Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/04/15
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1013 AM MST FRI JAN 2 2015
.UPDATE...
ISSUED AT 1013 AM MST FRI JAN 2 2015
CLOUD DECK ALONG AND NORTH OF I-70/I-76 IS STILL INTACT...AND
RADAR/OBS POINT TO JUST A FEW FLURRIES IN NORTHERN WELD COUNTY.
CLOUD DECK IS SHOWING SLOW SIGNS OF BREAKING AND WITH FLOW ALOFT
FINALLY TURNING MORE WESTERLY THIS AFTERNOON IT SHOULD BE ABLE TO
PULL OFF THE FRONT RANGE AND ERODE. HAVE ADJUSTED LATEST FORECAST
THIS WAY FOR MORE CLOUDS INTO EARLY AFTERNOON THEN SOME CLEARING.
ATTENTION WILL THEN TURN TOWARD TOMORROWS COLD FRONT. SNOW
EXPECTED TO DEVELOP SHORTLY BEHIND THE FRONT WITH BLOWING SNOW
LIKELY BEING A PROBLEM AS WINDS INCREASE. WILL ANALYZE FULL SUITE
OF 12Z GUIDANCE BEFORE ISSUING APPROPRIATE HIGHLIGHTS.
UPDATE ISSUED AT 734 AM MST FRI JAN 2 2015
CLOUD BAND NORTH OF I-70 IS BARELY MOVING AT THIS POINT SO ADDED
MORE CLOUDS TO THE MORNING FORECAST ESPECIALLY OVER THE NORTHERN
HALF OF THE FORECAST AREA. THERE SHOULD BE BREAKAGE BY MID DAY PER
LATEST RAP OUTPUT...BUT COULD LINGER OVER THE NORTHEAST CORNER
INTO THE AFTERNOON. ALSO ADDED A FEW SNOW SHOWERS NEAR THE WYOMING
BORDER PER LATEST OBS AND RADAR RETURNS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 400 AM MST FRI JAN 2 2015
AN UPPER LOW JUST SOUTH OF THE FOUR CORNERS AND A SECONDARY UPPER
LOW OVER NORTHEAST COLORADO ARE CONNECTED BY AN ELONGATED UPPER
TROUGH. LOW CLOUDS AND POCKETS OF LIGHT SNOWFALL ACROSS NORTHERN
SECTIONS OF THE CWA COINCIDE WITH A +70KT JET MAXIMA ROUNDING THE
NORTHWEST SIDE OF THE UPPER LOW OVER NERN COLORADO. LOW IS EVIDENT
ON IR AND H20 VAPOR SATL IMAGERY. MODELS SHOW THIS NORTHERN LOW
AND ITS ACCOMPANYING CLOUD BAND AND LIGHT PRECIP TRACKING
NORTHEAST AWAY FROM THE FRONT RANGE AND ACROSS NEBRASKA THIS
MORNING. ONCE OUT OF THE AREA...SHOULD SEE CLEARING MOST AREAS AS
DRIER SLIGHTLY WARMER AIR ALOFT ADVECTS IN FROM THE NORTHWEST.
EXPECT HIGHS TODAY TO BE 8-12F WARMER THAN YESTERDAY.
TONIGHT...AFTER CLEAR SKIES AND LIGHT BREEZES IN THE
EVENING...MID AND HIGH CLOUDS ARE EXPECTED TO ENCROACH UPON THE
NRN MTN RANGES AFTER MIDNIGHT IN ADVANCE OF A CLIPPER WEATHER
SYSTEM RACING DOWN FROM BRITISH COLUMBIA. COULD POSSIBLY SEE A
LIGHT SNOW SHOWERS REACHING THE PARK AND GORE RANGES BEFORE
MORNING. IN ADDITION...STRENGTHENING NORTHWEST FLOW ALOFT WILL
CAUSE WLY WINDS TO INCREASE IN SPEED ON MTN RIDGES AND UPPER EAST
SLOPES OF THE FRONT RANGE AFTER MIDNIGHT. IN THESE AREAS COULD
SEE GUSTS IN THE 40-50 MPH RANGE. OTHERWISE IT WILL REMAIN DRY AT
LOWER ELEVATIONS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 400 AM MST FRI JAN 2 2015
MAIN CONCERN WILL BE IMPACT FROM THE UPPER LEVEL TROF WHICH WILL
MOVE RAPIDLY FROM THE NORTHERN ROCKIES AND THROUGH COLORADO ON
SATURDAY. ASSOCIATED COLD FRONT WILL MOVE SOUTHWARD OVER THE
PLAINS MIDDAY ON SATURDAY WITH INCREASING NORTHERLY UPSLOPE FLOW
AND MOISTURE DURING THE AFTERNOON. MODEST QG UPWARD FORCING/JET
DYNAMICS AND RATHER STEEP LAPSE RATES WILL RESULT IN A WINDOW OF
SNOW SATURDAY AFTERNOON AND EVENING OVER MUCH OF CWA. GIVEN THE
STEEPENING LAPSE RATES AND INFLUX OF COLDER AIR...COULD SEE A FEW
HOURS OF MODERATE TO HEAVY SNOW OVER PORTIONS OF THE PLAINS.
LATEST GFS/NAM SHOWING 1-4 INCHES OF SNOW WHILE EUROPEAN A BIT
LESS WITH 1-2 INCHES. WITH MORE MODEL CONSISTENCY IN THE RUN TO
RUNS SHOWING UP IN THE PAST FEW DAYS...WILL BOOST POPS UP TO
LIKELY FOR MUCH OF THE AREA.
BEHIND THE DISTURBANCE...THE FLOW WILL INCREASE FROM THE
NORTHWEST WITH SOME DEVELOPMENT OF DOWNSLOPE WINDS OVER THE
MOUNTAINS AND EAST SLOPES FROM SUNDAY THROUGH TUESDAY. GUSTS IN
THE 50-70 MPH RANGE IS POSSIBLE SO WILL HAVE TO WATCH FOR
POTENTIAL FOR HIGH WINDS IN THESE PERIODS. WITH THE DOWNSLOPE
WINDS...TEMPERATURES WILL WARM TO SEASONAL NORMALS ACROSS LOWER
ELEVATIONS. LATEST LONG RANGE MODELS ARE NOW SHOWING ANOTHER
INFLUX OF COLDER AIR AND CHANCE OF PRECIP LATE TUESDAY AFTERNOON
AND NIGHT. WILL ADD SOME LOW POPS OVER THE FAR NORTHEAST CORNER IN
PROXIMITY TO THE UPPER JET. WITH THIS FLOW PATTERN...THE NORTHERN
MOUNTAINS WILL BE SUSCEPTIBLE TO A CHANCE OF LIGHT SNOW THROUGH
TUESDAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z SATURDAY MORNING)
ISSUED AT 1013 AM MST FRI JAN 2 2015
SCATTERED CLOUDS AROUND 5000-7000 FT AGL AND A SCT-BKN HIGHER
DECK AROUND 10000-12000 FEET WILL DECREASE 21Z-00Z. SOUTH/
SOUTHWEST WINDS AROUND 12 KNOTS AT KDEN WILL DECREASE THROUGH 20Z
AND TRY TO TRANSITION MORE SOUTHEASTERLY. WINDS AT KDEN...KAPA AND
KBJC ARE EXPECTED TO RETURN TO A SOUTH-SOUTHWEST DIRECTION AT
6-12KTS BY 00Z-02Z AND REMAIN THERE OVERNIGHT UNDER CLEAR TO
MOSTLY CLEAR SKIES.
ATTENTION THEN TURNS TOWARD COLD FRONT EXPECTED TO REACH THE AREA
SATURDAY. MOST LIKELY TIME OF FROP IS FROM 16Z-18Z WITH 15-20G25-30KT
NORTH WINDS. SNOW WILL ALSO DEVELOP A FEW HOURS BEHIND THE FRONT
WITH IFR CEILINGS AND VISIBILITIES LIKELY SATURDAY AFTERNOON.
BLOWING SNOW MAY FURTHER REDUCE VISIBILITIES ESPECIALLY AT KDEN
AND KAPA WHERE STRONGER WINDS AND MORE FRESH SNOW COVER EXISTS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...BAKER
LONG TERM...ENTREKIN
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
734 AM MST FRI JAN 2 2015
.UPDATE...
ISSUED AT 734 AM MST FRI JAN 2 2015
CLOUD BAND NORTH OF I-70 IS BARELY MOVING AT THIS POINT SO ADDED
MORE CLOUDS TO THE MORNING FORECAST ESPECIALLY OVER THE NORTHERN
HALF OF THE FORECAST AREA. THERE SHOULD BE BREAKAGE BY MID DAY PER
LATEST RAP OUTPUT...BUT COULD LINGER OVER THE NORTHEAST CORNER
INTO THE AFTERNOON. ALSO ADDED A FEW SNOW SHOWERS NEAR THE WYOMING
BORDER PER LATEST OBS AND RADAR RETURNS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 400 AM MST FRI JAN 2 2015
AN UPPER LOW JUST SOUTH OF THE FOUR CORNERS AND A SECONDARY UPPER
LOW OVER NORTHEAST COLORADO ARE CONNECTED BY AN ELONGATED UPPER
TROUGH. LOW CLOUDS AND POCKETS OF LIGHT SNOWFALL ACROSS NORTHERN
SECTIONS OF THE CWA COINCIDE WITH A +70KT JET MAXIMA ROUNDING THE
NORTHWEST SIDE OF THE UPPER LOW OVER NERN COLORADO. LOW IS EVIDENT
ON IR AND H20 VAPOR SATL IMAGERY. MODELS SHOW THIS NORTHERN LOW
AND ITS ACCOMPANYING CLOUD BAND AND LIGHT PRECIP TRACKING
NORTHEAST AWAY FROM THE FRONT RANGE AND ACROSS NEBRASKA THIS
MORNING. ONCE OUT OF THE AREA...SHOULD SEE CLEARING MOST AREAS AS
DRIER SLIGHTLY WARMER AIR ALOFT ADVECTS IN FROM THE NORTHWEST.
EXPECT HIGHS TODAY TO BE 8-12F WARMER THAN YESTERDAY.
TONIGHT...AFTER CLEAR SKIES AND LIGHT BREEZES IN THE
EVENING...MID AND HIGH CLOUDS ARE EXPECTED TO ENCROACH UPON THE
NRN MTN RANGES AFTER MIDNIGHT IN ADVANCE OF A CLIPPER WEATHER
SYSTEM RACING DOWN FROM BRITISH COLUMBIA. COULD POSSIBLY SEE A
LIGHT SNOW SHOWERS REACHING THE PARK AND GORE RANGES BEFORE
MORNING. IN ADDITION...STRENGTHENING NORTHWEST FLOW ALOFT WILL
CAUSE WLY WINDS TO INCREASE IN SPEED ON MTN RIDGES AND UPPER EAST
SLOPES OF THE FRONT RANGE AFTER MIDNIGHT. IN THESE AREAS COULD
SEE GUSTS IN THE 40-50 MPH RANGE. OTHERWISE IT WILL REMAIN DRY AT
LOWER ELEVATIONS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 400 AM MST FRI JAN 2 2015
MAIN CONCERN WILL BE IMPACT FROM THE UPPER LEVEL TROF WHICH WILL
MOVE RAPIDLY FROM THE NORTHERN ROCKIES AND THROUGH COLORADO ON
SATURDAY. ASSOCIATED COLD FRONT WILL MOVE SOUTHWARD OVER THE
PLAINS MIDDAY ON SATURDAY WITH INCREASING NORTHERLY UPSLOPE FLOW
AND MOISTURE DURING THE AFTERNOON. MODEST QG UPWARD FORCING/JET
DYNAMICS AND RATHER STEEP LAPSE RATES WILL RESULT IN A WINDOW OF
SNOW SATURDAY AFTERNOON AND EVENING OVER MUCH OF CWA. GIVEN THE
STEEPENING LAPSE RATES AND INFLUX OF COLDER AIR...COULD SEE A FEW
HOURS OF MODERATE TO HEAVY SNOW OVER PORTIONS OF THE PLAINS.
LATEST GFS/NAM SHOWING 1-4 INCHES OF SNOW WHILE EUROPEAN A BIT
LESS WITH 1-2 INCHES. WITH MORE MODEL CONSISTENCY IN THE RUN TO
RUNS SHOWING UP IN THE PAST FEW DAYS...WILL BOOST POPS UP TO
LIKELY FOR MUCH OF THE AREA.
BEHIND THE DISTURBANCE...THE FLOW WILL INCREASE FROM THE
NORTHWEST WITH SOME DEVELOPMENT OF DOWNSLOPE WINDS OVER THE
MOUNTAINS AND EAST SLOPES FROM SUNDAY THROUGH TUESDAY. GUSTS IN
THE 50-70 MPH RANGE IS POSSIBLE SO WILL HAVE TO WATCH FOR
POTENTIAL FOR HIGH WINDS IN THESE PERIODS. WITH THE DOWNSLOPE
WINDS...TEMPERATURES WILL WARM TO SEASONAL NORMALS ACROSS LOWER
ELEVATIONS. LATEST LONG RANGE MODELS ARE NOW SHOWING ANOTHER
INFLUX OF COLDER AIR AND CHANCE OF PRECIP LATE TUESDAY AFTERNOON
AND NIGHT. WILL ADD SOME LOW POPS OVER THE FAR NORTHEAST CORNER IN
PROXIMITY TO THE UPPER JET. WITH THIS FLOW PATTERN...THE NORTHERN
MOUNTAINS WILL BE SUSCEPTIBLE TO A CHANCE OF LIGHT SNOW THROUGH
TUESDAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 400 AM MST FRI JAN 2 2015
5000-7000 FT AGL CIGS OVER DENVER AREA TERMINALS THROUGH 13Z...
THEN LOOK FOR CLEARING SKIES AS DRIER AIR SPREADS DOWN FROM THE
NORTHWEST. WEST-SOUTHWEST WINDS UNDER 10KTS FORECAST TO GO
SOUTHERLY AT SIMILAR SPEEDS BY MID-MORNING...THEN MORE
SOUTHEASTERLY BY EARLY AFTERNOON. WINDS AT KDEN...KAPA AND KBJC
ARE EXPECTED TO RETURN TO A SOUTH-SOUTHWEST DIRECTION AT 6-12KTS
AFTER 22Z AND REMAIN THERE OVERNIGHT UNDER CLEAR TO MOSTLY CLEAR
SKIES.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...BAKER
LONG TERM...ENTREKIN
AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
944 PM MST THU JAN 1 2015
.UPDATE...
ISSUED AT 609 PM MST THU JAN 1 2015
THE WINTER STORM WARNING FOR THE CORTEZ AREA WAS ALLOWED TO
EXPIRE. OCCASIONAL SNOWFALL WILL CONTINUE BUT ADDITIONAL
ACCUMULATE SHOULD BE LESS THAN 2 INCHES.
&&
.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 320 PM MST THU JAN 1 2015
THE HEAVIEST SNOWFALL OCCURRED LATE LAST NIGHT AND EARLY THIS
MORNING ACROSS THE FOUR CORNERS REGION AS PREDICTED. REPORTS
INDICATED 3 TO 5 INCHES OF SNOWFALL ACROSS MUCH OF THE REGION
WITH SNOWFALL RATES NEAR 1 INCH PER HOUR IN SOME LOCATIONS. UPWARD
FORCING IMPRESSIVE DURING THIS PERIOD AHEAD OF MID-LEVEL LOW
CENTERED OVER NORTH-CENTRAL ARIZONA. AT 12Z...GOOD SURFACE
CONVERGENCE IN EVIDENCE WITH SURFACE LOW CENTERED SOUTH OF KDRO
ACCORDING TO RAP ANALYSIS. CONCURRENTLY...STRONG MID-LEVEL QG
ASCENT OVER THE AREA TOPPED BY DIVERGENCE AT HIGHER LEVELS OF THE
TROPOSPHERE WHERE LEFT EXIT REGION OF JET WAS POSITIONED.
HOWEVER...DURING THE AFTERNOON COVERAGE AND SNOWFALL RATES HAD
DECREASED SIGNIFICANTLY AS FORCING WAS DIMINISHED. SOUTHWESTWARD
FLOWING JET ON THE BACK SIDE OF THE LOW CONTINUED TO PROPAGATE TO
THE SOUTHWEST WHILE THE NORTHEASTWARD FLOWING JET ON THE LEADING
EDGE MOVED OVER THE SOUTHERN PLAINS. THE SHEARING MOMENT BETWEEN
THESE FLOWS STRETCHED THE LOW ALONG A SOUTHWEST TO NORTHEAST AXIS.
AS A RESULT...DYNAMIC FORCING SHIFTED TO THE NORTHEAST CAUSING THE
SURFACE AND 7H LOW CIRCULATIONS TO MOVE IN THAT DIRECTION. IN
ADDITION TO THE LOSS OF DYNAMIC FORCING OVER THE SOUTHERN FORECAST
AREA...OROGRAPHIC LIFT ALSO IMPACTED AS WEAK 7H LOW RECENTERED
OVER THE SAN JUANS RESULTING IN WEAK AND VARIED WINDS.
MODELS IN GOOD AGREEMENT...GENERATING VERY LITTLE QPF OVER MOST OF
THE LOWER ELEVATIONS OF SOUTHEAST UTAH AND SOUTHWEST COLORADO
DURING THE REMAINDER OF THE AFTERNOON AND THIS EVENING. THEREFORE
...WILL CANCEL WINTER STORM WARNINGS FOR THESE AREAS WITH THIS
PACKAGE. HOWEVER...RAP13 AND HRRR BOTH INDICATED MODERATE SNOWFALL
WILL CONTINUE ALONG A SOUTHWEST TO NORTHEAST ORIENTED BAND
CENTERED OVER KCEZ. CONSEQUENTLY...WILL HOLD ONTO WINTER STORM
WARNING FOR MODERATE SNOWFALL OVER THE SOUTHWEST CORNER OF THE
STATE. IN ADDITION...LIGHT TO MODERATE SNOW SHOULD CONTINUE OVER
THE SAN JUAN MOUNTAINS WHILE COVERAGE INCREASES OVER THE CENTRAL
COLORADO MOUNTAINS AS DYNAMIC FORCING BECOMES MORE FAVORABLE. ONLY
EXPECTING 2 TO 4 INCHES WITH LOCALLY HIGHER AMOUNTS IN THE CENTRAL
MOUNTAINS SO WILL NOT EXPAND WINTER WEATHER ADVISORIES...THOUGH
WILL CONTINUE HILITES ACROSS THE SAN JUANS INTO THE EVENING.
SUBSIDENCE AND DRYING SETS IN LATER TONIGHT AS THE LOW CENTER IS
DRIVEN SOUTHWARD BY THE SOUTHWESTWARD PROPAGATING JET ON THE LOW/S
REAR FLANK. AS A RESULT...SNOWFALL WILL DIMINISH TO A FEW
FLURRIES OVER THE CENTRAL MOUNTAINS AFTER MIDNIGHT. ANTICYCLONIC
FLOW TO THE NORTH WILL INHIBIT SNOWFALL FRIDAY...THOUGH CANNOT
ENTIRELY RULE OUT A FEW FLURRIES ALONG THE DIVIDE FRIDAY
AFTERNOON. A SHORTWAVE TROUGH DROPPING TOWARD THE REGION FROM THE
NORTHWEST WILL BE THE NEXT SNOW PRODUCER OVER THE FORECAST AREA
POSSIBLY IMPACTING THE NORTHERN COLORADO MOUNTAINS FRIDAY NIGHT.
THE AREA WILL BE UNDER WARM AIR ADVECTION WHILE FLOW REMAINS
ANTICYCLONIC SO EXPECT SNOW WILL BE SCATTERED AND LIGHT...LIKELY
HOLDING OFF UNTIL AFTER MIDNIGHT AS INDICATED BY FAVORED GFS AND
ECMWF SOLUTIONS.
WAA WILL ALLOW AIRMASS TO MODERATE A BIT...BUT TEMPERATURES WILL
REMAIN COLDER THAN NORMAL FOR THE LATTER PART OF THE WEEK.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 320 PM MST THU JAN 1 2015
EXPECT SNOW WILL INCREASE OVER THE NORTHERN COLORADO MOUNTAINS
SATURDAY AS THE SHORTWAVE TROUGH DISCUSSED PREVIOUSLY PUSHES
ACROSS SOUTHWEST WYOMING IN THE MORNING...THEN ACROSS NORTHWEST
COLORADO DURING THE AFTERNOON. MODELS NOT GENERATING SIGNIFICANT
SNOW ACCUMULATIONS AT THIS POINT...BUT THERE REMAINS THE POTENTIAL
FOR ADVISORY LEVEL SNOW ACROSS THE PARK...GORE...ELKHEAD...AND
FLATTOP RANGES. A TIGHTENING GRADIENT ALOFT BENEATH THE NOSE OF A
SOUTHWARD FLOWING 120 KT JET WILL GENERATE STRONG AND GUSTY
NORTHWEST WINDS ACROSS THE RIDGES GENERATING AREAS OF BLOWING
SNOW.
MODELS INDICATED ANOTHER SHORTWAVE IN THE NORTHWESTERLIES WILL
BRING SIMILAR CONDITIONS SUNDAY AFTERNOON THROUGH SUNDAY NIGHT...
THOUGH IT APPEARS TO BE WEAKER THAN SATURDAY/S SYSTEM. HOWEVER...
ECMWF INDICATED THAT OROGRAPHIC SNOWFALL COULD CONTINUE WELL INTO
MONDAY SO MAY BE MORE IMPACTFUL THAN DEPICTED NOW. A RIDGE OF HIGH
PRESSURE EASES EASTWARD FROM TUESDAY TO THURSDAY BRINGING DRY AND
MILDER CONDITIONS FOR THE MIDDLE PART OF THE COMING WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 945 PM MST THU JAN 1 2015
MVFR TO IFR CONDITIONS STILL IN PLACE ACROSS SEVERAL FORECAST
TERMINAL SITES IN SOUTHWEST COLORADO AS WEAK LIFT AND MOISTURE
CONTINUE TO WRAP WESTWARD INTO THE REGION. MODELS TREND CONTINUE
TO SUGGEST IMPROVEMENT THROUGH 02/09Z AS THIS SYSTEM SPLITS AND
LEAVES OUR CWA VOID OF UPPER SUPPORT. WITH RECENT PRECIPITATION
ALWAYS A CHANCE OF STRATUS AND FOG DEVELOPING SUCH AS THE CASE AT
DRO THIS EVENING. WILL CONTINUE TO MONITOR LOW CLOUD/FOG SATELLITE
IMAGERY AND TRY AND DEFINE BEST PERIODS WHEN LOWERED FLIGHT
CRITERIA WILL BE PREVAILING. WITH LACK OF UPPER SUPPORT AND DRYING
ALOFT TOMORROW MAINLY DRY CONDITIONS ARE EXPECTED. DENDRITIC
LAYERS STAY UNSATURATED THROUGH THE EVENING LEAVING ONLY LIGHT
OROGRAPHIC SHOWERS AS A THREAT AN IMPACTS TO FORECAST TERMINALS
APPEAR REMOTE ATTM.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT FOR COZ018.
WINTER STORM WARNING UNTIL MIDNIGHT MST TONIGHT FOR COZ019.
UT...WINTER STORM WARNING UNTIL MIDNIGHT MST TONIGHT FOR UTZ028.
&&
$$
UPDATE...CC
SHORT TERM...NL
LONG TERM...NL
AVIATION...TGJT
AREA FORECAST DISCUSSION
NWS TAUNTON MA
714 PM EST SAT JAN 3 2015
.SYNOPSIS...
APPROACHING LOW PRESSURE WILL CONTINUE TO SPREAD A WINTRY MIX OF
PRECIPITATION INTO SOUTHERN NEW ENGLAND THIS EVENING. THE
PRECIPITATION WILL CHANGE TO ALL RAIN TONIGHT INTO SUNDAY
MORNING. THE LOW WILL TRACK INTO THE ST LAWRENCE RIVER VALLEY
SUNDAY...BRINGING MILD BUT SHOWERY WEATHER TO THE REGION. THE
TRAILING COLD FRONT WILL BRING MORE SHOWERS SUNDAY AFTERNOON AND
EVENING FOLLOWED BY DRIER BUT MUCH COLDER WEATHER MONDAY. A PERIOD
OF SNOW SHOWERS ARE POSSIBLE TUESDAY AND TUESDAY NIGHT...FOLLOWED
BY BITTERLY COLD WEATHER FOR THE REMAINDER OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
730 PM UPDATE...
INITIAL BATCH OF PRECIP CONTINUES TO MOVE NORTHWARD ACROSS BOSTON
AND ESSEX COUNTY. A QUICK INCH IS EXPECTED ACROSS THE REGION. THE
FOCUS NOW TURNS TO THE SLEET/FREEZING RAIN TRANSITION. SURFACE OBS
AS WELL AS SPOTTER REPORTS IS INDICATING SLEET MIX FROM WESTERN
MASS DOWN TO SANDWICH, MA. HOWEVER ACROSS HFD-PVD-EWB SOUTHWARD IS
INDICATING FREEZING RAIN IS OCCURRING. NOTICE THAT 850 MB TEMP 0C
CONTINUES TO MOVE NORTHEASTWARD VERY QUICKLY ALLOWING FOR THESE
TRANSITION PERIODS TO OCCUR ACROSS THE REMAINDER OF SOUTHERN NEW
ENGLAND THROUGHOUT THE EVENING.
SURFACE WINDS ACROSS BDL AND BAF HAVE SHIFTED TO A NORTHERLY
DIRECTION...THIS IS A GOOD INDICATOR THAT SHALLOW COLD AIR/COLD
AIR DAMMING IS OCCURRING AND EXPECT THIS TO REMAIN THROUGHOUT THE
NIGHT. LATEST HRRR CONTINUES TO TREND SLIGHTLY COOLER IN THE CT
VALLEY SO FREEZING RAIN MAY LINGER TO 09-12Z SUN. IF THIS OCCURS
THEN ICE ACCRETION COULD BE SLIGHTLY HIGHER THEN FORECASTED. FOR
NOW THE OVERALL TREND IN THE FORECAST REMAINS ON TRACK.
TONIGHT...
DIGGING SHORTWAVE IN THE SOUTHERN PLAINS PER WATER VAPOR IMAGERY
WILL PUSH SOUTHERN STREAM SURFACE LOW TOWARDS THE ST. LAWRENCE
VALLEY BY TOMORROW AFTERNOON. A SECONDARY LOW PRESSURE SYSTEM LOOKS
TO DEVELOP ACROSS SOUTHERN NEW ENGLAND TONIGHT. THIS WEAK SURFACE
LOW WILL BE THE MAIN FOCUS ON THE WEATHER FOR TONIGHT.
12Z GUIDANCE IS IN EXCELLENT AGREEMENT IN SHOWING AN 800-850MB 2-4C
WARM NOISE PUSHING INTO SOUTHERN NEW ENGLAND AFTER 00Z. IN FACT
BETWEEN 00Z AND 06Z SOME GUIDANCE JUMPS 850MB TEMPS FROM 0C TO 7C.
THIS WILL ALLOW FOR A QUICK CHANGEOVER FROM SNOW TO SLEET SOUTHWEST
TO NORTHEAST THIS EVENING. THE TRANSITION WILL BE VERY QUICK ALONG
COASTAL REGIONS AS WELL AS ALONG THE I-95 CORRIDOR. IF TEMPS LINGER
AROUND FREEZING DURING THIS TRANSITION...A PERIOD OF FREEZING RAIN
MAY BE POSSIBLE ALLOWING FOR A TRACE OF ICE YIELDING TO SLICK TRAVEL
CONDITIONS THIS EVENING. THEREFORE HAVE NOT MADE ANY CHANGES TO THE
WINTER WEATHER HEADLINES.
BIGGEST CONCERN FOR THIS PERIOD HOWEVER IS THE POTENTIAL FOR ICE
ACCRETION ACROSS THE INTERIOR. AS MENTIONED BEFORE...A GOOD WARM
LAYER WILL MOVE INTO SOUTHERN NEW ENGLAND. THIS WILL ALLOW FOR SNOW
TO TRANSITION TO SLEET THEN TO FREEZING RAIN. BIGGEST CONCERN IS
ACROSS THE CONNECTICUT VALLEY REGION WHERE SHALLOW COLD AIR WILL
REMAIN TRAPPED THANKS TO MARITIME HIGH PRESSURE AND WEAK LOW MOVING
ACROSS SOUTHERN NEW ENGLAND. WITH TEMPS BELOW 32F AND STRONG WARM
LAYER ALOFT...ANTICIPATE ABOUT 0.15-0.35 INCH OF ICE
ACCRETION...WITH HIGHER AMOUNTS POSSIBLE. THIS MUCH ICE WILL MAKE
TRAVEL DIFFICULT AND COULD ALSO RESULT IN A FEW POWER OUTAGES AND
DOWN LIMBS. LUCKILY THE WINDS WILL BE RELATIVELY LIGHT SO WIDESPREAD
POWER OUTAGES ARE NOT ANTICIPATE. GUIDANCE ALWAYS TRIES TO SCOURING
THE TEMPS OUT TOO FAST FOR THIS REGION SO LINGERED SHALLOW COLD AIR
A LITTLE LONGER THEN WHAT MODELS ADVERTISE. BELIEVE THAT AREAS IN
THE WINTER STORM WARNING HAVE THE BEST CHANCE TO SEE A FEW POWER
OUTAGES AND THE HIGHER ICE ACCRETION...SO WILL CONTINUE THE WARNING.
LASTLY...AS THE SURFACE LOW DEVELOPS AND PASSES OVER SOUTHERN NEW
ENGLAND AND WARM AIR ALOFT SURGES NORTHWARD...A MODEST LLJ OF 50-60
KTS WILL DEVELOP OVER THE CAPE. HOWEVER BECAUSE IT IS A SOUTHERLY
JET IS WILL STRUGGLE TO MIX FULLY DOWN. HOWEVER COULD STILL SEE SOME
ISOLATED GUSTS NEAR 45 MPH ACROSS THE CAPE TONIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
TOMORROW...
MAIN SURFACE LOW OVER THE GREAT LAKES WILL PUSH INTO THE ST LAWRENCE
VALLEY TOMORROW. THIS WILL ALLOW FOR THE REMINDER OF THE COLUMN TO
WARM ABOVE 32F SO THE POTENTIAL FOR FREEZING RAIN ACROSS THE
INTERIOR WILL COME TO AN END. THE FOCUS THEN TRANSITIONS TO THE RAIN
AND WIND POTENTIAL.
SOUTHERN NEW ENGLAND WILL BE ON THE WARM SIDE OF THIS ANOMALOUS
SYSTEM WITH PWATS NEAR 3 TO 4 STAND DEVIATIONS AWAY AND 850 MB WINDS
ALSO 2 TO 3 STAND DEVIATIONS AWAY.
FOCUSING ON THE WINDS...LLJ WILL BE MORE OUT OF THE SW AT 925 MB
STREAMING BETWEEN 50-70 KTS. HOWEVER IT IS HARD TO MIX DOWN AT A
SOUTHERLY WIND AND MANY SOUNDINGS DO SHOW AN INVERSION THROUGHOUT
THE DAY. YET IT APPEARS THAT WE COULD HAVE HEAVY RAINFALL SO WITHIN
ANY HEAVY SHOWER MAY AID FOR THE STRONG WINDS TO MIX DOWN TO THE
SURFACE. THEREFORE WILL CONTINUE WITH THE WIND ADVISORY FOR THE CAPE
AND ISLANDS WHICH HAVE THE BEST CHANCE OF MIXING.
HEAVY RAINFALL IS A POTENTIAL AS THE LOW PRESSURE SYSTEMS COLD FRONT
BEGINS TO PUSH ACROSS THE REGION TOMORROW. THIS YIELDS TO PWATS
CLOSE TO AN 1.5 INCHES...ESP ACROSS THE SOUTH COAST. EVEN SOME OF
THE HI-RES GUIDANCE SHOWERS A POTENTIAL FOR SOME RAIN BANDS TO
DEVELOP AND TREK ACROSS SOUTHERN NEW ENGLAND...WHICH MAY YIELD TO
MINOR URBAN FLOODING THANKS TO A HIGH AMOUNT OF MOISTURE IN THE
ATMOSPHERE. ISOLATED THUNDER IS ALSO POSSIBLE AS SURFACE LI`S DROP
BELOW 0. ANY CONVECTION THAT DOES DEVELOP WILL ALSO YIELD TO A RISK
OF TRAINING AND URBAN FLOODING. THE BEST REGION FOR THIS TO OCCUR IS
ACROSS THE SOUTH COAST OF MA AND RI.
FINALLY SURFACE TEMPS WILL WARM THROUGHOUT THE DAY WITH PERHAPS A
FEW SPOTS HITTING CLOSE TO 60F. IF THAT DOES OCCUR THEN WE MAY MIX
OUT ALLOWING FOR WINDS TO GUST HIGHER AT THE SURFACE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...
* TURNING WINDY AND COLDER SUN NIGHT/MON
* CLIPPER BRINGS MAINLY LIGHT SNOW TUE/TUE NIGHT
* ARCTIC AIR FOLLOWS FOR LATE WEEK
SUNDAY NIGHT AND MONDAY...
RAIN SHOWERS END SUN NIGHT AS COLD FRONT HEADS OFFSHORE. CLEARING
SHOULD WORK INTO MUCH OF REGION OVERNIGHT WITH PLENTY OF SUNSHINE
MON...ASIDE FROM W MA WHERE SOME CLOUDINESS SHOULD LINGER AND
POSSIBLY A FEW SNOW SHOWERS DUE TO UPSTREAM LAKE EFFECT.
STRONG W FLOW DEVELOPS LATE SUN NIGHT AND ESPECIALLY MON DUE TO
COLD ADVECTION AND PRESSURE DIFFERENCE BETWEEN LOW PRESSURE WELL
TO OUR N AND HIGH PRESSURE BUILDING ACROSS OHIO VALLEY. GUSTS
SHOULD REACH 30-40 MPH MON...ESPECIALLY NEAR COAST WHERE MIXING
LAYER IS DEEPEST.
LOWS SHOULD DROP BACK INTO 20S/30S SUN NIGHT...AND ONLY RISE A
FEW DEGREES MON GIVEN STRONG COLD ADVECTION.
TUESDAY AND TUESDAY NIGHT...
12Z MODELS HAVE SPED UP TIMING OF CLIPPER SYSTEM A BIT AND SHOW
MOSTLY LIGHT SNOW DURING DAY AND INTO EVENING AS WARM FRONT LIFTS
THROUGH AND SECONDARY LOW FORMS OFFSHORE. THIS DOES NOT LOOK TO BE
SIGNIFICANT SNOWFALL EVENT BUT MANY AREAS WILL PROBABLY PICK UP
1-3 INCHES WITH POSSIBILITY OF 2-4 INCHES NEAR S COAST...CAPE COD
AND ISLANDS WHERE SOME OCEAN ENHANCEMENT WILL COME INTO PLAY ON S
FLOW.
WEDNESDAY AND THURSDAY...
WELL ADVERTISED PATTERN CHANGE GETS UNDERWAY AS DEEP TROUGH BUILDS
ACROSS EASTERN STATES AND ARCTIC FRONT SWEEPS THROUGH NEW ENGLAND
BRINGING COLDEST AIR OF SEASON. PATTERN REMAINS PROGRESSIVE
HOWEVER GIVEN LACK OF DOWNSTREAM BLOCKING SO THIS SHOT OF
BITTERLY COLD AIR WILL BE SHORT LIVED.
GENERALLY DRY WEATHER EXPECTED WITH GUSTY W WINDS...THOUGH WE
SHOULD SEE SOME CLOUDINESS AND PERHAPS SOME LAKE EFFECT SNOW
SHOWERS SURVIVE TRIP OVER BERKSHIRES IN THIS REGIME. CLOSER TO
COAST...BANDS OF OCEAN EFFECT SNOW WILL BE FOCUSED WELL OFFSHORE.
MODEL 2M TEMPERATURES SHOW STRONG POTENTIAL FOR SUBZERO COLD WED
NIGHT DOWN INTO MUCH OF CT...RI AND E MA. WENT A FEW DEGREES
COLDER THAN GUIDANCE /ESPECIALLY MOS WHICH HAS WARM BIAS/ AND AM
FORECASTING LOWS AS COLD AS -10 ACROSS NW MA AND DOWN TO ZERO
FROM ABOUT HARTFORD AND WILLIMANTIC TO THE I-495 CORRIDOR IN NE
MA...WITH SINGLE NUMBERS FARTHER S AND E EXCEPT TEENS ON OUTER
CAPE AND ISLANDS.
WIND CHILLS MAY REACH ADVISORY CRITERIA /-15 TO -20/ FROM E SLOPES
OF BERKSHIRES TO BOSTON/PROVIDENCE CORRIDOR WED NIGHT.
NOT MUCH OF A RECOVERY THU AS THERMAL TROUGH SETTLES OVER SOUTHERN
NEW ENGLAND. HIGHS SHOULD ONLY TOP OUT IN SINGLE NUMBERS ACROSS NW
MA AND HIGHER TERRAIN TO TEENS ELSEWHERE...EXCEPT NEAR 20 ON OUTER
CAPE AND ISLANDS. WIND CHILLS SHOULD REMAIN BELOW ZERO ACROSS MUCH
OF INTERIOR AND IN SINGLE NUMBERS ELSEWHERE.
FRIDAY AND SATURDAY...
NEXT COLD FRONT ALREADY APPROACHES FRI AS ANOTHER UPPER TROUGH
SETTLES INTO REGION. MOISTURE IS LIMITED WITH THIS FRONT AND WE
SHOULD ONLY SEE FEW SNOW SHOWERS OR FLURRIES AS IT MOVES THROUGH
FRI. AIRMASS IS NOT AS COLD AS WITH PREVIOUS SYSTEM SO
TEMPERATURES WILL ACTUALLY RECOVER AS WE HEAD INTO WEEKEND...
WITH HIGHS IN 20S/LOWER 30S BOTH DAYS.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SUNDAY/...
TONIGHT...ANY MVFR CONDITIONS WILL LOWER TO IN IFR WITHIN THE NEXT
HOUR OR TWO. SNOW WILL TRANSITION TO A SLEET/FREEZING RAIN MIX
FROM SOUTHWEST TO NORTHEAST AFTER 00Z. THIS WINTRY MIX WILL
EVENTUALLY TURN TO ALL RAIN ESP ALONG THE COAST. ANTICIPATE A SLOWER
PROCESS INLAND WITH PROLONGED PERIOD OF FREEZING RAIN NORTH CENTRAL
AND NORTHWEST MA. SOUTHEAST WINDS MAY GUSTS UP TO 40 KT OVER CAPE
COD AND ISLANDS AROUND MIDNIGHT. HIGH CONFIDENCE.
SUNDAY...
IFR BUT POSSIBLY IMPROVING TO MVFR IN THE AFTERNOON EXCEPT SOUTH
COAST WILL LIKELY STAY IN IFR. FREEZING RAIN LIKELY IN THE MORNING
ACROSS NORTHWEST MA. SHOWERS ELSEWHERE. HEAVY SHOWERS POSSIBLE
SOUTH COAST AFTN AND EVENING WITH EMBEDDED TSTM POSSIBLE. SOME
UNCERTAINTY ON STRENGTH OF WINDS AND INTENSITY OF SHOWERS SOUTH
COAST AFTN AND EVENING. MODERATE TO HIGH CONFIDENCE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF...SLIGHTLY LOWER IN EXACT
TIMING OF PRECIP CHANGEOVER.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF...SLIGHTLY LOWER IN EXACT
TIMING OF PRECIP CHANGEOVER AND CIGS.
OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY.
MODERATE CONFIDENCE.
SUNDAY NIGHT...MVFR/IFR IMPROVES TO VFR OVERNIGHT. INCREASING W
WINDS GUSTING TO 25-35KT.
MONDAY...VFR. W WINDS GUSTING TO 30-40KT...STRONGEST NEAR COAST.
TUESDAY...MVFR/IFR IN LIGHT SNOW.
WEDNESDAY AND THURSDAY...VFR. MVFR CIGS AROUND CAPE COD/ISLANDS
AND NEAR BERKSHIRES WITH ISOLATED SNOW SHOWERS POSSIBLE. W WINDS
GUSTING TO 20-30KT.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SUNDAY/...MODERATE TO HIGH CONFIDENCE.
TONIGHT...
SOUTHEAST WINDS INCREASE TO GALE FORCE ACROSS THE WATERS OF CAPE
COD AND THE ISLANDS. SNOW AND SLEET QUICKLY CHANGES TO RAIN.
TOMORROW... SW GALE MOST WATERS. SHOWERS POSSIBLY HEAVY SOUTH
COASTAL WATERS LOWERS VSBY.
OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
HIGH CONFIDENCE.
SUN NIGHT AND MON...
COLD FRONT MOVING OFFSHORE SUN NIGHT WILL BRING END TO SHOWERS...
BUT INCREASING W WINDS SHOULD REACH GALE FORCE ON ALL WATERS.
GALES SHOULD PERSIST INTO MON BEFORE DIMINISHING MON NIGHT. MAY BE
COLD ENOUGH FOR SOME FREEZING SPRAY...ESPECIALLY NEAR E MA COAST.
BANDS OF OCEAN EFFECT SNOW WILL BE FOCUSED OFFSHORE MON.
TUE...
WINDS BRIEFLY DIMINISH TUE AS LOW PRESSURE TRACKS THROUGH EASTERN
GREAT LAKES AND PUSHES WARM FRONT THROUGH NEW ENGLAND. MOSTLY
LIGHT SNOW EXPECTED DURING DAY AND INTO EVENING THOUGH VSBYS COULD
BRIEFLY LOWER TO 1SM OR LOWER NEAR S COAST.
WED AND THU...
W WINDS INCREASE AGAIN AND SHOULD REACH GALE FORCE ON OUTER WATERS
WITH SCA ELSEWHERE. LIGHT TO MODERATE FREEZING SPRAY LIKELY TO
DEVELOP AS ARCTIC AIR POURS INTO REGION. OCEAN EFFECT SNOWS SHOULD
BE FOCUSED OFFSHORE.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 10 AM EST SUNDAY FOR CTZ002>004.
MA...WIND ADVISORY FROM 7 AM TO 7 PM EST SUNDAY FOR MAZ020>022.
WINTER WEATHER ADVISORY UNTIL 2 AM EST SUNDAY FOR MAZ007-
013>015-017.
WINTER WEATHER ADVISORY UNTIL 10 AM EST SUNDAY FOR MAZ004>006-
010>012-026.
WINTER STORM WARNING UNTIL 10 AM EST SUNDAY FOR MAZ002-003-008-
009.
WIND ADVISORY FROM 7 AM TO 10 PM EST SUNDAY FOR MAZ023-024.
RI...WIND ADVISORY FROM 7 AM TO 7 PM EST SUNDAY FOR RIZ007-008.
WINTER WEATHER ADVISORY UNTIL 2 AM EST SUNDAY FOR RIZ002.
WINTER WEATHER ADVISORY UNTIL 10 AM EST SUNDAY FOR RIZ001.
MARINE...GALE WARNING UNTIL 6 PM EST SUNDAY FOR ANZ231>235-237-250-251-
254>256.
SMALL CRAFT ADVISORY UNTIL 7 AM EST SUNDAY FOR ANZ230.
GALE WARNING FROM 10 AM TO 6 PM EST SUNDAY FOR ANZ236.
&&
$$
SYNOPSIS...DUNTEN/JWD
NEAR TERM...DUNTEN
SHORT TERM...NOCERA
LONG TERM...JWD
AVIATION...DUNTEN/JWD
MARINE...DUNTEN/JWD
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
754 PM EST SAT JAN 3 2015
.UPDATE...WARM SLY FLOW CONTINUES OVER THE REGION WITH ELEVATED
DEW-POINT VALUES IN THE MID TO UPPER 60S. WEAK LOW LEVEL CONVERGENT
FLOW CONTINUES TO ALLOW FOR A FEW LOW TOPPED SHOWERS TO PERSIST OVER
EASTERN PORTIONS OF THE FORECAST AREA FROM MARION COUNTY NWD INTO
COASTAL SE GA. THESE MAY CONTINUE FOR THE NEXT FEW HOURS BEFORE
DISSIPATING TONIGHT. MAIN CONCERN FOR TONIGHT IS THE PROSPECTS FOR
FOG. WE HAVE SEEN VSBY AND CIGS GO DOWN AROUND BRUNSWICK AND ST
SIMONS ISLAND DUE TO ADVECTIVE FOG EFFECTS...AND THIS IS ON PAR
WITH GUIDANCE FROM THE HRRR AND THE NAM. THINK THE FOG WILL
GENERALLY INCREASE IN COVERAGE AND INTENSITY THROUGH LATE TONIGHT
BUT THE LOW LEVEL WINDS OF 5-10 MPH WILL LIKELY HINDER ITS
DURATION AND EXPANSION. FURTHER SW...THERE SEEMS LIKE A GOOD
CHANCE OF GULF SEA FOG AND STRATUS TO MOVE INTO THE SUWANNEE VALLEY
AREA AND THUS ADDED FOG FOR THIS REGION TONIGHT. ELSEWHERE...WITH
SOME DECREASE IN WIND SPEEDS LATER TONIGHT...PATCHY TO AREAS OF
FOG ARE A GOOD BET BUT AGAIN WITH THE SPEEDS STAYING UP DENSE FOG
COVERAGE MAY BE SOMEWHAT LIMITED AND SHORT IN DURATION. OTHERWISE...
TEMPS WILL BE MILD TONIGHT DUE TO CLOUDS AND WINDS.
&&
.AVIATION...CEILINGS GRADUALLY IMPROVED TO VFR THIS LATE AFTERNOON
AND EARLY EVENING. THE VFR CONDITIONS WILL BE SHORT LIVED. IFR TO
LIFR CONDITIONS ARE FORECAST NEAR KSSI WHERE COASTAL FOG MAY
ENVELOP THE TERMINAL RAPIDLY THIS EVENING. FOR DUVAL COUNTY
TERMINALS...AND GAINESVILLE TERMINAL...MVFR CONDITIONS ARE
EXPECTED WITH CIGS LOWERING BY LATE EVENING. CIGS WILL LOWER TO
IFR LATE TONIGHT INTO THE FIRST MORNING DAYLIGHT HOURS SUNDAY.
MODELS SUGGEST IMPROVEMENT TO VFR CONDITIONS BY 16Z SUNDAY AS SWLY
FLOW DEVELOPS AHEAD OF AN APPROACHING COLD FRONT. AHEAD OF THIS
FRONT...SCATTERED TO NUMEROUS SHOWERS ARE ANTICIPATED BETWEEN
20-24Z SUNDAY WITH ISOLD TSRA. CONFIDENCE IS LOW ON CONVECTION
DEVELOPING SO REFRAINED AT THIS TIME TO MENTION VCTS IN THIS TAF
CYCLE. LATER FORECASTS MAY DEPICT THUNDERSTORMS IN THE TAF LATE
SUNDAY AFTERNOON AND EARLY EVENING IF CONFIDENCE IS ENHANCED.
&&
.MARINE...SE TO S WIND FLOW HAS INCREASED BASED ON 41009 AND SAUF1
AND SO WILL CONTINUE WITH SCEC FOR THE OFFSHORE WATERS WHERE MIXING
WILL BE STRONGEST. CONFIDENCE HAS INCREASED ON THE SEA FOG FCST
ACROSS THE SE GA COASTAL WATERS. LOOKS LIKE IT WILL BE MAINLY
PATCHY TO AREAS OF SEA FOG IN THAT AREA BASED ON SOME OF THE
GUIDANCE AND EARLIER REPORTS...BUT HIGH CLOUDS ARE OBSCURING THE
EXTENT OF IT. SOME SEA FOG MAY IMPACT NE FL NEARSHORE WATERS BUT
LOW LEVEL WINDS OF ALMOST 10 KT WILL KEEP MAINLY A STRATUS LAYER
OR SOME OCCASIONAL LOW VSBY. WILL CONTINUE TO MONITOR AND FOR NOW
WILL HANDLE WITH MARINE WEATHER STATEMENTS BUT THERE IS A CHANCE
WE MAY NEED TO GO WITH A MARINE DENSE FOG ADVISORY FROM FERNANDINA
BEACH NWD.
RIP CURRENTS: LOW RISK OF RIP CURRENTS SUNDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 62 76 46 59 / 20 80 70 0
SSI 62 72 49 57 / 20 60 60 0
JAX 64 79 53 60 / 20 50 60 0
SGJ 65 77 56 59 / 20 30 50 20
GNV 63 77 56 62 / 20 50 60 10
OCF 65 79 58 64 / 20 30 50 20
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
SHASHY/CORDERO/WALKER
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
839 AM EST FRI JAN 2 2015
.UPDATE...FORECAST AREA TO REMAIN IN MOIST LAYER BENEATH FRONTAL
INVERSION WITH WEAK ISENTROPIC LIFT SUPPORTING WIDESPREAD LOW
CLOUD COVER TODAY. MODELS SHOW LIFT BREAKING DOWN SOME TODAY...
PARTICULARLY SOUTHERN AREAS WHERE WE MIGHT SEE SOME BREAKS IN
CLOUDINESS AND HIGHER AFTERNOON TEMPS AS A RESULT...AS SUGGESTED
BY CONSENSUS GUIDANCE. SEE LITTLE IN WAY OF PRECIP POTENTIAL FOR
OUR AREA OF RESPONSIBILITY TODAY..THOUGH WE MAY SEE A FEW SHOWERS
OCCUR JUST NORTHWEST OF OUR GA COUNTIES THIS AFTERNOON...KEPT 10-20
POPS FOR OUR NORTHWESTERNMOST COUNTIES TODAY.
WILL MAINTAIN CURRENT HIGH TEMP FORECAST OF MID/UPR 60S I-10
CORRIDOR NORTHWARD...WITH MID 70S POSSIBLE MARION/FLAGLER COUNTIES.
&&
.AVIATION...IFR CIGS THIS MORNING. HRRR GUIDANCE SUGGESTS CIGS RISE
CLOSE TO BKN030 THIS AFTN...AND TAFS SHOW THIS TREND. EXPECT CIGS
TO LOWER TO IFR BY LATE TONIGHT.
&&
.MARINE...NO SIGNIFICANT CHANGES PLANNED IN CWF UPDATE.
A COASTAL TROUGH WILL MOVE NORTHEAST ACROSS THE COASTAL WATERS
THROUGH TONIGHT. HIGH PRESSURE WILL BUILD EAST OF AREA WATERS LATE
TONIGHT THROUGH SATURDAY NIGHT. A COLD FRONT WILL MOVE SOUTHEAST
ACROSS THE WATERS SUNDAY NIGHT. THIS BOUNDARY WILL STALL NEAR THE
REGION THROUGH TUESDAY. STRONG HIGH PRESSURE WILL BUILD NORTHWEST OF
THE REGION TOWARD MID WEEK...WHICH COULD LEAD TO ELEVATED WINDS AND
SEAS.
RIP CURRENTS: LOW RISK TODAY AND SATURDAY WITH 10KT NE WINDS AND
DECREASING HEIGHT/PERIOD OF EASTERLY SWELL.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 65 54 76 62 / 10 20 30 30
SSI 63 58 71 61 / 10 10 20 20
JAX 69 58 79 63 / 10 10 30 20
SGJ 70 62 78 66 / 10 10 30 20
GNV 72 58 81 62 / 10 10 30 20
OCF 75 61 83 65 / 10 10 20 20
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
WOLF/ENYEDI/WALSH
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
638 PM EST SAT JAN 3 2015
.PREV DISCUSSION... /ISSUED 308 PM EST SAT JAN 3 2015/
..SEVERE STORMS POSSIBLE NW GEORGIA AFTER MIDNIGHT...
..HEAVY RAIN LIKELY MUCH OF NORTH GEORGIA TONIGHT AND SUNDAY
MORNING...
SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
ONLY MINOR REFINEMENTS MADE TO GRIDS SINCE LAST DISCUSSION /SEE
BELOW/ BASED ON OBSERVED TRENDS AND LATEST HRRR GUIDANCE. APPEARS
LINE OF CONVECTION STILL ON TARGET TO MOVE INTO NW GEORGIA AFTER
06Z THEN PUSH INTO ATL METRO AROUND 11-12Z WHILE ON A WEAKENING
TREND. WIDESPREAD DRIZZLE AND FOG WITH SCT -SHRA TO CONTINUE
UNTIL THEN.
PRECIP SHOULD END QUICKLY BEHIND MAIN PRE-FRONTAL SQUALL LINE.
HAVE MANUALLY DRAWN POPS AS LACK OF GOOD HOURLY MODEL GUIDANCE
EXISTS TODAY. COULD SEE VERY ISOLD CONVECTION BEHIND THIS LINE SUN
AFTERNOON BUT SUBJECTIVE EXPERIENCE IN THIS PATTERN IS COVERAGE
AND INTENSITY WILL BE MUCH LESS THAN INDICATED BY MODEL GUIDANCE.
WINDS SHOULD BE STRONG BUT REMAIN BELOW ADVISORY CRITERIA SUN AND
SUN EVENING.
SNELSON
LONG TERM /MONDAY THROUGH SATURDAY/...
VERY FEW CHANGES NEEDED FOR THE LONG TERM PORTION OF THE FORECAST.
HIGH PRESSURE WILL MOVE OFFSHORE THE MID ATLANTIC COAST ON MONDAY IN
ADVANCE OF A COLD FRONT ON TUESDAY. TUESDAYS FRONT IS EXPECTED TO BE
DRY.
A STRONG AREA OF HIGH PRESSURE WILL BUILD BEHIND THE FRONT WEDNESDAY
INTO THURSDAY...BRINGING A MUCH COLDER AND DRIER AIRMASS TO THE
SOUTHEAST STATES. THERE WERE SOME EARLIER DIFFERENCES BETWEEN THE
LONGER TERM MODELS WITH FORECAST MINS AND MAX TEMPS WEDNESDAY INTO
THURSDAY...THE GFS HAS TRENDED A LITTLE COLDER AND CLOSER TO THE
ECMWF VALUES.
IN ADDITION TO THE COLDER TEMPERATURES...BREEZY OR EVEN WINDY
CONDITIONS ARE EXPECTED WEDNESDAY INTO EARLY THURSDAY. VALUES COULD
APPROACH WIND ADVISORY CRITERIA...AND BRING LOW WIND CHILLS.
TEMPERATURES ARE EXPECTED TO MODERATE FAIRLY QUICKLY FRIDAY INTO
THE WEEKEND.
NLISTEMAA
HYDROLOGY...
STILL ON TRACK TO SEE 1 TO 2 INCHES WITH AMOUNTS OVER 1.5 INCHES
CONFINED TO NE GA. BASED ON THIS EXPECTATION AND FFG HAVE DECIDED
NOT TO ISSUE ANY KIND OF FLOOD WATCH. WILL CONTINUE TO MONITOR
THIS EVENING.
SNELSON
PREV DISCUSSION... /ISSUED 149 PM EST SAT JAN 3 2015/
UPDATE... NEAR TERM FCST APPEARS ON TRACK. MAIN CONCERN IS
POTENTIAL FOR SVR STORMS AND HVY RAIN. 12Z SYNOPTIC MODELS AND
HIRES GUIDANCE INDICATING LINE OF CONVECTION SHOULD MOVE INTO NW
CORNER AROUND OR AFTER 06Z. NAM AND GFS 0-1KM BULK SHEAR
/35-45KTS/ AND MLCAPE /100-250 J/KG/ FAVORABLE FOR QLCS STORMS
WITH ISOLD WIND DMG AND EVEN BRIEF TORNADO POSSIBLE IN THE NW
1/3RD OF GA BETWEEN 06Z AND 12Z...MAINLY NORTH OF I-85.
LATEST QPF GUIDANCE INDICATING 1 TO 2 INCHES THRU 00Z MON WITH
ONLY NE GA AREA EXPECTING AMOUNTS OF 1.5 INCHES. 3HR FFG IS QUITE
LOW /2-2.5 INCHES/ IN NORTH GA DUE TO ANTECEDENT RAINFALL THE LAST
36 HRS. WILL BE COLLABORATING AND LOOKING AT A LITTLE MORE DATA
BEFORE DECIDING BUT FOR NOW HOLDING OFF ON WATCH.
SNELSON
&&
.AVIATION...
00Z UPDATE...
WARM FRONT WILL BE MOVING NORTHWARD THRU TONIGHT..REACHING ATL/AHN
BETWEEN 06Z AND 09Z. LIFR CONDITIONS WILL CONTINUE NORTH OF THE
FRONT. SOUTH OF THE FRONT SOME AREAS HAVE BECOME VFR...HOWEVER
EXPECT IFR CIGS TO DEVELOP THIS EVENING. SCATTERED
SHOWERS/DRIZZLE WILL CONTINUE AT MOST AREAS THRU TONIGHT. HEAVY
RAIN AND ISOLATED TSRA WILL MOVE INTO THE ATL/CSG AREA EARLY
SUNDAY MORNING AND MOVE ACROSS THE FORECAST AREA INTO THE
AFTERNOON. RAPIDLY IMPROVING CONDITIONS BEHIND THE FRONT WITH ALL
AREAS VFR BY LATE AFTERNOON. WINDS WILL BECOME WEST/NORTHWEST
BEHIND THE FRONT AND GUSTY.
//ATL CONFIDENCE...00Z UPDATE...
MEDIUM ON ALL ELEMENTS.
17
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 53 65 35 54 / 40 100 10 0
ATLANTA 57 62 34 50 / 60 100 10 0
BLAIRSVILLE 52 58 29 46 / 90 100 10 5
CARTERSVILLE 55 61 31 46 / 100 100 10 0
COLUMBUS 63 67 36 53 / 40 100 10 0
GAINESVILLE 49 61 33 50 / 50 100 10 0
MACON 63 69 37 55 / 30 100 10 5
ROME 55 60 30 45 / 100 100 10 5
PEACHTREE CITY 59 63 34 51 / 60 100 10 0
VIDALIA 63 75 42 58 / 50 80 70 5
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...17
LONG TERM....BAKER
AVIATION...17
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1223 PM EST FRI JAN 2 2015
.SYNOPSIS...
MOISTURE WILL INCREASE ACROSS THE AS A LOW PRESSURE SYSTEM AND
COLD FRONT APPROACHES THE REGION FROM THE WEST. THE CHANCE OF RAIN
WILL INCREASE THROUGH THE WEEKEND WITH BEST CHANCES SUNDAY
AFTERNOON AS A COLD FRONT MOVES ACROSS THE AREA. COLD HIGH
PRESSURE AND DRY CONDITIONS WILL BUILD BACK INTO THE REGION SUNDAY
NIGHT AND MONDAY THROUGH MID-WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NEAR TERM...
WATER VAPOR IMAGERY SHOWING THE UPPER LOW OVER THE DESERT
SOUTHWEST STARTING TO CLOSE OFF WHILE AN UPPER HIGH OVER CUBA
RIDGES INTO THE SOUTHEASTERN STATES. SURFACE HIGH PRESSURE
CONTINUES TO BE CENTERED OVER THE REGION WITH GENERALLY LIGHT AND
VARIABLE WINDS.
REGIONAL RADAR SHOWING A LARGE AREA OF PRECIPITATION MOVING ACROSS
ALABAMA INTO NORTHWEST GEORGIA ASSOCIATED WITH WEAK SHORTWAVE ENERGY
ROUNDING THE TOP OF THE UPPER RIDGE AXIS...AIDED BY ISENTROPIC
LIFTING OF THE SOUTHWESTERLY FLOW ATOP THE COOLER SURFACE LAYER.
SOME SCATTERED SHOWERS HAVE WORKED INTO THE CSRA AND FAR WESTERN
MIDLANDS LATE THIS MORNING BUT KEEP DIMINISHING AS THEY MOVE
EASTWARD INTO RELATIVELY DRIER AIR AND AWAY FROM THE SOURCE OF LIFT
FURTHER TO THE WEST. LATEST HRRR RUNS SHOW THE AREA OF
PRECIPITATION TO THE WEST MOVING INTO THE WESTERN MIDLANDS BY THIS
AFTERNOON AND WILL CARRY HIGHEST POPS THERE WITH A GRADIENT TO LOWER
POPS FURTHER SOUTH AND EAST. OVERALL RAINFALL AMOUNTS EXPECTED TO
BE LIGHT AS THE PRECIPITATION IS FALLING OUT OF MAINLY MID LEVEL
CLOUDS...THOUGH THE CLOUD DECKS ARE EXPECTED TO LOWER THROUGH THE
AFTERNOON FROM WEST TO EAST.
VISIBLE IMAGERY SHOWING GENERALLY THIN HIGH CLOUDS ACROSS THE
SOUTHEASTERN MIDLANDS WHICH HAS ALLOWED TEMPS TO RISE MORE
QUICKLY THERE THAN FURTHER TO THE WEST WHERE THICKER CLOUDS ARE
PRESENT. RAISED MAX TEMPS A BIT TO ACCOUNT FOR THIS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
MODELS STRENGTHEN WEDGE TONIGHT INTO SATURDAY WITH THE SURFACE
RIDGE CENTER IN FAVORABLE LOCATION IN THE NORTHEASTERN STATES
EXTENDING SOUTHWEST ACROSS THE CAROLINAS. STRONG WARM ADVECTION
AND MOISTURE TRANSPORT JUST ABOVE THE WEDGE WILL BEGIN TO ERODE
THE WEDGE FROM THE SOUTH LATE SATURDAY AND SATURDAY NIGHT. MODELS
LIFT WARM FRONT NORTH THROUGH THE CWA LATE SATURDAY NIGHT. MIN
TEMPS SATURDAY NIGHT WILL LIKELY OCCUR IN THE EVENING WITH RISING
TEMPS AFTER MIDNIGHT. STRONG WARM MOIST ADVECTION CONTINUES AHEAD
OF AN APPROACHING COLD FRONT ON SUNDAY. TEMPERATURES ARE FORECAST
TO RISE INTO THE 70S WITH MOS DEWPOINTS INTO THE LOWER 60S.
INSTABILITY WILL INCREASE JUST AHEAD OF THE FRONT WHICH IS PROGGED
TO PASS THROUGH THE AREA BETWEEN 18Z AND 00Z SUNDAY. GFS IS ABOUT
3-H FASTER THAN NAM WITH FRONTAL PASSAGE. LI/S AHEAD OF THE FRONT
REACH -1 TO -3 WITH STRONG SHEAR AND A 5KT WIND SPEED IN THE
50-55KT RANGE.
POPS WILL BE GENERALLY IN THE 40-60 PERCENT RANGE
TONIGHT AND SATURDAY WITH THE STRONG WAA...DECREASING SIGHTLY TO
THE 30-50 PERCENT RANGE SATURDAY NIGHT AS WE TRANSITION TO THE
WARM SECTOR...THEN INCREASE ON SUNDAY TO NEAR 100 PERCENT IN A
CONVECTIVE LINE AHEAD OF THE COLD FRONT. HAVE THUNDER IN THE
FORECAST. WITH THE STRONG SHEAR...SOME INSTABILITY AND A STRONG
LOW LEVEL WIND FIELD WE WILL NEED TO MONITOR THE SITUATION FOR THE
POTENTIAL OF SEVERE WEATHER.
SUNDAY NIGHT SKIES WILL CLEAR...WINDS WILL TURN TO THE WEST
NORTHWEST AND TEMPS WILL COOL DOWN INTO THE LOWER 40S BEHIND THE
COLD FRONT.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
GFS...ECMWF...CMC MODELS SIMILAR WITH A COUPLE OF UPPER TROFS
AFFECTING THE FORECAST AREA NEXT WEEK. SURFACE HIGH PRESSURE WITH
ARCTIC AIR DIVES SOUTH WITH THE SECOND TROF BRINGING MUCH COLDER
TEMPERATURES BY MIDWEEK. TEMPERATURES OVERALL WILL BE BELOW
NORMAL...ESPECIALLY WEDNESDAY ON. NO PRECIPITAION EXPECTED.
&&
.AVIATION /17Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS EXPECTED THROUGH MUCH OF THE PERIOD...WITH
DIMINISHING CONDITIONS AFTER 06Z.
VFR CONDITIONS TO START THE FORECAST PERIOD WITH GENERALLY OVERCAST
MID LEVEL CLOUDS BUT COULD SEE SOME LOWER VFR CEILINGS IN PATCHES OF
RAIN THAT WILL BE MOVING INTO THE AREA FROM THE WEST...ASSOCIATED
WITH WEAK ISENTROPIC LIFT. LIGHT AND VARIABLE WINDS THROUGHOUT THE
FORECAST PERIOD ALTHOUGH A GENERAL PREVAILING NORTHEASTERLY
DIRECTION IS EXPECTED LATE TONIGHT INTO SATURDAY MORNING AS A COLD
AIR DAMMING WEDGE DEVELOPS. AS THE WEDGE DEVELOPS LATE
TONIGHT...CEILINGS ARE EXPECTED TO DROP INTO MVFR RANGE AFTER 06Z
THEN FALL INTO IFR CATEGORY AFTER AROUND 12Z FOR ALL TERMINALS.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS FOR BOTH CEILINGS AND
VISIBILITIES EXPECTED SATURDAY AFTERNOON AND NIGHT IN THE WEDGE THEN
SOME IMPROVEMENT EXPECTED ON SUNDAY. MORE RESTRICTIONS POSSIBLE WITH
A COLD FRONT SUNDAY AFTERNOON/EVENING. THUNDERSTORMS MAY IMPACT TAF
SITES SUNDAY AFTERNOON.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
99/87
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1156 AM EST FRI JAN 2 2015
.SYNOPSIS...
MOISTURE WILL INCREASE ACROSS THE AS A LOW PRESSURE SYSTEM AND
COLD FRONT APPROACHES THE REGION FROM THE WEST. THE CHANCE OF RAIN
WILL INCREASE THROUGH THE WEEKEND WITH BEST CHANCES SUNDAY
AFTERNOON AS A COLD FRONT MOVES ACROSS THE AREA. COLD HIGH
PRESSURE AND DRY CONDITIONS WILL BUILD BACK INTO THE REGION SUNDAY
NIGHT AND MONDAY THROUGH MID-WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NEAR TERM...
WATER VAPOR IMAGERY SHOWING THE UPPER LOW OVER THE DESERT
SOUTHWEST STARTING TO CLOSE OFF WHILE AN UPPER HIGH OVER CUBA
RIDGES INTO THE SOUTHEASTERN STATES. SURFACE HIGH PRESSURE
CONTINUES TO BE CENTERED OVER THE REGION WITH GENERALLY LIGHT AND
VARIABLE WINDS.
REGIONAL RADAR SHOWING A LARGE AREA OF PRECIPITATION MOVING ACROSS
ALABAMA INTO NORTHWEST GEORGIA ASSOCIATED WITH WEAK SHORTWAVE ENERGY
ROUNDING THE TOP OF THE UPPER RIDGE AXIS...AIDED BY ISENTROPIC
LIFTING OF THE SOUTHWESTERLY FLOW ATOP THE COOLER SURFACE LAYER.
SOME SCATTERED SHOWERS HAVE WORKED INTO THE CSRA AND FAR WESTERN
MIDLANDS LATE THIS MORNING BUT KEEP DIMINISHING AS THEY MOVE
EASTWARD INTO RELATIVELY DRIER AIR AND AWAY FROM THE SOURCE OF LIFT
FURTHER TO THE WEST. LATEST HRRR RUNS SHOW THE AREA OF
PRECIPITATION TO THE WEST MOVING INTO THE WESTERN MIDLANDS BY THIS
AFTERNOON AND WILL CARRY HIGHEST POPS THERE WITH A GRADIENT TO LOWER
POPS FURTHER SOUTH AND EAST. OVERALL RAINFALL AMOUNTS EXPECTED TO
BE LIGHT AS THE PRECIPITATION IS FALLING OUT OF MAINLY MID LEVEL
CLOUDS...THOUGH THE CLOUD DECKS ARE EXPECTED TO LOWER THROUGH THE
AFTERNOON FROM WEST TO EAST.
VISIBLE IMAGERY SHOWING GENERALLY THIN HIGH CLOUDS ACROSS THE
SOUTHEASTERN MIDLANDS WHICH HAS ALLOWED TEMPS TO RISE MORE
QUICKLY THERE THAN FURTHER TO THE WEST WHERE THICKER CLOUDS ARE
PRESENT. RAISED MAX TEMPS A BIT TO ACCOUNT FOR THIS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
MODELS STRENGTHEN WEDGE TONIGHT INTO SATURDAY WITH THE SURFACE
RIDGE CENTER IN FAVORABLE LOCATION IN THE NORTHEASTERN STATES
EXTENDING SOUTHWEST ACROSS THE CAROLINAS. STRONG WARM ADVECTION
AND MOISTURE TRANSPORT JUST ABOVE THE WEDGE WILL BEGIN TO ERODE
THE WEDGE FROM THE SOUTH LATE SATURDAY AND SATURDAY NIGHT. MODELS
LIFT WARM FRONT NORTH THROUGH THE CWA LATE SATURDAY NIGHT. MIN
TEMPS SATURDAY NIGHT WILL LIKELY OCCUR IN THE EVENING WITH RISING
TEMPS AFTER MIDNIGHT. STRONG WARM MOIST ADVECTION CONTINUES AHEAD
OF AN APPROACHING COLD FRONT ON SUNDAY. TEMPERATURES ARE FORECAST
TO RISE INTO THE 70S WITH MOS DEWPOINTS INTO THE LOWER 60S.
INSTABILITY WILL INCREASE JUST AHEAD OF THE FRONT WHICH IS PROGGED
TO PASS THROUGH THE AREA BETWEEN 18Z AND 00Z SUNDAY. GFS IS ABOUT
3-H FASTER THAN NAM WITH FRONTAL PASSAGE. LI/S AHEAD OF THE FRONT
REACH -1 TO -3 WITH STRONG SHEAR AND A 5KT WIND SPEED IN THE
50-55KT RANGE.
POPS WILL BE GENERALLY IN THE 40-60 PERCENT RANGE
TONIGHT AND SATURDAY WITH THE STRONG WAA...DECREASING SIGHTLY TO
THE 30-50 PERCENT RANGE SATURDAY NIGHT AS WE TRANSITION TO THE
WARM SECTOR...THEN INCREASE ON SUNDAY TO NEAR 100 PERCENT IN A
CONVECTIVE LINE AHEAD OF THE COLD FRONT. HAVE THUNDER IN THE
FORECAST. WITH THE STRONG SHEAR...SOME INSTABILITY AND A STRONG
LOW LEVEL WIND FIELD WE WILL NEED TO MONITOR THE SITUATION FOR THE
POTENTIAL OF SEVERE WEATHER.
SUNDAY NIGHT SKIES WILL CLEAR...WINDS WILL TURN TO THE WEST
NORTHWEST AND TEMPS WILL COOL DOWN INTO THE LOWER 40S BEHIND THE
COLD FRONT.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/... THE COLD FRONT WILL MOVE EAST
OF THE FORECAST AREA SUNDAY NIGHT...ALLOWING HIGH PRESSURE TO ONCE
AGAIN BUILD BACK INTO THE REGION FOR THE EARLY PART OF NEXT WEEK.
MODELS BRING ANOTHER STRONG ARCTIC HIGH DOWN INTO THE CENTRAL
PLAINS BY THE MIDDLE OF NEXT WEEK...WHICH WOULD BRING A DRY COLD
FRONT INTO THE REGION ALONG WITH COLDER TEMPERATURES. SO AT THIS
TIME IT LOOKS TO BE DRY FOR THE MONDAY THROUGH THURSDAY PERIOD
WITH BELOW NORMAL TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS EXPECTED THROUGH MUCH OF THE PERIOD...WITH
DIMINISHING CONDITIONS AFTER 06Z.
VFR CONDITIONS TO START THE FORECAST PERIOD WITH GENERALLY OVERCAST
MID LEVEL CLOUDS BUT COULD SEE SOME LOWER VFR CEILINGS IN PATCHES OF
RAIN THAT WILL BE MOVING INTO THE AREA FROM THE WEST...ASSOCIATED
WITH WEAK ISENTROPIC LIFT. LIGHT AND VARIABLE WINDS THROUGHOUT THE
FORECAST PERIOD ALTHOUGH A GENERAL PREVAILING NORTHEASTERLY
DIRECTION IS EXPECTED LATE TONIGHT INTO SATURDAY MORNING AS A COLD
AIR DAMMING WEDGE DEVELOPS. AS THE WEDGE DEVELOPS LATE
TONIGHT...CEILINGS ARE EXPECTED TO DROP INTO MVFR RANGE AFTER 06Z
THEN FALL INTO IFR CATEGORY AFTER AROUND 12Z FOR ALL TERMINALS.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS FOR BOTH CEILINGS AND
VISIBILITIES EXPECTED SATURDAY AFTERNOON AND NIGHT IN THE WEDGE THEN
SOME IMPROVEMENT EXPECTED ON SUNDAY. MORE RESTRICTIONS POSSIBLE WITH
A COLD FRONT SUNDAY AFTERNOON/EVENING. THUNDERSTORMS MAY IMPACT TAF
SITES SUNDAY AFTERNOON.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
633 AM EST FRI JAN 2 2015
.SYNOPSIS...
MOISTURE WILL INCREASE ACROSS THE AREA TODAY AS A LOW PRESSURE
SYSTEM AND COLD FRONT APPROACHES THE REGION FROM THE WEST. CHANCE
OF RAIN THROUGH THE WEEKEND. COLD HIGH PRESSURE AND DRY
CONDITIONS WILL BUILD BACK INTO THE REGION SUNDAY NIGHT AND MONDAY
THROUGH MID-WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SURFACE HIGH PRESSURE CONTINUES TO BUILD INTO THE REGION WHILE
THE WATER VAPOR IMAGERY SHOWS A DEEP UPPER LEVEL LOW OVER THE DESERT
SOUTHWEST WITH GENERALLY WEST- SOUTHWESTERLY FLOW ALOFT ACROSS THE
SOUTHERN PART OF THE COUNTRY. PATCHY LIGHT RAIN MOVED THROUGH THE
SOUTHERN PORTION OF THE CWA DURING THE OVERNIGHT. RADAR AT 10Z
INDICATING MORE RAIN UPSTREAM IN EASTERN ALABAMA AND WESTERN
GEORGIA. LATEST HRRR AND RAP MODELS SUGGEST THIS RAIN WILL MOVE
INTO SOUTH CAROLINA AND EAST CENTRAL GEORGIA THIS MORNING. RAIN
APPEARS TO BE ASSOCIATED WITH WEAK SHORT WAVE TROUGH EMBEDDED IN
WEST-SOUTHWEST UPPER LEVEL FLOW AND WEAK ISENTROPIC LIFT FOCUSED
IN THAT REGION AT THE MOMENT. BASED ON LATEST HRRR RUN WILL RAISE
POPS CSRA/WESTERN MIDLANDS/PIEDMONT THIS MORNING. PRECIPITABLE
WATER REMAINS LOW BUT WILL SLOWLY INCREASE THROUGH THE DAY.
RAINFALL AMOUNTS SHOULD BE LIGHT. IN-SITU WEDGE LIKELY TO DEVELOP
LEANED MORE TOWARD LOCAL WEDGE AND ECMWF OUTPUT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
WEDGE APPEARS TO STRENGTHEN TONIGHT WITH SURFACE RIDGE CENTER IN
FAVORABLE LOCATION IN THE NORTHEASTERN STATES EXTENDING SOUTHWEST
ACROSS THE CAROLINAS. CONFIDENCE HIGHER FOR COOL TEMPERATURES
SATURDAY. LITTLE CHANCE MADE TO TEMPERATURE FORECAST FROM
PREVIOUS FORECAST...SHOULD BE COOLER THAN TODAY AND LEANED TOWARD
LOCAL WEDGE TEMPERATURE OUTPUT/PREVIOUS FORECAST OVER MOS. CHANCE
OF RAIN/DRIZZLE HIGHER AS 850MB SOUTH FLOW INCREASES TO 20 TO 30
KTS BY AFTERNOON. ISENTROPIC LIFT 295K-300K SURFACE APPEARS
MODERATELY STRONG IN THE CENTRAL AND NORTH MIDLANDS/CSRA IN THE
AFTERNOON...SO PREFER HIGHER POP GUIDANCE...ALTHOUGH QPF LOW.
WEDGE CONTINUES ON SATURDAY SO TEMPS NEARLY STEADY BELOW
GUIDANCE. SATURDAY NIGHT THE COLD FRONT APPROACHES RAPIDLY FROM
THE WEST AND WARMER MOIST AIR STARTS TO PUSH NORTH AHEAD OF THE
FRONT. MIN TEMPS WILL LIKELY OCCUR EARLY WITH TEMPS RISING
OVERNIGHT ESPECIALLY IN THE SOUTHERN PART OF THE AREA. HAVE POPS
SATURDAY AND SATURDAY NIGHT IN THE 40 TO 60 PERCENT RANGE. RAIN
MAY FOCUS TO THE NORTH AND WEST SATURDAY NIGHT WHERE MOISTURE
DEEPER. WEDGE EXPECTED TO SLOWLY ERODE OVERNIGHT AS WARM FRONT
MOVES INTO THE AREA. TEMPERATURES EXPECTED TO REMAIN STEADY OR
RISE TOWARD SUNDAY MORNING.
THE BEST CHANCE FOR ACTIVE WEATHER WILL BE ON SUNDAY AS A SURFACE
LOW LIFTS NORTHWARD THROUGH THE OHIO RIVER VALLEY AND A COLD FRONT
MOVES EASTWARD TOWARDS THE REGION. MODELS IN GOOD AGREEMENT
BRINGING THE SURFACE FRONT THROUGH THE REGION DURING THE DAY ON
SUNDAY. WITH A STRONG LOW-LEVEL JET MOVING ALONG THE FRONT DURING
THE DAY...AND WITH SOME LIMITED INSTABILITY DURING THE
AFTERNOON...THERE IS SOME POTENTIAL FOR THUNDER. WITH MODEL LI/S
AROUND -1 TO -2 AND STRONG SHEAR...WILL MONITOR POTENTIAL FOR HIGH
SHEAR LOW CAPE CONVECTION AS THE FRONT PUSHES THROUGH.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE COLD FRONT WILL MOVE EAST OF THE FORECAST AREA SUNDAY
NIGHT...ALLOWING HIGH PRESSURE TO ONCE AGAIN BUILD BACK INTO THE
REGION FOR THE EARLY PART OF NEXT WEEK. MODELS BRING ANOTHER
STRONG ARCTIC HIGH DOWN INTO THE CENTRAL PLAINS BY THE MIDDLE OF
NEXT WEEK...WHICH WOULD BRING A DRY COLD FRONT INTO THE REGION
ALONG WITH COLDER TEMPERATURES. SO AT THIS TIME IT LOOKS TO BE DRY
FOR THE MONDAY THROUGH THURSDAY PERIOD WITH BELOW NORMAL
TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS STILL EXPECTED THROUGH MUCH OF THE PERIOD...WITH
POSSIBLE RETURN TO MVFR AFTER 06Z.
REGIONAL RADARS CONTINUE TO SHOW SHOWERS ASSOCIATED WITH WEAK
SHORTWAVE ENERGY MOVING ACROSS CENTRAL GA THIS MORNING. HRRR MODEL
INDICATES THIS ACTIVITY WILL HOLD TOGETHER AND MOVE INTO THE CSRA BY
13Z...THEN INTO THE CENTRAL MIDLANDS BY 14Z. THERE MAY BE SLIGHT
TIMING DIFFERENCES...BUT WILL GO WITH TEMPO GROUP IN THE CSRA
BEGINNING AT 13Z FOR -RA...THEN AT MIDLANDS SITES AT 14Z. GO
PREDOMINANT -RA AFTER THOSE TIMES....LASTING UNTIL EARLY AFTERNOON.
EXPECTING CONDITIONS TO REMAIN VFR THROUGH THE DAY...EVEN WITH THE
LIGHT RAIN. THE RAIN MAY LAST LONGER INTO THE AFTERNOON...BUT
CONFIDENCE NOT HIGH ENOUGH TO CONTINUE WITH RAIN IN THE TAFS AT THIS
TIME. SOME OF THE MODELS BEGIN INDICATING THAT MVFR CONDITIONS MAY
BE ABLE TO DEVELOP AFTER MIDNIGHT...WHILE OTHERS STILL SHOWING VFR.
HAVE TRENDED TOWARDS LOW END VFR CONDITIONS FOR THE OVERNIGHT
HOURS...BUT THIS MAY CONTINUE TO TREND DOWNWARD INTO MVFR WITH LATER
FORECAST UPDATES. EXPECT LIGHT AND VARIABLE WINDS THROUGH THE
PERIOD.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS FOR BOTH CEILINGS AND
VISIBILITIES WILL BE POSSIBLE SATURDAY AND SUNDAY AHEAD OF THE NEXT
STORM SYSTEM. THUNDERSTORMS MAY IMPACT TAF SITES ON SUNDAY JUST
AHEAD OF THE MAIN SURFACE COLD FRONT.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
514 AM EST FRI JAN 2 2015
.SYNOPSIS...
MOISTURE WILL INCREASE ACROSS THE AREA TODAY AS A LOW PRESSURE
SYSTEM AND COLD FRONT APPROACHES THE REGION FROM THE WEST. CHANCE
OF RAIN THROUGH THE WEEKEND. COLD HIGH PRESSURE AND DRY
CONDITIONS WILL BUILD BACK INTO THE REGION SUNDAY NIGHT AND MONDAY
THROUGH MID-WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SURFACE HIGH PRESSURE CONTINUES TO BUILD INTO THE REGION WHILE
THE WATER VAPOR IMAGERY SHOWS A DEEP UPPER LEVEL LOW OVER THE DESERT
SOUTHWEST WITH GENERALLY WEST- SOUTHWESTERLY FLOW ALOFT ACROSS THE
SOUTHERN PART OF THE COUNTRY. PATCHY LIGHT RAIN MOVED THROUGH THE
SOUTHERN PORTION OF THE CWA DURING THE OVERNIGHT. RADAR AT 10Z
INDICATING MORE RAIN UPSTREAM IN EASTERN ALABAMA AND WESTERN
GEORGIA. LATEST HRRR AND RAP MODELS SUGGEST THIS RAIN WILL MOVE
INTO SOUTH CAROLINA AND EAST CENTRAL GEORGIA THIS MORNING. RAIN
APPEARS TO BE ASSOCIATED WITH WEAK SHORT WAVE TROUGH EMBEDDED IN
WEST-SOUTHWEST UPPER LEVEL FLOW AND WEAK ISENTROPIC LIFT FOCUSED
IN THAT REGION AT THE MOMENT. BASED ON LATEST HRRR RUN WILL RAISE
POPS CSRA/WESTERN MIDLANDS/PIEDMONT THIS MORNING. PRECIPITABLE
WATER REMAINS LOW BUT WILL SLOWLY INCREASE THROUGH THE DAY.
RAINFALL AMOUNTS SHOULD BE LIGHT. IN-SITU WEDGE LIKELY TO DEVELOP
LEANED MORE TOWARD LOCAL WEDGE AND ECMWF OUTPUT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
WEDGE APPEARS TO STRENGTHEN TONIGHT WITH SURFACE RIDGE CENTER IN
FAVORABLE LOCATION IN THE NORTHEASTERN STATES EXTENDING SOUTHWEST
ACROSS THE CAROLINAS. CONFIDENCE HIGHER FOR COOL TEMPERATURES
SATURDAY. LITTLE CHANCE MADE TO TEMPERATURE FORECAST FROM
PREVIOUS FORECAST...SHOULD BE COOLER THAN TODAY AND LEANED TOWARD
LOCAL WEDGE TEMPERATURE OUTPUT/PREVIOUS FORECAST OVER MOS. CHANCE
OF RAIN/DRIZZLE HIGHER AS 850MB SOUTH FLOW INCREASES TO 20 TO 30
KTS BY AFTERNOON. ISENTROPIC LIFT 295K-300K SURFACE APPEARS
MODERATELY STRONG IN THE CENTRAL AND NORTH MIDLANDS/CSRA IN THE
AFTERNOON...SO PREFER HIGHER POP GUIDANCE...ALTHOUGH QPF LOW.
WEDGE CONTINUES ON SATURDAY SO TEMPS NEARLY STEADY BELOW
GUIDANCE. SATURDAY NIGHT THE COLD FRONT APPROACHES RAPIDLY FROM
THE WEST AND WARMER MOIST AIR STARTS TO PUSH NORTH AHEAD OF THE
FRONT. MIN TEMPS WILL LIKELY OCCUR EARLY WITH TEMPS RISING
OVERNIGHT ESPECIALLY IN THE SOUTHERN PART OF THE AREA. HAVE POPS
SATURDAY AND SATURDAY NIGHT IN THE 40 TO 60 PERCENT RANGE. RAIN
MAY FOCUS TO THE NORTH AND WEST SATURDAY NIGHT WHERE MOISTURE
DEEPER. WEDGE EXPECTED TO SLOWLY ERODE OVERNIGHT AS WARM FRONT
MOVES INTO THE AREA. TEMPERATURES EXPECTED TO REMAIN STEADY OR
RISE TOWARD SUNDAY MORNING.
THE BEST CHANCE FOR ACTIVE WEATHER WILL BE ON SUNDAY AS A SURFACE
LOW LIFTS NORTHWARD THROUGH THE OHIO RIVER VALLEY AND A COLD FRONT
MOVES EASTWARD TOWARDS THE REGION. MODELS IN GOOD AGREEMENT
BRINGING THE SURFACE FRONT THROUGH THE REGION DURING THE DAY ON
SUNDAY. WITH A STRONG LOW-LEVEL JET MOVING ALONG THE FRONT DURING
THE DAY...AND WITH SOME LIMITED INSTABILITY DURING THE
AFTERNOON...THERE IS SOME POTENTIAL FOR THUNDER. WITH MODEL LI/S
AROUND -1 TO -2 AND STRONG SHEAR...WILL MONITOR POTENTIAL FOR HIGH
SHEAR LOW CAPE CONVECTION AS THE FRONT PUSHES THROUGH.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE COLD FRONT WILL MOVE EAST OF THE FORECAST AREA SUNDAY
NIGHT...ALLOWING HIGH PRESSURE TO ONCE AGAIN BUILD BACK INTO THE
REGION FOR THE EARLY PART OF NEXT WEEK. MODELS BRING ANOTHER
STRONG ARCTIC HIGH DOWN INTO THE CENTRAL PLAINS BY THE MIDDLE OF
NEXT WEEK...WHICH WOULD BRING A DRY COLD FRONT INTO THE REGION
ALONG WITH COLDER TEMPERATURES. SO AT THIS TIME IT LOOKS TO BE DRY
FOR THE MONDAY THROUGH THURSDAY PERIOD WITH BELOW NORMAL
TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS STILL EXPECTED THROUGH THE PERIOD.
REGIONAL RADARS SHOWING LIGHT RAINFALL MOVING EAST OF THE CSRA AND
CENTRAL MIDLANDS. SHOULD SEE A BREAK IN THE LIGHT RAIN OVER THE
NEXT SEVERAL HOURS. CEILINGS TO REMAIN VFR WITH HEIGHTS AROUND
10KFT. WITH PLENTY OF CLOUD COVER...DO NOT ANTICIPATE ANY FOG
FORMATION DURING THE MORNING. THROUGH THE DAY FRIDAY CEILINGS WILL
TREND SLOWLY DOWNWARD...BUT STILL REMAINING VFR. EXPECT LIGHT AND
VARIABLE WINDS THROUGH THE PERIOD. MAY SEE ADDITIONAL LIGHT
RAINFALL LATE IN THE DAYTIME PERIOD AND INTO PORTIONS OF THE
OVERNIGHT...HOWEVER TIMING AND LOW CONFIDENCE PRECLUDE MENTION IN
THE TAFS AT THIS TIME.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS FOR BOTH CEILINGS AND
VISIBILITIES WILL BE POSSIBLE LATE FRIDAY NIGHT AND THROUGH THE
WEEKEND WITH NEXT STORM SYSTEM APPROACHING.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
609 AM EST FRI JAN 2 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 348 AM EST FRI JAN 2 2015
A LOW PRESSURE SYSTEM APPROACHING FROM THE PLAINS WILL BRING A
CHANCE FOR SOME LIGHT FREEZING RAIN AND RAIN TO THE AREA TONIGHT AND
MODERATE TO HEAVY RAIN AT TIMES ON SATURDAY. COULD SEE A CHANCE FOR
SNOW ON SUNDAY AS THE SYSTEM MOVES OUT AND COLDER AIR ARRIVES. A
CLIPPER SYSTEM WILL BRING LIGHT SNOW CHANCES MONDAY NIGHT THROUGH
TUESDAY AND COLDER AIR WILL SETTLE IN OVER THE AREA.
&&
.NEAR TERM /THIS MORNING AND TODAY/...
ISSUED AT 348 AM EST FRI JAN 2 2015
RADAR LOOP AND OBSERVATIONS ARE SHOWING SOME LIGHT SNOW AND RAIN
ACROSS SOUTHERN PORTIONS OF CENTRAL INDIANA. HRRR AND RAP SHOW THESE
LIGHT SHOWERS CONTINUING OFF AND ON THROUGH AROUND 12-15Z SO ADDED
SOME LOW CHANCE POPS INTO THE SOUTH TO COVER THESE FOR THE NEXT FEW
HOURS. COULD SEE SOME VERY LIGHT SLEET AS WELL IN THIS WINTRY
MIX...AND THIS COMBINATION COULD CAUSE SOME SLICK SPOTS ON UNTREATED
ROADS IN SOUTHERN PARTS OF CENTRAL INDIANA EARLY THIS MORNING.
AFTER THE AFOREMENTIONED SHOWERS MOVE OFF TO THE EAST SHOULD SEE DRY
CONDITIONS ACROSS THE AREA FOR THE REST OF THE DAY. CLOUDS WILL
CONTINUE TO STREAM IN FROM THE SOUTH OVERRUNNING THE WARM FRONT AND
THIS SHOULD KEEP TEMPERATURES FROM RISING TOO SIGNIFICANTLY TODAY.
SHOULD SEE HIGHS MAINLY IN THE 30S.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
ISSUED AT 348 AM EST FRI JAN 2 2015
FORECAST FOCUS IS ON PRECIP TIMING WITH WEEKEND SYSTEM AS WELL AS
PRECIP TYPE. MODELS ARE IN FAIRLY GOOD AGREEMENT AND WILL USE A
CONSENSUS APPROACH FOR THE MOST PART.
TO BEGIN THE TONIGHT PERIOD LOOKS LIKE A WARM FRONT WILL BE
APPROACHING FROM THE SOUTH AS A LOW PRESSURE SYSTEM PREPARES TO
TRAVEL THROUGH THE OHIO VALLEY FROM THE PLAINS. PRECIPITATION WILL
MOVE IN FROM THE SOUTHWEST. THIS SET OF MODEL RUNS IS FASTER WITH
THE APPROACH OF THE SYSTEM SO TRENDED THAT WAY AND BROUGHT IN POPS
AFTER 3Z. THICKNESSES AND SOUNDINGS INDICATE THE POTENTIAL FOR
FREEZING RAIN FOR A PERIOD AT ONSET...BUT THE WARM ADVECTION LOOKS
STOUT AND MODELS ARE ALL PROGGING SURFACE TEMPERATURES TO START
RISING BETWEEN 3 AND 9Z. WITH SURFACE TEMPERATURES POSSIBLY WARMING
ABOVE FREEZING DURING THE OVERNIGHT INCLUDED CHANCES FOR FREEZING
RAIN ALONG WITH THE RAIN BUT ELIMINATED THE FREEZING RAIN FROM SOUTH
TO NORTH STILL DURING THE TONIGHT PERIOD BASED ON HOURLY SURFACE
TEMPERATURES SURPASSING FREEZING. STILL MAINTAINED A CHANCE FOR
FREEZING RAIN IN THE NORTHERN COUNTIES FROM 12-15Z SATURDAY IN CASE
SURFACE TEMPERATURES DO NOT RISE AS QUICKLY AS ANTICIPATED.
SATURDAY STRONG ISENTROPIC LIFT ALONG WITH UPPER FORCING AND FORCING
FROM THE APPROACH AND PASSAGE OF THE SURFACE LOW WILL BRING RAIN TO
THE ENTIRE AREA. A STRONG LOW LEVEL JET WILL BRING AMPLE MOISTURE
UP AHEAD OF THE SYSTEM AND COULD SEE RAINFALL TOTALS IN EXCESS OF
1.5-2 INCHES IN SOME PLACES. RAIN SHOULD CONTINUE INTO SATURDAY
NIGHT AND COULD SEE SOME SNOW MIX IN LATE IN THE NORTHWEST.
UPPER SHORTWAVE WILL MOVE THROUGH THE AREA ON SUNDAY. ALTHOUGH THE
ATMOSPHERE SHOULD BE PRETTY DRY...WITH THE WAVE MOVING THROUGH ALONG
WITH MUCH COLDER AIR COMING INTO PLACE THING SEEING SOME SNOW IS NOT
OUT OF THE QUESTION. THUS WENT WITH CONSENSUS LOW CHANCE POPS IN THE
NORTHWEST CLOSER TO THE TRACK OF THE SHORTWAVE TAPERING TO SLIGHT
CHANCE IN THE SOUTHWEST. COLUMN SHOULD BE COOL ENOUGH FOR ANY PRECIP
SUNDAY TO FALL AS SNOW. BY SUNDAY NIGHT THE UPPER WAVE WILL BE
THROUGH AND SHOULD SEE DRY CONDITIONS. COLD ADVECTION ON DECENT
NORTHWESTERLY WINDS SHOULD ALLOW TEMPERATURES TO DROP BUT THE MIXING
FROM THE WIND SHOULD KEEP THEM FROM BOTTOMING OUT. THUS ACCEPTED THE
SLIGHTLY WARMER CONSENSUS NUMBERS WITH SINGLE DIGITS NORTHWEST TO
MID TEENS SOUTHEAST.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
ISSUED AT 348 AM EST FRI JAN 2 2015
APPEARS THE MAJORITY OF THE EXTENDED PERIOD WILL BE DRY...SAVE FOR
ONE QUICK CLIPPER SYSTEM SET TO IMPACT THE AREA MONDAY NIGHT THROUGH
TUESDAY. ANYWHERE FROM HALF AN INCH TO UPWARDS OF NEAR AN INCH OF
SNOW IS POSSIBLE AT THIS TIME...SO ACCUMULATIONS LOOK LIGHT AT THIS
TIME.
THE OTHER BIGGER STORY DURING THIS TIME IS POTENTIALLY THE
COLDEST AIR OF THE SEASON BEARING DOWN ON THE REGION AFTER THAT
CLIPPER SYSTEM EXITS THE REGION. BY TUESDAY NIGHT ALREADY LOOKING AT
SINGLE DIGIT TEMPS...SAME FOR WEDNESDAY NIGHT. THESE VERY COLD TEMPS
COMBINED WITH STRONG SURFACE N/NW FLOW WILL CREATE WIND CHILLS THAT
MAY APPROACH WIND CHILL ADVISORY CRITERIA AT TIMES TUESDAY NIGHT
THROUGH THURSDAY.
&&
.AVIATION /DISCUSSION FOR THE 021200Z TAF ISSUANCE/...
ISSUED AT 605 AM EST FRI JAN 2 2015
VFR EXPECTED AT LEAST THROUGH THE BULK OF THE DAY. AFTER 20Z AT
HUF AND BMG AND 00Z SAT AT IND...COULD SEE CONDITIONS DETERIORATE
TO MVFR OR WORSE AS CU EXPANDS NORTHWARD ACROSS THE TERMINALS IN
SOUTHERLY FLOW AHEAD OF A SOUTHERN SYSTEM. WINDS SHOULD BE
SOUTHWEST LESS THAN 10 KNOTS UNTIL AFTER 18Z WHEN WINDS WILL BACK
TO SOUTH AND THEN SOUTHEAST. THEN EITHER -FZRA OR A MIXTURE WITH
RAIN WILL MOVE INTO SOUTH CENTRAL INDIANA AFTER MIDNIGHT...MIX FOR
A FEW HOURS OVER ALL OF THE TAF SITES EARLY SATURDAY MORNING
BEFORE CHANGING OVER TO A MODERATE RAIN AND DROPPING TO IFR LATE
IN THE PERIOD. BEFORE THE DROP TO IFR...EXPECT MFVR CONDITIONS
BEFORE THE ARRIVAL OF PRECIP WITH LOW STRATO CU AND WITH THE -FZRA
MIX.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM....SMF
AVIATION...SMF
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
352 AM EST FRI JAN 2 2015
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM
AND LONG TERM SECTIONS HAVE BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 348 AM EST FRI JAN 2 2015
A LOW PRESSURE SYSTEM APPROACHING FROM THE PLAINS WILL BRING A
CHANCE FOR SOME LIGHT FREEZING RAIN AND RAIN TO THE AREA TONIGHT AND
MODERATE TO HEAVY RAIN AT TIMES ON SATURDAY. COULD SEE A CHANCE FOR
SNOW ON SUNDAY AS THE SYSTEM MOVES OUT AND COLDER AIR ARRIVES. A
CLIPPER SYSTEM WILL BRING LIGHT SNOW CHANCES MONDAY NIGHT THROUGH
TUESDAY AND COLDER AIR WILL SETTLE IN OVER THE AREA.
&&
.NEAR TERM /THIS MORNING AND TODAY/...
ISSUED AT 348 AM EST FRI JAN 2 2015
RADAR LOOP AND OBSERVATIONS ARE SHOWING SOME LIGHT SNOW AND RAIN
ACROSS SOUTHERN PORTIONS OF CENTRAL INDIANA. HRRR AND RAP SHOW THESE
LIGHT SHOWERS CONTINUING OFF AND ON THROUGH AROUND 12-15Z SO ADDED
SOME LOW CHANCE POPS INTO THE SOUTH TO COVER THESE FOR THE NEXT FEW
HOURS. COULD SEE SOME VERY LIGHT SLEET AS WELL IN THIS WINTRY
MIX...AND THIS COMBINATION COULD CAUSE SOME SLICK SPOTS ON UNTREATED
ROADS IN SOUTHERN PARTS OF CENTRAL INDIANA EARLY THIS MORNING.
AFTER THE AFOREMENTIONED SHOWERS MOVE OFF TO THE EAST SHOULD SEE DRY
CONDITIONS ACROSS THE AREA FOR THE REST OF THE DAY. CLOUDS WILL
CONTINUE TO STREAM IN FROM THE SOUTH OVERRUNNING THE WARM FRONT AND
THIS SHOULD KEEP TEMPERATURES FROM RISING TOO SIGNIFICANTLY TODAY.
SHOULD SEE HIGHS MAINLY IN THE 30S.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
ISSUED AT 348 AM EST FRI JAN 2 2015
FORECAST FOCUS IS ON PRECIP TIMING WITH WEEKEND SYSTEM AS WELL AS
PRECIP TYPE. MODELS ARE IN FAIRLY GOOD AGREEMENT AND WILL USE A
CONSENSUS APPROACH FOR THE MOST PART.
TO BEGIN THE TONIGHT PERIOD LOOKS LIKE A WARM FRONT WILL BE
APPROACHING FROM THE SOUTH AS A LOW PRESSURE SYSTEM PREPARES TO
TRAVEL THROUGH THE OHIO VALLEY FROM THE PLAINS. PRECIPITATION WILL
MOVE IN FROM THE SOUTHWEST. THIS SET OF MODEL RUNS IS FASTER WITH
THE APPROACH OF THE SYSTEM SO TRENDED THAT WAY AND BROUGHT IN POPS
AFTER 3Z. THICKNESSES AND SOUNDINGS INDICATE THE POTENTIAL FOR
FREEZING RAIN FOR A PERIOD AT ONSET...BUT THE WARM ADVECTION LOOKS
STOUT AND MODELS ARE ALL PROGGING SURFACE TEMPERATURES TO START
RISING BETWEEN 3 AND 9Z. WITH SURFACE TEMPERATURES POSSIBLY WARMING
ABOVE FREEZING DURING THE OVERNIGHT INCLUDED CHANCES FOR FREEZING
RAIN ALONG WITH THE RAIN BUT ELIMINATED THE FREEZING RAIN FROM SOUTH
TO NORTH STILL DURING THE TONIGHT PERIOD BASED ON HOURLY SURFACE
TEMPERATURES SURPASSING FREEZING. STILL MAINTAINED A CHANCE FOR
FREEZING RAIN IN THE NORTHERN COUNTIES FROM 12-15Z SATURDAY IN CASE
SURFACE TEMPERATURES DO NOT RISE AS QUICKLY AS ANTICIPATED.
SATURDAY STRONG ISENTROPIC LIFT ALONG WITH UPPER FORCING AND FORCING
FROM THE APPROACH AND PASSAGE OF THE SURFACE LOW WILL BRING RAIN TO
THE ENTIRE AREA. A STRONG LOW LEVEL JET WILL BRING AMPLE MOISTURE
UP AHEAD OF THE SYSTEM AND COULD SEE RAINFALL TOTALS IN EXCESS OF
1.5-2 INCHES IN SOME PLACES. RAIN SHOULD CONTINUE INTO SATURDAY
NIGHT AND COULD SEE SOME SNOW MIX IN LATE IN THE NORTHWEST.
UPPER SHORTWAVE WILL MOVE THROUGH THE AREA ON SUNDAY. ALTHOUGH THE
ATMOSPHERE SHOULD BE PRETTY DRY...WITH THE WAVE MOVING THROUGH ALONG
WITH MUCH COLDER AIR COMING INTO PLACE THING SEEING SOME SNOW IS NOT
OUT OF THE QUESTION. THUS WENT WITH CONSENSUS LOW CHANCE POPS IN THE
NORTHWEST CLOSER TO THE TRACK OF THE SHORTWAVE TAPERING TO SLIGHT
CHANCE IN THE SOUTHWEST. COLUMN SHOULD BE COOL ENOUGH FOR ANY PRECIP
SUNDAY TO FALL AS SNOW. BY SUNDAY NIGHT THE UPPER WAVE WILL BE
THROUGH AND SHOULD SEE DRY CONDITIONS. COLD ADVECTION ON DECENT
NORTHWESTERLY WINDS SHOULD ALLOW TEMPERATURES TO DROP BUT THE MIXING
FROM THE WIND SHOULD KEEP THEM FROM BOTTOMING OUT. THUS ACCEPTED THE
SLIGHTLY WARMER CONSENSUS NUMBERS WITH SINGLE DIGITS NORTHWEST TO
MID TEENS SOUTHEAST.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
ISSUED AT 348 AM EST FRI JAN 2 2015
APPEARS THE MAJORITY OF THE EXTENDED PERIOD WILL BE DRY...SAVE FOR
ONE QUICK CLIPPER SYSTEM SET TO IMPACT THE AREA MONDAY NIGHT THROUGH
TUESDAY. ANYWHERE FROM HALF AN INCH TO UPWARDS OF NEAR AN INCH OF
SNOW IS POSSIBLE AT THIS TIME...SO ACCUMULATIONS LOOK LIGHT AT THIS
TIME.
THE OTHER BIGGER STORY DURING THIS TIME IS POTENTIALLY THE
COLDEST AIR OF THE SEASON BEARING DOWN ON THE REGION AFTER THAT
CLIPPER SYSTEM EXITS THE REGION. BY TUESDAY NIGHT ALREADY LOOKING AT
SINGLE DIGIT TEMPS...SAME FOR WEDNESDAY NIGHT. THESE VERY COLD TEMPS
COMBINED WITH STRONG SURFACE N/NW FLOW WILL CREATE WIND CHILLS THAT
MAY APPROACH WIND CHILL ADVISORY CRITERIA AT TIMES TUESDAY NIGHT
THROUGH THURSDAY.
&&
.AVIATION /DISCUSSION FOR THE 020600Z TAF ISSUANCE/...
ISSUED AT 318 AM EST FRI JAN 2 2015
0815Z UPDATE...NO CHANGES NEEDED AT THIS TIME. PREVIOUS DISCUSSION
FOLLOWS.
VFR EXPECTED AT LEAST THROUGH THE BULK OF THE DAY TOMORROW. AFTER
20Z AT HUF AND BMG AND 00Z SATURDAY AT IND...COULD SEE CONDITIONS
DETERIORATE TO MVFR OR WORSE AS CU EXPANDS NORTHWARD ACROSS THE
TERMINALS IN SOUTHERLY FLOW AHEAD OF A SOUTHERN SYSTEM.
WINDS SHOULD BE SOUTHWEST LESS THAN 10 KNOTS UNTIL AFTER 18Z WHEN
WINDS WILL BACK TO SOUTH AND THEN SOUTHEAST.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM....SMF
AVIATION...SMF/KOCH
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AREA FORECAST DISCUSSION
NWS JACKSON KY
909 PM EST SAT JAN 3 2015
.UPDATE...
ISSUED AT 909 PM EST SAT JAN 3 2015
UPDATED THE FORECAST TO REMOVE THUNDER. ALL THE LIGHTNING AS BEEN
BOTTLED UP WELL TO OUR SOUTH AND BASED ON TRAJECTORIES...IT JUST
WON`T MAKE IT THIS FAR NORTH. WITH THIS SAID...HEAVIER RAIN THREAT
SEEMS TO BE DIMINISHING AS HRRR AND RAP ARE SHOWING A FASTER
PROGRESSION OF THE PRECIPITATION THROUGH THE AREA OVERNIGHT. IN
FACT...IT LOOKS LIKE RAIN COULD BE MOVING OUT AS EARLY AS 4 OR 5 AM.
WITH RAINFALL RATES AT BEST AROUND A QUARTER OF AN INCH PER
HOUR...REALLY DON`T SEE MUCH OF A HEAVY RAIN THREAT REMAINING. THE
WIND THREAT REMAINS FOR THE HIGHER ELEVATIONS AS VAD WIND PROFILE
CONTINUES TO SHOW 35 TO 40 MPH WINDS JUST OFF THE SURFACE.
UPDATE ISSUED AT 712 PM EST SAT JAN 3 2015
COLD FRONT HAS NOW CROSSED WESTERN KENTUCKY. AMPLE MOISTURE IS
PUSHING NORTHWARD AHEAD OF THE FRONT OVER THE LOWER MISSISSIPPI RIVER
VALLEY. THIS RAIN IS EXPECTED TO OVERSPREAD EASTERN KENTUCKY OVER THE
NEXT 2 TO 4 HOURS. VERY COLD CLOUD TOPS ASSOCIATED WITH THIS ACTIVITY
WILL KEEP THE THREAT OF THUNDER IN THE FORECAST THROUGH THIS EVENING.
HOWEVER...LATEST HI-RES MODEL GUIDANCE SUGGEST THE THUNDER THREAT
MAY EXIT AROUND MIDNIGHT AS THE FRONT SLOWS OVER THE AREA.
HOWEVER...RAIN WILL LIKELY PERSIST THROUGH THE NIGHT...BEFORE
TAPERING OFF FROM WEST TO EAST TOWARDS DAYBREAK. PRECIPITABLE WATER
REMAIN AROUND 1.4 TONIGHT WHICH IS NEAR THE 99TH PERCENTILE FOR EARLY
JANUARY. THIS WILL KEEP THE THREAT OF LOCALLY HEAVY RAIN IN THE
FORECAST OVERNIGHT. NOT TOO CONCERNED ABOUT THE 1 HOUR FLASH FLOOD
GUIDANCE AS WE WON`T LIKELY SEE THIS KIND OF RAINFALL TONIGHT.
HOWEVER...THE 3 HOUR FLASH FLOOD GUIDANCE IS JUST UNDER 2 INCHES IN
SOME PLACES...SO WE WILL HAVE TO WATCH FOR SOME MINOR FLOODING
POTENTIAL TONIGHT. CERTAINLY PONDING ON ROADS WILL BE AN ISSUE DUE TO
THE HEAVY NATURE OF THE RAIN. ADJUSTED POPS AND WEATHER TO ALLOW FOR
A BRIEF LULL BEFORE THE RAIN ARRIVES THIS EVENING. ALSO ADJUSTED
TEMPERATURES TO SHOW A STEADY TEMPERATURE CURVE THROUGH THE NIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 332 PM EST SAT JAN 3 2015
AN UPPER LEVEL LOW...CURRENTLY OVER THE NORTH TEXAS PANHANDLE...WILL
CONTINUE TO SHIFT NE THIS EVENING AND OVERNIGHT...GRAZING THE
WESTERN PORTION OF THE STATE BEFORE MERGING INTO THE NORTHERN STREAM
AND LOSING CONSIDERABLE STRENGTH. MEANWHILE...MUCH OF KY WILL
EXPERIENCE STRONG SW TO NE FLOW THROUGH THE DAY SUNDAY...AS LONGWAVE
TROUGHING TAKES HOLD ACROSS MUCH OF THE CENTRAL CONUS. THE AXIS OF
THIS TROUGH IS EXPECTED TO REACH EASTERN KY BY SUNDAY
EVENING...WHERE IT WILL REMAIN STATIONARY THROUGH SUNDAY NIGHT WITH
IMPRESSIVELY STRONG PRESSURE GRADIENTS EXPECTED ACROSS THE OHIO
RIVER AND TENNESSEE VALLEY REGIONS.
CURRENTLY...A WARM FRONT HAS JUST PASSED FROM NORTH TO SOUTH ACROSS
MUCH OF KY...EXTENDING FROM A SURFACE LOW PRESSURE SYSTEM WHICH IS
SITTING OVER SOUTHERN ILLINOIS. THIS HAS ALLOWED VERY UNSEASONABLY
WARM TEMPERATURES TO FLOW INTO THE CWA...SUCH AS 64 DEGREES HERE AT
THE NWS OFFICE...67 AT QUICKSAND...AND 68 DEGREES AT WHITESBURG. THE
STRONG LOW LEVEL INVERSION THAT WAS IN PLACE JUST AHEAD OF THIS WARM
FRONT /AS STRONG OVERRUNNING WAS TAKING PLACE EARLIER IN THE DAY/ IS
NOW STARTING TO SUBSIDE...THUS ALLOWING STRONG SSW WINDS TO BEGIN
REACHING THE GROUND. PRECIP IS ALSO CONTINUING TO FILTER INTO THE
REGION FROM THE SW...CURRENTLY SCT TO WIDESPREAD RAIN IS FALLING
ACROSS THE REGION. WE HAVE HAD A FEW LIGHTNING STRIKES WITH THE
CONVECTION LATE THIS MORNING...SO KEPT MENTION OF THUNDER GOING IN
THE FORECAST FOR THE DAY. EXPECT ANY HEAVY SHOWERS TO RESULT IN WIND
GUSTS BETWEEN 20 AND 30MPH THROUGH THE REST OF THE AFTERNOON.
IN ADDITION TO ALL OF THIS...A COLD FRONT IS CURRENTLY EXTENDING
SOUTHWARD FROM THE LOW...JUST WEST OF KY. AS THE SURFACE LOW
CONTINUES TO LIFT TO THE NE THIS EVENING AND OVERNIGHT...THIS COLD
FRONT WILL SLOWLY PROGRESS EASTWARD. THE LATEST GFS40 MODEL IS
PROJECTING THE PASSAGE OF THE FRONT ACROSS EASTERN KY BETWEEN 6Z
/WEST/ AND 12Z /EAST/ OVERNIGHT TONIGHT. IT IS ALONG AND JUST AHEAD
OF THIS COLD FRONT THAT THE HEAVIEST RAIN AND ISOLATED THUNDERSTORMS
ARE ONGOING...CURRENTLY SPANNING FROM MEMPHIS TO WESTERN OHIO. THIS
CONVECTION WILL MAKE IT/S WAY INTO OUR CWA AND MOVE FROM WEST TO
EAST THIS EVENING AND THROUGH THE OVERNIGHT HOURS TONIGHT. GIVEN THE
WIDESPREAD CLOUD COVER AND PRECIP THAT WILL LIKELY OCCUR...WENT MUCH
HIGHER THAN THE MOS FOR OVERNIGHT LOW TEMPERATURES. WOULDN/T BE
SURPRISED IF WE STAY WELL IN THE 50S FOR LOWS. MODELS ARE STILL IN
GOOD AGREEMENT AND SHOW GOOD CONSISTENCY...SO NO DRASTIC CHANGES
WERE MADE TO THE PREVIOUS FORECAST FOR TIMING AND PRECIP AMOUNTS AS
THE PREFRONTAL/FRONTAL PRECIP MOVES THROUGH THE AREA TONIGHT. KEPT
OVERNIGHT QPF BETWEEN AN INCH AND AN INCH AND A QUARTER AT MOST
LOCATIONS.
STRONG WINDS ALOFT AS A RESULT OF THE TIGHT PRESSURE GRADIENTS WILL
CONTINUE TO MIX DOWN WITH ANY OF THE HEAVIER SHOWERS/THUNDERSTORMS
THIS AFTERNOON AND EVENING. EXPECT THESE WINDS TO INCREASE ALONG AND
JUST BEHIND THE COLD FRONT. ONCE THE COLD FRONT PASSES THROUGH...AN
IMPRESSIVE BLAST OF DRY AIR WILL QUICKLY MOVE INTO THE REGION WITH
WINDS SHIFTING TO A MORE WRLY DIRECTION. ALTHOUGH SOME WRAP AROUND
MOISTURE WILL BE POSSIBLE WITH THIS SYSTEM DURING THE DAY
SUNDAY...QPF AMOUNTS WILL BE DRASTICALLY REDUCED WITH ANY PRECIP
THAT DOES OCCUR. COLDER AIR FILTERING INTO THE REGION BEHIND THE
COLD FRONT WILL KEEP TEMPERATURES FALLING THROUGHOUT THE DAY SUNDAY.
BY SUNDAY NIGHT...TEMPS WILL DROP WELL BELOW FREEZING. THEREFORE...IT
IS POSSIBLE THAT SOME SNOW MAY MIX WITH THE RAIN AS IT TAPERS OFF
SUNDAY NIGHT. ANY REMAINING SHALLOW MOISTURE WILL BE CAUGHT IN AN
UPSLOPE FLOW PATTERN LATE SUNDAY NIGHT...WITH TEMPS FALLING TO -10C
OR LOWER ACCORDING TO THE LATEST FORECAST SOUNDINGS. AS
SUCH...CONTINUED MENTION OF FLURRIES IN THE SE SUNDAY
NIGHT...EXPANDING IN COVERAGE AS TEMPERATURES CONTINUE TO FALL BELOW
-10C ALOFT.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 428 AM EST SAT JAN 3 2015
THE MODELS ARE IN REASONABLE AGREEMENT UNTIL LATE IN THE PERIOD. THE
MAIN ISSUE WILL BE A COUPLE OF SURGES OF COLD AIR...ALTHOUGH A BIT
OF LIGHT PRECIP CAN NOT BE RULED OUT. THE COLDEST PART OF THE FIRST
SURGE WILL BE MOVING INTO THE REGION ON MONDAY. WITH UPSLOPE FLOW
AND FORECAST SOUNDINGS SHOWING A SHALLOW MIXED LAYER WITH SATURATION
REACHING TO -10C...A FEW LINGERING FLURRIES WILL BE POSSIBLE EARLY
MONDAY. A CLIPPER TYPE SYSTEM CARRIED ALONG BY RAPID FLOW ALOFT IS
EXPECTED TO PASS NORTH OF THE OHIO RIVER ON TUESDAY. PRECIP WITH
THIS IS LIKELY TO STAY TO OUR NORTH...BUT WITH THE CLOSE PROXIMITY
AND AN ALLOWABLE MARGIN OF ERROR...HAVE CARRIED A SLIGHT CHANCE OF
SNOW IN OUR EXTREME NORTH. THE PASSAGE OF THIS SYSTEM WILL MAKE WAY
FOR THE SECOND SURGE OF COLD AIR...THE COLDEST OF THE SEASON SO FAR.
THE ONSLAUGHT BEGINS BY TUESDAY NIGHT AND CONTINUES INTO WEDNESDAY
NIGHT. THE COLD AIR ADVECTION SHOULD RESULT IN FALLING TEMPS DURING
THE DAY WEDNESDAY. BY THURSDAY MORNING...READINGS SHOULD BE NEAR
ZERO...WITH COLDER VALLEYS PROBABLY BELOW ZERO. DESPITE SOME
SUNSHINE ON THURSDAY...ONLY A LIMITED RECOVERY IS FORECAST IN THE
ARCTIC AIR MASS...WITH SOME LOCATIONS NOT GETTING OUT OF THE TEENS.
IT WILL STILL BE VERY COLD ON THURSDAY NIGHT...BUT NOT AS EXTREME AS
WARM AIR ADVECTION GETS UNDERWAY. THE ECMWF AND GFS START TO SHOW
SIGNIFICANT DIFFERENCES BY NEXT SATURDAY AS A MID/UPPER LEVEL WAVE
DROPS ESE INTO THE CONUS. THE GFS DEVELOPS A SURFACE SYSTEM WHICH
MOVES IN FROM THE WEST WITH LIGHT PRECIP... WHILE THE ECMWF SHOWS
LITTLE SURFACE DEVELOPMENT. IT IS A LOW CONFIDENCE FORECAST BY NEXT
WEEKEND...AND HAVE CARRIED SLIGHT CHANCE POPS ON SATURDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 712 PM EST SAT JAN 3 2015
A STRONG COLD FRONT WILL PUSH EAST ACROSS THE AREA TONIGHT INTO
TOMORROW. LOCALLY HEAVY RAIN WILL OVERSPREAD THE AREA TONIGHT AND
WILL REDUCE VISIBILITIES AT TIMES AS SOME PATCHY FOG WILL FORM AT
TIMES. WHILE CIGS WILL LIKELY HOLD AT MVFR FOR THE FIRST HALF OF
TONIGHT...AS THE COLD PUSHES ON THROUGH...WE SHOULD SEE CIGS DROP TO
BORDERLINE MVFR/IFR BY TOMORROW MORNING. CIGS WILL LIFT TO MVFR
THROUGH THE DAY TOMORROW...BUT SKIES SHOULD REMAIN OVERCAST. RAIN
WILL END AROUND DAYBREAK...BUT ANOTHER DISTURBANCE COULD BRING A FEW
RAIN SHOWERS BY THE AFTERNOON OR EVENING HOURS. WITH 900MB WINDS
AROUND 50 KNOTS...LLWS WILL REMAIN A CONCERN INTO TOMORROW MORNING.
AS THE FRONT EXITS TOMORROW...WINDY CONDITIONS WILL LIKELY DEVELOP BY
LATE MORNING THROUGH THE AFTERNOON HOURS AS WINDS GUST UP TO 25
KNOTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...JMW
LONG TERM...SHALLENBERGER
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
307 PM EST FRI JAN 2 2015
.UPDATE...
ISSUED AT 1248 PM EST FRI JAN 2 2015
OVER THE LAST FEW HOURS...WHAT REPORTS OF PRECIP WE HAVE HAD IN OR
NEAR THE AREA HAS BEEN IN THE FORM OF RAIN...EVEN FOR LOCATIONS
SEVERAL COUNTIES TO OUR NORTH. WITH SURFACE TEMPS 35 DEGREES OR ABOVE
IN OUR NORTHERN COUNTIES...WENT AHEAD AND TOOK OUT MENTION OF ANY
FREEZING PRECIP FOR THE REMAINDER OF THE AFTERNOON. IT SEEMS AS
THOUGH MOST OF THE NEIGHBORING OFFICES ARE LETTING THEIR FROZEN
PRECIP FALL OUT OF THE FORECAST AS WELL. WAS A BIT CONCERNED ABOUT
THE ONGOING RADAR RETURNS THAT ARE MOVING EASTWARD AND INTO OUR CWA.
EVEN THOUGH MOST OF THESE APPEAR LIGHT...AND MAY NOT MAKE IT TO THE
SURFACE...THOUGHT IT BEST TO BE COVERED AND WENT AHEAD AND
INTRODUCED SLIGHT CHANCES FOR RAIN FOR MUCH OF THE CWA OVER THE NEXT
COUPLE OF HOURS. THIS IS STILL A PRECURSOR TO THE HEAVIER RAIN WHICH
SITS TO OUR WEST AND OUR SOUTH...AND IS STILL SET TO MOVE INTO THE
REGION LATER THIS EVENING/OVERNIGHT.
UPDATE ISSUED AT 1011 AM EST FRI JAN 2 2015
WENT AHEAD AND KEPT THE MENTION OF SLEET AND SNOW MIXING IN WITH RAIN
ACROSS THE NORTHERN PORTION OF THE CWA FOR THE NEXT COUPLE OF HOURS.
TEMPERATURES ARE STILL HOVERING IN THE 33 TO 35 DEGREE RANGE
HERE...BUT MOST OF THE AIR/MOISTURE ALOFT SHOULD STILL BE BELOW FREEZING.
ALSO BUMPED UP POPS IN THIS LOCATION FOR THE NEXT SEVERAL HOURS AS
WELL...AS ISOLATED TO SCATTERED LIGHT SHOWERS CONTINUE TO MOVE FROM
WEST TO EAST ACROSS NORTHERN KY. OTHER REFLECTIVITIES ARE CONTINUING
TO SHOW UP ACROSS THE WESTERN PORTION OF THE CWA MOVING EASTWARD AS
WELL. SO FAR...THE LATEST OBS ARE NOT SHOWING ANY OF THIS MOISTURE
ACTUALLY HITTING THE GROWN...BUT THOUGHT IT BEST TO GO AHEAD AND
INCLUDE THE MENTION OF SLIGHT CHANCES FOR PRECIP OVER THE NEXT FEW
HOURS ACROSS THE WESTERN CWA IN CASE SOMETHING IS ABLE TO WET BULB TO
THE SURFACE. ANY ICE POTENTIAL SHOULD BE OUT OF THE NORTHERN CWA BY
18Z THIS AFTERNOON AS TEMPERATURES CONTINUE TO SLOWLY RISE. THE NEXT
WAVE OF RAIN IS STILL EXPECTED TO ENTER INTO THE SOUTHERN CWA BY THIS
AFTERNOON.
UPDATE ISSUED AT 750 AM EST FRI JAN 2 2015
THE MORNING IS UNFOLDING MOSTLY AS EXPECTED...BUT THE LIGHT PCPN
NORTH OF THE MOUNTAIN PARKWAY IS MAKING ITS WAY TO THE SFC MORE
EFFECTIVELY THAN INITIALLY EXPECTED WHILE TO THE SOUTH THE INBOUND
PCPN HAS BEEN SLOWER TO ARRIVE. HAVE UPDATED THE NEXT SEVERAL HOURS
FOR THESE ADJUSTMENTS TAKING INTO ACCOUNT THE LATEST HRRR SCENARIO.
ALSO FINE TUNED THE T AND TD GRIDS PER THE LATEST OBS AND TRENDS.
THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 340 AM EST FRI JAN 2 2015
08Z SFC ANALYSIS SHOWS HIGH PRESSURE FADING OVER EASTERN KENTUCKY IN
ADVANCE OF A DEVELOPING WX SYSTEM TO THE SOUTHWEST AND AN AREA OF LOW
PRESSURE OFF TO THE NORTHEAST. THE CLOUDS ASSOCIATED WITH THE
SOUTHWEST SYSTEM HAVE OVERSPREAD THE AREA WITH POCKETS OF LIGHT PCPN
SHOWING UP ON THE REGIONAL RADAR...MAINLY SOUTH OF THE STATE
BORDER...THOUGH SOME RETURNS HAVE DEVELOPED ALONG INTERSTATE 64 IN
CENTRAL KENTUCKY...IN LINE WITH THE LATEST HRRR. THROUGH EAST
KENTUCKY TEMPERATURES ARE FAIRLY UNIFORM IN THE MID 30S WHILE
DEWPOINTS ARE GENERALLY IN THE MID 20S. DEW POINT DEPRESSIONS ON THE
ORDER OF 10 DEGREES WILL LEAD TO A CONCERN FOR WETBULBING WITH ANY
EARLY PCPN THIS MORNING THAT SHOULD RESULT IN PATCHES OF SLEET ALONG
WITH THE LIGHT RAIN. WILL CONTINUE TO DEPICT THIS IN THE GRIDS AND
MENTION IT IN THE HWO AND ZONES...THOUGH ANY IMPACTS ARE EXPECTED TO
BE MINIMAL GIVEN PAVEMENT TEMPERATURES ABOVE FREEZING THROUGH THE
EASTERN PARTS OF THE STATE. WINDS REMAIN LIGHT FROM THE SOUTHWEST
THROUGH THE AREA EARLY THIS MORNING.
THE MODELS ARE IN GOOD AGREEMENT ALOFT FOR THE SHORT TERM PORTION OF
THE FORECAST AS THEY ALL SHOW THE SOUTHWESTERN CLOSED LOW GETTING
PARTIALLY PICKED UP BY THE NORTHERN STREAM LATER TODAY. THIS PROCESS
RELEASES A BATCH OF ENERGY AND LOWER HEIGHTS INTO THE CENTRAL PLAINS
BY EVENING WHILE A LARGER PORTION STAYS SEPARATE OVER SOUTHERN NEW
MEXICO. THE EXPELLED NORTHERN WAVE IS QUICKLY ABSORBED INTO THE
LARGER FLOW AND SPREAD OVER THE CENTRAL GREAT LAKES BY MIDDAY
SATURDAY WHILE THE MAIN LOW IS KICKED EAST BY SOME ENERGY RIDING INTO
ITS BACKSIDE LATER SATURDAY. AHEAD OF THESE WAVES...BROAD SOUTHWEST
FLOW WILL SEND WARMER AND MORE MOIST AIR INTO THE TENNESSEE AND OHIO
VALLEYS TODAY THROUGH SATURDAY. GIVEN THE MODEL AGREEMENT HAVE
FOLLOWED THE HIGHER RESOLUTION NAM12 AND HRRR MOST CLOSELY.
SENSIBLE WEATHER WILL FEATURE THE NET RESULT OF A MOISTENING
ENVIRONMENT AND A DEVELOPING SFC LOW TO THE SOUTHWEST...RAIN CHANCES
MOVING IN FROM SOUTHWEST TO NORTHEAST TODAY. THE BETTER CHANCES
ARRIVE AFTER 18Z FOR THE BULK OF THE JKL CWA ALLOWING THE WARMER AIR
TO BRING UP TEMPERATURES WHILE DEWPOINTS CLIMB ABOVE FREEZING MAKING
ALL THE PCPN LIQUID AFTER THE EARLY MORNING POCKETS OF LIGHT MIXED
PCPN. THE REAL SURGE OF SHOWERS WILL ARRIVE LATER TONIGHT AS A
DEVELOPING WARM FRONT LIFTS INTO THE AREA AND PROVIDES A GOOD
FOCUSING MECHANISM FOR THE INCREASINGLY MOIST AIR. BY DAWN SATURDAY
THE DEEPENING SFC LOW OVER THE LOWER MISSISSIPPI VALLEY WILL LIFT ITS
WARM FRONT NORTH OF THE AREA PLACING OUR AREA IN THE WARM SECTOR OF A
RAPIDLY DEVELOPING SYSTEM TO THE WEST. AS A RESULT...WINDS WILL
INCREASE STEADILY DURING THE DAY SATURDAY WITH ENOUGH INSTABILITY
AVAILABLE FOR A RISK OF THUNDER ACROSS THE ENTIRE AREA...POSSIBLY
ARRIVING BEFORE DAWN SATURDAY PER THE LATEST SWODY1. A BREEZY AND
MILD DAY ENSUES AHEAD OF THE SYSTEM/S COLD FRONT LATER SATURDAY WITH
DRY WEATHER EXPECTED FOR A GOOD PORTION OF THE TIME...THOUGH SOME
SCATTERED SHOWERS AND POSSIBLE THUNDERSTORMS WILL BE AROUND EASTERN
KENTUCKY INTO SATURDAY EVENING. WILL HIT THE THUNDER CHANCES AND THE
BREEZY CONDITIONS HARDER IN THE HWO TO BE ISSUED LATER THIS MORNING.
USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPS...TD...AND WINDS
THROUGH 21Z FRIDAY AND THEN THE SUPERBLEND THROUGH 00Z SUNDAY. ONLY
SLIGHTLY TWEAKED POINT TEMPERATURE DATA FOR MAXES AND MINS. AS FOR
POPS...FAVORED A BLEND OF THE HRRR AND NAM12 EARLY THEN MAINLY THE
NAM12 THROUGH TONIGHT AND SATURDAY. ON THE WHOLE...ENDED UP SIMILAR
TO THE MOS BLEND WITH POPS THROUGH THE SHORT TERM...BUT DETAILS WHERE
ADDED TO SHOW SOME BREAKS WITHIN THE WARM SECTOR DRY SLOTTING
EXPECTED ON SATURDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 306 PM EST FRI JAN 2 2015
THE EXTENDED PERIOD BEGINS WARM AND WET ON SUNDAY MORNING JANUARY
THE FOURTH. A LARGE SWATH OF LIGHT TO MODERATE RAIN IS PROGGED TO
MOVE ACROSS THE OHIO AND TENNESSEE VALLEY REGIONS ALONG AND JUST
AHEAD OF A VERY POTENT COLD FRONT. THE RAIN IS EXPECTED TO GRADUALLY
TAPER OFF FROM WEST TO EASTERN SUNDAY AND SUNDAY NIGHT AS THE FRONT
MOVES THROUGH. THE PRECIPITATION SHOULD BE OUT OF THE AREA BY LATE
SUNDAY NIGHT. AFTER THAT...A FRIGID ARCTIC AIR MASS IS EXPECTED TO
SETTLE OVER THE REGION FOR A FEW DAYS. AFTER A MODEST COOL DOWN
SUNDAY NIGHT...DURING WHICH TIME TEMPERATURES ARE EXPECTED TO DROP
INTO THE 20S ACROSS THE AREA...A SECOND REINFORCING SHOT OF COLD AIR
IS EXPECTED TO INVADE THE AREA TUESDAY NIGHT...AS A FAST MOVING
CLIPPER SYSTEM PASSES BY JUST TO OUR NORTH. BASED ON THE LATEST MOS
GUIDANCE AND MODEL SOUNDINGS...THE MERCURY COULD DROP INTO THE TEENS
AND LOW 20S TUESDAY NIGHT...AND PERHAPS EVEN INTO THE SINGLE DIGITS
WEDNESDAY NIGHT. THE CULPRIT OF THESE FRIGID TEMPERATURES WOULD COME
IN THE FORM OF A LARGE RIDGE OF ARCTIC HIGH PRESSURE THAT IS
EXPECTED TO SETTLE OVER THE EASTERN CONUS MID WEEK. AFTER SUNDAY AND
SUNDAY NIGHT...THE ONLY PRECIPITATION THAT MAY AFFECT THE AREA WOULD
COME TUESDAY AFTERNOON AND EVENING AS THE CLIPPER SYSTEM MOVES PAST.
ANY RAIN OR SNOW THAT FALLS THAT DAY WOULD LIKELY OCCUR NORTH OF THE
MOUNTAIN PARKWAY WITH LITTLE ACCUMULATION EXPECTED. THE REST OF THE
WEEK IS FORECAST TO BE DRY AND QUITE COLD. HIGHS ON WEDNESDAY AND
THURSDAY MAY NOT CLIMB OUT OF THE 20S. MONDAY LOOKS TO BE PRETTY
COLD AS WELL...WITH HIGHS IN THE 30S ANTICIPATED ON THAT DAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 140 PM EST FRI JAN 2 2015
SOME LIGHT RAIN SHOWERS ARE CURRENTLY MAKING THEIR WAY ACROSS THE
WESTERN AND NORTHERN PART OF THE FORECAST AREA. CIGS ARE STILL
HOLDING STEADY AT MVFR ACROSS MUCH OF THE REGION. LOWER CIGS IN THE
IFR OR LIFR RANGE ARE EXPECTED TONIGHT ALONG WITH RAIN AND BR LEADING
TO VIS RESTRICTIONS. LIGHT SOUTHWEST WINDS CAN BE EXPECTED THROUGH
THE DAY WITH AN INCREASE IN SPEEDS JUST OFF THE SFC TONIGHT FROM THE
SOUTHWEST. HAVE ADDED LLWS FOR THIS AT UP TO 35 KTS AT 1500 FEET TO
ALL THE TAFS STARTING AT EARLY AS 6Z. WENT AHEAD AND ADDED IN VCTS
FROM 6Z AND THROUGH TOMORROW AS THUNDERSTORMS ARE LIKELY TO MOVE INTO
THE AREA AT SOME POINT TONIGHT/TOMORROW...THOUGH EXACT TIMING AND
LOCATION OF WHERE THEY WILL SET UP IS STILL UNKNOWN.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...GREIF
LONG TERM...AR
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
148 PM EST FRI JAN 2 2015
.UPDATE...
ISSUED AT 1248 PM EST FRI JAN 2 2015
OVER THE LAST FEW HOURS...WHAT REPORTS OF PRECIP WE HAVE HAD IN OR
NEAR THE AREA HAS BEEN IN THE FORM OF RAIN...EVEN FOR LOCATIONS
SEVERAL COUNTIES TO OUR NORTH. WITH SURFACE TEMPS 35 DEGREES OR ABOVE
IN OUR NORTHERN COUNTIES...WENT AHEAD AND TOOK OUT MENTION OF ANY
FREEZING PRECIP FOR THE REMAINDER OF THE AFTERNOON. IT SEEMS AS
THOUGH MOST OF THE NEIGHBORING OFFICES ARE LETTING THEIR FROZEN
PRECIP FALL OUT OF THE FORECAST AS WELL. WAS A BIT CONCERNED ABOUT
THE ONGOING RADAR RETURNS THAT ARE MOVING EASTWARD AND INTO OUR CWA.
EVEN THOUGH MOST OF THESE APPEAR LIGHT...AND MAY NOT MAKE IT TO THE
SURFACE...THOUGHT IT BEST TO BE COVERED AND WENT AHEAD AND
INTRODUCED SLIGHT CHANCES FOR RAIN FOR MUCH OF THE CWA OVER THE NEXT
COUPLE OF HOURS. THIS IS STILL A PRECURSOR TO THE HEAVIER RAIN WHICH
SITS TO OUR WEST AND OUR SOUTH...AND IS STILL SET TO MOVE INTO THE
REGION LATER THIS EVENING/OVERNIGHT.
UPDATE ISSUED AT 1011 AM EST FRI JAN 2 2015
WENT AHEAD AND KEPT THE MENTION OF SLEET AND SNOW MIXING IN WITH RAIN
ACROSS THE NORTHERN PORTION OF THE CWA FOR THE NEXT COUPLE OF HOURS.
TEMPERATURES ARE STILL HOVERING IN THE 33 TO 35 DEGREE RANGE
HERE...BUT MOST OF THE AIR/MOISTURE ALOFT SHOULD STILL BE BELOW FREEZING.
ALSO BUMPED UP POPS IN THIS LOCATION FOR THE NEXT SEVERAL HOURS AS
WELL...AS ISOLATED TO SCATTERED LIGHT SHOWERS CONTINUE TO MOVE FROM
WEST TO EAST ACROSS NORTHERN KY. OTHER REFLECTIVITIES ARE CONTINUING
TO SHOW UP ACROSS THE WESTERN PORTION OF THE CWA MOVING EASTWARD AS
WELL. SO FAR...THE LATEST OBS ARE NOT SHOWING ANY OF THIS MOISTURE
ACTUALLY HITTING THE GROWN...BUT THOUGHT IT BEST TO GO AHEAD AND
INCLUDE THE MENTION OF SLIGHT CHANCES FOR PRECIP OVER THE NEXT FEW
HOURS ACROSS THE WESTERN CWA IN CASE SOMETHING IS ABLE TO WETBULB TO
THE SURFACE. ANY ICE POTENTIAL SHOULD BE OUT OF THE NORTHERN CWA BY
18Z THIS AFTERNOON AS TEMPERATURES CONTINUE TO SLOWLY RISE. THE NEXT
WAVE OF RAIN IS STILL EXPECTED TO ENTER INTO THE SOUTHERN CWA BY THIS
AFTERNOON.
UPDATE ISSUED AT 750 AM EST FRI JAN 2 2015
THE MORNING IS UNFOLDING MOSTLY AS EXPECTED...BUT THE LIGHT PCPN
NORTH OF THE MOUNTAIN PARKWAY IS MAKING ITS WAY TO THE SFC MORE
EFFECTIVELY THAN INITIALLY EXPECTED WHILE TO THE SOUTH THE INBOUND
PCPN HAS BEEN SLOWER TO ARRIVE. HAVE UPDATED THE NEXT SEVERAL HOURS
FOR THESE ADJUSTMENTS TAKING INTO ACCOUNT THE LATEST HRRR SCENARIO.
ALSO FINE TUNED THE T AND TD GRIDS PER THE LATEST OBS AND TRENDS.
THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 340 AM EST FRI JAN 2 2015
08Z SFC ANALYSIS SHOWS HIGH PRESSURE FADING OVER EASTERN KENTUCKY IN
ADVANCE OF A DEVELOPING WX SYSTEM TO THE SOUTHWEST AND AN AREA OF LOW
PRESSURE OFF TO THE NORTHEAST. THE CLOUDS ASSOCIATED WITH THE
SOUTHWEST SYSTEM HAVE OVERSPREAD THE AREA WITH POCKETS OF LIGHT PCPN
SHOWING UP ON THE REGIONAL RADAR...MAINLY SOUTH OF THE STATE
BORDER...THOUGH SOME RETURNS HAVE DEVELOPED ALONG INTERSTATE 64 IN
CENTRAL KENTUCKY...IN LINE WITH THE LATEST HRRR. THROUGH EAST
KENTUCKY TEMPERATURES ARE FAIRLY UNIFORM IN THE MID 30S WHILE
DEWPOINTS ARE GENERALLY IN THE MID 20S. DEW POINT DEPRESSIONS ON THE
ORDER OF 10 DEGREES WILL LEAD TO A CONCERN FOR WETBULBING WITH ANY
EARLY PCPN THIS MORNING THAT SHOULD RESULT IN PATCHES OF SLEET ALONG
WITH THE LIGHT RAIN. WILL CONTINUE TO DEPICT THIS IN THE GRIDS AND
MENTION IT IN THE HWO AND ZONES...THOUGH ANY IMPACTS ARE EXPECTED TO
BE MINIMAL GIVEN PAVEMENT TEMPERATURES ABOVE FREEZING THROUGH THE
EASTERN PARTS OF THE STATE. WINDS REMAIN LIGHT FROM THE SOUTHWEST
THROUGH THE AREA EARLY THIS MORNING.
THE MODELS ARE IN GOOD AGREEMENT ALOFT FOR THE SHORT TERM PORTION OF
THE FORECAST AS THEY ALL SHOW THE SOUTHWESTERN CLOSED LOW GETTING
PARTIALLY PICKED UP BY THE NORTHERN STREAM LATER TODAY. THIS PROCESS
RELEASES A BATCH OF ENERGY AND LOWER HEIGHTS INTO THE CENTRAL PLAINS
BY EVENING WHILE A LARGER PORTION STAYS SEPARATE OVER SOUTHERN NEW
MEXICO. THE EXPELLED NORTHERN WAVE IS QUICKLY ABSORBED INTO THE
LARGER FLOW AND SPREAD OVER THE CENTRAL GREAT LAKES BY MIDDAY
SATURDAY WHILE THE MAIN LOW IS KICKED EAST BY SOME ENERGY RIDING INTO
ITS BACKSIDE LATER SATURDAY. AHEAD OF THESE WAVES...BROAD SOUTHWEST
FLOW WILL SEND WARMER AND MORE MOIST AIR INTO THE TENNESSEE AND OHIO
VALLEYS TODAY THROUGH SATURDAY. GIVEN THE MODEL AGREEMENT HAVE
FOLLOWED THE HIGHER RESOLUTION NAM12 AND HRRR MOST CLOSELY.
SENSIBLE WEATHER WILL FEATURE THE NET RESULT OF A MOISTENING
ENVIRONMENT AND A DEVELOPING SFC LOW TO THE SOUTHWEST...RAIN CHANCES
MOVING IN FROM SOUTHWEST TO NORTHEAST TODAY. THE BETTER CHANCES
ARRIVE AFTER 18Z FOR THE BULK OF THE JKL CWA ALLOWING THE WARMER AIR
TO BRING UP TEMPERATURES WHILE DEWPOINTS CLIMB ABOVE FREEZING MAKING
ALL THE PCPN LIQUID AFTER THE EARLY MORNING POCKETS OF LIGHT MIXED
PCPN. THE REAL SURGE OF SHOWERS WILL ARRIVE LATER TONIGHT AS A
DEVELOPING WARM FRONT LIFTS INTO THE AREA AND PROVIDES A GOOD
FOCUSING MECHANISM FOR THE INCREASINGLY MOIST AIR. BY DAWN SATURDAY
THE DEEPENING SFC LOW OVER THE LOWER MISSISSIPPI VALLEY WILL LIFT ITS
WARM FRONT NORTH OF THE AREA PLACING OUR AREA IN THE WARM SECTOR OF A
RAPIDLY DEVELOPING SYSTEM TO THE WEST. AS A RESULT...WINDS WILL
INCREASE STEADILY DURING THE DAY SATURDAY WITH ENOUGH INSTABILITY
AVAILABLE FOR A RISK OF THUNDER ACROSS THE ENTIRE AREA...POSSIBLY
ARRIVING BEFORE DAWN SATURDAY PER THE LATEST SWODY1. A BREEZY AND
MILD DAY ENSUES AHEAD OF THE SYSTEM/S COLD FRONT LATER SATURDAY WITH
DRY WEATHER EXPECTED FOR A GOOD PORTION OF THE TIME...THOUGH SOME
SCATTERED SHOWERS AND POSSIBLE THUNDERSTORMS WILL BE AROUND EASTERN
KENTUCKY INTO SATURDAY EVENING. WILL HIT THE THUNDER CHANCES AND THE
BREEZY CONDITIONS HARDER IN THE HWO TO BE ISSUED LATER THIS MORNING.
USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPS...TD...AND WINDS
THROUGH 21Z FRIDAY AND THEN THE SUPERBLEND THROUGH 00Z SUNDAY. ONLY
SLIGHTLY TWEAKED POINT TEMPERATURE DATA FOR MAXES AND MINS. AS FOR
POPS...FAVORED A BLEND OF THE HRRR AND NAM12 EARLY THEN MAINLY THE
NAM12 THROUGH TONIGHT AND SATURDAY. ON THE WHOLE...ENDED UP SIMILAR
TO THE MOS BLEND WITH POPS THROUGH THE SHORT TERM...BUT DETAILS WHERE
ADDED TO SHOW SOME BREAKS WITHIN THE WARM SECTOR DRY SLOTTING
EXPECTED ON SATURDAY.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 357 AM EST FRI JAN 2 2015
THE EXTENDED FORECAST PERIOD BEGINS ON SATURDAY NIGHT WITH AN
AMPLIFIED UPPER LEVEL PATTERN OVER THE CONUS. A LARGE LONGWAVE
TROUGH MOVES THROUGH THE CENTRAL PAINS AND INTO THE MS RIVER VALLEY.
AT THIS TIME A POTENT SHORT WAVE IS LIFTING OUT OF THE MID MS RIVER
VALLEY AND MOVING INTO THE OH VALLEY...WHILE A SECOND STRONG
SHORTWAVE DEVELOPS ALONG THE LOWER PORTION OF THE MS VALLEY AND
QUICK LIFTS NORTHEAST AS WELL INTO THE LOWER APPALACHIAN RANGE. A
STRONG JET DEVELOPING IN THE UPPER LEVELS ON SUNDAY NIGHT OVER THE
MID ATLANTIC WILL LIFT THE UPPER LEVEL TROUGH NORTHEAST INTO THE NEW
ENGLAND AREA. THIS SETS THE PATTERN FROM MONDAY THROUGH THURSDAY OF
A SEMI PERMANENT UPPER LEVEL LONGWAVE TROUGH OVER THE GREAT LAKES
AND NEW ENGLAND AREA. THIS CYCLONIC FLOW OVER THE NORTHEASTERN CONUS
WILL LEAD TO NORTHWEST FLOW FOR EASTERN KENTUCKY THROUGH THE REST OF
THE EXTENDED.
CLOSER TO THE SURFACE FOR THE FRONT MOVING THROUGH SAT NIGHT THROUGH
SUNDAY NIGHT...THE INHERITED FORECAST AND RESULT OF THE BLEND OF
MODELS LEAVES QUITE A BIT OF PRECIP MOVING THROUGH SAT NIGHT THROUGH
SUNDAY. PWATS DURING THIS TIME WITH MODEL SOUNDINGS SHOW 1.34 INCHES
WHICH IS AMPLE THIS TIME OF YEAR. HPC RESULTS ALONG WITH THE MODEL
BLEND PUT AROUND AN INCH IN THE AREA FOR THE STA NIGHT AND SUNDAY
TIME FRAME AND HAVE GONE WITH THESE VALUES AS THOUGH...WEAKENING THE
SHOWERS WITH THE FRONT MOVING THROUGH COULD PRODUCE SOME DECENT
RAINFALL AT TIMES. AS MENTIONED WITH THE LOW SHOWING A WEAKENING
TREND...THERE IS A DECENT AMOUNT OF ISENTROPIC LIFT AHEAD AND WITH
THIS FRONT AND WITH THE INHERITED FORECAST COUPLED WITH A CONSENSUS
OF NEIGHBORING OFFICES...DECIDED TO KEEP A SLIGHT CHANCE OF THUNDER
IN THE SATURDAY NIGHT PORTION. AS MENTIONED WITH THE PROGRESSIVE
FLOW AND QUICK EXIT OF THIS FEATURE...PRECIP HANGING UP ON THE
EASTERN RIDGES SHOULD BE SHORT IN DURATION AND HAVE ALL POPS
EXITING EARLY SUNDAY NIGHT. AS SUCH...THE MOISTURE WILL EXIT THE
AREA BEFORE ANY COLD AIR FILTERS IN. ANY CHANGE OVER TO SNOW ACROSS
THE AREA IS NOT EXPECTED.
THE DRIER NORTHWEST FLOW SETTING UP BY TUESDAY WILL HINDER PRECIP
MAKING IT FAR ENOUGH SOUTH INTO EASTERN KENTUCKY FOR SNOWFALL. BASED
ON INHERITED FORECAST...PATTERN RECOGNITION AND COLLABORATION WITH
THE NEIGHBORING OFFICES...HAVE GONE DRY WITH THE WEAK SHORTWAVE
MOVING THROUGH THE OH VALLEY TUESDAY NIGHT INTO WEDNESDAY. WHILE A
FEW FLURRIES ARE POSSIBLE AS WELL...THE GENERAL TREND WITH THIS IS
THAT AS MOISTURE STARVED AS THESE CLIPPER SYSTEMS ARE...THE BULK OF
THE UPPER LEVEL SUPPORT STAYS TO THE NORTH WITH THIS WAVE. AFTER
SUNDAY NIGHT...HAVE GONE DRY OVER EASTERN KENTUCKY FOR THE REST OF
THE FORECAST. THE DEW POINTS WITH THIS ARCTIC AIR MASS MOVING IN
DURING THE LAST PART OF THE EXTENDED IS QUITE IMPRESSIVE. QUITE A
COLD AND DRY AIR MASS MAKES ITS PRESENCE KNOWN DIVING SOUTH INTO THE
CENTRAL CONUS AND MEANDERING SOUTHEAST BY THE END OF THE EXTENDED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 140 PM EST FRI JAN 2 2015
SOME LIGHT RAIN SHOWERS ARE CURRENTLY MAKING THEIR WAY ACROSS THE
WESTERN AND NORTHERN PART OF THE FORECAST AREA. CIGS ARE STILL
HOLDING STEADY AT MVFR ACROSS MUCH OF THE REGION. LOWER CIGS IN THE
IFR OR LIFR RANGE ARE EXPECTED TONIGHT ALONG WITH RAIN AND BR LEADING
TO VIS RESTRICTIONS. LIGHT SOUTHWEST WINDS CAN BE EXPECTED THROUGH
THE DAY WITH AN INCREASE IN SPEEDS JUST OFF THE SFC TONIGHT FROM THE
SOUTHWEST. HAVE ADDED LLWS FOR THIS AT UP TO 35 KTS AT 1500 FEET TO
ALL THE TAFS STARTING AT EARLY AS 6Z. WENT AHEAD AND ADDED IN VCTS
FROM 6Z AND THROUGH TOMORROW AS THUNDERSTORMS ARE LIKELY TO MOVE INTO
THE AREA AT SOME POINT TONIGHT/TOMORROW...THOUGH EXACT TIMING AND
LOCATION OF WHERE THEY WILL SET UP IS STILL UNKNOWN.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
1012 AM EST FRI JAN 2 2015
.UPDATE...
ISSUED AT 1011 AM EST FRI JAN 2 2015
WENT AHEAD AND KEPT THE MENTION OF SLEET AND SNOW MIXING IN WITH RAIN
ACROSS THE NORTHERN PORTION OF THE CWA FOR THE NEXT COUPLE OF HOURS.
TEMPERATURES ARE STILL HOVERING IN THE 33 TO 35 DEGREE RANGE
HERE...BUT MOST OF THE AIR/MOISTURE ALOFT SHOULD STILL BE BELOW FREEZING.
ALSO BUMPED UP POPS IN THIS LOCATION FOR THE NEXT SEVERAL HOURS AS
WELL...AS ISOLATED TO SCATTERED LIGHT SHOWERS CONTINUE TO MOVE FROM
WEST TO EAST ACROSS NORTHERN KY. OTHER REFLECTIVITIES ARE CONTINUING
TO SHOW UP ACROSS THE WESTERN PORTION OF THE CWA MOVING EASTWARD AS
WELL. SO FAR...THE LATEST OBS ARE NOT SHOWING ANY OF THIS MOISTURE
ACTUALLY HITTING THE GROWN...BUT THOUGHT IT BEST TO GO AHEAD AND
INCLUDE THE MENTION OF SLIGHT CHANCES FOR PRECIP OVER THE NEXT FEW
HOURS ACROSS THE WESTERN CWA IN CASE SOMETHING IS ABLE TO WETBULB TO
THE SURFACE. ANY ICE POTENTIAL SHOULD BE OUT OF THE NORTHERN CWA BY
18Z THIS AFTERNOON AS TEMPERATURES CONTINUE TO SLOWLY RISE. THE NEXT
WAVE OF RAIN IS STILL EXPECTED TO ENTER INTO THE SOUTHERN CWA BY THIS
AFTERNOON.
UPDATE ISSUED AT 750 AM EST FRI JAN 2 2015
THE MORNING IS UNFOLDING MOSTLY AS EXPECTED...BUT THE LIGHT PCPN
NORTH OF THE MOUNTAIN PARKWAY IS MAKING ITS WAY TO THE SFC MORE
EFFECTIVELY THAN INITIALLY EXPECTED WHILE TO THE SOUTH THE INBOUND
PCPN HAS BEEN SLOWER TO ARRIVE. HAVE UPDATED THE NEXT SEVERAL HOURS
FOR THESE ADJUSTMENTS TAKING INTO ACCOUNT THE LATEST HRRR SCENARIO.
ALSO FINE TUNED THE T AND TD GRIDS PER THE LATEST OBS AND TRENDS.
THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 340 AM EST FRI JAN 2 2015
08Z SFC ANALYSIS SHOWS HIGH PRESSURE FADING OVER EASTERN KENTUCKY IN
ADVANCE OF A DEVELOPING WX SYSTEM TO THE SOUTHWEST AND AN AREA OF LOW
PRESSURE OFF TO THE NORTHEAST. THE CLOUDS ASSOCIATED WITH THE
SOUTHWEST SYSTEM HAVE OVERSPREAD THE AREA WITH POCKETS OF LIGHT PCPN
SHOWING UP ON THE REGIONAL RADAR...MAINLY SOUTH OF THE STATE
BORDER...THOUGH SOME RETURNS HAVE DEVELOPED ALONG INTERSTATE 64 IN
CENTRAL KENTUCKY...IN LINE WITH THE LATEST HRRR. THROUGH EAST
KENTUCKY TEMPERATURES ARE FAIRLY UNIFORM IN THE MID 30S WHILE
DEWPOINTS ARE GENERALLY IN THE MID 20S. DEW POINT DEPRESSIONS ON THE
ORDER OF 10 DEGREES WILL LEAD TO A CONCERN FOR WETBULBING WITH ANY
EARLY PCPN THIS MORNING THAT SHOULD RESULT IN PATCHES OF SLEET ALONG
WITH THE LIGHT RAIN. WILL CONTINUE TO DEPICT THIS IN THE GRIDS AND
MENTION IT IN THE HWO AND ZONES...THOUGH ANY IMPACTS ARE EXPECTED TO
BE MINIMAL GIVEN PAVEMENT TEMPERATURES ABOVE FREEZING THROUGH THE
EASTERN PARTS OF THE STATE. WINDS REMAIN LIGHT FROM THE SOUTHWEST
THROUGH THE AREA EARLY THIS MORNING.
THE MODELS ARE IN GOOD AGREEMENT ALOFT FOR THE SHORT TERM PORTION OF
THE FORECAST AS THEY ALL SHOW THE SOUTHWESTERN CLOSED LOW GETTING
PARTIALLY PICKED UP BY THE NORTHERN STREAM LATER TODAY. THIS PROCESS
RELEASES A BATCH OF ENERGY AND LOWER HEIGHTS INTO THE CENTRAL PLAINS
BY EVENING WHILE A LARGER PORTION STAYS SEPARATE OVER SOUTHERN NEW
MEXICO. THE EXPELLED NORTHERN WAVE IS QUICKLY ABSORBED INTO THE
LARGER FLOW AND SPREAD OVER THE CENTRAL GREAT LAKES BY MIDDAY
SATURDAY WHILE THE MAIN LOW IS KICKED EAST BY SOME ENERGY RIDING INTO
ITS BACKSIDE LATER SATURDAY. AHEAD OF THESE WAVES...BROAD SOUTHWEST
FLOW WILL SEND WARMER AND MORE MOIST AIR INTO THE TENNESSEE AND OHIO
VALLEYS TODAY THROUGH SATURDAY. GIVEN THE MODEL AGREEMENT HAVE
FOLLOWED THE HIGHER RESOLUTION NAM12 AND HRRR MOST CLOSELY.
SENSIBLE WEATHER WILL FEATURE THE NET RESULT OF A MOISTENING
ENVIRONMENT AND A DEVELOPING SFC LOW TO THE SOUTHWEST...RAIN CHANCES
MOVING IN FROM SOUTHWEST TO NORTHEAST TODAY. THE BETTER CHANCES
ARRIVE AFTER 18Z FOR THE BULK OF THE JKL CWA ALLOWING THE WARMER AIR
TO BRING UP TEMPERATURES WHILE DEWPOINTS CLIMB ABOVE FREEZING MAKING
ALL THE PCPN LIQUID AFTER THE EARLY MORNING POCKETS OF LIGHT MIXED
PCPN. THE REAL SURGE OF SHOWERS WILL ARRIVE LATER TONIGHT AS A
DEVELOPING WARM FRONT LIFTS INTO THE AREA AND PROVIDES A GOOD
FOCUSING MECHANISM FOR THE INCREASINGLY MOIST AIR. BY DAWN SATURDAY
THE DEEPENING SFC LOW OVER THE LOWER MISSISSIPPI VALLEY WILL LIFT ITS
WARM FRONT NORTH OF THE AREA PLACING OUR AREA IN THE WARM SECTOR OF A
RAPIDLY DEVELOPING SYSTEM TO THE WEST. AS A RESULT...WINDS WILL
INCREASE STEADILY DURING THE DAY SATURDAY WITH ENOUGH INSTABILITY
AVAILABLE FOR A RISK OF THUNDER ACROSS THE ENTIRE AREA...POSSIBLY
ARRIVING BEFORE DAWN SATURDAY PER THE LATEST SWODY1. A BREEZY AND
MILD DAY ENSUES AHEAD OF THE SYSTEM/S COLD FRONT LATER SATURDAY WITH
DRY WEATHER EXPECTED FOR A GOOD PORTION OF THE TIME...THOUGH SOME
SCATTERED SHOWERS AND POSSIBLE THUNDERSTORMS WILL BE AROUND EASTERN
KENTUCKY INTO SATURDAY EVENING. WILL HIT THE THUNDER CHANCES AND THE
BREEZY CONDITIONS HARDER IN THE HWO TO BE ISSUED LATER THIS MORNING.
USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPS...TD...AND WINDS
THROUGH 21Z FRIDAY AND THEN THE SUPERBLEND THROUGH 00Z SUNDAY. ONLY
SLIGHTLY TWEAKED POINT TEMPERATURE DATA FOR MAXES AND MINS. AS FOR
POPS...FAVORED A BLEND OF THE HRRR AND NAM12 EARLY THEN MAINLY THE
NAM12 THROUGH TONIGHT AND SATURDAY. ON THE WHOLE...ENDED UP SIMILAR
TO THE MOS BLEND WITH POPS THROUGH THE SHORT TERM...BUT DETAILS WHERE
ADDED TO SHOW SOME BREAKS WITHIN THE WARM SECTOR DRY SLOTTING
EXPECTED ON SATURDAY.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 357 AM EST FRI JAN 2 2015
THE EXTENDED FORECAST PERIOD BEGINS ON SATURDAY NIGHT WITH AN
AMPLIFIED UPPER LEVEL PATTERN OVER THE CONUS. A LARGE LONGWAVE
TROUGH MOVES THROUGH THE CENTRAL PAINS AND INTO THE MS RIVER VALLEY.
AT THIS TIME A POTENT SHORT WAVE IS LIFTING OUT OF THE MID MS RIVER
VALLEY AND MOVING INTO THE OH VALLEY...WHILE A SECOND STRONG
SHORTWAVE DEVELOPS ALONG THE LOWER PORTION OF THE MS VALLEY AND
QUICK LIFTS NORTHEAST AS WELL INTO THE LOWER APPALACHIAN RANGE. A
STRONG JET DEVELOPING IN THE UPPER LEVELS ON SUNDAY NIGHT OVER THE
MID ATLANTIC WILL LIFT THE UPPER LEVEL TROUGH NORTHEAST INTO THE NEW
ENGLAND AREA. THIS SETS THE PATTERN FROM MONDAY THROUGH THURSDAY OF
A SEMI PERMANENT UPPER LEVEL LONGWAVE TROUGH OVER THE GREAT LAKES
AND NEW ENGLAND AREA. THIS CYCLONIC FLOW OVER THE NORTHEASTERN CONUS
WILL LEAD TO NORTHWEST FLOW FOR EASTERN KENTUCKY THROUGH THE REST OF
THE EXTENDED.
CLOSER TO THE SURFACE FOR THE FRONT MOVING THROUGH SAT NIGHT THROUGH
SUNDAY NIGHT...THE INHERITED FORECAST AND RESULT OF THE BLEND OF
MODELS LEAVES QUITE A BIT OF PRECIP MOVING THROUGH SAT NIGHT THROUGH
SUNDAY. PWATS DURING THIS TIME WITH MODEL SOUNDINGS SHOW 1.34 INCHES
WHICH IS AMPLE THIS TIME OF YEAR. HPC RESULTS ALONG WITH THE MODEL
BLEND PUT AROUND AN INCH IN THE AREA FOR THE STA NIGHT AND SUNDAY
TIME FRAME AND HAVE GONE WITH THESE VALUES AS THOUGH...WEAKENING THE
SHOWERS WITH THE FRONT MOVING THROUGH COULD PRODUCE SOME DECENT
RAINFALL AT TIMES. AS MENTIONED WITH THE LOW SHOWING A WEAKENING
TREND...THERE IS A DECENT AMOUNT OF ISENTROPIC LIFT AHEAD AND WITH
THIS FRONT AND WITH THE INHERITED FORECAST COUPLED WITH A CONSENSUS
OF NEIGHBORING OFFICES...DECIDED TO KEEP A SLIGHT CHANCE OF THUNDER
IN THE SATURDAY NIGHT PORTION. AS MENTIONED WITH THE PROGRESSIVE
FLOW AND QUICK EXIT OF THIS FEATURE...PRECIP HANGING UP ON THE
EASTERN RIDGES SHOULD BE SHORT IN DURATION AND HAVE ALL POPS
EXITING EARLY SUNDAY NIGHT. AS SUCH...THE MOISTURE WILL EXIT THE
AREA BEFORE ANY COLD AIR FILTERS IN. ANY CHANGE OVER TO SNOW ACROSS
THE AREA IS NOT EXPECTED.
THE DRIER NORTHWEST FLOW SETTING UP BY TUESDAY WILL HINDER PRECIP
MAKING IT FAR ENOUGH SOUTH INTO EASTERN KENTUCKY FOR SNOWFALL. BASED
ON INHERITED FORECAST...PATTERN RECOGNITION AND COLLABORATION WITH
THE NEIGHBORING OFFICES...HAVE GONE DRY WITH THE WEAK SHORTWAVE
MOVING THROUGH THE OH VALLEY TUESDAY NIGHT INTO WEDNESDAY. WHILE A
FEW FLURRIES ARE POSSIBLE AS WELL...THE GENERAL TREND WITH THIS IS
THAT AS MOISTURE STARVED AS THESE CLIPPER SYSTEMS ARE...THE BULK OF
THE UPPER LEVEL SUPPORT STAYS TO THE NORTH WITH THIS WAVE. AFTER
SUNDAY NIGHT...HAVE GONE DRY OVER EASTERN KENTUCKY FOR THE REST OF
THE FORECAST. THE DEW POINTS WITH THIS ARCTIC AIR MASS MOVING IN
DURING THE LAST PART OF THE EXTENDED IS QUITE IMPRESSIVE. QUITE A
COLD AND DRY AIR MASS MAKES ITS PRESENCE KNOWN DIVING SOUTH INTO THE
CENTRAL CONUS AND MEANDERING SOUTHEAST BY THE END OF THE EXTENDED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 715 AM EST FRI JAN 2 2015
CIGS HAVE FALLEN TO MVFR IN THE SOUTHERN PARTS OF THE AREA UP TO JKL
AND NOW SJS. THESE WILL STAY LOW THROUGH THE REMAINDER OF THE TAF
PERIOD AS THE LOW LEVELS OF THE ATMOSPHERE FURTHER SATURATE. LIGHT
PCPN WILL AFFECT THE AREA THIS MORNING...FALLING MOSTLY AS RAIN...
HOWEVER SOME SLEET WILL BE POSSIBLE AT THE ONSET. EXPECT MVFR CLOUDS
TO OVERTAKE THE REST OF THE AREA FROM SOUTH TO NORTH THROUGH THE
MORNING...WITH LOCATIONS NORTH OF THE I-64 CORRIDOR LIKELY STAYING
LOW VFR UNTIL THIS AFTERNOON WHEN A DEVELOPING WARM FRONT LIFTS INTO
THIS PART OF KENTUCKY FROM THE SOUTH. LOWER CIGS IN THE IFR OR LIFR
RANGE ARE EXPECTED TONIGHT ALONG WITH RAIN AND BR LEADING TO VIS
RESTRICTIONS. SOUTHWEST WINDS OF 5 TO 10 KTS CAN BE EXPECTED THROUGH
THE DAY WITH AN INCREASE IN SPEEDS JUST OFF THE SFC TONIGHT FROM THE
SOUTHWEST. HAVE ADDED LLWS FOR THIS AT UP TO 35 KTS AT 1500 FEET TO
ALL THE TAFS STARTING AT EARLY AS 6Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
750 AM EST FRI JAN 2 2015
.UPDATE...
ISSUED AT 750 AM EST FRI JAN 2 2015
THE MORNING IS UNFOLDING MOSTLY AS EXPECTED...BUT THE LIGHT PCPN
NORTH OF THE MOUNTAIN PARKWAY IS MAKING ITS WAY TO THE SFC MORE
EFFECTIVELY THAN INITIALLY EXPECTED WHILE TO THE SOUTH THE INBOUND
PCPN HAS BEEN SLOWER TO ARRIVE. HAVE UPDATED THE NEXT SEVERAL HOURS
FOR THESE ADJUSTMENTS TAKING INTO ACCOUNT THE LATEST HRRR SCENARIO.
ALSO FINE TUNED THE T AND TD GRIDS PER THE LATEST OBS AND TRENDS.
THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 340 AM EST FRI JAN 2 2015
08Z SFC ANALYSIS SHOWS HIGH PRESSURE FADING OVER EASTERN KENTUCKY IN
ADVANCE OF A DEVELOPING WX SYSTEM TO THE SOUTHWEST AND AN AREA OF LOW
PRESSURE OFF TO THE NORTHEAST. THE CLOUDS ASSOCIATED WITH THE
SOUTHWEST SYSTEM HAVE OVERSPREAD THE AREA WITH POCKETS OF LIGHT PCPN
SHOWING UP ON THE REGIONAL RADAR...MAINLY SOUTH OF THE STATE
BORDER...THOUGH SOME RETURNS HAVE DEVELOPED ALONG INTERSTATE 64 IN
CENTRAL KENTUCKY...IN LINE WITH THE LATEST HRRR. THROUGH EAST
KENTUCKY TEMPERATURES ARE FAIRLY UNIFORM IN THE MID 30S WHILE
DEWPOINTS ARE GENERALLY IN THE MID 20S. DEW POINT DEPRESSIONS ON THE
ORDER OF 10 DEGREES WILL LEAD TO A CONCERN FOR WETBULBING WITH ANY
EARLY PCPN THIS MORNING THAT SHOULD RESULT IN PATCHES OF SLEET ALONG
WITH THE LIGHT RAIN. WILL CONTINUE TO DEPICT THIS IN THE GRIDS AND
MENTION IT IN THE HWO AND ZONES...THOUGH ANY IMPACTS ARE EXPECTED TO
BE MINIMAL GIVEN PAVEMENT TEMPERATURES ABOVE FREEZING THROUGH THE
EASTERN PARTS OF THE STATE. WINDS REMAIN LIGHT FROM THE SOUTHWEST
THROUGH THE AREA EARLY THIS MORNING.
THE MODELS ARE IN GOOD AGREEMENT ALOFT FOR THE SHORT TERM PORTION OF
THE FORECAST AS THEY ALL SHOW THE SOUTHWESTERN CLOSED LOW GETTING
PARTIALLY PICKED UP BY THE NORTHERN STREAM LATER TODAY. THIS PROCESS
RELEASES A BATCH OF ENERGY AND LOWER HEIGHTS INTO THE CENTRAL PLAINS
BY EVENING WHILE A LARGER PORTION STAYS SEPARATE OVER SOUTHERN NEW
MEXICO. THE EXPELLED NORTHERN WAVE IS QUICKLY ABSORBED INTO THE
LARGER FLOW AND SPREAD OVER THE CENTRAL GREAT LAKES BY MIDDAY
SATURDAY WHILE THE MAIN LOW IS KICKED EAST BY SOME ENERGY RIDING INTO
ITS BACKSIDE LATER SATURDAY. AHEAD OF THESE WAVES...BROAD SOUTHWEST
FLOW WILL SEND WARMER AND MORE MOIST AIR INTO THE TENNESSEE AND OHIO
VALLEYS TODAY THROUGH SATURDAY. GIVEN THE MODEL AGREEMENT HAVE
FOLLOWED THE HIGHER RESOLUTION NAM12 AND HRRR MOST CLOSELY.
SENSIBLE WEATHER WILL FEATURE THE NET RESULT OF A MOISTENING
ENVIRONMENT AND A DEVELOPING SFC LOW TO THE SOUTHWEST...RAIN CHANCES
MOVING IN FROM SOUTHWEST TO NORTHEAST TODAY. THE BETTER CHANCES
ARRIVE AFTER 18Z FOR THE BULK OF THE JKL CWA ALLOWING THE WARMER AIR
TO BRING UP TEMPERATURES WHILE DEWPOINTS CLIMB ABOVE FREEZING MAKING
ALL THE PCPN LIQUID AFTER THE EARLY MORNING POCKETS OF LIGHT MIXED
PCPN. THE REAL SURGE OF SHOWERS WILL ARRIVE LATER TONIGHT AS A
DEVELOPING WARM FRONT LIFTS INTO THE AREA AND PROVIDES A GOOD
FOCUSING MECHANISM FOR THE INCREASINGLY MOIST AIR. BY DAWN SATURDAY
THE DEEPENING SFC LOW OVER THE LOWER MISSISSIPPI VALLEY WILL LIFT ITS
WARM FRONT NORTH OF THE AREA PLACING OUR AREA IN THE WARM SECTOR OF A
RAPIDLY DEVELOPING SYSTEM TO THE WEST. AS A RESULT...WINDS WILL
INCREASE STEADILY DURING THE DAY SATURDAY WITH ENOUGH INSTABILITY
AVAILABLE FOR A RISK OF THUNDER ACROSS THE ENTIRE AREA...POSSIBLY
ARRIVING BEFORE DAWN SATURDAY PER THE LATEST SWODY1. A BREEZY AND
MILD DAY ENSUES AHEAD OF THE SYSTEM/S COLD FRONT LATER SATURDAY WITH
DRY WEATHER EXPECTED FOR A GOOD PORTION OF THE TIME...THOUGH SOME
SCATTERED SHOWERS AND POSSIBLE THUNDERSTORMS WILL BE AROUND EASTERN
KENTUCKY INTO SATURDAY EVENING. WILL HIT THE THUNDER CHANCES AND THE
BREEZY CONDITIONS HARDER IN THE HWO TO BE ISSUED LATER THIS MORNING.
USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPS...TD...AND WINDS
THROUGH 21Z FRIDAY AND THEN THE SUPERBLEND THROUGH 00Z SUNDAY. ONLY
SLIGHTLY TWEAKED POINT TEMPERATURE DATA FOR MAXES AND MINS. AS FOR
POPS...FAVORED A BLEND OF THE HRRR AND NAM12 EARLY THEN MAINLY THE
NAM12 THROUGH TONIGHT AND SATURDAY. ON THE WHOLE...ENDED UP SIMILAR
TO THE MOS BLEND WITH POPS THROUGH THE SHORT TERM...BUT DETAILS WHERE
ADDED TO SHOW SOME BREAKS WITHIN THE WARM SECTOR DRY SLOTTING
EXPECTED ON SATURDAY.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 357 AM EST FRI JAN 2 2015
THE EXTENDED FORECAST PERIOD BEGINS ON SATURDAY NIGHT WITH AN
AMPLIFIED UPPER LEVEL PATTERN OVER THE CONUS. A LARGE LONGWAVE
TROUGH MOVES THROUGH THE CENTRAL PAINS AND INTO THE MS RIVER VALLEY.
AT THIS TIME A POTENT SHORT WAVE IS LIFTING OUT OF THE MID MS RIVER
VALLEY AND MOVING INTO THE OH VALLEY...WHILE A SECOND STRONG
SHORTWAVE DEVELOPS ALONG THE LOWER PORTION OF THE MS VALLEY AND
QUICK LIFTS NORTHEAST AS WELL INTO THE LOWER APPALACHIAN RANGE. A
STRONG JET DEVELOPING IN THE UPPER LEVELS ON SUNDAY NIGHT OVER THE
MID ATLANTIC WILL LIFT THE UPPER LEVEL TROUGH NORTHEAST INTO THE NEW
ENGLAND AREA. THIS SETS THE PATTERN FROM MONDAY THROUGH THURSDAY OF
A SEMI PERMANENT UPPER LEVEL LONGWAVE TROUGH OVER THE GREAT LAKES
AND NEW ENGLAND AREA. THIS CYCLONIC FLOW OVER THE NORTHEASTERN CONUS
WILL LEAD TO NORTHWEST FLOW FOR EASTERN KENTUCKY THROUGH THE REST OF
THE EXTENDED.
CLOSER TO THE SURFACE FOR THE FRONT MOVING THROUGH SAT NIGHT THROUGH
SUNDAY NIGHT...THE INHERITED FORECAST AND RESULT OF THE BLEND OF
MODELS LEAVES QUITE A BIT OF PRECIP MOVING THROUGH SAT NIGHT THROUGH
SUNDAY. PWATS DURING THIS TIME WITH MODEL SOUNDINGS SHOW 1.34 INCHES
WHICH IS AMPLE THIS TIME OF YEAR. HPC RESULTS ALONG WITH THE MODEL
BLEND PUT AROUND AN INCH IN THE AREA FOR THE STA NIGHT AND SUNDAY
TIME FRAME AND HAVE GONE WITH THESE VALUES AS THOUGH...WEAKENING THE
SHOWERS WITH THE FRONT MOVING THROUGH COULD PRODUCE SOME DECENT
RAINFALL AT TIMES. AS MENTIONED WITH THE LOW SHOWING A WEAKENING
TREND...THERE IS A DECENT AMOUNT OF ISENTROPIC LIFT AHEAD AND WITH
THIS FRONT AND WITH THE INHERITED FORECAST COUPLED WITH A CONSENSUS
OF NEIGHBORING OFFICES...DECIDED TO KEEP A SLIGHT CHANCE OF THUNDER
IN THE SATURDAY NIGHT PORTION. AS MENTIONED WITH THE PROGRESSIVE
FLOW AND QUICK EXIT OF THIS FEATURE...PRECIP HANGING UP ON THE
EASTERN RIDGES SHOULD BE SHORT IN DURATION AND HAVE ALL POPS
EXITING EARLY SUNDAY NIGHT. AS SUCH...THE MOISTURE WILL EXIT THE
AREA BEFORE ANY COLD AIR FILTERS IN. ANY CHANGE OVER TO SNOW ACROSS
THE AREA IS NOT EXPECTED.
THE DRIER NORTHWEST FLOW SETTING UP BY TUESDAY WILL HINDER PRECIP
MAKING IT FAR ENOUGH SOUTH INTO EASTERN KENTUCKY FOR SNOWFALL. BASED
ON INHERITED FORECAST...PATTERN RECOGNITION AND COLLABORATION WITH
THE NEIGHBORING OFFICES...HAVE GONE DRY WITH THE WEAK SHORTWAVE
MOVING THROUGH THE OH VALLEY TUESDAY NIGHT INTO WEDNESDAY. WHILE A
FEW FLURRIES ARE POSSIBLE AS WELL...THE GENERAL TREND WITH THIS IS
THAT AS MOISTURE STARVED AS THESE CLIPPER SYSTEMS ARE...THE BULK OF
THE UPPER LEVEL SUPPORT STAYS TO THE NORTH WITH THIS WAVE. AFTER
SUNDAY NIGHT...HAVE GONE DRY OVER EASTERN KENTUCKY FOR THE REST OF
THE FORECAST. THE DEW POINTS WITH THIS ARCTIC AIR MASS MOVING IN
DURING THE LAST PART OF THE EXTENDED IS QUITE IMPRESSIVE. QUITE A
COLD AND DRY AIR MASS MAKES ITS PRESENCE KNOWN DIVING SOUTH INTO THE
CENTRAL CONUS AND MEANDERING SOUTHEAST BY THE END OF THE EXTENDED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 715 AM EST FRI JAN 2 2015
CIGS HAVE FALLEN TO MVFR IN THE SOUTHERN PARTS OF THE AREA UP TO JKL
AND NOW SJS. THESE WILL STAY LOW THROUGH THE REMAINDER OF THE TAF
PERIOD AS THE LOW LEVELS OF THE ATMOSPHERE FURTHER SATURATE. LIGHT
PCPN WILL AFFECT THE AREA THIS MORNING...FALLING MOSTLY AS RAIN...
HOWEVER SOME SLEET WILL BE POSSIBLE AT THE ONSET. EXPECT MVFR CLOUDS
TO OVERTAKE THE REST OF THE AREA FROM SOUTH TO NORTH THROUGH THE
MORNING...WITH LOCATIONS NORTH OF THE I-64 CORRIDOR LIKELY STAYING
LOW VFR UNTIL THIS AFTERNOON WHEN A DEVELOPING WARM FRONT LIFTS INTO
THIS PART OF KENTUCKY FROM THE SOUTH. LOWER CIGS IN THE IFR OR LIFR
RANGE ARE EXPECTED TONIGHT ALONG WITH RAIN AND BR LEADING TO VIS
RESTRICTIONS. SOUTHWEST WINDS OF 5 TO 10 KTS CAN BE EXPECTED THROUGH
THE DAY WITH AN INCREASE IN SPEEDS JUST OFF THE SFC TONIGHT FROM THE
SOUTHWEST. HAVE ADDED LLWS FOR THIS AT UP TO 35 KTS AT 1500 FEET TO
ALL THE TAFS STARTING AT EARLY AS 6Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
357 AM EST FRI JAN 2 2015
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 340 AM EST FRI JAN 2 2015
08Z SFC ANALYSIS SHOWS HIGH PRESSURE FADING OVER EASTERN KENTUCKY IN
ADVANCE OF A DEVELOPING WX SYSTEM TO THE SOUTHWEST AND AN AREA OF LOW
PRESSURE OFF TO THE NORTHEAST. THE CLOUDS ASSOCIATED WITH THE
SOUTHWEST SYSTEM HAVE OVERSPREAD THE AREA WITH POCKETS OF LIGHT PCPN
SHOWING UP ON THE REGIONAL RADAR...MAINLY SOUTH OF THE STATE
BORDER...THOUGH SOME RETURNS HAVE DEVELOPED ALONG INTERSTATE 64 IN
CENTRAL KENTUCKY...IN LINE WITH THE LATEST HRRR. THROUGH EAST
KENTUCKY TEMPERATURES ARE FAIRLY UNIFORM IN THE MID 30S WHILE
DEWPOINTS ARE GENERALLY IN THE MID 20S. DEW POINT DEPRESSIONS ON THE
ORDER OF 10 DEGREES WILL LEAD TO A CONCERN FOR WETBULBING WITH ANY
EARLY PCPN THIS MORNING THAT SHOULD RESULT IN PATCHES OF SLEET ALONG
WITH THE LIGHT RAIN. WILL CONTINUE TO DEPICT THIS IN THE GRIDS AND
MENTION IT IN THE HWO AND ZONES...THOUGH ANY IMPACTS ARE EXPECTED TO
BE MINIMAL GIVEN PAVEMENT TEMPERATURES ABOVE FREEZING THROUGH THE
EASTERN PARTS OF THE STATE. WINDS REMAIN LIGHT FROM THE SOUTHWEST
THROUGH THE AREA EARLY THIS MORNING.
THE MODELS ARE IN GOOD AGREEMENT ALOFT FOR THE SHORT TERM PORTION OF
THE FORECAST AS THEY ALL SHOW THE SOUTHWESTERN CLOSED LOW GETTING
PARTIALLY PICKED UP BY THE NORTHERN STREAM LATER TODAY. THIS PROCESS
RELEASES A BATCH OF ENERGY AND LOWER HEIGHTS INTO THE CENTRAL PLAINS
BY EVENING WHILE A LARGER PORTION STAYS SEPARATE OVER SOUTHERN NEW
MEXICO. THE EXPELLED NORTHERN WAVE IS QUICKLY ABSORBED INTO THE
LARGER FLOW AND SPREAD OVER THE CENTRAL GREAT LAKES BY MIDDAY
SATURDAY WHILE THE MAIN LOW IS KICKED EAST BY SOME ENERGY RIDING INTO
ITS BACKSIDE LATER SATURDAY. AHEAD OF THESE WAVES...BROAD SOUTHWEST
FLOW WILL SEND WARMER AND MORE MOIST AIR INTO THE TENNESSEE AND OHIO
VALLEYS TODAY THROUGH SATURDAY. GIVEN THE MODEL AGREEMENT HAVE
FOLLOWED THE HIGHER RESOLUTION NAM12 AND HRRR MOST CLOSELY.
SENSIBLE WEATHER WILL FEATURE THE NET RESULT OF A MOISTENING
ENVIRONMENT AND A DEVELOPING SFC LOW TO THE SOUTHWEST...RAIN CHANCES
MOVING IN FROM SOUTHWEST TO NORTHEAST TODAY. THE BETTER CHANCES
ARRIVE AFTER 18Z FOR THE BULK OF THE JKL CWA ALLOWING THE WARMER AIR
TO BRING UP TEMPERATURES WHILE DEWPOINTS CLIMB ABOVE FREEZING MAKING
ALL THE PCPN LIQUID AFTER THE EARLY MORNING POCKETS OF LIGHT MIXED
PCPN. THE REAL SURGE OF SHOWERS WILL ARRIVE LATER TONIGHT AS A
DEVELOPING WARM FRONT LIFTS INTO THE AREA AND PROVIDES A GOOD
FOCUSING MECHANISM FOR THE INCREASINGLY MOIST AIR. BY DAWN SATURDAY
THE DEEPENING SFC LOW OVER THE LOWER MISSISSIPPI VALLEY WILL LIFT ITS
WARM FRONT NORTH OF THE AREA PLACING OUR AREA IN THE WARM SECTOR OF A
RAPIDLY DEVELOPING SYSTEM TO THE WEST. AS A RESULT...WINDS WILL
INCREASE STEADILY DURING THE DAY SATURDAY WITH ENOUGH INSTABILITY
AVAILABLE FOR A RISK OF THUNDER ACROSS THE ENTIRE AREA...POSSIBLY
ARRIVING BEFORE DAWN SATURDAY PER THE LATEST SWODY1. A BREEZY AND
MILD DAY ENSUES AHEAD OF THE SYSTEM/S COLD FRONT LATER SATURDAY WITH
DRY WEATHER EXPECTED FOR A GOOD PORTION OF THE TIME...THOUGH SOME
SCATTERED SHOWERS AND POSSIBLE THUNDERSTORMS WILL BE AROUND EASTERN
KENTUCKY INTO SATURDAY EVENING. WILL HIT THE THUNDER CHANCES AND THE
BREEZY CONDITIONS HARDER IN THE HWO TO BE ISSUED LATER THIS MORNING.
USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPS...TD...AND WINDS
THROUGH 21Z FRIDAY AND THEN THE SUPERBLEND THROUGH 00Z SUNDAY. ONLY
SLIGHTLY TWEAKED POINT TEMPERATURE DATA FOR MAXES AND MINS. AS FOR
POPS...FAVORED A BLEND OF THE HRRR AND NAM12 EARLY THEN MAINLY THE
NAM12 THROUGH TONIGHT AND SATURDAY. ON THE WHOLE...ENDED UP SIMILAR
TO THE MOS BLEND WITH POPS THROUGH THE SHORT TERM...BUT DETAILS WHERE
ADDED TO SHOW SOME BREAKS WITHIN THE WARM SECTOR DRY SLOTTING
EXPECTED ON SATURDAY.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 357 AM EST FRI JAN 2 2015
THE EXTENDED FORECAST PERIOD BEGINS ON SATURDAY NIGHT WITH AN
AMPLIFIED UPPER LEVEL PATTERN OVER THE CONUS. A LARGE LONGWAVE
TROUGH MOVES THROUGH THE CENTRAL PAINS AND INTO THE MS RIVER VALLEY.
AT THIS TIME A POTENT SHORT WAVE IS LIFTING OUT OF THE MID MS RIVER
VALLEY AND MOVING INTO THE OH VALLEY...WHILE A SECOND STRONG
SHORTWAVE DEVELOPS ALONG THE LOWER PORTION OF THE MS VALLEY AND
QUICK LIFTS NORTHEAST AS WELL INTO THE LOWER APPALACHIAN RANGE. A
STRONG JET DEVELOPING IN THE UPPER LEVELS ON SUNDAY NIGHT OVER THE
MID ATLANTIC WILL LIFT THE UPPER LEVEL TROUGH NORTHEAST INTO THE NEW
ENGLAND AREA. THIS SETS THE PATTERN FROM MONDAY THROUGH THURSDAY OF
A SEMI PERMANENT UPPER LEVEL LONGWAVE TROUGH OVER THE GREAT LAKES
AND NEW ENGLAND AREA. THIS CYCLONIC FLOW OVER THE NORTHEASTERN CONUS
WILL LEAD TO NORTHWEST FLOW FOR EASTERN KENTUCKY THROUGH THE REST OF
THE EXTENDED.
CLOSER TO THE SURFACE FOR THE FRONT MOVING THROUGH SAT NIGHT THROUGH
SUNDAY NIGHT...THE INHERITED FORECAST AND RESULT OF THE BLEND OF
MODELS LEAVES QUITE A BIT OF PRECIP MOVING THROUGH SAT NIGHT THROUGH
SUNDAY. PWATS DURING THIS TIME WITH MODEL SOUNDINGS SHOW 1.34 INCHES
WHICH IS AMPLE THIS TIME OF YEAR. HPC RESULTS ALONG WITH THE MODEL
BLEND PUT AROUND AN INCH IN THE AREA FOR THE STA NIGHT AND SUNDAY
TIME FRAME AND HAVE GONE WITH THESE VALUES AS THOUGH...WEAKENING THE
SHOWERS WITH THE FRONT MOVING THROUGH COULD PRODUCE SOME DECENT
RAINFALL AT TIMES. AS MENTIONED WITH THE LOW SHOWING A WEAKENING
TREND...THERE IS A DECENT AMOUNT OF ISENTROPIC LIFT AHEAD AND WITH
THIS FRONT AND WITH THE INHERITED FORECAST COUPLED WITH A CONSENSUS
OF NEIGHBORING OFFICES...DECIDED TO KEEP A SLIGHT CHANCE OF THUNDER
IN THE SATURDAY NIGHT PORTION. AS MENTIONED WITH THE PROGRESSIVE
FLOW AND QUICK EXIT OF THIS FEATURE...PRECIP HANGING UP ON THE
EASTERN RIDGES SHOULD BE SHORT IN DURATION AND HAVE ALL POPS
EXITING EARLY SUNDAY NIGHT. AS SUCH...THE MOISTURE WILL EXIT THE
AREA BEFORE ANY COLD AIR FILTERS IN. ANY CHANGE OVER TO SNOW ACROSS
THE AREA IS NOT EXPECTED.
THE DRIER NORTHWEST FLOW SETTING UP BY TUESDAY WILL HINDER PRECIP
MAKING IT FAR ENOUGH SOUTH INTO EASTERN KENTUCKY FOR SNOWFALL. BASED
ON INHERITED FORECAST...PATTERN RECOGNITION AND COLLABORATION WITH
THE NEIGHBORING OFFICES...HAVE GONE DRY WITH THE WEAK SHORTWAVE
MOVING THROUGH THE OH VALLEY TUESDAY NIGHT INTO WEDNESDAY. WHILE A
FEW FLURRIES ARE POSSIBLE AS WELL...THE GENERAL TREND WITH THIS IS
THAT AS MOISTURE STARVED AS THESE CLIPPER SYSTEMS ARE...THE BULK OF
THE UPPER LEVEL SUPPORT STAYS TO THE NORTH WITH THIS WAVE. AFTER
SUNDAY NIGHT...HAVE GONE DRY OVER EASTERN KENTUCKY FOR THE REST OF
THE FORECAST. THE DEW POINTS WITH THIS ARCTIC AIR MASS MOVING IN
DURING THE LAST PART OF THE EXTENDED IS QUITE IMPRESSIVE. QUITE A
COLD AND DRY AIR MASS MAKES ITS PRESENCE KNOWN DIVING SOUTH INTO THE
CENTRAL CONUS AND MEANDERING SOUTHEAST BY THE END OF THE EXTENDED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 100 AM EST FRI JAN 2 2015
CLOUDS WILL GRADUALLY LOWER THROUGH THE NIGHT...WITH LIGHT
PRECIPITATION THREATENING TOWARD DAWN MAINLY ALONG AND SOUTH OF THE
HAL ROGERS PARKWAY. THIS WILL FALL AS MOSTLY LIGHT RAIN...HOWEVER
SOME SLEET IS ALSO POSSIBLE AT ONSET. EXPECT MVFR CLOUDS TO MOVE
OVER THE SOUTH BETWEEN 09 AND 12Z...AND THEN GRADUALLY OVERTAKE MORE
OF THE AREA FROM SOUTH TO NORTHWARD THROUGH THE DAY FRIDAY...WITH
LOCATIONS ALONG AND NORTH OF THE I-64 CORRIDOR LIKELY STAYING VFR
UNTIL LATER FRIDAY AFTERNOON WHEN A DEVELOPING WARM FRONT LIFT INTO
THE AREA FROM THE SOUTH. SOUTHWEST WINDS OF 5 TO 10 KTS CAN BE
EXPECTED THROUGH THE REST OF THE NIGHT AND INTO THE DAY FRIDAY.
HOWEVER...LOCATIONS ALONG THE I-64 CORRIDOR WILL LIKELY MAINTAIN
SPEEDS 10 KTS BEFORE DIMINISHING TOWARDS DAWN.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
120 AM EST FRI JAN 2 2015
.UPDATE...
ISSUED AT 120 AM EST FRI JAN 2 2015
THE CURRENT FORECAST IS ON TRACK FROM THE LAST UPDATED WITH THE HRRR
AND 00Z NAM12 KEEPING THE CWA PRETTY MUCH DRY THROUGH THE REST OF
THE NIGHT. HAVE JUST FINE TUNED TEMPS AND DEW POINTS PER THE LATEST
OBS...TRENDS...AND CONSSHORT GUIDANCE. THESE UPDATES HAVE BEEN SENT
TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 1116 PM EST THU JAN 1 2015
TEMPERATURES HAVE BEEN WARMING IN MOST OF THE VALLEY LOCATIONS THIS
EVENING...AS CLOUDS AND SOUTHWEST TO WEST SOUTHWEST WINDS HAVE BEEN
KEEPING THINGS MIXED...MORE TYPICAL OF THE DAYTIME BOUNDARY LAYER
PROCESS. PRECIPITATION CHANCES ARE TRENDING DRIER IN THE MODELS
THROUGH FRIDAY MORNING. HAVE REDUCED POPS BACK TO SLIGHT CHANCE
WITHIN THE CUMBERLAND VALLEY. GIVEN THE DRIER AIR IN PLACE...WILL
STILL ALLOW FOR A SLIGHT CHANCE OF SLEET...HOWEVER DO NOT EXPECT THIS
TO BE MUCH OF AN IMPACT AS IT WILL BE VERY LIGHT...AND GROUND
TEMPERATURES SHOULD REMAIN ABOVE FREEZING. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 731 PM EST THU JAN 1 2015
MOISTURE IS ON ITS WAY IN AS EVIDENT BY THE LIGHT RADAR RETURNS
CURRENTLY SHOWING UP ACROSS WESTERN TN/KY. TEMPERATURES ACROSS THE
SOUTHERN PORTION ARE RANGING FROM 36 TO 41 DEGREES...WITH DEW POINTS
RUNNING FROM THE MID TEENS TO THE MID 20S. THE CURRENT SHORT RANGE
MODELS CONTINUE TO SUPPORT SOME LIGHT PRECIP SKIMMING THE KY/TN
BORDER THROUGH THE OVERNIGHT...FALLING AS LIGHT RAIN/SLEET/FREEZING
RAIN DEPENDING ON HOW QUICKLY THE COLUMN SATURATES. INITIALLY...THE
DEW POINTS WILL MOST LIKELY COME UP FASTER THAN THE TEMPERATURE DROPS
OFF. THIS MAY KEEP THE FREEZING RAIN POTENTIAL LOWER SINCE GROUND
TEMPERATURES ARE GENERALLY IN THE UPPER 30S. FURTHER NORTH...SKIES
HAVE PARTIALLY CLEARED THROUGH EARLY THIS EVENING...WITH A FEW
VALLEYS ALREADY CLOSE IF NOT DROPPING BELOW FORECAST LOWS. WILL ALLOW
FROM SOME MID 20S IN THE SHELTERED VALLEYS IN THE NORTHEAST...WHERE
THICKER CLOUDS WILL LIKELY HOLD OFF FOR ANOTHER FEW HOURS. THE MODELS
CONTINUE TO SHOW A LITTLE SURGE OF PRECIP COMING IN FROM NORTH
CENTRAL KENTUCKY TOWARDS DAWN. THIS APPEARS TO BE ASSOCIATED WITH A
SMALL POCKET OF UPPER LEVEL DIVERGENCE. THE HRRR SHOWS ONLY WEAK
RETURNS MAKING IT IN TO OUR NORTH TOWARDS DAWN...AND ANYTHING THAT
DOES MAKE IT TO THE GROUND WOULD LIKELY BE IN THE FORM OF SLEET BASED
ON THE FORECAST SOUNDINGS. WILL MAINTAIN THE DRY FORECAST FOR THE
NORTH FOR NOW AND REASSESS ONCE THE 00Z DATA COMES IN. UPDATES WILL
BE FORTHCOMING.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 348 PM EST THU JAN 1 2015
HIGH PRESSURE WILL GIVE WAY TO AN ADVANCING STORM SYSTEM OVER THE
NEXT 36 HOURS. A WARM FRONT WILL PASS THROUGH OUR REGION FRIDAY
NIGHT BRINGING STRONG RAIN CHANCES. BEFORE THAT HAPPENS...WEAK
OVERRUNNING WILL CAUSE CLOUDS TO ADVANCE BACK TO THE NORTH TONIGHT
AND THEN LOWER DURING THE DAY FRIDAY AS THE AIR MASS MOISTENS FROM
THE TOP DOWN. FORECAST MODELS CONTINUE TO INDICATE THE POSSIBILITY
OF SOME LIGHT PRECIP BREAKING OUT LATE TONIGHT INTO EARLY FRIDAY
MORNING. BEST CHANCES FOR THAT HAPPENING ARE ALONG THE TENNESSEE
BORDER...BUT SOME SPOTTY PRECIP MAY SNEAK NORTHWARD EARLY SATURDAY
MORNING. WILL ADVERTISE A MIX OF LIGHT RAIN AND SLEET WITH SOME
SPOTTY FREEZING RAIN WHERE FORECAST TEMPS FLIRT WITH FREEZING...
ALTHOUGH PROBABILITY OF OCCURRENCE OF ANY PRECIP IS LOW (GENERALLY
ONLY 20 TO 30 PERCENT). RAIN CHANCES RAMP UP FRIDAY AFTERNOON AND
FRIDAY NIGHT AFTER SURFACE TEMPS WARM WELL ABOVE FREEZING ENDING ANY
THREAT FOR WINTRY PRECIP. DECIDED TO REMOVE ANY MENTION OF FREEZING
RAIN FROM THE FORECAST NORTH OF I-64 LATE FRIDAY NIGHT FIGURING
SURFACE TEMPS WILL HAVE A HARD TIME FALLING BACK TOWARD FREEZING
WITH SOUTHERLY FLOW/WARM ADVECTION IN PLACE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 348 PM EST THU JAN 1 2015
MODELS ARE STILL IN DECENT AGREEMENT STARTING OUT THE EXTENDED
PORTION OF THE FORECAST. BY SATURDAY MORNING...MODELS ARE CONTINUING
TO DEPICT PARTIAL PHASING OF THE NORTHERN AND SOUTHERN STREAMS OVER
NORTH AMERICA. A CLOSED LOW WHICH IS EXPECTED TO BE IN NEW MEXICO
AND NORTHERN TX WILL BE THE MAIN FOCUS OF CONCERN AS WE START OUT
THE FORECAST. THIS LOW WILL SHIFT NEWARD AND LOSE CONSIDERABLE
STRENGTH AS IT MOVES JUST N OF THE OHIO RIVER VALLEY THROUGH SUNDAY
MORNING. AFTER IT PASSES...MUCH OF THE CENTRAL CONUS WILL BE LEFT IN
A GENERAL TROUGHING PATTERN...WITH MUCH OF KY IN A STRONG PRESSURE
GRADIENT ON THE LEEWARD SIDE OF THE TROUGH AT 12Z SUNDAY WITH SW
FLOW. AS THE THROUGH SHIFTS EASTWARD...HEIGHTS WILL RAPIDLY DECREASE
ACROSS KY THROUGH SUNDAY EVENING...THOUGH THE TROUGH ITSELF DOES
SHOW SIGNS OF BROADENING OUT. MODELS ARE SURPRISINGLY STILL IN GOOD
AGREEMENT AS THE AXIS OF THIS TROUGH PASSES OVER KY SUNDAY NIGHT AND
MONDAY...BEFORE HEIGHTS FINALLY START RISING AGAIN ON THE BACK END
MONDAY NIGHT AND ON. IT APPEARS AS THOUGH THE LOW RESPONSIBLE FOR
THIS TROUGH /OVER NE CANADA/ WILL SLOW ITS PROPAGATION...SO THE RISE
IN HEIGHTS WILL BE MUCH SLOWER AND CONTINUE THROUGH THE REMAINDER OF
THE EXTENDED...COMPARED TO HOW QUICKLY THEY DECREASED AS THE TROUGH
NEARED KY.
A SURFACE LOW WILL PROCEED THE CLOSED LOW THAT IS EXPECTED TO MOVE
JUST NORTH OF KY. MODELS CONTINUE TO DEPICT DECENT OVERRUNNING AS
THE SURFACE LOW GRAZES THE WESTERN PORTION OF KY ON ITS TRACK NEWARD
DURING THE DAY SATURDAY. THIS OVERRUNNING...IN ADDITION TO A GOOD
SOUTHERLY FLOW OF MOISTURE FROM THE GULF OF MEXICO...WILL LEAD TO
WIDESPREAD MODERATE PRECIP ACROSS THE REGION. KY WILL ORIGINALLY
FIND ITSELF IN THE WARM SECTOR OF THIS SYSTEM AT 12Z SATURDAY...WITH
SW FLOW BRINGING IN WARMER TEMPS IN THE LOW...MID AND UPPER LEVELS.
THIS STILL SUPPORTS AN IMPRESSIVE WARM NOSE DEVELOPING...SUGGESTING
THAT MOST OF THE PRECIP WILL FALL AS RAIN. TEMPERATURES WERE RAISED
A DEGREE OR TWO IN THE NORTH...SO REMOVED ANY MENTION OF FREEZING
RAIN OR SNOW FOR 12Z SATURDAY. GIVEN HOW FAST THE SYSTEM IS TRACKING
ACROSS KY...AND THE RAPID DECREASE IN HEIGHTS ALOFT...IN ADDITION TO
WARMER TEMPS AND STRONG SW FLOW...WILL CONTINUE WITH MENTION OF
POSSIBLE THUNDERSTORMS SATURDAY AFTERNOON AND NIGHT...MAINLY DURING
THE HEAVIEST RAIN. BY SUNDAY MORNING...THE SURFACE SYSTEM WILL HAVE
PASSED EAST OF THE REGION...WHILE LOSING CONSIDERABLE STRENGTH
ALOFT. THE TROUGHING PATTERN OVER THE CONUS...HOWEVER...WILL LEAVE
SW FLOW IN PLACE...SO WILL KEEP WITH CHANCES OF RAIN SATURDAY NIGHT
AND DURING THE DAY SUNDAY.
WINDS AT THIS POINT WILL THEN SWITCH TO A MORE WRLY DIRECTION IN THE
MID AND UPPER LEVELS...WITH MUCH DRIER AIR USHERING IN. CONTINUED
LOW LEVEL WRAP AROUND MOISTURE IS STILL POSSIBLE THROUGH SUNDAY
EVENING...BUT WILL QUICKLY TAPER OFF. UPSLOPE FLOW WILL KEEP POPS IN
SLIGHTLY LONGER ACROSS THE HIGHER TERRAIN IN THE SE. THIS WILL BE
THE POINT WHEN THE UPPER LEVEL TROUGH AXIS IS MOVING ACROSS AND JUST
EAST OF THE REGION...WITH MUCH COLDER AIR USHERING INTO THE REGION.
AS A RESULT...PREVIOUS FORECAST HAD LINGERING RAIN CHANGING OVER TO
SNOW SUNDAY EVENING. HOWEVER...IT SEEMS AS THOUGH MODELS ARE
TRENDING THE POPS OUT SLIGHTLY FASTER NOW...SO EXPECT THAT BELOW
FREEZING TEMPS WON/T PLAY MUCH OF A CONCERN SINCE PRECIP WILL BE OUT
OF THE AREA BEFORE IT TAKES AFFECT. KEPT ANY PRECIP SUNDAY EVENING
AS RAIN BEFORE TAPERING OFF.
RISING HEIGHTS AND SURFACE HIGH PRESSURE SHOULD KEEP MOST OF THE
CONCERN FOR FURTHER PRECIP OUT OF THE REGION THROUGH MIDWEEK WHILE
TEMPERATURES STAY WELL BELOW NORMAL. SEVERAL SHORTWAVES WILL LIKELY
QUICKLY PASS ALONG THE LONGWAVE TROUGH AXIS...BRINGING THE THREAT OF
SHORT LIVED SHOTS OF PRECIP THROUGH THE LAST PART OF THE FORECAST.
THE FIRST OF THESE WILL BE TUESDAY NIGHT...WITH SOME POSSIBILITY
THAT THE PRECIP COULD GRAZE OUR FAR NORTHERN COUNTIES IN THE FORM OF
A QUICK LIGHT SNOW. ANOTHER ONE MAY IMPACT THE REGION WEDNESDAY
NIGHT INTO THURSDAY AS WELL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 100 AM EST FRI JAN 2 2015
CLOUDS WILL GRADUALLY LOWER THROUGH THE NIGHT...WITH LIGHT
PRECIPITATION THREATENING TOWARD DAWN MAINLY ALONG AND SOUTH OF THE
HAL ROGERS PARKWAY. THIS WILL FALL AS MOSTLY LIGHT RAIN...HOWEVER
SOME SLEET IS ALSO POSSIBLE AT ONSET. EXPECT MVFR CLOUDS TO MOVE
OVER THE SOUTH BETWEEN 09 AND 12Z...AND THEN GRADUALLY OVERTAKE MORE
OF THE AREA FROM SOUTH TO NORTHWARD THROUGH THE DAY FRIDAY...WITH
LOCATIONS ALONG AND NORTH OF THE I-64 CORRIDOR LIKELY STAYING VFR
UNTIL LATER FRIDAY AFTERNOON WHEN A DEVELOPING WARM FRONT LIFT INTO
THE AREA FROM THE SOUTH. SOUTHWEST WINDS OF 5 TO 10 KTS CAN BE
EXPECTED THROUGH THE REST OF THE NIGHT AND INTO THE DAY FRIDAY.
HOWEVER...LOCATIONS ALONG THE I-64 CORRIDOR WILL LIKELY MAINTAIN
SPEEDS 10 KTS BEFORE DIMINISHING TOWARDS DAWN.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...ABE
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1116 PM EST THU JAN 1 2015
.UPDATE...
ISSUED AT 1116 PM EST THU JAN 1 2015
TEMPERATURES HAVE BEEN WARMING IN MOST OF THE VALLEY LOCATIONS THIS
EVENING...AS CLOUDS AND SOUTHWEST TO WEST SOUTHWEST WINDS HAVE BEEN
KEEPING THINGS MIXED...MORE TYPICAL OF THE DAYTIME BOUNDARY LAYER
PROCESS. PRECIPITATION CHANCES ARE TRENDING DRIER IN THE MODELS
THROUGH FRIDAY MORNING. HAVE REDUCED POPS BACK TO SLIGHT CHANCE
WITHIN THE CUMBERLAND VALLEY. GIVEN THE DRIER AIR IN PLACE...WILL
STILL ALLOW FOR A SLIGHT CHANCE OF SLEET...HOWEVER DO NOT EXPECT THIS
TO BE MUCH OF AN IMPACT AS IT WILL BE VERY LIGHT...AND GROUND
TEMPERATURES SHOULD REMAIN ABOVE FREEZING. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 731 PM EST THU JAN 1 2015
MOISTURE IS ON ITS WAY IN AS EVIDENT BY THE LIGHT RADAR RETURNS
CURRENTLY SHOWING UP ACROSS WESTERN TN/KY. TEMPERATURES ACROSS THE
SOUTHERN PORTION ARE RANGING FROM 36 TO 41 DEGREES...WITH DEW POINTS
RUNNING FROM THE MID TEENS TO THE MID 20S. THE CURRENT SHORT RANGE
MODELS CONTINUE TO SUPPORT SOME LIGHT PRECIP SKIMMING THE KY/TN
BORDER THROUGH THE OVERNIGHT...FALLING AS LIGHT RAIN/SLEET/FREEZING
RAIN DEPENDING ON HOW QUICKLY THE COLUMN SATURATES. INITIALLY...THE
DEW POINTS WILL MOST LIKELY COME UP FASTER THAN THE TEMPERATURE DROPS
OFF. THIS MAY KEEP THE FREEZING RAIN POTENTIAL LOWER SINCE GROUND
TEMPERATURES ARE GENERALLY IN THE UPPER 30S. FURTHER NORTH...SKIES
HAVE PARTIALLY CLEARED THROUGH EARLY THIS EVENING...WITH A FEW
VALLEYS ALREADY CLOSE IF NOT DROPPING BELOW FORECAST LOWS. WILL ALLOW
FROM SOME MID 20S IN THE SHELTERED VALLEYS IN THE NORTHEAST...WHERE
THICKER CLOUDS WILL LIKELY HOLD OFF FOR ANOTHER FEW HOURS. THE MODELS
CONTINUE TO SHOW A LITTLE SURGE OF PRECIP COMING IN FROM NORTH
CENTRAL KENTUCKY TOWARDS DAWN. THIS APPEARS TO BE ASSOCIATED WITH A
SMALL POCKET OF UPPER LEVEL DIVERGENCE. THE HRRR SHOWS ONLY WEAK
RETURNS MAKING IT IN TO OUR NORTH TOWARDS DAWN...AND ANYTHING THAT
DOES MAKE IT TO THE GROUND WOULD LIKELY BE IN THE FORM OF SLEET BASED
ON THE FORECAST SOUNDINGS. WILL MAINTAIN THE DRY FORECAST FOR THE
NORTH FOR NOW AND REASSESS ONCE THE 00Z DATA COMES IN. UPDATES WILL
BE FORTHCOMING.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 348 PM EST THU JAN 1 2015
HIGH PRESSURE WILL GIVE WAY TO AN ADVANCING STORM SYSTEM OVER THE
NEXT 36 HOURS. A WARM FRONT WILL PASS THROUGH OUR REGION FRIDAY
NIGHT BRINGING STRONG RAIN CHANCES. BEFORE THAT HAPPENS...WEAK
OVERRUNNING WILL CAUSE CLOUDS TO ADVANCE BACK TO THE NORTH TONIGHT
AND THEN LOWER DURING THE DAY FRIDAY AS THE AIR MASS MOISTENS FROM
THE TOP DOWN. FORECAST MODELS CONTINUE TO INDICATE THE POSSIBILITY
OF SOME LIGHT PRECIP BREAKING OUT LATE TONIGHT INTO EARLY FRIDAY
MORNING. BEST CHANCES FOR THAT HAPPENING ARE ALONG THE TENNESSEE
BORDER...BUT SOME SPOTTY PRECIP MAY SNEAK NORTHWARD EARLY SATURDAY
MORNING. WILL ADVERTISE A MIX OF LIGHT RAIN AND SLEET WITH SOME
SPOTTY FREEZING RAIN WHERE FORECAST TEMPS FLIRT WITH FREEZING...
ALTHOUGH PROBABILITY OF OCCURRENCE OF ANY PRECIP IS LOW (GENERALLY
ONLY 20 TO 30 PERCENT). RAIN CHANCES RAMP UP FRIDAY AFTERNOON AND
FRIDAY NIGHT AFTER SURFACE TEMPS WARM WELL ABOVE FREEZING ENDING ANY
THREAT FOR WINTRY PRECIP. DECIDED TO REMOVE ANY MENTION OF FREEZING
RAIN FROM THE FORECAST NORTH OF I-64 LATE FRIDAY NIGHT FIGURING
SURFACE TEMPS WILL HAVE A HARD TIME FALLING BACK TOWARD FREEZING
WITH SOUTHERLY FLOW/WARM ADVECTION IN PLACE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 348 PM EST THU JAN 1 2015
MODELS ARE STILL IN DECENT AGREEMENT STARTING OUT THE EXTENDED
PORTION OF THE FORECAST. BY SATURDAY MORNING...MODELS ARE CONTINUING
TO DEPICT PARTIAL PHASING OF THE NORTHERN AND SOUTHERN STREAMS OVER
NORTH AMERICA. A CLOSED LOW WHICH IS EXPECTED TO BE IN NEW MEXICO
AND NORTHERN TX WILL BE THE MAIN FOCUS OF CONCERN AS WE START OUT
THE FORECAST. THIS LOW WILL SHIFT NEWARD AND LOSE CONSIDERABLE
STRENGTH AS IT MOVES JUST N OF THE OHIO RIVER VALLEY THROUGH SUNDAY
MORNING. AFTER IT PASSES...MUCH OF THE CENTRAL CONUS WILL BE LEFT IN
A GENERAL TROUGHING PATTERN...WITH MUCH OF KY IN A STRONG PRESSURE
GRADIENT ON THE LEEWARD SIDE OF THE TROUGH AT 12Z SUNDAY WITH SW
FLOW. AS THE THROUGH SHIFTS EASTWARD...HEIGHTS WILL RAPIDLY DECREASE
ACROSS KY THROUGH SUNDAY EVENING...THOUGH THE TROUGH ITSELF DOES
SHOW SIGNS OF BROADENING OUT. MODELS ARE SURPRISINGLY STILL IN GOOD
AGREEMENT AS THE AXIS OF THIS TROUGH PASSES OVER KY SUNDAY NIGHT AND
MONDAY...BEFORE HEIGHTS FINALLY START RISING AGAIN ON THE BACK END
MONDAY NIGHT AND ON. IT APPEARS AS THOUGH THE LOW RESPONSIBLE FOR
THIS TROUGH /OVER NE CANADA/ WILL SLOW ITS PROPAGATION...SO THE RISE
IN HEIGHTS WILL BE MUCH SLOWER AND CONTINUE THROUGH THE REMAINDER OF
THE EXTENDED...COMPARED TO HOW QUICKLY THEY DECREASED AS THE TROUGH
NEARED KY.
A SURFACE LOW WILL PROCEED THE CLOSED LOW THAT IS EXPECTED TO MOVE
JUST NORTH OF KY. MODELS CONTINUE TO DEPICT DECENT OVERRUNNING AS
THE SURFACE LOW GRAZES THE WESTERN PORTION OF KY ON ITS TRACK NEWARD
DURING THE DAY SATURDAY. THIS OVERRUNNING...IN ADDITION TO A GOOD
SOUTHERLY FLOW OF MOISTURE FROM THE GULF OF MEXICO...WILL LEAD TO
WIDESPREAD MODERATE PRECIP ACROSS THE REGION. KY WILL ORIGINALLY
FIND ITSELF IN THE WARM SECTOR OF THIS SYSTEM AT 12Z SATURDAY...WITH
SW FLOW BRINGING IN WARMER TEMPS IN THE LOW...MID AND UPPER LEVELS.
THIS STILL SUPPORTS AN IMPRESSIVE WARM NOSE DEVELOPING...SUGGESTING
THAT MOST OF THE PRECIP WILL FALL AS RAIN. TEMPERATURES WERE RAISED
A DEGREE OR TWO IN THE NORTH...SO REMOVED ANY MENTION OF FREEZING
RAIN OR SNOW FOR 12Z SATURDAY. GIVEN HOW FAST THE SYSTEM IS TRACKING
ACROSS KY...AND THE RAPID DECREASE IN HEIGHTS ALOFT...IN ADDITION TO
WARMER TEMPS AND STRONG SW FLOW...WILL CONTINUE WITH MENTION OF
POSSIBLE THUNDERSTORMS SATURDAY AFTERNOON AND NIGHT...MAINLY DURING
THE HEAVIEST RAIN. BY SUNDAY MORNING...THE SURFACE SYSTEM WILL HAVE
PASSED EAST OF THE REGION...WHILE LOSING CONSIDERABLE STRENGTH
ALOFT. THE TROUGHING PATTERN OVER THE CONUS...HOWEVER...WILL LEAVE
SW FLOW IN PLACE...SO WILL KEEP WITH CHANCES OF RAIN SATURDAY NIGHT
AND DURING THE DAY SUNDAY.
WINDS AT THIS POINT WILL THEN SWITCH TO A MORE WRLY DIRECTION IN THE
MID AND UPPER LEVELS...WITH MUCH DRIER AIR USHERING IN. CONTINUED
LOW LEVEL WRAP AROUND MOISTURE IS STILL POSSIBLE THROUGH SUNDAY
EVENING...BUT WILL QUICKLY TAPER OFF. UPSLOPE FLOW WILL KEEP POPS IN
SLIGHTLY LONGER ACROSS THE HIGHER TERRAIN IN THE SE. THIS WILL BE
THE POINT WHEN THE UPPER LEVEL TROUGH AXIS IS MOVING ACROSS AND JUST
EAST OF THE REGION...WITH MUCH COLDER AIR USHERING INTO THE REGION.
AS A RESULT...PREVIOUS FORECAST HAD LINGERING RAIN CHANGING OVER TO
SNOW SUNDAY EVENING. HOWEVER...IT SEEMS AS THOUGH MODELS ARE
TRENDING THE POPS OUT SLIGHTLY FASTER NOW...SO EXPECT THAT BELOW
FREEZING TEMPS WON/T PLAY MUCH OF A CONCERN SINCE PRECIP WILL BE OUT
OF THE AREA BEFORE IT TAKES AFFECT. KEPT ANY PRECIP SUNDAY EVENING
AS RAIN BEFORE TAPERING OFF.
RISING HEIGHTS AND SURFACE HIGH PRESSURE SHOULD KEEP MOST OF THE
CONCERN FOR FURTHER PRECIP OUT OF THE REGION THROUGH MIDWEEK WHILE
TEMPERATURES STAY WELL BELOW NORMAL. SEVERAL SHORTWAVES WILL LIKELY
QUICKLY PASS ALONG THE LONGWAVE TROUGH AXIS...BRINGING THE THREAT OF
SHORT LIVED SHOTS OF PRECIP THROUGH THE LAST PART OF THE FORECAST.
THE FIRST OF THESE WILL BE TUESDAY NIGHT...WITH SOME POSSIBILITY
THAT THE PRECIP COULD GRAZE OUR FAR NORTHERN COUNTIES IN THE FORM OF
A QUICK LIGHT SNOW. ANOTHER ONE MAY IMPACT THE REGION WEDNESDAY
NIGHT INTO THURSDAY AS WELL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 731 PM EST THU JAN 1 2015
CLOUDS WILL GRADUALLY LOWER AND ADVANCE NORTHWARD THROUGH THE
NIGHT...WITH LIGHT PRECIPITATION THREATENING MAINLY ALONG AND SOUTH
OF THE HAL ROGERS PARKWAY. THIS WILL FALL AS MAINLY LIGHT
RAIN...HOWEVER SOME SLEET IS ALSO POSSIBLE AT ONSET. EXPECT MVFR
CLOUDS TO MOVE IN THE SOUTH BETWEEN 06 AND 09Z...AND THEN GRADUALLY
BUILD NORTHWARD THROUGH THE DAY ON FRIDAY...WITH LOCATIONS ALONG AND
NORTH OF THE I-64 CORRIDOR LIKELY STAYING VFR UNTIL LATER FRIDAY
EVENING WHEN A WARM FRONT ADVANCES ACROSS THE AREA FROM THE SOUTH.
SOUTHWEST WINDS OF 5 TO 10 KTS...WITH LOCATIONS ALONG THE I-64
CORRIDOR MAINTAINING AROUND 10 KTS...WILL CONTINUE THROUGH THE
NIGHT BEFORE DIMINISHING TOWARDS DAWN.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...ABE
LONG TERM...JMW
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1140 PM CST THU JAN 1 2015
.AVIATION...
EXPECT LOW CIGS AND WIDESPREAD RAINFALL TO KEEP IFR CONDITIONS
PREVAILING THROUGHOUT THE 06Z TAF PD. ISOLD TSTMS WILL ALSO BE
POSSIBLE ALONG AND E OF A KLFK/KSHV/KELD LINE. WINDS WILL REMAIN
OUT OF THE NE AT 5-10 KTS FOR MUCH OF THE PD...BECOMING VRBL AFTER
SUNSET FRIDAY EVENING. /12/
&&
.PREV DISCUSSION... /ISSUED 840 PM CST THU JAN 1 2015/
DISCUSSION...
WIDESPREAD RAIN CONTINUES ACROSS THE EASTERN TWO THIRDS OF THE
REGION THIS EVENING. HAVE EVEN SEEN SOME ELEVATED THUNDERSTORMS
ACROSS OUR SOUTHERN ZONES ALONG AN ELEVATED INSTABILITY AXIS WHICH
IS SLOWLY TRYING TO ADVANCE NORTHWARD. REGIONAL RADAR MOSAICS
SHOWING SOME BREAKS IN THE COVERAGE ACROSS PORTIONS OF CENTRAL AND
NORTHEAST TEXAS. HOWEVER...OBSERVATIONS STILL SHOWING LIGHT RAIN
WITH MEASURABLE DRIZZLE ONGOING ACROSS THESE OBSERVATIONS SITES.
FOR THE UPDATE...THOUGHT ABOUT LOWERING CATEGORICAL POPS ACROSS
THE WEST OVERNIGHT WHERE THE BREAK IN THE OBSERVABLE COVERAGE
EXISTS BUT THE LATEST HRRR SUGGESTS THAT MORE DEVELOPMENT IS
POSSIBLE ACROSS CENTRAL TX AFTER MIDNIGHT...MOVING INTO OUR NE TX
ZONES. LATEST 00Z NAM OUTPUT SUPPORTS THIS REASONING AS WELL SO
TRIMMED QPF AMOUNTS BACK SOMEWHAT IN THE WEST BUT KEPT THE
CATEGORICAL WORDING. ALSO ADDED THUNDERSTORM MENTION ALONG AND
SOUTH OF A LFK/SHV/MLU LINE THROUGH THE NIGHT AS WELL.
CONCERNING OVERNIGHT TEMPS...EXPECTING VERY LITTLE CHANGE IN
TEMPERATURES THROUGH THE NIGHT. IN FACT...SINCE 4 PM...AMBIENT
TEMPS HAVE EITHER STAYED PUT OR RISEN A DEGREE OR TWO THROUGH THE
EVENING AND WOULD NOT BE SURPRISED TO SEE AN ADDITIONAL DEGREE OR
TWO CLIMB AS THE LOW LEVELS CONTINUE TO WARM. MADE THIS CHANGE TO
THE OVERNIGHT FCST ALONG WITH DEWPOINT AND RH GRIDS.
OTHERWISE...FCST IS IN PRETTY GOOD SHAPE WITH NO OTHER ADDITIONAL
CHANGES NECESSARY...13.
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 39 44 43 55 37 / 100 90 90 90 10
MLU 39 47 45 60 40 / 100 80 90 90 20
DEQ 37 41 39 48 33 / 90 90 90 60 10
TXK 36 41 40 51 35 / 100 90 90 70 10
ELD 37 42 41 53 37 / 100 90 90 90 10
TYR 38 42 40 54 35 / 100 90 90 70 10
GGG 39 43 42 54 36 / 100 90 90 70 10
LFK 43 48 45 56 38 / 100 70 90 90 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
12
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1205 PM EST FRI JAN 2 2015
.SYNOPSIS...
AN ARCTIC FRONT WILL SWEEP ACROSS THE REGION THIS AFTERNOON. HIGH
PRESSURE WILL BUILD INTO THE AREA TONIGHT THROUGH SATURDAY. LOW
PRESSURE TRACKING NORTHWEST OF MAINE WILL ALLOW A WARM FRONT TO
APPROACH THE REGION SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1205 PM UPDATE...SNOW SQUALLS CONTINUE ACROSS EASTERN PORTIONS OF
OUR FORECAST AREA. THESE CONTINUE TO PRODUCE HEAVY SNOW AND GUSTY
WINDS. MOST PLACES WILL SEE AN INCH OF SNOW AT BEST, BUT ANYWHERE
SQUALLS STRIKE COULD SEE MORE; WE HAVE ALREADY HAD A REPORT OF 3
INCHES NEAR EASTON. SNOW SHOWERS AND SQUALLS WILL CONTINUE THROUGH
EARLY AFTERNOON; THEY SHOULD WIND DOWN AS THE COLD FRONT PASSES
THROUGH. THE EXCEPTION WILL BE OVER THE FAR NORTH WHERE STREAMERS
OFF THE SAINT LAWRENCE RIVER WILL BE POSSIBLE. HAVE MADE
ADJUSTMENTS TO POPS, SKY, AND TEMPERATURES TO MATCH CURRENT
TRENDS. ALSO BUMPED UP SNOWFALL ACCUMULATIONS FOR TODAY. NO OTHER
CHANGES WERE NEEDED.
PREVIOUS DISCUSSION...THE NAM AND LATEST HRRR 3KM WERE DOING
QUITE WELL W/THE CURRENT SETUP. THINKING HERE IS THAT THE FIRST
BATCH OF SNOW SHOWERS OCCURRING ATTM WILL MOVE ACROSS THE REGION
W/THE BEST ENHANCEMENT FROM MT. KATAHDIN TO THE SHERMAN-PATTEN
REGION AS UP TO AN INCH OR SNOW COULD ACCUMULATE. ANOTHER BATCH OF
SNOW SHOWERS AND A FEW SQUALLS LOOK LIKE THEY WILL SET UP BETWEEN
7 AM AND 10 AM THIS MORNING W/THE ARCTIC FRONT APPROACHING. THE
NAM SOUNDING SUPPORTS 850-700MBS LAPSE RATES AROUND 7.0 C/KM W/A
FCST CAPE IN THE RANGE OF 75-100 JOULES. THIS IS WHERE IS SOME
AREAS COULD PICK UP ANOTHER INCH OF SNOW W/SOME GUSTY WINDS.
FURTHER SOUTH FROM THE CENTRAL HIGHLANDS DOWN TO INTO TEH DOWNEAST
REGION, MAINLY MOSTLY CLOUDY W/A FEW FLURRIES. THINGS WIND DOWN
NEAR OR AFTER 18Z. TEMPERATURES LOOK LIKE THEY COULD ACTUALLY
CLIMB SOME THIS MORNING AHEAD OF THE FRONT AND THEN FALL BACK
SHARPLY THIS AFTERNOON INTO THE EVENING. ADJUSTMENTS WERE NEEDED
TO THE MAXES TODAY TO BRING THEM UP AND SHOW AN EARLY DAYTIME HIGH
TEMP. CLOUDS SHOULD BREAK UP THIS AFTERNOON AS THE LATEST IR
SATELLITE IMAGERY SHOWS THAT CLEARING BACK ACROSS QUEBEC AND THIS
IS SUPPORTED BY THE NAM GUIDANCE. WINDS WILL ALSO PICK UP FOR A
TIME AS THE FRONT MOVES IN.
THE CHALLENGE TONIGHT WILL BE HOW SOON THE REGION CLEARS OUT AND
HOW QUICKLY THE WINDS DROP OFF W/HIGH PRES MOVING RAPIDLY INTO
THE REGION OVERNIGHT. ANOTHER FACTOR WILL BE THE WNW FLOW COMING
OFF THE OPEN ST. LAWRENCE AS THIS AIRMASS IS QUITE COLD. SOUNDINGS
SHOW THE COLUMN TO DRY OUT THROUGH 500MBS W/THE EXCEPTION OF THE
CROWN OF MAINE AS SOME MOISTURE STAYS TRAPPED BETWEEN 925-850MBS.
DECIDED TO HANG ON TO SOME CLOUDS ACROSS THE CROWN AND WENT
W/CLEARING FOR THE REST OF THE CWA. SOMETIMES W/A SCENARIO LIKE
THIS ONE, LIGHT SNOW COULD SET UP, BUT SINCE THE AIRMASS LOOKS BE
DRY ABOVE 850MBS OVER THE CROWN, DECIDED TO STAY AWAY FROM ANY
MENTION OF LIGHT SNOW ATTM. STAYED CLOSE TO THE DAYCREW`S THINKING
OF OVERNIGHT LOWS DROPPING TO 10-15 BELOW ACROSS THE NORTH AND
CENTRAL AREAS W/SINGLE NUMBERS FOR THE DOWNEAST REGION INCLUDING
THE COAST. IF THE WINDS DROP OFF SOONER, THEN TEMPERATURES COULD
BE EVEN COLDER BY 7 AM SATURDAY. THIS CAN BE ASSESSED FURTHER BY
THE ONCOMING DAYCREW.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
SATURDAY IS SHAPING UP AS THE BETTER OF THE TWO WEEKEND DAYS AS
LONG AS YOU DONT MIND THE COLD. EXPECT PLENTY OF SUN TO START AS
HIGH PRESSURE MOVES ACROSS THE REGION. HIGH CLOUDS WILL BEGIN TO
INCREASE BY AFTERNOON. HIGH TEMPERATURES ON SATURDAY WILL ONLY
RANGE FROM THE SINGLE DIGITS TO AROUND 10 ABOVE NORTH AND CENTRAL
AREAS WITH MID TO UPPER TEENS DOWN EAST.
CLOUDS WILL CONTINUE TO INCREASE AND THICKEN SATURDAY EVENING IN
ADVANCE OF LOW PRESSURE APPROACHING FROM THE WEST. EXPECT
PRECIPITATION IN THE FORM OF SNOW TO DEVELOP FROM SOUTHWEST TO
NORTHEAST BY OR SHORTLY AFTER MIDNIGHT. WARMER AIR MOVING IN ALOFT
WILL RESULT IN THE PRECIPITATION MIXING WITH SLEET AND FREEZING
RAIN ACROSS DOWN EAST AREAS BY LATE SATURDAY NIGHT BUT THE
PRECIPITATION WILL REMAIN IN THE FORM OF ALL SNOW ACROSS NORTHERN
AND CENTRAL AREAS THROUGH THE NIGHT SATURDAY WITH SEVERAL INCHES
OF SNOW POSSIBLE BY DAYBREAK SUNDAY. LOW TEMPERATURES WILL OCCUR
EARLY IN THE EVENING SATURDAY BEFORE SLOWLY RISING OVERNIGHT.
PRECIPITATION WILL BE ONGOING FIRST THING SUNDAY AS LOW PRESSURE
CONTINUES TO TRACK TO OUR NORTHWEST. MODELS CONTINUE TO HINT AT A
WEAK TRIPLE POINT LOW FORMING ALONG THE MAINE COAST DURING SUNDAY.
AS THE PRIMARY LOW CONTINUES TO TRACK TO OUR NORTHWEST ON SUNDAY
WARMER AIR ALOFT WILL CONTINUE TO BRING MILDER AIR ALOFT WITH
PRECIPITATION CHANGE TO SLEET AND FREEZING RAIN ACROSS NORTHERN
AND CENTRAL AREAS AND EVEN ALL RAIN ACROSS DOWN EAST ESPECIALLY
THE COAST. RIGHT NOW IT APPEARS AS IF MOST AREAS WILL SEE SNOW
TOTAL RANGING FROM 3 TO 6 INCHES BEFORE THE CHANGEOVER OCCURS ON
SUNDAY. ICE ACCUMULATIONS ARE EXPECTED TO RANGE FROM ABOUT A
TENTH OF AN INCH CENTRAL AND DOWN EAST AND LESS THAN A TENTH OF AN
INCH ACROSS NORTHERN AREAS. SINCE THIS IS STILL A LATE FOURTH INTO
FIFTH PERIOD EVENT WONT BE ISSUING ANY HEADLINES YET BUT A THIS
TIME IT LOOKS LIKE WINTER WEATHER ADVISORIES WILL PROBABLY BE
NEEDED FOR JUST ABOUT ALL AREAS OF OUR CWA FOR SATURDAY NIGHT AND
SUNDAY FOR THE COMBINATION OF SNOW AND MIXED PRECIPITATION. THE
STEADY PRECIPITATION IS EXPECTED TO WIND DOWN ACROSS THE AREA AS
THE LOW CONTINUES TO TRACK TO THE NORTHEAST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
LOW PRESSURE WILL CONTINUE TO TRACK AWAY FROM THE REGION SUNDAY
NIGHT. ANY LINGERING SNOW SHOWERS OR MIXED PRECIPITATION WILL BE
DIMINISHING EARLY SUNDAY EVENING.
MUCH COLDER AIR WILL BEGIN TO POUR INTO THE REGION ON MONDAY WITH
HIGH TEMPERATURES OCCURRING EARLY IN THE DAY AND THEN FALLING IN
THE AFTERNOON. MONDAY NIGHT IS SHAPING UP AS A MAINLY CLEAR AND
BITTER COLD NIGHT WITH LOW FALLING TO 10 BELOW TO 15 BELOW ZERO
ACROSS THE NORTH AND ZERO TO 5 BELOW ZERO ACROSS CENTRAL AND DOWN
EAST. MAY NEED WIND CHILL ADVISORIES FOR NORTHERN AREAS AS WELL
AS WEST WINDS WILL MAKE IT FEEL EVEN COLDER.
TUESDAY WILL START OFF MAINLY CLEAR BEFORE CLOUDS BEGIN TO INCREASE
IN ADVANCE OF A CLIPPER TYPE SYSTEM APPROACHING FROM THE WEST.
EXPECT THE CHANCE FOR SNOW ESPECIALLY ACROSS DOWN EAST AREAS AS
THE SYSTEM MOVES EAST. THE SNOW MAY CONTINUE INTO THE FIRST PART
OF WEDNESDAY BEFORE DIMINISHING WEDNESDAY AFTERNOON.
EXPECT MAINLY DRY WEATHER WEDNESDAY NIGHT AND THURSDAY BUT
CONTINUED BELOW NORMAL TEMPERATURES.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
NEAR TERM: VFR CONDITIONS FOR THE MOST PART ACROSS THE REGION
W/TEMPO MVFR FOR THE NORTHERN TERMINALS TODAY W/SOME SNOW. WINDS
WILL PICK UP LATER THIS MORNING INTO THE AFTERNOON W/GUST
POTENTIAL ACROSS NORTHERN AREAS OF 25KTS.
SHORT TERM: VFR CONDITIONS EXPECTED ON SATURDAY. WIDESPREAD FLIGHT
RESTRICTIONS ARE EXPECTED TO DEVELOP SATURDAY NIGHT AND CONTINUE
ON SUNDAY WITH SNOW/SLEET/FREEZING RAIN EXPECTED TO AFFECT ALL
TERMINALS. R/WY SNOW ACCUMULATIONS FROM LATE SATURDAY NIGHT
THROUGH SUNDAY MAY RANGE FROM 3 TO 6 INCHES AT ALL THE TERMINALS
ALONG WITH THE POSSIBILITY OF SOME ICE ACCUMULATION ESPECIALLY
KBGR/KHUL TERMINALS. PRECIPITATION WILL BEGIN TO DIMINISH SUNDAY
EVENING WITH CONDITIONS IMPROVING TO VFR BY LATER SUNDAY NIGHT.
VFR CONDITIONS EXPECTED MONDAY. VFR MOST OF TUESDAY BUT POTENTIAL
FOR SNOW DEVELOPING LATE IN THE DAY ESPECIALLY KBGR/KBHB WITH
POSSIBLE IFR CONDITIONS BY TUE EVE.
&&
.MARINE...
NEAR TERM: A SMALL CRAFT ADVISORY REMAINS IN EFFECT THROUGH
TONIGHT W/GUSTS HITTING CLOSE TO 30 KTS. SEAS ARE RUNNING 7-10 FT
OVER THE OUTER ZONES AND THEY COULD BUILD A FEW MORE FT BEFORE
LEVELING OFF. SW WINDS WILL VEER TO THE WNW THIS AFTERNOON INTO
TONIGHT. ADJUSTMENTS WERE MADE TO THE SEAS TO ACCOUNT FOR THE
CURRENT CONDITIONS.
SHORT TERM: SMALL CRAFT ADVISORY CONDITIONS ARE POSSIBLE
SATURDAY. WINDS/SEAS WILL BRIEFLY DIMINISH EARLY SATURDAY EVENING
BEFORE INCREASING LATE SATURDAY NIGHT AND SUNDAY. A GALE WATCH
MAY BE REQUIRED FOR LATER SATURDAY NIGHT AND SUNDAY WITH CONTINUED
POTENTIAL FOR GALE FORCE WIND EARLY NEXT WEEK IN THE COLD
ADVECTION. VISIBILITY WILL BE UNRESRICTED SATURDAY AND THEN A
MILE OR LESS IN PRECIPITATION LATER SATURDAY NIGHT AND SUNDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR ANZ050>052.
&&
$$
NEAR TERM...HASTINGS/HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HASTINGS/HEWITT/DUDA
MARINE...HASTINGS/HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
917 AM EST FRI JAN 2 2015
.SYNOPSIS...
AN ARCTIC FRONT WILL SWEEP ACROSS THE REGION THIS AFTERNOON. HIGH
PRESSURE WILL BUILD INTO THE AREA TONIGHT THROUGH SATURDAY. LOW
PRESSURE TRACKING NORTHWEST OF MAINE WILL ALLOW A WARM FRONT TO
APPROACH THE REGION SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
915 AM UPDATE...WE`RE CONTINUING TO SEE SCATTERED SHOWERS ACROSS
OUR NORTHERN AREAS THIS MORNING. SOME OF THESE SHOWERS ARE BRIEFLY
HEAVY AND COULD REDUCE VISIBILITY SHARPLY AT TIMES. THIS ACTIVITY
WILL SHIFT INTO NEW BRUNSWICK THROUGH THE MORNING HOURS. IN THE
MEANTIME, A COLD FRONT LIES POISED ON OUR WESTERN BORDER.
TEMPERATURES ARE MUCH COLDER ON THE BACK SIDE OF THIS FRONT, WITH
MANY STATIONS IN SOUTHERN QUEBEC IN THE SINGLE DIGITS AT THIS
HOUR. EXPECT TEMPERATURES IN NORTHERN MAINE TO HOLD STEADY OR
PERHAPS RISE A DEGREE OR TWO OVER THE NEXT HOUR OR SO, BUT THEN
TEMPERATURES WILL DROP QUICKLY AS THE FRONT PASSES THROUGH THE
AREA. SOUTHERN MAINE WILL HAVE MORE OF A CHANCE OF WARMING A BIT
MORE BEFORE THE FRONT COMES THROUGH. WINDS WILL SWITCH TO THE
WEST NORTHWEST BEHIND THE FRONT AS WELL, WHICH WILL ALLOW FOR SOME
STREAMERS TO COME OFF THE SAINT LAWRENCE RIVER. AS SUCH, SNOW
SHOWERS WILL CONTINUE TO BE POSSIBLE OVER THE NORTHERN PORTIONS OF
THE COUNTY THROUGH THE AFTERNOON HOURS. HAVE MADE SOME SLIGHT
ADJUSTMENTS TO POPS, TEMPS, AND WINDS TO MATCH CURRENT
OBSERVATIONS AND RADAR IMAGERY. NO OTHER CHANGES WERE NEEDED.
PREVIOUS DISCUSSION...THE NAM AND LATEST HRRR 3KM WERE DOING
QUITE WELL W/THE CURRENT SETUP. THINKING HERE IS THAT THE FIRST
BATCH OF SNOW SHOWERS OCCURRING ATTM WILL MOVE ACROSS THE REGION
W/THE BEST ENHANCEMENT FROM MT. KATAHDIN TO THE SHERMAN-PATTEN
REGION AS UP TO AN INCH OR SNOW COULD ACCUMULATE. ANOTHER BATCH OF
SNOW SHOWERS AND A FEW SQUALLS LOOK LIKE THEY WILL SET UP BETWEEN
7 AM AND 10 AM THIS MORNING W/THE ARCTIC FRONT APPROACHING. THE
NAM SOUNDING SUPPORTS 850-700MBS LAPSE RATES AROUND 7.0 C/KM W/A
FCST CAPE IN THE RANGE OF 75-100 JOULES. THIS IS WHERE IS SOME
AREAS COULD PICK UP ANOTHER INCH OF SNOW W/SOME GUSTY WINDS.
FURTHER SOUTH FROM THE CENTRAL HIGHLANDS DOWN TO INTO TEH DOWNEAST
REGION, MAINLY MOSTLY CLOUDY W/A FEW FLURRIES. THINGS WIND DOWN
NEAR OR AFTER 18Z. TEMPERATURES LOOK LIKE THEY COULD ACTUALLY
CLIMB SOME THIS MORNING AHEAD OF THE FRONT AND THEN FALL BACK
SHARPLY THIS AFTERNOON INTO THE EVENING. ADJUSTMENTS WERE NEEDED
TO THE MAXES TODAY TO BRING THEM UP AND SHOW AN EARLY DAYTIME HIGH
TEMP. CLOUDS SHOULD BREAK UP THIS AFTERNOON AS THE LATEST IR
SATELLITE IMAGERY SHOWS THAT CLEARING BACK ACROSS QUEBEC AND THIS
IS SUPPORTED BY THE NAM GUIDANCE. WINDS WILL ALSO PICK UP FOR A
TIME AS THE FRONT MOVES IN.
THE CHALLENGE TONIGHT WILL BE HOW SOON THE REGION CLEARS OUT AND
HOW QUICKLY THE WINDS DROP OFF W/HIGH PRES MOVING RAPIDLY INTO
THE REGION OVERNIGHT. ANOTHER FACTOR WILL BE THE WNW FLOW COMING
OFF THE OPEN ST. LAWRENCE AS THIS AIRMASS IS QUITE COLD. SOUNDINGS
SHOW THE COLUMN TO DRY OUT THROUGH 500MBS W/THE EXCEPTION OF THE
CROWN OF MAINE AS SOME MOISTURE STAYS TRAPPED BETWEEN 925-850MBS.
DECIDED TO HANG ON TO SOME CLOUDS ACROSS THE CROWN AND WENT
W/CLEARING FOR THE REST OF THE CWA. SOMETIMES W/A SCENARIO LIKE
THIS ONE, LIGHT SNOW COULD SET UP, BUT SINCE THE AIRMASS LOOKS BE
DRY ABOVE 850MBS OVER THE CROWN, DECIDED TO STAY AWAY FROM ANY
MENTION OF LIGHT SNOW ATTM. STAYED CLOSE TO THE DAYCREW`S THINKING
OF OVERNIGHT LOWS DROPPING TO 10-15 BELOW ACROSS THE NORTH AND
CENTRAL AREAS W/SINGLE NUMBERS FOR THE DOWNEAST REGION INCLUDING
THE COAST. IF THE WINDS DROP OFF SOONER, THEN TEMPERATURES COULD
BE EVEN COLDER BY 7 AM SATURDAY. THIS CAN BE ASSESSED FURTHER BY
THE ONCOMING DAYCREW.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
SATURDAY IS SHAPING UP AS THE BETTER OF THE TWO WEEKEND DAYS AS
LONG AS YOU DONT MIND THE COLD. EXPECT PLENTY OF SUN TO START AS
HIGH PRESSURE MOVES ACROSS THE REGION. HIGH CLOUDS WILL BEGIN TO
INCREASE BY AFTERNOON. HIGH TEMPERATURES ON SATURDAY WILL ONLY
RANGE FROM THE SINGLE DIGITS TO AROUND 10 ABOVE NORTH AND CENTRAL
AREAS WITH MID TO UPPER TEENS DOWN EAST.
CLOUDS WILL CONTINUE TO INCREASE AND THICKEN SATURDAY EVENING IN
ADVANCE OF LOW PRESSURE APPROACHING FROM THE WEST. EXPECT
PRECIPITATION IN THE FORM OF SNOW TO DEVELOP FROM SOUTHWEST TO
NORTHEAST BY OR SHORTLY AFTER MIDNIGHT. WARMER AIR MOVING IN ALOFT
WILL RESULT IN THE PRECIPITATION MIXING WITH SLEET AND FREEZING
RAIN ACROSS DOWN EAST AREAS BY LATE SATURDAY NIGHT BUT THE
PRECIPITATION WILL REMAIN IN THE FORM OF ALL SNOW ACROSS NORTHERN
AND CENTRAL AREAS THROUGH THE NIGHT SATURDAY WITH SEVERAL INCHES
OF SNOW POSSIBLE BY DAYBREAK SUNDAY. LOW TEMPERATURES WILL OCCUR
EARLY IN THE EVENING SATURDAY BEFORE SLOWLY RISING OVERNIGHT.
PRECIPITATION WILL BE ONGOING FIRST THING SUNDAY AS LOW PRESSURE
CONTINUES TO TRACK TO OUR NORTHWEST. MODELS CONTINUE TO HINT AT A
WEAK TRIPLE POINT LOW FORMING ALONG THE MAINE COAST DURING SUNDAY.
AS THE PRIMARY LOW CONTINUES TO TRACK TO OUR NORTHWEST ON SUNDAY
WARMER AIR ALOFT WILL CONTINUE TO BRING MILDER AIR ALOFT WITH
PRECIPITATION CHANGE TO SLEET AND FREEZING RAIN ACROSS NORTHERN
AND CENTRAL AREAS AND EVEN ALL RAIN ACROSS DOWN EAST ESPECIALLY
THE COAST. RIGHT NOW IT APPEARS AS IF MOST AREAS WILL SEE SNOW
TOTAL RANGING FROM 3 TO 6 INCHES BEFORE THE CHANGEOVER OCCURS ON
SUNDAY. ICE ACCUMULATIONS ARE EXPECTED TO RANGE FROM ABOUT A
TENTH OF AN INCH CENTRAL AND DOWN EAST AND LESS THAN A TENTH OF AN
INCH ACROSS NORTHERN AREAS. SINCE THIS IS STILL A LATE FOURTH INTO
FIFTH PERIOD EVENT WONT BE ISSUING ANY HEADLINES YET BUT A THIS
TIME IT LOOKS LIKE WINTER WEATHER ADVISORIES WILL PROBABLY BE
NEEDED FOR JUST ABOUT ALL AREAS OF OUR CWA FOR SATURDAY NIGHT AND
SUNDAY FOR THE COMBINATION OF SNOW AND MIXED PRECIPITATION. THE
STEADY PRECIPITATION IS EXPECTED TO WIND DOWN ACROSS THE AREA AS
THE LOW CONTINUES TO TRACK TO THE NORTHEAST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
LOW PRESSURE WILL CONTINUE TO TRACK AWAY FROM THE REGION SUNDAY
NIGHT. ANY LINGERING SNOW SHOWERS OR MIXED PRECIPITATION WILL BE
DIMINISHING EARLY SUNDAY EVENING.
MUCH COLDER AIR WILL BEGIN TO POUR INTO THE REGION ON MONDAY WITH
HIGH TEMPERATURES OCCURRING EARLY IN THE DAY AND THEN FALLING IN
THE AFTERNOON. MONDAY NIGHT IS SHAPING UP AS A MAINLY CLEAR AND
BITTER COLD NIGHT WITH LOW FALLING TO 10 BELOW TO 15 BELOW ZERO
ACROSS THE NORTH AND ZERO TO 5 BELOW ZERO ACROSS CENTRAL AND DOWN
EAST. MAY NEED WIND CHILL ADVISORIES FOR NORTHERN AREAS AS WELL
AS WEST WINDS WILL MAKE IT FEEL EVEN COLDER.
TUESDAY WILL START OFF MAINLY CLEAR BEFORE CLOUDS BEGIN TO INCREASE
IN ADVANCE OF A CLIPPER TYPE SYSTEM APPROACHING FROM THE WEST.
EXPECT THE CHANCE FOR SNOW ESPECIALLY ACROSS DOWN EAST AREAS AS
THE SYSTEM MOVES EAST. THE SNOW MAY CONTINUE INTO THE FIRST PART
OF WEDNESDAY BEFORE DIMINISHING WEDNESDAY AFTERNOON.
EXPECT MAINLY DRY WEATHER WEDNESDAY NIGHT AND THURSDAY BUT
CONTINUED BELOW NORMAL TEMPERATURES.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: VFR CONDITIONS FOR THE MOST PART ACROSS THE REGION
W/TEMPO MVFR FOR THE NORTHERN TERMINALS TODAY W/SOME SNOW. WINDS
WILL PICK UP LATER THIS MORNING INTO THE AFTERNOON W/GUST
POTENTIAL ACROSS NORTHERN AREAS OF 25KTS.
SHORT TERM: VFR CONDITIONS EXPECTED ON SATURDAY. WIDESPREAD FLIGHT
RESTRICTIONS ARE EXPECTED TO DEVELOP SATURDAY NIGHT AND CONTINUE
ON SUNDAY WITH SNOW/SLEET/FREEZING RAIN EXPECTED TO AFFECT ALL
TERMINALS. R/WY SNOW ACCUMULATIONS FROM LATE SATURDAY NIGHT
THROUGH SUNDAY MAY RANGE FROM 3 TO 6 INCHES AT ALL THE TERMINALS
ALONG WITH THE POSSIBILITY OF SOME ICE ACCUMULATION ESPECIALLY
KBGR/KHUL TERMINALS. PRECIPITATION WILL BEGIN TO DIMINISH SUNDAY
EVENING WITH CONDITIONS IMPROVING TO VFR BY LATER SUNDAY NIGHT.
VFR CONDITIONS EXPECTED MONDAY. VFR MOST OF TUESDAY BUT POTENTIAL
FOR SNOW DEVELOPING LATE IN THE DAY ESPECIALLY KBGR/KBHB WITH
POSSIBLE IFR CONDITIONS BY TUE EVE.
&&
.MARINE...
NEAR TERM: A SMALL CRAFT ADVISORY REMAINS IN EFFECT THROUGH
TONIGHT W/GUSTS HITTING CLOSE TO 30 KTS. SEAS ARE RUNNING 7-10 FT
OVER THE OUTER ZONES AND THEY COULD BUILD A FEW MORE FT BEFORE
LEVELING OFF. SW WINDS WILL VEER TO THE WNW THIS AFTERNOON INTO
TONIGHT. ADJUSTMENTS WERE MADE TO THE SEAS TO ACCOUNT FOR THE
CURRENT CONDITIONS.
SHORT TERM: SMALL CRAFT ADVISORY CONDITIONS ARE POSSIBLE
SATURDAY. WINDS/SEAS WILL BRIEFLY DIMINISH EARLY SATURDAY EVENING
BEFORE INCREASING LATE SATURDAY NIGHT AND SUNDAY. A GALE WATCH
MAY BE REQUIRED FOR LATER SATURDAY NIGHT AND SUNDAY WITH CONTINUED
POTENTIAL FOR GALE FORCE WIND EARLY NEXT WEEK IN THE COLD
ADVECTION. VISIBILITY WILL BE UNRESRICTED SATURDAY AND THEN A
MILE OR LESS IN PRECIPITATION LATER SATURDAY NIGHT AND SUNDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR ANZ050>052.
&&
$$
NEAR TERM...HASTINGS/HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HASTINGS/HEWITT/DUDA
MARINE...HASTINGS/HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
634 AM EST FRI JAN 2 2015
.SYNOPSIS...
AN ARCTIC FRONT WILL SWEEP ACROSS THE REGION THIS AFTERNOON. HIGH
PRESSURE WILL BUILD INTO THE AREA TONIGHT THROUGH SATURDAY. LOW
PRESSURE TRACKING NORTHWEST OF MAINE WILL ALLOW A WARM FRONT TO
APPROACH THE REGION SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
630 AM UPDATE...ADJUSTED THE HRLY TEMPERATURES TO BRING THEM UP
FROM THE PREVIOUS THINKING COLDER IS JUST BEGINNING TO APCH
WESTERN MAINE ATTM W/THE ARCTIC FRONT. ANOTHER ADJUSTMENT WAS FOR
SNOW SHOWERS & SQUALLS A BIT FURTHER SOUTH THAN PREVIOUSLY
THOUGHT. MADE MANUAL ADJUSTMENTS TO THE POPS AND AREAL COVERAGE TO
ACCOUNT FOR ACTIVITY MAKING ITS WAY ACROSS CENTRAL AREAS. AN INCH
OF SNOW AT BEST IN THE HEAVIEST ACTIVITY THIS MORNING.
THE NAM AND LATEST HRRR 3KM WERE DOING QUITE WELL W/THE CURRENT
SETUP. THINKING HERE IS THAT THE FIRST BATCH OF SNOW SHOWERS
OCCURRING ATTM WILL MOVE ACROSS THE REGION W/THE BEST ENHANCEMENT
FROM MT. KATAHDIN TO THE SHERMAN-PATTEN REGION AS UP TO AN INCH OR
SNOW COULD ACCUMULATE. ANOTHER BATCH OF SNOW SHOWERS AND A FEW
SQUALLS LOOK LIKE THEY WILL SET UP BETWEEN 7 AM AND 10 AM THIS
MORNING W/THE ARCTIC FRONT APPROACHING. THE NAM SOUNDING SUPPORTS
850-700MBS LAPSE RATES AROUND 7.0 C/KM W/A FCST CAPE IN THE RANGE
OF 75-100 JOULES. THIS IS WHERE IS SOME AREAS COULD PICK UP
ANOTHER INCH OF SNOW W/SOME GUSTY WINDS. FURTHER SOUTH FROM THE
CENTRAL HIGHLANDS DOWN TO INTO TEH DOWNEAST REGION, MAINLY MOSTLY
CLOUDY W/A FEW FLURRIES. THINGS WIND DOWN NEAR OR AFTER 18Z.
TEMPERATURES LOOK LIKE THEY COULD ACTUALLY CLIMB SOME THIS MORNING
AHEAD OF THE FRONT AND THEN FALL BACK SHARPLY THIS AFTERNOON INTO
THE EVENING. ADJUSTMENTS WERE NEEDED TO THE MAXES TODAY TO BRING
THEM UP AND SHOW AN EARLY DAYTIME HIGH TEMP. CLOUDS SHOULD BREAK
UP THIS AFTERNOON AS THE LATEST IR SATELLITE IMAGERY SHOWS THAT
CLEARING BACK ACROSS QUEBEC AND THIS IS SUPPORTED BY THE NAM
GUIDANCE. WINDS WILL ALSO PICK UP FOR A TIME AS THE FRONT MOVES
IN.
THE CHALLENGE TONIGHT WILL BE HOW SOON THE REGION CLEARS OUT AND
HOW QUICKLY THE WINDS DROP OFF W/HIGH PRES MOVING RAPIDLY INTO
THE REGION OVERNIGHT. ANOTHER FACTOR WILL BE THE WNW FLOW COMING
OFF THE OPEN ST. LAWRENCE AS THIS AIRMASS IS QUITE COLD. SOUNDINGS
SHOW THE COLUMN TO DRY OUT THROUGH 500MBS W/THE EXCEPTION OF THE
CROWN OF MAINE AS SOME MOISTURE STAYS TRAPPED BETWEEN 925-850MBS.
DECIDED TO HANG ON TO SOME CLOUDS ACROSS THE CROWN AND WENT
W/CLEARING FOR THE REST OF THE CWA. SOMETIMES W/A SCENARIO LIKE
THIS ONE, LIGHT SNOW COULD SET UP, BUT SINCE THE AIRMASS LOOKS BE
DRY ABOVE 850MBS OVER THE CROWN, DECIDED TO STAY AWAY FROM ANY
MENTION OF LIGHT SNOW ATTM. STAYED CLOSE TO THE DAYCREW`S THINKING
OF OVERNIGHT LOWS DROPPING TO 10-15 BELOW ACROSS THE NORTH AND
CENTRAL AREAS W/SINGLE NUMBERS FOR THE DOWNEAST REGION INCLUDING
THE COAST. IF THE WINDS DROP OFF SOONER, THEN TEMPERATURES COULD
BE EVEN COLDER BY 7 AM SATURDAY. THIS CAN BE ASSESSED FURTHER BY
THE ONCOMING DAYCREW.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
SATURDAY IS SHAPING UP AS THE BETTER OF THE TWO WEEKEND DAYS AS
LONG AS YOU DONT MIND THE COLD. EXPECT PLENTY OF SUN TO START AS
HIGH PRESSURE MOVES ACROSS THE REGION. HIGH CLOUDS WILL BEGIN TO
INCREASE BY AFTERNOON. HIGH TEMPERATURES ON SATURDAY WILL ONLY
RANGE FROM THE SINGLE DIGITS TO AROUND 10 ABOVE NORTH AND CENTRAL
AREAS WITH MID TO UPPER TEENS DOWN EAST.
CLOUDS WILL CONTINUE TO INCREASE AND THICKEN SATURDAY EVENING IN
ADVANCE OF LOW PRESSURE APPROACHING FROM THE WEST. EXPECT
PRECIPITATION IN THE FORM OF SNOW TO DEVELOP FROM SOUTHWEST TO
NORTHEAST BY OR SHORTLY AFTER MIDNIGHT. WARMER AIR MOVING IN ALOFT
WILL RESULT IN THE PRECIPITATION MIXING WITH SLEET AND FREEZING
RAIN ACROSS DOWN EAST AREAS BY LATE SATURDAY NIGHT BUT THE
PRECIPITATION WILL REMAIN IN THE FORM OF ALL SNOW ACROSS NORTHERN
AND CENTRAL AREAS THROUGH THE NIGHT SATURDAY WITH SEVERAL INCHES
OF SNOW POSSIBLE BY DAYBREAK SUNDAY. LOW TEMPERATURES WILL OCCUR
EARLY IN THE EVENING SATURDAY BEFORE SLOWLY RISING OVERNIGHT.
PRECIPITATION WILL BE ONGOING FIRST THING SUNDAY AS LOW PRESSURE
CONTINUES TO TRACK TO OUR NORTHWEST. MODELS CONTINUE TO HINT AT A
WEAK TRIPLE POINT LOW FORMING ALONG THE MAINE COAST DURING SUNDAY.
AS THE PRIMARY LOW CONTINUES TO TRACK TO OUR NORTHWEST ON SUNDAY
WARMER AIR ALOFT WILL CONTINUE TO BRING MILDER AIR ALOFT WITH
PRECIPITATION CHANGE TO SLEET AND FREEZING RAIN ACROSS NORTHERN
AND CENTRAL AREAS AND EVEN ALL RAIN ACROSS DOWN EAST ESPECIALLY
THE COAST. RIGHT NOW IT APPEARS AS IF MOST AREAS WILL SEE SNOW
TOTAL RANGING FROM 3 TO 6 INCHES BEFORE THE CHANGEOVER OCCURS ON
SUNDAY. ICE ACCUMULATIONS ARE EXPECTED TO RANGE FROM ABOUT A
TENTH OF AN INCH CENTRAL AND DOWN EAST AND LESS THAN A TENTH OF AN
INCH ACROSS NORTHERN AREAS. SINCE THIS IS STILL A LATE FOURTH INTO
FIFTH PERIOD EVENT WONT BE ISSUING ANY HEADLINES YET BUT A THIS
TIME IT LOOKS LIKE WINTER WEATHER ADVISORIES WILL PROBABLY BE
NEEDED FOR JUST ABOUT ALL AREAS OF OUR CWA FOR SATURDAY NIGHT AND
SUNDAY FOR THE COMBINATION OF SNOW AND MIXED PRECIPITATION. THE
STEADY PRECIPITATION IS EXPECTED TO WIND DOWN ACROSS THE AREA AS
THE LOW CONTINUES TO TRACK TO THE NORTHEAST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
LOW PRESSURE WILL CONTINUE TO TRACK AWAY FROM THE REGION SUNDAY
NIGHT. ANY LINGERING SNOW SHOWERS OR MIXED PRECIPITATION WILL BE
DIMINISHING EARLY SUNDAY EVENING.
MUCH COLDER AIR WILL BEGIN TO POUR INTO THE REGION ON MONDAY WITH
HIGH TEMPERATURES OCCURRING EARLY IN THE DAY AND THEN FALLING IN
THE AFTERNOON. MONDAY NIGHT IS SHAPING UP AS A MAINLY CLEAR AND
BITTER COLD NIGHT WITH LOW FALLING TO 10 BELOW TO 15 BELOW ZERO
ACROSS THE NORTH AND ZERO TO 5 BELOW ZERO ACROSS CENTRAL AND DOWN
EAST. MAY NEED WIND CHILL ADVISORIES FOR NORTHERN AREAS AS WELL
AS WEST WINDS WILL MAKE IT FEEL EVEN COLDER.
TUESDAY WILL START OFF MAINLY CLEAR BEFORE CLOUDS BEGIN TO INCREASE
IN ADVANCE OF A CLIPPER TYPE SYSTEM APPROACHING FROM THE WEST.
EXPECT THE CHANCE FOR SNOW ESPECIALLY ACROSS DOWN EAST AREAS AS
THE SYSTEM MOVES EAST. THE SNOW MAY CONTINUE INTO THE FIRST PART
OF WEDNESDAY BEFORE DIMINISHING WEDNESDAY AFTERNOON.
EXPECT MAINLY DRY WEATHER WEDNESDAY NIGHT AND THURSDAY BUT
CONTINUED BELOW NORMAL TEMPERATURES.
&&
.AVIATION /11Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: VFR CONDITIONS FOR THE MOST PART ACROSS THE REGION
W/TEMPO MVFR FOR THE NORTHERN TERMINALS TODAY W/SOME SNOW. WINDS
WILL PICK UP LATER THIS MORNING INTO THE AFTERNOON W/GUST
POTENTIAL ACROSS NORTHERN AREAS OF 25KTS.
SHORT TERM: VFR CONDITIONS EXPECTED ON SATURDAY. WIDESPREAD FLIGHT
RESTRICTIONS ARE EXPECTED TO DEVELOP SATURDAY NIGHT AND CONTINUE
ON SUNDAY WITH SNOW/SLEET/FREEZING RAIN EXPECTED TO AFFECT ALL
TERMINALS. R/WY SNOW ACCUMULATIONS FROM LATE SATURDAY NIGHT
THROUGH SUNDAY MAY RANGE FROM 3 TO 6 INCHES AT ALL THE TERMINALS
ALONG WITH THE POSSIBILITY OF SOME ICE ACCUMULATION ESPECIALLY
KBGR/KHUL TERMINALS. PRECIPITATION WILL BEGIN TO DIMINISH SUNDAY
EVENING WITH CONDITIONS IMPROVING TO VFR BY LATER SUNDAY NIGHT.
VFR CONDITIONS EXPECTED MONDAY. VFR MOST OF TUESDAY BUT POTENTIAL
FOR SNOW DEVELOPING LATE IN THE DAY ESPECIALLY KBGR/KBHB WITH
POSSIBLE IFR CONDITIONS BY TUE EVE.
&&
.MARINE...
NEAR TERM: A SMALL CRAFT ADVISORY REMAINS IN EFFECT THROUGH
TONIGHT W/GUSTS HITTING CLOSE TO 30 KTS. SEAS ARE RUNNING 7-10 FT
OVER THE OUTER ZONES AND THEY COULD BUILD A FEW MORE FT BEFORE
LEVELING OFF. SW WINDS WILL VEER TO THE WNW THIS AFTERNOON INTO
TONIGHT. ADJUSTMENTS WERE MADE TO THE SEAS TO ACCOUNT FOR THE
CURRENT CONDITIONS.
SHORT TERM: SMALL CRAFT ADVISORY CONDITIONS ARE POSSIBLE
SATURDAY. WINDS/SEAS WILL BRIEFLY DIMINISH EARLY SATURDAY EVENING
BEFORE INCREASING LATE SATURDAY NIGHT AND SUNDAY. A GALE WATCH
MAY BE REQUIRED FOR LATER SATURDAY NIGHT AND SUNDAY WITH CONTINUED
POTENTIAL FOR GALE FORCE WIND EARLY NEXT WEEK IN THE COLD
ADVECTION. VISIBILITY WILL BE UNRESRICTED SATURDAY AND THEN A
MILE OR LESS IN PRECIPITATION LATER SATURDAY NIGHT AND SUNDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR ANZ050>052.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT/DUDA
MARINE...HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
104 AM EST FRI JAN 2 2015
.SYNOPSIS...
AN ARCTIC FRONT WILL SWEEP NORTHWEST TO SOUTHEAST THROUGH THE
REGION LATE OVERNIGHT INTO FRIDAY. HIGH PRESSURE WILL BUILD
ACROSS THE REGION FRIDAY NIGHT THROUGH SATURDAY. LOW PRESSURE
TRACKING NORTHWEST OF MAINE WILL ALLOW A WARM FRONT TO APPROACH
THE REGION SUNDAY.
&&
.NEAR TERM /THROUGH TODAY/...
1245 AM UPDATE: ADJUSTED THE POPS TO ALIGN BETTER W/THE LATEST
RADAR AND OBS SHOWING SOME SNOW MOVING ACROSS PORTIONS OF NORTHERN
MAINE. 05Z SURFACE ANALYSIS SHOWED PRE-FRONTAL TROF W/A LOW OVER
NW MAINE PUSHING E. TEH ARCTIC FRONT WAS STILL BACK INTO QUEBEC.
THIS PRE-FRONTAL TROF IS RESPONSIBLE FOR THE FIRST BURST OF SNOW,
MAINLY LIGHT. TEMPERATURES HOLDING IN THE UPPER TEENS AND LOW 20S
ACROSS THE NORTH AND WEST W/LOW TO MID 20S ELSEWHERE. THE MORE
SIGNIFICANT EVENT W/HEAVIER SNOW SHOWERS AND PERHAPS SOME SQUALLS
SET TO MOVE ACROSS NORTHERN AND WESTERN AREAS BETWEEN 3 AND 7 AM.
A QUICK INCH OF SNOW IS POSSIBLE W/SOME GUSTY WINDS. BTV SNOW
SQUALL PARAMETER SHOWS SOME ENHANCED SNOW SHOWERS/SQUALLS ACROSS
NORTHERN MAINE BETWEEN 4 AND 10 AM THIS MORNING. THE NAM12
SOUNDING INDICATED HEAVIEST ACTION BETWEEN 09-15Z AND WAS MATCHING
UP WELL PER 05Z OBS/RADAR.
THE TEMPERATURES WILL STAY UP FOR A TIME AS THE ARCTIC FRONT IS
SLOWER IN ARRIVING PER THE LATEST RAP AND NAM12 GUIDANCE.
TEMPERATURE WILL DROP OFF SHARPLY BEHIND THE FRONT AFTER 10 AM.
THE AFOREMENTIONED FRONT WILL FINISH ITS SOUTHWARD PUSH AND WILL
BE OFFSHORE BY LATER THIS AFTERNOON. AS SUCH, THE BULK OF THE
SNOW SHOWERS WILL COME TO AN END WITH JUST A FEW LINGERING SNOW
FLAKES POSSIBLE OVER NORTHERN MAINE. HIGHS WILL BE CHILLY IN THE
NORTH...10 TO 15 DEGREES...BUT CENTRAL AND SOUTHERN MAINE WILL BE
A BIT BETTER, TOPPING OUT IN THE 20S TO AROUND 30.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...
COULD HAVE A SLIGHT CHANCE OF SNOW SHOWERS ACROSS THE
NORTH/MOUNTAINS EARLY FRIDAY NIGHT. OTHERWISE...HIGH PRESSURE
BUILDS EAST TOWARD THE REGION FRIDAY NIGHT WITH DECREASING CLOUDS
NORTH AND MOSTLY CLEAR SKIES DOWNEAST. HIGH PRESSURE THEN CROSSES
THE REGION SATURDAY WITH PARTLY/MOSTLY SUNNY SKIES. LOW PRESSURE
LIFTING ACROSS THE GREAT LAKES WILL DRAW A WARM FRONT TOWARD NEW
ENGLAND SATURDAY NIGHT. CLOUD COVER WILL INCREASE ACROSS THE
REGION EARLY SATURDAY NIGHT. LOW TEMPERATURES SATURDAY NIGHT WILL
OCCUR EARLY THEN BEGIN TO RISE OVERNIGHT WITH THE INCREASING
CLOUDS. OVERRUNNING PRECIPITATION WILL THEN EXPAND ACROSS THE
FORECAST AREA LATER SATURDAY NIGHT. BASED ON CRITICAL
THICKNESSES...EXPECT PRECIPITATION TO REMAIN MOSTLY IN THE FORM OF
SNOW ACROSS THE FORECAST AREA SATURDAY NIGHT. HOWEVER...THE SNOW
COULD BEGIN TO TRANSITION TO A WINTRY MIX ACROSS DOWNEAST AREAS
LATE. THE PRIMARY GREAT LAKES LOW TRACKS NORTHWEST OF THE REGION
SUNDAY DRAWING THE WARM FRONT NORTH ACROSS THE REGION. MODELS
INDICATE THE POSSIBILITY THAT A WEAK SECONDARY LOW COULD DEVELOP
ALONG THE WARM FRONT AND MOVE ALONG THE COAST...THOUGH THE EXTENT
TO WHICH THE LOW DEVELOPS IS UNCERTAIN. EXPECT A WINTRY MIX TO
TRANSITION TO MOSTLY RAIN ACROSS MUCH OF THE DOWNEAST AREA SUNDAY
AFTERNOON...WITH SNOW TRANSITIONING TO A WINTRY MIX ACROSS
NORTHERN AREAS. PRECIPITATION TYPES WILL BE DEPENDENT ON HOW
QUICKLY THE LOW LEVEL COLD AIR CAN BE ERODED. A STRONGER SECONDARY
LOW MOVING ALONG THE COAST WOULD HELP THE LOW LEVEL COLD AIR
REMAIN MORE PERSISTENT ACROSS INTERIOR DOWNEAST AREAS...WHILE A
WEAKER LOW WOULD ALLOW THE LOW LEVEL COLD AIR TO BE ERODED MORE
RAPIDLY. GENERALLY EXPECT STORM TOTAL SNOW ACCUMULATION OF 4 TO 7
INCHES ACROSS NORTHERN AREAS THROUGH SUNDAY WITH 3 TO 5 INCHES
DOWNEAST. SLEET AND ICE ACCUMULATIONS WILL BE DEPENDENT ON THE
TIMING OF THE TRANSITION FROM SNOW WHICH IS STILL UNCERTAIN AT
THIS TIME. TEMPERATURES WILL BE AT BELOW NORMAL LEVELS
SATURDAY...THEN AT ABOVE NORMAL LEVELS SUNDAY DEPENDENT ON THE
EXTENT OF LOW LEVEL WARMING.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
LATEST RUN OF GFS/ECMWF IN GOOD AGREEMENT TRACKING LOW PRESSURE
NORTH OF CWA THROUGH MONDAY WITH STRONG NORTHWEST TO NORTH
GRADIENT ESTABLISHING FOR GUSTY WINDS AND A RAPID DECREASE IN
TEMPERATURES. SNOW SHOWER ACTIVITY...OR MIXED PRECIPITATION ALONG
DOWNEAST...WILL DIMINISH QUICKLY ACROSS THE AREA BY MONDAY NIGHT.
ANOTHER LOW APPROACHES FROM THE GREAT LAKES ON TUESDAY BUT CURRENT
GUIDANCE KEEPS THE SYSTEM OFFSHORE RESULTING IN CHANCE POPS ALONG
DOWNEAST COAST AND SLIGHT CHANCE TO CENTRAL AREAS THROUGH EARLY
THURSDAY. HIGH PRESSURE THEN BUILDS IN FROM THE WEST ON THURSDAY
FOR A BRIEF RESPITE BEFORE A CLIPPER SYSTEM APPROACHES AGAIN FROM
THE WEST. TEMPERATURES THROUGH THE WEEK WILL REMAIN WELL BELOW
NORMALS.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: VFR CONDITIONS WILL PREVAIL AT THE SOUTHERN TERMINALS
THROUGH THE PERIOD. HOWEVER, AT KCAR/KFVE/KPQI, A COLD FRONTAL
PASSAGE WILL BRING SNOW SHOWERS AND PERHAPS EVEN SNOW SQUALLS.
PREVAILING MVFR CONDITIONS ARE EXPECTED 22Z THU THRU 12Z FRIDAY,
WITH IFR/LIFR POSSIBLE IN ANY SNOW. CONDITIONS WILL IMPROVE
THROUGH THE DAY FRIDAY WITH LIFTING CEILINGS AND DECREASING
COVERAGE OF SNOW SHOWERS.
SHORT TERM: COULD HAVE LOCALIZED MVFR CONDITIONS ACROSS THE
NORTH AND MOUNTAINS EARLY FRIDAY NIGHT. OTHERWISE...VFR
CONDITIONS ARE EXPECTED ACROSS THE REGION FRIDAY NIGHT INTO EARLY
SATURDAY NIGHT. CONDITIONS WILL LOWER TO IFR/LIFR LEVELS LATER
SATURDAY NIGHT WITH SIMILAR CONDITIONS PERSISTING INTO EARLY
SUNDAY NIGHT. CONDITIONS WILL IMPROVE TO MVFR/VFR LEVELS ACROSS
NORTHERN AREAS LATER SUNDAY NIGHT...WITH VFR CONDITIONS DEVELOPING
DOWNEAST. OCCASIONAL MVFR CONDITIONS COULD PERSIST ACROSS THE
NORTH AND MOUNTAINS MONDAY. OTHERWISE...VFR CONDITIONS ARE
EXPECTED ACROSS THE REGION MONDAY INTO TUESDAY.
&&
.MARINE...
NEAR TERM: A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR TONIGHT,
BUT IT HAS BEEN EXTENDED THROUGH FRIDAY. WINDS WILL INCREASE AHEAD
OF AN APPROACHING COLD FRONT TONIGHT, AND THEN SWITCH TO THE
WEST/NORTHWEST FRIDAY AS THE FRONT CROSSES THE GULF OF MAINE.
WINDS OF 10 TO 20 KT WITH GUSTS UP TO 30 KT ARE EXPECTED THROUGH
THE PERIOD.
SHORT TERM: SMALL CRAFT ADVISORY CONDITIONS WILL OCCUR FRIDAY
NIGHT INTO EARLY SATURDAY. CONDITIONS WILL BRIEFLY FALL BELOW
SMALL CRAFT ADVISORY LEVELS SATURDAY AFTERNOON INTO EARLY
SATURDAY NIGHT. SMALL CRAFT ADVISORY CONDITIONS WILL DEVELOP AGAIN
LATER SATURDAY NIGHT. STRONG SMALL CRAFT ADVISORY...OR POSSIBLY
GALE CONDITIONS...WILL OCCUR SUNDAY. VISIBILITIES WILL LOWER IN
DEVELOPING SNOW AND MIXED PRECIPITATION LATER SATURDAY
NIGHT...WITH MIXED PRECIPITATION CHANGING TO RAIN SUNDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR ANZ050>052.
&&
$$
NEAR TERM...HEWITT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
701 PM EST SAT JAN 3 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 335 PM EST SAT JAN 3 2015
UPPER MICHIGAN IS CURRENTLY BETWEEN THE STRONGER AND PRECIPITATION
PRODUCING SURFACE/UPPER LEVEL FEATURES. THE REMNANTS OF THE SURFACE
LOW THAT MOVED THROUGH MINNESOTA LAST NIGHT HAS LEFT A SURFACE
TROUGH OVER WESTERN LAKE SUPERIOR THIS AFTERNOON. ON THE NORTHWEST
SIDE OF THAT TROUGH...SNOW HAS BEEN FALLING FOR MUCH OF THE DAY IN
THE MINNESOTA ARROWHEAD IN ASSOCIATION WITH THE MID LEVEL Q-VECTOR
CONVERGENCE AND THE RIGHT REAR OF THE SPLIT NORTHERN STREAM JET
STREAK. FARTHER SOUTH...WATER VAPOR IMAGERY SHOWS A STRONG UPPER
WAVE LIFTING NORTHEAST OUT OF THE SOUTHERN PLAINS...WHILE A SECOND
WEAKER WAVE IS NEARING IT FROM THE NORTHWEST IN COLORADO. BETWEEN
THESE TWO FEATURES AND BEHIND THE SHORTWAVE THAT MOVED THROUGH
SOUTHEAST UPPER MICHIGAN LAST NIGHT AND THIS MORNING (PRODUCING
1-1.5IN OF SNOW NEAR LAKE MICHIGAN)...CLOUDY SKIES PREVAIL OVER
UPPER MICHIGAN. THIS IS DUE TO THE LINGERING LOW LEVEL MOISTURE
TRAPPED BELOW THE DRYING ALOFT BEHIND THE SHORTWAVE. ONCE THE DEEPER
MOISTURE DEPARTED WITH THE SHORTWAVE...SAW A TRANSITION TO BR AND
REDUCED VISIBILITIES ON THE AUTOMATED STATIONS. CALLING AROUND TO
THE SOUTHERN PART OF THE CWA HAS SHOWN A TRANSITION FROM WEST TO
EAST ALONG THE WISCONSIN BORDER TO FREEZING DRIZZLE OVER THE LAST
COUPLE OF HOURS. FARTHER NORTH AT OUR OFFICE...WE HAVE BEEN JUST
SEEING A FEW FLURRIES DUE TO CLOUD LAYER BEING RIGHT AT THE EDGE OF
THE MORE FAVORABLE ICE CRYSTAL REGION. EXPECT THIS
BORDERLINE/LIMITED CONDITION TO CONTINUE OVER THE SOUTH CENTRAL AND
SOUTHEASTERN CWA INTO THE EVENING HOURS AND WILL SHOW THE POTENTIAL
FOR FREEZING DRIZZLE IN THE FORECAST. WILL ISSUE AN SPS TO
HIGHLIGHT THE FREEZING DRIZZLE AND UNTREATED ROADS BECOMING
SLIPPERY FOR THE AREAS NOT CURRENTLY COVERED BY THE ADVISORY.
OTHERWISE...EXPECT THE FREEZING DRIZZLE TO DIMINISH FROM WEST TO
EAST THIS EVENING AS THE DEEPER MOISTURE FROM THE FEATURE OVER
WESTERN LAKE SUPERIOR MOVES OVER THE U.P. TONIGHT.
THE STRONG TROUGH IN THE SOUTHERN PLAINS WILL LIFT NORTHEAST
THROUGH THE LOWER GREAT LAKES REGION TONIGHT...STRENGTHENING A LOW
FROM 1007MB OVER SOUTHERN ILLINOIS TO 998MB BETWEEN LAKE
ERIE/ONTARIO AT 12Z SUNDAY. AS THAT OCCURS...THE MID LEVEL TROUGH
ASSOCIATED WITH THE SURFACE TROUGH OVER THE WESTERN LAKE WILL
DROP SOUTHEAST ACROSS UPPER MICHIGAN THROUGH SUNDAY MORNING. THE
SYNOPTIC LIQUID EQUIVALENT PRECIPITATION (TIED TO THE 850-650MB
FGEN) LOOKS TO BE IN THE 0.10-0.15 INCH RANGE FOR MOST OF THE CWA
THROUGH SUNDAY MORNING. SNOW RATIOS INITIALLY WILL LIKELY BE AROUND
10-15 TO 1 AS THERE IS STILL A PERIOD OF THE CLOUD BEING ABOVE/BELOW
THE DGZ. BUT THERE WILL LIKELY BE A TRANSITION TO A BRIEF (2-4HR)
PERIOD LATE TONIGHT INTO SUNDAY MORNING WHEN THE LOWEST 10-12KFT OF
THE ATMOSPHERE IS WITHIN THE DGZ. THIS WOULD LEAD TO A PERIOD OF
FLUFFIER SNOW AND RATIOS RISING TOWARDS OR EVEN ABOVE 20-1. DON/T
FEEL COMFORTABLE GOING MUCH ABOVE THAT DUE TO THE FORCING THAT IS
EXPECTED ABOVE THE DGZ. THUS...SYNOPTIC SNOW WOULD AMOUNT TO
1 TO 2.5-3.0 INCHES...WITH THE GREATEST OVER THE WEST HALF. BUT AS
IS NORMALLY THE CASE WITH LAKE SUPERIOR AND OUR TERRAIN
INFLUENCES...THAT ISN/T THE COMPLETE STORY ON THE SNOWFALL.
MUCH COLDER AIR WILL SURGE INTO THE AREA TONIGHT BEHIND THE
850-700MB TROUGH...WITH 850MB TEMPS FALLING FROM 19Z RAP ANALYZED
OF -5C TO -7C TO -19C EAST AND -24C WEST BY 18Z SUNDAY. THIS WILL
LEAD TO LAKE ENHANCEMENT DEVELOPING FROM WEST TO EAST TONIGHT AND
THEN TRANSITIONING TO PURE LAKE EFFECT AS THE DEEPER MOISTURE
DEPARTS ON SUNDAY. THE HELP FROM THE LAKE WILL BE FOCUSED IN THE
NORTHERLY WIND LOCATIONS OF THE WEST AND NORTH CENTRAL TONIGHT AND
THEN WINDS BACK TO THE NORTHWEST SUNDAY MORNING AND WEST-NORTHWEST
BY SUNDAY EVENING. WITH THAT COLD AIR SURGING IN...THE CLOUD LAYER
ON SUNDAY WILL TRANSITION TO BEING ABOVE THE DGZ. THUS...WOULD
EXPECT A TRANSITION OF THE SNOWFLAKES TO COLUMNS/PLATES AND LOWER
SNOW RATIOS BELOW 20-1. CONTINUED THE TREND TOWARDS THE HIGH
RESOLUTION MODELS FOR QPF AMOUNTS TONIGHT/SUNDAY IN THE
LAKE/TERRAIN ENHANCED AREAS (0.25-0.40 IN). THIS LEADS TO SNOWFALL
AMOUNTS OF 3-5 INCHES OF SNOW TONIGHT OVER THE FAVORED NORTH WIND
AREAS OVER THE WEST AND NORTH CENTRAL. THERE COULD BE SOME
LOCALIZED HIGHER AMOUNTS TOWARDS 5.5-6.0 INCHES. THE LOWERING RATIOS
ON SUNDAY WILL LEAD TO LOWER AMOUNTS OVER THE WEST...BUT COULD
STILL SEE 2-5 INCHES IN THE FAVORED NORTHWEST WINDS AREAS OVER THE
EAST. IN ADDITION TO THE SNOW...WINDS WILL QUICKLY INCREASE FROM
NORTHWEST TO SOUTHEAST TONIGHT...WITH GUSTS BETWEEN 30 TO 45 MPH
(HIGHEST NEAR LAKE SUPERIOR). THAT WILL LEAD TO BLOWING SNOW AND
COMBINED WITH THE EXPECTED SNOW...SHOULD SEE VISIBILITIES
FREQUENTLY REDUCED BELOW ONE MILE OVER THE NORTHERN HALF OF THE
CWA. THUS...THINK THE GOING ADVISORY LOOKS GOOD WITH THE FORECASTED
SNOWFALL AMOUNTS AND IMPACT WITH THE REDUCED VISIBILITIES FROM
BLOWING SNOW. AS MENTIONED ABOVE...THINK SOME HIGHER TERRAIN
LOCATIONS FLIRTING WITH 12HR WARNING SNOWFALL AMOUNTS (DUE TO THE
OVERALL AVERAGE SNOW RATIO BEING JUST BELOW OUR LAKE EFFECT WARNING
CRITERIA). BUT WITH MUCH OF THE SNOW FALLING ON A WEEKEND
OVERNIGHT AND THE EXPECTED COVERAGE FAIRLY LOCALIZED...WILL KEEP
THE ADVISORY IN PLACE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 426 PM EST SAT JAN 3 2015
TROUGHING AND WELL BELOW NORMAL TEMPERATURES DOMINATES THE WEATHER
PATTERN FOR THE FIRST FULL WEEK OF 2015 OVER NORTH AMERICA. STILL
INDICTIONS THAT A TRANSITION TO ZONAL FLOW AND ABOVE NORMAL TEMPS
DEVELOPS BY MID MONTH. ECMWF INDICATES THIS PATTERN SWITCH MAY OCCUR
AS EARLY AS NEXT WEEKEND WHILE GFS IS A BIT SLOWER. WOULD TEND TO
THINK IT MAY TAKE LONGER GIVEN THE DEGREE OF COLD AIR OVER THE
REGION AS LATE AS FRIDAY. EITHER WAY THIS UPCOMING WEEK WILL BE A
VERY COLD ONE WITH SUBZERO HIGHS ON SOME DAYS AND DANGEROUSLY LOW
WIND CHILLS. PATTERN DOES NOT HOLD MUCH OPPORTUNITY FOR WIDESPREAD
SNOW...BUT MAINLY LAKE EFFECT SNOW FOR AREAS NEAR LK SUPERIOR
FAVORED BY NORTHWEST OR WEST WINDS.
LES IN NW FLOW AREAS NEAR LAKE SUPERIOR WILL BE ONGOING SUNDAY NIGHT
IN WAKE OF THE LOW PRESSURE SYSTEM MOVING OVER THE CNTRL GREAT LAKES
ON SUNDAY. THOUGH MAIN SHORTWAVE AND SFC TROUGH WILL BE EAST OF THE
AREA...MULTIPLE SMALLER SHORTWAVES MAY PROVIDE SLIGHT ENHANCEMENT TO
LES. OVER-WATER INSTABILITY EASILY EXTREME WITH H85 TEMPS DOWN TO
-26C TO -28C AND 950MB TEMPS -22C TO -27C. LK SUPERIOR TEMPS STILL
+2C TO 3C. INVERSION HEIGHTS TOP OUT AT THE END OF THE FETCH OVER
EASTERN LK SUPERIOR 6-7KFT. DUE TO SUCH COLD AIR THE SLR/S WILL BE
WELL BLO 20:1 AS SNOWFLAKES WITHIN CONVECTIVE LAYER WILL BE PLATES
AND COLUMNS INSTEAD OF DENDRITES. RESULT IS A SNOW THAT WILL NOT
ADD UP MUCH IN TERMS OF ACCUMULATIONS...BUT WILL BE GOOD AT REDUCING
VISIBILITY. BASED ON 925MB WINDS...STEADIER LES EXPECTED SUNDAY
NIGHT AND MONDAY OVER THE KEWEENAW PENINSULA AND FOR THE SNOW BELTS
EAST OF MARQUETTE. POSSIBLE THAT ADDITIONAL ADVISORIES OR EXTENSION
OF CURRENT WINTER WEATHER ADVISORIES FOR LES WITH LOW VSBY AND GUSTY
WINDS MAY BE NEEDED INTO MONDAY...BUT WILL LET LATER SHIFTS EVALUATE
THIS ONCE WE GET THROUGH THE CURRENT ADVISORIES POSTED INTO SUNDAY.
OTHER THAN THE LES...THE COLD AND DANGEROUS WIND CHILLS WILL BE THE
MAIN STORY OVER THE CWA TO START THE WEEK. SFC RIDGE AXIS OVER THE
NORTHERN TO CENTRAL PLAINS AND LAKE INDUCED TROUGH WILL LEAD TO
MODEST PRESSURE GRADIENT OVER UPR MICHIGAN SUNDAY NIGHT INTO MONDAY
MORNING...BUT THERE IS NOT MUCH OF A LOW-LEVEL WIND MAX OVERHEAD AT
THAT TIME. EVEN SO...IT WILL NOT TAKE MUCH WIND TO PRODUCE NEAR
WARNING WIND CHILLS AS SFC TEMPS ARE EXPECTED TO BE -15F OR EVEN
-20F OVER FAR SW UPR MICHIGAN. STRONGER WINDS OF 10-15 MPH MAY BE
CLOSER TO LAKE INDUCED TROUGHING ALONG SOUTH SHORE OF LK SUPERIOR
WHERE TEMPS SHOULD BE MORE IN THE SINGLE DIGITS BLO ZERO. WIND CHILL
ADVISORIES WILL BE NEEDED FOR WEST HALF OF UPR MICHIGAN SUNDAY NIGHT
AND MONDAY...WITH POSSIBLE WARNINGS OVER FAR SW UPR MICHIGAN. COORD
WITH DLH AND GRB AND ISSUED A WIND CHILL WATCH FOR AREAS OF SW UPR
MICHIGAN /GOGEBIC...IRON...DICKINSON/ WHERE WARNING CRITERIA OF -35F
HAS BEST CHANCE OF OCCURRING.
LATER IN THE DAY ON MONDAY...A CLIPPER SHORTWAVE DIVING SE OUT OF
BRITISH COLUMBIA AND ALBERTA WILL SPREAD SNOW OVER THE NORTHERN
PLAINS AND EVENTUALLY THIS SNOW WILL MAKE IT TO THE WESTERN GREAT
LAKES ON MONDAY NIGHT. ATTM IT APPEARS THAT BULK OF THIS SYSTEM WILL
MISS UPR MICHIGAN. BY MONDAY AFTN AND MONDAY EVENING THOUGH...WINDS
BACKING WSW-SW AHEAD OF MORE NORTHERN STREAM SHORTWAVE AND COLD
FRONT DIVING SOUTHWARD OVER MANITOBA SHOULD PUSH THE LES OVER FAR
NORTHERN KEWEENAW AND OFFSHORE FM THE SNOW BELTS EAST OF MARQUETTE.
DOES NOT APPEAR WINDS BACK ENOUGH ON LK MICHIGAN TO BRING LES OFF LK
MICHIGAN INTO PLAY FOR SE CWA. LES STAYS MAINLY IN THE W FLOW AREAS
ON MONDAY NIGHT...BUT AS THE SHORTWAVE/COLD FRONT ARRIVE ON TUESDAY
WILL PUSH BACK TO NW FLOW AREAS NEAR LK SUPERIOR. SOUNDINGS SHOW
SHORTWAVE AND FRONT HAS MORE OF AN AFFECT ON THE LES AS INVERSIONS
RISE UP TO 10 KFT AS MORE COLD AIR WITH H85 TEMPS DOWN BLO -26C
SLIDES OVER THE UPPER GREAT LAKES. LIKE MONDAY...ALL OF CONVECTIVE
DEPTH IS AT TEMPS LOWER THAN DGZ...SO SMALL FLAKE SIZE AND LOW SLR/S.
NW WINDS IN MIXED LAYER NEAR 30 KTS...SO BLSN MORE OF AN ISSUE THAN
MONDAY. OVERALL THE POOR VSBY WILL CONINUE TO BE MAIN HAZARD FM THE
LES. AIR TEMPS MAY NOT BE QUITE AS COLD AS MONDAY MORNING BUT COLD
FRONT AND PRESSURE GRADIENT LOOKS MORE ROBUST. LIKELY LOOKING AT
ANOTHER ROUND OF WIND CHILL ADVISORIES FOR WEST HALF OF CWA LATE
TUESDAY NIGHT INTO WEDNESDAY MORNING. PROBABLY SHOULD STAY AWAY FM
ANY WARNING CRITERIA THOUGH.
COLD FRONT MOVES ON THROUGH WEDNESDAY AND 1045-1050MB HIGH PRESSURE
RIDGE OVER NORTHERN PLAINS PUSHES TO SOUTHERN PLAINS AND OHIO
VALLEY. IN RESPONSE...BLYR WINDS BACK MORE WNW-W BY WEDNESDAY
EVENING SO THE LES WILL IN TURN SHIFT AROUND AND NOT STAY PUT IN ANY
ONE PLACE TOO LONG. BEST CHANCE FOR MODERATE ACCUMS AND PERSISTENT
LOW VSBY WILL BE AT THE END OF THE FETCH IN THE SNOW BELTS TO EAST
OF MARQUETTE. ANOTHER COLD FRONT WILL DROP ACROSS UPPER LAKES ON
THURSDAY. YET ANOTHER SURGE OF H85 TEMPS BLO -25C WILL DESCEND ON
THE AREA. AHEAD OF THE COLD FRONT FOR THURSDAY...WEST WINDS MAY BE
STIFF LATE WEDNESDAY NIGHT INTO THURSDAY MORNING. THE STRONGER WINDS
ALONG WITH TEMPS LESS THAN 10 BLO WILL PROBABLY RESULT IN MORE WIND
CHILL ADVISORIES FOR MOST OF THE WEST HALF ON THURSDAY MORNING.
PROBABLY ARE GETTING THE THEME BY NOW. THIS WEEK LOOKS QUITE BRUTAL
IN TERMS OF THE PROLONGED DURATION OF BITTER COLD AND WIND CHILL
ISSUES. THIS WILL MAKE THE THAW EXPECTED FOR MID JANUARY FEEL ALL
THE MORE BETTER.
NW FLOW LES TO CLOSE THE WEEK AND INTO NEXT SATURDAY. THE NW WINDS
WILL RESULT IN MORE LAKE MODERATION SO TEMPS WILL BE PROBABLY BE
WARM ENOUGH TO LIMIT THE NEED OF ANY MORE WIND CHILL HEADLINES ON
FRIDAY MORNING OR SATURDAY MORNING. COULD SEE SWATH OF LGT SNOW
SWEEP OVER THE REGION NEXT WEEKEND AS THE WARM AIR BEGINS TO PUSH
OVER THE REGION ATOP OF SLOWLY RETREATING COLD AIR NEAR SFC.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 701 PM EST SAT JAN 3 2015
COLD FRONT IS CURRENTLY MOVING ACROSS WRN LAKE SUPERIOR AND WILL
REACH KIWD/KCMX IN THE NEXT FEW HRS. THIS WILL RESULT IN
DETERIORATING CONDITIONS AT KIWD/KCMX THIS EVENING AS SNOW AND WINDS
INCREASE. EXPECT MVFR CONDITIONS AT BOTH TERMINALS TO FALL TO LIFR
THIS EVENING WITH LIFR CONDITIONS THEN CONTINUING THRU THE NIGHT.
CONDITIONS AT KIWD WILL IMPROVE TO IFR LATE SUN MORNING AND TO MVFR
LATE IN THE AFTN AS WINDS BACK SLOWLY AND PUSH MAJORITY OF LAKE
EFFECT SNOW TO JUST N OF THE TERMINAL. AT KCMX...INCREASINGLY COLDER
AIR THRU THE DAY WILL RESULT IN SNOWFLAKES BECOMING SMALLER AND
FINER AND MUCH MORE EFFECTIVE AT REDUCING VIS. COMBINED WITH GUSTY
WINDS/BLSN...KCMX WILL LIKELY REMAIN LIFR THRU THE MORNING WITH
FURTHER REDUCTION TO VLIFR LIKELY IN THE AFTN AS WINDS BACK TO A
MORE FAVORABLE WNW DIRECTION FOR PERSISTENT/HEAVIER SNOW SHOWERS. AT
KSAW...IFR CONDITIONS ARE LIKELY TO CONTINUE THIS EVENING WITH
REDUCTION TO LIFR OVERNIGHT AS AREA OF SNOW MOVES ACROSS THE AREA
AND IS ENHANCED BY INCREASING UPSLOPE WIND OFF THE LAKE. EXPECT
IMPROVEMENT TO IFR MID TO LATE MORNING AND THEN MVFR IN THE AFTN AS
WINDS BACK...RESULTING IN DIMINISHED UPSLOPE FLOW OFF THE LAKE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 335 PM EST SAT JAN 3 2015
THE BUSY MARINE WEATHER WE HAVE HAD RECENTLY WILL CONTINUE WITH
GALES AND HEAVY FREEZING SPRAY RETURNING AND HOISTED GALE WARNINGS
AND HEAVY FREEZING SPRAY WARNINGS FOR LATE TONIGHT INTO SUNDAY. A
COUPLE MORE GALE EVENTS ARE POSSIBLE ON LAKE SUPERIOR TUESDAY NIGHT
AND WEDNESDAY MORNING AND AGAIN FOR THURSDAY NIGHT WITH NORTHWEST
GALES EXPECTED THEN. FREEZING SPRAY WILL ALSO BE A PROBLEM THROUGH
MOST OF THIS FORECAST PERIOD.
WINDS SHIFT TO THE NORTH LATE TONIGHT AS THE NORTHERN PLAINS
TROUGH MERGES WITH ANOTHER LOW PRESSURE SYSTEM LIFTING NORTH OVER
THE CENTRAL GREAT LAKES. NORTH GALES TO 35-40 KTS ARE EXPECTED
SUNDAY ESPECIALLY OVER THE EASTERN HALF OF LK SUPERIOR. HEAVY
FREEZING SPRAY WILL DEVELOP TONIGHT AS ARCTIC AIR POURS OVER
LK SUPERIOR. GALES SHOULD DIMINISH BY LATE SUNDAY NIGHT...BUT NW-W
WINDS TO 30 KTS AND HEAVY FREEZING SPRAY WILL LINGER THROUGH MONDAY.
W-SW WINDS TO 25 KTS ON TUESDAY AS A CLIPPER SYSTEM CROSSES UPPER
GREAT LAKES. BEHIND THE CLIPPER...PLAN ON ANOTHER ROUND OF NW GALES
AND HEAVY FREEZING SPRAY THROUGH WEDNESDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 7 PM EST /6 PM CST/ SUNDAY FOR
MIZ001>003-009-084.
WINTER WEATHER ADVISORY FROM 4 AM TO 7 PM EST SUNDAY FOR MIZ006-
007-085.
LAKESHORE FLOOD ADVISORY FROM 1 AM TO 1 PM EST SUNDAY FOR
MIZ001>003.
WIND CHILL WATCH FROM SUNDAY EVENING THROUGH MONDAY MORNING FOR
MIZ009>011.
LAKESHORE FLOOD ADVISORY FROM 7 AM TO 7 PM EST SUNDAY FOR
MIZ005>007.
WINTER WEATHER ADVISORY FROM 1 AM TO 7 PM EST SUNDAY FOR MIZ004-
005.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 1 AM EST FRIDAY
FOR LSZ251-267.
GALE WARNING FROM 4 AM SUNDAY TO 7 AM EST MONDAY FOR LSZ249>251-
267.
HEAVY FREEZING SPRAY WARNING FROM 1 AM SUNDAY TO 1 AM EST FRIDAY
FOR LSZ249-250-266.
GALE WARNING FROM 1 AM SUNDAY TO 7 AM EST MONDAY FOR LSZ266.
HEAVY FREEZING SPRAY WARNING UNTIL 1 AM EST /MIDNIGHT CST/
FRIDAY FOR LSZ162-240>248-263>265.
GALE WARNING UNTIL 7 AM EST /6 AM CST/ MONDAY FOR LSZ240>248-
263>265.
LAKE MICHIGAN...
GALE WARNING FROM 7 AM TO 7 PM EST SUNDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...SRF
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
508 AM EST FRI JAN 2 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 351 PM EST THU JAN 1 2015
DEEP TROUGH ALOFT CENTERED OVER HUDSON BAY. MULTIPLE SHORTWAVES
MOVING THROUGH THE BASE OF THE TROUGH...BUT AFTER THE SHORTWAVE
MOVED THROUGH THIS MORNING...THERE IS NO LARGER SCALE SUPPORT OVER
THE AREA OR UPSTREAM. PRIMARY COLD FRONT TIED TO THE LAST SHORTWAVE
IS CURRENTLY SINKING SOUTHWARD OVER UPR MICHIGAN. BAND OF HEAVY SNOW
ALONG THE FRONT HAS WORKED THROUGH MARQUETTE AND MUNISING AND IS NOW
ALLIGNED FM SAWYER TO CHATHAM TO SHINGLETON AND TO NEWBERRY AS OF 20Z.
VSBY DOWN TO 1/4SM IN THIS SNOW BAND...BUT IT IS NOT LASTING TOO LONG.
LES OVER THE WESTERN CWA IS SCUFFLING ALONG. IN FACT AFTER THE FRONT
MOVED THROUGH THE KEWEENAW...SPOTS HAVE CLEARED OUT BRIEFLY. HINTS OF
WIND PARALLEL BANDS OVER WESTERN LK SUPERIOR...BUT DRY AIR AND
INVERSIONS BLO 5KFT IS LIMITING THIS DEVELOPMENT. BETTER LES
DEVELOPMENT OVER EASTERN LK SUPERIOR WITH CLOUD STREETS EXTENDING
BACK TO NCNTRL LK SUPERIOR. WILL TAKE A FEW HOURS...BUT DO EXPECT AT
LEAST MODERATE LES TO DEVELOP IN THE NW LOW-LEVEL WINDS INTO EASTERN
CWA. BLYR WINDS OVER 30 KTS INTO THE EVENING WILL RESULT IN BLSN/POOR
VSBY IN THE HEAVIER SNOW BANDS. INVERSIONS 5-8 KFT AND TEMPS AT
INVERSION TOP OF -20C SHOULD AT LEAST RESULT IN SCT HEAVIER SNOW
SHOWERS. 17Z HRRR DOING NICE JOB WITH EXPECTED EVOLUTION THROUGH THE
EVENING...THOUGH IT SEEMS A BIT SLOW WITH TIMING OF HEAVIER SNOW BAND
TIED TO THE FRONT.
ADDITIONAL SNOW AMOUNTS SHOULD STAY IN CHECK GIVEN LACK OF ENHANCED
MOISTURE AND LIFT SINCE WE ARE WITHIN A PURE LES REGIME. SUPPOSE IF
SNOW BANDS CAN STAY ANCHORED IN ONE PLACE THROUGH THE NIGHT...MAY SEE
SEVERAL INCHES OF FLUFFY ACCUMS AS ALL CONVECTIVE DEPTH IS WITHIN THE
DGZ. ALREADY ISSUED LES ADVISORY THROUGH MIDNIGHT FOR ALGER...NORTHERN
SCHOOLCRAFT...AND LUCE COUNTIES. AFTER MIDNIGHT SEEMS THAT DRY AIR
AND LOWER INVERSIONS THAT ARE AFFECTING WESTERN LK SUPERIOR AND CWA
WILL PUT CRIMP IN THE LES INTENSITY OVERNIGHT. WEAK LES WILL CONTINUE
INTO FRIDAY...MAINLY FOR AREAS FAVORED BY WNW-W WINDS...SO ESSENTIALLY
THE SNOW BELTS OF THE KEWEENAW AND ALSO TO THE EAST OF MUNISING.
CONDITIONS EVEN MORE UNFAVORABLE THAN LATER TONIGHT...BUT WITH DGZ
DOMINATING THE CONVECTIVE LAYER STILL COULD SQUEEZE OUT A COUPLE MORE
INCHES OF FLUFF IN PERSISTENT SNOW SHOWERS.
AWAY FM THE LES TONIGHT...LOWERED SKY COVER AND TEMPERATURES AS THE
DRIER AIR SHOULD WIN OUT AS IS OCCURRING UPSTREAM IN MINNESOTA AND
NORTHWEST ONTARIO THIS AFTN. INTERIOR TEMPS SHOULD DIP WELL BLO ZERO
ONCE THE NW WINDS BEHIND THE COLD FRONT BEGIN TO BACK OFF. SHOULD BE
SHARP GRADIENT TO MIN TEMPS AS YOU GET CLOSER TO LK SUPERIOR DUE TO
LINGERING LAKE EFFECT CLOUDS AS 925MB WINDS STAY WNW-NW THROUGH THE
NIGHT. ALSO MAY SEE TEMPS STEADY OR RISE LATE IN THE WEST WITH
ADVANCING DECK OF 6-9KFT ALTOSTRATUS CLOUDS. ANOTHER COOL DAY WITH
AFTN READINGS IN THE TEENS OVER THE CWA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 333 AM EST FRI JAN 2 2015
NAM SHOWS A 500 MB TROUGH OVER THE SOUTHERN PLAINS 12Z SAT WITH A
TROUGH ALSO IN THE NORTHERN ROCKIES. THE TROUGH IN THE SOUTHERN
PLAINS HEADS NORTHEAST WHILE THE NORTHERN ROCKIES TROUGH HEADS EAST
ON SAT AND THEY COMBINE SAT NIGHT TO CARVE OUT A DEEP TROUGH OVER
THE UPPER GREAT LAKES WHICH REMAINS THROUGH SUN NIGHT. NAM AND GFS
SHOW 850-500 MB Q-VECTOR CONVERGENCE MOVING THROUGH ON SAT AND SAT
NIGHT WITH MORE CONVERGENCE RETURNING FOR SUN NIGHT.
DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST. DID INTRODUCE
SOME POPS IN FOR SATURDAY DUE TO LAKE ENHANCEMENT FROM LAKE MICHIGAN
COMING IN AS LAKE SURFACE TEMPERATURES ARE AROUND 2C TO 4C AND 850
MB TEMPERATURES ON SOUTH WINDS ARE AROUND -6C TO -4C AND THAT IS
ENOUGH FOR SOME LIGHT LAKE ENHANCEMENT POSSIBILITIES ANYWAY AS THE
SOUTHERN SHORTWAVE HEADS NORTHEAST AND CLIPS THE SOUTHERN CWA SAT
AFTERNOON. HAVE HIGH POPS IN FOR SAT NIGHT WITH CATEGORICAL POPS AS
THE TWO SYSTEMS COMBINE OVER THE AREA WITH THE HIGHER QPF AMOUNTS
REMAINING TO THE SOUTHEAST OF THE CWA WITH THE CWA FEELING THE
EFFECTS MOST FROM THE NORTHERN SYSTEM. COL AIR WILL MOVE IN FOR SAT
NIGHT INTO SUNDAY. LAKE EFFECT THEN GETS GOING FOR SUNDAY AND WENT
HIGHEST POPS IN NORTH TO NORTHWEST LAKE EFFECT SNOW BELTS.
IN THE EXTENDED...GFS AND ECMWF SHOW A DEEP 500 MB TROUGH OVER MOST
OF THE U.S. 12Z MON WITH VERY COLD AIR ENTRENCHED OVER THE AREA.
THIS UPPER TROUGH REMAINS OVER THE AREA INTO WED BEFORE THE TROUGH
AXIS AND THE COLDEST AIR MOVE OFF TO THE EAST AND SOME MODIFICATION
IN THE AIRMASS BEGINS FOR THU. TEMPERATURES WILL CONTINUE TO BE WELL
BELOW NORMAL AND LAKE EFFECT SNOW WILL CONTINUE FOR THIS FORECAST
PERIOD AS SFC HIGH PRESSURE REMAINS OVER THE CENTRAL PLAINS FOR THIS
PERIOD. LOOKS LIKE THERE COULD BE AN ALBERTA CLIPPER TYPE SYSTEM
PASSING BY FOR THU.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1153 PM EST THU JAN 1 2015
UNDER A COLD AIR MASS AND WNW FLOW...LAKE EFFECT SNOW SHOWERS WILL
AFFECT KCMX THRU THE FIRST HALF OF THIS FCST PERIOD WITH MVFR
CONDITIONS LIKELY PREVAILING. EXPECT SOME PERIODS OF VFR INITIALLY
AS DRIER AIR HAS CAUSED -SHSN TO DIMINISH. TODAY...BACKING WINDS
SHOULD RESULT IN A ZONE OF ENHANCED CONVERGENCE AND A BAND OF
HEAVIER -SHSN LIFTING N AND IMPACTING KCMX LATE MORNING/EARLY AFTN
WITH IFR CONDITIONS POSSIBLE. THEREAFTER...CONDITIONS SHOULD BECOME
VFR AS SW WINDS PUSH LAKE EFFECT N OF THE TERMINAL. AT KIWD...VFR
CONDITIONS WILL PREVAIL OVERNIGHT AS DRY AIR AND WINDS HAVING JUST
ENOUGH OF A WESTERLY COMPONENT WILL KEEP LAKE EFFECT SNOW
SHOWERS/MVFR CONDITIONS N OF THE TERMINAL. WITH WINDS BACKING
FURTHER TODAY...VFR CONDITIONS WILL CONTINUE AT KIWD. AT KSAW...
DOWNSLOPE COMPONENT TO THE WIND OVERNIGHT SHOULD KEEP CONDITIONS
VFR. VFR CONDITIONS WILL THEN CONTINUE THRU TODAY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 508 AM EST FRI JAN 2 2015
THE BUSY MARINE WEATHER WILL PICK UP AGAIN AS WE HEAD INTO THE
WEEKEND...WITH GALES AND HEAVY FREEZING SPRAY RETURNING.
HEAVY FREEZING SPRAY WILL SLOWLY DIMINISH THIS MORNING AS WINDS
DECREASE TO AROUND 20KTS OR LESS. A WEAK TROUGH ACROSS THE E HALF OF
LAKE SUPERIOR WILL BE REPLACED BY A RIDGE TODAY AS THE MAIN HIGH
ACROSS WISCONSIN BUILDS ACROSS MICHIGAN AND EXITS ACROSS LOWER GREAT
LAKES LATE THIS AFTERNOON. A LOW PRESSURE ACROSS THE N PLAINS THIS
EVENING WILL SLIDE SE AND CONSOLIDATE WITH A MID MISSISSIPPI VALLEY
LOW. THE LOW WILL THEN DEEPEN ACROSS S LOWER MICHIGAN SUNDAY
EVENING...AND LAKE HURON EARLY SUNDAY MORNING. THE LOW WILL CONTINUE
INTO S QUEBEC SUNDAY...KEEPING A TROUGH OVER LAKE SUPERIOR SUNDAY
INTO MONDAY. FOR MONDAY AND TUESDAY A RIDGE WILL SETTLE ACROSS THE
PLAINS STATES AS A WEAK LOW DRIFTS OVER THE GREAT LAKES REGION
TUESDAY.
HEAVY FREEZING SPRAY AND GALE WATCHES HAVE BEEN POSTED FOR MUCH OF
LAKE SUPERIOR FROM LATE SATURDAY NIGHT THROUGH SUNDAY...WITH HEAVY
FREEZING SPRAY WARNINGS CONTINUING INTO AT LEAST TUESDAY. WILL NOT
BE SURPRISED IF HEAVY FREEZING SPRAY HEADLINES NEEDED TO BE EXTENDED
BEYOND WEDNESDAY AS THE COLDEST AIR OF THE SEASON SETTLES INTO THE
REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY MORNING FOR
LSZ266-267.
HEAVY FREEZING SPRAY WATCH FROM SUNDAY EVENING THROUGH TUESDAY
EVENING FOR LSZ267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ THIS
MORNING FOR LSZ241>245-263>266.
HEAVY FREEZING SPRAY WATCH FROM LATE SATURDAY NIGHT THROUGH
TUESDAY EVENING FOR LSZ266.
HEAVY FREEZING SPRAY WATCH FROM LATE SATURDAY NIGHT THROUGH
MONDAY AFTERNOON FOR LSZ162.
GALE WATCH FROM LATE SATURDAY NIGHT THROUGH SUNDAY AFTERNOON FOR
LSZ263>265.
HEAVY FREEZING SPRAY WATCH FROM LATE SATURDAY NIGHT THROUGH LATE
MONDAY NIGHT FOR LSZ263>265.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...07
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
333 AM EST FRI JAN 2 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 351 PM EST THU JAN 1 2015
DEEP TROUGH ALOFT CENTERED OVER HUDSON BAY. MULTIPLE SHORTWAVES
MOVING THROUGH THE BASE OF THE TROUGH...BUT AFTER THE SHORTWAVE
MOVED THROUGH THIS MORNING...THERE IS NO LARGER SCALE SUPPORT OVER
THE AREA OR UPSTREAM. PRIMARY COLD FRONT TIED TO THE LAST SHORTWAVE
IS CURRENTLY SINKING SOUTHWARD OVER UPR MICHIGAN. BAND OF HEAVY SNOW
ALONG THE FRONT HAS WORKED THROUGH MARQUETTE AND MUNISING AND IS NOW
ALLIGNED FM SAWYER TO CHATHAM TO SHINGLETON AND TO NEWBERRY AS OF 20Z.
VSBY DOWN TO 1/4SM IN THIS SNOW BAND...BUT IT IS NOT LASTING TOO LONG.
LES OVER THE WESTERN CWA IS SCUFFLING ALONG. IN FACT AFTER THE FRONT
MOVED THROUGH THE KEWEENAW...SPOTS HAVE CLEARED OUT BRIEFLY. HINTS OF
WIND PARALLEL BANDS OVER WESTERN LK SUPERIOR...BUT DRY AIR AND
INVERSIONS BLO 5KFT IS LIMITING THIS DEVELOPMENT. BETTER LES
DEVELOPMENT OVER EASTERN LK SUPERIOR WITH CLOUD STREETS EXTENDING
BACK TO NCNTRL LK SUPERIOR. WILL TAKE A FEW HOURS...BUT DO EXPECT AT
LEAST MODERATE LES TO DEVELOP IN THE NW LOW-LEVEL WINDS INTO EASTERN
CWA. BLYR WINDS OVER 30 KTS INTO THE EVENING WILL RESULT IN BLSN/POOR
VSBY IN THE HEAVIER SNOW BANDS. INVERSIONS 5-8 KFT AND TEMPS AT
INVERSION TOP OF -20C SHOULD AT LEAST RESULT IN SCT HEAVIER SNOW
SHOWERS. 17Z HRRR DOING NICE JOB WITH EXPECTED EVOLUTION THROUGH THE
EVENING...THOUGH IT SEEMS A BIT SLOW WITH TIMING OF HEAVIER SNOW BAND
TIED TO THE FRONT.
ADDITIONAL SNOW AMOUNTS SHOULD STAY IN CHECK GIVEN LACK OF ENHANCED
MOISTURE AND LIFT SINCE WE ARE WITHIN A PURE LES REGIME. SUPPOSE IF
SNOW BANDS CAN STAY ANCHORED IN ONE PLACE THROUGH THE NIGHT...MAY SEE
SEVERAL INCHES OF FLUFFY ACCUMS AS ALL CONVECTIVE DEPTH IS WITHIN THE
DGZ. ALREADY ISSUED LES ADVISORY THROUGH MIDNIGHT FOR ALGER...NORTHERN
SCHOOLCRAFT...AND LUCE COUNTIES. AFTER MIDNIGHT SEEMS THAT DRY AIR
AND LOWER INVERSIONS THAT ARE AFFECTING WESTERN LK SUPERIOR AND CWA
WILL PUT CRIMP IN THE LES INTENSITY OVERNIGHT. WEAK LES WILL CONTINUE
INTO FRIDAY...MAINLY FOR AREAS FAVORED BY WNW-W WINDS...SO ESSENTIALLY
THE SNOW BELTS OF THE KEWEENAW AND ALSO TO THE EAST OF MUNISING.
CONDITIONS EVEN MORE UNFAVORABLE THAN LATER TONIGHT...BUT WITH DGZ
DOMINATING THE CONVECTIVE LAYER STILL COULD SQUEEZE OUT A COUPLE MORE
INCHES OF FLUFF IN PERSISTENT SNOW SHOWERS.
AWAY FM THE LES TONIGHT...LOWERED SKY COVER AND TEMPERATURES AS THE
DRIER AIR SHOULD WIN OUT AS IS OCCURRING UPSTREAM IN MINNESOTA AND
NORTHWEST ONTARIO THIS AFTN. INTERIOR TEMPS SHOULD DIP WELL BLO ZERO
ONCE THE NW WINDS BEHIND THE COLD FRONT BEGIN TO BACK OFF. SHOULD BE
SHARP GRADIENT TO MIN TEMPS AS YOU GET CLOSER TO LK SUPERIOR DUE TO
LINGERING LAKE EFFECT CLOUDS AS 925MB WINDS STAY WNW-NW THROUGH THE
NIGHT. ALSO MAY SEE TEMPS STEADY OR RISE LATE IN THE WEST WITH
ADVANCING DECK OF 6-9KFT ALTOSTRATUS CLOUDS. ANOTHER COOL DAY WITH
AFTN READINGS IN THE TEENS OVER THE CWA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 333 AM EST FRI JAN 2 2015
NAM SHOWS A 500 MB TROUGH OVER THE SOUTHERN PLAINS 12Z SAT WITH A
TROUGH ALSO IN THE NORTHERN ROCKIES. THE TROUGH IN THE SOUTHERN
PLAINS HEADS NORTHEAST WHILE THE NORTHERN ROCKIES TROUGH HEADS EAST
ON SAT AND THEY COMBINE SAT NIGHT TO CARVE OUT A DEEP TROUGH OVER
THE UPPER GREAT LAKES WHICH REMAINS THROUGH SUN NIGHT. NAM AND GFS
SHOW 850-500 MB Q-VECTOR CONVERGENCE MOVING THROUGH ON SAT AND SAT
NIGHT WITH MORE CONVERGENCE RETURNING FOR SUN NIGHT.
DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST. DID INTRODUCE
SOME POPS IN FOR SATURDAY DUE TO LAKE ENHANCEMENT FROM LAKE MICHIGAN
COMING IN AS LAKE SURFACE TEMPERATURES ARE AROUND 2C TO 4C AND 850
MB TEMPERATURES ON SOUTH WINDS ARE AROUND -6C TO -4C AND THAT IS
ENOUGH FOR SOME LIGHT LAKE ENHANCEMENT POSSIBILITIES ANYWAY AS THE
SOUTHERN SHORTWAVE HEADS NORTHEAST AND CLIPS THE SOUTHERN CWA SAT
AFTERNOON. HAVE HIGH POPS IN FOR SAT NIGHT WITH CATEGORICAL POPS AS
THE TWO SYSTEMS COMBINE OVER THE AREA WITH THE HIGHER QPF AMOUNTS
REMAINING TO THE SOUTHEAST OF THE CWA WITH THE CWA FEELING THE
EFFECTS MOST FROM THE NORTHERN SYSTEM. COL AIR WILL MOVE IN FOR SAT
NIGHT INTO SUNDAY. LAKE EFFECT THEN GETS GOING FOR SUNDAY AND WENT
HIGHEST POPS IN NORTH TO NORTHWEST LAKE EFFECT SNOW BELTS.
IN THE EXTENDED...GFS AND ECMWF SHOW A DEEP 500 MB TROUGH OVER MOST
OF THE U.S. 12Z MON WITH VERY COLD AIR ENTRENCHED OVER THE AREA.
THIS UPPER TROUGH REMAINS OVER THE AREA INTO WED BEFORE THE TROUGH
AXIS AND THE COLDEST AIR MOVE OFF TO THE EAST AND SOME MODIFICATION
IN THE AIRMASS BEGINS FOR THU. TEMPERATURES WILL CONTINUE TO BE WELL
BELOW NORMAL AND LAKE EFFECT SNOW WILL CONTINUE FOR THIS FORECAST
PERIOD AS SFC HIGH PRESSURE REMAINS OVER THE CENTRAL PLAINS FOR THIS
PERIOD. LOOKS LIKE THERE COULD BE AN ALBERTA CLIPPER TYPE SYSTEM
PASSING BY FOR THU.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1153 PM EST THU JAN 1 2015
UNDER A COLD AIR MASS AND WNW FLOW...LAKE EFFECT SNOW SHOWERS WILL
AFFECT KCMX THRU THE FIRST HALF OF THIS FCST PERIOD WITH MVFR
CONDITIONS LIKELY PREVAILING. EXPECT SOME PERIODS OF VFR INITIALLY
AS DRIER AIR HAS CAUSED -SHSN TO DIMINISH. TODAY...BACKING WINDS
SHOULD RESULT IN A ZONE OF ENHANCED CONVERGENCE AND A BAND OF
HEAVIER -SHSN LIFTING N AND IMPACTING KCMX LATE MORNING/EARLY AFTN
WITH IFR CONDITIONS POSSIBLE. THEREAFTER...CONDITIONS SHOULD BECOME
VFR AS SW WINDS PUSH LAKE EFFECT N OF THE TERMINAL. AT KIWD...VFR
CONDITIONS WILL PREVAIL OVERNIGHT AS DRY AIR AND WINDS HAVING JUST
ENOUGH OF A WESTERLY COMPONENT WILL KEEP LAKE EFFECT SNOW
SHOWERS/MVFR CONDITIONS N OF THE TERMINAL. WITH WINDS BACKING
FURTHER TODAY...VFR CONDITIONS WILL CONTINUE AT KIWD. AT KSAW...
DOWNSLOPE COMPONENT TO THE WIND OVERNIGHT SHOULD KEEP CONDITIONS
VFR. VFR CONDITIONS WILL THEN CONTINUE THRU TODAY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 351 PM EST THU JAN 1 2015
NW GALES DIMINISH THIS EVENING OVER THE EAST HALF. HEAVY FREEZING
SPRAY WILL ALSO END LATE TONIGHT. WINDS SETTLE DOWN TO LESS THAN 25
KTS LATER TONIGHT THROUGH FRIDAY NIGHT AS HIGH PRESSURE MOVES
OVERHEAD. EXPECT A BRIEF PERIOD OF STRONGER SE WINDS ON SATURDAY...BUT
THE BETTER CHANCE OF STRONGER WINDS WILL BE LATE SATURDAY NIGHT INTO
SUNDAY AS NORTH TO NORTHWEST WINDS INCREASE AS A LOW PRESSURE SYSTEM
LIFTS OVER THE GREAT LAKES THEN MOVES EAST OVER QUEBEC. BEST SHOT OF
GALES WILL BE OVER THE EAST HALF OF LK SUPERIOR ON SUNDAY. NW WINDS
TO 30 KTS WILL LINGER OVER MUCH OF LK SUPERIOR INTO EARLY NEXT WEEK
BEHIND THE WEEKEND SYSTEM. MORE HEAVY FREEZING SPRAY IS EXPECTED LATE
THIS WEEKEND INTO EARLY NEXT WEEK AS ARCTIC AIR FLOWS ACROSS LK
SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY MORNING FOR
LSZ266-267.
HEAVY FREEZING SPRAY WATCH FROM SUNDAY EVENING THROUGH TUESDAY
EVENING FOR LSZ267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ THIS
MORNING FOR LSZ241>245-263-264-266.
HEAVY FREEZING SPRAY WATCH FROM LATE SATURDAY NIGHT THROUGH
TUESDAY EVENING FOR LSZ266.
GALE WATCH FROM LATE SATURDAY NIGHT THROUGH SUNDAY AFTERNOON FOR
LSZ263>265.
HEAVY FREEZING SPRAY WATCH FROM LATE SATURDAY NIGHT THROUGH LATE
MONDAY NIGHT FOR LSZ263>265.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...07
AVIATION...ROLFSON
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1156 PM EST THU JAN 1 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 351 PM EST THU JAN 1 2015
DEEP TROUGH ALOFT CENTERED OVER HUDSON BAY. MULTIPLE SHORTWAVES
MOVING THROUGH THE BASE OF THE TROUGH...BUT AFTER THE SHORTWAVE
MOVED THROUGH THIS MORNING...THERE IS NO LARGER SCALE SUPPORT OVER
THE AREA OR UPSTREAM. PRIMARY COLD FRONT TIED TO THE LAST SHORTWAVE
IS CURRENTLY SINKING SOUTHWARD OVER UPR MICHIGAN. BAND OF HEAVY SNOW
ALONG THE FRONT HAS WORKED THROUGH MARQUETTE AND MUNISING AND IS NOW
ALLIGNED FM SAWYER TO CHATHAM TO SHINGLETON AND TO NEWBERRY AS OF 20Z.
VSBY DOWN TO 1/4SM IN THIS SNOW BAND...BUT IT IS NOT LASTING TOO LONG.
LES OVER THE WESTERN CWA IS SCUFFLING ALONG. IN FACT AFTER THE FRONT
MOVED THROUGH THE KEWEENAW...SPOTS HAVE CLEARED OUT BRIEFLY. HINTS OF
WIND PARALLEL BANDS OVER WESTERN LK SUPERIOR...BUT DRY AIR AND
INVERSIONS BLO 5KFT IS LIMITING THIS DEVELOPMENT. BETTER LES
DEVELOPMENT OVER EASTERN LK SUPERIOR WITH CLOUD STREETS EXTENDING
BACK TO NCNTRL LK SUPERIOR. WILL TAKE A FEW HOURS...BUT DO EXPECT AT
LEAST MODERATE LES TO DEVELOP IN THE NW LOW-LEVEL WINDS INTO EASTERN
CWA. BLYR WINDS OVER 30 KTS INTO THE EVENING WILL RESULT IN BLSN/POOR
VSBY IN THE HEAVIER SNOW BANDS. INVERSIONS 5-8 KFT AND TEMPS AT
INVERSION TOP OF -20C SHOULD AT LEAST RESULT IN SCT HEAVIER SNOW
SHOWERS. 17Z HRRR DOING NICE JOB WITH EXPECTED EVOLUTION THROUGH THE
EVENING...THOUGH IT SEEMS A BIT SLOW WITH TIMING OF HEAVIER SNOW BAND
TIED TO THE FRONT.
ADDITIONAL SNOW AMOUNTS SHOULD STAY IN CHECK GIVEN LACK OF ENHANCED
MOISTURE AND LIFT SINCE WE ARE WITHIN A PURE LES REGIME. SUPPOSE IF
SNOW BANDS CAN STAY ANCHORED IN ONE PLACE THROUGH THE NIGHT...MAY SEE
SEVERAL INCHES OF FLUFFY ACCUMS AS ALL CONVECTIVE DEPTH IS WITHIN THE
DGZ. ALREADY ISSUED LES ADVISORY THROUGH MIDNIGHT FOR ALGER...NORTHERN
SCHOOLCRAFT...AND LUCE COUNTIES. AFTER MIDNIGHT SEEMS THAT DRY AIR
AND LOWER INVERSIONS THAT ARE AFFECTING WESTERN LK SUPERIOR AND CWA
WILL PUT CRIMP IN THE LES INTENSITY OVERNIGHT. WEAK LES WILL CONTINUE
INTO FRIDAY...MAINLY FOR AREAS FAVORED BY WNW-W WINDS...SO ESSENTIALLY
THE SNOW BELTS OF THE KEWEENAW AND ALSO TO THE EAST OF MUNISING.
CONDITIONS EVEN MORE UNFAVORABLE THAN LATER TONIGHT...BUT WITH DGZ
DOMINATING THE CONVECTIVE LAYER STILL COULD SQUEEZE OUT A COUPLE MORE
INCHES OF FLUFF IN PERSISTENT SNOW SHOWERS.
AWAY FM THE LES TONIGHT...LOWERED SKY COVER AND TEMPERATURES AS THE
DRIER AIR SHOULD WIN OUT AS IS OCCURRING UPSTREAM IN MINNESOTA AND
NORTHWEST ONTARIO THIS AFTN. INTERIOR TEMPS SHOULD DIP WELL BLO ZERO
ONCE THE NW WINDS BEHIND THE COLD FRONT BEGIN TO BACK OFF. SHOULD BE
SHARP GRADIENT TO MIN TEMPS AS YOU GET CLOSER TO LK SUPERIOR DUE TO
LINGERING LAKE EFFECT CLOUDS AS 925MB WINDS STAY WNW-NW THROUGH THE
NIGHT. ALSO MAY SEE TEMPS STEADY OR RISE LATE IN THE WEST WITH
ADVANCING DECK OF 6-9KFT ALTOSTRATUS CLOUDS. ANOTHER COOL DAY WITH
AFTN READINGS IN THE TEENS OVER THE CWA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 408 PM EST THU JAN 1 2015
A PROMINENT RIDGE GRADUALLLY BUILDING TO THE EAST INTO WRN NOAM WILL
MAINTAIN A BROAD TROUGH FROM CENTRAL CANADA INTO THE GREAT LAKES.
AFTER LOW PRESSURE SYSTEM LIFTS NE FROM THE CNTRL GREAT LAKES...MUCH
COLDER AIR WILL MOVE INTO THE REGION AND REMAIN THROUGH MUCH OF NEXT
WEEK KEEPING LES GOING FOR MAINLY NW TO WNW FLOW FAVORED LOCATIONS.
FRI NIGHT AND SAT...A BROAD 850-600 MB WARM ADVECTION 280K-295
ISENTROPIC LIFT ZONE WILL DEVELOP FROM THE NRN PLAINS INTO NRN MN AND NRN
LAKE SUPERIOR IN RESPONSE TO THE DEVELOPING TROUGH OVER THE PLAINS
AND UPPER LEVEL DIV WITH THE RIGHT ENTRANCE OF A 250-300 MB JET
STREAK THROUGH NRN ONTARIO. THE MODELS KEEP MOST OF THE PCPN WITH
THIS FEATURE NORTH OF UPPER MI. WAA WILL RAISE TEMPS AT OR
SLIGHTLY ABOVE AVERAGE WITH READINGS IN THE MID TO UPPER 20S.
SAT NIGHT INTO SUN...A SHRTWV ORIGINATING FROM THE GULF OF ALASKA
DIVING INTO THE WRN CONUS TROUGH WILL HELP EJECT THE SW CLOSED LOW
NE TOWARD THE GREAT LAKES. THE 12Z GFS/ECMWF ALONG WITH ENSEMBLES
FAVOR A LOW TRACK FROM THE SRN END OF LAKE MI TO CNTRL LAKE HURON
AND THEN NE INTO QUEBEC. STRONG 700-300 MB QVECTOR CONV ASSOCIATED
WITH THE SHRTWV WILL SUPPORT A BROAD AREA OF SNOW FROM WI INTO UPPER
MI BY LATE SAT AND ESPECIALLY LATE SAT NIGHT. MDLS CONSENSUS QPF IN
THE 0.20 TO 0.35 INCH RANGE WITH SLR VALUES AROUND 14/1 WILL SUPPORT
POTENTIAL FOR 3 TO 6 INCHES BY 18Z/SUN. ADDITIONAL SUPPORT FOR
HEAVIER SNOW IS EXPECTED OVER THE NORTH CYCLONIC NRLY FLOW AND 850
MB TEMPS DROPPING FROM -10C TO -15C BY 12Z TO -14C TO -19C BY 18Z
WILL RESULT HIGHER AMOUNTS THROUGH LAKE ENHANCEMENT. BY SUN
AFTERNOON THE DEEPER MOISTURE AND SYNOPTIC SUPPORT LIFT QUICKLY WITH
A TRANSITION TO LIGHTER PURE LES.
SUN NIGHT INTO MON...VERY COLD ARCTIC AIR WILL PLUNGE INTO THE
REGION WITH 850 MB TEMPS DROPPING TO AROUND -27C BY 12Z MON. THIS
WILL LOWER THE DGZ TOWARD THE SFC AND REDUCE POTENTIAL FOR
SIGNIFICANT LES. HOWEVER...WIND CHILL WITH A MORE WRLY SFC WIND
COMPONENT RESULTING FROM LAKE INDUCED TROUGHING WILL ALLOW TEMPS TO
DROP OFF OVER MUCH OF THE CWA. WIND CHILL VALUES IN THE -20 TO -35
RANGE ARE EXPECTED.
TUE-THU...A FEW CLIPPER SHRTWVS ARE LIKELY TO MOVE THROUGH THE REGION WITH
NW-NNW MID LEVEL FLOW IN PLACE. THIS MAY BRING REINFORCING BOUTS OF
COLD AIR AND SHIFT THE POSITIONS OF THE HEAVIER LES BANDS. TEMPS MAY
MODERATE SLIGHTLY IF SFC WINDS VEER MORE TO THE NW WITH MORE MARINE
MODIFICATION. HOWEVER...WIND CHILLS MAY REMAIN NEAR ADVY THRESHOLD
DURING THE LATER NIGHT INTO MORNING HOURS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1153 PM EST THU JAN 1 2015
UNDER A COLD AIR MASS AND WNW FLOW...LAKE EFFECT SNOW SHOWERS WILL
AFFECT KCMX THRU THE FIRST HALF OF THIS FCST PERIOD WITH MVFR
CONDITIONS LIKELY PREVAILING. EXPECT SOME PERIODS OF VFR INITIALLY
AS DRIER AIR HAS CAUSED -SHSN TO DIMINISH. TODAY...BACKING WINDS
SHOULD RESULT IN A ZONE OF ENHANCED CONVERGENCE AND A BAND OF
HEAVIER -SHSN LIFTING N AND IMPACTING KCMX LATE MORNING/EARLY AFTN
WITH IFR CONDITIONS POSSIBLE. THEREAFTER...CONDITIONS SHOULD BECOME
VFR AS SW WINDS PUSH LAKE EFFECT N OF THE TERMINAL. AT KIWD...VFR
CONDITIONS WILL PREVAIL OVERNIGHT AS DRY AIR AND WINDS HAVING JUST
ENOUGH OF A WESTERLY COMPONENT WILL KEEP LAKE EFFECT SNOW
SHOWERS/MVFR CONDITIONS N OF THE TERMINAL. WITH WINDS BACKING
FURTHER TODAY...VFR CONDITIONS WILL CONTINUE AT KIWD. AT KSAW...
DOWNSLOPE COMPONENT TO THE WIND OVERNIGHT SHOULD KEEP CONDITIONS
VFR. VFR CONDITIONS WILL THEN CONTINUE THRU TODAY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 351 PM EST THU JAN 1 2015
NW GALES DIMINISH THIS EVENING OVER THE EAST HALF. HEAVY FREEZING
SPRAY WILL ALSO END LATE TONIGHT. WINDS SETTLE DOWN TO LESS THAN 25
KTS LATER TONIGHT THROUGH FRIDAY NIGHT AS HIGH PRESSURE MOVES
OVERHEAD. EXPECT A BRIEF PERIOD OF STRONGER SE WINDS ON SATURDAY...BUT
THE BETTER CHANCE OF STRONGER WINDS WILL BE LATE SATURDAY NIGHT INTO
SUNDAY AS NORTH TO NORTHWEST WINDS INCREASE AS A LOW PRESSURE SYSTEM
LIFTS OVER THE GREAT LAKES THEN MOVES EAST OVER QUEBEC. BEST SHOT OF
GALES WILL BE OVER THE EAST HALF OF LK SUPERIOR ON SUNDAY. NW WINDS
TO 30 KTS WILL LINGER OVER MUCH OF LK SUPERIOR INTO EARLY NEXT WEEK
BEHIND THE WEEKEND SYSTEM. MORE HEAVY FREEZING SPRAY IS EXPECTED LATE
THIS WEEKEND INTO EARLY NEXT WEEK AS ARCTIC AIR FLOWS ACROSS LK
SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MIZ006-
007-085.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 AM EST FRIDAY FOR LSZ265-
267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ FRIDAY
FOR LSZ241>245-263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...JLB
AVIATION...ROLFSON
MARINE...JLA
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
554 AM CST FRI JAN 2 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 255 AM CST FRI JAN 2 2015
A QUIET SHORT TERM PERIOD FOR TODAY AND TONIGHT. MAIN CHANGE TO
THE FORECAST WAS TO INCREASE SKY COVER AS A SOLID DECK OF
STRATUS CONTINUES BUILDING IN FROM THE WEST. THIS TREND IS
EXPECTED TO CONTINUE...WITH THE SKY BECOMING INCREASINGLY CLOUDY
FROM WEST TO EAST TODAY. SURFACE HIGH PRESSURE SLIDING EAST ACROSS
THE FA EARLY THIS MORNING HAS ALLOWED SOUTHERLY FLOW WITH WAA TO
ENTER WESTERN MN...WHICH IS CO-LOCATED WITH THE STRATUS DECK.
TEMPERATURES ARE BEING HELD IN THE UPPER TEENS FOR MUCH OF THAT
AREA...WHERE SINGLE DIGITS ON EITHER SIDE OF ZERO WHERE PREVALENT
FURTHER EAST UNDER CLEAR SKIES EARLY THIS MORNING.
FOR TODAY...AS THE HIGH CONTINUES EAST...A WEAK WARM FRONT WILL
LIFT THROUGH THE STATE AHEAD OF A LOW PRESSURE AREA THAT WILL BE
DROPPING SOUTHEAST OUT OF SOUTHWESTERN CANADA. WHILE SLIGHTLY
COOLER TEMPERATURES THAN YESTERDAY ARE EXPECTED...TODAY`S HIGHS
WILL BE NEAR NORMAL FOR THIS TIME OF YEAR. THE LOW WILL ADVANCES
SOUTHEAST TO NEAR FARGO BY TOMORROW MORNING...WITH ACCUMULATING
SNOW ONGOING TO THE NORTH OF THE LOW AT THAT TIME. BEST FORCING
STILL REMAINS NORTH OF THE FA...SO KEPT POPS OUT FOR THE SHORT
TERM FORECAST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 255 AM CST FRI JAN 2 2015
MAIN CONCERNS FOR THE LONG TERM ARE...A CLIPPER-TYPE SYSTEM FOR
SAT AFTN-EVE...VERY COLD AIR FOR THE FIRST HALF OF NEXT WEEK...
AND ANOTHER CLIPPER-TYPE SYSTEM MON NIGHT INTO EARLY TUE.
SPLIT UPPER LEVEL FLOW WILL PRESENT TWO DISTINCT AREAS OF LOW
PRESSURE FOR THE CENTRAL CONUS...ONE A CLIPPER-TYPE SYSTEM OVER
THE NRN TIER STATES AND ANOTHER DEVELOPING OVER THE TX/OK
PANHANDLES. THE FOCUS WILL BE ON THE NRN STREAM SYSTEM AS GOOD
MODEL AGREEMENT PUTS THE SRN STREAM SYSTEM TOO FAR DISPLACED TO
THE S...EVEN WHILE IT IS MOVING NE...TO BE A FACTOR FOR SENSIBLE
WX IN MN AND WRN WI. THE PHASING OF THESE TWO STREAMS WILL TAKE
PLACE OVER THE CENTRAL-ERN GREAT LAKES...THUS NOT FACTORING INTO
THE WX IN THIS AREA. THEREFORE...FOCUSING ON THE NRN STREAM
SYSTEM...THIS SYSTEM WILL DROP ACRS THE REGION SAT AFTN THRU SAT
EVE. THOUGH THE BEST FORCING WILL BE N OF THE AREA...PRODUCING
MORE SNOWFALL OVER NRN MN THAN CENTRAL-SRN MN...A VERY TIGHT PRES
GRADIENT ON THE BACKSIDE OF THIS SYSTEM WILL LIKELY PRODUCE
BLOWING/DRIFTING SNOW WITH EVEN MINOR SNOWFALL ACCUMULATIONS ACRS
MUCH OF THE WFO MPX CWFA. SUSTAINED SPEEDS WILL LIKELY INCRS TO
THE 25-35 MPH RANGE WITH GUSTS UPWARDS OF 45 MPH.
ONCE THIS SYSTEM PASSES ACRS...VERY STRONG CAA WILL COMMENCE AS
BOTH SFC AND UPR LVL FLOW BECOMES PREDOMINANTLY NW IN ADVANCE OF A
1046MB HIGH DROPPING IN FROM WRN CANADA. HIGHS WILL DROP TO THE
SINGLE DIGITS...IF NOT JUST BELOW ZERO...WHILE LOW TEMPERATURES
DROP TO NEARLY -20 SAT NIGHT THRU TUE NIGHT. THE STRONG WINDS ON
THE BACKSIDE OF THE SYSTEM WILL LIKELY PRODUCE WIND CHILL VALUES
IN THE -30 TO -40 DEGREE RANGE FOR SAT NIGHT THRU SUN NIGHT...AND
AS LOW AS -25 GOING INTO MON NIGHT AS WINDS DROP OFF.
THE NEXT SYSTEM OF CONSEQUENCE COMES LATE DAY MON INTO MON NIGHT.
NOTICEABLE TIMING DIFFERENCES HAVE THE GFS MUCH FASTER THAN A
COMPOSITE OF THE ECMWF/GEM/DGEX FOR A CLIPPER-TYPE SYSTEM SWINGING
EWD THRU THE DAKOTAS INTO THE UPR MISS RIVER VALLEY. MAIN CHC FOR
PRECIP COMES MON NIGHT...BUT SOME -SN MAY DEVELOP PRIOR TO 00Z IN
WRN MN SO HAVE KEPT CHC POPS OUT THAT WAY FOR MON AFTN. MINOR SNOW
ACCUMULATIONS LOOK TO OCCUR FROM THIS SYSTEM...BUT THE MAIN ISSUE
WILL CONTINUE TO BE THE VERY COLD AIR IN PLACE...REINFORCED BY
ANOTHER BOUT OF CAA BEHIND THIS SYSTEM WHICH WILL AGAIN FORCE
SINGLE DIGIT HIGHS AND SUB-ZERO LOWS MIDWEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 541 AM CST FRI JAN 2 2015
AS ALLUDED TO LAST ISSUANCE...WIDESPREAD STRATUS DECK CONTINUES TO
ADVANCE EASTWARD FASTER THAN ANY GUIDANCE WOULD LIKE TO INDICATE.
KEPT A GENERALLY PESSIMISTIC FORECAST GOING FOR TODAY AND
TONIGHT. THE STRATUS WILL OVERTAKE MSP VERY SOON THIS MORNING AND
CONTINUE EASTWARD THROUGH WESTERN WISCONSIN THROUGH THE DAY AS
THE SURFACE HIGH CONTINUES EASTWARD. THE PROBLEM IS THE CEILING
HEIGHT WITH THIS STRATUS...IT CONTINUES TO TEETER ON THE EDGE OF
MVFR/VFR WITH THE NORTHERN HALF OF THE CWA SEEING CIGS JUST ABOVE
3K FT...BUT SOUTHERN MN BETWEEN 025-030. FURTHER NORTHWEST
HOWEVER...CIGS ARE MVFR TOO SO EXPECTING THAT TO EVENTUALLY REACH
AXN AND STC. THE RAP SEEMS TO HAVE THE BEST HANDLE ON THE CLOUDS
EARLY THIS MORNING...SO THE FORECAST WAS LARGELY BASED ON A
COMBINATION OF RAP FORECAST SOUNDINGS AND CURRENT SATELLITE
TRENDS. CEILINGS MAY LOWER TO AROUND 1K FT TONIGHT THROUGH
SATURDAY MORNING...BUT A DRY TONGUE TO THE SOUTH A CLIPPER SYSTEM
MAY SCOUR CLOUDS OUT FOR A TIME SATURDAY MORNING. SO...A LOW
CONFIDENCE FORECAST FOR TONIGHT AND TOMORROW.
KMSP...STRATUS JUST TO THE WEST AT THIS TIME...AND IT LOOKS LIKE
MSP WILL BE RIGHT ON THE EDGE OF MVFR/VFR CIGS THIS MORNING...SO
EXPECT THE CEILING TO BOUNCE AROUND 3K FEET BEFORE LOWERING THIS
AFTERNOON AND EVENING.
/OUTLOOK FOR KMSP/
SAT NGT...MVFR WITH -SN/BLSN. WINDS NW AT 20G35KTS.
SUN...MVFR LIKELY. WINDS NW AT 15G25KTS.
MON...VFR. WINDS W AT 10G15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...JPC
AVIATION...SPD
AREA FORECAST DISCUSSION
NWS JACKSON MS
1018 AM CST FRI JAN 2 2015
...WET PATTERN TO CONTINUE THROUGH FIRST HALF OF WEEKEND...WITH
INCREASING RISK FOR ACTIVE THUNDERSTORMS ON SATURDAY...
.UPDATE...MAIN ADJUSTMENTS ARE TO LOWER POPS AND INCLUDE DRIZZLE
TODAY. ALSO ADJUSTED TEMPS BASED ON LATEST HRRR.
&&
.SHORT TERM...
RAIN IS GRADUALLY TAPIERING OFF FROM THE WEST ACROSS NORTHERN HALF OF
AREA AFTER A WIDESPREAD MODERATE TO HEAVY RAIN EVENT LAST 24
HOURS...WITH MOST LOCATIONS IN NORTHERN HALF OF AREA PICKING UP 1 TO
3 INCHES OF RAIN. STEADIEST RAIN IS CURRENTLY WORKING EAST ACROSS HWY
82 CORRIDOR EAST OF I-55. REST OF AREA IS SEEING LOTS OF LOW
CLOUDS/DRIZZLE WITH SOME PATCHY -RA AND SHRA. LATEST HRRR RUNS IMPLY
THAT ONCE MAIN BATCH OF RAIN PUSHES EAST THIS DZ/SHRA REGIME WILL
DOMINATE REST OF TODAY...AND HAVE ADJUSTED POPS AND WX ACCORDINGLY.
COULD BE SOME UPTICK IN CONVECTIVE COVERAGE AND MAYBE A FEW TSRA LATE
TODAY AS LOW LEVEL FLOW BACKS AROUND A BIT AGAIN AND ISENTROPIC
ASCENT INCREASES.
TEMPERATURES WILL NOT MOVE MUCH OVER MOST OF THE AREA TODAY AS
STAGNANT COOL HIGH PRESSURE REMAINS OVERHEAD...GRADUALLY WEAKENING.
EXCEPTION SHOULD BE DOWN IN THE HWY 98 CORRIDOR. LATEST VISIBLE
IMAGERY SHOWS THAT SOME PEEKS OF SUN SHOULD OCCUR DOWN THERE...AND
WARM FRONTAL BOUNDARY WILL BE SHIFTING SLOWLY NW USHERING IN WARMER
AIR. HRRR ACTUALLY PUSHES TEMPS INTO THE 70S IN THE HATTIESBURG/
PURVIS AREAS THIS AFTERNOON. WHILE I DID NOT TAKE THE GRIDS THAT
WARM...DID USE THE HRRR AS A STARTING POINT TO ADJUST TEMPS UP
SEVERAL DEGS IN THE SE AND TRY TO BEST DEPICT STRONG THERMAL GRADIENT
ACROSS AREA.
WITH REGARD TO SATURDAY SYSTEM...MODELS CONTINUE IN GENERAL AGREEMENT
THAT WE WILL BE ON THE SOUTHERN PERIPHERY OF EJECTING SW CONUS UPPER
SYSTEM. STILL APPEARS AS THOUGH INSTABILITY AND SHEAR WILL INCREASE
DRAMATICALLY STARTING LATE TONIGHT INTO SAT MORNING TO SUPPORT A RISK
OF SEVERE STORMS...ALONG WITH HEAVY RAINFALL. WILL BE COORDINATING
WITH SPC AND ADJUSTING HAZARD GRAPHICS/HWO THIS AFTERNOON...AS WELL
AS EVALUATING HYDRO SITUATION FOR ANY POTENTIAL FLOOD WATCHES. MORE
DETAILS IN THE AFTERNOON DISCUSSION.
&&
.AVIATION...
PER LASTEST OBS/SATELLITE TRENDS AND SREF/HRRR GUIDANCE...INCREASING
WARM AND MOIST AIR WILL BRING WIDESPREAD LOW STRATUS AND AREAS OF
FOG/DRIZZLE WITH IFR AND OCCASIONALLY LIFR RESTRICTIONS THROUGH
TONIGHT. THERE HAS BEEN SOME CIG BREAK-UP NEAR HBG...BUT EXPECT
LOWER CIGS TO RETURN BY LATE AFTN. AREAS OF SHRA/TSRA CAN BE
EXPECTED...BUT THE BULK OF TSRA ACTIVITY SHOULD HOLD OFF UNTIL
SATURDAY. AWAY FROM TSRA...LOOK FOR PREVAILING CIGS TO LIFT SATURDAY
MORNING TO MVFR CATEGORY AS STRONGER MIXING OCCURS AHEAD OF AN
APPROACHING COLD FRONT. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 55 55 70 47 / 66 56 95 71
MERIDIAN 52 53 70 51 / 68 67 83 90
VICKSBURG 54 55 69 44 / 57 69 100 40
HATTIESBURG 68 61 72 55 / 54 54 72 90
NATCHEZ 58 61 70 46 / 54 68 99 43
GREENVILLE 49 48 64 41 / 65 74 100 27
GREENWOOD 50 49 67 44 / 100 69 100 54
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AEG/EC
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
952 PM CST Sat Jan 3 2015
.UPDATE:
Issued at 938 PM CST Sat Jan 3 2015
Eastern Missouri and western Illinois are stuck in a weak cyclonic
lobe of surface pressure at this time, with the old frontal system
well to the east in the OH/TN Valley region and the first Arctic
cold front pushing into northwest MO. This weak flow has resulted
in fog and quite a bit of drizzle, some of which is measurable.
Meanwhile to the west, the coverage of precipitation is increasing
across western MO in response to large scale forcing/ascent
associated with the shortwave across eastern KS into northeast OK.
The changeover to snow in western MO is taking its time with temps
still in the mid-upper 30s. Present indications are the
aforementioned shortwave will rotate east northeast tonight in
association with the lifting and weakening upper trof. This will
result in precipitation spreading from western MO across central
and northeast MO into western IL through the late evening and
overnight, with St. Louis on the tail end. I`m not real excited
about seeing much measurable snowfall given the slow changeover,
marginal temps, and in general a weakening system. Best odds of
accumulations will be in north central/northeast MO where around
an inch is possible. The Arctic front itself will continue to
surge southeast for the remainder of the night into early Saturday
morning with gusty northwest winds ushering some mighty chilly air
into the area and scouring out the soupy IFR conditions. Cloudy
skies, falling temps, and flurries likely through the day on
Saturday.
Glass
&&
.SHORT TERM: (Through Sunday)
Issued at 339 AM CST Sat Jan 3 2015
Forecast on track with upper level low/shortwave moving northeast
across the region this evening. Precipitation associated with this
feature should start as rain and then transition to snow before
ending. Best chance of an inch of accumulation will be across the
far northern CWA. Otherwise, some mood snow showers or flurries
will be the rule as colder air pours into the region overnight
into Sunday morning. Sunday will be breezy and much colder with
temperatures continuing to slowly fall throughout the day.
.LONG TERM: (Monday through Next Saturday)
Issued at 230 PM CST Sat Jan 3 2015
Temperature will moderate some on Monday as a clipper system
tracks north of the area. Have kept the forecast dry based on the
consensus track of the system to our north.
Pattern really amplifies behind this clipper with a very strong
arctic high pressure system moving into the mid section of the
country for midweek. This will be the coldest air we have seen this
winter season. Expect temperatures to be at 20 to 30 degrees below
normal Tuesday night through Thursday. As previous forecaster
stated, below zero temperatures are likely for a large portion of
the area Thursday morning as the center of the anticyclone will be
parked over head. The latest MEX guidance has below zero
temperatures at STL both Wednesday and Thursday morning - WITH NO
SNOW COVER. Have trended the forecast colder based on the latest
model data and expect wind chill values will warrent advisories to
be issued in the future.
Airmass really struggles to moderate before the next storm system
moves toward the area late next week and weekend. This could set the
stage for a more widespread winter weather event across the CWA
Friday night/Saturday morning. For now will keep chance POPs for
snow as the ECWMF does not depict as deep/strong of a
shortwave/surface reflection at this time.
CVKING
&&
.AVIATION: (For the 00z TAFs through 00z Sunday Evening)
Issued at 453 PM CST Sat Jan 3 2015
Closed upper low over north central Oklahoma opening as it lifts
northeast. Current models reflect this in the precipitation
forecast with the precipitation diminishing as it lifts northeast.
The latest HRRR is also not bullish on the precipitation with most
of it gone by 07z. A period of light snow is certainly possible
for COU and UIN with a 03z to 07z for COU and and hour later for
UIN. Northwest wind picks up from 06z to 12z west to east as the
surfact low moves northeast out of the area. IFR ceilings should
lift to MVFR as the wind picks up with VFR beginning to show up
after 20z.
Specifics for KSTL: Current forecast is dry and given the latest
HRRR will leave it that way. At best it would be flurries that
would not impact visibility.IFR ceilings lifting around 12z and
VFR by 00z as the 850mb relative humidity drips off to 20%.
JPK
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 25 29 12 24 / 60 10 0 0
Quincy 17 20 5 18 / 80 10 0 0
Columbia 18 20 8 23 / 60 10 0 0
Jefferson City 19 23 8 25 / 60 10 0 0
Salem 31 34 13 23 / 20 20 0 0
Farmington 29 32 13 26 / 30 10 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
916 PM CST Sat Jan 3 2015
.UPDATE...
Issued at 916 PM CST SAT JAN 3 2015
Have issued a quick update to lower snow amounts south of I70 and
raise snow amounts across northern Missouri.
Water vapor with the 1.5 PVU pressure overlayed clearly shows the
strong shortwave over Kansas causing our weather mess locally.
Projecting this PV anomaly in time shows it lifting east-northward
right over the forecast area. This typically not a great scenario to
get deformation snowfall through the heart of the forecast area.
Rather, the drop in static stability associated with the PV anomaly
has lead to very "showery" type precip. This was likely enhanced by
the elevated instability from 00Z KTOP sounding showing ~160 J/kg for
a parcel lifted from above 700 mb. Earlier in the evening there was a
rapid transition from rain to snow in south central KS that to a
quick several inches of snow. This was associated with an area of
strong Fn convergence 750 to 700 mb layer along/north the developing
TROWAL as the system appeared to be peaking in intensity. The NAM
showed this area moving ENE but weakening as it did so and not really
being an issue. However, as the system matures, what looks like the
main deformation band is setting up over northern
Missouri/northeastern Kansas and corresponds to a newly strengthening
area of Fn convergence in the 700 to 650 mb layer along and just
north of the newly emerging TROWAL in the 300-305K layer. This shift
northward is supported by the latest HRRR and RUC as well as the
latest run of our local WRF-ARW.
The higher reflectivity returns showing up on radar in the last 30
minutes or so should continue to lift northward and feed into the
main deformation area to the north. Also, with the southeastern half
of the forecast area still above freezing, what has been snowing has
had an opportunity to accumulate as it melts on contact with the
warmer ground, cutting into accumulations further south.
So overnight snow amounts look like 1-2 inches in the northwestern half
of the forecast area with less than 1 inch amounts over the
southeastern half. Parts of the northern KC metro may still see 1-2
inches but lower amounts are expected further south.
&&
.SHORT TERM...(This Evening through Sunday Night)
Issued at 426 PM CST SAT JAN 3 2015
Tonight:
The second phase of the approaching winter system will quickly make
its presence felt over our CWA. The latest satellite and radar data
reveal the rapid development of the deformation zone precipitation
shield across south central and central KS. Satellite trends appear
to support the latest operational NAM, GFS and ECMWF which depict a
more southern track (vs yesterday`s solutions) of the main
precipitation. The HRRR and RUC also confirm this. So, with only
minor adjustments needed have shifted the axis of heavier snowfall
a bit further south.
Model output via Bufkit and the operational model snow algorithms
all point to a general 1-2 inch swath with isolated amounts to 3
inches possible from east central KS through west central MO. Snow
amounts will be limited by 1) initially falling as rain and 2)
melting at onset due to above freezing temperatures. An expected
quick transition to snow due to strong dynamic forcing within the
deformation cloud shield and the eventual surge of strong cold air
advection should mitigate this melting. Also of note is the
convective looking nature of the growing deformation cloud shield.
Close inspection of Bufkit data and model soundings suggest CSI may
be possible for a brief period early this evening with elevated CAPE
values approaching 100 J/kg. Evening shift will need to keep an eye
on this for possible thunder-snow and rapid increase in snow rates.
Strong cold air advection will rush from the Central Plains this
evening. Upstream obs show single digit temperatures and wind gust
of 35-40 mph. Thus blowing snow tied to the baroclinc zone snow
which will form across southeast NE this evening will be added to
the northern and western CWA. Have also allowed light snow/flurries
to linger well after midnight as ice crystals will be produced down
into the boundary layer as temperatures fall to -15C within the
saturated cloud layer between 2500-5000ft agl.
Due to the combo of 25-35 mph winds and single digit temperatures
have added a wind chill advisory for the northwest tip of MO.
Sunday and Sunday Night:
Brutally cold. That`s all you need to know. A 1041 mb surface high
will sit over KS and western MO during this period. A stiff
northwest wind will diminish from west to east in the morning and
clouds will clear so we`ll get some relief from the cold. However,
the weight of h8 temperatures of -10C to -15C will limit highs to
mainly the teens.
Some mid level warm advection clouds streaming in from NE may be the
saving grace for below zero temperatures Monday night. That plus
very light winds may only generate wind chills from -5 to -15F.
.LONG TERM...(Monday through Saturday)
Issued at 426 PM CST SAT JAN 3 2015
Looking ahead to the extended...everyone may want to keep those
heavy winter coats out a while longer. The forecast continues to
remain cold and mostly dry until late in the upcoming work week. An
upper level ridge will remain planted across the western US coast
with a very wide longwave trough over the remainder of the US. This
places the CWA in northwest flow aloft with a number of disturbances
translating through the main flow. Each of these systems will
provide a reinforcing shot of cold air into the region. With snow
remaining on the ground, airmass modification will be minimal
allowing morning lows to tumble into the low single digits with a
few negative single digits along the MO/IA border Monday morning.
While the EC and GFS 850mb temperatures are off a few degrees from
each other, they are still bringing in temperatures ranging from -17 to
-25 C over the CWA. Thus, it is likely that lows will plummet into
the negative singles Wed morning across the northern half of CWA,
and then low singles on either side of zero by Thurs morning. High
temperatures look to warm into the upper teens and into the low and
mid 20s much of the week, except Wed when it will be tough to climb
into the teens. Precip-wise, the northeast corner of the CWA may see
some light snow Mon night as one of the previously mentioned systems
glances the area. Long-range models are also indicating that the
region may see increasing chances for precip late in the week, but
given that it is towards the end of the extended a lot can, and
probably will, change over the next several days as the system
begins to evolve.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 527 PM CST SAT JAN 3 2015
Precipitation will soon work its way into the area, initially taking
on the form of light rain. This will quickly transition to a rain
snow mix between 07Z-08Z, then to all snow by 09Z as the boundary
layer cools to below freezing. Overall, expecting MVFR ceilings and
visibilities with a brief period of IFR conditions due to blowing
snow from 05Z- 08Z as winds pick up out of the northwest. Not
anticipating a long-duration event with the snow as this will move
east overnight. Ceilings and visibilities will gradually lift during
the morning hours, though gusty winds will persist until the early
afternoon.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY until 3 AM CST Sunday FOR KSZ025-057-
103>105.
WINTER WEATHER ADVISORY until 6 AM CST Sunday FOR KSZ102.
MO...WINTER WEATHER ADVISORY until 3 AM CST Sunday FOR MOZ013>017-
020>025-028>033-037>039-043-044.
WINTER WEATHER ADVISORY until 6 AM CST Sunday FOR MOZ001>008-011-
012.
WIND CHILL ADVISORY from 3 AM to 9 AM CST Sunday FOR MOZ001-002-
011.
&&
$$
UPDATE...CDB
SHORT TERM...MJ
LONG TERM...PMM
AVIATION...Welsh
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
538 PM CST Sat Jan 3 2015
.SHORT TERM...(This Evening through Sunday Night)
Issued at 426 PM CST SAT JAN 3 2015
Tonight:
The second phase of the approaching winter system will quickly make
its presence felt over our CWA. The latest satellite and radar data
reveal the rapid development of the deformation zone precipitation
shield across south central and central KS. Satellite trends appear
to support the latest operational NAM, GFS and ECMWF which depict a
more southern track (vs yesterday`s solutions) of the main
precipitation. The HRRR and RUC also confirm this. So, with only
minor adjustments needed have shifted the axis of heavier snowfall
a bit further south.
Model output via Bufkit and the operational model snow algorithms
all point to a general 1-2 inch swath with isolated amounts to 3
inches possible from east central KS through west central MO. Snow
amounts will be limited by 1) initially falling as rain and 2)
melting at onset due to above freezing temperatures. An expected
quick transition to snow due to strong dynamic forcing within the
deformation cloud shield and the eventual surge of strong cold air
advection should mitigate this melting. Also of note is the
convective looking nature of the growing deformation cloud shield.
Close inspection of Bufkit data and model soundings suggest CSI may
be possible for a brief period early this evening with elevated CAPE
values approaching 100 J/kg. Evening shift will need to keep an eye
on this for possible thunder-snow and rapid increase in snow rates.
Strong cold air advection will rush from the Central Plains this
evening. Upstream obs show single digit temperatures and wind gust
of 35-40 mph. Thus blowing snow tied to the baroclinc zone snow
which will form across southeast NE this evening will be added to
the northern and western CWA. Have also allowed light snow/flurries
to linger well after midnight as ice crystals will be produced down
into the boundary layer as temperatures fall to -15C within the
saturated cloud layer between 2500-5000ft agl.
Due to the combo of 25-35 mph winds and single digit temperatures
have added a wind chill advisory for the northwest tip of MO.
Sunday and Sunday Night:
Brutally cold. That`s all you need to know. A 1041 mb surface high
will sit over KS and western MO during this period. A stiff
northwest wind will diminish from west to east in the morning and
clouds will clear so we`ll get some relief from the cold. However,
the weight of h8 temperatures of -10C to -15C will limit highs to
mainly the teens.
Some mid level warm advection clouds streaming in from NE may be the
saving grace for below zero temperatures Monday night. That plus
very light winds may only generate wind chills from -5 to -15F.
.LONG TERM...(Monday through Saturday)
Issued at 426 PM CST SAT JAN 3 2015
Looking ahead to the extended...everyone may want to keep those
heavy winter coats out a while longer. The forecast continues to
remain cold and mostly dry until late in the upcoming work week. An
upper level ridge will remain planted across the western US coast
with a very wide longwave trough over the remainder of the US. This
places the CWA in northwest flow aloft with a number of disturbances
translating through the main flow. Each of these systems will
provide a reinforcing shot of cold air into the region. With snow
remaining on the ground, airmass modification will be minimal
allowing morning lows to tumble into the low single digits with a
few negative single digits along the MO/IA border Monday morning.
While the EC and GFS 850mb temperatures are off a few degrees from
each other, they are still bringing in temperatures ranging from -17 to
-25 C over the CWA. Thus, it is likely that lows will plummet into
the negative singles Wed morning across the northern half of CWA,
and then low singles on either side of zero by Thurs morning. High
temperatures look to warm into the upper teens and into the low and
mid 20s much of the week, except Wed when it will be tough to climb
into the teens. Precip-wise, the northeast corner of the CWA may see
some light snow Mon night as one of the previously mentioned systems
glances the area. Long-range models are also indicating that the
region may see increasing chances for precip late in the week, but
given that it is towards the end of the extended a lot can, and
probably will, change over the next several days as the system
begins to evolve.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 527 PM CST SAT JAN 3 2015
Precipitation will soon work its way into the area, initially taking
on the form of light rain. This will quickly transition to a rain
snow mix between 07Z-08Z, then to all snow by 09Z as the boundary
layer cools to below freezing. Overall, expecting MVFR ceilings and
visibilities with a brief period of IFR conditions due to blowing
snow from 05Z- 08Z as winds pick up out of the northwest. Not
anticipating a long-duration event with the snow as this will move
east overnight. Ceilings and visibilities will gradually lift during
the morning hours, though gusty winds will persist until the early
afternoon.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY until 3 AM CST Sunday FOR KSZ025-057-
103>105.
WINTER WEATHER ADVISORY until 6 AM CST Sunday FOR KSZ102.
MO...WINTER WEATHER ADVISORY until 3 AM CST Sunday FOR MOZ013>017-
020>025-028>033-037>039-043-044.
WINTER WEATHER ADVISORY until 6 AM CST Sunday FOR MOZ001>008-011-
012.
WIND CHILL ADVISORY from 3 AM to 9 AM CST Sunday FOR MOZ001-002-
011.
&&
$$
SHORT TERM...MJ
LONG TERM...PMM
AVIATION...Welsh
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
514 PM CST Sat Jan 3 2015
.SHORT TERM: (Through Sunday)
Issued at 339 AM CST Sat Jan 3 2015
Forecast on track with upper level low/shortwave moving northeast
across the region this evening. Precipitation associated with this
feature should start as rain and then transition to snow before
ending. Best chance of an inch of accumulation will be across the
far northern CWA. Otherwise, some mood snow showers or flurries
will be the rule as colder air pours into the region overnight
into Sunday morning. Sunday will be breezy and much colder with
temperatures continuing to slowly fall throughout the day.
.LONG TERM: (Monday through Next Saturday)
Issued at 230 PM CST Sat Jan 3 2015
Temperature will moderate some on Monday as a clipper system
tracks north of the area. Have kept the forecast dry based on the
consensus track of the system to our north.
Pattern really amplifies behind this clipper with a very strong
arctic high pressure system moving into the mid section of the
country for midweek. This will be the coldest air we have seen this
winter season. Expect temperatures to be at 20 to 30 degrees below
normal Tuesday night through Thursday. As previous forecaster
stated, below zero temperatures are likely for a large portion of
the area Thursday morning as the center of the anticyclone will be
parked over head. The latest MEX guidance has below zero
temperatures at STL both Wednesday and Thursday morning - WITH NO
SNOW COVER. Have trended the forecast colder based on the latest
model data and expect wind chill values will warrent advisories to
be issued in the future.
Airmass really struggles to moderate before the next storm system
moves toward the area late next week and weekend. This could set the
stage for a more widespread winter weather event across the CWA
Friday night/Saturday morning. For now will keep chance POPs for
snow as the ECWMF does not depict as deep/strong of a
shortwave/surface reflection at this time.
CVKING
&&
.AVIATION: (For the 00z TAFs through 00z Sunday Evening)
Issued at 453 PM CST Sat Jan 3 2015
Closed upper low over north central Oklahoma opening as it lifts
northeast. Current models reflect this in the precipitation
forecast with the precipitation diminishing as it lifts northeast.
The latest HRRR is also not bullish on the precipitation with most
of it gone by 07z. A period of light snow is certainly possible
for COU and UIN with a 03z to 07z for COU and and hour later for
UIN. Northwest wind picks up from 06z to 12z west to east as the
surfact low moves northeast out of the area. IFR ceilings should
lift to MVFR as the wind picks up with VFR beginning to show up
after 20z.
Specifics for KSTL: Current forecast is dry and given the latest
HRRR will leave it that way. At best it would be flurries that
would not impact visibility.IFR ceilings lifting around 12z and
VFR by 00z as the 850mb relative humidity drips off to 20%.
JPK
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 25 28 12 24 / 40 10 0 0
Quincy 17 19 5 18 / 80 10 0 0
Columbia 18 20 8 23 / 70 10 0 0
Jefferson City 19 21 8 25 / 60 10 0 0
Salem 31 34 13 23 / 20 20 0 0
Farmington 29 32 13 26 / 20 10 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1144 PM CST Thu Jan 1 2015
.UPDATE:
Issued at 1005 PM CST Thu Jan 1 2015
Activity picking up a bit on radar as of 04z. Fairly light, in the
form of light rain and some sleet being reported. With further
north placement, upped pops to slight chance as far north as I-70
through the early morning hours of Friday.
Byrd
&&
.SHORT TERM: (Tonight and Friday)
Issued at 338 PM CST Thu Jan 1 2015
The area is sandwiched between high pressure to the south and a trof
of low pressure up across the Upper Midwest. Southwest flow is the
result and temperatures have rebounded into the mid and upper 30s
across the entire area. With abundant cloud cover and weak
southwest flow continuing tonight, expect that lows tonight will be
several degrees warmer tonight than they were last night. Most
areas should get back down below freezing again, but think temps
should stay mostly in the upper 20s to low 30s across the majority
of the area (with the exception of northern MO and west central IL
where clouds should be thinner allowing for more radiational
cooling). NAM, GFS, and RAP develop some weak moisture convergence
on the 850mb baroclinic zone Friday morning just south of the STL
Metro area. While the GFS says dry, the NAM and to a lesser extent
the RAP do print out a little very light QPF. 4km NCEP and NSSL WRF
models also show very light QPF Friday morning, and light simulated
radar returns as well. Therefore, feel there`s enough signal to
bump up PoPs slightly for Friday morning along and southeast of
I-44/US-50. P-types will likely start out as a little rain/sleet
mix and where temps are below freezing there could be a bit of
glaze, but amounts look very light. Precip should turn quickly to
light rain or just sprinkles with a couple of hours of sunrise, and
highs look to be in the mid to upper 30s across the area on Friday.
Carney
.LONG TERM: (Friday Night through Next Thursday)
Issued at 421 PM CST Thu Jan 1 2015
Models are coming into better consensus with the storm system for
Friday night and Saturday. GFS and NAM continue to warm up bit by
bit. Most recent partial thickness forecasts show all critical
thickness lines for rain/snow well up into northern
Missouri/southern Iowa by the time the precipitation starts on
Friday night. Forecast soundings also have little or no cold layer
in the low levels indicating that sleet is becoming less and less
likely. So have more or less confined any chances of sleet to
northern zones Friday evening, changing over to all rain and
freezing rain where surface temperatures dictate. Think any
accumulations of freezing rain will be minor due to warm ground
temperatures and diabatic warming due to latent heat release.
Temperatures should warm above freezing after sunrise on Saturday
morning at any rate which should stop any ice accumulation. Think
the greatest amount of accumulation will be over northern MO and
west central IL and amounts should be between a trace and 0.05 inch.
Dry slot should wrap around into the storm on Saturday afternoon
which will likely make the rain slack off and even end across
southern portions of the area. Cold front moves through Saturday
evening with the tail end of the def-zone clipping our area.
Guidance seems to want to keep the majority of the QPF out of our
area over northwest Missouri and southern Iowa. However, it looks
like our northwest counties could get clipped with an inch or two of
snow before all the shouting is over.
Remainder of the forecast looks cold and dry as a longwave trof
deepens over the eastern CONUS. This will allow a couple of Arctic
air intrusions into the lower 48...one on Sunday and Monday behind
the weekend storm, and another midweek. This should keep
temperatures well below normal through the end of the forecast
period.
Carney
&&
.AVIATION: (For the 06z TAFs through 06z Friday Night)
Issued at 1134 PM CST Thu Jan 1 2015
Patchy light rain mixed at times with light sleet will impact the
St. Louis area terminals through 07-08z, otherwise VFR flight
conditions expected overnight. Still anticipating MVFR cigs moving
into KCOU and the St. Louis terminals around daybreak and gradually
lowering cigs during the afternoon. Main thrust of precipitation
in the form of rain should begin on Friday evening and have
introduced some PROB30 groups for initial estimate of the onset
timing. IFR flight conditions and nearly continuous rainfall
expected to evolve after 06z Saturday.
Specifics for KSTL:
Patchy light rain mixed at times with light sleet will be possible
through around 07z, otherwise VFR flight conditions expected
overnight. Still anticipating MVFR cigs moving into KSTL near daybreak
and gradually lowering cigs during the afternoon. Main thrust of
precipitation in the form of rain should begin on Friday evening
and have introduced a PROB30 group for initial estimate of the
onset timing at 03z. IFR flight conditions and nearly continuous
rainfall expected to evolve after 06z Saturday.
Glass
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
103 AM EST FRI JAN 2 2015
.SYNOPSIS...
ACCUMULATING LAKE EFFECT SNOW WILL OCCUR TO THE SOUTHEAST OF LAKE
ONTARIO THROUGH FRIDAY NIGHT. A MORE WIDESPREAD STORM SYSTEM IS
EXPECTED TO BRING A MIX OF SNOW...SLEET AND FREEZING RAIN INTO THE
AREA BY LATE SATURDAY AFTERNOON. THE WINTRY MIX WILL THEN CHANGE
TO RAIN DURING THE NIGHT...FOLLOWED BY WARMER TEMPERATURES AND
SHOWERS ON SUNDAY.
&&
.NEAR TERM /THROUGH TODAY/...
10 PM UPDATE...
SOUTHERN PERIPHERY OF LAKE ONTARIO SNOW BAND IS JUST NOW TOUCHING
THE FAR NORTHERN BORDER OF ONEIDA COUNTY. BASED ON WINDS OFF THE
LAKE AND LATEST MESO MODEL OUTPUT, BELIEVE THE BAND WILL DROP INTO
OUR FA IN THE NEXT 2 TO 3 HOURS. SNOWFALL INTENSITIES COULD REACH
1 TO 2 INCHES PER HOUR BETWEEN 6Z AND 12Z.
THE SYR BUFKIT PROFILE OFF THE 18Z NAM SUGGESTS THE BAND WILL DROP
SOUTH TO I-90 LATE TOMORROW MORNING OR EARLY AFTERNOON. WILL NEED
TO WATCH IF THE BAND CAN MAKE IT DOWN INTO THE CITY. IT WILL BE A
VERY CLOSE CALL REGARDLESS.
RAISED MINS FOR MOST LOCALES OVERNIGHT. SOUTHWESTERLY FLOW THIS
EVENING HAS HELD TEMPS NEAR 30 DEGREES IN MANY SPOTS. USED A
COMBINATION OF LAMP AND RAP HOURLY GUIDANCE FOR OVERNIGHT TEMPS.
3 PM UPDATE...
LOWER CLDS EXPECTED ALONG NRN ZONES AS MOISTURE CONTS TO STREAM
OFF OF UPSTREAM LKS IN SW FLOW. MAJORITY OF CWA SEEING FILTERED
SUNSHINE THRU HIGH CIRRUS. SFC LOW LOCATED NR HUDSON BAY AND CDFNT
EXTNDG BACK TO THE SW THRU LK SUPERIOR WL SHIFT SOUTH TONIGHT.
ADDED LIFT ALONG FRONT COMBINED WITH LK MOISTURE WL SET THE STAGE
FOR SIGNIFICANT LK SNOWS FOR LATE TONIGHT AND FRIDAY.
SNOWS WL BEGIN TO DROP INTO EXTRM NRN ONEIDA CNTY ARND MIDNIGHT
TONIGHT WITH DEEP INVERSION BCMG ESTABLISHED DRG THE MID-MRNG HRS.
INVERSION LOOKS TO BE ABOUT 7KFT DEEP WITH WELL-ALIGNED FLOW AND
QUITE A BIT OF INSTABILITY. AS THE CDFNT SHIFTS SOUTH AFT DAYBREAK
WINDS WL ALIGN FM A 280-290 FLOW AND RESULT IN SINGLE BAND OF SNOW.
LOOKS AS THO GEORGIAN BAY CONNECTION WL BE ESTABLISHED DRG THE LATE
MRNG/AFTN HRS. BAND LOOKS TO BE FAIRLY STEADY-STATE BTWN 15Z-21Z THO
IT WL BE WOBBLING A BIT. THUS EXPECT MAX SNOWFALL RATES OF 1-2
INCHES PER HR DRG THE LATE MRNG HRS AND POSSIBLY INTO THE AFTN.
AS DIURNAL HTG BEGINS TO WORK IT`S MAGIC EXPECT THAT SINGLE BAND WL
GO MORE CELLULAR DRG THE AFTN AND INTENSITY WL GRADUALLY BEGIN TO
LESSEN. STORM TOTAL SNOW ACCUMS FM 03Z TONIGHT TO 00Z SAT WL RANGE
FM 5-8 INCHES NORTH OF THE NY THRUWAY. EXCEPTION WL BE EXTRM NW
ONEIDA CNTY WHERE UP TO ONE FOOT OF SNOW IS EXPECTED TO FALL. THUS
HV GONE WITH LES WARNING FOR NRN ONEIDA AND LES ADVISORY FOR
ONONDAGA, MADISON AND SRN ONEIDA CNTYS FM 03Z TONIGHT TO 00Z SAT.
SNOWS WL SLIDE NORTH ON FRI NGT AND CONTRACT BACK TWD THE SHORE LINE
WITH JUST SCTD SNOW SHOWERS AS WINDS BACK ARND TO THE SW. 1035MB SFC
HIGH WL SETTLE ACRS SRN QUEBEC FRI NGT WITH RIDGE AXIS EXTNDG SWRD
INTO CWA ASSURING A QUIET NIGHT WHILE WE WAIT FOR THE NEXT SYSTEM.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
GLOBAL AND REGIONAL COMPUTER MODELS FROM AROUND THE WORLD REMAIN
CONSISTENT WITH A LOW PRESSURE AREA LIFTING OUT OF THE SOUTHERN
PLAINS EARLY THIS WEEKEND...AND TRACKING THROUGH THE GREAT LAKES
AND EASTERN CANADIAN PROVINCES ON SUNDAY. THE OVERALL PATTERN
RECOGNITION OF THIS SYSTEM SUGGESTS A RAPIDLY TRANSITIONING WINTRY
MIX EVOLVING OVER CNY AND NEPA FROM SATURDAY AFTERNOON TO EARLY
SUNDAY MORNING. AT THIS STAGE OF THE GAME...THE BEST SOLUTION IS
TO STILL BLEND THE VARIOUS GUIDANCE PACKAGES TO DETERMINE THE
THERMAL PROFILES AND RESULTING TIMING OF THE VARIOUS PRECIP TYPES.
MOST OF THE FIELDS ARE WITHIN A DEGREE OR TWO...BUT IT WAS NOTED
THAT THE NAM WAS SUGGESTING SLIGHTLY COLDER SFC VALUES AND WARMER
THICKNESS PATTERNS ALOFT AS THE PRECIP MOVES IN. OTHERWISE...THE
DETAILED SOUNDING PROFILES INDICATE THE WARM LAYERS TO BE FAIRLY
HIGH IN THE ATMOSPHERE WITH A SUBSTANTIAL (4-5 KFT) DEPTH OF SUB
FREEZING AIR TO THE SURFACE. THIS ACTUALLY SUGGESTS THERE COULD BE
A FAIR AMOUNT OF SLEET GOING ON WITH THE SNOW AND BETWEEN THE
CHANGE TO FRZG RAIN AND RAIN. ISENTROPIC LIFT SHOULD ALLOW PRECIP
TO BREAK OUT A LITTLE SOONER THAN WHAT THE GFS/ECMWF HAD
PREVIOUSLY ADVERTISED. THE NAM WAS THE FASTEST WITH ONSET...BUT
NOW LOOKS LIKE THE 12Z GFS HAS CAUGHT UP...SO THERE WILL BE
ADJUSTMENTS TO CATEGORICAL/LIKELY POPS BY A FEW HOURS TO INDICATE
PRECIP COMING DOWN IN THE AREA BY DARK. AMOUNTS OF ANY ONE P-TYPE
LOOK TO BE LIMITED GIVEN WHAT IS EXPECTED TO BE ONLY A SHORT
AMOUNT OF RESIDENT TIME FOR THE PHASE CHANGES. MOST AREAS SHOULD
SEE ONLY A COUPLE INCHES OR LESS OF SNOW/SLEET...AND A GLAZE OF
ICE ACCRETION. WARM AIR ALOFT QUICKLY EXCEEDS 3 DEG CELSIUS WHICH
CAN INDICATE THE RAIN IS WARM AND WILL HAVE DIFFICULTY ACCRETING
ON SURFACES. STILL...A FZRA EVENT IS NOTHING TO SNEEZE AT AND
PREPARATIONS TO MITIGATE THE TRAVEL HAZARD SHOULD BE PLANNED FOR
THIS WEEKEND.
BEHIND THIS SYSTEM...A SHORT...MILD SPELL IS EXPECTED IN A NARROW
WARM SECTOR ON SUNDAY WITH A FEW RAIN SHOWERS AS THE SYSTEM DRY
SLOT PUSHES OVERHEAD. THEN...A RETURN TO THE ARCTIC AIR IS LIKELY
AND THE PATTERN SUGGESTS THERE COULD BE ANOTHER ROUND OF
SIGNIFICANT LAKE EFFECT POURING OFF THE EASTERN AND SOUTHEASTERN
SHORES OF LAKE ONTARIO AND INTO THE SYRACUSE-ROME-UTICA AREAS FROM
SUNDAY NIGHT THROUGH MONDAY NIGHT. WE HAVE FAIRLY GOOD CONFIDENCE
IN THIS EVENT OCCURRING...AND HAVE BUMPED UP POPS IN THE LAKE BELT
ZONES DURING THAT TIME.
NORTHWEST WINDS SHOULD ALSO BEGIN CRANKING UP WITHIN THE COLD
ADVECTIVE AND UNSTABLE REGIME...WITH A POTENTIAL FOR SUSTAINED
WIND SPEEDS IN THE 15-25 MPH WITH GUSTS INTO THE 30S FROM SUN
NIGHT INTO MONDAY.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
LAKE EFFECT EVENT WILL PROBABLY BE ONGOING AT THE BEGINNING OF
THIS PERIOD...ONLY TO BE INTERRUPTED BY A PASSING UPPER WAVE AND
CLIPPER TYPE SURFACE LOW ON TUESDAY AS INDICATED BY BOTH ECMWF AND
GFS. THIS WILL LIKELY MEAN A CHANCE FOR WIDESPREAD LIGHT SNOW OF A
FEW INCHES. EVEN COLDER AIR USHERS IN ON THE BACKSIDE OF THAT LOW
WITH A CONTINUATION OF BROAD CYCLONIC FLOW ALOFT OVER THE AREA. A
STRONG 1040-1045 MB HIGH TO OUR WEST AND COLD NORTHWEST BOUNDARY
LAYER FLOW WILL ONCE AGAIN REKINDLE THE LAKE EFFECT SNOWS AND
UPSLOPE INSTABILITY SNOW SHOWERS THROUGH NEXT THURSDAY.
GENERALLY FOLLOWED THE WPC GUIDANCE GRIDS WITH MINOR ADJUSTMENTS
TO POPS FOR LAKE EFFECT.
COLDER THAN NORMAL ALL NEXT WEEK AND UNSETTLED SEEMS TO BE THE
OVERALL THEME.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
06Z UPDATE...
PASSAGE OF A SURFACE TROUGH IS IN THE PROCESS OF REDIRECTING LAKE
EFFECT SNOW TO KSYR-KRME CORRIDOR. MINOR RESTRICTIONS ARE
ONGOING...WITH FURTHER DEGRADATION TO FUEL ALT REQ MVFR CIG AND IFR
VIS FIGURED FOR 10Z-14Z TIME PERIOD KRME...AND AT LEAST 11Z- 15Z
FOR KSYR AS THE LAKE EFFECT BAND SHIFTS OVER THOSE TERMINALS. BAND
LOOKS LIKELY TO SET UP NEAR KSYR FOR A FAIR CHUNK OF THE DAY EVEN
AFTER 15Z...WHILE BEING MAINLY SOUTH OF KRME /THOUGH STILL MVFR/
BEFORE REVISITING WHILE SHIFTING NORTH THIS EVENING. SOME
UNCERTAINTY ON DURATION OF THAT SINCE INLAND EXTENT OF LAKE EFFECT
WILL BE DECREASING WITH TIME THIS EVENING. FOR KELM-KITH-
KBGM...IN-AND-OUT OF MVFR CONDITIONS AS LAKE ERIE CLOUDS WILL BE
PRESENT THROUGH MOST OF THE TAF PERIOD...WITH OCCASIONAL FLURRIES.
KAVP VFR WHOLE PERIOD. CURRENT WSW TO W WINDS 9-12 KTS WILL VEER
WITH TROUGH PASSAGE TO WNW DURING THE DAY...WITH GUSTS AROUND 20
KTS...BEFORE DIMINISHING LATE AFTERNOON-EVENING.
OUTLOOK...
SAT/SAT NGT...BECOMING IFR WITH SNOW DEVELOPING, CHANGING TO
WINTRY MIX AND OCNL RAIN/FRZG RAIN OVERNIGHT.
SUN...MAINLY VFR. SCT RAIN SHOWERS.
MON-TUE...SCT SNOW SHOWERS AND MINOR RESTRICTIONS...BUT MORE
SIGNIFICANT RESTRICTIONS POSSIBLE KSYR-KRME FROM LAKE EFFECT SNOW.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ018-036-037.
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST THIS EVENING FOR
NYZ009.
&&
$$
SYNOPSIS...PVF
NEAR TERM...DJP/PVF
SHORT TERM...JAB
LONG TERM...JAB
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1245 AM EST FRI JAN 2 2015
.SYNOPSIS...HIGH PRESSURE WILL EXTEND OVER THE ARE TODAY. A WARM
FRONT OVER THE GULF COAST WILL MOVE NORTHWARD INTO THE REGION LATE
TODAY THROUGH SATURDAY... AS ASSOCIATED LOW PRESSURE TRACKS FROM THE
DEEP SOUTH NORTHWARD TO THE GREAT LAKES. A COLD FRONT WILL CROSS THE
CAROLINAS FROM THE WEST ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 906 PM THURSDAY...
THE LATEST SATELLITE DATA INDICATED A RAPID INCREASE IN CLOUDINESS
AT SEVERAL LEVELS FROM THE WEST THIS EVENING. GIVEN THE EXTENSIVE
CLOUDINESS AND MOISTURE UPSTREAM ESPECIALLY IN THE MID AND HIGH
LEVELS... THE SKIES OVERNIGHT WILL BE MOSTLY CLOUDY TO CLOUDY. THERE
MAY BE A FEW THIN SPOTS OR BREAKS IN THE OVERCAST BUT THE CLOUDINESS
COMBINED WITH THE LIGHT SW FLOW AT 5-10 MPH SHOULD KEEP TEMPERATURES
IN CHECK. READINGS AT MID EVENING RANGED IN THE LOWER TO MID 40S
EXCEPT FOR SOME UPPER 30S WHERE THE CLOUDS WERE YET TO THICKEN UP.
TEMPERATURES SHOULD ONLY FALL OFF ABOUT 5 MORE DEGREES OR SO THEN
LEVEL OFF AS THE CLOUDS THICKEN. LOWS IN THE MID 30S TO NEAR 40
EXPECTED.
AS FOR THE PRECIPITATION CHANCES... RADAR INDICATED PATCHY LIGHT
RAIN ALREADY SPREADING GEORGIA AND MUCH OF TENNESSEE. HOWEVER...
THERE CONTINUED TO BE QUITE A BIT OF DRY AIR TO OVERCOME FROM THE
BOUNDARY LAYER THROUGH H7. MOST OF THE PRECIPITATION IS EXPECTED TO
FALL AS VIRGA THROUGH AT LEAST 12Z GIVEN THE AMOUNT OF DRY AIR TO
MOISTEN UP. THE HRRR INDICATED SOME LIGHT QPF (POSSIBLY 0.01 OR SO)
ACROSS THE SOUTH LATE.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 320 PM THURSDAY...
THE CLOSED LOW CENTERED NEAR THE FOUR CORNERS REGION EARLY FRIDAY
WILL SHIFT EAST REACHING THE TEXAS PANHANDLE BY SATURDAY MORNING. AT
THE SAME TIME...SURFACE HIGH PRESSURE DEVELOPS OVER THE NORTHEAST IN
RESPONSE TO THE STRONG CONVERGENT FLOW ALOFT. THIS AREA OF HIGH
PRESSURE RIDGES INTO THE CAROLINAS BY EARLY SATURDAY
MORNING...SETTING THE STAGE FOR ANOTHER COLD AIR DAMMING EVENT OVER
THE WEEKEND. PRECIPITATION IS LIKELY TO BE PRETTY SPOTTY ON FRIDAY
MORNING GIVEN THE WEAK FORCING FOR ASCENT AND LARGELY FOCUSED TO THE
WEST AND SOUTH OF GREENSBORO AND SANFORD. AS DEEP LAYER ISENTROPIC
LIFT INCREASES LATE FRIDAY AND FRIDAY NIGHT...EXPECT PRECIPITATION
IN THE FORM OF RAIN TO OVERSPREAD AND EXPAND ACROSS CENTRAL NC. THIS
WILL SUPPORT CHANCE POPS FRIDAY EVENING INCREASING TO LIKELY
OVERNIGHT. A COOL AIR MASS AND WIDESPREAD CLOUDINESS SHOULD KEEP
TEMPERATURES IN THE 50 TO 55 RANGE ON FRIDAY. LOWS FRIDAY NIGHT WILL
FALL INTO THE UPPER 30S TO LOWER 40S. -BLAES &&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 220 PM THURSDAY...
SATURDAY THROUGH SUNDAY NIGHT: THE UPPER LEVEL LOW OVER THE TX
PANHANDLE REGION EARLY SATURDAY WILL MIGRATE NNE INTO THE MID WEST
WHERE IT WILL MERGE WITH THE NORTHERN STREAM TROUGH BY LATE
SATURDAY. THE LOW WILL THEN BECOME MORE OF A SHORTWAVE SLIDING NE
ALONG THE EASTERN PERIPHERY OF THE TROUGH THROUGH THE GREAT LAKES AND
INTO NE CANADA BY SUNDAY NIGHT. THE MAIN TROUGH WILL LINGER OVER THE
MIDWEST ON SUNDAY...PUSHING INTO THE CAROLINAS AND FLATTENING OUT BY
MONDAY AFTERNOON. AT THE SURFACE...HIGH PRESSURE CENTERED OVER THE
NE ON SATURDAY WILL RIDGE SW INTO WESTERN NC...SETTING UP A COLD AIR
WEDGE OVER THE NW PIEDMONT. ALSO ON SATURDAY...A LOW WILL DEVELOP
OVER THE TX GULF COAST AND MOVE NNE INTO THE MID WEST AND THROUGH
THE GREAT LAKES BY SUNDAY EVENING...TRAILING A COLD FRONT BEHIND IT.
AS THE SURFACE LOW BEGINS IT TREK NNE...A WARM FRONT WILL BEGIN
LIFTING NORTHWARD THROUGH NC WHERE IT WILL IMPINGE UPON THE WEDGE
BOUNDARY. THE WEDGE WILL LIKELY REMAIN OVER THE NW PIEDMONT THROUGH
SATURDAY NIGHT...BREAKING ON SUNDAY...ALLOWING THE WARM FRONT TO
LIFT THROUGH THE REST OF CENTRAL NC FOR A BRIEF PERIOD BEFORE THE
COLD FRONTAL PASSAGE SUNDAY NIGHT. THE WARM MOIST ADVECTION AHEAD OF
THE COLD FRONT WILL BE STRONG...WHICH WILL RESULT IN TEMPS WELL
ABOVE NORMAL...ESPECIALLY IN THE SE SOUTH OF THE WARM FRONT.
HOWEVER...GIVEN THE UNCERTAINTY OF WHEN AND IF THE WEDGE WILL BREAK
AHEAD OF THE COLD FRONT...CONFIDENCE IN THE TEMPERATURES FOR SUNDAY
AND SUNDAY NIGHT IS STILL RELATIVELY LOW. THE MODELS INDICATE A FEW
HUNDRED JOULES OF CAPE ON SUNDAY AHEAD OF THE FRONT...THUS HAVE GONE
AHEAD AND ADDED A SLIGHT CHANCE FOR THUNDER INTO THE FORECAST FOR
SUNDAY AFTERNOON THROUGH APPROX MIDNIGHT. THE MODELS ARE IN BETTER
AGREEMENT WITH THE TIMING OF THE COLD FRONT...WHICH WILL PUSH
THROUGH THE ENTIRE AREA BY 12Z MONDAY. KEEPING IN MIND THE LOW
CONFIDENCE IN TEMPS MENTIONED ABOVE...EXPECT HIGHS AND LOWS SATURDAY
AND SATURDAY NIGHT GENERALLY IN THE MID 40S NW TO MID 50S. THE
TEMPERATURES SHOULD GRADUALLY RISE OVERNIGHT SATURDAY TO UPPER 40S
NW TO LOW 60S SE BY 12Z SUNDAY...INCREASING FURTHER TO HIGHS AROUND
60 DEGREES NW TO AROUND 70 DEGREES SE ON SUNDAY. LOWS SUNDAY NIGHT
MAINLY IN THE MID 30S NW TO LOW 40S SE.
MONDAY THROUGH THURSDAY: EXPECT GENERALLY FAIR/DRY WEATHER TO RETURN
ON MONDAY BEHIND THE COLD FRONT...WITH AN ARCTIC HIGH RIDGING INTO
THE AREA AS THE CENTER OF THE HIGH MOVE EAST THROUGH THE VIRGINIAS.
EXPECT BELOW NORMAL TEMPERATURES GRADUALLY DECREASING FROM MONDAY...
MID 40S NW TO LOW 50S SE...TO THURSDAY...UPPER 30S NORTH TO AROUND
40 DEGREES SOUTH.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 1245 AM FRIDAY...
PRIMARY AVIATION CONCERN: A TREND TOWARD MVFR CIGS FROM SW TO NE
STARTING LATE THIS AFTERNOON.
LOW PRESSURE DEVELOPING JUST OFF THE TX GULF COAST HAS A WARM FRONT
EXTENDING EASTWARD ALONG THE GULF COAST. THIS LOW WILL STRENGTHEN
AND TRACK NE THROUGH THE LOWER MISS VALLEY TOWARD MICH TODAY AND
TONIGHT... AS THE WARM FRONT TRACKS NORTHWARD TOWARD NC. VFR CLOUDS
WILL CONTINUE TO SPREAD IN FROM THE WEST AND STEADILY THICKEN AND
LOWER OVER CENTRAL NC THROUGH TODAY... BUT CIGS ARE EXPECTED TO
REMAIN VFR THROUGH AT LEAST 20Z. CIGS SHOULD THEN SLOWLY LOWER TO
MVFR BETWEEN 21Z AND 00Z... FIRST AFFECTING INT/GSO/FAY THEN
RDU/RWI. MVFR CIGS SHOULD THEN DOMINATE AT ALL SITES AFTER 00Z
THROUGH THE END OF THE TAF VALID PERIOD... WITH PATCHY LIGHT RAIN
MOVING IN... ALTHOUGH VFR VSBYS SHOULD REMAIN DOMINANT INITIALLY.
WINDS WILL STAY LIGHT AND VARIABLE WITH SPEEDS MAINLY UNDER 5 KTS...
BECOMING PREDOMINANTLY FROM THE ENE AFTER 00Z.
LOOKING BEYOND 06Z EARLY SAT MORNING... HIGH CONFIDENCE THAT CIGS
WILL CONTINUE TO TREND DOWNWARD... TO IFR/LIFR OVERNIGHT AT ALL
SITES WITH RAIN BECOMING MORE WIDESPREAD YIELDING SUB-VFR VSBYS.
STARTING BY DAYBREAK SAT AND CONTINUING SAT THROUGH SAT NIGHT...
EXPECT IFR/LIFR CIGS AND MVFR/IFR VSBYS WITH PERIODS OF LIGHT RAIN
AND DRIZZLE AT ALL SITES. THE CRITERIA OF LOW LEVEL WIND SHEAR ARE
UNLIKELY TO BE MET INITIALLY... ALTHOUGH WE WILL STILL SEE
STRENGTHENING AND VEERING WINDS WITH HEIGHT LATE TONIGHT THROUGH
SAT. BY SUNSET SAT THE CHANCE OF LLWS WILL INCREASE AND REMAIN HIGH
THROUGH SAT NIGHT... UNTIL THE WARM FRONT TRACKS TO THE N OR NW
THROUGH THE AREA. SUB-VFR CIGS WILL HOLD INTO SUN... WITH A GOOD
CHANCE OF SHOWERS AND FEW STORMS AHEAD OF A COLD FRONT THAT WILL
SWEEP EAST THROUGH THE AREA SUN AFTERNOON/EVENING. VFR CONDITIONS
WILL RESUME POST-FRONT SUN NIGHT THROUGH TUE AS HIGH PRESSURE BUILDS
INTO THE AREA. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...BADGETT
SHORT TERM...BLAES
LONG TERM...KC
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
922 PM EST SAT JAN 3 2015
.SYNOPSIS...
LOW PRESSURE OVER NORTHWEST OHIO WILL CONTINUE NORTHEAST AND
CROSS THE EASTERN GREAT LAKES TONIGHT. A COLD FRONT TRAILING THE
LOW WILL SWEEP ACROSS THE AREA LATE TONIGHT AND EARLY SUNDAY.
ARCTIC HIGH PRESSURE WILL BUILD EAST ON MONDAY. A CLIPPER LOW
PRESSURE SYSTEM WILL CROSS THE AREA ON TUESDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
TRICKY FORECAST TONIGHT WITH TEMPS THE MAIN CHALLENGE. READINGS
HAVE CLIMBED IN THE MID 50S ALONG THE I-71 CORRIDOR BUT REMAIN IN
THE MID 30S OVER NW OHIO. TEMPS PROBABLY WILL REMAIN ABOUT WHERE
THEY ARE THE REMAINDER OF THE NIGHT AND HAVE TRIED TO WORD THE NEW
FORECAST ACCORDINGLY. THE LASTEST HRRR AND RUC CONTINUE TO SHOW
ANOTHER WAVE OF PRECIP MOVING ACROSS THE AREA OVERNIGHT. MOST OF
THIS SHOULD BE OVER THE EASTERN TWO THIRDS OF THE AREA.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
SUNDAY WILL BEGIN WITH A CHANCE OF RAIN WITH RAIN CHANGING TO SNOW
FROM WEST TO EAST AS COLDER AIR MOVES IN BEHIND THE FRONT. 12Z
850MB TEMPS STILL POSITIVE ACROSS OHIO BUT BY 18Z -4C LINE GETS TO
KCLE WITH -6C AT KTOL. BEST WRAP AROUND MOISTURE GETS INTO THE
AREA DURING THE AFTERNOON POST DRY SLOT. WILL HAVE CHANCE POPS FOR
MOST OF THE AREA THROUGH THE MORNING AND THEN BOOST TO LIKELY WEST
HALF FOR THE AFTERNOON...TRANSITIONING THE LIKELY POPS TO
NORTHEAST OHIO AND NWRN PA FOR THE EVENING AS DRIER AIR MOVES IN
FROM THE WEST. AT THIS TIME NOT EXPECTING A LOT OF SNOW AND WILL
HAVE LESS THAN AN INCH. OVERNIGHT SUNDAY NIGHT WILL CONTINUE WITH
LIKELY POPS ACROSS THE SNOWBELT WITH ABOUT 3 INCHES OR SO FOR
ACCUMS. MONDAY ARCTIC HIGH PRESSURE BUILDS IN FROM THE NORTHWEST.
THE AIRMASS DRYS OUT SIGNIFICANTLY. WILL HAVE DRY BUT UNPLEASANTLY
COLD CONDITIONS FOR MOST THE AREA. EXCEPTION BEING THE SNOWBELT.
WITH THE FORECAST KERI SOUNDING SHOWING MODERATE INSTABILITY WITH
THE LAKE AM EXPECTING LAKE EFFECT TO CONTINUE THROUGH THE DAY.
INVERSION IS NOT VERY HIGH AT AROUND 5KFT BUT SNOW GROWTH TEMPS
ARE FAVORABLY POSITIONED WITHIN THE UPDRAFTS WITH VERY LITTLE SHEAR
OR TURNING OF THE WIND. FOR NOW GIVEN THE DRY AIR WILL LIMIT
ACCUMS TO AN INCH OR TWO BUT WILL NEED TO CONTINUE TO WATCH.
OTHERWISE MONDAY MORNING TEMPS/WINDS MAY REQUIRE A WIND CHILL
ADVISORY AS APPARENT TEMPS GET TO AROUND 7 BELOW ZERO NWRN OHIO.
NEXT BIG ISSUE WILL BE THE CLIPPER THAT TRACKS ACROSS THE AREA
MONDAY NIGHT AND TUESDAY. SEE A GOOD 3 TO 5 INCH ACCUM IF IT
REMAINS ON TRACK. AGAIN TIME WILL TELL BUT FOR NOW DID BRING IN 2
TO 4 INCHES WEST HALF FOR LATE MONDAY NIGHT WITH SIMILAR AMOUNTS
EAST BEGINNING LATE MONDAY NIGHT THROUGH TUESDAY.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
COLD AIR WILL BE SURGING SOUTHWARD IN THE WAKE OF A MORNING COLD
FRONT ON WEDNESDAY. MAY HAVE LITTLE OR NO RISE IN TEMPERATURES IF
THIS TIMING HOLDS. WE ARE TALKING SINGLE DIGIT/LOW TEENS
HIGHS...LOWS ON EITHER SIDE OF ZERO...AND WIND CHILLS BELOW ZERO.
THIS FRONT WILL ALSO BRING WITH IT A LITTLE LIGHT SNOW FOR MOST
WEDNESDAY AND LAKE EFFECT FOR THE SNOWBELT GOING INTO AND THROUGH
THURSDAY. HIGH PRESSURE FROM THE NORTHERN PLAINS WILL HAVE SHIFTED
SOUTHEAST TO THE LOWER OHIO AND TN VALLEYS BY THURSDAY NIGHT
BRINGING THE FLOW AROUND TO THE SOUTHWEST. WITH THE COLD AIR
ENCOMPASSING EVERYWHERE EAST OF THE ROCKIES THE WARM AIR
ADVECTION/AIRMASS MODIFICATION LATER IN THE WEEK WILL ONLY BRING
TEMPERATURES SLOWLY UP THROUGH THE UPPER TEENS THURSDAY AND TO THE
LOWER 20S FOR FRIDAY AND SATURDAY.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
SURFACE LOW PRESSURE IS NEAR FWA WITH A WARM FRONT EXTENDING EAST
FROM SOUTH OF TOL TO ALONG THE SOUTHERN ERIE LAKESHORE. RADAR
MOSAIC SHOWS THE STEADY RAINSHIELD IS RAPIDLY LIFTING WAY FROM THE
REGION WITH ONLY WIDELY SCATTERED SHOWERS SOUTHWEST OF A CLE TO YNG LINE.
CIGS AND VSBY RANGE FROM IFR NEAR TOL AND FDY TO MVFR ALONG THE
LAKESHORE AND SOUTH TO MFD. SOUTHEAST FLOW NEAR TOL HAS RAISED
TEMPERATURES ABOVE FREEZING SO THE THREAT OF ZR HAS ENDED.
FRONTAL BOUNDARY WILL REMAIN NEARLY STATIONARY OVER NW OHIO UNTIL
THE LAST FRONTAL WAVE MOVES NORTHEAST UP THE BOUNDARY AND INTO
LAKE ERIE BY 12Z. COLD AIR WILL SWEEP INTO THE REGION AND IMPROVE
CIGS AND VSBY FOR A WHILE. BY MID TO LATE AFTERNOON SOME LIGHT
SNOW IS EXPECTED WHICH WILL REDUCE VSBY TO MVFR WITH CIGS NEAR
1500 FT. AFTER FRONTAL PASSAGE SOUTHWEST WINDS WILL INCREASE TO
15-20KT WITH GUSTS TO NEAR 30 KT.
.OUTLOOK...NON-VFR CONTINUES SUNDAY NIGHT. VFR MAY RETURN BRIEFLY
ON MONDAY THEN NON VFR AGAIN TUESDAY AND WEDNESDAY. BY THURSDAY
NON-VFR SHOULD BE LIMITED TO FAR NE OH/NW PA.
&&
.MARINE...
GALE WARNING STILL HOLDS FOR SUNDAY...ALTHOUGH IT MAY NEED TO BE
EXTENDED INTO SUNDAY NIGHT FOR THE EASTERN HALF OR SO. SSW WINDS
TONIGHT WILL SHIFT TO THE SW WITH THE PASSAGE OF A COLD FRONT EARLY
SUNDAY MORNING...WITH THE LOW CENTER TRACKING FROM NW OHIO INTO
QUEBEC. WIND SPEEDS WILL RAMP UP QUICKLY TO GALE FORCE WITH AND
AFTER THE FRONTS PASSAGE. WATER LEVELS WILL DROP ON THE WESTERN
BASIN TO NEAR THE CRITICAL MARK AND WILL CONTINUE TO EVALUATE THE
NEED FOR A LOW WATER ADVISORY ON SUNDAY. COLD AIR CONTINUES TO PUSH
ACROSS THE LAKE SUNDAY NIGHT AND THE GRADIENT MAY REMAIN TIGHT
ENOUGH TO KEEP LOW END WESTERLY GALES ACROSS THE EAST HALF. HIGH
PRESSURE BUILDS OVER THE OHIO VALLEY MONDAY ALLOWING WINDS TO BACK
TO THE SOUTHWEST AND BEGIN TO SLOWLY DIMINISH. SMALL CRAFT
ADVISORIES WILL LIKELY GO INTO TUESDAY MORNING FOLLOWING THE GALES.
NEXT INCREASE IN WINDS...AROUND 30 KNOTS WILL COME TUESDAY NIGHT AND
WEDNESDAY AS AN ARCTIC COLD FRONT BRINGS A SURGE OF VERY COLD AIR
OVER THE GREAT LAKES. THOSE WINDS WILL SLOWLY DIMINISH THURSDAY
AS...ONCE AGAIN HIGH PRESSURE BUILDS OVER THE OHIO VALLEY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...GALE WARNING FROM 7 AM TO 7 PM EST SUNDAY FOR LEZ061-143>149-
163>169.
&&
$$
SYNOPSIS...TK
NEAR TERM...KUBINA
SHORT TERM...TK
LONG TERM...OUDEMAN
AVIATION...LAPLANTE
MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
108 PM EST FRI JAN 2 2015
.SYNOPSIS...
SURFACE HIGH PRESSURE WILL MOVE ACROSS THE REGION TODAY. A WARM
FRONT WILL APPROACH FROM THE SOUTH TONIGHT AND PASS THROUGH THE
AREA ON SATURDAY. THIS WILL BE FOLLOWED BY A COLD FRONT SATURDAY
NIGHT WHICH WILL USHER IN MUCH COLDER AIR FOR NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHOWERS ASSOCIATED WITH A WEAK UPPER LEVEL DISTURBANCE ARE
PUSHING EAST ACROSS FAR SOUTHERN PORTIONS OF OUR FA THIS MORNING.
WE HAVE HAD SOME REPORTS OF SLEET WITH THIS AND WILL CONTINUE
WITH A MENTION OF A MIXED BAG OF PCPN THROUGH THE REST OF THIS
MORNING WITH A GRADUAL TRANSITION TO MORE RAIN AS WE SLOWLY WARM.
LATEST RAP AND HRRR SUGGEST THAT THIS PCPN SHOULD SLIDE OFF TO OUR
EAST/SOUTHEAST BY EARLY AFTERNOON. EXPECT HIGHS TODAY RANGING FROM
THE MID 30S NORTHWEST TO UPPER 30S/NEAR 40 ACROSS THE FAR SOUTH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
MODELS ARE IN FAIRLY DECENT AGREEMENT IN TERMS OF SYNOPTIC SCALE
SYSTEMS. HAVE USED A BLEND OF THE NAM/GFS/ECMWF FOR THE SHORT TERM
FORECAST.
UPR LVL LOW OVER THE DESERT SW WILL BEGIN TO EJECT NE TO THE SRN
PLAINS BY SATURDAY MORNING. AS THE HIGH MOVES OFF TO THE EAST
TONIGHT...WARM...MOIST RETURN IN THE FORM A LOW LEVEL JET WILL
BRING AN INCREASING THREAT FOR PCPN FROM SOUTH TO NORTH THROUGH
THE OVERNIGHT HOURS. WE SHOULD SEE A LITTLE DROP OFF TO
TEMPERATURES EARLY THIS EVENING...THEN AS CLOUDS THICKEN AND WINDS
INCREASE...THEY SHOULD STEADY OUT AND SLIGHTLY RISE THROUGH THE
OVERNIGHT HOURS. THE ONSET OF PCPN AND SURFACE TEMPERATURES WILL
BE CRITICAL IN FORECASTING PCPN TYPE. IT LOOKS LIKE LOCATIONS
GENERALLY ALONG AND SOUTH OF THE OHIO RIVER WILL REMAIN IN LIQUID
FORM AS TEMPERATURES REMAIN SLIGHTLY ABOVE FREEZING. POINTS TO THE
NORTH...PCPN MAY START OUT BRIEFLY AS A LITTLE SLEET...BUT WITH
TEMPERATURES AT OR SLIGHTLY BELOW FREEZING...THE THREAT FOR A
PERIOD OF FREEZING RAIN WILL EXIST AS MUCH WARMER AIR ALOFT IS
ADVECTED NORTHWARD. WITH TEMPERATURES NEAR FREEZING...ICING
ACCRETION SHOULD BE LIMITED...BUT SOME LIGHT ICING WILL LIKELY
OCCUR ON EXPOSED OBJECTS AND ELEVATED SURFACES LIKE UNTREATED
BRIDGES AND OVERPASSES. A FREEZING RAIN ADVISORY MAY BE NEEDED FOR
NORTH OF THE OHIO RIVER LATE TONIGHT INTO EARLY SATURDAY MORNING
FOR AMOUNTS GENERALLY LESS THAN A 0.10 OF AN INCH. WILL CONTINUE
TO HIGHLIGHT THE THREAT IN THE HWO PRODUCT.
ON SATURDAY...UPR LVL LOW WILL MOVE NORTHEAST TO THE CENTRAL
PLAINS BY SATURDAY EVENING. AS IT DOES...A WARM FRONT WILL LIFT
NORTH ACRS THE REGION AS SURFACE LOW PRESSURE DEEPENS TO OUR SOUTHWEST.
ANY FREEZING RAIN ACRS THE FAR NORTH SHOULD CHANGE TO ALL RAIN BY
MID MORNING AS TEMPERATURES CONTINUE TO SLOWLY WARM. FOR THE
REMAINDER OF SATURDAY...MOISTURE CONVERGENCE AND LIMITED INSTABILITY
WILL BRING SHOWERS AND PERHAPS AN ELEVATED THUNDERSTORM TO THE
REGION FOR THE REMAINDER OF THE DAY. HIGHS WILL OCCUR BY EVENING
AS LOW LEVEL FLOW TURNS SOUTHERLY. THEY SHOULD RANGE FROM NEAR 50
NORTH TO THE UPPER 50S SOUTH OF THE OHIO RIVER.
FOR SATURDAY NIGHT...UPR LVL LOW WILL PHASE WITH ENERGY FROM THE
NORTHWEST. THIS WILL CONTINUE TO DEEPEN THE SURFACE LOW AS IT MOVE
NORTHEAST THROUGH THE GREAT LAKES. A COLD FRONT WILL THEN SWING
EASTWARD THROUGH THE AREA. WIDESPREAD SHOWERS AND PERHAPS EMBEDDED
THUNDER ARE EXPECTED ALONG AND AHEAD OF THE FRONT. MODELS CONTINUE
TO ADVERTISE STRONG LOW LEVEL WINDS ALONG AND AHEAD OF THE FRONT.
THERE IS SOME CONCERN THAT THERE COULD BE SOME ENHANCED WIND GUSTS
WITH CONVECTIVE PCPN SHOULD IT TRY TO ORGANIZE INTO A LINEAR
STRUCTURE. SHERB PARAMETERS SUPPORT THIS. AM NOT READY YET TO
PLACE THE CONCERN IN THE HWO...BUT WILL CERTAINLY ANALYZE
CONVECTION ALLOWING MODELS AS WE GET CLOSER TO SATURDAY NIGHT. WE
SHOULD AT LEAST SEE SOME SYNOPTIC WIND GUSTS AROUND 30 KNOTS WITH
FRONTAL PASSAGE SATURDAY NIGHT. OVERNIGHT LOWS WILL OCCUR BY
SUNDAY MORNING AS TEMPERATURES FALL BEHIND THE FRONT. OVERALL WE
SHOULD SEE 1 TO 1.50 INCHES OF RAIN WITH THIS SYSTEM. STREAM FLOW
ACRS OUR REGION IS LOW AS IS OUR FLASH FLOOD GUIDANCE...SO THE
FLOOD THREAT OTHER THAN SOME MINOR SHORT TERM FLOODING SHOULD
REMAIN LOW AS WELL.
FOR SUNDAY...ADDITIONAL UPR LVL ENERGY ALONG WITH STRONG CAA WILL
KEEP SKIES CLOUDY ALONG WITH A THREAT OF SCATTERED RAIN AND/OR
SNOW SHOWERS. LITTLE SNOW ACCUMULATION IS EXPECTED. HIGH TEMPERATURES
WILL OCCUR EARLY WITH TEMPERATURES DROPPING THROUGH THE DAY.
BY SUNDAY NIGHT...ARCTIC HIGH PRESSURE WILL BUILD SOUTHEAST INTO
THE THE AREA. CLOUDS SHOULD DECREASE SOME ALONG WITH A TAPERING
OFF OF SCATTERED SNOW SHOWERS.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ARCTIC HIGH PRESSURE WILL WORK INTO THE AREA FOR MONDAY ALLOWING
FOR DRY CONDITIONS. TEMPERATURES WILL STRUGGLE TO RISE WITH THE
COLD AIRMASS IN PLACE. A CLIPPER WILL MOVE THROUGH THE AREA LATE
MONDAY NIGHT INTO THE DAY ON TUESDAY. TEMPERATURES WILL BE COLD
ENOUGH THAT PRECIPITATION WILL ALL BE IN THE FORM OF SNOW. THESE
TYPE OF SYSTEMS ARE TYPICALLY PRETTY EFFICIENT WITH HIGH SNOW TO
LIQUID RATIOS. MODELS HAVE COME INTO DECENT AGREEMENT ON THE
TIMING AND STRENGTH OF THIS FEATURE. THE BEST CHANCE FOR
ACCUMULATING SNOW WILL BE ACROSS NORTHERN PORTIONS OF THE FA. WITH
DECENT MODEL AGREEMENT AND THIS FEATURE SHOWING UP FOR MULTIPLE
RUNS HAVE DECIDED TO CONTINUE TO INCREASE PRECIPITATION CHANCES ON
TUESDAY.
MOST OF THE PRECIPITATION WILL TAPER OFF TUESDAY EVENING HOWEVER
SOME RESIDUAL SNOW SHOWERS WILL STICK AROUND TUESDAY NIGHT INTO
WEDNESDAY ACROSS NORTHERN PORTIONS OF THE FA WITH WINDS OFF OF THE
LAKE.
THE COLDEST TEMPERATURES OF THE LONG TERM PERIOD LOOK TO BE
WEDNESDAY NIGHT ACROSS THE AREA. HIGH PRESSURE WILL BE IN PLACE AND
THERE WILL BE SOME BREAKS IN THE CLOUDS. WITH SOME SNOW ON THE
GROUND STILL FROM THE TUESDAY SYSTEM ALSO POSSIBLE AND THE COLD
AIRMASS IN PLACE EXPECT TEMPERATURES TO DROP DOWN INTO THE SINGLE
DIGITS ACROSS MOST LOCATIONS. TEMPERATURES WILL START TO RISE
SLIGHTLY ON THURSDAY AS SOUTHERLY FLOW DEVELOPS.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
SURFACE HIGH PRESSURE WILL CONTINUE TO SHIFT OFF TO THE
EAST THROUGH LATE AFTERNOON/EARLY EVENING. AS IT DOES...THE LOW
LEVEL FLOW ACROSS OUR AREA WILL CONTINUE TO BACK AND INCREASE AS A
STRENGTHENING LOW LEVEL JET ROTATES UP INTO THE OHIO VALLEY
THROUGH SATURDAY MORNING. AN ASSOCIATED WARM FRONT WILL LIFT NORTH
ACROSS OUR AREA DURING THE DAY ON SATURDAY. INCREASING ISENTROPIC
LIFT LATER TONIGHT WILL ALLOW FOR SHOWERS TO WORK THEIR WAY NORTH
INTO OUR AREA AFTER MIDNIGHT. GIVEN THE WARMING AIR ALOFT...EXPECT
PCPN TO BE ALL LIQUID. HOWEVER...SURFACE TEMPERATURES WILL LIKELY
BE NEAR OR JUST BELOW FREEZING AS THE PCPN BEGINS AND THIS WILL
LEAD TO THE POSSIBILITY OF A BRIEF (HOUR OR TWO) PERIOD OF
FREEZING RAIN AT ONSET. WOULD EXPECT THE BEST CHANCE FOR THIS TO
BE ALONG AND NORTH OF THE I-70 CORRIDOR. AS THE PCPN
DEVELOPS...EXPECT CIGS AND VSBYS TO DROP THROUGH MVFR INTO IFR
CATEGORY LATE TONIGHT INTO SATURDAY MORNING. AS THE WARM FRONT
LIFTS NORTH AND WE START TO GET INTO THE WARM SECTOR...WE COULD
BEGIN TO SEE SOME IMPROVEMENT IN CIGS FROM THE SOUTH THROUGH THE
AFTERNOON. THIS WILL ALSO ALLOW FOR SOME WEAK INSTABILITIES TO
ADVECT NORTH INTO THE REGION SO A FEW THUNDERSTORMS WILL BE
POSSIBLE DURING THE AFTERNOON HOURS. DUE TO THE LOWER PROBABILITY
THOUGH...HAVE LEFT MENTION OF THUNDER OUT OF THE KCVG TAF ATTM.
OUTLOOK...MVFR CEILINGS AND VISIBILITIES POSSIBLE INTO SUNDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...JGL
SHORT TERM...HICKMAN
LONG TERM...NOVAK
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
832 AM EST FRI JAN 2 2015
.SYNOPSIS...
SURFACE HIGH PRESSURE WILL MOVE ACROSS THE REGION TODAY. A WARM
FRONT WILL APPROACH FROM THE SOUTH TONIGHT AND PASS THROUGH THE
AREA ON SATURDAY. THIS WILL BE FOLLOWED BY A COLD FRONT SATURDAY
NIGHT WHICH WILL USHER IN MUCH COLDER AIR FOR NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHOWERS ASSOCIATED WITH A WEAK UPPER LEVEL DISTURBANCE ARE
PUSHING EAST ACROSS FAR SOUTHERN PORTIONS OF OUR FA THIS MORNING.
WE HAVE HAD SOME REPORTS OF SLEET WITH THIS AND WILL CONTINUE
WITH A MENTION OF A MIXED BAG OF PCPN THROUGH THE REST OF THIS
MORNING WITH A GRADUAL TRANSITION TO MORE RAIN AS WE SLOWLY WARM.
LATEST RAP AND HRRR SUGGEST THAT THIS PCPN SHOULD SLIDE OFF TO OUR
EAST/SOUTHEAST BY EARLY AFTERNOON. EXPECT HIGHS TODAY RANGING FROM
THE MID 30S NORTHWEST TO UPPER 30S/NEAR 40 ACROSS THE FAR SOUTH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
MODELS ARE IN FAIRLY DECENT AGREEMENT IN TERMS OF SYNOPTIC SCALE
SYSTEMS. HAVE USED A BLEND OF THE NAM/GFS/ECMWF FOR THE SHORT TERM
FORECAST.
UPR LVL LOW OVER THE DESERT SW WILL BEGIN TO EJECT NE TO THE SRN
PLAINS BY SATURDAY MORNING. AS THE HIGH MOVES OFF TO THE EAST
TONIGHT...WARM...MOIST RETURN IN THE FORM A LOW LEVEL JET WILL
BRING AN INCREASING THREAT FOR PCPN FROM SOUTH TO NORTH THROUGH
THE OVERNIGHT HOURS. WE SHOULD SEE A LITTLE DROP OFF TO
TEMPERATURES EARLY THIS EVENING...THEN AS CLOUDS THICKEN AND WINDS
INCREASE...THEY SHOULD STEADY OUT AND SLIGHTLY RISE THROUGH THE
OVERNIGHT HOURS. THE ONSET OF PCPN AND SURFACE TEMPERATURES WILL
BE CRITICAL IN FORECASTING PCPN TYPE. IT LOOKS LIKE LOCATIONS
GENERALLY ALONG AND SOUTH OF THE OHIO RIVER WILL REMAIN IN LIQUID
FORM AS TEMPERATURES REMAIN SLIGHTLY ABOVE FREEZING. POINTS TO THE
NORTH...PCPN MAY START OUT BRIEFLY AS A LITTLE SLEET...BUT WITH
TEMPERATURES AT OR SLIGHTLY BELOW FREEZING...THE THREAT FOR A
PERIOD OF FREEZING RAIN WILL EXIST AS MUCH WARMER AIR ALOFT IS
ADVECTED NORTHWARD. WITH TEMPERATURES NEAR FREEZING...ICING
ACCRETION SHOULD BE LIMITED...BUT SOME LIGHT ICING WILL LIKELY
OCCUR ON EXPOSED OBJECTS AND ELEVATED SURFACES LIKE UNTREATED
BRIDGES AND OVERPASSES. A FREEZING RAIN ADVISORY MAY BE NEEDED FOR
NORTH OF THE OHIO RIVER LATE TONIGHT INTO EARLY SATURDAY MORNING
FOR AMOUNTS GENERALLY LESS THAN A 0.10 OF AN INCH. WILL CONTINUE
TO HIGHLIGHT THE THREAT IN THE HWO PRODUCT.
ON SATURDAY...UPR LVL LOW WILL MOVE NORTHEAST TO THE CENTRAL
PLAINS BY SATURDAY EVENING. AS IT DOES...A WARM FRONT WILL LIFT
NORTH ACRS THE REGION AS SURFACE LOW PRESSURE DEEPENS TO OUR SOUTHWEST.
ANY FREEZING RAIN ACRS THE FAR NORTH SHOULD CHANGE TO ALL RAIN BY
MID MORNING AS TEMPERATURES CONTINUE TO SLOWLY WARM. FOR THE
REMAINDER OF SATURDAY...MOISTURE CONVERGENCE AND LIMITED INSTABILITY
WILL BRING SHOWERS AND PERHAPS AN ELEVATED THUNDERSTORM TO THE
REGION FOR THE REMAINDER OF THE DAY. HIGHS WILL OCCUR BY EVENING
AS LOW LEVEL FLOW TURNS SOUTHERLY. THEY SHOULD RANGE FROM NEAR 50
NORTH TO THE UPPER 50S SOUTH OF THE OHIO RIVER.
FOR SATURDAY NIGHT...UPR LVL LOW WILL PHASE WITH ENERGY FROM THE
NORTHWEST. THIS WILL CONTINUE TO DEEPEN THE SURFACE LOW AS IT MOVE
NORTHEAST THROUGH THE GREAT LAKES. A COLD FRONT WILL THEN SWING
EASTWARD THROUGH THE AREA. WIDESPREAD SHOWERS AND PERHAPS EMBEDDED
THUNDER ARE EXPECTED ALONG AND AHEAD OF THE FRONT. MODELS CONTINUE
TO ADVERTISE STRONG LOW LEVEL WINDS ALONG AND AHEAD OF THE FRONT.
THERE IS SOME CONCERN THAT THERE COULD BE SOME ENHANCED WIND GUSTS
WITH CONVECTIVE PCPN SHOULD IT TRY TO ORGANIZE INTO A LINEAR
STRUCTURE. SHERB PARAMETERS SUPPORT THIS. AM NOT READY YET TO
PLACE THE CONCERN IN THE HWO...BUT WILL CERTAINLY ANALYZE
CONVECTION ALLOWING MODELS AS WE GET CLOSER TO SATURDAY NIGHT. WE
SHOULD AT LEAST SEE SOME SYNOPTIC WIND GUSTS AROUND 30 KNOTS WITH
FRONTAL PASSAGE SATURDAY NIGHT. OVERNIGHT LOWS WILL OCCUR BY
SUNDAY MORNING AS TEMPERATURES FALL BEHIND THE FRONT. OVERALL WE
SHOULD SEE 1 TO 1.50 INCHES OF RAIN WITH THIS SYSTEM. STREAM FLOW
ACRS OUR REGION IS LOW AS IS OUR FLASH FLOOD GUIDANCE...SO THE
FLOOD THREAT OTHER THAN SOME MINOR SHORT TERM FLOODING SHOULD
REMAIN LOW AS WELL.
FOR SUNDAY...ADDITIONAL UPR LVL ENERGY ALONG WITH STRONG CAA WILL
KEEP SKIES CLOUDY ALONG WITH A THREAT OF SCATTERED RAIN AND/OR
SNOW SHOWERS. LITTLE SNOW ACCUMULATION IS EXPECTED. HIGH TEMPERATURES
WILL OCCUR EARLY WITH TEMPERATURES DROPPING THROUGH THE DAY.
BY SUNDAY NIGHT...ARCTIC HIGH PRESSURE WILL BUILD SOUTHEAST INTO
THE THE AREA. CLOUDS SHOULD DECREASE SOME ALONG WITH A TAPERING
OFF OF SCATTERED SNOW SHOWERS.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ARCTIC HIGH PRESSURE WILL WORK INTO THE AREA FOR MONDAY ALLOWING
FOR DRY CONDITIONS. TEMPERATURES WILL STRUGGLE TO RISE WITH THE
COLD AIRMASS IN PLACE. A CLIPPER WILL MOVE THROUGH THE AREA LATE
MONDAY NIGHT INTO THE DAY ON TUESDAY. TEMPERATURES WILL BE COLD
ENOUGH THAT PRECIPITATION WILL ALL BE IN THE FORM OF SNOW. THESE
TYPE OF SYSTEMS ARE TYPICALLY PRETTY EFFICIENT WITH HIGH SNOW TO
LIQUID RATIOS. MODELS HAVE COME INTO DECENT AGREEMENT ON THE
TIMING AND STRENGTH OF THIS FEATURE. THE BEST CHANCE FOR
ACCUMULATING SNOW WILL BE ACROSS NORTHERN PORTIONS OF THE FA. WITH
DECENT MODEL AGREEMENT AND THIS FEATURE SHOWING UP FOR MULTIPLE
RUNS HAVE DECIDED TO CONTINUE TO INCREASE PRECIPITATION CHANCES ON
TUESDAY.
MOST OF THE PRECIPITATION WILL TAPER OFF TUESDAY EVENING HOWEVER
SOME RESIDUAL SNOW SHOWERS WILL STICK AROUND TUESDAY NIGHT INTO
WEDNESDAY ACROSS NORTHERN PORTIONS OF THE FA WITH WINDS OFF OF THE
LAKE.
THE COLDEST TEMPERATURES OF THE LONG TERM PERIOD LOOK TO BE
WEDNESDAY NIGHT ACROSS THE AREA. HIGH PRESSURE WILL BE IN PLACE AND
THERE WILL BE SOME BREAKS IN THE CLOUDS. WITH SOME SNOW ON THE
GROUND STILL FROM THE TUESDAY SYSTEM ALSO POSSIBLE AND THE COLD
AIRMASS IN PLACE EXPECT TEMPERATURES TO DROP DOWN INTO THE SINGLE
DIGITS ACROSS MOST LOCATIONS. TEMPERATURES WILL START TO RISE
SLIGHTLY ON THURSDAY AS SOUTHERLY FLOW DEVELOPS.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS ARE EXPECTED THROUGH THE MAJORITY OF THE TAF
PERIOD...WITH SOME DETERIORATING CONDITIONS ON SATURDAY MORNING.
MID-LEVEL CLOUDS HAVE OVERSPREAD THE REGION...AND A GRADUAL
THICKENING AND LOWERING WILL CONTINUE THROUGH TODAY AND INTO
TONIGHT. HOWEVER...CEILINGS SHOULD REMAIN VFR UNTIL AFTER
MIDNIGHT. SOME LIGHT PRECIPITATION (WHICH COULD BE A MIX OF
SNOW/SLEET/RAIN) IS MAINLY EXPECTED TO REMAIN JUST SOUTH OF THE
CINCINNATI AREA THIS MORNING...BUT SOME BRIEF PERIODS OF LIGHT
PRECIPITATION WILL BE POSSIBLE THROUGH MID-AFTERNOON. WINDS WILL
REMAIN VERY LIGHT THROUGH THE NEXT 12-18 HOURS...GRADUALLY TURNING
FROM SW TO SE.
ON SATURDAY MORNING...PRECIPITATION WILL MOVE INTO THE AREA FROM
THE SOUTH. AT THE TIME OF ONSET...A PERIOD OF FREEZING RAIN WILL
BE POSSIBLE. THIS MAY BE VERY BRIEF AT THE CINCINNATI TAF
SITES...BUT COULD LAST A COUPLE HOURS FURTHER TO THE NORTH. AS
THIS OCCURS...CEILINGS WILL GRADUALLY LOWER TO MVFR CATEGORIES.
THERE IS SOME POTENTIAL FOR CONDITIONS TO DETERIORATE FURTHER THAN
THIS...WITH IFR CEILINGS/VISIBILITIES BEING POSSIBLE...BUT THIS
WILL DEPEND ON THE INTENSITY OF THE PRECIPITATION. AS TEMPERATURES
WARM...FREEZING RAIN WILL CHANGE TO RAIN BY LATER SATURDAY
MORNING...BUT CEILINGS WILL LIKELY REMAIN LOW THROUGH THE DAY.
OUTLOOK...MVFR CEILINGS AND VISIBILITIES WILL CONTINUE INTO THE
DAY ON SATURDAY AND POSSIBLY INTO SUNDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...JGL
SHORT TERM...HICKMAN
LONG TERM...NOVAK
AVIATION...HATZOS
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1152 PM CST THU JAN 1 2015
.UPDATE...FOR 06Z AVIATION DISCUSSION
&&
.AVIATION...
STILL A LOW CONFIDENCE FORECAST WITH RESPECT TO FLIGHT CATEGORIES
AND TIMING PRECIPITATION.
-SHRA OVER EASTERN ARKANSAS COULD IMPACT THE TERMINALS THROUGH 12Z
IF THEY HOLD TOGETHER, BUT THESE WILL BEST BE HANDLED WITH A
SHORT TEMPO GROUP IF IT APPEARS THEY`LL IMPACT A TERMINAL. BETTER
CHANCES FOR PERIODS OF -SHRA/-RA WILL OCCUR AFTER 13Z. CAN`T RULE
OUT A RUMBLE OF THUNDER OR TWO FRIDAY AFTERNOON/EVENING, BUT
CONFIDENCE OF OCCURRENCE IS TOO LOW TO MENTION AT THIS TIME.
HAVE MODERATE CONFIDENCE WITH RESPECT TO FLIGHT CATEGORIES, BUT LOW
CONFIDENCE WITH RESPECT TO TIMING THE CATEGORIES. A PERIOD OF LIFR
CONDITIONS WILL EVEN BE POSSIBLE AT ALL TERMINALS AFTER 22Z, BUT
CONFIDENCE IS CURRENTLY TOO LOW TO MENTION.
WE WERE SLIGHTLY CONCERNED WITH A SHORT PERIOD OF -FZRA AT KCKV
09Z-14Z, BUT CONFIDENCE IS INCREASING THAT THIS WILL LIKELY NOT
OCCUR. EVEN IF -FZRA DOES OCCUR, IT WILL BE FOR LESS THAN AN HOUR
AT MOST. HAVE HIGH CONFIDENCE THAT NO FROZEN PRECIPITATION WILL
OCCUR AT KBNA AND KCSV.
JACKSON
&&
.PREV DISCUSSION... /ISSUED 911 PM CST THU JAN 1 2015/
UPDATE...
IN LOOKING AT REGIONAL RADAR MOSIAC TRENDS...00Z KOHX SOUNDING PROFILE...
SHORT RANGE MODEL GUIDANCE...MODEL AND BUFKIT SOUNDINGS...AND SFC
OBS...LOOKS LIKE THE BEST CHANCE FOR RAINFALL WILL BE S OF THE MID
STATE REMAINDER OF EVENING AND OVERNIGHT WITH HIGHEST POPS FOR LOCATIONS
APPROACHING THE TN/KY BORDER AND FOR SRN LOCATIONS OF THE TN RIVER VALLEY
REGION OF W MID TN. BULK OF BEST POTENTIAL OF RAINFALL LOOKS TO MOVE
INTO AREA AT OR AROUND 08Z. THUS...IN GENERAL...HAVE BACKED OFF ON POPS
FROM SW TO NE ACROSS THE MID STATE THRU REMAINDER OF EVENING AND EVEN
INTO THE FIRST FEW OVERNIGHT HOURS...PUSHING BACK THE POTENTIAL FOR
MOST RAINFALL TO THE LATER PORTION OF THE EARLY MORNING HRS. WILL
CONTINUE TO MENTION THE POSSIBILITY OF A WINTRY MIX ACROSS NRN PORTIONS
OF MID STATE...HIGHLAND RIM AND NRN PORTIONS OF UPPER CUMBERLAND...TOWARD
THE LATER PORTION OF THE EARLY MORNING HRS TOO. HOWEVER...OVERALL CHANCES
OF WINTRY MIX DEVELOPING ACROSS THESE PORTIONS OF THE MID STATE DURING
THIS TIME PERIOD LOOK TO BE LESS LIKELY THAN PREVIOUSLY THOUGHT.
PREV DISCUSSION.../ISSUED 603 PM CST THU JAN 1 2015/
UPDATE...
UPDATED THE SUITE OF FORECAST PRODUCTS TO REMOVE THE THRU LATE AFTERNOON
GROUPING IN THE ZONE FORECAST PRODUCT. ADDITIONALLY...PER CURRENT RADAR
MOSAICS AND SHORT RANGE MODEL TRENDS...ONLY WENT GO WITH A SLIGHT CHANCE
OF RAIN ACROSS N CNTRL AND UPPER CUMBERLAND REGIONS ACROSS MID STATE
THRU EARLY EVENING HRS. MOST RECENT HRLY TEMP TRENDS ALSO SUPPORTING
RAISING OVERNIGHT LOWS INTO THE MID 30S ACROSS THE PLATEAU REGION.
OTHERWISE...CURRENT FORECAST AND BELOW FORECAST REASONING REMAINS ON TRACK.
PREV DISCUSSION.../ISSUED 554 PM CST THU JAN 1 2015/
UPDATE...FOR 00Z AVIATION DISCUSSION
AVIATION...
FOR THE 00Z TAFS, THERE IS LOW CONFIDENCE WITH RESPECT TO FLIGHT
CATEGORIES, PRECIPITATION TIMING, AND EVEN PRECIPITATION TYPE.
THE OVERALL TREND WILL BE FOR DETERIORATING CONDITIONS BEGINNING
OVERNIGHT.
WE DON`T THINK IT WILL RAIN THE ENTIRE TAF CYCLE, BUT PERIODS OF
LIGHT PRECIPITATION ARE EXPECTED.
HAVE MODERATE TO HIGH CONFIDENCE THAT -RA WILL BE THE
PRECIPITATION TYPE AT KBNA AND KCSV. AT KCKV, HOWEVER, CAN`T RULE
OUT A BRIEF PERIOD OF A -RA/-FZRA MIX, ESPECIALLY 08Z-14Z.
JACKSON
PREV DISCUSSION... /ISSUED 214 PM CST THU JAN 1 2015/
DISCUSSION...WEAK HIGH PRESSURE CONTINUES TO COVER MIDDLE
TENNESSEE EARLY THIS AFTERNOON WITH A VFR OVERCAST STRATOCU DECK
KEEPING A LID ON TEMPERATURES. RADAR MOSAIC SHOWS A LARGE AREA OF
MAINLY LIGHT RAIN OVER NORTHERN MS AND EXTREME SW TN, BUT GIVEN
LARGE DEW POINT SPREADS STILL IN PLACE ACROSS THE MID STATE, RAIN
WILL BE SLOW TO ARRIVE HERE. HRRR DOES SHOW SOME DEVELOPMENT
DURING THE EVENING AND OVERNIGHT, WITH MOST OF THE ACTIVITY
REMAINING IN THE RELATIVELY WARM AIR OF SOUTHERN MIDDLE TENNESSEE.
SCATTERED ACTIVITY MAY DEVELOP ACROSS OUR NORTH BEFORE 12Z, AND UP
AGAINST THE KY STATE LINE THIS PRECIPITATION MAY START OFF AS A
RA/FZRA OR RA/IP MIXTURE, BUT ACCUMULATIONS ARE NOT EXPECTED. IN
THE MEANTIME, A DEVELOPING LOW TO OUR SW WILL COME RACING NE`WD
INTO THE OZARKS BY 12Z SATURDAY, BRINGING A WARM FRONT NORTHWARD
ACROSS MIDDLE TENNESSEE SO THAT TEMPERATURES SATURDAY MAY WARM
INTO THE 60`S OFF THE PLATEAU. MODEL SOUNDINGS DO SHOW SOME
ELEVATED INSTABILITY WITH THIS SYSTEM, SO WILL INCLUDE TS IN THE
FORECAST FOR SATURDAY AND SATURDAY NIGHT. CAN`T COMPLETELY RULE
OUT A THUNDERSTORM OR TWO PRIOR TO 12Z SATURDAY, BUT THE BEST
INSTABILITY WON`T OCCUR UNTIL DURING THE DAY, SO WILL LIMIT TS TO
DAY 3 ONLY. SPC ALSO HAS US IN A GENERAL THUNDERSTORM AREA ON DAY
3, WITH FROPA OCCURRING BETWEEN 00Z AND 12Z SUNDAY. THERE WILL
LIKELY BE SOME LEFTOVER RAIN ON SUNDAY, BUT THEN LOOK FOR DRY
WEATHER FROM SUNDAY NIGHT AT LEAST THROUGH THURSDAY. TEMPERATURES
NEXT WEEK WILL REMAIN COLDER THAN NORMAL AS WE NEVER DO REALLY
ESTABLISH ANY MEANINGFUL RETURN FLOW, SO IT`S GOING TO A COLD
WEEK.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
JBW/JJ
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
548 PM CST SAT JAN 3 2015
.AVIATION...
DOWNSLOPE WESTERLY COMPONENT EARLY THIS EVENING SHOULD KEEP
SURFACE SATURATION FROM OCCURRING...THOUGH CANNOT COMPLETELY RULE
THIS OUT BY 03Z-06Z JUST BEFORE THE NEXT FRONT ARRIVES. THE LATEST
HIGH RESOLUTION HRRR RUN SHOWS SATURATION DEVELOPING NOT FAR FROM
EITHER KPVW OR KLBB BY THIS TIME SO WE WILL BE KEEPING A CLOSE EYE
ON TRENDS. OTHERWISE...EXPECTING MUCH IMPROVED CONDITIONS THOUGH
ARRIVAL OF A COLD FRONT AROUND 05Z-06Z FOR EACH SITE. SOME
POSSIBILITY OF A LOW CLOUD LAYER POST-FRONT AS INDICATED WITH THE
SCT020 LAYER. ONCE AGAIN...WE WILL CLOSELY FOLLOW TRENDS THOUGH
CURRENT INDICATIONS SUPPORT MUCH DRIER AND COLDER AIR BEHIND THIS
FRONT WHICH SHOULD FAVOR VFR CONDITIONS. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 255 PM CST SAT JAN 3 2015/
SHORT TERM...
THE STORM SYSTEM THAT BROUGHT THE VARIETY OF WINTRY PRECIPITATION TO
THE REGION THE PAST COUPLE OF DAYS WAS FINALLY ACCELERATING AWAY TO
THE NORTHEAST. HOWEVER...IT DID NOT GO QUIETLY...WITH AN AREA OF
WRAP AROUND SNOW IMPACTING MUCH OF THE NORTHERN HALF OF THE CWA
THROUGH EARLY AFTERNOON...BRINGING ADDITIONAL SNOWFALL RANGING FROM
A LIGHT DUSTING TO A QUICK 2 INCHES. THE BIGGEST SNOWFALL WINNERS
FOR THE EVENT WERE ACROSS OUR FAR NORTHWEST ZONES WITH FRIONA
REPORTING A HALF FOOT AND RHEA COMING IN WITH 9 INCHES. THE SNOW HAS
SINCE DIMINISHED AND MOST SPOTS WERE NOW SEEING SOME SUN AND BRISK
WESTERLY WINDS WHICH HAVE ALLOWED TEMPERATURES TO CLIMB TO AND ABOVE
THE FREEZING MARK. THIS WAS HELPING TO THAW THINGS OUT...THOUGH WAS
ALSO CREATING THE RISK OF FALLING ICE WHERE SIGNIFICANT FREEZING
RAIN OCCURRED YESTERDAY.
ALTHOUGH WE HAVE SEEN A RELATIVE WARM-UP THIS AFTERNOON...IT IS
STILL TOO EARLY TO BREAK OUT THE SHORTS AND FLIP FLOPS. INSTEAD...WE
WILL SEE ANOTHER COLD FRONT PLUNGE THROUGH THE SOUTH PLAINS TONIGHT
BEHIND THE DEPARTING UPPER LOW AND UNDER DEVELOPING DRY NORTHWEST
FLOW ALOFT. THE FRONT OF INTEREST IS CURRENTLY MOVING THROUGH
EASTERN COLORADO AND NORTHWEST KANSAS AND IS PROGGED TO MOVE THROUGH
THE SOUTH PLAINS AROUND AND SHORTLY AFTER MIDNIGHT. BREEZY NORTHERLY
WINDS AND COLD ADVECTION BEHIND THE FRONT WILL RESULT IN A CHILLY
NIGHT. TEMPERATURES ACROSS THE DEEPEST SNOWPACK OF OUR NORTHWEST
ZONES MAY DIP INTO THE SINGLE DIGITS...WHILE TEENS WILL BE COMMON
OVER MUCH OF THE REMAINDER OF THE FA. THE COLD TEMPERATURES AND
BREEZY WINDS WILL DROP WIND CHILLS INTO THE SINGLE DIGITS AT MANY
LOCATIONS EARLY SUNDAY...WITH A FEW BELOW ZERO READING ACROSS THE
FAR NORTHWEST. THAT SAID...IT DOES APPEAR WIND CHILL VALUES WILL
COME UP JUST SHY OF ADVISORY LEVELS...THOUGH IT WILL BE COLD
NONETHELESS. A SHORT-LIVED DECK OF STRATUS CLOUDS COULD EVEN FOLLOW
THE FRONT...BUT SHOULD QUICKLY SHIFT TO THE SOUTHWEST AND WEST ON
SUNDAY. AREAS OF FREEZING FOG COULD ALSO DEVELOP NEAR THE TX/NM LINE
EARLY SUNDAY...THOUGH IT APPEARS THE BETTER SHOT WILL BE IN EASTERN
NM AND WE HAVE LEFT THE MENTION OUT OF THE FORECAST ATTM. EVEN
SO...THE SURFACE RIDGE BUILDING IN BEHIND THE COLD FRONT WILL KEEP
TEMPERATURES CHILLY TOMORROW...WITH HIGHS ONLY EXPECTED TO RISE INTO
THE UPPER 20S AND LOWER 30S.
LONG TERM...
BROAD CYCLONIC FLOW TO REMAIN ACROSS MUCH OF THE CONUS NEXT
WEEK...ALTHOUGH WILL SEE RIDGING DEVELOP OVER THE WEST COAST AND
EASTERN PACIFIC THEN SLOWLY EDGE EWD WITH TIME. THIS PATTERN WILL
KEEP BELOW NORMAL TEMPS IN PLACE THROUGH THE WEEK WITH MODEL PROGS
SHOWING SHARPLY COLDER TEMPS WEDNESDAY AS THE NEXT PIECE OF COLD
AIR DROPS SWD INTO THE EASTERN TWO-THIRDS OF THE CONUS WITH
ANOTHER WEAKER BUT STILL COLD PIECE MOVING SWD LATE IN THE WEEK.
OTHER ITEM TO WATCH IS A SHORT WAVE TROUGH PROGGED TO MOVE EWD
ACROSS THE DESERT SW AND/OR NRN MEXICO POSSIBLY SPREADING SOME
LIGHT PRECIP ACROSS THE FCST AREA TOWARD SATURDAY. STILL A LOT OF
UNCERTAINTY WITH THIS TROUGH. WITH MODELS CONTINUING TO FAVOR THE
SERN ZONES WILL KEEP A SLIGHT MENTION THERE.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 8 28 16 42 24 / 0 0 0 0 0
TULIA 12 28 15 41 22 / 0 0 0 0 0
PLAINVIEW 13 29 17 41 24 / 0 0 0 0 0
LEVELLAND 15 32 18 43 27 / 0 0 0 0 0
LUBBOCK 15 30 19 42 26 / 0 0 0 0 0
DENVER CITY 18 31 18 41 26 / 0 0 0 0 0
BROWNFIELD 17 30 18 41 26 / 0 0 0 0 0
CHILDRESS 15 29 17 38 23 / 0 0 0 0 0
SPUR 19 29 17 40 27 / 0 0 0 0 0
ASPERMONT 21 31 18 45 27 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/05
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
345 PM CST FRI JAN 2 2015
.DISCUSSION...
A WARM FRONT OVER THE WATERS THIS MORNING HAS CONTINUED TO PUSH
NORTH AND HAS STARTED TO MOVE INLAND. THIS HAS ALLOWED DENSE SEA
FOG TO START TO MOVE INLAND AS WELL. DUE TO THIS HAVE EXTENDED
THE DENSE FOG ADVISORY UNTIL 6 AM TOMORROW MORNING AND HAVE ALSO
ADDED BRAZORIA... CHAMBERS...HARRIS... AND LIBERTY COUNTIES.
GFS... EURO... AND CANADIAN ARE ALL IN AGREEMENT WITH RAIN
CHANCES INCREASING STARTING AFTER MIDNIGHT TONIGHT INTO SATURDAY
MORNING. JET DYNAMICS AGAIN LOOK PRETTY GOOD WITH SOUTHEAST TEXAS
BEING IN A RRQ AND LFQ. FORECAST SOUNDINGS FOR THE GFS AND NAM
BOTH SHOW K INDEX VALUES AROUND 37 EARLY TOMORROW MORNING WITH
PWATS RANGING FROM 1.45 TO AROUND 1.60" (AROUND TO JUST UNDER +2
SD FOR THIS TIME OF YEAR). HIGH RES RAP HAS PERFORMED THE BEST
TODAY AND DOES NOT HAVE THAT IMPRESSIVE OF RAINFALL TOTALS FOR
TOMORROW MORNING WHILE THE NAM AND EURO HAVE AROUND 0.5" TO 1.50"
TOTAL FOR THE EVENT. THE STRONG UPPER LIFT IS HARD TO IGNORE AND
WILL GO WITH GFS/ EURO CONSENSUS ON RAINFALL TOTALS. THE HIGHEST
PRECIP TOTALS DUE APPEAR TO BE TOWARDS PORT AUTHOR THOUGH.
THE RAIN WILL MOVE OUT OF THE AREA SATURDAY WITH CLEARING SKIES
BEHIND IT. A STRONGER ARCTIC FRONT WILL THEN MOVE THROUGH THE AREA
SUNDAY MORNING. AHEAD OF THE FRONT SOME PATCHY FOG CAN BE EXPECTED
AS WINDS WEAKEN AND SKIES GO MOSTLY CLEAR. DEWPOINT DEPRESSION
FIELD FROM THE NAM SUPPORTS THIS. AT THE SAME TIME AN UPPER LEVEL
LOW WILL FORM OVER THE BAJA OF CALIFORNIA AND BEGIN TO RETROGRADE.
THE LOW WILL THEN MOVE UNDERNEATH A RIDGE OF HIGH PRESSURE FORMING
A REX BLOCK. THE CANADIAN AND EURO ARE AGAIN IN GOOD AGREEMENT
HERE. THE GFS CONTINUES TO TREND TOWARDS THE CANADIAN/ EURO
SOLUTION. THE EURO THEN BRINGS A MUCH STRONGER FRONT THROUGH THE
AREA EARLY WEDNESDAY. THE EURO AND CANADIAN BRING A 1050MB HIGH
DOWN WITH A 1043 HIGH SETTLING OVER SAN ANGELO THURSDAY MORNING.
THE EURO AND CANADIAN ALMOST LOOK IDENTICAL THURSDAY MORNING.
GIVEN THE CONSISTENCY BETWEEN THE EURO AND CANADIAN HAVE TRENDED TEMPS
DOWN SLIGHTLY THURSDAY MORNING. 23
&&
.MARINE...
A WARM FRONT CONTINUES TO ENCROACH ON THE COAST AND SFC DEW PTS OVER
THE WATER HAVE WARMED INTO THE LOWER 60S. WATER TEMPS ARE IN THE
UPPER 50S AND THIS HAS LED TO SOME SEA FOG. FEEL THE THREAT FOR FOG
WILL PERSIST FOR MUCH OF THE NIGHT AND WILL EXTEND THE DENSE FOG
ADVISORY OVER THE WATER THROUGH 12Z. SCATTERED SHRA/TSRA WILL BECOME
MORE NUMEROUS TONIGHT INTO SATURDAY AS A COLD FRONT APPROACHES THE
AREA. CONVECTION WILL PROVIDE SOME MIXING FROM TIME TO TIME BUT FEEL
THE OVERALL TREND WILL FAVOR LOW VSBY IN FOG. ALTHOUGH WINDS HAVE
DIMINISHED...FEEL TIDE LEVELS WILL REMAIN SLIGHTLY ELEVATED UNTIL A
PACIFIC COLD FRONT USHERS IN AN OFFSHORE FLOW ON SATURDAY MORNING. A
SECONDARY SURGE OF COLDER AIR ON SUNDAY WILL MOVE OVER THE WARMER
GULF WATERS AND THE STRONG CONTRAST IN TEMPS WILL PROVIDE FOR A
STRONG THERMAL GRADIENT AND OFFSHORE WIND SPEEDS WILL INCREASE. AN
SCA WILL LIKELY BE REQUIRED SUNDAY AND SUNDAY NIGHT. ANOTHER FRONT
WILL CROSS THE COASTAL WATERS ON WEDNESDAY WITH ANOTHER SCA LIKELY
AT THAT TIME. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 44 58 38 48 29 / 100 50 0 0 0
HOUSTON (IAH) 51 60 42 53 33 / 100 60 0 0 0
GALVESTON (GLS) 57 60 47 53 40 / 90 80 10 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL 6 AM CST SATURDAY FOR THE FOLLOWING
ZONES: BRAZORIA...CHAMBERS...GALVESTON...HARRIS...LIBERTY.
GM...DENSE FOG ADVISORY UNTIL 6 AM CST SATURDAY FOR THE FOLLOWING
ZONES: GALVESTON BAY...WATERS FROM HIGH ISLAND TO FREEPORT
OUT 20 NM.
&&
$$
DISCUSSION...23
AVIATION/MARINE...43
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1157 PM CST THU JAN 1 2015
.AVIATION...
/06Z TAFS/
ISENTROPIC LIFT WILL CONTINUE LATE THIS EVENING THROUGH FRIDAY
WITH IFR/LIFR CIGS/VBSYS CATEGORY PREVAILING FOR MOST OF THE
FORECAST CYCLE. LIGHT RAIN/DRIZZLE WILL CONTINUE TO AFFECT THE
I-35 SITES...ESPECIALLY THE AUSTIN AREA AIRPORTS AND KSAT. ANOTHER
AVIATION CONCERN FOR THIS PACKAGE WILL BE AREAS OF PATCHY TO DENSE
FOG DEVELOPING OVERNIGHT AND EARLY FRIDAY MORNING. SO FAR...HI-RES
MODELS SUGGEST AREAS OF DENSE FOG OVER PART OF THE ESCARPMENT AND
NORTHERN PART OF THE HILL COUNTRY AND JUST TO THE NORTHWEST OF
KAUS. HAVE ADDED A TEMPO GROUP TO KAUS SHOWING THE POTENTIAL OF
AREAS OF DENSE FOG ACROSS THE AIRPORT FROM 10Z TO 14Z FRIDAY.
FLYING CONDITIONS WILL NOT IMPROVE FROM THE LIFR CATEGORY UNTIL
LATE FRIDAY AFTERNOON WITH CIGS/VSBYS ONLY IMPROVING TO IFR FOR
COUPLE OF HOURS BEFORE DROPPING ONCE AGAIN INTO LIFR. THERE COULD
BE ISOLATED THUNDERSTORMS OUT WEST BY FRIDAY MORNING AND SHIFTING
EASTWARD DURING THE AFTERNOON HOURS. AT THIS TIME...OPTED TO KEEP
OUT MENTIONING TS AT TAF SITES DUE TO LOW CONFIDENCE ON TIMING AND
AERIAL COVERAGE.
&&
.PREV DISCUSSION... /ISSUED 934 PM CST THU JAN 1 2015/
UPDATE...INCREASED POPS ACROSS CENTRAL AND WESTERN ZONES FOR THE
OVERNIGHT THROUGH 6AM GIVEN RADAR TRENDS AND OBSERVATIONS INDICATING
THE LIGHT DRIZZLE REACHING THE SURFACE. ALSO INCREASED POPS BY ABOUT
10% FOR TOMORROW GIVEN HRRR/HI-RES OUTPUT. HOURLY TEMPERATURES AND
DEWPOINTS WERE MASSAGED TO ACCOUNT FOR CURRENT TRENDS. SEE UPDATED
DISCUSSION BELOW FOR MORE DETAILS.
DISCUSSION...AREAS OF FOG AND WIDESPREAD LIGHT RAIN SHOWERS AND DRIZZLE
IS ONGOING ACROSS MUCH OF THE REGION THIS EVENING. MOIST
ISENTROPIC UPGLIDE CONTINUES TO AID IN LIGHT PRECIPITATION
DEVELOPMENT AND THIS IS EXPECTED TO PERSIST THROUGH THE OVERNIGHT.
HAVE BUMPED UP POPS ACCORDINGLY AND ADDED A FEW HUNDREDTHS MORE TO
RAINFALL ACCUMULATION TOTALS. WHILE ALL AREAS ARE ABOVE
FREEZING...AREAS IN NORTHERN EDWARDS COUNTY ARE CLOSE TO THAT MARK
WITH ROCKSPRINGS AT 34 DEGREES AND SONORA AT 32 DEGREES. ALL SHORT
TERM GUIDANCE DOES KEEP AREA ABOVE FREEZING OVERNIGHT AND DONT
EXPECT ANY FREEZING RAIN ACROSS SOUTHERN EDWARDS PLATEAU IN THIS
PARTICULAR AREA.
FOR FRIDAY MORNING AND INTO THE AFTERNOON...HI-RES AND HRRR GUIDANCE
ARE INDICATING SLIGHTLY MORE ORGANIZED RAIN SHOWER BANDING AS
INCREASED LIFT OCCURS IN ADVANCE OF SHORTWAVE TROUGH PASSAGE. SOME
OF THIS BANDING COULD HAVE EMBEDDED THUNDERSTORM ACTIVITY GIVEN
SOME SUPPORT FROM NEAR 7C H7-H5 LAPSE RATES LEADING TO 300-600
J/KG MUCAPE PER EC AND NAM. HAVE INCREASED RAINFALL AMOUNTS
UPWARD ABOUT 0.05 TO 0.1" FOR THE SOUTHERN HILL COUNTRY AND JUST
NORTH AND WEST OF THE I-35 CORRIDOR IN THE 6AM TO NOON TIME FRAME.
A SMALL BREAK LOOKS TO OCCUR DURING THE AFTERNOON BEFORE ANOTHER
ROUND OF RAIN OCCURS OVERNIGHT FRIDAY INTO SATURDAY MORNING AS THE
MAIN TROUGH AXIS MOVES OVER THE AREA AND DRIER AIR MOVES IN.
/ALLEN/
PREV DISCUSSION... /ISSUED 554 PM CST THU JAN 1 2015/
AVIATION...
/00Z TAFS/
CIGS AND VBSYS WILL NOT IMPROVE MUCH THROUGH THE FORECAST PERIOD
WITH IFR/LIFR CONDITIONS. EXPECT LIGHT RAIN/DRIZZLE AND PATCHY FOG
ACROSS THE AREA AIRPORTS AS ISENTROPIC LIFT CONTINUES TO DOMINATE
ALOFT WITH A COOLER AIRMASS AT THE SURFACE. LOW LEVEL WINDS WILL
BE FROM THE NORTH AND NORTHEAST AND EVEN VARIABLE TONIGHT INTO
FRIDAY. THERE IS A SLIGHT CHANCE FOR ISOLATED THUNDERSTORMS ACROSS
SOUTH CENTRAL TEXAS ON FRIDAY AS AN UPPER LEVEL TROUGH PUSHES
ACROSS THE DESSERT SOUTHWEST INTO THE SOUTHERN PLAINS. HOWEVER...
AT THIS TIME...OPTED TO KEEP TS OUT. WILL REVISIT DURING THE 06Z
PACKAGE.
PREV DISCUSSION... /ISSUED 328 PM CST THU JAN 1 2015/
SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)...
WITH THE FREEZING LINE NOW JUST NORTH OF THE CWA...A EVENING AND
OVERNIGHT PERIOD OF COLD LIGHT RAIN...DRIZZLE...AND FOG ARE IN
STORE. WITH VISIBILITIES NEVER REACHING ABOVE 6 SM ACROSS THE
CWA...DIDNT THINK THEY WOULD IMPROVE ANY OVER THE NEXT 24 HOURS AS
THE SAME MOISTURE LOOKS TO BE IN PLACE UNTIL THE UPPER LEVEL
SYSTEM CLEARS OUT SUNDAY. THEREFORE INCLUDED AREAS OF FOG FOR THE
CWA THROUGH FRIDAY.
CONTINUAL OVERRUNNING AND THE SLOW EASTWARD TRANSLATION OF THE UPPER
LEVEL LOW WILL KEEP POP CHANCES HIGH FOR THE NORTH AND EAST ZONES
THROUGHOUT THE NEXT 24 HOURS. ELEVATED LAPSE RATES CONTINUED TO BE
STEEP AND WITH MORNING CONVECTION TODAY RESULTING IN SOME
LIGHTNING STRIKES...LEFT ISO T MENTION IN THE WX GRID THROUGH FRIDAY.
EVEN THOUGH RAIN WILL BE IN THE FORECAST THROUGH SATURDAY
MORNING...QPF VALUES SHOULD STAY BELOW CONCERNABLE VALUES DUE TO
THE FACT THE RAIN SHOULD STAY LIGHT. CURRENTLY...THE TOTAL QPF
FORECAST BETWEEN TONIGHT AND SATURDAY IS LESS THAN AN INCH ACROSS
THE CWA.
LONG TERM (SATURDAY THROUGH THURSDAY)...
THE UPPER LEVEL SYSTEM WILL FINALLY CLEAR OUT OF THE AREA SATURDAY
FROM THE WEST TO THE EAST. LATER IN THE EVENING...A STRONG BUT DRY
CP AIR MASS WILL DIVE SOUTH OUT OF THE PANHANDLE BRINGING GUSTY
WINDS SUNDAY DUE TO A RAPIDLY TIGHTENING PRESSURE GRADIENT...AND A
VERY COLD MORNING ON MONDAY. GUIDANCE IS CURRENTLY SUGGESTING
TEMPERATURES IN THE LOWER 20S IN THE NORTH AND AROUND 30 IN OUR
SOUTHERNMOST LOCATIONS SO IF THE FORECAST HOLDS...THE REMAINING
COUNTIES THAT HAVE NOT REACHED A WIDESPREAD FREEZE WILL DO SO COME
MONDAY.
THIS COOL PATTERN OF COLD MORNINGS AND COOL DAYS WILL PERSIST
THROUGH THE EXTENDED. A UPPER LEVEL RIDGE WILL MOVE OVER THE ROCKY
MOUNTAINS BY THURSDAY WHILE A WEAK DISTURBANCE FROM BAJA CREEPS
INTO THE SOUTHWEST. THIS MAY BRING SHOWER ACTIVITY BACK INTO THE
FORECAST TOWARDS THE END OF THE WEEK. MORE TO COME ON THIS AS
LATER MODEL RUNS PROVIDE MORE CLARITY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 37 42 40 59 36 / 80 90 90 20 10
AUSTIN BERGSTROM INTL AIRPORT 38 44 39 60 36 / 80 80 90 20 10
NEW BRAUNFELS MUNI AIRPORT 39 45 40 63 37 / 70 80 90 20 10
BURNET MUNI AIRPORT 35 40 35 57 32 / 80 80 90 20 10
DEL RIO INTL AIRPORT 37 49 40 63 37 / 60 60 60 - 0
GEORGETOWN MUNI AIRPORT 36 42 38 58 34 / 80 90 90 20 10
HONDO MUNI AIRPORT 38 47 39 63 35 / 60 70 70 10 10
SAN MARCOS MUNI AIRPORT 38 44 39 61 36 / 70 80 90 20 10
LA GRANGE - FAYETTE REGIONAL 41 47 44 60 38 / 80 80 90 40 10
SAN ANTONIO INTL AIRPORT 39 46 41 62 36 / 70 80 90 20 10
STINSON MUNI AIRPORT 40 46 40 63 37 / 70 70 80 20 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...17
SYNOPTIC/GRIDS...15
YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1105 AM CST FRI JAN 2 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 301 AM CST FRI JAN 2 2015
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A SHORTWAVE TROUGH OVER THE YUKON OF CANADA...A POTENT UPPER
TROUGH OVER NORTHERN BRITISH COLUMBIA...UPPER LOWS OVER ARIZONA AND
THE DENVER AREA...AND BROAD UPPER TROUGHING OVER EASTERN CANADA INTO
THE GREAT LAKES. WITH THE FORECAST AREA UNDER THE NORTHWEST FLOW ON
THE EDGE OF THIS UPPER TROUGHING...SUBSIDENCE AND DRYING HAS BEEN
OCCURRING. THIS HAS TRANSLATED INTO CLEARING SKIES IN THE WAKE OF A
SURFACE COLD FRONTAL PASSAGE DURING THE NIGHT. A BIT OF ARCTIC AIR
HAS BEEN SPILLING INTO NORTHERN WISCONSIN...NORTH OF HIGHWAY 29...
REFLECTED BY 925MB TEMPS DROPPING TO -12 TO -16C THERE AND SURFACE
TEMPERATURES IN THE SINGLE DIGITS ABOVE AND BELOW ZERO. READINGS ARE
MOSTLY IN THE TEENS ELSEWHERE IN THE FORECAST AREA. ONLY OTHER ITEM
OF NOTE WAS A LOOK AT PRECIPITABLE WATER VALUES FROM 00Z RAOBS. MOST
READINGS ACROSS THE CENTRAL/NORTHERN PLAINS AND OUR REGION WERE
BETWEEN 0.2 AND 0.35...FAIRLY DRY. HOWEVER...0.7-1 INCH VALUES WERE
PRESENT ACROSS THE SOUTHERN PLAINS AHEAD OF THE ARIZONA UPPER LOW.
MUCH OF THE SHORT TERM PERIOD IS QUIET THANKS TO THE DRY AIRMASS IN
PLACE REFLECTED BY 00Z RAOBS. HOWEVER...AS WE GET INTO THE AFTER
MIDNIGHT HOURS TONIGHT...THE 02.00Z GFS AND NAM SPREAD SOME LIGHT
QPF FROM THE SOUTH INTO CLAYTON/GRANT COUNTY AREA. THE 02.06Z
NAM/02.00Z ECMWF TAKE IT ONE STEP FURTHER AND SPREAD IT ALL THE WAY
THROUGH ABOUT THE EAST HALF OR MORE OF THE FORECAST AREA. MUCH OF
THIS QPF IS A RESULT OF AN ISENTROPIC LIFT / WARM ADVECTION REGIME
DEVELOPING DOWNSTREAM OF THE ARIZONA UPPER LOW...WHICH BY 12Z
SATURDAY IS PROGGED TO BE IN WEST TEXAS. ADDITIONALLY...WE HAVE THAT
UPPER LOW NEAR DENVER COMING THROUGH TO ADD IN SOME DPVA FORCING.
HAVE ADDED 20-40 PERCENT CHANCES INTO THE FORECAST FOR THIS FEATURE
AND THESE MAY NEED TO BE INCREASED LATER TODAY. MUCH OF THE LIFT IS
TAKING PLACE BETWEEN 10 KFT-15 KFT...BUT ENOUGH LOW LEVEL SATURATION
OCCURS TO ALLOW SNOW TO REACH THE SURFACE. IT SHOULD BE
NOTED...THOUGH...AS WE APPROACH 12Z THE ICE BEGINS TO EXITS THE
CLOUDS IN BOTH THE 02.00Z/06Z NAM AND GFS. SO...ANY LINGERING LIFT
APPROACHING THIS TIME COULD RESULT IN FREEZING DRIZZLE. HAVE ADDED
THIS POTENTIAL TO THE FORECAST. PROBABILITY FOR THIS FREEZING
DRIZZLE IS TOO LOW FOR AN ADVISORY AT THIS TIME.
WITH THE WARM ADVECTION REGIME DEVELOPING OVER THE NEXT 24 HOURS...
THE ARCTIC AIR TRYING TO SPILL INTO FAR NORTHERN SECTIONS OF THE
FORECAST AREA RIGHT NOW WILL STRUGGLE MAKING IT FARTHER SOUTH. IN
FACT...BY 00Z THIS EVENING...925MB TEMPS ALREADY ARE PROGGED FROM
-5C SOUTHWEST TO -9C NORTHEAST. WITH WHAT SHOULD BE A MOSTLY SUNNY
DAY...ANTICIPATE HIGHS CAN TOP OUT IN THE TEENS OVER TAYLOR/CLARK
COUNTIES TO THE 20S OVER THE REST OF THE SNOW PACK AREAS...AND LOW
30Z OVER SNOW FREE AREAS. WARM ADVECTION PERSISTS TONIGHT...WHICH
WITH CLOUDS INCREASING OVERNIGHT SHOULD HELP SOMEWHAT ON
TEMPERATURES. HOWEVER...WITH A MOSTLY CLEAR EVENING AND A WEAK
GRADIENT...READINGS COULD DROP INTO THE SINGLE DIGITS OVER
TAYLOR/CLARK TO THE TEENS TO LOW 20S ELSEWHERE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 301 AM CST FRI JAN 2 2015
THE FOCUS FOR SATURDAY AND SATURDAY NIGHT CONTINUES TO REVOLVE
AROUND THE CURRENT UPPER LOW IN ARIZONA AND THE SHORTWAVE TROUGH
OVER BRITISH COLUMBIA. IT APPEARS THE MAIN ROLE OF THE BRITISH
COLUMBIA SHORTWAVE IS TO SERVE AS A KICKER FOR THE UPPER LOW. GOOD
MODEL CONSENSUS EXISTS FOR THE UPPER LOW TO TRACK THROUGH THE
DAVENPORT IA AREA AROUND 06Z SUNDAY AND INTO LOWER MICHIGAN BY 12Z
SUNDAY. HOWEVER...THE BRITISH COLUMBIA TROUGH DOES SPLIT APART WITH
A SHORTWAVE THAT COMES OFF IT WHICH MODELS BRING THROUGH THE
FORECAST AREA SATURDAY NIGHT. THAT SHORTWAVE EVENTUALLY PHASES WITH
THE UPPER LOW OVER LOWER MICHIGAN...RESULTING IN A DEEPENING SURFACE
LOW WELL OFF TO OUR EAST.
THE ISENTROPIC LIFT REGIME THAT DEVELOPED TONIGHT LOOKS TO PERSIST
THROUGH SATURDAY...THOUGH MAINLY FOCUSED OVER THE SOUTHEAST 1/3 TO
1/2 OF THE FORECAST AREA. THUS...THIS IS WHERE THE MAIN FOCUS FOR
PRECIPITATION EXISTS. AGAIN...BOTH THE 02.00Z NAM AND GFS POINT TO
WAVES OF ICE IN AND OUT OF THE CLOUDS...THUS THE FORECAST INCLUDES A
MENTION OF BOTH SNOW AND DRIZZLE/FREEZING DRIZZLE. WITH A GREATER
CHANCE FOR PRECIPITATION...MAY NEED AN ADVISORY FOR THIS WINTRY MIX
ASPECT. BEING DURING THE DAYTIME AND TEMPERATURES PERHAPS CLIMBING
ABOVE THE FREEZING MARK...THIS SHOULD HELP LIMIT ICE ACCUMULATION.
PRECIPITATION CHANCES INCREASE ACROSS THE ENTIRE FORECAST AREA
SATURDAY NIGHT WITH THE CROSSING OF THE SHORTWAVE AND BRUSH BY FROM
THE UPPER LOW. THE DEFORMATION SNOW BAND ACCOMPANYING THE NORTHWEST
SIDE OF THE DEEPENING SURFACE LOW MAY CLIP THE SOUTHEAST 1/3 OF THE
FORECAST AREA...THUS HIGHEST PRECIPITATION CHANCES AND QPF ARE
CONFINED THERE. PRECIPITATION SHOULD DIMINISH WEST TO EAST QUICKLY
LATE IN THE NIGHT AS SUBSIDENCE AND MUCH COLDER AND DRIER AIR ADVECT
IN. SNOWFALL AMOUNTS OVERALL HAVE COME DOWN QUITE A BIT WITH THE
02.00Z CYCLE...INCLUDING WITH THE 02.00Z ECMWF. THIS DECLINE IS A
COMBINATION OF THE AFOREMENTIONED WINTRY MIX AND MODELS NOT NEARLY
AS IMPRESSIVE WITH THE DEFORMATION BAND. IT SHOULD BE NOTED THAT THE
02.06Z NAM AND TO SOME DEGREE THE 02.00Z ECMWF HAVE THE DEFORMATION
BAND MISS MUCH OF THE FORECAST AREA...WITH MUCH OF THE PRECIP FOCUS
ON THE SNOW ACCOMPANYING THE SHORTWAVE. IF THIS HAPPENS...EVEN LESS
SNOW WILL FALL OVER THE SOUTHEAST 1/2 OF THE AREA.
FOCUS FOR THE REST OF THE FORECAST TURNS TO ARCTIC AIR. WE HAVE TWO
BIG BLASTS TO CONTEND WITH...THE FIRST COMING IN LATE SATURDAY NIGHT
AND THE SECOND COMING IN TUESDAY NIGHT. BOTH BLASTS HAVE A 35-45 KT
925MB WINDS CORE COMING ACROSS...WHICH MEANS THERE IS POTENTIAL WIND
SPEEDS COULD TRY TO APPROACH ADVISORY CRITERIA. HOWEVER...THE ARCTIC
AIR ACCOMPANYING THE WIND WILL FORCE WIND CHILL AS THE BIGGER
HAZARD. HOW COLD WE GET WILL DEPEND SOMEWHAT ON HOW MUCH SNOW WE GET
OVER THE NEXT FEW DAYS GIVEN THE LACK OF SNOW OVER THE SOUTHEAST
HALF OF THE FORECAST AREA. DETAILS...925MB TEMPS FALL FROM -4 TO -9C
AT 06Z SUNDAY TO -23 TO -26C BY 00Z MONDAY AND -26 TO -30C BY 12Z
MONDAY...WHICH MEANS TEMPERATURES SHOULD JUST FALL THROUGH THE DAY
SUNDAY...WITH MUCH OF THE NORTHWEST HALF BELOW ZERO FOR MUCH OF THE
DAY. WIND CHILL ADVISORIES LOOK LIKELY FOR THE NORTHWEST HALF ON
SUNDAY...EXPANDING EVERYWHERE SUNDAY NIGHT INTO MONDAY WITH MAYBE
SOME WARNINGS FOR TAYLOR/CLARK AND SOUTHEAST MN. THERE IS A BRIEF
WARM UP FOR MONDAY NIGHT INTO TUESDAY AS A NORTHWEST FLOW SHORTWAVE
TROUGH AND SYSTEM MOVE THROUGH THE REGION. PRECIPITATION CHANCES ARE
INCLUDED FOR THE SNOW ASPECT FOR THIS SYSTEM...WHICH COULD BE
ADVISORY WORTHY FOR SOME FLUFFY SNOW. THEN THE NEXT ARCTIC BLAST
FOLLOWS IN ITS WAKE FOR TUESDAY NIGHT AS A VERY DEEP TROUGH DROPS
INTO THE WESTERN GREAT LAKES. 925MB TEMPS PLUMMET FROM -14 TO -18C
AT 18Z TUESDAY TO AGAIN -26 TO -30C BY 12Z WEDNESDAY. WIND CHILL
ADVISORIES AND WARNINGS ARE LIKELY TO BE NEEDED. TEMPERATURES MAY
STRUGGLE TO CLIMB MUCH WEDNESDAY. LOWERED HIGHS SOME AND THESE MAY
NEED FURTHER LOWERING. ON A POSITIVE NOTE...MASSIVE WARM ADVECTION
IS PROGGED FOR WEDNESDAY NIGHT AND THURSDAY AS THE DEEP TROUGH MOVES
WELL OFF TO THE EAST. SO HIGHS SHOULD REBOUND NICELY FOR
THURSDAY...BUT STILL BELOW NORMAL.
INTERESTINGLY...THIS ARCTIC OUTBREAK FOR SUNDAY...MONDAY AND
WEDNESDAY ENDS UP BEING AT EXACTLY THE SAME TIME AS LAST YEARS
ARCTIC OUTBREAK. WIND CHILLS MAY NOT BE AS COLD...SINCE 925MB
TEMPS ARE A LITTLE WARMER THAN LAST YEARS ARCTIC OUTBREAK...BUT
ITS STILL LOOKS DANGEROUSLY COLD FOR SOME OF THIS TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1105 AM CST FRI JAN 2 2015
ROUGHLY 2500 FT CLOUD DECK HAS FINALLY CREPT ACROSS KRST LATE THIS
MORNING...BUT ITS EASTWARD PROGRESSED HAS SLOWED SIGNIFICANTLY.
TRENDS FAVOR THE 925 MB FLOW TO STEER THIS MVFR DECK MORE NORTHEAST
DURING THE AFTERNOON...SPARING KLSE FOR THE MOST PART. COULD STILL
SEE A PERIOD OF BKN CIGS LATER IN THE AFTERNOON...BUT CLOSER TO 3
KFT. ANTICIPATE THIS STRATUS TO LIFT NORTH OF BOTH KRST/KLSE BY MID
EVENING.
IFR/MVFR LOW CLOUDS WILL RETURN QUICKLY FROM THE SOUTH AFTER 06Z
TONIGHT THOUGH...WITH SOME ISENTROPIC UPGLIDE PROVIDING SOME LIFT IN
THE CLOUD LAYER. BUFKIT SOUNDINGS SUGGEST A POTENTIAL FOR ICE/NO ICE
IN THE CLOUDS...MAKING SNOW/FREEZING DRIZZLE POSSIBLE. THE PARENT
LOW PRESSURE SYSTEM IS WELL TO THE SOUTHEAST...AND EXPECT THE LIGHT
PCPN CHANCES TO AVOID KRST. WILL ADD A MENTION FOR -FZDZSN IN FOR
KLSE. ACCUMULATIONS OF EITHER PCPN TYPE LOOK MINOR. THE LOW CIGS
WILL HANG AROUND SAT...AND COULD SEE SOME MVFR REDUCTIONS IN VSBYS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
538 AM CST FRI JAN 2 2015
.UPDATE...
ISSUED AT 538 AM CST FRI JAN 2 2015
WATCHING A STRATUS DECK ADVECT EASTWARD ACROSS THE INTERSTATE 35
CORRIDOR OVER SOUTHERN MINNESOTA AND NORTH CENTRAL IOWA. THIS
DECK IS EXPECTED TO SPREAD INTO SOUTHEAST MINNESOTA AND NORTHEAST
IOWA THEN WE SHOULD SEE IT/S EASTWARD EXPANSION SLOW LATER THIS
MORNING AS 925 MB WINDS SWITCH FROM WESTERLY TO THE SOUTH. HAVE
INCREASED SKY COVER THROUGH LATE MORNING ALONG AND WEST OF THE
MISSISSIPPI RIVER TO ACOUNT FOR THIS EASTWARD EXPANSION IN CLOUD
COVER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 301 AM CST FRI JAN 2 2015
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A SHORTWAVE TROUGH OVER THE YUKON OF CANADA...A POTENT UPPER
TROUGH OVER NORTHERN BRITISH COLUMBIA...UPPER LOWS OVER ARIZONA AND
THE DENVER AREA...AND BROAD UPPER TROUGHING OVER EASTERN CANADA INTO
THE GREAT LAKES. WITH THE FORECAST AREA UNDER THE NORTHWEST FLOW ON
THE EDGE OF THIS UPPER TROUGHING...SUBSIDENCE AND DRYING HAS BEEN
OCCURRING. THIS HAS TRANSLATED INTO CLEARING SKIES IN THE WAKE OF A
SURFACE COLD FRONTAL PASSAGE DURING THE NIGHT. A BIT OF ARCTIC AIR
HAS BEEN SPILLING INTO NORTHERN WISCONSIN...NORTH OF HIGHWAY 29...
REFLECTED BY 925MB TEMPS DROPPING TO -12 TO -16C THERE AND SURFACE
TEMPERATURES IN THE SINGLE DIGITS ABOVE AND BELOW ZERO. READINGS ARE
MOSTLY IN THE TEENS ELSEWHERE IN THE FORECAST AREA. ONLY OTHER ITEM
OF NOTE WAS A LOOK AT PRECIPITABLE WATER VALUES FROM 00Z RAOBS. MOST
READINGS ACROSS THE CENTRAL/NORTHERN PLAINS AND OUR REGION WERE
BETWEEN 0.2 AND 0.35...FAIRLY DRY. HOWEVER...0.7-1 INCH VALUES WERE
PRESENT ACROSS THE SOUTHERN PLAINS AHEAD OF THE ARIZONA UPPER LOW.
MUCH OF THE SHORT TERM PERIOD IS QUIET THANKS TO THE DRY AIRMASS IN
PLACE REFLECTED BY 00Z RAOBS. HOWEVER...AS WE GET INTO THE AFTER
MIDNIGHT HOURS TONIGHT...THE 02.00Z GFS AND NAM SPREAD SOME LIGHT
QPF FROM THE SOUTH INTO CLAYTON/GRANT COUNTY AREA. THE 02.06Z
NAM/02.00Z ECMWF TAKE IT ONE STEP FURTHER AND SPREAD IT ALL THE WAY
THROUGH ABOUT THE EAST HALF OR MORE OF THE FORECAST AREA. MUCH OF
THIS QPF IS A RESULT OF AN ISENTROPIC LIFT / WARM ADVECTION REGIME
DEVELOPING DOWNSTREAM OF THE ARIZONA UPPER LOW...WHICH BY 12Z
SATURDAY IS PROGGED TO BE IN WEST TEXAS. ADDITIONALLY...WE HAVE THAT
UPPER LOW NEAR DENVER COMING THROUGH TO ADD IN SOME DPVA FORCING.
HAVE ADDED 20-40 PERCENT CHANCES INTO THE FORECAST FOR THIS FEATURE
AND THESE MAY NEED TO BE INCREASED LATER TODAY. MUCH OF THE LIFT IS
TAKING PLACE BETWEEN 10 KFT-15 KFT...BUT ENOUGH LOW LEVEL SATURATION
OCCURS TO ALLOW SNOW TO REACH THE SURFACE. IT SHOULD BE
NOTED...THOUGH...AS WE APPROACH 12Z THE ICE BEGINS TO EXITS THE
CLOUDS IN BOTH THE 02.00Z/06Z NAM AND GFS. SO...ANY LINGERING LIFT
APPROACHING THIS TIME COULD RESULT IN FREEZING DRIZZLE. HAVE ADDED
THIS POTENTIAL TO THE FORECAST. PROBABILITY FOR THIS FREEZING
DRIZZLE IS TOO LOW FOR AN ADVISORY AT THIS TIME.
WITH THE WARM ADVECTION REGIME DEVELOPING OVER THE NEXT 24 HOURS...
THE ARCTIC AIR TRYING TO SPILL INTO FAR NORTHERN SECTIONS OF THE
FORECAST AREA RIGHT NOW WILL STRUGGLE MAKING IT FARTHER SOUTH. IN
FACT...BY 00Z THIS EVENING...925MB TEMPS ALREADY ARE PROGGED FROM
-5C SOUTHWEST TO -9C NORTHEAST. WITH WHAT SHOULD BE A MOSTLY SUNNY
DAY...ANTICIPATE HIGHS CAN TOP OUT IN THE TEENS OVER TAYLOR/CLARK
COUNTIES TO THE 20S OVER THE REST OF THE SNOW PACK AREAS...AND LOW
30Z OVER SNOW FREE AREAS. WARM ADVECTION PERSISTS TONIGHT...WHICH
WITH CLOUDS INCREASING OVERNIGHT SHOULD HELP SOMEWHAT ON
TEMPERATURES. HOWEVER...WITH A MOSTLY CLEAR EVENING AND A WEAK
GRADIENT...READINGS COULD DROP INTO THE SINGLE DIGITS OVER
TAYLOR/CLARK TO THE TEENS TO LOW 20S ELSEWHERE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 301 AM CST FRI JAN 2 2015
THE FOCUS FOR SATURDAY AND SATURDAY NIGHT CONTINUES TO REVOLVE
AROUND THE CURRENT UPPER LOW IN ARIZONA AND THE SHORTWAVE TROUGH
OVER BRITISH COLUMBIA. IT APPEARS THE MAIN ROLE OF THE BRITISH
COLUMBIA SHORTWAVE IS TO SERVE AS A KICKER FOR THE UPPER LOW. GOOD
MODEL CONSENSUS EXISTS FOR THE UPPER LOW TO TRACK THROUGH THE
DAVENPORT IA AREA AROUND 06Z SUNDAY AND INTO LOWER MICHIGAN BY 12Z
SUNDAY. HOWEVER...THE BRITISH COLUMBIA TROUGH DOES SPLIT APART WITH
A SHORTWAVE THAT COMES OFF IT WHICH MODELS BRING THROUGH THE
FORECAST AREA SATURDAY NIGHT. THAT SHORTWAVE EVENTUALLY PHASES WITH
THE UPPER LOW OVER LOWER MICHIGAN...RESULTING IN A DEEPENING SURFACE
LOW WELL OFF TO OUR EAST.
THE ISENTROPIC LIFT REGIME THAT DEVELOPED TONIGHT LOOKS TO PERSIST
THROUGH SATURDAY...THOUGH MAINLY FOCUSED OVER THE SOUTHEAST 1/3 TO
1/2 OF THE FORECAST AREA. THUS...THIS IS WHERE THE MAIN FOCUS FOR
PRECIPITATION EXISTS. AGAIN...BOTH THE 02.00Z NAM AND GFS POINT TO
WAVES OF ICE IN AND OUT OF THE CLOUDS...THUS THE FORECAST INCLUDES A
MENTION OF BOTH SNOW AND DRIZZLE/FREEZING DRIZZLE. WITH A GREATER
CHANCE FOR PRECIPITATION...MAY NEED AN ADVISORY FOR THIS WINTRY MIX
ASPECT. BEING DURING THE DAYTIME AND TEMPERATURES PERHAPS CLIMBING
ABOVE THE FREEZING MARK...THIS SHOULD HELP LIMIT ICE ACCUMULATION.
PRECIPITATION CHANCES INCREASE ACROSS THE ENTIRE FORECAST AREA
SATURDAY NIGHT WITH THE CROSSING OF THE SHORTWAVE AND BRUSH BY FROM
THE UPPER LOW. THE DEFORMATION SNOW BAND ACCOMPANYING THE NORTHWEST
SIDE OF THE DEEPENING SURFACE LOW MAY CLIP THE SOUTHEAST 1/3 OF THE
FORECAST AREA...THUS HIGHEST PRECIPITATION CHANCES AND QPF ARE
CONFINED THERE. PRECIPITATION SHOULD DIMINISH WEST TO EAST QUICKLY
LATE IN THE NIGHT AS SUBSIDENCE AND MUCH COLDER AND DRIER AIR ADVECT
IN. SNOWFALL AMOUNTS OVERALL HAVE COME DOWN QUITE A BIT WITH THE
02.00Z CYCLE...INCLUDING WITH THE 02.00Z ECMWF. THIS DECLINE IS A
COMBINATION OF THE AFOREMENTIONED WINTRY MIX AND MODELS NOT NEARLY
AS IMPRESSIVE WITH THE DEFORMATION BAND. IT SHOULD BE NOTED THAT THE
02.06Z NAM AND TO SOME DEGREE THE 02.00Z ECMWF HAVE THE DEFORMATION
BAND MISS MUCH OF THE FORECAST AREA...WITH MUCH OF THE PRECIP FOCUS
ON THE SNOW ACCOMPANYING THE SHORTWAVE. IF THIS HAPPENS...EVEN LESS
SNOW WILL FALL OVER THE SOUTHEAST 1/2 OF THE AREA.
FOCUS FOR THE REST OF THE FORECAST TURNS TO ARCTIC AIR. WE HAVE TWO
BIG BLASTS TO CONTEND WITH...THE FIRST COMING IN LATE SATURDAY NIGHT
AND THE SECOND COMING IN TUESDAY NIGHT. BOTH BLASTS HAVE A 35-45 KT
925MB WINDS CORE COMING ACROSS...WHICH MEANS THERE IS POTENTIAL WIND
SPEEDS COULD TRY TO APPROACH ADVISORY CRITERIA. HOWEVER...THE ARCTIC
AIR ACCOMPANYING THE WIND WILL FORCE WIND CHILL AS THE BIGGER
HAZARD. HOW COLD WE GET WILL DEPEND SOMEWHAT ON HOW MUCH SNOW WE GET
OVER THE NEXT FEW DAYS GIVEN THE LACK OF SNOW OVER THE SOUTHEAST
HALF OF THE FORECAST AREA. DETAILS...925MB TEMPS FALL FROM -4 TO -9C
AT 06Z SUNDAY TO -23 TO -26C BY 00Z MONDAY AND -26 TO -30C BY 12Z
MONDAY...WHICH MEANS TEMPERATURES SHOULD JUST FALL THROUGH THE DAY
SUNDAY...WITH MUCH OF THE NORTHWEST HALF BELOW ZERO FOR MUCH OF THE
DAY. WIND CHILL ADVISORIES LOOK LIKELY FOR THE NORTHWEST HALF ON
SUNDAY...EXPANDING EVERYWHERE SUNDAY NIGHT INTO MONDAY WITH MAYBE
SOME WARNINGS FOR TAYLOR/CLARK AND SOUTHEAST MN. THERE IS A BRIEF
WARM UP FOR MONDAY NIGHT INTO TUESDAY AS A NORTHWEST FLOW SHORTWAVE
TROUGH AND SYSTEM MOVE THROUGH THE REGION. PRECIPITATION CHANCES ARE
INCLUDED FOR THE SNOW ASPECT FOR THIS SYSTEM...WHICH COULD BE
ADVISORY WORTHY FOR SOME FLUFFY SNOW. THEN THE NEXT ARCTIC BLAST
FOLLOWS IN ITS WAKE FOR TUESDAY NIGHT AS A VERY DEEP TROUGH DROPS
INTO THE WESTERN GREAT LAKES. 925MB TEMPS PLUMMET FROM -14 TO -18C
AT 18Z TUESDAY TO AGAIN -26 TO -30C BY 12Z WEDNESDAY. WIND CHILL
ADVISORIES AND WARNINGS ARE LIKELY TO BE NEEDED. TEMPERATURES MAY
STRUGGLE TO CLIMB MUCH WEDNESDAY. LOWERED HIGHS SOME AND THESE MAY
NEED FURTHER LOWERING. ON A POSITIVE NOTE...MASSIVE WARM ADVECTION
IS PROGGED FOR WEDNESDAY NIGHT AND THURSDAY AS THE DEEP TROUGH MOVES
WELL OFF TO THE EAST. SO HIGHS SHOULD REBOUND NICELY FOR
THURSDAY...BUT STILL BELOW NORMAL.
INTERESTINGLY...THIS ARCTIC OUTBREAK FOR SUNDAY...MONDAY AND
WEDNESDAY ENDS UP BEING AT EXACTLY THE SAME TIME AS LAST YEARS
ARCTIC OUTBREAK. WIND CHILLS MAY NOT BE AS COLD...SINCE 925MB
TEMPS ARE A LITTLE WARMER THAN LAST YEARS ARCTIC OUTBREAK...BUT
ITS STILL LOOKS DANGEROUSLY COLD FOR SOME OF THIS TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 538 AM CST FRI JAN 2 2015
AN MVFR STRATUS DECK WILL MOVE ACROSS THE TAF SITES THIS MORNING
BUT SHOULD THEN SHIFT NORTH AS 925 MB WINDS BECOME SOUTHERLY. PLAN
ON MVFR CONDITIONS AT TIMES THIS MORNING IN THE STRATUS THEN WE
SHOULD SEE CONDITIONS IMPROVE TO VFR. MVFR/IFR CONDITIONS ARE
EXPECTED TONIGHT AS LOW PRESSURE APPROACHES THE REGION AND LOW
LEVEL MOISTURE INCREASES. PLAN ON CEILINGS LOWERING TO 700 FT AT
KRST AROUND 10Z AND CEILINGS LOWERING TO 2000 FT AT KLSE AROUND
06Z. THERE MAY ALSO BE SOME VISIBILITY RESTRICTIONS IN FOG LATER
TONIGHT BUT CONFIDENCE IS LOW ON THE FOG IMPACTING THE TAF SITES.
THE MAIN IMPACT WILL BE FROM THE LOW STRATUS PRODUCING IFR
CONDITIONS AT TIMES...MAINLY AT KRST. THE IFR STRATUS MAY ALSO
IMPACT KLSE AFTER 09Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...WETENKAMP
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
301 AM CST FRI JAN 2 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 301 AM CST FRI JAN 2 2015
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A SHORTWAVE TROUGH OVER THE YUKON OF CANADA...A POTENT UPPER
TROUGH OVER NORTHERN BRITISH COLUMBIA...UPPER LOWS OVER ARIZONA AND
THE DENVER AREA...AND BROAD UPPER TROUGHING OVER EASTERN CANADA INTO
THE GREAT LAKES. WITH THE FORECAST AREA UNDER THE NORTHWEST FLOW ON
THE EDGE OF THIS UPPER TROUGHING...SUBSIDENCE AND DRYING HAS BEEN
OCCURRING. THIS HAS TRANSLATED INTO CLEARING SKIES IN THE WAKE OF A
SURFACE COLD FRONTAL PASSAGE DURING THE NIGHT. A BIT OF ARCTIC AIR
HAS BEEN SPILLING INTO NORTHERN WISCONSIN...NORTH OF HIGHWAY 29...
REFLECTED BY 925MB TEMPS DROPPING TO -12 TO -16C THERE AND SURFACE
TEMPERATURES IN THE SINGLE DIGITS ABOVE AND BELOW ZERO. READINGS ARE
MOSTLY IN THE TEENS ELSEWHERE IN THE FORECAST AREA. ONLY OTHER ITEM
OF NOTE WAS A LOOK AT PRECIPITABLE WATER VALUES FROM 00Z RAOBS. MOST
READINGS ACROSS THE CENTRAL/NORTHERN PLAINS AND OUR REGION WERE
BETWEEN 0.2 AND 0.35...FAIRLY DRY. HOWEVER...0.7-1 INCH VALUES WERE
PRESENT ACROSS THE SOUTHERN PLAINS AHEAD OF THE ARIZONA UPPER LOW.
MUCH OF THE SHORT TERM PERIOD IS QUIET THANKS TO THE DRY AIRMASS IN
PLACE REFLECTED BY 00Z RAOBS. HOWEVER...AS WE GET INTO THE AFTER
MIDNIGHT HOURS TONIGHT...THE 02.00Z GFS AND NAM SPREAD SOME LIGHT
QPF FROM THE SOUTH INTO CLAYTON/GRANT COUNTY AREA. THE 02.06Z
NAM/02.00Z ECMWF TAKE IT ONE STEP FURTHER AND SPREAD IT ALL THE WAY
THROUGH ABOUT THE EAST HALF OR MORE OF THE FORECAST AREA. MUCH OF
THIS QPF IS A RESULT OF AN ISENTROPIC LIFT / WARM ADVECTION REGIME
DEVELOPING DOWNSTREAM OF THE ARIZONA UPPER LOW...WHICH BY 12Z
SATURDAY IS PROGGED TO BE IN WEST TEXAS. ADDITIONALLY...WE HAVE THAT
UPPER LOW NEAR DENVER COMING THROUGH TO ADD IN SOME DPVA FORCING.
HAVE ADDED 20-40 PERCENT CHANCES INTO THE FORECAST FOR THIS FEATURE
AND THESE MAY NEED TO BE INCREASED LATER TODAY. MUCH OF THE LIFT IS
TAKING PLACE BETWEEN 10 KFT-15 KFT...BUT ENOUGH LOW LEVEL SATURATION
OCCURS TO ALLOW SNOW TO REACH THE SURFACE. IT SHOULD BE
NOTED...THOUGH...AS WE APPROACH 12Z THE ICE BEGINS TO EXITS THE
CLOUDS IN BOTH THE 02.00Z/06Z NAM AND GFS. SO...ANY LINGERING LIFT
APPROACHING THIS TIME COULD RESULT IN FREEZING DRIZZLE. HAVE ADDED
THIS POTENTIAL TO THE FORECAST. PROBABILITY FOR THIS FREEZING
DRIZZLE IS TOO LOW FOR AN ADVISORY AT THIS TIME.
WITH THE WARM ADVECTION REGIME DEVELOPING OVER THE NEXT 24 HOURS...
THE ARCTIC AIR TRYING TO SPILL INTO FAR NORTHERN SECTIONS OF THE
FORECAST AREA RIGHT NOW WILL STRUGGLE MAKING IT FARTHER SOUTH. IN
FACT...BY 00Z THIS EVENING...925MB TEMPS ALREADY ARE PROGGED FROM
-5C SOUTHWEST TO -9C NORTHEAST. WITH WHAT SHOULD BE A MOSTLY SUNNY
DAY...ANTICIPATE HIGHS CAN TOP OUT IN THE TEENS OVER TAYLOR/CLARK
COUNTIES TO THE 20S OVER THE REST OF THE SNOW PACK AREAS...AND LOW
30Z OVER SNOW FREE AREAS. WARM ADVECTION PERSISTS TONIGHT...WHICH
WITH CLOUDS INCREASING OVERNIGHT SHOULD HELP SOMEWHAT ON
TEMPERATURES. HOWEVER...WITH A MOSTLY CLEAR EVENING AND A WEAK
GRADIENT...READINGS COULD DROP INTO THE SINGLE DIGITS OVER
TAYLOR/CLARK TO THE TEENS TO LOW 20S ELSEWHERE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 301 AM CST FRI JAN 2 2015
THE FOCUS FOR SATURDAY AND SATURDAY NIGHT CONTINUES TO REVOLVE
AROUND THE CURRENT UPPER LOW IN ARIZONA AND THE SHORTWAVE TROUGH
OVER BRITISH COLUMBIA. IT APPEARS THE MAIN ROLE OF THE BRITISH
COLUMBIA SHORTWAVE IS TO SERVE AS A KICKER FOR THE UPPER LOW. GOOD
MODEL CONSENSUS EXISTS FOR THE UPPER LOW TO TRACK THROUGH THE
DAVENPORT IA AREA AROUND 06Z SUNDAY AND INTO LOWER MICHIGAN BY 12Z
SUNDAY. HOWEVER...THE BRITISH COLUMBIA TROUGH DOES SPLIT APART WITH
A SHORTWAVE THAT COMES OFF IT WHICH MODELS BRING THROUGH THE
FORECAST AREA SATURDAY NIGHT. THAT SHORTWAVE EVENTUALLY PHASES WITH
THE UPPER LOW OVER LOWER MICHIGAN...RESULTING IN A DEEPENING SURFACE
LOW WELL OFF TO OUR EAST.
THE ISENTROPIC LIFT REGIME THAT DEVELOPED TONIGHT LOOKS TO PERSIST
THROUGH SATURDAY...THOUGH MAINLY FOCUSED OVER THE SOUTHEAST 1/3 TO
1/2 OF THE FORECAST AREA. THUS...THIS IS WHERE THE MAIN FOCUS FOR
PRECIPITATION EXISTS. AGAIN...BOTH THE 02.00Z NAM AND GFS POINT TO
WAVES OF ICE IN AND OUT OF THE CLOUDS...THUS THE FORECAST INCLUDES A
MENTION OF BOTH SNOW AND DRIZZLE/FREEZING DRIZZLE. WITH A GREATER
CHANCE FOR PRECIPITATION...MAY NEED AN ADVISORY FOR THIS WINTRY MIX
ASPECT. BEING DURING THE DAYTIME AND TEMPERATURES PERHAPS CLIMBING
ABOVE THE FREEZING MARK...THIS SHOULD HELP LIMIT ICE ACCUMULATION.
PRECIPITATION CHANCES INCREASE ACROSS THE ENTIRE FORECAST AREA
SATURDAY NIGHT WITH THE CROSSING OF THE SHORTWAVE AND BRUSH BY FROM
THE UPPER LOW. THE DEFORMATION SNOW BAND ACCOMPANYING THE NORTHWEST
SIDE OF THE DEEPENING SURFACE LOW MAY CLIP THE SOUTHEAST 1/3 OF THE
FORECAST AREA...THUS HIGHEST PRECIPITATION CHANCES AND QPF ARE
CONFINED THERE. PRECIPITATION SHOULD DIMINISH WEST TO EAST QUICKLY
LATE IN THE NIGHT AS SUBSIDENCE AND MUCH COLDER AND DRIER AIR ADVECT
IN. SNOWFALL AMOUNTS OVERALL HAVE COME DOWN QUITE A BIT WITH THE
02.00Z CYCLE...INCLUDING WITH THE 02.00Z ECMWF. THIS DECLINE IS A
COMBINATION OF THE AFOREMENTIONED WINTRY MIX AND MODELS NOT NEARLY
AS IMPRESSIVE WITH THE DEFORMATION BAND. IT SHOULD BE NOTED THAT THE
02.06Z NAM AND TO SOME DEGREE THE 02.00Z ECMWF HAVE THE DEFORMATION
BAND MISS MUCH OF THE FORECAST AREA...WITH MUCH OF THE PRECIP FOCUS
ON THE SNOW ACCOMPANYING THE SHORTWAVE. IF THIS HAPPENS...EVEN LESS
SNOW WILL FALL OVER THE SOUTHEAST 1/2 OF THE AREA.
FOCUS FOR THE REST OF THE FORECAST TURNS TO ARCTIC AIR. WE HAVE TWO
BIG BLASTS TO CONTEND WITH...THE FIRST COMING IN LATE SATURDAY NIGHT
AND THE SECOND COMING IN TUESDAY NIGHT. BOTH BLASTS HAVE A 35-45 KT
925MB WINDS CORE COMING ACROSS...WHICH MEANS THERE IS POTENTIAL WIND
SPEEDS COULD TRY TO APPROACH ADVISORY CRITERIA. HOWEVER...THE ARCTIC
AIR ACCOMPANYING THE WIND WILL FORCE WIND CHILL AS THE BIGGER
HAZARD. HOW COLD WE GET WILL DEPEND SOMEWHAT ON HOW MUCH SNOW WE GET
OVER THE NEXT FEW DAYS GIVEN THE LACK OF SNOW OVER THE SOUTHEAST
HALF OF THE FORECAST AREA. DETAILS...925MB TEMPS FALL FROM -4 TO -9C
AT 06Z SUNDAY TO -23 TO -26C BY 00Z MONDAY AND -26 TO -30C BY 12Z
MONDAY...WHICH MEANS TEMPERATURES SHOULD JUST FALL THROUGH THE DAY
SUNDAY...WITH MUCH OF THE NORTHWEST HALF BELOW ZERO FOR MUCH OF THE
DAY. WIND CHILL ADVISORIES LOOK LIKELY FOR THE NORTHWEST HALF ON
SUNDAY...EXPANDING EVERYWHERE SUNDAY NIGHT INTO MONDAY WITH MAYBE
SOME WARNINGS FOR TAYLOR/CLARK AND SOUTHEAST MN. THERE IS A BRIEF
WARM UP FOR MONDAY NIGHT INTO TUESDAY AS A NORTHWEST FLOW SHORTWAVE
TROUGH AND SYSTEM MOVE THROUGH THE REGION. PRECIPITATION CHANCES ARE
INCLUDED FOR THE SNOW ASPECT FOR THIS SYSTEM...WHICH COULD BE
ADVISORY WORTHY FOR SOME FLUFFY SNOW. THEN THE NEXT ARCTIC BLAST
FOLLOWS IN ITS WAKE FOR TUESDAY NIGHT AS A VERY DEEP TROUGH DROPS
INTO THE WESTERN GREAT LAKES. 925MB TEMPS PLUMMET FROM -14 TO -18C
AT 18Z TUESDAY TO AGAIN -26 TO -30C BY 12Z WEDNESDAY. WIND CHILL
ADVISORIES AND WARNINGS ARE LIKELY TO BE NEEDED. TEMPERATURES MAY
STRUGGLE TO CLIMB MUCH WEDNESDAY. LOWERED HIGHS SOME AND THESE MAY
NEED FURTHER LOWERING. ON A POSITIVE NOTE...MASSIVE WARM ADVECTION
IS PROGGED FOR WEDNESDAY NIGHT AND THURSDAY AS THE DEEP TROUGH MOVES
WELL OFF TO THE EAST. SO HIGHS SHOULD REBOUND NICELY FOR
THURSDAY...BUT STILL BELOW NORMAL.
INTERESTINGLY...THIS ARCTIC OUTBREAK FOR SUNDAY...MONDAY AND
WEDNESDAY ENDS UP BEING AT EXACTLY THE SAME TIME AS LAST YEARS
ARCTIC OUTBREAK. WIND CHILLS MAY NOT BE AS COLD...SINCE 925MB
TEMPS ARE A LITTLE WARMER THAN LAST YEARS ARCTIC OUTBREAK...BUT
ITS STILL LOOKS DANGEROUSLY COLD FOR SOME OF THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1113 PM CST THU JAN 1 2015
THE BAND OF MVFR/VFR CLOUDS HAS BEEN SLOWER THAN EXPECTED TO SLIP
SOUTH OF THE AREA...BUT THE BACK EDGE IS GETTING VERY CLOSE TO
BOTH TAF SITES AND EXPECTING THESE CLOUDS TO MOVE OUT OVERNIGHT.
AFTER THAT...VFR CONDITIONS AS HIGH PRESSURE SLIDES SOUTHEAST
ACROSS THE REGION WITH THE WINDS COMING AROUND TO THE SOUTH FRIDAY
MORNING. MOISTURE RETURNING TO THE AREA ON THE BACK SIDE OF THE
HIGH COULD RESULT IN THE DEVELOPMENT OF SOME MVFR CEILINGS...BUT
THIS IS NOT EXPECTED TO OCCUR UNTIL AFTER 03.06Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1157 PM MST THU JAN 1 2015
.UPDATE...
ISSUED AT 911 PM MST THU JAN 1 2015
SNOWING MORE STEADILY TO OUR SOUTH IN NORTHERN COLORADO BETWEEN
CHEYENNE AND FORT MORGAN ON THE NORTHERN SIDE OF A WEAK MIDLEVEL
CIRCULATION. THE SNOWBAND IS HAVING A REALLY HARD TIME WORKING
ITS WAY NORTH TO THE WYOMING BORDER GIVEN DEEPER DRY AIR OVER OUR
AREA. LATEST HRRR AND NAM MODELS INDICATING SOME ENHANCEMENT OF
LIGHT SNOW SHOWERS OVER OUR AREA AFTER MIDNIGHT...LASTING ONLY
THROUGH ABOUT 5 AM. THE LATEST NAM IS THE HEAVIEST WITH
ACCUMULATIONS INDICATING POSSIBLY A FEW INCHES OVER SOUTHEAST
WYOMING BY DAYBREAK...WITH THE HRRR SHOWING LESSER AMOUNTS. THE
LATEST 00Z GFS SHOWS LITTLE TO ANY QPF OR SNOWFALL ACCUMULATION
OVER OUR AREA KEEPING MOST IF ANY ACCUMULATION TO OUR SOUTH
THROUGH MORNING CLOSER TO THE MIDLEVEL CIRCULATION. WE ARE SEEING
SOME INCREASE IN LIGHT RADAR REFLECTIVITY AROUND WHEATLAND AND
CHUGWATER...BUT UNDERNEATH THE STRONGER RETURNS OF 15 TO 25 DBZ
SPOTTERS ARE CURRENTLY REPORTING NO SNOW FALLING. THERE MAY BE A
FEW FLURRIES OCCURRING RIGHT NOW ALONG I-25 BETWEEN CHEYENNE AND
CHUGWATER...BUT NOTHING SIGNIFICANT.
WE UPDATED ZONES TO INCLUDE ISOLATED LIGHT SNOW SHOWERS ACROSS
THE SOUTHEASTERN QUARTER OF OUR FORECAST AREA LATE TONIGHT WITH
LITTLE ADDITIONAL SNOW ACCUMULATION EXPECTED. IF THE NAM PANS OUT
TO BE MORE CORRECT (AND WE SUSPECT IT IS OVERDOING THE SNOWFALL
COVERAGE AND INTENSITY LATE TONIGHT)...THEN AN UPDATE TO INCREASE
COVERAGE MAY BE NECESSARY (WE WILL KEEP AN EYE ON IT). BOTTOM LINE
RIGHT NOW...WE THINK ANY ACCUMULATION WE GET ANYWHERE IN OUR AREA
TONIGHT WILL BE FAIRLY LIGHT (MOSTLY A VERY LIGHT DUSTING) IF ANY
BASED ON WHAT WE ARE SEEING AT THIS TIME. JG
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 300 PM MST THU JAN 1 2015
QUIET WEATHER THIS AFTERNOON BUT CLOUDS CONVERGING FROM NORTH AND
SOUTH AS THE CWA LIES BETWEEN TWO STREAMFLOWS. EXPECT CLOUDS TO
CONTINUE INCREASING OVER THE CWA THROUGH THIS EVENING. MEANWHILE
MODELS CONTINUE TO ADVERTISE A PIECE OF ENERGY BREAKING OFF FROM
THE UPPER LOW NEAR THE FOUR-CORNERS AREA AND DEVELOPING A SECOND
UPPER LOW OVER NORTHEAST COLORADO OVERNIGHT. VISIBLE SATELLITE
SEEMS TO HINT THAT THIS IS HAPPENING. WILL CONTINUE TO MENTION SOME
FLURRIES OVER PARTS OF THE CWA TONIGHT AS THE NEW UPPER LOW DRIFTS
SLOWLY NORTHEAST TONIGHT AND FRIDAY BUT DRY AIRMASS WILL LIMIT
SNOWFALL. TEMPS NOT AS COLD TONIGHT WITH MORE CLOUDCOVER. A QUIET
DAY FOR FRIDAY WITH A SHORT UPPER RIDGE PASSING BY.
ATTENTION WILL THEN TURN TO CLIPPER-LIKE SYSTEM THAT WILL MOVE
SOUTHEAST INTO THE NORTHERN HIGH PLAINS BY SAT MORNING WITH AN
ACCOMPANYING COLD FRONT THAT WILL THEN PASS ACROSS THE CWA SAT
MORNING. EXPECT TO SEE A PERIOD OF LIGHT SNOWS BEHIND THIS FRONT
GIVEN UPSLOPE FLOW AND SOME UPPER SUPPORT. DURATION OF SNOW NOT
LONG THUS AMOUNTS SHOULD STAY LIGHT. TEMPS LIKELY STEADY TO SLOWLY
FALLING SATURDAY AFTERNOON BEHIND THE FRONT WITH SNOW ENDING BY
EVENING EXCEPT OVER THE HIGHER MTNS WHERE SOME SNOW SHOWERS SHOULD
HANG ON THROUGH SAT NIGHT. DECENT MID-LEVEL WINDS SHOULD MIX DOWN
SATURDAY RESULTING IN QUITE BREEZY CONDITIONS OVER THE PLAINS.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 300 PM MST THU JAN 1 2015
SHORTWAVE IN NORTHWESTERLY FLOW ALOFT WILL SLIDE SOUTHEASTWARD FROM
MONTANA INTO THE DAKOTAS ON SUN. THIS WILL CAUSE A WEAK FRONT TO
BACK ACROSS AREAS TO THE EAST OF THE LARAMIE RANGE FOR A
CONTINUATION OF BELOW NORMAL TEMPS. WITH THE SFC TROUGH DRAPED
ACROSS THE ARLINGTON AREA...WILL SEE GUSTY WEST TO SOUTHWEST WINDS
FROM LARAMIE TO RAWLINS DURING THE AFTERNOON. THE 12Z ECMWF IS MORE
IN LINE WITH THE DRIER GFS BEHIND THE FROPA...HOWEVER STILL HAVE
SLIGHT CHANCE POPS OVER THE PLAINS THROUGH SUN NIGHT.
THE MODELS HAVE DELAYED THE INCREASE IN LLVL GRADIENT ACROSS
SOUTHEAST WY UNTIL MON. THE GFS SHOWS THE 850MB CAG-CPR GRADIENT
RISING TO 75-80 METERS BY MON AFTN WITH A SFC LOW OVER NORTHEAST WY.
IN ADDITION...SUBSIDENCE IN THE RIGHT EXIT REGION OF THE UPPER
JET MOVES OVERHEAD. THUS...IT LOOKS LIKE THE TIME PERIOD FROM
MIDDAY MON THROUGH MON NIGHT WILL BE FAVORED FOR HIGH WINDS IN THE
WIND PRONE AREAS AND PERHAPS SPREADING OVER PORTIONS OF THE
ADJACENT PLAINS IN SOUTHEAST WY. TEMPS WILL RISE AROUND 10 DEGREES
BUT STILL BE AVERAGE FOR EARLY JAN. WINDS WILL COME DOWN BY MON
NIGHT INTO TUES AS HIGHER PRESSURES MOVE INTO THE NORTHERN HIGH
PLAINS. TEMPS TRY TO MODERATE SOME BY TUES AND WED...MOST NOTABLY
OVER SOUTHEAST WY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1153 PM MST THU JAN 1 2015
VFR...WITH LOCALIZED MVFR IN SNOW SHOWERS THROUGH 12Z.
&&
.FIRE WEATHER...
ISSUED AT 300 PM MST THU JAN 1 2015
SEE NO REAL CONCERNS INTO AT LEAST EARLY NEXT WEEK WITH COOL
TEMPERATURES AND SNOW COVER. WINDS LOOK TO BECOME GUSTY OVER THE
PLAINS SATURDAY THEN BECOME GUSTY SUNDAY INTO MONDAY AROUND THE SE
WYOMING MTNS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...JG
SHORT TERM...RE
LONG TERM...ZF
AVIATION...RUBIN
FIRE WEATHER...RE
AREA FORECAST DISCUSSION...UPDATED
NWS CHEYENNE WY
911 PM MST THU JAN 1 2015
.UPDATE...
ISSUED AT 911 PM MST THU JAN 1 2015
SNOWING MORE STEADILY TO OUR SOUTH IN NORTHERN COLORADO BETWEEN
CHEYENNE AND FORT MORGAN ON THE NORTHERN SIDE OF A WEAK MIDLEVEL
CIRCULATION. THE SNOWBAND IS HAVING A REALLY HARD TIME WORKING
ITS WAY NORTH TO THE WYOMING BORDER GIVEN DEEPER DRY AIR OVER OUR
AREA. LATEST HRRR AND NAM MODELS INDICATING SOME ENHANCEMENT OF
LIGHT SNOW SHOWERS OVER OUR AREA AFTER MIDNIGHT...LASTING ONLY
THROUGH ABOUT 5 AM. THE LATEST NAM IS THE HEAVIEST WITH
ACCUMULATIONS INDICATING POSSIBLY A FEW INCHES OVER SOUTHEAST
WYOMING BY DAYBREAK...WITH THE HRRR SHOWING LESSER AMOUNTS. THE
LATEST 00Z GFS SHOWS LITTLE TO ANY QPF OR SNOWFALL ACCUMULATION
OVER OUR AREA KEEPING MOST IF ANY ACCUMULATION TO OUR SOUTH
THROUGH MORNING CLOSER TO THE MIDLEVEL CIRCULATION. WE ARE SEEING
SOME INCREASE IN LIGHT RADAR REFLECTIVITY AROUND WHEATLAND AND
CHUGWATER...BUT UNDERNEATH THE STRONGER RETURNS OF 15 TO 25 DBZ
SPOTTERS ARE CURRENTLY REPORTING NO SNOW FALLING. THERE MAY BE A
FEW FLURRIES OCCURRING RIGHT NOW ALONG I-25 BETWEEN CHEYENNE AND
CHUGWATER...BUT NOTHING SIGNIFICANT.
WE UPDATED ZONES TO INCLUDE ISOLATED LIGHT SNOW SHOWERS ACROSS
THE SOUTHEASTERN QUARTER OF OUR FORECAST AREA LATE TONIGHT WITH
LITTLE ADDITIONAL SNOW ACCUMULATION EXPECTED. IF THE NAM PANS OUT
TO BE MORE CORRECT (AND WE SUSPECT IT IS OVERDOING THE SNOWFALL
COVERAGE AND INTENSITY LATE TONIGHT)...THEN AN UPDATE TO INCREASE
COVERAGE MAY BE NECESSARY (WE WILL KEEP AN EYE ON IT). BOTTOM LINE
RIGHT NOW...WE THINK ANY ACCUMULATION WE GET ANYWHERE IN OUR AREA
TONIGHT WILL BE FAIRLY LIGHT (MOSTLY A VERY LIGHT DUSTING) IF ANY
BASED ON WHAT WE ARE SEEING AT THIS TIME. JG
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 300 PM MST THU JAN 1 2015
QUIET WEATHER THIS AFTERNOON BUT CLOUDS CONVERGING FROM NORTH AND
SOUTH AS THE CWA LIES BETWEEN TWO STREAMFLOWS. EXPECT CLOUDS TO
CONTINUE INCREASING OVER THE CWA THROUGH THIS EVENING. MEANWHILE
MODELS CONTINUE TO ADVERTISE A PIECE OF ENERGY BREAKING OFF FROM
THE UPPER LOW NEAR THE FOUR-CORNERS AREA AND DEVELOPING A SECOND
UPPER LOW OVER NORTHEAST COLORADO OVERNIGHT. VISIBLE SATELLITE
SEEMS TO HINT THAT THIS IS HAPPENING. WILL CONTINUE TO MENTION SOME
FLURRIES OVER PARTS OF THE CWA TONIGHT AS THE NEW UPPER LOW DRIFTS
SLOWLY NORTHEAST TONIGHT AND FRIDAY BUT DRY AIRMASS WILL LIMIT
SNOWFALL. TEMPS NOT AS COLD TONIGHT WITH MORE CLOUDCOVER. A QUIET
DAY FOR FRIDAY WITH A SHORT UPPER RIDGE PASSING BY.
ATTENTION WILL THEN TURN TO CLIPPER-LIKE SYSTEM THAT WILL MOVE
SOUTHEAST INTO THE NORTHERN HIGH PLAINS BY SAT MORNING WITH AN
ACCOMPANYING COLD FRONT THAT WILL THEN PASS ACROSS THE CWA SAT
MORNING. EXPECT TO SEE A PERIOD OF LIGHT SNOWS BEHIND THIS FRONT
GIVEN UPSLOPE FLOW AND SOME UPPER SUPPORT. DURATION OF SNOW NOT
LONG THUS AMOUNTS SHOULD STAY LIGHT. TEMPS LIKELY STEADY TO SLOWLY
FALLING SATURDAY AFTERNOON BEHIND THE FRONT WITH SNOW ENDING BY
EVENING EXCEPT OVER THE HIGHER MTNS WHERE SOME SNOW SHOWERS SHOULD
HANG ON THROUGH SAT NIGHT. DECENT MID-LEVEL WINDS SHOULD MIX DOWN
SATURDAY RESULTING IN QUITE BREEZY CONDITIONS OVER THE PLAINS.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 300 PM MST THU JAN 1 2015
SHORTWAVE IN NORTHWESTERLY FLOW ALOFT WILL SLIDE SOUTHEASTWARD FROM
MONTANA INTO THE DAKOTAS ON SUN. THIS WILL CAUSE A WEAK FRONT TO
BACK ACROSS AREAS TO THE EAST OF THE LARAMIE RANGE FOR A
CONTINUATION OF BELOW NORMAL TEMPS. WITH THE SFC TROUGH DRAPED
ACROSS THE ARLINGTON AREA...WILL SEE GUSTY WEST TO SOUTHWEST WINDS
FROM LARAMIE TO RAWLINS DURING THE AFTERNOON. THE 12Z ECMWF IS MORE
IN LINE WITH THE DRIER GFS BEHIND THE FROPA...HOWEVER STILL HAVE
SLIGHT CHANCE POPS OVER THE PLAINS THROUGH SUN NIGHT.
THE MODELS HAVE DELAYED THE INCREASE IN LLVL GRADIENT ACROSS
SOUTHEAST WY UNTIL MON. THE GFS SHOWS THE 850MB CAG-CPR GRADIENT
RISING TO 75-80 METERS BY MON AFTN WITH A SFC LOW OVER NORTHEAST WY.
IN ADDITION...SUBSIDENCE IN THE RIGHT EXIT REGION OF THE UPPER
JET MOVES OVERHEAD. THUS...IT LOOKS LIKE THE TIME PERIOD FROM
MIDDAY MON THROUGH MON NIGHT WILL BE FAVORED FOR HIGH WINDS IN THE
WIND PRONE AREAS AND PERHAPS SPREADING OVER PORTIONS OF THE
ADJACENT PLAINS IN SOUTHEAST WY. TEMPS WILL RISE AROUND 10 DEGREES
BUT STILL BE AVERAGE FOR EARLY JAN. WINDS WILL COME DOWN BY MON
NIGHT INTO TUES AS HIGHER PRESSURES MOVE INTO THE NORTHERN HIGH
PLAINS. TEMPS TRY TO MODERATE SOME BY TUES AND WED...MOST NOTABLY
OVER SOUTHEAST WY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 427 PM MST THU JAN 1 2015
CLOUDS ARE INCREASING ACROSS MOST OF THE SITES WITH VFR CIGS GENERALLY
5-10 THOUSAND FEET AGL. MVFR CIGS WILL BE POSSIBLE AT LAR THROUGH
THE EARLY NIGHT. A BAND OF LIGHT SNOW SHOWERS IS CURRENTLY MOVING
ACROSS NORTHERN COLORADO. A FEW FLURRIES COULD BE POSSIBLE THROUGH
06Z AT CYS AND SNY...ALTHOUGH VIS SHOULD NOT DROP SIGNIFICANTLY.
WINDS THROUGH THE PERIOD WILL BE LESS THAN 15 KTS.
&&
.FIRE WEATHER...
ISSUED AT 300 PM MST THU JAN 1 2015
SEE NO REAL CONCERNS INTO AT LEAST EARLY NEXT WEEK WITH COOL
TEMPERATURES AND SNOW COVER. WINDS LOOK TO BECOME GUSTY OVER THE
PLAINS SATURDAY THEN BECOME GUSTY SUNDAY INTO MONDAY AROUND THE SE
WYOMING MTNS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...JG
SHORT TERM...RE
LONG TERM...ZF
AVIATION...ZF
FIRE WEATHER...RE
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
456 AM EST SUN JAN 4 2015
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE WEST TONIGHT AND PUSH THROUGH
LATE SUNDAY FOLLOWED BY DRY HIGH PRESSURE. A STRONGER COLD FRONT
WILL DROP THROUGH WEDNESDAY EVENING...THEN COLD HIGH PRESSURE WILL
BUILD OVER THE REGION INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
PRE-DAWN...STRONG LOW LEVEL WARM AIR ADVECTION SCOURED OUT THE DENSE
FOG ACROSS COASTAL AREAS AND PARTS OF SE SOUTH CAROLINA JUST PRIOR
TO MIDNIGHT. TEMPS HAVE SOARED INTO THE LOWER 70S ALONG THE COAST
AND THIS SHATTERED THE SHALLOW INVERSION THAT ALLOWED SEA FOG AND
ADVECTION FOG TO FLOURISH. A SOLID BAND OF SHOWERS DEVELOPED EAST OF
I-95 OVERNIGHT AND THIS CONVECTION WAS ANCHORED ALONG A STRONG SPEED
AND MOISTURE CONVERGENCE ZONE IN THE BOUNDARY LAYER. RADAR RAINFALL
PRODUCTS ESTIMATED THAT SOME AREAS HAVE SAW 1-2 INCHES OF RAIN ACROSS
INLAND COLLETON/DORCHESTER/BERKELEY COUNTIES WHERE CELLS TRAINED ACROSS
THE SAME AREAS. OUR ENTIRE REGION NOW ENTRENCHED IN THE WARM SECTOR...
TEMPS IN THE MID TO UPPER 60S INLAND TO SOME LOWER 70S ALONG THE
SOUTH CAROLINA COAST. WINDS HAVE GUSTED OVER 35 MPH AT THE CHARLESTON
AIRPORT AHEAD OF THE BAND OF RAIN AND NOW LOW STRATUS WAS FILLING
BACK IN ACROSS SE GEORGIA WHERE SOME DRIER LOW LEVELS WERE PUNCHING
IN FROM THE SW. BOTH EVENTS INDICATIVE OF THE IMMENSE MESOSCALE
COMPLEXITIES WE HAVE SEEN EARLY THIS MORNING.
THE AXIS OF VORTICITY AND LOW-LEVEL CONVERGENCE COULD CONTINUE TO SUPPORT
AT LEAST SCATTERED SHOWERS ESPECIALLY OVER NORTHERN COASTAL COUNTIES
INTO THE MID/LATE MORNING. HOWEVER...THE MAIN PRECIPITATION EVENT WILL
ARRIVE THIS AFTERNOON AN INCREASINGLY ELONGATED/POSITIVELY TILTED
UPPER SHORTWAVE TROUGH EMBEDDED WITHIN A FAST WESTERLY FLOW WILL DRIVE
A SURFACE COLD FRONT INTO THE SOUTHEAST LATER THIS AFTERNOON AND EVENING.
AHEAD OF THE FRONT...STRONG LOW-LEVEL WINDS WILL MAINTAIN AN UNSEASONABLY
STRONG WARM SECTOR INTO THE REGION...MARKED BY TEMPERATURES IN THE UPPER
70S AND DEWPOINTS IN THE MID/UPPER 60S. SOME AREAS COULD REACH 80 DEGREES
THIS AFTERNOON IS WE SEE BREAKS FOR A WHILE. FORECAST THINKING FROM
LATEST MODEL ANALYSIS HAS NOT CHANGED MUCH IN TIMING THE ADVANCING
PRE-FRONTAL CONVECTIVE RAINS THIS AFTERNOON. STRONG TROPOSPHERIC WINDS
COULD SUPPORT QUASI- LINEAR CONVECTION INCLUDING BOWING SEGMENTS AND
STRONG/ISOLATED DAMAGING WIND GUSTS. HOWEVER...LIMITED LOW LEVEL
INSTABILITY AND POOR MID LEVEL LAPSE RATES WILL LIKELY PRECLUDE A
SIGNIFICANT SEVERE WEATHER EVENT. HOWEVER...ISOLATED SEVERE WEATHER
IS CERTAINLY POSSIBLE THIS AFTERNOON AND THE LOCATION THAT CAUGHT
OUR FORECAST INTEREST EARLY THIS MORNING WAS ACROSS PARTS OF SE
GEORGIA. THE LATEST OPERATIONAL RAP INDICATES POTENTIAL FOR MUCAPES
AND SBCAPES TO APPROACH 1000 J/KG TO THE SOUTH OF I-16 BY MID
AFTERNOON. THIS BUOYANCY WHILE LIMITED BY A POOR 500 MB-700 MB
LAYER DOES OFFER SOME DRY AIR ALOFT AND A POTENTIAL FOR SOME ENHANCED
CONVECTIVE WIND GUSTS. THE 00Z NSSL WRF MODEL PAINTS THE HIGHEST
FORECAST REFLECTIVITIES WITH BETTER LINEAR CONVECTIVE ORGANIZATION
DOWN IN THIS REGION AS WELL.
IF TEMPS WARM A LITTLE MORE THAN EXPECTED ALONG THE CHARLESTON COASTAL
CORRIDOR LATER THIS AFTERNOON...GUSTY WINDS OVER 35 MPH ARE POSSIBLE
ON AREA BRIDGES BUT THIS IS UNCERTAIN AT THIS POINT.
LAKE WINDS...WITHIN THE WARM SECTOR THE POTENTIAL FOR 25 KNOT
SOUTH/SOUTHWEST WIND GUSTS APPEARS SUFFICIENT TO JUSTIFY MAINTAINING
THE LAKE WIND ADVISORY ALONG LAKE SHORES FOR LAKE MOULTRIE VALID
10 AM UNTIL 5 PM TODAY.
THE COLD FRONT WILL SHIFT OFFSHORE BY MIDNIGHT TONIGHT...FOLLOWED
BY WEAK BUT DRY HIGH PRESSURE THROUGH TUESDAY. BY DAYBREAK MONDAY...
COLD ADVECTION WILL PUSH TEMPERATURES INTO THE 40S AT MOST LOCATIONS.
CLOUDS WILL BEGIN TO SCATTER OUT FROM THE WEST LATER TONIGHT.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
THE UPPER LEVEL PATTERN BECOMES ZONAL MONDAY THROUGH WEDNESDAY. DRY
HIGH PRESSURE WILL SPREAD INTO THE SOUTHEAST UNITED STATES ON MONDAY
THOUGH MODEST WNW FLOW AROUND 850 MB WILL SUPPORT DOWNSLOPE WARMING
AND HIGHS NEAR 60.
THE SURFACE HIGH WILL SHIFT OFF THE MID-ATLANTIC COAST MONDAY NIGHT
WITH A BRIEF RETURN FLOW AND INCREASING WSW LOW-LEVEL WINDS. WARM
AIR ADVECTION ON TUESDAY AND MOSTLY SUNNY SKIES WILL ALLOW TEMPS TO
REBOUND INTO THE MIDDLE 60S.
BOUNDARY LAYER FLOW VEERS AROUND TO THE NW LATE TUESDAY NIGHT INTO
WEDNESDAY...THOUGH 20-25 KT OF WNW 850 MB FLOW WILL MAINTAIN SOME
ADIABATIC WARMING. WEDNESDAY HIGH TEMPS WILL BE IN THE MID/UPPER 50S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
A DIGGING LONGWAVE TROUGH SHIFTS THROUGH THE AREA WEDNESDAY NIGHT
AND THURSDAY WITH A STRONG COLD FRONT DROPPING THROUGH THE AREA
WEDNESDAY EVENING. IMPRESSIVE COLD AIR ADVECTION WILL ENSUE AS A
VERY DRY HIGH PRESSURE AIRMASS DROPS SOUTHEAST. THE ECMWF HAS
GENERALLY BEEN THE COLDER OF THE MODELS WITH THIS SYSTEM...THOUGH IT
HAS MODERATED SOMEWHAT IN RECENT RUNS. NEVERTHELESS...A COLD 36 HRS
IS IN STORE. THURSDAY MORNING WILL LIKELY DROP INTO THE LOWER TO
MIDDLE 20S...COINCIDENT WITH 15-20 KT WINDS. OUR LATEST APPARENT
TEMPERATURE GRIDS SHOW THE POTENTIAL FOR WIND CHILL ADVISORY
CRITERIA FOR A FEW HOURS LATE WEDNESDAY NIGHT. IT IS WORTH NOTING
THAT OUR CRITERIA FOR ISSUING WIND CHILL ADVISORIES INCREASED ON
DECEMBER 1ST 2014. THE NEW CRITERIA IS 15 DEGREES IN COASTAL
LOCATIONS OR 10 DEGREES INLAND. WE WILL ADD MENTION TO THE HAZARDOUS
WEATHER OUTLOOK.
STRONG COLD ADVECTION CONTINUING ON THURSDAY WILL YIELD BLUSTERY
CONDITIONS. BASED ON THE LATEST THICKNESS PROGS WE LOWERED HIGHS TO
THE UPPER 30S NORTH TO LOWER 40S SOUTH. THURSDAY NIGHT WILL AGAIN BE
COLD AS HIGH PRESSURE REMAINS TO THE WEST. THERE WERE EARLIER
INDICATIONS THAT THE BOUNDARY LAYER COULD DECOUPLE AND ALLOW FOR LOW
TEMPS IN THE TEENS. MORE RECENT MODEL RUNS SHOW A WEAK SHORTWAVE
MOVING THROUGH OVERNIGHT WITH STRENGTHENING 850 MB WINDS PREVENTING
SURFACE WINDS FROM GOING CALM. WE MAINTAINED LOW TEMPS IN THE LOW TO
MID 20S.
THE UPPER LEVEL PATTERN TRANSITIONS TO A BROAD TROUGH ACROSS THE
CENTRAL UNITED STATES FRIDAY INTO THE WEEKEND WITH THE SURFACE HIGH
EVENTUALLY MOVING INTO THE NORTHEAST STATES. MOISTURE WILL BEGIN TO
INCREASE LATE IN THE WEEKEND WITH INCREASING CLOUDS AND POSSIBLE
RAIN SHOWERS SATURDAY NIGHT AND SUNDAY. TEMPS WILL REMAIN BELOW
NORMAL BUT HIGHS WILL GENERALLY BE IN THE 50S.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
CONDITIONS HAVE RAPIDLY IMPROVED AT THE TERMINALS OVERNIGHT AS STRATUS
WAS PUNCTUATED BY MUCH WARMER SURFACE TEMPS...STRONG LOW LEVEL
WINDS AND WEAKER INVERSIONS. THE NAM SHOWS SOME SLIGHTLY WEAKER
WINDS OFF THE DECK THROUGH DAYBREAK WITH A POCKET OF DRIER AIR AT
925 MB. THIS WILL SPELL A RETURN OF IFR OR LIFR CIGS BUT DENSE
FOG REMAINS UNLIKELY. WE HAVE TEMPO PERIODS FOR CONVECTIVE RAINS
THIS AFTERNOON AT BOTH AIRPORTS. IT WILL BE QUITE GUSTY TODAY IF
CLOUDS THIN AND THERE ARE SOME BREAKS LATE IN THE MORNING. MVFR
CIGS POSSIBLE THIS EVENING BUT OVERALL IMPROVING CONDITIONS
BECOMING LIKELY BY THE END OF THE 06Z TAF PERIOD.
EXTENDED AVIATION OUTLOOK...VFR.
&&
.MARINE...
DENSE SEA FOG DIFFICULT TO SCOUR OUT OVER THE COOLEST SHELF WATERS
AND MAY BE AROUND FOR MUCH OF THE MORNING AND PERHAPS INTO THE
AFTERNOON OR EARLY EVENING HOURS. WE HAVE MARINE FOG ADVISORIES
OVER NEAR SHORE WATERS AND PER RECENT CALL WITH CHARLESTON PILOT
OFFICE WE MAY NEED TO RE-ISSUE IN THE HARBOR THIS MORNING. VSBYS
NEAR ZERO AT TIMES.
THE COOL STABLE NEAR SHORE WATERS TYPIFIED BY THE 5-7 KT OF WIND
OVERNIGHT AT GRAYS REEF WHILE TEMPS REACHING THE MID 60S ALONG
THE GEORGIA COAST SUPPORTIVE OF 15 KT WINDS WITH THE STRONGEST FLOW
RELEGATED TO WARMER WATERS OFFSHORE. THE SMALL CRAFT ADVISORIES IN
OUR NEAR SHORE WATERS WILL BE MARGINAL TODAY ONCE YOU GET AWAY
FROM THE LAND/SEA INTERFACE BUT WE MAINTAINED 4-6 FT SEAS TO
KEEP PERSISTENCE. THE HIGHEST SEAS IN NEAR SHORE LEGS SHOULD OCCUR
ACROSS THE NORTHEAST PART OF AMZ350. THE CHARLESTON HARBOR WILL
BE GUSTY AT TIMES TODAY...ESPECIALLY THE UPPER REACHES WHERE THE
WARMER SURFACE TEMPS OCCUR. THE FRONT WILL MOVE OFFSHORE LATER
TONIGHT WITH SOME JETTING OF THE W AND NW FLOW OFF THE GEORGIA
COAST. WE BUMPED UP WINDS A BIT FROM GRAYS REEF SEAWARD TO TREND.
WINDS/SEAS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA MONDAY
THROUGH WEDNESDAY. CONDITIONS QUICKLY DETERIORATE WEDNESDAY EVENING
BEHIND A STRONG COLD FRONT. STRONG LOW-LEVEL WINDS AND COLD AIR
ADVECTION WILL YIELD WINDS TURNING AROUND TO THE NORTH AND
INCREASING TO 25-30 KT. FREQUENT 35 KT GUSTS ARE INCREASINGLY
LIKELY WEDNESDAY NIGHT INTO THURSDAY MORNING ACROSS THE WARMER
WATERS BEYOND ABOUT 15 NM FROM SHORE. A PERIOD OF GALE
WATCHES/WARNINGS IS LIKELY FOR PORTIONS OF THE WATERS DURING THIS
TIME.
CONDITIONS QUICKLY IMPROVE LATER THURSDAY INTO THE WEEKEND AS THE
HIGH PRESSURE SYSTEM WEAKENS AND EVENTUALLY SHIFTS NORTHEAST.
&&
.CLIMATE...
RECORD HIGH TEMPERATURES JAN 4...
CHS 77/2005 AND PREVIOUS...
CXM 75/1955...
SAV 80/2004...
RECORD HIGH MINIMUM TEMPERATURES JAN 4...
CHS 58/1950 AND PREVIOUS...
CXM 61/2007...
SAV 60/2004 AND PREVIOUS...
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...LAKE WIND ADVISORY FROM 10 AM THIS MORNING TO 5 PM EST THIS
AFTERNOON FOR SCZ045.
MARINE...DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR AMZ350-352-
354.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR AMZ352.
SMALL CRAFT ADVISORY UNTIL 5 AM EST MONDAY FOR AMZ350.
SMALL CRAFT ADVISORY UNTIL 11 AM EST MONDAY FOR AMZ374.
SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 5 PM EST THIS
AFTERNOON FOR AMZ330.
&&
$$
NEAR TERM...
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...JRL
CLIMATE...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
438 AM EST SUN JAN 4 2015
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE WEST TONIGHT AND PUSH THROUGH
LATE SUNDAY FOLLOWED BY DRY HIGH PRESSURE. A STRONGER COLD FRONT
WILL DROP THROUGH WEDNESDAY EVENING...THEN COLD HIGH PRESSURE WILL
BUILD OVER THE REGION INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
PRE-DAWN...STRONG LOW LEVEL WARM AIR ADVECTION SCOURED OUT THE DENSE
FOG ACROSS COASTAL AREAS AND PARTS OF SE SOUTH CAROLINA JUST PRIOR
TO MIDNIGHT. TEMPS HAVE SOARED INTO THE LOWER 70S ALONG THE COAST
AND THIS SHATTERED THE SHALLOW INVERSION THAT ALLOWED SEA FOG AND
ADVECTION FOG TO FLOURISH. A SOLID BAND OF SHOWERS DEVELOPED EAST OF
I-95 OVERNIGHT AND THIS CONVECTION WAS ANCHORED ALONG A STRONG SPEED
AND MOISTURE CONVERGENCE ZONE IN THE BOUNDARY LAYER. RADAR RAINFALL
PRODUCTS ESTIMATED THAT SOME AREAS HAVE SAW 1-2 INCHES OF RAIN ACROSS
INLAND COLLETON/DORCHESTER/BERKELEY COUNTIES WHERE CELLS TRAINED ACROSS
THE SAME AREAS. OUR ENTIRE REGION NOW ENTRENCHED IN THE WARM SECTOR...
TEMPS IN THE MID TO UPPER 60S INLAND TO SOME LOWER 70S ALONG THE
SOUTH CAROLINA COAST. WINDS HAVE GUSTED OVER 35 MPH AT THE CHARLESTON
AIRPORT AHEAD OF THE BAND OF RAIN AND NOW LOW STRATUS WAS FILLING
BACK IN ACROSS SE GEORGIA WHERE SOME DRIER LOW LEVELS WERE PUNCHING
IN FROM THE SW. BOTH EVENTS INDICATIVE OF THE IMMENSE MESOSCALE
COMPLEXITIES WE HAVE SEEN EARLY THIS MORNING.
THE AXIS OF VORTICITY AND LOW-LEVEL CONVERGENCE COULD CONTINUE TO SUPPORT
AT LEAST SCATTERED SHOWERS ESPECIALLY OVER NORTHERN COASTAL COUNTIES
INTO THE MID/LATE MORNING. HOWEVER...THE MAIN PRECIPITATION EVENT WILL
ARRIVE THIS AFTERNOON AN INCREASINGLY ELONGATED/POSITIVELY TILTED
UPPER SHORTWAVE TROUGH EMBEDDED WITHIN A FAST WESTERLY FLOW WILL DRIVE
A SURFACE COLD FRONT INTO THE SOUTHEAST LATER THIS AFTERNOON AND EVENING.
AHEAD OF THE FRONT...STRONG LOW-LEVEL WINDS WILL MAINTAIN AN UNSEASONABLY
STRONG WARM SECTOR INTO THE REGION...MARKED BY TEMPERATURES IN THE UPPER
70S AND DEWPOINTS IN THE MID/UPPER 60S. SOME AREAS COULD REACH 80 DEGREES
THIS AFTERNOON IS WE SEE BREAKS FOR A WHILE. FORECAST THINKING FROM
LATEST MODEL ANALYSIS HAS NOT CHANGED MUCH IN TIMING THE ADVANCING
PRE-FRONTAL CONVECTIVE RAINS THIS AFTERNOON. STRONG TROPOSPHERIC WINDS
COULD SUPPORT QUASI- LINEAR CONVECTION INCLUDING BOWING SEGMENTS AND
STRONG/ISOLATED DAMAGING WIND GUSTS. HOWEVER...LIMITED LOW LEVEL
INSTABILITY AND POOR MID LEVEL LAPSE RATES WILL LIKELY PRECLUDE A
SIGNIFICANT SEVERE WEATHER EVENT. HOWEVER...ISOLATED SEVERE WEATHER
IS CERTAINLY POSSIBLE THIS AFTERNOON AND THE LOCATION THAT CAUGHT
OUR FORECAST INTEREST EARLY THIS MORNING WAS ACROSS PARTS OF SE
GEORGIA. THE LATEST OPERATIONAL RAP INDICATES POTENTIAL FOR MUCAPES
AND SBCAPES TO APPROACH 1000 J/KG TO THE SOUTH OF I-16 BY MID
AFTERNOON. THIS BUOYANCY WHILE LIMITED BY A POOR 500 MB-700 MB
LAYER DOES OFFER SOME DRY AIR ALOFT AND A POTENTIAL FOR SOME ENHANCED
CONVECTIVE WIND GUSTS. THE 00Z NSSL WRF MODEL PAINTS THE HIGHEST
FORECAST REFLECTIVITIES WITH BETTER LINEAR CONVECTIVE ORGANIZATION
DOWN IN THIS REGION AS WELL.
IF TEMPS WARM A LITTLE MORE THAN EXPECTED ALONG THE CHARLESTON COASTAL
CORRIDOR LATER THIS AFTERNOON...GUSTY WINDS OVER 35 MPH ARE POSSIBLE
ON AREA BRIDGES BUT THIS IS UNCERTAIN AT THIS POINT.
LAKE WINDS...WITHIN THE WARM SECTOR THE POTENTIAL FOR 25 KNOT
SOUTH/SOUTHWEST WIND GUSTS APPEARS SUFFICIENT TO JUSTIFY MAINTAINING
THE LAKE WIND ADVISORY ALONG LAKE SHORES FOR LAKE MOULTRIE VALID
10 AM UNTIL 5 PM TODAY.
THE COLD FRONT WILL SHIFT OFFSHORE BY MIDNIGHT TONIGHT...FOLLOWED
BY WEAK BUT DRY HIGH PRESSURE THROUGH TUESDAY. BY DAYBREAK MONDAY...
COLD ADVECTION WILL PUSH TEMPERATURES INTO THE 40S AT MOST LOCATIONS.
CLOUDS WILL BEGIN TO SCATTER OUT FROM THE WEST LATER TONIGHT.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
THE UPPER LEVEL PATTERN BECOMES ZONAL MONDAY THROUGH WEDNESDAY. DRY
HIGH PRESSURE WILL SPREAD INTO THE SOUTHEAST UNITED STATES ON MONDAY
THOUGH MODEST WNW FLOW AROUND 850 MB WILL SUPPORT DOWNSLOPE WARMING
AND HIGHS NEAR 60.
THE SURFACE HIGH WILL SHIFT OFF THE MID-ATLANTIC COAST MONDAY NIGHT
WITH A BRIEF RETURN FLOW AND INCREASING WSW LOW-LEVEL WINDS. WARM
AIR ADVECTION ON TUESDAY AND MOSTLY SUNNY SKIES WILL ALLOW TEMPS TO
REBOUND INTO THE MIDDLE 60S.
BOUNDARY LAYER FLOW VEERS AROUND TO THE NW LATE TUESDAY NIGHT INTO
WEDNESDAY...THOUGH 20-25 KT OF WNW 850 MB FLOW WILL MAINTAIN SOME
ADIABATIC WARMING. WEDNESDAY HIGH TEMPS WILL BE IN THE MID/UPPER 50S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
A DIGGING LONGWAVE TROUGH SHIFTS THROUGH THE AREA WEDNESDAY NIGHT
AND THURSDAY WITH A STRONG COLD FRONT DROPPING THROUGH THE AREA
WEDNESDAY EVENING. IMPRESSIVE COLD AIR ADVECTION WILL ENSUE AS A
VERY DRY HIGH PRESSURE AIRMASS DROPS SOUTHEAST. THE ECMWF HAS
GENERALLY BEEN THE COLDER OF THE MODELS WITH THIS SYSTEM...THOUGH IT
HAS MODERATED SOMEWHAT IN RECENT RUNS. NEVERTHELESS...A COLD 36 HRS
IS IN STORE. THURSDAY MORNING WILL LIKELY DROP INTO THE LOWER TO
MIDDLE 20S...COINCIDENT WITH 15-20 KT WINDS. OUR LATEST APPARENT
TEMPERATURE GRIDS SHOW THE POTENTIAL FOR WIND CHILL ADVISORY
CRITERIA FOR A FEW HOURS LATE WEDNESDAY NIGHT. IT IS WORTH NOTING
THAT OUR CRITERIA FOR ISSUING WIND CHILL ADVISORIES INCREASED ON
DECEMBER 1ST 2014. THE NEW CRITERIA IS 15 DEGREES IN COASTAL
LOCATIONS OR 10 DEGREES INLAND. WE WILL ADD MENTION TO THE HAZARDOUS
WEATHER OUTLOOK.
STRONG COLD ADVECTION CONTINUING ON THURSDAY WILL YIELD BLUSTERY
CONDITIONS. BASED ON THE LATEST THICKNESS PROGS WE LOWERED HIGHS TO
THE UPPER 30S NORTH TO LOWER 40S SOUTH. THURSDAY NIGHT WILL AGAIN BE
COLD AS HIGH PRESSURE REMAINS TO THE WEST. THERE WERE EARLIER
INDICATIONS THAT THE BOUNDARY LAYER COULD DECOUPLE AND ALLOW FOR LOW
TEMPS IN THE TEENS. MORE RECENT MODEL RUNS SHOW A WEAK SHORTWAVE
MOVING THROUGH OVERNIGHT WITH STRENGTHENING 850 MB WINDS PREVENTING
SURFACE WINDS FROM GOING CALM. WE MAINTAINED LOW TEMPS IN THE LOW TO
MID 20S.
THE UPPER LEVEL PATTERN TRANSITIONS TO A BROAD TROUGH ACROSS THE
CENTRAL UNITED STATES FRIDAY INTO THE WEEKEND WITH THE SURFACE HIGH
EVENTUALLY MOVING INTO THE NORTHEAST STATES. MOISTURE WILL BEGIN TO
INCREASE LATE IN THE WEEKEND WITH INCREASING CLOUDS AND POSSIBLE
RAIN SHOWERS SATURDAY NIGHT AND SUNDAY. TEMPS WILL REMAIN BELOW
NORMAL BUT HIGHS WILL GENERALLY BE IN THE 50S.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
CONDITIONS HAVE RAPIDLY IMPROVED AT THE TERMINALS OVERNIGHT AS STRATUS
WAS PUNCTUATED BY MUCH WARMER SURFACE TEMPS...STRONG LOW LEVEL
WINDS AND WEAKER INVERSIONS. THE NAM SHOWS SOME SLIGHTLY WEAKER
WINDS OFF THE DECK THROUGH DAYBREAK WITH A POCKET OF DRIER AIR AT
925 MB. THIS WILL SPELL A RETURN OF IFR OR LIFR CIGS BUT DENSE
FOG REMAINS UNLIKELY. WE HAVE TEMPO PERIODS FOR CONVECTIVE RAINS
THIS AFTERNOON AT BOTH AIRPORTS. IT WILL BE QUITE GUSTY TODAY IF
CLOUDS THIN AND THERE ARE SOME BREAKS LATE IN THE MORNING. MVFR
CIGS POSSIBLE THIS EVENING BUT OVERALL IMPROVING CONDITIONS
BECOMING LIKELY BY THE END OF THE 06Z TAF PERIOD.
EXTENDED AVIATION OUTLOOK...VFR.
&&
.MARINE...
AT 3 AM...THE CHARLESTON PILOT BOAT REPORTED DECENT VSBYS OUT AT
BUOY CHARLIE BUT DID ENCOUNTER PATCHY FOG BANKS NEAR SHORE. WE
HAVE LITTLE DATA THIS MORNING BUT ARE JUST FINDING OUT THE FOG IS
NOW MORE EXTENSIVE AT 430 AM. ADVISORIES MAY BE REQUIRED ONCE AGAIN.
THE COOL STABLE NEAR SHORE WATERS TYPIFIED BY THE 5-7 KT OF WIND
OVERNIGHT AT GRAYS REEF WHILE TEMPS REACHING THE MID 60S ALONG
THE GEORGIA COAST SUPPORTIVE OF 15 KT WINDS WITH THE STRONGEST FLOW
RELEGATED TO WARMER WATERS OFFSHORE. THE SMALL CRAFT ADVISORIES IN
OUR NEAR SHORE WATERS WILL BE MARGINAL TODAY ONCE YOU GET AWAY
FROM THE LAND/SEA INTERFACE BUT WE MAINTAINED 4-6 FT SEAS TO
KEEP PERSISTENCE. THE HIGHEST SEAS IN NEAR SHORE LEGS SHOULD OCCUR
ACROSS THE NORTHEAST PART OF AMZ350. THE CHARLESTON HARBOR WILL
BE GUSTY AT TIMES TODAY...ESPECIALLY THE UPPER REACHES WHERE THE
WARMER SURFACE TEMPS OCCUR. THE FRONT WILL MOVE OFFSHORE LATER
TONIGHT WITH SOME JETTING OF THE W AND NW FLOW OFF THE GEORGIA
COAST. WE BUMPED UP WINDS A BIT FROM GRAYS REEF SEAWARD TO TREND.
WINDS/SEAS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA MONDAY
THROUGH WEDNESDAY. CONDITIONS QUICKLY DETERIORATE WEDNESDAY EVENING
BEHIND A STRONG COLD FRONT. STRONG LOW-LEVEL WINDS AND COLD AIR
ADVECTION WILL YIELD WINDS TURNING AROUND TO THE NORTH AND
INCREASING TO 25-30 KT. FREQUENT 35 KT GUSTS ARE INCREASINGLY
LIKELY WEDNESDAY NIGHT INTO THURSDAY MORNING ACROSS THE WARMER
WATERS BEYOND ABOUT 15 NM FROM SHORE. A PERIOD OF GALE
WATCHES/WARNINGS IS LIKELY FOR PORTIONS OF THE WATERS DURING THIS
TIME.
CONDITIONS QUICKLY IMPROVE LATER THURSDAY INTO THE WEEKEND AS THE
HIGH PRESSURE SYSTEM WEAKENS AND EVENTUALLY SHIFTS NORTHEAST.
&&
.CLIMATE...
RECORD HIGH TEMPERATURES JAN 4...
CHS 77/2005 AND PREVIOUS...
CXM 75/1955...
SAV 80/2004...
RECORD HIGH MINIMUM TEMPERATURES JAN 4...
CHS 58/1950 AND PREVIOUS...
CXM 61/2007...
SAV 60/2004 AND PREVIOUS...
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...LAKE WIND ADVISORY FROM 10 AM THIS MORNING TO 5 PM EST THIS
AFTERNOON FOR SCZ045.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 5 PM EST THIS
AFTERNOON FOR AMZ330.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR AMZ352.
SMALL CRAFT ADVISORY UNTIL 5 AM EST MONDAY FOR AMZ350.
SMALL CRAFT ADVISORY UNTIL 11 AM EST MONDAY FOR AMZ374.
&&
$$
NEAR TERM...
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...JRL
CLIMATE...
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1248 AM EST SUN JAN 4 2015
.PREV DISCUSSION... /ISSUED 638 PM EST SAT JAN 3 2015/
PREV DISCUSSION... /ISSUED 308 PM EST SAT JAN 3 2015/
.SEVERE STORMS POSSIBLE NW GEORGIA AFTER MIDNIGHT...
.HEAVY RAIN LIKELY MUCH OF NORTH GEORGIA TONIGHT AND SUNDAY
MORNING...
SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
ONLY MINOR REFINEMENTS MADE TO GRIDS SINCE LAST DISCUSSION /SEE
BELOW/ BASED ON OBSERVED TRENDS AND LATEST HRRR GUIDANCE. APPEARS
LINE OF CONVECTION STILL ON TARGET TO MOVE INTO NW GEORGIA AFTER
06Z THEN PUSH INTO ATL METRO AROUND 11-12Z WHILE ON A WEAKENING
TREND. WIDESPREAD DRIZZLE AND FOG WITH SCT -SHRA TO CONTINUE
UNTIL THEN.
PRECIP SHOULD END QUICKLY BEHIND MAIN PRE-FRONTAL SQUALL LINE.
HAVE MANUALLY DRAWN POPS AS LACK OF GOOD HOURLY MODEL GUIDANCE
EXISTS TODAY. COULD SEE VERY ISOLD CONVECTION BEHIND THIS LINE SUN
AFTERNOON BUT SUBJECTIVE EXPERIENCE IN THIS PATTERN IS COVERAGE
AND INTENSITY WILL BE MUCH LESS THAN INDICATED BY MODEL GUIDANCE.
WINDS SHOULD BE STRONG BUT REMAIN BELOW ADVISORY CRITERIA SUN AND
SUN EVENING.
SNELSON
LONG TERM /MONDAY THROUGH SATURDAY/...
VERY FEW CHANGES NEEDED FOR THE LONG TERM PORTION OF THE FORECAST.
HIGH PRESSURE WILL MOVE OFFSHORE THE MID ATLANTIC COAST ON MONDAY IN
ADVANCE OF A COLD FRONT ON TUESDAY. TUESDAYS FRONT IS EXPECTED TO BE
DRY.
A STRONG AREA OF HIGH PRESSURE WILL BUILD BEHIND THE FRONT WEDNESDAY
INTO THURSDAY...BRINGING A MUCH COLDER AND DRIER AIRMASS TO THE
SOUTHEAST STATES. THERE WERE SOME EARLIER DIFFERENCES BETWEEN THE
LONGER TERM MODELS WITH FORECAST MINS AND MAX TEMPS WEDNESDAY INTO
THURSDAY...THE GFS HAS TRENDED A LITTLE COLDER AND CLOSER TO THE
ECMWF VALUES.
IN ADDITION TO THE COLDER TEMPERATURES...BREEZY OR EVEN WINDY
CONDITIONS ARE EXPECTED WEDNESDAY INTO EARLY THURSDAY. VALUES COULD
APPROACH WIND ADVISORY CRITERIA...AND BRING LOW WIND CHILLS.
TEMPERATURES ARE EXPECTED TO MODERATE FAIRLY QUICKLY FRIDAY INTO
THE WEEKEND.
NLISTEMAA
HYDROLOGY...
STILL ON TRACK TO SEE 1 TO 2 INCHES WITH AMOUNTS OVER 1.5 INCHES
CONFINED TO NE GA. BASED ON THIS EXPECTATION AND FFG HAVE DECIDED
NOT TO ISSUE ANY KIND OF FLOOD WATCH. WILL CONTINUE TO MONITOR
THIS EVENING.
SNELSON
PREV DISCUSSION... /ISSUED 149 PM EST SAT JAN 3 2015/
UPDATE... NEAR TERM FCST APPEARS ON TRACK. MAIN CONCERN IS
POTENTIAL FOR SVR STORMS AND HVY RAIN. 12Z SYNOPTIC MODELS AND
HIRES GUIDANCE INDICATING LINE OF CONVECTION SHOULD MOVE INTO NW
CORNER AROUND OR AFTER 06Z. NAM AND GFS 0-1KM BULK SHEAR
/35-45KTS/ AND MLCAPE /100-250 J/KG/ FAVORABLE FOR QLCS STORMS
WITH ISOLD WIND DMG AND EVEN BRIEF TORNADO POSSIBLE IN THE NW
1/3RD OF GA BETWEEN 06Z AND 12Z...MAINLY NORTH OF I-85.
LATEST QPF GUIDANCE INDICATING 1 TO 2 INCHES THRU 00Z MON WITH
ONLY NE GA AREA EXPECTING AMOUNTS OF 1.5 INCHES. 3HR FFG IS QUITE
LOW /2-2.5 INCHES/ IN NORTH GA DUE TO ANTECEDENT RAINFALL THE LAST
36 HRS. WILL BE COLLABORATING AND LOOKING AT A LITTLE MORE DATA
BEFORE DECIDING BUT FOR NOW HOLDING OFF ON WATCH.
SNELSON
&&
.AVIATION...
06Z UPDATE...
CHALLENGING FORECAST IS ONGOING TONIGHT AS WARM FRONT ERODES WEDGEQUICKLY
FROM SW TO NE AND CONVERTS LIFR CONDITIONS TO IFR AND EVENTUALLY
MVFR. SUCH IS THE CASE RIGHT NOW OVER ATL AS OVC002 HAS
TRANSITIONED TO OVC008 AND NOT OUT OF THE QUESTION TO SEE SOME
MVFR BEFORE MAIN RAIN SHIELD MOVES BACK IN. TIMING OF +SHRA STILL
LOOKS GOOD FOR AROUND 14Z WITH ISOLD TSRA AS WELL. WILL MONITOR
TRENDS FOR POSSIBLE INCLUSION OF TS INTO THE TAF SET.
OTHERWISE...EXPECT MVFR TO DEVELOP IN POST FRONT ENVIRONMENT AND
BE SLOW TO CLEAR OUT. WINDS WILL BE GUSTY DURING THE DAY AS WELL
WITH VALUES CLOSE TO 25 KTS LIKELY.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON TS POTENTIAL.
HIGH ON REMAINING ELEMENTS.
DEESE
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 65 35 54 32 / 100 10 0 0
ATLANTA 62 34 50 31 / 100 10 0 0
BLAIRSVILLE 58 29 46 26 / 100 10 5 0
CARTERSVILLE 61 31 46 28 / 100 10 0 0
COLUMBUS 67 36 53 33 / 100 10 0 0
GAINESVILLE 61 33 50 31 / 100 10 0 0
MACON 69 37 55 33 / 100 10 5 0
ROME 60 30 45 26 / 100 10 5 0
PEACHTREE CITY 63 34 51 28 / 100 10 0 0
VIDALIA 75 42 58 39 / 80 70 5 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...DEESE
LONG TERM....TDP
AVIATION...DEESE
AREA FORECAST DISCUSSION
NWS JACKSON KY
342 AM EST SUN JAN 4 2015
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 320 AM EST SUN JAN 4 2015
07Z SFC ANALYSIS SHOWS A DEEPENING AREA OF LOW PRESSURE MOVING INTO
THE OHIO VALLEY. THIS LOW IS DRAGGING A COLD FRONT THROUGH KENTUCKY
TRAILING A BAND OF STEADY LIGHT TO MODERATE RAIN SHOWERS PASSING
THROUGH EASTERN KENTUCKY. THE HEAVIER SHOWERS HAVE SETTLED DOWN AND
MOVED OFF TO THE EAST WHILE MORE SCATTERED SHOWERS ARE FOUND OVER
CENTRAL KENTUCKY ALONG AND JUST AHEAD OF THE COLD FRONT. EAST
KENTUCKY IS ENJOYING A VERY MILD EARLY JANUARY NIGHT AHEAD OF THE
COLD FRONT WITH TEMPERATURES IN THE MID AND UPPER 50S WHILE DEWPOINTS
ARE NOT MUCH LOWER. WINDS HAVE BEEN RATHER LIGHT FROM THE SOUTH
THROUGH THE AREA DESPITE THE TIGHTENING PRESSURE GRADIENT AND WINDS
ROARING JUST OFF THE SFC...AS SEEN IN THE JKL VWP.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM AS WE
ENTER A PERIOD OF SHARP WX TRANSITION. A FAIRLY DEEP FULL LATITUDE
TROUGH WILL SWEEP INTO THE OHIO VALLEY TODAY WITH ITS CORE BATCH OF
ENERGY PASSING THROUGH EAST KENTUCKY BY 00Z. VERY FAST FLOW THROUGH
THE BASE OF THE LARGE...BUT NOT SETTLING TOO FAR SOUTH...TROUGH THEN
WILL KEEP MINOR WAVES MOVING PAST ALOFT TONIGHT AND THROUGH THE DAY
MONDAY. GIVEN THE CLOSE MODEL AGREEMENT HERE WILL CONTINUE TO FAVOR A
BLEND OF THE HRRR AND NAM12 TODAY FOLLOWED BY THE ECMWF AND NAM12 FOR
TONIGHT AND MONDAY.
SENSIBLE WEATHER WILL FEATURE THE WARMEST TEMPERATURES OF THE
FORECAST EARLY THIS MORNING AHEAD OF THE COLD FRONT. THIS BOUNDARY
WILL GO THROUGH BY MID MORNING...THOUGH...AND START US ON OUR DESCENT
TO SINGLE DIGIT TEMPS THAT WILL BE IN HERE BY THURSDAY MORNING. THE
RAIN ASSOCIATED WITH THE COLD FRONT THIS MORNING WILL COME TO AN END
WITH ITS PASSAGE...THOUGH THAT SHORTWAVE CROSSING OVERHEAD THIS
AFTERNOON AND A COMBINATION OF WRAP AROUND AND UPSLOPE FLOW WILL
LIKELY LEAD TO A REDEVELOPMENT OF LIGHT PCPN MOVING IN FROM THE
NORTHWEST BY LATE AFTERNOON. AS TEMPERATURES COOL INTO THE EVENING
EXPECT THE LINGERING LIGHT SHOWERS TO TRANSITION TO SNOW SHOWERS FOR
A BRIEF TIME. THESE WILL BE A BIT MORE ROBUST IN THE HIGHER TERRAIN
NEAR THE VIRGINIA BORDER POTENTIALLY RESULTING IN A DUSTING OF
ACCUMULATION BY EARLY MONDAY MORNING. DRIER AIR AND ARRIVING HIGH
PRESSURE WILL PUT AN END TO ANY LEFTOVER FLURRIES MONDAY MORNING...
THOUGH TEMPERATURES WILL STRUGGLE TO CLIMB OUT OF THE 20S.
ONCE AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPS...TD...
AND WINDS UP TO 21Z TODAY AND THEN THE SUPERBLEND THROUGH 00Z
TUESDAY. DID MAKE SOME SLIGHT ADJUSTMENTS TO POINT TEMPERATURE DATA
FOR MAXES AND MINS THROUGH THE PERIOD. AS FOR POPS...ENDED UP SIMILAR
TO A BLEND OF THE GUIDANCE TODAY BUT WENT ABOVE ALL OF IT FOR THE
LIGHT RAIN AND SNOW CHANCES LATER THIS EVENING AND THE FIRST PART OF
TONIGHT...MONDAY WAS KEPT DRY IN LINE WITH ALL THE MOS.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 342 AM EST SUN JAN 4 2015
THE EXTENDED PORTION OF THE FORECAST WILL BEGIN ON MONDAY NIGHT WITH
A PROGRESSIVE UPPER LEVEL PATTERN THAT KEEPS A BROAD TROUGH OVER THE
NORTHEASTERN CONUS THROUGH MUCH OF THE EXTENDED. THROUGH
SATURDAY...A SERIES OF SHORTWAVES DIVE SOUTHEAST INTO THE OH VALLEY
REGION. THE FIRST WAVE MOVES THROUGH ON TUESDAY AND THOUGH MOISTURE
STARVED AND MOST OF THE LIFT AND MOISTURE BEING NORTH...WILL KEEP
SOME FLURRIES AND SNOW SHOWERS JUST SKIRTING THE NORTHERN PORTION OF
THE CWA. MODEL SOUNDINGS KEEP THE LOWER LEVELS QUITE DRY SO COULD
ALSO GO COMPLETELY DRY OVER THE AREA WITH THIS FEATURE. THE FIRST
SHOT OF COLDER AIR FILTERS IN BEHIND THIS FRONT FOR WEDNESDAY. THEN
ANOTHER SHORTWAVE MOVES THROUGH LATER IN THE DAY ON WEDNESDAY BUT
THE FRONT BEING DRY WITH THIS ONE WITH JUST CLOUD COVER EXPECTED.
THE COLD AIR BEHIND THIS FEATURE WILL BRING SOME FRIGID AIR INTO
EASTERN KENTUCKY. DOMINANT SURFACE HIGH PRESSURE WILL RESIDE FROM
THE UPPER PLAINS AND MOVES SOUTHEAST INTO THE MS VALLEY AND TN
VALLEY...KEEPING EASTERN KENTUCKY DRY THROUGH MUCH OF THE EXTENDED.
THE COLD AIR AND WIND EXPECTED FOR THURSDAY WILL PRODUCE SOME WIND
CHILLS INTO THE NEGATIVE TEENS. BECAUSE OF THIS...WILL MENTION THIS
IN THE HWO AS WELL AS ISSUE AN SPS FOR THIS. MODELS DIVERGE
SIGNIFICANTLY AT THE END OF THE EXTENDED AS THE GFS KEEPS THE AREA
DRY BUT THE EURO HAS THE THE UPPER TROUGH LIFTING NORTH ALLOWING A
NEW FEATURE TO DEVELOP AND MOVE NORTHEAST OUT OF THE GULF OF
MEXICO. DID GET SOME POPS FROM THE ALL MODEL BLEND SO WENT WITH
SLIGHTLY LOWER POPS KEEP SLIGHT CHANCE OVER THE AREA. THIS IS DUE
TO COLLABORATION WITH NEIGHBORING OFFICES AS WELL AS THE TRENDS OF
THE EURO. THE AIR MASS IN PLACE DURING THAT TIME IS ALSO QUITE DRY TO
OVERCOME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1255 AM EST SUN JAN 4 2015
THE COLD FRONT WILL START TO PUSH EAST ACROSS THE AREA AT A QUICKER
PACE SOON AS THE LOW PRESSURE CENTER NORTH OF KENTUCKY FURTHER
DEEPENS. THE LOCALLY HEAVY RAIN IS NOW CONFINED TO THE EASTERN
PORTION OF THE AREA AND IS SHIFTING EAST...AS WELL. THE LINGERING
RAIN OVER THE AREA WILL REDUCE VISIBILITIES AT TIMES PARTICULARLY
WHEN SOME PATCHY FOG MOVES OVER THE TAF SITES. WITH THE HEAVIER RAINS
NOW SHIFTING EAST OF THE TAF SITES...CIGS WILL MAINLY BE IN THE LOW
AND MID REACHES OF THE VFR CATEGORY. THE STEADY RAIN WILL END BEFORE
DAYBREAK AT MOST SPOTS...BUT ANOTHER DISTURBANCE COULD BRING A FEW
RAIN SHOWERS BY THE MIDDLE OF THE AFTERNOON AND INTO THE EVENING
HOURS. THIS WILL SEND LOWER CIGS BACK INTO THE AREA...AS WELL. WITH
900MB WINDS AROUND 50 KNOTS...LLWS WILL REMAIN A CONCERN INTO SUNDAY
MORNING. AS THE FRONT EXITS SUNDAY...WINDY CONDITIONS WILL LIKELY
DEVELOP BY LATE MORNING FROM THE WEST TO NORTHWEST...CONTINUING
THROUGH THE AFTERNOON HOURS AS WINDS GUST UP TO 25 KNOTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
320 AM EST SUN JAN 4 2015
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 320 AM EST SUN JAN 4 2015
07Z SFC ANALYSIS SHOWS A DEEPENING AREA OF LOW PRESSURE MOVING INTO
THE OHIO VALLEY. THIS LOW IS DRAGGING A COLD FRONT THROUGH KENTUCKY
TRAILING A BAND OF STEADY LIGHT TO MODERATE RAIN SHOWERS PASSING
THROUGH EASTERN KENTUCKY. THE HEAVIER SHOWERS HAVE SETTLED DOWN AND
MOVED OFF TO THE EAST WHILE MORE SCATTERED SHOWERS ARE FOUND OVER
CENTRAL KENTUCKY ALONG AND JUST AHEAD OF THE COLD FRONT. EAST
KENTUCKY IS ENJOYING A VERY MILD EARLY JANUARY NIGHT AHEAD OF THE
COLD FRONT WITH TEMPERATURES IN THE MID AND UPPER 50S WHILE DEWPOINTS
ARE NOT MUCH LOWER. WINDS HAVE BEEN RATHER LIGHT FROM THE SOUTH
THROUGH THE AREA DESPITE THE TIGHTENING PRESSURE GRADIENT AND WINDS
ROARING JUST OFF THE SFC...AS SEEN IN THE JKL VWP.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM AS WE
ENTER A PERIOD OF SHARP WX TRANSITION. A FAIRLY DEEP FULL LATITUDE
TROUGH WILL SWEEP INTO THE OHIO VALLEY TODAY WITH ITS CORE BATCH OF
ENERGY PASSING THROUGH EAST KENTUCKY BY 00Z. VERY FAST FLOW THROUGH
THE BASE OF THE LARGE...BUT NOT SETTLING TOO FAR SOUTH...TROUGH THEN
WILL KEEP MINOR WAVES MOVING PAST ALOFT TONIGHT AND THROUGH THE DAY
MONDAY. GIVEN THE CLOSE MODEL AGREEMENT HERE WILL CONTINUE TO FAVOR A
BLEND OF THE HRRR AND NAM12 TODAY FOLLOWED BY THE ECMWF AND NAM12 FOR
TONIGHT AND MONDAY.
SENSIBLE WEATHER WILL FEATURE THE WARMEST TEMPERATURES OF THE
FORECAST EARLY THIS MORNING AHEAD OF THE COLD FRONT. THIS BOUNDARY
WILL GO THROUGH BY MID MORNING...THOUGH...AND START US ON OUR DESCENT
TO SINGLE DIGIT TEMPS THAT WILL BE IN HERE BY THURSDAY MORNING. THE
RAIN ASSOCIATED WITH THE COLD FRONT THIS MORNING WILL COME TO AN END
WITH ITS PASSAGE...THOUGH THAT SHORTWAVE CROSSING OVERHEAD THIS
AFTERNOON AND A COMBINATION OF WRAP AROUND AND UPSLOPE FLOW WILL
LIKELY LEAD TO A REDEVELOPMENT OF LIGHT PCPN MOVING IN FROM THE
NORTHWEST BY LATE AFTERNOON. AS TEMPERATURES COOL INTO THE EVENING
EXPECT THE LINGERING LIGHT SHOWERS TO TRANSITION TO SNOW SHOWERS FOR
A BRIEF TIME. THESE WILL BE A BIT MORE ROBUST IN THE HIGHER TERRAIN
NEAR THE VIRGINIA BORDER POTENTIALLY RESULTING IN A DUSTING OF
ACCUMULATION BY EARLY MONDAY MORNING. DRIER AIR AND ARRIVING HIGH
PRESSURE WILL PUT AN END TO ANY LEFTOVER FLURRIES MONDAY MORNING...
THOUGH TEMPERATURES WILL STRUGGLE TO CLIMB OUT OF THE 20S.
ONCE AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPS...TD...
AND WINDS UP TO 21Z TODAY AND THEN THE SUPERBLEND THROUGH 00Z
TUESDAY. DID MAKE SOME SLIGHT ADJUSTMENTS TO POINT TEMPERATURE DATA
FOR MAXES AND MINS THROUGH THE PERIOD. AS FOR POPS...ENDED UP SIMILAR
TO A BLEND OF THE GUIDANCE TODAY BUT WENT ABOVE ALL OF IT FOR THE
LIGHT RAIN AND SNOW CHANCES LATER THIS EVENING AND THE FIRST PART OF
TONIGHT...MONDAY WAS KEPT DRY IN LINE WITH ALL THE MOS.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 428 PM EST SAT JAN 3 2015
THE MODELS ARE IN REASONABLE AGREEMENT UNTIL LATE IN THE PERIOD. THE
MAIN ISSUE WILL BE A COUPLE OF SURGES OF COLD AIR...ALTHOUGH A BIT
OF LIGHT PRECIP CAN NOT BE RULED OUT. THE COLDEST PART OF THE FIRST
SURGE WILL BE MOVING INTO THE REGION ON MONDAY. WITH UPSLOPE FLOW
AND FORECAST SOUNDINGS SHOWING A SHALLOW MIXED LAYER WITH SATURATION
REACHING TO -10C...A FEW LINGERING FLURRIES WILL BE POSSIBLE EARLY
MONDAY. A CLIPPER TYPE SYSTEM CARRIED ALONG BY RAPID FLOW ALOFT IS
EXPECTED TO PASS NORTH OF THE OHIO RIVER ON TUESDAY. PRECIP WITH
THIS IS LIKELY TO STAY TO OUR NORTH...BUT WITH THE CLOSE PROXIMITY
AND AN ALLOWABLE MARGIN OF ERROR...HAVE CARRIED A SLIGHT CHANCE OF
SNOW IN OUR EXTREME NORTH. THE PASSAGE OF THIS SYSTEM WILL MAKE WAY
FOR THE SECOND SURGE OF COLD AIR...THE COLDEST OF THE SEASON SO FAR.
THE ONSLAUGHT BEGINS BY TUESDAY NIGHT AND CONTINUES INTO WEDNESDAY
NIGHT. THE COLD AIR ADVECTION SHOULD RESULT IN FALLING TEMPS DURING
THE DAY WEDNESDAY. BY THURSDAY MORNING...READINGS SHOULD BE NEAR
ZERO...WITH COLDER VALLEYS PROBABLY BELOW ZERO. DESPITE SOME
SUNSHINE ON THURSDAY...ONLY A LIMITED RECOVERY IS FORECAST IN THE
ARCTIC AIR MASS...WITH SOME LOCATIONS NOT GETTING OUT OF THE TEENS.
IT WILL STILL BE VERY COLD ON THURSDAY NIGHT...BUT NOT AS EXTREME AS
WARM AIR ADVECTION GETS UNDERWAY. THE ECMWF AND GFS START TO SHOW
SIGNIFICANT DIFFERENCES BY NEXT SATURDAY AS A MID/UPPER LEVEL WAVE
DROPS ESE INTO THE CONUS. THE GFS DEVELOPS A SURFACE SYSTEM WHICH
MOVES IN FROM THE WEST WITH LIGHT PRECIP... WHILE THE ECMWF SHOWS
LITTLE SURFACE DEVELOPMENT. IT IS A LOW CONFIDENCE FORECAST BY NEXT
WEEKEND...AND HAVE CARRIED SLIGHT CHANCE POPS ON SATURDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1255 AM EST SUN JAN 4 2015
THE COLD FRONT WILL START TO PUSH EAST ACROSS THE AREA AT A QUICKER
PACE SOON AS THE LOW PRESSURE CENTER NORTH OF KENTUCKY FURTHER
DEEPENS. THE LOCALLY HEAVY RAIN IS NOW CONFINED TO THE EASTERN
PORTION OF THE AREA AND IS SHIFTING EAST...AS WELL. THE LINGERING
RAIN OVER THE AREA WILL REDUCE VISIBILITIES AT TIMES PARTICULARLY
WHEN SOME PATCHY FOG MOVES OVER THE TAF SITES. WITH THE HEAVIER RAINS
NOW SHIFTING EAST OF THE TAF SITES...CIGS WILL MAINLY BE IN THE LOW
AND MID REACHES OF THE VFR CATEGORY. THE STEADY RAIN WILL END BEFORE
DAYBREAK AT MOST SPOTS...BUT ANOTHER DISTURBANCE COULD BRING A FEW
RAIN SHOWERS BY THE MIDDLE OF THE AFTERNOON AND INTO THE EVENING
HOURS. THIS WILL SEND LOWER CIGS BACK INTO THE AREA...AS WELL. WITH
900MB WINDS AROUND 50 KNOTS...LLWS WILL REMAIN A CONCERN INTO SUNDAY
MORNING. AS THE FRONT EXITS SUNDAY...WINDY CONDITIONS WILL LIKELY
DEVELOP BY LATE MORNING FROM THE WEST TO NORTHWEST...CONTINUING
THROUGH THE AFTERNOON HOURS AS WINDS GUST UP TO 25 KNOTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...HAL
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
252 AM EST Sun Jan 4 2015
.SHORT TERM (Now through Monday)...
Issued at 230 AM EST Sun Jan 4 2015
Big weather changes are in store during the short term period as a
strong storm system continues to cross the Ohio Valley. As of 230
am, the latest water vapor imagery and 500 mb RAP heights shows
intense southwesterly flow remaining across the forecast area as the
main shortwave trough lifts through Missouri into northern Illinois.
A secondary PV anomaly is crossing through Oklahoma. At the surface,
a cold front is beginning to move into the LMK CWA. Ahead of this
boundary, conditions are very mild as readings have help up in the
upper 50s to near 60 degrees.
Plan on scattered rain showers and/or drizzle to persist through
the early morning hours, ending southwest to northeast as the main
upper level forcing lifts into Ohio. Then, for the remainder of
this morning, we`ll be under the influence of a dry slot, waiting
for the aforementioned secondary PV anomaly to pivot across the
Ohio Valley this afternoon. 04.00z guidance still shows a good
amount of PV advection with this wave, low level lapse rates
approaching 8-9C/km and weak instability. Meso-models depict
intermittent convective rain showers developing this afternoon and
some of the perkier ones may be strong enough to mix down gusty
winds 30-35 mph. As temperatures aloft crash and reach -10C, there
will be a brief window where precipitation may changeover to snow
showers, especially north of KY parkways. A quick dusting is
possible on grassy surfaces but overall not expecting any impacts.
High temperatures will occur this morning, then plan on readings to
steadily fall throughout the day, reaching the mid 30s to lower 40s
by mid/late afternoon. Combined with a brisk west wind 10-20 mph and
wind chills will be in the 20s by this evening. Quite a change in 24
hours.
As the new work and school week begins Monday morning, a fresh surge
of Arctic air will have taken hold of the forecast area. Plan on
morning temperatures in the teens to lower 20s. A steady
north/northwest wind will make it feel more like +5 to +10F. High
temperatures will be 15 to 20 degrees below normal, struggling to
reach the upper 20s.
.LONG TERM (Monday Night through Saturday)...
Issued at 248 AM EST Sun Jan 4 2015
...Very Cold Temperatures and Wind Chills Mid-Week...
A small, weakening area of low pressure will zip quickly by to our
north early Tuesday morning. Models have been fairly consistent and
continue to be in decent agreement with this feature, taking the
great majority of its associated precipitation to our north through
Illinois, central/northern Indiana, and Ohio. The best chance for
any dusting in the LMK CWA would be north of a Paoli-Madison line,
with scattered flurries possible as far south as the Interstate 64
corridor. Atmospheric cross-sections continue to show a good amount
of dry air in the low levels, even in the far north of the LMK CWA,
lending credence to the idea that there will be minimal impact here.
A very impressive dome of frigid high pressure will invade from the
northwest behind Tuesday`s system. This high, already very cold to
begin with, will slide across extensive snowpack in the Plains and
Midwest on its way to the Ohio and Tennessee Valleys, limiting
moderation of the airmass. On Wednesday, sunrise temperatures
should be in the teens, and will fall from there into the single
digits in Indiana and the lower and middle teens in Kentucky by
suppertime. Winds will be brisk and gusty in a tight pressure
gradient on the nose of the incoming high, possibly gusting to
around 20 mph as temperatures fall. Wind chills Wednesday afternoon
and evening over southern Indiana and northern Kentucky will be in
the -5 to -15 range.
By dawn on Thursday the center of the high will be right over us.
Any breeze will be light, and what breeze there is may be coming in
from the northwest off the Midwestern snow field. Skies should be
clear. So, very cold temperatures can be expected. Southern
Indiana locations will dip slightly below zero, with lows around
zero in Kentucky all the way down to the Tennessee border.
A weakening cold front will pass through on Friday morning
completely dry with high pressure centers ahead of and behind it,
blocking any moisture supply. Then, behind the departing front,
another Canadian high for Friday night/Saturday.
&&
.AVIATION (06Z TAF Update)...
Issued at 1210 AM EST Sun Jan 4 2015
As of 05z, all TAF sites remain ahead of surface cold front
which lies along the IN/IL border south through far western KY and
TN. The front is slated to cross through the state over the next few
hours noted by a wind shift to the southwest. Ahead of this
boundary, there is a batch of MVFR ceilings with pockets of VFR
around LEX and isolated IFR to the west of BWG. Expecting
predominately low-end MVFR /1200 to 1500 ft/ ceilings through the
morning hours but could not rule out a period of 800-1000 ft
ceilings at BWG/SDF in the early pre-dawn hours. Rain showers will
become more drizzle, especially at SDF/BWG. Visibilities along and
behind the front vary from 1-3 sm, worse in drizzle. Tried to time
this activity coming through BWG/SDF but observations have been
bouncing around the last few hours so showed a general trend.
A dry slot looks to end precipitation for the mid morning hours, but
an upper level feature along with steepening lapse rates will result
in scattered rain showers by late morning and for much of the
afternoon hours. The main impact will be west winds mixed down as
guidance points to near 25 kt gusts. Rain showers may transition to
or mix with snow showers at SDF toward the late afternoon/evening
hours. Saturation in the lowest levels will keep MVFR ceilings in
place through the period, though conditions should improve toward
the end of the current TAF period.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Short Term........ZBT
Long Term.........13
Aviation..........ZBT
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
111 AM EST SUN JAN 4 2015
.UPDATE...
ISSUED AT 110 AM EST SUN JAN 4 2015
THE FORECAST IS ON TRACK FOR THE REST OF THE NIGHT AS THE HEAVIER
RAIN TAPERS OFF IN THE EAST WHILE THE STEADY RAIN WILL COME TO AN END
FROM WEST TO EAST THROUGH THE NEXT SEVERAL HOURS. MADE ONLY MINOR
ADJUSTMENTS TO THE POP AND WX PATTER INTO SUNDAY MORNING BASED ON
RADAR TRENDS AND THE LATEST HRRR/NAM12 GUIDANCE. ALSO FINE TUNED THE
T AND TD GRIDS PER THE CURRENT OBS...TRENDS...AND BCCONSSHORT
GUIDANCE. THESE UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 909 PM EST SAT JAN 3 2015
UPDATED THE FORECAST TO REMOVE THUNDER. ALL THE LIGHTNING AS BEEN
BOTTLED UP WELL TO OUR SOUTH AND BASED ON TRAJECTORIES...IT JUST
WON`T MAKE IT THIS FAR NORTH. WITH THIS SAID...HEAVIER RAIN THREAT
SEEMS TO BE DIMINISHING AS HRRR AND RAP ARE SHOWING A FASTER
PROGRESSION OF THE PRECIPITATION THROUGH THE AREA OVERNIGHT. IN
FACT...IT LOOKS LIKE RAIN COULD BE MOVING OUT AS EARLY AS 4 OR 5 AM.
WITH RAINFALL RATES AT BEST AROUND A QUARTER OF AN INCH PER
HOUR...REALLY DON`T SEE MUCH OF A HEAVY RAIN THREAT REMAINING. THE
WIND THREAT REMAINS FOR THE HIGHER ELEVATIONS AS VAD WIND PROFILE
CONTINUES TO SHOW 35 TO 40 MPH WINDS JUST OFF THE SURFACE.
UPDATE ISSUED AT 712 PM EST SAT JAN 3 2015
COLD FRONT HAS NOW CROSSED WESTERN KENTUCKY. AMPLE MOISTURE IS
PUSHING NORTHWARD AHEAD OF THE FRONT OVER THE LOWER MISSISSIPPI RIVER
VALLEY. THIS RAIN IS EXPECTED TO OVERSPREAD EASTERN KENTUCKY OVER THE
NEXT 2 TO 4 HOURS. VERY COLD CLOUD TOPS ASSOCIATED WITH THIS ACTIVITY
WILL KEEP THE THREAT OF THUNDER IN THE FORECAST THROUGH THIS EVENING.
HOWEVER...LATEST HI-RES MODEL GUIDANCE SUGGEST THE THUNDER THREAT
MAY EXIT AROUND MIDNIGHT AS THE FRONT SLOWS OVER THE AREA.
HOWEVER...RAIN WILL LIKELY PERSIST THROUGH THE NIGHT...BEFORE
TAPERING OFF FROM WEST TO EAST TOWARDS DAYBREAK. PRECIPITABLE WATER
REMAIN AROUND 1.4 TONIGHT WHICH IS NEAR THE 99TH PERCENTILE FOR EARLY
JANUARY. THIS WILL KEEP THE THREAT OF LOCALLY HEAVY RAIN IN THE
FORECAST OVERNIGHT. NOT TOO CONCERNED ABOUT THE 1 HOUR FLASH FLOOD
GUIDANCE AS WE WON`T LIKELY SEE THIS KIND OF RAINFALL TONIGHT.
HOWEVER...THE 3 HOUR FLASH FLOOD GUIDANCE IS JUST UNDER 2 INCHES IN
SOME PLACES...SO WE WILL HAVE TO WATCH FOR SOME MINOR FLOODING
POTENTIAL TONIGHT. CERTAINLY PONDING ON ROADS WILL BE AN ISSUE DUE TO
THE HEAVY NATURE OF THE RAIN. ADJUSTED POPS AND WEATHER TO ALLOW FOR
A BRIEF LULL BEFORE THE RAIN ARRIVES THIS EVENING. ALSO ADJUSTED
TEMPERATURES TO SHOW A STEADY TEMPERATURE CURVE THROUGH THE NIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 332 PM EST SAT JAN 3 2015
AN UPPER LEVEL LOW...CURRENTLY OVER THE NORTH TEXAS PANHANDLE...WILL
CONTINUE TO SHIFT NE THIS EVENING AND OVERNIGHT...GRAZING THE
WESTERN PORTION OF THE STATE BEFORE MERGING INTO THE NORTHERN STREAM
AND LOSING CONSIDERABLE STRENGTH. MEANWHILE...MUCH OF KY WILL
EXPERIENCE STRONG SW TO NE FLOW THROUGH THE DAY SUNDAY...AS LONGWAVE
TROUGHING TAKES HOLD ACROSS MUCH OF THE CENTRAL CONUS. THE AXIS OF
THIS TROUGH IS EXPECTED TO REACH EASTERN KY BY SUNDAY
EVENING...WHERE IT WILL REMAIN STATIONARY THROUGH SUNDAY NIGHT WITH
IMPRESSIVELY STRONG PRESSURE GRADIENTS EXPECTED ACROSS THE OHIO
RIVER AND TENNESSEE VALLEY REGIONS.
CURRENTLY...A WARM FRONT HAS JUST PASSED FROM NORTH TO SOUTH ACROSS
MUCH OF KY...EXTENDING FROM A SURFACE LOW PRESSURE SYSTEM WHICH IS
SITTING OVER SOUTHERN ILLINOIS. THIS HAS ALLOWED VERY UNSEASONABLY
WARM TEMPERATURES TO FLOW INTO THE CWA...SUCH AS 64 DEGREES HERE AT
THE NWS OFFICE...67 AT QUICKSAND...AND 68 DEGREES AT WHITESBURG. THE
STRONG LOW LEVEL INVERSION THAT WAS IN PLACE JUST AHEAD OF THIS WARM
FRONT /AS STRONG OVERRUNNING WAS TAKING PLACE EARLIER IN THE DAY/ IS
NOW STARTING TO SUBSIDE...THUS ALLOWING STRONG SSW WINDS TO BEGIN
REACHING THE GROUND. PRECIP IS ALSO CONTINUING TO FILTER INTO THE
REGION FROM THE SW...CURRENTLY SCT TO WIDESPREAD RAIN IS FALLING
ACROSS THE REGION. WE HAVE HAD A FEW LIGHTNING STRIKES WITH THE
CONVECTION LATE THIS MORNING...SO KEPT MENTION OF THUNDER GOING IN
THE FORECAST FOR THE DAY. EXPECT ANY HEAVY SHOWERS TO RESULT IN WIND
GUSTS BETWEEN 20 AND 30MPH THROUGH THE REST OF THE AFTERNOON.
IN ADDITION TO ALL OF THIS...A COLD FRONT IS CURRENTLY EXTENDING
SOUTHWARD FROM THE LOW...JUST WEST OF KY. AS THE SURFACE LOW
CONTINUES TO LIFT TO THE NE THIS EVENING AND OVERNIGHT...THIS COLD
FRONT WILL SLOWLY PROGRESS EASTWARD. THE LATEST GFS40 MODEL IS
PROJECTING THE PASSAGE OF THE FRONT ACROSS EASTERN KY BETWEEN 6Z
/WEST/ AND 12Z /EAST/ OVERNIGHT TONIGHT. IT IS ALONG AND JUST AHEAD
OF THIS COLD FRONT THAT THE HEAVIEST RAIN AND ISOLATED THUNDERSTORMS
ARE ONGOING...CURRENTLY SPANNING FROM MEMPHIS TO WESTERN OHIO. THIS
CONVECTION WILL MAKE IT/S WAY INTO OUR CWA AND MOVE FROM WEST TO
EAST THIS EVENING AND THROUGH THE OVERNIGHT HOURS TONIGHT. GIVEN THE
WIDESPREAD CLOUD COVER AND PRECIP THAT WILL LIKELY OCCUR...WENT MUCH
HIGHER THAN THE MOS FOR OVERNIGHT LOW TEMPERATURES. WOULDN/T BE
SURPRISED IF WE STAY WELL IN THE 50S FOR LOWS. MODELS ARE STILL IN
GOOD AGREEMENT AND SHOW GOOD CONSISTENCY...SO NO DRASTIC CHANGES
WERE MADE TO THE PREVIOUS FORECAST FOR TIMING AND PRECIP AMOUNTS AS
THE PREFRONTAL/FRONTAL PRECIP MOVES THROUGH THE AREA TONIGHT. KEPT
OVERNIGHT QPF BETWEEN AN INCH AND AN INCH AND A QUARTER AT MOST
LOCATIONS.
STRONG WINDS ALOFT AS A RESULT OF THE TIGHT PRESSURE GRADIENTS WILL
CONTINUE TO MIX DOWN WITH ANY OF THE HEAVIER SHOWERS/THUNDERSTORMS
THIS AFTERNOON AND EVENING. EXPECT THESE WINDS TO INCREASE ALONG AND
JUST BEHIND THE COLD FRONT. ONCE THE COLD FRONT PASSES THROUGH...AN
IMPRESSIVE BLAST OF DRY AIR WILL QUICKLY MOVE INTO THE REGION WITH
WINDS SHIFTING TO A MORE WRLY DIRECTION. ALTHOUGH SOME WRAP AROUND
MOISTURE WILL BE POSSIBLE WITH THIS SYSTEM DURING THE DAY
SUNDAY...QPF AMOUNTS WILL BE DRASTICALLY REDUCED WITH ANY PRECIP
THAT DOES OCCUR. COLDER AIR FILTERING INTO THE REGION BEHIND THE
COLD FRONT WILL KEEP TEMPERATURES FALLING THROUGHOUT THE DAY SUNDAY.
BY SUNDAY NIGHT...TEMPS WILL DROP WELL BELOW FREEZING. THEREFORE...IT
IS POSSIBLE THAT SOME SNOW MAY MIX WITH THE RAIN AS IT TAPERS OFF
SUNDAY NIGHT. ANY REMAINING SHALLOW MOISTURE WILL BE CAUGHT IN AN
UPSLOPE FLOW PATTERN LATE SUNDAY NIGHT...WITH TEMPS FALLING TO -10C
OR LOWER ACCORDING TO THE LATEST FORECAST SOUNDINGS. AS
SUCH...CONTINUED MENTION OF FLURRIES IN THE SE SUNDAY
NIGHT...EXPANDING IN COVERAGE AS TEMPERATURES CONTINUE TO FALL BELOW
-10C ALOFT.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 428 PM EST SAT JAN 3 2015
THE MODELS ARE IN REASONABLE AGREEMENT UNTIL LATE IN THE PERIOD. THE
MAIN ISSUE WILL BE A COUPLE OF SURGES OF COLD AIR...ALTHOUGH A BIT
OF LIGHT PRECIP CAN NOT BE RULED OUT. THE COLDEST PART OF THE FIRST
SURGE WILL BE MOVING INTO THE REGION ON MONDAY. WITH UPSLOPE FLOW
AND FORECAST SOUNDINGS SHOWING A SHALLOW MIXED LAYER WITH SATURATION
REACHING TO -10C...A FEW LINGERING FLURRIES WILL BE POSSIBLE EARLY
MONDAY. A CLIPPER TYPE SYSTEM CARRIED ALONG BY RAPID FLOW ALOFT IS
EXPECTED TO PASS NORTH OF THE OHIO RIVER ON TUESDAY. PRECIP WITH
THIS IS LIKELY TO STAY TO OUR NORTH...BUT WITH THE CLOSE PROXIMITY
AND AN ALLOWABLE MARGIN OF ERROR...HAVE CARRIED A SLIGHT CHANCE OF
SNOW IN OUR EXTREME NORTH. THE PASSAGE OF THIS SYSTEM WILL MAKE WAY
FOR THE SECOND SURGE OF COLD AIR...THE COLDEST OF THE SEASON SO FAR.
THE ONSLAUGHT BEGINS BY TUESDAY NIGHT AND CONTINUES INTO WEDNESDAY
NIGHT. THE COLD AIR ADVECTION SHOULD RESULT IN FALLING TEMPS DURING
THE DAY WEDNESDAY. BY THURSDAY MORNING...READINGS SHOULD BE NEAR
ZERO...WITH COLDER VALLEYS PROBABLY BELOW ZERO. DESPITE SOME
SUNSHINE ON THURSDAY...ONLY A LIMITED RECOVERY IS FORECAST IN THE
ARCTIC AIR MASS...WITH SOME LOCATIONS NOT GETTING OUT OF THE TEENS.
IT WILL STILL BE VERY COLD ON THURSDAY NIGHT...BUT NOT AS EXTREME AS
WARM AIR ADVECTION GETS UNDERWAY. THE ECMWF AND GFS START TO SHOW
SIGNIFICANT DIFFERENCES BY NEXT SATURDAY AS A MID/UPPER LEVEL WAVE
DROPS ESE INTO THE CONUS. THE GFS DEVELOPS A SURFACE SYSTEM WHICH
MOVES IN FROM THE WEST WITH LIGHT PRECIP... WHILE THE ECMWF SHOWS
LITTLE SURFACE DEVELOPMENT. IT IS A LOW CONFIDENCE FORECAST BY NEXT
WEEKEND...AND HAVE CARRIED SLIGHT CHANCE POPS ON SATURDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1255 AM EST SUN JAN 4 2015
THE COLD FRONT WILL START TO PUSH EAST ACROSS THE AREA AT A QUICKER
PACE SOON AS THE LOW PRESSURE CENTER NORTH OF KENTUCKY FURTHER
DEEPENS. THE LOCALLY HEAVY RAIN IS NOW CONFINED TO THE EASTERN
PORTION OF THE AREA AND IS SHIFTING EAST...AS WELL. THE LINGERING
RAIN OVER THE AREA WILL REDUCE VISIBILITIES AT TIMES PARTICULARLY
WHEN SOME PATCHY FOG MOVES OVER THE TAF SITES. WITH THE HEAVIER RAINS
NOW SHIFTING EAST OF THE TAF SITES...CIGS WILL MAINLY BE IN THE LOW
AND MID REACHES OF THE VFR CATEGORY. THE STEADY RAIN WILL END BEFORE
DAYBREAK AT MOST SPOTS...BUT ANOTHER DISTURBANCE COULD BRING A FEW
RAIN SHOWERS BY THE MIDDLE OF THE AFTERNOON AND INTO THE EVENING
HOURS. THIS WILL SEND LOWER CIGS BACK INTO THE AREA...AS WELL. WITH
900MB WINDS AROUND 50 KNOTS...LLWS WILL REMAIN A CONCERN INTO SUNDAY
MORNING. AS THE FRONT EXITS SUNDAY...WINDY CONDITIONS WILL LIKELY
DEVELOP BY LATE MORNING FROM THE WEST TO NORTHWEST...CONTINUING
THROUGH THE AFTERNOON HOURS AS WINDS GUST UP TO 25 KNOTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...JMW
LONG TERM...HAL
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
334 AM EST SUN JAN 4 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 335 PM EST SAT JAN 3 2015
UPPER MICHIGAN IS CURRENTLY BETWEEN THE STRONGER AND PRECIPITATION
PRODUCING SURFACE/UPPER LEVEL FEATURES. THE REMNANTS OF THE SURFACE
LOW THAT MOVED THROUGH MINNESOTA LAST NIGHT HAS LEFT A SURFACE
TROUGH OVER WESTERN LAKE SUPERIOR THIS AFTERNOON. ON THE NORTHWEST
SIDE OF THAT TROUGH...SNOW HAS BEEN FALLING FOR MUCH OF THE DAY IN
THE MINNESOTA ARROWHEAD IN ASSOCIATION WITH THE MID LEVEL Q-VECTOR
CONVERGENCE AND THE RIGHT REAR OF THE SPLIT NORTHERN STREAM JET
STREAK. FARTHER SOUTH...WATER VAPOR IMAGERY SHOWS A STRONG UPPER
WAVE LIFTING NORTHEAST OUT OF THE SOUTHERN PLAINS...WHILE A SECOND
WEAKER WAVE IS NEARING IT FROM THE NORTHWEST IN COLORADO. BETWEEN
THESE TWO FEATURES AND BEHIND THE SHORTWAVE THAT MOVED THROUGH
SOUTHEAST UPPER MICHIGAN LAST NIGHT AND THIS MORNING (PRODUCING
1-1.5IN OF SNOW NEAR LAKE MICHIGAN)...CLOUDY SKIES PREVAIL OVER
UPPER MICHIGAN. THIS IS DUE TO THE LINGERING LOW LEVEL MOISTURE
TRAPPED BELOW THE DRYING ALOFT BEHIND THE SHORTWAVE. ONCE THE DEEPER
MOISTURE DEPARTED WITH THE SHORTWAVE...SAW A TRANSITION TO BR AND
REDUCED VISIBILITIES ON THE AUTOMATED STATIONS. CALLING AROUND TO
THE SOUTHERN PART OF THE CWA HAS SHOWN A TRANSITION FROM WEST TO
EAST ALONG THE WISCONSIN BORDER TO FREEZING DRIZZLE OVER THE LAST
COUPLE OF HOURS. FARTHER NORTH AT OUR OFFICE...WE HAVE BEEN JUST
SEEING A FEW FLURRIES DUE TO CLOUD LAYER BEING RIGHT AT THE EDGE OF
THE MORE FAVORABLE ICE CRYSTAL REGION. EXPECT THIS
BORDERLINE/LIMITED CONDITION TO CONTINUE OVER THE SOUTH CENTRAL AND
SOUTHEASTERN CWA INTO THE EVENING HOURS AND WILL SHOW THE POTENTIAL
FOR FREEZING DRIZZLE IN THE FORECAST. WILL ISSUE AN SPS TO
HIGHLIGHT THE FREEZING DRIZZLE AND UNTREATED ROADS BECOMING
SLIPPERY FOR THE AREAS NOT CURRENTLY COVERED BY THE ADVISORY.
OTHERWISE...EXPECT THE FREEZING DRIZZLE TO DIMINISH FROM WEST TO
EAST THIS EVENING AS THE DEEPER MOISTURE FROM THE FEATURE OVER
WESTERN LAKE SUPERIOR MOVES OVER THE U.P. TONIGHT.
THE STRONG TROUGH IN THE SOUTHERN PLAINS WILL LIFT NORTHEAST
THROUGH THE LOWER GREAT LAKES REGION TONIGHT...STRENGTHENING A LOW
FROM 1007MB OVER SOUTHERN ILLINOIS TO 998MB BETWEEN LAKE
ERIE/ONTARIO AT 12Z SUNDAY. AS THAT OCCURS...THE MID LEVEL TROUGH
ASSOCIATED WITH THE SURFACE TROUGH OVER THE WESTERN LAKE WILL
DROP SOUTHEAST ACROSS UPPER MICHIGAN THROUGH SUNDAY MORNING. THE
SYNOPTIC LIQUID EQUIVALENT PRECIPITATION (TIED TO THE 850-650MB
FGEN) LOOKS TO BE IN THE 0.10-0.15 INCH RANGE FOR MOST OF THE CWA
THROUGH SUNDAY MORNING. SNOW RATIOS INITIALLY WILL LIKELY BE AROUND
10-15 TO 1 AS THERE IS STILL A PERIOD OF THE CLOUD BEING ABOVE/BELOW
THE DGZ. BUT THERE WILL LIKELY BE A TRANSITION TO A BRIEF (2-4HR)
PERIOD LATE TONIGHT INTO SUNDAY MORNING WHEN THE LOWEST 10-12KFT OF
THE ATMOSPHERE IS WITHIN THE DGZ. THIS WOULD LEAD TO A PERIOD OF
FLUFFIER SNOW AND RATIOS RISING TOWARDS OR EVEN ABOVE 20-1. DON/T
FEEL COMFORTABLE GOING MUCH ABOVE THAT DUE TO THE FORCING THAT IS
EXPECTED ABOVE THE DGZ. THUS...SYNOPTIC SNOW WOULD AMOUNT TO
1 TO 2.5-3.0 INCHES...WITH THE GREATEST OVER THE WEST HALF. BUT AS
IS NORMALLY THE CASE WITH LAKE SUPERIOR AND OUR TERRAIN
INFLUENCES...THAT ISN/T THE COMPLETE STORY ON THE SNOWFALL.
MUCH COLDER AIR WILL SURGE INTO THE AREA TONIGHT BEHIND THE
850-700MB TROUGH...WITH 850MB TEMPS FALLING FROM 19Z RAP ANALYZED
OF -5C TO -7C TO -19C EAST AND -24C WEST BY 18Z SUNDAY. THIS WILL
LEAD TO LAKE ENHANCEMENT DEVELOPING FROM WEST TO EAST TONIGHT AND
THEN TRANSITIONING TO PURE LAKE EFFECT AS THE DEEPER MOISTURE
DEPARTS ON SUNDAY. THE HELP FROM THE LAKE WILL BE FOCUSED IN THE
NORTHERLY WIND LOCATIONS OF THE WEST AND NORTH CENTRAL TONIGHT AND
THEN WINDS BACK TO THE NORTHWEST SUNDAY MORNING AND WEST-NORTHWEST
BY SUNDAY EVENING. WITH THAT COLD AIR SURGING IN...THE CLOUD LAYER
ON SUNDAY WILL TRANSITION TO BEING ABOVE THE DGZ. THUS...WOULD
EXPECT A TRANSITION OF THE SNOWFLAKES TO COLUMNS/PLATES AND LOWER
SNOW RATIOS BELOW 20-1. CONTINUED THE TREND TOWARDS THE HIGH
RESOLUTION MODELS FOR QPF AMOUNTS TONIGHT/SUNDAY IN THE
LAKE/TERRAIN ENHANCED AREAS (0.25-0.40 IN). THIS LEADS TO SNOWFALL
AMOUNTS OF 3-5 INCHES OF SNOW TONIGHT OVER THE FAVORED NORTH WIND
AREAS OVER THE WEST AND NORTH CENTRAL. THERE COULD BE SOME
LOCALIZED HIGHER AMOUNTS TOWARDS 5.5-6.0 INCHES. THE LOWERING RATIOS
ON SUNDAY WILL LEAD TO LOWER AMOUNTS OVER THE WEST...BUT COULD
STILL SEE 2-5 INCHES IN THE FAVORED NORTHWEST WINDS AREAS OVER THE
EAST. IN ADDITION TO THE SNOW...WINDS WILL QUICKLY INCREASE FROM
NORTHWEST TO SOUTHEAST TONIGHT...WITH GUSTS BETWEEN 30 TO 45 MPH
(HIGHEST NEAR LAKE SUPERIOR). THAT WILL LEAD TO BLOWING SNOW AND
COMBINED WITH THE EXPECTED SNOW...SHOULD SEE VISIBILITIES
FREQUENTLY REDUCED BELOW ONE MILE OVER THE NORTHERN HALF OF THE
CWA. THUS...THINK THE GOING ADVISORY LOOKS GOOD WITH THE FORECASTED
SNOWFALL AMOUNTS AND IMPACT WITH THE REDUCED VISIBILITIES FROM
BLOWING SNOW. AS MENTIONED ABOVE...THINK SOME HIGHER TERRAIN
LOCATIONS FLIRTING WITH 12HR WARNING SNOWFALL AMOUNTS (DUE TO THE
OVERALL AVERAGE SNOW RATIO BEING JUST BELOW OUR LAKE EFFECT WARNING
CRITERIA). BUT WITH MUCH OF THE SNOW FALLING ON A WEEKEND
OVERNIGHT AND THE EXPECTED COVERAGE FAIRLY LOCALIZED...WILL KEEP
THE ADVISORY IN PLACE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 330 AM EST SUN JAN 4 2015
SOMEWHAT REPETITIOUS PATTERN THIS WEEK AS WE WILL SEE THREE SURGES
OF COLD AIR...WITH SFC RIDGING BETWEEN THESE SURGES. PATTERN LOOKS
TO POSSIBLY MODIFY FRI INTO NEXT WEEKEND...BUT MODEL DIFFERENCES
KEEPS CONFIDENCE IN THIS OCCURRING LOW. OTHERWISE...CONFIDENCE IS
GOOD MON THROUGH THU NIGHT.
12Z MON WILL BE A VERY COLD START TO A VERY COLD DAY AS THE FIRST
BLAST OF COLD AIR WILL BE OVER THE AREA. HIGH TEMPS MON ARE ONLY
EXPECTED TO RANGE FROM 10F AT COPPER HARBOR AND FROM GRAND MARAIS E
TO AROUND -5F OVER THE INTERIOR W HALF OF UPPER MI. WIND CHILLS AT
18Z MON ARE EXPECTED TO RANGE FROM -15F E TO -25F W. NW WIND LES
WILL BE ONGOING...BUT WILL WEAKEN AND BECOME CONFINED TO THE
KEWEENAW AND FAR NERN UPPER MI LATE IN THE DAY INTO MON NIGHT AS A
SFC RIDGE MOVES THROUGH AHEAD OF SFC TROUGH MOVING IN FROM THE NW. A
CLIPPER ALSO LOOKS TO MOVE S OF THE CWA...KEEP ALL OR MOST OF THE
PRECIP FROM THE SYSTEM S OF THE CWA. THE VERY COLD AIR WILL MEAN THE
IDEAL DGZ WILL NOT BE TAPPED INTO AND SNOWFLAKE SIZE WILL BE QUITE
SMALL...WHICH WILL RESULT IN VIS REDUCTIONS IN LES AREAS.
ALSO...WINDS WILL BE GUSTY NEAR LAKE SUPERIOR ON MON...LEADING TO
FURTHER VIS REDUCTIONS...ESPECIALLY OVER THE KEWEENAW PENINSULA. NOT
LOOKING AT ANYTHING MORE THAN NUISANCE SNOWFALL AMOUNTS GIVEN
BACKING FLOW WITH TIME AND LOW SNOW TO LIQUID RATIOS. LOWS MON NIGHT
WILL RANGE FROM THE LOW SINGLE DIGITS ABOVE ZERO ALONG PARTS OF THE
LAKE SUPERIOR SHORE TO AROUND -15F INTERIOR W AND CENTRAL.
LOW LEVEL WINDS TURN NWLY AGAIN TUE INTO EARLY WED AS THE SECOND
COLD WAVE MOVES THROUGH. EXPECT AN UPTICK IN LES IN NW WIND
SNOWBELTS...WITH INCREASED WINDS/BLOWING SNOW. COULD SEE ADVISORY
LEVEL EVENT TUE INTO EARLY WED AS FLOW WILL BE MORE CONSTANT...WITH
THE MAIN HAZARD BEING REDUCED VIS DUE TO LOW SLR AND BLOWING SNOW.
SNOW ACCUMULATIONS WILL BE GREATER THAN ON MONDAY...BUT WILL STILL
BE LIMITED BY THE SMALL FLAKE SIZE. TUE WILL BE WARMER WITH HIGHS
MOSTLY IN THE SINGLE DIGITS ABOVE ZERO. LOW TUE NIGHT WILL BE
SIMILAR TO MON NIGHT. HIGH TEMPS ON WED LOOK SIMILAR TO MON.
ANOTHER RIDGE MOVES THROUGH LATE WED INTO EARLY THU...PUSHING LES
INTO MORE NRN PORTIONS OF THE CWA.
MODELS DEPICT ANOTHER CLIPPER MOVING INTO THE REGION...BUT THIS TIME
ACROSS THE CWA. ONLY MINOR SNOWFALL AMOUNTS ARE EXPECTED WITH THE
CLIPPER AS MODEL QPF IS GENERALLY LESS THAN 0.10 INCHES.
HOWEVER...BEHIND THE CLIPPER IS THE THIRD WAVE OF COLD AIR AND NW
LOW LEVEL WINDS. LES WILL INCREASE IN NW WIND SNOWBELTS BEHIND THE
CLIPPER AND CONTINUE AT LEAST INTO FRI. SLR VALUES AND GUSTY
WINDS/BLOWING SNOW EXPECTED AGAIN. VIS REDUCTIONS REMAIN THE
GREATEST THREAT.
AS MENTIONED EARLIER...CONFIDENCE IS LOWER FRI AND SAT DUE TO POOR
RUN TO RUN CONTINUITY AND MODEL DISAGREEMENT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1149 PM EST SAT JAN 3 2015
WITH GUSTY N TO NW WINDS/BLSN AND SNOW SHOWERS...EXPECT LIFR
CONDITIONS TO PREVAIL OVERNIGHT AT KIWD/KCMX. CONDITIONS AT KIWD
WILL IMPROVE TO IFR LATE THIS MORNING AND TO MVFR LATE IN THE AFTN
AS WINDS BACK SLOWLY AND PUSH MAJORITY OF LAKE EFFECT SNOW TO JUST N
OF THE TERMINAL. AT KCMX...INCREASINGLY COLDER AIR THRU THE DAY WILL
RESULT IN SNOWFLAKES BECOMING SMALLER AND FINER AND MUCH MORE
EFFECTIVE AT REDUCING VIS. COMBINED WITH GUSTY WINDS/BLSN...KCMX
WILL LIKELY REMAIN LIFR THRU THE MORNING WITH FURTHER REDUCTION TO
VLIFR LIKELY IN THE AFTN AND THRU TONIGHT AS WINDS BACK TO A MORE
FAVORABLE WNW DIRECTION FOR PERSISTENT/HEAVIER SNOW SHOWERS. AT
KSAW...IFR CONDITIONS WILL LIKELY FALL TO LIFR OVERNIGHT AS AREA OF
SNOW MOVES ACROSS THE AREA AND IS ENHANCED BY INCREASING UPSLOPE
WIND OFF THE LAKE. EXPECT IMPROVEMENT TO IFR MID TO LATE MORNING AND
THEN MVFR IN THE AFTN AS WINDS BACK...RESULTING IN DIMINISHED
UPSLOPE FLOW OFF THE LAKE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 335 PM EST SAT JAN 3 2015
THE BUSY MARINE WEATHER WE HAVE HAD RECENTLY WILL CONTINUE WITH
GALES AND HEAVY FREEZING SPRAY RETURNING AND HOISTED GALE WARNINGS
AND HEAVY FREEZING SPRAY WARNINGS FOR LATE TONIGHT INTO SUNDAY. A
COUPLE MORE GALE EVENTS ARE POSSIBLE ON LAKE SUPERIOR TUESDAY NIGHT
AND WEDNESDAY MORNING AND AGAIN FOR THURSDAY NIGHT WITH NORTHWEST
GALES EXPECTED THEN. FREEZING SPRAY WILL ALSO BE A PROBLEM THROUGH
MOST OF THIS FORECAST PERIOD.
WINDS SHIFT TO THE NORTH LATE TONIGHT AS THE NORTHERN PLAINS
TROUGH MERGES WITH ANOTHER LOW PRESSURE SYSTEM LIFTING NORTH OVER
THE CENTRAL GREAT LAKES. NORTH GALES TO 35-40 KTS ARE EXPECTED
SUNDAY ESPECIALLY OVER THE EASTERN HALF OF LK SUPERIOR. HEAVY
FREEZING SPRAY WILL DEVELOP TONIGHT AS ARCTIC AIR POURS OVER
LK SUPERIOR. GALES SHOULD DIMINISH BY LATE SUNDAY NIGHT...BUT NW-W
WINDS TO 30 KTS AND HEAVY FREEZING SPRAY WILL LINGER THROUGH MONDAY.
W-SW WINDS TO 25 KTS ON TUESDAY AS A CLIPPER SYSTEM CROSSES UPPER
GREAT LAKES. BEHIND THE CLIPPER...PLAN ON ANOTHER ROUND OF NW GALES
AND HEAVY FREEZING SPRAY THROUGH WEDNESDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 7 PM EST /6 PM CST/ THIS EVENING
FOR MIZ001>005-009-084.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ006-
007-085.
LAKESHORE FLOOD ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ001>003.
WIND CHILL WATCH FROM THIS EVENING THROUGH MONDAY MORNING FOR
MIZ009>011.
LAKESHORE FLOOD ADVISORY FROM 7 AM THIS MORNING TO 7 PM EST THIS
EVENING FOR MIZ005>007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 AM THIS MORNING TO 1 AM EST
FRIDAY FOR LSZ251-267.
GALE WARNING UNTIL 7 AM EST MONDAY FOR LSZ249>251-267.
HEAVY FREEZING SPRAY WARNING UNTIL 1 AM EST /MIDNIGHT CST/
FRIDAY FOR LSZ162-240>250-263>266.
GALE WARNING UNTIL 7 AM EST /6 AM CST/ MONDAY FOR LSZ240>248-
263>266.
GALE WARNING UNTIL 5 AM EST /4 AM CST/ EARLY THIS MORNING FOR
LSZ162.
LAKE MICHIGAN...
HEAVY FREEZING SPRAY WARNING FROM 7 AM THIS MORNING TO 7 PM EST
THIS EVENING FOR LMZ221-248-250.
GALE WARNING FROM 7 AM THIS MORNING TO 7 PM EST THIS EVENING FOR
LMZ221-248-250.
&&
$$
SHORT TERM...SRF
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1149 PM EST SAT JAN 3 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 335 PM EST SAT JAN 3 2015
UPPER MICHIGAN IS CURRENTLY BETWEEN THE STRONGER AND PRECIPITATION
PRODUCING SURFACE/UPPER LEVEL FEATURES. THE REMNANTS OF THE SURFACE
LOW THAT MOVED THROUGH MINNESOTA LAST NIGHT HAS LEFT A SURFACE
TROUGH OVER WESTERN LAKE SUPERIOR THIS AFTERNOON. ON THE NORTHWEST
SIDE OF THAT TROUGH...SNOW HAS BEEN FALLING FOR MUCH OF THE DAY IN
THE MINNESOTA ARROWHEAD IN ASSOCIATION WITH THE MID LEVEL Q-VECTOR
CONVERGENCE AND THE RIGHT REAR OF THE SPLIT NORTHERN STREAM JET
STREAK. FARTHER SOUTH...WATER VAPOR IMAGERY SHOWS A STRONG UPPER
WAVE LIFTING NORTHEAST OUT OF THE SOUTHERN PLAINS...WHILE A SECOND
WEAKER WAVE IS NEARING IT FROM THE NORTHWEST IN COLORADO. BETWEEN
THESE TWO FEATURES AND BEHIND THE SHORTWAVE THAT MOVED THROUGH
SOUTHEAST UPPER MICHIGAN LAST NIGHT AND THIS MORNING (PRODUCING
1-1.5IN OF SNOW NEAR LAKE MICHIGAN)...CLOUDY SKIES PREVAIL OVER
UPPER MICHIGAN. THIS IS DUE TO THE LINGERING LOW LEVEL MOISTURE
TRAPPED BELOW THE DRYING ALOFT BEHIND THE SHORTWAVE. ONCE THE DEEPER
MOISTURE DEPARTED WITH THE SHORTWAVE...SAW A TRANSITION TO BR AND
REDUCED VISIBILITIES ON THE AUTOMATED STATIONS. CALLING AROUND TO
THE SOUTHERN PART OF THE CWA HAS SHOWN A TRANSITION FROM WEST TO
EAST ALONG THE WISCONSIN BORDER TO FREEZING DRIZZLE OVER THE LAST
COUPLE OF HOURS. FARTHER NORTH AT OUR OFFICE...WE HAVE BEEN JUST
SEEING A FEW FLURRIES DUE TO CLOUD LAYER BEING RIGHT AT THE EDGE OF
THE MORE FAVORABLE ICE CRYSTAL REGION. EXPECT THIS
BORDERLINE/LIMITED CONDITION TO CONTINUE OVER THE SOUTH CENTRAL AND
SOUTHEASTERN CWA INTO THE EVENING HOURS AND WILL SHOW THE POTENTIAL
FOR FREEZING DRIZZLE IN THE FORECAST. WILL ISSUE AN SPS TO
HIGHLIGHT THE FREEZING DRIZZLE AND UNTREATED ROADS BECOMING
SLIPPERY FOR THE AREAS NOT CURRENTLY COVERED BY THE ADVISORY.
OTHERWISE...EXPECT THE FREEZING DRIZZLE TO DIMINISH FROM WEST TO
EAST THIS EVENING AS THE DEEPER MOISTURE FROM THE FEATURE OVER
WESTERN LAKE SUPERIOR MOVES OVER THE U.P. TONIGHT.
THE STRONG TROUGH IN THE SOUTHERN PLAINS WILL LIFT NORTHEAST
THROUGH THE LOWER GREAT LAKES REGION TONIGHT...STRENGTHENING A LOW
FROM 1007MB OVER SOUTHERN ILLINOIS TO 998MB BETWEEN LAKE
ERIE/ONTARIO AT 12Z SUNDAY. AS THAT OCCURS...THE MID LEVEL TROUGH
ASSOCIATED WITH THE SURFACE TROUGH OVER THE WESTERN LAKE WILL
DROP SOUTHEAST ACROSS UPPER MICHIGAN THROUGH SUNDAY MORNING. THE
SYNOPTIC LIQUID EQUIVALENT PRECIPITATION (TIED TO THE 850-650MB
FGEN) LOOKS TO BE IN THE 0.10-0.15 INCH RANGE FOR MOST OF THE CWA
THROUGH SUNDAY MORNING. SNOW RATIOS INITIALLY WILL LIKELY BE AROUND
10-15 TO 1 AS THERE IS STILL A PERIOD OF THE CLOUD BEING ABOVE/BELOW
THE DGZ. BUT THERE WILL LIKELY BE A TRANSITION TO A BRIEF (2-4HR)
PERIOD LATE TONIGHT INTO SUNDAY MORNING WHEN THE LOWEST 10-12KFT OF
THE ATMOSPHERE IS WITHIN THE DGZ. THIS WOULD LEAD TO A PERIOD OF
FLUFFIER SNOW AND RATIOS RISING TOWARDS OR EVEN ABOVE 20-1. DON/T
FEEL COMFORTABLE GOING MUCH ABOVE THAT DUE TO THE FORCING THAT IS
EXPECTED ABOVE THE DGZ. THUS...SYNOPTIC SNOW WOULD AMOUNT TO
1 TO 2.5-3.0 INCHES...WITH THE GREATEST OVER THE WEST HALF. BUT AS
IS NORMALLY THE CASE WITH LAKE SUPERIOR AND OUR TERRAIN
INFLUENCES...THAT ISN/T THE COMPLETE STORY ON THE SNOWFALL.
MUCH COLDER AIR WILL SURGE INTO THE AREA TONIGHT BEHIND THE
850-700MB TROUGH...WITH 850MB TEMPS FALLING FROM 19Z RAP ANALYZED
OF -5C TO -7C TO -19C EAST AND -24C WEST BY 18Z SUNDAY. THIS WILL
LEAD TO LAKE ENHANCEMENT DEVELOPING FROM WEST TO EAST TONIGHT AND
THEN TRANSITIONING TO PURE LAKE EFFECT AS THE DEEPER MOISTURE
DEPARTS ON SUNDAY. THE HELP FROM THE LAKE WILL BE FOCUSED IN THE
NORTHERLY WIND LOCATIONS OF THE WEST AND NORTH CENTRAL TONIGHT AND
THEN WINDS BACK TO THE NORTHWEST SUNDAY MORNING AND WEST-NORTHWEST
BY SUNDAY EVENING. WITH THAT COLD AIR SURGING IN...THE CLOUD LAYER
ON SUNDAY WILL TRANSITION TO BEING ABOVE THE DGZ. THUS...WOULD
EXPECT A TRANSITION OF THE SNOWFLAKES TO COLUMNS/PLATES AND LOWER
SNOW RATIOS BELOW 20-1. CONTINUED THE TREND TOWARDS THE HIGH
RESOLUTION MODELS FOR QPF AMOUNTS TONIGHT/SUNDAY IN THE
LAKE/TERRAIN ENHANCED AREAS (0.25-0.40 IN). THIS LEADS TO SNOWFALL
AMOUNTS OF 3-5 INCHES OF SNOW TONIGHT OVER THE FAVORED NORTH WIND
AREAS OVER THE WEST AND NORTH CENTRAL. THERE COULD BE SOME
LOCALIZED HIGHER AMOUNTS TOWARDS 5.5-6.0 INCHES. THE LOWERING RATIOS
ON SUNDAY WILL LEAD TO LOWER AMOUNTS OVER THE WEST...BUT COULD
STILL SEE 2-5 INCHES IN THE FAVORED NORTHWEST WINDS AREAS OVER THE
EAST. IN ADDITION TO THE SNOW...WINDS WILL QUICKLY INCREASE FROM
NORTHWEST TO SOUTHEAST TONIGHT...WITH GUSTS BETWEEN 30 TO 45 MPH
(HIGHEST NEAR LAKE SUPERIOR). THAT WILL LEAD TO BLOWING SNOW AND
COMBINED WITH THE EXPECTED SNOW...SHOULD SEE VISIBILITIES
FREQUENTLY REDUCED BELOW ONE MILE OVER THE NORTHERN HALF OF THE
CWA. THUS...THINK THE GOING ADVISORY LOOKS GOOD WITH THE FORECASTED
SNOWFALL AMOUNTS AND IMPACT WITH THE REDUCED VISIBILITIES FROM
BLOWING SNOW. AS MENTIONED ABOVE...THINK SOME HIGHER TERRAIN
LOCATIONS FLIRTING WITH 12HR WARNING SNOWFALL AMOUNTS (DUE TO THE
OVERALL AVERAGE SNOW RATIO BEING JUST BELOW OUR LAKE EFFECT WARNING
CRITERIA). BUT WITH MUCH OF THE SNOW FALLING ON A WEEKEND
OVERNIGHT AND THE EXPECTED COVERAGE FAIRLY LOCALIZED...WILL KEEP
THE ADVISORY IN PLACE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 426 PM EST SAT JAN 3 2015
TROUGHING AND WELL BELOW NORMAL TEMPERATURES DOMINATES THE WEATHER
PATTERN FOR THE FIRST FULL WEEK OF 2015 OVER NORTH AMERICA. STILL
INDICTIONS THAT A TRANSITION TO ZONAL FLOW AND ABOVE NORMAL TEMPS
DEVELOPS BY MID MONTH. ECMWF INDICATES THIS PATTERN SWITCH MAY OCCUR
AS EARLY AS NEXT WEEKEND WHILE GFS IS A BIT SLOWER. WOULD TEND TO
THINK IT MAY TAKE LONGER GIVEN THE DEGREE OF COLD AIR OVER THE
REGION AS LATE AS FRIDAY. EITHER WAY THIS UPCOMING WEEK WILL BE A
VERY COLD ONE WITH SUBZERO HIGHS ON SOME DAYS AND DANGEROUSLY LOW
WIND CHILLS. PATTERN DOES NOT HOLD MUCH OPPORTUNITY FOR WIDESPREAD
SNOW...BUT MAINLY LAKE EFFECT SNOW FOR AREAS NEAR LK SUPERIOR
FAVORED BY NORTHWEST OR WEST WINDS.
LES IN NW FLOW AREAS NEAR LAKE SUPERIOR WILL BE ONGOING SUNDAY NIGHT
IN WAKE OF THE LOW PRESSURE SYSTEM MOVING OVER THE CNTRL GREAT LAKES
ON SUNDAY. THOUGH MAIN SHORTWAVE AND SFC TROUGH WILL BE EAST OF THE
AREA...MULTIPLE SMALLER SHORTWAVES MAY PROVIDE SLIGHT ENHANCEMENT TO
LES. OVER-WATER INSTABILITY EASILY EXTREME WITH H85 TEMPS DOWN TO
-26C TO -28C AND 950MB TEMPS -22C TO -27C. LK SUPERIOR TEMPS STILL
+2C TO 3C. INVERSION HEIGHTS TOP OUT AT THE END OF THE FETCH OVER
EASTERN LK SUPERIOR 6-7KFT. DUE TO SUCH COLD AIR THE SLR/S WILL BE
WELL BLO 20:1 AS SNOWFLAKES WITHIN CONVECTIVE LAYER WILL BE PLATES
AND COLUMNS INSTEAD OF DENDRITES. RESULT IS A SNOW THAT WILL NOT
ADD UP MUCH IN TERMS OF ACCUMULATIONS...BUT WILL BE GOOD AT REDUCING
VISIBILITY. BASED ON 925MB WINDS...STEADIER LES EXPECTED SUNDAY
NIGHT AND MONDAY OVER THE KEWEENAW PENINSULA AND FOR THE SNOW BELTS
EAST OF MARQUETTE. POSSIBLE THAT ADDITIONAL ADVISORIES OR EXTENSION
OF CURRENT WINTER WEATHER ADVISORIES FOR LES WITH LOW VSBY AND GUSTY
WINDS MAY BE NEEDED INTO MONDAY...BUT WILL LET LATER SHIFTS EVALUATE
THIS ONCE WE GET THROUGH THE CURRENT ADVISORIES POSTED INTO SUNDAY.
OTHER THAN THE LES...THE COLD AND DANGEROUS WIND CHILLS WILL BE THE
MAIN STORY OVER THE CWA TO START THE WEEK. SFC RIDGE AXIS OVER THE
NORTHERN TO CENTRAL PLAINS AND LAKE INDUCED TROUGH WILL LEAD TO
MODEST PRESSURE GRADIENT OVER UPR MICHIGAN SUNDAY NIGHT INTO MONDAY
MORNING...BUT THERE IS NOT MUCH OF A LOW-LEVEL WIND MAX OVERHEAD AT
THAT TIME. EVEN SO...IT WILL NOT TAKE MUCH WIND TO PRODUCE NEAR
WARNING WIND CHILLS AS SFC TEMPS ARE EXPECTED TO BE -15F OR EVEN
-20F OVER FAR SW UPR MICHIGAN. STRONGER WINDS OF 10-15 MPH MAY BE
CLOSER TO LAKE INDUCED TROUGHING ALONG SOUTH SHORE OF LK SUPERIOR
WHERE TEMPS SHOULD BE MORE IN THE SINGLE DIGITS BLO ZERO. WIND CHILL
ADVISORIES WILL BE NEEDED FOR WEST HALF OF UPR MICHIGAN SUNDAY NIGHT
AND MONDAY...WITH POSSIBLE WARNINGS OVER FAR SW UPR MICHIGAN. COORD
WITH DLH AND GRB AND ISSUED A WIND CHILL WATCH FOR AREAS OF SW UPR
MICHIGAN /GOGEBIC...IRON...DICKINSON/ WHERE WARNING CRITERIA OF -35F
HAS BEST CHANCE OF OCCURRING.
LATER IN THE DAY ON MONDAY...A CLIPPER SHORTWAVE DIVING SE OUT OF
BRITISH COLUMBIA AND ALBERTA WILL SPREAD SNOW OVER THE NORTHERN
PLAINS AND EVENTUALLY THIS SNOW WILL MAKE IT TO THE WESTERN GREAT
LAKES ON MONDAY NIGHT. ATTM IT APPEARS THAT BULK OF THIS SYSTEM WILL
MISS UPR MICHIGAN. BY MONDAY AFTN AND MONDAY EVENING THOUGH...WINDS
BACKING WSW-SW AHEAD OF MORE NORTHERN STREAM SHORTWAVE AND COLD
FRONT DIVING SOUTHWARD OVER MANITOBA SHOULD PUSH THE LES OVER FAR
NORTHERN KEWEENAW AND OFFSHORE FM THE SNOW BELTS EAST OF MARQUETTE.
DOES NOT APPEAR WINDS BACK ENOUGH ON LK MICHIGAN TO BRING LES OFF LK
MICHIGAN INTO PLAY FOR SE CWA. LES STAYS MAINLY IN THE W FLOW AREAS
ON MONDAY NIGHT...BUT AS THE SHORTWAVE/COLD FRONT ARRIVE ON TUESDAY
WILL PUSH BACK TO NW FLOW AREAS NEAR LK SUPERIOR. SOUNDINGS SHOW
SHORTWAVE AND FRONT HAS MORE OF AN AFFECT ON THE LES AS INVERSIONS
RISE UP TO 10 KFT AS MORE COLD AIR WITH H85 TEMPS DOWN BLO -26C
SLIDES OVER THE UPPER GREAT LAKES. LIKE MONDAY...ALL OF CONVECTIVE
DEPTH IS AT TEMPS LOWER THAN DGZ...SO SMALL FLAKE SIZE AND LOW SLR/S.
NW WINDS IN MIXED LAYER NEAR 30 KTS...SO BLSN MORE OF AN ISSUE THAN
MONDAY. OVERALL THE POOR VSBY WILL CONINUE TO BE MAIN HAZARD FM THE
LES. AIR TEMPS MAY NOT BE QUITE AS COLD AS MONDAY MORNING BUT COLD
FRONT AND PRESSURE GRADIENT LOOKS MORE ROBUST. LIKELY LOOKING AT
ANOTHER ROUND OF WIND CHILL ADVISORIES FOR WEST HALF OF CWA LATE
TUESDAY NIGHT INTO WEDNESDAY MORNING. PROBABLY SHOULD STAY AWAY FM
ANY WARNING CRITERIA THOUGH.
COLD FRONT MOVES ON THROUGH WEDNESDAY AND 1045-1050MB HIGH PRESSURE
RIDGE OVER NORTHERN PLAINS PUSHES TO SOUTHERN PLAINS AND OHIO
VALLEY. IN RESPONSE...BLYR WINDS BACK MORE WNW-W BY WEDNESDAY
EVENING SO THE LES WILL IN TURN SHIFT AROUND AND NOT STAY PUT IN ANY
ONE PLACE TOO LONG. BEST CHANCE FOR MODERATE ACCUMS AND PERSISTENT
LOW VSBY WILL BE AT THE END OF THE FETCH IN THE SNOW BELTS TO EAST
OF MARQUETTE. ANOTHER COLD FRONT WILL DROP ACROSS UPPER LAKES ON
THURSDAY. YET ANOTHER SURGE OF H85 TEMPS BLO -25C WILL DESCEND ON
THE AREA. AHEAD OF THE COLD FRONT FOR THURSDAY...WEST WINDS MAY BE
STIFF LATE WEDNESDAY NIGHT INTO THURSDAY MORNING. THE STRONGER WINDS
ALONG WITH TEMPS LESS THAN 10 BLO WILL PROBABLY RESULT IN MORE WIND
CHILL ADVISORIES FOR MOST OF THE WEST HALF ON THURSDAY MORNING.
PROBABLY ARE GETTING THE THEME BY NOW. THIS WEEK LOOKS QUITE BRUTAL
IN TERMS OF THE PROLONGED DURATION OF BITTER COLD AND WIND CHILL
ISSUES. THIS WILL MAKE THE THAW EXPECTED FOR MID JANUARY FEEL ALL
THE MORE BETTER.
NW FLOW LES TO CLOSE THE WEEK AND INTO NEXT SATURDAY. THE NW WINDS
WILL RESULT IN MORE LAKE MODERATION SO TEMPS WILL BE PROBABLY BE
WARM ENOUGH TO LIMIT THE NEED OF ANY MORE WIND CHILL HEADLINES ON
FRIDAY MORNING OR SATURDAY MORNING. COULD SEE SWATH OF LGT SNOW
SWEEP OVER THE REGION NEXT WEEKEND AS THE WARM AIR BEGINS TO PUSH
OVER THE REGION ATOP OF SLOWLY RETREATING COLD AIR NEAR SFC.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1149 PM EST SAT JAN 3 2015
WITH GUSTY N TO NW WINDS/BLSN AND SNOW SHOWERS...EXPECT LIFR
CONDITIONS TO PREVAIL OVERNIGHT AT KIWD/KCMX. CONDITIONS AT KIWD
WILL IMPROVE TO IFR LATE THIS MORNING AND TO MVFR LATE IN THE AFTN
AS WINDS BACK SLOWLY AND PUSH MAJORITY OF LAKE EFFECT SNOW TO JUST N
OF THE TERMINAL. AT KCMX...INCREASINGLY COLDER AIR THRU THE DAY WILL
RESULT IN SNOWFLAKES BECOMING SMALLER AND FINER AND MUCH MORE
EFFECTIVE AT REDUCING VIS. COMBINED WITH GUSTY WINDS/BLSN...KCMX
WILL LIKELY REMAIN LIFR THRU THE MORNING WITH FURTHER REDUCTION TO
VLIFR LIKELY IN THE AFTN AND THRU TONIGHT AS WINDS BACK TO A MORE
FAVORABLE WNW DIRECTION FOR PERSISTENT/HEAVIER SNOW SHOWERS. AT
KSAW...IFR CONDITIONS WILL LIKELY FALL TO LIFR OVERNIGHT AS AREA OF
SNOW MOVES ACROSS THE AREA AND IS ENHANCED BY INCREASING UPSLOPE
WIND OFF THE LAKE. EXPECT IMPROVEMENT TO IFR MID TO LATE MORNING AND
THEN MVFR IN THE AFTN AS WINDS BACK...RESULTING IN DIMINISHED
UPSLOPE FLOW OFF THE LAKE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 335 PM EST SAT JAN 3 2015
THE BUSY MARINE WEATHER WE HAVE HAD RECENTLY WILL CONTINUE WITH
GALES AND HEAVY FREEZING SPRAY RETURNING AND HOISTED GALE WARNINGS
AND HEAVY FREEZING SPRAY WARNINGS FOR LATE TONIGHT INTO SUNDAY. A
COUPLE MORE GALE EVENTS ARE POSSIBLE ON LAKE SUPERIOR TUESDAY NIGHT
AND WEDNESDAY MORNING AND AGAIN FOR THURSDAY NIGHT WITH NORTHWEST
GALES EXPECTED THEN. FREEZING SPRAY WILL ALSO BE A PROBLEM THROUGH
MOST OF THIS FORECAST PERIOD.
WINDS SHIFT TO THE NORTH LATE TONIGHT AS THE NORTHERN PLAINS
TROUGH MERGES WITH ANOTHER LOW PRESSURE SYSTEM LIFTING NORTH OVER
THE CENTRAL GREAT LAKES. NORTH GALES TO 35-40 KTS ARE EXPECTED
SUNDAY ESPECIALLY OVER THE EASTERN HALF OF LK SUPERIOR. HEAVY
FREEZING SPRAY WILL DEVELOP TONIGHT AS ARCTIC AIR POURS OVER
LK SUPERIOR. GALES SHOULD DIMINISH BY LATE SUNDAY NIGHT...BUT NW-W
WINDS TO 30 KTS AND HEAVY FREEZING SPRAY WILL LINGER THROUGH MONDAY.
W-SW WINDS TO 25 KTS ON TUESDAY AS A CLIPPER SYSTEM CROSSES UPPER
GREAT LAKES. BEHIND THE CLIPPER...PLAN ON ANOTHER ROUND OF NW GALES
AND HEAVY FREEZING SPRAY THROUGH WEDNESDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 7 PM EST /6 PM CST/ SUNDAY FOR
MIZ001>003-009-084.
WINTER WEATHER ADVISORY FROM 4 AM TO 7 PM EST SUNDAY FOR MIZ006-
007-085.
LAKESHORE FLOOD ADVISORY UNTIL 1 PM EST SUNDAY FOR MIZ001>003.
WIND CHILL WATCH FROM SUNDAY EVENING THROUGH MONDAY MORNING FOR
MIZ009>011.
LAKESHORE FLOOD ADVISORY FROM 7 AM TO 7 PM EST SUNDAY FOR
MIZ005>007.
WINTER WEATHER ADVISORY UNTIL 7 PM EST SUNDAY FOR MIZ004-005.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 1 AM EST FRIDAY
FOR LSZ251-267.
GALE WARNING FROM 4 AM SUNDAY TO 7 AM EST MONDAY FOR LSZ249>251-
267.
HEAVY FREEZING SPRAY WARNING UNTIL 1 AM EST FRIDAY FOR LSZ249-
250-266.
GALE WARNING UNTIL 7 AM EST MONDAY FOR LSZ266.
HEAVY FREEZING SPRAY WARNING UNTIL 1 AM EST /MIDNIGHT CST/
FRIDAY FOR LSZ162-240>248-263>265.
GALE WARNING UNTIL 7 AM EST /6 AM CST/ MONDAY FOR LSZ240>248-
263>265.
GALE WARNING UNTIL 5 AM EST /4 AM CST/ SUNDAY FOR LSZ162.
LAKE MICHIGAN...
GALE WARNING FROM 7 AM TO 7 PM EST SUNDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...SRF
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
338 AM CST Sun Jan 4 2015
.SHORT TERM: (Through Late This Afternoon)
Issued at 338 AM CST Sun Jan 4 2015
System which has affected our region on Friday will continue to move
off to the north and east today into the Great Lakes. However...
a secondary shortwave currently over far south-central KS per 0730
UTC water vapor imagery. May be enough forcing for ascent associated
with this wave for some light snow showers in addition to the
more widespread flurries expected this morning. Did expand sch PoPs to
account for the possibility of measurable precipitation though snow
accumulations...if any...would be a dusting at best due to warm ground
conditions. Main change will be the much colder conditions behind
arctic front which will move through the area this morning. Highs will
range from the teens in northeast Missouri to mid 30s over portions of
southeast Missouri and south-central Illinois...though temps will drop
through the midday hour before steadying out this afternoon.
Gosselin
.LONG TERM: (Tonight through Saturday)
Issued at 338 AM CST Sun Jan 4 2015
(Tonight)
A cold/dry night is expected tonight as sfc anticyclone slides
southeastward toward the area. Winds will stay above 5 kts it looks
like and keep temperatures from bottoming out...though still appears
to be 10-15 degrees below normal with lows in the single digits/teens.
(Monday - Monday Night)
Still monitoring Alberta clipper for the Monday/Monday night period.
Latest model guidance continues to trend a bit faster and further to the
southwest with the track of the sfc low and associated snow axis. For
our CWFA...still do not see too much impact even with a southwestward
shift as main snow axis should stay across eastern IA/N IL. However...
did boost PoPs back up into the sch/chc category late Monday/Monday night
to account for the SW shift in the model guidance.
As for temperatures...used non-diurnal temperatures as after temps reach
their minimums in the upper teens/twenties...temps should rise several
degrees overnight due to southwesterly low-level flow within "warm"
sector of clipper.
(Tuesday - Saturday)
A predominantly dry...but very cold period still is in store for next
week. A strong arctic cold front will pass through the region on Tuesday
night with what will be by far and away the coldest air of the winter
of 2014-2015. Also could not rule out some light snow being squeezed out
Tuesday night as models depict some weak mid/upper level lift beneath
right-entrance region of 140-kt jet streak. Did not introduce PoPs at this
time as confidence in any measurable snowfall is low. This arctic airmass
in some ways looks to be as strong as the arctic blast of January 2014. A
1055+ hPa sfc high will slide into the middle of the country on Wednesday
with 850-hPa temperatures plummeting below -20C. Surface temperatures...even
with a total lack of snow cover over our CWFA...will be 20-30+ degrees
below normal Tuesday night through Thursday morning. Strong pressure
gradient/NW sfc winds will combine with the very cold ambient air
temperatures to produce dangerous wind chill values for this same period.
Minimum wind chill values will likely dip below -20F for portions of
northeast Missouri and west-central Illinois and will eventually warrant at
least an advisory in due time.
Temperatures will slowly moderate Thursday through Saturday but will stay
below normal.
As for chances of snow...sch/chc PoPs exist on Friday night and Saturday
as return flow/WAA ensues at low levels coincident with a shortwave
transversing the region. Medium range guidance has been highly inconsistent
however...so confidence in the chances at snow for this timeframe are
below average.
Gosselin
&&
.AVIATION: (For the 06z TAFs through 06z Sunday Night)
Issued at 1127 PM CST Sat Jan 3 2015
Surface low pressure beginning to move east northeast across
southern IL in response to upper system lifting northeast. Upper
system no longer closed and is weakening as it moves northeast.
the southern extent of the predipitation appears to be dissipating
per latest radar loops. HRRR had this trend, but it is too sparse
with the current drizzle/snow over the NW quarter of MO. Will
carry some light snow at COU and UIN for a couple of hours. Strong
nothwest wind will kick in and begin to scour out the fog.
Ceilings gradualy lift going VFR after 00z.
Specifics for KSTL: Drizzle and fog will likely persist until the
stronger northwest wind kicks in. Looks like the precipitation
will lift north and dissipate so will leave any snow/flurries
out of the forecast. Gust northwest wind and gradually liftig
ceilings will be the storm for Sunday.
JPK
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 30 12 25 23 / 20 0 5 10
Quincy 22 5 19 19 / 20 0 20 30
Columbia 20 8 24 23 / 20 0 5 5
Jefferson City 22 9 26 24 / 10 0 5 5
Salem 35 13 25 22 / 20 0 0 10
Farmington 33 14 27 25 / 10 0 0 5
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1134 PM CST Sat Jan 3 2015
.UPDATE:
Issued at 938 PM CST Sat Jan 3 2015
Eastern Missouri and western Illinois are stuck in a weak cyclonic
lobe of surface pressure at this time, with the old frontal system
well to the east in the OH/TN Valley region and the first Arctic
cold front pushing into northwest MO. This weak flow has resulted
in fog and quite a bit of drizzle, some of which is measurable.
Meanwhile to the west, the coverage of precipitation is increasing
across western MO in response to large scale forcing/ascent
associated with the shortwave across eastern KS into northeast OK.
The changeover to snow in western MO is taking its time with temps
still in the mid-upper 30s. Present indications are the
aforementioned shortwave will rotate east northeast tonight in
association with the lifting and weakening upper trof. This will
result in precipitation spreading from western MO across central
and northeast MO into western IL through the late evening and
overnight, with St. Louis on the tail end. I`m not real excited
about seeing much measurable snowfall given the slow changeover,
marginal temps, and in general a weakening system. Best odds of
accumulations will be in north central/northeast MO where around
an inch is possible. The Arctic front itself will continue to
surge southeast for the remainder of the night into early Sunday
morning with gusty northwest winds ushering some mighty chilly air
into the area and scouring out the soupy IFR conditions. Cloudy
skies, falling temps, and flurries likely through the day on Sunday.
Glass
&&
.SHORT TERM: (Through Sunday)
Issued at 339 AM CST Sat Jan 3 2015
Forecast on track with upper level low/shortwave moving northeast
across the region this evening. Precipitation associated with this
feature should start as rain and then transition to snow before
ending. Best chance of an inch of accumulation will be across the
far northern CWA. Otherwise, some mood snow showers or flurries
will be the rule as colder air pours into the region overnight
into Sunday morning. Sunday will be breezy and much colder with
temperatures continuing to slowly fall throughout the day.
.LONG TERM: (Monday through Next Saturday)
Issued at 230 PM CST Sat Jan 3 2015
Temperature will moderate some on Monday as a clipper system
tracks north of the area. Have kept the forecast dry based on the
consensus track of the system to our north.
Pattern really amplifies behind this clipper with a very strong
arctic high pressure system moving into the mid section of the
country for midweek. This will be the coldest air we have seen this
winter season. Expect temperatures to be at 20 to 30 degrees below
normal Tuesday night through Thursday. As previous forecaster
stated, below zero temperatures are likely for a large portion of
the area Thursday morning as the center of the anticyclone will be
parked over head. The latest MEX guidance has below zero
temperatures at STL both Wednesday and Thursday morning - WITH NO
SNOW COVER. Have trended the forecast colder based on the latest
model data and expect wind chill values will warrent advisories to
be issued in the future.
Airmass really struggles to moderate before the next storm system
moves toward the area late next week and weekend. This could set the
stage for a more widespread winter weather event across the CWA
Friday night/Saturday morning. For now will keep chance POPs for
snow as the ECWMF does not depict as deep/strong of a
shortwave/surface reflection at this time.
CVKING
&&
.AVIATION: (For the 06z TAFs through 06z Sunday Night)
Issued at 1127 PM CST Sat Jan 3 2015
Surface low pressure beginning to move east northeast across
southern IL in response to upper system lifting northeast. Upper
system no longer closed and is weakening as it moves northeast.
the southern extent of the predipitation appears to be dissipating
per latest radar loops. HRRR had this trend, but it is too sparse
with the current drizzle/snow over the NW quarter of MO. Will
carry some light snow at COU and UIN for a couple of hours. Strong
nothwest wind will kick in and begin to scour out the fog.
Ceilings gradualy lift going VFR after 00z.
Specifics for KSTL: Drizzle and fog will likely persist until the
stronger northwest wind kicks in. Looks like the precipitation
will lift north and dissipate so will leave any snow/flurries
out of the forecast. Gust northwest wind and gradually liftig
ceilings will be the storm for Sunday.
JPK
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 25 29 12 24 / 60 10 0 0
Quincy 17 20 5 18 / 80 10 0 0
Columbia 18 20 8 23 / 60 10 0 0
Jefferson City 19 23 8 25 / 60 10 0 0
Salem 31 34 13 23 / 20 20 0 0
Farmington 29 32 13 26 / 30 10 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1120 PM CST Sat Jan 3 2015
.UPDATE...
Issued at 916 PM CST SAT JAN 3 2015
Have issued a quick update to lower snow amounts south of I70 and
raise snow amounts across northern Missouri.
Water vapor with the 1.5 PVU pressure overlayed clearly shows the
strong shortwave over Kansas causing our weather mess locally.
Projecting this PV anomaly in time shows it lifting east-northward
right over the forecast area. This typically not a great scenario to
get deformation snowfall through the heart of the forecast area.
Rather, the drop in static stability associated with the PV anomaly
has lead to very "showery" type precip. This was likely enhanced by
the elevated instability from 00Z KTOP sounding showing ~160 J/kg for
a parcel lifted from above 700 mb. Earlier in the evening there was a
rapid transition from rain to snow in south central KS that to a
quick several inches of snow. This was associated with an area of
strong Fn convergence 750 to 700 mb layer along/north the developing
TROWAL as the system appeared to be peaking in intensity. The NAM
showed this area moving ENE but weakening as it did so and not really
being an issue. However, as the system matures, what looks like the
main deformation band is setting up over northern
Missouri/northeastern Kansas and corresponds to a newly strengthening
area of Fn convergence in the 700 to 650 mb layer along and just
north of the newly emerging TROWAL in the 300-305K layer. This shift
northward is supported by the latest HRRR and RUC as well as the
latest run of our local WRF-ARW.
The higher reflectivity returns showing up on radar in the last 30
minutes or so should continue to lift northward and feed into the
main deformation area to the north. Also, with the southeastern half
of the forecast area still above freezing, what has been snowing has
had an opportunity to accumulate as it melts on contact with the
warmer ground, cutting into accumulations further south.
So overnight snow amounts look like 1-2 inches in the northwestern half
of the forecast area with less than 1 inch amounts over the
southeastern half. Parts of the northern KC metro may still see 1-2
inches but lower amounts are expected further south.
&&
.SHORT TERM...(This Evening through Sunday Night)
Issued at 426 PM CST SAT JAN 3 2015
Tonight:
The second phase of the approaching winter system will quickly make
its presence felt over our CWA. The latest satellite and radar data
reveal the rapid development of the deformation zone precipitation
shield across south central and central KS. Satellite trends appear
to support the latest operational NAM, GFS and ECMWF which depict a
more southern track (vs yesterday`s solutions) of the main
precipitation. The HRRR and RUC also confirm this. So, with only
minor adjustments needed have shifted the axis of heavier snowfall
a bit further south.
Model output via Bufkit and the operational model snow algorithms
all point to a general 1-2 inch swath with isolated amounts to 3
inches possible from east central KS through west central MO. Snow
amounts will be limited by 1) initially falling as rain and 2)
melting at onset due to above freezing temperatures. An expected
quick transition to snow due to strong dynamic forcing within the
deformation cloud shield and the eventual surge of strong cold air
advection should mitigate this melting. Also of note is the
convective looking nature of the growing deformation cloud shield.
Close inspection of Bufkit data and model soundings suggest CSI may
be possible for a brief period early this evening with elevated CAPE
values approaching 100 J/kg. Evening shift will need to keep an eye
on this for possible thunder-snow and rapid increase in snow rates.
Strong cold air advection will rush from the Central Plains this
evening. Upstream obs show single digit temperatures and wind gust
of 35-40 mph. Thus blowing snow tied to the baroclinc zone snow
which will form across southeast NE this evening will be added to
the northern and western CWA. Have also allowed light snow/flurries
to linger well after midnight as ice crystals will be produced down
into the boundary layer as temperatures fall to -15C within the
saturated cloud layer between 2500-5000ft agl.
Due to the combo of 25-35 mph winds and single digit temperatures
have added a wind chill advisory for the northwest tip of MO.
Sunday and Sunday Night:
Brutally cold. That`s all you need to know. A 1041 mb surface high
will sit over KS and western MO during this period. A stiff
northwest wind will diminish from west to east in the morning and
clouds will clear so we`ll get some relief from the cold. However,
the weight of h8 temperatures of -10C to -15C will limit highs to
mainly the teens.
Some mid level warm advection clouds streaming in from NE may be the
saving grace for below zero temperatures Monday night. That plus
very light winds may only generate wind chills from -5 to -15F.
.LONG TERM...(Monday through Saturday)
Issued at 426 PM CST SAT JAN 3 2015
Looking ahead to the extended...everyone may want to keep those
heavy winter coats out a while longer. The forecast continues to
remain cold and mostly dry until late in the upcoming work week. An
upper level ridge will remain planted across the western US coast
with a very wide longwave trough over the remainder of the US. This
places the CWA in northwest flow aloft with a number of disturbances
translating through the main flow. Each of these systems will
provide a reinforcing shot of cold air into the region. With snow
remaining on the ground, airmass modification will be minimal
allowing morning lows to tumble into the low single digits with a
few negative single digits along the MO/IA border Monday morning.
While the EC and GFS 850mb temperatures are off a few degrees from
each other, they are still bringing in temperatures ranging from -17 to
-25 C over the CWA. Thus, it is likely that lows will plummet into
the negative singles Wed morning across the northern half of CWA,
and then low singles on either side of zero by Thurs morning. High
temperatures look to warm into the upper teens and into the low and
mid 20s much of the week, except Wed when it will be tough to climb
into the teens. Precip-wise, the northeast corner of the CWA may see
some light snow Mon night as one of the previously mentioned systems
glances the area. Long-range models are also indicating that the
region may see increasing chances for precip late in the week, but
given that it is towards the end of the extended a lot can, and
probably will, change over the next several days as the system
begins to evolve.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1111 PM CST SAT JAN 3 2015
Snow will continue to affect the KC terminals area until slowly
tapering off between 08Z-10Z. Conditions will be in and out of IFR
during the snowfall with gusty winds up to 25kts further restricting
visibilities. Will see a gradual improvement after the heavier precip
works its way out of the KC area around 08Z, with lingering snow
flurries until the early morning hours. Expecting MVFR ceilings
after this event with gusty winds continuing until the early
afternoon.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY until 3 AM CST Sunday FOR KSZ025-057-
103>105.
WINTER WEATHER ADVISORY until 6 AM CST Sunday FOR KSZ102.
MO...WINTER WEATHER ADVISORY until 3 AM CST Sunday FOR MOZ013>017-
020>025-028>033-037>039-043-044.
WINTER WEATHER ADVISORY until 6 AM CST Sunday FOR MOZ001>008-011-
012.
WIND CHILL ADVISORY from 3 AM to 9 AM CST Sunday FOR MOZ001-002-
011.
&&
$$
UPDATE...CDB
SHORT TERM...MJ
LONG TERM...PMM
AVIATION...Welsh
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
338 AM EST SUN JAN 4 2015
.SYNOPSIS...
COLD FRONT CROSSES TODAY. GUSTY WINDS AND SNOW SHOWERS FLURRIES IN
ITS WAKE TONIGHT INTO MONDAY MORNING. HIGH PRESSURE MONDAY EVENING.
FAST CLIPPER TUESDAY FOLLOWED BY ARCTIC BLAST WEDNESDAY/THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
LOW PRESSURE CENTER DRAGS A COLD FRONT THROUGH THE AREA TODAY AS IT
CONSOLIDATES OVER THE EASTERN GREAT LAKES. MAIN PLUME OF RAINFALL
GOOD FOR ABOUT AN INCH GIVE OR TAKE OVER A 6 HOUR PERIOD EXITS FIRST
THING THIS MORNING. SHOWERS ACCOMPANY AND IMMEDIATELY FOLLOW THE
FRONT ITSELF...STILL IN WRN OHIO EARLY THIS MORNING AND W OF THE
FCST AREA AT DAWN.
THE FRONT WILL PUSH THROUGH THE AREA LATER THIS MORNING THROUGH
EARLY THIS AFTERNOON W TO E. STRONG PRESSURE GRADIENT WITH PRESSURE
RISE OF 8 MB/6 HRS THIS AFTERNOON INTO TONIGHT SUGGEST GOOD MIXING
AND MOMENTUM TRANSPORT. USED RUC MOMENTUM ALGORITHM TO ARRIVE AT
GUSTS TO 30 KTS HILLTOPS DURING THE FRONTAL PASSAGE TODAY AND
CONTINUING SEVERAL HOURS AFTER...WITH UP TO 40 KTS OVER THE HIGHER
TERRAIN...THESE GUSTS MAY PERSIST THERE MUCH OF THE NT TONIGHT.
THESE VALUES FALL SHY OF ADV CRITERIA THOUGH.
AFTER A DRY SLOT LATER TODAY...UPSLOPE SHOW SHOWERS SHOULD INCREASE
OVER THE HIGHER WINDWARD TERRAIN TONIGHT AS H85 TEMPERATURES CRASH
TO -10C OR LOWER OVERNIGHT...SUPPORTIVE OF ICE CRYSTALS. AM A
LITTLE UNDER WWD WITH UP TO AN INCH OVER THE HIGHER WINDWARD
TERRAIN. MOISTURE DEPTH INCREASES AS MAIN UPPER LEVEL S/W TROUGH
AXIS CROSSES THIS EVENING...ALSO GIVING RISE TO CRYSTAL GROWTH AND
SCATTERED RAIN SHOWERS CHANGING TO SNOW SHOWERS EVEN OUT ACROSS THE
LOWLANDS EARLY TONIGHT. OTHERWISE STRATOCU PERSISTS BENEATH
LOWERING SUBSIDENCE INVERSION THROUGH THE BALANCE OF THE NEAR TERM
PERIOD.
BLENDED IN MAINLY NAM BASED HOURLY TEMPERATURES IN THE STRONG COLD
ADVECTION...HIGHS OCCUR EARLY TODAY.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
PERIOD WILL BEGIN WITH SMALL CHANCES OF SNOW IN THE MOUNTAINS.
HOWEVER...ANY PRECIPITATION SHOULD END QUICKLY AS HIGH PRESSURE
MOVES EAST ACROSS THE REGION. THIS HIGH SHOULD RESULT IN DRY
WEATHER REGION-WIDE BY LATE MONDAY MORNING....AND CONTINUE INTO
MONDAY NIGHT.
A FAST MOVING LOW PRESSURE SYSTEM WILL THEN BRING PRECIPITATION
CHANCES BACK TO THE REGION LATE MONDAY NIGHT. MODELS DIFFER ON THE
TRACK OF THE LOW AND ASSOCIATED PRECIPITATION...WITH THE NAM
LIMITING ANY MEASURABLE TO OUR EXTREME NORTHERN AREAS. THE
GFS/ECMWF AND HPC 6-HR PRECIPITATION FORECAST SUGGESTS THE EDGE OF
THE MEASURABLE PRECIPITATION WILL BE FARTHER SOUTH. HAVE TWEAKED
THE POPS AND QPF GRIDS TOWARDS THE SOLUTION OF THE GFS/ECMWF/HPC.
AS A RESULT...HAVE LIKELY OR HIGHER POPS ACROSS OUR NORTHERN TWO
TIER OF COUNTIES FROM LATE MONDAY NIGHT INTO TUESDAY AFTERNOON.
BEHIND THE LOW...COLDER AIR AND WESTERLY WINDS WILL COMBINE WITH
SUFFICIENT MOISTURE TO BRING A GOOD CHANCE OF UPSLOPE SNOW TUESDAY
EVENING INTO THE OVERNIGHT HOURS.
THE UPSLOPE SNOW SHOULD DECREASE BY LATE TUESDAY NIGHT. HOWEVER...
ANOTHER UPPER LEVEL SYSTEM WILL SWEEP SOUTHEAST ACROSS THE AREA ON
WEDNESDAY...WITH SNOW SHOWERS CHANCES CONTINUING.
MET/MAV GUIDANCE IS QUITE CLOSE FOR MONDAY THROUGH TUESDAY...AND WAS
CLOSE TO WHAT WE HAVE IN OUR GRIDS...SO DID NOT MAKE ANY MAJOR
CHANGES. MEX GUIDANCE IS ALSO CLOSE TO OUR GRIDS FOR TUESDAY NIGHT
AND WEDNESDAY...SO ONLY SOME MINOR TWEAKS WERE MADE.
CURRENT THINKING IS THAT SNOWFALL AMOUNTS UP TO 2 INCHES ARE
POSSIBLE ACROSS OUR NORTHERN COUNTIES FROM LATE MONDAY NIGHT THROUGH
TUESDAY...WITH A FEW INCHES POSSIBLE IN THE NORTHERN MOUNTAINS LATE
TUESDAY THROUGH TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
FRONT END OF THE EXTENDED DEALS WITH THE TAIL END OF THE CLIPPER
TYPE LOW PRESSURE SYSTEM WITH DECREASING CHANCES OF SNOW OVER THE
NORTHERN TIER OF THE CWA THROUGH TUESDAY NIGHT. IN THE WAKE OF THE
SYSTEM...UPPER LEVEL LOW DEEPENS OVER THE GREAT LAKES WHILE SURFACE
HIGH PRESSURE BUILDS OVER THE MIDWEST AS IT MOVES IN FROM THE LEE OF
THE CANADIAN ROCKIES. OF INTEREST IS THE ECMWF THAT HAS THE HIGH
REACHING 1060MB OVER THE BLACK HILLS AREA IN SOUTH DAKOTA.
THAT HIGH PRESSURE SHOULD BE GOOD TO GO THROUGH THE END OF THE
WEEK...ALTHOUGH MAY NEED TO WATCH FOR ANOTHER GREAT LAKES CLIPPER
TYPE SYSTEM FRIDAY. LOW CONFIDENCE WITH THIS AT THIS POINT.
NOT TOO MANY CHANGES TO THE TEMPERATURES WEDNESDAY THROUGH THURSDAY
WITH HIGHS STRUGGLING TO HIT 20F AND LOWS BELOW 0F POSSIBLE
WEDNESDAY NIGHT. SKIES SHOULD CLEAR...BUT WIND STAYS UP...SO
RADIATIONAL COOLING NOT EXPECTED AT THIS TIME. THIS WILL KEEP VALLEY
TEMPERATURES FROM DROPPING FURTHER.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
LARGE LOW PRESSURE COMPLEX OVER THE OHIO VALLEY AND GREAT LAKES
CONSOLIDATES OVER THE EASTERN GREAT LAKES SUNDAY MORNING AND THEN
SPINS NEWD INTO THE ST LAWRENCE RIVER VALLEY SUN NT. THIS WHIPS A
COLD FRONT THROUGH THE AREA SUNDAY MORNING 14Z HTS TO 18-19Z IN THE
MOUNTAINS EKN BKW.
RAIN AHEAD OF THE COLD FRONT OVERNIGHT WILL BRING CIGS AND VSBYS TO
MVFR WITH IFR VSBY IN HEAVIER RAIN. THIS RAIN MOVES OUT OF THE AREA
FROM SW TO NE BY 15Z SUN...BUT ONE MORE THIN LINE OF SHOWERS WILL
ACCOMPANY THE FRONT PASSAGE.
DRIER AIR ON GUSTY WINDS WILL IMPROVE VSBYS TO VFR MOST OF THE
BALANCE OF THE PERIOD BUT MVFR STRATOCU WILL PERSIST. SNOW SHOWERS
MAY BRING VSBYS BACK DOWN TO MVFR IN THE NORTHERN MOUNTAINS LATE SUN
NT.
GUSTY S SFC FLOW AHEAD OF THE FRONT OVERNIGHT WILL BECOME STRONG AND
GUSTY FROM THE SW BEHIND THE FRONT SUNDAY...WITH GUSTS AROUND 25 KTS
SUNDAY AFTERNOON. THESE STRONG WINDS WILL PERSIST INTO SUN NT.
STRONG SW FLOW ALOFT WILL INCREASE TO 60 KTS AHEAD OF THE FRONT
TOWARD DAWN SUN NEAR LLJ MAX TIME...AND THEN BECOME MODERATE TO
STRONG W BEHIND THE FRONT SUN AND SUN NT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z MONDAY...
FORECAST CONFIDENCE: LOW TO MEDIUM.
ALTERNATE SCENARIO: TIMING OF LOWER CIG/VIS IN PRECIPITATION COULD
VARY. WIND GUSTS WILL VARY ESPECIALLY OVERNIGHT.
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 SUN 01/04/15
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 L L M M H M L M H M H H
HTS CONSISTENCY M M M M L M L M H H H H
BKW CONSISTENCY H M M M L H M M H H H H
EKN CONSISTENCY H M M L L M M H H H H M
PKB CONSISTENCY M M M M M L L M L M H H
CKB CONSISTENCY L L M M L L L L L L H M
AFTER 06Z MONDAY...
IFR IN SNOW SHOWERS POSSIBLE LATE SUNDAY NIGHT IN THE MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/TRM
NEAR TERM...TRM
SHORT TERM...JSH
LONG TERM...26
AVIATION...TRM
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1221 AM EST SUN JAN 4 2015
.SYNOPSIS...
LOW PRESSURE OVER NORTHWEST OHIO WILL CONTINUE NORTHEAST AND
CROSS THE EASTERN GREAT LAKES TONIGHT. A COLD FRONT TRAILING THE
LOW WILL SWEEP ACROSS THE AREA LATE TONIGHT AND EARLY SUNDAY.
ARCTIC HIGH PRESSURE WILL BUILD EAST ON MONDAY. A CLIPPER LOW
PRESSURE SYSTEM WILL CROSS THE AREA ON TUESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
TRICKY FORECAST TONIGHT WITH TEMPS THE MAIN CHALLENGE. READINGS
HAVE CLIMBED IN THE MID 50S ALONG THE I-71 CORRIDOR BUT REMAIN IN
THE MID 30S OVER NW OHIO. TEMPS PROBABLY WILL REMAIN ABOUT WHERE
THEY ARE THE REMAINDER OF THE NIGHT AND HAVE TRIED TO WORD THE NEW
FORECAST ACCORDINGLY. THE LASTEST HRRR AND RUC CONTINUE TO SHOW
ANOTHER WAVE OF PRECIP MOVING ACROSS THE AREA OVERNIGHT. MOST OF
THIS SHOULD BE OVER THE EASTERN TWO THIRDS OF THE AREA.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
SUNDAY WILL BEGIN WITH A CHANCE OF RAIN WITH RAIN CHANGING TO SNOW
FROM WEST TO EAST AS COLDER AIR MOVES IN BEHIND THE FRONT. 12Z
850MB TEMPS STILL POSITIVE ACROSS OHIO BUT BY 18Z -4C LINE GETS TO
KCLE WITH -6C AT KTOL. BEST WRAP AROUND MOISTURE GETS INTO THE
AREA DURING THE AFTERNOON POST DRY SLOT. WILL HAVE CHANCE POPS FOR
MOST OF THE AREA THROUGH THE MORNING AND THEN BOOST TO LIKELY WEST
HALF FOR THE AFTERNOON...TRANSITIONING THE LIKELY POPS TO
NORTHEAST OHIO AND NWRN PA FOR THE EVENING AS DRIER AIR MOVES IN
FROM THE WEST. AT THIS TIME NOT EXPECTING A LOT OF SNOW AND WILL
HAVE LESS THAN AN INCH. OVERNIGHT SUNDAY NIGHT WILL CONTINUE WITH
LIKELY POPS ACROSS THE SNOWBELT WITH ABOUT 3 INCHES OR SO FOR
ACCUMS. MONDAY ARCTIC HIGH PRESSURE BUILDS IN FROM THE NORTHWEST.
THE AIRMASS DRYS OUT SIGNIFICANTLY. WILL HAVE DRY BUT UNPLEASANTLY
COLD CONDITIONS FOR MOST THE AREA. EXCEPTION BEING THE SNOWBELT.
WITH THE FORECAST KERI SOUNDING SHOWING MODERATE INSTABILITY WITH
THE LAKE AM EXPECTING LAKE EFFECT TO CONTINUE THROUGH THE DAY.
INVERSION IS NOT VERY HIGH AT AROUND 5KFT BUT SNOW GROWTH TEMPS
ARE FAVORABLY POSITIONED WITHIN THE UPDRAFTS WITH VERY LITTLE SHEAR
OR TURNING OF THE WIND. FOR NOW GIVEN THE DRY AIR WILL LIMIT
ACCUMS TO AN INCH OR TWO BUT WILL NEED TO CONTINUE TO WATCH.
OTHERWISE MONDAY MORNING TEMPS/WINDS MAY REQUIRE A WIND CHILL
ADVISORY AS APPARENT TEMPS GET TO AROUND 7 BELOW ZERO NWRN OHIO.
NEXT BIG ISSUE WILL BE THE CLIPPER THAT TRACKS ACROSS THE AREA
MONDAY NIGHT AND TUESDAY. SEE A GOOD 3 TO 5 INCH ACCUM IF IT
REMAINS ON TRACK. AGAIN TIME WILL TELL BUT FOR NOW DID BRING IN 2
TO 4 INCHES WEST HALF FOR LATE MONDAY NIGHT WITH SIMILAR AMOUNTS
EAST BEGINNING LATE MONDAY NIGHT THROUGH TUESDAY.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
COLD AIR WILL BE SURGING SOUTHWARD IN THE WAKE OF A MORNING COLD
FRONT ON WEDNESDAY. MAY HAVE LITTLE OR NO RISE IN TEMPERATURES IF
THIS TIMING HOLDS. WE ARE TALKING SINGLE DIGIT/LOW TEENS
HIGHS...LOWS ON EITHER SIDE OF ZERO...AND WIND CHILLS BELOW ZERO.
THIS FRONT WILL ALSO BRING WITH IT A LITTLE LIGHT SNOW FOR MOST
WEDNESDAY AND LAKE EFFECT FOR THE SNOWBELT GOING INTO AND THROUGH
THURSDAY. HIGH PRESSURE FROM THE NORTHERN PLAINS WILL HAVE SHIFTED
SOUTHEAST TO THE LOWER OHIO AND TN VALLEYS BY THURSDAY NIGHT
BRINGING THE FLOW AROUND TO THE SOUTHWEST. WITH THE COLD AIR
ENCOMPASSING EVERYWHERE EAST OF THE ROCKIES THE WARM AIR
ADVECTION/AIRMASS MODIFICATION LATER IN THE WEEK WILL ONLY BRING
TEMPERATURES SLOWLY UP THROUGH THE UPPER TEENS THURSDAY AND TO THE
LOWER 20S FOR FRIDAY AND SATURDAY.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
SURFACE LOW PRESSURE IS NEAR TOL WITH A WARM FRONT EXTENDING EAST
INTO LAKE ERIE. RADAR MOSAIC SHOWS MOST OF THE STEADY RAIN HAS
LIFTED WAY FROM THE REGION WITH ONLY SCATTERED SHOWERS REMAINING.
CIGS AND AND VSBY RANGE FROM IFR NEAR TOL AND FDY TO MAINLY MVFR
ELSEWHERE AT THE TAF SITES TO THE SOUTH AND EAST.
FRONTAL BOUNDARY WILL DRIFT EAST UNTIL ABOUT 12Z TO BE FROM NEAR
CLE TO MFD. AFTER 12Z THE BOUNDARY WILL QUICKLY SWEEP EAST ACROSS
THE REMAINING TAF SITES ONCE THE LAST WAVE ON THE FRONT LIFTS TO
THE NORTH. COLD AIR WILL SWEEP INTO THE REGION AND IMPROVE CIGS
AND VSBY FOR A WHILE. BY MID TO LATE AFTERNOON SOME LIGHT SNOW IS
EXPECTED WHICH WILL REDUCE VSBY TO MVFR WITH CIGS NEAR 1500 FT.
AFTER FRONTAL PASSAGE SOUTHWEST WINDS WILL INCREASE TO 15-20KT
WITH GUSTS TO NEAR 30 KT.
SOME IMPROVEMENT IS EXPECTED SUNDAY EVENING AWAY FROM THE LAKE
WITH MAINLY MVFR CONDITIONS. NEAR LAKE ERIE ESPECIALLY NEAR ERI
LAKE EFFECT SNOW BANDS WILL LIKELY DEVELOP SUNDAY EVENING AND
REDUCE CONDITIONS TO IFR.
.OUTLOOK...NON-VFR CONTINUES SUNDAY NIGHT. VFR MAY RETURN BRIEFLY
ON MONDAY THEN NON VFR AGAIN TUESDAY AND WEDNESDAY. BY THURSDAY
NON-VFR SHOULD BE LIMITED TO FAR NE OH/NW PA.
&&
.MARINE...
GALE WARNING STILL HOLDS FOR SUNDAY...ALTHOUGH IT MAY NEED TO BE
EXTENDED INTO SUNDAY NIGHT FOR THE EASTERN HALF OR SO. SSW WINDS
TONIGHT WILL SHIFT TO THE SW WITH THE PASSAGE OF A COLD FRONT EARLY
SUNDAY MORNING...WITH THE LOW CENTER TRACKING FROM NW OHIO INTO
QUEBEC. WIND SPEEDS WILL RAMP UP QUICKLY TO GALE FORCE WITH AND
AFTER THE FRONTS PASSAGE. WATER LEVELS WILL DROP ON THE WESTERN
BASIN TO NEAR THE CRITICAL MARK AND WILL CONTINUE TO EVALUATE THE
NEED FOR A LOW WATER ADVISORY ON SUNDAY. COLD AIR CONTINUES TO PUSH
ACROSS THE LAKE SUNDAY NIGHT AND THE GRADIENT MAY REMAIN TIGHT
ENOUGH TO KEEP LOW END WESTERLY GALES ACROSS THE EAST HALF. HIGH
PRESSURE BUILDS OVER THE OHIO VALLEY MONDAY ALLOWING WINDS TO BACK
TO THE SOUTHWEST AND BEGIN TO SLOWLY DIMINISH. SMALL CRAFT
ADVISORIES WILL LIKELY GO INTO TUESDAY MORNING FOLLOWING THE GALES.
NEXT INCREASE IN WINDS...AROUND 30 KNOTS WILL COME TUESDAY NIGHT AND
WEDNESDAY AS AN ARCTIC COLD FRONT BRINGS A SURGE OF VERY COLD AIR
OVER THE GREAT LAKES. THOSE WINDS WILL SLOWLY DIMINISH THURSDAY
AS...ONCE AGAIN HIGH PRESSURE BUILDS OVER THE OHIO VALLEY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...GALE WARNING FROM 1 PM THIS AFTERNOON TO 1 AM EST MONDAY FOR
LEZ061-143>149-163>169.
&&
$$
SYNOPSIS...TK
NEAR TERM...KUBINA
SHORT TERM...TK
LONG TERM...OUDEMAN
AVIATION...LAPLANTE
MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
342 AM CST SUN JAN 4 2015
.DISCUSSION...
AN UPPER LEVEL SHORTWAVE TROUGH EVIDENT ACROSS THE SOUTHERN PLAINS
THIS MORNING WILL MOVE EAST TODAY. THIS WILL HELP TO PUSH A COLD
FRONT ACROSS THE MID SOUTH. ALTHOUGH THIS SYSTEM WILL NOT HAVE A
LOT OF DEEP MOISTURE TO WORK WITH...THERE MAY BE ENOUGH TO SUPPORT
A FEW SPRINKLES EARLY THEN SOME FLURRIES AS TEMPERATURES FALL
THROUGH THE DAY BEHIND THE FRONT ACROSS NORTHERN SECTIONS. HIGH
PRESSURE WILL EVENTUALLY BUILD INTO THE REGION LATER TONIGHT WITH
CLEARING SKIES AND DRY WEATHER THAT WILL PERSIST THROUGH THE FIRST
PART OF THE WEEK. TEMPERATURES WILL REMAIN COLD ON MONDAY BUT
SHOULD QUICKLY WARM BACK TO NEAR NORMAL ON TUESDAY.
A STRONG ARCTIC COLD FRONT WILL MOVE ACROSS THE MID SOUTH TUESDAY
NIGHT WITH SOME OF THE COLDEST AIR THIS WINTER SEASON INVADING THE
MID SOUTH ON WEDNESDAY. A 1050+ MB SURFACE HIGH PRESSURE WILL
BUILD INTO THE REGION WITH HIGH TEMPERATURES REMAINING IN THE
MIDDLE 20S NORTH TO MIDDLE 30S SOUTH BY WEDNESDAY AFTERNOON. THE
BRUNT OF THE COLD AIR WILL BE FELT WEDNESDAY NIGHT INTO THURSDAY.
LOW TEMPERATURES SHOULD DROP INTO THE SINGLE DIGITS NORTH TO
MIDDLE TEENS SOUTH BY SUNRISE THURSDAY MORNING. IN
ADDITION...WINDS MAY REMAIN BRISK ON WEDNESDAY EVENING WHICH MAY
RESULT IN WIND CHILL VALUES NEAR OR SLIGHTLY BELOW ZERO. A WIND
CHILL ADVISORY MAY BECOME NECESSARY DURING THIS MID WEEK PERIOD.
HIGHS AGAIN ON THURSDAY WILL REMAIN VERY COLD WITH LOWER 20S NORTH
TO NEAR 30 DEGREES SOUTH BUT WITH CONTINUED DRY CONDITIONS. DRY
WEATHER WILL CONTINUE THROUGH THE END OF THE WEEK WITH ONLY A SLOW
MODERATION IN TEMPERATURES.
A SHORTWAVE DISTURBANCE IN THE SOUTHERN STREAM SHOULD MOVE ACROSS
THE MID SOUTH BY NEXT WEEKEND. THIS SYSTEM MAY BRING THE NEXT
CHANCES FOR PRECIPITATION TO THE AREA DURING THE END OF THE
EXTENDED FORECAST PERIOD. TEMPERATURES SHOULD REMAIN BELOW NORMAL
DURING THIS PERIOD AND MAY SUPPORT SOME WINTRY TYPE PRECIPITATION.
AT THIS TIME...ANY PRECIPITATION THAT OCCURS APPEARS TO REMAIN
LIGHT AND THERE IS STILL PLENTY OF TIME TO DETERMINE SPECIFIC
PRECIPITATION TYPES AND TEMPERATURE PROFILES AS WE GET CLOSER TO
NEXT WEEKEND.
JLH
&&
.AVIATION...
06Z TAFS
MVFR/VFR WAS NOTED ON 05Z METARS OVER AR...AS LOW STRATUS DECK HAD
BROKEN UP IN PLACES. NAM SOUNDINGS AND 00Z HRRR MODEL SHOW IFR
CONTINUING...AND WILL NEED TO WATCH SHORT TERM TRENDS FOR JBR AND
MEM. OTHERWISE...HELD STATUS QUO GIVEN THE MODEL CONSISTENCY WITH
EARLIER RUNS. VFR LIKELY TO PREVAIL AREAWIDE BY EARLY SUNDAY
EVENING...WITH ARCTIC HIGH PRESSURE PREVAILING.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
325 AM EST SUN JAN 4 2015
.SHORT TERM (TODAY AND TONIGHT)...
PRECIP OVER THE AREA AT THE MOMENT IS OCCURRING WELL AHEAD OF THE
SURFACE COLD FRONT...WHICH IS STILL LOCATED IN WEST TN. THE HRRR
SEEMS TO HAVE A GOOD HANDLE ON THE CURRENT PRECIP...SO IT WILL BE
FOLLOWED FOR SHORT TERM TIMING. IT TAKES MOST OF THE MODERATE PRECIP
EAST OF OUR AREA BY NOON...SO WILL QUICKLY DROP POPS BACK INTO THE
CHANCE RANGE AFTER THAT TIME EVERYWHERE...WITH JUST A SLIGHT CHANCE
NORTH AND IN THE MTNS THROUGH THE MID-LATE AFTERNOON. SO FAR THIS
MORNING...WE HAVE NOT OBSERVED WINDS IN THE MOUNTAINS NEAR ADVISORY
CRITERIA...SO THE CURRENT WIND ADVISROY WILL BE CANCELLED.
THE RAP AND NAM SHOW THE SURFACE FRONT MOVING THROUGH OUR AREA IN
THE 16-21Z TIME FRAME. OUR HIGH TEMPS TODAY WILL BE IN THE MORNING
AS TEMPS FALL WITH COLD ADVECTION BEHIND THE FRONT THROUGH THE
AFTERNOON. PLENTY OF LOW LEVEL MOISTURE LINGERS BEHIND THE
FRONT...WHICH SHOULD KEEP CLOUDS IN PLACE. IN THE EVENING...LAPSE
RATES STEEPEN WITH THE 850-700 MB TROUGH PASSAGE AND WINDS TURN W-
NW. SW VA AND EAST TN MTNS COULD SEE SOME LIGHT SNOW SHOWERS...BUT
WITH MOISTURE BEING SHALLOW BELOW THE -10C LEVEL...ANY SNOW IS NOT
EXPECTED TO ACCUMULATE. WILL HAVE JUST A SLIGHT CHANCE OF SNOW
SHOWERS. THE TREND OF DECREASING MOISTURE DEPTH CONTINUES
OVERNIGHT...ENDING ANY REMAINING CHANCE OF PRECIP BY 06Z.
.LONG TERM (MONDAY THROUGH SATURDAY)...
QUIET WEATHER IN THE LONG TERM...LOW AND ASSOCIATED
PRECIP WILL HAVE MOVED OUT OF THE AREA AND SHOULD TAKE SOME OF THESE
CLOUDS WITH IT AS WELL. BIGGEST CONCERN IN THE LONG TERM WILL BE
TEMPS, ESPECIALLY BEHIND A FRONT THAT SHOULD MOVE THROUGH TUESDAY
NIGHT INTO WEDNESDAY MORNING. BEHIND THE FRONT COLD AIR WILL BE
FORCED IN ALONG WITH WINDS OUT OF THE NORTH/NORTHWEST. WINDS SHOULD
START TO CALM DOWN BEFORE THE LOWEST TEMPS ARE REACHED OVERNIGHT
WEDNESDAY. MOST OF THE AREA IS EXPECTED TO REACH SINGLE DIGIT TEMPS,
AND EVEN WITH RELATIVELY LIGHT WINDS, WIND CHILL VALUES COULD STILL
GET BELOW 0 DEGREES. TAKING A QUICK GLANCE BACK AT HISTORIC OBS
REVEALS THAT THERE HAVE BEEN NUMEROUS WINTERS OVER THE PAST COUPLE
OF DECADES WHERE TEMPS HAVE NOT GOTTEN THIS COLD, IF THE FORECAST
VERIFYS. SHOULD STAY BELOW FREEZING UNTIL FRIDAY WHEN MOST OF THE
AREA SHOULD REACH INTO THE MID 30`S FOR A HIGH TEMP. AT THE END OF
THE FORECAST SOME MODELS WANT TO BRING IN A TROUGH AND SOME PRECIP,
BUT OTHERS WANT TO KEEP US HIGH AND DRY, SO AT THIS POINT CONFIDENCE
IS LOW AT THE VERY END OF THE FORECAST AS FAR AS PRECIP CHANCES GO.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 60 30 41 28 / 50 10 0 0
KNOXVILLE MCGHEE TYSON AIRPORT, TN 57 27 38 26 / 70 10 0 0
OAK RIDGE, TN 57 26 39 28 / 50 10 0 0
TRI CITIES AIRPORT, TN 57 24 35 22 / 100 20 0 0
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS/ABM
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1148 PM CST SAT JAN 3 2015
.UPDATE...
UPDATED FOR 06Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 707 PM CST SAT JAN 3 2015/
UPDATE...
UPDATED TO LOWER THUNDERSTORM THREAT AND TO ADJUST TEMPERATURES.
ALSO UPDATED THE HWO FOR REMOVAL OF SLIGHT RISK THREAT.
DISCUSSION...
MAIN BAND OF HIGHER INSTABILITY ASSOCIATED WITH THE PRE-FRONTAL
TROUGH HAS CLEARED THE CWA...WITH THE COLD FRONT JUST NOW EXITING
THE MEMPHIS METRO. BELIEVE THE THREAT OF THUNDER...AND SEVERE
THREAT OVER THE SOUTHEAST COUNTIES...HAS SIGNIFICANTLY DWINDLED
..SO HAVE ADJUSTED THE FORECAST FOR ONLY SLIGHT CHANCE FOR
THUNDER...AND REMOVED THE SLIGHT RISK FOR SEVERE FROM THE HWO.
ALSO MADE ADJUSTMENTS TO TEMPERATURES AS BOTH THE FRONT WILL TAKE
ITS TIME EXITING...AND ABUNDANT CLOUD COVER WILL LINGER WELL INTO
SUNDAY MORNING.
JAB
PREV DISCUSSION... /ISSUED 547 PM CST SAT JAN 3 2015/
UPDATE...
UPDATED FOR 00Z AVIATION DISCUSSION BELOW.
PREV DISCUSSION... /ISSUED 301 PM CST SAT JAN 3 2015/
DISCUSSION...
SKIES REMAIN CLOUDY ACROSS MUCH OF THE FORECAST AREA THIS
AFTERNOON WITH TEMPERATURES RANGING FROM THE UPPER 40S TO MID 60S.
A LARGE AREA OF RAIN CONTINUES TO MOVE ACROSS THE EASTERN HALF OF
THE FORECAST AREA. THIS AREA OF RAIN HAS LITTLE THUNDER ASSOCIATED
WITH AN RAINFALL IS NOT PARTICULARLY HEAVY. WITH THAT IN MIND WILL
CANCEL FLASH FLOOD WATCH AT 330 PM CST. WILL ALSO REMOVE MENTION
OF SEVERE WEATHER FROM THE HWO.
THE COLD FRONT IS PUSHING INTO FAR WESTERN SECTIONS OF THE
FORECAST AREA THIS AFTERNOON. THE COLD FRONT WILL MOVE THROUGH THE
FORECAST AREA TONIGHT WITH RAIN ENDING FROM WEST TO EAST BY SUNDAY
MORNING. TEMPERATURES WILL START TO TURN COLDER BEHIND THE FRONT
LATE TONIGHT WITH LOWS SUNDAY MORNING IN THE UPPER 30S TO MID 40S.
HIGH PRESSURE BUILDS INTO THE CENTRAL PLAINS ON SUNDAY. AS IT DOES
WINDS WILL SHIFT TO THE NORTHWEST AND START TO BRING INTO COLDER
AIR INTO THE REGION. HIGH TEMPERATURES ON SUNDAY WILL NOT BE MUCH
WARMER THAN THEY WILL BE IN THE MORNING. CLOUDS SHOULD CLEAR
SUNDAY NIGHT AND COMBINED WITH LIGHT WINDS WILL ALLOW TEMPERATURES
TO DROP IN THE LOW TO MID 20S OVER THE FORECAST AREA BY MONDAY
MORNING. MONDAY WILL BE SUNNY BUT CHILLY WITH HIGHS IN THE LOWER
30S TO LOWER 40S.
BY MONDAY NIGHT...THE SURFACE HIGH SHOULD BE EAST OF THE REGION
ALLOWING WINDS TO SHIFT TO THE SOUTH AND BRING SOMEWHAT MILDER AIR
INTO THE FORECAST AREA. TEMPERATURES WILL NOT BE AS COLD MONDAY
NIGHT WITH LOWS TUESDAY MORNING IN THE MID 20S TO AROUND 30
DEGREES. TUESDAY WILL BE DRY AND A LITTLE MILDER WITH HIGHS IN THE
40S TO AROUND 50 DEGREES.
ANOTHER COLD FRONT WILL MOVE THROUGH THE REGION TUESDAY AFTERNOON
AND EVENING. THIS FRONT WILL HAVE LITTLE MOISTURE TO WORK WITH
AHEAD OF IT SO NO PRECIPITATION IS EXPECTED. THE AIR BEHIND THIS
FRONT WILL BE MUCH COLDER THAN THE AIR WE WILL SEE MOVING INTO THE
REGION ON SUNDAY. LOWS WEDNESDAY MORNING WILL BE MAINLY IN THE
20S.
AS BRISK NORTH WINDS BLOW ACROSS THE REGION ON WEDNESDAY AFTERNOON
TEMPERATURES WILL NOT WARM UP TOO MUCH WITH HIGHS IN THE MID 20S
TO MID 30S. WEDNESDAY NIGHT AND THURSDAY MORNING WILL BE VERY COLD
AS LOWS THURSDAY MORNING IN THE TEENS. IN ADDITIONAL WINDS OF
AROUND 10 MPH WILL PUSH WIND CHILL READINGS TO THE SINGLE DIGITS
TO NEAR ZERO. THURSDAY WILL NOT REMAIN DRY AND CHILLY WITH HIGHS
IN THE 20S.
BY THURSDAY NIGHT...WINDS SHOULD RETURN TO THE SOUTH SO
TEMPERATURES WILL START TO MODERATE SOME. BY FRIDAY MOST LOCATIONS
WILL SEE HIGHS IN THE 30S. BY FRIDAY NIGHT...A WARM FRONT WILL
START TO MOVE INTO THE REGION. AS THIS DOES MOISTURE WILL START TO
INCREASE AND THERE WILL BE A SMALL CHANCE OF PRECIPITATION. AT
THIS POINT...IT LOOKS AS THOUGH PRECIPITATION WILL START OUT AS
SOME SLEET OR FREEZING RAIN BUT THERE IS MUCH UNCERTAINTY AT THIS
TIME. BY NEXT SATURDAY...AS TEMPERATURES WARM TO ABOVE FREEZING
ANY FROZEN PRECIPITATION WILL CHANGE OVER TO RAIN.
ARS
&&
.AVIATION...
06Z TAFS
MVFR/VFR WAS NOTED ON 05Z METARS OVER AR...AS LOW STRATUS DECK HAD
BROKEN UP IN PLACES. NAM SOUNDINGS AND 00Z HRRR MODEL SHOW IFR
CONTINUING...AND WILL NEED TO WATCH SHORT TERM TRENDS FOR JBR AND
MEM. OTHERWISE...HELD STATUS QUO GIVEN THE MODEL CONSISTENCY WITH
EARLIER RUNS. VFR LIKELY TO PREVAIL AREAWIDE BY EARLY SUNDAY
EVENING...WITH ARCTIC HIGH PRESSURE PREVAILING.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1140 PM CST SAT JAN 3 2015
.AVIATION...
LATEST COLD FRONT HAS JUST PASSED EACH TAF SITE. NORTHERLY SURFACE
WINDS WILL GUST MODESTLY FOR THE NEXT 2-3 HOURS WHILE A BAND OF
MOSTLY MVFR CLOUDS WILL FOLLOW THOUGH SHOULD TEND TO FRACTURE AS
IT APPROACHES KLBB SO LESS CLEAR IF A CEILING WILL RESULT AT KLBB.
DRIER AIR BY 2AM TO 3AM SUNDAY SHOULD LEAD TO FURTHER EROSION AND
EVENTUAL CLEARING TOWARDS MORNING WITH VFR CONDITIONS AS WELL AS
DROPPING WIND SPEEDS. WIND DIRECTION SHOULD GRADUALLY RETURN TO
SOUTH OR SOUTHEAST BY LATE IN THE DAY THOUGH SPEEDS VERY LIGHT SO
DID NOT INDICATE THIS CHANGE YET. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 548 PM CST SAT JAN 3 2015/
AVIATION...
DOWNSLOPE WESTERLY COMPONENT EARLY THIS EVENING SHOULD KEEP
SURFACE SATURATION FROM OCCURRING...THOUGH CANNOT COMPLETELY RULE
THIS OUT BY 03Z-06Z JUST BEFORE THE NEXT FRONT ARRIVES. THE LATEST
HIGH RESOLUTION HRRR RUN SHOWS SATURATION DEVELOPING NOT FAR FROM
EITHER KPVW OR KLBB BY THIS TIME SO WE WILL BE KEEPING A CLOSE EYE
ON TRENDS. OTHERWISE...EXPECTING MUCH IMPROVED CONDITIONS THOUGH
ARRIVAL OF A COLD FRONT AROUND 05Z-06Z FOR EACH SITE. SOME
POSSIBILITY OF A LOW CLOUD LAYER POST-FRONT AS INDICATED WITH THE
SCT020 LAYER. ONCE AGAIN...WE WILL CLOSELY FOLLOW TRENDS THOUGH
CURRENT INDICATIONS SUPPORT MUCH DRIER AND COLDER AIR BEHIND THIS
FRONT WHICH SHOULD FAVOR VFR CONDITIONS. RMCQUEEN
PREV DISCUSSION... /ISSUED 255 PM CST SAT JAN 3 2015/
SHORT TERM...
THE STORM SYSTEM THAT BROUGHT THE VARIETY OF WINTRY PRECIPITATION TO
THE REGION THE PAST COUPLE OF DAYS WAS FINALLY ACCELERATING AWAY TO
THE NORTHEAST. HOWEVER...IT DID NOT GO QUIETLY...WITH AN AREA OF
WRAP AROUND SNOW IMPACTING MUCH OF THE NORTHERN HALF OF THE CWA
THROUGH EARLY AFTERNOON...BRINGING ADDITIONAL SNOWFALL RANGING FROM
A LIGHT DUSTING TO A QUICK 2 INCHES. THE BIGGEST SNOWFALL WINNERS
FOR THE EVENT WERE ACROSS OUR FAR NORTHWEST ZONES WITH FRIONA
REPORTING A HALF FOOT AND RHEA COMING IN WITH 9 INCHES. THE SNOW HAS
SINCE DIMINISHED AND MOST SPOTS WERE NOW SEEING SOME SUN AND BRISK
WESTERLY WINDS WHICH HAVE ALLOWED TEMPERATURES TO CLIMB TO AND ABOVE
THE FREEZING MARK. THIS WAS HELPING TO THAW THINGS OUT...THOUGH WAS
ALSO CREATING THE RISK OF FALLING ICE WHERE SIGNIFICANT FREEZING
RAIN OCCURRED YESTERDAY.
ALTHOUGH WE HAVE SEEN A RELATIVE WARM-UP THIS AFTERNOON...IT IS
STILL TOO EARLY TO BREAK OUT THE SHORTS AND FLIP FLOPS. INSTEAD...WE
WILL SEE ANOTHER COLD FRONT PLUNGE THROUGH THE SOUTH PLAINS TONIGHT
BEHIND THE DEPARTING UPPER LOW AND UNDER DEVELOPING DRY NORTHWEST
FLOW ALOFT. THE FRONT OF INTEREST IS CURRENTLY MOVING THROUGH
EASTERN COLORADO AND NORTHWEST KANSAS AND IS PROGGED TO MOVE THROUGH
THE SOUTH PLAINS AROUND AND SHORTLY AFTER MIDNIGHT. BREEZY NORTHERLY
WINDS AND COLD ADVECTION BEHIND THE FRONT WILL RESULT IN A CHILLY
NIGHT. TEMPERATURES ACROSS THE DEEPEST SNOWPACK OF OUR NORTHWEST
ZONES MAY DIP INTO THE SINGLE DIGITS...WHILE TEENS WILL BE COMMON
OVER MUCH OF THE REMAINDER OF THE FA. THE COLD TEMPERATURES AND
BREEZY WINDS WILL DROP WIND CHILLS INTO THE SINGLE DIGITS AT MANY
LOCATIONS EARLY SUNDAY...WITH A FEW BELOW ZERO READING ACROSS THE
FAR NORTHWEST. THAT SAID...IT DOES APPEAR WIND CHILL VALUES WILL
COME UP JUST SHY OF ADVISORY LEVELS...THOUGH IT WILL BE COLD
NONETHELESS. A SHORT-LIVED DECK OF STRATUS CLOUDS COULD EVEN FOLLOW
THE FRONT...BUT SHOULD QUICKLY SHIFT TO THE SOUTHWEST AND WEST ON
SUNDAY. AREAS OF FREEZING FOG COULD ALSO DEVELOP NEAR THE TX/NM LINE
EARLY SUNDAY...THOUGH IT APPEARS THE BETTER SHOT WILL BE IN EASTERN
NM AND WE HAVE LEFT THE MENTION OUT OF THE FORECAST ATTM. EVEN
SO...THE SURFACE RIDGE BUILDING IN BEHIND THE COLD FRONT WILL KEEP
TEMPERATURES CHILLY TOMORROW...WITH HIGHS ONLY EXPECTED TO RISE INTO
THE UPPER 20S AND LOWER 30S.
LONG TERM...
BROAD CYCLONIC FLOW TO REMAIN ACROSS MUCH OF THE CONUS NEXT
WEEK...ALTHOUGH WILL SEE RIDGING DEVELOP OVER THE WEST COAST AND
EASTERN PACIFIC THEN SLOWLY EDGE EWD WITH TIME. THIS PATTERN WILL
KEEP BELOW NORMAL TEMPS IN PLACE THROUGH THE WEEK WITH MODEL PROGS
SHOWING SHARPLY COLDER TEMPS WEDNESDAY AS THE NEXT PIECE OF COLD
AIR DROPS SWD INTO THE EASTERN TWO-THIRDS OF THE CONUS WITH
ANOTHER WEAKER BUT STILL COLD PIECE MOVING SWD LATE IN THE WEEK.
OTHER ITEM TO WATCH IS A SHORT WAVE TROUGH PROGGED TO MOVE EWD
ACROSS THE DESERT SW AND/OR NRN MEXICO POSSIBLY SPREADING SOME
LIGHT PRECIP ACROSS THE FCST AREA TOWARD SATURDAY. STILL A LOT OF
UNCERTAINTY WITH THIS TROUGH. WITH MODELS CONTINUING TO FAVOR THE
SERN ZONES WILL KEEP A SLIGHT MENTION THERE.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 8 28 16 42 24 / 0 0 0 0 0
TULIA 12 28 15 41 22 / 0 0 0 0 0
PLAINVIEW 13 29 17 41 24 / 0 0 0 0 0
LEVELLAND 15 32 18 43 27 / 0 0 0 0 0
LUBBOCK 15 30 19 42 26 / 0 0 0 0 0
DENVER CITY 18 31 18 41 26 / 0 0 0 0 0
BROWNFIELD 17 30 18 41 26 / 0 0 0 0 0
CHILDRESS 15 29 17 38 23 / 0 0 0 0 0
SPUR 19 29 17 40 27 / 0 0 0 0 0
ASPERMONT 21 31 18 45 27 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/05
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
309 AM CST SUN JAN 4 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 309 AM CST SUN JAN 4 2015
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A NORTHERN STREAM TROUGH OVER SOUTH CENTRAL CANADA INTO NORTH
DAKOTA...A SOUTHERN STREAM TROUGH FROM THE CENTRAL PLAINS INTO
ILLINOIS..AND RIDGES ON BOTH COASTS OF THE U.S.. ALSO OF NOTE WERE A
POTENT SHORTWAVE IN MO AND IL WITH A WEAKER SHORTWAVE MOVING THROUGH
THE FORECAST AREA. THIS LATTER SHORTWAVE IN CONJUNCTION WITH MID
LEVEL FRONTOGENESIS HAS SUPPORTED A BAND OF SNOW ACROSS MUCH OF THE
FORECAST AREA. SEE THE LATEST MKEPNSARX FOR UPDATED SNOWFALL
AMOUNTS THROUGH THE MORNING. ANY PRECIPITATION WITH THE POTENT
SHORTWAVE HAS STAYED SOUTH OF THE FORECAST AREA. HOWEVER...WE ARE
FEELING ITS EFFECTS IN THE WIND DEPARTMENT...AS THAT POTENT
SHORTWAVE HAS HELPED TO DEEPEN A SURFACE LOW NOW OVER LOWER MI.
NORTHWEST WINDS HAVE BEEN GUSTING IN THE 20-40 MPH RANGE...HIGHEST
WEST OF U.S. HIGHWAY 52. THESE WINDS ARE ADVECTING ARCTIC AIR INTO
THE REGION FROM THE NORTHERN STREAM UPPER TROUGH IN SOUTH CENTRAL
CANADA. 925MB TEMPS PER RAP ANALYSIS HAVE FALLEN TO -5C SOUTHEAST
TO -15C NORTHWEST ACROSS THE FORECAST AREA...WITH SURFACE
TEMPERATURES FROM THE MID TEENS SOUTHEAST TO UPPER SINGLE DIGITS
NORTHWEST. MEANWHILE...MUCH COLDER -20 TO -24C 925MB AIR WAS
LURKING ACROSS THE EASTERN DAKOTAS AND WESTERN MN...AND AROUND
-30C UNDER THE UPPER TROUGH. READINGS ARE WELL BELOW ZERO UNDER
THIS COLDER AIR.
THE MID LEVEL FRONTOGENETICAL BAND OF SNOW CURRENTLY OVER THE
FORECAST AREA SHOULD MOVE OFF TO THE EAST QUICKLY THIS MORNING...IN
RESPONSE TO THE SHORTWAVE OVER THE AREA MARCHING EAST. MOST MODEL
GUIDANCE SUGGESTS BY 15Z THE SNOW SHOULD HAVE PUSHED OFF TO THE
EAST...WITH MAYBE SOME LINGERING FLURRIES OVER WI UNTIL 18Z. THE
REST OF THE SHORT TERM PERIOD IS DRY AS SUBSIDENCE AND DRY ARCTIC
AIR MOVE IN.
ATTENTION THEN TURNS TO TEMPERATURES/WIND CHILLS AS ARCTIC AIR POURS
INTO THE REGION...IN RESPONSE TO THE UPPER TROUGH OVER SOUTH CENTRAL
CANADA CROSSING THE FORECAST AREA. 925MB TEMPS FALL TO -20 TO -24C
BY 00Z AND -23 TO -27C BY 12Z MONDAY. THIS ADVECTION OF ARCTIC AIR
COMBINED WITH A 15 TO 25 MPH SUSTAINED WIND SPEED TODAY CAUSES WIND
CHILLS TO EVENTUALLY FALL INTO ADVISORY CRITERIA / LESS THAN 20
BELOW ZERO / EVERYWHERE BY SUNSET. FURTHER COOLING TAKES PLACE
TONIGHT TO PUT TAYLOR AND CLARK INTO WARNING CRITERIA / 35 BELOW
ZERO. PORTIONS OF SOUTHEAST MN COULD GET CLOSE TO WARNING AS
WELL.
REGARDING HAZARDS. CONSIDERED WAITING UNTIL 15Z...THE EXPIRATION
TIME OF THE WINTER WEATHER ADVISORY FOR OUR WESTERN 10 COUNTIES...TO
START HOISTING THE WIND CHILL ADVISORIES. HOWEVER...GIVEN THE REST
OF THE FORECAST AREA IS SEEING WIND CHILL ADVISORY CRITERIA
TODAY...AND ALL NEIGHBORING FORECAST OFFICES ALSO HOISTING
ADVISORIES...HAVE ISSUED THE ADVISORIES NOW. HAVE ALSO UPGRADED THE
WATCH FOR TAYLOR/CLARK TO A WARNING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 309 AM CST SUN JAN 4 2015
THE ARCTIC AIR OVER THE REGION TO START MONDAY MODIFIES QUITE A BIT
THROUGH THE DAY...REFLECTED BY 925MB TEMPS CLIMBING TO -18 TO -21C
BY 00Z. THIS MODIFICATION ALLOWS OUR WIND CHILLS TO MOSTLY GET ABOVE
ADVISORY CRITERIA BY 18Z...WHICH IS THE END TIME FOR THE HAZARDS.
SOME EXTENSION PAST 18Z COULD BE REQUIRED FOR A FEW AREAS.
HOWEVER...THE IMPROVEMENT IN WIND CHILLS COMES AT THE EXPENSE OF
SNOW MOVING INTO THE REGION DURING THE AFTERNOON.
04.00Z MODEL GUIDANCE CONTINUES TO DEPICT A FAST MOVING POTENT
SHORTWAVE...CURRENTLY IN THE GULF OF ALASKA...TRACKING FROM CENTRAL
MONTANA AT 18Z MONDAY TO EASTERN IOWA BY 06Z TUESDAY. THIS IS A
DISTANCE OF 925 MILES...RESULTING IN A 77 MPH AVERAGE SPEED FOR THE
SHORTWAVE. THE COMBINATION OF DPVA FROM THE SHORTWAVE...DIVERGENCE
FROM THE LEFT EXIT REGION OF AN UPPER JET AND STRONG MID LEVEL
FRONTOGENESIS...WILL LEAD TO A BROAD SWATH OF SNOW ON THE ORDER OF
300 MILE WIDTH. CONTAINED WITHIN THAT SWATH WILL BE A SMALLER...
HEAVIER BAND ON THE ORDER OF 100 MILE WIDTH PER MODEL CONSENSUS.
LIQUID EQUIVALENT AMOUNTS COULD BE AS HIGH AS 0.5 INCH AS SUGGESTED
BY THE NAM/GFS AND SOME SREF MEMBERS. WITH A DEEP EFFECTIVE
DENDRITIC GROWTH OF 300MB...THAT COULD RESULT IN 8 TO 12 INCHES OF
SNOWFALL...MUCH OF WHICH FALLING WITHIN IN A 9 HOUR WINDOW. THE
SERIOUS PROBLEM IN FORECASTING THESE HIGH AMOUNTS IS PLACEMENT. THE
BOUNDS SEEMS TO BE THE SOUTHERN PORTION OF THE FORECAST AREA PER THE
04.00Z NAM AND ALONG I-80 PER THE 04.00Z GFS. GIVEN THIS LARGE
PLACEMENT ISSUE...CANNOT FORECAST THE HIGHER AMOUNTS YET.
HOWEVER...THE WINTER STORM WATCH IS VERY MUCH WARRANTED...THOUGH
LATER SHIFTS MAY BE ABLE TO TRIM OFF THE NORTHERN SIDE OF THE WATCH.
REGARDING PRECIPITATION CHANCES...HAVE INCREASED THEM QUITE A BIT
FOR MONDAY AFTERNOON GIVEN FASTER TIMING...ALONG WITH MORE OF A
DECREASE FOR OVERNIGHT MONDAY NIGHT.
ATTENTION THEN TURNS BACK TO THE ARCTIC COLD AS A SHORTWAVE TROUGH
CURRENTLY OVER BAFFIN ISLAND DROPS SOUTH ACROSS THE AREA TUESDAY
NIGHT AND WEDNESDAY. THIS SHOT OF ARCTIC AIR LOOKS NASTY AS 925MB
TEMPS FALL FROM -14C TO -18C AT 12Z TUESDAY...TO -18 TO -21C AT 00Z
WEDNESDAY...TO -26C TO -28C BY 12Z WEDNESDAY AND HOLDING IN THE -24
TO -28C RANGE FOR MUCH OF WEDNESDAY. TEMPERATURES SHOULD PLUMMET
WELL BELOW ZERO FOR TUESDAY NIGHT AND STAY BELOW ZERO ON WEDNESDAY.
IN FACT...MEX GUIDANCE SUGGESTS SOME LOCATIONS ON WEDNESDAY MAY NOT
CLIMB ABOVE -10. ADD INTO THIS A BRISK NORTHWEST WIND INDUCED BY
925MB WINDS IN THE 35-45 KT RANGE COMING ACROSS TUESDAY NIGHT AND
WEDNESDAY...THIS IS A PERFECT RECIPE FOR WIND CHILLS TO DROP TO NEAR
OR INTO WARNING CRITERIA EVERYWHERE. IT MAY NOT BE UNTIL SOMETIME
THURSDAY WHEN WE FINALLY GET OUT OF ADVISORY CRITERIA.
A BRIEF WARM UP IS PROGGED THURSDAY IN RESPONSE TO WARM ADVECTION
AHEAD OF ANOTHER POTENT SHORTWAVE DROPPING SOUTH INTO MN. THIS WARM
ADVECTION LOOKS TO INDUCE SOME LIGHT SNOW OVER THE NORTHEAST HALF OF
THE FORECAST AREA. HAVE RAISED PRECIPITATION CHANCES TO 30-40 AND
MAY NEED FURTHER INCREASES. IN THE WAKE OF THE SHORTWAVE...ANOTHER
ARCTIC AIRMASS DROPS IN...SIMILAR TO THE ONE FOR TONIGHT. MORE WIND
CHILL HEADLINES ARE LIKELY. FOLLOWED A MODEL CONSENSUS FOR HIGHS
FRIDAY AND LOWS THURSDAY NIGHT THROUGH FRIDAY NIGHT...BUT THESE MAY
NEED TO BE LOWERED 3-5 DEGREES.
AS WE HEAD INTO THE WEEKEND...THE HIGH LATITUDE BLOCKING PATTERN
ACROSS THE PACIFIC INTO WESTERN NORTH AMERICA FINALLY BREAKS DOWN.
THIS WILL ALLOW FOR A MODERATING TREND ACROSS THE FORECAST
AREA...GETTING TEMPERATURES BACK UP TO NEAR NORMAL BY MONDAY NEXT
WEEK. HOWEVER...IT APPEARS ACCOMPANYING THE WARM ADVECTION COULD BE
SOME LIGHT SNOW FOR LATE SATURDAY INTO SATURDAY NIGHT PER 04.00Z
ECMWF.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1136 PM CST SAT JAN 3 2015
SNOW HAS MOVED INTO KRST AND IT IS REDUCING VISIBILITIES TO A HALF
MILE. CEILINGS ARE CURRENTLY MVFR THERE...BUT WITH IFR CONDITIONS
JUST WEST THESE LOWER CEILINGS SHOULD MOVE IN SOON. THIS SNOW WILL
SNOW MOVE INTO KLSE AROUND 04.07Z. THE SNOW WILL THEN LINGER FOR
4 TO 6 HOURS. TOTAL SNOW ACCUMULATIONS WILL BE AROUND 2 INCHES. IN
ADDITION TO THE SNOW... STRONG NORTHWEST WINDS OF 15 TO 25 KNOTS
WITH GUSTS TO 35 KNOTS WILL PRODUCE SOME BLOWING SNOW ACROSS
SOUTHEAST MINNESOTA...NORTHEAST IOWA...AND WESTERN WISCONSIN. THIS
BLOWING SNOW WILL REDUCE VISIBILITIES TO 3 MILES AT KRST THROUGH
SUNDAY MORNING.
AS SUBSIDENCE INCREASES ACROSS THE AREA...EXPECT SKIES TO CLEAR
ACROSS SOUTHEAST MINNESOTA AND NORTHEAST IOWA BETWEEN 04.15Z AND
04.21Z...AND KLSE AROUND 04.21Z. AT THIS TIME...THE WIND GUSTS
SHOULD SUBSIDE. HOWEVER SUSTAINED WINDS WILL REMAIN AROUND 15
KNOTS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WIND CHILL ADVISORY FROM 9 AM THIS MORNING TO NOON CST MONDAY
FOR WIZ032>034.
WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO NOON CST MONDAY
FOR WIZ041>044-053.
WINTER STORM WATCH FROM MONDAY EVENING THROUGH LATE MONDAY NIGHT
FOR WIZ053>055-061.
WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO NOON CST MONDAY
FOR WIZ054-055-061.
WIND CHILL WARNING FROM 9 PM THIS EVENING TO NOON CST MONDAY FOR
WIZ017-029.
WIND CHILL ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS
EVENING FOR WIZ017-029.
MN...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY
NIGHT FOR MNZ086-087-094>096.
WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR MNZ086-
087-094-095.
WIND CHILL ADVISORY FROM 9 AM THIS MORNING TO NOON CST MONDAY
FOR MNZ079-086>088-094-095.
WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO NOON CST MONDAY
FOR MNZ096.
IA...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY
NIGHT FOR IAZ008>011-018-019-029-030.
WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR
IAZ008>010-018-019-029.
WIND CHILL ADVISORY FROM 9 AM THIS MORNING TO NOON CST MONDAY
FOR IAZ008-009-018-019.
WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO NOON CST MONDAY
FOR IAZ010-011-029.
WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO NOON CST MONDAY
FOR IAZ030.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS ALBANY NY
933 AM EST SUN JAN 4 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE FROM THE EASTERN GREAT LAKES
REGION TO SOUTHERN QUEBEC TODAY. A STRONG COLD FRONT WILL MOVE
ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND LATE THIS AFTERNOON
INTO TONIGHT WITH RAIN SHOWERS TRANSITIONING TO SNOW SHOWERS.
BLUSTERY AND COLD CONDITIONS WILL OPEN THE WORK WEEK WITH LAKE
EFFECT SNOW SHOWERS MAINLY NORTH AND WEST OF THE GREATER CAPITAL
REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 933 AM EST...WITH THE BEST ISENTROPIC LIFT NOW WELL NORTH OF
OUR AREA...AND A SECONDARY AREA OF LOW PRESSURE OVER EASTERN NEW
ENGLAND MOVING AWAY FROM THE REGION...STEADY PRECIPITATION IS
TAPERING OFF ACROSS MUCH OF THE AREA...WITH JUST SOME LINGERING
RAIN OVER WESTERN NEW ENGLAND. TEMPERATURES HAVE RISEN ABOVE
FREEZING FOR MOST...ALTHOUGH THERE STILL ARE POCKETS OF SUB-
FREEZING TEMPS...MAINLY IN THE CT RIVER VALLEY OF SE VERMONT.
ALTHOUGH THE NEXT FEW HOURS WILL MAINLY BE RAIN FREE...THERE MAY
BE SOME LINGERING AREAS OF RAIN/DRIZZLE...ESP FOR WESTERN NEW
ENGLAND...SO HAVE ISSUED AN SPS TO ACCOUNT FOR THE LINGERING
POCKETS OF FREEZING RAIN. OTHERWISE...HAVE LET THE ONGOING WSW
EXPIRE ACROSS THE AREA...AS THE THREAT FOR ADDITIONAL ICING
APPEARS TO BE OVER. ALL AREAS LOOK TO SEE TEMPS ABOVE FREEZING BY
NOON.
THE MAIN STORM SYSTEM IS LOCATED OVER SRN ONTARIO. THE H850 WINDS
ARE SHIFTING TO THE SW FOR THE LATE MORNING INTO THE AFTERNOON.
THE SFC WARM FRONT WILL TRY TO BREAK THROUGH MOST OF THE REGION.
EXPECT PLENTY OF CLOUDS TO BE AROUND AND H850 TEMPS TO RISE TO +7C
TO +10C. OUR MAX TEMPS REFLECT THE METMOS VALUES WITH M40S TO L50S
ACROSS THE REGION. THE COLDEST TEMPS WILL BE IN SE VERMONT WHERE
THE COLD AIR WILL BE TOUGHEST TO DISLODGE.
IT APPEARS A PREFRONTAL TROUGH WILL MOVE ACROSS THE REGION IN THE
LATE AFTERNOON AND THE COLD FRONT WILL APPROACH FOR THE EARLY
EVENING. THE LLJ AT H850 INCREASES TO 45-60 KTS AHEAD OF THE COLD
FRONT...AS THE SFC WAVE MOVES INTO SRN QUEBEC. THE CYCLONE DOES
DEEPEN TO CLOSE TO 990 HPA BY 00Z/MON. THE 6-HR PRESSURE FALLS ARE
EXPECTED TO BE OVER SE QUEBEC AND NRN NEW ENGLAND. THE H925 WINDS
AHEAD AND JUST BEHIND THE FRONT CONTINUE TO BE STRONG AT 30-40
KTS...BUT MIXING DOWN 40 KTS IN THE EARLY EVENING MAY BE
DIFFICULT. WE WILL CONTINUE TO HAVE SOME GUSTS TO 30 TO 40 WITH A
BURST OF SHOWERS WITH THE FRONT. EXPECT THE SHOWERS TO TRANSITION
TO SNOW SHOWERS ACROSS THE WRN DACKS IN THE EARLY EVENING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
...LAKE EFFECT SNOW ADVISORY ISSUED FROM 7 PM SUNDAY TO 7 AM
MONDAY FOR NORTHERN HERKIMER AND HAMILTON COUNTIES...
...LAKE EFFECT SNOW ADVISORY ISSUED FROM 4 AM MONDAY TO 7 PM MONDAY
FOR SOUTHERN HERKIMER...FULTON AND MONTGOMERY COUNTIES.
THE ADVISORIES ARE FOR SNOW AND BLOWING SNOW WITH GUSTY WINDS OF
35 TO 45 MPH.
OUR CONFIDENCE WAS NOT GREAT ENOUGH TO ISSUE A WIND ADVISORY FOR
PARTS OF THE REGION SUNDAY NIGHT...THOUGH A 3RD PERIOD ADVISORY
MAY BE NEEDED FOR MONDAY...AS BETTER MOMENTUM TRANSFER IS
EXPECTED...BUT FOR NOW WIDESPREAD 46-57 MPH WIND GUSTS ARE NOT
ANTICIPATED FOR SUNDAY NIGHT INTO MONDAY. THIS WILL CONTINUE TO BE
MONITORED.
TONIGHT...COLD FRONT MOVES ACROSS THE REGION WITH STRONG LOW LEVEL
COLD ADVECTION EXPECTED. WESTERLY UPSLOPE SNOW SHOWERS WILL
INITIALLY IMPACT THE WRN DACKS AND SRN GREENS MTNS WITH MORE SCT
RAIN AND SNOW SHOWER ACTIVITY AWAY FROM THESE AREAS.
THE LATEST HIRES WRF AND 3-KM HRRR INDICATE A TRANSITION FROM THE
WESTERLY UPSLOPE SNOW SHOWERS OVER THE WRN DACKS TO AN ORGANIZED
SINGLE BAND. BUFKIT PROFILES JUST DOWNSTREAM OF LAKE ONTARIO
INDICATED MODERATE INSTABILITY WITH AN INVERSION HEIGHT CLOSE TO
10 KFT. HOWEVER...THE BAND IS EXPECTED TO FORM AND QUICKLY
TRANSITION S/SE WITH THE STRONG VEERING WIND PROFILE IN THE
BOUNDARY LAYER. THE LOW LEVEL FLOW STARTS AT 260-270 DEGS AND THEN
SHIFTS TO A 280 TO 290 DEG LOW-LEVEL TRAJECTORY. A QUICK BLAST OF
HVY SNOW SHOWERS IS ANTICIPATED FOR THE WRN DACKS WITH 3 TO 6
INCHES OF SNOW WITH PERHAPS SOME 4 TO 8 INCH AMOUNTS JUST SOUTH OF
OLD FORGE AND INLET. THE TRANSITORY BAND MOVES INTO SRN HERKIMER
COUNTY...AND THE W-CNTRL MOHAWK VALLEY BTWN 4-7 AM. THE NAM AND
HIRES WRF SHOW A MULTI-LAKE CONNECTION WITH MDT INSTABILITY CLASS
AT KUCA BUFKIT PROFILE. THIS AREA MAY NEED AN UPGRADE LATER...BUT
WE PUT THE ENTIRE W-CNTRL MOHAWK VALLEY CORRIDOR WAS ALSO PLACED
IN A LAKE EFFECT SNOW ADVISORY FOR SNOW AND BLOWING SNOW. ADVISORY
WIND LEVEL GUSTS WILL BE CLOSE WITH 35 TO 45 MPH GUSTS FORECASTED.
LOWS WILL BE MUCH COLDER IN THE TEENS TO M20S WITH SOME SINGLE
DIGITS OVER THE ADIRONDACK PARK...AND U20S OVER THE MID HUDSON
VALLEY.
MONDAY...THE BETTER PRESSURE RISES PASS NORTH OF ST LAWRENCE RIVER
VALLEY AND NRN NY BTWN 12Z-18Z MON 8-10 HPA/6 HRS. THE ISALLOBARIC
COUPLET IS IMPRESSIVE AS THE CYCLONE DEEPENS AND INTENSIFIES TO
ABOUT 980 HPA OVER THE GULF OF ST LAWRENCE BY 12Z/MON. SOME
SUSTAINED WESTERLY WINDS OF 15 TO 25 MPH WITH GUSTS 35 TO 45 MPH
ARE EXPECTED. THE 10-M WINDS ON THE GFSMOS PRODUCT FOR KALB ARE
IMPRESSIVE IN THE 18-24 KT SUSTAINED RANGE. THE BUFKIT MOMENTUM
TRANSFER PROFILES SHOW 40 KTS WILL NEED TO MIXED FROM 2.5 KFT AGL
FOR WIND ADVISORY CRITERIA TO BE MET. ANY WIND FLAGS WILL BE
MONITORED BY LATER SHIFTS. IT DOES LOOK PLAUSIBLE THAT SOME LAKE
EFFECT SHOWERS MAY SNEAK DOWN THE MOHAWK RIVER VALLEY INTO THE
CAPITAL REGION AND NRN TACONICS. HIGH CHC AND LIKELY POPS WERE USED
LATE MONDAY MORNING INTO THE PM FOR A COATING TO PERHAPS A HALF AN
INCH OF SNOW. SOME OF THE UPSLOPE AREAS OF THE SRN GREENS IN THE
SRN VT...TACONICS...AND NRN BERKS COULD GET AN INCH OR TWO OR
SNOW. THE ADVISORY AREA HIGHLIGHTED WILL LIKELY RECEIVE 3 TO 6
INCHES WITH SOME ISOLATED 4 TO 8 INCH AMOUNTS. THE INVERSION
HEIGHTS DO LOWER IN THE AFTERNOON...AND THE SHEAR INCREASES SO THE
DOWNSTREAM TRAJECTORY WILL DECREASE. MAX TEMPS MAY BE IN THE
MORNING...AND TEMPS MAY CONTINUE TO FALL SLOWLY IN THE AFTERNOON
IN THE POTENT COLD ADVECTION REGIME...AS H850 TEMPS CRASH INTO THE
-17C TO -22C RANGE ACROSS THE FCST AREA. DAYTIME HIGHS WILL BE IN
THE M20S TO L30S FROM THE TRI CITIES SOUTH AND EAST...AND TEENS TO
L20S NORTH AND WEST WITH SOME SINGLE NUMBERS OVER THE SRN DACKS.
WIND CHILLS WILL RANGE FROM 10 BELOW TO 10 ABOVE ZERO.
MONDAY NIGHT...LAKE EFFECT SNOW BAND LIFTS BACK NORTHWARD...AS THE FLOW
BACKS WITH AN APPROACHING SHORT-WAVE/CLIPPER LOW FROM THE GREAT
LAKES REGION AND MIDWEST. HIGH PRESSURE BRIEFLY BUILDS IN FROM
QUEBEC WITH A VERY COLD NIGHT EXPECTED. THE WINDS SHOULD
DIMINISH...AND FRIGID TEMPS ARE ANTICIPATED WITH LOWS BELOW ZERO
OVER THE SRN DACKS...AND PARTS OF THE LAKE REGION REGION...AND
ZERO TO 10 ABOVE IN MOST OTHER LOCATIONS WITH SOME LOWER TEENS IN
THE CAPITAL DISTRICT AND MID HUDSON VALLEY.
CLOUDS WILL INCREASE IN THE FRIGID AIR MASS WITH THE BETTER CHANCE
FOR LIGHT SNOW AND SCT SNOW SHOWERS ON TUE.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
VERY COLD TEMPERATURES AND ACTIVE WEATHER THIS WEEK...WITH THE
COLDEST TEMPERATURES OF THE WINTER EXPECTED WEDNESDAY NIGHT AND
THURSDAY WITH LIFE-THREATENING WIND CHILLS POSSIBLE.
A QUICK MOVING NORTHERN STREAM CLIPPER SYSTEM WILL BRING A PERIOD OF
LIGHT SNOW TO THE AREA TUESDAY. THIS SYSTEM IS EXPECTED TO PASS OVER
THE OHIO VALLEY AND MOVE OFF THE DELMARVA. IT WILL HAVE LIMITED
MOISTURE BUT GOOD FORCING. LOOKING AT HIGH RATIO SNOWFALL. AT THIS
TIME EXPECT BELOW ADVISORY LEVEL ACCUMULATIONS. HIGHS WILL BE AROUND
10 DEGREES BELOW NORMAL.
THE NEXT QUICK MOVING LOW PRESSURE SYSTEM AND NORTHERN STREAM SHORT
WAVE WILL BE IN ITS HEELS. WILL HAVE CONTINUING CHANCES FOR SNOW
SHOWERS TUESDAY NIGHT WITH SOME LAKE EFFECT/ENHANCEMENT INTO THE
WESTERN ADIRONDACKS. EXPECT SNOW SHOWERS AND POSSIBLY SNOW SQUALLS
AS THE ARCTIC BOUNDARY APPROACHES AND MOVES THROUGH WEDNESDAY. THIS
SYSTEM/FRONT WILL BE THE ONE THAT OPENS THE DOOR TO THE ARCTIC
AIRMASS WITH ITS PASSAGE STRONG COLD AIR ADVECTION WILL BEGIN.
850 MB TEMPERATURES ARE MODELED TO DROP TO -25 TO -30 DEGREES
CELSIUS ACROSS THE FORECAST AREA WEDNESDAY NIGHT. SURFACE
TEMPERATURES ARE FORECAST TO PLUMMET RANGING FROM AROUND 1 DEGREES
TO AROUND 20 DEGREES BELOW ZERO...AROUND 20 DEGREES BELOW NORMAL. IN
ADDITION...THE PRESSURE GRADIENT ACROSS THE REGION WILL BE TIGHT
BETWEEN THE DEPARTING LOW PRESSURE SYSTEM AND AN ADVANCING HIGH
RESULTING IN BRISK AND GUSTY NORTHWEST WINDS. THE COMBINATION OF THE
BITTER TEMPERATURES AND BRISK WINDS WILL RESULT IN DANGEROUS TO
LIFE-THREATENING WIND CHILL VALUES WEDNESDAY NIGHT INTO THURSDAY
MORNING. WILL KEEP MENTION IN THE HAZARDOUS WEATHER OUTLOOK.
THURSDAY WILL BE A FRIGID DAY WITH SOME HIGHER PRESSURE BUILDING IN.
TEMPERATURES WILL REMAIN AROUND 20 DEGREES BELOW NORMAL. THE LAST
TIME IS WAS THIS COLD WAS BACK ON JANUARY 22 2014...THE HIGH
TEMPERATURE IN ALBANY WAS ONLY 9 DEGREES WITH A LOW OF 6 DEGREES
BELOW ZERO. LOOKING AT SIMILAR VALUES. WITH NORTHWEST FLOW ACROSS
THE GREAT LAKES WOULD EXPECT MULTI BANDS ACROSS CENTRAL NEW YORK
WHICH COULD MAY REACH INTO THE FAR WESTERN PORTION OF THE FORECAST
AREA.
YET ANOTHER NORTHERN STREAM SYSTEM WILL APPROACH LATE IN THE WEEK
BRINGING MORE CHANCES FOR SNOW SHOWERS TO THE AREA. TEMPERATURES
WILL MODERATE SOME IN THE SOUTHWEST FLOW AHEAD OF THE APPROACHING
SYSTEM HOWEVER THEY WILL REMAIN WELL BELOW NORMAL. THE COLDEST AIR
IS EXPECTED TO REMAIN TO OUR NORTH PASSING OVER EASTERN CANADA ITS
IN WAKE AS WE HEAD INTO THE WEEKEND. COULD BE LOOKING AT MORE LAKE
EFFECT IN THE WAKE OF THE SYSTEM.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
BOUNDARY LAYER CONTINUES TO STRUGGLES TO WARM. TEMPERATURES ARE
ABOVE FREEZING AT KPOU AND KALB. HOWEVER AT KPSF IS NOW 32 DEGREES
AND KGFL 31 DEGREES. MORE STEADY PRECIPITATION HAS OVERSPREAD THE
AREA EARLY THIS MORNING AHEAD OF THE SURFACE LOW OVER THE EASTERN
GREAT LAKES AND ITS ASSOCIATED WARM FRONT WHICH IS CAUGHT UP IN THE
APPALACHIANS. THE WARM FRONT WILL BE FORCED ACROSS THE AREA THIS
MORNING WITH THE SYSTEM`S COLD FRONT SWEEPING THROUGH THIS AFTERNOON
INTO THE EVENING AS THE SURFACE LOW PASSES TO OUR NORTH.
IFR CONDITIONS WILL PERSIST AS A WARM FRONT APPROACHES. THE AREA
SHOULD BRIEFLY GET INTO THE WARM SECTOR OF THE LOW PRESSURE SYSTEM
WITH CHANCES FOR SHOWERS CONTINUING WITH THE BETTER CHANCES AS THE
COLD FRONT MOVES THROUGH. CONDITIONS/CEILINGS WILL LIFT WITH THE
PASSAGE OF THE COLD FRONT.
WINDS WILL SHIFT TOWARD THE SOUTH WITH THE PASSAGE OF THE WARM FRONT
AND INCREASE IN SPEED. THEY WILL SHIFT TOWARD THE WEST WITH THE
PASSAGE OF THE COLD FRONT AND BECOME GUSTY. HAVE KEPT LOW LEVEL WIND
SHEAR IN KPOU TAF THROUGH MUCH OF THE DAY.
OUTLOOK...
MON NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUE: MODERATE OPERATIONAL IMPACT. LIKELY SN.
TUE NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
WED: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF SHSN.
WED NIGHT: LOW OPERATIONAL IMPACT. BREEZY.
THU: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
A COMPLEX STORM SYSTEM WITH MODERATE TO HEAVY QPF WILL MOVE ACROSS
THE HSA THROUGH TODAY.
MOST AREAS ARE FORECAST TO RECEIVE 1-2 INCHES OF LIQUID
EQUIVALENT PRECIPITATION...WITH LOCALLY IN EXCESS OF TWO INCHES.
THIS WILL ALLOW FOR SIGNIFICANT RISES ON RIVERS AND STREAMS ON
SUNDAY...AS TEMPERATURES RISE ABOVE FREEZING BRIEFLY OVER THE
ENTIRE REGION.
ISOLATED MINOR FLOODING IS POSSIBLE AND PER COLLABORATION
YESTERDAY WITH THE NERFC...THE HSA POINTS THAT GOES ABOVE ACTION
STAGE ARE WILLIAMSTOWN /WILM3/...AND GRANVILLE /GVVN6/ AT THIS
TIME. SINCE THE POTENTIAL OF WIDESPREAD MINOR FLOODING IS NOT
EXPECTED...A FLOOD WATCH HAS NOT BEEN ISSUED AT THIS TIME.
LAKE EFFECT SNOWFALL WILL IMPACT LOCATIONS NORTH AND WEST OF THE
CAPITAL REGION TONIGHT THROUGH MONDAY IN THE WAKE OF A STRONG COLD
FRONT.
THEREAFTER...BITTER COLD WEATHER IS EXPECTED NEXT WEEK. SOME
FREEZE UP ICE JAMS ARE POSSIBLE ACROSS THE SOUTHWESTERN
ADIRONDACKS AND SOUTHERN VERMONT BY LATE IN THE WEEK.
OTHERWISE...ICE WILL LIKELY DEVELOP AND INCREASE ACROSS RIVERS
AND STREAMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...LAKE EFFECT SNOW ADVISORY FROM 4 AM TO 7 PM EST MONDAY FOR
NYZ038>040-082.
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST
MONDAY FOR NYZ032-033.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...FRUGIS/WASULA
SHORT TERM...WASULA
LONG TERM...IAA
AVIATION...IAA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
701 AM EST SUN JAN 4 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE FROM THE EASTERN GREAT LAKES
REGION TO SOUTHERN QUEBEC TODAY. A STRONG COLD FRONT WILL MOVE
ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND LATE THIS AFTERNOON
INTO TONIGHT WITH RAIN SHOWERS TRANSITIONING TO SNOW SHOWERS.
BLUSTERY AND COLD CONDITIONS WILL OPEN THE WORK WEEK WITH LAKE
EFFECT SNOW SHOWERS MAINLY NORTH AND WEST OF THE GREATER CAPITAL
REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 653 AM EST...THE ADVISORIES HAVE BEEN EXTENDED UNTIL 9 AM
FOR PORTIONS OF THE CAPITAL REGION...UPPER HUDSON VALLEY...AND THE
MOHAWK RIVER VALLEY...AS TEMPS ARE STRUGGLING TO RISE ABOVE THE
FREEZING MARK. THE WARNINGS ALSO GO UNTIL 9 AM. A REPORT OF A
QUARTER INCH OF ICE CAME IN FROM PERU IN THE BERKSHIRES. BASED ON
THE RADAR RETURNS WOULD BE SURPRISED IF THERE ARE OTHER QUARTER TO
THIRD OF AN INCH ICE AMOUNTS EAST OF THE SRN GREENS...AND SRN
DACKS.
IN THE SW FLOW ALOFT ANOTHER SHORT-WAVE AHEAD OF THE WARM FRONT
HAS ALLOWED THE PCPN TO BLOSSOM AGAIN OVER MOST OF THE FCST AREA.
THE CATEGORICAL POPS WERE MAINTAINED FOR MOST OF THE MORNING.
THE TREND WILL BE FOR THE TEMPS TO RISE ABOVE FREEZING BTWN 6 AM
AND 9 AM. ANY ADDITIONAL ICE ACCRETIONS WILL BE A COATING TO A
TENTH OF AN INCH WHERE THE STATEMENTS ARE STILL UP.
THE STRONG LLJ WITH THE SURGE OF GULF AND ATLANTIC MOISTURE IS NOW
LIFTING NORTH AND EAST OF THE REGION...AS LOW PRESSURE MOVES INTO
THE CNTRL-ERN GREAT LAKES REGION THIS MORNING. THE H850 WINDS ARE
SHIFTING TO THE SW FOR THE LATE MORNING INTO THE AFTERNOON. THE
WARM FRONT WILL TRY TO BREAK THROUGH MOST OF THE REGION WITH ONE
MORE SURGE OF WARM ADVECTION PCPN EXPECTED. THERE MAYBE ANOTHER
LULL IN THE PCPN IN THE LATE MORNING INTO THE AFTERNOON...AS THE
FCST AREA WILL BE IN A WARM SECTOR. EXPECT PLENTY OF CLOUDS TO BE
AROUND AND H850 TEMPS TO RISE TO +7C TO +10C. OUR MAX TEMPS
REFLECT THE METMOS VALUES WITH M40S TO L50S ACROSS THE REGION.
IT APPEARS A PREFRONTAL TROUGH WILL MOVE ACROSS THE REGION IN THE
LATE AFTERNOON AND THE COLD FRONT WILL APPROACH FOR THE EARLY
EVENING. THE LLJ AT H850 INCREASES TO 45-60 KTS AHEAD OF THE COLD
FRONT...AS THE SFC WAVE MOVES INTO SRN QUEBEC. THE CYCLONE DOES
DEEPEN TO CLOSE TO 990 HPA BY 00Z/MON. THE 6-HR PRESSURE FALLS ARE
EXPECTED TO BE OVER SE QUEBEC AND NRN NEW ENGLAND. THE H925 WINDS
AHEAD AND JUST BEHIND THE FRONT CONTINUE TO BE STRONG AT 30-40
KTS...BUT MIXING DOWN 40 KTS IN THE EARLY EVENING MAY BE
DIFFICULT. WE WILL CONTINUE TO HAVE SOME GUSTS TO 30 TO 40 WITH A
BURST OF SHOWERS WITH THE FRONT. EXPECT THE SHOWERS TO TRANSITION
TO SNOW SHOWERS ACROSS THE WRN DACKS IN THE EARLY EVENING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
LAKE EFFECT SNOW ADVISORY ISSUED FROM 7 PM SUNDAY TO 7 AM
MONDAY FOR NORTHERN HERKIMER AND HAMILTON COUNTIES...
LAKE EFFECT SNOW ADVISORY ISSUED FROM 4 AM MONDAY TO 7 PM
MONDAY FOR SOUTHERN HERKIMER...FULTON AND MONTGOMERY COUNTIES.
THE ADVISORIES ARE FOR SNOW AND BLOWING SNOW WITH GUSTY WINDS OF
35 TO 45 MPH.
OUR CONFIDENCE WAS NOT GREAT ENOUGH TO ISSUE A WIND ADVISORY FOR
PARTS OF THE REGION SUNDAY NIGHT...THOUGH A 3RD PERIOD ADVISORY
MAY BE NEEDED FOR MONDAY...AS BETTER MOMENTUM TRANSFER IS
EXPECTED...BUT FOR NOW WIDESPREAD 46-57 MPH WIND GUSTS ARE NOT
ANTICIPATED FOR SUNDAY NIGHT INTO MONDAY. THIS WILL CONTINUE TO BE
MONITORED.
TONIGHT...COLD FRONT MOVES ACROSS THE REGION WITH STRONG LOW LEVEL
COLD ADVECTION EXPECTED. WESTERLY UPSLOPE SNOW SHOWERS WILL
INITIALLY IMPACT THE WRN DACKS AND SRN GREENS MTNS WITH MORE SCT
RAIN AND SNOW SHOWER ACTIVITY AWAY FROM THESE AREAS.
THE LATEST HIRES WRF AND 3-KM HRRR INDICATE A TRANSITION FROM THE
WESTERLY UPSLOPE SNOW SHOWERS OVER THE WRN DACKS TO AN ORGANIZED
SINGLE BAND. BUFKIT PROFILES JUST DOWNSTREAM OF LAKE ONTARIO
INDICATED MODERATE INSTABILITY WITH AN INVERSION HEIGHT CLOSE TO
10 KFT. HOWEVER...THE BAND IS EXPECTED TO FORM AND QUICKLY
TRANSITION S/SE WITH THE STRONG VEERING WIND PROFILE IN THE
BOUNDARY LAYER. THE LOW LEVEL FLOW STARTS AT 260-270 DEGS AND THEN
SHIFTS TO A 280 TO 290 DEG LOW-LEVEL TRAJECTORY. A QUICK BLAST OF
HVY SNOW SHOWERS IS ANTICIPATED FOR THE WRN DACKS WITH 3 TO 6
INCHES OF SNOW WITH PERHAPS SOME 4 TO 8 INCH AMOUNTS JUST SOUTH OF
OLD FORGE AND INLET. THE TRANSITORY BAND MOVES INTO SRN HERKIMER
COUNTY...AND THE W-CNTRL MOHAWK VALLEY BTWN 4-7 AM. THE NAM AND
HIRES WRF SHOW A MULTI-LAKE CONNECTION WITH MDT INSTABILITY CLASS
AT KUCA BUFKIT PROFILE. THIS AREA MAY NEED AN UPGRADE LATER...BUT
WE PUT THE ENTIRE W-CNTRL MOHAWK VALLEY CORRIDOR WAS ALSO PLACED
IN A LAKE EFFECT SNOW ADVISORY FOR SNOW AND BLOWING SNOW. ADVISORY
WIND LEVEL GUSTS WILL BE CLOSE WITH 35 TO 45 MPH GUSTS FORECASTED.
LOWS WILL BE MUCH COLDER IN THE TEENS TO M20S WITH SOME SINGLE
DIGITS OVER THE ADIRONDACK PARK...AND U20S OVER THE MID HUDSON
VALLEY.
MONDAY...THE BETTER PRESSURE RISES PASS NORTH OF ST LAWRENCE RIVER
VALLEY AND NRN NY BTWN 12Z-18Z MON 8-10 HPA/6 HRS. THE ISALLOBARIC
COUPLET IS IMPRESSIVE AS THE CYCLONE DEEPENS AND INTENSIFIES TO
ABOUT 980 HPA OVER THE GULF OF ST LAWRENCE BY 12Z/MON. SOME
SUSTAINED WESTERLY WINDS OF 15 TO 25 MPH WITH GUSTS 35 TO 45 MPH
ARE EXPECTED. THE 10-M WINDS ON THE GFSMOS PRODUCT FOR KALB ARE
IMPRESSIVE IN THE 18-24 KT SUSTAINED RANGE. THE BUFKIT MOMENTUM
TRANSFER PROFILES SHOW 40 KTS WILL NEED TO MIXED FROM 2.5 KFT AGL
FOR WIND ADVISORY CRITERIA TO BE MET. ANY WIND FLAGS WILL BE
MONITORED BY LATER SHIFTS. IT DOES LOOK PLAUSIBLE THAT SOME LAKE
EFFECT SHOWERS MAY SNEAK DOWN THE MOHAWK RIVER VALLEY INTO THE
CAPITAL REGION AND NRN TACONICS. HIGH CHC AND LIKELY POPS WERE USED
LATE MONDAY MORNING INTO THE PM FOR A COATING TO PERHAPS A HALF AN
INCH OF SNOW. SOME OF THE UPSLOPE AREAS OF THE SRN GREENS IN THE
SRN VT...TACONICS...AND NRN BERKS COULD GET AN INCH OR TWO OR
SNOW. THE ADVISORY AREA HIGHLIGHTED WILL LIKELY RECEIVE 3 TO 6
INCHES WITH SOME ISOLATED 4 TO 8 INCH AMOUNTS. THE INVERSION
HEIGHTS DO LOWER IN THE AFTERNOON...AND THE SHEAR INCREASES SO THE
DOWNSTREAM TRAJECTORY WILL DECREASE. MAX TEMPS MAY BE IN THE
MORNING...AND TEMPS MAY CONTINUE TO FALL SLOWLY IN THE AFTERNOON
IN THE POTENT COLD ADVECTION REGIME...AS H850 TEMPS CRASH INTO THE
-17C TO -22C RANGE ACROSS THE FCST AREA. DAYTIME HIGHS WILL BE IN
THE M20S TO L30S FROM THE TRI CITIES SOUTH AND EAST...AND TEENS TO
L20S NORTH AND WEST WITH SOME SINGLE NUMBERS OVER THE SRN DACKS.
WIND CHILLS WILL RANGE FROM 10 BELOW TO 10 ABOVE ZERO.
MONDAY NIGHT...LAKE EFFECT SNOW BAND LIFTS BACK NORTHWARD...AS THE FLOW
BACKS WITH AN APPROACHING SHORT-WAVE/CLIPPER LOW FROM THE GREAT
LAKES REGION AND MIDWEST. HIGH PRESSURE BRIEFLY BUILDS IN FROM
QUEBEC WITH A VERY COLD NIGHT EXPECTED. THE WINDS SHOULD
DIMINISH...AND FRIGID TEMPS ARE ANTICIPATED WITH LOWS BELOW ZERO
OVER THE SRN DACKS...AND PARTS OF THE LAKE REGION REGION...AND
ZERO TO 10 ABOVE IN MOST OTHER LOCATIONS WITH SOME LOWER TEENS IN
THE CAPITAL DISTRICT AND MID HUDSON VALLEY.
CLOUDS WILL INCREASE IN THE FRIGID AIR MASS WITH THE BETTER CHANCE
FOR LIGHT SNOW AND SCT SNOW SHOWERS ON TUE.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
VERY COLD TEMPERATURES AND ACTIVE WEATHER THIS WEEK...WITH THE
COLDEST TEMPERATURES OF THE WINTER EXPECTED WEDNESDAY NIGHT AND
THURSDAY WITH LIFE-THREATENING WIND CHILLS POSSIBLE.
A QUICK MOVING NORTHERN STREAM CLIPPER SYSTEM WILL BRING A PERIOD OF
LIGHT SNOW TO THE AREA TUESDAY. THIS SYSTEM IS EXPECTED TO PASS OVER
THE OHIO VALLEY AND MOVE OFF THE DELMARVA. IT WILL HAVE LIMITED
MOISTURE BUT GOOD FORCING. LOOKING AT HIGH RATIO SNOWFALL. AT THIS
TIME EXPECT BELOW ADVISORY LEVEL ACCUMULATIONS. HIGHS WILL BE AROUND
10 DEGREES BELOW NORMAL.
THE NEXT QUICK MOVING LOW PRESSURE SYSTEM AND NORTHERN STREAM SHORT
WAVE WILL BE IN ITS HEELS. WILL HAVE CONTINUING CHANCES FOR SNOW
SHOWERS TUESDAY NIGHT WITH SOME LAKE EFFECT/ENHANCEMENT INTO THE
WESTERN ADIRONDACKS. EXPECT SNOW SHOWERS AND POSSIBLY SNOW SQUALLS
AS THE ARCTIC BOUNDARY APPROACHES AND MOVES THROUGH WEDNESDAY. THIS
SYSTEM/FRONT WILL BE THE ONE THAT OPENS THE DOOR TO THE ARCTIC
AIRMASS WITH ITS PASSAGE STRONG COLD AIR ADVECTION WILL BEGIN.
850 MB TEMPERATURES ARE MODELED TO DROP TO -25 TO -30 DEGREES
CELSIUS ACROSS THE FORECAST AREA WEDNESDAY NIGHT. SURFACE
TEMPERATURES ARE FORECAST TO PLUMMET RANGING FROM AROUND 1 DEGREES
TO AROUND 20 DEGREES BELOW ZERO...AROUND 20 DEGREES BELOW NORMAL. IN
ADDITION...THE PRESSURE GRADIENT ACROSS THE REGION WILL BE TIGHT
BETWEEN THE DEPARTING LOW PRESSURE SYSTEM AND AN ADVANCING HIGH
RESULTING IN BRISK AND GUSTY NORTHWEST WINDS. THE COMBINATION OF THE
BITTER TEMPERATURES AND BRISK WINDS WILL RESULT IN DANGEROUS TO
LIFE-THREATENING WIND CHILL VALUES WEDNESDAY NIGHT INTO THURSDAY
MORNING. WILL KEEP MENTION IN THE HAZARDOUS WEATHER OUTLOOK.
THURSDAY WILL BE A FRIGID DAY WITH SOME HIGHER PRESSURE BUILDING IN.
TEMPERATURES WILL REMAIN AROUND 20 DEGREES BELOW NORMAL. THE LAST
TIME IS WAS THIS COLD WAS BACK ON JANUARY 22 2014...THE HIGH
TEMPERATURE IN ALBANY WAS ONLY 9 DEGREES WITH A LOW OF 6 DEGREES
BELOW ZERO. LOOKING AT SIMILAR VALUES. WITH NORTHWEST FLOW ACROSS
THE GREAT LAKES WOULD EXPECT MULTI BANDS ACROSS CENTRAL NEW YORK
WHICH COULD MAY REACH INTO THE FAR WESTERN PORTION OF THE FORECAST
AREA.
YET ANOTHER NORTHERN STREAM SYSTEM WILL APPROACH LATE IN THE WEEK
BRINGING MORE CHANCES FOR SNOW SHOWERS TO THE AREA. TEMPERATURES
WILL MODERATE SOME IN THE SOUTHWEST FLOW AHEAD OF THE APPROACHING
SYSTEM HOWEVER THEY WILL REMAIN WELL BELOW NORMAL. THE COLDEST AIR
IS EXPECTED TO REMAIN TO OUR NORTH PASSING OVER EASTERN CANADA ITS
IN WAKE AS WE HEAD INTO THE WEEKEND. COULD BE LOOKING AT MORE LAKE
EFFECT IN THE WAKE OF THE SYSTEM.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
BOUNDARY LAYER CONTINUES TO STRUGGLES TO WARM. TEMPERATURES ARE
ABOVE FREEZING AT KPOU AND KALB. HOWEVER AT KPSF IS NOW 32 DEGREES
AND KGFL 31 DEGREES. MORE STEADY PRECIPITATION HAS OVERSPREAD THE
AREA EARLY THIS MORNING AHEAD OF THE SURFACE LOW OVER THE EASTERN
GREAT LAKES AND ITS ASSOCIATED WARM FRONT WHICH IS CAUGHT UP IN THE
APPALACHIANS. THE WARM FRONT WILL BE FORCED ACROSS THE AREA THIS
MORNING WITH THE SYSTEM`S COLD FRONT SWEEPING THROUGH THIS AFTERNOON
INTO THE EVENING AS THE SURFACE LOW PASSES TO OUR NORTH.
IFR CONDITIONS WILL PERSIST AS A WARM FRONT APPROACHES. THE AREA
SHOULD BRIEFLY GET INTO THE WARM SECTOR OF THE LOW PRESSURE SYSTEM
WITH CHANCES FOR SHOWERS CONTINUING WITH THE BETTER CHANCES AS THE
COLD FRONT MOVES THROUGH. CONDITIONS/CEILINGS WILL LIFT WITH THE
PASSAGE OF THE COLD FRONT.
WINDS WILL SHIFT TOWARD THE SOUTH WITH THE PASSAGE OF THE WARM FRONT
AND INCREASE IN SPEED. THEY WILL SHIFT TOWARD THE WEST WITH THE
PASSAGE OF THE COLD FRONT AND BECOME GUSTY. HAVE KEPT LOW LEVEL WIND
SHEAR IN KPOU TAF THROUGH MUCH OF THE DAY.
OUTLOOK...
MON NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUE: MODERATE OPERATIONAL IMPACT. LIKELY SN.
TUE NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
WED: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF SHSN.
WED NIGHT: LOW OPERATIONAL IMPACT. BREEZY.
THU: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
A COMPLEX STORM SYSTEM WITH MODERATE TO HEAVY QPF WILL MOVE ACROSS
THE HSA THROUGH TODAY.
MOST AREAS ARE FORECAST TO RECEIVE 1-2 INCHES OF LIQUID
EQUIVALENT PRECIPITATION...WITH LOCALLY IN EXCESS OF TWO INCHES.
THIS WILL ALLOW FOR SIGNIFICANT RISES ON RIVERS AND STREAMS ON
SUNDAY...AS TEMPERATURES RISE ABOVE FREEZING BRIEFLY OVER THE
ENTIRE REGION.
ISOLATED MINOR FLOODING IS POSSIBLE AND PER COLLABORATION
YESTERDAY WITH THE NERFC...THE HSA POINTS THAT GOES ABOVE ACTION
STAGE ARE WILLIAMSTOWN /WILM3/...AND GRANVILLE /GVVN6/ AT THIS
TIME. SINCE THE POTENTIAL OF WIDESPREAD MINOR FLOODING IS NOT
EXPECTED...A FLOOD WATCH HAS NOT BEEN ISSUED AT THIS TIME.
LAKE EFFECT SNOWFALL WILL IMPACT LOCATIONS NORTH AND WEST OF THE
CAPITAL REGION TONIGHT THROUGH MONDAY IN THE WAKE OF A STRONG COLD
FRONT.
THEREAFTER...BITTER COLD WEATHER IS EXPECTED NEXT WEEK. SOME
FREEZE UP ICE JAMS ARE POSSIBLE ACROSS THE SOUTHWESTERN
ADIRONDACKS AND SOUTHERN VERMONT BY LATE IN THE WEEK.
OTHERWISE...ICE WILL LIKELY DEVELOP AND INCREASE ACROSS RIVERS
AND STREAMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR CTZ001.
NY...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR NYZ032-
038>040-048>050-053-054-084.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR NYZ033-
041>043-082-083.
LAKE EFFECT SNOW ADVISORY FROM 4 AM TO 7 PM EST MONDAY FOR
NYZ038>040-082.
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST
MONDAY FOR NYZ032-033.
MA...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR MAZ001-
025.
VT...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR VTZ013.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR VTZ014-
015.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...IAA
AVIATION...IAA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
653 AM EST SUN JAN 4 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE FROM THE EASTERN GREAT LAKES
REGION TO SOUTHERN QUEBEC TODAY. A STRONG COLD FRONT WILL MOVE
ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND LATE THIS AFTERNOON
INTO TONIGHT WITH RAIN SHOWERS TRANSITIONING TO SNOW SHOWERS.
BLUSTERY AND COLD CONDITIONS WILL OPEN THE WORK WEEK WITH LAKE
EFFECT SNOW SHOWERS MAINLY NORTH AND WEST OF THE GREATER CAPITAL
REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 653 AM EST...THE ADVISORIES HAVE BEEN EXTENDED UNTIL 9 AM
FOR PORTIONS OF THE CAPITAL REGION...UPPER HUDSON VALLEY...AND THE
MOHAWK RIVER VALLEY...AS TEMPS ARE STRUGGLING TO RISE ABOVE THE
FREEZING MARK. THE WARNINGS ALSO GO UNTIL 9 AM. A REPORT OF A
QUARTER INCH OF ICE CAME IN FROM PERU IN THE BERKSHIRES. BASED ON
THE RADAR RETURNS WOULD BE SURPRISED IF THERE ARE OTHER QUARTER TO
THIRD OF AN INCH ICE AMOUNTS EAST OF THE SRN GREENS...AND SRN
DACKS.
IN THE SW FLOW ALOFT ANOTHER SH0RT-WAVE AHEAD OF THE WARM FRONT
HAS ALLOWED THE PCPN TO BLOSSOM AGAIN OVER MOST OF THE FCST AREA.
THE CATEGORICAL POPS WERE MAINTAINED FOR MOST OF THE MORNING.
THE TREND WILL BE FOR THE TEMPS TO RISE ABOVE FREEZING BTWN 6 AM
AND 9 AM. ANY ADDITIONAL ICE ACCRETIONS WILL BE A COATING TO A
TENTH OF AN INCH WHERE THE STATEMENTS ARE STILL UP.
THE STRONG LLJ WITH THE SURGE OF GULF AND ATLANTIC MOISTURE IS NOW
LIFTING NORTH AND EAST OF THE REGION...AS LOW PRESSURE MOVES INTO
THE CNTRL-ERN GREAT LAKES REGION THIS MORNING. THE H850 WINDS ARE
SHIFTING TO THE SW FOR THE LATE MORNING INTO THE AFTERNOON. THE
WARM FRONT WILL TRY TO BREAK THROUGH MOST OF THE REGION WITH ONE
MORE SURGE OF WARM ADVECTION PCPN EXPECTED. THERE MAYBE ANOTHER
LULL IN THE PCPN IN THE LATE MORNING INTO THE AFTERNOON...AS THE
FCST AREA WILL BE IN A WARM SECTOR. EXPECT PLENTY OF CLOUDS TO BE
AROUND AND H850 TEMPS TO RISE TO +7C TO +10C. OUR MAX TEMPS
REFLECT THE METMOS VALUES WITH M40S TO L50S ACROSS THE REGION.
IT APPEARS A PREFRONTAL TROUGH WILL MOVE ACROSS THE REGION IN THE
LATE AFTERNOON AND THE COLD FRONT WILL APPROACH FOR THE EARLY
EVENING. THE LLJ AT H850 INCREASES TO 45-60 KTS AHEAD OF THE COLD
FRONT...AS THE SFC WAVE MOVES INTO SRN QUEBEC. THE CYCLONE DOES
DEEPEN TO CLOSE TO 990 HPA BY 00Z/MON. THE 6-HR PRESSURE FALLS ARE
EXPECTED TO BE OVER SE QUEBEC AND NRN NEW ENGLAND. THE H925 WINDS
AHEAD AND JUST BEHIND THE FRONT CONTINUE TO BE STRONG AT 30-40
KTS...BUT MIXING DOWN 40 KTS IN THE EARLY EVENING MAY BE
DIFFICULT. WE WILL CONTINUE TO HAVE SOME GUSTS TO 30 TO 40 WITH A
BURST OF SHOWERS WITH THE FRONT. EXPECT THE SHOWERS TO TRANSITION
TO SNOW SHOWERS ACROSS THE WRN DACKS IN THE EARLY EVENING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
LAKE EFFECT SNOW ADVISORY ISSUED FROM 7 PM SUNDAY TO 7 AM
MONDAY FOR NORTHERN HERKIMER AND HAMILTON COUNTIES...
LAKE EFFECT SNOW ADVISORY ISSUED FROM 4 AM MONDAY TO 7 PM
MONDAY FOR SOUTHERN HERKIMER...FULTON AND MONTGOMERY COUNTIES.
THE ADVISORIES ARE FOR SNOW AND BLOWING SNOW WITH GUSTY WINDS OF
35 TO 45 MPH.
OUR CONFIDENCE WAS NOT GREAT ENOUGH TO ISSUE A WIND ADVISORY FOR
PARTS OF THE REGION SUNDAY NIGHT...THOUGH A 3RD PERIOD ADVISORY
MAY BE NEEDED FOR MONDAY...AS BETTER MOMENTUM TRANSFER IS
EXPECTED...BUT FOR NOW WIDESPREAD 46-57 MPH WIND GUSTS ARE NOT
ANTICIPATED FOR SUNDAY NIGHT INTO MONDAY. THIS WILL CONTINUE TO BE
MONITORED.
TONIGHT...COLD FRONT MOVES ACROSS THE REGION WITH STRONG LOW LEVEL
COLD ADVECTION EXPECTED. WESTERLY UPSLOPE SNOW SHOWERS WILL
INITIALLY IMPACT THE WRN DACKS AND SRN GREENS MTNS WITH MORE SCT
RAIN AND SNOW SHOWER ACTIVITY AWAY FROM THESE AREAS.
THE LATEST HIRES WRF AND 3-KM HRRR INDICATE A TRANSITION FROM THE
WESTERLY UPSLOPE SNOW SHOWERS OVER THE WRN DACKS TO AN ORGANIZED
SINGLE BAND. BUFKIT PROFILES JUST DOWNSTREAM OF LAKE ONTARIO
INDICATED MODERATE INSTABILITY WITH AN INVERSION HEIGHT CLOSE TO
10 KFT. HOWEVER...THE BAND IS EXPECTED TO FORM AND QUICKLY
TRANSITION S/SE WITH THE STRONG VEERING WIND PROFILE IN THE
BOUNDARY LAYER. THE LOW LEVEL FLOW STARTS AT 260-270 DEGS AND THEN
SHIFTS TO A 280 TO 290 DEG LOW-LEVEL TRAJECTORY. A QUICK BLAST OF
HVY SNOW SHOWERS IS ANTICIPATED FOR THE WRN DACKS WITH 3 TO 6
INCHES OF SNOW WITH PERHAPS SOME 4 TO 8 INCH AMOUNTS JUST SOUTH OF
OLD FORGE AND INLET. THE TRANSITORY BAND MOVES INTO SRN HERKIMER
COUNTY...AND THE W-CNTRL MOHAWK VALLEY BTWN 4-7 AM. THE NAM AND
HIRES WRF SHOW A MULTI-LAKE CONNECTION WITH MDT INSTABILITY CLASS
AT KUCA BUFKIT PROFILE. THIS AREA MAY NEED AN UPGRADE LATER...BUT
WE PUT THE ENTIRE W-CNTRL MOHAWK VALLEY CORRIDOR WAS ALSO PLACED
IN A LAKE EFFECT SNOW ADVISORY FOR SNOW AND BLOWING SNOW. ADVISORY
WIND LEVEL GUSTS WILL BE CLOSE WITH 35 TO 45 MPH GUSTS FORECASTED.
LOWS WILL BE MUCH COLDER IN THE TEENS TO M20S WITH SOME SINGLE
DIGITS OVER THE ADIRONDACK PARK...AND U20S OVER THE MID HUDSON
VALLEY.
MONDAY...THE BETTER PRESSURE RISES PASS NORTH OF ST LAWRENCE RIVER
VALLEY AND NRN NY BTWN 12Z-18Z MON 8-10 HPA/6 HRS. THE ISALLOBARIC
COUPLET IS IMPRESSIVE AS THE CYCLONE DEEPENS AND INTENSIFIES TO
ABOUT 980 HPA OVER THE GULF OF ST LAWRENCE BY 12Z/MON. SOME
SUSTAINED WESTERLY WINDS OF 15 TO 25 MPH WITH GUSTS 35 TO 45 MPH
ARE EXPECTED. THE 10-M WINDS ON THE GFSMOS PRODUCT FOR KALB ARE
IMPRESSIVE IN THE 18-24 KT SUSTAINED RANGE. THE BUFKIT MOMENTUM
TRANSFER PROFILES SHOW 40 KTS WILL NEED TO MIXED FROM 2.5 KFT AGL
FOR WIND ADVISORY CRITERIA TO BE MET. ANY WIND FLAGS WILL BE
MONITORED BY LATER SHIFTS. IT DOES LOOK PLAUSIBLE THAT SOME LAKE
EFFECT SHOWERS MAY SNEAK DOWN THE MOHAWK RIVER VALLEY INTO THE
CAPITAL REGION AND NRN TACONICS. HIGH CHC AND LIKELY POPS WERE USED
LATE MONDAY MORNING INTO THE PM FOR A COATING TO PERHAPS A HALF AN
INCH OF SNOW. SOME OF THE UPSLOPE AREAS OF THE SRN GREENS IN THE
SRN VT...TACONICS...AND NRN BERKS COULD GET AN INCH OR TWO OR
SNOW. THE ADVISORY AREA HIGHLIGHTED WILL LIKELY RECEIVE 3 TO 6
INCHES WITH SOME ISOLATED 4 TO 8 INCH AMOUNTS. THE INVERSION
HEIGHTS DO LOWER IN THE AFTERNOON...AND THE SHEAR INCREASES SO THE
DOWNSTREAM TRAJECTORY WILL DECREASE. MAX TEMPS MAY BE IN THE
MORNING...AND TEMPS MAY CONTINUE TO FALL SLOWLY IN THE AFTERNOON
IN THE POTENT COLD ADVECTION REGIME...AS H850 TEMPS CRASH INTO THE
-17C TO -22C RANGE ACROSS THE FCST AREA. DAYTIME HIGHS WILL BE IN
THE M20S TO L30S FROM THE TRI CITIES SOUTH AND EAST...AND TEENS TO
L20S NORTH AND WEST WITH SOME SINGLE NUMBERS OVER THE SRN DACKS.
WIND CHILLS WILL RANGE FROM 10 BELOW TO 10 ABOVE ZERO.
MONDAY NIGHT...LAKE EFFECT SNOW BAND LIFTS BACK NORTHWARD...AS THE FLOW
BACKS WITH AN APPROACHING SHORT-WAVE/CLIPPER LOW FROM THE GREAT
LAKES REGION AND MIDWEST. HIGH PRESSURE BRIEFLY BUILDS IN FROM
QUEBEC WITH A VERY COLD NIGHT EXPECTED. THE WINDS SHOULD
DIMINISH...AND FRIGID TEMPS ARE ANTICIPATED WITH LOWS BELOW ZERO
OVER THE SRN DACKS...AND PARTS OF THE LAKE REGION REGION...AND
ZERO TO 10 ABOVE IN MOST OTHER LOCATIONS WITH SOME LOWER TEENS IN
THE CAPITAL DISTRICT AND MID HUDSON VALLEY.
CLOUDS WILL INCREASE IN THE FRIGID AIR MASS WITH THE BETTER CHANCE
FOR LIGHT SNOW AND SCT SNOW SHOWERS ON TUE.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
VERY COLD TEMPERATURES AND ACTIVE WEATHER THIS WEEK...WITH THE
COLDEST TEMPERATURES OF THE WINTER EXPECTED WEDNESDAY NIGHT AND
THURSDAY WITH LIFE-THREATENING WIND CHILLS POSSIBLE.
A QUICK MOVING NORTHERN STREAM CLIPPER SYSTEM WILL BRING A PERIOD OF
LIGHT SNOW TO THE AREA TUESDAY. THIS SYSTEM IS EXPECTED TO PASS OVER
THE OHIO VALLEY AND MOVE OFF THE DELMARVA. IT WILL HAVE LIMITED
MOISTURE BUT GOOD FORCING. LOOKING AT HIGH RATIO SNOWFALL. AT THIS
TIME EXPECT BELOW ADVISORY LEVEL ACCUMULATIONS. HIGHS WILL BE AROUND
10 DEGREES BELOW NORMAL.
THE NEXT QUICK MOVING LOW PRESSURE SYSTEM AND NORTHERN STREAM SHORT
WAVE WILL BE IN ITS HEELS. WILL HAVE CONTINUING CHANCES FOR SNOW
SHOWERS TUESDAY NIGHT WITH SOME LAKE EFFECT/ENHANCEMENT INTO THE
WESTERN ADIRONDACKS. EXPECT SNOW SHOWERS AND POSSIBLY SNOW SQUALLS
AS THE ARCTIC BOUNDARY APPROACHES AND MOVES THROUGH WEDNESDAY. THIS
SYSTEM/FRONT WILL BE THE ONE THAT OPENS THE DOOR TO THE ARCTIC
AIRMASS WITH ITS PASSAGE STRONG COLD AIR ADVECTION WILL BEGIN.
850 MB TEMPERATURES ARE MODELED TO DROP TO -25 TO -30 DEGREES
CELSIUS ACROSS THE FORECAST AREA WEDNESDAY NIGHT. SURFACE
TEMPERATURES ARE FORECAST TO PLUMMET RANGING FROM AROUND 1 DEGREES
TO AROUND 20 DEGREES BELOW ZERO...AROUND 20 DEGREES BELOW NORMAL. IN
ADDITION...THE PRESSURE GRADIENT ACROSS THE REGION WILL BE TIGHT
BETWEEN THE DEPARTING LOW PRESSURE SYSTEM AND AN ADVANCING HIGH
RESULTING IN BRISK AND GUSTY NORTHWEST WINDS. THE COMBINATION OF THE
BITTER TEMPERATURES AND BRISK WINDS WILL RESULT IN DANGEROUS TO
LIFE-THREATENING WIND CHILL VALUES WEDNESDAY NIGHT INTO THURSDAY
MORNING. WILL KEEP MENTION IN THE HAZARDOUS WEATHER OUTLOOK.
THURSDAY WILL BE A FRIGID DAY WITH SOME HIGHER PRESSURE BUILDING IN.
TEMPERATURES WILL REMAIN AROUND 20 DEGREES BELOW NORMAL. THE LAST
TIME IS WAS THIS COLD WAS BACK ON JANUARY 22 2014...THE HIGH
TEMPERATURE IN ALBANY WAS ONLY 9 DEGREES WITH A LOW OF 6 DEGREES
BELOW ZERO. LOOKING AT SIMILAR VALUES. WITH NORTHWEST FLOW ACROSS
THE GREAT LAKES WOULD EXPECT MULTI BANDS ACROSS CENTRAL NEW YORK
WHICH COULD MAY REACH INTO THE FAR WESTERN PORTION OF THE FORECAST
AREA.
YET ANOTHER NORTHERN STREAM SYSTEM WILL APPROACH LATE IN THE WEEK
BRINGING MORE CHANCES FOR SNOW SHOWERS TO THE AREA. TEMPERATURES
WILL MODERATE SOME IN THE SOUTHWEST FLOW AHEAD OF THE APPROACHING
SYSTEM HOWEVER THEY WILL REMAIN WELL BELOW NORMAL. THE COLDEST AIR
IS EXPECTED TO REMAIN TO OUR NORTH PASSING OVER EASTERN CANADA ITS
IN WAKE AS WE HEAD INTO THE WEEKEND. COULD BE LOOKING AT MORE LAKE
EFFECT IN THE WAKE OF THE SYSTEM.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
BOUNDARY LAYER STRUGGLES TO WARM. TEMPERATURES REMAIN JUST ABOVE
FREEZING AT KPOU AND KALB WITH 34 DEGREES. HOWEVER AT KPSF
TEMPERATURE HAS ONLY REACHED 32 DEGREES AND AT KGFL 30 DEGREES SO
FREEZING RAIN/FREEZING DRIZZLE CONTINUE TO BE A THREAT EARLY THIS
MORNING. THE STEADY PRECIPITATION MOVED OFF TO THE EAST EARLY THIS
MORNING HOWEVER REGIONAL RADARS TO OUR WEST INDICATE MORE ON THE WAY
AHEAD OF THE SURFACE LOW OVER THE OHIO VALLEY AND ITS ASSOCIATED
WARM FRONT WHICH IS CAUGHT UP IN THE APPALACHIANS. THE WARM FRONT
WILL BE FORCED ACROSS THE AREA THIS MORNING WITH THE SYSTEM`S COLD
FRONT SWEEPING THROUGH THIS AFTERNOON INTO THE EVENING AS THE
SURFACE LOW PASSES TO OUR NORTH.
IFR CONDITIONS WILL PERSIST AS A WARM FRONT APPROACHES. THE AREA
SHOULD BRIEFLY GET INTO THE WARM SECTOR OF THE LOW PRESSURE SYSTEM
WITH CHANCES FOR SHOWERS CONTINUING. CONDITIONS/CEILINGS WILL LIFT
WITH THE PASSAGE OF THE COLD FRONT.
WINDS WILL SHIFT TOWARD THE SOUTH WITH THE PASSAGE OF THE WARM FRONT
AND INCREASE IN SPEED. THEY WILL SHIFT TOWARD THE WEST WITH THE
PASSAGE OF THE COLD FRONT AND BECOME GUSTY. HAVE KEPT LOW LEVEL WIND
SHEAR IN KPOU TAF THROUGH MUCH OF THE DAY.
OUTLOOK...
MON NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUE: MODERATE OPERATIONAL IMPACT. LIKELY SN.
TUE NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
WED: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF SHSN.
WED NIGHT: LOW OPERATIONAL IMPACT. BREEZY.
THU: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
A COMPLEX STORM SYSTEM WITH MODERATE TO HEAVY QPF WILL MOVE ACROSS
THE HSA THROUGH TODAY.
MOST AREAS ARE FORECAST TO RECEIVE 1-2 INCHES OF LIQUID
EQUIVALENT PRECIPITATION...WITH LOCALLY IN EXCESS OF TWO INCHES.
THIS WILL ALLOW FOR SIGNIFICANT RISES ON RIVERS AND STREAMS ON
SUNDAY...AS TEMPERATURES RISE ABOVE FREEZING BRIEFLY OVER THE
ENTIRE REGION.
ISOLATED MINOR FLOODING IS POSSIBLE AND PER COLLABORATION
YESTERDAY WITH THE NERFC...THE HSA POINTS THAT GOES ABOVE ACTION
STAGE ARE WILLIAMSTOWN /WILM3/...AND GRANVILLE /GVVN6/ AT THIS
TIME. SINCE THE POTENTIAL OF WIDESPREAD MINOR FLOODING IS NOT
EXPECTED...A FLOOD WATCH HAS NOT BEEN ISSUED AT THIS TIME.
LAKE EFFECT SNOWFALL WILL IMPACT LOCATIONS NORTH AND WEST OF THE
CAPITAL REGION TONIGHT THROUGH MONDAY IN THE WAKE OF A STRONG COLD
FRONT.
THEREAFTER...BITTER COLD WEATHER IS EXPECTED NEXT WEEK. SOME
FREEZE UP ICE JAMS ARE POSSIBLE ACROSS THE SOUTHWESTERN
ADIRONDACKS AND SOUTHERN VERMONT BY LATE IN THE WEEK.
OTHERWISE...ICE WILL LIKELY DEVELOP AND INCREASE ACROSS RIVERS
AND STREAMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR CTZ001.
NY...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR NYZ032-
038>040-048>050-053-054-084.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR NYZ033-
041>043-082-083.
LAKE EFFECT SNOW ADVISORY FROM 4 AM TO 7 PM EST MONDAY FOR
NYZ038>040-082.
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST
MONDAY FOR NYZ032-033.
MA...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR MAZ001-
025.
VT...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR VTZ013.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR VTZ014-
015.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...IAA
AVIATION...IAA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
536 AM EST SUN JAN 4 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE FROM THE EASTERN GREAT LAKES
REGION TO SOUTHERN QUEBEC TODAY. A STRONG COLD FRONT WILL MOVE
ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND LATE THIS AFTERNOON
INTO TONIGHT WITH RAIN SHOWERS TRANSITIONING TO SNOW SHOWERS.
BLUSTERY AND COLD CONDITIONS WILL OPEN THE WORK WEEK WITH LAKE
EFFECT SNOW SHOWERS MAINLY NORTH AND WEST OF THE GREATER CAPITAL
REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 534 AM EST...THE WINTER WX ADVISORY HAS BEEN CANCELED FOR
EASTERN ALBANY COUNTY. ALL OTHER ADVISORIES AND WARNINGS HAVE BEEN
KEPT UP UNTIL 6 AM AND 9 AM. THE PCPN HAVE BECOME SPOTTY THIS
HOUR...BUT ANOTHER BATCH IS ORGANIZING OVER CNTRL NY AHEAD OF THE
WARM FRONT. TEMPS HAVE BEEN STUBBORN TO RISE ABOVE FREEZING NORTH
AND EAST OF THE MID HUDSON VALLEY AND PORTIONS OF THE CAPITAL
DISTRICT. THE TREND WILL BE FOR THE TEMPS TO RISE ABOVE FREEZING
BTWN 6 AM AND 9 AM. ANY ADDITIONAL ICE ACCRETIONS WILL BE A
COATING TO A TENTH OF AN INCH WHERE THE ADVISORY IS STILL UP.
THE STRONG LLJ WITH THE SURGE OF GULF AND ATLANTIC MOISTURE IS NOW
LIFTING NORTH AND EAST OF THE REGION...AS LOW PRESSURE MOVES INTO
THE CNTRL-ERN GREAT LAKES REGION THIS MORNING. THE H850 WINDS ARE
SHIFTING TO THE SW FOR THE LATE MORNING INTO THE AFTERNOON. THE
WARM FRONT WILL TRY TO BREAK THROUGH MOST OF THE REGION WITH ONE
MORE SURGE OF WARM ADVECTION PCPN EXPECTED. THERE MAYBE ANOTHER
LULL IN THE PCPN IN THE LATE MORNING INTO THE AFTERNOON...AND THE
FCST AREA WILL BE IN A WARM SECTOR. EXPECT PLENTY OF CLOUDS TO BE
AROUND AND H850 TEMPS TO RISE TO +7C TO +10C. OUR MAX TEMPS
REFLECT THE METMOS VALUES WITH M40S TO L50S ACROSS THE REGION.
IT APPEARS A PREFRONTAL TROUGH WILL MOVE ACROSS THE REGION IN THE
LATE AFTERNOON AND THE COLD FRONT WILL APPROACH FOR THE EARLY
EVENING. THE LLJ AT H850 INCREASES TO 45-60 KTS AHEAD OF THE COLD
FRONT...AS THE SFC WAVE MOVES INTO SRN QUEBEC. THE CYCLONE DOES
DEEPEN TO CLOSE TO 990 HPA BY 00Z/MON. THE 6-HR PRESSURE FALLS ARE
EXPECTED TO BE OVER SE QUEBEC AND NRN NEW ENGLAND. THE H925 WINDS
AHEAD AND JUST BEHIND THE FRONT CONTINUE TO BE STRONG AT 30-40
KTS...BUT MIXING DOWN 40 KTS IN THE EARLY EVENING MAY BE
DIFFICULT. WE WILL CONTINUE TO HAVE SOME GUSTS TO 30 TO 40 WITH A
BURST OF SHOWERS WITH THE FRONT. EXPECT THE SHOWERS TO TRANSITION
TO SNOW SHOWERS ACROSS THE WRN DACKS IN THE EARLY EVENING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
LAKE EFFECT SNOW ADVISORY ISSUED FROM 7 PM SUNDAY TO 7 AM
MONDAY FOR NORTHERN HERKIMER AND HAMILTON COUNTIES...
LAKE EFFECT SNOW ADVISORY ISSUED FROM 4 AM MONDAY TO 7 PM
MONDAY FOR SOUTHERN HERKIMER...FULTON AND MONTGOMERY COUNTIES.
THE ADVISORIES ARE FOR SNOW AND BLOWING SNOW WITH GUSTY WINDS OF
35 TO 45 MPH.
OUR CONFIDENCE WAS NOT GREAT ENOUGH TO ISSUE A WIND ADVISORY FOR
PARTS OF THE REGION SUNDAY NIGHT...THOUGH A 3RD PERIOD ADVISORY
MAY BE NEEDED FOR MONDAY...AS BETTER MOMENTUM TRANSFER IS
EXPECTED...BUT FOR NOW WIDESPREAD 46-57 MPH WIND GUSTS ARE NOT
ANTICIPATED FOR SUNDAY NIGHT INTO MONDAY. THIS WILL CONTINUE TO BE
MONITORED.
TONIGHT...COLD FRONT MOVES ACROSS THE REGION WITH STRONG LOW LEVEL
COLD ADVECTION EXPECTED. WESTERLY UPSLOPE SNOW SHOWERS WILL
INITIALLY IMPACT THE WRN DACKS AND SRN GREENS MTNS WITH MORE SCT
RAIN AND SNOW SHOWER ACTIVITY AWAY FROM THESE AREAS.
THE LATEST HIRES WRF AND 3-KM HRRR INDICATE A TRANSITION FROM THE
WESTERLY UPSLOPE SNOW SHOWERS OVER THE WRN DACKS TO AN ORGANIZED
SINGLE BAND. BUFKIT PROFILES JUST DOWNSTREAM OF LAKE ONTARIO
INDICATED MODERATE INSTABILITY WITH AN INVERSION HEIGHT CLOSE TO
10 KFT. HOWEVER...THE BAND IS EXPECTED TO FORM AND QUICKLY
TRANSITION S/SE WITH THE STRONG VEERING WIND PROFILE IN THE
BOUNDARY LAYER. THE LOW LEVEL FLOW STARTS AT 260-270 DEGS AND THEN
SHIFTS TO A 280 TO 290 DEG LOW-LEVEL TRAJECTORY. A QUICK BLAST OF
HVY SNOW SHOWERS IS ANTICIPATED FOR THE WRN DACKS WITH 3 TO 6
INCHES OF SNOW WITH PERHAPS SOME 4 TO 8 INCH AMOUNTS JUST SOUTH OF
OLD FORGE AND INLET. THE TRANSITORY BAND MOVES INTO SRN HERKIMER
COUNTY...AND THE W-CNTRL MOHAWK VALLEY BTWN 4-7 AM. THE NAM AND
HIRES WRF SHOW A MULTI-LAKE CONNECTION WITH MDT INSTABILITY CLASS
AT KUCA BUFKIT PROFILE. THIS AREA MAY NEED AN UPGRADE LATER...BUT
WE PUT THE ENTIRE W-CNTRL MOHAWK VALLEY CORRIDOR WAS ALSO PLACED
IN A LAKE EFFECT SNOW ADVISORY FOR SNOW AND BLOWING SNOW. ADVISORY
WIND LEVEL GUSTS WILL BE CLOSE WITH 35 TO 45 MPH GUSTS FORECASTED.
LOWS WILL BE MUCH COLDER IN THE TEENS TO M20S WITH SOME SINGLE
DIGITS OVER THE ADIRONDACK PARK...AND U20S OVER THE MID HUDSON
VALLEY.
MONDAY...THE BETTER PRESSURE RISES PASS NORTH OF ST LAWRENCE RIVER
VALLEY AND NRN NY BTWN 12Z-18Z MON 8-10 HPA/6 HRS. THE ISALLOBARIC
COUPLET IS IMPRESSIVE AS THE CYCLONE DEEPENS AND INTENSIFIES TO
ABOUT 980 HPA OVER THE GULF OF ST LAWRENCE BY 12Z/MON. SOME
SUSTAINED WESTERLY WINDS OF 15 TO 25 MPH WITH GUSTS 35 TO 45 MPH
ARE EXPECTED. THE 10-M WINDS ON THE GFSMOS PRODUCT FOR KALB ARE
IMPRESSIVE IN THE 18-24 KT SUSTAINED RANGE. THE BUFKIT MOMENTUM
TRANSFER PROFILES SHOW 40 KTS WILL NEED TO MIXED FROM 2.5 KFT AGL
FOR WIND ADVISORY CRITERIA TO BE MET. ANY WIND FLAGS WILL BE
MONITORED BY LATER SHIFTS. IT DOES LOOK PLAUSIBLE THAT SOME LAKE
EFFECT SHOWERS MAY SNEAK DOWN THE MOHAWK RIVER VALLEY INTO THE
CAPITAL REGION AND NRN TACONICS. HIGH CHC AND LIKELY POPS WERE USED
LATE MONDAY MORNING INTO THE PM FOR A COATING TO PERHAPS A HALF AN
INCH OF SNOW. SOME OF THE UPSLOPE AREAS OF THE SRN GREENS IN THE
SRN VT...TACONICS...AND NRN BERKS COULD GET AN INCH OR TWO OR
SNOW. THE ADVISORY AREA HIGHLIGHTED WILL LIKELY RECEIVE 3 TO 6
INCHES WITH SOME ISOLATED 4 TO 8 INCH AMOUNTS. THE INVERSION
HEIGHTS DO LOWER IN THE AFTERNOON...AND THE SHEAR INCREASES SO THE
DOWNSTREAM TRAJECTORY WILL DECREASE. MAX TEMPS MAY BE IN THE
MORNING...AND TEMPS MAY CONTINUE TO FALL SLOWLY IN THE AFTERNOON
IN THE POTENT COLD ADVECTION REGIME...AS H850 TEMPS CRASH INTO THE
-17C TO -22C RANGE ACROSS THE FCST AREA. DAYTIME HIGHS WILL BE IN
THE M20S TO L30S FROM THE TRI CITIES SOUTH AND EAST...AND TEENS TO
L20S NORTH AND WEST WITH SOME SINGLE NUMBERS OVER THE SRN DACKS.
WIND CHILLS WILL RANGE FROM 10 BELOW TO 10 ABOVE ZERO.
MONDAY NIGHT...LAKE EFFECT SNOW BAND LIFTS BACK NORTHWARD...AS THE FLOW
BACKS WITH AN APPROACHING SHORT-WAVE/CLIPPER LOW FROM THE GREAT
LAKES REGION AND MIDWEST. HIGH PRESSURE BRIEFLY BUILDS IN FROM
QUEBEC WITH A VERY COLD NIGHT EXPECTED. THE WINDS SHOULD
DIMINISH...AND FRIGID TEMPS ARE ANTICIPATED WITH LOWS BELOW ZERO
OVER THE SRN DACKS...AND PARTS OF THE LAKE REGION REGION...AND
ZERO TO 10 ABOVE IN MOST OTHER LOCATIONS WITH SOME LOWER TEENS IN
THE CAPITAL DISTRICT AND MID HUDSON VALLEY.
CLOUDS WILL INCREASE IN THE FRIGID AIR MASS WITH THE BETTER CHANCE
FOR LIGHT SNOW AND SCT SNOW SHOWERS ON TUE.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
VERY COLD TEMPERATURES AND ACTIVE WEATHER THIS WEEK...WITH THE
COLDEST TEMPERATURES OF THE WINTER EXPECTED WEDNESDAY NIGHT AND
THURSDAY WITH LIFE-THREATENING WIND CHILLS POSSIBLE.
A QUICK MOVING NORTHERN STREAM CLIPPER SYSTEM WILL BRING A PERIOD OF
LIGHT SNOW TO THE AREA TUESDAY. THIS SYSTEM IS EXPECTED TO PASS OVER
THE OHIO VALLEY AND MOVE OFF THE DELMARVA. IT WILL HAVE LIMITED
MOISTURE BUT GOOD FORCING. LOOKING AT HIGH RATIO SNOWFALL. AT THIS
TIME EXPECT BELOW ADVISORY LEVEL ACCUMULATIONS. HIGHS WILL BE AROUND
10 DEGREES BELOW NORMAL.
THE NEXT QUICK MOVING LOW PRESSURE SYSTEM AND NORTHERN STREAM SHORT
WAVE WILL BE IN ITS HEELS. WILL HAVE CONTINUING CHANCES FOR SNOW
SHOWERS TUESDAY NIGHT WITH SOME LAKE EFFECT/ENHANCEMENT INTO THE
WESTERN ADIRONDACKS. EXPECT SNOW SHOWERS AND POSSIBLY SNOW SQUALLS
AS THE ARCTIC BOUNDARY APPROACHES AND MOVES THROUGH WEDNESDAY. THIS
SYSTEM/FRONT WILL BE THE ONE THAT OPENS THE DOOR TO THE ARCTIC
AIRMASS WITH ITS PASSAGE STRONG COLD AIR ADVECTION WILL BEGIN.
850 MB TEMPERATURES ARE MODELED TO DROP TO -25 TO -30 DEGREES
CELSIUS ACROSS THE FORECAST AREA WEDNESDAY NIGHT. SURFACE
TEMPERATURES ARE FORECAST TO PLUMMET RANGING FROM AROUND 1 DEGREES
TO AROUND 20 DEGREES BELOW ZERO...AROUND 20 DEGREES BELOW NORMAL. IN
ADDITION...THE PRESSURE GRADIENT ACROSS THE REGION WILL BE TIGHT
BETWEEN THE DEPARTING LOW PRESSURE SYSTEM AND AN ADVANCING HIGH
RESULTING IN BRISK AND GUSTY NORTHWEST WINDS. THE COMBINATION OF THE
BITTER TEMPERATURES AND BRISK WINDS WILL RESULT IN DANGEROUS TO
LIFE-THREATENING WIND CHILL VALUES WEDNESDAY NIGHT INTO THURSDAY
MORNING. WILL KEEP MENTION IN THE HAZARDOUS WEATHER OUTLOOK.
THURSDAY WILL BE A FRIGID DAY WITH SOME HIGHER PRESSURE BUILDING IN.
TEMPERATURES WILL REMAIN AROUND 20 DEGREES BELOW NORMAL. THE LAST
TIME IS WAS THIS COLD WAS BACK ON JANUARY 22 2014...THE HIGH
TEMPERATURE IN ALBANY WAS ONLY 9 DEGREES WITH A LOW OF 6 DEGREES
BELOW ZERO. LOOKING AT SIMILAR VALUES. WITH NORTHWEST FLOW ACROSS
THE GREAT LAKES WOULD EXPECT MULTI BANDS ACROSS CENTRAL NEW YORK
WHICH COULD MAY REACH INTO THE FAR WESTERN PORTION OF THE FORECAST
AREA.
YET ANOTHER NORTHERN STREAM SYSTEM WILL APPROACH LATE IN THE WEEK
BRINGING MORE CHANCES FOR SNOW SHOWERS TO THE AREA. TEMPERATURES
WILL MODERATE SOME IN THE SOUTHWEST FLOW AHEAD OF THE APPROACHING
SYSTEM HOWEVER THEY WILL REMAIN WELL BELOW NORMAL. THE COLDEST AIR
IS EXPECTED TO REMAIN TO OUR NORTH PASSING OVER EASTERN CANADA ITS
IN WAKE AS WE HEAD INTO THE WEEKEND. COULD BE LOOKING AT MORE LAKE
EFFECT IN THE WAKE OF THE SYSTEM.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
BOUNDARY LAYER STRUGGLES TO WARM. TEMPERATURES REMAIN JUST ABOVE
FREEZING AT KPOU AND KALB WITH 34 DEGREES. HOWEVER AT KPSF
TEMPERATURE HAS ONLY REACHED 32 DEGREES AND AT KGFL 30 DEGREES SO
FREEZING RAIN/FREEZING DRIZZLE CONTINUE TO BE A THREAT EARLY THIS
MORNING. THE STEADY PRECIPITATION MOVED OFF TO THE EAST EARLY THIS
MORNING HOWEVER REGIONAL RADARS TO OUR WEST INDICATE MORE ON THE WAY
AHEAD OF THE SURFACE LOW OVER THE OHIO VALLEY AND ITS ASSOCIATED
WARM FRONT WHICH IS CAUGHT UP IN THE APPALACHIANS. THE WARM FRONT
WILL BE FORCED ACROSS THE AREA THIS MORNING WITH THE SYSTEM`S COLD
FRONT SWEEPING THROUGH THIS AFTERNOON INTO THE EVENING AS THE
SURFACE LOW PASSES TO OUR NORTH.
IFR CONDITIONS WILL PERSIST AS A WARM FRONT APPROACHES. THE AREA
SHOULD BRIEFLY GET INTO THE WARM SECTOR OF THE LOW PRESSURE SYSTEM
WITH CHANCES FOR SHOWERS CONTINUING. CONDITIONS/CEILINGS WILL LIFT
WITH THE PASSAGE OF THE COLD FRONT.
WINDS WILL SHIFT TOWARD THE SOUTH WITH THE PASSAGE OF THE WARM FRONT
AND INCREASE IN SPEED. THEY WILL SHIFT TOWARD THE WEST WITH THE
PASSAGE OF THE COLD FRONT AND BECOME GUSTY. HAVE KEPT LOW LEVEL WIND
SHEAR IN KPOU TAF THROUGH MUCH OF THE DAY.
OUTLOOK...
MON NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUE: MODERATE OPERATIONAL IMPACT. LIKELY SN.
TUE NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
WED: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF SHSN.
WED NIGHT: LOW OPERATIONAL IMPACT. BREEZY.
THU: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
A COMPLEX STORM SYSTEM WITH MODERATE TO HEAVY QPF WILL MOVE ACROSS
THE HSA THROUGH TODAY.
MOST AREAS ARE FORECAST TO RECEIVE 1-2 INCHES OF LIQUID
EQUIVALENT PRECIPITATION...WITH LOCALLY IN EXCESS OF TWO INCHES.
THIS WILL ALLOW FOR SIGNIFICANT RISES ON RIVERS AND STREAMS ON
SUNDAY...AS TEMPERATURES RISE ABOVE FREEZING BRIEFLY OVER THE
ENTIRE REGION.
ISOLATED MINOR FLOODING IS POSSIBLE AND PER COLLABORATION
YESTERDAY WITH THE NERFC...THE HSA POINTS THAT GOES ABOVE ACTION
STAGE ARE WILLIAMSTOWN /WILM3/...AND GRANVILLE /GVVN6/ AT THIS
TIME. SINCE THE POTENTIAL OF WIDESPREAD MINOR FLOODING IS NOT
EXPECTED...A FLOOD WATCH HAS NOT BEEN ISSUED AT THIS TIME.
LAKE EFFECT SNOWFALL WILL IMPACT LOCATIONS NORTH AND WEST OF THE
CAPITAL REGION TONIGHT THROUGH MONDAY IN THE WAKE OF A STRONG COLD
FRONT.
THEREAFTER...BITTER COLD WEATHER IS EXPECTED NEXT WEEK. SOME
FREEZE UP ICE JAMS ARE POSSIBLE ACROSS THE SOUTHWESTERN
ADIRONDACKS AND SOUTHERN VERMONT BY LATE IN THE WEEK.
OTHERWISE...ICE WILL LIKELY DEVELOP AND INCREASE ACROSS RIVERS
AND STREAMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
CTZ001.
NY...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
NYZ032-038>040-048>050-053-054-084.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR NYZ033-
041>043-082-083.
LAKE EFFECT SNOW ADVISORY FROM 4 AM TO 7 PM EST MONDAY FOR
NYZ038>040-082.
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST
MONDAY FOR NYZ032-033.
MA...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
MAZ001-025.
VT...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
VTZ013.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR VTZ014-
015.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...IAA
AVIATION...IAA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
534 AM EST SUN JAN 4 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE FROM THE EASTERN GREAT LAKES
REGION TO SOUTHERN QUEBEC TODAY. A STRONG COLD FRONT WILL MOVE
ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND LATE THIS AFTERNOON
INTO TONIGHT WITH RAIN SHOWERS TRANSITIONING TO SNOW SHOWERS.
BLUSTERY AND COLD CONDITIONS WILL OPEN THE WORK WEEK WITH LAKE
EFFECT SNOW SHOWERS MAINLY NORTH AND WEST OF THE GREATER CAPITAL
REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 534 AM EST...THE WINTER WX ADVISORY HAS BEEN CANCELED FOR
EASTERN ALBANY COUNTY. ALL OTHER ADVISORIES AND WARNINGS HAVE BEEN
KEPT UP UNTIL 6 AM AND 9 AM. THE PCPN HAVE BECOME SPOTTY THIS
HOUR...BUT ANOTHER BATCH IS ORGANIZING OVER CNTRL NY AHEAD OF THE
WARM FRONT. TEMPS HAVE BEEN STUBBORN TO RISE ABOVE FREEZING NORTH
AND EAST OF THE MID HUDSON VALLEY AND PORTIONS OF THE CAPITAL
DISTRICT. THE TREND WILL BE FOR THE TEMPS TO RISE ABOVE FREEZING
BTWN 6 AM AND 9 AM. ANY ADDITIONAL ICE ACCRETIONS WILL BE A
COATING TO A TENTH OF AN INCH WHERE THE ADVISORY IS STILL UP.
THE STRONG LLJ WITH THE SURGE OF GULF AND ATLANTIC MOISTURE IS NOW
LIFTING NORTH AND EAST OF THE REGION...AS LOW PRESSURE MOVES INTO
THE CNTRL-ERN GREAT LAKES REGION THIS MORNING. THE H850 WINDS ARE
SHIFTING TO THE SW FOR THE LATE MORNING INTO THE AFTERNOON. THE
WARM FRONT WILL TRY TO BREAK THROUGH MOST OF THE REGION WITH ONE
MORE SURGE OF WARM ADVECTION PCPN EXPECTED. THERE MAYBE ANOTHER
LULL IN THE PCPN IN THE LATE MORNING INTO THE AFTERNOON...AND THE
FCST AREA WILL BE IN A WARM SECTOR. EXPECT PLENTY OF CLOUDS TO BE
AROUND AND H850 TEMPS TO RISE TO +7C TO +10C. OUR MAX TEMPS
REFLECT THE METMOS VALUES WITH M40S TO L50S ACROSS THE REGION.
IT APPEARS A PREFRONTAL TROUGH WILL MOVE ACROSS THE REGION IN THE
LATE AFTERNOON AND THE COLD FRONT WILL APPROACH FOR THE EARLY
EVENING. THE LLJ AT H850 INCREASES TO 45-60 KTS AHEAD OF THE COLD
FRONT...AS THE SFC WAVE MOVES INTO SRN QUEBEC. THE CYCLONE DOES
DEEPEN TO CLOSE TO 990 HPA BY 00Z/MON. THE 6-HR PRESSURE FALLS ARE
EXPECTED TO BE OVER SE QUEBEC AND NRN NEW ENGLAND. THE H925 WINDS
AHEAD AND JUST BEHIND THE FRONT CONTINUE TO BE STRONG AT 30-40
KTS...BUT MIXING DOWN 40 KTS IN THE EARLY EVENING MAY BE
DIFFICULT. WE WILL CONTINUE TO HAVE SOME GUSTS TO 30 TO 40 WITH A
BURST OF SHOWERS WITH THE FRONT. EXPECT THE SHOWERS TO TRANSITION
TO SNOW SHOWERS ACROSS THE WRN DACKS IN THE EARLY EVENING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
LAKE EFFECT SNOW ADVISORY ISSUED FROM 7 PM SUNDAY TO 7 AM
MONDAY FOR NORTHERN HERKIMER AND HAMILTON COUNTIES...
LAKE EFFECT SNOW ADVISORY ISSUED FROM 4 AM MONDAY TO 7 PM
MONDAY FOR SOUTHERN HERKIMER...FULTON AND MONTGOMERY COUNTIES.
THE ADVISORIES ARE FOR SNOW AND BLOWING SNOW WITH GUSTY WINDS OF
35 TO 45 MPH.
OUR CONFIDENCE WAS NOT GREAT ENOUGH TO ISSUE A WIND ADVISORY FOR
PARTS OF THE REGION SUNDAY NIGHT...THOUGH A 3RD PERIOD ADVISORY
MAY BE NEEDED FOR MONDAY...AS BETTER MOMENTUM TRANSFER IS
EXPECTED...BUT FOR NOW WIDESPREAD 46-57 MPH WIND GUSTS ARE NOT
ANTICIPATED FOR SUNDAY NIGHT INTO MONDAY. THIS WILL CONTINUE TO BE
MONITORED.
TONIGHT...COLD FRONT MOVES ACROSS THE REGION WITH STRONG LOW LEVEL
COLD ADVECTION EXPECTED. WESTERLY UPSLOPE SNOW SHOWERS WILL
INITIALLY IMPACT THE WRN DACKS AND SRN GREENS MTNS WITH MORE SCT
RAIN AND SNOW SHOWER ACTIVITY AWAY FROM THESE AREAS.
THE LATEST HIRES WRF AND 3-KM HRRR INDICATE A TRANSITION FROM THE
WESTERLY UPSLOPE SNOW SHOWERS OVER THE WRN DACKS TO AN ORGANIZED
SINGLE BAND. BUFKIT PROFILES JUST DOWNSTREAM OF LAKE ONTARIO
INDICATED MODERATE INSTABILITY WITH AN INVERSION HEIGHT CLOSE TO
10 KFT. HOWEVER...THE BAND IS EXPECTED TO FORM AND QUICKLY
TRANSITION S/SE WITH THE STRONG VEERING WIND PROFILE IN THE
BOUNDARY LAYER. THE LOW LEVEL FLOW STARTS AT 260-270 DEGS AND THEN
SHIFTS TO A 280 TO 290 DEG LOW-LEVEL TRAJECTORY. A QUICK BLAST OF
HVY SNOW SHOWERS IS ANTICIPATED FOR THE WRN DACKS WITH 3 TO 6
INCHES OF SNOW WITH PERHAPS SOME 4 TO 8 INCH AMOUNTS JUST SOUTH OF
OLD FORGE AND INLET. THE TRANSITORY BAND MOVES INTO SRN HERKIMER
COUNTY...AND THE W-CNTRL MOHAWK VALLEY BTWN 4-7 AM. THE NAM AND
HIRES WRF SHOW A MULTI-LAKE CONNECTION WITH MDT INSTABILITY CLASS
AT KUCA BUFKIT PROFILE. THIS AREA MAY NEED AN UPGRADE LATER...BUT
WE PUT THE ENTIRE W-CNTRL MOHAWK VALLEY CORRIDOR WAS ALSO PLACED
IN A LAKE EFFECT SNOW ADVISORY FOR SNOW AND BLOWING SNOW. ADVISORY
WIND LEVEL GUSTS WILL BE CLOSE WITH 35 TO 45 MPH GUSTS FORECASTED.
LOWS WILL BE MUCH COLDER IN THE TEENS TO M20S WITH SOME SINGLE
DIGITS OVER THE ADIRONDACK PARK...AND U20S OVER THE MID HUDSON
VALLEY.
MONDAY...THE BETTER PRESSURE RISES PASS NORTH OF ST LAWRENCE RIVER
VALLEY AND NRN NY BTWN 12Z-18Z MON 8-10 HPA/6 HRS. THE ISALLOBARIC
COUPLET IS IMPRESSIVE AS THE CYCLONE DEEPENS AND INTENSIFIES TO
ABOUT 980 HPA OVER THE GULF OF ST LAWRENCE BY 12Z/MON. SOME
SUSTAINED WESTERLY WINDS OF 15 TO 25 MPH WITH GUSTS 35 TO 45 MPH
ARE EXPECTED. THE 10-M WINDS ON THE GFSMOS PRODUCT FOR KALB ARE
IMPRESSIVE IN THE 18-24 KT SUSTAINED RANGE. THE BUFKIT MOMENTUM
TRANSFER PROFILES SHOW 40 KTS WILL NEED TO MIXED FROM 2.5 KFT AGL
FOR WIND ADVISORY CRITERIA TO BE MET. ANY WIND FLAGS WILL BE
MONITORED BY LATER SHIFTS. IT DOES LOOK PLAUSIBLE THAT SOME LAKE
EFFECT SHOWERS MAY SNEAK DOWN THE MOHAWK RIVER VALLEY INTO THE
CAPITAL REGION AND NRN TACONICS. HIGH CHC AND LIKELY POPS WERE USED
LATE MONDAY MORNING INTO THE PM FOR A COATING TO PERHAPS A HALF AN
INCH OF SNOW. SOME OF THE UPSLOPE AREAS OF THE SRN GREENS IN THE
SRN VT...TACONICS...AND NRN BERKS COULD GET AN INCH OR TWO OR
SNOW. THE ADVISORY AREA HIGHLIGHTED WILL LIKELY RECEIVE 3 TO 6
INCHES WITH SOME ISOLATED 4 TO 8 INCH AMOUNTS. THE INVERSION
HEIGHTS DO LOWER IN THE AFTERNOON...AND THE SHEAR INCREASES SO THE
DOWNSTREAM TRAJECTORY WILL DECREASE. MAX TEMPS MAY BE IN THE
MORNING...AND TEMPS MAY CONTINUE TO FALL SLOWLY IN THE AFTERNOON
IN THE POTENT COLD ADVECTION REGIME...AS H850 TEMPS CRASH INTO THE
-17C TO -22C RANGE ACROSS THE FCST AREA. DAYTIME HIGHS WILL BE IN
THE M20S TO L30S FROM THE TRI CITIES SOUTH AND EAST...AND TEENS TO
L20S NORTH AND WEST WITH SOME SINGLE NUMBERS OVER THE SRN DACKS.
WIND CHILLS WILL RANGE FROM 10 BELOW TO 10 ABOVE ZERO.
MONDAY NIGHT...LAKE EFFECT SNOW BAND LIFTS BACK NORTHWARD...AS THE FLOW
BACKS WITH AN APPROACHING SHORT-WAVE/CLIPPER LOW FROM THE GREAT
LAKES REGION AND MIDWEST. HIGH PRESSURE BRIEFLY BUILDS IN FROM
QUEBEC WITH A VERY COLD NIGHT EXPECTED. THE WINDS SHOULD
DIMINISH...AND FRIGID TEMPS ARE ANTICIPATED WITH LOWS BELOW ZERO
OVER THE SRN DACKS...AND PARTS OF THE LAKE REGION REGION...AND
ZERO TO 10 ABOVE IN MOST OTHER LOCATIONS WITH SOME LOWER TEENS IN
THE CAPITAL DISTRICT AND MID HUDSON VALLEY.
CLOUDS WILL INCREASE IN THE FRIGID AIR MASS WITH THE BETTER CHANCE
FOR LIGHT SNOW AND SCT SNOW SHOWERS ON TUE.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
VERY COLD TEMPERATURES AND ACTIVE WEATHER THIS WEEK...WITH THE
COLDEST TEMPERATURES OF THE WINTER EXPECTED WEDNESDAY NIGHT AND
THURSDAY WITH LIFE-THREATENING WIND CHILLS POSSIBLE.
A QUICK MOVING NORTHERN STREAM CLIPPER SYSTEM WILL BRING A PERIOD OF
LIGHT SNOW TO THE AREA TUESDAY. THIS SYSTEM IS EXPECTED TO PASS OVER
THE OHIO VALLEY AND MOVE OFF THE DELMARVA. IT WILL HAVE LIMITED
MOISTURE BUT GOOD FORCING. LOOKING AT HIGH RATIO SNOWFALL. AT THIS
TIME EXPECT BELOW ADVISORY LEVEL ACCUMULATIONS. HIGHS WILL BE AROUND
10 DEGREES BELOW NORMAL.
THE NEXT QUICK MOVING LOW PRESSURE SYSTEM AND NORTHERN STREAM SHORT
WAVE WILL BE IN ITS HEELS. WILL HAVE CONTINUING CHANCES FOR SNOW
SHOWERS TUESDAY NIGHT WITH SOME LAKE EFFECT/ENHANCEMENT INTO THE
WESTERN ADIRONDACKS. EXPECT SNOW SHOWERS AND POSSIBLY SNOW SQUALLS
AS THE ARCTIC BOUNDARY APPROACHES AND MOVES THROUGH WEDNESDAY. THIS
SYSTEM/FRONT WILL BE THE ONE THAT OPENS THE DOOR TO THE ARCTIC
AIRMASS WITH ITS PASSAGE STRONG COLD AIR ADVECTION WILL BEGIN.
850 MB TEMPERATURES ARE MODELED TO DROP TO -25 TO -30 DEGREES
CELSIUS ACROSS THE FORECAST AREA WEDNESDAY NIGHT. SURFACE
TEMPERATURES ARE FORECAST TO PLUMMET RANGING FROM AROUND 1 DEGREES
TO AROUND 20 DEGREES BELOW ZERO...AROUND 20 DEGREES BELOW NORMAL. IN
ADDITION...THE PRESSURE GRADIENT ACROSS THE REGION WILL BE TIGHT
BETWEEN THE DEPARTING LOW PRESSURE SYSTEM AND AN ADVANCING HIGH
RESULTING IN BRISK AND GUSTY NORTHWEST WINDS. THE COMBINATION OF THE
BITTER TEMPERATURES AND BRISK WINDS WILL RESULT IN DANGEROUS TO
LIFE-THREATENING WIND CHILL VALUES WEDNESDAY NIGHT INTO THURSDAY
MORNING. WILL KEEP MENTION IN THE HAZARDOUS WEATHER OUTLOOK.
THURSDAY WILL BE A FRIGID DAY WITH SOME HIGHER PRESSURE BUILDING IN.
TEMPERATURES WILL REMAIN AROUND 20 DEGREES BELOW NORMAL. THE LAST
TIME IS WAS THIS COLD WAS BACK ON JANUARY 22 2014...THE HIGH
TEMPERATURE IN ALBANY WAS ONLY 9 DEGREES WITH A LOW OF 6 DEGREES
BELOW ZERO. LOOKING AT SIMILAR VALUES. WITH NORTHWEST FLOW ACROSS
THE GREAT LAKES WOULD EXPECT MULTI BANDS ACROSS CENTRAL NEW YORK
WHICH COULD MAY REACH INTO THE FAR WESTERN PORTION OF THE FORECAST
AREA.
YET ANOTHER NORTHERN STREAM SYSTEM WILL APPROACH LATE IN THE WEEK
BRINGING MORE CHANCES FOR SNOW SHOWERS TO THE AREA. TEMPERATURES
WILL MODERATE SOME IN THE SOUTHWEST FLOW AHEAD OF THE APPROACHING
SYSTEM HOWEVER THEY WILL REMAIN WELL BELOW NORMAL. THE COLDEST AIR
IS EXPECTED TO REMAIN TO OUR NORTH PASSING OVER EASTERN CANADA ITS
IN WAKE AS WE HEAD INTO THE WEEKEND. COULD BE LOOKING AT MORE LAKE
EFFECT IN THE WAKE OF THE SYSTEM.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
BOUNDARY LAYER STRUGGLES TO WARM. TEMPERATURES REMAIN JUST ABOVE
FREEZING AT KPOU AND KALB WITH 34 DEGREES. HOWEVER AT KPSF
TEMPERATURE HAS ONLY REACHED 32 DEGREES AND AT KGFL 30 DEGREES SO
FREEZING RAIN/FREEZING DRIZZLE CONTINUE TO BE A THREAT EARLY THIS
MORNING. THE STEADY PRECIPITATION MOVED OFF TO THE EAST EARLY THIS
MORNING HOWEVER REGIONAL RADARS TO OUR WEST INDICATE MORE ON THE WAY
AHEAD OF THE SURFACE LOW OVER THE OHIO VALLEY AND ITS ASSOCIATED
WARM FRONT WHICH IS CAUGHT UP IN THE APPALACHIANS. THE WARM FRONT
WILL BE FORCED ACROSS THE AREA THIS MORNING WITH THE SYSTEM`S COLD
FRONT SWEEPING THROUGH THIS AFTERNOON INTO THE EVENING AS THE
SURFACE LOW PASSES TO OUR NORTH.
IFR CONDITIONS WILL PERSIST AS A WARM FRONT APPROACHES. THE AREA
SHOULD BRIEFLY GET INTO THE WARM SECTOR OF THE LOW PRESSURE SYSTEM
WITH CHANCES FOR SHOWERS CONTINUING. CONDITIONS/CEILINGS WILL LIFT
WITH THE PASSAGE OF THE COLD FRONT.
WINDS WILL SHIFT TOWARD THE SOUTH WITH THE PASSAGE OF THE WARM FRONT
AND INCREASE IN SPEED. THEY WILL SHIFT TOWARD THE WEST WITH THE
PASSAGE OF THE COLD FRONT AND BECOME GUSTY. HAVE KEPT LOW LEVEL WIND
SHEAR IN KPOU TAF THROUGH MUCH OF THE DAY.
OUTLOOK...
MON NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUE: MODERATE OPERATIONAL IMPACT. LIKELY SN.
TUE NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
WED: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF SHSN.
WED NIGHT: LOW OPERATIONAL IMPACT. BREEZY.
THU: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
A COMPLEX STORM SYSTEM WITH MODERATE TO HEAVY QPF WILL MOVE ACROSS
THE HSA THROUGH TODAY.
MOST AREAS ARE FORECAST TO RECEIVE 1-2 INCHES OF LIQUID
EQUIVALENT PRECIPITATION...WITH LOCALLY IN EXCESS OF TWO INCHES.
THIS WILL ALLOW FOR SIGNIFICANT RISES ON RIVERS AND STREAMS ON
SUNDAY...AS TEMPERATURES RISE ABOVE FREEZING BRIEFLY OVER THE
ENTIRE REGION.
ISOLATED MINOR FLOODING IS POSSIBLE AND PER COLLABORATION
YESTERDAY WITH THE NERFC...THE HSA POINTS THAT GOES ABOVE ACTION
STAGE ARE WILLIAMSTOWN /WILM3/...AND GRANVILLE /GVVN6/ AT THIS
TIME. SINCE THE POTENTIAL OF WIDESPREAD MINOR FLOODING IS NOT
EXPECTED...A FLOOD WATCH HAS NOT BEEN ISSUED AT THIS TIME.
LAKE EFFECT SNOWFALL WILL IMPACT LOCATIONS NORTH AND WEST OF THE
CAPITAL REGION TONIGHT THROUGH MONDAY IN THE WAKE OF A STRONG COLD
FRONT.
THEREAFTER...BITTER COLD WEATHER IS EXPECTED NEXT WEEK. SOME
FREEZE UP ICE JAMS ARE POSSIBLE ACROSS THE SOUTHWESTERN
ADIRONDACKS AND SOUTHERN VERMONT BY LATE IN THE WEEK.
OTHERWISE...ICE WILL LIKELY DEVELOP AND INCREASE ACROSS RIVERS
AND STREAMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
CTZ001.
NY...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
NYZ032-038>040-048>050-053-054-084.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR NYZ033-
041>043-082-083.
LAKE EFFECT SNOW ADVISORY FROM 4 AM TO 7 PM EST MONDAY FOR
NYZ038>040-082.
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST
MONDAY FOR NYZ032-033.
MA...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
MAZ001-025.
VT...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
VTZ013.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR VTZ014-
015.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...IAA
AVIATION...WASULA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
730 AM EST SUN JAN 4 2015
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE WEST TONIGHT AND PUSH THROUGH
LATE SUNDAY FOLLOWED BY DRY HIGH PRESSURE. A STRONGER COLD FRONT
WILL DROP THROUGH WEDNESDAY EVENING...THEN COLD HIGH PRESSURE WILL
BUILD OVER THE REGION INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
NEARING DAWN...SHOWERS HAVE MAINLY ENDED ALONG UPPER REACHES OF CHARLESTON
AND BERKELEY COUNTIES WITH WIDESPREAD LOW CLOUDS ACROSS MUCH OF THE
FORECAST AREA. VERY LITTLE IN THE WAY OF FOG OVER LAND AREAS AS
LOW LEVEL WINDS WERE JUST TOO STRONG. OCCASIONAL SEA FOG WAS BRUSHING
THE BEACHES AND BARRIER ISLANDS BUT NOT EXTENSIVE ENOUGH TO WARRANT
ANY DENSE FOG ADVISORIES. TEMPS AND DEW POINTS IN THE MID TO UPPER
60S IN THE WARM SECTOR.
AN AXIS OF VORTICITY AND LOW-LEVEL CONVERGENCE COULD CONTINUE TO
SUPPORT SPORADIC LIGHT SHOWERS ESPECIALLY OVER NORTHERN COASTAL COUNTIES
INTO THE MID/LATE MORNING. HOWEVER...THE MAIN PRECIPITATION EVENT
WILL ARRIVE THIS AFTERNOON AN INCREASINGLY ELONGATED/POSITIVELY
TILTED UPPER SHORTWAVE TROUGH EMBEDDED WITHIN A FAST WESTERLY FLOW
WILL DRIVE A SURFACE COLD FRONT INTO THE SOUTHEAST LATER THIS
AFTERNOON AND EVENING. AHEAD OF THE FRONT...STRONG LOW-LEVEL WINDS
WILL MAINTAIN AN UNSEASONABLY STRONG WARM SECTOR INTO THE REGION...MARKED
BY TEMPERATURES IN THE UPPER 70S AND DEWPOINTS IN THE MID/UPPER 60S.
SOME AREAS COULD REACH 80 DEGREES THIS AFTERNOON IS WE SEE BREAKS
FOR A WHILE. FORECAST THINKING FROM LATEST MODEL ANALYSIS HAS NOT
CHANGED MUCH IN TIMING THE ADVANCING PRE-FRONTAL CONVECTIVE RAINS
THIS AFTERNOON. STRONG TROPOSPHERIC WINDS COULD SUPPORT QUASI-
LINEAR CONVECTION INCLUDING BOWING SEGMENTS AND STRONG/ISOLATED
DAMAGING WIND GUSTS. HOWEVER...LIMITED LOW LEVEL INSTABILITY AND
POOR MID LEVEL LAPSE RATES WILL LIKELY PRECLUDE A SIGNIFICANT
SEVERE WEATHER EVENT. HOWEVER...ISOLATED SEVERE WEATHER IS
CERTAINLY POSSIBLE THIS AFTERNOON AND THE LOCATION THAT CAUGHT OUR
FORECAST INTEREST EARLY THIS MORNING WAS ACROSS PARTS OF SE
GEORGIA. THE LATEST OPERATIONAL RAP INDICATES POTENTIAL FOR
MUCAPES AND SBCAPES TO APPROACH 1000 J/KG TO THE SOUTH OF I-16 BY
MID AFTERNOON. THIS BUOYANCY WHILE LIMITED BY A POOR 500 MB-700 MB
LAYER DOES OFFER SOME DRY AIR ALOFT AND A POTENTIAL FOR SOME
ENHANCED CONVECTIVE WIND GUSTS. THE 00Z NSSL WRF MODEL PAINTS THE
HIGHEST FORECAST REFLECTIVITIES WITH BETTER LINEAR CONVECTIVE
ORGANIZATION DOWN IN THIS REGION AS WELL.
IF TEMPS WARM A LITTLE MORE THAN EXPECTED ALONG THE CHARLESTON COASTAL
CORRIDOR LATER THIS AFTERNOON...GUSTY WINDS OVER 35 MPH ARE POSSIBLE
ON AREA BRIDGES BUT THIS IS UNCERTAIN AT THIS POINT.
LAKE WINDS...WITHIN THE WARM SECTOR THE POTENTIAL FOR 25 KNOT
SOUTH/SOUTHWEST WIND GUSTS APPEARS SUFFICIENT TO JUSTIFY MAINTAINING
THE LAKE WIND ADVISORY ALONG LAKE SHORES FOR LAKE MOULTRIE VALID
10 AM UNTIL 5 PM TODAY.
THE COLD FRONT WILL SHIFT OFFSHORE BY MIDNIGHT TONIGHT...FOLLOWED
BY WEAK BUT DRY HIGH PRESSURE THROUGH TUESDAY. BY DAYBREAK MONDAY...
COLD ADVECTION WILL PUSH TEMPERATURES INTO THE 40S AT MOST LOCATIONS.
CLOUDS WILL BEGIN TO SCATTER OUT FROM THE WEST LATER TONIGHT.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
THE UPPER LEVEL PATTERN BECOMES ZONAL MONDAY THROUGH WEDNESDAY. DRY
HIGH PRESSURE WILL SPREAD INTO THE SOUTHEAST UNITED STATES ON MONDAY
THOUGH MODEST WNW FLOW AROUND 850 MB WILL SUPPORT DOWNSLOPE WARMING
AND HIGHS NEAR 60.
THE SURFACE HIGH WILL SHIFT OFF THE MID-ATLANTIC COAST MONDAY NIGHT
WITH A BRIEF RETURN FLOW AND INCREASING WSW LOW-LEVEL WINDS. WARM
AIR ADVECTION ON TUESDAY AND MOSTLY SUNNY SKIES WILL ALLOW TEMPS TO
REBOUND INTO THE MIDDLE 60S.
BOUNDARY LAYER FLOW VEERS AROUND TO THE NW LATE TUESDAY NIGHT INTO
WEDNESDAY...THOUGH 20-25 KT OF WNW 850 MB FLOW WILL MAINTAIN SOME
ADIABATIC WARMING. WEDNESDAY HIGH TEMPS WILL BE IN THE MID/UPPER 50S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
A DIGGING LONGWAVE TROUGH SHIFTS THROUGH THE AREA WEDNESDAY NIGHT
AND THURSDAY WITH A STRONG COLD FRONT DROPPING THROUGH THE AREA
WEDNESDAY EVENING. IMPRESSIVE COLD AIR ADVECTION WILL ENSUE AS A
VERY DRY HIGH PRESSURE AIRMASS DROPS SOUTHEAST. THE ECMWF HAS
GENERALLY BEEN THE COLDER OF THE MODELS WITH THIS SYSTEM...THOUGH IT
HAS MODERATED SOMEWHAT IN RECENT RUNS. NEVERTHELESS...A COLD 36 HRS
IS IN STORE. THURSDAY MORNING WILL LIKELY DROP INTO THE LOWER TO
MIDDLE 20S...COINCIDENT WITH 15-20 KT WINDS. OUR LATEST APPARENT
TEMPERATURE GRIDS SHOW THE POTENTIAL FOR WIND CHILL ADVISORY
CRITERIA FOR A FEW HOURS LATE WEDNESDAY NIGHT. IT IS WORTH NOTING
THAT OUR CRITERIA FOR ISSUING WIND CHILL ADVISORIES INCREASED ON
DECEMBER 1ST 2014. THE NEW CRITERIA IS 15 DEGREES IN COASTAL
LOCATIONS OR 10 DEGREES INLAND. WE WILL ADD MENTION TO THE HAZARDOUS
WEATHER OUTLOOK.
STRONG COLD ADVECTION CONTINUING ON THURSDAY WILL YIELD BLUSTERY
CONDITIONS. BASED ON THE LATEST THICKNESS PROGS WE LOWERED HIGHS TO
THE UPPER 30S NORTH TO LOWER 40S SOUTH. THURSDAY NIGHT WILL AGAIN BE
COLD AS HIGH PRESSURE REMAINS TO THE WEST. THERE WERE EARLIER
INDICATIONS THAT THE BOUNDARY LAYER COULD DECOUPLE AND ALLOW FOR LOW
TEMPS IN THE TEENS. MORE RECENT MODEL RUNS SHOW A WEAK SHORTWAVE
MOVING THROUGH OVERNIGHT WITH STRENGTHENING 850 MB WINDS PREVENTING
SURFACE WINDS FROM GOING CALM. WE MAINTAINED LOW TEMPS IN THE LOW TO
MID 20S.
THE UPPER LEVEL PATTERN TRANSITIONS TO A BROAD TROUGH ACROSS THE
CENTRAL UNITED STATES FRIDAY INTO THE WEEKEND WITH THE SURFACE HIGH
EVENTUALLY MOVING INTO THE NORTHEAST STATES. MOISTURE WILL BEGIN TO
INCREASE LATE IN THE WEEKEND WITH INCREASING CLOUDS AND POSSIBLE
RAIN SHOWERS SATURDAY NIGHT AND SUNDAY. TEMPS WILL REMAIN BELOW
NORMAL BUT HIGHS WILL GENERALLY BE IN THE 50S.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
EXTENSIVE IFR CIGS THROUGH THE COASTAL CORRIDOR AT 12Z WITH LOW LEVEL
WINDS RUNNING TOO STRONG TO BE A CONCERN FOR FOG/REDUCED VSBYS.
LATEST FORECAST SOUNDINGS SUGGEST IFR CIGS WILL HANG IN THROUGH
MUCH OF THIS MORNING AND THEN LIFT TO MVFR BY EARLY AFTERNOON BEFORE
A BIT OF A BREAK OUT PRIOR TO BANDS OF CONVECTIVE RAINS REACH THE
TERMINALS AFTER MID AFTERNOON. SURFACE WINDS WILL BE GUSTY AHEAD
OF THE RAINS WITH GUSTS TOPPING 25 KT AT KCHS AND 20 KT AT KSAV.
THE COLD FRONT WILL MOVE OFF THE COAST THIS EVENING WITH CONDITIONS
FAVORING VFR TONIGHT IN THE WAKE OF THE FRONT.
EXTENDED AVIATION OUTLOOK...VFR.
&&
.MARINE...
DENSE SEA FOG DIFFICULT TO SCOUR OUT OVER THE COOLEST SHELF WATERS
AND MAY BE AROUND FOR MUCH OF THE MORNING AND PERHAPS INTO THE
AFTERNOON OR EARLY EVENING HOURS. WE HAVE MARINE FOG ADVISORIES
OVER NEAR SHORE WATERS AND THE HARBOR THIS MORNING...EXTENSIONS
ARE POSSIBLE INTO THE AFTERNOON.
THE COOL STABLE NEAR SHORE WATERS TYPIFIED BY THE 5-7 KT OF WIND
OVERNIGHT AT GRAYS REEF WHILE TEMPS REACHING THE MID 60S ALONG
THE GEORGIA COAST SUPPORTIVE OF 15 KT WINDS WITH THE STRONGEST FLOW
RELEGATED TO WARMER WATERS OFFSHORE. THE SMALL CRAFT ADVISORIES IN
OUR NEAR SHORE WATERS WILL BE MARGINAL TODAY ONCE YOU GET AWAY
FROM THE LAND/SEA INTERFACE BUT WE MAINTAINED 4-6 FT SEAS TO
KEEP PERSISTENCE. THE HIGHEST SEAS IN NEAR SHORE LEGS SHOULD OCCUR
ACROSS THE NORTHEAST PART OF AMZ350. THE CHARLESTON HARBOR WILL
BE GUSTY AT TIMES TODAY...ESPECIALLY THE UPPER REACHES WHERE THE
WARMER SURFACE TEMPS OCCUR. THE FRONT WILL MOVE OFFSHORE LATER
TONIGHT WITH SOME JETTING OF THE W AND NW FLOW OFF THE GEORGIA
COAST. WE BUMPED UP WINDS A BIT FROM GRAYS REEF SEAWARD TO TREND.
WINDS/SEAS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA MONDAY
THROUGH WEDNESDAY. CONDITIONS QUICKLY DETERIORATE WEDNESDAY EVENING
BEHIND A STRONG COLD FRONT. STRONG LOW-LEVEL WINDS AND COLD AIR
ADVECTION WILL YIELD WINDS TURNING AROUND TO THE NORTH AND
INCREASING TO 25-30 KT. FREQUENT 35 KT GUSTS ARE INCREASINGLY
LIKELY WEDNESDAY NIGHT INTO THURSDAY MORNING ACROSS THE WARMER
WATERS BEYOND ABOUT 15 NM FROM SHORE. A PERIOD OF GALE
WATCHES/WARNINGS IS LIKELY FOR PORTIONS OF THE WATERS DURING THIS
TIME.
CONDITIONS QUICKLY IMPROVE LATER THURSDAY INTO THE WEEKEND AS THE
HIGH PRESSURE SYSTEM WEAKENS AND EVENTUALLY SHIFTS NORTHEAST.
&&
.CLIMATE...
RECORD HIGH TEMPERATURES JAN 4...
CHS 77/2005 AND PREVIOUS...
CXM 75/1955...
SAV 80/2004...
RECORD HIGH MINIMUM TEMPERATURES JAN 4...
CHS 58/1950 AND PREVIOUS...
CXM 61/2007...
SAV 60/2004 AND PREVIOUS...
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...LAKE WIND ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR SCZ045.
MARINE...DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR AMZ330-350-
352-354.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR AMZ352.
SMALL CRAFT ADVISORY UNTIL 5 AM EST MONDAY FOR AMZ350.
SMALL CRAFT ADVISORY UNTIL 11 AM EST MONDAY FOR AMZ374.
SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR AMZ330.
&&
$$
NEAR TERM...
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...JRL
CLIMATE...
AREA FORECAST DISCUSSION
NWS JACKSON KY
937 AM EST SUN JAN 4 2015
.UPDATE...
ISSUED AT 936 AM EST SUN JAN 4 2015
UPDATED POPS TO REFLECT THE CURRENT PLACEMENT OF A LINE OF SHOWERS
JUST ALONG AND AHEAD OF THE COLD FRONT WHICH IS TRAVERSING EASTERN
KY. EXPECT THE FRONT...AS WELL AS THE LINE OF SHOWERS...TO BE EAST OF
THE REGION IN THE NEXT COUPLE OF HOURS. ENDED UP SPEEDING UP THE
ONGOING FORECAST BY AN HOUR TO BETTER DEPICT THIS MOVEMENT. ALSO
LOADED IN THE LATEST OBSERVATIONAL DATA FOR TEMPS...DEW POINTS...AND
WINDS...INTO THE NEAR TERM FORECAST TO MAKE SURE EACH OF THESE
PARAMETERS WAS WELL REFLECTED OVER THE NEXT FEW HOURS.
UPDATE ISSUED AT 730 AM EST SUN JAN 4 2015
THE COLD FRONT IS NOW ENTERING EAST KENTUCKY BRINGING A NARROW BAND
OF MODERATE RAINS AND GUSTY WINDS OF BETWEEN 30 AND 40 MPH. HAVE
TIMED THIS THROUGH THE CWA IN THE GRIDS. TEMPERATURES WILL BE A
CHALLENGE OVER THE NEXT COUPLE OF HOURS WITH MOST PLACES
EXPERIENCING THEIR HIGH TEMPERATURE FOR THE DAY ATTM WITH FALLING
TEMPERATURES TO FOLLOW THROUGH THE MORNING AND INTO THE AFTERNOON.
DID UPDATE THE TEMPS AND DEWPOINTS FOR THE NEXT FEW HOURS BASED ON
THE FRONT AND THE CURRENT READINGS. THESE FRESHENED GRIDS HAVE BEEN
SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 320 AM EST SUN JAN 4 2015
07Z SFC ANALYSIS SHOWS A DEEPENING AREA OF LOW PRESSURE MOVING INTO
THE OHIO VALLEY. THIS LOW IS DRAGGING A COLD FRONT THROUGH KENTUCKY
TRAILING A BAND OF STEADY LIGHT TO MODERATE RAIN SHOWERS PASSING
THROUGH EASTERN KENTUCKY. THE HEAVIER SHOWERS HAVE SETTLED DOWN AND
MOVED OFF TO THE EAST WHILE MORE SCATTERED SHOWERS ARE FOUND OVER
CENTRAL KENTUCKY ALONG AND JUST AHEAD OF THE COLD FRONT. EAST
KENTUCKY IS ENJOYING A VERY MILD EARLY JANUARY NIGHT AHEAD OF THE
COLD FRONT WITH TEMPERATURES IN THE MID AND UPPER 50S WHILE DEWPOINTS
ARE NOT MUCH LOWER. WINDS HAVE BEEN RATHER LIGHT FROM THE SOUTH
THROUGH THE AREA DESPITE THE TIGHTENING PRESSURE GRADIENT AND WINDS
ROARING JUST OFF THE SFC...AS SEEN IN THE JKL VWP.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM AS WE
ENTER A PERIOD OF SHARP WX TRANSITION. A FAIRLY DEEP FULL LATITUDE
TROUGH WILL SWEEP INTO THE OHIO VALLEY TODAY WITH ITS CORE BATCH OF
ENERGY PASSING THROUGH EAST KENTUCKY BY 00Z. VERY FAST FLOW THROUGH
THE BASE OF THE LARGE...BUT NOT SETTLING TOO FAR SOUTH...TROUGH THEN
WILL KEEP MINOR WAVES MOVING PAST ALOFT TONIGHT AND THROUGH THE DAY
MONDAY. GIVEN THE CLOSE MODEL AGREEMENT HERE WILL CONTINUE TO FAVOR A
BLEND OF THE HRRR AND NAM12 TODAY FOLLOWED BY THE ECMWF AND NAM12 FOR
TONIGHT AND MONDAY.
SENSIBLE WEATHER WILL FEATURE THE WARMEST TEMPERATURES OF THE
FORECAST EARLY THIS MORNING AHEAD OF THE COLD FRONT. THIS BOUNDARY
WILL GO THROUGH BY MID MORNING...THOUGH...AND START US ON OUR DESCENT
TO SINGLE DIGIT TEMPS THAT WILL BE IN HERE BY THURSDAY MORNING. THE
RAIN ASSOCIATED WITH THE COLD FRONT THIS MORNING WILL COME TO AN END
WITH ITS PASSAGE...THOUGH THAT SHORTWAVE CROSSING OVERHEAD THIS
AFTERNOON AND A COMBINATION OF WRAP AROUND AND UPSLOPE FLOW WILL
LIKELY LEAD TO A REDEVELOPMENT OF LIGHT PCPN MOVING IN FROM THE
NORTHWEST BY LATE AFTERNOON. AS TEMPERATURES COOL INTO THE EVENING
EXPECT THE LINGERING LIGHT SHOWERS TO TRANSITION TO SNOW SHOWERS FOR
A BRIEF TIME. THESE WILL BE A BIT MORE ROBUST IN THE HIGHER TERRAIN
NEAR THE VIRGINIA BORDER POTENTIALLY RESULTING IN A DUSTING OF
ACCUMULATION BY EARLY MONDAY MORNING. DRIER AIR AND ARRIVING HIGH
PRESSURE WILL PUT AN END TO ANY LEFTOVER FLURRIES MONDAY MORNING...
THOUGH TEMPERATURES WILL STRUGGLE TO CLIMB OUT OF THE 20S.
ONCE AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPS...TD...
AND WINDS UP TO 21Z TODAY AND THEN THE SUPERBLEND THROUGH 00Z
TUESDAY. DID MAKE SOME SLIGHT ADJUSTMENTS TO POINT TEMPERATURE DATA
FOR MAXES AND MINS THROUGH THE PERIOD. AS FOR POPS...ENDED UP SIMILAR
TO A BLEND OF THE GUIDANCE TODAY BUT WENT ABOVE ALL OF IT FOR THE
LIGHT RAIN AND SNOW CHANCES LATER THIS EVENING AND THE FIRST PART OF
TONIGHT...MONDAY WAS KEPT DRY IN LINE WITH ALL THE MOS.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 342 AM EST SUN JAN 4 2015
THE EXTENDED PORTION OF THE FORECAST WILL BEGIN ON MONDAY NIGHT WITH
A PROGRESSIVE UPPER LEVEL PATTERN THAT KEEPS A BROAD TROUGH OVER THE
NORTHEASTERN CONUS THROUGH MUCH OF THE EXTENDED. THROUGH
SATURDAY...A SERIES OF SHORTWAVES DIVE SOUTHEAST INTO THE OH VALLEY
REGION. THE FIRST WAVE MOVES THROUGH ON TUESDAY AND THOUGH MOISTURE
STARVED AND MOST OF THE LIFT AND MOISTURE BEING NORTH...WILL KEEP
SOME FLURRIES AND SNOW SHOWERS JUST SKIRTING THE NORTHERN PORTION OF
THE CWA. MODEL SOUNDINGS KEEP THE LOWER LEVELS QUITE DRY SO COULD
ALSO GO COMPLETELY DRY OVER THE AREA WITH THIS FEATURE. THE FIRST
SHOT OF COLDER AIR FILTERS IN BEHIND THIS FRONT FOR WEDNESDAY. THEN
ANOTHER SHORTWAVE MOVES THROUGH LATER IN THE DAY ON WEDNESDAY BUT
THE FRONT BEING DRY WITH THIS ONE WITH JUST CLOUD COVER EXPECTED.
THE COLD AIR BEHIND THIS FEATURE WILL BRING SOME FRIGID AIR INTO
EASTERN KENTUCKY. DOMINANT SURFACE HIGH PRESSURE WILL RESIDE FROM
THE UPPER PLAINS AND MOVES SOUTHEAST INTO THE MS VALLEY AND TN
VALLEY...KEEPING EASTERN KENTUCKY DRY THROUGH MUCH OF THE EXTENDED.
THE COLD AIR AND WIND EXPECTED FOR THURSDAY WILL PRODUCE SOME WIND
CHILLS INTO THE NEGATIVE TEENS. BECAUSE OF THIS...WILL MENTION THIS
IN THE HWO AS WELL AS ISSUE AN SPS FOR THIS. MODELS DIVERGE
SIGNIFICANTLY AT THE END OF THE EXTENDED AS THE GFS KEEPS THE AREA
DRY BUT THE EURO HAS THE THE UPPER TROUGH LIFTING NORTH ALLOWING A
NEW FEATURE TO DEVELOP AND MOVE NORTHEAST OUT OF THE GULF OF
MEXICO. DID GET SOME POPS FROM THE ALL MODEL BLEND SO WENT WITH
SLIGHTLY LOWER POPS KEEP SLIGHT CHANCE OVER THE AREA. THIS IS DUE
TO COLLABORATION WITH NEIGHBORING OFFICES AS WELL AS THE TRENDS OF
THE EURO. THE AIR MASS IN PLACE DURING THAT TIME IS ALSO QUITE DRY TO
OVERCOME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 710 AM EST SUN JAN 4 2015
WITH THE IMMINENT FROPA THE MAIN THREAT OF THE RAIN WILL COME TO AN
END...BUT ANOTHER DISTURBANCE COULD BRING A FEW RAIN SHOWERS BY THE
MIDDLE OF THE AFTERNOON AND LINGERING INTO THE EVENING HOURS. THIS
WILL SEND LOWER CIGS BACK INTO THE AREA...AS WELL. UPSLOPE FLOW AND
FALLING TEMPERATURES WILL ALSO LINGER THE SHOWER THREAT AS A SNOW ONE
FOR A TIME THIS EVENING ALONG WITH FLURRIES FOR MOST PLACES INTO THE
OVERNIGHT HOURS. STILL SOME STRONG 900MB WINDS AROUND 50 KNOTS...
FOUND AHEAD OF THE FRONT SO LLWS WILL REMAIN A CONCERN FOR ANOTHER
HOUR OR TWO...THOUGH MUCH OF THE WINDS ARE NOW MIXING DOWN TO THE SFC
AS THE BOUNDARY APPROACHES. BREEZY CONDITIONS WILL LIKELY CONTINUE
THIS MORNING AND INTO THE AFTERNOON FROM THE SOUTHWEST TO WEST AS
WINDS GUST UP TO 25 KNOTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
606 AM EST Sun Jan 4 2015
...Updated Aviation Discussion...
.SHORT TERM (Now through Monday)...
Issued at 230 AM EST Sun Jan 4 2015
Big weather changes are in store during the short term period as a
strong storm system continues to cross the Ohio Valley. As of 3
am, the latest water vapor imagery and 500 mb RAP heights shows
intense southwesterly flow remaining across the forecast area as the
main shortwave trough lifts through Missouri into northern Illinois.
A secondary PV anomaly is crossing through Oklahoma. At the surface,
a cold front is beginning to move into the LMK CWA. Ahead of this
boundary, conditions are very mild as readings have held up in the
upper 50s to near 60 degrees.
Plan on scattered/numerous rain showers and/or drizzle to persist
through the early morning hours, ending southwest to northeast as
the main upper level forcing lifts into Ohio. Then, for the
remainder of this morning, we`ll be under the influence of a dry
slot, waiting for the aforementioned secondary PV anomaly to pivot
across the Ohio Valley this afternoon. 04.00z guidance still shows a
good amount of PV advection with this wave, low level lapse rates
approaching 8-9C/km and weak instability. Meso-models depict
intermittent convective rain showers developing this afternoon and
some of the perkier ones may be strong enough to mix down gusty
winds 30-35 mph. As temperatures aloft crash and reach -10C, there
will be a brief window where precipitation may changeover to snow
showers, especially north of KY parkways. A quick dusting is
possible on grassy surfaces but overall not expecting any impacts.
High temperatures will occur this morning, then plan on readings to
steadily fall throughout the day, reaching the mid 30s to lower 40s
by mid/late afternoon. Combined with a brisk west wind 10-20 mph and
wind chills will be in the 20s by this evening. Quite a change in 24
hours.
As the new work and school week begins Monday morning, a fresh surge
of Arctic air will have taken hold of the forecast area. Plan on
morning temperatures in the teens to lower 20s. A steady
north/northwest wind will make it feel more like +5 to +10F. High
temperatures will be 15 to 20 degrees below normal, struggling to
reach the upper 20s.
.LONG TERM (Monday Night through Saturday)...
Issued at 248 AM EST Sun Jan 4 2015
...Very Cold Temperatures and Wind Chills Mid-Week...
A small, weakening area of low pressure will zip quickly by to our
north early Tuesday morning. Models have been fairly consistent and
continue to be in decent agreement with this feature, taking the
great majority of its associated precipitation to our north through
Illinois, central/northern Indiana, and Ohio. The best chance for
any dusting in the LMK CWA would be north of a Paoli-Madison line,
with scattered flurries possible as far south as the Interstate 64
corridor. Atmospheric cross-sections continue to show a good amount
of dry air in the low levels, even in the far north of the LMK CWA,
lending credence to the idea that there will be minimal impact here.
A very impressive dome of frigid high pressure will invade from the
northwest behind Tuesday`s system. This high, already very cold to
begin with, will slide across extensive snowpack in the Plains and
Midwest on its way to the Ohio and Tennessee Valleys, limiting
moderation of the airmass. On Wednesday, sunrise temperatures
should be in the teens, and will fall from there into the single
digits in Indiana and the lower and middle teens in Kentucky by
suppertime. Winds will be brisk and gusty in a tight pressure
gradient on the nose of the incoming high, possibly gusting to
around 20 mph as temperatures fall. Wind chills Wednesday afternoon
and evening over southern Indiana and northern Kentucky will be in
the -5 to -15 range.
By dawn on Thursday the center of the high will be right over us.
Any breeze will be light, and what breeze there is may be coming in
from the northwest off the Midwestern snow field. Skies should be
clear. So, very cold temperatures can be expected. Southern
Indiana locations will dip slightly below zero, with lows around
zero in Kentucky all the way down to the Tennessee border.
A weakening cold front will pass through on Friday morning
completely dry with high pressure centers ahead of and behind it,
blocking any moisture supply. Then, behind the departing front,
another Canadian high for Friday night/Saturday.
&&
.AVIATION (12Z TAF Update)...
Issued at 600 AM EST Sun Jan 4 2015
Initial surface front now through BWG/SDF/LEX as winds have turned
to the southwest. Plan on gusts 25-30 kts this morning and a
temporary end to precipitation as the region becomes dry slotted.
Ceilings upstream vary from low end MVFR to SKC, but thinking that
any holes will fill in later today and bases will climb to above
fuel alternate by late morning to afternoon. Another weather
disturbance could bring scattered rain showers to all TAF sites by
the afternoon. Winds will become more northwesterly with this
secondary front passage. Toward the end of the period, soundings
show dry air will work in and ceilings will become more scattered.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Short Term........ZBT
Long Term.........13
Aviation..........ZBT
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1051 AM EST SUN JAN 4 2015
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO LIFT NORTH OF THE AREA THIS MORNING. A
COLD FRONT WILL APPROACH FROM THE WEST TODAY AND MOVE THROUGH THE
AREA TONIGHT. HIGH PRESSURE WILL BE OVER THE AREA MONDAY AND
TUESDAY. A DRY COLD FRONT WILL MOVE THROUGH AREA TUESDAY NIGHT
FOLLOWED BY ARCTIC HIGH PRESSURE BUILDING OVER THE AREA THE
REMAINDER OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1030 AM SUN...LATE MORNING UPDATE ADJUSTED MAINLY TO CAPTURE
PRECIP TRENDS. A PRE-FRONTAL BAND OF MODERATE TO HEAVY SHOWERS
CONTINUES TO PUSH ACROSS THE AREA AND MOST OF THE SHOWER ACTIVITY
HAS PUSHED EAST OF HWY 17. A FEW LIGHTNING STRIKES ALSO SEEN
ACROSS MAINLAND DARE AND MAINLAND HYDE COUNTIES AND WILL KEEP
SLIGHT CHANCE OF THUNDER. HRRR CONTINUES TO HAVE A GOOD HANDLE
ON CURRENT ACTIVITY SHOWING SHOWERS WEAKENING AS THEY CONTINUE TO
PUSH EASTWARD WITH A RELATIVE MINIMUM IN ACTIVITY EARLY THIS
AFTERNOON BEFORE ANOTHER LINE OF SHOWERS ASSOCIATED WITH THE
FRONT...CURRENTLY MOVING ACROSS THE WESTERN PIEDMONT...MOVES INTO
EASTERN NC MID TO LATE AFTERNOON. MARGINAL THREAT OF SVR DUE TO
STRONG WIND FIELDS AND SHEAR...BUT LAPSE RATES WEAK AND CLOUD
COVER AND SCT SHRA COVERAGE WILL INHIBIT INSTABILITY AS WELL. DID
INCLUDE GUSTY WINDS AND HEAVY RAIN MENTIONED LATE AFTN/EARLY EVENING
WITH MAIN FRONTAL BAND PCPN. TEMPS IN UPPER 60S TO LOW 70S LATE
THIS MORNING AND WILL NOT TAKE MUCH INSOLATION TO REACH MID TO UPR
70S FOR MAX TEMPS...WHICH WILL BE NEAR RECORD HIGHS SOME AREAS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
AS OF 400 AM SUNDAY...PER NEAR TERM DISCUSSION...MARGINAL THREAT OF
ISOLATED SVR WIND GUST WITH FRONTAL PCPN BAND MOVING ACROSS DURING
EVENING HOURS. FRONT EXPECTED TO BE OFF COAST SHORTLY AFTER MIDNIGHT
WITH CLEARING SKIES AND COOLER TEMPS MOVING IN OVERNIGHT. LOWS FROM
MID 40S INLAND TO AROUND 50 COAST.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 404 AM SAT...LONG TERM PERIOD WILL START OUT WITH SEASONABLE
TEMPERATURES AND DRY CONDITIONS FOLLOWED BY ARCTIC AIR MASS AND
COLDEST AIR OF THE SEASON BY WEDNESDAY NIGHT THROUGH FRIDAY
MORNING.
FOR MONDAY...SPRAWLING HIGH PRES BUILDS IN FROM THE GREAT LAKES
REGION/OHIO VALLEY WITH TEMPS DROPPING BACK TO NEAR
CLIMO...LOW/MID 50S UNDER SUNNY SKIES. THE HIGH WILL BE CENTERED
OVER THE MID ATLANTIC STATES MONDAY NIGHT WITH EXCELLENT
RADIATIONAL COOLING EXPECTED WITH CALM WINDS AND CLEAR SKIES. LOWS
DROP BACK TO THE 20S AWAY FROM THE COAST TO NEAR FREEZING BEACHES.
ON TUESDAY...FLOW QUICKLY BACKS SOUTH THEN SOUTH IN RESPONSE TO
NEXT DIGGING STRONG SHORTWAVE TO THE WEST. LARGE DIURNAL
TEMPERATURE SWING EXPECTED AS LOW LEVEL THICKNESSES...MOS GUIDE
BOTH SUGGESTING HIGHS INTO THE UPPER 50S TO LOWER 60S...HIGHEST
SOUTH. TUESDAY NIGHT WILL BE RELATIVELY MILD AS WESTERLY LOW LEVEL
FLOW CONTINUES TO KEEP BNDRY LAYER SLIGHTLY MIXED. LOWS WILL BE IN
THE 30S TO NEAR 40.
COLDEST AIR MASS OF THE SEASON LOOKS TO ARRIVE WED INTO THUR.
MED/LONG RANGE MODEL SUITE IN REMARKABLY GOOD AGREEMENT ON DEEP
ARCTIC TROUGH DIGGING INTO THE CENTRAL CONUS ON TUE NIGHT THEN
TRANSLATING TO THE EASTERN CONUS WEDNESDAY NIGHT INTO THUR. TRICKY
TEMP FORECAST ON WED...AS HIGHS MAY BE REALIZED IN THE MORNING
HOURS BEFORE STRONG CAA ENSUES IN THE AFTERNOON WITH TEMPS
DROPPING. COLD AIR ADVECTION WILL STRENGTHEN WED NIGHT WITH WINDS
STAYING ELEVATED IN THE 10 TO 15 MPH RANGE WITH HIGHER GUSTS.
THESE WINDS COMBINED WITH FCST LOWS IN THE MID/UPR TEENS WILL
PRODUCE WIND CHILL VALS WELL INTO THE SINGLE DIGIT RANGE ABOVE
ZERO. WILL CONTINUE TO HIGHLIGHT THE COLD WIND CHILLS IN THE HWO.
THREAT FOR SNOW SHOWERS ACROSS THE OUTER BANKS...NAMELY DARE
COUNTY...AS LOW LEVEL NON SHEARED FLOW WILL VEER TO NNW TO ALMOST
TRUE NORTH BY LATE WED NIGHT. THE GUSTY WINDS FLOWING OVER WARM
SOUND AND OCEAN WATERS COULD PRODUCE SOME `SOUND OR OCEAN EFFECT`
SNOW SHOWERS WED NIGHT THROUGH THUR. ANY ACCUMS SHOULD BE TRIVIAL
AND HAVE INCLUDED CHANCE SNOW SHOWERS IN THE GRIDS FOR DARE
COUNTY.
THURSDAY WILL BE QUITE COLD WITH HIGHS STILL EXPECTED TO BE AROUND
FREEZING OR JUST BELOW. WINDS WILL BEGIN TO DIMINISH AS GRADIENT
BEGINS TO RELAX...THOUGH STILL EXPECT WIND CHILLS TO BE IN THE
TEENS TO LOWER 20S IN THE AFTERNOON. ANOTHER COLD NIGHT THURSDAY
NIGHT IN THE TEENS WITH ARCTIC HIGH TRANSLATING OVER THE
AREA...THOUGH VERY LITTLE WIND AND WIND CHILL VALS SHOULD NOT BE
MUCH OF AN ISSUE.
A SLOW MODERATION IN TEMPS FRI INTO NEXT WEEKEND AS HEIGHTS SHOULD
REMAIN A BIT BELOW NORMAL PER ENSEMBLE MEMBERS AND THEREFORE HIGHS
EXPECTED IN THE 40S TO LOWER 50S. NEXT PRECIP CHANCE COULD ARRIVE
LATE IN THE WEEKEND THOUGH STILL LOTS OF UNCERTAINTY WITH RETURN
FLOW.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
SHORT TERM /THROUGH 12Z MONDAY/...
AS OF 1030 AM SUNDAY...PRE-FRONTAL BAND OF SHRA HAS PUSHED EAST OF
TAF SITES. EXPECT ISOL-SCT SHOWERS THROUGH EARLY AFTERNOON WITH A
MIX OF MVFR/VFR CONDITIONS. ANOTHER WDSPRD BAND OF SHOWERS/ISOLD
TSTMS WILL PUSH THROUGH LATER THIS AFTERNOON AND EVENING JUST
AHEAD OF FRONT BRINGING MAINLY MVFR CONDITIONS. FRONT WILL MOVE
ACROSS AREA BY MIDNIGHT WITH WINDS SHIFTING TO W-NW AND SKIES
CLEARING OVERNIGHT. SW WINDS WILL GUST TO AROUND 25 KT TODAY...AND
ISOLD SVR WIND GUST PSBL WITH ISOLD TSTMS MAINLY LATE AFTN INTO
EARLY EVENING.
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 404 AM SUN...DRY AIRMASS WILL MOVE IN ON MONDAY WITH SKIES
QUICKLY BECOMING MOSTLY CLEAR. VFR MONDAY WITH LIGHT NORTHWEST
FLOW. SURFACE WINDS BECOME SOUTHWEST TUESDAY AROUND 10 KNOTS AHEAD
OF NEXT FRONT. A DRY COLD FRONT WILL PASS THROUGH WEDNESDAY WITH
WINDS NORTHWEST 10-15 KNOTS WITH HIGHER GUSTS. NW WINDS WILL
REMAIN ELEVATED ON WED NIGHT WITH DRY ARCTIC AIRMASS MOVING IN AND
LINGERING THROUGH THURSDAY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1030 AM SUNDAY...LITTLE CHANGE TO PREVIOUS FCST WINDS AND
SEAS AS MODELS REMAIN IN GOOD AGREEMENT WITH INCREASING S-SW WINDS
INTO THIS EVENING AHEAD OF APPROACHING COLD FRONT...THEN WINDS
SHIFTING TO NW OVERNIGHT WITH FRONTAL PASSAGE. SEAS EXPECTED TO
PEAK AT 7-10 FT THIS AFTERNOON AND EVENING...THEN GRADUALLY
SUBSIDE INTO MONDAY.
LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 404 AM SUN...WINDS AND SEAS WILL SLOWLY DIMINISH MONDAY AS
HIGH PRESSURE BUILDS IN FROM THE WEST. SCA SHOULD END ON MONDAY.
SW TO W FLOW INCREASES ON TUESDAY AS A STRONG WAVE MOVES BY TO THE
NORTH AND PRODUCES A PERIOD OF SCA WINDS AND SEAS LATE TUE. WINDS
MAY DIMINISH A BIT WED BUT QUICKLY STRENGTHEN WITH PASSAGE OF A
STRONG COLD FRONT. WINDS BEHIND THE FRONT WILL BE IN THE STRONG
SCA RANGE AND COULD SEE A PERIOD OF GALES WED NIGHT INTO EARLY
THUR AS MOST MODELS INDICATING WINDS GUSTING 35 TO 40 KT. WINDS
WILL DIMINISH BY THUR AFTERNOON AND THEN VEER NE FRI AS ANOTHER
AREA OF HIGH PRES PASSES BY TO THE NORTH.
&&
.HYDROLOGY...
MINOR FLOODING IN THE NEUSE RIVER AT KINSTON WILL CONTINUE. THE
NEUSE RIVER IS FORECAST TO REMAIN AT MINOR FLOOD LEVELS THROUGH MID
WEEK. SEE THE LATEST FLSMHX FOR DETAILS.
&&
.CLIMATE...
RECORD HIGH TEMPERATURES POSSIBLE ON SUNDAY JANUARY 4 2015. BELOW IS
A LIST OF ASOS/AWOS/COOP STATIONS AND THE YEAR OF THEIR RECORD HIGHS
FOR SUNDAY.
VALUE LOCATION YEAR
===== ======== ====
78 NEW BERN 2004
78 GREENVILLE 2000
75 KINSTON 7SE 2000
75 CAPE HATTERAS 1972
75 MOREHEAD CITY1950
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST MONDAY FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 4 AM EST MONDAY FOR AMZ130.
SMALL CRAFT ADVISORY UNTIL 4 PM EST MONDAY FOR AMZ150-152-154-
156-158.
&&
$$
SYNOPSIS...JBM
NEAR TERM...SEK/JBM
SHORT TERM...JBM
LONG TERM...TL
AVIATION...SEK/JBM/TL
MARINE...SEK/JBM/TL
HYDROLOGY...JBM
CLIMATE...SEK/TL
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
740 AM EST SUN JAN 4 2015
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO LIFT NORTH OF THE AREA THIS MORNING. A
COLD FRONT WILL APPROACH FROM THE WEST TODAY AND MOVE THROUGH THE
AREA TONIGHT. HIGH PRESSURE WILL BE OVER THE AREA MONDAY AND
TUESDAY. A DRY COLD FRONT WILL MOVE THROUGH AREA TUESDAY NIGHT
FOLLOWED BY ARCTIC HIGH PRESSURE BUILDING OVER THE AREA THE
REMAINDER OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 730 AM SUN...UPDATED FOR INCREASED POPS ACROSS MOST OF AREA
THIS MORNING. PRE-FRONTAL BAND OF SHOWERS HAS BECOME WDSPRD WITH
CONVECTIVE PARAMETERS INDICATING STRONGER WIND GUSTS PSBL WITH
HEAVIER ACTIVITY. LATEST HRRR HAS GOOD HANDLE ON CURRENT ACTIVITY
AND UPDATED BASED ON IT WITH WDSPRD BAND OF SHRA/ISOLD TSTM MOVING
NE ACROSS AREA THIS MORNING. MODEL INDICATES ACTIVITY WLL BECOME SCT
NEAR COAST THIS AFTN...THEN ADDITIONAL ACTIVITY MOVING IN FROM W
WITH FRONT TOWARD EVENING.
/PREVIOUS DISCUSSION/
AS OF 400 AM SUNDAY...WARM FRONT HAS LIFTED INLAND AND N OF AREA
OVERNIGHT WITH ALL AREAS NOW AFFECTED BY WARM SRLY WINDS WHICH HAS
PUSHED TEMPS AND DEW PTS INTO 60S ALL AREASS...AND EVEN SOME LOW 70S
SRN SECTIONS. COLD FRONT STILL APPROACHING THE MTNS FROM OH AND TN
VLYS BUT PRE-FRONTAL BAND OF SHOWERS/ISOLD TSTMS HAS DEVELOPED WITH
SRLY INFLUX AND SPREADING FROM ERN SC INTO COASTAL PLAINS...AND
LATEST MODELS INDICATE THIS ACTIVITY WILL PERSIST THROUGH MORNING.
INCREASED POPS TO LIKELY ALONG AND W OF HWY 17 BASED ON THIS WITH
SHC/SCT POP WORDING E OF HWY 17. CONTINUED PREVIOUS FCST TREND OF
INCREASING POPS DURING AFTN AS MAIN FRONTAL BAND APPROACHES FROM W
AND SCT ACTIVITY CONTINUES E. MARGINAL THREAT OF SVR DUE TO STRONG
WIND FIELDS AND SHEAR...BUT LAPSE RATES WEAK AND CLOUD COVER AND SCT
SHRA COVERAGE WILL INHIBIT INSTABILITY AS WELL. DID INCLUDE GUSTY
WINDS AND HEAVY RAIN MENTION LATE AFTN/EARLY EVENING WITH MAIN
FRONTAL BAND PCPN WORDING.
WITH TEMPS ALREADY INTO MID 60S TO LOW 70S OVER AREA...WILL NOT TAKE
MUCH INSOLATION TO REACH MID TO UPR 70S FOR MAX TEMPS...WHICH WILL
BE NEAR RECORD HIGHS SOME AREAS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
AS OF 400 AM SUNDAY...PER NEAR TERM DISCUSSION...MARGINAL THREAT OF
ISOLATED SVR WIND GUST WITH FRONTAL PCPN BAND MOVING ACROSS DURING
EVENING HOURS. FRONT EXPECTED TO BE OFF COAST SHORTLY AFTER MIDNIGHT
WITH CLEARING SKIES AND COOLER TEMPS MOVING IN OVERNIGHT. LOWS FROM
MID 40S INLAND TO AROUND 50 COAST.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 404 AM SAT...LONG TERM PERIOD WILL START OUT WITH SEASONABLE
TEMPERATURES AND DRY CONDITIONS FOLLOWED BY ARCTIC AIR MASS AND
COLDEST AIR OF THE SEASON BY WEDNESDAY NIGHT THROUGH FRIDAY
MORNING.
FOR MONDAY...SPRAWLING HIGH PRES BUILDS IN FROM THE GREAT LAKES
REGION/OHIO VALLEY WITH TEMPS DROPPING BACK TO NEAR
CLIMO...LOW/MID 50S UNDER SUNNY SKIES. THE HIGH WILL BE CENTERED
OVER THE MID ATLANTIC STATES MONDAY NIGHT WITH EXCELLENT
RADIATIONAL COOLING EXPECTED WITH CALM WINDS AND CLEAR SKIES. LOWS
DROP BACK TO THE 20S AWAY FROM THE COAST TO NEAR FREEZING BEACHES.
ON TUESDAY...FLOW QUICKLY BACKS SOUTH THEN SOUTH IN RESPONSE TO
NEXT DIGGING STRONG SHORTWAVE TO THE WEST. LARGE DIURNAL
TEMPERATURE SWING EXPECTED AS LOW LEVEL THICKNESSES...MOS GUIDE
BOTH SUGGESTING HIGHS INTO THE UPPER 50S TO LOWER 60S...HIGHEST
SOUTH. TUESDAY NIGHT WILL BE RELATIVELY MILD AS WESTERLY LOW LEVEL
FLOW CONTINUES TO KEEP BNDRY LAYER SLIGHTLY MIXED. LOWS WILL BE IN
THE 30S TO NEAR 40.
COLDEST AIR MASS OF THE SEASON LOOKS TO ARRIVE WED INTO THUR.
MED/LONG RANGE MODEL SUITE IN REMARKABLY GOOD AGREEMENT ON DEEP
ARCTIC TROUGH DIGGING INTO THE CENTRAL CONUS ON TUE NIGHT THEN
TRANSLATING TO THE EASTERN CONUS WEDNESDAY NIGHT INTO THUR. TRICKY
TEMP FORECAST ON WED...AS HIGHS MAY BE REALIZED IN THE MORNING
HOURS BEFORE STRONG CAA ENSUES IN THE AFTERNOON WITH TEMPS
DROPPING. COLD AIR ADVECTION WILL STRENGTHEN WED NIGHT WITH WINDS
STAYING ELEVATED IN THE 10 TO 15 MPH RANGE WITH HIGHER GUSTS.
THESE WINDS COMBINED WITH FCST LOWS IN THE MID/UPR TEENS WILL
PRODUCE WIND CHILL VALS WELL INTO THE SINGLE DIGIT RANGE ABOVE
ZERO. WILL CONTINUE TO HIGHLIGHT THE COLD WIND CHILLS IN THE HWO.
THREAT FOR SNOW SHOWERS ACROSS THE OUTER BANKS...NAMELY DARE
COUNTY...AS LOW LEVEL NON SHEARED FLOW WILL VEER TO NNW TO ALMOST
TRUE NORTH BY LATE WED NIGHT. THE GUSTY WINDS FLOWING OVER WARM
SOUND AND OCEAN WATERS COULD PRODUCE SOME `SOUND OR OCEAN EFFECT`
SNOW SHOWERS WED NIGHT THROUGH THUR. ANY ACCUMS SHOULD BE TRIVIAL
AND HAVE INCLUDED CHANCE SNOW SHOWERS IN THE GRIDS FOR DARE
COUNTY.
THURSDAY WILL BE QUITE COLD WITH HIGHS STILL EXPECTED TO BE AROUND
FREEZING OR JUST BELOW. WINDS WILL BEGIN TO DIMINISH AS GRADIENT
BEGINS TO RELAX...THOUGH STILL EXPECT WIND CHILLS TO BE IN THE
TEENS TO LOWER 20S IN THE AFTERNOON. ANOTHER COLD NIGHT THURSDAY
NIGHT IN THE TEENS WITH ARCTIC HIGH TRANSLATING OVER THE
AREA...THOUGH VERY LITTLE WIND AND WIND CHILL VALS SHOULD NOT BE
MUCH OF AN ISSUE.
A SLOW MODERATION IN TEMPS FRI INTO NEXT WEEKEND AS HEIGHTS SHOULD
REMAIN A BIT BELOW NORMAL PER ENSEMBLE MEMBERS AND THEREFORE HIGHS
EXPECTED IN THE 40S TO LOWER 50S. NEXT PRECIP CHANCE COULD ARRIVE
LATE IN THE WEEKEND THOUGH STILL LOTS OF UNCERTAINTY WITH RETURN
FLOW.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
SHORT TERM /THROUGH 12Z MONDAY/...
AS OF 630 AM SUNDAY...PRE-FRONTAL BAND OF SHRA WILL MOVE ACROSS TAF
SITES THROUGH 15Z WITH MAINLY MVFR CIGS AND VSBYS. CONDITIONS
IMPROVED TO MVFR CIGS/VFR VSBYS ALL SITES OVERNIGHT AS WARM FRONT
LIFTED N...AND MVFR CIGS EXPECTED TO PERSIST THROUGH MORNING. SCT
SHRA AND ISOLD TSTMS PSBL THROUGH THE DAY IN PRE-FRONTAL WARM
SECTOR...WITH CIGS LIFTING TO VFR THIS AFTN. ANOTHER WDSPRD BAND OF
SHOWERS/ISOLD TSTMS THIS EVENING JUST AHEAD OF FRONT WITH MAINLY
MVFR CONDITIONS. FRONT WILL MOVE ACROSS AREA BY MIDNIGHT WITH WINDS
SHIFTING TO W-NW AND SKIES CLEARING OVERNIGHT. SW WINDS WILL GUST TO
AROUND 25 KT TODAY...AND ISOLD SVR WIND GUST PSBL WITH ISOLD TSTMS
MAINLY LATE AFTN INTO EARLY EVENING.
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 404 AM SUN...DRY AIRMASS WILL MOVE IN ON MONDAY WITH SKIES
QUICKLY BECOMING MOSTLY CLEAR. VFR MONDAY WITH LIGHT NORTHWEST
FLOW. SURFACE WINDS BECOME SOUTHWEST TUESDAY AROUND 10 KNOTS AHEAD
OF NEXT FRONT. A DRY COLD FRONT WILL PASS THROUGH WEDNESDAY WITH
WINDS NORTHWEST 10-15 KNOTS WITH HIGHER GUSTS. NW WINDS WILL
REMAIN ELEVATED ON WED NIGHT WITH DRY ARCTIC AIRMASS MOVING IN AND
LINGERING THROUGH THURSDAY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 730 AM SUNDAY...ADJUSTED POPS/WX WORDING PER NEAR TERM
DISCUSSION...OTHERWISE NO CHANGES WITH UPDATE.
/PREVIOUS DISCUSSION/
AS OF 400 AM SUNDAY...WARM FRONT HAS LIFTED N AND GUSTY SRLY WINDS
HAVE DEVELOPED OVER ALL THE WATERS...AND SCA ON TRACK. ALLOWED
MARINE DENSE FOG ADVSY TO EXPIRE AT 4 AM...BUT ISSUED MWS TO HANDLE
PESKY LINGERING AREAS OF FOG OVER ALB SOUND AND ALLIGATOR
RVR...EXPECTED TO LIFT BY 8 AM.
LITTLE CHANGE TO PREVIOUS FCST WINDS AND SEAS AS MODELS REMAIN IN
GOOD AGREEMENT WITH INCREASING S-SW WINDS INTO THIS EVENING AHEAD OF
APPROACHING COLD FRONT...THEN WINDS SHIFTING TO NW OVERNIGHT WITH
FRONTAL PASSAGE. SEAS EXPECTED TO PEAK AT 7-10 FT THIS
EVENING...THEN GRADUALLY SUBSIDE INTO MONDAY.
LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 404 AM SUN...WINDS AND SEAS WILL SLOWLY DIMINISH MONDAY AS
HIGH PRESSURE BUILDS IN FROM THE WEST. SCA SHOULD END ON MONDAY.
SW TO W FLOW INCREASES ON TUESDAY AS A STRONG WAVE MOVES BY TO THE
NORTH AND PRODUCES A PERIOD OF SCA WINDS AND SEAS LATE TUE. WINDS
MAY DIMINISH A BIT WED BUT QUICKLY STRENGTHEN WITH PASSAGE OF A
STRONG COLD FRONT. WINDS BEHIND THE FRONT WILL BE IN THE STRONG
SCA RANGE AND COULD SEE A PERIOD OF GALES WED NIGHT INTO EARLY
THUR AS MOST MODELS INDICATING WINDS GUSTING 35 TO 40 KT. WINDS
WILL DIMINISH BY THUR AFTERNOON AND THEN VEER NE FRI AS ANOTHER
AREA OF HIGH PRES PASSES BY TO THE NORTH.
&&
.HYDROLOGY...
MINOR FLOODING IN THE NEUSE RIVER AT KINSTON WILL CONTINUE. THE
NEUSE RIVER IS FORECAST TO REMAIN AT MINOR FLOOD LEVELS THROUGH MID
WEEK. SEE THE LATEST FLSMHX FOR DETAILS.
&&
.CLIMATE...
RECORD HIGH TEMPERATURES POSSIBLE ON SUNDAY JANUARY 4 2015. BELOW IS
A LIST OF ASOS/AWOS/COOP STATIONS AND THE YEAR OF THEIR RECORD HIGHS
FOR SUNDAY.
VALUE LOCATION YEAR
===== ======== ====
78 NEW BERN 2004
78 GREENVILLE 2000
78 BAYBORO 3E 1972
75 KINSTON 7SE 2000
75 WILLIAMSTON 2000
75 CAPE HATTERAS 1972
70 MANTEO AP 2005
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST MONDAY FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 4 AM EST MONDAY FOR AMZ130.
SMALL CRAFT ADVISORY UNTIL 4 PM EST MONDAY FOR AMZ150-152-154-
156-158.
&&
$$
SYNOPSIS...JBM
NEAR TERM...JBM
SHORT TERM...JBM
LONG TERM...TL
AVIATION...JBM/TL
MARINE...JBM/TL
HYDROLOGY...JBM
CLIMATE...TL
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1043 AM EST SUN JAN 4 2015
.SYNOPSIS...
COLD FRONT CROSSES THIS AFTERNOON. GUSTY WINDS AND SNOW SHOWERS
FLURRIES IN ITS WAKE TONIGHT INTO MONDAY MORNING. HIGH PRESSURE
MONDAY EVENING. FAST CLIPPER TUESDAY FOLLOWED BY ARCTIC BLAST
WEDNESDAY/THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1030 AM UPDATE. FOCUSING ON BAND OF SHOWERS ALONG COLD FRONT THAT
WILL CROSS THE REMAINDER OF THE AREA THIS AFTERNOON...WITH GUSTY
WINDS.
PREVIOUS DISCUSSION...
ENHANCED POPS A BIT WITH THE SHOWERS RIGHT ALONG THE FRONT OUT TO
THE W. FCST OTHERWISE LARGELY ON TRACK.
PREV DISCN...
LOW PRESSURE CENTER DRAGS A COLD FRONT THROUGH THE AREA TODAY AS IT
CONSOLIDATES OVER THE EASTERN GREAT LAKES. MAIN PLUME OF RAINFALL
GOOD FOR ABOUT AN INCH GIVE OR TAKE OVER A 6 HOUR PERIOD EXITS FIRST
THING THIS MORNING. SHOWERS ACCOMPANY AND IMMEDIATELY FOLLOW THE
FRONT ITSELF...STILL IN WRN OHIO EARLY THIS MORNING AND W OF THE
FCST AREA AT DAWN.
THE FRONT WILL PUSH THROUGH THE AREA LATER THIS MORNING THROUGH
EARLY THIS AFTERNOON W TO E. STRONG PRESSURE GRADIENT WITH PRESSURE
RISE OF 8 MB/6 HRS THIS AFTERNOON INTO TONIGHT SUGGEST GOOD MIXING
AND MOMENTUM TRANSPORT. USED RUC MOMENTUM ALGORITHM TO ARRIVE AT
GUSTS TO 30 KTS HILLTOPS DURING THE FRONTAL PASSAGE TODAY AND
CONTINUING SEVERAL HOURS AFTER...WITH UP TO 40 KTS OVER THE HIGHER
TERRAIN...THESE GUSTS MAY PERSIST THERE MUCH OF THE NT TONIGHT.
THESE VALUES FALL SHY OF ADV CRITERIA THOUGH.
AFTER A DRY SLOT LATER TODAY...UPSLOPE SHOW SHOWERS SHOULD INCREASE
OVER THE HIGHER WINDWARD TERRAIN TONIGHT AS H85 TEMPERATURES CRASH
TO -10C OR LOWER OVERNIGHT...SUPPORTIVE OF ICE CRYSTALS. AM A
LITTLE UNDER WWD WITH UP TO AN INCH OVER THE HIGHER WINDWARD
TERRAIN. MOISTURE DEPTH INCREASES AS MAIN UPPER LEVEL S/W TROUGH
AXIS CROSSES THIS EVENING...ALSO GIVING RISE TO CRYSTAL GROWTH AND
SCATTERED RAIN SHOWERS CHANGING TO SNOW SHOWERS EVEN OUT ACROSS THE
LOWLANDS EARLY TONIGHT. OTHERWISE STRATOCU PERSISTS BENEATH
LOWERING SUBSIDENCE INVERSION THROUGH THE BALANCE OF THE NEAR TERM
PERIOD.
BLENDED IN MAINLY NAM BASED HOURLY TEMPERATURES IN THE STRONG COLD
ADVECTION...HIGHS OCCUR EARLY TODAY.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
PERIOD WILL BEGIN WITH SMALL CHANCES OF SNOW IN THE MOUNTAINS.
HOWEVER...ANY PRECIPITATION SHOULD END QUICKLY AS HIGH PRESSURE
MOVES EAST ACROSS THE REGION. THIS HIGH SHOULD RESULT IN DRY
WEATHER REGION-WIDE BY LATE MONDAY MORNING....AND CONTINUE INTO
MONDAY NIGHT.
A FAST MOVING LOW PRESSURE SYSTEM WILL THEN BRING PRECIPITATION
CHANCES BACK TO THE REGION LATE MONDAY NIGHT. MODELS DIFFER ON THE
TRACK OF THE LOW AND ASSOCIATED PRECIPITATION...WITH THE NAM
LIMITING ANY MEASURABLE TO OUR EXTREME NORTHERN AREAS. THE
GFS/ECMWF AND HPC 6-HR PRECIPITATION FORECAST SUGGESTS THE EDGE OF
THE MEASURABLE PRECIPITATION WILL BE FARTHER SOUTH. HAVE TWEAKED
THE POPS AND QPF GRIDS TOWARDS THE SOLUTION OF THE GFS/ECMWF/HPC.
AS A RESULT...HAVE LIKELY OR HIGHER POPS ACROSS OUR NORTHERN TWO
TIER OF COUNTIES FROM LATE MONDAY NIGHT INTO TUESDAY AFTERNOON.
BEHIND THE LOW...COLDER AIR AND WESTERLY WINDS WILL COMBINE WITH
SUFFICIENT MOISTURE TO BRING A GOOD CHANCE OF UPSLOPE SNOW TUESDAY
EVENING INTO THE OVERNIGHT HOURS.
THE UPSLOPE SNOW SHOULD DECREASE BY LATE TUESDAY NIGHT. HOWEVER...
ANOTHER UPPER LEVEL SYSTEM WILL SWEEP SOUTHEAST ACROSS THE AREA ON
WEDNESDAY...WITH SNOW SHOWERS CHANCES CONTINUING.
MET/MAV GUIDANCE IS QUITE CLOSE FOR MONDAY THROUGH TUESDAY...AND WAS
CLOSE TO WHAT WE HAVE IN OUR GRIDS...SO DID NOT MAKE ANY MAJOR
CHANGES. MEX GUIDANCE IS ALSO CLOSE TO OUR GRIDS FOR TUESDAY NIGHT
AND WEDNESDAY...SO ONLY SOME MINOR TWEAKS WERE MADE.
CURRENT THINKING IS THAT SNOWFALL AMOUNTS UP TO 2 INCHES ARE
POSSIBLE ACROSS OUR NORTHERN COUNTIES FROM LATE MONDAY NIGHT THROUGH
TUESDAY...WITH A FEW INCHES POSSIBLE IN THE NORTHERN MOUNTAINS LATE
TUESDAY THROUGH TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
FRONT END OF THE EXTENDED DEALS WITH THE TAIL END OF THE CLIPPER
TYPE LOW PRESSURE SYSTEM WITH DECREASING CHANCES OF SNOW OVER THE
NORTHERN TIER OF THE CWA THROUGH TUESDAY NIGHT. IN THE WAKE OF THE
SYSTEM...UPPER LEVEL LOW DEEPENS OVER THE GREAT LAKES WHILE SURFACE
HIGH PRESSURE BUILDS OVER THE MIDWEST AS IT MOVES IN FROM THE LEE OF
THE CANADIAN ROCKIES. OF INTEREST IS THE ECMWF THAT HAS THE HIGH
REACHING 1060MB OVER THE BLACK HILLS AREA IN SOUTH DAKOTA.
THAT HIGH PRESSURE SHOULD BE GOOD TO GO THROUGH THE END OF THE
WEEK...ALTHOUGH MAY NEED TO WATCH FOR ANOTHER GREAT LAKES CLIPPER
TYPE SYSTEM FRIDAY. LOW CONFIDENCE WITH THIS AT THIS POINT.
NOT TOO MANY CHANGES TO THE TEMPERATURES WEDNESDAY THROUGH THURSDAY
WITH HIGHS STRUGGLING TO HIT 20F AND LOWS BELOW 0F POSSIBLE
WEDNESDAY NIGHT. SKIES SHOULD CLEAR...BUT WIND STAYS UP...SO
RADIATIONAL COOLING NOT EXPECTED AT THIS TIME. THIS WILL KEEP VALLEY
TEMPERATURES FROM DROPPING FURTHER.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
16Z SUNDAY THRU 12Z MONDAY...
COLD FRONT MOVES THROUGH THE AREA THIS AFTERNOON. AHEAD OF THE FRONT
VFR CEILINGS. FRONT BRINGS GUSTY RAIN SHOWERS WITH MVFR CONDITIONS.
BEHIND THE FRONT...GUSTY WEST WINDS CONTINUE. A BRIEF PERIOD OF VFR
CEILINGS POSSIBLE BEFORE STRONG COLD ADVECTION BRINGS MVFR CEILINGS
BACK INTO THE AREA LATER THIS AFTERNOON. FOR TONIGHT...GENERAL MVFR
WITH SCATTERED FLURRIES LOW LANDS AND MVFR/IFR SNOW SHOWERS
MOUNTAINS...ALONG WITH GUSTY WEST WINDS ESPECIALLY RIDGETOPS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z MONDAY...
FORECAST CONFIDENCE: MEDIUM
ALTERNATE SCENARIO: TIMING OF LOWER CIGS AND WIND GUSTS WILL VARY.
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 M 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 M M M M
PKB CONSISTENCY H H H H M H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z MONDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED AT THIS TIME.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/TRM
NEAR TERM...TRM/JMV
SHORT TERM...JSH
LONG TERM...26
AVIATION...TRM/JMV
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
530 AM EST SUN JAN 4 2015
.SYNOPSIS...
COLD FRONT CROSSES TODAY. GUSTY WINDS AND SNOW SHOWERS FLURRIES IN
ITS WAKE TONIGHT INTO MONDAY MORNING. HIGH PRESSURE MONDAY EVENING.
FAST CLIPPER TUESDAY FOLLOWED BY ARCTIC BLAST WEDNESDAY/THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
ENHANCED POPS A BIT WITH THE SHOWERS RIGHT ALONG THE FRONT OUT TO
THE W. FCST OTHERWISE LARGELY ON TRACK.
PREV DISCN...
LOW PRESSURE CENTER DRAGS A COLD FRONT THROUGH THE AREA TODAY AS IT
CONSOLIDATES OVER THE EASTERN GREAT LAKES. MAIN PLUME OF RAINFALL
GOOD FOR ABOUT AN INCH GIVE OR TAKE OVER A 6 HOUR PERIOD EXITS FIRST
THING THIS MORNING. SHOWERS ACCOMPANY AND IMMEDIATELY FOLLOW THE
FRONT ITSELF...STILL IN WRN OHIO EARLY THIS MORNING AND W OF THE
FCST AREA AT DAWN.
THE FRONT WILL PUSH THROUGH THE AREA LATER THIS MORNING THROUGH
EARLY THIS AFTERNOON W TO E. STRONG PRESSURE GRADIENT WITH PRESSURE
RISE OF 8 MB/6 HRS THIS AFTERNOON INTO TONIGHT SUGGEST GOOD MIXING
AND MOMENTUM TRANSPORT. USED RUC MOMENTUM ALGORITHM TO ARRIVE AT
GUSTS TO 30 KTS HILLTOPS DURING THE FRONTAL PASSAGE TODAY AND
CONTINUING SEVERAL HOURS AFTER...WITH UP TO 40 KTS OVER THE HIGHER
TERRAIN...THESE GUSTS MAY PERSIST THERE MUCH OF THE NT TONIGHT.
THESE VALUES FALL SHY OF ADV CRITERIA THOUGH.
AFTER A DRY SLOT LATER TODAY...UPSLOPE SHOW SHOWERS SHOULD INCREASE
OVER THE HIGHER WINDWARD TERRAIN TONIGHT AS H85 TEMPERATURES CRASH
TO -10C OR LOWER OVERNIGHT...SUPPORTIVE OF ICE CRYSTALS. AM A
LITTLE UNDER WWD WITH UP TO AN INCH OVER THE HIGHER WINDWARD
TERRAIN. MOISTURE DEPTH INCREASES AS MAIN UPPER LEVEL S/W TROUGH
AXIS CROSSES THIS EVENING...ALSO GIVING RISE TO CRYSTAL GROWTH AND
SCATTERED RAIN SHOWERS CHANGING TO SNOW SHOWERS EVEN OUT ACROSS THE
LOWLANDS EARLY TONIGHT. OTHERWISE STRATOCU PERSISTS BENEATH
LOWERING SUBSIDENCE INVERSION THROUGH THE BALANCE OF THE NEAR TERM
PERIOD.
BLENDED IN MAINLY NAM BASED HOURLY TEMPERATURES IN THE STRONG COLD
ADVECTION...HIGHS OCCUR EARLY TODAY.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
PERIOD WILL BEGIN WITH SMALL CHANCES OF SNOW IN THE MOUNTAINS.
HOWEVER...ANY PRECIPITATION SHOULD END QUICKLY AS HIGH PRESSURE
MOVES EAST ACROSS THE REGION. THIS HIGH SHOULD RESULT IN DRY
WEATHER REGION-WIDE BY LATE MONDAY MORNING....AND CONTINUE INTO
MONDAY NIGHT.
A FAST MOVING LOW PRESSURE SYSTEM WILL THEN BRING PRECIPITATION
CHANCES BACK TO THE REGION LATE MONDAY NIGHT. MODELS DIFFER ON THE
TRACK OF THE LOW AND ASSOCIATED PRECIPITATION...WITH THE NAM
LIMITING ANY MEASURABLE TO OUR EXTREME NORTHERN AREAS. THE
GFS/ECMWF AND HPC 6-HR PRECIPITATION FORECAST SUGGESTS THE EDGE OF
THE MEASURABLE PRECIPITATION WILL BE FARTHER SOUTH. HAVE TWEAKED
THE POPS AND QPF GRIDS TOWARDS THE SOLUTION OF THE GFS/ECMWF/HPC.
AS A RESULT...HAVE LIKELY OR HIGHER POPS ACROSS OUR NORTHERN TWO
TIER OF COUNTIES FROM LATE MONDAY NIGHT INTO TUESDAY AFTERNOON.
BEHIND THE LOW...COLDER AIR AND WESTERLY WINDS WILL COMBINE WITH
SUFFICIENT MOISTURE TO BRING A GOOD CHANCE OF UPSLOPE SNOW TUESDAY
EVENING INTO THE OVERNIGHT HOURS.
THE UPSLOPE SNOW SHOULD DECREASE BY LATE TUESDAY NIGHT. HOWEVER...
ANOTHER UPPER LEVEL SYSTEM WILL SWEEP SOUTHEAST ACROSS THE AREA ON
WEDNESDAY...WITH SNOW SHOWERS CHANCES CONTINUING.
MET/MAV GUIDANCE IS QUITE CLOSE FOR MONDAY THROUGH TUESDAY...AND WAS
CLOSE TO WHAT WE HAVE IN OUR GRIDS...SO DID NOT MAKE ANY MAJOR
CHANGES. MEX GUIDANCE IS ALSO CLOSE TO OUR GRIDS FOR TUESDAY NIGHT
AND WEDNESDAY...SO ONLY SOME MINOR TWEAKS WERE MADE.
CURRENT THINKING IS THAT SNOWFALL AMOUNTS UP TO 2 INCHES ARE
POSSIBLE ACROSS OUR NORTHERN COUNTIES FROM LATE MONDAY NIGHT THROUGH
TUESDAY...WITH A FEW INCHES POSSIBLE IN THE NORTHERN MOUNTAINS LATE
TUESDAY THROUGH TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
FRONT END OF THE EXTENDED DEALS WITH THE TAIL END OF THE CLIPPER
TYPE LOW PRESSURE SYSTEM WITH DECREASING CHANCES OF SNOW OVER THE
NORTHERN TIER OF THE CWA THROUGH TUESDAY NIGHT. IN THE WAKE OF THE
SYSTEM...UPPER LEVEL LOW DEEPENS OVER THE GREAT LAKES WHILE SURFACE
HIGH PRESSURE BUILDS OVER THE MIDWEST AS IT MOVES IN FROM THE LEE OF
THE CANADIAN ROCKIES. OF INTEREST IS THE ECMWF THAT HAS THE HIGH
REACHING 1060MB OVER THE BLACK HILLS AREA IN SOUTH DAKOTA.
THAT HIGH PRESSURE SHOULD BE GOOD TO GO THROUGH THE END OF THE
WEEK...ALTHOUGH MAY NEED TO WATCH FOR ANOTHER GREAT LAKES CLIPPER
TYPE SYSTEM FRIDAY. LOW CONFIDENCE WITH THIS AT THIS POINT.
NOT TOO MANY CHANGES TO THE TEMPERATURES WEDNESDAY THROUGH THURSDAY
WITH HIGHS STRUGGLING TO HIT 20F AND LOWS BELOW 0F POSSIBLE
WEDNESDAY NIGHT. SKIES SHOULD CLEAR...BUT WIND STAYS UP...SO
RADIATIONAL COOLING NOT EXPECTED AT THIS TIME. THIS WILL KEEP VALLEY
TEMPERATURES FROM DROPPING FURTHER.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
COLD FRONT WHIPS THROUGH THE AREA TODAY...BRINGING STRONG GUSTY
WINDS AND WIDESPREAD MVFR CIGS.
CONDITIONS MANAGED TO STAY MAINLY VFR IN THE RAIN OVERNIGHT IN THE
GUSTY S FLOW. EXPECT IT WILL TAKE THE PASSAGE OF THE COLD FRONT AND
ITS ASSOCIATED WIND SHIFT TO MANIFEST MVFR STRATOCU LATER THIS
MORNING.
OTHERWISE SHOWERS WITH THE FRONT TODAY SHOULD NOT AMOUNT TO MUCH
OTHER THAN WIND GUSTS. AFTER A DRY SLOT THIS AFTERNOON...RAIN
SHOWERS WILL FORM AGAIN LATE TODAY AND CHANGE OVER TO SNOW SHOWERS
TONIGHT. THEY WILL BE SCATTERED AND LIGHT ACROSS THE LOWLANDS AND
DIMINISH THERE OVERNIGHT TONIGHT. SNOW SHOWERS WILL BE MORE
NUMEROUS IN THE MOUNTAINS TONIGHT...WITH MVFR OR WORSE VSBY POSSIBLE
AT TIMES OVERNIGHT AT EKN.
WINDS AHEAD OF THE FRONT HAVE TENDED TO VARY FROM SE TO SW AND HAVE
BEEN OCCASIONALLY GUSTY. BEHIND THE FRONT TODAY...WINDS WILL SHIFT
TO W TO SW...AND QUICKLY BECOME GUSTY IN THE STRONG COLD ADVECTION
BEHIND THE FRONT...HAVE GUSTS OF 25 TO 30 KTS CODED UP FOR THIS
AFTERNOON INTO TONIGHT. THE STRONGEST GUSTS ARE MOST LIKELY RIGHT
WITH THE FRONT...AND THEN FOR A SHORT TIME AROUND SUNSET THIS
EVENING. THESE STRONG WINDS WILL ONLY SLOWLY DIMINISH
OVERNIGHT...BUT STILL BE GUSTY COME MON MORNING. STRONG SW FLOW
ALOFT TODAY WILL BECOME MODERATE W BEHIND THE FRONT FOR LATE TODAY
THROUGH TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIO: TIMING OF LOWER CIGS AND WIND GUSTS WILL VARY.
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 M H H H H H H H H
HTS CONSISTENCY H H H H H H H M H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H M H H H H H H M
PKB CONSISTENCY H H H H H H H M M M H H
CKB CONSISTENCY H H H H H H H H H H M H
AFTER 12Z MONDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED AT THIS TIME.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/TRM
NEAR TERM...TRM
SHORT TERM...JSH
LONG TERM...26
AVIATION...TRM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
734 AM EST SUN JAN 4 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE REGION TODAY...BUT IT WILL BE
VERY MILD BEFORE THE FRONT PASSES. TEMPERATURES WILL THEN TREND
SIGNIFICANTLY COLDER FOR THE REST OF THE WEEK. AN ALBERTA CLIPPER
WILL BRING SOME SNOW MONDAY NIGHT AND TUESDAY BEFORE ARCTIC AIR
SETTLES IN FOR MID WEEK. LAKE EFFECT AND UPSLOPE SNOWS WILL LAST
THROUGH MUCH OF THE WEEK OVER THE NORTHWEST MOUNTAINS AND LAUREL
HIGHLANDS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
630 AM UPDATE...
WILL HOLD OFF ON A DENSE FOG ADVY...WITH MANY OBS ACTUALLY COMING
UP A TINY BIT THESE LAST FEW HRS. MAIN AREA OF RAIN PUSHING TO THE
EAST AND COLD FRONT IS JUST TO OUR N/W. DEWPOINTS NOW CLOSE TO 50F
IN BFD AND JST - BUT FIG STUCK IN THE M30S FOR TEMP/DEW. MADE
TWEAKS FOR THE TEMPS BUT THE REST OF THE FCST REMAINS UNCHANGED.
PREV...
IN WHAT IS AN UNUSUAL EVENT FOR JANUARY...KJST IS EXPERIENCING THE
NICEST WEATHER OF ALL THE OB SITES IN THE AREA. FOG IS GETTING
FAIRLY DENSE ACROSS THE SE...AND MAY NEED AN ADVY SOON AS NO WIND
IS EXPECTED THERE TO HELP IT MIX AWAY BEFORE SUNRISE. WILL PONDER
THIS JUST A LITTLE WHILE LONGER...AS NO OBS ARE CURRENTLY BELOW
1/4SM. RAIN IS AGAIN SPREADING OVER ALL THE AREA AS A WEAK SHORT
WAVE TROUGH PUSHES IN FROM THE WEST. SO FAR...NO THUNDER HAS
HAPPENED AS THE FRONT HAS STARTED TO MAKE WAY THROUGH NRN OH...SO
WILL JUST KEEP THE MENTION OF THUNDER TO MYSELF FOR NOW.
HOWEVER...THE RAP AND NAM DO PROG SOME MEAGER INSTABILITY AND
BOUYANCY TO DEVELOP IN THE FAR NW BEFORE SUNRISE...AND THEN AGAIN
OVER THE FAR SE LATE THIS AFTN/EARLY EVENING AS THE FRONT SLIDES
THROUGH. HOWEVER...IT IS STABLE AND PROGGED TO STAY THAT WAY AT
THE SFC OVER 95PCT OF CENTRAL PA.
TEMPS HARDLY MOVING AT THIS TIME...WITH SOME ISOLATED POCKETS OF
32F AIR TEMPS LEFT AT THIS HOUR. HOWEVER...THE VAST MAJORITY OF
THE AREA HAS AIR TEMPS ABOVE FREEZING. STILL...THE SLUSHY SFC MAY
BE KEEPING THE TEMPS AT OR BELOW FREEZING RIGHT AT THE GROUND
LEVEL...AND NOT 2M UP. THUS...UNTREATED ROADS IN THE CENTRAL AND
EASTERN ZONES MAY STILL BE SLIPPERY. TEMPS SHOULD RISE AS THE DAY
CONTINUES...WITH MAXES IN THE 50S POSSIBLE IN THE SOUTHEAST IF THE
WIND ALOFT CAN MIX DOWN AND BRING THE 10C AIR WITH IT.
COLD FRONT SHOULD CROSS THE AREA STEADILY THRU THE DAY...AND TEMPS
WILL BE DROPPING IN THE AFTN OVER THE NW. THUS...P-TYPE IS LIKELY
TO CHANGE AS THE TEMPS IN THE COLUMN DROP THERE LATER TODAY. WILL
JUST CALL IT A MIX OF RW/SW.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
8H TEMPS CONTINUE TO DROP STEADILY TONIGHT AND MONDAY - REACHING
-22C IN THE FAR N BY MONDAY EVENING. SFC TEMPS SHOULD STAY PRETTY
STEADY OR EVEN FALL ON MONDAY DUE TO THE STRONG COLD ADVECTION.
THIS WILL BRING THE USUAL AND CUSTOMARY LAKE EFFECT AND UPSLOPE
SNOW SHOWERS TO THE WEST. A LIGHT ACCUMULATION IS EXPECTED FOR
TONIGHT AND MONDAY...WITH THE HIGHEST NUMBERS OF 2-3 INCHES OVER
THE 24 HR PERIOD IN THE FAR NW - NOT QUITE WORTH AN ADVY. SFC
PRESSURES RISE INTO THE 1030-PLUS RANGE MONDAY NIGHT...WITH THE
CENTER OF THE HIGH TO OUR SOUTH. WINDS DO GO SRLY MONDAY NIGHT
AHEAD OF A POTENT SHORT WAVE ZIPPING ALONG IN THE FAST W-E FLOW.
THE WAVE WILL BE CLIPPING ALONG WITH FULL SAILS...AND SHOULD START
TO MAKE LIGHT...FLUFFY SNOW AROUND MIDNIGHT MON NIGHT. THIS SNOW
IS WELL- AGREED UPON BY THE MODEL SOLUTIONS. THE TRACK OF THE MOST
IMPORTANT THING WITH A CLIPPER - THE SFC LOW AND BEST LIFT AND
BEST SNOW BAND WHICH IS ATTENDANT IMMEDIATELY TO IT/S NORTH - IS
STILL SOMEWHAT UNCERTAIN. BUT MOST MODELS DO BRING A MINOR LOW
JUST TO THE SOUTH OF THE STATE...A GOOD SPOT FOR IT TO GO FOR
LOCAL SNOW. WILL GO AHEAD AND HOIST CATEGORICAL POPS OVER THE NRN
TWO-THIRDS OF THE AREA...AND LIKELIES IN THE SOUTH. QPF GENERALLY
0.15 TO 0.3 INCHES IN THE PLACES WHERE SNOW IS EXPECTED - AND THE
FLUFFINESS OF THE SNOW WHILE 8H TEMPS ARE IN THE TEENS BELOW ZERO
C - WILL PROBABLY CAUSE SNOW OF 1-3 IF NOT 2-4 INCHES. BUT THE
TRACK QUESTION KEEPS FORECASTER CONFIDENCE TOO LOW AND THE TIME
RANGE ITSELF TOO FAR IN THE FUTURE TO MAKE AN ADVY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A LONG WAVE TROUGH DEEPENS MID-WEEK AND A DEEP LAYER OF
SIGNIFICANTLY COLDER AIR SHOULD MARCH INTO THE REGION. 850MB
TEMPERATURES COULD BE IN THE -20C TO -30C RANGE. THIS COULD ALLOW
FOR SFC HIGHS ON WEDNESDAY TO THURSDAY TO BE 20 DEGREES OR GREATER
BELOW NORMAL. COUPLE THIS WITH WINDS THAT WILL BE N TO NE EARLY
ON...THE EDGE OF MUCH COLDER AIR CAN WORK TO THE SOUTH AND NOT BE
MODIFIED MUCH BY THE LAKES. SOME DIRECTIONAL SHEAR EARLY ON...BUT
SIGNIFICANT LAKE EFFECT WILL BE POSSIBLE AS WINDS SHIFT MORE TO
THE NW. STILL NOT AS COLD AS WHAT WE SAW IN EARLY JANUARY LAST
YEAR. COLDEST AIR REMAINS NORTH OF THE LOWER LAKES WITH SECONDARY
HIGH PRESSURE OVER ONTARIO AND QUEBEC.
THE DEEP UPPER LEVEL TROUGH SHOULD TILT POSITIVELY AND LIFT TO
THE NORTHEAST...WHICH SHOULD BRING CLOSER TO NORMAL TEMPS NEXT
WEEKEND. WINDS SHOULD SHIFT MORE TO THE SW DUE TO A RIDGE
BUILDING OVER THE REGION.
&&
.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
RAIN HAS BECOME SHOWERY AS LAST PUSH OF PRE FRONTAL PRECIP HAS
MOVED EAST OF THE REGION. HOWEVER...SIGNIFICANT CIG AND VSBY
RESTRICTIONS STILL EXIST. WARMING TEMPERATURES OVER EVEN A LITTLE
ICE/SNOW/SLEET ON THE GROUND...WILL LEAD FOR RAPID LOCALIZED FOG
FORMATION WHERE WINDS SLACKEN.
ALTHOUGH THERE MAY BE OCCASIONAL IMPROVEMENTS IN VISIBILITY...HIGH
CONFIDENCE THAT CIGS WILL REMAIN IN THE IFR TO LIFR CATEGORY
THROUGH THE REST OF THE MORNING HOURS.
A STRONG SSWLY LLJ WILL CONTINUE TO ADVECT MILDER AIR INTO THE
AREA. THIS 50+KT LLJ WILL ALSO SUPPORT LLWS AT ALL AIRFIELDS
THROUGH THE DAY TODAY.
SHOWERS ARE EXPECTED AHEAD OF A COLD FRONT THIS AFTN FOLLOWED BY
A COLDER AND GUSTY NORTHWEST FLOW SUNDAY NIGHT INTO MONDAY.
EXPECT TYPICAL OROGRAPHIC RAIN/SNOW SHOWERS AND REDUCED VISIBILITIES
IN THE MOUNTAINS LATER SUNDAY INTO MONDAY IN THE COLD NW UPSLOPE
FLOW. IMPROVING CONDITIONS ARE EXPECTED EAST OF THE MOUNTAINS IN
DOWNSLOPE FLOW.
CLIPPER SYSTEM WILL LIKELY BRING LIGHT SNOW TO THE REGION TUESDAY...
FOLLOWED BY MORE SNOW SHOWERS FOR THE WESTERN TAFS THROUGH THE
REMAINDER OF THE WEEK.
OUTLOOK...
MON...MVFR/IFR WEST WITH -SHSN. VFR CENTRAL/EAST.
TUE...MVFR/IFR LKLY IN -SN FROM CLIPPER.
WED-THU...MVFR/IFR WITH -SHSN WEST. VFR/MVFR CIGS CENTRAL/EAST.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...DANGELO
AVIATION...JUNG/GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
645 AM EST SUN JAN 4 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE REGION TODAY...BUT IT WILL BE
VERY MILD BEFORE THE FRONT PASSES. TEMPERATURES WILL THEN TREND
SIGNIFICANTLY COLDER FOR THE REST OF THE WEEK. AN ALBERTA CLIPPER
WILL BRING SOME SNOW MONDAY NIGHT AND TUESDAY BEFORE ARCTIC AIR
SETTLES IN FOR MID WEEK. LAKE EFFECT AND UPSLOPE SNOWS WILL LAST
THROUGH MUCH OF THE WEEK OVER THE NORTHWEST MOUNTAINS AND LAUREL
HIGHLANDS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
630 AM UPDATE...
WILL HOLD OFF ON A DENSE FOG ADVY...WITH MANY OBS ACTUALLY COMING
UP A TINY BIT THESE LAST FEW HRS. MAIN AREA OF RAIN PUSHING TO THE
EAST AND COLD FRONT IS JUST TO OUR N/W. DEWPOINTS NOW CLOSE TO 50F
IN BFD AND JST - BUT FIG STUCK IN THE M30S FOR TEMP/DEW. MADE
TWEAKS FOR THE TEMPS BUT THE REST OF THE FCST REMAINS UNCHANGED.
PREV...
IN WHAT IS AN UNUSUAL EVENT FOR JANUARY...KJST IS EXPERIENCING THE
NICEST WEATHER OF ALL THE OB SITES IN THE AREA. FOG IS GETTING
FAIRLY DENSE ACROSS THE SE...AND MAY NEED AN ADVY SOON AS NO WIND
IS EXPECTED THERE TO HELP IT MIX AWAY BEFORE SUNRISE. WILL PONDER
THIS JUST A LITTLE WHILE LONGER...AS NO OBS ARE CURRENTLY BELOW
1/4SM. RAIN IS AGAIN SPREADING OVER ALL THE AREA AS A WEAK SHORT
WAVE TROUGH PUSHES IN FROM THE WEST. SO FAR...NO THUNDER HAS
HAPPENED AS THE FRONT HAS STARTED TO MAKE WAY THROUGH NRN OH...SO
WILL JUST KEEP THE MENTION OF THUNDER TO MYSELF FOR NOW.
HOWEVER...THE RAP AND NAM DO PROG SOME MEAGER INSTABILITY AND
BOUYANCY TO DEVELOP IN THE FAR NW BEFORE SUNRISE...AND THEN AGAIN
OVER THE FAR SE LATE THIS AFTN/EARLY EVENING AS THE FRONT SLIDES
THROUGH. HOWEVER...IT IS STABLE AND PROGGED TO STAY THAT WAY AT
THE SFC OVER 95PCT OF CENTRAL PA.
TEMPS HARDLY MOVING AT THIS TIME...WITH SOME ISOLATED POCKETS OF
32F AIR TEMPS LEFT AT THIS HOUR. HOWEVER...THE VAST MAJORITY OF
THE AREA HAS AIR TEMPS ABOVE FREEZING. STILL...THE SLUSHY SFC MAY
BE KEEPING THE TEMPS AT OR BELOW FREEZING RIGHT AT THE GROUND
LEVEL...AND NOT 2M UP. THUS...UNTREATED ROADS IN THE CENTRAL AND
EASTERN ZONES MAY STILL BE SLIPPERY. TEMPS SHOULD RISE AS THE DAY
CONTINUES...WITH MAXES IN THE 50S POSSIBLE IN THE SOUTHEAST IF THE
WIND ALOFT CAN MIX DOWN AND BRING THE 10C AIR WITH IT.
COLD FRONT SHOULD CROSS THE AREA STEADILY THRU THE DAY...AND TEMPS
WILL BE DROPPING IN THE AFTN OVER THE NW. THUS...P-TYPE IS LIKELY
TO CHANGE AS THE TEMPS IN THE COLUMN DROP THERE LATER TODAY. WILL
JUST CALL IT A MIX OF RW/SW.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
8H TEMPS CONTINUE TO DROP STEADILY TONIGHT AND MONDAY - REACHING
-22C IN THE FAR N BY MONDAY EVENING. SFC TEMPS SHOULD STAY PRETTY
STEADY OR EVEN FALL ON MONDAY DUE TO THE STRONG COLD ADVECTION.
THIS WILL BRING THE USUAL AND CUSTOMARY LAKE EFFECT AND UPSLOPE
SNOW SHOWERS TO THE WEST. A LIGHT ACCUMULATION IS EXPECTED FOR
TONIGHT AND MONDAY...WITH THE HIGHEST NUMBERS OF 2-3 INCHES OVER
THE 24 HR PERIOD IN THE FAR NW - NOT QUITE WORTH AN ADVY. SFC
PRESSURES RISE INTO THE 1030-PLUS RANGE MONDAY NIGHT...WITH THE
CENTER OF THE HIGH TO OUR SOUTH. WINDS DO GO SRLY MONDAY NIGHT
AHEAD OF A POTENT SHORT WAVE ZIPPING ALONG IN THE FAST W-E FLOW.
THE WAVE WILL BE CLIPPING ALONG WITH FULL SAILS...AND SHOULD START
TO MAKE LIGHT...FLUFFY SNOW AROUND MIDNIGHT MON NIGHT. THIS SNOW
IS WELL- AGREED UPON BY THE MODEL SOLUTIONS. THE TRACK OF THE MOST
IMPORTANT THING WITH A CLIPPER - THE SFC LOW AND BEST LIFT AND
BEST SNOW BAND WHICH IS ATTENDANT IMMEDIATELY TO IT/S NORTH - IS
STILL SOMEWHAT UNCERTAIN. BUT MOST MODELS DO BRING A MINOR LOW
JUST TO THE SOUTH OF THE STATE...A GOOD SPOT FOR IT TO GO FOR
LOCAL SNOW. WILL GO AHEAD AND HOIST CATEGORICAL POPS OVER THE NRN
TWO-THIRDS OF THE AREA...AND LIKELIES IN THE SOUTH. QPF GENERALLY
0.15 TO 0.3 INCHES IN THE PLACES WHERE SNOW IS EXPECTED - AND THE
FLUFFINESS OF THE SNOW WHILE 8H TEMPS ARE IN THE TEENS BELOW ZERO
C - WILL PROBABLY CAUSE SNOW OF 1-3 IF NOT 2-4 INCHES. BUT THE
TRACK QUESTION KEEPS FORECASTER CONFIDENCE TOO LOW AND THE TIME
RANGE ITSELF TOO FAR IN THE FUTURE TO MAKE AN ADVY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A LONG WAVE TROUGH DEEPENS MID-WEEK AND A DEEP LAYER OF
SIGNIFICANTLY COLDER AIR SHOULD MARCH INTO THE REGION. 850MB
TEMPERATURES COULD BE IN THE -20C TO -30C RANGE. THIS COULD ALLOW
FOR SFC HIGHS ON WEDNESDAY TO THURSDAY TO BE 20 DEGREES OR GREATER
BELOW NORMAL. COUPLE THIS WITH WINDS THAT WILL BE N TO NE EARLY
ON...THE EDGE OF MUCH COLDER AIR CAN WORK TO THE SOUTH AND NOT BE
MODIFIED MUCH BY THE LAKES. SOME DIRECTIONAL SHEAR EARLY ON...BUT
SIGNIFICANT LAKE EFFECT WILL BE POSSIBLE AS WINDS SHIFT MORE TO
THE NW. STILL NOT AS COLD AS WHAT WE SAW IN EARLY JANUARY LAST
YEAR. COLDEST AIR REMAINS NORTH OF THE LOWER LAKES WITH SECONDARY
HIGH PRESSURE OVER ONTARIO AND QUEBEC.
THE DEEP UPPER LEVEL TROUGH SHOULD TILT POSITIVELY AND LIFT TO
THE NORTHEAST...WHICH SHOULD BRING CLOSER TO NORMAL TEMPS NEXT
WEEKEND. WINDS SHOULD SHIFT MORE TO THE SW DUE TO A RIDGE
BUILDING OVER THE REGION.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
PRECIPITATION HAS BECOME MUCH MORE SHOWERY DURING THE LAST THREE
HOURS...BUT SIGNIFICANT CIG AND VSBY RESTRICTIONS STILL EXIST.
WARMING TEMPERATURES OVER EVEN A LITTLE ICE/SNOW/SLEET ON THE
GROUND...WILL LEAD FOR RAPID LOCALIZED FOG FORMATION WHERE WINDS
SLACKEN.
ALTHOUGH THERE MAY BE OCCASIONAL IMPROVEMENTS IN VISIBILITY...HIGH
CONFIDENCE THAT CIGS WILL REMAIN IN THE IFR TO LIFR CATEGORY
OVERNIGHT.
A STRONG SSWLY LLJ WILL CONTINUE TO ADVECT MILDER AIR INTO THE
AREA. THIS 50+KT LLJ WILL ALSO SUPPORT LLWS AT ALL AIRFIELDS
OVERNIGHT AND THROUGH THE DAY SUNDAY.
SHOWERS ARE EXPECTED AHEAD OF A COLD FRONT ON SUNDAY FOLLOWED BY
A COLDER AND GUSTY NORTHWEST FLOW SUNDAY NIGHT INTO MONDAY.
EXPECT TYPICAL OROGRAPHIC RAIN/SNOW SHOWERS AND REDUCED VISIBILITIES
IN THE MOUNTAINS LATER SUNDAY INTO MONDAY IN THE COLD NW UPSLOPE
FLOW. IMPROVING CONDITIONS ARE EXPECTED EAST OF THE MOUNTAINS IN
DOWNSLOPE FLOW.
CLIPPER SYSTEM WILL LIKELY BRING LIGHT SNOW TO THE REGION TUESDAY...
FOLLOWED BY MORE SNOW SHOWERS FOR THE WESTERN TAFS THROUGH THE
REMAINDER OF THE WEEK.
OUTLOOK...
MON...MVFR/IFR WEST WITH -SHSN. VFR CENTRAL/EAST.
TUE...MVFR/IFR LKLY IN -SN FROM CLIPPER.
WED-THU...MVFR/IFR WITH -SHSN WEST. VFR/MVFR CIGS CENTRAL/EAST.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...DANGELO
AVIATION...JUNG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
920 AM EST SUN JAN 4 2015
.SYNOPSIS...
A COLD FRONT WILL SWEEP ACROSS THE REGION TODAY...WITH DRYING
EXPECTED TONIGHT. A VERY COLD AND DRY WEEK IS EXPECTED...WITH ARCTIC
AIR SPILLING INTO THE REGION MID TO LATE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 915 AM EST SUNDAY...LINE OF PREFRONTAL SHOWERS WITH A FEW
EMBEDDED THUNDERSTORMS CONTINUES TO SLIDE EAST INTO THE NC/SC
PIEDMONT THIS MORNING. LATEST SBCAPE ANALYSIS VIA SPC MESO AND
LOCAL LAPS INDICATES THE PERSISTENT WEDGE HAS LIMITED INSTABILITY
SUBSTANTIALLY. THAT SAID...STILL A MODERATE AMOUNT OF LOW LEVEL
SHEAR IN PLACE AS EVIDENT BY LATEST RADAR VELOCITY RETURNS SO CANNOT
RULE OUT SOME GUSTY WINDS. AS FOR THE FCST...MODIFIED POPS BY
MOVING POP TRENDS UP A FEW HOURS DUE TO LATEST HRRR RUNS INDICATING
EARLY AFTN CONVECTION IS UNLIKELY. THUS...POPS DECREASE FROM WEST
TO EAST LATE THIS MORNING. OTHERWISE...NO SIGNIFICANT CHANGES AT
THIS TIME.
PREVIOUS DISCUSSION...
AS OF 645 AM...ANOTHER UPDATE TO THE TEMPS/DWPTS...FOLLOWING THE
TRACK OF THE WEDGE FRONT ACRS THE SOUTHERN TIER OF COUNTIES.
ALSO...MONITORING CONVECTIVE TRENDS ACRS NE GA INTO THE UPSTATE.
THERE IS ABOUT 100 J/KG OF MUCAPE ACRS THE PIEDMONT AHEAD OF THE
LINE. WITH SUCH STRONG BULK SHEAR...A FEW STRONGER CELLS MAY BE ABLE
TO PRODUCE STRONG DOWNDRAFTS AND LLVL ROTATION. I HAVE BUMPED UP THE
THUNDER MENTION TO ABOUT 30%...ROUGHLY ALONG I-85 AND SOUTH. ALL
OTHER TRENDS LOOK ABOUT ON TRACK.
AS OF 415 AM...ANOTHER QUICK UPDATE TO THE TEMPS TO BETTER MATCH UP
WITH THE OBS...AS A WARM WEDGE FRONT PUSHES NORTH INTO THE CWFA.
TEMP GRADIENT IS PRETTY SHARP...WITH EQY AND GRD AT 63...WHILE
KAND/KCLT ARE AROUND 48. ALSO...I HAVE ALLOWED THE DENSE FOG ADV TO
EXPIRE. NO METARS IN THE CWFA ARE LESS THAN 1/2SM ATTM.
AS OF 330 AM...THE WEDGE FRONT IS MAKING PROGRESS NORTHWARD ACRS
CENTRAL GA AND THE MIDLANDS ATTM. THIS SHUD SCOUR OUT THE DENSE FOG
AS IT PUSHES INTO THE LWR PIEDMONT AND CHARLOTTE METRO AREA WITHIN
THE NEXT HOUR OR TWO. I WILL PLAN TO ALLOW THE DENSE FOG ADV TO
EXPIRE AT 4 AM. MEANWHILE...THE PRE-FRONTAL BAND OF MODERATE TO
HEAVY RAIN SLOWLY PUSHES INTO THE CWFA FROM THE WEST. STILL EXPECT
THIS BAND TO CROSS THE AREA DURING THE MORNING HOURS...GETTING TO
THE I-77 CORRIDOR BY EARLY AFTN. RAIN RATES OF 0.5 TO 1.0" PER HOUR
ARE OCCURRING WITHIN THE RAIN SHIELD ACRS AL AND NW GA. THE LATEST
FFG GUIDANCE FOR NE GA AND SRN ESCARPMENT IS 1.75-2.50" IN 3
HRS...AND 2.25-3.50" IN 6 HOURS. SO I STILL THINK THE STREAMS CAN
MANAGE THE INCOMING RAIN...WITH AN ISOLD HYDRO/FLOOD THREAT POSSIBLE.
OTHERWISE...THE MAIN CONCERN WILL BE ANY SEVERE THREAT AS THE
STRONGLY SHEARED LINE OF CONVECTION CROSSES THE CWFA TODAY. MOST
GUIDANCE STILL ONLY UNCOVERING 200-300 J/KG OF CAPE AT MOST ALONG
THE SE FRINGE OF THE CWFA. AS USUAL...THE NAM HAS MORE CAPE (UP 500
J/KG...WELL TO THE WEST ACRS THE ENTIRE PIEDMONT. THE LATEST DAY 1
CONVECTIVE OUTLOOK HAS THE MARGINAL RISK JUST CLIPPING UNION NC. IT
STILL LOOKS LIKE A NON-ZERO WIND THREAT AND TORNADO THREAT. WILL
CONTINUE TO MENTION IN THE HWO.
TEMPS WILL BE TRICKY EARLY ON...AS UNCOVERED WARM SECTOR IS IN THE
MID-UPR 60S...WHILE THE WEDGE IS IN THE MID-UPR 40S. SOME LOCATIONS
SOUTH AND EAST OF I-85 MAY SPIKE INTO THE UPR 60S TO NEAR 70 BEFORE
THE CONVECTION MOVES THRU.
THIS AFTN THRU TONIGHT...GUSTY SW WINDS ARE EXPECTED BEHIND THE RAIN
SHIELD...THEN THE SFC COLD FRONT WILL PUSH THRU AND SHIFT THE WINDS
OUT OF THE NW. FROM THERE THE STRONGER/GUSTY WINDS WILL BE IN THE
HIGH TERRAIN...WITH THE HIGHEST PEAKS LIKELY SEEING 40-50 MPH GUSTS.
FCST SNDGS ALSO SHOW SHALLOW MOISTURE LINGERING WITHIN THE NWLY
FLOW. A FEW SHWRS MAY DEVELOP ALONG THE TN/NC BORDER. TEMPS WILL
PLUMMET INTO THE 20S AND 30S...WITH A FEW SNOW SHWRS AND/OR FREEZING
DRIZZLE MIXING IN OVERNIGHT. POPS ARE ONLY IN THE 20-30% RANGE...AND
LITTLE TO NO ACCUM IS EXPECTED. TEMPS OUTSIDE THE MTNS SHUD FALL
INTO THE MID-UPR 30S UNDER CLEARING SKIES AND DIMINISHING NW WINDS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
AS OF 200 AM SUNDAY...SHORT RANGE MODELS INDICATE THAT A DRY
CANADIAN AIR MASS WILL BUILD OVER THE REGION ON MONDAY...IN THE WAKE
OF SUNDAY/S COLD FRONT. H85 CAA WILL SLOW DURING THE MORNING
HOURS...THEN BECOME NEUTRAL DURING THE AFTERNOON HOURS. THE CWA
SHOULD SEE SUNNY CONDITIONS WITH LIGHT DOWNSLOPE FLOW...FAVORING
AFTERNOON DEWPOINTS IN THE TEENS TO L20S. A BLEND OF MOS GUIDANCE
SUPPORT HIGH TEMPERATURES RANGING FROM NEAR 40 WITHIN THE MTN VALLEYS
TO AROUND 50 ACROSS THE UPPER SAVANNAH RIVER VALLEY.
WEAK RETURN FLOW IS FORECAST TO DEVELOP ACROSS THE REGION MONDAY
NIGHT INTO TUESDAY. AT THE MID LEVELS...THE AXIS OF A SHALLOW L/W
TROF WILL RIPPLE ACROSS THE EASTERN STATES...WITH A POTENT VORT MAX
EXPECTED TO TRACK ACROSS THE MID ATLANTIC STATES ON TUES. AT THE
SFC...LOW PRESSURE WILL LIKELY SLOWLY ORGANIZE OVER THE DELMARVA.
GUIDANCE INDICATES THAT MIN AND MAX TEMPS ON TUES WILL RANGE VERY
CLOSE TO NORMAL. FORECAST SOUNDINGS INDICATE ENOUGH MIXING TO
SUPPORT A MENTION OF MARGINAL WIND GUSTS FROM THE SW DURING THE
DAYLIGHT HOURS ON TUESDAY.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 245 AM SUNDAY...A AMPLIFIED MID LEVEL TROF WILL DIG ACROSS
EASTERN CANADA ON WEDNESDAY...WITH RIDGING BUILDING ACROSS THE PAC
NW. MEDIUM RANGE GUIDANCE SHOWS A 1050+MB HIGH SLIDING ACROSS THE
NRN PLAINS ON WED...WITH THE CENTER OF THE HIGH REACHING THE SRN
APPALACHIANS ON THURS. STRONG CAA WILL BEGIN ON WEDNESDAY...PEAKING
EARLY THURSDAY MORNING...AS LOW AS -20C ACROSS THE NRN MTNS. H85
TEMPS WILL SHOULD START TO RECOVER ON THURSDAY WITH LIGHT RETURN
FLOW. WED HIGHS WILL RANGE AROUND 10 DEGREES BELOW NORMAL. ON
THURSDAY...MIN TEMPS ARE FORECAST TO RANGE FROM NEAR ZERO ACROSS THE
NRN MTNS TO LOW TO MID TEENS ACROSS THE FOOTHILLS AND
PIEDMONT....HIGHS WILL GENERALLY REMAIN BELOW FREEZING. THURSDAY
NIGHT...MINS WILL FALL BACK INTO THE TEENS AND 20S. TEMPERATURES
COULD BE BELOW FREEZING FOR A SOLID 24 TO 48 HOURS FOR A GOOD PART
OF THE AREA. AN HWO COLD WAVE MENTION WILL CONTINUE. IN
ADDITION...DEWPOINTS WILL FALL SHARPLY WITH THE ARRIVAL OF THE
ARCTIC AIR MASS...SEE FIRE WEATHER DISCUSSION.
PREVIOUS DISCUSSION...FAIRLY MAJOR MODEL DIFFERENCES DEVELOP LATE
WEEK...WITH THE ERN TROUGH GETTING REINFORCED BY SHORTWAVE ENERGY
THU NIGHT/FRI ON THE ECMWF...WHILE SHALLOW RIDGING DEVELOPS ON THE
GFS. THE ECMWF AND ENSEMBLES HAVE SHOWN BETTER CONTINUITY AND WILL
BE FAVORED. WILL THUS FOLLOW THE IDEA OF A CLIPPER SYSTEM ARRIVING
IN THE NW FLOW...WITH ANY ATTENDANT SHALLOW MOISTURE STAYING N OF
THE REGION LATE WEEK. THE COLD AIR WILL GET SLIGHTLY REINFORCED FRI
THROUGH FRI NIGHT...WITH SFC HIGH PRESSURE BUILDING OVER TO THE N OF
THE REGION. HEIGHTS SHOULD THEN FINALLY BEGIN RISING UNDER A
SHORTWAVE RIDGE FRI NIGHT INTO SAT...WITH DIVING REDEVELOPING
FROM THE MIDWEST TO THE PLAINS. ANY RETURN FLOW MOISTURE AHEAD OF
THIS SYSTEM SHOULD REMAIN TO THE WEST THROUGH LATE SATURDAY...AS WE
CONTINUE TO FOLLOW THE ECMWF SOLUTION ON THIS TIMING. THIS SHOULD
KEEP CAD FROM FORMING UNTIL JUST BEYOND THE CURRENT FORECAST PERIOD.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...BOTH THE BAND OF SHRA TO THE WEST...AND THE
WEDGE FRONT TO THE SOUTH HAVE STALLED EARLY THIS MORNING.
HOWEVER...THE PRECIP SHIELD SHUD START TO MAKE A PUSH ACRS THE
PIEDMONT WITHIN THE NEXT 2-3 HOURS. OVERALL...CONDITIONS HAVE BEEN
IMPROVING SLIGHTLY. AS THE LINE MOVES ACRS...WILL SEE A MIXTURE OF
MVFR AND IFR CIGS/VSBY. THERE MAY BE SOME THUNDER WITHIN THE LINE OF
SHRA NEAR KAND AND KCLT TODAY. HAVE A VCTS AT KAND...AND A TEMPO AT
KCLT. THERE IS ALSO SOME LLWS NORTH OF THE WEDGE FRONT...WHERE SFC
WINDS HAVE FAVORED A NW DIRECTION...WHILE A SW WIND OF 25-35 KTS
EXISTS AROUND 1500-2000 FT. WILL KEEP A MENTION OF LLWS IN THE
PIEDMONT SITES UNTIL THE SFC WINDS START TO MIX OUT OF THE SOUTH.
LATER TODAY...CONDITIONS SHUD IMPROVE TO VFR BY LATE AFTN. WINDS
WILL INCREASE OUT OF THE SOUTHWEST BEHIND THE LINE OF SHRA...THEN
SHIFT TO NW AND DIMINISH SOMEWHAT THIS EVENING. AT KAVL...CHANNELED
VALLEY WINDS WILL INCREASE TONIGHT...AND BRIEF PERIODS OF MVFR CIGS
WILL BE POSSIBLE FROM NW FLOW MOISTURE.
OUTLOOK...A SERIES OF COLD...DRY HIGH PRESSURE SYSTEMS WILL DROP OUT
OF CANADA...AND DOMINATE THE WEATHER ACRS THE REGION THRU THE WEEK.
CONFIDENCE TABLE...
14-20Z 20-02Z 02-08Z 08-12Z
KCLT MED 69% HIGH 89% HIGH 100% HIGH 100%
KGSP MED 75% HIGH 93% HIGH 100% HIGH 100%
KAVL MED 68% HIGH 100% HIGH 100% MED 70%
KHKY MED 79% HIGH 83% HIGH 100% HIGH 100%
KGMU HIGH 95% HIGH 91% HIGH 100% HIGH 100%
KAND HIGH 84% HIGH 87% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.FIRE WEATHER...
A COLD FRONT WILL MOVE THROUGH THE REGION ON WEDNESDAY...ALLOWING
DRY ARCTIC AIR TO SPILL IN FROM THE NORTHWEST. ALTHOUGH THIS WILL
MEAN MUCH COLDER TEMPERATURES FOR WED AND THU...THE BOUNDARY LAYER
WILL BECOME EXTREMELY DRY. MIN RH VALUES IN THE TEENS AND 20S WILL
BE LIKELY FOR WED AND THU....AND BREEZY TO WINDY CONDITIONS MAY SET
UP AS WELL. FIRE DANGER COULD BE HEIGHTENED IF FINE FUELS DRY OUT
SUFFICIENTLY FOLLOW THE WEEKEND RAIN. THE SITUATION WILL NEED TO BE
MONITORED FOR POSSIBLE INCLUSION IN THE HWO...OR A FIRE WX
WATCH...AT SOME POINT.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...NED
NEAR TERM...ARK/CDG
SHORT TERM...NED
LONG TERM...NED
AVIATION...ARK
FIRE WEATHER...NED
Area Forecast Discussion
National Weather Service Spokane WA
348 AM PST SUN JAN 4 2015
.SYNOPSIS...
A strong winter storm system has arrived and will last through Monday.
There is the potential of heavy mountain and valley snows, and a wintry
mix of sleet and freezing rain moving from south to north across
the Inland Northwest. Expect a trend toward drier and warmer
weather by the middle of next week.
&&
.DISCUSSION...
***SIGNIFICANT WINTER STORM TODAY INTO MONDAY***
Today and tonight: With the first round of stratiform snow expanding
slowly in areal coverage and intensity, there are already some
issues with model guidance as far initialization of this
snow...with most solutions a bit too far north based on both the
radar and sfc obs. The RAP qualitatively is doing the best the
last few hours, but it looks like by 12z-16z both the GFS and Nam
become more in alignment, with all guidance showing a marked
increase in snow chances later today as the low-level flow backs
and quickly enhances the isentropic ascent over the slow
northward-moving frontal sfc. We increased snow amnts a few tenths
on average for this morning based on the latest ground truth,
then adjusted by model guidance for later today and tonight. SWE
ratios should easily be about 15 to 1 for liquid conversion in the
lower elevations. The 850mb flow increases dramatically by early
this evening, which is when the fcst becomes very challenging. We
still expect to see a surge of 40kt SW winds about 5k ft msl over
the Palouse and into N Idaho and Spokane that will quickly
produce rising snow levels that will result in a rapid transition
from snow to rain (with pockets of sleet and/or freezing rain)
for a large part of Ern Wa and N Idaho. The zones along the BC
border will be the last to eventually make this transition,
resulting in the heaviest accumulations. The cold damming against
the E slopes of the Cascades will prolong moist frontal ascent,
but the depth of this ascent is not very deep as strongly veered
westerly winds strengthen aloft in the lee of the Cascades,
resulting in a lee shadow (not zero pcpn, but much less than
points east. bz
Monday and Tuesday: High pressure will begin building east toward the
WA Coast and eventually to the Cascades Tuesday. A moist laden
frontal boundary will remain draped on the eastern periphery of
the ridge...generally in a NW to SE orientation through
Northeastern WA and Northern ID. South of this boundary, strong
west to southwest orographic flow will hammer the Cascade Crest,
Idaho Panhandle Mtns, and Blue Mtns with moderate to heavy
precipitation. Along and north of the boundary, a combination of
low-level convergence, isentropic ascent, and frontogenetical
forcing will keep precip chances high. The Basin and lee of the
Cascades will carry the lowest precip chances due to a rain
shadow. The overall movement of the frontal boundary will be
toward the east as the ridge builds inland but this will not be a
smooth ride as several features dropping down the Divide oppose
its eastward progression. Consequently, there are signs with this
evening`s guidance that the front stalls over NE WA and Nrn ID
through much of this period. If this was to occur, precip will
remain all snow..falling light to moderate, with emphasis north of
a line from Republic to Spirit Lake. South of this line, it
appears likely that the warmer air will dominate leading to a mix
of valley rain/snow and mountain snow.
The first opposition will be the remnants of a shortwave currently
over the Gulf of AK. This will usher a reinforcing shot of cooler
yet drier air down the Continental Divide Monday
morning/afternoon. Strong SW winds initiating Sunday night will
weaken and possibly swing around to the N/NE for locations from
Omak to Deer Park to Rathdrum and points north. While this will
also bring in some relatively drier air...it will also bring a
brief reinforcement of cooler air and keep the tongue of warmer
air from surging northward allowing precip north of this line to
remain mainly snow. There is some uncertainty how strong the NE
push will be and if the northeast push was stronger than forecast,
this may occur further south and the opposite holds true in the
other direction. South of this line, it looks as if the warm air
will hold strong and keep lowland precip in the form of rain.
The second opposition arrives Tuesday morning in the form of a
second surge of arctic air dropping south east of the Continental
Divide. This once again stalls the moist laden frontal boundary
from lifting east and continues to focus precip across far
northeastern WA and northern Idaho from Republic to Kellogg and
points north until the boundary finally loses it source of
moisture and fizzles out Tuesday evening. Models show decent
agreement with this feature and suggest snow to continue for
Boundary County into far northeastern WA including locations like
Metaline Falls, Ione, and Northport.
* Changes To Previous Forecast: Overall changes to the previous forecast
include keeping snow levels lower for an extended period of time
across Boundary, northern Pend Oreille, and northern
Stevens/Ferry Counties. Bufkit data and Max wetbulb temperatures
within the 0-4km layer would support this idea and if these far
northern valleys remain snow for the entire event, it is
conceivable that another 3-7 inches of snow falls Monday and
Tuesday.
I also increased mountain snow amounts for the Central Panhandle
Mtns Monday morning as snow levels rise from 3000-5000 feet. With
strong omega at the time, these are the times when snow rates of
2-3 inches/hr have been observed and snow ratios have been
increased
* Snow levels: near valley floors north of Rathdrum to Republic
starting off Monday morning and rising slowly. South of this
line, valleys will be all rain. In Idaho, snow levels starting
off 3-4K ft AGL...rising 4-6K ft AGL by Tuesday. In the
Cascades, increasing 5-7K ft AGL.
* Impacts: Snow will continue to impact travel over Lookout Pass
Monday morning before switching over to rain Monday afternoon.
Light snow could impact travel along Highway 20 and Sherman Pass
through Tuesday and the communities of Bonners Ferry, Priest
Lake, Metaline Falls, Laurier, and Ione.
Rain on snow could bring the potential for moderate slush which could
lead to challenging travel conditions, especially on hills and
untreated roads.
*Confidence Levels: High for additional precipitation in the
mountains due to orographic lift. Lower exactly where the
frontal boundary stalls and its impacts to snow levels and
amounts in the valleys near the Canadian Border.
Wednesday through Thursday afternoon: A strong upper-level ridge of
high pressure will regain control of the region`s weather pattern
delivering dry conditions. Subsidence associated with the ridge
will promote strengthening low-level inversions and likelihood for
widespread fog and low clouds. Temperature forecasting will be
quite the challenge and carry low confidence. The warmest
temperatures should be in the mountains with temperatures
2000-4000 feet off the ground warming into the 40`s while valleys
remain in the 20s to 30s. /sb
Thursday night through Sunday: As ridge flattens, another trof of
moisture flows into the region from the Northwest. The models are
in fairly good agreement on the timing. The main impact areas will
be the Cascades and the Idaho Panhandle as orographic lift will
help enhance development of showers. An occasional rain shower is
possible in the Columbia Basin. Precip is expected to snow for the
high elevations in the mountains and rain showers for the lower
elevations with an occasional mixed precip during the overnight
hours along the Northern Columbia Basin. This is do to the higher
than normal temperatures across the region and the lack of
nocturnal cooling do to high amount of cloud cover. Temperatures
will range upper 30s to low 40s for the high and upper 20s to low
30s for the lows. /JDC
&&
.AVIATION...
12Z...Strong and moist ascent along a slow moving warm front will
promote IFR conditions at times today for most TAF sites across
Ern Wa and N Idaho through 00z Monday. After 00Z there may be a
change from -SN to -FZRA. Highest confidence in FZRA is for KMWH
and KEAT. Lower confidence in changeover at KLWS/KPUW. The KGEG-
KCOE sites should remain in -SN through 06Z. LLWS will be a
concern at all TAF sites after 03Z Monday.
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 29 29 39 34 39 27 / 100 100 80 60 20 10
Coeur d`Alene 29 29 37 35 39 25 / 100 100 100 90 50 10
Pullman 32 32 44 38 43 32 / 100 100 100 60 20 0
Lewiston 37 36 48 40 47 35 / 100 100 60 40 10 0
Colville 26 25 34 32 35 27 / 100 100 80 70 50 20
Sandpoint 25 23 35 32 35 23 / 100 100 90 90 80 30
Kellogg 27 27 35 34 37 26 / 100 100 100 100 60 20
Moses Lake 31 29 42 35 43 32 / 90 80 40 20 10 0
Wenatchee 29 29 44 36 42 35 / 90 80 50 20 10 0
Omak 28 25 37 32 39 30 / 100 90 50 50 10 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning from 7 AM this morning to 4 PM PST Monday
for Northern Panhandle.
Winter Storm Warning from 7 AM this morning to 4 AM PST Monday
for Coeur d`Alene Area-Idaho Palouse.
Winter Weather Advisory from 7 AM this morning to 4 AM PST
Monday for Lewis and Southern Nez Perce Counties.
Winter Storm Warning from 7 AM this morning to 4 AM PST Tuesday
for Central Panhandle Mountains.
WA...Winter Storm Warning from 7 AM this morning to 4 PM PST Monday
for Northeast Mountains-Okanogan Highlands.
Winter Storm Warning from 7 AM this morning to 4 AM PST Monday
for Northeast Blue Mountains-Okanogan Valley-Spokane Area-
Washington Palouse.
Winter Weather Advisory from 7 AM this morning to 4 AM PST
Monday for Moses Lake Area-Upper Columbia Basin-Waterville
Plateau-Wenatchee Area.
Winter Storm Warning until 4 AM PST Monday for East Slopes
Northern Cascades.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
518 AM CST SUN JAN 4 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 309 AM CST SUN JAN 4 2015
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A NORTHERN STREAM TROUGH OVER SOUTH CENTRAL CANADA INTO NORTH
DAKOTA...A SOUTHERN STREAM TROUGH FROM THE CENTRAL PLAINS INTO
ILLINOIS..AND RIDGES ON BOTH COASTS OF THE U.S.. ALSO OF NOTE WERE A
POTENT SHORTWAVE IN MO AND IL WITH A WEAKER SHORTWAVE MOVING THROUGH
THE FORECAST AREA. THIS LATTER SHORTWAVE IN CONJUNCTION WITH MID
LEVEL FRONTOGENESIS HAS SUPPORTED A BAND OF SNOW ACROSS MUCH OF THE
FORECAST AREA. SEE THE LATEST MKEPNSARX FOR UPDATED SNOWFALL
AMOUNTS THROUGH THE MORNING. ANY PRECIPITATION WITH THE POTENT
SHORTWAVE HAS STAYED SOUTH OF THE FORECAST AREA. HOWEVER...WE ARE
FEELING ITS EFFECTS IN THE WIND DEPARTMENT...AS THAT POTENT
SHORTWAVE HAS HELPED TO DEEPEN A SURFACE LOW NOW OVER LOWER MI.
NORTHWEST WINDS HAVE BEEN GUSTING IN THE 20-40 MPH RANGE...HIGHEST
WEST OF U.S. HIGHWAY 52. THESE WINDS ARE ADVECTING ARCTIC AIR INTO
THE REGION FROM THE NORTHERN STREAM UPPER TROUGH IN SOUTH CENTRAL
CANADA. 925MB TEMPS PER RAP ANALYSIS HAVE FALLEN TO -5C SOUTHEAST
TO -15C NORTHWEST ACROSS THE FORECAST AREA...WITH SURFACE
TEMPERATURES FROM THE MID TEENS SOUTHEAST TO UPPER SINGLE DIGITS
NORTHWEST. MEANWHILE...MUCH COLDER -20 TO -24C 925MB AIR WAS
LURKING ACROSS THE EASTERN DAKOTAS AND WESTERN MN...AND AROUND
-30C UNDER THE UPPER TROUGH. READINGS ARE WELL BELOW ZERO UNDER
THIS COLDER AIR.
THE MID LEVEL FRONTOGENETICAL BAND OF SNOW CURRENTLY OVER THE
FORECAST AREA SHOULD MOVE OFF TO THE EAST QUICKLY THIS MORNING...IN
RESPONSE TO THE SHORTWAVE OVER THE AREA MARCHING EAST. MOST MODEL
GUIDANCE SUGGESTS BY 15Z THE SNOW SHOULD HAVE PUSHED OFF TO THE
EAST...WITH MAYBE SOME LINGERING FLURRIES OVER WI UNTIL 18Z. THE
REST OF THE SHORT TERM PERIOD IS DRY AS SUBSIDENCE AND DRY ARCTIC
AIR MOVE IN.
ATTENTION THEN TURNS TO TEMPERATURES/WIND CHILLS AS ARCTIC AIR POURS
INTO THE REGION...IN RESPONSE TO THE UPPER TROUGH OVER SOUTH CENTRAL
CANADA CROSSING THE FORECAST AREA. 925MB TEMPS FALL TO -20 TO -24C
BY 00Z AND -23 TO -27C BY 12Z MONDAY. THIS ADVECTION OF ARCTIC AIR
COMBINED WITH A 15 TO 25 MPH SUSTAINED WIND SPEED TODAY CAUSES WIND
CHILLS TO EVENTUALLY FALL INTO ADVISORY CRITERIA / LESS THAN 20
BELOW ZERO / EVERYWHERE BY SUNSET. FURTHER COOLING TAKES PLACE
TONIGHT TO PUT TAYLOR AND CLARK INTO WARNING CRITERIA / 35 BELOW
ZERO. PORTIONS OF SOUTHEAST MN COULD GET CLOSE TO WARNING AS
WELL.
REGARDING HAZARDS. CONSIDERED WAITING UNTIL 15Z...THE EXPIRATION
TIME OF THE WINTER WEATHER ADVISORY FOR OUR WESTERN 10 COUNTIES...TO
START HOISTING THE WIND CHILL ADVISORIES. HOWEVER...GIVEN THE REST
OF THE FORECAST AREA IS SEEING WIND CHILL ADVISORY CRITERIA
TODAY...AND ALL NEIGHBORING FORECAST OFFICES ALSO HOISTING
ADVISORIES...HAVE ISSUED THE ADVISORIES NOW. HAVE ALSO UPGRADED THE
WATCH FOR TAYLOR/CLARK TO A WARNING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 309 AM CST SUN JAN 4 2015
THE ARCTIC AIR OVER THE REGION TO START MONDAY MODIFIES QUITE A BIT
THROUGH THE DAY...REFLECTED BY 925MB TEMPS CLIMBING TO -18 TO -21C
BY 00Z. THIS MODIFICATION ALLOWS OUR WIND CHILLS TO MOSTLY GET ABOVE
ADVISORY CRITERIA BY 18Z...WHICH IS THE END TIME FOR THE HAZARDS.
SOME EXTENSION PAST 18Z COULD BE REQUIRED FOR A FEW AREAS.
HOWEVER...THE IMPROVEMENT IN WIND CHILLS COMES AT THE EXPENSE OF
SNOW MOVING INTO THE REGION DURING THE AFTERNOON.
04.00Z MODEL GUIDANCE CONTINUES TO DEPICT A FAST MOVING POTENT
SHORTWAVE...CURRENTLY IN THE GULF OF ALASKA...TRACKING FROM CENTRAL
MONTANA AT 18Z MONDAY TO EASTERN IOWA BY 06Z TUESDAY. THIS IS A
DISTANCE OF 925 MILES...RESULTING IN A 77 MPH AVERAGE SPEED FOR THE
SHORTWAVE. THE COMBINATION OF DPVA FROM THE SHORTWAVE...DIVERGENCE
FROM THE LEFT EXIT REGION OF AN UPPER JET AND STRONG MID LEVEL
FRONTOGENESIS...WILL LEAD TO A BROAD SWATH OF SNOW ON THE ORDER OF
300 MILE WIDTH. CONTAINED WITHIN THAT SWATH WILL BE A SMALLER...
HEAVIER BAND ON THE ORDER OF 100 MILE WIDTH PER MODEL CONSENSUS.
LIQUID EQUIVALENT AMOUNTS COULD BE AS HIGH AS 0.5 INCH AS SUGGESTED
BY THE NAM/GFS AND SOME SREF MEMBERS. WITH A DEEP EFFECTIVE
DENDRITIC GROWTH OF 300MB...THAT COULD RESULT IN 8 TO 12 INCHES OF
SNOWFALL...MUCH OF WHICH FALLING WITHIN IN A 9 HOUR WINDOW. THE
SERIOUS PROBLEM IN FORECASTING THESE HIGH AMOUNTS IS PLACEMENT. THE
BOUNDS SEEMS TO BE THE SOUTHERN PORTION OF THE FORECAST AREA PER THE
04.00Z NAM AND ALONG I-80 PER THE 04.00Z GFS. GIVEN THIS LARGE
PLACEMENT ISSUE...CANNOT FORECAST THE HIGHER AMOUNTS YET.
HOWEVER...THE WINTER STORM WATCH IS VERY MUCH WARRANTED...THOUGH
LATER SHIFTS MAY BE ABLE TO TRIM OFF THE NORTHERN SIDE OF THE WATCH.
REGARDING PRECIPITATION CHANCES...HAVE INCREASED THEM QUITE A BIT
FOR MONDAY AFTERNOON GIVEN FASTER TIMING...ALONG WITH MORE OF A
DECREASE FOR OVERNIGHT MONDAY NIGHT.
ATTENTION THEN TURNS BACK TO THE ARCTIC COLD AS A SHORTWAVE TROUGH
CURRENTLY OVER BAFFIN ISLAND DROPS SOUTH ACROSS THE AREA TUESDAY
NIGHT AND WEDNESDAY. THIS SHOT OF ARCTIC AIR LOOKS NASTY AS 925MB
TEMPS FALL FROM -14C TO -18C AT 12Z TUESDAY...TO -18 TO -21C AT 00Z
WEDNESDAY...TO -26C TO -28C BY 12Z WEDNESDAY AND HOLDING IN THE -24
TO -28C RANGE FOR MUCH OF WEDNESDAY. TEMPERATURES SHOULD PLUMMET
WELL BELOW ZERO FOR TUESDAY NIGHT AND STAY BELOW ZERO ON WEDNESDAY.
IN FACT...MEX GUIDANCE SUGGESTS SOME LOCATIONS ON WEDNESDAY MAY NOT
CLIMB ABOVE -10. ADD INTO THIS A BRISK NORTHWEST WIND INDUCED BY
925MB WINDS IN THE 35-45 KT RANGE COMING ACROSS TUESDAY NIGHT AND
WEDNESDAY...THIS IS A PERFECT RECIPE FOR WIND CHILLS TO DROP TO NEAR
OR INTO WARNING CRITERIA EVERYWHERE. IT MAY NOT BE UNTIL SOMETIME
THURSDAY WHEN WE FINALLY GET OUT OF ADVISORY CRITERIA.
A BRIEF WARM UP IS PROGGED THURSDAY IN RESPONSE TO WARM ADVECTION
AHEAD OF ANOTHER POTENT SHORTWAVE DROPPING SOUTH INTO MN. THIS WARM
ADVECTION LOOKS TO INDUCE SOME LIGHT SNOW OVER THE NORTHEAST HALF OF
THE FORECAST AREA. HAVE RAISED PRECIPITATION CHANCES TO 30-40 AND
MAY NEED FURTHER INCREASES. IN THE WAKE OF THE SHORTWAVE...ANOTHER
ARCTIC AIRMASS DROPS IN...SIMILAR TO THE ONE FOR TONIGHT. MORE WIND
CHILL HEADLINES ARE LIKELY. FOLLOWED A MODEL CONSENSUS FOR HIGHS
FRIDAY AND LOWS THURSDAY NIGHT THROUGH FRIDAY NIGHT...BUT THESE MAY
NEED TO BE LOWERED 3-5 DEGREES.
AS WE HEAD INTO THE WEEKEND...THE HIGH LATITUDE BLOCKING PATTERN
ACROSS THE PACIFIC INTO WESTERN NORTH AMERICA FINALLY BREAKS DOWN.
THIS WILL ALLOW FOR A MODERATING TREND ACROSS THE FORECAST
AREA...GETTING TEMPERATURES BACK UP TO NEAR NORMAL BY MONDAY NEXT
WEEK. HOWEVER...IT APPEARS ACCOMPANYING THE WARM ADVECTION COULD BE
SOME LIGHT SNOW FOR LATE SATURDAY INTO SATURDAY NIGHT PER 04.00Z
ECMWF.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 518 AM CST SUN JAN 4 2015
LIGHT SNOW WILL GRADUALLY TAPER OFF AT THE TAF SITES THIS MORNING
BUT BEFORE IT DOES...IFR CONDITIONS ARE EXPECTED. SOME BLOWING
AND DRIFTING SNOW IS ALSO POSSIBLE AT KRST THROUGH LATE MORNING.
OTHERWISE PLAN ON GUSTY NORTHWEST WINDS OF 18 TO 23 KTS WITH
GUSTS TO AROUND 30 KTS POSSIBLE. THE SNOW WILL END LATER THIS
MORNING BUT THE GUSTY WINDS COULD CONTINUE TO PRODUCE BLOWING SNOW
AT KRST INTO EARLY THIS AFTERNOON. LOOK FOR SKIES TO CLEAR LATE
THIS AFTERNOON AND FOR WINDS TO DIMINISH TO INTO THE 9 TO 13 KT
RANGE TONIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WIND CHILL ADVISORY FROM 9 AM THIS MORNING TO NOON CST MONDAY
FOR WIZ032>034.
WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO NOON CST MONDAY
FOR WIZ041>044-053.
WINTER STORM WATCH FROM MONDAY EVENING THROUGH LATE MONDAY NIGHT
FOR WIZ053>055-061.
WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO NOON CST MONDAY
FOR WIZ054-055-061.
WIND CHILL WARNING FROM 9 PM THIS EVENING TO NOON CST MONDAY FOR
WIZ017-029.
WIND CHILL ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS
EVENING FOR WIZ017-029.
MN...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY
NIGHT FOR MNZ086-087-094>096.
WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR MNZ086-
087-094-095.
WIND CHILL ADVISORY FROM 9 AM THIS MORNING TO NOON CST MONDAY
FOR MNZ079-086>088-094-095.
WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO NOON CST MONDAY
FOR MNZ096.
IA...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY
NIGHT FOR IAZ008>011-018-019-029-030.
WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR
IAZ008>010-018-019-029.
WIND CHILL ADVISORY FROM 9 AM THIS MORNING TO NOON CST MONDAY
FOR IAZ008-009-018-019.
WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO NOON CST MONDAY
FOR IAZ010-011-029.
WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO NOON CST MONDAY
FOR IAZ030.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS ALBANY NY
1244 PM EST SUN JAN 4 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE FROM THE EASTERN GREAT LAKES
REGION TO SOUTHERN QUEBEC TODAY. A STRONG COLD FRONT WILL MOVE
ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND LATE THIS AFTERNOON
INTO TONIGHT WITH RAIN SHOWERS TRANSITIONING TO SNOW SHOWERS.
BLUSTERY AND COLD CONDITIONS WILL OPEN THE WORK WEEK WITH LAKE
EFFECT SNOW SHOWERS MAINLY NORTH AND WEST OF THE GREATER CAPITAL
REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1230 PM EST...PER MESONET OBSERVATIONS...JUST A FEW MORE
SPOTS INTO PORTIONS OF EASTERN WINDHAM COUNTY AND NORTHERN WARREN
COUNTY WHERE TEMPERATURES WERE AT THE FREEZING MARK.
OTHERWISE...THE WARMING TREND CONTINUES AS THE SURFACE WARM FRONT
REMAINS JUST UPSTREAM OF OUR CWFA. CENTRAL NY OBS HAVE OBSERVED A
QUICK JUMP IN BOTH TEMPERATURES AND WINDS WITH MANY LOCATIONS INTO
THE 50S WITH SOUTHERLY WIND GUSTS OVER 20KTS. PER THE
RAP13/HRRR...SEEMS THIS WARM FRONT WILL GET PINCHED ALONG OUR
SOUTHERN AND SOUTHWESTERN CWA BORDER SO HAVE ADJUSTED TEMPS
SLIGHTLY DOWNWARD FOR THE BALANCE OF THE AFTERNOON HOURS.
OTHERWISE...COLD FRONT AND PREFRONTAL TROUGH NOW APPROACHING
WESTERN NY WILL LIKELY ASSIST WITH FOCUS FOR ADDITIONAL SHOWER
DEVELOPMENT LATER THIS AFTERNOON. IN ADDITION...A STRENGTHENING
MID LEVEL JET /GREATER THAN 100KTS @ H500/ IS EXPECTED TO OCCUR
ACROSS THE MID AND LOWER HUDSON RIVER VALLEY. THE AGEOSTROPHIC
RESPONSE WILL LIKELY RESULT IN A MORE ROBUST SHOWER DEVELOPMENT
FOR LOCATIONS SOUTH AND EAST OF ALBANY WHERE WE WILL PLACE HIGHER
POPS.
THE PREFRONTAL TROUGH WILL MOVE ACROSS THE REGION IN THE
LATE AFTERNOON AND THE COLD FRONT WILL APPROACH FOR THE EARLY
EVENING. THE LLJ AT H850 INCREASES TO 45-60 KTS AHEAD OF THE COLD
FRONT...AS THE SFC WAVE MOVES INTO SRN QUEBEC. THE CYCLONE DOES
DEEPEN TO CLOSE TO 990 HPA BY 00Z/MON. THE 6-HR PRESSURE FALLS ARE
EXPECTED TO BE OVER SE QUEBEC AND NRN NEW ENGLAND. THE H925 WINDS
AHEAD AND JUST BEHIND THE FRONT CONTINUE TO BE STRONG AT 30-40
KTS...BUT MIXING DOWN 40 KTS IN THE EARLY EVENING MAY BE
DIFFICULT. WE WILL CONTINUE TO HAVE SOME GUSTS TO 30 TO 40 WITH A
BURST OF SHOWERS WITH THE FRONT. EXPECT THE SHOWERS TO TRANSITION
TO SNOW SHOWERS ACROSS THE WRN DACKS IN THE EARLY EVENING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
...LAKE EFFECT SNOW ADVISORY ISSUED FROM 7 PM SUNDAY TO 7 AM
MONDAY FOR NORTHERN HERKIMER AND HAMILTON COUNTIES...
...LAKE EFFECT SNOW ADVISORY ISSUED FROM 4 AM MONDAY TO 7 PM
MONDAY FOR SOUTHERN HERKIMER...FULTON AND MONTGOMERY COUNTIES.
THE ADVISORIES ARE FOR SNOW AND BLOWING SNOW WITH GUSTY WINDS OF
35 TO 45 MPH.
OUR CONFIDENCE WAS NOT GREAT ENOUGH TO ISSUE A WIND ADVISORY FOR
PARTS OF THE REGION SUNDAY NIGHT...THOUGH A 3RD PERIOD ADVISORY
MAY BE NEEDED FOR MONDAY...AS BETTER MOMENTUM TRANSFER IS
EXPECTED...BUT FOR NOW WIDESPREAD 46-57 MPH WIND GUSTS ARE NOT
ANTICIPATED FOR SUNDAY NIGHT INTO MONDAY. THIS WILL CONTINUE TO BE
MONITORED.
TONIGHT...COLD FRONT MOVES ACROSS THE REGION WITH STRONG LOW LEVEL
COLD ADVECTION EXPECTED. WESTERLY UPSLOPE SNOW SHOWERS WILL
INITIALLY IMPACT THE WRN DACKS AND SRN GREENS MTNS WITH MORE SCT
RAIN AND SNOW SHOWER ACTIVITY AWAY FROM THESE AREAS.
THE LATEST HIRES WRF AND 3-KM HRRR INDICATE A TRANSITION FROM THE
WESTERLY UPSLOPE SNOW SHOWERS OVER THE WRN DACKS TO AN ORGANIZED
SINGLE BAND. BUFKIT PROFILES JUST DOWNSTREAM OF LAKE ONTARIO
INDICATED MODERATE INSTABILITY WITH AN INVERSION HEIGHT CLOSE TO
10 KFT. HOWEVER...THE BAND IS EXPECTED TO FORM AND QUICKLY
TRANSITION S/SE WITH THE STRONG VEERING WIND PROFILE IN THE
BOUNDARY LAYER. THE LOW LEVEL FLOW STARTS AT 260-270 DEGS AND THEN
SHIFTS TO A 280 TO 290 DEG LOW-LEVEL TRAJECTORY. A QUICK BLAST OF
HVY SNOW SHOWERS IS ANTICIPATED FOR THE WRN DACKS WITH 3 TO 6
INCHES OF SNOW WITH PERHAPS SOME 4 TO 8 INCH AMOUNTS JUST SOUTH OF
OLD FORGE AND INLET. THE TRANSITORY BAND MOVES INTO SRN HERKIMER
COUNTY...AND THE W-CNTRL MOHAWK VALLEY BTWN 4-7 AM. THE NAM AND
HIRES WRF SHOW A MULTI-LAKE CONNECTION WITH MDT INSTABILITY CLASS
AT KUCA BUFKIT PROFILE. THIS AREA MAY NEED AN UPGRADE LATER...BUT
WE PUT THE ENTIRE W-CNTRL MOHAWK VALLEY CORRIDOR WAS ALSO PLACED
IN A LAKE EFFECT SNOW ADVISORY FOR SNOW AND BLOWING SNOW. ADVISORY
WIND LEVEL GUSTS WILL BE CLOSE WITH 35 TO 45 MPH GUSTS FORECASTED.
LOWS WILL BE MUCH COLDER IN THE TEENS TO M20S WITH SOME SINGLE
DIGITS OVER THE ADIRONDACK PARK...AND U20S OVER THE MID HUDSON
VALLEY.
MONDAY...THE BETTER PRESSURE RISES PASS NORTH OF ST LAWRENCE RIVER
VALLEY AND NRN NY BTWN 12Z-18Z MON 8-10 HPA/6 HRS. THE ISALLOBARIC
COUPLET IS IMPRESSIVE AS THE CYCLONE DEEPENS AND INTENSIFIES TO
ABOUT 980 HPA OVER THE GULF OF ST LAWRENCE BY 12Z/MON. SOME
SUSTAINED WESTERLY WINDS OF 15 TO 25 MPH WITH GUSTS 35 TO 45 MPH
ARE EXPECTED. THE 10-M WINDS ON THE GFSMOS PRODUCT FOR KALB ARE
IMPRESSIVE IN THE 18-24 KT SUSTAINED RANGE. THE BUFKIT MOMENTUM
TRANSFER PROFILES SHOW 40 KTS WILL NEED TO MIXED FROM 2.5 KFT AGL
FOR WIND ADVISORY CRITERIA TO BE MET. ANY WIND FLAGS WILL BE
MONITORED BY LATER SHIFTS. IT DOES LOOK PLAUSIBLE THAT SOME LAKE
EFFECT SHOWERS MAY SNEAK DOWN THE MOHAWK RIVER VALLEY INTO THE
CAPITAL REGION AND NRN TACONICS. HIGH CHC AND LIKELY POPS WERE USED
LATE MONDAY MORNING INTO THE PM FOR A COATING TO PERHAPS A HALF AN
INCH OF SNOW. SOME OF THE UPSLOPE AREAS OF THE SRN GREENS IN THE
SRN VT...TACONICS...AND NRN BERKS COULD GET AN INCH OR TWO OR
SNOW. THE ADVISORY AREA HIGHLIGHTED WILL LIKELY RECEIVE 3 TO 6
INCHES WITH SOME ISOLATED 4 TO 8 INCH AMOUNTS. THE INVERSION
HEIGHTS DO LOWER IN THE AFTERNOON...AND THE SHEAR INCREASES SO THE
DOWNSTREAM TRAJECTORY WILL DECREASE. MAX TEMPS MAY BE IN THE
MORNING...AND TEMPS MAY CONTINUE TO FALL SLOWLY IN THE AFTERNOON
IN THE POTENT COLD ADVECTION REGIME...AS H850 TEMPS CRASH INTO THE
-17C TO -22C RANGE ACROSS THE FCST AREA. DAYTIME HIGHS WILL BE IN
THE M20S TO L30S FROM THE TRI CITIES SOUTH AND EAST...AND TEENS TO
L20S NORTH AND WEST WITH SOME SINGLE NUMBERS OVER THE SRN DACKS.
WIND CHILLS WILL RANGE FROM 10 BELOW TO 10 ABOVE ZERO.
MONDAY NIGHT...LAKE EFFECT SNOW BAND LIFTS BACK NORTHWARD...AS THE FLOW
BACKS WITH AN APPROACHING SHORT-WAVE/CLIPPER LOW FROM THE GREAT
LAKES REGION AND MIDWEST. HIGH PRESSURE BRIEFLY BUILDS IN FROM
QUEBEC WITH A VERY COLD NIGHT EXPECTED. THE WINDS SHOULD
DIMINISH...AND FRIGID TEMPS ARE ANTICIPATED WITH LOWS BELOW ZERO
OVER THE SRN DACKS...AND PARTS OF THE LAKE REGION REGION...AND
ZERO TO 10 ABOVE IN MOST OTHER LOCATIONS WITH SOME LOWER TEENS IN
THE CAPITAL DISTRICT AND MID HUDSON VALLEY.
CLOUDS WILL INCREASE IN THE FRIGID AIR MASS WITH THE BETTER CHANCE
FOR LIGHT SNOW AND SCT SNOW SHOWERS ON TUE.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
VERY COLD TEMPERATURES AND ACTIVE WEATHER THIS WEEK...WITH THE
COLDEST TEMPERATURES OF THE WINTER EXPECTED WEDNESDAY NIGHT AND
THURSDAY WITH LIFE-THREATENING WIND CHILLS POSSIBLE.
A QUICK MOVING NORTHERN STREAM CLIPPER SYSTEM WILL BRING A PERIOD OF
LIGHT SNOW TO THE AREA TUESDAY. THIS SYSTEM IS EXPECTED TO PASS OVER
THE OHIO VALLEY AND MOVE OFF THE DELMARVA. IT WILL HAVE LIMITED
MOISTURE BUT GOOD FORCING. LOOKING AT HIGH RATIO SNOWFALL. AT THIS
TIME EXPECT BELOW ADVISORY LEVEL ACCUMULATIONS. HIGHS WILL BE AROUND
10 DEGREES BELOW NORMAL.
THE NEXT QUICK MOVING LOW PRESSURE SYSTEM AND NORTHERN STREAM SHORT
WAVE WILL BE IN ITS HEELS. WILL HAVE CONTINUING CHANCES FOR SNOW
SHOWERS TUESDAY NIGHT WITH SOME LAKE EFFECT/ENHANCEMENT INTO THE
WESTERN ADIRONDACKS. EXPECT SNOW SHOWERS AND POSSIBLY SNOW SQUALLS
AS THE ARCTIC BOUNDARY APPROACHES AND MOVES THROUGH WEDNESDAY. THIS
SYSTEM/FRONT WILL BE THE ONE THAT OPENS THE DOOR TO THE ARCTIC
AIRMASS WITH ITS PASSAGE STRONG COLD AIR ADVECTION WILL BEGIN.
850 MB TEMPERATURES ARE MODELED TO DROP TO -25 TO -30 DEGREES
CELSIUS ACROSS THE FORECAST AREA WEDNESDAY NIGHT. SURFACE
TEMPERATURES ARE FORECAST TO PLUMMET RANGING FROM AROUND 1 DEGREES
TO AROUND 20 DEGREES BELOW ZERO...AROUND 20 DEGREES BELOW NORMAL. IN
ADDITION...THE PRESSURE GRADIENT ACROSS THE REGION WILL BE TIGHT
BETWEEN THE DEPARTING LOW PRESSURE SYSTEM AND AN ADVANCING HIGH
RESULTING IN BRISK AND GUSTY NORTHWEST WINDS. THE COMBINATION OF THE
BITTER TEMPERATURES AND BRISK WINDS WILL RESULT IN DANGEROUS TO
LIFE-THREATENING WIND CHILL VALUES WEDNESDAY NIGHT INTO THURSDAY
MORNING. WILL KEEP MENTION IN THE HAZARDOUS WEATHER OUTLOOK.
THURSDAY WILL BE A FRIGID DAY WITH SOME HIGHER PRESSURE BUILDING IN.
TEMPERATURES WILL REMAIN AROUND 20 DEGREES BELOW NORMAL. THE LAST
TIME IS WAS THIS COLD WAS BACK ON JANUARY 22 2014...THE HIGH
TEMPERATURE IN ALBANY WAS ONLY 9 DEGREES WITH A LOW OF 6 DEGREES
BELOW ZERO. LOOKING AT SIMILAR VALUES. WITH NORTHWEST FLOW ACROSS
THE GREAT LAKES WOULD EXPECT MULTI BANDS ACROSS CENTRAL NEW YORK
WHICH COULD MAY REACH INTO THE FAR WESTERN PORTION OF THE FORECAST
AREA.
YET ANOTHER NORTHERN STREAM SYSTEM WILL APPROACH LATE IN THE WEEK
BRINGING MORE CHANCES FOR SNOW SHOWERS TO THE AREA. TEMPERATURES
WILL MODERATE SOME IN THE SOUTHWEST FLOW AHEAD OF THE APPROACHING
SYSTEM HOWEVER THEY WILL REMAIN WELL BELOW NORMAL. THE COLDEST AIR
IS EXPECTED TO REMAIN TO OUR NORTH PASSING OVER EASTERN CANADA ITS
IN WAKE AS WE HEAD INTO THE WEEKEND. COULD BE LOOKING AT MORE LAKE
EFFECT IN THE WAKE OF THE SYSTEM.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
FLYING CONDITIONS ARE CURRENTLY LIFR AT ALL SITES. LOW CIGS AND LOW
VSBY DUE TO FOG/MIST ARE CURRENTLY IN PLACE. WINDS ARE GENERALLY
LIGHT...EXCEPT FOR KALB...WHERE A SOUTHERLY FLOW UP THE HUDSON
VALLEY HAS ALLOWED FOR WINDS TO BE AROUND 10 KTS.
AS A COLD FRONT APPROACHES FROM THE WEST...WINDS WILL PICK UP AT ALL
SITES. THIS WIND WILL ALLOW THE LOW VSBYS TO IMPROVE TOWARDS 6SM OR
HIGHER DUE TO MIXING...AND SOME OF THE LOWER CLOUDS SHOULD START TO
BREAK UP AS WELL. THERE MAY BE SOME SHOWERS WITH THIS BOUNDARY...ESP
FOR KPOU/KPSF...AS OUR LOCAL HIRESWRF SHOWS A LINE OF HEAVY RAIN
SHOWERS AFFECTING THOSE TERMINALS BETWEEN SUNSET AND 7 PM.
BEHIND THE COLD FRONT...SHOWERS WILL END AND FLYING CONDITIONS WILL
IMPROVE EVEN FURTHER...AS DRIER AIR WORKS INTO THE AREA FROM THE
WEST. WITH COLDER AIR WORKING ITS WAY IN...GOOD MIXING WILL ALLOW
FOR SOME STRONG WIND GUSTS...ESP BY MONDAY MORNING...WHEN GUST OVER
30 KTS WILL BE POSSIBLE FOR KALB/KPSF. FLYING CONDITIONS SHOULD BE
AT LEAST MVFR TONIGHT...AND LOOK TO BE VFR FOR ALL SITES ON MONDAY.
THERE IS A LOW CHC FOR SOME SNOW SHOWERS TO AFFECT KALB ON MONDAY
MORNING...AS LAKE EFFECT ACTIVITY COULD WORK ITS WAY DOWN THE MOHAWK
VALLEY IN THE LATE MORNING HOURS. FOR NOW...WILL JUST INCLUDE
VCSH...BUT IF THIS OCCURS...IT COULD HAVE AN IMPACT ON VSBYS/CIGS
FOR A BRIEF PERIOD OF TIME.
OUTLOOK...
MON NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUE: MODERATE OPERATIONAL IMPACT. LIKELY SN.
TUE NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
WED: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF SHSN.
WED NIGHT: LOW OPERATIONAL IMPACT. BREEZY.
THU: NO OPERATIONAL IMPACT. NO SIG WX.
THU NIGHT-FRI: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
&&
.HYDROLOGY...
A COMPLEX STORM SYSTEM WITH MODERATE TO HEAVY QPF WILL MOVE ACROSS
THE HSA THROUGH TODAY.
MOST AREAS ARE FORECAST TO RECEIVE 1-2 INCHES OF LIQUID
EQUIVALENT PRECIPITATION...WITH LOCALLY IN EXCESS OF TWO INCHES.
THIS WILL ALLOW FOR SIGNIFICANT RISES ON RIVERS AND STREAMS ON
SUNDAY...AS TEMPERATURES RISE ABOVE FREEZING BRIEFLY OVER THE
ENTIRE REGION.
ISOLATED MINOR FLOODING IS POSSIBLE AND PER COLLABORATION
YESTERDAY WITH THE NERFC...THE HSA POINTS THAT GOES ABOVE ACTION
STAGE ARE WILLIAMSTOWN /WILM3/...AND GRANVILLE /GVVN6/ AT THIS
TIME. SINCE THE POTENTIAL OF WIDESPREAD MINOR FLOODING IS NOT
EXPECTED...A FLOOD WATCH HAS NOT BEEN ISSUED AT THIS TIME.
LAKE EFFECT SNOWFALL WILL IMPACT LOCATIONS NORTH AND WEST OF THE
CAPITAL REGION TONIGHT THROUGH MONDAY IN THE WAKE OF A STRONG COLD
FRONT.
THEREAFTER...BITTER COLD WEATHER IS EXPECTED NEXT WEEK. SOME
FREEZE UP ICE JAMS ARE POSSIBLE ACROSS THE SOUTHWESTERN
ADIRONDACKS AND SOUTHERN VERMONT BY LATE IN THE WEEK.
OTHERWISE...ICE WILL LIKELY DEVELOP AND INCREASE ACROSS RIVERS
AND STREAMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...LAKE EFFECT SNOW ADVISORY FROM 4 AM TO 7 PM EST MONDAY FOR
NYZ038>040-082.
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST
MONDAY FOR NYZ032-033.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...FRUGIS/BGM/WASULA
SHORT TERM...WASULA
LONG TERM...IAA
AVIATION...IAA
HYDROLOGY...BGM/WASULA
FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1209 PM EST SUN JAN 4 2015
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE WEST TONIGHT AND PUSH THROUGH
LATE SUNDAY FOLLOWED BY DRY HIGH PRESSURE. A STRONGER COLD FRONT
WILL DROP THROUGH WEDNESDAY EVENING...THEN COLD HIGH PRESSURE WILL
BUILD OVER THE REGION INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
QUICK UPDATE TO INCLUDE RECENTLY ISSUED TORNADO WATCH 3...WHICH IS
IN EFFECT UNTIL 6 PM.
LATE THIS MORNING...THE FOCUS FOR TODAY/S FORECAST OBVIOUSLY
REVOLVES AROUND THE APPROACHING CONVECTIVE LINE...ITS TIMING...AND
THE POTENTIAL FOR SEVERE WEATHER. BASED ON CURRENT RADAR IMAGERY
AND REGIONAL SURFACE OBSERVATIONS...THE CONVECTIVE LINE IS WELL
OUTPACING THE ACTUAL COLD FRONT BY ABOUT 100-125 MILES AS IT NOW
RACES THROUGH CENTRAL AND SOUTH GEORGIA AND THE FLORIDA PANHANDLE.
THE RECENT RUNS OF THE HRRR SEEM TO HAVE THE BEST INITIALIZATION
OF THE BAND OF PRECIPITATION AND CONVECTION...SO ITS TIMING FOR
THE AFTERNOON HAS BEEN USED THE MOST FOR THE TIMING. BASED ON
THIS...THE CONVECTION WILL BEGIN TO IMPACT THE FAR WESTERN
ZONES...INCLUDING TATTNALL/CANDLER/JENKINS COUNTIES ABOUT 18Z.
THIS WOULD THEN PUT THE CONVECTION INTO THE AN AREA ALONG A LINE
INCLUDING THE SAVANNAH METRO NORTH TO AROUND ALLENDALE AROUND 20Z.
FINALLY...AND ALTHOUGH IT IS LESS CERTAIN...THE CHARLESTON AREA
CAN EXPECT TO SEE THE LINE (IN WHATEVER STATE IT IS IN) AROUND
22Z.
REGARDING THE SEVERE POTENTIAL...THIS IS A SITUATION WE ARE ALL
TOO FAMILIAR WITH. WE HAVE A NICE AND IMPRESSIVE AMBIENT WIND
FIELD DEFINED BY 0-3 KM SHEAR APPROACHING 40 KNOTS AND 0-6 KM
SHEAR ON THE ORDER OF 50-60 KNOTS. AS ALWAYS SEEMS TO BE THE CASE
THOUGH...THE PRIMARY QUESTION FOCUSES ON THE PRESENCE OF BUOYANCY.
DESPITE THE WIDESPREAD CLOUD COVER...WE STILL EXPECT TO SEE HIGH
TEMPERATURES REACH INTO THE MID TO UPPER 70S IN MOST AREAS THIS
AFTERNOON. RECENT VISIBLE SATELLITE IMAGERY DOES NOT PROVIDE MUCH
EVIDENCE FOR ANY SCATTERING OF CLOUD COVER AND LITTLE TO NO DIRECT
INSOLATION IS EXPECTED. RAP/HRRR SOUNDINGS DO SHOW A NOTABLE CAP
AT ABOUT 900 MB...BUT WHEN MODIFIED FOR A SURFACE TEMPERATURE IN
THE MID/UPPER 70S...IT APPEARS THAT THE CAP CAN BE OVERCOME. IF
THIS OCCURS...BOTH THE RAP/HRRR GIVE CAPE VALUES IN EXCESS OF 750
J/KG...WITH A LARGE AREA APPROACHING 1000 J/KG. SO...THE MODELS
WOULD SUGGEST THAT THE ENVIRONMENT WILL SUPPORT A LINEAR
CONVECTIVE SYSTEM WITH AT LEAST A LOW END RISK OF SEVERE WEATHER.
THE PRIMARY THREAT WILL BE DAMAGING WIND GUSTS...BUT AS WITH ANY
HIGH SHEAR/LOW CAPE ENVIRONMENT THERE WILL BE THE THREAT OF AN
ISOLATED WEAK TORNADO WITHIN BOWING SEGMENTS. THE MAIN AREA OF
CONCERN WILL BE SOUTHEAST GEORGIA WHERE THE WARMEST TEMPERATURES
ARE EXPECTED THE BEST POTENTIAL FOR DESTABILIZATION WILL RESIDE.
OTHER THAN THE SEVERE WEATHER...WINDS WILL BE GUSTY OUTSIDE OF THE
CONVECTION THANKS TO THE TIGHT PRESSURE GRADIENT AND INCREASING
LOW LEVEL WINDS. RECENT WEB CAM IMAGES SHOW THAT SEA FOG HAS
BECOME INCREASINGLY CONFINED TO THE SHELF WATERS AND HAS DRIFTED
OFF THE DIRECT BEACH AREAS.
LAKE WINDS...WITHIN THE WARM SECTOR THE POTENTIAL FOR 25 KNOT
SOUTH/SOUTHWEST WIND GUSTS APPEARS SUFFICIENT TO JUSTIFY MAINTAINING
THE LAKE WIND ADVISORY ALONG LAKE SHORES FOR LAKE MOULTRIE VALID
10 AM UNTIL 5 PM TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
TONIGHT...THE COLD FRONT WILL SHIFT OFFSHORE BY MIDNIGHT...FOLLOWED
BY WEAK BUT DRY HIGH PRESSURE THROUGH TUESDAY. BY DAYBREAK
MONDAY...COLD ADVECTION WILL PUSH TEMPERATURES INTO THE 40S AT
MOST LOCATIONS. CLOUDS WILL BEGIN TO SCATTER OUT FROM THE WEST
LATER TONIGHT.
THE UPPER LEVEL PATTERN BECOMES ZONAL MONDAY THROUGH WEDNESDAY.
DRY HIGH PRESSURE WILL SPREAD INTO THE SOUTHEAST UNITED STATES ON
MONDAY THOUGH MODEST WNW FLOW AROUND 850 MB WILL SUPPORT DOWNSLOPE
WARMING AND HIGHS NEAR 60.
THE SURFACE HIGH WILL SHIFT OFF THE MID-ATLANTIC COAST MONDAY NIGHT
WITH A BRIEF RETURN FLOW AND INCREASING WSW LOW-LEVEL WINDS. WARM
AIR ADVECTION ON TUESDAY AND MOSTLY SUNNY SKIES WILL ALLOW TEMPS TO
REBOUND INTO THE MIDDLE 60S.
BOUNDARY LAYER FLOW VEERS AROUND TO THE NW LATE TUESDAY NIGHT INTO
WEDNESDAY...THOUGH 20-25 KT OF WNW 850 MB FLOW WILL MAINTAIN SOME
ADIABATIC WARMING. WEDNESDAY HIGH TEMPS WILL BE IN THE MID/UPPER 50S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A DIGGING LONGWAVE TROUGH SHIFTS THROUGH THE AREA WEDNESDAY NIGHT
AND THURSDAY WITH A STRONG COLD FRONT DROPPING THROUGH THE AREA
WEDNESDAY EVENING. IMPRESSIVE COLD AIR ADVECTION WILL ENSUE AS A
VERY DRY HIGH PRESSURE AIRMASS DROPS SOUTHEAST. THE ECMWF HAS
GENERALLY BEEN THE COLDER OF THE MODELS WITH THIS SYSTEM...THOUGH IT
HAS MODERATED SOMEWHAT IN RECENT RUNS. NEVERTHELESS...A COLD 36 HRS
IS IN STORE. THURSDAY MORNING WILL LIKELY DROP INTO THE LOWER TO
MIDDLE 20S...COINCIDENT WITH 15-20 KT WINDS. OUR LATEST APPARENT
TEMPERATURE GRIDS SHOW THE POTENTIAL FOR WIND CHILL ADVISORY
CRITERIA FOR A FEW HOURS LATE WEDNESDAY NIGHT. IT IS WORTH NOTING
THAT OUR CRITERIA FOR ISSUING WIND CHILL ADVISORIES INCREASED ON
DECEMBER 1ST 2014. THE NEW CRITERIA IS 15 DEGREES IN COASTAL
LOCATIONS OR 10 DEGREES INLAND. WE WILL ADD MENTION TO THE HAZARDOUS
WEATHER OUTLOOK.
STRONG COLD ADVECTION CONTINUING ON THURSDAY WILL YIELD BLUSTERY
CONDITIONS. BASED ON THE LATEST THICKNESS PROGS WE LOWERED HIGHS TO
THE UPPER 30S NORTH TO LOWER 40S SOUTH. THURSDAY NIGHT WILL AGAIN BE
COLD AS HIGH PRESSURE REMAINS TO THE WEST. THERE WERE EARLIER
INDICATIONS THAT THE BOUNDARY LAYER COULD DECOUPLE AND ALLOW FOR LOW
TEMPS IN THE TEENS. MORE RECENT MODEL RUNS SHOW A WEAK SHORTWAVE
MOVING THROUGH OVERNIGHT WITH STRENGTHENING 850 MB WINDS PREVENTING
SURFACE WINDS FROM GOING CALM. WE MAINTAINED LOW TEMPS IN THE LOW TO
MID 20S.
THE UPPER LEVEL PATTERN TRANSITIONS TO A BROAD TROUGH ACROSS THE
CENTRAL UNITED STATES FRIDAY INTO THE WEEKEND WITH THE SURFACE HIGH
EVENTUALLY MOVING INTO THE NORTHEAST STATES. MOISTURE WILL BEGIN TO
INCREASE LATE IN THE WEEKEND WITH INCREASING CLOUDS AND POSSIBLE
RAIN SHOWERS SATURDAY NIGHT AND SUNDAY. TEMPS WILL REMAIN BELOW
NORMAL BUT HIGHS WILL GENERALLY BE IN THE 50S.
&&
.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
MVFR THIS AFTERNOON BEFORE A BIT OF A BREAK OUT PRIOR TO BANDS OF
CONVECTIVE RAINS REACH THE TERMINALS AFTER MID AFTERNOON. SURFACE
WINDS WILL BE GUSTY AHEAD OF THE RAINS WITH GUSTS TOPPING 25 KT AT
KCHS AND 20 KT AT KSAV. THE COLD FRONT WILL MOVE OFF THE COAST
THIS EVENING WITH CONDITIONS FAVORING VFR TONIGHT IN THE WAKE OF
THE FRONT.
EXTENDED AVIATION OUTLOOK...VFR.
&&
.MARINE...
LATE THIS MORNING...BASED ON RECENT WEB CAMS AND CHARLESTON HARBOR
PILOT BOAT REPORTS HAVE OPTED TO EXTEND THE DENSE FOG ADVISORY
THROUGH 6PM.
THE COOL STABLE NEAR SHORE WATERS TYPIFIED BY THE 5-7 KT OF WIND
OVERNIGHT AT GRAYS REEF WHILE TEMPS REACHING THE MID 60S ALONG
THE GEORGIA COAST SUPPORTIVE OF 15 KT WINDS WITH THE STRONGEST FLOW
RELEGATED TO WARMER WATERS OFFSHORE. THE SMALL CRAFT ADVISORIES IN
OUR NEAR SHORE WATERS WILL BE MARGINAL TODAY ONCE YOU GET AWAY
FROM THE LAND/SEA INTERFACE BUT WE MAINTAINED 4-6 FT SEAS TO
KEEP PERSISTENCE. THE HIGHEST SEAS IN NEAR SHORE LEGS SHOULD OCCUR
ACROSS THE NORTHEAST PART OF AMZ350. THE CHARLESTON HARBOR WILL
BE GUSTY AT TIMES TODAY...ESPECIALLY THE UPPER REACHES WHERE THE
WARMER SURFACE TEMPS OCCUR. THE FRONT WILL MOVE OFFSHORE LATER
TONIGHT WITH SOME JETTING OF THE W AND NW FLOW OFF THE GEORGIA
COAST. WE BUMPED UP WINDS A BIT FROM GRAYS REEF SEAWARD TO TREND.
WINDS/SEAS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA MONDAY
THROUGH WEDNESDAY. CONDITIONS QUICKLY DETERIORATE WEDNESDAY EVENING
BEHIND A STRONG COLD FRONT. STRONG LOW-LEVEL WINDS AND COLD AIR
ADVECTION WILL YIELD WINDS TURNING AROUND TO THE NORTH AND
INCREASING TO 25-30 KT. FREQUENT 35 KT GUSTS ARE INCREASINGLY
LIKELY WEDNESDAY NIGHT INTO THURSDAY MORNING ACROSS THE WARMER
WATERS BEYOND ABOUT 15 NM FROM SHORE. A PERIOD OF GALE
WATCHES/WARNINGS IS LIKELY FOR PORTIONS OF THE WATERS DURING THIS
TIME.
CONDITIONS QUICKLY IMPROVE LATER THURSDAY INTO THE WEEKEND AS THE
HIGH PRESSURE SYSTEM WEAKENS AND EVENTUALLY SHIFTS NORTHEAST.
&&
.CLIMATE...
RECORD HIGH TEMPERATURES JAN 4...
CHS 77/2005 AND PREVIOUS...
CXM 75/1955...
SAV 80/2004...
RECORD HIGH MINIMUM TEMPERATURES JAN 4...
CHS 58/1950 AND PREVIOUS...
CXM 61/2007...
SAV 60/2004 AND PREVIOUS...
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...LAKE WIND ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR SCZ045.
MARINE...DENSE FOG ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ330-350-
352-354.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR AMZ352.
SMALL CRAFT ADVISORY UNTIL 5 AM EST MONDAY FOR AMZ350.
SMALL CRAFT ADVISORY UNTIL 11 AM EST MONDAY FOR AMZ374.
SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR AMZ330.
&&
$$
NEAR TERM...BSH
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...JRL
CLIMATE...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1135 AM EST SUN JAN 4 2015
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE WEST TONIGHT AND PUSH THROUGH
LATE SUNDAY FOLLOWED BY DRY HIGH PRESSURE. A STRONGER COLD FRONT
WILL DROP THROUGH WEDNESDAY EVENING...THEN COLD HIGH PRESSURE WILL
BUILD OVER THE REGION INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATE THIS MORNING...THE FOCUS FOR TODAY/S FORECAST OBVIOUSLY
REVOLVES AROUND THE APPROACHING CONVECTIVE LINE...ITS TIMING...AND
THE POTENTIAL FOR SEVERE WEATHER. BASED ON CURRENT RADAR IMAGERY
AND REGIONAL SURFACE OBSERVATIONS...THE CONVECTIVE LINE IS WELL
OUTPACING THE ACTUAL COLD FRONT BY ABOUT 100-125 MILES AS IT NOW
RACES THROUGH CENTRAL AND SOUTH GEORGIA AND THE FLORIDA PANHANDLE.
THE RECENT RUNS OF THE HRRR SEEM TO HAVE THE BEST INITIALIZATION
OF THE BAND OF PRECIPITATION AND CONVECTION...SO ITS TIMING FOR
THE AFTERNOON HAS BEEN USED THE MOST FOR THE TIMING. BASED ON
THIS...THE CONVECTION WILL BEGIN TO IMPACT THE FAR WESTERN
ZONES...INCLUDING TATTNALL/CANDLER/JENKINS COUNTIES ABOUT 18Z.
THIS WOULD THEN PUT THE CONVECTION INTO THE AN AREA ALONG A LINE
INCLUDING THE SAVANNAH METRO NORTH TO AROUND ALLENDALE AROUND 20Z.
FINALLY...AND ALTHOUGH IT IS LESS CERTAIN...THE CHARLESTON AREA
CAN EXPECT TO SEE THE LINE (IN WHATEVER STATE IT IS IN) AROUND
22Z.
REGARDING THE SEVERE POTENTIAL...THIS IS A SITUATION WE ARE ALL
TOO FAMILIAR WITH. WE HAVE A NICE AND IMPRESSIVE AMBIENT WIND
FIELD DEFINED BY 0-3 KM SHEAR APPROACHING 40 KNOTS AND 0-6 KM
SHEAR ON THE ORDER OF 50-60 KNOTS. AS ALWAYS SEEMS TO BE THE CASE
THOUGH...THE PRIMARY QUESTION FOCUSES ON THE PRESENCE OF BUOYANCY.
DESPITE THE WIDESPREAD CLOUD COVER...WE STILL EXPECT TO SEE HIGH
TEMPERATURES REACH INTO THE MID TO UPPER 70S IN MOST AREAS THIS
AFTERNOON. RECENT VISIBLE SATELLITE IMAGERY DOES NOT PROVIDE MUCH
EVIDENCE FOR ANY SCATTERING OF CLOUD COVER AND LITTLE TO NO DIRECT
INSOLATION IS EXPECTED. RAP/HRRR SOUNDINGS DO SHOW A NOTABLE CAP
AT ABOUT 900 MB...BUT WHEN MODIFIED FOR A SURFACE TEMPERATURE IN
THE MID/UPPER 70S...IT APPEARS THAT THE CAP CAN BE OVERCOME. IF
THIS OCCURS...BOTH THE RAP/HRRR GIVE CAPE VALUES IN EXCESS OF 750
J/KG...WITH A LARGE AREA APPROACHING 1000 J/KG. SO...THE MODELS
WOULD SUGGEST THAT THE ENVIRONMENT WILL SUPPORT A LINEAR
CONVECTIVE SYSTEM WITH AT LEAST A LOW END RISK OF SEVERE WEATHER.
THE PRIMARY THREAT WILL BE DAMAGING WIND GUSTS...BUT AS WITH ANY
HIGH SHEAR/LOW CAPE ENVIRONMENT THERE WILL BE THE THREAT OF AN
ISOLATED WEAK TORNADO WITHIN BOWING SEGMENTS. THE MAIN AREA OF
CONCERN WILL BE SOUTHEAST GEORGIA WHERE THE WARMEST TEMPERATURES
ARE EXPECTED THE BEST POTENTIAL FOR DESTABILIZATION WILL RESIDE.
OTHER THAN THE SEVERE WEATHER...WINDS WILL BE GUSTY OUTSIDE OF THE
CONVECTION THANKS TO THE TIGHT PRESSURE GRADIENT AND INCREASING
LOW LEVEL WINDS. RECENT WEB CAM IMAGES SHOW THAT SEA FOG HAS
BECOME INCREASINGLY CONFINED TO THE SHELF WATERS AND HAS DRIFTED
OFF THE DIRECT BEACH AREAS.
LAKE WINDS...WITHIN THE WARM SECTOR THE POTENTIAL FOR 25 KNOT
SOUTH/SOUTHWEST WIND GUSTS APPEARS SUFFICIENT TO JUSTIFY MAINTAINING
THE LAKE WIND ADVISORY ALONG LAKE SHORES FOR LAKE MOULTRIE VALID
10 AM UNTIL 5 PM TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
TONIGHT...THE COLD FRONT WILL SHIFT OFFSHORE BY MIDNIGHT...FOLLOWED
BY WEAK BUT DRY HIGH PRESSURE THROUGH TUESDAY. BY DAYBREAK
MONDAY...COLD ADVECTION WILL PUSH TEMPERATURES INTO THE 40S AT
MOST LOCATIONS. CLOUDS WILL BEGIN TO SCATTER OUT FROM THE WEST
LATER TONIGHT.
THE UPPER LEVEL PATTERN BECOMES ZONAL MONDAY THROUGH WEDNESDAY.
DRY HIGH PRESSURE WILL SPREAD INTO THE SOUTHEAST UNITED STATES ON
MONDAY THOUGH MODEST WNW FLOW AROUND 850 MB WILL SUPPORT DOWNSLOPE
WARMING AND HIGHS NEAR 60.
THE SURFACE HIGH WILL SHIFT OFF THE MID-ATLANTIC COAST MONDAY NIGHT
WITH A BRIEF RETURN FLOW AND INCREASING WSW LOW-LEVEL WINDS. WARM
AIR ADVECTION ON TUESDAY AND MOSTLY SUNNY SKIES WILL ALLOW TEMPS TO
REBOUND INTO THE MIDDLE 60S.
BOUNDARY LAYER FLOW VEERS AROUND TO THE NW LATE TUESDAY NIGHT INTO
WEDNESDAY...THOUGH 20-25 KT OF WNW 850 MB FLOW WILL MAINTAIN SOME
ADIABATIC WARMING. WEDNESDAY HIGH TEMPS WILL BE IN THE MID/UPPER 50S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
A DIGGING LONGWAVE TROUGH SHIFTS THROUGH THE AREA WEDNESDAY NIGHT
AND THURSDAY WITH A STRONG COLD FRONT DROPPING THROUGH THE AREA
WEDNESDAY EVENING. IMPRESSIVE COLD AIR ADVECTION WILL ENSUE AS A
VERY DRY HIGH PRESSURE AIRMASS DROPS SOUTHEAST. THE ECMWF HAS
GENERALLY BEEN THE COLDER OF THE MODELS WITH THIS SYSTEM...THOUGH IT
HAS MODERATED SOMEWHAT IN RECENT RUNS. NEVERTHELESS...A COLD 36 HRS
IS IN STORE. THURSDAY MORNING WILL LIKELY DROP INTO THE LOWER TO
MIDDLE 20S...COINCIDENT WITH 15-20 KT WINDS. OUR LATEST APPARENT
TEMPERATURE GRIDS SHOW THE POTENTIAL FOR WIND CHILL ADVISORY
CRITERIA FOR A FEW HOURS LATE WEDNESDAY NIGHT. IT IS WORTH NOTING
THAT OUR CRITERIA FOR ISSUING WIND CHILL ADVISORIES INCREASED ON
DECEMBER 1ST 2014. THE NEW CRITERIA IS 15 DEGREES IN COASTAL
LOCATIONS OR 10 DEGREES INLAND. WE WILL ADD MENTION TO THE HAZARDOUS
WEATHER OUTLOOK.
STRONG COLD ADVECTION CONTINUING ON THURSDAY WILL YIELD BLUSTERY
CONDITIONS. BASED ON THE LATEST THICKNESS PROGS WE LOWERED HIGHS TO
THE UPPER 30S NORTH TO LOWER 40S SOUTH. THURSDAY NIGHT WILL AGAIN BE
COLD AS HIGH PRESSURE REMAINS TO THE WEST. THERE WERE EARLIER
INDICATIONS THAT THE BOUNDARY LAYER COULD DECOUPLE AND ALLOW FOR LOW
TEMPS IN THE TEENS. MORE RECENT MODEL RUNS SHOW A WEAK SHORTWAVE
MOVING THROUGH OVERNIGHT WITH STRENGTHENING 850 MB WINDS PREVENTING
SURFACE WINDS FROM GOING CALM. WE MAINTAINED LOW TEMPS IN THE LOW TO
MID 20S.
THE UPPER LEVEL PATTERN TRANSITIONS TO A BROAD TROUGH ACROSS THE
CENTRAL UNITED STATES FRIDAY INTO THE WEEKEND WITH THE SURFACE HIGH
EVENTUALLY MOVING INTO THE NORTHEAST STATES. MOISTURE WILL BEGIN TO
INCREASE LATE IN THE WEEKEND WITH INCREASING CLOUDS AND POSSIBLE
RAIN SHOWERS SATURDAY NIGHT AND SUNDAY. TEMPS WILL REMAIN BELOW
NORMAL BUT HIGHS WILL GENERALLY BE IN THE 50S.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
EXTENSIVE IFR CIGS THROUGH THE COASTAL CORRIDOR AT 12Z WITH LOW LEVEL
WINDS RUNNING TOO STRONG TO BE A CONCERN FOR FOG/REDUCED VSBYS.
LATEST FORECAST SOUNDINGS SUGGEST IFR CIGS WILL HANG IN THROUGH
MUCH OF THIS MORNING AND THEN LIFT TO MVFR BY EARLY AFTERNOON BEFORE
A BIT OF A BREAK OUT PRIOR TO BANDS OF CONVECTIVE RAINS REACH THE
TERMINALS AFTER MID AFTERNOON. SURFACE WINDS WILL BE GUSTY AHEAD
OF THE RAINS WITH GUSTS TOPPING 25 KT AT KCHS AND 20 KT AT KSAV.
THE COLD FRONT WILL MOVE OFF THE COAST THIS EVENING WITH CONDITIONS
FAVORING VFR TONIGHT IN THE WAKE OF THE FRONT.
EXTENDED AVIATION OUTLOOK...VFR.
&&
.MARINE...
LATE THIS MORNING...BASED ON RECENT WEB CAMS AND CHARLESTON HARBOR
PILOT BOAT REPORTS HAVE OPTED TO EXTEND THE DENSE FOG ADVISORY
THROUGH 6PM.
THE COOL STABLE NEAR SHORE WATERS TYPIFIED BY THE 5-7 KT OF WIND
OVERNIGHT AT GRAYS REEF WHILE TEMPS REACHING THE MID 60S ALONG
THE GEORGIA COAST SUPPORTIVE OF 15 KT WINDS WITH THE STRONGEST FLOW
RELEGATED TO WARMER WATERS OFFSHORE. THE SMALL CRAFT ADVISORIES IN
OUR NEAR SHORE WATERS WILL BE MARGINAL TODAY ONCE YOU GET AWAY
FROM THE LAND/SEA INTERFACE BUT WE MAINTAINED 4-6 FT SEAS TO
KEEP PERSISTENCE. THE HIGHEST SEAS IN NEAR SHORE LEGS SHOULD OCCUR
ACROSS THE NORTHEAST PART OF AMZ350. THE CHARLESTON HARBOR WILL
BE GUSTY AT TIMES TODAY...ESPECIALLY THE UPPER REACHES WHERE THE
WARMER SURFACE TEMPS OCCUR. THE FRONT WILL MOVE OFFSHORE LATER
TONIGHT WITH SOME JETTING OF THE W AND NW FLOW OFF THE GEORGIA
COAST. WE BUMPED UP WINDS A BIT FROM GRAYS REEF SEAWARD TO TREND.
WINDS/SEAS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA MONDAY
THROUGH WEDNESDAY. CONDITIONS QUICKLY DETERIORATE WEDNESDAY EVENING
BEHIND A STRONG COLD FRONT. STRONG LOW-LEVEL WINDS AND COLD AIR
ADVECTION WILL YIELD WINDS TURNING AROUND TO THE NORTH AND
INCREASING TO 25-30 KT. FREQUENT 35 KT GUSTS ARE INCREASINGLY
LIKELY WEDNESDAY NIGHT INTO THURSDAY MORNING ACROSS THE WARMER
WATERS BEYOND ABOUT 15 NM FROM SHORE. A PERIOD OF GALE
WATCHES/WARNINGS IS LIKELY FOR PORTIONS OF THE WATERS DURING THIS
TIME.
CONDITIONS QUICKLY IMPROVE LATER THURSDAY INTO THE WEEKEND AS THE
HIGH PRESSURE SYSTEM WEAKENS AND EVENTUALLY SHIFTS NORTHEAST.
&&
.CLIMATE...
RECORD HIGH TEMPERATURES JAN 4...
CHS 77/2005 AND PREVIOUS...
CXM 75/1955...
SAV 80/2004...
RECORD HIGH MINIMUM TEMPERATURES JAN 4...
CHS 58/1950 AND PREVIOUS...
CXM 61/2007...
SAV 60/2004 AND PREVIOUS...
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...LAKE WIND ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR SCZ045.
MARINE...DENSE FOG ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ330-350-
352-354.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR AMZ352.
SMALL CRAFT ADVISORY UNTIL 5 AM EST MONDAY FOR AMZ350.
SMALL CRAFT ADVISORY UNTIL 11 AM EST MONDAY FOR AMZ374.
SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR AMZ330.
&&
$$
NEAR TERM...BSH
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...JRL
CLIMATE...
AREA FORECAST DISCUSSION
NWS JACKSON KY
104 PM EST SUN JAN 4 2015
.UPDATE...
ISSUED AT 1253 PM EST SUN JAN 4 2015
UPDATED THE FORECAST TO BEST REFLECT THE ONGOING RADAR TRENDS...WITH
THE COLD FRONT AND LINE OF SHOWERS HAVING SLOWED AS IT MOVED ACROSS
THE HIGHER TERRAIN IN THE SE PORTION OF THE STATE...AND IS NOW
FINALLY MOVING EAST OF THE CWA. SCATTERED LIGHT SHOWERS ARE STARTING
TO MOVE ACROSS WESTERN AND CENTRAL KY DUE TO WRAP AROUND MOISTURE
FROM THIS SYSTEM. STILL HAVE THIS PRECIP MAKING IT IN HERE DURING THE
LATE AFTERNOON HOURS...WITH TEMPERATURES COOLING CONSIDERABLY THROUGH
THE REST OF THE DAY.
UPDATE ISSUED AT 936 AM EST SUN JAN 4 2015
UPDATED POPS TO REFLECT THE CURRENT PLACEMENT OF A LINE OF SHOWERS
JUST ALONG AND AHEAD OF THE COLD FRONT WHICH IS TRAVERSING EASTERN
KY. EXPECT THE FRONT...AS WELL AS THE LINE OF SHOWERS...TO BE EAST OF
THE REGION IN THE NEXT COUPLE OF HOURS. ENDED UP SPEEDING UP THE
ONGOING FORECAST BY AN HOUR TO BETTER DEPICT THIS MOVEMENT. ALSO
LOADED IN THE LATEST OBSERVATIONAL DATA FOR TEMPS...DEW POINTS...AND
WINDS...INTO THE NEAR TERM FORECAST TO MAKE SURE EACH OF THESE
PARAMETERS WAS WELL REFLECTED OVER THE NEXT FEW HOURS.
UPDATE ISSUED AT 730 AM EST SUN JAN 4 2015
THE COLD FRONT IS NOW ENTERING EAST KENTUCKY BRINGING A NARROW BAND
OF MODERATE RAINS AND GUSTY WINDS OF BETWEEN 30 AND 40 MPH. HAVE
TIMED THIS THROUGH THE CWA IN THE GRIDS. TEMPERATURES WILL BE A
CHALLENGE OVER THE NEXT COUPLE OF HOURS WITH MOST PLACES
EXPERIENCING THEIR HIGH TEMPERATURE FOR THE DAY ATTM WITH FALLING
TEMPERATURES TO FOLLOW THROUGH THE MORNING AND INTO THE AFTERNOON.
DID UPDATE THE TEMPS AND DEWPOINTS FOR THE NEXT FEW HOURS BASED ON
THE FRONT AND THE CURRENT READINGS. THESE FRESHENED GRIDS HAVE BEEN
SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 320 AM EST SUN JAN 4 2015
07Z SFC ANALYSIS SHOWS A DEEPENING AREA OF LOW PRESSURE MOVING INTO
THE OHIO VALLEY. THIS LOW IS DRAGGING A COLD FRONT THROUGH KENTUCKY
TRAILING A BAND OF STEADY LIGHT TO MODERATE RAIN SHOWERS PASSING
THROUGH EASTERN KENTUCKY. THE HEAVIER SHOWERS HAVE SETTLED DOWN AND
MOVED OFF TO THE EAST WHILE MORE SCATTERED SHOWERS ARE FOUND OVER
CENTRAL KENTUCKY ALONG AND JUST AHEAD OF THE COLD FRONT. EAST
KENTUCKY IS ENJOYING A VERY MILD EARLY JANUARY NIGHT AHEAD OF THE
COLD FRONT WITH TEMPERATURES IN THE MID AND UPPER 50S WHILE DEWPOINTS
ARE NOT MUCH LOWER. WINDS HAVE BEEN RATHER LIGHT FROM THE SOUTH
THROUGH THE AREA DESPITE THE TIGHTENING PRESSURE GRADIENT AND WINDS
ROARING JUST OFF THE SFC...AS SEEN IN THE JKL VWP.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM AS WE
ENTER A PERIOD OF SHARP WX TRANSITION. A FAIRLY DEEP FULL LATITUDE
TROUGH WILL SWEEP INTO THE OHIO VALLEY TODAY WITH ITS CORE BATCH OF
ENERGY PASSING THROUGH EAST KENTUCKY BY 00Z. VERY FAST FLOW THROUGH
THE BASE OF THE LARGE...BUT NOT SETTLING TOO FAR SOUTH...TROUGH THEN
WILL KEEP MINOR WAVES MOVING PAST ALOFT TONIGHT AND THROUGH THE DAY
MONDAY. GIVEN THE CLOSE MODEL AGREEMENT HERE WILL CONTINUE TO FAVOR A
BLEND OF THE HRRR AND NAM12 TODAY FOLLOWED BY THE ECMWF AND NAM12 FOR
TONIGHT AND MONDAY.
SENSIBLE WEATHER WILL FEATURE THE WARMEST TEMPERATURES OF THE
FORECAST EARLY THIS MORNING AHEAD OF THE COLD FRONT. THIS BOUNDARY
WILL GO THROUGH BY MID MORNING...THOUGH...AND START US ON OUR DESCENT
TO SINGLE DIGIT TEMPS THAT WILL BE IN HERE BY THURSDAY MORNING. THE
RAIN ASSOCIATED WITH THE COLD FRONT THIS MORNING WILL COME TO AN END
WITH ITS PASSAGE...THOUGH THAT SHORTWAVE CROSSING OVERHEAD THIS
AFTERNOON AND A COMBINATION OF WRAP AROUND AND UPSLOPE FLOW WILL
LIKELY LEAD TO A REDEVELOPMENT OF LIGHT PCPN MOVING IN FROM THE
NORTHWEST BY LATE AFTERNOON. AS TEMPERATURES COOL INTO THE EVENING
EXPECT THE LINGERING LIGHT SHOWERS TO TRANSITION TO SNOW SHOWERS FOR
A BRIEF TIME. THESE WILL BE A BIT MORE ROBUST IN THE HIGHER TERRAIN
NEAR THE VIRGINIA BORDER POTENTIALLY RESULTING IN A DUSTING OF
ACCUMULATION BY EARLY MONDAY MORNING. DRIER AIR AND ARRIVING HIGH
PRESSURE WILL PUT AN END TO ANY LEFTOVER FLURRIES MONDAY MORNING...
THOUGH TEMPERATURES WILL STRUGGLE TO CLIMB OUT OF THE 20S.
ONCE AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPS...TD...
AND WINDS UP TO 21Z TODAY AND THEN THE SUPERBLEND THROUGH 00Z
TUESDAY. DID MAKE SOME SLIGHT ADJUSTMENTS TO POINT TEMPERATURE DATA
FOR MAXES AND MINS THROUGH THE PERIOD. AS FOR POPS...ENDED UP SIMILAR
TO A BLEND OF THE GUIDANCE TODAY BUT WENT ABOVE ALL OF IT FOR THE
LIGHT RAIN AND SNOW CHANCES LATER THIS EVENING AND THE FIRST PART OF
TONIGHT...MONDAY WAS KEPT DRY IN LINE WITH ALL THE MOS.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 342 AM EST SUN JAN 4 2015
THE EXTENDED PORTION OF THE FORECAST WILL BEGIN ON MONDAY NIGHT WITH
A PROGRESSIVE UPPER LEVEL PATTERN THAT KEEPS A BROAD TROUGH OVER THE
NORTHEASTERN CONUS THROUGH MUCH OF THE EXTENDED. THROUGH
SATURDAY...A SERIES OF SHORTWAVES DIVE SOUTHEAST INTO THE OH VALLEY
REGION. THE FIRST WAVE MOVES THROUGH ON TUESDAY AND THOUGH MOISTURE
STARVED AND MOST OF THE LIFT AND MOISTURE BEING NORTH...WILL KEEP
SOME FLURRIES AND SNOW SHOWERS JUST SKIRTING THE NORTHERN PORTION OF
THE CWA. MODEL SOUNDINGS KEEP THE LOWER LEVELS QUITE DRY SO COULD
ALSO GO COMPLETELY DRY OVER THE AREA WITH THIS FEATURE. THE FIRST
SHOT OF COLDER AIR FILTERS IN BEHIND THIS FRONT FOR WEDNESDAY. THEN
ANOTHER SHORTWAVE MOVES THROUGH LATER IN THE DAY ON WEDNESDAY BUT
THE FRONT BEING DRY WITH THIS ONE WITH JUST CLOUD COVER EXPECTED.
THE COLD AIR BEHIND THIS FEATURE WILL BRING SOME FRIGID AIR INTO
EASTERN KENTUCKY. DOMINANT SURFACE HIGH PRESSURE WILL RESIDE FROM
THE UPPER PLAINS AND MOVES SOUTHEAST INTO THE MS VALLEY AND TN
VALLEY...KEEPING EASTERN KENTUCKY DRY THROUGH MUCH OF THE EXTENDED.
THE COLD AIR AND WIND EXPECTED FOR THURSDAY WILL PRODUCE SOME WIND
CHILLS INTO THE NEGATIVE TEENS. BECAUSE OF THIS...WILL MENTION THIS
IN THE HWO AS WELL AS ISSUE AN SPS FOR THIS. MODELS DIVERGE
SIGNIFICANTLY AT THE END OF THE EXTENDED AS THE GFS KEEPS THE AREA
DRY BUT THE EURO HAS THE THE UPPER TROUGH LIFTING NORTH ALLOWING A
NEW FEATURE TO DEVELOP AND MOVE NORTHEAST OUT OF THE GULF OF
MEXICO. DID GET SOME POPS FROM THE ALL MODEL BLEND SO WENT WITH
SLIGHTLY LOWER POPS KEEP SLIGHT CHANCE OVER THE AREA. THIS IS DUE
TO COLLABORATION WITH NEIGHBORING OFFICES AS WELL AS THE TRENDS OF
THE EURO. THE AIR MASS IN PLACE DURING THAT TIME IS ALSO QUITE DRY TO
OVERCOME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 104 PM EST SUN JAN 4 2015
A COLD FRONT THAT TRAVERSED MUCH OF EASTERN KY EARLIER THIS MORNING
IS CURRENTLY EXITING THE STATE TO THE EAST. IN IT/S WAKE...RAIN
SHOWERS HAVE CEASED ACROSS MOST OF THE TAF SITES /KSJS MAY HAVE A FEW
LINGERING SHOWERS FOR THE NEXT HOUR AS IT IS FARTHER EAST/. WRAP
AROUND MOISTURE FROM THIS SYSTEM WILL BEGIN IMPACTING THE REGION
AGAIN LATER THIS AFTERNOON AND INTO THE OVERNIGHT. SHOWERS SHOULD BE
LIGHT...BUT THE INTRUSION OF COLD AIR MAY LEAD TO SOME NON-ACCUMULATING
SNOW MIXING IN. THE WIND WILL CONTINUE TO BE A FACTOR FOR MUCH OF
THE FORECAST PERIOD. STRONG SW TO NE FLOW ALOFT...AND TIGHT PRESSURE
GRADIENTS...WILL RESULT IN WIND GUSTS BETWEEN 15 AND 25KTS FOR THE
REMAINDER OF TODAY AND THROUGHOUT THE NIGHT. GRADIENTS WILL LESSON AS
HIGH PRESSURE FINALLY MOVES IN TOMORROW MORNING. BASED ON FORECAST
SOUNDINGS...AND UPSTREAM OBS...EXPECT MVFR CONDITIONS TO PERSIST THIS
AFTERNOON AND THROUGH THE NIGHT. THERE IS THE POSSIBILITY THAT SOME
LOCATIONS COULD DROP DOWN TO LIFR AT TIMES AS WELL THROUGHOUT THE
NIGHT. CLOUDS WILL FINALLY START BREAKING OUT TOMORROW MORNING FROM
WEST TO EAST WITH VFR CONDITIONS EXPECTED FOR THE END OF THE TAF
PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1235 PM EST Sun Jan 4 2015
...Forecast Update...
Issued at 1235 PM EST Sun Jan 4 2015
An arctic boundary is currently situated from the just west of the
Wabash River Valley southwestward to the Red River Valley. This
feature will quickly slide through our area this afternoon into the
early evening. Meanwhile, an upper level disturbance will slide
through, with the best forcing across south central KY. The
combination of lingering 1000-850 mb moisture, steepening low level
lapse rates, and the disturbance will be able to produce isolated to
scattered coverage of mostly rain showers. Perhaps a few showers
across southern Indiana could briefly change to snow.
Forecast remains on track and have only updated to reflect current
trends, and reduce chances of measurable precipitation by 5 to 10
percent. Temperatures will fall through the 30s this afternoon and
evening, on their way to the upper teens and low 20s tonight.
.SHORT TERM (Now through Monday)...
Issued at 230 AM EST Sun Jan 4 2015
Big weather changes are in store during the short term period as a
strong storm system continues to cross the Ohio Valley. As of 3
am, the latest water vapor imagery and 500 mb RAP heights shows
intense southwesterly flow remaining across the forecast area as the
main shortwave trough lifts through Missouri into northern Illinois.
A secondary PV anomaly is crossing through Oklahoma. At the surface,
a cold front is beginning to move into the LMK CWA. Ahead of this
boundary, conditions are very mild as readings have held up in the
upper 50s to near 60 degrees.
Plan on scattered/numerous rain showers and/or drizzle to persist
through the early morning hours, ending southwest to northeast as
the main upper level forcing lifts into Ohio. Then, for the
remainder of this morning, we`ll be under the influence of a dry
slot, waiting for the aforementioned secondary PV anomaly to pivot
across the Ohio Valley this afternoon. 04.00z guidance still shows a
good amount of PV advection with this wave, low level lapse rates
approaching 8-9C/km and weak instability. Meso-models depict
intermittent convective rain showers developing this afternoon and
some of the perkier ones may be strong enough to mix down gusty
winds 30-35 mph. As temperatures aloft crash and reach -10C, there
will be a brief window where precipitation may changeover to snow
showers, especially north of KY parkways. A quick dusting is
possible on grassy surfaces but overall not expecting any impacts.
High temperatures will occur this morning, then plan on readings to
steadily fall throughout the day, reaching the mid 30s to lower 40s
by mid/late afternoon. Combined with a brisk west wind 10-20 mph and
wind chills will be in the 20s by this evening. Quite a change in 24
hours.
As the new work and school week begins Monday morning, a fresh surge
of Arctic air will have taken hold of the forecast area. Plan on
morning temperatures in the teens to lower 20s. A steady
north/northwest wind will make it feel more like +5 to +10F. High
temperatures will be 15 to 20 degrees below normal, struggling to
reach the upper 20s.
.LONG TERM (Monday Night through Saturday)...
Issued at 248 AM EST Sun Jan 4 2015
...Very Cold Temperatures and Wind Chills Mid-Week...
A small, weakening area of low pressure will zip quickly by to our
north early Tuesday morning. Models have been fairly consistent and
continue to be in decent agreement with this feature, taking the
great majority of its associated precipitation to our north through
Illinois, central/northern Indiana, and Ohio. The best chance for
any dusting in the LMK CWA would be north of a Paoli-Madison line,
with scattered flurries possible as far south as the Interstate 64
corridor. Atmospheric cross-sections continue to show a good amount
of dry air in the low levels, even in the far north of the LMK CWA,
lending credence to the idea that there will be minimal impact here.
A very impressive dome of frigid high pressure will invade from the
northwest behind Tuesday`s system. This high, already very cold to
begin with, will slide across extensive snowpack in the Plains and
Midwest on its way to the Ohio and Tennessee Valleys, limiting
moderation of the airmass. On Wednesday, sunrise temperatures
should be in the teens, and will fall from there into the single
digits in Indiana and the lower and middle teens in Kentucky by
suppertime. Winds will be brisk and gusty in a tight pressure
gradient on the nose of the incoming high, possibly gusting to
around 20 mph as temperatures fall. Wind chills Wednesday afternoon
and evening over southern Indiana and northern Kentucky will be in
the -5 to -15 range.
By dawn on Thursday the center of the high will be right over us.
Any breeze will be light, and what breeze there is may be coming in
from the northwest off the Midwestern snow field. Skies should be
clear. So, very cold temperatures can be expected. Southern
Indiana locations will dip slightly below zero, with lows around
zero in Kentucky all the way down to the Tennessee border.
A weakening cold front will pass through on Friday morning
completely dry with high pressure centers ahead of and behind it,
blocking any moisture supply. Then, behind the departing front,
another Canadian high for Friday night/Saturday.
&&
.AVIATION (18Z TAF Update)...
Issued at 1214 PM EST Sun Jan 4 2015
An Arctic front currently stretches from the Wabash River Valley
southwestward to the Red River Valley. This feature will slide
through the TAF sites later this afternoon, with a subtle veering of
the surface winds to a more NW component. Winds will continue to
gust mainly between 25 and 30 mph at times behind this boundary,
gradually slackening after midnight as the surface high begins to
build in.
Ceilings have been mostly MVFR and will continue to mention this
trend prevailing through the evening before conditions improve
around Midnight. Given the mixy low level boundary layer, ceilings
could waffle below fuel-alternate and above the MVFR/VFR threshold
for brief periods of time. Skies should be mostly clear as we near
dawn on Monday.
Only other concern is the scattered shower activity expected this
afternoon into the early evening due to steepening low level lapse
rates and passing mid level disturbance. This will be most prolific
at BWG, however will mention VCSH at all sites through early this
evening.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........BJS
Short Term.....ZBT
Long Term......13
Aviation.......BJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1214 PM EST Sun Jan 4 2015
...Updated Aviation Discussion...
.SHORT TERM (Now through Monday)...
Issued at 230 AM EST Sun Jan 4 2015
Big weather changes are in store during the short term period as a
strong storm system continues to cross the Ohio Valley. As of 3
am, the latest water vapor imagery and 500 mb RAP heights shows
intense southwesterly flow remaining across the forecast area as the
main shortwave trough lifts through Missouri into northern Illinois.
A secondary PV anomaly is crossing through Oklahoma. At the surface,
a cold front is beginning to move into the LMK CWA. Ahead of this
boundary, conditions are very mild as readings have held up in the
upper 50s to near 60 degrees.
Plan on scattered/numerous rain showers and/or drizzle to persist
through the early morning hours, ending southwest to northeast as
the main upper level forcing lifts into Ohio. Then, for the
remainder of this morning, we`ll be under the influence of a dry
slot, waiting for the aforementioned secondary PV anomaly to pivot
across the Ohio Valley this afternoon. 04.00z guidance still shows a
good amount of PV advection with this wave, low level lapse rates
approaching 8-9C/km and weak instability. Meso-models depict
intermittent convective rain showers developing this afternoon and
some of the perkier ones may be strong enough to mix down gusty
winds 30-35 mph. As temperatures aloft crash and reach -10C, there
will be a brief window where precipitation may changeover to snow
showers, especially north of KY parkways. A quick dusting is
possible on grassy surfaces but overall not expecting any impacts.
High temperatures will occur this morning, then plan on readings to
steadily fall throughout the day, reaching the mid 30s to lower 40s
by mid/late afternoon. Combined with a brisk west wind 10-20 mph and
wind chills will be in the 20s by this evening. Quite a change in 24
hours.
As the new work and school week begins Monday morning, a fresh surge
of Arctic air will have taken hold of the forecast area. Plan on
morning temperatures in the teens to lower 20s. A steady
north/northwest wind will make it feel more like +5 to +10F. High
temperatures will be 15 to 20 degrees below normal, struggling to
reach the upper 20s.
.LONG TERM (Monday Night through Saturday)...
Issued at 248 AM EST Sun Jan 4 2015
...Very Cold Temperatures and Wind Chills Mid-Week...
A small, weakening area of low pressure will zip quickly by to our
north early Tuesday morning. Models have been fairly consistent and
continue to be in decent agreement with this feature, taking the
great majority of its associated precipitation to our north through
Illinois, central/northern Indiana, and Ohio. The best chance for
any dusting in the LMK CWA would be north of a Paoli-Madison line,
with scattered flurries possible as far south as the Interstate 64
corridor. Atmospheric cross-sections continue to show a good amount
of dry air in the low levels, even in the far north of the LMK CWA,
lending credence to the idea that there will be minimal impact here.
A very impressive dome of frigid high pressure will invade from the
northwest behind Tuesday`s system. This high, already very cold to
begin with, will slide across extensive snowpack in the Plains and
Midwest on its way to the Ohio and Tennessee Valleys, limiting
moderation of the airmass. On Wednesday, sunrise temperatures
should be in the teens, and will fall from there into the single
digits in Indiana and the lower and middle teens in Kentucky by
suppertime. Winds will be brisk and gusty in a tight pressure
gradient on the nose of the incoming high, possibly gusting to
around 20 mph as temperatures fall. Wind chills Wednesday afternoon
and evening over southern Indiana and northern Kentucky will be in
the -5 to -15 range.
By dawn on Thursday the center of the high will be right over us.
Any breeze will be light, and what breeze there is may be coming in
from the northwest off the Midwestern snow field. Skies should be
clear. So, very cold temperatures can be expected. Southern
Indiana locations will dip slightly below zero, with lows around
zero in Kentucky all the way down to the Tennessee border.
A weakening cold front will pass through on Friday morning
completely dry with high pressure centers ahead of and behind it,
blocking any moisture supply. Then, behind the departing front,
another Canadian high for Friday night/Saturday.
&&
.AVIATION (18Z TAF Update)...
Issued at 1214 PM EST Sun Jan 4 2015
An Arctic front currently stretches from the Wabash River Valley
southwestward to the Red River Valley. This feature will slide
through the TAF sites later this afternoon, with a subtle veering of
the surface winds to a more NW component. Winds will continue to
gust mainly between 25 and 30 mph at times behind this boundary,
gradually slackening after midnight as the surface high begins to
build in.
Ceilings have been mostly MVFR and will continue to mention this
trend prevailing through the evening before conditions improve
around Midnight. Given the mixy low level boundary layer, ceilings
could waffle below fuel-alternate and above the MVFR/VFR threshold
for brief periods of time. Skies should be mostly clear as we near
dawn on Monday.
Only other concern is the scattered shower activity expected this
afternoon into the early evening due to steepening low level lapse
rates and passing mid level disturbance. This will be most prolific
at BWG, however will mention VCSH at all sites through early this
evening.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Short Term........ZBT
Long Term.........13
Aviation..........BJS
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1255 PM EST SUN JAN 4 2015
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO LIFT NORTH OF THE AREA THIS MORNING. A
COLD FRONT WILL APPROACH FROM THE WEST TODAY AND MOVE THROUGH THE
AREA TONIGHT. HIGH PRESSURE WILL BE OVER THE AREA MONDAY AND
TUESDAY. A DRY COLD FRONT WILL MOVE THROUGH AREA TUESDAY NIGHT
FOLLOWED BY ARCTIC HIGH PRESSURE BUILDING OVER THE AREA THE
REMAINDER OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1030 AM SUN...LATE MORNING UPDATE ADJUSTED MAINLY TO CAPTURE
PRECIP TRENDS. A PRE-FRONTAL BAND OF MODERATE TO HEAVY SHOWERS
CONTINUES TO PUSH ACROSS THE AREA AND MOST OF THE SHOWER ACTIVITY
HAS PUSHED EAST OF HWY 17. A FEW LIGHTNING STRIKES ALSO SEEN
ACROSS MAINLAND DARE AND MAINLAND HYDE COUNTIES AND WILL KEEP
SLIGHT CHANCE OF THUNDER. HRRR CONTINUES TO HAVE A GOOD HANDLE
ON CURRENT ACTIVITY SHOWING SHOWERS WEAKENING AS THEY CONTINUE TO
PUSH EASTWARD WITH A RELATIVE MINIMUM IN ACTIVITY EARLY THIS
AFTERNOON BEFORE ANOTHER LINE OF SHOWERS ASSOCIATED WITH THE
FRONT...CURRENTLY MOVING ACROSS THE WESTERN PIEDMONT...MOVES INTO
EASTERN NC MID TO LATE AFTERNOON. MARGINAL THREAT OF SVR DUE TO
STRONG WIND FIELDS AND SHEAR...BUT LAPSE RATES WEAK AND CLOUD
COVER AND SCT SHRA COVERAGE WILL INHIBIT INSTABILITY AS WELL. DID
INCLUDE GUSTY WINDS AND HEAVY RAIN MENTIONED LATE AFTN/EARLY EVENING
WITH MAIN FRONTAL BAND PCPN. TEMPS IN UPPER 60S TO LOW 70S LATE
THIS MORNING AND WILL NOT TAKE MUCH INSOLATION TO REACH MID TO UPR
70S FOR MAX TEMPS...WHICH WILL BE NEAR RECORD HIGHS SOME AREAS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
AS OF 400 AM SUNDAY...PER NEAR TERM DISCUSSION...MARGINAL THREAT OF
ISOLATED SVR WIND GUST WITH FRONTAL PCPN BAND MOVING ACROSS DURING
EVENING HOURS. FRONT EXPECTED TO BE OFF COAST SHORTLY AFTER MIDNIGHT
WITH CLEARING SKIES AND COOLER TEMPS MOVING IN OVERNIGHT. LOWS FROM
MID 40S INLAND TO AROUND 50 COAST.
&&
.LONG TERM /MONDAY THROUGH SUNDAY/...
AS OF 404 AM SAT...LONG TERM PERIOD WILL START OUT WITH SEASONABLE
TEMPERATURES AND DRY CONDITIONS FOLLOWED BY ARCTIC AIR MASS AND
COLDEST AIR OF THE SEASON BY WEDNESDAY NIGHT THROUGH FRIDAY
MORNING.
FOR MONDAY...SPRAWLING HIGH PRES BUILDS IN FROM THE GREAT LAKES
REGION/OHIO VALLEY WITH TEMPS DROPPING BACK TO NEAR
CLIMO...LOW/MID 50S UNDER SUNNY SKIES. THE HIGH WILL BE CENTERED
OVER THE MID ATLANTIC STATES MONDAY NIGHT WITH EXCELLENT
RADIATIONAL COOLING EXPECTED WITH CALM WINDS AND CLEAR SKIES. LOWS
DROP BACK TO THE 20S AWAY FROM THE COAST TO NEAR FREEZING BEACHES.
ON TUESDAY...FLOW QUICKLY BACKS SOUTH THEN SOUTH IN RESPONSE TO
NEXT DIGGING STRONG SHORTWAVE TO THE WEST. LARGE DIURNAL
TEMPERATURE SWING EXPECTED AS LOW LEVEL THICKNESSES...MOS GUIDE
BOTH SUGGESTING HIGHS INTO THE UPPER 50S TO LOWER 60S...HIGHEST
SOUTH. TUESDAY NIGHT WILL BE RELATIVELY MILD AS WESTERLY LOW LEVEL
FLOW CONTINUES TO KEEP BNDRY LAYER SLIGHTLY MIXED. LOWS WILL BE IN
THE 30S TO NEAR 40.
COLDEST AIR MASS OF THE SEASON LOOKS TO ARRIVE WED INTO THUR.
MED/LONG RANGE MODEL SUITE IN REMARKABLY GOOD AGREEMENT ON DEEP
ARCTIC TROUGH DIGGING INTO THE CENTRAL CONUS ON TUE NIGHT THEN
TRANSLATING TO THE EASTERN CONUS WEDNESDAY NIGHT INTO THUR. TRICKY
TEMP FORECAST ON WED...AS HIGHS MAY BE REALIZED IN THE MORNING
HOURS BEFORE STRONG CAA ENSUES IN THE AFTERNOON WITH TEMPS
DROPPING. COLD AIR ADVECTION WILL STRENGTHEN WED NIGHT WITH WINDS
STAYING ELEVATED IN THE 10 TO 15 MPH RANGE WITH HIGHER GUSTS.
THESE WINDS COMBINED WITH FCST LOWS IN THE MID/UPR TEENS WILL
PRODUCE WIND CHILL VALS WELL INTO THE SINGLE DIGIT RANGE ABOVE
ZERO. WILL CONTINUE TO HIGHLIGHT THE COLD WIND CHILLS IN THE HWO.
THREAT FOR SNOW SHOWERS ACROSS THE OUTER BANKS...NAMELY DARE
COUNTY...AS LOW LEVEL NON SHEARED FLOW WILL VEER TO NNW TO ALMOST
TRUE NORTH BY LATE WED NIGHT. THE GUSTY WINDS FLOWING OVER WARM
SOUND AND OCEAN WATERS COULD PRODUCE SOME `SOUND OR OCEAN EFFECT`
SNOW SHOWERS WED NIGHT THROUGH THUR. ANY ACCUMS SHOULD BE TRIVIAL
AND HAVE INCLUDED CHANCE SNOW SHOWERS IN THE GRIDS FOR DARE
COUNTY.
THURSDAY WILL BE QUITE COLD WITH HIGHS STILL EXPECTED TO BE AROUND
FREEZING OR JUST BELOW. WINDS WILL BEGIN TO DIMINISH AS GRADIENT
BEGINS TO RELAX...THOUGH STILL EXPECT WIND CHILLS TO BE IN THE
TEENS TO LOWER 20S IN THE AFTERNOON. ANOTHER COLD NIGHT THURSDAY
NIGHT IN THE TEENS WITH ARCTIC HIGH TRANSLATING OVER THE
AREA...THOUGH VERY LITTLE WIND AND WIND CHILL VALS SHOULD NOT BE
MUCH OF AN ISSUE.
A SLOW MODERATION IN TEMPS FRI INTO NEXT WEEKEND AS HEIGHTS SHOULD
REMAIN A BIT BELOW NORMAL PER ENSEMBLE MEMBERS AND THEREFORE HIGHS
EXPECTED IN THE 40S TO LOWER 50S. NEXT PRECIP CHANCE COULD ARRIVE
LATE IN THE WEEKEND THOUGH STILL LOTS OF UNCERTAINTY WITH RETURN
FLOW.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH 18Z MONDAY/...
AS OF 1230 PM SUNDAY...PRE-FRONTAL MOISTURE CONTINUES TO MARCH
EASTWARD ALONG THE COAST THIS AFTERNOON WITH THE FRONT STILL WELL
TO THE WEST. GIVEN THIS...EXPECT VCSH THROUGH THE AFTERNOON WITH
MVFR CEILINGS. GUSTY SOUTH WINDS AHEAD OF THE FRONT CAN ALSO BE
EXPECTED. SOME BREAKS IN THE CLOUDS CAN NOT BE RULED OUT AS THE
INFLUX OF MOISTURE AHEAD OF THE FRONT IS STILL ACROSS CENTRAL
NC/SC. THIS WILL MOVE EASTWARD...BUT THE UPPER LEVEL SUPPORT...LIFT
AND AVAILABLE MOISTURE LOOKS TO WANE A BIT BY THE TIME IT ARRIVES.
SO...THIS AFTERNOON/EVENING ANTICIPATE RAIN SHOWERS WITH ISOLATED
THUNDER. THE FRONT WILL CROSS OVERNIGHT WITH DRIER AIR MOVING INTO
THE REGION. GUSTY WINDS WILL DIMINISH AND VEER TO THE
NW...ALTHOUGH STILL ELEVATED. VFR CEILINGS BY AROUND MID-NIGHT
ACROSS MUCH OF THE AREA AND WILL REMAIN AS HIGH PRESSURE MOVES
INTO THE AREA. WINDS WILL START TO GUST FROM THE NW BY THE
AFTERNOON HOURS ON MONDAY.
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 404 AM SUN...DRY AIRMASS WILL MOVE IN ON MONDAY WITH SKIES
QUICKLY BECOMING MOSTLY CLEAR. VFR MONDAY WITH LIGHT NORTHWEST
FLOW. SURFACE WINDS BECOME SOUTHWEST TUESDAY AROUND 10 KNOTS AHEAD
OF NEXT FRONT. A DRY COLD FRONT WILL PASS THROUGH WEDNESDAY WITH
WINDS NORTHWEST 10-15 KNOTS WITH HIGHER GUSTS. NW WINDS WILL
REMAIN ELEVATED ON WED NIGHT WITH DRY ARCTIC AIRMASS MOVING IN AND
LINGERING THROUGH THURSDAY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1030 AM SUNDAY...LITTLE CHANGE TO PREVIOUS FCST WINDS AND
SEAS AS MODELS REMAIN IN GOOD AGREEMENT WITH INCREASING S-SW WINDS
INTO THIS EVENING AHEAD OF APPROACHING COLD FRONT...THEN WINDS
SHIFTING TO NW OVERNIGHT WITH FRONTAL PASSAGE. SEAS EXPECTED TO
PEAK AT 7-10 FT THIS AFTERNOON AND EVENING...THEN GRADUALLY
SUBSIDE INTO MONDAY.
LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 404 AM SUN...WINDS AND SEAS WILL SLOWLY DIMINISH MONDAY AS
HIGH PRESSURE BUILDS IN FROM THE WEST. SCA SHOULD END ON MONDAY.
SW TO W FLOW INCREASES ON TUESDAY AS A STRONG WAVE MOVES BY TO THE
NORTH AND PRODUCES A PERIOD OF SCA WINDS AND SEAS LATE TUE. WINDS
MAY DIMINISH A BIT WED BUT QUICKLY STRENGTHEN WITH PASSAGE OF A
STRONG COLD FRONT. WINDS BEHIND THE FRONT WILL BE IN THE STRONG
SCA RANGE AND COULD SEE A PERIOD OF GALES WED NIGHT INTO EARLY
THUR AS MOST MODELS INDICATING WINDS GUSTING 35 TO 40 KT. WINDS
WILL DIMINISH BY THUR AFTERNOON AND THEN VEER NE FRI AS ANOTHER
AREA OF HIGH PRES PASSES BY TO THE NORTH.
&&
.HYDROLOGY...
MINOR FLOODING IN THE NEUSE RIVER AT KINSTON WILL CONTINUE. THE
NEUSE RIVER IS FORECAST TO REMAIN AT MINOR FLOOD LEVELS THROUGH MID
WEEK. SEE THE LATEST FLSMHX FOR DETAILS.
&&
.CLIMATE...
RECORD HIGH TEMPERATURES POSSIBLE ON SUNDAY JANUARY 4 2015. BELOW IS
A LIST OF ASOS/AWOS/COOP STATIONS AND THE YEAR OF THEIR RECORD HIGHS
FOR SUNDAY.
VALUE LOCATION YEAR
===== ======== ====
78 NEW BERN 2004
78 GREENVILLE 2000
75 KINSTON 7SE 2000
75 CAPE HATTERAS 1972
75 MOREHEAD CITY1950
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST MONDAY FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 4 AM EST MONDAY FOR AMZ130.
SMALL CRAFT ADVISORY UNTIL 4 PM EST MONDAY FOR AMZ150-152-154-
156-158.
&&
$$
SYNOPSIS...JBM
NEAR TERM...JBM
SHORT TERM...JBM
LONG TERM...TL
AVIATION...TL/LEP
MARINE...JBM/TL
HYDROLOGY...JBM
CLIMATE...SEK/TL
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1259 PM EST SUN JAN 4 2015
.SYNOPSIS...
COLD FRONT CROSSES THIS AFTERNOON. GUSTY WINDS AND SNOW SHOWERS
FLURRIES IN ITS WAKE TONIGHT INTO MONDAY MORNING. HIGH PRESSURE
MONDAY EVENING. FAST CLIPPER TUESDAY FOLLOWED BY ARCTIC BLAST
WEDNESDAY/THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1030 AM UPDATE. FOCUSING ON BAND OF SHOWERS ALONG COLD FRONT THAT
WILL CROSS THE REMAINDER OF THE AREA THIS AFTERNOON...WITH GUSTY
WINDS.
PREVIOUS DISCUSSION...
ENHANCED POPS A BIT WITH THE SHOWERS RIGHT ALONG THE FRONT OUT TO
THE W. FCST OTHERWISE LARGELY ON TRACK.
PREV DISCN...
LOW PRESSURE CENTER DRAGS A COLD FRONT THROUGH THE AREA TODAY AS IT
CONSOLIDATES OVER THE EASTERN GREAT LAKES. MAIN PLUME OF RAINFALL
GOOD FOR ABOUT AN INCH GIVE OR TAKE OVER A 6 HOUR PERIOD EXITS FIRST
THING THIS MORNING. SHOWERS ACCOMPANY AND IMMEDIATELY FOLLOW THE
FRONT ITSELF...STILL IN WRN OHIO EARLY THIS MORNING AND W OF THE
FCST AREA AT DAWN.
THE FRONT WILL PUSH THROUGH THE AREA LATER THIS MORNING THROUGH
EARLY THIS AFTERNOON W TO E. STRONG PRESSURE GRADIENT WITH PRESSURE
RISE OF 8 MB/6 HRS THIS AFTERNOON INTO TONIGHT SUGGEST GOOD MIXING
AND MOMENTUM TRANSPORT. USED RUC MOMENTUM ALGORITHM TO ARRIVE AT
GUSTS TO 30 KTS HILLTOPS DURING THE FRONTAL PASSAGE TODAY AND
CONTINUING SEVERAL HOURS AFTER...WITH UP TO 40 KTS OVER THE HIGHER
TERRAIN...THESE GUSTS MAY PERSIST THERE MUCH OF THE NT TONIGHT.
THESE VALUES FALL SHY OF ADV CRITERIA THOUGH.
AFTER A DRY SLOT LATER TODAY...UPSLOPE SHOW SHOWERS SHOULD INCREASE
OVER THE HIGHER WINDWARD TERRAIN TONIGHT AS H85 TEMPERATURES CRASH
TO -10C OR LOWER OVERNIGHT...SUPPORTIVE OF ICE CRYSTALS. AM A
LITTLE UNDER WWD WITH UP TO AN INCH OVER THE HIGHER WINDWARD
TERRAIN. MOISTURE DEPTH INCREASES AS MAIN UPPER LEVEL S/W TROUGH
AXIS CROSSES THIS EVENING...ALSO GIVING RISE TO CRYSTAL GROWTH AND
SCATTERED RAIN SHOWERS CHANGING TO SNOW SHOWERS EVEN OUT ACROSS THE
LOWLANDS EARLY TONIGHT. OTHERWISE STRATOCU PERSISTS BENEATH
LOWERING SUBSIDENCE INVERSION THROUGH THE BALANCE OF THE NEAR TERM
PERIOD.
BLENDED IN MAINLY NAM BASED HOURLY TEMPERATURES IN THE STRONG COLD
ADVECTION...HIGHS OCCUR EARLY TODAY.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
PERIOD WILL BEGIN WITH SMALL CHANCES OF SNOW IN THE MOUNTAINS.
HOWEVER...ANY PRECIPITATION SHOULD END QUICKLY AS HIGH PRESSURE
MOVES EAST ACROSS THE REGION. THIS HIGH SHOULD RESULT IN DRY
WEATHER REGION-WIDE BY LATE MONDAY MORNING....AND CONTINUE INTO
MONDAY NIGHT.
A FAST MOVING LOW PRESSURE SYSTEM WILL THEN BRING PRECIPITATION
CHANCES BACK TO THE REGION LATE MONDAY NIGHT. MODELS DIFFER ON THE
TRACK OF THE LOW AND ASSOCIATED PRECIPITATION...WITH THE NAM
LIMITING ANY MEASURABLE TO OUR EXTREME NORTHERN AREAS. THE
GFS/ECMWF AND HPC 6-HR PRECIPITATION FORECAST SUGGESTS THE EDGE OF
THE MEASURABLE PRECIPITATION WILL BE FARTHER SOUTH. HAVE TWEAKED
THE POPS AND QPF GRIDS TOWARDS THE SOLUTION OF THE GFS/ECMWF/HPC.
AS A RESULT...HAVE LIKELY OR HIGHER POPS ACROSS OUR NORTHERN TWO
TIER OF COUNTIES FROM LATE MONDAY NIGHT INTO TUESDAY AFTERNOON.
BEHIND THE LOW...COLDER AIR AND WESTERLY WINDS WILL COMBINE WITH
SUFFICIENT MOISTURE TO BRING A GOOD CHANCE OF UPSLOPE SNOW TUESDAY
EVENING INTO THE OVERNIGHT HOURS.
THE UPSLOPE SNOW SHOULD DECREASE BY LATE TUESDAY NIGHT. HOWEVER...
ANOTHER UPPER LEVEL SYSTEM WILL SWEEP SOUTHEAST ACROSS THE AREA ON
WEDNESDAY...WITH SNOW SHOWERS CHANCES CONTINUING.
MET/MAV GUIDANCE IS QUITE CLOSE FOR MONDAY THROUGH TUESDAY...AND WAS
CLOSE TO WHAT WE HAVE IN OUR GRIDS...SO DID NOT MAKE ANY MAJOR
CHANGES. MEX GUIDANCE IS ALSO CLOSE TO OUR GRIDS FOR TUESDAY NIGHT
AND WEDNESDAY...SO ONLY SOME MINOR TWEAKS WERE MADE.
CURRENT THINKING IS THAT SNOWFALL AMOUNTS UP TO 2 INCHES ARE
POSSIBLE ACROSS OUR NORTHERN COUNTIES FROM LATE MONDAY NIGHT THROUGH
TUESDAY...WITH A FEW INCHES POSSIBLE IN THE NORTHERN MOUNTAINS LATE
TUESDAY THROUGH TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
FRONT END OF THE EXTENDED DEALS WITH THE TAIL END OF THE CLIPPER
TYPE LOW PRESSURE SYSTEM WITH DECREASING CHANCES OF SNOW OVER THE
NORTHERN TIER OF THE CWA THROUGH TUESDAY NIGHT. IN THE WAKE OF THE
SYSTEM...UPPER LEVEL LOW DEEPENS OVER THE GREAT LAKES WHILE SURFACE
HIGH PRESSURE BUILDS OVER THE MIDWEST AS IT MOVES IN FROM THE LEE OF
THE CANADIAN ROCKIES. OF INTEREST IS THE ECMWF THAT HAS THE HIGH
REACHING 1060MB OVER THE BLACK HILLS AREA IN SOUTH DAKOTA.
THAT HIGH PRESSURE SHOULD BE GOOD TO GO THROUGH THE END OF THE
WEEK...ALTHOUGH MAY NEED TO WATCH FOR ANOTHER GREAT LAKES CLIPPER
TYPE SYSTEM FRIDAY. LOW CONFIDENCE WITH THIS AT THIS POINT.
NOT TOO MANY CHANGES TO THE TEMPERATURES WEDNESDAY THROUGH THURSDAY
WITH HIGHS STRUGGLING TO HIT 20F AND LOWS BELOW 0F POSSIBLE
WEDNESDAY NIGHT. SKIES SHOULD CLEAR...BUT WIND STAYS UP...SO
RADIATIONAL COOLING NOT EXPECTED AT THIS TIME. THIS WILL KEEP VALLEY
TEMPERATURES FROM DROPPING FURTHER.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
18Z SUNDAY THRU 18Z MONDAY...
COLD FRONT EXITS THE MOUNTAINS BY 22Z. BIG FEATURE THIS PERIOD IS
THE STRONG AND GUSTY WINDS. AHEAD OF THE FRONT VFR CEILINGS AND
GUSTY SOUTH WINDS 20 TO 35 MPH. FRONT BRINGS GUSTY RAIN SHOWERS WITH
MVFR CONDITIONS...WITH GUSTS 30 TO 40 MPH. BEHIND THE FRONT...GUSTY
WEST WINDS 20 TO 30 MPH...HIGHER ON RIDGETOPS. A BRIEF PERIOD OF VFR
CEILINGS POSSIBLE BEFORE STRONG COLD ADVECTION BRINGS WIDESPREAD
MVFR CEILINGS BACK INTO THE AREA BY 00Z. FOR TONIGHT...GENERAL MVFR
WITH SCATTERED FLURRIES LOW LANDS AND MVFR/IFR SNOW SHOWERS
MOUNTAINS...ALONG WITH GUSTY WEST WINDS 15 TO 25 MPH BUT HIGHER
ON RIDGETOPS.
FOR MONDAY. HIGH PRESSURE BUILDS IN FROM THE WEST WITH SLOWLY
DIMINISHING WINDS. CLOUDS WILL ALSO BE DECREASING FROM WEST TO
EAST...VFR WEST OF A CKB-CRW LINE BY 18Z. BUT CONTINUED MVFR /IFR
MOUNTAINS IN SCATTERED SNOW SHOWERS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z MONDAY...
FORECAST CONFIDENCE: MEDIUM
ALTERNATE SCENARIO: TIMING OF LOWER CIGS AND WIND GUSTS WILL VARY.
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 18 19 20 21 22 23 00 01 02 03 04 05
EST 1HRLY 13 14 15 16 17 18 19 20 21 22 23 00
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY M H M 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 L M M H H M M M M M M M
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H M H H H H H H H H
AFTER 18Z MONDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED AT THIS TIME.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/TRM
NEAR TERM...TRM/JMV
SHORT TERM...JSH
LONG TERM...26
AVIATION...JMV
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1140 AM CST SUN JAN 4 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 309 AM CST SUN JAN 4 2015
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A NORTHERN STREAM TROUGH OVER SOUTH CENTRAL CANADA INTO NORTH
DAKOTA...A SOUTHERN STREAM TROUGH FROM THE CENTRAL PLAINS INTO
ILLINOIS..AND RIDGES ON BOTH COASTS OF THE U.S.. ALSO OF NOTE WERE A
POTENT SHORTWAVE IN MO AND IL WITH A WEAKER SHORTWAVE MOVING THROUGH
THE FORECAST AREA. THIS LATTER SHORTWAVE IN CONJUNCTION WITH MID
LEVEL FRONTOGENESIS HAS SUPPORTED A BAND OF SNOW ACROSS MUCH OF THE
FORECAST AREA. SEE THE LATEST MKEPNSARX FOR UPDATED SNOWFALL
AMOUNTS THROUGH THE MORNING. ANY PRECIPITATION WITH THE POTENT
SHORTWAVE HAS STAYED SOUTH OF THE FORECAST AREA. HOWEVER...WE ARE
FEELING ITS EFFECTS IN THE WIND DEPARTMENT...AS THAT POTENT
SHORTWAVE HAS HELPED TO DEEPEN A SURFACE LOW NOW OVER LOWER MI.
NORTHWEST WINDS HAVE BEEN GUSTING IN THE 20-40 MPH RANGE...HIGHEST
WEST OF U.S. HIGHWAY 52. THESE WINDS ARE ADVECTING ARCTIC AIR INTO
THE REGION FROM THE NORTHERN STREAM UPPER TROUGH IN SOUTH CENTRAL
CANADA. 925MB TEMPS PER RAP ANALYSIS HAVE FALLEN TO -5C SOUTHEAST
TO -15C NORTHWEST ACROSS THE FORECAST AREA...WITH SURFACE
TEMPERATURES FROM THE MID TEENS SOUTHEAST TO UPPER SINGLE DIGITS
NORTHWEST. MEANWHILE...MUCH COLDER -20 TO -24C 925MB AIR WAS
LURKING ACROSS THE EASTERN DAKOTAS AND WESTERN MN...AND AROUND
-30C UNDER THE UPPER TROUGH. READINGS ARE WELL BELOW ZERO UNDER
THIS COLDER AIR.
THE MID LEVEL FRONTOGENETICAL BAND OF SNOW CURRENTLY OVER THE
FORECAST AREA SHOULD MOVE OFF TO THE EAST QUICKLY THIS MORNING...IN
RESPONSE TO THE SHORTWAVE OVER THE AREA MARCHING EAST. MOST MODEL
GUIDANCE SUGGESTS BY 15Z THE SNOW SHOULD HAVE PUSHED OFF TO THE
EAST...WITH MAYBE SOME LINGERING FLURRIES OVER WI UNTIL 18Z. THE
REST OF THE SHORT TERM PERIOD IS DRY AS SUBSIDENCE AND DRY ARCTIC
AIR MOVE IN.
ATTENTION THEN TURNS TO TEMPERATURES/WIND CHILLS AS ARCTIC AIR POURS
INTO THE REGION...IN RESPONSE TO THE UPPER TROUGH OVER SOUTH CENTRAL
CANADA CROSSING THE FORECAST AREA. 925MB TEMPS FALL TO -20 TO -24C
BY 00Z AND -23 TO -27C BY 12Z MONDAY. THIS ADVECTION OF ARCTIC AIR
COMBINED WITH A 15 TO 25 MPH SUSTAINED WIND SPEED TODAY CAUSES WIND
CHILLS TO EVENTUALLY FALL INTO ADVISORY CRITERIA / LESS THAN 20
BELOW ZERO / EVERYWHERE BY SUNSET. FURTHER COOLING TAKES PLACE
TONIGHT TO PUT TAYLOR AND CLARK INTO WARNING CRITERIA / 35 BELOW
ZERO. PORTIONS OF SOUTHEAST MN COULD GET CLOSE TO WARNING AS
WELL.
REGARDING HAZARDS. CONSIDERED WAITING UNTIL 15Z...THE EXPIRATION
TIME OF THE WINTER WEATHER ADVISORY FOR OUR WESTERN 10 COUNTIES...TO
START HOISTING THE WIND CHILL ADVISORIES. HOWEVER...GIVEN THE REST
OF THE FORECAST AREA IS SEEING WIND CHILL ADVISORY CRITERIA
TODAY...AND ALL NEIGHBORING FORECAST OFFICES ALSO HOISTING
ADVISORIES...HAVE ISSUED THE ADVISORIES NOW. HAVE ALSO UPGRADED THE
WATCH FOR TAYLOR/CLARK TO A WARNING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 309 AM CST SUN JAN 4 2015
THE ARCTIC AIR OVER THE REGION TO START MONDAY MODIFIES QUITE A BIT
THROUGH THE DAY...REFLECTED BY 925MB TEMPS CLIMBING TO -18 TO -21C
BY 00Z. THIS MODIFICATION ALLOWS OUR WIND CHILLS TO MOSTLY GET ABOVE
ADVISORY CRITERIA BY 18Z...WHICH IS THE END TIME FOR THE HAZARDS.
SOME EXTENSION PAST 18Z COULD BE REQUIRED FOR A FEW AREAS.
HOWEVER...THE IMPROVEMENT IN WIND CHILLS COMES AT THE EXPENSE OF
SNOW MOVING INTO THE REGION DURING THE AFTERNOON.
04.00Z MODEL GUIDANCE CONTINUES TO DEPICT A FAST MOVING POTENT
SHORTWAVE...CURRENTLY IN THE GULF OF ALASKA...TRACKING FROM CENTRAL
MONTANA AT 18Z MONDAY TO EASTERN IOWA BY 06Z TUESDAY. THIS IS A
DISTANCE OF 925 MILES...RESULTING IN A 77 MPH AVERAGE SPEED FOR THE
SHORTWAVE. THE COMBINATION OF DPVA FROM THE SHORTWAVE...DIVERGENCE
FROM THE LEFT EXIT REGION OF AN UPPER JET AND STRONG MID LEVEL
FRONTOGENESIS...WILL LEAD TO A BROAD SWATH OF SNOW ON THE ORDER OF
300 MILE WIDTH. CONTAINED WITHIN THAT SWATH WILL BE A SMALLER...
HEAVIER BAND ON THE ORDER OF 100 MILE WIDTH PER MODEL CONSENSUS.
LIQUID EQUIVALENT AMOUNTS COULD BE AS HIGH AS 0.5 INCH AS SUGGESTED
BY THE NAM/GFS AND SOME SREF MEMBERS. WITH A DEEP EFFECTIVE
DENDRITIC GROWTH OF 300MB...THAT COULD RESULT IN 8 TO 12 INCHES OF
SNOWFALL...MUCH OF WHICH FALLING WITHIN IN A 9 HOUR WINDOW. THE
SERIOUS PROBLEM IN FORECASTING THESE HIGH AMOUNTS IS PLACEMENT. THE
BOUNDS SEEMS TO BE THE SOUTHERN PORTION OF THE FORECAST AREA PER THE
04.00Z NAM AND ALONG I-80 PER THE 04.00Z GFS. GIVEN THIS LARGE
PLACEMENT ISSUE...CANNOT FORECAST THE HIGHER AMOUNTS YET.
HOWEVER...THE WINTER STORM WATCH IS VERY MUCH WARRANTED...THOUGH
LATER SHIFTS MAY BE ABLE TO TRIM OFF THE NORTHERN SIDE OF THE WATCH.
REGARDING PRECIPITATION CHANCES...HAVE INCREASED THEM QUITE A BIT
FOR MONDAY AFTERNOON GIVEN FASTER TIMING...ALONG WITH MORE OF A
DECREASE FOR OVERNIGHT MONDAY NIGHT.
ATTENTION THEN TURNS BACK TO THE ARCTIC COLD AS A SHORTWAVE TROUGH
CURRENTLY OVER BAFFIN ISLAND DROPS SOUTH ACROSS THE AREA TUESDAY
NIGHT AND WEDNESDAY. THIS SHOT OF ARCTIC AIR LOOKS NASTY AS 925MB
TEMPS FALL FROM -14C TO -18C AT 12Z TUESDAY...TO -18 TO -21C AT 00Z
WEDNESDAY...TO -26C TO -28C BY 12Z WEDNESDAY AND HOLDING IN THE -24
TO -28C RANGE FOR MUCH OF WEDNESDAY. TEMPERATURES SHOULD PLUMMET
WELL BELOW ZERO FOR TUESDAY NIGHT AND STAY BELOW ZERO ON WEDNESDAY.
IN FACT...MEX GUIDANCE SUGGESTS SOME LOCATIONS ON WEDNESDAY MAY NOT
CLIMB ABOVE -10. ADD INTO THIS A BRISK NORTHWEST WIND INDUCED BY
925MB WINDS IN THE 35-45 KT RANGE COMING ACROSS TUESDAY NIGHT AND
WEDNESDAY...THIS IS A PERFECT RECIPE FOR WIND CHILLS TO DROP TO NEAR
OR INTO WARNING CRITERIA EVERYWHERE. IT MAY NOT BE UNTIL SOMETIME
THURSDAY WHEN WE FINALLY GET OUT OF ADVISORY CRITERIA.
A BRIEF WARM UP IS PROGGED THURSDAY IN RESPONSE TO WARM ADVECTION
AHEAD OF ANOTHER POTENT SHORTWAVE DROPPING SOUTH INTO MN. THIS WARM
ADVECTION LOOKS TO INDUCE SOME LIGHT SNOW OVER THE NORTHEAST HALF OF
THE FORECAST AREA. HAVE RAISED PRECIPITATION CHANCES TO 30-40 AND
MAY NEED FURTHER INCREASES. IN THE WAKE OF THE SHORTWAVE...ANOTHER
ARCTIC AIRMASS DROPS IN...SIMILAR TO THE ONE FOR TONIGHT. MORE WIND
CHILL HEADLINES ARE LIKELY. FOLLOWED A MODEL CONSENSUS FOR HIGHS
FRIDAY AND LOWS THURSDAY NIGHT THROUGH FRIDAY NIGHT...BUT THESE MAY
NEED TO BE LOWERED 3-5 DEGREES.
AS WE HEAD INTO THE WEEKEND...THE HIGH LATITUDE BLOCKING PATTERN
ACROSS THE PACIFIC INTO WESTERN NORTH AMERICA FINALLY BREAKS DOWN.
THIS WILL ALLOW FOR A MODERATING TREND ACROSS THE FORECAST
AREA...GETTING TEMPERATURES BACK UP TO NEAR NORMAL BY MONDAY NEXT
WEEK. HOWEVER...IT APPEARS ACCOMPANYING THE WARM ADVECTION COULD BE
SOME LIGHT SNOW FOR LATE SATURDAY INTO SATURDAY NIGHT PER 04.00Z
ECMWF.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1140 AM CST SUN JAN 4 2015
MAIN TAF CONCERNS ARE DIMINISHING WINDS AFTER 00Z MONDAY. LATEST 17Z
SURFACE ANALYSIS SHOWS COLD FRONT OVER MICHIGAN AND HIGH PRESSURE
OVER THE NORTHERN PLAINS. TIGHT PRESSURE GRADIENT IN BETWEEN THE
COLD FRONT AND HIGH PRESSURE ARE PRODUCING WINDS SPEEDS OF 15 TO 25
KNOTS WITH GUSTS 25 TO 30 KNOTS ACROSS SOUTHEAST MINNESOTA AND
SOUTHWEST WISCONSIN PER LATEST 17Z METARS. LATEST RST METARS SHOW
MVFR VISIBILITY DUE TO BLOWING SNOW. HOWEVER...COORDINATING WITH
TOWER...THE VISIBILITY AT THE SENSOR SITE IS NOT REPRESENTATIVE
OF THE AIRPORT FIELD AND HAVE INTRODUCED VFR CONDITIONS AT RST
TAF SITE THROUGH THE REST OF THIS AFTERNOON. HIGH PRESSURE BUILDS
INTO THE REGION AFTER 00Z MONDAY...AS GRADIENT RELAXES AND WINDS
WILL DIMINISH TO 10 KNOTS OR LESS AT BOTH RST AND LSE TAF SITES BY
04-05Z MONDAY. VFR CONDITIONS WILL PREVAIL THROUGH REST OF THE
TAF PERIOD.
NEXT AVIATION CONCERN IS SYSTEM MOVING ACROSS IOWA MONDAY AFTERNOON
INTO TUESDAY MORNING. THIS WILL MOST LIKELY PRODUCE IFR TO MVFR
CONDITIONS AT LSE AND RST TAF SITES...AS CEILINGS LOWER AND
VISIBILITIES ARE REDUCED...DUE TO MOISTURE ADVECTING AND LIGHT
SNOW MOVING INTO THE AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR WIZ032>034.
WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO NOON CST MONDAY
FOR WIZ041>044-053>055-061.
WINTER STORM WATCH FROM MONDAY EVENING THROUGH LATE MONDAY NIGHT
FOR WIZ053>055-061.
WIND CHILL WARNING UNTIL NOON CST MONDAY FOR WIZ017-029.
MN...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY
NIGHT FOR MNZ086-087-094>096.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR MNZ079-086>088-094-
095.
WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO NOON CST MONDAY
FOR MNZ096.
IA...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY
NIGHT FOR IAZ008>011-018-019-029-030.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR IAZ008-009-018-019.
WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO NOON CST MONDAY
FOR IAZ010-011-029-030.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DTJ