT PRECIP CHANCES. AFTER THIS SHORTWAVE PASSES 500 MB FLOW BECOMES MORE ZONAL AND TEMPS MODERATE TO CLOSER TO EARLY DECEMBER AVERAGES WHICH ARE HIGHS IN THE MID-UPR 20S AND LOWS 10-15. GENERALLY DRY PERIOD WED-FRI...THOUGH SOME VERY LOW POPS WERE PUT IN FOR PARTS OF THE AREA DUE TO A WEAK SHORT WAVE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1141 PM CST FRI NOV 28 2014 MVFR CIGS ARE EXPECTED OVER MOST OF THE AREA OVERNIGHT AND THROUGH MUCH OF SATURDAY. LOW PRESSURE SYSTEM IN WESTERN DKTAS WILL EDGE INTO THE EASTERN DKTAS THROUGH THE OVERNIGHT AND SPREAD ADDITIONAL MAINLY MVFR BANDS OF LIGHT MIXED PRECIP INTO THE AREA...AFT 09Z INTO THE DVL BASIN AND AFT 11Z INTO THE CENTRAL RED RIVER BASIN. POINTS EASTWARD INTO NORTHWEST MN WILL LIKELY SEE MIXED PRECIP AFT 12Z AND THROUGHOUT THE MORNING HOURS. LATEST RUC HAS THE TROF AXIS CROSSING THE RRV BY 15Z...AFT WHICH WE WILL SEE INCREASING NORTHWEST WINDS AND ADDN PERIODS OF MVFR CIGS AND VSBYS IN VERY LIGHT SNOW FROM MIDDAY INTO THE EARLY AFTERNOON. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...JK LONG TERM...JK/RIDDLE AVIATION...GUST
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1142 PM CST FRI NOV 28 2014 .UPDATE... ISSUED AT 1141 PM CST FRI NOV 28 2014 NO SIGNIFICANT UPDATES ARE PLANNED FOR THIS EVENING. RADAR IMAGERY CONTINUES TO SHOW A BAND OF VERY LIGHT SNOW MOVING ACROSS NORTHWEST AND NORTHCENTRAL MINNESOTA... BUT WITH NO SIG ACCUMULATIONS OR RESTRICTIONS TO VISIBILITY EXPECTED. LOW PRESSURE SYSTEM IN WESTERN ND WILL SLOWLY MOVE INTO THE AREA OVERNIGHT WITH ADDITIONAL LIGHT WARM FRONTAL PRECIP IN THE AM WITH POST /COLD/ FRONTAL PRECIPITATION EXPECTED THROUGH MIDDAY AND THE AFTERNOON PERIOD. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 316 PM CST FRI NOV 28 2014 PRECIP CHANCES AND TYPE WILL BE THE MAIN HEADACHES FOR THE PERIOD. POSITIVELY TILTED TROUGH CONTINUES TO DIG ONTO THE WEST COAST WITH FAST NEAR ZONAL FLOW OVER THE NORTHERN PLAINS. SFC LOW PRESSURE CONTINUES TO HANG OUT IN EASTERN ND WITH A STRONG BAROCLINIC ZONE STRETCHING FROM NORTHWEST TO SOUTHEAST ACROSS NORTH DAKOTA AND MINNESOTA. THERE HAS BEEN A BAND OF SCATTERED MIXED PRECIP ACROSS THE CENTRAL CWA THAT FITS FAIRLY WELL WITH THE 800MB FRONTOGENESIS AS SEEN IN THE RAP13 ANALYSIS. THIS BAND SHOULD MOVE NORTHEASTWARD AS THE SFC LOW MOVES OUT INTO ND TONIGHT...WITH THE FRONT LIFTING TOWARDS THE CANADIAN BORDER. CONTINUED TO KEEP HIGH CHANCE POPS GOING FOR MAINLY THE NORTHERN CWA...WITH A MIX OF PRECIP ALONG THE SOUTHERN EDGE OF THE PRECIP. WILL HAVE TO WATCH FOR FREEZING DRIZZLE POSSIBILITIES FURTHER SOUTH...BUT NOT CONFIDENT ENOUGH TO INCLUDE IT AT THIS POINT. THE UPPER TROUGH WILL BEGIN TO MOVE INTO THE NORTHERN ROCKIES TOMORROW...WITH SFC LOW PRESSURE QUICKLY MOVING OFF TO THE EAST. ANOTHER COLD FRONT BRINGING ARCTIC AIR WILL PLUNGE SOUTHWARD ACROSS THE CWA. THINK THAT A NON-DIURNAL TEMPERATURE PATTERN IS PROBABLE WITH RISING TEMPS TONIGHT AS THE WARM AIR SURGES NORTH AND FALLING TOMORROW AFTERNOON AT LEAST IN THE NORTH AS THE COLD FRONT MOVES SOUTH. WARM AIR ALOFT WILL BE FIRMLY IN PLACE SATURDAY MORNING...AND WITH COLD TEMPS AT THE SFC...SOME FREEZING RAIN AND SLEET ARE POSSIBLE. THIS MIXED PRECIP SHOULD MOVE SOUTH AND EVENTUALLY CHANGE OVER TO ALL SNOW AS THE COLUMN COOLS THROUGHOUT THE DAY ON SATURDAY. AMOUNTS WILL BE VERY LIGHT NO MATTER WHAT THE PRECIP TYPE...SO WILL INCLUDE AN SPS FOR TONIGHT AND TOMORROW MENTIONING VERY LIGHT MIXED PRECIP IN SPOTS. THE UPPER TROUGH WILL CONTINUE TO DIG INTO THE NORTHERN PLAINS...WITH SFC HIGH PRESSURE ARRIVING IN THE REGION. NORTH WINDS SHOULD BECOME QUITE BREEZY WITH STRONG COLD AIR ADVECTION. TEMPS SHOULD GO DOWN BELOW ZERO IN THE NORTHERN COUNTIES WITH THE COLD AIR EVEN WITH WINDS AND LINGERING CLOUDS. THERE COULD BE SOME LIGHT SNOW IN THE MID LEVEL BAROCLINIC ZONE REMAINING OVER THE AREA...BUT PRETTY SCATTERED AND LIGHT WITH NOT MUCH ACCUMULATION. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 316 PM CST FRI NOV 28 2014 SUNDAY AND MONDAY...COLD AND DRY WITH HIGH PRESSURE OVER THE AREA. HIGHS ON SUNDAY WILL STRUGGLE TO GET NEAR ZERO AND WITH CLOUDS DIMINISHING WE COULD AGAIN DROP CLOSE TO THE 20 BELOW MARK IN SOME AREAS SUNDAY NIGHT. WARM AIR ADVECTION KICKS IN AS THE SFC HIGH MOVES EAST ON MONDAY...BUT WITH BREEZY WINDS AND TEMPS STILL IN THE SINGLE DIGITS...IT WILL STILL FEEL VERY RAW. WILL HAVE TO WATCH FOR WIND CHILLS APPROACHING ADVISORY MARK BUT TOO SOON TO MENTION AT THIS POINT. MONDAY NIGHT THROUGH FRIDAY...THIS PERIOD BEGINS WITH A DEPARTING SURFACE HIGH PRESSURE CENTERED OVER IOWA AND DEVELOPING LOW PRESSURE OVER SASKATCHEWAN. SOUTHERLY GRADIENT BECOMES QUITE STRONG...WITH 45 TO 55 KT 850 JET AND 45KT 925 JET WINDS TRAVERSING CWFA. SINCE THIS WILL OCCUR OVERNIGHT MONDAY/EARLY TUESDAY DO NOT THINK FULL GRADIENT POTENTIAL WILL BE REALIZED. BUT IT SHOULD BE BREEZY AND GUIDANCE PICKS UP ON THIS. SHORT WAVE EMBEDDED IN AMPLIFYING UPPER FLOW MOVES RAPIDLY EAST ALONG THE INTERNATIONAL BORDER...PUSHING A COLD FRONT THROUGH THE CWA TUESDAY. AS SURFACE LOW FORECAST TO TRACK NEAR/ALONG CANADIAN BORDER ONLY SLGT CHC POPS GIVEN OVER EASTERN PART OF CWFA. BEHIND THE FRONT TUESDAY NIGHT INTO WEDNESDAY EXPECT ANOTHER FAIRLY RAPID COOLDOWN. TRAJECTORIES BOTH SURFACE AND ALOFT UNDER FLATTER NORTHWEST FLOW WITH RELATIVELY HIGHER 1000-500KPA THICKNESS SUGGEST THE AIRMASS WILL NOT BE QUITE AS COLD AS RECENT INTRUSIONS. SURFACE HIGH MOVES RAPIDLY EAST OF THE CWFA WEDNESDAY NIGHT INTO THURSDAY. TEMPERATURES MODERATE NICELY AT THE END OF THIS PERIOD WITH TIMING DIFFERENCES RELATIVELY SLIGHT. AT THIS TIME NO SIGNIFICANT WAVES DEPICTED BY MODELS SO HAVE KEPT WED - FRI PERIOD PRECIPITATION FREE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1141 PM CST FRI NOV 28 2014 MVFR CIGS ARE EXPECTED OVER MOST OF THE AREA OVERNIGHT AND THROUGH MUCH OF SATURDAY. LOW PRESSURE SYSTEM IN WESTERN DKTAS WILL EDGE INTO THE EASTERN DKTAS THROUGH THE OVERNIGHT AND SPREAD ADDITIONAL MAINLY MVFR BANDS OF LIGHT MIXED PRECIP INTO THE AREA...AFT 09Z INTO THE DVL BASIN AND AFT 11Z INTO THE CENTRAL RED RIVER BASIN. POINTS EASTWARD INTO NORTHWEST MN WILL LIKELY SEE MIXED PRECIP AFT 12Z AND THROUGHOUT THE MORNING HOURS. LATEST RUC HAS THE TROF AXIS CORSSING THE RRV BY 15Z...AFT WHICH WE WILL SEE INCREASING NORTHWEST WINDS AND ADDN PERIODS OF MVFR CIGS AND VSBYS IN VERY LIGHT SNOW FROM MIDDAY INTO THE EARLY AFTERNOON. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...GUST SHORT TERM...JR LONG TERM...JR/EWENS AVIATION...GUST
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1046 PM EST SUN NOV 30 2014 .SYNOPSIS... A SHARP COLD FRONT WILL SAG THROUGH THE OHIO VALLEY TONIGHT. LIGHT RAIN WILL ACCOMPANY THIS FRONT FOR MOST LOCATIONS...AS WELL AS A TWENTY DEGREE TEMPERATURE DROP IN THE FIRST FEW HOURS AFTER IT PASSES. THE FRONT WILL SLOW A LITTLE ON ITS SOUTHWARD TREK ON MONDAY AS IT SAGS INTO VIRGINIA AND TENNESSEE...AND WEAK DISTURBANCES SHIFTING NORTHEAST ALONG THE FRONT MONDAY AFTERNOON AND EVENING WILL LINGER RAIN ACROSS PORTIONS OF SOUTHERN OHIO AND NORTHERN KENTUCKY. A LITTLE LIGHT SNOW MAY MIX IN ACROSS THIS AREA BEFORE PRECIPITATION ENDS MONDAY NIGHT. TEMPERATURES WILL BE MUCH COLDER ON MONDAY INTO TUESDAY...BEFORE THE FRONT RETURNS NORTHWARD BY MIDWEEK WITH MILD AIR AND A RETURNING THREAT FOR LIGHT RAIN SHOWERS. && .NEAR TERM /THROUGH MONDAY/... LATEST SFC ANALYSIS SHOWS COLD PUSHING INTO NW OHIO FROM JUST WEST OF TO JUST NW OF DAY. NARROW BAND OF LIGHT RAIN SHOWERS INVOF OF THIS BOUNDARY ASSOCIATED WITH FAVORABLE LOW LEVEL MOISTURE CONVERGENCE. THIS AXIS OF PRECIPITATION TO SAG SOUTH THRU ILN/S FA WITH THE FRONT OVERNIGHT. HAVE ALLOWED PCPN TO EXPAND SOME NORTH OF THE BOUNDARY LATE TONIGHT AS MORE FAVORABLE 850 MB CONVERGENCE COMES INTO PLAY. STRONG COLD AIR ADVECTION WITH TEMPERATURES ALREADY DROPPING INTO THE MID/UPR 40S OVER NW OHIO. HAVE MADE SLIGHT ADJUSTMENT TO HOURLY TEMPERATURES ALLOWING FOR QUICKER PUSH OF COLD AIR. EXPECT LOWS BY MORNING TO RANGE FORM THE LOWER 30S NW TO THE MID 40S SE. PREV DISCUSSION... OVERLAYING YESTERDAY/S FORECAST SOUNDINGS VALID 30.12Z AT ILN WITH ILN RAOB AS VERIFICATION HAS SHOWN THAT NWP GUIDANCE HAS VASTLY OVERESTIMATED MIXING RATIOS/SATURATION BELOW 900MB LAST NIGHT THROUGH TODAY. THUS...DEPTH OF LOW LEVEL SATURATED LAYER HAS REMAINED ABOUT 1KM TO 1.2KM DEEP FROM LATE LAST NIGHT THROUGH MUCH OF THE DAY AND HAS KEPT DZ/RA-- PRODUCTION AT BAY THUS FAR. WOULD MUCH PREFER TO SEE THE SATURATED LAYER EXCEED 1.5KM AND CLOSER TO 2.0KM FOR A LOW LEVEL SATURATED LAYER TO PRODUCE -DZ/RA-- IN THE ABSENCE OF STRONGER LOW LEVEL SHORTWAVE TROUGH OR LOWER 100MB BOUNDARY LIKE WHAT WE HAVE IN THE OPEN WARM SECTOR TODAY. CLOUD CIGS REMAIN STUBBORNLY IN THE 2-3KFT LAYER AGL SO WE/VE BEEN PROGRESSIVELY DELAYING MEASURABLE RAIN THREATS. THIS HAS ALLOWED FOR EVEN WARMER READINGS /MANY LOCATIONS IN MID 60S/ AND DWPTS HAVE CHECKED IN ABOUT 5F-7F LOWER...STRUGGLING TO BREACH 50F...THUS T/TD SPREADS ARE > 10F MOST LOCATIONS. ALL THAT STARTING TO CHANGE HOWEVER AS SHARP/ARCTIC COLD FRONT APPROACHES AND GLANCING BLOW FROM PARENT HEIGHT FALLS SWEEPING ALONG THE US/CANADIAN BORDER IS FORCING A GRADUAL INCREASE IN SYNOPTIC ASCENT ACROSS THE GREAT LAKES. KIWX WSR-88D HAS RECENTLY DEPICTED BLOSSOMING ECHOES AHEAD OF THE COLD FRONT WHICH WAS DEPICTED AT 30.18Z TO RUN FROM GRAND RAPIDS /MI/ TO CHICAGO TO SPRINGFIELD /IL/. THE FURTHER SOUTH/WEST YOU TRAVEL ALONG THE FRONT IN IL/MO/OK...THE SHARPER THE TEMP GRADIENT /30F ACROSS ONE OR TWO COUNTIES IN SOME CASES/. HOWEVER...LACK OF BLOCKING IN THE FAST QUASI-ZONAL FLOW WILL KEEP THE ARCTIC POOL OF BITTERLY COLD AIR TRUCKING ON EAST /AND MODIFYING/ VS. SOUTHEAST AND THUS OUR LOCAL AREA BECOMES MORE AND MORE REMOVED FROM THE COLDEST AIR W/TIME. THUS...TEMP GRADIENT WILL SLOWLY RELAX ALONG THE FRONT IN THE NEXT 12 HOURS. WILL STILL BE AN IMPRESSIVE FRONT AS IT COMES THROUGH TONIGHT...WITH UP TO A 20 DEGREE TEMP DROP OVER 3-4 HOURS AND A RATHER ABRUPT WIND SHIFT TO THE NORTHWEST /WITH GUSTS/. HAVE FOLLOWED RAW 2M MODEL TEMP BLEND CLOSELY TO MITIGATE MINOR SPEED DIFFERENCES OF FRONTAL PASSAGE. THIS PUTS FRONT TO SCIOTO COUNTY /OH/ BY 12Z MONDAY..WITH TEMPS AT SUNRISE ON MONDAY LIKELY RANGING FROM NEAR OR JUST BELOW FREEZING /CELINA OH/ TO THE LOW TO MID 50S /PORTSMOUTH/. HAVE USED A BLEND OF NCEP HI-RES WINDOW GUIDANCE /ARW AND NMM CORES/ WITH SUBJECTIVE INTERPOLATION OF 30.17Z ESRL HRRR FOR TIMING OF RAIN WITH FRONTAL PASSAGE TONIGHT. THESE DATA SUGGEST WE WILL CONTINUE TO SEE SCT AREAS OF RAIN DEVELOP IMMEDIATELY AHEAD OF THE COLD FRONT AND A FINE LINE OF LIGHT RAIN DEVELOP ALONG/IMMEDIATELY BEHIND THE FRONT AND SWEEP THROUGH THE AREA PARTICULARLY AFTER 00Z. RECENT RADAR TRENDS TO OUR NW SUPPORT THIS REASONING. ALREADY SEEING SW-NE ORIENTED BANDS OF -DZ ACRS WCNTL OH NOW IN FRONT OF PRIMARY FINE LINE ALONG FRONT. KEEPING A 60-75% OF MEASURABLE RAIN AT MOST LOCATIONS WITH THE FRONTAL PASSAGE TONIGHT. AM PROBABLY TO LONG /DURATION/ WITH THREAT OF RAIN GIVEN DEPICTIONS IN SIMULATED REFLECTIVITY BUT TRIED TO KEEP RAIN TO NO MORE THAN 2-3 HOURS AT ANY ONE LOCATION. FRONT WILL BEGIN TO SLOW OVER KY TOMORROW AS IT SAGS SOUTH OF STRONGER/FASTER WESTERLY FLOW...BECOMING MORE PARALLEL THE DEEP LAYER FLOW. THIS SHOULD SERVE TO LINGER RAIN IN NORTHERN KY/FAR SOUTHERN OHIO /APPROX SOUTH OF CINCINNATI TO CHILLICOTHE LINE/ INTO THE AFTERNOON. LITTLE CONCERNED WITH THE 30.12Z RUNS OF GFS/ECMWF WHICH ENHANCE POST FRONTAL PCPN BANDS LATE MORNING/AFTN ALONG AND SOUTH OF AFOREMENTIONED LINE. QPF SEEMS LIGHT...BUT BOTH MODELS SUGGESTING 0.10 TO 0.20" QPF DEVELOPING IN RESPONSE TO MID LEVEL FRONTOGENESIS /FGEN/ SIGNAL THAT ACCOMPANIES BRIEF WINDOW OF RIGHT ENTRANCE ULJ FORCING THAT HAS WEAK SHORTWAVE/VORTICITY EMBEDDED IN THIS ANTICYCLONIC PORTION OF THE UPPER JET. THIS CAUSES CONCERN BECAUSE OF MARGINAL/CRITICAL THERMAL STRUCTURE OF THE BOUNDARY LAYER BY THE TIME...AS CAA WILL BE STRONG AND TEMPS/DWPTS WILL HAVE FALLEN/OR BE FALLING TO NEAR FREEZING...ESP ALONG OHIO RIVER. CLOSER INSPECTION OF 30.12Z LAYER MAX WET BULB TEMPS SUGGESTS 30.12Z ECMWF IS VERY BULLISH/FAST WITH THE CAA WHILE 30.12Z NAM/SREF MEAN THE SLOWEST...WITH 30.12Z GFS A MIDDLE OF THE ROAD SOLUTION. UNFORTUNATELY 30.12Z ECMWF IS ALSO MOST ROBUST WITH ITS LIGHT QPF DISTRIBUTION IN THE WAKE OF THE FRONT WITH THE STRONGEST CONTRIBUTION FROM THE UPPER JET - SO THIS PRESENTS A LOWER-END THREAT OF A PERIOD OF SNOW /VIA WET BULB PROCESSES AND CAA/ FOR PORTIONS OF NORTHERN KY AND/OR SRN OHIO MONDAY BEFORE PRECIPITATION WANES. HAVE NOT REALLY SEEN THIS THREAT ON PRIOR PARALLEL GFS...OPNL NAM...OR HIGHER RES GEM/HIRES-WINDOW RUNS...THESE PUSH FRONT FURTHER SOUTH AND THUS POST FRONTAL PCPN BANDS DEVELOP FURTHER SOUTH AND IN WARMER AIR /RAIN/. ALSO...COARSE 30.12Z ECMWF FORECAST SOUNDINGS /NOT NATIVE MODEL RES/ SUGGESTS MID LEVEL DRY AIR MAY INHIBIT MUCH PRECIP PRODUCTION AND PERHAPS HIGHER QPF DEPICTION FURTHER NORTH INTO COLD AIR A FUNCTION OF COARSE GRID RESOLUTION. SO MAIN CHANGE TO FORECAST WAS TO 1) LINGER HIGHER END RAIN CHANCES IN THE SOUTH ON MONDAY LATE MORNING AND AFTERNOON AND 2) ALLOW FOR THIS TO MIX WITH SNOW AS A START WITHOUT ANY ACCUMULATION. UPCOMING SHIFTS WILL NEED TO MONITOR FOR WHAT APPEARS TO BE A LOWER END/OUTLIER THREAT FOR A STRIPE OF LIGHT/WET ACCUMULATIONS IN OUR SOUTH ON MONDAY AFTN SHOULD A MORE ROBUST COLDER/WETTER ECMWF SCENARIO GARNER MORE NWP SUPPORT. && .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... BATCH OF MID LEVEL FGEN FORCING/WEAK VORT MAX AND RIGHT ENTRANCE REGION OF UPPER JET SHIFTS EAST LATER MONDAY NIGHT AND THUS EXPECT A PERIOD OF DRY CONDITIONS FROM MONDAY EVENING INTO TUESDAY AS 1045MB ARCTIC HIGH PRESSURE MOVES ACROSS SERN CANADA AND OUR SOURCE REGION AIRMASS EMANATES FROM THIS FEATURE ON NELY FLOW. A CHILLY MONDAY NIGHT IN THE MID 20S TO AROUND 30 BEFORE BACKING LOW AND MID LEVEL FLOW ALREADY STARTS TO ALLOW MIXING/EROSION OF THE VERY SHALLOW ARCTIC AIRMASS BY TUESDAY. AM ALLOWING MAX TEMPS ON TUESDAY BACK NEAR 40F BUT WAA WILL BE ONGOING ESPECIALLY JUST OFF THE SURFACE SO THESE READINGS COULD BE A LITTLE COOL GIVEN 925MB TEMPS BY MID AFTERNOON WILL BE 0C TO +5C ALREADY IN THE STRENGTHENING WAA REGIME. RATHER DECENT S/W TROUGH DIGGING THROUGH MN/WI TUESDAY NIGHT /INDUCING THE BACKING FLOW OVER THE OHIO VALLEY/ WILL ALLOW REMNANT MOISTURE/ISENTROPIC ASCENT OVER THE SHALLOW COLD DOME TO PERHAPS PRODUCE SOME LIGHT RAIN/DRIZZLE ESPECIALLY IN THE AREAS EAST OF I-71 TUESDAY NIGHT. BOUNDARY LAYER TEMPS SHOULD RISE THROUGH THE NIGHT...SO HAVE KEPT ANY POTENTIAL OF LIGHT FREEZING RAIN OUT OF THE FORECAST FOR TUESDAY NIGHT. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... OUR REGION WILL REMAIN UNDER THE INFLUENCE OF A PROGRESSIVE ZONAL FLOW PATTERN THROUGH AT LEAST THE END OF THE WORK WEEK...ALLOWING FOR MOISTURE TO CONTINUE TO STREAM IN FROM THE WEST/SOUTHWEST. AS IS TYPICAL IN A MORE PROGRESSIVE FLOW PATTERN...THE MODELS ARE STRUGGLING WITH THEIR TIMING AND PLACEMENT OF SEVERAL EMBEDDED SHORTWAVES. AS A RESULT...IT IS TOUGH TO RULE OUT A CHANCE OF RAIN WEDNESDAY THROUGH FRIDAY. THE MODELS DO SEEM TO BE TRENDING TOWARD THE BETTER MOISTURE/FORCING AFFECTING MORE OF OUR SOUTHERN FA THOUGH...SO WILL TREND POPS ACCORDINGLY WITH THE LOWEST POPS NORTHWEST AND THE HIGHEST IN THE SOUTHEAST. DUE TO THE TIMING ISSUES THOUGH...WILL KEEP POPS IN CHANCE CATEGORY OR LOWER. THE LOW LEVELS SHOULD REMAIN WARM ENOUGH TO SUPPORT PRIMARILY RAIN...BUT DEPENDING ON THE EXACT TIMING AND PLACEMENT...SOME SNOW COULD MIX IN ACROSS THE NORTH THURSDAY NIGHT INTO FRIDAY. TEMPERATURES SHOULD REMAIN FAIRLY SEASONABLE THROUGH FRIDAY...WITH HIGHS GENERALLY IN THE 40S AND OVERNIGHT LOWS MOSTLY IN THE 30S. THE MID LEVEL FLOW PATTERN WILL BEGIN TO AMPLIFY THROUGH THE WEEKEND WITH SOME MID LEVEL RIDGING DEVELOPING ACROSS THE OHIO VALLEY REGION. THIS WILL ALLOW FOR SOME DRYING THROUGH THE WEEKEND ALONG WITH SLIGHTLY WARMER TEMPERATURES. && .AVIATION /04Z MONDAY THROUGH FRIDAY/... SFC FRONT JUST ENTERING NW OHIO WILL SWEEP SOUTH THRU THE TAF SITES TONIGHT. VFR CIGS WILL DROP TO MVFR AND THEN TO IFR UNTIL MONDAY MORNING. LIGHT RAIN WILL ACCOMPANY THE IFR CEILINGS. EXPECT IMPROVEMENT TO MVFR MONDAY MORNING AND THEN VFR DURG THE AFTN. SOUTHWEST WINDS GUSTING OVER 20 KNOTS WILL SHIFT TO NORTH WITH FRONTAL PASSAGE LATE TONIGHT. NORTH WINDS AT 10 TO 15 KTS WILL BECOME NORTHEAST BY MONDAY EVENING. OUTLOOK...MVFR CEILINGS POSSIBLE TUESDAY NIGHT INTO THURSDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...BINAU NEAR TERM...AR SHORT TERM...BINAU LONG TERM...JGL AVIATION...CONIGLIO
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
957 PM EST SUN NOV 30 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE AREA TONIGHT. HIGH PRESSURE WILL BUILD ACROSS THE GREAT LAKES AND PASS NORTH OF OH/PA BETWEEN MONDAY AND TUESDAY. THE NEXT COLD FRONT CROSSES ON WEDNESDAY WITH HIGH PRESSURE BUILDING OVER THE LAKES ON THURSDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... THE DEFINED BAND OF SHRA ALONG THE COLD FRONT HAS NOW DROPPED SE THRU NW OH AND WILL SOON BE ALONG A CLE TO MNN LINE. WILL MAINTAIN THE PROGRESSION OF LIGHT RAIN CHANCES 50-70 PERCENT ACROSS THE AREA TONIGHT. MILD TEMPERATURES UNTIL THE FRONT PASSES. PRECIP WILL LIKELY EXIT BEFORE THE AIR GETS COLD ENOUGH FOR SNOW. TEMPERATURES BY 6 AM WILL BE IN THE 30S WITH A CONTINUED DROP INTO MID MONDAY MORNING. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/... HAVE REDUCED PRECIPITATION CHANCES ON MONDAY TO JUST A FEW FLURRIES FOR THE SNOWBELT. THE COLDER AIR IS SLOW TO SINK SOUTHWARD AND INVERSION REMAINS LOW. WILL STILL HAVE SOME LAKE CLOUDS AND AWAY FROM THE LAKE WILL LIKELY MAINTAIN SOME MID/HIGH CLOUDINESS WITH THE FRONTAL ZONE HANGING ACROSS THE OHIO VALLEY WITH ZONAL FLOW. TEMPERATURES WILL GO NO WHERE MONDAY AND WILL STAY IN THE LOWER AND MID 30S. THE COLDEST AIR WILL STAY REMOVED FROM OUR AREA AND BY TUESDAY WE BEGIN TO WARM SLIGHTLY WITH MOISTURE BEING DRAWN NORTHWARD AGAIN. TIMING FOR THE NEXT COLD FRONT IS FOR WEDNESDAY. AGAIN MOISTURE IS LIMITED AND MOST OF THE DYNAMICS PASS TO THE NORTH. KEPT THE LOW PRECIP CHANCES. && .LONG TERM /THURSDAY THROUGH SUNDAY/... HIGH PRESSURE WILL ACROSS SOUTHERN ONTARIO INTO QUEBEC BY THURSDAY NIGHT. THE MODELS THEN STRUGGLE ON THE TIMING OF THE NEXT PIECE OF JET ENERGY MOVING THROUGH THE SOUTHERN JET STREAM. CURRENT THINKING IS THAT MOS OF THE MOISTURE WILL REMAIN SOUTH OF THE OHIO RIVER VALLEY UNTIL THURSDAY NIGHT INTO FRIDAY. HOWEVER CONFIDENCE REMAINS LOW WITH THIS SCENARIO AND HAVE NOT GONE ANY HIGHER THAN CHANCE POPS FOR ANY PORTION OF THE COUNTY WARNING AREA. THURSDAY WILL BE THE COOLEST DAY OF THE LONG TERM WITH HIGHS REMAINING IN THE 30S. NEAR SEASONAL TEMPERATURES ARE ANTICIPATED THROUGH DAY 7. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... COLD FRONT ABOUT TO MOVE INTO KTOL THIS HOUR. MAINLY VFR AHEAD OF THE BOUNDARY WITH CONDITIONS DROPPING THROUGH MVFR TO IFR BEHIND. USING THE HRRR WIND SHIFT ATTEMPTED TO TIME FRONT ACROSS THE AREA REACHING KCLE BETWEEN 03-04Z AND KERI KCAK AND KYNG 04-05Z. EXPECT BRIEF MODERATE RAIN POSSIBLE WITH FRONT AS RADAR IS SHOWING 40 DBZ WITHIN THE FINE LINE. OTHERWISE MVFR TO IFR IN LIGHT RAIN DRIZZLE AND FOG BEHIND THE FRONT FOR THE OVERNIGHT AND INTO MONDAY MORNING BEFORE IMPROVING TO VFR DURING THE LATE MORNING AND AFTERNOON. .OUTLOOK...NON VFR POSSIBLE TUESDAY AFTERNOON THROUGH WEDNESDAY AND AGAIN FRIDAY. && .MARINE... UPDATE...COLD FRONT NOW DROPPING SOUTHEAST OF THE LAKE. WILL ISSUE SMALL CRAFT ADVISORY FOR THE CENTRAL SECTION STARTING AT 4AM. WAVES SHOULD BUILD TO 3 TO 5 FEET BY LATE TONIGHT. PREVIOUS...WINDS HAVE STARTED TO DECREASE SLIGHTLY THIS AFTERNOON AS THE LOW LEVEL JET EDGES EASTWARD. THIS HAS MADE THE SMALL CRAFT ADVISORY MARGINAL AT BEST BUT THE COLD FRONT IS JUST ABOUT TO REACH THE WESTERN END OF LAKE ERIE. AS WINDS SHIFT AROUND TO THE NORTHWEST IN THE WAKE OF THE FRONT WAVES SHOULD BEGIN TO BUILD BACK UP TO SMALL CRAFT LEVELS. THOUGHT ABOUT PULLING THE SMALL CRAFT BACK TO THE WEST WITH THIS UPDATE. HOWEVER WILL WAIT AND LATE THE NEXT SHIFT MONITOR HOW STRONG THE WINDS REALLY ARE IN THE WAKE OF THE FRONT. HIGH PRESSURE WILL MOVE QUICKLY ACROSS SOUTHERN ONTARIO AND INTO QUEBEC ON TUESDAY. THIS WILL ALLOW SOUTH TO SOUTHWEST WINDS TO RETURN FOR TUESDAY INTO TUESDAY NIGHT. ANOTHER COLD FRONT WILL CROSS LAKE ERIE BY WEDNESDAY AFTERNOON WITH ANOTHER SMALL CRAFT ADVISORY POSSIBLE EAST OF THE ISLANDS. HIGH PRESSURE WILL GAIN CONTROL OVER THE LAKE BY THURSDAY AFTERNOON WITH LIGHTER WINDS. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 9 PM EST MONDAY FOR LEZ147>149. SMALL CRAFT ADVISORY FROM 4 AM TO 9 PM EST MONDAY FOR LEZ145- 146. && $$ SYNOPSIS...OUDEMAN NEAR TERM...OUDEMAN SHORT TERM...OUDEMAN LONG TERM...MULLEN AVIATION...TK MARINE...TK/MULLEN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
910 PM EST SUN NOV 30 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE AREA TONIGHT. HIGH PRESSURE WILL BUILD ACROSS THE GREAT LAKES AND PASS NORTH OF OH/PA BETWEEN MONDAY AND TUESDAY. THE NEXT COLD FRONT CROSSES ON WEDNESDAY WITH HIGH PRESSURE BUILDING OVER THE LAKES ON THURSDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... THE DEFINED BAND OF SHRA ALONG THE COLD FRONT HAS NOW DROPPED SE THRU NW OH AND WILL SOON BE ALONG A CLE TO MNN LINE. WILL MAINTAIN THE PROGRESSION OF LIGHT RAIN CHANCES 50-70 PERCENT ACROSS THE AREA TONIGHT. MILD TEMPERATURES UNTIL THE FRONT PASSES. PRECIP WILL LIKELY EXIT BEFORE THE AIR GETS COLD ENOUGH FOR SNOW. TEMPERATURES BY 6 AM WILL BE IN THE 30S WITH A CONTINUED DROP INTO MID MONDAY MORNING. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/... HAVE REDUCED PRECIPITATION CHANCES ON MONDAY TO JUST A FEW FLURRIES FOR THE SNOWBELT. THE COLDER AIR IS SLOW TO SINK SOUTHWARD AND INVERSION REMAINS LOW. WILL STILL HAVE SOME LAKE CLOUDS AND AWAY FROM THE LAKE WILL LIKELY MAINTAIN SOME MID/HIGH CLOUDINESS WITH THE FRONTAL ZONE HANGING ACROSS THE OHIO VALLEY WITH ZONAL FLOW. TEMPERATURES WILL GO NO WHERE MONDAY AND WILL STAY IN THE LOWER AND MID 30S. THE COLDEST AIR WILL STAY REMOVED FROM OUR AREA AND BY TUESDAY WE BEGIN TO WARM SLIGHTLY WITH MOISTURE BEING DRAWN NORTHWARD AGAIN. TIMING FOR THE NEXT COLD FRONT IS FOR WEDNESDAY. AGAIN MOISTURE IS LIMITED AND MOST OF THE DYNAMICS PASS TO THE NORTH. KEPT THE LOW PRECIP CHANCES. && .LONG TERM /THURSDAY THROUGH SUNDAY/... HIGH PRESSURE WILL ACROSS SOUTHERN ONTARIO INTO QUEBEC BY THURSDAY NIGHT. THE MODELS THEN STRUGGLE ON THE TIMING OF THE NEXT PIECE OF JET ENERGY MOVING THROUGH THE SOUTHERN JET STREAM. CURRENT THINKING IS THAT MOS OF THE MOISTURE WILL REMAIN SOUTH OF THE OHIO RIVER VALLEY UNTIL THURSDAY NIGHT INTO FRIDAY. HOWEVER CONFIDENCE REMAINS LOW WITH THIS SCENARIO AND HAVE NOT GONE ANY HIGHER THAN CHANCE POPS FOR ANY PORTION OF THE COUNTY WARNING AREA. THURSDAY WILL BE THE COOLEST DAY OF THE LONG TERM WITH HIGHS REMAINING IN THE 30S. NEAR SEASONAL TEMPERATURES ARE ANTICIPATED THROUGH DAY 7. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... COLD FRONT ABOUT TO MOVE INTO KTOL THIS HOUR. MAINLY VFR AHEAD OF THE BOUNDARY WITH CONDITIONS DROPPING THROUGH MVFR TO IFR BEHIND. USING THE HRRR WIND SHIFT ATTEMPTED TO TIME FRONT ACROSS THE AREA REACHING KCLE BETWEEN 03-04Z AND KERI KCAK AND KYNG 04-05Z. EXPECT BRIEF MODERATE RAIN POSSIBLE WITH FRONT AS RADAR IS SHOWING 40 DBZ WITHIN THE FINE LINE. OTHERWISE MVFR TO IFR IN LIGHT RAIN DRIZZLE AND FOG BEHIND THE FRONT FOR THE OVERNIGHT AND INTO MONDAY MORNING BEFORE IMPROVING TO VFR DURING THE LATE MORNING AND AFTERNOON. .OUTLOOK...NON VFR POSSIBLE TUESDAY AFTERNOON THROUGH WEDNESDAY AND AGAIN FRIDAY. && .MARINE... WINDS HAVE STARTED TO DECREASE SLIGHTLY THIS AFTERNOON AS THE LOW LEVEL JET EDGES EASTWARD. THIS HAS MADE THE SMALL CRAFT ADVISORY MARGINAL AT BEST BUT THE COLD FRONT IS JUST ABOUT TO REACH THE WESTERN END OF LAKE ERIE. AS WINDS SHIFT AROUND TO THE NORTHWEST IN THE WAKE OF THE FRONT WAVES SHOULD BEGIN TO BUILD BACK UP TO SMALL CRAFT LEVELS. THOUGHT ABOUT PULLING THE SMALL CRAFT BACK TO THE WEST WITH THIS UPDATE. HOWEVER WILL WAIT AND LATE THE NEXT SHIFT MONITOR HOW STRONG THE WINDS REALLY ARE IN THE WAKE OF THE FRONT. HIGH PRESSURE WILL MOVE QUICKLY ACROSS SOUTHERN ONTARIO AND INTO QUEBEC ON TUESDAY. THIS WILL ALLOW SOUTH TO SOUTHWEST WINDS TO RETURN FOR TUESDAY INTO TUESDAY NIGHT. ANOTHER COLD FRONT WILL CROSS LAKE ERIE BY WEDNESDAY AFTERNOON WITH ANOTHER SMALL CRAFT ADVISORY POSSIBLE EAST OF THE ISLANDS. HIGH PRESSURE WILL GAIN CONTROL OVER THE LAKE BY THURSDAY AFTERNOON WITH LIGHTER WINDS. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 9 PM EST MONDAY FOR LEZ147>149. && $$ SYNOPSIS...OUDEMAN NEAR TERM...OUDEMAN/ADAMS SHORT TERM...OUDEMAN LONG TERM...MULLEN AVIATION...TK MARINE...MULLEN
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
729 PM EST SUN NOV 30 2014 .SYNOPSIS... A SHARP COLD FRONT WILL SAG THROUGH THE OHIO VALLEY TONIGHT. LIGHT RAIN WILL ACCOMPANY THIS FRONT FOR MOST LOCATIONS...AS WELL AS A TWENTY DEGREE TEMPERATURE DROP IN THE FIRST FEW HOURS AFTER IT PASSES. THE FRONT WILL SLOW A LITTLE ON ITS SOUTHWARD TREK ON MONDAY AS IT SAGS INTO VIRGINIA AND TENNESSEE...AND WEAK DISTURBANCES SHIFTING NORTHEAST ALONG THE FRONT MONDAY AFTERNOON AND EVENING WILL LINGER RAIN ACROSS PORTIONS OF SOUTHERN OHIO AND NORTHERN KENTUCKY. A LITTLE LIGHT SNOW MAY MIX IN ACROSS THIS AREA BEFORE PRECIPITATION ENDS MONDAY NIGHT. TEMPERATURES WILL BE MUCH COLDER ON MONDAY INTO TUESDAY...BEFORE THE FRONT RETURNS NORTHWARD BY MIDWEEK WITH MILD AIR AND A RETURNING THREAT FOR LIGHT RAIN SHOWERS. && .NEAR TERM /THROUGH MONDAY/... OVERLAYING YESTERDAY/S FORECAST SOUNDINGS VALID 30.12Z AT ILN WITH ILN RAOB AS VERIFICATION HAS SHOWN THAT NWP GUIDANCE HAS VASTLY OVERESTIMATED MIXING RATIOS/SATURATION BELOW 900MB LAST NIGHT THROUGH TODAY. THUS...DEPTH OF LOW LEVEL SATURATED LAYER HAS REMAINED ABOUT 1KM TO 1.2KM DEEP FROM LATE LAST NIGHT THROUGH MUCH OF THE DAY AND HAS KEPT DZ/RA-- PRODUCTION AT BAY THUS FAR. WOULD MUCH PREFER TO SEE THE SATURATED LAYER EXCEED 1.5KM AND CLOSER TO 2.0KM FOR A LOW LEVEL SATURATED LAYER TO PRODUCE -DZ/RA-- IN THE ABSENCE OF STRONGER LOW LEVEL SHORTWAVE TROUGH OR LOWER 100MB BOUNDARY LIKE WHAT WE HAVE IN THE OPEN WARM SECTOR TODAY. CLOUD CIGS REMAIN STUBBORNLY IN THE 2-3KFT LAYER AGL SO WE/VE BEEN PROGRESSIVELY DELAYING MEASURABLE RAIN THREATS. THIS HAS ALLOWED FOR EVEN WARMER READINGS /MANY LOCATIONS IN MID 60S/ AND DWPTS HAVE CHECKED IN ABOUT 5F-7F LOWER...STRUGGLING TO BREACH 50F...THUS T/TD SPREADS ARE > 10F MOST LOCATIONS. ALL THAT STARTING TO CHANGE HOWEVER AS SHARP/ARCTIC COLD FRONT APPROACHES AND GLANCING BLOW FROM PARENT HEIGHT FALLS SWEEPING ALONG THE US/CANADIAN BORDER IS FORCING A GRADUAL INCREASE IN SYNOPTIC ASCENT ACROSS THE GREAT LAKES. KIWX WSR-88D HAS RECENTLY DEPICTED BLOSSOMING ECHOES AHEAD OF THE COLD FRONT WHICH WAS DEPICTED AT 30.18Z TO RUN FROM GRAND RAPIDS /MI/ TO CHICAGO TO SPRINGFIELD /IL/. THE FURTHER SOUTH/WEST YOU TRAVEL ALONG THE FRONT IN IL/MO/OK...THE SHARPER THE TEMP GRADIENT /30F ACROSS ONE OR TWO COUNTIES IN SOME CASES/. HOWEVER...LACK OF BLOCKING IN THE FAST QUASI-ZONAL FLOW WILL KEEP THE ARCTIC POOL OF BITTERLY COLD AIR TRUCKING ON EAST /AND MODIFYING/ VS. SOUTHEAST AND THUS OUR LOCAL AREA BECOMES MORE AND MORE REMOVED FROM THE COLDEST AIR W/TIME. THUS...TEMP GRADIENT WILL SLOWLY RELAX ALONG THE FRONT IN THE NEXT 12 HOURS. WILL STILL BE AN IMPRESSIVE FRONT AS IT COMES THROUGH TONIGHT...WITH UP TO A 20 DEGREE TEMP DROP OVER 3-4 HOURS AND A RATHER ABRUPT WIND SHIFT TO THE NORTHWEST /WITH GUSTS/. HAVE FOLLOWED RAW 2M MODEL TEMP BLEND CLOSELY TO MITIGATE MINOR SPEED DIFFERENCES OF FRONTAL PASSAGE. THIS PUTS FRONT TO SCIOTO COUNTY /OH/ BY 12Z MONDAY..WITH TEMPS AT SUNRISE ON MONDAY LIKELY RANGING FROM NEAR OR JUST BELOW FREEZING /CELINA OH/ TO THE LOW TO MID 50S /PORTSMOUTH/. HAVE USED A BLEND OF NCEP HI-RES WINDOW GUIDANCE /ARW AND NMM CORES/ WITH SUBJECTIVE INTERPOLATION OF 30.17Z ESRL HRRR FOR TIMING OF RAIN WITH FRONTAL PASSAGE TONIGHT. THESE DATA SUGGEST WE WILL CONTINUE TO SEE SCT AREAS OF RAIN DEVELOP IMMEDIATELY AHEAD OF THE COLD FRONT AND A FINE LINE OF LIGHT RAIN DEVELOP ALONG/IMMEDIATELY BEHIND THE FRONT AND SWEEP THROUGH THE AREA PARTICULARLY AFTER 00Z. RECENT RADAR TRENDS TO OUR NW SUPPORT THIS REASONING. ALREADY SEEING SW-NE ORIENTED BANDS OF -DZ ACRS WCNTL OH NOW IN FRONT OF PRIMARY FINE LINE ALONG FRONT. KEEPING A 60-75% OF MEASURABLE RAIN AT MOST LOCATIONS WITH THE FRONTAL PASSAGE TONIGHT. AM PROBABLY TO LONG /DURATION/ WITH THREAT OF RAIN GIVEN DEPICTIONS IN SIMULATED REFLECTIVITY BUT TRIED TO KEEP RAIN TO NO MORE THAN 2-3 HOURS AT ANY ONE LOCATION. FRONT WILL BEGIN TO SLOW OVER KY TOMORROW AS IT SAGS SOUTH OF STRONGER/FASTER WESTERLY FLOW...BECOMING MORE PARALLEL THE DEEP LAYER FLOW. THIS SHOULD SERVE TO LINGER RAIN IN NORTHERN KY/FAR SOUTHERN OHIO /APPROX SOUTH OF CINCINNATI TO CHILLICOTHE LINE/ INTO THE AFTERNOON. LITTLE CONCERNED WITH THE 30.12Z RUNS OF GFS/ECMWF WHICH ENHANCE POST FRONTAL PCPN BANDS LATE MORNING/AFTN ALONG AND SOUTH OF AFOREMENTIONED LINE. QPF SEEMS LIGHT...BUT BOTH MODELS SUGGESTING 0.10 TO 0.20" QPF DEVELOPING IN RESPONSE TO MID LEVEL FRONTOGENESIS /FGEN/ SIGNAL THAT ACCOMPANIES BRIEF WINDOW OF RIGHT ENTRANCE ULJ FORCING THAT HAS WEAK SHORTWAVE/VORTICITY EMBEDDED IN THIS ANTICYCLONIC PORTION OF THE UPPER JET. THIS CAUSES CONCERN BECAUSE OF MARGINAL/CRITICAL THERMAL STRUCTURE OF THE BOUNDARY LAYER BY THE TIME...AS CAA WILL BE STRONG AND TEMPS/DWPTS WILL HAVE FALLEN/OR BE FALLING TO NEAR FREEZING...ESP ALONG OHIO RIVER. CLOSER INSPECTION OF 30.12Z LAYER MAX WET BULB TEMPS SUGGESTS 30.12Z ECMWF IS VERY BULLISH/FAST WITH THE CAA WHILE 30.12Z NAM/SREF MEAN THE SLOWEST...WITH 30.12Z GFS A MIDDLE OF THE ROAD SOLUTION. UNFORTUNATELY 30.12Z ECMWF IS ALSO MOST ROBUST WITH ITS LIGHT QPF DISTRIBUTION IN THE WAKE OF THE FRONT WITH THE STRONGEST CONTRIBUTION FROM THE UPPER JET - SO THIS PRESENTS A LOWER-END THREAT OF A PERIOD OF SNOW /VIA WET BULB PROCESSES AND CAA/ FOR PORTIONS OF NORTHERN KY AND/OR SRN OHIO MONDAY BEFORE PRECIPITATION WANES. HAVE NOT REALLY SEEN THIS THREAT ON PRIOR PARALLEL GFS...OPNL NAM...OR HIGHER RES GEM/HIRES-WINDOW RUNS...THESE PUSH FRONT FURTHER SOUTH AND THUS POST FRONTAL PCPN BANDS DEVELOP FURTHER SOUTH AND IN WARMER AIR /RAIN/. ALSO...COARSE 30.12Z ECMWF FORECAST SOUNDINGS /NOT NATIVE MODEL RES/ SUGGESTS MID LEVEL DRY AIR MAY INHIBIT MUCH PRECIP PRODUCTION AND PERHAPS HIGHER QPF DEPICTION FURTHER NORTH INTO COLD AIR A FUNCTION OF COARSE GRID RESOLUTION. SO MAIN CHANGE TO FORECAST WAS TO 1) LINGER HIGHER END RAIN CHANCES IN THE SOUTH ON MONDAY LATE MORNING AND AFTERNOON AND 2) ALLOW FOR THIS TO MIX WITH SNOW AS A START WITHOUT ANY ACCUMULATION. UPCOMING SHIFTS WILL NEED TO MONITOR FOR WHAT APPEARS TO BE A LOWER END/OUTLIER THREAT FOR A STRIPE OF LIGHT/WET ACCUMULATIONS IN OUR SOUTH ON MONDAY AFTN SHOULD A MORE ROBUST COLDER/WETTER ECMWF SCENARIO GARNER MORE NWP SUPPORT. && .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... BATCH OF MID LEVEL FGEN FORCING/WEAK VORT MAX AND RIGHT ENTRANCE REGION OF UPPER JET SHIFTS EAST LATER MONDAY NIGHT AND THUS EXPECT A PERIOD OF DRY CONDITIONS FROM MONDAY EVENING INTO TUESDAY AS 1045MB ARCTIC HIGH PRESSURE MOVES ACROSS SERN CANADA AND OUR SOURCE REGION AIRMASS EMANATES FROM THIS FEATURE ON NELY FLOW. A CHILLY MONDAY NIGHT IN THE MID 20S TO AROUND 30 BEFORE BACKING LOW AND MID LEVEL FLOW ALREADY STARTS TO ALLOW MIXING/EROSION OF THE VERY SHALLOW ARCTIC AIRMASS BY TUESDAY. AM ALLOWING MAX TEMPS ON TUESDAY BACK NEAR 40F BUT WAA WILL BE ONGOING ESPECIALLY JUST OFF THE SURFACE SO THESE READINGS COULD BE A LITTLE COOL GIVEN 925MB TEMPS BY MID AFTERNOON WILL BE 0C TO +5C ALREADY IN THE STRENGTHENING WAA REGIME. RATHER DECENT S/W TROUGH DIGGING THROUGH MN/WI TUESDAY NIGHT /INDUCING THE BACKING FLOW OVER THE OHIO VALLEY/ WILL ALLOW REMNANT MOISTURE/ISENTROPIC ASCENT OVER THE SHALLOW COLD DOME TO PERHAPS PRODUCE SOME LIGHT RAIN/DRIZZLE ESPECIALLY IN THE AREAS EAST OF I-71 TUESDAY NIGHT. BOUNDARY LAYER TEMPS SHOULD RISE THROUGH THE NIGHT...SO HAVE KEPT ANY POTENTIAL OF LIGHT FREEZING RAIN OUT OF THE FORECAST FOR TUESDAY NIGHT. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... OUR REGION WILL REMAIN UNDER THE INFLUENCE OF A PROGRESSIVE ZONAL FLOW PATTERN THROUGH AT LEAST THE END OF THE WORK WEEK...ALLOWING FOR MOISTURE TO CONTINUE TO STREAM IN FROM THE WEST/SOUTHWEST. AS IS TYPICAL IN A MORE PROGRESSIVE FLOW PATTERN...THE MODELS ARE STRUGGLING WITH THEIR TIMING AND PLACEMENT OF SEVERAL EMBEDDED SHORTWAVES. AS A RESULT...IT IS TOUGH TO RULE OUT A CHANCE OF RAIN WEDNESDAY THROUGH FRIDAY. THE MODELS DO SEEM TO BE TRENDING TOWARD THE BETTER MOISTURE/FORCING AFFECTING MORE OF OUR SOUTHERN FA THOUGH...SO WILL TREND POPS ACCORDINGLY WITH THE LOWEST POPS NORTHWEST AND THE HIGHEST IN THE SOUTHEAST. DUE TO THE TIMING ISSUES THOUGH...WILL KEEP POPS IN CHANCE CATEGORY OR LOWER. THE LOW LEVELS SHOULD REMAIN WARM ENOUGH TO SUPPORT PRIMARILY RAIN...BUT DEPENDING ON THE EXACT TIMING AND PLACEMENT...SOME SNOW COULD MIX IN ACROSS THE NORTH THURSDAY NIGHT INTO FRIDAY. TEMPERATURES SHOULD REMAIN FAIRLY SEASONABLE THROUGH FRIDAY...WITH HIGHS GENERALLY IN THE 40S AND OVERNIGHT LOWS MOSTLY IN THE 30S. THE MID LEVEL FLOW PATTERN WILL BEGIN TO AMPLIFY THROUGH THE WEEKEND WITH SOME MID LEVEL RIDGING DEVELOPING ACROSS THE OHIO VALLEY REGION. THIS WILL ALLOW FOR SOME DRYING THROUGH THE WEEKEND ALONG WITH SLIGHTLY WARMER TEMPERATURES. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... SFC FRONT JUST ENTERING NW OHIO WILL SWEEP SOUTH THRU THE TAF SITES TONIGHT. VFR CIGS WILL DROP TO MVFR AND THEN TO IFR UNTIL MONDAY MORNING. LIGHT RAIN WILL ACCOMPANY THE IFR CEILINGS. EXPECT IMPROVEMENT TO MVFR MONDAY MORNING AND THEN VFR DURG THE AFTN. SOUTHWEST WINDS GUSTING OVER 20 KNOTS WILL SHIFT TO NORTH WITH FRONTAL PASSAGE LATE TONIGHT. NORTH WINDS AT 10 TO 15 KTS WILL BECOME NORTHEAST BY MONDAY EVENING. OUTLOOK...MVFR CEILINGS POSSIBLE TUESDAY NIGHT INTO THURSDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...BINAU NEAR TERM...AR SHORT TERM...BINAU LONG TERM...JGL AVIATION...CONIGLIO
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
626 PM EST SUN NOV 30 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE AREA TONIGHT. HIGH PRESSURE WILL BUILD ACROSS THE GREAT LAKES AND PASS NORTH OF OH/PA BETWEEN MONDAY AND TUESDAY. THE NEXT COLD FRONT CROSSES ON WEDNESDAY WITH HIGH PRESSURE BUILDING OVER THE LAKES ON THURSDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... A MORE DEFINED BAND OF SHRA HAS NOW DEVELOPED ALONG THE COLD FRONT THAT IS ENTERING EXTREME NW LUCAS CO. WILL MAINTAIN THE PROGRESSION OF LIGHT RAIN CHANCES 50-70 PERCENT ACROSS THE AREA TONIGHT. MILD TEMPERATURES UNTIL THE FRONT PASSES. PRECIP WILL LIKELY EXIT BEFORE THE AIR GETS COLD ENOUGH FOR SNOW. TEMPERATURES BY 6 AM WILL BE IN THE 30S WITH A CONTINUED DROP INTO MONDAY MORNING. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/... HAVE REDUCED PRECIPITATION CHANCES ON MONDAY TO JUST A FEW FLURRIES FOR THE SNOWBELT. THE COLDER AIR IS SLOW TO SINK SOUTHWARD AND INVERSION REMAINS LOW. WILL STILL HAVE SOME LAKE CLOUDS AND AWAY FROM THE LAKE WILL LIKELY MAINTAIN SOME MID/HIGH CLOUDINESS WITH THE FRONTAL ZONE HANGING ACROSS THE OHIO VALLEY WITH ZONAL FLOW. TEMPERATURES WILL GO NO WHERE MONDAY AND WILL STAY IN THE LOWER AND MID 30S. THE COLDEST AIR WILL STAY REMOVED FROM OUR AREA AND BY TUESDAY WE BEGIN TO WARM SLIGHTLY WITH MOISTURE BEING DRAWN NORTHWARD AGAIN. TIMING FOR THE NEXT COLD FRONT IS FOR WEDNESDAY. AGAIN MOISTURE IS LIMITED AND MOST OF THE DYNAMICS PASS TO THE NORTH. KEPT THE LOW PRECIP CHANCES. && .LONG TERM /THURSDAY THROUGH SUNDAY/... HIGH PRESSURE WILL ACROSS SOUTHERN ONTARIO INTO QUEBEC BY THURSDAY NIGHT. THE MODELS THEN STRUGGLE ON THE TIMING OF THE NEXT PIECE OF JET ENERGY MOVING THROUGH THE SOUTHERN JET STREAM. CURRENT THINKING IS THAT MOS OF THE MOISTURE WILL REMAIN SOUTH OF THE OHIO RIVER VALLEY UNTIL THURSDAY NIGHT INTO FRIDAY. HOWEVER CONFIDENCE REMAINS LOW WITH THIS SCENARIO AND HAVE NOT GONE ANY HIGHER THAN CHANCE POPS FOR ANY PORTION OF THE COUNTY WARNING AREA. THURSDAY WILL BE THE COOLEST DAY OF THE LONG TERM WITH HIGHS REMAINING IN THE 30S. NEAR SEASONAL TEMPERATURES ARE ANTICIPATED THROUGH DAY 7. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... COLD FRONT ABOUT TO MOVE INTO KTOL THIS HOUR. MAINLY VFR AHEAD OF THE BOUNDARY WITH CONDITIONS DROPPING THROUGH MVFR TO IFR BEHIND. USING THE HRRR WIND SHIFT ATTEMPTED TO TIME FRONT ACROSS THE AREA REACHING KCLE BETWEEN 03-04Z AND KERI KCAK AND KYNG 04-05Z. EXPECT BRIEF MODERATE RAIN POSSIBLE WITH FRONT AS RADAR IS SHOWING 40 DBZ WITHIN THE FINE LINE. OTHERWISE MVFR TO IFR IN LIGHT RAIN DRIZZLE AND FOG BEHIND THE FRONT FOR THE OVERNIGHT AND INTO MONDAY MORNING BEFORE IMPROVING TO VFR DURING THE LATE MORNING AND AFTERNOON. .OUTLOOK...NON VFR POSSIBLE TUESDAY AFTERNOON THROUGH WEDNESDAY AND AGAIN FRIDAY. && .MARINE... WINDS HAVE STARTED TO DECREASE SLIGHTLY THIS AFTERNOON AS THE LOW LEVEL JET EDGES EASTWARD. THIS HAS MADE THE SMALL CRAFT ADVISORY MARGINAL AT BEST BUT THE COLD FRONT IS JUST ABOUT TO REACH THE WESTERN END OF LAKE ERIE. AS WINDS SHIFT AROUND TO THE NORTHWEST IN THE WAKE OF THE FRONT WAVES SHOULD BEGIN TO BUILD BACK UP TO SMALL CRAFT LEVELS. THOUGHT ABOUT PULLING THE SMALL CRAFT BACK TO THE WEST WITH THIS UPDATE. HOWEVER WILL WAIT AND LATE THE NEXT SHIFT MONITOR HOW STRONG THE WINDS REALLY ARE IN THE WAKE OF THE FRONT. HIGH PRESSURE WILL MOVE QUICKLY ACROSS SOUTHERN ONTARIO AND INTO QUEBEC ON TUESDAY. THIS WILL ALLOW SOUTH TO SOUTHWEST WINDS TO RETURN FOR TUESDAY INTO TUESDAY NIGHT. ANOTHER COLD FRONT WILL CROSS LAKE ERIE BY WEDNESDAY AFTERNOON WITH ANOTHER SMALL CRAFT ADVISORY POSSIBLE EAST OF THE ISLANDS. HIGH PRESSURE WILL GAIN CONTROL OVER THE LAKE BY THURSDAY AFTERNOON WITH LIGHTER WINDS. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 9 PM EST MONDAY FOR LEZ147>149. && $$ SYNOPSIS...OUDEMAN NEAR TERM...OUDEMAN SHORT TERM...OUDEMAN LONG TERM...MULLEN AVIATION...TK MARINE...MULLEN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1051 PM EST SUN NOV 30 2014 .SYNOPSIS... HIGH PRESSURE WILL REMAIN ACROSS THE REGION THROUGH MONDAY BEFORE A COLD FRONT CROSSES FROM THE NORTH EARLY TUESDAY. A COLD WEDGE OF HIGH PRESSURE BUILDS IN TUESDAY WITH WEAK HIGH PRESSURE REMAINING OVER THE AREA THROUGH THURSDAY. && .NEAR TERM /THROUGH MONDAY/... 1030 PM EST UPDATE...THE LATEST 18Z MODELS CONTINUE TO AGREE THAT A COLD FRONT CURRENTLY EXTENDING FROM THE OHIO VALLEY TO THE WESTERN GULF WILL MOVE SEWARD INTO THE TN VALLEY BY MON AFTERNOON AND REACHES THE APPALACHIANS BY AROUND 6Z TUE...WHILE SURFACE RIDGE OVER THE SE WEAKENS AND SLOWLY SHIFT EAST. THEREFORE...CONDITIONS APPEAR TO REMAIN MOSTLY DRY DURING THE OVERNIGHT HOURS AND INTO TUE...WITH LLVL CLOUDS OVERSPREADING THE REGION TUE AFTERNOON INTO TUE NIGHT. WITH GOOD LLVL INVERSION UNDERNEATH MOIST SWLY FLOW ALOFT...PATCHY FOG WILL DEVELOP MAINLY ACROSS THE WESTERN ZONES OF THE MTNS/VALLEYS AND PORTIONS OF THE WESTERN UPSTATE SC. OTHERWISE...FAIRLY QUIET CONDITIONS WITH ABOVE NORMAL TEMPS SHOULD CONTINUE THROUGH TUE. 750 PM EST UPDATE...THE CURRENT FCST APPEARS TO BE ON TRACK. HENCE...NO CHANGES WERE NEEDED ATT. 430 PM EST UPDATE...HAVE MADE MINOR ADJUSTMENTS TO WINDS/HOURLY TEMPS PER LATEST OBS TREND AND GUIDANCE. OTHERWISE...THE CURRENT FORECAST IS ON TRACK. AS OF 210 PM...UPPER RIDGE AXIS MOVES EAST OF THE AREA TONIGHT AS SFC HIGH PRESSURE REMAINS RIDGED INTO THE AREA FROM THE EAST AND A COLD FRONT MOVES INTO THE TN VALLEY. GUIDANCE IS CONFLICTED AND INCONSISTENT ON THE RESULT OF THE LOW LEVEL MOISTURE REMAINING ACROSS THE AREA TONIGHT. THERE COULD BE A RETURN OF LOW CLOUDS LIKE THIS MORNING...OR THERE COULD BE AREAS OF DENSE FOG. GIVEN THE LOW CONFIDENCE...HAVE GONE WITH CLOUDS AND ONLY PATCHY LIGHT FOG. LOWS WILL BE 5 TO 10 DEGREES ABOVE NORMAL WITH ANOTHER NITE OF INVERSE LAPSE RATES ACROSS THE MTNS. UPPER TROF MOVES TOWARD THE AREA MON PUSHING THE COLD FRONT ACROSS THE AREA. THE FRONT IS AN ANAFRONT WITH THE BULK OF THE DEEP MOISTURE...FORCING AND PRECIP REMAINING TO OUR WEST. HAVE ONLY A SMALL CHC OF PRECIP MOVING INTO THE TN BORDER COUNTIES THRU THE DAY. THICKNESSES INCREASE AND CLOUD COVER REMAINS LIMITED...RESULTING IN ANOTHER DAY WITH HIGHS AROUND 10 DEGREES ABOVE NORMAL. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... AS OF 130 PM EST SUNDAY...THE PRIMARY FOCUS OF THE SHORT TERM CONTINUES TO BE THE DEVELOPING CAD WEDGE ON TUESDAY AND ASSOCIATED UPGLIDE PRECIP ACROSS THE REGION. THE FCST INITIALIZES MONDAY EVENING WITH MODEL CONSENSUS ON AN EASTWARD PROPAGATING UPPER TROF ACROSS THE EAST/CENTRAL CONUS. AT THE SURFACE...HIGH PRESSURE ALONG THE SOUTHEAST COASTLINE WILL SLOWLY WEAKEN AS PRESSURES FALL FROM THE WEST AS A COLD FRONT SLIDES INTO THE TN VALLEY. BROAD 1045MB HIGH PRESSURE RIDGE WILL ADVECT EAST THROUGH THE GREAT LAKES LEADING TO CAD WEDGE DEVELOPMENT INTO TUESDAY. POPS WILL INCREASE FROM THE WEST ALONG THE TN LINE ASSOCIATED WITH THE FRONTAL INTRUSION MONDAY NIGHT...BEFORE INCREASING TO LIKELY LEVELS FURTHER EAST ALONG THE BLUE RIDGE ON TUESDAY AS THE ABOVE MENTIONED WEDGE INTRUDES LEADING TO ENHANCED UPGLIDE. ELSEWHERE...POPS INCREASE TO LOW END CHANCE LEVELS THROUGH TUESDAY FOR THE VAST MAJORITY OF THE FCST AREA WITH THE HIGHEST POPS RESIDING ALONG THE ESCARPMENT. FORTUNATELY THE PARENT HIGH MOVING THROUGH THE NORTHEAST WITH REMAIN PROGRESSIVE THEREBY LIMITING THE DEPTH/LONGEVITY OF THE WEDGE. MODELS CONTINUE TO AGREE ON WEDGE EROSION THROUGH TUESDAY NIGHT INTO WEDNESDAY MORNING WITH LOW LEVEL THICKNESSES RISING. THUS THE FCST ONCE AGAIN FEATURES ALL LIQUID PRECIP WITH PROFILES NOT BEING SUPPORTIVE OF ANY WINTRY PTYPES. MEANWHILE...THE OLD FRONTAL AXIS WILL CONTINUE TO MEANDER OVER THE WESTERN SLOPES OF THE SOUTHERN/CENTRAL APPS WARRANTING CONTINUED POPS THROUGH MUCH OF THE DAY ON WEDNESDAY WITH ALL OTHER LOWER ELEVATION SITES REMAINING DRY. TEMPERATURES THROUGH THE PERIOD WILL COOL TO BELOW NORMAL LEVELS BEHIND THE CAD BOUNDARY ON TUESDAY WITH A GRADUAL WARMING TREND TO FOLLOW WITH NEAR NORMAL TEMPERATURES FEATURED BY WEDNESDAY AFTERNOON. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 1245 PM SUNDAY...IT STILL LOOKS LIKE FLAT FLOW ALOFT WILL BE ATOP THE SE CONUS TO START OFF THE PERIOD WITH SW LLVL FLOW ALLOWING MAXIMUM TEMPERATURES TO RISE TO ABOVE THE EARLY DECEMBER NORMAL. REGIONALLY...THE BETTER SHOWER CHANCES WILL BE LOCATED NORTH AND WEST OF THE CWFA CLOSER TO STALLED BAROCLINIC ZONE. THE MEDIUM RANGE MODEL CONSENSUS DEVELOPS EAST COAST SFC RIDGE INTO A DAMMING CONFIGURATION FRIDAY INTO SATURDAY. WITH THE PARENT HIPRES LOOKING TO BE PROGRESSIVE AND WHAT MAY WIND UP BEING JUST WEAK FORCING...WILL COOL MAX TEMPERATURES ONLY MARGINALLY...REMAINING WITHIN A CATEGORY OF CLIMO AND PCPN CHANCES JUST TOKEN CHANCE. && .AVIATION /04Z MONDAY THROUGH FRIDAY/... AT KCLT...VFR EXPECTED THROUGH THE TAF PERIOD...AS HIGH PRESSURE CENTERED OVER THE WESTERN ATLANTIC CONTINUES TO RIDGE INTO THE REGION...YIELDING DRY WEATHER AND PREVAILING WARM AIR ADVECTION SWLY FLOW. AS FOR THE FOG POTENTIAL ON EARLY MON MORNING...MODEL CONSENSUS SUGGESTS NO FOG THOUGH THE RAP SOUNDING DEPICTS SOME BRIEF MVFR FOG BEFORE SUNRISE. HOWEVER...WITH LOW CONFIDENCE...HAVE DECIDED NOT TO MENTION ANY FOG AT THIS TIME. AS A COLD FRONT APPROACHES THE APPALACHIANS FROM THE NW THROUGH MON EVENING...LVFR CLOUDS WILL OVERSPREAD THE AREA BY MON AFTERNOON. ELSEWHERE...EXPECT VFR CONDITIONS TO CONTINUE THROUGH 00Z AS HIGH PRESSURE OVER WESTERN ATLANTIC CONTINUES TO RIDGE WESTWARD INTO OUR AREA. THE EXCEPTION WILL BE KAND AND KAVL WHERE BRIEF PERIODS OF MVFR CIGS/VSBY COULD DEVELOP BEFORE SUNRISE ON MONDAY PER LATEST GUIDANCE. DUE TO THE TERRAIN EFFECT...WINDS AT KAVL WILL REMAIN SOUTHERLY THROUGH THE OVERNIGHT HOURS...BEFORE VEERING TO THE NORTH BY MON MORNING. N WINDS WILL THEN VEER BACK TO THE SOUTH BY MON AFTERNOON IN RESPONSE TO AN APPROACHING COLD FRONT FROM THE NORTHWEST. ELSEWHERE WILL SEE PREVAILING SW WINDS THROUGH THE PERIOD. OUTLOOK...A COLD FRONT WILL SLOWLY SLIP SOUTH ACROSS THE SOUTHERN APPALACHIANS ON MONDAY NIGHT. ON TUESDAY...A STRONG RIDGE OF HIGH PRESSURE WILL BUILD ACROSS THE REGION FROM THE NORTH WITH INCREASING LOW LEVEL MOISTURE...LIKELY RESULTING IN WIDESPREAD CEILING RESTRICTIONS THROUGH MID WEEK AS A COLD AIR DAMMING WEDGE DEVELOPS. CONFIDENCE TABLE... 04-10Z 10-16Z 16-22Z 22-00Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...SBK NEAR TERM...JOH/RWH SHORT TERM...CDG LONG TERM...CSH AVIATION...JOH
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
801 PM EST SUN NOV 30 2014 .SYNOPSIS... HIGH PRESSURE WILL REMAIN ACROSS THE REGION THROUGH MONDAY BEFORE A COLD FRONT CROSSES FROM THE NORTH EARLY TUESDAY. A COLD WEDGE OF HIGH PRESSURE BUILDS IN TUESDAY WITH WEAK HIGH PRESSURE REMAINING OVER THE AREA THROUGH THURSDAY. && .NEAR TERM /THROUGH MONDAY/... 750 PM EST UPDATE...THE CURRENT FCST APPEARS TO BE ON TRACK. HENCE...NO CHANGES WERE NEEDED ATT. 430 PM EST UPDATE...HAVE MADE MINOR ADJUSTMENTS TO WINDS/HOURLY TEMPS PER LATEST OBS TREND AND GUIDANCE. OTHERWISE...THE CURRENT FORECAST IS ON TRACK. AS OF 210 PM...UPPER RIDGE AXIS MOVES EAST OF THE AREA TONIGHT AS SFC HIGH PRESSURE REMAINS RIDGED INTO THE AREA FROM THE EAST AND A COLD FRONT MOVES INTO THE TN VALLEY. GUIDANCE IS CONFLICTED AND INCONSISTENT ON THE RESULT OF THE LOW LEVEL MOISTURE REMAINING ACROSS THE AREA TONIGHT. THERE COULD BE A RETURN OF LOW CLOUDS LIKE THIS MORNING...OR THERE COULD BE AREAS OF DENSE FOG. GIVEN THE LOW CONFIDENCE...HAVE GONE WITH CLOUDS AND ONLY PATCHY LIGHT FOG. LOWS WILL BE 5 TO 10 DEGREES ABOVE NORMAL WITH ANOTHER NITE OF INVERSE LAPSE RATES ACROSS THE MTNS. UPPER TROF MOVES TOWARD THE AREA MON PUSHING THE COLD FRONT ACROSS THE AREA. THE FRONT IS AN ANAFRONT WITH THE BULK OF THE DEEP MOISTURE...FORCING AND PRECIP REMAINING TO OUR WEST. HAVE ONLY A SMALL CHC OF PRECIP MOVING INTO THE TN BORDER COUNTIES THRU THE DAY. THICKNESSES INCREASE AND CLOUD COVER REMAINS LIMITED...RESULTING IN ANOTHER DAY WITH HIGHS AROUND 10 DEGREES ABOVE NORMAL. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... AS OF 130 PM EST SUNDAY...THE PRIMARY FOCUS OF THE SHORT TERM CONTINUES TO BE THE DEVELOPING CAD WEDGE ON TUESDAY AND ASSOCIATED UPGLIDE PRECIP ACROSS THE REGION. THE FCST INITIALIZES MONDAY EVENING WITH MODEL CONSENSUS ON AN EASTWARD PROPAGATING UPPER TROF ACROSS THE EAST/CENTRAL CONUS. AT THE SURFACE...HIGH PRESSURE ALONG THE SOUTHEAST COASTLINE WILL SLOWLY WEAKEN AS PRESSURES FALL FROM THE WEST AS A COLD FRONT SLIDES INTO THE TN VALLEY. BROAD 1045MB HIGH PRESSURE RIDGE WILL ADVECT EAST THROUGH THE GREAT LAKES LEADING TO CAD WEDGE DEVELOPMENT INTO TUESDAY. POPS WILL INCREASE FROM THE WEST ALONG THE TN LINE ASSOCIATED WITH THE FRONTAL INTRUSION MONDAY NIGHT...BEFORE INCREASING TO LIKELY LEVELS FURTHER EAST ALONG THE BLUE RIDGE ON TUESDAY AS THE ABOVE MENTIONED WEDGE INTRUDES LEADING TO ENHANCED UPGLIDE. ELSEWHERE...POPS INCREASE TO LOW END CHANCE LEVELS THROUGH TUESDAY FOR THE VAST MAJORITY OF THE FCST AREA WITH THE HIGHEST POPS RESIDING ALONG THE ESCARPMENT. FORTUNATELY THE PARENT HIGH MOVING THROUGH THE NORTHEAST WITH REMAIN PROGRESSIVE THEREBY LIMITING THE DEPTH/LONGEVITY OF THE WEDGE. MODELS CONTINUE TO AGREE ON WEDGE EROSION THROUGH TUESDAY NIGHT INTO WEDNESDAY MORNING WITH LOW LEVEL THICKNESSES RISING. THUS THE FCST ONCE AGAIN FEATURES ALL LIQUID PRECIP WITH PROFILES NOT BEING SUPPORTIVE OF ANY WINTRY PTYPES. MEANWHILE...THE OLD FRONTAL AXIS WILL CONTINUE TO MEANDER OVER THE WESTERN SLOPES OF THE SOUTHERN/CENTRAL APPS WARRANTING CONTINUED POPS THROUGH MUCH OF THE DAY ON WEDNESDAY WITH ALL OTHER LOWER ELEVATION SITES REMAINING DRY. TEMPERATURES THROUGH THE PERIOD WILL COOL TO BELOW NORMAL LEVELS BEHIND THE CAD BOUNDARY ON TUESDAY WITH A GRADUAL WARMING TREND TO FOLLOW WITH NEAR NORMAL TEMPERATURES FEATURED BY WEDNESDAY AFTERNOON. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 1245 PM SUNDAY...IT STILL LOOKS LIKE FLAT FLOW ALOFT WILL BE ATOP THE SE CONUS TO START OFF THE PERIOD WITH SW LLVL FLOW ALLOWING MAXIMUM TEMPERATURES TO RISE TO ABOVE THE EARLY DECEMBER NORMAL. REGIONALLY...THE BETTER SHOWER CHANCES WILL BE LOCATED NORTH AND WEST OF THE CWFA CLOSER TO STALLED BAROCLINIC ZONE. THE MEDIUM RANGE MODEL CONSENSUS DEVELOPS EAST COAST SFC RIDGE INTO A DAMMING CONFIGURATION FRIDAY INTO SATURDAY. WITH THE PARENT HIPRES LOOKING TO BE PROGRESSIVE AND WHAT MAY WIND UP BEING JUST WEAK FORCING...WILL COOL MAX TEMPERATURES ONLY MARGINALLY...REMAINING WITHIN A CATEGORY OF CLIMO AND PCPN CHANCES JUST TOKEN CHANCE. && .AVIATION /01Z MONDAY THROUGH FRIDAY/... AT KCLT...VFR EXPECTED THROUGH THE TAF PERIOD...AS HIGH PRESSURE CENTERED OVER THE WESTERN ATLANTIC CONTINUES TO RIDGE INTO THE REGION...YIELDING DRY WEATHER AND PREVAILING WARM AIR ADVECTION SWLY FLOW. AS FOR THE FOG POTENTIAL ON EARLY MON MORNING...MODEL CONSENSUS SUGGESTS NO FOG THOUGH THE RAP SOUNDING DEPICTS SOME BRIEF MVFR FOG BEFORE SUNRISE. HOWEVER...WITH LOW CONFIDENCE...HAVE DECIDED NOT TO MENTION ANY FOG AT THIS TIME. AS A COLD FRONT APPROACHES THE APPALACHIANS FROM THE NW THROUGH MON EVENING...LVFR CLOUDS WILL OVERSPREAD THE AREA BY MON AFTERNOON. ELSEWHERE...EXPECT VFR CONDITIONS TO CONTINUE THROUGH 00Z AS HIGH PRESSURE OVER WESTERN ATLANTIC CONTINUES TO RIDGE WESTWARD INTO OUR AREA. THE EXCEPTION WILL BE KAND AND KAVL WHERE BRIEF PERIODS OF MVFR CIGS/VSBY COULD DEVELOP BEFORE SUNRISE ON MONDAY PER LATEST GUIDANCE. DUE TO THE TERRAIN EFFECT...WINDS AT KAVL WILL REMAIN SOUTHERLY THROUGH THE OVERNIGHT HOURS...BEFORE VEERING TO THE NORTH BY MON MORNING. N WINDS WILL THEN VEER BACK TO THE SOUTH BY MON AFTERNOON IN RESPONSE TO AN APPROACHING COLD FRONT FROM THE NORTHWEST. ELSEWHERE WILL SEE PREVAILING SW WINDS THROUGH THE PERIOD. OUTLOOK...A COLD FRONT WILL SLOWLY SLIP SOUTH ACROSS THE SOUTHERN APPALACHIANS ON MONDAY NIGHT. ON TUESDAY...A STRONG RIDGE OF HIGH PRESSURE WILL BUILD ACROSS THE REGION FROM THE NORTH WITH INCREASING LOW LEVEL MOISTURE...LIKELY RESULTING IN WIDESPREAD CEILING RESTRICTIONS THROUGH MID WEEK AS A COLD AIR DAMMING WEDGE DEVELOPS. CONFIDENCE TABLE... 01-07Z 07-13Z 13-19Z 19-00Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 88% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...SBK NEAR TERM...JOH/RWH SHORT TERM...CDG LONG TERM...CSH AVIATION...JOH
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
704 PM EST SUN NOV 30 2014 .SYNOPSIS... HIGH PRESSURE WILL REMAIN ACROSS THE REGION THROUGH MONDAY BEFORE A COLD FRONT CROSSES FROM THE NORTH EARLY TUESDAY. A COLD WEDGE OF HIGH PRESSURE BUILDS IN TUESDAY WITH WEAK HIGH PRESSURE REMAINING OVER THE AREA THROUGH THURSDAY. && .NEAR TERM /THROUGH MONDAY/... 430 PM EST UPDATE...HAVE MADE MINOR ADJUSTMENTS TO WINDS/HOURLY TEMPS PER LATEST OBS TREND AND GUIDANCE. OTHERWISE...THE CURRENT FORECAST IS ON TRACK. AS OF 210 PM...UPPER RIDGE AXIS MOVES EAST OF THE AREA TONIGHT AS SFC HIGH PRESSURE REMAINS RIDGED INTO THE AREA FROM THE EAST AND A COLD FRONT MOVES INTO THE TN VALLEY. GUIDANCE IS CONFLICTED AND INCONSISTENT ON THE RESULT OF THE LOW LEVEL MOISTURE REMAINING ACROSS THE AREA TONIGHT. THERE COULD BE A RETURN OF LOW CLOUDS LIKE THIS MORNING...OR THERE COULD BE AREAS OF DENSE FOG. GIVEN THE LOW CONFIDENCE...HAVE GONE WITH CLOUDS AND ONLY PATCHY LIGHT FOG. LOWS WILL BE 5 TO 10 DEGREES ABOVE NORMAL WITH ANOTHER NITE OF INVERSE LAPSE RATES ACROSS THE MTNS. UPPER TROF MOVES TOWARD THE AREA MON PUSHING THE COLD FRONT ACROSS THE AREA. THE FRONT IS AN ANAFRONT WITH THE BULK OF THE DEEP MOISTURE...FORCING AND PRECIP REMAINING TO OUR WEST. HAVE ONLY A SMALL CHC OF PRECIP MOVING INTO THE TN BORDER COUNTIES THRU THE DAY. THICKNESSES INCREASE AND CLOUD COVER REMAINS LIMITED...RESULTING IN ANOTHER DAY WITH HIGHS AROUND 10 DEGREES ABOVE NORMAL. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... AS OF 130 PM EST SUNDAY...THE PRIMARY FOCUS OF THE SHORT TERM CONTINUES TO BE THE DEVELOPING CAD WEDGE ON TUESDAY AND ASSOCIATED UPGLIDE PRECIP ACROSS THE REGION. THE FCST INITIALIZES MONDAY EVENING WITH MODEL CONSENSUS ON AN EASTWARD PROPAGATING UPPER TROF ACROSS THE EAST/CENTRAL CONUS. AT THE SURFACE...HIGH PRESSURE ALONG THE SOUTHEAST COASTLINE WILL SLOWLY WEAKEN AS PRESSURES FALL FROM THE WEST AS A COLD FRONT SLIDES INTO THE TN VALLEY. BROAD 1045MB HIGH PRESSURE RIDGE WILL ADVECT EAST THROUGH THE GREAT LAKES LEADING TO CAD WEDGE DEVELOPMENT INTO TUESDAY. POPS WILL INCREASE FROM THE WEST ALONG THE TN LINE ASSOCIATED WITH THE FRONTAL INTRUSION MONDAY NIGHT...BEFORE INCREASING TO LIKELY LEVELS FURTHER EAST ALONG THE BLUE RIDGE ON TUESDAY AS THE ABOVE MENTIONED WEDGE INTRUDES LEADING TO ENHANCED UPGLIDE. ELSEWHERE...POPS INCREASE TO LOW END CHANCE LEVELS THROUGH TUESDAY FOR THE VAST MAJORITY OF THE FCST AREA WITH THE HIGHEST POPS RESIDING ALONG THE ESCARPMENT. FORTUNATELY THE PARENT HIGH MOVING THROUGH THE NORTHEAST WITH REMAIN PROGRESSIVE THEREBY LIMITING THE DEPTH/LONGEVITY OF THE WEDGE. MODELS CONTINUE TO AGREE ON WEDGE EROSION THROUGH TUESDAY NIGHT INTO WEDNESDAY MORNING WITH LOW LEVEL THICKNESSES RISING. THUS THE FCST ONCE AGAIN FEATURES ALL LIQUID PRECIP WITH PROFILES NOT BEING SUPPORTIVE OF ANY WINTRY PTYPES. MEANWHILE...THE OLD FRONTAL AXIS WILL CONTINUE TO MEANDER OVER THE WESTERN SLOPES OF THE SOUTHERN/CENTRAL APPS WARRANTING CONTINUED POPS THROUGH MUCH OF THE DAY ON WEDNESDAY WITH ALL OTHER LOWER ELEVATION SITES REMAINING DRY. TEMPERATURES THROUGH THE PERIOD WILL COOL TO BELOW NORMAL LEVELS BEHIND THE CAD BOUNDARY ON TUESDAY WITH A GRADUAL WARMING TREND TO FOLLOW WITH NEAR NORMAL TEMPERATURES FEATURED BY WEDNESDAY AFTERNOON. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 1245 PM SUNDAY...IT STILL LOOKS LIKE FLAT FLOW ALOFT WILL BE ATOP THE SE CONUS TO START OFF THE PERIOD WITH SW LLVL FLOW ALLOWING MAXIMUM TEMPERATURES TO RISE TO ABOVE THE EARLY DECEMBER NORMAL. REGIONALLY...THE BETTER SHOWER CHANCES WILL BE LOCATED NORTH AND WEST OF THE CWFA CLOSER TO STALLED BAROCLINIC ZONE. THE MEDIUM RANGE MODEL CONSENSUS DEVELOPS EAST COAST SFC RIDGE INTO A DAMMING CONFIGURATION FRIDAY INTO SATURDAY. WITH THE PARENT HIPRES LOOKING TO BE PROGRESSIVE AND WHAT MAY WIND UP BEING JUST WEAK FORCING...WILL COOL MAX TEMPERATURES ONLY MARGINALLY...REMAINING WITHIN A CATEGORY OF CLIMO AND PCPN CHANCES JUST TOKEN CHANCE. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... AT KCLT...VFR EXPECTED THROUGH THE TAF PERIOD...AS HIGH PRESSURE CENTERED OVER THE WESTERN ATLANTIC CONTINUES TO RIDGE INTO THE REGION...YIELDING DRY WEATHER AND PREVAILING WARM AIR ADVECTION SWLY FLOW. AS FOR THE FOG POTENTIAL ON EARLY MON MORNING...MODEL CONSENSUS SUGGESTS NO FOG THOUGH THE RAP SOUNDING DEPICTS SOME BRIEF MVFR FOG BEFORE SUNRISE. HOWEVER...WITH LOW CONFIDENCE...HAVE DECIDED NOT TO MENTION ANY FOG AT THIS TIME. AS A COLD FRONT APPROACHES THE APPALACHIANS FROM THE NW THROUGH MON EVENING...LVFR CLOUDS WILL OVERSPREAD THE AREA BY MON AFTERNOON. ELSEWHERE...EXPECT VFR CONDITIONS TO CONTINUE THROUGH 00Z AS HIGH PRESSURE OVER WESTERN ATLANTIC CONTINUES TO RIDGE WESTWARD INTO OUR AREA. THE EXCEPTION WILL BE KAND AND KAVL WHERE BRIEF PERIODS OF MVFR CIGS/VSBY COULD DEVELOP BEFORE SUNRISE ON MONDAY PER LATEST GUIDANCE. DUE TO THE TERRAIN EFFECT...WINDS AT KAVL WILL REMAIN SOUTHERLY THROUGH THE OVERNIGHT HOURS...BEFORE VEERING TO THE NORTH BY MON MORNING. N WINDS WILL THEN VEER BACK TO THE SOUTH BY MON AFTERNOON IN RESPONSE TO AN APPROACHING COLD FRONT FROM THE NORTHWEST. ELSEWHERE WILL SEE PREVAILING SW WINDS THROUGH THE PERIOD. OUTLOOK...A COLD FRONT WILL SLOWLY SLIP SOUTH ACROSS THE SOUTHERN APPALACHIANS ON MONDAY NIGHT. ON TUESDAY...A STRONG RIDGE OF HIGH PRESSURE WILL BUILD ACROSS THE REGION FROM THE NORTH WITH INCREASING LOW LEVEL MOISTURE...LIKELY RESULTING IN WIDESPREAD CEILING RESTRICTIONS THROUGH MID WEEK AS A COLD AIR DAMMING WEDGE DEVELOPS. CONFIDENCE TABLE... 00-06Z 06-12Z 12-18Z 18-00Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 98% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 86% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...SBK NEAR TERM...JOH/RWH SHORT TERM...CDG LONG TERM...CSH AVIATION...JOH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1039 PM CST FRI NOV 28 2014 .UPDATE... ISSUED AT 947 PM CST FRI NOV 28 2014 VISIBILITIES ACROSS THE EASTERN PORTIONS OF THE FORECAST AREA FLOUNDERING IN THE 4-7 RANGE OVER THE LAST FEW HOURS. IN ADDITION...STRATUS HAS DEVELOPED JUST TO THE NORTH OF THE FORECAST AREA AND HAS SPILLED INTO LINCOLN AND BROOKINGS COUNTY. THINK THE INCREASING CLOUDS WILL MAKE IT INCREASINGLY DIFFICULT FOR DENSE FOG TO DEVELOP...AND HAVE DROPPED FOG MENTION BACK TO PATCHY. UPDATE POSTED. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 231 PM CST FRI NOV 28 2014 MAIN QUESTION TONIGHT IS FOG POTENTIAL OR NOT. THE NAM AND RAP CONTINUE TO SHOW A LOT OF FOG DEVELOPMENT THROUGHOUT MUCH OF NORTHWEST IA...SOUTHWEST MN...PARTS OF SOUTHEAST SD AND EAST CENTRAL SD. THEY BEGIN THE FOG DEVELOPMENT THIS EVENING ACROSS FAR NORTHWEST IA...THEN EXPAND IT WEST AND NORTHWARD. THE NAM AND RAP ARE VERY MOIST WITH THEIR RESPECTIVE SURFACE DEW POINT DEPRESSIONS...IN FACT SHOWING A LOT OF 1 TO 2 DEGREE DEW POINT DEPRESSION SPREADS EVEN AT THIS TIME WHICH IS NOT VERIFYING. THE GFS...ECMWF AND ARW ARE MUCH MORE SUBDUED...SHOWING WIDER DEW POINT DEPRESSIONS AND THUS LESS FOG. FOR NOW...KEPT AREAS OF FOG GOING FROM THE BROOKINGS AREA SOUTHEASTWARD THROUGH OUR EASTERN ZONES. THIS MATCHES UP WITH THE SMALL DEW POINT DEPRESSIONS ADVERTISED BY THE ECMWF IN THOSE AREAS...WITH PATCHY FOG FOR ADJACENT AREAS TO THE WEST...NOT BUYING THE NAM OR RAP OUTPUT. LATE TONIGHT A WELL DEFINED WARM FRONT BEGINS TO NUDGE EASTWARD HELPING TO ACTUALLY WARM TEMPERATURES ACROSS THIS AREA. THIS MAY ALSO HELP IN REDUCING FOG POTENTIAL...AT LEAST WEST OF I 29. FOR TEMPERATURES...LOADED UP THE CHILLY GEM BIAS CORRECTED VALUES FROM SOUTHWEST MN THROUGH THE IA GREAT LAKES REGION...WITH A LOT OF ECMWF ELSEWHERE. SATURDAY SHOULD BE A WARM DAY AHEAD OF THE NEXT CANADIAN FRONT... WHICH WILL MAKE ITS PRESENCE FELT IN OUR NORTHERN ZONES BY AFTERNOON. THEREFORE LOOKING AT SLOWLY FALLING TEMPERATURES NORTH OF I 90 DURING THE AFTERNOON...BUT WITH READINGS STILL FAIRLY MILD. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 231 PM CST FRI NOV 28 2014 IN THE MEDIUM TO LONG RANGE...PATTERN BEGINS TO SHIFT EARLY IN THE WORK WEEK AS WE TRANSITION TO A MOSTLY WESTERLY ZONAL FLOW WHICH WILL EVENTUALLY MODERATE TEMPERATURES TO NEAR NORMAL READINGS. ON SATURDAY NIGHT ANOTHER SHOT OF COLD AIR WILL MOVE INTO THE AREA BEHIND A COLD FRONT WITH LOWS FROM THE SINGLE DIGITS NORTH OF I-90 TO THE TEENS ELSEWHERE. THERE IS THE POTENTIAL FOR FLURRIES ALONG AND JUST BEHIND THE FRONT SO HAVE KEPT IN CHANCE FOR THAT TIME. SURFACE HIGH PRESSURE BUILDS IN AND WILL CONTINUE TO DRAG COLD AIR IN WITH THE COLDEST AIR OVER US ON SUNDAY NIGHT. EXPECT LOWS ON SUN NIGHT TO BE IN THE SINGLE DIGITS WITH SOME AREAS...ESPECIALLY NORTH...SEEING TEMPS AROUND -3 TO -4. VERY COLD TEMPS COMBINED WITH 5-10 MPH WIND WILL RESULT IN WIND CHILL VALUES OF -10 TO -20 RIGHT AROUND THE MORNING COMMUTE. NOT MUCH OF A REBOUND IN TEMPS EXPECTED ON MONDAY WITH HIGHS IN THE TEENS TO LOW 20S. FOR TUESDAY TO FRIDAY...NO SENSIBLE WEATHER TO SPEAK OF AS ZONAL FLOW DOMINATES. TEMPS WILL CONTINUE TO INCH TOWARD MORE SEASONABLE READINGS BY THURS/FRI. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1028 PM CST FRI NOV 28 2014 FOG AND STRATUS IS STRUGGLING TO TAKE HOLD OF THE AREA THIS EVENING. VISIBILITIES HAVE DROPPED TO AROUND 6 TO 8 SM AT SEVERAL LOCATIONS...HOWEVER AREAS OF MVFR OR IFR FOG OR STRATUS SEEMS LESS LIKELY...AS SEEN ON THE MOST RECENT HIGH RES FORECAST MODELS. THE BEST POTENTIAL FOR ANY FOG REACHING MVFR CRITERIA IS ACROSS OUR NORTHEASTERN HALF...MAINLY IN SOUTHWEST MN AND ADJACENT COUNTIES. WILL LEAVE A TEMPO MENTION IN THE KFSD TAF DOWN TO 3SM FROM 08Z- 11Z IN CASE SOME BRIEF REDUCTION IN VISIBILITY DEVELOPS...BUT WITH INCREASING CLOUDS THIS SEEMS LESS LIKELY. LIGHT SOUTHEAST WINDS WILL GRADUALLY TURN NORTHERLY THROUGH THE DAY SATURDAY...INCREASING TO AROUND 10 KT AFTER 00Z/SUN. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ UPDATE... SHORT TERM...MJ LONG TERM...SALLY AVIATION...
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
310 AM EST SAT NOV 29 2014 .SHORT TERM (TODAY AND TONIGHT)... HIGH PRESSURE WILL BE ALONG THE ATLANTIC COASTLINE WHILE A LOW PRESSURE SYSTEM MOVES NE ACROSS THE UPPER MS VALLEY AND GREAT LAKES. THIS WILL PROVIDE A S-SW LOW LEVEL FLOW THROUGH THE SHORT TERM. THE NAM AND GFS SHOW ISENTROPIC LIFT AND MOISTURE ADVECTION SPREADING INTO THE AREA THIS AFTERNOON AROUND 850 MB...AND REMAINING IN PLACE OVERNIGHT. MEANWHILE THE RAP SHOWS VERY LITTLE MOISTURE THROUGH TODAY. THIS DRIER SOLUTION IS GENERALLY PREFERED AS SATELLITE SHOWS NO CLOUDS AT THIS LEVEL UPSTREAM. WILL BRING IN SOME CLOUDS IN THE PLATEAU THIS AFTERNOON...BUT CONFIDENCE IS LOW. IT WILL ALSO MAKE FOR A TRICKY TEMPERATURE FORECAST. WILL LEAN TOWARD THE WARMER GFS MOS FOR HIGHS...BUT CONFIDENCE IS LOW. A TIGHTENING PRESSURE GRADIENT THROUGH THE DAY WILL BRING WINDS UP TO 10-15 MPH WITH SOME GUSTS OF 20-25 POSSIBLE AT TIMES THIS AFTERNOON. .LONG TERM (SUNDAY THROUGH FRIDAY)... ONLY SLIGHT TWEAKS AND CHANGES TO THE FORECAST IN THE LONG TERM... SLIGHT RIDGING STAYS IN PLACE OVER THE AREA ON SUNDAY WHICH WILL LIKELY BE THE WARMEST DAY FOR THE NEXT 7 DAYS FOR MOST LOCATIONS. HIGH PRESSURE MOVES OFF TO THE EAST ON MONDAY AS A COLD FRONT ENTERS THE MIX LATE IN THE DAY BRINGING DECENT CHANCES OF RAIN POST FRONTAL PASSAGE. THINK THE BEST CHANCES FOR RAIN ALONG WITH THE HIGHEST RAINFALL AMOUNTS WILL BE TIED CLOSELY WITH THE FRONT, BUT CHANCES FOR RAIN WILL LINGER THROUGH MID WEEK AS MOISTURE AND POST FRONTAL ISENTROPIC LIFT COULD COMBINE TO BRING LIGHT RAIN SHOWERS ON AND OFF THROUGH THE FIRST PART OF THE WEEK. TAKE A BIT OF A BREAK MID WEEK BEFORE ANOTHER SYSTEM MOVES THROUGH BRINGING IN ABUNDANT MOISTURE FROM THE GULF AND ANOTHER COUPLE OF DAYS WITH CHANCES OF RAIN. && .PRELIMINARY POINT TEMPS/POPS... CHATTANOOGA AIRPORT, TN 57 42 60 48 / 0 0 0 20 KNOXVILLE MCGHEE TYSON AIRPORT, TN 56 39 62 43 / 0 0 10 20 OAK RIDGE, TN 55 41 60 46 / 0 10 10 20 TRI CITIES AIRPORT, TN 54 34 60 38 / 0 0 10 20 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ DGS/ABM
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
543 PM CST SUN NOV 30 2014 .AVIATION... COLD FRONT HAS SLOWED MOVING INTO THE DEEP WARM WESTERLY FLOW OVER THE TEXAS SOUTH PLAINS...WITH LATEST HRRR SHOWING PASSAGE AT KPVW BY 01Z AND KLBB SHORTLY AFTER 02Z. WE HAVE INCORPORATED THESE SLIGHT DELAYS INTO THE LATEST TAF OUTPUT. TRENDS ALSO SUPPORT LESS CONSIDERATION OF AN MVFR CLOUD LAYER FOR KPVW AND KLBB IN PARTICULAR...BUT ALSO LESS CONFIDENCE FOR KCDS AS WELL. THE LOW LEVEL AIRMASS IS PROVING SO DRY THAT EVEN THE SHARP FRONTAL LIFT MAY BE INSUFFICIENT TO DEVELOP MUCH IN THE WAY OF LOW CLOUDS. THE WRF/NAM HOWEVER REMAINS INSISTENT ON THIS LAYER FOR KCDS LATER TONIGHT THROUGH MONDAY MORNING AND THE LATEST HRRR AT LEAST TRIES TO SATURATE THIS LAYER NEAR OR JUST SOUTH OF KCDS BY 06Z-07Z. WE WILL MAINTAIN A BROKEN 2000 FOOT LAYER ONLY FOR KCDS FOR NOW AND REASSESS AS REALITY DEVELOPS. SURFACE GRADIENT WILL GRADUALLY SLACKEN TOMORROW AFTER 18Z...BUT WE DID NOT ADD ANOTHER CHANGE GROUP TO ACCOUNT FOR THIS YET. RMCQUEEN && .PREV DISCUSSION... /ISSUED 328 PM CST SUN NOV 30 2014/ SHORT TERM... WE ARE IN THE MIDST OF ANOTHER UNSEASONABLY WARM DAY AS 20Z TEMPERATURES ARE MOSTLY IN THE 70S...WITH EVEN A FEW LOWER 80S MIXING IN OFF THE CAPROCK. IN FACT...CHILDRESS HAS AGAIN BROKEN ITS RECORD HIGH FOR THE DATE REACHING 81 DEGREES...TWO DEGREES ABOVE THE PREVIOUS RECORD SET IN 1970. LUBBOCK HAS MADE IT TO 79 DEGREES SO FAR WHICH IS A COUPLE OF DEGREES SHY OF THE RECORD SET IN 2012. AS ADVERTISED FOR SOME TIME...THIS NEAR RECORD TO RECORD WARMTH WILL COME TO AN ABRUPT END THIS EVENING AS A STRONG COLD FRONT PLUNGES THROUGH. AS OF 20Z...THE COLD FRONT WAS ALREADY EDGING INTO THE NORTHEASTERN ZONES...STRETCHING FROM DALHART TO GOODNIGHT TO MEMPHIS TO NEAR ALTUS OKLAHOMA. THIS FRONT WAS ADVANCING STEADILY SOUTHWEST AND IT WILL ACCELERATE THROUGH THE LATE AFTERNOON AND EVENING HOURS...LIKELY PUSHING THROUGH LUBBOCK BETWEEN 01-03Z AND CLEARING THE FAR SOUTHWEST ZONES BY AROUND OR SHORTLY AFTER MIDNIGHT. GIVEN AFTERNOON TEMPERATURES BEHIND THE FRONT IN KANSAS ARE ONLY IN THE 20S...THERE WILL BE STOUT COLD AIR ADVECTION BEHIND THE FRONT. EXPECT GUSTY NORTHEASTERLY WINDS SUSTAINED AT 15 TO 25 MPH TO BE COMMON MUCH OF THE OVERNIGHT WITH MORNING LOWS BOTTOMING OUT IN THE TEENS NORTH TO LOWER TO MIDDLE 20S SOUTH. THESE TEMPERATURES... COUPLED WITH THE WINDS...WILL RESULT IN WIND CHILLS IN THE SINGLE DIGITS FOR MANY SPOTS TOMORROW MORNING MAKING FOR BRUTAL BUT APPROPRIATE START TO DECEMBER. THERE REMAINS SOME UNCERTAINTY WHETHER OR NOT A SHALLOW LAYER OF STRATUS WILL FORM WELL BEHIND THE FROPA LATE TONIGHT GIVEN STRONG COOLING ACTING ON A RELATIVELY DRY AIRMASS. WE WOULD EXPECT AT LEAST SOME STRATUS TO ROAM THE AREA MONDAY MORNING...LIKELY FAVORING SPOTS OFF THE CAPROCK WHERE THERE WILL BE A LITTLE MORE MOISTURE TO WORK WITH...THOUGH ALMOST ANYWHERE COULD SEE A SHORT BOUT OF STRATUS. WHATEVER LOW CLOUDS FORM SHOULD GRADUALLY DIMINISH BY MIDDAY OR EARLY AFTERNOON MONDAY...THOUGH A WEAK SHORTWAVE GLIDING BY TO THE NORTH IN NEAR ZONAL FLOW ALOFT WILL INCREASE HIGH CLOUDS DURING THE AFTERNOON HOURS. NO RECORD HIGHS WILL BE BROKEN TOMORROW WITH TEMPERATURES ONLY EXPECTED TO PEAK IN THE 30S FOR MOST SPOTS. THE BREEZY NORTH WINDS IN THE MORNING WILL GRADUALLY DIMINISH THROUGH THE AFTERNOON AS THE PRESSURE GRADIENT RELAXES. LONG TERM... ONLY MINOR CHANGES MADE TO THIS LONG TERM FORECAST...AS THE FOCUS NOW SHIFTS TO INCREASING PRECIPITATION CHANCES TOWARDS THE WEEKEND. WHILE SOME MODEL SOLUTIONS CONTINUE TO INDICATE THAT LIGHT RAIN COULD BEGIN AS EARLY AS LATE THURSDAY...ALL INDICATIONS ARE THAT BEST CHANCES WILL OCCUR LATE SATURDAY THROUGH SUNDAY. TO BEGIN THE PERIOD EARLY TUESDAY...TEMPERATURES SHOULD QUICKLY RECOVER INTO THE 50S AND LOW 60S FOLLOWING MONDAYS COLD FRONT...AS PRESSURE FALLS ACROSS THE HIGH PLAINS WILL FORCE THE QUICK RETURN OF SOUTHWEST WINDS. THIS WILL ALSO DRAW INCREASING MOISTURE NORTHWARD THROUGH THE DAY AND OVERNIGHT...AND MODEL GUIDANCE SUGGESTS THAT THIS MAY BE ENOUGH TO RESULT IN SOME PATCHY FOG ACROSS THE SOUTHERN SOUTH AND ROLLING PLAINS BY EARLY WEDNESDAY MORNING. FARTHER NORTH...MORE LIMITED MOISTURE AND THE PRESENCE OF A SUBSTANTIAL MID TO HIGH LEVEL CLOUD LAYER WILL LIKELY PROVE TO PROHIBITIVE FOR FOG DEVELOPMENT...AND MAY EVEN LIMIT IT TO AREAS ACROSS THE PERMIAN BASIN. STILL...ENOUGH CONFIDENCE EXISTS FOR SOME LOW-END MENTION AT THIS TIME ACROSS THE AREAS PREVIOUSLY MENTIONED. DURING THE DAY WEDNESDAY...YET ANOTHER SUBTLE AND PROGRESSIVE SHORTWAVE WILL MOTOR ACROSS THE AREA...SENDING YET ANOTHER COLD FRONT THROUGH THE REGION. ACROSS THE BOARD...LATEST GUIDANCE HAS TRENDED A BIT STRONGER WITH THIS FRONT THAN IN PREVIOUS SOLUTIONS...SO WE OPTED TO COOL WEDNESDAYS HIGHS A FEW MORE DEGREES...PARTICULARLY ACROSS THE NORTHERN SOUTH AND ROLLING PLAINS. IN ANY CASE...THIS WAVE APPEARS TO BE ANOTHER DRY ONE. ALL EYES THEN TURN TO THE NEXT WAVE...WHICH CONTINUES TO BE HANDLED WITH POOR AGREEMENT AMONGST MODELS DESPITE GENERAL OVERALL IMPROVEMENT THROUGH THE REST OF THE LONG TERM PERIOD. ON ONE HAND...THE GFS CONTINUES TO INDICATE A MORE POTENT SHORTWAVE WITH MORE RAPID MOISTURE RETURN...AND LIKEWISE DEVELOPS LIGHT QPF ACROSS PRIMARILY THE SOUTHERN SOUTH PLAINS AND ROLLING PLAINS AS EARLY AS LATE THURSDAY. OVERALL...IT DOES APPEAR THAT DESPITE ITS STUBBORNNESS WITH THIS PARTICULAR FEATURE...THE GFS SEEMS TO BE DRIFTING CLOSER TO THE ECMWF IN ITS DEPICTION OF THE REMAINDER OF THE LONG TERM PERIOD. THUS...WE WILL CONTINUE TO MAINTAIN A DRY FORECAST THROUGH AT LEAST EARLY SATURDAY WHEN A MUCH MORE SUBSTANTIAL WAVE IS EXPECTED TO IMPACT THE AREA. WHILE SLIGHT TIMING DIFFERENCES PERSIST...THE WINDOW FOR SUBSTANTIAL PRECIPITATION SEEMS TO BE NARROWING TO A LATE SATURDAY THROUGH SUNDAY TIME FRAME. AT 6-7 DAYS AWAY...MANY DETAILS REMAIN UNCLEAR...BUT SLOWLY IMPROVING AGREEMENT AMONG SOLUTIONS IS PROMISING. FIRE WEATHER... NEAR RECORD TEMPERATURES...HUMIDITIES OF 7 TO 13 PERCENT AND WESTERLY WINDS SUSTAINED AT 15 TO 25 MPH WERE CREATED ELEVATED TO BRIEFLY CRITICAL FIRE WEATHER ACROSS MOST OF THE CAPROCK THIS AFTERNOON. CONDITIONS WILL QUICKLY IMPROVE BY EARLY EVENING AS WINDS DIMINISH...BUT A COLD FRONT WILL PLUNGE FROM NORTHEAST TO SOUTHWEST ACROSS THE SOUTH PLAINS THROUGH THE EVENING HOURS BRINGING AN ABRUPT NORTHEASTERLY WIND SHIFT THAT COULD COMPLICATE ANY ONGOING FIRE FIGHTING OPERATIONS. GUSTY NORTHEASTERLY WINDS...DRASTICALLY COLDER TEMPERATURES AND IMPROVING HUMIDITIES WILL FOLLOW THE COLD FRONT WITH HIGHS ON MONDAY AFTERNOON ABOUT 40-50 DEGREES COLDER THAN TODAY. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 16 35 17 64 38 / 0 0 0 0 0 TULIA 16 34 19 60 39 / 0 0 0 0 0 PLAINVIEW 17 36 21 59 40 / 0 0 0 0 0 LEVELLAND 20 39 22 61 39 / 0 0 0 0 0 LUBBOCK 19 38 23 60 40 / 0 0 0 0 0 DENVER CITY 24 40 26 58 40 / 0 0 0 0 0 BROWNFIELD 23 39 25 59 40 / 0 0 0 0 0 CHILDRESS 22 36 22 58 41 / 0 0 0 0 0 SPUR 21 37 23 59 40 / 0 0 0 0 0 ASPERMONT 24 37 26 59 43 / 0 0 0 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99/05
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AREA FORECAST DISCUSSION
NWS GREEN BAY WI
545 PM CST SUN NOV 30 2014 UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE .SHORT TERM...TONIGHT AND MONDAY ISSUED AT 252 PM CST SUN NOV 30 2014 THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A POLAR FRONT MOVING ACROSS MICHIGAN EARLY THIS AFTERNOON. EARLIER TEMPERATURES IN THE MIDDLE 30S OVER EASTERN WISCONSIN HAVE FALLEN INTO THE UPPER 20S OVER MUCH OF THE FOX VALLEY. LIGHT LAKE EFFECT SNOW SHOWERS CONTINUE TO PASS OVER N-C WISCONSIN WHERE TEMPS HAVE HOVERED ALL DAY IN THE TEENS. LOOKING UPSTREAM...MOSTLY CLEAR CONDITIONS RESIDE UPSTREAM OVER THE NORTHERN PLAINS THANKS TO A STRONG HIGH PRESSURE SYSTEM BUILDING INTO THAT PART OF THE COUNTRY. A REINFORCING ARCTIC FRONT IS DROPPING SOUTHEAST OVER THE LAKE WINNIPEG REGION...AND IS POISED TO MOVE THROUGH THE REGION TONIGHT. WITH THE PASSAGE OF THIS ARCTIC FRONT...WIND CHILL HEADLINES ARE THE MAIN FORECAST CONCERN. TONIGHT...A STRONG SHORTWAVE WILL MOVE ACROSS ONTARIO AND WILL DRIVE AN ARCTIC FRONT ACROSS THE STATE AFTER MIDNIGHT. AHEAD OF THE FRONT...MODELS PROJECT MID-LEVEL MOISTURE PULLING OUT TO THE NORTHEAST AND LOW LEVEL MOISTURE EXITING WITH THE POLAR FRONT. LAKE CLOUDS SHOULD ALSO BE RETREATING TO THE UPPER PENINSULA AS WINDS BACK MORE WESTERLY. THIS SHOULD LEAD TO MOSTLY CLEAR CONDITIONS FOR MUCH OF THE NIGHT. MODELS INDICATE THAT STRATO-CU COULD MOVE INTO NORTHERN WISCONSIN BEHIND THE ARCTIC FRONT AFTER MIDNIGHT...BUT THIS LOOKS OVERDONE BASED ON CLOUDS UPSTREAM. 925MB TEMPS WILL FALL INTO THE -20S BEHIND THE ARCTIC FRONT BY 12Z MONDAY AND UPSTREAM OBS OVER THE EASTERN DAKOTAS SUGGEST LOW TEMPS WILL FALL INTO THE MIDDLE SINGLE DIGITS BELOW ZERO OVER THE NORTH. THIS MATCHES FAIRLY WELL WITH THE AVERAGE BIAS CORRECTED GUIDANCE...AND THE PREVIOUS FORECAST. COMBINED WITH A BRISK NORTHWEST WIND...WIND CHILLS WILL FALL BETWEEN 20 AND 25 BELOW OVER N-C WISCONSIN. AS A RESULT...WILL HOIST A WIND CHILL ADVISORY STARTING LATE TONIGHT. MONDAY...COLD ADVECTION WILL CONTINUE MONDAY MORNING...AND COULD SEE TEMPERATURES CONTINUE TO FALL OVER EASTERN WISCONSIN THROUGH MID-MORNING. ARCTIC HIGH PRESSURE WILL THEN BUILD IN FOR THE AFTERNOON...AND SHOULD SEE THE GUSTY NORTHWEST WINDS SUBSIDE. THOUGH TEMPS ALOFT WILL BE MODIFYING...HIGHS WILL ONLY RANGE FROM THE SINGLE DIGITS ABOVE ZERO TO THE LOWER TEENS UNDER PLENTY OF SUNSHINE. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 252 PM CST SUN NOV 30 2014 UNLIKE NOVEMBER...DECEMBER LOOKS LIKE IT WILL BE RATHER MILD AT LEAST FOR THE FIRST WEEK OR SO. THE UPPER FLOW IS MOSTLY ZONAL WITH SURFACE HIGHS COMING FROM THE ROCKIES INSTEAD OF THE ARCTIC. TEMPERATURES ALOFT ARE GENERALLY TOO WARM FOR SIGNIFICANT LAKE EFFECT AND THERE ARE NO SIGNIFICANT SURFACE LOWS FORECAST TO IMPACT THE NORTHERN GREAT LAKES. THERE COULD BE SOME LAKE EFFECT SNOW FLURRIES OVER DOOR COUNTY LATE MONDAY NIGHT OR EARLY TUESDAY WAS SOUTHERLY FLOW MIGHT BE JUST COLD ENOUGH TO GET SOME SNOW SHOWERS. A WEAK COLD FRONT MOVING THROUGH TUESDAY EVENING MIGHT PRODUCE SOME SNOW SHOWERS BUT IT DOESN/T LOOK TO BE VERY MUCH. IT WILL START OUT ABOUT 5 DEGREES BELOW NORMAL TUESDAY AND WEDNESDAY BUT THEN TEMPERATURES WILL BE 5 TO 8 DEGREES ABOVE NORMAL AFTER THAT. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 535 PM CST SUN NOV 30 2014 ASIDE FROM A FEW LAKE-EFFECT SNOW SHOWERS OR FLURRIES OVER NORTHERN VILAS COUNTY...DRY CONDITIONS ARE ANTICIPATED THROUGH THE TAF PERIOD. SOME MID/HIGH LEVEL CLOUDS WILL EXIT THE REGION THIS EVG...AND SCT STRATOCUMULUS MAY ACCOMPANY A SURGE OF COLDER AIR LATE TONIGHT INTO EARLY MONDAY...BUT VFR CONDITIONS WILL PREVAIL. THE MAIN AVIATION CONCERN WILL BE A BRIEF SHOT OF STRONG NW WINDS LATE TONIGHT INTO MONDAY MORNING...WITH GUSTS TO NEAR 25 KTS EXPECTED AT MOST LOCATIONS. THE WINDS WILL QUICKLY DECREASE AS ARCTIC HIGH PRESSURE ARRIVES MONDAY AFTERNOON. && .GRB WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY FROM 3 AM TO 10 AM CST MONDAY FOR WIZ005- 010>012-018-019-030. && $$ SHORT TERM.....MPC LONG TERM......RDM AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1109 PM CST FRI NOV 28 2014 .UPDATE... ISSUED AT 858 PM CST FRI NOV 28 2014 LOCAL RADAR AND REPORTS FROM LAW ENFORCEMENT ACROSS CENTRAL WISCONSIN INDICATE MOST...IF NOT ALL...OF THE LIGHT FREEZING RAIN HAS MOVED OUT OF THE AREA. THERE COULD STILL BE A LITTLE BIT OF FREEZING RAIN OR SLEET ACROSS SOUTHERN CLARK COUNTY THROUGH 10 PM...BUT THIS IS NOT WIDESPREAD ENOUGH OR HEAVY ENOUGH TO CAUSE ANY PROBLEMS. CHECKING WITH LAW ENFORCEMENT IN CLARK COUNTY...THEY HAVE NOT HAD ANY PROBLEMS YET TONIGHT DESPITE SOME DECENT RADAR RETURNS THAT MOVED ACROSS. OTHER REPORTS INDICATE THE FREEZING RAIN HAS ENDED AND THAT PRIMARY HIGHWAYS ARE IN GOOD SHAPE BUT SOME OF THE SECONDARY ROADS THAT HAVE NOT BEEN TREATED REMAIN SLICK. WILL LET THE FREEZING RAIN ADVISORY EXPIRE AS SCHEDULED AT 9 PM. UPDATE ISSUED AT 450 PM CST FRI NOV 28 2014 SCATTERED FREEZING RAIN SHOWERS CONTINUE ALONG AND NORTH OF INTERSTATE 90 WITH SOME LOCAL LAW ENFORCEMENT AGENCIES STARTING TO REPORT SOME SLICK ROADS AND ACCIDENTS. LOOKING AT THE LATEST HRRR...THIS SHOULD CONTINUE INTO THE EARLY EVENING BEFORE PUSHING OFF TO THE EAST AND OPTED TO ISSUE A FREEZING RAIN ADVISORY WITH SOME ICING STARTING TO OCCUR AND TO RAISE THE AWARENESS. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 350 PM CST FRI NOV 28 2014 AT 3 PM...A BAND OF MODERATE TO STRONG 700 TO 500 MB FRONTOGENESIS WAS STARTING TO MOVE EAST INTO WEST CENTRAL WISCONSIN. THIS BAND HAS PRODUCED AREAS OF FREEZING RAIN AND OCCASIONALLY SOME ICE PELLETS ACROSS SOUTHEAST MINNESOTA. PERIODIC CHECKS WITH LAW ENFORCEMENT AND SPOTTERS HAVE NOT INDICATED TOO MUCH OF AN IMPACT FROM IT. IT JUST STARTED HERE AT THE OFFICE AND IT IS FREEZING ON THE VEHICLES AND SLICK SPOTS ON UNTREATED SIDEWALKS. HAVE TO ISSUE A SPECIAL WEATHER STATEMENT FOR AREAS ALONG AND NORTH OF INTERSTATE 90 TO COVER THE POTENTIAL FOR LIGHT ICING ON UNTREATED SURFACES. FOR THIS EVENING...THE 28.18Z RAP AND NAM SHOW THAT THIS BAND WILL CONTINUE TO MOVE EAST ACROSS WEST CENTRAL...CENTRAL...AND NORTH CENTRAL WISCONSIN. AS IT MOVES INTO NORTH CENTRAL WISCONSIN... SOUNDINGS SUGGEST THAT THERE MAY BE A BRIEF PERIOD OF SNOW MIXING IN WITH THIS WINTRY MIX. SOME OF THE MESO MODELS SUGGEST UP TO A TENTH OF AN INCH OF QPF. THIS SEEMS TO BE A BIT ON THE HIGH SIDE CONSIDERING THE DRY AIR BETWEEN 700 TO 850 MB...SO HAVE LIQUID AMOUNTS OF 0.01 TO 0.03 INCHES. FOR OVERNIGHT...EXPECT THE WINTRY PRECIPITATION TO BE IN CLARK AND TAYLOR COUNTIES...AND THEN MOVE OUT BY 3 AM. THERE MAY BE SOME VERY LIGHT ICING. STRONG WARM AIR ADVECTION WILL CAUSE RISING TEMPERATURES THROUGH THE NIGHT. TEMPERATURES WILL RISE FROM THE LOWER TO MID 20S INTO THE MID AND UPPER 20S BY MORNING. AS THIS WARM AIR MOVES OVER THE SNOW PACK...THERE MAY BE SOME AREAS OF FOG. ON SATURDAY...THE TEMPERATURE FORECAST IS PROBLEMATIC DUE TO THE SNOW COVER. THE NAM SNOW COVER IS INITIALIZED TOO HIGH. IT HAS SNOW DEPTHS OF 4 TO 8 INCHES. WE ARE ACTUALLY MORE IN THE TRACE TO 4 INCHES...SO SOME OF THE WARMING IN THE MODELS IS GOING TO SNOW MELT INSTEAD OF WARMING THE AIR MASS NEAR THE GROUND. THE WARMEST 925 AND 850 MB TEMPERATURES ARE LOCATED ALONG AND SOUTH OF INTERSTATE 90. 925 MB TEMPERATURES WILL CLIMB TO 0 TO 8C INTO THESE AREAS...SO A BIT CONCERNED THAT THE TEMPERATURES COULD WARM A BIT WARMER THAN THE LOW TO MID 40S THAT ARE CURRENTLY FORECAST. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 350 PM CST FRI NOV 28 2014 ON SATURDAY NIGHT AND SUNDAY MORNING...THE FIRST OF 2 ARCTIC COLD FRONT WILL MOVE SOUTHEAST THROUGH THE AREA. 850 MB TEMPERATURES FALL FROM 6 TO 10C INTO -7 TO -15C. THE STRONG COLD AIR ADVECTION WILL CAUSE TEMPERATURES TO SLOWLY FALL THROUGH MUCH OF THE DAY. WAS INITIALLY CONCERNED ABOUT STRONG WINDS ADVECTING TO THE SURFACE DUE TO STRONG SUBSIDENCE IN THE WAKE OF THIS FRONT. HOWEVER SOUNDINGS CONTINUE TO SHOW THAT THE WINDS WILL STAY MAINLY IN THE 15 TO 25 MPH. THIS WILL PRODUCE WIND CHILLS IN THE 10 BELOW TO 10 ABOVE RANGE. ON SUNDAY NIGHT...ANOTHER COLD FRONT WILL MOVE THROUGH THE AREA. THIS WILL LOWER 850 MB TEMPERATURES DOWN INTO THE -15C TO -19C FOR MONDAY MORNING BEFORE WARM AIR ADVECTION STARTS TO DEVELOP ACROSS THE AREA DURING THE AFTERNOON AND MONDAY NIGHT. HIGH TEMPERATURES ON MONDAY WILL RANGE FROM 5 TO 15 DEGREES. LIGHTER WINDS WILL KEEP WIND CHILLS IN THE 10 BELOW TO 10 ABOVE RANGE. FROM THURSDAY INTO THURSDAY NIGHT...THE MODELS CONTINUE TO STRUGGLE WITH WHETHER A LOW PRESSURE SYSTEM WILL BRING PRECIPITATION TO THE AREA. THE GFS AND ECMWF ARE NOW SIMILAR WITH THE TRACK THROUGH THE MID MISSISSIPPI RIVER VALLEY AND WESTERN GREAT LAKES. HOWEVER THEY ARE 12 HOUR APART. PRECIPITATION TYPE WILL BE SNOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1109 PM CST FRI NOV 28 2014 WILL ALL OF THE PRECIPITATION NOW WELL NORTHEAST OF BOTH TAF SITES...SATELLITE IMAGERY INDICATES SKIES HAVE BEGUN TO CLEAR OUT. THIS HAS ALLOWED SOME FOG TO BEGIN FORMING WITH A FEW SITES AROUND THE REGION REPORTING SOME MVFR VISIBILITIES. THE 29.03Z RAP CONTINUES TO HAVE A GOOD HANDLE ON THE LOW LEVEL MOISTURE FIELDS AND THE LACK OF LOW CLOUDS. IT STILL SHOWS THAT THE LOW LEVELS WILL NOT SATURATE OVERNIGHT BUT THAT THERE WILL LIKELY BE SOME FOG FOR BOTH TAF SITES AND HAVE CONTINUED TO SHOW MVFR VISIBILITIES THROUGH THE MIDDLE OF SATURDAY MORNING. AFTER THAT...VFR CONDITIONS ARE EXPECTED FOR THE REST OF THE PERIOD AHEAD OF A COLD FRONT THAT WILL BE APPROACHING FROM THE WEST. WITH A LACK OF MOISTURE TO WORK WITH...SHOULD ONLY SEE SOME HIGH CLOUDS AHEAD OF THE FRONT AND NOT EXPECTING THE WIND SHIFT TO OCCUR UNTIL AFTER 30.06Z. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...04 SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...04
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
1158 PM CST SUN NOV 30 2014 .AVIATION...01/06Z TAF CYCLE THE COLD FRONT IS NOW ACROSS NORTHERN ARKANSAS FORT SMITH TO EVENING SHADE. WINDS WILL TURN TO THE NORTH BEHIND THE FRONT. ALSO MUCH COLDER AIR WILL BE USHERED IN WITH THE FRONT. DRIZZLE AND SLEET WILL TURN TO FREEZING DRIZZLE IN THE NORTH THIS COMING MORNING. LIGHT RAIN IS EXPECTED CENTRAL AND SOUTH. ALSO...CEILINGS WILL BE LOWERING THROUGH THE NIGHT. VFR CONDITIONS WILL BECOME MAINLY MVFR AND PERSIST FOR MOST OF THE PERIOD. && .PREV DISCUSSION... /ISSUED 937 PM CST SUN NOV 30 2014/ UPDATE... NO APPRECIABLE CHANGES WILL BE FORTH COMING THIS EVENING. LATEST SURFACE ANALYSIS SHOWS THE COLD FRONT HAS CLEARED NORTHWEST ARKANSAS WITH TEMPERATURES ALREADY DOWN IN THE UPPER 30S IN BENTON COUNTY. LZK 00Z SOUNDING SHOWS CONSIDERABLE LAYER OF DRY AIR JUST OFF THE DECK BUT KSGF RAOB IS MOISTENING UP. WOULD NOT BE SURPRISED TO SEE AS LITTLE SLEET MIXED IN BASED ON THIS SOUNDING. PRECIP CHANCES MAY BE DELAYED A SHORT TIME BUT HRRR AND NEW NAM DOES SHOW PRECIPITATION STARTING OVER THE NEXT FEW HOURS. TIMING AND PLACEMENT OF THE WINTER WEATHER ADVISORY STILL LOOK GOOD AND AMOUNTS OF ACTUAL ICE STILL LOOK TO BE UNDER A TENTH OF AN INCH. PRIMARY CONCERN WILL REMAIN ELEVATED SURFACES. PREV DISCUSSION... /ISSUED 248 PM CST SUN NOV 30 2014/ SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT THE MAIN CONCERN FOR THE SHORT TERM IS THE IMPENDING WINTER WEATHER SLATED TO AFFECT THE NORTHERN PARTS OF ARKANSAS TONIGHT. AS SUCH THE DISCUSSION WILL FOCUS PRIMARILY ON THAT. REGIONAL SURFACE ANALYSIS SHOWS A STARK COLD FRONT SITUATED FROM SOUTH OF OKLAHOMA CITY...THROUGH SOUTH OF TULSA...AND THROUGH ROUGHLY THE SPRINGFIELD MISSOURI AREA THIS AFTERNOON. THIS FRONT WILL CREEP SOUTHWARD THROUGH ARKANSAS OVER THE NEXT 24 HOURS OR SO...FINALLY PUSHING SOUTH OF THE STATE BY MONDAY EVENING. FROPA SHOULD BE OCCUR JUST BEFORE MIDNIGHT TONIGHT AT HARRISON...AROUND DAYBREAK AT PLACES LIKE LITTLE ROCK...MOUNT IDA...AND CLARENDON...AND FINALLY BY EARLY AFTERNOON IN THE FAR SOUTH. AHEAD OF THE FRONT UNSEASONABLY WARM AND HUMID CONDITIONS HAVE BEEN SEEN THIS WEEKEND...WITH HIGHS TODAY RISING INTO THE UPPER 70S IN PLACES. CONVERSELY...HIGHS FOR MANY PLACES TOMORROW WILL BE DURING THE EARLY MORNING HOURS...WITH TEMPERATURES FALLING INTO THE MID 30S BEHIND THE FRONT DURING THE DAY MONDAY. MEANWHILE...A WEAK DISTURBANCE WILL BEGIN TO APPROACH FROM THE WEST LATER TODAY AND EVENTUALLY MOVE EAST OF THE STATE BY MON EVENING...RESULTING IN LIGHT PRECIP ACROSS THE FORECAST AREA FROM LATE TONIGHT THROUGH THE DAY MONDAY. INITIALLY THIS WILL BEGIN AS RAIN...BUT AS THE AFOREMENTIONED COLD FRONT BEGINS TO PUSH INTO ARKANSAS FROM THE NORTH...THE POST FRONTAL AIR SHOULD BE SUFFICIENTLY COLD AND DEEP ENOUGH TO CHANGE PRECIPITATION TO MAINLY FREEZING RAIN. ONE CAVEAT WOULD BE THAT THERE ARE SOME CONVECTIVE ELEMENTS NOTED IN MODEL OUTPUT SO I WOULD NOT BE SURPRISED TO SEE SOME SLEET DEVELOP IN PLACES...MAINLY IN NORTH CENTRAL AND NORTHEAST ARKANSAS TOMORROW MORNING. HOWEVER MUCH OF THE MOISTURE WILL REMAIN BELOW THE DENDRITIC GROWTH ZONE SO THE PREDOMINANT PRECIPITATION TYPE SHOULD BE FREEZING RAIN. PRECIPITATION AMOUNTS SHOULD NOT BE TOO HIGH. THE...RELATIVELY SPEAKING...HEAVIEST PERIOD OF PRECIPITATION WILL BE AS THE UPPER DISTURBANCE MOVES THROUGH MID MORNING INTO THE AFTERNOON HOURS TOMORROW...AND EVEN THEN MODELS ARE SHOWING LESS THAN A QUARTER OF AN INCH OF QPF IN THE HEAVIEST SPOTS. ONCE THE DISTURBANCE PASSES THERE SHOULD STILL BE ENOUGH MOISTURE LEFTOVER FOR SOME LINGERING FREEZING DRIZZLE THROUGH LATE MON EVENING. PRECIPITATION SHOULD BEGIN WINDING DOWN...AND TEMPERATURES STILL WARM ENOUGH...TO CONFINE ANY WINTRY PRECIPITATION TO MAINLY THE NORTHERN TWO ROWS OF COUNTIES. GIVEN THE CURRENT UNSEASONABLY WARM AIR TEMPERATURES AND THE RESULT THIS HAS HAD ON GROUND TEMPS...DO NOT EXPECT THERE TO BE AN IMMEDIATE ACCRUAL OF ICE ON ANY SURFACE ONCE THE FRONT PASSES AND TEMPERATURES FALL BELOW THE FREEZING MARK IN ANY GIVEN LOCATION. HOWEVER WITH TEMPS REMAINING BELOW FREEZING...AREAS IN NRN ARKANSAS WILL UNDOUBTEDLY BEGIN TO SEE ACCUMULATING ICE BEFORE MIDDAY MON. THIS IS MOST LIKELY TO OCCUR ON ELEVATED SURFACES LIKE TREES AND POWERLINES...BUT BY MON EVENING ROADWAYS WILL LIKELY BE COLD ENOUGH SUCH THAT ANY FURTHER FREEZING DRIZZLE OR LIGHT FREEZING RAIN COULD CAUSE SOME SLICK SPOTS AND HAZARDOUS TRAVEL. FOR THESE REASONS...HAVE HOISTED UP A WINTER WEATHER ADVISORY IN THE NRN TWO ROWS OF COUNTIES TO ACCOUNT FOR THIS. FEEL THAT...DESPITE LACK OF SIGNIFICANT ICE ACCUMULATION...THERE WILL STILL BE ENOUGH TRAVEL IMPACTS TO WARRANT AN ADVISORY. ELSEWHERE...CENTRAL AND SOUTHERN ARKANSAS SHOULD NOT SEE COLD ENOUGH TEMPERATURES WHILE PRECIP IS ONGOING TO WARRANT ANY CONCERNS AT THIS TIME. OTHERWISE...COOLER THAN NORMAL TEMPERATURES WILL AFFECT THE STATE THROUGH TUESDAY. BUT A WARMUP IS EXPECTED AS WE HEAD INTO WED. THE FRONT MOVING THROUGH TOMORROW WILL LIFT BACK NORTH INTO ARKANSAS ON WED...AND A SIMILAR SITUATION IN TERMS OF WIDESPREAD LIGHT PRECIPITATION SHOULD DEVELOP WED NIGHT. THIS TIME ONLY RAIN IS EXPECTED THOUGH AS THERE WILL BE NO ARCTIC BOUNDARY PUSHING INTO THE REGION FROM THE NORTH TO CHANGE PRECIPITATION OVER. LONG TERM...THURSDAY THROUGH SUNDAY AN UNSETTLED WEATHER PATTERN WILL BE OVER THE CENTRAL U.S. AND KEEP RAIN CHANCES IN THE FORECAST EVERY DAY. THE NEARLY ZONAL UPPER PATTER WILL KEEP TEMPS WELL ABOVE FREEZING IN NORMAL VALUES...AND ALLOW SHORT WAVE ENERGY TO MOVE THROUGH THE PATTERN AND AFFECT AR. THURSDAY WILL START WITH A WEAK FRONTAL BOUNDARY NEARLY STATIONARY OVER AR...WITH MAINLY A SHOWER POTENTIAL FOR THURSDAY AND FRIDAY. A BIT MORE SHORT WAVE ENERGY IS SEEN IN THE MODELS FRIDAY AND OVER THE WEEKEND...SO A BIT BETTER RAIN CHANCES WITH SLIGHT CHANCES OF THUNDER ARE IN THE FORECAST OVER THE WEEKEND. && .LZK WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM CST MONDAY FOR BAXTER- BOONE-FULTON-IZARD-MARION-NEWTON-SEARCY-SHARP-STONE. && $$ AVIATION...51
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
100 AM EST MON DEC 1 2014 .SYNOPSIS... HIGH PRESSURE WILL PREVAIL TODAY. A COLD FRONT WILL ADVANCE FROM THE NORTH TUESDAY...FOLLOWED BY A WEAK WEDGE OF HIGH PRESSURE. A STRONGER WEDGE OF HIGH PRESSURE WILL DEVELOP LATE WEEK INTO NEXT WEEKEND. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... IT APPEARS A WIDESPREAD DENSE FOG EVENT IS IN THE OFFING FOR MUCH OF THE AREA TONIGHT. CALM WINDS AT THE SURFACE AND THE KCLX VAD WIND PROFILE SHOWS LIGHT/VARIABLE WINDS UP TO 4 KFT...SUGGESTING VERY LITTLE WIND EXISTS EVEN ATOP THE NOCTURNAL INVERSION. ABUNDANT LOW-LEVEL MOISTURE IS IN PLACE WITH DEWPOINTS RUNNING ABOUT 8-12 DEGREES HIGHER THAN 24 HOURS AGO. CLEAR SKIES...RICH LOW-LEVEL MOISTURE AND CALM WINDS WILL SUPPORT ANOTHER ROUND OF DENSE FOG-- SIMILAR...IF NOT MORE DENSE/WIDESPREAD... THAN WHAT OCCURRED THIS MORNING. HIGH RESOLUTION DATA SETS INCLUDING THE RAP AND H3R HAVE BEEN CONSISTENT FOR MANY CONSECUTIVE RUNS NOW IN THEIR DEPICTION OF WIDESPREAD DENSE FOG ENCOMPASSING ALL OF SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA AFTER MIDNIGHT... ESPECIALLY FROM 2-3 AM ON. GOES-EAST IFR PROBABILITIES HAVE BEEN STEADILY INCREASING EAST OF I-95 OVER THE PAST FEW HOURS AND A FEW OBSERVATION SITES HAVE BEEN REPORTING VSBYS AS LOW AS 1 MILES ALREADY...SUGGESTING DENSE FOG INITIATION HAS BEGUN. A DENSE FOG ADVISORY MAY BE ISSUED FOR ALL OR PORTIONS OF THE FORECAST AREA OVERNIGHT. FOR THE MIDNIGHT UPDATE WE MADE VERY MINOR ADJUSTMENTS TO HOURLY DEWPOINTS AND TEMPERATURES. && .SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY/... MONDAY...THE PATTERN AT THE SURFACE AND ALOFT WILL BE TRANSITIONING THROUGH THE DAY...AS DEEP LAYER RIDGING RETREATS FARTHER INTO THE ATLANTIC AHEAD OF A COLD FRONT APPROACHING FROM THE NORTHWEST. ONCE FOG DISSIPATES BY MID MORNING...MOSTLY CLEAR TO PARTLY CLOUDY SKIES WILL ALLOW SUFFICIENT INSOLATION WITHIN WARM SOUTHWEST FLOW TO SUPPORT ANOTHER UNSEASONABLY WARM DAY. WILL ADVERTISE HIGH TEMPERATURES PEAKING IN THE LOW TO MID 70S AWAY FROM THE LOCALLY COOLER COASTLINE. WILL NEED TO MONITOR THE POTENTIAL FOR FOG DEVELOPMENT AFTER MIDNIGHT...AS SEVERAL GUIDANCE SOURCES SUGGEST AREAS OF FOG COULD AGAIN IMPACT PORTIONS OF THE FORECAST AREA ONCE LOW LEVEL MOISTURE BECOMES TRAPPED BENEATH THE INVERSION. EXPECT MILDER LOW TEMPERATURES RANGING FROM THE UPPER 40S TO LOW 50S. TUESDAY...THE FRONT WILL LIKELY STALL IN THE VICINITY AND FORM THE LEADING EDGE OF AN INLAND WEDGE OF HIGH PRESSURE BUILDING DOWN THE LEE OF THE APPALACHIANS. THE PARENT SURFACE HIGH WELL TO THE NORTH WILL BE RATHER TRANSIENT IN NATURE...AND THUS THERE IS SOME UNCERTAINTY REGARDING THE STRENGTH OF THE WEDGE AND ITS ASSOCIATED SENSIBLE WEATHER IMPACTS. PREFER TO MAINTAIN PERSISTENCE AT THIS TIME AND INDICATE A RATHER SHARP TEMPERATURE GRADIENT FROM NORTHWEST TO SOUTHEAST...AS IS EXPECTED IN A WEDGE TYPE SCENARIO. WILL ADVERTISE HIGH TEMPERATURES RANGING FROM THE LOW 60S CHARLESTON TRI COUNTY REGION TO THE LOW 70S FARTHER SOUTH NEAR THE ALTAMAHA RIVER IN GEORGIA. ANY MEASURABLE PRECIPITATION IS EXPECTED TO REMAIN OVER THE MARINE ZONES AND POSSIBLY THE ADJACENT COASTLINE...CLOSEST TO MOISTURE CONVERGENCE WITHIN A WEAK COASTAL TROUGH. THE MAJORITY OF THE FORECAST AREA WILL SEE MOSTLY CLOUDY SKIES THROUGH THE NIGHT...KEEPING LOW TEMPERATURES IN THE UPPER 40S INLAND TO THE LOW 50S NEAR THE COAST. WEDNESDAY...THE CENTER OF THE SURFACE HIGH WILL SHIFT OFF THE NEW ENGLAND COAST...WHILE THE INLAND WEDGE STEADILY WEAKENS AND BECOMES ORIENTED ALONG THE MID ATLANTIC AND SOUTHEAST COAST. EXPECT THE TEMPERATURE GRADIENT TO BE LESS DEFINED AS A RESULT...WITH HIGHS RANGING FROM THE THE UPPER 60S TO NEAR 70 DEGREES. CLOUDS COULD LINGER FOR MUCH OF THE DAYTIME PERIOD...ESPECIALLY INLAND...WHILE RAIN CHANCES REMAIN LESS THAN A MENTIONABLE 15 PERCENT. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... THE UPPER PATTERN BECOMES MORE AMPLIFIED LATE IN THE WEEK INTO THE WEEKEND THOUGH THE COLD AIR REMAINS WELL TO THE NORTH. CANADIAN HIGH PRESSURE WILL CONTINUE TO TRY TO WEDGE DOWN THE EASTERN SEABOARD BUT WITH A BUILDING 850 MB RIDGE AND LACK OF MOISTURE OR FORCING TO PRODUCE PRECIPITATION...TEMPERATURES WILL STAY NEAR NORMAL ALBEIT WITH GREATER CLOUD COVER. HIGHS WILL GENERALLY BE IN THE MID/UPPER 60S WITH LOWS IN THE MID/UPPER 40S. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... BIGGEST CONCERN IS FOR DENSE FOG TO AFFECT THE TERMINALS OVERNIGHT INTO MID MORNING. OUR CONFIDENCE REMAINS HIGHEST AT KSAV WHERE VSBYS MAY DROP TO LESS THAN 1/4SM WITH VERTICAL VISIBILITIES 100 FT OR LESS LATER TONIGHT. CONFIDENCE IS NOT AS HIGH AT KCHS...BUT MODELS CONTINUE TO TREND WITH LOWER CONDITIONS. ON THE 06Z TAF RELEASE...WE MAINTAINED TRENDS SET FROM THE PREVIOUS CYCLE BUT SLIGHT DIFFERENCES IN THE LOWEST LEVEL THERMAL/MOISTURE PROFILES FROM LAST NIGHT HAVE BEEN NOTED WITH UNCERTAINTY IN HOW THESE SUBTLETIES COME INTO PLAY....IF AT ALL. FOG WILL BURN OFF BY 15Z AT BOTH TERMINALS AND THEN VFR THROUGH 06Z TUESDAY. EXTENDED AVIATION OUTLOOK...VISIBILITY RESTRICTIONS ARE POSSIBLE IN FOG LATE MON NIGHT AND EARLY TUESDAY. MVFR OR LOWER CEILINGS ARE POSSIBLE TUESDAY INTO WEDNESDAY DUE TO LOW-LEVEL MOISTURE IN THE WAKE OF THE COLD FRONT. VISIBILITY AND/OR CEILING RESTRICTIONS POSSIBLE THURSDAY MORNING. && .MARINE... OVERNIGHT...VARIABLE WINDS 5 KT OR LESS WITH SEAS 1-2 FT WILL DOMINATE THE WATERS TONIGHT. AREAS OF FOG ARE LIKELY NEAR THE COAST WITH VSBYS 1-3 NM...LOCALLY LESS THAN 1 NM. IN THE CHARLESTON HARBOR...VSBYS COULD DROP TO LESS THAN 1/2 NM. A MARINE DENSE FOG ADVISORY MAY VERY WELL BE NEEDED OVERNIGHT. MONDAY THROUGH FRIDAY...WEAK HIGH PRESSURE WILL PERSIST INTO MONDAY. A BACKDOOR COLD FRONT WILL THEN DESCEND INTO THE WATERS TUESDAY...WITH A WEDGE OF HIGH PRESSURE BUILDING IN FROM THE NORTH AND TIGHTENING THE GRADIENT WITHIN WEAK COLD ADVECTION. MARGINAL SMALL CRAFT ADVISORY CONDITIONS ACROSS THE OFFSHORE WATERS ARE POSSIBLE TUESDAY NIGHT...MAINLY FOR SEAS BUILDING TO 6 FT OVER OFFSHORE GEORGIA WATERS TUESDAY NIGHT THROUGH MIDDAY WEDNESDAY. THEREAFTER...THE GRADIENT RELAXES QUITE A BIT...AND THE POSSIBILITY FOR ADDITIONAL ADVISORIES WANES LATE IN THE WEEK. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && $$ NEAR TERM... SHORT TERM... LONG TERM... AVIATION... MARINE...
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1156 PM CST SUN NOV 30 2014 .AVIATION... FOR THE 01/06Z TAFS...LOW CLOUDS WILL CONTINUE TO MOVE IN THE REGION FROM THE WEST...BUT VFR CONDITIONS WILL REMAIN AT ALL SITES THROUGH MOST OF THE OVERNIGHT PERIOD. CIGS AND VISIBILITIES WILL LOWER NEAR DAYBREAK CREATING MVFR CONDITIONS AS A COLD FRONT MOVES THROUGH THE AREA. SHWRS ARE POSSIBLE ALONG THE FRONT. WINDS WILL REMAIN FROM THE SOUTH BETWEEN 5-10 KTS OVERNIGHT...BUT WILL SHIFT TO THE NW FOLLOWING FRONTAL PASSAGE. && .PREV DISCUSSION... /ISSUED 1001 PM CST SUN NOV 30 2014/ DISCUSSION... SOME CHANGES WERE NECESSARY OVERNIGHT AS WELL AS MONDAY GIVEN A SLIGHTLY FASTER FRONTAL MOVEMENT. THE LEADING EDGE OF MUCH COLDER AIR IN THE FORM OF A STRONG COLD FRONT WAS LOCATED NEAR A HRO...FSM...DUA...RPH LINE AS OF 03Z. A 20 TO 25 DEGREE TEMPERATURE DROP EXISTS DIRECTLY BEHIND THIS BOUNDARY WHICH WAS OUTPACING OUR PREVIOUS FORECAST SLIGHTLY. THE OUACHITAS WILL LIKELY SLOW THIS BOUNDARY UP SLIGHTLY BUT STILL FEEL LIKE THE FASTER FRONTAL MOVEMENT VIA THE HRRR WARRANTED AN UPDATE THIS EVENING. CLOUD COVER IS PATCHY ATTM BUT SHOULD CONTINUE TO DEVELOP THROUGH THE OVERNIGHT HOURS AND THIS WILL BE CRUCIAL AS IT PERTAINS TO OVERNIGHT LOW TEMPERATURES...NOT TO MENTION JUST WHERE THE COLD FRONT IS EXPECTED TO BE BY 8 AM IN THE MORNING. BY 13Z...EXPECT THE FRONT TO BE NEAR OR JUST EAST OF A TYR...TO DEQ LINE...LIKELY BULGING OUT SLIGHTLY ACROSS THE NORTHERN HALF OF NE TX GIVEN THE BLOCKING INFLUENCE OF THE OUACHITAS. WINDS HAVE DECOUPLED PRETTY MUCH AREAWIDE THIS EVENING...BUT ESPECIALLY ACROSS OUR SE ZONES AND THIS IS WHERE PATCHY DENSE FOG WILL BECOME A POSSIBILITY IF THE CLOUD COVER TAKES ITS TIME IN FORMING. IF THIS FOG DEVELOPS...TEMPERATURES COULD FALL BELOW THEIR DEWPOINTS WHICH ALSO MAKES THIS A CHALLENGING FORECAST AS IT PERTAINS TO OVERNIGHT MIN TEMPS. RAISED TEMPERATURES SLIGHTLY ALONG A LFK...SHV...ELD LINE BUT COOLED TEMPERATURES JUST WEST OF THIS LINE AS THIS IS WHERE THE COLD FRONT IS EXPECTED TO BE BY 8 AM MON. COLD FRONT WILL LIKELY SLOW UP A BIT AS IT MOVES THROUGH NORTHERN LA ON MONDAY BUT STILL FEEL LIKE MAX TEMPS WILL BE REACHED DURING THE MORNING HOURS MONDAY GIVEN THE STRONG COLD AIR ADVECTION BEHIND THE FRONT. HAVING SAID THIS...ALSO UPDATED HOURLY DAYTIME TEMPERATURES TO BETTER REFLECT THE FALLING DAYTIME TEMPERATURES. DID NOT MAKE MUCH IN THE WAY OF CHANGES TO POP OVERNIGHT/MONDAY AS THE HRRR IS IN GOOD AGREEMENT WITH SOME PREFRONTAL/FRONTAL AND POST FRONTAL RAIN/SHOWERS DEVELOPING LATER TONIGHT AND THROUGH THE DAY MONDAY. UPDATED ZONE PACKAGE ALREADY SENT...13 && .PRELIMINARY POINT TEMPS/POPS... SHV 61 63 38 52 47 / 20 60 30 0 10 MLU 60 73 40 53 45 / 20 60 40 10 10 DEQ 49 50 32 48 42 / 40 60 10 0 20 TXK 57 57 34 49 44 / 40 60 20 0 20 ELD 60 60 36 49 44 / 20 70 30 0 10 TYR 55 56 32 50 47 / 30 50 10 0 20 GGG 60 60 34 51 48 / 30 60 20 0 20 LFK 63 63 37 54 48 / 20 50 30 0 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 20
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1206 AM CST Mon Dec 1 2014 .UPDATE: Issued at 1157 PM CST Sun Nov 30 2014 Precipitation has become more persistent and continues to develop within an elongated SW-NE oriented moisture convergence zone stretching from northeast OK along I-44 in MO and I-70 in IL. While the coverage of precipitation is scattered in general, persistent waves of scattered precipitation are expected overnight into early Monday morning. This will occur as cold air/sub-freezing continues to intensify/spread southward resulting in freezing rain. We have also had some reports of sleet in the metro area mixing within the showers. Given the persistence, we could see some light ice accumulatons/glazing. The greatest impacts will be on untreated elevated roads - bridges and overpasses. I have issued a winter weather advisory through 600 am for the aforementioned corridor into southeast MO and southern IL. The advisory may need to be expanded past 12z for some areas. Glass Issued at 934 PM CST Sun Nov 30 2014 At this point I haven`t seen much in the latest observational and model data to suggest significant changes are need to the previous forecast. The cold front has passed through the CWA, stretching across far southern IL and southeast MO at 03z. Very spotty and very weak fast moving echoes have begun to show up on regional radars within the cold air across southern MO and southern IL, but currently south of the freezing line. These appear to be in response to isentropic lift over the shallow cold dome. The last few runs of the RAP and HRRR suggest this may be the pattern the remainder of the night and into Monday morning with these spotty small fast-moving blips of precipitation, which will eventually be occuring in the sub-freezing air as it continues to spread southward. The current chance pops appear to have this adequately covered and the only real change was to bump slightly northward the northern periphery of slight chance pops. The two inch ground temperature here at the WFO in Weldon Spring is 46 degrees, which would suggest any ice issues with this spotty ZR would be on elevated surfaces. Unless something changes, the coverage of precipitation and associated impacts would be less than needed for an advisory. We will continue to monitor closely through the overnight hours should coverage become greater than currently anticipated and then changes would be required. Glass && .SHORT TERM: (Through Monday) Issued at 229 PM CST Sun Nov 30 2014 Main focus remains precip chances thru the period. Mdls remain in fairly good agreement in most aspects. Still believe the nrn extent of mdl QPF is overdone due to issues mentioned yesterday. Mdls prog the weak s/w currently over ern TX/OK region to move newd this evening. This s/w shud arrive over the srn MO/IL and KY region about the same time as the 850mb cdfnt. This combination of low and upper level forcing shud be enuf for precip to develop. This precip shud develop around 06z tonight and persist thru much of the night. The main question is exactly where will the precip develop. Latest mdl guidance continues to suggest this will develop just SE of the CWA. However, given the uncertainty with location, will keep high chance PoPs across the far srn tier of counties. Precip type continues to be a struggle. Precip shud begin as RA and freeze as the cold air pushes swd thru the region. MO mesonet obs continue to show 4 inch soil temps in the lower 50 F range across SE MO. This shud limit ice accumulation to elevated sfcs if any does occur. That said, these elevated sfcs may also include bridges and overpasses if untreated. One chance from mdl soundings yesterday is precip may linger a bit later than prev anticipated. Latest mdl soundings suggest that if precip continues as far N as KFAM Mon morning, IP is possible. Have added mention of IP for Mon morning along the nrn edges of the precip shield, but kept PoPs low for this time. Mdls have come into better agreement regarding temps and trended twd more of a compromise for temps thru the period. Given the warm sfc temps and uncertainty where precip will develop late tonight into Mon, will hold off on issuing a headline for now. However, a headline will likely be needed if precip develops further N than currently anticipated. Tilly .LONG TERM: (Tuesday through Next Sunday) Issued at 315 PM CST Sun Nov 30 2014 Once the precip moves out of the region on Mon, the sfc ridge will quickly move thru the region and be S of the CWA by mid day Tues. With clouds clearing out, ample insolation shud allow temps to climb into the 40s. Mdls remain in fairly good agreement thru Thurs. Beyond Thurs, mdl solns diverge. The ECMWF/GEM are in better agreement regarding mass fields with a more amplified pattern late this week compared to the GFS. Have therefore trended twd a ECMWF/GEM compromise. However, have kept low PoPs lingering across much of the CWA due to the GFS soln. One change made from the prev few shifts is a switch from a RA or SN forecast to a RA or FZRA forecast. Latest GFS soundings do not support SN thru the extd portion of the forecast. Due to inconsistencies from one run to the next and differences among mdls thru the extd periods, have low confidence in any one mdl soln. However, mdls do come into better agreement for Sun and into next week as a trof ejects into the Plains. Have trended PoPs slightly higher late in the period with better mdl agreement. Tilly && .AVIATION: (For the 06z TAFs through 06z Monday Night) Issued at 1141 PM CST Sun Nov 30 2014 Widely scattered showers have developed over southern half of forecast area and are moving northeast through metro area with freezing rain and some sleet being reported. Coverage is spotty so for now kept tafs dry but did add tempo mention of mvfr cigs through 10z Monday. Rest of taf sites to remain vfr. North winds to persist with gusts at times over forecast area with vfr conditions. Winds to become northeasterly by Monday afternoon and diminish a bit. Specifics for KSTL: Widely scattered showers have developed over southern half of forecast area and are moving northeast through metro area with freezing rain and some sleet being reported. Coverage is spotty so for now kept tafs dry but did add tempo mention of mvfr cigs through 10z Monday. Otherwise, north winds to persist with gusts at times over forecast area with vfr conditions. Winds to diminish a bit by late Monday afternoon. Byrd && .LSX WATCHES/WARNINGS/ADVISORIES: MO...WINTER WEATHER ADVISORY until 6 AM CST Monday FOR Crawford MO- Franklin MO-Gasconade MO-Iron MO-Jefferson MO-Madison MO- Reynolds MO-St. Charles MO-St. Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve MO-Warren MO-Washington MO. IL...WINTER WEATHER ADVISORY until 6 AM CST Monday FOR Bond IL- Clinton IL-Madison IL-Monroe IL-Randolph IL-St. Clair IL- Washington IL. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1141 PM CST Sun Nov 30 2014 .UPDATE: Issued at 934 PM CST Sun Nov 30 2014 At this point I haven`t seen much in the latest observational and model data to suggest significant changes are need to the previous forecast. The cold front has passed through the CWA, stretching across far southern IL and southeast MO at 03z. Very spotty and very weak fast moving echoes have begun to show up on regional radars within the cold air across southern MO and southern IL, but currently south of the freezing line. These appear to be in response to isentropic lift over the shallow cold dome. The last few runs of the RAP and HRRR suggest this may be the pattern the remainder of the night and into Monday morning with these spotty small fast-moving blips of precipitation, which will eventually be occuring in the sub-freezing air as it continues to spread southward. The current chance pops appear to have this adequately covered and the only real change was to bump slightly northward the northern periphery of slight chance pops. The two inch ground temperature here at the WFO in Weldon Spring is 46 degrees, which would suggest any ice issues with this spotty ZR would be on elevated surfaces. Unless something changes, the coverage of precipitation and associated impacts would be less than needed for an advisory. We will continue to monitor closely through the overnight hours should coverage become greater than currently anticipated and then changes would be required. Glass && .SHORT TERM: (Through Monday) Issued at 229 PM CST Sun Nov 30 2014 Main focus remains precip chances thru the period. Mdls remain in fairly good agreement in most aspects. Still believe the nrn extent of mdl QPF is overdone due to issues mentioned yesterday. Mdls prog the weak s/w currently over ern TX/OK region to move newd this evening. This s/w shud arrive over the srn MO/IL and KY region about the same time as the 850mb cdfnt. This combination of low and upper level forcing shud be enuf for precip to develop. This precip shud develop around 06z tonight and persist thru much of the night. The main question is exactly where will the precip develop. Latest mdl guidance continues to suggest this will develop just SE of the CWA. However, given the uncertainty with location, will keep high chance PoPs across the far srn tier of counties. Precip type continues to be a struggle. Precip shud begin as RA and freeze as the cold air pushes swd thru the region. MO mesonet obs continue to show 4 inch soil temps in the lower 50 F range across SE MO. This shud limit ice accumulation to elevated sfcs if any does occur. That said, these elevated sfcs may also include bridges and overpasses if untreated. One chance from mdl soundings yesterday is precip may linger a bit later than prev anticipated. Latest mdl soundings suggest that if precip continues as far N as KFAM Mon morning, IP is possible. Have added mention of IP for Mon morning along the nrn edges of the precip shield, but kept PoPs low for this time. Mdls have come into better agreement regarding temps and trended twd more of a compromise for temps thru the period. Given the warm sfc temps and uncertainty where precip will develop late tonight into Mon, will hold off on issuing a headline for now. However, a headline will likely be needed if precip develops further N than currently anticipated. Tilly .LONG TERM: (Tuesday through Next Sunday) Issued at 315 PM CST Sun Nov 30 2014 Once the precip moves out of the region on Mon, the sfc ridge will quickly move thru the region and be S of the CWA by mid day Tues. With clouds clearing out, ample insolation shud allow temps to climb into the 40s. Mdls remain in fairly good agreement thru Thurs. Beyond Thurs, mdl solns diverge. The ECMWF/GEM are in better agreement regarding mass fields with a more amplified pattern late this week compared to the GFS. Have therefore trended twd a ECMWF/GEM compromise. However, have kept low PoPs lingering across much of the CWA due to the GFS soln. One change made from the prev few shifts is a switch from a RA or SN forecast to a RA or FZRA forecast. Latest GFS soundings do not support SN thru the extd portion of the forecast. Due to inconsistencies from one run to the next and differences among mdls thru the extd periods, have low confidence in any one mdl soln. However, mdls do come into better agreement for Sun and into next week as a trof ejects into the Plains. Have trended PoPs slightly higher late in the period with better mdl agreement. Tilly && .AVIATION: (For the 06z TAFs through 06z Monday Night) Issued at 1141 PM CST Sun Nov 30 2014 Widely scattered showers have developed over southern half of forecast area and are moving northeast through metro area with freezing rain and some sleet being reported. Coverage is spotty so for now kept tafs dry but did add tempo mention of mvfr cigs through 10z Monday. Rest of taf sites to remain vfr. North winds to persist with gusts at times over forecast area with vfr conditions. Winds to become northeasterly by Monday afternoon and diminish a bit. Specifics for KSTL: Widely scattered showers have developed over southern half of forecast area and are moving northeast through metro area with freezing rain and some sleet being reported. Coverage is spotty so for now kept tafs dry but did add tempo mention of mvfr cigs through 10z Monday. Otherwise, north winds to persist with gusts at times over forecast area with vfr conditions. Winds to diminish a bit by late Monday afternoon. Byrd && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1200 AM EST MON DEC 1 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE REGION OVERNIGHT WITH RAIN SHOWERS SHIFTING FROM WESTERN INTO CENTRAL NEW YORK FOLLOWED BY MUCH COOLER TEMPERATURES MONDAY. TEMPERATURES WILL WARM BACK TOWARDS AVERAGE BY MIDWEEK AS A WARM FRONT LIFTS NORTH...BRINGING WITH IT A CHANCE FOR FREEZING RAIN TUESDAY NIGHT. THE SEE SAW CONTINUES WEDNESDAY AS ANOTHER COLD FRONT SWINGS ACROSS THE AREA...BRINGING ANOTHER ROUND OF COOL BUT MAINLY DRY WEATHER THAT WILL LAST THROUGH THE REMAINDER OF THE WORK WEEK. && .NEAR TERM /THROUGH TODAY/... A COLD FRONT EXTENDS FROM THE SAINT LAWRENCE VALLEY SOUTHWEST TO ROCHESTER THEN ON TO COLUMBUS LATE THIS EVENING. REGIONAL RADARS CONTINUE TO SHOW A THIN BAND OF RAIN SHOWERS JUST AHEAD OF THE FRONT WHICH EXTENDS FROM WATERTOWN TO JUST EAST OF ROCHESTER THEN SOUTHWEST TO COLUMBUS. THE FRONTS PARALLEL ORIENTATION WITH THE 500MB FLOW WILL KEEP A SLOW MOVEMENT EAST ACROSS THE REGION OVERNIGHT. THE EARLIER BLEND OF QPF FROM RECENT HRRR AND LOCAL WRF RUNS CONTINUE TO WORK OUT VERY WELL. STILL EXPECT THE FRONT TO EASE TO EASTERN NEW YORK BY 12Z. THE QPF BLEND YIELDS 0.10-0.25 INCH OF RAINFALL. TEMPERATURES AHEAD OF THE FRONT CONTINUE TO RANGE THROUGH THE 50S TO AROUND 60 LATE THIS EVENING AND ARE FALLING INTO THE 40S BEHIND THE FRONT. THESE DROPPING TEMPS WILL CONTINUE BEHIND THE FRONT AS IT SHIFTS EAST AND COLD ADVECTION TAKES HOLD...TEMP TRENDS REMAIN IN LINE WITH RGEM. READINGS ACROSS WESTERN NEW YORK WILL FALL INTO THE MID 30S BY DAYBREAK WITH LOWER 40S ACROSS THE EASTERN HALF OF THE FORECAST AREA. COLD AND DRY AIR WILL CONTINUE TO POUR ACROSS THE LOWER GREAT LAKES ON MONDAY WITH EARLY MORNING HIGHS FALLING INTO THE UPPER 20S TO MID 30S...WITH COOLEST READINGS ACROSS HIGHER TERRAIN...BY LATE IN THE DAY. THE DRY ARCTIC AIRMASS WILL PRECLUDE THE DEVELOPMENT OF ANY SIGNIFICANT LAKE EFFECT PRECIPITATION ACROSS THE FORECAST AREA...THOUGH LAKE-EFFECT CLOUDS WILL BE IN ABUNDANCE ALONG WITH PERHAPS A FEW FLURRIES ACROSS UPSLOPE AREAS DOWNWIND OF BOTH LAKES. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... MONDAY NIGHT A SURFACE RIDGE OF HIGH PRESSURE WILL BE ADVANCING FROM THE WESTERN GREAT LAKES TOWARDS SOUTHERN QUEBEC BY TUESDAY MORNING. THIS FEATURE WILL BE RESPONSIBLE FOR DRIER AIR FLOWING ACROSS THE EASTERN GREAT LAKES MONDAY NIGHT...AS WELL AS VEERING WINDS FROM NORTHWEST TO NORTHEAST. A FEW LAKE EFFECT FLURRIES WITHIN THE DRYING ATMOSPHERE EARLY MONDAY NIGHT WILL DISSIPATE ALONG THE INLAND SOUTHERN SHORELINE THROUGH THE EVENING HOURS. OTHERWISE CLEARING SKIES COUPLED WITH A FRESH COLD AIRMASS ASSOCIATED WITH THIS HIGH PRESSURE WILL BRING LOWS IN THE TEENS...TO SINGLE DIGITS ACROSS THE NORTH COUNTRY. TUESDAY EXPECT A COLD START TO THE DAY WITH MORNING SUNSHINE FADING BEHIND THICKENING CIRRUS THAT WILL BE APPROACHING FROM THE SOUTH. MODELS ARE A LITTLE QUICKER WITH THE RETURN FLOW OF MOISTURE BEHIND THIS AREA OF HIGH PRESSURE. THIS WILL LIMIT THE EARLY EVENING COOLING SOME AND LIKELY CONFINE THE FREEZING RAIN POTENTIAL TO MORE OF THE HILLS OF SW NYS AND THE NORTH COUNTRY. PRECIPITATION IS EXPECTED TO ARRIVE ALONG THE LEADING EDGE OF A 55 KNOT LLJ LATER TUESDAY NIGHT AFTER THE DRY BOUNDARY LAYER SATURATES. BY WEDNESDAY MIDDAY SUFFICIENT WARMING ALOFT SHOULD ALLOW FOR JUST PLAIN RAIN SHOWERS TO PASS ACROSS THE REGION...WITH CHANCES LESSENING TOWARDS THE WEST AS A COLD FRONT SENDS THE MAIN SURGE OF MOISTURE EASTWARD OVER EASTERN NEW YORK STATE. WEDNESDAY NIGHT BEHIND THE COLD FRONT LAKE PARAMETERS WILL INCREASE TO SUPPORT LAKE EFFECT SNOW ON A WESTERLY FLOW. WHILE FLURRIES MAY FLY ACROSS SW NYS...THE WESTERLY FLOW ALONG THE LONG LAKE ONTARIO AXIS WITH A FAIR CAPPING INVERSION OF 5K FEET MAY ALLOW FOR MINOR LAKE EFFECT SNOW ACCUMULATIONS ON THE TUG HILL. BEHIND THE COLD FRONT WEDNESDAY NIGHT TEMPERATURES WILL DROP BACK INTO THE 20S...BUT WITH A ZONAL FLOW ALOFT...AND ARCTIC AIR LACKING A SIGNIFICANT DROP IN TEMPERATURES IS NOT LIKELY. && .LONG TERM /THURSDAY THROUGH SUNDAY/... THURSDAY A VIGOROUS SHORTWAVE WILL BE ADVANCING ACROSS SOUTHERN CANADA...BUT SHOULD REMAIN FAR ENOUGH NORTH TO ALLOW FOR A DRY DAY SOUTH OF LAKE ONTARIO...AND JUST SLIGHT CHANCE POPS ACROSS THE SAINT LAWRENCE VALLEY FOR A FEW PASSING SNOW SHOWERS. ALSO SE OF LAKE ONTARIO FLURRIES AND LIGHT LAKE EFFECT SNOW SHOWERS MAY STILL BE FALLING AT THE START OF THE DAY...BUT AS DRIER AIR FILTERS INTO THE LAKE EFFECT ACTIVITY...ALL SNOW SHOWERS SHOULD END THROUGH THE EARLY PART OF THE DAY. BEHIND THIS SHORTWAVE...A ZONAL FLOW WILL DOMINATE WITH TEMPERATURES AVERAGING AROUND NORMAL. A SHORTWAVE WITHIN THIS ZONAL FLOW MAY BRING A MIXTURE OF RAIN/SNOW LATER FRIDAY NIGHT AND SATURDAY...THOUGH WITH MODEL DIFFERENCES (GFS MUCH SLOWER WITH THE SHORTWAVE AND PRECIPITATION) WILL JUST CONTINUE WITH LOW CHANCE/SLIGHT CHANCE POPS FOR NEXT WEEKEND. && .AVIATION /05Z MONDAY THROUGH FRIDAY/... MVFR CIGS ARE FOUND WIDESPREAD AT 05Z WITH A COLD FRONT CROSSING FROM WESTERN INTO CENTRAL NEW YORK. RADAR IS SHOWING A BAND OF RAIN SHOWERS EXTENDING ALONG THE FRONT FROM KART TO EAST OF KROC TO COLUMBUS. RAIN SHOWERS AND COLD ADVECTION HAVE BROUGHT SOME TEMPO LOWERING OF CIGS ALTHOUGH CONFIDENCE FOR EXTENDED IFR REMAINS LOW BASED ON OBS UPSTREAM AND BUFKIT PROFILES. FLOW IS VEERING WESTERLY BEHIND THE FRONT WITH A NOMINAL IMPROVEMENT TO VFR...WITH MVFR ACROSS HIGHER ELEVATIONS EXPECTED...THROUGH THE POST SUNRISE HOURS. A SLIGHT CHANCE OF SOME WEAK LAKE EFFECT SNOW IS POSSIBLE SOUTHEAST OF THE LAKES DURING THE DAY MONDAY. CIGS BECOME ALL VFR BY MONDAY EVENING AS HIGH PRESSURE NOSES ACROSS THE LOWER GREAT LAKES. OUTLOOK... MONDAY NIGHT THROUGH TUESDAY...VFR. WEDNESDAY...MAINLY VFR WITH A CHANCE OF SHOWERS. THURSDAY...VFR/MVFR. && .MARINE... WEST-NORTHWEST FLOW IS DEVELOPING BEHIND A COLD FRONT CROSSING THE LOWER GREAT LAKES OVERNIGHT. INCREASING FETCH AND COLD ADVECTION WILL ALLOW WAVES TO BUILD ON LAKE ONTARIO TONIGHT INTO MONDAY...RESULTING IN WIDESPREAD SMALL CRAFT ADVISORIES ON THAT LAKE WHILE ON LAKE ERIE THE SHORTER FETCH NORTHWESTERLY FLOW SHOULD KEEP WINDS/WAVES JUST UNDER SCA CRITERIA. WAVES WILL BUILD INTO THE 5 TO 7 FOOT RANGE BY LATE IN THE DAY MONDAY ALONG THE SOUTH SHORE OF LAKE ONTARIO BEFORE DIMINISHING LATER MONDAY NIGHT AS HIGH PRESSURE MOVES OVERHEAD. A BRIEF PERIOD OF SMALL CRAFT CONDITIONS WILL RETURN WEDNESDAY AFTERNOON AS ANOTHER COLD FRONT SWEEPS ACROSS THE LAKE FOLLOWED BY ANOTHER HIGH THURSDAY. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR LEZ040- 041. SMALL CRAFT ADVISORY UNTIL 7 AM EST TUESDAY FOR LOZ043-044. SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR LOZ042. SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR LOZ045. && $$ SYNOPSIS...SMITH/WOOD NEAR TERM...SMITH/WOOD SHORT TERM...THOMAS LONG TERM...THOMAS AVIATION...SMITH/WOOD MARINE...SMITH/WOOD
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1237 AM EST MON DEC 1 2014 .SYNOPSIS... HIGH PRESSURE WILL EXTEND OVER THE AREA FROM OFFSHORE THROUGH MONDAY. A BACKDOOR COLD FRONT WILL MOVE THROUGH THE AREA MONDAY NIGHT WITH HIGH PRESSURE BUILDING IN FROM THE NORTH TUESDAY THROUGH LATE WEEK. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1230 AM MON...MAINLY CLR SKIES WILL CONT WITH HIGH PRES OFF THE CST. WINDS WILL BRIEFLY DECOUPLE AT TIMES INLAND OVERNIGHT ALLOWING LOW TEMPS TO REACH MAINLY LOW TO MID 40S. BRZ WILL PERSIST ALONG THE BEACHES KEEPING TEMPS UP A BIT WITH MAINLY UPR 40S TO MID 50S. WL CONT TO KEEP PATCHY FOG IN LATE SRN TIER PER HIGH RESOLUTION MODELS LIKE THE HRRR AND NARRE SHOWING FOG/ST DEVELOPING IN THIS AREA. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 AM TUESDAY/... AS OF 230 PM SUNDAY...HIGH PRESSURE OFFSHORE WILL SLOWLY SUPPRESS AS A TROUGH APPROACHES THE APPALACHIANS BY MONDAY AFTERNOON. THIS WILL YIELD SOUTHERLY FLOW FROM THE SURFACE TO THE UPPER LEVELS. AMPLE DRY AIR WILL BE IN PLACE AND THE ONLY SATURATION NOTED IN THE UPPER LEVELS...SO EXPECTING MOSTLY SUNNY CONDITIONS WITH FILTERED CIRRUS. AS A RESULT OF BOTH CLEAR SKIES AND SOUTHERLY FLOW...THICKNESS VALUES WILL REFLECT HIGHS IN THE MID/UPPER 60S WITH SOME LOCATIONS TOPPING OUT AOA 70 DEGREES. && .LONG TERM /TUESDAY THROUGH MONDAY/... AS OF 303 PM SUNDAY...A BACK DOOR FRONT WILL DROP INTO THE REGION LATE MONDAY NIGHT INTO TUESDAY MORNING. SOME TIMING DISAGREEMENT STILL EXISTS AMONGST MEDIUM RANGE GUIDANCE WITH GFS ABOUT 6 HOURS FASTER THAN THE ECM/NAM SO CONTINUED FOLLOWING SUITE WITH PREVIOUS FCST. WHILE MOST OF THE DEEPER MOISTURE AND VORTICITY REMAIN TO OUR NORTH...WILL MAINTAIN SLIGHT CHANCE POPS THROUGH TUESDAY ENDING TUESDAY EVENING FOR NORTHERN ZONES. TUESDAY WILL BE MUCH COOLER THAN MONDAY AS IN- SITU CAD EVENT DEVELOPS...WITH HIGHS IN THE 50S AREA- WIDE...STRUGGLING TO REACH 50 ACROSS THE COASTAL PLAIN COUNTIES. SOUNDINGS AND SYNOPTIC PATTERN SUGGEST STRONG FRONTAL INVERSION IN PLACE THROUGH THE DAY TUESDAY WITH DEEP LOW LEVEL MOISTURE IN PLACE WITH MAINLY CLOUDY 1-1.5 K FT STRATUS LAYER. HAVE ADDED PATCHY DRIZZLE TO GRIDS...ESP NORTHERN/WESTERN ZONES WHERE LOW LEVEL MOISTURE IS DEEPEST. DO NOT EXPECT ANY MEASURABLE PRECIP PER DISCUSSION ABOVE. FROM MID THROUGH LATE NEXT WEEK...WE REMAIN IN A GENERALLY W/SW FLOW ALOFT WITH NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES. WEDNESDAY AND THURSDAY SHOULD BE DRY. ANOTHER WEAK SURFACE COLD FRONT WILL CROSS THE AREA LATE THURSDAY SHIFTING WINDS NE THEN THE COLD FRONT WASHES OUT THURSDAY NIGHT INTO FRIDAY. A SERIES OF WEAK SHORTWAVES WILL CROSS NORTH OF THE AREA THURSDAY INTO FRIDAY SO HAVE MAINTAINED THE SLIGHT CHANCE POPS. LATEST 30/12Z ECMWF CONTINUES TO DEVELOP A WEAK WAVE OF LOW PRESSURE ALONG THE NC COAST THIS WEEKEND AS A STRONG SHORTWAVE MOVES THROUGH VA/NC. MAX TEMPS WILL BE NEAR TO SLIGHTLY ABOVE NORMAL FOR EARLY DECEMBER FRI THROUGH THE WEEKEND...WITH READINGS GENERALLY IN THE UPPER 50S TO LOWER 60S. && .AVIATION /05Z MONDAY THROUGH FRI/... SHORT TERM /THROUGH MONDAY NIGHT/... AS OF 1230 AM MON...HIGH RES MODELS CONT TO SHOW ST/FOG DEVELOPING SRN TIER LATE TONIGHT. WITH OAJ ALREADY BOUNCING DOWN A BIT WILL HIT FOG/ST A BIT HARDER HERE WITH SOME IFR POSS AT TIMES LATE TONIGHT. MDLS DONT SHOW MUCH FURTHER N SO WILL KEEP OTHER TAFS VFR. HIGH CONFIDENCE IN A VFR FORECAST MID MONDAY MORNING THRU MON EVENING AS HIGH PRES CONTS OFFSHORE WITH MCLR SKIES. LATE MON EVENING AND OVERNIGHT A COLD FRONT WILL DROP S THRU THE REGION AND MAY SEE SOME SUB VFR CIGS DEVELOP LATE ESPCLY INLAND AND N. LONG TERM /TUE THROUGH FRI/... AS OF 3 PM SUNDAY...A BACK DOOR COLD FRONT MAY LEAD TO SOME DRIZZLE OR VERY LIGHT RAIN ON TUESDAY...THOUGH EXPECT BIGGEST IMPACT TO AVIATION LOW STRATUS IN MVFR TO POSSIBLE ISOLATED IFR CIGS AT TIMES. VFR EXPECTED TO RETURN AGAIN WED THROUGH LATE WEEK. && .MARINE... SHORT TERM /THROUGH MONDAY/... AS OF 1230 AM MON...DIAMOND BUOY HAS BOUNCED UP TO 6 FEET PAST CPL HOURS HOWEVER SEEMS LOCALIZED WITH WINDS CLOSER TO CST MUCH LIGHTER. WINDS SHLD BE PEAKING NOW FAR OUTER WTRS SO WILL NOT ISSUE SCA FOR CNTRL WTRS AND CONT TO MONITOR TRENDS. PREV DISC...SWLY FLOW CAN BE EXPECTED THROUGH THE PERIOD AS THE APPROACHING COLD FRONT CROSSES THE REGION MONDAY NIGHT. WINDS WILL PEAK TONIGHT AND RELAX A BIT ON MONDAY. EXPECTED WINDS TONIGHT WILL BE 15-20 KTS DIMINISHING TO TO 10-15 KTS BY MONDAY AFTERNOON. SEAS WILL BE 2 TO 4 FT WITH SOME 5 FOOT SETS OVER THE OUTER WATERS. SEAS WILL DIMINISH TO 2 TO 3 BY MONDAY EVENING AHEAD OF THE COLD FRONT. LONG TERM /MONDAY NIGHT THROUGH FRI/... AS OF 303 PM SUNDAY...BACK DOOR COLD FRONT CROSSES THE REGION LATE MONDAY NIGHT AND EXPECT A DRAMATIC INC IN WINDS TO NE AT 15-25 KNOTS AND SEAS BUILDING 6-7 FEET PER LOCAL NWPS/SWAN AND SUPPORTED BY THE 00Z WAVEWATCH. GREATEST THREAT FOR SCA WILL BE THE NORTHERN AND CENTRAL WATERS. WINDS/SEAS DIMINISH WEDNESDAY INTO THURSDAY. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...NONE. && $$ SYNOPSIS...JBM NEAR TERM...RF SHORT TERM...JME/LEP LONG TERM...TL AVIATION...RF/TL MARINE...RF/JME/TL/LEP
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1144 PM CST SUN NOV 30 2014 .UPDATE... ISSUED AT 1136 PM CST SUN NOV 30 2014 THE LATEST TEMP CURVE IS ON TRACK AND NO CHANGES WILL BE MADE FOR 1 AM UPDATE. SEE AVIATION DISCUSSION BELOW FOR 06Z TAFS. UPDATE ISSUED AT 945 PM CST SUN NOV 30 2014 FORECAST CHALLENGE FOR TONIGHT WILL BE TEMPERATURES. THE BIAS CORRECTED NAM12 00Z RUN VERIFIED WITH 03Z OBS BETTER THAN OTHER MODELS...WITH MOST MODELS IN THE BALL PARK BUT THE HRRR A BIT WARMER AND GFS SIGNIFICANTLY WARMER. THEREFORE WILL BUILD NOCTURNAL CURVE FROM NAM GUIDANCE...WHICH ENDS UP BEING A BIT WARMER IN THE FAR EAST AND COLDER IN THE NORTHWEST. MAIN IMPACT ON HEADLINES IS IT BRINGS THE SOUTHERN TIER OF COUNTIES INTO WIND CHILL ADVISORY CRITERIA A FEW HOURS LATER...BUT WILL KEEP HEADLINES AS THEY ARE EXPECTING A QUICK DROP ONCE THE WINDS LET UP SOME. TOMORROW MORNING...LANGDON AREA COULD MAKE IT INTO THE 40S BELOW (WIND CHILL) BUT NOT WIDESPREAD ENOUGH TO WARRANT UPGRADING SUCH A SMALL AREA TO WIND CHILL WARNING. UPDATE ISSUED AT 658 PM CST SUN NOV 30 2014 SURFACE HIGH IS CURRENTLY OVER EASTERN MT...WITH WEST SOUTHWEST WINDS ACROSS NORTH DAKOTA. TEMPERATURES ACROSS THE NORTH HAVE DROPPED A FEW DEGREES BELOW FREEZING AND WITH THE BREEZY WINDS...WIND CHILLS HAVE FALLEN TO 25 TO 30 BELOW ZERO IN PORTIONS OF EASTERN NORTH DAKOTA. TIMING OF CURRENT HEADLINES IS IN GOOD SHAPE AND NO CHANGES PLANNED TO ONGOING FORECAST OR HEADLINES. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 300 PM CST SUN NOV 30 2014 MAIN CHALLENGES WILL BE WINDS AND TEMPS AND THE RESULTING WIND CHILL READINGS. AS OF MID AFTERNOON SKIES HAD COMPLETELY CLEARED OUT WITH GUSTY WEST WINDS. DESPITE HAVING A LITTLE SNOW ON THE GROUND...THE WEST WINDS AND SUN HAVE ALLOWED TEMPS TO RISE ABOVE ZERO JUST ABOUT EVERYWHERE. STILL EXPECTING THE WAVE NEARING THE MANITOBA LAKES REGION TO SWING THRU THE AREA TONIGHT...BUT NOT SEEING ANY CLOUDS ASSOCIATED WITH IT. THEREFORE WILL STICK WITH A CLEAR FORECAST. THERE ARE SOME COLDER TEMPS ASSOCIATED WITH THE WAVE WHICH WILL CAUSE STEADY COLD ADVECTION THRU THE EVENING. THIS SHOULD RESULT IN STEADY WEST TO NW WINDS AT LEAST THRU MIDNIGHT...AND POSSIBLY EVEN BEYOND. THINK AS THE SFC HIGH BUILDS INTO SOUTHEAST ND TOWARD 12Z MON WINDS WILL FINALLY DROP OFF. THIS WILL PROBABLY ALLOW A RAPID TEMP FALL SO WILL STICK WITH LOWS TONIGHT IN THE 15 TO 20 BELOW ZERO RANGE. ALREADY ISSUED A WIND CHILL ADVISORY FOR THE ENTIRE FA UNTIL MID TO LATE MON MORNING. ONE ISSUE TO CONSIDER IS REACHING WIND CHILL WARNING CRITERIA OR WIND CHILL READINGS 40F BELOW OR COLDER. CURRENT FORECAST SHOWS THE NORTHWEST FA GETTING CLOSE BUT WITH UNCERTAINTIES IN HOW FAST WINDS WILL DROP OFF AND THE RESULTING TEMPS THINK AN ADVISORY IS GOOD FOR NOW. EXPECT LOTS OF SUN AGAIN ON MONDAY WITH WINDS TURNING AROUND TO THE SOUTH. BY AFTERNOON INTO MON EVENING PRETTY GUSTY SOUTH WINDS EXPECTED. COMBINATION OF WINDS AND WARM ADVECTION WILL KEEP TEMPS WARMER MON NIGHT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 300 PM CST SUN NOV 30 2014 MODELS HAD BEEN SHOWING A WEAK BAND OF LIGHT SNOW MOVING ALONG THE ND/SD BORDER ON TUE/TUE NIGHT. GFS/ECMWF HAVE BACKED OFF ON THIS WHILE NAM/GEM KEEP SOME SEMBLANCES OF IT AROUND. WITH THE UNCERTAINTY NOW WILL GO WITH A DRY FORECAST. MODELS ALSO HAVE A LITTLE LIGHT SNOW DROPPING TOWARD THE NORTHEAST FA 12Z-18Z WED. FOR NOW KEPT IT DRY TOO AND WILL SEE WHAT LATER RUNS BRING. WEDNESDAY NIGHT-SUNDAY...MODELS IN DECENT AGREEMENT WITH OVERALL TRENDS. NORTHWEST FLOW ALOFT WILL TRANSITION TO ZONAL FLOW THROUGH THIS PERIOD. NO STRONG SIGNALS FOR PRECIPITATION FROM ANY MODEL...AND HAVE GONE WITH A DRY FORECAST. WITH THAT SAID...THERE COULD BE A LOW PREDICTIVE EVENT...BUT THESE TYPES OF EVENTS USUALLY HAVE MINIMAL IMPACT. TEMPERATURE WILL BE THE MAIN CHALLENGE...LIKELY TRANSITIONING TO ABOVE NORMAL VALUES BY THE WEEKEND (AND WITH MINIMAL SNOW COVER THE QUESTION WILL BE HOW WARM FOR MAX TEMPS). && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1136 PM CST SUN NOV 30 2014 WINDS CONTINUE TO GUST IN THE DVL AREA AND NORTHERN VALLEY...BUT WINDS WEST OF RUGBY ARE BEGINNING TO SUBSIDE. WILL EXTEND THE BREEZY W SW WINDS ANOTHER TWO TO THREE HOURS. OTHER THAN THAT...CLEAR SKIES WITH WINDS SHIFTING TO A SOUTHERLY COMPONENT LATE MONDAY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR NDZ038-039-049- 052-053. WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR NDZ006>008-014>016- 024-026>030-054. MN...WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR MNZ003-024- 027>032-040. WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR MNZ001-002-004>009- 013>017-022-023. && $$ UPDATE...SPEICHER SHORT TERM...GODON LONG TERM...GODON/TG AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1235 AM EST MON DEC 1 2014 .SYNOPSIS... A SHARP COLD FRONT WILL SAG THROUGH THE OHIO VALLEY TONIGHT. LIGHT RAIN WILL ACCOMPANY THIS FRONT FOR MOST LOCATIONS...AS WELL AS A TWENTY DEGREE TEMPERATURE DROP IN THE FIRST FEW HOURS AFTER IT PASSES. THE FRONT WILL SLOW A LITTLE ON ITS SOUTHWARD TREK ON MONDAY AS IT SAGS INTO VIRGINIA AND TENNESSEE...AND WEAK DISTURBANCES SHIFTING NORTHEAST ALONG THE FRONT MONDAY AFTERNOON AND EVENING WILL LINGER RAIN ACROSS PORTIONS OF SOUTHERN OHIO AND NORTHERN KENTUCKY. A LITTLE LIGHT SNOW MAY MIX IN ACROSS THIS AREA BEFORE PRECIPITATION ENDS MONDAY NIGHT. TEMPERATURES WILL BE MUCH COLDER ON MONDAY INTO TUESDAY...BEFORE THE FRONT RETURNS NORTHWARD BY MIDWEEK WITH MILD AIR AND A RETURNING THREAT FOR LIGHT RAIN SHOWERS. && .NEAR TERM /THROUGH TODAY/... LATEST SFC ANALYSIS SHOWS COLD PUSHING INTO NW OHIO FROM JUST WEST OF TO JUST NW OF DAY. NARROW BAND OF LIGHT RAIN SHOWERS INVOF OF THIS BOUNDARY ASSOCIATED WITH FAVORABLE LOW LEVEL MOISTURE CONVERGENCE. THIS AXIS OF PRECIPITATION TO SAG SOUTH THRU ILN/S FA WITH THE FRONT OVERNIGHT. HAVE ALLOWED PCPN TO EXPAND SOME NORTH OF THE BOUNDARY LATE TONIGHT AS MORE FAVORABLE 850 MB CONVERGENCE COMES INTO PLAY. STRONG COLD AIR ADVECTION WITH TEMPERATURES ALREADY DROPPING INTO THE MID/UPR 40S OVER NW OHIO. HAVE MADE SLIGHT ADJUSTMENT TO HOURLY TEMPERATURES ALLOWING FOR QUICKER PUSH OF COLD AIR. EXPECT LOWS BY MORNING TO RANGE FORM THE LOWER 30S NW TO THE MID 40S SE. PREV DISCUSSION... OVERLAYING YESTERDAY/S FORECAST SOUNDINGS VALID 30.12Z AT ILN WITH ILN RAOB AS VERIFICATION HAS SHOWN THAT NWP GUIDANCE HAS VASTLY OVERESTIMATED MIXING RATIOS/SATURATION BELOW 900MB LAST NIGHT THROUGH TODAY. THUS...DEPTH OF LOW LEVEL SATURATED LAYER HAS REMAINED ABOUT 1KM TO 1.2KM DEEP FROM LATE LAST NIGHT THROUGH MUCH OF THE DAY AND HAS KEPT DZ/RA-- PRODUCTION AT BAY THUS FAR. WOULD MUCH PREFER TO SEE THE SATURATED LAYER EXCEED 1.5KM AND CLOSER TO 2.0KM FOR A LOW LEVEL SATURATED LAYER TO PRODUCE -DZ/RA-- IN THE ABSENCE OF STRONGER LOW LEVEL SHORTWAVE TROUGH OR LOWER 100MB BOUNDARY LIKE WHAT WE HAVE IN THE OPEN WARM SECTOR TODAY. CLOUD CIGS REMAIN STUBBORNLY IN THE 2-3KFT LAYER AGL SO WE/VE BEEN PROGRESSIVELY DELAYING MEASURABLE RAIN THREATS. THIS HAS ALLOWED FOR EVEN WARMER READINGS /MANY LOCATIONS IN MID 60S/ AND DWPTS HAVE CHECKED IN ABOUT 5F-7F LOWER...STRUGGLING TO BREACH 50F...THUS T/TD SPREADS ARE > 10F MOST LOCATIONS. ALL THAT STARTING TO CHANGE HOWEVER AS SHARP/ARCTIC COLD FRONT APPROACHES AND GLANCING BLOW FROM PARENT HEIGHT FALLS SWEEPING ALONG THE US/CANADIAN BORDER IS FORCING A GRADUAL INCREASE IN SYNOPTIC ASCENT ACROSS THE GREAT LAKES. KIWX WSR-88D HAS RECENTLY DEPICTED BLOSSOMING ECHOES AHEAD OF THE COLD FRONT WHICH WAS DEPICTED AT 30.18Z TO RUN FROM GRAND RAPIDS /MI/ TO CHICAGO TO SPRINGFIELD /IL/. THE FURTHER SOUTH/WEST YOU TRAVEL ALONG THE FRONT IN IL/MO/OK...THE SHARPER THE TEMP GRADIENT /30F ACROSS ONE OR TWO COUNTIES IN SOME CASES/. HOWEVER...LACK OF BLOCKING IN THE FAST QUASI-ZONAL FLOW WILL KEEP THE ARCTIC POOL OF BITTERLY COLD AIR TRUCKING ON EAST /AND MODIFYING/ VS. SOUTHEAST AND THUS OUR LOCAL AREA BECOMES MORE AND MORE REMOVED FROM THE COLDEST AIR W/TIME. THUS...TEMP GRADIENT WILL SLOWLY RELAX ALONG THE FRONT IN THE NEXT 12 HOURS. WILL STILL BE AN IMPRESSIVE FRONT AS IT COMES THROUGH TONIGHT...WITH UP TO A 20 DEGREE TEMP DROP OVER 3-4 HOURS AND A RATHER ABRUPT WIND SHIFT TO THE NORTHWEST /WITH GUSTS/. HAVE FOLLOWED RAW 2M MODEL TEMP BLEND CLOSELY TO MITIGATE MINOR SPEED DIFFERENCES OF FRONTAL PASSAGE. THIS PUTS FRONT TO SCIOTO COUNTY /OH/ BY 12Z MONDAY..WITH TEMPS AT SUNRISE ON MONDAY LIKELY RANGING FROM NEAR OR JUST BELOW FREEZING /CELINA OH/ TO THE LOW TO MID 50S /PORTSMOUTH/. HAVE USED A BLEND OF NCEP HI-RES WINDOW GUIDANCE /ARW AND NMM CORES/ WITH SUBJECTIVE INTERPOLATION OF 30.17Z ESRL HRRR FOR TIMING OF RAIN WITH FRONTAL PASSAGE TONIGHT. THESE DATA SUGGEST WE WILL CONTINUE TO SEE SCT AREAS OF RAIN DEVELOP IMMEDIATELY AHEAD OF THE COLD FRONT AND A FINE LINE OF LIGHT RAIN DEVELOP ALONG/IMMEDIATELY BEHIND THE FRONT AND SWEEP THROUGH THE AREA PARTICULARLY AFTER 00Z. RECENT RADAR TRENDS TO OUR NW SUPPORT THIS REASONING. ALREADY SEEING SW-NE ORIENTED BANDS OF -DZ ACRS WCNTL OH NOW IN FRONT OF PRIMARY FINE LINE ALONG FRONT. KEEPING A 60-75% OF MEASURABLE RAIN AT MOST LOCATIONS WITH THE FRONTAL PASSAGE TONIGHT. AM PROBABLY TO LONG /DURATION/ WITH THREAT OF RAIN GIVEN DEPICTIONS IN SIMULATED REFLECTIVITY BUT TRIED TO KEEP RAIN TO NO MORE THAN 2-3 HOURS AT ANY ONE LOCATION. FRONT WILL BEGIN TO SLOW OVER KY TOMORROW AS IT SAGS SOUTH OF STRONGER/FASTER WESTERLY FLOW...BECOMING MORE PARALLEL THE DEEP LAYER FLOW. THIS SHOULD SERVE TO LINGER RAIN IN NORTHERN KY/FAR SOUTHERN OHIO /APPROX SOUTH OF CINCINNATI TO CHILLICOTHE LINE/ INTO THE AFTERNOON. LITTLE CONCERNED WITH THE 30.12Z RUNS OF GFS/ECMWF WHICH ENHANCE POST FRONTAL PCPN BANDS LATE MORNING/AFTN ALONG AND SOUTH OF AFOREMENTIONED LINE. QPF SEEMS LIGHT...BUT BOTH MODELS SUGGESTING 0.10 TO 0.20" QPF DEVELOPING IN RESPONSE TO MID LEVEL FRONTOGENESIS /FGEN/ SIGNAL THAT ACCOMPANIES BRIEF WINDOW OF RIGHT ENTRANCE ULJ FORCING THAT HAS WEAK SHORTWAVE/VORTICITY EMBEDDED IN THIS ANTICYCLONIC PORTION OF THE UPPER JET. THIS CAUSES CONCERN BECAUSE OF MARGINAL/CRITICAL THERMAL STRUCTURE OF THE BOUNDARY LAYER BY THE TIME...AS CAA WILL BE STRONG AND TEMPS/DWPTS WILL HAVE FALLEN/OR BE FALLING TO NEAR FREEZING...ESP ALONG OHIO RIVER. CLOSER INSPECTION OF 30.12Z LAYER MAX WET BULB TEMPS SUGGESTS 30.12Z ECMWF IS VERY BULLISH/FAST WITH THE CAA WHILE 30.12Z NAM/SREF MEAN THE SLOWEST...WITH 30.12Z GFS A MIDDLE OF THE ROAD SOLUTION. UNFORTUNATELY 30.12Z ECMWF IS ALSO MOST ROBUST WITH ITS LIGHT QPF DISTRIBUTION IN THE WAKE OF THE FRONT WITH THE STRONGEST CONTRIBUTION FROM THE UPPER JET - SO THIS PRESENTS A LOWER-END THREAT OF A PERIOD OF SNOW /VIA WET BULB PROCESSES AND CAA/ FOR PORTIONS OF NORTHERN KY AND/OR SRN OHIO MONDAY BEFORE PRECIPITATION WANES. HAVE NOT REALLY SEEN THIS THREAT ON PRIOR PARALLEL GFS...OPNL NAM...OR HIGHER RES GEM/HIRES-WINDOW RUNS...THESE PUSH FRONT FURTHER SOUTH AND THUS POST FRONTAL PCPN BANDS DEVELOP FURTHER SOUTH AND IN WARMER AIR /RAIN/. ALSO...COARSE 30.12Z ECMWF FORECAST SOUNDINGS /NOT NATIVE MODEL RES/ SUGGESTS MID LEVEL DRY AIR MAY INHIBIT MUCH PRECIP PRODUCTION AND PERHAPS HIGHER QPF DEPICTION FURTHER NORTH INTO COLD AIR A FUNCTION OF COARSE GRID RESOLUTION. SO MAIN CHANGE TO FORECAST WAS TO 1) LINGER HIGHER END RAIN CHANCES IN THE SOUTH ON MONDAY LATE MORNING AND AFTERNOON AND 2) ALLOW FOR THIS TO MIX WITH SNOW AS A START WITHOUT ANY ACCUMULATION. UPCOMING SHIFTS WILL NEED TO MONITOR FOR WHAT APPEARS TO BE A LOWER END/OUTLIER THREAT FOR A STRIPE OF LIGHT/WET ACCUMULATIONS IN OUR SOUTH ON MONDAY AFTN SHOULD A MORE ROBUST COLDER/WETTER ECMWF SCENARIO GARNER MORE NWP SUPPORT. && .SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/... BATCH OF MID LEVEL FGEN FORCING/WEAK VORT MAX AND RIGHT ENTRANCE REGION OF UPPER JET SHIFTS EAST LATER MONDAY NIGHT AND THUS EXPECT A PERIOD OF DRY CONDITIONS FROM MONDAY EVENING INTO TUESDAY AS 1045MB ARCTIC HIGH PRESSURE MOVES ACROSS SERN CANADA AND OUR SOURCE REGION AIRMASS EMANATES FROM THIS FEATURE ON NELY FLOW. A CHILLY MONDAY NIGHT IN THE MID 20S TO AROUND 30 BEFORE BACKING LOW AND MID LEVEL FLOW ALREADY STARTS TO ALLOW MIXING/EROSION OF THE VERY SHALLOW ARCTIC AIRMASS BY TUESDAY. AM ALLOWING MAX TEMPS ON TUESDAY BACK NEAR 40F BUT WAA WILL BE ONGOING ESPECIALLY JUST OFF THE SURFACE SO THESE READINGS COULD BE A LITTLE COOL GIVEN 925MB TEMPS BY MID AFTERNOON WILL BE 0C TO +5C ALREADY IN THE STRENGTHENING WAA REGIME. RATHER DECENT S/W TROUGH DIGGING THROUGH MN/WI TUESDAY NIGHT /INDUCING THE BACKING FLOW OVER THE OHIO VALLEY/ WILL ALLOW REMNANT MOISTURE/ISENTROPIC ASCENT OVER THE SHALLOW COLD DOME TO PERHAPS PRODUCE SOME LIGHT RAIN/DRIZZLE ESPECIALLY IN THE AREAS EAST OF I-71 TUESDAY NIGHT. BOUNDARY LAYER TEMPS SHOULD RISE THROUGH THE NIGHT...SO HAVE KEPT ANY POTENTIAL OF LIGHT FREEZING RAIN OUT OF THE FORECAST FOR TUESDAY NIGHT. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... OUR REGION WILL REMAIN UNDER THE INFLUENCE OF A PROGRESSIVE ZONAL FLOW PATTERN THROUGH AT LEAST THE END OF THE WORK WEEK...ALLOWING FOR MOISTURE TO CONTINUE TO STREAM IN FROM THE WEST/SOUTHWEST. AS IS TYPICAL IN A MORE PROGRESSIVE FLOW PATTERN...THE MODELS ARE STRUGGLING WITH THEIR TIMING AND PLACEMENT OF SEVERAL EMBEDDED SHORTWAVES. AS A RESULT...IT IS TOUGH TO RULE OUT A CHANCE OF RAIN WEDNESDAY THROUGH FRIDAY. THE MODELS DO SEEM TO BE TRENDING TOWARD THE BETTER MOISTURE/FORCING AFFECTING MORE OF OUR SOUTHERN FA THOUGH...SO WILL TREND POPS ACCORDINGLY WITH THE LOWEST POPS NORTHWEST AND THE HIGHEST IN THE SOUTHEAST. DUE TO THE TIMING ISSUES THOUGH...WILL KEEP POPS IN CHANCE CATEGORY OR LOWER. THE LOW LEVELS SHOULD REMAIN WARM ENOUGH TO SUPPORT PRIMARILY RAIN...BUT DEPENDING ON THE EXACT TIMING AND PLACEMENT...SOME SNOW COULD MIX IN ACROSS THE NORTH THURSDAY NIGHT INTO FRIDAY. TEMPERATURES SHOULD REMAIN FAIRLY SEASONABLE THROUGH FRIDAY...WITH HIGHS GENERALLY IN THE 40S AND OVERNIGHT LOWS MOSTLY IN THE 30S. THE MID LEVEL FLOW PATTERN WILL BEGIN TO AMPLIFY THROUGH THE WEEKEND WITH SOME MID LEVEL RIDGING DEVELOPING ACROSS THE OHIO VALLEY REGION. THIS WILL ALLOW FOR SOME DRYING THROUGH THE WEEKEND ALONG WITH SLIGHTLY WARMER TEMPERATURES. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... ALL TAF SITES ARE NOW ON THE BACK SIDE OF THE SURFACE COLD FRONT. ADDITIONAL LIGHT PRECIPITATION WILL REMAIN POSSIBLE FOR SEVERAL HOURS BEHIND THE FRONT...AND FOR CINCINNATI...OCCASIONAL SHOWERS WILL LIKELY OCCUR THROUGH THE DAY ON MONDAY. AN AREA OF IFR CEILINGS (WITH MVFR VISIBILITIES) IS MOVING INTO THE REGION BEHIND THE FRONT. THESE CLOUDS WILL LIKELY BEGIN TO LIFT DURING THE MID-MORNING HOURS...AND VFR CONDITIONS ARE EXPECTED BY AFTERNOON. WINDS BEHIND THE FRONT ARE OUT OF THE NW...AND WILL SWITCH TO THE NORTH BY MONDAY AFTERNOON. A FEW GUSTS OF AROUND 20 KNOTS WILL BE POSSIBLE...MAINLY FROM LATE MORNING THROUGH MID-AFTERNOON. WINDS WILL CONTINUE A CLOCKWISE TURNING MONDAY NIGHT...WITH ENE FLOW EXPECTED AT THE END OF THE FORECAST PERIOD. OUTLOOK...MVFR CEILINGS ARE POSSIBLE TUESDAY INTO THURSDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...BINAU NEAR TERM...AR SHORT TERM...BINAU LONG TERM...JGL AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
248 AM CST MON DEC 1 2014 .DISCUSSION... HPX RADAR IMAGERY THIS MORNING CLEARLY DEPICTS COLD FRONT WHICH IS MOVING SOUTHEAST AROUND 15 KTS AND JUST ABOUT TO ENTER CLARKSVILLE. SURFACE OBS SHOW TEMPERATURES HAVE BEEN FALLING A CONSISTENT 15 DEGREES IN THE FIRST HOUR AFTER FROPA...THEN ANOTHER 5 DEGREES IN THE SECOND HOUR. THUS HIGH TEMPERATURES IN THE NORTHWEST HALF OF THE FORECAST AREA WILL BE REACHED EARLY THIS MORNING WITH TEMPS QUICKLY FALLING INTO THE 40S...WHILE SOUTHEAST HALF WILL BE ABLE TO WARM INTO THE 60S PRIOR TO FROPA LATER TODAY. CURRENT COLD FRONT SPEED OF FRONT HAS IT ARRIVING IN DOWNTOWN NASHVILLE AROUND 11Z...ALTHOUGH FRONT IS EXPECTED TO SLOW DOWN LATER THIS MORNING PER 00Z GUIDANCE AS UPPER SUPPORT LIFTS OFF TO THE NORTHEAST AND BOUNDARY BECOMES MORE PARALLEL TO THE ZONAL FLOW ALOFT. A FEW SHOWERS ALSO NOTED ALONG FRONT BUT MORE WIDESPREAD RAIN REMAINS OFF TO THE NORTHWEST...BUT HRRR SHOWS SHOWERS WILL INCREASE THROUGH THE DAY AS AN UPPER WAVE APPROACHES FROM THE WEST...WARRANTING LIKELY TO CATEGORICAL POPS AREAWIDE. MAIN FORECAST ISSUES THE REST OF THE WEEK WILL REVOLVE AROUND TEMPERATURES AS FRONT MEANDERS BACK AND FORTH ACROSS THE MID STATE...BUT A GENERALLY WET AND MILD PATTERN IS IN STORE WITH TEMPS RUNNING NEAR TO ABOVE NORMAL FOR THIS TIME OF YEAR. COLD FRONT EXPECTED TO GRIND TO A HALT TONIGHT JUST SOUTHEAST OF THE CWA...WITH SHOWERS GRADUALLY EXITING THE CWA TO THE EAST. FRONT LOOKS TO SLOWLY LIFT BACK NORTHWARD TUESDAY INTO WEDNESDAY AS ANOTHER UPPER TROUGH ENTERS THE GREAT LAKES WITH A SLIGHT WARMUP IN TEMPS...THEN MOVE BACK SOUTH ON THURSDAY AS TROUGH EJECTS TO THE EAST WITH ANOTHER BRIEF COOLDOWN. TEMPS AND POPS WERE KEPT NEAR THE SUPERBLEND OF ALL GUIDANCE AND CLOSE TO SURROUNDING OFFICES. UNUSUALLY WEAK SPLIT FLOW FOR THE BEGINNING OF WINTER DEVELOPS ALOFT BY THE WEEKEND WITH SUBTROPICAL JET BECOMING DOMINANT OVER OUR REGION...AND MODELS ARE REALLY STRUGGLING ON HOW TO HANDLE THIS CONVOLUTED UPPER PATTERN. NEVERTHELESS...BOTH 00Z GFS/ECMWF DEPICT A WEAK SHORTWAVE TROUGH MOVING ACROSS THE AREA FRIDAY AND SATURDAY...RESULTING IN FRONT LIFTING NORTHWARD ONCE AGAIN WITH WARMER TEMPS AND SCATTERED TO NUMEROUS SHOWERS. CANNOT EVEN RULE OUT SOME ISOLATED THUNDERSTORMS ESPECIALLY IF THE STRONGER 00Z ECMWF SOLUTION VERIFIES. FORECAST VERY UNCERTAIN AFTER SATURDAY AS EURO MODEL FINALLY SHOVES FRONT OUT OF THE REGION BUT GFS WANTS TO KEEP IT AROUND...SO KEPT LOW POPS IN THE GRIDS/ZONES ALONG WITH SEASONABLE TEMPS. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 54 40 50 46 / 80 60 30 30 CLARKSVILLE 44 36 46 41 / 80 60 20 20 CROSSVILLE 62 43 56 50 / 70 70 40 50 COLUMBIA 61 41 51 46 / 70 60 30 30 LAWRENCEBURG 64 40 52 47 / 60 60 30 30 WAVERLY 47 37 48 43 / 80 60 20 20 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHAMBURGER
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1140 PM CST SUN NOV 30 2014 .AVIATION... COLD AND DRY AIR CONTINUED TO MOVE SOUTHWARD INTO THE AREA BEHIND THE COLD FRONT THAT PASSED KPVW AND KLBB EARLIER IN THE EVENING... AND KCDS DURING THE AFTERNOON. SURFACE DEW-POINTS QUITE DRY AND WILL MAKE IT DIFFICULT FOR A SIGNIFICANT LOW CLOUD LAYER TO DEVELOP IN OUR AREA. THE SHORT RANGE HRRR SOLUTION HAS BEEN TRENDING DRIER ALL EVENING AT THE H850 MILLIBAR LEVEL...WITH THE WRF/NAM STICKING TO ITS GUNS ABOUT LOW CLOUDS DEVELOPING NEAR KCDS BY 06Z. SATELLITE DOES NO SHOW LOW CLOUD DEVELOPMENT YET SO WE ARE GIVING THE LEAN TO THE HRRR...AND HAVE REMOVED LOW CLOUD MENTION OVERNIGHT AT KCDS. WE ALREADY HAD REMOVED LOW CLOUDS FROM KLBB AND KPVW. OTHERWISE LOOK FOR GUSTY WINDS OVERNIGHT WITH SPEEDS TAPERING OFF MID TO LATE MONDAY MORNING AND EVEN MORE-SO BY LATE MONDAY. RMCQUEEN && .PREV DISCUSSION... /ISSUED 543 PM CST SUN NOV 30 2014/ AVIATION... COLD FRONT HAS SLOWED MOVING INTO THE DEEP WARM WESTERLY FLOW OVER THE TEXAS SOUTH PLAINS...WITH LATEST HRRR SHOWING PASSAGE AT KPVW BY 01Z AND KLBB SHORTLY AFTER 02Z. WE HAVE INCORPORATED THESE SLIGHT DELAYS INTO THE LATEST TAF OUTPUT. TRENDS ALSO SUPPORT LESS CONSIDERATION OF AN MVFR CLOUD LAYER FOR KPVW AND KLBB IN PARTICULAR...BUT ALSO LESS CONFIDENCE FOR KCDS AS WELL. THE LOW LEVEL AIRMASS IS PROVING SO DRY THAT EVEN THE SHARP FRONTAL LIFT MAY BE INSUFFICIENT TO DEVELOP MUCH IN THE WAY OF LOW CLOUDS. THE WRF/NAM HOWEVER REMAINS INSISTENT ON THIS LAYER FOR KCDS LATER TONIGHT THROUGH MONDAY MORNING AND THE LATEST HRRR AT LEAST TRIES TO SATURATE THIS LAYER NEAR OR JUST SOUTH OF KCDS BY 06Z-07Z. WE WILL MAINTAIN A BROKEN 2000 FOOT LAYER ONLY FOR KCDS FOR NOW AND REASSESS AS REALITY DEVELOPS. SURFACE GRADIENT WILL GRADUALLY SLACKEN TOMORROW AFTER 18Z...BUT WE DID NOT ADD ANOTHER CHANGE GROUP TO ACCOUNT FOR THIS YET. RMCQUEEN PREV DISCUSSION... /ISSUED 328 PM CST SUN NOV 30 2014/ SHORT TERM... WE ARE IN THE MIDST OF ANOTHER UNSEASONABLY WARM DAY AS 20Z TEMPERATURES ARE MOSTLY IN THE 70S...WITH EVEN A FEW LOWER 80S MIXING IN OFF THE CAPROCK. IN FACT...CHILDRESS HAS AGAIN BROKEN ITS RECORD HIGH FOR THE DATE REACHING 81 DEGREES...TWO DEGREES ABOVE THE PREVIOUS RECORD SET IN 1970. LUBBOCK HAS MADE IT TO 79 DEGREES SO FAR WHICH IS A COUPLE OF DEGREES SHY OF THE RECORD SET IN 2012. AS ADVERTISED FOR SOME TIME...THIS NEAR RECORD TO RECORD WARMTH WILL COME TO AN ABRUPT END THIS EVENING AS A STRONG COLD FRONT PLUNGES THROUGH. AS OF 20Z...THE COLD FRONT WAS ALREADY EDGING INTO THE NORTHEASTERN ZONES...STRETCHING FROM DALHART TO GOODNIGHT TO MEMPHIS TO NEAR ALTUS OKLAHOMA. THIS FRONT WAS ADVANCING STEADILY SOUTHWEST AND IT WILL ACCELERATE THROUGH THE LATE AFTERNOON AND EVENING HOURS...LIKELY PUSHING THROUGH LUBBOCK BETWEEN 01-03Z AND CLEARING THE FAR SOUTHWEST ZONES BY AROUND OR SHORTLY AFTER MIDNIGHT. GIVEN AFTERNOON TEMPERATURES BEHIND THE FRONT IN KANSAS ARE ONLY IN THE 20S...THERE WILL BE STOUT COLD AIR ADVECTION BEHIND THE FRONT. EXPECT GUSTY NORTHEASTERLY WINDS SUSTAINED AT 15 TO 25 MPH TO BE COMMON MUCH OF THE OVERNIGHT WITH MORNING LOWS BOTTOMING OUT IN THE TEENS NORTH TO LOWER TO MIDDLE 20S SOUTH. THESE TEMPERATURES... COUPLED WITH THE WINDS...WILL RESULT IN WIND CHILLS IN THE SINGLE DIGITS FOR MANY SPOTS TOMORROW MORNING MAKING FOR BRUTAL BUT APPROPRIATE START TO DECEMBER. THERE REMAINS SOME UNCERTAINTY WHETHER OR NOT A SHALLOW LAYER OF STRATUS WILL FORM WELL BEHIND THE FROPA LATE TONIGHT GIVEN STRONG COOLING ACTING ON A RELATIVELY DRY AIRMASS. WE WOULD EXPECT AT LEAST SOME STRATUS TO ROAM THE AREA MONDAY MORNING...LIKELY FAVORING SPOTS OFF THE CAPROCK WHERE THERE WILL BE A LITTLE MORE MOISTURE TO WORK WITH...THOUGH ALMOST ANYWHERE COULD SEE A SHORT BOUT OF STRATUS. WHATEVER LOW CLOUDS FORM SHOULD GRADUALLY DIMINISH BY MIDDAY OR EARLY AFTERNOON MONDAY...THOUGH A WEAK SHORTWAVE GLIDING BY TO THE NORTH IN NEAR ZONAL FLOW ALOFT WILL INCREASE HIGH CLOUDS DURING THE AFTERNOON HOURS. NO RECORD HIGHS WILL BE BROKEN TOMORROW WITH TEMPERATURES ONLY EXPECTED TO PEAK IN THE 30S FOR MOST SPOTS. THE BREEZY NORTH WINDS IN THE MORNING WILL GRADUALLY DIMINISH THROUGH THE AFTERNOON AS THE PRESSURE GRADIENT RELAXES. LONG TERM... ONLY MINOR CHANGES MADE TO THIS LONG TERM FORECAST...AS THE FOCUS NOW SHIFTS TO INCREASING PRECIPITATION CHANCES TOWARDS THE WEEKEND. WHILE SOME MODEL SOLUTIONS CONTINUE TO INDICATE THAT LIGHT RAIN COULD BEGIN AS EARLY AS LATE THURSDAY...ALL INDICATIONS ARE THAT BEST CHANCES WILL OCCUR LATE SATURDAY THROUGH SUNDAY. TO BEGIN THE PERIOD EARLY TUESDAY...TEMPERATURES SHOULD QUICKLY RECOVER INTO THE 50S AND LOW 60S FOLLOWING MONDAYS COLD FRONT...AS PRESSURE FALLS ACROSS THE HIGH PLAINS WILL FORCE THE QUICK RETURN OF SOUTHWEST WINDS. THIS WILL ALSO DRAW INCREASING MOISTURE NORTHWARD THROUGH THE DAY AND OVERNIGHT...AND MODEL GUIDANCE SUGGESTS THAT THIS MAY BE ENOUGH TO RESULT IN SOME PATCHY FOG ACROSS THE SOUTHERN SOUTH AND ROLLING PLAINS BY EARLY WEDNESDAY MORNING. FARTHER NORTH...MORE LIMITED MOISTURE AND THE PRESENCE OF A SUBSTANTIAL MID TO HIGH LEVEL CLOUD LAYER WILL LIKELY PROVE TO PROHIBITIVE FOR FOG DEVELOPMENT...AND MAY EVEN LIMIT IT TO AREAS ACROSS THE PERMIAN BASIN. STILL...ENOUGH CONFIDENCE EXISTS FOR SOME LOW-END MENTION AT THIS TIME ACROSS THE AREAS PREVIOUSLY MENTIONED. DURING THE DAY WEDNESDAY...YET ANOTHER SUBTLE AND PROGRESSIVE SHORTWAVE WILL MOTOR ACROSS THE AREA...SENDING YET ANOTHER COLD FRONT THROUGH THE REGION. ACROSS THE BOARD...LATEST GUIDANCE HAS TRENDED A BIT STRONGER WITH THIS FRONT THAN IN PREVIOUS SOLUTIONS...SO WE OPTED TO COOL WEDNESDAYS HIGHS A FEW MORE DEGREES...PARTICULARLY ACROSS THE NORTHERN SOUTH AND ROLLING PLAINS. IN ANY CASE...THIS WAVE APPEARS TO BE ANOTHER DRY ONE. ALL EYES THEN TURN TO THE NEXT WAVE...WHICH CONTINUES TO BE HANDLED WITH POOR AGREEMENT AMONGST MODELS DESPITE GENERAL OVERALL IMPROVEMENT THROUGH THE REST OF THE LONG TERM PERIOD. ON ONE HAND...THE GFS CONTINUES TO INDICATE A MORE POTENT SHORTWAVE WITH MORE RAPID MOISTURE RETURN...AND LIKEWISE DEVELOPS LIGHT QPF ACROSS PRIMARILY THE SOUTHERN SOUTH PLAINS AND ROLLING PLAINS AS EARLY AS LATE THURSDAY. OVERALL...IT DOES APPEAR THAT DESPITE ITS STUBBORNNESS WITH THIS PARTICULAR FEATURE...THE GFS SEEMS TO BE DRIFTING CLOSER TO THE ECMWF IN ITS DEPICTION OF THE REMAINDER OF THE LONG TERM PERIOD. THUS...WE WILL CONTINUE TO MAINTAIN A DRY FORECAST THROUGH AT LEAST EARLY SATURDAY WHEN A MUCH MORE SUBSTANTIAL WAVE IS EXPECTED TO IMPACT THE AREA. WHILE SLIGHT TIMING DIFFERENCES PERSIST...THE WINDOW FOR SUBSTANTIAL PRECIPITATION SEEMS TO BE NARROWING TO A LATE SATURDAY THROUGH SUNDAY TIME FRAME. AT 6-7 DAYS AWAY...MANY DETAILS REMAIN UNCLEAR...BUT SLOWLY IMPROVING AGREEMENT AMONG SOLUTIONS IS PROMISING. FIRE WEATHER... NEAR RECORD TEMPERATURES...HUMIDITIES OF 7 TO 13 PERCENT AND WESTERLY WINDS SUSTAINED AT 15 TO 25 MPH WERE CREATED ELEVATED TO BRIEFLY CRITICAL FIRE WEATHER ACROSS MOST OF THE CAPROCK THIS AFTERNOON. CONDITIONS WILL QUICKLY IMPROVE BY EARLY EVENING AS WINDS DIMINISH...BUT A COLD FRONT WILL PLUNGE FROM NORTHEAST TO SOUTHWEST ACROSS THE SOUTH PLAINS THROUGH THE EVENING HOURS BRINGING AN ABRUPT NORTHEASTERLY WIND SHIFT THAT COULD COMPLICATE ANY ONGOING FIRE FIGHTING OPERATIONS. GUSTY NORTHEASTERLY WINDS...DRASTICALLY COLDER TEMPERATURES AND IMPROVING HUMIDITIES WILL FOLLOW THE COLD FRONT WITH HIGHS ON MONDAY AFTERNOON ABOUT 40-50 DEGREES COLDER THAN TODAY. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 16 35 17 64 38 / 0 0 0 0 0 TULIA 16 34 19 60 39 / 0 0 0 0 0 PLAINVIEW 17 36 21 59 40 / 0 0 0 0 0 LEVELLAND 20 39 22 61 39 / 0 0 0 0 0 LUBBOCK 19 38 23 60 40 / 0 0 0 0 0 DENVER CITY 24 40 26 58 40 / 0 0 0 0 0 BROWNFIELD 23 39 25 59 40 / 0 0 0 0 0 CHILDRESS 22 36 22 58 41 / 0 0 0 0 0 SPUR 21 37 23 59 40 / 0 0 0 0 0 ASPERMONT 24 37 26 59 43 / 0 0 0 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99/05
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
206 AM CST MON DEC 1 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 206 AM CST MON DEC 1 2014 CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED TROUGHS ALONG THE BRITISH COLUMBIA COAST AND FROM NORTHERN ONTARIO INTO CENTRAL MN....WITH WEAK RIDGING IN-BETWEEN OVER MONTANA AND ALBERTA. SOME PACIFIC MOISTURE WAS STREAMING INTO SOUTHERN PORTIONS OF THE FORECAST AREA AHEAD OF THE CENTRAL MN TROUGH... MANIFESTING ITSELF AS HIGH CLOUDS. CLEAR SKIES DOMINATE THE REST OF THE FORECAST AREA INTO THE NORTHERN PLAINS...RESULTING FROM A DRY ARCTIC AIRMASS IN PLACE. PRECIPITABLE WATER VALUES OF 0.10 INCHES OR LESS...20 TO 40 PERCENT OF NORMAL...WERE OBSERVED ON 00Z SOUNDINGS. MEANWHILE...925MB TEMPS WERE IN THE -15 TO -18C RANGE. THE COMBINATION OF THE CLEAR SKIES...DRY AIR...NIGHT TIME COOLING AND SOME SNOWPACK HAS ALLOWED READINGS TO DIP INTO THE SINGLE DIGITS BELOW ZERO ACROSS PORTIONS OF SOUTHEAST MN AND NORTH CENTRAL WI...AND SINGLE DIGITS ABOVE ZERO TO MID TEENS ELSEWHERE. A PERSISTENT 5 TO 15 MPH BREEZE HAS RESULTED IN WIND CHILLS OF ZERO TO 15 BELOW ZERO. THE SURFACE HIGH ASSOCIATED WITH THE ARCTIC AIR WAS STILL SITUATED OVER THE DAKOTAS. VERY CHILLY CONDITIONS START OFF THE FIRST DAY OF DECEMBER. ALTHOUGH PLENTY OF SUNSHINE IS EXPECTED AS THE SURFACE HIGH OVER THE DAKOTAS EVENTUALLY MOVES OVERHEAD BY SUNSET...925MB TEMPS IN THE -16C SOUTH TO -20C NORTH AT 18Z WILL LIMIT TEMPERATURES FROM CLIMBING TOO MUCH. 2 METER MODEL OUTPUT AND VARIOUS MOS GUIDANCE ARE ALL IN VERY GOOD AGREEMENT FOR TODAYS HIGHS...WITH READINGS MAINLY BETWEEN 5 AND 15 ABOVE. SHOULD THESE COME TO PASS...WE ARE LOOKING AT ONE OF THE TOP 5 COLDEST HIGHS FOR DECEMBER 1ST. WIND CHILLS WILL REMAIN AN ISSUE TO CONTEND WITH THIS MORNING AS THE 5 TO 15 MPH BREEZE PERSISTS. EXPECT DIMINISHING WINDS IN THE AFTERNOON COMBINED WITH CLIMBING TEMPERATURES TO HELP IMPROVE WIND CHILLS. CLEAR SKIES...VERY DRY AIR AND LIGHT WINDS EARLY THIS EVENING WITH THE SURFACE HIGH IN PLACE SHOULD PROMOTE A RAPID TEMPERATURE DROP AFTER SUNSET. SOME LOCATIONS COULD SEE A DROP OF 10 TO 15 DEGREES BETWEEN 21-00Z. MODELS ARE IN GOOD AGREEMENT PUSHING THE HIGH QUICKLY OFF TO THE EAST DURING THE NIGHT...MOVING INTO EASTERN WI BY 06Z AND LOWER MI BY 12Z. THIS ALLOWS THE GRADIENT TO TIGHTEN UP AND THUS AN INCREASE OF SOUTHERLY WINDS TO BRING WARMER AIR BACK INTO THE REGION. THE PROBLEM WE COULD RUN INTO IS WIND CHILLS BACK DOWN TO ADVISORY CRITERIA OF -20...DUE TO THE ONSET OF THE WINDS WITH THE COLD TEMPERATURES IN THE EVENING. THUS...ANOTHER WIND CHILL ADVISORY MAY BE NEEDED FOR SOME AREAS AFTER THE CURRENT ONE ENDS. TAYLOR COUNTY APPEARS TO BE THE BEST CANDIDATE FOR AN ADVISORY WITH SOME OF SOUTHEAST MN PERHAPS NEEDING INCLUSION AS WELL. AN INCREASING MID CLOUD DECK TOWARDS 12Z ACCOMPANYING THE WARM ADVECTION SHOULD ALSO HELP TO GIVE TEMPERATURES A BOOST. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 206 AM CST MON DEC 1 2014 FOCUS/ATTENTION FOR THE TUESDAY THROUGH WEDNESDAY TIME PERIOD REMAINS ON THE CURRENT UPPER TROUGH ALONG THE BRITISH COLUMBIA COAST. MODEL AGREEMENT REMAINS GOOD BRINGING THIS TROUGH ACROSS THE NORTHERN PLAINS TUESDAY...ITS AXIS OVER THE FORECAST AREA BY 12Z WEDNESDAY...AND OFF INTO THE EASTERN GREAT LAKES BY 00Z THU. AHEAD OF THE TROUGH FOR TUESDAY...A BRISK SOUTHWEST WIND WILL HELP TO BOOST 925MB TEMPS UP TO -5 TO -8C BY 00Z. THESE READINGS COMBINED WITH SOME SUN FILTERED THROUGH PERIODS OF MID/HIGH CLOUDS SUPPORT HIGHS IN THE 20S TO LOW 30S...WARMEST IN FAR SOUTHWEST WI AND RIVER VALLEYS WHERE SNOW COVER IS LIMITED. AS WE HEAD INTO THE LATE AFTERNOON AND EVENING HOURS...MODEL DISAGREEMENT BEGINS TO SHOW UP NORTH OF I-90 IN THE PRECIPITATION DEPARTMENT. THE 01.00Z NAM AND REGIONAL CANADIAN MODELS WANT TO PRODUCE SOME LIGHT SNOW... ESPECIALLY NORTH OF I-94. THE 01.00Z GFS AND FOR THE MOST PART THE 01.00Z ECMWF ARE DRY. BOTH MODEL GROUPS DEPICT WEAK ISENTROPIC LIFTING IN THE 900-600MB LAYER...BUT THE DIFFERENCE IS THAT THE NAM/REGIONAL CANADIAN HAVE MORE MOISTURE IN THE 900-700MB LAYER. HARD TO SAY AT THIS POINT WHAT THAT LAYER MOISTURE WILL LOOK LIKE SO MAINTAINED SOME LOW CHANCES OF PRECIPITATION NORTH OF I-94 FOR THE LATE AFTERNOON/EVENING HOURS. ANY SNOW SHOULD PUSH OFF TO THE EAST AFTER 06Z AS THE UPPER TROUGH AXIS MOVES IN AND A COLD FRONT PASSES THROUGH. THIS COLD FRONT WILL USHER IN SLIGHTLY COOLER AIR FOR WEDNESDAY AS 925MB TEMPS FALL TO -6 TO -10C. THERE SHOULD BE PLENTY OF SUN ON WEDNESDAY AS DRY AIR AND SUBSIDENCE MOVES IN BEHIND THE UPPER TROUGH...SO HIGHS ARE EXPECTED TO BE NEAR OR JUST A LITTLE COOLER THAN TUESDAY. FROM WEDNESDAY NIGHT THROUGH FRIDAY...THE UPPER FLOW IS PROGGED TO BECOME MORE ZONAL...WITH NORTHERN AND SOUTHERN STREAMS BECOMING MORE EVIDENT. THE NORTHERN STREAM LOOKS TO TRACK ACROSS SOUTHERN CANADA WHILE THE SOUTHERN STREAM BECOMES POSITIONED ACROSS THE SOUTHERN U.S.. THE IMPACT TO THE FORECAST AREA FROM THE POSITIONS OF THESE STREAMS IS A WARMING TREND AS PACIFIC AIR FLOWS EASTWARD...AS WELL AS DRY CONDITIONS WITH THE SOUTHERN STREAMING BLOCKING GULF MOISTURE. THERE IS ONE SMALL OPPORTUNITY DURING THIS PERIOD TO PICK UP SOME LIGHT SNOW AND THAT IS ON THURSDAY FROM THE 30.00Z/12Z AND 01.00Z ECMWF. THE ECMWF SUGGESTS A DECENT SHORTWAVE AS WELL AS BAND OF MID LEVEL FRONTOGENESIS AND MOISTURE TO HELP PRODUCE THE SNOW. HOWEVER...ALL OTHER GUIDANCE IS DRY...SUGGESTING THE DRY AIR THAT CAME IN ON WEDNESDAY WILL BE ENOUGH TO ABSORB ANY SNOW FALLING OUT OF THE MID CLOUD. CONSIDERED LEAVING THURSDAY DRY...BUT THE ECMWF CONTINUITY IS CONCERNING. THEREFORE...HAVE ADDED A 20 PERCENT CHANCE TO LOCATIONS NORTH OF I-90. THURSDAYS HIGHS MAY NOT BE MUCH DIFFERENT THAN WEDNESDAY DUE TO CLOUDS MOVING IN AND WARM ADVECTION JUST BEGINNING TO GET IN EARNEST. BETTER SHOT FOR WARMER CONDITIONS COMES FRIDAY AS 925MB TEMPS REACH -2 TO -4C. THOSE READINGS COULD SUPPORT 30S TO LOW 40S...BUT IT APPEARS WE WILL BE BATTLING LOW STRATUS PER ECMWF/GFS 925MB RH FIELDS NEAR SATURATION...THUS HAVE TEMPERED HIGHS SOME. HEADING INTO THE WEEKEND...THE SPLIT FLOW REGIME CONTINUES...WITH HIGH PRESSURE PROGGED AT THE SURFACE. THUS...WE SHOULD SEE A CONTINUATION OF DRY CONDITIONS. SOME DISCREPANCIES EXIST ON HOW WARM THE WEEKEND WILL BE...AND IN PARTICULAR SATURDAY WHERE THE ECMWF DRIVES A LITTLE BIT MORE COLD AIR INTO THE REGION COMPARED TO THE GFS. NEVERTHELESS...READINGS SHOULD BE CLOSE TO NORMAL ON SATURDAY WITH MORE CONFIDENCE OF ABOVE NORMAL ON SUNDAY AS 925MB TEMPS THEN CLIMB TO AT LEAST 0C...IF NOT SLIGHTLY HIGHER. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1108 PM CST SUN NOV 30 2014 VFR CONDITIONS TO CONTINUE INTO MONDAY EVENING. HIGH PRESSURE OVER THE WESTERN DAKOTAS WILL MOVE EAST ACROSS THE AREA AND INTO LOWER MICHIGAN BY MONDAY EVENING. OTHER THAN THE HIGH CLOUDS TONIGHT...SKIES ARE EXPECTED TO BE CLEAR FOR MONDAY. THE NORTHWEST WINDS WILL DROP BELOW 10 KNOTS MONDAY MORNING AND THEN SWING AROUND TO THE SOUTHEAST MONDAY EVENING ON THE BACK SIDE OF THE HIGH. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR WIZ017-029- 032>034-042. MN...WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR MNZ079-086- 087-094-095. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...04
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1135 PM CST SUN NOV 30 2014 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .SHORT TERM...TONIGHT AND MONDAY ISSUED AT 252 PM CST SUN NOV 30 2014 THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A POLAR FRONT MOVING ACROSS MICHIGAN EARLY THIS AFTERNOON. EARLIER TEMPERATURES IN THE MIDDLE 30S OVER EASTERN WISCONSIN HAVE FALLEN INTO THE UPPER 20S OVER MUCH OF THE FOX VALLEY. LIGHT LAKE EFFECT SNOW SHOWERS CONTINUE TO PASS OVER N-C WISCONSIN WHERE TEMPS HAVE HOVERED ALL DAY IN THE TEENS. LOOKING UPSTREAM...MOSTLY CLEAR CONDITIONS RESIDE UPSTREAM OVER THE NORTHERN PLAINS THANKS TO A STRONG HIGH PRESSURE SYSTEM BUILDING INTO THAT PART OF THE COUNTRY. A REINFORCING ARCTIC FRONT IS DROPPING SOUTHEAST OVER THE LAKE WINNIPEG REGION...AND IS POISED TO MOVE THROUGH THE REGION TONIGHT. WITH THE PASSAGE OF THIS ARCTIC FRONT...WIND CHILL HEADLINES ARE THE MAIN FORECAST CONCERN. TONIGHT...A STRONG SHORTWAVE WILL MOVE ACROSS ONTARIO AND WILL DRIVE AN ARCTIC FRONT ACROSS THE STATE AFTER MIDNIGHT. AHEAD OF THE FRONT...MODELS PROJECT MID-LEVEL MOISTURE PULLING OUT TO THE NORTHEAST AND LOW LEVEL MOISTURE EXITING WITH THE POLAR FRONT. LAKE CLOUDS SHOULD ALSO BE RETREATING TO THE UPPER PENINSULA AS WINDS BACK MORE WESTERLY. THIS SHOULD LEAD TO MOSTLY CLEAR CONDITIONS FOR MUCH OF THE NIGHT. MODELS INDICATE THAT STRATO-CU COULD MOVE INTO NORTHERN WISCONSIN BEHIND THE ARCTIC FRONT AFTER MIDNIGHT...BUT THIS LOOKS OVERDONE BASED ON CLOUDS UPSTREAM. 925MB TEMPS WILL FALL INTO THE -20S BEHIND THE ARCTIC FRONT BY 12Z MONDAY AND UPSTREAM OBS OVER THE EASTERN DAKOTAS SUGGEST LOW TEMPS WILL FALL INTO THE MIDDLE SINGLE DIGITS BELOW ZERO OVER THE NORTH. THIS MATCHES FAIRLY WELL WITH THE AVERAGE BIAS CORRECTED GUIDANCE...AND THE PREVIOUS FORECAST. COMBINED WITH A BRISK NORTHWEST WIND...WIND CHILLS WILL FALL BETWEEN 20 AND 25 BELOW OVER N-C WISCONSIN. AS A RESULT...WILL HOIST A WIND CHILL ADVISORY STARTING LATE TONIGHT. MONDAY...COLD ADVECTION WILL CONTINUE MONDAY MORNING...AND COULD SEE TEMPERATURES CONTINUE TO FALL OVER EASTERN WISCONSIN THROUGH MID-MORNING. ARCTIC HIGH PRESSURE WILL THEN BUILD IN FOR THE AFTERNOON...AND SHOULD SEE THE GUSTY NORTHWEST WINDS SUBSIDE. THOUGH TEMPS ALOFT WILL BE MODIFYING...HIGHS WILL ONLY RANGE FROM THE SINGLE DIGITS ABOVE ZERO TO THE LOWER TEENS UNDER PLENTY OF SUNSHINE. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 252 PM CST SUN NOV 30 2014 UNLIKE NOVEMBER...DECEMBER LOOKS LIKE IT WILL BE RATHER MILD AT LEAST FOR THE FIRST WEEK OR SO. THE UPPER FLOW IS MOSTLY ZONAL WITH SURFACE HIGHS COMING FROM THE ROCKIES INSTEAD OF THE ARCTIC. TEMPERATURES ALOFT ARE GENERALLY TOO WARM FOR SIGNIFICANT LAKE EFFECT AND THERE ARE NO SIGNIFICANT SURFACE LOWS FORECAST TO IMPACT THE NORTHERN GREAT LAKES. THERE COULD BE SOME LAKE EFFECT SNOW FLURRIES OVER DOOR COUNTY LATE MONDAY NIGHT OR EARLY TUESDAY WAS SOUTHERLY FLOW MIGHT BE JUST COLD ENOUGH TO GET SOME SNOW SHOWERS. A WEAK COLD FRONT MOVING THROUGH TUESDAY EVENING MIGHT PRODUCE SOME SNOW SHOWERS BUT IT DOESN/T LOOK TO BE VERY MUCH. IT WILL START OUT ABOUT 5 DEGREES BELOW NORMAL TUESDAY AND WEDNESDAY BUT THEN TEMPERATURES WILL BE 5 TO 8 DEGREES ABOVE NORMAL AFTER THAT. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1126 PM CST SUN NOV 30 2014 A SECONDARY COLD FRONT WILL BRING SOME FLURRIES AND PATCHY MVFR CIGS TO NORTH CENTRAL WI LATE TONIGHT INTO MONDAY MORNING. LAKE EFFECT SNOW SHOWERS WILL ALSO BE POSSIBLE OVER VILAS COUNTY. THE FRONT WILL CAUSE BRISK NORTHWEST WINDS TO DEVELOP...WITH GUSTS TO 25 KTS POSSIBLE AT MOST LOCATIONS. THE WINDS WILL QUICKLY DECREASE AS ARCTIC HIGH PRESSURE ARRIVES MONDAY AFTERNOON. DEVELOPING SE WINDS MAY BRING SOME LAKE-EFFECT CLOUDS AND FLURRIES INTO THE LAKESHORE COUNTIES BY LATE MONDAY EVENING...BUT WILL JUST MENTION SCT LOW CLOUDS AT THE MTW TAF SITE FOR NOW. && .GRB WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY FROM 3 AM TO 10 AM CST MONDAY FOR WIZ005- 010>012-018-019-030. && $$ SHORT TERM.....MPC LONG TERM......RDM AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1007 AM EST MON DEC 1 2014 .SYNOPSIS... A COLD FRONT WILL MOVE ACROSS THE REGION THIS AFTERNOON FOLLOWED BY HIGH PRESSURE. A WAVE OF LOW PRESSURE OFF THE CAROLINA COAST MOVES TOWARD THE AREA TUESDAY AFTERNOON PUSHING A WARM FRONT TOWARDS THE AREA TUESDAY NIGHT. THE WARM FRONT PASSES TO THE NORTH ON WEDNESDAY...FOLLOWED BY A COLD FRONTAL PASSAGE WEDNESDAY EVENING. STRONG HIGH PRESSURE THEN BUILDS IN FOR THURSDAY. A PROLONGED PERIOD OF UNSETTLED WEATHER IS POSSIBLE FROM FRIDAY THROUGH NEXT WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... CHANGES THIS MORNING INCLUDE RAISING TEMPS FOR EASTERN PORTIONS AND INCREASING POPS FOR THIS EVENING. TEMPS ARE INTO THE LOWER 60S ON PARTS OF LONG ISLAND AS OF 10 AM. HAVE UPDATED TEMP FCST TODAY BASED ON LATEST TRENDS AND LAMP GUIDANCE. BIGGER CHANGE WAS TO INCREASE POPS FOR LIGHT RAIN MOVING IN THIS EVENING POST FRONTAL. HRRR, NARRE-TL AND RAP ALL SUGGESTING LIGHT RA IS LIKELY FOR THE EVENING. START TIME IS ABOUT 5 PM IN NYC AND THEN SPREADS ACROSS LONG ISLAND. LIFT COMES FROM JET DYNAMICS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... RAIN ENDS BEFORE MIDNIGHT OVER LONG ISLAND. UPPER FLOW BECOMES MORE ZONAL TONIGHT INTO TUESDAY...THEN A SHORTWAVE MOVES THROUGH THE NORTHERN STREAM FLOW TUESDAY AFTERNOON. AT THE SURFACE HIGH PRESSURE MOVES THROUGH THE GREAT LAKES AND NEW ENGLAND TONIGHT THROUGH TUESDAY. AGAIN GUIDANCE IS SIMILAR WITH THE HIGH. WITH THE HIGH TO THE NORTH A STRONG NORTHEAST TO EAST FLOW DEVELOPS AND COLD AIR DAMMING OCCURS. TUESDAY AFTERNOON A WAVE OF LOW PRESSURE DEVELOPS OFF THE CAROLINA COAST ON THE OLD FRONTAL BOUNDARY AS A SOUTHERN STREAM SHORTWAVE REACHES THE SOUTHEAST. THE LOW THEN MOVES NORTH ALONG THE COAST INTO THE COLD AIR. WITH THE STRONG HIGH TO THE NORTH THE GFS ERODES THE COLD AIR TOO QUICKLY...WHILE THE NAM AND ECMWF HOLD ON TO THE COLD AIR. LEANED TOWARD THE COLDER SOLUTIONS FOR PRECIPITATION TYPE WITH CHANCE POPS BY LATE TUESDAY. FOR TEMPERATURES ALSO LEANED TOWARD THE COOLER NAM AND ECS GUIDANCE FOR LOWS TONIGHT AND HIGHS TUESDAY. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... A WARM FRONT AND ACCOMPANYING WEAK SFC WAVE LIFTING NE ALONG THE COAST WILL BRING STEADY PCPN TO THE AREA TUE NIGHT. PCPN SHOULD BEGIN AS SNOW INLAND...THEN QUICKLY TRANSITION OVER TO MIXED PCPN AND THEN RAIN IN MOST PLACES BY LATE TUE EVENING AS TEMPS WARM ALOFT. THE EXCEPTION WILL BE WELL INLAND IN PLACES SUCH AS ORANGE... W PASSAIC...PUTNAM AND N FAIRFIELD COUNTIES...WHERE COLD AIR DAMMING IN THE WAKE OF A DEPARTING 1045 MB WILL LOCK IN SUB- FREEZING AIR... WITH SNOW TRANSITIONING TO LIGHT FREEZING RAIN. THE PCPN EVENT SHOULD BE LIGHT...SO ATTM DO NOT EXPECT MUCH MORE THAN AN UP TO AN INCH OF LIGHT SNOW INLAND...AND A LIGHT GLAZE OF ICE IN THE AREAS WHERE FREEZING RAIN DOES OCCUR. AS THE WARM FRONT LIFTS N WED MORNING...PCPN SHOULD QUICKLY TRANSITION TO LIGHT RAIN OR DRIZZLE...AND SW FLOW SHOULD BRING IN MILER AIR...WITH HIGHS IN THE LOWER/MID 50S THROUGHOUT PER WARMEST MOS GUIDANCE...A FEW DEG ABOVE NORMAL. A COLD FRONT SHOULD QUICKLY FOLLOW LATE WED AFTERNOON OR WED EVENING...WITH LOW TEMPS IN THE 30S WED NIGHT. AS AN UPPER TROUGH SWINGS E ACROSS NEW ENGLAND AN ERN CANADA...INCREASING SFC CONFLUENCE IN ITS WAKE WILL LEAD TO DEVELOPMENT OF STRONG HIGH PRESSURE OVER THE NRN PLAINS WED NIGHT THAT BUILDS E-WARD TOWARD THE AREA THU-FRI...WITH BELOW NORMAL TEMPS. AS THIS SECOND STRONG HIGH DEPARTS...WILL SEE A SCENARIO SIMILAR TO THAT OF TUE NIGHT UNFOLD FOR FRI NIGHT-SAT AS ANOTHER FRONTAL SYSTEM APPROACHES FROM THE SW...WITH WARMING ALOFT AND SFC COLD AIR DAMMING LEADING TO MIXED PCPN INLAND AND MAINLY RAIN AT THE COAST. SHOULD THEN SEE AN EXTENDED PD OF UNSETTLED WX...MAINLY RAIN AS A SLOW MOVING UPPER TROUGH APPROACHES FROM THE WEST. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... NO SIGNIFICANT CHANGES MADE TO THE PREVIOUS TAF PACKAGE. A COLD FRONT WILL MOVE ACROSS THE TERMINALS THIS AFTERNOON. MAINLY VFR. THERE IS A LOW POTENTIAL FOR MVFR CIGS WITH A FEW SHOWERS ACROSS COASTAL TERMINALS IN THE AFTERNOON INTO EARLY EVE AS THE FRONT MOVES THROUGH AND LINGERING IN ITS WAKE. CONFIDENCE IS TOO LOW TO INCLUDE IN THE TAFS. SOUTHWEST WIND OF AROUND 10 KT AHEAD OF THE COLD FRONT AND GUSTY NW WINDS IN WAKE OF THE COLD FRONT LATE THIS AFTERNOON INTO THE EVENING. DIMINISHING THREAT FOR MVFR CONDITIONS AND SHOWERS AS EVENING PROGRESSES. ...NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: CHANCE OF MVFR CIGS THIS AFTERNOON. TIMING OF WINDS COULD BE OFF BY AN HOUR OR TWO BASED ON TIMING OF THE COLD FRONTAL PASSAGE. KLGA FCSTER COMMENTS: TIMING OF WINDS COULD BE OFF BY AN HOUR OR TWO BASED ON TIMING OF THE COLD FRONTAL PASSAGE. KEWR FCSTER COMMENTS: TIMING OF WINDS COULD BE OFF BY AN HOUR OR TWO BASED ON TIMING OF THE COLD FRONTAL PASSAGE. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS YELLOW...WHICH IMPLIES SLANT RANGE VISIBILITY 4-6SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: TIMING OF WINDS COULD BE OFF BY AN HOUR OR TWO BASED ON TIMING OF THE COLD FRONTAL PASSAGE. KHPN FCSTER COMMENTS: TIMING OF WINDS COULD BE OFF BY AN HOUR OR TWO BASED ON TIMING OF THE COLD FRONTAL PASSAGE. KISP FCSTER COMMENTS: CHANCE OF MVFR CIGS THIS AFTERNOON. TIMING OF WINDS COULD BE OFF BY AN HOUR OR TWO BASED ON TIMING OF THE COLD FRONTAL PASSAGE. .OUTLOOK FOR 15Z TUE THROUGH FRI... .TUE...VFR INTO MID AFTERNOON...THEN A CHANCE OF MVFR CONDITIONS WITH LIGHT RAIN AND LIGHT SNOW. .TUE NIGHT...SN TO RA WITH MVFR OR LOWER CONDITIONS LIKELY. SN TO FZRA AT KSWF. .WED...CHANCE OF RAIN WITH MVFR OR LOWER CONDITIONS. LOW PROB OF FZRA AT KSWF IN THE MORNING. .THU...VFR .FRI...CHANCE OF LIGHT RAIN AND/OR SNOW IN THE AFTERNOON. && .MARINE... NO CHANGES AT THIS TIME...THOUGH WE MAY NEED SCA ALL WATERS THIS EVENING BEHIND THE COLD FRONT WITH COLD ADVECTION. SEAS ON THE OCEAN WATERS REMAIN AT SMALL CRAFT LEVELS THIS MORNING IN A SOUTHWEST FLOW AHEAD OF AN APPROACHING COLD FRONT. THEN WITH A WIND SHIFT TO THE NORTHWEST BEHIND THE FRONT...LATE THIS AFTERNOON INTO THIS EVENING...AND COLD ADVECTION WIND GUSTS ON THE OCEAN WATERS WILL BE AT MARGINAL SMALL CRAFT LEVELS. IN ADDITION SEAS WILL STILL BE AT SMALL CRAFT LEVELS AND SLOWLY SUBSIDING. SEAS MAY FALL BELOW SMALL CRAFT LATE TONIGHT INTO EARLY TUESDAY. HOWEVER...WITH A STRONG AND GUSTY NORTHEAST TO EAST FLOW DEVELOPING TUESDAY AS HIGH PRESSURE MOVES THROUGH NEW ENGLAND AND A WAVE OF LOW PRESSURE ON THE COLD FRONT BEGINS TO MOVE NORTH WIND GUSTS WILL AGAIN BE AT SMALL CRAFT LEVELS AND OCEAN SEAS WILL BUILD. WITH HIGH CONFIDENCE IN SMALL CRAFT CONDITIONS HAVE EXTENDED THE ADVISORY THROUGH TUESDAY. EXPECT SCA CONDS ON ALL WATERS TUE NIGHT...WITH MODERATE E FLOW BETWEEN DEPARTING STRONG HIGH PRESSURE AND AN APPROACHING WARM FRONT AND ACCOMPANYING WEAK SFC LOW. GUSTS ON THE OCEAN COULD APPROACH MINIMAL GALE FORCE...ESPECIALLY OUT EAST...AND SEAS COULD BUILDS AS HIGH AS 9 FT. SCA CONDS SHOULD THEN PERSIST ON THE OCEAN INTO WED-WED NIGHT AS THE WARM FRONT LIFTS TO THE N AND MODERATE SW FLOW AHEAD OF A COLD FRONT GUSTS UP TO 25 KT DURING THE DAY ON WED... FOLLOWED BY LINGERING SEAS ABOVE 5 FT WED NIGHT. GENERALLY QUIET CONDS EXPECTED FOR THU-FRI AS HIGH PRESSURE BUILDS IN...BUT OCEAN SEAS COULD APPROACH 5 FT FRI NIGHT AS NE FLOW SOUTH OF THE HIGH INCREASES. && .HYDROLOGY... NO SIGNIFICANT PRECIPITATION IS EXPECTED TODAY THROUGH TUESDAY MORNING. QPF WITH THE WARM FRONTAL APPROACH/PASSAGE FROM LATE DAY TUE INTO WED MORNING SHOULD BE ABOUT 3-4 TENTHS OF AN INCH. SOME OF THIS SHOULD FALL AS SNOW ACROSS INTERIOR LOCATIONS. NO HYDROLOGIC IMPACTS ARE EXPECTED. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST TUESDAY FOR ANZ350-353-355. && $$ SYNOPSIS...GOODMAN/MET NEAR TERM...TONGUE SHORT TERM...MET LONG TERM...GOODMAN AVIATION...BC MARINE...GOODMAN/MET HYDROLOGY...GOODMAN/MET
AREA FORECAST DISCUSSION
NWS JACKSON KY
943 AM EST MON DEC 1 2014 .UPDATE... ISSUED AT 943 AM EST MON DEC 1 2014 A FEW AREAS OF RAIN HAVE BEEN DEVELOPING OVER THE SOUTHERN PART OF THE FORECAST AREA AND OVER NORTHERN TN. AS SUCH HAVE ADDED A SLIGHT CHANCE OF RAIN IN THE SOUTH FOR THIS MORNING TO ACCOUNT FOR THIS. THE MAIN AREA OF RAIN WILL STILL BE SLOW TO REACH THE SOUTHERN PART OF THE FORECAST AREA. NDFD AND ZFP HAVE BEEN UPDATED. UPDATE ISSUED AT 639 AM EST MON DEC 1 2014 THE COLD FRONT IS BASICALLY PERFORMING AS FORECAST STRETCHING FROM LEX TO IOB TO SYM AT THE PRESENT TIME. HOWEVER...THE PROGRESSION OF THE RAIN TO THE SOUTH IS SLIGHTLY SLOWER THAN PREVIOUSLY THOUGHT AND THE LATEST HRRR RUNS ARE REALLY SLOW IN BREAKING OUT RAIN OVER OUR SOUTHEAST COUNTIES. SO...FINE TUNED THE HOURLY POP GRIDS TO SLOW DOWN THE SOUTHWARD PUSH A FEW HOURS. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 316 AM EST MON DEC 1 2014 THE COLD FRONT IS ON OUR DOORSTEP AT 3 AM HAVING JUST NOW PASSED THE MAYSVILLE MESONET STATION. THIS WILL PROGRESS STEADILY THROUGH OUR AREA THIS MORNING EXITING INTO VIRGINIA BY LATE AFTERNOON. RAIN SHOWERS CONTINUE TO BLOSSOM ALONG AND BEHIND THE FRONT. THESE WILL PROGRESS SLOWLY SOUTHEAST INTO OUR NORTHERN COUNTIES OVER THE NEXT FEW HOURS. THE RAIN MAY DIMINISH SOME LATER IN THE MORNING AS IT WORKS INTO THE HEART OF EAST KENTUCKY...BUT AN UPSTREAM SHORTWAVE SHOULD CAUSE IT TO EXPAND AGAIN LATE IN THE DAY AND INTO THE EVENING HOURS. THE OTHER IMPACTS BROUGHT BY THE PASSAGE OF THE FRONT WILL BE A QUICK SHIFT IN WINDS TO THE NORTHWEST...AND FALLING TEMPS. EARLY HIGHS AROUND 60 WILL END UP RANGING FROM THE UPPER 30S ALONG I-64 TO THE UPPER 40S ALONG THE VIRGINIA BORDER BY EARLY EVENING. THE OTHER CONCERN HAS BEEN THE THREAT FOR A BIT OF WINTRY PRECIP TONIGHT NORTH OF I-64. WHILE WE CANNOT RULE OUT A LITTLE INCONSEQUENTIAL SLEET DURING THE EVENING...WE DID NOT MENTION THIS IN THE FORECAST. WE DID KEEP A SLIGHT CHANCE OF FREEZING RAIN IN THE FORECAST NORTH OF I-64 LATE IN THE NIGHT AND EARLY TUESDAY MORNING AS THERE MAY BE A FEW POCKETS DROP TO FREEZING THERE. IF THE FREEZING PRECIP DOES OCCUR...ROAD TEMPS WOULD LIKELY NOT GET COLD ENOUGH FOR ANY WORRIES. ON TUESDAY...THE 850 MB FLOW RAMPS UP OVER THE STATE AND BACKS TO THE SOUTHWEST IN RESPONSE TO A SHORTWAVE DIVING INTO THE NORTHERN PLAINS. THIS WILL BEGIN TO PUSH THE SURFACE BOUNDARY BACK TO THE NORTH WITH TEMPERATURES OVER OUR SOUTHEAST COUNTIES WARMING WELL INTO THE 50S...WHILE OUR NORTHERN COUNTIES STRUGGLE TO REACH THE 40S. A LITTLE OVERRUNNING LIGHT RAIN AND DRIZZLE CAN BE EXPECTED THROUGHOUT THE DAY AS WELL. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 316 AM EST MON DEC 1 2014 ACTIVE WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE WEEK AND INTO THE UPCOMING WEEKEND. WHILE DIFFERENCES ARE EVIDENT IN THE MODELS...ONE THING THEY DO AGREE ON IS KEEPING A STALLED BOUNDARY ACROSS THE AREA INTO THURSDAY...AND KEEPING THE WEATHER UNSETTLED INTO SATURDAY. THIS WILL KEEP A FAIRLY GOOD TEMPERATURE/DEWPOINT GRADIENT ACROSS THE AREA FOR SEVERAL DAYS. THUS...TEMPERATURE FORECAST IS HIGHLY DEPENDENT WHERE THAT FRONT IS AT ANYTIME BETWEEN NOW AND THE WEEKEND AND WILL FEATURE PLENTY OF ROOM FOR TEMPERATURE TO GO UP OR DOWN FROM THE CURRENT FORECAST. IN THIS SCENARIO...A BLENDED FORECAST IS CERTAINLY A GOOD WAY TO GO...AND STAY AWAY FROM THE EXTREME HIGHS AND LOWS FOR NOW. CLOUD COVER WILL HANG TOUGH RIGHT THROUGH THE END OF THE WEEK WHICH WILL ALSO LIMIT THE DIURNAL RANGE IN TEMPERATURES. AS FAR AS RAIN CHANCES GO...WE MAY SEE SOME LIGHT RAIN/DRIZZLE HOLD ON THROUGH TUESDAY NIGHT INTO WEDNESDAY...ESPECIALLY ACROSS SOUTHEAST KENTUCKY. A BRIEF PERIOD OF SUBSIDENCE MAY SHALLOW OUT THE MOISTURE ENOUGH TO CUT OFF THE RAIN POTENTIAL FROM MIDDAY WEDNESDAY INTO WEDNESDAY NIGHT. HOWEVER...A MID LEVEL SHORTWAVE WILL PUSH EAST ON THURSDAY...BRINGING THE THREAT OF RAIN BACK INTO THE AREA. AT THIS POINT...MODELS DIFFER QUITE A BIT ON HOW THINGS PLAY OUT INTO THE UPCOMING WEEKEND...BUT REGARDLESS OF WHICH MODEL YOU BUY INTO... IT WILL REMAIN DAMP WITH RAIN CHANCES CONTINUING INTO SATURDAY. IT DOES LOOKS LIKE SOME POTENTIAL FOR US TO DRY OUT BY THE SECOND HALF OF THE WEEKEND...SO WILL TREND POPS DOWNWARD BY THE END OF THE PERIOD. AT THIS TIME...WHILE IT DOES LOOK DAMP INTO NEXT WEEKEND... PRECIPITATION AMOUNTS SHOULD REMAIN OVERALL FAIRLY LIGHT THROUGH THE PERIOD...WITH NO BIG SURGES OF HEAVY RAINFALL. THUS...IT DOES NOT LOOK LIKE WE SHOULD HAVE MUCH FLOODING CONCERNS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 639 AM EST MON DEC 1 2014 EXPECT DETERIORATING CONDITIONS FROM NORTHWEST TO SOUTHEAST TODAY AS A COLD FRONT PASSES THROUGH THE REGION. A BAND OF SHOWERS WILL ACCOMPANY THE FRONT WITH A WIND SHIFT TO THE NORTHWEST AND THEN NORTH. CEILINGS WILL DROP QUICKLY FROM VFR TO IFR BEHIND THE FRONT. WE CURRENTLY FORECAST THE FRONTAL PASSAGE TO TAKE PLACE AT THE FOLLOWING TIMES... SYM...11Z SME...15Z JKL...15Z LOZ...16Z SJS...16Z PBX...17Z W38...18Z I35...20Z 1A6...20Z AFTER THE FRONTAL PASSAGE...LOW CEILINGS AND LIGHT RAIN AND/OR DRIZZLE WILL PERSIST AT THE TAF SITES THROUGH THE REMAINDER OF THE PERIOD WITH WINDS CONTINUING TO VEER AROUND TO A NORTHEASTERLY DIRECTION. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SBH SHORT TERM...ABE LONG TERM...KAS AVIATION...ABE
AREA FORECAST DISCUSSION
NWS JACKSON KY
639 AM EST MON DEC 1 2014 .UPDATE... ISSUED AT 639 AM EST MON DEC 1 2014 THE COLD FRONT IS BASICALLY PERFORMING AS FORECAST STRETCHING FROM LEX TO IOB TO SYM AT THE PRESENT TIME. HOWEVER...THE PROGRESSION OF THE RAIN TO THE SOUTH IS SLIGHTLY SLOWER THAN PREVIOUSLY THOUGHT AND THE LATEST HRRR RUNS ARE REALLY SLOW IN BREAKING OUT RAIN OVER OUR SOUTHEAST COUNTIES. SO...FINE TUNED THE HOURLY POP GRIDS TO SLOW DOWN THE SOUTHWARD PUSH A FEW HOURS. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 316 AM EST MON DEC 1 2014 THE COLD FRONT IS ON OUR DOORSTEP AT 3 AM HAVING JUST NOW PASSED THE MAYSVILLE MESONET STATION. THIS WILL PROGRESS STEADILY THROUGH OUR AREA THIS MORNING EXITING INTO VIRGINIA BY LATE AFTERNOON. RAIN SHOWERS CONTINUE TO BLOSSOM ALONG AND BEHIND THE FRONT. THESE WILL PROGRESS SLOWLY SOUTHEAST INTO OUR NORTHERN COUNTIES OVER THE NEXT FEW HOURS. THE RAIN MAY DIMINISH SOME LATER IN THE MORNING AS IT WORKS INTO THE HEART OF EAST KENTUCKY...BUT AN UPSTREAM SHORTWAVE SHOULD CAUSE IT TO EXPAND AGAIN LATE IN THE DAY AND INTO THE EVENING HOURS. THE OTHER IMPACTS BROUGHT BY THE PASSAGE OF THE FRONT WILL BE A QUICK SHIFT IN WINDS TO THE NORTHWEST...AND FALLING TEMPS. EARLY HIGHS AROUND 60 WILL END UP RANGING FROM THE UPPER 30S ALONG I-64 TO THE UPPER 40S ALONG THE VIRGINIA BORDER BY EARLY EVENING. THE OTHER CONCERN HAS BEEN THE THREAT FOR A BIT OF WINTRY PRECIP TONIGHT NORTH OF I-64. WHILE WE CANNOT RULE OUT A LITTLE INCONSEQUENTIAL SLEET DURING THE EVENING...WE DID NOT MENTION THIS IN THE FORECAST. WE DID KEEP A SLIGHT CHANCE OF FREEZING RAIN IN THE FORECAST NORTH OF I-64 LATE IN THE NIGHT AND EARLY TUESDAY MORNING AS THERE MAY BE A FEW POCKETS DROP TO FREEZING THERE. IF THE FREEZING PRECIP DOES OCCUR...ROAD TEMPS WOULD LIKELY NOT GET COLD ENOUGH FOR ANY WORRIES. ON TUESDAY...THE 850 MB FLOW RAMPS UP OVER THE STATE AND BACKS TO THE SOUTHWEST IN RESPONSE TO A SHORTWAVE DIVING INTO THE NORTHERN PLAINS. THIS WILL BEGIN TO PUSH THE SURFACE BOUNDARY BACK TO THE NORTH WITH TEMPERATURES OVER OUR SOUTHEAST COUNTIES WARMING WELL INTO THE 50S...WHILE OUR NORTHERN COUNTIES STRUGGLE TO REACH THE 40S. A LITTLE OVERRUNNING LIGHT RAIN AND DRIZZLE CAN BE EXPECTED THROUGHOUT THE DAY AS WELL. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 316 AM EST MON DEC 1 2014 ACTIVE WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE WEEK AND INTO THE UPCOMING WEEKEND. WHILE DIFFERENCES ARE EVIDENT IN THE MODELS...ONE THING THEY DO AGREE ON IS KEEPING A STALLED BOUNDARY ACROSS THE AREA INTO THURSDAY...AND KEEPING THE WEATHER UNSETTLED INTO SATURDAY. THIS WILL KEEP A FAIRLY GOOD TEMPERATURE/DEWPOINT GRADIENT ACROSS THE AREA FOR SEVERAL DAYS. THUS...TEMPERATURE FORECAST IS HIGHLY DEPENDENT WHERE THAT FRONT IS AT ANYTIME BETWEEN NOW AND THE WEEKEND AND WILL FEATURE PLENTY OF ROOM FOR TEMPERATURE TO GO UP OR DOWN FROM THE CURRENT FORECAST. IN THIS SCENARIO...A BLENDED FORECAST IS CERTAINLY A GOOD WAY TO GO...AND STAY AWAY FROM THE EXTREME HIGHS AND LOWS FOR NOW. CLOUD COVER WILL HANG TOUGH RIGHT THROUGH THE END OF THE WEEK WHICH WILL ALSO LIMIT THE DIURNAL RANGE IN TEMPERATURES. AS FAR AS RAIN CHANCES GO...WE MAY SEE SOME LIGHT RAIN/DRIZZLE HOLD ON THROUGH TUESDAY NIGHT INTO WEDNESDAY...ESPECIALLY ACROSS SOUTHEAST KENTUCKY. A BRIEF PERIOD OF SUBSIDENCE MAY SHALLOW OUT THE MOISTURE ENOUGH TO CUT OFF THE RAIN POTENTIAL FROM MIDDAY WEDNESDAY INTO WEDNESDAY NIGHT. HOWEVER...A MID LEVEL SHORTWAVE WILL PUSH EAST ON THURSDAY...BRINGING THE THREAT OF RAIN BACK INTO THE AREA. AT THIS POINT...MODELS DIFFER QUITE A BIT ON HOW THINGS PLAY OUT INTO THE UPCOMING WEEKEND...BUT REGARDLESS OF WHICH MODEL YOU BUY INTO... IT WILL REMAIN DAMP WITH RAIN CHANCES CONTINUING INTO SATURDAY. IT DOES LOOKS LIKE SOME POTENTIAL FOR US TO DRY OUT BY THE SECOND HALF OF THE WEEKEND...SO WILL TREND POPS DOWNWARD BY THE END OF THE PERIOD. AT THIS TIME...WHILE IT DOES LOOK DAMP INTO NEXT WEEKEND... PRECIPITATION AMOUNTS SHOULD REMAIN OVERALL FAIRLY LIGHT THROUGH THE PERIOD...WITH NO BIG SURGES OF HEAVY RAINFALL. THUS...IT DOES NOT LOOK LIKE WE SHOULD HAVE MUCH FLOODING CONCERNS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 639 AM EST MON DEC 1 2014 EXPECT DETERIORATING CONDITIONS FROM NORTHWEST TO SOUTHEAST TODAY AS A COLD FRONT PASSES THROUGH THE REGION. A BAND OF SHOWERS WILL ACCOMPANY THE FRONT WITH A WIND SHIFT TO THE NORTHWEST AND THEN NORTH. CEILINGS WILL DROP QUICKLY FROM VFR TO IFR BEHIND THE FRONT. WE CURRENTLY FORECAST THE FRONTAL PASSAGE TO TAKE PLACE AT THE FOLLOWING TIMES... SYM...11Z SME...15Z JKL...15Z LOZ...16Z SJS...16Z PBX...17Z W38...18Z I35...20Z 1A6...20Z AFTER THE FRONTAL PASSAGE...LOW CEILINGS AND LIGHT RAIN AND/OR DRIZZLE WILL PERSIST AT THE TAF SITES THROUGH THE REMAINDER OF THE PERIOD WITH WINDS CONTINUING TO VEER AROUND TO A NORTHEASTERLY DIRECTION. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...ABE SHORT TERM...ABE LONG TERM...KAS AVIATION...ABE
AREA FORECAST DISCUSSION
NWS TULSA OK
532 AM CST MON DEC 1 2014 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. AREAS OF LIGHT FREEZING RAIN/DRIZZLE WILL CONTINUE PRIMARILY OVER NW AR TAF SITES THIS MORNING WITH IFR CONDITIONS/LOW CEILINGS. PRECIPITATION SHOULD BEGIN TO SHIFT EAST BY EARLY AFTERNOON...HOWEVER LOW CLOUDS WILL PERSIST ACROSS E OK/NW AR THIS AFTERNOON. SHOULD SEE SOME CLEARING OVERNIGHT FROM WEST TO EAST ACROSS EASTERN OKLAHOMA TONIGHT. && .PREV DISCUSSION... /ISSUED 418 AM CST MON DEC 1 2014/ DISCUSSION... A COLD FRONT WAS POSITIONED JUST SOUTH AND EAST OF THE CWA EARLY THIS MORNING WITH GUSTY NORTHERLY WINDS OF 15 TO 30 MPH AND MUCH COLDER TEMPERATURES COMMON ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS. TEMPS AS OF THIS WRITING WERE RUNNING CLOSE TO 20 TO 40 DEGREES COLDER COMPARED TO 24 HRS AGO. ALSO SOME SCATTERED LIGHT PRECIP HAD DEVELOPED OVER FAR NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS. A FREEZING LINE WAS LOCATED ALONG A LINE FROM NEAR EUFAULA TO SILOAM SPRINGS TO NEAR BERRYVILLE. PRECIP NORTH OF THIS LINE WAS FALLING AS LIGHT FREEZING DRIZZLE/FREEZING RAIN WITH SOME POSSIBLE LIGHT SLEET MIXED IN. PRECIP CHANCES WILL REMAIN POSSIBLE THROUGH THIS AFTERNOON...WITH GREATER CHANCES OVER NORTHWEST ARKANSAS THIS MORNING. THE FREEZING LINE IS EXPECTED TO CONTINUE TO SHIFT SOUTHEASTWARD THIS MORNING WITH PARTS OF FAR EASTERN OKLAHOMA INTO FAR NORTHWEST ARKANSAS HAVING THE POTENTIAL FOR SOME FREEZING PRECIP. LATEST HRRR AND LOCAL IN- HOUSE MODEL TRY TO DEVELOP ADDITIONAL PRECIP OVER FAR NORTHEAST OKLAHOMA INTO FAR NORTHWEST ARKANSAS AROUND MID MORNING BEFORE ENDING THIS AFTERNOON. THUS...WILL LET THE WINTER WEATHER ADVISORY RIDE AS IS...WITH THE POTENTIAL TO CANCEL EARLY IF ADDITIONAL PRECIP DOESNT DEVELOP. TOTAL ICE ACCUMULATIONS CONTINUE TO LOOK LIKE LESS THAN A TENTH OF AN INCH POSSIBLE OVER THE ADVISORY AREA. PRECIP SHOULD TAPER OFF FROM WEST TO EAST THIS AFTERNOON AND EXIT THE CWA BY THIS EVENING. TEMPERATURES TODAY WILL STRUGGLE TO REACH UP BACK UP TO AROUND THE FREEZING MARK ACROSS NORTHEAST/EAST CENTRAL OKLAHOMA AND ALSO FAR NORTHWEST ARKANSAS. TEMPS OVER SOUTHEAST OKLAHOMA INTO WEST CENTRAL ARKANSAS SHOULD CONTINUE TO DROP DURING THE MORNING HOURS AND REMAIN NEAR STEADY THIS AFTERNOON. CLOUDY SKIES AND GUSTY NORTHERLY WINDS WILL ALSO REMAIN COMMON THROUGH THE DAY FOR THE CWA. GUSTY WINDS COMBINED WITH DRIER AIR FILTERING INTO THE REGION WILL ALLOW FOR HIGH FIRE DANGERS FOR MUCH OF THE CWA AND ELEVATED FIRE DANGERS OVER NORTHEAST OKLAHOMA. A FIRE DANGER STATEMENT HAS BEEN ISSUED FOR NORTHEAST OKLAHOMA WHERE THE HIGHER WINDS AND GREATER FIRE SPREAD POTENTIAL ARE EXPECTED TO BE CO-LOCATED. OVERNIGHT TONIGHT...SKIES LOOK TO SCATTER OUT ACROSS THE WESTERN PART OF THE CWA...WHILE CLOUDY CONDITIONS REMAIN FOR THE EASTERN HALF. LIGHT WINDS UNDERNEATH A COLD CANADIAN HIGH PRESSURE MOVING THROUGH THE PLAINS WILL ALLOW FOR TEMPS TONIGHT TO FALL INTO THE 20S FOR MOST LOCATIONS...WITH SOME LOCATIONS OVER NORTHEAST OKLAHOMA POSSIBLY FALLING INTO THE TEENS. HIGH PRESSURE EXITS THE PLAINS TUESDAY ALLOWING FOR SOUTHERLY WINDS TO RETURN ACROSS THE CWA AND THE BEGINNING OF A TEMPERATURE WARMING TREND BACK UP TOWARD THE SEASONAL AVERAGE FOR THE SECOND HALF OF THE WEEK. A FRONTAL BOUNDARY IS FORECAST TO LIFT INTO THE REGION TUESDAY NIGHT AND WEDNESDAY AND REMAIN NEARLY STATIONARY THROUGH THE WEEK WHILE UPPER LEVEL ZONAL FLOW PUSHES A SERIES OF WEAK SHORTWAVE THROUGH THE PLAINS. THE RESULT WILL BE AT LEAST SLIGHT CHANCES FOR RAIN SHOWERS TO BE POSSIBLE WEDNESDAY INTO THE WEEKEND. A SLIGHTLY MORE DEFINED WAVE MOVING THROUGH FRIDAY COULD CREATE AN ISOLATED THUNDERSTORM OR TWO. && .TSA WATCHES/WARNINGS/ADVISORIES... OK...WINTER WEATHER ADVISORY UNTIL 4 PM MONDAY FOR OKZ068-OKZ069. AR...WINTER WEATHER ADVISORY UNTIL 4 PM MONDAY FOR ARZ001-ARZ002- ARZ010-ARZ011. && $$ AVIATION...12
AREA FORECAST DISCUSSION
NWS TULSA OK
418 AM CST MON DEC 1 2014 .DISCUSSION... A COLD FRONT WAS POSITIONED JUST SOUTH AND EAST OF THE CWA EARLY THIS MORNING WITH GUSTY NORTHERLY WINDS OF 15 TO 30 MPH AND MUCH COLDER TEMPERATURES COMMON ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS. TEMPS AS OF THIS WRITING WERE RUNNING CLOSE TO 20 TO 40 DEGREES COLDER COMPARED TO 24 HRS AGO. ALSO SOME SCATTERED LIGHT PRECIP HAD DEVELOPED OVER FAR NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS. A FREEZING LINE WAS LOCATED ALONG A LINE FROM NEAR EUFAULA TO SILOAM SPRINGS TO NEAR BERRYVILLE. PRECIP NORTH OF THIS LINE WAS FALLING AS LIGHT FREEZING DRIZZLE/FREEZING RAIN WITH SOME POSSIBLE LIGHT SLEET MIXED IN. PRECIP CHANCES WILL REMAIN POSSIBLE THROUGH THIS AFTERNOON...WITH GREATER CHANCES OVER NORTHWEST ARKANSAS THIS MORNING. THE FREEZING LINE IS EXPECTED TO CONTINUE TO SHIFT SOUTHEASTWARD THIS MORNING WITH PARTS OF FAR EASTERN OKLAHOMA INTO FAR NORTHWEST ARKANSAS HAVING THE POTENTIAL FOR SOME FREEZING PRECIP. LATEST HRRR AND LOCAL IN- HOUSE MODEL TRY TO DEVELOP ADDITIONAL PRECIP OVER FAR NORTHEAST OKLAHOMA INTO FAR NORTHWEST ARKANSAS AROUND MID MORNING BEFORE ENDING THIS AFTERNOON. THUS...WILL LET THE WINTER WEATHER ADVISORY RIDE AS IS...WITH THE POTENTIAL TO CANCEL EARLY IF ADDITIONAL PRECIP DOESNT DEVELOP. TOTAL ICE ACCUMULATIONS CONTINUE TO LOOK LIKE LESS THAN A TENTH OF AN INCH POSSIBLE OVER THE ADVISORY AREA. PRECIP SHOULD TAPER OFF FROM WEST TO EAST THIS AFTERNOON AND EXIT THE CWA BY THIS EVENING. TEMPERATURES TODAY WILL STRUGGLE TO REACH UP BACK UP TO AROUND THE FREEZING MARK ACROSS NORTHEAST/EAST CENTRAL OKLAHOMA AND ALSO FAR NORTHWEST ARKANSAS. TEMPS OVER SOUTHEAST OKLAHOMA INTO WEST CENTRAL ARKANSAS SHOULD CONTINUE TO DROP DURING THE MORNING HOURS AND REMAIN NEAR STEADY THIS AFTERNOON. CLOUDY SKIES AND GUSTY NORTHERLY WINDS WILL ALSO REMAIN COMMON THROUGH THE DAY FOR THE CWA. GUSTY WINDS COMBINED WITH DRIER AIR FILTERING INTO THE REGION WILL ALLOW FOR HIGH FIRE DANGERS FOR MUCH OF THE CWA AND ELEVATED FIRE DANGERS OVER NORTHEAST OKLAHOMA. A FIRE DANGER STATEMENT HAS BEEN ISSUED FOR NORTHEAST OKLAHOMA WHERE THE HIGHER WINDS AND GREATER FIRE SPREAD POTENTIAL ARE EXPECTED TO BE CO-LOCATED. OVERNIGHT TONIGHT...SKIES LOOK TO SCATTER OUT ACROSS THE WESTERN PART OF THE CWA...WHILE CLOUDY CONDITIONS REMAIN FOR THE EASTERN HALF. LIGHT WINDS UNDERNEATH A COLD CANADIAN HIGH PRESSURE MOVING THROUGH THE PLAINS WILL ALLOW FOR TEMPS TONIGHT TO FALL INTO THE 20S FOR MOST LOCATIONS...WITH SOME LOCATIONS OVER NORTHEAST OKLAHOMA POSSIBLY FALLING INTO THE TEENS. HIGH PRESSURE EXITS THE PLAINS TUESDAY ALLOWING FOR SOUTHERLY WINDS TO RETURN ACROSS THE CWA AND THE BEGINNING OF A TEMPERATURE WARMING TREND BACK UP TOWARD THE SEASONAL AVERAGE FOR THE SECOND HALF OF THE WEEK. A FRONTAL BOUNDARY IS FORECAST TO LIFT INTO THE REGION TUESDAY NIGHT AND WEDNESDAY AND REMAIN NEARLY STATIONARY THROUGH THE WEEK WHILE UPPER LEVEL ZONAL FLOW PUSHES A SERIES OF WEAK SHORTWAVE THROUGH THE PLAINS. THE RESULT WILL BE AT LEAST SLIGHT CHANCES FOR RAIN SHOWERS TO BE POSSIBLE WEDNESDAY INTO THE WEEKEND. A SLIGHTLY MORE DEFINED WAVE MOVING THROUGH FRIDAY COULD CREATE AN ISOLATED THUNDERSTORM OR TWO. && .PRELIMINARY POINT TEMPS/POPS... TUL 32 21 44 36 / 10 0 0 10 FSM 39 30 49 40 / 30 10 0 10 MLC 33 20 47 41 / 10 0 0 10 BVO 33 17 43 30 / 0 0 0 0 FYV 31 25 44 36 / 30 10 0 10 BYV 30 24 44 36 / 40 10 0 10 MKO 32 23 44 38 / 10 0 0 10 MIO 31 22 43 32 / 20 0 0 10 F10 32 21 45 39 / 10 0 0 10 HHW 39 27 49 42 / 20 10 0 10 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...WINTER WEATHER ADVISORY UNTIL 4 PM MONDAY FOR OKZ068-OKZ069. AR...WINTER WEATHER ADVISORY UNTIL 4 PM MONDAY FOR ARZ001-ARZ002- ARZ010-ARZ011. && $$ SHORT TERM...12 LONG TERM....20
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
515 AM CST MON DEC 1 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 206 AM CST MON DEC 1 2014 CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED TROUGHS ALONG THE BRITISH COLUMBIA COAST AND FROM NORTHERN ONTARIO INTO CENTRAL MN....WITH WEAK RIDGING IN-BETWEEN OVER MONTANA AND ALBERTA. SOME PACIFIC MOISTURE WAS STREAMING INTO SOUTHERN PORTIONS OF THE FORECAST AREA AHEAD OF THE CENTRAL MN TROUGH... MANIFESTING ITSELF AS HIGH CLOUDS. CLEAR SKIES DOMINATE THE REST OF THE FORECAST AREA INTO THE NORTHERN PLAINS...RESULTING FROM A DRY ARCTIC AIRMASS IN PLACE. PRECIPITABLE WATER VALUES OF 0.10 INCHES OR LESS...20 TO 40 PERCENT OF NORMAL...WERE OBSERVED ON 00Z SOUNDINGS. MEANWHILE...925MB TEMPS WERE IN THE -15 TO -18C RANGE. THE COMBINATION OF THE CLEAR SKIES...DRY AIR...NIGHT TIME COOLING AND SOME SNOWPACK HAS ALLOWED READINGS TO DIP INTO THE SINGLE DIGITS BELOW ZERO ACROSS PORTIONS OF SOUTHEAST MN AND NORTH CENTRAL WI...AND SINGLE DIGITS ABOVE ZERO TO MID TEENS ELSEWHERE. A PERSISTENT 5 TO 15 MPH BREEZE HAS RESULTED IN WIND CHILLS OF ZERO TO 15 BELOW ZERO. THE SURFACE HIGH ASSOCIATED WITH THE ARCTIC AIR WAS STILL SITUATED OVER THE DAKOTAS. VERY CHILLY CONDITIONS START OFF THE FIRST DAY OF DECEMBER. ALTHOUGH PLENTY OF SUNSHINE IS EXPECTED AS THE SURFACE HIGH OVER THE DAKOTAS EVENTUALLY MOVES OVERHEAD BY SUNSET...925MB TEMPS IN THE -16C SOUTH TO -20C NORTH AT 18Z WILL LIMIT TEMPERATURES FROM CLIMBING TOO MUCH. 2 METER MODEL OUTPUT AND VARIOUS MOS GUIDANCE ARE ALL IN VERY GOOD AGREEMENT FOR TODAYS HIGHS...WITH READINGS MAINLY BETWEEN 5 AND 15 ABOVE. SHOULD THESE COME TO PASS...WE ARE LOOKING AT ONE OF THE TOP 5 COLDEST HIGHS FOR DECEMBER 1ST. WIND CHILLS WILL REMAIN AN ISSUE TO CONTEND WITH THIS MORNING AS THE 5 TO 15 MPH BREEZE PERSISTS. EXPECT DIMINISHING WINDS IN THE AFTERNOON COMBINED WITH CLIMBING TEMPERATURES TO HELP IMPROVE WIND CHILLS. CLEAR SKIES...VERY DRY AIR AND LIGHT WINDS EARLY THIS EVENING WITH THE SURFACE HIGH IN PLACE SHOULD PROMOTE A RAPID TEMPERATURE DROP AFTER SUNSET. SOME LOCATIONS COULD SEE A DROP OF 10 TO 15 DEGREES BETWEEN 21-00Z. MODELS ARE IN GOOD AGREEMENT PUSHING THE HIGH QUICKLY OFF TO THE EAST DURING THE NIGHT...MOVING INTO EASTERN WI BY 06Z AND LOWER MI BY 12Z. THIS ALLOWS THE GRADIENT TO TIGHTEN UP AND THUS AN INCREASE OF SOUTHERLY WINDS TO BRING WARMER AIR BACK INTO THE REGION. THE PROBLEM WE COULD RUN INTO IS WIND CHILLS BACK DOWN TO ADVISORY CRITERIA OF -20...DUE TO THE ONSET OF THE WINDS WITH THE COLD TEMPERATURES IN THE EVENING. THUS...ANOTHER WIND CHILL ADVISORY MAY BE NEEDED FOR SOME AREAS AFTER THE CURRENT ONE ENDS. TAYLOR COUNTY APPEARS TO BE THE BEST CANDIDATE FOR AN ADVISORY WITH SOME OF SOUTHEAST MN PERHAPS NEEDING INCLUSION AS WELL. AN INCREASING MID CLOUD DECK TOWARDS 12Z ACCOMPANYING THE WARM ADVECTION SHOULD ALSO HELP TO GIVE TEMPERATURES A BOOST. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 206 AM CST MON DEC 1 2014 FOCUS/ATTENTION FOR THE TUESDAY THROUGH WEDNESDAY TIME PERIOD REMAINS ON THE CURRENT UPPER TROUGH ALONG THE BRITISH COLUMBIA COAST. MODEL AGREEMENT REMAINS GOOD BRINGING THIS TROUGH ACROSS THE NORTHERN PLAINS TUESDAY...ITS AXIS OVER THE FORECAST AREA BY 12Z WEDNESDAY...AND OFF INTO THE EASTERN GREAT LAKES BY 00Z THU. AHEAD OF THE TROUGH FOR TUESDAY...A BRISK SOUTHWEST WIND WILL HELP TO BOOST 925MB TEMPS UP TO -5 TO -8C BY 00Z. THESE READINGS COMBINED WITH SOME SUN FILTERED THROUGH PERIODS OF MID/HIGH CLOUDS SUPPORT HIGHS IN THE 20S TO LOW 30S...WARMEST IN FAR SOUTHWEST WI AND RIVER VALLEYS WHERE SNOW COVER IS LIMITED. AS WE HEAD INTO THE LATE AFTERNOON AND EVENING HOURS...MODEL DISAGREEMENT BEGINS TO SHOW UP NORTH OF I-90 IN THE PRECIPITATION DEPARTMENT. THE 01.00Z NAM AND REGIONAL CANADIAN MODELS WANT TO PRODUCE SOME LIGHT SNOW... ESPECIALLY NORTH OF I-94. THE 01.00Z GFS AND FOR THE MOST PART THE 01.00Z ECMWF ARE DRY. BOTH MODEL GROUPS DEPICT WEAK ISENTROPIC LIFTING IN THE 900-600MB LAYER...BUT THE DIFFERENCE IS THAT THE NAM/REGIONAL CANADIAN HAVE MORE MOISTURE IN THE 900-700MB LAYER. HARD TO SAY AT THIS POINT WHAT THAT LAYER MOISTURE WILL LOOK LIKE SO MAINTAINED SOME LOW CHANCES OF PRECIPITATION NORTH OF I-94 FOR THE LATE AFTERNOON/EVENING HOURS. ANY SNOW SHOULD PUSH OFF TO THE EAST AFTER 06Z AS THE UPPER TROUGH AXIS MOVES IN AND A COLD FRONT PASSES THROUGH. THIS COLD FRONT WILL USHER IN SLIGHTLY COOLER AIR FOR WEDNESDAY AS 925MB TEMPS FALL TO -6 TO -10C. THERE SHOULD BE PLENTY OF SUN ON WEDNESDAY AS DRY AIR AND SUBSIDENCE MOVES IN BEHIND THE UPPER TROUGH...SO HIGHS ARE EXPECTED TO BE NEAR OR JUST A LITTLE COOLER THAN TUESDAY. FROM WEDNESDAY NIGHT THROUGH FRIDAY...THE UPPER FLOW IS PROGGED TO BECOME MORE ZONAL...WITH NORTHERN AND SOUTHERN STREAMS BECOMING MORE EVIDENT. THE NORTHERN STREAM LOOKS TO TRACK ACROSS SOUTHERN CANADA WHILE THE SOUTHERN STREAM BECOMES POSITIONED ACROSS THE SOUTHERN U.S.. THE IMPACT TO THE FORECAST AREA FROM THE POSITIONS OF THESE STREAMS IS A WARMING TREND AS PACIFIC AIR FLOWS EASTWARD...AS WELL AS DRY CONDITIONS WITH THE SOUTHERN STREAMING BLOCKING GULF MOISTURE. THERE IS ONE SMALL OPPORTUNITY DURING THIS PERIOD TO PICK UP SOME LIGHT SNOW AND THAT IS ON THURSDAY FROM THE 30.00Z/12Z AND 01.00Z ECMWF. THE ECMWF SUGGESTS A DECENT SHORTWAVE AS WELL AS BAND OF MID LEVEL FRONTOGENESIS AND MOISTURE TO HELP PRODUCE THE SNOW. HOWEVER...ALL OTHER GUIDANCE IS DRY...SUGGESTING THE DRY AIR THAT CAME IN ON WEDNESDAY WILL BE ENOUGH TO ABSORB ANY SNOW FALLING OUT OF THE MID CLOUD. CONSIDERED LEAVING THURSDAY DRY...BUT THE ECMWF CONTINUITY IS CONCERNING. THEREFORE...HAVE ADDED A 20 PERCENT CHANCE TO LOCATIONS NORTH OF I-90. THURSDAYS HIGHS MAY NOT BE MUCH DIFFERENT THAN WEDNESDAY DUE TO CLOUDS MOVING IN AND WARM ADVECTION JUST BEGINNING TO GET IN EARNEST. BETTER SHOT FOR WARMER CONDITIONS COMES FRIDAY AS 925MB TEMPS REACH -2 TO -4C. THOSE READINGS COULD SUPPORT 30S TO LOW 40S...BUT IT APPEARS WE WILL BE BATTLING LOW STRATUS PER ECMWF/GFS 925MB RH FIELDS NEAR SATURATION...THUS HAVE TEMPERED HIGHS SOME. HEADING INTO THE WEEKEND...THE SPLIT FLOW REGIME CONTINUES...WITH HIGH PRESSURE PROGGED AT THE SURFACE. THUS...WE SHOULD SEE A CONTINUATION OF DRY CONDITIONS. SOME DISCREPANCIES EXIST ON HOW WARM THE WEEKEND WILL BE...AND IN PARTICULAR SATURDAY WHERE THE ECMWF DRIVES A LITTLE BIT MORE COLD AIR INTO THE REGION COMPARED TO THE GFS. NEVERTHELESS...READINGS SHOULD BE CLOSE TO NORMAL ON SATURDAY WITH MORE CONFIDENCE OF ABOVE NORMAL ON SUNDAY AS 925MB TEMPS THEN CLIMB TO AT LEAST 0C...IF NOT SLIGHTLY HIGHER. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 515 AM CST MON DEC 1 2014 GOOD VFR CONDITIONS EXPECTED TODAY/TONIGHT AS COLD AND DRY CANADIAN/ ARCTIC HIGH PRESSURE DRIFTS ACROSS THE UPPER MIDWEST. NORTHWEST WINDS 8-12 KTS WILL GIVE WAY TO LIGHTER/VARIABLE WINDS THIS AFTERNOON AS THE CENTER OF THE HIGH DRIFTS ACROSS THE AREA. WINDS THEN SWING SOUTHEAST/SOUTH AND INCREASE TONIGHT AS THE HIGH MOVES EAST OF THE REGION AND THE PRESSURE GRADIENT OVER THE AREA TIGHTENS AHEAD OF THE NEXT LOW/TROUGH MOVES INTO THE NORTHERN PLAINS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR WIZ017-029- 032>034-042. MN...WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR MNZ079-086- 087-094-095. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...04
AREA FORECAST DISCUSSION
NWS NEW YORK NY
356 PM EST MON DEC 1 2014 .SYNOPSIS... WEAK LOW PRESSURE OFF THE CAROLINA COAST ON TUESDAY MOVES NORTH ACROSS THE REGION LATE TUESDAY NIGHT. ANOTHER COLD FRONT PASSES WEDNESDAY AFTERNOON WITH STRONG HIGH PRESSURE BUILDING IN FOR THURSDAY. A STATIONARY FRONTAL BOUNDARY WILL THEN SET UP OVER THE AREA FRIDAY THRU THE WEEKEND. && .NEAR TERM /UNTIL MIDNIGHT TONIGHT/... THE COLD FRONT IS NOW PASSING ACROSS EASTERN LONG ISLAND. COLD AIR STILL WELL BEHIND THE FRONT. HRRR HAS GONE BAD WITH THE PCPN OVER CENTRAL PA. BASED ON EXTRAPOLATION, EXPECT THIS LIGHT PCPN IN NYC AROUND 6 PM. THE PCPN IS MOVING QUICKLY...THUS STILL EXPECTING IT OUT OF THE REGION BEFORE MIDNIGHT. LIFT COMES FROM JET DYNAMICS OF THE 140+ KT JET`S RIGHT REAR ENTRANCE REGION. PCPN IS JUST A FEW HUNDREDS. && .SHORT TERM /MIDNIGHT TONIGHT THROUGH TUESDAY NIGHT/... HIGH PRESSURE PASSES EAST ACROSS QUEBEC OVERNIGHT INTO TOMORROW MORNING WHICH QUICKLY VEERS WINDS TO EAST AS WEAK LOW PRESSURE FORMS OFF THE COAST OF NORFOLK. ALL NWP APPEARS CONSISTENT WITH LIGHT PCPN MOVING IN BEFORE SUNSET. THERMAL PROFILES SUPPORT A BRIEF MIX AT THE START FOR THE COAST WITH SNOW INLAND. THE SOUTHEAST VEERING FLOW QUICKLY WARMS TEMPS ALOFT RESULTING IN A WINTRY MIX INLAND AS WELL BY 8 PM OR SO. THE PROBLEM IS THAT THE COLD AIR WILL LIKELY HOLD AT THE SURFACE UNTIL MIDNIGHT OR FEW HOURS AFTER SUCH THAT FREEZING RAIN BECOMES A TRAVEL PROBLEM. WE DO EXPECT THE VAST MAJORITY OF THE INTERIOR TO BE ABOVE FREEZING BY SUNRISE. A WINTER WEATHER ADVISORY WILL LIKELY BE NEEDED FOR THE INTERIOR. BASED ON COLLABORATION WITH SURROUNDING NWS OFFICES...WE`LL ISSUE THESE ON THE MIDNIGHT SHIFT (ASSUMING THE FORECAST DOES NOT CHANGE). ACCUMULATION OF SNOW OVER THE INTERIOR IS LESS THAN AN INCH AND PROBABILISTIC SNOW DATA HAS BEEN ISSUED. ICE ACCUMULATION OF LESS THAN A TENTH OF AN INCH OR LESS IS FORECAST. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... THE UPR JET WILL ALLOW FOR GENERALLY ZONAL FLOW ALOFT THRU THE LONG TERM. ON WED...THE CWA WILL ENTER THE WARM SECTOR BRIEFLY AS A WRMFNT LIFTS TO THE N. THIS WILL CUT OFF THE STEADY RAIN...BUT ALLOW FOR SOME POCKETS OF LIGHT RAIN AND DZ TO DEVELOP. SOME PATCHY FG WILL ALSO BE POSSIBLE. TEMPS ABOUT 5 DEGREES ABV NORMAL. THE CDFNT COMES THRU WED NGT. THIS USHERS THE HIGHER HUMIDITY OFFSHORE...AND CLEARS OUT THE SKIES FOR THU. TEMPS ON THU BLW CLIMO BY A FEW DEGREES. THE CWA IS THEN IN THE BATTLE ZONE BETWEEN THE DEPARTING 1040S HI OVER ERN CANADA...AND SWLY FLOW ALOFT PRODUCING SOME WAA AND WEAK MOISTURE TRANSPORT. THIS WILL KEEP IT MAINLY CLOUDY FRI THRU THE WEEKEND...WITH PERIODS OF PCPN. ALL AREAS SUSCEPTIBLE TO SNOW OR A WINTRY MIX TO START OUT THE PCPN FRI...THEN THE COASTS AND CITY APPEAR TO TRANSITION TO MAINLY ALL RAIN FOR THE REMAINDER OF THE PERIOD. THE INTERIOR WILL STRUGGLE BOTH TO WARM INITIALLY...AND THEREAFTER STAY ABV FREEZING. AS A RESULT...A WINTRY MIX HAS BEEN INCLUDED IN THE FCST THRU THE WEEKEND. THE UNSETTLED PATTERN MAY END WITH WEAK LOW PRES DEVELOPING AND THEN FINALLY TRACKING OUT TO SEA. THE ROUGH TIMING FOR THIS IS MON...ALTHOUGH IT IS TOO FAR OUT TO PIN DOWN ATTM. THIS SCENARIO WOULD RESULT IN MORE RAIN AT THE COASTS AND A MIX AGAIN ACROSS THE INTERIOR. BECAUSE THIS SETUP WOULD BE MORE CONDUCIVE TO COOLING ALOFT...THE INTERIOR WOULD RUN THE THREAT FOR A CHANGEOVER TO ALL SNOW WITH SOME ACCUMS. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... COLD FRONT CONTINUES TO WORK ITS WAY ACROSS THE TERMINALS. WINDS HAVE BEGUN TO SHIFT TO THE NW...AND THAT TREND WILL CONTINUE THROUGH 22Z. WINDS INCREASE TO 10-15 KT WITH 15-20 KT GUSTS DURING THE EARLY EVENING. GUSTS END BY MIDNIGHT TONIGHT...AND WINDS GRADUALLY DIMINISH TO 8-12 KT THROUGH THE OVERNIGHT. WINDS CONTINUE TO VEER TO THE NE...AND EVENTUALLY TO THE E...ON TUESDAY AT 8-12 KT. MAINLY VFR CONDS...BUT THERE MAY BE SOME BRIEF POCKETS OF MVFR CONDS IN LIGHT RAIN AS THE FRONT MOVES ACROSS THE REGION. WILL ADD SOME -RA TO THE TAFS FROM AROUND 23Z-04Z...BUT WILL KEEP CONDS VFR. BEST CHANCES FOR MVFR CIGS WILL BE AT KSWF. ...NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP://WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: ANY GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA FROM 23Z-04Z. KLGA FCSTER COMMENTS: ANY GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA FROM 23Z-04Z. KEWR FCSTER COMMENTS: ANY GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA FROM 23Z-04Z. KTEB FCSTER COMMENTS: ANY GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA FROM 23Z-04Z. KHPN FCSTER COMMENTS: ANY GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA FROM 23Z-04Z. KISP FCSTER COMMENTS: ANY GUSTS MAY END PRIOR TO 05Z. LOW CHANCE FOR MVFR CONDS IN -RA FROM 00Z-05Z. .OUTLOOK FOR 21Z TUESDAY THROUGH SATURDAY... .TUESDAY...MVFR OR LOW CONDS POSSIBLE LATE AFTERNOON IN -RASN. .TUESDAY NIGHT...WINTRY MIX. RASN ALONG COAST CHANGES TO RAIN EARLY IN THE EVENING. ACROSS INTERIOR...CHANGEOVER WILL BE SLOWER...AS SN MIXES WITH SLEET/FREEZING RAIN BEFORE CHANGING TO FREEZING RAIN. .WEDNESDAY...SUB-VFR POSSIBLE IN -RA/DZ/FG IN THE MORNING. IMPROVING CONDS LATE. .THURSDAY...VFR. .FRIDAY...LIGHT RAIN AND/OR SNOW POSSIBLE IN THE AFTERNOON. .FRIDAY NIGHT...CHANCE FOR RAIN ALONG THE COAST AND SNOW/SLEET/FREEZING RAIN ACROSS INTERIOR. .SATURDAY...CHANCE FOR RAIN ALONG THE COAST AND SNOW/SLEET/FREEZING RAIN FOR INTERIOR IN THE MORNING...THEN CHANCE FOR RAIN IN THE AFTERNOON. && .MARINE... THE COLD FRONT IS PASSING EAST OF THE WATERS EARLY THIS EVENING. WINDS INCREASE SUCH THAT ALL WATERS ARE NOW UNDER A SCA DUE TO STRONG COLD ADVECTION THIS EVENING. SCA CONDITION REMAIN ON THE WATERS ON TUESDAY AND WILL LIKELY NEED EXTENDING INTO TUESDAY NIGHT. WINDS INCREASE AHEAD OF A CDFNT WED. SCA SPEEDS LIKELY...ESPECIALLY ERN WATERS. THE WINDS SHIFT WITH THE FRONT WED NGT...THEN DECREASE BLW SCA LVLS THU. WINDS AND SEAS WILL THEN LIKELY REMAIN BLW SCA LVLS TIL SUN. THEREAFTER...THE POTENTIAL DEVELOPMENT OF LOW PRES MAY BRING WINDS AND SEAS TO SCA LVLS...PARTICULARLY ON THE OCEAN. && .HYDROLOGY... NO SIGNIFICANT PRECIPITATION IS EXPECTED TODAY THROUGH TUESDAY MORNING. QPF LATE DAY TUE INTO WED MORNING SHOULD BE ABOUT A THIRD OF AN INCH. A WINTRY MIX OVER THE INTERIOR IS FORECAST AND NO HYDROLOGIC IMPACTS ARE EXPECTED. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO MIDNIGHT EST TONIGHT FOR ANZ330-335-338-340-345. SMALL CRAFT ADVISORY UNTIL 6 PM EST TUESDAY FOR ANZ350-353-355. && $$ SYNOPSIS...JMC/TONGUE NEAR TERM...TONGUE SHORT TERM...TONGUE LONG TERM...JMC AVIATION...MPS MARINE...JMC/TONGUE HYDROLOGY...TONGUE
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1252 PM EST MON DEC 1 2014 .SYNOPSIS... HIGH PRESSURE OVER EASTERN CANADA PUSHES A COLD FRONT ACROSS THE REGION THIS AFTERNOON. WEAK LOW PRESSURE OFF THE CAROLINA COAST ON TUESDAY AND MOVES NORTH ACROSS THE REGION LATE TUESDAY NIGHT. ANOTHER COLD FRONT PASSES WEDNESDAY AFTERNOON WITH STRONG HIGH PRESSURE BUILDING IN FOR THURSDAY. A PROLONGED PERIOD OF UNSETTLED WEATHER IS POSSIBLE FROM FRIDAY THROUGH NEXT WEEKEND. && .NEAR TERM /UNTIL MIDNIGHT TONIGHT/... CLOUDS CONTINUE TO INCREASE WITH THE COLD FRONT NOW ACROSS ORANGE COUNTY AND APPROACHING THE NY METRO. TEMPS ARE AT OR NEAR THEIR MAX AT THE CURRENT TIME WITH LOWER 60S FOR THE NY METRO...LONG ISLAND AN THE CT RIVER VALLEY. HRRR, NARRE-TL AND RAP ALL CONTINUE TO SUGGESTING LIGHT RA IS LIKELY FOR THE EVENING. START TIME IS ABOUT 5 PM IN NYC AND THEN SPREADS ACROSS LONG ISLAND. POPS WERE RAISED TO 60%. LIFT COMES FROM JET DYNAMICS OF THE 140+ KT JET`S RIGHT REAR ENTRANCE REGION. PCPN IS JUST A FEW HUNDREDS. && .SHORT TERM /MIDNIGHT THROUGH 6 PM TUESDAY/... RAIN ENDS BEFORE MIDNIGHT OVER LONG ISLAND. UPPER FLOW BECOMES MORE ZONAL TONIGHT INTO TUESDAY...THEN A SHORTWAVE MOVES THROUGH THE NORTHERN STREAM FLOW TUESDAY AFTERNOON. AT THE SURFACE HIGH PRESSURE MOVES THROUGH THE GREAT LAKES AND NEW ENGLAND TONIGHT THROUGH TUESDAY. AGAIN GUIDANCE IS SIMILAR WITH THE HIGH. WITH THE HIGH TO THE NORTH A STRONG NORTHEAST TO EAST FLOW DEVELOPS AND COLD AIR DAMMING OCCURS. TUESDAY AFTERNOON A WAVE OF LOW PRESSURE DEVELOPS OFF THE CAROLINA COAST ON THE OLD FRONTAL BOUNDARY AS A SOUTHERN STREAM SHORTWAVE REACHES THE SOUTHEAST. THE LOW THEN MOVES NORTH ALONG THE COAST INTO THE COLD AIR. WITH THE STRONG HIGH TO THE NORTH THE GFS ERODES THE COLD AIR TOO QUICKLY...WHILE THE NAM AND ECMWF HOLD ON TO THE COLD AIR. LEANED TOWARD THE COLDER SOLUTIONS FOR PRECIPITATION TYPE WITH CHANCE POPS BY LATE TUESDAY. FOR TEMPERATURES ALSO LEANED TOWARD THE COOLER NAM AND ECS GUIDANCE FOR LOWS TONIGHT AND HIGHS TUESDAY. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... A WARM FRONT AND ACCOMPANYING WEAK SFC WAVE LIFTING NE ALONG THE COAST WILL BRING STEADY PCPN TO THE AREA TUE NIGHT. PCPN SHOULD BEGIN AS SNOW INLAND...THEN QUICKLY TRANSITION OVER TO MIXED PCPN AND THEN RAIN IN MOST PLACES BY LATE TUE EVENING AS TEMPS WARM ALOFT. THE EXCEPTION WILL BE WELL INLAND IN PLACES SUCH AS ORANGE... W PASSAIC...PUTNAM AND N FAIRFIELD COUNTIES...WHERE COLD AIR DAMMING IN THE WAKE OF A DEPARTING 1045 MB WILL LOCK IN SUB- FREEZING AIR... WITH SNOW TRANSITIONING TO LIGHT FREEZING RAIN. THE PCPN EVENT SHOULD BE LIGHT...SO ATTM DO NOT EXPECT MUCH MORE THAN AN UP TO AN INCH OF LIGHT SNOW INLAND...AND A LIGHT GLAZE OF ICE IN THE AREAS WHERE FREEZING RAIN DOES OCCUR. AS THE WARM FRONT LIFTS N WED MORNING...PCPN SHOULD QUICKLY TRANSITION TO LIGHT RAIN OR DRIZZLE...AND SW FLOW SHOULD BRING IN MILER AIR...WITH HIGHS IN THE LOWER/MID 50S THROUGHOUT PER WARMEST MOS GUIDANCE...A FEW DEG ABOVE NORMAL. A COLD FRONT SHOULD QUICKLY FOLLOW LATE WED AFTERNOON OR WED EVENING...WITH LOW TEMPS IN THE 30S WED NIGHT. AS AN UPPER TROUGH SWINGS E ACROSS NEW ENGLAND AN ERN CANADA...INCREASING SFC CONFLUENCE IN ITS WAKE WILL LEAD TO DEVELOPMENT OF STRONG HIGH PRESSURE OVER THE NRN PLAINS WED NIGHT THAT BUILDS E-WARD TOWARD THE AREA THU-FRI...WITH BELOW NORMAL TEMPS. AS THIS SECOND STRONG HIGH DEPARTS...WILL SEE A SCENARIO SIMILAR TO THAT OF TUE NIGHT UNFOLD FOR FRI NIGHT-SAT AS ANOTHER FRONTAL SYSTEM APPROACHES FROM THE SW...WITH WARMING ALOFT AND SFC COLD AIR DAMMING LEADING TO MIXED PCPN INLAND AND MAINLY RAIN AT THE COAST. SHOULD THEN SEE AN EXTENDED PD OF UNSETTLED WX...MAINLY RAIN AS A SLOW MOVING UPPER TROUGH APPROACHES FROM THE WEST. && .AVIATION /17Z MONDAY THROUGH SATURDAY/... COLD FRONT WILL MOVE ACROSS THE TERMINALS THIS AFTERNOON THROUGH EARLY EVENING. MAINLY VFR CONDS...BUT THERE MAY BE SOME BRIEF POCKETS OF MVFR CONDS IN LIGHT RAIN AS THE FRONT MOVES ACROSS THE REGION. WILL ADD SOME -RA TO THE TAFS FROM AROUND 23Z-04Z...BUT WILL KEEP CONDS VFR. S/SW WINDS WILL VEER TO THE W/NW LATE IN THE AFTERNOON...AND THEN WILL VEER TO THE N/NW TONIGHT. WINDS INCREASE TO 10-15 KT WITH 15-20 KT GUSTS DURING THE LATE AFTERNOON/EARLY EVENING...AND THEN GUSTS END BY MIDNIGHT TONIGHT...AND WINDS GRADUALLY DIMINISH TO 8-12 KT THROUGH THE OVERNIGHT. WINDS CONTINUE TO VEER TO THE NE...AND EVENTUALLY TO THE E...ON TUESDAY AT 8-12 KT. ...NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: TIMING OF WIND SHIFT COULD BE OFF BY +/- 1 HOUR. GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA FROM 23Z-04Z. KLGA FCSTER COMMENTS: TIMING OF WIND SHIFT COULD BE OFF BY +/- 1 HOUR. GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA FROM 23Z-04Z. KEWR FCSTER COMMENTS: TIMING OF WIND SHIFT COULD BE OFF BY +/- 1 HOUR. GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA FROM 23Z-04Z. KTEB FCSTER COMMENTS: TIMING OF WIND SHIFT COULD BE OFF BY +/- 1 HOUR. GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA FROM 23Z-04Z. KHPN FCSTER COMMENTS: TIMING OF WIND SHIFT COULD BE OFF BY +/- 1 HOUR. GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA FROM 23Z-04Z. KISP FCSTER COMMENTS: TIMING OF WIND SHIFT COULD BE OFF BY +/- 1 HOUR. GUSTS MAY END PRIOR TO 05Z. LOW CHANCE FOR MVFR CONDS IN -RA FROM 00Z-05Z. .OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY... .TUESDAY...MVFR OR LOW CONDS POSSIBLE LATE AFTERNOON IN -RASN. .TUESDAY NIGHT...WINTRY MIX. RASN ALONG COAST CHANGES TO RAIN EARLY IN THE EVENING. ACROSS INTERIOR...CHANGEOVER WILL BE SLOWER...AS SN MIXES WITH SLEET/FREEZING RAIN BEFORE CHANGING TO FREEZING RAIN. .WEDNESDAY...SUB-VFR POSSIBLE IN -RA/DZ/FG IN THE MORNING. IMPROVING CONDS LATE. .THURSDAY...VFR. .FRIDAY...LIGHT RAIN AND/OR SNOW POSSIBLE IN THE AFTERNOON. .FRIDAY NIGHT...CHANCE FOR RAIN ALONG THE COAST AND SNOW/SLEET/FREEZING RAIN ACROSS INTERIOR. .SATURDAY...CHANCE FOR RAIN ALONG THE COAST AND SNOW/SLEET/FREEZING RAIN FOR INTERIOR IN THE MORNING...THEN CHANCE FOR RAIN IN THE AFTERNOON. && .MARINE... NO CHANGES AT THIS TIME...THOUGH WE MAY NEED SCA ALL WATERS THIS EVENING BEHIND THE COLD FRONT WITH COLD ADVECTION. IT WOULD THOUGH BE SHORT LIVED. SEAS ON THE OCEAN WATERS REMAIN AT SMALL CRAFT LEVELS THIS MORNING IN A SOUTHWEST FLOW AHEAD OF AN APPROACHING COLD FRONT. THEN WITH A WIND SHIFT TO THE NORTHWEST BEHIND THE FRONT...LATE THIS AFTERNOON INTO THIS EVENING...AND COLD ADVECTION WIND GUSTS ON THE OCEAN WATERS WILL BE AT MARGINAL SMALL CRAFT LEVELS. IN ADDITION SEAS WILL STILL BE AT SMALL CRAFT LEVELS AND SLOWLY SUBSIDING. SEAS MAY FALL BELOW SMALL CRAFT LATE TONIGHT INTO EARLY TUESDAY. HOWEVER...WITH A STRONG AND GUSTY NORTHEAST TO EAST FLOW DEVELOPING TUESDAY AS HIGH PRESSURE MOVES THROUGH NEW ENGLAND AND A WAVE OF LOW PRESSURE ON THE COLD FRONT BEGINS TO MOVE NORTH WIND GUSTS WILL AGAIN BE AT SMALL CRAFT LEVELS AND OCEAN SEAS WILL BUILD. WITH HIGH CONFIDENCE IN SMALL CRAFT CONDITIONS HAVE EXTENDED THE ADVISORY THROUGH TUESDAY. EXPECT SCA CONDS ON ALL WATERS TUE NIGHT...WITH MODERATE E FLOW BETWEEN DEPARTING STRONG HIGH PRESSURE AND AN APPROACHING WARM FRONT AND ACCOMPANYING WEAK SFC LOW. GUSTS ON THE OCEAN COULD APPROACH MINIMAL GALE FORCE...ESPECIALLY OUT EAST...AND SEAS COULD BUILDS AS HIGH AS 9 FT. SCA CONDS SHOULD THEN PERSIST ON THE OCEAN INTO WED-WED NIGHT AS THE WARM FRONT LIFTS TO THE N AND MODERATE SW FLOW AHEAD OF A COLD FRONT GUSTS UP TO 25 KT DURING THE DAY ON WED... FOLLOWED BY LINGERING SEAS ABOVE 5 FT WED NIGHT. GENERALLY QUIET CONDS EXPECTED FOR THU-FRI AS HIGH PRESSURE BUILDS IN...BUT OCEAN SEAS COULD APPROACH 5 FT FRI NIGHT AS NE FLOW SOUTH OF THE HIGH INCREASES. && .HYDROLOGY... NO SIGNIFICANT PRECIPITATION IS EXPECTED TODAY THROUGH TUESDAY MORNING. QPF WITH THE WARM FRONTAL APPROACH/PASSAGE FROM LATE DAY TUE INTO WED MORNING SHOULD BE ABOUT 3-4 TENTHS OF AN INCH. SOME OF THIS SHOULD FALL AS SNOW ACROSS INTERIOR LOCATIONS. NO HYDROLOGIC IMPACTS ARE EXPECTED. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST TUESDAY FOR ANZ350-353-355. && $$ SYNOPSIS...TONGUE NEAR TERM...TONGUE SHORT TERM...TONGUE LONG TERM...GOODMAN AVIATION...MPS MARINE...TONGUE HYDROLOGY...TONGUE
AREA FORECAST DISCUSSION
NWS PADUCAH KY
303 PM CST Mon Dec 1 2014 .SHORT TERM...(Tonight through Wednesday night) Issued at 253 PM CST MON DEC 1 2014 The light precipitation activity continues to diminish across the region. Evidence per the RAP and Wvapor imagery of a h7/h5 wave still to our west. It`s rather weak. But there may be just enough lift with the residual moisture, to result in some very light precip through the evening. Both the NAM and RAP pick up on this minimal QPF. The freezing line is expected to move little through the night. So issued a Special Weather Statement for portions of southeast MO, southern IL through the evening, for the potential for spotty very light freezing rain/drizzle. Overnight, PoPs diminish. Dry weather Tuesday through most of Wednesday. Chance of light rain very late in the day working into southeast MO. The chances will increase from SW to NE Wednesday night. Later in the night through early Thursday morning, may see a light mix across northern portions of the area. Temps were a blend of MOS, existing numbers and base model output. .LONG TERM...(Thursday through Sunday) Issued at 303 PM CST MON DEC 1 2014 The GFS/ECMWF ensemble means were in general agreement on the longwave pattern over the CONUS at this time, except on Mon (Day 7) where the picture is a bit murkier in the swrn CONUS. We will be lucky to see the sun in the wrn half of the area on Sat. The finer details of the shrtwv activity were more uncertain among the med range models, as they have had some trouble locking onto the Pacific Express. The extended forecast will start out with the lingering influence of cold high sfc pressure for the PAH forecast area. By 12z Thu, model soundings show the nrn half of the region may receive some light freezing rain, changing to rain by mid morning. Sleet is possible. The srn half will have rain. This should occur as moist flow aloft begins to ride over the cooler air at the sfc. The forecast will be very wet starting Thu night as a frontal boundary sets up west to east somewhere across the PAH forecast area, along with a developing wave of low pressure. The boundary is forecast to move sewd on late on Fri in response to another shrtwv. The best PoPs will be in the srn half of the region. Rain should start to diminish from the nw Fri night as the system moves off, and the region should be rain-free by Sat night under some degree of ridging. The ECMWF and GFS operational 12Z runs have different degrees of mid level ridging over the weekend, and therefore the flatter GFS has yet another shrtwv moving in from the west significantly quicker than the ECMWF/UKMET and possibly the GEM. Therefore, what the initialization blend provided was tamped down a bit as far as the onset of rainfall. At this time, mainly areas west of the MS River will have PoPs Sun. Due to model disagreement, limited chances of rain were left in for Sun night and Mon. For now, thunder was left out of the forecast, though it is not entirely impossible near the low pressure wave Fri. Expect temps to remain relatively mild through the extended period, close to average for this time of year. && .AVIATION... Issued at 1134 AM CST MON DEC 1 2014 Band of precip was from KEVV to KPAH into SEMO, but diminishing from west to east across southern IL into SEMO. Will maintain all liquid -RADZ type wording at KPAH, KEVV and KOWB early this afternoon. Some light freezing precip may persist at KCGI and across portions of southern IL into southeast MO, as a mid level disturbance moves in from the west, and across the region late today and early evening. Some drying working in from the north may allow bases to rise at KEVV and maybe even KCGI. This should transition back to lower cigs tonight as the short range output and assoc Skew-Ts show lowering bases tonight well within MVFR and possibly at or just into IFR late. This is a downward trend from the inherited forecast. Do not have VSBY restrictions in at this time given potential temp/dew point spreads. Will monitor. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ LONG TERM...DB
AREA FORECAST DISCUSSION
NWS PADUCAH KY
253 PM CST Mon Dec 1 2014 .SHORT TERM...(Tonight through Wednesday night) Issued at 253 PM CST MON DEC 1 2014 The light precipitation activity continues to diminish across the region. Evidence per the RAP and Wvapor imagery of a h7/h5 wave still to our west. It`s rather weak. But there may be just enough lift with the residual moisture, to result in some very light precip through the evening. Both the NAM and RAP pick up on this minimal QPF. The freezing line is expected to move little through the night. So issued a Special Weather Statement for portions of southeast MO, southern IL through the evening, for the potential for spotty very light freezing rain/drizzle. Overnight, PoPs diminish. Dry weather Tuesday through most of Wednesday. Chance of light rain very late in the day working into southeast MO. The chances will increase from SW to NE Wednesday night. Later in the night through early Thursday morning, may see a light mix across northern portions of the area. Temps were a blend of MOS, existing numbers and base model output. .LONG TERM...(Thursday through Sunday) Issued at 320 AM CST MON DEC 1 2014 A moist westerly Pacific flow in the upper levels of the atmosphere will keep precip chances in the forecast through most of the long term period. As far as the specific track and timing of systems within this flow, the models are in less agreement than 24 hours ago. Will broad-brush chance pops through the period. As far as the daily details... On Wednesday night, a cold surface high pressure system will be located over the upper Mississippi Valley. The models have trended stronger with this high, which has resulted in lower pops and colder temps over our area. The first in a series of mid-level shortwaves will approach from the west. Any precip that manages to reach the ground could begin as a little freezing rain north of a kcgi/kmdh line. Pops in that area will be only in the slight chance category however. On Thursday and Thursday night, the aforementioned shortwave will produce some rain over portions of the area. The models differ on the track and timing of this shortwave, which seems easiest to locate at the 700 mb level. A relatively warm and moist southwest flow at 850 mb will overrun a cool northeast surface flow. This should contribute to precip coverage. Pops will be kept in the chance category due to model differences in the track of the shortwave. On Friday and Friday night, the models indicate a very moist Pacific shortwave of subtropical origin will track from northern Mexico across the lower and mid Mississippi Valley. The heaviest qpf and best moisture with this system is shown from southern Missouri and southern Kentucky southward. Pops will be in the likely category across se Missouri and sw Kentucky, with chance pops to the north. The 00z ecmwf appears to be an outlier with its stronger surface low passing across northern Arkansas Friday. Will follow the gfs and gefs consensus, which keeps a relatively cool east to southeast surface wind over our region. On Saturday and Saturday night, a short period of mainly dry weather is still expected in the wake of the shortwave passage. The models have shown decent consistency with this drying trend Saturday. However, this will not be the end of the shortwave train as another Pacific system will be waiting in the wings for Sunday or Sunday night. The very persistent surface high over the Great Lakes is forecast to move east, which should allow surface winds to become more southeast to south by late in the weekend. && .AVIATION... Issued at 1134 AM CST MON DEC 1 2014 Band of precip was from KEVV to KPAH into SEMO, but diminishing from west to east across southern IL into SEMO. Will maintain all liquid -RADZ type wording at KPAH, KEVV and KOWB early this afternoon. Some light freezing precip may persist at KCGI and across portions of southern IL into southeast MO, as a mid level disturbance moves in from the west, and across the region late today and early evening. Some drying working in from the north may allow bases to rise at KEVV and maybe even KCGI. This should transition back to lower cigs tonight as the short range output and assoc Skew-Ts show lowering bases tonight well within MVFR and possibly at or just into IFR late. This is a downward trend from the inherited forecast. Do not have VSBY restrictions in at this time given potential temp/dew point spreads. Will monitor. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$
AREA FORECAST DISCUSSION
NWS JACKSON KY
1217 PM EST MON DEC 1 2014 .UPDATE... ISSUED AT 943 AM EST MON DEC 1 2014 A FEW AREAS OF RAIN HAVE BEEN DEVELOPING OVER THE SOUTHERN PART OF THE FORECAST AREA AND OVER NORTHERN TN. AS SUCH HAVE ADDED A SLIGHT CHANCE OF RAIN IN THE SOUTH FOR THIS MORNING TO ACCOUNT FOR THIS. THE MAIN AREA OF RAIN WILL STILL BE SLOW TO REACH THE SOUTHERN PART OF THE FORECAST AREA. NDFD AND ZFP HAVE BEEN UPDATED. UPDATE ISSUED AT 639 AM EST MON DEC 1 2014 THE COLD FRONT IS BASICALLY PERFORMING AS FORECAST STRETCHING FROM LEX TO IOB TO SYM AT THE PRESENT TIME. HOWEVER...THE PROGRESSION OF THE RAIN TO THE SOUTH IS SLIGHTLY SLOWER THAN PREVIOUSLY THOUGHT AND THE LATEST HRRR RUNS ARE REALLY SLOW IN BREAKING OUT RAIN OVER OUR SOUTHEAST COUNTIES. SO...FINE TUNED THE HOURLY POP GRIDS TO SLOW DOWN THE SOUTHWARD PUSH A FEW HOURS. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 316 AM EST MON DEC 1 2014 THE COLD FRONT IS ON OUR DOORSTEP AT 3 AM HAVING JUST NOW PASSED THE MAYSVILLE MESONET STATION. THIS WILL PROGRESS STEADILY THROUGH OUR AREA THIS MORNING EXITING INTO VIRGINIA BY LATE AFTERNOON. RAIN SHOWERS CONTINUE TO BLOSSOM ALONG AND BEHIND THE FRONT. THESE WILL PROGRESS SLOWLY SOUTHEAST INTO OUR NORTHERN COUNTIES OVER THE NEXT FEW HOURS. THE RAIN MAY DIMINISH SOME LATER IN THE MORNING AS IT WORKS INTO THE HEART OF EAST KENTUCKY...BUT AN UPSTREAM SHORTWAVE SHOULD CAUSE IT TO EXPAND AGAIN LATE IN THE DAY AND INTO THE EVENING HOURS. THE OTHER IMPACTS BROUGHT BY THE PASSAGE OF THE FRONT WILL BE A QUICK SHIFT IN WINDS TO THE NORTHWEST...AND FALLING TEMPS. EARLY HIGHS AROUND 60 WILL END UP RANGING FROM THE UPPER 30S ALONG I-64 TO THE UPPER 40S ALONG THE VIRGINIA BORDER BY EARLY EVENING. THE OTHER CONCERN HAS BEEN THE THREAT FOR A BIT OF WINTRY PRECIP TONIGHT NORTH OF I-64. WHILE WE CANNOT RULE OUT A LITTLE INCONSEQUENTIAL SLEET DURING THE EVENING...WE DID NOT MENTION THIS IN THE FORECAST. WE DID KEEP A SLIGHT CHANCE OF FREEZING RAIN IN THE FORECAST NORTH OF I-64 LATE IN THE NIGHT AND EARLY TUESDAY MORNING AS THERE MAY BE A FEW POCKETS DROP TO FREEZING THERE. IF THE FREEZING PRECIP DOES OCCUR...ROAD TEMPS WOULD LIKELY NOT GET COLD ENOUGH FOR ANY WORRIES. ON TUESDAY...THE 850 MB FLOW RAMPS UP OVER THE STATE AND BACKS TO THE SOUTHWEST IN RESPONSE TO A SHORTWAVE DIVING INTO THE NORTHERN PLAINS. THIS WILL BEGIN TO PUSH THE SURFACE BOUNDARY BACK TO THE NORTH WITH TEMPERATURES OVER OUR SOUTHEAST COUNTIES WARMING WELL INTO THE 50S...WHILE OUR NORTHERN COUNTIES STRUGGLE TO REACH THE 40S. A LITTLE OVERRUNNING LIGHT RAIN AND DRIZZLE CAN BE EXPECTED THROUGHOUT THE DAY AS WELL. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 316 AM EST MON DEC 1 2014 ACTIVE WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE WEEK AND INTO THE UPCOMING WEEKEND. WHILE DIFFERENCES ARE EVIDENT IN THE MODELS...ONE THING THEY DO AGREE ON IS KEEPING A STALLED BOUNDARY ACROSS THE AREA INTO THURSDAY...AND KEEPING THE WEATHER UNSETTLED INTO SATURDAY. THIS WILL KEEP A FAIRLY GOOD TEMPERATURE/DEWPOINT GRADIENT ACROSS THE AREA FOR SEVERAL DAYS. THUS...TEMPERATURE FORECAST IS HIGHLY DEPENDENT WHERE THAT FRONT IS AT ANYTIME BETWEEN NOW AND THE WEEKEND AND WILL FEATURE PLENTY OF ROOM FOR TEMPERATURE TO GO UP OR DOWN FROM THE CURRENT FORECAST. IN THIS SCENARIO...A BLENDED FORECAST IS CERTAINLY A GOOD WAY TO GO...AND STAY AWAY FROM THE EXTREME HIGHS AND LOWS FOR NOW. CLOUD COVER WILL HANG TOUGH RIGHT THROUGH THE END OF THE WEEK WHICH WILL ALSO LIMIT THE DIURNAL RANGE IN TEMPERATURES. AS FAR AS RAIN CHANCES GO...WE MAY SEE SOME LIGHT RAIN/DRIZZLE HOLD ON THROUGH TUESDAY NIGHT INTO WEDNESDAY...ESPECIALLY ACROSS SOUTHEAST KENTUCKY. A BRIEF PERIOD OF SUBSIDENCE MAY SHALLOW OUT THE MOISTURE ENOUGH TO CUT OFF THE RAIN POTENTIAL FROM MIDDAY WEDNESDAY INTO WEDNESDAY NIGHT. HOWEVER...A MID LEVEL SHORTWAVE WILL PUSH EAST ON THURSDAY...BRINGING THE THREAT OF RAIN BACK INTO THE AREA. AT THIS POINT...MODELS DIFFER QUITE A BIT ON HOW THINGS PLAY OUT INTO THE UPCOMING WEEKEND...BUT REGARDLESS OF WHICH MODEL YOU BUY INTO... IT WILL REMAIN DAMP WITH RAIN CHANCES CONTINUING INTO SATURDAY. IT DOES LOOKS LIKE SOME POTENTIAL FOR US TO DRY OUT BY THE SECOND HALF OF THE WEEKEND...SO WILL TREND POPS DOWNWARD BY THE END OF THE PERIOD. AT THIS TIME...WHILE IT DOES LOOK DAMP INTO NEXT WEEKEND... PRECIPITATION AMOUNTS SHOULD REMAIN OVERALL FAIRLY LIGHT THROUGH THE PERIOD...WITH NO BIG SURGES OF HEAVY RAINFALL. THUS...IT DOES NOT LOOK LIKE WE SHOULD HAVE MUCH FLOODING CONCERNS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1217 PM EST MON DEC 1 2014 AT 1715Z A COLD FRONT EXTENDS FROM JUST SOUTH OF SME TO JUST NORTH OF LOZ TO JUST SOUTH OF JKL TO NEAR SJS. THE FRONT WILL BE SOUTH OF ALL THE TAF SITES BY 18Z. AHEAD OF THE FRONT MVFR CEILINGS PREVAIL...WHILE ON THE NORTH SIDE OF THE FRONT IFR CEILINGS ARE THE RULE. THE FRONT WILL CONTINUE TO PRESS SOUTH AND MOVE OUT OF KENTUCKY AND INTO TN AND VA BY EVENING. SOME AREAS OF LIGHT RAIN WILL OCCUR ALONG AND AHEAD OF THE FRONT...BUT MOST OF THE RAIN IS WELL NORTH OF THE FRONT...AND THIS WILL CONTINUE TO BE CASE THIS AFTERNOON AND TONIGHT. AS THE FRONT SAGS FURTHER SOUTH CEILINGS WILL LOWER AND WINDS WILL GRADUALLY GO FROM NORTH TO NORTHEAST. IFR CONDITIONS IN LIGHT RAIN...WITH FOG AND LOW CEILINGS WILL PREVAIL TONIGHT. IFR CEILINGS WILL PERSIST INTO THE DAY ON TUESDAY. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SBH SHORT TERM...ABE LONG TERM...KAS AVIATION...SBH
AREA FORECAST DISCUSSION
NWS CARIBOU ME
542 PM EST MON DEC 1 2014 .SYNOPSIS... STRONG CANADIAN HIGH PRESSURE WILL APPROACH FROM THE WEST TONIGHT AND WILL CROSS THE REGION TUESDAY. A WARM FRONT WILL APPROACH FROM THE SOUTHWEST LATE TUESDAY NIGHT AND CROSS THE REGION BY LATE WEDNESDAY. A NEW COLD FRONT WILL CROSS THE REGION THURSDAY. && .NEAR TERM /THROUGH TUESDAY NIGHT/... 535 PM UPDATE...SATELLITE IR IMAGERY SHOWING A PLUME SETTING UP OFF THE OPEN ST. LAWRENCE W/AN UPPER LEVEL DISTURBANCE MOVING INTO THE REGION. THIS FEATURE IS PICKED UP WELL ON THE WATER VAPOR IMAGERY AND BY THE LATEST RUN OF THE RAP MODEL. METARS AND WEBCAMS SHOWING SOME LIGHT SNOW ACROSS NORTHERN MAINE INCLUDING THE ST. JOHN VALLEY. THE DAYCREW DID A GOOD JOB IN PICKING THIS UP THROUGH THIS EVENING. THE ONLY ADJUSTMENTS WAS TO MOVE AREA OF SNOW FURTHER S TOWARD THE HOULTON REGION. A DUSTING OF SNOW IS EXPECTED. HRLY TEMPERATURES NEEDED SOME ADJUSTMENT TO MATCH UP W/THE LATEST OBS. SKIES SHOULD CLR BY SUNRISE TUE FOR MOST LCTNS. WITH BRISK NW WINDS...TEMPS OVRNGT AND ON TUE WILL BE MUCH COLDER...SPCLY CNTRL AND DOWNEAST AREAS. UNDER MSLY SUNNY SKIES AND DECREASING WINDS... HI TEMPS TUE WILL BE IN THE TEENS N TO LOWER TO MID 20S DOWNEAST... ABOUT 20 TO 30 DEG LOWER THAN TDY. WINDS WILL DECREASE TUE AFTN AS THE SFC HI AXIS CRESTS THE REGION. TUE EVE WILL BEGIN MCLR TO PTLY CLDY...ALLOWING FOR SOME RADIATIONAL COOLING...BUT TEMPS WILL LVL OUT TO ERLY LOWS BY OVRNGT AS HI THIN CS CLD CVR THICKENS WITH THE APCH OF THE SFC LOW AND ASSOCIATED S/WV ALF FROM THE GREAT LKS BEGINS TO APCH THE REGION. OVRRNG PRECIP...MSLY INITIALLY IN THE FORM OF LGT SN...BEGINS TO MOVE INTO THE REGION FROM WSW TO ENE LATE TUE NGT AS DEEP LOW TO MID LVL S TO SE WINDS INCREASE. THIS WILL RESULT IN SIG RISES IN TEMPS ACROSS THE REGION BY DAYBREAK WED...WITH 1 TO 2 INCHES OF SNFL ACROSS THE REGION BY THIS TM. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... EXPECT OVERRUNNING PRECIPITATION TO BE ONGOING JUST ABOUT ACROSS THE ENTIRE FORECAST AREA BY WEDNESDAY MORNING. WINTER WEATHER ADVISORIES WILL BE NEEDED FOR MUCH OF THE REGION INTO WEDNESDAY AS WARMER AIR ADVECTING IN ALOFT RESULTS IN A PERIOD OF MIXED PRECIPITATION AND FREEZING RAIN JUST INLAND FROM THE IMMEDIATE COAST. THE LOW LEVELS ARE EXPECTED TO WARM DURING WEDNESDAY WITH MIXED PRECIPITATION AND FREEZING RAIN TRANSITIONING TO ALL RAIN FROM SOUTH TO NORTH ACROSS MOST OF THE AREA BY WEDNESDAY AFTERNOON. THE ONLY EXCEPTION WILL BE THE ST JOHN VALLEY WHERE FREEZING PRECIPITATION MAY LINGER WELL INTO THE AFTERNOON HOURS. A COLD FRONT WILL SWEEP ACROSS THE REGION WEDNESDAY EVENING WITH THE CHANCE FOR SNOW SHOWERS PARTICULARLY ACROSS NORTHERN AND CENTRAL AREAS WHERE WE COULD SEE AN INCH OR SO OF SNOW ACCUMULATION. THURSDAY WILL TURN COLDER WITH A FEW SNOW SHOWERS POSSIBLE THURSDAY MORNING ACROSS NORTHERN AREAS OTHERWISE IT WILL BE DRY. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... HIGH PRESSURE WILL BUILD OVER THE AREA THURSDAY NIGHT WITH CLEAR AND VERY COLD CONDITIONS EXPECTED. LOWS THURSDAY NIGHT WILL FALL TO AROUND ZERO WITH SOME SUB ZERO READINGS LIKELY IN THE NORMALLY COLDER SHELTERED VALLEY LOCATIONS. FRIDAY WILL BE CONTINUED COLD AND DRY AS HIGH PRESSURE SLIDES TO OUR EAST. THE FORECAST FOR THE WEEKEND NOT QUITE CUT AND DRY AT THIS POINT WITH DIFFERENCES IN MODEL SOLUTIONS. GFS SOLUTION SUGGESTS A COLD AND DRY WEEKEND AS IT BUILDS HIGH PRESSURE ACROSS TO OUR NORTH. THE ECMWF BRINGS A FRONT INTO THE AREA DURING SATURDAY WITH THE CHANCE OF PRECIPITATION. STAYED WITH THE SUPERBLEND GUIDANCE WHICH BRINGS LOW CHANCE OF PRECIPITATION SATURDAY AND SUNDAY. HIGH PRESSURE WILL START TO BUILD BACK IN BY MONDAY. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... NEAR TERM: A WINTRY MIX OF PRECIPITATION CAN BE EXPECTED AT THE TERMINALS WEDNESDAY MORNING WITH THE EXCEPTION OF KBHB WHERE WE SHOULD SEE ALL RAIN BY 12Z. THE FREEZING/FROZEN PRECIPITATION SHOULD TRANSITION TO ALL RAIN ACROSS THE TERMINALS FROM SOUTH TO NORTH DURING WEDNESDAY AFTERNOON WITH WIDESPREAD IFR/MVFR EXPECTED ALL TERMINALS. MVFR CAN BE EXPECTED WEDNESDAY NIGHT IN NORTHERN SHOW SHOWERS AND RAIN SHOWERS CHANGING TO SNOW SHOWERS. VFR EXPECTED THURSDAY AND FRIDAY. VFR OR MVFR CONDITIONS LIKELY SATURDAY. SHORT TERM: MSLY VFR DOWNEAST SITES AND MVFR OR LOW VFR CLGS IN BKN-OVC SC FOR NRN TAF SITES INTO THE OVRNGT...WITH BRIEF IFR VSBYS POSSIBLE IN ISOLD SN SHWRS FOR NRN TAF SITES. ALL TAF SITES THEN BECOME VFR BY DAYBREAK TUE AND CONT SO THRU TUE EVE. THEN CLGS AND VSBYS LOWER WSW TO ENE WITH THE ARRIVAL OF LGT SN LATE TUE NGT...XCPT LGT SN OR MIXED PRECIP FOR KBHB. && .MARINE... NEAR TERM: WILL CONT THE CURRENT SCA TNGT FOR MSLY WIND OVR THE INNER BAY/HARBOR MZ052 AND FOR BOTH WINDS AND SEAS FOR OUTER MZS050-051. AFTWRDS...WINDS AND SEAS SHOULD SUBSIDE BLO SCA CRITERIA LATER TUE MORN AND CONT SO THRU TUE EVE. WINDS AND SEAS BUILD BACK TO SCA OVR ALL OF OUR WATERS BY WED MORN AS SE WINDS INCREASE ARND DEPARTING SFC HI PRES MOVG E OF THE CAN MARITIMES. SHORT TERM: EXPECT SMALL CRAFT ADVISORY CONDITIONS WEDNESDAY THROUGH THURSDAY. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST TUESDAY FOR ANZ050>052. && $$ NEAR TERM...HEWITT/VJN SHORT TERM...DUDA LONG TERM...DUDA AVIATION...HEWITT/VJN/DUDA MARINE...HEWITT/VJN/DUDA
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
221 PM EST MON DEC 1 2014 .SYNOPSIS... AN ACTIVE WEATHER PATTERN WILL REMAIN IN PLACE THE FIRST PART OF THE WORK WEEK BEFORE HIGH PRESSURE SERVES UP A QUIET THURSDAY. YET ANOTHER WEATHER SYSTEM TAKES AIM AT OUR REGION FRIDAY INTO SATURDAY WITH THE POTENTIAL FOR A WINTRY MIX. && .NEAR TERM /THROUGH TONIGHT/... COLDER AIR ALOFT HAS MOVED INTO PARTS OF THE REGION AS DENOTED BY LATEST RAP ANALYSIS WITH H8 TEMPS RANGING FROM 0C TO -4C N OF I-70 AS OF 18Z. WSR-88D KPBZ IS PICKING UP SLEET / LARGE SNOWFLAKE MIXTURE NICELY IN THE DUAL POL CORRELATION COEFFICIENT FIELD AS VALUES RANGE BETWEEN 0.9 AND 0.95. PRECIPITATION WILL END LATE THIS AFTERNOON WITH LOCATIONS SOUTH OF THE MASON DIXON LINE BECOMING DRY TOWARD MIDNIGHT GIVEN LINEAR EXTRAPOLATION OF RAIN OVER SOUTHWESTERN OHIO...HOWEVER THAT BREAK WILL BE VERY BRIEF BEFORE NEXT SYSTEM TAKES AIM. AS HIGH PRESSURE PASSES TO OUR NORTH PLENTY OF MID AND UPPER LEVEL MOISTURE RESIDES PREVENTING STRONG RADIATIONAL COOLING DESPITE DEWPOINTS DROPPING BACK WELL INTO THE TEENS. OPTED FOR A WARMER GUIDANCE SUITE KEEPING LOWER TO MID 20S OVER FAR NORTHERN SECTIONS /NORTH OF I-80/. WHERE CLOUDS AND PRECIP LAST LONGER IN THE SOUTHERN PART OF THE FORECAST AREA...LOWS WILL FALL BACK TO AROUND 30. CARRIED A WINTRY MIX OF SNOW AND SLEET WHERE POPS REMAIN THIS EVENING. DO NOT SEE I-68 CORRIDOR GOING TO A WINTRY MIX UNTIL AROUND 22Z-0Z GIVEN W TO E ORIENTATION OF THERMAL GRADIENT. && .SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/... LATEST 12Z OPERATIONAL NCEP RUNS CONTINUE THEME OF PREVIOUS DAY SOLUTIONS ALONG WITH OFFSETTED HOURS OF SREF AND THEIR RESPECTIVE ENSEMBLES OF A WINTRY MIX TUESDAY INTO WEDNESDAY MORNING. QPF VALUES HAVE TRENDED NORTHWARD...HOWEVER LOOKING AT CROSS SECTIONS OF UVV...MOISTURE...AND STABILITY HARD TO SEE THAT MUCH QPF OVER GARRETT AND TUCKER. RECENT EVENTS AND THEIR HIGH BIAS ALSO SUPPORTS LOWER LIQUID AMOUNTS THAN PROJECTED. AS COLD AIR INFILTRATES THE REGION TONIGHT AND TRANSITORY SURFACE ANTICYCLONE MOVES TO NEW ENGLAND...WARM LAYER ALOFT DEVELOPS IN A COLD AIR DAMMING SETUP. AS ELUDED TOO IN MY PREVIOUS DISCUSSIONS...AGEOSTROPHIC FLOW IS NOT THAT STRONG...HENCE ONLY A 40 KNOT BARRIER JET ALONG THE APPALACHIANS. IN SIGNIFICANT ICING EVENTS...THIS FLOW WOULD BE NEARLY A FACTOR OF TWO HIGHER. INHERITED FORECAST COVERS THIS AREA WELL WITH TIMING AND PCPN CHANGE OVER. ALL LOCATIONS IN THE EASTERN PERIPHERY OF THE CWA COULD SEE A PERIOD OF SNOW AND/OR SLEET AT THE ONSET BEFORE A SWITCH OVER TO FZRA. BUFR SOUNDINGS SHOW MAX WARM LAYER ALOFT TEMPERATURES CLIMBING BETWEEN 1C AND 3C ACROSS EASTERN PA ZONES AND WITH OVERNIGHT TEMPS FALLING BACK WELL INTO THE 20S...A PERIOD OF FZRA IS PREDICTED FROM FOREST CO SOUTH INTO EASTERN FAYETTE COUNTY. HOISTED A FREEZING RAIN ADVISORY IN COLLABORATION WITH WFO STATE COLLEGE TUESDAY MORNING THROUGH DAYBREAK WEDNESDAY. ELECTED TO END ADVISORY FOR EASTERN WESTMORELAND AND FAYETTE COUNTIES TUESDAY NIGHT GIVEN BL FLOW SHOULD ERADICATE COLD AIR AT THE SFC EVEN ACROSS THE DEEPER VALLEYS BETWEEN CHESTNUT AND LAUREL RIDGES. FARTHER NORTH...CONFIDENCE IS HIGHER FOR COLD AIR TO STAY LOCKED IN PLACE...WHICH FOLLOWS CLIMATOLOGICAL NORM. CLARION COUNTY WAS THROWN IN...HOWEVER THEY SHOULD SWITCH OVER TO RAIN A FEW HOURS SOONER THAN THEIR COUNTERPARTS TO THE NORTH /FOREST/ AND EAST /JEFFERSON/. ONE POSITIVE THING HEADING INTO THIS EVENT IS GIVEN THE RECENT WARM WEATHER...THE GROUND WILL NOT BE AS COLD AS IT WAS FOR THE ICING EVENT IN MID NOVEMBER. WE STILL DO NOT EXPECT A SIGNIFICANT ICE STORM FOR ANY OF OUR COUNTIES. IF THE SOUTHEAST WINDS ARE STRONG THAN EXPECTED...IT IS POSSIBLE THE GARRETT AND TUCKER COULD SEE IN EXCESS OF A QUARTER OF AN INCH...BUT AFTER REVIEW OF PLUME DIAGRAMS FOR 2G4 AND PIE SIDED WITH THE MEAN OF THE PAST FEW RUNS WHICH PLACES STORM TOTAL ICE ACCUMULATION AROUND 0.15 TO 0.20 INCHES. A QUARTER OF AN INCH OF ICE IS NEEDED FOR AN ICE STORM WARNING. TEMPERATURES WERE A BLEND OF THE ONGOING FORECAST AND THE ADJMET BIAS CORRECTED GRIDS. A GRADUAL WARM UP TO SEASONAL NUMBER IN THE LOWER TO MID 40S IS SLATED FOR MID WEEK. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... MOISTURE ERODES FROM THE TOP DOWN WEDS AS SFC HIGH PRESSURE TRIES TO NOSE IN FROM THE WEST. MOISTURE TRAPPED UNDER THE H85 INVERSION WILL KEEP POP CHCS IN THROUGH EARLY THURS...BUT MAY OCCUR MORE IN THE FORM OF LIGHT DRIZZLE THAN ANYTHING ELSE. MOISTURE IS FINALLY SCOURED OUT COMPLETELY THURS FOR WHAT SHOULD BE THE DRIEST DAY OF THE WORK WEEK BEFORE THE NEXT SYSTEM BEGINS TO ENCROACH FROM THE SOUTH. A BOUNDARY WILL ONCE AGAIN SET UP NEAR OR JUST SOUTH OF THE AREA EARLY FRI...WITH WEAK WAVES MOVING ALONG IT. COLD AIR IN PLACE AHEAD OF THE MOISTURE COULD RESULT IN ANOTHER ROUND OF WINTRY MIX AND POSSIBLY SOME FREEZING RAIN. WITH THIS BEING DAY 4...TRIED TO KEEP DETAILS GENERAL...AND WILL NEED FURTHER ROUNDS OF MODEL DATA TO HASH OUT THE FINER DETAILS. ATTM...ECMWF IS FURTHER NORTH...RESULTING IN THE WETTER SOLN WHILE THE GFS PASSES THE MAIN LOW SOUTH FRI NIGHT. SFC HIGH PRESSURE TRIES TO BUILD BACK IN FOR THE END OF THE WEEKEND. TAX && .AVIATION /19Z MONDAY THROUGH SATURDAY/... ANOTHER WAVE PASSING ALONG THE COLD FRONT IS GENERATING SOME MVFR/IFR SHOWERS THROUGH MUCH OF THE AREA...BUT SHOULD PASS TO THE EAST BY 20Z-22Z. DRYING IN THE MID-LEVELS SHOULD RESULT IN A SPELL OF VFR THIS EVENING AND TONIGHT WITH HIGH CLOUDS LINGERING. THE NEXT WAVE PUSHES SOUTH TO NORTH TUES MORNING SPREADING MVFR/IFR CIGS ALONG WITH RAIN AND IN SOME OF THE ERN AND NRN TERMINALS A WINTRY MIX. COLD TEMPERATURES INVADING THE AREA CURRENTLY WILL SET-UP FZRA POTENTIAL FOR MGW-LBE-DUJ. ATTM...HANDLED FZRA WITH PROB30 GROUPS...AS SOME UNCERTAINTY STILL EXISTS. PRECIPITATION SHOULD BE CONFINED TO THE ERN 2/3 OF THE CWA...BUT MVFR/IFR CIGS SHOULD BE PREVALENT THROUGH TUES. OUTLOOK.../TUESDAY THROUGH FRIDAY/... MVFR RESTRICTIONS ARE LIKELY TO CONTINUE BEFORE A COLD FRONT PASSES WEDS NIGHT. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 11 PM EST TUESDAY FOR MDZ001. OH...NONE. PA...FREEZING RAIN ADVISORY FROM 7 AM TUESDAY TO 7 AM EST WEDNESDAY FOR PAZ009-015-016-023. FREEZING RAIN ADVISORY FROM 7 AM TO 9 PM EST TUESDAY FOR PAZ074-076. WV...FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 11 PM EST TUESDAY FOR WVZ023-041. && $$ SYNOPSIS...98 NEAR TERM...98 SHORT TERM...98 LONG TERM...TAX AVIATION...TAX
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
101 PM EST MON DEC 1 2014 .SYNOPSIS... AN ACTIVE WEATHER PATTERN WILL REMAIN IN PLACE THE FIRST PART OF THE WORK WEEK BEFORE HIGH PRESSURE SERVES UP A QUIET THURSDAY. YET ANOTHER WEATHER SYSTEM TAKES AIM AT OUR REGION FRIDAY INTO SATURDAY WITH THE POTENTIAL FOR A WINTRY MIX. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... BAROCLINIC ZONE IS THROUGH MOST OF THE CWA AS OF 16Z...HOWEVER MID LEVEL POCKET OF INSTABILITY IS TRAVERSING ALONG THE COOL SIDE OF THE BOUNDARY. BROUGHT LKLY AND CAT POPS TO THE I-76 CORRIDOR THROUGH THE EARLY AFTERNOON AS BATCH OF RAIN MOVES THROUGH. STILL CARRY HIGH POPS SOUTH OF THE MASON DIXON LINE INTO THE EVENING HOURS. IT WILL BE RACE IF THE COLD AIR JUST ABOVE THE SURFACE CAN CATCH UP CREATING A PERIOD OF SNOW AND SLEET AT THE VERY END. FOR NOW...OPTED TO KEEP A WINTRY MIX THIS IN PLACE ACROSS EASTERN OHIO BASED LATEST HRRR SIMULATED REFLECTIVITY AND PTYPE ALGORITHM. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/... LATEST 12Z OPERATIONAL NCEP RUNS CONTINUE THEME OF PREVIOUS DAY SOLUTIONS ALONG WITH OFFSETTED HOURS OF SREF AND THEIR RESPECTIVE ENSEMBLES OF A WINTRY MIX TUESDAY INTO WEDNESDAY MORNING. QPF VALUES HAVE TRENDED NORTHWARD...HOWEVER LOOKING AT CROSS SECTIONS OF UVV...MOISTURE...AND STABILITY HARD TO SEE THAT MUCH QPF OVER GARRETT AND TUCKER. RECENT EVENTS AND THEIR HIGH BIAS ALSO SUPPORTS LOWER LIQUID AMOUNTS THAN PROJECTED. AS COLD AIR INFILTRATES THE REGION TONIGHT AND TRANSITORY SURFACE ANTICYCLONE MOVES TO NEW ENGLAND...WARM LAYER ALOFT DEVELOPS IN A COLD AIR DAMMING SETUP. AS ELUDED TOO IN MY PREVIOUS DISCUSSIONS...AGEOSTROPHIC FLOW IS NOT THAT STRONG...HENCE ONLY A 40 KNOT BARRIER JET ALONG THE APPALACHIANS. IN SIGNIFICANT ICING EVENTS...THIS FLOW WOULD BE NEARLY A FACTOR OF TWO HIGHER. INHERITED FORECAST COVERS THIS AREA WELL WITH TIMING AND PCPN CHANGE OVER. ALL LOCATIONS IN THE EASTERN PERIPHERY OF THE CWA COULD SEE A PERIOD OF SNOW AND/OR SLEET AT THE ONSET BEFORE A SWITCH OVER TO FZRA. BUFR SOUNDINGS SHOW MAX WARM LAYER ALOFT TEMPERATURES CLIMBING BETWEEN 1C AND 3C ACROSS EASTERN PA ZONES AND WITH OVERNIGHT TEMPS FALLING BACK WELL INTO THE 20S...A PERIOD OF FZRA IS PREDICTED FROM FOREST CO SOUTH INTO EASTERN FAYETTE COUNTY. HOISTED A FREEZING RAIN ADVISORY IN COLLABORATION WITH WFO STATE COLLEGE TUESDAY MORNING THROUGH DAYBREAK WEDNESDAY. ELECTED TO END ADVISORY FOR EASTERN WESTMORELAND AND FAYETTE COUNTIES TUESDAY NIGHT GIVEN BL FLOW SHOULD ERADICATE COLD AIR AT THE SFC EVEN ACROSS THE DEEPER VALLEYS BETWEEN CHESTNUT AND LAUREL RIDGES. FARTHER NORTH...CONFIDENCE IS HIGHER FOR COLD AIR TO STAY LOCKED IN PLACE...WHICH FOLLOWS CLIMOTOLOGICAL NORM. CLARION COUNTY WAS THROWN IN...HOWEVER THEY SHOULD SWITCH OVER TO RAIN A FEW HOURS SOONER THAN THEIR COUNTERPARTS TO THE NORTH /FOREST/ AND EAST /JEFFERSON/. ONE POSITIVE THING HEADING INTO THIS EVENT IS GIVEN THE RECENT WARM WEATHER...THE GROUND WILL NOT BE AS COLD AS IT WAS FOR THE ICING EVENT IN MID NOVEMBER. WE STILL DO NOT EXPECT A SIGNIFICANT ICE STORM FOR ANY OF OUR COUNTIES. IF THE SOUTHEAST WINDS ARE STRONG THAN EXPECTED...IT IS POSSIBLE THE GARRETT AND TUCKER COULD SEE IN EXCESS OF A QUARTER OF AN INCH...BUT AFTER REVIEW OF PLUME DIAGRAMS FOR 2G4 AND PIE SIDED WITH THE MEAN OF THE PAST FEW RUNS WHICH PLACES STORM TOTAL ICE ACCUMULATION AROUND 0.15 TO 0.20 INCHES. A QUARTER OF AN INCH OF ICE IS NEEDED FOR AN ICE STORM WARNING. TEMPERATURES WERE A BLEND OF THE ONGOING FORECAST AND THE ADJMET BIAS CORRECTED GRIDS. A GRADUAL WARM UP TO SEASONAL NUMBER IN THE LOWER TO MID 40S IS SLATED FOR MID WEEK. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... SYSTEM DEVELOPING ACROSS THE CENTRAL PLAINS WILL PUSH NORTHEAST INTO THE REGION THURSDAY NIGHT INTO FRIDAY. HAVE KEPT POPS IN THE FORECAST LONGER WITH THE FRONT...AS PRECIPITATION MAY NOW LINGER INTO SATURDAY AND POSSIBLY EVEN SATURDAY NIGHT IF THE 00Z ECMWF SOLUTION IS CORRECT. COULD POSSIBLY SEE MIXED PRECIPITATION EACH NIGHT DEPENDING ON TEMPERATURES. RIDGE OF HIGH PRESSURE BUILDS IN BY SUNDAY...ALLOWING FOR A RETURN TO DRY WEATHER. TEMPERATURES WILL BE SEASONABLE THROUGH THE PERIOD. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... ANOTHER WAVE PASSING ALONG THE COLD FRONT IS GENERATING SOME MVFR/IFR SHOWERS THROUGH MUCH OF THE AREA...BUT SHOULD PASS TO THE EAST BY 20Z-22Z. DRYING IN THE MID-LEVELS SHOULD RESULT IN A SPELL OF VFR THIS EVENING AND TONIGHT WITH HIGH CLOUDS LINGERING. THE NEXT WAVE PUSHES SOUTH TO NORTH TUES MORNING SPREADING MVFR/IFR CIGS ALONG WITH RAIN AND IN SOME OF THE ERN AND NRN TERMINALS A WINTRY MIX. COLD TEMPERATURES INVADING THE AREA CURRENTLY WILL SET-UP FZRA POTENTIAL FOR MGW-LBE-DUJ. ATTM...HANDLED FZRA WITH PROB30 GROUPS...AS SOME UNCERTAINTY STILL EXISTS. PRECIPITATION SHOULD BE CONFINED TO THE ERN 2/3 OF THE CWA...BUT MVFR/IFR CIGS SHOULD BE PREVALENT THROUGH TUES. OUTLOOK.../TUESDAY THROUGH FRIDAY/... MVFR RESTRICTIONS ARE LIKELY TO CONTINUE BEFORE A COLD FRONT PASSES WEDS NIGHT. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 11 PM EST TUESDAY FOR MDZ001. OH...NONE. PA...FREEZING RAIN ADVISORY FROM 7 AM TUESDAY TO 7 AM EST WEDNESDAY FOR PAZ009-015-016-023. FREEZING RAIN ADVISORY FROM 7 AM TO 9 PM EST TUESDAY FOR PAZ074-076. WV...FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 11 PM EST TUESDAY FOR WVZ023-041. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1146 AM EST MON DEC 1 2014 .SYNOPSIS... AN ACTIVE WEATHER PATTERN WILL REMAIN IN PLACE THE FIRST PART OF THE WORK WEEK BEFORE HIGH PRESSURE SERVES UP A QUIET THURSDAY. YET ANOTHER WEATHER SYSTEM TAKES AIM AT OUR REGION FRIDAY INTO SATURDAY WITH THE POTENTIAL FOR A WINTRY MIX. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... BAROCLINIC ZONE IS THROUGH MOST OF THE CWA AS OF 16Z...HOWEVER MID LEVEL POCKET OF INSTABILITY IS TRAVERSING ALONG THE COOL SIDE OF THE BOUNDARY. BROUGHT LKLY AND CAT POPS TO THE I-76 CORRIDOR THROUGH THE EARLY AFTERNOON AS BATCH OF RAIN MOVES THROUGH. STILL CARRY HIGH POPS SOUTH OF THE MASON DIXON LINE INTO THE EVENING HOURS. IT WILL BE RACE IF THE COLD AIR JUST ABOVE THE SURFACE CAN CATCH UP CREATING A PERIOD OF SNOW AND SLEET AT THE VERY END. FOR NOW...OPTED TO KEEP A WINTRY MIX THIS IN PLACE ACROSS EASTERN OHIO BASED LATEST HRRR SIMULATED REFLECTIVITY AND PTYPE ALGORITHM. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/... LATEST 12Z OPERATIONAL NCEP RUNS CONTINUE THEME OF PREVIOUS DAY SOLUTIONS ALONG WITH OFFSETTED HOURS OF SREF AND THEIR RESPECTIVE ENSEMBLES OF A WINTRY MIX TUESDAY INTO WEDNESDAY MORNING. QPF VALUES HAVE TRENDED NORTHWARD...HOWEVER LOOKING AT CROSS SECTIONS OF UVV...MOISTURE...AND STABILITY HARD TO SEE THAT MUCH QPF OVER GARRETT AND TUCKER. RECENT EVENTS AND THEIR HIGH BIAS ALSO SUPPORTS LOWER LIQUID AMOUNTS THAN PROJECTED. AS COLD AIR INFILTRATES THE REGION TONIGHT AND TRANSITORY SURFACE ANTICYCLONE MOVES TO NEW ENGLAND...WARM LAYER ALOFT DEVELOPS IN A COLD AIR DAMMING SETUP. AS ELUDED TOO IN MY PREVIOUS DISCUSSIONS...AGEOSTROPHIC FLOW IS NOT THAT STRONG...HENCE ONLY A 40 KNOT BARRIER JET ALONG THE APPALACHIANS. IN SIGNIFICANT ICING EVENTS...THIS FLOW WOULD BE NEARLY A FACTOR OF TWO HIGHER. INHERITED FORECAST COVERS THIS AREA WELL WITH TIMING AND PCPN CHANGE OVER. ALL LOCATIONS IN THE EASTERN PERIPHERY OF THE CWA COULD SEE A PERIOD OF SNOW AND/OR SLEET AT THE ONSET BEFORE A SWITCH OVER TO FZRA. BUFR SOUNDINGS SHOW MAX WARM LAYER ALOFT TEMPERATURES CLIMBING BETWEEN 1C AND 3C ACROSS EASTERN PA ZONES AND WITH OVERNIGHT TEMPS FALLING BACK WELL INTO THE 20S...A PERIOD OF FZRA IS PREDICTED FROM FOREST CO SOUTH INTO EASTERN FAYETTE COUNTY. HOISTED A FREEZING RAIN ADVISORY IN COLLABORATION WITH WFO STATE COLLEGE TUESDAY MORNING THROUGH DAYBREAK WEDNESDAY. ELECTED TO END ADVISORY FOR EASTERN WESTMORELAND AND FAYETTE COUNTIES TUESDAY NIGHT GIVEN BL FLOW SHOULD ERADICATE COLD AIR AT THE SFC EVEN ACROSS THE DEEPER VALLEYS BETWEEN CHESTNUT AND LAUREL RIDGES. FARTHER NORTH...CONFIDENCE IS HIGHER FOR COLD AIR TO STAY LOCKED IN PLACE...WHICH FOLLOWS CLIMOTOLOGICAL NORM. CLARION COUNTY WAS THROWN IN...HOWEVER THEY SHOULD SWITCH OVER TO RAIN A FEW HOURS SOONER THAN THEIR COUNTERPARTS TO THE NORTH /FOREST/ AND EAST /JEFFERSON/. ONE POSITIVE THING HEADING INTO THIS EVENT IS GIVEN THE RECENT WARM WEATHER...THE GROUND WILL NOT BE AS COLD AS IT WAS FOR THE ICING EVENT IN MID NOVEMBER. WE STILL DO NOT EXPECT A SIGNIFICANT ICE STORM FOR ANY OF OUR COUNTIES. IF THE SOUTHEAST WINDS ARE STRONG THAN EXPECTED...IT IS POSSIBLE THE GARRETT AND TUCKER COULD SEE IN EXCESS OF A QUARTER OF AN INCH...BUT AFTER REVIEW OF PLUME DIAGRAMS FOR 2G4 AND PIE SIDED WITH THE MEAN OF THE PAST FEW RUNS WHICH PLACES STORM TOTAL ICE ACCUMULATION AROUND 0.15 TO 0.20 INCHES. A QUARTER OF AN INCH OF ICE IS NEEDED FOR AN ICE STORM WARNING. TEMPERATURES WERE A BLEND OF THE ONGOING FORECAST AND THE ADJMET BIAS CORRECTED GRIDS. A GRADUAL WARM UP TO SEASONAL NUMBER IN THE LOWER TO MID 40S IS SLATED FOR MID WEEK. && .LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/... SYSTEM DEVELOPING ACROSS THE CENTRAL PLAINS WILL PUSH NORTHEAST INTO THE REGION THURSDAY NIGHT INTO FRIDAY. HAVE KEPT POPS IN THE FORECAST LONGER WITH THE FRONT...AS PRECIPITATION MAY NOW LINGER INTO SATURDAY AND POSSIBLY EVEN SATURDAY NIGHT IF THE 00Z ECMWF SOLUTION IS CORRECT. COULD POSSIBLY SEE MIXED PRECIPITATION EACH NIGHT DEPENDING ON TEMPERATURES. RIDGE OF HIGH PRESSURE BUILDS IN BY SUNDAY...ALLOWING FOR A RETURN TO DRY WEATHER. TEMPERATURES WILL BE SEASONABLE THROUGH THE PERIOD. && .AVIATION /16Z MONDAY THROUGH FRIDAY/... COLD FRONT WILL COMPLETE ITS PASSAGE OF THE FORECAST AREA BY LATE MORNING...VEERING THE WINDS AT ALL SITES TO NORTHWEST. MGW IS ONLY SITE THAT HAS NOT DROPPED TO IFR CONDITIONS...WITH LIMITED CONFIDENCE THAT IFR CIGS WILL OCCUR. HAVE TRENDED SLIGHTLY SLOWER WITH RECOVERY TO VFR FROM 06Z TAF ISSUANCE...BUT ALL SITES SHOULD REACH VFR BY LATE AFTERNOON. OUTLOOK.../TUESDAY THROUGH FRIDAY/... MVFR RESTRICTIONS ARE LIKELY WITH AS A COLD FRONT PASSES MID WEEK. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 11 PM EST TUESDAY FOR MDZ001. OH...NONE. PA...FREEZING RAIN ADVISORY FROM 7 AM TUESDAY TO 7 AM EST WEDNESDAY FOR PAZ009-015-016-023. FREEZING RAIN ADVISORY FROM 7 AM TO 9 PM EST TUESDAY FOR PAZ074-076. WV...FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 11 PM EST TUESDAY FOR WVZ023-041. && $$ SYNOPSIS...98 NEAR TERM...98 SHORT TERM...98
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
342 PM EST MON DEC 1 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 336 PM EST MON DEC 1 2014 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A PROGRESSIVE... NEARLY W-E FLOW ALONG THE CNDN BORDER. SHRTWV EMBEDDED WITHIN THIS FLOW IS CURRENTLY MOVING THRU ERN ONTARIO. LLVL NW FLOW/H85 THERMAL TROF WITH TEMPS AS LO AS -25 TO -28C RESULTED IN NUMEROUS LK EFFECT SN SHOWERS MAINLY IN THE W-NW WIND SN BELTS. BUT STRONG SUBSIDENCE RELATED TO DNVA/DEEP LYR QVECTOR DVGC THAT LOWERED THE INVRN BASE TO H9-925 AS SHOWN ON THE 12Z INL/MPX RAOBS AS WELL AS TENDENCY FOR THE LLVL FLOW TO BECOME MORE ACYC WITH APRCH OF SFC HI PRES IN SRN MN IS LIMITING THE INTENSITY OF THE SN SHOWERS. THE SN SHOWERS ARE ALSO SHIFTING AS THE FLOW BEGINS TO BACK WITH HI PRES MOVING INTO WI. NW WIND GUSTS REACHED 45-50 MPH ALONG LK SUP DURING THE MRNG...BUT WEAKENING PRES GRADIENT FOLLOWING PASSAGE OF PRES RISE CENTER THIS MRNG IS CAUSING WINDS TO SLOWLY DIMINISH. THE HI WAVES WHIPPED UP BY THESE STRONG WINDS...AS HI AS 15 FT...AND ABOVE NORMAL LK WATER LVLS WARRANTED ISSUANCE OF A LK SHORE FLOOD ADVY FOR THE MORE EXPOSED ALGER/LUCE COUNTIES THAT WL EXPIRE AT 2/00Z. LOOKING TO THE W... SKIES ARE MOCLR IN MN UNDER HI PRES RDG/AXIS OF LOWEST PWAT OF 0.03 INCH /10-15 PCT OF NORMAL/ REPORTED ON THE 12Z MPX/INL RAOBS...BUT MORE HI CLDS IN ADVANCE OF A SHRTWV MOVING THRU THE PAC NW/SW CANADA ARE ALREADY PUSHING INTO WRN MN. MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON LES TRENDS LATE TODAY...LO TEMPS TNGT WITH PASSAGE OF SFC RDG/VERY DRY AIRMASS AND THEN POTENTIAL FOR SOME WAA PCPN ON TUE IN THE STRENGTHENING S FLOW BTWN THE DEPARTING HI PRES AND LO PRES TROF ASSOCIATED WITH SHRTWV NOW MOVING THRU THE ROCKIES. LATE TODAY/TNGT...AS THE SFC HI PRES CENTER IN SRN MN SHIFTS E THRU WI...NRN LOWER MI AND INTO QUEBEC BY 12Z TUE...THE WINDS WL BACK STEADILY TO THE S...CAUSING LINGERING SN SHOWERS IN THE W-NW WIND SN BELTS TO SHIFT OUT INTO THE LK BY MIDNGT OR SO. WINDS WL ALSO DIMINISH THIS EVNG WITH THE ARRIVAL OF THE WEAKER GRADIENT ASSOCIATED WITH THE HI. CONSIDERING THE VERY DRY INCOMING AIRMASS... EXPECT TEMPS OVER MUCH OF THE CWA TO DIP AOB ZERO THIS EVNG. BUT INCOMING HI CLDS RELATED TO STRENGTHENING S FLOW/ISENTROPIC ASCENT UNDER SHARPENING PRES GRADIENT BTWN DEPARTING SFC HI TO THE E AND LO PRES TROF IN THE PLAINS WL TEND TO LIMIT THE DIURNAL TEMP FALL AND CAUSE TEMPS TO RISE OVERNGT. DESPITE THESE LIMITATIONS...TENDED TO LOWER GOING FCST MIN TEMPS TOWARD -10F OVER THE INTERIOR W AND SCENTRAL. ANOTHER CONCERN IS POTENTIAL FOR SOME SN SHOWERS TO DVLP OVERNGT DOWNWIND OF LK MI IN THE S FLOW AND IN PRESENCE OF H85 TEMPS AS LO AS -8 TO -10C /VS LK WATER TEMP ARND 5C AS REPORTED ON THE NRN LK MI BUOY/. THE MAIN LIMITING FACTOR ON THE COVERAGE/INTENSITY OF THESE SN SHOWERS WL BE LO INVRN BASE FCST NEAR 3K FT AGL AND VERY DRY NATURE OF THE LLVL AIR. THESE SN SHOWERS WL IMPACT MAINLY DELTA COUNTY AFTER 06Z. TUE...AREA OF DEEP LYR QVECTOR CNVGC ASSOCIATED WITH DPVA IN ADVANCE OF APRCHG SHRTWV/PERSISTENT ISENTROPIC ASCENT IN THE SW FLOW BTWN ACCOMPANYING SFC TROF AND DEPARTING HI PRES IN SE CANADA ARE FCST TO IMPACT THE CWA. THE MAIN LIMITING FACTOR TO WIDESPREAD PCPN WL BE MARGINAL MSTR RETURN ARND THE H85 LEVEL. SINCE THE MODELS SHOW SOME HIER H85 DEWPTS ADVECTING INTO THE E HALF IN THE AFTN UNDER THE DEEP LYR FORCING AND WHERE THERE WL REMAIN A LK EFFECT COMPONENT IN THE SW FLOW OFF LK MI WITH H85 TEMPS NEAR -8C...FCST THE HIER POPS/PCPN TOTALS IN THAT AREA. NOT OUT OF THE QUESTION THERE COULD BE A FEW INCHES OF SN IN THE ERN CWA. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 313 PM EST MON DEC 1 2014 A VERY PROGRESSIVE PATTERN IS EXPECTED FOR THE LONG TERM FORECAST...AS THE NORTHERN STREAM JET SLIDES NORTH INTO SOUTHERN CANADA AND SWEEPS A SERIES OF COLD FRONTS OR TROUGHS EAST ACROSS THE AREA. BETWEEN THE FRONTS/TROUGHS...AREAS OF HIGH PRESSURE WILL MOVE THROUGH THE REGION WHICH WILL PROVIDE PERIODS OF PARTLY CLOUDY TO CLEAR SKIES OVER THE AREA. WITH THE NORTHERN STREAM OF THE JET SLIDING FARTHER TO THE NORTH...SHOULD SEE A GRADUAL MODERATION TO THE TEMPERATURES THIS WEEK...POTENTIALLY EVEN BEING A FEW DEGREES ABOVE NORMAL ON SATURDAY/SUNDAY (NORMAL HIGHS IN THE UPPER 20S TO LOWER 30S). THE FIRST TROUGH WILL SWEEP ACROSS THE UPPER GREAT LAKES REGION ON TUESDAY EVENING...SHIFTING THE GUSTY SOUTHERLY WINDS TO THE WEST BY WEDNESDAY MORNING. AHEAD OF THE TROUGH...EXPECT THERE TO BE SOME LINGERING LAKE EFFECT OFF LAKE MICHIGAN OVER DELTA/SCHOOLCRAFT INTIALLY IN THE EVENING...BUT QUICKLY DEPARTING WITHIN A COUPLE HOURS. AS THAT DEPARTS...THE INITIAL SURGE OF ENERGY AND DEEPER MOISTURE FROM THE SHORTWAVE WILL MOVE THROUGH THE EASTERN CWA AND PRODUCE AN INCREASE IN COVERAGE/INTENSITY OF THE SNOW SHOWERS. SOME LOCATIONS MIGHT PICK UP A QUICK INCH OR TWO OF SNOW BEFORE IT DEPARTS SHORTLY AFTER MIDNIGHT. BEHIND THE TROUGH...BOUNDARY LAYER WINDS WILL SHIFT TO THE WEST OR WEST-NORTHEST AND PRODUCE SOME LIGHT LAKE EFFECT SNOW SHOWERS. ALTHOUGH 875MB TEMPS FALL TO AROUND -15C...THE STRENGTH OF THE INVERSION AT THAT LEVEL WILL LIKELY KEEP THE CLOUD DEPTH LIMITED AND IN TURN THE SNOWFALL AMOUNTS LIGHT. THAT WILL CONTINUE THROUGH WEDNESDAY MORNING UNTIL A SECONDARY TROUGH MOVES THROUGH ON WEDNESDAY AFTERNOON (ASSOCIATED WITH ANOTHER SHORTWAVE ON THE WEST SIDE OF THE DEPARTING UPPER TROUGH). THAT SHORTWAVE WILL USHER IN COLDER 850MB TEMPS (TO -16C)...WHILE PROVIDING DEEPER MOISTURE AND RAISING INVERSION HEIGHTS TO 7-8KFT. THAT WILL LEAD TO A 6-12HR PERIOD OF LIGHT TO MODERATE LAKE EFFECT SNOW IN THE WEST-NORTHWEST WIND LOCATIONS. WHILE MUCH OF THE CLOUD IS WITHIN THE DGZ...THINKING THE STRENGTH OF THE WINDS (GUSTING TO 30-40MPH) WILL HELP FRACTURE THE DENDRITES AND LEAD TO SNOW RATIOS LOWER THAN NORMALLY EXPECTED IN THAT SITUATION. THAT PERIOD OF LAKE EFFECT WILL QUICKLY DIMINISH FROM WEST TO EAST WEDNESDAY NIGHT...AS AN AREA OF HIGH PRESSURE SHIFTS EAST INTO THE AREA. THIS HIGH WILL CONTINUE TO THE EAST ACROSS THE UPPER GREAT LAKES REGION ON THURSDAY MORNING AND BRING AN END TO MOST OF THE LAKE EFFECT (OR AT LEAST PUSH IT OVER EASTERN LAKE SUPERIOR AS WINDS BACK). WINDS WILL BACK TO THE SOUTH BEHIND THE HIGH ON THURSDAY AFTERNOON AND NIGHT...AHEAD OF THE NEXT TROUGH THAT WILL MOVE THROUGH THE AREA ON FRIDAY INTO FRIDAY NIGHT. THIS PERIOD SHOULD BE FAIRLY QUIET AND EXPECT HIGHS TO RISE TOWARDS NORMAL ON FRIDAY. WITH THE TROUGH BEING FAIRLY WEAK AS IT MOVES THROUGH...DON/T EXPECT MUCH CHANGE IN THE CONDITIONS BEHIND THE FRONT AS COLDEST 850MB TEMPS ARE LOCKED UP WELL TO THE NORTH AND GENERALLY HAVE VALUES AROUND -4C OVER LAKE SUPERIOR. THIS LEADS TO MARGINAL LAKE EFFECT CLOUD DELTA-T VALUES FRIDAY NIGHT INTO SATURDAY AS THE NEXT AREA OF HIGH PRESSURE MOVES IN. WITH LIMITED LOW LEVEL MOISTURE SHOWN ON THE MODELS...WILL JUST GO WITH PARTLY CLOUDY SKIES OVER THE AREA...ESPECIALLY IN AREAS FAVORED BY NORTHWEST WIND. THAT NEXT AREA OF HIGH PRESSURE WILL DEPART ON SATURDAY NIGHT ALLOWING THE NEXT SHORTWAVE AND SURFACE LOW/TROUGH TO APPROACH THE AREA FROM THE DAKOTAS SUNDAY INTO SUNDAY NIGHT. WILL FOLLOW A GENERAL CONSENSUS OF THE GFS/ECMWF AT THIS POINT AND SHOW SLIGHT CHANCE POPS SPREADING ACROSS THE AREA. THE BIGGEST DIFFERENCE BETWEEN THE MODELS COMES FROM THE AMOUNT OF COLD AIR THAT MOVES IN BEHIND THE LOW/TROUGH ON MONDAY (850MB TEMPS OF -4C ON THE GFS AND -8C ON THE ECMWF). EITHER WAY...THIS APPEARS MARGINAL FOR LAKE EFFECT AND WILL SHOW DIMINISHING POPS ON MONDAY AS THE SYSTEM DEPARTS. ALL IN ALL...SATURDAY THROUGH MONDAY THE AREA SHOULD SEE TEMPERATURES A LITTLE ABOVE NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1241 PM EST MON DEC 1 2014 EXPECT LINGERING LES AND IFR/LIFR CONDITIONS AT IWD TO GIVE WAY TO VFR CONDITIONS BY LATE AFTN AS WINDS/BLSN DIMINISH AND THE LLVL WINDS BACK TOWARD THE SW AND DRIVE THE SHSN N OF THIS SITE. THESE SAME TRENDS WL OCCUR AT CMX LATER...WITH THE VFR CONDITIONS NOT ARRIVING UNTIL LATER IN THE EVNG. AT SAW...MVFR CIGS AT TIMES EARLY IN THE FCST PERIOD WL GIVE WAY TO VFR CONDITIONS AS LARGER SCALE SUBSIDENCE/DOWNSLOPE WNW FLOW DISSIPATES THE CLDS. FCST LLWS AT ALL THE SITES OVERNGT ONCE THE FLOW SHIFTS TO THE S AND INCREASES ABOVE SHALLOW RADIATION INVRN UNDER TIGHTENING PRES GRADIENT BTWN DEPARTING HI PRES TO THE E AND A LO PRES TROF IN THE PLAINS. THESE STRONGER WINDS WL TEND TO MIX OUT A BIT ON TUE MRNG AND RESULT IN SOME GUSTY SFC WINDS. AFTER THE LK EFFECT CLDS DIMINISH THIS AFTN/ EVNG...VFR CONDITIONS WL PREDOMINATE. THE ONLY EXCEPTION MAY BE AT SAW...WHERE S FLOW OFF LK MI MIGHT DRIVE SOME MVFR SC CIGS FAR ENUF N TO IMPACT THAT SITE. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 336 PM EST MON DEC 1 2014 EXPECT WINDS/FREEZING SPRAY TO DIMINISH AND BACK TOWARD THE W AND SW WITH PASSAGE OF SFC HI PRES RDG THIS EVNG. ALLOWED GOING HEAVY FREEZING SPRAY/GALE HEADLINES OVER THE EASTERN LAKE TO END AS PLANNED. BUT AS THE HI MOVES STEADILY TO THE E AND ANOTHER LO PRES TROF MOVES INTO THE NORTHERN PLAINS TONIGHT...THE PRES GRADIENT WILL SHARPEN AND CAUSE S WINDS TO INCREASE. THERE WILL BE A PERIOD OF S GALES MAINLY OVER THE E HALF OF THE LAKE ON TUE WHEN THE SHARPEST GRADIENT WILL PASS OVERHEAD. ISSUED A GALE WARNING FOR LAKE SUPERIOR OPEN WATER ZONES 264>267. THIS GALE EVENT WILL BE RELATIVELY SHORT LIVED AS THE TROF/WEAKER GRADIENT PASSES W-E THROUGH THE UPPER LAKES LATE TUE...WITH GALES ENDING TUE EVENING. THERE IS LIKELY TO BE ANOTHER W-NW GALE EVENT WED AFTERNOON/NIGHT FOLLOWING A COLD FRONTAL PASSAGE. BUT SINCE THE WEATHER PATTERN IS PROGRESSIVE...THE PASSAGE OF THE TRAILING HI PRES RIDGE THRU THE AREA ON THU WILL RESULT IN DIMINISHING/BACKING WINDS TO THE SW FOR LATER IN THE WEEK. NO GALES ARE EXPECTED DURING THIS TIME. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKESHORE FLOOD ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ006- 007. LAKE SUPERIOR... GALE WARNING FROM 10 AM TO 7 PM EST TUESDAY FOR LSZ267. GALE WARNING FROM 7 AM TO 7 PM EST TUESDAY FOR LSZ266. GALE WARNING FROM 7 AM TO 1 PM EST TUESDAY FOR LSZ264-265. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...SRF AVIATION...KC MARINE...KC
AREA FORECAST DISCUSSION
NWS BILLINGS MT
248 PM MST MON DEC 1 2014 .SHORT TERM...VALID FOR TUE AND WED... SURFACE TROUGH OVER CENTRAL ZONES PULLING EAST WITH TEMPERATURES CLIMBING THROUGH THE 20S IN MOST LOCATIONS WITH A FEW EXCEPTIONS. HIGHER ELEVATIONS ARE THE WARM SPOTS WITH AREAS WITH TIMBERCREST RAWS AT 40 WHILE A FEW SHELTERED LOCATIONS LIKE LITTLE BIG HORN ARE STILL IN SINGLE DIGITS. THIS DEPARTURE OF THE ARCTIC LOOKS TO BE PERMANENT AS SPEEDY CYCLONIC FLOW ALOFT WILL BRING A SERIES OF WEAK PACIFIC SYSTEMS ACROSS THE AREA. WATER VAPOR SHOWS DRY AIR GETTING DRAGGED INTO THE AREA AHEAD OF THE CYCLONIC FLOW IS LIMITING THE NORTHWARD PROGRESS OF MOISTURE THAT IS BEING PUSHED OUT OF THE EASTERN PACIFIC BY A LOW OFF THE CALIFORNIA COAST. THIS MOISTURE IS STREAMING INTO IDAHO AND SOUTHWEST MONTANA AND COOKE CITY CAMS DO SHOW SOME SNOW BUT DEWPOINTS IN THE TEENS AT DERBY MOUNTAIN AND TIMBERCREST SHOW THIS IS ONLY IMPACTING THE BACKSIDE OF THE BEARTOOTHS AND THE ABSAROKAS. RUC CONSISTENTLY HOLDING THIS SNOW OUT OF THE LOWER ELEVATIONS BUT DO HAVE 4 TO 8 INCH MOUNTAIN ACCUMULATIONS EXPECTED OVERNIGHT. AS AXIS OF CYCLONIC FLOW SHIFTS THROUGH THE REGION TONIGHT IT DOES ALLOW THE SURFACE TROUGH TO PULL EASTWARD AS A WEAK FRONT. HIGH PRESSURE BEHIND THIS FRONT IS VERY LIMITED AS IT IS NOT A STRONG AIRMASS CHANGE SO TONIGHTS TEMPERATURES WILL BE MUCH WARMER TONIGHT THAN PREVIOUS NIGHT. THERE IS A WINDOW OF SOME GAP FLOW WINDS IN THE LIVINGSTON AREA THIS EVENING BUT THEY WILL WANE AS THE BOUNDARY SHIFTS SOUTH OF THE AREA. TUESDAY ANOTHER BOUNDARY SHIFTS ACROSS THE AREA WITH A BETTER POCKET OF HIGH PRESSURE BEHIND IT. THIS SETS UP A BREEZY DAY WITH NORTHWEST WINDS SO DESPITE A MUCH WARMER START TEMPERATURES WILL NOT CLIMB PAST THE 30S. HIGH RISES KICKING IN TUESDAY NIGHT STRENGTHEN THIS HIGH AS IT MOVES INTO EASTERN MONTANA SO SURFACE FLOW BECOMES LIGHT AND RADIATIONAL COOLING WILL BRING A SHOT AT SINGLE DIGIT TEMPERATURES ACROSS THE EASTERN HALF OF THE AREA. WEDNESDAY AN UPPER LEVEL RIDGE AXIS THAT HAS A BUNCH OF ENERGY FLOWING THROUGH IT CAUSES HEIGHTS TO RISE OVER THE AREA. THIS SUPPORTS ANOTHER BIT OF MODERATION WITH CONTINUED DRY WEATHER. BORSUM .LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON... MINIMAL CHANGES THROUGH THE LONG TERM PERIOD...WITH GENERALLY QUIET WEATHER THROUGHOUT THE PERIOD. MODELS REMAIN IN PRETTY GOOD AGREEMENT THROUGH EARLY SATURDAY...WHERE MODELS BEGIN TO DIVERGE. A DIRTY RIDGE DEVELOPS OVER IDAHO AND WESTERN MONTANA BY THURSDAY...WITH A GOOD TAP PACIFIC MOISTURE STREAMING INTO THE WESTERN MOUNTAINS. A STRONGER WAVE WILL ROTATE THROUGH THURSDAY...GIVING A CHANCE FOR POPS INTO THE FOOTHILLS AND NEAR WESTERN PLAINS...BUT STILL NOT EXPECTING SIGNIFICANT ACCUMULATIONS OTHER THAN THE MOUNTAINS. SHORTWAVE RIDGING BUILDS IN FOR FRIDAY INTO SATURDAY...POINTING TO A MORE SIGNIFICANT WARM UP...AND DRY WEATHER. MODELS INDICATE A STRONGER PACIFIC SYSTEM PUSHING INTO THE REGION SATURDAY NIGHT...BUT DIFFER ON STRENGTH OF THE WAVE AND AMOUNT OF MOISTURE. GFS SWEEPS THE WAVE ACROSS THE REGION BRINGING A CHANCE FOR PRECIP ACROSS THE AREA THROUGH SUNDAY...WHILE EC BRINGS WEAKER WAVE...AND SHIFT BULK OF MOISTURE TO THE NORTH. HAVE INTRODUCED SLIGHT POPS FOR THE SATURDAY NIGHT PERIOD...BUT ONLY PLACEHOLDER...FLURRY TYPE...POPS IN FOR SUNDAY AT THIS POINT. THE RIDGE APPEARS TO REDEVELOP OVERNIGHT SUNDAY NIGHT...AND GENERALLY PERSISTS THROUGH THE END OF THE PERIOD. TEMPS IN 40S CAN BE EXPECTED THROUGHOUT THE EXTENDED PERIOD...PEAKING WITH HIGHS NEAR 50 FOR FRIDAY AND SATURDAY. AAG && .AVIATION... GUSTY SOUTHWEST WINDS FROM BILLINGS WEST...INCLUDING BIL AND KLVM WILL TAPER OFF OVERNIGHT AND THROUGH TUESDAY MORNING. MAINLY VFR CONDITIONS CAN BE EXPECTED THROUGH TONIGHT ACROSS MUCH OF THE REGION. A DISTURBANCE CROSSING THE REGION WILL BRING SNOW TO AREA MOUNTAINS...AND EXTREME SOUTHERN AND EASTERN ROUTES OVERNIGHT...INCLUDING KSHR AND KBHK. MOUNTAINS WILL BECOME OBSCURED OVERNIGHT...AS SNOW DEVELOPS...AND MVFR TO IFR CONDITIONS ARE POSSIBLE IN SNOW IN PLAINS REGIONS. AAG && .PRELIMINARY POINT TEMP/POPS... TUE WED THU FRI SAT SUN MON ----------------------------------------------------------- BIL 018/034 010/033 019/045 027/048 027/050 025/043 025/042 11/B 00/B 12/W 11/B 00/B 21/B 00/B LVM 022/037 014/040 029/045 029/046 028/050 025/044 027/041 11/B 01/B 13/W 22/W 11/B 21/B 11/B HDN 015/034 006/033 015/044 022/046 022/050 021/043 021/043 11/B 00/B 12/J 11/B 00/B 21/M 00/B MLS 008/027 002/029 009/038 016/041 019/044 019/039 018/039 00/B 00/B 01/B 11/B 00/B 11/M 00/B 4BQ 016/033 005/034 014/042 018/044 022/044 020/041 020/039 11/B 00/B 01/B 11/U 00/B 11/M 00/B BHK 011/025 004/028 011/035 015/040 019/040 018/035 016/036 02/J 00/U 01/B 00/B 00/B 11/M 00/B SHR 020/036 010/038 021/045 023/046 021/049 020/044 022/042 22/J 00/B 12/W 11/B 00/B 22/W 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND TUESDAY ISSUED AT 246 PM CST MON DEC 1 2014 THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW ARCTIC HIGH PRESSURE MOVING INTO THE NORTHERN MISSISSIPPI VALLEY EARLY THIS AFTERNOON. WINDS ARE GRADUALLY DIMINISHING AS THIS HIGH PRESSURE DRAWS CLOSER TO THE REGION...BUT TEMPERATURES HAVE STRUGGLED TO RISE SO FAR TODAY. WIND CHILLS REMAIN BETWEEN 0 AND 10 DEGREES BELOW ZERO. CLEAR SKIES EXIST ALL THE WAY ACROSS THE NORTHERN PLAINS...BUT THE NEXT SYSTEM IS MOVING ACROSS THE PACIFIC NORTHWEST. FORECAST CONCERNS ARE THREE FOLD...AND INCLUDE MIN TEMPS TONIGHT...SMALL LAKE EFFECT SNOW CHANCES LATE TONIGHT INTO TUESDAY MORNING...AND LIGHT SNOW CHANCES OVER N-C WISCONSIN FOR TUESDAY AFTERNOON. TONIGHT...ARCTIC HIGH PRESSURE WILL QUICKLY SLIDE ACROSS THE REGION THIS EVENING AND HEAD TOWARDS NEW ENGLAND BY LATE TONIGHT. THOUGH THE COLDEST AIR WILL HAVE DEPARTED THE REGION TO THE EAST...CLEAR SKIES AND LIGHT WINDS WILL PROMOTE TUMBLING TEMPERATURES THIS EVENING. ALWAYS DIFFICULT TO DETERMINE HOW LOW TO GO IN THESE INSTANCES BECAUSE THE COLD SPOTS CAN QUICKLY FALL 20 DEGREES IN JUST A FEW HOURS. UPSTREAM OBS THIS MORNING SHOWED PLENTY OF READINGS IN THE 10 TO 15 BELOW RANGE AND THATS A GOOD START FOR THE COLD SPOTS OF N-C WISCONSIN. AS THE SURFACE HIGH EXITS...THE SURFACE PRESSURE GRADIENT RAPIDLY TIGHTENS AND SHOULD SEE TEMPERATURES RISE LATE IN THE EVENING AND OVERNIGHT...WHEN CIRRUS ARRIVES. ADDITIONALLY...SURFACE TO 950MB WINDS WILL SHIFT TO THE SOUTHEAST OVER LAKE MICHIGAN OVERNIGHT WHICH WILL LIKELY BRING STRATO-CU AND FLURRIES TO MUCH OF EASTERN WISCONSIN. KEPT A SMALL ACCUMULATION OVER THE DOOR...BUT THINKING ONLY A DUSTING AT BEST DUE TO THE VERY DRY AIRMASS IN PLACE. LOWS 0 TO 5 ABOVE OVER THE FOX VALLEY AND LAKE SHORE. TUESDAY...AS LAKE EFFECT CLOUDS AND FLURRIES IMPACT EASTERN WISCONSIN...MID AND HIGH CLOUDS WILL BE SPREADING OVERHEAD DURING THE MORNING AHEAD OF A SHEARED SHORTWAVE. THINK THE CLOUDS AND FLURRIES WILL BECOME INCREASINGLY CONFINED TO THE LAKE SHORE AS LOW LEVEL WINDS VEER TO THE SOUTH AND THEN SSW DURING THE MORNING. DO NOT SEE MUCH POTENTIAL FOR SEEDER-FEEDER PROCESSES DUE TO A VERY DRY LAYER BETWEEN 900-700MB. AS THE SHORTWAVE DRAWS CLOSER DURING THE AFTERNOON...PROGGED SOUNDINGS OVER N-C WISCONSIN SHOW THAT DRY WEDGE ERODING. WITH FORCING FROM DECENT MID-LEVEL FGEN...CAN SEE A LIGHT SNOW CHANCE FOR THE NORTH BY MID AFTERNOON. WILL INCREASE PRECIP CHANCES SOME. HIGHS RETURNING TO THE 20S. .LONG TERM...TUESDAY NIGHT THROUGH MONDAY ISSUED AT 246 PM CST MON DEC 1 2014 WINTER IS TAKING A VACATION FOR THE NEXT WEEK OR SO AS UPPER HEIGHTS RISE AND FLOW BECOMES ZONAL. OTHER THAN SOME LIGHT SNOW OR FLURRIES WITH A WEAK COLD FRONT TUESDAY NIGHT IT LOOKS LIKE IT WILL BE DRY THROUGH THE REMAINDER OF THE WEEK. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1123 AM CST MON DEC 1 2014 VFR CONDITIONS ARE ANTICIPATED THROUGH THE EVENING AS ARCTIC HIGH PRESSURE MOVES ACROSS THE REGION. AS THIS HIGH SHIFTS TO THE CENTRAL GREAT LAKES OVERNIGHT...WINDS WILL TURN ONSHORE OFF LAKE MICHIGAN...WHICH WILL LIKELY PUSH MVFR STRATUS AND FLURRIES INTO EASTERN WISCONSIN. STILL QUESTIONABLE HOW FAR INLAND THESE CLOUDS WILL REACH...BUT THINKING MAINLY EAST OF ROUTE 41 AT THE MOMENT. THESE CLOUDS WILL RETREAT BACK TOWARDS THE LAKE BY MIDDAY TUESDAY. ELSEWHERE...MID AND HIGH CLOUDS WILL BE ON THE INCREASE LATE TONIGHT THROUGH TUESDAY MORNING. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......RDM AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1137 AM CST MON DEC 1 2014 .UPDATE... ISSUED AT 1006 AM CST MON DEC 1 2014 WIND CHILLS HAVE IMPROVED THIS MORNING. THEREFORE...THE WIND CHILL ADVISORY HAS BEEN CANCELLED. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 206 AM CST MON DEC 1 2014 CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED TROUGHS ALONG THE BRITISH COLUMBIA COAST AND FROM NORTHERN ONTARIO INTO CENTRAL MN....WITH WEAK RIDGING IN-BETWEEN OVER MONTANA AND ALBERTA. SOME PACIFIC MOISTURE WAS STREAMING INTO SOUTHERN PORTIONS OF THE FORECAST AREA AHEAD OF THE CENTRAL MN TROUGH... MANIFESTING ITSELF AS HIGH CLOUDS. CLEAR SKIES DOMINATE THE REST OF THE FORECAST AREA INTO THE NORTHERN PLAINS...RESULTING FROM A DRY ARCTIC AIRMASS IN PLACE. PRECIPITABLE WATER VALUES OF 0.10 INCHES OR LESS...20 TO 40 PERCENT OF NORMAL...WERE OBSERVED ON 00Z SOUNDINGS. MEANWHILE...925MB TEMPS WERE IN THE -15 TO -18C RANGE. THE COMBINATION OF THE CLEAR SKIES...DRY AIR...NIGHT TIME COOLING AND SOME SNOWPACK HAS ALLOWED READINGS TO DIP INTO THE SINGLE DIGITS BELOW ZERO ACROSS PORTIONS OF SOUTHEAST MN AND NORTH CENTRAL WI...AND SINGLE DIGITS ABOVE ZERO TO MID TEENS ELSEWHERE. A PERSISTENT 5 TO 15 MPH BREEZE HAS RESULTED IN WIND CHILLS OF ZERO TO 15 BELOW ZERO. THE SURFACE HIGH ASSOCIATED WITH THE ARCTIC AIR WAS STILL SITUATED OVER THE DAKOTAS. VERY CHILLY CONDITIONS START OFF THE FIRST DAY OF DECEMBER. ALTHOUGH PLENTY OF SUNSHINE IS EXPECTED AS THE SURFACE HIGH OVER THE DAKOTAS EVENTUALLY MOVES OVERHEAD BY SUNSET...925MB TEMPS IN THE -16C SOUTH TO -20C NORTH AT 18Z WILL LIMIT TEMPERATURES FROM CLIMBING TOO MUCH. 2 METER MODEL OUTPUT AND VARIOUS MOS GUIDANCE ARE ALL IN VERY GOOD AGREEMENT FOR TODAYS HIGHS...WITH READINGS MAINLY BETWEEN 5 AND 15 ABOVE. SHOULD THESE COME TO PASS...WE ARE LOOKING AT ONE OF THE TOP 5 COLDEST HIGHS FOR DECEMBER 1ST. WIND CHILLS WILL REMAIN AN ISSUE TO CONTEND WITH THIS MORNING AS THE 5 TO 15 MPH BREEZE PERSISTS. EXPECT DIMINISHING WINDS IN THE AFTERNOON COMBINED WITH CLIMBING TEMPERATURES TO HELP IMPROVE WIND CHILLS. CLEAR SKIES...VERY DRY AIR AND LIGHT WINDS EARLY THIS EVENING WITH THE SURFACE HIGH IN PLACE SHOULD PROMOTE A RAPID TEMPERATURE DROP AFTER SUNSET. SOME LOCATIONS COULD SEE A DROP OF 10 TO 15 DEGREES BETWEEN 21-00Z. MODELS ARE IN GOOD AGREEMENT PUSHING THE HIGH QUICKLY OFF TO THE EAST DURING THE NIGHT...MOVING INTO EASTERN WI BY 06Z AND LOWER MI BY 12Z. THIS ALLOWS THE GRADIENT TO TIGHTEN UP AND THUS AN INCREASE OF SOUTHERLY WINDS TO BRING WARMER AIR BACK INTO THE REGION. THE PROBLEM WE COULD RUN INTO IS WIND CHILLS BACK DOWN TO ADVISORY CRITERIA OF -20...DUE TO THE ONSET OF THE WINDS WITH THE COLD TEMPERATURES IN THE EVENING. THUS...ANOTHER WIND CHILL ADVISORY MAY BE NEEDED FOR SOME AREAS AFTER THE CURRENT ONE ENDS. TAYLOR COUNTY APPEARS TO BE THE BEST CANDIDATE FOR AN ADVISORY WITH SOME OF SOUTHEAST MN PERHAPS NEEDING INCLUSION AS WELL. AN INCREASING MID CLOUD DECK TOWARDS 12Z ACCOMPANYING THE WARM ADVECTION SHOULD ALSO HELP TO GIVE TEMPERATURES A BOOST. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 206 AM CST MON DEC 1 2014 FOCUS/ATTENTION FOR THE TUESDAY THROUGH WEDNESDAY TIME PERIOD REMAINS ON THE CURRENT UPPER TROUGH ALONG THE BRITISH COLUMBIA COAST. MODEL AGREEMENT REMAINS GOOD BRINGING THIS TROUGH ACROSS THE NORTHERN PLAINS TUESDAY...ITS AXIS OVER THE FORECAST AREA BY 12Z WEDNESDAY...AND OFF INTO THE EASTERN GREAT LAKES BY 00Z THU. AHEAD OF THE TROUGH FOR TUESDAY...A BRISK SOUTHWEST WIND WILL HELP TO BOOST 925MB TEMPS UP TO -5 TO -8C BY 00Z. THESE READINGS COMBINED WITH SOME SUN FILTERED THROUGH PERIODS OF MID/HIGH CLOUDS SUPPORT HIGHS IN THE 20S TO LOW 30S...WARMEST IN FAR SOUTHWEST WI AND RIVER VALLEYS WHERE SNOW COVER IS LIMITED. AS WE HEAD INTO THE LATE AFTERNOON AND EVENING HOURS...MODEL DISAGREEMENT BEGINS TO SHOW UP NORTH OF I-90 IN THE PRECIPITATION DEPARTMENT. THE 01.00Z NAM AND REGIONAL CANADIAN MODELS WANT TO PRODUCE SOME LIGHT SNOW... ESPECIALLY NORTH OF I-94. THE 01.00Z GFS AND FOR THE MOST PART THE 01.00Z ECMWF ARE DRY. BOTH MODEL GROUPS DEPICT WEAK ISENTROPIC LIFTING IN THE 900-600MB LAYER...BUT THE DIFFERENCE IS THAT THE NAM/REGIONAL CANADIAN HAVE MORE MOISTURE IN THE 900-700MB LAYER. HARD TO SAY AT THIS POINT WHAT THAT LAYER MOISTURE WILL LOOK LIKE SO MAINTAINED SOME LOW CHANCES OF PRECIPITATION NORTH OF I-94 FOR THE LATE AFTERNOON/EVENING HOURS. ANY SNOW SHOULD PUSH OFF TO THE EAST AFTER 06Z AS THE UPPER TROUGH AXIS MOVES IN AND A COLD FRONT PASSES THROUGH. THIS COLD FRONT WILL USHER IN SLIGHTLY COOLER AIR FOR WEDNESDAY AS 925MB TEMPS FALL TO -6 TO -10C. THERE SHOULD BE PLENTY OF SUN ON WEDNESDAY AS DRY AIR AND SUBSIDENCE MOVES IN BEHIND THE UPPER TROUGH...SO HIGHS ARE EXPECTED TO BE NEAR OR JUST A LITTLE COOLER THAN TUESDAY. FROM WEDNESDAY NIGHT THROUGH FRIDAY...THE UPPER FLOW IS PROGGED TO BECOME MORE ZONAL...WITH NORTHERN AND SOUTHERN STREAMS BECOMING MORE EVIDENT. THE NORTHERN STREAM LOOKS TO TRACK ACROSS SOUTHERN CANADA WHILE THE SOUTHERN STREAM BECOMES POSITIONED ACROSS THE SOUTHERN U.S.. THE IMPACT TO THE FORECAST AREA FROM THE POSITIONS OF THESE STREAMS IS A WARMING TREND AS PACIFIC AIR FLOWS EASTWARD...AS WELL AS DRY CONDITIONS WITH THE SOUTHERN STREAMING BLOCKING GULF MOISTURE. THERE IS ONE SMALL OPPORTUNITY DURING THIS PERIOD TO PICK UP SOME LIGHT SNOW AND THAT IS ON THURSDAY FROM THE 30.00Z/12Z AND 01.00Z ECMWF. THE ECMWF SUGGESTS A DECENT SHORTWAVE AS WELL AS BAND OF MID LEVEL FRONTOGENESIS AND MOISTURE TO HELP PRODUCE THE SNOW. HOWEVER...ALL OTHER GUIDANCE IS DRY...SUGGESTING THE DRY AIR THAT CAME IN ON WEDNESDAY WILL BE ENOUGH TO ABSORB ANY SNOW FALLING OUT OF THE MID CLOUD. CONSIDERED LEAVING THURSDAY DRY...BUT THE ECMWF CONTINUITY IS CONCERNING. THEREFORE...HAVE ADDED A 20 PERCENT CHANCE TO LOCATIONS NORTH OF I-90. THURSDAYS HIGHS MAY NOT BE MUCH DIFFERENT THAN WEDNESDAY DUE TO CLOUDS MOVING IN AND WARM ADVECTION JUST BEGINNING TO GET IN EARNEST. BETTER SHOT FOR WARMER CONDITIONS COMES FRIDAY AS 925MB TEMPS REACH -2 TO -4C. THOSE READINGS COULD SUPPORT 30S TO LOW 40S...BUT IT APPEARS WE WILL BE BATTLING LOW STRATUS PER ECMWF/GFS 925MB RH FIELDS NEAR SATURATION...THUS HAVE TEMPERED HIGHS SOME. HEADING INTO THE WEEKEND...THE SPLIT FLOW REGIME CONTINUES...WITH HIGH PRESSURE PROGGED AT THE SURFACE. THUS...WE SHOULD SEE A CONTINUATION OF DRY CONDITIONS. SOME DISCREPANCIES EXIST ON HOW WARM THE WEEKEND WILL BE...AND IN PARTICULAR SATURDAY WHERE THE ECMWF DRIVES A LITTLE BIT MORE COLD AIR INTO THE REGION COMPARED TO THE GFS. NEVERTHELESS...READINGS SHOULD BE CLOSE TO NORMAL ON SATURDAY WITH MORE CONFIDENCE OF ABOVE NORMAL ON SUNDAY AS 925MB TEMPS THEN CLIMB TO AT LEAST 0C...IF NOT SLIGHTLY HIGHER. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1137 AM CST MON DEC 1 2014 HIGH PRESSURE SLIDES EAST INTO THE GREAT LAKES REGION OVERNIGHT INTO TUESDAY AS A TROUGH OF LOW PRESSURE MOVES EAST ACROSS THE NORTHERN PLAINS. THIS SETS UP INCREASING SOUTHERLY WINDS OVER THE REGION LATE TONIGHT AND ESPECIALLY ON TUESDAY. EXPECT SOME INCREASE OF MID-LEVEL ALTOCUMULUS CLOUDS AS WELL WITH BASES AOA 8-10KFT. OTHERWISE...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...DAS SHORT TERM...AJ LONG TERM...AJ AVIATION...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1006 AM CST MON DEC 1 2014 .UPDATE... ISSUED AT 1006 AM CST MON DEC 1 2014 WIND CHILLS HAVE IMPROVED THIS MORNING. THEREFORE...THE WIND CHILL ADVISORY HAS BEEN CANCELLED. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 206 AM CST MON DEC 1 2014 CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED TROUGHS ALONG THE BRITISH COLUMBIA COAST AND FROM NORTHERN ONTARIO INTO CENTRAL MN....WITH WEAK RIDGING IN-BETWEEN OVER MONTANA AND ALBERTA. SOME PACIFIC MOISTURE WAS STREAMING INTO SOUTHERN PORTIONS OF THE FORECAST AREA AHEAD OF THE CENTRAL MN TROUGH... MANIFESTING ITSELF AS HIGH CLOUDS. CLEAR SKIES DOMINATE THE REST OF THE FORECAST AREA INTO THE NORTHERN PLAINS...RESULTING FROM A DRY ARCTIC AIRMASS IN PLACE. PRECIPITABLE WATER VALUES OF 0.10 INCHES OR LESS...20 TO 40 PERCENT OF NORMAL...WERE OBSERVED ON 00Z SOUNDINGS. MEANWHILE...925MB TEMPS WERE IN THE -15 TO -18C RANGE. THE COMBINATION OF THE CLEAR SKIES...DRY AIR...NIGHT TIME COOLING AND SOME SNOWPACK HAS ALLOWED READINGS TO DIP INTO THE SINGLE DIGITS BELOW ZERO ACROSS PORTIONS OF SOUTHEAST MN AND NORTH CENTRAL WI...AND SINGLE DIGITS ABOVE ZERO TO MID TEENS ELSEWHERE. A PERSISTENT 5 TO 15 MPH BREEZE HAS RESULTED IN WIND CHILLS OF ZERO TO 15 BELOW ZERO. THE SURFACE HIGH ASSOCIATED WITH THE ARCTIC AIR WAS STILL SITUATED OVER THE DAKOTAS. VERY CHILLY CONDITIONS START OFF THE FIRST DAY OF DECEMBER. ALTHOUGH PLENTY OF SUNSHINE IS EXPECTED AS THE SURFACE HIGH OVER THE DAKOTAS EVENTUALLY MOVES OVERHEAD BY SUNSET...925MB TEMPS IN THE -16C SOUTH TO -20C NORTH AT 18Z WILL LIMIT TEMPERATURES FROM CLIMBING TOO MUCH. 2 METER MODEL OUTPUT AND VARIOUS MOS GUIDANCE ARE ALL IN VERY GOOD AGREEMENT FOR TODAYS HIGHS...WITH READINGS MAINLY BETWEEN 5 AND 15 ABOVE. SHOULD THESE COME TO PASS...WE ARE LOOKING AT ONE OF THE TOP 5 COLDEST HIGHS FOR DECEMBER 1ST. WIND CHILLS WILL REMAIN AN ISSUE TO CONTEND WITH THIS MORNING AS THE 5 TO 15 MPH BREEZE PERSISTS. EXPECT DIMINISHING WINDS IN THE AFTERNOON COMBINED WITH CLIMBING TEMPERATURES TO HELP IMPROVE WIND CHILLS. CLEAR SKIES...VERY DRY AIR AND LIGHT WINDS EARLY THIS EVENING WITH THE SURFACE HIGH IN PLACE SHOULD PROMOTE A RAPID TEMPERATURE DROP AFTER SUNSET. SOME LOCATIONS COULD SEE A DROP OF 10 TO 15 DEGREES BETWEEN 21-00Z. MODELS ARE IN GOOD AGREEMENT PUSHING THE HIGH QUICKLY OFF TO THE EAST DURING THE NIGHT...MOVING INTO EASTERN WI BY 06Z AND LOWER MI BY 12Z. THIS ALLOWS THE GRADIENT TO TIGHTEN UP AND THUS AN INCREASE OF SOUTHERLY WINDS TO BRING WARMER AIR BACK INTO THE REGION. THE PROBLEM WE COULD RUN INTO IS WIND CHILLS BACK DOWN TO ADVISORY CRITERIA OF -20...DUE TO THE ONSET OF THE WINDS WITH THE COLD TEMPERATURES IN THE EVENING. THUS...ANOTHER WIND CHILL ADVISORY MAY BE NEEDED FOR SOME AREAS AFTER THE CURRENT ONE ENDS. TAYLOR COUNTY APPEARS TO BE THE BEST CANDIDATE FOR AN ADVISORY WITH SOME OF SOUTHEAST MN PERHAPS NEEDING INCLUSION AS WELL. AN INCREASING MID CLOUD DECK TOWARDS 12Z ACCOMPANYING THE WARM ADVECTION SHOULD ALSO HELP TO GIVE TEMPERATURES A BOOST. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 206 AM CST MON DEC 1 2014 FOCUS/ATTENTION FOR THE TUESDAY THROUGH WEDNESDAY TIME PERIOD REMAINS ON THE CURRENT UPPER TROUGH ALONG THE BRITISH COLUMBIA COAST. MODEL AGREEMENT REMAINS GOOD BRINGING THIS TROUGH ACROSS THE NORTHERN PLAINS TUESDAY...ITS AXIS OVER THE FORECAST AREA BY 12Z WEDNESDAY...AND OFF INTO THE EASTERN GREAT LAKES BY 00Z THU. AHEAD OF THE TROUGH FOR TUESDAY...A BRISK SOUTHWEST WIND WILL HELP TO BOOST 925MB TEMPS UP TO -5 TO -8C BY 00Z. THESE READINGS COMBINED WITH SOME SUN FILTERED THROUGH PERIODS OF MID/HIGH CLOUDS SUPPORT HIGHS IN THE 20S TO LOW 30S...WARMEST IN FAR SOUTHWEST WI AND RIVER VALLEYS WHERE SNOW COVER IS LIMITED. AS WE HEAD INTO THE LATE AFTERNOON AND EVENING HOURS...MODEL DISAGREEMENT BEGINS TO SHOW UP NORTH OF I-90 IN THE PRECIPITATION DEPARTMENT. THE 01.00Z NAM AND REGIONAL CANADIAN MODELS WANT TO PRODUCE SOME LIGHT SNOW... ESPECIALLY NORTH OF I-94. THE 01.00Z GFS AND FOR THE MOST PART THE 01.00Z ECMWF ARE DRY. BOTH MODEL GROUPS DEPICT WEAK ISENTROPIC LIFTING IN THE 900-600MB LAYER...BUT THE DIFFERENCE IS THAT THE NAM/REGIONAL CANADIAN HAVE MORE MOISTURE IN THE 900-700MB LAYER. HARD TO SAY AT THIS POINT WHAT THAT LAYER MOISTURE WILL LOOK LIKE SO MAINTAINED SOME LOW CHANCES OF PRECIPITATION NORTH OF I-94 FOR THE LATE AFTERNOON/EVENING HOURS. ANY SNOW SHOULD PUSH OFF TO THE EAST AFTER 06Z AS THE UPPER TROUGH AXIS MOVES IN AND A COLD FRONT PASSES THROUGH. THIS COLD FRONT WILL USHER IN SLIGHTLY COOLER AIR FOR WEDNESDAY AS 925MB TEMPS FALL TO -6 TO -10C. THERE SHOULD BE PLENTY OF SUN ON WEDNESDAY AS DRY AIR AND SUBSIDENCE MOVES IN BEHIND THE UPPER TROUGH...SO HIGHS ARE EXPECTED TO BE NEAR OR JUST A LITTLE COOLER THAN TUESDAY. FROM WEDNESDAY NIGHT THROUGH FRIDAY...THE UPPER FLOW IS PROGGED TO BECOME MORE ZONAL...WITH NORTHERN AND SOUTHERN STREAMS BECOMING MORE EVIDENT. THE NORTHERN STREAM LOOKS TO TRACK ACROSS SOUTHERN CANADA WHILE THE SOUTHERN STREAM BECOMES POSITIONED ACROSS THE SOUTHERN U.S.. THE IMPACT TO THE FORECAST AREA FROM THE POSITIONS OF THESE STREAMS IS A WARMING TREND AS PACIFIC AIR FLOWS EASTWARD...AS WELL AS DRY CONDITIONS WITH THE SOUTHERN STREAMING BLOCKING GULF MOISTURE. THERE IS ONE SMALL OPPORTUNITY DURING THIS PERIOD TO PICK UP SOME LIGHT SNOW AND THAT IS ON THURSDAY FROM THE 30.00Z/12Z AND 01.00Z ECMWF. THE ECMWF SUGGESTS A DECENT SHORTWAVE AS WELL AS BAND OF MID LEVEL FRONTOGENESIS AND MOISTURE TO HELP PRODUCE THE SNOW. HOWEVER...ALL OTHER GUIDANCE IS DRY...SUGGESTING THE DRY AIR THAT CAME IN ON WEDNESDAY WILL BE ENOUGH TO ABSORB ANY SNOW FALLING OUT OF THE MID CLOUD. CONSIDERED LEAVING THURSDAY DRY...BUT THE ECMWF CONTINUITY IS CONCERNING. THEREFORE...HAVE ADDED A 20 PERCENT CHANCE TO LOCATIONS NORTH OF I-90. THURSDAYS HIGHS MAY NOT BE MUCH DIFFERENT THAN WEDNESDAY DUE TO CLOUDS MOVING IN AND WARM ADVECTION JUST BEGINNING TO GET IN EARNEST. BETTER SHOT FOR WARMER CONDITIONS COMES FRIDAY AS 925MB TEMPS REACH -2 TO -4C. THOSE READINGS COULD SUPPORT 30S TO LOW 40S...BUT IT APPEARS WE WILL BE BATTLING LOW STRATUS PER ECMWF/GFS 925MB RH FIELDS NEAR SATURATION...THUS HAVE TEMPERED HIGHS SOME. HEADING INTO THE WEEKEND...THE SPLIT FLOW REGIME CONTINUES...WITH HIGH PRESSURE PROGGED AT THE SURFACE. THUS...WE SHOULD SEE A CONTINUATION OF DRY CONDITIONS. SOME DISCREPANCIES EXIST ON HOW WARM THE WEEKEND WILL BE...AND IN PARTICULAR SATURDAY WHERE THE ECMWF DRIVES A LITTLE BIT MORE COLD AIR INTO THE REGION COMPARED TO THE GFS. NEVERTHELESS...READINGS SHOULD BE CLOSE TO NORMAL ON SATURDAY WITH MORE CONFIDENCE OF ABOVE NORMAL ON SUNDAY AS 925MB TEMPS THEN CLIMB TO AT LEAST 0C...IF NOT SLIGHTLY HIGHER. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 515 AM CST MON DEC 1 2014 GOOD VFR CONDITIONS EXPECTED TODAY/TONIGHT AS COLD AND DRY CANADIAN/ ARCTIC HIGH PRESSURE DRIFTS ACROSS THE UPPER MIDWEST. NORTHWEST WINDS 8-12 KTS WILL GIVE WAY TO LIGHTER/VARIABLE WINDS THIS AFTERNOON AS THE CENTER OF THE HIGH DRIFTS ACROSS THE AREA. WINDS THEN SWING SOUTHEAST/SOUTH AND INCREASE TONIGHT AS THE HIGH MOVES EAST OF THE REGION AND THE PRESSURE GRADIENT OVER THE AREA TIGHTENS AHEAD OF THE NEXT LOW/TROUGH MOVES INTO THE NORTHERN PLAINS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...DAS SHORT TERM...AJ LONG TERM...AJ AVIATION...RRS