Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/17/14
AREA FORECAST DISCUSSION
NWS PUEBLO CO
330 PM MST SAT NOV 15 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 330 PM MST SAT NOV 15 2014
...WIDESPREAD SNOW TO IMPACT THE REGION TONIGHT...
COLD FRONT HAS ALREADY DROPPED THROUGH SOUTHEAST COLORADO THOUGH
CORE OF COLDER AIR IS STILL SITTING ACROSS NORTHEAST COLORADO AND
NORTHERN EL PASO COUNTY WHERE TEMPERATURES ARE IN THE TEENS (VS. THE
UPPER 20S AND 30S ACROSS THE REMAINDER OF THE SOUTHEAST PLAINS).
MAIN UPPER TROF IS CURRENTLY ACROSS WY/ID AND WILL CONTINUE DROPPING
SOUTHWARD INTO THE 4 CORNERS REGION TONIGHT. UPPER JET ACROSS CO
HAS LED TO SOME BANDED SNOW ACROSS NORTHEAST COLORADO...WITH SOME
PERIODIC LIGHT SNOW CONTINUING ACROSS THE NORTHERN PORTIONS OF
MONUMENT HILL WHERE MOST OF THE FORCING IS LIKELY DUE TO SHALLOW
OROGRAPHICS. SNOW ALSO CONTINUES ALONG THE CONTINENTAL
DIVIDE...THOUGH INTENSITIES HAVE LET UP QUITE A BIT FROM THIS
MORNING. THAT WILL BE CHANGING IN THE NEXT 6 HOURS THOUGH AS
DYNAMICS FROM THE UPPER TROF SHIFTS SOUTHWARD WITH TIME. BEST QG
FORCING APPEARS TO DROP THROUGH THE WESTERN AND SOUTHERN PORTIONS OF
THE FORECAST AREA. CHALLENGES STILL REVOLVE AROUND SNOW AMOUNTS.
MODELS APPEAR TO BE STRUGGLING THE MOST ACROSS THE PIKES PEAK
REGION...WITH GFS PREDICTING A HEALTHY 3-7 INCHES ACROSS THIS
REGION...WHILE NAM12 HAS MORE IN THE 1 TO 3 INCH RANGE. RAP IS
GOING ALONG WITH GFS...WHILE ECMWF AND OTHER HIGH RES MODELS
(ARW..NMM) AGREE MORE WITH THE NAM. SO HAVE TO HUNT FOR CLUES TO
SUGGEST WHERE TO PUT THE NORTHERN EDGE OF THE HEADLINE AREAS. GIVEN
THE TRACK OF THE UPPER FORCING IS FARTHER TO THE SOUTH...AND THE
BEST UPGLIDE OVER THE H7 FRONT SEEMS TO BE MORE ACROSS SOUTHERN
AREAS...HAVE LEFT PIKES PEAK AND EL PASO COUNTY OUT OF THE ADVISORY
AREA FOR NOW. SNOWFALL GRIDS WILL CARRY AROUND 2-5 INCHES WITH
SOUTHERN EL PASO COUNTY MORE IN THE 2 TO 3 INCH RANGE.
WHERE MODELS AGREE BETTER IS ACROSS THE SOUTHEAST MOUNTAINS AND
SOUTHERN I-25 CORRIDOR. HAVE EXPANDED THE ADVISORIES NORTHWARD AND
EASTWARD A TAD. PUEBLO COUNTY IS ALWAYS A CHALLENGE AS HEAVIER
AMOUNTS MAY END UP ACROSS SOUTHERN AND WESTERN PORTIONS OF THE
COUNTY WHILE NORTHEAST PORTIONS SEE MORE IN THE 1-3 INCH RANGE. ALL
THE MODELS SEEM TO HIT THE SOUTHERN SANGRES WITH THE HEAVIEST
AMOUNTS OF QPF...AND THIS LOOKS REASONABLE GIVEN THE TRACK OF THE
SYSTEM. THUS HAVE UPGRADED THE WINTER WEATHER ADVISORY TO A WARNING
FOR THE SOUTHERN SANGRES. HAVE ALSO ADDED EASTERN LAS ANIMAS COUNTY
TO THE ADVISORY WHERE THE NORTHERN SLOPES OF THE RATON WILL HAVE THE
BENEFIT OF SOME NORTHEAST OROGRAPHICS.
WILL HOLD ON TO THE WINTER STORM WARNINGS ALONG THE CONTINENTAL
DIVIDE. THESE AREAS SHOULD PICK UP ANOTHER 5 TO 10 INCHES OVERNIGHT
WITH THE HEAVIEST ACROSS SOUTHERN PORTIONS OF THE EASTERN SAN JUAN
MOUNTAINS.
A COUPLE OTHER CHALLENGING SPOTS INCLUDE THE SAN LUIS VALLEY WHERE
HIGH RES MODELS ARE NOT SHOWING MUCH SNOW. HAVE GONE WITH AROUND AN
INCH TO 1.5 ACROSS THE VALLEY FLOOR GIVEN THIS AREA WILL BE IN
BETTER PROXIMITY TO THE UPPER DYNAMICS. BEST CHANCE WILL COME IN
AFTER 10 PM FOR THIS AREA. BACA COUNTY IS THE FINAL CHALLENGE.
MODEL RUNS WERE SUGGESTING AROUND 2 TO 4 INCHES OUT THAT WAY...JUST
SHY OF ADVISORY CRITERIA...BUT LATEST NAM12 HAS COME IN HEAVIER...SO
THIS AREA MAY HAVE TO BE MONITORED CLOSELY IF THE HEAVIER SNOW BAND
SETS UP ACROSS THAT AREA.
HIGHLIGHTS WILL PARE OFF FROM NORTH TO SOUTH TOWARDS MORNING. MOST
OF THE SNOW WILL BE DONE BY 10Z UP NORTH...AND BY 13-16Z DOWN SOUTH.
MOSTLY SUNNY SKIES WILL RETURN BY MID DAY SUNDAY. TEMPERATURES
TONIGHT WILL DROP BACK DOWN INTO THE SINGLE DIGITS FOR MOST OF THE
SOUTHEAST PLAINS WHERE THE CORE OF THE COLDER AIR WILL SPREAD IN.
SOME SPOTS COULD DROP INTO THE NEGATIVE DIGITS UP NORTH IF CLEARING
CAN OCCUR EARLY ENOUGH. SAN LUIS VALLEY WILL HAVE THE BENEFIT OF
CLOUDS AND PRECIPITATION OVERNIGHT SO LOWS THERE MAY ONLY DROP INTO
THE TEENS. KEPT HIGH TEMPERATURES ON SUNDAY CLOSER TO THE COLDER
SIDE OF GUIDANCE. -KT
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 330 PM MST SAT NOV 15 2014
...A SLOW WARMING TREND...
A SLOW WARMING TREND TO AROUND MID NOVEMBER AVERAGES REMAINS IN THE
OFFING INTO THE MIDDLE OF THE UPCOMING WORK WEEK...AS COLD NORTH TO
NORTHWEST FLOW ALOFT ACROSS THE REGION SUNDAY NIGHT GIVES WAY TO
WARMER MORE WESTERLY FLOW BY WEDNESDAY. TEMPERATURES TO BE THE MAIN
CONCERN AND HEADACHE IN THE SHORT TERM...WITH HIGHS AND LOWS TO BE
INFLUENCED BY SNOW COVER. AT ANY RATE...HAVE GONE AT OR BELOW THE
COLDER SIDE OF GUIDANCE FOR SUNDAY NIGHT AND MONDAY...ESPECIALLY
ACROSS THE SOUTHEASTERN MTS AND PLAINS WITH LOWS IN THE SINGLE
DIGITS ABOVE AND BELOW ZERO AND HIGHS MAINLY IN THE 20S. INDUCED LEE
TROUGHING AHEAD OF A SHORT WAVE TRANSLATING ACROSS THE NORTHERN
ROCKIES SHOULD KEEP LOWS SLIGHTLY WARMER ACROSS THE EASTERN SLOPES
MONDAY NIGHT AND COULD BOOST HIGHS INTO THE 30S TO LOWER 40S
ACROSS THE LOWER ELEVATIONS ON TUESDAY.
BUILDING UPPER RIDGE ACROSS THE GREAT BASIN TUESDAY NIGHT FLATTENS
ACROSS THE STATE THROUGH WEDNESDAY NIGHT AS MINOR WAVES TRANSLATE
EAST ACROSS THE GREAT BASIN AND ROCKIES...WITH THE DOWNSLOPE FLOW
OWNING TO THE EXPECTED WARMING TEMPERATURES AND BRINGING CHANCES
OF LIGHT SNOWFALL TO THE HIGHER TERRAIN...MAINLY ALONG AND WEST OF
THE CONTDVD THURSDAY AND FRIDAY. LATEST MODELS ARE SHOWING A
STRONGER SYSTEM MOVING ACROSS THE GREAT BASIN FRIDAY AND ACROSS
THE ROCKIES ON SATURDAY...THOUGH BOTH THE GFS AND EC HAVE SHOWN
RUN TO RUN INCONSISTENCIES ON ITS TIMING AND STRENGTH. FOR
NOW...HAVE KEPT ANY PRECIPITATION CHANCES CONFINED TO THE HIGHER
TERRAIN FRIDAY NIGHT AND SATURDAY WITH TEMPERATURES AROUND
SEASONAL AVERAGES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 330 PM MST SAT NOV 15 2014
EXPECT DETERIORATING CONDITIONS THROUGH THE EVENING WITH
CIGS DROPPING INTO THE IFR CATEGORY AT KCOS AND KPUB BY 00Z AS SNOW
DEVELOPS AND SPREAD OFF THE MOUNTAINS. BOTH TERMINALS COULD SEE
AROUND 2 TO 2.5 INCHES OF SNOW. SNOW SHOULD DIMINISH AFTER 10Z FOR
BOTH TERMINALS WITH CIGS BREAKING BY 15Z. VFR CONDITIONS WILL
CONTINUE THROUGH SUNDAY. KALS WILL SEE A LITTLE LATER START TO THE
SNOW...WITH SNOW SPREADING IN AFTER 05Z...AND CONTINUING THROUGH
12Z. CIGS MAY DROP INTO THE IFR CATEGORY AT TIMES OVERNIGHT.
WIDESPREAD MTN OBSCURATIONS CAN BE EXPECTED TONIGHT WHICH WILL
DECREASE FROM NORTH TO SOUTH SUNDAY MORNING.
MEANWHILE...GUSTY NORTH WINDS WILL CONTINUE THROUGH THE EVENING
ACROSS THE PLAINS BEFORE DIMINISHING OVERNIGHT. KALS WILL SEE GUSTY
WEST WINDS...SHIFTING AROUND TO THE NORTH AFTER 08-09Z AS THE SYSTEM
MOVES ACROSS. WINDS ON SUNDAY WILL BE LIGHTER AT ALL THREE TAF
SITES. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 AM MST SUNDAY FOR COZ072-073-079-
080-087-088-094.
WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR COZ077-078-083-
086.
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066.
WINTER STORM WARNING UNTIL 9 AM MST SUNDAY FOR COZ074-075.
WINTER STORM WARNING UNTIL 9 AM MST SUNDAY FOR COZ068.
&&
$$
SHORT TERM...KT
LONG TERM...MW
AVIATION...KT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1050 AM MST SAT NOV 15 2014
.UPDATE...
ISSUED AT 1003 AM MST SAT NOV 15 2014
BASED ON LATEST SAT AND MSAS SFC PRESSURE RISES...FRONT ALREADY
PUSHING THROUGH EL PASO COUNTY. IRONICALLY THE MIXING HAS BROUGHT
SOME WARMING WITH LOCATIONS FINALLY HITTING ABOVE FREEZING THE
FREEZING MARK...BUT TEMPERATURES ARE IN THE TEENS BEHIND THE
FRONT SO EXPECT ANOTHER QUICK DROP IN TEMPERATURES THROUGH THE
AFTERNOON ACROSS SE CO. HIGHS HAVE ALREADY LIKELY BEEN REACHED IN
EL PASO COUNTY WITH FALLING TEMPERATURES EXPECTED THROUGH THE
REMAINDER OF THE DAY. MODELS CONTINUING TO STRUGGLE WITH TIMING OF
PRECIPITATION AS IT IS ALREADY SNOWING UP IN NE COLORADO WHICH
MODELS ARE NOT HANDLING WELL. SPED UP THE TIMING OF SNOW IN THE
GRIDS. EXPECT LIGHT SNOW TO START BY LATE MORNING ACROSS MONUMENT
HILL...WITH HEAVIER SNOW HOLDING OFF UNTIL 22Z ACROSS NORTHERN
PORTIONS OF THE AREA...THEN RAPIDLY SPREADING SOUTHWARD THROUGH
00Z AS FORCING FROM THE UPPER TROF APPROACHES. -KT
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM MST SAT NOV 15 2014
...MORE SNOW AND ARCTIC AIR ON THE WAY...
CURRENTLY...
THE LEADING EDGE OF THE NEXT ARCTIC INTRUSION WAS ALONG THE CO/WY
BORDER AND IT WAS HEADING SOUTH. CLOSER TO HOME...TEMPERATURES AT 3
AM VARIED CONSIDERABLY ACROSS THE PLAINS...AS ELEVATIONS GENERALLY
ABOVE 6000 FEET WERE IN THE RELATIVELY WARMER AIR (30S AND 40S)
WHILE AREAS BELOW 6000 WERE IN THE TEENS AND 20S. IN THE MTNS AND
VALLEYS...IT WAS RELATIVELY WARM WITH TEMPS IN THE 20S AND 30S.
RADAR...OBS AND WEB CAMS INDICATED THAT SNOW STILL OCCURRING OVER
THE CONTDVD.
TODAY...
WEATHER WILL BE QUITE ACTIVE DURING THE NEXT 24. HRRR INDICATES THAT
THE LEADING EDGE OF THE ARCTIC AIR WILL MOVE INTO EL PASO COUNTY
AROUND 9-10 AM AND WILL PROGRESS SOUTH...REACHING THE NEW MEXICO
BORDER BY 3 PM. LIKEWISE...MAX TEMPS TODAY WILL LIKELY OCCUR THIS
MORNING ACROSS THE PIKES PEAK REGION AND MIDDAY ACROSS THE REST OF
THE REGION. TEMPS WILL QUICKLY FALL AFTER THE ARCTIC FRONT GOES BY.
AS FOR PRECIP...IN THE MTNS...STEADY SNOW...SOME HEAVY...WILL
CONTINUE ACROSS THE CENTRAL MTNS ALL DAY TODAY. SNOW ACROSS THE SAN
JUANS WILL DECREASE LATER THIS MORNING BUT WILL RAMP UP ONCE AGAIN
BY MID AFTERNOON.
PRECIP ON THE PLAINS WILL GENERALLY DEVELOP ACROSS THE PIKES PEAK
REGION SHORTLY AFTER NOON AND WILL PICK UP AS THE AFTERNOON
PROGRESSES. STEADY SNOW WILL LIKELY BE ONGOING BY LATE AFTERNOON
ACROSS EL PASO COUNTY AND TRAVEL WILL ONCE AGAIN BECOME DIFFICULT
ACROSS THIS REGION. WINDS WILL LIKELY BE A BIT GUSTY SO AREAS OF
BLOWING SNOW WILL OCCUR.
BY LATE AFTERNOON THE SNOW WILL DEVELOP FARTHER SOUTH DOWN THE I-25
CORRIDOR AND EASTERN MTN REGION. OTHERWISE...THE REST OF THE PLAINS
WILL LIKELY REMAIN DRY.
TONIGHT...
MAIN CONCERN DURING THIS PERIOD IS THE SPANISH PEAKS/RATON MESA/WET
MTNS REGION AS ALL GUIDANCE IS SHOWING PRETTY HEALTHY QPF BULLSEYES
OVER THIS REGION. FOR NOW I HAVE ISSUED A WINTER WEATHER ADVISORY
FOR THIS REGION WITH THE AREA LIKELY RECEIVING 3-6 INCHES OF SNOW AT
THE LOWER ELEVATIONS OF LAS ANIMAS AND HUERFANO COUNTIES WHILE HIGHER
ELEVATIONS WILL LIKELY RECEIVE 4 TO 10 INCHES OF SNOW. IT IS
POSSIBLE THAT THESE VALUES MAY BE ON THE LOW SIDE...ESPECIALLY IF
GUIDANCE DOES VERIFY. WILL ALLOW LATER SHIFT TO REANALYZE AND
UPGRADE TO WARNING STATUS IF LATER SIMULATIONS SHOW LARGE QPF VALUES
OVER AFOREMENTIONED REGION.
FOR THE REST OF THE PLAINS...EL PASO COUNTY SHOULD GENERALLY RECEIVE
ABOUT 2-4" OF SNOW WITH THIS EVENT WITH 2-6 IN TELLER COUNTY AND
PIKES PEAK. PUEBLO/FREMONT COUNTIES WILL LIKELY RECEIVE ANYWHERE
FROM BETWEEN 2 AND 5 INCHES. OVER THE FAR EAST PLAINS...1 TO 2
INCHES WILL BE POSSIBLE.
THE MOUNTAINS WILL CONTINUE TO SEE SNOW...HOWEVER THE SNOW WILL END
FROM S TO N ACROSS THE C MTNS LATER TONIGHT. OVERALL ANOTHER 6 TO
12 INCHES OF SNOW IS LIKELY OVER THE CONTDVD REGION
TEMPS TONIGHT WILL BE COLD ONCE AGAIN ACROSS THE ENTIRE REGION.
SINGLE DIGITS WILL OCCUR ACROSS NEARLY ALL OF THE REGION EXCEPT
TEENS MAINLY IN THE SAN LUIS VALLEY. /HODANISH
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 412 AM MST SAT NOV 15 2014
...COLD SUNDAY THEN GRADUAL WARMING...
SNOW WILL LINGER ALONG THE SOUTHERN BORDER AREAS EARLY
SUNDAY...BUT SHOULD MOSTLY END BY NOON AS PROGRESSIVE
SHORTWAVE MOVES ON THROUGH. NEW SHOT OF ARCTIC AIR WILL
BRING ONE MORE REALLY COLD DAY SUNDAY BUT THEN THINGS WILL
START TO WARM UP AND DRY OUT FOR MOST OF THE UPCOMING WEEK.
THE WARM UP MAY START A LITTLE SLOW ON MONDAY AS SNOW COVER AND
LIGHT PRESSURE GRADIENTS WILL TEND TO KEEP SURFACE INVERSIONS IN
PLACE THROUGH THE DAY. BY TUESDAY...IT LOOKS LIKE WE SHOULD SEE A
LITTLE BETTER MIXING AS DOWNSLOPE PRESSURE GRADIENTS DEVELOP. THIS
SHOULD HELP BRING CHINOOK BREEZES OFF THE MOUNTAINS TO START
WARMING THE AIR.
COULD BE A LITTLE SET BACK WEDNESDAY AS THE MODELS ARE SHOWING A
WEAK SURFACE HIGH DROPPING THROUGH THE PLAINS THIS DAY. THIS COULD
REESTABLISH INVERSIONS IF THERE IS ENOUGH COOLING WITH THE HIGH
AND IF THERE IS ANY SNOW COVER REMAINING.
THURSDAY AND ESPECIALLY FRIDAY...IT LOOKS LIKE SOME WEAK ENERGY
FROM THE PACIFIC WILL START MOVING BACK INTO THE REGION. THIS
ENERGY COULD SPREAD SOME SNOW SHOWERS INTO THE CONTINENTAL DIVIDE
THURSDAY...AND EAST TO THE REST OF THE MOUNTAINS AND PIKES PEAK
REGION ON FRIDAY. THE APPROACHING ENERGY DOESN`T LOOK STRONG AT
THIS POINT SO FORECAST CONFIDENCE IS LOW AT THIS TIME. TEMPERATURES
WILL LIKELY REMAIN MILD THURSDAY...BUT THEN START TO COOL ON
FRIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1016 AM MST SAT NOV 15 2014
FRONT ALREADY MOVING INTO NORTHERN PUEBLO COUNTY AS OF 1745Z.
EXPECT IT TO HIT THE KPUB TAF SITE WITHIN THE NEXT HOUR. WINDS
BEHIND THE FRONT WILL BE FROM THE NORTHEAST AT 15-30 KTS THROUGH
THE AFTERNOON. IFR STRATUS IS ALREADY BANKED UP ACROSS NORTHERN EL
PASO COUNTY...AND EXPECTED TO SPREAD SOUTHWARD AND FILL IN
AGAINST THE MOUNTAINS THROUGH THE AFTERNOON. TIMING OF SNOWFALL
IS A CHALLENGE AS FORECAST MODELS NOT HANDLING IT WELL WHERE SNOW
IS ALREADY FALLING ACROSS NORTHEAST CO. EXPECT SOME LIGHT SNOW TO
BEGIN IN KCOS AROUND 22Z...AND IN KPUB BY 23Z. HEAVIER SNOW WILL
COME IN AFTER 00Z AS A BAND DEVELOPS WITH THE INCOMING SYSTEM AND
SPREADS SOUTHWARD. IFR TO LIFR CONDITIONS CAN BE EXPECTED
OVERNIGHT. KALS WILL SEE A LATER START TO SNOW...PROBABLY AROUND
05Z...BUT SHOULD SEE IFR CONDITIONS DEVELOP OVERNIGHT WITH SNOW.
ALL THREE TERMINALS SHOULD EXPECT A COUPLE INCHES...WITH HEAVIER
AMOUNTS NEAR THE MOUNTAINS. RAPIDLY IMPROVING CONDITIONS WILL SET
IN EARLY SUNDAY MORNING WITH ANY LINGERING VFR STRATUS CLEARED
OUT BY 15Z. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 9 AM MST
SUNDAY FOR COZ072>075-079-080-087-088.
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066-
068.
&&
$$
UPDATE...KT
SHORT TERM...HODANISH
LONG TERM...LW
AVIATION...KT
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1015 AM MST SAT NOV 15 2014
.UPDATE...
ISSUED AT 954 AM MST SAT NOV 15 2014
RADAR SHOWS SNOW BANDS INCREASING WHILE CLOUD TOPS ARE ALSO
COOLING ACROSS THE REGION. AIRMASS IS POTENTIALLY UNSTABLE PER 12Z
GRAND JUNCTION SOUNDING AND NOSE OF FIRST UPPER LEVEL SPEED MAX IS
AIDING UPPER LEVEL DIVERGENCE. CONVECTIVE SHOWERS EVIDENCED ON THE
WESTERN SLOPE RADAR WHILE BANDS OF HEAVIER SNOW HAVE ALREADY MOVED
ACROSS THE NORTHERN PLAINS INCLUDING FORT COLLINS WHICH PICKED UP
A QUICK ONE HALF TO ONE INCH OF SNOW WHEN A BAND MOVED ACROSS.
FIRST SPEED MAX WILL PASS OFF TO THE NORTH LATER THIS MORNING
WHILE NEXT JET MAX WILL PLOW INTO WESTERN COLORADO LATE THIS
AFTERNOON/EVENING. LIFT ASSOCIATED WITH THIS NEXT SURGE SHOULD
BRING ANOTHER INCREASE IN SNOW MAINLY ALONG AND SOUTH OF THE I-70
CORRIDOR. AS A RESULT...WILL UPGRADE THE ADVISORY IN THE I-70
CORRIDOR OF THE MOUNTAINS INCLUDING SUMMIT COUNTY...ZONE 34...TO
A WINTER STORM WARNING THROUGH MIDNIGHT. OTHER MAIN CHANGES WERE
TO INCREASE POPS AND SNOW AMOUNTS ON THE PLAINS PER LATEST
TRENDS...AND ALSO DELAY ENDING OF SNOW MAINLY FROM DENVER AND
LIMON SOUTHWARD THIS EVENING AS NEXT BATCH OF LIFT SEEN IN THE Q-G
FIELDS PROVIDE AT LEAST WEAK UPPER LEVEL LIFT. TEMPERATURE
FORECAST ON TRACK WITH FALLING TEMPS IN ARCTIC AIRMASS THROUGH THE
REST OF THE DAY AND BELOW ZERO READINGS MUCH OF THE PLAINS
TONIGHT.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 450 AM MST SAT NOV 15 2014
TWO WEATHER FEATURES TO CONTEND WITH THIS MORNING. FIRST IS THE
ARCTIC FRONT SLIPPING SOUTH THROUGH WELD AND WASHINGTON COUNTIES
AT THE MOMENT. A PRE-FRONTAL WIND SHIFT HAS ALREADY SWEPT THROUGH
THE DENVER METRO AREA...BUT THE COLDER AIR AND LOWER CLOUDS ARE
OBSERVED NORTH OF THE MAIN FRONTAL BNDRY. AT PRESENT SPEED COULD
SEE THE FRONT INTO THE GREATER DENVER METRO AREA WITH THE NEXT30
MINS OR SO. PRESSURE RISES BEHIND THIS FRONT NOTHING LIKE THOSE
PRESENT BEHIND THE STRONGER ARCTIC FRONT LAST MONDAY.
NEVERTHELESS...SHOULD SEE TEMPERATURES SLIPPING ON THE PLAINS
THROUGH THE MORNING WITH GUSTY N-NELY. GOOD BET TEMPERATURES HAVE
ALREADY MAXED OUT FOR TODAY ON THE PLAINS. GUIDANCE INDICATING
SINGLE DIGIT TEMPERATURES BY THIS AFTERNOON.
FURTHERMORE...SNOWFALL EAST OFF THE MTNS IS STILL UP IN
WYOMING...BUT WITHIN NEXT FEW HOURS SHOULD SEE A BAND OF LIGHT
SNOW MAKING ITS WAY SOUTHWARD ACRS THE CWA ACCORDING TO THE HRRR
AND RAP. ACCUMULATION RATES SHOULD REMAIN ON THE LIGHT
SIDE...GENERALLY UNDER A QUARTER INCH PER HOUR THROUGH MIDDAY.
HOWEVER MODELS SHOW A BAND OF HEAVIER SNOW DEVELOPING ALONG THE
I-70 CORRIDOR DURING THE MID TO LATE AFTERNOON HOURS WITH SNOWFALL
RATES AROUND 1/2 TO 3/4 INCH PER HOUR. SHOULD SEE PRECIP COMING
TO AN END FROM NORTH TO SOUTH DURING THE EVENING HOURS AS LIFT AND
INSTABILITY SHIFT SOUTH OF THE AREA.
IN THE HIGH COUNTRY...AN INFLUX OF PACIFIC MOISTURE ON THE NOSE OF
A 110+ KT JET WILL RESULT IN A STEADY INFLUX OF SNOWFALL ACROSS
THE HIGH COUNTRY THROUGH THE MORNING. WEST FACING ASPECTS IN BEST
POSITION TO PICK UP GREATEST SNOW AMOUNTS OVER THE NEXT 18 HOURS.
WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW NOW IN EFFECT
FOR MTN ZONES. MTN VALLEYS ZONES 30 AND 32 HAVE BEEN ADDED TO THE
ADVSY. 5-12 INCH ACCUMS EXPECTED IN MTN ZONES...WITH 3-7 INCH
TOTALS ON THE VALLEY FLOORS. INCREASING WEST WINDS WITH ARRIVAL
OF THE JET LATER THIS MORNING WILL LIKELY PRODUCE BLOWING AND
DRIFTING SNOW IN OPEN AREAS IN THE HIGH COUNTRY MAKING TRAVEL
DIFFICULT IF NOT HAZARDOUS FOR A TIME THIS AFTERNOON.
JET...MOISTURE AND DYNAMICS ARE FORECAST TO MIGRATE SOUTH AND EAST
OF THE AREA THIS EVENING PUTTING A GRADUAL END TO SNOWFALL AND
WINDS STARTING IN THE NORTHERN AREAS. CLEARING SKIES LATE TONIGHT
WILL RESULT IN BITTER OVERNIGHT LOWS AND POSSIBLY SOME DENSE FOG
ON THE PLAINS BEFORE MORNING.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 450 AM MST SAT NOV 15 2014
THE UPPER LEVEL TROF AXIS WILL SAG SOUTHWARD OVER SOUTHERN
COLORADO SUNDAY MORNING WITH DRYING AIRMASS. HOWEVER WILL STILL
HAVE RATHER COLD TEMPERATURES DURING THE DAY SUNDAY WITH FRESH
SNOW COVER AND LINGERING LOW LEVEL INVERSIONS. BY SUNDAY
AFTERNOON AND EVENING AN UPPER LEVEL TROF SWEEPS ACROSS THE
NORTHERN HIGH PLAINS WITH SOME REFLECTION AT THE SURFACE OVER FAR
NORTHEAST COLORADO. STILL REMAINS A SUBSIDENT AIRMASS BUT A MID
LEVEL DECK OF CLOUDS EXPECTED. WILL KEEP CONDITIONS DRY FOR NOW
BUT GUSTY NORTHWEST WINDS OVER THE PLAINS.
MUCH OF NEXT WEEK THROUGH WEDNESDAY WILL BE CHARACTERIZED WITH A
STRONG NORTHWEST FLOW PATTERN WITH HIGH AMPLITUDE RIDGING ALONG
WEST COAST AND STRONG LOW OVER GREAT LAKES REGION. THERE WILL BE A
SLOW MODERATION OF TEMPERATURES WHILE GUSTY WINDS CONTINUE AT
TIMES OVER THE HIGH MOUNTAINS. COULD SEE SOME GUSTS UP TO 50 MPH
OVER THE MOUNTAIN PASSES.
BY THURSDAY AND FRIDAY...SOME PACIFIC MOISTURE BEGINS TO STREAM
INTO THE MOUNTAINS WITH A WEAK DISTURBANCE. WILL HAVE LOW POPS IN
FOR NOW. FOR LOWER ELEVATIONS...GENERALLY MILD WITH READINGS IN
THE 40S ALONG WITH DRY CONDITIONS.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z SUNDAY MORNING)
ISSUED AT 954 AM MST SAT NOV 15 2014
LIGHT SNOW AND IFR/MVFR CEILINGS/VSBYS OVER HAVE OVERSPREAD THE
FRONT RANGE AIRPORTS THIS MORNING. THESE CONDITIONS WILL CONTINUE
THROUGH THE AFTERNOON HOURS ALTHOUGH A COUPLE HEAVIER SNOW BANDS
COULD DROP VSBYS TO 1/4-1/2SM FOR A 30-45 MINUTE PERIOD. MAIN
CHANGE WAS TO DELAY THE ENDING OF SNOW AS NEXT UPPER LEVEL
DISTURBANCE COULD VERY WELL KEEP SNOW IN THE FORECAST TIL AROUND
06Z/07Z. LATEST SHORT RANGE RAP AND HRRR ALSO POINT TO THIS. TOTAL
SNOW ACCUMULATIONS 1-3 INCHES EXPECTED.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 8 PM MST THIS EVENING FOR
COZ030>033.
WINTER STORM WARNING UNTIL MIDNIGHT MST TONIGHT FOR COZ034.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...BAKER
LONG TERM...ENTREKIN
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1013 AM MST SAT NOV 15 2014
.UPDATE...
ISSUED AT 1003 AM MST SAT NOV 15 2014
BASED ON LATEST SAT AND MSAS SFC PRESSURE RISES...FRONT ALREADY
PUSHING THROUGH EL PASO COUNTY. IRONICALLY THE MIXING HAS BROUGHT
SOME WARMING WITH LOCATIONS FINALLY HITTING ABOVE FREEZING THE
FREEZING MARK...BUT TEMPERATURES ARE IN THE TEENS BEHIND THE
FRONT SO EXPECT ANOTHER QUICK DROP IN TEMPERATURES THROUGH THE
AFTERNOON ACROSS SE CO. HIGHS HAVE ALREADY LIKELY BEEN REACHED IN
EL PASO COUNTY WITH FALLING TEMPERATURES EXPECTED THROUGH THE
REMAINDER OF THE DAY. MODELS CONTINUING TO STRUGGLE WITH TIMING OF
PRECIPITATION AS IT IS ALREADY SNOWING UP IN NE COLORADO WHICH
MODELS ARE NOT HANDLING WELL. SPED UP THE TIMING OF SNOW IN THE
GRIDS. EXPECT LIGHT SNOW TO START BY LATE MORNING ACROSS MONUMENT
HILL...WITH HEAVIER SNOW HOLDING OFF UNTIL 22Z ACROSS NORTHERN
PORTIONS OF THE AREA...THEN RAPIDLY SPREADING SOUTHWARD THROUGH
00Z AS FORCING FROM THE UPPER TROF APPROACHES. -KT
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM MST SAT NOV 15 2014
...MORE SNOW AND ARCTIC AIR ON THE WAY...
CURRENTLY...
THE LEADING EDGE OF THE NEXT ARCTIC INTRUSION WAS ALONG THE CO/WY
BORDER AND IT WAS HEADING SOUTH. CLOSER TO HOME...TEMPERATURES AT 3
AM VARIED CONSIDERABLY ACROSS THE PLAINS...AS ELEVATIONS GENERALLY
ABOVE 6000 FEET WERE IN THE RELATIVELY WARMER AIR (30S AND 40S)
WHILE AREAS BELOW 6000 WERE IN THE TEENS AND 20S. IN THE MTNS AND
VALLEYS...IT WAS RELATIVELY WARM WITH TEMPS IN THE 20S AND 30S.
RADAR...OBS AND WEB CAMS INDICATED THAT SNOW STILL OCCURRING OVER
THE CONTDVD.
TODAY...
WEATHER WILL BE QUITE ACTIVE DURING THE NEXT 24. HRRR INDICATES THAT
THE LEADING EDGE OF THE ARCTIC AIR WILL MOVE INTO EL PASO COUNTY
AROUND 9-10 AM AND WILL PROGRESS SOUTH...REACHING THE NEW MEXICO
BORDER BY 3 PM. LIKEWISE...MAX TEMPS TODAY WILL LIKELY OCCUR THIS
MORNING ACROSS THE PIKES PEAK REGION AND MIDDAY ACROSS THE REST OF
THE REGION. TEMPS WILL QUICKLY FALL AFTER THE ARCTIC FRONT GOES BY.
AS FOR PRECIP...IN THE MTNS...STEADY SNOW...SOME HEAVY...WILL
CONTINUE ACROSS THE CENTRAL MTNS ALL DAY TODAY. SNOW ACROSS THE SAN
JUANS WILL DECREASE LATER THIS MORNING BUT WILL RAMP UP ONCE AGAIN
BY MID AFTERNOON.
PRECIP ON THE PLAINS WILL GENERALLY DEVELOP ACROSS THE PIKES PEAK
REGION SHORTLY AFTER NOON AND WILL PICK UP AS THE AFTERNOON
PROGRESSES. STEADY SNOW WILL LIKELY BE ONGOING BY LATE AFTERNOON
ACROSS EL PASO COUNTY AND TRAVEL WILL ONCE AGAIN BECOME DIFFICULT
ACROSS THIS REGION. WINDS WILL LIKELY BE A BIT GUSTY SO AREAS OF
BLOWING SNOW WILL OCCUR.
BY LATE AFTERNOON THE SNOW WILL DEVELOP FARTHER SOUTH DOWN THE I-25
CORRIDOR AND EASTERN MTN REGION. OTHERWISE...THE REST OF THE PLAINS
WILL LIKELY REMAIN DRY.
TONIGHT...
MAIN CONCERN DURING THIS PERIOD IS THE SPANISH PEAKS/RATON MESA/WET
MTNS REGION AS ALL GUIDANCE IS SHOWING PRETTY HEALTHY QPF BULLSEYES
OVER THIS REGION. FOR NOW I HAVE ISSUED A WINTER WEATHER ADVISORY
FOR THIS REGION WITH THE AREA LIKELY RECEIVING 3-6 INCHES OF SNOW AT
THE LOWER ELEVATIONS OF LAS ANIMAS AND HUERFANO COUNTIES WHILE HIGHER
ELEVATIONS WILL LIKELY RECEIVE 4 TO 10 INCHES OF SNOW. IT IS
POSSIBLE THAT THESE VALUES MAY BE ON THE LOW SIDE...ESPECIALLY IF
GUIDANCE DOES VERIFY. WILL ALLOW LATER SHIFT TO REANALYZE AND
UPGRADE TO WARNING STATUS IF LATER SIMULATIONS SHOW LARGE QPF VALUES
OVER AFOREMENTIONED REGION.
FOR THE REST OF THE PLAINS...EL PASO COUNTY SHOULD GENERALLY RECEIVE
ABOUT 2-4" OF SNOW WITH THIS EVENT WITH 2-6 IN TELLER COUNTY AND
PIKES PEAK. PUEBLO/FREMONT COUNTIES WILL LIKELY RECEIVE ANYWHERE
FROM BETWEEN 2 AND 5 INCHES. OVER THE FAR EAST PLAINS...1 TO 2
INCHES WILL BE POSSIBLE.
THE MOUNTAINS WILL CONTINUE TO SEE SNOW...HOWEVER THE SNOW WILL END
FROM S TO N ACROSS THE C MTNS LATER TONIGHT. OVERALL ANOTHER 6 TO
12 INCHES OF SNOW IS LIKELY OVER THE CONTDVD REGION
TEMPS TONIGHT WILL BE COLD ONCE AGAIN ACROSS THE ENTIRE REGION.
SINGLE DIGITS WILL OCCUR ACROSS NEARLY ALL OF THE REGION EXCEPT
TEENS MAINLY IN THE SAN LUIS VALLEY. /HODANISH
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 412 AM MST SAT NOV 15 2014
...COLD SUNDAY THEN GRADUAL WARMING...
SNOW WILL LINGER ALONG THE SOUTHERN BORDER AREAS EARLY
SUNDAY...BUT SHOULD MOSTLY END BY NOON AS PROGRESSIVE
SHORTWAVE MOVES ON THROUGH. NEW SHOT OF ARCTIC AIR WILL
BRING ONE MORE REALLY COLD DAY SUNDAY BUT THEN THINGS WILL
START TO WARM UP AND DRY OUT FOR MOST OF THE UPCOMING WEEK.
THE WARM UP MAY START A LITTLE SLOW ON MONDAY AS SNOW COVER AND
LIGHT PRESSURE GRADIENTS WILL TEND TO KEEP SURFACE INVERSIONS IN
PLACE THROUGH THE DAY. BY TUESDAY...IT LOOKS LIKE WE SHOULD SEE A
LITTLE BETTER MIXING AS DOWNSLOPE PRESSURE GRADIENTS DEVELOP. THIS
SHOULD HELP BRING CHINOOK BREEZES OFF THE MOUNTAINS TO START
WARMING THE AIR.
COULD BE A LITTLE SET BACK WEDNESDAY AS THE MODELS ARE SHOWING A
WEAK SURFACE HIGH DROPPING THROUGH THE PLAINS THIS DAY. THIS COULD
REESTABLISH INVERSIONS IF THERE IS ENOUGH COOLING WITH THE HIGH
AND IF THERE IS ANY SNOW COVER REMAINING.
THURSDAY AND ESPECIALLY FRIDAY...IT LOOKS LIKE SOME WEAK ENERGY
FROM THE PACIFIC WILL START MOVING BACK INTO THE REGION. THIS
ENERGY COULD SPREAD SOME SNOW SHOWERS INTO THE CONTINENTAL DIVIDE
THURSDAY...AND EAST TO THE REST OF THE MOUNTAINS AND PIKES PEAK
REGION ON FRIDAY. THE APPROACHING ENERGY DOESN`T LOOK STRONG AT
THIS POINT SO FORECAST CONFIDENCE IS LOW AT THIS TIME. TEMPERATURES
WILL LIKELY REMAIN MILD THURSDAY...BUT THEN START TO COOL ON
FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 412 AM MST SAT NOV 15 2014
KCOS...ARCTIC FRONT WILL CROSS KCOS AOA NOONTIME...18-19Z. WINDS
WILL SHIFT TO NORTH THAN NORTH-NORTHEAST AND BECOME GUSTY. COULD SEE
SOME SNOW SHOWERS BY MID AFTERNOON BUT EXPECT BRUNT OF IT WILL OCCUR
MORE TOWARDS SUNSET. LIFR CONDITIONS WILL BE POSSIBLE/LIKELY BETWEEN
00Z-09Z AS STEADY SNOW IS EXPECTED.
KPUB...ARCTIC FRONT WILL CROSS KPUB AOA 19-20Z WITH WINDS QUICKLY
SHIFTING TO THE NORTHEAST AND THEN EAST. PRECIP WILL LIKELY DEVELOP
AFTER SUNSET AND THERE IS A HIGH PROBABILITY THAT IT WILL SNOW...AND
IT IS EXPECTED TO ACCUMULATE TO 2-4 INCHES. LIFR CONDITIONS LIKELY
ONCE SNOW STARTS. IT WILL LAST THROUGH THE NIGHT ENDING AROUND
SUNRISE.
KALS...LOW CIGS THIS MORNING SHOULD BREAK UP ABOUT 1-2HRS AFTER
SUNRISE AS WEST WINDS INCREASE. VFR EXPECTED THROUGH THE REST OF THE
DAY WITH PRECIP DEVELOPING AFTER MIDNIGHT. SNOW WILL LIKELY
ACCUMULATE AT KALS WITH 1-2" ANTICIPATED. CIGS LIKELY WILL GO LIFR
AFTER MIDNIGHT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 9 AM MST
SUNDAY FOR COZ072>075-079-080-087-088.
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066-
068.
&&
$$
UPDATE...KT
SHORT TERM...HODANISH
LONG TERM...LW
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
444 AM MST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM MST SAT NOV 15 2014
...MORE SNOW AND ARCTIC AIR ON THE WAY...
CURRENTLY...
THE LEADING EDGE OF THE NEXT ARCTIC INTRUSION WAS ALONG THE CO/WY
BORDER AND IT WAS HEADING SOUTH. CLOSER TO HOME...TEMPERATURES AT 3
AM VARIED CONSIDERABLY ACROSS THE PLAINS...AS ELEVATIONS GENERALLY
ABOVE 6000 FEET WERE IN THE RELATIVELY WARMER AIR (30S AND 40S)
WHILE AREAS BELOW 6000 WERE IN THE TEENS AND 20S. IN THE MTNS AND
VALLEYS...IT WAS RELATIVELY WARM WITH TEMPS IN THE 20S AND 30S.
RADAR...OBS AND WEB CAMS INDICATED THAT SNOW STILL OCCURRING OVER
THE CONTDVD.
TODAY...
WEATHER WILL BE QUITE ACTIVE DURING THE NEXT 24. HRRR INDICATES THAT
THE LEADING EDGE OF THE ARCTIC AIR WILL MOVE INTO EL PASO COUNTY
AROUND 9-10 AM AND WILL PROGRESS SOUTH...REACHING THE NEW MEXICO
BORDER BY 3 PM. LIKEWISE...MAX TEMPS TODAY WILL LIKELY OCCUR THIS
MORNING ACROSS THE PIKES PEAK REGION AND MIDDAY ACROSS THE REST OF
THE REGION. TEMPS WILL QUICKLY FALL AFTER THE ARCTIC FRONT GOES BY.
AS FOR PRECIP...IN THE MTNS...STEADY SNOW...SOME HEAVY...WILL
CONTINUE ACROSS THE CENTRAL MTNS ALL DAY TODAY. SNOW ACROSS THE SAN
JUANS WILL DECREASE LATER THIS MORNING BUT WILL RAMP UP ONCE AGAIN
BY MID AFTERNOON.
PRECIP ON THE PLAINS WILL GENERALLY DEVELOP ACROSS THE PIKES PEAK
REGION SHORTLY AFTER NOON AND WILL PICK UP AS THE AFTERNOON
PROGRESSES. STEADY SNOW WILL LIKELY BE ONGOING BY LATE AFTERNOON
ACROSS EL PASO COUNTY AND TRAVEL WILL ONCE AGAIN BECOME DIFFICULT
ACROSS THIS REGION. WINDS WILL LIKELY BE A BIT GUSTY SO AREAS OF
BLOWING SNOW WILL OCCUR.
BY LATE AFTERNOON THE SNOW WILL DEVELOP FARTHER SOUTH DOWN THE I-25
CORRIDOR AND EASTERN MTN REGION. OTHERWISE...THE REST OF THE PLAINS
WILL LIKELY REMAIN DRY.
TONIGHT...
MAIN CONCERN DURING THIS PERIOD IS THE SPANISH PEAKS/RATON MESA/WET
MTNS REGION AS ALL GUIDANCE IS SHOWING PRETTY HEALTHY QPF BULLSEYES
OVER THIS REGION. FOR NOW I HAVE ISSUED A WINTER WEATHER ADVISORY
FOR THIS REGION WITH THE AREA LIKELY RECEIVING 3-6 INCHES OF SNOW AT
THE LOWER ELEVATIONS OF LAS ANIMAS AND HUERFANO COUNTIES WHILE HIGHER
ELEVATIONS WILL LIKELY RECEIVE 4 TO 10 INCHES OF SNOW. IT IS
POSSIBLE THAT THESE VALUES MAY BE ON THE LOW SIDE...ESPECIALLY IF
GUIDANCE DOES VERIFY. WILL ALLOW LATER SHIFT TO REANALYZE AND
UPGRADE TO WARNING STATUS IF LATER SIMULATIONS SHOW LARGE QPF VALUES
OVER AFOREMENTIONED REGION.
FOR THE REST OF THE PLAINS...EL PASO COUNTY SHOULD GENERALLY RECEIVE
ABOUT 2-4" OF SNOW WITH THIS EVENT WITH 2-6 IN TELLER COUNTY AND
PIKES PEAK. PUEBLO/FREMONT COUNTIES WILL LIKELY RECEIVE ANYWHERE
FROM BETWEEN 2 AND 5 INCHES. OVER THE FAR EAST PLAINS...1 TO 2
INCHES WILL BE POSSIBLE.
THE MOUNTAINS WILL CONTINUE TO SEE SNOW...HOWEVER THE SNOW WILL END
FROM S TO N ACROSS THE C MTNS LATER TONIGHT. OVERALL ANOTHER 6 TO
12 INCHES OF SNOW IS LIKELY OVER THE CONTDVD REGION
TEMPS TONIGHT WILL BE COLD ONCE AGAIN ACROSS THE ENTIRE REGION.
SINGLE DIGITS WILL OCCUR ACROSS NEARLY ALL OF THE REGION EXCEPT
TEENS MAINLY IN THE SAN LUIS VALLEY. /HODANISH
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 412 AM MST SAT NOV 15 2014
...COLD SUNDAY THEN GRADUAL WARMING...
SNOW WILL LINGER ALONG THE SOUTHERN BORDER AREAS EARLY
SUNDAY...BUT SHOULD MOSTLY END BY NOON AS PROGRESSIVE
SHORTWAVE MOVES ON THROUGH. NEW SHOT OF ARCTIC AIR WILL
BRING ONE MORE REALLY COLD DAY SUNDAY BUT THEN THINGS WILL
START TO WARM UP AND DRY OUT FOR MOST OF THE UPCOMING WEEK.
THE WARM UP MAY START A LITTLE SLOW ON MONDAY AS SNOW COVER AND
LIGHT PRESSURE GRADIENTS WILL TEND TO KEEP SURFACE INVERSIONS IN
PLACE THROUGH THE DAY. BY TUESDAY...IT LOOKS LIKE WE SHOULD SEE A
LITTLE BETTER MIXING AS DOWNSLOPE PRESSURE GRADIENTS DEVELOP. THIS
SHOULD HELP BRING CHINOOK BREEZES OFF THE MOUNTAINS TO START
WARMING THE AIR.
COULD BE A LITTLE SET BACK WEDNESDAY AS THE MODELS ARE SHOWING A
WEAK SURFACE HIGH DROPPING THROUGH THE PLAINS THIS DAY. THIS COULD
REESTABLISH INVERSIONS IF THERE IS ENOUGH COOLING WITH THE HIGH
AND IF THERE IS ANY SNOW COVER REMAINING.
THURSDAY AND ESPECIALLY FRIDAY...IT LOOKS LIKE SOME WEAK ENERGY
FROM THE PACIFIC WILL START MOVING BACK INTO THE REGION. THIS
ENERGY COULD SPREAD SOME SNOW SHOWERS INTO THE CONTINENTAL DIVIDE
THURSDAY...AND EAST TO THE REST OF THE MOUNTAINS AND PIKES PEAK
REGION ON FRIDAY. THE APPROACHING ENERGY DOESN`T LOOK STRONG AT
THIS POINT SO FORECAST CONFIDENCE IS LOW AT THIS TIME. TEMPERATURES
WILL LIKELY REMAIN MILD THURSDAY...BUT THEN START TO COOL ON
FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 412 AM MST SAT NOV 15 2014
KCOS...ARCTIC FRONT WILL CROSS KCOS AOA NOONTIME...18-19Z. WINDS
WILL SHIFT TO NORTH THAN NORTH-NORTHEAST AND BECOME GUSTY. COULD SEE
SOME SNOW SHOWERS BY MID AFTERNOON BUT EXPECT BRUNT OF IT WILL OCCUR
MORE TOWARDS SUNSET. LIFR CONDITIONS WILL BE POSSIBLE/LIKELY BETWEEN
00Z-09Z AS STEADY SNOW IS EXPECTED.
KPUB...ARCTIC FRONT WILL CROSS KPUB AOA 19-20Z WITH WINDS QUICKLY
SHIFTING TO THE NORTHEAST AND THEN EAST. PRECIP WILL LIKELY DEVELOP
AFTER SUNSET AND THERE IS A HIGH PROBABILITY THAT IT WILL SNOW...AND
IT IS EXPECTED TO ACCUMULATE TO 2-4 INCHES. LIFR CONDITIONS LIKELY
ONCE SNOW STARTS. IT WILL LAST THROUGH THE NIGHT ENDING AROUND
SUNRISE.
KALS...LOW CIGS THIS MORNING SHOULD BREAK UP ABOUT 1-2HRS AFTER
SUNRISE AS WEST WINDS INCREASE. VFR EXPECTED THROUGH THE REST OF THE
DAY WITH PRECIP DEVELOPING AFTER MIDNIGHT. SNOW WILL LIKELY
ACCUMULATE AT KALS WITH 1-2" ANTICIPATED. CIGS LIKELY WILL GO LIFR
AFTER MIDNIGHT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 9 AM MST
SUNDAY FOR COZ072>075-079-080-087-088.
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066-
068.
WINTER WEATHER ADVISORY UNTIL 5 AM MST EARLY THIS MORNING FOR
COZ073-075.
&&
$$
SHORT TERM...HODANISH
LONG TERM...LW
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1042 PM MST FRI NOV 14 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 232 PM MST FRI NOV 14 2014
...ACTIVE WEATHER CONTINUES...
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS INDICATING
MODERATE TO STRONG WESTERLY FLOW ALOFT ACROSS THE REGION WITH
ANOTHER EMBEBBED SHORT WAVE TRANSLATING ACROSS THE GREAT BASIN AND
INTO WESTERN COLORADO. REGIONAL SATELLITE AND RADAR DATA INDICATING
A GOOD SLUG OF MOISTURE MOVING INTO WESTERN COLORADO ALONG WITH A
FEW LIGHTNING STRIKES ACROSS SOUTHEASTERN UTAH AT THIS TIME.
TEMPERATURES AS OF 2 PM INDICATING SHALLOW COLD AIRMASS PERSISTING
ACROSS SOUTHERN EL PASO COUNTY AND THE LOWER ARKANSAS RIVER VALLEY
FROM CANON CITY TO LAMER...WITH TEMPS IN THE 20S TO LOWER 30S AT
THIS TIME. ELSEWHERE ACROSS THE AREA...TEMPS HAVE WARMED INTO THE
40S TO LOWER 50S WITH MAINLY 20S AND 30S ACROSS THE CONTDVD.
TONIGHT...MODELS CONTINUE TO BRING WAVE ACROSS THE AREA WITH
MODERATE TO HEAVY SNOWFALL EXPECTED ACROSS THE CENTRAL AND SOUTHWEST
MTS AND ACROSS THE HIGHER ELEVATIONS OF THE SANGRE DE CRISTO MTS
THROUGH EARLY SATURDAY MORNING. CURRENT WINTER WEATHER HIGHLIGHTS
LOOK ON TRACK WITH 4 TO 8 INCHES POSSIBLE OVERNIGHT. MODELS...TO A
VARYING DEGREE...CONTINUE TO INDICATE A BAND OF PRECIPITATION...
MOVING INTO THE LA GARITA MTS AT THIS TIME...CONTINUING TO SPREAD
EAST ACROSS THE NORTHERN SAN LUIS VALLEY AND ACROSS THE LOWER
ARKANSAS RIVER THROUGH THE LATE EVENING AND OVERNIGHT HOURS. WHILE
THE 18Z NAM LOOKS HEAVY HANDED IN QPF...RAP AND HRRR HAVE A
SIMILAR SET UP AND HAVE INCREASED POPS ACROSS THIS AREA TO MATCH
KEEPING ACCUMULATIONS OF AN INCH OR LESS AT THIS TIME.
HOWEVER...WILL NEED TO CONTINUE TO MONITOR THE DEVELOPMENT OF THIS
BAND AS THE 18Z NAM IS GIVING UP TO 3 INCHES ACROSS THE LOWER ARK
VALLEY TONIGHT. WITH EXPECTED CLOUD COVER...EXPECTING LOWS TO BE
MAINLY IN THE 20S ACROSS THE AREA.
TOMORROW...MODELS CONTINUE TO DIFFER ON TIMING OF THE NEXT SLUG OF
ARCTIC AIR TO INVADE EASTERN COLORADO...ESPECIALLY ITS ASSOCIATED
PRECIPITATION FIELD. NAM AND EC CONTINUE TO BE SLOWER WITH THE
UPPER TROUGH MOVING ACROSS THE ROCKIES WITH THE GFS REMAINING
FASTER. AT ANY RATE...HAVE PLAYED THE TIMING OF THE ARCTIC FRONT
ACROSS THE PALMER DVD AROUND 18Z...THOUGH HAVE DELAYED ONSET OF
PRECIPITATION INTO THE LATE AFTERNOON. GUSTY NORTH TO NORTHEAST
WINDS OF 20 TO 30 MPH TO ANNOUNCE THE ARRIVAL OF THE FRONT...WHICH
MAY BE ENOUGH TO BRIEFLY MIX OUT THE SHALLOW COLD AIRMASS IN PLACE
ACROSS THE LOWER ARK VALLEY...BEFORE TEMPS COOL AGAIN BEHIND THE
FRONT. NEEDLESS TO SAY...FORECASTING HIGH TEMPERATURES TOMORROW
WILL AGAIN BE A CHALLENGE.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 232 PM MST FRI NOV 14 2014
...SNOW CONTINUES SATURDAY NIGHT THROUGH SUNDAY...
UPPER TROF WILL DROP IN FROM THE NORTHWEST SATURDAY NIGHT BRINGING
A HEALTHY BOUT OF UPPER FORCING ACROSS THE AREA IS IT DROPS TO THE
SOUTHEAST. THERE ARE STILL SOME TIMING DIFFERENCES IN THE MODELS
WITH THE ONSET OF THE PRECIPITATION...ESPECIALLY FOR THE SOUTHEAST
MTS/PLAINS. GFS IS A TOUCH FASTER WITH THE SOUTHWARD PROGRESSION
OF THE UPPER TROF...WHICH MAY BE THE REASON IT IS TRENDING FASTER
WITH THE ONSET OF PRECIPITATION VS THE SLOWER NAM12 AND ECMWF.
FRONT WILL HAVE ALREADY BLASTED THROUGH SOUTHEAST CO BY 00Z
SUN...AND GIVEN ITS ARCTIC ORIGIN...THIS TIMING LOOKS REASONABLE.
HOWEVER...WITH THE UPPER FORCING IS STILL WELL OFF TO THE NORTH
DURING THIS TIME PERIOD...AND A SLOWER TIMING TO THE ONSET OF
PRECIPITATION...ESP FOR THE SE PLAINS...SEEMS MORE REASONABLE.
NORTHEAST UPSLOPE BEHIND THE FRONT IS RATHER SHALLOW (BELOW H7) BUT
AS UPPER TROF DROPS IN FROM THE NORTHWEST...THERE WILL BE A PERIOD
OF UPGLIDE OVER THE COLD DOME DURING THE EVENING AND OVERNIGHT
HOURS. THE GFS SHOWS SOME PRETTY GOOD DIV-Q...THE CORE OF WHICH
PASSES ACROSS UT/THE 4 CORNERS REGION/SRN CO/AND NORTHERN NM. SO
ALTHOUGH UPSLOPE IS SHALLOW FOR THE SOUTHEAST MTS...AND NOT THE
BEST FOR THE SOUTHWEST MOUNTAINS WITH FLOW ALOFT MORE WESTERLY
(INSTEAD OF THE MORE FAVORABLE SOUTHWEST DIRECTION)...HAVE SEEN
THESE DYNAMIC SYSTEMS PRODUCE WIDESPREAD MODERATE TO HEAVY
SNOWFALL AMOUNTS. WITH TIMING OF THE FORCING EXITING SOUTHERN CO
AROUND OR SHORTLY AFTER 12Z SUN...PLAN TO KEEP THE HEADLINE TIMING
FOR THE CONTINENTAL DIVIDE AS IS FOR NOW. HOWEVER...IF MOISTURE
DIMINISHES RAPIDLY ENOUGH BEHIND THE TROF...ITS POSSIBLE THAT THE
SNOW MAY DECREASE A BIT SOONER FARTHER NORTH ACROSS THE SAWATCH
AND MOSQUITO RANGES. GIVEN THE INCONSISTENCIES BETWEEN
MODELS...WILL LET LATER SHIFTS REFINE THE TIMING AS NEED BE.
ADDITIONAL SNOWFALL AMOUNTS IN THE 4 TO 8 INCH RANGE LOOKS
REASONABLE ALONG THE CONTINENTAL DIVIDE SAT NIGHT GIVEN THE
PROBABILITY FOR 20+/1 LIQUID/SNOW RATIOS. STILL SOME UNCERTAINTY
FOR SNOWFALL AMOUNTS ACROSS THE SOUTHEAST MOUNTAINS...AS THE GFS
IS HEAVIER WITH QPF ACROSS THE PIKES PEAK REGION VS THE DRIER
NAM12. HUNCH IS THAT SOUTHEAST MOUNTAINS AND PORTIONS OF THE I-25
CORRIDOR MAY NEED AN ADVISORY SAT NIGHT...WITH THE WETS AND
SANGRES LIKELY TO SEE SOMEWHERE IN THE 3-8 INCH RANGE. TELLER AND
EL PASO COUNTIES STILL VERY MUCH IN THE AIR WITH NAM SUGGESTING
ONLY AN INCH OR TWO SAT NIGHT...WHILE GFS HAS 2 TO NEARLY 4
INCHES. GIVEN THE TRACK OF THE STRONGER FORCING ALOFT...IT DOES
MAKE SENSE THAT THE LIGHTER NAM12 AMOUNTS COULD BE MORE
REASONABLE. SUSPECT THAT SOME BANDING OF SNOW ALONG/SOUTH OF THE
ARKANSAS RIVER WILL EXTEND EASTWARD ACROSS THE SOUTHEAST
PLAINS...BUT SNOWFALL AMOUNTS AT THIS TIME APPEAR TO STAY BELOW
ADVISORY LEVELS...PERHAPS 1-3" RANGE. AGAIN GIVEN THE COLD AIRMASS
WITH THIS EVENT...IT SHOULD BE ANOTHER DRY FLUFFY SNOW EVENT. THE
DIFFERENCE THIS TIME WILL BE THAT THE ROAD SURFACES WILL START OUT
COLDER GIVEN OUR PREVIOUS COLD OUTBREAK. THIS COULD LIMIT THE
ICING FACTOR SOME DEPENDING ON ASPHALT TEMPERATURES SATURDAY
AFTERNOON.
SNOW WILL END FROM NORTH TO SOUTH DURING THE MORNING ON
SUNDAY...AND SNOW COVER WILL LIKELY KEEP TEMPERATURES FROM WARMING
MUCH. HAVE DROPPED HIGHS A FEW DEGREES FROM THE CONSENSUS
GRIDS...WHICH PUTS THEM CLOSER TO THE COLDER SIDE OF GUIDANCE
VALUES.
FORECAST DRIES OUT FOR THE REMAINDER OF THE EXTENDED. ANOTHER
SURFACE HIGH DESCENDS THROUGH THE PLAINS WITH SOME UNCERTAINTIES
AS TO HOW FAR WEST THE CORE OF COLD AIR ASSOCIATED WITH IT WILL
GET. NAM12 AND EC ARE SEVERAL DEGREES COOLER WITH H7 TEMPS ACROSS
THE PLAINS VS THE WARMER GFS MONDAY AFTERNOON...WHICH PUTS HIGH
TEMPERATURES IN QUESTION ACROSS THE PLAINS. CURRENT GRIDS ARE
CARRYING MID 20S TO AROUND 30...BUT THESE MAY NEED TO BE COOLED
OFF EVEN FURTHER DEPENDING ON HOW THIS EVOLVES.
NORTHERLY FLOW ALOFT GRADUALLY SHIFTS TO A MORE WESTERLY DIRECTION WHICH
SHOULD BRING SOME MODERATING TEMPERATURES THROUGH MID TO LATE
WEEK. ANOTHER PACIFIC SYSTEM MAY CUT THROUGH THE WESTERN U.S.
UPPER RIDGE TOWARDS FRIDAY. FORECAST WILL CARRY GENERALLY DRY
CONDITIONS UNTIL FRIDAY WITH TEMPERATURES WARMING BUT STILL
REMAINING BELOW NORMAL. -KT
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1042 PM MST FRI NOV 14 2014
PRIMARILY VFR CONDITIONS ARE ANTICIPATED AT THE KALS...KCOS AND
KPUB TAF SITES INTO SATURDAY AFTERNOON(OUTSIDE OF KALS...WHERE
SOME LOW CLOUDS WILL BE POSSIBLE AT TIMES TONIGHT). METEOROLOGICAL
CONDITIONS ARE THEN EXPECTED TO DETERIORATE FROM LATE SATURDAY
AFTERNOON INTO SATURDAY NIGHT...ESPECIALLY OVER THE KCOS AND KPUB
TAF SITES AS MOIST NORTH TO NORTHEASTERLY SURFACE FLOW DEVELOPS IN
THE WAKE OF A MODIFIED ARCTIC FRONT PROJECTED TO PUSH ACROSS THE
SOUTHEASTERN COLORADO PLAINS DURING SATURDAY AFTERNOON.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066-
068.
WINTER WEATHER ADVISORY UNTIL 5 AM MST SATURDAY FOR COZ073-075.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1037 PM EST SUN NOV 16 2014
.SYNOPSIS...
RAIN CHANCES WILL INCREASE OVERNIGHT INTO MONDAY AS A COLD FRONT
APPROACHES...WITH ISOLATED THUNDERSTORMS POSSIBLE MAINLY IN THE
AFTERNOON. THE FRONT WILL PUSH OFFSHORE MONDAY EVENING WITH MUCH
COLDER AIR ON TAP FOR THE REGION TUESDAY THROUGH THE END OF THE
WEEK.
&&
.NEAR TERM /UNTIL 7 AM MONDAY MORNING/...
SHOWERS CONTINUE MOVING INTO EASTERN GA AND THE UPSTATE WITH THE
COLD FRONT CURRENTLY STRETCHED FROM CENTRAL TN THROUGH
SOUTHEASTERN LA. EXPECT THE SHOWERS TO CONTINUE MOVING EASTWARD
AND INTO THE WESTERN MIDLANDS SHORTLY AFTER MIDNIGHT AND SPREAD
INTO THE EASTERN MIDLANDS BY DAYBREAK. WITH INCREASING MOISTURE
FOG WILL ALSO BE A CONCERN...ESPECIALLY IN THE EASTERN MIDLANDS
AND SOUTHERN CSRA. HAVE INCLUDED FOG IN THE FORECAST FOR MOST OF
THE FORECAST AREA WITH FOG MOVING INTO THE EASTERN MIDLANDS AROUND
MIDNIGHT AND SPREADING INTO THE WESTERN MIDLANDS DURING THE EARLY
MORNING HOURS. DENSE FOG WILL BE POSSIBLE DURING THE EARLY MORNING
HOURS...HOWEVER CONFIDENCE IS CURRENTLY NOT HIGH ENOUGH TO INCLUDE
MENTION OF DENSE FOG. TEMPERATURES HAVE REMAINED STEADY OVER THE
PAST COUPLE OF HOURS AND WITH INCREASING CLOUDS OVERNIGHT WILL SEE
TEMPERATURES BEGIN TO RISE BEFORE DAYBREAK. OVERNIGHT LOWS WILL BE
IN THE MIDDLE 40S TO AROUND 50.
&&
.SHORT TERM /7 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
BROAD AND DEEP UPPER LEVEL LOW CENTERED OVER THE GREAT LAKES EARLY
IN THE PERIOD WILL SHIFT TO THE EAST. THIS WILL DRIVE A STRONG
COLD FRONT THROUGH THE REGION MONDAY AFTERNOON. MODELS APPEAR A
LITTLE FASTER MOVING FRONT CLEARING THE MIDLANDS BEFORE 00Z TUESDAY.
DEEP AND STRONG SOUTH- SOUTHWEST FLOW AHEAD OF THE FRONT WILL
TRANSPORT MOISTURE INTO THE AREA FROM THE GULF OF
MEXICO...PRECIPITABLE WATER INCREASE TO AROUND 1.6 INCHES...WELL
ABOVE NORMAL FOR THIS TIME OF YEAR. DEWPOINTS POSSIBLY INTO THE
60S. 850MB JET 50 TO 60 KTS THROUGH EARLY AFTERNOON AND DEEP LAYER
SHEAR STRONG. MODELS MORE UNSTABLE AHEAD OF THE FRONT THAN
PREVIOUS RUNS WITH SURFACE BASED LI TO -2 IN THE CENTRAL AND EAST.
CAPE APPEARS LOW...AROUND 500 J/KG. SO HSLC SITUATION...AND
MARGINAL SEVERE THREAT WITH DAMAGING WINDS. THUNDERSTORMS FORECAST
THREAT MAINLY EAST...ESPECIALLY PEE DEE. LOW LEVEL COOL STABLE AIR
LIKELY TO SCOURER OUT DURING THE MORNING DUE TO STRONG SOUTH LOW
LEVEL FLOW DEVELOPING AHEAD OF THE FRONT/STRONG WARM
ADVECTION/ISENTROPIC LIFT SO PREFER WARMER GUIDANCE FOR MAXIMUM
TEMPERATURES. MID 60S TO THE LOWER TO MID 70S EAST. LOW LEVEL
CONVERGENCE STRONG...GUIDANCE POPS GENERALLY CATEGORICAL IN THE
THROUGH EARLY AFTERNOON.
MODELS FASTER MOVING FRONT THROUGH THE AREA...POPS DECREASING FAST
AS STRONG COLD ADVECTION DEVELOPS. CUT POPS BACK FROM PREVIOUS
FORECAST BY 00Z TUESDAY. CLEARING OVERNIGHT WITH TEMPERATURES
FALLING INTO THE UPPER 20S TO MID 30S. WINDS LIKELY TO STAY UP
OVERNIGHT BUT WITH STRONG COLD ADVECTION...COOLER GUIDANCE MAY BE
ON TRACK.
THE MAIN COLD FRONT AND ASSOCIATED RAINFALL WILL PUSH THROUGH THE
CWA THROUGH THE DAY MONDAY. COULD SEE GOOD WARM ADVECTION PATTERN
AHEAD OF THE FRONT...WHICH WOULD ALLOW TEMPERATURES TO RISE INTO
THE 60S...TO POSSIBLY LOWER 70S IN AREAS. THIS WILL ALSO HELP
TRANSPORT MOISTURE FROM THE NORTHWARD AHEAD OF THE FRONT...AND
EXPECT MOST AREAS WILL SEE SOME AMOUNT OF RAINFALL THROUGH THE
DAY...SO CATEGORICAL POPS WOULD APPEAR TO BE IN ORDER. WEAK
INSTABILITY WILL BE ENCOUNTERED AHEAD OF THE FRONT...SO SOME
THUNDER MAY BE POSSIBLE THROUGH THE DAY MONDAY. THERE WILL ALSO BE
SOME POTENTIAL FOR GUSTY WINDS MONDAY AFTERNOON AND EVENING AHEAD
OF THE FRONT. STRONG LOW TO MID LEVEL JET 20 TO 30 KTS. WIND MAY
MIX DOWN AS FRONT MOVES THROUGH THE AREA.
THE MAIN FRONT WILL BE PUSHING EAST OF THE CWA BY MONDAY
EVENING...AND ALL AREAS SHOULD BE DRY BY MIDNIGHT MONDAY NIGHT.
EXPECTING A RAPID DECREASE IN POPS...DEWPOINTS...AND TEMPERATURES
AFTER MIDNIGHT. MOSTLY SUNNY TUESDAY AND UNSEASONABLE COOL WITH
TEMPERATURES IN THE 40S WITH FULL SUN AND BREEZY AT TIMES ALTHOUGH
SURFACE PRESSURE GRADIENT WILL BE RELAXING IN THE AFTERNOON AS
RIDGE BUILDS EAST FROM THE LOWER MISSISSIPPI VALLEY.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
COLD ARCTIC AIR MASS WILL BE BUILDING INTO THE AREA THROUGH THE
EARLY PART OF THE LONGER TERM PERIOD. A VERY UNSEASONABLY COLD
NIGHT EXPECT TUESDAY NIGHT WITH STRONG RADIATIONAL COOLING
CONDITIONS EXPECTED. CONFIDENCE HIGH FOR RECORD LOW TEMPERATURES
WEDNESDAY MORNING. CONTINUED TO FORECAST MINIMUM TEMPERATURES ON
THE LOW SIDE OF THE GUIDANCE GIVEN THE DRY AIR MASS AND STRONG
RADIATIONAL COOLING CONDITIONS IN THE RIDGE AXIS. WEAKER COLD
FRONT FRIDAY MAY RESULT IN A FEW SHOWERS...MODIFIED CANADIAN AIR
MASS OVER THE WEEKEND...TEMPERATURES EXPECTED TO BE A LITTLE
WARMER THAN MID WEEK.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
HIGH CONFIDENCE IFR/LIFR CONDITIONS OVERNIGHT THROUGH MID-MORNING
MONDAY.
WEDGE PATTERN HOLDING MVFR CIGS ACROSS THE TAF SITES THIS EVENING
WILL WEAKEN AS A WARM FRONT LIFTS NORTH OVERNIGHT. CIG/VSBY WILL
DETERIORATE TO IFR/LIFR 04Z-06Z. CONFIDENCE IS HIGH NOW THAT HIGH
RESOLUTION HRRR MODEL AND RAPID REFRESH ENSEMBLE SYSTEM INDICATING
LIFR DURING THE EARLY MORNING HOURS.
LIGHT NORTHEAST WINDS WILL VEER TO THE SOUTHEAST OVERNIGHT THEN
BECOME SOUTHERLY BY 12Z. HAVE INCLUDED LLWS OVERNIGHT INTO
MID-MORNING MONDAY GIVEN 40 TO 50 KNOT WINDS BELOW 2000 FEET.
IFR/LIFR CONDITIONS SHOULD LINGER THROUGH MID MORNING. SOUTHERLY
WINDS WILL INCREASE AHEAD OF AN APPROACHING COLD FRONT AS A LOW
LEVEL JET CROSSES THE REGION...ALLOWING CIGS TO LIFT TO MVFR. BEST
CHANCE FOR CONVECTION WILL BE 17Z-22Z AS THE COLD FRONT CROSSES THE
TAF SITES. ISOLATED STRONG TO SEVERE STORMS POSSIBLE. BY THE END OF
THE TAF PERIOD NORTHWEST WINDS 10 TO 15 KNOTS WITH GUSTS 20 TO 25
KNOTS...AND DOWNSLOPE FLOW WILL BEGIN CLEARING SKIES.
EXTENDED AVIATION OUTLOOK...NO RESTRICTIONS TO AVIATION EXPECTED
MONDAY NIGHT THROUGH FRIDAY.
&&
.CLIMATE...
RECORD LOW TEMPERATURES FORECAST WEDNESDAY MORNING 11/19...
CURRENT RECORDS...
COLUMBIA...22 DEGREES SET IN 2008,1891.
AUGUSTA....22 DEGREES SET IN 2008.
CURRENT FORECAST...
COLUMBIA...19
AUGUSTA....18
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...FLASH FLOOD WATCH THROUGH MONDAY EVENING FOR SCZ030.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1208 PM CST SAT NOV 15 2014
.UPDATE...
ISSUED AT 1207 PM CST SAT NOV 15 2014
SNOW CONTINUES TO EXPAND ACROSS CENTRAL IOWA. THE EARLY MORNING
ACTIVITY BROUGHT AROUND 3 INCHES OVER THE FAR NORTHWEST. THE
HEAVIES SNOWFALL RATES WILL SHIFT INTO CENTRAL IOWA THIS AFTERNOON
NEAR THE STRONGEST MID LEVEL FRONTOGENESIS. GRADUALLY COOLING
PROFILES WILL LEAD TO A DEEP DENDRITIC LAYER FROM NEAR 900 MB TO
500 MB. THESE TYPE EVENTS TEND TO BE EFFICIENT SNOW DEPTH PRODUCING
EVENTS WITH A PROLONGED PERIOD OF DENDRITES LEADING TO HIGH SNOW
RATIOS NEAR 20 TO 1. SNOW INTENSITIES WILL DIMINISH FOR A PERIOD
LATE AFTERNOON INTO THE EARLY EVENING. A VIGOROUS UPPER LEVEL
SHORT WAVE OVER WYOMING WITH KINEMATIC FORCING MOVING AHEAD
THROUGH CENTRAL SOUTH DAKOTA AND NORTHWEST NEBRASKA. THIS ENERGY
WILL ARRIVE THIS EVENING AND BRING A RENEWED BAND OF SNOW AND
ADDITIONAL ACCUMULATIONS. A WIDESPREAD 2 TO 4 INCHES STILL IS
EXPECTED WITH A FEW LOCATIONS APPROACHING 6 INCHES OVER THE
NORTHWEST.
&&
.SHORT TERM /TODAY/...
ISSUED AT 303 AM CST SAT NOV 15 2014
NO MAJOR CHANGES WITH ONGOING FORECAST FOR THE FIRST
SIGNIFICANT SNOWFALL OF THE SEASON AS MODELS REMAIN IN GOOD
AGREEMENT WITH EXPECTED SNOW TODAY. USED A BLEND OF THE
HRRR/HOPWRF FOR TIMING OF PRECIP AND NAM/ECMWF TEMPS.
BROAD ISENTROPIC LIFT AND DECENT MOISTURE TRANSPORT DEVELOP OVER
WESTERN TO NORTHWEST IOWA THIS MORNING AND QUICKLY BLOSSOMS ACROSS
THE REMAINDER OF THE STATE THIS AFTERNOON. ONE MINOR CHANGE WAS
START THE SNOW A LITTLE SOONER THIS MORNING OVER THE WEST TO
NORTHWEST AS SNOW ALREADY DEVELOPING ALOFT AND SNOW SHOULD START
REACHING THE SURFACE BETWEEN 12-14Z THIS MORNING. THE 15.03Z
HOPWRF AND 15.05Z HRRR HAVE SNOW MOVING INTO THE WESTERN EDGES OF
THE FORECAST AREA BETWEEN 13-15Z. THE FORECAST SOUNDINGS ACROSS
NORTHERN IOWA BECOME COMPLETELY SATURATED BY 17-18Z TODAY AND THE
STRONGER OMEGA IS JUST AT THE TOP EDGE OF THE DENDRITIC LAYER BUT
ENOUGH OVERLAP TO SEE SOME DECENT FLAKES...AND THUS SLIGHTLY
HIGHER SNOW ACCUMULATION THIS AFTERNOON OVER NORTHERN IOWA. RAP IS
A BIT LESS WITH THE FORCING THAN THE NAM/GFS AND HAS SLIGHTLY
LOWER SNOW AMOUNTS GOING...BUT STILL DEPICTS ENOUGH SNOW TO
WARRANT ADVISORY. FURTHER SOUTH...SOUNDINGS NOT TOO DISSIMILAR
THAN NORTHERN IOWA...WITH THE MAIN DIFFERENCE BEING JUST SLIGHTLY
LESSER FORCING WITHIN THE DENDRITIC LAYER. THIS RESULTING IN LESS
SNOW AMOUNTS OVER THE SOUTHERN TWO-THIRDS OF THE FORECAST AREA.
LEANED TOWARD A BLEND OF THE WARMER NAM/ECMWF FOR TEMPERATURES
TODAY. THIS RESULTED IN SNOW RATIOS AROUND 17:1 TO 18:1 OVER
NORTHERN IOWA AND 15:1 TO 16:1 ACROSS THE SOUTH...BASED ON 925M
TO 700MB THICKNESS. HAVE 100 POPS GOING MUCH OF THE AFTERNOON WITH
HIGH CONFIDENCE ALL OF CENTRAL IOWA WILL BE SNOWING BY OR SHORTLY
PAST 18Z. VERY LITTLE WIND TODAY BUT WITH THE FLUFFY SNOW TYPE
EXPECTED AND AT TIMES FALLING MODERATELY...THIS SHOULD BE ENOUGH
TO CAUSE SOME VISIBILITY RESTRICTION WITH A 6-9 KNOT WIND.
.LONG TERM /TONIGHT THROUGH FRIDAY/...
ISSUED AT 303 AM CST SAT NOV 15 2014
ACTIVE WEATHER WILL CONTINUE THROUGH THE WEEKEND AND EARLY NEXT
WEEK FOLLOWING TONIGHTS SYSTEM...ANOTHER INTENSE UPPER LEVEL LOW
WILL DROP SOUTH INTO THE NORTHERN GREAT LAKES SUNDAY NIGHT AND
MONDAY MORNING. TONIGHT...SYSTEM EXITING THE AREA TO THE EAST
DURING THE EVENING HOURS. BEST FORCING ALONG H500 AND SFC TROUGH
NEAR 00Z FOCUSING ON H700 BOUNDARY ACROSS NORTHERN IOWA. THROUGH
06Z THIS H700 BOUNDARY PUSHES EAST WITH TROUGH RESULTING IN
LESSENING FORCING WEST OF I35 DURING THE LATE EVENING. BY 12Z BEST
FORCING EAST OF THE AREA WITH SOME RESIDUAL LIGHT SNOW/FLURRIES
OVER THE NORTHEAST ENDING QUICKLY WITH CLOUDS DEPARTING IN THE
MORNING SUNDAY. SNOW RATIOS OF 18 TO 20:1 AND EXPECTED QPF AMOUNT
YIELD SNOWFALL AMOUNTS OF UP TO ANOTHER 1.5 INCHES TONIGHT DURING
THE EVENING AND OVERNIGHT HOURS. FORTUNATELY THE WINDS WILL BE
LIGHT DURING THE EVENT...SO BLOWING SNOW WILL NOT BE AN ISSUE
TONIGHT. WITH CLEARING BY MORNING...LOWS WILL QUICKLY FALL
NORTHWEST AND WEST INTO THE SINGLE DIGITS WITH TEENS I35 EAST.
SUNDAY WILL INITIALLY SEE SOME SUNSHINE BETWEEN WAVES BUT CLOUDS
WILL INCREASE WEST DURING THE AFTERNOON. WITH H850 TEMPS IN THE
-10C TO -12C RANGE AND WESTERLY WINDS...TEMPERATURES WILL BE
TOLERABLE IN THE MID 20S OVER MOST OF THE AREA. AN APPROACHING
COLD FRONT WILL SPREAD CLOUDS ACROSS THE REGION THROUGH EARLY
EVENING. THE SECOND STRONG H500 LOW WILL FORCE A BULGE OF COLD AIR
QUICKLY SOUTHEAST INTO WESTERN IOWA SUNDAY EVENING WITH RATHER
STRONG COLD AIR ADVECTION AND INCREASING WINDS ALOFT. BY 12Z H850
TEMPS WILL HAVE FALLEN ANOTHER 8 TO 10C WITH READINGS FROM -16C TO
-20C. THROUGH THE DAY MONDAY CLOUD COVER WILL OVERTAKE THE AREA
WITH H850 TEMPS SETTLING TOWARD -18C TO -20C REGION WIDE. MODELS
HAVE BEEN CONSISTENT WITH STEEPENING LAPSE RATES NEAR 15Z AND
STRONG MIXING THROUGH THE DAY...POTENTIAL FOR SNOW SHOWERS ACROSS
THE NORTHEAST WITH FLURRIES CENTRAL AND SOUTH. ALL IN ALL...MONDAY
IS LOOKING RATHER UNPLEASANT. POTENTIAL FOR 15 TO 25 MPH WINDS
WITH GUSTS TO NEAR 35 MPH AT TIMES. THIS WILL CAUSE PATCHY TO
AREAS BLOWING SNOW OVER MUCH OF THE NORTHEAST HALF OF THE AREA
WITH REDUCTIONS TO VISIBILITY. HEADLINES MAY BE NEEDED AGAIN ON
MONDAY FOR THE COMBINATION OF WIND...BLOWING SNOW...AND COLD. HAVE
EXPANDED THE POTENTIAL FOR LIGHT PRECIP AND BLOWING SNOW MONDAY
ACROSS THE AREA. HIGHS WILL RECOVER LITTLE FROM FRIGID MORNING
LOWS IN THE SINGLE DIGITS TO LOWER TEENS. BY AFTERNOON HIGHS NORTH
WILL REACH THE LOWER TEENS TO THE LOWER 20S IN THE SOUTHEAST. TO
TOP OFF THE WONDERFUL DAY...MINIMUM RECORD HIGHS LOOK LIKELY TO BE
SET AT MANY LOCATIONS...ONE WHICH HAS NOT BEEN SEEN SINCE THE
1890S AND MANY SINCE THE 1950S. IN FACT...OUR HIGHS MONDAY WOULD
STILL BE ABOUT 10 TO 15 DEGREES BELOW OUR COLDEST AVERAGE HIGHS
FOR THE NORMALLY COLDEST WINTER DAY OF THE YEAR...OR ABOUT 30
DEGREES BELOW OUR NORMAL FOR 11/17. WE HAVENT HAD HIGHS THIS COLD
SINCE EARLY MARCH OF 2014. TUESDAY WILL BEGIN QUITE COLD WITH A
RIDGE JUST EDGING INTO THE AREA BUT WARM BY AFTERNOON. QUICKLY
ANOTHER CLIPPER OVER THE NORTHERN PLAINS WILL MODERATE THE AIRMASS
WITH BRISK WEST WINDS DEVELOPING DURING THE DAY. TEMPS WILL RISE
INTO THE 20S. ANOTHER ARCTIC FRONT WILL DROP SOUTH INTO THE AREA
TUESDAY NIGHT BUT THE AIRMASS WILL NOT BE QUITE AS COLD AS THE
PREVIOUS. THE REMAINDER OF THE WEEK FEATURES A SERIES OF ARCTIC
SHORT WAVES ROTATING AROUND THE HUDSON BAY PARENT H500
LOW...PULLING ADDITIONAL COLD AIR TOWARD THE GREAT PLAINS. NEXT
WEEK WILL FEATURE DAYS WITH CLOUD COVER MIXED WITH SOME SUNSHINE
AND CHILLY READINGS. FORTUNATELY BY LATE IN THE EXTENDED...TOWARD
SATURDAY THE CROSS POLAR FLOW CUTS OFF...THE H500 RIDGE ACROSS THE
WEST COAST BREAKS DOWN AND MORE ZONAL FLOW RESULTS OVER THE
ROCKIES. THIS WILL CAUSE CHINOOKS COMPRESSIONAL HEATING OVER THE
PLAINS AND MODERATE HIGHS TO ABOVE FREEZING. FROM WEDNESDAY
THROUGH FRIDAY HIGHS WILL APPROACH THE 30 DEGREE MARK WITH LOWS
MODERATING INTO THE TEENS OVER THE AREA. LITTLE PRECIPITATION IS
EXPECTED FOR MUCH OF THE PERIOD NEXT WEEK.
&&
.AVIATION...15/18Z
ISSUED AT 1147 AM CST SAT NOV 15 2014
CONDITIONS WILL CONTINUE TO DETERIORATE ACROSS SITES THIS
AFTERNOON AS LOWER CIGS AND SNOW MOVE INTO THE AREA. A PERIOD OF
IMPROVED VSBYS EXPECTED BY LATE AFTERNOON THROUGH EARLY EVENING
BEFORE ANOTHER BAND OF SNOW ARRIVES. CIGS WILL RANGE FROM IFR TO
MVFR THROUGH MUCH OF THE PERIOD. SOUTHEAST WINDS WILL BECOME
WEST/NORTHWEST LATE TONIGHT.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR ADAIR-
ADAMS-APPANOOSE-AUDUBON-BLACK HAWK-BOONE-BREMER-BUTLER-CALHOUN-
CARROLL-CASS-CERRO GORDO-CLARKE-CRAWFORD-DALLAS-DAVIS-DECATUR-
EMMET-FRANKLIN-GREENE-GRUNDY-GUTHRIE-HAMILTON-HANCOCK-HARDIN-
HUMBOLDT-JASPER-KOSSUTH-LUCAS-MADISON-MAHASKA-MARION-MARSHALL-
MONROE-PALO ALTO-POCAHONTAS-POLK-POWESHIEK-RINGGOLD-SAC-STORY-
TAMA-TAYLOR-UNION-WAPELLO-WARREN-WAYNE-WEBSTER-WINNEBAGO-WORTH-
WRIGHT.
&&
$$
UPDATE...DONAVON
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...DONAVON
AREA FORECAST DISCUSSION
NWS DES MOINES IA
539 AM CST SAT NOV 15 2014
...UPDATED AVIATION DISCUSSION...
.SHORT TERM /TODAY/...
ISSUED AT 303 AM CST SAT NOV 15 2014
NO MAJOR CHANGES WITH ONGOING FORECAST FOR THE FIRST
SIGNIFICANT SNOWFALL OF THE SEASON AS MODELS REMAIN IN GOOD
AGREEMENT WITH EXPECTED SNOW TODAY. USED A BLEND OF THE
HRRR/HOPWRF FOR TIMING OF PRECIP AND NAM/ECMWF TEMPS.
BROAD ISENTROPIC LIFT AND DECENT MOISTURE TRANSPORT DEVELOP OVER
WESTERN TO NORTHWEST IOWA THIS MORNING AND QUICKLY BLOSSOMS ACROSS
THE REMAINDER OF THE STATE THIS AFTERNOON. ONE MINOR CHANGE WAS
START THE SNOW A LITTLE SOONER THIS MORNING OVER THE WEST TO
NORTHWEST AS SNOW ALREADY DEVELOPING ALOFT AND SNOW SHOULD START
REACHING THE SURFACE BETWEEN 12-14Z THIS MORNING. THE 15.03Z
HOPWRF AND 15.05Z HRRR HAVE SNOW MOVING INTO THE WESTERN EDGES OF
THE FORECAST AREA BETWEEN 13-15Z. THE FORECAST SOUNDINGS ACROSS
NORTHERN IOWA BECOME COMPLETELY SATURATED BY 17-18Z TODAY AND THE
STRONGER OMEGA IS JUST AT THE TOP EDGE OF THE DENDRITIC LAYER BUT
ENOUGH OVERLAP TO SEE SOME DECENT FLAKES...AND THUS SLIGHTLY
HIGHER SNOW ACCUMULATION THIS AFTERNOON OVER NORTHERN IOWA. RAP IS
A BIT LESS WITH THE FORCING THAN THE NAM/GFS AND HAS SLIGHTLY
LOWER SNOW AMOUNTS GOING...BUT STILL DEPICTS ENOUGH SNOW TO
WARRANT ADVISORY. FURTHER SOUTH...SOUNDINGS NOT TOO DISSIMILAR
THAN NORTHERN IOWA...WITH THE MAIN DIFFERENCE BEING JUST SLIGHTLY
LESSER FORCING WITHIN THE DENDRITIC LAYER. THIS RESULTING IN LESS
SNOW AMOUNTS OVER THE SOUTHERN TWO-THIRDS OF THE FORECAST AREA.
LEANED TOWARD A BLEND OF THE WARMER NAM/ECMWF FOR TEMPERATURES
TODAY. THIS RESULTED IN SNOW RATIOS AROUND 17:1 TO 18:1 OVER
NORTHERN IOWA AND 15:1 TO 16:1 ACROSS THE SOUTH...BASED ON 925M
TO 700MB THICKNESS. HAVE 100 POPS GOING MUCH OF THE AFTERNOON WITH
HIGH CONFIDENCE ALL OF CENTRAL IOWA WILL BE SNOWING BY OR SHORTLY
PAST 18Z. VERY LITTLE WIND TODAY BUT WITH THE FLUFFY SNOW TYPE
EXPECTED AND AT TIMES FALLING MODERATELY...THIS SHOULD BE ENOUGH
TO CAUSE SOME VISIBILITY RESTRICTION WITH A 6-9 KNOT WIND.
.LONG TERM /TONIGHT THROUGH FRIDAY/...
ISSUED AT 303 AM CST SAT NOV 15 2014
ACTIVE WEATHER WILL CONTINUE THROUGH THE WEEKEND AND EARLY NEXT
WEEK FOLLOWING TONIGHTS SYSTEM...ANOTHER INTENSE UPPER LEVEL LOW
WILL DROP SOUTH INTO THE NORTHERN GREAT LAKES SUNDAY NIGHT AND
MONDAY MORNING. TONIGHT...SYSTEM EXITING THE AREA TO THE EAST
DURING THE EVENING HOURS. BEST FORCING ALONG H500 AND SFC TROUGH
NEAR 00Z FOCUSING ON H700 BOUNDARY ACROSS NORTHERN IOWA. THROUGH
06Z THIS H700 BOUNDARY PUSHES EAST WITH TROUGH RESULTING IN
LESSENING FORCING WEST OF I35 DURING THE LATE EVENING. BY 12Z BEST
FORCING EAST OF THE AREA WITH SOME RESIDUAL LIGHT SNOW/FLURRIES
OVER THE NORTHEAST ENDING QUICKLY WITH CLOUDS DEPARTING IN THE
MORNING SUNDAY. SNOW RATIOS OF 18 TO 20:1 AND EXPECTED QPF AMOUNT
YIELD SNOWFALL AMOUNTS OF UP TO ANOTHER 1.5 INCHES TONIGHT DURING
THE EVENING AND OVERNIGHT HOURS. FORTUNATELY THE WINDS WILL BE
LIGHT DURING THE EVENT...SO BLOWING SNOW WILL NOT BE AN ISSUE
TONIGHT. WITH CLEARING BY MORNING...LOWS WILL QUICKLY FALL
NORTHWEST AND WEST INTO THE SINGLE DIGITS WITH TEENS I35 EAST.
SUNDAY WILL INITIALLY SEE SOME SUNSHINE BETWEEN WAVES BUT CLOUDS
WILL INCREASE WEST DURING THE AFTERNOON. WITH H850 TEMPS IN THE
-10C TO -12C RANGE AND WESTERLY WINDS...TEMPERATURES WILL BE
TOLERABLE IN THE MID 20S OVER MOST OF THE AREA. AN APPROACHING
COLD FRONT WILL SPREAD CLOUDS ACROSS THE REGION THROUGH EARLY
EVENING. THE SECOND STRONG H500 LOW WILL FORCE A BULGE OF COLD AIR
QUICKLY SOUTHEAST INTO WESTERN IOWA SUNDAY EVENING WITH RATHER
STRONG COLD AIR ADVECTION AND INCREASING WINDS ALOFT. BY 12Z H850
TEMPS WILL HAVE FALLEN ANOTHER 8 TO 10C WITH READINGS FROM -16C TO
-20C. THROUGH THE DAY MONDAY CLOUD COVER WILL OVERTAKE THE AREA
WITH H850 TEMPS SETTLING TOWARD -18C TO -20C REGION WIDE. MODELS
HAVE BEEN CONSISTENT WITH STEEPENING LAPSE RATES NEAR 15Z AND
STRONG MIXING THROUGH THE DAY...POTENTIAL FOR SNOW SHOWERS ACROSS
THE NORTHEAST WITH FLURRIES CENTRAL AND SOUTH. ALL IN ALL...MONDAY
IS LOOKING RATHER UNPLEASANT. POTENTIAL FOR 15 TO 25 MPH WINDS
WITH GUSTS TO NEAR 35 MPH AT TIMES. THIS WILL CAUSE PATCHY TO
AREAS BLOWING SNOW OVER MUCH OF THE NORTHEAST HALF OF THE AREA
WITH REDUCTIONS TO VISIBILITY. HEADLINES MAY BE NEEDED AGAIN ON
MONDAY FOR THE COMBINATION OF WIND...BLOWING SNOW...AND COLD. HAVE
EXPANDED THE POTENTIAL FOR LIGHT PRECIP AND BLOWING SNOW MONDAY
ACROSS THE AREA. HIGHS WILL RECOVER LITTLE FROM FRIGID MORNING
LOWS IN THE SINGLE DIGITS TO LOWER TEENS. BY AFTERNOON HIGHS NORTH
WILL REACH THE LOWER TEENS TO THE LOWER 20S IN THE SOUTHEAST. TO
TOP OFF THE WONDERFUL DAY...MINIMUM RECORD HIGHS LOOK LIKELY TO BE
SET AT MANY LOCATIONS...ONE WHICH HAS NOT BEEN SEEN SINCE THE
1890S AND MANY SINCE THE 1950S. IN FACT...OUR HIGHS MONDAY WOULD
STILL BE ABOUT 10 TO 15 DEGREES BELOW OUR COLDEST AVERAGE HIGHS
FOR THE NORMALLY COLDEST WINTER DAY OF THE YEAR...OR ABOUT 30
DEGREES BELOW OUR NORMAL FOR 11/17. WE HAVENT HAD HIGHS THIS COLD
SINCE EARLY MARCH OF 2014. TUESDAY WILL BEGIN QUITE COLD WITH A
RIDGE JUST EDGING INTO THE AREA BUT WARM BY AFTERNOON. QUICKLY
ANOTHER CLIPPER OVER THE NORTHERN PLAINS WILL MODERATE THE AIRMASS
WITH BRISK WEST WINDS DEVELOPING DURING THE DAY. TEMPS WILL RISE
INTO THE 20S. ANOTHER ARCTIC FRONT WILL DROP SOUTH INTO THE AREA
TUESDAY NIGHT BUT THE AIRMASS WILL NOT BE QUITE AS COLD AS THE
PREVIOUS. THE REMAINDER OF THE WEEK FEATURES A SERIES OF ARCTIC
SHORT WAVES ROTATING AROUND THE HUDSON BAY PARENT H500
LOW...PULLING ADDITIONAL COLD AIR TOWARD THE GREAT PLAINS. NEXT
WEEK WILL FEATURE DAYS WITH CLOUD COVER MIXED WITH SOME SUNSHINE
AND CHILLY READINGS. FORTUNATELY BY LATE IN THE EXTENDED...TOWARD
SATURDAY THE CROSS POLAR FLOW CUTS OFF...THE H500 RIDGE ACROSS THE
WEST COAST BREAKS DOWN AND MORE ZONAL FLOW RESULTS OVER THE
ROCKIES. THIS WILL CAUSE CHINOOK COMPRESSIONAL HEATING OVER THE
PLAINS AND MODERATE HIGHS TO ABOVE FREEZING. FROM WEDNESDAY
THROUGH FRIDAY HIGHS WILL APPROACH THE 30 DEGREE MARK WITH LOWS
MODERATING INTO THE TEENS OVER THE AREA. LITTLE PRECIPITATION IS
EXPECTED FOR MUCH OF THE PERIOD NEXT WEEK.
&&
.AVIATION...15/12Z
ISSUED AT 536 AM CST SAT NOV 15 2014
MVFR CONDITIONS WILL QUICKLY MOVE IN WITH THE SWATH OF SNOW LATE
THIS MORNING CONTINUE THROUGH THE AFTERNOON HOURS. HAVE IFR
CONDITIONS MENTIONED THIS AFTERNOON DURING THE HIGHER SNOWFALL
RATES ANTICIPATED. HIGHER CONFIDENCE TO MENTION IFR CIGS THIS
AFTERNOON AND KEPT MVFR CIGS THROUGH THE END OF THE TAF PERIOD.
SNOW SHOULD END BY 06Z TONIGHT...IF NOT SOONER FROM WEST TO EAST
HELPING TO IMPROVE VISIBILITY.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR ADAIR-ADAMS-APPANOOSE-AUDUBON-BLACK HAWK-BOONE-
BREMER-BUTLER-CALHOUN-CARROLL-CASS-CERRO GORDO-CLARKE-CRAWFORD-
DALLAS-DAVIS-DECATUR-EMMET-FRANKLIN-GREENE-GRUNDY-GUTHRIE-
HAMILTON-HANCOCK-HARDIN-HUMBOLDT-JASPER-KOSSUTH-LUCAS-MADISON-
MAHASKA-MARION-MARSHALL-MONROE-PALO ALTO-POCAHONTAS-POLK-
POWESHIEK-RINGGOLD-SAC-STORY-TAMA-TAYLOR-UNION-WAPELLO-WARREN-
WAYNE-WEBSTER-WINNEBAGO-WORTH-WRIGHT.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...PODRAZIK
AREA FORECAST DISCUSSION
NWS DES MOINES IA
303 AM CST SAT NOV 15 2014
.SHORT TERM /TODAY/...
ISSUED AT 303 AM CST SAT NOV 15 2014
NO MAJOR CHANGES WITH ONGOING FORECAST FOR THE FIRST
SIGNIFICANT SNOWFALL OF THE SEASON AS MODELS REMAIN IN GOOD
AGREEMENT WITH EXPECTED SNOW TODAY. USED A BLEND OF THE HRRR/HOPWRF
FOR TIMING OF PRECIP AND NAM/ECMWF TEMPS.
BROAD ISENTROPIC LIFT AND DECENT MOISTURE TRANSPORT DEVELOP OVER
WESTERN TO NORTHWEST IOWA THIS MORNING AND QUICKLY BLOSSOMS ACROSS
THE REMAINDER OF THE STATE THIS AFTERNOON. ONE MINOR CHANGE WAS
START THE SNOW A LITTLE SOONER THIS MORNING OVER THE WEST TO
NORTHWEST AS SNOW ALREADY DEVELOPING ALOFT AND SNOW SHOULD START
REACHING THE SURFACE BETWEEN 12-14Z THIS MORNING. THE 15.03Z HOPWRF
AND 15.05Z HRRR HAVE SNOW MOVING INTO THE WESTERN EDGES OF THE
FORECAST AREA BETWEEN 13-15Z. THE FORECAST SOUNDINGS ACROSS NORTHERN
IOWA BECOME COMPLETELY SATURATED BY 17-18Z TODAY AND THE STRONGER
OMEGA IS JUST AT THE TOP EDGE OF THE DENDRITIC LAYER BUT ENOUGH
OVERLAP TO SEE SOME DECENT FLAKES...AND THUS SLIGHTLY HIGHER SNOW
ACCUMULATION THIS AFTERNOON OVER NORTHERN IOWA. RAP IS A BIT LESS
WITH THE FORCING THAN THE NAM/GFS AND HAS SLIGHTLY LOWER SNOW
AMOUNTS GOING...BUT STILL DEPICTS ENOUGH SNOW TO WARRANT ADVISORY.
FURTHER SOUTH...SOUNDINGS NOT TOO DISSIMILAR THAN NORTHERN
IOWA...WITH THE MAIN DIFFERENCE BEING JUST SLIGHTLY LESSER FORCING
WITHIN THE DENDRITIC LAYER. THIS RESULTING IN LESS SNOW AMOUNTS OVER
THE SOUTHERN TWO-THIRDS OF THE FORECAST AREA.
LEANED TOWARD A BLEND OF THE WARMER NAM/ECMWF FOR TEMPERATURES
TODAY. THIS RESULTED IN SNOW RATIOS AROUND 17:1 TO 18:1 OVER NORTHERN
IOWA AND 15:1 TO 16:1 ACROSS THE SOUTH...BASED ON 925M TO 700MB
THICKNESS. HAVE 100 POPS GOING MUCH OF THE AFTERNOON WITH HIGH
CONFIDENCE ALL OF CENTRAL IOWA WILL BE SNOWING BY OR SHORTLY PAST
18Z. VERY LITTLE WIND TODAY BUT WITH THE FLUFFY SNOW TYPE EXPECTED
AND AT TIMES FALLING MODERATELY...THIS SHOULD BE ENOUGH TO CAUSE
SOME VISIBILITY RESTRICTION WITH A 6-9 KNOT WIND.
.LONG TERM /TONIGHT THROUGH FRIDAY/...
ISSUED AT 303 AM CST SAT NOV 15 2014
ACTIVE WEATHER WILL CONTINUE THROUGH THE WEEKEND AND EARLY NEXT WEEK
FOLLOWING TONIGHTS SYSTEM...ANOTHER INTENSE UPPER LEVEL LOW WILL
DROP SOUTH INTO THE NORTHERN GREAT LAKES SUNDAY NIGHT AND MONDAY
MORNING. TONIGHT...SYSTEM EXITING THE AREA TO THE EAST DURING THE
EVENING HOURS. BEST FORCING ALONG H500 AND SFC TROUGH NEAR 00Z
FOCUSING ON H700 BOUNDARY ACROSS NORTHERN IOWA. THROUGH 06Z THIS
H700 BOUNDARY PUSHES EAST WITH TROUGH RESULTING IN LESSENING FORCING
WEST OF I35 DURING THE LATE EVENING. BY 12Z BEST FORCING EAST OF THE
AREA WITH SOME RESIDUAL LIGHT SNOW/FLURRIES OVER THE NORTHEAST
ENDING QUICKLY WITH CLOUDS DEPARTING IN THE MORNING SUNDAY. SNOW
RATIOS OF 18 TO 20:1 AND EXPECTED QPF AMOUNT YIELD SNOWFALL
AMOUNTS OF UP TO ANOTHER 1.5 INCHES TONIGHT DURING THE EVENING AND
OVERNIGHT HOURS. FORTUNATELY THE WINDS WILL BE LIGHT DURING THE
EVENT...SO BLOWING SNOW WILL NOT BE AN ISSUE TONIGHT. WITH
CLEARING BY MORNING...LOWS WILL QUICKLY FALL NORTHWEST AND WEST
INTO THE SINGLE DIGITS WITH TEENS I35 EAST. SUNDAY WILL INITIALLY
SEE SOME SUNSHINE BETWEEN WAVES BUT CLOUDS WILL INCREASE WEST
DURING THE AFTERNOON. WITH H850 TEMPS IN THE -10C TO -12C RANGE
AND WESTERLY WINDS...TEMPERATURES WILL BE TOLERABLE IN THE MID 20S
OVER MOST OF THE AREA. AN APPROACHING COLD FRONT WILL SPREAD
CLOUDS ACROSS THE REGION THROUGH EARLY EVENING. THE SECOND STRONG
H500 LOW WILL FORCE A BULGE OF COLD AIR QUICKLY SOUTHEAST INTO
WESTERN IOWA SUNDAY EVENING WITH RATHER STRONG COLD AIR ADVECTION
AND INCREASING WINDS ALOFT. BY 12Z H850 TEMPS WILL HAVE FALLEN
ANOTHER 8 TO 10C WITH READINGS FROM -16C TO -20C. THROUGH THE DAY
MONDAY CLOUD COVER WILL OVERTAKE THE AREA WITH H850 TEMPS SETTLING
TOWARD -18C TO -20C REGION WIDE. MODELS HAVE BEEN CONSISTENT WITH
STEEPENING LAPSE RATES NEAR 15Z AND STRONG MIXING THROUGH THE
DAY...POTENTIAL FOR SNOW SHOWERS ACROSS THE NORTHEAST WITH
FLURRIES CENTRAL AND SOUTH. ALL IN ALL...MONDAY IS LOOKING RATHER
UNPLEASANT. POTENTIAL FOR 15 TO 25 MPH WINDS WITH GUSTS TO NEAR 35
MPH AT TIMES. THIS WILL CAUSE PATCHY TO AREAS BLOWING SNOW OVER
MUCH OF THE NORTHEAST HALF OF THE AREA WITH REDUCTIONS TO
VISIBILITY. HEADLINES MAY BE NEEDED AGAIN ON MONDAY FOR THE
COMBINATION OF WIND...BLOWING SNOW...AND COLD. HAVE EXPANDED THE
POTENTIAL FOR LIGHT PRECIP AND BLOWING SNOW MONDAY ACROSS THE
AREA. HIGHS WILL RECOVER LITTLE FROM FRIGID MORNING LOWS IN THE
SINGLE DIGITS TO LOWER TEENS. BY AFTERNOON HIGHS NORTH WILL REACH
THE LOWER TEENS TO THE LOWER 20S IN THE SOUTHEAST. TO TOP OFF THE
WONDERFUL DAY...MINIMUM RECORD HIGHS LOOK LIKELY TO BE SET AT MANY
LOCATIONS...ONE WHICH HAS NOT BEEN SEEN SINCE THE 1890S AND MANY
SINCE THE 1950S. IN FACT...OUR HIGHS MONDAY WOULD STILL BE ABOUT
10 TO 15 DEGREES BELOW OUR COLDEST AVERAGE HIGHS FOR THE NORMALLY
COLDEST WINTER DAY OF THE YEAR...OR ABOUT 30 DEGREES BELOW OUR
NORMAL FOR 11/17. WE HAVENT HAD HIGHS THIS COLD SINCE EARLY MARCH
OF 2014. TUESDAY WILL BEGIN QUITE COLD WITH A RIDGE JUST EDGING
INTO THE AREA BUT WARM BY AFTERNOON. QUICKLY ANOTHER CLIPPER OVER
THE NORTHERN PLAINS WILL MODERATE THE AIRMASS WITH BRISK WEST
WINDS DEVELOPING DURING THE DAY. TEMPS WILL RISE INTO THE 20S.
ANOTHER ARCTIC FRONT WILL DROP SOUTH INTO THE AREA TUESDAY NIGHT
BUT THE AIRMASS WILL NOT BE QUITE AS COLD AS THE PREVIOUS. THE
REMAINDER OF THE WEEK FEATURES A SERIES OF ARCTIC SHORT WAVES
ROTATING AROUND THE HUDSON BAY PARENT H500 LOW...PULLING
ADDITIONAL COLD AIR TOWARD THE GREAT PLAINS. NEXT WEEK WILL
FEATURE DAYS WITH CLOUD COVER MIXED WITH SOME SUNSHINE AND CHILLY
READINGS. FORTUNATELY BY LATE IN THE EXTENDED...TOWARD SATURDAY
THE CROSS POLAR FLOW CUTS OFF...THE H500 RIDGE ACROSS THE WEST
COAST BREAKS DOWN AND MORE ZONAL FLOW RESULTS OVER THE ROCKIES.
THIS WILL CAUSE CHINOOK COMPRESSIONAL HEATING OVER THE PLAINS AND
MODERATE HIGHS TO ABOVE FREEZING. FROM WEDNESDAY THROUGH FRIDAY
HIGHS WILL APPROACH THE 30 DEGREE MARK WITH LOWS MODERATING INTO
THE TEENS OVER THE AREA. LITTLE PRECIPITATION IS EXPECTED FOR MUCH
OF THE PERIOD NEXT WEEK.
&&
.AVIATION...15/06Z
ISSUED AT 1121 PM CST FRI NOV 14 2014
BROAD AREA OF SN WILL PUSH EAST INTO SITES BEGINNING AFTER 12Z. SN
WILL PERSIST AT SITES THROUGH MAJORITY OF PERIOD. CEILINGS AND
VISIBILITIES WILL DROP TO MVFR AND TO IFR AT TIMES...ESPECIALLY
WITH FALLING SNOW. SYSTEM WILL PUSH QUICKLY EAST AND MAY SEE
VISIBILITIES IMPROVE AT WESTERN SITES...KFOD/KDSM BY END OF
PERIOD BUT LOW MVFR OR IFR CEILINGS WILL REMAIN.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR ADAIR-ADAMS-APPANOOSE-AUDUBON-BLACK HAWK-BOONE-
BREMER-BUTLER-CALHOUN-CARROLL-CASS-CERRO GORDO-CLARKE-CRAWFORD-
DALLAS-DAVIS-DECATUR-EMMET-FRANKLIN-GREENE-GRUNDY-GUTHRIE-
HAMILTON-HANCOCK-HARDIN-HUMBOLDT-JASPER-KOSSUTH-LUCAS-MADISON-
MAHASKA-MARION-MARSHALL-MONROE-PALO ALTO-POCAHONTAS-POLK-
POWESHIEK-RINGGOLD-SAC-STORY-TAMA-TAYLOR-UNION-WAPELLO-WARREN-
WAYNE-WEBSTER-WINNEBAGO-WORTH-WRIGHT.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...AWB
AREA FORECAST DISCUSSION
NWS GOODLAND KS
210 PM MST SAT NOV 15 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 210 PM MST SAT NOV 15 2014
THE UPPER TROUGH AXIS MOVES SOUTH ACROSS THE CENTRAL PLAINS TONIGHT
AND SUNDAY WITH NORTHWEST FLOW FOLLOWING. SURFACE HIGH PRESSURE
WILL BUILD SOUTHEAST INTO THE CENTRAL PLAINS THROUGH THIS TIME.
PLAN TO GO WITH CHANCE AND LIKELY POPS TONIGHT ACROSS THE FA AS
DYNAMICS AND MOISTURE MOVE FROM NORTH TO SOUTH. THE DYNAMICS MOVE
INTO THE SOUTHWEST PORTION OF THE FA AFTER 06Z AND SO WILL SHIFT
LIKELY POPS OVER THE EXTREME SOUTHWEST AFTER MIDNIGHT WITH
DECREASING POPS TO THE NORTH. MOISTURE IS LIMITED WITH THIS SYSTEM
SO WILL KEEP SNOW AMOUNTS ON THE LIGHT SIDE OR A FEW TENTHS OF AN
INCH. THE SOUTHWEST WILL HAVE THE BEST CHANCE OF ACCUMULATING SNOW
WITH AROUND A HALF INCH POSSIBLE THERE.
MIN TEMPERATURES WILL FALL INTO THE SINGLE DIGITS OVERNIGHT AND WITH
NORTHWEST WIND SOME VERY COLD WIND CHILL TEMPERATURES WILL BE
REACHED. WIND CHILL TEMPERATURES DROP BELOW WIND CHILL ADVISORY
CRITERIA TONIGHT AND SUNDAY MORNING ACROSS THE NORTH AND WEST ZONES.
PLAN TO ISSUE A WIND CHILL ADVISORY TO COVER THIS. SEE DETAILS
BELOW. MAX TEMPERATURES SUNDAY SHOULD RISE TO THE UPPER 20S WITH
TEMPERATURES NEAR 30 OVER THE SOUTHEAST ZONES.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 210 PM MST SAT NOV 15 2014
SEVERAL DRY DAYS ARE EXPECTED FOR THE ENTIRE FORECAST AREA GOING
INTO THE BEGINNING OF NEXT WEEK. THE TRI STATE REGION WILL BE IN
BETWEEN A BROAD/DEEP 500 MB TROUGH THAT SETS UP OVER THE EASTERN
PORTION OF THE COUNTRY SUNDAY NIGHT INTO MONDAY...AND A BUILDING H5
RIDGE OVER THE WESTERN HALF OF THE COUNTRY. RIDGE DOES SHIFT
EASTWARD INTO THE ROCKIES BY MIDWEEK..WITH 500/700 MB TROUGH COMING
OFF THE PACIFIC AND THRU RIDGE...INTO ROCKIES LATE FRIDAY INTO
SATURDAY.
DOWN TO THE SURFACE...HIGH PRESSURE WILL BE MOST PREVALENT DURING
THIS TIMEFRAME. ONLY CHANCE FOR PRECIPITATION BEFORE NEXT WEEKEND
WILL BE ON WEDNESDAY AS FRONTAL BOUNDARY/TROUGH SHIFTS OFF THE
ROCKIES AND EASTWARD TO THE MISSISSIPPI VALLEY. WITH HIGH PRESSURE
SE OF THE AREA DURING THIS TIME AND BROAD WNW FLOW...LITTLE QPF
POTENTIAL...SO WILL HAVE DRY. THE NEXT CHANCE FOR PRECIPITATION WILL
BE AT THE END OF NEXT WEEK WHEN MID LEVEL SHORTWAVE MOVES EAST OFF
THE PACIFIC. DRY AIR OUT AHEAD OF IT...COMBINED WITH ITS TRIP THRU
THE ROCKIES...WILL LIMIT QPF POTENTIAL BUT OUTSIDE CHANCE OF A FEW
LATE DAY SHOWERS.
WITH LACK OF ANY APPRECIABLE RAIN OR SNOW NEXT WEEK...THE MAIN
FOCUS WILL BE SHIFT IN TEMPERATURES. WITH 850/925 MB TEMPS RANGING
FROM -2C TO -4C ON MONDAY...UP TO +9C TO +12C ON FRIDAY INTO
SATURDAY...THE FORECAST AREA WILL SEE BELOW NORMAL TEMPS SHIFTING TO
ABOVE NORMAL READINGS ESPECIALLY DURING THE DAY. TRI STATE REGION
WILL SEE HIGHS NEAR 30F ON MONDAY TO MID 40S BY MIDWEEK TO ALMOST
MID 50S FOR THE END OF NEXT WEEK. THIS WOULD GIVE WEDNESDAY INTO
SATURDAY WITH HIGHS 5 TO 10 DEGREES ABOVE NORMAL. WITH HIGH PRESSURE
MOST PREVALENT...CLEAR SKIES AT NIGHT WILL HAVE OVERNIGHT LOWS
RANGING FROM THE TEENS TO START THE WEEK...TO THE 20S FOR THE REST
OF THE TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1030 AM MST SAT NOV 15 2014
CIGS ARE PROGRESSIVELY LOWERING AT KGLD AND CONTINUE MVFR AT KMCK
AT MIDDAY AS THE UPPER TROUGH MOVES INTO THE NORTHERN AND CENTRAL
PLAINS TODAY. THE SREF AND HRRR BRING A SWATH OF LIGHT SNOW INTO
THE ARE THIS AFTERNOON WHICH SHOULD IMPACT BOTH TERMINALS WITH
MVFR CONDITIONS. LIGHT SNOW SHOULD END AT BOTH SITES EARLY THIS
EVENING WITH VFR CONDITIONS OCCURING BEHIND THE COLD FRONT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND CHILL ADVISORY FROM 9 PM MST /10 PM CST/ THIS EVENING TO 9
AM MST /10 AM CST/ SUNDAY FOR KSZ001>003-013.
CO...WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 9 AM MST SUNDAY
FOR COZ090-091.
NE...WIND CHILL ADVISORY FROM 9 PM MST /10 PM CST/ THIS EVENING TO 9
AM MST /10 AM CST/ SUNDAY FOR NEZ079>081.
&&
$$
SHORT TERM...FS
LONG TERM...JN
AVIATION...FS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1035 AM MST SAT NOV 15 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 404 AM MST SAT NOV 15 2014
MAIN FORECAST CONCERN WILL BE WINTER WEATHER EVENT OCCURRING
THROUGH TONIGHT. SATELLITE CONTINUING TO SHOW AN AMPLIFIED PATTERN
FROM THE EASTERN PACIFIC INTO EASTERN NORTH AMERICA. CURRENTLY
NEARLY ZONAL FLOW OVER OUR AREA WITH MULTIPLE SMALL SCALE WAVES
EMBEDDED WITHIN THAT FLOW. STRONG...COLD AND RATHER COMPLEX UPPER
TROUGH IS MOVING THROUGH THE NORTH CENTRAL OF THE COUNTRY.
SATELLITE ALSO SHOWING DRY MID LEVEL AIR MASS IN PLACE AHEAD OF
INCOMING NORTHERN TROUGH. ANOTHER STRONG COLD FRONT IS APPROACHING
FROM THE NORTH.
AT JET LEVEL...MODELS LOOKED LIKE THEY INITIALIZED FINE. AT MID
LEVELS...THE GFS WAS DOING A LITTLE BETTER THAN THE ECMWF AND
CANADIAN. THE SREF WAS DOING THE BEST AT THE SURFACE. ALL THE
MODELS WERE OKAY ON THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...THE DAY STARTS OUT WITH AREA IN SUBSIDENCE FROM
DEPARTING JET. AFTER THIS MODELS DISAGREE WHERE THE MAIN JET
ENERGY WILL BE THROUGH THE REST OF THE PERIOD. BY 18Z IT LOOKS
LIKE A LEFT FRONT QUADRANT WILL BEGIN AFFECTING THE AREA. BY LATE
IN THE AFTERNOON INTO THE EVENING...THERE MAY BE A RIGHT REAR
QUADRANT ACROSS THE SOUTHEASTERN PORTION OF THE AREA. AFTER THAT
THE JET IS WELL SOUTH.
CURRENTLY INITIAL SHORTWAVE TROUGH IS MOVING THROUGH AND PRODUCING
LIGHT SNOW OVER SOUTHERN AND EASTERN SECTIONS. MODELS HAVE A GOOD
HANDLE ON THIS INITIAL SHORTWAVE TROUGH. CURRENT RADAR SHOWS THAT
THE MOST INTENSE SNOWFALL IS TO THE SOUTH OF AREA AND MOVING
THROUGH RATHER QUICKLY. ALL NIGHT THE HRRR HAS BEEN CATCHING THE
CURRENT RADAR TRENDS EXTREMELY WELL AND IT ALSO MATCHES UP WELL
WITH THE ABOVE MENTIONED MID AND UPPER LEVEL LIFT. OTHER OUTPUT IS
TOO FAR NORTH WITH THE PRECIPITATION SHIELD. SO WILL LEAN HEAVILY
ON THE HRRR FOR PRECIPITATION EARLY ON AND THEN TREND MORE TOWARD
THE CANADIAN/ECMWF AFTER THAT.
SO LITTLE TO NO SNOW FALL WILL END UP FALLING OVER THE WESTERN
HALF TO TWO THIRDS THIS MORNING WITH MOST OF THE SNOW OCCURRING IN
THE EASTERN SIX COUNTIES THROUGH MID MORNING. UPSTREAM SATELLITE
IS SHOWING A CLEARING TREND BEHIND THIS EXITING SHORTWAVE AND A
DRY AIR MASS IN ADVANCE OF THE NEXT SHORTWAVE TROUGH. AFTER THE
SNOW ENDS THIS MORNING...THE NEXT BATCH OF LIGHT SNOW WILL DEVELOP
TO OUR NORTH AND NORTHWEST BY LATE IN THE MORNING TO EARLY
AFTERNOON. THIS AREA THEN MOVES ACROSS THE AREA THROUGH THE REST
OF THE NIGHT WITH THE MOST SNOWFALL OCCURRING BEFORE MIDNIGHT. IT
IS POSSIBLE THAT SOME LOCATIONS MAY NOT SEE ANY SNOW UNTIL LATER
THIS AFTERNOON TO EARLY THIS EVENING.
MODELS...ESPECIALLY THE GFS...TEND TO BE TOO DEEP WITH THE
MOISTURE AND THEREFORE OVERPRODUCES PRECIPITATION. THE DRIER AIR
MASS UPSTREAM MAKES SENSE SINCE MOISTURE IN THE WESTERLY FLOW
ALOFT IS GETTING WRUNG BY THE HIGHER TERRAIN OVER COLORADO. SO PER
THE REASONING GIVEN ABOVE...SNOWFALL AMOUNTS WILL BE MUCH LIGHTER
THAN PREVIOUSLY EXPECTED WITH TOTAL AMOUNTS NOW ANTICIPATED TO BE
AROUND AN INCH OR LESS. IT IS ALSO POSSIBLE THAT WHEN THE COLD
FRONT MOVES THROUGH LATER TODAY...THAT LITTLE IF ANY SNOW WILL BE
ON THE GROUND. ALSO CONSIDERING WHAT LITTLE SNOW HAS ALREADY
FALLEN AND THAT THERE WILL BE A SIGNIFICANT LULL BEFORE THE NEXT
SNOWFALL STARTS...HAVE DECIDED TO CANCEL THE WINTER WEATHER
ADVISORY. IF SNOWFALL ENDS UP BEING WORSE THAN CURRENTLY
EXPECTED...THEN A MORE SHORT TERM ADVISORY CAN BE ISSUED TO HANDLE
THAT SINCE NOTHING IS GOING ON AT THIS TIME.
NOW FOR TEMPERATURES. JUST LIKE LAST NIGHT...MODELS ARE TOO COOL
WITH THE CURRENT TEMPERATURES DUE TO CLOUD COVER AND CONTINUED
WARM AIR ADVECTION. FRONT IS ALSO EXPECTED TO ARRIVE LATER AND
WILL NOT MOVE THROUGH THE EASTERN PORTION OF THE AREA UNTIL THIS
AFTERNOON. THERE ALSO MAY BE ENOUGH BREAKS IN THE CLOUD COVER TO
ALLOW SOME SUNSHINE TO OCCUR. A LOT OF THE OUTPUT IS SAYING
WARMER AND TRENDED IN THAT DIRECTION.
SUNDAY/SUNDAY NIGHT...DRY CONDITIONS EXPECTED THROUGH THE PERIOD.
SHOULD SEE A DECENT AMOUNT OF SUN WITH WINDS BEING MOSTLY FROM A
DOWNSLOPE DIRECTION. MODELS ARE SHOW TEMPERATURES WARMER THAN
YESTERDAY. MODELS HAVE HAD A RECENT COOL BIAS AS WELL. SO WENT
NEAR THE WARMER GUIDANCE.
MONDAY/MONDAY NIGHT...STRONG UPPER SYSTEM DIGS INTO THE NORTH
CENTRAL PORTION OF THE COUNTRY JUST BEFORE AND DURING THIS PERIOD.
THIS PUSHES ANOTHER COLD FRONT THROUGH THE AREA AND SHOULD MAKE
FOR COOLER TEMPERATURES COMPARED TO SUNDAY MAXES. HOWEVER...THERE
IS A BIG DIFFERENCE IN THE AMOUNT OF COOLING INDICATED BY THE
MODELS. DID NOT GO WITH THE COLDEST GUIDANCE BUT TRENDED IN THE
COLDER DIRECTION.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 404 AM MST SAT NOV 15 2014
COMPARING TONIGHTS MODELS RUN TO LAST NIGHTS THE LONG WAVE RIDGE
OVER THE WEST COAST OF THE UNITED STATES WILL STILL MOVE EAST AND BE
LOCATED OVER THE ROCKIES BY FRIDAY. HOWEVER... UNLIKE LAST NIGHTS
RUN... WHERE THE RIDGE LOOKED LIKE IT WOULD FLATTEN... IT NOW
SEEMS IT WILL MAINTAIN ITS AMPLITUDE. THIS WILL PRODUCE A
PREDOMINATELY NORTHWESTERN UPPER LEVEL FLOW OVER THE TRI-STATE
AREA DURING THE EXTENDED.
YESTERDAYS QUESTION WAS WHEN WILL THE NEXT FRONT PASS OVER THE AREA.
TONIGHTS RUN OF THE GFS... NAVGEM AND ECMWF ARE IN BETTER AGREEMENT
ON THIS FRONT COMPARED TO LAST NIGHTS RUN. THEY ALL HAVE THE FRONT
PASSING OVER THE AREA ON THE 19TH BETWEEN 00Z AND 06Z. THEY ALSO
SHOW THIS SYSTEM TO BE A DRY ONE AND WILL HAVE LITTLE TO NO EFFECT
ON THE TEMPERATURES. IT DOES SHOW A SHIFT IN THE WINDS FOLLOWED BY
LIGHT WINDS AS HIGH PRESSURE BUILDS IN BEHIND IT FOR THE REST OF THE
EXTENDED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1030 AM MST SAT NOV 15 2014
CIGS ARE PROGRESSIVELY LOWERING AT KGLD AND CONTINUE MVFR AT KMCK
AT MIDDAY AS THE UPPER TROUGH MOVES INTO THE NORTHERN AND CENTRAL
PLAINS TODAY. THE SREF AND HRRR BRING A SWATH OF LIGHT SNOW INTO
THE ARE THIS AFTERNOON WHICH SHOULD IMPACT BOTH TERMINALS WITH
MVFR CONDITIONS. LIGHT SNOW SHOULD END AT BOTH SITES EARLY THIS
EVENING WITH VFR CONDITIONS OCCURING BEHIND THE COLD FRONT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...BDW/BULLER
AVIATION...FS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
447 AM MST SAT NOV 15 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 404 AM MST SAT NOV 15 2014
MAIN FORECAST CONCERN WILL BE WINTER WEATHER EVENT OCCURRING
THROUGH TONIGHT. SATELLITE CONTINUING TO SHOW AN AMPLIFIED PATTERN
FROM THE EASTERN PACIFIC INTO EASTERN NORTH AMERICA. CURRENTLY
NEARLY ZONAL FLOW OVER OUR AREA WITH MULTIPLE SMALL SCALE WAVES
EMBEDDED WITHIN THAT FLOW. STRONG...COLD AND RATHER COMPLEX UPPER
TROUGH IS MOVING THROUGH THE NORTH CENTRAL OF THE COUNTRY.
SATELLITE ALSO SHOWING DRY MID LEVEL AIR MASS IN PLACE AHEAD OF
INCOMING NORTHERN TROUGH. ANOTHER STRONG COLD FRONT IS APPROACHING
FROM THE NORTH.
AT JET LEVEL...MODELS LOOKED LIKE THEY INITIALIZED FINE. AT MID
LEVELS...THE GFS WAS DOING A LITTLE BETTER THAN THE ECMWF AND
CANADIAN. THE SREF WAS DOING THE BEST AT THE SURFACE. ALL THE
MODELS WERE OKAY ON THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...THE DAY STARTS OUT WITH AREA IN SUBSIDENCE FROM
DEPARTING JET. AFTER THIS MODELS DISAGREE WHERE THE MAIN JET
ENERGY WILL BE THROUGH THE REST OF THE PERIOD. BY 18Z IT LOOKS
LIKE A LEFT FRONT QUADRANT WILL BEGIN AFFECTING THE AREA. BY LATE
IN THE AFTERNOON INTO THE EVENING...THERE MAY BE A RIGHT REAR
QUADRANT ACROSS THE SOUTHEASTERN PORTION OF THE AREA. AFTER THAT
THE JET IS WELL SOUTH.
CURRENTLY INITIAL SHORTWAVE TROUGH IS MOVING THROUGH AND PRODUCING
LIGHT SNOW OVER SOUTHERN AND EASTERN SECTIONS. MODELS HAVE A GOOD
HANDLE ON THIS INITIAL SHORTWAVE TROUGH. CURRENT RADAR SHOWS THAT
THE MOST INTENSE SNOWFALL IS TO THE SOUTH OF AREA AND MOVING
THROUGH RATHER QUICKLY. ALL NIGHT THE HRRR HAS BEEN CATCHING THE
CURRENT RADAR TRENDS EXTREMELY WELL AND IT ALSO MATCHES UP WELL
WITH THE ABOVE MENTIONED MID AND UPPER LEVEL LIFT. OTHER OUTPUT IS
TOO FAR NORTH WITH THE PRECIPITATION SHIELD. SO WILL LEAN HEAVILY
ON THE HRRR FOR PRECIPITATION EARLY ON AND THEN TREND MORE TOWARD
THE CANADIAN/ECMWF AFTER THAT.
SO LITTLE TO NO SNOW FALL WILL END UP FALLING OVER THE WESTERN
HALF TO TWO THIRDS THIS MORNING WITH MOST OF THE SNOW OCCURRING IN
THE EASTERN SIX COUNTIES THROUGH MID MORNING. UPSTREAM SATELLITE
IS SHOWING A CLEARING TREND BEHIND THIS EXITING SHORTWAVE AND A
DRY AIR MASS IN ADVANCE OF THE NEXT SHORTWAVE TROUGH. AFTER THE
SNOW ENDS THIS MORNING...THE NEXT BATCH OF LIGHT SNOW WILL DEVELOP
TO OUR NORTH AND NORTHWEST BY LATE IN THE MORNING TO EARLY
AFTERNOON. THIS AREA THEN MOVES ACROSS THE AREA THROUGH THE REST
OF THE NIGHT WITH THE MOST SNOWFALL OCCURRING BEFORE MIDNIGHT. IT
IS POSSIBLE THAT SOME LOCATIONS MAY NOT SEE ANY SNOW UNTIL LATER
THIS AFTERNOON TO EARLY THIS EVENING.
MODELS...ESPECIALLY THE GFS...TEND TO BE TOO DEEP WITH THE
MOISTURE AND THEREFORE OVERPRODUCES PRECIPITATION. THE DRIER AIR
MASS UPSTREAM MAKES SENSE SINCE MOISTURE IN THE WESTERLY FLOW
ALOFT IS GETTING WRUNG BY THE HIGHER TERRAIN OVER COLORADO. SO PER
THE REASONING GIVEN ABOVE...SNOWFALL AMOUNTS WILL BE MUCH LIGHTER
THAN PREVIOUSLY EXPECTED WITH TOTAL AMOUNTS NOW ANTICIPATED TO BE
AROUND AN INCH OR LESS. IT IS ALSO POSSIBLE THAT WHEN THE COLD
FRONT MOVES THROUGH LATER TODAY...THAT LITTLE IF ANY SNOW WILL BE
ON THE GROUND. ALSO CONSIDERING WHAT LITTLE SNOW HAS ALREADY
FALLEN AND THAT THERE WILL BE A SIGNIFICANT LULL BEFORE THE NEXT
SNOWFALL STARTS...HAVE DECIDED TO CANCEL THE WINTER WEATHER
ADVISORY. IF SNOWFALL ENDS UP BEING WORSE THAN CURRENTLY
EXPECTED...THEN A MORE SHORT TERM ADVISORY CAN BE ISSUED TO HANDLE
THAT SINCE NOTHING IS GOING ON AT THIS TIME.
NOW FOR TEMPERATURES. JUST LIKE LAST NIGHT...MODELS ARE TOO COOL
WITH THE CURRENT TEMPERATURES DUE TO CLOUD COVER AND CONTINUED
WARM AIR ADVECTION. FRONT IS ALSO EXPECTED TO ARRIVE LATER AND
WILL NOT MOVE THROUGH THE EASTERN PORTION OF THE AREA UNTIL THIS
AFTERNOON. THERE ALSO MAY BE ENOUGH BREAKS IN THE CLOUD COVER TO
ALLOW SOME SUNSHINE TO OCCUR. A LOT OF THE OUTPUT IS SAYING
WARMER AND TRENDED IN THAT DIRECTION.
SUNDAY/SUNDAY NIGHT...DRY CONDITIONS EXPECTED THROUGH THE PERIOD.
SHOULD SEE A DECENT AMOUNT OF SUN WITH WINDS BEING MOSTLY FROM A
DOWNSLOPE DIRECTION. MODELS ARE SHOW TEMPERATURES WARMER THAN
YESTERDAY. MODELS HAVE HAD A RECENT COOL BIAS AS WELL. SO WENT
NEAR THE WARMER GUIDANCE.
MONDAY/MONDAY NIGHT...STRONG UPPER SYSTEM DIGS INTO THE NORTH
CENTRAL PORTION OF THE COUNTRY JUST BEFORE AND DURING THIS PERIOD.
THIS PUSHES ANOTHER COLD FRONT THROUGH THE AREA AND SHOULD MAKE
FOR COOLER TEMPERATURES COMPARED TO SUNDAY MAXES. HOWEVER...THERE
IS A BIG DIFFERENCE IN THE AMOUNT OF COOLING INDICATED BY THE
MODELS. DID NOT GO WITH THE COLDEST GUIDANCE BUT TRENDED IN THE
COLDER DIRECTION.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 404 AM MST SAT NOV 15 2014
COMPARING TONIGHTS MODELS RUN TO LAST NIGHTS THE LONG WAVE RIDGE
OVER THE WEST COAST OF THE UNITED STATES WILL STILL MOVE EAST AND BE
LOCATED OVER THE ROCKIES BY FRIDAY. HOWEVER... UNLIKE LAST NIGHTS
RUN... WHERE THE RIDGE LOOKED LIKE IT WOULD FLATTEN... IT NOW
SEEMS IT WILL MAINTAIN ITS AMPLITUDE. THIS WILL PRODUCE A
PREDOMINATELY NORTHWESTERN UPPER LEVEL FLOW OVER THE TRI-STATE
AREA DURING THE EXTENDED.
YESTERDAYS QUESTION WAS WHEN WILL THE NEXT FRONT PASS OVER THE AREA.
TONIGHTS RUN OF THE GFS... NAVGEM AND ECMWF ARE IN BETTER AGREEMENT
ON THIS FRONT COMPARED TO LAST NIGHTS RUN. THEY ALL HAVE THE FRONT
PASSING OVER THE AREA ON THE 19TH BETWEEN 00Z AND 06Z. THEY ALSO
SHOW THIS SYSTEM TO BE A DRY ONE AND WILL HAVE LITTLE TO NO EFFECT
ON THE TEMPERATURES. IT DOES SHOW A SHIFT IN THE WINDS FOLLOWED BY
LIGHT WINDS AS HIGH PRESSURE BUILDS IN BEHIND IT FOR THE REST OF THE
EXTENDED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 440 AM MST SAT NOV 15 2014
MODELS ARE HAVING A HARD TIME RESOLVING ONGOING CONDITIONS. THEY
ARE TENDING TO OVERDUE LOW LEVEL CLOUD COVER AND PRECIPITATION.
WILL BE GOING WITH PERSISTENCE/CURRENT CONDITIONS AND THE BEST
MESOSCALE GUIDANCE FOR THE BEGINNING OF THIS FORECAST. FIRST
SHORTWAVE AND ASSOCIATED SNOWFALL HAS MOVED TO THE EAST OF BOTH
TAF SITES. SO WILL HAVE VFR CONDITIONS AND NO SNOWFALL AT BOTH
SITES UNTIL THIS AFTERNOON WHEN NEXT SHORTWAVE TROUGH MOVES IN.
MVFR CEILINGS WILL BE POSSIBLE AT BOTH SITES THIS AFTERNOON INTO
EARLY THIS EVENING. AFTER THAT VFR CONDITIONS WILL RETURN TO BOTH
SITES. A COLD FRONT WILL MOVE THROUGH LATE THIS MORNING INTO
EARLY THIS AFTERNOON AND WILL PRODUCE SUSTAINED WINDS OF 15 TO 20
KNOTS WITH GUSTS GETTING CLOSE TO 30 KNOTS. GUSTS WILL END EARLY
THIS EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...BDW/BULLER
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS TOPEKA KS
523 AM CST Sat Nov 15 2014
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 223 AM CST SAT NOV 15 2014
09Z Water vapor and profiler data show the lead shortwave beginning
to come out of the Rockies and into western KS. Regional radars
show a band of precip preceding the wave now moving into central KS.
So the forecast appears to be on track, kind of.
Models continue to show a progressive wave moving across the area
today and the best forcing and lift is expected to overspread north
central KS during the next 3 to 6 hours. By noon or shortly after,
the forcing diminishes and models show the vertical motion shifting
out of the area. There still does not appear to be much of a surface
reflection with the short wave that could enhance mesoscale forcing
either. There atmosphere does appear to be weakly unstable with some
conditional symmetric instability and even hints of upright
instability which could allow for a brief intensification to the
snowfall. There have been some lightning strikes over the central
Rockies with the wave. In general everything points to lower snow
amounts today due to no sustained forcing mechanism to maintain
precipitation. And given the track of the wave, which fits well with
the latest guidance, north central KS is more likely to see 1 to 3
inches while east central KS might be lucky to pick up an inch. Will
not make any changes to the advisory at this time. The biggest
impact could be a brief period of heavy snow in the convective
elements that restricts visibilities and quickly brings an inch or
so of snow.
Have bumped up highs today to around the freezing mark. While it is
not real strong, there is persistent low level warm air advection
with the southeast winds of 5 to 10 mph. If snowfall ends early in
the day and the clouds thin, highs could be a degree or two warmer.
Am not real concerned about mixed precip today as forecast soundings
maintain temps below freezing aloft. Its only at the surface where
temps warm above freezing and this is likely to happen once the
snowfall exits to the east and north. About the only concern I have
for a different precip type other than snow is for the potential of
light drizzle this afternoon. Low levels stay saturated with some
weak isentropic lift in the cloud. If drizzle (or freezing drizzle
depending on temps) were to happen, think it would occur after the
area of snow has ended due to a lose of forcing and deep vertical
motion.
For tonight, there remains some forcing as a more amplified wave
swings across NEB driving a cold front through the area. However by
this time models have a hard time keeping the column saturated. Have
kept some small chances going to account for the wave, but think any
snow would not amount to much. The one concern this evening would be
possible strengthening northwest winds behind the front. Models
suggest speed around 15 MPH are possible behind the front and any
snow that was falling could blow around some. Again think this may
be a marginal impact and last for a short period of time. Lows
tonight should fall into the teens as cold air moves in behind the
front.
.LONG TERM...(Sunday through Friday)
Issued at 223 AM CST SAT NOV 15 2014
Lingering flurries quickly come to an end early Sunday morning as
dry air continues to increase aloft with the upper forcing
exiting. A piece of energy from the main upper trough progresses
through Kansas during the afternoon as subsident air quickly
follows and scours cloud deck to the south. A secondary and colder
than previous 1040 MB surface high begins to spread into the CWA
as highs struggle into the 20s. Temps from this point on become
colder through Tuesday as the arctic airmass spreads across much
of the country. Coldest night thus far in the season will be on
Tuesday morning as all guidance points at record cold lows in the
single digits. A rebound in temps commences through the end of the
period as the surface high shifts east and warmer air advects
northward, boosting highs near 40 degrees Wednesday through
Friday. A poignant blocking ridge across the western CONUS will
prevail dry northwest flow aloft through Thursday with indication
from the GFS/ECMWF on the ridge beginning to break down Friday as
an upper trough enters the west coast.
&&
.AVIATION...(For the 12Z TAFs through 12Z Sunday Morning)
Issued at 523 AM CST SAT NOV 15 2014
An area of snow continues to move northeast towards the terminals.
Based on radar, the snow may impact the airports 1-2 hours sooner
the the HRRR or RAP suggest. Have kept a tempo for IFR conditions
since the NAM and GFS show potential for upright instability and
brief periods of more intense snowfall. Otherwise think there is a
short window for accumulating snowfall. Main uncertainty with the
forecast are the CIGS. NAM MOS wants to keep a prolonged period of
MVFR conditions after the snow is expected to diminish. Based on
obs over southwest MO and northeast OK, this seems unlikely. Did
bring some MVFR CIGS back in after the FROPA. But this to should
not last long as dry air advects in from the northwest.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY until 6 PM CST this evening FOR
KSZ008>012-020>024-026-034>040-054>056-058-059.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GOODLAND KS
405 AM MST SAT NOV 15 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 404 AM MST SAT NOV 15 2014
MAIN FORECAST CONCERN WILL BE WINTER WEATHER EVENT OCCURRING
THROUGH TONIGHT. SATELLITE CONTINUING TO SHOW AN AMPLIFIED PATTERN
FROM THE EASTERN PACIFIC INTO EASTERN NORTH AMERICA. CURRENTLY
NEARLY ZONAL FLOW OVER OUR AREA WITH MULTIPLE SMALL SCALE WAVES
EMBEDDED WITHIN THAT FLOW. STRONG...COLD AND RATHER COMPLEX UPPER
TROUGH IS MOVING THROUGH THE NORTH CENTRAL OF THE COUNTRY.
SATELLITE ALSO SHOWING DRY MID LEVEL AIR MASS IN PLACE AHEAD OF
INCOMING NORTHERN TROUGH. ANOTHER STRONG COLD FRONT IS APPROACHING
FROM THE NORTH.
AT JET LEVEL...MODELS LOOKED LIKE THEY INITIALIZED FINE. AT MID
LEVELS...THE GFS WAS DOING A LITTLE BETTER THAN THE ECMWF AND
CANADIAN. THE SREF WAS DOING THE BEST AT THE SURFACE. ALL THE
MODELS WERE OKAY ON THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...THE DAY STARTS OUT WITH AREA IN SUBSIDENCE FROM
DEPARTING JET. AFTER THIS MODELS DISAGREE WHERE THE MAIN JET
ENERGY WILL BE THROUGH THE REST OF THE PERIOD. BY 18Z IT LOOKS
LIKE A LEFT FRONT QUADRANT WILL BEGIN AFFECTING THE AREA. BY LATE
IN THE AFTERNOON INTO THE EVENING...THERE MAY BE A RIGHT REAR
QUADRANT ACROSS THE SOUTHEASTERN PORTION OF THE AREA. AFTER THAT
THE JET IS WELL SOUTH.
CURRENTLY INITIAL SHORTWAVE TROUGH IS MOVING THROUGH AND PRODUCING
LIGHT SNOW OVER SOUTHERN AND EASTERN SECTIONS. MODELS HAVE A GOOD
HANDLE ON THIS INITIAL SHORTWAVE TROUGH. CURRENT RADAR SHOWS THAT
THE MOST INTENSE SNOWFALL IS TO THE SOUTH OF AREA AND MOVING
THROUGH RATHER QUICKLY. ALL NIGHT THE HRRR HAS BEEN CATCHING THE
CURRENT RADAR TRENDS EXTREMELY WELL AND IT ALSO MATCHES UP WELL
WITH THE ABOVE MENTIONED MID AND UPPER LEVEL LIFT. OTHER OUTPUT IS
TOO FAR NORTH WITH THE PRECIPITATION SHIELD. SO WILL LEAN HEAVILY
ON THE HRRR FOR PRECIPITATION EARLY ON AND THEN TREND MORE TOWARD
THE CANADIAN/ECMWF AFTER THAT.
SO LITTLE TO NO SNOW FALL WILL END UP FALLING OVER THE WESTERN
HALF TO TWO THIRDS THIS MORNING WITH MOST OF THE SNOW OCCURRING IN
THE EASTERN SIX COUNTIES THROUGH MID MORNING. UPSTREAM SATELLITE
IS SHOWING A CLEARING TREND BEHIND THIS EXITING SHORTWAVE AND A
DRY AIR MASS IN ADVANCE OF THE NEXT SHORTWAVE TROUGH. AFTER THE
SNOW ENDS THIS MORNING...THE NEXT BATCH OF LIGHT SNOW WILL DEVELOP
TO OUR NORTH AND NORTHWEST BY LATE IN THE MORNING TO EARLY
AFTERNOON. THIS AREA THEN MOVES ACROSS THE AREA THROUGH THE REST
OF THE NIGHT WITH THE MOST SNOWFALL OCCURRING BEFORE MIDNIGHT. IT
IS POSSIBLE THAT SOME LOCATIONS MAY NOT SEE ANY SNOW UNTIL LATER
THIS AFTERNOON TO EARLY THIS EVENING.
MODELS...ESPECIALLY THE GFS...TEND TO BE TOO DEEP WITH THE
MOISTURE AND THEREFORE OVERPRODUCES PRECIPITATION. THE DRIER AIR
MASS UPSTREAM MAKES SENSE SINCE MOISTURE IN THE WESTERLY FLOW
ALOFT IS GETTING WRUNG BY THE HIGHER TERRAIN OVER COLORADO. SO PER
THE REASONING GIVEN ABOVE...SNOWFALL AMOUNTS WILL BE MUCH LIGHTER
THAN PREVIOUSLY EXPECTED WITH TOTAL AMOUNTS NOW ANTICIPATED TO BE
AROUND AN INCH OR LESS. IT IS ALSO POSSIBLE THAT WHEN THE COLD
FRONT MOVES THROUGH LATER TODAY...THAT LITTLE IF ANY SNOW WILL BE
ON THE GROUND. ALSO CONSIDERING WHAT LITTLE SNOW HAS ALREADY
FALLEN AND THAT THERE WILL BE A SIGNIFICANT LULL BEFORE THE NEXT
SNOWFALL STARTS...HAVE DECIDED TO CANCEL THE WINTER WEATHER
ADVISORY. IF SNOWFALL ENDS UP BEING WORSE THAN CURRENTLY
EXPECTED...THEN A MORE SHORT TERM ADVISORY CAN BE ISSUED TO HANDLE
THAT SINCE NOTHING IS GOING ON AT THIS TIME.
NOW FOR TEMPERATURS. JUST LIKE LAST NIGHT...MODELS ARE TOO COOL
WITH THE CURRENT TEMPERATURES DUE TO CLOUD COVER AND CONTINUED
WARM AIR ADVECTION. FRONT IS ALSO EXPECTED TO ARRIVE LATER AND
WILL NOT MOVE THROUGH THE EASTERN PORTION OF THE AREA UNTIL THIS
AFTERNOON. THERE ALSO MAY BE ENOUGH BREAKS IN THE CLOUD COVER TO
ALLOW SOME SUNSHINE TO OCCUR. A LOT OF THE OUTPUT IS SAYING
WARMER AND TRENDED IN THAT DIRECTION.
SUNDAY/SUNDAY NIGHT...DRY CONDITIONS EXPECTED THROUGH THE PERIOD.
SHOULD SEE A DECENT AMOUNT OF SUN WITH WINDS BEING MOSTLY FROM A
DOWNSLOPE DIRECTION. MODELS ARE SHOW TEMPERATURES WARMER THAN
YESTERDAY. MODELS HAVE HAD A RECENT COOL BIAS AS WELL. SO WENT
NEAR THE WARMER GUIDANCE.
MONDAY/MONDAY NIGHT...STRONG UPPER SYSTEM DIGS INTO THE NORTH
CENTRAL PORTION OF THE COUNTRY JUST BEFORE AND DURING THIS PERIOD.
THIS PUSHES ANOTHER COLD FRONT THROUGH THE AREA AND SHOULD MAKE
FOR COOLER TEMPERATURES COMPARED TO SUNDAY MAXES. HOWEVER...THERE
IS A BIG DIFFERENCE IN THE AMOUNT OF COOLING INDICATED BY THE
MODELS. DID NOT GO WITH THE COLDEST GUIDANCE BUT TRENDED IN THE
COLDER DIRECTION.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 404 AM MST SAT NOV 15 2014
COMPARING TONIGHTS MODELS RUN TO LAST NIGHTS THE LONG WAVE RIDGE
OVER THE WEST COAST OF THE UNITED STATES WILL STILL MOVE EAST AND BE
LOCATED OVER THE ROCKIES BY FRIDAY. HOWEVER... UNLIKE LAST NIGHTS
RUN... WHERE THE RIDGE LOOKED LIKE IT WOULD FLATTEN... IT NOW
SEEMS IT WILL MAINTAIN ITS AMPLITUDE. THIS WILL PRODUCE A
PERDOMINATELY NORTHWESTERN UPPER LEVEL FLOW OVER THE TRI-STATE
AREA DURING THE EXTENDED.
YESTERDAYS QUESTION WAS WHEN WILL THE NEXT FRONT PASS OVER THE AREA.
TONIGHTS RUN OF THE GFS... NAVGEM AND ECMWF ARE IN BETTER AGREEMENT
ON THIS FRONT COMPARED TO LAST NIGHTS RUN. THEY ALL HAVE THE FRONT
PASSING OVER THE AREA ON THE 19TH BWTWEEN 00Z AND 06Z. THEY ALSO
SHOW THIS SYSTEM TO BE A DRY ONE AND WILL HAVE LITTLE TO NO EFFECT
ON THE TEMPERATURES. IT DOES SHOW A SHIFT IN THE WINDS FOLLOWED BY
LIGHT WINDS AS HIGH PRESSURE BUILDS IN BEHIND IT FOR THE REST OF THE
EXTENDED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1025 PM MST FRI NOV 14 2014
MONITOR FOR POTENTIAL WINTER PRECIP AT BOTH KGLD AND KMCK
TERMINALS DURING THE TAF PERIOD. HIGHEST CONFIDENCE IN LOWER
VIS/CIGS IS 09Z-15Z PERIOD...WHEN MVFR...POSSIBLY IFR WILL OCCUR
AS LIGHT SNOW DEVELOPS. COULD SEE A BRIEF PERIOD OF FREEZING
DRIZZLE AROUND 12-15Z...HOWEVER CONFIDENCE IS TOO LOW IN
COVERAGE/TIMING TO ADD MENTION. THERE SHOULD BE IMPROVEMENT IN
CONDITIONS BY MIDDAY...WITH ANOTHER ROUND OF SNOW BY LATE SATURDAY
AFTERNOON. THERE COULD BE BRIEF REDUCTIONS IN VIS/CIGS WITH THIS
SECOND BATCH OF SNOW...HOWEVER THERE ARE STILL TIMING AND COVERAGE
VARIATIONS BETWEEN MODELS WITH THIS SECOND ROUND OF SNOW...SO I
KEPT VFR CONDITIONS IN THE AFTERNOON/EVENING SATURDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...BDW/BULLER
AVIATION...DR
AREA FORECAST DISCUSSION
NWS PADUCAH KY
939 PM CST Sun Nov 16 2014
.UPDATE...
Issued at 937 CST SUN NOV 16 2014
Making some minor adjustments to snow totals, but overall the
package looks good. The heaviest precipitation band has set up
from Stoddard county in SEMO to the northwest half of McCracken
towards Henderson county to Spencer county. This has pretty much
been the story so far this evening.
The HRRR model depicts things pretty well and we expect that
heavier band to stay in place through about midnight, then the
band should actually shift to the north a bit as the main short
wave gets closer. This band then slides southeast through the
early morning hours.
Already had some 2+ inch amounts along the Wabash/Ohio River
areas and once the temperature drops to 32 the accumulations
start. The 32 degree line essentially runs from EVV to PAH and is
slowly moving southeast.
&&
.SHORT TERM...(Tonight through Tuesday night)
Issued at 134 PM CST SUN NOV 16 2014
Confidence in increasing that there will be a fairly significant
snow event along the Ohio River and back into extreme southeast
Missouri. 12z GFS, in particular has honed in on a precip max
along that axis for several runs now, and thermal profiles suggest
that axis will likely correspond to where the initial snow/mix line
will set up early this evening. Expecting very close to .40 inches
liquid QPF, so will increase snow projections into the 3-5 inch
range. Have already upgraded to warning headlines along the Ohio
River for tonight. See no need for further adjustments at this
time. Still looking for all snow northwest of the warning area,
but QPF will likely not be quite as high. Will need to monitor
though, because have already heard of at least one report of 3.5
inches out to our west in the SGF CWA. Will stick with the
advisory in our nw half for the time being. Still lots of
uncertainties concerning precip type and the timing of the
transition from rain/sleet over to snow, most likely around
or after the midnight time frame far southeast locations. Believe
there will still be enough moisture left after the transition
over to snow later tonight for an inch or so to accumulate before
the precip comes to an end around dawn Monday. Thus, will
continue with the Winter Weather Advisory for the rest of the CWA
surrounding the warning area.
Next big story lies with the bitterly cold Arctic air that will
follow early in the week. Blustery winds gusting over 20 mph on
Monday may cause some blowing or drifting of any snow that is on
the ground and hold daytime temps nearly steady in the 20s. Will
then challenge record low temps Monday night as reading fall down
into the 10 to 15 degree range. Wind chill values could be near
zero by the time many awake and head out on Tuesday.
.LONG TERM...(Wednesday through Sunday)
Issued at 320 PM CST SUN NOV 16 2014
Surface high pressure over the southeast U.S. will keep our region
dry Tuesday night into Wednesday, and a return of south to southwest
winds will help temperatures moderate a little from the very cold
temperatures early in the work week. Models continue to show a weak
dry cold front moving across the middle Mississippi and lower Ohio
valleys Wednesday into Wednesday night. This will bring another
shot of colder air, with highs Thursday and Friday again dropping
back a couple to several degrees.
For Thursday night and beyond, models continue to be all over the
place. GFS brings in a shot of precip late Thursday into Thursday
night, then another shot Saturday and through the weekend. ECMWF
bring precip into the area late Friday and continues through the
weekend. GEM keeps us dry through 12z Saturday, but does match up
well to the GFS at that time. Went ahead and kept some small PoPs
in across much of the PAH forecast area Thursday night for some
light snow. By Saturday, when models seems to be lining up, went
with slight chance pops for Saturday for most of the PAH fa, with
increasing chances Saturday night into Sunday. Fortunately, it
looks like temperatures will be warm enough that it will just be
rain through the weekend. High by Sunday will only be a few degrees
below normal.
&&
.AVIATION...
Issued at 320 PM CST SUN NOV 16 2014
Conditions will continue to deteriorate into tonight as developing
drizzle/light rain switches over to snow at all TAF sites. Low
VFR/MVFR conditions will drop into the IFR range for much of the
overnight with light to moderate snowfall. Snow will taper off late
tonight, with conditions improving to VFR around daybreak. Light
and variable winds will become northwest at 5 to 10 kts overnight,
then increase to 10 to 20 kts with high gusts around 13z.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WARNING until 6 AM CST Monday FOR ILZ087-089>094.
WINTER WEATHER ADVISORY until 6 AM CST Monday FOR ILZ075>078-
080>086-088.
MO...WINTER STORM WARNING until 6 AM CST Monday FOR MOZ110>112-114.
WINTER WEATHER ADVISORY until 6 AM CST Monday FOR MOZ076-086-087-
100-107>109.
IN...WINTER STORM WARNING until 6 AM CST Monday FOR INZ085>088.
WINTER WEATHER ADVISORY until 6 AM CST Monday FOR INZ081-082.
KY...WINTER STORM WARNING until 6 AM CST Monday FOR KYZ003>005-007-
010-014-015-018-019.
WINTER WEATHER ADVISORY until 6 AM CST Monday FOR KYZ001-002-006-
008-009-011>013-016-017-020>022.
&&
$$
UPDATE...PS
SHORT TERM...GM
LONG TERM...RST
AVIATION...RST
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
839 PM EST Sun Nov 16 2014
...Forecast Update...
Issued at 840 PM EST Nov 16 2014
Had another ACARS soundings showing a thinner warm layer aloft, but
still enough to melt the ice and then allow for some re-freezing, as
we have been getting a few more sleet reports. Observations deeper
into the cold over southern Indiana are showing all snow. Latest
water vapor loop shows the area of enhanced lift associated with the
right rear quadrant of an upper jet to our north. A potent
shortwave, now over Oklahoma, will merge with a longer wave trough
dropping down over the Central Plains to enhance precip further
overnight.
The warm nose may briefly re-exert it`s influence northward over the
next few hours before the cold air smashes through here late
tonight. The timing mentioned in our web briefings still looks
reasonable as well as the totals. Will add in better chances for
sleet, but overall this package is not a big change.
Issued at 620 PM EST Nov 16 2014
Had some good ACARS soundings in an hour or two ago, and basically
matched these up with the latest RUC temps aloft. Have used this
model for the next few hours to generate the transition zone for
rain to rain/snow mix to all snow. These changes did not change the
overall snow totals significantly, so no need to change the
advisory/warning area at this point. Will continue to monitor
multiple sources and adjust the forecast as needed through the
evening hours.
.SHORT TERM (Now through Monday Night)...
Issued at 340 PM EST Sun Nov 16 2014
...Accumulating Snows Likely Tonight into Monday...
Overview
--------
The short term period will feature a broad trough across much of the
CONUS. A strong PV anomaly is currently getting ready to enter the
southern Plains and will quickly slide east toward the mid
Mississipi Valley toward dawn. Ahead of this feature, surface
cyclogenesis is already occurring over the lower Mississippi. This
system will quickly lift NE and deepen as it slides by to our east
on Monday. Moisture is already spreading north into the region, and
will continue into tonight ahead of these slowly phasing systems.
This deep moisture will interact with increasingly colder
temperature profiles and produce a period of wintery weather across
the Ohio Valley.
Model Preference
----------------
There has been a wide model discrepancy with respect to thermal
profiles below 700 mb leading up to this event, overall leading to
low confidence. We did get a trend toward some better agreement with
the 12z runs, so decided to blend mainly between the 12z NAM/GFS
temperature profiles. Do think the outcome of this event ultimately
hinges more on the lower mid levels than nearer the surface, however
did want to mention that surface temperatures are expected to hover
around or just above freezing until the heavier snow falls toward
dawn.
Sensible Weather and Impacts
----------------------------
Current radar does show the two separate storm systems nicely with
light rain over southern KY and mainly light snow overspreading
central IL/IN. We`ll watch through the evening hours as deeper
moisture slowly invades the area, however expect only light
precipitation and no real impacts initially. Southern Indiana could
see light accumulations as early as around sunset. Precipitation will
likely mix at times even across our north as temp profiles fluctuate
under varying degrees of saturation. Really not expecting the main
show to get going until we approach Midnight as system becomes more
organized, column becomes more saturated, and surface temps wet bulb
down toward more wintery precip conducive numbers.
A frontogenetically forced band of snow will then ride SW to NE
across our Warning area, pivoting to a more SSW to NNE orientation
through the night as the right entrance region of an upper level jet
slides overhead. This pivoting should actually enhance the
frontogenesis as well as keep the warm nose near the Ohio River.
Thereafter, the approaching PV anomaly begins to rapidly push the
system east with cold air crashing in in the low to mid levels. The
surface low will strengthen as it slides just to our east, providing
more deep moisture to interact with the cold air.
Since the warm layer aloft is going to drive this event, will
characterize how the overnight progresses by describing its
evolution through several geographic areas.
Southern Indiana (Winter Storm Warning 3-5" of Snow)
----------------------------------------------------
This area is expected to stay below freezing through the thermal
column, so all snow is expected other than a brief mix at onset.
This is expected to yield 3-5 inches by Monday morning, with the
heaviest snow falling between Midnight and 7 AM EST. Impacts to
roads and travel are expected.
Right Along the Ohio River (Winter Weather Advisory 2-3" Snow)
--------------------------------------------------------------
This area is the northern portion of the battleground between the
warm nose aloft. Expect to see mainly snow, however a few brief
periods of wintery mix including some sleet should cut down on
totals a bit. Expect all snow around and after Midnight EST.
Just South of the Ohio River (Winter Weather Advisory 1-3" Snow and
a mix)
-------------------------------------------------------------------
This area will be more see more of the warm air aloft for a longer
time and should cut down on snow totals. Could also see more
bouts of sleet with no impact. The city of Louisville will be right
underneath this battleground, so bust potential is high in this
transition zone. Much will depend on how quick the changeover
occurs. Expect change over between 1 and 4 AM EST.
Bluegrass Region North of I-64 (Winter Weather Advisory 2-4" Snow)
------------------------------------------------------------------
Mostly rain before 4 AM EST. An enhanced area of snow after 4 AM
EST, where deeper moisture mentioned above will be present as two
storm systems phase.
South Central Kentucky (Impact Based Winter Weather Advisory 1" or
less and a brief mix)
-----------------------------------------------------------------
Transition time and the amount of deep moisture left are in question
in this area, as well as rainfall`s effect on ability to accumulate.
Nevertheless, a quick shot of snow around the morning commute, and
the first snow of the year is enough to warrant the advisory.
.LONG TERM (Tuesday through Sunday)...
Issued at 335 PM EST Sun Nov 16 2014
Forecast thoughts in the long term period have not changed much for
this forecast issuance as most of the forecasting focus was on the
Winter Storm Warning/Advisories in the short term period. See the
following excerpts from the previous discussion with a few added
thoughts below.
Deep upper troffing digging from eastern Canada into the United
States, with occasional small reinforcing shots moving through the
flow, will keep us cold for much of the work week, with any
appreciable moderation in temperatures holding off until the weekend
and into next week. Most moisture associated with the upper trof
will stay bottled up to our north, so though it will be cold, it
will also be mostly on the drier side (not necessarily *completely*
dry), with some moisture return possible next weekend.
The models are a mess in the long term, especially Thursday through
Sunday. Models are having difficulty with various shortwaves diving
south across the Plains in an a broad digging upper level trough.
These shortwaves will eventually bring us precip during the latter
half of the week but when, how much, and what type all remain in
question.
The main story Tuesday through Wednesday will be the cold. Tuesday
night we will drop well into the teens. Depending on the location
and depth of any snowpack from tonight`s snowfall, a reading or two
in the single digits may not be out of the question in sheltered
areas from southeast Indiana into the northern Blue Grass. High
temperatures on Tuesday will only be in the lower and middle 20s,
which is about 30 degrees colder than normal!
Wednesday we may be able to moderate up to around 40 in southwest
low level flow between high pressure over Dixie and a cold front
crossing the Great Lakes, but that will be offset by winds gusting
to 25 mph and afternoon wind chills mostly in the 20s.
As mentioned earlier, Thursday through Sunday are tough to figure
out right now. Will lean toward the drier side of the forecast
envelope and keep PoPs small for now. Will bring MaxT`s well up into
the 40s by Saturday with the anticipated pattern change.
&&
.AVIATION (00Z TAF Update)...
Updated at 620 PM EST Sun Nov 16 2014
Winter conditions are on their way for the sites tonight. Cigs will
drop to LIFR or worse for most if not all the overnight period. Rain
ongoing now will transition over to snow, first between 04 and 07Z
at KSDF and later at the other two sites. Vsby will be worse once it
goes over to all snow, but have LIFR conditions persiste through mid
morning, when snow will start to exit off to the east and cigs will
rise slowly. Cannot rule out additional snow showers through the
afternoon and evening, as soundings don`t show much moisture, but
that moisture is in the ice crystal growth zone and there is some
instability as well. Winds will pick up from the west and northwest
through the day tomorrow as the cold air behind this system rushes
in.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WINTER STORM WARNING until Noon EST /11 AM CST/ Monday FOR
KYZ023-032.
WINTER WEATHER ADVISORY from 3 AM EST /2 AM CST/ to Noon EST /11
AM CST/ Monday FOR KYZ027-036-037-039>043-045>049-053>057-
061>065-070>072.
WINTER WEATHER ADVISORY until Noon EST /11 AM CST/ Monday FOR
KYZ024>026-028>031-033>035-038.
IN...WINTER STORM WARNING until Noon EST /11 AM CST/ Monday FOR
INZ076>079-083-084-089>092.
&&
$$
Update.........RJS
Short Term.....BJS
Long Term......AMS
Aviation.......RJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
622 PM EST Sun Nov 16 2014
...Updated Forecast and Aviation Discussions...
...Forecast Update...
Issued at 620 PM EST Nov 16 2014
Had some good ACARS soundings in an hour or two ago, and basically
matched these up with the latest RUC temps aloft. Have used this
model for the next few hours to generate the transition zone for
rain to rain/snow mix to all snow. These changes did not change the
overall snow totals significantly, so no need to change the
advisory/warning area at this point. Will continue to monitor
multiple sources and adjust the forecast as needed through the
evening hours.
.SHORT TERM (Now through Monday Night)...
Issued at 340 PM EST Sun Nov 16 2014
...Accumulating Snows Likely Tonight into Monday...
Overview
--------
The short term period will feature a broad trough across much of the
CONUS. A strong PV anomaly is currently getting ready to enter the
southern Plains and will quickly slide east toward the mid
Mississipi Valley toward dawn. Ahead of this feature, surface
cyclogenesis is already occurring over the lower Mississippi. This
system will quickly lift NE and deepen as it slides by to our east
on Monday. Moisture is already spreading north into the region, and
will continue into tonight ahead of these slowly phasing systems.
This deep moisture will interact with increasingly colder
temperature profiles and produce a period of wintery weather across
the Ohio Valley.
Model Preference
----------------
There has been a wide model discrepancy with respect to thermal
profiles below 700 mb leading up to this event, overall leading to
low confidence. We did get a trend toward some better agreement with
the 12z runs, so decided to blend mainly between the 12z NAM/GFS
temperature profiles. Do think the outcome of this event ultimately
hinges more on the lower mid levels than nearer the surface, however
did want to mention that surface temperatures are expected to hover
around or just above freezing until the heavier snow falls toward
dawn.
Sensible Weather and Impacts
----------------------------
Current radar does show the two separate storm systems nicely with
light rain over southern KY and mainly light snow overspreading
central IL/IN. We`ll watch through the evening hours as deeper
moisture slowly invades the area, however expect only light
precipitation and no real impacts initially. Southern Indiana could
see light accumulations as early as around sunset. Precipitation will
likely mix at times even across our north as temp profiles fluctuate
under varying degrees of saturation. Really not expecting the main
show to get going until we approach Midnight as system becomes more
organized, column becomes more saturated, and surface temps wet bulb
down toward more wintery precip conducive numbers.
A frontogenetically forced band of snow will then ride SW to NE
across our Warning area, pivoting to a more SSW to NNE orientation
through the night as the right entrance region of an upper level jet
slides overhead. This pivoting should actually enhance the
frontogenesis as well as keep the warm nose near the Ohio River.
Thereafter, the approaching PV anomaly begins to rapidly push the
system east with cold air crashing in in the low to mid levels. The
surface low will strengthen as it slides just to our east, providing
more deep moisture to interact with the cold air.
Since the warm layer aloft is going to drive this event, will
characterize how the overnight progresses by describing its
evolution through several geographic areas.
Southern Indiana (Winter Storm Warning 3-5" of Snow)
----------------------------------------------------
This area is expected to stay below freezing through the thermal
column, so all snow is expected other than a brief mix at onset.
This is expected to yield 3-5 inches by Monday morning, with the
heaviest snow falling between Midnight and 7 AM EST. Impacts to
roads and travel are expected.
Right Along the Ohio River (Winter Weather Advisory 2-3" Snow)
--------------------------------------------------------------
This area is the northern portion of the battleground between the
warm nose aloft. Expect to see mainly snow, however a few brief
periods of wintery mix including some sleet should cut down on
totals a bit. Expect all snow around and after Midnight EST.
Just South of the Ohio River (Winter Weather Advisory 1-3" Snow and
a mix)
-------------------------------------------------------------------
This area will be more see more of the warm air aloft for a longer
time and should cut down on snow totals. Could also see more
bouts of sleet with no impact. The city of Louisville will be right
underneath this battleground, so bust potential is high in this
transition zone. Much will depend on how quick the changeover
occurs. Expect change over between 1 and 4 AM EST.
Bluegrass Region North of I-64 (Winter Weather Advisory 2-4" Snow)
------------------------------------------------------------------
Mostly rain before 4 AM EST. An enhanced area of snow after 4 AM
EST, where deeper moisture mentioned above will be present as two
storm systems phase.
South Central Kentucky (Impact Based Winter Weather Advisory 1" or
less and a brief mix)
-----------------------------------------------------------------
Transition time and the amount of deep moisture left are in question
in this area, as well as rainfall`s effect on ability to accumulate.
Nevertheless, a quick shot of snow around the morning commute, and
the first snow of the year is enough to warrant the advisory.
.LONG TERM (Tuesday through Sunday)...
Issued at 335 PM EST Sun Nov 16 2014
Forecast thoughts in the long term period have not changed much for
this forecast issuance as most of the forecasting focus was on the
Winter Storm Warning/Advisories in the short term period. See the
following excerpts from the previous discussion with a few added
thoughts below.
Deep upper troffing digging from eastern Canada into the United
States, with occasional small reinforcing shots moving through the
flow, will keep us cold for much of the work week, with any
appreciable moderation in temperatures holding off until the weekend
and into next week. Most moisture associated with the upper trof
will stay bottled up to our north, so though it will be cold, it
will also be mostly on the drier side (not necessarily *completely*
dry), with some moisture return possible next weekend.
The models are a mess in the long term, especially Thursday through
Sunday. Models are having difficulty with various shortwaves diving
south across the Plains in an a broad digging upper level trough.
These shortwaves will eventually bring us precip during the latter
half of the week but when, how much, and what type all remain in
question.
The main story Tuesday through Wednesday will be the cold. Tuesday
night we will drop well into the teens. Depending on the location
and depth of any snowpack from tonight`s snowfall, a reading or two
in the single digits may not be out of the question in sheltered
areas from southeast Indiana into the northern Blue Grass. High
temperatures on Tuesday will only be in the lower and middle 20s,
which is about 30 degrees colder than normal!
Wednesday we may be able to moderate up to around 40 in southwest
low level flow between high pressure over Dixie and a cold front
crossing the Great Lakes, but that will be offset by winds gusting
to 25 mph and afternoon wind chills mostly in the 20s.
As mentioned earlier, Thursday through Sunday are tough to figure
out right now. Will lean toward the drier side of the forecast
envelope and keep PoPs small for now. Will bring MaxT`s well up into
the 40s by Saturday with the anticipated pattern change.
&&
.AVIATION (00Z TAF Update)...
Updated at 620 PM EST Sun Nov 16 2014
Winter conditions are on their way for the sites tonight. Cigs will
drop to LIFR or worse for most if not all the overnight period. Rain
ongoing now will transition over to snow, first between 04 and 07Z
at KSDF and later at the other two sites. Vsby will be worse once it
goes over to all snow, but have LIFR conditions persiste through mid
morning, when snow will start to exit off to the east and cigs will
rise slowly. Cannot rule out additional snow showers through the
afternoon and evening, as soundings don`t show much moisture, but
that moisture is in the ice crystal growth zone and there is some
instability as well. Winds will pick up from the west and northwest
through the day tomorrow as the cold air behind this system rushes
in.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WINTER STORM WARNING until Noon EST /11 AM CST/ Monday FOR
KYZ023-032.
WINTER WEATHER ADVISORY from 3 AM EST /2 AM CST/ to Noon EST /11
AM CST/ Monday FOR KYZ027-036-037-039>043-045>049-053>057-
061>065-070>072.
WINTER WEATHER ADVISORY from 11 PM EST /10 PM CST/ this evening
to Noon EST /11 AM CST/ Monday FOR KYZ024>026-028>031-
033>035-038.
IN...WINTER STORM WARNING until Noon EST /11 AM CST/ Monday FOR
INZ076>079-083-084-089>092.
&&
$$
Update.........RJS
Short Term.....BJS
Long Term......AMS
Aviation.......RJS
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
937 PM CST SUN NOV 16 2014
.UPDATE...MADE MINOR ADJUSTMENT TO THE SURFACE WINDS WITH
SLIGHTLY STRONGER WINDS OVERNIGHT WITH THE REINFORCING COLD FRONT
CURRENTLY MOVING THROUGH SOUTHEAST TEXAS AND CENTRAL
LOUISIANA. BLENDED IN LATEST RUC TEMP DATA AND DEW POINT TRENDS
AS WELL AS ACCOUNTING FOR A SLOWER MOVEMENT OF THE COLD FRONT
THROUGH ACADIANA TO ADJUST OVERNIGHT TEMPERATURES. STILL QUITE A
DROP EXPECTED BUT NOW EXPECTING MID 40S FOR SW LA AND UPPER 40S
FOR S CEN LA BY SUNRISE DUE LARGELY TO THE INCREASING WINDS. THESE
CHANGES WILL BE REFLECTED IN ANOTHER ZONE UPDATE OUT SHORLTY.
SWEENEY
&&
.PREV DISCUSSION... /ISSUED 832 PM CST SUN NOV 16 2014/
UPDATE...WENT AHEAD AND CANCELLED THE TOR WATCH A COUPLE OF
HOURS EARLY. WAS IN THE PROCESS OF TRIMMING BACK HOWEVER THE WINDS
AND LIFT BOTH APPEAR TO HAVE WEAKEND AROUND THE FRONTAL BAND. ZONE
UPDATE TO FOLLOW.
SWEENEY
PREV DISCUSSION... /ISSUED 553 PM CST SUN NOV 16 2014/
AVIATION...
STRONG THUNDERSTORMS ARE RUMBLING THRU SOUTH CENTRAL LA AND WILL
BE AN OPERATIONAL ISSUE FOR ARA AND LFT OVER THE NEXT HOUR OR SO.
OTHERWISE LOW CEILINGS WITH PERIODS OF RAINS AND FOG WILL KEEP
VSBY DOWN AT TIMES. CONDITIONS WILL IMPROVE AS A SECOND FRONT
MOVES THROUGH LATE TONIGHT WITH WINDS PICKING UP.
PREV DISCUSSION... /ISSUED 344 PM CST SUN NOV 16 2014/
DISCUSSION...
BUSY WEATHER SITUATION ACROSS THE FORECAST AREA...WITH CONDITIONS
VARYING FROM SPRING TO WINTER WITH SOME 25F DEGREE AIR TEMPERATURE
BETWEEN THE NORTHWEST PORTION OF THE FORECAST AREA WITH THE
SOUTHEAST. OLD FRONTAL BOUNDARY IS BISECTING THE FORECAST AREA
WITH A SURFACE LOW/FRONTAL WAVE LOCATED AS OF 16/21Z BETWEEN
JENNINGS AND LAFAYETTE. WARM SECTOR ON THE EAST SIDE OF THE LOW
EXTENDS FROM EASTERN ST. LANDRY PARISH NEAR THE ATCHAFALAYA BASIN
TO INTO THE GULF WATERS AROUND THE CAMERON/VERMILION PARISH
BORDER. SOME STRONG LOW LEVEL INFLOW WITH A VERY WARM AND MOIST
ENVIRONMENT IS LEADING TO THE DEVELOPMENT OF SHOWERS WITH SOME
EMBEDDED STRONG THUNDERSTORMS IN THE WARM SECTOR. THERE IS A
CHANCE OF SOME ROTATING CELLS BECOMING SURFACE BASED IN THE WARM
SECTOR...AND THEREFORE...SPC HAS ISSUED A TORNADO WATCH FOR SOUTH
CENTRAL LOUISIANA THROUGH 10 PM...ALTHOUGH THE THREAT SHOULD
DIMINISH FOR PORTIONS OF THE AREA BEFORE THEN...AS THE LOW
CONTINUES TO MOVE TO THE NORTHEAST AND LOSS OF DAYTIME HEATING
DECREASES THE LOW LEVEL INSTABILITY.
ANOTHER STRONG COLD FRONT WITH ARCTIC ORIGINS IS CURRENTLY MOVING
SOUTHEAST ACROSS NORTHEAST TEXAS AND NORTHWEST LOUISIANA. THIS
SYSTEM WILL MOVE INTO THE FORECAST AREA THIS EVENING AND INTO THE
COASTAL WATERS DURING THE OVERNIGHT. SHOWERS WILL DECREASE BEHIND
THIS FRONT AS MUCH DRIER AIR BEGINS TO MOVE IN...ALONG WITH
BLUSTERY CONDITIONS.
COLD AIR ADVECTION WILL CONTINUE ON MONDAY...AS THE STRONG HIGH
PRESSURE SYSTEM BUILDS DOWN FROM THE NORTH. CLEAR SKIES ARE
EXPECTED ON MONDAY NIGHT INTO TUESDAY MORNING...WITH A DECREASE IN
WINDS EXPECTED. THEREFORE...A VERY COLD NIGHT IS EXPECTED WITH A
FREEZE FOR A MAJORITY OF THE FORECAST AREA...AND HARD FREEZE
CONDITIONS GETTING DOWN CLOSE TO I-10.
CONDITIONS WILL BEGIN TO MODERATE BY MID-WEEK AS THE HIGH MOVES
OFF TO THE EAST...AND RETURN FLOW OFF THE GULF COMMENCES. ENOUGH
MOISTURE BUILD-UP BY THURSDAY INTO THE WEEKEND...TO INCLUDE A
CHANCE FOR SHOWERS AND STORMS AS A SERIES OF UPPER LEVEL
DISTURBANCES MOVE ACROSS.
RUA
MARINE...
A SURFACE LOW/FRONTAL WAVE WILL MOVE ACROSS SOUTH CENTRAL
LOUISIANA THIS EVENING...THEN SOUTHEAST LOUISIANA TONIGHT.
MODERATE SOUTHERLY WINDS AND INSTABILITY WILL BRING ABOUT SHOWERS
AND STORMS...ESPECIALLY EAST OF CAMERON DURING THE EVENING HOURS.
SOME OF THESE STORMS WILL PRODUCE FREQUENT LIGHTNING...STRONG
WINDS...AND EVEN AN ISOLATED WATER SPOUT CAN NOT BE RULED OUT.
A STRONG COLD FRONT...WILL THEN MOVE ACROSS THE COASTAL WATERS
LATER TONIGHT...REACHING THE WESTERN PORTIONS OF THE COASTAL
WATERS DURING THE LATE EVENING HOURS...AND THEN ACROSS THE
REMAINDER OF THE COASTAL WATERS AFTER MIDNIGHT. AIR FROM THE POLAR
REGION WILL BE BEHIND THIS FRONT. THE DEVELOPING PRESSURE GRADIENT
FROM THE STRONG HIGH PRESSURE SYSTEM...AND STRONG COLD AIR
ADVECTION...WILL PROVIDE TURBULENT AIR MIXING...ALLOWING SOME
STRONG WIND GUSTS TO REACH THE SURFACE...ESPECIALLY OVER THE OUTER
WATERS. THEREFORE...SMALL CRAFT ADVISORY CONDITIONS WILL OVERTAKE
THE COASTAL WATERS TONIGHT...WITH A GALE WARNING FOR FREQUENT WIND
GUSTS OVER 40 KNOTS...BEYOND 20 NM. THE NORTH WIND WILL ALSO PUSH
WATER OUT OF THE CHANNELS AND BAYS AND AWAY FROM THE COAST.
THEREFORE...A LOW WATER ADVISORY WILL ALSO BE IN EFFECT FOR THE
COASTAL LAKES AND BAYS FROM ROUGHLY MIDNIGHT TONIGHT THROUGH NOON MONDAY.
THE STRONG NORTHERLY WINDS WILL BEGIN TO DECREASE BY TUESDAY AS
THE COLD AIR ADVECTION BEGINS TO WANE AND THE HIGH PRESSURE SYSTEM
SETTLES OVER THE REGION.
RUA
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 44 50 27 49 32 / 80 10 0 0 0
KBPT 41 51 29 50 37 / 70 10 0 0 0
KAEX 38 47 24 46 29 / 80 10 0 0 0
KLFT 48 49 27 47 31 / 90 10 0 0 0
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...SMALL CRAFT ADVISORY FROM NOON MONDAY TO NOON CST TUESDAY FOR
THE FOLLOWING ZONES: WATERS FROM INTRACOASTAL CITY TO
CAMERON LA FROM 20 TO 60 NM...WATERS FROM CAMERON LA TO
HIGH ISLAND TX FROM 20 TO 60 NM...WATERS FROM LOWER
ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA FROM 20 TO 60 NM.
GALE WARNING UNTIL NOON CST MONDAY FOR THE FOLLOWING ZONES:
WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA
FROM 20 TO 60 NM.
GALE WARNING UNTIL NOON CST MONDAY FOR THE FOLLOWING ZONES:
WATERS FROM INTRACOASTAL CITY TO CAMERON LA FROM 20 TO 60
NM...WATERS FROM CAMERON LA TO HIGH ISLAND TX FROM 20 TO 60
NM.
LOW WATER ADVISORY UNTIL NOON CST MONDAY FOR THE FOLLOWING
ZONES: CALCASIEU LAKE...SABINE LAKE...VERMILION BAY.
SMALL CRAFT ADVISORY UNTIL NOON CST MONDAY FOR THE FOLLOWING
ZONES: CALCASIEU LAKE...SABINE LAKE...VERMILION BAY.
SMALL CRAFT ADVISORY UNTIL NOON CST TUESDAY FOR THE FOLLOWING
ZONES: COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO
INTRACOASTAL CITY LA OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL NOON CST TUESDAY FOR THE FOLLOWING
ZONES: COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT
20 NM...COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA
OUT 20 NM.
&&
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSLAKECHARLES
WWW.TWITTER.COM/NWSLAKECHARLES
WWW.YOUTUBE.COM/NWSLAKECHARLES
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
259 PM EST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 416 AM EST SAT NOV 15 2014
A QUIET START TO THE SHORT TERM FORECAST THIS MORNING...AS THE AREA
IS ON THE NORTHEAST EDGE OF A HIGH CENTERED FROM THE MID/UPPER
MISSISSIPPI VALLEY TO THE OHIO RIVER VALLEY. THIS HAS LED TO A
CLEAR AND COLD NIGHT ACROSS AT LEAST HALF OF THE CWA. WHERE WINDS
HAVE DECOUPLED (GENERALLY ACROSS THE INTERIOR WEST AND NEAR THE
WISCONSIN BORDER)...TEMPERATURES HAVE FALLEN INTO THE SINGLE
DIGITS BELOW ZERO. MEANWHILE...OVER THE CENTRAL AND EAST WHERE THE
WINDS HAVE BEEN STAYING UP...TEMPERATURES HAVE BEEN IN THE UPPER
SINGLE DIGITS ABOVE ZERO TO MID TEENS.
OVER LAKE SUPERIOR AND THE KEWEENAW...COLD AIR CONTINUING TO FLOW
OVER THE RELATIVELY WARM WATERS OF LAKE SUPERIOR WAS PRODUCING
MAINLY LAKE EFFECT CLOUDS THIS PAST EVENING AND INTO THE EARLY
OVERNIGHT HOURS. BUT STARTED SEEING WEAK LAKE EFFECT BANDS
OVER EASTERN LAKE SUPERIOR ON THE CANADIAN RADAR AT MONTREAL RIVER
SHORTLY AFTER MIDNIGHT. INVERSION IS RIGHT AT 875-850MB ON 00Z
KGRB/KINL SOUNDINGS AND THE LIMITED MOISTURE ON THE NORTH EDGE OF
THE HIGH HAVE BEEN THE MAIN LIMITING FACTORS TO LAKE EFFECT SNOW
EARLY THIS MORNING. KMQT VWP HAS BEEN SHOWING THE WINDS A LITTLE
MORE OUT OF THE WEST-NORTHWEST AND CONTRIBUTING TO THE LAKE EFFECT
CLOUDS NOSING SOUTHEAST INTO BARAGA...SOUTHERN HOUGHTON...AND EVEN
FAR NORTHERN IRON COUNTY EARLY THIS MORNING. BUT AS WE HEAD INTO
THE MORNING HOURS...MODELS SHOWING THE WINDS GOING BACK TO A MORE
WESTERLY AND POTENTIALLY WEST-SOUTHWESTERLY DIRECTION AND CONFINING
THE LAKE EFFECT CLOUDS AND SNOW POTENTIAL TO THE KEWEENAW AND OFF
THE SHORELINE FROM GRAND MARAIS EASTWARD. THIS WILL ALSO BE AIDED
BY THE LAND BREEZE THAT HAS DEVELOPED ALONG THE EASTERN U.P.
SHORELINE AND WILL AID IN KEEPING THE BANDS OFFSHORE THERE. THE
COVERAGE OF THE SHOWERS IS A LITTLE BIT OF A CONCERN DUE TO THE
LIMITED MOISTURE...BUT WOULD EXPECT SOME UPTICK IN THE SNOW SHOWERS
AS 875MB TEMPERATURES FALL FROM -11C ON THE RAP ANALYSIS TO -13/-14C
BY THIS AFTERNOON. THUS...WILL CONTINUE TO SHOW POPS RAMPING UP TO
HIGH CHANCES OVER THE KEWEENAW. WITH MUCH OF THE LAKE EFFECT CLOUD
BELOW THE DGZ...WILL KEEP SNOW RATIOS ON THE LOW END FOR LAKE EFFECT
AND ONLY HAVE ACCUMULATIONS AT A DUSTING TO AN INCH IN THAT AREA.
OVER THE REST OF THE AREA...EXPECT A SUNNY START TO THE DAY WHICH
WILL ALLOW TEMPERATURES TO RISE TO THE LOW-MID 20S THIS AFTERNOON.
EXPECT MORE OF A FILTERED SUNSHINE IN THE AFTERNOON AS HIGH CLOUDS
MOVE IN AHEAD OF THE WAVE BRUSHING THE AREA LATE TONIGHT.
HEADING INTO TONIGHT...FOCUS TURNS TO THE SHORTWAVE CURRENTLY
MOVING THROUGH WYOMING. THIS WAVE WILL QUICKLY SHIFT EAST THROUGH
NEBRASKA AND SOUTH DAKOTA TODAY AND THEN LIFT NORTHEAST ACROSS
NORTHERN LAKE MICHIGAN LATE TONIGHT AND SUNDAY MORNING. EXPECT THE
HIGH CLOUDS TO THICKEN THIS EVENING AND MID CLOUDS TO MOVE IN
DURING THE LATE EVENING AND OVERNIGHT. ANOTHER SHORTWAVE (CURRENTLY
IN COLORADO) WILL LIFT NORTHEAST OUT AHEAD OF THE MAIN WAVE AND
COULD PRODUCE A FEW SHOWERS AROUND MIDNIGHT. THE BETTER/MAIN
FORCING (GENERALLY ABOVE 700MB) COMES FROM THE SECOND SHORTWAVE AND
LOOKS TO STAY SOUTHEAST OF THE AREA...BUT DO EXPECT MENOMINEE COUNTY
AND AREAS ALONG THE LAKE MICHIGAN SHORELINE TO SEE THE BEST
OPPORTUNITY FOR ACCUMULATING SNOW. CURRENT FORECAST HAS SNOWFALL
AMOUNTS UP TO AN INCH OVER SOUTHERN MENOMINEE COUNTY AND TAPERING
OFF TO A HALF INCH OR LESS SOUTH OF A LINE FROM IRON MOUNTAIN TO
MANISTIQUE. SINCE THE NORTHERN EDGE OF THE FORCING WILL BE JUST
BRUSHING THE AREA...DO EXPECT A SHARP CUTOFF TO THE PRECIPITATION TO
THE NORTHWEST AND KEEP THE SNOW CHANCES TO THE SOUTHEAST OF A LINE
FROM MARQUETTE TO WATERSMEET. AS FOR THE LAKE EFFECT OVER THE
KEWEENAW...THIS WAVE WILL BACK THE LOW LEVEL WINDS FARTHER TO THE
SOUTHWEST AND FOCUS ANY LINGERING LAKE EFFECT TO THE FAR NORTHERN
PORTIONS OF THE KEWEENAW PENINSULA. ACCUMULATIONS WILL REMAIN LIGHT
AND BELOW 2 INCHES.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 258 PM EST SAT NOV 15 2014
UPPER LEVEL PATTERN TO BEGIN THE LONG TERM ON SUNDAY NIGHT SHOWS
AMPLIFIED PATTERN WITH RIDGE OVER WESTERN CONUS AND INTO WESTERN
CANADA AND DEEP TROUGHING DOWNSTREAM OVER CNTRL CONUS. MORE RIDGING
WILL BE IN PLACE DOWNSTREAM OVER THE EASTERN CONUS. TROUGH DEEPENS
OVER THE GREAT LAKES EARLY IN THE WEEK...THEN RELAXES SLIGHTLY
BEFORE MORE TROUGHING BRINGS ANOTHER SHOT OF ARCTIC AIR OVER THE
GREAT LAKES TOWARD END OF THE WEEK. JET ENERGY BECOMES MORE FOCUSED
ON LEADING EDGE OF TROUGHING BY NEXT WEEKEND ALLOWING THE TROUGH TO
MOVE EAST AND ALLOWING RIDGING WITH MODERATING TEMPERATURES TO
RETURN TO THE GREAT LAKES BEGINNING NEXT WEEKEND.
UNTIL THEN THE MAIN THEME OF THIS WEEK WILL BE COLD WITH LAKE EFFECT
SNOW SHOWERS. INITIALLY AN UPPER LOW AND ASSOCIATED SFC LOW WORKS
ACROSS LK SUPERIOR REGION ON MONDAY. TREND TOWARD A SLOWER FROPA
WITH THE SYSTEM. FRONT SHOULD SWEEP ACROSS WETSERN CWA AROUND
DAYBREAK ON MONDAY AND NOT REACH EASTERN CWA UNTIL MONDAY AFTN.
BLYR WINDS SHIFT NW BEHIND THE FRONT AND THERE IS SUFFICIENT DEEPER
MOISTURE TO H7-H6 FOR LAKE ENHANCED SNOW AS H85 TEMPS ARE AROUND
-15C. LARGE SCALE FORCING WILL MAINLY BE TO THE EAST OF MUCH OF UPR
MICHIGAN BY MONDAY AFTN...BUT EVEN THEN SOUNDINGS SHOW UNSTABLE
PROFILE SFC-H7 WITH SUFFICIENT MOISTURE AND STRONG ENOUGH WINDS TO
LEAD TO SNOW SHOWERS OVER MUCH OF UPR MICHIGAN. BY FAR THOUGH THE
BEST CHANCE OF SNOW SHOWERS WILL BE TIED TO LAKE EFFECT FOR NW FLOW
AREAS OVER WESTERN UPR MICHIGAN AND EVENTUALLY IN THE SNOW BELTS
OVER EAST HALF OF UPR MICHIGAN AS OVER-WATER INSTABILITY IS VERY
FAVORABLE WITH DELTA T/S OVER 20C AND LAKE EQ LEVELS OVER 15KFT.
CYCLONIC FLOW SFC-H7 WILL ONLY ENHANCE THE CONVERGENCE AND SNOW
SHOWER INTENSITY. EXPECT SOME OF THE HEAVIEST LAKE EFFECT SNOW TO
OCCUR MONDAY AFTN/MONDAY NIGHT AND INTO TUESDAY WHEN THE DEEPER
MOISTURE TO H7 IS PRESENT AND CYCLONIC FLOW IS STRONGEST. SFC-925MB
WINDS INDICATE AREAS FAVORED BY NNW FLOW WILL SEE THE MOST
CONCENTRATED LAKE EFFECT...HOWEVER H85-H7 WINDS ARE MORE FM THE
N-NNW...SO THIS COULD BRING PERIODS OF LAKE EFFECT INTO AREAS
FAVORED BY THAT FLOW REGIME AS WELL. OVERALL...MODERATE TO HEAVY
LAKE EFFECT SNOW IS EXPECTED ALONG MUCH OF LK SUPERIOR LATER MONDAY
INTO TUESDAY MORNING. MOISTURE OFF THE STILL OPEN WATERS OF LK
NIPEGON COULD ALSO SERVE AS ENHANCEMENT FACTOR THE LAKE EFFECT.
THERE ARE STILL TIMING AND LOCATION UNCERTAINTIES SO WILL NOT ISSUE
ANY LAKE EFFECT SNOW WATCHES YET BUT WILL CONTINUE TO MENTION THE
POTENTIAL FOR HEAVY LAKE EFFECT IN HAZARDOUS WEATHER OUTLOOK AND THE
EHWO GRAPHICS.
SHORTWAVE TROUGH MOVES EAST ON TUESDAY TAKING THE DEEP MOISTURE
STEADILY OUT OF THE UPPER GREAT LAKES BY AFTERNOON. ALL THE WHILE
EXPECT NW WINDS IN LAKE EFFECT MOIST LAYER TO BECOME MORE WESTERLY
BY LATE IN THE DAY...PUSHING THE LAKE EFFECT SNOW SHOWERS ACROSS
THE KEWEENAW AND ALONG LK SUPERIOR EAST OF MUNISING. AS ALLUDED TO
BEFORE...LARGE SCALE TROUGH IS RE-INFORCED LATER IN THE WEEK AS A
COUPLE OF SHORTWAVES DIVE ACROSS THE UPPER GREAT LAKES REGION.
POSSIBLE THAT COULD SEE A SWATH OF WIDESPREAD LIGHT SNOW AS THESE
WORK ACROSS LATE TUESDAY NIGHT INTO WEDNESDAY...THOUGH MOISTURE IS
REALLY LACKING AS H7 MIXING RATIOS ARE BARELY ABOVE 1G/KG SUGGESTING
JUST A DUSTING OF SNOW WOULD OCCUR AWAY FM THE GREAT LAKES. APPEARS
THAT THERE MAY BE BRIEF OPPORTUNITY FOR LAKE ENHANCED SNOW OFF LK
MICHIGAN AS WINDS BACK FM WSW TO SSW AS WITH FORCING PRESENT AND AS
H85 TEMPS ARE AROUND -10C. FOR MOST PART THOUGH...THINK BETTER LAKE
ENHANCEMENT STAYS JUST EAST OF THE CWA. AS SECOND SHORTWAVE MOVES
THROUGH LATER ON WEDNESDAY ALONG WITH SUB 1000MB SFC LOW AND COLD
FRONT...LIKELY WILL SEE ANOTHER ROUND OF MODERATE TO HEAVY LAKE
ENHANCED SNOW KICK UP AGAIN WITH H85 TEMPS AROUND -14C AND MORE
DEEPER MOISTURE THROUGH H7. BASED ON UNIDIRECTIONAL FLOW SFC-H7 THE
MOST SNOW WOULD OCCUR ESPECIALLY FOR AREAS FAVORED BY WNW WINDS.
LAKE EFFECT WILL BE ON THE MOVE AGAIN ON THURSDAY...HEADING TOWARD
AREAS FAVORED BY NORTHWEST WINDS. MID SHIFT HIGHLIGHTED THIS TIME
FRAME FOR HEAVY LAKE EFFECT SNOW POTENTIAL IN THE HWO AND EHWO
GRAPHICS. WILL FOLLOW SUIT WITH THIS FORECAST.
INSTENSITY FOR LAKE EFFECT BEGINS TO DIMINISH LATER THURSDAY AND
CERTAINLY BY FRIDAY AS SOUNDINGS INDICATE INVERSIONS LOWERING TO
AROUND 5KFT INSTEAD OF THE MORE ROBUST 10KFT+ THEY ARE FOR MOST OF
THE WEEK. MORE ANTICYCLONIC LOW-LEVEL FLOW WITH APPROACHING RIDGE
WILL ALSO KNOCK DOWN INTENSITY OF SNOW SHOWERS AND LEAD TO LESS
COVERAGE OF THE LAKE EFFECT.
WINDS BACK WSW-SW FRIDAY NIGHT INTO SATURDAY AS HIGH PRESSURE RIDGE
ARRIVES. BETWEEN BACKING WINDS AND WARMING TEMPS IN LOW-LEVELS...
LAKE EFFECT SNOW SHOWERS SHOULD END BY SATURDAY. 12Z GFS SHOWS
DECENT WARM AND MOIST ADVECTION SNOW ON BACK SIDE OF RIDGE. NO
CONSISTENCY WITH PREVIOUS RUNS THOUGH NOR THE ECMWF WHICH HAS THE
AREA MAINLY DRY. 12Z GFS REPRESENTS JUST A HIGHER-END SNOW ENSEMBLE
MEMBER AT THIS POINT. GIVEN THE DEPTH OF THE COLD AIR DOME THAT WILL
BE RETREATING BY THAT TIME...COULD SEE SOME ISENTROPIC LIFT TYPE
SNOW...BUT JUST NOT SURE IT WILL BE TO THE EXTENT THE GFS SHOWS.
WILL GO WITH CONSENSUS OF MODELS ATTM AND WE CAN FINE TUNE FOR LATER
FORECASTS. WARMING TREND DOES APPEAR TO BEGIN ON SATURDAY WHICH MAY
RESULT IN TEMPS JUST BEYOND THE EXTENDED REACHING BACK ABOVE NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1245 PM EST SAT NOV 15 2014
GUSTY WESTERLY WINDS OFF LAKE SUPERIOR WILL CONTINUE TO LEAD TO LAKE
EFFECT CLOUDS /HIGH END MVFR/LOW END VFR/ WITH OFF AND ON SNOW
SHOWERS AND BLOWING SNOW REDUCING VIS TO AROUND 6SM AT TIMES THROUGH
EARLY EVENING.
FOR KIWD/KSAW...EXPECT VFR CONDITIONS DUE TO UNFAVORABLE WIND
DIRECTIONS FOR LAKE EFFECT. AN APPROACHING UPPER LEVEL DISTURBANCE
WILL LEAD TO INCREASING HIGH/MID CLOUDS THIS AFTERNOON-TONIGHT. KSAW
WILL BE THE CLOSEST FOR SOME SNOW SHOWERS...AND HAVE ADDED THE
POTENTIAL FROM 11-16Z AS CEILINGS FALL TO MVFR. EXPECT SW WINDS TO
INCREASE AT ALL 3 SITES SUNDAY MORNING WITH GUSTS NEARING 20KTS
PRIOR TO 18Z.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EST SAT NOV 15 2014
UNDER A SHARP PRES GRADIENT BETWEEN HI PRES IN THE OH RIVER VALLEY
AND LO PRES OVER HUDSON BAY...PLAN ON W WINDS UP TO 20-30KTS INTO
SUN. THE WINDS WL THEN BACK TOWARD THE SW AND DIMINISH TO UP TO
25KTS IN ADVANCE OF ANOTHER STRONG DISTURBANCE MOVING THRU SCENTRAL
CANADA AND INTO NORTHERN LAKE SUPERIOR ON MON MORNING. FOLLOWING THE
PASSAGE OF THIS LO TO THE E...THE PRES GRADIENT WILL TIGHTEN AND THE
INSTABILITY WILL INCREASE AS ANOTHER SURGE OF COLD AIR FLOWS OVER
THE RELATIVELY WARM LAKE WATERS. THE RESULT WILL BE A PERIOD OF NW
GALES ON MON INTO TUE. SINCE THIS AIRMASS WILL BE SUFFICIENTLY
COLD...THERE WILL LIKELY BE SOME FREEZING SPRAY IN SOME AREAS. THE
BEST CHANCE FOR THE GALES WILL BE OVER CENTRAL LAKE SUPERIOR. AS THE
LO PRES MOVES AWAY ON TUE AND HI PRES SHIFTS E...EXPECT THE WINDS TO
BACK TO THE W AND DIMINISH TO 25 TO 30KTS. THE PASSAGE OF ANOTHER
STRONG DISTURBANCE ON WED MAY LEAD TO ANOTHER NW GALE EVENT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...JLA
AVIATION...KF
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1246 PM EST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 416 AM EST SAT NOV 15 2014
A QUIET START TO THE SHORT TERM FORECAST THIS MORNING...AS THE AREA
IS ON THE NORTHEAST EDGE OF A HIGH CENTERED FROM THE MID/UPPER
MISSISSIPPI VALLEY TO THE OHIO RIVER VALLEY. THIS HAS LED TO A
CLEAR AND COLD NIGHT ACROSS AT LEAST HALF OF THE CWA. WHERE WINDS
HAVE DECOUPLED (GENERALLY ACROSS THE INTERIOR WEST AND NEAR THE
WISCONSIN BORDER)...TEMPERATURES HAVE FALLEN INTO THE SINGLE
DIGITS BELOW ZERO. MEANWHILE...OVER THE CENTRAL AND EAST WHERE THE
WINDS HAVE BEEN STAYING UP...TEMPERATURES HAVE BEEN IN THE UPPER
SINGLE DIGITS ABOVE ZERO TO MID TEENS.
OVER LAKE SUPERIOR AND THE KEWEENAW...COLD AIR CONTINUING TO FLOW
OVER THE RELATIVELY WARM WATERS OF LAKE SUPERIOR WAS PRODUCING
MAINLY LAKE EFFECT CLOUDS THIS PAST EVENING AND INTO THE EARLY
OVERNIGHT HOURS. BUT STARTED SEEING WEAK LAKE EFFECT BANDS
OVER EASTERN LAKE SUPERIOR ON THE CANADIAN RADAR AT MONTREAL RIVER
SHORTLY AFTER MIDNIGHT. INVERSION IS RIGHT AT 875-850MB ON 00Z
KGRB/KINL SOUNDINGS AND THE LIMITED MOISTURE ON THE NORTH EDGE OF
THE HIGH HAVE BEEN THE MAIN LIMITING FACTORS TO LAKE EFFECT SNOW
EARLY THIS MORNING. KMQT VWP HAS BEEN SHOWING THE WINDS A LITTLE
MORE OUT OF THE WEST-NORTHWEST AND CONTRIBUTING TO THE LAKE EFFECT
CLOUDS NOSING SOUTHEAST INTO BARAGA...SOUTHERN HOUGHTON...AND EVEN
FAR NORTHERN IRON COUNTY EARLY THIS MORNING. BUT AS WE HEAD INTO
THE MORNING HOURS...MODELS SHOWING THE WINDS GOING BACK TO A MORE
WESTERLY AND POTENTIALLY WEST-SOUTHWESTERLY DIRECTION AND CONFINING
THE LAKE EFFECT CLOUDS AND SNOW POTENTIAL TO THE KEWEENAW AND OFF
THE SHORELINE FROM GRAND MARAIS EASTWARD. THIS WILL ALSO BE AIDED
BY THE LAND BREEZE THAT HAS DEVELOPED ALONG THE EASTERN U.P.
SHORELINE AND WILL AID IN KEEPING THE BANDS OFFSHORE THERE. THE
COVERAGE OF THE SHOWERS IS A LITTLE BIT OF A CONCERN DUE TO THE
LIMITED MOISTURE...BUT WOULD EXPECT SOME UPTICK IN THE SNOW SHOWERS
AS 875MB TEMPERATURES FALL FROM -11C ON THE RAP ANALYSIS TO -13/-14C
BY THIS AFTERNOON. THUS...WILL CONTINUE TO SHOW POPS RAMPING UP TO
HIGH CHANCES OVER THE KEWEENAW. WITH MUCH OF THE LAKE EFFECT CLOUD
BELOW THE DGZ...WILL KEEP SNOW RATIOS ON THE LOW END FOR LAKE EFFECT
AND ONLY HAVE ACCUMULATIONS AT A DUSTING TO AN INCH IN THAT AREA.
OVER THE REST OF THE AREA...EXPECT A SUNNY START TO THE DAY WHICH
WILL ALLOW TEMPERATURES TO RISE TO THE LOW-MID 20S THIS AFTERNOON.
EXPECT MORE OF A FILTERED SUNSHINE IN THE AFTERNOON AS HIGH CLOUDS
MOVE IN AHEAD OF THE WAVE BRUSHING THE AREA LATE TONIGHT.
HEADING INTO TONIGHT...FOCUS TURNS TO THE SHORTWAVE CURRENTLY
MOVING THROUGH WYOMING. THIS WAVE WILL QUICKLY SHIFT EAST THROUGH
NEBRASKA AND SOUTH DAKOTA TODAY AND THEN LIFT NORTHEAST ACROSS
NORTHERN LAKE MICHIGAN LATE TONIGHT AND SUNDAY MORNING. EXPECT THE
HIGH CLOUDS TO THICKEN THIS EVENING AND MID CLOUDS TO MOVE IN
DURING THE LATE EVENING AND OVERNIGHT. ANOTHER SHORTWAVE (CURRENTLY
IN COLORADO) WILL LIFT NORTHEAST OUT AHEAD OF THE MAIN WAVE AND
COULD PRODUCE A FEW SHOWERS AROUND MIDNIGHT. THE BETTER/MAIN
FORCING (GENERALLY ABOVE 700MB) COMES FROM THE SECOND SHORTWAVE AND
LOOKS TO STAY SOUTHEAST OF THE AREA...BUT DO EXPECT MENOMINEE COUNTY
AND AREAS ALONG THE LAKE MICHIGAN SHORELINE TO SEE THE BEST
OPPORTUNITY FOR ACCUMULATING SNOW. CURRENT FORECAST HAS SNOWFALL
AMOUNTS UP TO AN INCH OVER SOUTHERN MENOMINEE COUNTY AND TAPERING
OFF TO A HALF INCH OR LESS SOUTH OF A LINE FROM IRON MOUNTAIN TO
MANISTIQUE. SINCE THE NORTHERN EDGE OF THE FORCING WILL BE JUST
BRUSHING THE AREA...DO EXPECT A SHARP CUTOFF TO THE PRECIPITATION TO
THE NORTHWEST AND KEEP THE SNOW CHANCES TO THE SOUTHEAST OF A LINE
FROM MARQUETTE TO WATERSMEET. AS FOR THE LAKE EFFECT OVER THE
KEWEENAW...THIS WAVE WILL BACK THE LOW LEVEL WINDS FARTHER TO THE
SOUTHWEST AND FOCUS ANY LINGERING LAKE EFFECT TO THE FAR NORTHERN
PORTIONS OF THE KEWEENAW PENINSULA. ACCUMULATIONS WILL REMAIN LIGHT
AND BELOW 2 INCHES.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 409 AM EST SAT NOV 15 2014
A HI AMPLITUDE PATTERN FEATURING A TROF OVER CENTRAL AND ERN
NAMERICA DOWNSTREAM OF A RDG ALONG THE W COAST WL DOMINATE THE WX
PATTERN THIS COMING WEEK...LEADING TO PERSISTENT BLO TO WELL BLO
NORMAL TEMPS THRU THE WEEK. THE MOST SGNFT WX CONCERN WL BE THE
IMPACT OF A POTENT SHRTWV THAT IS FCST TO DIG SEWD THRU THE UPR LKS
EARLY IN THE WEEK AND AMPLIFY THE TROF. THIS DISTURBANCE WL ALMOST
CERTAINLY BRING ANOTHER ROUND OF MODERATE TO HEAVY LES AND SOME BLSN
MAINLY TO THE NW WIND SN BELTS NEAR LK SUP ON MON INTO TUE. YET
ANOTHER DISTURBANCE DIGGING THRU THE UPR TROF MAY BRING MORE SGNFT
LES ON WED INTO THU.
SUN...ONGOING LIGHT SN OVER THE SE CWA WL END BY EARLY IN THE AFTN
AS SHRTWV OVER ERN WI AT 12Z AND ACCOMPANYING DYNAMIC FORCING/
DEEPER MSTR EXIT TO THE E THRU LOWER MI AND INTO FAR SE ONTARIO IN
THE AFTN. AXIS OF DRIER AIR/DEEP LYR QVECTOR DVGC BTWN THIS
DEPARTING SHRTWV AND ANOTHER MORE POTENT SHRTWV DIGGING SE THRU
SCENTRAL CANADA WL THEN BRING A PERIOD OF DRY WX TO THE CWA.
ALTHOUGH H85 TEMPS ARE FCST TO BE AS LO AS -12 TO -13C...THE FCST
230 DEGREE LLVL FLOW IN ADVANCE OF THE APRCHG SHRTWV WL HOLD ANY LES
MAINLY TO THE NW OF THE KEWEENAW PENINSULA AND E OF LUCE/SCHOOLCRAFT
COUNTIES. ALTHOUGH DPVA/DEEP LYR QVECTOR CNVGC IN ADVANCE OF THE
INCOMING SHRTWV ARE FCST TO INVADE THE WRN CWA LATER IN THE DAY...
THE ABSENCE OF ANY SGNFT LLVL MSTR INFLOW WL MAINTAIN DRY WX THRU
00Z MON UNDER INCRSG HI/MID CLDS.
SUN NIGHT...INCOMING SHRTWV/SFC LO ARE FCST TO DRIFT OVER NRN LK SUP
BY 12Z MON AND CAUSE 12HR H5 HGT FALLS UP TO 120M ACROSS THE UPR
LKS. AXIS OF DPVA/DEEP LYR QVECTOR CNVGC WITHIN THE COMMA TAIL OF
THIS FEATURE ARE FCST TO SWING ACROSS UPR MI. HOWEVER...POTENTIAL
FOR WIDESPREAD SN IN ADVANCE OF THE SHRTWV WL BE LIMITED BY THE
ABSENCE OF LLVL MOISTENING/PWAT UNDER 0.25 INCH/H7 SPECIFIC HUMIDITY
NO MORE THAN ABOUT 1 G/KG. STILL LOOKS LIKE THE LLVL FLOW WL NOT
BACK SUFFICIENTLY TO ALLOW ANY LK ENHANCED OFF LK MI TO IMPACT LUCE
OR SCHOOLCRAFT COUNTIES. THE BEST CHC FOR MORE WIDESPREAD/HEAVIER
SNOW WL BE OVER THE W MAINLY LATE FOLLOWING COLD FROPA AND WIND
SHIFT TO AN UPSLOPE NW DIRECTION. ARRIVAL OF H85 TEMPS AROUND -15C
WITH SHARP CYC FLOW/LINGERING DEEP MSTR UNDER THE FALLING HGTS WILL
WARRANT KEEPING LIKELY TO CATEGORICAL POPS OVER THE W. WL GO NO HIER
THAN CHC POPS ELSEWHERE...WITH THE LOWEST SCHC POPS OVER THE
SCENTRAL.
MON/MON NGT...AS THE UPR TROF DEEPENS INTO THE GREAT LKS AND A
CLOSED H5 LO FORMS...UPR MI IS FCST TO BE UNDER SHARP...CYC W
VEERING NW FLOW ON MON AND NNW-NW FLOW ON MON NGT. FCST SDNGS SHOW
DEEP MOISTURE/INSTABILITY AS H5 TEMPS DIP TOWARD -40C. GIVEN H85
TEMPS FALLING TO -16C TO -18C AND THE DEEP INSTABILITY/MOISTURE WITH
THE CYC LLVL FLOW...CATEGORICAL POPS ARE WARRANTED IN THE FAVORED SN
BELTS. GUSTY WINDS UNDER THE SHARP PRES GRADIENT/DESTABILIZATION WL
CAUSE BLSN IN ADDITIONAL TO THE HEAVIER LES. FAVORABLE OMEGA PROFILE
WITHIN THE DGZ SITUATED BTWN ABOUT 1-5K FT AGL WL ALSO ENHANCE
SN/WATER RATIOS DESPITE THE IMPACT OF THE STRONG WINDS TO FRAGMENT
THE SN FLAKES. RIGHT NOW... THE FAR W IN ONTONAGON/GOGEBIC COUNTIES
LOOKS TO PICK UP THE HEAVIEST SN ON MON NGT...WITH ADDITIONAL HEAVY
LES IMPACTING AREAS E OF MARQUETTE LATER ON MON THRU MON NGT. LATER
SHIFTS NO DOUBT WL NEED TO HOIST LES HEADLINES. THE STRONG NW WINDS
MAY ALSO CAUSE HI ENOUGH WAVES ON LK SUPERIOR TO BRING SOME MINOR
BEACH EROSION/FLOODING IN AREAS MOST EXPOSED TO THE HIER WINDS/WAVES
BEGINNING ON LATE MON. FOR NOW...WL CONTINUE TO MENTION THE SGFNT
LES POTENTIAL/BLSN AND HI WAVES IN THE HWO PRODUCT AND EHWO GRAPHICS.
TUE/TUE NGT...AS THE CLOSED LO SHIFTS INTO QUEBEC AND 12HR H5 HGT
RISES APRCH 100M ON TUE IN THE LARGER SCALE DNVA AHEAD OF TRAILING
H5 RDG AXIS...MID LVL SUBSIDENCE/DRYING/TREND TOWARD NEUTRAL OR MORE
ACYC LLVL FLOW WL TEND TO WEAKEN THE LES W TO E. STEADILY BACKING
WINDS OVER THE W THRU THE DAY AND MAINLY DURING TUE AFTN OVER THE E
WL TEND TO LIMIT THE RESIDENCE TIME OF THE HEAVIER SN BANDS AND
SHIFT THE LES TO PRIMARILY OVER THE KEWEENAW AND TO THE E OF
MUNISING BY LATE IN THE DAY. DESPITE THIS DIMINISHING TREND...SN
TOTALS ON MON THRU TUE WL LIKELY APRCH OR EXCEED A FOOT IN THE
FAVORED SN BELTS OVER THE W CENTERED IN ONTONAGON COUNTY AND E OF
MUNISING. AS THE FLOW CONTINUES TO BACK TOWARD THE SW ON TUE NGT IN
ADVANCE OF NEXT CLIPPER SHRTWV DIGGING SEWD TOWARD MN...THE MAIN
AREA OF LES SHOULD SHIFT INTO LK SUP. BUT MORE WIDESPREAD SN MAY
ARRIVE LATE AT NGT AT LEAST OVER THE W WITH THE ONSET OF MORE
VIGOROUS DYNAMIC FORCING/HGT FALLS IN THE DPVA AHEAD OF THE NEXT
SHRTWV.
WED THRU FRI...PASSAGE OF POTENT SHRTWV/VIGOROUS DYNAMIC FORCING WL
BRING THE THREAT OF A MORE WIDESPREAD SN AGAIN ON WED DESPITE RATHER
LIMITED ABSOLUTE MSTR /FCST PWAT UNDER 0.25 INCH/. MORE LES WL BE
THE RULE ON THU INTO FRI MAINLY IN THE NW WIND SN BELTS AS ANOTHER
COLD SHOT WITH H85 TEMPS AS LO AS -16 TO -18C POURS INTO THE UPR LKS
BEHIND THE DEPARTING SHRTWV. LONGER RANGE MODELS CONTINUE TO POINT
TOWARD SOME MODERATION IN THE COLD NEXT WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1245 PM EST SAT NOV 15 2014
GUSTY WESTERLY WINDS OFF LAKE SUPERIOR WILL CONTINUE TO LEAD TO LAKE
EFFECT CLOUDS /HIGH END MVFR/LOW END VFR/ WITH OFF AND ON SNOW
SHOWERS AND BLOWING SNOW REDUCING VIS TO AROUND 6SM AT TIMES THROUGH
EARLY EVENING.
FOR KIWD/KSAW...EXPECT VFR CONDITIONS DUE TO UNFAVORABLE WIND
DIRECTIONS FOR LAKE EFFECT. AN APPROACHING UPPER LEVEL DISTURBANCE
WILL LEAD TO INCREASING HIGH/MID CLOUDS THIS AFTERNOON-TONIGHT. KSAW
WILL BE THE CLOSEST FOR SOME SNOW SHOWERS...AND HAVE ADDED THE
POTENTIAL FROM 11-16Z AS CEILINGS FALL TO MVFR. EXPECT SW WINDS TO
INCREASE AT ALL 3 SITES SUNDAY MORNING WITH GUSTS NEARING 20KTS
PRIOR TO 18Z.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EST SAT NOV 15 2014
UNDER A SHARP PRES GRADIENT BETWEEN HI PRES IN THE OH RIVER VALLEY
AND LO PRES OVER HUDSON BAY...PLAN ON W WINDS UP TO 20-30KTS INTO
SUN. THE WINDS WL THEN BACK TOWARD THE SW AND DIMINISH TO UP TO
25KTS IN ADVANCE OF ANOTHER STRONG DISTURBANCE MOVING THRU SCENTRAL
CANADA AND INTO NORTHERN LAKE SUPERIOR ON MON MORNING. FOLLOWING THE
PASSAGE OF THIS LO TO THE E...THE PRES GRADIENT WILL TIGHTEN AND THE
INSTABILITY WILL INCREASE AS ANOTHER SURGE OF COLD AIR FLOWS OVER
THE RELATIVELY WARM LAKE WATERS. THE RESULT WILL BE A PERIOD OF NW
GALES ON MON INTO TUE. SINCE THIS AIRMASS WILL BE SUFFICIENTLY
COLD...THERE WILL LIKELY BE SOME FREEZING SPRAY IN SOME AREAS. THE
BEST CHANCE FOR THE GALES WILL BE OVER CENTRAL LAKE SUPERIOR. AS THE
LO PRES MOVES AWAY ON TUE AND HI PRES SHIFTS E...EXPECT THE WINDS TO
BACK TO THE W AND DIMINISH TO 25 TO 30KTS. THE PASSAGE OF ANOTHER
STRONG DISTURBANCE ON WED MAY LEAD TO ANOTHER NW GALE EVENT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KC
AVIATION...KF
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
635 AM EST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 416 AM EST SAT NOV 15 2014
A QUIET START TO THE SHORT TERM FORECAST THIS MORNING...AS THE AREA
IS ON THE NORTHEAST EDGE OF A HIGH CENTERED FROM THE MID/UPPER
MISSISSIPPI VALLEY TO THE OHIO RIVER VALLEY. THIS HAS LED TO A
CLEAR AND COLD NIGHT ACROSS AT LEAST HALF OF THE CWA. WHERE WINDS
HAVE DECOUPLED (GENERALLY ACROSS THE INTERIOR WEST AND NEAR THE
WISCONSIN BORDER)...TEMPERATURES HAVE FALLEN INTO THE SINGLE
DIGITS BELOW ZERO. MEANWHILE...OVER THE CENTRAL AND EAST WHERE THE
WINDS HAVE BEEN STAYING UP...TEMPERATURES HAVE BEEN IN THE UPPER
SINGLE DIGITS ABOVE ZERO TO MID TEENS.
OVER LAKE SUPERIOR AND THE KEWEENAW...COLD AIR CONTINUING TO FLOW
OVER THE RELATIVELY WARM WATERS OF LAKE SUPERIOR WAS PRODUCING
MAINLY LAKE EFFECT CLOUDS THIS PAST EVENING AND INTO THE EARLY
OVERNIGHT HOURS. BUT STARTED SEEING WEAK LAKE EFFECT BANDS
OVER EASTERN LAKE SUPERIOR ON THE CANADIAN RADAR AT MONTREAL RIVER
SHORTLY AFTER MIDNIGHT. INVERSION IS RIGHT AT 875-850MB ON 00Z
KGRB/KINL SOUNDINGS AND THE LIMITED MOISTURE ON THE NORTH EDGE OF
THE HIGH HAVE BEEN THE MAIN LIMITING FACTORS TO LAKE EFFECT SNOW
EARLY THIS MORNING. KMQT VWP HAS BEEN SHOWING THE WINDS A LITTLE
MORE OUT OF THE WEST-NORTHWEST AND CONTRIBUTING TO THE LAKE EFFECT
CLOUDS NOSING SOUTHEAST INTO BARAGA...SOUTHERN HOUGHTON...AND EVEN
FAR NORTHERN IRON COUNTY EARLY THIS MORNING. BUT AS WE HEAD INTO
THE MORNING HOURS...MODELS SHOWING THE WINDS GOING BACK TO A MORE
WESTERLY AND POTENTIALLY WEST-SOUTHWESTERLY DIRECTION AND CONFINING
THE LAKE EFFECT CLOUDS AND SNOW POTENTIAL TO THE KEWEENAW AND OFF
THE SHORELINE FROM GRAND MARAIS EASTWARD. THIS WILL ALSO BE AIDED
BY THE LAND BREEZE THAT HAS DEVELOPED ALONG THE EASTERN U.P.
SHORELINE AND WILL AID IN KEEPING THE BANDS OFFSHORE THERE. THE
COVERAGE OF THE SHOWERS IS A LITTLE BIT OF A CONCERN DUE TO THE
LIMITED MOISTURE...BUT WOULD EXPECT SOME UPTICK IN THE SNOW SHOWERS
AS 875MB TEMPERATURES FALL FROM -11C ON THE RAP ANALYSIS TO -13/-14C
BY THIS AFTERNOON. THUS...WILL CONTINUE TO SHOW POPS RAMPING UP TO
HIGH CHANCES OVER THE KEWEENAW. WITH MUCH OF THE LAKE EFFECT CLOUD
BELOW THE DGZ...WILL KEEP SNOW RATIOS ON THE LOW END FOR LAKE EFFECT
AND ONLY HAVE ACCUMULATIONS AT A DUSTING TO AN INCH IN THAT AREA.
OVER THE REST OF THE AREA...EXPECT A SUNNY START TO THE DAY WHICH
WILL ALLOW TEMPERATURES TO RISE TO THE LOW-MID 20S THIS AFTERNOON.
EXPECT MORE OF A FILTERED SUNSHINE IN THE AFTERNOON AS HIGH CLOUDS
MOVE IN AHEAD OF THE WAVE BRUSHING THE AREA LATE TONIGHT.
HEADING INTO TONIGHT...FOCUS TURNS TO THE SHORTWAVE CURRENTLY
MOVING THROUGH WYOMING. THIS WAVE WILL QUICKLY SHIFT EAST THROUGH
NEBRASKA AND SOUTH DAKOTA TODAY AND THEN LIFT NORTHEAST ACROSS
NORTHERN LAKE MICHIGAN LATE TONIGHT AND SUNDAY MORNING. EXPECT THE
HIGH CLOUDS TO THICKEN THIS EVENING AND MID CLOUDS TO MOVE IN
DURING THE LATE EVENING AND OVERNIGHT. ANOTHER SHORTWAVE (CURRENTLY
IN COLORADO) WILL LIFT NORTHEAST OUT AHEAD OF THE MAIN WAVE AND
COULD PRODUCE A FEW SHOWERS AROUND MIDNIGHT. THE BETTER/MAIN
FORCING (GENERALLY ABOVE 700MB) COMES FROM THE SECOND SHORTWAVE AND
LOOKS TO STAY SOUTHEAST OF THE AREA...BUT DO EXPECT MENOMINEE COUNTY
AND AREAS ALONG THE LAKE MICHIGAN SHORELINE TO SEE THE BEST
OPPORTUNITY FOR ACCUMULATING SNOW. CURRENT FORECAST HAS SNOWFALL
AMOUNTS UP TO AN INCH OVER SOUTHERN MENOMINEE COUNTY AND TAPERING
OFF TO A HALF INCH OR LESS SOUTH OF A LINE FROM IRON MOUNTAIN TO
MANISTIQUE. SINCE THE NORTHERN EDGE OF THE FORCING WILL BE JUST
BRUSHING THE AREA...DO EXPECT A SHARP CUTOFF TO THE PRECIPITATION TO
THE NORTHWEST AND KEEP THE SNOW CHANCES TO THE SOUTHEAST OF A LINE
FROM MARQUETTE TO WATERSMEET. AS FOR THE LAKE EFFECT OVER THE
KEWEENAW...THIS WAVE WILL BACK THE LOW LEVEL WINDS FARTHER TO THE
SOUTHWEST AND FOCUS ANY LINGERING LAKE EFFECT TO THE FAR NORTHERN
PORTIONS OF THE KEWEENAW PENINSULA. ACCUMULATIONS WILL REMAIN LIGHT
AND BELOW 2 INCHES.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 409 AM EST SAT NOV 15 2014
A HI AMPLITUDE PATTERN FEATURING A TROF OVER CENTRAL AND ERN
NAMERICA DOWNSTREAM OF A RDG ALONG THE W COAST WL DOMINATE THE WX
PATTERN THIS COMING WEEK...LEADING TO PERSISTENT BLO TO WELL BLO
NORMAL TEMPS THRU THE WEEK. THE MOST SGNFT WX CONCERN WL BE THE
IMPACT OF A POTENT SHRTWV THAT IS FCST TO DIG SEWD THRU THE UPR LKS
EARLY IN THE WEEK AND AMPLIFY THE TROF. THIS DISTURBANCE WL ALMOST
CERTAINLY BRING ANOTHER ROUND OF MODERATE TO HEAVY LES AND SOME BLSN
MAINLY TO THE NW WIND SN BELTS NEAR LK SUP ON MON INTO TUE. YET
ANOTHER DISTURBANCE DIGGING THRU THE UPR TROF MAY BRING MORE SGNFT
LES ON WED INTO THU.
SUN...ONGOING LIGHT SN OVER THE SE CWA WL END BY EARLY IN THE AFTN
AS SHRTWV OVER ERN WI AT 12Z AND ACCOMPANYING DYNAMIC FORCING/
DEEPER MSTR EXIT TO THE E THRU LOWER MI AND INTO FAR SE ONTARIO IN
THE AFTN. AXIS OF DRIER AIR/DEEP LYR QVECTOR DVGC BTWN THIS
DEPARTING SHRTWV AND ANOTHER MORE POTENT SHRTWV DIGGING SE THRU
SCENTRAL CANADA WL THEN BRING A PERIOD OF DRY WX TO THE CWA.
ALTHOUGH H85 TEMPS ARE FCST TO BE AS LO AS -12 TO -13C...THE FCST
230 DEGREE LLVL FLOW IN ADVANCE OF THE APRCHG SHRTWV WL HOLD ANY LES
MAINLY TO THE NW OF THE KEWEENAW PENINSULA AND E OF LUCE/SCHOOLCRAFT
COUNTIES. ALTHOUGH DPVA/DEEP LYR QVECTOR CNVGC IN ADVANCE OF THE
INCOMING SHRTWV ARE FCST TO INVADE THE WRN CWA LATER IN THE DAY...
THE ABSENCE OF ANY SGNFT LLVL MSTR INFLOW WL MAINTAIN DRY WX THRU
00Z MON UNDER INCRSG HI/MID CLDS.
SUN NIGHT...INCOMING SHRTWV/SFC LO ARE FCST TO DRIFT OVER NRN LK SUP
BY 12Z MON AND CAUSE 12HR H5 HGT FALLS UP TO 120M ACROSS THE UPR
LKS. AXIS OF DPVA/DEEP LYR QVECTOR CNVGC WITHIN THE COMMA TAIL OF
THIS FEATURE ARE FCST TO SWING ACROSS UPR MI. HOWEVER...POTENTIAL
FOR WIDESPREAD SN IN ADVANCE OF THE SHRTWV WL BE LIMITED BY THE
ABSENCE OF LLVL MOISTENING/PWAT UNDER 0.25 INCH/H7 SPECIFIC HUMIDITY
NO MORE THAN ABOUT 1 G/KG. STILL LOOKS LIKE THE LLVL FLOW WL NOT
BACK SUFFICIENTLY TO ALLOW ANY LK ENHANCED OFF LK MI TO IMPACT LUCE
OR SCHOOLCRAFT COUNTIES. THE BEST CHC FOR MORE WIDESPREAD/HEAVIER
SNOW WL BE OVER THE W MAINLY LATE FOLLOWING COLD FROPA AND WIND
SHIFT TO AN UPSLOPE NW DIRECTION. ARRIVAL OF H85 TEMPS AROUND -15C
WITH SHARP CYC FLOW/LINGERING DEEP MSTR UNDER THE FALLING HGTS WILL
WARRANT KEEPING LIKELY TO CATEGORICAL POPS OVER THE W. WL GO NO HIER
THAN CHC POPS ELSEWHERE...WITH THE LOWEST SCHC POPS OVER THE
SCENTRAL.
MON/MON NGT...AS THE UPR TROF DEEPENS INTO THE GREAT LKS AND A
CLOSED H5 LO FORMS...UPR MI IS FCST TO BE UNDER SHARP...CYC W
VEERING NW FLOW ON MON AND NNW-NW FLOW ON MON NGT. FCST SDNGS SHOW
DEEP MOISTURE/INSTABILITY AS H5 TEMPS DIP TOWARD -40C. GIVEN H85
TEMPS FALLING TO -16C TO -18C AND THE DEEP INSTABILITY/MOISTURE WITH
THE CYC LLVL FLOW...CATEGORICAL POPS ARE WARRANTED IN THE FAVORED SN
BELTS. GUSTY WINDS UNDER THE SHARP PRES GRADIENT/DESTABILIZATION WL
CAUSE BLSN IN ADDITIONAL TO THE HEAVIER LES. FAVORABLE OMEGA PROFILE
WITHIN THE DGZ SITUATED BTWN ABOUT 1-5K FT AGL WL ALSO ENHANCE
SN/WATER RATIOS DESPITE THE IMPACT OF THE STRONG WINDS TO FRAGMENT
THE SN FLAKES. RIGHT NOW... THE FAR W IN ONTONAGON/GOGEBIC COUNTIES
LOOKS TO PICK UP THE HEAVIEST SN ON MON NGT...WITH ADDITIONAL HEAVY
LES IMPACTING AREAS E OF MARQUETTE LATER ON MON THRU MON NGT. LATER
SHIFTS NO DOUBT WL NEED TO HOIST LES HEADLINES. THE STRONG NW WINDS
MAY ALSO CAUSE HI ENOUGH WAVES ON LK SUPERIOR TO BRING SOME MINOR
BEACH EROSION/FLOODING IN AREAS MOST EXPOSED TO THE HIER WINDS/WAVES
BEGINNING ON LATE MON. FOR NOW...WL CONTINUE TO MENTION THE SGFNT
LES POTENTIAL/BLSN AND HI WAVES IN THE HWO PRODUCT AND EHWO GRAPHICS.
TUE/TUE NGT...AS THE CLOSED LO SHIFTS INTO QUEBEC AND 12HR H5 HGT
RISES APRCH 100M ON TUE IN THE LARGER SCALE DNVA AHEAD OF TRAILING
H5 RDG AXIS...MID LVL SUBSIDENCE/DRYING/TREND TOWARD NEUTRAL OR MORE
ACYC LLVL FLOW WL TEND TO WEAKEN THE LES W TO E. STEADILY BACKING
WINDS OVER THE W THRU THE DAY AND MAINLY DURING TUE AFTN OVER THE E
WL TEND TO LIMIT THE RESIDENCE TIME OF THE HEAVIER SN BANDS AND
SHIFT THE LES TO PRIMARILY OVER THE KEWEENAW AND TO THE E OF
MUNISING BY LATE IN THE DAY. DESPITE THIS DIMINISHING TREND...SN
TOTALS ON MON THRU TUE WL LIKELY APRCH OR EXCEED A FOOT IN THE
FAVORED SN BELTS OVER THE W CENTERED IN ONTONAGON COUNTY AND E OF
MUNISING. AS THE FLOW CONTINUES TO BACK TOWARD THE SW ON TUE NGT IN
ADVANCE OF NEXT CLIPPER SHRTWV DIGGING SEWD TOWARD MN...THE MAIN
AREA OF LES SHOULD SHIFT INTO LK SUP. BUT MORE WIDESPREAD SN MAY
ARRIVE LATE AT NGT AT LEAST OVER THE W WITH THE ONSET OF MORE
VIGOROUS DYNAMIC FORCING/HGT FALLS IN THE DPVA AHEAD OF THE NEXT
SHRTWV.
WED THRU FRI...PASSAGE OF POTENT SHRTWV/VIGOROUS DYNAMIC FORCING WL
BRING THE THREAT OF A MORE WIDESPREAD SN AGAIN ON WED DESPITE RATHER
LIMITED ABSOLUTE MSTR /FCST PWAT UNDER 0.25 INCH/. MORE LES WL BE
THE RULE ON THU INTO FRI MAINLY IN THE NW WIND SN BELTS AS ANOTHER
COLD SHOT WITH H85 TEMPS AS LO AS -16 TO -18C POURS INTO THE UPR LKS
BEHIND THE DEPARTING SHRTWV. LONGER RANGE MODELS CONTINUE TO POINT
TOWARD SOME MODERATION IN THE COLD NEXT WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 635 AM EST SAT NOV 15 2014
WESTERLY WINDS OFF LAKE SUPERIOR WILL CONTINUE TO LEAD TO LAKE
EFFECT CLOUDS (HIGH END MVFR) AND SOME SNOW SHOWERS AT KCMX THROUGH
MUCH OF THE PERIOD. CONFIDENCE IS LOW ON THE ORGANIZED NATURE OF
THE LAKE EFFECT SNOW...DUE TO THE EXISTING DRY AIR...SO WILL KEEP
VISIBILITIES AT VFR VALUES.
FOR KIWD/KSAW...EXPECT VFR CONDITIONS DUE TO UNFAVORABLE WIND
DIRECTIONS FOR LAKE EFFECT. LEFT OVER LAKE EFFECT CLOUDS FROM THE
KEWEENAW HAVE BEEN TRYING TO PUSH INTO NORTHERN MARQUETTE COUNTY
THIS MORNING. WITH WINDS OUT OF THE WEST-NORTHWEST...THEY WILL TRY
TO APPROACH KSAW BUT FEEL THEY WILL STAY MAINLY TO THE NORTH OF THE
SITE. AN APPROACHING UPPER LEVEL DISTURBANCE WILL LEAD TO
INCREASING HIGH/MID CLOUDS THIS AFTERNOON AND TONIGHT. KSAW WILL BE
THE CLOSEST FOR SOME SNOW SHOWERS AND WILL MENTION VCSH LATE TONIGHT
AS THEY APPROACH.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EST SAT NOV 15 2014
UNDER A SHARP PRES GRADIENT BETWEEN HI PRES IN THE OH RIVER VALLEY
AND LO PRES OVER HUDSON BAY...PLAN ON W WINDS UP TO 20-30KTS INTO
SUN. THE WINDS WL THEN BACK TOWARD THE SW AND DIMINISH TO UP TO
25KTS IN ADVANCE OF ANOTHER STRONG DISTURBANCE MOVING THRU SCENTRAL
CANADA AND INTO NORTHERN LAKE SUPERIOR ON MON MORNING. FOLLOWING THE
PASSAGE OF THIS LO TO THE E...THE PRES GRADIENT WILL TIGHTEN AND THE
INSTABILITY WILL INCREASE AS ANOTHER SURGE OF COLD AIR FLOWS OVER
THE RELATIVELY WARM LAKE WATERS. THE RESULT WILL BE A PERIOD OF NW
GALES ON MON INTO TUE. SINCE THIS AIRMASS WILL BE SUFFICIENTLY
COLD...THERE WILL LIKELY BE SOME FREEZING SPRAY IN SOME AREAS. THE
BEST CHANCE FOR THE GALES WILL BE OVER CENTRAL LAKE SUPERIOR. AS THE
LO PRES MOVES AWAY ON TUE AND HI PRES SHIFTS E...EXPECT THE WINDS TO
BACK TO THE W AND DIMINISH TO 25 TO 30KTS. THE PASSAGE OF ANOTHER
STRONG DISTURBANCE ON WED MAY LEAD TO ANOTHER NW GALE EVENT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KC
AVIATION...SRF
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
417 AM EST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 416 AM EST SAT NOV 15 2014
A QUIET START TO THE SHORT TERM FORECAST THIS MORNING...AS THE AREA
IS ON THE NORTHEAST EDGE OF A HIGH CENTERED FROM THE MID/UPPER
MISSISSIPPI VALLEY TO THE OHIO RIVER VALLEY. THIS HAS LED TO A
CLEAR AND COLD NIGHT ACROSS AT LEAST HALF OF THE CWA. WHERE WINDS
HAVE DECOUPLED (GENERALLY ACROSS THE INTERIOR WEST AND NEAR THE
WISCONSIN BORDER)...TEMPERATURES HAVE FALLEN INTO THE SINGLE
DIGITS BELOW ZERO. MEANWHILE...OVER THE CENTRAL AND EAST WHERE THE
WINDS HAVE BEEN STAYING UP...TEMPERATURES HAVE BEEN IN THE UPPER
SINGLE DIGITS ABOVE ZERO TO MID TEENS.
OVER LAKE SUPERIOR AND THE KEWEENAW...COLD AIR CONTINUING TO FLOW
OVER THE RELATIVELY WARM WATERS OF LAKE SUPERIOR WAS PRODUCING
MAINLY LAKE EFFECT CLOUDS THIS PAST EVENING AND INTO THE EARLY
OVERNIGHT HOURS. BUT STARTED SEEING WEAK LAKE EFFECT BANDS
OVER EASTERN LAKE SUPERIOR ON THE CANADIAN RADAR AT MONTREAL RIVER
SHORTLY AFTER MIDNIGHT. INVERSION IS RIGHT AT 875-850MB ON 00Z
KGRB/KINL SOUNDINGS AND THE LIMITED MOISTURE ON THE NORTH EDGE OF
THE HIGH HAVE BEEN THE MAIN LIMITING FACTORS TO LAKE EFFECT SNOW
EARLY THIS MORNING. KMQT VWP HAS BEEN SHOWING THE WINDS A LITTLE
MORE OUT OF THE WEST-NORTHWEST AND CONTRIBUTING TO THE LAKE EFFECT
CLOUDS NOSING SOUTHEAST INTO BARAGA...SOUTHERN HOUGHTON...AND EVEN
FAR NORTHERN IRON COUNTY EARLY THIS MORNING. BUT AS WE HEAD INTO
THE MORNING HOURS...MODELS SHOWING THE WINDS GOING BACK TO A MORE
WESTERLY AND POTENTIALLY WEST-SOUTHWESTERLY DIRECTION AND CONFINING
THE LAKE EFFECT CLOUDS AND SNOW POTENTIAL TO THE KEWEENAW AND OFF
THE SHORELINE FROM GRAND MARAIS EASTWARD. THIS WILL ALSO BE AIDED
BY THE LAND BREEZE THAT HAS DEVELOPED ALONG THE EASTERN U.P.
SHORELINE AND WILL AID IN KEEPING THE BANDS OFFSHORE THERE. THE
COVERAGE OF THE SHOWERS IS A LITTLE BIT OF A CONCERN DUE TO THE
LIMITED MOISTURE...BUT WOULD EXPECT SOME UPTICK IN THE SNOW SHOWERS
AS 875MB TEMPERATURES FALL FROM -11C ON THE RAP ANALYSIS TO -13/-14C
BY THIS AFTERNOON. THUS...WILL CONTINUE TO SHOW POPS RAMPING UP TO
HIGH CHANCES OVER THE KEWEENAW. WITH MUCH OF THE LAKE EFFECT CLOUD
BELOW THE DGZ...WILL KEEP SNOW RATIOS ON THE LOW END FOR LAKE EFFECT
AND ONLY HAVE ACCUMULATIONS AT A DUSTING TO AN INCH IN THAT AREA.
OVER THE REST OF THE AREA...EXPECT A SUNNY START TO THE DAY WHICH
WILL ALLOW TEMPERATURES TO RISE TO THE LOW-MID 20S THIS AFTERNOON.
EXPECT MORE OF A FILTERED SUNSHINE IN THE AFTERNOON AS HIGH CLOUDS
MOVE IN AHEAD OF THE WAVE BRUSHING THE AREA LATE TONIGHT.
HEADING INTO TONIGHT...FOCUS TURNS TO THE SHORTWAVE CURRENTLY
MOVING THROUGH WYOMING. THIS WAVE WILL QUICKLY SHIFT EAST THROUGH
NEBRASKA AND SOUTH DAKOTA TODAY AND THEN LIFT NORTHEAST ACROSS
NORTHERN LAKE MICHIGAN LATE TONIGHT AND SUNDAY MORNING. EXPECT THE
HIGH CLOUDS TO THICKEN THIS EVENING AND MID CLOUDS TO MOVE IN
DURING THE LATE EVENING AND OVERNIGHT. ANOTHER SHORTWAVE (CURRENTLY
IN COLORADO) WILL LIFT NORTHEAST OUT AHEAD OF THE MAIN WAVE AND
COULD PRODUCE A FEW SHOWERS AROUND MIDNIGHT. THE BETTER/MAIN
FORCING (GENERALLY ABOVE 700MB) COMES FROM THE SECOND SHORTWAVE AND
LOOKS TO STAY SOUTHEAST OF THE AREA...BUT DO EXPECT MENOMINEE COUNTY
AND AREAS ALONG THE LAKE MICHIGAN SHORELINE TO SEE THE BEST
OPPORTUNITY FOR ACCUMULATING SNOW. CURRENT FORECAST HAS SNOWFALL
AMOUNTS UP TO AN INCH OVER SOUTHERN MENOMINEE COUNTY AND TAPERING
OFF TO A HALF INCH OR LESS SOUTH OF A LINE FROM IRON MOUNTAIN TO
MANISTIQUE. SINCE THE NORTHERN EDGE OF THE FORCING WILL BE JUST
BRUSHING THE AREA...DO EXPECT A SHARP CUTOFF TO THE PRECIPITATION TO
THE NORTHWEST AND KEEP THE SNOW CHANCES TO THE SOUTHEAST OF A LINE
FROM MARQUETTE TO WATERSMEET. AS FOR THE LAKE EFFECT OVER THE
KEWEENAW...THIS WAVE WILL BACK THE LOW LEVEL WINDS FARTHER TO THE
SOUTHWEST AND FOCUS ANY LINGERING LAKE EFFECT TO THE FAR NORTHERN
PORTIONS OF THE KEWEENAW PENINSULA. ACCUMULATIONS WILL REMAIN LIGHT
AND BELOW 2 INCHES.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 409 AM EST SAT NOV 15 2014
A HI AMPLITUDE PATTERN FEATURING A TROF OVER CENTRAL AND ERN
NAMERICA DOWNSTREAM OF A RDG ALONG THE W COAST WL DOMINATE THE WX
PATTERN THIS COMING WEEK...LEADING TO PERSISTENT BLO TO WELL BLO
NORMAL TEMPS THRU THE WEEK. THE MOST SGNFT WX CONCERN WL BE THE
IMPACT OF A POTENT SHRTWV THAT IS FCST TO DIG SEWD THRU THE UPR LKS
EARLY IN THE WEEK AND AMPLIFY THE TROF. THIS DISTURBANCE WL ALMOST
CERTAINLY BRING ANOTHER ROUND OF MODERATE TO HEAVY LES AND SOME BLSN
MAINLY TO THE NW WIND SN BELTS NEAR LK SUP ON MON INTO TUE. YET
ANOTHER DISTURBANCE DIGGING THRU THE UPR TROF MAY BRING MORE SGNFT
LES ON WED INTO THU.
SUN...ONGOING LIGHT SN OVER THE SE CWA WL END BY EARLY IN THE AFTN
AS SHRTWV OVER ERN WI AT 12Z AND ACCOMPANYING DYNAMIC FORCING/
DEEPER MSTR EXIT TO THE E THRU LOWER MI AND INTO FAR SE ONTARIO IN
THE AFTN. AXIS OF DRIER AIR/DEEP LYR QVECTOR DVGC BTWN THIS
DEPARTING SHRTWV AND ANOTHER MORE POTENT SHRTWV DIGGING SE THRU
SCENTRAL CANADA WL THEN BRING A PERIOD OF DRY WX TO THE CWA.
ALTHOUGH H85 TEMPS ARE FCST TO BE AS LO AS -12 TO -13C...THE FCST
230 DEGREE LLVL FLOW IN ADVANCE OF THE APRCHG SHRTWV WL HOLD ANY LES
MAINLY TO THE NW OF THE KEWEENAW PENINSULA AND E OF LUCE/SCHOOLCRAFT
COUNTIES. ALTHOUGH DPVA/DEEP LYR QVECTOR CNVGC IN ADVANCE OF THE
INCOMING SHRTWV ARE FCST TO INVADE THE WRN CWA LATER IN THE DAY...
THE ABSENCE OF ANY SGNFT LLVL MSTR INFLOW WL MAINTAIN DRY WX THRU
00Z MON UNDER INCRSG HI/MID CLDS.
SUN NIGHT...INCOMING SHRTWV/SFC LO ARE FCST TO DRIFT OVER NRN LK SUP
BY 12Z MON AND CAUSE 12HR H5 HGT FALLS UP TO 120M ACROSS THE UPR
LKS. AXIS OF DPVA/DEEP LYR QVECTOR CNVGC WITHIN THE COMMA TAIL OF
THIS FEATURE ARE FCST TO SWING ACROSS UPR MI. HOWEVER...POTENTIAL
FOR WIDESPREAD SN IN ADVANCE OF THE SHRTWV WL BE LIMITED BY THE
ABSENCE OF LLVL MOISTENING/PWAT UNDER 0.25 INCH/H7 SPECIFIC HUMIDITY
NO MORE THAN ABOUT 1 G/KG. STILL LOOKS LIKE THE LLVL FLOW WL NOT
BACK SUFFICIENTLY TO ALLOW ANY LK ENHANCED OFF LK MI TO IMPACT LUCE
OR SCHOOLCRAFT COUNTIES. THE BEST CHC FOR MORE WIDESPREAD/HEAVIER
SNOW WL BE OVER THE W MAINLY LATE FOLLOWING COLD FROPA AND WIND
SHIFT TO AN UPSLOPE NW DIRECTION. ARRIVAL OF H85 TEMPS AROUND -15C
WITH SHARP CYC FLOW/LINGERING DEEP MSTR UNDER THE FALLING HGTS WILL
WARRANT KEEPING LIKELY TO CATEGORICAL POPS OVER THE W. WL GO NO HIER
THAN CHC POPS ELSEWHERE...WITH THE LOWEST SCHC POPS OVER THE
SCENTRAL.
MON/MON NGT...AS THE UPR TROF DEEPENS INTO THE GREAT LKS AND A
CLOSED H5 LO FORMS...UPR MI IS FCST TO BE UNDER SHARP...CYC W
VEERING NW FLOW ON MON AND NNW-NW FLOW ON MON NGT. FCST SDNGS SHOW
DEEP MOISTURE/INSTABILITY AS H5 TEMPS DIP TOWARD -40C. GIVEN H85
TEMPS FALLING TO -16C TO -18C AND THE DEEP INSTABILITY/MOISTURE WITH
THE CYC LLVL FLOW...CATEGORICAL POPS ARE WARRANTED IN THE FAVORED SN
BELTS. GUSTY WINDS UNDER THE SHARP PRES GRADIENT/DESTABILIZATION WL
CAUSE BLSN IN ADDITIONAL TO THE HEAVIER LES. FAVORABLE OMEGA PROFILE
WITHIN THE DGZ SITUATED BTWN ABOUT 1-5K FT AGL WL ALSO ENHANCE
SN/WATER RATIOS DESPITE THE IMPACT OF THE STRONG WINDS TO FRAGMENT
THE SN FLAKES. RIGHT NOW... THE FAR W IN ONTONAGON/GOGEBIC COUNTIES
LOOKS TO PICK UP THE HEAVIEST SN ON MON NGT...WITH ADDITIONAL HEAVY
LES IMPACTING AREAS E OF MARQUETTE LATER ON MON THRU MON NGT. LATER
SHIFTS NO DOUBT WL NEED TO HOIST LES HEADLINES. THE STRONG NW WINDS
MAY ALSO CAUSE HI ENOUGH WAVES ON LK SUPERIOR TO BRING SOME MINOR
BEACH EROSION/FLOODING IN AREAS MOST EXPOSED TO THE HIER WINDS/WAVES
BEGINNING ON LATE MON. FOR NOW...WL CONTINUE TO MENTION THE SGFNT
LES POTENTIAL/BLSN AND HI WAVES IN THE HWO PRODUCT AND EHWO GRAPHICS.
TUE/TUE NGT...AS THE CLOSED LO SHIFTS INTO QUEBEC AND 12HR H5 HGT
RISES APRCH 100M ON TUE IN THE LARGER SCALE DNVA AHEAD OF TRAILING
H5 RDG AXIS...MID LVL SUBSIDENCE/DRYING/TREND TOWARD NEUTRAL OR MORE
ACYC LLVL FLOW WL TEND TO WEAKEN THE LES W TO E. STEADILY BACKING
WINDS OVER THE W THRU THE DAY AND MAINLY DURING TUE AFTN OVER THE E
WL TEND TO LIMIT THE RESIDENCE TIME OF THE HEAVIER SN BANDS AND
SHIFT THE LES TO PRIMARILY OVER THE KEWEENAW AND TO THE E OF
MUNISING BY LATE IN THE DAY. DESPITE THIS DIMINISHING TREND...SN
TOTALS ON MON THRU TUE WL LIKELY APRCH OR EXCEED A FOOT IN THE
FAVORED SN BELTS OVER THE W CENTERED IN ONTONAGON COUNTY AND E OF
MUNISING. AS THE FLOW CONTINUES TO BACK TOWARD THE SW ON TUE NGT IN
ADVANCE OF NEXT CLIPPER SHRTWV DIGGING SEWD TOWARD MN...THE MAIN
AREA OF LES SHOULD SHIFT INTO LK SUP. BUT MORE WIDESPREAD SN MAY
ARRIVE LATE AT NGT AT LEAST OVER THE W WITH THE ONSET OF MORE
VIGOROUS DYNAMIC FORCING/HGT FALLS IN THE DPVA AHEAD OF THE NEXT
SHRTWV.
WED THRU FRI...PASSAGE OF POTENT SHRTWV/VIGOROUS DYNAMIC FORCING WL
BRING THE THREAT OF A MORE WIDESPREAD SN AGAIN ON WED DESPITE RATHER
LIMITED ABSOLUTE MSTR /FCST PWAT UNDER 0.25 INCH/. MORE LES WL BE
THE RULE ON THU INTO FRI MAINLY IN THE NW WIND SN BELTS AS ANOTHER
COLD SHOT WITH H85 TEMPS AS LO AS -16 TO -18C POURS INTO THE UPR LKS
BEHIND THE DEPARTING SHRTWV. LONGER RANGE MODELS CONTINUE TO POINT
TOWARD SOME MODERATION IN THE COLD NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1153 PM EST FRI NOV 14 2014
WESTERLY WINDS ACROSS LAKE SUPERIOR AND SUFFICIENTLY COLD AIR WILL
SUPPORT BKN-OVC MVFR CIGS AT KCMX THRU THE FCST PERIOD. OCNL
FLURRIES/-SHSN ARE EXPECTED AS WELL. AT KIWD/KSAW...VFR CONDITIONS
WILL PREVAIL THRU THE FCST PERIOD UNDER A RELATIVELY DRY AIR MASS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EST SAT NOV 15 2014
UNDER A SHARP PRES GRADIENT BETWEEN HI PRES IN THE OH RIVER VALLEY
AND LO PRES OVER HUDSON BAY...PLAN ON W WINDS UP TO 20-30KTS INTO
SUN. THE WINDS WL THEN BACK TOWARD THE SW AND DIMINISH TO UP TO
25KTS IN ADVANCE OF ANOTHER STRONG DISTURBANCE MOVING THRU SCENTRAL
CANADA AND INTO NORTHERN LAKE SUPERIOR ON MON MORNING. FOLLOWING THE
PASSAGE OF THIS LO TO THE E...THE PRES GRADIENT WILL TIGHTEN AND THE
INSTABILITY WILL INCREASE AS ANOTHER SURGE OF COLD AIR FLOWS OVER
THE RELATIVELY WARM LAKE WATERS. THE RESULT WILL BE A PERIOD OF NW
GALES ON MON INTO TUE. SINCE THIS AIRMASS WILL BE SUFFICIENTLY
COLD...THERE WILL LIKELY BE SOME FREEZING SPRAY IN SOME AREAS. THE
BEST CHANCE FOR THE GALES WILL BE OVER CENTRAL LAKE SUPERIOR. AS THE
LO PRES MOVES AWAY ON TUE AND HI PRES SHIFTS E...EXPECT THE WINDS TO
BACK TO THE W AND DIMINISH TO 25 TO 30KTS. THE PASSAGE OF ANOTHER
STRONG DISTURBANCE ON WED MAY LEAD TO ANOTHER NW GALE EVENT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KC
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
351 PM CST SAT NOV 15 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 351 PM CST SAT NOV 15 2014
STEADY LIGHT SNOW HAS ENGULFED SOUTHERN MN IN LIGHT SNOW THROUGH THE
DAY...WITH THE HEAVIEST BAND SETTING UP ALONG THE IOWA BORDER AS
EXPECTED. FOR THE REMAINDER OF THE AFTERNOON...WE`RE EXPECTING MOST
OF THE SNOW IN SOUTHERN MN TO WEAKEN AS FORCING WANES...AND THE
F-GEN MAX SLIDES SOUTH INTO IOWA...AS FRONTOLYSIS TAKES OVER ACROSS
WEST CENTRAL THROUGH SOUTHERN MN. THIS TREND IS QUITE APPARENT ON
RADAR AND HAS BEEN HANDLED WELL BY THE HRRR FOR THE LAST SEVERAL
RUNS. SO...EXPECT A LULL FOR MUCH OF THE AFTERNOON AND THE EVENING.
ANOTHER DECENT SNOW BAND WILL DEVELOP LATER TONIGHT. IT WILL CROSS
THE MN/SD BORDER AROUND 6-7 PM AND CONTINUE EASTWARD...PRODUCING
LIGHT ACCUMULATIONS ACROSS THE SOUTHERN HALF OF THE STATE AND
THROUGH WEST CENTRAL WI. FOR THE TWIN CITIES...THIS BAND WILL
PRODUCE AN ADDITIONAL 0.5"-1" MAINLY FROM 9PM THROUGH 1AM.
CURRENTLY EXPECTING THE BACK EDGE OF THIS BAND TO CROSS THE MN/WI
LINE AT ABOUT 3AM...WITH LIGHT SNOW LINGERING UNTIL 5-6AM NEAR EAU
CLAIRE.
OVERNIGHT TEMPERATURES LAST NIGHT WERE A GOOD FIVE DEGREES COLDER
THAN EXPECTED OVER THE SOLID SNOW PACK. IN COLLABORATION WITH OTHER
OFFICES...WENT SLIGHTLY COOLER ACROSS THE WEST THAN MOST OF THE
GUIDANCE...BUT THE EASTERN CWA WILL RETAIN SOMEWHAT WARMER
TEMPERATURES UNDER CONSISTENT CLOUD COVER /AND LINGERING LIGHT
PRECIP OVERNIGHT/. BY TOMORROW MORNING...WINDS WILL HAVE TURNED
WESTERLY AND WILL INCREASE THROUGH THE DAY. STRONG CAA APPARENT AT
925H ON THE BACKSIDE OF THE WAVE WILL MAKE FOR A COLD SUNDAY. 925H
TEMPS AROUND -12C ACROSS MOST OF THE REGION WILL ONLY ALLOW SURFACE
TEMPS TO MIX INTO THE UPPER TEENS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 351 PM CST SAT NOV 15 2014
THE WEEK AHEAD REMAINS EXTREMELY COLD FOR MID NOVEMBER WITH THREE
SURGES OF ARCTIC AIR FORECAST ACROSS THE UPPER MISSISSIPPI VALLEY.
THE FIRST IS SUNDAY NIGHT/MONDAY...THE SECOND TUESDAY NIGHT/WEDNESDAY
WITH THE THIRD ON THURSDAY. LOWS/HIGHS THROUGH THE PERIOD WILL
CONTINUE TO AVERAGE SOME 20 TO 30 DEGREES BELOW NORMAL. THE TREND
TODAY WAS TO CONTINUE LOWERING TEMPERATURES OVER THE BLENDED
GUIDANCE DUE TO A MORE EXPANSIVE SNOW PACK. THE ARCTIC SURGE THAT
OCCURS SUNDAY NIGHT/MONDAY OFFERS THE BEST CHANCE FOR SNOW
SHOWERS...ESPECIALLY ACROSS CENTRAL MINNESOTA AND WEST CENTRAL
WISCONSIN...WHERE A FLUFFY INCH OR TWO COULD OCCUR. THE OTHER TWO
ARCTIC SURGES HAVE THE BETTER MOISTURE AND FORCING TO THE NORTHEAST
OF OUR FORECAST AREA RESULTING IN LESS CHANCES FOR SNOW FOR US.
THE MAIN CONCERN IN THE LONG TERM IS THE BLOWING SNOW POTENTIAL IN
THE MINNESOTA RIVER VALLEY SUNDAY NIGHT AND MONDAY. THE CONCERN
FOR BLIZZARD CONDITIONS DEVELOPING ON MONDAY HAS WANED A BIT TODAY
AS ALL OF THE DETERMINISTIC MODELS HAVE DECREASED THE SURFACE
PRESSURE GRADIENT ACROSS THE MN FORECAST AREA FROM 10 MB TO 8 MB IN
THE PAST 24 HOURS. THIS HAS LOWERED WIND SPEED FORECASTS A LITTLE
ON MONDAY FROM KRWF TO KFRM. IN ADDITION...SNOWFALL ACCUMULATION
SO FAR TODAY HAS BEEN HIGHEST IN EASTERN SOUTH DAKOTA AND FAR
SOUTHWEST MINNESOTA (OUTSIDE OF OUR FORECAST AREA) WHERE 3 TO 5
INCHES HAVE BEEN COMMON. SNOWFALL IN OUR AREA OF WEST CENTRAL
THROUGH SOUTH CENTRAL MINNESOTA HAS BEEN MORE IN THE 1 TO 3 INCH
RANGE.
BUFKIT PROFILES FROM BOTH THE NAM AND GFS SHOW THAT THE BEST LOW
LEVEL LAPSE RATES AND HIGHEST TOP OF THE CHANNEL MOMENTUM TRANSFER
DON/T OCCUR UNTIL LATE MONDAY MORNING AND AFTERNOON FROM WEST
CENTRAL THROUGH SOUTH CENTRAL MINNESOTA. ALTHOUGH AREAS OF
BLOWING SNOW WILL BEGIN ACROSS WEST CENTRAL THROUGH SOUTH CENTRAL
MINNESOTA SUNDAY NIGHT IN THE WAKE OF THE ARCTIC FRONT...THERE
ARE STILL SOME INDICATIONS THAT SUSTAINED WIND SPEEDS COULD REACH
25 MPH FROM KRWF TO KFRM MONDAY AFTERNOON WITH GUSTS HITTING 40
MPH. THIS COULD RESULT IN NEAR BLIZZARD CONDITIONS FOR A COUPLE OF
HOURS IN THESE AREAS. COMPLICATING MATTERS IS THE THREAT FOR SNOW
SHOWERS ALONG WITH THE SATURATED LOW LEVEL CONDITIONS REMAINING IN
THE DENDRITIC GROWTH ZONE.
AT THIS POINT...DIDN/T HAVE ENOUGH CONFIDENCE TO ISSUE A BLIZZARD
WATCH FOR MONDAY FROM YELLOW MEDICINE AND RENVILLE COUNTIES ON
SOUTHEAST TO MARTIN AND FARIBAULT WITH THE PRESSURE GRADIENT
WEAKENING SOME AND THE HIGHER SNOW TOTALS TODAY TO OUR WEST. THERE
IS STILL PLENTY OF TIME LATER TONIGHT TO ISSUE A WATCH IF WIND
CONDITIONS CHANGE WITH THE 00Z MODEL RUNS. OTHERWISE...A WINTER
WEATHER ADVISORY FOR BLOWING SNOW WILL LIKELY BE ISSUED ON SUNDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1145 AM CST SAT NOV 15 2014
SNOW FORECAST REMAINS ON TRACK TODAY. ALREADY A FEW INCHES OF
ACCUMULATION HAS BEEN REPORTED ALONG THE IOWA BORDER. THAT AREA
IS STILL ULTIMATELY EXPECTED TO RECEIVE THE HIGHEST
ACCUMULATIONS...IN THE 3-6" RANGE BY TOMORROW MORNING. WIDESPREAD
IFR VIS EXPECTED TO CONTINUE THROUGH EARLY AFTERNOON...AND
GUIDANCE CONTINUES TO INDICATE SNOW INTENSITIES WILL LIGHTEN UP
FOR A PERIOD THIS AFTERNOON AS THE BEST PRE FRONTAL FORCING SHIFTS
AWAY TO THE SOUTHEAST. THIS EVENING THOUGH...THE FORCING
ASSOCIATED WITH THE MAIN WAVE WILL MOVE THROUGH SOUTHERN MN AND WE
SHOULD SEE RADAR RETURNS INTENSIFY SOME. INDICATED THIS IN MANY
SITES WITH A RISE IN VSBY DURING THE LATE AFTERNOON...BUT EXPECT
THOSE TO RETURN TO IFR TONIGHT. AS FAR AS EXTENT OF THE SNOW...AXN
WILL BE LEAST AFFECTED WITH BR OR HAZE BEING MORE OF A VSBY
REDUCTION THAN PURE SNOWFALL. LOOKING FOR THE SNOW TO END
OVERNIGHT FROM WEST TO EAST...REACHING THE WI BORDER BY AROUND
09Z-10Z. AFTER THAT...A FEW HOURS OF MVFR CIGS FOLLOWED BY VFR FOR
MOST AREAS THROUGH THE MORNING ON SUNDAY. WE`LL START TO SEE SW
WINDS INCREASING AND BECOMING GUSTY LATE IN THE MORNING AND INTO
THE AFTERNOON.
KMSP...VSBY REDUCTIONS SO FAR IN LARGE PART DUE TO BR...SO NOT
MUCH ACCUMULATION DESPITE VSBYS AROUND 1SM FOR THE LAST FEW HOURS.
STILL EXPECT A BIT OF A LULL THIS AFTERNOON...WITH
RE-INTENSIFICATION LATE TONIGHT AS THE MAIN WAVE MOVES THROUGH.
STILL EXPECT AROUND AN INCH OF ACCUMULATION AT THE AIRFIELD WHEN
ITS ALL SAID AND DONE.
/OUTLOOK FOR KMSP/
MON...SLIGHT CHC -SN WITH IFR/MVFR CIGS. WINDS NW 15-20 G 25 KTS.
TUE...VFR. WINDS W 10-15 KTS.
WED...VFR. WINDS NW 10-15 KTS G 20 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR
MNZ073>076-082>085-091>093.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...RAH
AVIATION...SPD
AREA FORECAST DISCUSSION
NWS JACKSON MS
1050 AM CST SAT NOV 15 2014
.UPDATE...
FORECAST IS ON TRACK WITH ONLY ADJUSTMENTS MADE TO CLOUD COVER FOR
TODAY.
&&
.DISCUSSION...
WEAK ISENTROPIC LIFT IN 285-290K LAYER IS SUPPORTING CLOUD DECK
MOVING INTO NE LA/SE AR AND SW MS...BUT MOST RECENT HRRR GUIDANCE
INDICATES THE DECK WILL DISSIPATE BEFORE GETTING INTO CENTRAL/ERN MS
THIS AFTN WHERE HIGHER CONDENSATION PRESSURE DEFICITS AND NEUTRAL
PRESSURE ADVECTION ARE FORECAST. HAVE INCREASED THE CLOUD GRADIENT
ACROSS THE AREA KEEPING EASTERN MS SUNNY. INCREASED CLOUD COVER OVER
WESTERN PORTIONS OF THE AREA SHOULD NOT KEEP TEMPERATURES DOWN TOO
MUCH GIVEN INCREASED SE SFC FLOW. /EC/
&&
.AVIATION...VFR CONDITIONS WILL PREVAIL THROUGH THE EVENING HOURS AT
MOST AREA TERMINALS. DURING THE LATE OVERNIGHT OR EARLY SUNDAY
MORNING...CIGS WILL BEGIN TO LOWER WITH RAIN BEGINNING TO SRPEAD
ACROSS THE AREA. MVFR CEILINGS WILL BECOME LIKELY AFTER DAYBREAK...
POSSIBLY LOWERING TO IFR LATER IN THE DAY. THERE WILL ALSO BE
OCCASIONAL REDUCTIONS TO MVFR VISIBILITY IN HEAVIER RAINFALL DURING
THE DAY SUNDAY. /DL/
&&
.PREV DISCUSSION... /ISSUED 425 AM CST SAT NOV 15 2014/
SHORT TERM...GOOD RADIATIONAL COOLING NIGHT UNDERWAY ACROSS THE
AREA AS TEMPS HAVE SETTLED AS EXPECTED IN THE MID/UPPER 20S. THE
EXCEPTION HAS BEEN OVER FAR SW PORTIONS WHERE EASTWARD FRINGES OF
LOW CLOUD DECK OVER TX/LA HAVE KEPT TEMPS FROM FALLING OFF TO THEIR
FULL POTENTIAL.
CLOUD DECK OVER TX/LA IS A RESULT OF THE BEGINNINGS OF LOW LEVEL
ISENTROPIC ASCENT IN ADVANCE OF DIGGING SYSTEM OVER THE ROCKIES.
THIS DECK WILL ONLY THICKEN AND CONTINUE SPREADING EAST TODAY.
VEERING LOW LEVEL WINDS ALONG THE UPPER TX/LA COASTS TODAY WILL
INTERACT WITH COASTAL BAROCLINIC ZONE LEADING TO FRONTOGENESIS AND A
SURGING WARM FRONT NORTHWARD OVERNIGHT. AS DEEP LAYER SOUTHERLY FLOW
INCREASES...GOOD ISENTROPIC ASCENT WILL ALLOW RAIN TO BEGIN BREAKING
OUT FROM THE WEST MAINLY AFTER MIDNIGHT.
AS THE MID/UPPER LEVEL SYSTEM PULLS OUT OF THE PLAINS INTO THE LOWER
MS VALLEY SUNDAY...INCREASING DIFFLUENCE ALOFT WILL LEAD TO SURFACE
CYCLOGENESIS ALONG THE BOUNDARY OVER CENTRAL LA. AS THIS OCCURS THE
FRONTOGENETICAL FORCING WILL DRASTICALLY INCREASE...ESPECIALLY TO
THE NORTH AND EAST OF THE SURFACE LOW. WITH DEEP MOISTURE ALREADY IN
PLACE...THE ORIENTATION OF THETA-E WILL BE NEARLY UPRIGHT OVER THE
TOP OF THE BOUNDARY. THIS SHOULD EASILY LEAD TO FORCED CONVECTION
WITH THE 50+ KNOT FLOW BOUND TO THETA-E SURFACES. WHILE SOUNDINGS
FOR THE MOST PART WILL BE MOIST ADIABATIC...MODELS SOUNDINGS AND
PROFILES ARE SHOWING SOME MAUL POTENTIAL IN THE H8-H6 LAYER DUE TO
STRONG CONDENSATIONAL LATENT HEATING OVERTOP THE BOUNDARY. THIS WILL
LEAD TO SOME RATHER ROBUST UPDRAFTS WITH THE POSSIBILITIES FOR
SPORADIC THUNDER AND PERIODS OF HEAVY RAIN SUNDAY AFTERNOON AND
NIGHT. DESPITE THE RECENT DRY SPELL RAINFALL RATES MAY BE HIGH
ENOUGH IN SPOTS TO CAUSE AT LEAST MINOR ISOLATED FLOODING
WORRIES...AND THIS WILL BE ADDRESSED IN THE HWO.
NAM AND ECMWF ARE SUGGESTING THAT THE WARM SECTOR WILL SURGE NORTH
SUNDAY NIGHT WITH CAPES AOB 500 J/KG AND 35 TO 45 KNOTS OF 0-1KM
BULK SHEAR AS FAR NORTH AS A BROOKHAVEN TO QUITMAN LINE. WILL NOT
ADD ANYTHING TO THE HWO AT THE MOMENT...BUT TRENDS WILL NEED TO BE
MONITORED CLOSELY./26/
LONG TERM...MONDAY THROUGH THE END OF NEXT WEEK...BIG COLD FRONT
SHOULD BE RAPIDLY CLEARING EAST OF THE REGION MONDAY MORNING WITH
POST FRONTAL RAIN SHOWERS TAILING OFF QUICKLY FROM WEST TO EAST IN
THE MORNING AS WELL. FOR OUR REGION...CURRENT EXPECTATIONS ARE THAT
COLD AIR BEHIND THE COLD FRONT WILL NOT BE COMING IN QUICKLY ENOUGH
TO WORRY ABOUT ANY BRIEF CHANGEOVER TO FLURRIES BEFORE PRECIPITATION
ENDS (EVEN IN MY NORTHERN ZONES). CLEARING SHOULD TAKE PLACE BY
MONDAY AFTERNOON AT THE LATEST ALTHOUGH A GUSTY NORTHWEST WIND WILL
BE VERY COLD AND BITING.
EARLY SEASON MODIFYING ARCTIC AIR FUNNELING SOUTH INTO THE ARKLAMISS
LATE MONDAY MIGHT NOT MODIFY AS MUCH AS USUALLY WOULD BE THE CASE
OWING TO A LITTLE SNOWCOVER NOT TOO FAR UPSTREAM. THIS WILL LEND TO
ANOTHER STRETCH OF UNSEASONABLY COLD CONDITIONS...ALTHOUGH
FORTUNATELY WITH NOT QUITE THE STAYING POWER AS THE CURRENT STRETCH.
LOWS EARLY TUESDAY MORNING MIGHT FLIRT WITH THE UPPER TEENS IN A FEW
NORTHERN ZONES WHILE ALL OTHER AREAS SEE MINIMUMS IN THE 20S. SOME
RETURN FLOW DEVELOPING IN WESTERN ZONES BY TUESDAY NIGHT MAY LIMIT
RADIATIONAL COOLING THERE A BIT...BUT NOT ELSEWHERE WHERE LOWS WAY
DOWN IN THE 20S LOOK A SOLID BET AGAIN.
WE WILL START WARMING UP...ALBEIT NOT TERRIBLY QUICKLY...COME
WEDNESDAY AS COLD HIGH PRESSURE SHUFFLES OFF TO THE EAST AND BUILDS
SOUTH TO SOUTHWEST FLOW IN THE LOWER LEVELS. SUBTLE WAVES OF
SOUTHERN STREAM ENERGY MAKING THEIR WAY HERE BY THURSDAY AND THROUGH
THE REST OF THE WEEK WILL PROBABLY HAVE ENOUGH MOISTURE TO WORK WITH
TO GENERATE AT LEAST A FEW SHOWERS. THERE IS STILL SOME POSSIBILITY
OF A DECENT LOW SPINNING UP AND TRACKING TO OUR NORTHWEST SOMETIME
NEXT WEEKEND ALTHOUGH MODEL CONSENSUS IN THIS POTENTIALLY STORMY
DIRECTION IS NOT THE BEST. ADDING TO THE UNCERTAINTY AT THE END OF
NEXT WEEK IS THE LATEST OPERATIONAL EURO RUN SUGGESTING ANOTHER DEEP
ARCTIC INCURSION MAY PUT A SERIOUS HALT TO ANY WARMING TREND BY NEXT
SATURDAY. ANY CONSENSUS TREND TOWARD THIS OUTLYING SOLUTION WOULD OF
COURSE BE WATCHED CLOSELY. /BB/
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
923 PM CST Sun Nov 16 2014
.UPDATE:
Issued at 923 PM CST Sun Nov 16 2014
Accumulating snow has ended across the area allowing the winter
weather advisory to expire at 9 pm. The band of accumulating snow
continues just south of the CWA which is being forced by strong
frontogenesis that will eventually shift southeast tonight. Some
snow may still occur along and south of a Fredericktown to Salem,
IL line on the northern periphery of this area of snow before
08Z per the HRRR, but any accumulation is expected to be minor.
Temperatures are falling into the teens over northeast Missouri,
and decent cold air advection should allow most of the area to
fall into the teens before sunrise.
Britt
&&
.SHORT TERM: (Through Late Tonight)
Issued at 345 PM CST Sun Nov 16 2014
Snow is clearing from the west to east this afternoon, and latest
short-range guidance shows that it should continue to push east at a
decent clip through early evening. RAP and HRRR have done a very
good job with this system (as they did with yesterday`s
precipitation) so am following them closely. The surface cold front
which currently looks to be along a line from near Pittsfield to
near the Lake of the Ozarks, will push slowly eastward tonight.
While accumulating snow should end across most of the area by
00-02Z, some flurries could linger along and east of the Mississippi
from St. Louis southward until the cold front finally pushes through
bringing drier low level air to the area. An additional 1-2 inches
of snow with locally higher amounts is still possible until the
snow ends...primarily on elevated surfaces. Based on current obs
and latest radar trends, will be dropping the advisory west and
north of the STL area, while continuing the advisory into the
early evening hours over southeast sections of the CWA.
Guidance appears to have a reasonable handle on overnight lows.
Leading edge of the first round of Arctic air (as defined by
single digits dewpoints) currently entering northwest sections of
the CWA, and this will be followed by a secondary surge of Arctic
air (now working into the mid-Missouri Valley) that will enter the
CWA during the predawn hours. In this situation guidance has a tendency
to be a bit too cool due to mixing and some clouds, but due to the
shear strength of cold air in this situation believe "thinking
cold" is the way to go.
Carney/Truett
.LONG TERM: (Monday through Next Sunday)
Issued at 313 PM CST Sun Nov 16 2014
Monday-Wednesday
Deep and unseasonably strong UA trof over the eastern half of the
CONUS will mean more unseasonably cold November temperatures in
our area through midweek. Obviously, temperature specifics are
going to be the main forecast problem in the short term, and going
forecasts appear to have a fairly good handle on the expected
trends.
Secondary surge of Arctic air that enters the FA late tonight
will be a much colder airmass than any we`ve experienced during
this early taste of winter, and there is good agreement in the 12z
synoptic runs that 850mb temps of -18 to -20C will be common over
the mid-Mississippi Valley by Monday evening. Low level RH progs
suggest quite a bit of low level cloudiness overspreading the area
on Monday in the wake of the secondary cold front, and this cloud
cover combined with the very cold airmass will almost certainly
mean highs only in the 20s for most of the CWA. Perhaps the
biggest question is Monday night. While airmass is extremely cold
for this time of year and there may be snow on the ground in some
locations over the southeast half of the CWA, the center of the
Arctic high is forecast to drop from the Plains into the Arklatex
region. The resultant pressure gradient in our area should mean
that westerly winds will persist throughout much of the night,
with this mixing keeping low temps from reaching record levels.
Normally in this situation would be worried about climo bias
causing guidance to be too warm, but due to the aforementioned
winds and mixing believe it may have a good handle on Monday
night temp trends at this point in time. See climate section for
more info on record lows/record low max temps for the next few
days/nights.
AMS moderation will begin on Tuesday as the center of the Arctic
high works its way in the the se U.S., with additional warming on
Wednesday due to warm advection ahead of next shortwave.
Precipitation threat over the next few days should be limited to a
few flurries with the arrival of the cold air and low clouds
tomorrow.
Thursday-Sunday
Another shot of cold air will settle into the region in the wake of
Wednesday`s shortwave. However, this next round of cold air will
not be nearly as strong as the Arctic airmass that invades the region
tomorrow and tomorrow night, and as a result it`s impact on late
week temps will not be nearly as dramatic.
Temperatures will moderate heading into next weekend as trof axis
works east and allows a more zonal flow regime to develop over the
nation`s heartland. Resultant low level warm advection/isentropic
ascent, combined with an approach of an upper level trof in the
southern branch of the westerlies, should mean a chance of
precipitation. Last several medium range runs, as well as latest
12z guidance, suggests ams will warm enough that the bulk of this
precip will be in liquid form.
Truett
&&
.AVIATION: (For the 00z TAFs through 00z Monday Evening)
Issued at 544 PM CST Sun Nov 16 2014
Snow has come to an end at KCOU and KUIN, but some lingering light
snow and flurries in STL metro area through 01z. Otherwise, as
cold front moves through cigs to lift to vfr. So KCOU to remain
vfr while KUIN to improve by 01z and metro to lift and improve by
05z. By mid morning on Monday, northwest winds to pickup to around
15kts with gusts to 25kts at times. Will see sc deck develop on
back side of system, so added tempo mention of mvfr cigs for the
afternoon hours.
Specifics for KSTL:
Some lingering light snow and flurries in STL metro area through
01z. Otherwise, as cold front moves through cigs to lift to vfr.
So cigs to lift and improve by 05z. By 16z Monday, northwest winds
to pickup to around 15kts with gusts to 25kts at times. Will see
sc deck develop on back side of system, so added tempo mention of
mvfr cigs for the afternoon hours.
Byrd
&&
.CLIMATE:
The following are record low maximums and record low minimums for
each of the next 3 days, which corresponds to the expected length
of the current cold spell and record snowfall for St. Louis and
Columbia for Sunday and Monday.
Date: 11/16 11/17 11/18
St. Louis
Low High: 29/1997 17/1880 25/1880
Low: 13/1959 6/1959 14/1932
Snowfall: 0.1/1997 1.0/1951
Columbia
Low High: 30/1932 23/1959 27/1903
Low: 8/1959 4/1959 8/1891
Snowfall: 4.8/1932 0.1/1989
Quincy
Low High: 28/1997 19/1959 24/1903
Low: 4/1959 3/1959 7/1903
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
555 PM CST Sun Nov 16 2014
.SHORT TERM: (Through Late Tonight)
Issued at 345 PM CST Sun Nov 16 2014
Snow is clearing from the west to east this afternoon, and latest
short-range guidance shows that it should continue to push east at a
decent clip through early evening. RAP and HRRR have done a very
good job with this system (as they did with yesterday`s
precipitation) so am following them closely. The surface cold front
which currently looks to be along a line from near Pittsfield to
near the Lake of the Ozarks, will push slowly eastward tonight.
While accumulating snow should end across most of the area by
00-02Z, some flurries could linger along and east of the Mississippi
from St. Louis southward until the cold front finally pushes through
bringing drier low level air to the area. An additional 1-2 inches
of snow with locally higher amounts is still possible until the
snow ends...primarily on elevated surfaces. Based on current obs
and latest radar trends, will be dropping the advisory west and
north of the STL area, while continuing the advisory into the
early evening hours over southeast sections of the CWA.
Guidance appears to have a reasonable handle on overnight lows.
Leading edge of the first round of Arciic air (as defined by
single digits dewpoints) currently entering northwest sections of
the CWA, and this will be followed by a secondary surge of Arctic
air (now working into the mid-Missouri Valley) that will enter the
CWA during the predawn hours. In this situation guidance has a tendency
to be a bit too cool due to mixing and some clouds, but due to the
shear strength of cold air in this situation believe "thinking
cold" is the way to go.
Carney/Truett
.LONG TERM: (Monday through Next Sunday)
Issued at 313 PM CST Sun Nov 16 2014
Monday-Wednesday
Deep and unseasonably strong UA trof over the eastern half of the
CONUS will mean more unseasonably cold November temperatures in
our area through midweek. Obviously, temperature specifics are
going to be the main forecast problem in the short term, and going
forecasts appear to have a fairly good handle on the expected
trends.
Secondary surge of Arctic air that enters the FA late tonight
will be a much colder airmass than any we`ve experienced during
this early taste of winter, and there is good agreement in the 12z
synoptic runs that 850mb temps of -18 to -20C will be common over
the mid-Mississippi Valley by Monday evening. Low level RH progs
suggest quite a bit of low level cloudiness overspreading the area
on Monday in the wake of the secondary cold front, and this cloud
cover combined with the very cold airmass will almost certainy
mean highs only in the 20s for most of the CWA. Perhaps the
biggest question is Monday night. While airmass is extremely cold
for this time of year and there may be snow on the ground in some
locations over the southeast half of the CWA, the center of the
Arctic high is forecast to drop from the Plains into the Arklatex
region. The resultant pressure gradient in our area should mean
that westerly winds will persist throughout much of the night,
with this mixing keeping low temps from reaching record levels.
Normally in this situation would be worried about climo bias
causing guidance to be too warm, but due to the aforementioned
winds and mixing believe it may have a good handle on Monday
night temp trends at this point in time. See climate section for
more info on record lows/record low max temps for the next few
days/nights.
AMS moderation will begin on Tuesday as the center of the Arctic
high works its way in the the se U.S., with additional warming on
Wednesday due to warm advection ahead of next shortwave.
Precipitation threat over the next few days should be limited to a
few flurries with the arrival of the cold air and low clouds
tomorrow.
Thursday-Sunday
Another shot of cold air will settle into the region in the wake of
Wednesday`s shortwave. However, this next round of cold air will
not be nearly as strong as the Artic airmass that invades the region
tomorrow and tomorrow night, and as a result it`s impact on late
week temps will not be nearly as dramatic.
Temperatures will moderate heading into next weekend as trof axis
works east and allows a more zonal flow regime to develop over the
nation`s heartland. Resultant low level warm advection/isentropic
ascent, combined with an approach of an upper level trof in the
southern branch of the westerlies, should mean a chance of
precipitation. Last several medium range runs, as well as latest
12z guidance, suggests ams will warm enough that the bulk of this
precip will be in liquid form.
Truett
&&
.AVIATION: (For the 00z TAFs through 00z Monday Evening)
Issued at 544 PM CST Sun Nov 16 2014
Snow has come to an end at KCOU and KUIN, but some lingering light
snow and flurries in STL metro area through 01z. Otherwise, as
cold front moves through cigs to lift to vfr. So KCOU to remain
vfr while KUIN to improve by 01z and metro to lift and improve by
05z. By mid morning on Monday, northwest winds to pickup to around
15kts with gusts to 25kts at times. Will see sc deck develop on
back side of system, so added tempo mention of mvfr cigs for the
afternoon hours.
Specifics for KSTL:
Some lingering light snow and flurries in STL metro area through
01z. Otherwise, as cold front moves through cigs to lift to vfr.
So cigs to lift and improve by 05z. By 16z Monday, northwest winds
to pickup to around 15kts with gusts to 25kts at times. Will see
sc deck develop on back side of system, so added tempo mention of
mvfr cigs for the afternoon hours.
Byrd
&&
.CLIMATE:
The following are record low maximums and record low minimums for
each of the next 3 days, which corresponds to the expected length
of the current cold spell and record snowfall for St. Louis and
Columbia for Sunday and Monday.
Date: 11/16 11/17 11/18
St. Louis
Low High: 29/1997 17/1880 25/1880
Low: 13/1959 6/1959 14/1932
Snowfall: 0.1/1997 1.0/1951
Columbia
Low High: 30/1932 23/1959 27/1903
Low: 8/1959 4/1959 8/1891
Snowfall: 4.8/1932 0.1/1989
Quincy
Low High: 28/1997 19/1959 24/1903
Low: 4/1959 3/1959 7/1903
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...WINTER WEATHER ADVISORY until 9 PM CST this evening FOR Iron MO-
Madison MO-Reynolds MO-St. Francois MO-Ste. Genevieve MO.
WINTER WEATHER ADVISORY until 6 PM CST this evening FOR
Jefferson MO-St. Louis City MO-St. Louis MO.
IL...WINTER WEATHER ADVISORY until 9 PM CST this evening FOR Bond IL-
Clinton IL-Fayette IL-Madison IL-Marion IL-Monroe IL-
Randolph IL-St. Clair IL-Washington IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
421 PM CST Sat Nov 15 2014
.DISCUSSION...
Issued at 418 PM CST SAT NOV 15 2014
Tonight - Sunday:
As today`s system which generated 2-4 inches of snow over the far
northern counties exits the region our attention turns to three
secondary areas of snow. An area of snow over Nebraska is tied to a
shortwave trough moving east through western SD/NE. The trailing
band of enhanced clouds/snow is expected to drag through the CWA
overnight but only the far northwestern counties have a chance of
more than a dusting...maybe 1/2" to and inch. The expected band of
snow should diminish in intensity overnight but most areas will see
at least intermittent flurries.
The second region of snow is a result of the seeder-feeder mechanism
as noted by the broken area of enhanced mid clouds which have formed
from east central KS into west central MO. There likely is a weak
mid-level vorticity max tied to this region of cloud and the NAM h7
prog seems to hint on this. Only the short-range HRRR has picked up
on this. Could get a quick half inch of snow across the far southern
CWA during the late afternoon/early evening hours before the feature
weakens as it quickly heads east.
The third area of snow is expected to form over the CO Rockies
tonight and rapidly expand as a narrow band in response to the left
front quad of an upper level jet streak races through the Central
Rockies and into KS/OK Sunday morning. Operational models do depict
one or two vorticity lobes tracking into the region within an
overall area of ascent. At this time the northern edge of the
expected snow band could skirt across our far southern counties so
have added chance PoPs to this area.
Otherwise, until the primary upper trough passes through late on
Sunday am expecting mostly cloudy skies for most of the CWA. This
will mute the diurnal temperature range.
Monday - Tuesday:
Much below average temperatures will continue during this period
with the potential for a record low max temperature on Monday and
record setting lows Tuesday morning. Another upper trough will dig
southward Sunday night and Monday and result in falling mid/upper
level heights and enhance the flow of Arctic air southward from the
Canadian Plains to central U.S. Another surge of this air will move
in during this period. Steep lapse rates below 750mb and a moist
layer residing within the boundary layer suggests a good chance for
instability snow showers or flurries Monday afternoon.
Wednesday - Saturday:
This should be a dry period with a continuation of the unseasonably
cold regime. Cyclonic/northwest flow aloft will continue featuring
the potential for weak embedded shortwaves to pass through. However,
the airmass will be quite dry so it should remain dry. A slight
moderation in temperatures are expected but they will remain about
15 degrees below average.
A particularly cold air mass will swing into the Central Plains
Monday into Tuesday. This will result in the coldest temperatures we
have seen this fall with both Monday`s high temperatures and Tuesday
morning`s low temperatures possibly setting new records. Here is a
quick look at just some of those threatened temperature records.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1145 AM CST SAT NOV 15 2014
Band of heavier snow will affect far northwest and north central MO
this afternoon with MVFR visibilities and cigs. The higher
accumulating snows will miss the Kansas City terminals and graze KSTJ.
For the terminals, after the initial light snow with MVFR
visibilities/cigs moves through very early this afternoon expect
cigs to improve into the low end VFR category for the rest of this
afternoon and evening. Intermittent light snow or flurries expected through
the night with only minor additional accumulations. Weak frontal
passage from northwest to southeast starting in the pre-dawn hours.
Could see several hours of MVFR cigs after frontal passage with these
clouds clearing to the southeast by mid morning.
&&
.CLIMATE...
Issued at 418 PM CST SAT NOV 15 2014
Monday
November 17th Current Record Low Forecast High Monday
Record Low Highs High Afternoon
--------------------------------------------------------------------
Kansas City 24 in 1891 22
St. Joseph 26 in 1951 22
Tuesday
November 18th Current Record Low Forecast Low Tuesday
Record Lows Morning
--------------------------------------------------------------------
Kansas City 14 in 1903 7
St. Joseph 16 in 1989 5
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...WINTER WEATHER ADVISORY until Midnight CST tonight FOR
MOZ001>003-011.
&&
$$
UPDATE...MJ
DISCUSSION...MJ
AVIATION...MJ
CLIMATE...Cutter
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
351 PM CST Sat Nov 15 2014
.SHORT TERM: (Through Late Tonight)
Issued at 347 PM CST Sat Nov 15 2014
Shortwave exiting the eastern Plains into the Mississippi Valley is
producing a little bit of light snow and flurry activity across the
CWFA today. Looks like the best snowfall has moved north of our
CWFA across extreme northeast Missouri and southeast Iowa into west
central Illinois. The broad scale mid level lift associated with
the shortwave is lifting quickly northeast according to the RAP and
NAM. Will likely see a little bit of lingering snowfall up there
this evening, but any accumulations this evening should be well
under an inch.
Further south, HRRR and RAP have been very insistent that there will
be a frontogenetical band of snow this evening somewhere between
I-44 and I-70. The band will move northeast affecting parts of the
STL metro area with some light snow. Simulated reflectivity off the
4km NCEP and NSSL WRF models also show this, and the operational NAM
and GFS bear this out with a few hundredths of QPF. Latest radar
mosaic shows a band of snow developing west central Missouri
now...so this looks likely to happen. Have a band of likely PoPs
this evening in to account for this snow, stretching across central
Missouri into southwest Illinois to account for this.
Carney
.LONG TERM: (Sunday through Next Saturday)
Issued at 347 PM CST Sat Nov 15 2014
(Sunday thru Tuesday)
This period will continue to feature much below normal temps and
another shot at accumulating snow. Models have come into better
agreement with the system for Sunday/Sunday night. All guidance has
shifted the forcing and subsequently the precip shield further
north. Timing should be similar to today`s event. Precip is
expected to begin across cntrl and SE MO around noon and then spread
east thru the rest of the CWA during the aftn and then clear from W
to E during the evng and be but a memory by midnight. The main
p-type should be snow with temps aloft plenty cold enough to support
ice crystal formation but...air temps above freezing at the
beginning of the event may cause a rain/snow mix at the onset of the
precip. I think the mix won`t last long as temps should wet bulb
shortly after the precip begins. This will likely lead to a
non-diurnal temp trend as temps fall across the sthrn CWA as the
precip progresses east. Accum rates may be limited early on in the
event for a variety of reasons beyond the warm air temps
including...ground temps will likely be above freezing, snowfall
rates may not be high enough and the aftn sun...even with the
diminished angle...will have an effect. Event total snowfall amounts
should be 1-2 inches along and south of I70. There may be a band of
slightly enhanced snowfall along the I44 corridor that may reach
upwards of 3 inches but not confident on band placement to include
in the fcst attm. The system quickly lifts east after midnight.
Monday looks like a raw day with potentially steady or slowly
falling temps and a stiff NW wind as a 1030mb sfc high builds in.
850 temps fall from the negative single digits at 6Z Monday to the
negative mid teens to near -20 by Monday evening. There is also an
impressive short wave dropping down in the NW flow on Monday that
should instigate at least occnl flurries with the possibility of
actual snow showers...as was the case this past Thursday. Models
hint at patchy QPF which would equate to a few tenths of an inch of
snow...but will let later shifts asses that threat as it is still 2
days away. Tuesday should be the last truly cold day as the sfc
ridge passes to the south.
(Tuesday night thru Friday)
The upper flow flattens thru the end of the week which will allow
for a moderating trend. Winds will swing around to the south on the
backside of the high Tuesday night. 850 temps near 0 and a Srly wind
will boost temps to the upper 30s north to the upper 40s south
on Wednesday. The next short waves pushes a cold front thru late in
the day on Wednesday causing temps on Thursday and Friday to be a
touch cooler. This front appears to be dry at this time. Models
guidance diverges after this feature with the GFS building a strong
sfc ridge into the Midwest for the end of the week while the ECMWF
has another short wave and an attendant weak sfc low that tracks
across sthrn MO/IL Thursday/Thursday night.
Both models suggest another storm system for either the wknd and/or
early next week as the next main short wave approaches in the mean
flow.
2%
&&
.AVIATION: (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1204 PM CST Sat Nov 15 2014
Upper level disturbance moving out of eastern Kansas into Missouri
is producing snow over northern/northwestern portions of the
state. Some trailing precipitation to the south will overspread
the area this afternoon, but due to very dry low levels, it will
take a while to make it to the ground. Think best chances of snow
this afternoon will be across northern portions of the CWFA in
northeast Missouri and west central Illinois, tho some light snow
is also likely further south. Another band of snow will likely
form between I-44 and I-70 across Missouri and move northeast this
evening impacting east central Missouri into southwest Illinois.
VFR flight conditions should prevail outside of some of the
heavier snow showers this afternoon and the bands across northern
Missouri this afternoon, and the second band in east central
Missouri and southwest Illinois. Flight conditions could drop to
IFR in these areas, but MVFR vsbys/ceilings are most likely. After
the southern band moves out this evening, VFR flight conditions
are expected through Sunday morning.
Specifics for KSTL:
Expect VFR flight conditions to prevail for most of the afternoon.
Precipitation west of the terminal associated with an upper level
disturbance will most likely evaporate before hitting the ground,
but another band of snow is expected to develop between I-44 and
I-70 across Missouri and move northeast this evening impacting east
central Missouri into southwest Illinois. The exact position of
the band will determine how heavy the snow will get at Lambert,
but the band should be fairly narrow and short-lived. While there
is a chance for IFR conditions with the band, think the most
likely impact will be MVFR visibility for a short period this
evening. VFR flight conditions are expected to prevail after the
band clears the region by mid-evening. There is another chance of
snow Sunday afternoon...but have left mention out for now to focus
on the short-range forecast.
Carney
&&
.CLIMATE:
Issued at 748 PM CST Thu Nov 13 2014
The following are record low maximums and record low minimums for
each of the next 5 days, which corresponds to the expected length
of the current cold spell and record snowfall for St. Louis and
Columbia for Saturday and Sunday when the area is expecting the
first widespread accumulating snowfall of the season.
Date: 11/15 11/16 11/17 11/18
St. Louis
Low High: 29/1940 29/1997 17/1880 25/1880
Low: 11/1940 13/1959 6/1959 14/1932
Snowfall: 0.1/1997 1.0/1951
Columbia
Low High: 28/1940 30/1932 23/1959 27/1903
Low: 6/1940 8/1959 4/1959 8/1891
Snowfall: 4.8/1932 0.1/1989
Quincy
Low High: 29/1940 28/1997 19/1959 24/1903
Low: 7/1940 4/1959 3/1959 7/1903
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
337 PM CST SAT NOV 15 2014
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 331 PM CST SAT NOV 15 2014
ENDING SNOW TONIGHT...THEN COLD TEMPERATURES THE NEXT FEW DAYS...ARE
THE PRIMARY FORECAST CONCERNS.
FIRST ROUND OF SNOW TIED TO SOUTHERN SHORTWAVE/WARM ADVECTION
PATTERN MOVED EAST/NORTHEAST OF THE CWA BY EARLY AFTERNOON. THIS
AREA DROPPED AN INCH OR TWO OF SNOW ACROSS THE SOUTHERN HALF OF
THE CWA. ANOTHER AREA OF SNOW WAS ENTERED THE WESTERN PART OF
NORTHEAST NEBRASKA EARLY IN THE AFTERNOON. THIS WAS TIED TO
STRONGER UPPER LOW/TROUGH SWINGING THROUGH WESTERN SOUTH DAKOTA.
75KT MID LEVEL JET WAS ROUNDING BASE OF THIS FEATURE...INCREASING
LIFT IN NORTHEAST WHERE SECOND ROUND OF SNOW WAS FALLING THIS
AFTERNOON. CHARACTER OF RADAR RETURNS SUGGEST THIS AREA WILL
PRODUCE LIGHT SNOW FOR THE MOST PART...WITH A FEW ROUNDS OF
MODERATE SNOW FROM TIME TO TIME. PROGRESSIVE NATURE ALSO SUGGESTS
MESOSCALE MODEL FORECASTS FROM HRRR AND RAP IN SHOWING SNOW
AFFECTING MAINLY THE NORTHERN HALF OF THE CWA AND WINDING DOWN BY
MIDNIGHT STILL LOOKS GOOD. ADDITIONAL AMOUNTS OF 1 TO 2 INCHES ARE
POSSIBLE IN THE NORTHERN TWO-THIRDS OF THE CWA TAPERING TO LESS
THAN AN INCH TOWARD THE KANSAS BORDER.
BACK EDGE OF SNOW WILL ALSO COINCIDE WITH COLD FRONT SWEEPING ACROSS
THE PLAINS. FRONT WILL PASS NORFOLK BY 9 PM AND BE APPROACHING OMAHA
BY MIDNIGHT. GUSTY NORTHWEST WINDS OF 15 TO 25 MPH SHOULD
FOLLOW...CAUSING A LITTLE BLOWING AND DRIFTING OF SNOW OVERNIGHT
BEFORE WINDS BEGIN TO SUBSIDE SOME ON SUNDAY. CLEARING SKIES AFTER
MIDNIGHT...COLD AIRMASS AND FRESH SNOW COVER WILL LEAD TO COLD
TEMPERATURES BY MORNING...WITH WINDS ONLY THING KEEPING LOWS FROM
BOTTOMING OUT. SINGLE DIGITS ARE FORECAST MOST EVERYWHERE.
SUNDAY WILL BRING SUNSHINE AND SOUTHWEST FLOW AHEAD OF A REINFORCING
COLD FRONT SLATED TO ARRIVE INTO NORTHEAST NEBRASKA IN THE
AFTERNOON...THEN THROUGH THE REST OF THE AREA DURING THE EVENING.
SNOW COVER WILL KEEP TEMPS FROM REACHING MAXIMUM POTENTIAL SUNDAY
AFTERNOON...WITH LOWER 20S EXPECTED MOST AREAS. MORE GUSTY NORTHWEST
WINDS WILL ACCOMPANY COLD FRONT AND SHOULD CONTINUE ALL NIGHT.
EXTREMELY COLD AIRMASS FOLLOWS THE FRONT WITH MODELS SHOWING -20
850 TEMPERATURES INTO OUR NORTHERN CWA BY 12Z MONDAY. THIS WILL
TRANSLATE TO LOWS AGAIN IN THE SINGLE DIGITS WITH HIGHS REBOUNDING
ONLY BACK INTO THE TEENS MONDAY AFTERNOON. WIND CHILLS MONDAY
MORNING WILL LIKELY FALL TO 15 BELOW OR COLDER FOR MUCH OF THE
NORTHERN HALF OF THE CWA.
DECREASING WINDS AND CLEARING SKIES SUGGEST TUESDAY MORNING MAY BE
THE COLDEST OF THIS RECENT COLD SPELL. LOWS NEAR ZERO ARE LIKELY
ACROSS ALL OF EASTERN NEBRASKA AND SOUTHWEST IOWA...WITH SUB-ZERO
TEMPS NEARLY A CERTAINTY IN OUR NORTH. SOUTHWEST FLOW RETURNS FOR
TUESDAY...HELPING TO WARM TEMPS BACK INTO THE MID 20S IN THE
AFTERNOON.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 331 PM CST SAT NOV 15 2014
SLOWLY MODERATING TEMPERATURES APPEAR TO BE THE MAIN STORY IN THE
LONGER TERM PERIOD.
ANOTHER SHORTWAVE IS SHOWN BY GFS/ECMWF SLAMMING THROUGH MINNESOTA
AND IOWA TUESDAY NIGHT...BRINGING ANOTHER SHOT OF COLDER AIR INTO
THE PLAINS THROUGH WEDNESDAY. HOWEVER THIS WILL NOT BE NEARLY AS
COLD AS EARLIER IN THE WEEK WITH HIGHS WEDNESDAY INTO THE 20S AND
LOWER 30S. MID LEVEL HEIGHTS BEGIN A SLOW RISE FOR THE REST OF THE
WEEK AS FLOW BECOMES MORE ZONAL BEHIND TUESDAY NIGHT SHORTWAVE.
ANOTHER SHOT OF SOMEWHAT COOLER AIR IS EXPECTED THURSDAY...BUT THAT
LOOKS SHORT-LIVED. HAVE HIGHS REBOUNDING BACK INTO THE 30S FRIDAY
AND SATURDAY. OTHERWISE A DRY FORECAST REMAINS INTACT.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1209 PM CST SAT NOV 15 2014
MAIN BAND OF MODERATE TO HEAVY SNOW ABOUT TO MOVE ACROSS KOMA AT
THE START OF THE PERIOD. ONCE THIS AREA MOVES TO THE EAST EXPECT
PRIMARILY MVFR CIGS AND VSBY AT ALL THREE SITES WITH OCCASIONAL
IFR CONDITIONS THROUGH ABOUT 02Z IN ADVANCE AND JUST BEHIND THE
COLD FRONT MOVING INTO CENTRAL NEBRASKA AT 18Z. VFR CONDITIONS ARE
EXPECTED TO DEVELOP AFTER 12Z AS FRONT MOVES FURTHER EAST AND HIGH
PRESSURE BUILDS INTO THE AREA AHEAD OF NEXT COLD FRONT. THIS SECOND
COLD FRONT WILL BE MOVING INTO THE AREA JUST AFTER THE END OF
THE FORECAST PERIOD.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NEZ011-
012-015>018-030>034-042>045-050>053-065>068-078.
IA...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR IAZ043-
055-056-069-079-080-090-091.
&&
$$
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
334 PM EST SAT NOV 15 2014
.SYNOPSIS...HIGH PRESSURE CENTERED OVER THE REGION THIS AFTERNOON
WILL GRADUALLY SHIFT OFFSHORE TONIGHT AND SUNDAY. A DEVELOPING LOW
PRESSURE SYSTEM ATTENDANT AN AMPLIFYING UPPER LEVEL TROUGH WILL
INTENSIFY IN VICINITY OF THE LOUISIANA GULF COAST ON SUNDAY...THEN
TRACK NORTHEAST ALONG THE SPINE OF THE APPALACHIANS SUNDAY NIGHT
INTO MONDAY. AN ASSOCIATED COLD FRONT WILL SWEEP EASTWARD THROUGH
THE CAROLINAS MONDAY AFTERNOON AND EVENING.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM SATURDAY...
TODAY: MODIFIED ARCTIC HIGH PRESSURE CENTERED OVER THE REGION WILL
ENSURE THAT DRY CONDITIONS AND LIGHT/VARIABLE WINDS PREVAIL THROUGH
TONIGHT. THE LOW-LEVEL CORE OF THE MODIFIED ARCTIC AIRMASS WAS
ANALYZED DIRECTLY OVER CENTRAL NC AND EASTERN VA THIS AFTERNOON
(18Z)...CHARACTERIZED BY 925 MB TEMPS IN VICINITY OF -2C. PWAT
VALUES BOTTOMED OUT AT A `FINGER-CRACKING` 0.14 INCHES ON THE GSO
RAOB 00Z YESTERDAY. 18Z MESOANALYSIS AND RAP DATA INDICATE MID/UPPER
LEVEL MOISTURE HAS STEADILY INCREASED SINCE 00Z...THOUGH LITTLE
EVIDENCE THEREOF (I.E. CIRRUS) CAN BE IDENTIFIED VIA SATELLITE
IMAGERY. GIVEN CLEAR SKIES AND MARGINAL LOW-LEVEL MODIFICATION IN
COMPARISON TO YESTERDAY...EXPECT HIGHS SIMILAR ALBEIT SLIGHTLY WARMER
THAN YESTERDAY...IN THE LOWER/MID 40S.
TONIGHT: MODIFIED ARCTIC HIGH PRESSURE CENTERED OVER THE MID-
ATLANTIC THIS EVENING WILL SHIFT OFFSHORE THE MID-ATLANTIC COAST
LATE TONIGHT...IN ADVANCE OF SHORTWAVE ENERGY TRACKING EASTWARD FROM
THE DAKOTAS TO THE UPPER GREAT LAKES. MEANWHILE...UPSTREAM PRECIP IS
EXPECTED TO BLOSSOM ACROSS THE LOWER MS RIVER VALLEY AFTER MIDNIGHT
AS SHORTWAVE ENERGY DIGS SSE FROM THE PACIFIC NW TO THE COLORADO
FRONT RANGE. ASIDE FROM AN INCREASING LIKELIHOOD OF CIRRUS ADVECTING
INTO THE REGION VIA WSW FLOW ALOFT...FAVORABLE RADIATIONAL COOLING
CONDITIONS WILL OTHERWISE PREVAIL. DUE TO AIRMASS MODIFICATION
ASSOC/W THE ONSET OF A LIGHT SOUTHERLY/SW RETURN FLOW...ANTICIPATE
LOWS A FEW DEGREES WARMER THAN THIS MORNING...IN THE MID TO UPPER
20S. -VINCENT
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 315 PM SATURDAY...
SUN/SUN NIGHT: CHALLENGING TEMPERATURE AND PRECIP FORECAST. THE
ONSET OF WARM ADVECTION...I.E. SOUTHERLY RETURN FLOW EMANATING FROM
THE ATLANTIC /GULF STREAM/...WILL RESULT IN INCREASING CLOUD COVER
AND THE DEVELOPMENT OF A HYBRID OR IN-SITU COLD AIR DAMMING WEDGE.
ELEVATED SHOWER ACTIVITY WILL BE POSSIBLE SUNDAY EVE/NIGHT AS LOW-
LEVEL WARM ADVECTION FURTHER STRENGTHENS ATOP THE SHALLOW COLD AIR
DAMMING WEDGE IN ADVANCE OF A WARM FRONT LIFTING NORTHWARD THROUGH
CENTRAL/EASTERN NC. GIVEN THE EXPECTATION OF BROKEN/OVERCAST
CEILINGS AT LOWER (STRATUS) AND UPPER (CIRRUS) LEVELS...EVAP COOLING
ASSOCIATED WITH AN INITIALLY DRY SURFACE AIRMASS ALONG WITH VIRGA
AND AN INCREASING POTENTIAL FOR ELEVATED SHOWERS...EXPECT CHILLY
AFTERNOON TEMPERATURES RANGING FROM THE UPPER 30S TO MID 40S (NW) TO
MID 40S/LOWER 50S IN THE SE COASTAL PLAIN. EXPECT TEMPERATURES TO
RISE OVERNIGHT FROM SOUTH TO NORTH AS THE LOW-LEVELS SATURATE AND A
WARM FRONT LIFTS NORTHWARD THROUGH CENTRAL/EASTERN NC. TEMPS IN THE
TRIAD MAY HOLD STEADY FOR MUCH OF THE NIGHT...THOUGH A SLOW RISE
STILL APPEARS LIKELY BY SUNRISE. -VINCENT
MONDAY THROUGH MONDAY NIGHT...UPPER TROF ROTATING ACROSS THE UPPER
MIDWEST INTO THE GREAT LAKES WILL PUSH THE STRONG COLD FRONT EAST
ACROSS THE AREA. AMPLITUDE OF THE SYSTEM WILL PROVIDE A DEEP
SOUTHWEST TAP INTO THE GULF AHEAD OF THE FRONT...WITH A PLUME OF
PRECIPITABLE WATER OF 1.5 INCHES EDGING INTO CENTRAL AND EASTERN
NORTH CAROLINA BY AFTERNOON COURTESY OF A 50+ KNOT LOW LEVEL JET AT
H850 STRAIGHT OFF THE GULF. TIMING DISCREPANCIES ARE MINOR
CONCERNING SENSIBLE WEATHER AND WILL MAINTAIN OUR ONGOING
CATEGORICAL POPS IN THE WEST IN THE MORNING PROGRESSING EAST TO THE
I-95 CORRIDOR DURING THE AFTERNOON. SOUTHERLY WINDS AT 10-15 MPH
GUSTING TO 20 WILL VEER SOUTHWEST TO WEST DURING THE AFTERNOON AND
NORTHWEST OVERNIGHT.
HIGHS IN THE EAST WILL HAVE AMPLE TIME TO REACH NEAR 70 PRIOR TO THE
FRONT WHICH PROGS TO A COUPLE OF HUNDRED JOULES OF CAPE. VERTICAL
ALIGNMENT OF THE DEPARTING 150KT UPPER JETS DIFFLUENCE AND
PERTURBATIONS IN THE MID LEVEL FLOW WOULD AID CONVECTIVE DEVELOPMENT
AND WILL EXPAND MENTION OF THUNDER WEST ACROSS THE TRIANGLE AND
SANDHILLS. TEMPERATURES IN THE NORTHWEST ARE A LITTLE MORE UNCERTAIN
DUE TO POTENTIAL FOR IN-SITU LINGERING COOL AIR DUE TO EVAPORATIVE
COOLING SUNDAY NIGHT. THIS WOULD BLOCK THE TRANSITION TO A MORE
PLEASANT SOUTHERLY SURFACE FLOW AND HIGHS WOULD STRUGGLE TO REACH
MID 50S.
THE FRONT WILL BE MOVING SMARTLY ALONG...WITH SHOWERS ENDING AND
CLEARING COMMENCING TOWARDS SUNSET IN THE WEST TO AROUND MIDNIGHT IN
THE EAST. TEMPS WILL PLUMMET AS COLD AIR RUSHES IN AND THICKNESSES
CRASH OVERNIGHT...MONDAY NIGHTS MINS LOOK TO FALL BELOW FREEZING
OVER THE PIEDMONT...WITH MID 30S IN THE EASTERN THIRD OF THE AREA.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 300 PM SATURDAY...
A COLD STRETCH IS ON TAP BEHIND THE FRONT AS POLAR AIR PAYS THE AREA
A VISIT TUESDAY AND WEDNESDAY. THE INITIAL SURGE WILL BE BRISK AND
RAW ON TUESDAY...FEATURING NORTHWEST WIND GUSTING TO 20 MPH AND
THICKNESSES BARELY INDICATIVE OF MID 30S OVER THE NORTHWEST TO LOWER
40S SOUTHEAST. SURFACE HIGH SETTLING OVER THE AREA AND LOOSENING
PRESSURE GRADIENT WILL BE IDEAL FOR RADIATIONAL COOLING AND MINS
WILL BE COLDEST WEDNESDAY MORNING...WITH MOST AREAS WITHIN A COUPLE
OF DEGREES OF 20. SLIGHT DEAMPLIFICATION OF THE TROF AND ANOTHER DAY
OF STRONG INSOLATION WILL PROVIDE SOME VERY MODEST WARMING ON
WEDNESDAY...WITH HIGHS FROM 40 TO 45.
FORECAST FOR LATE WEEK IS MORE UNCERTAIN AS THERE IS MODEL
UNCERTAINTY IN THE SUBSEQUENT EVOLUTION OF THE UPPER TROF AND
STRONGER INDICATIONS OF A SURFACE SYSTEM DEVELOPING AND SKIRTING THE
AREA ON FRIDAY IN THE ECMWF. REGARDLESS...TEMPS WILL MODERATE IN THE
THURSDAY THROUGH SATURDAY TIME FRAME AS THE TROF DEAMPLIFIES AND
HIGHS EACH DAY LOOK TO BE IN THE LOW TO MID 50S...MAYBE A LITTLE
WARMER ON THE WEEKEND AS WE SIT UNDER A STRONG HIGH AND TRANSITION
BRIEFLY TO A LOW AMPLITUDE UPPER RIDGE. AT THIS POINT AM THINKING
ONLY HIGH CLOUDINESS IN THE FASTER FLATTER FLOW AND WILL HAVE ONLY
SLIGHT CHANCE POPS FOR THE FRIDAY NIGHT INTO SATURDAY TIME FRAME.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 100 PM SATURDAY...
24-HR TAF PERIOD: VFR CONDITIONS AND LIGHT WINDS WILL PREVAIL
THROUGH TONIGHT AT ALL TERMINALS AS HIGH PRESSURE CENTERED OVER THE
REGION GRADUALLY BEGINS TO SHIFT OFFSHORE. SUB-VFR CEILINGS WILL BE
POSSIBLE AT ALL TERMINALS BY THE END OF THE TAF PERIOD (12-18Z SUN)
IN ASSOCIATION WITH THE ONSET OF WARM ADVECTION AS THE SFC HIGH
MOVES FURTHER OFFSHORE AND A WARM/MOIST AIRMASS ADVECTS INTO THE
CAROLINAS FROM THE ATLANTIC.
LOOKING AHEAD: AN EXTENDED PERIOD OF ADVERSE AVIATION CONDITIONS IS
EXPECTED SUNDAY AFT/EVE INTO SUN NIGHT IN ASSOC/W WARM ADVECTION
ATOP A SHALLOW COLD AIR DAMMING WEDGE IN ADVANCE OF A POTENT COLD
FRONT APPROACHING THE MOUNTAINS FROM THE WEST. THE COLD FRONT WILL
SWEEP EASTWARD THROUGH THE REGION LATE MONDAY AFTERNOON. BREEZY
NORTHWEST WINDS WILL OCCUR IN THE WAKE OF THE FRONT MONDAY NIGHT
INTO TUESDAY AS ANOTHER ARCTIC HIGH BUILDS INTO THE REGION FROM THE
WEST. -VINCENT
&&
THE FOLLOWING ARE RECORD TEMPERATURES THAT WILL BE CHALLENGED
THROUGH THE FORECAST PERIOD:
RECORD LOW:
GSO RDU FAY
WED 11/19 - 20 IN 1951 21 IN 1903 21 IN 1959
THU 11/20 - 12 IN 1951 19 IN 1951 20 IN 1951
RECORD LOW MAX:
GSO RDU FAY
TUE 11/18 - 37 IN 1924 35 IN 1924 46 IN 2008
WED 11/19 - 34 IN 1951 36 IN 1951 41 IN 2000
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...VINCENT
LONG TERM...MONEYPENNY
AVIATION...VINCENT
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
240 AM EST SAT NOV 15 2014
.SYNOPSIS...HIGH PRESSURE WILL SETTLE OVER THE REGION ON SATURDAY...
THEN SHIFT OFFSHORE SUNDAY AND SUNDAY NIGHT AS A COLD FRONT
APPROACHES THE MOUNTAINS FROM THE WEST. A COLD FRONT WILL SURGE
EASTWARD THROUGH THE CAROLINAS MONDAY EVENING.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 230 AM SATURDAY...
TODAY AND TONIGHT: SURFACE HIGH PRESSURE WILL CENTER OVER NORTH
CAROLINA AND VIRGINIA ON SATURDAY AS MID-LEVEL FLOW BECOMES ZONAL OR
SLIGHTLY SOUTHWESTERLY. THAT MEANS THICKNESS VALUES WILL BEGIN TO
RISE AND TEMPERATURES WILL BOTTOM OUT WITH THE MINIMUMS SATURDAY
MORNING...IN THE LOW TO MID 20S. WITH NO DISTURBANCES IN THE UPPER
LEVEL VORTICITY FIELD AND HIGH PRESSURE IN CONTROL...SATURDAY SHOULD
BE A MOSTLY CLEAR DAY WITH MINIMAL WIND. THIS WILL GIVE CONDITIONS
FOR INSOLATION BUT WITH THE COLD AIRMASS IN PLACE AND THICKNESS
VALUES ONLY JUST APPROACHING 1300 N BY THE SATURDAY AFTERNOON...ONLY
EXPECT HIGHS TO TOP OUT IN THE MID 40S ACROSS THE AREA. SLIGHT WARM
AIR ADVECTION WILL MODERATE THICKNESS SATURDAY NIGHT BY TEN METERS
OR SO...DRIVING A 3-5 DEGREE IMPROVEMENT IN LOW TEMPERATURES SUNDAY
MORNING.
SUNDAY: HIGH PRESSURE BEGINS TO SHIFT EASTWARD AND CENTRAL NC WILL
BEGIN TO FEEL SOME RETURN FLOW. THIS WILL HELP MODERATE TEMPERATURES
ON SUNDAY INTO THE LOWER 50S...STILL ABOUT 10 DEGREES BELOW NORMAL
FOR THIS TIME OF YEAR. A VORTICITY MAXIMUM WILL APPROACH FROM THE
SOUTH WHICH WILL CAUSE THE AREA TO OVERSPREAD WITH SOME 850 MB
CLOUDINESS BY SUNDAY AFTERNOON. MOST OF THE AREA SHOULD REMAIN DRY
HOWEVER AS PRECIPIATION ASSOCIATED WITH THE DEVELOPING TROUGH
REMAINS TO THE SOUTHEAST AND THE APPROACHING FRONTAL SYSTEM REMAINS
WEST OF THE AREA...DRAPED ACROSS THE DEEP SOUTH. THE CAVEAT TO THIS
IS THAT THE POSITION OF THE SURFACE HIGH AND NEWLY FORMING TROUGH
WILL HELP SET UP AN IN-SITU DAMMING SITUATION WITH A COASTAL FRONT
THAT COULD PROVIDE THE MOISTURE FOR SOME LIGHT OVERRUNNING
PRECIPITATION DRIVEN BY ISENTROPIC LIFT.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 235 AM SATURDAY...
SUNDAY NIGHT: HOW LONG THE IN-SITU DAMMING SITUATION HANGS AROUND
REMAINS TO BE SEEN AS THE VERY DEEP UPPER LEVEL TROUGH OVER THE
CENTRAL CONUS IS QUITE AGGRESSIVE WITH FORCING THE FRONTAL SYSTEM
OVER THE APPALACHIANS INTO THE AREA AND BLOWING OUT THE WEDGE FRONT.
WHETHER OR NOT THE DAMMING STICKS AROUND OR THE FRONT APPROACHES
FROM THE WEST...THE UPSHOT WILL BE THE SAME...AN INCREASE IN POPS
FOR SUNDAY NIGHT INTO EARLY MONDAY MORNING WITH THE GREATEST CHANCES
IN THE NORTHWEST BUT QPF VALUES REMAINING UNDER A QUARTER OF AN INCH
THROUGH 12Z MONDAY. INCREASED WARM AIR ADVECTION WILL HELP THICKNESS
VALUES REACH 1350 M BY DAYBREAK ON MONDAY AND THUS LOWS WILL
MODERATE SIGNIFICANTLY..INTO THE LOW TO MID 40S. -ELLIS
FOR MON/MON NIGHT: MONDAY WILL START WITH THE WARM FRONT SW-TO-NE
THROUGH CENTRAL NC MOVING TO THE NW... AS THE STRONG COLD FRONT
APPROACHES FROM THE EAST. RAIN IS EXPECTED TO CONTINUE INTO
MONDAY... WITH HIGHEST POPS IN THE NW HALF OF CENTRAL NC IN THE
MORNING... SPREADING EAST THROUGH THE AFTERNOON. STRONG LOW LEVEL
MASS FLUX CONFLUENCE COUPLED WITH VIGOROUS UPPER DIVERGENCE WILL
CONTINUE TO FUEL WIDESPREAD PRECIP... WITH ADDITIONAL FORCING FOR
ASCENT PROVIDED BY POCKETS OF MID LEVEL VORTICITY (DIFFICULT TO
PINPOINT AT THIS RANGE) THAT WILL TRACK TO THE NE WITHIN THE FAST
MID LEVEL SWRLY FLOW... PART OF THE STRONG BROAD TROUGH COVERING
NEARLY THE ENTIRE CONUS. BASED ON THIS EXPECTED DEEP LIFT AND
ABUNDANT MOISTURE (PW VALUES OVER 1.5 INCHES NOW OVER THE SOURCE
REGION IN THE BAY OF CAMPECHE WILL SURGE NE INTO NC BY MON...
EQUATING TO PW OF 2 STANDARD DEVIATIONS ABOVE NORMAL)... WILL BUMP
UP POPS TO CATEGORICAL... MAINLY WEST HALF MON MORNING AND EXPANDING
EAST IN THE AFTERNOON BEFORE SLOWLY EXITING IN THE EVENING. THE
NAM/GFS/ECMWF ALL DIFFER SLIGHTLY WITH THE PLACEMENT AND STRENGTH OF
SURFACE LOWS TRACKING ALONG THE INCOMING COLD FRONT... WITH THE
GFS/ECMWF SHOWING STRONGER LOWS AND A SLIGHTLY FASTER FRONTAL
PASSAGE THROUGH CENTRAL NC MON AFTERNOON/EVENING AS COMPARED TO THE
NAM... BUT OVERALL TIMING IS IN FAIRLY DECENT AGREEMENT. BOTH THE
NAM AND GFS DEPICT LOW BUT NON-ZERO MUCAPE VALUES IN THE EAST MON
AFTERNOON INTO EARLY EVENING (100-250 J/KG ON THE GFS AND 250-750
J/KG ON THE NAM) WITH STRONG DEEP LAYER SHEAR OF 60-90 KTS... AND
WHILE MID LEVEL LAPSE RATES ARE JUST MARGINAL AT 5.5-6.0 C/KM... THE
MOISTURE ALOFT AND ASCENT ARE SUFFICIENT TO MENTION ISOLATED THUNDER
IN THE ERN CWA LATE MON. TEMP FORECAST FOR MON IS A CHALLENGE...
GIVEN THE HIGH POTENTIAL FOR A WEDGE REGIME TO HOLD IN THE NW
PIEDMONT DESPITE A STRONG SSW LOW LEVEL FLOW PRECEDING THE FRONT.
THE NAM REMAINS THE MOST SUPPORTIVE OF A LINGER WEDGE... IN LINE
WITH THE 12Z/14TH ECMWF... HOWEVER THE NEW ECMWF IS CLOSER TO THE
GFS WITH A STRONGER ALONG-FRONT SURFACE LOW AND RESULTING PREFRONTAL
DISSOLUTION OF THE WEDGE REGIME. WITH THE LACK OF MODEL CONSENSUS ON
THIS AND BASED ON PAST EXPERIENCE... WILL STICK WITH LINGERING
COLDER AND MORE STABLE AIR OVER THE NW MON... BUT STAY TUNED... AS
JUST A QUICK JUMP OF THE WARM FRONT MORE TO THE NW WILL YIELD MUCH
HIGHER TEMPS. WILL HAVE HIGHS RANGING FROM AROUND 50 NW TO AROUND 70
SE... WITH PERIODICALLY GUSTY SW WINDS... ALTHOUGH THE MOIST
ADIABATIC LOW LEVEL PROFILE COULD LIMIT MIXING OF THE STRONGEST
WINDS DOWN TO THE SURFACE. EXPECT THE COLD FRONT TO MOVE QUICKLY
EAST AND OFF THE COAST MON NIGHT... WITH MUCH COLDER AIR SURGING IN
FROM THE NW... AND GRADUAL CLEARING OVERNIGHT. WE`LL HANG ONTO THE
MIXED LAYER UP THROUGH ABOUT 900 MB OVERNIGHT... AND NW WINDS BEING
THE FRONT WILL BE QUITE BRISK WITH OCCASIONAL GUSTS OVER 20 MPH
POSSIBLE. THE POLAR CHARACTER OF THE INCOMING AIR MASS WITH LITTLE
IMPEDIMENT TO ITS ARRIVAL SUPPORTS LOWS JUST A TAD LOWER THAN
PREVIOUS LOWS... FROM 26 WEST TO 38 SOUTHEAST. -GIH
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 235 AM SATURDAY...
WITH THE POLAR FLOODGATES WIDE OPEN... THE COLDEST AIR OF THIS
STRETCH WILL BE UPON US TUE... MAKING THIS THE CHILLIEST DAY AS
FORECAST THICKNESSES BOTTOM OUT BELOW 1275 M OVER MOST OF CENTRAL
NC. THESE VALUES ALONG WITH FORECAST SOUNDINGS INDICATE A STRUGGLE
TO GET OUT OF THE MID 30S OVER THE NW PIEDMONT... DESPITE PLENTIFUL
SUNSHINE. HAVE TRENDED TEMPS IN THIS DIRECTION... WITH HIGHS FROM 37
NW TO 44 SE. THE TROUGH LIFTS NE AND WEAKENS A BIT WED/THU AS THE
SURFACE HIGH MODIFIES WHILE SLIDING ACROSS THE SOUTHEAST STATES.
SHOULD SEE HIGHS BACK UP INTO THE LOW-MID 40S THU AND AROUND 50-55
THU... STILL WELL BELOW NORMAL. A FEW HIGH CLOUDS ARE LIKELY TO
RETURN LATE WED INTO WED NIGHT AS WEAK VORTICITY SHEARS ACROSS NC
WITHIN THE PERSISTENT CYCLONIC FLOW. DETAILS IN THE GFS/ECMWF START
TO GET VERY MURKY LATE THU INTO FRI AS LONGWAVE TROUGHING DIGS ANEW
THROUGH THE GREAT LAKES AND POTENTIALL DOWN INTO THE CENTRAL
PLAINS... WHICH WOULD MEAN THE SURFACE HIGH WOULD MOVE OFF THE COAST
WITH RESULTANT SW RETURN FLOW PUMPING MOISTURE INTO THE CAROLINA
AHEAD OF THE NEXT FRONT. WILL BRING IN SLIGHT CHANCE POPS ACROSS THE
WEST AND NORTH... STILL BELOW CLIMATOLOGY AND IN LINE WITH THE ECMWF
WHICH SHOWS PRECIP ENTERING WRN NC FRI. HIGHS FRI IN THE MID-UPPER
50S. EXPECT LOWS TUE NIGHT/WED MORNING IN THE TEENS TO LOW 20S...
SLOWLY WARMING THROUGH THE END OF THE WEEK TO AROUND FREEZING FRI
MORNING. -GIH
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 1235 AM SATURDAY...
24 HOUR TAF PERIOD: VERY HIGH CONFIDENCE OF VFR CONDITIONS
PERSISTING THROUGH THE TAF PERIOD AS HIGH PRESSURE BEGINS TO MOVE
OVERHEAD. THAT BEING SAID...THERE IS A THREAT TONIGHT FOR SOME LOW
LEVEL WIND SHEAR IN THE 500-1000 FT LAYER AT EASTERN SITES
(KRDU...KFAY...AND ESPECIALLY KRWI) WHERE WIND SPEEDS WILL GO FROM
RELATIVELY LIGHT AT 500 FT TO 25-30 KTS OR SO AT 1000 FT. THIS IS
BACKED UP BY WIND PROFILER DATA AT 530Z SHOWING 1 KT AT THE SURFACE
AND 33 KTS AT 900 FT. RAP FORECAST SOUNDINGS SHOW THIS ACTIVITY
CONTINUING UNTIL 13-14Z SATURDAY MORNING. OTHERWISE MOSTLY CLEAR
SKIES OVERNIGHT WITH LIGHT NORTHWESTERLY WINDS SHIFTING TO
NORTHEASTERLY DURING THE OVERNIGHT HOURS. FOR SATURDAY EXPECT WINDS
5-10 KTS OUT OF THE NORTHEAST THEN POSSIBLY SHIFTING TO A MORE
EASTERLY DIRECTION LATER IN THE AFTERNOON. BY 00Z OR SO SOME MID TO
HIGH LEVEL CLOUDS MAY START TO FILTER IN ABOVE 10 KFT.
LONG TERM: THE NEXT THREAT TO SUB-VFR CONDITIONS WILL COME ON MONDAY
AS A FRONTAL SYSTEM STARTS TO CROSS THE APPALACHIANS. HIGH PRESSURE
WILL THEN RETURN ON TUESDAY FOR THE REMAINDER OF THE WEEK.
&&
.CLIMATE...
THE FOLLOWING ARE RECORD TEMPERATURES THAT WILL BE CHALLENGED
THROUGH THE FORECAST PERIOD:
RECORD LOW:
GSO RDU FAY
SAT 11/15 - 20 IN 1969 21 IN 1969 22 IN 1942
WED 11/19 - 20 IN 1951 21 IN 1903 21 IN 1959
THU 11/20 - 12 IN 1951 19 IN 1951 20 IN 1951
RECORD LOW MAX:
GSO RDU FAY
TUE 11/18 - 37 IN 1924 35 IN 1924 46 IN 2008
WED 11/19 - 34 IN 1951 36 IN 1951 41 IN 2000
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...ELLIS
SHORT TERM...ELLIS/GIH
LONG TERM...GIH
AVIATION...ELLIS
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1236 AM EST SAT NOV 15 2014
.SYNOPSIS...HIGH PRESSURE WILL SETTLE OVER THE REGION ON SATURDAY...
THEN SHIFT OFFSHORE SUNDAY AND SUNDAY NIGHT AS A COLD FRONT
APPROACHES THE MOUNTAINS FROM THE WEST. THE COLD FRONT WILL SURGE
EASTWARD THROUGH THE CAROLINAS MONDAY EVENING.
&&
.NEAR TERM /TONIGHT/...
AS OF 730 PM FRIDAY...
MODIFIED ARCTIC HIGH PRESSURE BUILDING INTO THE REGION THIS EVENING
WILL SETTLE OVERHEAD TONIGHT. WITH CLEAR SKIES AND A COLD/DRY
AIRMASS IN PLACE...THE ONLY MITIGATING FACTOR W/REGARD TO THE
REALIZATION OF FULL RADIATIONAL COOLING WILL BE A LIGHT NW BREEZE
THROUGH 06-09Z. HOWEVER...PREVIOUS EXPERIENCE WOULD SUGGEST THAT
SEVERAL HRS OF CALM CONDITIONS PRIOR TO SUNRISE SHOULD BE SUFFICIENT
FOR LOWS IN THE LOW/MID 20S...PERHAPS UPPER TEENS IN A FEW
LOCATIONS WHERE WINDS REMAIN CALM FROM MIDNIGHT ONWARD. -VINCENT
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 250 PM FRIDAY...
SURFACE HIGH OVER THE FORECAST AREA WILL DRIFT EAST...THOUGH SURFACE
RIDGE AXIS WILL LINGER/EXTEND ACROSS THE REGION THROUGH EARLY
SUNDAY. WHILE THE LOWEST 10K OF THE ATMOSPHERE WILL BE TOO DRY TO
SUPPORT ANY CLOUDS...THE WLY FLOW ALOFT MAY ADVECT ENOUGH MOISTURE
TO CAUSE AREAS OF CIRRUS OVERHEAD LATE SATURDAY MORNING THROUGH
THE AFTERNOON. AT THIS TIME ANTICIPATE THE HIGH CLOUDS TO BE
THIN...SO THEY SHOULD NOT HAVE ANY IMPACTS ON TEMPS. IF CIRRUS
SHIELD THICKER/DENSER THAN CURRENTLY ANTICIPATED...THEN MAX
TEMPS MAY END UP BEING 3-4 DEGREES COOLER THAN FORECAST. THE DRY AIR
MASS WILL ALLOW TEMPS TO REBOUND FROM A FRIGID START. AFTERNOON
TEMPS SHOULD BE IN THE MID-UPPER 40S.
MODEL RH CROSS SECTIONS SUGGEST HIGH CLOUDS DEPARTING THE REGION
EARLY SATURDAY EVENING WITH MAINLY CLEAR SKIES FOR MOST OF THE NIGHT
UNTIL THE NEXT ROUND OF HIGH CLOUDS APPROACHES FROM THE WEST AROUND
DAYBREAK SUNDAY. THE MAINLY CLEAR SKIES AND CALM WINDS WILL AGAIN
ALLOW TEMPS TO FALL QUICKLY AFTER SUNSET. EXPECT MIN TEMPS SOLIDLY
IN THE MID-UPPER 20S.
SUNDAY...AS SURFACE HIGH RETREATS FARTHER AWAY FROM CENTRAL NC...THE
LOW LEVEL RETURN SLY FLOW WILL ADVECT MOISTURE OFF THE ATLANTIC INTO
THE SOUTHERN AND EASTERN SECTIONS OF CENTRAL NC. MODEL RH PLANE VIEW
PLOTS SUGGEST THE AIR MASS BETWEEN 925-850 MB ADEQUATELY MOIST TO
SUPPORT A DECK OF STRATOCU ACROSS THE SOUTHERN
PIEDMONT...SANDHILLS...AND SOUTHERN COASTAL PLAIN BY SUNDAY
AFTERNOON. OTHERWISE HIGH CLOUDS WILL THICKEN OVERHEAD ELSEWHERE IN
ADVANCE OF THE NEXT LOW PRESSURE SYSTEM. THERE MAY BE ENOUGH
ISENTROPIC UPGLIDE TO PERMIT THE DEVELOPMENT OF SPOTTY LIGHT RAIN
OVER THE FAR SOUTH-SE AND POSSIBLY THE FAR NW PRIOR TO SUNSET SUNDAY.
HIGH TEMPS SUNDAY WILL BE DICTATED TO THE EXTENT OF CLOUD COVER.
AIR MASS PROJECTED TO MODIFY WITH LOW LEVEL THICKNESSES IN THE MID
1330S. THESE VALUES STILL ABOUT 15M BELOW NORMAL...SUPPORTIVE OF MAX
TEMPS IN THE MID-UPPER 50S. SINCE EXPECTING THICKENING CLOUD
COVER...MAX TEMPS SHOULD TOP OUT IN THE LOW-MID 50S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
AS OF 305 PM FRIDAY...
FOR THE PERIOD SUNDAY NIGHT THROUGH MONDAY...A SERIES OF MID-LEVEL
SHORTWAVES ARE FORECAST TO MOVE THROUGH CENTRAL NORTH CAROLINA WITH
THE BEST LIFT FORECAST BY BOTH THE NAM AND GFS DURING THE DAY
MONDAY. THE NAM IS DRY FOR A LARGE PART OF SUNDAY NIGHT...WHICH IS
CLOSER TO WHAT THE 12Z ECMWF IS FORECASTING...WHILE THE GFS
SATURATES THE AIR MASS MUCH MORE QUICKLY SUNDAY NIGHT. BETTER 700MB
VORTICITY IS FORECAST MONDAY BY BOTH THE NAM AND THE GFS...AND THE
GREATER 850MB THETA-E AND K INDICES OCCUR THEN ALONG WITH THE
PASSAGE OF BETTER VORTICITY ON THE 1.5PVU SURFACE AS THE RIGHT
ENTRANCE REGION OF A 100KT 500MB JET APPROACHES LATE IN THE DAY.
FOR THIS FORECAST...EVEN THE DRIER NAM PROVIDES FOR LIKELY CHANCES
FOR RAIN IN THE TRIAD BY LATE SUNDAY NIGHT AND WILL BASICALLY
FORECAST LIKELY CHANCES THERE AND TOWARD ALBEMARLE AFTER MIDNIGHT
WITH CHANCES ELSEWHERE. FOR MONDAY...POPS WILL BE LIKELY WEST OF
INTERSTATE 95 FOR MUCH OF THE DAY...WITH LIKELY POPS ALONG AND EAST
OF INTERSTATE 95 AS THE 850MB THETA-E VALUES ARE MAXIMIZED IN
CENTRAL NORTH CAROLINA DURING THE AFTERNOON. AROUND 18Z...THE GFS
FORECASTS 850MB WINDS INCREASING TO AROUND 60KT IN THE COASTAL PLAIN
COINCIDENT WITH THE INCREASE IN 850MB THETA-E.
MUCAPE FROM 1000-500MB IS ONLY 100-200J/KG IN THE INTERSTATE 95
CORRIDOR MONDAY...AND NAM AND GFS BUFR SOUNDINGS SHOW LAPSE RATES
NEAR MOIST ADIABATIC. HOWEVER...THE 0-3KM SHEAR IS AROUND 50KT...
AND 0-3KM HELICITY IS FORECAST TO INCREASE INTO TRIPLE FIGURES M2/S2
ON BUFR SOUNDINGS AT KFAY AND KRWI BY 21Z. BUFR SOUNDINGS ALSO SHOW
SOME EROSION THE CAP...AND WHILE THE WINDOW IS NARROW...LIKELY ONLY
AROUND 19Z TO 22Z OR SO...THERE IS A NON-ZERO THREAT OF STRONGER...
DEEP CONVECTION MONDAY AFTERNOON BUT FOR THIS FORECAST WILL HOLD OFF
ON THE MENTION OF THUNDER IN ORDER TO EVALUATE TRENDS. IS THE
SURFACE LOW IS DEEPER OR SURFACE DEW POINTS START TO FIND THEIR WAY
MORE INTO THE 60S IN THE FAR EAST MONDAY AFTERNOON...THE POTENTIAL
FOR LOCAL SEVERE WEATHER COULD INCREASE.
GIVEN THE DISPARITY IN THE MODEL GUIDANCE LOWS FOR SUNDAY NIGHT...
AND UNCERTAINTY IN HOW QUICKLY LOWER CLOUDS AND PRECIPITATION MAY
DEVELOP...OPTED FOR A BLEND OF MOS VALUES FOR LOWS SUNDAY NIGHT IN
THE LOWER TO MID 40S. ON MONDAY...CERTAINLY A CHALLENGE IN TERMS OF
THE HIGHS CONSIDERING ANY COLD-AIR DAMMING...AND FOR THIS FORECAST
WILL HAVE MAXES IN THE LOWER TO MID 50S IN THE IMMEDIATE TRIAD... TO
NEAR 70 TOWARD KFAY AND KCTZ. GIVEN THE INCREASE IN 850MB AND 925MB
WINDS EAST MONDAY AFTERNOON...THERE COULD BE A FEW GUSTS NEAR 30MPH
IN THE COASTAL PLAIN THEN.
FOR THE PERIOD MONDAY NIGHT THROUGH TUESDAY...WHILE THE GFS HAS BEEN
FASTER THAN THE ECMWF WITH THE PASSAGE OF THE COLD FRONT AND THE
RETURN OF MUCH COLDER AIR...EVEN THE SLOWER ECMWF WOULD SUGGEST THE
COLD AIR CHASING THE MOISTURE MONDAY NIGHT SUCH THAT DRYING SHOULD
OCCUR BEFORE PARTIAL THICKNESSES AND SURFACE WET BULB TEMPERATURES
FALL TO RESULT IN ANY NON-LIQUID PRECIPITATION LATE MONDAY NIGHT.
ANTICIPATING THE CHANCES FOR PRECIPITATION FALLING BELOW SLIGHT BY
12Z TUESDAY...CHANCE-TO-LIKELY POPS WEST TO EAST MONDAY EVENING
DIMINISH OVERNIGHT WITH DRYING BEHIND THE COLD FRONT. IF THERE WOULD
BE ANY NON-LIQUID PRECIPITATION...THE THOUGHT WOULD BE IT WOULD
OCCUR EAST OF U.S. 1 IMMEDIATELY AT THE END OF THE PRECIPITATION AND
HAVE NO IMPACT.
FROM THERE...COLD HIGH PRESSURE BUILDS INTO CENTRAL NORTH CAROLINA
WITH 1000-850MB THICKNESSES POSSIBLE FALLING INTO THE 1250S TUESDAY
NIGHT WHICH BY LOCAL STUDY RESULTS IN LOWS WELL INTO THE 20S AND
POSSIBLY INTO THE TEENS. FORECASTS OF MOISTURE ALOFT...WHICH
SOMETIMES RESULTS IN CHALLENGES FOR VERY COLD OVERNIGHT LOWS...ARE
DRY...WITH THE HIGH BUILDING IN MAKING FOR LIGHT WINDS AS WELL.
AFTER HIGHS ON TUESDAY THAT MAY CHALLENGE THE RECORD LOW MAXIMUM
TEMPERATURE AT KFAY DEPENDING ON THE MIDNIGHT TEMPERATURE EARLY
TUESDAY...OVERNIGHT LOWS TUESDAY NIGHT SHOULD BE CLOSE TO RECORDS AT
LEAST AT KGSO AND KRDU. THE DAYTIME HIGH WEDNESDAY AT KFAY WILL...
AGAIN...LIKELY BE CLOSE TO THE RECORD LOW MAXIMUM THERE BASED ON THE
EXPECTED HIGH TEMPERATURE FORECAST FROM THE 1000-850MB THICKNESSES.
WHILE HIGH PRESSURE WILL BE IN PLACE AT THE SURFACE...A MODEST MID-
LEVEL SHORTWAVE MOVING THROUGH OR NEAR CENTRAL NORTH CAROLINA LATE
WEDNESDAY COULD RESULT IN THE PASSAGE OF SOME MID- OR HIGH-LEVEL
CLOUDS THEN.
GRADUAL WARMING SHOULD TAKE PLACE DURING THE END OF THE WEEK AS THE
COLD...UPPER TROUGH STARTS TO RETREAT. OVERNIGHT LOWS THURSDAY NIGHT
ARE COMPLICATED BY THE POTENTIAL FOR SOME HIGH CLOUDS AS THE UPPER
FLOW BACKS. BY FRIDAY...A SURFACE FRONT SHOULD BE MOVING TOWARD THE
VIRGINIA BORDER FROM THE NORTH...AND WHILE HIGH PRESSURE OVER THE
GULF SHOULD LIMIT THE LOW-LEVEL MOISTURE RETURN TOWARD CENTRAL NORTH
CAROLINA...BY OVERNIGHT FRIDAY THERE IS WHAT WILL CURRENTLY BE
FORECAST AS A SLIGHT CHANCE OF RAIN MAINLY IN THE INTERSTATE 85
CORRIDOR. PARTIAL THICKNESSES ARE WELL TOO WARM FOR ANYTHING BUT
LIQUID...BUT NOT CONFIDENT ENOUGH IN THE MOISTURE RETURN OR FRONTAL
CONVERGENCE TO FORECAST POPS BEYOND SLIGHT AT THIS POINT. BY
FRIDAY...TEMPERATURES SHOULD FINALLY RETURN CLOSE TO NORMAL.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 1235 AM SATURDAY...
24 HOUR TAF PERIOD: VERY HIGH CONFIDENCE OF VFR CONDITIONS
PERSISTING THROUGH THE TAF PERIOD AS HIGH PRESSURE BEGINS TO MOVE
OVERHEAD. THAT BEING SAID...THERE IS A THREAT TONIGHT FOR SOME LOW
LEVEL WIND SHEAR IN THE 500-1000 FT LAYER AT EASTERN SITES
(KRDU...KFAY...AND ESPECIALLY KRWI) WHERE WIND SPEEDS WILL GO FROM
RELATIVELY LIGHT AT 500 FT TO 25-30 KTS OR SO AT 1000 FT. THIS IS
BACKED UP BY WIND PROFILER DATA AT 530Z SHOWING 1 KT AT THE SURFACE
AND 33 KTS AT 900 FT. RAP FORECAST SOUNDINGS SHOW THIS ACTIVITY
CONTINUING UNTIL 13-14Z SATURDAY MORNING. OTHERWISE MOSTLY CLEAR
SKIES OVERNIGHT WITH LIGHT NORTHWESTERLY WINDS SHIFTING TO
NORTHEASTERLY DURING THE OVERNIGHT HOURS. FOR SATURDAY EXPECT WINDS
5-10 KTS OUT OF THE NORTHEAST THEN POSSIBLY SHIFTING TO A MORE
EASTERLY DIRECTION LATER IN THE AFTERNOON. BY 00Z OR SO SOME MID TO
HIGH LEVEL CLOUDS MAY START TO FILTER IN ABOVE 10 KFT.
LONG TERM: THE NEXT THREAT TO SUB-VFR CONDITIONS WILL COME ON MONDAY
AS A FRONTAL SYSTEM STARTS TO CROSS THE APPALACHIANS. HIGH PRESSURE
WILL THEN RETURN ON TUESDAY FOR THE REMAINDER OF THE WEEK.
&&
.CLIMATE...
THE FOLLOWING ARE RECORD TEMPERATURES THAT WILL BE CHALLENGED
THROUGH THE FORECAST PERIOD:
RECORD LOW:
GSO RDU FAY
SAT 11/15 - 20 IN 1969 21 IN 1969 22 IN 1942
WED 11/19 - 20 IN 1951 21 IN 1903 21 IN 1959
THU 11/20 - 12 IN 1951 19 IN 1951 20 IN 1951
RECORD LOW MAX:
GSO RDU FAY
TUE 11/18 - 37 IN 1924 35 IN 1924 46 IN 2008
WED 11/19 - 34 IN 1951 36 IN 1951 41 IN 2000
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...WSS
LONG TERM...DJF
AVIATION...ELLIS
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1236 PM EST FRI NOV 14 2014
.SYNOPSIS...HIGH PRESSURE WILL SETTLE OVER THE REGION ON SATURDAY...
THEN SHIFT OFFSHORE SUNDAY AND SUNDAY NIGHT AS A COLD FRONT
APPROACHES THE MOUNTAINS FROM THE WEST. THE COLD FRONT WILL SURGE
EASTWARD THROUGH THE CAROLINAS MONDAY EVENING.
&&
.NEAR TERM /TONIGHT/...
AS OF 730 PM FRIDAY...
MODIFIED ARCTIC HIGH PRESSURE BUILDING INTO THE REGION THIS EVENING
WILL SETTLE OVERHEAD TONIGHT. WITH CLEAR SKIES AND A COLD/DRY
AIRMASS IN PLACE...THE ONLY MITIGATING FACTOR W/REGARD TO THE
REALIZATION OF FULL RADIATIONAL COOLING WILL BE A LIGHT NW BREEZE
THROUGH 06-09Z. HOWEVER...PREVIOUS EXPERIENCE WOULD SUGGEST THAT
SEVERAL HRS OF CALM CONDITIONS PRIOR TO SUNRISE SHOULD BE SUFFICIENT
FOR LOWS IN THE LOW/MID 20S...PERHAPS UPPER TEENS IN A FEW
LOCATIONS WHERE WINDS REMAIN CALM FROM MIDNIGHT ONWARD. -VINCENT
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 250 PM FRIDAY...
SURFACE HIGH OVER THE FORECAST AREA WILL DRIFT EAST...THOUGH SURFACE
RIDGE AXIS WILL LINGER/EXTEND ACROSS THE REGION THROUGH EARLY
SUNDAY. WHILE THE LOWEST 10K OF THE ATMOSPHERE WILL BE TOO DRY TO
SUPPORT ANY CLOUDS...THE WLY FLOW ALOFT MAY ADVECT ENOUGH MOISTURE
TO CAUSE AREAS OF CIRRUS OVERHEAD LATE SATURDAY MORNING THROUGH
THE AFTERNOON. AT THIS TIME ANTICIPATE THE HIGH CLOUDS TO BE
THIN...SO THEY SHOULD NOT HAVE ANY IMPACTS ON TEMPS. IF CIRRUS
SHIELD THICKER/DENSER THAN CURRENTLY ANTICIPATED...THEN MAX
TEMPS MAY END UP BEING 3-4 DEGREES COOLER THAN FORECAST. THE DRY AIR
MASS WILL ALLOW TEMPS TO REBOUND FROM A FRIGID START. AFTERNOON
TEMPS SHOULD BE IN THE MID-UPPER 40S.
MODEL RH CROSS SECTIONS SUGGEST HIGH CLOUDS DEPARTING THE REGION
EARLY SATURDAY EVENING WITH MAINLY CLEAR SKIES FOR MOST OF THE NIGHT
UNTIL THE NEXT ROUND OF HIGH CLOUDS APPROACHES FROM THE WEST AROUND
DAYBREAK SUNDAY. THE MAINLY CLEAR SKIES AND CALM WINDS WILL AGAIN
ALLOW TEMPS TO FALL QUICKLY AFTER SUNSET. EXPECT MIN TEMPS SOLIDLY
IN THE MID-UPPER 20S.
SUNDAY...AS SURFACE HIGH RETREATS FARTHER AWAY FROM CENTRAL NC...THE
LOW LEVEL RETURN SLY FLOW WILL ADVECT MOISTURE OFF THE ATLANTIC INTO
THE SOUTHERN AND EASTERN SECTIONS OF CENTRAL NC. MODEL RH PLANE VIEW
PLOTS SUGGEST THE AIR MASS BETWEEN 925-850 MB ADEQUATELY MOIST TO
SUPPORT A DECK OF STRATOCU ACROSS THE SOUTHERN
PIEDMONT...SANDHILLS...AND SOUTHERN COASTAL PLAIN BY SUNDAY
AFTERNOON. OTHERWISE HIGH CLOUDS WILL THICKEN OVERHEAD ELSEWHERE IN
ADVANCE OF THE NEXT LOW PRESSURE SYSTEM. THERE MAY BE ENOUGH
ISENTROPIC UPGLIDE TO PERMIT THE DEVELOPMENT OF SPOTTY LIGHT RAIN
OVER THE FAR SOUTH-SE AND POSSIBLY THE FAR NW PRIOR TO SUNSET SUNDAY.
HIGH TEMPS SUNDAY WILL BE DICTATED TO THE EXTENT OF CLOUD COVER.
AIR MASS PROJECTED TO MODIFY WITH LOW LEVEL THICKNESSES IN THE MID
1330S. THESE VALUES STILL ABOUT 15M BELOW NORMAL...SUPPORTIVE OF MAX
TEMPS IN THE MID-UPPER 50S. SINCE EXPECTING THICKENING CLOUD
COVER...MAX TEMPS SHOULD TOP OUT IN THE LOW-MID 50S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
AS OF 305 PM FRIDAY...
FOR THE PERIOD SUNDAY NIGHT THROUGH MONDAY...A SERIES OF MID-LEVEL
SHORTWAVES ARE FORECAST TO MOVE THROUGH CENTRAL NORTH CAROLINA WITH
THE BEST LIFT FORECAST BY BOTH THE NAM AND GFS DURING THE DAY
MONDAY. THE NAM IS DRY FOR A LARGE PART OF SUNDAY NIGHT...WHICH IS
CLOSER TO WHAT THE 12Z ECMWF IS FORECASTING...WHILE THE GFS
SATURATES THE AIR MASS MUCH MORE QUICKLY SUNDAY NIGHT. BETTER 700MB
VORTICITY IS FORECAST MONDAY BY BOTH THE NAM AND THE GFS...AND THE
GREATER 850MB THETA-E AND K INDICES OCCUR THEN ALONG WITH THE
PASSAGE OF BETTER VORTICITY ON THE 1.5PVU SURFACE AS THE RIGHT
ENTRANCE REGION OF A 100KT 500MB JET APPROACHES LATE IN THE DAY.
FOR THIS FORECAST...EVEN THE DRIER NAM PROVIDES FOR LIKELY CHANCES
FOR RAIN IN THE TRIAD BY LATE SUNDAY NIGHT AND WILL BASICALLY
FORECAST LIKELY CHANCES THERE AND TOWARD ALBEMARLE AFTER MIDNIGHT
WITH CHANCES ELSEWHERE. FOR MONDAY...POPS WILL BE LIKELY WEST OF
INTERSTATE 95 FOR MUCH OF THE DAY...WITH LIKELY POPS ALONG AND EAST
OF INTERSTATE 95 AS THE 850MB THETA-E VALUES ARE MAXIMIZED IN
CENTRAL NORTH CAROLINA DURING THE AFTERNOON. AROUND 18Z...THE GFS
FORECASTS 850MB WINDS INCREASING TO AROUND 60KT IN THE COASTAL PLAIN
COINCIDENT WITH THE INCREASE IN 850MB THETA-E.
MUCAPE FROM 1000-500MB IS ONLY 100-200J/KG IN THE INTERSTATE 95
CORRIDOR MONDAY...AND NAM AND GFS BUFR SOUNDINGS SHOW LAPSE RATES
NEAR MOIST ADIABATIC. HOWEVER...THE 0-3KM SHEAR IS AROUND 50KT...
AND 0-3KM HELICITY IS FORECAST TO INCREASE INTO TRIPLE FIGURES M2/S2
ON BUFR SOUNDINGS AT KFAY AND KRWI BY 21Z. BUFR SOUNDINGS ALSO SHOW
SOME EROSION THE CAP...AND WHILE THE WINDOW IS NARROW...LIKELY ONLY
AROUND 19Z TO 22Z OR SO...THERE IS A NON-ZERO THREAT OF STRONGER...
DEEP CONVECTION MONDAY AFTERNOON BUT FOR THIS FORECAST WILL HOLD OFF
ON THE MENTION OF THUNDER IN ORDER TO EVALUATE TRENDS. IS THE
SURFACE LOW IS DEEPER OR SURFACE DEW POINTS START TO FIND THEIR WAY
MORE INTO THE 60S IN THE FAR EAST MONDAY AFTERNOON...THE POTENTIAL
FOR LOCAL SEVERE WEATHER COULD INCREASE.
GIVEN THE DISPARITY IN THE MODEL GUIDANCE LOWS FOR SUNDAY NIGHT...
AND UNCERTAINTY IN HOW QUICKLY LOWER CLOUDS AND PRECIPITATION MAY
DEVELOP...OPTED FOR A BLEND OF MOS VALUES FOR LOWS SUNDAY NIGHT IN
THE LOWER TO MID 40S. ON MONDAY...CERTAINLY A CHALLENGE IN TERMS OF
THE HIGHS CONSIDERING ANY COLD-AIR DAMMING...AND FOR THIS FORECAST
WILL HAVE MAXES IN THE LOWER TO MID 50S IN THE IMMEDIATE TRIAD... TO
NEAR 70 TOWARD KFAY AND KCTZ. GIVEN THE INCREASE IN 850MB AND 925MB
WINDS EAST MONDAY AFTERNOON...THERE COULD BE A FEW GUSTS NEAR 30MPH
IN THE COASTAL PLAIN THEN.
FOR THE PERIOD MONDAY NIGHT THROUGH TUESDAY...WHILE THE GFS HAS BEEN
FASTER THAN THE ECMWF WITH THE PASSAGE OF THE COLD FRONT AND THE
RETURN OF MUCH COLDER AIR...EVEN THE SLOWER ECMWF WOULD SUGGEST THE
COLD AIR CHASING THE MOISTURE MONDAY NIGHT SUCH THAT DRYING SHOULD
OCCUR BEFORE PARTIAL THICKNESSES AND SURFACE WET BULB TEMPERATURES
FALL TO RESULT IN ANY NON-LIQUID PRECIPITATION LATE MONDAY NIGHT.
ANTICIPATING THE CHANCES FOR PRECIPITATION FALLING BELOW SLIGHT BY
12Z TUESDAY...CHANCE-TO-LIKELY POPS WEST TO EAST MONDAY EVENING
DIMINISH OVERNIGHT WITH DRYING BEHIND THE COLD FRONT. IF THERE WOULD
BE ANY NON-LIQUID PRECIPITATION...THE THOUGHT WOULD BE IT WOULD
OCCUR EAST OF U.S. 1 IMMEDIATELY AT THE END OF THE PRECIPITATION AND
HAVE NO IMPACT.
FROM THERE...COLD HIGH PRESSURE BUILDS INTO CENTRAL NORTH CAROLINA
WITH 1000-850MB THICKNESSES POSSIBLE FALLING INTO THE 1250S TUESDAY
NIGHT WHICH BY LOCAL STUDY RESULTS IN LOWS WELL INTO THE 20S AND
POSSIBLY INTO THE TEENS. FORECASTS OF MOISTURE ALOFT...WHICH
SOMETIMES RESULTS IN CHALLENGES FOR VERY COLD OVERNIGHT LOWS...ARE
DRY...WITH THE HIGH BUILDING IN MAKING FOR LIGHT WINDS AS WELL.
AFTER HIGHS ON TUESDAY THAT MAY CHALLENGE THE RECORD LOW MAXIMUM
TEMPERATURE AT KFAY DEPENDING ON THE MIDNIGHT TEMPERATURE EARLY
TUESDAY...OVERNIGHT LOWS TUESDAY NIGHT SHOULD BE CLOSE TO RECORDS AT
LEAST AT KGSO AND KRDU. THE DAYTIME HIGH WEDNESDAY AT KFAY WILL...
AGAIN...LIKELY BE CLOSE TO THE RECORD LOW MAXIMUM THERE BASED ON THE
EXPECTED HIGH TEMPERATURE FORECAST FROM THE 1000-850MB THICKNESSES.
WHILE HIGH PRESSURE WILL BE IN PLACE AT THE SURFACE...A MODEST MID-
LEVEL SHORTWAVE MOVING THROUGH OR NEAR CENTRAL NORTH CAROLINA LATE
WEDNESDAY COULD RESULT IN THE PASSAGE OF SOME MID- OR HIGH-LEVEL
CLOUDS THEN.
GRADUAL WARMING SHOULD TAKE PLACE DURING THE END OF THE WEEK AS THE
COLD...UPPER TROUGH STARTS TO RETREAT. OVERNIGHT LOWS THURSDAY NIGHT
ARE COMPLICATED BY THE POTENTIAL FOR SOME HIGH CLOUDS AS THE UPPER
FLOW BACKS. BY FRIDAY...A SURFACE FRONT SHOULD BE MOVING TOWARD THE
VIRGINIA BORDER FROM THE NORTH...AND WHILE HIGH PRESSURE OVER THE
GULF SHOULD LIMIT THE LOW-LEVEL MOISTURE RETURN TOWARD CENTRAL NORTH
CAROLINA...BY OVERNIGHT FRIDAY THERE IS WHAT WILL CURRENTLY BE
FORECAST AS A SLIGHT CHANCE OF RAIN MAINLY IN THE INTERSTATE 85
CORRIDOR. PARTIAL THICKNESSES ARE WELL TOO WARM FOR ANYTHING BUT
LIQUID...BUT NOT CONFIDENT ENOUGH IN THE MOISTURE RETURN OR FRONTAL
CONVERGENCE TO FORECAST POPS BEYOND SLIGHT AT THIS POINT. BY
FRIDAY...TEMPERATURES SHOULD FINALLY RETURN CLOSE TO NORMAL.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 1235 AM SATURDAY...
24 HOUR TAF PERIOD: VERY HIGH CONFIDENCE OF VFR CONDITIONS
PERSISTING THROUGH THE TAF PERIOD AS HIGH PRESSURE BEGINS TO MOVE
OVERHEAD. THAT BEING SAID...THERE IS A THREAT TONIGHT FOR SOME LOW
LEVEL WIND SHEAR IN THE 500-1000 FT LAYER AT EASTERN SITES
(KRDU...KFAY...AND ESPECIALLY KRWI) WHERE WIND SPEEDS WILL GO FROM
RELATIVELY LIGHT AT 500 FT TO 25-30 KTS OR SO AT 1000 FT. THIS IS
BACKED UP BY WIND PROFILER DATA AT 530Z SHOWING 1 KT AT THE SURFACE
AND 33 KTS AT 900 FT. RAP FORECAST SOUNDINGS SHOW THIS ACTIVITY
CONTINUING UNTIL 13-14Z SATURDAY MORNING. OTHERWISE MOSTLY CLEAR
SKIES OVERNIGHT WITH LIGHT NORTHWESTERLY WINDS SHIFTING TO
NORTHEASTERLY DURING THE OVERNIGHT HOURS. FOR SATURDAY EXPECT WINDS
5-10 KTS OUT OF THE NORTHEAST THEN POSSIBLY SHIFTING TO A MORE
EASTERLY DIRECTION LATER IN THE AFTERNOON. BY 00Z OR SO SOME MID TO
HIGH LEVEL CLOUDS MAY START TO FILTER IN ABOVE 10 KFT.
LONG TERM: THE NEXT THREAT TO SUB-VFR CONDITIONS WILL COME ON MONDAY
AS A FRONTAL SYSTEM STARTS TO CROSS THE APPALACHIANS. HIGH PRESSURE
WILL THEN RETURN ON TUESDAY FOR THE REMAINDER OF THE WEEK.
&&
.CLIMATE...
THE FOLLOWING ARE RECORD TEMPERATURES THAT WILL BE CHALLENGED
THROUGH THE FORECAST PERIOD:
RECORD LOW:
GSO RDU FAY
SAT 11/15 - 20 IN 1969 21 IN 1969 22 IN 1942
WED 11/19 - 20 IN 1951 21 IN 1903 21 IN 1959
THU 11/20 - 12 IN 1951 19 IN 1951 20 IN 1951
RECORD LOW MAX:
GSO RDU FAY
TUE 11/18 - 37 IN 1924 35 IN 1924 46 IN 2008
WED 11/19 - 34 IN 1951 36 IN 1951 41 IN 2000
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...WSS
LONG TERM...DJF
AVIATION...ELLIS
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1219 PM CST SAT NOV 15 2014
.UPDATE...
ISSUED AT 1220 PM CST SAT NOV 15 2014
CONTINUED TO EXPAND ISOLATED FLURRIES SOUTHEAST AS THE STRATUS
DECK WITH EMBEDDED FLURRIES CONTINUES TO DRIFT SOUTH OVER WESTERN
AND CENTRAL NORTH DAKOTA THIS AFTERNOON.
FOCUS THEN SHIFTS TO WINDS AND BLOWING SNOW POTENTIAL SUNDAY. WILL
CONTINUE TO COLLABORATE WITH SURROUNDING OFFICES TO ENSURE
CONSISTENT HEADLINES. WILL HAVE HEADLINE DECISIONS REACHED BY THE
MID-AFTERNOON UPDATE TIME.
UPDATE ISSUED AT 839 AM CST SAT NOV 15 2014
UPDATED THE FORECAST TO CANCEL THE WIND CHILL ADVISORY FOR WEST
CENTRAL AND NORTHWESTERN NORTH DAKOTA THIS MORNING.
11-3.9 MICRON SATELLITE IMAGERY SHOWS A STRATUS DECK BEGINNING TO
DRIFT SOUTH ACROSS NORTHWESTERN NORTH DAKOTA. ISOLATED FLURRIES
HAVE BEEN REPORTED UNDER THIS STATUS DECK. AS A RESULT...ADDED
ISOLATED FLURRIES TO THE FORECAST NORTHWEST THIS MORNING. THE
STRATUS SHOULD BEGIN TO BREAK UP SOMEWHAT BY THIS AFTERNOON. THE
REMAINING WEATHER ELEMENTS ARE IN GOOD SHAPE. THE UPDATED PRODUCTS
HAVE BEEN SENT.
UPDATE ISSUED AT 653 AM CST SAT NOV 15 2014
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE OTHER THAN TO
BLEND TO OBSERVED TRENDS THROUGH 12 UTC. WILL LEAVE THE WIND CHILL
ADVISORY IN PLACE AS BORDERLINE ADVISORY CRITERIA VALUES NEAR -25
WILL CONTINUE EARLY THIS MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CST SAT NOV 15 2014
MAIN HIGHLIGHT THIS MORNING IS A WIND CHILL ADVISORY FOR PORTIONS OF
THE FAR WEST. COLDER AIR COMING IN FROM THE WEST AND BRISK WINDS
WILL DOMINATE THROUGH MID MORNING. A POTENT SHORTWAVE AND ASSOCIATED
COLD FRONT SHIFTING SOUTH FROM CENTRAL CANADA WILL BEGIN TO IMPACT
WESTERN/NORTHERN NORTH DAKOTA LATE SATURDAY NIGHT THEN SPREAD SOUTH
SUNDAY MORNING.
THE LATEST WATER VAPOR IMAGERY SHOWS AN ELONGATED UPPER TROUGH
FROM HUDSON BAY SOUTHWEST INTO MONTANA. AHEAD OF THE TROUGH...A
SHORTWAVE WAS SEEN ALONG THE WYOMING/MONTANA BORDER MOVING EAST TO
SOUTHEAST WITH TIME...AS THE SURFACE LOW REMAINS FARTHER SOUTH.
LIGHT SNOW ASSOCIATED WITH THIS SYSTEM EXTENDED ACROSS CENTRAL AND
SOUTHERN SOUTH DAKOTA AND IS MOVING EAST. FARTHER UPSTREAM...AN
AREA OF STRATUS OVER SOUTHERN SASKATCHEWAN PER LATEST FOG/STRATUS
LOOP CONTINUES A SOUTHEAST MOVEMENT. THE HRRR AND RAP13 SHIFT THIS
INTO NORTHWEST AND NORTH CENTRAL NORTH DAKOTA BETWEEN 12Z-21Z
TODAY. CONCUR WITH THIS AND ADJUSTED SKY GRIDS ACCORDINGLY.
ELSEWHERE ISOLATED FLURRIES WITH POCKETS OF STRATUS CONTINUE EARLY
THIS MORNING IN THE FAR SOUTHWEST...ALONG AND SOUTH OF LAKE
SAKAKAWEA...AND IN THE SOUTHERN JAMES RIVER VALLEY. ANOTHER VERY
COLD DAY AHEAD WITH HIGHS IN THE SINGLE DIGITS ABOVE ZERO IN THE
WEST AND SOUTHWEST...TO LOWER/MIDDLE TEENS ELSEWHERE. BRISK
NORTHWEST WINDS THIS AFTERNOON 10 TO 25 MPH.
FOR TONIGHT...ATTENTION TURNS TO A STRONG SHORTWAVE TROUGH AND
ASSOCIATED SHARP COLD FRONT HEADING DUE SOUTH FROM THE NORTHWEST
TERRITORIES. THE COLD FRONT WILL PASS THROUGH NORTHWEST AND NORTH
CENTRAL AFTER MIDNIGHT WITH INCREASING WINDS TOWARD AND SHORTLY
AFTER DAYBREAK ON SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 406 AM CST SAT NOV 15 2014
BLOWING SNOW POTENTIAL ON SUNDAY HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE CONTINUES THE TREND OVER THE PAST
SEVERAL DAYS OF A REINFORCING COLD FRONT TO PROPAGATE ACROSS
WESTERN AND CENTRAL NORTH DAKOTA SUNDAY MORNING IN ASSOCIATION
WITH ITS PARENT CLIPPER SYSTEM ACROSS EASTERN MANITOBA INTO
WESTERN ONTARIO. STRONG NORTHWEST WINDS INTERACTING WITH THE
SNOWFALL FROM LAST WEEKEND PRESENTS A BLOWING SNOW THREAT. THE
CHALLENGE IS IF BLIZZARD CRITERIA WILL BE MET ACROSS THE SOUTHWEST
WHERE THE MOST SNOW WAS RECEIVED. THE SNOW HAS BEEN ON THE GROUND
FOR A WEEK...HOWEVER...IT IS UNCRUSTED AND HAS NOT BEEN
SIGNIFICANTLY COMPACTED. THAT SAID....BEING THE FIRST SNOWFALL OF
THE SEASON...SOME OF THE SNOW MAY BE ADVERSE TO BEING LOFTED FROM
BEING TRAPPED IN THE GRASSES. THUS...WILL FORGO A BLIZZARD WATCH
FOR NOW...AND HIGHLIGHT THE THREAT WITH NEAR-BLIZZARD CONDITIONS
POSSIBLE IN THE REMAINDER OF THE PRODUCT SUITE AND SPECIAL WEATHER
STATEMENT. PROBABILITIES FOR HALF-MILE VISIBILITIES USING THE
BAGGALY BLOWING SNOW MODEL TAKING INTO ACCOUNT SNOW AGE AND THE
LACK OF SIGNIFICANT FALLING SNOW PRODUCE RESULTS THAT DO NOT FAVOR
BLIZZARD CRITERIA BEING MET. FURTHERMORE...THE STRENGTH OF
ISALLOBARIC FORCING AND WINDS AT THE TOP OF THE MIXED LAYER
DECREASE THROUGH THE DAY...BEING GREATEST PRIOR TO THE PRE-FRONTAL
INVERSION BEING BROKEN. CERTAINLY AT LEAST A WINTER WEATHER
ADVISORY FOR BLOWING SNOW WILL BE NEEDED FOR THE SOUTHWEST...AND
POSSIBLY INTO THE SOUTH CENTRAL. GIVEN FURTHER EVALUATION
TODAY.... WOULD NOT BE SURPRISED IF A BLIZZARD WATCH IS ISSUED.
THEREAFTER...THE DE-AMPLIFICATION OF THE ANOMALOUS UPPER LEVEL
PATTERN IS SLOWER WITH THE 15/00 UTC GUIDANCE CONSENSUS COMPARED
TO PREVIOUS RUNS...WITH A RECOVERY FROM ARCTIC AIR LIKELY DELAYED
UNTIL LATE NEXT WEEK AT THE EARLIEST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1220 PM CST SAT NOV 15 2014
MVFR CIGS WILL CONTINUE TO DRIFT SOUTH OVER WESTERN AND CENTRAL
NORTH DAKOTA THIS AFTERNOON. ISOLATED FLURRIES ARE EMBEDDED WITHIN
THE STRATUS DECK. INDICATED VCSH IN THE AFTERNOON TAFS TO ACCOUNT
FOR THESE FLURRIES. OTHERWISE...VFR CONDITIONS ARE EXPECTED TO
DEVELOP OVERNIGHT. A COLD FRONT WILL THEN SWEEP ACROSS THE STATE
FROM NORTH TO SOUTH SUNDAY MORNING...WITH WINDY CONDITIONS
DEVELOPING IN ITS WAKE SUNDAY AFTERNOON. BLOWING SNOW WILL BE
POSSIBLE MAINLY OVER KDIK SUNDAY...WITH IFR VSBYS EXPECTED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...KS
LONG TERM...AYD
AVIATION...TM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
839 AM CST SAT NOV 15 2014
.UPDATE...
ISSUED AT 839 AM CST SAT NOV 15 2014
UPDATED THE FORECAST TO CANCEL THE WIND CHILL ADVISORY FOR WEST
CENTRAL AND NORTHWESTERN NORTH DAKOTA THIS MORNING.
11-3.9 MICRON SATELLITE IMAGERY SHOWS A STRATUS DECK BEGINNING TO
DRIFT SOUTH ACROSS NORTHWESTERN NORTH DAKOTA. ISOLATED FLURRIES
HAVE BEEN REPORTED UNDER THIS STATUS DECK. AS A RESULT...ADDED
ISOLATED FLURRIES TO THE FORECAST NORTHWEST THIS MORNING. THE
STRATUS SHOULD BEGIN TO BREAK UP SOMEWHAT BY THIS AFTERNOON. THE
REMAINING WEATHER ELEMENTS ARE IN GOOD SHAPE. THE UPDATED PRODUCTS
HAVE BEEN SENT.
UPDATE ISSUED AT 653 AM CST SAT NOV 15 2014
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE OTHER THAN TO
BLEND TO OBSERVED TRENDS THROUGH 12 UTC. WILL LEAVE THE WIND CHILL
ADVISORY IN PLACE AS BORDERLINE ADVISORY CRITERIA VALUES NEAR -25
WILL CONTINUE EARLY THIS MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CST SAT NOV 15 2014
MAIN HIGHLIGHT THIS MORNING IS A WIND CHILL ADVISORY FOR PORTIONS OF
THE FAR WEST. COLDER AIR COMING IN FROM THE WEST AND BRISK WINDS
WILL DOMINATE THROUGH MID MORNING. A POTENT SHORTWAVE AND ASSOCIATED
COLD FRONT SHIFTING SOUTH FROM CENTRAL CANADA WILL BEGIN TO IMPACT
WESTERN/NORTHERN NORTH DAKOTA LATE SATURDAY NIGHT THEN SPREAD SOUTH
SUNDAY MORNING.
THE LATEST WATER VAPOR IMAGERY SHOWS AN ELONGATED UPPER TROUGH
FROM HUDSON BAY SOUTHWEST INTO MONTANA. AHEAD OF THE TROUGH...A
SHORTWAVE WAS SEEN ALONG THE WYOMING/MONTANA BORDER MOVING EAST TO
SOUTHEAST WITH TIME...AS THE SURFACE LOW REMAINS FARTHER SOUTH.
LIGHT SNOW ASSOCIATED WITH THIS SYSTEM EXTENDED ACROSS CENTRAL AND
SOUTHERN SOUTH DAKOTA AND IS MOVING EAST. FARTHER UPSTREAM...AN
AREA OF STRATUS OVER SOUTHERN SASKATCHEWAN PER LATEST FOG/STRATUS
LOOP CONTINUES A SOUTHEAST MOVEMENT. THE HRRR AND RAP13 SHIFT THIS
INTO NORTHWEST AND NORTH CENTRAL NORTH DAKOTA BETWEEN 12Z-21Z
TODAY. CONCUR WITH THIS AND ADJUSTED SKY GRIDS ACCORDINGLY.
ELSEWHERE ISOLATED FLURRIES WITH POCKETS OF STRATUS CONTINUE EARLY
THIS MORNING IN THE FAR SOUTHWEST...ALONG AND SOUTH OF LAKE
SAKAKAWEA...AND IN THE SOUTHERN JAMES RIVER VALLEY. ANOTHER VERY
COLD DAY AHEAD WITH HIGHS IN THE SINGLE DIGITS ABOVE ZERO IN THE
WEST AND SOUTHWEST...TO LOWER/MIDDLE TEENS ELSEWHERE. BRISK
NORTHWEST WINDS THIS AFTERNOON 10 TO 25 MPH.
FOR TONIGHT...ATTENTION TURNS TO A STRONG SHORTWAVE TROUGH AND
ASSOCIATED SHARP COLD FRONT HEADING DUE SOUTH FROM THE NORTHWEST
TERRITORIES. THE COLD FRONT WILL PASS THROUGH NORTHWEST AND NORTH
CENTRAL AFTER MIDNIGHT WITH INCREASING WINDS TOWARD AND SHORTLY
AFTER DAYBREAK ON SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 406 AM CST SAT NOV 15 2014
BLOWING SNOW POTENTIAL ON SUNDAY HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE CONTINUES THE TREND OVER THE PAST
SEVERAL DAYS OF A REINFORCING COLD FRONT TO PROPAGATE ACROSS
WESTERN AND CENTRAL NORTH DAKOTA SUNDAY MORNING IN ASSOCIATION
WITH ITS PARENT CLIPPER SYSTEM ACROSS EASTERN MANITOBA INTO
WESTERN ONTARIO. STRONG NORTHWEST WINDS INTERACTING WITH THE
SNOWFALL FROM LAST WEEKEND PRESENTS A BLOWING SNOW THREAT. THE
CHALLENGE IS IF BLIZZARD CRITERIA WILL BE MET ACROSS THE SOUTHWEST
WHERE THE MOST SNOW WAS RECEIVED. THE SNOW HAS BEEN ON THE GROUND
FOR A WEEK...HOWEVER...IT IS UNCRUSTED AND HAS NOT BEEN
SIGNIFICANTLY COMPACTED. THAT SAID....BEING THE FIRST SNOWFALL OF
THE SEASON...SOME OF THE SNOW MAY BE ADVERSE TO BEING LOFTED FROM
BEING TRAPPED IN THE GRASSES. THUS...WILL FORGO A BLIZZARD WATCH
FOR NOW...AND HIGHLIGHT THE THREAT WITH NEAR-BLIZZARD CONDITIONS
POSSIBLE IN THE REMAINDER OF THE PRODUCT SUITE AND SPECIAL WEATHER
STATEMENT. PROBABILITIES FOR HALF-MILE VISIBILITIES USING THE
BAGGALY BLOWING SNOW MODEL TAKING INTO ACCOUNT SNOW AGE AND THE
LACK OF SIGNIFICANT FALLING SNOW PRODUCE RESULTS THAT DO NOT FAVOR
BLIZZARD CRITERIA BEING MET. FURTHERMORE...THE STRENGTH OF
ISALLOBARIC FORCING AND WINDS AT THE TOP OF THE MIXED LAYER
DECREASE THROUGH THE DAY...BEING GREATEST PRIOR TO THE PRE-FRONTAL
INVERSION BEING BROKEN. CERTAINLY AT LEAST A WINTER WEATHER
ADVISORY FOR BLOWING SNOW WILL BE NEEDED FOR THE SOUTHWEST...AND
POSSIBLY INTO THE SOUTH CENTRAL. GIVEN FURTHER EVALUATION
TODAY.... WOULD NOT BE SURPRISED IF A BLIZZARD WATCH IS ISSUED.
THEREAFTER...THE DE-AMPLIFICATION OF THE ANOMALOUS UPPER LEVEL
PATTERN IS SLOWER WITH THE 15/00 UTC GUIDANCE CONSENSUS COMPARED
TO PREVIOUS RUNS...WITH A RECOVERY FROM ARCTIC AIR LIKELY DELAYED
UNTIL LATE NEXT WEEK AT THE EARLIEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 653 AM CST SAT NOV 15 2014
SATELLITE AND SURFACE OBSERVATIONS CONTINUE TO SHOW MVFR CIGS
ENTERING WESTERN AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA THIS
MORNING. THIS IS FORECAST TO PERSIST INTO THE EARLY AFTERNOON.
CIGS AT KDIK WILL FREQUENTLY VARY BETWEEN MVFR/IFR...WHILE MVFR
CIGS WILL CONTINUE TO FILL IN AT KBIS BY 13Z...AND INTO KMOT BY
16Z. KJMS WILL REMAIN VFR TODAY WITH MVFR CIGS SOUTH OF THE
TERMINAL.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
654 AM CST SAT NOV 15 2014
.UPDATE...
ISSUED AT 653 AM CST SAT NOV 15 2014
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE OTHER THAN TO
BLEND TO OBSERVED TRENDS THROUGH 12 UTC. WILL LEAVE THE WIND CHILL
ADVISORY IN PLACE AS BORDERLINE ADVISORY CRITERIA VALUES NEAR -25
WILL CONTINUE EARLY THIS MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CST SAT NOV 15 2014
MAIN HIGHLIGHT THIS MORNING IS A WIND CHILL ADVISORY FOR PORTIONS OF
THE FAR WEST. COLDER AIR COMING IN FROM THE WEST AND BRISK WINDS
WILL DOMINATE THROUGH MID MORNING. A POTENT SHORTWAVE AND ASSOCIATED
COLD FRONT SHIFTING SOUTH FROM CENTRAL CANADA WILL BEGIN TO IMPACT
WESTERN/NORTHERN NORTH DAKOTA LATE SATURDAY NIGHT THEN SPREAD SOUTH
SUNDAY MORNING.
THE LATEST WATER VAPOR IMAGERY SHOWS AN ELONGATED UPPER TROUGH
FROM HUDSON BAY SOUTHWEST INTO MONTANA. AHEAD OF THE TROUGH...A
SHORTWAVE WAS SEEN ALONG THE WYOMING/MONTANA BORDER MOVING EAST TO
SOUTHEAST WITH TIME...AS THE SURFACE LOW REMAINS FARTHER SOUTH.
LIGHT SNOW ASSOCIATED WITH THIS SYSTEM EXTENDED ACROSS CENTRAL AND
SOUTHERN SOUTH DAKOTA AND IS MOVING EAST. FARTHER UPSTREAM...AN
AREA OF STRATUS OVER SOUTHERN SASKATCHEWAN PER LATEST FOG/STRATUS
LOOP CONTINUES A SOUTHEAST MOVEMENT. THE HRRR AND RAP13 SHIFT THIS
INTO NORTHWEST AND NORTH CENTRAL NORTH DAKOTA BETWEEN 12Z-21Z
TODAY. CONCUR WITH THIS AND ADJUSTED SKY GRIDS ACCORDINGLY.
ELSEWHERE ISOLATED FLURRIES WITH POCKETS OF STRATUS CONTINUE EARLY
THIS MORNING IN THE FAR SOUTHWEST...ALONG AND SOUTH OF LAKE
SAKAKAWEA...AND IN THE SOUTHERN JAMES RIVER VALLEY. ANOTHER VERY
COLD DAY AHEAD WITH HIGHS IN THE SINGLE DIGITS ABOVE ZERO IN THE
WEST AND SOUTHWEST...TO LOWER/MIDDLE TEENS ELSEWHERE. BRISK
NORTHWEST WINDS THIS AFTERNOON 10 TO 25 MPH.
FOR TONIGHT...ATTENTION TURNS TO A STRONG SHORTWAVE TROUGH AND
ASSOCIATED SHARP COLD FRONT HEADING DUE SOUTH FROM THE NORTHWEST
TERRITORIES. THE COLD FRONT WILL PASS THROUGH NORTHWEST AND NORTH
CENTRAL AFTER MIDNIGHT WITH INCREASING WINDS TOWARD AND SHORTLY
AFTER DAYBREAK ON SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 406 AM CST SAT NOV 15 2014
BLOWING SNOW POTENTIAL ON SUNDAY HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE CONTINUES THE TREND OVER THE PAST
SEVERAL DAYS OF A REINFORCING COLD FRONT TO PROPAGATE ACROSS
WESTERN AND CENTRAL NORTH DAKOTA SUNDAY MORNING IN ASSOCIATION
WITH ITS PARENT CLIPPER SYSTEM ACROSS EASTERN MANITOBA INTO
WESTERN ONTARIO. STRONG NORTHWEST WINDS INTERACTING WITH THE
SNOWFALL FROM LAST WEEKEND PRESENTS A BLOWING SNOW THREAT. THE
CHALLENGE IS IF BLIZZARD CRITERIA WILL BE MET ACROSS THE SOUTHWEST
WHERE THE MOST SNOW WAS RECEIVED. THE SNOW HAS BEEN ON THE GROUND
FOR A WEEK...HOWEVER...IT IS UNCRUSTED AND HAS NOT BEEN
SIGNIFICANTLY COMPACTED. THAT SAID....BEING THE FIRST SNOWFALL OF
THE SEASON...SOME OF THE SNOW MAY BE ADVERSE TO BEING LOFTED FROM
BEING TRAPPED IN THE GRASSES. THUS...WILL FORGO A BLIZZARD WATCH
FOR NOW...AND HIGHLIGHT THE THREAT WITH NEAR-BLIZZARD CONDITIONS
POSSIBLE IN THE REMAINDER OF THE PRODUCT SUITE AND SPECIAL WEATHER
STATEMENT. PROBABILITIES FOR HALF-MILE VISIBILITIES USING THE
BAGGALY BLOWING SNOW MODEL TAKING INTO ACCOUNT SNOW AGE AND THE
LACK OF SIGNIFICANT FALLING SNOW PRODUCE RESULTS THAT DO NOT FAVOR
BLIZZARD CRITERIA BEING MET. FURTHERMORE...THE STRENGTH OF
ISALLOBARIC FORCING AND WINDS AT THE TOP OF THE MIXED LAYER
DECREASE THROUGH THE DAY...BEING GREATEST PRIOR TO THE PRE-FRONTAL
INVERSION BEING BROKEN. CERTAINLY AT LEAST A WINTER WEATHER
ADVISORY FOR BLOWING SNOW WILL BE NEEDED FOR THE SOUTHWEST...AND
POSSIBLY INTO THE SOUTH CENTRAL. GIVEN FURTHER EVALUATION
TODAY.... WOULD NOT BE SURPRISED IF A BLIZZARD WATCH IS ISSUED.
THEREAFTER...THE DE-AMPLIFICATION OF THE ANOMALOUS UPPER LEVEL
PATTERN IS SLOWER WITH THE 15/00 UTC GUIDANCE CONSENSUS COMPARED
TO PREVIOUS RUNS...WITH A RECOVERY FROM ARCTIC AIR LIKELY DELAYED
UNTIL LATE NEXT WEEK AT THE EARLIEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 653 AM CST SAT NOV 15 2014
SATELLITE AND SURFACE OBSERVATIONS CONTINUE TO SHOW MVFR CIGS
ENTERING WESTERN AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA THIS
MORNING. THIS IS FORECAST TO PERSIST INTO THE EARLY AFTERNOON.
CIGS AT KDIK WILL FREQUENTLY VARY BETWEEN MVFR/IFR...WHILE MVFR
CIGS WILL CONTINUE TO FILL IN AT KBIS BY 13Z...AND INTO KMOT BY
16Z. KJMS WILL REMAIN VFR TODAY WITH MVFR CIGS SOUTH OF THE
TERMINAL.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 10 AM CST /9 AM MST/ THIS MORNING FOR
NDZ001-009-017-018-031>033.
&&
$$
UPDATE...AYD
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
406 AM CST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CST SAT NOV 15 2014
MAIN HIGHLIGHT THIS MORNING IS A WIND CHILL ADVISORY FOR PORTIONS OF
THE FAR WEST. COLDER AIR COMING IN FROM THE WEST AND BRISK WINDS
WILL DOMINATE THROUGH MID MORNING. A POTENT SHORTWAVE AND ASSOCIATED
COLD FRONT SHIFTING SOUTH FROM CENTRAL CANADA WILL BEGIN TO IMPACT
WESTERN/NORTHERN NORTH DAKOTA LATE SATURDAY NIGHT THEN SPREAD SOUTH
SUNDAY MORNING.
THE LATEST WATER VAPOR IMAGERY SHOWS AN ELONGATED UPPER TROUGH
FROM HUDSON BAY SOUTHWEST INTO MONTANA. AHEAD OF THE TROUGH...A
SHORTWAVE WAS SEEN ALONG THE WYOMING/MONTANA BORDER MOVING EAST TO
SOUTHEAST WITH TIME...AS THE SURFACE LOW REMAINS FARTHER SOUTH.
LIGHT SNOW ASSOCIATED WITH THIS SYSTEM EXTENDED ACROSS CENTRAL AND
SOUTHERN SOUTH DAKOTA AND IS MOVING EAST. FARTHER UPSTREAM...AN
AREA OF STRATUS OVER SOUTHERN SASKATCHEWAN PER LATEST FOG/STRATUS
LOOP CONTINUES A SOUTHEAST MOVEMENT. THE HRRR AND RAP13 SHIFT THIS
INTO NORTHWEST AND NORTH CENTRAL NORTH DAKOTA BETWEEN 12Z-21Z
TODAY. CONCUR WITH THIS AND ADJUSTED SKY GRIDS ACCORDINGLY.
ELSEWHERE ISOLATED FLURRIES WITH POCKETS OF STRATUS CONTINUE EARLY
THIS MORNING IN THE FAR SOUTHWEST...ALONG AND SOUTH OF LAKE
SAKAKAWEA...AND IN THE SOUTHERN JAMES RIVER VALLEY. ANOTHER VERY
COLD DAY AHEAD WITH HIGHS IN THE SINGLE DIGITS ABOVE ZERO IN THE
WEST AND SOUTHWEST...TO LOWER/MIDDLE TEENS ELSEWHERE. BRISK
NORTHWEST WINDS THIS AFTERNOON 10 TO 25 MPH.
FOR TONIGHT...ATTENTION TURNS TO A STRONG SHORTWAVE TROUGH AND
ASSOCIATED SHARP COLD FRONT HEADING DUE SOUTH FROM THE NORTHWEST
TERRITORIES. THE COLD FRONT WILL PASS THROUGH NORTHWEST AND NORTH
CENTRAL AFTER MIDNIGHT WITH INCREASING WINDS TOWARD AND SHORTLY
AFTER DAYBREAK ON SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 406 AM CST SAT NOV 15 2014
BLOWING SNOW POTENTIAL ON SUNDAY HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE CONTINUES THE TREND OVER THE PAST
SEVERAL DAYS OF A REINFORCING COLD FRONT TO PROPAGATE ACROSS
WESTERN AND CENTRAL NORTH DAKOTA SUNDAY MORNING IN ASSOCIATION
WITH ITS PARENT CLIPPER SYSTEM ACROSS EASTERN MANITOBA INTO
WESTERN ONTARIO. STRONG NORTHWEST WINDS INTERACTING WITH THE
SNOWFALL FROM LAST WEEKEND PRESENTS A BLOWING SNOW THREAT. THE
CHALLENGE IS IF BLIZZARD CRITERIA WILL BE MET ACROSS THE SOUTHWEST
WHERE THE MOST SNOW WAS RECEIVED. THE SNOW HAS BEEN ON THE GROUND
FOR A WEEK...HOWEVER...IT IS UNCRUSTED AND HAS NOT BEEN
SIGNIFICANTLY COMPACTED. THAT SAID....BEING THE FIRST SNOWFALL OF
THE SEASON...SOME OF THE SNOW MAY BE ADVERSE TO BEING LOFTED FROM
BEING TRAPPED IN THE GRASSES. THUS...WILL FORGO A BLIZZARD WATCH
FOR NOW...AND HIGHLIGHT THE THREAT WITH NEAR-BLIZZARD CONDITIONS
POSSIBLE IN THE REMAINDER OF THE PRODUCT SUITE AND SPECIAL WEATHER
STATEMENT. PROBABILITIES FOR HALF-MILE VISIBILITIES USING THE
BAGGLEY BLOWING SNOW MODEL TAKING INTO ACCOUNT SNOW AGE AND THE
LACK OF SIGNIFICANT FALLING SNOW PRODUCE RESULTS THAT DO NOT FAVOR
BLIZZARD CRITERIA BEING MET. FURTHERMORE...THE STRENGTH OF
ISALLOBARIC FORCING AND WINDS AT THE TOP OF THE MIXED LAYER
DECREASE THROUGH THE DAY...BEING GREATEST PRIOR TO THE PRE-FRONTAL
INVERSION BEING BROKEN. CERTAINLY AT LEAST A WINTER WEATHER
ADVISORY FOR BLOWING SNOW WILL BE NEEDED FOR THE SOUTHWEST...AND
POSSIBLY INTO THE SOUTH CENTRAL. GIVEN FURTHER EVALUATION
TODAY.... WOULD NOT BE SURPRISED IF A BLIZZARD WATCH IS ISSUED.
THEREAFTER...THE DE-AMPLIFICATION OF THE ANOMALOUS UPPER LEVEL
PATTERN IS SLOWER WITH THE 15/00 UTC GUIDANCE CONSENSUS COMPARED
TO PREVIOUS RUNS...WITH A RECOVERY FROM ARCTIC AIR LIKELY DELAYED
UNTIL LATE NEXT WEEK AT THE EARLIEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 406 AM CST SAT NOV 15 2014
AN AREA OF MVFR CIGS OVER SASKATCHEWAN AND NORTHEAST MONTANA
CONTINUE TO SHIFT SOUTHEAST TOWARD KISN EARLY THIS MORNING. EXPECT
MVFR CIGS INTO KISN BETWEEN 10Z-12Z SATURDAY...AND INTO KMOT BY 15Z
SATURDAY. ELSEWHERE...POCKETS OF LOW VFR CIGS WILL CONTINUE OVER
KJMS THROUGH THE EARLY MORNING...WITH KDIK DETERIORATING FROM VFR TO
MVFR/IFR.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 10 AM CST /9 AM MST/ THIS MORNING FOR
NDZ001-009-017-018-031>033.
&&
$$
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1006 PM EST SUN NOV 16 2014
.SYNOPSIS...
A DEEP TROUGH ALOFT AND AN ARCTIC COLD FRONT WILL SWEEP ACROSS
THE AREA MONDAY. UNSEASONABLY COLD AIR WILL MOVE IN MONDAY NIGHT
AND TUESDAY AND THEN ANOTHER TROUGH WILL BE IN THE AREA FOR THE
END OF THE WORK WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
UPDATE...NO MAJOR CHANGES. DID ADJUST POPS DOWN NORTHWEST TO
REFLECT A LUL IN PRECIP AS FIRST WAVE MOVES NORTHEAST OF THE
AFTER TOWARDS OR JUST AFTER MIDNIGHT. DRYING ALREADY SHOWING UP IN
PORTIONS OF NORTHERN AND WRN INDIANA. HRRR HOWEVER DOES SHOW AT
LEAST LIGHT SNOW RETURNING BEFORE DAYBREAK BEFORE FINALLY ENDING
MONDAY MORNING. ALL ELSE ON TRACK FOR NOW.
ORIGINAL (CORRECTED)...THE SNOW WILL BE DEVELOPING SOMEWHAT
QUICKLY EARLY TONIGHT. ON THE EDGE WHETHER SOME MIX PRECIPITATION
WILL OCCUR. THIS MENTION A MIX OVER THE SOUTHERN COUNTIES BUT DID
NOT MENTION FREEZING RAIN. THE SNOWFALL AMOUNTS OF VERY TRICKY.
PLENTY OF OMEGA AND THE RIGHT REAR QUAD OF THE JET WILL HELP
THINGS. KEPT SNOWFALL IN ADVISORY CATEGORY BUT IT COULD BE CLOSE
OVER NE OH AND NW PA. THE CRITERIA FOR A WINTER WEATHER WARNING IS
6 INCHES IN 12 HOURS AND 8 INCHES IN 24 HOURS. IT IS POSSIBLE THAT
THE SNOWFALL COULD SOME 7 OR 8 INCH AMOUNTS COULD OCCUR BUT IT
WOULD OCCUR IN MORE THAN 12 HOURS...THUS THE REASONING FOR THE
ADVISORY. TEMPERATURES MAY BE STEADY OR EVEN RISE A BIT DURING THE
NIGHT.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
THE SYNOPTIC SNOW WILL BE ENDING FROM THE WEST ON MONDAY...SOME QUESTION
HOW QUICKLY THAT WILL HAPPEN. THE FLOW IN THE AFTERNOON BECOMES
WEST FOR A FEW HOURS AND THAT CONCERNS ME WHETHER THAT COULD
ENHANCE THE SNOWFALL IN THE SNOW BELT AREAS AND THEN THE FLOW
BECOMES SOUTHWEST. MANY OF THE MODELS TRY TO KEEP THE BANDS OF
LAKE EFFECT SNOW JUST OFF SHORE OR ONLY BRUSHING ERIE COUNTY
PA...THAT IS THE REASON FOR ONLY WARNING A PORTION OF THE
LAKESHORE INCLUDING THE NORTHERN HALF OF ASHTABULA COUNTY. THE
FLOW BECOMES SOUTHWEST BY DAYBREAK WEDNESDAY. ANOTHER FRONT MOVES
THROUGH ON WEDNESDAY CAUSING MORE SNOW SHOWERS. ANOTHER LAKE
EFFECT WATCH MAY BE NEEDED FOR THE SNOW BELT. ALL AREAS MAY HAVE A
THREAT OF SNOW SHOWERS FROM THIS FRONT.
THUNDERSNOW IS LIKELY IN THE SNOW BANDS MONDAY NIGHT THROUGH
TUESDAY NIGHT. IT WILL ALSO BE WINDY CAUSING NEAR BLIZZARD CONDITIONS.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL BE BUILDING INTO THE OHIO VALLEY THURSDAY
THROUGH FRIDAY AND THAT MEANS MORE LAKE EFFECT. THE MOISTURE WILL
BE DECREASING SO THE AMOUNTS WILL HAVE TO BE MONITORED. THE LAKE
AND 850 MB TEMPERATURE DIFFERENCE WILL BE OVER 26C AT FIRST AND
THEN START WARMING.
HIGH PRESSURE WILL BUILD EAST ACROSS THE AREA ON SATURDAY AS
UPPER LEVEL BROAD RIDGE TRIES TO WORK ITS WAY EAST. THIS WILL
CHANGE THE OVERALL WEATHER PATTERN GOING INTO THE THANKSGIVING DAY
WEEK. AS THE HIGH PRESSURE CENTER MOVES TO THE EAST COAST...A
RETURN SOUTHERLY FLOW WILL DEVELOP AND HENCE A RETURN TO SOME
FAIRLY STRONG WARM AIR ADVECTION. A STORM SYSTEM WILL TAKE A TRACK
UP THROUGH THE OHIO VALLEY AND BRING WITH IT SOME MOISTURE AND A
THREAT FOR RAIN TO THE AREA ESPECIALLY BY SUNDAY.
AS MENTIONED ABOVE...WARM AIR ADVECTION TAKES PLACE AND COULD SEND
TEMPERATURES BACK WELL INTO THE 40S OVER THE WEEKEND. LOWS SHOULD BE
GENERALLY IN THE 30S AS WELL.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
WIDESPREAD IFR TONIGHT WITH ACCUMULATING SNOW. PRECIPITATION
WORKING IN FROM THE SOUTHWEST THIS EVENING...MOISTENING THE
ATMOSPHERIC COLUMN. CONDITIONS DETERIORATE QUICKLY TO IFR AND LIFR
SHORTLY AFTER THE SNOW BEGINS. SOMEWHAT STEADY STATE SNOW FOR THE
NIGHT ALTHOUGH COULD GET A HEAVIER PERIOD TOWARD MORNING AS LOW
PRESSURE MOVES UP ACROSS WESTERN PA. TEMPERATURES WILL BE NEAR
FREEZING FOR CAK/YNG/ERI...OTHERS ARE EXPECTED TO STAY BELOW 32
FOR THE NIGHT. SNOW TAPERS/PULLS AWAY DURING THE MORNING HOURS FOR
MOST...EARLY AFTERNOON ACROSS THE EAST. SOME CEILING IMPROVEMENT
EXPECTED AT THE SAME TIME. WHILE WINDS WILL BE LIGHT/VARIABLE TO
NEAR CALM FOR ALL OF TONIGHT...AS SNOW ENDS WEST WINDS WILL PICK
UP. GUSTS TO 25 KNOTS POSSIBLE. FOR THE EXTENDED CLE TAF...THESE
GUSTS EXPECTED TO CONTINUE AFTER DARK MONDAY.
.OUTLOOK...NON VFR CONDITIONS PROBABLE IN LAKE EFFECT SNOW SHOWERS
LATE MONDAY THROUGH TUESDAY NIGHT MAINLY EAST OF CLEVELAND.
THUNDERSNOW POSSIBLE. AREAS OF NON-VFR AGAIN WEDNESDAY IN LIGHT
SYNOPTIC SNOW. MORE LAKE EFFECT POSSIBLE FOR THURSDAY CLEVELAND
EAST.
&&
.MARINE...
GALES OF NOVEMBER COULD POSSIBLY BE RAGING STARTING MONDAY EVENING
THROUGH TUESDAY. WINDS WILL BE OUT OF THE WEST AFTER THE COLD FRONT
PASSES THROUGH AND WINDS ARE EXPECTED TO INCREASE TO 35 KNOT GALES.
THEREFORE WILL GO AHEAD AND HOIST THE GALE WATCH AT THIS TIME. WINDS
DIMINISH AND BECOME MORE SOUTHERLY ON WEDNESDAY AHEAD OF THE NEXT
ARCTIC COLD FRONT THAT WILL MOVE THROUGH THE AREA EARLY THURSDAY
MORNING. WINDS KICK AROUND TO WEST SOUTHWEST AGAIN ON THURSDAY BUT
AT THIS TIME ARE EXPECTED TO REMAIN BELOW GALE FORCE. WINDS WILL
DIMINISH EVEN FURTHER BY FRIDAY AS HIGH PRESSURE BEGINS TO BUILD IN.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...LAKE EFFECT SNOW WATCH FROM MONDAY AFTERNOON THROUGH WEDNESDAY
MORNING FOR OHZ012-014-089.
WINTER WEATHER ADVISORY UNTIL 3 PM EST MONDAY FOR OHZ011>014-
020>023-031>033-038-089.
WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR OHZ006>010-
017>019-027>030-036-037-047.
PA...LAKE EFFECT SNOW WATCH FROM MONDAY AFTERNOON THROUGH WEDNESDAY
MORNING FOR PAZ001-002.
WINTER WEATHER ADVISORY UNTIL 3 PM EST MONDAY FOR PAZ001>003.
MARINE...GALE WATCH FROM MONDAY EVENING THROUGH TUESDAY EVENING FOR
LEZ061-142>149-162>169.
&&
$$
SYNOPSIS...KIELTYKA
NEAR TERM...KIELTYKA/TK
SHORT TERM...KIELTYKA
LONG TERM...LOMBARDY
AVIATION...OUDEMAN
MARINE...LOMBARDY
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
943 PM EST SUN NOV 16 2014
.SYNOPSIS...
A DEEP TROUGH ALOFT AND AN ARCTIC COLD FRONT WILL SWEEP ACROSS
THE AREA MONDAY. UNSEASONABLY COLD AIR WILL MOVE IN MONDAY NIGHT
AND TUESDAY AND THEN ANOTHER TROUGH WILL BE IN THE AREA FOR THE
END OF THE WORK WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
UPDATE...NO MAJOR CHANGES. DID ADJUST POPS DOWN NORTHWEST TO
REFLECT A LUL IN PRECIP AS FIRST WAVE MOVES NORTHEAST OF THE
AFTER TOWARDS OR JUST AFTER MIDNIGHT. DRYING ALREADY SHOWING UP IN
PORTIONS OF NORTHERN AND WRN INDIANA. HRRR HOWEVER DOES SHOW AT
LEAST LIGHT SNOW RETURNING BEFORE DAYBREAK BEFORE FINALLY ENDING
MONDAY MORNING. ALL ELSE ON TRACK FOR NOW.
ORIGINAL...THE SNOW WILL BE DEVELOPING SOMEWHAT QUICKLY EARLY
TONIGHT. ON THE EDGE WHETHER SOME MIX PRECIPITATION WILL OCCUR.
THIS MENTION A MIX OVER THE SOUTHERN COUNTIES BUT DID NOT MENTION
FREEZING RAIN. THE SNOWFALL AMOUNTS OF VERY TRICKY. PLENTY OF
OMEGA AND THE RIGHT REAR QUAD OF THE JET WILL HELP THINGS. KEPT
SNOWFALL IN ADVISORY CATEGORY BUT IT COULD BE CLOSE OVER NE OH AND
NW PA. THE CRITERIA FOR A WINTER WEATHER ADVISORY IS 6 INCHES IN
12 HOURS AND 8 INCHES IN 24 HOURS. IT IS POSSIBLE THAT THE
SNOWFALL COULD SOME 7 OR 8 INCH AMOUNTS COULD OCCUR BUT IT WOULD
BE IN OVER 12 HOURS...THUS THE REASONING FOR THE ADVISORY.
TEMPERATURES MAY BE STEADY OR EVEN RISE A BIT DURING THE NIGHT.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
THE SYNOPTIC SNOW WILL BE ENDING FROM THE WEST ON MONDAY...SOME QUESTION
HOW QUICKLY THAT WILL HAPPEN. THE FLOW IN THE AFTERNOON BECOMES
WEST FOR A FEW HOURS AND THAT CONCERNS ME WHETHER THAT COULD
ENHANCE THE SNOWFALL IN THE SNOW BELT AREAS AND THEN THE FLOW
BECOMES SOUTHWEST. MANY OF THE MODELS TRY TO KEEP THE BANDS OF
LAKE EFFECT SNOW JUST OFF SHORE OR ONLY BRUSHING ERIE COUNTY
PA...THAT IS THE REASON FOR ONLY WARNING A PORTION OF THE
LAKESHORE INCLUDING THE NORTHERN HALF OF ASHTABULA COUNTY. THE
FLOW BECOMES SOUTHWEST BY DAYBREAK WEDNESDAY. ANOTHER FRONT MOVES
THROUGH ON WEDNESDAY CAUSING MORE SNOW SHOWERS. ANOTHER LAKE
EFFECT WATCH MAY BE NEEDED FOR THE SNOW BELT. ALL AREAS MAY HAVE A
THREAT OF SNOW SHOWERS FROM THIS FRONT.
THUNDERSNOW IS LIKELY IN THE SNOW BANDS MONDAY NIGHT THROUGH
TUESDAY NIGHT. IT WILL ALSO BE WINDY CAUSING NEAR BLIZZARD CONDITIONS.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL BE BUILDING INTO THE OHIO VALLEY THURSDAY
THROUGH FRIDAY AND THAT MEANS MORE LAKE EFFECT. THE MOISTURE WILL
BE DECREASING SO THE AMOUNTS WILL HAVE TO BE MONITORED. THE LAKE
AND 850 MB TEMPERATURE DIFFERENCE WILL BE OVER 26C AT FIRST AND
THEN START WARMING.
HIGH PRESSURE WILL BUILD EAST ACROSS THE AREA ON SATURDAY AS
UPPER LEVEL BROAD RIDGE TRIES TO WORK ITS WAY EAST. THIS WILL
CHANGE THE OVERALL WEATHER PATTERN GOING INTO THE THANKSGIVING DAY
WEEK. AS THE HIGH PRESSURE CENTER MOVES TO THE EAST COAST...A
RETURN SOUTHERLY FLOW WILL DEVELOP AND HENCE A RETURN TO SOME
FAIRLY STRONG WARM AIR ADVECTION. A STORM SYSTEM WILL TAKE A TRACK
UP THROUGH THE OHIO VALLEY AND BRING WITH IT SOME MOISTURE AND A
THREAT FOR RAIN TO THE AREA ESPECIALLY BY SUNDAY.
AS MENTIONED ABOVE...WARM AIR ADVECTION TAKES PLACE AND COULD SEND
TEMPERATURES BACK WELL INTO THE 40S OVER THE WEEKEND. LOWS SHOULD BE
GENERALLY IN THE 30S AS WELL.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
WIDESPREAD IFR TONIGHT WITH ACCUMULATING SNOW. PRECIPITATION
WORKING IN FROM THE SOUTHWEST THIS EVENING...MOISTENING THE
ATMOSPHERIC COLUMN. CONDITIONS DETERIORATE QUICKLY TO IFR AND LIFR
SHORTLY AFTER THE SNOW BEGINS. SOMEWHAT STEADY STATE SNOW FOR THE
NIGHT ALTHOUGH COULD GET A HEAVIER PERIOD TOWARD MORNING AS LOW
PRESSURE MOVES UP ACROSS WESTERN PA. TEMPERATURES WILL BE NEAR
FREEZING FOR CAK/YNG/ERI...OTHERS ARE EXPECTED TO STAY BELOW 32
FOR THE NIGHT. SNOW TAPERS/PULLS AWAY DURING THE MORNING HOURS FOR
MOST...EARLY AFTERNOON ACROSS THE EAST. SOME CEILING IMPROVEMENT
EXPECTED AT THE SAME TIME. WHILE WINDS WILL BE LIGHT/VARIABLE TO
NEAR CALM FOR ALL OF TONIGHT...AS SNOW ENDS WEST WINDS WILL PICK
UP. GUSTS TO 25 KNOTS POSSIBLE. FOR THE EXTENDED CLE TAF...THESE
GUSTS EXPECTED TO CONTINUE AFTER DARK MONDAY.
.OUTLOOK...NON VFR CONDITIONS PROBABLE IN LAKE EFFECT SNOW SHOWERS
LATE MONDAY THROUGH TUESDAY NIGHT MAINLY EAST OF CLEVELAND.
THUNDERSNOW POSSIBLE. AREAS OF NON-VFR AGAIN WEDNESDAY IN LIGHT
SYNOPTIC SNOW. MORE LAKE EFFECT POSSIBLE FOR THURSDAY CLEVELAND
EAST.
&&
.MARINE...
GALES OF NOVEMBER COULD POSSIBLY BE RAGING STARTING MONDAY EVENING
THROUGH TUESDAY. WINDS WILL BE OUT OF THE WEST AFTER THE COLD FRONT
PASSES THROUGH AND WINDS ARE EXPECTED TO INCREASE TO 35 KNOT GALES.
THEREFORE WILL GO AHEAD AND HOIST THE GALE WATCH AT THIS TIME. WINDS
DIMINISH AND BECOME MORE SOUTHERLY ON WEDNESDAY AHEAD OF THE NEXT
ARCTIC COLD FRONT THAT WILL MOVE THROUGH THE AREA EARLY THURSDAY
MORNING. WINDS KICK AROUND TO WEST SOUTHWEST AGAIN ON THURSDAY BUT
AT THIS TIME ARE EXPECTED TO REMAIN BELOW GALE FORCE. WINDS WILL
DIMINISH EVEN FURTHER BY FRIDAY AS HIGH PRESSURE BEGINS TO BUILD IN.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...LAKE EFFECT SNOW WATCH FROM MONDAY AFTERNOON THROUGH WEDNESDAY
MORNING FOR OHZ012-014-089.
WINTER WEATHER ADVISORY UNTIL 3 PM EST MONDAY FOR OHZ011>014-
020>023-031>033-038-089.
WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR OHZ006>010-
017>019-027>030-036-037-047.
PA...LAKE EFFECT SNOW WATCH FROM MONDAY AFTERNOON THROUGH WEDNESDAY
MORNING FOR PAZ001-002.
WINTER WEATHER ADVISORY UNTIL 3 PM EST MONDAY FOR PAZ001>003.
MARINE...GALE WATCH FROM MONDAY EVENING THROUGH TUESDAY EVENING FOR
LEZ061-142>149-162>169.
&&
$$
SYNOPSIS...KIELTYKA
NEAR TERM...KIELTYKA/TK
SHORT TERM...KIELTYKA
LONG TERM...LOMBARDY
AVIATION...OUDEMAN
MARINE...LOMBARDY
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
846 AM EST SAT NOV 15 2014
.SYNOPSIS...
HIGH PRESSURE LINGERS TODAY. NEXT SYSTEM WITH DEEPER MOISTURE
SUNDAY NIGHT INTO MONDAY. REINFORCING COLD AIR ARRIVES MONDAY
NIGHT INTO TUESDAY. COLDEST DAY TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
845 AM UPDATE...NO MAJOR CHANGES NEEDED. DID HIT RECORD OR NEAR
RECORD LOWS FOR MUCH OF THE AREA THIS MORNING.
PREVIOUS DISCUSSION BELOW...
STRATUS HANGING TOUGH OVER THE N MOUNTAINS ATTM WHICH IS KEEPING
TEMPS UP AT EKN COMPARED A HAIR. EXPECT THESE CLOUDS TO DISSIPATE
PER HRRR OVER THE NEXT SEVERAL HRS. ELSEWHERE...QUITE COLD WITH
TEMPS RUNNING A BIT BLOW FCST CURVE IN THE OUTLYING AREAS.
ADJUSTED HOURLY TEMPS AND MINT GRID DOWN A FEW
DEGREES...ESPECIALLY AWAY FROM URBAN CENTERS. MID TEENS LOOK LIKE
A GOOD BET ACROSS THESE LOCATIONS ACROSS THE LOWLANDS. IF THE
CLOUDS OVER THE MOUNTAINS CAN CLEAR IN TIME...THEN SOME HIGH
SINGLE NUMBERS ARE POSSIBLE OVER THE HIGH RIDGES. SNOWSHOE
CURRENTLY SITTING AT 11F.
AS FOR TODAY...THE SUN WILL FINALLY MAKE AN APPEARANCE...ALBEIT
WITH A SHORT STAY. SOME CIRRUS WILL STREAK IN DURING THE FIRST
HALF OF TODAY...FOLLOWED BY INCREASE IN MID LEVEL CLOUDS
ASSOCIATED WAA ALOFT LATE IN THE AFTERNOON AND EARLY EVENING /FROM
SW TO NE/. H85 TEMPS WILL MODERATE BY ALMOST 10 DEGREES TODAY.
STILL...WITH H925 TEMPS STILL ON THE COOL SIDE...FELT ROLLING WITH
COOLER GUIDANCE /A LA LOCAL IN HOUSE MOS/ WAS THE BEST OPTION. AS
SUCH...HAVE SOME MID 30S FOR THE LOWLANDS WITH LOWER 30S FOR THE
HIGH TERRAIN. BIGGEST IMPROVEMENT IN TEMPS COMPARED TO YESTERDAY
WILL BE FELT IN THE HIGHER ELEVATIONS WHERE SNOWSHOE SHOULD MAKE A
RUN TOWARD UPPER 20S LATE IN THE DAY VERSUS LOW TEENS OBSERVED YESTERDAY.
A MID LEVEL DISTURBANCE WILL RACE THROUGH THE REGION TONIGHT.
HOWEVER...WITH LITTLE FANFARE OTHER THAN THE INCREASE IN MIDDLE
LEVEL CLOUDS. THE WAA ALOFT CONTINUES THOUGH...SO HAVE HIGHEST
RIDGES HOLDING NEAR STEADY IF NOT RISING TOWARD MORNING WITH
GENERALLY MID 20S IN THE LOWLANDS.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
A WAVE MOVING ACROSS SATURDAY NIGHT INTO SUNDAY SUFFERS FROM LACK OF
LOW LEVEL MOISTURE. SHOULD SEE LOTS OF VIRGA...BUT QUESTIONABLE HOW
MUCH MAKES IT TO THE GROUND. WILL KEEP POPS IN THE SLIGHT
CHANCE/CHANCE CATEGORIES...SLOWING INCREASING AS THE COLUMN TRIES TO
SATURATE.
MAIN SYSTEM OF INTEREST ARRIVES SUNDAY NIGHT AND CONTINUES INTO
MONDAY. SREF/NAM/ECMWF ARE THE WARMEST OF THE MODELS...WITH THE GFS
AND CANADIAN ON THE COOLER SIDE. WILL RUN IN BETWEEN THE 2 CAMPS FOR
NOW...KEEPING A BAND OF PRECIPITATION IN THE MIDDLE THAT COULD BE
EITHER RAIN OR SNOW. THIS BASICALLY KEEPS MOST OF WV AND VA AS
RAIN...WITH A TRANSITION ZONE ACROSS NORTHEAST KY/SOUTHEAST OH AND
FAR NW WV. CENTRAL OH HAS THE BEST CHANCE OF BEING ALL SNOW.
THE TIMING OF THE TRANSITION TO SNOW IS ALSO UP FOR DEBATE ON MONDAY
WITH TIMING DIFFERENCES BETWEEN THE MODELS. WILL GO BELOW MOS
GUIDANCE OF HIGHS ON MONDAY DUE TO FALLING PRECIPITATION.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
THE SUPPORT FROM THE STRENGTHENING 250 MB JET SHOULD BE TO OUR EAST
BY MONDAY EVENING...WITH THE REINFORCING COLD ARCTIC AIR BLOWING
IN.
LIKE YESTERDAY AND THE DAY BEFORE THAT...WE WILL CONTINUE TO HOLD
ONTO TO HIGHER POPS LONGER IN SOME ACCUMULATING SNOW SHOWERS MONDAY
EVENING THAN MODEL GUIDANCE....AS DEW POINTS LOWER IN THE COLD AIR
ADVECTION.
DRIER ARCTIC AIR TAKES CONTROL FOR TUESDAY WITH LOW DEW POINTS. SO
DESPITE THE 850 MB THERMAL TROF...DO NOT WANT TO BE AS PESSIMISTIC
AS WE USUALLY ARE ON CLOUDS IN THE LOW LEVEL THERMAL TROF.
YET...STILL LEFT SOME FLAKES IN THE AIR WELL THROUGH TUESDAY NIGHT
FOR THE MOUNTAIN COUNTIES.
COLDEST DAY MAXIMUM READINGS SHOULD BE TUESDAY. MOST LOWLAND
READINGS IN THE 20S FOR MAXIMUM. OUR SMALL AREA AOA 4000 FEET SHOULD
REMAIN IN SINGLE DIGITS DURING THE DAY ON TUESDAY.
AN IDEAL CLEAR/CALM NIGHT MAY BE HARD TO FIND...SINCE HIGH PRESSURE
CENTER NOT DIRECTLY OVER US. BUT WINDS SHOULD DIMINISH TUESDAY
NIGHT. SO COLDEST TEMPERATURES FOR LOWLANDS LIKELY TUESDAY
NIGHT/EARLY WEDNESDAY.
CONTINUED DRY WEDNESDAY INTO THURSDAY.
WARM AIR ADVECTION MOISTURE INCREASES THURSDAY NIGHT INTO FRIDAY.
WILL HAVE CHANCE POPS SPREADING SW TO NE OVERNIGHT THURSDAY NIGHT
INTO FRIDAY.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD EXCEPT FOR SOME
LINGERING MVFR CIGS OVER KEKN EARLY THIS MORNING. AN INCREASE IN
HIGH AND MIDDLE LEVEL CLOUDS CAN BE EXPECTED AS THE DAY
PROGRESSES. THIS TREND CONTINUES TONIGHT WITH PASSAGE OF AN UPPER
LEVEL DISTURBANCE.
FLOW SURFACE AND ALOFT WILL BE LIGHT TODAY COURTESY OF HIGH
PRESSURE. FLOW ALOFT INCREASES OUT OF SW 20 TO 25 KTS TONIGHT BUT
SURFACE WINDS ACROSS TAF SITES WILL REMAIN LIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SUNDAY...
FORECAST CONFIDENCE: HIGH
ALTERNATE SCENARIOS: NONE
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EST 1HRLY 09 10 11 12 13 14 15 16 17 18 19 20
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z SUNDAY...
IFR POSSIBLE SUNDAY NIGHT INTO TUESDAY IN PRECIPITATION AND
CLOUDS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/RPY/30
NEAR TERM...SL/30
SHORT TERM...RPY
LONG TERM...KTB
AVIATION...30
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
543 AM EST SAT NOV 15 2014
.SYNOPSIS...
HIGH PRESSURE LINGERS TODAY. NEXT SYSTEM WITH DEEPER MOISTURE
SUNDAY NIGHT INTO MONDAY. REINFORCING COLD AIR ARRIVES MONDAY
NIGHT INTO TUESDAY. COLDEST DAY TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
640 AM UPDATE...
NO CHANGES ATTM. LOWEST TEMP I COULD FIND AT THIS HOUR WAS AN
UNOFFICIAL OBSERVATION OF 8 DEGREES UP A HOLLOW NEAR TOWN OF BOLT
IN SW RALEIGH COUNTY. BRRR.
PREVIOUS DISCUSSION BELOW...
STRATUS HANGING TOUGH OVER THE N MOUNTAINS ATTM WHICH IS KEEPING
TEMPS UP AT EKN COMPARED A HAIR. EXPECT THESE CLOUDS TO DISSIPATE
PER HRRR OVER THE NEXT SEVERAL HRS. ELSEWHERE...QUITE COLD WITH
TEMPS RUNNING A BIT BLOW FCST CURVE IN THE OUTLYING AREAS.
ADJUSTED HOURLY TEMPS AND MINT GRID DOWN A FEW
DEGREES...ESPECIALLY AWAY FROM URBAN CENTERS. MID TEENS LOOK LIKE
A GOOD BET ACROSS THESE LOCATIONS ACROSS THE LOWLANDS. IF THE
CLOUDS OVER THE MOUNTAINS CAN CLEAR IN TIME...THEN SOME HIGH
SINGLE NUMBERS ARE POSSIBLE OVER THE HIGH RIDGES. SNOWSHOE
CURRENTLY SITTING AT 11F.
AS FOR TODAY...THE SUN WILL FINALLY MAKE AN APPEARANCE...ALBEIT
WITH A SHORT STAY. SOME CIRRUS WILL STREAK IN DURING THE FIRST
HALF OF TODAY...FOLLOWED BY INCREASE IN MID LEVEL CLOUDS
ASSOCIATED WAA ALOFT LATE IN THE AFTERNOON AND EARLY EVENING /FROM
SW TO NE/. H85 TEMPS WILL MODERATE BY ALMOST 10 DEGREES TODAY.
STILL...WITH H925 TEMPS STILL ON THE COOL SIDE...FELT ROLLING WITH
COOLER GUIDANCE /A LA LOCAL IN HOUSE MOS/ WAS THE BEST OPTION. AS
SUCH...HAVE SOME MID 30S FOR THE LOWLANDS WITH LOWER 30S FOR THE
HIGH TERRAIN. BIGGEST IMPROVEMENT IN TEMPS COMPARED TO YESTERDAY
WILL BE FELT IN THE HIGHER ELEVATIONS WHERE SNOWSHOE SHOULD MAKE A
RUN TOWARD UPPER 20S LATE IN THE DAY VERSUS LOW TEENS OBSERVED YESTERDAY.
A MID LEVEL DISTURBANCE WILL RACE THROUGH THE REGION TONIGHT.
HOWEVER...WITH LITTLE FANFARE OTHER THAN THE INCREASE IN MIDDLE
LEVEL CLOUDS. THE WAA ALOFT CONTINUES THOUGH...SO HAVE HIGHEST
RIDGES HOLDING NEAR STEADY IF NOT RISING TOWARD MORNING WITH
GENERALLY MID 20S IN THE LOWLANDS.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
A WAVE MOVING ACROSS SATURDAY NIGHT INTO SUNDAY SUFFERS FROM LACK OF
LOW LEVEL MOISTURE. SHOULD SEE LOTS OF VIRGA...BUT QUESTIONABLE HOW
MUCH MAKES IT TO THE GROUND. WILL KEEP POPS IN THE SLIGHT
CHANCE/CHANCE CATEGORIES...SLOWING INCREASING AS THE COLUMN TRIES TO
SATURATE.
MAIN SYSTEM OF INTEREST ARRIVES SUNDAY NIGHT AND CONTINUES INTO
MONDAY. SREF/NAM/ECMWF ARE THE WARMEST OF THE MODELS...WITH THE GFS
AND CANADIAN ON THE COOLER SIDE. WILL RUN IN BETWEEN THE 2 CAMPS FOR
NOW...KEEPING A BAND OF PRECIPITATION IN THE MIDDLE THAT COULD BE
EITHER RAIN OR SNOW. THIS BASICALLY KEEPS MOST OF WV AND VA AS
RAIN...WITH A TRANSITION ZONE ACROSS NORTHEAST KY/SOUTHEAST OH AND
FAR NW WV. CENTRAL OH HAS THE BEST CHANCE OF BEING ALL SNOW.
THE TIMING OF THE TRANSITION TO SNOW IS ALSO UP FOR DEBATE ON MONDAY
WITH TIMING DIFFERENCES BETWEEN THE MODELS. WILL GO BELOW MOS
GUIDANCE OF HIGHS ON MONDAY DUE TO FALLING PRECIPITATION.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
THE SUPPORT FROM THE STRENGTHENING 250 MB JET SHOULD BE TO OUR EAST
BY MONDAY EVENING...WITH THE REINFORCING COLD ARCTIC AIR BLOWING
IN.
LIKE YESTERDAY AND THE DAY BEFORE THAT...WE WILL CONTINUE TO HOLD
ONTO TO HIGHER POPS LONGER IN SOME ACCUMULATING SNOW SHOWERS MONDAY
EVENING THAN MODEL GUIDANCE....AS DEW POINTS LOWER IN THE COLD AIR
ADVECTION.
DRIER ARCTIC AIR TAKES CONTROL FOR TUESDAY WITH LOW DEW POINTS. SO
DESPITE THE 850 MB THERMAL TROF...DO NOT WANT TO BE AS PESSIMISTIC
AS WE USUALLY ARE ON CLOUDS IN THE LOW LEVEL THERMAL TROF.
YET...STILL LEFT SOME FLAKES IN THE AIR WELL THROUGH TUESDAY NIGHT
FOR THE MOUNTAIN COUNTIES.
COLDEST DAY MAXIMUM READINGS SHOULD BE TUESDAY. MOST LOWLAND
READINGS IN THE 20S FOR MAXIMUM. OUR SMALL AREA AOA 4000 FEET SHOULD
REMAIN IN SINGLE DIGITS DURING THE DAY ON TUESDAY.
AN IDEAL CLEAR/CALM NIGHT MAY BE HARD TO FIND...SINCE HIGH PRESSURE
CENTER NOT DIRECTLY OVER US. BUT WINDS SHOULD DIMINISH TUESDAY
NIGHT. SO COLDEST TEMPERATURES FOR LOWLANDS LIKELY TUESDAY
NIGHT/EARLY WEDNESDAY.
CONTINUED DRY WEDNESDAY INTO THURSDAY.
WARM AIR ADVECTION MOISTURE INCREASES THURSDAY NIGHT INTO FRIDAY.
WILL HAVE CHANCE POPS SPREADING SW TO NE OVERNIGHT THURSDAY NIGHT
INTO FRIDAY.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD EXCEPT FOR SOME
LINGERING MVFR CIGS OVER KEKN EARLY THIS MORNING. AN INCREASE IN
HIGH AND MIDDLE LEVEL CLOUDS CAN BE EXPECTED AS THE DAY
PROGRESSES. THIS TREND CONTINUES TONIGHT WITH PASSAGE OF AN UPPER
LEVEL DISTURBANCE.
FLOW SURFACE AND ALOFT WILL BE LIGHT TODAY COURTESY OF HIGH
PRESSURE. FLOW ALOFT INCREASES OUT OF SW 20 TO 25 KTS TONIGHT BUT
SURFACE WINDS ACROSS TAF SITES WILL REMAIN LIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SUNDAY...
FORECAST CONFIDENCE: HIGH
ALTERNATE SCENARIOS: NONE
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
EST 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z SUNDAY...
IFR POSSIBLE SUNDAY NIGHT INTO TUESDAY IN PRECIPITATION AND
CLOUDS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...KTB
AVIATION...30
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
346 AM EST SAT NOV 15 2014
.SYNOPSIS...
HIGH PRESSURE LINGERS TODAY. NEXT SYSTEM WITH DEEPER MOISTURE
SUNDAY NIGHT INTO MONDAY. REINFORCING COLD AIR ARRIVES MONDAY
NIGHT INTO TUESDAY. COLDEST DAY TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
STRATUS HANGING TOUGH OVER THE N MOUNTAINS ATTM WHICH IS KEEPING
TEMPS UP AT EKN COMPARED A HAIR. EXPECT THESE CLOUDS TO DISSIPATE
PER HRRR OVER THE NEXT SEVERAL HRS. ELSEWHERE...QUITE COLD WITH
TEMPS RUNNING A BIT BLOW FCST CURVE IN THE OUTLYING AREAS.
ADJUSTED HOURLY TEMPS AND MINT GRID DOWN A FEW
DEGREES...ESPECIALLY AWAY FROM URBAN CENTERS. MID TEENS LOOK LIKE
A GOOD BET ACROSS THESE LOCATIONS ACROSS THE LOWLANDS. IF THE
CLOUDS OVER THE MOUNTAINS CAN CLEAR IN TIME...THEN SOME HIGH
SINGLE NUMBERS ARE POSSIBLE OVER THE HIGH RIDGES. SNOWSHOE
CURRENTLY SITTING AT 11F.
AS FOR TODAY...THE SUN WILL FINALLY MAKE AN APPEARANCE...ALBEIT
WITH A SHORT STAY. SOME CIRRUS WILL STREAK IN DURING THE FIRST
HALF OF TODAY...FOLLOWED BY INCREASE IN MID LEVEL CLOUDS
ASSOCIATED WAA ALOFT LATE IN THE AFTERNOON AND EARLY EVENING /FROM
SW TO NE/. H85 TEMPS WILL MODERATE BY ALMOST 10 DEGREES TODAY.
STILL...WITH H925 TEMPS STILL ON THE COOL SIDE...FELT ROLLING WITH
COOLER GUIDANCE /A LA LOCAL IN HOUSE MOS/ WAS THE BEST OPTION. AS
SUCH...HAVE SOME MID 30S FOR THE LOWLANDS WITH LOWER 30S FOR THE
HIGH TERRAIN. BIGGEST IMPROVEMENT IN TEMPS COMPARED TO YESTERDAY
WILL BE FELT IN THE HIGHER ELEVATIONS WHERE SNOWSHOE SHOULD MAKE A
RUN TOWARD UPPER 20S LATE IN THE DAY VERSUS LOW TEENS OBSERVED YESTERDAY.
A MID LEVEL DISTURBANCE WILL RACE THROUGH THE REGION TONIGHT.
HOWEVER...WITH LITTLE FANFARE OTHER THAN THE INCREASE IN MIDDLE
LEVEL CLOUDS. THE WAA ALOFT CONTINUES THOUGH...SO HAVE HIGHEST
RIDGES HOLDING NEAR STEADY IF NOT RISING TOWARD MORNING WITH
GENERALLY MID 20S IN THE LOWLANDS.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
A WAVE MOVING ACROSS SATURDAY NIGHT INTO SUNDAY SUFFERS FROM LACK OF
LOW LEVEL MOISTURE. SHOULD SEE LOTS OF VIRGA...BUT QUESTIONABLE HOW
MUCH MAKES IT TO THE GROUND. WILL KEEP POPS IN THE SLIGHT
CHANCE/CHANCE CATEGORIES...SLOWING INCREASING AS THE COLUMN TRIES TO
SATURATE.
MAIN SYSTEM OF INTEREST ARRIVES SUNDAY NIGHT AND CONTINUES INTO
MONDAY. SREF/NAM/ECMWF ARE THE WARMEST OF THE MODELS...WITH THE GFS
AND CANADIAN ON THE COOLER SIDE. WILL RUN IN BETWEEN THE 2 CAMPS FOR
NOW...KEEPING A BAND OF PRECIPITATION IN THE MIDDLE THAT COULD BE
EITHER RAIN OR SNOW. THIS BASICALLY KEEPS MOST OF WV AND VA AS
RAIN...WITH A TRANSITION ZONE ACROSS NORTHEAST KY/SOUTHEAST OH AND
FAR NW WV. CENTRAL OH HAS THE BEST CHANCE OF BEING ALL SNOW.
THE TIMING OF THE TRANSITION TO SNOW IS ALSO UP FOR DEBATE ON MONDAY
WITH TIMING DIFFERENCES BETWEEN THE MODELS. WILL GO BELOW MOS
GUIDANCE OF HIGHS ON MONDAY DUE TO FALLING PRECIPITATION.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
THE SUPPORT FROM THE STRENGTHENING 250 MB JET SHOULD BE TO OUR EAST
BY MONDAY EVENING...WITH THE REINFORCING COLD ARCTIC AIR BLOWING
IN.
LIKE YESTERDAY AND THE DAY BEFORE THAT...WE WILL CONTINUE TO HOLD
ONTO TO HIGHER POPS LONGER IN SOME ACCUMULATING SNOW SHOWERS MONDAY
EVENING THAN MODEL GUIDANCE....AS DEW POINTS LOWER IN THE COLD AIR
ADVECTION.
DRIER ARCTIC AIR TAKES CONTROL FOR TUESDAY WITH LOW DEW POINTS. SO
DESPITE THE 850 MB THERMAL TROF...DO NOT WANT TO BE AS PESSIMISTIC
AS WE USUALLY ARE ON CLOUDS IN THE LOW LEVEL THERMAL TROF.
YET...STILL LEFT SOME FLAKES IN THE AIR WELL THROUGH TUESDAY NIGHT
FOR THE MOUNTAIN COUNTIES.
COLDEST DAY MAXIMUM READINGS SHOULD BE TUESDAY. MOST LOWLAND
READINGS IN THE 20S FOR MAXIMUM. OUR SMALL AREA AOA 4000 FEET SHOULD
REMAIN IN SINGLE DIGITS DURING THE DAY ON TUESDAY.
AN IDEAL CLEAR/CALM NIGHT MAY BE HARD TO FIND...SINCE HIGH PRESSURE
CENTER NOT DIRECTLY OVER US. BUT WINDS SHOULD DIMINISH TUESDAY
NIGHT. SO COLDEST TEMPERATURES FOR LOWLANDS LIKELY TUESDAY
NIGHT/EARLY WEDNESDAY.
CONTINUED DRY WEDNESDAY INTO THURSDAY.
WARM AIR ADVECTION MOISTURE INCREASES THURSDAY NIGHT INTO FRIDAY.
WILL HAVE CHANCE POPS SPREADING SW TO NE OVERNIGHT THURSDAY NIGHT
INTO FRIDAY.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD EXCEPT FOR SOME
MVFR CIGS OVER KBKW EARLY THIS MORNING. AN INCREASE IN HIGH AND
MIDDLE LEVEL CLOUDS CAN BE EXPECTED AS THE DAY PROGRESSES. THIS
TREND CONTINUES TONIGHT WITH PASSAGE OF AN UPPER LEVEL
DISTURBANCE.
FLOW SURFACE AND ALOFT WILL BE LIGHT TODAY COURTESY OF HIGH
PRESSURE. FLOW ALOFT INCREASES OUT OF SW 20 TO 25 KTS TONIGHT BUT
SURFACE WINDS ACROSS TAF SITES WILL REMAIN LIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SUNDAY...
FORECAST CONFIDENCE: HIGH
ALTERNATE SCENARIOS: NONE
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SAT 11/15/14
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z SUNDAY...
IFR POSSIBLE SUNDAY NIGHT INTO TUESDAY IN PRECIPITATION AND
CLOUDS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...KTB
AVIATION...30
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
135 AM EST SAT NOV 15 2014
.SYNOPSIS...
HIGH PRESSURE LINGERS TODAY. NEXT SYSTEM WITH DEEPER MOISTURE
SUNDAY NIGHT INTO MONDAY. REINFORCING COLD AIR ARRIVES MONDAY
NIGHT INTO TUESDAY. COLDEST DAY TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
STRATUS HANGING TOUGH OVER THE N MOUNTAINS ATTM WHICH IS KEEPING
TEMPS UP AT EKN COMPARED A HAIR. EXPECT THESE CLOUDS TO DISSIPATE
PER HRRR OVER THE NEXT SEVERAL HRS. ELSEWHERE...QUITE COLD WITH
TEMPS RUNNING A BIT BLOW FCST CURVE IN THE OUTLYING AREAS.
ADJUSTED HOURLY TEMPS AND MINT GRID DOWN A FEW
DEGREES...ESPECIALLY AWAY FROM URBAN CENTERS. MID TEENS LOOK LIKE
A GOOD BET ACROSS THESE LOCATIONS ACROSS THE LOWLANDS. IF THE
CLOUDS OVER THE MOUNTAINS CAN CLEAR IN TIME...THEN SOME HIGH
SINGLE NUMBERS ARE POSSIBLE OVER THE HIGH RIDGES. SNOWSHOE
CURRENTLY SITTING AT 11F.
AS FOR TODAY...THE SUN WILL FINALLY MAKE AN APPEARANCE...ALBEIT
WITH A SHORT STAY. SOME CIRRUS WILL STREAK IN DURING THE FIRST
HALF OF TODAY...FOLLOWED BY INCREASE IN MID LEVEL CLOUDS
ASSOCIATED WAA ALOFT LATE IN THE AFTERNOON AND EARLY EVENING /FROM
SW TO NE/. H85 TEMPS WILL MODERATE BY ALMOST 10 DEGREES TODAY.
STILL...WITH H925 TEMPS STILL ON THE COOL SIDE...FELT ROLLING WITH
COOLER GUIDANCE /A LA LOCAL IN HOUSE MOS/ WAS THE BEST OPTION. AS
SUCH...HAVE SOME MID 30S FOR THE LOWLANDS WITH LOWER 30S FOR THE
HIGH TERRAIN. BIGGEST IMPROVEMENT IN TEMPS COMPARED TO YESTERDAY
WILL BE FELT IN THE HIGHER ELEVATIONS WHERE SNOWSHOE SHOULD MAKE A
RUN TOWARD UPPER 20S LATE IN THE DAY VERSUS LOW TEENS OBSERVED YESTERDAY.
A MID LEVEL DISTURBANCE WILL RACE THROUGH THE REGION TONIGHT.
HOWEVER...WITH LITTLE FANFARE OTHER THAN THE INCREASE IN MIDDLE
LEVEL CLOUDS. THE WAA ALOFT CONTINUES THOUGH...SO HAVE HIGHEST
RIDGES HOLDING NEAR STEADY IF NOT RISING TOWARD MORNING WITH
GENERALLY MID 20S IN THE LOWLANDS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
SURFACE HIGH PRESSURE EXITING TO THE EAST AT THE START OF THE
PERIOD. MOISTURE BEGINS INCREASING SATURDAY NIGHT INTO SUNDAY...AND
AS A WEAK SHORTWAVE PASSES TO OUR NORTH WE COULD SQUEEZE OUT A
LITTLE SNOW ACROSS NW CORNER OF CWA. STILL PRETTY DRY AT THE
SURFACE...SO ONLY HAVE LOW CHANCE POPS WITH THIS. MOISTURE CONTINUES
TO INCREASE THROUGH SUNDAY. SOME UNCERTAINTY ON JUST HOW QUICKLY THE
COLUMN WILL SATURATE AND PRECIP WILL BEGIN. MODELS SEEM TO HAVE
BACKED OFF JUST A TOUCH...SO REDUCED POPS SOME SUNDAY MORNING.
POPS RAMP UP PRETTY QUICKLY AS WARM AIR ADVECTION CONTINUES MOISTURE
INFLOW AND STARTS PROVIDING LIFT. IN REALITY WILL LIKELY BE AN EVEN
TIGHTER POP GRADIENT THAN CURRENT FORECAST AS COLUMN SATURATES. WITH
THE WARM AIR ADVECTION FOLLOWED BY COLD SURGE FROM THE
WEST...ANTICIPATE A WARM WEDGE SETTING UP ACROSS THE WV LOWLANDS FOR
SUNDAY NIGHT INTO MONDAY. FARTHER WEST...NEAR THE OHIO
RIVER...COLDER AIR WILL PUSH IN CHANGING RAIN TO SNOW SUNDAY NIGHT.
MODELS IN GOOD AGREEMENT WITH JET DYNAMICS TAKING OVER SUNDAY
NIGHT...INCREASING PRECIP EFFICIENCY AS DIVERGENCE FROM A 130-150KT
JET STREAK SETS UP OVER THE OHIO RIVER VALLEY. MODELS ALSO IN GOOD
AGREEMENT ON 850MB TEMPERATURE FIELD...WITH RATHER TIGHT GRADIENT
CENTERED ROUGHLY OVER THE OHIO RIVER. THIS WILL ALLOW ACCUMULATING
SNOW FROM THE OHIO RIVER WEST...WITH MORE OF A RAIN/SNOW/SLEET MIX
EAST OF THE RIVER...AND EVEN JUST RAIN ACROSS THE SOUTHERN COAL
FIELDS INTO MONDAY AFTERNOON. WITH THE COLD AIR AND JET STREAK
LINING UP PRETTY WELL...EXPECTING A GOOD BAND OF SNOW DEVELOPING
OVER SE OHIO. HAVE GENERALLY 2-4 INCHES. ANTICIPATE A BAND OF 4 OR
MORE SOMEWHERE JUST WEST OF THE OHIO RIVER...BUT CANNOT PIN POINT
THAT THIS FAR OUT.
THAT WILL PUT US RIGHT AT THE WINTER WEATHER ADVISORY/WARNING
CRITERIA LINE WHERE EVER THAT BAND SETS UP. WILL CONTINUE MENTION OF
POSSIBLE WINTER HEADLINES IN HWO...AND HOPEFULLY THE HIGHER
RESOLUTION NEAR TERM MODELS WILL BEGIN PROVIDING USEFUL INPUT INTO
THE MOST LIKELY PLACEMENT FOR THE BAND OF HIGHER SNOW OVER THE NEXT
SEVERAL SHIFTS.
FARTHER EAST...ACROSS THE HIGHEST TERRAIN OF THE WV
MOUNTAINS...THERE COULD BE A BRIEF PERIOD OF SOME LIGHT FREEZING
RAIN AND/OR SLEET AS TEMPERATURES ALOFT WARM SUNDAY NIGHT.
AS THE COLD AIR CONTINUES TRYING TO ERODE THE WARM WEDGE MONDAY
AND THE UPPER LEVEL JET SINKS SE ACROSS FORECAST AREA...HAVE ANY
REMAINING RAIN CHANGING BACK OVER TO SNOW FROM WEST TO
EAST...BECOMING ALL SNOW BY 22Z-23Z.
BLENDED IN GFS/ECMWF INTO PREVIOUS TEMP FORECAST THROUGH SUNDAY
NIGHT...AND THEN WENT NON-DIURNAL MONDAY AS COLD AIR SURGES IN.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE SUPPORT FROM THE STRENGTHENING 250 MB JET SHOULD BE TO OUR EAST
BY MONDAY EVENING...WITH THE REINFORCING COLD ARCTIC AIR BLOWING
IN.
LIKE YESTERDAY AND THE DAY BEFORE THAT...WE WILL CONTINUE TO HOLD
ONTO TO HIGHER POPS LONGER IN SOME ACCUMULATING SNOW SHOWERS MONDAY
EVENING THAN MODEL GUIDANCE....AS DEW POINTS LOWER IN THE COLD AIR
ADVECTION.
DRIER ARCTIC AIR TAKES CONTROL FOR TUESDAY WITH LOW DEW POINTS. SO
DESPITE THE 850 MB THERMAL TROF...DO NOT WANT TO BE AS PESSIMISTIC
AS WE USUALLY ARE ON CLOUDS IN THE LOW LEVEL THERMAL TROF.
YET...STILL LEFT SOME FLAKES IN THE AIR WELL THROUGH TUESDAY NIGHT
FOR THE MOUNTAIN COUNTIES.
COLDEST DAY MAXIMUM READINGS SHOULD BE TUESDAY. MOST LOWLAND
READINGS IN THE 20S FOR MAXIMUM. OUR SMALL AREA AOA 4000 FEET SHOULD
REMAIN IN SINGLE DIGITS DURING THE DAY ON TUESDAY.
AN IDEAL CLEAR/CALM NIGHT MAY BE HARD TO FIND...SINCE HIGH PRESSURE
CENTER NOT DIRECTLY OVER US. BUT WINDS SHOULD DIMINISH TUESDAY
NIGHT. SO COLDEST TEMPERATURES FOR LOWLANDS LIKELY TUESDAY
NIGHT/EARLY WEDNESDAY.
CONTINUED DRY WEDNESDAY INTO THURSDAY.
WARM AIR ADVECTION MOISTURE INCREASES THURSDAY NIGHT INTO FRIDAY.
WILL HAVE CHANCE POPS SPREADING SW TO NE OVERNIGHT THURSDAY NIGHT
INTO FRIDAY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD EXCEPT FOR SOME
MVFR CIGS OVER KBKW EARLY THIS MORNING. AN INCREASE IN HIGH AND
MIDDLE LEVEL CLOUDS CAN BE EXPECTED AS THE DAY PROGRESSES. THIS
TREND CONTINUES TONIGHT WITH PASSAGE OF AN UPPER LEVEL
DISTURBANCE.
FLOW SURFACE AND ALOFT WILL BE LIGHT TODAY COURTESY OF HIGH
PRESSURE. FLOW ALOFT INCREASES OUT OF SW 20 TO 25 KTS TONIGHT BUT
SURFACE WINDS ACROSS TAF SITES WILL REMAIN LIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SUNDAY...
FORECAST CONFIDENCE: HIGH
ALTERNATE SCENARIOS: NONE
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SAT 11/15/14
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z SUNDAY...
IFR POSSIBLE SUNDAY NIGHT INTO TUESDAY IN PRECIPITATION AND
CLOUDS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/RPY/30
NEAR TERM...30
SHORT TERM...MZ
LONG TERM...KTB
AVIATION...30
AREA FORECAST DISCUSSION
NWS NORMAN OK
1054 PM CST FRI NOV 14 2014
.DISCUSSION...
AVIATION DISCUSSION FOR THE 06Z TAFS IS BELOW.
&&
.AVIATION...
OVERALL...VFR CONDITIONS ARE EXPECTED TO CONTINUE.
A LIGHT WINTRY MIX OF PRECIPITATION IS POSSIBLE NEARLY ANYWHERE
THROUGH 18Z. CONFIDENCE OF PRECIPITATION OCCURRENCE REMAINS TOO
LOW TO MENTION AT THIS TIME AS MOST PRECIPITATION WILL LIKELY
STAY NORTH OF THE OKLAHOMA KANSAS STATELINE.
THERE IS AN OUTSIDE CHANCE FOR MVFR CEILINGS TO DEVELOP
ACROSS THE AREA AFTER 09Z...BUT DID NOT MENTION DUE TO LOW
CONFIDENCE.
SOUTH TO SOUTHEAST WINDS WILL BECOME GUSTY AT MANY SITES
09-16Z...THEN DIMINISH 20-24Z. A COLD FRONT WILL BRING A WIND
SHIFT TO THE NORTH NEAR KWWR AND KGAG AROUND 21Z...AND TO OTHER
SITES 22-02Z.
MBS
&&
.PREV DISCUSSION... /ISSUED 719 PM CST FRI NOV 14 2014/
UPDATE...
ADJUSTED PRECIPITATION TYPE ACROSS NORTHERN OKLAHOMA AFTER
MIDNIGHT TONIGHT THROUGH EARLY SATURDAY AFTERNOON TO INCLUDE
SLEET.
DISCUSSION...
A LIGHT WINTRY MIX OF MAINLY LIGHT SLEET AND LIGHT SNOW
IS POSSIBLE AFTER MIDNIGHT TONIGHT THROUGH 3 PM SATURDAY
ACROSS NORTHERN OKLAHOMA.
LATEST HRRR RUNS HAVE BEEN DEPICTING LIGHT PRECIPITATION
DEVELOPING AS LIFT INCREASES IN NORTHWEST OKLAHOMA MIDNIGHT TO
4 AM TONIGHT...THEN SPREADING EAST...AFFECTING AREAS NORTH OF A
GAGE TO STILLWATER LINE. FORECAST PRECIPITATION CHANCES ARE IN
GOOD SHAPE AND WERE NOT ALTERED.
BASED ON THE LATEST 00Z NEARBY UPPER AIR SOUNDINGS AND TOP DOWN
SOUNDING METHODOLOGY...BELIEVE ANY PRECIPITATION REACHING THE
GROUND WOULD MAINLY BE LIGHT SLEET AS PRECIPITATION ALOFT WOULD
PARTIALLY OR COMPLETELY MELT WITH A 720-800 MB WARM NOSE OF +1 TO
+6C THEN REFREEZE 800-850 MB WITH TEMPERATURES AROUND -9C.
LIGHT SNOW WOULD BE POSSIBLE IF PRECIPITATION INTENSITY BECOMES
HEAVY ENOUGH TO ALLOW EVAPORATIONAL COOLING TO ERODE THE MID
LEVEL WARM NOSE. LATEST RAP13 RUNS HINT THAT THIS COULD OCCUR
NORTH OF AN ALVA TO STILLWATER LINE AFTER 4 AM TONIGHT.
REGARDLESS OF PRECIPITATION TYPE...ANY PRECIPITATION AMOUNTS
APPEAR TO BE LIGHT IN NORTHERN OKLAHOMA WITH THE HEAVIER AMOUNTS
FARTHER NORTH ACROSS NORTHERN KANSAS LATE TONIGHT INTO SATURDAY.
COULD NOT COMPLETELY RULE OUT A DUSTING OF SLEET OR SNOW
ACCUMULATIONS MIDNIGHT TONIGHT TO 3 PM SATURDAY OVER NORTHERN
OKLAHOMA...BUT THINK IMPACTS WILL BE MINIMAL DUE TO THE LIGHT
NATURE OF PRECIPITATION AND LACK OF SIGNIFICANT NEARBY MOISTURE.
HOWEVER...WITH SURFACE TEMPERATURES BELOW FREEZING...A FEW SLICK
SPOTS COULD DEVELOP.
WILL CONTINUE TO MONITOR. PRODUCTS HAVE BEEN UPDATED. NO WINTER
WEATHER ADVISORIES ARE EXPECTED TO BE ISSUED FOR TONIGHT THROUGH
SATURDAY AFTERNOON AT THIS TIME.
MBS
PREV DISCUSSION... /ISSUED 255 PM CST FRI NOV 14 2014/
DISCUSSION...
SHORT TERM...(TONIGHT-SUNDAY NIGHT)
LOW CLOUDS SHOULD CONTINUE TO ERODE THROUGH THE AFTERNOON
WHILE HIGH CLOUDS SLOWLY INCREASE. A QUICK MOVING SYSTEM WILL
APPROACH TONIGHT AND SHOULD CLEAR THE SOUTHERN PLAINS BY SATURDAY
AFTERNOON. THE OVERALL TREND WITH THIS SYSTEM...HAS BEEN BETTER
CHANCES FOR PRECIPITATION MAINLY NORTH OF OKLAHOMA. WILL KEEP LOW
CHANCES FOR LIGHT SNOW ACROSS NORTHERN OKLAHOMA FROM LATE TONIGHT
THROUGH LATE SATURDAY MORNING. A WARM NOSE BELOW 7H ACROSS
NORTHWEST OKLAHOMA MAY RESULT IN SOME SLEET OVERNIGHT.
PRECIPITATION AMOUNTS WILL BE LIGHT WITH THIS SYSTEM.
ANOTHER PUSH OF RATHER COLD AIR WILL BEGIN TO ENTER NORTHWEST
OKLAHOMA LATE SATURDAY AFTERNOON AND EVENING. GUSTY NORTHERLY
WINDS CAN BE EXPECTED ACROSS MOST OF OKLAHOMA BY EARLY/MID
SUNDAY MORNING. AN APPROACHING WAVE WILL BRING A DECENT CHANCE
OF LIGHT SNOW SUNDAY MORNING AND AFTERNOON. MOST MODELS INDICATE
THE BEST LIFT OCCURRING ACROSS NORTHERN OKLAHOMA SUNDAY MORNING
THEN SHIFTING SOUTHWARD DURING THE AFTERNOON. A LITTLE UNSURE ON
AMOUNTS...BUT EXPECT SOME AREAS NORTH OF OF I-40 SHOULD SEE AN
INCH OF SNOW WITH 2 INCH AMOUNTS POSSIBLE. WITH THE RECENT COLD
WEATHER...ANY SNOW THAT FALLS WILL ACCUMULATE AND MAY CAUSE MINOR
TRAFFIC DELAYS.
LONG TERM...(MONDAY-THURSDAY)
A GRADUAL WARMING TREND WILL BEGIN EARLY NEXT WEEK, WITH SURFACE
WINDS BECOMING SOUTHERLY BY MIDWEEK. AN UPPER WAVE WILL MOVE
ACROSS THE AREA ON THURSDAY, BRINGING LOW POPS FOR RAIN ACROSS
SOUTHEAST OKLAHOMA. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM
APPEARS TO BE WEAK, STALLING ACROSS NORTHWEST OKLAHOMA BEFORE
LIFTING BACK TO THE NORTH.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 27 46 27 29 / 0 20 10 50
HOBART OK 28 48 27 29 / 10 10 10 40
WICHITA FALLS TX 29 53 32 33 / 0 10 10 30
GAGE OK 25 42 20 29 / 20 10 30 60
PONCA CITY OK 25 41 24 29 / 10 30 20 60
DURANT OK 28 45 34 39 / 0 10 20 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
04/17/17
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1157 PM EST FRI NOV 14 2014
.SYNOPSIS...
THE ANOMALOUS UPPER TROUGH WILL BRIEFLY LIFT OUT OVER THE WEEKEND
AS SURFACE HIGH PRESSURE SLIDES BY JUST TO THE SOUTH OF
PENNSYLVANIA. AN EVEN DEEPER TROUGH WILL FORM OVER THE GREAT
LAKES AND NORTHEAST CONUS EARLY NEXT WEEK. THIS DEEPENING TROUGH
WILL HELP TO FORM A FAST MOVING AREA OF LOW PRESSURE THAT WILL
TRACK FROM THE DEEP SOUTH TO THE SOUTHERN NEW ENGLAND COAST BY
MONDAY EVENING. THIS WEATHER FEATURE WILL BRING A LIKELIHOOD OF A
LIGHT TO MODERATE SNOWFALL MONDAY ACROSS AT LEAST THE NORTHWEST
HALF OF PENNSYLVANIA. MIXED PRECIPITATION AND RAIN ARE MOST
LIKELY OVER THE CENTRAL AND SOUTHEAST ON MONDAY.
&&
.NEAR TERM /UNTIL 7 AM SATURDAY MORNING/...
10 PM UPDATE...
SNOW SHOWERS ARE STILL MAINLY CELLULAR IN ONLY SEMI-CONCENTRATED
BANDS. CELLS MOVING VERY QUICKLY AND CIGS GET HIGH PRETTY QUICKLY
AWAY FROM THE LAKE. EVEN KERI IS HIGH-MVFR WHEN IT DOES SNOW
THERE. THUS...ACCUMS FOR THE OVERNIGHT LOOK ON TRACK. AS
EARLIER...HRRR AND RAP HANDLING THE NEAR-TERM WAGGLE TO THE SOUTH
OF THE BROAD BANDS. THEY AND THE NEWEST NAM CONTINUE TO SINK THE
BANDS SOUTHWARD FOR A FEW MORE HOURS...THEN STALL FOR A FEW HOURS
AND SHOVE THEM BACK TO THE NORTH AS THE CENTER OF THE BIG SFC HIGH
MOVES INTO THE CENTRAL APPALACHIANS.
730 PM UPDATE...
HRRR AND RUC HANDLING THE SHIFT OF THE BANDS TO THE SOUTH WITH
VEERING LOW LEVEL WINDS VERY NICELY. THE NEAR TERM PREDICTIONS
PORTRAY THE CONTINUED VEERING THROUGH MIDNIGHT OR A LITTLE
LATER...THEN A TURN AROUND AND BACKING TO A GENERALLY SWRLY FLOW
IN THE CLOUD LAYER BY SUNRISE. THUS...HAVE HIGH CONFIDENCE IN
KEEPING ALL THE WEATHER ELEMENTS VERY CLOSE TO CURRENT
PROJECTIONS. LES ADVY STILL LOOKING GOOD FOR WARREN CO.
PREV...
A PERSISTENT...COLD NORTHWESTERLY FLOW OVR THE GRT LKS WILL
CONTINUE TO PRODUCE FREQUENT SNOW SHOWERS ACROSS THE NW MTNS
AND LAUREL HIGHLANDS TONIGHT WITH ADDITIONAL LIGHT ACCUMULATIONS
OF A COATING TO ONE INCH ACROSS MANY AREAS NEAR...AND JUST TO THE
WEST OF RT 219.
HIGH RES MODELS SHOW DIRECTIONAL SHEAR IN THE LOWEST FEW KM
BECOMING BETTER ALIGNED LATE THIS AFTERNOON THROUGH MUCH OF
TONIGHT...WHICH WILL CREATE 2 OR 3...MORE ORGANIZED LES BANDS
/THAT WILL PENETRATE FURTHER INLAND THANKS TO A MEAN 20KT FLOW
FROM 300 DEG IN THE LOWEST 2 KM/.
BRIEF PERIODS OF 1/4-1/2SM SNOW WILL OCCUR WITHIN THESE BANDS.
EXTENDED THE LES ADVISORY FOR WARREN COUNTY THROUGH 12Z SATURDAY
AS THE PASSAGE OF A WEAK UPPER SHORT WAVE AND SFC TROUGH WILL LEAD
TO A BETTER UPSTREAM MOISTURE TAP OFF SOUTHERN LAKE HURON.
AREAS OF MORE SHALLOW BKN-OVC STRATO CU ACROSS THE NORTH-CENTRAL
MTNS AND CENTRAL RIDGE AND VALLEY REGION /INCLUDING THE SUSQ
VALLEY/ WILL SUPPORT MAINLY FLURRIES AN PERHAPS A BRIEF 2-3SM VSBY
SNOW SHOWER LATE TODAY AND TONIGHT WITH A FEW LOCATIONS SEEING A
POWDERY DUSTING OF SNOW.
MIN TEMPS EARLY SATURDAY WILL BE IN THE LOWER TO MID 20S...BUT THE
WEST TO NORTHWEST BREEZE WILL DECREASE TO ABOUT 6-8 KTS AFTER 02Z
SAT.
&&
.SHORT TERM /7 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
EXPECT ANY REMAINING LAKE EFFECT SNOW BANDS TO SHIFT QUICKLY NORTH
OR DISSIPATE DURING LATE MORNING/EARLY AFTERNOON HOURS AS SHEAR
WITHIN THE SFC-800 INCREASES...BEFORE THE MEAN WIND IN THIS LAYER
GRADUALLY BACKS TO THE WEST-SOUTHWEST IN THE AFTERNOON.
ACROSS THE CENTRAL AND SERN ZONES...SOME MORNING CLOUDS AND
FLURRIES WILL LIKELY YIELD TO INCREASING AMOUNT OF SUNSHINE
THROUGH THE SHALLOW STRATO CU DECK.
PARTLY TO MOSTLY CLOUDY SKIES IN THE FORM OF MAINLY ALTO CU CLOUDS
EXPECTED FOR SAT NIGHT AS A WARM FRONT LIFTS NE FROM THE OHIO
VALLEY. A BIT OF LIGHT SNOW OR FLURRIES IS POSSIBLE SAT
NIGHT/EARLY SUNDAY ACROSS THE NW HALF OF THE STATE WITH VERY MINOR
ACCUMS AT MOST.
MAX TEMPS SAT WILL BE IN THE L-M 30S ACROSS THE NRN AND WRN
MTNS...AND UPR 30S TO L40S FURTHER SE THROUGH THE SUSQ VALLEY.
LOW TEMPS AT DAYBREAK SUNDAY WILL BE IN THE M-U 20S ACROSS THE
MTNS AND 30-35 ELSEWHERE.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
COLD WEATHER PATTERN CONTINUES THROUGH NEXT WEEK...
ADVISORY LEVEL SNOW ACCUMULATION POSSIBLE ON MONDAY...
UPPER LEVEL RIDGING FROM THE NW COAST TO ALASKA WILL SUSTAIN AND
MAINTAIN A DEEP TROUGH AND UNSEASONABLY COLD AIRMASS OVER THE AREA
THROUGH MUCH OF NEXT WEEK. FORECAST CONFIDENCE REMAINS VERY HIGH
IN A PROLONGED STRETCH OF WELL-BELOW NORMAL TEMPERATURES FOR THIS
TIME OF YEAR WITH THE CORE OF THE COLD IMPACTING THE CWA TUE-WED.
MODELS CONTINUE TO SHOW A LEAD SHORTWAVE CROSSING THE ERN GREAT
LAKES ON SUNDAY...WHICH COULD SPREAD SOME LIGHT SNOW/RAIN INTO THE
WESTERN COUNTIES DURING THE DAY. RELOADING CENTRAL US TROUGH
BECOMES WELL ESTABLISHED BY 12Z MONDAY WITH CORE OF NEGATIVE
HEIGHT ANOMALIES /-3 STD/ SPREADING EWD FROM THE UPPER MIDWEST
THROUGH THE OH VALLEY.
THERE IS AN EMERGING CONSENSUS AMONG THE GLOBAL GUIDANCE IN A
BROAD AREA OF PCPN OVERSPREADING THE AREA ON MONDAY...AS MOISTURE
AND LIFT BECOME ENHANCED WITHIN THE ENTRANCE REGION OF A STRONG
UPPER JET EAST OF THE DEEP TROUGH...ALONG SHARPENING LOW LEVEL
THERMAL GRADIENT/FRONTAL AXIS MARKING LEADING EDGE OF ARCTIC
AIRMASS. FOLLOWED WPC BLEND FOR QPF AND THERMAL PROFILES WHICH
SUPPORTS POTENTIAL FOR ADVISORY LEVEL SNOW ACCUMULATIONS /2-4
INCHES/ OVER THE NW 1/2 OF THE CWA. FURTHER SOUTH/EAST...A RAIN TO
SNOW MIX TO CHANGEOVER SCENARIO SEEMS LKLY WITH LOWER ACCUMS GIVEN
INITIALLY WARM BLYR. ALTHOUGH THE PTYPE DETAILS AND SNOW ACCUMS
ARE STILL UNCERTAIN...CONFIDENCE IN WINTER WEATHER IMPACTS TO THE
MONDAY MORNING COMMUTE IS INCREASING ESPECIALLY OVER THE WRN 1/2
OF THE CWA. WILL ADD WORDING INTO THE HWO.
A FRIGID SURGE OF ARCTIC AIR WILL BLAST INTO THE REGION BEHIND
THIS SYSTEM ON TUESDAY AND PERSIST THRU THE MIDDLE OF NEXT WEEK.
MEAN 85H TEMPS ARND -15C IN BOTH THE GEFS/ECENS TRANSLATE INTO
HIGH TEMPS BELOW FREEZING FOR MOST OF CENTRAL PA TUE/WED. WIND
CHILLS IN THE LOW TEENS AND SINGLE DIGITS ARE LKLY AND MAY EVEN
DIP BELOW 0F OVER THE WRN MTNS. THE TRANSITION BACK TO A COLD
CYCLONIC NW FLOW PATTERN WILL FAVOR LAKE EFFECT AND TERRAIN
ENHANCED SNOW SHOWERS OVER THE NW MTNS WITH COLD AND DRY
CONDITIONS FROM THE CENTRAL RIDGES INTO THE LWR SUSQ VLY.
SOME MODERATION IN TEMPS MAY BE IN SIGHT BY THE END OF NEXT WEEK
AS MODELS AND ENSEMBLES SHOW THE UPSTREAM PATTERN CONFIGURATION
BREAKING DOWN.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
LITTLE CHANGE IS EXPECTED ACRS THE REGION TONIGHT AS COLD AIR
RIDING SOUTHEAST ACROSS THE RELATIVELY WARMER WATERS OF THE GREAT
LAKES IS LIFTED OVER THE HIGHER TERRAIN IN WESTERN PA.
THE BIGGEST AVIATION CONCERN TONIGHT WILL BE THE LAKE ENHANCED
SNOW SHOWERS ACROSS THE NORTHWEST MOUNTAINS. IT IS NOT PERSISTENT
ENOUGH TO ALLOW FOR CIGS AND VSBYS TO REMAIN IFR...BUT CONDITIONS
WILL DROP DOWN TO IFR BETWEEN 04Z TO 09Z...WHEN LAKE EFFECT
SHOWERS WILL FADE AS WINDS SHIFT TO A MORE WESTERLY COMPONENT AND
MOISTURE WILL BE CUT OFF.
VFR TO HIGH-END MVFR STRATOCU AND SCT LIGHT SNOW SHOWERS/FLURRIES
WILL SPILL INTO CENTRAL MTNS TONIGHT. WINDS WILL SETTLE TO 6-8
KTS TONIGHT.
VFR WILL DOMINATE THE WEATHER PATTERN TOMORROW WITH ONLY POSSIBLE
MVFR AT BFD...MAINLY TOMORROW NIGHT.
OUTLOOK...
SAT...AM SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD AND JST.
SUN...SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD.
MON...LGT-MDT SNOW/LOW CIGS EXPECTED ACROSS THE NW HALF OF PA.
RAIN/MIXED PRECIP AND LOW CIGS POSS SE.
TUE AND WED...BLUSTERY AND VERY COLD WITH SNOW SHOWERS AND AREAS
OF REDUCED CIGS/VSBYS - MAINLY ACROSS THE NW HALF OF PENN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST SATURDAY FOR PAZ004.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT/CERU
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1126 AM CST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM CST SAT NOV 15 2014
FOCUS ON THE SNOW EVENT CURRENTLY UNDERWAY ACROSS OUR WESTERN
CWA... EXPECTED TO PROGRESS EAST THROUGH THE REGION OVER THE
NEXT 24 HOURS. OVERALL LOOKING AT A BROAD ISENTROPIC UPGLIDE
AHEAD OF OPEN WAVE...WHICH SHOULD RESULT IN FAIRLY UNIFORM SNOW
AMOUNTS ACROSS THE REGION. HOWEVER...CURRENT RADAR SHOWING A COUPLE
MORE DISTINCT BANDS NEAR MID LEVEL /750-650MB/ FRONTAL BOUNDARIES
PER RAP MODEL...SO COULD SEE SOME AREAS OF ENHANCEMENT THROUGHOUT
THE DAY. FRONTOGENESIS APPEARS TO BE FAIRLY TRANSIENT THOUGH...SO DO
NOT EXPECT HEAVIER BANDS TO SIT IN ANY ONE LOCATION FOR PROLONGED
PERIOD OF TIME. NORTHERN BAND APPEARS TO BE A LITTLE FARTHER NORTH
THAN PREVIOUSLY EXPECTED THOUGH...AIMING TOWARD THE HIGHWAY 14
CORRIDOR THROUGH THE MORNING. HAVE BUMPED UP SNOW AMOUNTS A BIT IN
THESE AREAS AS A RESULT...AND EXPANDED ADVISORY NORTHWARD TO COVER
ENTIRE CWA FOR WIDESPREAD 3 TO 5 INCHES.
IN ADDITION TO POTENTIALLY HIGHER BANDS...CONCERN FOR THIS EVENT IS
HIGH SNOW RATIOS GIVEN STRONG LIFT WITHIN DEEP DENDRITIC LAYER...
AND LIGHT WINDS ALLOWING DENDRITIC SNOW FLAKES TO HOLD TOGETHER.
GENERALLY STICKING WITH 16-18:1 RATIOS FOR BULK OF THE SNOWFALL...
BUT SOME MODELS INDICATE A BIT HIGHER...WHICH COULD PUSH AMOUNTS
CLOSER TO 6 INCH RANGE IN SOME AREAS. STILL EXPECT SNOW TO BE DONE
IN MOST AREAS BY MID-LATE EVENING...BUT WAVE IS A BIT SLOWER IN
DEPARTING THIS EVENING...SO EXTENDED ADVISORY TIMING IN OUR FAR
EAST THROUGH MIDNIGHT TONIGHT. GIVEN FLUFFY NATURE OF SNOWFALL...
COULD SEE A LITTLE BLOWING/DRIFTING OF FRESH SNOW AS NORTHWEST WINDS
PICK UP BEHIND THE FRONT ACROSS OUR SOUTHWEST AREAS THIS AFTERNOON
AND EVENING...AND WILL CONTINUE MENTION OF PATCHY BLOWING SNOW
THROUGH PARTS OF THE MISSOURI RIVER VALLEY. STRONGER WINDS OCCUR
AFTER BULK OF ACCUMULATION IS OVER THOUGH...SO AT THIS TIME HAVE NOT
EXTENDED HEADLINES TO COVER ANY BLOWING SNOW THREAT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 415 AM CST SAT NOV 15 2014
ON SUNDAY...INTENSIFYING LOW PRESSURE TRACKING THROUGH THE UPPER
MISSISSIPPI VALLEY/WESTERN GREAT LAKES REGION WILL PULL A COLD FRONT
THROUGH OUR AREA IN THE AFTERNOON. WHILE WINDS WILL INITIALLY BE OUT
OF THE WEST/SOUTHWEST EARLY IN THE DAY...THEY WILL TURN AROUND TO
THE NORTHWEST WITH THE PASSAGE OF THE SYSTEM...AND PICK UP IN A COLD
AIR ADVECTION REGIME. WITH THIS...GUSTS WILL RAMP UP TO 20 TO 30 KTS
ACROSS THE AREA. IN RESPONSE TO THIS...WILL BEGIN TO HAVE AREAS OF
BLOWING SNOW WITH FRESH SNOW COVER ON THE GROUND. WILL ALSO SEE THE
POSSIBILITY OF SCATTERED FLURRIES OVER PORTIONS OF THE AREA WITH
SOME CLOUD COVER AND VERY COLD THERMAL PROFILES SUPPORTIVE OF
DENDRITIC GROWTH. IN A THE WEST/SOUTHWESTERLY FLOW OUT AHEAD OF THE
FRONT...THE MISSOURI RIVER VALLEY WILL HAVE THE OPPORTUNITY TO WARM
INTO THE MID 20S BEFORE BEGINNING TO DROP OFF IN THE AFTERNOON AS
THE COLDER AIR FEEDS INTO THE AREA. BACK TO THE NORTH AND
EAST...HIGHS WILL ONLY MAKE IT INTO THE UPPER TEENS TO LOWER 20S.
STRONG GUSTY NORTHWESTERLY WINDS WILL PERSIST FOR SUNDAY NIGHT AND
MONDAY...KEEPING THE POSSIBILITY OF BLOWING SNOW ACROSS THE AREA
THROUGH THE PERIOD. THE WINDS WILL KEEP TEMPERATURES FROM DROPPING
OFF TOO DRAMATICALLY ON SUNDAY NIGHT...THOUGH STILL COLD WITH LOWS
IN THE SINGLE DIGITS. IN AN INCREASINGLY COLD AIRMASS WITH MONDAY
925 MB TEMPERATURES PROGGED TO BE JUST EITHER SIDE OF -15 C...IT
WILL BE A BITTERLY COLD DAY WITH HIGHS IN THE LOWER TO MID TEENS.
WITH THE AFOREMENTIONED WINDS...WIND CHILLS WILL BE FIERCE...RUNNING
IN THE SINGLE DIGITS BELOW ZERO TO TEENS BELOW ZERO.
WINDS WILL THEN RAMP DOWN ON MONDAY NIGHT AS A SURFACE RIDGE AXIS
SLIDES CLOSER TO THE AREA...BRINGING AN END TO ANY BLOWING SNOW.
STILL ENOUGH WIND HOWEVER TO KEEP OVERNIGHT LOWS SOMEWHAT IN
CHECK...BOTTOMING OUT JUST EITHER SIDE OF ZERO.
FOR THE REMINDER OF NEXT WEEK...THERE WILL BE A SLIGHT MODERATION OF
TEMPERATURES...ALBEIT STILL MUCH BELOW NORMAL...IN A NORTHWESTERLY
UPPER LEVEL FLOW. THIS WOULD BE MOST APPARENT TOWARD THE END OF THE
WEEK WHEN HIGHS ON FRIDAY COULD CLOSE IN ON THE LOWER 30S THROUGH
THE MISSOURI RIVER VALLEY. THERE DOES NOT APPEAR TO BE ANY
SIGNIFICANT PRECIPITATION PRODUCERS THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1124 AM CST SAT NOV 15 2014
MVFR TO OCCASIONAL IFR CONDITIONS IN SNOW TODAY...WITH CONDITIONS
GRADUALLY IMPROVING THE THE OVERNIGHT HOURS. WHILE MAINLY VFR
CONDITIONS ARE EXPECTED AFTER ABOUT 9Z TONIGHT IN MOST LOCATIONS
SOME PATCHY MVFR CEILINGS WILL BE POSSIBLE TOMORROW. BE PREPARED
FOR VERY STRONG WINDS AND REDUCED VISIBIITY IN BLOWING SNOW SUNDAY
NIGHT INTO MONDAY AFTERNOON.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR SDZ039-
040-054>056-060>062-065>071.
WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR SDZ038-
050-052-053-057>059-063-064.
MN...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR MNZ071-
072-080-089-097-098.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR MNZ081-
090.
IA...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR IAZ001-
012-020-031.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR IAZ002-
003-013-014-021-022-032.
NE...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR NEZ013-
014.
&&
$$
SHORT TERM...JH
LONG TERM...JM
AVIATION...08
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
535 AM CST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM CST SAT NOV 15 2014
FOCUS ON THE SNOW EVENT CURRENTLY UNDERWAY ACROSS OUR WESTERN
CWA... EXPECTED TO PROGRESS EAST THROUGH THE REGION OVER THE
NEXT 24 HOURS. OVERALL LOOKING AT A BROAD ISENTROPIC UPGLIDE
AHEAD OF OPEN WAVE...WHICH SHOULD RESULT IN FAIRLY UNIFORM SNOW
AMOUNTS ACROSS THE REGION. HOWEVER...CURRENT RADAR SHOWING A COUPLE
MORE DISTINCT BANDS NEAR MID LEVEL /750-650MB/ FRONTAL BOUNDARIES
PER RAP MODEL...SO COULD SEE SOME AREAS OF ENHANCEMENT THROUGHOUT
THE DAY. FRONTOGENESIS APPEARS TO BE FAIRLY TRANSIENT THOUGH...SO DO
NOT EXPECT HEAVIER BANDS TO SIT IN ANY ONE LOCATION FOR PROLONGED
PERIOD OF TIME. NORTHERN BAND APPEARS TO BE A LITTLE FARTHER NORTH
THAN PREVIOUSLY EXPECTED THOUGH...AIMING TOWARD THE HIGHWAY 14
CORRIDOR THROUGH THE MORNING. HAVE BUMPED UP SNOW AMOUNTS A BIT IN
THESE AREAS AS A RESULT...AND EXPANDED ADVISORY NORTHWARD TO COVER
ENTIRE CWA FOR WIDESPREAD 3 TO 5 INCHES.
IN ADDITION TO POTENTIALLY HIGHER BANDS...CONCERN FOR THIS EVENT IS
HIGH SNOW RATIOS GIVEN STRONG LIFT WITHIN DEEP DENDRITIC LAYER...
AND LIGHT WINDS ALLOWING DENDRITIC SNOW FLAKES TO HOLD TOGETHER.
GENERALLY STICKING WITH 16-18:1 RATIOS FOR BULK OF THE SNOWFALL...
BUT SOME MODELS INDICATE A BIT HIGHER...WHICH COULD PUSH AMOUNTS
CLOSER TO 6 INCH RANGE IN SOME AREAS. STILL EXPECT SNOW TO BE DONE
IN MOST AREAS BY MID-LATE EVENING...BUT WAVE IS A BIT SLOWER IN
DEPARTING THIS EVENING...SO EXTENDED ADVISORY TIMING IN OUR FAR
EAST THROUGH MIDNIGHT TONIGHT. GIVEN FLUFFY NATURE OF SNOWFALL...
COULD SEE A LITTLE BLOWING/DRIFTING OF FRESH SNOW AS NORTHWEST WINDS
PICK UP BEHIND THE FRONT ACROSS OUR SOUTHWEST AREAS THIS AFTERNOON
AND EVENING...AND WILL CONTINUE MENTION OF PATCHY BLOWING SNOW
THROUGH PARTS OF THE MISSOURI RIVER VALLEY. STRONGER WINDS OCCUR
AFTER BULK OF ACCUMULATION IS OVER THOUGH...SO AT THIS TIME HAVE NOT
EXTENDED HEADLINES TO COVER ANY BLOWING SNOW THREAT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 415 AM CST SAT NOV 15 2014
ON SUNDAY...INTENSIFYING LOW PRESSURE TRACKING THROUGH THE UPPER
MISSISSIPPI VALLEY/WESTERN GREAT LAKES REGION WILL PULL A COLD FRONT
THROUGH OUR AREA IN THE AFTERNOON. WHILE WINDS WILL INITIALLY BE OUT
OF THE WEST/SOUTHWEST EARLY IN THE DAY...THEY WILL TURN AROUND TO
THE NORTHWEST WITH THE PASSAGE OF THE SYSTEM...AND PICK UP IN A COLD
AIR ADVECTION REGIME. WITH THIS...GUSTS WILL RAMP UP TO 20 TO 30 KTS
ACROSS THE AREA. IN RESPONSE TO THIS...WILL BEGIN TO HAVE AREAS OF
BLOWING SNOW WITH FRESH SNOW COVER ON THE GROUND. WILL ALSO SEE THE
POSSIBILITY OF SCATTERED FLURRIES OVER PORTIONS OF THE AREA WITH
SOME CLOUD COVER AND VERY COLD THERMAL PROFILES SUPPORTIVE OF
DENDRITIC GROWTH. IN A THE WEST/SOUTHWESTERLY FLOW OUT AHEAD OF THE
FRONT...THE MISSOURI RIVER VALLEY WILL HAVE THE OPPORTUNITY TO WARM
INTO THE MID 20S BEFORE BEGINNING TO DROP OFF IN THE AFTERNOON AS
THE COLDER AIR FEEDS INTO THE AREA. BACK TO THE NORTH AND
EAST...HIGHS WILL ONLY MAKE IT INTO THE UPPER TEENS TO LOWER 20S.
STRONG GUSTY NORTHWESTERLY WINDS WILL PERSIST FOR SUNDAY NIGHT AND
MONDAY...KEEPING THE POSSIBILITY OF BLOWING SNOW ACROSS THE AREA
THROUGH THE PERIOD. THE WINDS WILL KEEP TEMPERATURES FROM DROPPING
OFF TOO DRAMATICALLY ON SUNDAY NIGHT...THOUGH STILL COLD WITH LOWS
IN THE SINGLE DIGITS. IN AN INCREASINGLY COLD AIRMASS WITH MONDAY
925 MB TEMPERATURES PROGGED TO BE JUST EITHER SIDE OF -15 C...IT
WILL BE A BITTERLY COLD DAY WITH HIGHS IN THE LOWER TO MID TEENS.
WITH THE AFOREMENTIONED WINDS...WIND CHILLS WILL BE FIERCE...RUNNING
IN THE SINGLE DIGITS BELOW ZERO TO TEENS BELOW ZERO.
WINDS WILL THEN RAMP DOWN ON MONDAY NIGHT AS A SURFACE RIDGE AXIS
SLIDES CLOSER TO THE AREA...BRINGING AN END TO ANY BLOWING SNOW.
STILL ENOUGH WIND HOWEVER TO KEEP OVERNIGHT LOWS SOMEWHAT IN
CHECK...BOTTOMING OUT JUST EITHER SIDE OF ZERO.
FOR THE REMINDER OF NEXT WEEK...THERE WILL BE A SLIGHT MODERATION OF
TEMPERATURES...ALBEIT STILL MUCH BELOW NORMAL...IN A NORTHWESTERLY
UPPER LEVEL FLOW. THIS WOULD BE MOST APPARENT TOWARD THE END OF THE
WEEK WHEN HIGHS ON FRIDAY COULD CLOSE IN ON THE LOWER 30S THROUGH
THE MISSOURI RIVER VALLEY. THERE DOES NOT APPEAR TO BE ANY
SIGNIFICANT PRECIPITATION PRODUCERS THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 535 AM CST SAT NOV 15 2014
WIDESPREAD MVFR-IFR CONDITIONS EXPECTED TODAY WITH SNOW MOVING
THROUGH THE REGION. CONDITIONS SHOULD GRADUALLY IMPROVE WEST TO
EAST AFTER 16/00Z AS SNOW COMES TO AN END BEHIND DEPARTING UPPER
WAVE AND ASSOCIATED FRONT. WINDS GENERALLY AT OR BELOW 10KT WITH
THE SNOW...BUT EXPECTED TO INCREASE WITH GUSTS 15-25KT AS WINDS
BECOME NORTHWESTERLY IN THE LATE AFTERNOON/EVENING. GUSTY WINDS
WILL LIKELY CREATE DRIFTING ACROSS RUNWAYS...AND COULD PRODUCE
LINGERING MVFR VISIBILITY IN BLOWING SNOW AT TIMES.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR SDZ039-
040-054>056-060>062-065>071.
WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR SDZ038-
050-052-053-057>059-063-064.
MN...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR MNZ071-
072-080-089-097-098.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR MNZ081-090.
IA...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR IAZ001-
012-020-031.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR IAZ002-003-013-014-021-022-032.
NE...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR NEZ013-
014.
&&
$$
SHORT TERM...JH
LONG TERM...JM
AVIATION...JH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
415 AM CST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM CST SAT NOV 15 2014
FOCUS ON THE SNOW EVENT CURRENTLY UNDERWAY ACROSS OUR WESTERN
CWA... EXPECTED TO PROGRESS EAST THROUGH THE REGION OVER THE
NEXT 24 HOURS. OVERALL LOOKING AT A BROAD ISENTROPIC UPGLIDE
AHEAD OF OPEN WAVE...WHICH SHOULD RESULT IN FAIRLY UNIFORM SNOW
AMOUNTS ACROSS THE REGION. HOWEVER...CURRENT RADAR SHOWING A COUPLE
MORE DISTINCT BANDS NEAR MID LEVEL /750-650MB/ FRONTAL BOUNDARIES
PER RAP MODEL...SO COULD SEE SOME AREAS OF ENHANCEMENT THROUGHOUT
THE DAY. FRONTOGENESIS APPEARS TO BE FAIRLY TRANSIENT THOUGH...SO DO
NOT EXPECT HEAVIER BANDS TO SIT IN ANY ONE LOCATION FOR PROLONGED
PERIOD OF TIME. NORTHERN BAND APPEARS TO BE A LITTLE FARTHER NORTH
THAN PREVIOUSLY EXPECTED THOUGH...AIMING TOWARD THE HIGHWAY 14
CORRIDOR THROUGH THE MORNING. HAVE BUMPED UP SNOW AMOUNTS A BIT IN
THESE AREAS AS A RESULT...AND EXPANDED ADVISORY NORTHWARD TO COVER
ENTIRE CWA FOR WIDESPREAD 3 TO 5 INCHES.
IN ADDITION TO POTENTIALLY HIGHER BANDS...CONCERN FOR THIS EVENT IS
HIGH SNOW RATIOS GIVEN STRONG LIFT WITHIN DEEP DENDRITIC LAYER...
AND LIGHT WINDS ALLOWING DENDRITIC SNOW FLAKES TO HOLD TOGETHER.
GENERALLY STICKING WITH 16-18:1 RATIOS FOR BULK OF THE SNOWFALL...
BUT SOME MODELS INDICATE A BIT HIGHER...WHICH COULD PUSH AMOUNTS
CLOSER TO 6 INCH RANGE IN SOME AREAS. STILL EXPECT SNOW TO BE DONE
IN MOST AREAS BY MID-LATE EVENING...BUT WAVE IS A BIT SLOWER IN
DEPARTING THIS EVENING...SO EXTENDED ADVISORY TIMING IN OUR FAR
EAST THROUGH MIDNIGHT TONIGHT. GIVEN FLUFFY NATURE OF SNOWFALL...
COULD SEE A LITTLE BLOWING/DRIFTING OF FRESH SNOW AS NORTHWEST WINDS
PICK UP BEHIND THE FRONT ACROSS OUR SOUTHWEST AREAS THIS AFTERNOON
AND EVENING...AND WILL CONTINUE MENTION OF PATCHY BLOWING SNOW
THROUGH PARTS OF THE MISSOURI RIVER VALLEY. STRONGER WINDS OCCUR
AFTER BULK OF ACCUMULATION IS OVER THOUGH...SO AT THIS TIME HAVE NOT
EXTENDED HEADLINES TO COVER ANY BLOWING SNOW THREAT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 415 AM CST SAT NOV 15 2014
ON SUNDAY...INTENSIFYING LOW PRESSURE TRACKING THROUGH THE UPPER
MISSISSIPPI VALLEY/WESTERN GREAT LAKES REGION WILL PULL A COLD FRONT
THROUGH OUR AREA IN THE AFTERNOON. WHILE WINDS WILL INITIALLY BE OUT
OF THE WEST/SOUTHWEST EARLY IN THE DAY...THEY WILL TURN AROUND TO
THE NORTHWEST WITH THE PASSAGE OF THE SYSTEM...AND PICK UP IN A COLD
AIR ADVECTION REGIME. WITH THIS...GUSTS WILL RAMP UP TO 20 TO 30 KTS
ACROSS THE AREA. IN RESPONSE TO THIS...WILL BEGIN TO HAVE AREAS OF
BLOWING SNOW WITH FRESH SNOW COVER ON THE GROUND. WILL ALSO SEE THE
POSSIBILITY OF SCATTERED FLURRIES OVER PORTIONS OF THE AREA WITH
SOME CLOUD COVER AND VERY COLD THERMAL PROFILES SUPPORTIVE OF
DENDRITIC GROWTH. IN A THE WEST/SOUTHWESTERLY FLOW OUT AHEAD OF THE
FRONT...THE MISSOURI RIVER VALLEY WILL HAVE THE OPPORTUNITY TO WARM
INTO THE MID 20S BEFORE BEGINNING TO DROP OFF IN THE AFTERNOON AS
THE COLDER AIR FEEDS INTO THE AREA. BACK TO THE NORTH AND
EAST...HIGHS WILL ONLY MAKE IT INTO THE UPPER TEENS TO LOWER 20S.
STRONG GUSTY NORTHWESTERLY WINDS WILL PERSIST FOR SUNDAY NIGHT AND
MONDAY...KEEPING THE POSSIBILITY OF BLOWING SNOW ACROSS THE AREA
THROUGH THE PERIOD. THE WINDS WILL KEEP TEMPERATURES FROM DROPPING
OFF TOO DRAMATICALLY ON SUNDAY NIGHT...THOUGH STILL COLD WITH LOWS
IN THE SINGLE DIGITS. IN AN INCREASINGLY COLD AIRMASS WITH MONDAY
925 MB TEMPERATURES PROGGED TO BE JUST EITHER SIDE OF -15 C...IT
WILL BE A BITTERLY COLD DAY WITH HIGHS IN THE LOWER TO MID TEENS.
WITH THE AFOREMENTIONED WINDS...WIND CHILLS WILL BE FIERCE...RUNNING
IN THE SINGLE DIGITS BELOW ZERO TO TEENS BELOW ZERO.
WINDS WILL THEN RAMP DOWN ON MONDAY NIGHT AS A SURFACE RIDGE AXIS
SLIDES CLOSER TO THE AREA...BRINGING AN END TO ANY BLOWING SNOW.
STILL ENOUGH WIND HOWEVER TO KEEP OVERNIGHT LOWS SOMEWHAT IN
CHECK...BOTTOMING OUT JUST EITHER SIDE OF ZERO.
FOR THE REMINDER OF NEXT WEEK...THERE WILL BE A SLIGHT MODERATION OF
TEMPERATURES...ALBEIT STILL MUCH BELOW NORMAL...IN A NORTHWESTERLY
UPPER LEVEL FLOW. THIS WOULD BE MOST APPARENT TOWARD THE END OF THE
WEEK WHEN HIGHS ON FRIDAY COULD CLOSE IN ON THE LOWER 30S THROUGH
THE MISSOURI RIVER VALLEY. THERE DOES NOT APPEAR TO BE ANY
SIGNIFICANT PRECIPITATION PRODUCERS THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1048 PM CST FRI NOV 14 2014
THROUGH 15Z CEILINGS AND VISIBILITIES WILL LOWER FROM THE WEST
FROM VFR TO AROUND 1K FEET AND BELOW 3SM IN SNOW. FROM 15/20Z TO
16/06Z CONDITIONS WILL IMPROVE SLOWLY FROM THE WEST TO CEILINGS
2-3K FEET AND VISIBILITY GREATER THAN 5SM AS SNOW ENDS. WEST OF A
BKX/FSD/SUX LINE...SKIES WILL CLEAR FROM THE WEST 16/00Z-06Z.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR SDZ039-
040-054>056-060>062-065>071.
WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR SDZ038-
050-052-053-057>059-063-064.
MN...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR MNZ071-
072-080-089-097-098.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR MNZ081-090.
IA...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR IAZ001-
012-020-031.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR IAZ002-003-013-014-021-022-032.
NE...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR NEZ013-
014.
&&
$$
SHORT TERM...JH
LONG TERM...JM
AVIATION...
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
751 PM CST SUN NOV 16 2014
.UPDATE...
THE COLD FRONT IS NOW LOCATED ACROSS OUR SOUTHERN COUNTIES. MUCH
COLDER WEATHER IS MOVING IN BEHIND THE BOUNDARY AND AT 8 PM THE
FREEZING LINE WAS JUST ENTERING OUR NORTHERN COUNTIES NEAR EDWARDS
AND KERR COUNTY. A LARGE AREA OF VERY LIGHT PRECIPITATION REMAINS
CONFINED TO AREAS NORTH OF OUR CWA AND THIS SHOULD CONTINUE TO BE
THE CASE FOR MOST OF THE NIGHT. THIS AFTERNOON THE HRRR HAD BEEN
SHOWING A BAND OF PRECIP PUSHING THROUGH SOUTH-CENTRAL TEXAS BUT
HAS SINCE BACKED OFF. THE BEST CHANCES FOR WINTER PRECIP TONIGHT
WILL BE IN THE NORTHERN HILL COUNTRY...NEAR LLANO AND BURNET
COUNTY THROUGH MIDNIGHT. CURRENTLY...A BAND OF SNOWFALL EXTENDS
SOUTH NEAR ELDORADO AND WITH A CONTINUED EASTWARD MOVEMENT THIS
WOULD QUICKLY CLIP LLANO AND BURNET COUNTIES. THE QUESTION THEN
TURNS INTO WHAT THE PRECIPITATION TYPE WOULD BE. ALL MODEL
FORECAST SOUNDINGS SHOW A WARM LAYER AROUND 750 MB THAT WOULD
LIKELY PREVENT SNOW THIS FAR SOUTH. HOWEVER...A FAIRLY DEEP SUB-
FREEZING LAYER BELOW 800 WOULD LEAD TO A SLEET/RAIN MIX OR ALL
SLEET. IF MODELS ARE OVERDOING THIS WARM LAYER...THEN BRIEF SNOW
WOULD BE POSSIBLE. AM NOT EXPECTING ACTIVITY TO BE HEAVY OR LAST
FOR A VERY LONG TIME SO THERE SHOULD NOT BE MANY IMPACTS. SINCE IT
WILL BE SUCH A SHORT-TERM TYPE EVENT WILL MOST LIKELY HANDLE ANY
IMPACTS WITH AN SPS LATER THIS EVENING IF NEEDED. MODEL SOUNDINGS
SHOW A LOT OF DRYING IN THE LOW-LEVELS AFTER 6Z AND MUCH OF THE
PRECIP SHOULD SHUT OFF. THE HRRR IS SHOWING THIS WELL.
HAMPSHIRE
&&
.PREV DISCUSSION... /ISSUED 507 PM CST SUN NOV 16 2014/
AVIATION...
A COLD FRONT IS PUSHING ACROSS THE AREA LATE THIS AFTERNOON. THE
COLD FRONT IS LOCATED SOUTH OF HIGHWAY 90 ACROSS OUR SOUTHERN COUNTIES
AND EXPECTED TO PUSH AWAY FROM OUR AREA EARLY THIS EVENING. IN THE WAKE OF
THE FROPA...BREEZY NORTHERLY WINDS WILL PREVAIL FOR MOST OF TONIGHT.
ALSO...GUSTY WINDS UP TO 30 KNOTS ARE POSSIBLE THROUGH ABOUT
MIDNIGHT TONIGHT. CIGS AND VSBYS WILL IMPROVE TO MVFR THIS EVENING AND
THEN BECOMING VFR OVERNIGHT/EARLY MONDAY. CLEARING IS FORECAST
ACROSS AREA SITES MONDAY MORNING WITH NORTHERLY WINDS OF 8 TO 12 KNOTS.
PREV DISCUSSION... /ISSUED 330 PM CST SUN NOV 16 2014/
SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...
UPPER AIR ANALYSIS THIS MORNING SHOWED A TROUGH SWINGING THROUGH
THE SOUTHWEST WITH SOUTHWESTERN FLOW ACROSS TEXAS. AT THE SURFACE
A COLD FRONT WAS ENTERING OUR CWA THIS AFTERNOON. IT STRETCHED
FROM WACO TO JUNCTION TO LANGTRY. THERE HAS ONLY BEEN ISOLATED
LIGHT RAIN WITH THE FRONT AND THE MAIN CHANGE IS THE STRONG NORTH
WINDS. THERE WAS MORE WIDESPREAD PRECIP ASSOCIATED WITH A SHORT
WAVE TROUGH MOVING INTO WEST TEXAS. THESE FEATURE WILL MOVE TOWARD
OUR FORECAST AREA LATER TONIGHT AND MODELS SUGGEST THAT WE WILL BE
ON THE SOUTHERN EDGE OF IT. WE WILL HAVE SLIGHT TO LOW END CHANCE
POPS THIS EVENING ACROSS OUR EASTERN COUNTIES. WITHIN THIS AREA
THERE WILL A CHANCE FOR SOME WINTER PRECIP IN PARTS OF BURNET AND
WILLIAMSON COUNTIES. IT LOOKS LIKE THE MOST LIKELY SCENARIO IS FOR
A MIX OF RAIN AND SLEET AND THE BEST TIME WILL BE BETWEEN ABOUT
9PM AND MIDNIGHT. PRECIP AMOUNTS SHOULD BE LIGHT AND WITH THE
GROUND SO WARM WE DO NOT EXPECT ANY WINTER PRECIP TO HAVE ANY
IMPACTS TONIGHT. AFTER MIDNIGHT PRECIP CHANCES WILL SHIFT TO THE
SOUTH WHERE TEMPERATURES WILL STAY ABOVE FREEZING SO WE ONLY HAVE
RAIN IN THE FORECAST. MORNING LOW TEMPERATURES WILL DROP TO OR
BELOW FREEZING ACROSS THE HILL COUNTRY AND EDWARDS PLATEAU. MONDAY
THE FRONT WILL MOVE AWAY AND THE UPPER TROUGH WILL SWING THROUGH
THE REGION. EXPECT SKIES TO CLEAR THROUGH THE DAY. CLEAR SKIES AND
LIGHT WINDS WILL ALLOW FOR GOOD RADIATIONAL COOLING MONDAY NIGHT
AND A WIDESPREAD FREEZE. EXPECT THAT A FREEZE WARNING WILL BE
NEEDED FOR THE PARTS OF THE CWA THAT HAVE NOT YET HAD A FREEZE.
LONG TERM (TUESDAY THROUGH SUNDAY)...
THE UPPER PATTERN WILL BECOME MORE ZONAL INTO THE MIDDLE OF THE
WEEK AS THE LOW LEVEL FLOW TURNS BACK TO THE SOUTHEAST. THIS WILL
LEAD TO A WARMING TREND INTO THURSDAY. BY THURSDAY AN OVER RUNNING
PATTERN WILL BECOME ESTABLISHED ACROSS THE EASTERN HALF OF THE
AREA. THERE WILL BE SLIGHT TO LOW END CHANCE POPS STARTING THURSDAY
AND CONTINUING THROUGH THE END OF THE PERIOD. THIS SEEMS LIKE TOO
LONG A PERIOD FOR RAIN EVEN THOUGH CHANCES WILL BE LOW. TIME FRAME
SHOULD COME INTO BETTER FOCUS AS WE GET CLOSER.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 33 50 29 53 36 / 20 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 33 51 24 53 32 / 20 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 33 53 28 54 35 / 20 0 0 0 10
BURNET MUNI AIRPORT 29 48 27 52 32 / 20 0 0 0 0
DEL RIO INTL AIRPORT 34 53 31 53 35 / 10 0 0 0 0
GEORGETOWN MUNI AIRPORT 31 49 25 52 33 / 20 0 0 0 0
HONDO MUNI AIRPORT 32 52 25 52 34 / 10 0 0 0 10
SAN MARCOS MUNI AIRPORT 33 52 26 53 33 / 20 0 0 0 10
LA GRANGE - FAYETTE REGIONAL 34 50 27 52 34 / 30 0 - - 10
SAN ANTONIO INTL AIRPORT 35 53 29 53 38 / 10 0 0 0 10
STINSON MUNI AIRPORT 36 53 29 54 37 / 10 0 0 0 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...17
SYNOPTIC/GRIDS...29
PUBLIC SERVICE/DATA COLLECTION...33
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
528 PM CST SUN NOV 16 2014
.UPDATE...
ISSUED AT 528 PM CST SUN NOV 16 2014
LOSS OF DAYTIME HEATING HAS HELPED TO REALLY CLEAR SKIES OUT BACK
IN THE DAKOTAS AND PARTS OF WESTERN MN. THIS CLEARING AREA LOOKS
POISED TO MOVE INTO THE REGION OVERNIGHT...SO MAY HAVE TO ADJUST
SKY COVER DOWNWARDS. STILL LOOKS LIKE CLOUDS WILL GREATLY INCREASE
IN THE MORNING AS THE SUN DESTABILIZES THE ATMOSPHERE UNDER THE
UNSEASONABLY COLD AIR ALOFT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 158 PM CST SUN NOV 16 2014
PRIMARY CHALLENGES INCLUDE LIGHT SNOW TONIGHT THROUGH MONDAY AND
STRONG NORTHWEST WINDS IN THE WAKE OF AN ARCTIC FRONT THROUGH THE
DAY ON MONDAY. 16.12Z GLOBAL MODELS ARE IN GOOD AGREEMENT THROUGH
19.12Z...DIVERGING SOMEWHAT THEREAFTER IN TIMING AND STRENGTH OF
SHORT-WAVES MOVING THROUGH PARENT NORTHWEST FLOW ALOFT...BECOMING
MORE ZONAL BY NEXT WEEKEND.
16.20Z SURFACE ANALYSIS SHOWS A STRONG ARCTIC/COLD FRONT DRAPED
FROM NEAR ROSEAU MN TO ABERDEEN SD. THIS FEATURE WILL SWEEP
ACROSS THE UPPER MISSISSIPPI RIVER VALLEY OVERNIGHT...BRINGING
WITH IT SCATTERED LIGHT SNOW SHOWERS AMOUNTING TO NO MORE THAN AN
INCH OF ACCUMULATION AND STRONG NORTHWEST WIND IN ITS WAKE.
SURFACE OBS BEHIND THE FRONT THIS AFTERNOON ACROSS ND SHOWING
GUSTS IN EXCESS OF 30 KTS AND ALTHOUGH THIS AIR MASS WILL MODIFY
SOMEWHAT AS IT DROPS SOUTH...16.19Z RAP BRINGS A NOSE OF 35 TO 40
KTS AT 0.5 KM INTO THE WESTERN FORECAST AREA BY MONDAY MORNING.
WITH A DEEPENING WELL-MIXED BOUNDARY LAYER...THIS SHOULD RESULT IN
WIDESPREAD 20 TO 25 MPH NORTHWEST WINDS WITH FREQUENT GUSTS UP TO
35 MPH. THESE WINDS COMBINED WITH 2 TO 4 INCHES OF NEW SNOWFALL
FROM SUNDAY AND SUNDAY NIGHT ACROSS PORTIONS OF SOUTHEAST MN AND
NORTHEAST IA WILL RESULT IN AREAS OF BLOWING AND DRIFTING SNOW...
REDUCING VISIBILITY AT TIMES TO ONE HALF MILE OR LESS. WILL ISSUE
A WINTER WEATHER ADVISORY FOR BLOWING SNOW FROM 17.12Z TO 18.00Z
ACROSS THE WESTERN THIRD OF THE FORECAST AREA. THE COMBINATION OF
POOR VISIBILITY AND BLOWING SNOW WILL CREATE DIFFICULT TRAVEL
CONDITIONS FOR THE MORNING COMMUTE AND CONTINUING THROUGH MUCH OF
THE DAY.
OTHERWISE...MONDAY WILL BE MOSTLY CLOUDY AND COLD WITH AFTERNOON
HIGHS ONLY IN THE TEENS. SCATTERED LIGHT SNOW SHOWERS WILL RESULT
IN MINOR ADDITIONAL ACCUMULATIONS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 158 PM CST SUN NOV 16 2014
850 HPA TEMPERATURES PLUNGE TO -18 C ACROSS THE FORECAST AREA BY
18.12Z (TUESDAY MORNING). THIS WILL RESULT IN THE COLDEST MORNING
SO FAR THIS SEASON. TEMPERATURES WILL FALL INTO THE SINGLE DIGITS
ABOVE ZERO WITH FAVORED COLD SPOTS DROPPING BELOW ZERO. COMBINED
WITH WESTERLY WINDS FROM 10 TO 15 MPH...WIND CHILL VALUES WILL BE
IN THE 10 TO 20 BELOW RANGE. THE REST OF TUESDAY WILL BE DRY AND
SHOULD SEE SOME PEAKS OF SUNSHINE LATE IN THE DAY AS MONDAY/S SNOW
MOVES OFF TO THE EAST. TEMPERATURES WILL TOP OUT IN THE MID TEENS.
A REINFORCING SHOT OF ARCTIC AIR WILL DROP SOUTH TUESDAY NIGHT
BEHIND THE NEXT COLD FRONT. MOST SNOW WILL FALL TO THE NORTH AND
EAST NEAREST THE BEST MID-LEVEL FORCING AND HIGHEST MOISTURE...
ALTHOUGH SOME SCATTERED LIGHT SNOW IS POSSIBLE ACROSS THE FORECAST
AREA WITH ACCUMULATIONS LESS THAN ONE INCH.
WEDNESDAY THROUGH FRIDAY WILL BE DRY AND UNSEASONABLY COLD. BROAD
SURFACE HIGH PRESSURE DRIFTS ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY THROUGH THIS PERIOD...CENTERED ACROSS NORTHERN MO BY 12Z
FRIDAY. THE REGION REMAINS FULLY ENTRENCHED WITHIN ARCTIC AIR
MASS THROUGH FRIDAY WITH DAILY HIGHS IN THE MID TEENS AND 20S AND
LOWS IN THE SINGLE DIGITS TO TEENS. DEPENDING ON CLOUD COVER...
THURSDAY NIGHT LOWS COULD RIVAL THOSE FROM TUESDAY MORNING.
MID-LEVEL THERMAL RIDGE FINALLY MAKES SOME EASTWARD PROGRESS BY
THE WEEKEND. WARM AIR ADVECTION REGIME SHOULD ALLOW TEMPERATURES
TO CLIMB BACK INTO THE 30S. HOWEVER...BOTH THE 16.12Z GFS AND
ECMWF SHOW THE NEXT STORM SYSTEM LIFTING NORTH FROM THE SOUTHERN
PLAINS OVER THE WEEKEND. THE ECMWF IS FARTHER WEST WITH ITS
PRECIP THAN THE GFS...SO FOR NOW WILL FOLLOW A BLENDED APPROACH
WITH 20 TO 30 POPS AND THE POTENTIAL FOR MIXED PRECIP GIVEN WARMER
TEMPERATURES ALOFT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 528 PM CST SUN NOV 16 2014
LOSS OF DAYTIME HEATING OVER THE LAST 2 HOURS HAS REALLY HELPED
GET RID OF A LOT OF MVFR CLOUDS ACROSS THE DAKOTAS AND MINNESOTA.
THIS TREND HAS RESULTED IN A MUCH MORE OPTIMISTIC TAF
FORECAST...ESPECIALLY FOR TONIGHT. AN ARCTIC COLD FRONT TRACKING
THROUGH MINNESOTA IS POISED TO CROSS THE TAF SITES TONIGHT. THERE
IS A BRIEF BAND OF LIGHT SNOW WITH VFR TO MVFR VISIBILITIES AHEAD
OF THE FRONT IN CENTRAL MN...WHICH COULD AFFECT BOTH TAF SITES.
RST BEING A HIGHER TERRAIN SITE AND MORE EXPOSED HAS THE BEST SHOT
OF SEEING THESE LOWER VISIBILITIES. CLOUDS THEN LOOK TO CLEAR OUT
AS WINDS SHIFT WEST TO NORTHWESTERLY AT 10-15 KT. ONCE THE SUN
COMES UP...ANTICIPATING MVFR STRATOCUMULUS TO FORM QUICKLY...
FOLLOWED BY SCATTERED-NUMEROUS SNOW SHOWERS A FEW HOURS
THEREAFTER. WITH WINDS BECOMING GUSTY AT 20-30 KT...STRONGEST AT
RST...BLSN WITH MVFR CONDITIONS ARE LIKELY AT RST. LATE IN THE
AFTERNOON...LOSS OF DAYTIME HEATING SHOULD ALLOW CEILINGS TO
CLIMB.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST MONDAY FOR MNZ086-
087-094-095.
IA...WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST MONDAY FOR IAZ008-
009-018-019.
&&
$$
UPDATE...AJ
SHORT TERM...ROGERS
LONG TERM...ROGERS
AVIATION...AJ
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
958 AM CST SAT NOV 15 2014
.UPDATE...
MID AND HIGH LEVEL CLOUDS WILL CONTINUE TO INCREASE FROM THE WEST
TODAY AS A SHORTWAVE APPROACHES. THE FORECAST SNOWFALL SEEMS TO BE
ON TRACK GIVEN UPSTREAM CONDITIONS AND THE 12Z NAM. LATEST NAM AND
RAP SOUNDINGS SUGGEST THE SNOW WILL START IN THE WEST BY 4 PM AND
IN THE EAST BY 6 PM. STILL LOOKS LIKE THE BULK OF SNOW WILL FALL
PRIOR TO MIDNIGHT...WITH SOME LINGERING LIGHT ACCUMULATIONS
THROUGH THE REMAINDER OF THE NIGHT. STORM TOTALS OF 1 TO 2 INCHES
STILL LOOKS ABOUT RIGHT.
&&
.AVIATION/18Z TAFS/...
MID AND HIGH LEVEL CLOUDS WILL CONTINUE TO INCREASE FROM THE WEST
TODAY AS A SHORTWAVE APPROACHES. LATEST NAM AND RAP SOUNDINGS
SUGGEST THE SNOW WILL START IN THE WEST BY 4 PM AND IN THE EAST BY
6 PM. STILL LOOKS LIKE THE BULK OF SNOW WILL FALL PRIOR TO
MIDNIGHT...WITH SOME LINGERING LIGHT ACCUMULATIONS THROUGH THE
REMAINDER OF THE NIGHT. STORM TOTALS OF 1 TO 2 INCHES STILL LOOKS
ABOUT RIGHT. IT WILL BE A DRY SNOW...WITH LIQUID TO SNOW RATIOS OF
AROUND 17 TO 1.
UPSTREAM OBS AND SOUNDINGS SUGGEST IFR/MVFR CIGS WITH THE
SNOWFALL...WITH VSBYS DROPPING TO 1 TO 2 MILES...POSSIBLY BRIEFLY
DOWN TO 1/2SM.
LOOKS LIKE MVFR CIGS MAY LINGER FOR MUCH OF SUNDAY...AS A SECOND
SHORTWAVE MOVES THROUGH WHILE A THIRD WAVE APPROACHES. WILL
PROBABLY SEE A LITTLE LIGHT SNOW AT TIMES SUNDAY...BUT NOT
EXPECTING ADDITIONAL ACCUMULATIONS.
&&
.PREV DISCUSSION... /ISSUED 330 AM CST SAT NOV 15 2014/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
MID LEVEL CLOUDS OVER NRN IL AND WEST OF THE MS RIVER ASSOCIATED
WITH LEADING EDGE OF MID LEVEL WARM ADVECTION. WARM ADVECTION
PATTERN IS AHEAD OF A SHORTWAVE TROUGH OVER CO AND A STRONGER WAVE
OVER MT/IDAHO. THE CO SHORTWAVE WILL LIFT NEWD AND MOVE ACROSS SRN
WI THIS EVENING. WEAK MID LEVEL WARM ADVECTION AND FRONTOGENESIS
IS EXPECTED DURING THIS TIME BUT THE PVA IS MORE PRONOUNCED. THE
LARGER UPPER TROUGH WILL THEN MOVE INTO WEST CENTRAL WI BY 12Z SUN
BUT THE 500 MB DRY SLOT WILL KEEP THE SNOW VERY LIGHT.
THUS MOST OF THE SNOW ACCUMULATIONS WILL OCCUR FROM LATE THIS
AFTERNOON INTO THE EVENING HOURS. QPF TOTALS ARE RANGING FROM
0.08-0.12 INCHES WITH HIGH SNOW RATIOS DUE TO THE VERY COLD
TROPOSPHERE. SNOW TOTALS OF 1-2 INCHES ARE EXPECTED WITH THE
HIGHER VALUES OVER THE WRN CWA.
HIGH TEMPS TO REMAIN IN THE MID TO UPPER 20S TODAY WITH THE
INCREASING CLOUDS. THE CLOUDS...SNOW...AND WEAK WARM ADVECTION TNT
WILL KEEP TEMPS IN THE LOWER 20S FOR MOST OF THE NIGHT.
SHORT TERM...SUNDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE IS
MEDIUM.
MODELS IN GOOD AGREEMENT WITH 500 MB VORTICITY MAXIMUM SLIDING
EAST ACROSS THE AREA DURING THE MORNING...THEN SLOWLY TO THE EAST
OF THE AREA IN THE AFTERNOON. AREA FORECAST SOUNDINGS SHOW ENOUGH
DEEP MOISTURE WITHIN DEEP DENDRITE SNOW GROWTH ZONE TO MAINTAIN
LOWER END POPS IN THE NORTH AND EAST DURING THE MORNING.
MAY SEE SOME FLURRIES IN THE AFTERNOON WITH STEEP LOW LEVEL LAPSE
RATES AND SOME LINGERING MOISTURE. SKIES SHOULD BECOME PARTLY
SUNNY IN THE AFTERNOON. COLD HIGHS IN THE UPPER 20S TO LOWER 30S
ARE EXPECTED.
ARCTIC COLD FRONT MOVES EAST THROUGH THE AREA BY EARLY SUNDAY
EVENING...WITH STRONG COLD AIR ADVECTION SUNDAY NIGHT INTO MONDAY
ACROSS THE AREA. THIS WILL BRING AN EVEN COLDER AIRMASS INTO THE
REGION.
925 MB TEMPERATURES SUGGEST HIGHS ONLY IN THE UPPER TEENS TO
LOWER 20S MONDAY...WITH LOWS SUNDAY NIGHT INTO THE TEENS AND
MONDAY NIGHT IN THE 8 TO 13 ABOVE ZERO RANGE. TIGHT PRESSURE
GRADIENT WITH DEEPENING LOW TO THE NORTH WILL BRING GUSTY WEST
WINDS...WHICH WILL BRING WIND CHILLS DOWN INTO THE SINGLE DIGITS
SUNDAY NIGHT...AND THE SINGLE DIGITS BELOW ZERO MONDAY NIGHT.
MODELS GENERALLY SHOWING A 500 MB LOW DEVELOPING OVER NORTHERN
MINNESOTA BY SUNDAY NIGHT...THEN MOVING EAST OVER LAKE SUPERIOR
ON MONDAY. A 500 MB VORTICITY MAXIMUM SHIFTS EAST THROUGH THE AREA
SUNDAY NIGHT...WITH MORE VORTICITY MAXIMA MOVING THROUGH ON
MONDAY. AREA FORECAST SOUNDINGS SHOW ENOUGH LOW LEVEL MOISTURE AND
STEEP LAPSE RATES WITHIN DENDRITE SNOW GROWTH ZONE TO MAINTAIN
POPS FOR SNOW SHOWERS SUNDAY NIGHT INTO MONDAY.
LONG TERM...TUESDAY THROUGH FRIDAY...FORECAST CONFIDENCE IS
MEDIUM.
GFS/ECMWF GENERALLY KEEP THE REGION WITHIN NORTHWEST FLOW AT 500
MB THROUGH THE REST OF THE WEEK. THIS SHOULD KEEP THE REGION COLD
DURING THIS TIME.
500 MB SHORTWAVE TROUGH SLIDES SOUTHEAST THROUGH THE AREA TUESDAY
NIGHT...WITH A TRAILING VORTICITY MAXIMUM CLIPPING OR SHIFTING
THROUGH THE REGION WEDNESDAY. MOISTURE IS MODEST DURING THIS
TIME...SO KEPT JUST LOW END POPS IN THE NORTH AND NORTHEAST DURING
THIS TIME.
MODELS THEN DIFFER MORE LATER IN THE WEEK WITH TRENDS...SO USED
CONSENSUS POPS AND TEMPERATURES FOR NOW.
AVIATION/12Z TAFS/...
VFR CONDITIONS UNTIL THE LIGHT SNOW STARTS FROM WEST TO EAST
ACROSS SRN WI DURING THE LATE AFTERNOON. CIGS TO FALL TO 1-2 KFT
WITH VSBYS OF 1-2 MILES WITH THE SNOW INTO THE EVENING HOURS. THE
HEAVIEST SNOW WILL END BY LATE EVENING BUT VERY LIGHT SNOW WILL
CONTINUE AT TIMES FROM THE LATE EVENING THROUGH THE OVERNIGHT.
VSBYS DURING THIS TIME WILL RANGE FROM 3-5SM BUT MAY RISE TO P6SM
BEFORE 12Z SUN. LOW STRATUS TO CONTINUE INTO SUN AM.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...DDV
TODAY/TONIGHT AND AVIATION...GEHRING
SUNDAY THROUGH FRIDAY...WOOD
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
433 AM MST SAT NOV 15 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 253 AM MST SAT NOV 15 2014
MAIN CONCERN IN THE NEAR TERM IS ACCUMULATING SNOW ACROSS SOUTHEAST
WY AND THE WESTERN NE PANHANDLE. WINTER WEATHER ADVISORIES LOOK GOOD
AND HAVE MADE NO CHANGES WITH THE MORNING FCST PACKAGE. HAVE SEEN A
RELATIVE LULL IN SNOW SHOWERS OVERNIGHT WITH SUBSIDENCE AND SOMEWHAT
DRY AIR ALOFT. HOWEVER...POTENT MIDLVL SHORTWAVE EVIDENT ON MORNING
WATER VAPOR LOOP OVER THE PAC NW WILL MOVE SOUTHEAST TODAY. COOLING
CLOUD TOPS OVER CENTRAL WY SUGGEST AN UPTICK IN PCPN COVERAGE OVER
THE NEXT FEW HOURS...SO WILL KEEP CATEGORICAL POPS GOING. LOOKING AT
TWO DISTINCT AREAS OF SNOW ACCUMULATIONS. FIRST ACROSS THE NORTHERN
TIER OF COUNTIES WITH FRONTOGENESIS ALONG THE SFC FRONT. SECOND
ALONG AND WEST OF THE LARAMIE RANGE WITHIN THE LEFT EXIT REGION OF A
105 KT H25 JET STREAK NOW ENTERING NORTHERN UT. BOTH AREAS COINCIDE
WELL WITH A MIDLVL MOISTURE PLUME OVERSPREADING THE CWA. A GENERAL 2
TO 5 INCH SNOWFALL SEEMS PROBABLE IN THESE CORRIDORS. EVEN IF WE DO
NOT SEE ADVISORY CRITERIA AMOUNTS...NORTHWEST WINDS WILL GUST IN
EXCESS OF 30 MPH TODAY WHICH WILL CREATE BLOWING/DRIFTING. WEBCAMS
ALREADY LOOK QUITE NASTY IN THE RAWLINS IN ELK MOUNTAIN AREAS AS OF
09Z THIS MORNING. THOUGHT ABOUT A TEMPORAL EXTENTION OF THE ADVISORY
THROUGH THE AFTN FOR BLOWING SNOW AFTER ACCUMULATIONS END...BUT WILL
LET THE DAY SHIFT MONITOR CONDITIONS TO SEE JUST HOW BAD VISIBILITY
BECOMES LATER ON.
SNOW HAS BEEN DIFFICULT TO COME BY IN THE CHEYENNE AREA SO FAR. IT
STILL LOOKS LIKE WE HAVE A WINDOW OF OPPORTUNITY IN THE 12-15Z TIME
FRAME AS THE NAM SHOWS A BAND OF MODERATE H7 FRONTOGENESIS FROM THE
SOUTHERN LARAMIE RANGE EAST INTO KIMBALL COUNTY NE. MAY BE ENOUGH
FOR A QUICK 1 TO 2 INCHES...BUT NOT MUCH MORE. WITH NORTHWEST WINDS
GUSTING 25 TO 35 MPH...DAY SHIFT MIGHT NEED TO CONSIDER A BLOWING
SNOW ADVISORY FOR CENTRAL AND EASTERN LARAMIE COUNTY. THE MOUNTAINS
STILL LOOK PRIME FOR 8 TO 12 INCHES OF TOTAL ACCUMULATION. NVA WILL
SPREAD ACROSS THE AREA BY LATE AFTN...SO EXPECT A GRADUAL DECREASE
IN PCPN COVERAGE FROM NORTHWEST TO SOUTHEAST THROUGH EARLY EVE. DRY
AFTER 00Z OUTSIDE OF A FEW FLURRIES. STRONG LLVL COLD AIR ADVECTION
WILL CONTINUE TODAY WITH THE FROPA...WITH GFS H7 TEMPS PLUNGING TO
THE -17C TO -20C RANGE BY 00Z SUN. SURFACE TEMPS WILL MOST LIKELY
HOLD STEADY TODAY OR EVEN FALL SLIGHTLY INTO THE AFTN. DRYING ALOFT
SIGNALS CLEARING INTO TONIGHT...AND WITH FRESH SNOWPACK COMES VERY
COLD TEMPERATURES TONIGHT. GUSTY WEST WINDS MIGHT KEEP THINGS MIXED
ENOUGH TO PREVENT TEMPERATURES FROM REALLY TANKING...BUT IT WILL BE
SUFFICIENT FOR DANGEROUS WIND CHILLS BETWEEN -20 AND -30F. EXPECT
WIND CHILL ADVISORIES WILL BE NECESSARY.
BOTH THE NAM AND GFS SUGGEST A FAIRLY POTENT SHORTWAVE DIVING SOUTH
ACROSS THE WESTERN DAKOTAS ON SUN AFTN. WHILE THIS DOES PROVIDE A
REINFORCING SHOT OF COLD AIR...THE GOOD CAA DOES NOT ARRIVE UNTIL
LATE. AS SUCH...EXPECT A PERIOD OF GUSTY WEST/DOWNSLOPE WINDS EAST
OF THE LARAMIE RANGE TO CONTRIBUTE TO COMPRESSIONAL WARMING THROUGH
EARLY AFTN. TRENDED HIGHER FOR MAX TEMPS BECAUSE OF THIS. MOISTENING
ALOFT AND STRONG PVA SUGGESTS LIGHT SNOW SHOWERS ACROSS OUR NORTHERN
AND EASTERN ZONES...SO ADDED LOW-END POPS THERE. COOLER FOR MON WITH
CYCLONIC FLOW ALOFT AND SURFACE HIGH PRESSURE ENCOMPASSING MUCH OF
THE CENTRAL AND NORTHERN ROCKIES.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 253 AM MST SAT NOV 15 2014
LONG TERM LOOKS DRY FOR THE MOST PART WITH TEMPERATURES BACK TO
NEAR NORMAL FOR THIS TIME OF YEAR. WE STAY IN A NORTHWEST FLOW
THAT COULD BRING SOME QUICK HITTING SNOW SHOWERS MOSTLY TO THE
MOUNTAINS. THE MOST PROMINENT BEING THURSDAY. ECMWF ADVERTISING
THIS WITH THE GFS SOLUTION ON THE SHORTWAVE FURTHER NORTH AND EAST
OF OUR CWFA. DID KEEP SOME LOW CHANCE POPS IN THE FORECAST FOR THE
MOUNTAINS. MOST OTHER PLACES DRY THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 430 AM MST SAT NOV 15 2014
BASED 12Z TERMINAL FORECASTS OFF THE LATEST HRRR FORECAST.
CURRENT MOSAIC RADAR SHOWING SNOW SHOWERS INCREASING IN COVERAGE.
SEEING BAND OF MORE INTENSE SNOW JUST NORTH OF KCYS THIS MORNING
THAT IS MOVING SOUTH...SO KCYS SHOULD BE COMING DOWN HARD OVER THE
NEXT HOUR OR SO. MORNING HOURS THROUGH 18Z WILL SEE THE MOST
WIDESPREAD IFR/LIFR CONDITIONS ACROSS SOUTHEAST WYOMING AND
NEBRASKA PANHANDLE WITH IMPROVING CONDITIONS AFTERWARDS.
&&
.FIRE WEATHER...
ISSUED AT 253 AM MST SAT NOV 15 2014
NO FIRE WEATHER CONCERNS THROUGH THIS WEEKEND. ANOTHER ARCTIC SYSTEM
WILL BRING SNOW ACROSS MOST AREAS THROUGH SATURDAY. SEVERAL INCHES
OF SNOW WILL ACCUMULATE...ESPECIALLY IN THE HIGHER ELEVATIONS OF
SOUTHERN WYOMING. THIS SNOW WILL BE FOLLOWED BY BRISK SURFACE WIND
AND COLD TEMPERATURES SUNDAY INTO SUNDAY NIGHT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 11 AM MST THIS MORNING FOR
WYZ101>103-112-114.
WINTER WEATHER ADVISORY UNTIL 1 PM MST THIS AFTERNOON FOR
WYZ104>106-109>111-113-115>117.
NE...WINTER WEATHER ADVISORY UNTIL 11 AM MST THIS MORNING FOR NEZ002-
095.
&&
$$
SHORT TERM...CLH
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
253 AM MST SAT NOV 15 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 253 AM MST SAT NOV 15 2014
MAIN CONCERN IN THE NEAR TERM IS ACCUMULATING SNOW ACROSS SOUTHEAST
WY AND THE WESTERN NE PANHANDLE. WINTER WEATHER ADVISORIES LOOK GOOD
AND HAVE MADE NO CHANGES WITH THE MORNING FCST PACKAGE. HAVE SEEN A
RELATIVE LULL IN SNOW SHOWERS OVERNIGHT WITH SUBSIDENCE AND SOMEWHAT
DRY AIR ALOFT. HOWEVER...POTENT MIDLVL SHORTWAVE EVIDENT ON MORNING
WATER VAPOR LOOP OVER THE PAC NW WILL MOVE SOUTHEAST TODAY. COOLING
CLOUD TOPS OVER CENTRAL WY SUGGEST AN UPTICK IN PCPN COVERAGE OVER
THE NEXT FEW HOURS...SO WILL KEEP CATEGORICAL POPS GOING. LOOKING AT
TWO DISTINCT AREAS OF SNOW ACCUMULATIONS. FIRST ACROSS THE NORTHERN
TIER OF COUNTIES WITH FRONTOGENESIS ALONG THE SFC FRONT. SECOND
ALONG AND WEST OF THE LARAMIE RANGE WITHIN THE LEFT EXIT REGION OF A
105 KT H25 JET STREAK NOW ENTERING NORTHERN UT. BOTH AREAS COINCIDE
WELL WITH A MIDLVL MOISTURE PLUME OVERSPREADING THE CWA. A GENERAL 2
TO 5 INCH SNOWFALL SEEMS PROBABLE IN THESE CORRIDORS. EVEN IF WE DO
NOT SEE ADVISORY CRITERIA AMOUNTS...NORTHWEST WINDS WILL GUST IN
EXCESS OF 30 MPH TODAY WHICH WILL CREATE BLOWING/DRIFTING. WEBCAMS
ALREADY LOOK QUITE NASTY IN THE RAWLINS IN ELK MOUNTAIN AREAS AS OF
09Z THIS MORNING. THOUGHT ABOUT A TEMPORAL EXTENTION OF THE ADVISORY
THROUGH THE AFTN FOR BLOWING SNOW AFTER ACCUMULATIONS END...BUT WILL
LET THE DAY SHIFT MONITOR CONDITIONS TO SEE JUST HOW BAD VISIBILITY
BECOMES LATER ON.
SNOW HAS BEEN DIFFICULT TO COME BY IN THE CHEYENNE AREA SO FAR. IT
STILL LOOKS LIKE WE HAVE A WINDOW OF OPPORTUNITY IN THE 12-15Z TIME
FRAME AS THE NAM SHOWS A BAND OF MODERATE H7 FRONTOGENESIS FROM THE
SOUTHERN LARAMIE RANGE EAST INTO KIMBALL COUNTY NE. MAY BE ENOUGH
FOR A QUICK 1 TO 2 INCHES...BUT NOT MUCH MORE. WITH NORTHWEST WINDS
GUSTING 25 TO 35 MPH...DAY SHIFT MIGHT NEED TO CONSIDER A BLOWING
SNOW ADVISORY FOR CENTRAL AND EASTERN LARAMIE COUNTY. THE MOUNTAINS
STILL LOOK PRIME FOR 8 TO 12 INCHES OF TOTAL ACCUMULATION. NVA WILL
SPREAD ACROSS THE AREA BY LATE AFTN...SO EXPECT A GRADUAL DECREASE
IN PCPN COVERAGE FROM NORTHWEST TO SOUTHEAST THROUGH EARLY EVE. DRY
AFTER 00Z OUTSIDE OF A FEW FLURRIES. STRONG LLVL COLD AIR ADVECTION
WILL CONTINUE TODAY WITH THE FROPA...WITH GFS H7 TEMPS PLUNGING TO
THE -17C TO -20C RANGE BY 00Z SUN. SURFACE TEMPS WILL MOST LIKELY
HOLD STEADY TODAY OR EVEN FALL SLIGHTLY INTO THE AFTN. DRYING ALOFT
SIGNALS CLEARING INTO TONIGHT...AND WITH FRESH SNOWPACK COMES VERY
COLD TEMPERATURES TONIGHT. GUSTY WEST WINDS MIGHT KEEP THINGS MIXED
ENOUGH TO PREVENT TEMPERATURES FROM REALLY TANKING...BUT IT WILL BE
SUFFICIENT FOR DANGEROUS WIND CHILLS BETWEEN -20 AND -30F. EXPECT
WIND CHILL ADVISORIES WILL BE NECESSARY.
BOTH THE NAM AND GFS SUGGEST A FAIRLY POTENT SHORTWAVE DIVING SOUTH
ACROSS THE WESTERN DAKOTAS ON SUN AFTN. WHILE THIS DOES PROVIDE A
REINFORCING SHOT OF COLD AIR...THE GOOD CAA DOES NOT ARRIVE UNTIL
LATE. AS SUCH...EXPECT A PERIOD OF GUSTY WEST/DOWNSLOPE WINDS EAST
OF THE LARAMIE RANGE TO CONTRIBUTE TO COMPRESSIONAL WARMING THROUGH
EARLY AFTN. TRENDED HIGHER FOR MAX TEMPS BECAUSE OF THIS. MOISTENING
ALOFT AND STRONG PVA SUGGESTS LIGHT SNOW SHOWERS ACROSS OUR NORTHERN
AND EASTERN ZONES...SO ADDED LOW-END POPS THERE. COOLER FOR MON WITH
CYCLONIC FLOW ALOFT AND SURFACE HIGH PRESSURE ENCOMPASSING MUCH OF
THE CENTRAL AND NORTHERN ROCKIES.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 253 AM MST SAT NOV 15 2014
LONG TERM LOOKS DRY FOR THE MOST PART WITH TEMPERATURES BACK TO
NEAR NORMAL FOR THIS TIME OF YEAR. WE STAY IN A NORTHWEST FLOW
THAT COULD BRING SOME QUICK HITTING SNOW SHOWERS MOSTLY TO THE
MOUNTAINS. THE MOST PROMINENT BEING THURSDAY. ECMWF ADVERTISING
THIS WITH THE GFS SOLUTION ON THE SHORTWAVE FURTHER NORTH AND EAST
OF OUR CWFA. DID KEEP SOME LOW CHANCE POPS IN THE FORECAST FOR THE
MOUNTAINS. MOST OTHER PLACES DRY THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1023 PM MST FRI NOV 14 2014
BASED 06Z TERMINAL FORECASTS OFF THE LATEST HRRR FORECAST. STARTED
LOWERING FLIGHT CONDITIONS A LITTLE EARLIER. CURRENT MOSAIC RADAR
SHOWING SNOW SHOWERS MOVING INTO CARBON COUNTY...SO KRWL SHOULD BE
COMING DOWN SOON. MORNING HOURS THROUGH 18Z WILL SEE THE MOST
WIDESPREAD IFR/LIFR CONDITIONS ACROSS SOUTHEAST WYOMING AND
NEBRASKA PANHANDLE WITH IMPROVING CONDITIONS AFTERWARDS.
&&
.FIRE WEATHER...
ISSUED AT 253 AM MST SAT NOV 15 2014
NO FIRE WEATHER CONCERNS THROUGH THIS WEEKEND. ANOTHER ARCTIC SYSTEM
WILL BRING SNOW ACROSS MOST AREAS THROUGH SATURDAY. SEVERAL INCHES
OF SNOW WILL ACCUMULATE...ESPECIALLY IN THE HIGHER ELEVATIONS OF
SOUTHERN WYOMING. THIS SNOW WILL BE FOLLOWED BY BRISK SURFACE WIND
AND COLD TEMPERATURES SUNDAY INTO SUNDAY NIGHT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 11 AM MST THIS MORNING FOR
WYZ101>103-112-114.
WINTER WEATHER ADVISORY UNTIL 1 PM MST THIS AFTERNOON FOR
WYZ104>106-109>111-113-115>117.
NE...WINTER WEATHER ADVISORY UNTIL 11 AM MST THIS MORNING FOR NEZ002-
095.
&&
$$
SHORT TERM...CLH
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1027 PM MST FRI NOV 14 2014
.UPDATE...
ISSUED AT 934 PM MST FRI NOV 14 2014
04Z SFC ANALYSIS SHOWS COLD FRONT LOCATED FROM AROUND GUERNSEY
EAST TO BETWEEN ALLIANCE AND HEMINGFORD. NORTH OF THE FRONT
TEMPERATURES HAVE TUMBLED INTO THE TEENS...WITH 20S AND EVEN SOME
30S REMAINING SOUTH OF THE FRONT ALONG THE I-80 CORRIDOR. ALTHOUGH
AREA RADAR BEAMS ARE OVERSHOOTING MUCH OF THE SNOW...WEBCAMS
CONFIRM THAT SNOW WAS FALLING IN AREAS FROM GLENROCK EAST TO
DOUGLAS...HARRISON AND CHADRON. ALTHOUGH ACCUMULATIONS APPEAR TO
BE RELATIVELY LIGHT THUS FAR...PERHAPS UP TO AN INCH IN A FEW
AREAS. BOTH 00Z NAM/GFS HAVE A GOOD HANDLE ON THIS 1-2 INCH SNOW
BAND IN THIS AREA THRU MIDNIGHT. FRONT WILL SHIFT SOUTH OF THE
CWFA THRU THE MORNING HOURS SATURDAY...CARRYING BEST FRONTAL
FORCING WITH IT. AS SUCH...BAND OF HEAVIER SNOW WILL SPREAD SOUTH
INTO THE REMAINDER OF THE AREA BY SUNRISE OR SHORTLY THEREAFTER.
SNOW WILL BE OUT OF THE AREA BY EARLY AFTERNOON. DIDNT NEED TO
MAKE ANY CHANGES TO CURRENT HIGHLIGHT PACKAGES...ALTHOUGH DID
ADJUST SNOWFALL ACCUMS SLIGHTLY...DOWNWARD IN THE NORTH PLATTE
RIVER VALLEY AND PERHAPS SLIGHTLY LESS ELSEWHERE AS WELL. ADDED
BLOWING SNOW TO THE FORECAST AS WELL AS POST-FRONTAL NORTHERLIES
WILL GUST TO 25-30 MPH AT TIMES...ESPECIALLY TOMORROW AFTERNOON.
THE COMBINATION OF WINDS...SNOW AND SUB-ZERO WIND CHILLS WILL NOT
MAKE FOR A DAY TO SPEND MUCH TIME OUTDOORS ON SATURDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 357 PM MST FRI NOV 14 2014
COLD FRONT POISED JUST TO THE NORTH OF THE FORECAST AREA THIS
AFTERNOON. UPPER LEVEL WESTERLY FLOW PARALLELING THE FRONT AND
KEEPING IT FROM MAKING MUCH PROGRESS TO THE SOUTH. SNOW SHOULD BEGIN
SPREADING EAST ACROSS CONVERSE/NIOBRARA COUNTIES BETWEEN 00Z-03Z/SAT
AND INTO DAWES AND NORTHERN SIOUX COUNTIES IN THE NEBRASKA PANHANDLE
BETWEEN 03Z-05Z/SAT. BOTH THE NAM12 AND HRRR KEEP THE SNOW CONFINED
TO THESE AREAS THROUGH 06Z/SAT. ABOUT THAT TIME...MORE ROBUST BAND
OF SNOW WILL BEGIN TO DEVELOP OVER CARBON COUNTY...ESPECIALLY ALONG
THE INTERSTATE 80 CORRIDOR AND THE MEDICINE BOW AND SIERRA MADRE
RANGES. STRONGER FRONTAL SURGE COMES AFTER ABOUT 08Z/SAT AND PUSHES
TO THE SOUTHERN BORDER OF THE FORECAST AREA BY 13Z/SAT.
BEST SNOWFALL ALONG AND EAST OF I-25 SHOULD COME WITH AND SHORTLY
BEHIND THE FRONTAL PASSAGE. PLATTE...GOSHEN...AND LARAMIE COUNTIES
ALONG WITH THE REMAINDER OF THE PANHANDLE SHOULD SEE 1 TO 3 INCH
AMOUNTS. FRONTOGENETIC FORCING DOES FAVOR SOME ENHANCED LIFT IN
LARAMIE COUNTY WHERE IMPACTS COULD STILL NECESSITATE AN UPGRADE TO A
WINTER WEATHER ADVISORY. THE EVENING SHIFT WILL NEED TO MONITOR
TRENDS FROM 00Z OUTPUT CLOSELY. IN ADDITION TO THE
SNOW...NORTHERLY WIND OF 15 TO 30 MPH WILL PREVAIL FOLLOWING COLD
FRONTAL PASSAGE. ELSEWHERE...ADVISORIES LOOK TO BE IN GOOD SHAPE
WITH FORECAST STILL ON THE CORRECT TRACK. AIRMASS SLOWLY DRIES
AFTER 18Z/SAT BUT ANY SUN WILL JUST ALLOW FOR COLD AIR
STRATOCUMULUS TO DEVELOP. OVERALL... SHOULD BE A MOSTLY CLOUDY
DAY. RAPID CLEARING WILL OCCUR AFTER SUNSET SATURDAY. GIVEN A
FRESH SNOW COVER AND A LACK OF CLOUDS...WOULD NOT BE SURPRISED TO
SEE TEMPERATURES DROP BELOW GUIDANCE. IN OUR FAVOR WOULD BE A
CONTINUING WEST WIND IN SOME AREAS THAT WILL HELP KEEP THE
BOUNDARY LAYER BETTER MIXED. THOSE AREAS LACKING WIND WILL
UNDOUBTEDLY AGAIN SEE SUB-ZERO TEMPERATURES.
NORTHERLY FLOW WILL BE REINFORCED SUNDAY AS 100KT+ JET DIVES SOUTH
OUT OF SASKATCHEWAN. HIGH-AMPLITUDE RIDGE BUILDING ALONG THE WEST
COAST WILL KEEP THE FORECAST AREA IN CYCLONIC FLOW THROUGH AT LEAST
SUNDAY NIGHT. TAIL END OF SHORTWAVE ENERGY MOVING THROUGH THE
NORTHERN PLAINS WILL BRUSH THE EASTERN TWO-THIRDS OF THE FORECAST
AREA SUNDAY. THIS WILL BRING ADDITIONAL CLOUD COVER AND ANOTHER WEAK
SHOT OF COLDER AIR. GUSTY NORTHWEST WIND 20 TO 30 MPH WILL MAKE FOR
A RAW DAY EVEN WITH TEMPERATURES REBOUNDING FROM THE COLDER AIR OF
SATURDAY AND SATURDAY NIGHT. LOW TEMPERATURES SUNDAY NIGHT WILL BE
LARGELY DEPENDENT ON HOW MUCH CLOUD COVER REMAINS...ESPECIALLY OVER
THE EASTERN PLAINS OF WYOMING AND THE PANHANDLE.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 357 PM MST FRI NOV 14 2014
LOOKS LIKE DRY NORTHWEST FLOW ALOFT OVER THE FORECAST AREA FOR MUCH
OF THE EXTENDED. GRADIENT IS SUCH THAT BREEZY TO WINDY CONDITIONS
WILL PERSIST EARLY IN THE EXTENDED PERIOD. SHORTWAVE RIDGE ALOFT
DEPICTED FOR WEDNESDAY AND THURSDAY WITH WARMER TEMPERATURES. CANNOT
RULE OUT A FEW SNOW SHOWERS OVER THE SNOWY AND SIERRA MADRE
RANGES...POSSIBLY MORE SO FRIDAY WITH PASSAGE OF DEEPENING MID LEVEL
TROUGH. WILL HAVE TO SEE HOW THIS TROUGH OR SHORTWAVE EVOLVES FOR
LATE THURSDAY NIGHT INTO FRIDAY...BUT NO SIGNIFICANT STORM SYSTEMS
DURING THIS PERIOD. TEMPERATURES SHOULD BE AROUND NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1023 PM MST FRI NOV 14 2014
BASED 06Z TERMINAL FORECASTS OFF THE LATEST HRRR FORECAST. STARTED
LOWERING FLIGHT CONDITIONS A LITTLE EARLIER. CURRENT MOSAIC RADAR
SHOWING SNOW SHOWERS MOVING INTO CARBON COUNTY...SO KRWL SHOULD BE
COMING DOWN SOON. MORNING HOURS THROUGH 18Z WILL SEE THE MOST
WIDESPREAD IFR/LIFR CONDITIONS ACROSS SOUTHEAST WYOMING AND
NEBRASKA PANHANDLE WITH IMPROVING CONDITIONS AFTERWARDS.
&&
.FIRE WEATHER...
ISSUED AT 357 PM MST FRI NOV 14 2014
NO FIRE WEATHER CONCERNS THROUGH THIS WEEKEND. ANOTHER ARCTIC SYSTEM
WILL BRING SNOW ACROSS MOST AREAS THROUGH SATURDAY. SEVERAL INCHES
OF SNOW WILL ACCUMULATE...ESPECIALLY IN THE HIGHER ELEVATIONS OF
SOUTHERN WYOMING. THIS SNOW WILL BE FOLLOWED BY BRISK SURFACE WIND
AND COLD TEMPERATURES SUNDAY INTO SUNDAY NIGHT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 11 AM MST SATURDAY FOR WYZ101>103-
112-114.
WINTER WEATHER ADVISORY UNTIL 1 PM MST SATURDAY FOR WYZ104>106-
109>111-113-115>117.
NE...WINTER WEATHER ADVISORY UNTIL 11 AM MST SATURDAY FOR NEZ002-095.
&&
$$
UPDATE...CAH
SHORT TERM...RIW/ZF
LONG TERM...RIW/CAH
AVIATION...GCC
FIRE WEATHER...RIW/ZF
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
934 PM MST FRI NOV 14 2014
.UPDATE...
ISSUED AT 934 PM MST FRI NOV 14 2014
04Z SFC ANALYSIS SHOWS COLD FRONT LOCATED FROM AROUND GUERNSEY
EAST TO BETWEEN ALLIANCE AND HEMINGFORD. NORTH OF THE FRONT
TEMPERATURES HAVE TUMBLED INTO THE TEENS...WITH 20S AND EVEN SOME
30S REMAINING SOUTH OF THE FRONT ALONG THE I-80 CORRIDOR. ALTHOUGH
AREA RADAR BEAMS ARE OVERSHOOTING MUCH OF THE SNOW...WEBCAMS
CONFIRM THAT SNOW WAS FALLING IN AREAS FROM GLENROCK EAST TO
DOUGLAS...HARRISON AND CHADRON. ALTHOUGH ACCUMULATIONS APPEAR TO
BE RELATIVELY LIGHT THUS FAR...PERHAPS UP TO AN INCH IN A FEW
AREAS. BOTH 00Z NAM/GFS HAVE A GOOD HANDLE ON THIS 1-2 INCH SNOW
BAND IN THIS AREA THRU MIDNIGHT. FRONT WILL SHIFT SOUTH OF THE
CWFA THRU THE MORNING HOURS SATURDAY...CARRYING BEST FRONTAL
FORCING WITH IT. AS SUCH...BAND OF HEAVIER SNOW WILL SPREAD SOUTH
INTO THE REMAINDER OF THE AREA BY SUNRISE OR SHORTLY THEREAFTER.
SNOW WILL BE OUT OF THE AREA BY EARLY AFTERNOON. DIDNT NEED TO
MAKE ANY CHANGES TO CURRENT HIGHLIGHT PACKAGES...ALTHOUGH DID
ADJUST SNOWFALL ACCUMS SLIGHTLY...DOWNWARD IN THE NORTH PLATTE
RIVER VALLEY AND PERHAPS SLIGHTLY LESS ELSEWHERE AS WELL. ADDED
BLOWING SNOW TO THE FORECAST AS WELL AS POST-FRONTAL NORTHERLIES
WILL GUST TO 25-30 MPH AT TIMES...ESPECIALLY TOMORROW AFTERNOON.
THE COMBINATION OF WINDS...SNOW AND SUB-ZERO WIND CHILLS WILL NOT
MAKE FOR A DAY TO SPEND MUCH TIME OUTDOORS ON SATURDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 357 PM MST FRI NOV 14 2014
COLD FRONT POISED JUST TO THE NORTH OF THE FORECAST AREA THIS
AFTERNOON. UPPER LEVEL WESTERLY FLOW PARALLELING THE FRONT AND
KEEPING IT FROM MAKING MUCH PROGRESS TO THE SOUTH. SNOW SHOULD BEGIN
SPREADING EAST ACROSS CONVERSE/NIOBRARA COUNTIES BETWEEN 00Z-03Z/SAT
AND INTO DAWES AND NORTHERN SIOUX COUNTIES IN THE NEBRASKA PANHANDLE
BETWEEN 03Z-05Z/SAT. BOTH THE NAM12 AND HRRR KEEP THE SNOW CONFINED
TO THESE AREAS THROUGH 06Z/SAT. ABOUT THAT TIME...MORE ROBUST BAND
OF SNOW WILL BEGIN TO DEVELOP OVER CARBON COUNTY...ESPECIALLY ALONG
THE INTERSTATE 80 CORRIDOR AND THE MEDICINE BOW AND SIERRA MADRE
RANGES. STRONGER FRONTAL SURGE COMES AFTER ABOUT 08Z/SAT AND PUSHES
TO THE SOUTHERN BORDER OF THE FORECAST AREA BY 13Z/SAT.
BEST SNOWFALL ALONG AND EAST OF I-25 SHOULD COME WITH AND SHORTLY
BEHIND THE FRONTAL PASSAGE. PLATTE...GOSHEN...AND LARAMIE COUNTIES
ALONG WITH THE REMAINDER OF THE PANHANDLE SHOULD SEE 1 TO 3 INCH
AMOUNTS. FRONTOGENETIC FORCING DOES FAVOR SOME ENHANCED LIFT IN
LARAMIE COUNTY WHERE IMPACTS COULD STILL NECESSITATE AN UPGRADE TO A
WINTER WEATHER ADVISORY. THE EVENING SHIFT WILL NEED TO MONITOR
TRENDS FROM 00Z OUTPUT CLOSELY. IN ADDITION TO THE
SNOW...NORTHERLY WIND OF 15 TO 30 MPH WILL PREVAIL FOLLOWING COLD
FRONTAL PASSAGE. ELSEWHERE...ADVISORIES LOOK TO BE IN GOOD SHAPE
WITH FORECAST STILL ON THE CORRECT TRACK. AIRMASS SLOWLY DRIES
AFTER 18Z/SAT BUT ANY SUN WILL JUST ALLOW FOR COLD AIR
STRATOCUMULUS TO DEVELOP. OVERALL... SHOULD BE A MOSTLY CLOUDY
DAY. RAPID CLEARING WILL OCCUR AFTER SUNSET SATURDAY. GIVEN A
FRESH SNOW COVER AND A LACK OF CLOUDS...WOULD NOT BE SURPRISED TO
SEE TEMPERATURES DROP BELOW GUIDANCE. IN OUR FAVOR WOULD BE A
CONTINUING WEST WIND IN SOME AREAS THAT WILL HELP KEEP THE
BOUNDARY LAYER BETTER MIXED. THOSE AREAS LACKING WIND WILL
UNDOUBTEDLY AGAIN SEE SUB-ZERO TEMPERATURES.
NORTHERLY FLOW WILL BE REINFORCED SUNDAY AS 100KT+ JET DIVES SOUTH
OUT OF SASKATCHEWAN. HIGH-AMPLITUDE RIDGE BUILDING ALONG THE WEST
COAST WILL KEEP THE FORECAST AREA IN CYCLONIC FLOW THROUGH AT LEAST
SUNDAY NIGHT. TAIL END OF SHORTWAVE ENERGY MOVING THROUGH THE
NORTHERN PLAINS WILL BRUSH THE EASTERN TWO-THIRDS OF THE FORECAST
AREA SUNDAY. THIS WILL BRING ADDITIONAL CLOUD COVER AND ANOTHER WEAK
SHOT OF COLDER AIR. GUSTY NORTHWEST WIND 20 TO 30 MPH WILL MAKE FOR
A RAW DAY EVEN WITH TEMPERATURES REBOUNDING FROM THE COLDER AIR OF
SATURDAY AND SATURDAY NIGHT. LOW TEMPERATURES SUNDAY NIGHT WILL BE
LARGELY DEPENDENT ON HOW MUCH CLOUD COVER REMAINS...ESPECIALLY OVER
THE EASTERN PLAINS OF WYOMING AND THE PANHANDLE.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 357 PM MST FRI NOV 14 2014
LOOKS LIKE DRY NORTHWEST FLOW ALOFT OVER THE FORECAST AREA FOR MUCH
OF THE EXTENDED. GRADIENT IS SUCH THAT BREEZY TO WINDY CONDITIONS
WILL PERSIST EARLY IN THE EXTENDED PERIOD. SHORTWAVE RIDGE ALOFT
DEPICTED FOR WEDNESDAY AND THURSDAY WITH WARMER TEMPERATURES. CANNOT
RULE OUT A FEW SNOW SHOWERS OVER THE SNOWY AND SIERRA MADRE
RANGES...POSSIBLY MORE SO FRIDAY WITH PASSAGE OF DEEPENING MID LEVEL
TROUGH. WILL HAVE TO SEE HOW THIS TROUGH OR SHORTWAVE EVOLVES FOR
LATE THURSDAY NIGHT INTO FRIDAY...BUT NO SIGNIFICANT STORM SYSTEMS
DURING THIS PERIOD. TEMPERATURES SHOULD BE AROUND NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 357 PM MST FRI NOV 14 2014
VFR CONDITIONS EXPECTED AT ALL TERMINALS UNTIL ABOUT 02Z/SAT. FIRST
SURGE OF COLDER AIR WILL BEGIN TO GENERATE LIGHT SNOW GENERALLY
ALONG AND NORTH OF A KDGW-KCDR LINE BETWEEN 02Z-05Z. CONDITIONS WILL
BECOME MVFR AND EVENTUALLY IFR BY 06Z/SAT AT KCDR. KAIA AND KBFF
WILL BEGIN TO GET IN ON THE ACTION WITH MVFR EXPECTED AROUND 06Z/SAT
AS THE AREA OF LIGHT SNOW SAGS SLOWLY SOUTH. ABOUT THE SAME TIME...
APPEARS THAT A BETTER BAND OF SNOW WILL EXTEND EAST INTO CARBON
COUNTY AND IMPACT KRWL BY 08Z/SAT. A SECOND WAVE OF SNOW WILL THEN
DEVELOP AS A STRONGER FRONTAL SURGE TRAVERSES THE FORECAST AREA FROM
NORTH TO SOUTH FROM 08Z TO 13/SAT. GUSTY NORTHERLY WIND OF 15-30KTS
WILL ACCOMPANY AND FOLLOW FRONTAL PASSAGE. IFR AND LIFR CONDITIONS
WILL BE WIDESPREAD WITH THE HEAVIEST SNOWFALL LIKELY TO OCCUR
BETWEEN ABOUT 10Z-15Z/SAT. DRIER CONDITIONS SHOULD BEGIN TO PUSH
ACROSS THE FORECAST AREA FROM NORTH-TO-SOUTH BETWEEN 15Z-20Z/SAT.
THERE SHOULD BE ENOUGH COLD AIR ALOFT THAT ANY PARTIAL CLEARING WILL
ALLOW FOR STRATOCUMULUS TO FORM...ALTHOUGH CONDITIONS SHOULD BE VFR
AFTER ABOUT 19Z/SAT. MOUNTAIN OBSCURATIONS WILL BE WIDESPREAD FROM
SHORTLY AFTER 00Z/SAT UNTIL ABOUT 18Z/SAT. MOUNTAIN TOP OBSCURATIONS
WILL CONTINUE AFTER THAT TIME UNTIL SUNSET LATE SATURDAY
AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 357 PM MST FRI NOV 14 2014
NO FIRE WEATHER CONCERNS THROUGH THIS WEEKEND. ANOTHER ARCTIC SYSTEM
WILL BRING SNOW ACROSS MOST AREAS THROUGH SATURDAY. SEVERAL INCHES
OF SNOW WILL ACCUMULATE...ESPECIALLY IN THE HIGHER ELEVATIONS OF
SOUTHERN WYOMING. THIS SNOW WILL BE FOLLOWED BY BRISK SURFACE WIND
AND COLD TEMPERATURES SUNDAY INTO SUNDAY NIGHT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 11 AM MST SATURDAY FOR WYZ101>103-
112-114.
WINTER WEATHER ADVISORY UNTIL 1 PM MST SATURDAY FOR WYZ104>106-
109>111-113-115>117.
NE...WINTER WEATHER ADVISORY UNTIL 11 AM MST SATURDAY FOR NEZ002-095.
&&
$$
UPDATE...CAH
SHORT TERM...RIW/ZF
LONG TERM...RIW/CAH
AVIATION...RIW/CAH
FIRE WEATHER...RIW/ZF
AREA FORECAST DISCUSSION
NWS TAUNTON MA
348 AM EST MON NOV 17 2014
.SYNOPSIS...
LOW PRESSURE WILL INTENSIFY AS IT PASSES OVER SOUTHERN NEW
ENGLAND LATER TODAY...BRINGING RAIN TO THE REGION AND POSSIBLY
DAMAGING WINDS TO SOUTHEAST NEW ENGLAND. MAINLY DRY BUT
UNSEASONABLY COLD AND BLUSTERY WEATHER IS EXPECTED TUESDAY
THROUGH THE REST OF THIS WEEK. THERE IS JUST THE RISK FOR A FEW
FLURRIES/LIGHT SNOW SHOWERS WEDNESDAY NIGHT. APPEARS A SIGNIFICANT
WARMUP IS IN STORE FOR EARLY NEXT WEEK WITH A HIGH LIKELIHOOD IN
ABOVE NORMAL TEMPERATURES.
&&
.NEAR TERM /THROUGH TODAY/...
350 AM UPDATE...
PRECIPITATION SHIELD CONTINUES TO SPREAD N EARLY THIS MORNING...
VERY MUCH IN LINE WITH 13KM RAP TIMING. SEEING SEVERAL REPORTS OF
SNOW AND SLEET ON ITS LEADING EDGE DUE TO INITIAL WET BULB
COOLING AND LOW LEVEL NORTHERLY AGEOSTROPHIC FLOW...BUT RAP SHOWS
FAIRLY QUICK WARMING TAKING PLACE THROUGH DAYBREAK WHICH WILL
RESULT IN CHANGE TO RAIN ACROSS MOST OF AREA. EXCEPTION IS ACROSS
HIGHER TERRAIN OF W MA AND SW NH WHICH WILL TAKE A BIT LONGER...
SO WE WILL KEEP THE WINTER WEATHER ADVISORY POSTED. NOT LOOKING
FOR MUCH IN WAY OF SNOW OR ICE ACCUMULATION...BUT ENOUGH TO RESULT
IN SLIPPERY TRAVEL ESPECIALLY FOR THE FIRST PART OF THE MORNING
COMMUTE.
TEMPERATURES WILL BOTTOM OUT ACROSS INTERIOR THROUGH DAYBREAK DUE
TO WET BULB COOLING...BUT SHOULD REMAIN STEADY OR BEGIN TO RISE
SLOWLY CLOSER TO COAST AS SOUTHERLY FLOW GETS UNDERWAY.
MADE A FEW MINOR ADJUSTMENTS TO FORECAST BASED UPON 00Z MODELS
WHICH ARE OUTLINED BELOW. MAIN CONCERN NOW REVOLVES AROUND
DAMAGING WINDS AND HEAVY RAINFALL LATER TODAY AND THIS EVENING.
* STRONG/DAMAGING WINDS...
EXPANDED HIGH WIND WARNING TO INCLUDE MA S COAST AS WELL AS
EASTERN PLYMOUTH COUNTY. NAM/GFS SHOW AXIS OF LOW LEVEL JET
PASSING OVER CAPE COD AND ISLANDS CENTERED AROUND 00Z TUE. THESE
LOCATIONS ARE CLOSE ENOUGH IN WARM SECTOR TO INCREASE POTENTIAL
FOR 50-60KT WIND GUSTS ACROSS THESE AREAS IN ADDITION TO CAPE
COD...MARTHAS VINEYARD AND NANTUCKET. IN ADDITION...HIGH RES
MODELS SHOW STRONG POTENTIAL FOR LINE OF CONVECTION EARLY THIS
EVENING WHICH COULD PRODUCE DAMAGING WINDS AS WELL.
WIND ADVISORY WAS ALSO EXPANDED TO INCLUDE NW RI AND EASTERN MA
FROM METRO BOSTON TO CAPE ANN. THESE LOCATIONS SHOULD ALSO GET
INTO WARM SECTOR LATER THIS AFTERNOON WHICH WILL INCREASE
POTENTIAL FOR STRONG WIND GUSTS /40-45KT/.
* HEAVY RAINFALL...
WIDESPREAD 1 TO 2 INCHES OF RAIN IS EXPECTED ACROSS SOUTHERN NEW
ENGLAND...BUT HIGH-RES MODELS CONTINUE TO SHOW AXIS OF 2 TO 3
INCHES OF RAIN ACROSS RI AND SE MA WHICH MAY BE ASSOCIATED WITH
LINE OF CONVECTION EARLY THIS EVENING. THIS IS NOT EXPECTED TO
PRODUCE WIDESPREAD FLOODING...BUT COULD RESULT IN MINOR FLOODING
OF TYPICAL POOR DRAINAGE AREAS. CERTAINLY NEED TO KEEP AN EYE ON
ANY CONVECTIVE DEVELOPMENT AS THAT WOULD SIGNIFICANTLY INCREASE
POTENTIAL FOR FLOODING. FOR NOW CONFIDENCE IS NOT OVERLY HIGH IN
THAT OCCURRING.
HIGHS TODAY WILL RANGE FROM 40S ACROSS INTERIOR WHERE COOLER AIR
WILL BE LOCKED IN...WHILE LOCATIONS CLOSER TO COAST RISE INTO 50S
AND LOWER 60S LATE IN DAY. BLENDED NAM 2M TEMPERATURES TO MOS
GUIDANCE WHICH LOOKED A BIT TOO COOL.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/...
350 AM UPDATE...
RAIN ENDS QUICKLY FROM W TO E AS LOW PRESSURE DEPARTS SOUTHERN NEW
ENGLAND. DRYING SETS IN RAPIDLY OVERNIGHT WITH CLEARING SKIES
EXPECTED. TEMPERATURES ACROSS INTERIOR WILL DROP INTO THE 20S AND
LOWER 30S...WHICH COULD CAUSE SOME FREEZING OF LEFTOVER STANDING
WATER...BUT THERE SHOULD BE ENOUGH MIXING TO ALLOW W WINDS TO DRY
THINGS OUT. NOT AN ISSUE CLOSER TO COAST WHERE LOWS WILL REMAIN
ABOVE FREEZING.
COLDER AIR ARRIVES TUE ON BRISK W WINDS. THIS WILL MAINTAIN SOME
CLOUDINESS ACROSS W NEW ENGLAND WITH MORE SUNSHINE DUE TO
DOWNSLOPE WINDS CLOSER TO COAST...ALTHOUGH CLOUD STREETS SHOULD
ALSO FORM OFF COAST DUE TO COLDER AIR PASSING OVER MILDER OCEAN
SURFACE. HIGHS WILL TOP OUT IN 30S INTERIOR TO LOWER 40S NEAR
COAST.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
350 AM UPDATE
HIGHLIGHTS...
* DRY BUT UNSEASONABLY COLD TUE NIGHT INTO WED
* A FEW FLURRIES/LIGHT SNOW SHOWERS POSSIBLE WED NIGHT
* TEMPS TURN A BIT MILDER ON THU...BUT STILL BELOW NORMAL
* ANOTHER SHOT OF UNSEASONABLY COLD WEATHER FRI INTO SAT
* SIGNIFICANT WARMUP EARLY NEXT WEEK
DETAILS...
TUESDAY NIGHT AND WEDNESDAY...
ANOMALOUS UPPER LEVEL RIDGING INTO WESTERN NORTH AMERICA AND ALASKA
WILL FORCE THE POLAR JET SOUTH INTO THE EASTERN U.S. THIS WILL
RESULT IN MAINLY DRY...BUT UNSEASONABLY COLD/BLUSTERY WEATHER.
DESPITE WINDS NOT DECOUPLING TUE NIGHT...LOW TEMPS SHOULD BOTTOM OUT
IN THE UPPER TEENS TO MIDDLE 20S FOR MOST UNDER STRONG COLD
ADVECTION. WIND CHILL VALUES WILL BE DOWN IN THE SINGLE DIGITS
ACROSS THE INTERIOR AND 10 TO 15 DEGREES ALONG THE COASTAL PLAIN BY
DAYBREAK WED!
DESPITE PARTIAL SUNSHINE ON WED...850 MB TEMPS AROUND -14C WILL
RESULT IN HIGH TEMPS 15 TO 20 DEGREES BELOW NORMAL. HIGH TEMPS
SHOULD ONLY RECOVER TO AROUND 30 ACROSS THE HIGHER TERRAIN AND
MIDDLE 30S ON THE COASTAL PLAIN. WIND GUSTS OF 25 TO 35 MPH WILL
MAKE IT FEEL EVEN COLDER...CERTAINLY MORE LIKE JANUARY THAN NOVEMBER.
WEDNESDAY NIGHT AND THURSDAY...
MID LEVEL WARM ADVECTION WILL DEVELOP AHEAD OF THE NEXT COLD FRONT.
GIVE THE COLD DOME IN PLACE...COULD SEE A BRIEF PERIOD OF
FLURRIES/LIGHT SNOW SHOWERS WED NIGHT AS THIS WARMER AIR OVER RUNS
IT. BOUNDARY LAYER SHOULD BE COLD ENOUGH FOR MAINLY LIGHT SNOW
SHOWERS/FLURRIES...EXCEPT PERHAPS ACROSS FAR SOUTHEAST NEW ENGLAND
COAST. CERTAINLY DO NOT EXPECT MUCH SNOW...BUT A FEW NEIGHBORHOODS
COULD RECEIVE A COATING. ANY OF THIS ACTIVITY SHOULD EXIT THE
REGION BY MID MORNING ON THU. OTHERWISE...SHOULD SEE PARTIAL
SUNSHINE DEVELOP BY THU AFTERNOON. HIGHS WILL BE MILDER THAN TUE
AND WED...RECOVERING TO THE UPPER 30S ACROSS THE HIGHER TERRAIN TO
THE LOWER TO MIDDLE 40S ON THE COASTAL PLAIN.
FRIDAY AND SATURDAY...
UNSEASONABLY COLD AIR WORKS BACK INTO THE REGION FRI INTO SAT BEHIND
THE COLD FRONT. HIGH TEMPS SHOULD MAINLY BE IN THE 30S...TO THE
LOWER 40S ON FRI. SAT LOOKS VERY COLD WITH HIGHS NOT GETTING OUT OF
THE 30S. IN FACT...IF THE ECMWF IS RIGHT HIGH TEMPS MAY NOT BREAK
FREEZING ALONG THE COASTAL PLAIN! NOT SURE IF IT WILL BE THAT
EXTREME...BUT THIS SHOT OF COLD AIR ALSO LOOKS VERY IMPRESSIVE.
SUNDAY AND MONDAY...
HIGH PRESSURE MOVES OFF THE COAST ON SUNDAY ALLOWING A SOUTHWEST
FLOW OF MILDER AIR TO WORK INTO THE REGION. HIGHS SHOULD RECOVER
WELL INTO THE 40S...TO PERHAPS NEAR 50 ALONG THE FAR SOUTHEAST NEW
ENGLAND COAST. MOST OF THE DAY SHOULD BE DRY...BUT CHANCES FOR
SHOWERS WILL INCREASE SUN NIGHT AND MON AS LOW PRESSURE PASSES TO
OUR NORTHWEST ALLOWING LOW LEVEL MOISTURE TO STREAM NORTHWARD. THIS
SHOULD RESULT IN WELL ABOVE NORMAL TEMPS BY NEXT MON...SO BIG
CHANGES ARE EXPECTED BY EARLY NEXT WEEK.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
350 AM UPDATE...MODERATE CONFIDENCE.
MVFR CIGS NEAR S COAST SLOWLY EXPAND INLAND EARLY THIS MORNING
WITH MOST SITES LOWERING TO MVFR BY 12Z AS RAIN SPREADS INTO
SOUTHERN NEW ENGLAND. MAIN AREA OF -FZRA/-SN/-PL CONTINUES TO BE
ON NORTHERN EDGE OF PRECIPITATION SHIELD ACROSS W MA AND SW
NH...BUT THESE AREAS WILL TRANSITION TO RAIN DURING MORNING.
CONDITIONS LOWER FURTHER TO IFR BY EARLY AFTERNOON IN RAIN AND
FOG. INCREASING LOW LEVEL JET /75KT AT 3KFT/ WILL BRING LLWS TO
MUCH OF RI AND SE MA DURING AFTERNOON AND EVENING. SURFACE WIND
GUSTS 50-60KT POSSIBLE AROUND CAPE COD AND ISLANDS AND TO 45KT
ACROSS RI AND EASTERN MA. LIGHTER SURFACE WINDS FARTHER INLAND BUT
LLWS STILL A CONCERN WITH 40-45KT AT 3KFT.
POTENTIAL FOR EMBEDDED TSTMS S OF I-90 LATE THIS AFTERNOON AND
EARLY THIS EVENING...OR EVEN NARROW LINE OF TSTMS...BUT NOT
INCLUDED IN TAFS DUE TO LOW PROBABILITY.
CONDITIONS IMPROVE RAPIDLY TO VFR FROM W TO E BETWEEN 03Z AND 08Z
TUE AS WINDS SHIFT TO W. VFR TUE WITH W WINDS GUSTING TO 30KT.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. CONDITIONS MAY LOWER A
BIT FASTER THAN INDICATED THIS MORNING. MORE CONFIDENT ON WIND
TRENDS.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. SOME UNCERTAINTY AS TO
HOW QUICKLY CONDITIONS LOWER THIS MORNING. PRECIPITATION TYPE ALL
RAIN.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
HIGH CONFIDENCE IN MAINLY VFR CONDITIONS OVER THIS TIME PERIOD.
HOWEVER...BRIEF PERIODS OF MVFR CONDITIONS ARE POSSIBLE FROM TIME TO
TIME. THE BEST SHOT FOR THIS IS WED NIGHT IN A FEW LIGHT SNOW
SHOWERS/FLURRIES. WEST TO SOUTHWEST WINDS WILL GUST AT TIMES
BETWEEN 20 AND 30 KNOTS THROUGH THU AND FROM THE WEST NORTHWEST ON
FRI.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
* DANGEROUS CONDITIONS THIS AFTERNOON AND TONIGHT *
350 AM UPDATE...MODERATE CONFIDENCE.
EXPANDED STORM WARNINGS TO INCLUDE MORE OF S COASTAL BAYS AND
SOUNDS. ONSET OF GALES IS AROUND MIDDAY ON SOUTHERN WATERS AND
EARLY THIS AFTERNOON ON EASTERN WATERS...WITH STRONGEST WINDS
CENTERED FEW HOURS AROUND 7 PM TONIGHT.
PERIODS OF RAIN EXPECTED TODAY BUT THERE IS ALSO POSSIBILITY OF
EMBEDDED THUNDERSTORMS...OR A NARROW LINE OF STORMS...LATER THIS
AFTERNOON AND THIS EVENING.
IN RESPONSE TO INCREASING WINDS...SEAS WILL BUILD RAPIDLY THIS
AFTERNOON WITH 12 FT SEAS ON OUTER WATERS THIS EVENING.
WINDS SHIFT TO W LATER TONIGHT AS LOW PRESSURE EXITS REGION. WINDS
WILL GRADUALLY DIMINISH BUT REMAIN GUSTY...AT LEAST 25-30KT...AND
SEAS WILL REMAIN ROUGH.
BRISK W WINDS GUSTING TO 30-35KT EXPECTED TUE AS HIGH PRESSURE
BUILDS INTO NEW ENGLAND.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
TUESDAY NIGHT AND WEDNESDAY...HIGH CONFIDENCE. STRONG COLD
ADVECTION OVER THE RELATIVELY MILD OCEAN WILL RESULT IN GALE FORCE
WEST TO SOUTHWEST WIND GUSTS TUE NIGHT INTO WED MORNING OVER THE
OPEN WATERS. WINDS PROBABLY DROP BACK TO SMALL CRAFT ADVISORY
THRESHOLDS WED AFTERNOON AS PRESSURE GRADIENT WEAKENS A BIT. SEAS 6
TO 10 FEET ACROSS THE OUTER-WATERS WILL GRADUALLY DIMINISH WED
AFTERNOON.
WEDNESDAY NIGHT AND THURSDAY...MODERATE TO HIGH CONFIDENCE. WARM
ADVECTION DEVELOPS AHEAD OF THE NEXT COLD FRONT. HOWEVER...THE
AIRMASS WILL STILL BE COLDER THAN THE RELATIVELY MILD OCEAN AND
SUPPORT GOOD MIXING. THEREFORE...EXPECT STRONG SCA TO GALE FORCE
WIND GUSTS OVER THE OPEN WATERS. STRONGEST WINDS EXPECTED OVER THE
SOUTHERN WATERS WITH SEAS BUILDING BACK BETWEEN 6 AND 10 FEET IN
THIS REGION.
FRIDAY...MODERATE TO HIGH CONFIDENCE. STRONG SMALL CRAFT TO GALE
FORCE WEST TO NORTHWEST WIND GUSTS EXPECTED IN THE COLD AIR
ADVECTION PATTERN BEHIND THE NEXT COLD FRONT.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MAZ002>004-008>010-026.
WIND ADVISORY FROM 3 PM THIS AFTERNOON TO 10 PM EST THIS
EVENING FOR MAZ007-013>018.
HIGH WIND WARNING FROM 3 PM THIS AFTERNOON TO 11 PM EST THIS
EVENING FOR MAZ019>024.
NH...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
NHZ011-012-015.
RI...WIND ADVISORY FROM 3 PM THIS AFTERNOON TO 10 PM EST THIS
EVENING FOR RIZ001>008.
MARINE...STORM WARNING FROM 3 PM THIS AFTERNOON TO 1 AM EST TUESDAY FOR
ANZ231>235.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 1 AM EST TUESDAY FOR
ANZ230-236.
GALE WARNING FROM NOON TODAY TO 1 AM EST TUESDAY FOR ANZ237-
251.
GALE WARNING FROM NOON TODAY TO 5 AM EST TUESDAY FOR ANZ250-
256.
STORM WARNING FROM 3 PM THIS AFTERNOON TO 3 AM EST TUESDAY FOR
ANZ254-255.
&&
$$
SYNOPSIS...FRANK/JWD
NEAR TERM...JWD
SHORT TERM...JWD
LONG TERM...FRANK
AVIATION...FRANK/JWD
MARINE...FRANK/JWD
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
331 AM EST MON NOV 17 2014
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM...LONG TERM AND AVIATION
SECTIONS HAVE BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 331 AM EST MON NOV 17 2014
WIDESPREAD SNOW WILL END THIS MORNING WITH SCATTERED SNOW SHOWERS
INTO THE EVENING AS MUCH COLDER AIR SPREADS INTO THE OHIO VALLEY.
VERY COLD WEATHER WILL CONTINUE THROUGH MIDWEEK...WITH CHANCES FOR
SNOW AGAIN ON WEDNESDAY AS A WEAK UPPER LEVEL WAVE PASSES THROUGH
THE REGION. LOW PRESSURE TRACKING INTO THE REGION OVER THE WEEKEND
WILL BRING A RETURN TO UNSETTLED WEATHER ALONG WITH WARMER
TEMPERATURES.
&&
.NEAR TERM /TODAY/...
ISSUED AT 331 AM EST MON NOV 17 2014
STEADY SNOWFALL CONTINUES ALONG AND SOUTHEAST OF A TERRE HAUTE-INDY
METRO-MUNCIE LINE AS OF 08Z. BACK EDGE OF THE PRECIP SHIELD HAS
BACKPEDALED NORTHWEST OVER THE LAST 2-3 HOURS AS THE SHARP UPPER
WAVE QUICKLY TRACKS INTO THE LOWER MISSISSIPPI VALLEY. TEMPS WERE
GENERALLY IN THE 20S AND FALLING WITH THE INITIAL ARRIVAL OF THE
ARCTIC AIRMASS.
INITIAL ISSUE FOCUSES ON THE SNOW CONTINUING EARLY THIS MORNING WITH
ITS DEPARTURE OFF TO THE EAST BETWEEN 12-15Z. DESPITE THE PIVOT BACK
TO THE WEST OF THE PRECIP SHIELD...DO NOT EXPECT IT TO SHIFT MUCH
FURTHER NORTHWEST FROM ITS CURRENT POSITION AS UPPER LEVEL ENERGY IS
QUICKLY APPROACHING FROM THE SOUTHWEST WHILE THE MAIN SURFACE LOW
TRACKS INTO NORTHERN GEORGIA. HRRR AND THE WRF BOTH HAVE A NICE
HANDLE ON THE LOCATION OF THE SNOWFALL AND EXPECTED EVOLUTION
THROUGH DAYBREAK. SNOW WILL BEGIN TO SHIFT EAST AFTER 09-10Z...WITH
PRECIP ENDING OVER FAR EASTERN COUNTIES BY 14-15Z. WITH THE
POTENTIAL FOR ANOTHER INCH OR TWO OF ADDITIONAL ACCUM OVER THE
SOUTHEAST HALF OF THE FORECAST AREA...WILL CONTINUE WITH THE
ADVISORY IN ITS CURRENT STATE THROUGH 14Z. HEAVIER SNOWFALL WILL
REMAIN SOUTHEAST OF THE INDY METRO...BUT STILL QUITE POSSIBLE TO
TACK ON ANOTHER HALF INCH OR SO IN THE CITY BEFORE SNOW ENDS.
FURTHER NORTHWEST...EXPECT LITTLE MORE THAN FLURRIES OVER THE NEXT
FEW HOURS.
DRIER AIR WILL WRAP INTO THE REGION BEHIND THE SNOWFALL LATER THIS
MORNING AND MAY EVEN BRING A FEW PEAKS OF SUNSHINE THROUGH MIDDAY.
COLD POOL BEGINS TO SETTLE OVER THE REGION DURING THE AFTERNOON AS
THE UPPER LOW PINWHEELS INTO THE NORTHERN GREAT LAKES. AS HAS BEEN
DISCUSSED OVER THE LAST FEW DAYS...POTENTIAL FOR SCATTERED SNOW
SHOWERS TO REDEVELOP THIS AFTERNOON AND EVENING. MODELS IN GENERAL
TEND TO STRUGGLE IN THIS SETUP AND OFTEN UNDERDO THE SNOW POTENTIAL
BECAUSE THEY DO NOT CAPTURE THE MESOSCALE FEATURES WELL. THE WRF
DOES A BETTER JOB IN THIS REGARD AND NOW THAT WE ARE WITHIN ITS
WINDOW...IT IS SUPPORTING POTENTIAL FOR SCATTERED CONVECTIVE SNOW
SHOWERS/SQUALLS LATER THIS AFTERNOON...AND THESE COULD CAUSE SOME
PROBLEMS OVER THE REGION.
PLENTY OF MID LEVEL ENERGY ROTATING AROUND THE BASE OF THE UPPER LOW
AND THROUGH THE REGION. THIS COMBINED WITH INTENSIFYING COLD
ADVECTION AND SHALLOW INSTABILITY WITH STEEPENING LAPSE RATES TO
850MB SUPPORT CONVECTIVE SNOW SHOWERS. WITH WIND GUSTS STEADILY
STRENGTHENING TO AROUND 30MPH THIS AFTERNOON...THESE SNOW
SHOWERS/SQUALLS HAVE THE POTENTIAL TO CREATE A GREATER IMPACT ON
TRAVEL THAN THE SNOW EXPERIENCED SUNDAY NIGHT AND EARLY THIS
MORNING. WHILE SNOWFALL WILL BE ONLY A DUSTING TO A FEW TENTHS OF AN
INCH AT BEST...THE SNOW WILL BE DRIER AND MUCH EASIER TO BLOW AROUND
WITH THE POTENTIAL FOR LOCALLY REDUCED VISIBILITIES IN HEAVIER SNOW
SHOWERS. AS CRAZY AS THIS SOUNDS...HAVE A GROWING CONCERN THAT THE LATE
AFTERNOON/EVENING RUSH HOUR COULD BE MORE GREATLY IMPACTED THAN THIS
MORNING. WILL BE INTRODUCING AN SPS TO HIGHLIGHT THESE THREATS FOR
LATER TODAY.
TEMPS...HIGHS ARE TRICKY FOR TODAY CONSIDERING THEY ARE LARGELY
LOWER THAN CURRENT READINGS THIS MORNING. MAY SEE A BRIEF RISE IN
TEMPS THROUGH MIDDAY WITH FALLING TEMPS THEREAFTER AS THE STRONGER
COLD ADVECTION ARRIVES. A MOS BLEND WAS REASONABLE FOR HIGHS...THEN
USED A MIX OF NAM/LAMP DATA FOR THE FALLING TEMPS THIS AFTERNOON.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 331 AM EST MON NOV 17 2014
FORECAST CHALLENGES FOCUS ON TEMPS THROUGH THE PERIOD AND SNOW
CHANCES...PRIMARILY WEDNESDAY.
AN EVEN STRONGER BLAST OF COLD AIR OF POLAR ORIGIN POISED TO
OVERSPREAD THE OHIO VALLEY AND GREAT LAKES FOR MOST OF THE SHORT
TERM. AFOREMENTIONED SCATTERED SNOW SHOWERS WILL BE ONGOING THIS
EVENING...LIKELY NOT DIMINISHING IN INTENSITY AND COVERAGE UNTIL
CLOSER TO MIDNIGHT. WILL MAINTAIN SCATTERED FLURRIES OVERNIGHT WITH
STILL PLENTY OF FORCING ALOFT AND WILL HAVE TO MONITOR AS COULD EVEN
SEE A FEW SNOW SHOWERS LINGER WELL INTO THE OVERNIGHT.
UPPER TROUGH AND COLD POOL ALOFT CENTERED OVER THE REGION EARLY
TUESDAY...GRADUALLY LIFTING OUT BY LATE TUESDAY AS THE UPPER LOW
SHIFTS EAST INTO QUEBEC. WILL MAINTAIN A MENTION OF SCATTERED
FLURRIES INTO THE AFTERNOON...ENDING FROM WEST TO EAST AS FORCING
ALOFT WEAKENS. WEAK SURFACE RIDGING WILL QUICKLY TRACK ACROSS THE
REGION TUESDAY NIGHT BRINGING A BRIEF PERIOD OF CLEARING BEFORE
CLOUDS INCREASE IN ADVANCE OF ANOTHER APPROACHING WAVE ALOFT FROM
THE NORTHWEST.
THE UPPER WAVE WILL SWING ACROSS THE LOWER GREAT LAKES WEDNESDAY
WITH LIGHT SNOW SHOWERS IMPACTING PRIMARILY THE NORTHERN HALF OF THE
FORECAST AREA. COULD SEE SOME VERY LIGHT ACCUMS NORTH OF I-70 FROM A
DUSTING UP TO CLOSE TO AN INCH IN FAR NORTHERN COUNTIES BY LATE DAY
WEDNESDAY. BUMPED UP TO CHANCE POPS IN THE NORTH WEDNESDAY. SKIES
WILL CLEAR WEDNESDAY NIGHT AS HIGH PRESSURE REESTABLISHES ALONG WITH
A RENEWED SURGE OF COLDER AIR.
TEMPS...DEFINITELY THE BIG STORY OF THE SHORT TERM. UNDERCUT MOS
GUIDANCE FOR LOWS TONIGHT WITH SNOWCOVER AND 850MB TEMPS BOTTOMING
OUT AT -21 TO -20C BY TUESDAY MORNING. THINK MOST LOCATIONS GET INTO
THE SINGLE DIGITS. ONLY MODEST RECOVERY FOR TUESDAY AS HIGHS WILL
END UP RIGHT AROUND 20. LEANED CLOSER TO COOLER END OF GUIDANCE THE
REST OF THE WAY...WITH HIGHS RECOVERING INTO THE LOWER/MID 30S FOR
WEDNESDAY.
INDY RECORDS FOR TUESDAY...RECORD LOW IS 5 (1880) AND RECORD LOW MAX
TEMP IS 20 (1880). POTENTIAL FOR THE FIRST SINGLE DIGIT LOW IN
NOVEMBER SINCE 11/30/1976.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ISSUED AT 331 AM EST MON NOV 17 2014
ENSEMBLES SUGGEST A DEEP UPPER TROUGH INITIALLY OVER THE EASTERN
PARTS OF THE COUNTRY WILL BE LIFTING OFF TO THE NORTHEAST BY LATE IN
THE WEEK...LEAVING A MORE ZONAL FLOW OVER THE LOCAL AREA.
THE NEXT SYSTEM THAT MAY AFFECT THE AREA DURING THIS PERIOD WILL BE
A DISTURBANCE OF PACIFIC ORIGIN. THERE IS STILL QUITE A BIT OF
SPREAD AMONG THE ENSEMBLES AS TO THE TIMING OF THIS FEATURE...FROM
AS EARLY AS FRIDAY NIGHT TO AS LATE AS SATURDAY NIGHT OR SUNDAY. FOR
NOW...WILL BROADBRUSH POPS STARTING FRIDAY NIGHT THROUGH NEXT
SUNDAY. THERE MAY STILL BE ENOUGH RESIDUAL COLD AIR AROUND FOR MIXED
PRECIPITATION OVER PARTS OF THE AREA FRIDAY NIGHT THROUGH SATURDAY
NIGHT...BUT ENSEMBLES SUGGEST LITTLE THREAT FOR SIGNIFICANT
ACCUMULATIONS AT THIS TIME.
&&
.AVIATION /DISCUSSION FOR THE 170900Z TAF UPDATE/...
ISSUED AT 331 AM EST MON NOV 17 2014
NORTHWEST EDGE OF SNOW SHIELD JUST SCRAPING THE KIND VICINITY.
EXPECTING THE SNOW TO END AT KIND OVER THE NEXT HOUR.
OTHERWISE...IFR CEILINGS LIFTING INTO AN MVFR DECK AROUND 012-015
OVER THE WESTERN PARTS OF THE STATE AT THIS TIME...SO EXPECTING
CEILINGS TO RISE ABOVE IFR IN THE NEXT FEW HOURS.
PREVIOUS DISCUSSION FOLLOWS.
SNOW HAS ENDED AT KLAF AND AND KHUF...AND IS MAINLY CONFINED TO
KIND AND KBMG AT THIS TIME. CONDITIONS HAVE ALREADY IMPROVED TO
MVFR CATEGORY AT KHUF...BUT IFR CEILINGS WILL LINGER AT KLAF A BIT
LONGER. ELSEWHERE...MVFR CONDITIONS SHOULD RETURN TO KIND AND KBMG
AFTER MON 08Z WHEN SNOW INTENSITY WEAKENS. HOWEVER...DID HOLD
ONTO MENTION OF LIGHT SNOW SHOWERS THROUGH DAYBREAK AT THOSE 2
SITES WHICH ARE CLOSER TO THE NEXT WAVE.
VFR CONDITIONS SHOULD BE THE PREVAILING FLIGHT CATEGORY BY MON 14Z
AT ALL TAF SITES. HOWEVER...STRONG WEST WINDS WILL THEN BECOME
AN ISSUE...BLOWING SNOW AROUND. SUSTAINED SPEEDS WILL RANGE
BETWEEN 12 TO 15 KTS WITH GUSTS UP TO 25 KTS THROUGH THE END OF
TAF PERIOD AT KLAF/KIND/KHUF.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
INZ037>042-045>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...TDUD/JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1108 PM CST Sun Nov 16 2014
.UPDATE...
Issued at 1105 PM CST SUN NOV 16 2014
Updated Aviation discussion for 06Z TAF Issuance.
UPDATE Issued at 937 CST SUN NOV 16 2014
Making some minor adjustments to snow totals, but overall the
package looks good. The heaviest precipitation band has set up
from Stoddard county in SEMO to the northwest half of McCracken
towards Henderson county to Spencer county. This has pretty much
been the story so far this evening.
The HRRR model depicts things pretty well and we expect that
heavier band to stay in place through about midnight, then the
band should actually shift to the north a bit as the main short
wave gets closer. This band then slides southeast through the
early morning hours.
Already had some 2+ inch amounts along the Wabash/Ohio River
areas and once the temperature drops to 32 the accumulations
start. The 32 degree line essentially runs from EVV to PAH and is
slowly moving southeast.
&&
.SHORT TERM...(Tonight through Tuesday night)
Issued at 134 PM CST SUN NOV 16 2014
Confidence in increasing that there will be a fairly significant
snow event along the Ohio River and back into extreme southeast
Missouri. 12z GFS, in particular has honed in on a precip max
along that axis for several runs now, and thermal profiles suggest
that axis will likely correspond to where the initial snow/mix line
will set up early this evening. Expecting very close to .40 inches
liquid QPF, so will increase snow projections into the 3-5 inch
range. Have already upgraded to warning headlines along the Ohio
River for tonight. See no need for further adjustments at this
time. Still looking for all snow northwest of the warning area,
but QPF will likely not be quite as high. Will need to monitor
though, because have already heard of at least one report of 3.5
inches out to our west in the SGF CWA. Will stick with the
advisory in our nw half for the time being. Still lots of
uncertainties concerning precip type and the timing of the
transition from rain/sleet over to snow, most likely around
or after the midnight time frame far southeast locations. Believe
there will still be enough moisture left after the transition
over to snow later tonight for an inch or so to accumulate before
the precip comes to an end around dawn Monday. Thus, will
continue with the Winter Weather Advisory for the rest of the CWA
surrounding the warning area.
Next big story lies with the bitterly cold Arctic air that will
follow early in the week. Blustery winds gusting over 20 mph on
Monday may cause some blowing or drifting of any snow that is on
the ground and hold daytime temps nearly steady in the 20s. Will
then challenge record low temps Monday night as reading fall down
into the 10 to 15 degree range. Wind chill values could be near
zero by the time many awake and head out on Tuesday.
.LONG TERM...(Wednesday through Sunday)
Issued at 320 PM CST SUN NOV 16 2014
Surface high pressure over the southeast U.S. will keep our region
dry Tuesday night into Wednesday, and a return of south to southwest
winds will help temperatures moderate a little from the very cold
temperatures early in the work week. Models continue to show a weak
dry cold front moving across the middle Mississippi and lower Ohio
valleys Wednesday into Wednesday night. This will bring another
shot of colder air, with highs Thursday and Friday again dropping
back a couple to several degrees.
For Thursday night and beyond, models continue to be all over the
place. GFS brings in a shot of precip late Thursday into Thursday
night, then another shot Saturday and through the weekend. ECMWF
bring precip into the area late Friday and continues through the
weekend. GEM keeps us dry through 12z Saturday, but does match up
well to the GFS at that time. Went ahead and kept some small PoPs
in across much of the PAH forecast area Thursday night for some
light snow. By Saturday, when models seems to be lining up, went
with slight chance pops for Saturday for most of the PAH fa, with
increasing chances Saturday night into Sunday. Fortunately, it
looks like temperatures will be warm enough that it will just be
rain through the weekend. High by Sunday will only be a few degrees
below normal.
&&
.AVIATION...
Issued at 1105 PM CST SUN NOV 16 2014
All terminals should have changed over to snow by press time, as
the 32 line likewise makes its passage soon thereafter. IFR cigs
and vsbys accompany bands of moderate snow, while low end MVFR
cigs and vsbys prevail through the course of the night. The system
lifts out early, with improvement to VFR conditions anticipated
during the daylight hours, although cigs may maintain in the
northeast (KEVV/KOWB). Winds will stiffen and become gusty during
the pm hours.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WARNING until 6 AM CST Monday FOR ILZ087-089>094.
WINTER WEATHER ADVISORY until 6 AM CST Monday FOR ILZ075>078-
080>086-088.
MO...WINTER STORM WARNING until 6 AM CST Monday FOR MOZ110>112-114.
WINTER WEATHER ADVISORY until 6 AM CST Monday FOR MOZ076-086-087-
100-107>109.
IN...WINTER STORM WARNING until 6 AM CST Monday FOR INZ085>088.
WINTER WEATHER ADVISORY until 6 AM CST Monday FOR INZ081-082.
KY...WINTER STORM WARNING until 6 AM CST Monday FOR KYZ003>005-007-
010-014-015-018-019.
WINTER WEATHER ADVISORY until 6 AM CST Monday FOR KYZ001-002-006-
008-009-011>013-016-017-020>022.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1151 PM EST Sun Nov 16 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 1110 PM EST Nov 16 2014
Will be issuing an update to the Winter headline product soon, just
to freshen up the wording, not change any of the main points. Have
a pretty solid band of snow headed towards our northern forecast
area with more mixy precip still occurring on the south side of the
band. KOWB still is reporting rain even at 33 degrees, and KSDF has
been fluctuating between -RA, -RASN, and -RAPL, indicative of that
warm layer aloft, which should finally start pushing steadily south
a few hours after Midnight.
With the approach of the shortwave over Oklahoma still expecting an
increase in radar coverage overnight, which should hit most of the
advisory area. The southern edge will continue to run low on totals
given the warm initial ground cover as well as the antecedent rains.
Issued at 840 PM EST Nov 16 2014
Had another ACARS soundings showing a thinner warm layer aloft, but
still enough to melt the ice and then allow for some re-freezing, as
we have been getting a few more sleet reports. Observations deeper
into the cold over southern Indiana are showing all snow. Latest
water vapor loop shows the area of enhanced lift associated with the
right rear quadrant of an upper jet to our north. A potent
shortwave, now over Oklahoma, will merge with a longer wave trough
dropping down over the Central Plains to enhance precip further
overnight.
The warm nose may briefly re-exert it`s influence northward over the
next few hours before the cold air smashes through here late
tonight. The timing mentioned in our web briefings still looks
reasonable as well as the totals. Will add in better chances for
sleet, but overall this package is not a big change.
Issued at 620 PM EST Nov 16 2014
Had some good ACARS soundings in an hour or two ago, and basically
matched these up with the latest RUC temps aloft. Have used this
model for the next few hours to generate the transition zone for
rain to rain/snow mix to all snow. These changes did not change the
overall snow totals significantly, so no need to change the
advisory/warning area at this point. Will continue to monitor
multiple sources and adjust the forecast as needed through the
evening hours.
.SHORT TERM (Now through Monday Night)...
Issued at 340 PM EST Sun Nov 16 2014
...Accumulating Snows Likely Tonight into Monday...
Overview
--------
The short term period will feature a broad trough across much of the
CONUS. A strong PV anomaly is currently getting ready to enter the
southern Plains and will quickly slide east toward the mid
Mississipi Valley toward dawn. Ahead of this feature, surface
cyclogenesis is already occurring over the lower Mississippi. This
system will quickly lift NE and deepen as it slides by to our east
on Monday. Moisture is already spreading north into the region, and
will continue into tonight ahead of these slowly phasing systems.
This deep moisture will interact with increasingly colder
temperature profiles and produce a period of wintery weather across
the Ohio Valley.
Model Preference
----------------
There has been a wide model discrepancy with respect to thermal
profiles below 700 mb leading up to this event, overall leading to
low confidence. We did get a trend toward some better agreement with
the 12z runs, so decided to blend mainly between the 12z NAM/GFS
temperature profiles. Do think the outcome of this event ultimately
hinges more on the lower mid levels than nearer the surface, however
did want to mention that surface temperatures are expected to hover
around or just above freezing until the heavier snow falls toward
dawn.
Sensible Weather and Impacts
----------------------------
Current radar does show the two separate storm systems nicely with
light rain over southern KY and mainly light snow overspreading
central IL/IN. We`ll watch through the evening hours as deeper
moisture slowly invades the area, however expect only light
precipitation and no real impacts initially. Southern Indiana could
see light accumulations as early as around sunset. Precipitation will
likely mix at times even across our north as temp profiles fluctuate
under varying degrees of saturation. Really not expecting the main
show to get going until we approach Midnight as system becomes more
organized, column becomes more saturated, and surface temps wet bulb
down toward more wintery precip conducive numbers.
A frontogenetically forced band of snow will then ride SW to NE
across our Warning area, pivoting to a more SSW to NNE orientation
through the night as the right entrance region of an upper level jet
slides overhead. This pivoting should actually enhance the
frontogenesis as well as keep the warm nose near the Ohio River.
Thereafter, the approaching PV anomaly begins to rapidly push the
system east with cold air crashing in in the low to mid levels. The
surface low will strengthen as it slides just to our east, providing
more deep moisture to interact with the cold air.
Since the warm layer aloft is going to drive this event, will
characterize how the overnight progresses by describing its
evolution through several geographic areas.
Southern Indiana (Winter Storm Warning 3-5" of Snow)
----------------------------------------------------
This area is expected to stay below freezing through the thermal
column, so all snow is expected other than a brief mix at onset.
This is expected to yield 3-5 inches by Monday morning, with the
heaviest snow falling between Midnight and 7 AM EST. Impacts to
roads and travel are expected.
Right Along the Ohio River (Winter Weather Advisory 2-3" Snow)
--------------------------------------------------------------
This area is the northern portion of the battleground between the
warm nose aloft. Expect to see mainly snow, however a few brief
periods of wintery mix including some sleet should cut down on
totals a bit. Expect all snow around and after Midnight EST.
Just South of the Ohio River (Winter Weather Advisory 1-3" Snow and
a mix)
-------------------------------------------------------------------
This area will be more see more of the warm air aloft for a longer
time and should cut down on snow totals. Could also see more
bouts of sleet with no impact. The city of Louisville will be right
underneath this battleground, so bust potential is high in this
transition zone. Much will depend on how quick the changeover
occurs. Expect change over between 1 and 4 AM EST.
Bluegrass Region North of I-64 (Winter Weather Advisory 2-4" Snow)
------------------------------------------------------------------
Mostly rain before 4 AM EST. An enhanced area of snow after 4 AM
EST, where deeper moisture mentioned above will be present as two
storm systems phase.
South Central Kentucky (Impact Based Winter Weather Advisory 1" or
less and a brief mix)
-----------------------------------------------------------------
Transition time and the amount of deep moisture left are in question
in this area, as well as rainfall`s effect on ability to accumulate.
Nevertheless, a quick shot of snow around the morning commute, and
the first snow of the year is enough to warrant the advisory.
.LONG TERM (Tuesday through Sunday)...
Issued at 335 PM EST Sun Nov 16 2014
Forecast thoughts in the long term period have not changed much for
this forecast issuance as most of the forecasting focus was on the
Winter Storm Warning/Advisories in the short term period. See the
following excerpts from the previous discussion with a few added
thoughts below.
Deep upper troffing digging from eastern Canada into the United
States, with occasional small reinforcing shots moving through the
flow, will keep us cold for much of the work week, with any
appreciable moderation in temperatures holding off until the weekend
and into next week. Most moisture associated with the upper trof
will stay bottled up to our north, so though it will be cold, it
will also be mostly on the drier side (not necessarily *completely*
dry), with some moisture return possible next weekend.
The models are a mess in the long term, especially Thursday through
Sunday. Models are having difficulty with various shortwaves diving
south across the Plains in an a broad digging upper level trough.
These shortwaves will eventually bring us precip during the latter
half of the week but when, how much, and what type all remain in
question.
The main story Tuesday through Wednesday will be the cold. Tuesday
night we will drop well into the teens. Depending on the location
and depth of any snowpack from tonight`s snowfall, a reading or two
in the single digits may not be out of the question in sheltered
areas from southeast Indiana into the northern Blue Grass. High
temperatures on Tuesday will only be in the lower and middle 20s,
which is about 30 degrees colder than normal!
Wednesday we may be able to moderate up to around 40 in southwest
low level flow between high pressure over Dixie and a cold front
crossing the Great Lakes, but that will be offset by winds gusting
to 25 mph and afternoon wind chills mostly in the 20s.
As mentioned earlier, Thursday through Sunday are tough to figure
out right now. Will lean toward the drier side of the forecast
envelope and keep PoPs small for now. Will bring MaxT`s well up into
the 40s by Saturday with the anticipated pattern change.
&&
.AVIATION (06Z TAF Update)...
Updated at 1150 PM EST Sun Nov 16 2014
Winter conditions are on their way for the sites tonight. Have had
some sleet mixed in with rain at SDF, and this threat will push
east. Cigs have dropped to LIFR or worse and we should stay that way
for most if not all the overnight period. Expect a transition over
to all snow, first between now and roughly 07Z at KSDF and later at
the other two sites. Vsby will be worse once it goes over to all
snow, but have LIFR conditions persisting through mid morning, when
snow will start to exit off to the east and cigs will rise slowly.
Cannot rule out additional snow showers through the afternoon and
evening, as soundings don`t show much moisture, but that moisture is
in the ice crystal growth zone and there is some instability as
well. Winds will pick up from the west through the day tomorrow as
the cold air behind this system rushes in.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WINTER STORM WARNING until Noon EST /11 AM CST/ Monday FOR
KYZ023-032.
WINTER WEATHER ADVISORY from 3 AM EST /2 AM CST/ to Noon EST /11
AM CST/ Monday FOR KYZ027-036-037-039>043-045>049-053>057-
061>065-070>072.
WINTER WEATHER ADVISORY until Noon EST /11 AM CST/ Monday FOR
KYZ024>026-028>031-033>035-038.
IN...WINTER STORM WARNING until Noon EST /11 AM CST/ Monday FOR
INZ076>079-083-084-089>092.
&&
$$
Update.........RJS
Short Term.....BJS
Long Term......AMS
Aviation.......RJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1112 PM EST Sun Nov 16 2014
...Forecast Update...
Issued at 1110 PM EST Nov 16 2014
Will be issuing an update to the Winter headline product soon, just
to freshen up the wording, not change any of the main points. Have
a pretty solid band of snow headed towards our northern forecast
area with more mixy precip still occurring on the south side of the
band. KOWB still is reporting rain even at 33 degrees, and KSDF has
been fluctuating between -RA, -RASN, and -RAPL, indicative of that
warm layer aloft, which should finally start pushing steadily south
a few hours after Midnight.
With the approach of the shortwave over Oklahoma still expecting an
increase in radar coverage overnight, which should hit most of the
advisory area. The southern edge will continue to run low on totals
given the warm initial ground cover as well as the antecedent rains.
Issued at 840 PM EST Nov 16 2014
Had another ACARS soundings showing a thinner warm layer aloft, but
still enough to melt the ice and then allow for some re-freezing, as
we have been getting a few more sleet reports. Observations deeper
into the cold over southern Indiana are showing all snow. Latest
water vapor loop shows the area of enhanced lift associated with the
right rear quadrant of an upper jet to our north. A potent
shortwave, now over Oklahoma, will merge with a longer wave trough
dropping down over the Central Plains to enhance precip further
overnight.
The warm nose may briefly re-exert it`s influence northward over the
next few hours before the cold air smashes through here late
tonight. The timing mentioned in our web briefings still looks
reasonable as well as the totals. Will add in better chances for
sleet, but overall this package is not a big change.
Issued at 620 PM EST Nov 16 2014
Had some good ACARS soundings in an hour or two ago, and basically
matched these up with the latest RUC temps aloft. Have used this
model for the next few hours to generate the transition zone for
rain to rain/snow mix to all snow. These changes did not change the
overall snow totals significantly, so no need to change the
advisory/warning area at this point. Will continue to monitor
multiple sources and adjust the forecast as needed through the
evening hours.
.SHORT TERM (Now through Monday Night)...
Issued at 340 PM EST Sun Nov 16 2014
...Accumulating Snows Likely Tonight into Monday...
Overview
--------
The short term period will feature a broad trough across much of the
CONUS. A strong PV anomaly is currently getting ready to enter the
southern Plains and will quickly slide east toward the mid
Mississipi Valley toward dawn. Ahead of this feature, surface
cyclogenesis is already occurring over the lower Mississippi. This
system will quickly lift NE and deepen as it slides by to our east
on Monday. Moisture is already spreading north into the region, and
will continue into tonight ahead of these slowly phasing systems.
This deep moisture will interact with increasingly colder
temperature profiles and produce a period of wintery weather across
the Ohio Valley.
Model Preference
----------------
There has been a wide model discrepancy with respect to thermal
profiles below 700 mb leading up to this event, overall leading to
low confidence. We did get a trend toward some better agreement with
the 12z runs, so decided to blend mainly between the 12z NAM/GFS
temperature profiles. Do think the outcome of this event ultimately
hinges more on the lower mid levels than nearer the surface, however
did want to mention that surface temperatures are expected to hover
around or just above freezing until the heavier snow falls toward
dawn.
Sensible Weather and Impacts
----------------------------
Current radar does show the two separate storm systems nicely with
light rain over southern KY and mainly light snow overspreading
central IL/IN. We`ll watch through the evening hours as deeper
moisture slowly invades the area, however expect only light
precipitation and no real impacts initially. Southern Indiana could
see light accumulations as early as around sunset. Precipitation will
likely mix at times even across our north as temp profiles fluctuate
under varying degrees of saturation. Really not expecting the main
show to get going until we approach Midnight as system becomes more
organized, column becomes more saturated, and surface temps wet bulb
down toward more wintery precip conducive numbers.
A frontogenetically forced band of snow will then ride SW to NE
across our Warning area, pivoting to a more SSW to NNE orientation
through the night as the right entrance region of an upper level jet
slides overhead. This pivoting should actually enhance the
frontogenesis as well as keep the warm nose near the Ohio River.
Thereafter, the approaching PV anomaly begins to rapidly push the
system east with cold air crashing in in the low to mid levels. The
surface low will strengthen as it slides just to our east, providing
more deep moisture to interact with the cold air.
Since the warm layer aloft is going to drive this event, will
characterize how the overnight progresses by describing its
evolution through several geographic areas.
Southern Indiana (Winter Storm Warning 3-5" of Snow)
----------------------------------------------------
This area is expected to stay below freezing through the thermal
column, so all snow is expected other than a brief mix at onset.
This is expected to yield 3-5 inches by Monday morning, with the
heaviest snow falling between Midnight and 7 AM EST. Impacts to
roads and travel are expected.
Right Along the Ohio River (Winter Weather Advisory 2-3" Snow)
--------------------------------------------------------------
This area is the northern portion of the battleground between the
warm nose aloft. Expect to see mainly snow, however a few brief
periods of wintery mix including some sleet should cut down on
totals a bit. Expect all snow around and after Midnight EST.
Just South of the Ohio River (Winter Weather Advisory 1-3" Snow and
a mix)
-------------------------------------------------------------------
This area will be more see more of the warm air aloft for a longer
time and should cut down on snow totals. Could also see more
bouts of sleet with no impact. The city of Louisville will be right
underneath this battleground, so bust potential is high in this
transition zone. Much will depend on how quick the changeover
occurs. Expect change over between 1 and 4 AM EST.
Bluegrass Region North of I-64 (Winter Weather Advisory 2-4" Snow)
------------------------------------------------------------------
Mostly rain before 4 AM EST. An enhanced area of snow after 4 AM
EST, where deeper moisture mentioned above will be present as two
storm systems phase.
South Central Kentucky (Impact Based Winter Weather Advisory 1" or
less and a brief mix)
-----------------------------------------------------------------
Transition time and the amount of deep moisture left are in question
in this area, as well as rainfall`s effect on ability to accumulate.
Nevertheless, a quick shot of snow around the morning commute, and
the first snow of the year is enough to warrant the advisory.
.LONG TERM (Tuesday through Sunday)...
Issued at 335 PM EST Sun Nov 16 2014
Forecast thoughts in the long term period have not changed much for
this forecast issuance as most of the forecasting focus was on the
Winter Storm Warning/Advisories in the short term period. See the
following excerpts from the previous discussion with a few added
thoughts below.
Deep upper troffing digging from eastern Canada into the United
States, with occasional small reinforcing shots moving through the
flow, will keep us cold for much of the work week, with any
appreciable moderation in temperatures holding off until the weekend
and into next week. Most moisture associated with the upper trof
will stay bottled up to our north, so though it will be cold, it
will also be mostly on the drier side (not necessarily *completely*
dry), with some moisture return possible next weekend.
The models are a mess in the long term, especially Thursday through
Sunday. Models are having difficulty with various shortwaves diving
south across the Plains in an a broad digging upper level trough.
These shortwaves will eventually bring us precip during the latter
half of the week but when, how much, and what type all remain in
question.
The main story Tuesday through Wednesday will be the cold. Tuesday
night we will drop well into the teens. Depending on the location
and depth of any snowpack from tonight`s snowfall, a reading or two
in the single digits may not be out of the question in sheltered
areas from southeast Indiana into the northern Blue Grass. High
temperatures on Tuesday will only be in the lower and middle 20s,
which is about 30 degrees colder than normal!
Wednesday we may be able to moderate up to around 40 in southwest
low level flow between high pressure over Dixie and a cold front
crossing the Great Lakes, but that will be offset by winds gusting
to 25 mph and afternoon wind chills mostly in the 20s.
As mentioned earlier, Thursday through Sunday are tough to figure
out right now. Will lean toward the drier side of the forecast
envelope and keep PoPs small for now. Will bring MaxT`s well up into
the 40s by Saturday with the anticipated pattern change.
&&
.AVIATION (00Z TAF Update)...
Updated at 620 PM EST Sun Nov 16 2014
Winter conditions are on their way for the sites tonight. Cigs will
drop to LIFR or worse for most if not all the overnight period. Rain
ongoing now will transition over to snow, first between 04 and 07Z
at KSDF and later at the other two sites. Vsby will be worse once it
goes over to all snow, but have LIFR conditions persiste through mid
morning, when snow will start to exit off to the east and cigs will
rise slowly. Cannot rule out additional snow showers through the
afternoon and evening, as soundings don`t show much moisture, but
that moisture is in the ice crystal growth zone and there is some
instability as well. Winds will pick up from the west and northwest
through the day tomorrow as the cold air behind this system rushes
in.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WINTER STORM WARNING until Noon EST /11 AM CST/ Monday FOR
KYZ023-032.
WINTER WEATHER ADVISORY from 3 AM EST /2 AM CST/ to Noon EST /11
AM CST/ Monday FOR KYZ027-036-037-039>043-045>049-053>057-
061>065-070>072.
WINTER WEATHER ADVISORY until Noon EST /11 AM CST/ Monday FOR
KYZ024>026-028>031-033>035-038.
IN...WINTER STORM WARNING until Noon EST /11 AM CST/ Monday FOR
INZ076>079-083-084-089>092.
&&
$$
Update.........RJS
Short Term.....BJS
Long Term......AMS
Aviation.......RJS
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1137 PM CST SUN NOV 16 2014
.AVIATION...
SECOND FRONT EXTENDS FROM RAPIDES SOUTH TO CAMERON PARISH THEN OUT
INTO THE GULF. CLOUDS EXTEND BACK INTO CENTRAL TEXAS AS NW WINDS
HAVE PICKED UP OVER THE REGION. LOW CLOUDS LOOK TO EXIT DRG THE
OVERNIGHT HOURS WHILE MID DECK HANGS ON THRU SUNRISE BEFORE
BEGINNING TO BREAK. LFT AND ARA WILL SEE MORE SHWRS IN THE NEXT
SEVERAL HOURS BEFORE THEY EXIT INTO EASTERN LOUISIANA.
&&
.PREV DISCUSSION... /ISSUED 1021 PM CST SUN NOV 16 2014/
UPDATE...ZONES AND GRIDS UPDATED TO REFLECT WIND ADVISORY.
BEAUMONT IS JUST NOW APPROACHING WIND ADVISORY CRITERIA. THE
SECONDARY FRONTAL BAND EXTENDS FROM BEAUMONT TO DERIDDER AND ALEXANDRIA.
THIS BAND IS MOVING SOUTHEAST AT AROUND 25 MPH. GUSTS TO 35 MPH
APPEAR POSSIBLE.
SWEENEY
PREV DISCUSSION... /ISSUED 937 PM CST SUN NOV 16 2014/
UPDATE...MADE MINOR ADJUSTMENT TO THE SURFACE WINDS WITH
SLIGHTLY STRONGER WINDS OVERNIGHT WITH THE REINFORCING COLD FRONT
CURRENTLY MOVING THROUGH SOUTHEAST TEXAS AND CENTRAL
LOUISIANA. BLENDED IN LATEST RUC TEMP DATA AND DEW POINT TRENDS
AS WELL AS ACCOUNTING FOR A SLOWER MOVEMENT OF THE COLD FRONT
THROUGH ACADIANA TO ADJUST OVERNIGHT TEMPERATURES. STILL QUITE A
DROP EXPECTED BUT NOW EXPECTING MID 40S FOR SW LA AND UPPER 40S
FOR S CEN LA BY SUNRISE DUE LARGELY TO THE INCREASING WINDS. THESE
CHANGES WILL BE REFLECTED IN ANOTHER ZONE UPDATE OUT SHORTLY.
SWEENEY
PREV DISCUSSION... /ISSUED 832 PM CST SUN NOV 16 2014/
UPDATE...WENT AHEAD AND CANCELLED THE TOR WATCH A COUPLE OF
HOURS EARLY. WAS IN THE PROCESS OF TRIMMING BACK HOWEVER THE WINDS
AND LIFT BOTH APPEAR TO HAVE WEAKEN AROUND THE FRONTAL BAND. ZONE
UPDATE TO FOLLOW.
SWEENEY
PREV DISCUSSION... /ISSUED 553 PM CST SUN NOV 16 2014/
AVIATION...
STRONG THUNDERSTORMS ARE RUMBLING THRU SOUTH CENTRAL LA AND WILL
BE AN OPERATIONAL ISSUE FOR ARA AND LFT OVER THE NEXT HOUR OR SO.
OTHERWISE LOW CEILINGS WITH PERIODS OF RAINS AND FOG WILL KEEP
VSBY DOWN AT TIMES. CONDITIONS WILL IMPROVE AS A SECOND FRONT
MOVES THROUGH LATE TONIGHT WITH WINDS PICKING UP.
PREV DISCUSSION... /ISSUED 344 PM CST SUN NOV 16 2014/
DISCUSSION...
BUSY WEATHER SITUATION ACROSS THE FORECAST AREA...WITH CONDITIONS
VARYING FROM SPRING TO WINTER WITH SOME 25F DEGREE AIR TEMPERATURE
BETWEEN THE NORTHWEST PORTION OF THE FORECAST AREA WITH THE
SOUTHEAST. OLD FRONTAL BOUNDARY IS BISECTING THE FORECAST AREA
WITH A SURFACE LOW/FRONTAL WAVE LOCATED AS OF 16/21Z BETWEEN
JENNINGS AND LAFAYETTE. WARM SECTOR ON THE EAST SIDE OF THE LOW
EXTENDS FROM EASTERN ST. LANDRY PARISH NEAR THE ATCHAFALAYA BASIN
TO INTO THE GULF WATERS AROUND THE CAMERON/VERMILION PARISH
BORDER. SOME STRONG LOW LEVEL INFLOW WITH A VERY WARM AND MOIST
ENVIRONMENT IS LEADING TO THE DEVELOPMENT OF SHOWERS WITH SOME
EMBEDDED STRONG THUNDERSTORMS IN THE WARM SECTOR. THERE IS A
CHANCE OF SOME ROTATING CELLS BECOMING SURFACE BASED IN THE WARM
SECTOR...AND THEREFORE...SPC HAS ISSUED A TORNADO WATCH FOR SOUTH
CENTRAL LOUISIANA THROUGH 10 PM...ALTHOUGH THE THREAT SHOULD
DIMINISH FOR PORTIONS OF THE AREA BEFORE THEN...AS THE LOW
CONTINUES TO MOVE TO THE NORTHEAST AND LOSS OF DAYTIME HEATING
DECREASES THE LOW LEVEL INSTABILITY.
ANOTHER STRONG COLD FRONT WITH ARCTIC ORIGINS IS CURRENTLY MOVING
SOUTHEAST ACROSS NORTHEAST TEXAS AND NORTHWEST LOUISIANA. THIS
SYSTEM WILL MOVE INTO THE FORECAST AREA THIS EVENING AND INTO THE
COASTAL WATERS DURING THE OVERNIGHT. SHOWERS WILL DECREASE BEHIND
THIS FRONT AS MUCH DRIER AIR BEGINS TO MOVE IN...ALONG WITH
BLUSTERY CONDITIONS.
COLD AIR ADVECTION WILL CONTINUE ON MONDAY...AS THE STRONG HIGH
PRESSURE SYSTEM BUILDS DOWN FROM THE NORTH. CLEAR SKIES ARE
EXPECTED ON MONDAY NIGHT INTO TUESDAY MORNING...WITH A DECREASE IN
WINDS EXPECTED. THEREFORE...A VERY COLD NIGHT IS EXPECTED WITH A
FREEZE FOR A MAJORITY OF THE FORECAST AREA...AND HARD FREEZE
CONDITIONS GETTING DOWN CLOSE TO I-10.
CONDITIONS WILL BEGIN TO MODERATE BY MID-WEEK AS THE HIGH MOVES
OFF TO THE EAST...AND RETURN FLOW OFF THE GULF COMMENCES. ENOUGH
MOISTURE BUILD-UP BY THURSDAY INTO THE WEEKEND...TO INCLUDE A
CHANCE FOR SHOWERS AND STORMS AS A SERIES OF UPPER LEVEL
DISTURBANCES MOVE ACROSS.
RUA
MARINE...
A SURFACE LOW/FRONTAL WAVE WILL MOVE ACROSS SOUTH CENTRAL
LOUISIANA THIS EVENING...THEN SOUTHEAST LOUISIANA TONIGHT.
MODERATE SOUTHERLY WINDS AND INSTABILITY WILL BRING ABOUT SHOWERS
AND STORMS...ESPECIALLY EAST OF CAMERON DURING THE EVENING HOURS.
SOME OF THESE STORMS WILL PRODUCE FREQUENT LIGHTNING...STRONG
WINDS...AND EVEN AN ISOLATED WATER SPOUT CAN NOT BE RULED OUT.
A STRONG COLD FRONT...WILL THEN MOVE ACROSS THE COASTAL WATERS
LATER TONIGHT...REACHING THE WESTERN PORTIONS OF THE COASTAL
WATERS DURING THE LATE EVENING HOURS...AND THEN ACROSS THE
REMAINDER OF THE COASTAL WATERS AFTER MIDNIGHT. AIR FROM THE POLAR
REGION WILL BE BEHIND THIS FRONT. THE DEVELOPING PRESSURE GRADIENT
FROM THE STRONG HIGH PRESSURE SYSTEM...AND STRONG COLD AIR
ADVECTION...WILL PROVIDE TURBULENT AIR MIXING...ALLOWING SOME
STRONG WIND GUSTS TO REACH THE SURFACE...ESPECIALLY OVER THE OUTER
WATERS. THEREFORE...SMALL CRAFT ADVISORY CONDITIONS WILL OVERTAKE
THE COASTAL WATERS TONIGHT...WITH A GALE WARNING FOR FREQUENT WIND
GUSTS OVER 40 KNOTS...BEYOND 20 NM. THE NORTH WIND WILL ALSO PUSH
WATER OUT OF THE CHANNELS AND BAYS AND AWAY FROM THE COAST.
THEREFORE...A LOW WATER ADVISORY WILL ALSO BE IN EFFECT FOR THE
COASTAL LAKES AND BAYS FROM ROUGHLY MIDNIGHT TONIGHT THROUGH NOON MONDAY.
THE STRONG NORTHERLY WINDS WILL BEGIN TO DECREASE BY TUESDAY AS
THE COLD AIR ADVECTION BEGINS TO WANE AND THE HIGH PRESSURE SYSTEM
SETTLES OVER THE REGION.
RUA
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 44 50 27 49 32 / 80 10 0 0 0
KBPT 41 51 29 50 37 / 70 10 0 0 0
KAEX 38 47 24 46 29 / 80 10 0 0 0
KLFT 48 49 27 47 31 / 90 10 0 0 0
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...WIND ADVISORY UNTIL 6 AM CST MONDAY FOR THE FOLLOWING ZONES:
ACADIA...ALLEN...BEAUREGARD...CALCASIEU...EAST CAMERON...
IBERIA...JEFFERSON DAVIS...LAFAYETTE...ST. MARY...
VERMILION...WEST CAMERON.
TX...WIND ADVISORY UNTIL 6 AM CST MONDAY FOR THE FOLLOWING ZONES:
JEFFERSON...ORANGE.
GM...SMALL CRAFT ADVISORY FROM NOON MONDAY TO NOON CST TUESDAY FOR
THE FOLLOWING ZONES: WATERS FROM INTRACOASTAL CITY TO
CAMERON LA FROM 20 TO 60 NM...WATERS FROM CAMERON LA TO
HIGH ISLAND TX FROM 20 TO 60 NM...WATERS FROM LOWER
ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA FROM 20 TO 60 NM.
GALE WARNING UNTIL NOON CST MONDAY FOR THE FOLLOWING ZONES:
WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA
FROM 20 TO 60 NM.
GALE WARNING UNTIL NOON CST MONDAY FOR THE FOLLOWING ZONES:
WATERS FROM INTRACOASTAL CITY TO CAMERON LA FROM 20 TO 60
NM...WATERS FROM CAMERON LA TO HIGH ISLAND TX FROM 20 TO 60
NM.
LOW WATER ADVISORY UNTIL NOON CST MONDAY FOR THE FOLLOWING
ZONES: CALCASIEU LAKE...SABINE LAKE...VERMILION BAY.
SMALL CRAFT ADVISORY UNTIL NOON CST MONDAY FOR THE FOLLOWING
ZONES: CALCASIEU LAKE...SABINE LAKE...VERMILION BAY.
SMALL CRAFT ADVISORY UNTIL NOON CST TUESDAY FOR THE FOLLOWING
ZONES: COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO
INTRACOASTAL CITY LA OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL NOON CST TUESDAY FOR THE FOLLOWING
ZONES: COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT
20 NM...COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA
OUT 20 NM.
&&
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSLAKECHARLES
WWW.TWITTER.COM/NWSLAKECHARLES
WWW.YOUTUBE.COM/NWSLAKECHARLES
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1021 PM CST SUN NOV 16 2014
.UPDATE...ZONES AND GRIDS UPDATED TO REFLECT WIND ADVISORY.
BEAUMONT IS JUST NOW APPROACHING WIND ADVISORY CRITERIA. THE
SECONDARY FRONTAL BAND EXTENDS FROM BEAUMONT TO DERIDDER AND ALEXANDRIA.
THIS BAND IS MOVING SOUTHEAST AT AROUND 25 MPH. GUSTS TO 35 MPH
APPEAR POSSIBLE.
SWEENEY
&&
.PREV DISCUSSION... /ISSUED 937 PM CST SUN NOV 16 2014/
UPDATE...MADE MINOR ADJUSTMENT TO THE SURFACE WINDS WITH
SLIGHTLY STRONGER WINDS OVERNIGHT WITH THE REINFORCING COLD FRONT
CURRENTLY MOVING THROUGH SOUTHEAST TEXAS AND CENTRAL
LOUISIANA. BLENDED IN LATEST RUC TEMP DATA AND DEW POINT TRENDS
AS WELL AS ACCOUNTING FOR A SLOWER MOVEMENT OF THE COLD FRONT
THROUGH ACADIANA TO ADJUST OVERNIGHT TEMPERATURES. STILL QUITE A
DROP EXPECTED BUT NOW EXPECTING MID 40S FOR SW LA AND UPPER 40S
FOR S CEN LA BY SUNRISE DUE LARGELY TO THE INCREASING WINDS. THESE
CHANGES WILL BE REFLECTED IN ANOTHER ZONE UPDATE OUT SHORLTY.
SWEENEY
PREV DISCUSSION... /ISSUED 832 PM CST SUN NOV 16 2014/
UPDATE...WENT AHEAD AND CANCELLED THE TOR WATCH A COUPLE OF
HOURS EARLY. WAS IN THE PROCESS OF TRIMMING BACK HOWEVER THE WINDS
AND LIFT BOTH APPEAR TO HAVE WEAKEND AROUND THE FRONTAL BAND. ZONE
UPDATE TO FOLLOW.
SWEENEY
PREV DISCUSSION... /ISSUED 553 PM CST SUN NOV 16 2014/
AVIATION...
STRONG THUNDERSTORMS ARE RUMBLING THRU SOUTH CENTRAL LA AND WILL
BE AN OPERATIONAL ISSUE FOR ARA AND LFT OVER THE NEXT HOUR OR SO.
OTHERWISE LOW CEILINGS WITH PERIODS OF RAINS AND FOG WILL KEEP
VSBY DOWN AT TIMES. CONDITIONS WILL IMPROVE AS A SECOND FRONT
MOVES THROUGH LATE TONIGHT WITH WINDS PICKING UP.
PREV DISCUSSION... /ISSUED 344 PM CST SUN NOV 16 2014/
DISCUSSION...
BUSY WEATHER SITUATION ACROSS THE FORECAST AREA...WITH CONDITIONS
VARYING FROM SPRING TO WINTER WITH SOME 25F DEGREE AIR TEMPERATURE
BETWEEN THE NORTHWEST PORTION OF THE FORECAST AREA WITH THE
SOUTHEAST. OLD FRONTAL BOUNDARY IS BISECTING THE FORECAST AREA
WITH A SURFACE LOW/FRONTAL WAVE LOCATED AS OF 16/21Z BETWEEN
JENNINGS AND LAFAYETTE. WARM SECTOR ON THE EAST SIDE OF THE LOW
EXTENDS FROM EASTERN ST. LANDRY PARISH NEAR THE ATCHAFALAYA BASIN
TO INTO THE GULF WATERS AROUND THE CAMERON/VERMILION PARISH
BORDER. SOME STRONG LOW LEVEL INFLOW WITH A VERY WARM AND MOIST
ENVIRONMENT IS LEADING TO THE DEVELOPMENT OF SHOWERS WITH SOME
EMBEDDED STRONG THUNDERSTORMS IN THE WARM SECTOR. THERE IS A
CHANCE OF SOME ROTATING CELLS BECOMING SURFACE BASED IN THE WARM
SECTOR...AND THEREFORE...SPC HAS ISSUED A TORNADO WATCH FOR SOUTH
CENTRAL LOUISIANA THROUGH 10 PM...ALTHOUGH THE THREAT SHOULD
DIMINISH FOR PORTIONS OF THE AREA BEFORE THEN...AS THE LOW
CONTINUES TO MOVE TO THE NORTHEAST AND LOSS OF DAYTIME HEATING
DECREASES THE LOW LEVEL INSTABILITY.
ANOTHER STRONG COLD FRONT WITH ARCTIC ORIGINS IS CURRENTLY MOVING
SOUTHEAST ACROSS NORTHEAST TEXAS AND NORTHWEST LOUISIANA. THIS
SYSTEM WILL MOVE INTO THE FORECAST AREA THIS EVENING AND INTO THE
COASTAL WATERS DURING THE OVERNIGHT. SHOWERS WILL DECREASE BEHIND
THIS FRONT AS MUCH DRIER AIR BEGINS TO MOVE IN...ALONG WITH
BLUSTERY CONDITIONS.
COLD AIR ADVECTION WILL CONTINUE ON MONDAY...AS THE STRONG HIGH
PRESSURE SYSTEM BUILDS DOWN FROM THE NORTH. CLEAR SKIES ARE
EXPECTED ON MONDAY NIGHT INTO TUESDAY MORNING...WITH A DECREASE IN
WINDS EXPECTED. THEREFORE...A VERY COLD NIGHT IS EXPECTED WITH A
FREEZE FOR A MAJORITY OF THE FORECAST AREA...AND HARD FREEZE
CONDITIONS GETTING DOWN CLOSE TO I-10.
CONDITIONS WILL BEGIN TO MODERATE BY MID-WEEK AS THE HIGH MOVES
OFF TO THE EAST...AND RETURN FLOW OFF THE GULF COMMENCES. ENOUGH
MOISTURE BUILD-UP BY THURSDAY INTO THE WEEKEND...TO INCLUDE A
CHANCE FOR SHOWERS AND STORMS AS A SERIES OF UPPER LEVEL
DISTURBANCES MOVE ACROSS.
RUA
MARINE...
A SURFACE LOW/FRONTAL WAVE WILL MOVE ACROSS SOUTH CENTRAL
LOUISIANA THIS EVENING...THEN SOUTHEAST LOUISIANA TONIGHT.
MODERATE SOUTHERLY WINDS AND INSTABILITY WILL BRING ABOUT SHOWERS
AND STORMS...ESPECIALLY EAST OF CAMERON DURING THE EVENING HOURS.
SOME OF THESE STORMS WILL PRODUCE FREQUENT LIGHTNING...STRONG
WINDS...AND EVEN AN ISOLATED WATER SPOUT CAN NOT BE RULED OUT.
A STRONG COLD FRONT...WILL THEN MOVE ACROSS THE COASTAL WATERS
LATER TONIGHT...REACHING THE WESTERN PORTIONS OF THE COASTAL
WATERS DURING THE LATE EVENING HOURS...AND THEN ACROSS THE
REMAINDER OF THE COASTAL WATERS AFTER MIDNIGHT. AIR FROM THE POLAR
REGION WILL BE BEHIND THIS FRONT. THE DEVELOPING PRESSURE GRADIENT
FROM THE STRONG HIGH PRESSURE SYSTEM...AND STRONG COLD AIR
ADVECTION...WILL PROVIDE TURBULENT AIR MIXING...ALLOWING SOME
STRONG WIND GUSTS TO REACH THE SURFACE...ESPECIALLY OVER THE OUTER
WATERS. THEREFORE...SMALL CRAFT ADVISORY CONDITIONS WILL OVERTAKE
THE COASTAL WATERS TONIGHT...WITH A GALE WARNING FOR FREQUENT WIND
GUSTS OVER 40 KNOTS...BEYOND 20 NM. THE NORTH WIND WILL ALSO PUSH
WATER OUT OF THE CHANNELS AND BAYS AND AWAY FROM THE COAST.
THEREFORE...A LOW WATER ADVISORY WILL ALSO BE IN EFFECT FOR THE
COASTAL LAKES AND BAYS FROM ROUGHLY MIDNIGHT TONIGHT THROUGH NOON MONDAY.
THE STRONG NORTHERLY WINDS WILL BEGIN TO DECREASE BY TUESDAY AS
THE COLD AIR ADVECTION BEGINS TO WANE AND THE HIGH PRESSURE SYSTEM
SETTLES OVER THE REGION.
RUA
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 44 50 27 49 32 / 80 10 0 0 0
KBPT 41 51 29 50 37 / 70 10 0 0 0
KAEX 38 47 24 46 29 / 80 10 0 0 0
KLFT 48 49 27 47 31 / 90 10 0 0 0
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...WIND ADVISORY UNTIL 6 AM CST MONDAY FOR THE FOLLOWING ZONES:
ACADIA...ALLEN...BEAUREGARD...CALCASIEU...EAST CAMERON...
IBERIA...JEFFERSON DAVIS...LAFAYETTE...ST. MARY...
VERMILION...WEST CAMERON.
TX...WIND ADVISORY UNTIL 6 AM CST MONDAY FOR THE FOLLOWING ZONES:
JEFFERSON...ORANGE.
GM...SMALL CRAFT ADVISORY FROM NOON MONDAY TO NOON CST TUESDAY FOR
THE FOLLOWING ZONES: WATERS FROM INTRACOASTAL CITY TO
CAMERON LA FROM 20 TO 60 NM...WATERS FROM CAMERON LA TO
HIGH ISLAND TX FROM 20 TO 60 NM...WATERS FROM LOWER
ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA FROM 20 TO 60 NM.
GALE WARNING UNTIL NOON CST MONDAY FOR THE FOLLOWING ZONES:
WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA
FROM 20 TO 60 NM.
GALE WARNING UNTIL NOON CST MONDAY FOR THE FOLLOWING ZONES:
WATERS FROM INTRACOASTAL CITY TO CAMERON LA FROM 20 TO 60
NM...WATERS FROM CAMERON LA TO HIGH ISLAND TX FROM 20 TO 60
NM.
LOW WATER ADVISORY UNTIL NOON CST MONDAY FOR THE FOLLOWING
ZONES: CALCASIEU LAKE...SABINE LAKE...VERMILION BAY.
SMALL CRAFT ADVISORY UNTIL NOON CST MONDAY FOR THE FOLLOWING
ZONES: CALCASIEU LAKE...SABINE LAKE...VERMILION BAY.
SMALL CRAFT ADVISORY UNTIL NOON CST TUESDAY FOR THE FOLLOWING
ZONES: COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO
INTRACOASTAL CITY LA OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL NOON CST TUESDAY FOR THE FOLLOWING
ZONES: COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT
20 NM...COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA
OUT 20 NM.
&&
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSLAKECHARLES
WWW.TWITTER.COM/NWSLAKECHARLES
WWW.YOUTUBE.COM/NWSLAKECHARLES
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
414 AM EST MON NOV 17 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 411 AM EST MON NOV 17 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS INDICATE A DEEPENING
UPR TROF OVER CENTRAL NAMERICA WITH CLOSED H5 LO OVER ONTARIO JUST
NW OF LK SUP CAUSING 12HR H5 HGT FALLS UP TO 130M BTWN 16/12Z AND
17/00Z AT INL AND DRAWING H5 TEMPS CLOSE TO -40C S UNDER THE AXIS OF
LOWEST HGTS. BAND OF DPVA/DEEP LYR QVECTOR CNVGC/AXIS OF MID LVL
MSTR IN ADVANCE OF SHRTWV ROTATING ARND THE CLOSED LO IS CROSSING
UPR MI EARLY THIS MRNG...BUT DRYNESS OF AIRMASS SHOWN ON THE 00Z GRB
RAOB /PWAT 0.16 INCH IS 45 PCT OF NORMAL/ IS GREATLY LIMITING THE
COVERAGE/INTENSITY OF ACCOMPANYING LIGHT SN. THERE HAS BEEN SOME
LIGHT SN OVER THE FAR E NEAR NEWBERRY WITH A SW WIND OFF NRN LK
MI...BUT THE FLOW HAS NOT BACKED SUFFICIENTLY TO CAUSE THE HEAVIER
SN SHOWERS IN MACKINAC COUNTY TO IMPACT LUCE/SCHOOLCRAFT COUNTIES.
LOOKING TO THE W...THE 00Z H85/7 TEMPS WERE -17C/-27C AT INL /VS
-14C AND -16C AT GRB/. THE 00Z INL IS QUITE MOIST ALMOST UP TO H5
WITHIN A DEEP CYC FLOW. THERE IS A SHARP SFC WSHFT FM W TO NW ALONG
A SFC LO PRES TROF RUNNING THRU NRN MN INTO ADJACENT ONTARIO...WITH
SFC REPORTS SHOWING SOME MODERATE SN ALONG AND JUST BEHIND THIS
BNDRY.
MAIN FOCUS IN THE SHORT TERM WL BE ON LES AMOUNTS/GOING HEADLINES
ASSOCIATED WITH INCOMING COLD/MOIST AIRMASS. MADE NO CHANGES ATTM TO
HEADLINES ISSUED BY THE PREVIOUS SHIFT.
TODAY...AS CUTOFF H5 LO DEEPENS FURTHER AND SLIDES SLOWLY TO THE E
ACROSS UPR MI...SHARP CYC LLVL FLOW IS FCST TO SLOWLY ENVELOP THE
CWA W-E WITH A WSHFT FM WSW EARLY THIS MRNG TO NW BY LATE IN THE DAY
EXCEPT OVER THE SE CWA. THE SHARPER LLVL CNVGC WL ARRIVE OVER THE W
ARND 12Z AND RESULT IN INCRSG SN RATES DESPITE SOME DEEP LYR QVECTOR
DVGC IN THE WAKE OF THE SHRTWV ROTATING THRU THE UPR LKS EARLY THIS
MRNG. THE HIER RES MODELS HAVE CONSISTENTLY POINTED TO THE AREA ARND
ONTONAGON COUNTY AS THE FOCUS FOR THE SHARPEST CNVGC. GOING START
TIME OF 12Z FOR THE WARNINGS OVER THE W APPEARS TO BE ON TRACK.
SINCE THE RATHER LO UVV MAX IN THE ABSENCE OF DEEP LYR FORCING WL BE
CENTERED IN THE DGZ...EXPECT GOOD SN/WATER RATIOS IN EXCESS OF 20:1
DESPITE A DGZ DEPTH OF ONLY ABOUT 3K FT AND INCRSG WINDS THAT WOULD
TEND TO FRAGMENT THE SN FLAKES. WITH SOME INCRSG DEEP LYR QVECTOR
CNVGC/UVV OVER THE W HALF LATER IN THE DAY UNDER THE DEEPENING UPR
TROF AXIS...FCST SDNGS ALSO INDICATE INCRSG DEEP MSTR THRU THE DAY
PER THE 00Z INL RAOB WITH EQUILIBRIUM LVLS APRCHG 10K FT OVER THE BY
LATER IN THE DAY AS H85/7 TEMPS DIP TO -16C TO -17C/-27C. INCRSG NW
WINDS/DESTABILIZATION WL RESULT IN GUSTY SFC WINDS AND SOME BLSN AS
WELL. FARTHER TO THE E...THE LLVL FLOW IS FCST TO BE OUT OF THE W
MOST OF THE DAY...SO THE SN SHOWERS THERE SHOULD BE MAINLY CONFINED
TO THE LK SHORE UNTIL AT LEAST 21Z...WHEN THE FASTER HI RES CNDN
MODEL SHOWS THE ARRIVAL OF SHARPER CYC FLOW/ WSHFT TO THE NW. FCST
LES WARNINGS FOR ALGER/NRN SCHOOLCRAFT COUNTIES BEGINS AT 21Z...SO
WL NOT CHANGE THIS START TIME. THERE SHOULD BE NOTHING MORE THAN
FLURRIES/LIGHT SN SHOWERS OVER THE SCENTRAL WITH DOWNSLOPE FLOW.
TNGT...UPR TROF/AXIS OF DEEP LYR QVECTOR CNVGC AND MSTR/SFC LO PRES
TROF AND CYC WSHFT TO THE NW ARE PROGGED TO DRIFT SLOWLY E. THESE
TRENDS WL RESULT IN INCRSG POPS/SN RATES IN THE NW SN BELTS MAINLY E
OF MARQUETTE. THE 00Z NAM AND ESPECIALLY THE HI RES CNDN MODEL HINT
LK NIPIGON MOISTENING WL GREATLY ENHANCE SN RATES OVER ALGER/NRN
SCHOOLCRAFT COUNTIES...SO THE GOING WRNGS APPEAR ON TRACK. AS WL BE
THE CASE TODAY OVER THE W...HI EQUILIBRIUM LVL AND FAVORABLE UVV MAX
WITHIN THE DGZ WL BE ENHANCING FACTORS FOR SN RATES IN THIS AREA.
ALTHOUGH THE DEPARTURE OF THE DYANAMIC SUPPORT/VERY DEEP MSTR MAY
SLOW DOWN THE HEAVY SN RATES OVER THE W BY THE OVERNGT HRS...
LINGERING CYC NW BACKING TOWARD THE WNW OVER THE FAR W TOWARD 12Z WL
CONTINUE WIDESPREAD SN SHOWERS/CATEGORICAL POPS IN THE FAVORED SN
BELTS THERE. ALTHOUGH THE EXPECTED NW FLOW IS NOT FAVORABLE FOR
MARQUETTE COUNTY...WL CONTINUE THE ADVY FOR THIS AREA GIVEN
POTENTIAL FOR HIER WINDS NEAR THE LK SHORE AND HEAVIER SN IN THE
EASTERN PART OF THE COUNTY. ONCE AGAIN...THE LIGHTEST AND LEAST
WIDESPREAD SN SHOWERS WL BE OVER THE SCENTRAL.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 519 PM EST SUN NOV 16 2014
MONDAY NIGHT...THE MID LEVEL TROUGH OVER CENTRAL UPPER MI AT 00Z/TUE
IS EXPECTED TO MOVE THROUGH NRN LAKE HURON BY TUE MORNING AS THE SFC
TROUGH ALSO SLIDES THROUGH NRN LOWER MICHIGAN. CYCLONIC NW LOW LEVEL
FLOW WILL PREVAIL ACROSS UPPER WITH VERY COLD AIR MOVING IN AS CAA
DROP 850/700 MB TEMPS TO AROUND -17C/-26C. INSTABILITY WILL BE VERY
FAVORALB FOR HEAVY LES WITH LAKE INDUCED CAPE VALUES TO NEAR 1K J/KG
AND EQUILIBRIUM LEVELS TO NEAR 17K FT. STRONG UPWARD MOTION IN THE
3K-6K FT DGZ WILL SUPPORT SLR VALUES AOA 20/1 BUT WILL BE LIMITED BY
FRACTURING/COMPACTION WITH THE STRONG WINDS.
THE MAIN QUESTION WILL BE THE POSITION/DURATION OF THE HEAVY BANDS
WITH THE GRADUALLY SHIFTING WINDS. THE 330 FLOW GRADUALLY BACKING
OVERNIGHT SHOULD BRING THE HEAVIEST SNOW INTO THE WEST FROM IWD TO
ROCKLAND AND INTO ALGER COUNTY OVER THE EAST. SNOWFALL RATES OF AT
LEAST AN INCH OR TWO PER HOUR ARE EXPECTED AT TIMES WITH ADDITIONAL
AMOUNTS OF 4 TO 8 INCHES OVER THE WEST AND TO NEAR 10 INCHES INTO
ALGER AND NW SCHOOLCRAFT COUNTY. THE STRONG WINDS SHOULD ALSO PUSH
SOME OF THE HEAVIER SNOW INTO SRN SCHOOLCRAFT COUNTY. THERE IS MORE
UNCERTAINTY WITH THE SNOWFALL AMOUNTS INTO MARQUETTE COUNTY AS THE
LOW LEVEL WIND LINES UP PARALLEL TO THE SHORELINE FROM BIG BAY TO
MARQUETTE. EXPECT THERE WILL BE A PERIOD WHERE WINDS VEER ENOUGH SO
THAT THE TRAJECTORIES STILL BRING SOME OF THE HEAVIER BANDS INTO THE
NORTH AND EAST PARTS OF THE COUNTY FROM BIG BAY AND THE HURON
MOUNTAINS TO NEGAUNEE AND MARQUETTE. HOWEVER...THERE IS LOWER
CONFIDENCE THAT THE HEAVY BANDS WILL PERSIST LONG ENOUGH TO PRODUCE
WARNING AMOUNTS SNOW TOTALS (8 INCHES OR GREATER IN 12 HOURS). THE
STRONG WINDS GUSTING INTO THE 30 TO 40 MPH RANGE NEAR THE SHORE WILL
PRODUCE CONSIDERABLE BLSN WITH VERY POOR VSBY IN THE HEAVIER BANDS.
TUE...AS THE MID LEVEL TROUGH MOVES AWAY WITH QVECTOR DIV..SUBSIDENCE
AND LOWERING INVERSION HEIGHTS AND STEADILY BACKING LOW LEVEL WINDS
WITH THE APPROACH OF THE SFC RIDGE THE LES WILL DIMINISH...ESPECIALLY
OVER THE WEST. HOWEVER... THE LONGER FETCH INTO THE EAST COULD STILL
SUPPORT ADDITIONAL AMOUNTS IN THE 3 TO 6 INCH RANGE FROM MUNISING
EASTWARD.
TUE NIGHT...WITH THE WINDS BACKING TO WESTERLY THERE MAY BE PERIOD
WHEN LOW LEVEL CONV FAVORS A STRONGER BAND INTO THE KEWEENAW WITH A
BRIEF PERIOD OF HEAVIER SNOW. OTHERWISE...THE LES IS EXPECTED TO END
OVER THE REST OF THE CWA AS WINDS BECOME SW.
WED-THU...A COUPLE OF SHORTWAVE TROUGHS DIVING SE INTO THE NRN LAKES
WILL REINFORCE THE COLD AIR OVER THE REGION AND REINVIGORATE THE LES
FOR LOCATIONS FAVORED BY WNW FLOW. ADDITIONAL HEADLINES MAY
EVENTUALLY BE NEEDED FOR ANOTHER ROUND OF HEAVIER SNOW. AWAY FROM
THE LES SNOWBELTS...THERE MAY ALSO BE SOME LIGHT SNOW SHOWERS WITH
THE SHRTWV AND SFC TROUGH ON WED. HOWEVER...AWAY FROM THE SNOWBELTS
ACCUMULATIONS SHOULD REMAIN LESS THAN AN INCH.
FRI-SAT...A MODERATING TREND IS EXPECTED AS THE PATTERN BECOMES LESS
AMPLIFIED. WAA WITH SW FLOW BY SAT COULD BRING TEMPS BACK TO AROUND
30F...STILL BELOW NORMAL. THERE IS MORE UNCERTAINTY BY SUN AS THE
MODELS SUGGEST AT A SHORTWAVE MOVING OUT OF THE SRN/CNTRL PLAINS AND
ACCOMPANYING AREA OF PCPN COULD AFFECT THE AREA. THE 12Z/16 ECMWF
EVEN BRINGS IN ENOUGH WARM AIR FOR MAINLY RAIN BY SAT NIGHT AND SUN.
HOWEVER...CONFIDENCE IN EITHER PCPN POTENTIAL/TYPE/AMOUNT IS LOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1200 AM EST MON NOV 17 2014
SFC LOW OVER NORTHERN LK SUPERIOR WILL SLIDE EAST THROUGH THE
MORNING WHILE DRAGGING A COLD FRONT OVER UPR MICHIGAN. EXPECT VFR TO
MVFR CONDITIONS TO TREND IFR /MAINLY VSBY/ IN MODERATE TO HEAVY LAKE
EFFECT SNOW SHOWERS BY DAYBREAK THIS MORNING AT KIWD AND KCMX BEHIND
THE FRONT. IFR CONDITIONS WILL CONTINUE THROUGH THE END OF THE TAF
PERIOD WITH SOME LIFR CONDITIONS POSSIBLE DURING HEAVIEST SNOW
SHOWERS. WINDS WILL BECOME GUSTY FM THE NORTHWEST BY THIS AFTN
WITH GUSTS OVER 30 KTS AT THE MORE EXPOSED KCMX LOCATION.
MAINLY MVFR CONDITIONS AT KSAW THROUGH MOST OF THE DAY...BUT WILL GO
FOR IFR VSBY LATE THIS AFTN WITH ARRIVAL OF DEEPER MOISTURE AND
WIDESPREAD SNOW SHOWERS. WINDS WILL BECOME GUSTY BY LATE AFTN AT
KSAW AS WELL...WITH GUSTS OVER 25 KTS INTO THIS EVENING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 314 PM EST SUN NOV 16 2014
LOW PRESSURE WILL CROSS LAKE SUPERIOR TONIGHT INTO MONDAY MORNING
WHILE DEEPENING. THE LOW WILL THEN EXIT THROUGH FAR E ONTARIO
MONDAY AFTERNOON. LOOK FOR GUSTS TO INCREASE TO GALES OF 35-40KTS
OVER PORTIONS OF W LAKE SUPERIOR MONDAY AFTERNOON...BEFORE EXPANDING
TO THE E HALF OF LAKE SUPERIOR LATE MONDAY EVENING THROUGH EARLY
TUESDAY. GALE WATCH HAS BEEN UPGRADED TO A GALE WARNING. A TROUGH
WILL THEN LINGER ACROSS LAKE SUPERIOR THROUGH TUESDAY
MORNING...BEFORE BRIEFLY BEING REPLACED BY A RIDGE TUESDAY AFTERNOON
AND EVENING. ANOTHER TROUGH OVER N MANITOBA ON TUESDAY WILL SLIDE
ACROSS THE UPPER GREAT LAKES LATE TUESDAY NIGHT THROUGH
WEDNESDAY...BEFORE EXITING ACROSS THE ONTARIO AND QUEBEC BORDER
THURSDAY MORNING. HIGH PRESSURE OVER THE N PLAINS ON THURSDAY WILL
DIVE ACROSS THE OHIO VALLEY LATE FRIDAY...EXTENDING A RIDGE OVER THE
UPPER GREAT LAKES ON FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY FROM 9 AM THIS MORNING TO 7 AM EST
TUESDAY FOR MIZ004-084.
LAKE EFFECT SNOW WARNING FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR MIZ006-085.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST /NOON CST/ TUESDAY FOR
MIZ001>003-009.
LAKE EFFECT SNOW ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR MIZ007.
LAKE EFFECT SNOW ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM EST
TUESDAY FOR MIZ005.
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 1 PM EST
TUESDAY FOR MIZ014.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TO 1 PM EST TUESDAY FOR LSZ251-267.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 1 PM EST TUESDAY FOR
LSZ248>250-265-266.
GALE WARNING FROM 1 PM THIS AFTERNOON TO 9 AM EST TUESDAY FOR
LSZ264.
GALE WARNING FROM 1 PM EST /NOON CST/ THIS AFTERNOON TO 4 AM EST
/3 AM CST/ TUESDAY FOR LSZ240>242-263.
GALE WARNING FROM 1 PM THIS AFTERNOON TO 7 AM EST TUESDAY FOR
LSZ243>245.
GALE WARNING FROM 1 PM EST /NOON CST/ THIS AFTERNOON TO 1 AM EST
/MIDNIGHT CST/ TUESDAY FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLB
AVIATION...JLA
MARINE...KF
AREA FORECAST DISCUSSION
NWS GAYLORD MI
335 AM EST MON NOV 17 2014
.SYNOPSIS...
ISSUED AT 331 AM EST MON NOV 17 2014
LOW PRESSURE PASSING TO OUR NORTH TODAY...WILL USHER IN ANOTHER
SURGE OF COLD AIR. LAKE EFFECT SNOW SHOWERS WILL CONTINUE IN SOME
PLACES TODAY...BUT HEAVY SNOW IS EXPECTED TONIGHT AND TUESDAY IN
SOME OF THE CLASSIC SNOWBELTS. ANOTHER SYSTEM WILL BRING LIGHT SNOW
TO THE REGION WEDNESDAY...AND MORE LAKE EFFECT SNOW WILL FOLLOW
BEHIND IT. HOWEVER...TEMPERATURES WILL BECOME MILDER DURING THE
UPCOMING WEEKEND.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 331 AM EST MON NOV 17 2014
...SIGNIFICANT LAKE EFFECT SNOW EVENT EXPECTED LATER TODAY THROUGH
TUESDAY...
HIGH IMPACT WEATHER POTENTIAL: LOCALIZED VERY HEAVY LAKE EFFECT
SNOW. AREAS OF BLOWING SNOW AND NEAR WHITEOUT CONDITIONS POSSIBLE
TONIGHT.
PATTERN SYNOPSIS/CURRENT CONDITIONS: KINDA STATING THE OBVIOUS...BUT
MID-WINTER LIKE PATTERN WELL ESTABLISHED ACROSS THE NORTHERN LAKES.
REASON FOR SUCH IS ONE ANOMALOUSLY DEEP MERIDIONAL FLOW
REGIME...CONSISTING OF FULL LENGTH WESTERN NOAM RIDGING AND JUST AS
IMPRESSIVE TROUGHING EXTENDING THROUGH THE CENTRAL PLAINS INTO THE
WESTERN LAKES. MOST IMPRESSIVE COLD SURGE YET TIED TO WAVE OF ARCTIC
ORIGIN DIVING INTO SOUTHWEST ONTARIO AND INTO MINNESOTA (-20C H8
TEMPERATURES PER LATEST RAP ANALYSIS!). SURFACE COLD FRONT RUNNING
WELL AHEAD OF THIS WAVE...ALREADY PUSHING INTO NORTHWEST MICHIGAN AT
THIS EARLY HOUR. AREA OUT AHEAD OF THIS FRONT PLENTY COLD ENOUGH TO
CONTINUE TO ENTICE A SIGNIFICANT LAKE RESPONSE (A PRETTY RARE FEAT
TO HAVE SUCH COLD PRE-FRONTAL AIR DURING MID NOVEMBER). MAIN SHOW
TONIGHT HAS BEEN DIRECTED INTO PARTS OF EASTERN UPPER MICHIGAN..
WHERE NO DOUBT SEVERAL INCHES OF ACCUMULATION HAVE ALREADY OCCURRED.
SOMEWHAT LIGHTER MORE NUISANCE TYPE SNOWS IMPACTING NORTHER
LOWER...ALTHOUGH SOME EMBEDDED HEAVIER LAKE ENHANCED SNOWS WERE
NOTED...ESPECIALLY ACROSS PARTS OF EMMET COUNTY. SIMPLY NO END IN
SIGHT...WITH CURRENT UPSTREAM WAVE SET TO AMPLIFY OVERHEAD LATER
TODAY AND TONIGHT...FORCING A SHIFTING OF THE WINDS TO MORE W/NW AND
PUTTING THE MORE TRADITIONAL LAKE EFFECT AREAS UNDER THE GUN FOR A
HIGH IMPACT WINTER WEATHER EVENT.
PRIMARY FORECAST CONCERNS/CHALLENGES: MULTIPLE! INITIAL FOCUS ON
ONGOING SW FLOW LAKE EFFECT AND ASSOCIATED HEADLINES THIS MORNING.
OVERNIGHT FOCUS ON MUCH MORE WIDESPREAD LAKE SNOW EVENT...INCLUDING
AMOUNTS AND HEADLINE MANAGEMENT CONCERNS.
DETAILS: NOT PRETTY! FIRST OFF...ONGOING SW FLOW LAKE SNOWS SHOULD
STEADILY DECLINE IN INTENSITY SHORTLY AFTER 09Z AS WINDS BEGIN TO
SLOWLY VEER AND BRIEF CORRIDOR OF UPSTREAM DRIER AIR OVERSPEADS THE
LAKES. CURRENT HEADLINES RUN THROUGH 15Z...WHICH OFFERS SOME
FLEXIBILITY IF BANDS SHOULD PERSIST LONGER THAN ANTICIPATED (NEVER
SEEN THAN BEFORE :)). NO OFFICIAL REPORTS JUST YET...BUT BASED OFF
MACKINAC BRIDGE WEB CAMS AND SOME INFORMATION GLEANED FROM CALLING
ST. IGNACE...GOTTA FEELING WE WILL BE DEALING WITH SOME IMPRESSIVE
SNOWFALL TOTALS UP IN THE STRAITS AREA BEFORE ALL IS SAID AND DONE
THIS MORNING. ELSEWHERE...JUST SOME LIGHTER SNOWS EXPECTED AS THE
COLD FRONT PUSHES EAST...EXITING STAGE RIGHT BY MID-MORNING.
WITH PART ONE DONE...ALL FOCUS SHIFTS TO WHAT INCREASINGLY LOOKS
LIKE A VERY SIGNIFICANT AND PROLONGED LAKE EFFECT EVENT FOR THE MORE
TRADITIONAL SNOW BELTS OF EASTERN UPPER AND NORTHERN LOWER MICHIGAN.
CURRENT SOUTHWEST ONTARIO WAVE CONTINUES TO DIG...SLOWLY CROSSING
THE NORTHERN LAKES THROUGH THE OVERNIGHT. DESPITE MAIN CORE OF
ATTENDANT CAA ACTUALLY PASSING US BY TO THE SOUTH...INSTABILITY
RAMPS UP IMPRESSIVELY LATE TODAY THROUGH THE OVERNIGHT...WITH NEAR
EXTREME DELTA T/S COLLOCATED WITH DEEP SYNOPTIC MOISTURE SUPPORT AND
ESSENTIALLY ALL LOSS OF AN INVERSION. CYCLONIC FLOW IS IMPRESSIVE...
SUGGESTING ENHANCED CONVERGENCE TARGETING NORTHWEST LOWER MICHIGAN.
LOW LEVEL FLOW IS SLIGHTLY MORE BACKED IN RECENT GUIDANCE
RUNS...WELL SUPPORTED BY WHAT SHOULD BE STRENGTHENING LAKE DRIVEN
SURFACE TROUGH DEVELOPMENT. AFTER A BRIEF BREAK THIS AFTERNOON...
EXPECT SNOWS TO GET GOING IN EARNEST THIS EVENING...WITH INITIAL
FOCUS IN FAVORED WEST FLOW AREAS...WITH A SLIGHT SOUTHWARD TREND
EXPECTED DURING THE OVERNIGHT TOWARD THE M-32 CORRIDOR. SNOWFALL
AMOUNTS COULD BE QUITE IMPRESSIVE...WITH STRONG OMEGA CENTERED RIGHT
IN PRIME DGZ RIGHT THROUGH THE OVERNIGHT. DESPITE SOME FRAGMENTATION
OF FLAKES FROM VERY GUSTY WINDS (MORE ON THE WINDS TO
FOLLOW)...EXPECT SNOW TO LIQUID RATIOS TO PUSH 20 TO 1...PERHAPS
EVEN HIGHER IF STRONG LOW LEVEL CONVERGENCE UNDER BANDS HELP
SLACKING THE WIND FIELDS. SLIGHT SOUTHWARD DRIFT LOOKS TO BE THE
ONLY THING FROM PREVENTING SNOW AMOUNTS FROM GETTING TOO OUT OF
HAND. STILL...COULD EASILY SEE PARTS OF
CHARLEVOIX/ANTRIM/OTSEGO/EMMET/CHEBOYGAN COUNTIES EXCEEDING 8 INCHES
BY MORNING...WITH THE HIGHEST AMOUNTS JUST DOWNWIND OF LITTLE
TRAVERSE BAY. ANY SLOWER DRIFT OF BANDS THAN CURRENTLY ANTICIPATED
WILL RESULT IN LOCALLY HIGHER AMOUNTS. FURTHER SOUTH...COMPLETE LACK
OF A LAKE SUPERIOR CONNECTION REALLY SHORTENS THE EFFECTIVE FETCH
LENGTH. SO...DESPITE EXCELLENT INSTABILITY...JUST NOT SEEING THE
OPPORTUNITY FOR A WHOLE LOT OF ACCUMULATION ALONG AND SOUTH OF THE M-
72 CORRIDOR. HOWEVER...GUSTY WINDS OF 20 TO 30 MPH WILL MAKE FOR
SOME NASTY CONDITIONS...CREATING AREAS OF BLOWING AND DRIFTING SNOW
AND BRIEF PERIODS OF VERY LOW VISIBILITIES.
OFF LAKE SUPERIOR: INITIAL FOCUS THIS EVENING LOOKS TO REMAIN WEST
OF WHITEFISH POINT...REALLY TARGETING AREAS OVER NEAR MUNISING AND
SENEY. WINDS BEGIN TO SHIFT MORE W/NW LATE...BRINGING ACCUMULATING
SNOW BANDS INTO NORTHWEST CHIPPEWA COUNTY. LATER START AND SIGNALS
FOR BEST LOW LEVEL CONVERGENCE TO REMAIN OFF TO THE WEST SUGGESTS
LOWER SNOW TOTALS THAN THOSE TO THE SOUTH...WITH 2 TO 4 INCHES
EXPECTED BY MORNING. STRONG WINDS WILL PUSH BANDS FURTHER INLAND
THAN WHAT IS NORMAL...PERHAPS EVEN BRINGING PARTS OF NORTHWEST
MACKINAC COUNTY SEVERAL INCHES BY MORNING.
MORE SNOW WILL FALL IN ALL THE ABOVE AREAS TOMORROW...WITH SEVERAL
MORE INCHES EXPECTED (SEE LONG TERM SECTION BELOW).
HEADLINES: FOR NORTHERN LOWER...GIVEN GUSTY WINDS AND WHAT COULD BE
WIDESPREAD BLOWING SNOW EVEN OUTSIDE THE BETTER SNOW BANDS...HAVE
DECIDED TO FORGO THE SPECIFIC LAKE EFFECT HEADLINES FOR MORE GENERIC
WINTER WEATHER HEADLINES. HIGHEST SNOW TOTAL AREA MENTIONED EARLIER
WILL BE UPGRADED TO A WINTER STORM WARNING...STARTING AT 00Z THIS
EVENING RUNNING RIGHT THROUGH TUESDAY. WINTER WEATHER ADVISORIES
SHOULD DO FOR AREAS SOUTH OF M-72...AS WELL AS PARTS OF NORTHEAST
LOWER AS STRONG WINDS HELP PUSH WEAKENING BANDS FAR INLAND.
&&
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 331 AM EST MON NOV 17 2014
HIGH IMPACT WEATHER POTENTIAL...PLENTY OF SNOW AND COLD DURING THE
WORK WEEK. HEAVY LAKE EFFECT SNOW IN WNW/NW FLOW TUESDAY. SOME
POTENTIAL FOR HEAVY LAKE EFFECT SNOW WED NIGHT TO THU NIGHT.
TUESDAY...UPPER LOW WILL EJECT FROM NORTH OF LAKE HURON INTO EASTERN
QUEBEC. ONE TRAILING SHORTWAVE WILL CROSS CENTRAL LOWER MI IN THE
AFTERNOON...ANOTHER WEAK WAVE WILL DIG TOWARD EASTERN SUPERIOR. A
980MB SURFACE LOW STARTS THE MORNING IN CENTRAL QUEBEC...AND WILL
ADVANCE NE. SUBSTANTIAL TROFFING LINGERS ACROSS THE AREA EARLY IN
THE MORNING...THIS RELAXES AS THE UPPER LOW PULLS OUT...BUT LAKE-
INDUCED TROFFING REMAINS EVIDENT THRU THE DAY.
1000-850MB WINDS REMAIN STEADY-STATE IN THE MORNING...WNW INTO
NORTHERN LOWER AND NW INTO EASTERN UPPER. WINDS WILL BACK SOME
DURING THE AFTERNOON...BY EARLY EVENING WE WILL SEE A W FETCH INTO
NORTHERN LOWER AND WNW INTO EASTERN UPPER. PLENTY OF DEEP
MOISTURE...HIGH INVERSION HEIGHTS (TO NEARLY 500MB)...AND DELTA T/S
NEAR 20C SHOULD ENSURE RAMPAGING LAKE EFFECT SNOW IN THE MORNING
HOURS. IN THE AFTERNOON...THE INVERSION LOWERS TOWARD 700MB WITH
DRYING ALOFT. THAT WILL REDUCE SNOW INTENSITY SOMEWHAT...BUT BY AND
LARGE PARAMETERS AND STILL VERY FAVORABLE.
AS IS THE CASE FOR TONIGHT...THE LOW-LEVEL FLOW IS A LITTLE BACKED
COMPARED TO PREVIOUS RUNS. IN NORTHERN LOWER...THIS REQUIRES
ADJUSTING THE MAX SNOW TOTALS NORTHWARD SLIGHTLY.
CHARLEVOIX/ANTRIM/OTSEGO ARE THE MAIN ONES UNDER THE GUN...BUT THE
FETCH NOW SUPPORTS MORE SNOW IN SOUTHERN EMMET/CHEBOYGAN THAN IT
DOES IN NORTHERN KALKASKA/CRAWFORD. 5-9 INCHES STILL LIKES A GOOD
FORECAST FOR THE DAY IN THE HARDEST-HIT LOCALES...CENTERED ON
ELMIRA. 1-4 INCHES WORKS ELSEWHERE IN NW LOWER...WHERE THE FETCH IS
MUCH SHORTER AND HAS NO CONNECTION TO SUPERIOR.
IN EASTERN UPPER...THE BACKED FLOW OPENS UP MORE OF CHIPPEWA...BUT
SHOULD STILL KEEP THE STRONGEST BANDS WEST OF THE SAULT. BUT THINGS
ARE LOOKING CONSIDERABLY MORE FAVORABLE UP THERE...AND WILL INCREASE
WESTERN CHIP AND FAR NW MACK INTO THE 3-5 INCH RANGE.
MAX TEMPS WILL BE MAINLY IN THE 20S. HOWEVER...IN THE HIGH TERRAIN
IN THE SOUTH...WHERE MARINE MODIFICATION WILL BE SMALLER DUE TO THE
SHORTER FETCH...SOME PLACES (LIKE CAD) WILL LIKELY NOT ESCAPE THE
TEENS. (HARD TO BELIEVE IT/S ONLY MID-NOVEMBER.)
TUE NIGHT/WED...NOT MUCH REST FOR THE SNOW-WEARY. CLIPPER SHORTWAVE
WILL ADVANCE INTO THE WESTERN LAKES ON WED. ASSOCIATED SURFACE LOW
WILL ADVANCE FROM THE UPPER MS VALLEY TO NORTHERN LOWER MI ON WED.
LOW LEVEL FLOW WILL BACK TO THE SW TUE NIGHT...WITH MOISTENING
OVERNIGHT. SOME POTENTIAL FOR SOME SNEAKY 1-3 INCH ACCUMS OVER THE
TIP OF NORTHERN LOWER TUE EVENING. SYNOPTIC -SN MIGHT SNEAK INTO SW
SECTIONS LATE TUE NIGHT...BUT THE BULK OF THE THAT WILL WAIT UNTIL
WED. BY THEN...A SOUTH 1000-850MB FETCH SHOULD KEEP MOST OF THE LAKE-
INDUCED NONSENSE AT BAY...OTHER THAN ALONG THE SOUTH SHORE OF UPPER
MI (AND IT IS UNCERTAIN WHETHER SYNOPTIC PRECIP WILL MAKE IT THAT
FAR NORTH). THIS SYSTEM DOES NOT LOOK LIKE A MAJOR PROBLEM...1-2
INCHES...ESPECIALLY SOUTH OF M-32. MIN TEMPS TEENS TO PERHAPS HIGH
SINGLE DIGITS (YIKES). MAX TEMPS 20S.
REST OF THE FORECAST...POST-CLIPPER LAKE EFFECT SNOW WILL OCCUR WED
NIGHT INTO THU NIGHT...AIDED BY ANOTHER CLIPPER SHORTWAVE DROPPING
IN FROM THE NW. THE SET-UP FOR HEAVY SNOW LOOKS BETTER IN EASTERN
UPPER IN THIS EVENT...AS DEEPER MOISTURE WILL LINGER LONGER THERE VS
MID-LEVEL DRY AIR TRYING TO ENTRAIN INTO THE SOUTHER/CENTRAL LAKES.
REGARDLESS...LAKE EFFECT SHSN WILL AGAIN BE FAIRLY WIDESPREAD IN
BOTH PENINSULAS.
THOUGH THE MODELS TEND TO BE TOO FAST TO BREAK PATTERNS DOWN...ALL
MODELS HAVE THE CURRENT ONE FALL APART AFTER THIS LAST CLIPPER.
500MB FLOW BECOMES CONSIDERABLY MORE ZONAL...AND MORE SEASONABLE AIR
WILL FINALLY GET A CHANCE TO MOVE INTO THE REGION...ESPECIALLY BY
THE TAIL END OF THE WEEKEND. A SOUTHERN STREAM SYSTEM MOVING INTO
THE CENTRAL STATES WILL AMPLIFY WARM ADVECTION...AND INCREASE PRECIP
CHANCES BY SUNDAY. THIS ACTUALLY LOOKS TO BE MOSTLY RAIN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1145 PM EST SUN NOV 16 2014
S/SW FLOW LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO TARGET OUR NW
LWR MICHIGAN TAF SITES (PLN/TVC/MBL)THROUGH MONDAY...DROPPING
CONDITIONS TO IFR WITHIN HEAVIER SNOW BANDS. APN WILL REMAIN VFR
THRU MONDAY AWAY FROM THE LAKE SNOW SHOWERS...WITH JUST A PASSING
LIGHT SNOW SHOWER EXPECTED. S/SW WINDS WILL REMAIN AOB 10 KTS THRU
THE FORECAST PERIOD.
&&
.MARINE...
ISSUED AT 331 AM EST MON NOV 17 2014
STRONG SURGE OF CAA AND INCREASINGLY SHARP PRESSURE
GRADIENT WILL BRING VERY GUSTY WINDS BY LATER TODAY RIGHT THROUGH
TUESDAY. GREATEST IMPACT EXPECTED ACROSS NORTHERN LAKE
MICHIGAN...WHERE GALE FORCE WEST WINDS ARE EXPECTED TO DEVELOP
QUICKLY THIS EVENING. SCA CONDITIONS EXPECTED ELSEWHERE...ALTHOUGH
WILL NEED TO BE ON THE LOOKOUT FOR SOME GALE GUSTS ALONG THE
NORTHEAST LOWER COASTLINE. WINDS ARE EXPECTED TO SUBSIDE LATE
TUESDAY...AND ESPECIALLY TUESDAY NIGHT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST
TUESDAY FOR MIZ018-020-023-025>028-031>033.
WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM EST TUESDAY
FOR MIZ016-017-019-021-022.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MIZ008-016.
WINTER WEATHER ADVISORY FROM 1 AM TO 7 PM EST TUESDAY FOR MIZ008.
LAKE EFFECT SNOW WARNING UNTIL 10 AM EST THIS MORNING FOR MIZ015.
LH...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR LMZ341.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 7 PM EST TUESDAY FOR
LMZ323-342-344>346.
LS...SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING TO 7 PM EST TUESDAY
FOR LSZ321-322.
&&
$$
SYNOPSIS...JAZ
SHORT TERM...MSB
LONG TERM...JAZ
AVIATION...MLR
MARINE...MSB
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1122 PM CST Sun Nov 16 2014
.UPDATE:
Issued at 923 PM CST Sun Nov 16 2014
Accumulating snow has ended across the area allowing the winter
weather advisory to expire at 9 pm. The band of accumulating snow
continues just south of the CWA which is being forced by strong
frontogenesis that will eventually shift southeast tonight. Some
snow may still occur along and south of a Fredericktown to Salem,
IL line on the northern periphery of this area of snow before
08Z per the HRRR, but any accumulation is expected to be minor.
Temperatures are falling into the teens over northeast Missouri,
and decent cold air advection should allow most of the area to
fall into the teens before sunrise.
Britt
&&
.SHORT TERM: (Through Late Tonight)
Issued at 345 PM CST Sun Nov 16 2014
Snow is clearing from the west to east this afternoon, and latest
short-range guidance shows that it should continue to push east at a
decent clip through early evening. RAP and HRRR have done a very
good job with this system (as they did with yesterday`s
precipitation) so am following them closely. The surface cold front
which currently looks to be along a line from near Pittsfield to
near the Lake of the Ozarks, will push slowly eastward tonight.
While accumulating snow should end across most of the area by
00-02Z, some flurries could linger along and east of the Mississippi
from St. Louis southward until the cold front finally pushes through
bringing drier low level air to the area. An additional 1-2 inches
of snow with locally higher amounts is still possible until the
snow ends...primarily on elevated surfaces. Based on current obs
and latest radar trends, will be dropping the advisory west and
north of the STL area, while continuing the advisory into the
early evening hours over southeast sections of the CWA.
Guidance appears to have a reasonable handle on overnight lows.
Leading edge of the first round of Arctic air (as defined by
single digits dewpoints) currently entering northwest sections of
the CWA, and this will be followed by a secondary surge of Arctic
air (now working into the mid-Missouri Valley) that will enter the
CWA during the predawn hours. In this situation guidance has a tendency
to be a bit too cool due to mixing and some clouds, but due to the
shear strength of cold air in this situation believe "thinking
cold" is the way to go.
Carney/Truett
.LONG TERM: (Monday through Next Sunday)
Issued at 313 PM CST Sun Nov 16 2014
Monday-Wednesday
Deep and unseasonably strong UA trof over the eastern half of the
CONUS will mean more unseasonably cold November temperatures in
our area through midweek. Obviously, temperature specifics are
going to be the main forecast problem in the short term, and going
forecasts appear to have a fairly good handle on the expected
trends.
Secondary surge of Arctic air that enters the FA late tonight
will be a much colder airmass than any we`ve experienced during
this early taste of winter, and there is good agreement in the 12z
synoptic runs that 850mb temps of -18 to -20C will be common over
the mid-Mississippi Valley by Monday evening. Low level RH progs
suggest quite a bit of low level cloudiness overspreading the area
on Monday in the wake of the secondary cold front, and this cloud
cover combined with the very cold airmass will almost certainly
mean highs only in the 20s for most of the CWA. Perhaps the
biggest question is Monday night. While airmass is extremely cold
for this time of year and there may be snow on the ground in some
locations over the southeast half of the CWA, the center of the
Arctic high is forecast to drop from the Plains into the Arklatex
region. The resultant pressure gradient in our area should mean
that westerly winds will persist throughout much of the night,
with this mixing keeping low temps from reaching record levels.
Normally in this situation would be worried about climo bias
causing guidance to be too warm, but due to the aforementioned
winds and mixing believe it may have a good handle on Monday
night temp trends at this point in time. See climate section for
more info on record lows/record low max temps for the next few
days/nights.
AMS moderation will begin on Tuesday as the center of the Arctic
high works its way in the the se U.S., with additional warming on
Wednesday due to warm advection ahead of next shortwave.
Precipitation threat over the next few days should be limited to a
few flurries with the arrival of the cold air and low clouds
tomorrow.
Thursday-Sunday
Another shot of cold air will settle into the region in the wake of
Wednesday`s shortwave. However, this next round of cold air will
not be nearly as strong as the Arctic airmass that invades the region
tomorrow and tomorrow night, and as a result it`s impact on late
week temps will not be nearly as dramatic.
Temperatures will moderate heading into next weekend as trof axis
works east and allows a more zonal flow regime to develop over the
nation`s heartland. Resultant low level warm advection/isentropic
ascent, combined with an approach of an upper level trof in the
southern branch of the westerlies, should mean a chance of
precipitation. Last several medium range runs, as well as latest
12z guidance, suggests ams will warm enough that the bulk of this
precip will be in liquid form.
Truett
&&
.AVIATION: (For the 06z TAFs through 06z Monday Night)
Issued at 1121 PM CST Sun Nov 16 2014
Vfr conditions have returned to the taf sites, though some
lingering mvfr cigs around KCPS through 07z. Otherwise, northwest
winds to pickup by mid morning with gusts to near 25kts at times.
Will see sc develop on back side of system, so kept tempo mention
of mvfr cigs through the afternoon hours before scattering out
towards sunset. Winds will diminish towards sunset as well.
Specifics for KSTL:
Vfr conditions have returned to the metro area, though some
lingering mvfr cigs around KCPS through 07z. Otherwise, northwest
winds to pickup by 16z Monday with gusts to near 25kts at times.
Will see sc develop on back side of system, so kept tempo mention
of mvfr cigs through the afternoon hours before scattering out
towards sunset. Winds will diminish towards sunset as well.
Byrd
&&
.CLIMATE:
The following are record low maximums and record low minimums for
each of the next 3 days, which corresponds to the expected length
of the current cold spell and record snowfall for St. Louis and
Columbia for Sunday and Monday.
Date: 11/16 11/17 11/18
St. Louis
Low High: 29/1997 17/1880 25/1880
Low: 13/1959 6/1959 14/1932
Snowfall: 0.1/1997 1.0/1951
Columbia
Low High: 30/1932 23/1959 27/1903
Low: 8/1959 4/1959 8/1891
Snowfall: 4.8/1932 0.1/1989
Quincy
Low High: 28/1997 19/1959 24/1903
Low: 4/1959 3/1959 7/1903
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BISMARCK ND
335 AM CST MON NOV 17 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 334 AM CST MON NOV 17 2014
HUDSON BAY UPPER LOW WITH SUCCESSIVE SHORTWAVE TROUGHS ROTATING
AROUND HAS CARVED OUT A SIGNIFICANT UPPER TROUGH EXTENDING SOUTH
INTO THE MIDWEST AND SOUTHERN PLAINS PER LATEST WATER VAPOR
IMAGERY. NORTHERLY FLOW INTO NORTH DAKOTA WITH ANOTHER MINOR
SHORTWAVE NOW LOCATED JUST WEST OF LAKE WINNIPEG IS FORECAST TO
REACH INTO THE BISMARCK VICINITY BY 18Z TODAY. THE LATEST
FOG/STRATUS LOOP SHOWS CLOUDS AND FLURRIES OVER THE
SOUTHWEST...WHICH EXTENDS ACROSS MOST OF EASTERN MONTANA. FARTHER
UPSTREAM CLOSER TO THE LOCATION OF THE INCOMING SHORTWAVE...QUITE
A BIT OF CLOUDS PUSHING SOUTH. THE LATEST HRRR REINFORCES CLOUDS
ESPECIALLY IN THE WEST...BUT THINK THE CENTRAL WILL ALSO CLOUD UP
DURING THE LATE MORNING AND EARLY AFTERNOON. THE HIGH RESOLUTION
ARW AND NMM MODELS CONTINUE WITH THE FLURRIES WEST THROUGH 18Z
TODAY AND HAVE FOLLOWED THIS AS THEY ARE VERIFYING THE BEST EARLY
THIS MORNING WITH THE CURRENT ACTIVITY. WARM AIR ADVECTION
COMMENCES MONDAY NIGHT WITH A PUSH OF H7-H5 MOISTURE. THIS WILL
PROGRESS FROM WEST TO EAST OVERNIGHT RESULTING IN PARTLY CLOUDY
CONDITIONS. HIGHS TODAY WILL RANGE FROM 10F TO 15F WITH OVERNIGHT
LOWS BETWEEN 3 BELOW ZERO TO 3 ABOVE.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 334 AM CST MON NOV 17 2014
A POTENTIAL MODERATION IN TEMPERATURES LATE THIS WEEK HIGHLIGHTS
THE EXTENDED FORECAST.
THE 00 UTC SUITE IS IN AGREEMENT ON THE ANOMALOUS HIGH AMPLITUDE
UPPER LEVEL PATTERN ACROSS NORTH AMERICA BREAKING DOWN TO A NEAR
ZONAL PATTERN BY NEXT WEEKEND IN A BROAD VERY LOW AMPLITUDE
TROUGH. THIS WOULD SIGNAL A RECOVERY FROM THE ARCTIC TEMPERATURES
TO STILL BELOW NORMAL...YET MORE TOLERABLE HIGHS NEAR FREEZING
FRIDAY INTO THE WEEKEND. THE EXTENDED FORECAST LOOKS TO BE LARGELY
PRECIPITATION FREE...WITH SPLIT FLOW DEVELOPING AND THE LACK OF
MOISTURE RECOVERY FROM THE ARCTIC AIRMASS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 334 AM CST MON NOV 17 2014
CIGS WILL VARY BETWEEN VFR AT KISN/KDIK TO MVFR CONDITIONS DURING
THE DAY MONDAY. PERIODIC LOW VFR CIGS ARE FORECAST AT KBIS/KMOT
WITH VFR AT KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1128 PM CST SUN NOV 16 2014
.AVIATION...
/06Z TAFS/
GUSTY NORTHERLY WINDS UP TO 25 KNOTS WILL PERSIST OVERNIGHT
ACROSS SOUTH CENTRAL TEXAS. MVFR CONDITIONS WILL LINGER AROUND TO
ABOUT 09Z MONDAY MAINLY ALONG THE I-35 CORRIDOR SITES. ACROSS KDRT...
VFR CONDITIONS ARE ANTICIPATED FOR THE ENTIRE FORECAST CYCLE. CIGS
WILL LIFT TO VFR EARLY MONDAY MORNING AND CONTINUE THAT WAY FOR
THE REMAINDER OF THE FORECAST PERIOD. BREEZY NORTHERLY WINDS WILL
REMAIN THROUGH MONDAY EVENING.
&&
.PREV DISCUSSION... /ISSUED 751 PM CST SUN NOV 16 2014/
UPDATE...
THE COLD FRONT IS NOW LOCATED ACROSS OUR SOUTHERN COUNTIES. MUCH
COLDER WEATHER IS MOVING IN BEHIND THE BOUNDARY AND AT 8 PM THE
FREEZING LINE WAS JUST ENTERING OUR NORTHERN COUNTIES NEAR EDWARDS
AND KERR COUNTY. A LARGE AREA OF VERY LIGHT PRECIPITATION REMAINS
CONFINED TO AREAS NORTH OF OUR CWA AND THIS SHOULD CONTINUE TO BE
THE CASE FOR MOST OF THE NIGHT. THIS AFTERNOON THE HRRR HAD BEEN
SHOWING A BAND OF PRECIP PUSHING THROUGH SOUTH-CENTRAL TEXAS BUT
HAS SINCE BACKED OFF. THE BEST CHANCES FOR WINTER PRECIP TONIGHT
WILL BE IN THE NORTHERN HILL COUNTRY...NEAR LLANO AND BURNET
COUNTY THROUGH MIDNIGHT. CURRENTLY...A BAND OF SNOWFALL EXTENDS
SOUTH NEAR ELDORADO AND WITH A CONTINUED EASTWARD MOVEMENT THIS
WOULD QUICKLY CLIP LLANO AND BURNET COUNTIES. THE QUESTION THEN
TURNS INTO WHAT THE PRECIPITATION TYPE WOULD BE. ALL MODEL
FORECAST SOUNDINGS SHOW A WARM LAYER AROUND 750 MB THAT WOULD
LIKELY PREVENT SNOW THIS FAR SOUTH. HOWEVER...A FAIRLY DEEP SUB-
FREEZING LAYER BELOW 800 WOULD LEAD TO A SLEET/RAIN MIX OR ALL
SLEET. IF MODELS ARE OVERDOING THIS WARM LAYER...THEN BRIEF SNOW
WOULD BE POSSIBLE. AM NOT EXPECTING ACTIVITY TO BE HEAVY OR LAST
FOR A VERY LONG TIME SO THERE SHOULD NOT BE MANY IMPACTS. SINCE IT
WILL BE SUCH A SHORT-TERM TYPE EVENT WILL MOST LIKELY HANDLE ANY
IMPACTS WITH AN SPS LATER THIS EVENING IF NEEDED. MODEL SOUNDINGS
SHOW A LOT OF DRYING IN THE LOW-LEVELS AFTER 6Z AND MUCH OF THE
PRECIP SHOULD SHUT OFF. THE HRRR IS SHOWING THIS WELL.
HAMPSHIRE
PREV DISCUSSION... /ISSUED 507 PM CST SUN NOV 16 2014/
AVIATION...
A COLD FRONT IS PUSHING ACROSS THE AREA LATE THIS AFTERNOON. THE
COLD FRONT IS LOCATED SOUTH OF HIGHWAY 90 ACROSS OUR SOUTHERN COUNTIES
AND EXPECTED TO PUSH AWAY FROM OUR AREA EARLY THIS EVENING. IN THE WAKE OF
THE FROPA...BREEZY NORTHERLY WINDS WILL PREVAIL FOR MOST OF TONIGHT.
ALSO...GUSTY WINDS UP TO 30 KNOTS ARE POSSIBLE THROUGH ABOUT
MIDNIGHT TONIGHT. CIGS AND VSBYS WILL IMPROVE TO MVFR THIS EVENING AND
THEN BECOMING VFR OVERNIGHT/EARLY MONDAY. CLEARING IS FORECAST
ACROSS AREA SITES MONDAY MORNING WITH NORTHERLY WINDS OF 8 TO 12 KNOTS.
PREV DISCUSSION... /ISSUED 330 PM CST SUN NOV 16 2014/
SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...
UPPER AIR ANALYSIS THIS MORNING SHOWED A TROUGH SWINGING THROUGH
THE SOUTHWEST WITH SOUTHWESTERN FLOW ACROSS TEXAS. AT THE SURFACE
A COLD FRONT WAS ENTERING OUR CWA THIS AFTERNOON. IT STRETCHED
FROM WACO TO JUNCTION TO LANGTRY. THERE HAS ONLY BEEN ISOLATED
LIGHT RAIN WITH THE FRONT AND THE MAIN CHANGE IS THE STRONG NORTH
WINDS. THERE WAS MORE WIDESPREAD PRECIP ASSOCIATED WITH A SHORT
WAVE TROUGH MOVING INTO WEST TEXAS. THESE FEATURE WILL MOVE TOWARD
OUR FORECAST AREA LATER TONIGHT AND MODELS SUGGEST THAT WE WILL BE
ON THE SOUTHERN EDGE OF IT. WE WILL HAVE SLIGHT TO LOW END CHANCE
POPS THIS EVENING ACROSS OUR EASTERN COUNTIES. WITHIN THIS AREA
THERE WILL A CHANCE FOR SOME WINTER PRECIP IN PARTS OF BURNET AND
WILLIAMSON COUNTIES. IT LOOKS LIKE THE MOST LIKELY SCENARIO IS FOR
A MIX OF RAIN AND SLEET AND THE BEST TIME WILL BE BETWEEN ABOUT
9PM AND MIDNIGHT. PRECIP AMOUNTS SHOULD BE LIGHT AND WITH THE
GROUND SO WARM WE DO NOT EXPECT ANY WINTER PRECIP TO HAVE ANY
IMPACTS TONIGHT. AFTER MIDNIGHT PRECIP CHANCES WILL SHIFT TO THE
SOUTH WHERE TEMPERATURES WILL STAY ABOVE FREEZING SO WE ONLY HAVE
RAIN IN THE FORECAST. MORNING LOW TEMPERATURES WILL DROP TO OR
BELOW FREEZING ACROSS THE HILL COUNTRY AND EDWARDS PLATEAU. MONDAY
THE FRONT WILL MOVE AWAY AND THE UPPER TROUGH WILL SWING THROUGH
THE REGION. EXPECT SKIES TO CLEAR THROUGH THE DAY. CLEAR SKIES AND
LIGHT WINDS WILL ALLOW FOR GOOD RADIATIONAL COOLING MONDAY NIGHT
AND A WIDESPREAD FREEZE. EXPECT THAT A FREEZE WARNING WILL BE
NEEDED FOR THE PARTS OF THE CWA THAT HAVE NOT YET HAD A FREEZE.
LONG TERM (TUESDAY THROUGH SUNDAY)...
THE UPPER PATTERN WILL BECOME MORE ZONAL INTO THE MIDDLE OF THE
WEEK AS THE LOW LEVEL FLOW TURNS BACK TO THE SOUTHEAST. THIS WILL
LEAD TO A WARMING TREND INTO THURSDAY. BY THURSDAY AN OVER RUNNING
PATTERN WILL BECOME ESTABLISHED ACROSS THE EASTERN HALF OF THE
AREA. THERE WILL BE SLIGHT TO LOW END CHANCE POPS STARTING THURSDAY
AND CONTINUING THROUGH THE END OF THE PERIOD. THIS SEEMS LIKE TOO
LONG A PERIOD FOR RAIN EVEN THOUGH CHANCES WILL BE LOW. TIME FRAME
SHOULD COME INTO BETTER FOCUS AS WE GET CLOSER.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 33 50 29 53 36 / 20 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 33 51 24 53 32 / 20 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 33 53 28 54 35 / 20 0 0 0 10
BURNET MUNI AIRPORT 29 48 27 52 32 / 20 0 0 0 0
DEL RIO INTL AIRPORT 34 53 31 53 35 / 10 0 0 0 0
GEORGETOWN MUNI AIRPORT 31 49 25 52 33 / 20 0 0 0 0
HONDO MUNI AIRPORT 32 52 25 52 34 / 10 0 0 0 10
SAN MARCOS MUNI AIRPORT 33 52 26 53 33 / 20 0 0 0 10
LA GRANGE - FAYETTE REGIONAL 34 50 27 52 34 / 30 0 - - 10
SAN ANTONIO INTL AIRPORT 35 53 29 53 38 / 10 0 0 0 10
STINSON MUNI AIRPORT 36 53 29 54 37 / 10 0 0 0 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...17
SYNOPTIC/GRIDS...29
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
405 AM EST MON NOV 17 2014
.SYNOPSIS...
A STRONG COLD FRONT SWINGS ACROSS THE AREA TODAY. ARCTIC AIR WILL
FOLLOW TONIGHT WITH HIGH PRESSURE MOVING INTO THE MID MISSISSIPPI
VALLEY. EXPECT A PERIOD OF SNOW SHOWERS...WINDS AND COLD WIND
CHILLS LATE TONIGHT INTO TUESDAY MORNING AS A RESULT.
HIGH PRESSURE BUILDS ACROSS THE SOUTHEAST INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 330 AM EST MONDAY...
EARLIER RUN OF THE HRRR HAD A GREAT HANDLE ON THE RAIN MOVING IN
FROM THE SOUTHWEST. FOLLOWED ITS SOLUTION THROUGH THE
MORNING...BLENDING IN THE 00Z GFS/NAM. LOOKS LIKE A SLAM DUNK FOR
EVERYONE SEEING RAIN TODAY...THOUGH AMOUNTS MAY BE LESS THAN EARLIER
THOUGHT AS DID NOT SEE AS MUCH FALL SUNDAY.
STILL A GOOD ONE HALF TO THREE QUARTERS OF AN INCH WILL OCCUR TODAY.
THIS FRONT LOCATED ACROSS THE CENTRAL APPALACHIANS SOUTHWEST INTO
ALABAMA WILL SLIDE EAST ACROSS THE AREA TODAY...WITH A COUPLE WAVES
OF LOW PRESSURE ALONG IT. THE MAIN FORECAST ISSUE WILL BE THE COLDER
AIR ARRIVING BEHIND THE FRONT. THE 00Z NAM DEPICTED THE COLDER AIR
BETTER AT 06Z AT 8H THAN THE GFS/ECMWF...SO LEANED TOWARD IT TEMP
FORECAST. SHOULD SEE DEEP MOISTURE EDGE EAST EARLY THIS AFTERNOON IN
THE MTNS WHILE THE COLDER AIR STARTS TURNING RESIDUAL SHOWERS OVER
TO SNOW LATER IN THE AFTERNOON. BY DUSK MOST OF THE EASTERN HALF OF
THE CWA WILL BE DRYING OUT AS WINDS TURN WNW. TEMPS DESPITE THE
RAIN...OR REALLY AS A RESULT OF THE RAIN BRINGING DOWN THE WARMER
TEMPS ALOFT MAY BRING READINGS INTO THE 50S BEFORE THE COLD AIR
ARRIVES IN THE PIEDMONT THIS AFTERNOON. IN THE MTNS HIGHS SHOULD BE
OCCURRING BY MIDDAY THEN DROPPING IN THE LATE AFTERNOON.
FORECAST SOUNDINGS IN THE MTNS SHOW MOISTURE BECOMING SHALLOW
FAST...WITH THE FAVORABLE SNOW GROWTH TEMPS ALOFT NOT BEING REALIZED
UNTIL LATE EVENING...SO COULD BE SOME PATCHY FREEZING DRIZZLE
ISSUES...AND WILL ADVERTISE THIS IN THE MTNS OF THE FAR WEST THIS
EVENING. THIS HERE LIES THE PROBLEM...WHERE IT RAINS...COMBINED WITH
ARCTIC AIR ARRIVING AND SNIZZLE(SNOW AND FREEZING DRIZZLE)
FOLLOWING...ROADS WILL BECOME SLICK IN THE HIGHER ELEVATIONS BY LATE
DUSK. AFTER COLLABORATING WITH NEIGHBORING OFFICES...IT WAS DECIDED
TO GO WITH A WINTER WX ADVISORY FOR THE NC MTNS INTO THE GRAYSON
HIGHLANDS...BUT TO DELAY ANY HEADLINES...IF THEY ARE NEEDED FURTHER
NORTH INTO THE MTN EMPIRE OF SW VA AND SE WV MTNS. STILL THINK THE
TEMPS FALLING FAST LATE TONIGHT MAY REQUIRE AT LEAST A SPECIAL WX
STATEMENT. THE SNOWFALL ACCUMULATION WILL BE LIGHT GIVEN THE LIMITED
MOISTURE BUT 1 TO 3 INCHES IN THE WESTERN SLOPES ARE POSSIBLE INTO
TUESDAY MORNING.
IN ADDITION...THE WINDS WILL BE GUSTING OVER 40 MPH WITH 6 HR
PRESSURE RISES OF 5-7MB EXPECTED BEHIND THE FRONT THIS EVENING INTO
TUESDAY MORNING. THIS WAS ADDED TO THE WINTER WX ADVISORY IN THE NC
MTNS. CLOUDS MAY PREVENT IDEAL MIXING OF THE STRONGER WINDS
ALOFT...BUT WHERE IT THE CLOUD/CLEARING LINE IS ALONG/NEAR THE BLUE
RIDGE...THINK AN OCCASIONAL 50 MPH GUST WILL BE REALIZED. OUTSIDE
THE WINTER WX ADVISORY FOR ELEVATIONS ABOVE 3000 FT...HIGHLIGHT
WEATHER IN THE HAZARDOUS WEATHER OUTLOOK. WILL TAKE A LOOK AT MORE
DATA COMING IN AND FURTHER COORDINATING WITH OTHER WFO OFFICES TO
SEE IF MORE HEADLINES ARE NEEDED.
FOR TONIGHT...TEMPS WILL DROP INTO THE TEENS MOUNTAINS...SOME SINGLE
DIGITS HIGHEST ELEVATIONS...WITH 20S IN THE EAST. WIND CHILLS BY
DAWN TUESDAY WILL RANGE FROM 5 ABOVE TO 5 BELOW IN THE
MOUNTAINS...TO THE TEENS IN THE EAST.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 315 AM EST MONDAY...
COLD FRONT PUSHES OUT INTO THE ATLANTIC OCEAN TUESDAY AS THE 1033
SURFACE HIGH PRESSURE IN TEXAS BUILDS NORTHWARD INTO OUR REGION. THE
AXIS OF THE UPPER TROF CROSS OUR AREA TUESDAY INTO TUESDAY NIGHT.
GUSTY NORTHWEST WINDS WILL CONTINUE TUESDAY AS A TIGHT PRESSURE
GRADIENT WILL REMAIN OVER THE REGION THROUGH TUESDAY. THE GFS...NAM
AND HIRESW-ARW SHOWED UPSLOPE SNOW SHOWERS AND SNOW FLURRIES
CONTINUE IN THE WESTERN MOUNTAINS. ADDITIONAL LIGHT ACCUMULATIONS
MAY BE POSSIBLE IN THE NORTHWEST UPSLOPE FAVORED LOCATIONS. HIGH
TEMPERATURES TUESDAY WILL RANGE FROM THE UPPER TEENS IN THE
NORTHWEST MOUNTAINS TO THE MID 30S IN THE PIEDMONT. HIGH PRESSURE
CONTINUES TRAVEL EASTWARD TUESDAY NIGHT. TUESDAY NIGHT WILL BE A
VERY COLD NIGHT WITH TEMPERATURES ACROSS THE AREA RANGING FROM THE
SINGLE DIGITS IN THE HIGHER ELEVATIONS TO THE UPPER TEENS ACROSS THE
PIEDMONT. WINDS WILL DECREASE TUESDAY NIGHT...BUT WIND CHILLS WILL
BE COLD WITH SINGLE DIGITS IN THE WEST TO TEENS IN THE EAST.
A WARM FRONT WILL PASS OVER THE REGION WEDNESDAY...AS A COLD FRONT
DROPS SOUTH INTO THE OHIO VALLEY. WEDNESDAY AFTERNOON HIGH
TEMPERATURES WILL AVERAGE 20F COLDER THAN NORMAL WITH READINGS FROM
THE LOWER 30S IN THE MOUNTAINS TO THE LOWER 40S IN THE PIEDMONT.
COLD FRONT APPROACHES FROM THE WEST WEDNESDAY NIGHT. ALLOWED FOR
ISOLATED SNOW SHOWERS ACROSS THE NORTH. LOW TEMPERATURES WEDNESDAY
NIGHT WILL GENERALLY BE FROM AROUND 20 DEGREES TO THE MID 20S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 400 PM EST SUNDAY...
SURGE OF ARCTIC AIR TO INVADE THE REGION INTO THURSDAY. THIS WAS NOT
ADVERTISED A FEW RUNS BACK...BUT GIVEN GENERAL CONSENSUS AMONG THE
MODELS AND A PREVAILING MEAN DEEP MERIDIONAL TROUGH ACROSS THE
EASTERN HALF OF THE U.S...THIS APPEARS TO BE A REASONABLE SOLUTION
AND THUS WILL LEAN IN THIS DIRECTION. HOWEVER...IN TERMS OF
INTENSITY...THIS FINAL ARCTIC SURGE WILL NOT EVEN COME CLOSE TO THE
ONE EARLIER IN THE WEEK. MOISTURE IS LIMITED...BUT SLIGHT CHC TO LOW
CHC POPS FOR UPSLOPE -SHSN ACROSS THE USUAL WESTERN UPSLOPE AREAS OF
THE ALLEGHANYS SEEMS REASONABLE AND HAVE BEEN INCLUDED...WITH NO
MENTION OF POPS EAST OF THE ALLEGHANY FRONT. THE PARENT ARCTIC HIGH
WILL SETTLE OVER THE REGION EARLY SATURDAY...SO BELOW NORMAL
TEMPERATURES SHOULD REMAIN IN PLACE THROUGH SAT MORNING. MODEL TEMPS
IN REASONABLE AGREEMENT THROUGH FRI...BUT FEEL THE GFS MOS IS TOO
QUICK TO SPREAD WARMER RETURN FLOW INTO THE REGION SAT...SO LEANED
TOWARD THE COLDER ECMWF MOS.
BIGGER QUESTIONS REMAIN FOR THE REMAINDER OF THE EXTENDED PERIODS.
AS THE ARCTIC HIGH RETREATS TOWARD THE COAST SAT...THE LONG
AWAITED RETURN TO A LESS AMPLIFIED FLOW PATTERN BEGINS TO EVOLVE.
THE EASTERN U.S. TROUGH IS REPLACED BY A SHORT WAVE RIDGE AS BROAD
MEAN TROUGHING RELOCATES TO THE WESTERN/CENTRAL U.S. THE MAIN
CONCERN FOR THE WEEKEND IS THE TIMING AND ASSOCIATED
WARMING/MOISTENING WITH A STRONG NEGATIVELY TITLED HIGHLY
PROGRESSIVE SHORT WAVE PROGGED TO EJECT OUT OF THE BASE OF THE
MEAN TROUGH INTO THE SOUTHEAST STATES SAT NIGHT-SUN. 12Z ECMWF IN
EXCELLENT AGREEMENT WITH 12Z GFS IN BRINGING THIS SYSTEM THROUGH
OUR REGION SUN AFTERNOON. SUPERBLEND POPS WERE LIKELY TO
CATEGORICAL SUN NIGHT-MON. GIVEN THE ASSOCIATED PVA...AND AMOUNT
OF MOIST/WARM ADVECTION INTO THE REGION...THIS SEEMED REASONABLE.
HOWEVER...NEIGHBORING OFFICES WERE NOT ON BOARD WITH THESE HIGH
VALUES THIS FAR OUT...SO STOPPED AT A MORE REASONABLE 50 PERCENT
VALUE FOR NOW. GIVEN RECENT MODEL RUN-TO-RUN VARIATION...THAT
SEEMED REASONABLE FOR SURE. A SIGNIFICANT WARM UP WILL ENSUE SAT-
SUN...BUT AS NOTED ABOVE...PERHAPS NOT TO THE DEGREE ADVERTISED BY
THE MEX MOS. THUS...HAVE USED A MODEL BLEND FOR SAT- SUN.
AN EVEN MORE SIGNIFICANT NEGATIVELY TILTED UPPER TROUGH APPEARS ON
TRACK FOR THE REGION INTO MON. ECMWF/GFS SHOWING SOME INCREDIBLY
WARM/MOIST AIR FOR THIS TIME OF YEAR SPREADING INTO THE REGION
FROM THE SOUTH BY MON MORNING ON THE HEELS A STRONG LOW-LEVEL SOUTHERLY
JET WITH DEWPOINTS APPROACHING 60 DEGREES BY MON AFTERNOON ACROSS
THE PIEDMONT AND SOUTHSIDE. PROGGED LIFTED INDICES AND CAPES ALONG
WITH EVIDENT SHEAR SUGGEST SOME -TSRA MAY NEED TO BE CONSIDERED BY
MON AFTERNOON ACROSS THE PIEDMONT. TO SAY THE LEAST...EARLY NEXT
WEEK WILL BE IN SHARP CONTRAST TO THE WEATHER EXPECTED THIS WEEK
WITH TEMPERATURES ACTUALLY ABOVE SEASONAL NORMALS...ESPECIALLY IF
LOWS ARE ONLY IN THE 50S MON MORNING WITH HIGHS IN THE 60S.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
AS OF 1150 PM EST SUNDAY...
ANOTHER LARGE AREA OF LIGHT TO MODERATE RAIN WILL CROSS THE
REGION BETWEEN 08Z/3AM AND 15Z/10AM BASED ON THE LATEST HRRR AND
LOCAL WRF MODELS. HIGH CONFIDENCE THAT CEILINGS WILL DROP TO IFR
AS THIS RAIN MOVES IN. VISIBILITIES WILL LOWER TO MVFR WITH THE RAIN.
SLEET...WHICH IS REPORTED AS U P...UNKNOWN PRECIPITATION...BY AWOS
AND ASOS SENSORS IS FALLING AT KLWB. HOWEVER...WARMER AIR IS
GRADUALLY ADVECTING INTO THE REGION. LITTLE DROP IN TEMPERATURE IS
EXPECTED FOR THE REST OF THE NIGHT. THE SLEET AT KLWB WILL END BY
MIDNIGHT WITH LITTLE TO NO ACCUMULATIONS.
LOW PRESSURE OVER LOUISIANA WILL MOVE INTO THE OHIO VALLEY BY
MORNING THEN WILL PUSH A STRONG COLD FRONT THROUGH THE REGION.
WITH THE ARRIVAL OF THE STRONG COLD FRONT AND DOWNSLOPING WINDS
CONDITIONS RETURN BACK TO VFR EAST OF THE BLUE RIDGE ON MONDAY
AFTERNOON AS RAIN ENDS FROM THE WEST. BUT STRONG COLD ADVECTION
AND UPSLOPE CLOUDS EXPECTED TO PERSIST WEST OF THE BLUE RIDGE WITH
A PROLONGED PERIOD OF MVFR TO OCCASIONALLY IFR WEATHER IN
SCATTERED SNOW SHOWERS LATER MONDAY AFTERNOON.
A STRONG LOW LEVEL JET OF 50-70 KNOTS DEVELOPS OVER THE AREA TOWARD
DAYBREAK. HAVE ADDED LOW LEVEL WIND SHEAR IN FOR THE TAFS. WIND
GUSTS WILL INCREASE FROM THE NORTHWEST BEHIND THE FRONT UP 30 KNOTS
BY EVENING.
EXTENDED DISCUSSION...
EXPECT MAINLY VFR WEATHER EAST OF THE BLUE RIDGE IN THE
TUESDAY-FRIDAY. CONDITIONS WILL BECOME VFR WEST OF THE BLUE RIDGE
UNDER SURFACE HIGH PRESSURE WEDNESDAY...BUT ANOTHER PERIOD OF
UPSLOPING CLOUDS WILL BRING MVFR CONDITIONS THURSDAY AFTERNOON
INTO FRIDAY AS NEXT COLD FRONT MOVES THROUGH THE AREA.
&&
.CLIMATE...
AS OF 315 PM EST SUNDAY...
RECORD COOLEST HIGHS...TUESDAY NOV 18TH
BLACKSBURG VA...30 IN 2008
BLUEFIELD WV....27 IN 2008
DANVILLE VA.....38 IN 1959
ROANOKE VA......33 IN 1951
LEWISBURG WV....30 IN 2008
LYNCHBURG VA....32 IN 1924
&&
.EQUIPMENT...
AS OF 120 AM EST MONDAY...
KFCX RADAR DOWN DUE TO TRANSMITTER FAULT. TECHNICIANS WILL WORK ON
RESTORING THIS BY NOON TODAY.
THE VISIBILITY SENSOR AT KLYH...LYNCHBURG AIRPORT...WILL BE OUT
OF SERVICE UNTIL MONDAY WHEN TECHNICIANS WILL REPLACE THE SENSOR.
UNTIL THEN THE VISIBILITY WILL ONLY BE REPORTED WHEN THE CONTROL
TOWER IS STAFFED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EST
TUESDAY FOR VAZ015.
NC...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EST
TUESDAY FOR NCZ001-018.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...WP
SHORT TERM...KK
LONG TERM...RAB
AVIATION...AMS/WERT
CLIMATE...RCS
EQUIPMENT...WERT/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
128 AM EST MON NOV 17 2014
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL MOVE THROUGH VIRGINIA AND ADJACENT
STATES ON MONDAY MORNING. A STRONG COLD FRONT WILL THEN SWEEP
EAST THOUGH THE AREA ON MONDAY AFTERNOON...BRINGING ANOTHER ROUND
OF VERY COLD TEMPERATURES WITH GUSTY WINDS FOR MONDAY NIGHT INTO
TUESDAY...ALONG WITH SOME MOUNTAIN SNOW SHOWERS.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 120 AM EST MONDAY...
RADAR BEFORE GOING DOWN SHOWED LIMITED COVERAGE OF RAIN IN THE
CWA...WITH NARROW AXIS FROM THE NC FOOTHILLS INTO THE VA PIEDMONT.
THE LATEST HRRR WAS HANDLING THIS FAIRLY WELL...AND THINK OVERALL
A LIGHT RAIN/DRIZZLE OR NO PRECIP WILL BE THE RULE THROUGH DAWN
OVER THE EASTERN 2/3 OF THE CWA. LARGER SHIELD OF RAIN FROM SCNTL
KY SOUTH INTO THE NRN AL/GA SPREADING NE TO MOVE INTO THE WEST BY
4AM...REACHING THE PIEDMONT AROUND 8 AM. 00Z RNK SOUNDING SHOWED
DEEP INVERSION THE LOW LVLS WHICH WITH STRONG LLJ SHOULD KEEP
WINDS ABOVE MOST LOCATIONS FROM MIXING DOWN. STILL HIGHER TERRAIN
OF THE MTN EMPIRE INTO THE NC/TN BORDER AREA COULD SEE SOME GUSTS
OVER 40 MPH BY DAWN. MINOR ADJUSTMENTS MADE TO TEMPS PER LATEST
OBS. LIMITED TEMPS NEAR FREEZING IN THE BATH COUNTY AREA SHOULD
WARM AS MODERATE RAIN SHIELD MOVES IN LATER THIS MORNING. NOT
EXPECTING ANY FROZEN/FREEZING PRECIP ISSUES THERE.
PREVIOUS VALID DISCUSSION...
ALL OF THE INGREDIENTS ARE IN PLACE FOR A WIDESPREAD RAINFALL EVENT
INTO MONDAY MORNING AS LOW PRESSURE LIFTS NORTHEAST OUT OF THE
GULF COAST STATES...THROUGH THE OHIO VALLEY AND MID APPALACHIAN
REGION ON MONDAY MORNING...AND INTO NEW ENGLAND LATER MONDAY
AFTERNOON INTO MONDAY NIGHT.
INCREASING AND DEEPENING AREA OF ISENTROPIC LIFT IN 850-600 MILLIBAR
LAYER WILL COMBINE WITH APPROACH OF RIGHT ENTRANCE REGION OF UPPER
JET AND DIFFERENTIAL POSITIVE VORTICITY ADVECTION IN ADVANCE OF
STRONG UPSTREAM SHORT WAVE TO RESULT IN BROAD UPWARD VERTICAL
MOTIONS FIELDS THROUGH INCREASINGLY SATURATED MID AND LOWER
TROPOSPHERE.
BEST AREA OF FORCING...UPWARD VERTICAL MOTION FIELDS...AND DEEPER
MOISTURE EXPECTED TO RAPIDLY TRANSLATE NORTHEAST OF THE AREA LATE
MONDAY MORNING/EARLY AFTERNOON AS SURFACE LOW PRESSURE REFLECTION
RIDES UP ALONG STRONG COLD FRONT WHICH THEN SWEEPS EAST OF THE
PIEDMONT COUNTIES BY LATER AFTERNOON. STRATIFORM RAIN EXPECTED TO
BE REPLACED BY SHOWERY UPSLOPING SNOW SHOWERS WITH ONSET OF VERY
STRONG COLD ADVECTION AND PLUMMETING TEMPERATURES IN THE MOUNTAINS
AS THE AFTERNOON PROGRESSES. EAST OF THE BLUE RIDGE...ONSET OF
DOWNSLOPING WINDS SHOULD RESULT IN RAPID END OF RAIN FROM WEST TO
EAST BEFORE NIGHTFALL IN MOST AREAS...TO BE FOLLOWED BY GRADUALLY
CLEARING SKIES.
POST-FRONTAL WINDS COULD BECOME STRONG ENOUGH MONDAY AFTERNOON TO
WARRANT ADVISORY LEVEL CONSIDERATION...BUT CURRENT INDICATIONS ARE
THAT WINDS WILL REMAIN JUST BELOW HEADLINE LEVELS AT THE PRESENT
TIME...SO WILL NOT YET BE POSTED. REGARDLESS...MODERATE GUSTY WINDS
AND FALLING TEMPERATURES WILL LIKELY DRIVE DOWN WIND CHILLS INTO THE
TEENS BY LATE IN THE DAY...AND SOME PREFERRED UPSLOPE AREAS MAY
EXPERIENCE AN INCH OR SO OF SNOW BY NIGHTFALL...ESPECIALLY IN
WESTERN GREENBRIER COUNTY.
AS WOULD BE EXPECTED...NON-DIURNAL TEMPERATURE TRENDS WILL POSE A
SIGNIFICANT FORECAST CHALLENGE THROUGH THE NEAR-TERM
PERIOD...ESPECIALLY OVER THE SOUTHEASTERN COUNTIES WHICH COULD
EXPERIENCE A TEMPERATURE BUST ON MONDAY IF THE COOL WEDGE ERODES
PRIOR TO THE ARRIVAL OF THE STRONG COLD FRONT...AND ACROSS THE
WESTERN MOUNTAINS...WHERE TIMING FOR THE ARRIVAL OF THE STRONG
COLD FRONT MAY ALSO RESULT IN A FORECAST BUST. TEMPERATURES WILL
BE WARMER THAN CURRENTLY FORECAST WITH A LATE FRONTAL ARRIVAL IN
THE SOUTHEAST...AND WILL BE COLDER THAN CURRENTLY FORECAST IF THE
FRONT CAN SNEAK INTO THE WESTERN COUNTIES AN HOUR OR TWO EARLIER
THAN CURRENTLY PROJECTED.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
AS OF 315 PM EST SUNDAY...
THE PARENT SURFACE LOW WHICH WILL BRING RAIN TO THE AREA MONDAY WILL
TRACK TO NEW ENGLAND BY MONDAY EVENING. THE FRONT ASSOCIATED WITH
THIS SYSTEM WILL BE ALONG THE EASTERN SHORE WITH A POTENT ARCTIC
AIRMASS SPILLING INTO THE REGION INTO TUESDAY NIGHT. PRESSURE RISES
IMMEDIATELY BEHIND THE FRONT AND A TIGHT PRESSURE GRADIENT WILL
REMAIN OVER THE REGION THROUGH THE DAY TUESDAY. WINDY/GUSTY
CONDITIONS WILL MAKE FOR A BLUSTERY 24-36 HOUR PERIOD STARTING
MONDAY NIGHT. TEMPERATURES MONDAY NIGHT WILL DROP INTO THE 10F-20F
RANGE ACROSS THE MOUNTAINS WITH EARLY TUESDAY MORNING WIND CHILLS
RANGING FROM BELOW ZERO IN THE HIGHER ELEVATIONS TO ABOVE ZERO
SINGLE DIGITS IN MOUNTAIN VALLEYS. NOT MUCH OF A WARM-UP TUESDAY AS
THE MOUNTAINS WILL NOT MAKE THE FREEZING MARK. VERY COLD
TEMPERATURES FOR MID NOVEMBER ALSO EXPECTED IN THE EAST...ACROSS THE
FOOTHILLS AND PIEDMONT COUNTIES. MONDAY NIGHT TEMPERATURES WILL BE
IN THE 20S WITH TUESDAY MORNING WIND CHILLS IN THE MID TEENS TO
LOWER 20S. AS THE WIND RELAXES TUESDAY AFTERNOON...THE EAST WILL
WARM INTO THE 30S.
TUESDAY NIGHT WILL ALSO BE A VERY COLD NIGHT WITH TEMPERATURES
ACROSS THE AREA RANGING FROM THE SINGLE DIGITS IN THE HIGHER
ELEVATIONS TO THE UPPER TEENS ACROSS THE PIEDMONT. WINDS WILL BE
LESS OF AN ISSUE TUESDAY NIGHT BUT WIND CHILLS WILL AGAIN BE COLD
WITH SINGLE DIGITS IN THE WEST TO TEENS IN THE EAST. A WARM FRONT
WILL PASS OVER THE REGION WEDNESDAY. TEMPERATURES WILL MODERATE INTO
THE 30S WEST TO 40S EAST. DESPITE THE MILD TEMPERATURES ENTER THE
REGION WEDNESDAY...AFTERNOON HIGHS WILL STILL RUN 20F COLDER THAN
NORMAL.
ACCUMULATING SNOW IS LIKELY FOR WESTERN SLOPES MONDAY NIGHT INTO
TUESDAY. TRAJECTORIES FROM THE GREAT LAKES IS NOT IDEAL. WESTERN
GREENBRIER COULD SEE 2-3 INCHES OF SNOW BY TUESDAY EVENING...1-2
INCHES AROUND BLUEFIELD. OUTSIDE OF WESTERN SLOPES...A DUSTING TO A
HALF OF AN INCH IF SNOW BANDS FORM. MORE THAN NOT...24-36 HOURS OF
MOUNTAIN FLURRIES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 400 PM EST SUNDAY...
MANY CHANGES TO CONSIDER THROUGH THE LONG TERM PERIODS.
FIRST...MOST OF THE MODELS HAVE COME INTO AGREEMENT IN SHOWING YET
ANOTHER SURGE OF ARCTIC AIR TO INVADE THE REGION WED NIGHT INTO
THURSDAY. THIS WAS NOT ADVERTISED A FEW RUNS BACK...BUT GIVEN
GENERAL CONSENSUS AMONG THE MODELS AND A PREVAILING MEAN DEEP
MERIDIONAL TROUGH ACROSS THE EASTERN HALF OF THE U.S...THIS
APPEARS TO BE A REASONABLE SOLUTION AND THUS WILL LEAN IN THIS
DIRECTION. HOWEVER...IN TERMS OF INTENSITY...THIS FINAL ARCTIC
SURGE WILL NOT EVEN COME CLOSE TO THE ONE EARLIER IN THE WEEK.
MOISTURE IS LIMITED...BUT SLIGHT CHC TO LOW CHC POPS FOR UPSLOPE
-SHSN ACROSS THE USUAL WESTERN UPSLOPE AREAS OF THE ALLEGHANYS
SEEMS REASONABLE AND HAVE BEEN INCLUDED...WITH NO MENTION OF POPS
EAST OF THE ALLEGHANY FRONT. THE PARENT ARCTIC HIGH WILL SETTLE
OVER THE REGION EARLY SATURDAY...SO BELOW NORMAL TEMPERATURES
SHOULD REMAIN IN PLACE THROUGH SAT MORNING. MODEL TEMPS IN
REASONABLE AGREEMENT THROUGH FRI...BUT FEEL THE GFS MOS IS TOO
QUICK TO SPREAD WARMER RETURN FLOW INTO THE REGION SAT...SO LEANED
TOWARD THE COLDER ECMWF MOS.
BIGGER QUESTIONS REMAIN FOR THE REMAINDER OF THE EXTENDED PERIODS.
AS THE ARCTIC HIGH RETREATS TOWARD THE COAST SAT...THE LONG
AWAITED RETURN TO A LESS AMPLIFIED FLOW PATTERN BEGINS TO EVOLVE.
THE EASTERN U.S. TROUGH IS REPLACED BY A SHORT WAVE RIDGE AS BROAD
MEAN TROUGHING RELOCATES TO THE WESTERN/CENTRAL U.S. THE MAIN
CONCERN FOR THE WEEKEND IS THE TIMING AND ASSOCIATED
WARMING/MOISTENING WITH A STRONG NEGATIVELY TITLED HIGHLY
PROGRESSIVE SHORT WAVE PROGGED TO EJECT OUT OF THE BASE OF THE
MEAN TROUGH INTO THE SOUTHEAST STATES SAT NIGHT-SUN. 12Z ECMWF IN
EXCELLENT AGREEMENT WITH 12Z GFS IN BRINGING THIS SYSTEM THROUGH
OUR REGION SUN AFTERNOON. SUPERBLEND POPS WERE LIKELY TO
CATEGORICAL SUN NIGHT-MON. GIVEN THE ASSOCIATED PVA...AND AMOUNT
OF MOIST/WARM ADVECTION INTO THE REGION...THIS SEEMED REASONABLE.
HOWEVER...NEIGHBORING OFFICES WERE NOT ON BOARD WITH THESE HIGH
VALUES THIS FAR OUT...SO STOPPED AT A MORE REASONABLE 50 PERCENT
VALUE FOR NOW. GIVEN RECENT MODEL RUN-TO-RUN VARIATION...THAT
SEEMED REASONABLE FOR SURE. A SIGNIFICANT WARM UP WILL ENSUE SAT-
SUN...BUT AS NOTED ABOVE...PERHAPS NOT TO THE DEGREE ADVERTISED BY
THE MEX MOS. THUS...HAVE USED A MODEL BLEND FOR SAT- SUN.
AN EVEN MORE SIGNIFICANT NEGATIVELY TILTED UPPER TROUGH APPEARS ON
TRACK FOR THE REGION INTO MON. ECMWF/GFS SHOWING SOME INCREDIBLY
WARM/MOIST AIR FOR THIS TIME OF YEAR SPREADING INTO THE REGION
FROM THE SOUTH BY MON MORNING ON THE HEELS A STRONG LOW-LEVEL SOUTHERLY
JET WITH DEWPOINTS APPROACHING 60 DEGREES BY MON AFTERNOON ACROSS
THE PIEDMONT AND SOUTHSIDE. PROGGED LIFTED INDICES AND CAPES ALONG
WITH EVIDENT SHEAR SUGGEST SOME -TSRA MAY NEED TO BE CONSIDERED BY
MON AFTERNOON ACROSS THE PIEDMONT. TO SAY THE LEAST...EARLY NEXT
WEEK WILL BE IN SHARP CONTRAST TO THE WEATHER EXPECTED THIS WEEK
WITH TEMPERATURES ACTUALLY ABOVE SEASONAL NORMALS...ESPECIALLY IF
LOWS ARE ONLY IN THE 50S MON MORNING WITH HIGHS IN THE 60S.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 1150 PM EST SUNDAY...
ANOTHER LARGE AREA OF LIGHT TO MODERATE RAIN WILL CROSS THE
REGION BETWEEN 08Z/3AM AND 15Z/10AM BASED ON THE LATEST HRRR AND
LOCAL WRF MODELS. HIGH CONFIDENCE THAT CEILINGS WILL DROP TO IFR
AS THIS RAIN MOVES IN. VISIBILITIES WILL LOWER TO MVFR WITH THE RAIN.
SLEET...WHICH IS REPORTED AS U P...UNKNOWN PRECIPITATION...BY AWOS
AND ASOS SENSORS IS FALLING AT KLWB. HOWEVER...WARMER AIR IS
GRADUALLY ADVECTING INTO THE REGION. LITTLE DROP IN TEMPERATURE IS
EXPECTED FOR THE REST OF THE NIGHT. THE SLEET AT KLWB WILL END BY
MIDNIGHT WITH LITTLE TO NO ACCUMULATIONS.
LOW PRESSURE OVER LOUISIANA WILL MOVE INTO THE OHIO VALLEY BY
MORNING THEN WILL PUSH A STRONG COLD FRONT THROUGH THE REGION.
WITH THE ARRIVAL OF THE STRONG COLD FRONT AND DOWNSLOPING WINDS
CONDITIONS RETURN BACK TO VFR EAST OF THE BLUE RIDGE ON MONDAY
AFTERNOON AS RAIN ENDS FROM THE WEST. BUT STRONG COLD ADVECTION
AND UPSLOPE CLOUDS EXPECTED TO PERSIST WEST OF THE BLUE RIDGE WITH
A PROLONGED PERIOD OF MVFR TO OCCASIONALLY IFR WEATHER IN
SCATTERED SNOW SHOWERS LATER MONDAY AFTERNOON.
A STRONG LOW LEVEL JET OF 50-70 KNOTS DEVELOPS OVER THE AREA TOWARD
DAYBREAK. HAVE ADDED LOW LEVEL WIND SHEAR IN FOR THE TAFS. WIND
GUSTS WILL INCREASE FROM THE NORTHWEST BEHIND THE FRONT UP 30 KNOTS
BY EVENING.
EXTENDED DISCUSSION...
EXPECT MAINLY VFR WEATHER EAST OF THE BLUE RIDGE IN THE
TUESDAY-FRIDAY. CONDITIONS WILL BECOME VFR WEST OF THE BLUE RIDGE
UNDER SURFACE HIGH PRESSURE WEDNESDAY...BUT ANOTHER PERIOD OF
UPSLOPING CLOUDS WILL BRING MVFR CONDITIONS THURSDAY AFTERNOON
INTO FRIDAY AS NEXT COLD FRONT MOVES THROUGH THE AREA.
&&
.HYDROLOGY...
AS OF 105 PM EST SUNDAY...
FORECAST PRECIPITATION FOR THE UPCOMING EVENT STILL EXPECTED TO
RANGE FROM ABOUT ONE-HALF /0.50/ INCH OVER THE NORTHERN RIVER
BASINS UP TO ABOUT ONE /1.25/ INCHES OVER THE SOUTHERN RIVER
BASINS BY THE TIME IT ENDS LATE MONDAY.
THE RAINFALL IS NEEDED AS PRECIPITATION IN NOVEMBER TO DATE HAS
BEEN VERY SCANTY. MOST OF THE COOP NETWORK SITES HAVE RECEIVED
UNDER 0.50 INCHES FOR THE MONTH...AND SOME LESS THAN 0.25 INCHES.
A SUBSTANTIAL PORTION OF THE PIEDMONT IN OUR HYDROLOGIC SERVICE
AREA IS ALREADY IN THE ABNORMALLY DRY CATEGORY ON THE WEEKLY U.S.
DROUGHT MONITOR...WITH RAINFALL DEFICITS OF 2 TO 4 INCHES OVER
THE PAST 60 DAYS.
THE DRY PERIOD IS REFLECTED IN DECLINING STREAM FLOWS AS
MONITORED BY THE USGS STREAM GAGING NETWORK AND ALSO BY FALLING
RESERVOIR STORAGE.
&&
.CLIMATE...
AS OF 315 PM EST SUNDAY...
RECORD COOLEST HIGHS...TUESDAY NOV 18TH
BLACKSBURG VA...30 IN 2008
BLUEFIELD WV....27 IN 2008
DANVILLE VA.....38 IN 1959
ROANOKE VA......33 IN 1951
LEWISBURG WV....30 IN 2008
LYNCHBURG VA....32 IN 1924
&&
.EQUIPMENT...
AS OF 120 AM EST MONDAY...
KFCX RADAR DOWN DUE TO TRANSMITTER FAULT. TECHNICIANS WILL WORK ON
RESTORING THIS BY NOON TODAY.
THE VISIBILITY SENSOR AT KLYH...LYNCHBURG AIRPORT...WILL BE OUT
OF SERVICE UNTIL MONDAY WHEN TECHNICIANS WILL REPLACE THE SENSOR.
UNTIL THEN THE VISIBILITY WILL ONLY BE REPORTED WHEN THE CONTROL
TOWER IS STAFFED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...WERT/WP
SHORT TERM...RCS
LONG TERM...RAB
AVIATION...AMS/WERT
HYDROLOGY...PC/WERT/WP
CLIMATE...RCS
EQUIPMENT...WERT/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1151 PM EST SUN NOV 16 2014
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL LIFT NORTHEAST OUT OF THE GULF COAST
STATES TONIGHT...AND MOVE THROUGH VIRGINIA AND ADJACENT STATES ON
MONDAY MORNING. THIS SYSTEM WILL BE PRECEDED AND ACCOMPANIED BY
WIDESPREAD LIGHT TO MODERATE RAIN. A STRONG COLD FRONT WILL THEN
SWEEP EAST THOUGH THE AREA ON MONDAY AFTERNOON...BRINGING ANOTHER
ROUND OF VERY COLD TEMPERATURES WITH GUSTY WINDS FOR MONDAY NIGHT
INTO TUESDAY...ALONG WITH SOME MOUNTAIN SNOW SHOWERS.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 315 PM EST SUNDAY...
ALL OF THE INGREDIENTS ARE IN PLACE FOR A WIDESPREAD RAINFALL EVENT
TONIGHT INTO MONDAY MORNING AS LOW PRESSURE LIFTS NORTHEAST OUT OF
THE GULF COAST STATES...THROUGH THE OHIO VALLEY AND MID APPALACHIAN
REGION ON MONDAY MORNING...AND INTO NEW ENGLAND LATER MONDAY
AFTERNOON INTO MONDAY NIGHT.
INCREASING AND DEEPENING AREA OF ISENTROPIC LIFT IN 850-600 MILLIBAR
LAYER WILL COMBINE WITH APPROACH OF RIGHT ENTRANCE REGION OF UPPER
JET AND DIFFERENTIAL POSITIVE VORTICITY ADVECTION IN ADVANCE OF
STRONG UPSTREAM SHORT WAVE TO RESULT IN BROAD UPWARD VERTICAL
MOTIONS FIELDS THROUGH INCREASINGLY SATURATED MID AND LOWER
TROPOSPHERE.
LIGHT RAIN IN ADVANCE OF THE SYSTEM HAS ALREADY BEGUN...OR WAS IN
THE PROCESS OF BEGINNING FROM THE NW NC MOUNTAINS NORTH THROUGH
PORTIONS OF THE NEW RIVER VALLEY INTO THE ALLEGHANY HIGHLANDS OF
VA...WEST INTO THE SE WV COUNTIES. PRECIPITATION IS EXPECTED TO
CONTINUE TO OVERSPREAD THE PIEDMONT COUNTIES BY/DURING THE EARLY-
MID EVENING HOURS.
ONSET OF PRECIPITATION IS WET-BULBING TEMPERATURES BACK DOWN INTO
THE 30S IN THE MOUNTAINS...AND WILL DRIVE TEMPERATURES BACK DOWN
TO AROUND 40F ACROSS THE PIEDMONT WHEN IT BEGINS...WITH
TEMPERATURES THEN LIKELY TO FLATLINE FOR THE REST OF THE NIGHT AS
WARM ADVECTION CONTINUES AND INCREASES OVER INVERSION LAYER. A
BRIEF PERIOD OF SLEET IS EVEN POSSIBLE AT THE ONSET OF THE
EVENT...ESPECIALLY IN AREAS NORTH OF INTERSTATE 64...BUT NO
ACCUMULATIONS ARE EXPECTED CONSIDERING TEMPERATURES ARE EXPECTED
TO REMAIN ABOVE FREEZING DESPITE WET-BULB INFLUENCES.
STRENGTH OF INVERSION LIKELY TO BE OF SUFFICIENT DEPTH TO
LIMIT/HINDER WINDS UNDER DEVELOPING LOW LEVEL JET OF 40-50 KNOTS
LATER TONIGHT INTO MONDAY MORNING FROM PENETRATING DOWN TO
SURFACE...EVEN ACROSS THE HIGHER TERRAIN.
BEST AREA OF FORCING...UPWARD VERTICAL MOTION FIELDS...AND DEEPER
MOISTURE EXPECTED TO RAPIDLY TRANSLATE NORTHEAST OF THE AREA LATE
MONDAY MORNING/EARLY AFTERNOON AS SURFACE LOW PRESSURE REFLECTION
RIDES UP ALONG STRONG COLD FRONT WHICH THEN SWEEPS EAST OF THE
PIEDMONT COUNTIES BY LATER AFTERNOON. STRATIFORM RAIN EXPECTED TO
BE REPLACED BY SHOWERY UPSLOPING SNOW SHOWERS WITH ONSET OF VERY
STRONG COLD ADVECTION AND PLUMMETING TEMPERATURES IN THE MOUNTAINS
AS THE AFTERNOON PROGRESSES. EAST OF THE BLUE RIDGE...ONSET OF
DOWNSLOPING WINDS SHOULD RESULT IN RAPID END OF RAIN FROM WEST TO
EAST BEFORE NIGHTFALL IN MOST AREAS...TO BE FOLLOWED BY GRADUALLY
CLEARING SKIES.
POST-FRONTAL WINDS COULD BECOME STRONG ENOUGH MONDAY AFTERNOON TO
WARRANT ADVISORY LEVEL CONSIDERATION...BUT CURRENT INDICATIONS ARE
THAT WINDS WILL REMAIN JUST BELOW HEADLINE LEVELS AT THE PRESENT
TIME...SO WILL NOT YET BE POSTED. REGARDLESS...MODERATE GUSTY WINDS
AND FALLING TEMPERATURES WILL LIKELY DRIVE DOWN WIND CHILLS INTO THE
TEENS BY LATE IN THE DAY...AND SOME PREFERRED UPSLOPE AREAS MAY
EXPERIENCE AN INCH OR SO OF SNOW BY NIGHTFALL...ESPECIALLY IN
WESTERN GREENBRIER COUNTY.
AS WOULD BE EXPECTED...NON-DIURNAL TEMPERATURE TRENDS WILL POSE A
SIGNIFICANT FORECAST CHALLENGE THROUGH THE NEAR-TERM
PERIOD...ESPECIALLY OVER THE SOUTHEASTERN COUNTIES WHICH COULD
EXPERIENCE A TEMPERATURE BUST ON MONDAY IF THE COOL WEDGE ERODES
PRIOR TO THE ARRIVAL OF THE STRONG COLD FRONT...AND ACROSS THE
WESTERN MOUNTAINS...WHERE TIMING FOR THE ARRIVAL OF THE STRONG
COLD FRONT MAY ALSO RESULT IN A FORECAST BUST. TEMPERATURES WILL
BE WARMER THAN CURRENTLY FORECAST WITH A LATE FRONTAL ARRIVAL IN
THE SOUTHEAST...AND WILL BE COLDER THAN CURRENTLY FORECAST IF THE
FRONT CAN SNEAK INTO THE WESTERN COUNTIES AN HOUR OR TWO EARLIER
THAN CURRENTLY PROJECTED.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 315 PM EST SUNDAY...
THE PARENT SURFACE LOW WHICH WILL BRING RAIN TO THE AREA MONDAY WILL
TRACK TO NEW ENGLAND BY MONDAY EVENING. THE FRONT ASSOCIATED WITH
THIS SYSTEM WILL BE ALONG THE EASTERN SHORE WITH A POTENT ARCTIC
AIRMASS SPILLING INTO THE REGION INTO TUESDAY NIGHT. PRESSURE RISES
IMMEDIATELY BEHIND THE FRONT AND A TIGHT PRESSURE GRADIENT WILL
REMAIN OVER THE REGION THROUGH THE DAY TUESDAY. WINDY/GUSTY
CONDITIONS WILL MAKE FOR A BLUSTERY 24-36 HOUR PERIOD STARTING
MONDAY NIGHT. TEMPERATURES MONDAY NIGHT WILL DROP INTO THE 10F-20F
RANGE ACROSS THE MOUNTAINS WITH EARLY TUESDAY MORNING WIND CHILLS
RANGING FROM BELOW ZERO IN THE HIGHER ELEVATIONS TO ABOVE ZERO
SINGLE DIGITS IN MOUNTAIN VALLEYS. NOT MUCH OF A WARM-UP TUESDAY AS
THE MOUNTAINS WILL NOT MAKE THE FREEZING MARK. VERY COLD
TEMPERATURES FOR MID NOVEMBER ALSO EXPECTED IN THE EAST...ACROSS THE
FOOTHILLS AND PIEDMONT COUNTIES. MONDAY NIGHT TEMPERATURES WILL BE
IN THE 20S WITH TUESDAY MORNING WIND CHILLS IN THE MID TEENS TO
LOWER 20S. AS THE WIND RELAXES TUESDAY AFTERNOON...THE EAST WILL
WARM INTO THE 30S.
TUESDAY NIGHT WILL ALSO BE A VERY COLD NIGHT WITH TEMPERATURES
ACROSS THE AREA RANGING FROM THE SINGLE DIGITS IN THE HIGHER
ELEVATIONS TO THE UPPER TEENS ACROSS THE PIEDMONT. WINDS WILL BE
LESS OF AN ISSUE TUESDAY NIGHT BUT WIND CHILLS WILL AGAIN BE COLD
WITH SINGLE DIGITS IN THE WEST TO TEENS IN THE EAST. A WARM FRONT
WILL PASS OVER THE REGION WEDNESDAY. TEMPERATURES WILL MODERATE INTO
THE 30S WEST TO 40S EAST. DESPITE THE MILD TEMPERATURES ENTER THE
REGION WEDNESDAY...AFTERNOON HIGHS WILL STILL RUN 20F COLDER THAN
NORMAL.
ACCUMULATING SNOW IS LIKELY FOR WESTERN SLOPES MONDAY NIGHT INTO
TUESDAY. TRAJECTORIES FROM THE GREAT LAKES IS NOT IDEAL. WESTERN
GREENBRIER COULD SEE 2-3 INCHES OF SNOW BY TUESDAY EVENING...1-2
INCHES AROUND BLUEFIELD. OUTSIDE OF WESTERN SLOPES...A DUSTING TO A
HALF OF AN INCH IF SNOW BANDS FORM. MORE THAN NOT...24-36 HOURS OF
MOUNTAIN FLURRIES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 400 PM EST SUNDAY...
MANY CHANGES TO CONSIDER THROUGH THE LONG TERM PERIODS.
FIRST...MOST OF THE MODELS HAVE COME INTO AGREEMENT IN SHOWING YET
ANOTHER SURGE OF ARCTIC AIR TO INVADE THE REGION WED NIGHT INTO
THURSDAY. THIS WAS NOT ADVERTISED A FEW RUNS BACK...BUT GIVEN
GENERAL CONSENSUS AMONG THE MODELS AND A PREVAILING MEAN DEEP
MERIDIONAL TROUGH ACROSS THE EASTERN HALF OF THE U.S...THIS
APPEARS TO BE A REASONABLE SOLUTION AND THUS WILL LEAN IN THIS
DIRECTION. HOWEVER...IN TERMS OF INTENSITY...THIS FINAL ARCTIC
SURGE WILL NOT EVEN COME CLOSE TO THE ONE EARLIER IN THE WEEK.
MOISTURE IS LIMITED...BUT SLIGHT CHC TO LOW CHC POPS FOR UPSLOPE
-SHSN ACROSS THE USUAL WESTERN UPSLOPE AREAS OF THE ALLEGHANYS
SEEMS REASONABLE AND HAVE BEEN INCLUDED...WITH NO MENTION OF POPS
EAST OF THE ALLEGHANY FRONT. THE PARENT ARCTIC HIGH WILL SETTLE
OVER THE REGION EARLY SATURDAY...SO BELOW NORMAL TEMPERATURES
SHOULD REMAIN IN PLACE THROUGH SAT MORNING. MODEL TEMPS IN
REASONABLE AGREEMENT THROUGH FRI...BUT FEEL THE GFS MOS IS TOO
QUICK TO SPREAD WARMER RETURN FLOW INTO THE REGION SAT...SO LEANED
TOWARD THE COLDER ECMWF MOS.
BIGGER QUESTIONS REMAIN FOR THE REMAINDER OF THE EXTENDED PERIODS.
AS THE ARCTIC HIGH RETREATS TOWARD THE COAST SAT...THE LONG
AWAITED RETURN TO A LESS AMPLIFIED FLOW PATTERN BEGINS TO EVOLVE.
THE EASTERN U.S. TROUGH IS REPLACED BY A SHORT WAVE RIDGE AS BROAD
MEAN TROUGHING RELOCATES TO THE WESTERN/CENTRAL U.S. THE MAIN
CONCERN FOR THE WEEKEND IS THE TIMING AND ASSOCIATED
WARMING/MOISTENING WITH A STRONG NEGATIVELY TITLED HIGHLY
PROGRESSIVE SHORT WAVE PROGGED TO EJECT OUT OF THE BASE OF THE
MEAN TROUGH INTO THE SOUTHEAST STATES SAT NIGHT-SUN. 12Z ECMWF IN
EXCELLENT AGREEMENT WITH 12Z GFS IN BRINGING THIS SYSTEM THROUGH
OUR REGION SUN AFTERNOON. SUPERBLEND POPS WERE LIKELY TO
CATEGORICAL SUN NIGHT-MON. GIVEN THE ASSOCIATED PVA...AND AMOUNT
OF MOIST/WARM ADVECTION INTO THE REGION...THIS SEEMED REASONABLE.
HOWEVER...NEIGHBORING OFFICES WERE NOT ON BOARD WITH THESE HIGH
VALUES THIS FAR OUT...SO STOPPED AT A MORE REASONABLE 50 PERCENT
VALUE FOR NOW. GIVEN RECENT MODEL RUN-TO-RUN VARIATION...THAT
SEEMED REASONABLE FOR SURE. A SIGNIFICANT WARM UP WILL ENSUE SAT-
SUN...BUT AS NOTED ABOVE...PERHAPS NOT TO THE DEGREE ADVERTISED BY
THE MEX MOS. THUS...HAVE USED A MODEL BLEND FOR SAT- SUN.
AN EVEN MORE SIGNIFICANT NEGATIVELY TILTED UPPER TROUGH APPEARS ON
TRACK FOR THE REGION INTO MON. ECMWF/GFS SHOWING SOME INCREDIBLY
WARM/MOIST AIR FOR THIS TIME OF YEAR SPREADING INTO THE REGION
FROM THE SOUTH BY MON MORNING ON THE HEELS A STRONG LOW-LEVEL SOUTHERLY
JET WITH DEWPOINTS APPROACHING 60 DEGREES BY MON AFTERNOON ACROSS
THE PIEDMONT AND SOUTHSIDE. PROGGED LIFTED INDICES AND CAPES ALONG
WITH EVIDENT SHEAR SUGGEST SOME -TSRA MAY NEED TO BE CONSIDERED BY
MON AFTERNOON ACROSS THE PIEDMONT. TO SAY THE LEAST...EARLY NEXT
WEEK WILL BE IN SHARP CONTRAST TO THE WEATHER EXPECTED THIS WEEK
WITH TEMPERATURES ACTUALLY ABOVE SEASONAL NORMALS...ESPECIALLY IF
LOWS ARE ONLY IN THE 50S MON MORNING WITH HIGHS IN THE 60S.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 1150 PM EST SUNDAY...
ANOTHER LARGE AREA OF LIGHT TO MODERATE RAIN WILL CROSS THE
REGION BETWEEN 08Z/3AM AND 15Z/10AM BASED ON THE LATEST HRRR AND
LOCAL WRF MODELS. HIGH CONFIDENCE THAT CEILINGS WILL DROP TO IFR
AS THIS RAIN MOVES IN. VISIBILITIES WILL LOWER TO MVFR WITH THE RAIN.
SLEET...WHICH IS REPORTED AS U P...UNKNOWN PRECIPITATION...BY AWOS
AND ASOS SENSORS IS FALLING AT KLWB. HOWEVER...WARMER AIR IS
GRADUALLY ADVECTING INTO THE REGION. LITTLE DROP IN TEMPERATURE IS
EXPECTED FOR THE REST OF THE NIGHT. THE SLEET AT KLWB WILL END BY
MIDNIGHT WITH LITTLE TO NO ACCUMULATIONS.
LOW PRESSURE OVER LOUISIANA WILL MOVE INTO THE OHIO VALLEY BY
MORNING THEN WILL PUSH A STRONG COLD FRONT THROUGH THE REGION.
WITH THE ARRIVAL OF THE STRONG COLD FRONT AND DOWNSLOPING WINDS
CONDITIONS RETURN BACK TO VFR EAST OF THE BLUE RIDGE ON MONDAY
AFTERNOON AS RAIN ENDS FROM THE WEST. BUT STRONG COLD ADVECTION
AND UPSLOPE CLOUDS EXPECTED TO PERSIST WEST OF THE BLUE RIDGE WITH
A PROLONGED PERIOD OF MVFR TO OCCASIONALLY IFR WEATHER IN
SCATTERED SNOW SHOWERS LATER MONDAY AFTERNOON.
A STRONG LOW LEVEL JET OF 50-70 KNOTS DEVELOPS OVER THE AREA TOWARD
DAYBREAK. HAVE ADDED LOW LEVEL WIND SHEAR IN FOR THE TAFS. WIND
GUSTS WILL INCREASE FROM THE NORTHWEST BEHIND THE FRONT UP 30 KNOTS
BY EVENING.
EXTENDED DISCUSSION...
EXPECT MAINLY VFR WEATHER EAST OF THE BLUE RIDGE IN THE
TUESDAY-FRIDAY. CONDITIONS WILL BECOME VFR WEST OF THE BLUE RIDGE
UNDER SURFACE HIGH PRESSURE WEDNESDAY...BUT ANOTHER PERIOD OF
UPSLOPING CLOUDS WILL BRING MVFR CONDITIONS THURSDAY AFTERNOON
INTO FRIDAY AS NEXT COLD FRONT MOVES THROUGH THE AREA.
&&
.HYDROLOGY...
AS OF 105 PM EST SUNDAY...
FORECAST PRECIPITATION FOR THE UPCOMING EVENT STILL EXPECTED TO
RANGE FROM ABOUT ONE-HALF /0.50/ INCH OVER THE NORTHERN RIVER
BASINS UP TO ABOUT ONE /1.25/ INCHES OVER THE SOUTHERN RIVER
BASINS BY THE TIME IT ENDS LATE MONDAY.
THE RAINFALL IS NEEDED AS PRECIPITATION IN NOVEMBER TO DATE HAS
BEEN VERY SCANTY. MOST OF THE COOP NETWORK SITES HAVE RECEIVED
UNDER 0.50 INCHES FOR THE MONTH...AND SOME LESS THAN 0.25 INCHES.
A SUBSTANTIAL PORTION OF THE PIEDMONT IN OUR HYDROLOGIC SERVICE
AREA IS ALREADY IN THE ABNORMALLY DRY CATEGORY ON THE WEEKLY U.S.
DROUGHT MONITOR...WITH RAINFALL DEFICITS OF 2 TO 4 INCHES OVER
THE PAST 60 DAYS.
THE DRY PERIOD IS REFLECTED IN DECLINING STREAM FLOWS AS
MONITORED BY THE USGS STREAM GAGING NETWORK AND ALSO BY FALLING
RESERVOIR STORAGE.
&&
.CLIMATE...
AS OF 315 PM EST SUNDAY...
RECORD COOLEST HIGHS...TUESDAY NOV 18TH
BLACKSBURG VA...30 IN 2008
BLUEFIELD WV....27 IN 2008
DANVILLE VA.....38 IN 1959
ROANOKE VA......33 IN 1951
LEWISBURG WV....30 IN 2008
LYNCHBURG VA....32 IN 1924
&&
.EQUIPMENT...
AS OF 650 PM EST SUNDAY...
THE VISIBILITY SENSOR AT KLYH...LYNCHBURG AIRPORT...WILL BE OUT
OF SERVICE UNTIL MONDAY WHEN TECHNICIANS WILL REPLACE THE SENSOR.
UNTIL THEN THE VISIBILITY WILL ONLY BE REPORTED WHEN THE CONTROL
TOWER IS STAFFED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...WERT
SHORT TERM...RCS
LONG TERM...RAB
AVIATION...AMS/WERT
HYDROLOGY...PC/WERT/WP
CLIMATE...RCS
EQUIPMENT...WERT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1134 PM CST SUN NOV 16 2014
.UPDATE...
ISSUED AT 528 PM CST SUN NOV 16 2014
LOSS OF DAYTIME HEATING HAS HELPED TO REALLY CLEAR SKIES OUT BACK
IN THE DAKOTAS AND PARTS OF WESTERN MN. THIS CLEARING AREA LOOKS
POISED TO MOVE INTO THE REGION OVERNIGHT...SO MAY HAVE TO ADJUST
SKY COVER DOWNWARDS. STILL LOOKS LIKE CLOUDS WILL GREATLY INCREASE
IN THE MORNING AS THE SUN DESTABILIZES THE ATMOSPHERE UNDER THE
UNSEASONABLY COLD AIR ALOFT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 158 PM CST SUN NOV 16 2014
PRIMARY CHALLENGES INCLUDE LIGHT SNOW TONIGHT THROUGH MONDAY AND
STRONG NORTHWEST WINDS IN THE WAKE OF AN ARCTIC FRONT THROUGH THE
DAY ON MONDAY. 16.12Z GLOBAL MODELS ARE IN GOOD AGREEMENT THROUGH
19.12Z...DIVERGING SOMEWHAT THEREAFTER IN TIMING AND STRENGTH OF
SHORT-WAVES MOVING THROUGH PARENT NORTHWEST FLOW ALOFT...BECOMING
MORE ZONAL BY NEXT WEEKEND.
16.20Z SURFACE ANALYSIS SHOWS A STRONG ARCTIC/COLD FRONT DRAPED
FROM NEAR ROSEAU MN TO ABERDEEN SD. THIS FEATURE WILL SWEEP
ACROSS THE UPPER MISSISSIPPI RIVER VALLEY OVERNIGHT...BRINGING
WITH IT SCATTERED LIGHT SNOW SHOWERS AMOUNTING TO NO MORE THAN AN
INCH OF ACCUMULATION AND STRONG NORTHWEST WIND IN ITS WAKE.
SURFACE OBS BEHIND THE FRONT THIS AFTERNOON ACROSS ND SHOWING
GUSTS IN EXCESS OF 30 KTS AND ALTHOUGH THIS AIR MASS WILL MODIFY
SOMEWHAT AS IT DROPS SOUTH...16.19Z RAP BRINGS A NOSE OF 35 TO 40
KTS AT 0.5 KM INTO THE WESTERN FORECAST AREA BY MONDAY MORNING.
WITH A DEEPENING WELL-MIXED BOUNDARY LAYER...THIS SHOULD RESULT IN
WIDESPREAD 20 TO 25 MPH NORTHWEST WINDS WITH FREQUENT GUSTS UP TO
35 MPH. THESE WINDS COMBINED WITH 2 TO 4 INCHES OF NEW SNOWFALL
FROM SUNDAY AND SUNDAY NIGHT ACROSS PORTIONS OF SOUTHEAST MN AND
NORTHEAST IA WILL RESULT IN AREAS OF BLOWING AND DRIFTING SNOW...
REDUCING VISIBILITY AT TIMES TO ONE HALF MILE OR LESS. WILL ISSUE
A WINTER WEATHER ADVISORY FOR BLOWING SNOW FROM 17.12Z TO 18.00Z
ACROSS THE WESTERN THIRD OF THE FORECAST AREA. THE COMBINATION OF
POOR VISIBILITY AND BLOWING SNOW WILL CREATE DIFFICULT TRAVEL
CONDITIONS FOR THE MORNING COMMUTE AND CONTINUING THROUGH MUCH OF
THE DAY.
OTHERWISE...MONDAY WILL BE MOSTLY CLOUDY AND COLD WITH AFTERNOON
HIGHS ONLY IN THE TEENS. SCATTERED LIGHT SNOW SHOWERS WILL RESULT
IN MINOR ADDITIONAL ACCUMULATIONS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 158 PM CST SUN NOV 16 2014
850 HPA TEMPERATURES PLUNGE TO -18 C ACROSS THE FORECAST AREA BY
18.12Z (TUESDAY MORNING). THIS WILL RESULT IN THE COLDEST MORNING
SO FAR THIS SEASON. TEMPERATURES WILL FALL INTO THE SINGLE DIGITS
ABOVE ZERO WITH FAVORED COLD SPOTS DROPPING BELOW ZERO. COMBINED
WITH WESTERLY WINDS FROM 10 TO 15 MPH...WIND CHILL VALUES WILL BE
IN THE 10 TO 20 BELOW RANGE. THE REST OF TUESDAY WILL BE DRY AND
SHOULD SEE SOME PEAKS OF SUNSHINE LATE IN THE DAY AS MONDAY/S SNOW
MOVES OFF TO THE EAST. TEMPERATURES WILL TOP OUT IN THE MID TEENS.
A REINFORCING SHOT OF ARCTIC AIR WILL DROP SOUTH TUESDAY NIGHT
BEHIND THE NEXT COLD FRONT. MOST SNOW WILL FALL TO THE NORTH AND
EAST NEAREST THE BEST MID-LEVEL FORCING AND HIGHEST MOISTURE...
ALTHOUGH SOME SCATTERED LIGHT SNOW IS POSSIBLE ACROSS THE FORECAST
AREA WITH ACCUMULATIONS LESS THAN ONE INCH.
WEDNESDAY THROUGH FRIDAY WILL BE DRY AND UNSEASONABLY COLD. BROAD
SURFACE HIGH PRESSURE DRIFTS ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY THROUGH THIS PERIOD...CENTERED ACROSS NORTHERN MO BY 12Z
FRIDAY. THE REGION REMAINS FULLY ENTRENCHED WITHIN ARCTIC AIR
MASS THROUGH FRIDAY WITH DAILY HIGHS IN THE MID TEENS AND 20S AND
LOWS IN THE SINGLE DIGITS TO TEENS. DEPENDING ON CLOUD COVER...
THURSDAY NIGHT LOWS COULD RIVAL THOSE FROM TUESDAY MORNING.
MID-LEVEL THERMAL RIDGE FINALLY MAKES SOME EASTWARD PROGRESS BY
THE WEEKEND. WARM AIR ADVECTION REGIME SHOULD ALLOW TEMPERATURES
TO CLIMB BACK INTO THE 30S. HOWEVER...BOTH THE 16.12Z GFS AND
ECMWF SHOW THE NEXT STORM SYSTEM LIFTING NORTH FROM THE SOUTHERN
PLAINS OVER THE WEEKEND. THE ECMWF IS FARTHER WEST WITH ITS
PRECIP THAN THE GFS...SO FOR NOW WILL FOLLOW A BLENDED APPROACH
WITH 20 TO 30 POPS AND THE POTENTIAL FOR MIXED PRECIP GIVEN WARMER
TEMPERATURES ALOFT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1134 PM CST SUN NOV 16 2014
CONDITIONS FOR THE MOST PART AROUND THE TAF SITES AS WELL AS IN
THE DAKOTAS AND MN ARE IN THE VFR RANGE...IN THE WAKE OF A COLD
FRONT PASSING THROUGH THE TAF SITES. THERE ARE A FEW ISOLATED
POCKETS OF MVFR STRATUS...MAINLY IN NORTHERN MN. ANTICIPATING
CONDITIONS TO STAY VFR EARLY THIS MORNING...THEN AN MVFR DECK
DEVELOP AROUND OR SHORTLY AFTER 12Z AT BOTH TAF SITES AS THE
AIRMASS BEGINS TO DESTABILIZE. BY 14Z...SOME SNOW SHOWERS SHOULD
GET GOING...AND WITH NORTHWEST WINDS INCREASING TO 15-20 KT WITH
GUSTS OF 20-30 KT...BLOWING SNOW APPEARS LIKELY TO OCCUR AT RST.
THAT BLOWING SNOW SHOULD REDUCE VISIBILITIES TO MVFR...AND
POSSIBLY BRIEFLY IFR AT TIMES BUT PINNING WHEN IS UNCERTAIN AT
THIS TIME. CEILINGS AND VISIBILITIES SHOULD BOTH IMPROVE LATE IN
THE DAY DUE TO LOSS OF DAYTIME HEATING. HAVE KEPT MVFR TO VFR
CEILINGS GOING INTO THE EVENING HOURS...THOUGH ITS ENTIRELY
POSSIBLE THE CLOUDS DISSIPATE TOO WITH LOSS OF HEATING. THE
AFOREMENTIONED WINDS DO LOOK TO PERSIST THROUGH THE EVENING...
THOUGH...AS ARCTIC AIR CONTINUES TO FLOW INTO THE TAF SITES WITH A
TIGHT PRESSURE GRADIENT IN PLACE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST MONDAY FOR MNZ086-
087-094-095.
IA...WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST MONDAY FOR IAZ008-
009-018-019.
&&
$$
UPDATE...AJ
SHORT TERM...ROGERS
LONG TERM...ROGERS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1006 AM EST MON NOV 17 2014
.DISCUSSION...
...SHOWERS/THUNDERSTORMS LIKELY LATE THIS AFTERNOON/EVENING...
...MUCH COLDER TUESDAY AND TUESDAY NIGHT...
...HAZARDOUS MARINE CONDITIONS TUESDAY-WEDNESDAY...
.UPDATE...
WARM SUMMERLIKE TEMPERATURES ARE EXPECTED OVER THE FORECAST AREA
TODAY OUT AHEAD OF A STRONG COLD FRONT. WINDS IN THE 950-700MB
LAYER BOTH STRENGTHENED AND VEERED OVERNIGHT (SOUTH SOUTHWEST 25 -
30 KNOTS) AND WILL CONTINUE TO DO SO THROUGH THE AFTERNOON AS THE
COLD FRONT NEARS. THE MORNING XMR SOUNDING STILL SHOWS A
SIGNIFICANT POCKET OF DRY AIR ABOVE 800MB...THOUGH THERE EXISTS
PLENTY OF LOW LEVEL MOISTURE THAT IS CONTRIBUTING TO A PWAT OF
AROUND 1.5". AS WINDS CONTINUE TO VEER THROUGH THE DAY AND DRAW IN
MOISTURE FROM THE SOUTH AND WEST...EXPECT THE COLUMN TO MOISTEN
FURTHER TO AROUND 2.0" BY THIS EVENING.
AMPLE SUNSHINE SHOULD ALLOW TEMPERATURES TO WARM INTO THE MID AND
UPPER 80S...THREATENING A FEW RECORD HIGHS ACROSS THE AREA (SEE
CLIMATE SECTION BELOW). EXPECT BREEZY CONDITIONS LATE THIS MORNING AND
EARLY THIS AFTERNOON AS MIXING BRINGS DOWN SOME OF THE STRONGER
WINDS ALOFT.
MUCH OF THE AREA SHOULD REMAIN DRY THROUGH EARLY THIS AFTERNOON
AS THE ATMOSPHERE REMAINS RELATIVELY MOISTURE STARVED. A FEW
STORMS SHOULD DEVELOP OUT WELL AHEAD OF THE FRONT AS DAYTIME
HEATING AND INCREASED MOISTURE CONTINUE INTO THE MID AND LATER
AFTERNOON.
EXPECT THE MAIN EVENT AROUND AND AFTER SUNSET AS BETTER
FORCING APPROACHES FROM THE WEST IN ASSOCIATION WITH THE FRONT.
STRONG SOUTHWEST WINDS JUST ABOVE THE SURFACE THROUGH 500MB WILL
CONTRIBUTE TO A GUSTY WIND POTENTIAL IN TODAYS STORMS. FLOW
REMAINS FAIRLY UNIDIRECTIONAL...THUS TORNADO POTENTIAL APPEARS
MINIMAL AT THIS TIME.
LOCAL MODELLING AND HIGH-RES HRRR MODEL POINTS TO A BROKEN LINE OF
SHOWERS AND STORMS APPROACHING OUR NORTHWESTERN ZONES...LAKE/VOLUSIA
COUNTY...AROUND AND JUST AFTER SUNSET. ALL AVAILABLE GUIDANCE
INDICATES A GRADUAL WEAKENING TREND IN THE CONVECTION AS IT MOVES
THROUGH OUR CWA. THIS LINES UP WELL WITH MESOSCALE ANALYSES THAT
POINT TO BETTER DYNAMICS THE FURTHER NORTH YOU GO OVER THE
PENINSULA. EXPECT BROKEN LINE OF SHOWERS AND STORMS TO MOVE
THROUGH THE SPACE AND TREASURE COASTS LATE THIS EVENING AND
OVERNIGHT TONIGHT.
FRONT WILL GRADUALLY WORK ITS WAY DOWN THE PENINSULA
TONIGHT...APPROACHING LAKE AND VOLUSIA COUNTY WELL AFTER SUNSET
AND BEHIND MOST OF THE CONVECTION. BREEZY NORTHWEST WINDS BEHIND
THE FRONT WILL USHER IN THE COLDEST AIR MASS OF THE SEASON FOR
TOMORROW. MORE ON THAT IN THIS AFTERNOONS PACKAGE.
&&
.AVIATION...
INCREASING SOUTH TO SOUTHWEST FLOW TODAY AT ALL TERMINALS. LOW
CLOUDS/STRATUS THIS MORNING SHOULD MIX OUT AS DAYTIME HEATING
CONTINUES...LIFTING CURRENT MVFR/IFR CIGS TO VFR. ISOLATED SHRA
AND PERHAPS A TSRA COULD DEVELOP THIS AFTERNOON OUT AHEAD OF A
BROKEN LINE OF SHRA AND TSRA THAT WILL APPROACH OUR NORTHWESTERN
TERMINALS (LEE AND DAB) AROUND AND AFTER SUNSET. EXPECT LINE OF
CONVECTION TO MOVE THROUGH AS EVENING PROGRESSES. GUSTY WNW/NW
WINDS EXPECTED BEHIND FRONTAL BOUNDARY AS IT MOVES THROUGH
TONIGHT.
&&
.MARINE...TODAY-TONIGHT...A STRONG COLD FRONT WILL PASS OVER THE
COASTAL WATERS OVERNIGHT TONIGHT. SHOWER CHANCES WILL INCREASE FROM NORTH
TO SOUTH INTO THE AFTERNOON WITH LIGHTNING STORM CHANCES
INCREASING LATE TODAY/TONIGHT. ACTIVITY LATER TODAY WILL MOVE
QUICKLY OFFSHORE WITH CLOUD TO WATER LIGHTNING...HEAVY RAINFALL
AND GUSTY WINDS IN EXCESS OF 35 KTS POSSIBLE. SSE WINDS VEER TO
SSW THIS MORNING AND EARLY AFTERNOON AHEAD OF THE FRONT...THEN
GRADUALLY TOWARD THE W/NW BEHIND IT OVERNIGHT. WIND SPEEDS
GENERALLY 10-15 KTS AND GUSTY NEAR SHORE AND 15-20 KTS AND GUSTY
OFFSHORE/NORTH OF SEBASTIAN INLET INTO THIS EVENING.
NORTHWEST WINDS SPREADING SOUTHWARD BEHIND THE FRONT LATE TONIGHT
WILL INCREASE TO 20-25 KTS AND GUSTY. A SMALL CRAFT ADVISORY WILL
GO INTO EFFECT FOR THE OFFSHORE WATERS NORTH OF SEBASTIAN INLET
AND NEAR SHORE NORTH LEG AT 00Z AND SPREAD AREAWIDE AT 06Z. SEAS
GENERALLY 3-5 FT BUT WILL APPROACH 6 FT WELL OFFSHORE NORTH OF
SEBASTIAN INLET. TONIGHT...SEAS WILL BUILD NEAR SHORE 4-6 FT LATE
OVERNIGHT NORTH OF THE CAPE AND UP TO 7 FT (LATE) NORTH OFFSHORE
LEG.
&&
.CLIMATE...HIGH TEMPERATURES ARE FORECAST NEAR RECORD LEVELS AT VERO
BEACH TODAY.
RECORD HIGHS FOR TODAY 17 NOV:
DAB 88 IN 1988.
MCO 89 IN 1957.
MLB 88 IN 1948.
VRB 86 IN 2011.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 84 48 60 38 / 60 80 20 10
MCO 83 55 60 39 / 60 80 20 10
MLB 86 59 63 43 / 50 80 40 10
VRB 86 64 66 49 / 60 80 50 10
LEE 82 48 57 34 / 70 80 10 10
SFB 83 53 60 38 / 60 80 20 10
ORL 83 52 60 40 / 60 80 20 10
FPR 86 64 66 50 / 60 70 50 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 10 PM EST TUESDAY
FOR COASTAL WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD
COUNTY LINE OUT 20 NM.
SMALL CRAFT ADVISORY FROM 1 AM TUESDAY TO 10 AM EST WEDNESDAY
FOR COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER INLET
OUT 20 NM-COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE
TO SEBASTIAN INLET OUT 20 NM-WATERS FROM SEBASTIAN INLET TO
JUPITER INLET 20 TO 60 NM OFFSHORE.
SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 10 AM EST
WEDNESDAY FOR WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD
COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS FROM VOLUSIA
BREVARD COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE.
&&
$$
IMPACT WEATHER/RADAR...MOSES
AVIATION/FORECAST...ULRICH
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
928 AM EST MON NOV 17 2014
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 331 AM EST MON NOV 17 2014
WIDESPREAD SNOW WILL END THIS MORNING WITH SCATTERED SNOW SHOWERS
INTO THE EVENING AS MUCH COLDER AIR SPREADS INTO THE OHIO VALLEY.
VERY COLD WEATHER WILL CONTINUE THROUGH MIDWEEK...WITH CHANCES FOR
SNOW AGAIN ON WEDNESDAY AS A WEAK UPPER LEVEL WAVE PASSES THROUGH
THE REGION. LOW PRESSURE TRACKING INTO THE REGION OVER THE WEEKEND
WILL BRING A RETURN TO UNSETTLED WEATHER ALONG WITH WARMER
TEMPERATURES.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 848 AM EST MON NOV 17 2014
1345Z UPDATE...QUICK UPDATE THIS MORNING TO REMOVE COUNTIES FROM
THE ADVISORY AREA WHERE THE BULK OF THE SNOW HAS ENDED. NEEDED TO
DO A LITTLE EXTENSION FOR FAR SE/EASTERN TIER OF COUNTIES WHERE
SNOW IS A LITTLE SLOWER THAN EXPECTED TO EXIT THE AREA THIS
MORNING. THESE COUNTIES SHOULD SEE AN ADDITIONAL 1 INCH...POSSIBLY UP
TO 2 INCHES BEFORE THE ADVISORY IS NOW SET TO THROUGH 11AM.
ALSO MADE SOME MINOR ADJUSTMENTS TO ACCOUNT FOR THE LATEST TRENDS
IN TEMP/SKY/WIND. PREVIOUS DISCUSSION FOLLOWS...
STEADY SNOWFALL CONTINUES ALONG AND SOUTHEAST OF A TERRE HAUTE-INDY
METRO-MUNCIE LINE AS OF 08Z. BACK EDGE OF THE PRECIP SHIELD HAS
BACKPEDALED NORTHWEST OVER THE LAST 2-3 HOURS AS THE SHARP UPPER
WAVE QUICKLY TRACKS INTO THE LOWER MISSISSIPPI VALLEY. TEMPS WERE
GENERALLY IN THE 20S AND FALLING WITH THE INITIAL ARRIVAL OF THE
ARCTIC AIRMASS.
INITIAL ISSUE FOCUSES ON THE SNOW CONTINUING EARLY THIS MORNING WITH
ITS DEPARTURE OFF TO THE EAST BETWEEN 12-15Z. DESPITE THE PIVOT BACK
TO THE WEST OF THE PRECIP SHIELD...DO NOT EXPECT IT TO SHIFT MUCH
FURTHER NORTHWEST FROM ITS CURRENT POSITION AS UPPER LEVEL ENERGY IS
QUICKLY APPROACHING FROM THE SOUTHWEST WHILE THE MAIN SURFACE LOW
TRACKS INTO NORTHERN GEORGIA. HRRR AND THE WRF BOTH HAVE A NICE
HANDLE ON THE LOCATION OF THE SNOWFALL AND EXPECTED EVOLUTION
THROUGH DAYBREAK. SNOW WILL BEGIN TO SHIFT EAST AFTER 09-10Z...WITH
PRECIP ENDING OVER FAR EASTERN COUNTIES BY 14-15Z. WITH THE
POTENTIAL FOR ANOTHER INCH OR TWO OF ADDITIONAL ACCUM OVER THE
SOUTHEAST HALF OF THE FORECAST AREA...WILL CONTINUE WITH THE
ADVISORY IN ITS CURRENT STATE THROUGH 14Z. HEAVIER SNOWFALL WILL
REMAIN SOUTHEAST OF THE INDY METRO...BUT STILL QUITE POSSIBLE TO
TACK ON ANOTHER HALF INCH OR SO IN THE CITY BEFORE SNOW ENDS.
FURTHER NORTHWEST...EXPECT LITTLE MORE THAN FLURRIES OVER THE NEXT
FEW HOURS.
DRIER AIR WILL WRAP INTO THE REGION BEHIND THE SNOWFALL LATER THIS
MORNING AND MAY EVEN BRING A FEW PEAKS OF SUNSHINE THROUGH MIDDAY.
COLD POOL BEGINS TO SETTLE OVER THE REGION DURING THE AFTERNOON AS
THE UPPER LOW PINWHEELS INTO THE NORTHERN GREAT LAKES. AS HAS BEEN
DISCUSSED OVER THE LAST FEW DAYS...POTENTIAL FOR SCATTERED SNOW
SHOWERS TO REDEVELOP THIS AFTERNOON AND EVENING. MODELS IN GENERAL
TEND TO STRUGGLE IN THIS SETUP AND OFTEN UNDER-DO THE SNOW POTENTIAL
BECAUSE THEY DO NOT CAPTURE THE MESOSCALE FEATURES WELL. THE WRF
DOES A BETTER JOB IN THIS REGARD AND NOW THAT WE ARE WITHIN ITS
WINDOW...IT IS SUPPORTING POTENTIAL FOR SCATTERED CONVECTIVE SNOW
SHOWERS/SQUALLS LATER THIS AFTERNOON...AND THESE COULD CAUSE SOME
PROBLEMS OVER THE REGION.
PLENTY OF MID LEVEL ENERGY ROTATING AROUND THE BASE OF THE UPPER LOW
AND THROUGH THE REGION. THIS COMBINED WITH INTENSIFYING COLD
ADVECTION AND SHALLOW INSTABILITY WITH STEEPENING LAPSE RATES TO
850MB SUPPORT CONVECTIVE SNOW SHOWERS. WITH WIND GUSTS STEADILY
STRENGTHENING TO AROUND 30MPH THIS AFTERNOON...THESE SNOW
SHOWERS/SQUALLS HAVE THE POTENTIAL TO CREATE A GREATER IMPACT ON
TRAVEL THAN THE SNOW EXPERIENCED SUNDAY NIGHT AND EARLY THIS
MORNING. WHILE SNOWFALL WILL BE ONLY A DUSTING TO A FEW TENTHS OF AN
INCH AT BEST...THE SNOW WILL BE DRIER AND MUCH EASIER TO BLOW AROUND
WITH THE POTENTIAL FOR LOCALLY REDUCED VISIBILITIES IN HEAVIER SNOW
SHOWERS. AS CRAZY AS THIS SOUNDS...HAVE A GROWING CONCERN THAT THE
LATE AFTERNOON/EVENING RUSH HOUR COULD BE MORE GREATLY IMPACTED THAN
THIS MORNING. WILL BE INTRODUCING AN SPS TO HIGHLIGHT THESE THREATS
FOR LATER TODAY.
TEMPS...HIGHS ARE TRICKY FOR TODAY CONSIDERING THEY ARE LARGELY
LOWER THAN CURRENT READINGS THIS MORNING. MAY SEE A BRIEF RISE IN
TEMPS THROUGH MIDDAY WITH FALLING TEMPS THEREAFTER AS THE STRONGER
COLD ADVECTION ARRIVES. A MOS BLEND WAS REASONABLE FOR HIGHS...THEN
USED A MIX OF NAM/LAMP DATA FOR THE FALLING TEMPS THIS AFTERNOON.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 331 AM EST MON NOV 17 2014
FORECAST CHALLENGES FOCUS ON TEMPS THROUGH THE PERIOD AND SNOW
CHANCES...PRIMARILY WEDNESDAY.
AN EVEN STRONGER BLAST OF COLD AIR OF POLAR ORIGIN POISED TO
OVERSPREAD THE OHIO VALLEY AND GREAT LAKES FOR MOST OF THE SHORT
TERM. AFOREMENTIONED SCATTERED SNOW SHOWERS WILL BE ONGOING THIS
EVENING...LIKELY NOT DIMINISHING IN INTENSITY AND COVERAGE UNTIL
CLOSER TO MIDNIGHT. WILL MAINTAIN SCATTERED FLURRIES OVERNIGHT WITH
STILL PLENTY OF FORCING ALOFT AND WILL HAVE TO MONITOR AS COULD EVEN
SEE A FEW SNOW SHOWERS LINGER WELL INTO THE OVERNIGHT.
UPPER TROUGH AND COLD POOL ALOFT CENTERED OVER THE REGION EARLY
TUESDAY...GRADUALLY LIFTING OUT BY LATE TUESDAY AS THE UPPER LOW
SHIFTS EAST INTO QUEBEC. WILL MAINTAIN A MENTION OF SCATTERED
FLURRIES INTO THE AFTERNOON...ENDING FROM WEST TO EAST AS FORCING
ALOFT WEAKENS. WEAK SURFACE RIDGING WILL QUICKLY TRACK ACROSS THE
REGION TUESDAY NIGHT BRINGING A BRIEF PERIOD OF CLEARING BEFORE
CLOUDS INCREASE IN ADVANCE OF ANOTHER APPROACHING WAVE ALOFT FROM
THE NORTHWEST.
THE UPPER WAVE WILL SWING ACROSS THE LOWER GREAT LAKES WEDNESDAY
WITH LIGHT SNOW SHOWERS IMPACTING PRIMARILY THE NORTHERN HALF OF THE
FORECAST AREA. COULD SEE SOME VERY LIGHT ACCUMS NORTH OF I-70 FROM A
DUSTING UP TO CLOSE TO AN INCH IN FAR NORTHERN COUNTIES BY LATE DAY
WEDNESDAY. BUMPED UP TO CHANCE POPS IN THE NORTH WEDNESDAY. SKIES
WILL CLEAR WEDNESDAY NIGHT AS HIGH PRESSURE REESTABLISHES ALONG WITH
A RENEWED SURGE OF COLDER AIR.
TEMPS...DEFINITELY THE BIG STORY OF THE SHORT TERM. UNDERCUT MOS
GUIDANCE FOR LOWS TONIGHT WITH SNOWCOVER AND 850MB TEMPS BOTTOMING
OUT AT -21 TO -20C BY TUESDAY MORNING. THINK MOST LOCATIONS GET INTO
THE SINGLE DIGITS. ONLY MODEST RECOVERY FOR TUESDAY AS HIGHS WILL
END UP RIGHT AROUND 20. LEANED CLOSER TO COOLER END OF GUIDANCE THE
REST OF THE WAY...WITH HIGHS RECOVERING INTO THE LOWER/MID 30S FOR
WEDNESDAY.
INDY RECORDS FOR TUESDAY...RECORD LOW IS 5 (1880) AND RECORD LOW MAX
TEMP IS 20 (1880). POTENTIAL FOR THE FIRST SINGLE DIGIT LOW IN
NOVEMBER SINCE 11/30/1976.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ISSUED AT 331 AM EST MON NOV 17 2014
ENSEMBLES SUGGEST A DEEP UPPER TROUGH INITIALLY OVER THE EASTERN
PARTS OF THE COUNTRY WILL BE LIFTING OFF TO THE NORTHEAST BY LATE IN
THE WEEK...LEAVING A MORE ZONAL FLOW OVER THE LOCAL AREA.
THE NEXT SYSTEM THAT MAY AFFECT THE AREA DURING THIS PERIOD WILL BE
A DISTURBANCE OF PACIFIC ORIGIN. THERE IS STILL QUITE A BIT OF
SPREAD AMONG THE ENSEMBLES AS TO THE TIMING OF THIS FEATURE...FROM
AS EARLY AS FRIDAY NIGHT TO AS LATE AS SATURDAY NIGHT OR SUNDAY. FOR
NOW...WILL BROADBRUSH POPS STARTING FRIDAY NIGHT THROUGH NEXT
SUNDAY. THERE MAY STILL BE ENOUGH RESIDUAL COLD AIR AROUND FOR MIXED
PRECIPITATION OVER PARTS OF THE AREA FRIDAY NIGHT THROUGH SATURDAY
NIGHT...BUT ENSEMBLES SUGGEST LITTLE THREAT FOR SIGNIFICANT
ACCUMULATIONS AT THIS TIME.
&&
.AVIATION /DISCUSSION FOR THE 171500Z KIND TAF UPDATE/...
ISSUED AT 928 AM EST MON NOV 17 2014
MINOR TWEAKS MADE TO KIND TAF TO BETTER MATCH CURRENT CONDITIONS.
NO OTHER CHANGES ARE NEEDED AT THIS TIME.
PREVIOUS AVIATION DISCUSSION FOLLOWS...
BACK EDGE OF LOWER MVFR CEILINGS AROUND 012 CURRENTLY MOVING INTO
THE WESTERN BORDER ZONES. EXTRAPOLATION AND SHORT TERM MODELS
SUGGEST THESE LOWER CEILINGS WILL SCATTER OUT OVER THE TAF SITES BY
171400Z.
LOW LEVEL LAPSE RATES BECOME NEAR DRY ADIABATIC BY EARLY
AFTERNOON...SO EXPECTING VFR CEILINGS AROUND 040 TO DEVELOP BY THAT
TIME...AS WELL AS SCATTERED SNOW SHOWERS. MODEL GUIDANCE SUGGESTS
BRIEF IFR VISIBILITY RESTRICTIONS POSSIBLE IN THE HEAVIER
SHOWERS...BUT DUE TO THE SCATTERED NATURE OF THE SHOWERS...WILL
REFRAIN FROM AN EXPLICIT MENTION AT THIS TIME.
SURFACE WINDS EXPECTED TO GRADUALLY INCREASE AS THE MORNING GOES
BY...WITH GUSTS AROUND 25 KTS FROM 270-300 DEGREES EXPECTED BY THIS
AFTERNOON.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR INZ042-
049-057-064-065-071-072.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS/JH
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
909 AM EST MON NOV 17 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 331 AM EST MON NOV 17 2014
WIDESPREAD SNOW WILL END THIS MORNING WITH SCATTERED SNOW SHOWERS
INTO THE EVENING AS MUCH COLDER AIR SPREADS INTO THE OHIO VALLEY.
VERY COLD WEATHER WILL CONTINUE THROUGH MIDWEEK...WITH CHANCES FOR
SNOW AGAIN ON WEDNESDAY AS A WEAK UPPER LEVEL WAVE PASSES THROUGH
THE REGION. LOW PRESSURE TRACKING INTO THE REGION OVER THE WEEKEND
WILL BRING A RETURN TO UNSETTLED WEATHER ALONG WITH WARMER
TEMPERATURES.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 848 AM EST MON NOV 17 2014
1345Z UPDATE...QUICK UPDATE THIS MORNING TO REMOVE COUNTIES FROM
THE ADVISORY AREA WHERE THE BULK OF THE SNOW HAS ENDED. NEEDED TO
DO A LITTLE EXTENSION FOR FAR SE/EASTERN TIER OF COUNTIES WHERE
SNOW IS A LITTLE SLOWER THAN EXPECTED TO EXIT THE AREA THIS
MORNING. THESE COUNTIES SHOULD SEE AN ADDITIONAL 1 INCH...POSSIBLY UP
TO 2 INCHES BEFORE THE ADVISORY IS NOW SET TO THROUGH 11AM.
ALSO MADE SOME MINOR ADJUSTMENTS TO ACCOUNT FOR THE LATEST TRENDS
IN TEMP/SKY/WIND. PREVIOUS DISCUSSION FOLLOWS...
STEADY SNOWFALL CONTINUES ALONG AND SOUTHEAST OF A TERRE HAUTE-INDY
METRO-MUNCIE LINE AS OF 08Z. BACK EDGE OF THE PRECIP SHIELD HAS
BACKPEDALED NORTHWEST OVER THE LAST 2-3 HOURS AS THE SHARP UPPER
WAVE QUICKLY TRACKS INTO THE LOWER MISSISSIPPI VALLEY. TEMPS WERE
GENERALLY IN THE 20S AND FALLING WITH THE INITIAL ARRIVAL OF THE
ARCTIC AIRMASS.
INITIAL ISSUE FOCUSES ON THE SNOW CONTINUING EARLY THIS MORNING WITH
ITS DEPARTURE OFF TO THE EAST BETWEEN 12-15Z. DESPITE THE PIVOT BACK
TO THE WEST OF THE PRECIP SHIELD...DO NOT EXPECT IT TO SHIFT MUCH
FURTHER NORTHWEST FROM ITS CURRENT POSITION AS UPPER LEVEL ENERGY IS
QUICKLY APPROACHING FROM THE SOUTHWEST WHILE THE MAIN SURFACE LOW
TRACKS INTO NORTHERN GEORGIA. HRRR AND THE WRF BOTH HAVE A NICE
HANDLE ON THE LOCATION OF THE SNOWFALL AND EXPECTED EVOLUTION
THROUGH DAYBREAK. SNOW WILL BEGIN TO SHIFT EAST AFTER 09-10Z...WITH
PRECIP ENDING OVER FAR EASTERN COUNTIES BY 14-15Z. WITH THE
POTENTIAL FOR ANOTHER INCH OR TWO OF ADDITIONAL ACCUM OVER THE
SOUTHEAST HALF OF THE FORECAST AREA...WILL CONTINUE WITH THE
ADVISORY IN ITS CURRENT STATE THROUGH 14Z. HEAVIER SNOWFALL WILL
REMAIN SOUTHEAST OF THE INDY METRO...BUT STILL QUITE POSSIBLE TO
TACK ON ANOTHER HALF INCH OR SO IN THE CITY BEFORE SNOW ENDS.
FURTHER NORTHWEST...EXPECT LITTLE MORE THAN FLURRIES OVER THE NEXT
FEW HOURS.
DRIER AIR WILL WRAP INTO THE REGION BEHIND THE SNOWFALL LATER THIS
MORNING AND MAY EVEN BRING A FEW PEAKS OF SUNSHINE THROUGH MIDDAY.
COLD POOL BEGINS TO SETTLE OVER THE REGION DURING THE AFTERNOON AS
THE UPPER LOW PINWHEELS INTO THE NORTHERN GREAT LAKES. AS HAS BEEN
DISCUSSED OVER THE LAST FEW DAYS...POTENTIAL FOR SCATTERED SNOW
SHOWERS TO REDEVELOP THIS AFTERNOON AND EVENING. MODELS IN GENERAL
TEND TO STRUGGLE IN THIS SETUP AND OFTEN UNDER-DO THE SNOW POTENTIAL
BECAUSE THEY DO NOT CAPTURE THE MESOSCALE FEATURES WELL. THE WRF
DOES A BETTER JOB IN THIS REGARD AND NOW THAT WE ARE WITHIN ITS
WINDOW...IT IS SUPPORTING POTENTIAL FOR SCATTERED CONVECTIVE SNOW
SHOWERS/SQUALLS LATER THIS AFTERNOON...AND THESE COULD CAUSE SOME
PROBLEMS OVER THE REGION.
PLENTY OF MID LEVEL ENERGY ROTATING AROUND THE BASE OF THE UPPER LOW
AND THROUGH THE REGION. THIS COMBINED WITH INTENSIFYING COLD
ADVECTION AND SHALLOW INSTABILITY WITH STEEPENING LAPSE RATES TO
850MB SUPPORT CONVECTIVE SNOW SHOWERS. WITH WIND GUSTS STEADILY
STRENGTHENING TO AROUND 30MPH THIS AFTERNOON...THESE SNOW
SHOWERS/SQUALLS HAVE THE POTENTIAL TO CREATE A GREATER IMPACT ON
TRAVEL THAN THE SNOW EXPERIENCED SUNDAY NIGHT AND EARLY THIS
MORNING. WHILE SNOWFALL WILL BE ONLY A DUSTING TO A FEW TENTHS OF AN
INCH AT BEST...THE SNOW WILL BE DRIER AND MUCH EASIER TO BLOW AROUND
WITH THE POTENTIAL FOR LOCALLY REDUCED VISIBILITIES IN HEAVIER SNOW
SHOWERS. AS CRAZY AS THIS SOUNDS...HAVE A GROWING CONCERN THAT THE LATE
AFTERNOON/EVENING RUSH HOUR COULD BE MORE GREATLY IMPACTED THAN THIS
MORNING. WILL BE INTRODUCING AN SPS TO HIGHLIGHT THESE THREATS FOR
LATER TODAY.
TEMPS...HIGHS ARE TRICKY FOR TODAY CONSIDERING THEY ARE LARGELY
LOWER THAN CURRENT READINGS THIS MORNING. MAY SEE A BRIEF RISE IN
TEMPS THROUGH MIDDAY WITH FALLING TEMPS THEREAFTER AS THE STRONGER
COLD ADVECTION ARRIVES. A MOS BLEND WAS REASONABLE FOR HIGHS...THEN
USED A MIX OF NAM/LAMP DATA FOR THE FALLING TEMPS THIS AFTERNOON.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 331 AM EST MON NOV 17 2014
FORECAST CHALLENGES FOCUS ON TEMPS THROUGH THE PERIOD AND SNOW
CHANCES...PRIMARILY WEDNESDAY.
AN EVEN STRONGER BLAST OF COLD AIR OF POLAR ORIGIN POISED TO
OVERSPREAD THE OHIO VALLEY AND GREAT LAKES FOR MOST OF THE SHORT
TERM. AFOREMENTIONED SCATTERED SNOW SHOWERS WILL BE ONGOING THIS
EVENING...LIKELY NOT DIMINISHING IN INTENSITY AND COVERAGE UNTIL
CLOSER TO MIDNIGHT. WILL MAINTAIN SCATTERED FLURRIES OVERNIGHT WITH
STILL PLENTY OF FORCING ALOFT AND WILL HAVE TO MONITOR AS COULD EVEN
SEE A FEW SNOW SHOWERS LINGER WELL INTO THE OVERNIGHT.
UPPER TROUGH AND COLD POOL ALOFT CENTERED OVER THE REGION EARLY
TUESDAY...GRADUALLY LIFTING OUT BY LATE TUESDAY AS THE UPPER LOW
SHIFTS EAST INTO QUEBEC. WILL MAINTAIN A MENTION OF SCATTERED
FLURRIES INTO THE AFTERNOON...ENDING FROM WEST TO EAST AS FORCING
ALOFT WEAKENS. WEAK SURFACE RIDGING WILL QUICKLY TRACK ACROSS THE
REGION TUESDAY NIGHT BRINGING A BRIEF PERIOD OF CLEARING BEFORE
CLOUDS INCREASE IN ADVANCE OF ANOTHER APPROACHING WAVE ALOFT FROM
THE NORTHWEST.
THE UPPER WAVE WILL SWING ACROSS THE LOWER GREAT LAKES WEDNESDAY
WITH LIGHT SNOW SHOWERS IMPACTING PRIMARILY THE NORTHERN HALF OF THE
FORECAST AREA. COULD SEE SOME VERY LIGHT ACCUMS NORTH OF I-70 FROM A
DUSTING UP TO CLOSE TO AN INCH IN FAR NORTHERN COUNTIES BY LATE DAY
WEDNESDAY. BUMPED UP TO CHANCE POPS IN THE NORTH WEDNESDAY. SKIES
WILL CLEAR WEDNESDAY NIGHT AS HIGH PRESSURE REESTABLISHES ALONG WITH
A RENEWED SURGE OF COLDER AIR.
TEMPS...DEFINITELY THE BIG STORY OF THE SHORT TERM. UNDERCUT MOS
GUIDANCE FOR LOWS TONIGHT WITH SNOWCOVER AND 850MB TEMPS BOTTOMING
OUT AT -21 TO -20C BY TUESDAY MORNING. THINK MOST LOCATIONS GET INTO
THE SINGLE DIGITS. ONLY MODEST RECOVERY FOR TUESDAY AS HIGHS WILL
END UP RIGHT AROUND 20. LEANED CLOSER TO COOLER END OF GUIDANCE THE
REST OF THE WAY...WITH HIGHS RECOVERING INTO THE LOWER/MID 30S FOR
WEDNESDAY.
INDY RECORDS FOR TUESDAY...RECORD LOW IS 5 (1880) AND RECORD LOW MAX
TEMP IS 20 (1880). POTENTIAL FOR THE FIRST SINGLE DIGIT LOW IN
NOVEMBER SINCE 11/30/1976.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ISSUED AT 331 AM EST MON NOV 17 2014
ENSEMBLES SUGGEST A DEEP UPPER TROUGH INITIALLY OVER THE EASTERN
PARTS OF THE COUNTRY WILL BE LIFTING OFF TO THE NORTHEAST BY LATE IN
THE WEEK...LEAVING A MORE ZONAL FLOW OVER THE LOCAL AREA.
THE NEXT SYSTEM THAT MAY AFFECT THE AREA DURING THIS PERIOD WILL BE
A DISTURBANCE OF PACIFIC ORIGIN. THERE IS STILL QUITE A BIT OF
SPREAD AMONG THE ENSEMBLES AS TO THE TIMING OF THIS FEATURE...FROM
AS EARLY AS FRIDAY NIGHT TO AS LATE AS SATURDAY NIGHT OR SUNDAY. FOR
NOW...WILL BROADBRUSH POPS STARTING FRIDAY NIGHT THROUGH NEXT
SUNDAY. THERE MAY STILL BE ENOUGH RESIDUAL COLD AIR AROUND FOR MIXED
PRECIPITATION OVER PARTS OF THE AREA FRIDAY NIGHT THROUGH SATURDAY
NIGHT...BUT ENSEMBLES SUGGEST LITTLE THREAT FOR SIGNIFICANT
ACCUMULATIONS AT THIS TIME.
&&
.AVIATION /DISCUSSION FOR THE 171200Z TAFS/...
ISSUED AT 538 AM EST MON NOV 17 2014
BACK EDGE OF LOWER MVFR CEILINGS AROUND 012 CURRENTLY MOVING INTO
THE WESTERN BORDER ZONES. EXTRAPOLATION AND SHORT TERM MODELS
SUGGEST THESE LOWER CEILINGS WILL SCATTER OUT OVER THE TAF SITES BY
171400Z.
LOW LEVEL LAPSE RATES BECOME NEAR DRY ADIABATIC BY EARLY
AFTERNOON...SO EXPECTING VFR CEILINGS AROUND 040 TO DEVELOP BY THAT
TIME...AS WELL AS SCATTERED SNOW SHOWERS. MODEL GUIDANCE SUGGESTS
BRIEF IFR VISIBILITY RESTRICTIONS POSSIBLE IN THE HEAVIER
SHOWERS...BUT DUE TO THE SCATTERED NATURE OF THE SHOWERS...WILL
REFRAIN FROM AN EXPLICIT MENTION AT THIS TIME.
SURFACE WINDS EXPECTED TO GRADUALLY INCREASE AS THE MORNING GOES
BY...WITH GUSTS AROUND 25 KTS FROM 270-300 DEGREES EXPECTED BY THIS
AFTERNOON.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR INZ042-
049-057-064-065-071-072.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
538 AM EST MON NOV 17 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 331 AM EST MON NOV 17 2014
WIDESPREAD SNOW WILL END THIS MORNING WITH SCATTERED SNOW SHOWERS
INTO THE EVENING AS MUCH COLDER AIR SPREADS INTO THE OHIO VALLEY.
VERY COLD WEATHER WILL CONTINUE THROUGH MIDWEEK...WITH CHANCES FOR
SNOW AGAIN ON WEDNESDAY AS A WEAK UPPER LEVEL WAVE PASSES THROUGH
THE REGION. LOW PRESSURE TRACKING INTO THE REGION OVER THE WEEKEND
WILL BRING A RETURN TO UNSETTLED WEATHER ALONG WITH WARMER
TEMPERATURES.
&&
.NEAR TERM /TODAY/...
ISSUED AT 331 AM EST MON NOV 17 2014
STEADY SNOWFALL CONTINUES ALONG AND SOUTHEAST OF A TERRE HAUTE-INDY
METRO-MUNCIE LINE AS OF 08Z. BACK EDGE OF THE PRECIP SHIELD HAS
BACKPEDALED NORTHWEST OVER THE LAST 2-3 HOURS AS THE SHARP UPPER
WAVE QUICKLY TRACKS INTO THE LOWER MISSISSIPPI VALLEY. TEMPS WERE
GENERALLY IN THE 20S AND FALLING WITH THE INITIAL ARRIVAL OF THE
ARCTIC AIRMASS.
INITIAL ISSUE FOCUSES ON THE SNOW CONTINUING EARLY THIS MORNING WITH
ITS DEPARTURE OFF TO THE EAST BETWEEN 12-15Z. DESPITE THE PIVOT BACK
TO THE WEST OF THE PRECIP SHIELD...DO NOT EXPECT IT TO SHIFT MUCH
FURTHER NORTHWEST FROM ITS CURRENT POSITION AS UPPER LEVEL ENERGY IS
QUICKLY APPROACHING FROM THE SOUTHWEST WHILE THE MAIN SURFACE LOW
TRACKS INTO NORTHERN GEORGIA. HRRR AND THE WRF BOTH HAVE A NICE
HANDLE ON THE LOCATION OF THE SNOWFALL AND EXPECTED EVOLUTION
THROUGH DAYBREAK. SNOW WILL BEGIN TO SHIFT EAST AFTER 09-10Z...WITH
PRECIP ENDING OVER FAR EASTERN COUNTIES BY 14-15Z. WITH THE
POTENTIAL FOR ANOTHER INCH OR TWO OF ADDITIONAL ACCUM OVER THE
SOUTHEAST HALF OF THE FORECAST AREA...WILL CONTINUE WITH THE
ADVISORY IN ITS CURRENT STATE THROUGH 14Z. HEAVIER SNOWFALL WILL
REMAIN SOUTHEAST OF THE INDY METRO...BUT STILL QUITE POSSIBLE TO
TACK ON ANOTHER HALF INCH OR SO IN THE CITY BEFORE SNOW ENDS.
FURTHER NORTHWEST...EXPECT LITTLE MORE THAN FLURRIES OVER THE NEXT
FEW HOURS.
DRIER AIR WILL WRAP INTO THE REGION BEHIND THE SNOWFALL LATER THIS
MORNING AND MAY EVEN BRING A FEW PEAKS OF SUNSHINE THROUGH MIDDAY.
COLD POOL BEGINS TO SETTLE OVER THE REGION DURING THE AFTERNOON AS
THE UPPER LOW PINWHEELS INTO THE NORTHERN GREAT LAKES. AS HAS BEEN
DISCUSSED OVER THE LAST FEW DAYS...POTENTIAL FOR SCATTERED SNOW
SHOWERS TO REDEVELOP THIS AFTERNOON AND EVENING. MODELS IN GENERAL
TEND TO STRUGGLE IN THIS SETUP AND OFTEN UNDERDO THE SNOW POTENTIAL
BECAUSE THEY DO NOT CAPTURE THE MESOSCALE FEATURES WELL. THE WRF
DOES A BETTER JOB IN THIS REGARD AND NOW THAT WE ARE WITHIN ITS
WINDOW...IT IS SUPPORTING POTENTIAL FOR SCATTERED CONVECTIVE SNOW
SHOWERS/SQUALLS LATER THIS AFTERNOON...AND THESE COULD CAUSE SOME
PROBLEMS OVER THE REGION.
PLENTY OF MID LEVEL ENERGY ROTATING AROUND THE BASE OF THE UPPER LOW
AND THROUGH THE REGION. THIS COMBINED WITH INTENSIFYING COLD
ADVECTION AND SHALLOW INSTABILITY WITH STEEPENING LAPSE RATES TO
850MB SUPPORT CONVECTIVE SNOW SHOWERS. WITH WIND GUSTS STEADILY
STRENGTHENING TO AROUND 30MPH THIS AFTERNOON...THESE SNOW
SHOWERS/SQUALLS HAVE THE POTENTIAL TO CREATE A GREATER IMPACT ON
TRAVEL THAN THE SNOW EXPERIENCED SUNDAY NIGHT AND EARLY THIS
MORNING. WHILE SNOWFALL WILL BE ONLY A DUSTING TO A FEW TENTHS OF AN
INCH AT BEST...THE SNOW WILL BE DRIER AND MUCH EASIER TO BLOW AROUND
WITH THE POTENTIAL FOR LOCALLY REDUCED VISIBILITIES IN HEAVIER SNOW
SHOWERS. AS CRAZY AS THIS SOUNDS...HAVE A GROWING CONCERN THAT THE LATE
AFTERNOON/EVENING RUSH HOUR COULD BE MORE GREATLY IMPACTED THAN THIS
MORNING. WILL BE INTRODUCING AN SPS TO HIGHLIGHT THESE THREATS FOR
LATER TODAY.
TEMPS...HIGHS ARE TRICKY FOR TODAY CONSIDERING THEY ARE LARGELY
LOWER THAN CURRENT READINGS THIS MORNING. MAY SEE A BRIEF RISE IN
TEMPS THROUGH MIDDAY WITH FALLING TEMPS THEREAFTER AS THE STRONGER
COLD ADVECTION ARRIVES. A MOS BLEND WAS REASONABLE FOR HIGHS...THEN
USED A MIX OF NAM/LAMP DATA FOR THE FALLING TEMPS THIS AFTERNOON.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 331 AM EST MON NOV 17 2014
FORECAST CHALLENGES FOCUS ON TEMPS THROUGH THE PERIOD AND SNOW
CHANCES...PRIMARILY WEDNESDAY.
AN EVEN STRONGER BLAST OF COLD AIR OF POLAR ORIGIN POISED TO
OVERSPREAD THE OHIO VALLEY AND GREAT LAKES FOR MOST OF THE SHORT
TERM. AFOREMENTIONED SCATTERED SNOW SHOWERS WILL BE ONGOING THIS
EVENING...LIKELY NOT DIMINISHING IN INTENSITY AND COVERAGE UNTIL
CLOSER TO MIDNIGHT. WILL MAINTAIN SCATTERED FLURRIES OVERNIGHT WITH
STILL PLENTY OF FORCING ALOFT AND WILL HAVE TO MONITOR AS COULD EVEN
SEE A FEW SNOW SHOWERS LINGER WELL INTO THE OVERNIGHT.
UPPER TROUGH AND COLD POOL ALOFT CENTERED OVER THE REGION EARLY
TUESDAY...GRADUALLY LIFTING OUT BY LATE TUESDAY AS THE UPPER LOW
SHIFTS EAST INTO QUEBEC. WILL MAINTAIN A MENTION OF SCATTERED
FLURRIES INTO THE AFTERNOON...ENDING FROM WEST TO EAST AS FORCING
ALOFT WEAKENS. WEAK SURFACE RIDGING WILL QUICKLY TRACK ACROSS THE
REGION TUESDAY NIGHT BRINGING A BRIEF PERIOD OF CLEARING BEFORE
CLOUDS INCREASE IN ADVANCE OF ANOTHER APPROACHING WAVE ALOFT FROM
THE NORTHWEST.
THE UPPER WAVE WILL SWING ACROSS THE LOWER GREAT LAKES WEDNESDAY
WITH LIGHT SNOW SHOWERS IMPACTING PRIMARILY THE NORTHERN HALF OF THE
FORECAST AREA. COULD SEE SOME VERY LIGHT ACCUMS NORTH OF I-70 FROM A
DUSTING UP TO CLOSE TO AN INCH IN FAR NORTHERN COUNTIES BY LATE DAY
WEDNESDAY. BUMPED UP TO CHANCE POPS IN THE NORTH WEDNESDAY. SKIES
WILL CLEAR WEDNESDAY NIGHT AS HIGH PRESSURE REESTABLISHES ALONG WITH
A RENEWED SURGE OF COLDER AIR.
TEMPS...DEFINITELY THE BIG STORY OF THE SHORT TERM. UNDERCUT MOS
GUIDANCE FOR LOWS TONIGHT WITH SNOWCOVER AND 850MB TEMPS BOTTOMING
OUT AT -21 TO -20C BY TUESDAY MORNING. THINK MOST LOCATIONS GET INTO
THE SINGLE DIGITS. ONLY MODEST RECOVERY FOR TUESDAY AS HIGHS WILL
END UP RIGHT AROUND 20. LEANED CLOSER TO COOLER END OF GUIDANCE THE
REST OF THE WAY...WITH HIGHS RECOVERING INTO THE LOWER/MID 30S FOR
WEDNESDAY.
INDY RECORDS FOR TUESDAY...RECORD LOW IS 5 (1880) AND RECORD LOW MAX
TEMP IS 20 (1880). POTENTIAL FOR THE FIRST SINGLE DIGIT LOW IN
NOVEMBER SINCE 11/30/1976.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ISSUED AT 331 AM EST MON NOV 17 2014
ENSEMBLES SUGGEST A DEEP UPPER TROUGH INITIALLY OVER THE EASTERN
PARTS OF THE COUNTRY WILL BE LIFTING OFF TO THE NORTHEAST BY LATE IN
THE WEEK...LEAVING A MORE ZONAL FLOW OVER THE LOCAL AREA.
THE NEXT SYSTEM THAT MAY AFFECT THE AREA DURING THIS PERIOD WILL BE
A DISTURBANCE OF PACIFIC ORIGIN. THERE IS STILL QUITE A BIT OF
SPREAD AMONG THE ENSEMBLES AS TO THE TIMING OF THIS FEATURE...FROM
AS EARLY AS FRIDAY NIGHT TO AS LATE AS SATURDAY NIGHT OR SUNDAY. FOR
NOW...WILL BROADBRUSH POPS STARTING FRIDAY NIGHT THROUGH NEXT
SUNDAY. THERE MAY STILL BE ENOUGH RESIDUAL COLD AIR AROUND FOR MIXED
PRECIPITATION OVER PARTS OF THE AREA FRIDAY NIGHT THROUGH SATURDAY
NIGHT...BUT ENSEMBLES SUGGEST LITTLE THREAT FOR SIGNIFICANT
ACCUMULATIONS AT THIS TIME.
&&
.AVIATION /DISCUSSION FOR THE 171200Z TAFS/...
ISSUED AT 538 AM EST MON NOV 17 2014
BACK EDGE OF LOWER MVFR CEILINGS AROUND 012 CURRENTLY MOVING INTO
THE WESTERN BORDER ZONES. EXTRAPOLATION AND SHORT TERM MODELS
SUGGEST THESE LOWER CEILINGS WILL SCATTER OUT OVER THE TAF SITES BY
171400Z.
LOW LEVEL LAPSE RATES BECOME NEAR DRY ADIABATIC BY EARLY
AFTERNOON...SO EXPECTING VFR CEILINGS AROUND 040 TO DEVELOP BY THAT
TIME...AS WELL AS SCATTERED SNOW SHOWERS. MODEL GUIDANCE SUGGESTS
BRIEF IFR VISIBILITY RESTRICTIONS POSSIBLE IN THE HEAVIER
SHOWERS...BUT DUE TO THE SCATTERED NATURE OF THE SHOWERS...WILL
REFRAIN FROM AN EXPLICIT MENTION AT THIS TIME.
SURFACE WINDS EXPECTED TO GRADUALLY INCREASE AS THE MORNING GOES
BY...WITH GUSTS AROUND 25 KTS FROM 270-300 DEGREES EXPECTED BY THIS
AFTERNOON.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
INZ037>042-045>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1022 AM EST MON NOV 17 2014
.SYNOPSIS...
ISSUED AT 331 AM EST MON NOV 17 2014
LOW PRESSURE PASSING TO OUR NORTH TODAY...WILL USHER IN ANOTHER
SURGE OF COLD AIR. LAKE EFFECT SNOW SHOWERS WILL CONTINUE IN SOME
PLACES TODAY...BUT HEAVY SNOW IS EXPECTED TONIGHT AND TUESDAY IN
SOME OF THE CLASSIC SNOWBELTS. ANOTHER SYSTEM WILL BRING LIGHT SNOW
TO THE REGION WEDNESDAY...AND MORE LAKE EFFECT SNOW WILL FOLLOW
BEHIND IT. HOWEVER...TEMPERATURES WILL BECOME MILDER DURING THE
UPCOMING WEEKEND.
&&
.UPDATE...
ISSUED AT 1013 AM EST MON NOV 17 2014
THE FRONT IS MAKING ITS WAY FROM N LAKE MICHIGAN TO NW LOWER. THIS
HAS LEAD TO THE SW SNOW BANDS MERGING AND FLARING UP AS THEY MOVE
INLAND. THIS WILL LEAD TO TO BRIEFLY HEAVY SNOW AS THE BANDS
TRANSIT THE REGION OVER THE NEXT COUPLE OF HOURS. WILL EXPECT THAT
THE BANDS WILL LOSE THEIR INTENSITY AS THEY MOVE EAST AWAY FROM
THE LAKE.
BEHIND THE FRONT, THE SNOW BANDS ARE ALREADY REFORMING WITH THE
WEST WIND OVER THE N LAKE MICHIGAN. WILL BE EXPECTING THAT THE
SNOW BANDS WILL REESTABLISH QUICKLY, BUT THE WHETHER THEY WILL
REMAIN STATIONARY OR BE TRANSIENT OVER THE AFTERNOON IS UNCERTAIN
AS THE MODELS HAVE VARYING SOLUTIONS WITH A SPREAD OF ABOUT 30
DEGREES IN THE 1000-850 MB WIND DIRECTIONS. WILL CONTINUE THE
GOING AFTERNOON FORECAST UNTIL THE BANDS SHOW THEIR INTENTIONS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 331 AM EST MON NOV 17 2014
...SIGNIFICANT LAKE EFFECT SNOW EVENT EXPECTED LATER TODAY THROUGH
TUESDAY...
HIGH IMPACT WEATHER POTENTIAL: LOCALIZED VERY HEAVY LAKE EFFECT
SNOW. AREAS OF BLOWING SNOW AND NEAR WHITEOUT CONDITIONS POSSIBLE
TONIGHT.
PATTERN SYNOPSIS/CURRENT CONDITIONS: KINDA STATING THE OBVIOUS...BUT
MID-WINTER LIKE PATTERN WELL ESTABLISHED ACROSS THE NORTHERN LAKES.
REASON FOR SUCH IS ONE ANOMALOUSLY DEEP MERIDIONAL FLOW
REGIME...CONSISTING OF FULL LENGTH WESTERN NOAM RIDGING AND JUST AS
IMPRESSIVE TROUGHING EXTENDING THROUGH THE CENTRAL PLAINS INTO THE
WESTERN LAKES. MOST IMPRESSIVE COLD SURGE YET TIED TO WAVE OF ARCTIC
ORIGIN DIVING INTO SOUTHWEST ONTARIO AND INTO MINNESOTA (-20C H8
TEMPERATURES PER LATEST RAP ANALYSIS!). SURFACE COLD FRONT RUNNING
WELL AHEAD OF THIS WAVE...ALREADY PUSHING INTO NORTHWEST MICHIGAN AT
THIS EARLY HOUR. AREA OUT AHEAD OF THIS FRONT PLENTY COLD ENOUGH TO
CONTINUE TO ENTICE A SIGNIFICANT LAKE RESPONSE (A PRETTY RARE FEAT
TO HAVE SUCH COLD PRE-FRONTAL AIR DURING MID NOVEMBER). MAIN SHOW
TONIGHT HAS BEEN DIRECTED INTO PARTS OF EASTERN UPPER MICHIGAN..
WHERE NO DOUBT SEVERAL INCHES OF ACCUMULATION HAVE ALREADY OCCURRED.
SOMEWHAT LIGHTER MORE NUISANCE TYPE SNOWS IMPACTING NORTHER
LOWER...ALTHOUGH SOME EMBEDDED HEAVIER LAKE ENHANCED SNOWS WERE
NOTED...ESPECIALLY ACROSS PARTS OF EMMET COUNTY. SIMPLY NO END IN
SIGHT...WITH CURRENT UPSTREAM WAVE SET TO AMPLIFY OVERHEAD LATER
TODAY AND TONIGHT...FORCING A SHIFTING OF THE WINDS TO MORE W/NW AND
PUTTING THE MORE TRADITIONAL LAKE EFFECT AREAS UNDER THE GUN FOR A
HIGH IMPACT WINTER WEATHER EVENT.
PRIMARY FORECAST CONCERNS/CHALLENGES: MULTIPLE! INITIAL FOCUS ON
ONGOING SW FLOW LAKE EFFECT AND ASSOCIATED HEADLINES THIS MORNING.
OVERNIGHT FOCUS ON MUCH MORE WIDESPREAD LAKE SNOW EVENT...INCLUDING
AMOUNTS AND HEADLINE MANAGEMENT CONCERNS.
DETAILS: NOT PRETTY! FIRST OFF...ONGOING SW FLOW LAKE SNOWS SHOULD
STEADILY DECLINE IN INTENSITY SHORTLY AFTER 09Z AS WINDS BEGIN TO
SLOWLY VEER AND BRIEF CORRIDOR OF UPSTREAM DRIER AIR OVERSPEADS THE
LAKES. CURRENT HEADLINES RUN THROUGH 15Z...WHICH OFFERS SOME
FLEXIBILITY IF BANDS SHOULD PERSIST LONGER THAN ANTICIPATED (NEVER
SEEN THAN BEFORE :)). NO OFFICIAL REPORTS JUST YET...BUT BASED OFF
MACKINAC BRIDGE WEB CAMS AND SOME INFORMATION GLEANED FROM CALLING
ST. IGNACE...GOTTA FEELING WE WILL BE DEALING WITH SOME IMPRESSIVE
SNOWFALL TOTALS UP IN THE STRAITS AREA BEFORE ALL IS SAID AND DONE
THIS MORNING. ELSEWHERE...JUST SOME LIGHTER SNOWS EXPECTED AS THE
COLD FRONT PUSHES EAST...EXITING STAGE RIGHT BY MID-MORNING.
WITH PART ONE DONE...ALL FOCUS SHIFTS TO WHAT INCREASINGLY LOOKS
LIKE A VERY SIGNIFICANT AND PROLONGED LAKE EFFECT EVENT FOR THE MORE
TRADITIONAL SNOW BELTS OF EASTERN UPPER AND NORTHERN LOWER MICHIGAN.
CURRENT SOUTHWEST ONTARIO WAVE CONTINUES TO DIG...SLOWLY CROSSING
THE NORTHERN LAKES THROUGH THE OVERNIGHT. DESPITE MAIN CORE OF
ATTENDANT CAA ACTUALLY PASSING US BY TO THE SOUTH...INSTABILITY
RAMPS UP IMPRESSIVELY LATE TODAY THROUGH THE OVERNIGHT...WITH NEAR
EXTREME DELTA T/S COLLOCATED WITH DEEP SYNOPTIC MOISTURE SUPPORT AND
ESSENTIALLY ALL LOSS OF AN INVERSION. CYCLONIC FLOW IS IMPRESSIVE...
SUGGESTING ENHANCED CONVERGENCE TARGETING NORTHWEST LOWER MICHIGAN.
LOW LEVEL FLOW IS SLIGHTLY MORE BACKED IN RECENT GUIDANCE
RUNS...WELL SUPPORTED BY WHAT SHOULD BE STRENGTHENING LAKE DRIVEN
SURFACE TROUGH DEVELOPMENT. AFTER A BRIEF BREAK THIS AFTERNOON...
EXPECT SNOWS TO GET GOING IN EARNEST THIS EVENING...WITH INITIAL
FOCUS IN FAVORED WEST FLOW AREAS...WITH A SLIGHT SOUTHWARD TREND
EXPECTED DURING THE OVERNIGHT TOWARD THE M-32 CORRIDOR. SNOWFALL
AMOUNTS COULD BE QUITE IMPRESSIVE...WITH STRONG OMEGA CENTERED RIGHT
IN PRIME DGZ RIGHT THROUGH THE OVERNIGHT. DESPITE SOME FRAGMENTATION
OF FLAKES FROM VERY GUSTY WINDS (MORE ON THE WINDS TO
FOLLOW)...EXPECT SNOW TO LIQUID RATIOS TO PUSH 20 TO 1...PERHAPS
EVEN HIGHER IF STRONG LOW LEVEL CONVERGENCE UNDER BANDS HELP
SLACKING THE WIND FIELDS. SLIGHT SOUTHWARD DRIFT LOOKS TO BE THE
ONLY THING FROM PREVENTING SNOW AMOUNTS FROM GETTING TOO OUT OF
HAND. STILL...COULD EASILY SEE PARTS OF
CHARLEVOIX/ANTRIM/OTSEGO/EMMET/CHEBOYGAN COUNTIES EXCEEDING 8 INCHES
BY MORNING...WITH THE HIGHEST AMOUNTS JUST DOWNWIND OF LITTLE
TRAVERSE BAY. ANY SLOWER DRIFT OF BANDS THAN CURRENTLY ANTICIPATED
WILL RESULT IN LOCALLY HIGHER AMOUNTS. FURTHER SOUTH...COMPLETE LACK
OF A LAKE SUPERIOR CONNECTION REALLY SHORTENS THE EFFECTIVE FETCH
LENGTH. SO...DESPITE EXCELLENT INSTABILITY...JUST NOT SEEING THE
OPPORTUNITY FOR A WHOLE LOT OF ACCUMULATION ALONG AND SOUTH OF THE M-
72 CORRIDOR. HOWEVER...GUSTY WINDS OF 20 TO 30 MPH WILL MAKE FOR
SOME NASTY CONDITIONS...CREATING AREAS OF BLOWING AND DRIFTING SNOW
AND BRIEF PERIODS OF VERY LOW VISIBILITIES.
OFF LAKE SUPERIOR: INITIAL FOCUS THIS EVENING LOOKS TO REMAIN WEST
OF WHITEFISH POINT...REALLY TARGETING AREAS OVER NEAR MUNISING AND
SENEY. WINDS BEGIN TO SHIFT MORE W/NW LATE...BRINGING ACCUMULATING
SNOW BANDS INTO NORTHWEST CHIPPEWA COUNTY. LATER START AND SIGNALS
FOR BEST LOW LEVEL CONVERGENCE TO REMAIN OFF TO THE WEST SUGGESTS
LOWER SNOW TOTALS THAN THOSE TO THE SOUTH...WITH 2 TO 4 INCHES
EXPECTED BY MORNING. STRONG WINDS WILL PUSH BANDS FURTHER INLAND
THAN WHAT IS NORMAL...PERHAPS EVEN BRINGING PARTS OF NORTHWEST
MACKINAC COUNTY SEVERAL INCHES BY MORNING.
MORE SNOW WILL FALL IN ALL THE ABOVE AREAS TOMORROW...WITH SEVERAL
MORE INCHES EXPECTED (SEE LONG TERM SECTION BELOW).
HEADLINES: FOR NORTHERN LOWER...GIVEN GUSTY WINDS AND WHAT COULD BE
WIDESPREAD BLOWING SNOW EVEN OUTSIDE THE BETTER SNOW BANDS...HAVE
DECIDED TO FORGO THE SPECIFIC LAKE EFFECT HEADLINES FOR MORE GENERIC
WINTER WEATHER HEADLINES. HIGHEST SNOW TOTAL AREA MENTIONED EARLIER
WILL BE UPGRADED TO A WINTER STORM WARNING...STARTING AT 00Z THIS
EVENING RUNNING RIGHT THROUGH TUESDAY. WINTER WEATHER ADVISORIES
SHOULD DO FOR AREAS SOUTH OF M-72...AS WELL AS PARTS OF NORTHEAST
LOWER AS STRONG WINDS HELP PUSH WEAKENING BANDS FAR INLAND.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 331 AM EST MON NOV 17 2014
HIGH IMPACT WEATHER POTENTIAL...PLENTY OF SNOW AND COLD DURING THE
WORK WEEK. HEAVY LAKE EFFECT SNOW IN WNW/NW FLOW TUESDAY. SOME
POTENTIAL FOR HEAVY LAKE EFFECT SNOW WED NIGHT TO THU NIGHT.
TUESDAY...UPPER LOW WILL EJECT FROM NORTH OF LAKE HURON INTO EASTERN
QUEBEC. ONE TRAILING SHORTWAVE WILL CROSS CENTRAL LOWER MI IN THE
AFTERNOON...ANOTHER WEAK WAVE WILL DIG TOWARD EASTERN SUPERIOR. A
980MB SURFACE LOW STARTS THE MORNING IN CENTRAL QUEBEC...AND WILL
ADVANCE NE. SUBSTANTIAL TROFFING LINGERS ACROSS THE AREA EARLY IN
THE MORNING...THIS RELAXES AS THE UPPER LOW PULLS OUT...BUT LAKE-
INDUCED TROFFING REMAINS EVIDENT THRU THE DAY.
1000-850MB WINDS REMAIN STEADY-STATE IN THE MORNING...WNW INTO
NORTHERN LOWER AND NW INTO EASTERN UPPER. WINDS WILL BACK SOME
DURING THE AFTERNOON...BY EARLY EVENING WE WILL SEE A W FETCH INTO
NORTHERN LOWER AND WNW INTO EASTERN UPPER. PLENTY OF DEEP
MOISTURE...HIGH INVERSION HEIGHTS (TO NEARLY 500MB)...AND DELTA T/S
NEAR 20C SHOULD ENSURE RAMPAGING LAKE EFFECT SNOW IN THE MORNING
HOURS. IN THE AFTERNOON...THE INVERSION LOWERS TOWARD 700MB WITH
DRYING ALOFT. THAT WILL REDUCE SNOW INTENSITY SOMEWHAT...BUT BY AND
LARGE PARAMETERS AND STILL VERY FAVORABLE.
AS IS THE CASE FOR TONIGHT...THE LOW-LEVEL FLOW IS A LITTLE BACKED
COMPARED TO PREVIOUS RUNS. IN NORTHERN LOWER...THIS REQUIRES
ADJUSTING THE MAX SNOW TOTALS NORTHWARD SLIGHTLY.
CHARLEVOIX/ANTRIM/OTSEGO ARE THE MAIN ONES UNDER THE GUN...BUT THE
FETCH NOW SUPPORTS MORE SNOW IN SOUTHERN EMMET/CHEBOYGAN THAN IT
DOES IN NORTHERN KALKASKA/CRAWFORD. 5-9 INCHES STILL LIKES A GOOD
FORECAST FOR THE DAY IN THE HARDEST-HIT LOCALES...CENTERED ON
ELMIRA. 1-4 INCHES WORKS ELSEWHERE IN NW LOWER...WHERE THE FETCH IS
MUCH SHORTER AND HAS NO CONNECTION TO SUPERIOR.
IN EASTERN UPPER...THE BACKED FLOW OPENS UP MORE OF CHIPPEWA...BUT
SHOULD STILL KEEP THE STRONGEST BANDS WEST OF THE SAULT. BUT THINGS
ARE LOOKING CONSIDERABLY MORE FAVORABLE UP THERE...AND WILL INCREASE
WESTERN CHIP AND FAR NW MACK INTO THE 3-5 INCH RANGE.
MAX TEMPS WILL BE MAINLY IN THE 20S. HOWEVER...IN THE HIGH TERRAIN
IN THE SOUTH...WHERE MARINE MODIFICATION WILL BE SMALLER DUE TO THE
SHORTER FETCH...SOME PLACES (LIKE CAD) WILL LIKELY NOT ESCAPE THE
TEENS. (HARD TO BELIEVE IT/S ONLY MID-NOVEMBER.)
TUE NIGHT/WED...NOT MUCH REST FOR THE SNOW-WEARY. CLIPPER SHORTWAVE
WILL ADVANCE INTO THE WESTERN LAKES ON WED. ASSOCIATED SURFACE LOW
WILL ADVANCE FROM THE UPPER MS VALLEY TO NORTHERN LOWER MI ON WED.
LOW LEVEL FLOW WILL BACK TO THE SW TUE NIGHT...WITH MOISTENING
OVERNIGHT. SOME POTENTIAL FOR SOME SNEAKY 1-3 INCH ACCUMS OVER THE
TIP OF NORTHERN LOWER TUE EVENING. SYNOPTIC -SN MIGHT SNEAK INTO SW
SECTIONS LATE TUE NIGHT...BUT THE BULK OF THE THAT WILL WAIT UNTIL
WED. BY THEN...A SOUTH 1000-850MB FETCH SHOULD KEEP MOST OF THE LAKE-
INDUCED NONSENSE AT BAY...OTHER THAN ALONG THE SOUTH SHORE OF UPPER
MI (AND IT IS UNCERTAIN WHETHER SYNOPTIC PRECIP WILL MAKE IT THAT
FAR NORTH). THIS SYSTEM DOES NOT LOOK LIKE A MAJOR PROBLEM...1-2
INCHES...ESPECIALLY SOUTH OF M-32. MIN TEMPS TEENS TO PERHAPS HIGH
SINGLE DIGITS (YIKES). MAX TEMPS 20S.
REST OF THE FORECAST...POST-CLIPPER LAKE EFFECT SNOW WILL OCCUR WED
NIGHT INTO THU NIGHT...AIDED BY ANOTHER CLIPPER SHORTWAVE DROPPING
IN FROM THE NW. THE SET-UP FOR HEAVY SNOW LOOKS BETTER IN EASTERN
UPPER IN THIS EVENT...AS DEEPER MOISTURE WILL LINGER LONGER THERE VS
MID-LEVEL DRY AIR TRYING TO ENTRAIN INTO THE SOUTHER/CENTRAL LAKES.
REGARDLESS...LAKE EFFECT SHSN WILL AGAIN BE FAIRLY WIDESPREAD IN
BOTH PENINSULAS.
THOUGH THE MODELS TEND TO BE TOO FAST TO BREAK PATTERNS DOWN...ALL
MODELS HAVE THE CURRENT ONE FALL APART AFTER THIS LAST CLIPPER.
500MB FLOW BECOMES CONSIDERABLY MORE ZONAL...AND MORE SEASONABLE AIR
WILL FINALLY GET A CHANCE TO MOVE INTO THE REGION...ESPECIALLY BY
THE TAIL END OF THE WEEKEND. A SOUTHERN STREAM SYSTEM MOVING INTO
THE CENTRAL STATES WILL AMPLIFY WARM ADVECTION...AND INCREASE PRECIP
CHANCES BY SUNDAY. THIS ACTUALLY LOOKS TO BE MOSTLY RAIN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 632 AM EST MON NOV 17 2014
VFR TO MVFR AT APN...MVFR TO IFR ELSEWHERE IN LAKE EFFECT
CLOUDS/SHSN.
LOW PRESSURE ALONG THE NORTH SHORE OF SUPERIOR WILL MOVE EAST
TODAY...BRINGING ANOTHER SHOT OF COLD AIR TO THE REGION. LAKE
EFFECT SHSN TODAY WILL BECOME LESS ORGANIZED DUE TO VARYING WINDS
AND DRYING ALOFT. HOWEVER...SHSN WILL RAMP UP TONIGHT IN THE
SNOWBELTS OF FAR NORTHERN LOWER MICHIGAN...BETWEEN PLN AND GOV.
WILL HAVE VARYING CONDITIONS TODAY...TENDING TO MVFR NEAR LAKE MI
AND VFR AT APN. TONIGHT..LAKE MI TAF SITES WILL BE MAINLY IFR
(LIFR LATE AT PLN)...WHILE APN BECOMES MVFR.
WINDS WILL VEER W TODAY...STAY W AND INCREASE/BECOME GUSTY
TONIGHT.
&&
.MARINE...
ISSUED AT 331 AM EST MON NOV 17 2014
STRONG SURGE OF CAA AND INCREASINGLY SHARP PRESSURE
GRADIENT WILL BRING VERY GUSTY WINDS BY LATER TODAY RIGHT THROUGH
TUESDAY. GREATEST IMPACT EXPECTED ACROSS NORTHERN LAKE
MICHIGAN...WHERE GALE FORCE WEST WINDS ARE EXPECTED TO DEVELOP
QUICKLY THIS EVENING. SCA CONDITIONS EXPECTED ELSEWHERE...ALTHOUGH
WILL NEED TO BE ON THE LOOKOUT FOR SOME GALE GUSTS ALONG THE
NORTHEAST LOWER COASTLINE. WINDS ARE EXPECTED TO SUBSIDE LATE
TUESDAY...AND ESPECIALLY TUESDAY NIGHT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST
TUESDAY FOR MIZ018-020-023-025>028-031>033.
WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM EST TUESDAY
FOR MIZ016-017-019-021-022.
WINTER WEATHER ADVISORY FROM 1 AM TO 7 PM EST TUESDAY FOR MIZ008.
LH...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR LMZ341.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 7 PM EST TUESDAY FOR
LMZ323-342-344>346.
LS...SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING TO 7 PM EST TUESDAY
FOR LSZ321-322.
&&
$$
UPDATE...JSL
SYNOPSIS...JAZ
SHORT TERM...MSB
LONG TERM...JAZ
AVIATION...JAZ
MARINE...MSB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
647 AM EST MON NOV 17 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 411 AM EST MON NOV 17 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS INDICATE A DEEPENING
UPR TROF OVER CENTRAL NAMERICA WITH CLOSED H5 LO OVER ONTARIO JUST
NW OF LK SUP CAUSING 12HR H5 HGT FALLS UP TO 130M BTWN 16/12Z AND
17/00Z AT INL AND DRAWING H5 TEMPS CLOSE TO -40C S UNDER THE AXIS OF
LOWEST HGTS. BAND OF DPVA/DEEP LYR QVECTOR CNVGC/AXIS OF MID LVL
MSTR IN ADVANCE OF SHRTWV ROTATING ARND THE CLOSED LO IS CROSSING
UPR MI EARLY THIS MRNG...BUT DRYNESS OF AIRMASS SHOWN ON THE 00Z GRB
RAOB /PWAT 0.16 INCH IS 45 PCT OF NORMAL/ IS GREATLY LIMITING THE
COVERAGE/INTENSITY OF ACCOMPANYING LIGHT SN. THERE HAS BEEN SOME
LIGHT SN OVER THE FAR E NEAR NEWBERRY WITH A SW WIND OFF NRN LK
MI...BUT THE FLOW HAS NOT BACKED SUFFICIENTLY TO CAUSE THE HEAVIER
SN SHOWERS IN MACKINAC COUNTY TO IMPACT LUCE/SCHOOLCRAFT COUNTIES.
LOOKING TO THE W...THE 00Z H85/7 TEMPS WERE -17C/-27C AT INL /VS
-14C AND -16C AT GRB/. THE 00Z INL IS QUITE MOIST ALMOST UP TO H5
WITHIN A DEEP CYC FLOW. THERE IS A SHARP SFC WSHFT FM W TO NW ALONG
A SFC LO PRES TROF RUNNING THRU NRN MN INTO ADJACENT ONTARIO...WITH
SFC REPORTS SHOWING SOME MODERATE SN ALONG AND JUST BEHIND THIS
BNDRY.
MAIN FOCUS IN THE SHORT TERM WL BE ON LES AMOUNTS/GOING HEADLINES
ASSOCIATED WITH INCOMING COLD/MOIST AIRMASS. MADE NO CHANGES ATTM TO
HEADLINES ISSUED BY THE PREVIOUS SHIFT.
TODAY...AS CUTOFF H5 LO DEEPENS FURTHER AND SLIDES SLOWLY TO THE E
ACROSS UPR MI...SHARP CYC LLVL FLOW IS FCST TO SLOWLY ENVELOP THE
CWA W-E WITH A WSHFT FM WSW EARLY THIS MRNG TO NW BY LATE IN THE DAY
EXCEPT OVER THE SE CWA. THE SHARPER LLVL CNVGC WL ARRIVE OVER THE W
ARND 12Z AND RESULT IN INCRSG SN RATES DESPITE SOME DEEP LYR QVECTOR
DVGC IN THE WAKE OF THE SHRTWV ROTATING THRU THE UPR LKS EARLY THIS
MRNG. THE HIER RES MODELS HAVE CONSISTENTLY POINTED TO THE AREA ARND
ONTONAGON COUNTY AS THE FOCUS FOR THE SHARPEST CNVGC. GOING START
TIME OF 12Z FOR THE WARNINGS OVER THE W APPEARS TO BE ON TRACK.
SINCE THE RATHER LO UVV MAX IN THE ABSENCE OF DEEP LYR FORCING WL BE
CENTERED IN THE DGZ...EXPECT GOOD SN/WATER RATIOS IN EXCESS OF 20:1
DESPITE A DGZ DEPTH OF ONLY ABOUT 3K FT AND INCRSG WINDS THAT WOULD
TEND TO FRAGMENT THE SN FLAKES. WITH SOME INCRSG DEEP LYR QVECTOR
CNVGC/UVV OVER THE W HALF LATER IN THE DAY UNDER THE DEEPENING UPR
TROF AXIS...FCST SDNGS ALSO INDICATE INCRSG DEEP MSTR THRU THE DAY
PER THE 00Z INL RAOB WITH EQUILIBRIUM LVLS APRCHG 10K FT OVER THE BY
LATER IN THE DAY AS H85/7 TEMPS DIP TO -16C TO -17C/-27C. INCRSG NW
WINDS/DESTABILIZATION WL RESULT IN GUSTY SFC WINDS AND SOME BLSN AS
WELL. FARTHER TO THE E...THE LLVL FLOW IS FCST TO BE OUT OF THE W
MOST OF THE DAY...SO THE SN SHOWERS THERE SHOULD BE MAINLY CONFINED
TO THE LK SHORE UNTIL AT LEAST 21Z...WHEN THE FASTER HI RES CNDN
MODEL SHOWS THE ARRIVAL OF SHARPER CYC FLOW/ WSHFT TO THE NW. FCST
LES WARNINGS FOR ALGER/NRN SCHOOLCRAFT COUNTIES BEGINS AT 21Z...SO
WL NOT CHANGE THIS START TIME. THERE SHOULD BE NOTHING MORE THAN
FLURRIES/LIGHT SN SHOWERS OVER THE SCENTRAL WITH DOWNSLOPE FLOW.
TNGT...UPR TROF/AXIS OF DEEP LYR QVECTOR CNVGC AND MSTR/SFC LO PRES
TROF AND CYC WSHFT TO THE NW ARE PROGGED TO DRIFT SLOWLY E. THESE
TRENDS WL RESULT IN INCRSG POPS/SN RATES IN THE NW SN BELTS MAINLY E
OF MARQUETTE. THE 00Z NAM AND ESPECIALLY THE HI RES CNDN MODEL HINT
LK NIPIGON MOISTENING WL GREATLY ENHANCE SN RATES OVER ALGER/NRN
SCHOOLCRAFT COUNTIES...SO THE GOING WRNGS APPEAR ON TRACK. AS WL BE
THE CASE TODAY OVER THE W...HI EQUILIBRIUM LVL AND FAVORABLE UVV MAX
WITHIN THE DGZ WL BE ENHANCING FACTORS FOR SN RATES IN THIS AREA.
ALTHOUGH THE DEPARTURE OF THE DYANAMIC SUPPORT/VERY DEEP MSTR MAY
SLOW DOWN THE HEAVY SN RATES OVER THE W BY THE OVERNGT HRS...
LINGERING CYC NW BACKING TOWARD THE WNW OVER THE FAR W TOWARD 12Z WL
CONTINUE WIDESPREAD SN SHOWERS/CATEGORICAL POPS IN THE FAVORED SN
BELTS THERE. ALTHOUGH THE EXPECTED NW FLOW IS NOT FAVORABLE FOR
MARQUETTE COUNTY...WL CONTINUE THE ADVY FOR THIS AREA GIVEN
POTENTIAL FOR HIER WINDS NEAR THE LK SHORE AND HEAVIER SN IN THE
EASTERN PART OF THE COUNTY. ONCE AGAIN...THE LIGHTEST AND LEAST
WIDESPREAD SN SHOWERS WL BE OVER THE SCENTRAL.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 646 AM EST MON NOV 17 2014
UPPER TROUGH THAT IS IN THE PROCESS OF MOVING OVER THE AREA TODAY
WILL BE STARTING TO MOVE OUT OF THE AREA WHILE A WEAK SURFACE RIDGE
OVER THE NORTHERN PLAINS SHIFTS EAST INTO THE UPPER GREAT LAKES
REGION. MODERATE TO HEAVY SNOW WILL BE ONGOING OVER PORTIONS OF THE
CWA...ESPECIALLY OVER THE EAST (ALGER AND NORTHERN SCHOOLCRAFT
COUNTIES) WHERE THE NORTHWEST FLOW LAKE EFFECT WILL BE AIDED BY LOW
LEVEL WINDS STARTING TO BACK IN RESPONSE TO THE SURFACE RIDGE AND
INCREASING CONVERGENCE. EXPECT THE FAVORABLE CONDITIONS TO CONTINUE
THROUGH THE MORNING OVER THE EAST...BEFORE THE DRYING AND LOWERING
INVERSION HEIGHTS SEEN OVER THE WEST DURING THE MORNING...MOVES
INTO THE AREA AND DIMINISHES THE INTENSITY OF THE LAKE EFFECT.
WINDS WILL ALSO BE STEADILY BACKING THROUGH THE DAY...TO THE
SOUTHWEST OVER THE WESTERN CWA AND WESTERLY OVER THE EASTERN CWA BY
THE EVENING HOURS TUESDAY. THUS...WOULD EXPECT TRANSIENT BANDS
BECOMING FOCUSED OVER THE KEWEENAW PENINSULA AND NEAR LAKE SUPERIOR
EAST OF PICTURED ROCKS. AS FOR SNOWFALL ACCUMULATION...HAVE ANOTHER
3-5 INCHES NORTHWEST OF A LINE FROM DEERTON TO MANISTIQUE AND
ANOTHER 1-3 INCHES OVER THE TRADITIONAL AREAS OVER THE WEST.
TUESDAY EVENING...COULD SEE ANOTHER 1-2 INCHES AS THE LAKE EFFECT
TRANSITIONS NORTH ACROSS THE KEWEENAW PENINSULA BEFORE IT MOVES
OFFSHORE.
ALSO ON TUESDAY NIGHT...A SHORTWAVE WILL DIVE SOUTHEAST FROM
CENTRAL CANADA...THROUGH NORTHERN MINNESOTA AND INTO WISCONSIN. AT
THE SURFACE...A BROAD TROUGH WILL QUICKLY DROP INTO THE AREA AND
BRING MORE VARIABLE LOW LEVEL WINDS TO THE AREA. WILL CONTINUE TO
SHOW SLIGHT AND LOW CHANCE POPS FOR AREAS NEAR THE WISCONSIN BORDER
LATE TUESDAY NIGHT. THIS COULD CONTINUE INTO WEDNESDAY FOR MUCH OF
THE AREA AS BROAD MID LEVEL Q-VECTOR CONVERGENCE CONTINUES ALTHOUGH
MUCH OF THE AREA WILL BE BETWEEN THE INITIAL SHORTWAVE MOVING INTO
LOWER MICHIGAN AND THE SECONDARY SHORTWAVE DROPPING INTO NORTHWEST
WISCONSIN LATE WEDNESDAY AFTERNOON. THUS...WILL SHOW SOME POTENTIAL
FOR LIGHT SNOW SHOWERS ON WEDNESDAY. ALSO ON WEDNESDAY...COULD SEE
LAKE EFFECT OFF LAKE MICHIGAN OVER SOUTHEAST LUCE COUNTY ON
WEDNESDAY AFTERNOON AS LOW LEVEL WINDS BACK FAR ENOUGH TO THE
SOUTH-SOUTHWEST TO PUSH THE BAND INTO THAT AREA. THEN AS WINDS SHIFT
TO THE WEST-NORTHWEST BEHIND A SECONDARY SURFACE TROUGH...EXPECT THE
LAKE EFFECT SNOW TO PICKUP IN THE KEWEENAW FIRST (WEDNESDAY
AFTERNOON) AND THEN SPREAD OVER THE REST OF THE NORMAL
WEST-NORTHWEST FAVORED LOCATIONS OVER THE WEST DURING THE EVENING
AND EAST OVERNIGHT. WINDS ON THURSDAY WILL DEPEND ON THE TRAILING
SURFACE TROUGH ATTEMPTING TO HOLD OVER EASTERN LAKE SUPERIOR. MODELS
VARY ON ITS LOCATION LATE WEDNESDAY NIGHT INTO THURSDAY AND HOW
QUICKLY IT DEPARTS. DUE TO THESE DIFFERENCES...THE FINER DETAILS ARE
HARD TO PIN DOWN AND WILL FOCUS ON GENERAL NORTHWEST WIND LAKE
EFFECT FOR THE TIME BEING. STILL EXPECT VERY FAVORABLE LAKE EFFECT
CONDITIONS (DELTA-T VALUES AROUND 23) BUT LAKE INDUCED EQUILIBRIUM
VALUES WILL BE 5KFT LOWER THAN TONIGHT (UP TO 13KFT) AND LAKE
INDUCED CAPE VALUES WILL PEAK AROUND 800 J/KG. WINDS DO LOOK TO BE
WEAKER DURING THIS PERIOD...WHICH WOULD LEAD TO LESS FRACTURING OF
THE DENDRITES...BUT DO HAVE A LITTLE CONCERN THAT THE TOP HALF OF
THE CLOUD WILL BE ABOVE THE DGZ AND SUPPORT MORE COLUMNS IN THE SNOW
AND LEAD TO LOWER RATIOS. THUS...WILL STICK WITH SNOW RATIOS AROUND
OR JUST ABOVE 20-1 AT THIS POINT AND WILL BE ABLE TO FINE TUNE WITH
FUTURE SHIFTS. THIS PRODUCES SNOWFALL AMOUNTS OF 5 TO 11 INCHES IN
THE NORTHWEST TO WEST-NORTHWEST WIND SNOW BELTS FOR WEDNESDAY
AFTERNOON INTO THURSDAY EVENING. CURRENT THINKING IS A GENERAL LES
ADVISORY WILL BE NEEDED AT SOME POINT (UNLESS INCREASED CONVERGENCE
OCCURS ALONG THE TRAILING SURFACE TROUGH) AND WILL CONTINUE TO
HIGHLIGHT IN THE HWO/EHWO.
UPPER TROUGH WILL BEGIN TO SHIFT EAST AND OUT OF THE AREA ON
THURSDAY...ALLOWING AN UPPER RIDGE TO BUILD TOWARDS THE AREA
THURSDAY NIGHT AND IN TURN A SURFACE RIDGE. THIS WILL GRADUALLY
WEAKEN THE LAKE EFFECT ON THURSDAY NIGHT INTO FRIDAY AS INVERSION
HEIGHTS STEADILY FALL AND WINDS BACK TO THE WEST AND EVENTUALLY
SOUTHWEST. THE HIGH PRESSURE RIDGE WILL CONTINUE EAST ON FRIDAY
NIGHT...AS THE CENTER OF THE HIGH MOVES INTO THE MID ATLANTIC
STATES. WITH THE MORE ZONAL FLOW ALOFT...EXPECT TEMPERATURES TO
BEGIN TO MODERATE HEADING INTO THE WEEKEND BUT STILL BE BELOW
NORMAL FOR THIS TIME OF YEAR. MODELS STILL DON/T HAVE MUCH
CONSISTENCY FOR THIS WEEKEND...AS THEY AREA STRUGGLING WITH THE
TIMING/LOCATION OF THE INITIAL SHORTWAVE EJECTING NORTHEAST OUT OF
THE UPPER TROUGH OVER THE ROCKIES. THUS...WILL FOLLOW A GENERAL
MODEL CONSENSUS AND BRING SLIGHT CHANCE POPS INTO THE AREA FOR
SATURDAY NIGHT AND CHANCE ON SUNDAY. WITH THE WARM AIR WRAPPING
NORTHWARD...DID GO WITH MAINLY RAIN ON SUNDAY OVER THE EASTERN U.P.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 646 AM EST MON NOV 17 2014
THE COMBINATION OF INCRSG DEEP MSTR AND AN APRCHG LO PRES TROF WL
BRING HEAVIER LAKE EFFECT SN TO CMX AND IWD...WITH CONDITIONS AT
THOSE SITES DETERIORATING TO IFR THIS MRNG. AS CYC NW WINDS BECOME
QUITE GUSTY FOLLOWING THE PASSAGE OF THE TROF...EXPECT CONSIDERABLE
BLSN TO REDUCE VSBYS INTO THE LIFR RANGE AT IWD AND CMX FOR THE REST
OF THE FCST PERIOD. THE STRONGEST WINDS WITH GUSTS NEAR 30KTS WL
IMPACT THE MORE EXPOSED CMX LOCATION. SINCE THE FLOW WL BE A
DOWNSLOPE W WIND AT SAW THRU THIS MRNG...VFR CONDITIONS WL
PREDOMINATE THERE UNTIL THE ARRIVAL OF DEEPER MSTR AND THE TROF
LATER THIS AFTN. IFR TO AT TIMES MVFR VSBYS WL THEN BE THE RULE
UNTIL LATE TNGT...WHEN THE DEEPER MSTR WL BEGIN TO DIMINISH AND
CONDITIONS IMPROVE TO MVFR/PERHAPS VFR WITH DOWNSLOPE WIND COMPONENT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 646 AM EST MON NOV 17 2014
LOW PRESSURE OVER FAR NORTHERN LAKE SUPERIOR WILL SHIFT EAST
TODAY...SWEEPING A SURFACE TROUGH SOUTHEAST ACROSS LAKE SUPERIOR
TODAY. BEHIND THE TROUGH...LOOK FOR GUSTS TO INCREASE TO GALES OF
35-40KTS OVER PORTIONS OF W LAKE SUPERIOR THIS AFTERNOON...BEFORE
EXPANDING TO THE E HALF OF LAKE SUPERIOR THIS EVENING THROUGH
EARLY TUESDAY. THE TIMING OF THE GALE WARNING WAS IN GOOD SHAPE
AND WILL CONTINUE. A TROUGH WILL THEN LINGER ACROSS LAKE SUPERIOR
THROUGH TUESDAY MORNING...BEFORE BRIEFLY BEING REPLACED BY A RIDGE
TUESDAY AFTERNOON AND EVENING. ANOTHER TROUGH OVER N MANITOBA ON
TUESDAY WILL SLIDE ACROSS THE UPPER GREAT LAKES LATE TUESDAY NIGHT
THROUGH WEDNESDAY...BEFORE EXITING ACROSS THE ONTARIO AND QUEBEC
BORDER THURSDAY MORNING. A FEW NORTHWEST GALE FORCE GUSTS TO 35
KNOTS ARE POSSIBLE OVER EASTERN LAKE SUPERIOR LATE WEDNESDAY
NIGHT INTO THURSDAY MORNING. HIGH PRESSURE OVER THE N PLAINS ON
THURSDAY WILL DIVE ACROSS THE OHIO VALLEY LATE FRIDAY...EXTENDING A
RIDGE OVER THE UPPER GREAT LAKES ON FRIDAY AND DIMINISHING WINDS
BELOW 25 KNOTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST TUESDAY FOR MIZ004-084.
LAKE EFFECT SNOW WARNING FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR MIZ006-085.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST /NOON CST/ TUESDAY FOR
MIZ001>003-009.
LAKE EFFECT SNOW ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR MIZ007.
LAKE EFFECT SNOW ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM EST
TUESDAY FOR MIZ005.
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 1 PM EST
TUESDAY FOR MIZ014.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TO 1 PM EST TUESDAY FOR LSZ251-267.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 1 PM EST TUESDAY FOR
LSZ248>250-265-266.
GALE WARNING FROM 1 PM THIS AFTERNOON TO 9 AM EST TUESDAY FOR
LSZ264.
GALE WARNING FROM 1 PM EST /NOON CST/ THIS AFTERNOON TO 4 AM EST
/3 AM CST/ TUESDAY FOR LSZ240>242-263.
GALE WARNING FROM 1 PM THIS AFTERNOON TO 7 AM EST TUESDAY FOR
LSZ243>245.
GALE WARNING FROM 1 PM EST /NOON CST/ THIS AFTERNOON TO 1 AM EST
/MIDNIGHT CST/ TUESDAY FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GAYLORD MI
632 AM EST MON NOV 17 2014
.SYNOPSIS...
ISSUED AT 331 AM EST MON NOV 17 2014
LOW PRESSURE PASSING TO OUR NORTH TODAY...WILL USHER IN ANOTHER
SURGE OF COLD AIR. LAKE EFFECT SNOW SHOWERS WILL CONTINUE IN SOME
PLACES TODAY...BUT HEAVY SNOW IS EXPECTED TONIGHT AND TUESDAY IN
SOME OF THE CLASSIC SNOWBELTS. ANOTHER SYSTEM WILL BRING LIGHT SNOW
TO THE REGION WEDNESDAY...AND MORE LAKE EFFECT SNOW WILL FOLLOW
BEHIND IT. HOWEVER...TEMPERATURES WILL BECOME MILDER DURING THE
UPCOMING WEEKEND.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 331 AM EST MON NOV 17 2014
...SIGNIFICANT LAKE EFFECT SNOW EVENT EXPECTED LATER TODAY THROUGH
TUESDAY...
HIGH IMPACT WEATHER POTENTIAL: LOCALIZED VERY HEAVY LAKE EFFECT
SNOW. AREAS OF BLOWING SNOW AND NEAR WHITEOUT CONDITIONS POSSIBLE
TONIGHT.
PATTERN SYNOPSIS/CURRENT CONDITIONS: KINDA STATING THE OBVIOUS...BUT
MID-WINTER LIKE PATTERN WELL ESTABLISHED ACROSS THE NORTHERN LAKES.
REASON FOR SUCH IS ONE ANOMALOUSLY DEEP MERIDIONAL FLOW
REGIME...CONSISTING OF FULL LENGTH WESTERN NOAM RIDGING AND JUST AS
IMPRESSIVE TROUGHING EXTENDING THROUGH THE CENTRAL PLAINS INTO THE
WESTERN LAKES. MOST IMPRESSIVE COLD SURGE YET TIED TO WAVE OF ARCTIC
ORIGIN DIVING INTO SOUTHWEST ONTARIO AND INTO MINNESOTA (-20C H8
TEMPERATURES PER LATEST RAP ANALYSIS!). SURFACE COLD FRONT RUNNING
WELL AHEAD OF THIS WAVE...ALREADY PUSHING INTO NORTHWEST MICHIGAN AT
THIS EARLY HOUR. AREA OUT AHEAD OF THIS FRONT PLENTY COLD ENOUGH TO
CONTINUE TO ENTICE A SIGNIFICANT LAKE RESPONSE (A PRETTY RARE FEAT
TO HAVE SUCH COLD PRE-FRONTAL AIR DURING MID NOVEMBER). MAIN SHOW
TONIGHT HAS BEEN DIRECTED INTO PARTS OF EASTERN UPPER MICHIGAN..
WHERE NO DOUBT SEVERAL INCHES OF ACCUMULATION HAVE ALREADY OCCURRED.
SOMEWHAT LIGHTER MORE NUISANCE TYPE SNOWS IMPACTING NORTHER
LOWER...ALTHOUGH SOME EMBEDDED HEAVIER LAKE ENHANCED SNOWS WERE
NOTED...ESPECIALLY ACROSS PARTS OF EMMET COUNTY. SIMPLY NO END IN
SIGHT...WITH CURRENT UPSTREAM WAVE SET TO AMPLIFY OVERHEAD LATER
TODAY AND TONIGHT...FORCING A SHIFTING OF THE WINDS TO MORE W/NW AND
PUTTING THE MORE TRADITIONAL LAKE EFFECT AREAS UNDER THE GUN FOR A
HIGH IMPACT WINTER WEATHER EVENT.
PRIMARY FORECAST CONCERNS/CHALLENGES: MULTIPLE! INITIAL FOCUS ON
ONGOING SW FLOW LAKE EFFECT AND ASSOCIATED HEADLINES THIS MORNING.
OVERNIGHT FOCUS ON MUCH MORE WIDESPREAD LAKE SNOW EVENT...INCLUDING
AMOUNTS AND HEADLINE MANAGEMENT CONCERNS.
DETAILS: NOT PRETTY! FIRST OFF...ONGOING SW FLOW LAKE SNOWS SHOULD
STEADILY DECLINE IN INTENSITY SHORTLY AFTER 09Z AS WINDS BEGIN TO
SLOWLY VEER AND BRIEF CORRIDOR OF UPSTREAM DRIER AIR OVERSPEADS THE
LAKES. CURRENT HEADLINES RUN THROUGH 15Z...WHICH OFFERS SOME
FLEXIBILITY IF BANDS SHOULD PERSIST LONGER THAN ANTICIPATED (NEVER
SEEN THAN BEFORE :)). NO OFFICIAL REPORTS JUST YET...BUT BASED OFF
MACKINAC BRIDGE WEB CAMS AND SOME INFORMATION GLEANED FROM CALLING
ST. IGNACE...GOTTA FEELING WE WILL BE DEALING WITH SOME IMPRESSIVE
SNOWFALL TOTALS UP IN THE STRAITS AREA BEFORE ALL IS SAID AND DONE
THIS MORNING. ELSEWHERE...JUST SOME LIGHTER SNOWS EXPECTED AS THE
COLD FRONT PUSHES EAST...EXITING STAGE RIGHT BY MID-MORNING.
WITH PART ONE DONE...ALL FOCUS SHIFTS TO WHAT INCREASINGLY LOOKS
LIKE A VERY SIGNIFICANT AND PROLONGED LAKE EFFECT EVENT FOR THE MORE
TRADITIONAL SNOW BELTS OF EASTERN UPPER AND NORTHERN LOWER MICHIGAN.
CURRENT SOUTHWEST ONTARIO WAVE CONTINUES TO DIG...SLOWLY CROSSING
THE NORTHERN LAKES THROUGH THE OVERNIGHT. DESPITE MAIN CORE OF
ATTENDANT CAA ACTUALLY PASSING US BY TO THE SOUTH...INSTABILITY
RAMPS UP IMPRESSIVELY LATE TODAY THROUGH THE OVERNIGHT...WITH NEAR
EXTREME DELTA T/S COLLOCATED WITH DEEP SYNOPTIC MOISTURE SUPPORT AND
ESSENTIALLY ALL LOSS OF AN INVERSION. CYCLONIC FLOW IS IMPRESSIVE...
SUGGESTING ENHANCED CONVERGENCE TARGETING NORTHWEST LOWER MICHIGAN.
LOW LEVEL FLOW IS SLIGHTLY MORE BACKED IN RECENT GUIDANCE
RUNS...WELL SUPPORTED BY WHAT SHOULD BE STRENGTHENING LAKE DRIVEN
SURFACE TROUGH DEVELOPMENT. AFTER A BRIEF BREAK THIS AFTERNOON...
EXPECT SNOWS TO GET GOING IN EARNEST THIS EVENING...WITH INITIAL
FOCUS IN FAVORED WEST FLOW AREAS...WITH A SLIGHT SOUTHWARD TREND
EXPECTED DURING THE OVERNIGHT TOWARD THE M-32 CORRIDOR. SNOWFALL
AMOUNTS COULD BE QUITE IMPRESSIVE...WITH STRONG OMEGA CENTERED RIGHT
IN PRIME DGZ RIGHT THROUGH THE OVERNIGHT. DESPITE SOME FRAGMENTATION
OF FLAKES FROM VERY GUSTY WINDS (MORE ON THE WINDS TO
FOLLOW)...EXPECT SNOW TO LIQUID RATIOS TO PUSH 20 TO 1...PERHAPS
EVEN HIGHER IF STRONG LOW LEVEL CONVERGENCE UNDER BANDS HELP
SLACKING THE WIND FIELDS. SLIGHT SOUTHWARD DRIFT LOOKS TO BE THE
ONLY THING FROM PREVENTING SNOW AMOUNTS FROM GETTING TOO OUT OF
HAND. STILL...COULD EASILY SEE PARTS OF
CHARLEVOIX/ANTRIM/OTSEGO/EMMET/CHEBOYGAN COUNTIES EXCEEDING 8 INCHES
BY MORNING...WITH THE HIGHEST AMOUNTS JUST DOWNWIND OF LITTLE
TRAVERSE BAY. ANY SLOWER DRIFT OF BANDS THAN CURRENTLY ANTICIPATED
WILL RESULT IN LOCALLY HIGHER AMOUNTS. FURTHER SOUTH...COMPLETE LACK
OF A LAKE SUPERIOR CONNECTION REALLY SHORTENS THE EFFECTIVE FETCH
LENGTH. SO...DESPITE EXCELLENT INSTABILITY...JUST NOT SEEING THE
OPPORTUNITY FOR A WHOLE LOT OF ACCUMULATION ALONG AND SOUTH OF THE M-
72 CORRIDOR. HOWEVER...GUSTY WINDS OF 20 TO 30 MPH WILL MAKE FOR
SOME NASTY CONDITIONS...CREATING AREAS OF BLOWING AND DRIFTING SNOW
AND BRIEF PERIODS OF VERY LOW VISIBILITIES.
OFF LAKE SUPERIOR: INITIAL FOCUS THIS EVENING LOOKS TO REMAIN WEST
OF WHITEFISH POINT...REALLY TARGETING AREAS OVER NEAR MUNISING AND
SENEY. WINDS BEGIN TO SHIFT MORE W/NW LATE...BRINGING ACCUMULATING
SNOW BANDS INTO NORTHWEST CHIPPEWA COUNTY. LATER START AND SIGNALS
FOR BEST LOW LEVEL CONVERGENCE TO REMAIN OFF TO THE WEST SUGGESTS
LOWER SNOW TOTALS THAN THOSE TO THE SOUTH...WITH 2 TO 4 INCHES
EXPECTED BY MORNING. STRONG WINDS WILL PUSH BANDS FURTHER INLAND
THAN WHAT IS NORMAL...PERHAPS EVEN BRINGING PARTS OF NORTHWEST
MACKINAC COUNTY SEVERAL INCHES BY MORNING.
MORE SNOW WILL FALL IN ALL THE ABOVE AREAS TOMORROW...WITH SEVERAL
MORE INCHES EXPECTED (SEE LONG TERM SECTION BELOW).
HEADLINES: FOR NORTHERN LOWER...GIVEN GUSTY WINDS AND WHAT COULD BE
WIDESPREAD BLOWING SNOW EVEN OUTSIDE THE BETTER SNOW BANDS...HAVE
DECIDED TO FORGO THE SPECIFIC LAKE EFFECT HEADLINES FOR MORE GENERIC
WINTER WEATHER HEADLINES. HIGHEST SNOW TOTAL AREA MENTIONED EARLIER
WILL BE UPGRADED TO A WINTER STORM WARNING...STARTING AT 00Z THIS
EVENING RUNNING RIGHT THROUGH TUESDAY. WINTER WEATHER ADVISORIES
SHOULD DO FOR AREAS SOUTH OF M-72...AS WELL AS PARTS OF NORTHEAST
LOWER AS STRONG WINDS HELP PUSH WEAKENING BANDS FAR INLAND.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 331 AM EST MON NOV 17 2014
HIGH IMPACT WEATHER POTENTIAL...PLENTY OF SNOW AND COLD DURING THE
WORK WEEK. HEAVY LAKE EFFECT SNOW IN WNW/NW FLOW TUESDAY. SOME
POTENTIAL FOR HEAVY LAKE EFFECT SNOW WED NIGHT TO THU NIGHT.
TUESDAY...UPPER LOW WILL EJECT FROM NORTH OF LAKE HURON INTO EASTERN
QUEBEC. ONE TRAILING SHORTWAVE WILL CROSS CENTRAL LOWER MI IN THE
AFTERNOON...ANOTHER WEAK WAVE WILL DIG TOWARD EASTERN SUPERIOR. A
980MB SURFACE LOW STARTS THE MORNING IN CENTRAL QUEBEC...AND WILL
ADVANCE NE. SUBSTANTIAL TROFFING LINGERS ACROSS THE AREA EARLY IN
THE MORNING...THIS RELAXES AS THE UPPER LOW PULLS OUT...BUT LAKE-
INDUCED TROFFING REMAINS EVIDENT THRU THE DAY.
1000-850MB WINDS REMAIN STEADY-STATE IN THE MORNING...WNW INTO
NORTHERN LOWER AND NW INTO EASTERN UPPER. WINDS WILL BACK SOME
DURING THE AFTERNOON...BY EARLY EVENING WE WILL SEE A W FETCH INTO
NORTHERN LOWER AND WNW INTO EASTERN UPPER. PLENTY OF DEEP
MOISTURE...HIGH INVERSION HEIGHTS (TO NEARLY 500MB)...AND DELTA T/S
NEAR 20C SHOULD ENSURE RAMPAGING LAKE EFFECT SNOW IN THE MORNING
HOURS. IN THE AFTERNOON...THE INVERSION LOWERS TOWARD 700MB WITH
DRYING ALOFT. THAT WILL REDUCE SNOW INTENSITY SOMEWHAT...BUT BY AND
LARGE PARAMETERS AND STILL VERY FAVORABLE.
AS IS THE CASE FOR TONIGHT...THE LOW-LEVEL FLOW IS A LITTLE BACKED
COMPARED TO PREVIOUS RUNS. IN NORTHERN LOWER...THIS REQUIRES
ADJUSTING THE MAX SNOW TOTALS NORTHWARD SLIGHTLY.
CHARLEVOIX/ANTRIM/OTSEGO ARE THE MAIN ONES UNDER THE GUN...BUT THE
FETCH NOW SUPPORTS MORE SNOW IN SOUTHERN EMMET/CHEBOYGAN THAN IT
DOES IN NORTHERN KALKASKA/CRAWFORD. 5-9 INCHES STILL LIKES A GOOD
FORECAST FOR THE DAY IN THE HARDEST-HIT LOCALES...CENTERED ON
ELMIRA. 1-4 INCHES WORKS ELSEWHERE IN NW LOWER...WHERE THE FETCH IS
MUCH SHORTER AND HAS NO CONNECTION TO SUPERIOR.
IN EASTERN UPPER...THE BACKED FLOW OPENS UP MORE OF CHIPPEWA...BUT
SHOULD STILL KEEP THE STRONGEST BANDS WEST OF THE SAULT. BUT THINGS
ARE LOOKING CONSIDERABLY MORE FAVORABLE UP THERE...AND WILL INCREASE
WESTERN CHIP AND FAR NW MACK INTO THE 3-5 INCH RANGE.
MAX TEMPS WILL BE MAINLY IN THE 20S. HOWEVER...IN THE HIGH TERRAIN
IN THE SOUTH...WHERE MARINE MODIFICATION WILL BE SMALLER DUE TO THE
SHORTER FETCH...SOME PLACES (LIKE CAD) WILL LIKELY NOT ESCAPE THE
TEENS. (HARD TO BELIEVE IT/S ONLY MID-NOVEMBER.)
TUE NIGHT/WED...NOT MUCH REST FOR THE SNOW-WEARY. CLIPPER SHORTWAVE
WILL ADVANCE INTO THE WESTERN LAKES ON WED. ASSOCIATED SURFACE LOW
WILL ADVANCE FROM THE UPPER MS VALLEY TO NORTHERN LOWER MI ON WED.
LOW LEVEL FLOW WILL BACK TO THE SW TUE NIGHT...WITH MOISTENING
OVERNIGHT. SOME POTENTIAL FOR SOME SNEAKY 1-3 INCH ACCUMS OVER THE
TIP OF NORTHERN LOWER TUE EVENING. SYNOPTIC -SN MIGHT SNEAK INTO SW
SECTIONS LATE TUE NIGHT...BUT THE BULK OF THE THAT WILL WAIT UNTIL
WED. BY THEN...A SOUTH 1000-850MB FETCH SHOULD KEEP MOST OF THE LAKE-
INDUCED NONSENSE AT BAY...OTHER THAN ALONG THE SOUTH SHORE OF UPPER
MI (AND IT IS UNCERTAIN WHETHER SYNOPTIC PRECIP WILL MAKE IT THAT
FAR NORTH). THIS SYSTEM DOES NOT LOOK LIKE A MAJOR PROBLEM...1-2
INCHES...ESPECIALLY SOUTH OF M-32. MIN TEMPS TEENS TO PERHAPS HIGH
SINGLE DIGITS (YIKES). MAX TEMPS 20S.
REST OF THE FORECAST...POST-CLIPPER LAKE EFFECT SNOW WILL OCCUR WED
NIGHT INTO THU NIGHT...AIDED BY ANOTHER CLIPPER SHORTWAVE DROPPING
IN FROM THE NW. THE SET-UP FOR HEAVY SNOW LOOKS BETTER IN EASTERN
UPPER IN THIS EVENT...AS DEEPER MOISTURE WILL LINGER LONGER THERE VS
MID-LEVEL DRY AIR TRYING TO ENTRAIN INTO THE SOUTHER/CENTRAL LAKES.
REGARDLESS...LAKE EFFECT SHSN WILL AGAIN BE FAIRLY WIDESPREAD IN
BOTH PENINSULAS.
THOUGH THE MODELS TEND TO BE TOO FAST TO BREAK PATTERNS DOWN...ALL
MODELS HAVE THE CURRENT ONE FALL APART AFTER THIS LAST CLIPPER.
500MB FLOW BECOMES CONSIDERABLY MORE ZONAL...AND MORE SEASONABLE AIR
WILL FINALLY GET A CHANCE TO MOVE INTO THE REGION...ESPECIALLY BY
THE TAIL END OF THE WEEKEND. A SOUTHERN STREAM SYSTEM MOVING INTO
THE CENTRAL STATES WILL AMPLIFY WARM ADVECTION...AND INCREASE PRECIP
CHANCES BY SUNDAY. THIS ACTUALLY LOOKS TO BE MOSTLY RAIN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 632 AM EST MON NOV 17 2014
VFR TO MVFR AT APN...MVFR TO IFR ELSEWHERE IN LAKE EFFECT
CLOUDS/SHSN.
LOW PRESSURE ALONG THE NORTH SHORE OF SUPERIOR WILL MOVE EAST
TODAY...BRINGING ANOTHER SHOT OF COLD AIR TO THE REGION. LAKE
EFFECT SHSN TODAY WILL BECOME LESS ORGANIZED DUE TO VARYING WINDS
AND DRYING ALOFT. HOWEVER...SHSN WILL RAMP UP TONIGHT IN THE
SNOWBELTS OF FAR NORTHERN LOWER MICHIGAN...BETWEEN PLN AND GOV.
WILL HAVE VARYING CONDITIONS TODAY...TENDING TO MVFR NEAR LAKE MI
AND VFR AT APN. TONIGHT..LAKE MI TAF SITES WILL BE MAINLY IFR
(LIFR LATE AT PLN)...WHILE APN BECOMES MVFR.
WINDS WILL VEER W TODAY...STAY W AND INCREASE/BECOME GUSTY
TONIGHT.
&&
.MARINE...
ISSUED AT 331 AM EST MON NOV 17 2014
STRONG SURGE OF CAA AND INCREASINGLY SHARP PRESSURE
GRADIENT WILL BRING VERY GUSTY WINDS BY LATER TODAY RIGHT THROUGH
TUESDAY. GREATEST IMPACT EXPECTED ACROSS NORTHERN LAKE
MICHIGAN...WHERE GALE FORCE WEST WINDS ARE EXPECTED TO DEVELOP
QUICKLY THIS EVENING. SCA CONDITIONS EXPECTED ELSEWHERE...ALTHOUGH
WILL NEED TO BE ON THE LOOKOUT FOR SOME GALE GUSTS ALONG THE
NORTHEAST LOWER COASTLINE. WINDS ARE EXPECTED TO SUBSIDE LATE
TUESDAY...AND ESPECIALLY TUESDAY NIGHT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST
TUESDAY FOR MIZ018-020-023-025>028-031>033.
WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM EST TUESDAY
FOR MIZ016-017-019-021-022.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MIZ008-016.
WINTER WEATHER ADVISORY FROM 1 AM TO 7 PM EST TUESDAY FOR MIZ008.
LAKE EFFECT SNOW WARNING UNTIL 10 AM EST THIS MORNING FOR MIZ015.
LH...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR LMZ341.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 7 PM EST TUESDAY FOR
LMZ323-342-344>346.
LS...SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING TO 7 PM EST TUESDAY
FOR LSZ321-322.
&&
$$
SYNOPSIS...JAZ
SHORT TERM...MSB
LONG TERM...JAZ
AVIATION...JAZ
MARINE...MSB
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
958 AM EST MON NOV 17 2014
.SYNOPSIS...
A COMPLEX LOW PRESSURE SYSTEM AND ASSOCIATED FRONTS WILL MOVE
ACROSS THE NORTH COUNTRY TODAY. PRECIPITATION WILL START OUT AS
SNOW...CHANGE TO A MIX...THEN RAIN BEFORE ENDING. A SIGNIFICANT
LAKE EFFECT SNOW EVENT IS EXPECTED FOR THE NORTHERN ADIRONDACKS
AND THE SOUTHERN SAINT LAWRENCE VALLEY EARLY THIS WEEK.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 958 AM EST MONDAY...MINOR UPDATES HERE AT MID MORNING.
RADAR SHOWING LOTS OF PRECIPITATION ACROSS THE REGION, THOUGH
THERE IS A SLIGHT LULL ACROSS MUCH OF NORTHERN VERMONT. SURFACE
TEMPERATURES IN MOST LOWER ELEVATION AREAS ARE IN THE 32-36F
RANGE, SO ROADS SEEM TO BE IN DECENT SHAPE. STILL 22-24F UP ON
MANSFIELD AND WHITEFACE, SO THE NOSE OF WARMER AIR ALOFT IS STILL
NOT THAT FAR NORTH, SO SNOW IS STILL THE MAIN P-TYPE ABOVE ROUGHLY
800FT ELEVATION. BELOW THAT, IT`S RAIN/SNOW OR ALREADY TURNED OVER
TO RAIN. CAN`T RULE OUT A TOUCH OF FREEZING DRIZZLE EITHER,
ESPECIALLY IN SOUTHERN SECTIONS OF VERMONT. ASOS IN SPRINGFIELD
HAS RECORDED 0.02" OF ICING.
FORECAST ISSUE IS TRYING TO TIME THE VARIOUS P-TYPE CHANGEOVER
TIMES. HAVE RELIED HEAVILY ON THE 13Z RAP FOR GUIDANCE FOR
TEMPERATURES ALOFT. 12Z ALBANY SOUNDING SHOWED THE ABOVE-FREEZING
AIR BETWEEN 800-700MB (5000-8000FT) AND THIS WAS PUSHING
NORTHWARD. BASED UPON THE RAP, THAT WARMER AIR SHOULD REACH THE
CANADIAN BORDER ABOUT 20Z. BY THAT POINT, PRETTY MUCH ALL OF US
WILL BE SEEING LIGHT RAIN, THOUGH THE LOWER ELEVATIONS SUCH AS THE
CHAMPLAIN VALLEY SHOULD BE ALL RAIN BY 16Z (11AM).
LOOKING UPSTREAM, WE STILL HAVE SOME PRECIPITATION TO MOVE
THROUGH, THOUGH NOTHING LOOKS TOO TERRIBLY HEAVY. PERHAPS
0.04"/HOUR AT BEST. ADD THAT UP OVER THE AFTERNOON, AND WE ARE
LOOKING AT PERHAPS 1/4" OF LIQUID EQUIVALENT. COMBINE THAT WITH
WHEN IT WILL ACTUALLY BE IN THE FORM OF SNOW, WE AREN`T LOOKING AT
MUCH ACCUMULATION - ANOTHER 1/2" IN THE HIGHER ELEVATIONS.
I JUST WANT TO SEE HOW THINGS PLAY OUT OVER THE NEXT FEW HOURS,
AND ASSUMING MOTHER NATURE FOLLOWS OUR EXPECTATIONS, I WOULD THINK
WE SHOULD BE ABLE TO TAKE DOWN THE WINTER WEATHER ADVISORY FOR THE
`DACKS EARLY (JUST LEAVING THE LAKE EFFECT WARNING IN PLACE).
&&
.SHORT TERM /7 PM THIS EVENING THROUGH WEDNESDAY/...
AS OF 400 AM EST MONDAY...THIS EVENING COLD AIR STREAMS BACK INTO
THE AREA FROM THE WEST AND ANY PRECIPITATION REMAINING WILL CHANGE
TO SNOW SHOWERS FROM WEST TO EAST ACROSS OUR FORECAST AREA. AS
COLD AIR MOVES IN...STRONG FLOW ACROSS MILD LAKE ONTARIO WILL
CREATE PERSISTENT BAND OF LAKE EFFECT SNOW IN THE SOUTHERN SAINT
LAWRENCE VALLEY AND NORTHERN ADIRONDACKS. HAVE UPGRADED OUR LAKE
EFFECT SNOW WATCH TO A WARNING...ALSO MOVED UP THE START TIME TO
00Z TUESDAY...ENDING 12Z WEDNESDAY. STRONG AND UNIFORM SSW FLOW OF
40+ KNOTS SHOULD SUSTAIN SIGNIFICANT BAND OF LAKE EFFECT. THERE IS
ALSO PLENTY OF LOW LEVEL INSTABILITY TO SUSTAIN THIS. ANALOGS
INDICATE THAT THIS COULD BE A MAJOR LAKE EFFECT SNOW EVENT
DOWNWIND OF LAKE ONTARIO. A SOUTHWEST FLOW SINGLE BAND LAKE EFFECT
SNOW EVENT IS EXPECTED. UPPER TROF CROSSING OUR AREA DURING THIS
TIME INFLUENCES FLOW AND SET UP OF THE SNOW BAND. SURFACE WINDS
WILL ALSO BE STRONG WITH INCREASED PRESSURE GRADIENT...MAKING
CONDITIONS EVEN WORSE WHERE THE HEAVY SNOW IS FALLING. THUNDER AND
LIGHTNING WILL BE POSSIBLE WITH LAKE EFFECT SNOW DUE TO HIGH
CAPE...AND HEAVY RAINFALL RATES ARE POSSIBLE WITH THE WELL ALIGNED
FLOW AND TEMPERATURE CONTRAST. LAKE EFFECT SNOW WILL TEMPORARILY
SHUT DOWN WEDNESDAY AFTERNOON WITH THE UPPER TROF PASSING AND FLOW
BECOMING MORE SOUTHERLY. ADDITIONAL LAKE EFFECT SNOW IS EXPECTED
LATER IN THE WEEK. TEMPERATURES WILL BE COLD FROM TONIGHT THROUGH
WEDNESDAY...ABOUT 10 TO 15 DEGREES BELOW SEASONAL NORMALS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 320 AM EST SUNDAY...THIS MORNING`S GLOBAL MODELS REMAIN IN
GOOD AGREEMENT SHOWING PRIMARY SURGE OF CP AIR TO AFFECT THE
NORTHEAST DURING THE THU-SAT TIME FRAME WITH DAILY TEMPERATURES
AVERAGING SOME 12 TO 18 DEGREES BELOW LATE AUTUMN NORMS.
THEREAFTER INCREASING SIGNS THAT A SIGNIFICANT WARM-UP WILL SPREAD
EAST ACROSS THE CENTRAL/ERN U.S. BY LATER NEXT WEEKEND INTO EARLY
NEXT WEEK AS STRONG BELT OF WESTERLIES UNDERCUT THE DEPARTING
ARCTIC AIRMASS.
DETAILS...IN THE LATE WEEK TIME FRAME WILL STILL BE DEALING WITH
COLD TEMPERATURES AND PERSISTENT LAKE EFFECT SNOWS DOWNWIND OF
LAKE ONTARIO. FINAL BUT FAIRLY SHARP ARCTIC SHORTWAVE TROUGH AND
ASSOCIATED FRONTAL PASSAGE WILL CROSS THE AREA THURSDAY INTO
THURSDAY NIGHT WITH LAKE SNOWS SHIFTING SLOWLY N-S OVER TIME WITH
ADDITIONAL...POTENTIALLY SIGNIFICANT ACCUMULATIONS ACROSS THE
SNOWBELTS THU/EARLY FRI. ELSEWHERE SCT FLURRIES/SHSN STILL A GOOD
BET...ESP IN THE NRN GREENS ON THU WHERE SOME ADDITIONAL MINOR
ACCUMULATIONS WILL ALSO BE POSSIBLE. HIGHS GENERALLY RUNNING FROM
25 TO 35 ON THURSDAY...THEN COLDER IN THE 20S BEHIND THE FRONT
FRI. LOWS MAINLY IN THE TEENS/20S THU...THEN TEENS BY FRI.
BY SATURDAY ARCTIC HIGH PRESSURE SETTLES ACROSS THE EAST COAST AS
LAKE SNOWS COME TO AND END AND SKIES TREND CLR/PTLY CLOUDY. STILL
UNSEASONABLY CHILLY WITH MORNING LOWS SINGLE DIGITS/TEENS AND
HIGHS REMAINING IN THE 20S DESPITE THE INCREASING SUN.
THEREAFTER THERE IS INCREASING CONFIDENCE THAT A MAJOR PATTERN
CHANGE WILL OCCUR ACROSS THE NORTHEAST BY LATER NEXT WEEKEND AND
BEYOND AS ARCTIC AIR LIFTS OUT TO THE NORTHEAST AND IS REPLACED BY
INCREASINGLY MILD WEST/SOUTHWEST CONUS FLOW. THUS HAVE ADVERTISED
TEMPERATURES CLIMBING BACK ABOVE THE FREEZING MARK (30S) IN ALL
AREAS BY NEXT SUNDAY WITH EVEN MILDER AIR ON THE HORIZON FOR EARLY
NEXT WEEK AS CHANCES FOR RAIN SLOWLY INCREASE.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
THROUGH 12Z TUESDAY...MIVFR/IFR CONDITIONS IN SNOW THIS MORNING
AS LOW PRESSURE LIFTS ACROSS THE AREA WITH WIDESPREAD PCPN. PCPN
CHANGING TO A MIX THEN PLAIN RAIN SOUTH TO NORTH FOR KPBG AND VT
TERMINALS FROM 14-18Z. SNOW HANGS ON LONGER IN THE COLDER AIR AT
KMSS/KSLK AND MAY REMAIN ALL SNOW AT KMSS DEPENDING ON DEGREE OF
WARMER AIR ALOFT. PCPN TAPERS OFF BY 00Z LEAVING GENERALLY BKN/OVC
MVFR/VFR CIGS. EXCEPTION AT KSLK WHERE PERSISTENT MVFR/IFR SHSN
WILL CONTINUE. WINDS GENERALLY SOUTH/SOUTHEASTERLY 5 TO 10 KTS
TODAY (NORTHEASTERLY AT KMSS)...VEERING TO SOUTHWESTERLY 8 TO 15
KTS AND BECOMING GUSTY AFTER 00Z AS SFC FRONT CLEARS EAST.
OUTLOOK 12Z TUESDAY THROUGH FRIDAY...
12Z TUESDAY ONWARD...SCT/BKN MAINLY VFR WITH INTERMITTENT SNOW
SHOWERS/FLURRIES AND BRIEF PERIODS OF MVFR/IFR POSSIBLE. EXCEPTION
AT KSLK WHERE INFLUENCE OF LAKE ONTARIO LAKE EFFECT SNOWS WILL
COME INTO PLAY WITH MVFR AND OCCNL IFR SHSN MORE PREVALENT.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...LAKE EFFECT SNOW WARNING FROM 7 PM THIS EVENING TO 7 AM EST
WEDNESDAY FOR NYZ029-030-087.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ029>031-034.
&&
$$
SYNOPSIS...NEILES
NEAR TERM...NASH
SHORT TERM...NEILES/SISSON
LONG TERM...JMG
AVIATION...JMG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
837 AM CST MON NOV 17 2014
.UPDATE...
ISSUED AT 837 AM CST MON NOV 17 2014
NO MAJOR CHANGES WERE MADE TO THE ONGOING FORECAST. ONLY ADJUSTED
THE HOURLY SENSIBLE WEATHER GRIDS TO COME MORE IN LINE WITH THE
CURRENT OBS/TRENDS. THE UPDATED PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 644 AM CST MON NOV 17 2014
NO SIGNIFICANT CHANGES REQUIRED WITH THIS FORECAST UPDATE OTHER
THAN TO BLEND TO OBSERVED TRENDS THROUGH 12 UTC WITH A FRIGID DAY
EXPECTED AREA WIDE IN THE WAKE OF THE SUNDAY REINFORCING COLD
FRONT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 334 AM CST MON NOV 17 2014
HUDSON BAY UPPER LOW WITH SUCCESSIVE SHORTWAVE TROUGHS ROTATING
AROUND HAS CARVED OUT A SIGNIFICANT UPPER TROUGH EXTENDING SOUTH
INTO THE MIDWEST AND SOUTHERN PLAINS PER LATEST WATER VAPOR
IMAGERY. NORTHERLY FLOW INTO NORTH DAKOTA WITH ANOTHER MINOR
SHORTWAVE NOW LOCATED JUST WEST OF LAKE WINNIPEG IS FORECAST TO
REACH INTO THE BISMARCK VICINITY BY 18Z TODAY. THE LATEST
FOG/STRATUS LOOP SHOWS CLOUDS AND FLURRIES OVER THE
SOUTHWEST...WHICH EXTENDS ACROSS MOST OF EASTERN MONTANA. FARTHER
UPSTREAM CLOSER TO THE LOCATION OF THE INCOMING SHORTWAVE...QUITE
A BIT OF CLOUDS PUSHING SOUTH. THE LATEST HRRR REINFORCES CLOUDS
ESPECIALLY IN THE WEST...BUT THINK THE CENTRAL WILL ALSO CLOUD UP
DURING THE LATE MORNING AND EARLY AFTERNOON. THE HIGH RESOLUTION
ARW AND NMM MODELS CONTINUE WITH THE FLURRIES WEST THROUGH 18Z
TODAY AND HAVE FOLLOWED THIS AS THEY ARE VERIFYING THE BEST EARLY
THIS MORNING WITH THE CURRENT ACTIVITY. WARM AIR ADVECTION
COMMENCES MONDAY NIGHT WITH A PUSH OF H7-H5 MOISTURE. THIS WILL
PROGRESS FROM WEST TO EAST OVERNIGHT RESULTING IN PARTLY CLOUDY
CONDITIONS. HIGHS TODAY WILL RANGE FROM 10F TO 15F WITH OVERNIGHT
LOWS BETWEEN 3 BELOW ZERO TO 3 ABOVE.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 334 AM CST MON NOV 17 2014
A POTENTIAL MODERATION IN TEMPERATURES LATE THIS WEEK HIGHLIGHTS
THE EXTENDED FORECAST.
THE 00 UTC SUITE IS IN AGREEMENT ON THE ANOMALOUS HIGH AMPLITUDE
UPPER LEVEL PATTERN ACROSS NORTH AMERICA BREAKING DOWN TO A NEAR
ZONAL PATTERN BY NEXT WEEKEND IN A BROAD VERY LOW AMPLITUDE
TROUGH. THIS WOULD SIGNAL A RECOVERY FROM THE ARCTIC TEMPERATURES
TO STILL BELOW NORMAL...YET MORE TOLERABLE HIGHS NEAR FREEZING
FRIDAY INTO THE WEEKEND. THE EXTENDED FORECAST LOOKS TO BE LARGELY
PRECIPITATION FREE...WITH SPLIT FLOW DEVELOPING AND THE LACK OF
MOISTURE RECOVERY FROM THE ARCTIC AIRMASS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 645 AM CST MON NOV 17 2014
CIGS WILL TRANSITION FROM LOW VFR AT KISN/KDIK TO MVFR BETWEEN
15Z-16Z...WITH IMPROVING CONDITIONS TO VFR BY 00Z TUESDAY. ISOLATED
FLURRIES ARE POSSIBLE AT KDIK AND KISN THIS MORNING WITH MINIMAL
VISIBILITY IMPACTS. LOW VFR CIGS EXPECTED AT KMOT/KBIS/KJMS
THROUGH THE PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
645 AM CST MON NOV 17 2014
.UPDATE...
ISSUED AT 644 AM CST MON NOV 17 2014
NO SIGNIFICANT CHANGES REQUIRED WITH THIS FORECAST UPDATE OTHER
THAN TO BLEND TO OBSERVED TRENDS THROUGH 12 UTC WITH A FRIGID DAY
EXPECTED AREA WIDE IN THE WAKE OF THE SUNDAY REINFORCING COLD
FRONT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 334 AM CST MON NOV 17 2014
HUDSON BAY UPPER LOW WITH SUCCESSIVE SHORTWAVE TROUGHS ROTATING
AROUND HAS CARVED OUT A SIGNIFICANT UPPER TROUGH EXTENDING SOUTH
INTO THE MIDWEST AND SOUTHERN PLAINS PER LATEST WATER VAPOR
IMAGERY. NORTHERLY FLOW INTO NORTH DAKOTA WITH ANOTHER MINOR
SHORTWAVE NOW LOCATED JUST WEST OF LAKE WINNIPEG IS FORECAST TO
REACH INTO THE BISMARCK VICINITY BY 18Z TODAY. THE LATEST
FOG/STRATUS LOOP SHOWS CLOUDS AND FLURRIES OVER THE
SOUTHWEST...WHICH EXTENDS ACROSS MOST OF EASTERN MONTANA. FARTHER
UPSTREAM CLOSER TO THE LOCATION OF THE INCOMING SHORTWAVE...QUITE
A BIT OF CLOUDS PUSHING SOUTH. THE LATEST HRRR REINFORCES CLOUDS
ESPECIALLY IN THE WEST...BUT THINK THE CENTRAL WILL ALSO CLOUD UP
DURING THE LATE MORNING AND EARLY AFTERNOON. THE HIGH RESOLUTION
ARW AND NMM MODELS CONTINUE WITH THE FLURRIES WEST THROUGH 18Z
TODAY AND HAVE FOLLOWED THIS AS THEY ARE VERIFYING THE BEST EARLY
THIS MORNING WITH THE CURRENT ACTIVITY. WARM AIR ADVECTION
COMMENCES MONDAY NIGHT WITH A PUSH OF H7-H5 MOISTURE. THIS WILL
PROGRESS FROM WEST TO EAST OVERNIGHT RESULTING IN PARTLY CLOUDY
CONDITIONS. HIGHS TODAY WILL RANGE FROM 10F TO 15F WITH OVERNIGHT
LOWS BETWEEN 3 BELOW ZERO TO 3 ABOVE.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 334 AM CST MON NOV 17 2014
A POTENTIAL MODERATION IN TEMPERATURES LATE THIS WEEK HIGHLIGHTS
THE EXTENDED FORECAST.
THE 00 UTC SUITE IS IN AGREEMENT ON THE ANOMALOUS HIGH AMPLITUDE
UPPER LEVEL PATTERN ACROSS NORTH AMERICA BREAKING DOWN TO A NEAR
ZONAL PATTERN BY NEXT WEEKEND IN A BROAD VERY LOW AMPLITUDE
TROUGH. THIS WOULD SIGNAL A RECOVERY FROM THE ARCTIC TEMPERATURES
TO STILL BELOW NORMAL...YET MORE TOLERABLE HIGHS NEAR FREEZING
FRIDAY INTO THE WEEKEND. THE EXTENDED FORECAST LOOKS TO BE LARGELY
PRECIPITATION FREE...WITH SPLIT FLOW DEVELOPING AND THE LACK OF
MOISTURE RECOVERY FROM THE ARCTIC AIRMASS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 645 AM CST MON NOV 17 2014
CIGS WILL TRANSITION FROM LOW VFR AT KISN/KDIK TO MVFR BETWEEN
15Z-16Z...WITH IMPROVING CONDITIONS TO VFR BY 00Z TUESDAY. ISOLATED
FLURRIES ARE POSSIBLE AT KDIK AND KISN THIS MORNING WITH MINIMAL
VISIBILITY IMPACTS. LOW VFR CIGS EXPECTED AT KMOT/KBIS/KJMS
THROUGH THE PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
920 AM EST MON NOV 17 2014
.SYNOPSIS...
A STORM SYSTEM WILL MOVE EAST OF THE REGION TODAY. ARCTIC AIR WILL
FOLLOW IN THE WAKE OF THE STORM...BRINGING VERY COLD CONDITIONS
THROUGH TUESDAY NIGHT. A COLD FRONT WILL PUSH THROUGH THE AREA
WEDNESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MORNING UPDATE CENTERED ON PULLING THE BACK EDGE OF SNOW FURTHER
WEST WHERE IT IS CURRENTLY RIGHT ON WESTERN CWA EDGE. IT WILL BLOW
THROUGH PRETTY QUICK THIS LATE MORNING AND I WAS ABLE TO KEEP THE
18Z SNOW FORECAST THE SAME - GENERALLY DRY OVER CWA WITH SOME
LINGERING LIGHT STUFF IN THE SCIOTO VALLEY AND HOCKING HILLS.
TEMPS AND DEWPOINTS WERE RUNNING ON WITH CURRENT FORECAST. PREV
DISC BELOW
PRECIPITATION CONTINUES ACROSS ALMOST THE ENTIRE FORECAST AREA
EARLY THIS MORNING. CORRELATION COEFFICIENT ON KILN RADAR
INDICATES THAT THE RAIN-SNOW LINE EXTENDS FROM ROBERTSON COUNTY
NORTHEAST TO HOCKING COUNTY. THIS TRANSITION WILL CONTINUE TO
PUSH EAST THROUGH THE MORNING SO THAT ALL AREAS WILL SEE SNOW
BEFORE THE PRECIPITATION COMES TO AN END.
LATEST HRRR AND RAP RUNS SUGGEST THAT THERE MAY BE A TEMPORARY
LULL IN PRECIPITATION OVER THE NEXT FEW HOURS WITH ONE MORE SURGE
AFTER 12Z. THIS LAST ROUND OF PRECIPITATION WILL QUICKLY MOVE OFF
TO THE EAST OF THE AREA BETWEEN 15Z AND 18Z.
WARM GROUND SEEMS TO BE DOING QUITE A JOB IN LIMITING ACCUMULATIONS
THUS FAR. THIS IS EVEN MORE SO ON PAVEMENT. A MAJORITY OF ROAD
TEMPERATURE SENSORS ACROSS THE FORECAST AREA ARE STILL ABOVE
FREEZING BUT ROADS ARE STARTING TO GET COVERED. AND AS SNOW
CONTINUES AND GROUND TEMPERATURES FALL IN TANDEM WITH COLDER AIR
TEMPERATURES FILTERING IN...SLIPPERY CONDITIONS WILL OCCUR ON
AREA ROADS.
BASED ON ACCUMULATIONS SEEN THUS FAR HAVE PULLED BACK SLIGHTLY ON
STORM TOTAL AMOUNTS. WARNING AREA IS MARGINAL AT THIS POINT BUT
WILL KEEP IT GOING FOR NOW WITH ADDITIONAL SNOW COMING. ADVISORY
AREA REMAINS UNCHANGED.
HIGH TEMPERATURES WILL BE REALIZED EARLY THIS MORNING WITH
READINGS FALLING AS ARCTIC AIR SURGES INTO THE REGION. WEST WINDS
WILL BECOME GUSTY AND FLURRIES WILL LIKELY DEVELOP IN THE
AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
ARCTIC AIR WILL CONTINUE TO POUR INTO THE AREA TONIGHT AND
TUESDAY. THIS WILL KEEP GUSTY WINDS GOING. LOW CLOUDS SHOULD
PERSIST. CLOUD COVER SHOULD BE ENOUGH TO KEEP LOWS JUST ABOVE
RECORD BUT RECORD LOW HIGHS ON TUESDAY ARE A NEAR CERTAINTY.
FLURRIES WILL CONTINUE FROM TIME TO TIME.
FLOW WILL TURN AROUND TO THE SOUTH TUESDAY NIGHT AHEAD OF THE NEXT
SYSTEM BUT TEMPERATURES WILL REMAIN VERY COLD. READINGS WILL
REBOUND RELATIVELY SPEAKING ON WEDNESDAY. HOWEVER A COLD FRONT
WILL PUSH TOWARDS THE REGION AND THEN MOVE THROUGH WEDNESDAY
NIGHT. APPEARS THAT SCATTERED SNOW SHOWERS MAY OCCUR WITH THE
BOUNDARY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
FOR THURSDAY THROUGH FRIDAY...MODELS ARE SOMEWHAT DIFFERENT IN
REGARDS TO THE AMOUNT OF RESURGING ARCTIC AIR THAT WILL BLEED BACK
INTO OUR AREA IN ASSOCIATION WITH SFC HIGH PRESSURE. IT SHOULD BE
DRY...BUT TEMPERATURES WILL STILL BE WELL BELOW NORMAL.
MODELS KEEP ADVERTISING A PATTERN SHIFT FOR THE UPCOMING WEEKEND AS
THE LONGWAVE PATTERN WILL PUSH ARCTIC AIR BACK NORTH INTO CANADA
WHILE A SERIES OF WEATHER SYSTEMS MOVING INTO THE REGION WILL BE OF
A PACIFIC ORIGIN. THERE ARE SOME TIMING ISSUES BUT IT APPEARS THAT
RETURN FLOW/WAA PATTERN ALONG WITH A WEATHER SYSTEM WILL BRING AN
INCREASING THREAT FOR SHOWERS SATURDAY NIGHT INTO SUNDAY.
TEMPERATURES BY SUNDAY ARE FORECAST TO APPROACH NORMAL HIGHS IN THE
MID 40S TO AROUND 50 DEGREES.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
HEAVIEST BURST OF SNOW PULLING THROUGH MOST TAF LOCATIONS AT THIS
TIME WITH IFR CIGS AND VSBYS TO CONTINUE THROUGH 14-15Z. SLOW
IMPROVEMENT THROUGH THE DAY OF VSBYS WITH VFR EXPECTED ONCE MAIN
BAND OF SNOW PULLS OUT...THOUGH LOW MVFR CIGS TO REMAIN THROUGH
MUCH OF THE DAY. FLURRIES AND SPOTTY SNOW SHOWERS THIS AFTERNOON
WILL BRING A CHANCE FOR MVFR VSBYS THROUGH 00Z...THEN VFR CIGS
AFTER ABOUT 05Z.
OUTLOOK...SNOW SQUALLS ON TUESDAY COULD YIELD MVFR/IFR CONDITIONS
AT TIMES.
&&
.CLIMATE...
RECORD LOWS FOR TUESDAY MORNING NOVEMBER 18
CVG...12 DEGREES...1880
CMH...10 DEGREES...1880
DAY...13 DEGREES...1959
RECORD LOW MAX TEMPERATURES ON NOVEMBER 18
CVG...26 DEGREES...1951
CMH...26 DEGREES...1903
DAY...27 DEGREES...1951 AND 1903
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR OHZ026-034-
035-042>045-051>054-060>062.
WINTER STORM WARNING UNTIL NOON EST TODAY FOR OHZ063-064-
070>072-077>080.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
OHZ046-055-056-065-073-074-081-082.
KY...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR KYZ094>097.
WINTER STORM WARNING UNTIL NOON EST TODAY FOR KYZ089>093.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
KYZ098-099.
IN...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR INZ050-058-
059.
WINTER STORM WARNING UNTIL NOON EST TODAY FOR INZ066-073>075-
080.
&&
$$
SYNOPSIS...
NEAR TERM...FRANKS
SHORT TERM...
LONG TERM...HICKMAN
AVIATION...JDR
CLIMATE...
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
701 AM EST MON NOV 17 2014
.SYNOPSIS...
A STORM SYSTEM WILL MOVE EAST OF THE REGION TODAY. ARCTIC AIR WILL
FOLLOW IN THE WAKE OF THE STORM...BRINGING VERY COLD CONDITIONS
THROUGH TUESDAY NIGHT. A COLD FRONT WILL PUSH THROUGH THE AREA
WEDNESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
PRECIPITATION CONTINUES ACROSS ALMOST THE ENTIRE FORECAST AREA
EARLY THIS MORNING. CORRELATION COEFFICIENT ON KILN RADAR
INDICATES THAT THE RAIN-SNOW LINE EXTENDS FROM ROBERTSON COUNTY
NORTHEAST TO HOCKING COUNTY. THIS TRANSITION WILL CONTINUE TO
PUSH EAST THROUGH THE MORNING SO THAT ALL AREAS WILL SEE SNOW
BEFORE THE PRECIPITATION COMES TO AN END.
LATEST HRRR AND RAP RUNS SUGGEST THAT THERE MAY BE A TEMPORARY
LULL IN PRECIPITATION OVER THE NEXT FEW HOURS WITH ONE MORE SURGE
AFTER 12Z. THIS LAST ROUND OF PRECIPITATION WILL QUICKLY MOVE OFF
TO THE EAST OF THE AREA BETWEEN 15Z AND 18Z.
WARM GROUND SEEMS TO BE DOING QUITE A JOB IN LIMITING ACCUMULATIONS
THUS FAR. THIS IS EVEN MORE SO ON PAVEMENT. A MAJORITY OF ROAD
TEMPERATURE SENSORS ACROSS THE FORECAST AREA ARE STILL ABOVE
FREEZING BUT ROADS ARE STARTING TO GET COVERED. AND AS SNOW
CONTINUES AND GROUND TEMPERATURES FALL IN TANDEM WITH COLDER AIR
TEMPERATURES FILTERING IN...SLIPPERY CONDITIONS WILL OCCUR ON
AREA ROADS.
BASED ON ACCUMULATIONS SEEN THUS FAR HAVE PULLED BACK SLIGHTLY ON
STORM TOTAL AMOUNTS. WARNING AREA IS MARGINAL AT THIS POINT BUT
WILL KEEP IT GOING FOR NOW WITH ADDITIONAL SNOW COMING. ADVISORY
AREA REMAINS UNCHANGED.
HIGH TEMPERATURES WILL BE REALIZED EARLY THIS MORNING WITH
READINGS FALLING AS ARCTIC AIR SURGES INTO THE REGION. WEST WINDS
WILL BECOME GUSTY AND FLURRIES WILL LIKELY DEVELOP IN THE
AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
ARCTIC AIR WILL CONTINUE TO POUR INTO THE AREA TONIGHT AND
TUESDAY. THIS WILL KEEP GUSTY WINDS GOING. LOW CLOUDS SHOULD
PERSIST. CLOUD COVER SHOULD BE ENOUGH TO KEEP LOWS JUST ABOVE
RECORD BUT RECORD LOW HIGHS ON TUESDAY ARE A NEAR CERTAINTY.
FLURRIES WILL CONTINUE FROM TIME TO TIME.
FLOW WILL TURN AROUND TO THE SOUTH TUESDAY NIGHT AHEAD OF THE NEXT
SYSTEM BUT TEMPERATURES WILL REMAIN VERY COLD. READINGS WILL
REBOUND RELATIVELY SPEAKING ON WEDNESDAY. HOWEVER A COLD FRONT
WILL PUSH TOWARDS THE REGION AND THEN MOVE THROUGH WEDNESDAY
NIGHT. APPEARS THAT SCATTERED SNOW SHOWERS MAY OCCUR WITH THE
BOUNDARY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
FOR THURSDAY THROUGH FRIDAY...MODELS ARE SOMEWHAT DIFFERENT IN
REGARDS TO THE AMOUNT OF RESURGING ARCTIC AIR THAT WILL BLEED BACK
INTO OUR AREA IN ASSOCIATION WITH SFC HIGH PRESSURE. IT SHOULD BE
DRY...BUT TEMPERATURES WILL STILL BE WELL BELOW NORMAL.
MODELS KEEP ADVERTISING A PATTERN SHIFT FOR THE UPCOMING WEEKEND AS
THE LONGWAVE PATTERN WILL PUSH ARCTIC AIR BACK NORTH INTO CANADA
WHILE A SERIES OF WEATHER SYSTEMS MOVING INTO THE REGION WILL BE OF
A PACIFIC ORIGIN. THERE ARE SOME TIMING ISSUES BUT IT APPEARS THAT
RETURN FLOW/WAA PATTERN ALONG WITH A WEATHER SYSTEM WILL BRING AN
INCREASING THREAT FOR SHOWERS SATURDAY NIGHT INTO SUNDAY.
TEMPERATURES BY SUNDAY ARE FORECAST TO APPROACH NORMAL HIGHS IN THE
MID 40S TO AROUND 50 DEGREES.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
HEAVIEST BURST OF SNOW PULLING THROUGH MOST TAF LOCATIONS AT THIS
TIME WITH IFR CIGS AND VSBYS TO CONTINUE THROUGH 14-15Z. SLOW
IMPROVEMENT THROUGH THE DAY OF VSBYS WITH VFR EXPECTED ONCE MAIN
BAND OF SNOW PULLS OUT...THOUGH LOW MVFR CIGS TO REMAIN THROUGH
MUCH OF THE DAY. FLURRIES AND SPOTTY SNOW SHOWERS THIS AFTERNOON
WILL BRING A CHANCE FOR MVFR VSBYS THROUGH 00Z...THEN VFR CIGS
AFTER ABOUT 05Z.
OUTLOOK...SNOW SQUALLS ON TUESDAY COULD YIELD MVFR/IFR CONDITIONS
AT TIMES.
&&
.CLIMATE...
RECORD LOWS FOR TUESDAY MORNING NOVEMBER 18
CVG...12 DEGREES...1880
CMH...10 DEGREES...1880
DAY...13 DEGREES...1959
RECORD LOW MAX TEMPERATURES ON NOVEMBER 18
CVG...26 DEGREES...1951
CMH...26 DEGREES...1903
DAY...27 DEGREES...1951 AND 1903
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR OHZ026-034-
035-042>045-051>054-060>062.
WINTER STORM WARNING UNTIL NOON EST TODAY FOR OHZ063-064-
070>072-077>080.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
OHZ046-055-056-065-073-074-081-082.
KY...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR KYZ094>097.
WINTER STORM WARNING UNTIL NOON EST TODAY FOR KYZ089>093.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
KYZ098-099.
IN...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR INZ050-058-
059.
WINTER STORM WARNING UNTIL NOON EST TODAY FOR INZ066-073>075-
080.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...HICKMAN
AVIATION...JDR
CLIMATE...
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
528 AM EST MON NOV 17 2014
.SYNOPSIS...
A STORM SYSTEM WILL MOVE EAST OF THE REGION TODAY. ARCTIC AIR WILL
FOLLOW IN THE WAKE OF THE STORM...BRINGING VERY COLD CONDITIONS
THROUGH TUESDAY NIGHT. A COLD FRONT WILL PUSH THROUGH THE AREA
WEDNESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
PRECIPITATION CONTINUES ACROSS ALMOST THE ENTIRE FORECAST AREA
EARLY THIS MORNING. CORRELATION COEFFICIENT ON KILN RADAR
INDICATES THAT THE RAIN-SNOW LINE EXTENDS FROM ROBERTSON COUNTY
NORTHEAST TO HOCKING COUNTY. THIS TRANSITION WILL CONTINUE TO
PUSH EAST THROUGH THE MORNING SO THAT ALL AREAS WILL SEE SNOW
BEFORE THE PRECIPITATION COMES TO AN END.
LATEST HRRR AND RAP RUNS SUGGEST THAT THERE MAY BE A TEMPORARY
LULL IN PRECIPITATION OVER THE NEXT FEW HOURS WITH ONE MORE SURGE
AFTER 12Z. THIS LAST ROUND OF PRECIPITATION WILL QUICKLY MOVE OFF
TO THE EAST OF THE AREA BETWEEN 15Z AND 18Z.
WARM GROUND SEEMS TO BE DOING QUITE A JOB IN LIMITING ACCUMULATIONS
THUS FAR. THIS IS EVEN MORE SO ON PAVEMENT. A MAJORITY OF ROAD
TEMPERATURE SENSORS ACROSS THE FORECAST AREA ARE STILL ABOVE
FREEZING BUT ROADS ARE STARTING TO GET COVERED. AND AS SNOW
CONTINUES AND GROUND TEMPERATURES FALL IN TANDEM WITH COLDER AIR
TEMPERATURES FILTERING IN...SLIPPERY CONDITIONS WILL OCCUR ON
AREA ROADS.
BASED ON ACCUMULATIONS SEEN THUS FAR HAVE PULLED BACK SLIGHTLY ON
STORM TOTAL AMOUNTS. WARNING AREA IS MARGINAL AT THIS POINT BUT
WILL KEEP IT GOING FOR NOW WITH ADDITIONAL SNOW COMING. ADVISORY
AREA REMAINS UNCHANGED.
HIGH TEMPERATURES WILL BE REALIZED EARLY THIS MORNING WITH
READINGS FALLING AS ARCTIC AIR SURGES INTO THE REGION. WEST WINDS
WILL BECOME GUSTY AND FLURRIES WILL LIKELY DEVELOP IN THE
AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
ARCTIC AIR WILL CONTINUE TO POUR INTO THE AREA TONIGHT AND
TUESDAY. THIS WILL KEEP GUSTY WINDS GOING. LOW CLOUDS SHOULD
PERSIST. CLOUD COVER SHOULD BE ENOUGH TO KEEP LOWS JUST ABOVE
RECORD BUT RECORD LOW HIGHS ON TUESDAY ARE A NEAR CERTAINTY.
FLURRIES WILL CONTINUE FROM TIME TO TIME.
FLOW WILL TURN AROUND TO THE SOUTH TUESDAY NIGHT AHEAD OF THE NEXT
SYSTEM BUT TEMPERATURES WILL REMAIN VERY COLD. READINGS WILL
REBOUND RELATIVELY SPEAKING ON WEDNESDAY. HOWEVER A COLD FRONT
WILL PUSH TOWARDS THE REGION AND THEN MOVE THROUGH WEDNESDAY
NIGHT. APPEARS THAT SCATTERED SNOW SHOWERS MAY OCCUR WITH THE
BOUNDARY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
FOR THURSDAY THROUGH FRIDAY...MODELS ARE SOMEWHAT DIFFERENT IN
REGARDS TO THE AMOUNT OF RESURGING ARCTIC AIR THAT WILL BLEED BACK
INTO OUR AREA IN ASSOCIATION WITH SFC HIGH PRESSURE. IT SHOULD BE
DRY...BUT TEMPERATURES WILL STILL BE WELL BELOW NORMAL.
MODELS KEEP ADVERTISING A PATTERN SHIFT FOR THE UPCOMING WEEKEND AS
THE LONGWAVE PATTERN WILL PUSH ARCTIC AIR BACK NORTH INTO CANADA
WHILE A SERIES OF WEATHER SYSTEMS MOVING INTO THE REGION WILL BE OF
A PACIFIC ORIGIN. THERE ARE SOME TIMING ISSUES BUT IT APPEARS THAT
RETURN FLOW/WAA PATTERN ALONG WITH A WEATHER SYSTEM WILL BRING AN
INCREASING THREAT FOR SHOWERS SATURDAY NIGHT INTO SUNDAY.
TEMPERATURES BY SUNDAY ARE FORECAST TO APPROACH NORMAL HIGHS IN THE
MID 40S TO AROUND 50 DEGREES.
&&
.AVIATION /10Z MONDAY THROUGH FRIDAY/...
PCPN FROM THE APPROACHING WINTER STORM HAS YET TO REALLY AFFECT
THE MAJORITY OF THE TAFS. THE ONE EXCEPTION IS KDAY WHEN THE IFR
SNOW HAS ALREADY STARTED. SRN TAFS HAVE SEEN THEIR CIGS ALREADY
FALL TO IFR WHILE THE CENTRAL OHIO TAFS ARE STILL MVFR.
SNOW SHOULD FILL IN ACROSS SRN INDIANA/NRN KENTUCKY AND LIFT UP
THE I-71 CORRIDOR. WORST CONDITIONS WILL OCCUR BETWEEN 06-12Z. AT
KCMH/KLCK THE PCPN SHOULD STAY RAIN LONGER...PAST 06Z...BEFORE
CHANGING TO SNOW. EXPECT IFR CONDITIONS FOR ALL THE TAFS AFT 06Z.
LATEST RUNS OF THE MODELS ARE A LITTLE SLOWER WITH THE BACK
EDGE...SO HELD ONTO LOWER CIGS AND VSBYS UNTIL 13-15Z. AS THE PCPN
ENDS...WINDS WILL SHIFT TO THE WEST AND INCREASE TO 10-15KT...WITH
GUSTS INTO THE 20S. CAA ALOFT ON THE AFTERNOON MAY LEAD TO SOME
SCATTERED SNOW SHOWERS REDUCING CONDITIONS TO MVFR.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES WITH SCATTERED SNOW
SHOWERS ARE POSSIBLE MONDAY AFTERNOON/EVENING. SNOW SQUALLS AGAIN
ON TUESDAY COULD YIELD MVFR/IFR CONDITIONS AT TIMES.
&&
.CLIMATE...
RECORD LOWS FOR TUESDAY MORNING NOVEMBER 18
CVG...12 DEGREES...1880
CMH...10 DEGREES...1880
DAY...13 DEGREES...1959
RECORD LOW MAX TEMPERATURES ON NOVEMBER 18
CVG...26 DEGREES...1951
CMH...26 DEGREES...1903
DAY...27 DEGREES...1951 AND 1903
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR OHZ026-034-
035-042>045-051>054-060>062.
WINTER STORM WARNING UNTIL NOON EST TODAY FOR OHZ063-064-
070>072-077>080.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
OHZ046-055-056-065-073-074-081-082.
KY...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR KYZ094>097.
WINTER STORM WARNING UNTIL NOON EST TODAY FOR KYZ089>093.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
KYZ098-099.
IN...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR INZ050-058-
059.
WINTER STORM WARNING UNTIL NOON EST TODAY FOR INZ066-073>075-
080.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...HICKMAN
AVIATION...JDR
CLIMATE...
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
714 AM CST MON NOV 17 2014
.DISCUSSION...
WIND WEATHER ADVISORIES HAVE BEEN CANCELLED AS PRECIPITATION HAS
MOVED EAST.
&&
PREV DISCUSSION... /ISSUED 441 AM CST MON NOV 17 2014/
CURRENTLY...BANDS OF LIGHT SNOW ARE MOVING ACROSS THE NORTHERN
HALF OF THE MIDSOUTH. SOME SLEET HAS BEEN MIXED IN AROUND THE
MEMPHIS AREA. DECIDED TO GO AHEAD AND EXPAND THE ADVISORY TO
INCLUDE MOST OF THE I-40 CORRIDOR SINCE BRIDGES AND OVERPASSES
COULD BECOME SLICK AHEAD OF THE MONDAY MORNING COMMUTE AS TEMPS
FALL BELOW FREEZING. LATEST HRRR PULLS THESE BANDS NE AND OUT OF
THE AREA BY 7 OR 8 AM. MEANWHILE RAIN HAS CLEARED OUT OF NORTH
MISSISSIPPI.
TODAY...PRECIP WILL QUICKLY EXIT THIS MORNING AND SOME TEMPORARY
CLEARING WILL OCCUR. MEANWHILE MUCH COLDER AIR WILL FILTER IN ON
BRISK NW WINDS. EXPECT COLD AIR STRATOCU TO DEVELOP AND MOVE INTO
THE AREA FROM THE NORTH AS 850 MB TEMPS DROP TO -14C AS FAR SOUTH
AS THE I-40 CORRIDOR THIS AFTERNOON. THE NAM 925 MB RH FIELDS
DEPICT THIS WELL. SOME FLURRIES ARE ALSO POSSIBLE ACROSS THE
NORTH HALF THIS AFTERNOON. TEMPS WILL BE VERY COLD WITH HIGHS
AROUND 30 NEAR THE KY/MO BORDERS TO AROUND 40 SOUTH.
TONIGHT THROUGH TUESDAY NIGHT...ARCTIC HIGH PRESSURE SETTLES OVER
THE REGION. VERY COLD TONIGHT WITH TEMPS DROPPING WELL INTO THE
TEENS. WOULD GO COLDER THAN GUIDANCE EXCEPT THERE IS SOME
GRADIENT LEFT ACROSS THE AREA WHICH WILL KEEP WINDS UP A BIT. THIS
OF COURSE WILL CAUSE WIND CHILLS TO DROPS INTO THE SINGLE DIGITS
ACROSS THE NORTH HALF BY TUESDAY MORNING. TUESDAY WILL BE VERY
COLD WITH UPPER 20S NEAR PARIS TO MID 30S SOUTH. THIS IS PUSHING
35 DEGREES BELOW NORMAL. TEMPS WILL FALL QUICKLY INTO THE 20S
TUESDAY EVENING AND THEN LEVEL OFF AS SOUTH WINDS DEVELOP AHEAD OF
AN APPROACHING SURFACE TROF.
WEDNESDAY AND WEDNESDAY NIGHT...SURFACE TROF MOVES THROUGH WITH
WARMER SW WINDS ACROSS THE AREA AND TEMPS SHOULD CLIMB INTO THE
UPPER 40S AND LOWER 50S...WHICH THOUGH PLEASANT SOUNDING IS STILL
10 DEGREES BELOW NORMAL. WEAK HIGH PRESSURE PREVAILS WEDNESDAY
NIGHT WITH WITH LOWS IN THE 20S AND 30S.
THURSDAY THROUGH THE WEEKEND...00Z MEDIUM RANGE MODELS ARE IN
MUCH BETTER AGREEMENT TODAY. A MAJOR PATTERN SHIFT WILL OCCUR AS
THE COLD UPPER TROF PUSHES EAST AND THE UPPER FLOW BECOME ZONAL BY
THE END OF THE WEEK. AN OVERRUNNING PATTERN SETS UP AS A
DISTURBANCE MOVES THROUGH IN THE ZONAL FLOW ALOFT. AS A RESULT
EXPECT RAIN CHANCES THURSDAY NIGHT AND FRIDAY. BY SATURDAY A
BROAD UPPER RIDGE WILL BUILD OVER THE AREA AS A POTENT MID LEVEL
TROF PUSHES OUT OF THE SW U.S. INTO TEXAS. AS A RESULT EXPECT
WARMER AIR TO START MOVING NORTH INTO THE MIDSOUTH WITH HIGHS IN
THE 50S AND 60S. BY SAT NIGHT AND SUNDAY THE UPPER TROF WILL PUSH
THROUGH WITH SHOWERS AND THUNDERSTORMS LIKELY.
SJM
&&
.AVIATION...
12Z TAFS
BRIEF VFR WEATHER NOW SHIFTING INTO MEM AND JBR...AND WILL FOLLOW
SUITE THIS MORNING AT MKL AND TUP. FOR THIS AFTERNOON EXPECTING A
MVFR DECK TO REFORM...WITH LIGHT SNOW FLURRIES ALSO REDVELOPING.
SECOND CLEARING OF SKY COVER WILL ARRIVE TONIGHT. NORTHWEST TO
NORTH WINDS AT 12-14KTS WITH FREQUENT GUSTS OF 18-20 KTS. WINDS
WILL DIMINISH FOR THE LATTER HALF OF THE CYCLE.
JAB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
521 AM CST MON NOV 17 2014
.DISCUSSION...
UPDATED FOR 12Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 441 AM CST MON NOV 17 2014/
DISCUSSION...
CURRENTLY...BANDS OF LIGHT SNOW ARE MOVING ACROSS THE NORTHERN
HALF OF THE MIDSOUTH. SOME SLEET HAS BEEN MIXED IN AROUND THE
MEMPHIS AREA. DECIDED TO GO AHEAD AND EXPAND THE ADVISORY TO
INCLUDE MOST OF THE I-40 CORRIDOR SINCE BRIDGES AND OVERPASSES
COULD BECOME SLICK AHEAD OF THE MONDAY MORNING COMMUTE AS TEMPS
FALL BELOW FREEZING. LATEST HRRR PULLS THESE BANDS NE AND OUT OF
THE AREA BY 7 OR 8 AM. MEANWHILE RAIN HAS CLEARED OUT OF NORTH
MISSISSIPPI.
TODAY...PRECIP WILL QUICKLY EXIT THIS MORNING AND SOME TEMPORARY
CLEARING WILL OCCUR. MEANWHILE MUCH COLDER AIR WILL FILTER IN ON
BRISK NW WINDS. EXPECT COLD AIR STRATOCU TO DEVELOP AND MOVE INTO
THE AREA FROM THE NORTH AS 850 MB TEMPS DROP TO -14C AS FAR SOUTH
AS THE I-40 CORRIDOR THIS AFTERNOON. THE NAM 925 MB RH FIELDS
DEPICT THIS WELL. SOME FLURRIES ARE ALSO POSSIBLE ACROSS THE
NORTH HALF THIS AFTERNOON. TEMPS WILL BE VERY COLD WITH HIGHS
AROUND 30 NEAR THE KY/MO BORDERS TO AROUND 40 SOUTH.
TONIGHT THROUGH TUESDAY NIGHT...ARCTIC HIGH PRESSURE SETTLES OVER
THE REGION. VERY COLD TONIGHT WITH TEMPS DROPPING WELL INTO THE
TEENS. WOULD GO COLDER THAN GUIDANCE EXCEPT THERE IS SOME
GRADIENT LEFT ACROSS THE AREA WHICH WILL KEEP WINDS UP A BIT. THIS
OF COURSE WILL CAUSE WIND CHILLS TO DROPS INTO THE SINGLE DIGITS
ACROSS THE NORTH HALF BY TUESDAY MORNING. TUESDAY WILL BE VERY
COLD WITH UPPER 20S NEAR PARIS TO MID 30S SOUTH. THIS IS PUSHING
35 DEGREES BELOW NORMAL. TEMPS WILL FALL QUICKLY INTO THE 20S
TUESDAY EVENING AND THEN LEVEL OFF AS SOUTH WINDS DEVELOP AHEAD OF
AN APPROACHING SURFACE TROF.
WEDNESDAY AND WEDNESDAY NIGHT...SURFACE TROF MOVES THROUGH WITH
WARMER SW WINDS ACROSS THE AREA AND TEMPS SHOULD CLIMB INTO THE
UPPER 40S AND LOWER 50S...WHICH THOUGH PLEASANT SOUNDING IS STILL
10 DEGREES BELOW NORMAL. WEAK HIGH PRESSURE PREVAILS WEDNESDAY
NIGHT WITH WITH LOWS IN THE 20S AND 30S.
THURSDAY THROUGH THE WEEKEND...00Z MEDIUM RANGE MODELS ARE IN
MUCH BETTER AGREEMENT TODAY. A MAJOR PATTERN SHIFT WILL OCCUR AS
THE COLD UPPER TROF PUSHES EAST AND THE UPPER FLOW BECOME ZONAL BY
THE END OF THE WEEK. AN OVERRUNNING PATTERN SETS UP AS A
DISTURBANCE MOVES THROUGH IN THE ZONAL FLOW ALOFT. AS A RESULT
EXPECT RAIN CHANCES THURSDAY NIGHT AND FRIDAY. BY SATURDAY A
BROAD UPPER RIDGE WILL BUILD OVER THE AREA AS A POTENT MID LEVEL
TROF PUSHES OUT OF THE SW U.S. INTO TEXAS. AS A RESULT EXPECT
WARMER AIR TO START MOVING NORTH INTO THE MIDSOUTH WITH HIGHS IN
THE 50S AND 60S. BY SAT NIGHT AND SUNDAY THE UPPER TROF WILL PUSH
THROUGH WITH SHOWERS AND THUNDERSTORMS LIKELY.
SJM
&&
.AVIATION...
12Z TAFS
BRIEF VFR WEATHER NOW SHIFTING INTO MEM AND JBR...AND WILL FOLLOW
SUITE THIS MORNING AT MKL AND TUP. FOR THIS AFTERNOON EXPECTING A
MVFR DECK TO REFORM...WITH LIGHT SNOW FLURRIES ALSO REDVELOPING.
SECOND CLEARING OF SKY COVER WILL ARRIVE TONIGHT. NORTHWEST TO
NORTH WINDS AT 12-14KTS WITH FREQUENT GUSTS OF 18-20 KTS. WINDS
WILL DIMINISH FOR THE LATTER HALF OF THE CYCLE.
JAB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
CLAY-CRAIGHEAD-GREENE-LAWRENCE-MISSISSIPPI-POINSETT-
RANDOLPH.
WINTER WEATHER ADVISORY UNTIL 8 AM CST THIS MORNING FOR
CRITTENDEN.
MO...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
DUNKLIN-PEMISCOT.
MS...WINTER WEATHER ADVISORY UNTIL 8 AM CST THIS MORNING FOR DESOTO.
TN...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
LAKE-OBION.
WINTER WEATHER ADVISORY UNTIL 8 AM CST THIS MORNING FOR BENTON
TN-CARROLL-CHESTER-CROCKETT-DECATUR-DYER-FAYETTE-GIBSON-
HARDEMAN-HAYWOOD-HENDERSON-HENRY-LAUDERDALE-MADISON-SHELBY-
TIPTON-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
441 AM CST MON NOV 17 2014
.DISCUSSION...
CURRENTLY...BANDS OF LIGHT SNOW ARE MOVING ACROSS THE NORTHERN
HALF OF THE MIDSOUTH. SOME SLEET HAS BEEN MIXED IN AROUND THE
MEMPHIS AREA. DECIDED TO GO AHEAD AND EXPAND THE ADVISORY TO
INCLUDE MOST OF THE I-40 CORRIDOR SINCE BRIDGES AND OVERPASSES
COULD BECOME SLICK AHEAD OF THE MONDAY MORNING COMMUTE AS TEMPS
FALL BELOW FREEZING. LATEST HRRR PULLS THESE BANDS NE AND OUT OF
THE AREA BY 7 OR 8 AM. MEANWHILE RAIN HAS CLEARED OUT OF NORTH
MISSISSIPPI.
TODAY...PRECIP WILL QUICKLY EXIT THIS MORNING AND SOME TEMPORARY
CLEARING WILL OCCUR. MEANWHILE MUCH COLDER AIR WILL FILTER IN ON
BRISK NW WINDS. EXPECT COLD AIR STRATOCU TO DEVELOP AND MOVE INTO
THE AREA FROM THE NORTH AS 850 MB TEMPS DROP TO -14C AS FAR SOUTH
AS THE I-40 CORRIDOR THIS AFTERNOON. THE NAM 925 MB RH FIELDS
DEPICT THIS WELL. SOME FLURRIES ARE ALSO POSSIBLE ACROSS THE
NORTH HALF THIS AFTERNOON. TEMPS WILL BE VERY COLD WITH HIGHS
AROUND 30 NEAR THE KY/MO BORDERS TO AROUND 40 SOUTH.
TONIGHT THROUGH TUESDAY NIGHT...ARCTIC HIGH PRESSURE SETTLES OVER
THE REGION. VERY COLD TONIGHT WITH TEMPS DROPPING WELL INTO THE
TEENS. WOULD GO COLDER THAN GUIDANCE EXCEPT THERE IS SOME
GRADIENT LEFT ACROSS THE AREA WHICH WILL KEEP WINDS UP A BIT. THIS
OF COURSE WILL CAUSE WIND CHILLS TO DROPS INTO THE SINGLE DIGITS
ACROSS THE NORTH HALF BY TUESDAY MORNING. TUESDAY WILL BE VERY
COLD WITH UPPER 20S NEAR PARIS TO MID 30S SOUTH. THIS IS PUSHING
35 DEGREES BELOW NORMAL. TEMPS WILL FALL QUICKLY INTO THE 20S
TUESDAY EVENING AND THEN LEVEL OFF AS SOUTH WINDS DEVELOP AHEAD OF
AN APPROACHING SURFACE TROF.
WEDNESDAY AND WEDNESDAY NIGHT...SURFACE TROF MOVES THROUGH WITH
WARMER SW WINDS ACROSS THE AREA AND TEMPS SHOULD CLIMB INTO THE
UPPER 40S AND LOWER 50S...WHICH THOUGH PLEASANT SOUNDING IS STILL
10 DEGREES BELOW NORMAL. WEAK HIGH PRESSURE PREVAILS WEDNESDAY
NIGHT WITH WITH LOWS IN THE 20S AND 30S.
THURSDAY THROUGH THE WEEKEND...00Z MEDIUM RANGE MODELS ARE IN
MUCH BETTER AGREEMENT TODAY. A MAJOR PATTERN SHIFT WILL OCCUR AS
THE COLD UPPER TROF PUSHES EAST AND THE UPPER FLOW BECOME ZONAL BY
THE END OF THE WEEK. AN OVERRUNNING PATTERN SETS UP AS A
DISTURBANCE MOVES THROUGH IN THE ZONAL FLOW ALOFT. AS A RESULT
EXPECT RAIN CHANCES THURSDAY NIGHT AND FRIDAY. BY SATURDAY A
BROAD UPPER RIDGE WILL BUILD OVER THE AREA AS A POTENT MID LEVEL
TROF PUSHES OUT OF THE SW U.S. INTO TEXAS. AS A RESULT EXPECT
WARMER AIR TO START MOVING NORTH INTO THE MIDSOUTH WITH HIGHS IN
THE 50S AND 60S. BY SAT NIGHT AND SUNDAY THE UPPER TROF WILL PUSH
THROUGH WITH SHOWERS AND THUNDERSTORMS LIKELY.
SJM
&&
.AVIATION...
06Z TAFS
LIGHT WINTRY PRECIP EVENT UNDERWAY AT LATE EVENING FOR JBR AND
FOR A FEW HOURS DURING THE OVERNIGHT...MEM AND MKL. PL POTENTIAL
APPEARS A BIT LESS AT MEM WITH RADAR RETURNS MORE INDICATIVE OF
SNOW ALOFT. NONETHELESS...CAN/T RULE OUT A VERY BRIEF PL EPISODE
AT MEM THROUGH 08Z. SN ACCUMULATION AT MEM SHOULD BE 1/2 INCH OR
LESS ON ELEVATED SURFACES.
VFR WILL PREVAIL AREAWIDE ON MONDAY...WITH VERY DRY REINFORCING
ARCTIC AIR FLOWING INTO THE MIDSOUTH.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
CLAY-CRAIGHEAD-GREENE-LAWRENCE-MISSISSIPPI-POINSETT-
RANDOLPH.
WINTER WEATHER ADVISORY UNTIL 8 AM CST THIS MORNING FOR
CRITTENDEN.
MO...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
DUNKLIN-PEMISCOT.
MS...WINTER WEATHER ADVISORY UNTIL 8 AM CST THIS MORNING FOR DESOTO.
TN...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
LAKE-OBION.
WINTER WEATHER ADVISORY UNTIL 8 AM CST THIS MORNING FOR BENTON
TN-CARROLL-CHESTER-CROCKETT-DECATUR-DYER-FAYETTE-GIBSON-
HARDEMAN-HAYWOOD-HENDERSON-HENRY-LAUDERDALE-MADISON-SHELBY-
TIPTON-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
943 AM CST MON NOV 17 2014
.UPDATE...
TO REMOVE FREEZE WARNING.
&&
.DISCUSSION...
TEMPERATURES HAVE WARMED BACK ABOVE FREEZING AND THE FREEZE
WARNING HAS EXPIRED. SENDING NEW ZONES TO REMOVE THE FREEZE
WARNING HEADLINE.
&&
.PREV DISCUSSION... /ISSUED 534 AM CST MON NOV 17 2014/
AVIATION... /12Z TAF UPDATE/
MVFR CIGS CLEARED RAPIDLY OVER THE PAST SEVERAL HOURS...AND VFR
SKIES ARE FORECAST FOR THE REST OF THE TAF PERIODS. SOME STRONG
LOW LEVEL NORTHERLIES WILL ADD SOME GUST POTENTIAL FOR DRT THROUGH
16Z AND FOR THE I-35 TERMINAL SITES THROUGH 20Z. THE HIGHER GUSTS
SHOULD BE GENERALLY AROUND 25 KNOTS. LIGHT WINDS ARE FORECAST BY
THIS EVENING.
PREV DISCUSSION... /ISSUED 422 AM CST MON NOV 17 2014/
SHORT TERM (TODAY THROUGH TUESDAY)...
EARLY MORNING OBSERVATIONS REVEAL A STEADY FALL IN TEMPERATURES AS
COLD AIR POURS INTO THE REGION AND LOW CLOUDS DECREASE. BASED ON
THE LATEST OBSERVATIONS AND THE HRRR GUIDANCE...WE HAVE OPTED FOR
A FREEZE WARNING FOR COUNTIES ALONG AND NEAR THE U.S. HIGHWAY 90
CORRIDOR. WELL BELOW NORMAL HIGH TEMPERATURES ARE EXPECTED ACROSS
ALL OF SOUTH CENTRAL TEXAS TODAY AS SURFACE HIGH PRESSURE BUILDS.
HIGHS WILL RANGE FROM THE UPPER 40S IN THE HILL COUNTRY TO THE
LOWER 50S ALONG THE RIO GRANDE. WE EXPECT GUSTY NORTH WINDS TO
CONTINUE THROUGH MID-AFTERNOON. WINDS WILL THEN DECREASE QUICKLY
BY SUNSET AS THE PRESSURE GRADIENT RELAXES. TEMPERATURES WILL FALL
BELOW FREEZING ACROSS THE VAST MAJORITY OF SOUTH CENTRAL TEXAS
TONIGHT. LOWS IN THE 20S ARE EXPECTED FOR MOST AREAS TONIGHT. THE
EXCEPTION WILL BE ALONG THE SOUTHERN RIO GRANDE PLAINS...WHERE
LOWS MAY REMAIN CLOSER TO FREEZING. BELOW NORMAL HIGH TEMPERATURES
ARE EXPECTED AGAIN ON TUESDAY WITH HIGHS IN THE 50S.
LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...
A WARMING TREND IS EXPECTED THROUGH THE REMAINDER OF THE WORK WEEK
AND UPCOMING WEEKEND AS SOUTHERLY FLOW IN THE LOW-LEVELS REMAINS
INTACT. THERE IS SOME INDICATION IN THE MODELS WE COULD SEE A WEAK
COLD FRONT MOVE INTO THE HILL COUNTRY ON FRIDAY. THIS FEATURE IS
RATHER WEAK AND WOULD LIKELY NOT HAVE A SIGNIFICANT IMPACT ON
TEMPERATURES. DRY WEATHER IS EXPECTED ON WEDNESDAY...WITH RAIN
CHANCES RETURNING TO THE FORECAST ON THURSDAY FOR AREAS EAST OF
I-35. RAIN CHANCES EXPAND WESTWARD FRIDAY AND SATURDAY AS AN UPPER
LEVEL TROUGH APPROACHES FROM THE WEST. THIS UPPER LEVEL TROUGH
WILL AID IN SENDING A PACIFIC COLD FRONT INTO THE REGION LATE
SATURDAY INTO SUNDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 50 27 53 36 61 / 0 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 51 23 53 32 60 / 0 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 53 27 54 35 61 / 0 0 0 0 0
BURNET MUNI AIRPORT 48 25 52 32 61 / 0 0 0 0 0
DEL RIO INTL AIRPORT 53 30 53 35 59 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 49 22 52 33 60 / 0 0 0 0 0
HONDO MUNI AIRPORT 52 24 52 34 55 / 0 0 0 0 0
SAN MARCOS MUNI AIRPORT 52 26 53 33 59 / 0 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 50 27 52 34 60 / 0 0 - 0 10
SAN ANTONIO INTL AIRPORT 53 27 53 38 60 / 0 0 0 0 0
STINSON MUNI AIRPORT 53 30 54 37 59 / 0 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...76
SYNOPTIC/GRIDS...05
PUBLIC SERVICE/DATA COLLECTION...12
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
534 AM CST MON NOV 17 2014
.AVIATION... /12Z TAF UPDATE/
MVFR CIGS CLEARED RAPIDLY OVER THE PAST SEVERAL HOURS...AND VFR
SKIES ARE FORECAST FOR THE REST OF THE TAF PERIODS. SOME STRONG
LOW LEVEL NORTHERLIES WILL ADD SOME GUST POTENTIAL FOR DRT THROUGH
16Z AND FOR THE I-35 TERMINAL SITES THROUGH 20Z. THE HIGHER GUSTS
SHOULD BE GENERALLY AROUND 25 KNOTS. LIGHT WINDS ARE FORECAST BY
THIS EVENING.
&&
.PREV DISCUSSION... /ISSUED 422 AM CST MON NOV 17 2014/
SHORT TERM (TODAY THROUGH TUESDAY)...
EARLY MORNING OBSERVATIONS REVEAL A STEADY FALL IN TEMPERATURES AS
COLD AIR POURS INTO THE REGION AND LOW CLOUDS DECREASE. BASED ON
THE LATEST OBSERVATIONS AND THE HRRR GUIDANCE...WE HAVE OPTED FOR
A FREEZE WARNING FOR COUNTIES ALONG AND NEAR THE U.S. HIGHWAY 90
CORRIDOR. WELL BELOW NORMAL HIGH TEMPERATURES ARE EXPECTED ACROSS
ALL OF SOUTH CENTRAL TEXAS TODAY AS SURFACE HIGH PRESSURE BUILDS.
HIGHS WILL RANGE FROM THE UPPER 40S IN THE HILL COUNTRY TO THE
LOWER 50S ALONG THE RIO GRANDE. WE EXPECT GUSTY NORTH WINDS TO
CONTINUE THROUGH MID-AFTERNOON. WINDS WILL THEN DECREASE QUICKLY
BY SUNSET AS THE PRESSURE GRADIENT RELAXES. TEMPERATURES WILL FALL
BELOW FREEZING ACROSS THE VAST MAJORITY OF SOUTH CENTRAL TEXAS
TONIGHT. LOWS IN THE 20S ARE EXPECTED FOR MOST AREAS TONIGHT. THE
EXCEPTION WILL BE ALONG THE SOUTHERN RIO GRANDE PLAINS...WHERE
LOWS MAY REMAIN CLOSER TO FREEZING. BELOW NORMAL HIGH TEMPERATURES
ARE EXPECTED AGAIN ON TUESDAY WITH HIGHS IN THE 50S.
LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...
A WARMING TREND IS EXPECTED THROUGH THE REMAINDER OF THE WORK WEEK
AND UPCOMING WEEKEND AS SOUTHERLY FLOW IN THE LOW-LEVELS REMAINS
INTACT. THERE IS SOME INDICATION IN THE MODELS WE COULD SEE A WEAK
COLD FRONT MOVE INTO THE HILL COUNTRY ON FRIDAY. THIS FEATURE IS
RATHER WEAK AND WOULD LIKELY NOT HAVE A SIGNIFICANT IMPACT ON
TEMPERATURES. DRY WEATHER IS EXPECTED ON WEDNESDAY...WITH RAIN
CHANCES RETURNING TO THE FORECAST ON THURSDAY FOR AREAS EAST OF
I-35. RAIN CHANCES EXPAND WESTWARD FRIDAY AND SATURDAY AS AN UPPER
LEVEL TROUGH APPROACHES FROM THE WEST. THIS UPPER LEVEL TROUGH
WILL AID IN SENDING A PACIFIC COLD FRONT INTO THE REGION LATE
SATURDAY INTO SUNDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 50 27 53 36 61 / 0 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 51 23 53 32 60 / 0 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 53 27 54 35 61 / 0 0 0 0 0
BURNET MUNI AIRPORT 48 25 52 32 61 / 0 0 0 0 0
DEL RIO INTL AIRPORT 53 30 53 35 59 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 49 22 52 33 60 / 0 0 0 0 0
HONDO MUNI AIRPORT 52 24 52 34 55 / 0 0 0 0 0
SAN MARCOS MUNI AIRPORT 52 26 53 33 59 / 0 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 50 27 52 34 60 / 0 0 - 0 10
SAN ANTONIO INTL AIRPORT 53 27 53 38 60 / 0 0 0 0 0
STINSON MUNI AIRPORT 53 30 54 37 59 / 0 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING
COUNTIES: BEXAR...CALDWELL...COMAL...FAYETTE...GONZALES...
GUADALUPE...KINNEY...MEDINA...UVALDE...VAL VERDE...WILSON.
&&
$$
MESOSCALE/AVIATION...18
SYNOPTIC/GRIDS...24
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
527 AM CST MON NOV 17 2014
.AVIATION...
VFR AND SKC WITH LIGHT WINDS THRU 18/12Z.
&&
.PREV DISCUSSION... /ISSUED 412 AM CST MON NOV 17 2014/
SHORT TERM...
DEEP AND DRY NORTHERLY FLOW OCCUPIED THE ENTIRE EXTENT OF THE
GREAT PLAINS THIS MORNING AND THIS THEME WILL REMAIN INTACT
THROUGH TONIGHT. A BROAD MERIDIONAL SURFACE RIDGE ANCHORED IN THE
LEE OF THE ROCKIES WILL SHIFT SLOWLY EAST TODAY AND BE LOCATED OFF
THE CAPROCK BY THE AFTERNOON AHEAD OF MILDER SW BREEZES. SNOWPACK
COLOR CURVE ON IR IMAGERY SHOWS THAT THE NAM AND RUC INITIALIZED
THE SNOW COVER RATHER WELL ACROSS OUR NORTHERN TWO ROWS OF
COUNTIES...SO WITH THIS IN MIND WE HAVE SCALED BACK MAX TEMPS IN
THESE AREAS AS 1 TO 3 INCHES OF SNOW WILL CERTAINLY STUNT
RADIATIONAL WARMING...ESPECIALLY AFTER SOME BITTER LOWS TO START
THE DAY. AWAY FROM THE SNOW COVER... WENT WITH THE MILD MET
NUMBERS AS THESE DRY AIRMASSES OFTEN WARM SURPRISINGLY FAST UNDER
FULL SUN WITH DOWNSLOPING WINDS. STEADY SW WINDS AREA WIDE TONIGHT
WILL MAKE FOR MILDER LOWS...HOWEVER EVEN THESE ARE STILL 10 TO 20
DEGREES BELOW CLIMO.
LONG TERM...
PROGRESSIVE PATTERN WILL DEVELOP THIS WEEK WITH A WEAK SHORTWAVE
MOVING OVER THE REGION TOMORROW. THIS WAVE WILL BRING LITTLE IN
THE WAY OF SENSIBLE WEATHER CHANGES. A BIT STRONGER SHORTWAVE WILL
MOVE OVER THE AREA DURING THE DAY THURSDAY WHICH THE MODELS HAVE
SLIGHT TIMING AND STRENGTH DIFFERENCES. AHEAD OF THIS SHORTWAVE
TROUGH...LOW LEVEL MOISTURE WILL TRY TO STREAM NORTHWARD AND SOME
BOUNDARY LAYER MOISTURE MAY MANAGE TO MAKE IT INTO THE ROLLING
PLAINS. INCREASED HIGH CLOUDS WITH THIS WAVE ALONG WITH THE
INCREASED MOISTURE MAY LIMIT THE AMOUNT OF WARMING THAT WILL TAKE
PLACE. WITH THE BEST MOISTURE RETURN TAKING PLACE EAST OF THE
FORECAST AREA...RAIN CHANCES LOOK TO STAY TOO FAR TO THE EAST OF
US TO PUT ANY MENTION IN THE FORECAST.
AS THIS WAVE PASSES BY...A WEAK COLD FRONT WILL MOVE ACROSS THE
AREA BUT ONLY DROP TEMPS BY A FEW DEGREES. A MUCH STRONGER WAVE IS
FORECAST TO MOVE OVER THE REGION DURING THE DAY SATURDAY. MODELS
ARE STILL STRUGGLING WITH HOW STRONG THIS WAVE WILL BE.
REGARDLESS...BOUNDARY LAYER MOISTURE CREEPS INTO THE ROLLING
PLAINS AND ONTO THE CAPROCK BY SATURDAY AFTERNOON. IF THE CURRENT
SOLUTIONS HOLD TRUE...WE MAY SEE SOME SHOWER/THUNDERSTORM ACTIVITY
ACROSS THE REGION. DID NOT FEEL CONFIDENT ENOUGH TO GO WITH LOW-
END CHANCE AT THIS TIME BUT DID BRING SLIGHT CHANCE POPS ACROSS
ALL BUT THE NORTHWESTERN SOUTH PLAINS.
JORDAN
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 34 14 46 24 49 / 0 0 0 0 0
TULIA 35 16 47 26 50 / 0 0 0 0 0
PLAINVIEW 37 18 48 26 51 / 0 0 0 0 0
LEVELLAND 39 20 49 27 52 / 0 0 0 0 0
LUBBOCK 40 19 48 28 52 / 0 0 0 0 0
DENVER CITY 39 21 50 27 54 / 0 0 0 0 0
BROWNFIELD 40 21 50 28 53 / 0 0 0 0 0
CHILDRESS 37 20 50 29 54 / 0 0 0 0 0
SPUR 41 22 49 31 54 / 0 0 0 0 0
ASPERMONT 42 22 51 32 57 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
93
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
422 AM CST MON NOV 17 2014
.SHORT TERM (TODAY THROUGH TUESDAY)...
EARLY MORNING OBSERVATIONS REVEAL A STEADY FALL IN TEMPERATURES AS
COLD AIR POURS INTO THE REGION AND LOW CLOUDS DECREASE. BASED ON
THE LATEST OBSERVATIONS AND THE HRRR GUIDANCE...WE HAVE OPTED FOR
A FREEZE WARNING FOR COUNTIES ALONG AND NEAR THE U.S. HIGHWAY 90
CORRIDOR. WELL BELOW NORMAL HIGH TEMPERATURES ARE EXPECTED ACROSS
ALL OF SOUTH CENTRAL TEXAS TODAY AS SURFACE HIGH PRESSURE BUILDS.
HIGHS WILL RANGE FROM THE UPPER 40S IN THE HILL COUNTRY TO THE
LOWER 50S ALONG THE RIO GRANDE. WE EXPECT GUSTY NORTH WINDS TO
CONTINUE THROUGH MID-AFTERNOON. WINDS WILL THEN DECREASE QUICKLY
BY SUNSET AS THE PRESSURE GRADIENT RELAXES. TEMPERATURES WILL FALL
BELOW FREEZING ACROSS THE VAST MAJORITY OF SOUTH CENTRAL TEXAS
TONIGHT. LOWS IN THE 20S ARE EXPECTED FOR MOST AREAS TONIGHT. THE
EXCEPTION WILL BE ALONG THE SOUTHERN RIO GRANDE PLAINS...WHERE
LOWS MAY REMAIN CLOSER TO FREEZING. BELOW NORMAL HIGH TEMPERATURES
ARE EXPECTED AGAIN ON TUESDAY WITH HIGHS IN THE 50S.
&&
.LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...
A WARMING TREND IS EXPECTED THROUGH THE REMAINDER OF THE WORK WEEK
AND UPCOMING WEEKEND AS SOUTHERLY FLOW IN THE LOW-LEVELS REMAINS
INTACT. THERE IS SOME INDICATION IN THE MODELS WE COULD SEE A WEAK
COLD FRONT MOVE INTO THE HILL COUNTRY ON FRIDAY. THIS FEATURE IS
RATHER WEAK AND WOULD LIKELY NOT HAVE A SIGNIFICANT IMPACT ON
TEMPERATURES. DRY WEATHER IS EXPECTED ON WEDNESDAY...WITH RAIN
CHANCES RETURNING TO THE FORECAST ON THURSDAY FOR AREAS EAST OF
I-35. RAIN CHANCES EXPAND WESTWARD FRIDAY AND SATURDAY AS AN UPPER
LEVEL TROUGH APPROACHES FROM THE WEST. THIS UPPER LEVEL TROUGH
WILL AID IN SENDING A PACIFIC COLD FRONT INTO THE REGION LATE
SATURDAY INTO SUNDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 50 27 53 36 61 / 0 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 51 23 53 32 60 / 0 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 53 27 54 35 61 / 0 0 0 0 0
BURNET MUNI AIRPORT 48 25 52 32 61 / 0 0 0 0 0
DEL RIO INTL AIRPORT 53 30 53 35 59 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 49 22 52 33 60 / 0 0 0 0 0
HONDO MUNI AIRPORT 52 24 52 34 55 / 0 0 0 0 0
SAN MARCOS MUNI AIRPORT 52 26 53 33 59 / 0 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 50 27 52 34 60 / 0 0 - 0 10
SAN ANTONIO INTL AIRPORT 53 27 53 38 60 / 0 0 0 0 0
STINSON MUNI AIRPORT 53 30 54 37 59 / 0 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING
COUNTIES: BEXAR...CALDWELL...COMAL...FAYETTE...GONZALES...
GUADALUPE...KINNEY...MEDINA...UVALDE...VAL VERDE...WILSON.
&&
$$
MESOSCALE/AVIATION...18
SYNOPTIC/GRIDS...24
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
412 AM CST MON NOV 17 2014
.SHORT TERM...
DEEP AND DRY NORTHERLY FLOW OCCUPIED THE ENTIRE EXTENT OF THE
GREAT PLAINS THIS MORNING AND THIS THEME WILL REMAIN INTACT
THROUGH TONIGHT. A BROAD MERIDIONAL SURFACE RIDGE ANCHORED IN THE
LEE OF THE ROCKIES WILL SHIFT SLOWLY EAST TODAY AND BE LOCATED OFF
THE CAPROCK BY THE AFTERNOON AHEAD OF MILDER SW BREEZES. SNOWPACK
COLOR CURVE ON IR IMAGERY SHOWS THAT THE NAM AND RUC INITIALIZED
THE SNOW COVER RATHER WELL ACROSS OUR NORTHERN TWO ROWS OF
COUNTIES...SO WITH THIS IN MIND WE HAVE SCALED BACK MAX TEMPS IN
THESE AREAS AS 1 TO 3 INCHES OF SNOW WILL CERTAINLY STUNT
RADIATIONAL WARMING...ESPECIALLY AFTER SOME BITTER LOWS TO START
THE DAY. AWAY FROM THE SNOW COVER... WENT WITH THE MILD MET
NUMBERS AS THESE DRY AIRMASSES OFTEN WARM SURPRISINGLY FAST UNDER
FULL SUN WITH DOWNSLOPING WINDS. STEADY SW WINDS AREA WIDE TONIGHT
WILL MAKE FOR MILDER LOWS...HOWEVER EVEN THESE ARE STILL 10 TO 20
DEGREES BELOW CLIMO.
&&
.LONG TERM...
PROGRESSIVE PATTERN WILL DEVELOP THIS WEEK WITH A WEAK SHORTWAVE
MOVING OVER THE REGION TOMORROW. THIS WAVE WILL BRING LITTLE IN
THE WAY OF SENSIBLE WEATHER CHANGES. A BIT STRONGER SHORTWAVE WILL
MOVE OVER THE AREA DURING THE DAY THURSDAY WHICH THE MODELS HAVE
SLIGHT TIMING AND STRENGTH DIFFERENCES. AHEAD OF THIS SHORTWAVE
TROUGH...LOW LEVEL MOISTURE WILL TRY TO STREAM NORTHWARD AND SOME
BOUNDARY LAYER MOISTURE MAY MANAGE TO MAKE IT INTO THE ROLLING
PLAINS. INCREASED HIGH CLOUDS WITH THIS WAVE ALONG WITH THE
INCREASED MOISTURE MAY LIMIT THE AMOUNT OF WARMING THAT WILL TAKE
PLACE. WITH THE BEST MOISTURE RETURN TAKING PLACE EAST OF THE
FORECAST AREA...RAIN CHANCES LOOK TO STAY TOO FAR TO THE EAST OF
US TO PUT ANY MENTION IN THE FORECAST.
AS THIS WAVE PASSES BY...A WEAK COLD FRONT WILL MOVE ACROSS THE
AREA BUT ONLY DROP TEMPS BY A FEW DEGREES. A MUCH STRONGER WAVE IS
FORECAST TO MOVE OVER THE REGION DURING THE DAY SATURDAY. MODELS
ARE STILL STRUGGLING WITH HOW STRONG THIS WAVE WILL BE.
REGARDLESS...BOUNDARY LAYER MOISTURE CREEPS INTO THE ROLLING
PLAINS AND ONTO THE CAPROCK BY SATURDAY AFTERNOON. IF THE CURRENT
SOLUTIONS HOLD TRUE...WE MAY SEE SOME SHOWER/THUNDERSTORM ACTIVITY
ACROSS THE REGION. DID NOT FEEL CONFIDENT ENOUGH TO GO WITH LOW-
END CHANCE AT THIS TIME BUT DID BRING SLIGHT CHANCE POPS ACROSS
ALL BUT THE NORTHWESTERN SOUTH PLAINS.
JORDAN
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 34 14 46 24 49 / 0 0 0 0 0
TULIA 35 16 47 26 50 / 0 0 0 0 0
PLAINVIEW 37 18 48 26 51 / 0 0 0 0 0
LEVELLAND 39 20 49 27 52 / 0 0 0 0 0
LUBBOCK 40 19 48 28 52 / 0 0 0 0 0
DENVER CITY 39 21 50 27 54 / 0 0 0 0 0
BROWNFIELD 40 21 50 28 53 / 0 0 0 0 0
CHILDRESS 37 20 50 29 54 / 0 0 0 0 0
SPUR 41 22 49 31 54 / 0 0 0 0 0
ASPERMONT 42 22 51 32 57 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
93/14
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1102 AM EST MON NOV 17 2014
.SYNOPSIS...
A STRONG COLD FRONT SWINGS ACROSS THE AREA TODAY. ARCTIC AIR WILL
FOLLOW TONIGHT WITH HIGH PRESSURE MOVING INTO THE MID MISSISSIPPI
VALLEY. EXPECT A PERIOD OF SNOW SHOWERS...WINDS AND COLD WIND
CHILLS LATE TONIGHT INTO TUESDAY MORNING AS A RESULT.
HIGH PRESSURE BUILDS ACROSS THE SOUTHEAST INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1040 AM EST MONDAY...
BASED ON LATEST SURFACE OBSERVATIONS... THE COLD FRONT APPEARS TO
BE MOVING A COUPLE HOURS AHEAD OF THE PREVIOUS FORECAST. THIS IS
REFLECTED IN THE FORECAST WITH REDUCED TEMPERATURES AND EARLIER
ONSET OF SNOW IN THE WESTERN SLOPES. SNOW IS NOW FORECAST TO BEGIN
AROUND 3PM FOR WESTERN GREENBRIER COUNTRY.
PREVIOUS DISCUSSION...
EARLIER RUN OF THE HRRR HAD A GREAT HANDLE ON THE RAIN MOVING IN
FROM THE SOUTHWEST. FOLLOWED ITS SOLUTION THROUGH THE
MORNING...BLENDING IN THE 00Z GFS/NAM. LOOKS LIKE A SLAM DUNK FOR
EVERYONE SEEING RAIN TODAY...THOUGH AMOUNTS MAY BE LESS THAN EARLIER
THOUGHT AS DID NOT SEE AS MUCH FALL SUNDAY.
STILL A GOOD ONE HALF TO THREE QUARTERS OF AN INCH WILL OCCUR TODAY.
THIS FRONT LOCATED ACROSS THE CENTRAL APPALACHIANS SOUTHWEST INTO
ALABAMA WILL SLIDE EAST ACROSS THE AREA TODAY...WITH A COUPLE WAVES
OF LOW PRESSURE ALONG IT. THE MAIN FORECAST ISSUE WILL BE THE COLDER
AIR ARRIVING BEHIND THE FRONT. THE 00Z NAM DEPICTED THE COLDER AIR
BETTER AT 06Z AT 8H THAN THE GFS/ECMWF...SO LEANED TOWARD IT TEMP
FORECAST. SHOULD SEE DEEP MOISTURE EDGE EAST EARLY THIS AFTERNOON IN
THE MTNS WHILE THE COLDER AIR STARTS TURNING RESIDUAL SHOWERS OVER
TO SNOW LATER IN THE AFTERNOON. BY DUSK MOST OF THE EASTERN HALF OF
THE CWA WILL BE DRYING OUT AS WINDS TURN WNW. TEMPS DESPITE THE
RAIN...OR REALLY AS A RESULT OF THE RAIN BRINGING DOWN THE WARMER
TEMPS ALOFT MAY BRING READINGS INTO THE 50S BEFORE THE COLD AIR
ARRIVES IN THE PIEDMONT THIS AFTERNOON. IN THE MTNS HIGHS SHOULD BE
OCCURRING BY MIDDAY THEN DROPPING IN THE LATE AFTERNOON.
FORECAST SOUNDINGS IN THE MTNS SHOW MOISTURE BECOMING SHALLOW
FAST...WITH THE FAVORABLE SNOW GROWTH TEMPS ALOFT NOT BEING REALIZED
UNTIL LATE EVENING...SO COULD BE SOME PATCHY FREEZING DRIZZLE
ISSUES...AND WILL ADVERTISE THIS IN THE MTNS OF THE FAR WEST THIS
EVENING. THIS HERE LIES THE PROBLEM...WHERE IT RAINS...COMBINED WITH
ARCTIC AIR ARRIVING AND SNIZZLE(SNOW AND FREEZING DRIZZLE)
FOLLOWING...ROADS WILL BECOME SLICK IN THE HIGHER ELEVATIONS BY LATE
DUSK. AFTER COLLABORATING WITH NEIGHBORING OFFICES...IT WAS DECIDED
TO GO WITH A WINTER WX ADVISORY FOR THE NC MTNS INTO THE GRAYSON
HIGHLANDS...BUT TO DELAY ANY HEADLINES...IF THEY ARE NEEDED FURTHER
NORTH INTO THE MTN EMPIRE OF SW VA AND SE WV MTNS. STILL THINK THE
TEMPS FALLING FAST LATE TONIGHT MAY REQUIRE AT LEAST A SPECIAL WX
STATEMENT. THE SNOWFALL ACCUMULATION WILL BE LIGHT GIVEN THE LIMITED
MOISTURE BUT 1 TO 3 INCHES IN THE WESTERN SLOPES ARE POSSIBLE INTO
TUESDAY MORNING.
IN ADDITION...THE WINDS WILL BE GUSTING OVER 40 MPH WITH 6 HR
PRESSURE RISES OF 5-7MB EXPECTED BEHIND THE FRONT THIS EVENING INTO
TUESDAY MORNING. THIS WAS ADDED TO THE WINTER WX ADVISORY IN THE NC
MTNS. CLOUDS MAY PREVENT IDEAL MIXING OF THE STRONGER WINDS
ALOFT...BUT WHERE IT THE CLOUD/CLEARING LINE IS ALONG/NEAR THE BLUE
RIDGE...THINK AN OCCASIONAL 50 MPH GUST WILL BE REALIZED. OUTSIDE
THE WINTER WX ADVISORY FOR ELEVATIONS ABOVE 3000 FT...HIGHLIGHT
WEATHER IN THE HAZARDOUS WEATHER OUTLOOK. WILL TAKE A LOOK AT MORE
DATA COMING IN AND FURTHER COORDINATING WITH OTHER WFO OFFICES TO
SEE IF MORE HEADLINES ARE NEEDED.
FOR TONIGHT...TEMPS WILL DROP INTO THE TEENS MOUNTAINS...SOME SINGLE
DIGITS HIGHEST ELEVATIONS...WITH 20S IN THE EAST. WIND CHILLS BY
DAWN TUESDAY WILL RANGE FROM 5 ABOVE TO 5 BELOW IN THE
MOUNTAINS...TO THE TEENS IN THE EAST.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 315 AM EST MONDAY...
COLD FRONT PUSHES OUT INTO THE ATLANTIC OCEAN TUESDAY AS THE 1033
SURFACE HIGH PRESSURE IN TEXAS BUILDS NORTHWARD INTO OUR REGION. THE
AXIS OF THE UPPER TROF CROSS OUR AREA TUESDAY INTO TUESDAY NIGHT.
GUSTY NORTHWEST WINDS WILL CONTINUE TUESDAY AS A TIGHT PRESSURE
GRADIENT WILL REMAIN OVER THE REGION THROUGH TUESDAY. THE GFS...NAM
AND HIRESW-ARW SHOWED UPSLOPE SNOW SHOWERS AND SNOW FLURRIES
CONTINUE IN THE WESTERN MOUNTAINS. ADDITIONAL LIGHT ACCUMULATIONS
MAY BE POSSIBLE IN THE NORTHWEST UPSLOPE FAVORED LOCATIONS. HIGH
TEMPERATURES TUESDAY WILL RANGE FROM THE UPPER TEENS IN THE
NORTHWEST MOUNTAINS TO THE MID 30S IN THE PIEDMONT. HIGH PRESSURE
CONTINUES TRAVEL EASTWARD TUESDAY NIGHT. TUESDAY NIGHT WILL BE A
VERY COLD NIGHT WITH TEMPERATURES ACROSS THE AREA RANGING FROM THE
SINGLE DIGITS IN THE HIGHER ELEVATIONS TO THE UPPER TEENS ACROSS THE
PIEDMONT. WINDS WILL DECREASE TUESDAY NIGHT...BUT WIND CHILLS WILL
BE COLD WITH SINGLE DIGITS IN THE WEST TO TEENS IN THE EAST.
A WARM FRONT WILL PASS OVER THE REGION WEDNESDAY...AS A COLD FRONT
DROPS SOUTH INTO THE OHIO VALLEY. WEDNESDAY AFTERNOON HIGH
TEMPERATURES WILL AVERAGE 20F COLDER THAN NORMAL WITH READINGS FROM
THE LOWER 30S IN THE MOUNTAINS TO THE LOWER 40S IN THE PIEDMONT.
COLD FRONT APPROACHES FROM THE WEST WEDNESDAY NIGHT. ALLOWED FOR
ISOLATED SNOW SHOWERS ACROSS THE NORTH. LOW TEMPERATURES WEDNESDAY
NIGHT WILL GENERALLY BE FROM AROUND 20 DEGREES TO THE MID 20S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 400 PM EST SUNDAY...
SURGE OF ARCTIC AIR TO INVADE THE REGION INTO THURSDAY. THIS WAS NOT
ADVERTISED A FEW RUNS BACK...BUT GIVEN GENERAL CONSENSUS AMONG THE
MODELS AND A PREVAILING MEAN DEEP MERIDIONAL TROUGH ACROSS THE
EASTERN HALF OF THE U.S...THIS APPEARS TO BE A REASONABLE SOLUTION
AND THUS WILL LEAN IN THIS DIRECTION. HOWEVER...IN TERMS OF
INTENSITY...THIS FINAL ARCTIC SURGE WILL NOT EVEN COME CLOSE TO THE
ONE EARLIER IN THE WEEK. MOISTURE IS LIMITED...BUT SLIGHT CHC TO LOW
CHC POPS FOR UPSLOPE -SHSN ACROSS THE USUAL WESTERN UPSLOPE AREAS OF
THE ALLEGHANYS SEEMS REASONABLE AND HAVE BEEN INCLUDED...WITH NO
MENTION OF POPS EAST OF THE ALLEGHANY FRONT. THE PARENT ARCTIC HIGH
WILL SETTLE OVER THE REGION EARLY SATURDAY...SO BELOW NORMAL
TEMPERATURES SHOULD REMAIN IN PLACE THROUGH SAT MORNING. MODEL TEMPS
IN REASONABLE AGREEMENT THROUGH FRI...BUT FEEL THE GFS MOS IS TOO
QUICK TO SPREAD WARMER RETURN FLOW INTO THE REGION SAT...SO LEANED
TOWARD THE COLDER ECMWF MOS.
BIGGER QUESTIONS REMAIN FOR THE REMAINDER OF THE EXTENDED PERIODS.
AS THE ARCTIC HIGH RETREATS TOWARD THE COAST SAT...THE LONG
AWAITED RETURN TO A LESS AMPLIFIED FLOW PATTERN BEGINS TO EVOLVE.
THE EASTERN U.S. TROUGH IS REPLACED BY A SHORT WAVE RIDGE AS BROAD
MEAN TROUGHING RELOCATES TO THE WESTERN/CENTRAL U.S. THE MAIN
CONCERN FOR THE WEEKEND IS THE TIMING AND ASSOCIATED
WARMING/MOISTENING WITH A STRONG NEGATIVELY TITLED HIGHLY
PROGRESSIVE SHORT WAVE PROGGED TO EJECT OUT OF THE BASE OF THE
MEAN TROUGH INTO THE SOUTHEAST STATES SAT NIGHT-SUN. 12Z ECMWF IN
EXCELLENT AGREEMENT WITH 12Z GFS IN BRINGING THIS SYSTEM THROUGH
OUR REGION SUN AFTERNOON. SUPERBLEND POPS WERE LIKELY TO
CATEGORICAL SUN NIGHT-MON. GIVEN THE ASSOCIATED PVA...AND AMOUNT
OF MOIST/WARM ADVECTION INTO THE REGION...THIS SEEMED REASONABLE.
HOWEVER...NEIGHBORING OFFICES WERE NOT ON BOARD WITH THESE HIGH
VALUES THIS FAR OUT...SO STOPPED AT A MORE REASONABLE 50 PERCENT
VALUE FOR NOW. GIVEN RECENT MODEL RUN-TO-RUN VARIATION...THAT
SEEMED REASONABLE FOR SURE. A SIGNIFICANT WARM UP WILL ENSUE SAT-
SUN...BUT AS NOTED ABOVE...PERHAPS NOT TO THE DEGREE ADVERTISED BY
THE MEX MOS. THUS...HAVE USED A MODEL BLEND FOR SAT- SUN.
AN EVEN MORE SIGNIFICANT NEGATIVELY TILTED UPPER TROUGH APPEARS ON
TRACK FOR THE REGION INTO MON. ECMWF/GFS SHOWING SOME INCREDIBLY
WARM/MOIST AIR FOR THIS TIME OF YEAR SPREADING INTO THE REGION
FROM THE SOUTH BY MON MORNING ON THE HEELS A STRONG LOW-LEVEL SOUTHERLY
JET WITH DEWPOINTS APPROACHING 60 DEGREES BY MON AFTERNOON ACROSS
THE PIEDMONT AND SOUTHSIDE. PROGGED LIFTED INDICES AND CAPES ALONG
WITH EVIDENT SHEAR SUGGEST SOME -TSRA MAY NEED TO BE CONSIDERED BY
MON AFTERNOON ACROSS THE PIEDMONT. TO SAY THE LEAST...EARLY NEXT
WEEK WILL BE IN SHARP CONTRAST TO THE WEATHER EXPECTED THIS WEEK
WITH TEMPERATURES ACTUALLY ABOVE SEASONAL NORMALS...ESPECIALLY IF
LOWS ARE ONLY IN THE 50S MON MORNING WITH HIGHS IN THE 60S.
&&
.AVIATION /16Z MONDAY THROUGH FRIDAY/...
AS OF 640 AM EST MONDAY...
RAINFALL INCREASING OVER THE AREA THIS MORNING AND SHOULD SPREAD
EAST THRU LATE MORNING. AIRPORTS WILL FLUCTUATE IN THE CIGS/VSBYS
WITH MODERATE TO AT TIMES HEAVY RAIN BRING CIGS UP AND VSBYS DOWN
WHILE LIGHTER RAINS ALLOW CIGS TO DROP TO IFR/LIFR.
STRONG LLJ TO INCREASE AT THE TAF START TIME THEN LIFT OUT BY
MIDDAY. INVERSION AT THE SFC WILL ALLOW FOR LIGHT WINDS...SUCH
THAT LOW LVL WIND SHEAR WILL OCCUR AS 2KFT AGL WILL START RUNNING
INTO THE 30-45 KT JET.
LOOK FOR THE RAIN TO DIMINISH IN THE MTNS BY EARLY AFTERNOON WITH
COLDER AIR WORKING IN BY 21-00Z...WITH UPSLOPE SNOW SHOWERS
GETTING GOING. FURTHER EAST THE RAIN SHIELD SHOULD EXIT ROA/BCB BY
19-21Z...LYH/DAN 22Z. WINDS WILL PICK UP FROM THE WNW AND GUST TO
30 TO 40 MPH IN THE MTNS TONIGHT.
CIGS WILL STAY MVFR IN THE MTNS TONIGHT AND VFR EAST.
ARCTIC BLAST OF AIR MAY LEAD TO WATER FREEZING ON
RUNWAYS/AIRPLANES THIS EVENING...THOUGH WINDS MAY LEAD TO QUICKER
EVAPORATION OF THE WET SFCS.
EXTENDED DISCUSSION...
EXPECT MAINLY VFR WEATHER TUESDAY-THURSDAY. NEXT SYSTEM APPEARS TO
ARRIVE FRIDAY WITH MVFR CIGS IN THE MTNS.
&&
.CLIMATE...
AS OF 315 PM EST SUNDAY...
RECORD COOLEST HIGHS...TUESDAY NOV 18TH
BLACKSBURG VA...30 IN 2008
BLUEFIELD WV....27 IN 2008
DANVILLE VA.....38 IN 1959
ROANOKE VA......33 IN 1951
LEWISBURG WV....30 IN 2008
LYNCHBURG VA....32 IN 1924
&&
.EQUIPMENT...
AS OF 120 AM EST MONDAY...
KFCX RADAR DOWN DUE TO TRANSMITTER FAULT. TECHNICIANS WILL WORK ON
RESTORING THIS BY NOON TODAY.
THE VISIBILITY SENSOR AT KLYH...LYNCHBURG AIRPORT...WILL BE OUT
OF SERVICE UNTIL MONDAY WHEN TECHNICIANS WILL REPLACE THE SENSOR.
UNTIL THEN THE VISIBILITY WILL ONLY BE REPORTED WHEN THE CONTROL
TOWER IS STAFFED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EST
TUESDAY FOR VAZ015.
NC...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EST
TUESDAY FOR NCZ001-018.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...SMR/RCS/WP
SHORT TERM...KK
LONG TERM...RAB
AVIATION...WP
CLIMATE...RCS
EQUIPMENT...WERT/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
654 AM EST MON NOV 17 2014
.SYNOPSIS...
A STRONG COLD FRONT SWINGS ACROSS THE AREA TODAY. ARCTIC AIR WILL
FOLLOW TONIGHT WITH HIGH PRESSURE MOVING INTO THE MID MISSISSIPPI
VALLEY. EXPECT A PERIOD OF SNOW SHOWERS...WINDS AND COLD WIND
CHILLS LATE TONIGHT INTO TUESDAY MORNING AS A RESULT.
HIGH PRESSURE BUILDS ACROSS THE SOUTHEAST INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM EST MONDAY...
RADAR STARTING TO FILL IN OVER THE MTNS THIS MORNING. FORECAST ON
TRACK...SO NO MAJOR CHANGES WITH UPDATE...EXCEPT WITH WARMER TEMPS
IN THE FAR SW VA AREA.
PREVIOUS DISCUSSION...
EARLIER RUN OF THE HRRR HAD A GREAT HANDLE ON THE RAIN MOVING IN
FROM THE SOUTHWEST. FOLLOWED ITS SOLUTION THROUGH THE
MORNING...BLENDING IN THE 00Z GFS/NAM. LOOKS LIKE A SLAM DUNK FOR
EVERYONE SEEING RAIN TODAY...THOUGH AMOUNTS MAY BE LESS THAN EARLIER
THOUGHT AS DID NOT SEE AS MUCH FALL SUNDAY.
STILL A GOOD ONE HALF TO THREE QUARTERS OF AN INCH WILL OCCUR TODAY.
THIS FRONT LOCATED ACROSS THE CENTRAL APPALACHIANS SOUTHWEST INTO
ALABAMA WILL SLIDE EAST ACROSS THE AREA TODAY...WITH A COUPLE WAVES
OF LOW PRESSURE ALONG IT. THE MAIN FORECAST ISSUE WILL BE THE COLDER
AIR ARRIVING BEHIND THE FRONT. THE 00Z NAM DEPICTED THE COLDER AIR
BETTER AT 06Z AT 8H THAN THE GFS/ECMWF...SO LEANED TOWARD IT TEMP
FORECAST. SHOULD SEE DEEP MOISTURE EDGE EAST EARLY THIS AFTERNOON IN
THE MTNS WHILE THE COLDER AIR STARTS TURNING RESIDUAL SHOWERS OVER
TO SNOW LATER IN THE AFTERNOON. BY DUSK MOST OF THE EASTERN HALF OF
THE CWA WILL BE DRYING OUT AS WINDS TURN WNW. TEMPS DESPITE THE
RAIN...OR REALLY AS A RESULT OF THE RAIN BRINGING DOWN THE WARMER
TEMPS ALOFT MAY BRING READINGS INTO THE 50S BEFORE THE COLD AIR
ARRIVES IN THE PIEDMONT THIS AFTERNOON. IN THE MTNS HIGHS SHOULD BE
OCCURRING BY MIDDAY THEN DROPPING IN THE LATE AFTERNOON.
FORECAST SOUNDINGS IN THE MTNS SHOW MOISTURE BECOMING SHALLOW
FAST...WITH THE FAVORABLE SNOW GROWTH TEMPS ALOFT NOT BEING REALIZED
UNTIL LATE EVENING...SO COULD BE SOME PATCHY FREEZING DRIZZLE
ISSUES...AND WILL ADVERTISE THIS IN THE MTNS OF THE FAR WEST THIS
EVENING. THIS HERE LIES THE PROBLEM...WHERE IT RAINS...COMBINED WITH
ARCTIC AIR ARRIVING AND SNIZZLE(SNOW AND FREEZING DRIZZLE)
FOLLOWING...ROADS WILL BECOME SLICK IN THE HIGHER ELEVATIONS BY LATE
DUSK. AFTER COLLABORATING WITH NEIGHBORING OFFICES...IT WAS DECIDED
TO GO WITH A WINTER WX ADVISORY FOR THE NC MTNS INTO THE GRAYSON
HIGHLANDS...BUT TO DELAY ANY HEADLINES...IF THEY ARE NEEDED FURTHER
NORTH INTO THE MTN EMPIRE OF SW VA AND SE WV MTNS. STILL THINK THE
TEMPS FALLING FAST LATE TONIGHT MAY REQUIRE AT LEAST A SPECIAL WX
STATEMENT. THE SNOWFALL ACCUMULATION WILL BE LIGHT GIVEN THE LIMITED
MOISTURE BUT 1 TO 3 INCHES IN THE WESTERN SLOPES ARE POSSIBLE INTO
TUESDAY MORNING.
IN ADDITION...THE WINDS WILL BE GUSTING OVER 40 MPH WITH 6 HR
PRESSURE RISES OF 5-7MB EXPECTED BEHIND THE FRONT THIS EVENING INTO
TUESDAY MORNING. THIS WAS ADDED TO THE WINTER WX ADVISORY IN THE NC
MTNS. CLOUDS MAY PREVENT IDEAL MIXING OF THE STRONGER WINDS
ALOFT...BUT WHERE IT THE CLOUD/CLEARING LINE IS ALONG/NEAR THE BLUE
RIDGE...THINK AN OCCASIONAL 50 MPH GUST WILL BE REALIZED. OUTSIDE
THE WINTER WX ADVISORY FOR ELEVATIONS ABOVE 3000 FT...HIGHLIGHT
WEATHER IN THE HAZARDOUS WEATHER OUTLOOK. WILL TAKE A LOOK AT MORE
DATA COMING IN AND FURTHER COORDINATING WITH OTHER WFO OFFICES TO
SEE IF MORE HEADLINES ARE NEEDED.
FOR TONIGHT...TEMPS WILL DROP INTO THE TEENS MOUNTAINS...SOME SINGLE
DIGITS HIGHEST ELEVATIONS...WITH 20S IN THE EAST. WIND CHILLS BY
DAWN TUESDAY WILL RANGE FROM 5 ABOVE TO 5 BELOW IN THE
MOUNTAINS...TO THE TEENS IN THE EAST.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 315 AM EST MONDAY...
COLD FRONT PUSHES OUT INTO THE ATLANTIC OCEAN TUESDAY AS THE 1033
SURFACE HIGH PRESSURE IN TEXAS BUILDS NORTHWARD INTO OUR REGION. THE
AXIS OF THE UPPER TROF CROSS OUR AREA TUESDAY INTO TUESDAY NIGHT.
GUSTY NORTHWEST WINDS WILL CONTINUE TUESDAY AS A TIGHT PRESSURE
GRADIENT WILL REMAIN OVER THE REGION THROUGH TUESDAY. THE GFS...NAM
AND HIRESW-ARW SHOWED UPSLOPE SNOW SHOWERS AND SNOW FLURRIES
CONTINUE IN THE WESTERN MOUNTAINS. ADDITIONAL LIGHT ACCUMULATIONS
MAY BE POSSIBLE IN THE NORTHWEST UPSLOPE FAVORED LOCATIONS. HIGH
TEMPERATURES TUESDAY WILL RANGE FROM THE UPPER TEENS IN THE
NORTHWEST MOUNTAINS TO THE MID 30S IN THE PIEDMONT. HIGH PRESSURE
CONTINUES TRAVEL EASTWARD TUESDAY NIGHT. TUESDAY NIGHT WILL BE A
VERY COLD NIGHT WITH TEMPERATURES ACROSS THE AREA RANGING FROM THE
SINGLE DIGITS IN THE HIGHER ELEVATIONS TO THE UPPER TEENS ACROSS THE
PIEDMONT. WINDS WILL DECREASE TUESDAY NIGHT...BUT WIND CHILLS WILL
BE COLD WITH SINGLE DIGITS IN THE WEST TO TEENS IN THE EAST.
A WARM FRONT WILL PASS OVER THE REGION WEDNESDAY...AS A COLD FRONT
DROPS SOUTH INTO THE OHIO VALLEY. WEDNESDAY AFTERNOON HIGH
TEMPERATURES WILL AVERAGE 20F COLDER THAN NORMAL WITH READINGS FROM
THE LOWER 30S IN THE MOUNTAINS TO THE LOWER 40S IN THE PIEDMONT.
COLD FRONT APPROACHES FROM THE WEST WEDNESDAY NIGHT. ALLOWED FOR
ISOLATED SNOW SHOWERS ACROSS THE NORTH. LOW TEMPERATURES WEDNESDAY
NIGHT WILL GENERALLY BE FROM AROUND 20 DEGREES TO THE MID 20S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 400 PM EST SUNDAY...
SURGE OF ARCTIC AIR TO INVADE THE REGION INTO THURSDAY. THIS WAS NOT
ADVERTISED A FEW RUNS BACK...BUT GIVEN GENERAL CONSENSUS AMONG THE
MODELS AND A PREVAILING MEAN DEEP MERIDIONAL TROUGH ACROSS THE
EASTERN HALF OF THE U.S...THIS APPEARS TO BE A REASONABLE SOLUTION
AND THUS WILL LEAN IN THIS DIRECTION. HOWEVER...IN TERMS OF
INTENSITY...THIS FINAL ARCTIC SURGE WILL NOT EVEN COME CLOSE TO THE
ONE EARLIER IN THE WEEK. MOISTURE IS LIMITED...BUT SLIGHT CHC TO LOW
CHC POPS FOR UPSLOPE -SHSN ACROSS THE USUAL WESTERN UPSLOPE AREAS OF
THE ALLEGHANYS SEEMS REASONABLE AND HAVE BEEN INCLUDED...WITH NO
MENTION OF POPS EAST OF THE ALLEGHANY FRONT. THE PARENT ARCTIC HIGH
WILL SETTLE OVER THE REGION EARLY SATURDAY...SO BELOW NORMAL
TEMPERATURES SHOULD REMAIN IN PLACE THROUGH SAT MORNING. MODEL TEMPS
IN REASONABLE AGREEMENT THROUGH FRI...BUT FEEL THE GFS MOS IS TOO
QUICK TO SPREAD WARMER RETURN FLOW INTO THE REGION SAT...SO LEANED
TOWARD THE COLDER ECMWF MOS.
BIGGER QUESTIONS REMAIN FOR THE REMAINDER OF THE EXTENDED PERIODS.
AS THE ARCTIC HIGH RETREATS TOWARD THE COAST SAT...THE LONG
AWAITED RETURN TO A LESS AMPLIFIED FLOW PATTERN BEGINS TO EVOLVE.
THE EASTERN U.S. TROUGH IS REPLACED BY A SHORT WAVE RIDGE AS BROAD
MEAN TROUGHING RELOCATES TO THE WESTERN/CENTRAL U.S. THE MAIN
CONCERN FOR THE WEEKEND IS THE TIMING AND ASSOCIATED
WARMING/MOISTENING WITH A STRONG NEGATIVELY TITLED HIGHLY
PROGRESSIVE SHORT WAVE PROGGED TO EJECT OUT OF THE BASE OF THE
MEAN TROUGH INTO THE SOUTHEAST STATES SAT NIGHT-SUN. 12Z ECMWF IN
EXCELLENT AGREEMENT WITH 12Z GFS IN BRINGING THIS SYSTEM THROUGH
OUR REGION SUN AFTERNOON. SUPERBLEND POPS WERE LIKELY TO
CATEGORICAL SUN NIGHT-MON. GIVEN THE ASSOCIATED PVA...AND AMOUNT
OF MOIST/WARM ADVECTION INTO THE REGION...THIS SEEMED REASONABLE.
HOWEVER...NEIGHBORING OFFICES WERE NOT ON BOARD WITH THESE HIGH
VALUES THIS FAR OUT...SO STOPPED AT A MORE REASONABLE 50 PERCENT
VALUE FOR NOW. GIVEN RECENT MODEL RUN-TO-RUN VARIATION...THAT
SEEMED REASONABLE FOR SURE. A SIGNIFICANT WARM UP WILL ENSUE SAT-
SUN...BUT AS NOTED ABOVE...PERHAPS NOT TO THE DEGREE ADVERTISED BY
THE MEX MOS. THUS...HAVE USED A MODEL BLEND FOR SAT- SUN.
AN EVEN MORE SIGNIFICANT NEGATIVELY TILTED UPPER TROUGH APPEARS ON
TRACK FOR THE REGION INTO MON. ECMWF/GFS SHOWING SOME INCREDIBLY
WARM/MOIST AIR FOR THIS TIME OF YEAR SPREADING INTO THE REGION
FROM THE SOUTH BY MON MORNING ON THE HEELS A STRONG LOW-LEVEL SOUTHERLY
JET WITH DEWPOINTS APPROACHING 60 DEGREES BY MON AFTERNOON ACROSS
THE PIEDMONT AND SOUTHSIDE. PROGGED LIFTED INDICES AND CAPES ALONG
WITH EVIDENT SHEAR SUGGEST SOME -TSRA MAY NEED TO BE CONSIDERED BY
MON AFTERNOON ACROSS THE PIEDMONT. TO SAY THE LEAST...EARLY NEXT
WEEK WILL BE IN SHARP CONTRAST TO THE WEATHER EXPECTED THIS WEEK
WITH TEMPERATURES ACTUALLY ABOVE SEASONAL NORMALS...ESPECIALLY IF
LOWS ARE ONLY IN THE 50S MON MORNING WITH HIGHS IN THE 60S.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 640 AM EST MONDAY...
RAINFALL INCREASING OVER THE AREA THIS MORNING AND SHOULD SPREAD
EAST THRU LATE MORNING. AIRPORTS WILL FLUCTUATE IN THE CIGS/VSBYS
WITH MODERATE TO AT TIMES HEAVY RAIN BRING CIGS UP AND VSBYS DOWN
WHILE LIGHTER RAINS ALLOW CIGS TO DROP TO IFR/LIFR.
STRONG LLJ TO INCREASE AT THE TAF START TIME THEN LIFT OUT BY
MIDDAY. INVERSION AT THE SFC WILL ALLOW FOR LIGHT WINDS...SUCH
THAT LOW LVL WIND SHEAR WILL OCCUR AS 2KFT AGL WILL START RUNNING
INTO THE 30-45 KT JET.
LOOK FOR THE RAIN TO DIMINISH IN THE MTNS BY EARLY AFTERNOON WITH
COLDER AIR WORKING IN BY 21-00Z...WITH UPSLOPE SNOW SHOWERS
GETTING GOING. FURTHER EAST THE RAIN SHIELD SHOULD EXIT ROA/BCB BY
19-21Z...LYH/DAN 22Z. WINDS WILL PICK UP FROM THE WNW AND GUST TO
30 TO 40 MPH IN THE MTNS TONIGHT.
CIGS WILL STAY MVFR IN THE MTNS TONIGHT AND VFR EAST.
ARCTIC BLAST OF AIR MAY LEAD TO WATER FREEZING ON
RUNWAYS/AIRPLANES THIS EVENING...THOUGH WINDS MAY LEAD TO QUICKER
EVAPORATION OF THE WET SFCS.
EXTENDED DISCUSSION...
EXPECT MAINLY VFR WEATHER TUESDAY-THURSDAY. NEXT SYSTEM APPEARS TO
ARRIVE FRIDAY WITH MVFR CIGS IN THE MTNS.
&&
.CLIMATE...
AS OF 315 PM EST SUNDAY...
RECORD COOLEST HIGHS...TUESDAY NOV 18TH
BLACKSBURG VA...30 IN 2008
BLUEFIELD WV....27 IN 2008
DANVILLE VA.....38 IN 1959
ROANOKE VA......33 IN 1951
LEWISBURG WV....30 IN 2008
LYNCHBURG VA....32 IN 1924
&&
.EQUIPMENT...
AS OF 120 AM EST MONDAY...
KFCX RADAR DOWN DUE TO TRANSMITTER FAULT. TECHNICIANS WILL WORK ON
RESTORING THIS BY NOON TODAY.
THE VISIBILITY SENSOR AT KLYH...LYNCHBURG AIRPORT...WILL BE OUT
OF SERVICE UNTIL MONDAY WHEN TECHNICIANS WILL REPLACE THE SENSOR.
UNTIL THEN THE VISIBILITY WILL ONLY BE REPORTED WHEN THE CONTROL
TOWER IS STAFFED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EST
TUESDAY FOR VAZ015.
NC...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EST
TUESDAY FOR NCZ001-018.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...WP
SHORT TERM...KK
LONG TERM...RAB
AVIATION...WP
CLIMATE...RCS
EQUIPMENT...WERT/WP
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1251 PM EST MON NOV 17 2014
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO LIFT NORTH OF AREA LATE THIS
MORNING... FOLLOWED BY THE PASSAGE OF A STRONG COLD FRONT FROM THE
WEST LATE TODAY AND EARLY THIS EVENING. COLD ARCTIC HIGH PRESSURE
WILL THEN BUILD OVER THE AREA INTO THE MIDDLE OF THE WEEK...THEN
PREVAIL INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE PRIMARY CONCERN IS THE POTENTIAL FOR SEVERE WEATHER THIS
AFTERNOON AS A POTENT COLD FRONT PUSHES THROUGH LATE IN THE DAY. A
TORNADO WATCH IS IN EFFECT UNTIL 6 PM FOR ALL OF SOUTHEAST SC AND
SOUTHEAST GA. A VERY WARM...MOIST AND MODERATELY UNSTABLE
ENVIRONMENT HAS DEVELOPED ACROSS THE AREA IN WAKE OF A WARM FRONT
THAT LIFTED THROUGH EARLIER THIS MORNING. DESPITE EXTENSIVE CLOUD
COVER...TEMPERATURES HAVE ALREADY WARMED INTO THE MID AND UPPER
70S ALONG THE COASTAL CORRIDOR OF SOUTHEAST SOUTH CAROLINA AND
SOUTHEAST GEORGIA...AND COULD BRIEFLY CLIMB INTO THE LOWER 80S IN
SOME PLACES IN NORTH COASTAL GEORGIA EARLY THIS AFTERNOON WITH
COMPRESSIONAL HEATING AND A STRONG SOUTH-SOUTHWEST FLOW AHEAD OF
THE COLD FRONT. MEANWHILE DEW POINTS ACROSS THE AREA HAVE SURGED
INTO THE UPPER 60S AND LOWER 70S.
THE PRIMARY BAND OF CONVECTION AHEAD OF THE FRONT HAS ALREADY
ENTERED WESTERN PORTIONS OF THE FORECAST AREA...AND WILL PROGRESS
TOWARD THE I-95 CORRIDOR AROUND 2 PM...BEFORE PUSHING OFF THE
SOUTH CAROLINA COAST AROUND 4 PM. THIS AREA OF CONVECTION WAS
RESPONSIBLE FOR PRODUCING SEVERAL TORNADOES UPSTREAM ACROSS THE FL
PANHANDLE AND SOUTHWEST GA. THE MODE OF CONVECTION HAS CLEARLY
SHIFTED FROM THE DISCRETE SUPERCELLS SEEN EARLIER UPSTREAM...TO
MORE LINEAR SEGMENTS DUE TO THE LOW LEVEL FLOW BECOMING MORE
UNIDIRECTIONAL. WIND SHEAR WILL REMAIN IMPRESSIVE HOWEVER...WITH
THE HRRR SOUNDINGS AT KSAV DEPICTING 0-1KM SHEAR VALUES OF 27 KT
AND 0-3KM SHEAR VALUES OF 43 KT DUE TO A POTENT LOW LEVEL JET
ALOFT. IN ORDER TO TAP INTO THESE WINDS HOWEVER...SUFFICIENT
INSTABILITY IS NEEDED TO SUPPORT DEEP UPDRAFTS/DOWNDRAFTS...AND IT
APPEARS THAT WE MAY ATTAIN CAPE VALUES UP AROUND 1000 J/KG THIS
AFTERNOON BASED ON THE LATEST HIGH RESOLUTION MODEL SOUNDINGS.
GIVEN THESE VALUES...IT APPEARS THE AREA IS PRIMED FOR A POTENTIAL
HIGH SHEAR LOW CAPE SEVERE WEATHER EVENT...SUPPORTED BY SHERB
VALUES OF 1.0 TO 1.2 ACROSS MUCH OF THE AREA. WHILE THE PRIMARY
SEVERE WEATHER THREAT IS DAMAGING WINDS...THERE IS CERTAINLY THE
POTENTIAL FOR AN ISOLATED TORNADO OR TWO TO OCCUR. THE HIGHEST
SEVERE WEATHER PROBABILITIES WILL ALSO OCCUR ACROSS SOUTHEAST
GEORGIA WHERE TEMPERATURES/INSTABILITY WILL BE GREATEST.
THE COLD FRONT WILL BLAST THROUGH LATE TODAY AND EARLY THIS
EVENING WITH CONVECTIVE RAINS SHIFTING QUICKLY OFF THE COAST
SHORTLY AFTER SUNSET THEN COLD AIR WILL COME POURING IN ON THE
HEELS OF STRONG PRES RISES. NEAR FREEZING TEMPS ARE LIKELY IN
WESTERN GEORGIA AREAS AND BORDERING THE FAR SE MIDLANDS AND CSRA
BUT WE HAVE HIGHLIGHTED THE BIG EVENT FOR WEDNESDAY MORNING WITH A
FREEZE WATCH TO ALERT FOR SUB-FREEZING TEMPS ALL THE WAY TO THE
OCEAN...A VERY RARE EVENT FOR MID NOVEMBER ON BEACHES AND BARRIER
ISLANDS.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
TUESDAY AND TUESDAY NIGHT...STRONG COLD ADVECTION WILL BE ONGOING
DURING TUESDAY IN THE WAKE OF THE ARCTIC FRONT. DOWNSLOPE WEST TO
NORTHWEST WINDS WILL SOMEWHAT TEMPER THE IMPACT ON TEMPERATURES.
EVEN SO...LOW LEVEL THICKNESS VALUES WITH FULL SUN SUPPORT HIGHS
ONLY FROM THE UPPERS 40S IN THE NORTHWEST TO LOWER 50S IN THE
EXTREME SOUTHEAST. MAINTAINED HIGHS FROM THE NEAR 50 IN MOST AREAS.
THE STAGE IS SET FOR A WIDESPREAD HARD FREEZE FOR ALL AREAS TUESDAY
NIGHT...WITH LIKELY RECORD BREAKING TEMPERATURES AT ALL THREE
CLIMATE SITES. THIS WILL BE THE COLDEST IT HAS BEEN IN MANY AREAS
SINCE JANUARY 25TH 2014. CLEAR SKIES AND VERY LOW DEWPOINTS COMBINED
WITH DIMINISHING WINDS WILL SET THE STAGE FOR DECENT RADIATIONAL
COOLING ACROSS INLAND AREAS. LATEST MODEL GUIDANCE SUGGEST LIGHT
NORTH WINDS ALONG THE IMMEDIATE COAST WHICH SHOULD ALLOW SUB
FREEZING TEMPERATURES TO REACH ALL BEACHES. LOOKS LIKE 10 TO 13
HOURS OF SUBFREEZING TEMPERATURES WILL OCCUR ACROSS FAR INLAND AREAS
RANGING TO 2 TO 4 HOURS AT THE GEORGIA BEACHES. HAVE ISSUED A FREEZE
WATCH FOR ALL AREAS FOR TUESDAY NIGHT. SINCE LOW TEMPERATURES ARE
EXPECTED TO BE WELL BELOW FREEZING FOR MANY HOURS...PRECAUTIONS NEED
TO BE TAKEN TO PROTECT EXPOSED PIPES.
WEDNESDAY THROUGH THURSDAY...AFTER A FRIGID START ON WEDNESDAY
MORNING...ABUNDANT SUNSHINE WILL HELP TEMPERATURES RECOVER TO NEAR
50 DEGREES IN MANY AREAS. WITH THE HIGH PRESSURE CENTERED NEAR THE
AREA...WINDS WILL BE LIGHT...SO THERE WILL NOT BE ANY DOWNSLOPE FLOW
TO HELP MODERATE TEMPERATURES MORE QUICKLY. A GOOD RADIATIONAL
COOLING NIGHT IS EXPECTED WEDNESDAY NIGHT ACROSS THE AREA.
HOWEVER...INCREASING LOW LEVEL THICKNESS VALUES AND HIGHER DEWPOINTS
THAN TUESDAY NIGHT WILL KEEP TEMPERATURES FROM FALLING TO TUESDAY
NIGHTS LEVELS. EXPECT FREEZING TEMPERATURES IN MOST AREAS...WITH
LOWS IN THE MID TO UPPER 20S INLAND TO THE MID 30S NEAR THE COAST.
IN ALL LIKELIHOOD FREEZING TEMPERATURES WILL OCCUR IN ALL AREAS
TUESDAY NIGHT WHICH SHOULD EFFECTIVELY END THE GROWING SEASON. AS A
RESULT...IT IS HIGHLY LIKELY THAT NO FREEZE WATCHES OR WARNINGS WILL
BE ISSUED FOR WEDNESDAY NIGHT UNLESS FREEZING TEMPERATURES DO NOT
OCCUR EVERYWHERE TUESDAY NIGHT. A MODERATING TREND BEGINS ON
THURSDAY. ABUNDANT SUNSHINE AND INCREASING LOW LEVEL THICKNESS
VALUES SUPPORT HIGH TEMPERATURES IN MOST AREA NEAR 60 DEGREES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
DECENT CONFIDENCE IN A GENERAL MODERATING TREND DURING THIS
PERIOD...WITH HIGH TEMPERATURES CLIMBING TO NEAR OR PERHAPS EVEN
ABOVE NORMAL VALUES BY SUNDAY AND LIKELY TO ABOVE NORMAL LEVELS BY
MONDAY. GOOD AGREEMENT BETWEEN ECMWF AND GFS THAT THE AREA WILL
LIKELY REMAIN RAIN FREE THROUGH SATURDAY. MODEL DIFFERENCES BECOME
QUITE PRONOUNCED BY SUNDAY AND MONDAY...BUT IT DOES APPEAR THAT THE
WEATHER WILL GET MORE UNSETTLED THEN AND AT LEAST FOR NOW INCLUDED
SLIGHT CHANCES FOR RAIN SHOWERS SUNDAY THROUGH MONDAY.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
A LINE OF SHOWERS AND THUNDERSTORMS AHEAD OF A COLD FRONT WILL
AFFECT THE TERMINALS IN THE 19-21Z TIME FRAME. MODERATE TO HEAVY
THUNDERSTORMS WILL RESULT IN FLIGHT RESTRICTIONS DUE TO REDUCED
VISIBILITIES AND LOW CEILINGS. GUSTY AND ERRATIC WINDS ARE ALSO
EXPECTED AS THE CONVECTION SHIFTS ACROSS THE TERMINALS. ONCE THE
SHOWERS AND THUNDERSTORMS SHIFT OFFSHORE LATE THIS
AFTERNOON...SKIES WILL BEGIN CLEARING BUT GUSTY WEST-NORTHWEST
WINDS WILL CONTINUE INTO TUESDAY MORNING.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL PREVAIL.
&&
.MARINE...
OTHERWISE INCREASING LOW LEVEL JET AND WARM AIR ADVECTION BOTH
IMPRESSIVE TODAY BUT THE MIXING PROFILES ARE QUITE POOR CLOSE TO
SHORE AS SEA SURFACE TEMPS ARE CLOSER TO 60F. THE LAND/SEA
INTERFACE SHOULD BECOME GUSTY BY EARLY AFTERNOON AND ALLOWED AN
SCA TO CONTINUE NORTH OF SAVANNAH TODAY.
THE TWO MOST SIGNIFICANT ISSUES WILL BE CONVECTION LATER TODAY
AND POSSIBLE GALES OVER THE GEORGIA WATERS TONIGHT. THE CONVECTION
WILL PRODUCE A RISK OF WIND GUSTS OVER 35 KT AND POSSIBLE WATERSPOUTS
ESPECIALLY OVER WATERS SEAWARD FROM THE PILOT BUOYS. THE TIMING
LOOKS TO BE MID AFTERNOON THROUGH EARLY EVENING.
THE GALE RISK WAS HIGH ENOUGH THIS MORNING TO HOIST A GALE WATCH
TONIGHT FOR THE OUTER GEORGIA WATERS. GRAYS REEF COULD SEE A
PERIOD OF GALE FORCE GUSTS FROM LATE EVENING TO 6 AM AS JETTING
AND LOW LEVEL MOMENTUM PROGS ARE EXTREMELY FAVORABLE GIVEN THE
SHARP ISALLOBARIC RISES ANTICIPATED. OTHER WATERS WILL BE IN SMALL
CRAFT ADVISORY CONDITIONS TONIGHT.
TUESDAY THROUGH FRIDAY...HIGH PRESSURE WILL BUILD FROM THE WEST ON
TUESDAY...WITH IMPROVING CONDITIONS ON THE WATERS. SMALL CRAFT
ADVISORIES FOR AMZ352 AND AMZ354 ARE EXPECTED TO END TUESDAY
MORNING. ANY GALE CONDITIONS ACROSS AMZ374 SHOULD END EARLY ON
TUESDAY WITH SMALL CRAFT ADVISORY CONDITIONS THEN PERSISTING INTO
TUESDAY NIGHT. IMPROVING CONDITIONS WILL THEN CONTINUE ACROSS ALL
WATERS AS HIGH PRESSURE SETTLES OVER THE REGION. WINDS MAINLY AOB 10
KNOTS AND SEAS 1 TO 3 FEET ARE EXPECTED FROM WEDNESDAY MORNING INTO
THURSDAY NIGHT AND POSSIBLY EVEN FRIDAY MORNING.
&&
.CLIMATE...
RECORD LOW MAXIMUM TEMPERATURES FOR NOVEMBER 18TH...
KCHS...49 SET IN 2008.
KCHL...48 SET IN 1951.
KSAV...45 SET IN 1891.
RECORD LOWS FOR NOVEMBER 19TH...
KCHS...27 SET IN 1949.
KCHL...31 SET IN 1903.
KSAV...27 SET IN 2008 AND PREVIOUS.
RECORD LOW MAXIMUM TEMPERATURES FOR NOVEMBER 19TH...
KCHS...44 SET IN 2000.
KCHL...45 SET IN 1951.
KSAV...44 SET IN 2000.
RECORD LOW FOR SO EARLY IN THE SEASON...
KCHS...22 NOVEMBER 16 1940.
KCHL...28 NOVEMBER 16 1940.
KSAV...24 NOVEMBER 3 1954.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING
FOR GAZ087-088-099>101-114>119-137>141.
SC...FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING
FOR SCZ040-042>045-047>052.
LAKE WIND ADVISORY UNTIL 6 AM EST TUESDAY FOR SCZ045.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST TUESDAY FOR AMZ352.
SMALL CRAFT ADVISORY UNTIL 6 AM EST TUESDAY FOR AMZ330-350.
SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO NOON EST
TUESDAY FOR AMZ354.
GALE WATCH FROM 7 PM EST THIS EVENING THROUGH TUESDAY MORNING
FOR AMZ374.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR AMZ374.
&&
$$
NEAR TERM...JAQ
SHORT TERM...MTE
LONG TERM...MTE
AVIATION...JAQ/MTE
MARINE...MTE
CLIMATE...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1135 AM EST MON NOV 17 2014
...SEVERE WEATHER THREAT THIS AFTERNOON...
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO LIFT NORTH OF AREA LATE THIS
MORNING... FOLLOWED BY THE PASSAGE OF A STRONG COLD FRONT FROM THE
WEST LATE TODAY AND EARLY THIS EVENING. COLD ARCTIC HIGH PRESSURE
WILL THEN BUILD OVER THE AREA INTO THE MIDDLE OF THE WEEK...THEN
PREVAIL INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE PRIMARY CONCERN IS THE POTENTIAL FOR SEVERE WEATHER THIS
AFTERNOON AS A POTENT COLD FRONT PUSHES THROUGH LATE IN THE DAY. A
TORNADO WATCH IS IN EFFECT UNTIL 6 PM FOR ALL OF SOUTHEAST SC AND
SOUTHEAST GA. A VERY WARM...MOIST AND MODERATELY UNSTABLE
ENVIRONMENT HAS DEVELOPED ACROSS THE AREA IN WAKE OF A WARM FRONT
THAT LIFTED THROUGH EARLIER THIS MORNING. DESPITE EXTENSIVE CLOUD
COVER...TEMPERATURES HAVE ALREADY WARMED INTO THE MID AND UPPER
70S ALONG THE COASTAL CORRIDOR OF SOUTHEAST SOUTH CAROLINA AND
SOUTHEAST GEORGIA...AND COULD CLIMB INTO THE LOWER 80S IN SOME
PLACES IN NORTH COASTAL GEORGIA BY EARLY AFTERNOON WITH
COMPRESSIONAL HEATING AND A STRONG SOUTH-SOUTHWEST FLOW AHEAD OF
THE COLD FRONT. MEANWHILE DEW POINTS ACROSS THE AREA HAVE SURGED
INTO THE UPPER 60S AND LOWER 70S.
THE PRIMARY BAND OF CONVECTION AHEAD OF THE FRONT IS EXPECTED TO
ENTER WESTERN PORTIONS OF THE FORECAST AREA AROUND NOON...THEN
PROGRESS TOWARD THE I-95 CORRIDOR AROUND 2 PM...BEFORE PUSHING OFF
THE SOUTH CAROLINA COAST AROUND 4 PM. THIS AREA OF CONVECTION WAS
RESPONSIBLE FOR PRODUCING SEVERAL TORNADOES UPSTREAM ACROSS THE
FL PANHANDLE AND SOUTHWEST GA. AS THE STORMS SHIFT INTO THE
AREA...THE MODE OF CONVECTION WILL SHIFT FROM THE DISCRETE
SUPERCELLS SEEN EARLIER UPSTREAM...TO MORE LINEAR SEGMENTS AS THE
LOW LEVEL FLOW BECOMES MORE UNIDIRECTIONAL. WIND SHEAR WILL REMAIN
IMPRESSIVE HOWEVER...WITH THE HRRR SOUNDINGS AT KSAV DEPICTING 0-1KM
SHEAR VALUES OF 27 KT AND 0-3KM SHEAR VALUES OF 43 KT DUE TO A
POTENT LOW LEVEL JET ALOFT. IN ORDER TO TAP INTO THESE WINDS
HOWEVER...SUFFICIENT INSTABILITY IS NEEDED TO SUPPORT DEEP
UPDRAFTS/DOWNDRAFTS...AND IT APPEARS THAT WE MAY ATTAIN CAPE VALUES
UP AROUND 1000 J/KG THIS AFTERNOON BASED ON THE LATEST HIGH
RESOLUTION MODEL SOUNDINGS. GIVEN THESE VALUES...IT APPEARS THE
AREA IS PRIMED FOR A POTENTIAL HIGH SHEAR LOW CAPE SEVERE WEATHER
EVENT...SUPPORTED BY SHERB VALUES OF 1.0 TO 1.2 ACROSS MUCH OF THE
AREA. WHILE THE PRIMARY SEVERE WEATHER THREAT IS DAMAGING
WINDS...THERE IS CERTAINLY THE POTENTIAL FOR AN ISOLATED TORNADO
OR TWO TO OCCUR. THE HIGHEST SEVERE WEATHER PROBABILITIES WILL
ALSO OCCUR ACROSS SOUTHEAST GEORGIA WHERE TEMPERATURES/INSTABILITY
WILL BE GREATEST.
THE COLD FRONT WILL BLAST THROUGH LATE TODAY AND EARLY THIS
EVENING WITH CONVECTIVE RAINS SHIFTING QUICKLY OFF THE COAST
SHORTLY AFTER SUNSET THEN COLD AIR WILL COME POURING IN ON THE
HEELS OF STRONG PRES RISES. NEAR FREEZING TEMPS ARE LIKELY IN
WESTERN GEORGIA AREAS AND BORDERING THE FAR SE MIDLANDS AND CSRA
BUT WE HAVE HIGHLIGHTED THE BIG EVENT FOR WEDNESDAY MORNING WITH A
FREEZE WATCH TO ALERT FOR SUB-FREEZING TEMPS ALL THE WAY TO THE
OCEAN...A VERY RARE EVENT FOR MID NOVEMBER ON BEACHES AND BARRIER
ISLANDS.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
TUESDAY AND TUESDAY NIGHT...STRONG COLD ADVECTION WILL BE ONGOING
DURING TUESDAY IN THE WAKE OF THE ARCTIC FRONT. DOWNSLOPE WEST TO
NORTHWEST WINDS WILL SOMEWHAT TEMPER THE IMPACT ON TEMPERATURES.
EVEN SO...LOW LEVEL THICKNESS VALUES WITH FULL SUN SUPPORT HIGHS
ONLY FROM THE UPPERS 40S IN THE NORTHWEST TO LOWER 50S IN THE
EXTREME SOUTHEAST. MAINTAINED HIGHS FROM THE NEAR 50 IN MOST AREAS.
THE STAGE IS SET FOR A WIDESPREAD HARD FREEZE FOR ALL AREAS TUESDAY
NIGHT...WITH LIKELY RECORD BREAKING TEMPERATURES AT ALL THREE
CLIMATE SITES. THIS WILL BE THE COLDEST IT HAS BEEN IN MANY AREAS
SINCE JANUARY 25TH 2014. CLEAR SKIES AND VERY LOW DEWPOINTS COMBINED
WITH DIMINISHING WINDS WILL SET THE STAGE FOR DECENT RADIATIONAL
COOLING ACROSS INLAND AREAS. LATEST MODEL GUIDANCE SUGGEST LIGHT
NORTH WINDS ALONG THE IMMEDIATE COAST WHICH SHOULD ALLOW SUB
FREEZING TEMPERATURES TO REACH ALL BEACHES. LOOKS LIKE 10 TO 13
HOURS OF SUBFREEZING TEMPERATURES WILL OCCUR ACROSS FAR INLAND AREAS
RANGING TO 2 TO 4 HOURS AT THE GEORGIA BEACHES. HAVE ISSUED A FREEZE
WATCH FOR ALL AREAS FOR TUESDAY NIGHT. SINCE LOW TEMPERATURES ARE
EXPECTED TO BE WELL BELOW FREEZING FOR MANY HOURS...PRECAUTIONS NEED
TO BE TAKEN TO PROTECT EXPOSED PIPES.
WEDNESDAY THROUGH THURSDAY...AFTER A FRIGID START ON WEDNESDAY
MORNING...ABUNDANT SUNSHINE WILL HELP TEMPERATURES RECOVER TO NEAR
50 DEGREES IN MANY AREAS. WITH THE HIGH PRESSURE CENTERED NEAR THE
AREA...WINDS WILL BE LIGHT...SO THERE WILL NOT BE ANY DOWNSLOPE FLOW
TO HELP MODERATE TEMPERATURES MORE QUICKLY. A GOOD RADIATIONAL
COOLING NIGHT IS EXPECTED WEDNESDAY NIGHT ACROSS THE AREA.
HOWEVER...INCREASING LOW LEVEL THICKNESS VALUES AND HIGHER DEWPOINTS
THAN TUESDAY NIGHT WILL KEEP TEMPERATURES FROM FALLING TO TUESDAY
NIGHTS LEVELS. EXPECT FREEZING TEMPERATURES IN MOST AREAS...WITH
LOWS IN THE MID TO UPPER 20S INLAND TO THE MID 30S NEAR THE COAST.
IN ALL LIKELIHOOD FREEZING TEMPERATURES WILL OCCUR IN ALL AREAS
TUESDAY NIGHT WHICH SHOULD EFFECTIVELY END THE GROWING SEASON. AS A
RESULT...IT IS HIGHLY LIKELY THAT NO FREEZE WATCHES OR WARNINGS WILL
BE ISSUED FOR WEDNESDAY NIGHT UNLESS FREEZING TEMPERATURES DO NOT
OCCUR EVERYWHERE TUESDAY NIGHT. A MODERATING TREND BEGINS ON
THURSDAY. ABUNDANT SUNSHINE AND INCREASING LOW LEVEL THICKNESS
VALUES SUPPORT HIGH TEMPERATURES IN MOST AREA NEAR 60 DEGREES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
DECENT CONFIDENCE IN A GENERAL MODERATING TREND DURING THIS
PERIOD...WITH HIGH TEMPERATURES CLIMBING TO NEAR OR PERHAPS EVEN
ABOVE NORMAL VALUES BY SUNDAY AND LIKELY TO ABOVE NORMAL LEVELS BY
MONDAY. GOOD AGREEMENT BETWEEN ECMWF AND GFS THAT THE AREA WILL
LIKELY REMAIN RAIN FREE THROUGH SATURDAY. MODEL DIFFERENCES BECOME
QUITE PRONOUNCED BY SUNDAY AND MONDAY...BUT IT DOES APPEAR THAT THE
WEATHER WILL GET MORE UNSETTLED THEN AND AT LEAST FOR NOW INCLUDED
SLIGHT CHANCES FOR RAIN SHOWERS SUNDAY THROUGH MONDAY.
&&
.AVIATION /16Z MONDAY THROUGH FRIDAY/...
THE DENSE FOG FROM THE OVERNIGHT HAS LIFTED AT KCHS AND HAS BEEN
OUT OF KSAV FOR SEVERAL HOURS. OCCASIONAL MVFR CIGS MAY OCCUR AT
BOTH TERMINALS BEFORE CONVECTION MOVES THROUGH FROM 18Z TO 22Z
TODAY. THERE IS A SMALL CHANCE IT REACHES KSAV BEFORE 18Z GIVEN
SOME OF THE LATEST UPSTREAM RADAR TRENDS. S TO SW WINDS WILL BE
RAMPING UP THIS MORNING AND PRE-FRONTAL TODAY AND SIGNIFICANT
CONVECTIVE WIND GUSTS ARE POSSIBLE IN THE VICINITY OF STRONG
SHOWERS AND TSTMS THIS AFTERNOON. CIGS WILL BE VFR TONIGHT IN
THE WAKE OF THE COLD FRONT WITH SURFACE FLOW FROM THE NW AND
PERIODS OF GUSTINESS ARE LIKELY AT BOTH TERMINALS OVERNIGHT.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL PREVAIL.
&&
.MARINE...
OTHERWISE INCREASING LOW LEVEL JET AND WARM AIR ADVECTION BOTH
IMPRESSIVE TODAY BUT THE MIXING PROFILES ARE QUITE POOR CLOSE TO
SHORE AS SEA SURFACE TEMPS ARE CLOSER TO 60F. THE LAND/SEA
INTERFACE SHOULD BECOME GUSTY BY EARLY AFTERNOON AND ALLOWED AN
SCA TO CONTINUE NORTH OF SAVANNAH TODAY.
THE TWO MOST SIGNIFICANT ISSUES WILL BE CONVECTION LATER TODAY
AND POSSIBLE GALES OVER THE GEORGIA WATERS TONIGHT. THE CONVECTION
WILL PRODUCE A RISK OF WIND GUSTS OVER 35 KT AND POSSIBLE WATERSPOUTS
ESPECIALLY OVER WATERS SEAWARD FROM THE PILOT BUOYS. THE TIMING
LOOKS TO BE EARLY TO MID AFTERNOON THROUGH EARLY EVENING.
THE GALE RISK WAS HIGH ENOUGH THIS MORNING TO HOIST A GALE WATCH
TONIGHT FOR THE OUTER GEORGIA WATERS. GRAYS REEF COULD SEE A
PERIOD OF GALE FORCE GUSTS FROM LATE EVENING TO 6 AM AS JETTING
AND LOW LEVEL MOMENTUM PROGS ARE EXTREMELY FAVORABLE GIVEN THE
SHARP ISALLOBARIC RISES ANTICIPATED. OTHER WATERS WILL BE IN SMALL
CRAFT ADVISORY CONDITIONS TONIGHT.
TUESDAY THROUGH FRIDAY...HIGH PRESSURE WILL BUILD FROM THE WEST ON
TUESDAY...WITH IMPROVING CONDITIONS ON THE WATERS. SMALL CRAFT
ADVISORIES FOR AMZ352 AND AMZ354 ARE EXPECTED TO END TUESDAY
MORNING. ANY GALE CONDITIONS ACROSS AMZ374 SHOULD END EARLY ON
TUESDAY WITH SMALL CRAFT ADVISORY CONDITIONS THEN PERSISTING INTO
TUESDAY NIGHT. IMPROVING CONDITIONS WILL THEN CONTINUE ACROSS ALL
WATERS AS HIGH PRESSURE SETTLES OVER THE REGION. WINDS MAINLY AOB 10
KNOTS AND SEAS 1 TO 3 FEET ARE EXPECTED FROM WEDNESDAY MORNING INTO
THURSDAY NIGHT AND POSSIBLY EVEN FRIDAY MORNING.
&&
.CLIMATE...
RECORD LOW MAXIMUM TEMPERATURES FOR NOVEMBER 18TH...
KCHS...49 SET IN 2008.
KCHL...48 SET IN 1951.
KSAV...45 SET IN 1891.
RECORD LOWS FOR NOVEMBER 19TH...
KCHS...27 SET IN 1949.
KCHL...31 SET IN 1903.
KSAV...27 SET IN 2008 AND PREVIOUS.
RECORD LOW MAXIMUM TEMPERATURES FOR NOVEMBER 19TH...
KCHS...44 SET IN 2000.
KCHL...45 SET IN 1951.
KSAV...44 SET IN 2000.
RECORD LOW FOR SO EARLY IN THE SEASON...
KCHS...22 NOVEMBER 16 1940.
KCHL...28 NOVEMBER 16 1940.
KSAV...24 NOVEMBER 3 1954.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING
FOR GAZ087-088-099>101-114>119-137>141.
SC...FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING
FOR SCZ040-042>045-047>052.
LAKE WIND ADVISORY UNTIL 6 AM EST TUESDAY FOR SCZ045.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST TUESDAY FOR AMZ352.
SMALL CRAFT ADVISORY UNTIL 6 AM EST TUESDAY FOR AMZ330-350.
SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO NOON EST
TUESDAY FOR AMZ354.
GALE WATCH FROM 7 PM EST THIS EVENING THROUGH TUESDAY MORNING
FOR AMZ374.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR AMZ374.
&&
$$
NEAR TERM...JAQ
SHORT TERM...MTE
LONG TERM...MTE
AVIATION...
MARINE...MTE
CLIMATE...
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
259 PM EST MON NOV 17 2014
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE
BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 255 PM EST MON NOV 17 2014
SCATTERED SNOW SHOWERS WILL DEVELOP AND CONTINUE INTO THE EVENING
AS MUCH COLDER AIR SPREADS INTO THE OHIO VALLEY. VERY COLD WEATHER
WILL CONTINUE THROUGH MIDWEEK...WITH CHANCES FOR SNOW AGAIN ON
WEDNESDAY AS A WEAK UPPER LEVEL WAVE PASSES THROUGH THE REGION.
LOW PRESSURE TRACKING INTO THE REGION OVER THE WEEKEND WILL BRING
A RETURN TO UNSETTLED WEATHER ALONG WITH WARMER TEMPERATURES.
&&
.NEAR TERM /REST OF THIS AFTERNOON THROUGH TUESDAY/...
ISSUED AT 255 PM EST MON NOV 17 2014
CLEARLY DEFINED CLOUD STREETS ON THE VISIBLE SATELLITE A FEW HOURS
AGO BEGAN DEVELOPING SNOW SHOWERS AND FLURRIES IN THE LAST HOUR AND
THESE HAVE MADE IT INTO WEST CENTRAL INDIANA. THUS FAR THE IMPACT
SEEMS TO BE VISIBILITIES ONLY AS LOW AS 2-3SM OR WITH NO VISIBILITY
IMPACT AT ALL. BASED ON HRRR AND CONDITIONS UPSTREAM EXPECT THESE
SNOW SHOWERS TO INCREASE IN COVERAGE ACROSS THE AREA AND POSSIBLY IN
INTENSITY. WILL CONTINUE TO CARRY SCATTERED SNOW SHOWERS THROUGH
EARLY THIS EVENING. ONLY CHANGE WAS TO CUT OFF TIMING A LITTLE EARLY
BASED ON LATEST HRRR GUIDANCE. APPEARS THESE CONVECTIVE SNOW SHOWERS
SHOULD BE WANING SIGNIFICANTLY AFTER 00Z...AND TRIED TO DEPICT THIS
IN THE GRIDS. OPTED TO STICK WITH AN SPS TO HANDLE THE SCATTERED
SNOW SHOWERS AND GUSTY WINDS WHICH COULD CAUSE SOME POTENTIAL
TRAVEL CONCERNS...ESPECIALLY FOR THE EVENING COMMUTE. THE HWO AND WX
STORY WILL ALSO REFLECT THE IMPACTS OF LATE AFTERNOON AND EVENING
TRAVEL WX.
LEFT IN CHANCES FOR FLURRIES FOR OVERNIGHT AND TUESDAY
AS ENERGY FROM UPPER LEVEL SYSTEM CONTINUES TO ROTATE THROUGH THE
REGION. BIG STORY THEN TURNS TO TEMPS AS 850MB TEMPS PLUMMET TO
-20-22 TONIGHT. THIS WILL ALLOW LOWS TO GET DOWN TO 7-10 FOR THE CWA
TONIGHT...AND COMBINED WITH THE GUSTY WESTERLY WINDS...WIND CHILLS
WILL BE IN THE 0 TO -10 RANGE BY EARLY TUESDAY MORNING. ALREADY THIS
AFTERNOON CENTRAL INDIANA IS FEELING THE IMPACT OF WIND CHILLS IN
THE LOW TEENS TO SINGLE DIGITS. TUESDAY MAY BREAK THE RECORD FOR LOW
MAXIMUM WITH HIGHS NOT EXPECTED TO GET OUT OF THE LOW 20S.
FORECASTING 19 FOR KIND WITH HIGHS ONLY IN THE HIGH TEENS ACROSS THE
NORTH TO LOW 20S FAR SOUTHERN COUNTIES. AGAIN WE WILL BE PLAGUED
WITH STRONG WINDS THAT WILL MAKE FOR COLD WIND CHILLS EVEN DURING THE
MIDDLE OF THE DAY IN THE SINGLE DIGITS.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 255 PM EST MON NOV 17 2014
FORECAST CONCERNS FOR THE SHORT TERM CONTINUE TO BE SNOW CHANCES ON
WEDNESDAY AND THE MUCH BELOW AVERAGE TEMPERATURES.
THE PERIOD WILL BEGIN DRY AS THE AREA IS SANDWICHED BETWEEN LOW
PRESSURE NEAR THE WESTERN GREAT LAKES AND HIGH PRESSURE ACROSS THE
SOUTHEASTERN CONUS. TEMPERATURES WILL REMAIN WELL BELOW NORMAL FOR
TUESDAY NIGHT. HOWEVER...WITH SOME WARM ADVECTION KICKING IN DURING
THE OVERNIGHT HOURS...READINGS SHOULD STAY OUT OF THE SINGLE DIGITS.
WEAK WARM ADVECTION AHEAD OF A COLD FRONT LOOKS TO ALLOW
TEMPERATURES TO REACH AT LEAST THE FREEZING MARK ON WEDNESDAY...FOR
THE FIRST TIME IN SEVERAL DAYS. ALTHOUGH MOISTURE PROFILES ARE NOT
INCREDIBLY IMPRESSIVE PER MODEL SOUNDINGS...SOME LIGHT SNOW SHOWERS
ARE NOT OUT OF THE QUESTION WITH FRONTAL PASSAGE...MAINLY ACROSS THE
NORTHERN TWO THIRDS OF THE AREA CLOSEST TO THE BEST FORCING
ASSOCIATED WITH AN UPPER WAVE.
DRY CONDITIONS WILL RETURN ON THURSDAY AS SURFACE HIGH PRESSURE
BEGINS TO BUILD INTO THE AREA FROM THE SOUTH.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
ISSUED AT 255 PM EST MON NOV 17 2014
MODEL ENSEMBLES INDICATE WE WILL BE TRANSITIONING FROM COLD AND DRY
WEATHER THURSDAY NIGHT AND FRIDAY...TO MILD AND WET WEATHER BY THE
MIDDLE OF THE WEEKEND ON.
A STRONG UPPER TROUGH OVER THE EAST COAST ON FRIDAY WILL MVOE TO THE
EAST AS MODELS MOVE AN UPPER TROUGH INITIALLY NEAR THE PACIFIC COAST
TO THE UPPER MIDWEST AND CENTRAL PLAINS BY MONDAY. AT THE SURFACE
HIGH PRESSURE WILL BE ACROSS OUR REGION FRIDAY AS A WARM FRONT
DEVELOPS OVER THE SOUTHERN PLAINS INTO THE DEEP SOUTH. MODELS HAVE
TRENDED IN MOVING PRECIPITATION QUICKER OUR WAY IN THE LATEST RUN.
THEY ALL BRING IN SOME PRECIPITATION FRIDAY NIGHT AND INCREASE IT
OVER THE WEEKEND AS STRONG LOW PRESSURE MOVES INTO THE CENTRAL
PLAINS AND EVENTUALLY INTO THE WESTERN GREAT LAKES.
WITH TEMPERATURES WARMING UP...PRECIPITATION TYPE WILL BE A BIG
ISSUE FRIDAY NIGHT INTO SATURDAY. INCREASING LOW LEVEL THICKNESS
ALONG WITH SURFACE TEMPERATURES BELOW 32 INDICATE FREEZING RAIN THE
MOST LIKELY TYPE SOUTH HALF FRIDAY NIGHT AND MOST AREAS SATURDAY
MORNING. WILL MENTION CHANCE OF FREEZING RAIN THOSE AREAS THEN AND
THEN ALL RAIN FROM SATURDAY AFTERNOON ON.
CONCERNING TEMPERATURES...WENT A LITTLE WARMER THAN MOS BLEND FRIDAY
NIGHT AS MODELS BRING IN CLOUDS ALONG WITH WARM ADVECTION.
OTHERWISE...ONLY MINOR TWEAKS MADE TO SUPERBLEND TEMPERATURES MOST
OTHER PERIODS.
&&
.AVIATION /DISCUSSION FOR THE 171800Z TAF ISSUANCE/...
ISSUED AT 1200 PM EST MON NOV 17 2014
MOSTLY MVFR CEILINGS WITH SCATTERED LIGHT SNOW SHOWERS THROUGH THIS
EVENING. THEN VFR LATE TONIGHT UNTIL MIDDAY TUESDAY.
SATELLITE AND WEATHER DEPICTION INDICATED BROKEN TO SCATTERED CLOUDS
AROUND 25 HUNDRED FEET ACROSS THE AREA. WITH STRONG COLD ADVECTION
AIRMASS WILL BECOME MORE UNSTABLE LATE THIS AFTERNOON AND EARLY
TONIGHT AS AN UPPER TROUGH MOVES INTO OUR AREA. SEVERAL HIGH
RESOLUTION MODELS HINT AT DEVELOPMENT OF SNOW SHOWERS WHICH COULD
CAUSE RAPID FLUCTUATION IN VISIBILITIES BY 20Z AND LASTING AT LEAST
THROUGH MIDNIGHT. WILL ADD A PREVAILING 4 MILES AND SNOW SHOWERS
BEGINNING 20Z...ALTHOUGH VISIBILITIES COULD BE BRIEFLY LOWER.
AIRMASS WILL BECOME MORE STABLE LATE TONIGHT AND EXPECT MOSTLY VFR
WITH SCATTERED CLOUDS AFTER 07Z.
WEST SURFACE WINDS MAY PRODUCE WIND GUSTS UP TO 25 KNOTS AT TIMES
THIS AFTERNOON AND EARLY TONIGHT. OTHERWISE...WEST OR SOUTHWEST
WINDS UP TO 12 KNOTS WILL BE THE RULE LATE TONIGHT AND TUESDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF
SHORT TERM...LEE
LONG TERM....JEH
AVIATION...JEH
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1200 PM EST MON NOV 17 2014
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 331 AM EST MON NOV 17 2014
SCATTERED SNOW SHOWERS WILL DEVELOP AND CONTINUE INTO THE EVENING
AS MUCH COLDER AIR SPREADS INTO THE OHIO VALLEY. VERY COLD WEATHER
WILL CONTINUE THROUGH MIDWEEK...WITH CHANCES FOR SNOW AGAIN ON
WEDNESDAY AS A WEAK UPPER LEVEL WAVE PASSES THROUGH THE REGION.
LOW PRESSURE TRACKING INTO THE REGION OVER THE WEEKEND WILL BRING
A RETURN TO UNSETTLED WEATHER ALONG WITH WARMER TEMPERATURES.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1121 AM EST MON NOV 17 2014
THE REMAINING COUNTIES IN THE WINTER WEATHER ADVISORY WERE
CANCELLED AS THE SNOW HAS SINCE EXITED THE REGION.
DRIER AIR IS WRAPPING BACK INTO THE REGION AND HAS EVEN BROUGHT A
FEW PEAKS OF SUNSHINE WHICH SHOULD CONTINUE THROUGH MIDDAY. THE COLD
POOL WILL BEGIN TO SETTLE OVER THE REGION DURING THE AFTERNOON AS THE
UPPER LOW PINWHEELS INTO THE NORTHERN GREAT LAKES. THE POTENTIAL FOR
SCATTERED SHOWERS AND FLURRIES TO DEVELOP...WHICH HAS BEEN DISCUSSED
THE PAST FEW DAYS...HAS ALREADY COME TO FRUITION OVER A GOOD PORTION
OF CENTRAL INDIANA. INCREASED POPS HERE TO HIGH CHANCE FOR SCATTERED
SNOW SHOWERS AND CONTINUED MENTION OF SCATTERED FLURRIES ELSEWHERE.
AGREE WITH PREVIOUS THINKING THAT MODELS IN GENERAL TEND TO
STRUGGLE IN THIS SETUP AND OFTEN UNDERDO THE SNOW POTENTIAL
BECAUSE THEY DO NOT CAPTURE THE MESOSCALE FEATURES WELL. AND
INDEED THAT APPEARS TO BE THE CASE AS ALL OF THE REGULAR SHORT
TERM GUIDANCE IS NOT PICKING UP ON THESE CURRENT SNOW SHOWERS AND
FLURRIES...NOR SHOWING ANYTHING DEVELOP LATER THIS AFTERNOON AND
EVENING. HOWEVER THE WRF AND EVEN THE HRRR ARE PICKING UP ON THIS
TREND AND SHOW THESE SCATTERED SNOW SHOWERS INCREASING BOTH IN
COVERAGE OVER THE COUNTY WARNING AREA...AND INTENSITY. THESE MODELS
ARE CLEARLY SUPPORTING SCATTERED CONVECTIVE SNOW SHOWERS AND
POSSIBLY SQUALLS LATER THIS AFTERNOON AND INTO THE EVENING WHILE THE
NAM/GFS/EURO/GEM HAVE ABSOLUTELY NO PRECIP ACROSS THE AREA. IF THE
WRF/HRRR ARE CORRECT...AND COMBINED WITH THE GUSTY WESTERLY WINDS OF
30 MPH EXPECTED...THIS COULD CAUSE SOME POTENTIALLY SIGNIFICANT
TRAVEL CONCERNS AND ESPECIALLY FOR THE EVENING COMMUTE.
AN SPS FOR THE ABOVE CONCERNS WAS ISSUED EARLIER THIS MORNING AND
JUST RECENTLY UPDATED AND RESENT. POPS WERE ALSO INCREASED ACROSS
MOST OF THE REST OF THE CWA BASED ON THE WRF/HRRR TIMING TO HIT
HARDER ON THE CHANCES FOR WIDESPREAD SCATTERED SNOW SHOWERS. THE
HWO AND WX STORY ALSO REFLECT THIS MESSAGE...QUESTION THEN IS IS
ANOTHER ADVISORY NEEDED FOR THE EVENING COMMUTE IF POTENTIALLY WHITE
OUT CONDITIONS ARE POSSIBLE? EVEN THOUGH NO TECHNICAL CRITERIA FOR
A WINTER WX ADVISORY OR HEAVY SNOW ADVISORY WILL BE MET...AS THE
SNOW FALL ACCUMULATIONS ARE EXPECTED TO BE MINIMAL IF AT ALL ANY
ACCUM...THE IMPACT COULD BE THERE AND THAT IS WHAT WILL BE LOOKED
AT AND DISCUSSED IN THE VERY NEAR TERM. AND AS MENTIONED IN THE
PREVIOUS DISCUSSION...THE EVENING COMMUTE MIGHT BE OF GREATER
CONCERN THAN THIS MORNING/S. WHILE SNOWFALL WILL BE ONLY A
DUSTING TO A FEW TENTHS OF AN INCH AT BEST...THE SNOW WILL BE
DRIER AND MUCH EASIER TO BLOW AROUND WITH THE POTENTIAL FOR
LOCALLY REDUCED VISIBILITIES IN HEAVIER SNOW SHOWERS.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 331 AM EST MON NOV 17 2014
FORECAST CHALLENGES FOCUS ON TEMPS THROUGH THE PERIOD AND SNOW
CHANCES...PRIMARILY WEDNESDAY.
AN EVEN STRONGER BLAST OF COLD AIR OF POLAR ORIGIN POISED TO
OVERSPREAD THE OHIO VALLEY AND GREAT LAKES FOR MOST OF THE SHORT
TERM. AFOREMENTIONED SCATTERED SNOW SHOWERS WILL BE ONGOING THIS
EVENING...LIKELY NOT DIMINISHING IN INTENSITY AND COVERAGE UNTIL
CLOSER TO MIDNIGHT. WILL MAINTAIN SCATTERED FLURRIES OVERNIGHT WITH
STILL PLENTY OF FORCING ALOFT AND WILL HAVE TO MONITOR AS COULD EVEN
SEE A FEW SNOW SHOWERS LINGER WELL INTO THE OVERNIGHT.
UPPER TROUGH AND COLD POOL ALOFT CENTERED OVER THE REGION EARLY
TUESDAY...GRADUALLY LIFTING OUT BY LATE TUESDAY AS THE UPPER LOW
SHIFTS EAST INTO QUEBEC. WILL MAINTAIN A MENTION OF SCATTERED
FLURRIES INTO THE AFTERNOON...ENDING FROM WEST TO EAST AS FORCING
ALOFT WEAKENS. WEAK SURFACE RIDGING WILL QUICKLY TRACK ACROSS THE
REGION TUESDAY NIGHT BRINGING A BRIEF PERIOD OF CLEARING BEFORE
CLOUDS INCREASE IN ADVANCE OF ANOTHER APPROACHING WAVE ALOFT FROM
THE NORTHWEST.
THE UPPER WAVE WILL SWING ACROSS THE LOWER GREAT LAKES WEDNESDAY
WITH LIGHT SNOW SHOWERS IMPACTING PRIMARILY THE NORTHERN HALF OF THE
FORECAST AREA. COULD SEE SOME VERY LIGHT ACCUMS NORTH OF I-70 FROM A
DUSTING UP TO CLOSE TO AN INCH IN FAR NORTHERN COUNTIES BY LATE DAY
WEDNESDAY. BUMPED UP TO CHANCE POPS IN THE NORTH WEDNESDAY. SKIES
WILL CLEAR WEDNESDAY NIGHT AS HIGH PRESSURE REESTABLISHES ALONG WITH
A RENEWED SURGE OF COLDER AIR.
TEMPS...DEFINITELY THE BIG STORY OF THE SHORT TERM. UNDERCUT MOS
GUIDANCE FOR LOWS TONIGHT WITH SNOWCOVER AND 850MB TEMPS BOTTOMING
OUT AT -21 TO -20C BY TUESDAY MORNING. THINK MOST LOCATIONS GET INTO
THE SINGLE DIGITS. ONLY MODEST RECOVERY FOR TUESDAY AS HIGHS WILL
END UP RIGHT AROUND 20. LEANED CLOSER TO COOLER END OF GUIDANCE THE
REST OF THE WAY...WITH HIGHS RECOVERING INTO THE LOWER/MID 30S FOR
WEDNESDAY.
INDY RECORDS FOR TUESDAY...RECORD LOW IS 5 (1880) AND RECORD LOW MAX
TEMP IS 20 (1880). POTENTIAL FOR THE FIRST SINGLE DIGIT LOW IN
NOVEMBER SINCE 11/30/1976.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ISSUED AT 331 AM EST MON NOV 17 2014
ENSEMBLES SUGGEST A DEEP UPPER TROUGH INITIALLY OVER THE EASTERN
PARTS OF THE COUNTRY WILL BE LIFTING OFF TO THE NORTHEAST BY LATE IN
THE WEEK...LEAVING A MORE ZONAL FLOW OVER THE LOCAL AREA.
THE NEXT SYSTEM THAT MAY AFFECT THE AREA DURING THIS PERIOD WILL BE
A DISTURBANCE OF PACIFIC ORIGIN. THERE IS STILL QUITE A BIT OF
SPREAD AMONG THE ENSEMBLES AS TO THE TIMING OF THIS FEATURE...FROM
AS EARLY AS FRIDAY NIGHT TO AS LATE AS SATURDAY NIGHT OR SUNDAY. FOR
NOW...WILL BROADBRUSH POPS STARTING FRIDAY NIGHT THROUGH NEXT
SUNDAY. THERE MAY STILL BE ENOUGH RESIDUAL COLD AIR AROUND FOR MIXED
PRECIPITATION OVER PARTS OF THE AREA FRIDAY NIGHT THROUGH SATURDAY
NIGHT...BUT ENSEMBLES SUGGEST LITTLE THREAT FOR SIGNIFICANT
ACCUMULATIONS AT THIS TIME.
&&
.AVIATION /DISCUSSION FOR THE 171800Z TAF ISSUANCE/...
ISSUED AT 1200 PM EST MON NOV 17 2014
MOSTLY MVFR CEILINGS WITH SCATTERED LIGHT SNOW SHOWERS THROUGH THIS
EVENING. THEN VFR LATE TONIGHT UNTIL MIDDAY TUESDAY.
SATELLITE AND WEATHER DEPICTION INDICATED BROKEN TO SCATTERED CLOUDS
AROUND 25 HUNDRED FEET ACROSS THE AREA. WITH STRONG COLD ADVECTION
AIRMASS WILL BECOME MORE UNSTABLE LATE THIS AFTERNOON AND EARLY
TONIGHT AS AN UPPER TROUGH MOVES INTO OUR AREA. SEVERAL HIGH
RESOLUTION MODELS HINT AT DEVELOPMENT OF SNOW SHOWERS WHICH COULD
CAUSE RAPID FLUCTUATION IN VISIBILITIES BY 20Z AND LASTING AT LEAST
THROUGH MIDNIGHT. WILL ADD A PREVAILING 4 MILES AND SNOW SHOWERS
BEGINNING 20Z...ALTHOUGH VISIBILITIES COULD BE BRIEFLY LOWER.
AIRMASS WILL BECOME MORE STABLE LATE TONIGHT AND EXPECT MOSTLY VFR
WITH SCATTERED CLOUDS AFTER 07Z.
WEST SURFACE WINDS MAY PRODUCE WIND GUSTS UP TO 25 KNOTS AT TIMES
THIS AFTERNOON AND EARLY TONIGHT. OTHERWISE...WEST OR SOUTHWEST
WINDS UP TO 12 KNOTS WILL BE THE RULE LATE TONIGHT AND TUESDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SMF/RYAN
NEAR TERM...SMF
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JH
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1148 AM EST MON NOV 17 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 331 AM EST MON NOV 17 2014
SCATTERED SNOW SHOWERS WILL DEVELOP AND CONTINUE INTO THE EVENING
AS MUCH COLDER AIR SPREADS INTO THE OHIO VALLEY. VERY COLD WEATHER
WILL CONTINUE THROUGH MIDWEEK...WITH CHANCES FOR SNOW AGAIN ON
WEDNESDAY AS A WEAK UPPER LEVEL WAVE PASSES THROUGH THE REGION.
LOW PRESSURE TRACKING INTO THE REGION OVER THE WEEKEND WILL BRING
A RETURN TO UNSETTLED WEATHER ALONG WITH WARMER TEMPERATURES.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1121 AM EST MON NOV 17 2014
THE REMAINING COUNTIES IN THE WINTER WEATHER ADVISORY WERE
CANCELLED AS THE SNOW HAS SINCE EXITED THE REGION.
DRIER AIR IS WRAPPING BACK INTO THE REGION AND HAS EVEN BROUGHT A
FEW PEAKS OF SUNSHINE WHICH SHOULD CONTINUE THROUGH MIDDAY. THE COLD
POOL WILL BEGIN TO SETTLE OVER THE REGION DURING THE AFTERNOON AS THE
UPPER LOW PINWHEELS INTO THE NORTHERN GREAT LAKES. THE POTENTIAL
FOR SCATTERED SHOWERS AND FLURRIES TO DEVELOP...WHICH HAS BEEN DISCUSSED
THE PAST FEW DAYS...HAS ALREADY COME TO FRUITION OVER A GOOD
PORTION OF CENTRAL INDIANA. INCREASED POPS HERE TO HIGH CHANCE FOR
SCATTERED SNOW SHOWERS AND CONTINUED MENTION OF SCATTERED FLURRIES
ELSEWHERE.
AGREE WITH PREVIOUS THINKING THAT MODELS IN GENERAL TEND TO
STRUGGLE IN THIS SETUP AND OFTEN UNDERDO THE SNOW POTENTIAL
BECAUSE THEY DO NOT CAPTURE THE MESOSCALE FEATURES WELL. AND
INDEED THAT APPEARS TO BE THE CASE AS ALL OF THE REGULAR SHORT
TERM GUIDANCE IS NOT PICKING UP ON THESE CURRENT SNOW
SHOWERS AND FLURRIES...NOR SHOWING ANYTHING DEVELOP LATER THIS AFTERNOON
AND EVENING. HOWEVER THE WRF AND EVEN THE HRRR ARE PICKING UP ON
THIS TREND AND SHOW THESE SCATTERED SNOW SHOWERS INCREASING BOTH
IN COVERAGE OVER THE COUNTY WARNING AREA...AND INTENSITY. THESE
MODELS ARE CLEARLY SUPPORTING SCATTERED CONVECTIVE SNOW SHOWERS
AND POSSIBLY SQUALLS LATER THIS AFTERNOON AND INTO THE EVENING
WHILE THE NAM/GFS/EURO/GEM HAVE ABSOLUTELY NO PRECIP ACROSS THE
AREA. IF THE WRF/HRRR ARE CORRECT...AND COMBINED WITH THE GUSTY
WESTERLY WINDS OF 30 MPH EXPECTED...THIS COULD CAUSE SOME
POTENTIALLY SIGNIFICANT TRAVEL CONCERNS AND ESPECIALLY FOR THE
EVENING COMMUTE.
AN SPS FOR THE ABOVE CONCERNS WAS ISSUED EARLIER THIS MORNING AND
JUST RECENTLY UPDATED AND RESENT. POPS WERE ALSO INCREASED ACROSS
MOST OF THE REST OF THE CWA BASED ON THE WRF/HRRR TIMING TO HIT
HARDER ON THE CHANCES FOR WIDESPREAD SCATTERED SNOW SHOWERS. THE
HWO AND WX STORY ALSO REFLECT THIS MESSAGE...QUESTION THEN IS IS
ANOTHER ADVISORY NEEDED FOR THE EVENING COMMUTE IF POTENTIALLY WHITE
OUT CONDITIONS ARE POSSIBLE? EVEN THOUGH NO TECHNICAL CRITERIA FOR
A WINTER WX ADVISORY OR HEAVY SNOW ADVISORY WILL BE MET...AS THE
SNOW FALL ACCUMULATIONS ARE EXPECTED TO BE MINIMAL IF AT ALL ANY
ACCUM...THE IMPACT COULD BE THERE AND THAT IS WHAT WILL BE LOOKED
AT AND DISCUSSED IN THE VERY NEAR TERM. AND AS MENTIONED IN THE
PREVIOUS DISCUSSION...THE EVENING COMMUTE MIGHT BE OF GREATER
CONCERN THAN THIS MORNING/S. WHILE SNOWFALL WILL BE ONLY A
DUSTING TO A FEW TENTHS OF AN INCH AT BEST...THE SNOW WILL BE
DRIER AND MUCH EASIER TO BLOW AROUND WITH THE POTENTIAL FOR
LOCALLY REDUCED VISIBILITIES IN HEAVIER SNOW SHOWERS.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 331 AM EST MON NOV 17 2014
FORECAST CHALLENGES FOCUS ON TEMPS THROUGH THE PERIOD AND SNOW
CHANCES...PRIMARILY WEDNESDAY.
AN EVEN STRONGER BLAST OF COLD AIR OF POLAR ORIGIN POISED TO
OVERSPREAD THE OHIO VALLEY AND GREAT LAKES FOR MOST OF THE SHORT
TERM. AFOREMENTIONED SCATTERED SNOW SHOWERS WILL BE ONGOING THIS
EVENING...LIKELY NOT DIMINISHING IN INTENSITY AND COVERAGE UNTIL
CLOSER TO MIDNIGHT. WILL MAINTAIN SCATTERED FLURRIES OVERNIGHT WITH
STILL PLENTY OF FORCING ALOFT AND WILL HAVE TO MONITOR AS COULD EVEN
SEE A FEW SNOW SHOWERS LINGER WELL INTO THE OVERNIGHT.
UPPER TROUGH AND COLD POOL ALOFT CENTERED OVER THE REGION EARLY
TUESDAY...GRADUALLY LIFTING OUT BY LATE TUESDAY AS THE UPPER LOW
SHIFTS EAST INTO QUEBEC. WILL MAINTAIN A MENTION OF SCATTERED
FLURRIES INTO THE AFTERNOON...ENDING FROM WEST TO EAST AS FORCING
ALOFT WEAKENS. WEAK SURFACE RIDGING WILL QUICKLY TRACK ACROSS THE
REGION TUESDAY NIGHT BRINGING A BRIEF PERIOD OF CLEARING BEFORE
CLOUDS INCREASE IN ADVANCE OF ANOTHER APPROACHING WAVE ALOFT FROM
THE NORTHWEST.
THE UPPER WAVE WILL SWING ACROSS THE LOWER GREAT LAKES WEDNESDAY
WITH LIGHT SNOW SHOWERS IMPACTING PRIMARILY THE NORTHERN HALF OF THE
FORECAST AREA. COULD SEE SOME VERY LIGHT ACCUMS NORTH OF I-70 FROM A
DUSTING UP TO CLOSE TO AN INCH IN FAR NORTHERN COUNTIES BY LATE DAY
WEDNESDAY. BUMPED UP TO CHANCE POPS IN THE NORTH WEDNESDAY. SKIES
WILL CLEAR WEDNESDAY NIGHT AS HIGH PRESSURE REESTABLISHES ALONG WITH
A RENEWED SURGE OF COLDER AIR.
TEMPS...DEFINITELY THE BIG STORY OF THE SHORT TERM. UNDERCUT MOS
GUIDANCE FOR LOWS TONIGHT WITH SNOWCOVER AND 850MB TEMPS BOTTOMING
OUT AT -21 TO -20C BY TUESDAY MORNING. THINK MOST LOCATIONS GET INTO
THE SINGLE DIGITS. ONLY MODEST RECOVERY FOR TUESDAY AS HIGHS WILL
END UP RIGHT AROUND 20. LEANED CLOSER TO COOLER END OF GUIDANCE THE
REST OF THE WAY...WITH HIGHS RECOVERING INTO THE LOWER/MID 30S FOR
WEDNESDAY.
INDY RECORDS FOR TUESDAY...RECORD LOW IS 5 (1880) AND RECORD LOW MAX
TEMP IS 20 (1880). POTENTIAL FOR THE FIRST SINGLE DIGIT LOW IN
NOVEMBER SINCE 11/30/1976.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ISSUED AT 331 AM EST MON NOV 17 2014
ENSEMBLES SUGGEST A DEEP UPPER TROUGH INITIALLY OVER THE EASTERN
PARTS OF THE COUNTRY WILL BE LIFTING OFF TO THE NORTHEAST BY LATE IN
THE WEEK...LEAVING A MORE ZONAL FLOW OVER THE LOCAL AREA.
THE NEXT SYSTEM THAT MAY AFFECT THE AREA DURING THIS PERIOD WILL BE
A DISTURBANCE OF PACIFIC ORIGIN. THERE IS STILL QUITE A BIT OF
SPREAD AMONG THE ENSEMBLES AS TO THE TIMING OF THIS FEATURE...FROM
AS EARLY AS FRIDAY NIGHT TO AS LATE AS SATURDAY NIGHT OR SUNDAY. FOR
NOW...WILL BROADBRUSH POPS STARTING FRIDAY NIGHT THROUGH NEXT
SUNDAY. THERE MAY STILL BE ENOUGH RESIDUAL COLD AIR AROUND FOR MIXED
PRECIPITATION OVER PARTS OF THE AREA FRIDAY NIGHT THROUGH SATURDAY
NIGHT...BUT ENSEMBLES SUGGEST LITTLE THREAT FOR SIGNIFICANT
ACCUMULATIONS AT THIS TIME.
&&
.AVIATION /DISCUSSION FOR THE 171500Z KIND TAF UPDATE/...
ISSUED AT 928 AM EST MON NOV 17 2014
MINOR TWEAKS MADE TO KIND TAF TO BETTER MATCH CURRENT CONDITIONS.
NO OTHER CHANGES ARE NEEDED AT THIS TIME.
PREVIOUS AVIATION DISCUSSION FOLLOWS...
BACK EDGE OF LOWER MVFR CEILINGS AROUND 012 CURRENTLY MOVING INTO
THE WESTERN BORDER ZONES. EXTRAPOLATION AND SHORT TERM MODELS
SUGGEST THESE LOWER CEILINGS WILL SCATTER OUT OVER THE TAF SITES BY
171400Z.
LOW LEVEL LAPSE RATES BECOME NEAR DRY ADIABATIC BY EARLY
AFTERNOON...SO EXPECTING VFR CEILINGS AROUND 040 TO DEVELOP BY THAT
TIME...AS WELL AS SCATTERED SNOW SHOWERS. MODEL GUIDANCE SUGGESTS
BRIEF IFR VISIBILITY RESTRICTIONS POSSIBLE IN THE HEAVIER
SHOWERS...BUT DUE TO THE SCATTERED NATURE OF THE SHOWERS...WILL
REFRAIN FROM AN EXPLICIT MENTION AT THIS TIME.
SURFACE WINDS EXPECTED TO GRADUALLY INCREASE AS THE MORNING GOES
BY...WITH GUSTS AROUND 25 KTS FROM 270-300 DEGREES EXPECTED BY THIS
AFTERNOON.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SMF/RYAN
NEAR TERM...SMF
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS/JH
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AREA FORECAST DISCUSSION
NWS MARQUETTE MI
501 PM EST MON NOV 17 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 500 PM EST MON NOV 17 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A HIGHLY AMPLIFIED PATTERN
OVER NAMERICA...FEATURING A STRONG RIDGE OVER THE WRN PART OF THE
CONTINENT AND A SHARP...DEEPENING DOWNSTREAM TROF OVER THE CNTRL
PART. WITH THE RIDGE...THE 500MB HEIGHT ANOMALY PEAKS AT 2.5
STANDARD DEVIATIONS ABOVE AVG FOR THIS TIME OF YEAR OVER FAR NW
CANADA WHILE THE DOWNSTREAM TROF IS DEEPENING TOWARD 3.5 STANDARD
DEVIATIONS BELOW AVG OVER THE UPPER MISSISSIPPI VALLEY BY EVENING.
AT THE SFC...LOW PRES WAS LOCATED OVER FAR NE LAKE SUPERIOR WITH SFC
TROF EXTENDING SW INTO WRN UPPER MI. UPSTREAM 12Z SOUNDINGS AT
KINL/CWPL SHOWED DEEP MOISTURE EXTENDING UP PAST 500MB WITH 850MB
TEMPS OF -19/-20C RESPECTIVELY...OBVIOUSLY A FAVORABLE SETUP FOR HVY
SNOW OFF LAKE SUPERIOR.
THE SHORT TERM FCST WILL BE DOMINATED BY LES TRENDS/SNOW AMOUNTS AND
HEADLINES.
MDT/HVY SNOW HAS CONTINUED TO EXPAND OVER WRN UPPER MI THIS AFTN AND
THAT WILL CONTINUE THIS EVENING AS WEAK DEEP LAYER FORCING/DEEP
MOISTURE AND ESSENTIALLY AN ABSENT INVERSION ALLOW FOR DEEP LAKE
EFFECT CONVECTION. ALTHOUGH DGZ IS ONLY AROUND 2KFT THICK...FCST
SOUNDINGS SHOW IT IDEALLY PLACED WITHIN MAX UPWARD MOTION. HIGHER
RES MODEL GUIDANCE CONTINUES TO SHOW BEST LOW-LEVEL CONVERGENCE
TONIGHT IN AN AREA FROM KIWD INTO CNTRL/SRN HOUGHTON COUNTY AND ALSO
DEVELOPING THIS EVENING IN ALGER/NRN SCHOOLCRAFT COUNTIES. THUS...
EXPECT HEAVIEST SNOWFALL IN THESE AREAS. WHILE THE W GETS A BETTER
BOOST FROM TERRAIN ENHANCEMENT...A NICE LAKE NIPIGON CONNECTION AND
LAND BREEZE CONVERGENCE OFF MARQUETTE COUNTY WILL BOOST SNOWFALL
INTO ALGER/NRN SCHOOLCRAFT. ISOLATED LOCATIONS IN BOTH AREAS MAY SEE
TOTAL SNOW ACCUMULATIONS AROUND 20 INCHES BY THE TIME THE SNOW
DIMINISHES/ENDS. OTHERWISE...12-18 INCHES OF SNOW WILL GENERALLY BE
THE RULE. A LITTLE CONCERNED ABOUT HOW FAR THE HEAVIER SNOW MAY
EXTEND INTO SRN SCHOOLCRAFT TONIGHT. IF DOMINANT BAND SETS UP AND
DOESN`T MOVE MUCH FOR SEVERAL HRS...AMOUNTS MAY SNEAK INTO WARNING
CRITERIA THERE. OVER NRN HOUGHTON/KEWEENAW COUNTIES...MANY LOCATIONS
WILL PROBABLY END UP WITH SUB WARNING AMOUNTS GIVEN LACK OF
ENHANCING FACTORS THAT ARE PRESENT IN THE OTHER AFORMENTIONED
AREAS. BEST POTENTIAL OF EXCEEDING A FOOT WILL BE SOUTH OF
PAINESDALE AND PERHAPS NRN KEWEENAW COUNTY AS LAKE NIPIGON
CONNECTION MAY IMPACT THAT AREA FOR A TIME THIS EVENING. BLSN WILL
BE MORE SIGNIFICANT ACROSS THE KEWEENAW...SO THAT WILL BE A FACTOR
SUPPORTING MAINTAINING WARNING HEADLINES FOR NOW. CONSIDERED
DROPPING ADVY FOR MARQUETTE COUNTY AS WINDS HAVE A BIT TOO MUCH OF A
WESTERLY COMPONENT TO BRING MUCH OF THE HEAVIER SNOW INTO THE
COUNTY. HAVE LOWERED SNOW ACCUMULATIONS...BUT SOME HIGH RES GUIDANCE
CONTINUES TO SHOW HEAVIER SNOW BANDS BRUSHING THE SHORELINE AREAS.
IN PARTICULAR...THE AREA TOWARD SHOT POINT MAY BE AFFECTED BY HVY
SNOW AT TIMES. WRN PART OF THE COUNTY MAY SEE FAIRLY PERSISTENT SNOW
FOR THE NEXT SEVERAL HRS AS WELL BEFORE WINDS VEER A LITTLE MORE NW.
FOR NOW...MAINTAINED MARQUETTE COUNTY ADVY...BUT EVENING SHIFT MAY
BE ABLE TO DROP ADVY IF IT DOES APPEAR HEAVIER SNOW WILL REMAIN E.
ON TUE...DEEP MOISTURE SLOWLY SHIFTS E...LARGER SCALE LOW-LEVEL FLOW
TRENDS ANTICYCLONIC AND OVERALL LOW-LEVEL CONVERGENCE WEAKENS. THIS
WILL SPELL DIMINISHING LES FROM W TO E DURING THE DAY. BACKING WINDS
WILL PUSH LINGERING -SHSN N OF KIWD DURING THE AFTN AND SHIFT THE
BACK EDGE OF LES EASTWARD WITH TIME IN CNTRL UPPER MI. THOSE BACKING
WINDS WILL ALSO LEAD TO A NARROW ENHANCED CONVERGENCE ZONE SHIFTING
N OVER FAR WRN UPPER MI LATER IN THE AFTN...RESULTING IN A NARROW
BAND OF HEAVIER SNOW SHIFTING N TOWARD HOUGHTON IN THE EVENING.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 444 PM EST MON NOV 17 2014
BY 00Z WEDNESDAY THE 500MB LOW WILL HAVE SHIFTED FROM FAR E ONTARIO
TO E QUEBEC...WITH RIDGING AT THE SFC AND ALOFT. THIS WILL ALLOW THE
NEAR SFC WINDS TO SHIFT A BIT MORE OUT OF THE W AND SW
OVERNIGHT...ALLOWING LES TO PUSH OFFSHORE AND INTO LAKE SUPERIOR.
THIS DRY WX WILL BE TEMPORARILY...AS THE NEXT SFC TROUGH AND 500MB
SHORTWAVE LOOK TO BE SET UP ACROSS MN ALREADY AT 06Z WEDNESDAY.
THERE ISN/T A LOT OF MOISTURE TO WORK WITH INITIALLY. HOWEVER...THE
SFC THROUGH WILL SLIDE ACROSS W AND CENTRAL UPPER MI BY 18Z
WEDNESDAY...WITH STRONGER DYNAMICS MOVING IN LATER WEDNESDAY
AFTERNOON. NW WINDS BEHIND THIS TROUGH DOES NOT LOOK TOO STRONG
WEDNESDAY NIGHT INTO THURSDAY /AT LEAST COMPARED TO THE NEARLY 40KTS
OF THIS CURRENT SYSTEM/. WINDS ARE MORE ON THE ORDER OF 30KTS ABOVE
900MB. A 500MB LOW ROTATING IN WEDNESDAY NIGHT WILL USHER IN MUCH
COOLER AIR...WITH 850MB TEMPS FALLING FROM AN AVERAGE -14C WEDNESDAY
AFTERNOON TO AROUND -19C BY THURSDAY AFTERNOON. THE GFS IS A COUPLE
DEGREES WARMER ALOFT THAN THE ECMWF VALUES LISTED ABOVE. THIS SHOULD
HAVE LITTLE IMPACT ON THE OVERALL TRENDS. CONTINUE TO HIGHLIGHT THE
POTENTIAL FOR MODERATE TO HEAVY LAKE EFFECT SNOW SHOWERS LATE
WEDNESDAY AFTERNOON/WEDNESDAY NIGHT THROUGH THURSDAY NIGHT. LOOK FOR
A CHANGE IN THE PERSISTENT COOL NW FLOW THURSDAY NIGHT...WITH
CLEARING CONDITIONS OVER THE INTERIOR W HALF. THIS SHOULD ALLOW SFC
TEMPS TO FALL TO AROUND 0F. THE DEEPENING/EXITING SFC LOW OVER S
QUEBEC THURSDAY WILL KEEP A TROUGH ACROSS THE UPPER GREAT LAKES INTO
THURSDAY EVENING...AS LARGE 500MB TROUGH FINALLY EXITS INTO E
CANADA. LOOK FOR LES TO SLOWLY END ONCE AGAIN AS WINDS BECOME A BIT
MORE VARIANT...SHIFTING OUT OF THE W. HIGH PRESSURE WILL THEN RETURN
TO THE AREA...WITH DRY WEATHER FOR MUCH OF FRIDAY INTO SATURDAY.
FRIDAY NIGHT INTO SATURDAY IS A BIT OF A CONUNDRUM...WITH STRONG WAA
ON 850MB WINDS OF 40-50KTS FCST OFF BOTH THE 12Z GFS AND ECMWF.
WHILE WINTER IS FAR FROM OVER...WE MAY GET A BIT OF A BREAK FROM THE
WHITE STUFF. MAY HAVE WAA SHOWERS SATURDAY AFTERNOON IN ADVANCE OF
THE SFC TROUGH AND ASSOCIATED SHORTWAVE ACROSS NW MN. AT THIS POINT
THE BEST CHANCE FOR A MIX OF RAIN AND SNOW WILL BE ACROSS LAKE MI.
WILL NOT GET TOO INTO THE DETAILS FOR SUNDAY AND MONDAY...OTHER THAN
TO NOTE THAT MUCH WARMER AIR LOOKS TO PUSH IN FOR SUNDAY. HIGHS
COULD TOP OUT IN THE MID TO UPPER 30S...AS S-SSE WINDS CONTINUE IN
ADVANCE OF LOW PRESSURE EJECTING OUT OF THE S PLAINS. THE 12Z ECMWF
TRACKS A VERY STRONG/WRAPPED UP 927MB SFC LOW ACROSS WI AND UPPER MI
SUNDAY NIGHT INTO MONDAY. WHILE THE GFS IS SHOWING A SIMILAR
FEATURE...ITS/S TRACK IS ACROSS LOWER MI STARTING OFF AT 989MB AND
WEAKENING OVER THIS TIME PERIOD. WILL KEEP A GENERAL BLEND GOING FOR
FRIDAY NIGHT AND BEYOND. WOULD NOT BE SURPRISED IF WE NEED TO
INCREASE OUR CURRENT WIND FCST FOR THIS PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1216 PM EST MON NOV 17 2014
DEEP MID/UPPER LEVEL TROF AND ASSOCIATED DEEP MOISTURE PUSHING
ACROSS THE AREA WILL LEAD TO HEAVIER LAKE EFFECT SNOW SHOWERS
AFFECTING KIWD/KCMX UNDER NW FLOW. COMBINATION OF SNOW AND GUSTY NW
WINDS CREATING BLSN WILL LIKELY RESULT IN LIFR CONDITIONS PREVAILING
AT BOTH TERMINALS. AS DEEPER MOISTURE BEGINS TO EXIT...EXPECT
IMPROVEMENT TO IFR LATE TONIGHT/EARLY TUE MORNING AND THEN TO MVFR
BY TUE AFTN. AT KSAW...NW WIND DIRECTION WILL NOT BE FAVORABLE FOR
ANYTHING MORE THAN -SHSN AT TIMES. MVFR CIGS WILL DEVELOP THIS AFTN
AND CONTINUE THRU THE REMAINDER OF THE FCST PERIOD. THERE MAY BE A
FEW PERIODS OF MVFR VIS IN -SHSN LATER THIS AFTN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 500 PM EST MON NOV 17 2014
LOW PRESSURE OVER FAR NE LAKE SUPERIOR WILL SHIFT EAST THIS EVENING
WITH TRAILING SFC TROF SWEEPING SE. BEHIND THE TROF...EXPECT NW
GALES OF 35-40KT TO SRPEAD FROM WRN LAKE SUPERIOR TO ERN LAKE
SUPERIOR. COULD BE SOME GUSTS TO NEAR 45KT OVER SCNTRL LAKE SUPERIOR
FOR A TIME TONIGHT. GALES WILL END OVER THE W OVERNIGHT AND OVER THE
E LATE TUE MORNING/EARLY AFTN. COLD AIR/STRONG WINDS/HIGH WAVES WILL
ALSO LEAD TO SOME FREEZING SPRAY. WINDS SHOULD GENERALLY BE IN THE
15-25KT RANGE TUE NIGHT AS WINDS BACK SW AHEAD OF THE NEXT TROF.
THAT TROF WILL SWEEP ACROSS THE LAKE WED AFTN/EVENING...FOLLOWED BY
ANOTHER ROUND OF NW WINDS TO AT LEAST 30KT. GALES MAY OCCUR OVER THE
E HALF OF THE LAKE WED NIGHT/THU MORNING. NO ADDITIONAL GALES ARE
EXPECTED THRU SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST /NOON CST/ TUESDAY FOR
MIZ001>003-009-084.
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST TUESDAY FOR MIZ006-085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST TUESDAY FOR MIZ007.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST TUESDAY FOR MIZ004-005.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST TUESDAY FOR MIZ014.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TO 1 PM EST TUESDAY FOR LSZ251-267.
GALE WARNING UNTIL 1 PM EST TUESDAY FOR LSZ248>250-265-266.
GALE WARNING UNTIL 9 AM EST TUESDAY FOR LSZ264.
GALE WARNING UNTIL 4 AM EST /3 AM CST/ TUESDAY FOR LSZ240>242-
263.
GALE WARNING UNTIL 7 AM EST TUESDAY FOR LSZ243>245.
GALE WARNING UNTIL 1 AM EST /MIDNIGHT CST/ TUESDAY FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
452 PM EST MON NOV 17 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 411 AM EST MON NOV 17 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS INDICATE A DEEPENING
UPR TROF OVER CENTRAL NAMERICA WITH CLOSED H5 LO OVER ONTARIO JUST
NW OF LK SUP CAUSING 12HR H5 HGT FALLS UP TO 130M BTWN 16/12Z AND
17/00Z AT INL AND DRAWING H5 TEMPS CLOSE TO -40C S UNDER THE AXIS OF
LOWEST HGTS. BAND OF DPVA/DEEP LYR QVECTOR CNVGC/AXIS OF MID LVL
MSTR IN ADVANCE OF SHRTWV ROTATING ARND THE CLOSED LO IS CROSSING
UPR MI EARLY THIS MRNG...BUT DRYNESS OF AIRMASS SHOWN ON THE 00Z GRB
RAOB /PWAT 0.16 INCH IS 45 PCT OF NORMAL/ IS GREATLY LIMITING THE
COVERAGE/INTENSITY OF ACCOMPANYING LIGHT SN. THERE HAS BEEN SOME
LIGHT SN OVER THE FAR E NEAR NEWBERRY WITH A SW WIND OFF NRN LK
MI...BUT THE FLOW HAS NOT BACKED SUFFICIENTLY TO CAUSE THE HEAVIER
SN SHOWERS IN MACKINAC COUNTY TO IMPACT LUCE/SCHOOLCRAFT COUNTIES.
LOOKING TO THE W...THE 00Z H85/7 TEMPS WERE -17C/-27C AT INL /VS
-14C AND -16C AT GRB/. THE 00Z INL IS QUITE MOIST ALMOST UP TO H5
WITHIN A DEEP CYC FLOW. THERE IS A SHARP SFC WSHFT FM W TO NW ALONG
A SFC LO PRES TROF RUNNING THRU NRN MN INTO ADJACENT ONTARIO...WITH
SFC REPORTS SHOWING SOME MODERATE SN ALONG AND JUST BEHIND THIS
BNDRY.
MAIN FOCUS IN THE SHORT TERM WL BE ON LES AMOUNTS/GOING HEADLINES
ASSOCIATED WITH INCOMING COLD/MOIST AIRMASS. MADE NO CHANGES ATTM TO
HEADLINES ISSUED BY THE PREVIOUS SHIFT.
TODAY...AS CUTOFF H5 LO DEEPENS FURTHER AND SLIDES SLOWLY TO THE E
ACROSS UPR MI...SHARP CYC LLVL FLOW IS FCST TO SLOWLY ENVELOP THE
CWA W-E WITH A WSHFT FM WSW EARLY THIS MRNG TO NW BY LATE IN THE DAY
EXCEPT OVER THE SE CWA. THE SHARPER LLVL CNVGC WL ARRIVE OVER THE W
ARND 12Z AND RESULT IN INCRSG SN RATES DESPITE SOME DEEP LYR QVECTOR
DVGC IN THE WAKE OF THE SHRTWV ROTATING THRU THE UPR LKS EARLY THIS
MRNG. THE HIER RES MODELS HAVE CONSISTENTLY POINTED TO THE AREA ARND
ONTONAGON COUNTY AS THE FOCUS FOR THE SHARPEST CNVGC. GOING START
TIME OF 12Z FOR THE WARNINGS OVER THE W APPEARS TO BE ON TRACK.
SINCE THE RATHER LO UVV MAX IN THE ABSENCE OF DEEP LYR FORCING WL BE
CENTERED IN THE DGZ...EXPECT GOOD SN/WATER RATIOS IN EXCESS OF 20:1
DESPITE A DGZ DEPTH OF ONLY ABOUT 3K FT AND INCRSG WINDS THAT WOULD
TEND TO FRAGMENT THE SN FLAKES. WITH SOME INCRSG DEEP LYR QVECTOR
CNVGC/UVV OVER THE W HALF LATER IN THE DAY UNDER THE DEEPENING UPR
TROF AXIS...FCST SDNGS ALSO INDICATE INCRSG DEEP MSTR THRU THE DAY
PER THE 00Z INL RAOB WITH EQUILIBRIUM LVLS APRCHG 10K FT OVER THE BY
LATER IN THE DAY AS H85/7 TEMPS DIP TO -16C TO -17C/-27C. INCRSG NW
WINDS/DESTABILIZATION WL RESULT IN GUSTY SFC WINDS AND SOME BLSN AS
WELL. FARTHER TO THE E...THE LLVL FLOW IS FCST TO BE OUT OF THE W
MOST OF THE DAY...SO THE SN SHOWERS THERE SHOULD BE MAINLY CONFINED
TO THE LK SHORE UNTIL AT LEAST 21Z...WHEN THE FASTER HI RES CNDN
MODEL SHOWS THE ARRIVAL OF SHARPER CYC FLOW/ WSHFT TO THE NW. FCST
LES WARNINGS FOR ALGER/NRN SCHOOLCRAFT COUNTIES BEGINS AT 21Z...SO
WL NOT CHANGE THIS START TIME. THERE SHOULD BE NOTHING MORE THAN
FLURRIES/LIGHT SN SHOWERS OVER THE SCENTRAL WITH DOWNSLOPE FLOW.
TNGT...UPR TROF/AXIS OF DEEP LYR QVECTOR CNVGC AND MSTR/SFC LO PRES
TROF AND CYC WSHFT TO THE NW ARE PROGGED TO DRIFT SLOWLY E. THESE
TRENDS WL RESULT IN INCRSG POPS/SN RATES IN THE NW SN BELTS MAINLY E
OF MARQUETTE. THE 00Z NAM AND ESPECIALLY THE HI RES CNDN MODEL HINT
LK NIPIGON MOISTENING WL GREATLY ENHANCE SN RATES OVER ALGER/NRN
SCHOOLCRAFT COUNTIES...SO THE GOING WRNGS APPEAR ON TRACK. AS WL BE
THE CASE TODAY OVER THE W...HI EQUILIBRIUM LVL AND FAVORABLE UVV MAX
WITHIN THE DGZ WL BE ENHANCING FACTORS FOR SN RATES IN THIS AREA.
ALTHOUGH THE DEPARTURE OF THE DYANAMIC SUPPORT/VERY DEEP MSTR MAY
SLOW DOWN THE HEAVY SN RATES OVER THE W BY THE OVERNGT HRS...
LINGERING CYC NW BACKING TOWARD THE WNW OVER THE FAR W TOWARD 12Z WL
CONTINUE WIDESPREAD SN SHOWERS/CATEGORICAL POPS IN THE FAVORED SN
BELTS THERE. ALTHOUGH THE EXPECTED NW FLOW IS NOT FAVORABLE FOR
MARQUETTE COUNTY...WL CONTINUE THE ADVY FOR THIS AREA GIVEN
POTENTIAL FOR HIER WINDS NEAR THE LK SHORE AND HEAVIER SN IN THE
EASTERN PART OF THE COUNTY. ONCE AGAIN...THE LIGHTEST AND LEAST
WIDESPREAD SN SHOWERS WL BE OVER THE SCENTRAL.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 444 PM EST MON NOV 17 2014
BY 00Z WEDNESDAY THE 500MB LOW WILL HAVE SHIFTED FROM FAR E ONTARIO
TO E QUEBEC...WITH RIDGING AT THE SFC AND ALOFT. THIS WILL ALLOW THE
NEAR SFC WINDS TO SHIFT A BIT MORE OUT OF THE W AND SW
OVERNIGHT...ALLOWING LES TO PUSH OFFSHORE AND INTO LAKE SUPERIOR.
THIS DRY WX WILL BE TEMPORARILY...AS THE NEXT SFC TROUGH AND 500MB
SHORTWAVE LOOK TO BE SET UP ACROSS MN ALREADY AT 06Z WEDNESDAY.
THERE ISN/T A LOT OF MOISTURE TO WORK WITH INITIALLY. HOWEVER...THE
SFC THROUGH WILL SLIDE ACROSS W AND CENTRAL UPPER MI BY 18Z
WEDNESDAY...WITH STRONGER DYNAMICS MOVING IN LATER WEDNESDAY
AFTERNOON. NW WINDS BEHIND THIS TROUGH DOES NOT LOOK TOO STRONG
WEDNESDAY NIGHT INTO THURSDAY /AT LEAST COMPARED TO THE NEARLY 40KTS
OF THIS CURRENT SYSTEM/. WINDS ARE MORE ON THE ORDER OF 30KTS ABOVE
900MB. A 500MB LOW ROTATING IN WEDNESDAY NIGHT WILL USHER IN MUCH
COOLER AIR...WITH 850MB TEMPS FALLING FROM AN AVERAGE -14C WEDNESDAY
AFTERNOON TO AROUND -19C BY THURSDAY AFTERNOON. THE GFS IS A COUPLE
DEGREES WARMER ALOFT THAN THE ECMWF VALUES LISTED ABOVE. THIS SHOULD
HAVE LITTLE IMPACT ON THE OVERALL TRENDS. CONTINUE TO HIGHLIGHT THE
POTENTIAL FOR MODERATE TO HEAVY LAKE EFFECT SNOW SHOWERS LATE
WEDNESDAY AFTERNOON/WEDNESDAY NIGHT THROUGH THURSDAY NIGHT. LOOK FOR
A CHANGE IN THE PERSISTENT COOL NW FLOW THURSDAY NIGHT...WITH
CLEARING CONDITIONS OVER THE INTERIOR W HALF. THIS SHOULD ALLOW SFC
TEMPS TO FALL TO AROUND 0F. THE DEEPENING/EXITING SFC LOW OVER S
QUEBEC THURSDAY WILL KEEP A TROUGH ACROSS THE UPPER GREAT LAKES INTO
THURSDAY EVENING...AS LARGE 500MB TROUGH FINALLY EXITS INTO E
CANADA. LOOK FOR LES TO SLOWLY END ONCE AGAIN AS WINDS BECOME A BIT
MORE VARIANT...SHIFTING OUT OF THE W. HIGH PRESSURE WILL THEN RETURN
TO THE AREA...WITH DRY WEATHER FOR MUCH OF FRIDAY INTO SATURDAY.
FRIDAY NIGHT INTO SATURDAY IS A BIT OF A CONUNDRUM...WITH STRONG WAA
ON 850MB WINDS OF 40-50KTS FCST OFF BOTH THE 12Z GFS AND ECMWF.
WHILE WINTER IS FAR FROM OVER...WE MAY GET A BIT OF A BREAK FROM THE
WHITE STUFF. MAY HAVE WAA SHOWERS SATURDAY AFTERNOON IN ADVANCE OF
THE SFC TROUGH AND ASSOCIATED SHORTWAVE ACROSS NW MN. AT THIS POINT
THE BEST CHANCE FOR A MIX OF RAIN AND SNOW WILL BE ACROSS LAKE MI.
WILL NOT GET TOO INTO THE DETAILS FOR SUNDAY AND MONDAY...OTHER THAN
TO NOTE THAT MUCH WARMER AIR LOOKS TO PUSH IN FOR SUNDAY. HIGHS
COULD TOP OUT IN THE MID TO UPPER 30S...AS S-SSE WINDS CONTINUE IN
ADVANCE OF LOW PRESSURE EJECTING OUT OF THE S PLAINS. THE 12Z ECMWF
TRACKS A VERY STRONG/WRAPPED UP 927MB SFC LOW ACROSS WI AND UPPER MI
SUNDAY NIGHT INTO MONDAY. WHILE THE GFS IS SHOWING A SIMILAR
FEATURE...ITS/S TRACK IS ACROSS LOWER MI STARTING OFF AT 989MB AND
WEAKENING OVER THIS TIME PERIOD. WILL KEEP A GENERAL BLEND GOING FOR
FRIDAY NIGHT AND BEYOND. WOULD NOT BE SURPRISED IF WE NEED TO
INCREASE OUR CURRENT WIND FCST FOR THIS PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1216 PM EST MON NOV 17 2014
DEEP MID/UPPER LEVEL TROF AND ASSOCIATED DEEP MOISTURE PUSHING
ACROSS THE AREA WILL LEAD TO HEAVIER LAKE EFFECT SNOW SHOWERS
AFFECTING KIWD/KCMX UNDER NW FLOW. COMBINATION OF SNOW AND GUSTY NW
WINDS CREATING BLSN WILL LIKELY RESULT IN LIFR CONDITIONS PREVAILING
AT BOTH TERMINALS. AS DEEPER MOISTURE BEGINS TO EXIT...EXPECT
IMPROVEMENT TO IFR LATE TONIGHT/EARLY TUE MORNING AND THEN TO MVFR
BY TUE AFTN. AT KSAW...NW WIND DIRECTION WILL NOT BE FAVORABLE FOR
ANYTHING MORE THAN -SHSN AT TIMES. MVFR CIGS WILL DEVELOP THIS AFTN
AND CONTINUE THRU THE REMAINDER OF THE FCST PERIOD. THERE MAY BE A
FEW PERIODS OF MVFR VIS IN -SHSN LATER THIS AFTN.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 646 AM EST MON NOV 17 2014
LOW PRESSURE OVER FAR NORTHERN LAKE SUPERIOR WILL SHIFT EAST
TODAY...SWEEPING A SURFACE TROUGH SOUTHEAST ACROSS LAKE SUPERIOR
TODAY. BEHIND THE TROUGH...LOOK FOR GUSTS TO INCREASE TO GALES OF
35-40KTS OVER PORTIONS OF W LAKE SUPERIOR THIS AFTERNOON...BEFORE
EXPANDING TO THE E HALF OF LAKE SUPERIOR THIS EVENING THROUGH
EARLY TUESDAY. THE TIMING OF THE GALE WARNING WAS IN GOOD SHAPE
AND WILL CONTINUE. A TROUGH WILL THEN LINGER ACROSS LAKE SUPERIOR
THROUGH TUESDAY MORNING...BEFORE BRIEFLY BEING REPLACED BY A RIDGE
TUESDAY AFTERNOON AND EVENING. ANOTHER TROUGH OVER N MANITOBA ON
TUESDAY WILL SLIDE ACROSS THE UPPER GREAT LAKES LATE TUESDAY NIGHT
THROUGH WEDNESDAY...BEFORE EXITING ACROSS THE ONTARIO AND QUEBEC
BORDER THURSDAY MORNING. A FEW NORTHWEST GALE FORCE GUSTS TO 35
KNOTS ARE POSSIBLE OVER EASTERN LAKE SUPERIOR LATE WEDNESDAY
NIGHT INTO THURSDAY MORNING. HIGH PRESSURE OVER THE N PLAINS ON
THURSDAY WILL DIVE ACROSS THE OHIO VALLEY LATE FRIDAY...EXTENDING A
RIDGE OVER THE UPPER GREAT LAKES ON FRIDAY AND DIMINISHING WINDS
BELOW 25 KNOTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST /NOON CST/ TUESDAY FOR
MIZ001>003-009-084.
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST TUESDAY FOR MIZ006-085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST TUESDAY FOR MIZ007.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST TUESDAY FOR MIZ004-005.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST TUESDAY FOR MIZ014.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TO 1 PM EST TUESDAY FOR LSZ251-267.
GALE WARNING UNTIL 1 PM EST TUESDAY FOR LSZ248>250-265-266.
GALE WARNING UNTIL 9 AM EST TUESDAY FOR LSZ264.
GALE WARNING UNTIL 4 AM EST /3 AM CST/ TUESDAY FOR LSZ240>242-
263.
GALE WARNING UNTIL 7 AM EST TUESDAY FOR LSZ243>245.
GALE WARNING UNTIL 1 AM EST /MIDNIGHT CST/ TUESDAY FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GAYLORD MI
135 PM EST MON NOV 17 2014
.SYNOPSIS...
ISSUED AT 331 AM EST MON NOV 17 2014
LOW PRESSURE PASSING TO OUR NORTH TODAY...WILL USHER IN ANOTHER
SURGE OF COLD AIR. LAKE EFFECT SNOW SHOWERS WILL CONTINUE IN SOME
PLACES TODAY...BUT HEAVY SNOW IS EXPECTED TONIGHT AND TUESDAY IN
SOME OF THE CLASSIC SNOWBELTS. ANOTHER SYSTEM WILL BRING LIGHT SNOW
TO THE REGION WEDNESDAY...AND MORE LAKE EFFECT SNOW WILL FOLLOW
BEHIND IT. HOWEVER...TEMPERATURES WILL BECOME MILDER DURING THE
UPCOMING WEEKEND.
&&
.UPDATE...
ISSUED AT 112 PM EST MON NOV 17 2014
THINGS SEEM TO BE ON TRACK FOR THE FORECAST WITH THE BANDS
REALIGNING IN SOME KIND OF W OR WNW BAND BASED ON THE KAPX RADAR
AND VIS SATELLITE IMAGE. IN E UPPER A DOMINATE W BAND HAS FORMED
IS JUST OFF THE SHORE AT WHITEFISH POINT. SO WILL MAKE SOME MINOR
TWEAKS TO WEATHER AND SNOW AMOUNTS, BUT LITTLE WILL CHANGE FOR THE
NEXT COUPLE OF HOURS.
UPDATE ISSUED AT 1013 AM EST MON NOV 17 2014
THE FRONT IS MAKING ITS WAY FROM N LAKE MICHIGAN TO NW LOWER. THIS
HAS LEAD TO THE SW SNOW BANDS MERGING AND FLARING UP AS THEY MOVE
INLAND. THIS WILL LEAD TO TO BRIEFLY HEAVY SNOW AS THE BANDS
TRANSIT THE REGION OVER THE NEXT COUPLE OF HOURS. WILL EXPECT THAT
THE BANDS WILL LOSE THEIR INTENSITY AS THEY MOVE EAST AWAY FROM
THE LAKE.
BEHIND THE FRONT, THE SNOW BANDS ARE ALREADY REFORMING WITH THE
WEST WIND OVER THE N LAKE MICHIGAN. WILL BE EXPECTING THAT THE
SNOW BANDS WILL REESTABLISH QUICKLY, BUT THE WHETHER THEY WILL
REMAIN STATIONARY OR BE TRANSIENT OVER THE AFTERNOON IS UNCERTAIN
AS THE MODELS HAVE VARYING SOLUTIONS WITH A SPREAD OF ABOUT 30
DEGREES IN THE 1000-850 MB WIND DIRECTIONS. WILL CONTINUE THE
GOING AFTERNOON FORECAST UNTIL THE BANDS SHOW THEIR INTENTIONS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 331 AM EST MON NOV 17 2014
...SIGNIFICANT LAKE EFFECT SNOW EVENT EXPECTED LATER TODAY THROUGH
TUESDAY...
HIGH IMPACT WEATHER POTENTIAL: LOCALIZED VERY HEAVY LAKE EFFECT
SNOW. AREAS OF BLOWING SNOW AND NEAR WHITEOUT CONDITIONS POSSIBLE
TONIGHT.
PATTERN SYNOPSIS/CURRENT CONDITIONS: KINDA STATING THE OBVIOUS...BUT
MID-WINTER LIKE PATTERN WELL ESTABLISHED ACROSS THE NORTHERN LAKES.
REASON FOR SUCH IS ONE ANOMALOUSLY DEEP MERIDIONAL FLOW
REGIME...CONSISTING OF FULL LENGTH WESTERN NOAM RIDGING AND JUST AS
IMPRESSIVE TROUGHING EXTENDING THROUGH THE CENTRAL PLAINS INTO THE
WESTERN LAKES. MOST IMPRESSIVE COLD SURGE YET TIED TO WAVE OF ARCTIC
ORIGIN DIVING INTO SOUTHWEST ONTARIO AND INTO MINNESOTA (-20C H8
TEMPERATURES PER LATEST RAP ANALYSIS!). SURFACE COLD FRONT RUNNING
WELL AHEAD OF THIS WAVE...ALREADY PUSHING INTO NORTHWEST MICHIGAN AT
THIS EARLY HOUR. AREA OUT AHEAD OF THIS FRONT PLENTY COLD ENOUGH TO
CONTINUE TO ENTICE A SIGNIFICANT LAKE RESPONSE (A PRETTY RARE FEAT
TO HAVE SUCH COLD PRE-FRONTAL AIR DURING MID NOVEMBER). MAIN SHOW
TONIGHT HAS BEEN DIRECTED INTO PARTS OF EASTERN UPPER MICHIGAN..
WHERE NO DOUBT SEVERAL INCHES OF ACCUMULATION HAVE ALREADY OCCURRED.
SOMEWHAT LIGHTER MORE NUISANCE TYPE SNOWS IMPACTING NORTHER
LOWER...ALTHOUGH SOME EMBEDDED HEAVIER LAKE ENHANCED SNOWS WERE
NOTED...ESPECIALLY ACROSS PARTS OF EMMET COUNTY. SIMPLY NO END IN
SIGHT...WITH CURRENT UPSTREAM WAVE SET TO AMPLIFY OVERHEAD LATER
TODAY AND TONIGHT...FORCING A SHIFTING OF THE WINDS TO MORE W/NW AND
PUTTING THE MORE TRADITIONAL LAKE EFFECT AREAS UNDER THE GUN FOR A
HIGH IMPACT WINTER WEATHER EVENT.
PRIMARY FORECAST CONCERNS/CHALLENGES: MULTIPLE! INITIAL FOCUS ON
ONGOING SW FLOW LAKE EFFECT AND ASSOCIATED HEADLINES THIS MORNING.
OVERNIGHT FOCUS ON MUCH MORE WIDESPREAD LAKE SNOW EVENT...INCLUDING
AMOUNTS AND HEADLINE MANAGEMENT CONCERNS.
DETAILS: NOT PRETTY! FIRST OFF...ONGOING SW FLOW LAKE SNOWS SHOULD
STEADILY DECLINE IN INTENSITY SHORTLY AFTER 09Z AS WINDS BEGIN TO
SLOWLY VEER AND BRIEF CORRIDOR OF UPSTREAM DRIER AIR OVERSPEADS THE
LAKES. CURRENT HEADLINES RUN THROUGH 15Z...WHICH OFFERS SOME
FLEXIBILITY IF BANDS SHOULD PERSIST LONGER THAN ANTICIPATED (NEVER
SEEN THAN BEFORE :)). NO OFFICIAL REPORTS JUST YET...BUT BASED OFF
MACKINAC BRIDGE WEB CAMS AND SOME INFORMATION GLEANED FROM CALLING
ST. IGNACE...GOTTA FEELING WE WILL BE DEALING WITH SOME IMPRESSIVE
SNOWFALL TOTALS UP IN THE STRAITS AREA BEFORE ALL IS SAID AND DONE
THIS MORNING. ELSEWHERE...JUST SOME LIGHTER SNOWS EXPECTED AS THE
COLD FRONT PUSHES EAST...EXITING STAGE RIGHT BY MID-MORNING.
WITH PART ONE DONE...ALL FOCUS SHIFTS TO WHAT INCREASINGLY LOOKS
LIKE A VERY SIGNIFICANT AND PROLONGED LAKE EFFECT EVENT FOR THE MORE
TRADITIONAL SNOW BELTS OF EASTERN UPPER AND NORTHERN LOWER MICHIGAN.
CURRENT SOUTHWEST ONTARIO WAVE CONTINUES TO DIG...SLOWLY CROSSING
THE NORTHERN LAKES THROUGH THE OVERNIGHT. DESPITE MAIN CORE OF
ATTENDANT CAA ACTUALLY PASSING US BY TO THE SOUTH...INSTABILITY
RAMPS UP IMPRESSIVELY LATE TODAY THROUGH THE OVERNIGHT...WITH NEAR
EXTREME DELTA T/S COLLOCATED WITH DEEP SYNOPTIC MOISTURE SUPPORT AND
ESSENTIALLY ALL LOSS OF AN INVERSION. CYCLONIC FLOW IS IMPRESSIVE...
SUGGESTING ENHANCED CONVERGENCE TARGETING NORTHWEST LOWER MICHIGAN.
LOW LEVEL FLOW IS SLIGHTLY MORE BACKED IN RECENT GUIDANCE
RUNS...WELL SUPPORTED BY WHAT SHOULD BE STRENGTHENING LAKE DRIVEN
SURFACE TROUGH DEVELOPMENT. AFTER A BRIEF BREAK THIS AFTERNOON...
EXPECT SNOWS TO GET GOING IN EARNEST THIS EVENING...WITH INITIAL
FOCUS IN FAVORED WEST FLOW AREAS...WITH A SLIGHT SOUTHWARD TREND
EXPECTED DURING THE OVERNIGHT TOWARD THE M-32 CORRIDOR. SNOWFALL
AMOUNTS COULD BE QUITE IMPRESSIVE...WITH STRONG OMEGA CENTERED RIGHT
IN PRIME DGZ RIGHT THROUGH THE OVERNIGHT. DESPITE SOME FRAGMENTATION
OF FLAKES FROM VERY GUSTY WINDS (MORE ON THE WINDS TO
FOLLOW)...EXPECT SNOW TO LIQUID RATIOS TO PUSH 20 TO 1...PERHAPS
EVEN HIGHER IF STRONG LOW LEVEL CONVERGENCE UNDER BANDS HELP
SLACKING THE WIND FIELDS. SLIGHT SOUTHWARD DRIFT LOOKS TO BE THE
ONLY THING FROM PREVENTING SNOW AMOUNTS FROM GETTING TOO OUT OF
HAND. STILL...COULD EASILY SEE PARTS OF
CHARLEVOIX/ANTRIM/OTSEGO/EMMET/CHEBOYGAN COUNTIES EXCEEDING 8 INCHES
BY MORNING...WITH THE HIGHEST AMOUNTS JUST DOWNWIND OF LITTLE
TRAVERSE BAY. ANY SLOWER DRIFT OF BANDS THAN CURRENTLY ANTICIPATED
WILL RESULT IN LOCALLY HIGHER AMOUNTS. FURTHER SOUTH...COMPLETE LACK
OF A LAKE SUPERIOR CONNECTION REALLY SHORTENS THE EFFECTIVE FETCH
LENGTH. SO...DESPITE EXCELLENT INSTABILITY...JUST NOT SEEING THE
OPPORTUNITY FOR A WHOLE LOT OF ACCUMULATION ALONG AND SOUTH OF THE M-
72 CORRIDOR. HOWEVER...GUSTY WINDS OF 20 TO 30 MPH WILL MAKE FOR
SOME NASTY CONDITIONS...CREATING AREAS OF BLOWING AND DRIFTING SNOW
AND BRIEF PERIODS OF VERY LOW VISIBILITIES.
OFF LAKE SUPERIOR: INITIAL FOCUS THIS EVENING LOOKS TO REMAIN WEST
OF WHITEFISH POINT...REALLY TARGETING AREAS OVER NEAR MUNISING AND
SENEY. WINDS BEGIN TO SHIFT MORE W/NW LATE...BRINGING ACCUMULATING
SNOW BANDS INTO NORTHWEST CHIPPEWA COUNTY. LATER START AND SIGNALS
FOR BEST LOW LEVEL CONVERGENCE TO REMAIN OFF TO THE WEST SUGGESTS
LOWER SNOW TOTALS THAN THOSE TO THE SOUTH...WITH 2 TO 4 INCHES
EXPECTED BY MORNING. STRONG WINDS WILL PUSH BANDS FURTHER INLAND
THAN WHAT IS NORMAL...PERHAPS EVEN BRINGING PARTS OF NORTHWEST
MACKINAC COUNTY SEVERAL INCHES BY MORNING.
MORE SNOW WILL FALL IN ALL THE ABOVE AREAS TOMORROW...WITH SEVERAL
MORE INCHES EXPECTED (SEE LONG TERM SECTION BELOW).
HEADLINES: FOR NORTHERN LOWER...GIVEN GUSTY WINDS AND WHAT COULD BE
WIDESPREAD BLOWING SNOW EVEN OUTSIDE THE BETTER SNOW BANDS...HAVE
DECIDED TO FORGO THE SPECIFIC LAKE EFFECT HEADLINES FOR MORE GENERIC
WINTER WEATHER HEADLINES. HIGHEST SNOW TOTAL AREA MENTIONED EARLIER
WILL BE UPGRADED TO A WINTER STORM WARNING...STARTING AT 00Z THIS
EVENING RUNNING RIGHT THROUGH TUESDAY. WINTER WEATHER ADVISORIES
SHOULD DO FOR AREAS SOUTH OF M-72...AS WELL AS PARTS OF NORTHEAST
LOWER AS STRONG WINDS HELP PUSH WEAKENING BANDS FAR INLAND.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 331 AM EST MON NOV 17 2014
HIGH IMPACT WEATHER POTENTIAL...PLENTY OF SNOW AND COLD DURING THE
WORK WEEK. HEAVY LAKE EFFECT SNOW IN WNW/NW FLOW TUESDAY. SOME
POTENTIAL FOR HEAVY LAKE EFFECT SNOW WED NIGHT TO THU NIGHT.
TUESDAY...UPPER LOW WILL EJECT FROM NORTH OF LAKE HURON INTO EASTERN
QUEBEC. ONE TRAILING SHORTWAVE WILL CROSS CENTRAL LOWER MI IN THE
AFTERNOON...ANOTHER WEAK WAVE WILL DIG TOWARD EASTERN SUPERIOR. A
980MB SURFACE LOW STARTS THE MORNING IN CENTRAL QUEBEC...AND WILL
ADVANCE NE. SUBSTANTIAL TROFFING LINGERS ACROSS THE AREA EARLY IN
THE MORNING...THIS RELAXES AS THE UPPER LOW PULLS OUT...BUT LAKE-
INDUCED TROFFING REMAINS EVIDENT THRU THE DAY.
1000-850MB WINDS REMAIN STEADY-STATE IN THE MORNING...WNW INTO
NORTHERN LOWER AND NW INTO EASTERN UPPER. WINDS WILL BACK SOME
DURING THE AFTERNOON...BY EARLY EVENING WE WILL SEE A W FETCH INTO
NORTHERN LOWER AND WNW INTO EASTERN UPPER. PLENTY OF DEEP
MOISTURE...HIGH INVERSION HEIGHTS (TO NEARLY 500MB)...AND DELTA T/S
NEAR 20C SHOULD ENSURE RAMPAGING LAKE EFFECT SNOW IN THE MORNING
HOURS. IN THE AFTERNOON...THE INVERSION LOWERS TOWARD 700MB WITH
DRYING ALOFT. THAT WILL REDUCE SNOW INTENSITY SOMEWHAT...BUT BY AND
LARGE PARAMETERS AND STILL VERY FAVORABLE.
AS IS THE CASE FOR TONIGHT...THE LOW-LEVEL FLOW IS A LITTLE BACKED
COMPARED TO PREVIOUS RUNS. IN NORTHERN LOWER...THIS REQUIRES
ADJUSTING THE MAX SNOW TOTALS NORTHWARD SLIGHTLY.
CHARLEVOIX/ANTRIM/OTSEGO ARE THE MAIN ONES UNDER THE GUN...BUT THE
FETCH NOW SUPPORTS MORE SNOW IN SOUTHERN EMMET/CHEBOYGAN THAN IT
DOES IN NORTHERN KALKASKA/CRAWFORD. 5-9 INCHES STILL LIKES A GOOD
FORECAST FOR THE DAY IN THE HARDEST-HIT LOCALES...CENTERED ON
ELMIRA. 1-4 INCHES WORKS ELSEWHERE IN NW LOWER...WHERE THE FETCH IS
MUCH SHORTER AND HAS NO CONNECTION TO SUPERIOR.
IN EASTERN UPPER...THE BACKED FLOW OPENS UP MORE OF CHIPPEWA...BUT
SHOULD STILL KEEP THE STRONGEST BANDS WEST OF THE SAULT. BUT THINGS
ARE LOOKING CONSIDERABLY MORE FAVORABLE UP THERE...AND WILL INCREASE
WESTERN CHIP AND FAR NW MACK INTO THE 3-5 INCH RANGE.
MAX TEMPS WILL BE MAINLY IN THE 20S. HOWEVER...IN THE HIGH TERRAIN
IN THE SOUTH...WHERE MARINE MODIFICATION WILL BE SMALLER DUE TO THE
SHORTER FETCH...SOME PLACES (LIKE CAD) WILL LIKELY NOT ESCAPE THE
TEENS. (HARD TO BELIEVE IT/S ONLY MID-NOVEMBER.)
TUE NIGHT/WED...NOT MUCH REST FOR THE SNOW-WEARY. CLIPPER SHORTWAVE
WILL ADVANCE INTO THE WESTERN LAKES ON WED. ASSOCIATED SURFACE LOW
WILL ADVANCE FROM THE UPPER MS VALLEY TO NORTHERN LOWER MI ON WED.
LOW LEVEL FLOW WILL BACK TO THE SW TUE NIGHT...WITH MOISTENING
OVERNIGHT. SOME POTENTIAL FOR SOME SNEAKY 1-3 INCH ACCUMS OVER THE
TIP OF NORTHERN LOWER TUE EVENING. SYNOPTIC -SN MIGHT SNEAK INTO SW
SECTIONS LATE TUE NIGHT...BUT THE BULK OF THE THAT WILL WAIT UNTIL
WED. BY THEN...A SOUTH 1000-850MB FETCH SHOULD KEEP MOST OF THE LAKE-
INDUCED NONSENSE AT BAY...OTHER THAN ALONG THE SOUTH SHORE OF UPPER
MI (AND IT IS UNCERTAIN WHETHER SYNOPTIC PRECIP WILL MAKE IT THAT
FAR NORTH). THIS SYSTEM DOES NOT LOOK LIKE A MAJOR PROBLEM...1-2
INCHES...ESPECIALLY SOUTH OF M-32. MIN TEMPS TEENS TO PERHAPS HIGH
SINGLE DIGITS (YIKES). MAX TEMPS 20S.
REST OF THE FORECAST...POST-CLIPPER LAKE EFFECT SNOW WILL OCCUR WED
NIGHT INTO THU NIGHT...AIDED BY ANOTHER CLIPPER SHORTWAVE DROPPING
IN FROM THE NW. THE SET-UP FOR HEAVY SNOW LOOKS BETTER IN EASTERN
UPPER IN THIS EVENT...AS DEEPER MOISTURE WILL LINGER LONGER THERE VS
MID-LEVEL DRY AIR TRYING TO ENTRAIN INTO THE SOUTHER/CENTRAL LAKES.
REGARDLESS...LAKE EFFECT SHSN WILL AGAIN BE FAIRLY WIDESPREAD IN
BOTH PENINSULAS.
THOUGH THE MODELS TEND TO BE TOO FAST TO BREAK PATTERNS DOWN...ALL
MODELS HAVE THE CURRENT ONE FALL APART AFTER THIS LAST CLIPPER.
500MB FLOW BECOMES CONSIDERABLY MORE ZONAL...AND MORE SEASONABLE AIR
WILL FINALLY GET A CHANCE TO MOVE INTO THE REGION...ESPECIALLY BY
THE TAIL END OF THE WEEKEND. A SOUTHERN STREAM SYSTEM MOVING INTO
THE CENTRAL STATES WILL AMPLIFY WARM ADVECTION...AND INCREASE PRECIP
CHANCES BY SUNDAY. THIS ACTUALLY LOOKS TO BE MOSTLY RAIN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 112 PM EST MON NOV 17 2014
WINDS ARE NOW MORE WEST AND WITH IT, THE SNOW BANDS ARE ALIGNING
THEMSELVES WITH THE WIND SO THE MAIN ISSUE IS THE ENDING OF THE
HEAVY SNOW AT PLN AND FINDING THE RIGHT MIX OF PREVAILING AND
TEMPO GROUPS FOR TVC AND MBL. APN LOOKS TO BE IN GOOD SHAPE WITH
VFR CONDITIONS EXPECTED THROUGH 12Z TUES. WINDS LOOK TO TURN MORE
BACK FROM NNW TO NW BETWEEN 12Z AND 18Z SO THAT SNOW BANDS WILL
SHIFT THROUGH APN DURING THE MORNING. TO SUMMARIZE, PLN, TVC, AND
MBL, WILL HAVE MVFR CIGS AND VSBYS AS THE SNOW BANDS CONTINUE,
WITH OCCASIONAL VFR OR IFR DEPENDING ON BAND MOVEMENT AND
INTENSIFICATION. APN WILL MAINLY BE VFR, WITH OCCASIONAL MVFR
VSBYS AS SNOW BANDS MOVE OVER THE TAF SITE, BUT THAT WILL MAINLY
BE TUESDAY MORNING.
&&
.MARINE...
ISSUED AT 331 AM EST MON NOV 17 2014
STRONG SURGE OF CAA AND INCREASINGLY SHARP PRESSURE
GRADIENT WILL BRING VERY GUSTY WINDS BY LATER TODAY RIGHT THROUGH
TUESDAY. GREATEST IMPACT EXPECTED ACROSS NORTHERN LAKE
MICHIGAN...WHERE GALE FORCE WEST WINDS ARE EXPECTED TO DEVELOP
QUICKLY THIS EVENING. SCA CONDITIONS EXPECTED ELSEWHERE...ALTHOUGH
WILL NEED TO BE ON THE LOOKOUT FOR SOME GALE GUSTS ALONG THE
NORTHEAST LOWER COASTLINE. WINDS ARE EXPECTED TO SUBSIDE LATE
TUESDAY...AND ESPECIALLY TUESDAY NIGHT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST
TUESDAY FOR MIZ018-020-023-025>028-031>033.
WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM EST TUESDAY
FOR MIZ016-017-019-021-022.
WINTER WEATHER ADVISORY FROM 1 AM TO 7 PM EST TUESDAY FOR MIZ008.
LH...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR LMZ341.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 7 PM EST TUESDAY FOR
LMZ323-342-344>346.
LS...SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING TO 7 PM EST TUESDAY
FOR LSZ321-322.
&&
$$
UPDATE...JSL
SYNOPSIS...JAZ
SHORT TERM...MSB
LONG TERM...JAZ
AVIATION...JSL
MARINE...MSB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1217 PM EST MON NOV 17 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 411 AM EST MON NOV 17 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS INDICATE A DEEPENING
UPR TROF OVER CENTRAL NAMERICA WITH CLOSED H5 LO OVER ONTARIO JUST
NW OF LK SUP CAUSING 12HR H5 HGT FALLS UP TO 130M BTWN 16/12Z AND
17/00Z AT INL AND DRAWING H5 TEMPS CLOSE TO -40C S UNDER THE AXIS OF
LOWEST HGTS. BAND OF DPVA/DEEP LYR QVECTOR CNVGC/AXIS OF MID LVL
MSTR IN ADVANCE OF SHRTWV ROTATING ARND THE CLOSED LO IS CROSSING
UPR MI EARLY THIS MRNG...BUT DRYNESS OF AIRMASS SHOWN ON THE 00Z GRB
RAOB /PWAT 0.16 INCH IS 45 PCT OF NORMAL/ IS GREATLY LIMITING THE
COVERAGE/INTENSITY OF ACCOMPANYING LIGHT SN. THERE HAS BEEN SOME
LIGHT SN OVER THE FAR E NEAR NEWBERRY WITH A SW WIND OFF NRN LK
MI...BUT THE FLOW HAS NOT BACKED SUFFICIENTLY TO CAUSE THE HEAVIER
SN SHOWERS IN MACKINAC COUNTY TO IMPACT LUCE/SCHOOLCRAFT COUNTIES.
LOOKING TO THE W...THE 00Z H85/7 TEMPS WERE -17C/-27C AT INL /VS
-14C AND -16C AT GRB/. THE 00Z INL IS QUITE MOIST ALMOST UP TO H5
WITHIN A DEEP CYC FLOW. THERE IS A SHARP SFC WSHFT FM W TO NW ALONG
A SFC LO PRES TROF RUNNING THRU NRN MN INTO ADJACENT ONTARIO...WITH
SFC REPORTS SHOWING SOME MODERATE SN ALONG AND JUST BEHIND THIS
BNDRY.
MAIN FOCUS IN THE SHORT TERM WL BE ON LES AMOUNTS/GOING HEADLINES
ASSOCIATED WITH INCOMING COLD/MOIST AIRMASS. MADE NO CHANGES ATTM TO
HEADLINES ISSUED BY THE PREVIOUS SHIFT.
TODAY...AS CUTOFF H5 LO DEEPENS FURTHER AND SLIDES SLOWLY TO THE E
ACROSS UPR MI...SHARP CYC LLVL FLOW IS FCST TO SLOWLY ENVELOP THE
CWA W-E WITH A WSHFT FM WSW EARLY THIS MRNG TO NW BY LATE IN THE DAY
EXCEPT OVER THE SE CWA. THE SHARPER LLVL CNVGC WL ARRIVE OVER THE W
ARND 12Z AND RESULT IN INCRSG SN RATES DESPITE SOME DEEP LYR QVECTOR
DVGC IN THE WAKE OF THE SHRTWV ROTATING THRU THE UPR LKS EARLY THIS
MRNG. THE HIER RES MODELS HAVE CONSISTENTLY POINTED TO THE AREA ARND
ONTONAGON COUNTY AS THE FOCUS FOR THE SHARPEST CNVGC. GOING START
TIME OF 12Z FOR THE WARNINGS OVER THE W APPEARS TO BE ON TRACK.
SINCE THE RATHER LO UVV MAX IN THE ABSENCE OF DEEP LYR FORCING WL BE
CENTERED IN THE DGZ...EXPECT GOOD SN/WATER RATIOS IN EXCESS OF 20:1
DESPITE A DGZ DEPTH OF ONLY ABOUT 3K FT AND INCRSG WINDS THAT WOULD
TEND TO FRAGMENT THE SN FLAKES. WITH SOME INCRSG DEEP LYR QVECTOR
CNVGC/UVV OVER THE W HALF LATER IN THE DAY UNDER THE DEEPENING UPR
TROF AXIS...FCST SDNGS ALSO INDICATE INCRSG DEEP MSTR THRU THE DAY
PER THE 00Z INL RAOB WITH EQUILIBRIUM LVLS APRCHG 10K FT OVER THE BY
LATER IN THE DAY AS H85/7 TEMPS DIP TO -16C TO -17C/-27C. INCRSG NW
WINDS/DESTABILIZATION WL RESULT IN GUSTY SFC WINDS AND SOME BLSN AS
WELL. FARTHER TO THE E...THE LLVL FLOW IS FCST TO BE OUT OF THE W
MOST OF THE DAY...SO THE SN SHOWERS THERE SHOULD BE MAINLY CONFINED
TO THE LK SHORE UNTIL AT LEAST 21Z...WHEN THE FASTER HI RES CNDN
MODEL SHOWS THE ARRIVAL OF SHARPER CYC FLOW/ WSHFT TO THE NW. FCST
LES WARNINGS FOR ALGER/NRN SCHOOLCRAFT COUNTIES BEGINS AT 21Z...SO
WL NOT CHANGE THIS START TIME. THERE SHOULD BE NOTHING MORE THAN
FLURRIES/LIGHT SN SHOWERS OVER THE SCENTRAL WITH DOWNSLOPE FLOW.
TNGT...UPR TROF/AXIS OF DEEP LYR QVECTOR CNVGC AND MSTR/SFC LO PRES
TROF AND CYC WSHFT TO THE NW ARE PROGGED TO DRIFT SLOWLY E. THESE
TRENDS WL RESULT IN INCRSG POPS/SN RATES IN THE NW SN BELTS MAINLY E
OF MARQUETTE. THE 00Z NAM AND ESPECIALLY THE HI RES CNDN MODEL HINT
LK NIPIGON MOISTENING WL GREATLY ENHANCE SN RATES OVER ALGER/NRN
SCHOOLCRAFT COUNTIES...SO THE GOING WRNGS APPEAR ON TRACK. AS WL BE
THE CASE TODAY OVER THE W...HI EQUILIBRIUM LVL AND FAVORABLE UVV MAX
WITHIN THE DGZ WL BE ENHANCING FACTORS FOR SN RATES IN THIS AREA.
ALTHOUGH THE DEPARTURE OF THE DYANAMIC SUPPORT/VERY DEEP MSTR MAY
SLOW DOWN THE HEAVY SN RATES OVER THE W BY THE OVERNGT HRS...
LINGERING CYC NW BACKING TOWARD THE WNW OVER THE FAR W TOWARD 12Z WL
CONTINUE WIDESPREAD SN SHOWERS/CATEGORICAL POPS IN THE FAVORED SN
BELTS THERE. ALTHOUGH THE EXPECTED NW FLOW IS NOT FAVORABLE FOR
MARQUETTE COUNTY...WL CONTINUE THE ADVY FOR THIS AREA GIVEN
POTENTIAL FOR HIER WINDS NEAR THE LK SHORE AND HEAVIER SN IN THE
EASTERN PART OF THE COUNTY. ONCE AGAIN...THE LIGHTEST AND LEAST
WIDESPREAD SN SHOWERS WL BE OVER THE SCENTRAL.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 646 AM EST MON NOV 17 2014
UPPER TROUGH THAT IS IN THE PROCESS OF MOVING OVER THE AREA TODAY
WILL BE STARTING TO MOVE OUT OF THE AREA WHILE A WEAK SURFACE RIDGE
OVER THE NORTHERN PLAINS SHIFTS EAST INTO THE UPPER GREAT LAKES
REGION. MODERATE TO HEAVY SNOW WILL BE ONGOING OVER PORTIONS OF THE
CWA...ESPECIALLY OVER THE EAST (ALGER AND NORTHERN SCHOOLCRAFT
COUNTIES) WHERE THE NORTHWEST FLOW LAKE EFFECT WILL BE AIDED BY LOW
LEVEL WINDS STARTING TO BACK IN RESPONSE TO THE SURFACE RIDGE AND
INCREASING CONVERGENCE. EXPECT THE FAVORABLE CONDITIONS TO CONTINUE
THROUGH THE MORNING OVER THE EAST...BEFORE THE DRYING AND LOWERING
INVERSION HEIGHTS SEEN OVER THE WEST DURING THE MORNING...MOVES
INTO THE AREA AND DIMINISHES THE INTENSITY OF THE LAKE EFFECT.
WINDS WILL ALSO BE STEADILY BACKING THROUGH THE DAY...TO THE
SOUTHWEST OVER THE WESTERN CWA AND WESTERLY OVER THE EASTERN CWA BY
THE EVENING HOURS TUESDAY. THUS...WOULD EXPECT TRANSIENT BANDS
BECOMING FOCUSED OVER THE KEWEENAW PENINSULA AND NEAR LAKE SUPERIOR
EAST OF PICTURED ROCKS. AS FOR SNOWFALL ACCUMULATION...HAVE ANOTHER
3-5 INCHES NORTHWEST OF A LINE FROM DEERTON TO MANISTIQUE AND
ANOTHER 1-3 INCHES OVER THE TRADITIONAL AREAS OVER THE WEST.
TUESDAY EVENING...COULD SEE ANOTHER 1-2 INCHES AS THE LAKE EFFECT
TRANSITIONS NORTH ACROSS THE KEWEENAW PENINSULA BEFORE IT MOVES
OFFSHORE.
ALSO ON TUESDAY NIGHT...A SHORTWAVE WILL DIVE SOUTHEAST FROM
CENTRAL CANADA...THROUGH NORTHERN MINNESOTA AND INTO WISCONSIN. AT
THE SURFACE...A BROAD TROUGH WILL QUICKLY DROP INTO THE AREA AND
BRING MORE VARIABLE LOW LEVEL WINDS TO THE AREA. WILL CONTINUE TO
SHOW SLIGHT AND LOW CHANCE POPS FOR AREAS NEAR THE WISCONSIN BORDER
LATE TUESDAY NIGHT. THIS COULD CONTINUE INTO WEDNESDAY FOR MUCH OF
THE AREA AS BROAD MID LEVEL Q-VECTOR CONVERGENCE CONTINUES ALTHOUGH
MUCH OF THE AREA WILL BE BETWEEN THE INITIAL SHORTWAVE MOVING INTO
LOWER MICHIGAN AND THE SECONDARY SHORTWAVE DROPPING INTO NORTHWEST
WISCONSIN LATE WEDNESDAY AFTERNOON. THUS...WILL SHOW SOME POTENTIAL
FOR LIGHT SNOW SHOWERS ON WEDNESDAY. ALSO ON WEDNESDAY...COULD SEE
LAKE EFFECT OFF LAKE MICHIGAN OVER SOUTHEAST LUCE COUNTY ON
WEDNESDAY AFTERNOON AS LOW LEVEL WINDS BACK FAR ENOUGH TO THE
SOUTH-SOUTHWEST TO PUSH THE BAND INTO THAT AREA. THEN AS WINDS SHIFT
TO THE WEST-NORTHWEST BEHIND A SECONDARY SURFACE TROUGH...EXPECT THE
LAKE EFFECT SNOW TO PICKUP IN THE KEWEENAW FIRST (WEDNESDAY
AFTERNOON) AND THEN SPREAD OVER THE REST OF THE NORMAL
WEST-NORTHWEST FAVORED LOCATIONS OVER THE WEST DURING THE EVENING
AND EAST OVERNIGHT. WINDS ON THURSDAY WILL DEPEND ON THE TRAILING
SURFACE TROUGH ATTEMPTING TO HOLD OVER EASTERN LAKE SUPERIOR. MODELS
VARY ON ITS LOCATION LATE WEDNESDAY NIGHT INTO THURSDAY AND HOW
QUICKLY IT DEPARTS. DUE TO THESE DIFFERENCES...THE FINER DETAILS ARE
HARD TO PIN DOWN AND WILL FOCUS ON GENERAL NORTHWEST WIND LAKE
EFFECT FOR THE TIME BEING. STILL EXPECT VERY FAVORABLE LAKE EFFECT
CONDITIONS (DELTA-T VALUES AROUND 23) BUT LAKE INDUCED EQUILIBRIUM
VALUES WILL BE 5KFT LOWER THAN TONIGHT (UP TO 13KFT) AND LAKE
INDUCED CAPE VALUES WILL PEAK AROUND 800 J/KG. WINDS DO LOOK TO BE
WEAKER DURING THIS PERIOD...WHICH WOULD LEAD TO LESS FRACTURING OF
THE DENDRITES...BUT DO HAVE A LITTLE CONCERN THAT THE TOP HALF OF
THE CLOUD WILL BE ABOVE THE DGZ AND SUPPORT MORE COLUMNS IN THE SNOW
AND LEAD TO LOWER RATIOS. THUS...WILL STICK WITH SNOW RATIOS AROUND
OR JUST ABOVE 20-1 AT THIS POINT AND WILL BE ABLE TO FINE TUNE WITH
FUTURE SHIFTS. THIS PRODUCES SNOWFALL AMOUNTS OF 5 TO 11 INCHES IN
THE NORTHWEST TO WEST-NORTHWEST WIND SNOW BELTS FOR WEDNESDAY
AFTERNOON INTO THURSDAY EVENING. CURRENT THINKING IS A GENERAL LES
ADVISORY WILL BE NEEDED AT SOME POINT (UNLESS INCREASED CONVERGENCE
OCCURS ALONG THE TRAILING SURFACE TROUGH) AND WILL CONTINUE TO
HIGHLIGHT IN THE HWO/EHWO.
UPPER TROUGH WILL BEGIN TO SHIFT EAST AND OUT OF THE AREA ON
THURSDAY...ALLOWING AN UPPER RIDGE TO BUILD TOWARDS THE AREA
THURSDAY NIGHT AND IN TURN A SURFACE RIDGE. THIS WILL GRADUALLY
WEAKEN THE LAKE EFFECT ON THURSDAY NIGHT INTO FRIDAY AS INVERSION
HEIGHTS STEADILY FALL AND WINDS BACK TO THE WEST AND EVENTUALLY
SOUTHWEST. THE HIGH PRESSURE RIDGE WILL CONTINUE EAST ON FRIDAY
NIGHT...AS THE CENTER OF THE HIGH MOVES INTO THE MID ATLANTIC
STATES. WITH THE MORE ZONAL FLOW ALOFT...EXPECT TEMPERATURES TO
BEGIN TO MODERATE HEADING INTO THE WEEKEND BUT STILL BE BELOW
NORMAL FOR THIS TIME OF YEAR. MODELS STILL DON/T HAVE MUCH
CONSISTENCY FOR THIS WEEKEND...AS THEY AREA STRUGGLING WITH THE
TIMING/LOCATION OF THE INITIAL SHORTWAVE EJECTING NORTHEAST OUT OF
THE UPPER TROUGH OVER THE ROCKIES. THUS...WILL FOLLOW A GENERAL
MODEL CONSENSUS AND BRING SLIGHT CHANCE POPS INTO THE AREA FOR
SATURDAY NIGHT AND CHANCE ON SUNDAY. WITH THE WARM AIR WRAPPING
NORTHWARD...DID GO WITH MAINLY RAIN ON SUNDAY OVER THE EASTERN U.P.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1216 PM EST MON NOV 17 2014
DEEP MID/UPPER LEVEL TROF AND ASSOCIATED DEEP MOISTURE PUSHING
ACROSS THE AREA WILL LEAD TO HEAVIER LAKE EFFECT SNOW SHOWERS
AFFECTING KIWD/KCMX UNDER NW FLOW. COMBINATION OF SNOW AND GUSTY NW
WINDS CREATING BLSN WILL LIKELY RESULT IN LIFR CONDITIONS PREVAILING
AT BOTH TERMINALS. AS DEEPER MOISTURE BEGINS TO EXIT...EXPECT
IMPROVEMENT TO IFR LATE TONIGHT/EARLY TUE MORNING AND THEN TO MVFR
BY TUE AFTN. AT KSAW...NW WIND DIRECTION WILL NOT BE FAVORABLE FOR
ANYTHING MORE THAN -SHSN AT TIMES. MVFR CIGS WILL DEVELOP THIS AFTN
AND CONTINUE THRU THE REMAINDER OF THE FCST PERIOD. THERE MAY BE A
FEW PERIODS OF MVFR VIS IN -SHSN LATER THIS AFTN.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 646 AM EST MON NOV 17 2014
LOW PRESSURE OVER FAR NORTHERN LAKE SUPERIOR WILL SHIFT EAST
TODAY...SWEEPING A SURFACE TROUGH SOUTHEAST ACROSS LAKE SUPERIOR
TODAY. BEHIND THE TROUGH...LOOK FOR GUSTS TO INCREASE TO GALES OF
35-40KTS OVER PORTIONS OF W LAKE SUPERIOR THIS AFTERNOON...BEFORE
EXPANDING TO THE E HALF OF LAKE SUPERIOR THIS EVENING THROUGH
EARLY TUESDAY. THE TIMING OF THE GALE WARNING WAS IN GOOD SHAPE
AND WILL CONTINUE. A TROUGH WILL THEN LINGER ACROSS LAKE SUPERIOR
THROUGH TUESDAY MORNING...BEFORE BRIEFLY BEING REPLACED BY A RIDGE
TUESDAY AFTERNOON AND EVENING. ANOTHER TROUGH OVER N MANITOBA ON
TUESDAY WILL SLIDE ACROSS THE UPPER GREAT LAKES LATE TUESDAY NIGHT
THROUGH WEDNESDAY...BEFORE EXITING ACROSS THE ONTARIO AND QUEBEC
BORDER THURSDAY MORNING. A FEW NORTHWEST GALE FORCE GUSTS TO 35
KNOTS ARE POSSIBLE OVER EASTERN LAKE SUPERIOR LATE WEDNESDAY
NIGHT INTO THURSDAY MORNING. HIGH PRESSURE OVER THE N PLAINS ON
THURSDAY WILL DIVE ACROSS THE OHIO VALLEY LATE FRIDAY...EXTENDING A
RIDGE OVER THE UPPER GREAT LAKES ON FRIDAY AND DIMINISHING WINDS
BELOW 25 KNOTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST TUESDAY FOR MIZ004-084.
LAKE EFFECT SNOW WARNING FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR MIZ006-085.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST /NOON CST/ TUESDAY FOR
MIZ001>003-009.
LAKE EFFECT SNOW ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
TUESDAY FOR MIZ007.
LAKE EFFECT SNOW ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM EST
TUESDAY FOR MIZ005.
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 1 PM EST
TUESDAY FOR MIZ014.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TO 1 PM EST TUESDAY FOR LSZ251-267.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 1 PM EST TUESDAY FOR
LSZ248>250-265-266.
GALE WARNING UNTIL 9 AM EST TUESDAY FOR LSZ264.
GALE WARNING UNTIL 4 AM EST /3 AM CST/ TUESDAY FOR LSZ240>242-
263.
GALE WARNING UNTIL 7 AM EST TUESDAY FOR LSZ243>245.
GALE WARNING UNTIL 1 AM EST /MIDNIGHT CST/ TUESDAY FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS DULUTH MN
353 PM CST MON NOV 17 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 352 PM CST MON NOV 17 2014
AT 352 PM...SNOW HAD STARTED TO INTENSIFY ALONG PORTIONS OF THE
GOGEBIC RANGE OF IRON COUNTY. OUR SNOWFALL OBSERVER IN GILE
REPORTED 1 INCH OF NEW SNOWFALL TODAY...BUT IT HAD JUST RECENTLY
STARTED TO INTENSIFY. FURTHER WEST...4 INCHES OF SNOW HAD FALLEN
IN THE IRON RIVER AREA...FROM PERSISTENT LIGHT SNOW THAT HAD SET
UP IN THAT AREA EARLIER TODAY. THE REMAINDER OF THE CWA WAS
GENERALLY SEEING PARTLY TO MOSTLY CLOUDY SKIES AND SCATTERED SNOW
SHOWERS. ASIDE FROM THE SOUTH SHORE THERE WAS LITTLE SNOW
ACCUMULATION.
THE MAIN FOCUS FOR TONIGHT IS DEFINITELY THE SOUTH SHORE LAKE
EFFECT SNOWFALL EVENT. FORECAST SOUNDINGS LOOK QUITE FAVORABLE
OVERNIGHT...ALBEIT A BIT TOO WESTERLY FOR PORTIONS OF THE NIGHT.
HIGH RESOLUTION MODELING...INCLUDING THE HRRR AND THE WRF INDICATE
SNOW SQUALLS WILL BECOME INTENSE DURING THE EVENING...AND THEN
REMAIN THAT WAY FOR MUCH OF THE NIGHT. FORECAST SOUNDINGS AND
BUFKIT ANALYSIS INDICATES EXTREME INSTABILITY AND INVERSION
HEIGHTS OF UP TO AN AMAZING 5 KM. INVERSION HEIGHTS CRASH DURING
THE DAY TUESDAY...BUT WINDS WILL BECOME MORE WESTERLY AS THE DAY
WEARS ON...DRAMATICALLY REDUCING THE LAKE EFFECT POTENTIAL. WILL
CONTINUE WITH THE LAKE EFFECT SNOW WARNING FOR THE GOGEBIC RANGE
AREA...FOR A TOTAL OF 8 TO 14 INCHES. FURTHER WEST...WILL CONTINUE
THE ADVISORY FOR BAYFIELD COUNTY...WITH GENERALLY 4 TO 8 INCHES.
LOWS TONIGHT WILL BE THE OTHER ISSUE. WIND CHILL READINGS MAY DROP
TO AS LOW AS 15 TO 20 BELOW IN MUCH OF NORTHEASTERN MINNESOTA
OVERNIGHT. WINDS WILL REMAIN A BIT GUSTY THROUGHOUT THE NIGHT.
OTHERWISE OVERNIGHT...WE SHOULD SEE PARTLY TO MOSTLY CLOUDY SKIES
AND ISOLATED TO SCATTERED SNOW SHOWERS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 352 PM CST MON NOV 17 2014
COLD AND CLOUDY WEATHER TO BEGIN THE LONG TERM PERIOD WITH A BRIEF
WARM UP EXPECTED THIS WEEKEND. PRECIPITATION CHANCES ARE LOW OVERALL
WITH A FEW CHANCES FOR SNOW ON WEDNESDAY AND LATE IN THE WEEKEND.
WEDNESDAY/THURSDAY...GOOD CHANCE FOR LIGHT ACCUMULATIONS ON
WEDNESDAY GENERALLY NORTH OF HIGHWAY 2...WITH THE BEST CHANCE FROM
INTERNATIONAL FALLS EAST THROUGH THE TIP OF THE ARROWHEAD REGION.
THIS WILL BE CAUSED BY AN ELONGATED MID-LEVEL DISTURBANCE MOVING
SOUTH OUT OF MANITOBA ALONG A DEEPENING UPPER LOW. THIS UPPER LOW
WILL QUICKLY MOVE SOUTHEAST OVER THE NORTHERN PART OF THE GREAT
LAKES REGION ON THURSDAY. THIS WILL LEAVE NORTHERN MINNESOTA AND
NORTHERN WISCONSIN IN A STRONG NORTHWESTERLY FLOW AT UPPER LEVELS
/AROUND 80 KTS AT H5/ AND WITH AROUND 24 HOURS OF COLD /850MB TEMPS
AS COLD AS -20 C/ NORTHWEST FLOW AT LOW LEVELS THERE MAY BE SOME
MODERATE TO HEAVY LAKE EFFECT SNOWFALL ALONG THE SOUTH SHORE. SKIES
WILL BE OVERCAST MOST OF THE TIME...WITH SOME CLEARING ON THURSDAY
SOUTH OF HIGHWAY 2.
FRIDAY/SATURDAY/SUNDAY...WARMING UP AS HIGH PRESSURE MOVES EAST THROUGH
THE MIDWEST LATE THURS/EARLY FRI RESULTING IN SOUTHWEST FLOW AT
MID/LOW LEVELS FRI/SAT. 850 MB TEMPS RISE AS WARM AS JUST ABOVE
FREEZING OVER THE WEEKEND...AND WITH PARTLY TO MOSTLY SUNNY SKIES
SURFACE TEMPS WILL WARM UP TO NEAR FREEZING FRI/SAT AND LIKELY ABOVE
FREEZING INTO THE MID/UPPER 30S ON SUNDAY...WHICH IS NEAR TO ABOVE
NORMAL FOR MUCH OF THE NORTHLAND. OVER THE WEEKEND AN UPPER LEVEL
DISTURBANCE WILL DEEPEN OVER THE SOUTHERN PLAINS AND MOVE NORTH UP
THE MISSISSIPPI RIVER VALLEY TO THE CENTRAL GREAT LAKES. MODEL
GUIDANCE STILL VARIES WIDELY IN PLACEMENT OF THE UPPER LOW...AND IF
IT TRENDS WESTWARD AS THE ECMWF IS HINTING THEN SUNDAY MAY BE COOLER
AND CLOUDIER THAN CURRENTLY FORECAST WITH LIGHT SNOW POSSIBLY MIXED
WITH RAIN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1139 AM CST MON NOV 17 2014
MVFR TO VFR CONDITIONS AT TAF SITES ACROSS THE REGION DUE TO LOW
CEILINGS AND OFF AND ON SNOW SHOWERS BRIEFLY LOWERING VIS. SNOWFALL
WILL TAPER OFF THIS AFTERNOON AND CEILINGS SHOULD RISE TO VFR FOR A
FEW HOURS BEFORE DROPPING TO MVFR OVERNIGHT TONIGHT AT MOST
SITES...WITH HIGHEST CONFIDENCE IN MVFR CIGS AT BRD AND HYR. WINDS
THIS AFTERNOON ARE OUT OF THE NORTHWEST GUSTING TO NEAR 25
KTS...WHICH IS CAUSING BLOWING SNOW AND REDUCED VISIBILITY AT A FEW
SPOTS. WINDS WILL WEAKEN THIS EVENING AND BECOME LIGHT OUT OF THE
WEST AT 5 TO 10 KTS OVERNIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 2 17 6 20 / 30 0 40 20
INL 0 18 7 19 / 30 20 40 40
BRD 0 16 7 18 / 10 0 40 10
HYR 2 16 3 20 / 30 10 60 30
ASX 7 19 7 23 / 60 30 40 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...LAKE EFFECT SNOW WARNING UNTIL NOON CST TUESDAY FOR WIZ003-004.
LAKE EFFECT SNOW ADVISORY UNTIL NOON CST TUESDAY FOR WIZ002.
LS...GALE WARNING UNTIL 3 AM CST TUESDAY FOR LSZ121-144>148.
SMALL CRAFT ADVISORY UNTIL 11 AM CST TUESDAY FOR LSZ140>143.
&&
$$
SHORT TERM...DAP
LONG TERM...MOORE
AVIATION...MOORE
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1204 PM CST MON NOV 17 2014
.UPDATE...
ISSUED AT 1204 AM CST MON NOV 17 2014
ISOLATED FLURRIES AND LIGHT SNOW SHOWERS HAVE DEVELOPED ACROSS
WESTERN AND CENTRAL NORTH DAKOTA. ADDED ISOLATED FLURRIES TO THE
AFTERNOON FORECAST AS A RESULT. THE REMAINING WEATHER ELEMENTS ARE
IN GOOD SHAPE. THE UPDATED PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 837 AM CST MON NOV 17 2014
NO MAJOR CHANGES WERE MADE TO THE ONGOING FORECAST. ONLY ADJUSTED
THE HOURLY SENSIBLE WEATHER GRIDS TO COME MORE IN LINE WITH THE
CURRENT OBS/TRENDS. THE UPDATED PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 644 AM CST MON NOV 17 2014
NO SIGNIFICANT CHANGES REQUIRED WITH THIS FORECAST UPDATE OTHER
THAN TO BLEND TO OBSERVED TRENDS THROUGH 12 UTC WITH A FRIGID DAY
EXPECTED AREA WIDE IN THE WAKE OF THE SUNDAY REINFORCING COLD
FRONT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 334 AM CST MON NOV 17 2014
HUDSON BAY UPPER LOW WITH SUCCESSIVE SHORTWAVE TROUGHS ROTATING
AROUND HAS CARVED OUT A SIGNIFICANT UPPER TROUGH EXTENDING SOUTH
INTO THE MIDWEST AND SOUTHERN PLAINS PER LATEST WATER VAPOR
IMAGERY. NORTHERLY FLOW INTO NORTH DAKOTA WITH ANOTHER MINOR
SHORTWAVE NOW LOCATED JUST WEST OF LAKE WINNIPEG IS FORECAST TO
REACH INTO THE BISMARCK VICINITY BY 18Z TODAY. THE LATEST
FOG/STRATUS LOOP SHOWS CLOUDS AND FLURRIES OVER THE
SOUTHWEST...WHICH EXTENDS ACROSS MOST OF EASTERN MONTANA. FARTHER
UPSTREAM CLOSER TO THE LOCATION OF THE INCOMING SHORTWAVE...QUITE
A BIT OF CLOUDS PUSHING SOUTH. THE LATEST HRRR REINFORCES CLOUDS
ESPECIALLY IN THE WEST...BUT THINK THE CENTRAL WILL ALSO CLOUD UP
DURING THE LATE MORNING AND EARLY AFTERNOON. THE HIGH RESOLUTION
ARW AND NMM MODELS CONTINUE WITH THE FLURRIES WEST THROUGH 18Z
TODAY AND HAVE FOLLOWED THIS AS THEY ARE VERIFYING THE BEST EARLY
THIS MORNING WITH THE CURRENT ACTIVITY. WARM AIR ADVECTION
COMMENCES MONDAY NIGHT WITH A PUSH OF H7-H5 MOISTURE. THIS WILL
PROGRESS FROM WEST TO EAST OVERNIGHT RESULTING IN PARTLY CLOUDY
CONDITIONS. HIGHS TODAY WILL RANGE FROM 10F TO 15F WITH OVERNIGHT
LOWS BETWEEN 3 BELOW ZERO TO 3 ABOVE.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 334 AM CST MON NOV 17 2014
A POTENTIAL MODERATION IN TEMPERATURES LATE THIS WEEK HIGHLIGHTS
THE EXTENDED FORECAST.
THE 00 UTC SUITE IS IN AGREEMENT ON THE ANOMALOUS HIGH AMPLITUDE
UPPER LEVEL PATTERN ACROSS NORTH AMERICA BREAKING DOWN TO A NEAR
ZONAL PATTERN BY NEXT WEEKEND IN A BROAD VERY LOW AMPLITUDE
TROUGH. THIS WOULD SIGNAL A RECOVERY FROM THE ARCTIC TEMPERATURES
TO STILL BELOW NORMAL...YET MORE TOLERABLE HIGHS NEAR FREEZING
FRIDAY INTO THE WEEKEND. THE EXTENDED FORECAST LOOKS TO BE LARGELY
PRECIPITATION FREE...WITH SPLIT FLOW DEVELOPING AND THE LACK OF
MOISTURE RECOVERY FROM THE ARCTIC AIRMASS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1204 AM CST MON NOV 17 2014
VFR/TEMPO MVFR CONDITIONS IN CIGS AND FLURRIES WILL CONTINUE OVER
WESTERN AND CENTRAL NORTH DAKOTA THIS AFTERNOON. CONDITIONS SHOULD
IMPROVE TO VFR OVERNIGHT THROUGH TUESDAY MORNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...KS
LONG TERM...AYD
AVIATION...TM
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1208 PM CST MON NOV 17 2014
.DISCUSSION...
UPDATED FOR THE 18Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 1037 AM CST MON NOV 17 2014/
UPDATE...
STARTING TO SEE WHAT MAY BE THE BEGINNING OF OUR AFTERNOON
FLURRIES DEVELOPING OVER MISSOURI...SO WILL HANG ON TO THE
PREVIOUS FORECAST. TEMPERATURES HAVE WARMED TO NEAR OR EVEN
SLIGHTLY FREEZING AT THE WARMEST LOCATIONS ACROSS THE
MIDSOUTH...BUT NORTH WIND WILL KEEP CONDITIONS FROM WARMING MUCH
MORE TODAY. STAY WARM.
&&
.PREV DISCUSSION... /ISSUED 441 AM CST MON NOV 17 2014/
CURRENTLY...BANDS OF LIGHT SNOW ARE MOVING ACROSS THE NORTHERN
HALF OF THE MIDSOUTH. SOME SLEET HAS BEEN MIXED IN AROUND THE
MEMPHIS AREA. DECIDED TO GO AHEAD AND EXPAND THE ADVISORY TO
INCLUDE MOST OF THE I-40 CORRIDOR SINCE BRIDGES AND OVERPASSES
COULD BECOME SLICK AHEAD OF THE MONDAY MORNING COMMUTE AS TEMPS
FALL BELOW FREEZING. LATEST HRRR PULLS THESE BANDS NE AND OUT OF
THE AREA BY 7 OR 8 AM. MEANWHILE RAIN HAS CLEARED OUT OF NORTH
MISSISSIPPI.
TODAY...PRECIP WILL QUICKLY EXIT THIS MORNING AND SOME TEMPORARY
CLEARING WILL OCCUR. MEANWHILE MUCH COLDER AIR WILL FILTER IN ON
BRISK NW WINDS. EXPECT COLD AIR STRATOCU TO DEVELOP AND MOVE INTO
THE AREA FROM THE NORTH AS 850 MB TEMPS DROP TO -14C AS FAR SOUTH
AS THE I-40 CORRIDOR THIS AFTERNOON. THE NAM 925 MB RH FIELDS
DEPICT THIS WELL. SOME FLURRIES ARE ALSO POSSIBLE ACROSS THE
NORTH HALF THIS AFTERNOON. TEMPS WILL BE VERY COLD WITH HIGHS
AROUND 30 NEAR THE KY/MO BORDERS TO AROUND 40 SOUTH.
TONIGHT THROUGH TUESDAY NIGHT...ARCTIC HIGH PRESSURE SETTLES OVER
THE REGION. VERY COLD TONIGHT WITH TEMPS DROPPING WELL INTO THE
TEENS. WOULD GO COLDER THAN GUIDANCE EXCEPT THERE IS SOME
GRADIENT LEFT ACROSS THE AREA WHICH WILL KEEP WINDS UP A BIT. THIS
OF COURSE WILL CAUSE WIND CHILLS TO DROPS INTO THE SINGLE DIGITS
ACROSS THE NORTH HALF BY TUESDAY MORNING. TUESDAY WILL BE VERY
COLD WITH UPPER 20S NEAR PARIS TO MID 30S SOUTH. THIS IS PUSHING
35 DEGREES BELOW NORMAL. TEMPS WILL FALL QUICKLY INTO THE 20S
TUESDAY EVENING AND THEN LEVEL OFF AS SOUTH WINDS DEVELOP AHEAD OF
AN APPROACHING SURFACE TROF.
WEDNESDAY AND WEDNESDAY NIGHT...SURFACE TROF MOVES THROUGH WITH
WARMER SW WINDS ACROSS THE AREA AND TEMPS SHOULD CLIMB INTO THE
UPPER 40S AND LOWER 50S...WHICH THOUGH PLEASANT SOUNDING IS STILL
10 DEGREES BELOW NORMAL. WEAK HIGH PRESSURE PREVAILS WEDNESDAY
NIGHT WITH WITH LOWS IN THE 20S AND 30S.
THURSDAY THROUGH THE WEEKEND...00Z MEDIUM RANGE MODELS ARE IN
MUCH BETTER AGREEMENT TODAY. A MAJOR PATTERN SHIFT WILL OCCUR AS
THE COLD UPPER TROF PUSHES EAST AND THE UPPER FLOW BECOME ZONAL BY
THE END OF THE WEEK. AN OVERRUNNING PATTERN SETS UP AS A
DISTURBANCE MOVES THROUGH IN THE ZONAL FLOW ALOFT. AS A RESULT
EXPECT RAIN CHANCES THURSDAY NIGHT AND FRIDAY. BY SATURDAY A
BROAD UPPER RIDGE WILL BUILD OVER THE AREA AS A POTENT MID LEVEL
TROF PUSHES OUT OF THE SW U.S. INTO TEXAS. AS A RESULT EXPECT
WARMER AIR TO START MOVING NORTH INTO THE MIDSOUTH WITH HIGHS IN
THE 50S AND 60S. BY SAT NIGHT AND SUNDAY THE UPPER TROF WILL PUSH
THROUGH WITH SHOWERS AND THUNDERSTORMS LIKELY.
SJM
&&
.AVIATION...
18Z TAF CYCLE
VFR CIGS AND VSBYS WILL CONTINUE FOR THE NEXT COUPLE OF HOURS AT
ALL SITES. MVFR CIGS WILL LIKELY DEVELOP AT KJBR AND KMKL BY MID
AFTERNOON AS STRATOCUMULUS DEVELOPS. THERE MAY BE ENOUGH
INSTABILITY WITHIN FAVORABLE DENDRITIC ZONE TO SUPPORT SOME SNOW
SHOWERS AFTER 21Z AT KMKL. KEPT VSBYS P6SM AT KMKL FOR AFTER
21Z...BUT THIS WILL NEED TO BE MONITORED CLOSELY AS HEAVIER SNOW
SHOWERS COULD REDUCE VSBYS. ELSEWHERE...A FEW FLURRIES WILL BE
POSSIBLE BUT NOT EXPECTING ANY VSBY REDUCTIONS. VFR CIGS WILL
PREVAIL AT BOTH KMEM AND KTUP THROUGH THE AFTERNOON AND EARLY
EVENING. GUSTY NORTHWEST WINDS WILL CONTINUE AT ALL SITES THROUGH
EARLY EVENING.
STRATOCUMULUS WILL SCATTER OUT THIS EVENING WITH SKIES CLEARING AT
ALL LOCATIONS OVERNIGHT. WINDS WILL ALSO DIMINISH THROUGH THE
EVENING HOURS TO 6 KTS OR LESS FROM THE NORTHWEST.
CLEAR SKIES WILL PERSIST AT ALL SITES TUESDAY MORNING WITH WINDS
INCREASING TO BETWEEN 8-10 KTS FROM THE WEST NORTHWEST.
JLH
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1037 AM CST MON NOV 17 2014
.UPDATE...
STARTING TO SEE WHAT MAY BE THE BEGINNING OF OUR AFTERNOON
FLURRIES DEVELOPING OVER MISSOURI...SO WILL HANG ON TO THE
PREVIOUS FORECAST. TEMPERATURES HAVE WARMED TO NEAR OR EVEN
SLIGHTLY FREEZING AT THE WARMEST LOCATIONS ACROSS THE
MIDSOUTH...BUT NORTH WIND WILL KEEP CONDITIONS FROM WARMING MUCH
MORE TODAY. STAY WARM.
&&
.PREV DISCUSSION... /ISSUED 714 AM CST MON NOV 17 2014/
DISCUSSION...
WIND WEATHER ADVISORIES HAVE BEEN CANCELLED AS PRECIPITATION HAS
MOVED EAST.
PREV DISCUSSION... /ISSUED 441 AM CST MON NOV 17 2014/
CURRENTLY...BANDS OF LIGHT SNOW ARE MOVING ACROSS THE NORTHERN
HALF OF THE MIDSOUTH. SOME SLEET HAS BEEN MIXED IN AROUND THE
MEMPHIS AREA. DECIDED TO GO AHEAD AND EXPAND THE ADVISORY TO
INCLUDE MOST OF THE I-40 CORRIDOR SINCE BRIDGES AND OVERPASSES
COULD BECOME SLICK AHEAD OF THE MONDAY MORNING COMMUTE AS TEMPS
FALL BELOW FREEZING. LATEST HRRR PULLS THESE BANDS NE AND OUT OF
THE AREA BY 7 OR 8 AM. MEANWHILE RAIN HAS CLEARED OUT OF NORTH
MISSISSIPPI.
TODAY...PRECIP WILL QUICKLY EXIT THIS MORNING AND SOME TEMPORARY
CLEARING WILL OCCUR. MEANWHILE MUCH COLDER AIR WILL FILTER IN ON
BRISK NW WINDS. EXPECT COLD AIR STRATOCU TO DEVELOP AND MOVE INTO
THE AREA FROM THE NORTH AS 850 MB TEMPS DROP TO -14C AS FAR SOUTH
AS THE I-40 CORRIDOR THIS AFTERNOON. THE NAM 925 MB RH FIELDS
DEPICT THIS WELL. SOME FLURRIES ARE ALSO POSSIBLE ACROSS THE
NORTH HALF THIS AFTERNOON. TEMPS WILL BE VERY COLD WITH HIGHS
AROUND 30 NEAR THE KY/MO BORDERS TO AROUND 40 SOUTH.
TONIGHT THROUGH TUESDAY NIGHT...ARCTIC HIGH PRESSURE SETTLES OVER
THE REGION. VERY COLD TONIGHT WITH TEMPS DROPPING WELL INTO THE
TEENS. WOULD GO COLDER THAN GUIDANCE EXCEPT THERE IS SOME
GRADIENT LEFT ACROSS THE AREA WHICH WILL KEEP WINDS UP A BIT. THIS
OF COURSE WILL CAUSE WIND CHILLS TO DROPS INTO THE SINGLE DIGITS
ACROSS THE NORTH HALF BY TUESDAY MORNING. TUESDAY WILL BE VERY
COLD WITH UPPER 20S NEAR PARIS TO MID 30S SOUTH. THIS IS PUSHING
35 DEGREES BELOW NORMAL. TEMPS WILL FALL QUICKLY INTO THE 20S
TUESDAY EVENING AND THEN LEVEL OFF AS SOUTH WINDS DEVELOP AHEAD OF
AN APPROACHING SURFACE TROF.
WEDNESDAY AND WEDNESDAY NIGHT...SURFACE TROF MOVES THROUGH WITH
WARMER SW WINDS ACROSS THE AREA AND TEMPS SHOULD CLIMB INTO THE
UPPER 40S AND LOWER 50S...WHICH THOUGH PLEASANT SOUNDING IS STILL
10 DEGREES BELOW NORMAL. WEAK HIGH PRESSURE PREVAILS WEDNESDAY
NIGHT WITH WITH LOWS IN THE 20S AND 30S.
THURSDAY THROUGH THE WEEKEND...00Z MEDIUM RANGE MODELS ARE IN
MUCH BETTER AGREEMENT TODAY. A MAJOR PATTERN SHIFT WILL OCCUR AS
THE COLD UPPER TROF PUSHES EAST AND THE UPPER FLOW BECOME ZONAL BY
THE END OF THE WEEK. AN OVERRUNNING PATTERN SETS UP AS A
DISTURBANCE MOVES THROUGH IN THE ZONAL FLOW ALOFT. AS A RESULT
EXPECT RAIN CHANCES THURSDAY NIGHT AND FRIDAY. BY SATURDAY A
BROAD UPPER RIDGE WILL BUILD OVER THE AREA AS A POTENT MID LEVEL
TROF PUSHES OUT OF THE SW U.S. INTO TEXAS. AS A RESULT EXPECT
WARMER AIR TO START MOVING NORTH INTO THE MIDSOUTH WITH HIGHS IN
THE 50S AND 60S. BY SAT NIGHT AND SUNDAY THE UPPER TROF WILL PUSH
THROUGH WITH SHOWERS AND THUNDERSTORMS LIKELY.
SJM
AVIATION...
12Z TAFS
BRIEF VFR WEATHER NOW SHIFTING INTO MEM AND JBR...AND WILL FOLLOW
SUITE THIS MORNING AT MKL AND TUP. FOR THIS AFTERNOON EXPECTING A
MVFR DECK TO REFORM...WITH LIGHT SNOW FLURRIES ALSO REDVELOPING.
SECOND CLEARING OF SKY COVER WILL ARRIVE TONIGHT. NORTHWEST TO
NORTH WINDS AT 12-14KTS WITH FREQUENT GUSTS OF 18-20 KTS. WINDS
WILL DIMINISH FOR THE LATTER HALF OF THE CYCLE.
JAB
&&
.AVIATION...
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1135 AM CST MON NOV 17 2014
.AVIATION...
VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24 HOURS. LIGHT AND
VARIABLE WINDS THIS MORNING WILL COME AROUND TO THE SOUTHWEST BUT
GENERALLY REMAIN UNDER 10 KTS.
&&
.PREV DISCUSSION... /ISSUED 527 AM CST MON NOV 17 2014/
AVIATION...
VFR AND SKC WITH LIGHT WINDS THRU 18/12Z.
PREV DISCUSSION... /ISSUED 412 AM CST MON NOV 17 2014/
SHORT TERM...
DEEP AND DRY NORTHERLY FLOW OCCUPIED THE ENTIRE EXTENT OF THE
GREAT PLAINS THIS MORNING AND THIS THEME WILL REMAIN INTACT
THROUGH TONIGHT. A BROAD MERIDIONAL SURFACE RIDGE ANCHORED IN THE
LEE OF THE ROCKIES WILL SHIFT SLOWLY EAST TODAY AND BE LOCATED OFF
THE CAPROCK BY THE AFTERNOON AHEAD OF MILDER SW BREEZES. SNOWPACK
COLOR CURVE ON IR IMAGERY SHOWS THAT THE NAM AND RUC INITIALIZED
THE SNOW COVER RATHER WELL ACROSS OUR NORTHERN TWO ROWS OF
COUNTIES...SO WITH THIS IN MIND WE HAVE SCALED BACK MAX TEMPS IN
THESE AREAS AS 1 TO 3 INCHES OF SNOW WILL CERTAINLY STUNT
RADIATIONAL WARMING...ESPECIALLY AFTER SOME BITTER LOWS TO START
THE DAY. AWAY FROM THE SNOW COVER... WENT WITH THE MILD MET
NUMBERS AS THESE DRY AIRMASSES OFTEN WARM SURPRISINGLY FAST UNDER
FULL SUN WITH DOWNSLOPING WINDS. STEADY SW WINDS AREA WIDE TONIGHT
WILL MAKE FOR MILDER LOWS...HOWEVER EVEN THESE ARE STILL 10 TO 20
DEGREES BELOW CLIMO.
LONG TERM...
PROGRESSIVE PATTERN WILL DEVELOP THIS WEEK WITH A WEAK SHORTWAVE
MOVING OVER THE REGION TOMORROW. THIS WAVE WILL BRING LITTLE IN
THE WAY OF SENSIBLE WEATHER CHANGES. A BIT STRONGER SHORTWAVE WILL
MOVE OVER THE AREA DURING THE DAY THURSDAY WHICH THE MODELS HAVE
SLIGHT TIMING AND STRENGTH DIFFERENCES. AHEAD OF THIS SHORTWAVE
TROUGH...LOW LEVEL MOISTURE WILL TRY TO STREAM NORTHWARD AND SOME
BOUNDARY LAYER MOISTURE MAY MANAGE TO MAKE IT INTO THE ROLLING
PLAINS. INCREASED HIGH CLOUDS WITH THIS WAVE ALONG WITH THE
INCREASED MOISTURE MAY LIMIT THE AMOUNT OF WARMING THAT WILL TAKE
PLACE. WITH THE BEST MOISTURE RETURN TAKING PLACE EAST OF THE
FORECAST AREA...RAIN CHANCES LOOK TO STAY TOO FAR TO THE EAST OF
US TO PUT ANY MENTION IN THE FORECAST.
AS THIS WAVE PASSES BY...A WEAK COLD FRONT WILL MOVE ACROSS THE
AREA BUT ONLY DROP TEMPS BY A FEW DEGREES. A MUCH STRONGER WAVE IS
FORECAST TO MOVE OVER THE REGION DURING THE DAY SATURDAY. MODELS
ARE STILL STRUGGLING WITH HOW STRONG THIS WAVE WILL BE.
REGARDLESS...BOUNDARY LAYER MOISTURE CREEPS INTO THE ROLLING
PLAINS AND ONTO THE CAPROCK BY SATURDAY AFTERNOON. IF THE CURRENT
SOLUTIONS HOLD TRUE...WE MAY SEE SOME SHOWER/THUNDERSTORM ACTIVITY
ACROSS THE REGION. DID NOT FEEL CONFIDENT ENOUGH TO GO WITH LOW-
END CHANCE AT THIS TIME BUT DID BRING SLIGHT CHANCE POPS ACROSS
ALL BUT THE NORTHWESTERN SOUTH PLAINS.
JORDAN
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 34 14 46 24 49 / 0 0 0 0 0
TULIA 35 16 47 26 50 / 0 0 0 0 0
PLAINVIEW 37 18 48 26 51 / 0 0 0 0 0
LEVELLAND 39 20 49 27 52 / 0 0 0 0 0
LUBBOCK 40 19 48 28 52 / 0 0 0 0 0
DENVER CITY 39 21 50 27 54 / 0 0 0 0 0
BROWNFIELD 40 21 50 28 53 / 0 0 0 0 0
CHILDRESS 37 20 50 29 54 / 0 0 0 0 0
SPUR 41 22 49 31 54 / 0 0 0 0 0
ASPERMONT 42 22 51 32 57 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
33
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1119 AM CST MON NOV 17 2014
.UPDATE...UPDATE FOR 18Z AVIATION BELOW.
&&
.AVIATION...VFR CONDITIONS THROUGH THE TAF PERIOD. CLEAR SKIES
TODAY WITH HIGH CIRRUS POSSIBLE OVERNIGHT. N WINDS 10-15 KTS
THROUGH THE AFTERNOON...OCCASIONAL GUSTS TO AROUND 20 KTS
ALONG AND EAST OF I-35. WINDS DECREASING TO 5-10 KTS 22Z-00Z THEN
BECOMING LGT/VRB OVERNIGHT.
&&
.PREV DISCUSSION... /ISSUED 943 AM CST MON NOV 17 2014/
UPDATE...
TO REMOVE FREEZE WARNING.
DISCUSSION...
TEMPERATURES HAVE WARMED BACK ABOVE FREEZING AND THE FREEZE
WARNING HAS EXPIRED. SENDING NEW ZONES TO REMOVE THE FREEZE
WARNING HEADLINE.
PREV DISCUSSION... /ISSUED 534 AM CST MON NOV 17 2014/
AVIATION... /12Z TAF UPDATE/
MVFR CIGS CLEARED RAPIDLY OVER THE PAST SEVERAL HOURS...AND VFR
SKIES ARE FORECAST FOR THE REST OF THE TAF PERIODS. SOME STRONG
LOW LEVEL NORTHERLIES WILL ADD SOME GUST POTENTIAL FOR DRT THROUGH
16Z AND FOR THE I-35 TERMINAL SITES THROUGH 20Z. THE HIGHER GUSTS
SHOULD BE GENERALLY AROUND 25 KNOTS. LIGHT WINDS ARE FORECAST BY
THIS EVENING.
PREV DISCUSSION... /ISSUED 422 AM CST MON NOV 17 2014/
SHORT TERM (TODAY THROUGH TUESDAY)...
EARLY MORNING OBSERVATIONS REVEAL A STEADY FALL IN TEMPERATURES AS
COLD AIR POURS INTO THE REGION AND LOW CLOUDS DECREASE. BASED ON
THE LATEST OBSERVATIONS AND THE HRRR GUIDANCE...WE HAVE OPTED FOR
A FREEZE WARNING FOR COUNTIES ALONG AND NEAR THE U.S. HIGHWAY 90
CORRIDOR. WELL BELOW NORMAL HIGH TEMPERATURES ARE EXPECTED ACROSS
ALL OF SOUTH CENTRAL TEXAS TODAY AS SURFACE HIGH PRESSURE BUILDS.
HIGHS WILL RANGE FROM THE UPPER 40S IN THE HILL COUNTRY TO THE
LOWER 50S ALONG THE RIO GRANDE. WE EXPECT GUSTY NORTH WINDS TO
CONTINUE THROUGH MID-AFTERNOON. WINDS WILL THEN DECREASE QUICKLY
BY SUNSET AS THE PRESSURE GRADIENT RELAXES. TEMPERATURES WILL FALL
BELOW FREEZING ACROSS THE VAST MAJORITY OF SOUTH CENTRAL TEXAS
TONIGHT. LOWS IN THE 20S ARE EXPECTED FOR MOST AREAS TONIGHT. THE
EXCEPTION WILL BE ALONG THE SOUTHERN RIO GRANDE PLAINS...WHERE
LOWS MAY REMAIN CLOSER TO FREEZING. BELOW NORMAL HIGH TEMPERATURES
ARE EXPECTED AGAIN ON TUESDAY WITH HIGHS IN THE 50S.
LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...
A WARMING TREND IS EXPECTED THROUGH THE REMAINDER OF THE WORK WEEK
AND UPCOMING WEEKEND AS SOUTHERLY FLOW IN THE LOW-LEVELS REMAINS
INTACT. THERE IS SOME INDICATION IN THE MODELS WE COULD SEE A WEAK
COLD FRONT MOVE INTO THE HILL COUNTRY ON FRIDAY. THIS FEATURE IS
RATHER WEAK AND WOULD LIKELY NOT HAVE A SIGNIFICANT IMPACT ON
TEMPERATURES. DRY WEATHER IS EXPECTED ON WEDNESDAY...WITH RAIN
CHANCES RETURNING TO THE FORECAST ON THURSDAY FOR AREAS EAST OF
I-35. RAIN CHANCES EXPAND WESTWARD FRIDAY AND SATURDAY AS AN UPPER
LEVEL TROUGH APPROACHES FROM THE WEST. THIS UPPER LEVEL TROUGH
WILL AID IN SENDING A PACIFIC COLD FRONT INTO THE REGION LATE
SATURDAY INTO SUNDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 50 27 53 36 61 / 0 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 51 23 53 32 60 / 0 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 53 27 54 35 61 / 0 0 0 0 0
BURNET MUNI AIRPORT 48 25 52 32 61 / 0 0 0 0 0
DEL RIO INTL AIRPORT 53 30 53 35 59 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 49 22 52 33 60 / 0 0 0 0 0
HONDO MUNI AIRPORT 52 24 52 34 55 / 0 0 0 0 0
SAN MARCOS MUNI AIRPORT 52 26 53 33 59 / 0 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 50 27 52 34 60 / 0 0 - 0 10
SAN ANTONIO INTL AIRPORT 53 27 53 38 60 / 0 0 0 0 0
STINSON MUNI AIRPORT 53 30 54 37 59 / 0 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...05
SYNOPTIC/GRIDS...76
PUBLIC SERVICE/DATA COLLECTION...12
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1238 PM EST MON NOV 17 2014
.SYNOPSIS...
A STRONG COLD FRONT SWINGS ACROSS THE AREA TODAY. ARCTIC AIR WILL
FOLLOW TONIGHT WITH HIGH PRESSURE MOVING INTO THE MID MISSISSIPPI
VALLEY. EXPECT A PERIOD OF SNOW SHOWERS...WINDS AND COLD WIND
CHILLS LATE TONIGHT INTO TUESDAY MORNING AS A RESULT.
HIGH PRESSURE BUILDS ACROSS THE SOUTHEAST INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1040 AM EST MONDAY...
BASED ON LATEST SURFACE OBSERVATIONS... THE COLD FRONT APPEARS TO
BE MOVING A COUPLE HOURS AHEAD OF THE PREVIOUS FORECAST. THIS IS
REFLECTED IN THE FORECAST WITH REDUCED TEMPERATURES AND EARLIER
ONSET OF SNOW IN THE WESTERN SLOPES. SNOW IS NOW FORECAST TO BEGIN
AROUND 3PM FOR WESTERN GREENBRIER COUNTRY.
PREVIOUS DISCUSSION...
EARLIER RUN OF THE HRRR HAD A GREAT HANDLE ON THE RAIN MOVING IN
FROM THE SOUTHWEST. FOLLOWED ITS SOLUTION THROUGH THE
MORNING...BLENDING IN THE 00Z GFS/NAM. LOOKS LIKE A SLAM DUNK FOR
EVERYONE SEEING RAIN TODAY...THOUGH AMOUNTS MAY BE LESS THAN EARLIER
THOUGHT AS DID NOT SEE AS MUCH FALL SUNDAY.
STILL A GOOD ONE HALF TO THREE QUARTERS OF AN INCH WILL OCCUR TODAY.
THIS FRONT LOCATED ACROSS THE CENTRAL APPALACHIANS SOUTHWEST INTO
ALABAMA WILL SLIDE EAST ACROSS THE AREA TODAY...WITH A COUPLE WAVES
OF LOW PRESSURE ALONG IT. THE MAIN FORECAST ISSUE WILL BE THE COLDER
AIR ARRIVING BEHIND THE FRONT. THE 00Z NAM DEPICTED THE COLDER AIR
BETTER AT 06Z AT 8H THAN THE GFS/ECMWF...SO LEANED TOWARD IT TEMP
FORECAST. SHOULD SEE DEEP MOISTURE EDGE EAST EARLY THIS AFTERNOON IN
THE MTNS WHILE THE COLDER AIR STARTS TURNING RESIDUAL SHOWERS OVER
TO SNOW LATER IN THE AFTERNOON. BY DUSK MOST OF THE EASTERN HALF OF
THE CWA WILL BE DRYING OUT AS WINDS TURN WNW. TEMPS DESPITE THE
RAIN...OR REALLY AS A RESULT OF THE RAIN BRINGING DOWN THE WARMER
TEMPS ALOFT MAY BRING READINGS INTO THE 50S BEFORE THE COLD AIR
ARRIVES IN THE PIEDMONT THIS AFTERNOON. IN THE MTNS HIGHS SHOULD BE
OCCURRING BY MIDDAY THEN DROPPING IN THE LATE AFTERNOON.
FORECAST SOUNDINGS IN THE MTNS SHOW MOISTURE BECOMING SHALLOW
FAST...WITH THE FAVORABLE SNOW GROWTH TEMPS ALOFT NOT BEING REALIZED
UNTIL LATE EVENING...SO COULD BE SOME PATCHY FREEZING DRIZZLE
ISSUES...AND WILL ADVERTISE THIS IN THE MTNS OF THE FAR WEST THIS
EVENING. THIS HERE LIES THE PROBLEM...WHERE IT RAINS...COMBINED WITH
ARCTIC AIR ARRIVING AND SNIZZLE(SNOW AND FREEZING DRIZZLE)
FOLLOWING...ROADS WILL BECOME SLICK IN THE HIGHER ELEVATIONS BY LATE
DUSK. AFTER COLLABORATING WITH NEIGHBORING OFFICES...IT WAS DECIDED
TO GO WITH A WINTER WX ADVISORY FOR THE NC MTNS INTO THE GRAYSON
HIGHLANDS...BUT TO DELAY ANY HEADLINES...IF THEY ARE NEEDED FURTHER
NORTH INTO THE MTN EMPIRE OF SW VA AND SE WV MTNS. STILL THINK THE
TEMPS FALLING FAST LATE TONIGHT MAY REQUIRE AT LEAST A SPECIAL WX
STATEMENT. THE SNOWFALL ACCUMULATION WILL BE LIGHT GIVEN THE LIMITED
MOISTURE BUT 1 TO 3 INCHES IN THE WESTERN SLOPES ARE POSSIBLE INTO
TUESDAY MORNING.
IN ADDITION...THE WINDS WILL BE GUSTING OVER 40 MPH WITH 6 HR
PRESSURE RISES OF 5-7MB EXPECTED BEHIND THE FRONT THIS EVENING INTO
TUESDAY MORNING. THIS WAS ADDED TO THE WINTER WX ADVISORY IN THE NC
MTNS. CLOUDS MAY PREVENT IDEAL MIXING OF THE STRONGER WINDS
ALOFT...BUT WHERE IT THE CLOUD/CLEARING LINE IS ALONG/NEAR THE BLUE
RIDGE...THINK AN OCCASIONAL 50 MPH GUST WILL BE REALIZED. OUTSIDE
THE WINTER WX ADVISORY FOR ELEVATIONS ABOVE 3000 FT...HIGHLIGHT
WEATHER IN THE HAZARDOUS WEATHER OUTLOOK. WILL TAKE A LOOK AT MORE
DATA COMING IN AND FURTHER COORDINATING WITH OTHER WFO OFFICES TO
SEE IF MORE HEADLINES ARE NEEDED.
FOR TONIGHT...TEMPS WILL DROP INTO THE TEENS MOUNTAINS...SOME SINGLE
DIGITS HIGHEST ELEVATIONS...WITH 20S IN THE EAST. WIND CHILLS BY
DAWN TUESDAY WILL RANGE FROM 5 ABOVE TO 5 BELOW IN THE
MOUNTAINS...TO THE TEENS IN THE EAST.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 315 AM EST MONDAY...
COLD FRONT PUSHES OUT INTO THE ATLANTIC OCEAN TUESDAY AS THE 1033
SURFACE HIGH PRESSURE IN TEXAS BUILDS NORTHWARD INTO OUR REGION. THE
AXIS OF THE UPPER TROF CROSS OUR AREA TUESDAY INTO TUESDAY NIGHT.
GUSTY NORTHWEST WINDS WILL CONTINUE TUESDAY AS A TIGHT PRESSURE
GRADIENT WILL REMAIN OVER THE REGION THROUGH TUESDAY. THE GFS...NAM
AND HIRESW-ARW SHOWED UPSLOPE SNOW SHOWERS AND SNOW FLURRIES
CONTINUE IN THE WESTERN MOUNTAINS. ADDITIONAL LIGHT ACCUMULATIONS
MAY BE POSSIBLE IN THE NORTHWEST UPSLOPE FAVORED LOCATIONS. HIGH
TEMPERATURES TUESDAY WILL RANGE FROM THE UPPER TEENS IN THE
NORTHWEST MOUNTAINS TO THE MID 30S IN THE PIEDMONT. HIGH PRESSURE
CONTINUES TRAVEL EASTWARD TUESDAY NIGHT. TUESDAY NIGHT WILL BE A
VERY COLD NIGHT WITH TEMPERATURES ACROSS THE AREA RANGING FROM THE
SINGLE DIGITS IN THE HIGHER ELEVATIONS TO THE UPPER TEENS ACROSS THE
PIEDMONT. WINDS WILL DECREASE TUESDAY NIGHT...BUT WIND CHILLS WILL
BE COLD WITH SINGLE DIGITS IN THE WEST TO TEENS IN THE EAST.
A WARM FRONT WILL PASS OVER THE REGION WEDNESDAY...AS A COLD FRONT
DROPS SOUTH INTO THE OHIO VALLEY. WEDNESDAY AFTERNOON HIGH
TEMPERATURES WILL AVERAGE 20F COLDER THAN NORMAL WITH READINGS FROM
THE LOWER 30S IN THE MOUNTAINS TO THE LOWER 40S IN THE PIEDMONT.
COLD FRONT APPROACHES FROM THE WEST WEDNESDAY NIGHT. ALLOWED FOR
ISOLATED SNOW SHOWERS ACROSS THE NORTH. LOW TEMPERATURES WEDNESDAY
NIGHT WILL GENERALLY BE FROM AROUND 20 DEGREES TO THE MID 20S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 400 PM EST SUNDAY...
SURGE OF ARCTIC AIR TO INVADE THE REGION INTO THURSDAY. THIS WAS NOT
ADVERTISED A FEW RUNS BACK...BUT GIVEN GENERAL CONSENSUS AMONG THE
MODELS AND A PREVAILING MEAN DEEP MERIDIONAL TROUGH ACROSS THE
EASTERN HALF OF THE U.S...THIS APPEARS TO BE A REASONABLE SOLUTION
AND THUS WILL LEAN IN THIS DIRECTION. HOWEVER...IN TERMS OF
INTENSITY...THIS FINAL ARCTIC SURGE WILL NOT EVEN COME CLOSE TO THE
ONE EARLIER IN THE WEEK. MOISTURE IS LIMITED...BUT SLIGHT CHC TO LOW
CHC POPS FOR UPSLOPE -SHSN ACROSS THE USUAL WESTERN UPSLOPE AREAS OF
THE ALLEGHANYS SEEMS REASONABLE AND HAVE BEEN INCLUDED...WITH NO
MENTION OF POPS EAST OF THE ALLEGHANY FRONT. THE PARENT ARCTIC HIGH
WILL SETTLE OVER THE REGION EARLY SATURDAY...SO BELOW NORMAL
TEMPERATURES SHOULD REMAIN IN PLACE THROUGH SAT MORNING. MODEL TEMPS
IN REASONABLE AGREEMENT THROUGH FRI...BUT FEEL THE GFS MOS IS TOO
QUICK TO SPREAD WARMER RETURN FLOW INTO THE REGION SAT...SO LEANED
TOWARD THE COLDER ECMWF MOS.
BIGGER QUESTIONS REMAIN FOR THE REMAINDER OF THE EXTENDED PERIODS.
AS THE ARCTIC HIGH RETREATS TOWARD THE COAST SAT...THE LONG
AWAITED RETURN TO A LESS AMPLIFIED FLOW PATTERN BEGINS TO EVOLVE.
THE EASTERN U.S. TROUGH IS REPLACED BY A SHORT WAVE RIDGE AS BROAD
MEAN TROUGHING RELOCATES TO THE WESTERN/CENTRAL U.S. THE MAIN
CONCERN FOR THE WEEKEND IS THE TIMING AND ASSOCIATED
WARMING/MOISTENING WITH A STRONG NEGATIVELY TITLED HIGHLY
PROGRESSIVE SHORT WAVE PROGGED TO EJECT OUT OF THE BASE OF THE
MEAN TROUGH INTO THE SOUTHEAST STATES SAT NIGHT-SUN. 12Z ECMWF IN
EXCELLENT AGREEMENT WITH 12Z GFS IN BRINGING THIS SYSTEM THROUGH
OUR REGION SUN AFTERNOON. SUPERBLEND POPS WERE LIKELY TO
CATEGORICAL SUN NIGHT-MON. GIVEN THE ASSOCIATED PVA...AND AMOUNT
OF MOIST/WARM ADVECTION INTO THE REGION...THIS SEEMED REASONABLE.
HOWEVER...NEIGHBORING OFFICES WERE NOT ON BOARD WITH THESE HIGH
VALUES THIS FAR OUT...SO STOPPED AT A MORE REASONABLE 50 PERCENT
VALUE FOR NOW. GIVEN RECENT MODEL RUN-TO-RUN VARIATION...THAT
SEEMED REASONABLE FOR SURE. A SIGNIFICANT WARM UP WILL ENSUE SAT-
SUN...BUT AS NOTED ABOVE...PERHAPS NOT TO THE DEGREE ADVERTISED BY
THE MEX MOS. THUS...HAVE USED A MODEL BLEND FOR SAT- SUN.
AN EVEN MORE SIGNIFICANT NEGATIVELY TILTED UPPER TROUGH APPEARS ON
TRACK FOR THE REGION INTO MON. ECMWF/GFS SHOWING SOME INCREDIBLY
WARM/MOIST AIR FOR THIS TIME OF YEAR SPREADING INTO THE REGION
FROM THE SOUTH BY MON MORNING ON THE HEELS A STRONG LOW-LEVEL SOUTHERLY
JET WITH DEWPOINTS APPROACHING 60 DEGREES BY MON AFTERNOON ACROSS
THE PIEDMONT AND SOUTHSIDE. PROGGED LIFTED INDICES AND CAPES ALONG
WITH EVIDENT SHEAR SUGGEST SOME -TSRA MAY NEED TO BE CONSIDERED BY
MON AFTERNOON ACROSS THE PIEDMONT. TO SAY THE LEAST...EARLY NEXT
WEEK WILL BE IN SHARP CONTRAST TO THE WEATHER EXPECTED THIS WEEK
WITH TEMPERATURES ACTUALLY ABOVE SEASONAL NORMALS...ESPECIALLY IF
LOWS ARE ONLY IN THE 50S MON MORNING WITH HIGHS IN THE 60S.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 640 AM EST MONDAY...
HEAVY RAIN AXIS SHIFTS EAST EARLY THIS AFTERNOON. THE COLD
FRONT/WIND SHIFT IS EXPECTED ACROSS WESTERN SLOPES (BLF/LWB) BY
19Z...ALONG THE BLUE RIDGE (BCB/ROA) AROUND 20Z-22Z...AND THE
PIEDMONT (LYH/DAN) BY 00Z THIS EVENING. VISIBILITIES/CEILINGS WILL
IMPROVE SOME THROUGH THE DAY AND CONTINUE TO IMPROVE FOR AREAS
EAST OF THE BLUE RIDGE (ROA/LYH/DAN). ACROSS THE MOUNTAINS MVFR
VISIBILITIES/CEILING FOR MOST AREAS...WESTERN SLOPES IFR WITH
SNOW THROUGH EARLY MORNING.
PRESSURE RISES BEHIND THE FRONT WILL BRING WINDY/GUSTY CONDITIONS
TO THE AREA. STRONGER WINDS WILL BE OVER THE MOUNTAINS THROUGH
TONIGHT...THEN AS INVERSION LOWERS ALL SITES WILL HAVE GUSTY
CONDITIONS THROUGH THE DAY TUESDAY.
ARCTIC BLAST OF AIR MAY LEAD TO WATER FREEZING ON
RUNWAYS/AIRPLANES THIS EVENING...THOUGH WINDS MAY LEAD TO QUICKER
EVAPORATION OF THE WET SFCS.
EXTENDED DISCUSSION...
EXPECT MAINLY VFR WEATHER TUESDAY NIGHT-THURSDAY. NEXT SYSTEM
APPEARS TO ARRIVE FRIDAY WITH MVFR CIGS IN THE MTNS.
&&
.CLIMATE...
AS OF 315 PM EST SUNDAY...
RECORD COOLEST HIGHS...TUESDAY NOV 18TH
BLACKSBURG VA...30 IN 2008
BLUEFIELD WV....27 IN 2008
DANVILLE VA.....38 IN 1959
ROANOKE VA......33 IN 1951
LEWISBURG WV....30 IN 2008
LYNCHBURG VA....32 IN 1924
&&
.EQUIPMENT...
AS OF 120 AM EST MONDAY...
KFCX RADAR DOWN DUE TO TRANSMITTER FAULT. TECHNICIANS WILL WORK ON
RESTORING THIS BY NOON TODAY.
THE VISIBILITY SENSOR AT KLYH...LYNCHBURG AIRPORT...WILL BE OUT
OF SERVICE UNTIL MONDAY WHEN TECHNICIANS WILL REPLACE THE SENSOR.
UNTIL THEN THE VISIBILITY WILL ONLY BE REPORTED WHEN THE CONTROL
TOWER IS STAFFED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EST
TUESDAY FOR VAZ015.
NC...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EST
TUESDAY FOR NCZ001-018.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...RCS/WP
SHORT TERM...KK
LONG TERM...RAB
AVIATION...RCS/WP
CLIMATE...RCS
EQUIPMENT...WERT/WP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
252 PM CST MON NOV 17 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 143 PM CST MON NOV 17 2014
CHALLENGES INCLUDE LINGERING LIGHT SNOW SHOWERS/FLURRIES AND
BLOWING SNOW THIS EVENING...FOLLOWED BY LIGHT ACCUMULATING SNOW
TUESDAY NIGHT INTO WEDNESDAY MORNING AND THEN UNSEASONABLE COLD
CONTINUING THROUGH FRIDAY. 17.12Z GLOBAL MODELS ARE IN GOOD
AGREEMENT THROUGH 22.00Z (FRIDAY NIGHT)...DIVERGING INTO THE
WEEKEND WITH THE TRACK AND EVOLUTION OF A STRONG EAST-PACIFIC
WAVE AS IT EJECTS FROM THE SOUTHERN PLAINS INTO THE UPPER
MIDWEST.
FOR TONIGHT...LIGHT SNOW SHOWERS/FLURRIES IN COLD CYCLONIC FLOW
ALOFT WILL DISSIPATE BY MIDNIGHT WITH NO MORE THAN A COUPLE TENTHS
OF ACCUMULATION. BLOWING/DRIFTING SNOW ALSO EXPECTED TO SUBSIDE
AFTER SUNSET. WITH ARCTIC AIR MASS FULLY IN PLACE AND AFTERNOON
HIGHS TODAY ONLY REACHING THE MID TEENS...EXPECT LOWS TO EASILY
DROP INTO THE SINGLE DIGITS ABOVE ZERO AND EVEN FAVORED COLD SPOTS
A FEW DEGREES BELOW ZERO. 17.18Z RAP SHOWS 0.5 KM WINDS OVERNIGHT
AROUND 30 KTS WITH A NEARLY DRY ADIABATIC BOUNDARY LAYER TO THIS
LEVEL...SO EXPECT A BREEZY NIGHT WITH WESTERLY WINDS FROM 10 TO 15
MPH. THIS WILL RESULT IN WIND CHILL VALUES BY TUESDAY MORNING FROM
10 TO 20 BELOW ZERO. THE REST OF TUESDAY WILL BE MOSTLY CLOUDY BUT
DRY AND BREEZY WITH AFTERNOON HIGHS SIMILAR TO TODAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 143 PM CST MON NOV 17 2014
THE NEXT SHORT-WAVE ALOFT ROTATES THROUGH THE UPPER MISSISSIPPI
RIVER VALLEY TUESDAY NIGHT. 850 TO 600 HPA FORCING INCREASES
ALONG WARM FRONTAL BOUNDARY AND WITH AROUND 4 UBAR/S OF OMEGA
CENTERED ALONG THE DENDRITIC GROWTH ZONE...EXPECT A QUICK ONE INCH
OR LESS OF ACCUMULATION MAINLY ALONG AND EAST OF THE MISSISSIPPI
RIVER. INCREASED POPS INTO THE LIKELY CATEGORY TUESDAY NIGHT FOR
THESE AREAS. TEMPERATURES TUESDAY NIGHT WILL DROP INTO THE SINGLE
DIGITS TO LOW TEENS ABOVE ZERO.
REINFORCING COLD FRONT SWINGS ACROSS THE REGION EARLY WEDNESDAY
MORNING...KEEPING DAILY TEMPERATURES WELL BELOW SEASONAL NORMALS
THROUGH THE REST OF THE WORK WEEK. EXPECT HIGHS IN THE TEENS AND
20S AND LOWS IN THE SINGLE DIGITS AND LOW TEENS. WEDNESDAY THROUGH
FRIDAY WILL BE DRY...HOWEVER...WITH SURFACE HIGH PRESSURE MOVING
ACROSS THE NATION/S MID-SECTION. BREEZY WEST-NORTHWEST WINDS
WEDNESDAY AND THURSDAY WILL BECOME LIGHT THURSDAY NIGHT INTO
FRIDAY AS CENTER OF SURFACE HIGH SLIDES ACROSS IOWA AND PRESSURE
GRADIENT WEAKENS.
SATURDAY THROUGH MONDAY...17.12Z GFS/ECMWF IN AGREEMENT THAT AN
OPEN WAVE WILL MOVE INTO THE UPPER MIDWEST FROM THE SOUTHERN
PLAINS. GFS IS QUICKER AND FARTHER EAST WITH SURFACE LOW TRACK
COMPARED TO THE ECMWF AND THUS LESS ROBUST WITH PRECIP ACROSS THE
FORECAST AREA. THE ECMWF...HOWEVER...DEPICTS 0.75 TO 1.5 INCHES OF
LIQUID PRECIP THROUGH MONDAY AS IT DRAGS A SLOW-MOVING DEFORMATION
PRECIP ZONE ACROSS THE AREA. BOTH MODELS WARM ENOUGH FOR ANY
PRECIP TO INITIALLY FALL AS RAIN ON SATURDAY/SUNDAY AND EVENTUALLY
CHANGING OVER TO SNOW SUNDAY NIGHT INTO MONDAY. CONFIDENCE HIGH
ENOUGH TO INCREASE POPS INTO THE HIGH CHANCE CATEGORY...BUT STILL
LOTS OF DETAILS TO SORT OUT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1146 AM CST MON NOV 17 2014
STRONG/COLD CYCLONIC FLOW CONTINUES OVER THE AREA IN THE WAKE OF
ARCTIC COLD FRONTAL PASSAGE. NOTICED KRST HAS SLIPPED DOWN TO 4SM
THIS PAST HOUR. CALL TO THE TOWER INDICATED THAT SNOW WAS MAINLY
DRIFTING RIGHT NOW...BUT WITH STRONGER GUSTS THIS AFTERNOON...
SHOULD SEE SOME MORE BLSN DOWN TO 1SM AT TIMES. KLSE..BEING A BIT
MORE SHELTERED SHOULD JUST SEE SOME LOCALIZED DRIFTING OF SNOW.
OTHERWISE...COLD CYCLONIC FLOW WAS ALSO PRODUCING MVFR CLOUD COVER
WITH SNOW SHOWERS. EXPECTING MVFR CLOUD CONDITIONS WITH FLURRIES
TO CONTINUE RIGHT THROUGH TONIGHT INTO TUESDAY MORNING. PLAN ON
GUSTINESS OF THE WINDS TO SUBSIDE GOING INTO THIS EVENING WITH
LOSS OF MIXING THROUGH THE BOUNDARY LAYER.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ086-
087-094-095.
IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ008-
009-018-019.
&&
$$
SHORT TERM...ROGERS
LONG TERM...ROGERS
AVIATION...DAS