Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/19/14
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
948 AM MST FRI JAN 17 2014
.UPDATE...
&&
.SHORT TERM...CURRENT FORECASTS LOOK ON TRACK...WITH SOME MINOR
ADJUSTMENTS TO SKY COVER BASED ON CURRENT CONDITIONS. FAIRLY
STRONG NORTHWEST FLOW ALOFT TO GRADUALLY WEAKEN TODAY AS UPPER
RIDGE BUILDS INTO THE GREAT BASIN. WITH LOWER PRESSURE ACROSS
CENTRAL PLAINS STATES...GUSTY WINDS WILL CONTINUE IN AND NEAR
FOOTHILLS. SPEEDS TO BE MUCH LESS THAN PREVIOUS DAYS...WITH SOME
GUSTS AROUND 40 MPH IN WIND PRONE AREAS. DOWNSLOPE WINDS WILL
HELP WARM TEMPERATURES...ESPECIALLY NEAR THE FOOTHILLS. THERE MAY
BE A BIT OF A WAVE CLOUD ALONG THE FOOTHILLS DURING THE AFTERNOON
AS NOTED BY THE SYNTHETIC SATELLITE IMAGERY WHICH MAY DELAY THE
WARMUP A BIT.
.AVIATION...LIGHT SOUTHERLY WINDS CURRENTLY AT AREA AIRPORTS.
BEGINNING TO SEE WESTERLY WINDS NEAR THE FOOTHILLS WHICH SHOULD
SPREAD ACROSS THE AREA BY 19Z. CURRENT TAFS SHOWING THIS TREND AND
SEEMS REASONABLE. WILL CONTINUE FOR THE UPCOMING ISSUANCE. LATEST
RAP AND HRRR INDICATE WINDS AT KDEN AND KAPA BECOMING EASTERLY
BY 21Z. NOT SURE IF THIS WILL OCCUR DUE TO THE EXPECTED WESTERLY
PUSH...BUT WILL CONTINUE TO MONITOR. DRAINAGE TO THEN PREVAIL BY
03Z. VFR CONTINUING WITH UNLIMITED CEILINGS.
&&
.PREV DISCUSSION... /ISSUED 355 AM MST FRI JAN 17 2014/
..CORRECTION FOR THE PURPOSE OF CLARIFICATION
SHORT TERM...STRONG DEEP LAYER NORTH-NORTHWEST FLOW OVER THE
WESTERN GREAT PLAINS...WHICH INCLUDES EASTERN COLORADO...WILL
CONTINUE TO SHIFT EAST TODAY AS THE PERSISTENT UPPER LEVEL RIDGE
ALONG THE WEST COAST BEGINS ITS EASTWARD MIGRATION OVER THE GREAT
BASIN. WARMING WILL BE SLOW AT FIRST WITH BANDS OF MID AND HIGH
CLOUDS RACING SOUTH OVER THE AREA THIS MORNING. BY THIS AFTERNOON
PRESSURE FALLS ON THE PLAINS WILL STIMULATE WESTERLY/DOWNSLOPE LOW-
LEVEL FLOW WHICH WILL HELP WARM TEMPERATURES ESPLY IN AND NEAR THE
FRONT RANGE FOOTHILLS. SHOULD SEE GUSTY CHINOOK WINDS DEVELOPING IN
THE FOOTHILLS THIS MORNING AND SPREADING ONTO THE NEARBY PLAINS
BEFORE MIDDAY. SPEEDS SHOULD REMAIN WELL BELOW THOSE OBSERVED OVER
THE PAST FEW DAYS...GENERALLY IN THE 15-30KT RANGE. HOWEVER FOR
THOSE AREAS PRONE TO HIGH WINDS SUCH AS AROUND NEDERLAND...
WONDERVU...ELDORADO CANYON...CLEAR CREEK AND COAL CREEK CANYONS AND
THE FOOTHILLS WEST OF BOULDER...COULD SEE WEST WINDS OCCASIONALLY
GUST TO AROUND 40 MPH. HIGHS TODAY WILL GENERALLY BE 3-6DEG F ABOVE
THOSE RECORDED YESTERDAY. ALTHOUGH BREEZY AREAS NEAR THE FOOTHILLS
MAY SEE HIGHS AS MUCH AS 10-12DEGS F WARMER. TONIGHT...WARMING WILL
CONTINUE WITH RISING GEOPOTENTIAL HEIGHTS UNDER GENERALLY CLEAR
SKIES. LOOK FOR A LIGHT DRAINAGE WIND PATTERN TO SET UP SOON AFTER
SUNSET WITH A FLAT PRESSURE GRADIENT ON THE PLAINS. AREAS IN AND
NEAR THE FOOTHILLS HOWEVER MAY CONTINUE TO EXPERIENCE GUSTY CHINOOK
WINDS WHICH WILL RESULT IN MILD OVERNIGHT TEMPERATURES.
LONG TERM...A DRY AND MILD PERIOD THROUGH THE MIDDLE OF NEXT WEEK
WITH HIGH AMPLITUDE RIDGE REMAINING AROUND THE WEST COAST. THE
RESULT OVER COLORADO WILL BE A DECREASING NORTHWEST FLOW PATTERN
THIS WEEKEND ALONG WITH A WARMING TREND FOR BOTH SATURDAY AND
SUNDAY. WARMEST DAY WILL BE SUNDAY WITH READINGS NEAR 60 ACROSS
LOWER ELEVATIONS WITH A VERY DRY AIRMASS IN PLACE. THERE WILL BE
SOME COOLING ON MONDAY AS A WEAK RIPPLE MOVES THROUGH THE FLOW BUT
NO PRECIP IS EXPECTED.
BY LATER NEXT WEEK...THERE IS A WAVE WHICH TRIES TO UNDERCUT THE
RIDGE LATE THURSDAY AND FRIDAY WITH COOLER TEMPERATURES AND
POSSIBLE A CHANCE OF PRECIP. THE GFS IS MORE PRONOUNCED WITH
HIGHER MOISTURE LEVELS WHILE EUROPEAN IS DRIER. THIS PERIOD IS
JUST BEYOND DAY 7 SO WILL ADDRESS THIS MORE IN NEXT UPDATE.
AVIATION...VFR CONDITIONS WILL PREVAIL DURING THE NEXT 24 HOURS.
THE STRONG NORTHERLY FLOW ALOFT OF THE PAST FEW DAYS WILL SHIFT
EAST OF THE AREA TODAY RESULTING IN LIGHTER WINDS...AND A RETURN
TO A MORE FAMILIAR WIND PATTERN WITH DRAINAGE FLOW AT NIGHT AND
EARLY IN THE MORNING...AND LIGHT UPSLOPE/UPVALLEY WINDS DURING THE
LATE MORNING AND AFTERNOON HOURS. HOWEVER...BJC NEAR THE FOOTHILLS
MAY STILL SEE PERIODS OF GUSTY WEST WINDS OF 15-25KTS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....ENTREKIN
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS ALBANY NY
337 PM EST FRI JAN 17 2014
.SYNOPSIS...
A STRONG UPPER LEVEL TROUGH WILL APPROACH THE REGION OVERNIGHT.
THIS WILL PROVIDE THE REGION WITH ANOTHER ROUND OF LIGHT SNOW
DURING THE DAY SATURDAY. ANOTHER DISTURBANCE WILL IMPACT THE
REGION SUNDAY WITH ADDITIONAL SNOW SHOWERS EXPECTED.
THEREAFTER...AN ARCTIC AIR MASS WILL SETTLE ACROSS THE ENTIRE
REGION FOR MOST OF THE UPCOMING WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
H2O VAPOR LOOP ANALYSIS REVEALS A HIGH AMPLITUDE FLOW WITH A RIDGE
OVER WESTERN NOAM...DEEP TROUGH EXTENDING FROM HUDSON BAY INTO THE
GULF OF MEXICO...AND A RIDGE OVER THE CENTRAL ATLANTIC OCEAN. A
CLOSER LOOK SHOWS A RATHER STRONG SHORT WAVE OVER THE OHIO VALLEY
WITH REGIONAL RADARS AT THIS TIME SUGGESTING MAINLY SCATTERED
SHOWERS IN THIS AREA. HOWEVER...ADDITIONAL UPPER SUPPORT WITH A
JET STREAM OVER THE MID ATLANTIC STATES WILL ADD ADDITIONAL
SUPPORT FOR MORE SHOWERS TO DEVELOP THIS EVENING. THESE SHOWERS
WILL EVENTUALLY MIGRATE FROM SOUTH TO NORTH WITH LIFT/OMEGA
INCREASING SOUTH OF I90 OVERNIGHT. THEREFORE...WE WILL SHOW A
GRADUAL INCREASE IN POPS TONIGHT ALONG WITH INCREASING CLOUD
COVER. AS FOR TEMPERATURES...WITH AMPLE BREAKS IN THE OVERCAST
TODAY AND CLOUDS EXPECTED TO INCREASE THIS EVENING...WE WILL SHADE
TOWARD THE WARMER SIDE OF THE GUIDANCE.
AS FOR ACCUMULATIONS OF SNOW...MOST VALUES ARE EXPECTED TO BE AN
INCH OR LESS.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
WE BEGIN THIS WEEKEND WITH MAINLY SNOW AS THE AFOREMENTIONED SHORT
WAVE APPROACHES AND MOVES ACROSS THE REGION. THE LATEST RUC13 AND
NCEP MODEL SUITE POINT TOWARD AN ENHANCED BAND OF SNOW LIFTING
FROM SOUTH TO NORTH DURING SATURDAY MORNING PER THE 850-700MB
OMEGA FIELDS. HOWEVER...THE MID LEVEL DRY SLOT ALSO QUICKLY
APPROACHES WHICH SHOULD CUT DOWN ON THE BEST ICE NUCLEI FOR BEST
SNOW FALL RATE POTENTIAL. IN FACT...BUFKIT PROFILES SUGGEST THE
BETTER LIFT WILL OCCUR OUTSIDE OF THE DENDRITIC ZONE SO SNOWFALL
RATES SHOULD REMAIN LOW. DURING THE DAY...THE SNOW WILL BECOME
MORE TERRAIN BASED AS THE UPPER LOW PASSES OVERHEAD AND THE MAIN
SURFACE LOW TRACKS FROM LONG ISLAND AND ACROSS CAPE COD. THE
BETTER DEFORMATION AXIS APPEARS TO REMAIN WEST OF OUR CWFA SO PER
COLLABORATION WITH NEIGHBORING OFFICES...WPC-WWD AND ENSEMBLE
PROBABILITIES...WE WILL WITHHOLD THE MENTION OF HEADLINES AT THIS
TIME AND WORD THE HWO ACCORDINGLY.
THIS SYSTEM WILL QUICKLY DEPART SATURDAY EVENING WITH A NARROW
SHORT WAVE RIDGE AXIS SLIDING OVERHEAD. WHILE MOST OF THE REGION
SHOULD REMAIN RATHER DRY...SOME LAKE EFFECT/ENHANCEMENT DOWNWIND
OF LAKE ONTARIO MAY BRING ADDITIONAL ACCUMULATING SNOWFALL ACROSS
PORTIONS OF THE ADIRONDACKS.
NEXT CLIPPER TYPE SYSTEM APPROACHES FOR SUNDAY WITH AN ADDITIONAL
CHANCE FOR SNOW SHOWERS. THE LAKE WILL CONTINUE TO CONTRIBUTE
ADDITIONAL LOW LEVEL MOISTURE FOR ADDITIONAL SNOWFALL ACROSS
PORTIONS OF THE DACKS BUT INLAND EXTENT AND SHEAR PROFILES SUGGEST
LESS THAN CONFIDENCE TO HOIST ANY HEADLINES AT THIS TIME. IT WILL
BECOME BRISK AS GRADIENT TIGHTENS UP WITH AFTERNOON HIGHS INTO THE
20S AND LOWER 30S.
SUNDAY NIGHT...ARCTIC BOUNDARY APPROACHES WITH ADDITIONAL SNOW
SHOWERS AND POSSIBLE SQUALLS AS LAPSE RATES AT AND BELOW H700
STEEPEN. FURTHERMORE...MIXING LAYER HEIGHTS TOO TAP INTO 30-40KTS
TO MAKE FOR A RATHER BRISK NIGHT. MODEL GUIDANCE ALSO HINTS AT
ANOTHER WAVE DEVELOPING ALONG THE ARCTIC BOUNDARY WHICH COULD
SERVE TO SLOW DOWN THE BOUNDARY ALONG WITH AN INCREASED CHANCE FOR
ACCUMULATING SNOWFALL.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
MUCH OF THE EXTENDED PERIOD WILL BE DOMINATED BY FRIGID...ARCTIC
AIR...WITH LITTLE PRECIPITATION EXPECTED.
AN ARCTIC COLD FRONT WILL PASS THROUGH THE REGION ON MONDAY FROM
NORTHWEST TO SOUTHEAST. SOME SCATTERED SNOW SHOWERS...SNOW
SQUALLS...AND FLURRIES WILL ACCOMPANY THIS BOUNDARY AS IT
CROSSES...ALTHOUGH SNOWFALL WILL BE MINOR DUE TO LIMITED MOISTURE.
MAX TEMPS ON MONDAY WILL RANGE FROM THE TEENS IN THE NW ADIRONDACKS
WHERE THE FRONT WILL BE CROSSING VERY EARLY IN THE DAY TO THE MID TO
UPPER 30S IN THE MID HUDSON VALLEY AND NW CT...WHERE THE FRONT WONT
CROSS TILL LATER IN THE AFTN.
BEHIND THE BOUNDARY...850 HPA TEMPS WILL DROP TO -20 TO -25 DEGREES
C FOR MONDAY NIGHT AND THEY WILL CONTINUE AT THIS LEVEL THROUGH THE
REMAINDER OF THE WEEK. IT WILL BE EXCEPTIONALLY DRY...WITH PWAT
VALUES LESS THAN 0.10 INCHES...WHICH IS WELL BELOW THE
CLIMATOLOGICAL NORMAL VALUES FOR MID TO LATE JANUARY. EXACTLY HOW
COLD IT GETS DURING THIS COLD OUTBREAK WILL DEPEND ON A FEW
FACTORS...SUCH AS HOW CALM THE WINDS CAN GET AT NIGHT AND WHERE
THERE IS FRESH AND DEEP SNOW PACK. FOR NOW...WE WILL FORECAST MAX
TEMPS FOR TUESDAY THROUGH FRIDAY GENERALLY IN THE LOW TO MID TEENS
FOR VALLEY AREAS /SINGLE DIGITS IN THE HIGH TERRAIN/...WITH 0 TO 5
AT NIGHT /BELOW ZERO ACROSS THE HILLS AND MOUNTAINS/. HOWEVER...IT/S
POSSIBLE ITS EVEN COLDER IF IT RADIATES WELL...ESP FOR TUESDAY AND
WED NIGHTS.
LATE IN THE WEEK...THE 12Z ECMWF SHOWS A CLIPPER MOVING ACROSS THE
AREA WITH A REINFORCING SHOT OF COLD AIR FOR THURSDAY NIGHT INTO
FRIDAY...WHICH COULD BRING SOME LIGHT SNOW TO THE REGION. THE ECMWF
HAS BEEN TOO AGGRESSIVE IN DEVELOPING STORMS LATELY...AND WE WILL
FAVOR THE FLATTER AND DRIER 12Z GFS...WHICH FITS WELL WITH THE
LATEST 12Z GEFS. MORE COLD AIR IS SHOWN ON THE MODELS UPSTREAM
ACROSS CENTRAL CANADA...SO IT APPEARS THAT THE BELOW NORMAL TEMPS
WILL CONTINUE INTO NEXT WEEKEND AND FOR THE LATTER PORTION OF THE
MONTH AS WELL.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
VFR FLYING CONDITIONS WILL PREVAIL AT THE TAF SITES THIS AFTERNOON
AND THROUGH MOST OF TONIGHT...BEFORE SNOW SHOWERS ACCOMPANYING A
WEAK AREA OF LOW PRESSURE BRING MVFR CONDITIONS SATURDAY.
THIS AFTERNOON...AFTER AN IFR/MVFR START AT THE TAF SITES THIS
MORNING...VFR FLYING CONDITIONS HAVE RETURNED WITH OCCASIONAL
SCATTERED TO BROKEN STRATOCUMULUS AROUND 6-8 KFT EXPECTED THROUGH
THE REMAINDER OF THE AFTERNOON AT KGFL AND KALB...WITH ONLY FEW TO
SCATTERED STRATOCUMULUS EXPECTED AT KPSF AND KPOU AS WEAK HIGH
PRESSURE BUILDS ACROSS THE REGION. SOUTHERLY WINDS WILL GENERALLY BE
AROUND 5-10 KNOTS.
TONIGHT INTO SATURDAY...AN UPPER-LEVEL DISTURBANCE WILL APPROACH
FROM THE GREAT LAKES REGION HELPING TO DEVELOP A WEAK AREA OF LOW
PRESSURE AT THE SURFACE. AHEAD OF THIS FEATURE THIS EVENING...SKIES
WILL BECOME SCATTERED TO MOSTLY CLEAR FOR A BRIEF PERIOD AS THE HIGH
PRESSURE EXITS TO THE EAST BEFORE INCREASED LOW AND MIDLEVEL
MOISTURE BRINGS A RETURN OF GRADUALLY LOWERING AND THICKENING CLOUDS
DURING THE OVERNIGHT.
SCATTERED LIGHT SNOW SHOWERS WILL BEGIN TO OVERSPREAD THE TAF SITES
FROM SOUTH TO NORTH AFTER 09Z...WITH LIGHT ACCUMULATIONS EXPECTED.
THERE MAY EVEN BE A BRIEF PERIOD OF RAIN MIXED IN WITH THE SNOW AT
KALB AND KPOU AFTER 15Z AND HAVE HIGHLIGHTED THIS POTENTIAL WITH
PROB30 GROUPS AT THIS TIME. WINDS WILL BE LIGHT AND VARIABLE TONIGHT
BEFORE BECOMING SOUTHEASTERLY DURING THE DAY SATURDAY AROUND 5-8
KNOTS.
OUTLOOK...
SATURDAY: HIGH OPERATIONAL IMPACT. LIKELY SN.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. SLIGHT CHANCE OF
SHSN.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SUNDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. SLIGHT CHANCE OF SHSN.
MARTIN LUTHER KING JR DAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF
SHSN.
MONDAY NIGHT TO TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
RIVER AND STREAM LEVELS CONTINUE TO EXHIBIT A SLOW DECLINE FROM
THE RECENT RAINFALL AND SNOW MELT. THROUGH EARLY NEXT WEEK...ONLY
LIGHT PRECIPITATION IN THE FORM OF SNOW IS EXPECTED ACROSS OUR
AREA. THIS PRECIP WILL HAVE LITTLE EFFECT ON AREA RIVERS AND
STREAMS. AS A RESULT...STREAM FLOWS SHOULD GRADUALLY LOWER. COLD
TEMPERATURES RETURNING LATER THIS WEEKEND AND ESPECIALLY NEXT
WEEK...RIVER AND LAKE ICE WILL BEGIN TO REFORM AND STRENGTHEN ONCE
AGAIN.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM
NEAR TERM...BGM
SHORT TERM...BGM
LONG TERM...FRUGIS
AVIATION...IRL
HYDROLOGY...BGM
FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS ALBANY NY
916 AM EST FRI JAN 17 2014
.SYNOPSIS...
CLOUDS WILL INCREASE TODAY...AS ANOTHER FAST MOVING
CLIPPER STORM APPROACHES FROM THE GREAT LAKES AND OHIO VALLEY
REGION. THIS SYSTEM WILL MOVE ACROSS OUR REGION LATE TONIGHT INTO
SATURDAY WITH A PERIOD SNOW FOR MUCH OF THE AREA. ADDITIONAL FAST
MOVING STORM SYSTEMS WILL MOVE ACROSS THE REGION SUNDAY INTO NEXT
WEEK...EACH BRINGING A CHANCE OF SNOW SHOWERS ALONG WITH MUCH COLDER
AIR ARRIVING NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 916 AM EST...AN AREA OF LOW PRESSURE IS LIFTING FROM THE
GREAT LAKES TOWARDS SOUTHERN CANADA. A SURFACE TROUGH ATTACHED TO
THIS LOW PRESSURE AREA IS ALLOWING FOR SOME LIGHT SNOW SHOWERS
ACROSS THE ADIRONDACKS THIS MORNING. THE NEW 12Z NAM12 AND LATEST
12Z 3KM HRRR ALL SHOW LIGHT PRECIP LIFTING NORTH OVER THE NEXT FEW
HOURS AND ENDING BY NOON ACROSS THAT AREA. ELSEWHERE...IT WILL BE
DRY...ALTHOUGH PLENTY OF CLOUD COVER LOOKS TO REMAIN IN PLACE
THROUGH MUCH OF THE MORNING HOURS...ALTHOUGH SOME BREAKS ARE
ALREADY STARTING TO OCCUR ACROSS NW CT AND SW MASS.
SOME MORE BREAKS IN SUN MAY OCCUR BY AFTN FOR THE HUDSON VALLEY
AND INTO SOUTHERN VT. OTHERWISE...SKIES WILL GENERALLY BE MOSTLY
CLOUDY ACROSS THE REGION AS A SFC COLD FRONT BEGINS TO APPROACH
FROM THE GREAT LAKES REGION.
NEUTRAL TEMPERATURE ADVECTION WILL STILL RESULT IN RATHER MILD
READINGS TODAY. EXPECTING MAX TEMPERATURES MAINLY IN UPPER 30S TO
LOWER 40S IN MOST VALLEY LOCATIONS WITH LOWER TO MID 30S OVER THE
HIGHER TERRAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
TRANQUIL WEATHER IS EXPECTED TO START THE NIGHT...HOWEVER A COMPACT
BUT VIGOROUS SHORT WAVE TROUGH AND VORT MAX WILL BE RAPIDLY
APPROACHING FROM THE OHIO VALLEY AND WILL SPAWN A WEAK SURFACE LOW
OVER OUR AREA ON SATURDAY. IT WILL BE MOSTLY CLOUDY TONIGHT WITH LOW
TEMPERATURES WELL ABOVE NORMAL.
LARGE SCALE ASCENT AHEAD OF THE THIS SYSTEM LOOKS TO BE RATHER
SUBSTANTIAL...ALTHOUGH IT WILL BE FAST-MOVING. SNOW SHOULD DEVELOP
SOUTH AND WEST OF THE CAPITAL REGION SHORTLY BEFORE DAYBREAK
SATURDAY...SPREADING NORTHEASTWARD ACROSS THE REST OF THE AREA
DURING THE MORNING AND EARLY AFTERNOON. MODELS IN GENERALLY GOOD
AGREEMENT WITH THIS SYSTEM...ALTHOUGH SOME OF THE SUBTLE FEATURES
SUCH AS AREAS OF HIGHEST QPF ARE SLIGHTLY DIFFERENT. BASED ON
OPERATIONAL MODELS AND ENSEMBLE SPREAD...WE ARE GENERALLY EXPECTING
BETWEEN ONE AND TWO TENTHS OF QPF. SNOW RATIOS GREATEST OVER THE
HIGHER TERRAIN AROUND 12 OR 13 TO 1...WITH LOWER THAN CLIMATOLOGY
VALUES EXPECTED IN THE VALLEYS AROUND 10 OR 11 TO 1 DUE TO
RELATIVELY WARM TEMP PROFILE. THIS RESULTS IN FORECAST SNOWFALL OF
MAINLY 1-3 INCHES ACROSS THE AREA...AGAIN WITH THE GREATER AMOUNTS
IN THE HIGHER TERRAIN. THERE COULD BE SOME LOCALLY HIGHER AMOUNTS
WHERE ANY MESOSCALE BANDS OR BANDLETS SET UP...AS THERE MAY BE
ENOUGH FRONTOGENESIS TO BRIEFLY PRODUCE BANDING. AT TIMES WHEN
PRECIP IS LIGHTER...SOME RAIN MAY EVEN MIX IN AT VALLEY FLOORS BUT
THE MAJORITY SHOULD FALL AS SNOW.
THE SYSTEM QUICKLY EXITS INTO NEW ENGLAND BY LATE SATURDAY
AFTERNOON OR EARLY EVENING...ALTHOUGH THERE COULD STILL BE SOME
WRAP-AROUND SNOW SHOWERS LINGERING INTO THE EVENING ESPECIALLY
ACROSS THE HIGHER TERRAIN AREAS. WE SHOULD THEN GET A BRIEF DRY
PERIOD SATURDAY NIGHT...AS A SMALL-SCALE SURFACE RIDGE BUILDS INTO
THE AREA. THE NEXT SYSTEM WILL ALREADY BY ON OUR DOORSTEP EARLY
SUNDAY...AS ANOTHER FAST-MOVING SHORT WAVE TROUGH APPROACHES FROM
THE WEST. THIS SHOULD RESULT IN ADDITIONAL SNOW SHOWER
ACTIVITY...WITH SOME MINOR ACCUMULATIONS POSSIBLE. BEST CHANCE
WILL BE OVER THE HIGHER TERRAIN NORTH AND WEST OF ALBANY. THERMAL
PROFILE IS COOLER COMPARED TO SATURDAY...SO MAX TEMPS WILL BE
CLOSER TO NORMAL FOR MID JANUARY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AFTER THE ARCTIC COLD FRONT MOVES THROUGH THE REGION SUNDAY NIGHT OR
EARLY MONDAY MORNING...ACCOMPANIED BY SCT SNOW SHOWERS AND POSSIBLY
SOME SNOW SQUALLS...EXPECT MAINLY DRY AND BITTERLY COLD CONDITIONS
MONDAY NIGHT THROUGH THURSDAY. MODELS GENERALLY KEEP ANY SURFACE OR
UPPER LEVEL TROFS TO THE SOUTH OF THE REGION AS THEY ROTATE AROUND
THE MAIN LONG WAVE TROF OVER THE EASTERN UNITED STATES. IN
ADDITION...THE LOW LEVEL FLOW WILL BE TOO NORTHERLY FOR ANY LAKE
ENHANCEMENT IN THE ALBANY FORECAST AREA.
THE MAIN WEATHER ISSUE DURING THIS PERIOD WILL BE THE COLD. BY
MONDAY NIGHT WIND CHILL VALUES COULD REACH ADVISORY LEVELS IN THE
ADIRONDACK ZONES...THEN ACROSS MOST OF THE FORECAST AREA DURING THE
REST OF THE WEEK. COLDEST TEMPS AND WIND CHILLS WILL BE WEDNESDAY
INTO THURSDAY AND THE AVERAGE FORECAST TEMPS FOR ALBANY DO LOWER TO
10 DEGREES F STARTING ON WEDNESDAY. TOO EARLY TO INITIATE ANY ACTION
WITH THE EMERGENCY MANAGERS AT THIS TIME...BUT WILL HIGHLIGHT THE
COLD IN THE HWOALY PRODUCT.
AS THE FRONT MOVES THROUGH SUNDAY NIGHT...TEMPS WILL VARY WIDELY
FROM NORTH TO SOUTH...WITH LOWS IN THE ADIRONDACKS IN THE SINGLE
DIGITS...BUT AROUND 20 OVER SOUTHERN AREAS. HIGHS MONDAY WILL BE IN
THE TEENS AND 20S...THEN TEMPS NOSEDIVE. LOWS MONDAY NIGHT WILL BE
IN THE ZERO TO 10 BELOW RANGE OVER THE ADIRONDACKS...AND THE SINGLE
DIGITS TO LOW TEENS ELSEWHERE. HIGHS TUESDAY WILL BE IN THE SINGLE
DIGITS AND TEENS. LOWS TUESDAY AND WEDNESDAY NIGHTS WILL BE 5 BELOW
TO 15 BELOW ZERO IN THE ADIRONDACKS...AND 5 BELOW TO AROUND 5 ABOVE
ELSEWHERE. HIGHS WEDNESDAY WILL BE IN THE SINGLE DIGITS AND
TEENS...AND SOME PLACES IN THE ADIRONDACKS MAY NEVER GET ABOVE ZERO.
ON THURSDAY HIGHS WILL BE 5 ABOVE TO AROUND 20.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
EXCEPT FOR LEFTOVER MVFR/IFR CIGS/VSBYS AT THE KGFL/KPOU/KALB/KPSF
TAF SITES DUE TO FOG AND LOW CLOUDS THROUGH 13Z/14Z...EXPECT VFR
CONDITIONS AT THE TAF SITES THROUGH THE END OF THE TAF PERIOD AT 12Z
SATURDAY. MOISTURE TO THE WEST OF THE HUDSON VALLEY WILL MOVE OVER
THE REGION LATER THIS MORNING...BUT THE CLOUDS ASSOCIATED WITH THIS
MOISTURE ARE GENERALLY IN THE 5000 TO 8000 FOOT RANGE. THIS EVENING
THESE CLOUDS WILL BECOME SCT...BUT THEN CLOUDS WILL INCREASE AGAIN
LATE TONIGHT AS THE NEXT WEAK LOW PRESSURE AREA MOVES NORTHEAST
THROUGH PENNSYLVANIA.
WINDS WILL GENERALLY BE CALM OR LIGHT AND VARIABLE EARLY THIS
MORNING...BUT AS THE SURFACE HIGH SHIFTS TO THE EAST...A SOUTHERLY
FLOW OF AIR WILL TAKE CONTROL AND EXPECT SOUTHERLY WINDS AT THE TAF
SITES AT LESS THAN 10 MPH FOR THE REST OF THE DAY. AFTER SUNSET...
WINDS WILL BECOME LIGHT AND VARIABLE.
OUTLOOK...
SATURDAY: HIGH OPERATIONAL IMPACT. LIKELY SN.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. SLIGHT CHANCE OF
SHSN.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SUNDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. SLIGHT CHANCE OF SHSN.
MARTIN LUTHER KING JR DAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF
SHSN.
MONDAY NIGHT TO TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
RIVER AND STREAM LEVELS REMAIN SOMEWHAT ELEVATED DUE TO THE RECENT
RAINFALL AND SNOW MELT...BUT HAVE BEEN RECEDING FOR THE PAST COUPLE
DAYS. THROUGH EARLY NEXT WEEK...ONLY LIGHT PRECIPITATION IN THE FORM
OF SNOW IS EXPECTED ACROSS OUR AREA. THIS PRECIP WILL HAVE LITTLE
EFFECT ON AREA RIVERS AND STREAMS. AS A RESULT...STREAM FLOWS SHOULD
GRADUALLY LOWER. WITH COLD TEMPERATURES RETURNING OVER THE WEEKEND
AND ESPECIALLY NEXT WEEK...RIVER AND LAKE ICE WILL BEGIN TO REFORM
AND STRENGTHEN.
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.
&&
.EQUIPMENT...
THE COMMUNICATIONS ISSUES WITH THE KENX WSR-88D HAVE BEEN
RESOLVED AND THE RADAR IS BACK IN SERVICE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS/JPV
NEAR TERM...FRUGIS/JPV
SHORT TERM...JPV
LONG TERM...GJM
AVIATION...GJM
HYDROLOGY...FRUGIS/JPV
EQUIPMENT...FRUGIS
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1032 PM EST SAT JAN 18 2014
.SYNOPSIS...
AN APPROACHING COLD FRONT WILL MOVE THROUGH THE FORECAST AREA EARLY
SUNDAY. A PRESSURE RIDGE WILL BE SOUTH OF THE AREA SUNDAY THROUGH
MONDAY. ANOTHER COLD FRONT WILL SWEEP THROUGH THE AREA TUESDAY.
ARCTIC HIGH PRESSURE BEHIND THIS FRONT WILL DOMINATE WEDNESDAY
THROUGH FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
THE APPROACHING COLD FRONT WILL BE NEAR THE FORECAST AREA TOWARD
SUNRISE. LATEST HRRR INDICATES SOME PRECIPITATION ASSOCIATED WITH
THE FRONT MAY MOVE INTO THE AREA JUST BEFORE SUNRISE...BUT THINK
THE AIRMASS IS TOO DRY...AND LATEST MET GUIDANCE INDICATING POPS
LESS THAN 20 PERCENT. THIS APPEARS REASONABLE BECAUSE OF THE
PRESSURE RIDGE SOUTH OF THE AREA CONTINUING TO LIMIT MOISTURE
AHEAD OF THE FRONT. MIXING AND CLOUDINESS SHOULD HELP HOLD UP
TEMPERATURES TONIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/...
FURTHER DRYING WILL OCCUR BEHIND THE COLD FRONT SUNDAY MORNING. IT
WILL BE BREEZY. THE NAM BUFKIT MOMENTUM TRANSFER TOOL SUPPORTS GUSTS
NEAR 25 KNOTS. A LAKE WIND ADVISORY MAY BE NEEDED. THE SURFACE RIDGE
SOUTH OF THE AREA WILL CONTINUE TO MAINTAIN A DRY WESTERLY FLOW WITH
LITTLE MOISTURE RECOVERY AHEAD OF THE NEXT COLD FRONT APPROACHING
MONDAY. THE TEMPERATURE GUIDANCE WAS CLOSE. WARMING AHEAD OF THE
COLD FRONT WILL SUPPORT ABOVE NORMAL HIGH TEMPERATURES MONDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
THE GFS AND ECMWF MAINTAIN UPPER-LEVEL TROUGHING OVER THE EASTERN
PART OF THE NATION DURING THE MEDIUM-RANGE PERIOD. THE MODELS
INDICATE LITTLE MOISTURE ASSOCIATED WITH REINFORCING COLD FRONTS
TUESDAY AND THURSDAY. THE GFS...ECMWF...AND EKD MOS SUPPORT NEAR
NORMAL TEMPERATURES TUESDAY DURING THE TIME OF FRONTAL PASSAGE. THE
GUIDANCE INDICATES MUCH BELOW NORMAL TEMPERATURES DURING THE REST
OF THE PERIOD.
&&
.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
HIGH CONFIDENCE IN VFR CONDITIONS THROUGH THE TAF PERIOD.
RIDGE OF HIGH PRESSURE CURRENTLY CENTERED OVER THE REGION WILL
RETREAT SOUTHWARD THIS EVENING AS ANOTHER COLD FRONT APPROACHES
FROM THE WEST THEN CROSSES THE AREA TOWARD DAYBREAK SUNDAY
MORNING. WINDS SUBSIDING EARLY THIS EVENING TO SOUTHWEST 5 TO 10
KNOTS. WEST WINDS BECOMING GUSTY AGAIN SUNDAY MORNING. AS THE
COLD FRONT PASSES THERE WILL BE MAINLY MID LEVEL CLOUDS.
EXTENDED AVIATION OUTLOOK...BREEZY CONDITIONS POSSIBLE AT TIMES
THROUGH THURSDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
616 PM EST SAT JAN 18 2014
.SYNOPSIS...
AN APPROACHING COLD FRONT WILL MOVE THROUGH THE FORECAST AREA LATE
TONIGHT AND EARLY SUNDAY. A PRESSURE RIDGE WILL BE SOUTH OF THE AREA
SUNDAY THROUGH MONDAY. ANOTHER COLD FRONT WILL SWEEP THROUGH THE
AREA TUESDAY. ARCTIC HIGH PRESSURE BEHIND THIS FRONT WILL DOMINATE
WEDNESDAY THROUGH FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
THE APPROACHING COLD FRONT WILL BE NEAR THE FORECAST AREA TOWARD
SUNRISE. LATEST HRRR INDICATES SHOWERS ASSOCIATED WITH THE FRONT
WILL DISSIPATE BEFORE GETTING OVER THE MOUNTAINS. ALL OF THE GFS
AND NAM MOS GIVE POPS LESS THAN 20 PERCENT AND THIS APPEARS
REASONABLE BECAUSE OF THE PRESSURE RIDGE SOUTH OF THE AREA
CONTINUING TO LIMIT MOISTURE AHEAD OF THE FRONT. MIXING AND
CLOUDINESS SHOULD HELP HOLD UP TEMPERATURES TONIGHT. LEANED
TOWARD THE WARMER TEMPERATURE GUIDANCE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/...
FURTHER DRYING WILL OCCUR BEHIND THE COLD FRONT SUNDAY MORNING. IT
WILL BE BREEZY. THE NAM BUFKIT MOMENTUM TRANSFER TOOL SUPPORTS GUSTS
NEAR 25 KNOTS. A LAKE WIND ADVISORY MAY BE NEEDED. THE SURFACE RIDGE
SOUTH OF THE AREA WILL CONTINUE TO MAINTAIN A DRY WESTERLY FLOW WITH
LITTLE MOISTURE RECOVERY AHEAD OF THE NEXT COLD FRONT APPROACHING
MONDAY. THE TEMPERATURE GUIDANCE WAS CLOSE. WARMING AHEAD OF THE
COLD FRONT WILL SUPPORT ABOVE NORMAL HIGH TEMPERATURES MONDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
THE GFS AND ECMWF MAINTAIN UPPER-LEVEL TROUGHING OVER THE EASTERN
PART OF THE NATION DURING THE MEDIUM-RANGE PERIOD. THE MODELS
INDICATE LITTLE MOISTURE ASSOCIATED WITH REINFORCING COLD FRONTS
TUESDAY AND THURSDAY. THE GFS...ECMWF...AND EKD MOS SUPPORT NEAR
NORMAL TEMPERATURES TUESDAY DURING THE TIME OF FRONTAL PASSAGE. THE
GUIDANCE INDICATES MUCH BELOW NORMAL TEMPERATURES DURING THE REST
OF THE PERIOD.
&&
.AVIATION /23Z SATURDAY THROUGH THURSDAY/...
HIGH CONFIDENCE IN VFR CONDITIONS THROUGH THE TAF PERIOD.
RIDGE OF HIGH PRESSURE CURRENTLY CENTERED OVER THE REGION WILL
RETREAT SOUTHWARD THIS EVENING AS ANOTHER COLD FRONT APPROACHES
FROM THE WEST THEN CROSSES THE AREA TOWARD DAYBREAK SUNDAY
MORNING. WINDS SUBSIDING EARLY THIS EVENING TO SOUTHWEST 5 TO 10
KNOTS. WEST WINDS BECOMING GUSTY AGAIN SUNDAY MORNING. AS THE
COLD FRONT PASSES THERE WILL BE MAINLY MID LEVEL CLOUDS.
EXTENDED AVIATION OUTLOOK...BREEZY CONDITIONS POSSIBLE AT TIMES
THROUGH THURSDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
923 PM CST SAT JAN 18 2014
.DISCUSSION...
923 PM CST
LATE EVENING UPDATE...
ALL WINTER HEADLINES HAVE EXPIRED OR BEEN CANCELLED THIS EVENING AS
SHORT-WAVE DISTURBANCE RESPONSIBLE FOR EARLIER SNOW MOVES OFF INTO
INDIANA AND OHIO OVERNIGHT.
SUBSIDENCE IN THE WAKE OF THIS FEATURE HAS ERODED CLOUD COVER OVER A
LARGE PORTION OF THE FORECAST AREA AS OF 9 PM CST...WHICH ALONG WITH
LIGHT WINDS ASSOCIATED WITH COL AREA NORTH OF SFC LOW HAS ALLOWED
SOME PATCHY SHALLOW FOG TO DEVELOP ACROSS PARTS OF THE CHICAGO METRO
AND NORTHWEST INDIANA. FOG SHOULD NOT LAST TOO LONG...AS WINDS BACK
TO THE WEST-NORTHWEST AND INCREASE A BIT BY MIDNIGHT OR SO WHICH
SHOULD ALLOW FOR ENOUGH MIXING TO DISSIPATE IT. THOSE SAME
CLEAR/CALM WIND CONDITIONS OVER OUR NEW SNOW COVER WERE ALSO
ALLOWING TEMPS TO DROP OFF QUICKLY ACROSS THE AREA...WITH SOME
SINGLE DIGIT READINGS ALREADY IN OUR TYPICALLY GOOD RADIATIONAL
COOLING SPOTS ACROSS NORTH CENTRAL IL AND THE FOX VALLEY AREA. HAVE
LOWERED MINS A BIT ACROSS NORTHERN IL OVERNIGHT...WITH TEMP TREND IN
HOURLY GRIDS ACTUALLY STABILIZING OR COMING BACK UP A BIT AFTER
MIDNIGHT WITH DEVELOPMENT OF AFOREMENTIONED WIND/MIXING.
OTHERWISE...NO OTHER SIGNIFICANT CHANGES TO GOING FORECAST.
RATZER
&&
.PREV DISCUSSION...
228 PM CST
REST OF TODAY...
SURFACE LOW IS DIVING SOUTHEAST INTO WEST CENTRAL ILLINOIS THIS
AFTERNOON WITH A NARROW BAND OF MODERATE TO HEAVY SNOW STRETCHING
ACROSS NORTH CENTRAL ILLINOIS INTO NORTHWEST INDIANA. SYSTEM HAS
BEEN FAIRLY WELL BEHAVED SO FAR WITH REPORTS OF AROUND 3-4 INCHES IN
THE AREAS THAT HAVE SEEN THE MOST SNOW THUS FAR. DECENT PACKING OF
THE PRESSURE IS NOTED ON THE 280-285K THETA SURFACES...WITH THE BEST
ASCENT PROGGED TO GRADUALLY SHIFT SOUTHEAST OUT OF THE CWA BY MID
EVENING. RAP H7 F-GEN SEEMS TO INITIALIZE NICELY...LINING UP WELL
WITH RADAR AND STRETCHING FROM THE SOUTH SUBURBS INTO NORTHWEST
INDIANA...AND PIVOTING TO THE EAST OUT OF THE AREA. THE RAP DOES
PICK UP ON F-GEN RESTRENGTHENING THIS EVENING OVER A SIMILAR AREA
AND GRADUALLY SINKING SOUTH ACROSS THE REMAINDER OF THE CWA BY LATE
THIS EVENING. WITH THIS IN MIND...DID SLOW DOWN THE TIMING OF SNOW
ENDING THIS EVENING IN THE GRIDS BY A FEW HOURS.
TONIGHT THROUGH SUNDAY...
THE POTENT UPPER WAVE THAT IMPACTED THE AREA TODAY WILL DEPART
ACROSS THE OHIO VALLEY THIS EVENING AND TONIGHT WITH MID/UPPER
RIDGING BUILDING INTO THE UPPER MIDWEST AND WESTERN LAKES REGION.
STRONG SFC PRESSURE RISES WILL MOVE IN BEHIND THE QUICKLY DEPARTING
LOW AND IS EXPECTED TO LEAD TO BREEZY CONDITIONS THIS
EVENING...MAINLY SOUTH OF I-80. FAIRLY STRONG HEIGHT RISES ALOFT
WILL ALSO OVERSPREAD THE AREA...PERSISTING THROUGH THE DAY SUNDAY
AND SHOULD PROVIDE A BRIEF RESPITE IN THE PRECIPITATION. ONCE THE
SURFACE/LOW LEVEL RIDGE AXIS PASSES OVER THE AREA LATE
TONIGHT...WINDS WILL BACK TO THE SOUTHWEST AND WARMER AIR WILL
ADVECT OVERHEAD...WITH H85 TEMPS RISING TO AROUND 2-3C BY SUNDAY
MORNING. SURFACE TEMPERATURES SHOULD REBOUND TO NEAR THE FREEZING
MARK DURING THE DAY SUNDAY...OTHERWISE SHOULD BE A QUIET WEATHER DAY
TOMORROW.
MONDAY THROUGH TUESDAY ...
MAIN CONCERN AS WE HEAD INTO NEXT WEEK WILL BE THE RETURN OF COLD
ARCTIC AIR. WEST COAST RIDGE IS PROGGED TO AMPLIFY OVER THE
WEEKEND...STRETCHING NORTH ACROSS ALASKA WHICH IN COMBINATION WITH A
DEEPENING LOW OVER ONTARIO WILL DISLODGE AIR FROM THE ARCTIC SOUTH
INTO THE NORTHERN LAKES REGION SUNDAY INTO MONDAY. THE LEADING EDGE
OF THIS COLD AIRMASS WILL SINK SOUTH BEHIND A COLD FRONT THAT WILL
PASS SOUTH OVER THE AREA EARLY MONDAY. TEMPERATURES BEHIND THE FRONT
ARE EXPECTED TO BE FALLING THROUGH THE DAY MONDAY. H85 TEMPS ARE
EXPECTED TO FALL TO AROUND -20C AND GENERALLY PERSIST THROUGH THE
END OF THE WEEK. STEEP LOW LEVEL LAPSE RATES DEVELOP BEHIND THE
FRONT AND APPEARS FAVORABLE FOR COLD AIR CU WITH SOME FLURRIES
DEVELOPING IF NOT A FEW SNOW SHOWERS. ACROSS NORTHWEST
INDIANA...WILL ALSO HAVE TO KEEP AN EYE ON THE LAKE EFFECT MACHINE
WHICH WILL BE RAMPING UP...AND APPEARS VERY FAVORABLE TO SEE SOME
SIGNIFICANT SNOW ACCUMULATIONS IN OR NEAR OUR EASTERN COUNTIES.
OVER LAND...LAPSE RATES WEAKEN MONDAY NIGHT AND APPEARS THAT WE
SHOULD BE WELL ENTRENCHED IN THE COLD/DRY AIR TUESDAY LEADING TO
MOST AREAS STAYING DRY OUTSIDE OF THE LAKE EFFECT.
WEDNESDAY THROUGH FRIDAY...
REGION REMAINS UNDER AN ACTIVE NORTHWEST FLOW PATTERN THROUGH THE
END OF NEXT WEEK RESULTING IN SEVERAL PERIODS OF SNOWFALL AS WAVES
ROTATE ACROSS THE AREA. MODELS HAVE BEEN TRENDING TOWARDS A MORE
ROBUST UPPER WAVE DROPPING ACROSS THE REGION MIDWEEK. SHOULD THIS
PAN OUT...MIGHT SEE A BRIEF/MODEST WARMUP AHEAD OF THE SYSTEM...BUT
THEN EVEN COLDER AIR SPILLING BEHIND. BOTH GEM AND ECMWF INDICATE
TEMPS FALLING TO AROUND -24C AT H85 WEDNESDAY. WHILE ITS PROBABLY A
BIT FAR OUT TO START TALKING LOW TRACK AND POTENTIAL SNOW...FOR NOW
AT LEAST MODELS INDICATE THE LOW WILL STAY NORTH OF THE CWA.
TEMPERATURES SHOULD REMAIN WELL BELOW NORMAL WEDNESDAY AND
THURSDAY...AND ARE EXPECTED TO BEGIN TO MODERATE SOME BY FRIDAY.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* LOW MVFR CIGS SHIFTING TO THE SOUTHEAST LATE THIS EVENING/EARLY
TONIGHT.
* GUSTY SOUTHWEST WINDS EXPECTED SUNDAY MORNING INTO EARLY SUNDAY
AFTERNOON...25-30 KT POSSIBLE.
MDB
//DISCUSSION...UPDATED 03Z...
BAND OF LOW MVFR CIGS IN THE 1000-1200 FT RANGE HAS DEVELOPED JUST
INLAND OF LAKE MICHIGAN OVER NORTHEAST ILLINOIS AND HAS BEGUN TO
AFFECT THE CHICAGO AREA TERMINALS. WITH WINDS IN THIS CLOUD
BEARING LAYER TURNING NORTHWESTERLY AND STRENGTHENING OVER THE
NEXT FEW HOURS EXPECT THE CURRENT SOUTHWESTWARD MOVEMENT TO SHIFT
TO A SOUTHEAST MOVEMENT LATE THIS EVENING. THIS WILL DRAG THE
CLOUD BAND SOUTHEAST AND OUT ORD/MDW...WITH A PERIOD OF BKN CIGS
LOOKING LIKELY AT DPA AS THE BAND SHIFTS SOUTHEAST. GYY SHOULD SEE
THESE LOWER CIGS ARRIVE IN THE NEXT HOUR OR LESS THEN PERSIST INTO
THE EARLY OVERNIGHT HOURS. OTHERWISE...LIGHT WINDS IN A WEAK
PRESSURE GRADIENT NORTH OF THE PASSING LOW...ALONG WITH COOLING
TEMPS ACROSS AREAS EXPERIENCING CLEAR SKIES...HAVE ALLOWED SOME
SHALLOW FOG TO DEVELOP BUT REPORTS INDICATE THAT PREVAILING
VISIBILITY IS IN THE 6 TO 9 MILE RANGE FOR THE MOST PART.
FROM 00Z...
LOW PRESSURE CENTERED NEAR KBMI/KDEC AREA CONTINUES TO MOVE
EASTWARD THIS EVENING WITH AN UPPER TROUGH AXIS SWINGING ACROSS
THE AREA AS WELL. ASSOCIATED AREA OF SNOW CONTINUES TO TRANSITION
TO THE SOUTH AND EAST AS WELL WITH THE TERMINALS SEEING IMPROVED
CONDITIONS OVERALL...THOUGH GYY WILL LIKELY SEE STEADIER SNOW A
BIT LONGER. WITH RADAR SHOWING A DECREASING TREND IN SNOW OVER AND
TO THE NORTH OF THE CHICAGO TERMINALS EXPECT THAT THERE WILL BE
VARIABLE VSBY BETWEEN 2 AND 5SM WITH PERIODS OF SNOW OVER THE
NEXT FEW HOURS BEFORE SNOW ENDS. CIGS HAVE BECOME VARIABLE AS WELL
WITH MUCH IMPROVED BASES OVER SEVERAL HOURS AGO. EXPECT THAT A MIX
OF MVFR/VFR WILL CONTINUE WITH THE SNOW IN THE AREA BUT THEN
BECOME MAINLY VFR TOWARD MID EVENING AS SNOW DEPARTS. SATELLITE
IMAGERY SHOWS SIGNIFICANT CLEARING UPSTREAM OF THE AREA SO HAVE
IMPROVED AND SCATTERED CIGS INTO THE OVERNIGHT. WITH THE LOW
PASSING TO THE SOUTH WINDS WILL SHIFT FROM NORTHEAST TO NORTH-
NORTHWEST OVER THE NEXT FEW HOURS...WITH SPEEDS UNDER 10 KT AS THE
PRESSURE GRADIENT NORTH OF THE LOW WEAKENS. A FURTHER SHIFT TO
WEST AND SOUTHWEST WILL OCCUR OVERNIGHT.
EXPECT VFR SUNDAY BUT SOUTHWEST WINDS LOOK TO RAMP UP DURING THE
MORNING. GUSTS MAY PUSH 30 KT FROM LATE MORNING THROUGH EARLY
AFTERNOON BEFORE SPEEDS EASE LATER IN THE DAY. WINDS JUST ABOVE
THE SURFACE WILL BE INCREASING AS WELL WITH 55-60 KT POSSIBLE NEAR
2000 FT AGL. THIS MAY RESULT IN SOME LOW LEVEL WIND SHEAR BUT WILL
LEAVE MENTION OUT OF THE TAF FOR NOW. IT COULD BE THAT HIGHER
SURFACE GUSTS RESULT WITH ENOUGH MIXING SO WILL NEED TO MONITOR
FOR ANY UPWARD ADJUSTMENTS.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH CONFIDENCE IN LOWER MVFR CIGS OVER THE NEXT FEW HOURS BUT
LOW-MEDIUM CONFIDENCE IN HOW QUICKLY THEY WILL CLEAR.
* MEDIUM-HIGH CONFIDENCE IN MAGNITUDE OF WINDS SUNDAY.
MDB
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...CHANCE SNOW SHOWERS...MVFR POSSIBLE.
TUESDAY...MAINLY VFR.
WEDNESDAY THROUGH FRIDAY...PERIODIC CHANCE FOR SNOW SHOWERS AND
MVFR. OTHERWISE VFR.
MDB
&&
.MARINE...
307 PM CST
NO CHANGES WERE MADE TO THE ONGOING HEADLINES AS GALES ARE STILL
EXPECTED.
THE LOW IS OVER THE MID MISSISSIPPI RIVER VALLEY AND WHILE IT IS
FILLING SLOWER THAN PREVIOUSLY EXPECTED...IT IS STILL EXPECTED TO
FILL AS MOVES ACROSS SOUTHERN IL. A SECOND LOW IS MOVING INTO
NORTHERN QUEBEC AND ITS COLD FRONT WILL SINK SOUTH DOWN THE LAKE
SUNDAY AND SUNDAY NIGHT. AS THE GRADIENT TIGHTENS
TONIGHT...SOUTHWEST WINDS INCREASE TO GALES OVER THE NORTHERN HALF
TO THE LAKE. WINDS TURN WEST ACROSS THE LAKE AND INCREASE TO LOW END
GALES BY SUNDAY MORNING. WINDS DIMINISH SUNDAY AFTERNOON...AND MAY
COME DOWN BEFORE THE END OF THE GALE WARNING.
WINDS THEN TURN NORTH BEHIND THE FRONT SUNDAY NIGHT AND REMAIN AT 20
TO 25 KT...POSSIBLY UP TO 30 KT AT TIMES...THROUGH MONDAY NIGHT.
HIGH PRESSURE MOVES OVER THE UPPER PLAINS MONDAY NIGHT AND SLIDES
SOUTHEAST REACHING THE SE US WEDNESDAY. WINDS DIMINISH TUESDAY AND
BECOME WEST. GUIDANCE DIFFERS IN REGARDS TO THE PATTERN MID NEXT
WEEK. THE ECMWF FEATURES A DEEP LOW OVER THE LAKE WHILE THE GFS HAS
A WEAK SURFACE TROUGH. BOTH DO FEATURE A HIGH MOVING OVER THE
PLAINS. SO HAVE WINDS BECOMING NORTHWEST AND/OR NORTH WEDNESDAY
NIGHT...AND IF THE LOW IS DEEPER...WINDS COULD BE STRONGER. AS THE
HIGH PASSES TO THE SOUTH LATE NEXT WEEK...WINDS WEAKEN AND BECOME
WEST.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...3 AM SUNDAY TO 9
AM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745...9 AM SUNDAY TO 4 PM SUNDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868 UNTIL 3 PM SUNDAY.
GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 AM SUNDAY TO 3 PM
SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...3 AM SUNDAY TO 10
PM SUNDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
902 PM CST SAT JAN 18 2014
.DISCUSSION...
645 PM CST
EARLY EVENING UPDATE...
SNOW CONTINUES TO DIMINISH/END FROM THE NORTHWEST EARLY THIS EVENING
AS MID-LEVEL SHORT WAVE TRACKS SOUTHEAST ACROSS THE REGION. RADAR
TRENDS INDICATE F-GEN BANDING HAS WEAKENED AND DECREASED IN COVERAGE
OVER EASTERN CWA LAST FEW HOURS...AND EXPECT THIS TREND TO CONTINUE
THROUGH MID-EVENING WITH RAP TRENDS TAKING STRONGER F-GEN BAND OFF
INTO CENTRAL INDIANA. HAVE ALLOWED WESTERN PORTION OF WINTER WEATHER
ADVISORY TO EXPIRE AS SCHEDULED AT 6 PM...WITH EASTERN PORTION
CONTINUING THROUGH 9 PM WITH LIGHT/ISOLATED MODERATE SNOW CONTINUING
AT THIS TIME THOUGH ONLY EXPECT PERHAPS AN ADDITIONAL INCH WHERE
HEAVIER BANDED ELEMENTS LINGER.
OTHERWISE...FORECAST REMAINS ESSENTIALLY ON TRACK WITH PARTIAL
CLEARING ALREADY DEVELOPING ACROSS NORTHWEST IL IN SUBSIDENCE BEHIND
STOUT SHORT WAVE.
RATZER
//PREV DISCUSSION...
228 PM CST
REST OF TODAY...
SURFACE LOW IS DIVING SOUTHEAST INTO WEST CENTRAL ILLINOIS THIS
AFTERNOON WITH A NARROW BAND OF MODERATE TO HEAVY SNOW STRETCHING
ACROSS NORTH CENTRAL ILLINOIS INTO NORTHWEST INDIANA. SYSTEM HAS
BEEN FAIRLY WELL BEHAVED SO FAR WITH REPORTS OF AROUND 3-4 INCHES IN
THE AREAS THAT HAVE SEEN THE MOST SNOW THUS FAR. DECENT PACKING OF
THE PRESSURE IS NOTED ON THE 280-285K THETA SURFACES...WITH THE BEST
ASCENT PROGGED TO GRADUALLY SHIFT SOUTHEAST OUT OF THE CWA BY MID
EVENING. RAP H7 F-GEN SEEMS TO INITIALIZE NICELY...LINING UP WELL
WITH RADAR AND STRETCHING FROM THE SOUTH SUBURBS INTO NORTHWEST
INDIANA...AND PIVOTING TO THE EAST OUT OF THE AREA. THE RAP DOES
PICK UP ON F-GEN RESTRENGTHENING THIS EVENING OVER A SIMILAR AREA
AND GRADUALLY SINKING SOUTH ACROSS THE REMAINDER OF THE CWA BY LATE
THIS EVENING. WITH THIS IN MIND...DID SLOW DOWN THE TIMING OF SNOW
ENDING THIS EVENING IN THE GRIDS BY A FEW HOURS.
TONIGHT THROUGH SUNDAY...
THE POTENT UPPER WAVE THAT IMPACTED THE AREA TODAY WILL DEPART
ACROSS THE OHIO VALLEY THIS EVENING AND TONIGHT WITH MID/UPPER
RIDGING BUILDING INTO THE UPPER MIDWEST AND WESTERN LAKES REGION.
STRONG SFC PRESSURE RISES WILL MOVE IN BEHIND THE QUICKLY DEPARTING
LOW AND IS EXPECTED TO LEAD TO BREEZY CONDITIONS THIS
EVENING...MAINLY SOUTH OF I-80. FAIRLY STRONG HEIGHT RISES ALOFT
WILL ALSO OVERSPREAD THE AREA...PERSISTING THROUGH THE DAY SUNDAY
AND SHOULD PROVIDE A BRIEF RESPITE IN THE PRECIPITATION. ONCE THE
SURFACE/LOW LEVEL RIDGE AXIS PASSES OVER THE AREA LATE
TONIGHT...WINDS WILL BACK TO THE SOUTHWEST AND WARMER AIR WILL
ADVECT OVERHEAD...WITH H85 TEMPS RISING TO AROUND 2-3C BY SUNDAY
MORNING. SURFACE TEMPERATURES SHOULD REBOUND TO NEAR THE FREEZING
MARK DURING THE DAY SUNDAY...OTHERWISE SHOULD BE A QUIET WEATHER DAY
TOMORROW.
MONDAY THROUGH TUESDAY ...
MAIN CONCERN AS WE HEAD INTO NEXT WEEK WILL BE THE RETURN OF COLD
ARCTIC AIR. WEST COAST RIDGE IS PROGGED TO AMPLIFY OVER THE
WEEKEND...STRETCHING NORTH ACROSS ALASKA WHICH IN COMBINATION WITH A
DEEPENING LOW OVER ONTARIO WILL DISLODGE AIR FROM THE ARCTIC SOUTH
INTO THE NORTHERN LAKES REGION SUNDAY INTO MONDAY. THE LEADING EDGE
OF THIS COLD AIRMASS WILL SINK SOUTH BEHIND A COLD FRONT THAT WILL
PASS SOUTH OVER THE AREA EARLY MONDAY. TEMPERATURES BEHIND THE FRONT
ARE EXPECTED TO BE FALLING THROUGH THE DAY MONDAY. H85 TEMPS ARE
EXPECTED TO FALL TO AROUND -20C AND GENERALLY PERSIST THROUGH THE
END OF THE WEEK. STEEP LOW LEVEL LAPSE RATES DEVELOP BEHIND THE
FRONT AND APPEARS FAVORABLE FOR COLD AIR CU WITH SOME FLURRIES
DEVELOPING IF NOT A FEW SNOW SHOWERS. ACROSS NORTHWEST
INDIANA...WILL ALSO HAVE TO KEEP AN EYE ON THE LAKE EFFECT MACHINE
WHICH WILL BE RAMPING UP...AND APPEARS VERY FAVORABLE TO SEE SOME
SIGNIFICANT SNOW ACCUMULATIONS IN OR NEAR OUR EASTERN COUNTIES.
OVER LAND...LAPSE RATES WEAKEN MONDAY NIGHT AND APPEARS THAT WE
SHOULD BE WELL ENTRENCHED IN THE COLD/DRY AIR TUESDAY LEADING TO
MOST AREAS STAYING DRY OUTSIDE OF THE LAKE EFFECT.
WEDNESDAY THROUGH FRIDAY...
REGION REMAINS UNDER AN ACTIVE NORTHWEST FLOW PATTERN THROUGH THE
END OF NEXT WEEK RESULTING IN SEVERAL PERIODS OF SNOWFALL AS WAVES
ROTATE ACROSS THE AREA. MODELS HAVE BEEN TRENDING TOWARDS A MORE
ROBUST UPPER WAVE DROPPING ACROSS THE REGION MIDWEEK. SHOULD THIS
PAN OUT...MIGHT SEE A BRIEF/MODEST WARMUP AHEAD OF THE SYSTEM...BUT
THEN EVEN COLDER AIR SPILLING BEHIND. BOTH GEM AND ECMWF INDICATE
TEMPS FALLING TO AROUND -24C AT H85 WEDNESDAY. WHILE ITS PROBABLY A
BIT FAR OUT TO START TALKING LOW TRACK AND POTENTIAL SNOW...FOR NOW
AT LEAST MODELS INDICATE THE LOW WILL STAY NORTH OF THE CWA.
TEMPERATURES SHOULD REMAIN WELL BELOW NORMAL WEDNESDAY AND
THURSDAY...AND ARE EXPECTED TO BEGIN TO MODERATE SOME BY FRIDAY.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* LOW MVFR CIGS SHIFTING TO THE SOUTHEAST LATE THIS EVENING/EARLY
TONIGHT.
* GUSTY SOUTHWEST WINDS EXPECTED SUNDAY MORNING INTO EARLY SUNDAY
AFTERNOON...25-30 KT POSSIBLE.
MDB
//DISCUSSION...UPDATED 03Z...
BAND OF LOW MVFR CIGS IN THE 1000-1200 FT RANGE HAS DEVELOPED JUST
INLAND OF LAKE MICHIGAN OVER NORTHEAST ILLINOIS AND HAS BEGUN TO
AFFECT THE CHICAGO AREA TERMINALS. WITH WINDS IN THIS CLOUD
BEARING LAYER TURNING NORTHWESTERLY AND STRENGTHENING OVER THE
NEXT FEW HOURS EXPECT THE CURRENT SOUTHWESTWARD MOVEMENT TO SHIFT
TO A SOUTHEAST MOVEMENT LATE THIS EVENING. THIS WILL DRAG THE
CLOUD BAND SOUTHEAST AND OUT ORD/MDW...WITH A PERIOD OF BKN CIGS
LOOKING LIKELY AT DPA AS THE BAND SHIFTS SOUTHEAST. GYY SHOULD SEE
THESE LOWER CIGS ARRIVE IN THE NEXT HOUR OR LESS THEN PERSIST INTO
THE EARLY OVERNIGHT HOURS. OTHERWISE...LIGHT WINDS IN A WEAK
PRESSURE GRADIENT NORTH OF THE PASSING LOW...ALONG WITH COOLING
TEMPS ACROSS AREAS EXPERIENCING CLEAR SKIES...HAVE ALLOWED SOME
SHALLOW FOG TO DEVELOP BUT REPORTS INDICATE THAT PREVAILING
VISIBILITY IS IN THE 6 TO 9 MILE RANGE FOR THE MOST PART.
FROM 00Z...
LOW PRESSURE CENTERED NEAR KBMI/KDEC AREA CONTINUES TO MOVE
EASTWARD THIS EVENING WITH AN UPPER TROUGH AXIS SWINGING ACROSS
THE AREA AS WELL. ASSOCIATED AREA OF SNOW CONTINUES TO TRANSITION
TO THE SOUTH AND EAST AS WELL WITH THE TERMINALS SEEING IMPROVED
CONDITIONS OVERALL...THOUGH GYY WILL LIKELY SEE STEADIER SNOW A
BIT LONGER. WITH RADAR SHOWING A DECREASING TREND IN SNOW OVER AND
TO THE NORTH OF THE CHICAGO TERMINALS EXPECT THAT THERE WILL BE
VARIABLE VSBY BETWEEN 2 AND 5SM WITH PERIODS OF SNOW OVER THE
NEXT FEW HOURS BEFORE SNOW ENDS. CIGS HAVE BECOME VARIABLE AS WELL
WITH MUCH IMPROVED BASES OVER SEVERAL HOURS AGO. EXPECT THAT A MIX
OF MVFR/VFR WILL CONTINUE WITH THE SNOW IN THE AREA BUT THEN
BECOME MAINLY VFR TOWARD MID EVENING AS SNOW DEPARTS. SATELLITE
IMAGERY SHOWS SIGNIFICANT CLEARING UPSTREAM OF THE AREA SO HAVE
IMPROVED AND SCATTERED CIGS INTO THE OVERNIGHT. WITH THE LOW
PASSING TO THE SOUTH WINDS WILL SHIFT FROM NORTHEAST TO NORTH-
NORTHWEST OVER THE NEXT FEW HOURS...WITH SPEEDS UNDER 10 KT AS THE
PRESSURE GRADIENT NORTH OF THE LOW WEAKENS. A FURTHER SHIFT TO
WEST AND SOUTHWEST WILL OCCUR OVERNIGHT.
EXPECT VFR SUNDAY BUT SOUTHWEST WINDS LOOK TO RAMP UP DURING THE
MORNING. GUSTS MAY PUSH 30 KT FROM LATE MORNING THROUGH EARLY
AFTERNOON BEFORE SPEEDS EASE LATER IN THE DAY. WINDS JUST ABOVE
THE SURFACE WILL BE INCREASING AS WELL WITH 55-60 KT POSSIBLE NEAR
2000 FT AGL. THIS MAY RESULT IN SOME LOW LEVEL WIND SHEAR BUT WILL
LEAVE MENTION OUT OF THE TAF FOR NOW. IT COULD BE THAT HIGHER
SURFACE GUSTS RESULT WITH ENOUGH MIXING SO WILL NEED TO MONITOR
FOR ANY UPWARD ADJUSTMENTS.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH CONFIDENCE IN LOWER MVFR CIGS OVER THE NEXT FEW HOURS BUT
LOW-MEDIUM CONFIDENCE IN HOW QUICKLY THEY WILL CLEAR.
* MEDIUM-HIGH CONFIDENCE IN MAGNITUDE OF WINDS SUNDAY.
MDB
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...CHANCE SNOW SHOWERS...MVFR POSSIBLE.
TUESDAY...MAINLY VFR.
WEDNESDAY THROUGH FRIDAY...PERIODIC CHANCE FOR SNOW SHOWERS AND
MVFR. OTHERWISE VFR.
MDB
&&
.MARINE...
307 PM CST
NO CHANGES WERE MADE TO THE ONGOING HEADLINES AS GALES ARE STILL
EXPECTED.
THE LOW IS OVER THE MID MISSISSIPPI RIVER VALLEY AND WHILE IT IS
FILLING SLOWER THAN PREVIOUSLY EXPECTED...IT IS STILL EXPECTED TO
FILL AS MOVES ACROSS SOUTHERN IL. A SECOND LOW IS MOVING INTO
NORTHERN QUEBEC AND ITS COLD FRONT WILL SINK SOUTH DOWN THE LAKE
SUNDAY AND SUNDAY NIGHT. AS THE GRADIENT TIGHTENS
TONIGHT...SOUTHWEST WINDS INCREASE TO GALES OVER THE NORTHERN HALF
TO THE LAKE. WINDS TURN WEST ACROSS THE LAKE AND INCREASE TO LOW END
GALES BY SUNDAY MORNING. WINDS DIMINISH SUNDAY AFTERNOON...AND MAY
COME DOWN BEFORE THE END OF THE GALE WARNING.
WINDS THEN TURN NORTH BEHIND THE FRONT SUNDAY NIGHT AND REMAIN AT 20
TO 25 KT...POSSIBLY UP TO 30 KT AT TIMES...THROUGH MONDAY NIGHT.
HIGH PRESSURE MOVES OVER THE UPPER PLAINS MONDAY NIGHT AND SLIDES
SOUTHEAST REACHING THE SE US WEDNESDAY. WINDS DIMINISH TUESDAY AND
BECOME WEST. GUIDANCE DIFFERS IN REGARDS TO THE PATTERN MID NEXT
WEEK. THE ECMWF FEATURES A DEEP LOW OVER THE LAKE WHILE THE GFS HAS
A WEAK SURFACE TROUGH. BOTH DO FEATURE A HIGH MOVING OVER THE
PLAINS. SO HAVE WINDS BECOMING NORTHWEST AND/OR NORTH WEDNESDAY
NIGHT...AND IF THE LOW IS DEEPER...WINDS COULD BE STRONGER. AS THE
HIGH PASSES TO THE SOUTH LATE NEXT WEEK...WINDS WEAKEN AND BECOME
WEST.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...3 AM SUNDAY TO 9
AM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745...9 AM SUNDAY TO 4 PM SUNDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868...MIDNIGHT SUNDAY TO 3 PM SUNDAY.
GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 AM SUNDAY TO 3 PM
SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...3 AM SUNDAY TO 10
PM SUNDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
645 PM CST SAT JAN 18 2014
.DISCUSSION...
645 PM CST
EARLY EVENING UPDATE...
SNOW CONTINUES TO DIMINISH/END FROM THE NORTHWEST EARLY THIS EVENING
AS MID-LEVEL SHORT WAVE TRACKS SOUTHEAST ACROSS THE REGION. RADAR
TRENDS INDICATE F-GEN BANDING HAS WEAKENED AND DECREASED IN COVERAGE
OVER EASTERN CWA LAST FEW HOURS...AND EXPECT THIS TREND TO CONTINUE
THROUGH MID-EVENING WITH RAP TRENDS TAKING STRONGER F-GEN BAND OFF
INTO CENTRAL INDIANA. HAVE ALLOWED WESTERN PORTION OF WINTER WEATHER
ADVISORY TO EXPIRE AS SCHEDULED AT 6 PM...WITH EASTERN PORTION
CONTINUING THROUGH 9 PM WITH LIGHT/ISOLATED MODERATE SNOW CONTINUING
AT THIS TIME THOUGH ONLY EXPECT PERHAPS AN ADDITIONAL INCH WHERE
HEAVIER BANDED ELEMENTS LINGER.
OTHERWISE...FORECAST REMAINS ESSENTIALLY ON TRACK WITH PARTIAL
CLEARING ALREADY DEVELOPING ACROSS NORTHWEST IL IN SUBSIDENCE BEHIND
STOUT SHORT WAVE.
RATZER
&&
.PREV DISCUSSION...
228 PM CST
REST OF TODAY...
SURFACE LOW IS DIVING SOUTHEAST INTO WEST CENTRAL ILLINOIS THIS
AFTERNOON WITH A NARROW BAND OF MODERATE TO HEAVY SNOW STRETCHING
ACROSS NORTH CENTRAL ILLINOIS INTO NORTHWEST INDIANA. SYSTEM HAS
BEEN FAIRLY WELL BEHAVED SO FAR WITH REPORTS OF AROUND 3-4 INCHES IN
THE AREAS THAT HAVE SEEN THE MOST SNOW THUS FAR. DECENT PACKING OF
THE PRESSURE IS NOTED ON THE 280-285K THETA SURFACES...WITH THE BEST
ASCENT PROGGED TO GRADUALLY SHIFT SOUTHEAST OUT OF THE CWA BY MID
EVENING. RAP H7 F-GEN SEEMS TO INITIALIZE NICELY...LINING UP WELL
WITH RADAR AND STRETCHING FROM THE SOUTH SUBURBS INTO NORTHWEST
INDIANA...AND PIVOTING TO THE EAST OUT OF THE AREA. THE RAP DOES
PICK UP ON F-GEN RESTRENGTHENING THIS EVENING OVER A SIMILAR AREA
AND GRADUALLY SINKING SOUTH ACROSS THE REMAINDER OF THE CWA BY LATE
THIS EVENING. WITH THIS IN MIND...DID SLOW DOWN THE TIMING OF SNOW
ENDING THIS EVENING IN THE GRIDS BY A FEW HOURS.
TONIGHT THROUGH SUNDAY...
THE POTENT UPPER WAVE THAT IMPACTED THE AREA TODAY WILL DEPART
ACROSS THE OHIO VALLEY THIS EVENING AND TONIGHT WITH MID/UPPER
RIDGING BUILDING INTO THE UPPER MIDWEST AND WESTERN LAKES REGION.
STRONG SFC PRESSURE RISES WILL MOVE IN BEHIND THE QUICKLY DEPARTING
LOW AND IS EXPECTED TO LEAD TO BREEZY CONDITIONS THIS
EVENING...MAINLY SOUTH OF I-80. FAIRLY STRONG HEIGHT RISES ALOFT
WILL ALSO OVERSPREAD THE AREA...PERSISTING THROUGH THE DAY SUNDAY
AND SHOULD PROVIDE A BRIEF RESPITE IN THE PRECIPITATION. ONCE THE
SURFACE/LOW LEVEL RIDGE AXIS PASSES OVER THE AREA LATE
TONIGHT...WINDS WILL BACK TO THE SOUTHWEST AND WARMER AIR WILL
ADVECT OVERHEAD...WITH H85 TEMPS RISING TO AROUND 2-3C BY SUNDAY
MORNING. SURFACE TEMPERATURES SHOULD REBOUND TO NEAR THE FREEZING
MARK DURING THE DAY SUNDAY...OTHERWISE SHOULD BE A QUIET WEATHER DAY
TOMORROW.
MONDAY THROUGH TUESDAY ...
MAIN CONCERN AS WE HEAD INTO NEXT WEEK WILL BE THE RETURN OF COLD
ARCTIC AIR. WEST COAST RIDGE IS PROGGED TO AMPLIFY OVER THE
WEEKEND...STRETCHING NORTH ACROSS ALASKA WHICH IN COMBINATION WITH A
DEEPENING LOW OVER ONTARIO WILL DISLODGE AIR FROM THE ARCTIC SOUTH
INTO THE NORTHERN LAKES REGION SUNDAY INTO MONDAY. THE LEADING EDGE
OF THIS COLD AIRMASS WILL SINK SOUTH BEHIND A COLD FRONT THAT WILL
PASS SOUTH OVER THE AREA EARLY MONDAY. TEMPERATURES BEHIND THE FRONT
ARE EXPECTED TO BE FALLING THROUGH THE DAY MONDAY. H85 TEMPS ARE
EXPECTED TO FALL TO AROUND -20C AND GENERALLY PERSIST THROUGH THE
END OF THE WEEK. STEEP LOW LEVEL LAPSE RATES DEVELOP BEHIND THE
FRONT AND APPEARS FAVORABLE FOR COLD AIR CU WITH SOME FLURRIES
DEVELOPING IF NOT A FEW SNOW SHOWERS. ACROSS NORTHWEST
INDIANA...WILL ALSO HAVE TO KEEP AN EYE ON THE LAKE EFFECT MACHINE
WHICH WILL BE RAMPING UP...AND APPEARS VERY FAVORABLE TO SEE SOME
SIGNIFICANT SNOW ACCUMULATIONS IN OR NEAR OUR EASTERN COUNTIES.
OVER LAND...LAPSE RATES WEAKEN MONDAY NIGHT AND APPEARS THAT WE
SHOULD BE WELL ENTRENCHED IN THE COLD/DRY AIR TUESDAY LEADING TO
MOST AREAS STAYING DRY OUTSIDE OF THE LAKE EFFECT.
WEDNESDAY THROUGH FRIDAY...
REGION REMAINS UNDER AN ACTIVE NORTHWEST FLOW PATTERN THROUGH THE
END OF NEXT WEEK RESULTING IN SEVERAL PERIODS OF SNOWFALL AS WAVES
ROTATE ACROSS THE AREA. MODELS HAVE BEEN TRENDING TOWARDS A MORE
ROBUST UPPER WAVE DROPPING ACROSS THE REGION MIDWEEK. SHOULD THIS
PAN OUT...MIGHT SEE A BRIEF/MODEST WARMUP AHEAD OF THE SYSTEM...BUT
THEN EVEN COLDER AIR SPILLING BEHIND. BOTH GEM AND ECMWF INDICATE
TEMPS FALLING TO AROUND -24C AT H85 WEDNESDAY. WHILE ITS PROBABLY A
BIT FAR OUT TO START TALKING LOW TRACK AND POTENTIAL SNOW...FOR NOW
AT LEAST MODELS INDICATE THE LOW WILL STAY NORTH OF THE CWA.
TEMPERATURES SHOULD REMAIN WELL BELOW NORMAL WEDNESDAY AND
THURSDAY...AND ARE EXPECTED TO BEGIN TO MODERATE SOME BY FRIDAY.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* LIGHT SNOW TAPERING OFF EARLY THIS EVENING...VARIABLE 2-5SM VSBY
POSSIBLE AS DIMINISHING SNOW SHOWERS PUSH ACROSS.
* VARIABLE MVFR/VFR CIGS EARLY THIS EVENING WITH SCATTERING LATE
THIS EVENING.
* EAST-NORTHEAST WINDS TURNING NORTH-NORTHWEST MID EVENING.
* GUSTY SOUTHWEST WINDS EXPECTED SUNDAY MORNING INTO EARLY SUNDAY
AFTERNOON...25-30 KT POSSIBLE.
MDB
//DISCUSSION...UPDATED 00Z...
LOW PRESSURE CENTERED NEAR KBMI/KDEC AREA CONTINUES TO MOVE
EASTWARD THIS EVENING WITH AN UPPER TROUGH AXIS SWINGING ACROSS
THE AREA AS WELL. ASSOCIATED AREA OF SNOW CONTINUES TO TRANSITION
TO THE SOUTH AND EAST AS WELL WITH THE TERMINALS SEEING IMPROVED
CONDITIONS OVERALL...THOUGH GYY WILL LIKELY SEE STEADIER SNOW A
BIT LONGER. WITH RADAR SHOWING A DECREASING TREND IN SNOW OVER AND
TO THE NORTH OF THE CHICAGO TERMINALS EXPECT THAT THERE WILL BE
VARIABLE VSBY BETWEEN 2 AND 5SM WITH PERIODS OF SNOW OVER THE
NEXT FEW HOURS BEFORE SNOW ENDS. CIGS HAVE BECOME VARIABLE AS WELL
WITH MUCH IMPROVED BASES OVER SEVERAL HOURS AGO. EXPECT THAT A MIX
OF MVFR/VFR WILL CONTINUE WITH THE SNOW IN THE AREA BUT THEN
BECOME MAINLY VFR TOWARD MID EVENING AS SNOW DEPARTS. SATELLITE
IMAGERY SHOWS SIGNIFICANT CLEARING UPSTREAM OF THE AREA SO HAVE
IMPROVED AND SCATTERED CIGS INTO THE OVERNIGHT. WITH THE LOW
PASSING TO THE SOUTH WINDS WILL SHIFT FROM NORTHEAST TO NORTH-
NORTHWEST OVER THE NEXT FEW HOURS...WITH SPEEDS UNDER 10 KT AS THE
PRESSURE GRADIENT NORTH OF THE LOW WEAKENS. A FURTHER SHIFT TO
WEST AND SOUTHWEST WILL OCCUR OVERNIGHT.
EXPECT VFR SUNDAY BUT SOUTHWEST WINDS LOOK TO RAMP UP DURING THE
MORNING. GUSTS MAY PUSH 30 KT FROM LATE MORNING THROUGH EARLY
AFTERNOON BEFORE SPEEDS EASE LATER IN THE DAY. WINDS JUST ABOVE
THE SURFACE WILL BE INCREASING AS WELL WITH 55-60 KT POSSIBLE NEAR
2000 FT AGL. THIS MAY RESULT IN SOME LOW LEVEL WIND SHEAR BUT WILL
LEAVE MENTION OUT OF THE TAF FOR NOW. IT COULD BE THAT HIGHER
SURFACE GUSTS RESULT WITH ENOUGH MIXING SO WILL NEED TO MONITOR
FOR ANY UPWARD ADJUSTMENTS.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH CONFIDENCE IN LIGHT SNOW TAPERING OFF THIS EVENING. HIGH
CONFIDENCE THAT THERE WILL BE VARIABLE VSBY AT TIMES...WITH
MEDIUM CONFIDENCE IN ENDING TIME OF SNOW.
* HIGH CONFIDENCE IN VARIABLE MVFR/VFR CIGS BECOMING
VFR/SCATTERING WITH TIME.
* HIGH CONFIDENCE IN WIND TRENDS THROUGH THE EVENING AND TIMING OF
SHIFT TO NORTH-NORTHWEST.
* MEDIUM-HIGH CONFIDENCE IN MAGNITUDE OF WINDS SUNDAY.
MDB
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...CHANCE SNOW SHOWERS...MVFR POSSIBLE.
TUESDAY...MAINLY VFR.
WEDNESDAY THROUGH FRIDAY...PERIODIC CHANCE FOR SNOW SHOWERS AND
MVFR. OTHERWISE VFR.
MDB
&&
.MARINE...
307 PM CST
NO CHANGES WERE MADE TO THE ONGOING HEADLINES AS GALES ARE STILL
EXPECTED.
THE LOW IS OVER THE MID MISSISSIPPI RIVER VALLEY AND WHILE IT IS
FILLING SLOWER THAN PREVIOUSLY EXPECTED...IT IS STILL EXPECTED TO
FILL AS MOVES ACROSS SOUTHERN IL. A SECOND LOW IS MOVING INTO
NORTHERN QUEBEC AND ITS COLD FRONT WILL SINK SOUTH DOWN THE LAKE
SUNDAY AND SUNDAY NIGHT. AS THE GRADIENT TIGHTENS
TONIGHT...SOUTHWEST WINDS INCREASE TO GALES OVER THE NORTHERN HALF
TO THE LAKE. WINDS TURN WEST ACROSS THE LAKE AND INCREASE TO LOW END
GALES BY SUNDAY MORNING. WINDS DIMINISH SUNDAY AFTERNOON...AND MAY
COME DOWN BEFORE THE END OF THE GALE WARNING.
WINDS THEN TURN NORTH BEHIND THE FRONT SUNDAY NIGHT AND REMAIN AT 20
TO 25 KT...POSSIBLY UP TO 30 KT AT TIMES...THROUGH MONDAY NIGHT.
HIGH PRESSURE MOVES OVER THE UPPER PLAINS MONDAY NIGHT AND SLIDES
SOUTHEAST REACHING THE SE US WEDNESDAY. WINDS DIMINISH TUESDAY AND
BECOME WEST. GUIDANCE DIFFERS IN REGARDS TO THE PATTERN MID NEXT
WEEK. THE ECMWF FEATURES A DEEP LOW OVER THE LAKE WHILE THE GFS HAS
A WEAK SURFACE TROUGH. BOTH DO FEATURE A HIGH MOVING OVER THE
PLAINS. SO HAVE WINDS BECOMING NORTHWEST AND/OR NORTH WEDNESDAY
NIGHT...AND IF THE LOW IS DEEPER...WINDS COULD BE STRONGER. AS THE
HIGH PASSES TO THE SOUTH LATE NEXT WEEK...WINDS WEAKEN AND BECOME
WEST.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ023-ILZ033-ILZ039 UNTIL 9 PM
SATURDAY.
IN...WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 9 PM
SATURDAY.
LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 AM SUNDAY TO 3 PM
SUNDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868...MIDNIGHT SUNDAY TO 3 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...3 AM SUNDAY TO 10
PM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745...9 AM SUNDAY TO 4 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...3 AM SUNDAY TO 9
AM SUNDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
618 PM CST SAT JAN 18 2014
.DISCUSSION...
228 PM CST
REST OF TODAY...
SURFACE LOW IS DIVING SOUTHEAST INTO WEST CENTRAL ILLINOIS THIS
AFTERNOON WITH A NARROW BAND OF MODERATE TO HEAVY SNOW STRETCHING
ACROSS NORTH CENTRAL ILLINOIS INTO NORTHWEST INDIANA. SYSTEM HAS
BEEN FAIRLY WELL BEHAVED SO FAR WITH REPORTS OF AROUND 3-4 INCHES IN
THE AREAS THAT HAVE SEEN THE MOST SNOW THUS FAR. DECENT PACKING OF
THE PRESSURE IS NOTED ON THE 280-285K THETA SURFACES...WITH THE BEST
ASCENT PROGGED TO GRADUALLY SHIFT SOUTHEAST OUT OF THE CWA BY MID
EVENING. RAP H7 F-GEN SEEMS TO INITIALIZE NICELY...LINING UP WELL
WITH RADAR AND STRETCHING FROM THE SOUTH SUBURBS INTO NORTHWEST
INDIANA...AND PIVOTING TO THE EAST OUT OF THE AREA. THE RAP DOES
PICK UP ON F-GEN RESTRENGTHENING THIS EVENING OVER A SIMILAR AREA
AND GRADUALLY SINKING SOUTH ACROSS THE REMAINDER OF THE CWA BY LATE
THIS EVENING. WITH THIS IN MIND...DID SLOW DOWN THE TIMING OF SNOW
ENDING THIS EVENING IN THE GRIDS BY A FEW HOURS.
TONIGHT THROUGH SUNDAY...
THE POTENT UPPER WAVE THAT IMPACTED THE AREA TODAY WILL DEPART
ACROSS THE OHIO VALLEY THIS EVENING AND TONIGHT WITH MID/UPPER
RIDGING BUILDING INTO THE UPPER MIDWEST AND WESTERN LAKES REGION.
STRONG SFC PRESSURE RISES WILL MOVE IN BEHIND THE QUICKLY DEPARTING
LOW AND IS EXPECTED TO LEAD TO BREEZY CONDITIONS THIS
EVENING...MAINLY SOUTH OF I-80. FAIRLY STRONG HEIGHT RISES ALOFT
WILL ALSO OVERSPREAD THE AREA...PERSISTING THROUGH THE DAY SUNDAY
AND SHOULD PROVIDE A BRIEF RESPITE IN THE PRECIPITATION. ONCE THE
SURFACE/LOW LEVEL RIDGE AXIS PASSES OVER THE AREA LATE
TONIGHT...WINDS WILL BACK TO THE SOUTHWEST AND WARMER AIR WILL
ADVECT OVERHEAD...WITH H85 TEMPS RISING TO AROUND 2-3C BY SUNDAY
MORNING. SURFACE TEMPERATURES SHOULD REBOUND TO NEAR THE FREEZING
MARK DURING THE DAY SUNDAY...OTHERWISE SHOULD BE A QUIET WEATHER DAY
TOMORROW.
MONDAY THROUGH TUESDAY ...
MAIN CONCERN AS WE HEAD INTO NEXT WEEK WILL BE THE RETURN OF COLD
ARCTIC AIR. WEST COAST RIDGE IS PROGGED TO AMPLIFY OVER THE
WEEKEND...STRETCHING NORTH ACROSS ALASKA WHICH IN COMBINATION WITH A
DEEPENING LOW OVER ONTARIO WILL DISLODGE AIR FROM THE ARCTIC SOUTH
INTO THE NORTHERN LAKES REGION SUNDAY INTO MONDAY. THE LEADING EDGE
OF THIS COLD AIRMASS WILL SINK SOUTH BEHIND A COLD FRONT THAT WILL
PASS SOUTH OVER THE AREA EARLY MONDAY. TEMPERATURES BEHIND THE FRONT
ARE EXPECTED TO BE FALLING THROUGH THE DAY MONDAY. H85 TEMPS ARE
EXPECTED TO FALL TO AROUND -20C AND GENERALLY PERSIST THROUGH THE
END OF THE WEEK. STEEP LOW LEVEL LAPSE RATES DEVELOP BEHIND THE
FRONT AND APPEARS FAVORABLE FOR COLD AIR CU WITH SOME FLURRIES
DEVELOPING IF NOT A FEW SNOW SHOWERS. ACROSS NORTHWEST
INDIANA...WILL ALSO HAVE TO KEEP AN EYE ON THE LAKE EFFECT MACHINE
WHICH WILL BE RAMPING UP...AND APPEARS VERY FAVORABLE TO SEE SOME
SIGNIFICANT SNOW ACCUMULATIONS IN OR NEAR OUR EASTERN COUNTIES.
OVER LAND...LAPSE RATES WEAKEN MONDAY NIGHT AND APPEARS THAT WE
SHOULD BE WELL ENTRENCHED IN THE COLD/DRY AIR TUESDAY LEADING TO
MOST AREAS STAYING DRY OUTSIDE OF THE LAKE EFFECT.
WEDNESDAY THROUGH FRIDAY...
REGION REMAINS UNDER AN ACTIVE NORTHWEST FLOW PATTERN THROUGH THE
END OF NEXT WEEK RESULTING IN SEVERAL PERIODS OF SNOWFALL AS WAVES
ROTATE ACROSS THE AREA. MODELS HAVE BEEN TRENDING TOWARDS A MORE
ROBUST UPPER WAVE DROPPING ACROSS THE REGION MIDWEEK. SHOULD THIS
PAN OUT...MIGHT SEE A BRIEF/MODEST WARMUP AHEAD OF THE SYSTEM...BUT
THEN EVEN COLDER AIR SPILLING BEHIND. BOTH GEM AND ECMWF INDICATE
TEMPS FALLING TO AROUND -24C AT H85 WEDNESDAY. WHILE ITS PROBABLY A
BIT FAR OUT TO START TALKING LOW TRACK AND POTENTIAL SNOW...FOR NOW
AT LEAST MODELS INDICATE THE LOW WILL STAY NORTH OF THE CWA.
TEMPERATURES SHOULD REMAIN WELL BELOW NORMAL WEDNESDAY AND
THURSDAY...AND ARE EXPECTED TO BEGIN TO MODERATE SOME BY FRIDAY.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* LIGHT SNOW TAPERING OFF EARLY THIS EVENING...VARIABLE 2-5SM VSBY
POSSIBLE AS DIMINISHING SNOW SHOWERS PUSH ACROSS.
* VARIABLE MVFR/VFR CIGS EARLY THIS EVENING WITH SCATTERING LATE
THIS EVENING.
* EAST-NORTHEAST WINDS TURNING NORTH-NORTHWEST MID EVENING.
* GUSTY SOUTHWEST WINDS EXPECTED SUNDAY MORNING INTO EARLY SUNDAY
AFTERNOON...25-30 KT POSSIBLE.
MDB
//DISCUSSION...UPDATED 00Z...
LOW PRESSURE CENTERED NEAR KBMI/KDEC AREA CONTINUES TO MOVE
EASTWARD THIS EVENING WITH AN UPPER TROUGH AXIS SWINGING ACROSS
THE AREA AS WELL. ASSOCIATED AREA OF SNOW CONTINUES TO TRANSITION
TO THE SOUTH AND EAST AS WELL WITH THE TERMINALS SEEING IMPROVED
CONDITIONS OVERALL...THOUGH GYY WILL LIKELY SEE STEADIER SNOW A
BIT LONGER. WITH RADAR SHOWING A DECREASING TREND IN SNOW OVER AND
TO THE NORTH OF THE CHICAGO TERMINALS EXPECT THAT THERE WILL BE
VARIABLE VSBY BETWEEN 2 AND 5SM WITH PERIODS OF SNOW OVER THE
NEXT FEW HOURS BEFORE SNOW ENDS. CIGS HAVE BECOME VARIABLE AS WELL
WITH MUCH IMPROVED BASES OVER SEVERAL HOURS AGO. EXPECT THAT A MIX
OF MVFR/VFR WILL CONTINUE WITH THE SNOW IN THE AREA BUT THEN
BECOME MAINLY VFR TOWARD MID EVENING AS SNOW DEPARTS. SATELLITE
IMAGERY SHOWS SIGNIFICANT CLEARING UPSTREAM OF THE AREA SO HAVE
IMPROVED AND SCATTERED CIGS INTO THE OVERNIGHT. WITH THE LOW
PASSING TO THE SOUTH WINDS WILL SHIFT FROM NORTHEAST TO NORTH-
NORTHWEST OVER THE NEXT FEW HOURS...WITH SPEEDS UNDER 10 KT AS THE
PRESSURE GRADIENT NORTH OF THE LOW WEAKENS. A FURTHER SHIFT TO
WEST AND SOUTHWEST WILL OCCUR OVERNIGHT.
EXPECT VFR SUNDAY BUT SOUTHWEST WINDS LOOK TO RAMP UP DURING THE
MORNING. GUSTS MAY PUSH 30 KT FROM LATE MORNING THROUGH EARLY
AFTERNOON BEFORE SPEEDS EASE LATER IN THE DAY. WINDS JUST ABOVE
THE SURFACE WILL BE INCREASING AS WELL WITH 55-60 KT POSSIBLE NEAR
2000 FT AGL. THIS MAY RESULT IN SOME LOW LEVEL WIND SHEAR BUT WILL
LEAVE MENTION OUT OF THE TAF FOR NOW. IT COULD BE THAT HIGHER
SURFACE GUSTS RESULT WITH ENOUGH MIXING SO WILL NEED TO MONITOR
FOR ANY UPWARD ADJUSTMENTS.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH CONFIDENCE IN LIGHT SNOW TAPERING OFF THIS EVENING. HIGH
CONFIDENCE THAT THERE WILL BE VARIABLE VSBY AT TIMES...WITH
MEDIUM CONFIDENCE IN ENDING TIME OF SNOW.
* HIGH CONFIDENCE IN VARIABLE MVFR/VFR CIGS BECOMING
VFR/SCATTERING WITH TIME.
* HIGH CONFIDENCE IN WIND TRENDS THROUGH THE EVENING AND TIMING OF
SHIFT TO NORTH-NORTHWEST.
* MEDIUM-HIGH CONFIDENCE IN MAGNITUDE OF WINDS SUNDAY.
MDB
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...CHANCE SNOW SHOWERS...MVFR POSSIBLE.
TUESDAY...MAINLY VFR.
WEDNESDAY THROUGH FRIDAY...PERIODIC CHANCE FOR SNOW SHOWERS AND
MVFR. OTHERWISE VFR.
MDB
&&
.MARINE...
307 PM CST
NO CHANGES WERE MADE TO THE ONGOING HEADLINES AS GALES ARE STILL
EXPECTED.
THE LOW IS OVER THE MID MISSISSIPPI RIVER VALLEY AND WHILE IT IS
FILLING SLOWER THAN PREVIOUSLY EXPECTED...IT IS STILL EXPECTED TO
FILL AS MOVES ACROSS SOUTHERN IL. A SECOND LOW IS MOVING INTO
NORTHERN QUEBEC AND ITS COLD FRONT WILL SINK SOUTH DOWN THE LAKE
SUNDAY AND SUNDAY NIGHT. AS THE GRADIENT TIGHTENS
TONIGHT...SOUTHWEST WINDS INCREASE TO GALES OVER THE NORTHERN HALF
TO THE LAKE. WINDS TURN WEST ACROSS THE LAKE AND INCREASE TO LOW END
GALES BY SUNDAY MORNING. WINDS DIMINISH SUNDAY AFTERNOON...AND MAY
COME DOWN BEFORE THE END OF THE GALE WARNING.
WINDS THEN TURN NORTH BEHIND THE FRONT SUNDAY NIGHT AND REMAIN AT 20
TO 25 KT...POSSIBLY UP TO 30 KT AT TIMES...THROUGH MONDAY NIGHT.
HIGH PRESSURE MOVES OVER THE UPPER PLAINS MONDAY NIGHT AND SLIDES
SOUTHEAST REACHING THE SE US WEDNESDAY. WINDS DIMINISH TUESDAY AND
BECOME WEST. GUIDANCE DIFFERS IN REGARDS TO THE PATTERN MID NEXT
WEEK. THE ECMWF FEATURES A DEEP LOW OVER THE LAKE WHILE THE GFS HAS
A WEAK SURFACE TROUGH. BOTH DO FEATURE A HIGH MOVING OVER THE
PLAINS. SO HAVE WINDS BECOMING NORTHWEST AND/OR NORTH WEDNESDAY
NIGHT...AND IF THE LOW IS DEEPER...WINDS COULD BE STRONGER. AS THE
HIGH PASSES TO THE SOUTH LATE NEXT WEEK...WINDS WEAKEN AND BECOME
WEST.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ008-ILZ010-ILZ011-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ032 UNTIL 6 PM SATURDAY.
WINTER WEATHER ADVISORY...ILZ023-ILZ033-ILZ039 UNTIL 9 PM
SATURDAY.
IN...WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 9 PM
SATURDAY.
LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 AM SUNDAY TO 3 PM
SUNDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868...MIDNIGHT SUNDAY TO 3 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...3 AM SUNDAY TO 10
PM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745...9 AM SUNDAY TO 4 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...3 AM SUNDAY TO 9
AM SUNDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
725 PM EST SAT JAN 18 2014
.SYNOPSIS...
ISSUED AT 712 PM EST SAT JAN 18 2014
MODERATE TO BRIEFLY HEAVY SNOW HAS SPREAD ACROSS THE FORECAST
AREA. ACCUMULATING SNOWFALL WILL CONTINUE THROUGH MIDNIGHT
TONIGHT. TOTAL SNOWFALL ACCUMULATION WILL BE 3 TO 5 INCHES IN
SOUTHWESTERN AREAS...ALONG AND SOUTH OF ROUTE 24...WITH GENERALLY
1 TO 2 INCHES NORTHH. LOW TEMPERATURES TONIGHT WILL FALL INTO THE
LOWER TO MID TEENS BEFORE TEMPERATURES WARM INTO THE MID 20S
SUNDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 320 PM EST SAT JAN 18 2014
TWO CHALLENGES IN THE SHORT TERM: DURATION/INTENSITY/AMOUNT OF SNOW
AND MIN TEMPERATURE TONIGHT/SUNDAY MORNING.
THE CLIPPER SYSTEM IS WELL FORECAST BY THE MODELS THIS AFTERNOON AND
MORNING INITIALIZATIONS WERE NEARLY SPOT ON. LATEST SATELLITE/RADAR
DATA SHOW THE DEEPENING WAVE AND ASSOCIATED WARM SECTOR ASSENT ON
THE EAST AND NORTHEAST AREA IS HOLDING TOGETHER WELL. EXPECT TO SEE
THE LEADING EDGE OF THE SNOW ACROSS THE SOUTHWEST PORTION OF THE CWA
BETWEEN 2-4 PM EST AND THIS WILL SHIFT NORTH AND EAST DURING THE
EVENING. AM CONCERNED THAT THE DRIER AIR IS STARTING TO WRAP AROUND
THE LOW AND THIS SHOULD BE ENOUGH TO CREATE A VERY NARROW
PRECIPITATION BAND. AS MODELS ARE STARTING TO SHOW...THIS WILL BE A
RAPIDLY MOVING SYSTEM AND WHILE THERE ARE HINTS OF FAVORABLE
FRONTOGENETIC FORCING...THE RAPID TRANSITORY NATURE WILL RESULT
GENERAL AREAS OF SNOWFALL WITH EMBEDDED BANDS OF ENHANCED SNOWFALL.
BY MIDNIGHT...THE SYSTEM WILL HAVE BECOME MORE OF AN OPEN WAVE AND
THIS WILL BRING THE SNOWFALL TO A QUICK END FROM WEST TO EAST. MODEL
SOUNDINGS SUGGEST THAT CLOUDS/STRATUS WILL PERSIST OVER MUCH OF THE
AREA...BUT THIS LEADS TO THE SECOND CHALLENGE FOR THE PERIOD. AS THE
TROF OPENS UP AND THE FLOW TURNS MORE WESTERLY...THE POTENTIAL FOR
CLEARING SKIES IS BECOMING MORE LIKELY. AS A RESULT HAVE TRIMMED THE
OVERNIGHT LOWS A FEW DEGREES. THE RUC AND LOCAL WRF ARE BY FAR THE
COOLEST OF THE MODELS AT THIS TIME AND GIVEN THE CLEARING NOTED IN
THE WAKE OF THE SYSTEM...FEEL COMPELLED TO LEAN TOWARD THE COOLER
SOLUTIONS. ONLY A MINOR DOWNWARD ADJUSTMENT MADE.
EXPECT TO SEE A FEW LAKE ENHANCED SNOW SHOWERS DURING THE DAY SUNDAY
WITH FAVORED AREAS NEAR THE SHORELINE AND LIGHT SNOW SHOWERS ALONG
AND NORTH OF US-30.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 320 PM EST SAT JAN 18 2014
ONCE AGAIN VERY FEW CHANGES NEEDED TO LONG TERM WITH PERSISTENT BUT
ACTIVE PATTERN. LONG WAVE TROUGH REMAINS ANCHORED OVER THE GREAT
LAKES WITH LARGE SCALE RIDGE OVER WEST COAST. DEEP NORTHERLY FLOW
WILL KEEP THE POLAR EXPRESS OF SHORT WAVES ON TRACK WITH SEVERAL
WAVES OVER THE NEXT WEEK. LAKE EFFECT WILL BE ONGOING FOR ABOUT THE
ENTIRE PERIOD BUT BACKING AND VEERING WINDS MAKE BAND ORIENTATION
AND PLACEMENT DIFFICULT AT BEST AT THIS TIME RANGE.
NEXT ARCTIC BOUNDARY STILL SET TO PLUNGE SOUTH ACROSS THE AREA ON
MONDAY. EARLY MORNING HIGHS EXPECTED WITH WINDS BECOMING NORTH
THROUGH THE DAY AND COLD AIR ADVECTION DEEPENING. WILL CONTINUE WITH
LOW CHANCE POPS FOR FLURRIES/LIGHT SNOW SHOWERS AS COLD AIR DEEPENS.
LAKE EFFECT TO LIKELY BE SLOW AND LIGHT AT FIRST BUT AS SECONDARY
FRONT AND COLDER AIR MOVE IN LATER MONDAY AND ESPECIALLY MONDAY
NIGHT INTO TUESDAY...SHOULD SEE THE LAKE EFFECT MACHINE CRANK INTO
FULL GEAR. STILL EXPECT A SIGNIFICANT SINGLE BAND SOMEWHERE BETWEEN
EXTREME SOUTHWEST BERRIEN COUNTY AND PORTER COUNTY IN NW INDIANA.
THIS WILL DEPEND ON STRENGTH OF CONVERGENCE. UPSTREAM CONDITIONING
EXPECTED WITH LONG FETCH AND EXTREME DELTA TS SO SIGNIFICANT
ACCUMULATIONS LIKELY...JUST A QUESTION OF EXACTLY WHERE. STILL NEED
A FEW MORE MODEL ITERATIONS BEFORE HIGHER RESOLUTION GUIDANCE BEGINS
TO PICK UP THESE PERIODS.
REST OF THE WEEK TO SEE A CONTINUATION OF MEANDERING LAKE EFFECT
BANDS AND COLD TEMPS. AS WE HAVE BEEN DISCUSSING...HIGHS IN SINGLE
DIGITS TO TEENS WITH LOWS AROUND ZERO TO 6 BELOW RIGHT NOW. REALLY
EXPECT SOME COLDER READINGS...ESPECIALLY IF WE DECOUPLE AND ARE
CLEAR TUE NIGHT WITH HIGH PRESSURE MOVING THROUGH AND FRESH SNOWPACK.
COULD SEE LOWS BOTTOM OUT IN RURAL AREAS IN THE 10 TO 15 BELOW RANGE
AGAIN IF IDEAL RADIATIONAL CONDITIONS DEVELOP. FOR NOW STAYED ON THE
CONSERVATIVE SIDE OF COLDER BLENDS AROUND 5 BELOW.
YET ANOTHER SHORT WAVE AND REINFORCED SHOT OF COLD AIR AROUND MID
WEEK WILL KEEP CHANCES FOR SNOW SHOWERS GOING. MEDIUM RANGE MODELS
HINT AT ANOTHER POSSIBLE SINGLE BAND BEHIND THIS WAVE. LOWS THU
NIGHT HAVE POTENTIAL TO GO EVEN LOWER THAN CURRENT FCST LOWS IF HIGH
PRESSURE SLIDES IN AND WE DECOUPLE AGAIN.
SLIGHT MODERATION IN MODELS BEING SHOWN FOR DAY 7 BEFORE NEXT POLAR
EXPRESS SHORT WAVE MOVES IN EARLY IN WEEK TWO PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 724 PM EST SAT JAN 18 2014
GENERAL IMPROVEMENT AT KSBN AS SATURATED DGZ THICKNESS RAPIDLY
DIMISHES. DEEPER SATURATION/PROXIMITY TO MULTI-MESO BANDS ASSOCD
WITH WEAKER CONDITIONAL STABILITY SHOULD MAINTAIN SIG LWR VSBYS
AT KFWA THROUGH AT LEAST 03 UTC...BEFORE IMPROVING TO LOW END
MVFR CONDS. CONCERN FOR CIGS TO REMAIN IN FUEL ALT STATUS TO BYND
DAYLIGHT AS MSTR BECOMES LOCKED BENEATH LWRG SUBSIDENCE INVERSION
BYND MIDNIGHT. RAMPED LLJ/STRONG WARM AIR ADVECTION ON SUNDAY
LENDS TO SIG INCRS IN WIND FORECAST AND WHILE MECHANICAL
TURBULENCE/GUSTS MIGHT PROVE DIFFICULT SPCLY FOR VFR GA...DO NOT
EXPECT TRUE WIND SHEAR CRITERIA TO BE MET GIVEN DEGREE OF MIXING.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL 1 AM EST SUNDAY FOR INZ025>027-033-
034.
WINTER WEATHER ADVISORY UNTIL 9 PM EST /8 PM CST/ THIS EVENING
FOR INZ012-013-020-022.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR INZ015-
023-024-032.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY FROM 7 AM SUNDAY TO MIDNIGHT EST SUNDAY
NIGHT FOR LMZ043-046.
&&
$$
SYNOPSIS...ESB
SHORT TERM...LASHLEY
LONG TERM...LEWIS
AVIATION...MURPHY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
806 AM EST FRI JAN 17 2014
.SYNOPSIS...
ISSUED AT 804 AM EST FRI JAN 17 2014
AN UPPER LEVEL DISTURBANCE WILL TRACK ACROSS THE GREAT LAKES
REGION LATE THIS AFTERNOON AND EVENING BRINGING SCATTERED SNOW
SHOWERS TO THE AREA. MUCH COLDER AIR WILL MOVE IN TODAY WITH
TEMPERATURES FALLING BACK INTO THE MID TO UPPER TEENS.
ANOTHER STRONG UPPER LEVEL DISTURBANCE WILL CROSS THE REGION
SATURDAY AFTERNOON AND EVENING...BRINGING A GOOD CHANCE OF ACCUMULATING
SNOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 334 AM EST FRI JAN 17 2014
SECONDARY SW DISTURBANCE OVR NE MO EARLY THIS MORNING WILL PIVOT EWD
THROUGH BASE OF LW TROUGH EXTENDING SWD OUT OF HUDSON BAY AND INTO
CNTRL OH BY EVENING. SUSPECT -SHSN WILL BLOSSOM ONCE AGAIN
DOWNSTREAM AFT SUNRISE GENERALLY SOUTH OF THE 24 CORRIDOR FOLLOWING
DEEPER COLD POCKET ALOFT AND INTO NW OH THIS AFTN. OTRWS XPC LK
ACTIVATION WILL HAVE TO WAIT UNTIL LT THIS AFTN TIMED W/PASSAGE OF
ADDNL MID LVL TROUGH BACK NW ACRS CNTRL WI THIS MORNING AS LL FLW
VEERS NWRLY. HWVR W/MOST INTENSE LL THERMAL TROUGHING PASSING WELL
SOUTH THROUGH SRN FLANK OF MO DISTURBANCE...DOUBT IT WILL
AMT TO MUCH OVERNIGHT. HIGHS EARLY W/STEADY TO SLOWLY FALLING
TEMPS THROUGH THIS AFTN AS CAA WEDGE DEEPENS ACRS THE AREA.
&&
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 334 AM EST FRI JAN 17 2014
AMPLIFIED POSITIVE PNA PATTERN WILL PERSIST THROUGH THE PERIOD WITH
BROAD EASTERN CONUS LONGWAVE TROUGH LOCKED IN DOWNSTREAM OF AN
IMPRESSIVE WEST COAST/ALASKA RIDGE. THIS WILL KEEP THE LOCAL AREA IN
AN ACTIVE/COLD NORTHWEST FLOW REGIME.
PRIMARY UPPER PV ANOMALY OF INTEREST...NEARING THE ALBERTA/NORTHWEST
TERRITORIES AS OF THIS WRITING...IS STILL MODELED TO DROP QUICKLY
SOUTHEAST ON THE NOSE OF A 130-140 UPPER JET AND IMPACT THE IWX CWA
SATURDAY AFTERNOON INTO SATURDAY EVENING. AS EXPECTED MODELS
CONTINUE TO BOUNCE AROUND SOME ON TRACK/INTENSITY/TIMING...WITH THE
OVERALL TREND IN 00Z GUIDANCE TO SHIFT A BIT SOUTH/SOUTHWEST AND
WEAKER WITH WAVE. HARD TO TAKE THIS TREND AND ONE MODEL CYCLE TOO
SERIOUS WITH WAVE IN FAR NORTHWEST CANADA AT 00Z. AS A RESULT MADE
ONLY MINOR TWEAKS TO THE GRIDS FAVORING A GFS/ECMWF SFC LOW TRACK
SOUTHEAST THROUGH CENTRAL ILLINOIS/INDIANA. SHOULD BE A NARROW BAND
OF ACCUMULATION SNOW (2-5") JUST NORTH-NORTHEAST OF THIS LOW TRACK
WITH CONFIDENCE ON WHERE EXACTLY THIS SWATH OF HEAVIER SNOW FALLS
SOMEWHAT LOW GIVEN LINGERING MODEL SPREAD. ATTM IT LOOKS LIKE BEST
CHANCES FOR A PLOWABLE SNOW ARE ACROSS WESTERN/SOUTHERN PORTIONS OF
THE FA. LOWER PROBABILITY EXISTS FOR SOME HEAVIER RATES/TOTALS NEAR
6 INCHES AS SOME GUIDANCE STILL SHOWS A CLOSED MID LVL CIRCULATION,
STEEP MID LVL LAPSE RATES, AND GOOD SNOW GROWTH WITH 850-700 MB
TEMPS AVERAGING IN FAVORABLE -10C TO -20C RANGE...WITH MOISTURE AND
QUICK MOVEMENT LIMITING FACTORS.
BREEZY, DRY, AND SLIGHTLY WARMER FOR THE SECOND HALF OF THE WEEKEND
AS LOW LEVEL FLOW BRIEFLY BACKS SOUTHWEST IN ADVANCE OF AN ARCTIC
FRONT. NOT EXPECTING MUCH IN THE WAY OF SNOW WITH THIS ARTIC FRONT
THAT WILL USHER IN FRIGID TEMPERATURES (WELL BELOW NORMAL) FOR
MUCH OF NEXT WEEK. LAKE-700 MB TEMP DIFFERENTIALS IN THE MID 20S TO
LOW 30S AND POTENTIAL FOR A PROLONGED PERIOD OF NORTH-NORTHWEST
TRAJECTORIES BRINGS ABOUT CONCERNS FOR A SIGNIFICANT LAKE EFFECT
SNOW EVENT IN THE FAR NORTHWEST...MAINLY IN THE LATE MON-TUE
PERIODS. OTHERWISE...SEVERAL CHANCES FOR SYNOPTIC SNOWS AND LAKE
ENHANCEMENT WED-FRI AS SEVERAL MORE CLIPPER SYSTEMS DROP THROUGH.
&&
.AVIATION/UPDATE...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 622 AM EST FRI JAN 17 2014
COMPLICATED PATTN THIS MORNING OVERHEAD W/MULTIPLE DISTURBANCES
EMBEDDED WITHIN LARGER SCALE LW TROUGH EXTENDING SWD FM HUDSON BAY.
MOST VIGOROUS FTR OF NOTE IS CLOSED LOW MIGRATING EWD THROUGH CNTRL
IL W/BLOSSOMING AREA OF CONV SNOW SHOWERS DVLPG IN EARNEST ACRS SRN
IN/WRN KY. THIS LEADS TO SOME CONCERN AS SEEN IN RECENT RUC WWD
TRENDS TAKING SNOW INTO ERN NW OHIO COUNTIES FM LTR MORNING INTO MID
AFTN. HAVE BUMPED EXTREME ERN COUNTIES TO ACCOUNT FOR THIS BUT VAPOR
IMAGERY SUGGESTS SOME FURTHER WWD EXPANSION PSBL.
TERMINALS A BIT MORE STRAIGHT FWD EARLY ON BUT TURN COMPLICATED BY
LT AFTN INADV OF TERTIARY DISTURBANCE WRAPPING UP NRN WI ATTM. ALL
GUIDANCE PROGS THIS FTR TO WKN YET BELIEVE A PD OF DIURNALLY
ENHANCED -SHSN MAY OCCUR THIS AFTN ESP NW HALF. OTRWS WIDESPREAD
MVFR CIGS FILLING UP WWD/SWWD WITHIN CAA WEDGE AND XPC THIS WILL
OVERSPREAD ACRS THE TERMINALS THROUGH SUNRISE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR LMZ043-046.
&&
$$
SYNOPSIS...KG
SHORT TERM...T
LONG TERM...STEINWEDEL
AVIATION...T
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
624 AM EST FRI JAN 17 2014
.SYNOPSIS...
ISSUED AT 1248 AM EST FRI JAN 17 2014
ANOTHER IS A SERIES OF UPPER LEVEL DISTURBANCES WILL TRACK ACROSS
THE GREAT LAKES REGION LATE THIS AFTERNOON AND EVENING BRINGING
SCATTERED SNOW SHOWERS. MUCH COLDER AIR WILL OVERSPREAD THE TODAY
WITH MORNING HIGH TEMPERATURES FALLING BACK INTO THE MID TO UPPER
TEENS.
ANOTHER STRONG UPPER LEVEL DISTURBANCE WILL CROSS THE REGION
SATURDAY AFTERNOON AND EVENING...BRINGING A GOOD CHANCE OF ACCUMULATING
SNOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 334 AM EST FRI JAN 17 2014
SECONDARY SW DISTURBANCE OVR NE MO EARLY THIS MORNING WILL PIVOT EWD
THROUGH BASE OF LW TROUGH EXTENDING SWD OUT OF HUDSON BAY AND INTO
CNTRL OH BY EVENING. SUSPECT -SHSN WILL BLOSSOM ONCE AGAIN
DOWNSTREAM AFT SUNRISE GENERALLY SOUTH OF THE 24 CORRIDOR FOLLOWING
DEEPER COLD POCKET ALOFT AND INTO NW OH THIS AFTN. OTRWS XPC LK
ACTIVATION WILL HAVE TO WAIT UNTIL LT THIS AFTN TIMED W/PASSAGE OF
ADDNL MID LVL TROUGH BACK NW ACRS CNTRL WI THIS MORNING AS LL FLW
VEERS NWRLY. HWVR W/MOST INTENSE LL THERMAL TROUGHING PASSING WELL
SOUTH THROUGH SRN FLANK OF MO DISTURBANCE...DOUBT IT WILL
AMT TO MUCH OVERNIGHT. HIGHS EARLY W/STEADY TO SLOWLY FALLING
TEMPS THROUGH THIS AFTN AS CAA WEDGE DEEPENS ACRS THE AREA.
&&
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 334 AM EST FRI JAN 17 2014
AMPLIFIED POSITIVE PNA PATTERN WILL PERSIST THROUGH THE PERIOD WITH
BROAD EASTERN CONUS LONGWAVE TROUGH LOCKED IN DOWNSTREAM OF AN
IMPRESSIVE WEST COAST/ALASKA RIDGE. THIS WILL KEEP THE LOCAL AREA IN
AN ACTIVE/COLD NORTHWEST FLOW REGIME.
PRIMARY UPPER PV ANOMALY OF INTEREST...NEARING THE ALBERTA/NORTHWEST
TERRITORIES AS OF THIS WRITING...IS STILL MODELED TO DROP QUICKLY
SOUTHEAST ON THE NOSE OF A 130-140 UPPER JET AND IMPACT THE IWX CWA
SATURDAY AFTERNOON INTO SATURDAY EVENING. AS EXPECTED MODELS
CONTINUE TO BOUNCE AROUND SOME ON TRACK/INTENSITY/TIMING...WITH THE
OVERALL TREND IN 00Z GUIDANCE TO SHIFT A BIT SOUTH/SOUTHWEST AND
WEAKER WITH WAVE. HARD TO TAKE THIS TREND AND ONE MODEL CYCLE TOO
SERIOUS WITH WAVE IN FAR NORTHWEST CANADA AT 00Z. AS A RESULT MADE
ONLY MINOR TWEAKS TO THE GRIDS FAVORING A GFS/ECMWF SFC LOW TRACK
SOUTHEAST THROUGH CENTRAL ILLINOIS/INDIANA. SHOULD BE A NARROW BAND
OF ACCUMULATION SNOW (2-5") JUST NORTH-NORTHEAST OF THIS LOW TRACK
WITH CONFIDENCE ON WHERE EXACTLY THIS SWATH OF HEAVIER SNOW FALLS
SOMEWHAT LOW GIVEN LINGERING MODEL SPREAD. ATTM IT LOOKS LIKE BEST
CHANCES FOR A PLOWABLE SNOW ARE ACROSS WESTERN/SOUTHERN PORTIONS OF
THE FA. LOWER PROBABILITY EXISTS FOR SOME HEAVIER RATES/TOTALS NEAR
6 INCHES AS SOME GUIDANCE STILL SHOWS A CLOSED MID LVL CIRCULATION,
STEEP MID LVL LAPSE RATES, AND GOOD SNOW GROWTH WITH 850-700 MB
TEMPS AVERAGING IN FAVORABLE -10C TO -20C RANGE...WITH MOISTURE AND
QUICK MOVEMENT LIMITING FACTORS.
BREEZY, DRY, AND SLIGHTLY WARMER FOR THE SECOND HALF OF THE WEEKEND
AS LOW LEVEL FLOW BRIEFLY BACKS SOUTHWEST IN ADVANCE OF AN ARCTIC
FRONT. NOT EXPECTING MUCH IN THE WAY OF SNOW WITH THIS ARTIC FRONT
THAT WILL USHER IN FRIGID TEMPERATURES (WELL BELOW NORMAL) FOR
MUCH OF NEXT WEEK. LAKE-700 MB TEMP DIFFERENTIALS IN THE MID 20S TO
LOW 30S AND POTENTIAL FOR A PROLONGED PERIOD OF NORTH-NORTHWEST
TRAJECTORIES BRINGS ABOUT CONCERNS FOR A SIGNIFICANT LAKE EFFECT
SNOW EVENT IN THE FAR NORTHWEST...MAINLY IN THE LATE MON-TUE
PERIODS. OTHERWISE...SEVERAL CHANCES FOR SYNOPTIC SNOWS AND LAKE
ENHANCEMENT WED-FRI AS SEVERAL MORE CLIPPER SYSTEMS DROP THROUGH.
&&
.AVIATION/UPDATE...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 622 AM EST FRI JAN 17 2014
COMPLICATED PATTN THIS MORNING OVERHEAD W/MULTIPLE DISTURBANCES
EMBEDDED WITHIN LARGER SCALE LW TROUGH EXTENDING SWD FM HUDSON BAY.
MOST VIGOROUS FTR OF NOTE IS CLOSED LOW MIGRATING EWD THROUGH CNTRL
IL W/BLOSSOMING AREA OF CONV SNOW SHOWERS DVLPG IN EARNEST ACRS SRN
IN/WRN KY. THIS LEADS TO SOME CONCERN AS SEEN IN RECENT RUC WWD
TRENDS TAKING SNOW INTO ERN NW OHIO COUNTIES FM LTR MORNING INTO MID
AFTN. HAVE BUMPED EXTREME ERN COUNTIES TO ACCOUNT FOR THIS BUT VAPOR
IMAGERY SUGGESTS SOME FURTHER WWD EXPANSION PSBL.
TERMINALS A BIT MORE STRAIGHT FWD EARLY ON BUT TURN COMPLICATED BY
LT AFTN INADV OF TERTIARY DISTURBANCE WRAPPING UP NRN WI ATTM. ALL
GUIDANCE PROGS THIS FTR TO WKN YET BELIEVE A PD OF DIURNALLY
ENHANCED -SHSN MAY OCCUR THIS AFTN ESP NW HALF. OTRWS WIDESPREAD
MVFR CIGS FILLING UP WWD/SWWD WITHIN CAA WEDGE AND XPC THIS WILL
OVERSPREAD ACRS THE TERMINALS THROUGH SUNRISE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR LMZ043-046.
&&
$$
SYNOPSIS...MARSILI
SHORT TERM...T
LONG TERM...STEINWEDEL
AVIATION...T
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
148 PM EST FRI JAN 17 2014
.UPDATE...
ISSUED AT 135 PM EST FRI JAN 17 2014
BANDS OF SNOW SHOWERS ARE STILL ROTATING ACROSS THE REGION AS AN
UPPER LEVEL TROUGH AND SFC COLD FRONT CONTINUE TO WORK ACROSS THE
AREA. TEMPS IN THE FAR EAST ROSE TO NEAR 40...IF NOT ABOVE AHEAD OF
THIS BOUNDARY...BUT INCREASING CLOUDS HAVE LED TO THOSE AREAS COOLING
OFF AND THIS SHOULD OCCUR MORE RAPIDLY LATER IN THE AFTERNOON.
TEMPS HAVE FALLEN INTO THE LOW TO MID 20S OVER MUCH OF CENTRAL KY AND
TEMPS SHOULD BE INTO THE 20S IN MOST LOCATIONS BY EVENING. WITH THE
LOW LEVEL FLOW GRADUALLY BECOMING MORE WESTERLY TO NORTHWESTERLY...
THE MODELS INDICATE THAT THE BANDS OF SNOW SHOWERS SHOULD CONTINUE OFF
AND ON ACROSS THE AREA INTO THE EVENING. ATTM...THE ADVISORY AREAS
REMAIN VALID AS THE SNOW SHOWERS WORK ACROSS THE AREA AND
TEMPERATURES WILL BE DROPPING. SOME SLUSHY OR SNOW COVERED ROADS
SHOULD OCCUR IN SEVERAL LOCATIONS DURING THE EVENING COMMUTE...
ESPECIALLY IN THE SOUTHEAST TWO THIRDS OF THE CWA.
OTHER THAN SOME UPDATES TO HOURLY OBSERVATION TRENDS...NO SIGNIFICANT
CHANGES WERE MADE.
UPDATE ISSUED AT 1039 AM EST FRI JAN 17 2014
SNOW SHOWERS AND SOME ISOLATED SNOW SQUALLS ARE MOVING EAST SLIGHTLY
FASTER THAN THE PREVIOUS FORECAST. WE HAVE OPTED TO GO AHEAD AND
START THE WINTER WEATHER ADVISORY ACROSS THE SOUTHEASTERN PART OF THE
AREA A BIT QUICKER AS A RESULT. SNOW ACCUMULATIONS STILL LOOK GOOD
WITH AROUND AN INCH OR SO ON AVERAGE IN MOST LOCATIONS THROUGH THIS
EVENING. LOCALLY HIGHER AMOUNTS ARE ANTICIPATED GENERALLY ABOVE 2000
FEET NEARER TO VA AND IN ANY MORE PERSISTENT BANDS OF SNOW. ALTHOUGH
THERE WAS SOME THUNDERSNOW IN THE BAND OF SNOW SHOWERS NOW ROTATING
INTO VA AND WV...THE NEXT BANDS OF SNOW SHOWERS ARE NOT AS DEEP IN
THE ATMOSPHERE... AND LIGHTNING APPEARS LESS LIKELY BUT THEY SHOULD
BE MORE WIDESPREAD. HOURLY TEMPS AND DEWPOINTS HAVE ALSO BEEN
FRESHENED UP BASED ON THE LATEST TRENDS.
UPDATE ISSUED AT 620 AM EST FRI JAN 17 2014
DID A QUICK UPDATE TO TAKE THE FIRST ROUND OF SNOW OUT OF THE GRIDS
AND FIRM UP THE TIMING OF THE NEXT BATCH. ALSO FINE TUNED THE SKY AND
NEAR TERM TEMPS/DEWPOINTS. THESE HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 350 AM EST FRI JAN 17 2014
07Z SFC ANALYSIS SHOWS THE LATEST CLIPPER SYSTEM MOVING THROUGH THE
GREAT LAKES. THIS IS PUSHING AN ARCTIC BOUNDARY INTO THE WESTERN
PORTIONS OF THE OHIO VALLEY. AHEAD OF THIS...A DISTURBANCE AT MID
LEVELS HAS SENT A NEW BATCH OF SNOW SHOWERS THROUGH EAST KENTUCKY
WHITENING SOME PLACES UP TO AN INCH AS IT PASSES. AT THE WEATHER
OFFICE WE PICKED UP A QUICK 7 TENTHS OF AN INCH AS ONE OF THOSE BANDS
MOVED THROUGH. TEMPERATURES AROUND FREEZING AND ROAD TEMPERATURES IN
MOST PLACES ABOVE FREEZING WILL LIMIT THE IMPACT FROM THESE SNOW
SHOWERS. OVER THE SOUTHERN PARTS OF THE CUMBERLAND VALLEY THE
DEWPOINTS HAVE COME UP INTO THE LOW TO MID 30S AND THIS IS LEADING TO
MORE OF A RAIN EVENT WITH THIS ROUND RATHER THAN SNOW. IT IS A FINE
LINE...THOUGH...SO WILL CONTINUE THE SPS THAT IS OUT THROUGH 16Z FOR
THAT AREA. DESPITE A FEW HEAVIER BANDS...THE BULK OF THE AREA WILL
SEE AROUND A HALF AN INCH OF ACCUMULATION OR LESS THOUGH DAWN.
SLIGHTLY BETTER TOTALS CAN BE EXPECTED ALONG AND IN THE IMMEDIATE
WAKE OF THE ARCTIC BOUNDARY LATER TODAY.
THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT AS THEY ALL SHOW A
POTENT SHORTWAVE CROSSING THROUGH THE SOUTHERN OHIO VALLEY TODAY
WITHIN THE HEART OF A DEEP TROUGH. THIS WAVE WILL BRING SOME STEEP
LAPSE RATES TO THE LOWER PART OF THE ATMOSPHERE LATER THIS MORNING
AND THROUGH THE AFTERNOON HELPING TO ENHANCE THE LIFT AND SHOWERY
NATURE OF THE SNOW. THIS FEATURE MOVES QUICKLY OFF TO THE NORTHEAST
TONIGHT AS THE LARGER TROUGH TEMPORARILY RETREATS TO THE NORTH.
ACCORDINGLY...HEIGHTS WILL MODERATE THROUGH THE AREA INTO SATURDAY
MORNING. THIS PROCESS IS THEN QUICKLY REVERSED LATER THAT DAY AS THE
NEXT SHARP WAVE DROPS SOUTHEAST THROUGH THE MIDWEST...MAKING ITS RUN
TOWARD THE OHIO VALLEY. WITH THE GENERAL MODEL AGREEMENT AND THE
MESOSCALE NATURE OF THE SNOW BANDS AND ARCTIC BOUNDARY...HAVE LEANED
TOWARD THE HIGHER RESOLUTION HRRR AND NAM12 THROUGH THE SHORT TERM.
SENSIBLE WEATHER WILL FEATURE THE PRE-DAWN SNOW...AND FAR SOUTHERN
KY RAIN...SHOWERS EXITING THE AREA WITH A BIT OF A LULL IN ANY PCPN
ACTIVITY UNTIL AROUND MID MORNING IN THE WEST WHEN THE ARCTIC
BOUNDARY MOVES INTO THE CWA. THIS WILL BRING ANOTHER ROUND OF SNOW
SHOWERS...COLDER TEMPERATURES...AND BRISK WINDS TO THE AREA TODAY.
ALTHOUGH MOISTURE IS LIMITED WITH THIS...STILL EXPECT THE LIFT ALONG
THE FRONT AND STEEP LAPSE RATES BEHIND IT TO SUPPORT SNOW SHOWERS
INTENSE ENOUGH TO ACCUMULATE FOR MOST LOCATIONS...GENERALLY A HALF TO
ONE INCH THROUGH EARLY EVENING. TWO INCHES OR MORE INCHES WILL BE
POSSIBLE IN THE HIGHEST TERRAIN NEAR THE VIRGINA BORDER THROUGH
MIDNIGHT. IN ADDITION TO THE SNOW...BRISK WINDS ACCOMPANYING THE SNOW
WILL LIMIT VISIBILITIES AT TIMES TO A MILE OR LESS...POTENTIALLY
CREATING BRIEF PERIODS OF HAZARDOUS TRAVEL. THE SNOW SHOWERS WILL
TAPER TO FLURRIES AND END FROM WEST TO EAST ON SATURDAY NIGHT WITH
TEMPERATURES PLUMMETING INTO THE TEENS BY DAWN. FOR THE BULK OF THE
DAY SATURDAY THE WX WILL BE QUIET BETWEEN DISTURBANCES. HOWEVER...BY
EVENING THICKER AND LOWER CLOUDS WILL BE ROLLING BACK IN FROM THE
NORTHWEST WITH SOME SNOW POSSIBLE BEFORE DARK IN OUR NORTHWEST
COUNTIES.
FOR THE ARCTIC BOUNDARY MOVING THROUGH THE CWA THIS MORNING AND
AFTERNOON WILL ISSUE AN EXTENSION TO THE WSW TO COVER THE ENTIRE
CWA...LINGERING IT INTO THE LATE EVENING IN THE FAR EAST. THE ONLY
DIFFERENCE FROM THE CURRENT ONE IS THAT THIS EXTENSION WILL NOT GO
INTO EFFECT UNTIL AFTER 15Z.
FOLLOWED A BLEND OF THE DIURNAL FROM NAM12 AND THE CONSSHORT FOR
HOURLY TEMPS WHILE FAVORED THE BCCONSSHORT FOR TD AND WINDS THROUGH
THE FIRST 24 HOURS...STARTING WITH THE CONSALL THEREAFTER AND FOR MAX
AND MIN TEMPS THROUGH SATURDAY. AS FOR POPS...ENDED UP HIGHER THAN
ALL GUIDANCE FOR TODAY THROUGH TONIGHT GIVEN THE LOW QPF NATURE OF
THIS EVENT.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 337 AM EST FRI JAN 17 2014
AN ACTIVE AND VERY PROGRESSIVE EXTENDED PERIOD BEGINS ON SATURDAY
NIGHT WITH A POSITIONED BROAD TROUGH OVER THE NORTHEASTERN CONUS AND
REMAINING THERE FOR THE ENTIRE EXTENDED. BEFORE DELVING INTO THE
SPECIFICS...THE MODELS DO AGREE ON A RIDGE TROUGH LONGWAVE PATTERN
THROUGH THE EXTENDED. THE TRUE FORECAST CHALLENGE FOR THIS PERIOD
FALLS ON HOW THE MODELS HANDLE THE ARRIVAL OF EACH SHORT WAVES THAT
WILL ROTATE DOWN OUT OF CANADA AND INTO THE GREAT LAKES OHIO VALLEY
REGION. THIS COUPLE WITH THE CHALLENGE OF DETERMINING THE MOISTURE
AVAILABLE...WILL BE QUITE A PROBLEM.
THIS IN MIND...WILL STAY CLOSE TO THE MODEL ALL BLEND AND ENSEMBLE
SOLUTIONS AND DECREASING PROBABILITIES WHERE CONFIDENCE IS LOW. THE
FIRST SIGNIFICANT WAVE MOVES THROUGH THE AREA ON SUNDAY. WITH THE
COLDER AIR ALREADY IN PLACE...THE PRECIP TYPE WITH THIS SYSTEM
SHOULD FALL AS SNOW AND THE INSTABILITY THE MODEL PROFILES ARE
SHOWING WOULD INDICATE AT SOME ACCUMULATING SNOWFALL POSSIBLE WITH
TEMPS COLD ENOUGH AND A GOOD SHOT OF OMEGA IN THE SATURATED -10 TO
-20 REGION FOR A GOOD 2 TO 3 HOUR PERIOD ON SUNDAY MORNING. WILL
NEED TO WATCH FOR THIS SYSTEM...ESPECIALLY WITH A FAVORABLE WIND
DIRECTION FOR SOME UP SLOPE ASSISTANCE. MODELS DO HAVE A GOOD BIT
AGREEMENT WITH THIS AND THIS WAVE IS POSSIBLY THE ONLY WAVE TO PUT
SOME CONFIDENCE IN AS AFTER THIS FEATURE MOVES THROUGH...THE MODELS
WAFFLE WITH THE CHARACTERISTICS OF THE SHORTWAVES LATER IN THE
EXTENDED.
AFTER THIS STRONG WAVE ON SUNDAY PUSHES THROUGH...A BUILDING ARCTIC
AIR MASS WILL DIVE SOUTH AS THE SEMI PERMANENT 500 TROUGH OVER THE
NORTHEAST DIGS A BIT FURTHER SOUTH INTO THE SOUTHERN APPALACHIANS.
THIS WILL BRING TEMPS INTO THE 20S FOR HIGHS AND TEENS FOR LOWS BY
TUESDAY AND THROUGH THE REST OF THE EXTENDED. THE FOLLOWING PIECES
OF ENERGY ON TUESDAY AND THURSDAY ARE QUITE WEAK AND EVEN THE EURO
IS INCONSISTENT WITH THESE WAVES AS IT WILL SHIFT THE WAVES ABOUT 1
TO 2 HUNDRED MILES TO THE EAST FROM RUN TO RUN. WITH THIS TYPE OF
INCONSISTENCY...HAVE GONE WITH SLIGHT CHANCE POPS FROM DAY 4 THROUGH
DAY 7. THE COLDER TEMPS EXPECTED THOUGH WILL ASSURE ANY PRECIP
FALLING AFTER DAY 4 WILL BE SNOW. IT IS SOMEWHAT ENCOURAGING THAT
TELECONNECTIONS AT THIS POINT SUPPORT FALLING TEMPS AFTER TUESDAY SO
THAT IS ONE PARAMETER THAT CAN BE COUNTED ON.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 135 PM EST FRI JAN 17 2014
CIGS AND OR VIS WILL DROP TO MVFR OR LOWER IN BANDS OF SNOW
SHOWERS THROUGH THE 21Z TO 2Z PERIOD...WITH SOME OCCASIONAL VIS AND
OR CIGS DOWN TO AIRPORT MINS. AFTER THAT...PREVAILING CIGS AND VIS
SHOULD GRADUALLY IMPROVE INTO THE VFR RANGE AS THE REGION WILL BE IN
A NARROW AREA OF RIDGING AS THE SYSTEM BRINGING THE CURRENT SHSN
DEPARTS AND IN ADVANCE OF THE NEXT SYSTEM APPROACHING FROM THE
NORTHWEST. WINDS WILL GENERALLY OUT OF THE WEST TO NORTHWEST AT 10 TO
AT TIMES 15KT AND SOME GUSTS AS HIGH AS 20 TO 25KT POSSIBLE. WINDS
SHOULD SLACK TO BELOW 10KT DURING THE 22Z TO 3Z PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR KYZ044-
050>052-058>060-068-069-079-080-104-106-108-111-114.
WINTER WEATHER ADVISORY UNTIL 11 PM EST THIS EVENING FOR KYZ087-
088-110-113-115-117-118-120.
WINTER WEATHER ADVISORY UNTIL 9 PM EST THIS EVENING FOR
KYZ083>086-107-109-112-116-119.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1048 AM EST FRI JAN 17 2014
.UPDATE...
ISSUED AT 1039 AM EST FRI JAN 17 2014
SNOW SHOWERS AND SOME ISOLATED SNOW SQUALLS ARE MOVING EAST SLIGHTLY
FASTER THAN THE PREVIOUS FORECAST. WE HAVE OPTED TO GO AHEAD AND
START THE WINTER WEATHER ADVISORY ACROSS THE SOUTHEASTERN PART OF THE
AREA A BIT QUICKER AS A RESULT. SNOW ACCUMULATIONS STILL LOOK GOOD
WITH AROUND AN INCH OR SO ON AVERAGE IN MOST LOCATIONS THROUGH THIS
EVENING. LOCALLY HIGHER AMOUNTS ARE ANTICIPATED GENERALLY ABOVE 2000
FEET NEARER TO VA AND IN ANY MORE PERSISTENT BANDS OF SNOW. ALTHOUGH
THERE WAS SOME THUNDERSNOW IN THE BAND OF SNOW SHOWERS NOW ROTATING
INTO VA AND WV...THE NEXT BANDS OF SNOW SHOWERS ARE NOT AS DEEP IN
THE ATMOSPHERE... AND LIGHTNING APPEARS LESS LIKELY BUT THEY SHOULD
BE MORE WIDESPREAD. HOURLY TEMPS AND DEWPOINTS HAVE ALSO BEEN
FRESHENED UP BASED ON THE LATEST TRENDS.
UPDATE ISSUED AT 620 AM EST FRI JAN 17 2014
DID A QUICK UPDATE TO TAKE THE FIRST ROUND OF SNOW OUT OF THE GRIDS
AND FIRM UP THE TIMING OF THE NEXT BATCH. ALSO FINE TUNED THE SKY AND
NEAR TERM TEMPS/DEWPOINTS. THESE HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 350 AM EST FRI JAN 17 2014
07Z SFC ANALYSIS SHOWS THE LATEST CLIPPER SYSTEM MOVING THROUGH THE
GREAT LAKES. THIS IS PUSHING AN ARCTIC BOUNDARY INTO THE WESTERN
PORTIONS OF THE OHIO VALLEY. AHEAD OF THIS...A DISTURBANCE AT MID
LEVELS HAS SENT A NEW BATCH OF SNOW SHOWERS THROUGH EAST KENTUCKY
WHITENING SOME PLACES UP TO AN INCH AS IT PASSES. AT THE WEATHER
OFFICE WE PICKED UP A QUICK 7 TENTHS OF AN INCH AS ONE OF THOSE BANDS
MOVED THROUGH. TEMPERATURES AROUND FREEZING AND ROAD TEMPERATURES IN
MOST PLACES ABOVE FREEZING WILL LIMIT THE IMPACT FROM THESE SNOW
SHOWERS. OVER THE SOUTHERN PARTS OF THE CUMBERLAND VALLEY THE
DEWPOINTS HAVE COME UP INTO THE LOW TO MID 30S AND THIS IS LEADING TO
MORE OF A RAIN EVENT WITH THIS ROUND RATHER THAN SNOW. IT IS A FINE
LINE...THOUGH...SO WILL CONTINUE THE SPS THAT IS OUT THROUGH 16Z FOR
THAT AREA. DESPITE A FEW HEAVIER BANDS...THE BULK OF THE AREA WILL
SEE AROUND A HALF AN INCH OF ACCUMULATION OR LESS THOUGH DAWN.
SLIGHTLY BETTER TOTALS CAN BE EXPECTED ALONG AND IN THE IMMEDIATE
WAKE OF THE ARCTIC BOUNDARY LATER TODAY.
THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT AS THEY ALL SHOW A
POTENT SHORTWAVE CROSSING THROUGH THE SOUTHERN OHIO VALLEY TODAY
WITHIN THE HEART OF A DEEP TROUGH. THIS WAVE WILL BRING SOME STEEP
LAPSE RATES TO THE LOWER PART OF THE ATMOSPHERE LATER THIS MORNING
AND THROUGH THE AFTERNOON HELPING TO ENHANCE THE LIFT AND SHOWERY
NATURE OF THE SNOW. THIS FEATURE MOVES QUICKLY OFF TO THE NORTHEAST
TONIGHT AS THE LARGER TROUGH TEMPORARILY RETREATS TO THE NORTH.
ACCORDINGLY...HEIGHTS WILL MODERATE THROUGH THE AREA INTO SATURDAY
MORNING. THIS PROCESS IS THEN QUICKLY REVERSED LATER THAT DAY AS THE
NEXT SHARP WAVE DROPS SOUTHEAST THROUGH THE MIDWEST...MAKING ITS RUN
TOWARD THE OHIO VALLEY. WITH THE GENERAL MODEL AGREEMENT AND THE
MESOSCALE NATURE OF THE SNOW BANDS AND ARCTIC BOUNDARY...HAVE LEANED
TOWARD THE HIGHER RESOLUTION HRRR AND NAM12 THROUGH THE SHORT TERM.
SENSIBLE WEATHER WILL FEATURE THE PRE-DAWN SNOW...AND FAR SOUTHERN
KY RAIN...SHOWERS EXITING THE AREA WITH A BIT OF A LULL IN ANY PCPN
ACTIVITY UNTIL AROUND MID MORNING IN THE WEST WHEN THE ARCTIC
BOUNDARY MOVES INTO THE CWA. THIS WILL BRING ANOTHER ROUND OF SNOW
SHOWERS...COLDER TEMPERATURES...AND BRISK WINDS TO THE AREA TODAY.
ALTHOUGH MOISTURE IS LIMITED WITH THIS...STILL EXPECT THE LIFT ALONG
THE FRONT AND STEEP LAPSE RATES BEHIND IT TO SUPPORT SNOW SHOWERS
INTENSE ENOUGH TO ACCUMULATE FOR MOST LOCATIONS...GENERALLY A HALF TO
ONE INCH THROUGH EARLY EVENING. TWO INCHES OR MORE INCHES WILL BE
POSSIBLE IN THE HIGHEST TERRAIN NEAR THE VIRGINA BORDER THROUGH
MIDNIGHT. IN ADDITION TO THE SNOW...BRISK WINDS ACCOMPANYING THE SNOW
WILL LIMIT VISIBILITIES AT TIMES TO A MILE OR LESS...POTENTIALLY
CREATING BRIEF PERIODS OF HAZARDOUS TRAVEL. THE SNOW SHOWERS WILL
TAPER TO FLURRIES AND END FROM WEST TO EAST ON SATURDAY NIGHT WITH
TEMPERATURES PLUMMETING INTO THE TEENS BY DAWN. FOR THE BULK OF THE
DAY SATURDAY THE WX WILL BE QUIET BETWEEN DISTURBANCES. HOWEVER...BY
EVENING THICKER AND LOWER CLOUDS WILL BE ROLLING BACK IN FROM THE
NORTHWEST WITH SOME SNOW POSSIBLE BEFORE DARK IN OUR NORTHWEST
COUNTIES.
FOR THE ARCTIC BOUNDARY MOVING THROUGH THE CWA THIS MORNING AND
AFTERNOON WILL ISSUE AN EXTENSION TO THE WSW TO COVER THE ENTIRE
CWA...LINGERING IT INTO THE LATE EVENING IN THE FAR EAST. THE ONLY
DIFFERENCE FROM THE CURRENT ONE IS THAT THIS EXTENSION WILL NOT GO
INTO EFFECT UNTIL AFTER 15Z.
FOLLOWED A BLEND OF THE DIURNAL FROM NAM12 AND THE CONSSHORT FOR
HOURLY TEMPS WHILE FAVORED THE BCCONSSHORT FOR TD AND WINDS THROUGH
THE FIRST 24 HOURS...STARTING WITH THE CONSALL THEREAFTER AND FOR MAX
AND MIN TEMPS THROUGH SATURDAY. AS FOR POPS...ENDED UP HIGHER THAN
ALL GUIDANCE FOR TODAY THROUGH TONIGHT GIVEN THE LOW QPF NATURE OF
THIS EVENT.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 337 AM EST FRI JAN 17 2014
AN ACTIVE AND VERY PROGRESSIVE EXTENDED PERIOD BEGINS ON SATURDAY
NIGHT WITH A POSITIONED BROAD TROUGH OVER THE NORTHEASTERN CONUS AND
REMAINING THERE FOR THE ENTIRE EXTENDED. BEFORE DELVING INTO THE
SPECIFICS...THE MODELS DO AGREE ON A RIDGE TROUGH LONGWAVE PATTERN
THROUGH THE EXTENDED. THE TRUE FORECAST CHALLENGE FOR THIS PERIOD
FALLS ON HOW THE MODELS HANDLE THE ARRIVAL OF EACH SHORT WAVES THAT
WILL ROTATE DOWN OUT OF CANADA AND INTO THE GREAT LAKES OHIO VALLEY
REGION. THIS COUPLE WITH THE CHALLENGE OF DETERMINING THE MOISTURE
AVAILABLE...WILL BE QUITE A PROBLEM.
THIS IN MIND...WILL STAY CLOSE TO THE MODEL ALL BLEND AND ENSEMBLE
SOLUTIONS AND DECREASING PROBABILITIES WHERE CONFIDENCE IS LOW. THE
FIRST SIGNIFICANT WAVE MOVES THROUGH THE AREA ON SUNDAY. WITH THE
COLDER AIR ALREADY IN PLACE...THE PRECIP TYPE WITH THIS SYSTEM
SHOULD FALL AS SNOW AND THE INSTABILITY THE MODEL PROFILES ARE
SHOWING WOULD INDICATE AT SOME ACCUMULATING SNOWFALL POSSIBLE WITH
TEMPS COLD ENOUGH AND A GOOD SHOT OF OMEGA IN THE SATURATED -10 TO
-20 REGION FOR A GOOD 2 TO 3 HOUR PERIOD ON SUNDAY MORNING. WILL
NEED TO WATCH FOR THIS SYSTEM...ESPECIALLY WITH A FAVORABLE WIND
DIRECTION FOR SOME UP SLOPE ASSISTANCE. MODELS DO HAVE A GOOD BIT
AGREEMENT WITH THIS AND THIS WAVE IS POSSIBLY THE ONLY WAVE TO PUT
SOME CONFIDENCE IN AS AFTER THIS FEATURE MOVES THROUGH...THE MODELS
WAFFLE WITH THE CHARACTERISTICS OF THE SHORTWAVES LATER IN THE
EXTENDED.
AFTER THIS STRONG WAVE ON SUNDAY PUSHES THROUGH...A BUILDING ARCTIC
AIR MASS WILL DIVE SOUTH AS THE SEMI PERMANENT 500 TROUGH OVER THE
NORTHEAST DIGS A BIT FURTHER SOUTH INTO THE SOUTHERN APPALACHIANS.
THIS WILL BRING TEMPS INTO THE 20S FOR HIGHS AND TEENS FOR LOWS BY
TUESDAY AND THROUGH THE REST OF THE EXTENDED. THE FOLLOWING PIECES
OF ENERGY ON TUESDAY AND THURSDAY ARE QUITE WEAK AND EVEN THE EURO
IS INCONSISTENT WITH THESE WAVES AS IT WILL SHIFT THE WAVES ABOUT 1
TO 2 HUNDRED MILES TO THE EAST FROM RUN TO RUN. WITH THIS TYPE OF
INCONSISTENCY...HAVE GONE WITH SLIGHT CHANCE POPS FROM DAY 4 THROUGH
DAY 7. THE COLDER TEMPS EXPECTED THOUGH WILL ASSURE ANY PRECIP
FALLING AFTER DAY 4 WILL BE SNOW. IT IS SOMEWHAT ENCOURAGING THAT
TELECONNECTIONS AT THIS POINT SUPPORT FALLING TEMPS AFTER TUESDAY SO
THAT IS ONE PARAMETER THAT CAN BE COUNTED ON.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 635 AM EST FRI JAN 17 2014
WE ARE NOW IN A LULL BETWEEN THESE SNOW SYSTEMS. THIS WILL RESULT IN
SPOTTY MVFR CIGS FOR THE NEXT SEVERAL HOURS...BUT GOOD VIS. THE CIGS
WILL LOWER MORE PERMANENTLY WITH THE ARRIVAL OF THE NEXT BATCH OF
SNOW. THIS NEXT BATCH OF SNOW WILL LAST THROUGH THE AFTERNOON WITH AN
ACCOMPANYING ARCTIC BOUNDARY ENOUGH FOR VIS AND CIGS TO FALL BACK
DOWN TO MVFR AND BRIEFLY WORSE. THIS LATEST AREA OF SNOW WILL
GRADUALLY WANE INTO THE EVENING WITH CIGS LIKELY IMPROVING AND VIS
ABOVE 6 MILES EVEN AS A FEW FLURRIES CONTINUE OVER THE AREA. WINDS
WILL BE SOUTHWEST AT 5 TO 10 KTS WITH AN OCCASIONAL GUST TO 15 KTS
UNTIL BETWEEN 15 AND 20Z WHEN THE BOUNDARY MOVES IN AND SWITCHES THEM
TO THE WEST AT 10 TO 20 KTS FOR THE BULK OF THE DAY...DIMINISHING
BELOW 10 KTS ONLY DURING THE EVENING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR KYZ044-
050>052-058>060-068-069-079-080-104-106-108-111-114.
WINTER WEATHER ADVISORY UNTIL 11 PM EST THIS EVENING FOR KYZ087-
088-110-113-115-117-118-120.
WINTER WEATHER ADVISORY UNTIL 9 PM EST THIS EVENING FOR
KYZ083>086-107-109-112-116-119.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
647 AM EST Fri Jan 17 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 645 AM EST Fri Jan 17 2014
Quick update to go a bit more bullish on snow coverage this morning,
and a little quicker with the timing as it is already starting to
expand into the Bluegrass region. Still look for the accumulating
snows to diminish from west to east around midday, but some concern
based on the NAM and RAP both showing a band hanging on into the
afternoon south of the Bluegrass Parkway.
Will try to handle specific trends mainly with Graphical Nowcasts
and social media. Overall zones and WSW look in good shape.
.SHORT TERM (Now through Saturday)...
Issued at 315 AM EST Fri Jan 17 2014
...Accumulating Snow Expected This Morning...
Main near-term challenge is how best to convey the potential impact
of snow showers this morning. Scattered snow showers over southwest
Indiana and western Kentucky have been increasing in coverage over
the last couple of hours, but significant gaps remain. Still can`t
count on where those gaps will be, but the leading edge of the snow
showers should reach the I-65 corridor around 6 AM EST, just in time
for the morning commute.
By far the most bullish QPF is generated by the 06Z NAM12, which
just came in. It actually has a decent handle on the ongoing precip,
and shows it blossoming enough to drop a tenth of an inch of liquid
in the Louisville Metro between 09-12Z, and liquid precip amounts
approaching two tenths up the I-71 corridor by 15Z. Not convinced we
will actually see that over any large area, but still believe there
is strong potential for a quick half inch of snow accumulation this
morning, with local amounts up to an inch. Will keep our current
Winter Weather Advisory flying more for impact than anything else.
If anything, with the axis of the 500mb shortwave trof pushing into
the I-75 corridor by mid-afternoon, could tinker with the end time
of the advisory.
Arctic front is right on the heels of these snow showers, and will
push through the area as the morning progresses. Temps currently
hovering near freezing will quickly drop into the 20s area-wide by
midday, then remain steady or continue to slowly fall through the
afternoon. Gusty northwest winds will make it feel more like 10
above this afternoon. Temp forecast is pretty much in line with raw
model consensus, and takes us a solid 10 degrees below normal
tonight and Saturday.
Next Clipper will approach the Ohio Valley from the NNW on Saturday
afternoon. Decent warm air advection ahead of this impulse will push
temps into the upper 30s in parts of south-central and west-central
Kentucky, but if precip moves in there will be sufficient wet-bulb
effect to get it to the surface as a rain/snow mix, if not all snow.
Could see a quick half inch of snow over southern Indiana, but it
should hold off until at least Saturday evening along and south of
the Western Kentucky and Bluegrass Parkways.
.LONG TERM (Saturday Night through Thursday)...
Issued at 315 AM EST Fri Jan 17 2014
The synoptic pattern at the start of the long term period will
feature amplified upper-level flow, with a trough dominating the
eastern 2/3rds of the CONUS. This stubborn pattern that we`ve seen
for several weeks now will continue through the long term period, as
the trough continually gets reinforced by quick-hitting PV anomalies
diving through the swift flow aloft.
A strong Clipper system approaching Saturday night will be the main
focus of the long term period. The latest guidance remains split on
the track of this system. The 17/00Z NAM/GEM advertise a southern
track, with the 17/00Z GFS/ECMWF advertise a more northerly
solution. The northerly solution would mean less snow for the
region, while the southerly solution would bring more in the way of
accumulations. Dprog/dt fields show the GFS and ECMWF solutions
being quite consistent, whereas the NAM has flopped to a more
southerly solution with the latest 00Z run. The GEFS agrees very
well with its deterministic solution, putting a bit more credence
within the northerly track. Additionally, climatology shows that
these fast-moving Clipper systems tend to produce the best swath of
snow just to the NE of the surface low track, where ascent from the
left exit region of the jet streak couples with the best mid-level
forcing to produce the best region of deep lift.
That being said, the northern solution still looks as if it could
bring some light accumulations to the region. The best chances of
exceeding an inch with this event will be across the Northern
Bluegrass and portions of eastern KY. It is in these locations
where the best QPF will combine with the highest snow ratios
(perhaps 15 to 20:1) to produce accumulations of around an inch.
Elsewhere, amounts look as if they`ll be a bit lower, given lower
QPF and warmer temperatures which will lead to a lower snow ratio.
The good news is that the snow looks as if it will mostly fall
Saturday evening into the first part of the overnight hours, which
should help minimize potential travel impacts.
The system will quickly push out Sunday morning, leading to clearing
skies. Temperatures behind it won`t be all that cool, with highs
Sunday expected in the upper 30s to lower 40s.
The upper trough briefly, very briefly, breaks down on Monday, which
will allow the flow to go more zonal. This should help temperatures
finally rise to near normal for this time of year, in the upper 30s
and 40s.
The trough builds back in by Tuesday and the forecast becomes tricky
for the remainder of next week as the train of quick-hitting PV
anomalies continues. Given the wet bias of guidance with these past
events, have trended the forecast on the drier side. That being
said, there will certainly be a few chances of some light snow
through the extended period as these systems pass through, but
nothing appears all that significant at this time. One weak system
looks possible Monday night into Tuesday, with another potential one
Wednesday night into Thursday. Confidence is quite high, however,
in below normal temperatures continuing through the extended as the
trough remains fixed over the region. High temperatures will
struggle in the middle 20s through much of next week, with lows
generally in the teens. For those craving spring, it seems that
winter still has a long way to go...
&&
.AVIATION (12Z TAF Update)...
Updated at 615 AM EST Fri Jan 17 2014
Cluster of snow showers has filled in over west central Kentucky,
and is now spreading into the SDF area, with visibilities
intermittently dropping to IFR. Through mid-morning SDF will be
impacted by these snow showers, which will be heavy enough at times
to drop visibilities into LIFR and allow snow to accumulate on
aircraft and runways. By about 14Z the focus will begin to shift
over to LEX, where we will face the same issues through midday. BWG
may be skirted by the tail end of this area of snow showers, but it
should be brief enough that it is not worthy of inclusion in the
TAF.
Cold front will move through by late morning, with the window for
snow showers coming to an end a couple hrs later as the upper
impulse finally moves to our east. Cig/vis will improve to VFR this
afternoon, with west winds kicking up to a solid 12-14 kt with gusts
around 20 kt. Look for winds to diminish after sunset as mixing is
lost.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WINTER WEATHER ADVISORY until 7 PM EST /6 PM CST/ this evening
FOR KYZ023>043-045>049-053>057-061>067.
IN...WINTER WEATHER ADVISORY until 7 PM EST /6 PM CST/ this evening
FOR INZ076>079-083-084-089>092.
&&
$$
Update.........RAS
Short Term.....RAS
Long Term......KJD
Aviation.......RAS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
635 AM EST FRI JAN 17 2014
.UPDATE...
ISSUED AT 620 AM EST FRI JAN 17 2014
DID A QUICK UPDATE TO TAKE THE FIRST ROUND OF SNOW OUT OF THE GRIDS
AND FIRM UP THE TIMING OF THE NEXT BATCH. ALSO FINE TUNED THE SKY AND
NEAR TERM TEMPS/DEWPOINTS. THESE HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 350 AM EST FRI JAN 17 2014
07Z SFC ANALYSIS SHOWS THE LATEST CLIPPER SYSTEM MOVING THROUGH THE
GREAT LAKES. THIS IS PUSHING AN ARCTIC BOUNDARY INTO THE WESTERN
PORTIONS OF THE OHIO VALLEY. AHEAD OF THIS...A DISTURBANCE AT MID
LEVELS HAS SENT A NEW BATCH OF SNOW SHOWERS THROUGH EAST KENTUCKY
WHITENING SOME PLACES UP TO AN INCH AS IT PASSES. AT THE WEATHER
OFFICE WE PICKED UP A QUICK 7 TENTHS OF AN INCH AS ONE OF THOSE BANDS
MOVED THROUGH. TEMPERATURES AROUND FREEZING AND ROAD TEMPERATURES IN
MOST PLACES ABOVE FREEZING WILL LIMIT THE IMPACT FROM THESE SNOW
SHOWERS. OVER THE SOUTHERN PARTS OF THE CUMBERLAND VALLEY THE
DEWPOINTS HAVE COME UP INTO THE LOW TO MID 30S AND THIS IS LEADING TO
MORE OF A RAIN EVENT WITH THIS ROUND RATHER THAN SNOW. IT IS A FINE
LINE...THOUGH...SO WILL CONTINUE THE SPS THAT IS OUT THROUGH 16Z FOR
THAT AREA. DESPITE A FEW HEAVIER BANDS...THE BULK OF THE AREA WILL
SEE AROUND A HALF AN INCH OF ACCUMULATION OR LESS THOUGH DAWN.
SLIGHTLY BETTER TOTALS CAN BE EXPECTED ALONG AND IN THE IMMEDIATE
WAKE OF THE ARCTIC BOUNDARY LATER TODAY.
THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT AS THEY ALL SHOW A
POTENT SHORTWAVE CROSSING THROUGH THE SOUTHERN OHIO VALLEY TODAY
WITHIN THE HEART OF A DEEP TROUGH. THIS WAVE WILL BRING SOME STEEP
LAPSE RATES TO THE LOWER PART OF THE ATMOSPHERE LATER THIS MORNING
AND THROUGH THE AFTERNOON HELPING TO ENHANCE THE LIFT AND SHOWERY
NATURE OF THE SNOW. THIS FEATURE MOVES QUICKLY OFF TO THE NORTHEAST
TONIGHT AS THE LARGER TROUGH TEMPORARILY RETREATS TO THE NORTH.
ACCORDINGLY...HEIGHTS WILL MODERATE THROUGH THE AREA INTO SATURDAY
MORNING. THIS PROCESS IS THEN QUICKLY REVERSED LATER THAT DAY AS THE
NEXT SHARP WAVE DROPS SOUTHEAST THROUGH THE MIDWEST...MAKING ITS RUN
TOWARD THE OHIO VALLEY. WITH THE GENERAL MODEL AGREEMENT AND THE
MESOSCALE NATURE OF THE SNOW BANDS AND ARCTIC BOUNDARY...HAVE LEANED
TOWARD THE HIGHER RESOLUTION HRRR AND NAM12 THROUGH THE SHORT TERM.
SENSIBLE WEATHER WILL FEATURE THE PRE-DAWN SNOW...AND FAR SOUTHERN
KY RAIN...SHOWERS EXITING THE AREA WITH A BIT OF A LULL IN ANY PCPN
ACTIVITY UNTIL AROUND MID MORNING IN THE WEST WHEN THE ARCTIC
BOUNDARY MOVES INTO THE CWA. THIS WILL BRING ANOTHER ROUND OF SNOW
SHOWERS...COLDER TEMPERATURES...AND BRISK WINDS TO THE AREA TODAY.
ALTHOUGH MOISTURE IS LIMITED WITH THIS...STILL EXPECT THE LIFT ALONG
THE FRONT AND STEEP LAPSE RATES BEHIND IT TO SUPPORT SNOW SHOWERS
INTENSE ENOUGH TO ACCUMULATE FOR MOST LOCATIONS...GENERALLY A HALF TO
ONE INCH THROUGH EARLY EVENING. TWO INCHES OR MORE INCHES WILL BE
POSSIBLE IN THE HIGHEST TERRAIN NEAR THE VIRGINA BORDER THROUGH
MIDNIGHT. IN ADDITION TO THE SNOW...BRISK WINDS ACCOMPANYING THE SNOW
WILL LIMIT VISIBILITIES AT TIMES TO A MILE OR LESS...POTENTIALLY
CREATING BRIEF PERIODS OF HAZARDOUS TRAVEL. THE SNOW SHOWERS WILL
TAPER TO FLURRIES AND END FROM WEST TO EAST ON SATURDAY NIGHT WITH
TEMPERATURES PLUMMETING INTO THE TEENS BY DAWN. FOR THE BULK OF THE
DAY SATURDAY THE WX WILL BE QUIET BETWEEN DISTURBANCES. HOWEVER...BY
EVENING THICKER AND LOWER CLOUDS WILL BE ROLLING BACK IN FROM THE
NORTHWEST WITH SOME SNOW POSSIBLE BEFORE DARK IN OUR NORTHWEST
COUNTIES.
FOR THE ARCTIC BOUNDARY MOVING THROUGH THE CWA THIS MORNING AND
AFTERNOON WILL ISSUE AN EXTENSION TO THE WSW TO COVER THE ENTIRE
CWA...LINGERING IT INTO THE LATE EVENING IN THE FAR EAST. THE ONLY
DIFFERENCE FROM THE CURRENT ONE IS THAT THIS EXTENSION WILL NOT GO
INTO EFFECT UNTIL AFTER 15Z.
FOLLOWED A BLEND OF THE DIURNAL FROM NAM12 AND THE CONSSHORT FOR
HOURLY TEMPS WHILE FAVORED THE BCCONSSHORT FOR TD AND WINDS THROUGH
THE FIRST 24 HOURS...STARTING WITH THE CONSALL THEREAFTER AND FOR MAX
AND MIN TEMPS THROUGH SATURDAY. AS FOR POPS...ENDED UP HIGHER THAN
ALL GUIDANCE FOR TODAY THROUGH TONIGHT GIVEN THE LOW QPF NATURE OF
THIS EVENT.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 337 AM EST FRI JAN 17 2014
AN ACTIVE AND VERY PROGRESSIVE EXTENDED PERIOD BEGINS ON SATURDAY
NIGHT WITH A POSITIONED BROAD TROUGH OVER THE NORTHEASTERN CONUS AND
REMAINING THERE FOR THE ENTIRE EXTENDED. BEFORE DELVING INTO THE
SPECIFICS...THE MODELS DO AGREE ON A RIDGE TROUGH LONGWAVE PATTERN
THROUGH THE EXTENDED. THE TRUE FORECAST CHALLENGE FOR THIS PERIOD
FALLS ON HOW THE MODELS HANDLE THE ARRIVAL OF EACH SHORT WAVES THAT
WILL ROTATE DOWN OUT OF CANADA AND INTO THE GREAT LAKES OHIO VALLEY
REGION. THIS COUPLE WITH THE CHALLENGE OF DETERMINING THE MOISTURE
AVAILABLE...WILL BE QUITE A PROBLEM.
THIS IN MIND...WILL STAY CLOSE TO THE MODEL ALL BLEND AND ENSEMBLE
SOLUTIONS AND DECREASING PROBABILITIES WHERE CONFIDENCE IS LOW. THE
FIRST SIGNIFICANT WAVE MOVES THROUGH THE AREA ON SUNDAY. WITH THE
COLDER AIR ALREADY IN PLACE...THE PRECIP TYPE WITH THIS SYSTEM
SHOULD FALL AS SNOW AND THE INSTABILITY THE MODEL PROFILES ARE
SHOWING WOULD INDICATE AT SOME ACCUMULATING SNOWFALL POSSIBLE WITH
TEMPS COLD ENOUGH AND A GOOD SHOT OF OMEGA IN THE SATURATED -10 TO
-20 REGION FOR A GOOD 2 TO 3 HOUR PERIOD ON SUNDAY MORNING. WILL
NEED TO WATCH FOR THIS SYSTEM...ESPECIALLY WITH A FAVORABLE WIND
DIRECTION FOR SOME UP SLOPE ASSISTANCE. MODELS DO HAVE A GOOD BIT
AGREEMENT WITH THIS AND THIS WAVE IS POSSIBLY THE ONLY WAVE TO PUT
SOME CONFIDENCE IN AS AFTER THIS FEATURE MOVES THROUGH...THE MODELS
WAFFLE WITH THE CHARACTERISTICS OF THE SHORTWAVES LATER IN THE
EXTENDED.
AFTER THIS STRONG WAVE ON SUNDAY PUSHES THROUGH...A BUILDING ARCTIC
AIR MASS WILL DIVE SOUTH AS THE SEMI PERMANENT 500 TROUGH OVER THE
NORTHEAST DIGS A BIT FURTHER SOUTH INTO THE SOUTHERN APPALACHIANS.
THIS WILL BRING TEMPS INTO THE 20S FOR HIGHS AND TEENS FOR LOWS BY
TUESDAY AND THROUGH THE REST OF THE EXTENDED. THE FOLLOWING PIECES
OF ENERGY ON TUESDAY AND THURSDAY ARE QUITE WEAK AND EVEN THE EURO
IS INCONSISTENT WITH THESE WAVES AS IT WILL SHIFT THE WAVES ABOUT 1
TO 2 HUNDRED MILES TO THE EAST FROM RUN TO RUN. WITH THIS TYPE OF
INCONSISTENCY...HAVE GONE WITH SLIGHT CHANCE POPS FROM DAY 4 THROUGH
DAY 7. THE COLDER TEMPS EXPECTED THOUGH WILL ASSURE ANY PRECIP
FALLING AFTER DAY 4 WILL BE SNOW. IT IS SOMEWHAT ENCOURAGING THAT
TELECONNECTIONS AT THIS POINT SUPPORT FALLING TEMPS AFTER TUESDAY SO
THAT IS ONE PARAMETER THAT CAN BE COUNTED ON.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 635 AM EST FRI JAN 17 2014
WE ARE NOW IN A LULL BETWEEN THESE SNOW SYSTEMS. THIS WILL RESULT IN
SPOTTY MVFR CIGS FOR THE NEXT SEVERAL HOURS...BUT GOOD VIS. THE CIGS
WILL LOWER MORE PERMANENTLY WITH THE ARRIVAL OF THE NEXT BATCH OF
SNOW. THIS NEXT BATCH OF SNOW WILL LAST THROUGH THE AFTERNOON WITH AN
ACCOMPANYING ARCTIC BOUNDARY ENOUGH FOR VIS AND CIGS TO FALL BACK
DOWN TO MVFR AND BRIEFLY WORSE. THIS LATEST AREA OF SNOW WILL
GRADUALLY WANE INTO THE EVENING WITH CIGS LIKELY IMPROVING AND VIS
ABOVE 6 MILES EVEN AS A FEW FLURRIES CONTINUE OVER THE AREA. WINDS
WILL BE SOUTHWEST AT 5 TO 10 KTS WITH AN OCCASIONAL GUST TO 15 KTS
UNTIL BETWEEN 15 AND 20Z WHEN THE BOUNDARY MOVES IN AND SWITCHES THEM
TO THE WEST AT 10 TO 20 KTS FOR THE BULK OF THE DAY...DIMINISHING
BELOW 10 KTS ONLY DURING THE EVENING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR KYZ044-
050>052-058>060-068-069-079-080-104-106-108-111-114.
WINTER WEATHER ADVISORY FROM NOON TODAY TO MIDNIGHT EST TONIGHT
FOR KYZ087-088-110-113-115-117-118-120.
WINTER WEATHER ADVISORY UNTIL 9 PM EST THIS EVENING FOR
KYZ083>086-107-109-112-116-119.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
351 AM EST FRI JAN 17 2014
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 350 AM EST FRI JAN 17 2014
07Z SFC ANALYSIS SHOWS THE LATEST CLIPPER SYSTEM MOVING THROUGH THE
GREAT LAKES. THIS IS PUSHING AN ARCTIC BOUNDARY INTO THE WESTERN
PORTIONS OF THE OHIO VALLEY. AHEAD OF THIS...A DISTURBANCE AT MID
LEVELS HAS SENT A NEW BATCH OF SNOW SHOWERS THROUGH EAST KENTUCKY
WHITENING SOME PLACES UP TO AN INCH AS IT PASSES. AT THE WEATHER
OFFICE WE PICKED UP A QUICK 7 TENTHS OF AN INCH AS ONE OF THOSE BANDS
MOVED THROUGH. TEMPERATURES AROUND FREEZING AND ROAD TEMPERATURES IN
MOST PLACES ABOVE FREEZING WILL LIMIT THE IMPACT FROM THESE SNOW
SHOWERS. OVER THE SOUTHERN PARTS OF THE CUMBERLAND VALLEY THE
DEWPOINTS HAVE COME UP INTO THE LOW TO MID 30S AND THIS IS LEADING TO
MORE OF A RAIN EVENT WITH THIS ROUND RATHER THAN SNOW. IT IS A FINE
LINE...THOUGH...SO WILL CONTINUE THE SPS THAT IS OUT THROUGH 16Z FOR
THAT AREA. DESPITE A FEW HEAVIER BANDS...THE BULK OF THE AREA WILL
SEE AROUND A HALF AN INCH OF ACCUMULATION OR LESS THOUGH DAWN.
SLIGHTLY BETTER TOTALS CAN BE EXPECTED ALONG AND IN THE IMMEDIATE
WAKE OF THE ARCTIC BOUNDARY LATER TODAY.
THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT AS THEY ALL SHOW A
POTENT SHORTWAVE CROSSING THROUGH THE SOUTHERN OHIO VALLEY TODAY
WITHIN THE HEART OF A DEEP TROUGH. THIS WAVE WILL BRING SOME STEEP
LAPSE RATES TO THE LOWER PART OF THE ATMOSPHERE LATER THIS MORNING
AND THROUGH THE AFTERNOON HELPING TO ENHANCE THE LIFT AND SHOWERY
NATURE OF THE SNOW. THIS FEATURE MOVES QUICKLY OFF TO THE NORTHEAST
TONIGHT AS THE LARGER TROUGH TEMPORARILY RETREATS TO THE NORTH.
ACCORDINGLY...HEIGHTS WILL MODERATE THROUGH THE AREA INTO SATURDAY
MORNING. THIS PROCESS IS THEN QUICKLY REVERSED LATER THAT DAY AS THE
NEXT SHARP WAVE DROPS SOUTHEAST THROUGH THE MIDWEST...MAKING ITS RUN
TOWARD THE OHIO VALLEY. WITH THE GENERAL MODEL AGREEMENT AND THE
MESOSCALE NATURE OF THE SNOW BANDS AND ARCTIC BOUNDARY...HAVE LEANED
TOWARD THE HIGHER RESOLUTION HRRR AND NAM12 THROUGH THE SHORT TERM.
SENSIBLE WEATHER WILL FEATURE THE PRE-DAWN SNOW...AND FAR SOUTHERN
KY RAIN...SHOWERS EXITING THE AREA WITH A BIT OF A LULL IN ANY PCPN
ACTIVITY UNTIL AROUND MID MORNING IN THE WEST WHEN THE ARCTIC
BOUNDARY MOVES INTO THE CWA. THIS WILL BRING ANOTHER ROUND OF SNOW
SHOWERS...COLDER TEMPERATURES...AND BRISK WINDS TO THE AREA TODAY.
ALTHOUGH MOISTURE IS LIMITED WITH THIS...STILL EXPECT THE LIFT ALONG
THE FRONT AND STEEP LAPSE RATES BEHIND IT TO SUPPORT SNOW SHOWERS
INTENSE ENOUGH TO ACCUMULATE FOR MOST LOCATIONS...GENERALLY A HALF TO
ONE INCH THROUGH EARLY EVENING. TWO INCHES OR MORE INCHES WILL BE
POSSIBLE IN THE HIGHEST TERRAIN NEAR THE VIRGINA BORDER THROUGH
MIDNIGHT. IN ADDITION TO THE SNOW...BRISK WINDS ACCOMPANYING THE SNOW
WILL LIMIT VISIBILITIES AT TIMES TO A MILE OR LESS...POTENTIALLY
CREATING BRIEF PERIODS OF HAZARDOUS TRAVEL. THE SNOW SHOWERS WILL
TAPER TO FLURRIES AND END FROM WEST TO EAST ON SATURDAY NIGHT WITH
TEMPERATURES PLUMMETING INTO THE TEENS BY DAWN. FOR THE BULK OF THE
DAY SATURDAY THE WX WILL BE QUIET BETWEEN DISTURBANCES. HOWEVER...BY
EVENING THICKER AND LOWER CLOUDS WILL BE ROLLING BACK IN FROM THE
NORTHWEST WITH SOME SNOW POSSIBLE BEFORE DARK IN OUR NORTHWEST
COUNTIES.
FOR THE ARCTIC BOUNDARY MOVING THROUGH THE CWA THIS MORNING AND
AFTERNOON WILL ISSUE AN EXTENSION TO THE WSW TO COVER THE ENTIRE
CWA...LINGERING IT INTO THE LATE EVENING IN THE FAR EAST. THE ONLY
DIFFERENCE FROM THE CURRENT ONE IS THAT THIS EXTENSION WILL NOT GO
INTO EFFECT UNTIL AFTER 15Z.
FOLLOWED A BLEND OF THE DIURNAL FROM NAM12 AND THE CONSSHORT FOR
HOURLY TEMPS WHILE FAVORED THE BCCONSSHORT FOR TD AND WINDS THROUGH
THE FIRST 24 HOURS...STARTING WITH THE CONSALL THEREAFTER AND FOR MAX
AND MIN TEMPS THROUGH SATURDAY. AS FOR POPS...ENDED UP HIGHER THAN
ALL GUIDANCE FOR TODAY THROUGH TONIGHT GIVEN THE LOW QPF NATURE OF
THIS EVENT.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 337 AM EST FRI JAN 17 2014
AN ACTIVE AND VERY PROGRESSIVE EXTENDED PERIOD BEGINS ON SATURDAY
NIGHT WITH A POSITIONED BROAD TROUGH OVER THE NORTHEASTERN CONUS AND
REMAINING THERE FOR THE ENTIRE EXTENDED. BEFORE DELVING INTO THE
SPECIFICS...THE MODELS DO AGREE ON A RIDGE TROUGH LONGWAVE PATTERN
THROUGH THE EXTENDED. THE TRUE FORECAST CHALLENGE FOR THIS PERIOD
FALLS ON HOW THE MODELS HANDLE THE ARRIVAL OF EACH SHORT WAVES THAT
WILL ROTATE DOWN OUT OF CANADA AND INTO THE GREAT LAKES OHIO VALLEY
REGION. THIS COUPLE WITH THE CHALLENGE OF DETERMINING THE MOISTURE
AVAILABLE...WILL BE QUITE A PROBLEM.
THIS IN MIND...WILL STAY CLOSE TO THE MODEL ALL BLEND AND ENSEMBLE
SOLUTIONS AND DECREASING PROBABILITIES WHERE CONFIDENCE IS LOW. THE
FIRST SIGNIFICANT WAVE MOVES THROUGH THE AREA ON SUNDAY. WITH THE
COLDER AIR ALREADY IN PLACE...THE PRECIP TYPE WITH THIS SYSTEM
SHOULD FALL AS SNOW AND THE INSTABILITY THE MODEL PROFILES ARE
SHOWING WOULD INDICATE AT SOME ACCUMULATING SNOWFALL POSSIBLE WITH
TEMPS COLD ENOUGH AND A GOOD SHOT OF OMEGA IN THE SATURATED -10 TO
-20 REGION FOR A GOOD 2 TO 3 HOUR PERIOD ON SUNDAY MORNING. WILL
NEED TO WATCH FOR THIS SYSTEM...ESPECIALLY WITH A FAVORABLE WIND
DIRECTION FOR SOME UP SLOPE ASSISTANCE. MODELS DO HAVE A GOOD BIT
AGREEMENT WITH THIS AND THIS WAVE IS POSSIBLY THE ONLY WAVE TO PUT
SOME CONFIDENCE IN AS AFTER THIS FEATURE MOVES THROUGH...THE MODELS
WAFFLE WITH THE CHARACTERISTICS OF THE SHORTWAVES LATER IN THE
EXTENDED.
AFTER THIS STRONG WAVE ON SUNDAY PUSHES THROUGH...A BUILDING ARCTIC
AIR MASS WILL DIVE SOUTH AS THE SEMI PERMANENT 500 TROUGH OVER THE
NORTHEAST DIGS A BIT FURTHER SOUTH INTO THE SOUTHERN APPALACHIANS.
THIS WILL BRING TEMPS INTO THE 20S FOR HIGHS AND TEENS FOR LOWS BY
TUESDAY AND THROUGH THE REST OF THE EXTENDED. THE FOLLOWING PIECES
OF ENERGY ON TUESDAY AND THURSDAY ARE QUITE WEAK AND EVEN THE EURO
IS INCONSISTENT WITH THESE WAVES AS IT WILL SHIFT THE WAVES ABOUT 1
TO 2 HUNDRED MILES TO THE EAST FROM RUN TO RUN. WITH THIS TYPE OF
INCONSISTENCY...HAVE GONE WITH SLIGHT CHANCE POPS FROM DAY 4 THROUGH
DAY 7. THE COLDER TEMPS EXPECTED THOUGH WILL ASSURE ANY PRECIP
FALLING AFTER DAY 4 WILL BE SNOW. IT IS SOMEWHAT ENCOURAGING THAT
TELECONNECTIONS AT THIS POINT SUPPORT FALLING TEMPS AFTER TUESDAY SO
THAT IS ONE PARAMETER THAT CAN BE COUNTED ON.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1255 AM EST FRI JAN 17 2014
THE NEXT ROUND OF SNOW IS INBOUND TO THE SOUTHERN TAFS AND WILL
OVERSPREAD THE REST OF THE AREA DURING THE NEXT SEVERAL HOURS. WITH
THIS...CIGS WILL GRADUALLY FALL TO THE MVFR RANGE BY 09Z. A LULL IN
THE LOWER CLOUDS AND PCPN WILL THEN FOLLOW INTO MID AND LATE MORNING
HOURS OF FRIDAY SO THAT THERE MAY BE LITTLE IN THE WAY OF VIS OR CIG
RESTRICTIONS. HOWEVER...ANOTHER BATCH OF SNOW LASTING DURING THE
AFTERNOON FRIDAY WITH AN ACCOMPANYING ARCTIC BOUNDARY SHOULD BE
ENOUGH FOR VIS AND CIGS TO FALL BACK DOWN TO MVFR AND BRIEFLY WORSE.
THIS LAST AREA OF SNOW WILL GRADUALLY WANE INTO THE EVENING WITH CIGS
LIKELY IMPROVING AND VIS ABOVE 6 MILES EVEN AS A FEW FLURRIES
CONTINUE OVER THE AREA. WINDS WILL BE SOUTHWEST AT 5 TO 10 KTS WITH
AN OCCASIONAL GUST TO 15 KTS UNTIL AROUND 15Z WHEN THE BOUNDARY
MOVES IN AND SWITCHES THEM TO THE WEST AT 10 TO 20 KTS FOR THE BULK
OF THE DAY...DIMINISHING BELOW 10 KTS ONLY DURING THE EVENING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR KYZ044-
050>052-058>060-068-069-079-080-104-106-108-111-114.
WINTER WEATHER ADVISORY FROM NOON TODAY TO MIDNIGHT EST TONIGHT
FOR KYZ087-088-110-113-115-117-118-120.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 9 PM EST THIS
EVENING FOR KYZ083>086-107-109-112-116-119.
&&
$$
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1002 PM EST SAT JAN 18 2014
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVERHEAD THROUGH THIS EVENING. A CLIPPER
SYSTEM MOVES THROUGH MID-ATLANTIC REGION LATE TONIGHT AND SUNDAY
MORNING. AN ARCTIC COLD FRONT WILL PASS THROUGH MONDAY AFTERNOON
AND NIGHT. HIGH PRESSURE BUILDS OVERHEAD MIDWEEK.
&&
.NEAR TERM /THROUGH SUNDAY NIGHT/...
WEAK HIGH PRESSURE OVER THE AREA LATE THIS EVENING WILL MOVE
OFFSHORE TONIGHT AS A CLIPPER SYSTEM APPROACHES FROM THE WEST. 02Z
MSAS ANALYSIS INDICATES THIS LOW CONTINUES TO GRADUALLY WEAKEN AS
IT TRAVERSES THE WESTERN OHIO RIVER VALLEY. THIS TREND IS
EXPECTED TO CONTINUE TONIGHT AS THE LOW APPROACHES FROM THE WEST.
A BROAD AREA OF LIGHT SNOW HAS OVERSPREAD WESTERN AND SRN
WV...WITH A BAND OF MODERATE-HEAVY SNOW AND 1-2SM VSBYS OVER WRN
WV AND SERN OHIO.
SNOW IS EXPECTED TO REACH THE WRN HIGHLANDS TOWARDS MIDNIGHT
BEFORE MOVING EWD LATE TNGT INTO SUN MRNG. ALTHOUGH CONFIDENCE IS
HIGH OF SNOW CONTINUING OVER THE HIGHLANDS...UNCERTAINTY REMAINS
AS TO HOW MUCH FURTHER EAST ACCUMULATING SNOW WILL MAKE IT
TONIGHT. 00Z NAM HAS COME IN WITH VERY LITTLE EAST OF THE POTOMAC
HIGHLANDS/ALLEGANY FRONT...WITH THE SURFACE LOW BECOMING MORE OF A
WAVE AS IT CROSSES WV. HRRR IS A LITTLE MORE ROBUST WITH CHANCES
OF SNOW MAKING IT FURTHER EAST. FCST THERMAL PROFILES FOR TNGT DO
NOT SHOW THE STEEP LAPSE RATES THAT WERE OBSERVED LAST NGT WHICH
HELPED MAINTAIN SNOW SHOWERS ON THE EAST SIDE OF THE BLUE RIDGE.
UPPER SUPPORT WILL ALSO WEAKEN A BIT AS IT MOVES BC THE LOW/TROUGH
WILL SHEAR OUT.
FORECAST UPDATES THIS EVENING INCLUDE MODEST INCREASES IN
SNOWFALL TOTALS EAST OF THE BLUE RIDGE. STILL EXPECTING 1-3
INCHES ALONG THE ALLEGHENY FRONT...AND LESS THAN ONE INCH
FROM THE EASTERN SLOPES ACROSS THE EASTERN WV PANHANDLE...THE BLUE
RIDGE AND NRN MD. GIVEN THE LACK OF INSTABILITY AND LESS THAN
IDEAL UPSLOPE TRAJECTORY (SWLY WINDS IN THE BOUNDARY LAYER) BEHIND
THE TROUGH PASSAGE...WILL HOLD OFF ON ISSUING A WINTER WEATHER
ADVISORY FOR THE WRN MOST ZONES.
SNOW SHOWERS/FLURRIES WILL END AND SKIES CLEAR FROM WEST TO EAST
DURING THE MRNG AS THE TROUGH PROGRESSES EASTWARD. ITS HARD TO CALL
THIS TROUGH PASSAGE A COLD FRONT WITH NO COLDER AIR IN ITS WAKE. IN
FACT...WAA AND DOWNSLOPING WINDS OFF THE MTS WILL ALLOW FOR HIGHS IN
THE 40S ACROSS MOST OF THE AREA.
A LGT SLY FLOW WILL DEVELOP SUN NGT AHEAD OF THE NEXT DISTURBANCE
THAT WILL BE APPROACHING FROM THE GREAT LAKES. MIN TEMPS IN THE
20S WILL BE COMMON.
&&
.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
A COLD FRONT SHOULD BE LOCATED ACROSS NY/PA MONDAY AFTERNOON AND SW
FLOW WILL LET THE MID ATLANTIC REACH TEMPS IN THE 40S AND 50S IN
CENTRAL VA. THESE TEMPS WILL BE THE WARMEST TEMPS IN THE 7 DAY
PERIOD. AS THE COLD FRONT MOVES SOUTH MONDAY AFTERNOON NORTHERLY
WINDS WILL BRING COLDER TEMPS INTO THE REGION. THIS FROPA IS ONLY
EXPECTED TO BRING SNOW FOR THE UPSLOPE REGION PRODUCING ANOTHER
ROUND OF LIGHT ACCUMULATION. TEMPS WILL DROP TO THE MID 20S INTO
TUESDAY MORNING AS A LONGWAVE TROUGH APPROACHES FROM THE NORTHWEST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AN ARCTIC AIRMASS WILL MOVE IN BEHIND THE COLD FRONT TUESDAY
MORNING. TEMPERATURES WILL BE WELL BELOW NORMAL THROUGH THE MIDDLE
OF THE WEEK AS MANY PLACES WILL STRUGGLE TO GET BACK ABOVE FREEZING
UNTIL THE WEEKEND. THERE IS DECENT AGREEMENT AMONGST THE MODELS FOR
AN UPPER LEVEL VORTICITY MAX AND ASSOCIATED WEAK SFC TROF TO MOVE
THROUGH THE MID ATLANTIC DURING THE DAY ON TUESDAY. CURRENT THINKING
IS THAT THIS WILL BE A LOW QPF EVENT WITH ALL PRECIPITATION FALLING
IN THE FORM OF SNOW DUE TO PLENTY OF CAA IN THE LOWER LEVELS. EXACT
LOCATION OF THE DISTURBANCE IS STILL UNCERTAIN WITH THE GFS AND EURO
BRINGING IT OVER OUR AREA AND THE NAM KEEPING IT TO OUR SOUTH. AS
THIS VORT MAX PROGRESSES EASTWARD IT IS EXPECTED TO DEVELOP AN
ATTENDANT SURFACE LOW OFF OF THE NORTH CAROLINA COAST TUESDAY
AFTERNOON. THIS COASTAL LOW WILL REMAIN WELL OFF THE COAST AS IT
DEEPENS AND MOVES NEWRD THROUGH THE NIGHT ON TUESDAY. EXPECT LITTLE
IMPACT LOCALLY ASIDE FROM A TIGHTENED PRESSURE GRADIENT LEADING TO
BREEZY WINDS AND POTENTIALLY HAZARDOUS MARINE CONDITIONS.
HIGH PRESSURE WILL BUILD IN BRIEFLY DURING THE DAY ON WEDNESDAY
BEFORE A LOW PRESSURE SYSTEM EFFECTS THE AREA LATE WEDNESDAY NIGHT
AND THURSDAY MORNING. THE EXACT TRACK AND STRENGTH OF THIS SYSTEM IS
STILL UNCERTAIN...BUT WITH THE SURFACE COLD AIR MASS FIRMLY IN PLACE
OVER THE EASTERN US EVEN THE WARM SECTOR OF THE LOW SHOULD BE BELOW
FREEZING. CONFIDENCE IS LOW IN THE TIMING AND EXTENT OF WINTRY
PRECIPITATION AT THIS TIME. THIS LOW WILL DEEPEN AS IT MOVES OFF THE
COAST AND BREEZY WINDS ARE ONCE AGAIN POSSIBLE FOR THE END OF THE
WORKWEEK. HIGH PRESSURE WILL BRING MORE SEASONABLE TEMPS AS IT
BUILDS BACK IN NEXT WEEKEND.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
CLOUDS INCREASE AND CIGS LOWER LATE TNGT AS A CLIPPER SYSTEM
APPROACHES. CURRENTLY KMRB IS THE ONLY TERMINAL WITH FCST MVFR
CONDITIONS AND LIGHT SNOW...BUT CANNOT RULE OUT A BRIEF PERIOD OF
SHSN OR FLURRIES BETWEEN ABOUT 06Z-12Z SUN IN VC OF CHO/IAD AND
09Z- 15Z SUN IN VC OF DCA/BWI/MTN. ANY MENTION OF SHSN AND REDUCED
VSBYS CONFINED TO WRN MOST TERMINALS. OTHERWISE VFR CONDITIONS.
LIGHT WINDS TONIGHT. THEN INCREASING OUT OF THE WEST SUNDAY. GUSTS
20-25 KT EXPECTED SUN AFTN.
SUB VFR CONDITIONS ARE POSSIBLE DURING POTENTIAL PERIODS OF SNOW
DURING THE DAY TUESDAY...AND WEDNESDAY NIGHT INTO THURSDAY
MORNING.
&&
.MARINE...
SOME GUSTS UP TO AROUND 20KTS HAVE LINGERED OVER PORTIONS
CHESAPEAKE BAY AND BALTIMORE HARBOR...SO MARINE WEATHER STATEMENT
HAS BEEN ISSUED UNTIL 9PM. WINDS ARE EXPECTED TO DIMINISH BY LATE
EVENING AS A LOW LEVEL JET MOVES EAST TOWARDS THE ATLANTIC.
SCA ISSUED FOR SUN WHEN W-SW WINDS INCREASE BEHIND A TROUGH THAT
PASSES THRU THE WATERS DURING THE MRNG. SCA EXTENDED INTO SUN NGT
FOR THE MID CHSPK BAY AND LWR TIDAL POTOMAC RVR.
KEPT WINDS JUST BELOW SCA LVLS ON MON. WINDS INCREASE BEHIND A
COLD FRONT MON NGT. SCA MAY BE NEEDED FOR MON NGT.
A SMALL CRAFT ADVISORY WILL LIKELY BE NECESSARY FOR STRONG NORTH
WINDS FROM TUESDAY MORNING THROUGH WEDNESDAY AFTERNOON AND THEN
AGAIN THURSDAY NIGHT THOUGH FRIDAY EVENING AS DEEPENING COASTAL LOWS
MOVE AWAY FROM THE MID ATLANTIC.
SUB-VFR CONDITIONS ARE POSSIBLE DURING PERIODS OF LGT SNOW
TUESDAY...AND WEDNESDAY NIGHT INTO THURSDAY MORNING.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM NOON TO 6 PM EST SUNDAY FOR ANZ530-
531-535-538-539-542.
SMALL CRAFT ADVISORY FROM 6 AM SUNDAY TO 5 AM EST MONDAY FOR
ANZ532>534-537-540-541-543.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EST SUNDAY FOR ANZ536.
&&
$$
SYNOPSIS...JRK
NEAR TERM...JRK/KCS
SHORT TERM...HAS
LONG TERM...CEB
AVIATION...JRK/HAS/KCS/CEB
MARINE...JRK/HAS/KCS/CEB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
631 PM EST SAT JAN 18 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 446 PM EST SAT JAN 18 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW VERY FAMILIAR UPR
AIR PATTERN WITH DEEP TROF OVER CENTRAL/ERN NAMERICA DOWNSTREAM OF
HI AMPLITUDE RDG OVER THE W. ALTHOUGH SOME LO CLDS/LGT SHSN OR
FLURRIES WERE ARND INTO EARLY AFTN WITH LLVL MSTR TRAPPED UNDER LO
INVRN SHOWN ON THE 12Z INL/GRB RAOBS...ARRIVAL OF DRIER LLVL AIR
DEPICTED ON THE INL RAOB HAS TENDED TO DIMINISH THIS LO CLD.
OTRW...THERE IS RELATIVELY QUIET WX OVER UPR MI TDAY GIVEN SHRTWV
RDG/MID LVL DRY AIR SHOWN ON THE RAOBS DOMINATING THE UPR LKS TO THE
N OF POTENT CLIPPER SHRTWV DIGGING SEWD THRU THE MIDWEST. NEXT
DISTURBANCE IN THE NEVER ENDING PARADE OF CLIPPER SHRTWVS IS NOW
DIGGING SSEWD THRU NRN MANITOBA AND INTO FAR NW ONTARIO. FAIRLY
SHARP PRES FALLS AND EXTENSIVE CLD COVER ARE EVIDENT IN MANITOBA AND
NW ONTARIO AHEAD OF THIS SHRTWV.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE IMPACT ON POPS/WINDS/
BLSN OF SHRTWV DIGGING SEWD INTO NW ONTARIO AND TEMPS TRENDS TNGT.
TNGT...SHRTWV/ACCOMPANYING SFC LO OVER NW ONTARIO THIS EVNG ARE
PROGGED TO MOVE TO NEAR JAMES BAY BY 12Z SUN...WITH ATTENDANT COLD
FNT REACHING THE KEWEENAW TOWARD 12Z. MODELS INDICATE THE SFC LO WL
DEEPEN FM ABOUT 995MB THIS EVNG TO 985MB ON SUN MRNG AS THE SHRTWV
DIGS INTO THE MEAN UPR TROF. ALTHOUGH BULK OF THE ACCOMPANYING
DPVA/DEEP LYR QVECTOR CNVGC ARE PROGGED TO SWING THRU ONTARIO AND N
OF THE CWA IN THE 06Z-12Z TIME FRAME...SOME OF THIS FORCING DOES
IMPACT UPR MI. MODELS INDICATE FAIRLY DEEP MOISTENING...WHICH IS
BACKED UP BY COLDER CLD TOPS AND UPSTREAM OBS IN NRN MANITOBA AND
SASKATCHEWAN SHOWING FAIRLY WDSPRD LGT SN EVEN ON THE ACYC SIDE OF
SHRTWV TRACK. GIVEN THESE OBS...SUSPECT THE HIER QPF UP TO 0.20 INCH
OVER THE W THRU 12Z SUN SHOWN BY THE 12Z NAM/REGIONAL GEM MAY BE ON
THE RIGHT TRACK DESPITE MARGINAL H85 TEMPS FOR LES. STRENGTHENING
UPSLOPE W-SW FLOW WOULD ALSO TEND TO ENHANCE PCPN TOTALS IN THIS
AREA. THE COMBINATION OF THE FALLING SN AND GUSTY WINDS OVER THE
MORE EXPOSED KEWEENAW PENINSULA ACCENTUATED BY H925 WINDS UP TO
35-40 KTS WL LIKELY CAUSE BLSN/SHARPLY REDUCED VSBY. PLAN TO REISSUE
SPS FOR THIS AREA. DOWNSLOPE NATURE OF WSW FLOW WL TEND TO LIMIT QPF
OVER THE CNTRL ZNS. AS FOR TEMPS...READINGS MAY FALL OFF FAIRLY
QUICKLY EARLY UNDER CLR-PCLDY SKIES...BUT COMBINATION OF INCRSG
CLDS/WINDS BY LATE EVNG SHOULD CAUSE TEMPS TO REBOUND...ESPECIALLY
IN THE DOWNSLOPE AREAS NEAR LK SUP.
SUN...AS SHRTWV/SFC LO MOVE INTO QUEBEC...ATTENDANT COLD FNT WL
CROSS UPR MI...CLRG MENOMINEE ARND 18Z. THERE MAY BE A PERIOD OF
HEAVIER SHSN/BLSN NEAR LK SUP E OF MQT ACCOMPANYING THE FROPA WITH
WSHFT TO THE NW AND GUSTY WINDS/H925 WINDS STILL NEAR 30 KTS. OPTED
TO INCLUDE THIS AREA IN SPS ISSUED FOR THE NW CWA TNGT. ALTHOUGH
FCST NNW FLOW IN THE WAKE OF THIS FROPA AND H85 TEMPS FALLING TO
ARND -20C OVER THE NRN TIER BY 00Z MON WL BE FVRBL FOR LES IN THE
FAVORED SN BELTS...DEEP LYR QVECTOR DVGC/SUBSIDENCE IN THE WAKE OF
SHRTWV PASSAGE THAT IS FCST TO SHARPEN INVRN ARND 3K FT WL TEND TO
LIMIT THE INTENSITY OF THE LES...ESPECIALLY OVER THE W DOWNWIND OF
MORE ICE BUILDUP OVER WRN LK SUP. EXPECT LESS BLSN IN THE AFTN GIVEN
TREND FOR DIMINISHING WINDS WITH CLOSER APRCH OF ARCTIC HI PRES.
ALTHOUGH ANOTHER CLIPPER SHRTWV IS FCST TO MOVE INTO NRN MN LATER IN
THE DAY WITH SOME DPVA/DEEP LYR QVECTOR CNVGC IMPACTING UPR
MI...FCST SDNGS HINT THERE WL BE TOO MUCH DRYING IN THE WAKE OF
STRONGER QUEBEC CLIPPER TO ALLOW FOR MUCH MORE THAN BKN CLDS AWAY FM
THE LES AREAS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 446 PM EST SAT JAN 18 2014
A SERIES OF CLIPPERS AND ARCTIC AIR WILL DOMINATE THE LONG TERM
PATTERN AS DEEP TROUGHING ACROSS EASTERN CANADA GENERALLY REMAINS IN
PLACE.
SUNDAY NIGHT THROUGH TUESDAY...A MID-LEVEL LOW IN THE VICINITY OF
JAMES BAY WILL SLOWLY DRIFT EASTWARD ACROSS NORTHERN QUEBEC THROUGH
THE BEGINNING OF THE PERIOD...SENDING A SERIES OF TROUGHS
SOUTHEASTWARD ACROSS UPPER MI. THE FIRST OF THESE WILL CROSS THE
AREA LATE SUNDAY NIGHT IN ASSOCIATION WITH THE CONTINUED ADVECTION
OF ARCTIC AIR ACROSS THE REGION. AN UPTICK IN LES FOR THE N TO NNW
SNOW BELTS IS EXPECTED WITH THE TROUGH PASSAGE AS LAKE EQUILIBRIUM
VALUES SURPASS 9KFT OVER EASTERN LAKE SUPERIOR. HI-RES MODEL
GUIDANCE AND EVEN SOME MEDIUM-RES GUIDANCE IS ALSO STARTING TO
INDICATE A LAKE-INDUCED SFC TROUGH/EASTERLY LAND BREEZE CONV ZONE
NORTH OF GRAND MARAIS. THE LAKE-ICE COVER IS BECOMING MORE
WIDESPREAD OVER FAR EASTERN LAKE SUPERIOR...AND WHITEFISH BAY IS
COMPLETELY FROZEN OVER PER TODAYS SATELLITE IMAGERY. THIS HAS
ALLOWED THE LAND BREEZE CONV ZONE TO SET UP FARTHER WEST TODAY...AND
WOULD EXPECT SIMILAR BEHAVIOR FOR SUNDAY NIGHT...ESPECIALLY WITH
QUITE COLD AIR FLOWING OFF ONTARIO. LITTLE SHOULD CHANGE THROUGH
MONDAY NIGHT AS PERSISTENT NNW FLOW CONTINUES TO BRING ARCTIC AIR
ACROSS THE AREA. SNOWFALL AMOUNTS ARE A LITTLE TRICKY AS THE ARCTIC
AIR TENDS TO MAKE SLR VALUES LOWER. HOWEVER...FROM EXPERIENCE SO FAR
THIS SEASON...THE EXTENDED FETCH FOR THE EASTERN CWA MAY ALLOW FOR
MORE MODERATION OF THE ARCTIC AIR...RESULTING IN A DEEPER FAVORABLE
SNOW GROWTH LAYER. HAVE THUS INCREASED RATIOS A BIT ACROSS THE EAST
WHILE LOWERED THEM ELSEWHERE. ALSO...POROUS ICE COVER DEVELOPING
ACROSS WESTERN LAKE SUPERIOR MAY LIMIT LES TO SOME
DEGREE...ESPECIALLY LOCATIONS DOWNWIND OF ISLE ROYALE. OVERALL...NOT
ANTICIPATING ANY EXTREME SNOWFALL UNLESS A CONVERGENT BAND REMAINS
ANCHORED OVER A GIVEN LOCATION...MOST LIKELY BETWEEN MUNISING AND
GRAND MARAIS...FOR AN EXTENDED PERIOD OF TIME. LOW-END ADVISORY
AMOUNTS ARE POSSIBLE SUNDAY NIGHT THROUGH MONDAY WITH GENERALLY 3 TO
6 INCHES...THOUGH LOCAL AMOUNTS OF 8 INCHES ARE POSSIBLE. THE
NORTHERN EXTENT OF A WEAK SFC RIDGE WILL BACK WINDS ON TUESDAY AND
PUSH LES ACTIVITY OFF SHORE FOR MOST LOCATIONS.
A CONTINUOUS INFLUX OF H8 TEMPS AROUND -25C WILL BE PRESENT MONDAY
THROUGH TUESDAY AND BRING RATHER COLD CONDITIONS ACROSS THE AREA.
HOWEVER...TEMPS SHOULD REMAIN WARMER THAN WAS SEEN EARLIER IN THE
MONTH. ADDITIONALLY...WINDS WILL REMAIN MUCH LIGHTER EXCEPT ALONG
THE WARMER LAKE SHORES. STILL...WITH TEMPS FALLING TO THE TEENS
BELOW ZERO MONDAY NIGHT FOR THE INTERIOR WEST AND CENTRAL...A WIND
CHILL ADVISORY MAY BE NEEDED WITH CHILLS DOWN TO -30F.
WEDNESDAY INTO SATURDAY...YET ANOTHER POTENT CLIPPER WILL PUSH
SOUTHEAST RIGHT OVER THE CWA WEDNESDAY MORNING INTO THE AFTERNOON. A
QUICK ROUND OF MODERATE SNOW IS POSSIBLE FOR MUCH OF THE CWA
WEDNESDAY MORNING WITH IMPRESSIVE Q-VECTOR CONVERGENCE AND UPPER PV
ANOMALY. THE GFS HAS BEEN THE OUTLIER WITH THIS SYSTEM...SO HAVE
TRENDED WITH THE ECMWF AND GEM. BEHIND THE SYSTEM...INCREASING N TO
NE GRADIENT FLOW BETWEEN A LAGGING 1020 MB LAKE-INDUCED TROUGH AND
IMPINGING 1044 MB HIGH WILL BRING A POSSIBLY INTENSE BOUT OF LAKE
ENHANCED SNOW TO NORTH-CENTRAL UPPER MI. HAVE BUMPED UP POPS
CONSIDERABLY...AND LATER SHIFTS WILL NEED TO MONITOR MODEL TRENDS AS
HEADLINES WILL BE POSSIBLE WEDNESDAY AFTERNOON AND EVENING ALONG
LAKE SUPERIOR.
TEMPS CONTINUE TO REMAIN WELL BELOW NORMAL INTO THURSDAY AFTER
ANOTHER SHOT OF -25C H8 TEMPS WEDNESDAY AFTERNOON. DID NOT DEVOTE
MUCH TIME TO THE FORECAST BEYOND WEDNESDAY GIVEN MODEL DISAGREEMENT
AT THIS TIME...THOUGH WEIGHTED THE FORECAST TOWARD THE MORE
CONSISTENT ECMWF. INDICATIONS ARE THAT ANOTHER POTENT TROUGH AND
ACTIVE FEW DAYS OF WX WILL AFFECT THE AREA FRIDAY INTO SATURDAY
MORNING...WITH PERSISTENT LES FOR WNW SNOW BELTS THROUGH THE WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 629 PM EST SAT JAN 18 2014
INITIALLY...DRY AIR MASS WILL ENSURE VFR CONDITIONS PREVAIL AT
KIWD/KCMX/KSAW THIS EVENING. THEN...DEEPENING SFC LOW PRES MOVING
ACROSS NRN ONTARIO WILL SEND ASSOCIATED COLD FRONT S INTO THE UPPER
LAKES. TIGHTENING PRES GRADIENT WILL RESULT IN INCREASING W TO SW
WINDS LATE EVENING AND OVERNIGHT AHEAD OF FRONT. SNOW WILL ALSO
DEVELOP NEAR/SHORTLY AFTER MIDNIGHT AT KIWD/KCMX. COMBINATION OF
FALLING AND BLSN WHIPPED UP BY THE GUSTY WINDS WILL LEAD TO IFR VIS
KIWD AND LIFR VIS AT THE MORE EXPOSED KCMX LOCATION. DOWNSLOPE
NATURE OF THE EXPECTED WSW FLOW WILL LIKELY MAINTAIN VFR WX AT KSAW
EVEN AFTER -SN BEGINS. STRONG SUBSIDENCE AND DIMINISHING WINDS IN
THE WAKE OF COLD FROPA SUN MORNING SHOULD LIMIT THE INTENSITY OF
LAKE EFFECT SNOW/BLSN...BUT IFR VIS IS LIKELY TO PERSIST THRU THE
MORNING AT KCMX BEFORE IMPROVEMENT TO MVFR IN THE AFTN. WSHFT TO A
MORE UPSLOPE NNW DIRECTION WILL LEAD TO DEVELOPMENT OF MVFR
CONDITIONS AT KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 446 PM EST SAT JAN 18 2014
RELATIVELY LIGHT WINDS EARLY THIS EVENING WILL GIVE WAY TO A WSW
GALE OVER MUCH OF CENTRAL AND EASTERN LAKE SUPERIOR OVERNIGHT AS THE
PRES GRADIENT TIGHTENS OVER THE UPPER LAKES S OF DEEPENING LO PRES
CROSSING ONTARIO. THE GALES WILL VEER TO THE NW ON SUN MORNING
FOLLOWING A COLD FRONTAL PASSAGE...BUT THE WINDS WILL TEND TO
DIMINISH TO 25-30 KTS DURING THE AFTERNOON WITH ARRIVAL OF WEAKER
PRES GRADIENT AHEAD OF APPROACHING HI PRES IN THE NORTHERN PLAINS.
DESPITE THE WEAKENING WINDS...ARRIVAL OF VERY COLD ARCTIC AIRMASS
WILL RESULT IN SOME HEAVY FREEZING SPRAY IN THE AFTERNOON OVER ABOUT
THE E HALF...SO STARTED THE HEAVY FREEZING SPRAY WARNING FOR THIS
AREA AT 18Z SUN. GOING GALE HEADLINE LOOKS TO BE IN GOOD SHAPE.
PERSISTENT NW FLOW OF 20 TO 30 KNOTS WILL CONTINUE THROUGH MONDAY
NIGHT BEFORE WINDS BACK AND WEAKEN IN RESPONSE TO THE NORTHERN
EXTENT OF A SFC RIDGE TUESDAY INTO TUESDAY NIGHT. A POTENT SYSTEM
TRACKING SE OVER UPPER MI WEDNESDAY MAY BRING N TO NE GALES ACROSS
MUCH OF THE LAKE WEDNESDAY AFTERNOON AND NIGHT. ANOTHER WEAK RIDGE
WILL DIMINISH AND BACK WINDS TO THE SW ON THURSDAY. THEN...SW GALES
TO 35 KNOTS WILL BE POSSIBLE THURSDAY NIGHT INTO FRIDAY AHEAD OF
ANOTHER STRONG TROUGH ACROSS SOUTH CENTRAL CANADA. 20 TO 30 KNOTS
WILL CONTINUE THROUGH SATURDAY WHILE VEERING TO THE NW.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 1 PM SUNDAY TO 7 AM EST
TUESDAY FOR LSZ251-267.
GALE WARNING FROM 11 PM THIS EVENING TO 4 PM EST SUNDAY FOR
LSZ249>251-266-267.
HEAVY FREEZING SPRAY WARNING FROM 1 PM SUNDAY TO 7 PM EST
TUESDAY FOR LSZ249-250-266.
HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 1 PM EST
TUESDAY FOR LSZ244-245-248-264-265.
GALE WARNING FROM 11 PM THIS EVENING TO 7 AM EST SUNDAY FOR
LSZ265.
GALE WARNING UNTIL 7 AM EST SUNDAY FOR LSZ242>245-263-264.
HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 7 AM EST
TUESDAY FOR LSZ243-263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KLUBER
AVIATION...ROLFSON
MARINE...KC/KLUBER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1248 PM EST FRI JAN 17 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 533 AM EST FRI JAN 17 2014
NO CHANGES TO TIMING OF LAKE EFFECT SNOW ADVISORIES ALONG LAKE
SUPERIOR TO THE EAST OF GRAND MARAIS FOR LAKE ENHANCED SNOW AND
BLOWING/DRIFTING SNOW.
SFC LOW IS OVER NORTHERN LAKE MICHIGAN AS OF 10Z. TROUGH EXTENDS
BACK INTO NCNTRL UPR MICHIGAN. WIND SHIFT IS PRESSING SOUTH BTWN BIG
BAY AND MARQUETTE. THUS FAR OVERNIGHT...SNOW AMOUNTS HAVE BEEN IN
THE 3 TO 6 INCH RANGE OVER WEST AND NORTHWEST UPR MICHIGAN. THE MOST
SNOW HAS OCCURRED VCNTY OF IRONWOOD AND BERGLAND. ALSO SAW A BURST
OF HEAVIER SNOW MAKE IT AS FAR SOUTH AS SOUTHERN DELTA COUNTY. RADAR
ALGORITM INDICATED 2 TO 3 INCHES OVERNIGHT IN THE RAPID RIVER AREA.
APPEARS THAT THIS BURST OF SNOW WELL AWAY FM LK SUPERIOR IS SETTLING
DOWN NOW. FINALLY...ANOTHER BIG ISSUE OVER THE WEST AND NORTHWEST
CWA IS BLSN/DRSN THAT IS REDUCING VSBY...ESPECIALLY IN OPEN AREAS
NEAR LAKE SUPERIOR...WHERE KEWEENAW COUNTY SHERIFF REPORTED HEAVY
BLOWING AND DRIFTING SNOW WAS OCCURRING.
WV LOOP SHOWING THAT A SHORTWAVE IS ENHANCING OVER CNTRL UPR
MICHIGAN/SCNTRL LK SUPERIOR SINCE MIDNIGHT. RADAR REFLECTIVITIES
HAVE SHOWN THIS AS WELL WITH MORE 25+ DBZ ECHOES APPEARING OVER
NORTHERN MARQUETTE COUNTY IN THE LAST FEW HOURS. EXPECT AFFECTS OF
SHORTWAVE TO FINISH UP IN THE NEXT FEW HOURS OVER WESTERN CWA WITH
ENHANCEMENT TAPERING OFF THERE. ENHANCEMENT LIKELY WILL LAST WELL
INTO THE MORNING FOR NCNTRL UPR MICHIGAN THOUGH. SNOW AMOUNTS WILL
BE SUPPORTED FURTHER BY STRONGER LOW-LEVEL CONVERGENCE...AFFECTING
NORTHERN MARQUETTE COUNTY INTO WESTERN ALGER COUNTY AS NORTH WINDS
OVER LK SUPERIOR CONVERGE WITH NW WINDS OVER THE LAND AREAS. SNOW
AMOUNTS THROUGH THE DAY SHOULD MAXIMIZE OUT OVER NORTHERN AND
EASTERN MARQUETTE COUNTY...WITH ADDITIONAL SNOWFALL OF 3 TO 6 INCHES
LIKELY OVER PRETTY WIDE AREA. A BIT CONCERNED MAY NEED A WARNING AS
WINDS JUST OFF SFC ARE MAINLY NORTHEAST AND MODELS ARE NOT PICKING
UP ON THAT. ONLY RUC13 SHOWS THIS...BUT NOT UNTIL 14Z. NOT SURE IF
THIS IS SITUATION THAT MODELS ARE TOO SLOW OR FAVORABLE NE UPSLOPE
WILL PERSIST WELL INTO THE DAY. IF IT DOES...SNOW AMOUNTS WILL BE
PUSHING THE 8 INCH/12 HR CRITERIA. BLSN/DRSN ISSUES WILL ALSO
INCREASE AS NORTH WINDS GUST OVER 30 MPH. OPEN AREAS AND AREAS ALONG
LK SUPERIOR WILL BE MOST VULNERABLE TO POOR VSBY. COORIDORS OF SUB
QUARTER MILE VSBY SEEM LIKELY IN THE HEAVIER SNOW AREAS THIS
MORNING. WILL NEED TO WATCH THIS AS WELL. EVENTUALLY AS SHORTWAVE
DROPS MORE ESE...HEAVIER SNOW SHOWERS AND BLSN/DRSN ISSUES WILL
BEGIN TO AFFECT WESTERN ALGER COUNTY. CONTINUED TO HIGHLIGHT
POTENTIAL FOR DIFFICULT TRAVEL ON M-28 LATER THIS MORNING WITH
SNOW/BLSN/DRSN.
ONCE THE SHORTWAVE AND LARGER SCALE TROUGHING SLIDE MAINLY EAST OF
CWA BY LATE THIS AFTN...EXPECT WEATHER TO QUIET DOWN. SOUNDINGS FOR
THIS EVENING EVEN WHERE FLOW BLO 5KFT REMAINS ONSHORE LOOKING MORE
AND MORE HOSTILE FOR NOTHING MORE THAN LGT LAKE EFFECT OR FLURRIES.
KEPT POPS HIGH IN THE SNOWBELTS EAST OF MARQUETTE BUT SNOW AMOUNTS
LOOK MINIMAL. OVER WEST HALF OF UPR MICHIGAN...EXPECT CLEARING SKIES
FOR GOOD PART OF NIGHT UNTIL HIGH CLOUDS INCREASE LATE AHEAD OF
SYSTEM DIGGING DOWN INTO THE NORTHERN PLAINS. SYSTEM HAS TRENDED
FARTHER WEST...SO IMPACTS FM THE CLOUDS MAY END UP BEING LESS AND
LESS. KEPT WITH THEME OF SUB ZERO TEMPS FOR MUCH OF WEST HALF
INTERIOR. THESE TEMPS MAY NEED FURTHER LOWERING IF CLOUDS DO NOT COME
IN AT ALL LATER TONIGHT AS WINDS WILL BE LIGHT AND RADITIONAL COOLING
WILL BE IDEAL.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 436 AM EST FRI JAN 17 2014
NAM SHOWS A 500 MB TROUGH OVER THE GREAT LAKES REGION 12Z SAT WITH A
SHORTWAVE OVER MN. THIS SHORTWAVE DIGS SOUTHEAST INTO ILLINOIS BY
00Z SUN AND LOOKS LIKE IT WILL STAY TO THE WEST OF THE AREA. NAM
BRINGS IN ANOTHER SHORTWAVE THAT WILL AFFECT THE AREA SUN NIGHT.
WITH FIRST SHORTWAVE AND COLD AIR GOING TO THE WEST OF THE
AREA...CUT BACK ON EASTWARD EXTENT OF POPS ON SAT. WITH LESS
COVER...MORE SUNSHINE WILL OCCUR WITH SW WINDS AND WENT A BIT HIGHER
FOR TEMPERATURES. COLD AIR COMES IN SAT NIGHT INTO SUNDAY WITH
TEMPERATURES NOT GOING UP MUCH ON SUNDAY. WENT HIGHEST POPS IN NW
LAKE EFFECT SNOW BELTS. OTHERWISE...NOT MANY CHANGES TO THE GOING
FORECAST.
IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH OVER THE
CENTRAL U.S. 12Z MON WITH VERY COLD AIR OVER THE AREA AGAIN WITH 850
MB TEMPERATURES DOWN TO -25C OR SO. THIS TROUGH DIGS OVER THE LOWER
GREAT LAKES 12Z TUE AND THE TROUGH CONTINUES WITH THE COLD AIR 12Z
WED WITH THE TROUGH AXIS OVER NEW ENGLAND ON THU. TEMPERATURES WILL
REMAIN BELOW NORMAL THIS FORECAST PERIOD WITH LAKE EFFECT SNOW
CONTINUING THROUGH WED NIGHT. WITH NORTHERLY WINDS...WENT HIGH POPS
IN NORTHERLY AFFECTED LAKE EFFECT SNOW BELTS. DID NOT MAKE TOO MANY
CHANGES TO THE GOING FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1246 PM EST FRI JAN 17 2014
RESIDUAL LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO DIMINISH THROUGH
THE AFTERNOON AND EARLY EVENING FOR ALL THREE SITES. AN APPROACHING
SFC RIDGE FROM THE WEST WILL BACK WINDS AND PUSH ANY REMAINING -SHSN
AND LOW-END MVFR CLOUDS AWAY FROM IWD BY EARLY EVENING...AND CMX AND
SAW OVERNIGHT. HELD ONTO THE LOWER CIGS AND -SHSN AT CMX AND SAW
WELL INTO THE OVERNIGHT HOURS AS WINDS WILL TAKE A WHILE TO BACK
ENOUGH TO REMOVE UPSLOPE INFLUENCE. AS THE SFC RIDGE CROSSES THE
AREA OVERNIGHT...EXPECT LIGHT AND VARIABLE WINDS FOR ALL SITES. VFR
CONDITIONS WILL PERSIST THROUGH MUCH OF SATURDAY...THOUGH MID-LEVEL
CLOUDS ABOVE 5KFT MAY BRUSH IWD SATURDAY MORNING AS LOW PRESSURE
PASSES TO THE SOUTHWEST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 436 AM EST FRI JAN 17 2014
GALES OVER CENTRAL LAKE SUPERIOR WILL CONTINUE TO WIND DOWN TODAY.
NEXT GALE EVENT LOOKS TO BE SAT NIGHT INTO SUNDAY ACROSS THE EAST
HALF OF LAKE SUPERIOR WITH COLD AIR MOVING ACROSS LAKE SUPERIOR
AGAIN. HEAVY FREEZING SPRAY WILL LAST INTO THIS EVENING ACROSS LAKE
SUPERIOR BEFORE WINDS DIE DOWN ENOUGH TO STOP CAUSING IT. HEAVY
FREEZING SPRAY WILL AGAIN OCCUR SUNDAY INTO TUE SINCE THE INCOMING
AIRMASS WILL BE QUITE COLD. THERE WILL BE SOME HEAVY FREEZING SPRAY
WHERE WAVE ACTION IS HIGHEST.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR
MIZ006.
LAKE EFFECT SNOW ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MIZ013.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ005.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL MIDNIGHT EST TONIGHT FOR
LSZ245-248-249-265-266.
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR LSZ162.
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST THIS EVENING FOR
LSZ244-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...07
AVIATION...KLUBER
MARINE...07
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
702 AM EST FRI JAN 17 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 533 AM EST FRI JAN 17 2014
NO CHANGES TO TIMING OF LAKE EFFECT SNOW ADVISORIES ALONG LAKE
SUPERIOR TO THE EAST OF GRAND MARAIS FOR LAKE ENHANCED SNOW AND
BLOWING/DRIFTING SNOW.
SFC LOW IS OVER NORTHERN LAKE MICHIGAN AS OF 10Z. TROUGH EXTENDS
BACK INTO NCNTRL UPR MICHIGAN. WIND SHIFT IS PRESSING SOUTH BTWN BIG
BAY AND MARQUETTE. THUS FAR OVERNIGHT...SNOW AMOUNTS HAVE BEEN IN
THE 3 TO 6 INCH RANGE OVER WEST AND NORTHWEST UPR MICHIGAN. THE MOST
SNOW HAS OCCURRED VCNTY OF IRONWOOD AND BERGLAND. ALSO SAW A BURST
OF HEAVIER SNOW MAKE IT AS FAR SOUTH AS SOUTHERN DELTA COUNTY. RADAR
ALGORITM INDICATED 2 TO 3 INCHES OVERNIGHT IN THE RAPID RIVER AREA.
APPEARS THAT THIS BURST OF SNOW WELL AWAY FM LK SUPERIOR IS SETTLING
DOWN NOW. FINALLY...ANOTHER BIG ISSUE OVER THE WEST AND NORTHWEST
CWA IS BLSN/DRSN THAT IS REDUCING VSBY...ESPECIALLY IN OPEN AREAS
NEAR LAKE SUPERIOR...WHERE KEWEENAW COUNTY SHERIFF REPORTED HEAVY
BLOWING AND DRIFTING SNOW WAS OCCURRING.
WV LOOP SHOWING THAT A SHORTWAVE IS ENHANCING OVER CNTRL UPR
MICHIGAN/SCNTRL LK SUPERIOR SINCE MIDNIGHT. RADAR REFLECTIVITIES
HAVE SHOWN THIS AS WELL WITH MORE 25+ DBZ ECHOES APPEARING OVER
NORTHERN MARQUETTE COUNTY IN THE LAST FEW HOURS. EXPECT AFFECTS OF
SHORTWAVE TO FINISH UP IN THE NEXT FEW HOURS OVER WESTERN CWA WITH
ENHANCEMENT TAPERING OFF THERE. ENHANCEMENT LIKELY WILL LAST WELL
INTO THE MORNING FOR NCNTRL UPR MICHIGAN THOUGH. SNOW AMOUNTS WILL
BE SUPPORTED FURTHER BY STRONGER LOW-LEVEL CONVERGENCE...AFFECTING
NORTHERN MARQUETTE COUNTY INTO WESTERN ALGER COUNTY AS NORTH WINDS
OVER LK SUPERIOR CONVERGE WITH NW WINDS OVER THE LAND AREAS. SNOW
AMOUNTS THROUGH THE DAY SHOULD MAXIMIZE OUT OVER NORTHERN AND
EASTERN MARQUETTE COUNTY...WITH ADDITIONAL SNOWFALL OF 3 TO 6 INCHES
LIKELY OVER PRETTY WIDE AREA. A BIT CONCERNED MAY NEED A WARNING AS
WINDS JUST OFF SFC ARE MAINLY NORTHEAST AND MODELS ARE NOT PICKING
UP ON THAT. ONLY RUC13 SHOWS THIS...BUT NOT UNTIL 14Z. NOT SURE IF
THIS IS SITUATION THAT MODELS ARE TOO SLOW OR FAVORABLE NE UPSLOPE
WILL PERSIST WELL INTO THE DAY. IF IT DOES...SNOW AMOUNTS WILL BE
PUSHING THE 8 INCH/12 HR CRITERIA. BLSN/DRSN ISSUES WILL ALSO
INCREASE AS NORTH WINDS GUST OVER 30 MPH. OPEN AREAS AND AREAS ALONG
LK SUPERIOR WILL BE MOST VULNERABLE TO POOR VSBY. COORIDORS OF SUB
QUARTER MILE VSBY SEEM LIKELY IN THE HEAVIER SNOW AREAS THIS
MORNING. WILL NEED TO WATCH THIS AS WELL. EVENTUALLY AS SHORTWAVE
DROPS MORE ESE...HEAVIER SNOW SHOWERS AND BLSN/DRSN ISSUES WILL
BEGIN TO AFFECT WESTERN ALGER COUNTY. CONTINUED TO HIGHLIGHT
POTENTIAL FOR DIFFICULT TRAVEL ON M-28 LATER THIS MORNING WITH
SNOW/BLSN/DRSN.
ONCE THE SHORTWAVE AND LARGER SCALE TROUGHING SLIDE MAINLY EAST OF
CWA BY LATE THIS AFTN...EXPECT WEATHER TO QUIET DOWN. SOUNDINGS FOR
THIS EVENING EVEN WHERE FLOW BLO 5KFT REMAINS ONSHORE LOOKING MORE
AND MORE HOSTILE FOR NOTHING MORE THAN LGT LAKE EFFECT OR FLURRIES.
KEPT POPS HIGH IN THE SNOWBELTS EAST OF MARQUETTE BUT SNOW AMOUNTS
LOOK MINIMAL. OVER WEST HALF OF UPR MICHIGAN...EXPECT CLEARING SKIES
FOR GOOD PART OF NIGHT UNTIL HIGH CLOUDS INCREASE LATE AHEAD OF
SYSTEM DIGGING DOWN INTO THE NORTHERN PLAINS. SYSTEM HAS TRENDED
FARTHER WEST...SO IMPACTS FM THE CLOUDS MAY END UP BEING LESS AND
LESS. KEPT WITH THEME OF SUB ZERO TEMPS FOR MUCH OF WEST HALF
INTERIOR. THESE TEMPS MAY NEED FURTHER LOWERING IF CLOUDS DO NOT COME
IN AT ALL LATER TONIGHT AS WINDS WILL BE LIGHT AND RADITIONAL COOLING
WILL BE IDEAL.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 436 AM EST FRI JAN 17 2014
NAM SHOWS A 500 MB TROUGH OVER THE GREAT LAKES REGION 12Z SAT WITH A
SHORTWAVE OVER MN. THIS SHORTWAVE DIGS SOUTHEAST INTO ILLINOIS BY
00Z SUN AND LOOKS LIKE IT WILL STAY TO THE WEST OF THE AREA. NAM
BRINGS IN ANOTHER SHORTWAVE THAT WILL AFFECT THE AREA SUN NIGHT.
WITH FIRST SHORTWAVE AND COLD AIR GOING TO THE WEST OF THE
AREA...CUT BACK ON EASTWARD EXTENT OF POPS ON SAT. WITH LESS
COVER...MORE SUNSHINE WILL OCCUR WITH SW WINDS AND WENT A BIT HIGHER
FOR TEMPERATURES. COLD AIR COMES IN SAT NIGHT INTO SUNDAY WITH
TEMPERATURES NOT GOING UP MUCH ON SUNDAY. WENT HIGHEST POPS IN NW
LAKE EFFECT SNOW BELTS. OTHERWISE...NOT MANY CHANGES TO THE GOING
FORECAST.
IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH OVER THE
CENTRAL U.S. 12Z MON WITH VERY COLD AIR OVER THE AREA AGAIN WITH 850
MB TEMPERATURES DOWN TO -25C OR SO. THIS TROUGH DIGS OVER THE LOWER
GREAT LAKES 12Z TUE AND THE TROUGH CONTINUES WITH THE COLD AIR 12Z
WED WITH THE TROUGH AXIS OVER NEW ENGLAND ON THU. TEMPERATURES WILL
REMAIN BELOW NORMAL THIS FORECAST PERIOD WITH LAKE EFFECT SNOW
CONTINUING THROUGH WED NIGHT. WITH NORTHERLY WINDS...WENT HIGH POPS
IN NORTHERLY AFFECTED LAKE EFFECT SNOW BELTS. DID NOT MAKE TOO MANY
CHANGES TO THE GOING FORECAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 701 AM EST FRI JAN 17 2014
LAKE ENHANCED SNOW AND BLOWING SNOW WILL BRING IFR CONDITIONS TO
KIWD AND KCMX EARLY...BUT EXPECT IMPROVEMENT TO MVFR THIS AFTERNOON.
AS WINDS BACK W TO SW WITH ARRIVAL OF SFC HIGH PRES RIDGE...MVFR
CIGS WILL CLEAR OUT AT KIWD EARLY THIS EVENING AND OVERNIGHT AT
KCMX. AT KSAW...PASSAGE OF SFC TROF EARLY THIS MORNING WILL BRING
HEAVIER SHSN/BLSN AND IFR CONDITIONS. NOT OUT OF THE QUESTION THAT A
FEW PERIODS OF LIFR COULD OCCUR THIS MORNING AND HAVE PUT A TEMPO
GROUP IN FOR THIS. EXPECT IMPROVEMENT TO MVFR THIS AFTN AS WINDS
BEGIN TO BACK NORTHWEST. MVFR CIGS WILL CLEAR OUT THIS EVENING
AT KSAW AS WINDS BACK FURTHER.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 436 AM EST FRI JAN 17 2014
GALES OVER CENTRAL LAKE SUPERIOR WILL CONTINUE TO WIND DOWN TODAY.
NEXT GALE EVENT LOOKS TO BE SAT NIGHT INTO SUNDAY ACROSS THE EAST
HALF OF LAKE SUPERIOR WITH COLD AIR MOVING ACROSS LAKE SUPERIOR
AGAIN. HEAVY FREEZING SPRAY WILL LAST INTO THIS EVENING ACROSS LAKE
SUPERIOR BEFORE WINDS DIE DOWN ENOUGH TO STOP CAUSING IT. HEAVY
FREEZING SPRAY WILL AGAIN OCCUR SUNDAY INTO TUE SINCE THE INCOMING
AIRMASS WILL BE QUITE COLD. THERE WILL BE SOME HEAVY FREEZING SPRAY
WHERE WAVE ACTION IS HIGHEST.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR
MIZ006.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST /9 AM CST/ THIS
MORNING FOR MIZ001>004-009.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ005.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL MIDNIGHT EST TONIGHT FOR
LSZ245-248-249-265-266.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LSZ245-248-249-
265-266.
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR LSZ162.
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST THIS EVENING FOR
LSZ244-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...07
AVIATION...JLA
MARINE...07
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
535 AM EST FRI JAN 17 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 533 AM EST FRI JAN 17 2014
NO CHANGES TO TIMING OF LAKE EFFECT SNOW ADVISORIES ALONG LAKE
SUPERIOR TO THE EAST OF GRAND MARAIS FOR LAKE ENHANCED SNOW AND
BLOWING/DRIFTING SNOW.
SFC LOW IS OVER NORTHERN LAKE MICHIGAN AS OF 10Z. TROUGH EXTENDS
BACK INTO NCNTRL UPR MICHIGAN. WIND SHIFT IS PRESSING SOUTH BTWN BIG
BAY AND MARQUETTE. THUS FAR OVERNIGHT...SNOW AMOUNTS HAVE BEEN IN
THE 3 TO 6 INCH RANGE OVER WEST AND NORTHWEST UPR MICHIGAN. THE MOST
SNOW HAS OCCURRED VCNTY OF IRONWOOD AND BERGLAND. ALSO SAW A BURST
OF HEAVIER SNOW MAKE IT AS FAR SOUTH AS SOUTHERN DELTA COUNTY. RADAR
ALGORITM INDICATED 2 TO 3 INCHES OVERNIGHT IN THE RAPID RIVER AREA.
APPEARS THAT THIS BURST OF SNOW WELL AWAY FM LK SUPERIOR IS SETTLING
DOWN NOW. FINALLY...ANOTHER BIG ISSUE OVER THE WEST AND NORTHWEST
CWA IS BLSN/DRSN THAT IS REDUCING VSBY...ESPECIALLY IN OPEN AREAS
NEAR LAKE SUPERIOR...WHERE KEWEENAW COUNTY SHERIFF REPORTED HEAVY
BLOWING AND DRIFTING SNOW WAS OCCURRING.
WV LOOP SHOWING THAT A SHORTWAVE IS ENHANCING OVER CNTRL UPR
MICHIGAN/SCNTRL LK SUPERIOR SINCE MIDNIGHT. RADAR REFLECTIVITIES
HAVE SHOWN THIS AS WELL WITH MORE 25+ DBZ ECHOES APPEARING OVER
NORTHERN MARQUETTE COUNTY IN THE LAST FEW HOURS. EXPECT AFFECTS OF
SHORTWAVE TO FINISH UP IN THE NEXT FEW HOURS OVER WESTERN CWA WITH
ENHANCEMENT TAPERING OFF THERE. ENHANCEMENT LIKELY WILL LAST WELL
INTO THE MORNING FOR NCNTRL UPR MICHIGAN THOUGH. SNOW AMOUNTS WILL
BE SUPPORTED FURTHER BY STRONGER LOW-LEVEL CONVERGENCE...AFFECTING
NORTHERN MARQUETTE COUNTY INTO WESTERN ALGER COUNTY AS NORTH WINDS
OVER LK SUPERIOR CONVERGE WITH NW WINDS OVER THE LAND AREAS. SNOW
AMOUNTS THROUGH THE DAY SHOULD MAXIMIZE OUT OVER NORTHERN AND
EASTERN MARQUETTE COUNTY...WITH ADDITIONAL SNOWFALL OF 3 TO 6 INCHES
LIKELY OVER PRETTY WIDE AREA. A BIT CONCERNED MAY NEED A WARNING AS
WINDS JUST OFF SFC ARE MAINLY NORTHEAST AND MODELS ARE NOT PICKING
UP ON THAT. ONLY RUC13 SHOWS THIS...BUT NOT UNTIL 14Z. NOT SURE IF
THIS IS SITUATION THAT MODELS ARE TOO SLOW OR FAVORABLE NE UPSLOPE
WILL PERSIST WELL INTO THE DAY. IF IT DOES...SNOW AMOUNTS WILL BE
PUSHING THE 8 INCH/12 HR CRITERIA. BLSN/DRSN ISSUES WILL ALSO
INCREASE AS NORTH WINDS GUST OVER 30 MPH. OPEN AREAS AND AREAS ALONG
LK SUPERIOR WILL BE MOST VULNERABLE TO POOR VSBY. COORIDORS OF SUB
QUARTER MILE VSBY SEEM LIKELY IN THE HEAVIER SNOW AREAS THIS
MORNING. WILL NEED TO WATCH THIS AS WELL. EVENTUALLY AS SHORTWAVE
DROPS MORE ESE...HEAVIER SNOW SHOWERS AND BLSN/DRSN ISSUES WILL
BEGIN TO AFFECT WESTERN ALGER COUNTY. CONTINUED TO HIGHLIGHT
POTENTIAL FOR DIFFICULT TRAVEL ON M-28 LATER THIS MORNING WITH
SNOW/BLSN/DRSN.
ONCE THE SHORTWAVE AND LARGER SCALE TROUGHING SLIDE MAINLY EAST OF
CWA BY LATE THIS AFTN...EXPECT WEATHER TO QUIET DOWN. SOUNDINGS FOR
THIS EVENING EVEN WHERE FLOW BLO 5KFT REMAINS ONSHORE LOOKING MORE
AND MORE HOSTILE FOR NOTHING MORE THAN LGT LAKE EFFECT OR FLURRIES.
KEPT POPS HIGH IN THE SNOWBELTS EAST OF MARQUETTE BUT SNOW AMOUNTS
LOOK MINIMAL. OVER WEST HALF OF UPR MICHIGAN...EXPECT CLEARING SKIES
FOR GOOD PART OF NIGHT UNTIL HIGH CLOUDS INCREASE LATE AHEAD OF
SYSTEM DIGGING DOWN INTO THE NORTHERN PLAINS. SYSTEM HAS TRENDED
FARTHER WEST...SO IMPACTS FM THE CLOUDS MAY END UP BEING LESS AND
LESS. KEPT WITH THEME OF SUB ZERO TEMPS FOR MUCH OF WEST HALF
INTERIOR. THESE TEMPS MAY NEED FURTHER LOWERING IF CLOUDS DO NOT COME
IN AT ALL LATER TONIGHT AS WINDS WILL BE LIGHT AND RADITIONAL COOLING
WILL BE IDEAL.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 436 AM EST FRI JAN 17 2014
NAM SHOWS A 500 MB TROUGH OVER THE GREAT LAKES REGION 12Z SAT WITH A
SHORTWAVE OVER MN. THIS SHORTWAVE DIGS SOUTHEAST INTO ILLINOIS BY
00Z SUN AND LOOKS LIKE IT WILL STAY TO THE WEST OF THE AREA. NAM
BRINGS IN ANOTHER SHORTWAVE THAT WILL AFFECT THE AREA SUN NIGHT.
WITH FIRST SHORTWAVE AND COLD AIR GOING TO THE WEST OF THE
AREA...CUT BACK ON EASTWARD EXTENT OF POPS ON SAT. WITH LESS
COVER...MORE SUNSHINE WILL OCCUR WITH SW WINDS AND WENT A BIT HIGHER
FOR TEMPERATURES. COLD AIR COMES IN SAT NIGHT INTO SUNDAY WITH
TEMPERATURES NOT GOING UP MUCH ON SUNDAY. WENT HIGHEST POPS IN NW
LAKE EFFECT SNOW BELTS. OTHERWISE...NOT MANY CHANGES TO THE GOING
FORECAST.
IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH OVER THE
CENTRAL U.S. 12Z MON WITH VERY COLD AIR OVER THE AREA AGAIN WITH 850
MB TEMPERATURES DOWN TO -25C OR SO. THIS TROUGH DIGS OVER THE LOWER
GREAT LAKES 12Z TUE AND THE TROUGH CONTINUES WITH THE COLD AIR 12Z
WED WITH THE TROUGH AXIS OVER NEW ENGLAND ON THU. TEMPERATURES WILL
REMAIN BELOW NORMAL THIS FORECAST PERIOD WITH LAKE EFFECT SNOW
CONTINUING THROUGH WED NIGHT. WITH NORTHERLY WINDS...WENT HIGH POPS
IN NORTHERLY AFFECTED LAKE EFFECT SNOW BELTS. DID NOT MAKE TOO MANY
CHANGES TO THE GOING FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1149 PM EST THU JAN 16 2014
SFC TROF DROPPING S ACROSS LAKE SUPERIOR/UPPER MI WILL BRING A
PERIOD OF STRONGER N TO NW WINDS OVERNIGHT INTO THE MORNING.
INITIALLY...DEEP MOISTURE/UPSLOPE FLOW SHOULD RESULT IN PREVAILING
IFR CONDITIONS AT KIWD/KCMX WITH SOME PERIODS OF LIFR AT KCMX DUE TO
STRONGER WINDS AND RESULTING BLSN. EXPECT IMPROVEMENT TO MVFR AT
KIWD/KCMX MID TO LATE MORNING. AS WINDS BACK W TO SW WITH ARRIVAL OF
SFC HIGH PRES RIDGE...MVFR CIGS WILL CLEAR OUT AT KIWD EARLY THIS
EVENING. AT KSAW...MVFR CONDITIONS SHOULD PREVAIL FOR THE OVERNIGHT.
PASSAGE OF SFC TROF TOWARD DAYBREAK WILL BRING HEAVIER SHSN/BLSN AND
IFR CONDITIONS. NOT OUT OF THE QUESTION THAT A FEW PERIODS OF LIFR
COULD OCCUR THIS MORNING. EXPECT IMPROVEMENT TO MVFR EARLY THIS AFTN
AS WINDS BEGIN TO BACK. MVFR CIGS WILL CLEAR OUT THIS EVENING AT
KSAW AS WINDS BACK FURTHER.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 436 AM EST FRI JAN 17 2014
GALES OVER CENTRAL LAKE SUPERIOR WILL CONTINUE TO WIND DOWN TODAY.
NEXT GALE EVENT LOOKS TO BE SAT NIGHT INTO SUNDAY ACROSS THE EAST
HALF OF LAKE SUPERIOR WITH COLD AIR MOVING ACROSS LAKE SUPERIOR
AGAIN. HEAVY FREEZING SPRAY WILL LAST INTO THIS EVENING ACROSS LAKE
SUPERIOR BEFORE WINDS DIE DOWN ENOUGH TO STOP CAUSING IT. HEAVY
FREEZING SPRAY WILL AGAIN OCCUR SUNDAY INTO TUE SINCE THE INCOMING
AIRMASS WILL BE QUITE COLD. THERE WILL BE SOME HEAVY FREEZING SPRAY
WHERE WAVE ACTION IS HIGHEST.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR
MIZ006.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST /9 AM CST/ THIS
MORNING FOR MIZ001>004-009.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ005.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL MIDNIGHT EST TONIGHT FOR
LSZ245-248-249-265-266.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LSZ245-248-249-
265-266.
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR LSZ162.
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST THIS EVENING FOR
LSZ244-263-264.
GALE WARNING UNTIL 7 AM EST THIS MORNING FOR LSZ243-244-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...07
AVIATION...ROLFSON
MARINE...07
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
607 PM CST SAT JAN 18 2014
.UPDATE...FOR 00Z AVIATION DISCUSSION BELOW
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 348 PM CST SAT JAN 18 2014
WEATHER HAS BEEN QUIETING DOWN QUICKLY IN THE WAKE OF THIS MORNINGS
STRONG CLIPPER. STRONG SUBSIDENCE IN THE WAKE OF THE CLIPPER HAS
HELPED CLEAR SKIES OUT...SAVE FOR A LINGERING ZONE OF FGEN AROUND H7
THAT HAS KEPT AN AREA OF CLOUDS WITH A FEW FLURRIES GOING FROM THE
TWIN CITIES BACK TOWARD EAU...THOUGH EVEN THESE CLOUDS SHOULD SLOWLY
FADE AWAY THIS AFTERNOON.
TONIGHT...WINDS WILL QUICKLY TURN TOWARD THE SW AS A MILD PACIFIC
AIRMASS QUICKLY MOVES INTO THE AREA. WAA OUT AHEAD OF THE WARM NOSE
WILL LEAD TO A BAND OF MAINLY MID LEVEL CLOUDS WORKING BACK ACROSS
THE AREA. HOWEVER...290-295K SFCS OFF THE NAM SHOWING ENOUGH
MOISTURE MAY BE PRESENT FOR ISENTROPIC LIFT IN THE FAR NE CWA TO
GENERATE SOME -SN AS THE WARMER AIRMASS MOVES IN. THIS IS SUPPORTED
BY REFLECTIVITY FORECASTS FROM THE HRRR AND OTHER HI-RES MODELS...SO
INTRODUCED SOME CHANCE POPS FOR THAT...THOUGH ONLY ONE OR TWO TENTHS
OF AN INCH OF SNOW WOULD BE LIKELY IF ANYTHING DOES FALL. THIS WAA
TONIGHT WILL RESULT IN ANOTHER NIGHT OF NON-DIURNAL TEMP
TRENDS...WITH TEMPS LIKELY ALREADY ABOVE 30 OFF THE BUFFALO RIDGE BY
SUNRISE SUNDAY...WITH MOST OF THE MN CWA INTO THE LOW/MID 20S BY THE
START OF THE DAY SUNDAY. THE WARM START MEANS THE MILD DAY STILL
LOOKS TO BE IN PLACE. FOLLOWED MORE THE GEM/ECMWF FOR HIGHS SUNDAY
WITH MOST OF THE AREA GETTING INTO THE LOW/MID 30S. IF YOU WOULD
LIKE TO AVOID THOUGHTS OF NEEDING A VACATION TO A WARMER CLIMATE...I
SUGGEST YOU STOP READING NOW...AS THESE HIGHS SUNDAY WILL NOT BE A
LASTING TREND.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 348 PM CST SAT JAN 18 2014
THE ROLLER COASTER RIDE OF TEMPERATURE TRENDS WILL CONTINUE
THROUGHOUT THE LONG TERM. AN ARCTIC FRONT WILL SAG SOUTH SUNDAY
NIGHT INTO CENTRAL MN AND WI. STEEP LAPSE RATES UP TO ABOUT 3KFT
IN STRONG CAA REGIME AND AN ISOTHERMAL MOIST TEMPERATURE PROFILE
WITHIN THE DGZ BETWEEN 3KFT TO 10KFT SHOULD PROMOTE OCCASIONAL
LIGHT SNOW DEVELOPMENT BEHIND THE FRONT UNTIL DRIER AIR WORKS IN
MONDAY AFTERNOON. BOOSTED POPS INTO THE CATEGORICAL RANGE...BUT
THIS LOOKS LIKE A HIGH CHANCE/LOW PRECIP EVENT WITH SNOWFALL
AMOUNTS REMAINING GENERALLY A HALF INCH OR LESS. THE BEST CHANCE
OF RECEIVING UP TO AN INCH WILL BE ACROSS WESTERN AND SOUTHERN MN
WHERE A VORTICITY MAX SLIDES SOUTHEAST IN ADVANCE OF THE BUILDING
SURFACE RIDGE MONDAY AFTERNOON. THIS WILL ENHANCE THE LIFT ENOUGH
TO GET A BIT MORE ROBUST SNOWFALL.
THE HIGH BUILDS INTO WESTERN MN MONDAY NIGHT. CLEARING SKIES AND
FRESH SNOWFALL WILL EASILY ALLOW FOR A STOUT INVERSION TO SET UP
WHICH SHOULD ALSO DECOUPLE THE WIND. IF THE WIND FULLY
DECOUPLES...TEMPERATURES WILL BE VERY COLD WITH WIDESPREAD 20S
BELOW ACROSS MN /EXCEPT FOR THE TWIN CITIES METRO/ AND TEENS BELOW
ACROSS WI. SOME SPOTS IN CENTRAL MN MAY DROP TO 30 BELOW AGAIN.
FORECASTING TEMPERATURES IN SUCH A SITUATION IS INHERENTLY
DIFFICULT AS LOCATIONS CAN VARY GREATLY WITH ENHANCED LOCAL
INFLUENCES. THEREFORE...CONFIDENCE IS NOT PARTICULARLY HIGH AND IT
IS IMPOSSIBLE TO CONVEY THESE HIGHLY VARIED LOCAL INFLUENCES WITH
MUCH PRECISION IN THE GRIDS. UNLIKE THE LAST COLD OUTBREAK...THE
COLDER MOS NUMBERS MAY NOT BE AS FAR OFF FROM REALITY IN THE
DECOUPLED ENVIRONMENT. TOOK A COMPROMISE OF THE MOS NUMBERS AND
THE BIAS CORRECTED MOS NUMBERS FOR TEMPS HOPING SPLITTING THE
DIFFERENCE WILL SUFFICE.
BY TUESDAY NIGHT...A WEAK DISTURBANCE WILL DROP SOUTHEAST INTO THE
GREAT LAKES. WITH IT WILL COME A NOSE OF WARMER AIR IN OVERNIGHT
AND A CHANCE OF SNOW ACROSS MUCH OF THE AREA.
THE NEXT ARCTIC FRONT WILL ARRIVE WEDNESDAY AND ANOTHER POLAR HIGH
WILL BUILD INTO THE DAKOTAS AND MINNESOTA WEDNESDAY NIGHT. IT WILL
BE A NEARLY IDENTICAL SET UP TO MONDAY NIGHT AND THE LOW TEMP GRID
IS QUITE SIMILAR AS WELL.
SOME UNCERTAINTY HAS BEEN INTRODUCED BY THE MIDDLE OF NEXT WEEK
WITH THE GFS SHOWING A MUCH MILDER SOLUTION COMPARED TO PREVIOUS
DAYS RUNS. IT SHOWS THE TROUGH BEING CONFINED TO NEW ENGLAND AND
AN EXPANSIVE ZONAL FLOW/WEAK RIDGING ACROSS THE REST OF THE CONUS.
PREFER THE MORE STABLE ECMWF SHOWING A CONTINUATION OF A SERIES OF
POLAR FRONTS THROUGH DAY 10. NOT SEEING MUCH TO INDICATE THE
CURRENT PATTERN WILL CHANGE AND GIVEN HOW LONG IT HAS PERSISTED
THIS WINTER...IT WILL TAKE QUITE A BIT MORE CONVINCING BEFORE A
CHANGE IN DIRECTION IS NECESSARY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 607 PM CST SAT JAN 18 2014
MVFR CIGS WILL SCRAPE THE NORTHERN PORTION OF THE TAF SITES THIS
EVENING...PRIMARILY AFFECTING KAXN AND KSTC...POSSIBLY EVEN KRNH
AND KSTC AROUND/AFTER MIDNIGHT...BUT MOST LIKELY STAYING NORTH OF
KMSP/KRWF. OTHERWISE..MAINLY HIGH CLOUDS ARE EXPECTED UNTIL
AROUND/AFTER 18Z SUNDAY...WHEN MVFR CLOUDS OVER NORTHERN MN WILL
SAG INTO CENTRAL MN/WI WITH THE NEXT ARCTIC BOUNDARY.
NORTH/NORTHWEST WINDS WILL BACK SLIGHTLY TO THE SOUTHWEST THIS
EVE...THEN VEER BACK TO THE NORTHWEST BETWEEN 15Z-18Z SUNDAY.
KMSP...
MAINLY HIGH CLOUDS EXPECTED THROUGH SUNDAY MORNING...ALTHOUGH SCT
MVFR LEVEL CLOUDS COULD SKIRT THE NORTHERN EDGES OF KMSP TONIGHT.
OTHERWISE...THE HIGHER CHANCE OF MVFR CIGS WILL ARRIVE AFTER 00Z
MON...WITH FLURRIES OR LIGHT SNOW APPEARING POSSIBLE AFTER 03Z
MON. WEST/SOUTHWEST WINDS TONIGHT VEER TO THE NORTHWEST BY 15Z
SUNDAY. SPEEDS AOB 10 KTS THRU PD.
/OUTLOOK FOR KMSP/
MON...CHANCE MVFR/SN THRU MORNING. WINDS N 10KTS.
TUE...VFR. CHANCE MVFR CIGS/-SN TUE NIGHT. WINDS W-SW 5KTS.
WED...VFR. WINDS NW 10G20KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...BORGHOFF
AVIATION...MPG
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
856 PM MST SAT JAN 18 2014
.UPDATE...
JUST SOME MINOR TWEAKS TO THE FORECAST THIS EVENING. I INTRODUCED
SOME CLOUD COVER A LITTLE EARLIER THAN PREVIOUS FORECAST AS
SATELLITE IMAGERY INDICATES SOME HIGH LEVEL WAVE CLOUD FORMATION
DEVELOPING IN OUR WEST AT THIS TIME.
ONLY OTHER CHANGE WAS TO DELAY ANY SRONG WIND AT BIG TIMBER AS
CURRENT PRESSURE TENDENCIES DO NOT FAVOR ANYTHING TO STRONG THERE
JUST ANY TIME SOON...AS A MATTER OF FACT THE RAP DOES NOT SHOW
VERY GOOD PRESSURE TENDECIES OVERNIGHT FOR THE BIG TIMBER AREA TO
HIT ADVISORY WIND. HOWEVER...THE VERTICAL PROFILE FOR GAP FLOW
THERE DOES SET UP BY 10 PM...SO WILL NOT TOY WITH THE HIGHLIGHT
THERE GIVEN THE MODELS DO NOT ALWAYS HANDLE PRESSURE TRENDS WELL.
LIVINGSTON ON THE OTHER HAND IS ALREADY GUSTING TO 53 MPH AND IS
THE ADVISORY THERE LOOKS IS IN GOOD SHAPE. BT
&&
.SHORT TERM...VALID FOR SUN AND MON...
THIS EVENING INTO TONIGHT...A FLATTENING RIDGE WILL CONTINUE TO
PROMOTE LEE SIDE TROUGH/LOW FORMATION ACROSS OUR WESTERN AND
CENTRAL ZONES. THIS...AND SOME SHORTWAVE ENERGY...WILL CONTINUE TO
TIGHTEN THE PRESSURE GRADIENT ACROSS THE WEST. THE GRADIENT
ORIENTATION LOOKS FAVORABLE FOR STRONG WINDS AT BOTH LIVINGSTON
AND BIG TIMBER AT VARIOUS TIMES TONIGHT INTO TOMORROW MORNING. GFS
PROGS THE GRADIENT FROM IDAHO FALLS TO LEWISTOWN AT 14MB...BUT
BOTH THE ECMWF AND NAM FORECAST THE GRADIENT TO REACH AT LEAST 20
MB TONIGHT INTO SUNDAY MORNING. WITH TWO OF THE THREE MODELS
FORECASTING A GRADIENT SUFFICIENT FOR ADVISORY-LEVEL WINDS ACROSS
THE WEST...AM CONSIDERING THE GFS AN OUTLIER HERE. MAV GUIDANCE
ALSO FORECASTS WIND SPEEDS THAT ARE USUALLY SUFFICIENT FOR
SUSTAINED WINDS NEAR 40 MPH AND GUSTS NEAR 60 MPH OVERNIGHT INTO
EARLY TOMORROW. ALREADY...BIG TIMBER IS EXPERIENCING SUSTAINED
WINDS IN THE 35 TO 37 MPH RANGE WITH GUSTS TO 44 MPH. SO...I
ISSUED A WIND ADVISORY VALID LATE THIS EVENING INTO SUNDAY MORNING
FOR THE LIVINGSTON TO BIG TIMBER TO NYE REGION. EXPECT DANGEROUS
CROSSWINDS FOR HIGH PROFILE VEHICLES IN THAT CORRIDOR. DO NOT
THINK WE WILL NEED AN ADVISORY FOR THE HARLOWTON REGION...BUT THAT
WILL NEED TO BE WATCHED AS WINDS ARE ALREADY GUSTING TO AT LEAST
40 MPH THERE AS A RESULT OF A TIGHTENING...FAVORABLY-ORIENTED
GRADIENT...WHICH IS EXPECTED TO CONTINUE OVERNIGHT.
SUNDAY MORNING...SHORTWAVE ACTIVITY OVER SOUTHERN CANADA/NORTHERN
MONTANA WILL CAUSE LOWERING HEIGHTS AT 500MB WHICH WILL ALLOW FOR
WEAK COLD ADVECTION TO FILTER INTO THE AREA. THE SHORTWAVE
ACTIVITY WILL WEAKEN THE GRADIENT ACROSS THE WEST...SO WINDS THERE
WILL GRADUALLY WEAKEN THROUGH THE MORNING. DESPITE THE COOL AIR
ADVECTION...THERE WILL BE ENOUGH SUNSHINE FOR TEMPS TO SLOWLY
CLIMB THROUGH THE DAY. STILL THINK HIGH TEMPS WILL REACH 40 OR SO
ACROSS THE EAST...AND THE LOW 50S IN LOCATIONS ACROSS THE WEST.
A STRONG COLD FRONT WILL ARRIVE SUNDAY NIGHT WITH 850MB TEMPS OF
-8C MOVING INTO NORTHEAST MONTANA BY 12Z MONDAY. THE MAIN IMPACTS
OF THIS AIR SURGE WILL BE OVER THE EAST AS THE COLDEST AIR IS
PROGGED TO SLIDE INTO NORTH DAKOTA. FARTHER WEST...AN INFLUX OF
SHORTWAVE ACTIVITY FROM THE NORTH WILL ALLOW FOR MORE ASCENT AND
THEREFORE A CHANCE OF SNOW SHOWERS OVER THE HIGHER TERRAIN SUNDAY
NIGHT.
MONDAY WILL BE A COOLER DAY BEHIND THE FRONT WITH GUSTY NW WINDS
ACROSS THE EAST...BUT DRY CONDITIONS WILL BE THE RULE. HIGHS WILL
REACH THE 20S EAST AND THE 30S AND 40S WEST. SURFACE PRESSURE
FALLS ARE EXPECTED TO TIGHTEN THE GRADIENT ACROSS THE WEST AGAIN
MONDAY NIGHT...SO I INCREASED WINDS DURING THAT TIMEFRAME FROM
LIVINGSTON TO BIG TIMBER DOWN TOWARDS NYE. STC
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
MEDIUM RANGE MODELS IN GOOD AGREEMENT WITH THE LONG RANGE MODELS
INDICATING SOME DISCREPANCIES TOWARD THE END OF THE EXTENDED
FORECAST PERIOD.
LARGE RIDGE OF HIGH PRESSURE WILL REMAIN OVER WESTERN CANADA
TUESDAY KEEPING SOUTHERN MONTANA DRY WITH ABOVE NORMAL
TEMPERATURES. RIDGE OF HIGH PRESSURE WILL RETROGRADE TO THE WEST
ON WEDNESDAY WHICH WILL ALLOW SEVERAL SHORT WAVES TO PUSH
SOUTHWARD OUT OF CANADA WEDNESDAY THROUGH FRIDAY. MOISTURE WILL
BE LIMITED WITH THESE WAVES BUT THERE IS ENOUGH FORCING ALOFT TO
MENTION A CHANCE FOR ISOLATED SNOW SHOWERS. A COLD FRONT WILL
BACKDOOR INTO SOUTHEAST MONTANA ON WEDNESDAY AND SURFACE
CONVERGENC ALONG THE FRONT WILL BRING A CHANCE OF LIGHT SNOW
MAINLY EAST OF BILLINGS. MORE ENERGY WILL MOVE ACROSS THE AREA
THURSDAY AND FRIDAY FOR A CHANCE OF LIGHT SNOW ACROSS THE AREA. DO
NOT SEE ANY SIGNIFICANT SNOW ACCUMULATIONS AS MOISTURE STILL LOOKS
LIMITED AND FORCING ALOFT IS WEAK. GFS/ECWMF/GEM ARE SHOWING
UPPER RIDGE OF HIGH PRESSURE OVER THE WEST COAST TO BEGIN
FLATTENING SATURDAY AS A STRONG SHORT WAVE MOVES INTO BRITISH
COLUMBIA. THIS WILL CAUSE HEIGHTS TO INCREASE ACROSS OUR AREA AND
ALLOW FOR WARMER TEMPERATURES. THE 12Z EC HAS SHIFTED TOWARD THE
GFS WARMER SOLUTION AND DID RAISE TEMPERATURES SLIGHTLY FOR NEXT
SATURDAY. STILL A LOT OF UNCERTAINTY ON THIS TIME PERIOD BUT
CURRENT MODEL TRENDS WOULD SHIFT ARCTIC AIR MASS FURTHER EAST OF
OUR REGION AND KEEP THE COLDEST AIR OVER NORTH DAKOTA. RICHMOND
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL ACROSS THE AREA TONIGHT. GUSTY WINDS
WILL CONTINUE ALONG THE FOOTHILLS FROM NEAR NYE...BIG TIMBER TO
LIVINGSTON THIS EVENING AND WILL INCREASE IN STRENGTH OVERNIGHT.
GUSTS TO 45 KNOTS CAN BE EXPECTED THIS EVENING...INCREASING TO 50
KNOTS LATE TONIGHT. THE GUSTY WINDS WILL DIMINISH BY LATE SUNDAY
MORNING. BT/RICHMOND
&&
.PRELIMINARY POINT TEMP/POPS...
SUN MON TUE WED THU FRI SAT
-----------------------------------------------------------
BIL 033/051 028/042 027/045 030/045 029/044 028/040 026/040
00/N 11/U 01/U 00/B 12/W 12/W 22/W
LVM 035/048 026/042 025/045 030/045 027/046 028/041 026/040
00/N 11/U 01/U 01/B 12/W 12/W 23/W
HDN 023/049 023/040 021/043 024/042 024/042 024/038 022/038
00/N 21/U 01/U 00/B 12/W 22/J 22/J
MLS 025/042 021/030 013/034 016/030 016/036 019/032 017/030
00/B 11/B 00/B 12/J 22/J 12/J 22/J
4BQ 027/044 021/033 015/037 019/032 020/039 021/035 018/032
00/U 11/U 00/B 02/J 22/J 22/J 22/J
BHK 027/041 019/026 009/031 012/026 011/033 018/029 015/027
00/B 11/N 01/B 12/J 12/J 12/J 22/J
SHR 025/048 023/037 019/042 023/040 022/043 022/040 020/039
00/U 11/U 00/U 00/B 12/W 12/J 22/J
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WIND ADVISORY IN EFFECT UNTIL 11 AM MST SUNDAY FOR ZONES
41-65-66.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
319 PM EST FRI JAN 17 2014
.SYNOPSIS...
LOW PRESSURE WILL MOVE FROM THE OHIO VALLEY INTO NEW ENGLAND TONIGHT
AND SATURDAY WITH PERIODS OF SNOW PRODUCING SOME MINOR ACCUMULATIONS
ACROSS MUCH OF THE REGION. ANOTHER STRONGER LOW WILL PASS TO THE
NORTH OF THE REGION ON SUNDAY WITH SOME ADDITIONAL LIGHT SNOW AND
STRONG WINDS. SOME LAKE ENHANCED SNOW IS POSSIBLE EAST OF THE LAKES
AS WELL. AN ARCTIC COLD FRONT WILL DROP SOUTH ACROSS THE REGION
SUNDAY NIGHT AND USHER IN THE START OF WELL BELOW AVERAGE
TEMPERATURES FOR ALL OF NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
SKIES ARE TRYING TO CLEAR ACROSS WESTERN NY THIS AFTERNOON WITHIN A
BRIEF WINDOW OF DRIER AIR. THE ONLY AREAS ABLE TO SEE FULL SUN SO
FAR HAVE BEEN DOWNWIND OF LAKE ERIE ACROSS THE NIAGARA FRONTIER AND
LAKE ERIE SHORELINE. FARTHER INLAND...LOW LEVEL MOISTURE IS ALLOWING
CUMULUS AND STRATOCUMULUS FIELDS TO FILL IN ANY CLEARING. EXPECT THE
SUNSHINE TO BE RESTRICTED TO DOWNWIND OF LAKE ERIE THROUGH MID
AFTERNOON...BUT MAY SPREAD INTO OTHER REGIONS BRIEFLY DURING THE
LATE AFTERNOON AND EARLY EVENING BEFORE CLOUDS INCREASE AGAIN AHEAD
OF THE NEXT SYSTEM.
OUR ATTENTION THEN TURNS TO A POTENT MID LEVEL LOW APPARENT IN WATER
VAPOR IMAGERY OVER THE LOWER OHIO VALLEY EARLY THIS AFTERNOON. SHORT
TERM MODEL GUIDANCE TRACKS THIS SYSTEM ACROSS WESTERN PA AND INTO
NEW ENGLAND TONIGHT AND SATURDAY...WITH SEVERAL SMALLER SCALE
SHORTWAVES AND SPOKES OF STRONG VORTICITY PRODUCING PERIODS OF
ENHANCED LIFT ACROSS OUR REGION. TOTAL SNOW AMOUNTS WILL BE
RELATIVELY MINOR WITH THIS SYSTEM...BUT IT COULD COME IN A FEW QUICK
BURSTS WHICH WILL IMPACT TRAVEL TO SOME EXTENT AND MAKING FORECAST
TIMING DIFFICULT.
MESOSCALE MODEL GUIDANCE INCLUDING THE OPERATIONAL NAM AND TO SOME
EXTENT THE CANADIAN GEM AND HRRR SUGGEST THE FIRST BURST OF SNOW
WILL LIFT FROM SOUTH TO NORTH ACROSS WESTERN NY THIS EVENING. THE
BURST MAY REACH CHAUTAUQUA AND CATTARAUGUS COUNTY BY 23Z-00Z...THEN
LIFT ALMOST DUE NORTH TO THE NIAGARA FRONTIER BY 02Z-03Z BEFORE
LIFTING INTO SOUTHERN ONTARIO AND LAKE ONTARIO BY MIDNIGHT. UPSTREAM
RADARS SHOW THIS FEATURE ALREADY WELL DEFINED IN EASTERN OHIO...SO
THAT GIVES SOME CREDENCE TO THESE HIGH RESOLUTION MODELS. THIS MAY
PRODUCE A QUICK BURST OF AN INCH OR SO OF SNOW IN ABOUT AN HOUR
ACROSS WESTERN NY...ENOUGH TO PRODUCE WIDESPREAD SLIPPERY TRAVEL
ACROSS WESTERN NY.
THIS FIRST BATCH SHOULD BE MAINLY CONFINED TO WESTERN NY. LATER
TONIGHT ANOTHER PERIOD OF ASCENT WILL OVERSPREAD THE REGION AS THE
MAIN MID LEVEL CLOSED LOW APPROACHES. SATURDAY MORNING A WEAK COMMA
HEAD OF LIGHT TO MODERATE SNOW SHOULD DEVELOP ACROSS THE FINGER
LAKES AND WESTERN NY AS THE SHARP MID LEVEL LOW MAXIMIZES ASCENT IN
THAT AREA...AND A SURFACE LOW DEEPENS OVER THE LOWER HUDSON VALLEY
AND SOUTHERN NEW ENGLAND WITH A REGION OF DEFORMATION DEVELOPING ON
ITS NORTHWEST FLANK. EXPECT A STEADY SNOW ACROSS A GOOD PORTION OF
THE AREA SATURDAY MORNING...WITH THE MORE MODERATE RATES FROM THE
FINGER LAKES TO SOUTHERN TUG HILL REGION...INCLUDING COUNTIES ALONG
THE SOUTHEAST SHORE OF LAKE ONTARIO. THIS MAY PRODUCE ADDITIONAL
AMOUNTS OF 2-3 INCHES IN THESE AREAS. ELSEWHERE ACROSS WESTERN NY
AND NEAR THE SAINT LAWRENCE RIVER EXPECT PERIODS OF LIGHTER SNOW
WITH ADDITIONAL AMOUNTS AROUND AN INCH.
BETWEEN THE SEVERAL ROUNDS OF SNOW TONIGHT AND SATURDAY...EXPECT
TOTAL AMOUNTS TO BE 1-2 INCHES ACROSS THE NIAGARA FRONTIER AND NEAR
THE SAINT LAWRENCE...WITH 2-4 INCHES FROM THE WESTERN SOUTHERN TIER
EAST ACROSS THE FINGER LAKES TO OSWEGO COUNTY AND THE SOUTHERN TUG
HILL. THE FAR WESTERN SOUTHERN TIER MAY HAVE LESS SYNOPTIC SNOW THAN
OTHER AREAS...BUT UPSLOPE FLOW AND SOME LAKE ENHANCEMENT SHOULD
BOOST THESE AREAS TO THE 2-4 INCH RANGE AS WELL.
THIS SNOW WILL SLOWLY TAPER OFF TO FLURRIES FROM WEST TO EAST
SATURDAY AFTERNOON...WITH SNOW LINGERING THE LONGEST EAST AND
SOUTHEAST OF LAKE ONTARIO. HIGHS ON SATURDAY WILL RANGE FROM ONLY
AROUND 20 ACROSS THE WESTERN SOUTHERN TIER WHERE MORE COLD AIR WRAPS
IN BEHIND THE CLOSED LOW...TO THE LOWER 30S ACROSS CENTRAL NY AND
THE NORTH COUNTRY.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
SATURDAY NIGHT...AN AREA OF HIGH PRESSURE WILL BEGIN TO NOSE NORTHWARD
BRINGING DRIER AIR AND ALSO BACKING OUR WINDS AROUND TO SOUTHERLY.
THIS SHOULD ALLOW FOR A DRY START TO THE NIGHT SOUTH OF LAKE
ONTARIO...WHILE TO THE EAST OF LAKE ONTARIO A WESTERLY FLOW OVER THE
LAKE WILL CONTINUE LIGHT SNOW SHOWERS...FIRST FROM THE DEPARTING
UPPER LEVEL DISTURBANCE AND THEN SOME WEAK LAKE EFFECT SNOW. THIS
BAND OF SNOW LATER SATURDAY NIGHT SHOULD LIFT NORTHWARD THEN WEAKEN
FURTHER AS SOME DRY AIR GETS ENTRAINED INTO THE SNOWBAND. OVERALL
SEVERAL INCHES OF SNOW WILL FALL FROM THIS BAND...BUT FOR NOW FEEL
THAT TOTALS WILL REMAIN BELOW 4 INCHES/12HRS.
LATER SATURDAY NIGHT SEVERAL SHORTWAVES TO OUR WEST WILL DIVE
SOUTHWARD INTO A LONGWAVE TROUGH AND BRING THE TROUGH ACROSS THE
EASTERN GREAT LAKES REGION LATER SATURDAY NIGHT AND SUNDAY. LIFT
AHEAD OF THIS TROUGH COMBINED WITH ABUNDANT LOW LEVEL MOISTURE
WILL ALLOW FOR LIGHT SYNOPTIC SNOW TO REACH FAR WNY LATE SATURDAY
NIGHT AND THEN EXPAND EASTWARD ACROSS THE REGION ON SUNDAY. WITHIN
THESE SNOW SHOWERS LAKE ENHANCEMENT WILL OCCUR DOWNWIND OF BOTH
LAKES AS A SOUTHWEST FLOW UP BOTH LAKE ERIE AND OVER LAKE ONTARIO
WILL CREATE ADDITIONAL INSTABILITY AND ALLOW FOR ENHANCED SNOW
SHOWERS. WHILE LAKE INDUCED EQUILIBRIUM LEVELS OFF LAKE ERIE ARE ONLY
AROUND 4K FEET...THEY WILL BE GREATER OFF LAKE ONTARIO AND LAKE
SNOWS IN ADDITION TO THE SYNOPTIC SNOWS MAY BRING ADVISORY LEVEL
SNOWS SUNDAY TO THE NORTH COUNTRY.
IN ADDITION TO THE SNOWS ON SUNDAY...IT WILL BECOME RATHER WINDY
WITH SOUTHWEST WINDS INCREASING WITHIN A TIGHTENING SURFACE PRESSURE
GRADIENT. THIS WILL NOT BE YOUR TYPICAL DEEPENING LOW PASSING TO OUR
NORTH AND WEST...BUT RATHER A DEEPENING LOW PASSING TO OUR NORTH
ACROSS SOUTHERN CANADA...ONE THAT WILL BE DRIVING A STRONG ARCTIC
FRONT TOWARDS OUR REGION. WINDS MAY BRIEFLY REACH ADVISORY LEVELS
ACROSS THE NIAGARA FRONTIER IN THE TYPICAL GUSTY AREAS DOWNWIND OF
THE LAKE ON A SOUTHWEST WIND. WINDS MAY ALSO REACH ADVISORY LEVELS
ACROSS JEFFERSON COUNTRY AND THE SAINT LAWRENCE VALLEY...WHICH WILL
BE CLOSER TO THE ISALLOBARIC COUPLET. WINDS COMBINED WITH SNOW WILL
BRING SOME LOWERED VISIBILITIES THROUGH THE DAY.
SUNDAY NIGHT A SHARP ARCTIC FRONT WILL BE DROPPING SOUTHWARD FROM
CANADA FROM THIS DEEPENING AREA OF LOW PRESSURE THAT WILL BE
ADVANCING EASTWARD ACROSS SOUTHERN CANADA. A RIBBON OF ENHANCED LIFT
FROM THIS FRONT COMBINED WITH LOW LEVEL MOISTURE WILL BRING A BAND
OF SNOW SHOWERS...FIRST ACROSS THE SAINT LAWRENCE VALLEY AND
THOUSAND ISLAND REGION EARLY SUNDAY NIGHT...AND DROPPING
SOUTHWARD...REACHING THE SOUTHERN SHORELINE OF LAKE ONTARIO AROUND
MIDNIGHT...AND THEN POINTS SOUTHWARD THROUGH THE REMAINDER OF THE
NIGHT. BEHIND THIS FRONT TEMPERATURES WILL QUICKLY DROP...AND WINDS
VEER TO NORTHWESTERLY. BY THE END OF SUNDAY NIGHT...TEMPERATURES
WILL LIKELY HAVE FALLEN INTO THE LOW SINGLE DIGITS ACROSS THE NORTH
COUNTRY AND TEENS ELSEWHERE.
MONDAY COLD AIR ADVECTION BEHIND THE COLD FRONT WILL RETURN OUR
REGION INTO THE DEEP FREEZE. 850 HPA DROPPING DOWN TO ABOUT -20C
THROUGH THE DAY WILL NOT ALLOW FOR MORNING TEMPERATURES TO IMPROVE
MUCH. HIGHS MONDAY WILL ONLY BE A FEW DEGREES WARMER THAN THE
MORNING READINGS. SOME LIMITED LAKE EFFECT WILL LIKELY ORGANIZE
SNOWS SOUTH OF THE LAKES BEHIND THE ARCTIC FRONT AS NORTHWESTERLY
WINDS ALIGN. DRIER AIR ASSOCIATED WITH THIS COLD AIRMASS WILL LIKELY
HOLD SNOW ACCUMULATIONS MANAGEABLE SOUTH OF THE LAKES. MONDAY NIGHT
INCREASING WIND SHEAR WILL LIKELY BREAK APART ANY REMAINING LAKE
EFFECT SNOW BANDS...WHILE AS WINDS RELAX SOME THROUGH THE NIGHT
TEMPERATURES DROP INTO THE LOW SINGLE DIGITS...AND BELOW ZERO ACROSS
THE TRADITIONALLY COLDER SPOTS IN VALLEYS SOUTH OF LAKE ONTARIO.
ACROSS THE NORTH COUNTRY...OVER A FRESH SNOWPACK TEMPERATURES WILL
BOTTOM OUT...POSSIBLY INTO THE NEGATIVE TEENS MONDAY NIGHT. WINDS
MAY STAY STRONG ENOUGH MONDAY NIGHT TO WARRANT WIND CHILL HEADLINES.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
THIS TIME PERIOD WILL FEATURE TEMPERATURES THAT WILL AVERAGE WELL
BELOW NORMAL...WITH THE COLDEST DAYS EXPECTED EARLY IN THE TIME
PERIOD.
TO START THIS TIME PERIOD AN ANOMALOUSLY +2SD RIDGE WILL BE EXTENDED
OVER THE WESTERN HALF OF NOAM WHILE A -1SD TROUGH WILL BE FOUND OVER
EASTERN NOAM. THIS PATTERN...WITH THE RIDGE AXIS EXTENDING TO NEAR
THE ARCTIC CIRCLE WILL ALLOW FOR A ARCTIC AIRMASS TO DROP
SOUTHWARD...FULLY ENTRENCHED OVER THE GREAT LAKES REGION BY THE
START OF THE TIME PERIOD. TEMPERATURES AT 850 HPA WILL PLUMMET TO
AROUND -22C TO -24C TUESDAY BEFORE THE AIRMASS MODIFIES SOME.
THIS COLD AIRMASS WILL ALSO CREATE A FAIR AMOUNT OF LAKE INSTABILITY
FOR THIS TIME OF YEAR WITH LAKE INDUCED EQUILIBRIUM LEVELS CLIMBING
UPWARDS TO 10K FEET OFF BOTH LAKES TUESDAY THROUGH THURSDAY. THIS
WILL KEEP CHANCES FOR SNOW SHOWERS MID WEEK NEAR THE GREAT
LAKES...THOUGH SOME OF THE FINER DETAILS OF WIND DIRECTION ARE STILL
A LITTLE UNCERTAIN AT THIS TIME. WHILE IT MAY BE SNOWY PERIOD NEXT
WEEK...THE DRIER NATURE ASSOCIATED WITH THIS ARCTIC AIRMASS WILL
LIKELY KEEP DAILY SNOW TOTALS MANAGEABLE...WITH NO ONE DAY
SIGNIFICANT ACCUMULATIONS EXPECTED.
AS THE INITIAL COLD AIRMASS MODIFIES AND SHIFTS EASTWARD A RIDGE OF
HIGH PRESSURE WILL EXTEND NORTHWARD ACROSS THE EASTERN GREAT LAKES
REGION. THIS WILL BRING A BRIEF PERIOD OF DRY WEATHER AS LAKE SNOWS
DIMINISH...AND BEFORE THE NEXT ARCTIC FRONT/COLD BLAST THAT WILL
LIKELY REACH US NEXT WEEKEND.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
MAINLY VFR WILL PREVAIL THROUGH THE REST OF THE AFTERNOON ACROSS
MOST OF THE REGION...WITH SOME MVFR CIGS LINGERING ACROSS THE HIGHER
TERRAIN EAST OF LAKE ONTARIO.
A POTENT MID LEVEL DISTURBANCE AND WEAK SURFACE LOW WILL THEN
APPROACH FROM THE OHIO VALLEY LATER THIS EVENING. THIS MAY PRODUCE A
QUICK BURST OF MODERATE SNOW ACROSS WESTERN NY FOR AN HOUR OR TWO
WITH VSBY APPROACHING AIRFIELD MINIMUMS BRIEFLY. AFTER THIS INITIAL
BURST OF SNOW...THERE MAY BE A BREAK FOLLOWED BY MORE SNOW LATER
TONIGHT INTO SATURDAY. THE SECOND BATCH OF SNOW SHOULD FOCUS MOST OF
ITS MODERATE SNOW ON THE FINGER LAKES AND CENTRAL NY...WITH LIGHTER
SNOW EXTENDING BACK INTO WESTERN NY AND THE NORTH COUNTRY. EXPECT
PERIODS OF IFR VSBY WITH THIS AS WELL. THE SNOW WILL SLOWLY TAPER
OFF TO FLURRIES FROM WEST TO EAST SATURDAY AFTERNOON WITH IMPROVING
VSBY.
CIGS WILL DROP DOWN TO MVFR WITHIN THE HEAVIER SNOW SHOWERS THIS
EVENING...THEN EXPECT A TREND OF MORE WIDESPREAD MVFR CIGS WITH IFR
ACROSS HIGHER TERRAIN LATE TONIGHT THROUGH SATURDAY AS LOW LEVEL
MOISTURE DEEPENS...AND UPSLOPE FLOW INCREASES.
OUTLOOK...
SUNDAY THROUGH WEDNESDAY...VFR...WITH OCCASIONAL RESTRICTIONS TO
MVFR/IFR IN SCATTERED TO NUMEROUS SNOW SHOWERS.
&&
.MARINE...
PERIODS OF MODERATE SOUTHWEST WINDS WILL CONTINUE ON LAKES ERIE AND
ONTARIO TONIGHT THROUGH SUNDAY MORNING WITH SMALL CRAFT ADVISORY
CONDITIONS MOST OF THE TIME. A STRONGER AREA OF LOW PRESSURE WILL
PASS BY WELL NORTH OF THE REGION ACROSS QUEBEC SUNDAY AFTERNOON AND
SUNDAY NIGHT. A STRONG ARCTIC FRONT ASSOCIATED WITH THIS LOW WILL
PUSH SOUTH AND TIGHTEN THE PRESSURE GRADIENT...ALLOWING FOR WINDS TO
APPROACH OR REACH GALE FORCE. WITH THIS IN MIND...WE HAVE RAISED A
GALE WATCH FOR SUNDAY AND SUNDAY NIGHT ON BOTH LAKES.
&&
.CLIMATE...
THE COLD THAT DEVELOPS NEXT WEEK IS VERY LIKELY TO LAST THROUGH THE
END OF JANUARY AND POSSIBLY INTO EARLY FEBRUARY WITH MOST DAYS
SEEING BELOW AVERAGE OR EVEN WELL BELOW AVERAGE TEMPERATURES.
THE D+11 TOOLS FROM CPC WHICH TAKE A 7 DAY RUNNING MEAN OF THE GEFS
ENSEMBLE MEAN FROM JANUARY 24-30 SHOW A VERY DEEP LONGWAVE TROUGH
OVER EASTERN NORTH AMERICA WITH A SHARP RIDGE ALONG THE WEST COAST
EXTENDING ALL THE WAY NORTH TO ALASKA AND BEYOND TO THE NORTH POLE.
TO SEE SUCH AMPLIFICATION IN A ONE WEEK AVERAGE OF GEFS MEAN 500MB
HEIGHT IS VERY IMPRESSIVE...SINCE IT IS A TIME AVERAGED PRODUCT OF
SOMETHING THAT IS ALREADY AN AVERAGE OF THE VARIOUS ENSEMBLE
MEMBERS. BOTTOM LINE...THIS SHOWS VERY GOOD AGREEMENT AMONGST GEFS
ENSEMBLE MEMBERS FOR A LONG PERIOD OF HIGHLY AMPLIFIED LONGWAVE
FLOW. THE ECMWF ENSEMBLE MEAN ALSO SHOWS A SIMILAR PATTERN.
THE PATTERN SHOWN BY THE ENSEMBLE MEAN IS A STRONG POSITIVE PNA
PATTERN...WELL KNOWN FOR DELIVERING ANY COLD AIR AVAILABLE INTO OUR
PORTION OF NORTH AMERICA. THIS LONGWAVE PATTERN ALSO SUPPORTS THE
POTENTIAL FOR CROSS POLAR FLOW...ALLOWING SIBERIAN AIR TO CROSS THE
POLES AND SPILL INTO NORTHERN CANADA. FROM THERE...THE PATTERN
SUPPORTS PIECES OF THIS COLD MOVING INTO THE NORTHERN TIER OF THE
UNITED STATES FROM THE UPPER MISSISSIPPI VALLEY EAST ACROSS THE
GREAT LAKES AND NEW ENGLAND.
THE D+11 TOOLS ALSO LOOK BACK TO FIND ANALOGS THAT CLOSELY MATCH
THIS 500MB PATTERN TO PAST EVENTS...GIVING THE 10 BEST MATCHES FOR
ANALOG DATES. A LOOK BACK AT SURFACE CONDITIONS DURING THESE ANALOG
DATES SHOW THE VAST MAJORITY OF THEM HAD SURFACE TEMPERATURES OF
15-20 DEGREES BELOW AVERAGE.
TO SUM UP...THE PATTERN STRONGLY SUPPORTS MUCH BELOW AVERAGE
TEMPERATURES MOST OF THE TIME FROM NEXT WEEK THROUGH THE END OF THE
MONTH AND POSSIBLY INTO EARLY FEBRUARY. OF COURSE WITH COLD AIR
COMES LAKE EFFECT POTENTIAL...BUT THE DETAILS WHICH DRIVE LOCATION
AND AMOUNTS ARE NOT APPARENT AT THIS TIME RANGE.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...GALE WATCH FROM SUNDAY MORNING THROUGH LATE SUNDAY NIGHT FOR
LEZ020-040-041.
SMALL CRAFT ADVISORY UNTIL 11 AM EST SUNDAY FOR LEZ040-041.
SMALL CRAFT ADVISORY FROM 8 AM TO 10 PM EST SATURDAY FOR
LEZ020.
GALE WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING
FOR LOZ030-042>045-062>065.
SMALL CRAFT ADVISORY FROM 9 AM SATURDAY TO 11 AM EST
SUNDAY FOR LOZ042-043.
SMALL CRAFT ADVISORY FROM 1 PM SATURDAY TO 11 AM EST
SUNDAY FOR LOZ044-045.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...HITCHCOCK
MARINE...HITCHCOCK
CLIMATE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS BUFFALO NY
123 PM EST FRI JAN 17 2014
.SYNOPSIS...
LOW PRESSURE WILL MOVE FROM THE OHIO VALLEY INTO NEW ENGLAND TONIGHT
AND SATURDAY WITH PERIODS OF SNOW PRODUCING SOME MINOR ACCUMULATIONS
ACROSS MUCH OF THE REGION. ANOTHER STRONGER LOW WILL PASS TO THE
NORTH OF THE REGION ON SUNDAY WITH SOME ADDITIONAL LIGHT SNOW AND
STRONG WINDS. SOME LAKE ENHANCED SNOW IS POSSIBLE EAST OF THE LAKES
AS WELL. AN ARCTIC COLD FRONT WILL DROP SOUTH ACROSS THE REGION
SUNDAY NIGHT AND USHER IN THE START OF WELL BELOW AVERAGE
TEMPERATURES FOR ALL OF NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
SKIES ARE TRYING TO CLEAR ACROSS WESTERN NY THIS AFTERNOON WITHIN A
BRIEF WINDOW OF DRIER AIR. SO FAR ONLY AREAS DOWNWIND OF LAKE ERIE
HAVE CLEARED ACROSS THE NIAGARA FRONTIER AND LAKE ERIE SHORELINE.
FARTHER INLAND...LOW LEVEL MOISTURE IS ALLOWING CUMULUS AND
STRATOCUMULUS FIELDS TO FILL IN ANY CLEARING. EXPECT THE SUNSHINE TO
BE RESTRICTED TO DOWNWIND OF LAKE ERIE THROUGH MID AFTERNOON...BUT
MAY SPREAD INTO OTHER REGIONS BRIEFLY DURING THE LATE AFTERNOON AND
EARLY EVENING BEFORE CLOUDS INCREASE AGAIN AHEAD OF THE NEXT SYSTEM.
OUR ATTENTION THEN TURNS TO A POTENT MID LEVEL LOW APPARENT IN WATER
VAPOR IMAGERY OVER THE LOWER OHIO VALLEY EARLY THIS AFTERNOON. SHORT
TERM MODEL GUIDANCE TRACKS THIS SYSTEM ACROSS WESTERN PA AND INTO
NEW ENGLAND TONIGHT AND SATURDAY...WITH SEVERAL SMALLER SCALE
SHORTWAVES AND SPOKES OF STRONG VORTICITY PRODUCING PERIODS OF
ENHANCED LIFT ACROSS OUR REGION. TOTAL SNOW AMOUNTS WILL BE
RELATIVELY MINOR WITH THIS SYSTEM...BUT IT COULD COME IN A FEW QUICK
BURSTS WHICH WILL IMPACT TRAVEL TO SOME EXTENT AND MAKING FORECAST
TIMING DIFFICULT.
MESOSCALE MODEL GUIDANCE INCLUDING THE OPERATIONAL NAM AND TO SOME
EXTENT THE CANADIAN GEM AND HRRR SUGGEST THE FIRST BURST OF SNOW
WILL LIFT FROM SOUTH TO NORTH ACROSS WESTERN NY THIS EVENING. THE
BURST MAY REACH CHAUTAUQUA AND CATTARAUGUS COUNTY BY 23Z-00Z...THEN
LIFT ALMOST DUE NORTH TO THE NIAGARA FRONTIER BY 02Z-03Z BEFORE
LIFTING INTO SOUTHERN ONTARIO AND LAKE ONTARIO BY MIDNIGHT. UPSTREAM
RADARS SHOW THIS FEATURE ALREADY WELL DEFINED IN EASTERN OHIO...SO
THAT GIVES SOME CREDENCE TO THESE HIGH RESOLUTION MODELS. THIS MAY
PRODUCE A QUICK BURST OF AN INCH OR SO OF SNOW IN ABOUT AN HOUR
ACROSS WESTERN NY...ENOUGH TO PRODUCE WIDESPREAD SLIPPERY TRAVEL
ACROSS WESTERN NY.
THIS FIRST BATCH SHOULD BE MAINLY CONFINED TO WESTERN NY. LATER
TONIGHT ANOTHER PERIOD OF ASCENT WILL OVERSPREAD THE REGION AS THE
MAIN MID LEVEL CLOSED LOW APPROACHES. SATURDAY MORNING A WEAK COMMA
HEAD OF LIGHT TO MODERATE SNOW SHOULD DEVELOP ACROSS THE FINGER
LAKES AND WESTERN NY AS THE SHARP MID LEVEL LOW MAXIMIZES ASCENT IN
THAT AREA...AND A SURFACE LOW DEEPENS OVER THE LOWER HUDSON VALLEY
AND SOUTHERN NEW ENGLAND WITH A REGION OF DEFORMATION DEVELOPING ON
ITS NORTHWEST FLANK. EXPECT A STEADY SNOW ACROSS A GOOD PORTION OF
THE AREA SATURDAY MORNING...WITH THE MORE MODERATE RATES FROM THE
FINGER LAKES TO SOUTHERN TUG HILL REGION...INCLUDING COUNTIES ALONG
THE SOUTHEAST SHORE OF LAKE ONTARIO. THIS MAY PRODUCE ADDITIONAL
AMOUNTS OF 2-3 INCHES IN THESE AREAS. ELSEWHERE ACROSS WESTERN NY
AND NEAR THE SAINT LAWRENCE RIVER EXPECT PERIODS OF LIGHTER SNOW
WITH ADDITIONAL AMOUNTS AROUND AN INCH.
BETWEEN THE SEVERAL ROUNDS OF SNOW TONIGHT AND SATURDAY...EXPECT
TOTAL AMOUNTS TO BE 1-2 INCHES ACROSS THE NIAGARA FRONTIER AND NEAR
THE SAINT LAWRENCE...WITH 2-4 INCHES FROM THE WESTERN SOUTHERN TIER
EAST ACROSS THE FINGER LAKES TO OSWEGO COUNTY AND THE SOUTHERN TUG
HILL. THE FAR WESTERN SOUTHERN TIER MAY HAVE LESS SYNOPTIC SNOW THAN
OTHER AREAS...BUT UPSLOPE FLOW AND SOME LAKE ENHANCEMENT SHOULD
BOOST THESE AREAS TO THE 2-4 INCH RANGE AS WELL.
THIS SNOW WILL SLOWLY TAPER OFF TO FLURRIES FROM WEST TO EAST
SATURDAY AFTERNOON...WITH SNOW LINGERING THE LONGEST EAST AND
SOUTHEAST OF LAKE ONTARIO. HIGHS ON SATURDAY WILL RANGE FROM ONLY
AROUND 20 ACROSS THE WESTERN SOUTHERN TIER WHERE MORE COLD AIR WRAPS
IN BEHIND THE CLOSED LOW...TO THE LOWER 30S ACROSS CENTRAL NY AND
THE NORTH COUNTRY.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
DESPITE THE VERY INTERESTING WEATHER PATTERN...THERE WILL BE LITTLE
ACTUAL WEATHER TO TALK ABOUT ACROSS OUR FORECAST AREA DURING THIS
PERIOD. THE EXCEPTION WILL BE THE POTENTIAL FOR SIGNIFICANT LAKE
EFFECT EAST OF LAKE ONTARIO...BUT LETS LOOK AT THE OVERALL PICTURE
FIRST.
AS ADVERTISED FOR THE PAST SEVERAL DAYS...A STRONG +PNA PATTERN WILL
BE LOCKED IN PLACE DURING THIS PERIOD AS AN ANOMALOUSLY ROBUST RIDGE
WILL EXTEND FROM CALIFORNIA AND BRITISH COLUMBIA UP ACROSS THE NORTH
SEA TO NORTHERN SIBERIA. THIS RIDGE WILL HAVE THE MAGNITUDE OF ONE
THAT DEVELOPS AN AVERAGE OF ONCE EVERY FIVE YEARS OR SO...AND THAT
IS BASED SOLELY ON ITS HGT VALUES AND NOT IN REGARDS TO ITS
PERSISTENCE...WHICH IS EXPONENTIALLY MORE IMPRESSIVE. THIS UNUSUAL
FEATURE WILL CONTINUE TO SUPPLY RECORD WARMTH TO PARTS OF BRITISH
COLUMBIA (THANK GOODNESS THE WINTER OLYMPICS ARE NOT THERE THIS YR)
AND WILL KEEP HISTORICALLY DRY CONDITIONS INTACT OVER CALIFORNIA.
WITH EVERY IMPOSING RIDGE THERE IS LIKELY AN EQUALLY IMPRESSIVE
TROUGH...AND IF YOU HAVE BEEN READING THESE DISCUSSIONS OF LATE YOU
WILL KNOW THAT THIS CASE WILL BE NO DIFFERENT. A DEEP FULL LATITUDE
TROUGH WILL BE CEMENTED IN PLACE OVER THE EASTERN HALF OF NORTH
AMERICA. WHILE THIS WILL MOST CERTAINLY PRODUCE A FEED OF VERY COLD
AIR FROM THE CANADIAN ARCTIC...GYRES IN PLACE NEAR THE CIRCLE WILL
TEMPORARILY PREVENT A CROSS POLAR FLOW FROM REINFORCING THE FRIGID
AIRMASS. 00Z ENSEMBLES SUGGEST THAT THIS COULD CHANGE DURING THE
LONG TERM PERIOD THOUGH.
SUMMING THIS UP...TEMPERATURES WILL AVERAGE BELOW NORMAL DURING THIS
PERIOD WITH A DOWNWARD TREND TOWARDS FRIGID WEATHER AS WE HEAD INTO
NEXT WEEK. IN TERMS OF THE DAY TO DAY DETAILS...
AN EXITING MID LEVEL DISTURBANCE WILL EXIT THE FINGER LAKES AND
EASTERN LAKE ONTARIO REGIONS SATURDAY MORNING...BUT NOT BEFORE
PRODUCING A FEW MORE HOURS OF LIGHT SNOW FOR SITES EAST OF THE
GENESEE RIVER. ONLY EXPECT AN ADDITIONAL INCH OR TWO OF ACCUMULATION
(ON TOP OF MINOR ACCUMS FROM THE PREVIOUS NIGHT)...OTHERWISE
FLURRIES WILL INTERMINGLE WITH BREAKS OF SUN...WITH THE GREATEST
CHANCE FOR ANY SUN COMING OVER THE FAR WESTERN COUNTIES. HIGH TEMPS
WILL BE IN THE 20S.
THE SUBTLE RIDGING WILL BRING FAIR WEATHER TO THE REGION FOR THE
FIRST HALF OF SATURDAY NIGHT...THEN A HEALTHY MID LEVEL DISTURBANCE
WILL PASS BY TO OUR SOUTH WHILE ITS ATTENDANT SFC TROUGH WILL MAKE
ITS WAY OVER LAKE ERIE. THIS COULD TOUCH OFF SOME LIGHT SNOW SHOWERS
OVER THE WESTERN COUNTIES WHILE SOME WEAK LAKE SNOWS WILL BE
POSSIBLE NORTH OF THE TUG HILL. OVERNIGHT LOWS WILL GENERALLY BE IN
THE TEENS TO NEAR 20.
ON SUNDAY...THE PASSING OF A LONGWAVE TROUGH WILL HELP TO GENERATE
SOME NUISANCE SCATTERED SNOW SHOWERS. THIS ACTIVITY SHOULD BE
ENHANCED A BIT EAST AND NORTHEAST OF BOTH LAKES WHERE A CAP OF 6K FT
AND A MINIMALLY SHEARED ENVIRONMENT WILL BE IN PLACE. SNOW ACCUMS
WILL BE UNDER AN INCH IN MOST AREAS...WITH MORE SIGNIFICANT SNOWS
POSSIBLE NEAR AND NORTH OF THE TUG HILL WHERE SUBSTANTIAL LAKE
EFFECT WILL BE LIKELY. AFTERNOON TEMPS WILL GENERALLY RANGE FROM 25
TO 30.
IT WILL BECOME WINDY SUNDAY AFTERNOON AND EVENING...AS A WELL
ALIGNED...INCREASINGLY TIGHT PRESSURE GRADIENT FROM H925 TO H7 WILL
SET UP AHEAD OF AN APPROACHING ARCTIC COLD FRONT. WINDS OF 50-55
KNOTS AT 3K FT WILL BE FOUND JUST AHEAD OF THIS FRONT. CONTINUITY OF
SFC WINDS AVERAGING 25 TO 35 KNOTS STILL LOOK REASONABLE NEAR THE
LAKES...SO THIS WILL BE CLOSE TO ADVISORY CRITERIA. WILL MENTION
THIS IN THE UPDATED HWO PRODUCT.
THE ARCTIC COLD FRONT WILL DROP ACROSS THE REGION SUNDAY NIGHT. THIS
FRONT WILL USHER IN H85 TEMPS AS LOW AS -20C (OVR LK ONT) BY
DAYBREAK MONDAY WHILE GENERATING ADDITIONAL SNOW SHOWERS.
FINALLY FOR MONDAY AND MONDAY NIGHT...A DEEP NORTHWEST FLOW WILL
ADVECT SUB -22C H85 AIR DOWN ACROSS THE LOWER GREAT LAKES AND OVER
OUR REGION. HAVE LOWERED MONDAY HIGH TEMPS AS A RESULT...WITH THE
HIGHEST TEMPS LIKELY OCCURRING EARLY THEN HOLDING STEADY OR FALLING
THROUGH THE TEENS IN THE AFTERNOON. MONDAY NIGHT...MERCURY READINGS
WILL DROP INTO THE SINGLE DIGITS FOR ALL BUT THE NORTH COUNTRY WHERE
NEGATIVE NUMBERS WILL BE POSSIBLE. THESE TEMPS WILL BE AT LEAST 15
DEG F BELOW NORMAL VALUES.
THE FRIGID NORTHWEST FLOW WILL ALSO SUPPORT SOME LAKE EFFECT SNOW
SHOWERS...ESPECIALLY SOUTHEAST OF LK ONTARIO AS THE STILL MAINLY
OPEN WATERS OF THAT LAKE WILL GENERATE A STRONGER RESPONSE.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
TEMPERATURES WILL AVERAGE WELL BELOW NORMAL THROUGH...AND LIKELY
WELL BEYOND...THIS FORECAST PERIOD AS ALL AVAILABLE ENSEMBLES ARE IN
STRONG AGREEMENT THAT AN UNUSUALLY STRONG +PNA PATTERN WILL PERSIST.
THE LAST TIME WE EXPERIENCED A +PNA OF THIS MAGNITUDE WAS THE WINTER
OF 2009-2010 WHEN TEMPERATURES EVERY WINTER MONTH AVERAGED BELOW
NORMAL. IT IS INTERESTING TO NOTE THAT SIMILAR WEST COAST TO SIBERIA
RIDGING WAS IN PLACE DURING THE INFAMOUS WINTER OF 1976-77.
THIS PATTERN WILL SUPPORT A PERSISTENT FLOW OUT OF THE CANADIAN
ARCTIC...WITH ENSEMBLES NOW SUGGESTING REINFORCING ARCTIC AIR OUT OF
SIBERIA WITHIN TIMES OF CROSS POLAR FLOW. IF THIS WERE TO VERIFY...
IT IS LIKELY THAT WE WOULD EXPERIENCE WELL BELOW NORMAL TEMPERATURES
BEYOND THIS FORECAST PERIOD...THROUGH NEXT WEEKEND.
WHILE IT WILL BE QUITE COLD DURING THIS PERIOD...THE DOMINATING
NORTHERN STREAM WILL KEEP THE NORMALLY MORE ACTIVE SUB TROPICAL JET
WELL TO OUR SOUTH...THUS SPARING US FROM ANY SIGNIFICANT PCPN
EVENTS. INSTEAD...THE FRIGID WEATHER WILL ENCOURAGE PERSISTENT LAKE
SNOWS SOUTH AND SOUTHEAST OF THE LAKES. DAILY SNOWFALL FROM THIS
ACTIVITY IS NOT EXPECTED TO BE SIGNIFICANT...ALTHOUGH TOTAL AMOUNTS
THROUGH THE PERIOD COULD ADD UP TO RESPECTABLE AMOUNTS.
ENJOY THE COLD WEATHER.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
A MIX OF VFR AND MVFR CIGS WILL CONTINUE THIS AFTERNOON ACROSS THE
REGION WITH MVFR FAVORED ACROSS HIGHER TERRAIN AND VFR AT LOWER
ELEVATIONS. SKIES ARE ALREADY CLEARING NORTHEAST OF LAKE ERIE
INCLUDING KBUF-KIAG...AND THIS CLEARING TREND MAY BRIEFLY SPREAD
ACROSS THE REST OF THE AREA DURING THE LATE AFTERNOON AND EARLY
EVENING.
A POTENT MID LEVEL DISTURBANCE AND WEAK SURFACE LOW WILL THEN
APPROACH FROM THE OHIO VALLEY LATER THIS EVENING. THIS MAY PRODUCE A
QUICK BURST OF MODERATE SNOW ACROSS WESTERN NY FOR AN HOUR OR TWO
WITH VSBY APPROACHING AIRFIELD MINIMUMS BRIEFLY. AFTER THIS INITIAL
BURST OF SNOW...THERE MAY BE A BREAK FOLLOWED BY MORE SNOW LATER
TONIGHT INTO SATURDAY. THE SECOND BATCH OF SNOW SHOULD FOCUS MOST OF
ITS MODERATE SNOW ON THE FINGER LAKES AND CENTRAL NY...WITH LIGHTER
SNOW EXTENDING BACK INTO WESTERN NY AND THE NORTH COUNTRY. EXPECT
PERIODS OF IFR VSBY WITH THIS AS WELL. THE SNOW WILL SLOWLY TAPER
OFF TO FLURRIES FROM WEST TO EAST SATURDAY AFTERNOON WITH IMPROVING
VSBY.
CIGS WILL DROP DOWN TO MVFR WITHIN THE HEAVIER SNOW SHOWERS THIS
EVENING...THEN EXPECT A TREND OF MORE WIDESPREAD MVFR CIGS WITH IFR
ACROSS HIGHER TERRAIN LATE TONIGHT THROUGH SATURDAY AS LOW LEVEL
MOISTURE DEEPENS...AND UPSLOPE FLOW INCREASES.
OUTLOOK...
SUNDAY THROUGH WEDNESDAY...VFR...WITH OCCASIONAL RESTRICTIONS TO
MVFR/IFR IN SCATTERED TO NUMEROUS SNOW SHOWERS.
&&
.MARINE...
FOLLOWING THE PASSAGE OF A WARM FRONT THIS MORNING...MODEST
SOUTHERLY WINDS WILL VEER SOUTHWESTERLY AND INCREASE SOME TODAY...
WITH THESE BRIEFLY REACHING LOW-END ADVISORY LEVELS ON LAKE
ERIE...THE UPPER NIAGARA RIVER...AND WESTERN PORTIONS OF LAKE
ONTARIO...THEN DIMINISHING AGAIN LATER ON THIS AFTERNOON AND THIS
EVENING. FOR THESE...SMALL CRAFT ADVISORIES REMAIN IN EFFECT AS
OUTLINED BELOW.
AFTER THIS...RELATIVELY QUIET CONDITIONS ARE THEN EXPECTED FOR
TONIGHT...BEFORE A COUPLE OF PASSING CLIPPER SYSTEMS BRING
ADDITIONAL ROUNDS OF ADVISORY-LEVEL SOUTHWESTERLIES DURING THE
COURSE OF THE WEEKEND...WITH THE STRONGEST OF THESE LOOKING TO
COME ON SUNDAY.
&&
.CLIMATE...
THE COLD THAT DEVELOPS NEXT WEEK IS VERY LIKELY TO LAST THROUGH THE
END OF JANUARY AND POSSIBLY INTO EARLY FEBRUARY WITH MOST DAYS
SEEING BELOW AVERAGE OR EVEN WELL BELOW AVERAGE TEMPERATURES.
THE D+11 TOOLS FROM CPC WHICH TAKE A 7 DAY RUNNING MEAN OF THE GEFS
ENSEMBLE MEAN FROM JANUARY 24-30 SHOW A VERY DEEP LONGWAVE TROUGH
OVER EASTERN NORTH AMERICA WITH A SHARP RIDGE ALONG THE WEST COAST
EXTENDING ALL THE WAY NORTH TO ALASKA AND BEYOND TO THE NORTH POLE.
TO SEE SUCH AMPLIFICATION IN A ONE WEEK AVERAGE OF GEFS MEAN 500MB
HEIGHT IS VERY IMPRESSIVE...SINCE IT IS A TIME AVERAGED PRODUCT OF
SOMETHING THAT IS ALREADY AN AVERAGE OF THE VARIOUS ENSEMBLE
MEMBERS. BOTTOM LINE...THIS SHOWS VERY GOOD AGREEMENT AMONGST GEFS
ENSEMBLE MEMBERS FOR A LONG PERIOD OF HIGHLY AMPLIFIED LONGWAVE
FLOW. THE ECMWF ENSEMBLE MEAN ALSO SHOWS A SIMILAR PATTERN.
THE PATTERN SHOWN BY THE ENSEMBLE MEAN IS A STRONG POSITIVE PNA
PATTERN...WELL KNOWN FOR DELIVERING ANY COLD AIR AVAILABLE INTO OUR
PORTION OF NORTH AMERICA. THIS LONGWAVE PATTERN ALSO SUPPORTS THE
POTENTIAL FOR CROSS POLAR FLOW...ALLOWING SIBERIAN AIR TO CROSS THE
POLES AND SPILL INTO NORTHERN CANADA. FROM THERE...THE PATTERN
SUPPORTS PIECES OF THIS COLD MOVING INTO THE NORTHERN TIER OF THE
UNITED STATES FROM THE UPPER MISSISSIPPI VALLEY EAST ACROSS THE
GREAT LAKES AND NEW ENGLAND.
THE D+11 TOOLS ALSO LOOK BACK TO FIND ANALOGS THAT CLOSELY MATCH
THIS 500MB PATTERN TO PAST EVENTS...GIVING THE 10 BEST MATCHES FOR
ANALOG DATES. A LOOK BACK AT SURFACE CONDITIONS DURING THESE ANALOG
DATES SHOW THE VAST MAJORITY OF THEM HAD SURFACE TEMPERATURES OF
15-20 DEGREES BELOW AVERAGE.
TO SUM UP...THE PATTERN STRONGLY SUPPORTS MUCH BELOW AVERAGE
TEMPERATURES MOST OF THE TIME FROM NEXT WEEK THROUGH THE END OF THE
MONTH AND POSSIBLY INTO EARLY FEBRUARY. OF COURSE WITH COLD AIR
COMES LAKE EFFECT POTENTIAL...BUT THE DETAILS WHICH DRIVE LOCATION
AND AMOUNTS ARE NOT APPARENT AT THIS TIME RANGE.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR LEZ020-
040-041.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR
LOZ042.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...HITCHCOCK
MARINE...JJR
CLIMATE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
726 AM EST FRI JAN 17 2014
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL PUSH EAST ACROSS THE REGION TODAY. WEAK
SURFACE RIDGING IS THEN EXPECTED TO BUILD BRIEFLY INTO THE AREA
TONIGHT AND EARLY ON SATURDAY. A CLIPPER SYSTEM WILL THEN RAPIDLY
SPREAD SNOW BACK INTO THE AREA SATURDAY AFTERNOON AND NIGHT.
SURFACE RIDGING WILL PUSH BACK INTO THE AREA ON SUNDAY IN THE WAKE
OF THE CLIPPER SYSTEM. ANOTHER ARCTIC COLD FRONT WILL FOLLOW ON
MONDAY BRINGING A RETURN OF VERY COLD AIR FOR THE MIDDLE OF NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BASED ON RADAR TRENDS AND CONTINUED TREND OF THE RAP...THINK
LOCALLY 2 INCHES WILL BE POSSIBLE ACROSS SOUTHWEST PORTIONS OF OUR
FA. HAVE THEREFORE OPTED TO GO WITH A QUICK ADVISORY FOR THE
CINCINNATI AREA.
PREVIOUS DISCUSSION--->
LOOKING AT THE LATEST RADAR TRENDS...PCPN MAINLY IN THE FORM OF
SNOW SHOWERS...WAS CONGEALING TOGETHER WEST AND SOUTHWEST OF THE
CWFA. THE LATEST NAM-WRF AND RAP ARE NOW INDICATING STRONGER LOW
LEVEL CONVERGENCE MOVING INTO THE WESTERN PARTS OF THE CWFA THIS
MORNING...RESULTING IN HIGHER MODEL QPF VALUES. HAVE TRENDED QPF
AMOUNTS UPWARD IN THESE AREAS...ALTHOUGH NOT AS HIGH AS THE MODELS
SUGGEST. THIS ALLOWS FOR SNOWFALL AMOUNTS TO RANGE BETWEEN 1 AND 2
INCHES IN THE WESTERN ZONES WITH UP TO AN INCH ELSEWHERE. HAVE
UPDATED THE SPS TO INCLUDE THIS NEW THINKING. WILL CONTINUE TO
MONITOR RADAR TRENDS AND MODELS SHOULD AN ADVISORY HEADLINE BE
NEEDED IF AMOUNTS LOOK TO BE HIGHER THAN CURRENTLY FORECAST.
REMAINDER OF THE DISCUSSION IS STILL GOOD BELOW.
PREVIOUS DISCUSSION--->
HAVE LEANED MORE TOWARD HIGHER RES MODELS FOR TODAYS FORECAST.
AN ARCTIC COLD FRONT WILL PUSH EAST ACROSS THE REGION THIS MORNING
INTO THE EARLY AFTERNOON HOURS. MODELS SUGGEST THAT A WEAK SFC LOW
WILL DEVELOP ALONG THIS FRONT. THIS SFC LOW WILL PROVIDE AN AXIS
OF LOW LEVEL CONVERGENCE FOR SNOW SHOWERS TO DEVELOP ON. AS A
RESULT...IT LOOKS LIKE THE ENTIRE FORECAST AREA SHOULD SEE A
PERIOD OF SNOW SHOWERS AHEAD AND ALONG THE FRONT AS IT MOVES EAST.
WARMER AIR BEING DRAWN INTO THE REGION AHEAD OF THE COLD FRONT MAY
ALLOW SOME RAIN TO BRIEFLY MIX IN OUR EASTERN ZONES. HOWEVER...THE
WET BULB EFFECT MAY PREVENT THIS FROM HAPPENING SO HAVE KEPT PTYPE
ALL SNOW AT THIS TIME. SNOW ACCUMULATION...UP TO AN INCH...WILL
OCCUR IN A SHORT PERIOD OF TIME. THIS AMOUNT...ALONG WITH REDUCED
VISIBILITIES IN SOME OF THE MODERATE TO LOCALLY HEAVY SNOW
SHOWERS...WILL POSE A TRAVEL THREAT FOR THE ENTIRE REGION TODAY.
HAVE THUS ISSUES AN SPS HIGHLIGHTING THIS THREAT. A WELL DEFINED
S/WV (VORT MAX) ALOFT WILL PUSH ACRS THE AREA THIS AFTERNOON/THIS
EVENING IN THE WAKE OF THE FRONT. THIS FEATURE...ALONG WITH
STEEPING LOW LEVEL LAPSE RATES AND SOME WEAK LOW LEVEL SPEED
CONVERGENCE SHOULD KEEP SNOW SHOWER ACTIVITY GOING SOME BEHIND THE
ARCTIC FRONT. THIS ACTIVITY...HOWEVER...SHOULD BE LIGHTER IN
NATURE WITH LITTLE ADDITIONAL ACCUMULATION EXPECTED.
TEMPERATURES WILL BE TRICKY TODAY GIVEN SOME WAA THIS MORNING
AHEAD OF THE FRONT WITH TEMPERATURES TUMBLING IN THE WAKE OF THE
FRONT. EVEN THE HIGH RES MODELS ARE HAVING A HARD TIME CAPTURING
CURRENT CONDITIONS. HIGHS SHOULD RANGE FROM THE MID 20S NW TO THE
MID 30S SE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
EMBEDDED S/WV (VORT MAX) WILL EXIT TO THE NE OF THE REGION THIS
EVENING. AS IT DOES...SNOW SHOWER ACTIVITY SHOULD WANE FROM WEST
TO EAST. WEAK SURFACE RIDGING IS THEN EXPECTED TO BUILD INTO THE
OHIO VALLEY OVERNIGHT. LOWS WILL BOTTOM OUT IN THE 10 TO 15 DEGREE
RANGE BY SATURDAY MORNING.
MODELS ARE IN DECENT AGREEMENT IN TERMS OF A CLIPPER SYSTEM TO
AFFECT OUR AREA LATER SATURDAY AFTERNOON AND NIGHT. HAVE USED A
BLEND OF THE GFS/ECMWF GIVEN BETTER SIMILARITY TO SYNOPTIC
FEATURES. SURFACE RIDGE WILL RAPIDLY MOVE EAST ON SATURDAY AS THE
CLIPPER DIVES SE FROM THE NRN PLAINS TO THE OHIO VALLEY BY
SATURDAY NIGHT. GOOD WAA/ISENTROPIC LIFT WILL ACCOMPANY THIS
SYSTEM AS IT ENTERS OUR AREA LATE SATURDAY AFTERNOON AND EVENING.
THEREAFTER...MODELS SHOW A FAIRLY RAPID WEAKENING TO THE SYSTEM AS IT
SHIFTS EAST OVERNIGHT...BECOMING ABSORBED WITH A STRONGER...LARGE
SCALE UPR LVL LOW DIGGING INTO QUEBEC. HAVE GONE WITH CATEGORICAL
POPS ALL LOCATIONS. 1 TO 2 INCHES OF SNOW LOOKS FAIRLY REASONABLE
REGION WIDE WITH PERHAPS SOME 3 INCH AMOUNTS POSSIBLE NORTH OF THE
CINCINNATI AND JUST SOUTH OF DAYTON PER LATEST MODEL RUNS. WILL
CONTINUE TO HIGHLIGHT THIS SYSTEM IN THE HWO. TEMPERATURES
SATURDAY INTO SATURDAY NIGHT WILL SHOW WARMING DUE TO WAA AHEAD OF
THE CLIPPER FOLLOWED BY A LITTLE COOL DOWN TOWARD SUNRISE SUNDAY.
ON SUNDAY...SFC RIDGING WILL MOVE INTO THE OHIO VALLEY. WE SHOULD
SEE CLOUDS SCATTERED BY AFTERNOON...ALLOWING FOR SOME SUNSHINE.
REGION WILL BE CAUGHT BETWEEN SFC RIDGE AND ANOTHER ARCTIC COLD
FRONT TO OUR NORTH AND NORTHWEST. THE PRESSURE GRADIENT BETWEEN
THESE TWO FEATURES WILL RESULT IN BREEZY CONDITIONS BUT WILL ALSO
ALLOW FOR SOME WARMING.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A COLD FRONT WILL DROP DOWN INTO THE FA ON MONDAY. MOISTURE IS
LIMITED WITH THIS FEATURE AND THEREFORE LIMITED SNOWFALL CHANCES
AT THIS TIME TO A SLIGHT CHANCE. MUCH COLDER AIR WILL BE USHERED
INTO THE AREA HOWEVER FOR THE REMAINDER OF THE LONG TERM TIME
FRAME.
THE LOWEST TEMPERATURES ARE EXPECTED TO OCCUR WEDNESDAY MORNING AND
THURSDAY MORNING. WIND CHILL VALUES WEDNESDAY MORNING WILL BE NEAR
WIND CHILL ADVISORY CRITERIA.
SOME LAKE EFFECT SNOW SHOWERS WILL BE POSSIBLE ACROSS PORTIONS OF
THE FA MONDAY NIGHT INTO TUESDAY EVENING. AFTER THIS TIME WENT WITH
DRY CONDITIONS ACROSS THE FA. THE GFS IS HINTING AT A DISTURBANCE
MOVING THROUGH THE FA WEDNESDAY NIGHT INTO THURSDAY MORNING HOWEVER
THERE HAS BEEN QUITE A BIT OF RUN TO RUN DIFFERENCES DURING THIS
TIME AND THE ECMWF HAS DRY CONDITIONS DURING THAT TIME. DUE TO THIS
HAVE LEFT WEDNESDAY NIGHT INTO THURSDAY DRY AT THIS POINT AND WILL
CONTINUE TO EVALUATE WITH ADDITIONAL MODEL RUNS.
&&
.AVIATION /13Z FRIDAY THROUGH TUESDAY/...
THE PRIMARY CONCERN FOR AVIATION TODAY WILL BE AN AREA OF SNOW
SHOWERS...FORECAST TO MOVE THROUGH THE TAF SITES OVER THE NEXT
6-9 HOURS. UPSTREAM CONDITIONS SUGGEST THAT THESE SNOW SHOWERS
WILL BE ALMOST CERTAIN TO BRING IFR CONDITIONS TO THE TAF
SITES...WITH VISIBILITIES BEING BRIEFLY AND SHARPLY REDUCED.
CEILINGS WILL ALSO GET INTO THE IFR RANGE...AND SOME BRIEF LIFR
CONDITIONS MAY BE POSSIBLE IF A VERY HEAVY SNOW SHOWER HAPPENS TO
PASS OVER AN AIRPORT.
FROM LATE MORNING THROUGH AFTERNOON...WINDS WILL SHIFT TO THE WEST
AS A FRONT PASSES THROUGH THE AREA. THESE WINDS WILL GUST TO AROUND
20 KNOTS. SOME SNOW SHOWERS WILL CONTINUE...THOUGH GENERALLY OF A
LIGHTER VARIETY...WITH PREVAILING CONDITIONS LIKELY TO REMAIN IN
THE MVFR RANGE.
ALTHOUGH SOME BREAKS IN THE CLOUDS WILL BE POSSIBLE DURING THE
EVENING...ESPECIALLY AT THE CINCINNATI TAF SITES...MVFR CEILINGS
ARE EXPECTED TO PERSIST THROUGH THE OVERNIGHT HOURS AND INTO
SATURDAY MORNING.
OUTLOOK...MVFR CONDITIONS WILL REMAIN OCCASIONALLY POSSIBLE
THROUGH SUNDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
OHZ070>072-077>080.
KY...WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
KYZ089>099.
IN...WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
INZ066-073>075-080.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...JGL
SHORT TERM...HICKMAN
LONG TERM...NOVAK
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
645 AM EST FRI JAN 17 2014
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL PUSH EAST ACROSS THE REGION TODAY. WEAK
SURFACE RIDGING IS THEN EXPECTED TO BUILD BRIEFLY INTO THE AREA
TONIGHT AND EARLY ON SATURDAY. A CLIPPER SYSTEM WILL THEN RAPIDLY
SPREAD SNOW BACK INTO THE AREA SATURDAY AFTERNOON AND NIGHT.
SURFACE RIDGING WILL PUSH BACK INTO THE AREA ON SUNDAY IN THE WAKE
OF THE CLIPPER SYSTEM. ANOTHER ARCTIC COLD FRONT WILL FOLLOW ON
MONDAY BRINGING A RETURN OF VERY COLD AIR FOR THE MIDDLE OF NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOOKING AT THE LATEST RADAR TRENDS...PCPN MAINLY IN THE FORM OF
SNOW SHOWERS...WAS CONGEALING TOGETHER WEST AND SOUTHWEST OF THE
CWFA. THE LATEST NAM-WRF AND RAP ARE NOW INDICATING STRONGER LOW
LEVEL CONVERGENCE MOVING INTO THE WESTERN PARTS OF THE CWFA THIS
MORNING...RESULTING IN HIGHER MODEL QPF VALUES. HAVE TRENDED QPF
AMOUNTS UPWARD IN THESE AREAS...ALTHOUGH NOT AS HIGH AS THE MODELS
SUGGEST. THIS ALLOWS FOR SNOWFALL AMOUNTS TO RANGE BETWEEN 1 AND 2
INCHES IN THE WESTERN ZONES WITH UP TO AN INCH ELSEWHERE. HAVE
UPDATED THE SPS TO INCLUDE THIS NEW THINKING. WILL CONTINUE TO
MONITOR RADAR TRENDS AND MODELS SHOULD AN ADVISORY HEADLINE BE
NEEDED IF AMOUNTS LOOK TO BE HIGHER THAN CURRENTLY FORECAST.
REMAINDER OF THE DISCUSSION IS STILL GOOD BELOW.
PREVIOUS DISCUSSION--->
HAVE LEANED MORE TOWARD HIGHER RES MODELS FOR TODAYS FORECAST.
AN ARCTIC COLD FRONT WILL PUSH EAST ACROSS THE REGION THIS MORNING
INTO THE EARLY AFTERNOON HOURS. MODELS SUGGEST THAT A WEAK SFC LOW
WILL DEVELOP ALONG THIS FRONT. THIS SFC LOW WILL PROVIDE AN AXIS
OF LOW LEVEL CONVERGENCE FOR SNOW SHOWERS TO DEVELOP ON. AS A
RESULT...IT LOOKS LIKE THE ENTIRE FORECAST AREA SHOULD SEE A
PERIOD OF SNOW SHOWERS AHEAD AND ALONG THE FRONT AS IT MOVES EAST.
WARMER AIR BEING DRAWN INTO THE REGION AHEAD OF THE COLD FRONT MAY
ALLOW SOME RAIN TO BRIEFLY MIX IN OUR EASTERN ZONES. HOWEVER...THE
WET BULB EFFECT MAY PREVENT THIS FROM HAPPENING SO HAVE KEPT PTYPE
ALL SNOW AT THIS TIME. SNOW ACCUMULATION...UP TO AN INCH...WILL
OCCUR IN A SHORT PERIOD OF TIME. THIS AMOUNT...ALONG WITH REDUCED
VISIBILITIES IN SOME OF THE MODERATE TO LOCALLY HEAVY SNOW
SHOWERS...WILL POSE A TRAVEL THREAT FOR THE ENTIRE REGION TODAY.
HAVE THUS ISSUES AN SPS HIGHLIGHTING THIS THREAT. A WELL DEFINED
S/WV (VORT MAX) ALOFT WILL PUSH ACRS THE AREA THIS AFTERNOON/THIS
EVENING IN THE WAKE OF THE FRONT. THIS FEATURE...ALONG WITH
STEEPING LOW LEVEL LAPSE RATES AND SOME WEAK LOW LEVEL SPEED
CONVERGENCE SHOULD KEEP SNOW SHOWER ACTIVITY GOING SOME BEHIND THE
ARCTIC FRONT. THIS ACTIVITY...HOWEVER...SHOULD BE LIGHTER IN
NATURE WITH LITTLE ADDITIONAL ACCUMULATION EXPECTED.
TEMPERATURES WILL BE TRICKY TODAY GIVEN SOME WAA THIS MORNING
AHEAD OF THE FRONT WITH TEMPERATURES TUMBLING IN THE WAKE OF THE
FRONT. EVEN THE HIGH RES MODELS ARE HAVING A HARD TIME CAPTURING
CURRENT CONDITIONS. HIGHS SHOULD RANGE FROM THE MID 20S NW TO THE
MID 30S SE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
EMBEDDED S/WV (VORT MAX) WILL EXIT TO THE NE OF THE REGION THIS
EVENING. AS IT DOES...SNOW SHOWER ACTIVITY SHOULD WANE FROM WEST
TO EAST. WEAK SURFACE RIDGING IS THEN EXPECTED TO BUILD INTO THE
OHIO VALLEY OVERNIGHT. LOWS WILL BOTTOM OUT IN THE 10 TO 15 DEGREE
RANGE BY SATURDAY MORNING.
MODELS ARE IN DECENT AGREEMENT IN TERMS OF A CLIPPER SYSTEM TO
AFFECT OUR AREA LATER SATURDAY AFTERNOON AND NIGHT. HAVE USED A
BLEND OF THE GFS/ECMWF GIVEN BETTER SIMILARITY TO SYNOPTIC
FEATURES. SURFACE RIDGE WILL RAPIDLY MOVE EAST ON SATURDAY AS THE
CLIPPER DIVES SE FROM THE NRN PLAINS TO THE OHIO VALLEY BY
SATURDAY NIGHT. GOOD WAA/ISENTROPIC LIFT WILL ACCOMPANY THIS
SYSTEM AS IT ENTERS OUR AREA LATE SATURDAY AFTERNOON AND EVENING.
THEREAFTER...MODELS SHOW A FAIRLY RAPID WEAKENING TO THE SYSTEM AS IT
SHIFTS EAST OVERNIGHT...BECOMING ABSORBED WITH A STRONGER...LARGE
SCALE UPR LVL LOW DIGGING INTO QUEBEC. HAVE GONE WITH CATEGORICAL
POPS ALL LOCATIONS. 1 TO 2 INCHES OF SNOW LOOKS FAIRLY REASONABLE
REGION WIDE WITH PERHAPS SOME 3 INCH AMOUNTS POSSIBLE NORTH OF THE
CINCINNATI AND JUST SOUTH OF DAYTON PER LATEST MODEL RUNS. WILL
CONTINUE TO HIGHLIGHT THIS SYSTEM IN THE HWO. TEMPERATURES
SATURDAY INTO SATURDAY NIGHT WILL SHOW WARMING DUE TO WAA AHEAD OF
THE CLIPPER FOLLOWED BY A LITTLE COOL DOWN TOWARD SUNRISE SUNDAY.
ON SUNDAY...SFC RIDGING WILL MOVE INTO THE OHIO VALLEY. WE SHOULD
SEE CLOUDS SCATTERED BY AFTERNOON...ALLOWING FOR SOME SUNSHINE.
REGION WILL BE CAUGHT BETWEEN SFC RIDGE AND ANOTHER ARCTIC COLD
FRONT TO OUR NORTH AND NORTHWEST. THE PRESSURE GRADIENT BETWEEN
THESE TWO FEATURES WILL RESULT IN BREEZY CONDITIONS BUT WILL ALSO
ALLOW FOR SOME WARMING.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A COLD FRONT WILL DROP DOWN INTO THE FA ON MONDAY. MOISTURE IS
LIMITED WITH THIS FEATURE AND THEREFORE LIMITED SNOWFALL CHANCES
AT THIS TIME TO A SLIGHT CHANCE. MUCH COLDER AIR WILL BE USHERED
INTO THE AREA HOWEVER FOR THE REMAINDER OF THE LONG TERM TIME
FRAME.
THE LOWEST TEMPERATURES ARE EXPECTED TO OCCUR WEDNESDAY MORNING AND
THURSDAY MORNING. WIND CHILL VALUES WEDNESDAY MORNING WILL BE NEAR
WIND CHILL ADVISORY CRITERIA.
SOME LAKE EFFECT SNOW SHOWERS WILL BE POSSIBLE ACROSS PORTIONS OF
THE FA MONDAY NIGHT INTO TUESDAY EVENING. AFTER THIS TIME WENT WITH
DRY CONDITIONS ACROSS THE FA. THE GFS IS HINTING AT A DISTURBANCE
MOVING THROUGH THE FA WEDNESDAY NIGHT INTO THURSDAY MORNING HOWEVER
THERE HAS BEEN QUITE A BIT OF RUN TO RUN DIFFERENCES DURING THIS
TIME AND THE ECMWF HAS DRY CONDITIONS DURING THAT TIME. DUE TO THIS
HAVE LEFT WEDNESDAY NIGHT INTO THURSDAY DRY AT THIS POINT AND WILL
CONTINUE TO EVALUATE WITH ADDITIONAL MODEL RUNS.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
THE PRIMARY CONCERN FOR AVIATION TODAY WILL BE AN AREA OF SNOW
SHOWERS...FORECAST TO MOVE THROUGH THE TAF SITES OVER THE NEXT
6-9 HOURS. UPSTREAM CONDITIONS SUGGEST THAT THESE SNOW SHOWERS
WILL BE ALMOST CERTAIN TO BRING IFR CONDITIONS TO THE TAF
SITES...WITH VISIBILITIES BEING BRIEFLY AND SHARPLY REDUCED.
CEILINGS WILL ALSO GET INTO THE IFR RANGE...AND SOME BRIEF LIFR
CONDITIONS MAY BE POSSIBLE IF A VERY HEAVY SNOW SHOWER HAPPENS TO
PASS OVER AN AIRPORT.
FROM LATE MORNING THROUGH AFTERNOON...WINDS WILL SHIFT TO THE WEST
AS A FRONT PASSES THROUGH THE AREA. THESE WINDS WILL GUST TO AROUND
20 KNOTS. SOME SNOW SHOWERS WILL CONTINUE...THOUGH GENERALLY OF A
LIGHTER VARIETY...WITH PREVAILING CONDITIONS LIKELY TO REMAIN IN
THE MVFR RANGE.
ALTHOUGH SOME BREAKS IN THE CLOUDS WILL BE POSSIBLE DURING THE
EVENING...ESPECIALLY AT THE CINCINNATI TAF SITES...MVFR CEILINGS
ARE EXPECTED TO PERSIST THROUGH THE OVERNIGHT HOURS AND INTO
SATURDAY MORNING.
OUTLOOK...MVFR CONDITIONS WILL REMAIN OCCASIONALLY POSSIBLE
THROUGH SUNDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...HICKMAN
SHORT TERM...HICKMAN
LONG TERM...NOVAK
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
528 AM EST FRI JAN 17 2014
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL PUSH EAST ACROSS THE REGION TODAY. WEAK
SURFACE RIDGING IS THEN EXPECTED TO BUILD BRIEFLY INTO THE AREA
TONIGHT AND EARLY ON SATURDAY. A CLIPPER SYSTEM WILL THEN RAPIDLY
SPREAD SNOW BACK INTO THE AREA SATURDAY AFTERNOON AND NIGHT.
SURFACE RIDGING WILL PUSH BACK INTO THE AREA ON SUNDAY IN THE WAKE
OF THE CLIPPER SYSTEM. ANOTHER ARCTIC COLD FRONT WILL FOLLOW ON
MONDAY BRINGING A RETURN OF VERY COLD AIR FOR THE MIDDLE OF NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOOKING AT THE LATEST RADAR TRENDS...PCPN MAINLY IN THE FORM OF
SNOW SHOWERS...WAS CONGEALING TOGETHER WEST AND SOUTHWEST OF THE
CWFA. THE LATEST NAM-WRF AND RAP ARE NOW INDICATING STRONGER LOW
LEVEL CONVERGENCE MOVING INTO THE WESTERN PARTS OF THE CWFA THIS
MORNING...RESULTING IN HIGHER MODEL QPF VALUES. HAVE TRENDED QPF
AMOUNTS UPWARD IN THESE AREAS...ALTHOUGH NOT AS HIGH AS THE MODELS
SUGGEST. THIS ALLOWS FOR SNOWFALL AMOUNTS TO RANGE BETWEEN 1 AND 2
INCHES IN THE WESTERN ZONES WITH UP TO AN INCH ELSEWHERE. HAVE
UPDATED THE SPS TO INCLUDE THIS NEW THINKING. WILL CONTINUE TO
MONITOR RADAR TRENDS AND MODELS SHOULD AN ADVISORY HEADLINE BE
NEEDED IF AMOUNTS LOOK TO BE HIGHER THAN CURRENTLY FORECAST.
REMAINDER OF THE DISCUSSION IS STILL GOOD BELOW.
PREVIOUS DISCUSSION--->
HAVE LEANED MORE TOWARD HIGHER RES MODELS FOR TODAYS FORECAST.
AN ARCTIC COLD FRONT WILL PUSH EAST ACROSS THE REGION THIS MORNING
INTO THE EARLY AFTERNOON HOURS. MODELS SUGGEST THAT A WEAK SFC LOW
WILL DEVELOP ALONG THIS FRONT. THIS SFC LOW WILL PROVIDE AN AXIS
OF LOW LEVEL CONVERGENCE FOR SNOW SHOWERS TO DEVELOP ON. AS A
RESULT...IT LOOKS LIKE THE ENTIRE FORECAST AREA SHOULD SEE A
PERIOD OF SNOW SHOWERS AHEAD AND ALONG THE FRONT AS IT MOVES EAST.
WARMER AIR BEING DRAWN INTO THE REGION AHEAD OF THE COLD FRONT MAY
ALLOW SOME RAIN TO BRIEFLY MIX IN OUR EASTERN ZONES. HOWEVER...THE
WET BULB EFFECT MAY PREVENT THIS FROM HAPPENING SO HAVE KEPT PTYPE
ALL SNOW AT THIS TIME. SNOW ACCUMULATION...UP TO AN INCH...WILL
OCCUR IN A SHORT PERIOD OF TIME. THIS AMOUNT...ALONG WITH REDUCED
VISIBILITIES IN SOME OF THE MODERATE TO LOCALLY HEAVY SNOW
SHOWERS...WILL POSE A TRAVEL THREAT FOR THE ENTIRE REGION TODAY.
HAVE THUS ISSUES AN SPS HIGHLIGHTING THIS THREAT. A WELL DEFINED
S/WV (VORT MAX) ALOFT WILL PUSH ACRS THE AREA THIS AFTERNOON/THIS
EVENING IN THE WAKE OF THE FRONT. THIS FEATURE...ALONG WITH
STEEPING LOW LEVEL LAPSE RATES AND SOME WEAK LOW LEVEL SPEED
CONVERGENCE SHOULD KEEP SNOW SHOWER ACTIVITY GOING SOME BEHIND THE
ARCTIC FRONT. THIS ACTIVITY...HOWEVER...SHOULD BE LIGHTER IN
NATURE WITH LITTLE ADDITIONAL ACCUMULATION EXPECTED.
TEMPERATURES WILL BE TRICKY TODAY GIVEN SOME WAA THIS MORNING
AHEAD OF THE FRONT WITH TEMPERATURES TUMBLING IN THE WAKE OF THE
FRONT. EVEN THE HIGH RES MODELS ARE HAVING A HARD TIME CAPTURING
CURRENT CONDITIONS. HIGHS SHOULD RANGE FROM THE MID 20S NW TO THE
MID 30S SE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
EMBEDDED S/WV (VORT MAX) WILL EXIT TO THE NE OF THE REGION THIS
EVENING. AS IT DOES...SNOW SHOWER ACTIVITY SHOULD WANE FROM WEST
TO EAST. WEAK SURFACE RIDGING IS THEN EXPECTED TO BUILD INTO THE
OHIO VALLEY OVERNIGHT. LOWS WILL BOTTOM OUT IN THE 10 TO 15 DEGREE
RANGE BY SATURDAY MORNING.
MODELS ARE IN DECENT AGREEMENT IN TERMS OF A CLIPPER SYSTEM TO
AFFECT OUR AREA LATER SATURDAY AFTERNOON AND NIGHT. HAVE USED A
BLEND OF THE GFS/ECMWF GIVEN BETTER SIMILARITY TO SYNOPTIC
FEATURES. SURFACE RIDGE WILL RAPIDLY MOVE EAST ON SATURDAY AS THE
CLIPPER DIVES SE FROM THE NRN PLAINS TO THE OHIO VALLEY BY
SATURDAY NIGHT. GOOD WAA/ISENTROPIC LIFT WILL ACCOMPANY THIS
SYSTEM AS IT ENTERS OUR AREA LATE SATURDAY AFTERNOON AND EVENING.
THEREAFTER...MODELS SHOW A FAIRLY RAPID WEAKENING TO THE SYSTEM AS IT
SHIFTS EAST OVERNIGHT...BECOMING ABSORBED WITH A STRONGER...LARGE
SCALE UPR LVL LOW DIGGING INTO QUEBEC. HAVE GONE WITH CATEGORICAL
POPS ALL LOCATIONS. 1 TO 2 INCHES OF SNOW LOOKS FAIRLY REASONABLE
REGION WIDE WITH PERHAPS SOME 3 INCH AMOUNTS POSSIBLE NORTH OF THE
CINCINNATI AND JUST SOUTH OF DAYTON PER LATEST MODEL RUNS. WILL
CONTINUE TO HIGHLIGHT THIS SYSTEM IN THE HWO. TEMPERATURES
SATURDAY INTO SATURDAY NIGHT WILL SHOW WARMING DUE TO WAA AHEAD OF
THE CLIPPER FOLLOWED BY A LITTLE COOL DOWN TOWARD SUNRISE SUNDAY.
ON SUNDAY...SFC RIDGING WILL MOVE INTO THE OHIO VALLEY. WE SHOULD
SEE CLOUDS SCATTERED BY AFTERNOON...ALLOWING FOR SOME SUNSHINE.
REGION WILL BE CAUGHT BETWEEN SFC RIDGE AND ANOTHER ARCTIC COLD
FRONT TO OUR NORTH AND NORTHWEST. THE PRESSURE GRADIENT BETWEEN
THESE TWO FEATURES WILL RESULT IN BREEZY CONDITIONS BUT WILL ALSO
ALLOW FOR SOME WARMING.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A COLD FRONT WILL DROP DOWN INTO THE FA ON MONDAY. MOISTURE IS
LIMITED WITH THIS FEATURE AND THEREFORE LIMITED SNOWFALL CHANCES
AT THIS TIME TO A SLIGHT CHANCE. MUCH COLDER AIR WILL BE USHERED
INTO THE AREA HOWEVER FOR THE REMAINDER OF THE LONG TERM TIME
FRAME.
THE LOWEST TEMPERATURES ARE EXPECTED TO OCCUR WEDNESDAY MORNING AND
THURSDAY MORNING. WIND CHILL VALUES WEDNESDAY MORNING WILL BE NEAR
WIND CHILL ADVISORY CRITERIA.
SOME LAKE EFFECT SNOW SHOWERS WILL BE POSSIBLE ACROSS PORTIONS OF
THE FA MONDAY NIGHT INTO TUESDAY EVENING. AFTER THIS TIME WENT WITH
DRY CONDITIONS ACROSS THE FA. THE GFS IS HINTING AT A DISTURBANCE
MOVING THROUGH THE FA WEDNESDAY NIGHT INTO THURSDAY MORNING HOWEVER
THERE HAS BEEN QUITE A BIT OF RUN TO RUN DIFFERENCES DURING THIS
TIME AND THE ECMWF HAS DRY CONDITIONS DURING THAT TIME. DUE TO THIS
HAVE LEFT WEDNESDAY NIGHT INTO THURSDAY DRY AT THIS POINT AND WILL
CONTINUE TO EVALUATE WITH ADDITIONAL MODEL RUNS.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS ARE SPREADING INTO THE TAF SITES...WITH SOME MVFR
CEILINGS EXPECTED FOR THE NEXT FEW HOURS. HOWEVER...RESTRICTIONS
TO AVIATION CONDITIONS WILL ARRIVE AGAIN ON FRIDAY MORNING. SNOW
WILL MOVE INTO THE AREA FROM WEST TO EAST...PROVIDING PREVAILING
MVFR CONDITIONS...WITH SOME HEAVIER SNOW SHOWERS DROPPING
VISIBILITIES TO IFR.
AS THIS SNOW MOVES THROUGH THE AREA...WINDS WILL SHIFT TO THE
WEST...AND PICK UP IN INTENSITY (WITH GUSTS OF AROUND 20 KNOTS).
CONDITIONS APPEAR FAVORABLE FOR CONTINUING SNOW SHOWERS GOING INTO
THE AFTERNOON...WITH MVFR CEILINGS AND VISIBILITIES.
BY EVENING...THE CEILINGS ARE EXPECTED TO SCATTER OUT...AS WINDS
GRADUALLY DIMINISH IN INTENSITY.
OUTLOOK...MVFR CONDITIONS WILL REMAIN OCCASIONALLY POSSIBLE
THROUGH SUNDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...HICKMAN
SHORT TERM...HICKMAN
LONG TERM...NOVAK
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS PORTLAND OR
1015 AM PST FRI JAN 17 2014
.SYNOPSIS...A STRONG RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE
REGION TODAY. A WEAK TROUGH ALOFT WILL MOVE ACROSS THE RIDGE THIS
WEEKEND...DROPPING A WEAK FRONT DOWN INTO THE NW CORNER OF OREGON
SATURDAY AND SUNDAY. THE RIDGE OF HIGH PRESSURE ALOFT WILL REBUILD
EARLY NEXT WEEK.
&&
.MORNING UPDATE...ONLY A FEW MINOR CHANGES NEEDED THIS MORNING.
OBSERVATIONS INDICATE THAT VISIBILITIES REMAIN AT OR BELOW ONE HALF
MILE ACROSS THE VALLEYS THIS MORNING. THEREFORE EXTENDED THE DENSE
FOG ADVISORY THROUGH NOON TODAY AND ADJUSTED GRIDS TO INCREASE CLOUD
COVER ACROSS THE NORTHERN WILLAMETTE VALLEY FOR THE NEXT SEVERAL
HOURS. THE REMAINDER OF THE FORECAST REMAINS VALID AND EXPECT TODAY
TO BE SIMILAR TO YESTERDAY...WITH COOL TEMPERATURES WITH FOG AND
CLOUDS IN THE INTERIOR VALLEYS...AND CLEAR SKIES WITH WARMER
TEMPERATURES AT THE COAST AND HIGHER ELEVATIONS.
ALSO ISSUED AN AIR STAGNATION ADVISORY FOR THE CLARK COUNTY AND LOWER
COLUMBIA AND I-5 CORRIDOR ZONES IN SOUTHWEST WASHINGTON. THIS AND THE
EXISTING AIR STAGNATION ADVISORY FOR THE CENTRAL AND SOUTHERN
WILLAMETTE VALLEY WILL BE IN EFFECT THROUGH NEXT FRIDAY MORNING.
OPTED NOT TO INCLUDE METRO PORTLAND AREA AT THIS TIME BECAUSE EAST
WINDS THROUGH THE GORGE WILL LIKELY BE SUFFICENT TO PROVIDE MIXING TO
PREVENT STAGNANT AIR THROUGH THE NEXT FEW DAYS. CULLEN
.LONG TERM...MONDAY THROUGH THROUGH THURSDAY. FEW CHANGES IN THE
EXTENDED PERIOD. AFTER THE WEAK FRONT PASSES THROUGH THE AREA ON
SUNDAY...HIGH PRESSURE WILL QUICKLY REBUILD OVER THE EASTERN PACIFIC
AND PACIFIC NORTHWEST. THIS RIDGE WILL CONTINUE TO DOMINATE OUR
WEATHER PATTERN AND BY TUESDAY THE UPPER RIDGE WILL AMPLIFY WITH THE
RIDGE AXIS LOCATED ALONG OR NEAR THE WEST COAST. BOTH THE 12Z ECMWF
AND GFS DEPICT A SHORTWAVE IMPULSE THAT SPLITS NEAR 140W EARLY NEXT
WEEK...WITH A CLOSED LOW MOVING INTO THE CENTRAL CA COAST AND AN
UPPER LEVEL TROUGH WELL TO OUR NORTH OVER THE TOP OF THE RIDGE. UNTIL
THE FORECAST MODELS GIVE A STRONG REASON TO BELIEVE OTHERWISE...IT
APPEARS THIS RIDGE WILL CONTINUE REMAIN IN PLACE AND KEEP THE
FORECAST AREA DRY THROUGH AT LEAST LATE NEXT WEEK.
A RETURN OF DAILY FOG AND LOW CLOUDS IS LIKELY FOR THE VALLEY
LOCATIONS...THOUGH THE NORTH WILLAMETTE VALLEY MAY BE MORE LIKELY TO
SEE LESS FOG AND/OR BREAK OUT EARLIER DURING THE MIDDLE OF NEXT WEEK
DEPENDING ON EAST WINDS DEVELOPING THROUGH THE COLUMBIA RIVER GORGE.
HIGH TEMPERATURES LOOK TO BE A FEW DEGREES ABOVE SEASONAL NORMALS
THROUGH THE EXTENDED WHILE LOWS WILL BE NEAR NORMS. CULLEN
&&
.AVIATION...VFR ACROSS REGION...EXCEPT IN THE LOWER
COLUMBIA/COWLITZ AND WILLAMETTE VALLEY WHERE IFR FOG/STRATUS
PERSISTS. ALREADY SEEING TOPS OF THE CLOUDS IN THE WEST HILLS OF
PORTLAND SO TOPS AROUND 1000 FT. EXPECT A SIMILAR SITUATION TO
THURSDAY WITH SOME IMPROVEMENT LATE THIS MORNING AND EARLY
AFTERNOON...AND THEN AREAS OF CLEARING IN THE AFTERNOON. THEN A
RETURN TO LIFR CONDITIONS THIS EVENING AND OVERNIGHT. EAST WINDS
WILL PROVIDE SOME CLEARING AROUND KPDX AND KTTD THIS
AFTERNOON BUT WILL BE MAINLY ABOVE THE FOG LAYER. HRRR SUGGESTS
EAST WINDS PUNCH THROUGH TO THE SURFACE AT KTTD AFTER 0Z
TODAY...SO KEPT THE LIGHT WNW WIND IN PLACE FOR THE NORTH VALLEY
SITES FOR THE DAY. EAST WINDS MAY SNEAK OVER TO KHIO LATER TODAY.
WITH A STRONGER GRADIENT EXPECT THE NEAR GORGE CLEAR OUT A BIT FOR A
BIT LONGER THURSDAY.
KPDX AND APPROACHES...EXPECT DENSE FOG AND LOW CLOUDS THROUGH THE
MORNING AS MOST OF THE EAST FLOW IS JUST ABOVE THE FOG LAYER.
STILL EXPECT TO SEE SOME EAST WIND FILTERING INTO KPDX OPS AREA
AT TIMES AFTER 21Z. SHOULD SEE A REPEAT OF THU...BUT HOPEFULLY A BIT
MORE CLEARING ON EASTERN APPROACHES. THOUGH STRATUS LIKELY TO
PERSIST OVER CLARK COUNTY AND FROM WILSONVILLE SOUTHWARD. KMD
&&
.MARINE...LITTLE CHANGE. HIGH PRES REMAINS OVER PAC NW...WITH
OFFSHORE WINDS 10 TO 15 KT. WINDS EASE BACK SAT AND SUN. SEAS
HOLDING AT 4 TO 5 FT TODAY. SWELL WILL INCREASE THIS WEEKEND...
WITH 10 TO 11 FT AGAIN LATER SAT NIGHT AND SUN. EXPECT SIMILAR
CONDITIONS NEXT WEEK WITH OCCASIONAL WEAK FRONTS PASSING THROUGH
THAT WILL BUMP SWELLS UP ABOVE 10 FT AT TIMES...NOTABLY LATER
MONDAY AND AGAIN LATER THURSDAY. KMD
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...AIR STAGNATION ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
FRIDAY FOR LOWER COLUMBIA.
AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY FOR CENTRAL
WILLAMETTE VALLEY-SOUTH WILLAMETTE VALLEY.
DENSE FOG ADVISORY UNTIL NOON PST TODAY FOR CENTRAL WILLAMETTE
VALLEY-GREATER PORTLAND METRO AREA-SOUTH WILLAMETTE VALLEY.
WA...AIR STAGNATION ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
FRIDAY FOR GREATER VANCOUVER AREA-I-5 CORRIDOR IN COWLITZ
COUNTY.
DENSE FOG ADVISORY UNTIL NOON PST TODAY FOR GREATER VANCOUVER
AREA.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT..
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
912 PM PST THU JAN 16 2014
.SYNOPSIS...HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH
SATURDAY MORNING...ALLOWING VALLEY FOG AND LOW CLOUDS TO PERSIST
WHILE MILD AND SUNNY CONDITIONS WILL DOMINATE THE WEATHER FOR COASTAL
AND MOUNTAIN LOCATIONS. A WEAK FRONT ARRIVING LATE SATURDAY INTO
SUNDAY WILL BRING A SMALL CHANCE FOR LIGHT RAIN TO THE COAST.
OTHERWISE...HIGH PRESSURE IS EXPECTED TO DOMINATE THE WEATHER AGAIN
NEXT WEEK AND BRING MORE OF SAME WEATHER OF LATE.
&&
.SHORT TERM...DENSE FOG IS BEGINNING TO FILL IN THE WILLAMETTE VALLEY
TONIGHT AND THE ONLY CHANGE MADE TO THE FORECAST WAS TO ISSUE A DENSE
FOG ADVISORY FOR THE WILLAMETTE VALLEY TONIGHT THROUGH THURSDAY
MORNING. THE FOG IS NOT WIDESPREAD YET...BUT IS LOCATED AROUND THE
MAJOR HIGHWAYS AND TRAVELERS WILL NEED TO EXERCISE EXTRA CAUTION.
EASTERLY WINDS MAY RESULT IN FOG CLEARING THAN ANTICIPATED...BUT
THINK THE STRONG INVERSION WILL BE DIFFICULT TO DISRUPT. HARTLEY
PREVIOUS DISCUSSION FOLLOWS...A SUBSTANTIAL SUBSIDENCE INVERSION LIES
BETWEEN 1000 AND 3000 FEET TODAY...RESULTING IN TEMPERATURES WARMING
AT LEAST 20 DEGREES AS ONE GOES UP BETWEEN THESE TWO ELEVATIONS.
WHILE RAWS STATIONS HAVE A WARM BIAS ON LOW WIND...SUNNY DAYS...60S
CERTAINLY ABOUND ACROSS MOST OF THE HIGHER HILLS IN THE COAST RANGE
AND CASCADE FOOTHILLS.
VISIBLE SATELLITE IMAGERY INDICATES LOW CLOUDS ARE HANGING TOUGH
ACROSS THE SOUTHERN HALF OF THE WILLAMETTE VALLEY...NORTH OF I84 IN
THE PORTLAND METRO AREA AND ALONG THE KELSO TO CASTLE ROCK CORRIDOR
THIS AFTERNOON. IT IS CERTAINLY INTERESTING THAT MCMINNVILLE AND
HILLSBORO CLEARED BEFORE KTTD AND KPDX. THE HRRR INDICATES LOW LEVEL
WINDS WILL REMAIN NORTHWESTERLY ALONG THE COLUMBIA RIVER NEAR KPDX
AND KTTD UNTIL LATE TONIGHT SO THESE AREAS WILL BE HARD PRESSED TO
GO COMPLETELY CLEAR THIS AFTERNOON BASED ON VISIBLE SATELLITE
TRENDS. WHAT CLEARING DOES OCCUR SHOULD BE SHORT LIVED AS CLOUDS AND
FOG FILL BACK IN QUICKLY THIS EVENING.
THE CURRENT KDLS-KTTD PRESSURE GRADIENT IS HOVERING NEAR 4MB AND
SHOULD RAMP UP LATER TONIGHT TO APPROXIMATELY 6MB...PERHAPS 7MB.
BECAUSE THE KDLS-KTTD PRESSURE GRADIENT SHOULD ONLY BE STRONGER
FRIDAY MANY OF THE SAME AREAS WILL CLEAR FRIDAY AFTERNOON...PLUS
THOSE THAT WERE OH SO CLOSE TODAY INCLUDING CLARK COUNTY AND PERHAPS
SALEM. EXPECT TEMPERATURES TO BE SIMILAR FRIDAY...BUT A TOUCH COOLER
NEAR THE CENTRAL OREGON COAST WHERE LOW LEVEL WINDS WILL TURN A
LITTLE MORE SOUTHERLY.
OTHERWISE...A SHORTWAVE TROUGH STILL LOOKS ON TRACK TO SLIDE EASTWARD
WELL NORTH OF OUR CWA LATE SATURDAY. THIS WILL DRAG A DYING FRONT
INTO OUR COASTAL WATERS WITH A SLIGHT CHANCE THAT MEASURABLE RAIN
WILL OCCUR ALONG THE NORTHWEST OREGON COAST AND FAR SOUTHWEST
WASHINGTON. HOWEVER...DPROG/DT CONTINUES TO SUGGEST THIS IS LESS AND
LESS LIKELY. RIDGING WILL THEN BEGIN TO BUILD NORTHWARD ACROSS THE
NORTHEAST PACIFIC ON SUNDAY. THE REMNANTS OF THE AFOREMENTIONED
FRONT WILL LIFT NORTHWARD AND ACT AS A WARM FRONT...BRINGING ANOTHER
SMALL CHANCE FOR LIGHT PRECIPITATION SUNDAY...BUT AGAIN MODELS SEEM
TO BE TRENDING DRIER WITH THIS SYSTEM SO POPS WERE KEPT GENERALLY
SLIGHT CHANCE OR LESS. /NEUMAN
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY. FEW CHANGES IN THE
EXTENDED PERIOD. AFTER THE WEAK FRONT PASSES THROUGH THE AREA ON
SUNDAY...HIGH PRESSURE WILL QUICKLY REBUILD OVER THE EASTERN PACIFIC
AND PACIFIC NORTHWEST. THIS RIDGE WILL CONTINUE TO DOMINATE OUR
WEATHER PATTERN AND BY TUESDAY THE UPPER RIDGE WILL AMPLIFY WITH THE
RIDGE AXIS LOCATED ALONG OR NEAR THE WEST COAST. BOTH THE 12Z ECMWF
AND GFS DEPICT A SHORTWAVE IMPULSE THAT SPLITS NEAR 140W EARLY NEXT
WEEK...WITH A CLOSED LOW MOVING INTO THE CENTRAL CA COAST AND AN
UPPER LEVEL TROUGH WELL TO OUR NORTH OVER THE TOP OF THE RIDGE.
UNTIL THE FORECAST MODELS GIVE A STRONG REASON TO BELIEVE
OTHERWISE...IT APPEARS THIS RIDGE WILL CONTINUE REMAIN IN PLACE AND
KEEP THE FORECAST AREA DRY THROUGH AT LEAST LATE NEXT WEEK.
A RETURN OF DAILY FOG AND LOW CLOUDS IS LIKELY FOR THE VALLEY
LOCATIONS...THOUGH THE NORTH WILLAMETTE VALLEY MAY BE MORE LIKELY TO
SEE LESS FOG AND/OR BREAK OUT EARLIER DURING THE MIDDLE OF NEXT WEEK
DEPENDING ON EAST WINDS DEVELOPING THROUGH THE COLUMBIA RIVER GORGE.
HIGH TEMPERATURES LOOK TO BE A FEW DEGREES ABOVE SEASONAL NORMALS
THROUGH THE EXTENDED WHILE LOWS WILL BE NEAR NORMS. CULLEN
&&
.AVIATION...AFTER SOME CLOUD BREAKS THIS AFTERNOON...WIDESPREAD
LIFR VALLEY FOG HAS RETURNED THIS EVENING. OFFSHORE GRADIENT
STRENGTHENS OVERNIGHT AND INTO FRIDAY...WHICH WILL ALLOW NORTH
VALLEY CLEARING AND POSSIBLY A BIT MORE ON FRIDAY. VFR CONDITIONS
PREVAIL ALONG THE COAST AND MOUNTAINS.
KPDX AND APPROACHES...LIFR FOG CONTINUES THROUGH AT LEAST 18Z-20Z
FRIDAY MORNING. OFFSHORE GRADIENT WILL BEGIN WORKING ITS WAY
TOWARDS EASTERN APPROACHES WHICH SHOULD HELP TO ERODE CLOUDS OR
AT LEAST LIFT CLOUDS AND VSBYS WITH GOOD CLEARING FOR TOMORROW
AFTERNOON. KMD/27
&&
.MARINE...HIGH PRES REMAINS OVER THE PAC NW THROUGH THE WEEKEND.
THIS WILL MAINTAIN WEAK PRES GRADIENTS AND E WINDS 15 KT OR
LESS...THOUGH EXPECT SOME GUSTS TO 20 KT FROM TIME TO
TIME...MAINLY ON FRI. SEAS CONTINUE TO SUBSIDE.
A WEAK FRONT WILL PUSH ACROSS REGION THIS WEEKEND...BUT NOT MUCH
IN WAY OF WIND. WILL SEE SEVERAL SWELL TRAINS OF 10 TO 12 FT
ARRIVING THIS WEEKEND INTO EARLY NEXT WEEK. ROCKEY.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...AIR STAGNATION ADVISORY UNTIL 10 AM PST TUESDAY FOR CENTRAL
WILLAMETTE VALLEY-SOUTH WILLAMETTE VALLEY.
DENSE FOG ADVISORY UNTIL 9 AM PST FRIDAY FOR CENTRAL WILLAMETTE
VALLEY-GREATER PORTLAND METRO AREA-SOUTH WILLAMETTE VALLEY.
WA...DENSE FOG ADVISORY UNTIL 9 AM PST FRIDAY FOR GREATER VANCOUVER
AREA.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT..
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1137 AM CST FRI JAN 17 2014
.DISCUSSION...
18Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
DRY AND COOL AIR MASS MAINTAINING REGIONAL VFR CONDITIONS THROUGH
THE PERIOD. SKY CLEAR WITH A MODEST NORTH-NORTHEAST BREEZE TODAY
BECOMING VRB03KTS/CALM OVERNIGHT...WAKE UP FROM SOUTHEAST-SOUTH
BY LATE SATURDAY MORNING. 31
&&
.PREV DISCUSSION... /ISSUED 1031 AM CST FRI JAN 17 2014/
UPDATE...
SEE MORNING UPDATE AND FIRE WEATHER DISCUSSION.
DISCUSSION...
12Z SOUNDINGS SUPPORT TEMPS IN THE MID AND UPPER 60S BUT WEAK COLD
AIR ADVECTION IN THE WAKE OF AN EARLY MORNING COLD FRONT WILL
SHAVE A FEW DEGREES FROM SOUNDINGS VALUES. SURFACE DEW POINTS ARE
CONSIDERABLY DRIER THAN MODELS SUGGEST SO HAVE EDITED THE DEW PT
GRIDS TO REFLECT CURRENT LOWER VALUES. THIS WILL HAVE
IMPLICATIONS FOR FIRE WEATHER AND SEE THE FIRE WEATHER DISCUSSION
FOR MORE INFO. MADE SOME MINOR TWEAKS HERE AND THERE BUT THE
REASONING FROM THE PREVIOUS FCST IS STILL ON TARGET. 43
FIRE WEATHER...
SURFACE DEW PTS ARE IN THE TEENS AND COULD DROP FURTHER WITH
MIXING THIS AFTERNOON. RUC13 DATA SUGGEST DEW PTS IN THE SINGLE
DIGITS THIS AFTN. RH VALUES WILL STRUGGLE TO REACH 25 PERCENT
TODAY WHICH IS CRITICALLY DRY. KHGX VWP SHOWS WINDS OF 20 TO 20
KNOTS IN THE 1000-3000 FOOT LAYER. FEEL SOME OF THIS WIND ENERGY
WILL MIX TO THE SURFACE THIS AFTN SO BUMPED WINDS UP A LITTLE.
WIND SPEEDS WILL REMAIN BELOW RED FLAG CRITERIA BUT CONSIDERING
THE DRY ANTECEDENT CONDITIONS...VERY LOW RH VALUES AND MODERATE
WINDS...FEEL THERE IS STILL AN ELEVATED THREAT FOR DANGEROUS FIRE
WEATHER CONDS. 43
PREV DISCUSSION... /ISSUED 456 AM CST FRI JAN 17 2014/
DISCUSSION...
SEE AVIATION FOR 12Z TAF ISSUANCE.
AVIATION...
CURRENT TAF PACKAGE LOOKS ON TRACK AND HAVE MADE ONLY MINOR
CHANGES. FRONT HAS CONTINUED TO MOVE OFFSHORE WITH SECONDARY COLD
FRONT MOVING SOUTH FROM NORTH TEXAS. NORTH WINDS AND VFR CONDITIONS
ARE EXPECTED THIS AFTERNOON. WINDS WILL THEN RELAX THIS EVENING AS
SURFACE HIGH PRESSURE SHIFTS OVERHEAD. 23
PREV DISCUSSION... /ISSUED 444 AM CST FRI JAN 17 2014/
DISCUSSION...
DRY AIR IS SLOWLY SPREADING OVER THE AREA IN THE WAKE OF A WEAK
PACIFIC COLD FRONTAL BOUNDARY. RAINS OVER THE GULF WATERS SHOULD
SHIFT SOUTHWARD AS FRONT MOVES OFF THE COAST AND ACROSS THE GULF
WATERS EARLY THIS MORNING. SKIES WILL START OFF WITH SOME HIGH
CLOUDS BUT AS THE UPPER TROUGH ROTATES AWAY TO THE EAST EXPECTING
MORE SUBSIDENCE AND THE HIGH CLOUDS TO DISSIPATE AND DEPART THIS
AFTERNOON. AFTER HIGHS SHOULD ONLY REACH THE LOWER 60S TODAY AFTER
YESTERDAYS WARM UPPER 60S TO AROUND 70. SFC RIDGE AXIS WILL BE
OVERHEAD SATURDAY MORNING AND TEMPERATURES WILL DROP TO 29-31
DEGREES OVER THE NORTHEASTERN AREAS BUT IT LOOKS LIKE THE METRO
AREA AND AROUND CLL SHOULD STAY ABOVE FREEZING. THE RIDGE MOVES
OFF QUICKLY TO THE EAST SATURDAY AND MOISTURE AND WARMTH MAKES A
COMEBACK. WARM FRONT SHOULD REACH UP INTO THE COASTAL WATERS AND
MAY JUST REACH THE COAST SATURDAY NIGHT SO WITH THE UPPER JET
TRAVERSING THE STATE AND SOME WEAK LIFT MAY HAVE ISO-SCT SHOWERS
OVER THE GULF WATERS BUT SETX SHOULD STAY DRY. REINFORCING PACIFIC
COLD FRONT CROSSES SETX SATURDAY NIGHT WASHING OUT VERY QUICKLY
AND SE-S WIND RESUME SUNDAY AFTERNOON/NIGHT. WARMER WEATHER
RETURNS MONDAY BEFORE THE FRONT SWINGS DOWN MONDAY NIGHT. FOR NOW
WILL ONLY SHOW SOME POPS IN THE SOUTHWEST AREAS FOR EARLY TUESDAY
MORNING AS MOISTURE RETURN DOESN`T PEAK UNTIL EARLY TUESDAY. SOME
POSSIBILITY OF SEA FOG BUT MAYBE MORE OF THE 2-5 MILE VARIETY WITH
THE SOUTHWEST TRAJECTORIES. STRONGER HIGH PRESSURE DROPPING SOUTH
TUESDAY PUSHES THE FRONT THROUGH AND SHOULD MAKE FOR A COOL PERIOD
FROM TUE-THU (WARMING UP THU). UPPER PATTERN BRINGS A DECENT S/W
OUT OF THE PACIFIC ON SUBTROPICAL JET AND MAY LEAD TO BETTER RAIN
CHANCES BY FRIDAY/SATURDAY.
45
MARINE...
WIDESPREAD CONVECTION IS ONGOING THIS MORNING OVER THE
OFFSHORE WATERS. THE DIFFUSE FRONTAL BOUNDARY WILL CONTINUE TO PUSH
OFFSHORE THIS MORNING WHICH SHOULD HELP BRING THE PRECIPITATION TO
AN END. BEHIND THE FRONT WINDS WILL REACH SCEC CRITERIA OVER THE
OFFSHORE WATERS WITH SLIGHTLY WEAKER WINDS OVER THE COOLER SHELF
WATERS. WINDS WILL FALL BELOW SCEC CRITERIA BY THIS EVENING. SURFACE
HIGH PRESSURE BEHIND THE FRONT WILL QUICKLY MOVE OFF TO THE EAST
FRIDAY NIGHT INTO SATURDAY MORNING ALLOWING ONSHORE FLOW TO RESUME.
LIGHT TO MODERATE ONSHORE WINDS WITH 2 TO 4 FT SEAS WILL PERSIST
UNTIL TUESDAY WHEN THE NEXT COLD FRONT IS FORECASTED TO MOVE OVER
THE WATERS. ADVISORIES WILL LIKELY BE NEEDED AFTER THE FRONTAL
PASSAGE. 23
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 35 66 45 70 52 / 0 10 10 10 10
HOUSTON (IAH) 37 65 46 72 52 / 0 0 10 10 10
GALVESTON (GLS) 47 63 54 67 56 / 0 0 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL NOON CST TODAY FOR THE
FOLLOWING ZONES: MATAGORDA BAY...WATERS FROM FREEPORT TO
THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL NOON CST TODAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO
60 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 5 PM CST THIS
AFTERNOON FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO
THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
HIGH ISLAND TO FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...43
AVIATION/MARINE...31
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1031 AM CST FRI JAN 17 2014
.UPDATE...
SEE MORNING UPDATE AND FIRE WEATHER DISCUSSION.
&&
.DISCUSSION...
12Z SOUNDINGS SUPPORT TEMPS IN THE MID AND UPPER 60S BUT WEAK COLD
AIR ADVECTION IN THE WAKE OF AN EARLY MORNING COLD FRONT WILL
SHAVE A FEW DEGREES FROM SOUNDINGS VALUES. SURFACE DEW POINTS ARE
CONSIDERABLY DRIER THAN MODELS SUGGEST SO HAVE EDITED THE DEW PT
GRIDS TO REFLECT CURRENT LOWER VALUES. THIS WILL HAVE
IMPLICATIONS FOR FIRE WEATHER AND SEE THE FIRE WEATHER DISCUSSION
FOR MORE INFO. MADE SOME MINOR TWEAKS HERE AND THERE BUT THE
REASONING FROM THE PREVIOUS FCST IS STILL ON TARGET. 43
&&
.FIRE WEATHER...
SURFACE DEW PTS ARE IN THE TEENS AND COULD DROP FURTHER WITH
MIXING THIS AFTERNOON. RUC13 DATA SUGGEST DEW PTS IN THE SINGLE
DIGITS THIS AFTN. RH VALUES WILL STRUGGLE TO REACH 25 PERCENT
TODAY WHICH IS CRITICALLY DRY. KHGX VWP SHOWS WINDS OF 20 TO 20
KNOTS IN THE 1000-3000 FOOT LAYER. FEEL SOME OF THIS WIND ENERGY
WILL MIX TO THE SURFACE THIS AFTN SO BUMPED WINDS UP A LITTLE.
WIND SPEEDS WILL REMAIN BELOW RED FLAG CRITERIA BUT CONSIDERING
THE DRY ANTECEDENT CONDITIONS...VERY LOW RH VALUES AND MODERATE
WINDS...FEEL THERE IS STILL AN ELEVATED THREAT FOR DANGEROUS FIRE
WEATHER CONDS. 43
&&
.PREV DISCUSSION... /ISSUED 456 AM CST FRI JAN 17 2014/
DISCUSSION...
SEE AVIATION FOR 12Z TAF ISSUANCE.
AVIATION...
CURRENT TAF PACKAGE LOOKS ON TRACK AND HAVE MADE ONLY MINOR
CHANGES. FRONT HAS CONTINUED TO MOVE OFFSHORE WITH SECONDARY COLD
FRONT MOVING SOUTH FROM NORTH TEXAS. NORTH WINDS AND VFR CONDITIONS
ARE EXPECTED THIS AFTERNOON. WINDS WILL THEN RELAX THIS EVENING AS
SURFACE HIGH PRESSURE SHIFTS OVERHEAD. 23
PREV DISCUSSION... /ISSUED 444 AM CST FRI JAN 17 2014/
DISCUSSION...
DRY AIR IS SLOWLY SPREADING OVER THE AREA IN THE WAKE OF A WEAK
PACIFIC COLD FRONTAL BOUNDARY. RAINS OVER THE GULF WATERS SHOULD
SHIFT SOUTHWARD AS FRONT MOVES OFF THE COAST AND ACROSS THE GULF
WATERS EARLY THIS MORNING. SKIES WILL START OFF WITH SOME HIGH
CLOUDS BUT AS THE UPPER TROUGH ROTATES AWAY TO THE EAST EXPECTING
MORE SUBSIDENCE AND THE HIGH CLOUDS TO DISSIPATE AND DEPART THIS
AFTERNOON. AFTER HIGHS SHOULD ONLY REACH THE LOWER 60S TODAY AFTER
YESTERDAYS WARM UPPER 60S TO AROUND 70. SFC RIDGE AXIS WILL BE
OVERHEAD SATURDAY MORNING AND TEMPERATURES WILL DROP TO 29-31
DEGREES OVER THE NORTHEASTERN AREAS BUT IT LOOKS LIKE THE METRO
AREA AND AROUND CLL SHOULD STAY ABOVE FREEZING. THE RIDGE MOVES
OFF QUICKLY TO THE EAST SATURDAY AND MOISTURE AND WARMTH MAKES A
COMEBACK. WARM FRONT SHOULD REACH UP INTO THE COASTAL WATERS AND
MAY JUST REACH THE COAST SATURDAY NIGHT SO WITH THE UPPER JET
TRAVERSING THE STATE AND SOME WEAK LIFT MAY HAVE ISO-SCT SHOWERS
OVER THE GULF WATERS BUT SETX SHOULD STAY DRY. REINFORCING PACIFIC
COLD FRONT CROSSES SETX SATURDAY NIGHT WASHING OUT VERY QUICKLY
AND SE-S WIND RESUME SUNDAY AFTERNOON/NIGHT. WARMER WEATHER
RETURNS MONDAY BEFORE THE FRONT SWINGS DOWN MONDAY NIGHT. FOR NOW
WILL ONLY SHOW SOME POPS IN THE SOUTHWEST AREAS FOR EARLY TUESDAY
MORNING AS MOISTURE RETURN DOESN`T PEAK UNTIL EARLY TUESDAY. SOME
POSSIBILITY OF SEA FOG BUT MAYBE MORE OF THE 2-5 MILE VARIETY WITH
THE SOUTHWEST TRAJECTORIES. STRONGER HIGH PRESSURE DROPPING SOUTH
TUESDAY PUSHES THE FRONT THROUGH AND SHOULD MAKE FOR A COOL PERIOD
FROM TUE-THU (WARMING UP THU). UPPER PATTERN BRINGS A DECENT S/W
OUT OF THE PACIFIC ON SUBTROPICAL JET AND MAY LEAD TO BETTER RAIN
CHANCES BY FRIDAY/SATURDAY.
45
MARINE...
WIDESPREAD CONVECTION IS ONGOING THIS MORNING OVER THE
OFFSHORE WATERS. THE DIFFUSE FRONTAL BOUNDARY WILL CONTINUE TO PUSH
OFFSHORE THIS MORNING WHICH SHOULD HELP BRING THE PRECIPITATION TO
AN END. BEHIND THE FRONT WINDS WILL REACH SCEC CRITERIA OVER THE
OFFSHORE WATERS WITH SLIGHTLY WEAKER WINDS OVER THE COOLER SHELF
WATERS. WINDS WILL FALL BELOW SCEC CRITERIA BY THIS EVENING. SURFACE
HIGH PRESSURE BEHIND THE FRONT WILL QUICKLY MOVE OFF TO THE EAST
FRIDAY NIGHT INTO SATURDAY MORNING ALLOWING ONSHORE FLOW TO RESUME.
LIGHT TO MODERATE ONSHORE WINDS WITH 2 TO 4 FT SEAS WILL PERSIST
UNTIL TUESDAY WHEN THE NEXT COLD FRONT IS FORECASTED TO MOVE OVER
THE WATERS. ADVISORIES WILL LIKELY BE NEEDED AFTER THE FRONTAL
PASSAGE. 23
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 60 35 66 45 70 / 0 0 10 10 10
HOUSTON (IAH) 63 37 65 46 72 / 0 0 0 10 10
GALVESTON (GLS) 62 47 63 54 67 / 0 0 0 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL NOON CST TODAY FOR THE
FOLLOWING ZONES: MATAGORDA BAY...WATERS FROM FREEPORT TO
THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL NOON CST TODAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO
60 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 5 PM CST THIS
AFTERNOON FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO
THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
HIGH ISLAND TO FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...43
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1108 AM CST FRI JAN 17 2014
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND SATURDAY
ISSUED AT 417 AM CST FRI JAN 17 2014
SURFACE AND UPPER SYSTEM PULLING OUT OF AREA EARLY
THIS MORNING. DRIER AIR WORKING INTO WESTERN HALF OF STATE WITH
CEILINGS IMPROVING...SNOW ENDING. LIGHT SNOW CONTINUES OVER MUCH
OF CWA ATTM WITH PERSISTENT BANDING FEATURE NOW LOCATED FROM GRB
INTO ISW. THOUGH RADAR RETURNS LOOK MORE OMINOUS...SURFACE REPORTS
HAVE VISBYS MAINLY 2 MILES OR ABOVE. PREVIOUS FORECAST OF INCH
OVERNIGHT LOOKS TO BE HOLDING OUTSIDE OF LES REGION. MODELS SHOW
THIS TREND CONTINUING WITH BAND TAKING ON A NE TO SW ORIENTATION
AND EXITING REGION THIS AFTERNOON. GIVEN CURRENT TRENDS...LESS
THAN AN INCH OF FURTHER ACCUMULATION EXPECTED. QUESTION FOR THE DAY
IS TEMPERATURES...WITH CURRENT WARMING TREND OVER THE NORTHERN CWA
AS TEMPERATURES ARE CURRENTLY IN THE UPPER TEENS TO LOW 20S. HAVE
TRENDED HIGH TEMPS TOWARDS RAP MODEL BRINGING TODAYS MAX TEMPS UP...WITH
SOME LIKELY BEING REACHED EARLY THIS MORNING.
SURFACE RIDGE MOVES OVER STATE TONIGHT. CLEARING AND LIGHT
WINDS...WILL ALLOW TEMPS TO DROP SIGNIFICANTLY BEFORE MORE CLOUDS
MOVE IN AND WAA BEGINS DURING THE SECOND HALF OF NIGHT. TONIGHTS TEMPS
WILL LIKELY NEED ANOTHER LOOK AS MODEL TRENDS THIS RUN HAVE BEEN
TO PUSH NEXT CLIPPER SYSTEM TRACK FURTHER WEST. MAIN CHANGE THIS
FORECAST WAS TO SLOW TIMING OF PCPN INTO CENTRAL WI AND CUT BACK
ON HOW FAR NORTH AND EAST IT WILL REACH ON SAT.
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY
ISSUED AT 417 AM CST FRI JAN 17 2014
UPPER LEVEL FLOW WAS FORECAST TO BE FROM THE NORTH-NORTHWEST DURING
THIS PART OF THE FORECAST...WITH A WEST COAST RIDGE AND A TROUGH
AXIS OVER...OR A LITTLE BIT TO THE EAST OF...WISCONSIN. TIMING OF
CLIPPER SYSTEMS IN THIS FLOW REGIME WILL BE A CHALLENGE FOR THIS
WEEKEND AND THE UPCOMING WEEK.
THERE IS SOME LAKE EFFECT SNOW SHOWER POTENTIAL IN NORTH CENTRAL
WISCONSIN AS COLD AIR PASSES OVER LAKE SUPERIOR...BUT GLERL ICE
CONCENTRATION GRAPHICS SHOWED LITTLE OPEN WATER NORTH AND WEST OF
THE KEWEENAW PENINSULA. HAVE KEPT POPS ON THE LOW SIDE IN NORTH
CENTRAL WISCONSIN BECAUSE OF THIS. MUCH OF NORTHERN LAKE MICHIGAN
REMAINS OPEN SO THERE IS SOME CHANCE FOR LAKE EFFECT SNOW SHOWERS
IN EASTERN WISCONSIN IF WINDS BECOME FAVORABLE IN THAT AREA...BUT
THERE DOES NOT APPEAR TO BE ANYTHING WORTH MORE THAN A LOW END
CHANCE POP AT TIMES.
HAVE A CHANCE FOR SNOW IN THE NORTH ON SATURDAY NIGHT...ASSOCIATED
WITH A DEPARTING CLIPPER. THERE WERE STILL ENOUGH DIFFERENCES
AMONG THE MODELS IN THEIR LOCATION AND TIMING OF QPF MONDAY...SO
LEFT POPS MAINLY IN THE SLIGHT CHANCE CATEGORY. OTHER THAN THESE
SYSTEMS...SLIGHT CHANCE OR LOW END CHANCE POPS DUE TO POSSIBLE
LAKE EFFECT SNOW SHOWERS.
TEMPERATURES SHOULD BE ABOVE NORMAL ON SUNDAY BEFORE THE ARCTIC
FRONT PASSES THROUGH THE AREA. AFTER THAT...EXPECT MUCH COLDER
THAN NORMAL TEMPERATURES. HIGHS ON TUESDAY AND WEDNESDAY WILL BE
CLOSER TO NORMAL LOWS FOR THIS TIME OF YEAR.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1107 AM CST FRI JAN 17 2014
SYSTEM THAT MOVED INTO THE AREA YDA HAS BEEN SLOW TO CLEAR...SO WL
NEED TO KEEP LOWER CLDS AND LGT SNOW LONGER THAN IN PREV TAFS.
SYSTEM THAT APPEARED TO BE HEADING FOR THE AREA TOMORROW NOW LOOKS
LIKE IT WL TRACK FARTHER SW.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......MG
AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
615 AM CST FRI JAN 17 2014
UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND SATURDAY
ISSUED AT 417 AM CST FRI JAN 17 2014
SURFACE AND UPPER SYSTEM PULLING OUT OF AREA EARLY
THIS MORNING. DRIER AIR WORKING INTO WESTERN HALF OF STATE WITH
CEILINGS IMPROVING...SNOW ENDING. LIGHT SNOW CONTINUES OVER MUCH
OF CWA ATTM WITH PERSISTENT BANDING FEATURE NOW LOCATED FROM GRB
INTO ISW. THOUGH RADAR RETURNS LOOK MORE OMINOUS...SURFACE REPORTS
HAVE VISBYS MAINLY 2 MILES OR ABOVE. PREVIOUS FORECAST OF INCH
OVERNIGHT LOOKS TO BE HOLDING OUTSIDE OF LES REGION. MODELS SHOW
THIS TREND CONTINUING WITH BAND TAKING ON A NE TO SW ORIENTATION
AND EXITING REGION THIS AFTERNOON. GIVEN CURRENT TRENDS...LESS
THAN AN INCH OF FURTHER ACCUMULATION EXPECTED. QUESTION FOR THE DAY
IS TEMPERATURES...WITH CURRENT WARMING TREND OVER THE NORTHERN CWA
AS TEMPERATURES ARE CURRENTLY IN THE UPPER TEENS TO LOW 20S. HAVE
TRENDED HIGH TEMPS TOWARDS RAP MODEL BRINGING TODAYS MAX TEMPS UP...WITH
SOME LIKELY BEING REACHED EARLY THIS MORNING.
SURFACE RIDGE MOVES OVER STATE TONIGHT. CLEARING AND LIGHT
WINDS...WILL ALLOW TEMPS TO DROP SIGNIFICANTLY BEFORE MORE CLOUDS
MOVE IN AND WAA BEGINS DURING THE SECOND HALF OF NIGHT. TONIGHTS TEMPS
WILL LIKELY NEED ANOTHER LOOK AS MODEL TRENDS THIS RUN HAVE BEEN
TO PUSH NEXT CLIPPER SYSTEM TRACK FURTHER WEST. MAIN CHANGE THIS
FORECAST WAS TO SLOW TIMING OF PCPN INTO CENTRAL WI AND CUT BACK
ON HOW FAR NORTH AND EAST IT WILL REACH ON SAT.
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY
ISSUED AT 417 AM CST FRI JAN 17 2014
UPPER LEVEL FLOW WAS FORECAST TO BE FROM THE NORTH-NORTHWEST DURING
THIS PART OF THE FORECAST...WITH A WEST COAST RIDGE AND A TROUGH
AXIS OVER...OR A LITTLE BIT TO THE EAST OF...WISCONSIN. TIMING OF
CLIPPER SYSTEMS IN THIS FLOW REGIME WILL BE A CHALLENGE FOR THIS
WEEKEND AND THE UPCOMING WEEK.
THERE IS SOME LAKE EFFECT SNOW SHOWER POTENTIAL IN NORTH CENTRAL
WISCONSIN AS COLD AIR PASSES OVER LAKE SUPERIOR...BUT GLERL ICE
CONCENTRATION GRAPHICS SHOWED LITTLE OPEN WATER NORTH AND WEST OF
THE KEWEENAW PENINSULA. HAVE KEPT POPS ON THE LOW SIDE IN NORTH
CENTRAL WISCONSIN BECAUSE OF THIS. MUCH OF NORTHERN LAKE MICHIGAN
REMAINS OPEN SO THERE IS SOME CHANCE FOR LAKE EFFECT SNOW SHOWERS
IN EASTERN WISCONSIN IF WINDS BECOME FAVORABLE IN THAT AREA...BUT
THERE DOES NOT APPEAR TO BE ANYTHING WORTH MORE THAN A LOW END
CHANCE POP AT TIMES.
HAVE A CHANCE FOR SNOW IN THE NORTH ON SATURDAY NIGHT...ASSOCIATED
WITH A DEPARTING CLIPPER. THERE WERE STILL ENOUGH DIFFERENCES
AMONG THE MODELS IN THEIR LOCATION AND TIMING OF QPF MONDAY...SO
LEFT POPS MAINLY IN THE SLIGHT CHANCE CATEGORY. OTHER THAN THESE
SYSTEMS...SLIGHT CHANCE OR LOW END CHANCE POPS DUE TO POSSIBLE
LAKE EFFECT SNOW SHOWERS.
TEMPERATURES SHOULD BE ABOVE NORMAL ON SUNDAY BEFORE THE ARCTIC
FRONT PASSES THROUGH THE AREA. AFTER THAT...EXPECT MUCH COLDER
THAN NORMAL TEMPERATURES. HIGHS ON TUESDAY AND WEDNESDAY WILL BE
CLOSER TO NORMAL LOWS FOR THIS TIME OF YEAR.
&&
.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 543 AM CST FRI JAN 17 2014
LIGHT SNOW WILL END FROM NORTHWEST TO SOUTHEAST ACROSS THE REGION
TODAY AS LOW PRESSURE PULLS OUT AND DRIER AIR AND HIGH PRESSURE
MOVES IN. THE MORE PERSISTENT SHOWERS THIS MORNING WILL BE OVER
EAST CENTRAL WISCONSIN. MVFR CIGS/VISBYS WITH SHOWERS EXPECTED.
GUSTY NORTH WINDS EXPECTED BY AFTERNOON AS LOW PULLS EAST. VFR
CONDITIONS EXPECTED BY LATE IN THE DAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......MG
AVIATION.......TE
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND SATURDAY
ISSUED AT 417 AM CST FRI JAN 17 2014
SURFACE AND UPPER SYSTEM PULLING OUT OF AREA EARLY
THIS MORNING. DRIER AIR WORKING INTO WESTERN HALF OF STATE WITH
CEILINGS IMPROVING...SNOW ENDING. LIGHT SNOW CONTINUES OVER MUCH
OF CWA ATTM WITH PERSISTENT BANDING FEATURE NOW LOCATED FROM GRB
INTO ISW. THOUGH RADAR RETURNS LOOK MORE OMINOUS...SURFACE REPORTS
HAVE VISBYS MAINLY 2 MILES OR ABOVE. PREVIOUS FORECAST OF INCH
OVERNIGHT LOOKS TO BE HOLDING OUTSIDE OF LES REGION. MODELS SHOW
THIS TREND CONTINUING WITH BAND TAKING ON A NE TO SW ORIENTATION
AND EXITING REGION THIS AFTERNOON. GIVEN CURRENT TRENDS...LESS
THAN AN INCH OF FURTHER ACCUMULATION EXPECTED. QUESTION FOR THE DAY
IS TEMPERATURES...WITH CURRENT WARMING TREND OVER THE NORTHERN CWA
AS TEMPERATURES ARE CURRENTLY IN THE UPPER TEENS TO LOW 20S. HAVE
TRENDED HIGH TEMPS TOWARDS RAP MODEL BRINGING TODAYS MAX TEMPS UP...WITH
SOME LIKELY BEING REACHED EARLY THIS MORNING.
SURFACE RIDGE MOVES OVER STATE TONIGHT. CLEARING AND LIGHT
WINDS...WILL ALLOW TEMPS TO DROP SIGNIFICANTLY BEFORE MORE CLOUDS
MOVE IN AND WAA BEGINS DURING THE SECOND HALF OF NIGHT. TONIGHTS TEMPS
WILL LIKELY NEED ANOTHER LOOK AS MODEL TRENDS THIS RUN HAVE BEEN
TO PUSH NEXT CLIPPER SYSTEM TRACK FURTHER WEST. MAIN CHANGE THIS
FORECAST WAS TO SLOW TIMING OF PCPN INTO CENTRAL WI AND CUT BACK
ON HOW FAR NORTH AND EAST IT WILL REACH ON SAT.
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY
ISSUED AT 417 AM CST FRI JAN 17 2014
UPPER LEVEL FLOW WAS FORECAST TO BE FROM THE NORTH-NORTHWEST DURING
THIS PART OF THE FORECAST...WITH A WEST COAST RIDGE AND A TROUGH
AXIS OVER...OR A LITTLE BIT TO THE EAST OF...WISCONSIN. TIMING OF
CLIPPER SYSTEMS IN THIS FLOW REGIME WILL BE A CHALLENGE FOR THIS
WEEKEND AND THE UPCOMING WEEK.
THERE IS SOME LAKE EFFECT SNOW SHOWER POTENTIAL IN NORTH CENTRAL
WISCONSIN AS COLD AIR PASSES OVER LAKE SUPERIOR...BUT GLERL ICE
CONCENTRATION GRAPHICS SHOWED LITTLE OPEN WATER NORTH AND WEST OF
THE KEWEENAW PENINSULA. HAVE KEPT POPS ON THE LOW SIDE IN NORTH
CENTRAL WISCONSIN BECAUSE OF THIS. MUCH OF NORTHERN LAKE MICHIGAN
REMAINS OPEN SO THERE IS SOME CHANCE FOR LAKE EFFECT SNOW SHOWERS
IN EASTERN WISCONSIN IF WINDS BECOME FAVORABLE IN THAT AREA...BUT
THERE DOES NOT APPEAR TO BE ANYTHING WORTH MORE THAN A LOW END
CHANCE POP AT TIMES.
HAVE A CHANCE FOR SNOW IN THE NORTH ON SATURDAY NIGHT...ASSOCIATED
WITH A DEPARTING CLIPPER. THERE WERE STILL ENOUGH DIFFERENCES
AMONG THE MODELS IN THEIR LOCATION AND TIMING OF QPF MONDAY...SO
LEFT POPS MAINLY IN THE SLIGHT CHANCE CATEGORY. OTHER THAN THESE
SYSTEMS...SLIGHT CHANCE OR LOW END CHANCE POPS DUE TO POSSIBLE
LAKE EFFECT SNOW SHOWERS.
TEMPERATURES SHOULD BE ABOVE NORMAL ON SUNDAY BEFORE THE ARCTIC
FRONT PASSES THROUGH THE AREA. AFTER THAT...EXPECT MUCH COLDER
THAN NORMAL TEMPERATURES. HIGHS ON TUESDAY AND WEDNESDAY WILL BE
CLOSER TO NORMAL LOWS FOR THIS TIME OF YEAR.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1102 PM CST THU JAN 16 2014
LARGE UPPER TROUGH WILL REMAIN SETTLED OVER THE GREAT
LAKES REGION TONIGHT INTO FRIDAY BEFORE PULLING EAST FRIDAY LATE.
A SURFACE LOW CENTERED REMAIN NEARLY STATIONARY OVER NORTHERN LAKE
MICHIGAN. A SURFACE TROUGH EXTENDED BACK TOWARD NORTHERN
WISCONSIN FROM THIS LOW. WHILE LIGHT SNOW WITH MVFR CIGS WILL
CONTINUE UNDER THE UPPER TROUGH...MORE WIDESPREAD MVFR CIGS AND
VSBYS WITH ISOLATED IFR CONDITIONS CAN BE EXPECTED ALONG THIS
SURFACE TROUGH AS IT PIVOTS SOUTH OVERNIGHT. MVFR CONDITIONS
LIKELY TO CONTINUE FOR MOST OF FRIDAY WITH SOME IMPROVEMENT TO VFR
CONDITIONS LATE IN THE DAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......MG
AVIATION.......
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
340 AM CST FRI JAN 17 2014
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 340 AM CST FRI JAN 17 2014
MAIN FORECAST CONCERN IN THE SHORT TERM WILL BE LIGHT SNOW CHANCES
THIS MORNING...AND THEN ACCUMULATING SNOW LIKELY AGAIN LATER
TONIGHT THROUGH SATURDAY.
WATER VAPOR/RAP 500MB ANALYSIS/SURFACE OBSERVATIONS SHOW A CLOSED
MID-LEVEL CYCLONIC CIRCULATION AND SURFACE LOW OVER NORTHERN LOWER
MI WITH LIGHT DEFORMATION SNOW ROTATING INTO ALL THE WAY BACK INTO
OUR FORECAST AREA. WINDS STILL A BIT BRISK ACROSS THE FORECAST
AREA...GENERALLY IN THE 10-20 MPH WITH SOME GUSTS AROUND 25 MPH YET
ACROSS THE OPEN AREAS OF SOUTHEAST MN/NORTHEAST IA. MEANWHILE...
TEMPERATURES AT 2 AM WERE IN THE SINGLE DIGITS ABOVE ZERO WHILE WIND
CHILLS WERE IN THE SINGLE DIGITS AND TEENS BELOW ZERO. A WIND CHILL
ADVISORY IS IN EFFECT UNTIL 11 AM THIS MORNING ACROSS PORTIONS OF
NORTHEAST IA AND SOUTHEAST MN WHERE WIND CHILLS WILL BE TOUCHING
CRITERIA IN THE 15 BELOW TO 25 BELOW ZERO RANGE.
PLAN ON AREAS OF LIGHT SNOW TO CONTINUE ROTATING SOUTH AND EAST
ACROSS THE AREA EARLY ON THIS MORNING...EXITING EAST BY LATER IN THE
MORNING AS THE LOW OVER NORTHERN MI PUSHES INTO SOUTHEAST ONTARIO
AND A NARROW RIDGE OF HIGH PRESSURE PUSHES IN FROM THE PLAINS. THIS
RIDGE WILL ALSO AID IN CLEARING THE SKIES FROM WEST TO EAST LATE
THIS MORNING THROUGH THE AFTERNOON HOURS. OTHERWISE...LOOK FOR
CHILLY TEMPERATURES TODAY WITH HIGHS ONLY IN THE SINGLE DIGITS AND
TEENS ABOVE ZERO.
FOR TONIGHT...LOOK FOR THE RIDGE OF HIGH PRESSURE TO PASS OVER AND
EAST OF THE REGION THIS EVENING...WHILE A VIGOROUS MID-LEVEL
CYCLONIC CIRCULATION AND SURFACE LOW DROPS SOUTHEAST OUT OF ALBERTA
INTO CENTRAL MN BY 12Z. THIS WILL SPREAD/THICKEN CLOUD COVER BACK
INTO THE REGION...WHILE INCREASING 850-500MB FRONTOGENESIS AND
ISENTROPIC LIFT AHEAD OF THE LOW EXPECTED TO PRODUCE SATURATION
THROUGH THE COLUMN FOR SNOWFALL STARTING AFTER 09Z. THIS IS EXPECTED
MAINLY SOUTHWEST OF THE I-94 CORRIDOR. TEMPERATURES SHOULD DIVE
FAIRLY QUICK THIS EVENING INTO THE SINGLE DIGITS ABOVE AND BELOW
ZERO THROUGH ABOUT MIDNIGHT...THEN SLOWLY RISE THROUGH THE EARLY
MORNING HOURS. MODEL CONSENSUS/DPROG-DT SHOW THE TRACK OF THE LOW
SHIFTING A BIT FARTHER WEST ACROSS SOUTHEAST MN/EASTERN IA IN THE
LAST FEW RUNS. THIS WOULD PUT AREAS ALONG AND WEST OF THE MISSISSIPPI
IN THE HEAVIEST SNOW AXIS. THINKING RIGHT NOW SNOWFALL OF 3-4 INCHES
LOOKS LIKELY...WITH THE BULK OF THE SNOW FALLING FROM 12Z SAT TO
AROUND 18-21Z TIME FRAME. IN ADDITION...WILL LIKELY SEE SOME BLOWING
SNOW AGAIN ACROSS PORTIONS OF NORTHEAST IA/SOUTHEAST MN LATE
SATURDAY MORNING THROUGH THE AFTERNOON HOURS. WITH ALL THIS IN
MIND...HAVE HOISTED A WINTER WEATHER ADVISORY FOR A PORTION OF
SOUTHWEST WI AND ALL OF SOUTHEAST MN/NORTHEAST IA FROM 09Z OR 3 AM
SATURDAY THROUGH 00Z SUN OR SATURDAY 6 PM.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 340 AM CST FRI JAN 17 2014
MODERATING TEMPERATURES SUNDAY THEN COLDER NORTHWEST FLOW THROUGH
THE REST OF THE WEEK WILL BE THE MAIN FORECAST CHALLENGE IN THE
LONG TERM PERIOD.
AFTER THE SNOW-PRODUCING WAVE PASSES SOUTHEAST OF THE AREA SATURDAY
NIGHT...MID-LEVEL RIDGING TAKES PLACE ACROSS THE NORTHERN PLAINS
INTO THE UPPER MISSISSIPPI RIVER VALLEY REGION. THE BUILDING RIDGE
AND INCREASING WARM AIR ADVECTION IN ADVANCE OF A COLD FRONT
DROOPING SOUTH ACROSS ONTARIO EXPECTED TO PRODUCE HIGHS ON SUNDAY IN
THE MID 20S ACROSS NORTH CENTRAL WI...TO THE LOWER AND MIDDLE 30S
ELSEWHERE.
17.00Z GFS AND ECMWF SHOWING THE COLD FRONT OVER SOUTHERN
ONTARIO...DROPPING SOUTH ACROSS THE AREA ON SUNDAY...MARKING THE END
TO THE MILDER WEATHER AND BACK TO COLDER NORTHWEST FLOW THROUGH THE
REST OF THE PERIOD. A MID-LEVEL TROUGH IN THE NORTHWEST FLOW DROPS
ACROSS THE AREA ON MONDAY FOR A CHANCE OF SOME VERY LIGHT SNOWFALL.
WILL HAVE TO KEEP A LEARY EYE ON MODEL RUNS FROM DAY TO DAY DUE TO
UNTRUSTWORTHY NORTHWEST FLOW AND HARD TO TIME EMBEDDED SHORTWAVE
TROUGHS FOR SNOW CHANCES.
OTHERWISE...TEMPERATURES WILL DROP BACK TO BELOW NORMAL LEVELS FROM
MONDAY THROUGH THURSDAY WITH HIGHS GENERALLY IN THE SINGLE DIGITS
AND TEENS ABOVE ZERO AND LOWS IN THE SINGLE DIGITS TO LOWER TEENS
BELOW ZERO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1106 PM CST THU JAN 16 2014
THE 17.00Z NAM AND 17.01Z HRRR CONTINUE TO SUGGEST THE
POSSIBILITY OF ANOTHER SNOW BAND MOVING ACROSS THE AREA
OVERNIGHT. THIS WOULD BE IN RESPONSE TO THE SHORT WAVE TROUGH OVER
NORTHWEST WISCONSIN AS IT MOVES SOUTHEAST AND PRODUCES SOME WEAK
QG CONVERGENCE OVER THE AREA. REGIONAL RADARS AND SURFACE
OBSERVATIONS DO SHOW SOME SNOW WITH THE WAVE SO HAVE CONTINUED THE
TREND OF BRINGING THIS INTO KLSE OVERNIGHT WITH MVFR CONDITIONS.
THE MODELS HAVE CUT BACK ON THE WESTERN EXTENT OF THE SNOW WHICH
SEEMS TO FIT THE CURRENT ACTIVITY AND HAVE BACKED OFF TO JUST
FLURRIES FOR KRST WITH A LOWERING OF THE CEILING. EXPECT THE SNOW
TO QUICKLY MOVE OUT FRIDAY MORNING WITH A RETURN TO VFR CONDITIONS
AND THEN THE CLOUDS SHOULD SCATTER OUT DURING THE LATE MORNING OR
EARLY AFTERNOON AS A HIGH PRESSURE RIDGE BUILDS IN. THIS RIDGE
WILL GET PUSHED SOUTH OF THE AREA FRIDAY EVENING AS THE NEXT
SYSTEM RAPIDLY ADVANCES TOWARD THE REGION. WILL SEE HIGH CLOUDS
SPILL IN DURING THE EVENING BUT REMAINING VFR.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM CST SATURDAY FOR
WIZ032-033-041-053>055-061.
MN...WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM CST SATURDAY FOR
MNZ079-086>088-094>096.
WIND CHILL ADVISORY UNTIL 11 AM CST THIS MORNING FOR MNZ086-087-
094-095.
IA...WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM CST SATURDAY FOR
IAZ008>011-018-019-029-030.
WIND CHILL ADVISORY UNTIL 11 AM CST THIS MORNING FOR IAZ008>010-
018-019-029.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1106 PM CST THU JAN 16 2014
.UPDATE...
ISSUED AT 834 PM CST THU JAN 16 2014
LATEST OBSERVATIONS NO LONGER SHOW ANY BLOWING SNOW OCCURRING
ACROSS THE AREA AND A CHECK WITH LAW ENFORCEMENT INDICATES THE
COUNTIES ARE NO LONGER HAVING ANY PROBLEMS. ANOTHER QUICK MOVING
BAND OF SNOW IS EXPECTED TO MOVE ACROSS THE WESTERN SECTIONS OF
THE FORECAST AREA LATE THIS EVENING. THIS WILL BRIEFLY DROP THE
VISIBILITY BUT ACCUMULATIONS WILL BE VERY MINOR...MAYBE A HALF
INCH AT MOST. OVERALL...NOT EXPECTING THIS NEXT ROUND OF SNOW TO
HAVE MUCH IMPACT AND IN COORDINATION WITH SURROUNDING OFFICES HAVE
DROPPED THE WINTER WEATHER ADVISORY. NO CHANGES TO THE WIND CHILL
ADVISORY WITH SOME PARTS OF THE AREA EXPECTED TO FALL BELOW 20
BELOW LATE TONIGHT INTO FRIDAY MORNING.
&&
.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 315 PM CST THU JAN 16 2014
MAIN FORECAST CONCERNS THIS PACKAGE...WINDS/BLOWING SNOW THIS
EVENING...WIND CHILLS LATER TONIGHT/FRI MORNING...NEXT SYSTEM
DROPPING INTO THE REGION FRI NIGHT...
18Z DATA ANALYSIS HAD A 995MB LOW CENTERED OVER THE U.P. OF MI WITH
ITS BROAD CIRCULATION COVERING MUCH OF THE NORTH-CENTRAL CONUS.
TIGHTER GRADIENT AND SUBSIDENCE BEHIND A COLD FRONT MOVING ACROSS
WI/EASTERN IA WAS PRODUCING STRONG/GUSTY NORTHWEST WINDS ACROSS MUCH
OF MN/IA/WESTERN WI. SNOW ACROSS THE AREA HAS GENERALLY BEEN
SHOWERY/SPOTTY WITH MINIMAL ACCUMULATIONS...WITH ONLY A 2 TO 3 HR
PERIOD OF VSBYS BELOW A COUPLE MILES IN SNOW/BLOWING SNOW WITH THE
STRONGEST WINDS RIGHT BEHIND THE FRONT. MORE SEVERE BLOWING
SNOW/POOR VSBYS WERE OVER WESTERN MN/FAR EASTERN ND WHERE SNOW
DEPTHS WERE GREATER AND WINDS WERE STILL GUSTING 30-40 MPH.
16.12Z MODELS INITIALIZED WELL AND OFFER VERY SIMILAR SOLUTIONS FOR
TONIGHT THRU FRI NIGHT. MODEL CONSENSUS CONTINUES TO FAVOR STRONGER
OF EARLIER MODEL RUNS WITH WITH THE SHORTWAVE TROUGH TO PASS TONIGHT
AND THE NEXT ONE DROPPING TOWARD THE AREA FRI NIGHT. WITH THE
STRONGER TREND IS A SLOWING TREND WITH THE FEATURES...ESPECIALLY THE
SHORTWAVE APPROACHING FRI NIGHT. CHECK AT 18Z SHOWED MOST MODELS TO
BE A BIT FAST WITH THE COLD FRONT MOVING ACROSS WI/EASTERN IA. ALL
TO HAVE A GOOD HANDLE ON THE SFC LOW AND WINDS ACROSS REGION...AND
WERE QUITE GOOD WITH ANY SNOW ACROSS MUCH OF MN/IA/WI THIS MORNING
REMAINING ON THE LIGHT SIDE. PER WV IMAGERY MODELS LOOK GOOD WITH
THE SHORTWAVE MOVING ONSHORE IN SOUTHERN AK...WHICH DROPS INTO THE
REGION FRI NIGHT. GIVEN THE TIGHT MODEL CONSENSUS...EVEN WITH THE
STRONGER TREND...FCST CONFIDENCE IS GOOD TONIGHT THRU FRI NIGHT.
IN THE SHORT TERM...ONE MORE STRONGER LOBE/SPOKE OF VORTICITY TO
DROP ACROSS THE AREA TONIGHT. AFTER A DECREASE OF CLOUDS AND SOME
SUNSHINE FOR PARTS OF THE FCST AREA TODAY...ANOTHER DEEPER BAND OF
925-700MB MOISTURE TO ROTATE SOUTH ACROSS THE FCST AREA TONIGHT
WITH/BEHIND THE SFC-700MB TROUGH. THIS WITH SOME WEAK CONVERGENCE/
LIFT LOOKS TO PRODUCE A WEAK DEFORMATION BAND OF -SN/-SHSN AS IT
PASSES TONIGHT. CONTINUED THE 40-60 PERCENT PRECIP CHANCES WITH
SCT/ OCCASIONAL -SHSN TONIGHT. NORTHWEST WINDS REMAIN BRISK
TONIGHT BUT DO GRADUALLY DIMINISH. BLOWING/DRIFTING SNOW TO
DIMINISH/END AS WELL AS WINDS DROP 5 TO 10 KTS FROM THEIR PEAK
VALUES AND GUSTINESS WANES. WILL END THE WINTER WEATHER ADVISORY
AT MIDNIGHT AND CONVERT THE 06Z-18Z PORTION TO A WIND CHILL
ADVISORY FOR 06Z-17Z. TEMPS FALLING TO AROUND ZERO LATER TONIGHT
COUPLED WITH THE 10-20 MPH WINDS STILL LOOK TO SEND WIND CHILLS
ACROSS THE WEST THIRD OF THE FCST AREA INTO THE -20 TO -30 RANGE
LATE TONIGHT/FRI MORNING.
FRI/FRI EVENING CONTINUE TO LOOK QUIET/COLD AS SFC-700MB RIDGING
BUILDS INTO/ACROSS THE AREA. 925MB TEMPS IN THE -12C TO -16C RANGE
THRU FRI FOR HIGHS SOME 15-20F COLDER THAN THOSE OF TODAY.
SLOWER MODEL SOLUTIONS DELAY THE ARRIVAL OF THE DEEPER MOISTURE/LIFT
WITH THE NEXT STRONG SHORTWAVE TO DIVE SOUTHEAST INTO THE REGION.
RATHER IMPRESSIVE 500-300MB PV ADVECTION/LIFT/DIVERGENCE ALOFT TO
SPREAD INTO THE AREA LATER FRI NIGHT. ANOTHER ROUND OF MDT TO STRONG
925-700MB WARM ADVECTION/ISENTROPIC LIFT SPREADS ACROSS THE AREA
AHEAD OF A RATHER VIGOROUS SFC-700MB LOW DROPPING TOWARD THE AREA.
DELAYED THE ARRIVAL OF THE SNOW A BIT FRI NIGHT...LEFT FRI EVENING
DRY...THEN TRENDED SNOW CHANCES UPWARD IN THE 09-12Z SAT PERIOD.
USED A BLEND OF THE GUIDANCE LOWS/HIGHS FOR TONIGHT THRU FRI NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 315 PM CST THU JAN 16 2014
FORECAST CONCERNS FOR SATURDAY THROUGH SUNDAY NIGHT...SNOW ON
SATURDAY...TEMPERATURES SATURDAY THRU SUN NIGHT.
16.12Z MODELS IN GOOD AGREEMENT WITH STRONGER TRENDING SHORTWAVE TO
DROP ACROSS THE UPPER MIDWEST SAT...HGTS TO SLOWLY RISE SAT NIGHT/
SUN THEN FALL AGAIN SUN NIGHT AS THE NEXT BROADER TROUGHING/ENERGY
DROP INTO THE UPPER MIDWEST. TREND IS TOWARD A TIGHTER COMPROMISE
CONSENSUS OF THE EARLIER RUNS THRU THE PERIOD...BUT THE STRONGER/
SLOWER TREND FROM FRI NIGHT CONTINUES SAT...AND TREND IS A BIT
STRONGER WITH THE TROUGHING MOVING IN SUN NIGHT. FCST CONFIDENCE IN
THE SAT THRU SUN NIGHT PERIOD IS GOOD.
COMING OUT OF FRI NIGHT WITH THE SLIGHT SLOWING...THE STRONGEST/
DEEPEST LIFT WITH THE SHORTWAVE AND LOWER LEVEL THERMO-DYNAMIC
FORCING NOW PROGGED TO MOVE ACROSS THE FCST SAT MORNING. MODEL
CONSENSUS OF THE SWATH OF SNOW HAS TIGHTENED...BUT CAN-GEM REMAINS A
BIT WEST OF THE MEAN AND NAM A BIT EAST OF THE MEAN. EITHER
WAY...MODEL CONSENSUS PRODUCES A BAND OF 0.1 TO AS MUCH AS 0.25
INCH OF QPF ACROSS THE AREA...MAINLY ALONG/EAST OF THE MS RIVER.
SNOW-WATER RATIOS A BIT TRICKY. DENDRITIC GROWTH ZONE NOT
EXCEPTIONALLY DEEP WITH THIS SYSTEM...BUT THE LIFT IS PROGGED TO
BE STRONG AND DEEP. USING A 15 TO 17 TO 1 SNOW-WATER RATIO STILL
PRODUCES AS MUCH AS 3 TO 4 INCHES OF SNOW ALONG/NORTHEAST OF I-94
FROM LATE FRI NIGHT INTO SAT AFTERNOON. WILL HOLD OF ON ANY
HEADLINES FOR THIS EXPECTED SNOW FALL AND GIVE MID CREW ONE MORE
SET OF MODEL RUNS TO TIGHTEN THE CONSENSUS EVEN FURTHER...PLUS THE
SHORTWAVE OF CONCERN WILL BE OVER AK/NORTHWEST CAN.
BEYOND SAT...WEATHER GENERALLY QUIET FOR SAT NIGHT THRU SUN NIGHT AS
THE SAT TROUGH ROTATES QUICKLY EAST AND THE FLOW ALOFT GRADUALLY
TURNS FROM NORTH TO WEST OVER THE AREA. COLD ADVECTION BEHIND THE
SAT SHORTWAVE IS SHORT-LIVED WITH MDT/STRONG 925-700MB WARM
ADVECTION SPREADING ACROSS THE AREA SAT NIGHT/EARLY SUNDAY. SOME
DIFFERENCE OF OPINION AMONG THE MODELS HOW MUCH LOWER LEVEL WARMING
OCCURS BY SUN AFTERNOON...925MB TEMPS PER THE ECMWF/NAM IN THE -3C
TO +3C RANGE WHILE GFS IN THE -5C TO -10C RANGE. WITH MORE WESTERLY
MID LEVEL FLOW AHEAD OF SHORTWAVE ENERGY DROPPING INTO ND/NORTHERN MN
SUN AFTERNOON...WARMER NAM/ECMWF SOLUTIONS LOOK BETTER FOR SUN AND
LEFT SUNDAY HIGHS IN THE 30S. IF WARMER ECMWF IS MORE CORRECT...
COULD EVEN BE A FEW LOW 40S ON SUN...MUCH LIKE SUNDAY JAN 12. MORE
CONSISTENT SIGNAL FOR LOW LEVEL COLD ADVECTION TO RETURN SUN NIGHT
AS LOW PRESSURE TRACKING ACROSS SOUTHERN CAN PUSHES ANOTHER COLD
FRONT SOUTH ACROSS THE UPPER MIDWEST. FAVORED WARMER OF NUMERICAL
GUIDANCE FOR SUN HIGHS...OTHERWISE STAYED WITH A MODEL/ENSEMBLE
CONSENSUS FOR HIGHS/LOWS IN THE SAT-SUN NIGHT PERIOD.
FOR MONDAY THROUGH THURSDAY.../DAYS 4 TO 7/...
16.00Z AND 16.12Z MEDIUM RANGE MODELS OFFER IMPROVING AGREEMENT IN
THE MONDAY TIME-FRAME AS HGTS FALL ACROSS THE REGION...THEN REMAIN
IN GOOD/IMPROVING AGREEMENT TUE/WED AS LONGWAVE TROUGHING DEEPENS
OVER EASTERN NOAM. DETAIL DIFFERENCES ON SHORTWAVES THRU THE NORTH-
WEST TO NORTH FLOW OVER THE REGION BECOME MORE APPARENT BY THU BUT
THIS MORE OR LESS EXPECTED IN NORTHWEST FLOW BY DAY 7. WITH THE
IMPROVING CONSISTENCY...FCST CONFIDENCE FOR TEMPS HEADING BACK BELOW
NORMAL IN THE DAY 4-7 PERIOD IS GOOD. LESSER CONFIDENCE ON ANY -SN
CHANCES MON-THU WITH PLENTY OF SMALLER SCALE SHORTWAVE STRENGTH/
TIMING DETAIL DIFFERENCES AMONG THE MODELS.
TRAIN OF SHORTWAVE ENERGY DROPS ACROSS THE REGION MON...LOWERING
HGTS AND EVENTUALLY CARVING OUT THE EASTERN NOAM TROUGH FOR MUCH
OF NEXT WEEK. REGION ENDS UP UNDER NORTHWEST TO NORTH FLOW ALOFT
MUCH OF NEXT WEEK. LEAD ENERGY MON BRINGS WITH IT A -SN CHANCE FOR
MUCH OF THE FCST AREA...BUT MORE OF AN IMPACT LOOKS TO BE THE
STRONG LOW LEVEL COLD ADVECTION MON/MON NIGHT WITH 925MB TEMPS IN
THE -18C TO -22C RANGE BY 12Z TUE. AFTER A WARMER DAY SUN...TEMPS
TO SHARPLY FALL MON/MON NIGHT...ENDING UP BELOW ZERO BY TUE
MORNING WITH POTENTIAL NEED FOR WIND CHILL HEADLINES ACROSS MOST
OR ALL OF THE AREA LATE MON NIGHT/TUE MORNING. 925MB TEMPS LOOK TO
STAY IN THE - 18C TO -22C RANGE THRU WED...WITH SOME MODEL SIGNAL
FOR A STRONGER ROUND OF LOWER LEVEL WARM ADVECTION TO SPREAD
ACROSS THE AREA THU. GIVEN THE STRENGTH/DEPTH OF THE MOISTURE/LIFT
SIGNAL...SOME MODERATE OF TEMPS AND AT LEAST A SMALL -SN CHANCE
ARE REASONABLE FOR THU. TRENDED TOWARD FALLING TEMPS
MONDAY...COLDER OF LOWS/HIGHS MON NIGHT THRU WED...WITH THE
MODEL/ENSEMBLE CONSENSUS TEMPS LOOKING GOOD FOR WED NIGHT/THU.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1106 PM CST THU JAN 16 2014
THE 17.00Z NAM AND 17.01Z HRRR CONTINUE TO SUGGEST THE
POSSIBILITY OF ANOTHER SNOW BAND MOVING ACROSS THE AREA
OVERNIGHT. THIS WOULD BE IN RESPONSE TO THE SHORT WAVE TROUGH OVER
NORTHWEST WISCONSIN AS IT MOVES SOUTHEAST AND PRODUCES SOME WEAK
QG CONVERGENCE OVER THE AREA. REGIONAL RADARS AND SURFACE
OBSERVATIONS DO SHOW SOME SNOW WITH THE WAVE SO HAVE CONTINUED THE
TREND OF BRINGING THIS INTO KLSE OVERNIGHT WITH MVFR CONDITIONS.
THE MODELS HAVE CUT BACK ON THE WESTERN EXTENT OF THE SNOW WHICH
SEEMS TO FIT THE CURRENT ACTIVITY AND HAVE BACKED OFF TO JUST
FLURRIES FOR KRST WITH A LOWERING OF THE CEILING. EXPECT THE SNOW
TO QUICKLY MOVE OUT FRIDAY MORNING WITH A RETURN TO VFR CONDITIONS
AND THEN THE CLOUDS SHOULD SCATTER OUT DURING THE LATE MORNING OR
EARLY AFTERNOON AS A HIGH PRESSURE RIDGE BUILDS IN. THIS RIDGE
WILL GET PUSHED SOUTH OF THE AREA FRIDAY EVENING AS THE NEXT
SYSTEM RAPIDLY ADVANCES TOWARD THE REGION. WILL SEE HIGH CLOUDS
SPILL IN DURING THE EVENING BUT REMAINING VFR.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WIND CHILL ADVISORY UNTIL 11 AM CST FRIDAY FOR MNZ086-087-094-
095.
IA...WIND CHILL ADVISORY UNTIL 11 AM CST FRIDAY FOR IAZ008>010-018-
019-029.
&&
$$
UPDATE...04
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...04
AREA FORECAST DISCUSSION
NWS ALBANY NY
111 AM EST SUN JAN 19 2014
.SYNOPSIS...
ISOLATED SNOW SHOWERS AND FLURRIES WILL GRADUALLY
DIMINISH EARLY THIS MORNING...AS A WEAK STORM SYSTEM TRACKS FURTHER
AWAY FROM THE REGION. ANOTHER SYSTEM FROM THE MIDWEST APPROACHES AND
BRINGS ANOTHER CHANCE FOR A LITTLE MORE SNOW TO THE REGION DURING
THE LATE MORNING AND AFTERNOON. AN ARCTIC FRONT WILL SLIDE THROUGH
THE REGION ON MONDAY WITH BITTERLY COLD TEMPERATURES FOR THE
UPCOMING WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1232 AM EST...LOW PRESSURE CONTINUES TO MOVE EAST OF THE
GULF OF MAINE EARLY THIS MORNING. SCT SNOW SHOWERS AND FLURRIES
CONTINUE TO DISSIPATE FROM THE CAPITAL DISTRICT NORTH IN THE UPPER
HUDSON RIVER VALLEY. SOME LAKE ENHANCED SNOW SHOWERS MAY INCREASE
BASED ON THE LATEST HRRR BTWN 09Z-12Z OVER THE WRN DACKS...AS A
SFC TROUGH AND ITS ASSOCIATED MID LEVEL SHORT-WAVE APPROACH FROM
W-CNTRL PA AND THE ERN GREAT LAKES. SOME WEAK LOW AND MID LEVEL
RIDGING HAS ALLOWED THE SKIES TO GO PARTLY CLOUDY IN THE MID
HUDSON VALLEY AND NW CT. TEMPS WERE LOWERED A FEW DEGREES THERE.
EXPECT LOWS TO STILL BE IN THE TEENS TO L20S. THE WINDS WILL
CONTINUE TO DIMINISH TO LESS THAN 10 MPH AND BACK TO THE SOUTH TO
SOUTHWEST EARLY THIS MORNING WITH THE WEAK RIDGING AHEAD OF THE
NEXT DISTURBANCE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
SUNDAY...
THE AFOREMENTIONED SHORT WAVE OVER THE OHIO VALLEY WILL WEAKEN A
BIT AS IT BECOMES EMBEDDED WITHIN THE CONFLUENCE ACROSS THE MID
ATLANTIC AND NORTHEAST CORRIDOR. NEVERTHELESS...THE SEEDER-FEEDER
SCENARIO REMAINS IN THE EARLY MORNING...THEN AS THE COLUMN
MOISTENS SO DOES THE INCREASE CHANCES FOR SNOW SHOWERS ACROSS THE
ENTIRE REGION. AS THIS UPPER WAVE PASSES QUICKLY TO THE
EAST...BUFR PROFILES CONTINUE TO SUGGEST LOW LEVEL LAPSE RATE ON
THE INCREASE. CYCLONIC FLOW ALOFT...GRADUAL COLD AIR ADVECTION AND
SMALL IMPULSES WITHIN THE CYCLONIC FLOW STILL POINT TOWARD THE
POTENTIAL FOR A FEW SNOW SQUALLS ACROSS THE REGION WITH THE BEST
POTENTIAL ACROSS THE TERRAIN. THIS TOO IS SEEN IN THE
EXPERIENTIAL 4KM WRF REFLECTIVITY FORECASTS WHERE WE WILL PLACE
THE HIGHER POPS DOWNWIND OF LAKE ONTARIO AND INTO THE TERRAIN.
HIGH TEMPERATURES ON SUNDAY WILL BE RATHER SIMILAR TO THOSE FROM
TODAY DUE TO THE INCREASING MIXING POTENTIAL.
SUNDAY NIGHT...
THE ARCTIC BOUNDARY WILL BE APPROACHING DURING THIS TIME
FRAME...WITH STILL SOME TIMING DIFFERENCES FROM THE LATEST
NUMERICAL GUIDANCE. TRENDS WILL FAVOR AN INCREASE IN LOW LEVEL
CONVERGENCE WHICH WILL FAVORABLY INTERACT WITH LAKE ONTARIO FOR
SNOW SHOWERS/SQUALLS INTO PORTIONS OF THE DACKS...MOHAWK
VALLEY...CATSKILLS. LAKE BANDS ARE STILL DIFFICULT TO ASCERTAIN
DUE TO INCREASE SHEAR PROFILES AND INLAND PENETRATION. WE WILL
CONTINUE TO MONITOR. SURFACE GRADIENT INCREASES AS WELL FOR A
BRISK NIGHT EXPECTED WITH WIND CHILLS DIPPING INTO THE TEENS FOR
VALLEY LOCATIONS AND AT OR BELOW ZERO FOR THE TERRAIN.
MONDAY...
ARCTIC BOUNDARY FROPA WILL OCCUR AT THE LATEST MONDAY MORNING.
WINDS WILL SHIFT TOWARD THE WEST-NORTHWEST AS H850 TEMPS BEGIN
THEIR FALL INTO THE NEGATIVE TEENS BY DAYS END. AS MENTIONED IN
PREVIOUS DISCUSSIONS...THERE IS STILL A POTENTIAL FOR A WAVE TO
DEVELOP ALONG THE ARCTIC FRONT AND BRING SOME SNOW MAINLY ALONG
AND SOUTH OF I90. THE GLOBAL MODELS REMAIN WITH THIS POSSIBILITY
WITH SHORT TERM GUIDANCE LEANING AGAINST THIS IDEA. GIVEN THE
STRENGTH OF THE UPPER TROUGH AND A COUPLE PV ANOMALIES PER THE
1.5PVU...WE WILL HOLD ONTO THE SLIGHT CHANCE TO CHANCE POPS.
OTHERWISE...THE MAIN ISSUE WILL BE FALLING TEMPERATURES DURING THE
AFTERNOON WITH BRISK CONDITIONS REMAINING.
MONDAY NIGHT...
ARCTIC AIR CONTINUES TO FILTER SOUTHWARD AS H850 TEMPS ARE
EXPECTED TO DROP BELOW -20C. FAIRLY SHALLOW INVERSION...LESS THAN
FAVORABLE WIND TRAJECTORY AND DRY AIR ADVECTING IN AT LOWER LEVELS
SHOULD MINIMIZE LAKE EFFECT POTENTIAL /JUST FLURRIES ACROSS THE
HIGHER TERRAIN/. THE HAZARDOUS WEATHER IMPACT APPEARS TO BE FROM WIND
CHILLS APPROACHING ADVISORY ACROSS THE ADIRONDACKS.
OTHERWISE...SURFACE TEMPERATURES ARE EXPECTED TO DROP WELL BELOW
ZERO ACROSS THE DACKS WITH 0-10 DEGREES ELSEWHERE.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE EXTENDED PERIOD LOOKS DRY AND MIGHTY COLD.
A LARGE RIDGE OVER THE WESTERN CONUS AND A BROAD TROUGH OVER THE
EAST WILL PRODUCE AN INCESSANT NORTHWESTERLY FLOW. THIS FLOW AND A
COUPLE OF CLIPPERS WILL DRIVE -20C TO -25C H850 TEMPERATURES ACROSS
THE REGION DURING MUCH OF THE PERIOD.
ONE CLIPPER LOOKS TO DIVE SOUTH OF OUR REGION TUESDAY...BRINGING A
REINFORCING SHOT OF ARCTIC AIR OUR WAY. ENERGY FROM THIS CLIPPER
WILL TRANSFER TO A PRODUCE A MUCH LARGER OCEAN STORM THAT THE
GFS/ECMWF AND CANADIAN MODELS TAKE WELL OUT TO SEA. THE FLOW LOOKS
TO BE MORE NORTHERLY (AS OPPOSED TO WESTERLY) WHICH COULD PREVENT
ANY LAKE EFFECT SNOW FROM HAPPENING IN OUR REGION. HAVE KEPT THE
TUESDAY THROUGH WEDNESDAY NIGHT PERIOD DRY. THERE SHOULD BE AT LEAST
SOME SUNSHINE.
THURSDAY...ANOTHER CLIPPER LOOKS TO APPROACH THE REGION...NOT AS FAR
SOUTH AS THE PREVIOUS ONE. THIS ONE COULD BRING A LITTLE LIGHT SNOW
OR SNOW SHOWERS ALTHOUGH IT WILL HAVE VERY MOISTURE TO WORK WITH
(PWATS OFF THE GFS WERE AROUND 0.1 INCHES). FOR NOW...JUST PLACED
SLIGHT CHANCES FOR SNOW SHOWERS IN FOR THURSDAY.
AFTER THAT CLIPPER RACES OFFSHORE...ANOTHER SHOT OF ARCTIC AIR LOOKS
TO ARRIVE FOR FRIDAY. AS STRONGER CLIPPER APPROACHES...TEMPERATURES
WILL MODERATE NEXT SATURDAY...BUT A SOUTHERLY WIND WILL PICK UP
NEGATING ANY BENEFIT OF SLIGHTLY LESS COLD TEMPERATURES. THERE IS A
CHANCE OF ADDITIONAL SNOW SHOWERS AS WELL.
THEREFORE...FOR MOST OF THE EXTENDED PERIOD...WE WILL BE DEALING
WITH RATHER HARSH CONDITIONS...EXACERBATED BY A NORTH TO NORTHWEST
WIND THAT COULD DRIVE WIND CHILLS TO NEAR DANGEROUS LEVELS AT TIMES.
HOW COLD WILL IT BE?
LOOK FOR DAYTIME HIGHS TUESDAY THROUGH FRIDAY TO AVERAGE IN THE
TEENS TO AROUND 20 FROM ALBANY SOUTH...ONLY SINGLE DIGITS WELL NORTH
OF ALBANY. OVERNIGHT LOWS WILL RANGE FROM AROUND ZERO TO ABUT +10
ALBANY SOUTHWARD...5 TO 15 BELOW ZERO NORTH OF THE CAPITAL REGION
AND ACROSS THE ELEVATED AREAS AS WELL.
BY SATURDAY...HIGHS LOOK TO REACH BACK INTO THE 20S ACROSS MOST OF
THE REGION.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THE WEATHER PATTERN WILL REMAIN RATHER ACTIVITY IN THE NEAR TERM.
ANOTHER LOW PRESSURE SYSTEM WILL IMPACT THE REGION TODAY AND
TONIGHT. AT THIS TIME...HAVE SOME WEAK RIDGING NOSING INTO REGION
WHICH HAS CAUSED A DECREASE IN THE CLOUD COVER IN THE MID HUDSON
VALLEY. HOWEVER THIS WILL BE SHORT LIVED AS THE RIDGE FLATTENS AND
HIGHER CLOUDS STREAM IN. LOW PRESSURE WILL PASS WELL TO OUR NORTH
TODAY AND TONIGHT MOVING EASTWARD ACROSS EASTERN CANADA DRAGGING ITS
ASSOCIATED COLD FRONT ACROSS THE REGION TONIGHT INTO MONDAY MORNING.
THIS IS THE BOUNDARY THAT WILL OPEN THE DOOR TO THE ARCTIC AIR.
AN AREA OF WEAK RETURNS HAVE DEVELOP WITH LIGHT SNOW AND FLURRIES
FROM THE CAPITAL DISTRICT NORTH IN THE UPPER HUDSON RIVER VALLEY.
MVFR CONDITIONS ARE ASSOCIATED WITH THIS ACTIVITY. IT IS EXPECTED TO
DISSIPATE OVER THE NEXT COUPLE HOURS. WILL HAVE CHANCE FOR SHOWERS
TODAY ESPECIALLY ACROSS THE HIGHER TERRAIN BUT ITS DIFFICULT TO TIME
SO HAVE RUN WITH A VICINITY SHOWER IN TAFS TO ADDRESS THREAT.
CLOUDS ARE EXPECTED TO DOMINATE WITH MAINLY VFR CONDITIONS. AT KPSF
DUE TO UPSLOPE MVFR CONDITIONS SHOULD PERSIST THROUGH THE MORNING.
IF A SNOW SHOWER IMPACTS A TAF SITES MVFR CONDITIONS WOULD BE
EXPECTED WITH BRIEF IFR POSSIBLE.
MAINLY WESTERLY WINDS SHIFTING MORE TO THE SOUTHWEST DURING THE DAY.
WHILE AT KGFL A MORE SOUTHERLY FLOW IS EXPECTED SHIFTING MORE TO THE
SOUTHWEST. WINDS WILL INCREASE AND BECOME GUSTY TODAY ESPECIALLY AT
KALB AND KPSF WITH GUSTS INTO THE 20S.
OUTLOOK...
MON NIGHT-WED NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
THU: LOW OPERATIONAL IMPACT. CHANCE OF SHSN.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THE NEXT 5 DAYS.
THROUGH THE UPCOMING WEEK...ONLY LIGHT PRECIPITATION IN THE FORM
OF SNOW IS EXPECTED ACROSS OUR AREA. THE LOW PRESSURE SYSTEM
RESPONSIBLE FOR THE SNOW INTO THIS EVENING IS EXPECTED TO PRODUCE
ONLY ONE TO TWO TENTHS OF LIQUID EQUIVALENT.
REGARDLESS...THIS PRECIP WILL HAVE LITTLE EFFECT ON THE HYDRO
SERVICE AREA RIVERS AND STREAMS. AS A RESULT...STREAM FLOWS SHOULD
GRADUALLY LOWER DURING THE NEXT 5 DAYS. ALTHOUGH...THE VERY COLD
TEMPERATURES RETURNING BY MONDAY WILL ALLOW RIVER AND LAKE ICE TO
REFORM AND THICKEN ONCE AGAIN. TEMPS WELL BELOW NORMAL WILL
CONTINUE THROUGH MOST OF THE UPCOMING WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/BGM/WASULA
NEAR TERM...HWJIV/BGM
SHORT TERM...BGM
LONG TERM...HWJIV
AVIATION...IAA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1232 AM EST SUN JAN 19 2014
.SYNOPSIS...
ISOLATED SNOW SHOWERS AND FLURRIES WILL GRADUALLY
DIMINISH EARLY THIS MORNING...AS A WEAK STORM SYSTEM TRACKS FURTHER
AWAY FROM THE REGION. ANOTHER SYSTEM FROM THE MIDWEST APPROACHES AND
BRINGS ANOTHER CHANCE FOR A LITTLE MORE SNOW TO THE REGION DURING
THE LATE MORNING AND AFTERNOON. AN ARCTIC FRONT WILL SLIDE THROUGH
THE REGION ON MONDAY WITH BITTERLY COLD TEMPERATURES FOR THE
UPCOMING WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1232 AM EST...LOW PRESSURE CONTINUES TO MOVE EAST OF THE
GULF OF MAINE EARLY THIS MORNING. SCT SNOW SHOWERS AND FLURRIES
CONTINUE TO DISSIPATE FROM THE CAPITAL DISTRICT NORTH IN THE UPPER
HUDSON RIVER VALLEY. SOME LAKE ENHANCED SNOW SHOWERS MAY INCREASE
BASED ON THE LATEST HRRR BTWN 09Z-12Z OVER THE WRN DACKS...AS A
SFC TROUGH AND ITS ASSOCIATED MID LEVEL SHORT-WAVE APPROACH FROM
W-CNTRL PA AND THE ERN GREAT LAKES. SOME WEAK LOW AND MID LEVEL
RIDGING HAS ALLOWED THE SKIES TO GO PARTLY CLOUDY IN THE MID
HUDSON VALLEY AND NW CT. TEMPS WERE LOWERED A FEW DEGREES THERE.
EXPECT LOWS TO STILL BE IN THE TEENS TO L20S. THE WINDS WILL
CONTINUE TO DIMINISH TO LESS THAN 10 MPH AND BACK TO THE SOUTH TO
SOUTHWEST EARLY THIS MORNING WITH THE WEAK RIDGING AHEAD OF THE
NEXT DISTURBANCE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
SUNDAY...
THE AFOREMENTIONED SHORT WAVE OVER THE OHIO VALLEY WILL WEAKEN A
BIT AS IT BECOMES EMBEDDED WITHIN THE CONFLUENCE ACROSS THE MID
ATLANTIC AND NORTHEAST CORRIDOR. NEVERTHELESS...THE SEEDER-FEEDER
SCENARIO REMAINS IN THE EARLY MORNING...THEN AS THE COLUMN
MOISTENS SO DOES THE INCREASE CHANCES FOR SNOW SHOWERS ACROSS THE
ENTIRE REGION. AS THIS UPPER WAVE PASSES QUICKLY TO THE
EAST...BUFR PROFILES CONTINUE TO SUGGEST LOW LEVEL LAPSE RATE ON
THE INCREASE. CYCLONIC FLOW ALOFT...GRADUAL COLD AIR ADVECTION AND
SMALL IMPULSES WITHIN THE CYCLONIC FLOW STILL POINT TOWARD THE
POTENTIAL FOR A FEW SNOW SQUALLS ACROSS THE REGION WITH THE BEST
POTENTIAL ACROSS THE TERRAIN. THIS TOO IS SEEN IN THE
EXPERIENTIAL 4KM WRF REFLECTIVITY FORECASTS WHERE WE WILL PLACE
THE HIGHER POPS DOWNWIND OF LAKE ONTARIO AND INTO THE TERRAIN.
HIGH TEMPERATURES ON SUNDAY WILL BE RATHER SIMILAR TO THOSE FROM
TODAY DUE TO THE INCREASING MIXING POTENTIAL.
SUNDAY NIGHT...
THE ARCTIC BOUNDARY WILL BE APPROACHING DURING THIS TIME
FRAME...WITH STILL SOME TIMING DIFFERENCES FROM THE LATEST
NUMERICAL GUIDANCE. TRENDS WILL FAVOR AN INCREASE IN LOW LEVEL
CONVERGENCE WHICH WILL FAVORABLY INTERACT WITH LAKE ONTARIO FOR
SNOW SHOWERS/SQUALLS INTO PORTIONS OF THE DACKS...MOHAWK
VALLEY...CATSKILLS. LAKE BANDS ARE STILL DIFFICULT TO ASCERTAIN
DUE TO INCREASE SHEAR PROFILES AND INLAND PENETRATION. WE WILL
CONTINUE TO MONITOR. SURFACE GRADIENT INCREASES AS WELL FOR A
BRISK NIGHT EXPECTED WITH WIND CHILLS DIPPING INTO THE TEENS FOR
VALLEY LOCATIONS AND AT OR BELOW ZERO FOR THE TERRAIN.
MONDAY...
ARCTIC BOUNDARY FROPA WILL OCCUR AT THE LATEST MONDAY MORNING.
WINDS WILL SHIFT TOWARD THE WEST-NORTHWEST AS H850 TEMPS BEGIN
THEIR FALL INTO THE NEGATIVE TEENS BY DAYS END. AS MENTIONED IN
PREVIOUS DISCUSSIONS...THERE IS STILL A POTENTIAL FOR A WAVE TO
DEVELOP ALONG THE ARCTIC FRONT AND BRING SOME SNOW MAINLY ALONG
AND SOUTH OF I90. THE GLOBAL MODELS REMAIN WITH THIS POSSIBILITY
WITH SHORT TERM GUIDANCE LEANING AGAINST THIS IDEA. GIVEN THE
STRENGTH OF THE UPPER TROUGH AND A COUPLE PV ANOMALIES PER THE
1.5PVU...WE WILL HOLD ONTO THE SLIGHT CHANCE TO CHANCE POPS.
OTHERWISE...THE MAIN ISSUE WILL BE FALLING TEMPERATURES DURING THE
AFTERNOON WITH BRISK CONDITIONS REMAINING.
MONDAY NIGHT...
ARCTIC AIR CONTINUES TO FILTER SOUTHWARD AS H850 TEMPS ARE
EXPECTED TO DROP BELOW -20C. FAIRLY SHALLOW INVERSION...LESS THAN
FAVORABLE WIND TRAJECTORY AND DRY AIR ADVECTING IN AT LOWER LEVELS
SHOULD MINIMIZE LAKE EFFECT POTENTIAL /JUST FLURRIES ACROSS THE
HIGHER TERRAIN/. THE HAZARDOUS WEATHER IMPACT APPEARS TO BE FROM WIND
CHILLS APPROACHING ADVISORY ACROSS THE ADIRONDACKS.
OTHERWISE...SURFACE TEMPERATURES ARE EXPECTED TO DROP WELL BELOW
ZERO ACROSS THE DACKS WITH 0-10 DEGREES ELSEWHERE.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE EXTENDED PERIOD LOOKS DRY AND MIGHTY COLD.
A LARGE RIDGE OVER THE WESTERN CONUS AND A BROAD TROUGH OVER THE
EAST WILL PRODUCE AN INCESSANT NORTHWESTERLY FLOW. THIS FLOW AND A
COUPLE OF CLIPPERS WILL DRIVE -20C TO -25C H850 TEMPERATURES ACROSS
THE REGION DURING MUCH OF THE PERIOD.
ONE CLIPPER LOOKS TO DIVE SOUTH OF OUR REGION TUESDAY...BRINGING A
REINFORCING SHOT OF ARCTIC AIR OUR WAY. ENERGY FROM THIS CLIPPER
WILL TRANSFER TO A PRODUCE A MUCH LARGER OCEAN STORM THAT THE
GFS/ECMWF AND CANADIAN MODELS TAKE WELL OUT TO SEA. THE FLOW LOOKS
TO BE MORE NORTHERLY (AS OPPOSED TO WESTERLY) WHICH COULD PREVENT
ANY LAKE EFFECT SNOW FROM HAPPENING IN OUR REGION. HAVE KEPT THE
TUESDAY THROUGH WEDNESDAY NIGHT PERIOD DRY. THERE SHOULD BE AT LEAST
SOME SUNSHINE.
THURSDAY...ANOTHER CLIPPER LOOKS TO APPROACH THE REGION...NOT AS FAR
SOUTH AS THE PREVIOUS ONE. THIS ONE COULD BRING A LITTLE LIGHT SNOW
OR SNOW SHOWERS ALTHOUGH IT WILL HAVE VERY MOISTURE TO WORK WITH
(PWATS OFF THE GFS WERE AROUND 0.1 INCHES). FOR NOW...JUST PLACED
SLIGHT CHANCES FOR SNOW SHOWERS IN FOR THURSDAY.
AFTER THAT CLIPPER RACES OFFSHORE...ANOTHER SHOT OF ARCTIC AIR LOOKS
TO ARRIVE FOR FRIDAY. AS STRONGER CLIPPER APPROACHES...TEMPERATURES
WILL MODERATE NEXT SATURDAY...BUT A SOUTHERLY WIND WILL PICK UP
NEGATING ANY BENEFIT OF SLIGHTLY LESS COLD TEMPERATURES. THERE IS A
CHANCE OF ADDITIONAL SNOW SHOWERS AS WELL.
THEREFORE...FOR MOST OF THE EXTENDED PERIOD...WE WILL BE DEALING
WITH RATHER HARSH CONDITIONS...EXACERBATED BY A NORTH TO NORTHWEST
WIND THAT COULD DRIVE WIND CHILLS TO NEAR DANGEROUS LEVELS AT TIMES.
HOW COLD WILL IT BE?
LOOK FOR DAYTIME HIGHS TUESDAY THROUGH FRIDAY TO AVERAGE IN THE
TEENS TO AROUND 20 FROM ALBANY SOUTH...ONLY SINGLE DIGITS WELL NORTH
OF ALBANY. OVERNIGHT LOWS WILL RANGE FROM AROUND ZERO TO ABUT +10
ALBANY SOUTHWARD...5 TO 15 BELOW ZERO NORTH OF THE CAPITAL REGION
AND ACROSS THE ELEVATED AREAS AS WELL.
BY SATURDAY...HIGHS LOOK TO REACH BACK INTO THE 20S ACROSS MOST OF
THE REGION.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 1045 PM EST...THE SNOW HAS PRETTY MUCH ENDED OR TAPERED TO
FLURRIES AT ALL THE TAF SITES. THEY SHOULD GENERALLY BE VFR
OVERNIGHT WITH PERHAPS VFR CIGS EVEN GOING SCATTERED. HOWEVER...
THERE COULD BE BRIEFLY MVFR CIGS...ESPECIALLY AT KPSF. IF SOME
CLEARING WERE TO TAKE PLACE AT KGFL...IT IS POSSIBLE THAT IFR FOG
COULD BRIEFLY POP UP. THE RISK OF THIS LOOKED LOW ENOUGH (UNDER 50
PERCENT)...TO EMIT FROM THE TAFS...BUT DID INCLUDE MIFG FOR NOW.
OTHERWISE...ENOUGH OF A BREEZE AT THE OTHER TERMINAL SITES WILL
INSURE GOOD VISIBILITIES OVERNIGHT. THAT BREEZE WILL BE WEST TO
SOUTHWEST 5-10KTS...WITH GUSTS TO 20KTS OR A LITTLE HIGHER AT
KALB/KPSF UNTIL A LITTLE AFTER MIDNIGHT.
THE NEXT DISTURBANCE WILL KEEP CLOUDS AROUND SUNDAY BUT IT NOW LOOKS
AS THE THREAT OF SNOW IMPACTING THE TERMINALS IS LOW AS THE CENTER
OF THE NEXT DISTURBANCE LOOKS TO LIFT TO THE NORTH OF THE TERMINALS.
WE LOOK FOR MAINLY VFR CONDITIONS TO PREVAIL...WITH THE CLOUDS JUST
ABOVE THE VFR/MVFR THRESHOLD...EXCEPT AT KPSF WHERE WE HOLD THEM AT
3000 FEET AGL.
THE WIND ON SUNDAY WILL TURN SOUTH OR SOUTHWESTERLY...AVERAGING
CLOSE TO 10KTS...WITH GUST TO 20 AT KALB AND KPSF.
OUTLOOK...
SUN NIGHT THROUGH TUESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
WEDNESDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
WEDNESDAY NIGHT THROUGH THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THE NEXT 5 DAYS.
THROUGH THE UPCOMING WEEK...ONLY LIGHT PRECIPITATION IN THE FORM
OF SNOW IS EXPECTED ACROSS OUR AREA. THE LOW PRESSURE SYSTEM
RESPONSIBLE FOR THE SNOW INTO THIS EVENING IS EXPECTED TO PRODUCE
ONLY ONE TO TWO TENTHS OF LIQUID EQUIVALENT.
REGARDLESS...THIS PRECIP WILL HAVE LITTLE EFFECT ON THE HYDRO
SERVICE AREA RIVERS AND STREAMS. AS A RESULT...STREAM FLOWS SHOULD
GRADUALLY LOWER DURING THE NEXT 5 DAYS. ALTHOUGH...THE VERY COLD
TEMPERATURES RETURNING BY MONDAY WILL ALLOW RIVER AND LAKE ICE TO
REFORM AND THICKEN ONCE AGAIN. TEMPS WELL BELOW NORMAL WILL
CONTINUE THROUGH MOST OF THE UPCOMING WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/BGM/WASULA
NEAR TERM...WASULA
SHORT TERM...BGM
LONG TERM...HWJIV
AVIATION...HWJIV
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1236 AM EST SUN JAN 19 2014
.SYNOPSIS...
AN APPROACHING COLD FRONT WILL MOVE THROUGH THE FORECAST AREA EARLY
SUNDAY. A PRESSURE RIDGE WILL BE SOUTH OF THE AREA SUNDAY THROUGH
MONDAY. ANOTHER COLD FRONT WILL SWEEP THROUGH THE AREA TUESDAY.
ARCTIC HIGH PRESSURE BEHIND THIS FRONT WILL DOMINATE WEDNESDAY
THROUGH FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
THE APPROACHING COLD FRONT WILL BE NEAR THE FORECAST AREA TOWARD
SUNRISE. LATEST HRRR INDICATES SOME PRECIPITATION ASSOCIATED WITH
THE FRONT MAY MOVE INTO THE AREA JUST BEFORE SUNRISE...BUT THINK
THE AIRMASS IS TOO DRY...AND LATEST MET GUIDANCE INDICATING POPS
LESS THAN 20 PERCENT. THIS APPEARS REASONABLE BECAUSE OF THE
PRESSURE RIDGE SOUTH OF THE AREA CONTINUING TO LIMIT MOISTURE
AHEAD OF THE FRONT. MIXING AND CLOUDINESS SHOULD HELP HOLD UP
TEMPERATURES TONIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/...
FURTHER DRYING WILL OCCUR BEHIND THE COLD FRONT SUNDAY MORNING. IT
WILL BE BREEZY. THE NAM BUFKIT MOMENTUM TRANSFER TOOL SUPPORTS GUSTS
NEAR 25 KNOTS. A LAKE WIND ADVISORY MAY BE NEEDED. THE SURFACE RIDGE
SOUTH OF THE AREA WILL CONTINUE TO MAINTAIN A DRY WESTERLY FLOW WITH
LITTLE MOISTURE RECOVERY AHEAD OF THE NEXT COLD FRONT APPROACHING
MONDAY. THE TEMPERATURE GUIDANCE WAS CLOSE. WARMING AHEAD OF THE
COLD FRONT WILL SUPPORT ABOVE NORMAL HIGH TEMPERATURES MONDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
THE GFS AND ECMWF MAINTAIN UPPER-LEVEL TROUGHING OVER THE EASTERN
PART OF THE NATION DURING THE MEDIUM-RANGE PERIOD. THE MODELS
INDICATE LITTLE MOISTURE ASSOCIATED WITH REINFORCING COLD FRONTS
TUESDAY AND THURSDAY. THE GFS...ECMWF...AND EKD MOS SUPPORT NEAR
NORMAL TEMPERATURES TUESDAY DURING THE TIME OF FRONTAL PASSAGE. THE
GUIDANCE INDICATES MUCH BELOW NORMAL TEMPERATURES DURING THE REST
OF THE PERIOD.
&&
.AVIATION /06Z SUNDAY THROUGH FRIDAY/...
HIGH CONFIDENCE IN VFR CONDITIONS THROUGH THE TAF PERIOD.
WV LOOP SHOWS A DEEP TROUGH APPROACHING THE CAROLINAS TONIGHT. AT
THE SURFACE A COLD FRONT IS WILL APPROACH THE REGION OVERNIGHT AND
MOVE ACROSS THE REGION SUNDAY MORNING. SOUTHWEST WINDS TONIGHT
AROUND 5 TO 6 KTS AHEAD OF THE FRONT WILL SHIFT TO THE WEST AND
INCREASE AND BECOME GUSTY THROUGH MUCH OF THE DAY. MAINLY MID/HIGH
LEVEL CLOUDINESS ASSOCIATED WITH THE FRONT AS IT MOVES ACROSS THE
REGION. BY SUNDAY EVENING...WINDS WILL DIMINISH AND BE FROM THE WEST
AROUND 5 KTS.
EXTENDED AVIATION OUTLOOK...BREEZY CONDITIONS POSSIBLE AT TIMES
THROUGH THURSDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
320 AM CST SUN JAN 19 2014
.DISCUSSION...
923 PM CST
LATE EVENING UPDATE...
ALL WINTER HEADLINES HAVE EXPIRED OR BEEN CANCELLED THIS EVENING AS
SHORT-WAVE DISTURBANCE RESPONSIBLE FOR EARLIER SNOW MOVES OFF INTO
INDIANA AND OHIO OVERNIGHT.
SUBSIDENCE IN THE WAKE OF THIS FEATURE HAS ERODED CLOUD COVER OVER A
LARGE PORTION OF THE FORECAST AREA AS OF 9 PM CST...WHICH ALONG WITH
LIGHT WINDS ASSOCIATED WITH COL AREA NORTH OF SFC LOW HAS ALLOWED
SOME PATCHY SHALLOW FOG TO DEVELOP ACROSS PARTS OF THE CHICAGO METRO
AND NORTHWEST INDIANA. FOG SHOULD NOT LAST TOO LONG...AS WINDS BACK
TO THE WEST-NORTHWEST AND INCREASE A BIT BY MIDNIGHT OR SO WHICH
SHOULD ALLOW FOR ENOUGH MIXING TO DISSIPATE IT. THOSE SAME
CLEAR/CALM WIND CONDITIONS OVER OUR NEW SNOW COVER WERE ALSO
ALLOWING TEMPS TO DROP OFF QUICKLY ACROSS THE AREA...WITH SOME
SINGLE DIGIT READINGS ALREADY IN OUR TYPICALLY GOOD RADIATIONAL
COOLING SPOTS ACROSS NORTH CENTRAL IL AND THE FOX VALLEY AREA. HAVE
LOWERED MINS A BIT ACROSS NORTHERN IL OVERNIGHT...WITH TEMP TREND IN
HOURLY GRIDS ACTUALLY STABILIZING OR COMING BACK UP A BIT AFTER
MIDNIGHT WITH DEVELOPMENT OF AFOREMENTIONED WIND/MIXING.
OTHERWISE...NO OTHER SIGNIFICANT CHANGES TO GOING FORECAST.
RATZER
//PREV DISCUSSION...
228 PM CST
REST OF TODAY...
SURFACE LOW IS DIVING SOUTHEAST INTO WEST CENTRAL ILLINOIS THIS
AFTERNOON WITH A NARROW BAND OF MODERATE TO HEAVY SNOW STRETCHING
ACROSS NORTH CENTRAL ILLINOIS INTO NORTHWEST INDIANA. SYSTEM HAS
BEEN FAIRLY WELL BEHAVED SO FAR WITH REPORTS OF AROUND 3-4 INCHES IN
THE AREAS THAT HAVE SEEN THE MOST SNOW THUS FAR. DECENT PACKING OF
THE PRESSURE IS NOTED ON THE 280-285K THETA SURFACES...WITH THE BEST
ASCENT PROGGED TO GRADUALLY SHIFT SOUTHEAST OUT OF THE CWA BY MID
EVENING. RAP H7 F-GEN SEEMS TO INITIALIZE NICELY...LINING UP WELL
WITH RADAR AND STRETCHING FROM THE SOUTH SUBURBS INTO NORTHWEST
INDIANA...AND PIVOTING TO THE EAST OUT OF THE AREA. THE RAP DOES
PICK UP ON F-GEN RESTRENGTHENING THIS EVENING OVER A SIMILAR AREA
AND GRADUALLY SINKING SOUTH ACROSS THE REMAINDER OF THE CWA BY LATE
THIS EVENING. WITH THIS IN MIND...DID SLOW DOWN THE TIMING OF SNOW
ENDING THIS EVENING IN THE GRIDS BY A FEW HOURS.
TONIGHT THROUGH SUNDAY...
THE POTENT UPPER WAVE THAT IMPACTED THE AREA TODAY WILL DEPART
ACROSS THE OHIO VALLEY THIS EVENING AND TONIGHT WITH MID/UPPER
RIDGING BUILDING INTO THE UPPER MIDWEST AND WESTERN LAKES REGION.
STRONG SFC PRESSURE RISES WILL MOVE IN BEHIND THE QUICKLY DEPARTING
LOW AND IS EXPECTED TO LEAD TO BREEZY CONDITIONS THIS
EVENING...MAINLY SOUTH OF I-80. FAIRLY STRONG HEIGHT RISES ALOFT
WILL ALSO OVERSPREAD THE AREA...PERSISTING THROUGH THE DAY SUNDAY
AND SHOULD PROVIDE A BRIEF RESPITE IN THE PRECIPITATION. ONCE THE
SURFACE/LOW LEVEL RIDGE AXIS PASSES OVER THE AREA LATE
TONIGHT...WINDS WILL BACK TO THE SOUTHWEST AND WARMER AIR WILL
ADVECT OVERHEAD...WITH H85 TEMPS RISING TO AROUND 2-3C BY SUNDAY
MORNING. SURFACE TEMPERATURES SHOULD REBOUND TO NEAR THE FREEZING
MARK DURING THE DAY SUNDAY...OTHERWISE SHOULD BE A QUIET WEATHER DAY
TOMORROW.
MONDAY THROUGH TUESDAY ...
MAIN CONCERN AS WE HEAD INTO NEXT WEEK WILL BE THE RETURN OF COLD
ARCTIC AIR. WEST COAST RIDGE IS PROGGED TO AMPLIFY OVER THE
WEEKEND...STRETCHING NORTH ACROSS ALASKA WHICH IN COMBINATION WITH A
DEEPENING LOW OVER ONTARIO WILL DISLODGE AIR FROM THE ARCTIC SOUTH
INTO THE NORTHERN LAKES REGION SUNDAY INTO MONDAY. THE LEADING EDGE
OF THIS COLD AIRMASS WILL SINK SOUTH BEHIND A COLD FRONT THAT WILL
PASS SOUTH OVER THE AREA EARLY MONDAY. TEMPERATURES BEHIND THE FRONT
ARE EXPECTED TO BE FALLING THROUGH THE DAY MONDAY. H85 TEMPS ARE
EXPECTED TO FALL TO AROUND -20C AND GENERALLY PERSIST THROUGH THE
END OF THE WEEK. STEEP LOW LEVEL LAPSE RATES DEVELOP BEHIND THE
FRONT AND APPEARS FAVORABLE FOR COLD AIR CU WITH SOME FLURRIES
DEVELOPING IF NOT A FEW SNOW SHOWERS. ACROSS NORTHWEST
INDIANA...WILL ALSO HAVE TO KEEP AN EYE ON THE LAKE EFFECT MACHINE
WHICH WILL BE RAMPING UP...AND APPEARS VERY FAVORABLE TO SEE SOME
SIGNIFICANT SNOW ACCUMULATIONS IN OR NEAR OUR EASTERN COUNTIES.
OVER LAND...LAPSE RATES WEAKEN MONDAY NIGHT AND APPEARS THAT WE
SHOULD BE WELL ENTRENCHED IN THE COLD/DRY AIR TUESDAY LEADING TO
MOST AREAS STAYING DRY OUTSIDE OF THE LAKE EFFECT.
WEDNESDAY THROUGH FRIDAY...
REGION REMAINS UNDER AN ACTIVE NORTHWEST FLOW PATTERN THROUGH THE
END OF NEXT WEEK RESULTING IN SEVERAL PERIODS OF SNOWFALL AS WAVES
ROTATE ACROSS THE AREA. MODELS HAVE BEEN TRENDING TOWARDS A MORE
ROBUST UPPER WAVE DROPPING ACROSS THE REGION MIDWEEK. SHOULD THIS
PAN OUT...MIGHT SEE A BRIEF/MODEST WARMUP AHEAD OF THE SYSTEM...BUT
THEN EVEN COLDER AIR SPILLING BEHIND. BOTH GEM AND ECMWF INDICATE
TEMPS FALLING TO AROUND -24C AT H85 WEDNESDAY. WHILE ITS PROBABLY A
BIT FAR OUT TO START TALKING LOW TRACK AND POTENTIAL SNOW...FOR NOW
AT LEAST MODELS INDICATE THE LOW WILL STAY NORTH OF THE CWA.
TEMPERATURES SHOULD REMAIN WELL BELOW NORMAL WEDNESDAY AND
THURSDAY...AND ARE EXPECTED TO BEGIN TO MODERATE SOME BY FRIDAY.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* SHALLOW GROUND FOG MAINLY WEST/SOUTH OF TAF SITES THRU 11Z.
* GUSTY WINDS FROM 230-250 DEG UP TO 28 KT DEVELOP ARND 14Z AND
PERSIST THRU 00Z.
* GUSTY WINDS WILL LIKELY CREATE BLOWING SNOW AND SLIGHT REDUCTION
TO VSBYS...BUT VSBYS SHUD REMAIN 6SM OR GREATER.
BEACHLER
//DISCUSSION...UPDATED 06Z...
IN THE WAKE OF THE SFC LOW/CLIPPER SYSTEM...THE WINDS HAVE BECOME
VERY LGT TO VRB AT TIMES. THE ABUNDANCE OF LINGERING NEAR SFC
MOISTURE WITH CLEARING SKIES ALOFT...AS ALLOWED PATCHY SHALLOW FOG
TO DEVELOP. THIS ONLY APPEARS TO BE TEMPORARY AS WINDS ARE
BEGINNING TO INCREASE FROM THE WEST/NORTHWEST. IR IMAGERY ALSO
INDICATES A THICK MID/UPR LVL CLOUD SHIELD ROTATING SOUTHEAST
TOWARDS NORTHERN IL/NORTHWEST IN AIRFIELDS. TIMING APPEARS TO
ARRIVE AT TAF SITES ARND 12Z AND STEADILY THICKENS. GUIDANCE HAS
BEEN CONSISTENT WITH CONSIDERABLE WIND DEVELOPING JUST AFT
DAYBREAK...WITH WINDS BECOMING WEST AND GUSTING AT TIMES TO 28KT.
IT DOES APPEARS THE GRADIENT BEGINS TO SLACKEN SOMEWHAT BY
18-20Z...THEN CLOSER TO 00Z THE FURTHER DIMINISHES WITH WINDS
BEGINNING TO TURN NORTHWESTERLY AGAIN. CLOUDS LINGER THROUGHOUT
THE AFTN/EVE TIMEFRAME...WITH SOME PATCHY MVFR CIGS DEVELOPING AFT
06Z MON.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH CONFIDENCE IN WIND DIR/SPEED/GUSTS.
* MEDIUM/HIGH CONFIDENCE IN TIMING OF GUSTS AND BLOWING SNOW
DEVELOPING.
* HIGH CONFIDENCE IN ALL OTHER ELEMENTS.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...CHANCE SNOW SHOWERS...MVFR POSSIBLE.
TUESDAY...MAINLY VFR.
WEDNESDAY THROUGH FRIDAY...PERIODIC CHANCE FOR SNOW SHOWERS AND
MVFR. OTHERWISE VFR.
MDB
&&
.MARINE...
308 AM CST
GALES BEGINNING TO DEVELOP ACROSS THE NORTHERN HALF OF THE
LAKE...AND WINDS WILL EVENTUALLY INCREASE FURTHER SOUTH WITH GALES
DEVELOPING AROUND DAYBREAK. THE STRONG LOW PRESSURE OVER EASTERN
ONTARIO EARLY THIS MORNING...HAS A TRAILING FRONTAL BOUNDARY THAT
WAS SLIDING SOUTH ACROSS THE LAKE. THE GRADIENT IS EXPECTED TO
TIGHTEN UP IN THIS FRONTAL BOUNDARY REGION. GUIDANCE HAS BEEN
CONSISTENT WITH THE GALES DEVELOPING FOR THE SOUTHERN HALF OF THE
LAKE LATER THIS MORNING...AND PERSISTING THROUGH THE AFTERNOON
HOURS. THEN THE GRADIENT WILL BEGIN TO SLACKEN OFF...AND WINDS
TURN NORTHWEST/NORTH. THIS WILL LIKELY MAINTAING HAZARDOUS WAVES
FOR THE INDIANA NEARSHORE WATERS AND POSSIBLY THE ILLINOIS
NEARSHORE FOR LATE TONIGHT INTO MONDAY.
THEN THE ACTIVE PATTERN CONTINUES FOR THE UPCOMING WEEK. A STRONG
RIDGE OF HIGH PRESSURE IS FORECAST TO DEVELOP ACROSS CENTRAL
CANADA AND SLIDE SOUTH INTO THE CENTRAL PLAINS MONDAY NIGHT INTO
TUESDAY. GUIDANCE IS FORECASTING WINDS TO INCREASE TOWARDS
30KT...POSSIBLY A FEW GALES FOR THE OPEN WATERS. THEN THIS SFC
RIDGE DRIFTS EAST TUE...UNFORTUNATELY THE GRADIENT REMAINS TIGHT
FROM THE NORTH/NORTHWEST THROUGH TUESDAY AFTN. WINDS BRIEFLY
DIMINISH WED...BEFORE YET ANOTHER CLIPPER SYSTEM SKIRTS SOUTHEAST
ACROSS THE UPPER MIDWEST/NORTHERN GREAT LAKES WED. WED NGT/THUR
THIS SYSTEM PUSHES EAST OF THE WESTERN GREAT LAKES...HOWEVER YET
ANOTHER STRONG SFC RIDGE OF HIGH PRESSURE IS EXPECTED TO PUSH INTO
THE CENTRAL PLAINS. THIS IS LIKELY GOING TO SETUP A PERIOD OF
GALES FOR THUR AFTN THROUGH FRI FOR THE OPEN WATERS.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 9 AM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745...9 AM SUNDAY TO 4 PM SUNDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868 UNTIL 3 PM SUNDAY.
GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM SUNDAY.
SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 10 PM SUNDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1202 AM CST SUN JAN 19 2014
.DISCUSSION...
923 PM CST
LATE EVENING UPDATE...
ALL WINTER HEADLINES HAVE EXPIRED OR BEEN CANCELLED THIS EVENING AS
SHORT-WAVE DISTURBANCE RESPONSIBLE FOR EARLIER SNOW MOVES OFF INTO
INDIANA AND OHIO OVERNIGHT.
SUBSIDENCE IN THE WAKE OF THIS FEATURE HAS ERODED CLOUD COVER OVER A
LARGE PORTION OF THE FORECAST AREA AS OF 9 PM CST...WHICH ALONG WITH
LIGHT WINDS ASSOCIATED WITH COL AREA NORTH OF SFC LOW HAS ALLOWED
SOME PATCHY SHALLOW FOG TO DEVELOP ACROSS PARTS OF THE CHICAGO METRO
AND NORTHWEST INDIANA. FOG SHOULD NOT LAST TOO LONG...AS WINDS BACK
TO THE WEST-NORTHWEST AND INCREASE A BIT BY MIDNIGHT OR SO WHICH
SHOULD ALLOW FOR ENOUGH MIXING TO DISSIPATE IT. THOSE SAME
CLEAR/CALM WIND CONDITIONS OVER OUR NEW SNOW COVER WERE ALSO
ALLOWING TEMPS TO DROP OFF QUICKLY ACROSS THE AREA...WITH SOME
SINGLE DIGIT READINGS ALREADY IN OUR TYPICALLY GOOD RADIATIONAL
COOLING SPOTS ACROSS NORTH CENTRAL IL AND THE FOX VALLEY AREA. HAVE
LOWERED MINS A BIT ACROSS NORTHERN IL OVERNIGHT...WITH TEMP TREND IN
HOURLY GRIDS ACTUALLY STABILIZING OR COMING BACK UP A BIT AFTER
MIDNIGHT WITH DEVELOPMENT OF AFOREMENTIONED WIND/MIXING.
OTHERWISE...NO OTHER SIGNIFICANT CHANGES TO GOING FORECAST.
RATZER
//PREV DISCUSSION...
228 PM CST
REST OF TODAY...
SURFACE LOW IS DIVING SOUTHEAST INTO WEST CENTRAL ILLINOIS THIS
AFTERNOON WITH A NARROW BAND OF MODERATE TO HEAVY SNOW STRETCHING
ACROSS NORTH CENTRAL ILLINOIS INTO NORTHWEST INDIANA. SYSTEM HAS
BEEN FAIRLY WELL BEHAVED SO FAR WITH REPORTS OF AROUND 3-4 INCHES IN
THE AREAS THAT HAVE SEEN THE MOST SNOW THUS FAR. DECENT PACKING OF
THE PRESSURE IS NOTED ON THE 280-285K THETA SURFACES...WITH THE BEST
ASCENT PROGGED TO GRADUALLY SHIFT SOUTHEAST OUT OF THE CWA BY MID
EVENING. RAP H7 F-GEN SEEMS TO INITIALIZE NICELY...LINING UP WELL
WITH RADAR AND STRETCHING FROM THE SOUTH SUBURBS INTO NORTHWEST
INDIANA...AND PIVOTING TO THE EAST OUT OF THE AREA. THE RAP DOES
PICK UP ON F-GEN RESTRENGTHENING THIS EVENING OVER A SIMILAR AREA
AND GRADUALLY SINKING SOUTH ACROSS THE REMAINDER OF THE CWA BY LATE
THIS EVENING. WITH THIS IN MIND...DID SLOW DOWN THE TIMING OF SNOW
ENDING THIS EVENING IN THE GRIDS BY A FEW HOURS.
TONIGHT THROUGH SUNDAY...
THE POTENT UPPER WAVE THAT IMPACTED THE AREA TODAY WILL DEPART
ACROSS THE OHIO VALLEY THIS EVENING AND TONIGHT WITH MID/UPPER
RIDGING BUILDING INTO THE UPPER MIDWEST AND WESTERN LAKES REGION.
STRONG SFC PRESSURE RISES WILL MOVE IN BEHIND THE QUICKLY DEPARTING
LOW AND IS EXPECTED TO LEAD TO BREEZY CONDITIONS THIS
EVENING...MAINLY SOUTH OF I-80. FAIRLY STRONG HEIGHT RISES ALOFT
WILL ALSO OVERSPREAD THE AREA...PERSISTING THROUGH THE DAY SUNDAY
AND SHOULD PROVIDE A BRIEF RESPITE IN THE PRECIPITATION. ONCE THE
SURFACE/LOW LEVEL RIDGE AXIS PASSES OVER THE AREA LATE
TONIGHT...WINDS WILL BACK TO THE SOUTHWEST AND WARMER AIR WILL
ADVECT OVERHEAD...WITH H85 TEMPS RISING TO AROUND 2-3C BY SUNDAY
MORNING. SURFACE TEMPERATURES SHOULD REBOUND TO NEAR THE FREEZING
MARK DURING THE DAY SUNDAY...OTHERWISE SHOULD BE A QUIET WEATHER DAY
TOMORROW.
MONDAY THROUGH TUESDAY ...
MAIN CONCERN AS WE HEAD INTO NEXT WEEK WILL BE THE RETURN OF COLD
ARCTIC AIR. WEST COAST RIDGE IS PROGGED TO AMPLIFY OVER THE
WEEKEND...STRETCHING NORTH ACROSS ALASKA WHICH IN COMBINATION WITH A
DEEPENING LOW OVER ONTARIO WILL DISLODGE AIR FROM THE ARCTIC SOUTH
INTO THE NORTHERN LAKES REGION SUNDAY INTO MONDAY. THE LEADING EDGE
OF THIS COLD AIRMASS WILL SINK SOUTH BEHIND A COLD FRONT THAT WILL
PASS SOUTH OVER THE AREA EARLY MONDAY. TEMPERATURES BEHIND THE FRONT
ARE EXPECTED TO BE FALLING THROUGH THE DAY MONDAY. H85 TEMPS ARE
EXPECTED TO FALL TO AROUND -20C AND GENERALLY PERSIST THROUGH THE
END OF THE WEEK. STEEP LOW LEVEL LAPSE RATES DEVELOP BEHIND THE
FRONT AND APPEARS FAVORABLE FOR COLD AIR CU WITH SOME FLURRIES
DEVELOPING IF NOT A FEW SNOW SHOWERS. ACROSS NORTHWEST
INDIANA...WILL ALSO HAVE TO KEEP AN EYE ON THE LAKE EFFECT MACHINE
WHICH WILL BE RAMPING UP...AND APPEARS VERY FAVORABLE TO SEE SOME
SIGNIFICANT SNOW ACCUMULATIONS IN OR NEAR OUR EASTERN COUNTIES.
OVER LAND...LAPSE RATES WEAKEN MONDAY NIGHT AND APPEARS THAT WE
SHOULD BE WELL ENTRENCHED IN THE COLD/DRY AIR TUESDAY LEADING TO
MOST AREAS STAYING DRY OUTSIDE OF THE LAKE EFFECT.
WEDNESDAY THROUGH FRIDAY...
REGION REMAINS UNDER AN ACTIVE NORTHWEST FLOW PATTERN THROUGH THE
END OF NEXT WEEK RESULTING IN SEVERAL PERIODS OF SNOWFALL AS WAVES
ROTATE ACROSS THE AREA. MODELS HAVE BEEN TRENDING TOWARDS A MORE
ROBUST UPPER WAVE DROPPING ACROSS THE REGION MIDWEEK. SHOULD THIS
PAN OUT...MIGHT SEE A BRIEF/MODEST WARMUP AHEAD OF THE SYSTEM...BUT
THEN EVEN COLDER AIR SPILLING BEHIND. BOTH GEM AND ECMWF INDICATE
TEMPS FALLING TO AROUND -24C AT H85 WEDNESDAY. WHILE ITS PROBABLY A
BIT FAR OUT TO START TALKING LOW TRACK AND POTENTIAL SNOW...FOR NOW
AT LEAST MODELS INDICATE THE LOW WILL STAY NORTH OF THE CWA.
TEMPERATURES SHOULD REMAIN WELL BELOW NORMAL WEDNESDAY AND
THURSDAY...AND ARE EXPECTED TO BEGIN TO MODERATE SOME BY FRIDAY.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* PATCHY MVFR CIGS SHUD QUICKLY IMPROVE TO VFR BY 630-7Z.
* SHALLOW GROUND FOG MAINLY WEST/SOUTH OF TAF SITES THRU 7Z.
* GUSTY WINDS FROM 230-250 DEG UP TO 28 KT DEVELOP ARND 14Z AND
PERSIST THRU 00Z.
* GUSTY WINDS WILL LIKELY CREATE BLOWING SNOW AND SLIGHT REDUCTION
TO VSBYS...BUT VSBYS SHUD REMAIN 6SM OR GREATER.
BEACHLER
//DISCUSSION...UPDATED 06Z...
IN THE WAKE OF THE SFC LOW/CLIPPER SYSTEM...THE WINDS HAVE BECOME
VERY LGT TO VRB AT TIMES. THE ABUNDANCE OF LINGERING NEAR SFC
MOISTURE WITH CLEARING SKIES ALOFT...AS ALLOWED PATCHY SHALLOW FOG
TO DEVELOP. THIS ONLY APPEARS TO BE TEMPORARY AS WINDS ARE
BEGINNING TO INCREASE FROM THE WEST/NORTHWEST. IR IMAGERY ALSO
INDICATES A THICK MID/UPR LVL CLOUD SHIELD ROTATING SOUTHEAST
TOWARDS NORTHERN IL/NORTHWEST IN AIRFIELDS. TIMING APPEARS TO
ARRIVE AT TAF SITES ARND 12Z AND STEADILY THICKENS. GUIDANCE HAS
BEEN CONSISTENT WITH CONSIDERABLE WIND DEVELOPING JUST AFT
DAYBREAK...WITH WINDS BECOMING WEST AND GUSTING AT TIMES TO 28KT.
IT DOES APPEARS THE GRADIENT BEGINS TO SLACKEN SOMEWHAT BY
18-20Z...THEN CLOSER TO 00Z THE FURTHER DIMINISHES WITH WINDS
BEGINNING TO TURN NORTHWESTERLY AGAIN. CLOUDS LINGER THROUGHOUT
THE AFTN/EVE TIMEFRAME...WITH SOME PATCHY MVFR CIGS DEVELOPING AFT
06Z MON.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN WIND DIR/SPEED/GUSTS.
* MEDIUM/HIGH CONFIDENCE IN TIMING OF GUSTS AND BLOWING SNOW
DEVELOPING.
* HIGH CONFIDENCE IN ALL OTHER ELEMENTS.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...CHANCE SNOW SHOWERS...MVFR POSSIBLE.
TUESDAY...MAINLY VFR.
WEDNESDAY THROUGH FRIDAY...PERIODIC CHANCE FOR SNOW SHOWERS AND
MVFR. OTHERWISE VFR.
MDB
&&
.MARINE...
307 PM CST
NO CHANGES WERE MADE TO THE ONGOING HEADLINES AS GALES ARE STILL
EXPECTED.
THE LOW IS OVER THE MID MISSISSIPPI RIVER VALLEY AND WHILE IT IS
FILLING SLOWER THAN PREVIOUSLY EXPECTED...IT IS STILL EXPECTED TO
FILL AS MOVES ACROSS SOUTHERN IL. A SECOND LOW IS MOVING INTO
NORTHERN QUEBEC AND ITS COLD FRONT WILL SINK SOUTH DOWN THE LAKE
SUNDAY AND SUNDAY NIGHT. AS THE GRADIENT TIGHTENS
TONIGHT...SOUTHWEST WINDS INCREASE TO GALES OVER THE NORTHERN HALF
TO THE LAKE. WINDS TURN WEST ACROSS THE LAKE AND INCREASE TO LOW END
GALES BY SUNDAY MORNING. WINDS DIMINISH SUNDAY AFTERNOON...AND MAY
COME DOWN BEFORE THE END OF THE GALE WARNING.
WINDS THEN TURN NORTH BEHIND THE FRONT SUNDAY NIGHT AND REMAIN AT 20
TO 25 KT...POSSIBLY UP TO 30 KT AT TIMES...THROUGH MONDAY NIGHT.
HIGH PRESSURE MOVES OVER THE UPPER PLAINS MONDAY NIGHT AND SLIDES
SOUTHEAST REACHING THE SE US WEDNESDAY. WINDS DIMINISH TUESDAY AND
BECOME WEST. GUIDANCE DIFFERS IN REGARDS TO THE PATTERN MID NEXT
WEEK. THE ECMWF FEATURES A DEEP LOW OVER THE LAKE WHILE THE GFS HAS
A WEAK SURFACE TROUGH. BOTH DO FEATURE A HIGH MOVING OVER THE
PLAINS. SO HAVE WINDS BECOMING NORTHWEST AND/OR NORTH WEDNESDAY
NIGHT...AND IF THE LOW IS DEEPER...WINDS COULD BE STRONGER. AS THE
HIGH PASSES TO THE SOUTH LATE NEXT WEEK...WINDS WEAKEN AND BECOME
WEST.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...3 AM SUNDAY TO 9
AM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745...9 AM SUNDAY TO 4 PM SUNDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868 UNTIL 3 PM SUNDAY.
GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 AM SUNDAY TO 3 PM
SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...3 AM SUNDAY TO 10
PM SUNDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
335 AM EST SUN JAN 19 2014
.SYNOPSIS...
ISSUED AT 1235 AM EST SUN JAN 19 2014
LOW TEMPERATURES TONIGHT WILL FALL INTO THE SINGLE DIGITS IN MOST
AREAS AS BRIEF CLEARING OCCURS. OTHERWISE STRONG SOUTHWEST WINDS
WILL DEVELOP BY LATE MORNING AND PERSIST THROUGH THE AFTERNOON
WITH GUSTS OF 35 TO 40 MPH POSSIBLE. THIS WILL LEAD TO SIGNIFICANT
BLOWING AND DRIFTING SNOW IN MANY AREAS. HIGHS THIS AFTERNOON WILL
RANGE UPPER 20S EAST TO THE LOWER 30S WEST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM EST SUN JAN 19 2014
EWD BREAKDOWN OF MEAN TROUGH THROUGH THE LAKES ON TAP THIS PD AS
CONUS HGT PATTN BRIEFLY RELAXES. HWVR THIS WILL YIELD PROBS TDA AS
LLJ RAMPS QUICKLY IN WAKE OF DEPARTING UPR JET LIFTING OUT THROUGH
THE ERN LAKES. PRIMARY QN IS HOW DEEP SFC BASED MIXED LYR CAN DVLP
OVERTOP DECENT SNOWPACK ACRS THE AREA. RUC ALG W/VARIOUS BUFR SNDG
DATA SUGGESTS SUFFICIENT MIXING TO TAP INTO MUCH HIGHER MOMENTUM AIR
JUST OFF THE DECK WITHIN A CORE OF 35KT FLW AT H95. THUS
W/POTENTIAL 35-40 MPH GUSTS...XPC SIG BLOWING/DRIFTING FM LATE
MORNING THROUGH MID AFTN BEFORE ABATING THIS EVENING.
SECONDARY CONCERNS EXIST THIS EVENING AHD OF NEXT CDFNT DROPPING SWD
ACRS THE LAKES. DEEPENING SFC BASED MOIST LYR ALG SFC CDFNT AND
SHALLOW ASCENT INDICATE A PD OF FZDZ PSBL BFR ADDNL SATURATION DEPTH
WITHIN COOLING LL COLUMN SPRTS -SHSN AND ADDED MENTION GIVEN GREATER
LIKELIHOOD OF FZDZ VS -SHSN OCCURRING UNTIL LT TONIGHT.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 333 AM EST SUN JAN 19 2014
VERY COLD PATTERN WILL PERSIST THIS PERIOD WITH REGION LOCKED IN
UNDER DEEP EASTERN CONUS LONGWAVE TROUGH AS UPPER RIDGE AMPLIFIES
ALONG THE WEST COAST OF NORTH AMERICA. NUMEROUS SHORTWAVES IN
PREVAILING NORTHWEST FLOW WILL BRING PERIODIC CHANCES FOR LIGHT
SNOW...WITH HEAVY LAKE EFFECT SNOW POSSIBLE IN WAKE OF SHORTWAVES
MON NIGHT/TUE AND AGAIN WED NIGHT/THU.
COLD ADVECTION WILL GRADUALLY DEEPEN BEHIND AN ARCTIC FRONT MON
WITH TEMPS STEADY/FALLING. STEEPENING LOW LEVEL LAPSE RATES IN
POST-FRONTAL ENVIRONMENT MAY SUPPORT A FEW FLURRIES OR LIGHT SNOW
SHOWERS...ESPECIALLY IN THE NORTHWEST WHERE LAKE ENHANCEMENT MAY
AFFORD SOME LIGHT ACCUMS. GUIDANCE IN DECENT AGREEMENT IN DROPPING
FIRST IN PARADE OF CLIPPER SYSTEMS AND SECONDARY SFC TROUGH THROUGH
LATE MONDAY AFTN/NIGHT. COULD SEE A QUICK 1-2" OF FLUFF WITH WAVE
GIVEN DEEP DGZ.
ATTENTION IN WAKE OF THIS WAVE WILL TURN TO BITTERLY COLD
TEMPERATURES (20 DEGREES BELOW NORMAL) TUE-WED AND POTENTIAL
SIGNIFICANT LAKE EFFECT SNOW EVENT MON NIGHT-TUE MORNING IN FAR NW
INDIANA/SW LOWER MI. SYNOPTIC FLOW LOCKS IN NORTHERLY DURING THIS
TIME WITH EXTREME OVER LAKE INSTABILITY AND FLOW DIRECTED PARALLEL
TO LONG AXIS OF LAKE LIKELY SUPPORTING STRONG CONVERGENCE. EXPECT
EXCELLENT SNOW GROWTH / RATIOS 30:1 OR SO / WITH OMEGA BULLSEYE IN
UPPER PORTION OF DGZ. MESOSCALE PROCESSES (MESOLOW DEVELOPMENT/LAND
BREEZE/AGGREGATE TROUGHING/ETC) WILL NO DOUBT MODULATE CONVECTIVE
LAYER TRAJECTORIES AND WHERE POTENTIAL INTENSE SINGLE BAND WILL SET
UP. WILL CONTINUE TO HIGHLIGHT THE THREAT FOR HEAVY LAKE EFFECT SNOW
IN THE HWO AND HOLD OFF ON ANY PERIOD 4 HEADLINES GIVEN NORMAL LAKE
EFFECT UNCERTAINTIES REGARDING PLACEMENT/TIMING...WITH BEST CHANCES
FOR WARNING LEVEL SNOWS/IMPACTS IN LA PORTE/STARKE/WESTERN ST JOE
IN/BERRIEN COUNTIES.
NEXT PV ANOMALY DIGS SOUTHEAST THROUGH THE LOWER GREAT LAKES WED-WED
EVE WITH NEXT OPPORTUNITY FOR WIDESPREAD LIGHT SNOW
ACCUMULATIONS...POSSIBLY FOLLOWED UP BY ANOTHER SIGNIFICANT LAKE
EFFECT/ENHANCED SNOW EVENT LATER WED NIGHT-THU. AND YEP...ANOTHER
SHORTWAVE AND REINFORCING SHOT OF ARCTIC AIR BY LATER FRI INTO SAT
PER LAST SEVERAL MODEL CYCLES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1231 AM EST SUN JAN 19 2014
SW DISTURBANCE OVR CNTRL OH AND ON THE WAY OUT AS LARGER SCALE LW
TROUGH BREAKS DOWN. RAPID CLRG OCCURRING ON WRN FLANK OF CLD SHIELD
YIELDING A SHARP DROP IN TEMPS AND FOSTERING DENSE GROUND FOG
DVLPMNT. HWVR SECONDARY BAND OF STRATUS WITHIN WK LL THERMAL TROUGH
WRAPPING QUICKLY SEWD OUT OF LWR MI SHLD STAVE OFF FOG PERSISTING
FOR MORE THAN FEW HOURS. OTRWS PRIMARY PROB THIS PD WILL BE RAPID
EWD DVLPMNT OF STG LLJ CORE IN WAKE OF DEPARTING UPR JET STREAK
LIFTING OUT THROUGH THE ERN LAKES. ADDED A LLWS MENTION W/06Z
ISSUANCE TO ACCOUNT FOR WHAT SHLD BE A TURBULENT BNDRY LYR AFT
SUNRISE AND XPC SWRLY SFC GUSTS AOA 30KTS PSBL TWD 18Z ASSUMING A
SUFFICIENT SFC BASED MIXED LYR CAN DVLP UNDERNEATH STRENGTHENING
INVERSION ALOFT. LOW BLOWING AND DRIFTING WILL BE PROBLEMATIC 15-21Z.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO MIDNIGHT EST
TONIGHT FOR LMZ043-046.
&&
$$
SYNOPSIS...T
SHORT TERM...T
LONG TERM...STEINWEDEL
AVIATION...T
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1235 AM EST SUN JAN 19 2014
.SYNOPSIS...
ISSUED AT 1235 AM EST SUN JAN 19 2014
LOW TEMPERATURES TONIGHT WILL FALL INTO THE SINGLE DIGITS IN MOST
AREAS AS BRIEF CLEARING OCCURS. OTHERWISE STRONG SOUTHWEST WINDS
WILL DEVELOP BY LATE MORNING AND PERSIST THROUGH THE AFTERNOON
WITH GUSTS OF 35 TO 40 MPH POSSIBLE. THIS WILL LEAD TO SIGNIFICANT
BLOWING AND DRIFTING SNOW IN MANY AREAS. HIGHS THIS AFTERNOON WILL
RANGE UPPER 20S EAST TO THE LOWER 30S WEST.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 320 PM EST SAT JAN 18 2014
TWO CHALLENGES IN THE SHORT TERM: DURATION/INTENSITY/AMOUNT OF SNOW
AND MIN TEMPERATURE TONIGHT/SUNDAY MORNING.
THE CLIPPER SYSTEM IS WELL FORECAST BY THE MODELS THIS AFTERNOON AND
MORNING INITIALIZATIONS WERE NEARLY SPOT ON. LATEST SATELLITE/RADAR
DATA SHOW THE DEEPENING WAVE AND ASSOCIATED WARM SECTOR ASSENT ON
THE EAST AND NORTHEAST AREA IS HOLDING TOGETHER WELL. EXPECT TO SEE
THE LEADING EDGE OF THE SNOW ACROSS THE SOUTHWEST PORTION OF THE CWA
BETWEEN 2-4 PM EST AND THIS WILL SHIFT NORTH AND EAST DURING THE
EVENING. AM CONCERNED THAT THE DRIER AIR IS STARTING TO WRAP AROUND
THE LOW AND THIS SHOULD BE ENOUGH TO CREATE A VERY NARROW
PRECIPITATION BAND. AS MODELS ARE STARTING TO SHOW...THIS WILL BE A
RAPIDLY MOVING SYSTEM AND WHILE THERE ARE HINTS OF FAVORABLE
FRONTOGENETIC FORCING...THE RAPID TRANSITORY NATURE WILL RESULT
GENERAL AREAS OF SNOWFALL WITH EMBEDDED BANDS OF ENHANCED SNOWFALL.
BY MIDNIGHT...THE SYSTEM WILL HAVE BECOME MORE OF AN OPEN WAVE AND
THIS WILL BRING THE SNOWFALL TO A QUICK END FROM WEST TO EAST. MODEL
SOUNDINGS SUGGEST THAT CLOUDS/STRATUS WILL PERSIST OVER MUCH OF THE
AREA...BUT THIS LEADS TO THE SECOND CHALLENGE FOR THE PERIOD. AS THE
TROF OPENS UP AND THE FLOW TURNS MORE WESTERLY...THE POTENTIAL FOR
CLEARING SKIES IS BECOMING MORE LIKELY. AS A RESULT HAVE TRIMMED THE
OVERNIGHT LOWS A FEW DEGREES. THE RUC AND LOCAL WRF ARE BY FAR THE
COOLEST OF THE MODELS AT THIS TIME AND GIVEN THE CLEARING NOTED IN
THE WAKE OF THE SYSTEM...FEEL COMPELLED TO LEAN TOWARD THE COOLER
SOLUTIONS. ONLY A MINOR DOWNWARD ADJUSTMENT MADE.
EXPECT TO SEE A FEW LAKE ENHANCED SNOW SHOWERS DURING THE DAY SUNDAY
WITH FAVORED AREAS NEAR THE SHORELINE AND LIGHT SNOW SHOWERS ALONG
AND NORTH OF US-30.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 320 PM EST SAT JAN 18 2014
ONCE AGAIN VERY FEW CHANGES NEEDED TO LONG TERM WITH PERSISTENT BUT
ACTIVE PATTERN. LONG WAVE TROUGH REMAINS ANCHORED OVER THE GREAT
LAKES WITH LARGE SCALE RIDGE OVER WEST COAST. DEEP NORTHERLY FLOW
WILL KEEP THE POLAR EXPRESS OF SHORT WAVES ON TRACK WITH SEVERAL
WAVES OVER THE NEXT WEEK. LAKE EFFECT WILL BE ONGOING FOR ABOUT THE
ENTIRE PERIOD BUT BACKING AND VEERING WINDS MAKE BAND ORIENTATION
AND PLACEMENT DIFFICULT AT BEST AT THIS TIME RANGE.
NEXT ARCTIC BOUNDARY STILL SET TO PLUNGE SOUTH ACROSS THE AREA ON
MONDAY. EARLY MORNING HIGHS EXPECTED WITH WINDS BECOMING NORTH
THROUGH THE DAY AND COLD AIR ADVECTION DEEPENING. WILL CONTINUE WITH
LOW CHANCE POPS FOR FLURRIES/LIGHT SNOW SHOWERS AS COLD AIR DEEPENS.
LAKE EFFECT TO LIKELY BE SLOW AND LIGHT AT FIRST BUT AS SECONDARY
FRONT AND COLDER AIR MOVE IN LATER MONDAY AND ESPECIALLY MONDAY
NIGHT INTO TUESDAY...SHOULD SEE THE LAKE EFFECT MACHINE CRANK INTO
FULL GEAR. STILL EXPECT A SIGNIFICANT SINGLE BAND SOMEWHERE BETWEEN
EXTREME SOUTHWEST BERRIEN COUNTY AND PORTER COUNTY IN NW INDIANA.
THIS WILL DEPEND ON STRENGTH OF CONVERGENCE. UPSTREAM CONDITIONING
EXPECTED WITH LONG FETCH AND EXTREME DELTA TS SO SIGNIFICANT
ACCUMULATIONS LIKELY...JUST A QUESTION OF EXACTLY WHERE. STILL NEED
A FEW MORE MODEL ITERATIONS BEFORE HIGHER RESOLUTION GUIDANCE BEGINS
TO PICK UP THESE PERIODS.
REST OF THE WEEK TO SEE A CONTINUATION OF MEANDERING LAKE EFFECT
BANDS AND COLD TEMPS. AS WE HAVE BEEN DISCUSSING...HIGHS IN SINGLE
DIGITS TO TEENS WITH LOWS AROUND ZERO TO 6 BELOW RIGHT NOW. REALLY
EXPECT SOME COLDER READINGS...ESPECIALLY IF WE DECOUPLE AND ARE
CLEAR TUE NIGHT WITH HIGH PRESSURE MOVING THROUGH AND FRESH SNOWPACK.
COULD SEE LOWS BOTTOM OUT IN RURAL AREAS IN THE 10 TO 15 BELOW RANGE
AGAIN IF IDEAL RADIATIONAL CONDITIONS DEVELOP. FOR NOW STAYED ON THE
CONSERVATIVE SIDE OF COLDER BLENDS AROUND 5 BELOW.
YET ANOTHER SHORT WAVE AND REINFORCED SHOT OF COLD AIR AROUND MID
WEEK WILL KEEP CHANCES FOR SNOW SHOWERS GOING. MEDIUM RANGE MODELS
HINT AT ANOTHER POSSIBLE SINGLE BAND BEHIND THIS WAVE. LOWS THU
NIGHT HAVE POTENTIAL TO GO EVEN LOWER THAN CURRENT FCST LOWS IF HIGH
PRESSURE SLIDES IN AND WE DECOUPLE AGAIN.
SLIGHT MODERATION IN MODELS BEING SHOWN FOR DAY 7 BEFORE NEXT POLAR
EXPRESS SHORT WAVE MOVES IN EARLY IN WEEK TWO PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1231 AM EST SUN JAN 19 2014
SW DISTURBANCE OVR CNTRL OH AND ON THE WAY OUT AS LARGER SCALE LW
TROUGH BREAKS DOWN. RAPID CLRG OCCURRING ON WRN FLANK OF CLD SHIELD
YIELDING A SHARP DROP IN TEMPS AND FOSTERING DENSE GROUND FOG
DVLPMNT. HWVR SECONDARY BAND OF STRATUS WITHIN WK LL THERMAL TROUGH
WRAPPING QUICKLY SEWD OUT OF LWR MI SHLD STAVE OFF FOG PERSISTING
FOR MORE THAN FEW HOURS. OTRWS PRIMARY PROB THIS PD WILL BE RAPID
EWD DVLPMNT OF STG LLJ CORE IN WAKE OF DEPARTING UPR JET STREAK
LIFTING OUT THROUGH THE ERN LAKES. ADDED A LLWS MENTION W/06Z
ISSUANCE TO ACCOUNT FOR WHAT SHLD BE A TURBULENT BNDRY LYR AFT
SUNRISE AND XPC SWRLY SFC GUSTS AOA 30KTS PSBL TWD 18Z ASSUMING A
SUFFICIENT SFC BASED MIXED LYR CAN DVLP UNDERNEATH STRENGTHENING
INVERSION ALOFT. LOW BLOWING AND DRIFTING WILL BE PROBLEMATIC 15-21Z.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO MIDNIGHT EST
TONIGHT FOR LMZ043-046.
&&
$$
SYNOPSIS...T
SHORT TERM...LASHLEY
LONG TERM...LEWIS
AVIATION...T
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
312 AM EST Sun Jan 19 2014
.SHORT TERM (Now through Monday)...
Issued at 310 AM EST Sun Jan 19 2014
Our uneventful clipper system is quickly tracking east. Guidance 24
hours ago was in good agreement that 1-2 inches of snow was likely
across portions of the forecast area, thus warranting the issuance
of a Winter Weather Advisory. The rather poor job of numerical
guidance handling the dry lower atmosphere, the warm-air advection
ahead of the surface low, and certainly my interpretation of this
data and past trends this winter did not produce a good forecast.
The lingering dry lower atmosphere severely cut down our snow
chances late yesterday afternoon and evening. Then, the warm-air
advection ahead of the system overnight boosted temperatures into
the middle 30s over snowpack regions, with upper 30s and lower 40s
across southern Kentucky. Precipitation that was originally forecast
to be snow was now falling in the form of rain. There was some snow
observed, so it was not all rain, but a large majority was liquid.
Pretty disappointing to say the least.
Breezy/gusty west and northwest winds are behind the precip early
this morning, with plenty of time to help dry any pavement that
happened to get wet before any freezing temperatures arrive later
this morning. So, believe there will not be any roadway concerns
this morning from this system. With this, have cancelled the Winter
Weather Advisory. However, remnant slick roads from the previous
snowfall are still possible.
As this system exits this morning, we will enter a dry stretch for
the remainder of the short-term period. The rest of the day will
feature clearing skies from west to east and will remain mostly
clear tonight. West-northwest winds will transition to southwesterly
breezes by the afternoon and remain that way through tonight.
Temperatures should range from around 30 across our northeast to
upper 30s across our southwest CWA. With steady southwest winds
tonight in the 10-15 mph range, expect temperatures to stay up a
bit, even with clear skies. Temperatures should range from middle
20s to lower 30s. Clouds will gradually increase from the north
Monday as a cold front drops south into the Ohio Valley. Still
expecting a dry day and temperatures will edge up a few degrees,
with middle 30s to middle 40s on tap.
.LONG TERM (Monday Night through Saturday)...
Issued at 305 AM EST Sun Jan 19 2014
Broad eastern CONUS trof will dominate the upper pattern through
most of the coming week. Main challenge will be the timing and
sensible weather impacts of any in a series of Clippers that will
swing through the base of this trough, and the extent of the Arctic
intrusions behind each system.
First Clipper swings through late Monday night into Tuesday morning.
Surface reflection is weak, but models show the upper impulse on the
back end becoming a bit sharper as it digs into the Ohio Valley.
Therefore went for the more bullish POPs in the NAM MOS and will
carry a solid chance of snow showers across roughly the northeastern
half of the area. Temp curve has been massaged to show a slow fall
Monday night, and little or no daytime recovery on Tuesday as 850mb
temps plunge to around -18C.
Unseasonably cold air mass will take over for the remainder of the
work week, with another Clipper to reinforce the Arctic high on
Wednesday night. This system looks like more of a glancing blow, so
for now will limit POPs to a slight chance for snow showers across
the Bluegrass. Thursday temps will be similar to Tuesday, but with a
colder start and decent NW winds as the high builds in, morning wind
chills will be near or below zero over southern Indiana and parts of
north central Kentucky.
Thermal trof looks progressive enough that temps will begin to
recover by Friday, but will not really approach seasonal normals
until Saturday, when a WSW gradient tightens up between the surface
high along the Gulf coast, and the next Clipper diving out of the
Upper Midwest.
&&
.AVIATION (06Z TAF Update)...
Updated at 1235 AM EST Sun Jan 19 2014
The final wave of precip is tracking eastward across Kentucky. With
areal coverage decreasing, will just run with VCSH early this
morning. Most of the precip is falling as rain, with a few obs of
snow, but not many. So, no impacts are expected with this precip.
However, LAMP and RAP guidance as well as upstream obs indicate cigs
will drop to MVFR post precip at SDF and LEX, and gradually improve
to VFR through the morning hours. Still believe BWG will remain VFR
through the period. Southwest winds will become breezy and
transition to westerly through the early morning hours, then back to
southwesterly after daybreak and remain breezy through the afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Short Term........MJP
Long Term.........RAS
Aviation..........MJP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1255 AM EST SUN JAN 19 2014
.UPDATE...
ISSUED AT 1255 AM EST SUN JAN 19 2014
HAVE UPDATED THE FORECAST TO FURTHER TAKE DOWN SNOW AMOUNTS...POPS...
AND DEWPOINTS. VERY DRY AIR...WITH DEWPOINTS RUNNING 5 TO 7 DEGREES
BELOW THE LATEST CONSSHORT GUIDANCE...HAVE SOPPED UP ANY PCPN FALLING
OVER THE AREA DURING THE EVENING AND INTO THE OVERNIGHT. THE MAIN
THRUST OF PCPN...STILL AWFULLY LIGHT ON THE MOSAIC RADAR...IS JUST
NOW APPROACHING THE SOUTHWEST PARTS OF THE CWA. THE HRRR AND LATEST
NAM12 KEEP THE QPF WITH THIS QUITE LIMITED. IN ADDITION...
TEMPERATURES ARE RUNNING 5 DEGREES OR SO ABOVE ALL GUIDANCE ALSO
ADDING P-TYPE ISSUES TO ONGOING CONCERNS FOR ANY ACCUMULATING SNOW
TONIGHT. THESE ADJUSTMENTS HAVE BEEN MADE TO THE GRIDS...AND BARRING
ANY UPTICK IN PCPN COVERAGE...OR SNOW REPORTS OF SUBSTANCE...AS THIS
WAVE MOVES EAST WILL BE DROPPING THE ADVISORIES WITH THE NEXT UPDATE.
WILL STILL CARRY AN SPS THROUGH MIDDAY...THOUGH...FOR LINGERING
CONCERNS OF A DUSTING TO HALF INCH OF SNOW FALLING ON ROADS THAT ARE
PROBABLY SUBFREEZING IN PLACES. ALL IN ALL THIS SYSTEM...SIMILAR TO
THE ONE LAST WEEK...HAS BEEN A BUST SO FAR. THESE UPDATED GRIDS HAVE
BEEN SENT TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 859 PM EST SAT JAN 18 2014
UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
TRENDS. SOME SNOW HAS BEEN REPORTED NORTH OF I 64. BASED ON THE NCEP
ANALYSIS...THERE IS A WARM FRONT NORTH OF A LINE FROM MOUNT STERLING
TO PIKEVILLE. THERE IS A LOW JUST NORTH OF DECATUR ILLINOIS WITH A
COLD FRONT EXTENDING SOUTH THOUGH THE TIP OF ILLINOIS INTO SOUTH
CENTRAL ARKANSAS. THIS LOW IS EXPECTED TO TRACK DUE EAST...SO IT WILL
STAY TO THE NORTH OF THE AREA. THE COLD FRONT ASSOCIATED WITH THIS
SYSTEM SHOULD BE MOVING ACROSS EASTERN KENTUCKY FROM 1 AM THROUGH 6
AM. THIS IS WHEN THE MOST WIDESPREAD SNOW SHOULD BE MOVING ACROSS THE
AREA. RIGHT NOW JUST EXPECTING UP TO ONE INCH OF SNOW OVER MOST
LOCATIONS. THE MOUNTAIN AREAS NEAR THE VIRGINIA BORDER MAY SEE UP TO
TWO INCHES OF SNOW.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 346 PM EST SAT JAN 18 2014
MODELS ARE IN GOOD AGREEMENT CONCERNING THE PERIOD...WITH THE MAIN
FEATURE BEING A CLIPPER TYPE SYSTEM MOVING THROUGH TONIGHT. THE
SURFACE LOW WILL TRACK BY TO OUR NORTH...NEAR OR JUST NORTH OF THE
OHIO RIVER. A TRACK TO OUR NORTH IS CLIMATOLOGICALLY UNFAVORABLE FOR
SNOW OF SIGNIFICANCE...EVEN WITH A CLIPPER SYSTEM. MODELS DO GENERATE
PRECIP TONIGHT IN THE WARM AIR ADVECTION REGIME AHEAD OF THE COLD
FRONT SOUTH OF THE LOW...BUT AMOUNTS ARE LIGHT. PLUS...TEMPS IN THE
FAR SOUTHERN PART OF THE AREA ARE ABOVE FREEZING THIS AFTERNOON...
WITH MOS DATA AND THE RAW NAM SHOWING ABOVE FREEZING TEMPS FOR PART
OF THE NIGHT. THINK THAT ACCUMULATIONS WILL GENERALLY BE AN INCH OR
LESS. IF AN ADVISORY HAD NOT BEEN INHERITED...ONE WOULD NOT BE ISSUED
AT THIS POINT. HOWEVER...FOR CANCELING AN ADVISORY THAT IS ALREADY
IN PLACE...THE BURDEN OF PROOF TENDS TO BE ON SHOWING THAT THERE IS
VERY LITTLE CHANCE THAT ANY PROBLEMS WILL RESULT...SO AS NOT TO
RESULT IN A FLIP/FLOP FORECAST. THAT BEING SAID...WILL LEAVE IT IN
PLACE...AND IF IT DOES NOT LOOK PROMISING AS THE SYSTEM ARRIVES...
EVENING OR MID SHIFT MAY BE ABLE TO CANCEL IT.
AS THE SURFACE SYSTEM AND THE ASSOCIATED UPPER TROUGH PULL OUT ON
SUNDAY...ALL INDICATIONS ARE THAT CLOUDS WILL BREAK UP...WITH FAIR
WEATHER THEN PERSISTING THROUGH SUNDAY NIGHT. IN FACT...WARM AIR
ADVECTION BEGINS BY SUNDAY NIGHT AS THE SURFACE PRESSURE GRADIENT
TIGHTENS AHEAD OF A COLD FRONT DROPPING SOUTH THROUGH THE NORTH
CENTRAL AND NORTHEAST CONUS. A QUESTION TO BE ANSWERED IS WHETHER OR
NOT OUR VALLEYS CAN DECOUPLE ON SUNDAY NIGHT. AT THIS POINT HAVE
ALLOWED FOR A BIT OF A RIDGE/VALLEY LOW TEMPERATURE DIFFERENCE...BUT
FURTHER ADJUSTMENT WILL BE NEEDED.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 414 PM EST SAT JAN 18 2014
COLD WEATHER WITH OCCASIONAL BOUTS OF LIGHT SNOW CONTINUE TO LOOK
LIKE THE RULE FOR THE OHIO AND TENNESSEE VALLEYS FOR NEXT WEEK...AS A
PERSISTENT TROUGH LINGERS ACROSS THE EASTERN CONUS...WITH PROGRESSIVE
SHORT WAVES TRAVERSING THE FLOW FROM TIME TO TIME. TIMING OF THESE
MINOR IMPULSES REMAINS CHALLENGING THIS FAR OUT...SO STUCK FAIRLY
CLOSE TO A BLEND OF THE LATEST GUIDANCE AND INHERITED FORECAST.
MONDAY WILL START OUT DRY ACROSS THE AREA...WITH THE FIRST WAVE
APPROACHING AND MOVING THROUGH MONDAY NIGHT INTO TUESDAY...BRINGING
THE THREAT OF LIGHT SNOW AND SNOW SHOWERS. A GOOD SHOT OF COLDER AIR
WILL ARRIVE IN THE WAKE OF THE PASSING COLD FRONT. HIGHS ON TUESDAY
MAY WIND UP BEING MORE IN THE MORNING IF THE TIMING HOLDS. LOWS BY
WEDNESDAY MORNING WILL GET DOWN INTO THE SINGLE DIGITS FOR MOST OF
THE VALLEYS.
DRY WEATHER WILL THEN HOLD FROM AT LEAST TUESDAY NIGHT THROUGH
WEDNESDAY...AND PERHAPS BEYOND...AS THE MODELS HAVE TRENDED A BIT
DRIER WITH THE NEXT SHORT WAVE THAT LOOKS TO BRUSH OUR AREA WEDNESDAY
NIGHT INTO THURSDAY. WILL HOLD ONTO SOME SLIGHT CHANCE POPS FOR
NOW...WITH MAINLY DRY WEATHER EXPECTED ONCE AGAIN FRIDAY AND
SATURDAY. TEMPERATURES WILL REMAIN WELL BELOW NORMAL THROUGH THE END
OF THE WORK WEEK...WITH HIGHS FROM WEDNESDAY THROUGH FRIDAY MAINLY IN
THE 20S...AND LOWS RANGING FROM THE SINGLE DIGITS TO THE TEENS.
READINGS WILL THEN MODIFY A BIT INTO THIS WEEKEND...WITH HIGHS
RETURNING TO ABOVE FREEZING.
LOOKING TOWARDS THE LATTER HALF OF NEXT WEEKEND...THE MODELS HAD BEEN
PRETTY CONSISTENT IN BRINGING ANOTHER ARCTIC AIR INTRUSION PRETTY FAR
SOUTH ONCE AGAIN. THE LATEST 12Z RUNS HAVE BACKED OFF ON THIS
SCENARIO...KEEPING IT MORE CONFINED TO THE NORTHERN STATES...WITH
TEMPERATURES ACROSS OUR AREA LIKELY NOT GETTING AS COLD AS WHAT WE
WILL SEE FOR THE MIDDLE OF THIS COMING WORKWEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1250 AM EST SUN JAN 19 2014
MOSTLY VFR CONDITIONS CAN BE EXPECTED THROUGH THE AVN FORECAST...
THOUGH THERE LIKELY WILL BE A PERIOD OF MVFR FROM BOTH CIGS AND VIS
WITH THE REMNANT OF THE PCPN COMING THROUGH THE AREA OVER THE NEXT
SEVERAL HOURS. HAVE HANDLED THIS WITH A TEMPO GROUP IN THE TAFS. THE
LOWER CIGS WILL LINGER...IN THE WAKE OF THE FLEETING SNOW...INTO MID
MORNING BEFORE THESE TOO BREAK UP FOR VFR CONDITIONS INTO THE REST OF
DAY...SUNDAY. WINDS WILL SWITCH TO THE WEST FOR TIME AS THE LOW
PASSES WITH A POTENTIAL FOR GUSTS TO 15 KTS OR SO...BEFORE THEY SWING
BACK TO THE SOUTHWEST BY SUNDAY AFTERNOON AT AROUND 10 KTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR KYZ044-
050>052-058>060-068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...GREIF
SHORT TERM...HAL
LONG TERM...GEOGERIAN
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1235 AM EST Sun Jan 19 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 939 PM EST Sat Jan 18 2014
Combination of dry air and warm temperatures at the surface has led
to no appreciable snowfall across the area. In fact, a few snow
flurries has been the most that we`ve seen this evening. However,
we have a batch of rain/snow showers out to the west that is pushing
through southern IL. These will pass through southern IN and
central KY overnight.
Thermal profiles still show some warmer air near the surface and we
still have temperatures out to our west in the upper 30s to the
lower 40s. So as this shower activity pushes in, it will probably
start off as rain showers or a rain/snow mix that transitions over
to snow during the overnight period. With the expected mix,
snowfall accumulations overnight look less...with a dusting to
perhaps as much as an inch in some spots. With temperatures falling
into the upper 20s by morning, we could have some travel problems
late tonight and Sunday morning.
With regards to the advisory...after coordinating with WFO JKL, plan
on leaving the advisory up for impact sake. The rain/snow mix going
over to snow late will probably lead to some very minor
accumulations. That, along with the expected temperature drop could
lead to some slick spots overnight and towards dawn Sunday.
We will have updated forecast products and grids out shortly.
Update issued 622 PM EST Sat Jan 18 2014
Model proximity soundings, ACARS soundings and radar reflectivity
trends show that antecedent dry airmass in place is really eating up
the precipitation band that has been working in from the west. The
column is gradually saturating from the top downward, but by the
time this occurs in the I-65 corridor, much of the precipitation
will be off to the east. In general, it looks like we`ll probably
see a little light snow this evening across central KY and southeast
Indiana, but the main snows will be located well north of here.
Overall, not expecting much in the way of accumulation this evening
with this initial band moving through. A dusting to a couple of
tenths of an inch at best looks more likely. With temperatures
staying around freezing, we could have some slick spots develop this
evening...mainly NE of a line from near Fort Knox to London KY.
Though with the clipper moving north of us, some light warm air
advection may push temperatures a degree or two higher this evening
before more nocturnal cooling commences later this evening.
Some additional snow shower activity over in the St. Louis area will
move into the region later tonight. These snow showers will be
scattered in nature and may produce another light dusting to a
couple of tenths of an inch of accumulation. While model soundings
do show the potential for convective snows, it should be noted that
the moisture profiles are quite shallow. Thus, these showers will
not be as efficient as those we saw Friday morning. However, we
will continue to monitor this activity through the evening hours.
.SHORT TERM (Now through Sunday Night)...
Issued at 235 PM EST Sat Jan 18 2014
...A Round of Light Snow, Followed by Snow Showers Later This
Evening...
The main focus will be on the Clipper system moving through the CWA
later this evening and overnight. Overall, am going to downplay the
event a bit as main band of snow associated with the warm conveyor
belt wrapping into the system will quickly move through with only
light to briefly moderate snow. This band can currently be seen in
southern Illinois and watch for it to swing into southern IN and
north central KY over the next few hours. This initial snowfall will
waste some time saturating the column as it has some dry air to
overcome. Therefore, only expect around a half an inch up to 1 inch
across southern IN and north central Kentucky as it slides through.
Best timing with this band will be 4-7 PM EST west of I-65 and 7-10
PM EST east of I-65.
Thereafter, really just expect scattered snow showers through the
rest of the evening into the overnight, with only light additional
accumulations with each shower. Some of the forecast soundings show
showers taking on a bit more of a convective look later tonight,
however deeper moisture will already be exiting so don`t think the
showers will be quite as efficient as we saw yesterday. Do
anticipate some brief moderate snow and reduced visibilities in any of
these showers if traveling.
Overall, have bumped snow totals down, but will leave the Advisory
in place for a couple of reasons. 1.) We still expect a quick
hitting band of snow that could produce periods of moderate snowfall
and accumulations up to 1", initially. This could lead to some
travel problems. 2.) Lingering snow showers into the overnight may
continue to provide additional light accumulations. The most likely
locations with the best shot to see 1" to locally 2" will be across
Orange to Jefferson county Indiana, then over to Harrison county
Kentucky. South of this line, everyone else should expect up to 1".
Main reason to leave our eastern counties in the Advisory will be
for the upslope enhanced snow showers later this evening where up to
1" will be possible.
Did want to mention that areas outside of the Advisory will also see
a mix of rain/snow initially and will change to scattered snow
showers later this evening. A dusting up to a half an inch will be
possible.
Otherwise, surface temperatures have warmed into the mid and upper
20s in most spots, with several obs in south central KY in the
lower 30s. These temps will continue to slowly rise over the next
few hours on a warm advective component, and despite the heavy cloud
cover. Temperatures will likely hover in the low 30s for much of the
overnight as we stay in the warm sector of the clipper until just
after Midnight. Temperatures will begin to fall back into the upper
20s toward dawn.
May see a few lingering flurries in our east to start the day on
Sunday, however expect skies to clear pretty quickly from west to
east thereafter. Highs tomorrow will be somewhat dependent on how
much snow falls or snowpack remains, but in general expect low 30s
north to mid and upper 30s central and south.
Tomorrow night will feature mostly clear skies and steady SW winds.
This will help keep the boundary layer mixy enough for lows to only
drop into the upper 20s to around 30. Colder temperatures may be
possible dependent on lingering snow pack and decoupled valleys.
.LONG TERM (Monday through Saturday)...
Issued at 305 PM EST Sat Jan 18 2014
A broad upper level trough with embedded clippers/cold air
intrusions will continue over the Midwest through much of the long
term period. However, there is more uncertainty for the Thurs-Sat
forecast as to how far south the broad upper trough will remain and
the exact southern extent of cold air intrusions.
For Mon night/Tues, another clipper system looks to quickly swing
through the region potentially bringing some light snow accums.
Forcing with this clipper doesn`t look quite a good as in previous
clippers so snow accums may be limited to a half inch or less.
Behind this clipper, cold air certainly looks to follow with breezy
conditions on Tues. While Monday`s highs will likely warm into the
upper 30s to mid 40s on a southwesterly flow, Tuesday`s highs will
likely be limited to the low to mid 20s over much of the area.
Wed/Wed night another quick hitting clipper looks to pass mainly to
the north of our region but 12Z ensembles do indicate a decent
signal for some isld snow showers so will include a 20% chance with
this forecast package over southern Indiana, northern KY, and east
central KY. This will re-enforce cold air over the region with
another breezy, cold day expected on Thurs. Highs on Wed should
range throughout the 20s with highs on Thurs dropping back into the
upper teens to mid 20s.
Low temps will range through the single digits to mid teens Wed
morning through Friday morning.
For Thurs-Sat the forecast becomes a little more uncertain as models
vary on if the western ridge will break down some as an upper low
potentially gets trapped off the southern California coast. These
features may cause our upstream trough to weaken/lift and push east
a smidge. Thus, recent models have generally come in drier and
somewhat warmer for next weekend. Will continue a dry forecast and
cautiously increase temps into the upper 20s/30s for Fri and 30s to
lower 40s for Saturday. GFS and ECMWF op models really disagree on
if we get a colder air intrusion at the beginning of next week. Stay
tuned!
&&
.AVIATION (06Z TAF Update)...
Updated at 1235 AM EST Sun Jan 19 2014
The final wave of precip is tracking eastward across Kentucky. With
areal coverage decreasing, will just run with VCSH early this
morning. Most of the precip is falling as rain, with a few obs of
snow, but not many. So, no impacts are expected with this precip.
However, LAMP and RAP guidance as well as upstream obs indicate cigs
will drop to MVFR post precip at SDF and LEX, and gradually improve
to VFR through the morning hours. Still believe BWG will remain VFR
through the period. Southwest winds will become breezy and
transition to westerly through the early morning hours, then back to
southwesterly after daybreak and remain breezy through the afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WINTER WEATHER ADVISORY until 7 AM EST /6 AM CST/ this morning
FOR KYZ025-028>043-045>049-053>057-064>067-077-078-082.
IN...WINTER WEATHER ADVISORY until 7 AM EST /6 AM CST/ this morning
FOR INZ076>079-083-084-090>092.
&&
$$
Update.........MJ
Short Term.....BJS
Long Term......AMS
Aviation.......MJP
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1152 PM EST SAT JAN 18 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 446 PM EST SAT JAN 18 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW VERY FAMILIAR UPR
AIR PATTERN WITH DEEP TROF OVER CENTRAL/ERN NAMERICA DOWNSTREAM OF
HI AMPLITUDE RDG OVER THE W. ALTHOUGH SOME LO CLDS/LGT SHSN OR
FLURRIES WERE ARND INTO EARLY AFTN WITH LLVL MSTR TRAPPED UNDER LO
INVRN SHOWN ON THE 12Z INL/GRB RAOBS...ARRIVAL OF DRIER LLVL AIR
DEPICTED ON THE INL RAOB HAS TENDED TO DIMINISH THIS LO CLD.
OTRW...THERE IS RELATIVELY QUIET WX OVER UPR MI TDAY GIVEN SHRTWV
RDG/MID LVL DRY AIR SHOWN ON THE RAOBS DOMINATING THE UPR LKS TO THE
N OF POTENT CLIPPER SHRTWV DIGGING SEWD THRU THE MIDWEST. NEXT
DISTURBANCE IN THE NEVER ENDING PARADE OF CLIPPER SHRTWVS IS NOW
DIGGING SSEWD THRU NRN MANITOBA AND INTO FAR NW ONTARIO. FAIRLY
SHARP PRES FALLS AND EXTENSIVE CLD COVER ARE EVIDENT IN MANITOBA AND
NW ONTARIO AHEAD OF THIS SHRTWV.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE IMPACT ON POPS/WINDS/
BLSN OF SHRTWV DIGGING SEWD INTO NW ONTARIO AND TEMPS TRENDS TNGT.
TNGT...SHRTWV/ACCOMPANYING SFC LO OVER NW ONTARIO THIS EVNG ARE
PROGGED TO MOVE TO NEAR JAMES BAY BY 12Z SUN...WITH ATTENDANT COLD
FNT REACHING THE KEWEENAW TOWARD 12Z. MODELS INDICATE THE SFC LO WL
DEEPEN FM ABOUT 995MB THIS EVNG TO 985MB ON SUN MRNG AS THE SHRTWV
DIGS INTO THE MEAN UPR TROF. ALTHOUGH BULK OF THE ACCOMPANYING
DPVA/DEEP LYR QVECTOR CNVGC ARE PROGGED TO SWING THRU ONTARIO AND N
OF THE CWA IN THE 06Z-12Z TIME FRAME...SOME OF THIS FORCING DOES
IMPACT UPR MI. MODELS INDICATE FAIRLY DEEP MOISTENING...WHICH IS
BACKED UP BY COLDER CLD TOPS AND UPSTREAM OBS IN NRN MANITOBA AND
SASKATCHEWAN SHOWING FAIRLY WDSPRD LGT SN EVEN ON THE ACYC SIDE OF
SHRTWV TRACK. GIVEN THESE OBS...SUSPECT THE HIER QPF UP TO 0.20 INCH
OVER THE W THRU 12Z SUN SHOWN BY THE 12Z NAM/REGIONAL GEM MAY BE ON
THE RIGHT TRACK DESPITE MARGINAL H85 TEMPS FOR LES. STRENGTHENING
UPSLOPE W-SW FLOW WOULD ALSO TEND TO ENHANCE PCPN TOTALS IN THIS
AREA. THE COMBINATION OF THE FALLING SN AND GUSTY WINDS OVER THE
MORE EXPOSED KEWEENAW PENINSULA ACCENTUATED BY H925 WINDS UP TO
35-40 KTS WL LIKELY CAUSE BLSN/SHARPLY REDUCED VSBY. PLAN TO REISSUE
SPS FOR THIS AREA. DOWNSLOPE NATURE OF WSW FLOW WL TEND TO LIMIT QPF
OVER THE CNTRL ZNS. AS FOR TEMPS...READINGS MAY FALL OFF FAIRLY
QUICKLY EARLY UNDER CLR-PCLDY SKIES...BUT COMBINATION OF INCRSG
CLDS/WINDS BY LATE EVNG SHOULD CAUSE TEMPS TO REBOUND...ESPECIALLY
IN THE DOWNSLOPE AREAS NEAR LK SUP.
SUN...AS SHRTWV/SFC LO MOVE INTO QUEBEC...ATTENDANT COLD FNT WL
CROSS UPR MI...CLRG MENOMINEE ARND 18Z. THERE MAY BE A PERIOD OF
HEAVIER SHSN/BLSN NEAR LK SUP E OF MQT ACCOMPANYING THE FROPA WITH
WSHFT TO THE NW AND GUSTY WINDS/H925 WINDS STILL NEAR 30 KTS. OPTED
TO INCLUDE THIS AREA IN SPS ISSUED FOR THE NW CWA TNGT. ALTHOUGH
FCST NNW FLOW IN THE WAKE OF THIS FROPA AND H85 TEMPS FALLING TO
ARND -20C OVER THE NRN TIER BY 00Z MON WL BE FVRBL FOR LES IN THE
FAVORED SN BELTS...DEEP LYR QVECTOR DVGC/SUBSIDENCE IN THE WAKE OF
SHRTWV PASSAGE THAT IS FCST TO SHARPEN INVRN ARND 3K FT WL TEND TO
LIMIT THE INTENSITY OF THE LES...ESPECIALLY OVER THE W DOWNWIND OF
MORE ICE BUILDUP OVER WRN LK SUP. EXPECT LESS BLSN IN THE AFTN GIVEN
TREND FOR DIMINISHING WINDS WITH CLOSER APRCH OF ARCTIC HI PRES.
ALTHOUGH ANOTHER CLIPPER SHRTWV IS FCST TO MOVE INTO NRN MN LATER IN
THE DAY WITH SOME DPVA/DEEP LYR QVECTOR CNVGC IMPACTING UPR
MI...FCST SDNGS HINT THERE WL BE TOO MUCH DRYING IN THE WAKE OF
STRONGER QUEBEC CLIPPER TO ALLOW FOR MUCH MORE THAN BKN CLDS AWAY FM
THE LES AREAS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 446 PM EST SAT JAN 18 2014
A SERIES OF CLIPPERS AND ARCTIC AIR WILL DOMINATE THE LONG TERM
PATTERN AS DEEP TROUGHING ACROSS EASTERN CANADA GENERALLY REMAINS IN
PLACE.
SUNDAY NIGHT THROUGH TUESDAY...A MID-LEVEL LOW IN THE VICINITY OF
JAMES BAY WILL SLOWLY DRIFT EASTWARD ACROSS NORTHERN QUEBEC THROUGH
THE BEGINNING OF THE PERIOD...SENDING A SERIES OF TROUGHS
SOUTHEASTWARD ACROSS UPPER MI. THE FIRST OF THESE WILL CROSS THE
AREA LATE SUNDAY NIGHT IN ASSOCIATION WITH THE CONTINUED ADVECTION
OF ARCTIC AIR ACROSS THE REGION. AN UPTICK IN LES FOR THE N TO NNW
SNOW BELTS IS EXPECTED WITH THE TROUGH PASSAGE AS LAKE EQUILIBRIUM
VALUES SURPASS 9KFT OVER EASTERN LAKE SUPERIOR. HI-RES MODEL
GUIDANCE AND EVEN SOME MEDIUM-RES GUIDANCE IS ALSO STARTING TO
INDICATE A LAKE-INDUCED SFC TROUGH/EASTERLY LAND BREEZE CONV ZONE
NORTH OF GRAND MARAIS. THE LAKE-ICE COVER IS BECOMING MORE
WIDESPREAD OVER FAR EASTERN LAKE SUPERIOR...AND WHITEFISH BAY IS
COMPLETELY FROZEN OVER PER TODAYS SATELLITE IMAGERY. THIS HAS
ALLOWED THE LAND BREEZE CONV ZONE TO SET UP FARTHER WEST TODAY...AND
WOULD EXPECT SIMILAR BEHAVIOR FOR SUNDAY NIGHT...ESPECIALLY WITH
QUITE COLD AIR FLOWING OFF ONTARIO. LITTLE SHOULD CHANGE THROUGH
MONDAY NIGHT AS PERSISTENT NNW FLOW CONTINUES TO BRING ARCTIC AIR
ACROSS THE AREA. SNOWFALL AMOUNTS ARE A LITTLE TRICKY AS THE ARCTIC
AIR TENDS TO MAKE SLR VALUES LOWER. HOWEVER...FROM EXPERIENCE SO FAR
THIS SEASON...THE EXTENDED FETCH FOR THE EASTERN CWA MAY ALLOW FOR
MORE MODERATION OF THE ARCTIC AIR...RESULTING IN A DEEPER FAVORABLE
SNOW GROWTH LAYER. HAVE THUS INCREASED RATIOS A BIT ACROSS THE EAST
WHILE LOWERED THEM ELSEWHERE. ALSO...POROUS ICE COVER DEVELOPING
ACROSS WESTERN LAKE SUPERIOR MAY LIMIT LES TO SOME
DEGREE...ESPECIALLY LOCATIONS DOWNWIND OF ISLE ROYALE. OVERALL...NOT
ANTICIPATING ANY EXTREME SNOWFALL UNLESS A CONVERGENT BAND REMAINS
ANCHORED OVER A GIVEN LOCATION...MOST LIKELY BETWEEN MUNISING AND
GRAND MARAIS...FOR AN EXTENDED PERIOD OF TIME. LOW-END ADVISORY
AMOUNTS ARE POSSIBLE SUNDAY NIGHT THROUGH MONDAY WITH GENERALLY 3 TO
6 INCHES...THOUGH LOCAL AMOUNTS OF 8 INCHES ARE POSSIBLE. THE
NORTHERN EXTENT OF A WEAK SFC RIDGE WILL BACK WINDS ON TUESDAY AND
PUSH LES ACTIVITY OFF SHORE FOR MOST LOCATIONS.
A CONTINUOUS INFLUX OF H8 TEMPS AROUND -25C WILL BE PRESENT MONDAY
THROUGH TUESDAY AND BRING RATHER COLD CONDITIONS ACROSS THE AREA.
HOWEVER...TEMPS SHOULD REMAIN WARMER THAN WAS SEEN EARLIER IN THE
MONTH. ADDITIONALLY...WINDS WILL REMAIN MUCH LIGHTER EXCEPT ALONG
THE WARMER LAKE SHORES. STILL...WITH TEMPS FALLING TO THE TEENS
BELOW ZERO MONDAY NIGHT FOR THE INTERIOR WEST AND CENTRAL...A WIND
CHILL ADVISORY MAY BE NEEDED WITH CHILLS DOWN TO -30F.
WEDNESDAY INTO SATURDAY...YET ANOTHER POTENT CLIPPER WILL PUSH
SOUTHEAST RIGHT OVER THE CWA WEDNESDAY MORNING INTO THE AFTERNOON. A
QUICK ROUND OF MODERATE SNOW IS POSSIBLE FOR MUCH OF THE CWA
WEDNESDAY MORNING WITH IMPRESSIVE Q-VECTOR CONVERGENCE AND UPPER PV
ANOMALY. THE GFS HAS BEEN THE OUTLIER WITH THIS SYSTEM...SO HAVE
TRENDED WITH THE ECMWF AND GEM. BEHIND THE SYSTEM...INCREASING N TO
NE GRADIENT FLOW BETWEEN A LAGGING 1020 MB LAKE-INDUCED TROUGH AND
IMPINGING 1044 MB HIGH WILL BRING A POSSIBLY INTENSE BOUT OF LAKE
ENHANCED SNOW TO NORTH-CENTRAL UPPER MI. HAVE BUMPED UP POPS
CONSIDERABLY...AND LATER SHIFTS WILL NEED TO MONITOR MODEL TRENDS AS
HEADLINES WILL BE POSSIBLE WEDNESDAY AFTERNOON AND EVENING ALONG
LAKE SUPERIOR.
TEMPS CONTINUE TO REMAIN WELL BELOW NORMAL INTO THURSDAY AFTER
ANOTHER SHOT OF -25C H8 TEMPS WEDNESDAY AFTERNOON. DID NOT DEVOTE
MUCH TIME TO THE FORECAST BEYOND WEDNESDAY GIVEN MODEL DISAGREEMENT
AT THIS TIME...THOUGH WEIGHTED THE FORECAST TOWARD THE MORE
CONSISTENT ECMWF. INDICATIONS ARE THAT ANOTHER POTENT TROUGH AND
ACTIVE FEW DAYS OF WX WILL AFFECT THE AREA FRIDAY INTO SATURDAY
MORNING...WITH PERSISTENT LES FOR WNW SNOW BELTS THROUGH THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1151 PM EST SAT JAN 18 2014
DEEPENING SFC LOW PRES MOVING ACROSS NRN ONTARIO WILL SEND
ASSOCIATED COLD FRONT S INTO THE UPPER LAKES OVERNIGHT AND THIS
MORNING. UNDER TIGHTENING PRES GRADIENT...W TO SW WINDS WILL BE
GUSTY OVERNIGHT AHEAD OF FRONT. COMBINATION OF FALLING AND BLSN
WHIPPED UP BY THE GUSTY WINDS WILL LEAD TO VIS VARYING BTWN IFR AND
MVFR AT KIWD AND LIKELY A PREVAILING LIFR VIS AT THE MORE EXPOSED
KCMX LOCATION. DOWNSLOPE NATURE OF THE EXPECTED WSW FLOW WILL LIKELY
MAINTAIN VFR WX AT KSAW EVEN AFTER -SN BEGINS. STRONG SUBSIDENCE AND
DIMINISHING WINDS IN THE WAKE OF COLD FROPA THIS MORNING SHOULD
LIMIT THE INTENSITY OF LAKE EFFECT SNOW/BLSN...BUT IFR VIS IS LIKELY
TO PERSIST THRU THE MORNING AT KCMX BEFORE IMPROVEMENT TO MVFR IN
THE AFTN. WSHFT TO A MORE UPSLOPE NNW DIRECTION WILL LEAD TO
DEVELOPMENT OF MVFR CONDITIONS AT KSAW. ALL TERMINALS SHOULD
GENERALLY BE MVFR THIS AFTN/EVENING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 446 PM EST SAT JAN 18 2014
RELATIVELY LIGHT WINDS EARLY THIS EVENING WILL GIVE WAY TO A WSW
GALE OVER MUCH OF CENTRAL AND EASTERN LAKE SUPERIOR OVERNIGHT AS THE
PRES GRADIENT TIGHTENS OVER THE UPPER LAKES S OF DEEPENING LO PRES
CROSSING ONTARIO. THE GALES WILL VEER TO THE NW ON SUN MORNING
FOLLOWING A COLD FRONTAL PASSAGE...BUT THE WINDS WILL TEND TO
DIMINISH TO 25-30 KTS DURING THE AFTERNOON WITH ARRIVAL OF WEAKER
PRES GRADIENT AHEAD OF APPROACHING HI PRES IN THE NORTHERN PLAINS.
DESPITE THE WEAKENING WINDS...ARRIVAL OF VERY COLD ARCTIC AIRMASS
WILL RESULT IN SOME HEAVY FREEZING SPRAY IN THE AFTERNOON OVER ABOUT
THE E HALF...SO STARTED THE HEAVY FREEZING SPRAY WARNING FOR THIS
AREA AT 18Z SUN. GOING GALE HEADLINE LOOKS TO BE IN GOOD SHAPE.
PERSISTENT NW FLOW OF 20 TO 30 KNOTS WILL CONTINUE THROUGH MONDAY
NIGHT BEFORE WINDS BACK AND WEAKEN IN RESPONSE TO THE NORTHERN
EXTENT OF A SFC RIDGE TUESDAY INTO TUESDAY NIGHT. A POTENT SYSTEM
TRACKING SE OVER UPPER MI WEDNESDAY MAY BRING N TO NE GALES ACROSS
MUCH OF THE LAKE WEDNESDAY AFTERNOON AND NIGHT. ANOTHER WEAK RIDGE
WILL DIMINISH AND BACK WINDS TO THE SW ON THURSDAY. THEN...SW GALES
TO 35 KNOTS WILL BE POSSIBLE THURSDAY NIGHT INTO FRIDAY AHEAD OF
ANOTHER STRONG TROUGH ACROSS SOUTH CENTRAL CANADA. 20 TO 30 KNOTS
WILL CONTINUE THROUGH SATURDAY WHILE VEERING TO THE NW.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 1 PM SUNDAY TO 7 AM EST
TUESDAY FOR LSZ251-267.
GALE WARNING UNTIL 4 PM EST SUNDAY FOR LSZ249>251-266-267.
HEAVY FREEZING SPRAY WARNING FROM 1 PM SUNDAY TO 7 PM EST
TUESDAY FOR LSZ249-250-266.
HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 1 PM EST
TUESDAY FOR LSZ244-245-248-264-265.
GALE WARNING UNTIL 7 AM EST SUNDAY FOR LSZ242>245-263>265.
HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 7 AM EST
TUESDAY FOR LSZ243-263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KLUBER
AVIATION...ROLFSON
MARINE...KC/KLUBER
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1101 PM CST SAT JAN 18 2014
.UPDATE...FOR 06Z AVIATION DISCUSSION BELOW
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 348 PM CST SAT JAN 18 2014
WEATHER HAS BEEN QUIETING DOWN QUICKLY IN THE WAKE OF THIS MORNINGS
STRONG CLIPPER. STRONG SUBSIDENCE IN THE WAKE OF THE CLIPPER HAS
HELPED CLEAR SKIES OUT...SAVE FOR A LINGERING ZONE OF FGEN AROUND H7
THAT HAS KEPT AN AREA OF CLOUDS WITH A FEW FLURRIES GOING FROM THE
TWIN CITIES BACK TOWARD EAU...THOUGH EVEN THESE CLOUDS SHOULD SLOWLY
FADE AWAY THIS AFTERNOON.
TONIGHT...WINDS WILL QUICKLY TURN TOWARD THE SW AS A MILD PACIFIC
AIRMASS QUICKLY MOVES INTO THE AREA. WAA OUT AHEAD OF THE WARM NOSE
WILL LEAD TO A BAND OF MAINLY MID LEVEL CLOUDS WORKING BACK ACROSS
THE AREA. HOWEVER...290-295K SFCS OFF THE NAM SHOWING ENOUGH
MOISTURE MAY BE PRESENT FOR ISENTROPIC LIFT IN THE FAR NE CWA TO
GENERATE SOME -SN AS THE WARMER AIRMASS MOVES IN. THIS IS SUPPORTED
BY REFLECTIVITY FORECASTS FROM THE HRRR AND OTHER HI-RES MODELS...SO
INTRODUCED SOME CHANCE POPS FOR THAT...THOUGH ONLY ONE OR TWO TENTHS
OF AN INCH OF SNOW WOULD BE LIKELY IF ANYTHING DOES FALL. THIS WAA
TONIGHT WILL RESULT IN ANOTHER NIGHT OF NON-DIURNAL TEMP
TRENDS...WITH TEMPS LIKELY ALREADY ABOVE 30 OFF THE BUFFALO RIDGE BY
SUNRISE SUNDAY...WITH MOST OF THE MN CWA INTO THE LOW/MID 20S BY THE
START OF THE DAY SUNDAY. THE WARM START MEANS THE MILD DAY STILL
LOOKS TO BE IN PLACE. FOLLOWED MORE THE GEM/ECMWF FOR HIGHS SUNDAY
WITH MOST OF THE AREA GETTING INTO THE LOW/MID 30S. IF YOU WOULD
LIKE TO AVOID THOUGHTS OF NEEDING A VACATION TO A WARMER CLIMATE...I
SUGGEST YOU STOP READING NOW...AS THESE HIGHS SUNDAY WILL NOT BE A
LASTING TREND.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 348 PM CST SAT JAN 18 2014
THE ROLLER COASTER RIDE OF TEMPERATURE TRENDS WILL CONTINUE
THROUGHOUT THE LONG TERM. AN ARCTIC FRONT WILL SAG SOUTH SUNDAY
NIGHT INTO CENTRAL MN AND WI. STEEP LAPSE RATES UP TO ABOUT 3KFT
IN STRONG CAA REGIME AND AN ISOTHERMAL MOIST TEMPERATURE PROFILE
WITHIN THE DGZ BETWEEN 3KFT TO 10KFT SHOULD PROMOTE OCCASIONAL
LIGHT SNOW DEVELOPMENT BEHIND THE FRONT UNTIL DRIER AIR WORKS IN
MONDAY AFTERNOON. BOOSTED POPS INTO THE CATEGORICAL RANGE...BUT
THIS LOOKS LIKE A HIGH CHANCE/LOW PRECIP EVENT WITH SNOWFALL
AMOUNTS REMAINING GENERALLY A HALF INCH OR LESS. THE BEST CHANCE
OF RECEIVING UP TO AN INCH WILL BE ACROSS WESTERN AND SOUTHERN MN
WHERE A VORTICITY MAX SLIDES SOUTHEAST IN ADVANCE OF THE BUILDING
SURFACE RIDGE MONDAY AFTERNOON. THIS WILL ENHANCE THE LIFT ENOUGH
TO GET A BIT MORE ROBUST SNOWFALL.
THE HIGH BUILDS INTO WESTERN MN MONDAY NIGHT. CLEARING SKIES AND
FRESH SNOWFALL WILL EASILY ALLOW FOR A STOUT INVERSION TO SET UP
WHICH SHOULD ALSO DECOUPLE THE WIND. IF THE WIND FULLY
DECOUPLES...TEMPERATURES WILL BE VERY COLD WITH WIDESPREAD 20S
BELOW ACROSS MN /EXCEPT FOR THE TWIN CITIES METRO/ AND TEENS BELOW
ACROSS WI. SOME SPOTS IN CENTRAL MN MAY DROP TO 30 BELOW AGAIN.
FORECASTING TEMPERATURES IN SUCH A SITUATION IS INHERENTLY
DIFFICULT AS LOCATIONS CAN VARY GREATLY WITH ENHANCED LOCAL
INFLUENCES. THEREFORE...CONFIDENCE IS NOT PARTICULARLY HIGH AND IT
IS IMPOSSIBLE TO CONVEY THESE HIGHLY VARIED LOCAL INFLUENCES WITH
MUCH PRECISION IN THE GRIDS. UNLIKE THE LAST COLD OUTBREAK...THE
COLDER MOS NUMBERS MAY NOT BE AS FAR OFF FROM REALITY IN THE
DECOUPLED ENVIRONMENT. TOOK A COMPROMISE OF THE MOS NUMBERS AND
THE BIAS CORRECTED MOS NUMBERS FOR TEMPS HOPING SPLITTING THE
DIFFERENCE WILL SUFFICE.
BY TUESDAY NIGHT...A WEAK DISTURBANCE WILL DROP SOUTHEAST INTO THE
GREAT LAKES. WITH IT WILL COME A NOSE OF WARMER AIR IN OVERNIGHT
AND A CHANCE OF SNOW ACROSS MUCH OF THE AREA.
THE NEXT ARCTIC FRONT WILL ARRIVE WEDNESDAY AND ANOTHER POLAR HIGH
WILL BUILD INTO THE DAKOTAS AND MINNESOTA WEDNESDAY NIGHT. IT WILL
BE A NEARLY IDENTICAL SET UP TO MONDAY NIGHT AND THE LOW TEMP GRID
IS QUITE SIMILAR AS WELL.
SOME UNCERTAINTY HAS BEEN INTRODUCED BY THE MIDDLE OF NEXT WEEK
WITH THE GFS SHOWING A MUCH MILDER SOLUTION COMPARED TO PREVIOUS
DAYS RUNS. IT SHOWS THE TROUGH BEING CONFINED TO NEW ENGLAND AND
AN EXPANSIVE ZONAL FLOW/WEAK RIDGING ACROSS THE REST OF THE CONUS.
PREFER THE MORE STABLE ECMWF SHOWING A CONTINUATION OF A SERIES OF
POLAR FRONTS THROUGH DAY 10. NOT SEEING MUCH TO INDICATE THE
CURRENT PATTERN WILL CHANGE AND GIVEN HOW LONG IT HAS PERSISTED
THIS WINTER...IT WILL TAKE QUITE A BIT MORE CONVINCING BEFORE A
CHANGE IN DIRECTION IS NECESSARY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1101 PM CST SAT JAN 18 2014
MVFR CIGS WILL SKIRT THE NORTHERN/EASTERN TAF SITES OVERNIGHT
...PRIMARILY AFFECTING KSTC AND POSSIBLY KRNH/KEAU.
OTHERWISE...MAINLY MID/HIGH CLOUDS ARE EXPECTED UNTIL SUNDAY
AFTERNOON...WHEN MVFR CLOUDS OVER NORTHERN MN WILL SINK INTO
CENTRAL MN/WI. SNOW CHANCES WILL INCREASE AFTER 03Z MONDAY AS THE
LOWER CLOUDS BUILD IN. SOUTHWEST WINDS WILL VEER BACK TO THE
NORTHWEST BETWEEN 15Z-18Z SUNDAY.
KMSP...
SCT MVFR LEVEL CLOUDS COULD SKIRT THE NORTHERN EDGES OF KMSP
TONIGHT. OTHERWISE...THE HIGHER CHANCE OF MVFR CIGS WILL ARRIVE
AFTER 00Z MON...WITH LIGHT SNOW APPEARING POSSIBLE AFTER 05Z MON.
WEST/SOUTHWEST WINDS TONIGHT VEER TO THE NORTHWEST BY 15Z SUNDAY.
SPEEDS AOB 10 KTS THRU PD.
/OUTLOOK FOR KMSP/
MON...CHANCE MVFR/SN THRU MORNING. WINDS N 10KTS.
TUE...VFR. CHANCE MVFR CIGS/-SN TUE NIGHT. WINDS W-SW 5KTS.
WED...VFR. WINDS NW 10G20KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...BORGHOFF
AVIATION...LS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
342 AM EST SUN JAN 19 2014
.SYNOPSIS...
A DISTURBANCE IN THE JET STREAM WINDS ALOFT AND AN ARCTIC COLD
FRONT WILL PRODUCE PERIODS OF SNOW SHOWERS ACROSS THE NORTH
COUNTRY TODAY AND TONIGHT. OVERALL...SNOW ACCUMULATIONS WILL BE
LIGHT WITH 1 TO 3 INCHES IN GENERAL EXPECTED. BEHIND THE
FRONT...A RETURN OF MUCH COLDER AND DRIER CONDITIONS IS EXPECTED
FOR THE UPCOMING WEEK...WITH HIGHS ONLY IN THE SINGLE DIGITS
ABOVE ZERO AND LOWS IN THE SINGLE DIGITS TO TEENS BELOW FOR
MONDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 340 AM EST SUNDAY...VERY LITTLE OVERALL CHANGE FROM
PREVIOUS FORECAST THINKING FOR TODAY AS THE ATMOSPHERE IS
BEHAVING MUCH LIKE WE EXPECTED. LATEST GUIDANCE CONTINUES TO SLOW
DOWN THE APPROACH OF AN ARCTIC FRONT WHICH NOW LOOKS TO AFFECT
THE NORTH COUNTRY TOWARD THIS EVENING AND TONIGHT...SO FOR TODAY
WE`LL BE DEALING WITH A POTENT SHORTWAVE TROUGH CURRENTLY OVER
THE OHIO RIVER VALLEY WHICH WILL SHIFT EASTWARD THROUGH THE MID-
ATLANTIC STATES. LATEST WV IMAGERY CONTINUES TO SUPPORT THE IDEA
THAT THE BEST PVA SLIDES TO OUR SOUTH TODAY...BUT 13KM RAP
CONTINUES TO SHOW A PIECE OF ENERGY BREAKING OFF AND TRACKING
NORTHEAST THROUGH THE CWA THIS MORNING. WITH THE EXCEPTIONAL
PERFORMANCE OF THE RAP OVER THE LAST FEW DAYS IT`S HARD TO IGNORE
IT...AND OVERALL IT MAKES SENSE BASED ON THE UPPER FLOW TRENDING
SOUTHWESTERLY. THAT SAID...WE`LL SEE PERIODS OF SNOW SHOWERS THIS
MORNING THROUGH ABOUT MID-DAY...WITH A BREAK IN THE ACTION THIS
AFTERNOON AS THE SHORTWAVE ENERGY SHIFTS NORTHEAST OF THE REGION
AND WE AWAKE ANOTHER ROUND OF SNOW SHOWERS ASSOCIATED WITH THE
ARCTIC FRONT. OVERALL QPF WILL BE VERY LIGHT WITH JUST A FEW
HUNDREDTHS OF LIQUID EXPECTED...AMOUNTING TO JUST A DUSTING TO
MAYBE 2 INCHES THROUGH THE DAY. TEMPS WILL BE THE LAST ABOVE
NORMALS WE`LL SEE FOR AWHILE AND GENERALLY IN THE 20S TO A FEW
LOW 30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
AS OF 340 AM EST SUNDAY...FOR TONIGHT INTO MONDAY FOCUS TURNS
TOWARDS AN ARCTIC BOUNDARY WHICH WILL SWING NORTHWEST TO
SOUTHEAST THROUGH THE CWA. AS MENTIONED ABOVE...LATEST GUIDANCE
CONTINUES TO SLOW THE PROGRESSION OF SAID FEATURE WITH SOME
RESIDUAL LAKE ENHANCED SNOW SHOWERS NOW POSSIBLY LINGERING
THROUGH MID-DAY MONDAY ACROSS CENTRAL AND SOUTHERN AREAS.
OVERALL...FRONT SHOULD MOVE INTO NORTHWESTERN PORTIONS OF THE
REGION LATE THIS EVENING WITH LOCAL WRF`S AND RAP CONTINUING TO
SHOW FAVORABLE CONDITIONS FOR SNOW SQUALLS. THINKING ANOTHER
DUSTING TO 2 INCHES WILL BE POSSIBLE TONIGHT...WITH MUCH OF THAT
LIKELY OCCURRING IN A VERY SHORT PERIOD OF TIME. COME MONDAY
MORNING FRONT WILL BE SOMEWHERE ACROSS CENTRAL AND SOUTHERN
VERMONT WITH SOME LINGERING LAKE ENHANCED SHOWERS SHOWERS AROUND
ESPECIALLY ACROSS THE HIGHER TERRAIN...BUT AS DRIER AIR MOVES IN
UNDER STRONG CAA ON NORTHWEST FLOW SNOW SHOULD TAPER OFF BY THE
AFTERNOON HOURS. DAYTIME HIGHS IN THE TEENS WILL LIKELY BE
REACHED DURING THE MORNING HOURS...SLOWLY FALLING THROUGH THE DAY
WITH THE EXCEPTION BEING THE FAR SOUTHEAST CORNER OF VT WHERE
HIGHS WILL BE IN THE MID 20S AHEAD OF THE FRONT.
FOR MONDAY NIGHT AND TUESDAY SURFACE HIGH PRESSURE BUILDS INTO
THE REGION WITH CLEARING SKIES AND BONE CHILLING TEMPERATURES
EXPECTED. MONDAY NIGHT LOWS WILL FALL INTO THE SINGLE DIGIT TO
TEENS BELOW ZERO...AND WITH MODERATE GRADIENT FLOW REMAINING
BETWEEN THE BUILDING HIGH AND DEPARTING LOW WE`LL LIKELY BE
LOOKING AT SOME WIND CHILL ADVISORIES FOR PORTIONS OF NORTHERN
NEW YORK AND NORTHEAST VERMONT. WINDS WILL SLACKEN OFF FOR TUESDAY
WITH PARTLY SUNNY SKIES AND HIGHS ONLY IN THE THE SINGLE DIGITS
BELOW TO 10 ABOVE.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 212 AM EST SUNDAY...QUIET...COLD AND MAINLY DRY PATTERN WILL
BECOME LOCKED IN ACROSS THE EASTERN HALF OF THE U.S. DURING THE
MID TO LATE WEEK TIME FRAME AND LIKELY BEYOND AS ARCTIC AIR HAS A
DIRECT PATHWAY INTO OUR REGION. THIS IS A VERY STABLE
PATTERN...AND UNTIL MORE ORGANIZED ENERGY CAN CRASH EASTWARD
THROUGH THE HIGH-AMPLITUDE WESTERN CONUS RIDGE...THE CURRENT HIGH
AMPLITUDE PATTERN SHOULD MORE OR LESS HOLD IN PLACE FOR THE NEXT
10 DAYS. IN TERMS OF SENSIBLE WEATHER...TEMPERATURES WILL REMAIN
WELL BELOW NORMAL WEDNESDAY INTO FRIDAY THOUGH WITH SOME SLIGHT
AIRMASS MODERATION BY ABOUT 5 DEGREES EACH DAY. OVERNIGHT LOWS
CONSISTENTLY BELOW ZERO WITH COLDEST NIGHT OCCURRING TUESDAY NIGHT
WHEN WIDESPREAD 10 TO 20 BELOW READINGS LIKELY. A WEAK CLIPPER LOW
PASSING SOUTH OF THE AREA MAY SPREAD SOME CLOUDINESS AND PERHAPS A
BRIEF PERIOD OF FLURRIES/VERY LIGHT SNOW TO OUR SOUTHERN COUNTIES
ON THURSDAY...OTHERWISE MAINLY DRY WEATHER IS EXPECTED THROUGH
FRIDAY.
BY FRIDAY NIGHT SOUTHERLY FLOW RETURNS AS SFC RIDGE DEPARTS EAST
ALLOWING TEMPERATURES TO CLIMB SLOWLY...REACHING NEAR MID-WINTER
SEASONAL NORMS FOR ONE BRIEF DAY ON SATURDAY. ADDITIONAL NORTHERN
STREAM ENERGY ACCOMPANIED BY YET ANOTHER IMPRESSIVE ARCTIC BOUNDARY
TO THEN SWEEP INTO THE REGION BY LATER SATURDAY/SATURDAY NIGHT WHERE
I`LL MAINTAIN SOLID CHC POPS FOR SLIGHTLY BETTER COVERAGE OF SHSN.
BEHIND THIS FRONT...ALL INDICATIONS SUGGEST WE`LL ONCE AGAIN ENTER
THE DEEP FREEZE FOR AT LEAST A FEW MORE DAYS FROM NEXT SUNDAY ONWARD
AS ARCTIC HIGH PRESSURE REASSERTS ITSELF ACROSS THE NORTHEAST. WISH
I COULD PAINT A MORE INTERESTING AND/OR COMFORTABLE PATTERN...BUT
ALL INDICATIONS SUGGEST VERY COLD AND DRY THROUGH THE END OF THE
MONTH.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
THROUGH 06Z MONDAY...VRB CONDS OF VFR/MVFR/OCCNL IFR EXPECTED OVER
THE NEXT 24 HOURS AS SCT LIGHT SNOWS/FLURRIES AFFECT THE REGION
THROUGH 18Z...THEN MORE DISCRETE BANDS/AREAS OF SHSN AND POSSIBLE
SQUALLS 18-06Z WITH APPROACH/PASSAGE OF ARCTIC COLD FRONT. BEST
SHOT OF IFR THROUGH 18Z TO OCCUR AT KMPV/KSLK AND POSSIBLY KMSS.
WITH PASSAGE OF ARCTIC FRONT AND BANDED HEAVIER SHSN/SQUALLS...IFR
POSSIBLE AT ALL TERMINALS BUT GIVEN THE FACT THAT THIS WILL
GENERALLY OCCUR IN THE 00-06Z TIME FRAME ON MONDAY AND FOR ONLY A
BRIEF PERIOD OF TIME...KEPT MORE GENERIC SHSN WORDING IN TERMINAL
FORECASTS AT THIS POINT UNTIL HIGHER CONFIDENCE OF TIMING OCCURS
LATER TODAY. WINDS GENERALLY LIGHT SOUTH TO SOUTHWESTERLY AND
MAINLY LESS THAN 10 KTS...EVEN NEARLY CALM AT SELECTED TERMINALS
THROUGH 12Z. THEREAFTER SOUTH/SOUTHWESTERLY FLOW INCREASES AFTER
12Z AND TRENDS QUITE GUSTY INTO THE AFTERNOON/EVENING HOURS AHEAD
OF THE FRONT...ESP AT KBTV/KSLK/KMSS.
OUTLOOK 06Z MONDAY THROUGH THURSDAY...
06Z THROUGH 12Z MONDAY...VFR WITH SCT MVFR/IFR IN SHSN AS ARCTIC
FRONT PUSHES THROUGH THE AREA. BEST SHSN COVERAGE 18-06Z.
12Z MONDAY ONWARD...MAINLY VFR WITH HIGH PRESSURE.
&&
.EQUIPMENT...
AS OF 340 AM EST SUNDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM BUT IT WILL
LIKELY BE OUT OF SERVICE THROUGH AT LEAST TUESDAY JANUARY 21.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...JMG/LOCONTO
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1133 PM CST SAT JAN 18 2014
.AVIATION...
THE KCDS ASOS HAS BEEN REPORTING A CLOUD LAYER THIS EVENING NEAR
OR JUST ABOVE MVFR LEVELS WHICH HAS BEEN SOMEWHAT DIFFICULT TO
RESOLVE METEOROLOGICALLY. ONLY THE RAP SHORT TERM SOLUTION IS
SHOWING MOISTURE NEAR THIS LEVEL...THOUGH MAINLY JUST TO THE EAST
IN WESTERN OKLAHOMA NEAR A SLOPED SHALLOW FRONTOGENETICALLY
FORCED REGION. THE DIFFERENCE CHANNEL SATELLITE IMAGES HAVE NOT
CLEARLY DEPICTED ANY CLOUD FEATURE IN THE KCDS AREA...THOUGH THERE
APPEAR TO BE VERY SUBTLE CONTRAST DIFFERENCES SUGGESTING PERHAPS
SMALL ISOLATED CLOUD FEATURES ARE POSSIBLE. AND A CALL TO THE AREA
DID NOT REVEAL ANY NOTABLE CLOUDS. STILL...BECAUSE OF THE
PERSISTENT REPORTING IN ASOS WE HAVE ADDED A SCATTERED 3000 FOOT
CLOUD LAYER AT KCDS FOR ANOTHER HOUR AND A HALF...FOR THE
POSSIBILITY THE REPORT IS CORRECT. OTHERWISE VFR CONDITIONS ARE
EXPECTED FOR THE EARLY PART OF BOTH THE KCDS AND KLBB TAF
FORECASTS WITH A WEAK SURFACE RIDGE OVERHEAD WITH LIGHT WIND FLOW.
SURFACE PRESSURE FALLS ARE STILL ANTICIPATED BY MID TO LATE SUNDAY
MORNING THAT SHOULD INITIATE BREEZY TO LOW-END WINDY CONDITIONS
FROM THE SOUTHWEST. SPEEDS APPEAR JUST STRONG ENOUGH FOR A LIGHT
DUST VISIBILITY RESTRICTION AT KLBB...THOUGH AS LOW AS 6 STATUTE
MILES SEEMS REMOTE AT THE PRESENT TIME. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 515 PM CST SAT JAN 18 2014/
AVIATION...
VFR CONTINUING IN VERY DRY NORTHWEST FLOW ALOFT. THE LATEST WEAK
SURFACE HIGH PRESSURE RIDGE WILL SLIDE SOUTHEASTWARD ACROSS THE
AREA OVERNIGHT WITH LIGHT AND VARIABLE WINDS...FOLLOWED BY SURFACE
PRESSURE FALLS SUNDAY MORNING AND THE ONSET OF GUSTY SOUTHWEST
BREEZES AGAIN BY LATE SUNDAY MORNING. WINDS MAY BECOME STRONG
ENOUGH FOR A LIGHT VISIBILITY RESTRICTION MAINLY AT KLBB...WE WILL
TAKE A LOOK AGAIN FOLLOWING RELEASE OF THE 00Z GUIDANCE THIS
EVENING. RMCQUEEN
PREV DISCUSSION... /ISSUED 233 PM CST SAT JAN 18 2014/
SHORT TERM...
BREEZY NORTHERLY WINDS HAVE OVERSPREAD MOST OF THE AREA BEHIND A
WIND SHIFT THAT MOVED THROUGH THIS MORNING. NO COOLING WAS
ASSOCIATED WITH THE BOUNDARY...WITH TEMPERATURES ACTUALLY RUNNING
ABOUT 10-15 DEGREES ABOVE YESTERDAY AT THIS SAME TIME. THE BREEZY
AND WARM WINDS...COUPLED WITH DRY CONDITIONS...WERE ALSO ACTING TO
ELEVATE THE FIRE DANGER. THE WINDS WILL RAPIDLY DIMINISH THIS
EVENING AS DEEPER MIXING ENDS AND THE BOUNDARY LAYER DECOUPLES. A
FEW HIGH CLOUDS MAY BRIEFLY SKIRT THE FAR NORTHEASTERLY ZONES...BUT
OTHERWISE CLEAR SKIES AND LIGHT WINDS WILL SUPPORT ANOTHER
SEASONABLY CHILLY NIGHT TONIGHT. LOWS WILL BOTTOM OUT IN THE 20S FOR
MOST LOCALES...WITH A FEW TEENS POSSIBLE ACROSS THE NORTH-CENTRAL
AND NORTHWEST ZONES AND A FEW 30S POSSIBLE OUT EAST.
SUNDAY WILL BRING A RETURN TO ABOVE AVERAGE TEMPERATURES...SPURRED
ON BY DEVELOPING GUSTY DOWNSLOPE SOUTHWESTERLY WINDS WITHIN THE DRY
AIR MASS THAT WILL CONTINUE TO ENVELOP THE REGION. THE WINDS WILL
PEAK ABOVE TODAY/S LEVELS AS THE LOCAL PRESSURE GRADIENT STRENGTHENS
AHEAD OF A SUBTLE SHORTWAVE TROUGH APPROACHING WITHIN THE
NORTHWESTERLY FLOW ALOFT. THE LATEST NWP SHOWS A 850 MB LOW LEVEL
JET OF 25 TO 35 KNOTS DEVELOPING OVER THE AREA BY MIDDAY. ALTHOUGH
MIXING IS NOT PROGGED TO BE VERY DEEP...WE SHOULD STILL TAP THIS
JET...SUPPORTING PLENTY OF GUSTINESS THROUGH THE AFTERNOON HOURS.
ATTM...IT APPEARS THE NORTHWESTERN AND NORTH-CENTRAL ZONES WILL BE
IN THE MOST FAVORED LOCATION FOR THE STRONGEST WINDS...WITH
SUSTAINED WINDS OF 25-30 MPH A GOOD BET THERE. WOULD NOT EVEN BE
SURPRISED TO SEE A FEW SPOTS IN THIS AREA THREATEN LOW-END ADVISORY
LEVELS /31-39 MPH SUSTAINED/. ELSEWHERE...FURTHER SOUTH ACROSS THE
SOUTH AND ROLLING PLAINS...SUSTAINED WINDS WILL LIKELY PEAK AROUND
20-25 MPH SUNDAY AFTERNOON. THIS GUSTY WINDS COULD EVEN LOFT A BIT
OF BLOWING DUST...AND WE HAVE MAINTAINED THE PATCHY BLOWING DUST
MENTION ACROSS MUCH OF THE CAPROCK INTO THE WESTERN ROLLING PLAINS.
DID ALSO DECIDE TO INCLUDE AREAS OF BLOWING DUST ACROSS THE
NORTHWESTERN ZONES WHERE THE WINDS ARE EXPECTED TO BE THE STRONGEST.
ON THE POSITIVE SIDE...TEMPERATURES WILL BE PLEASANT...TOPPING OUT
IN THE UPPER 60S AND LOWER 70S. UNFORTUNATELY...THE WARM...DRY AND
WINDY CONDITIONS WILL INCREASE THE FIRE DANGER INTO THE ELEVATED TO
CRITICAL CATEGORY THOUGH. SEE THE BELOW FIRE WEATHER SECTION FOR
DETAILS.
LONG TERM...
NO SIG CHANGES THIS AFTN AS MODELS CONTINUE TO HOLD A STAGNANT
UPPER PATTERN ACROSS NORTH AMERICA. ONLY A SERIES OF UPPER LEVEL
SHORT WAVE TROUGHS MOVING THROUGH THE NWLY FLOW OVER THE PLAINS
STATES WILL BRING SUBTLE DIFFERENCES TO THE WEATHER THROUGH THE
WEEK. SPECIFICALLY...WEAK COLD FRONT PASSAGES ABOUT EVERY TWO TO
THREE DAYS WILL HELP KEEP TEMPS JUST EITHER SIDE OF SEASONAL NORMS
MOST DAYS THROUGH THE PERIOD. MODELS HAVING DIFFICULTY WITH A
STRONGER TROUGH THAT IS PROGGED TO CREST THE WEST COAST UPPER
RIDGE LATE IN THE WEEK WITH VARIOUS RUNS SHOWING DIFFERENCES IN
STRENGTH AND POSITIONING...BUT NONE ATTM PROGGING MUCH IN THE WAY
OF CHANGE FOR THE FCST AREA HEADING INTO NEXT WEEKEND.
FIRE WEATHER...
BREEZY NORTHERLY WINDS OF 15 TO 25 MPH HAVE COMBINED WITH
TEMPERATURES IN THE 60S AND RH VALUES IN THE MIDDLE TEENS TO ELEVATE
THE FIRE DANGER THIS AFTERNOON. GIVEN THIS...WE HAVE ISSUED A FIRE
DANGER STATEMENT VALID UNTIL 00Z FOR ALL BUT OUR SOUTHEAST
ZONES...WHERE THE WINDS SHOULD REMAIN LIGHTER. WINDS WILL QUICKLY
DIMINISH AROUND SUNSET...ENDING THE ELEVATED FIRE WEATHER FOR THE
DAY.
EVEN STRONGER SOUTHWESTERLY WINDS ARE ANTICIPATED ON SUNDAY...AS A
WEAK DISTURBANCE APPROACHES FROM THE NORTHWEST. SUSTAINED WINDS OF
20-30 MPH WILL BECOME COMMON DURING THE AFTERNOON HOURS...WITH
TEMPERATURES PEAKING IN THE 60S AND LOWER 70S AND HUMIDITIES FALLING
WELL INTO THE TEENS. THE COMBINATION OF FACTORS WILL RESULT IN
WIDESPREAD ELEVATED TO CRITICAL FIRE WEATHER SUNDAY AFTERNOON...AND
A FIRE WEATHER WATCH HAS BEEN ISSUED VALID FROM 11 AM TO 6 PM ON
SUNDAY. AT THIS TIME...IT APPEARS THE STRONGEST WINDS WILL BE ACROSS
THE SOUTHERN TEXAS PANHANDLE INTO THE NORTHERN SOUTH PLAINS...WHILE
THE SOUTHERN SOUTH AND ROLLING PLAINS WILL EXPERIENCE MORE MARGINAL
WINDS AROUND 15 TO 25 MPH AT THE 20 FOOT LEVEL. HUMIDITIES WILL NOT
BE EXTREME BY WEST TEXAS STANDARDS...BUT WILL LIKELY DIP TO 10-15
PERCENT BY MID TO LATE AFTERNOON. CONDITIONS WILL GRADUALLY IMPROVE
SUNDAY EVENING AS WINDS AND TEMPERATURES DECREASE AND HUMIDITIES
RISE.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 22 68 27 56 23 / 0 0 0 0 0
TULIA 23 68 26 57 23 / 0 0 0 0 0
PLAINVIEW 21 68 26 59 22 / 0 0 0 0 0
LEVELLAND 23 68 27 61 23 / 0 0 0 0 0
LUBBOCK 24 68 28 62 23 / 0 0 0 0 0
DENVER CITY 25 68 30 63 24 / 0 0 0 0 0
BROWNFIELD 24 68 28 63 23 / 0 0 0 0 0
CHILDRESS 29 72 30 60 26 / 0 0 0 0 0
SPUR 28 71 29 62 26 / 0 0 0 0 0
ASPERMONT 25 73 31 65 26 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM 11 AM CST SUNDAY THROUGH SUNDAY
AFTERNOON FOR THE FOLLOWING ZONES: TXZ021>044.
&&
$$
99/99/05
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
410 AM MST SUN JAN 19 2014
.SHORT TERM...BROAD UPPER RIDGING HAS NUDGED INLAND A BIT ALONG
THE WEST COAST WITH RESULTANT DECREASING NORTHWEST FLOW ALOFT
OVER COLORADO. AIRMASS IS QUITE DRY AND STABLE BUT THERE IS A WEAK
RIPPLE WHICH WILL RESULT IN JUST SOME HIGH CLOUDS AT TIMES LATER
THIS AM AND AFTERNOON. AIRMASS WILL CONTINUE TO WARM TODAY AS
700MB TEMPS RISE TO AROUND +3C WHICH WILL ALLOW TEMPERATURES TO
CLIMB INTO THE LOWER AND MID 60S OVER THE PLAINS. RECORD HIGH IN
DENVER IS 68 TODAY BUT DON`T THINK WILL GET QUITE THAT WARM. THERE
WILL BE SOME GUSTY WINDS OVER THE EAST SLOPES AND BASE OF THE
FOOTHILLS THIS MORNING WITH MODEST STABLE INVERSION AT 700MB THIS
AM. ALREADY SEEING SOME GUSTS IN THE 30-40KT RANGE IN THE
NORTHERN FRONT RANGE FOOTHILLS. LATEST RAP CROSS SECTIONS SHOWING
WINDS DECREASING THIS AFTERNOON BUT STILL A DECENT SURFACE
GRADIENT IN PLACE THROUGH MUCH OF THE DAY. AS LOW LEVELS MIX OUT
COULD STILL SEE GUSTY WINDS OVER THE NORTHEAST PLAINS TO 30KT.
.LONG TERM...COOLER AIR WILL CONTINUE TO MOVE SOUTH INTO COLORADO
DURING MONDAY WITH HIGH TEMPERATURES ABOUT 15 DEGREES OR COOLER
OVER THE PLAINS COMPARED TO TODAY. MOUNTAINS WILL SEE LESS OF A
CHANGE..PERHAPS A FEW DEGREES COOLER. THIS FRONT IS DRY AND ONLY
SOME HIGH CLOUDS ARE EXPECTED. ALREADY BEGINNING MONDAY
NIGHT...WARMER AND DRIER AIR WILL MOVE INTO THE STATE FROM THE
BUILDING WEST COAST RIDGE. WITH A DEEPENING SURFACE LOW OVER THE
EASTERN PLAINS TUESDAY IN ADDITION TO THE WARM ADVECTION
ALOFT...EXPECT HIGH TEMPERATURES TO WARM BACK INTO THE 50S FOR THE
PLAINS AND 30S IN THE MOUNTAINS.
MODEL CONSISTENCY WITH THE NEXT SHORTWAVE OUT OF CANADA IS NOT THE
BEST...BUT THE OVERALL TREND IS TO HAVE MORE OF A PUSH. HAVE
COOLED TEMPERATURES BOTH FOR WEDNESDAY AND THURSDAY AND ADDED A
SLIGHT CHANCE OF FLURRIES WEDNESDAY NIGHT INTO THURSDAY AS THE
MOISTURE DEPTH DOESN`T LOOK ALL THAT GREAT. A STRONG SURFACE HIGH
WILL MOVE INTO THE NORTHERN GREAT PLAINS AND CONTINUE SOUTH
PUSHING COLDER AIR INTO THE STATE...DID NOT GO AS DRASTICALLY LOW
AS THE ECMWF WITH TEENS AS THE MAX TEMPS FOR THURSDAY...BUT STAYED
IN THE UPPER 30S TO LOWER 40S.
AN UPPER LOW THAT MOVED OVER THE PACIFIC NORTHWEST WEDNESDAY WILL
MOVE SOUTH THURSDAY THEN ALL THREE MODELS...EC...GFS AND GEM SHOW
THIS LOW RETROGRADING INTO THE PACIFIC THROUGH THE WEEKEND. THIS
LOW IS NOT EXPECTED TO HAVE MUCH MOISTURE WITH IT...SO PERHAPS
SOME LIGHT SNOW OVER THE MOUNTAINS THURSDAY INTO FRIDAY WHEN ITS
CLOSEST...THEN WE SHOULD DRY OUT AGAIN.
&&
.AVIATION...VFR WITH MOSTLY CLEAR SKIES TODAY. SOME HIGH CIRRUS THIS
AFTERNOON. GUSTY WEST WINDS AT BJC THIS AM IN THE 20-30KT RANGE
BUT WILL DECREASE A BIT THIS AFTERNOON. SURFACE WINDS AT APA/DEN
WILL BE SOUTH TO SOUTHWEST AND THEN SOME STRONGER W-NW WINDS
SURFACING BY AFTERNOON.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...ENTREKIN
LONG TERM....KRIEDERMAN
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
941 AM EST SUN JAN 19 2014
.UPDATE...THE MAIN FEATURE FOR TODAY WILL BE A SHORT WAVE PUSHING
A LINE OF SHOWERS THROUGH THE CENTRAL PENINSULA. GLOBAL MODELS
WERE NOT HANDLING THIS AREA OF SHOWERS AND ISOLATED STORMS VERY
WELL...HOWEVER LOCAL HI RES HRRR AND WRF ARE DEPICTING THIS LINE
TO PUSH THROUGH THE NATURE COAST THIS AFTERNOON BEFORE BEGINNING
TO FALL APART AS IT APPROACHES THE TAMPA BAY AREA. WILL SIDE WITH
THE LOCAL MODELS SO BUMPED UP POPS SIGNIFICANTLY FOR THE NORTHERN
HALF OF THE CWA. PARTS OF THE NATURE COAST MAY SEE AN ISOLATED
THUNDERSTORM BEFORE THE LINE MOVES SOUTH. ADDITIONALLY...BREEZY ON
SHORE WINDS ALONG AREA BEACHES WILL CREATE A RIP CURRENT RISK THROUGH
TONIGHT. A RIP CURRENT STATEMENT HAS BEEN ISSUED.
&&
.AVIATION...VFR CONDITIONS ARE GENERALLY EXPECTED THROUGH THE TAF
FORECAST PERIOD. A COLD FRONT WILL MOVE THROUGH THE AREA LATE THIS
AFTERNOON INTO EARLY THIS EVENING...RESULTING IN AN INCREASE IN
CLOUD COVER. ANY CEILINGS HOWEVER ARE EXPECTED TO REMAIN AT OR
ABOVE 3500 FEET. CAN/T RULE OUT AN ISOLATED SHOWER OR TWO
AFFECTING THE NORTHERN TERMINALS AHEAD OF THE COLD FRONT...BUT
WILL HOLD OFF ON MENTIONING IN THE TAFS UNTIL TIMING AND DURATION
BECOME MORE CLEAR.
&&
.MARINE...WEST WINDS TO PERSIST TODAY AND REMAIN AROUND 15 KNOTS.
WILL MAINTAIN THE SMALL CRAFT EXERCISE CAUTION HEADLINE FOR THE
NEXT UPDATE. FOR AREAS NORTH OF TAMPA BAY...INCREASED RAIN
POTENTIAL TODAY WITH A WEAK BOUNDARY SHIFTING THROUGH THE EASTERN
GULF. OTHERWISE... NO MAJOR UPDATES ANTICIPATED.
&&
.FIRE WEATHER...RED FLAG WARNING IN EFFECT TODAY FOR INLAND
CHARLOTTE AND LEE COUNTY. FOR THE MORNING UPDATE...INCREASED RAIN
POTENTIAL FOR THE NORTHERN HALF OF THE CWA BUT THIS WILL NOT REACH
THE RED FLAG WARNING AREA BY THE AFTERNOON. PATCHY FOG WILL BE
POSSIBLE FOR INLAND AREAS...MAINLY EAST OF I 75 TOMORROW MORNING
BEFORE SUNRISE. RH WILL MODERATE BY TOMORROW ACROSS THE AREA WITH
WEST TO NORTHWEST WINDS SUBSIDING.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 67 50 69 55 / 30 0 0 10
FMY 70 51 74 54 / 0 0 0 10
GIF 68 48 70 52 / 30 0 0 10
SRQ 69 50 70 54 / 30 0 0 10
BKV 68 37 70 45 / 30 0 0 10
SPG 67 54 69 57 / 30 0 0 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...RIP CURRENT RISK THROUGH THIS EVENING FOR COASTAL
CHARLOTTE-COASTAL LEE-COASTAL MANATEE-COASTAL
SARASOTA-PINELLAS.
RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 6 PM EST THIS
EVENING FOR INLAND CHARLOTTE-INLAND LEE.
GULF WATERS...NONE.
&&
$$
UPDATE/MARINE/FIRE WEATHER...20/BARRON
AVIATION...21/JELSEMA
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
910 AM EST SUN JAN 19 2014
.DISCUSSION...WEAK SURFACE HIGH CENTERED OVER THE SOUTHERN PENINSULA
THIS MORNING...WHICH KEPT WINDS CALM OVERNIGHT AND ALLOWED
TEMPERATURES TO BOTTOM OUT IN THE 30S ACROSS ALL BUT THE BARRIER
ISLANDS EARLIER THIS MORNING...WITH EVEN A FEW UPPER 20S IN SEVERAL
LOCATIONS.
AFTER THIS CHILLY START...TEMPERATURES HAVE ALREADY QUICKLY
RECOVERED INTO THE 40S UNDER CLEAR SKIES AND AFTERNOON HIGHS WILL
REACH SEASONAL NORMS IN THE UPPER 60S AND LOW 70S.
PRE-FRONTAL BAND OF SHOWERS AND STORMS MOVING ACROSS THE PANHANDLE
AND INTO THE BIG BEND REGION HAS HELD TOGETHER SO FAR BETTER THAN
MODELS PREVIOUSLY INDICATED. HOWEVER DESPITE THE SHARP TROUGH THAT
WILL DRIVE IT THROUGH THE STATE LATER TODAY...IT WILL BE RUNNING
INTO A VERY DRY AIRMASS OVER PENINSULA FLORIDA. MORNING SOUNDINGS
AROUND 0.30" AND RUC ANALYSIS SHOWS MID LAYER RH VALUES AT 20-40
PERCENT. HAVE ADDED A SLIGHT CHANCE FOR LIGHT SHOWERS ACROSS LAKE
AND NW VOLUSIA COUNTIES TO COVER ANY ACTIVITY THAT MANAGES TO HOLD
TOGETHER AS THIS BAND APPROACHES THIS AFTERNOON. FOR EVERYONE
ELSE...THE IMPACT WILL BE AN INCREASE IN CLOUDS THIS AFTERNOON.
&&
.AVIATION...VFR. WEST WINDS GUSTING TO 20-23 KTS THIS AFTERNOON. A
FEW -SHRA/SPRINKLES POSSIBLE NORTH OF I-4 AFTER 19Z WITH MINIMAL
IMPACT.
&&
.MARINE...WEST-NORTHWEST WINDS AROUND 15KTS THROUGH TONIGHT...THOUGH
SPEEDS MAY APPROACH 15-20 KTS OFFSHORE NORTH OF SEBASTIAN INLET THIS
AFTERNOON. STILL LOOKS LIKE A BRIEF PERIOD OF AROUND 20KTS WILL BE
POSSIBLE THIS EVENING NORTH OF THE CAPE...BUT CONFIDENCE NOT HIGH
ENOUGH AT THIS TIME TO WARRANT A SMALL CRAFT ADVISORY DUE TO SHORT
DURATION/MARGINAL NATURE OF EVENT. WILL KEEP WITH CAUTIONARY
STATEMENTS.
SEAS 2-3 FT NEAR SHORE/3-4 FT OFFSHORE/GULF STREAM WITH POTENTIAL OF
SOME 5 FT SEAS THIS EVENING OFFSHORE.
&&
.FIRE WEATHER...TODAY...LOW RELATIVE HUMIDITY VALUES ARE FORECAST TO
DROP INTO THE 30S AND LOW 40S ACROSS EAST CENTRAL FLORIDA. ANOTHER
COLD FRONT IS POISED TO MOVE THROUGH THE AREA LATE. WESTERLY 20 FOOT
WINDS BETWEEN 10-15 MPH WITH OCCASIONAL HIGHER GUSTS. DISPERSION
WILL BE GENERALLY GOOD THIS AFTERNOON.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE
AM...NONE.
&&
$$
MOSES/VOLKMER
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
615 AM EST SUN JAN 19 2014
.SYNOPSIS...
ISSUED AT 615 AM EST SUN JAN 19 2014
STRONG SOUTHWEST WINDS WILL DEVELOP THIS MORNING AND PERSIST THROUGH
THE AFTERNOON WITH GUSTS OF 35 TO 40 MPH POSSIBLE. THIS WILL LEAD
TO SIGNIFICANT BLOWING AND DRIFTING SNOW IN MANY AREAS. HIGHS THIS
AFTERNOON WILL RANGE FROM THE UPPER 20S EAST TO THE LOWER 30S
WEST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM EST SUN JAN 19 2014
EWD BREAKDOWN OF MEAN TROUGH THROUGH THE LAKES ON TAP THIS PD AS
CONUS HGT PATTN BRIEFLY RELAXES. HWVR THIS WILL YIELD PROBS TDA AS
LLJ RAMPS QUICKLY IN WAKE OF DEPARTING UPR JET LIFTING OUT THROUGH
THE ERN LAKES. PRIMARY QN IS HOW DEEP SFC BASED MIXED LYR CAN DVLP
OVERTOP DECENT SNOWPACK ACRS THE AREA. RUC ALG W/VARIOUS BUFR SNDG
DATA SUGGESTS SUFFICIENT MIXING TO TAP INTO MUCH HIGHER MOMENTUM AIR
JUST OFF THE DECK WITHIN A CORE OF 35KT FLW AT H95. THUS
W/POTENTIAL 35-40 MPH GUSTS...XPC SIG BLOWING/DRIFTING FM LATE
MORNING THROUGH MID AFTN BEFORE ABATING THIS EVENING.
SECONDARY CONCERNS EXIST THIS EVENING AHD OF NEXT CDFNT DROPPING SWD
ACRS THE LAKES. DEEPENING SFC BASED MOIST LYR ALG SFC CDFNT AND
SHALLOW ASCENT INDICATE A PD OF FZDZ PSBL BFR ADDNL SATURATION DEPTH
WITHIN COOLING LL COLUMN SPRTS -SHSN AND ADDED MENTION GIVEN GREATER
LIKELIHOOD OF FZDZ VS -SHSN OCCURRING UNTIL LT TONIGHT.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 333 AM EST SUN JAN 19 2014
VERY COLD PATTERN WILL PERSIST THIS PERIOD WITH REGION LOCKED IN
UNDER DEEP EASTERN CONUS LONGWAVE TROUGH AS UPPER RIDGE AMPLIFIES
ALONG THE WEST COAST OF NORTH AMERICA. NUMEROUS SHORTWAVES IN
PREVAILING NORTHWEST FLOW WILL BRING PERIODIC CHANCES FOR LIGHT
SNOW...WITH HEAVY LAKE EFFECT SNOW POSSIBLE IN WAKE OF SHORTWAVES
MON NIGHT/TUE AND AGAIN WED NIGHT/THU.
COLD ADVECTION WILL GRADUALLY DEEPEN BEHIND AN ARCTIC FRONT MON
WITH TEMPS STEADY/FALLING. STEEPENING LOW LEVEL LAPSE RATES IN
POST-FRONTAL ENVIRONMENT MAY SUPPORT A FEW FLURRIES OR LIGHT SNOW
SHOWERS...ESPECIALLY IN THE NORTHWEST WHERE LAKE ENHANCEMENT MAY
AFFORD SOME LIGHT ACCUMS. GUIDANCE IN DECENT AGREEMENT IN DROPPING
FIRST IN PARADE OF CLIPPER SYSTEMS AND SECONDARY SFC TROUGH THROUGH
LATE MONDAY AFTN/NIGHT. COULD SEE A QUICK 1-2" OF FLUFF WITH WAVE
GIVEN DEEP DGZ.
ATTENTION IN WAKE OF THIS WAVE WILL TURN TO BITTERLY COLD
TEMPERATURES (20 DEGREES BELOW NORMAL) TUE-WED AND POTENTIAL
SIGNIFICANT LAKE EFFECT SNOW EVENT MON NIGHT-TUE MORNING IN FAR NW
INDIANA/SW LOWER MI. SYNOPTIC FLOW LOCKS IN NORTHERLY DURING THIS
TIME WITH EXTREME OVER LAKE INSTABILITY AND FLOW DIRECTED PARALLEL
TO LONG AXIS OF LAKE LIKELY SUPPORTING STRONG CONVERGENCE. EXPECT
EXCELLENT SNOW GROWTH / RATIOS 30:1 OR SO / WITH OMEGA BULLSEYE IN
UPPER PORTION OF DGZ. MESOSCALE PROCESSES (MESOLOW DEVELOPMENT/LAND
BREEZE/AGGREGATE TROUGHING/ETC) WILL NO DOUBT MODULATE CONVECTIVE
LAYER TRAJECTORIES AND WHERE POTENTIAL INTENSE SINGLE BAND WILL SET
UP. WILL CONTINUE TO HIGHLIGHT THE THREAT FOR HEAVY LAKE EFFECT SNOW
IN THE HWO AND HOLD OFF ON ANY PERIOD 4 HEADLINES GIVEN NORMAL LAKE
EFFECT UNCERTAINTIES REGARDING PLACEMENT/TIMING...WITH BEST CHANCES
FOR WARNING LEVEL SNOWS/IMPACTS IN LA PORTE/STARKE/WESTERN ST JOE
IN/BERRIEN COUNTIES.
NEXT PV ANOMALY DIGS SOUTHEAST THROUGH THE LOWER GREAT LAKES WED-WED
EVE WITH NEXT OPPORTUNITY FOR WIDESPREAD LIGHT SNOW
ACCUMULATIONS...POSSIBLY FOLLOWED UP BY ANOTHER SIGNIFICANT LAKE
EFFECT/ENHANCED SNOW EVENT LATER WED NIGHT-THU. AND YEP...ANOTHER
SHORTWAVE AND REINFORCING SHOT OF ARCTIC AIR BY LATER FRI INTO SAT
PER LAST SEVERAL MODEL CYCLES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 615 AM EST SUN JAN 19 2014
SECONDARY BAND OF STRATUS THINNING RAPIDLY ALG WRN FLANK IN
RESPONSE TO SUBSIDENCE ASSOCD/W LEAD BAND OF MID-HIGH CLDS ADVTG
SEWD OUT OF WI. OTRWS PRIMARY PROB THIS PD CONTS TO BE RAPID SEWD
DVLPMNT OF STG LLJ CORE IN WAKE OF DEPARTING UPR JET STREAK
LIFTING OUT THROUGH THE ERN LAKES AND NOTED IN UPSTREAM VWP PLOTS.
RETAINED PRIOR LLWS MENTION ISSUANCE FOR XPCD TURBULENT BNDRY LYR
FLW DVLPG AFT SUNRISE AND PEAKING THIS AFTN W/SFC GUSTS AOA 30KTS
LIKELY. LOW BLOWING AND DRIFTING WILL BE PROBLEMATIC 15-21Z.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR LMZ043-046.
&&
$$
SYNOPSIS...T
SHORT TERM...T
LONG TERM...STEINWEDEL
AVIATION...T
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1010 AM EST SUN JAN 19 2014
.SYNOPSIS...
A DISTURBANCE IN THE JET STREAM WINDS ALOFT AND AN ARCTIC COLD
FRONT WILL PRODUCE PERIODS OF SNOW SHOWERS ACROSS THE NORTH
COUNTRY TODAY AND TONIGHT. OVERALL...SNOW ACCUMULATIONS WILL BE
LIGHT WITH 1 TO 3 INCHES IN GENERAL EXPECTED. BEHIND THE
FRONT...A RETURN OF MUCH COLDER AND DRIER CONDITIONS IS EXPECTED
FOR THE UPCOMING WEEK...WITH HIGHS ONLY IN THE SINGLE DIGITS
ABOVE ZERO AND LOWS IN THE SINGLE DIGITS TO TEENS BELOW FOR
MONDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 955 AM EST SUNDAY...SUFFICIENT MOISTURE ACROSS REGION THIS
MORNING...AND THIS COUPLED WITH SHORTWAVE TROUGH AND WARM AIR
ADVECTION HAS RESULTED IN RATHER WIDESPREAD LIGHT SNOW ACROSS THE
AREA...WITH SNOWFALL AMOUNTS ANYWHERE FROM A TRACE TO 3 INCHES.
AS SHORTWAVE DEPARTS THE AREA TOWARDS MIDDAY...LOOK FOR A DECREASE
IN PRECIPITATION OVER MUCH OF THE REGION. EXCEPTION WILL BE ACROSS
SAINT LAWRENCE VALLEY AND ADIRONDACKS WHERE PERSISTENT SOUTHWEST
FLOW WILL RESULT IN LIKELIHOOD OF MORE SNOW SHOWERS THIS
AFTERNOON. ACTIVITY WILL THEN INCREASE ACROSS THE REST OF THE REST
OF THE FORECAST AREA ONCE AGAIN LATER THIS AFTERNOON AND
ESPECIALLY THIS EVENING WITH APPROACH OF ARCTIC FRONT. GOING
FORECAST HAS THIS ALL COVERED FAIRLY WELL...SO NO SIGNIFICANT
CHANGES WITH LATEST UPDATE. HAVE UPDATED TEMPS TO REFLECT LATEST
CONDITIONS...BUT MAX TEMPS IN THE UPPER 20S TO LOWER 30S STILL
LOOK TO BE ON TRACK.
EARLIER DISCUSSION...
VERY LITTLE OVERALL CHANGE FROM PREVIOUS FORECAST THINKING FOR
TODAY AS THE ATMOSPHERE IS BEHAVING MUCH LIKE WE EXPECTED. LATEST
GUIDANCE CONTINUES TO SLOW DOWN THE APPROACH OF AN ARCTIC FRONT
WHICH NOW LOOKS TO AFFECT THE NORTH COUNTRY TOWARD THIS EVENING
AND TONIGHT...SO FOR TODAY WE`LL BE DEALING WITH A POTENT
SHORTWAVE TROUGH CURRENTLY OVER THE OHIO RIVER VALLEY WHICH WILL
SHIFT EASTWARD THROUGH THE MID-ATLANTIC STATES. LATEST WV IMAGERY
CONTINUES TO SUPPORT THE IDEA THAT THE BEST PVA SLIDES TO OUR
SOUTH TODAY...BUT 13KM RAP CONTINUES TO SHOW A PIECE OF ENERGY
BREAKING OFF AND TRACKING NORTHEAST THROUGH THE CWA THIS MORNING.
WITH THE EXCEPTIONAL PERFORMANCE OF THE RAP OVER THE LAST FEW DAYS
IT`S HARD TO IGNORE IT...AND OVERALL IT MAKES SENSE BASED ON THE
UPPER FLOW TRENDING SOUTHWESTERLY. THAT SAID...WE`LL SEE PERIODS
OF SNOW SHOWERS THIS MORNING THROUGH ABOUT MID-DAY...WITH A BREAK
IN THE ACTION THIS AFTERNOON AS THE SHORTWAVE ENERGY SHIFTS
NORTHEAST OF THE REGION AND WE AWAKE ANOTHER ROUND OF SNOW SHOWERS
ASSOCIATED WITH THE ARCTIC FRONT. OVERALL QPF WILL BE VERY LIGHT
WITH JUST A FEW HUNDREDTHS OF LIQUID EXPECTED...AMOUNTING TO JUST
A DUSTING TO MAYBE 2 INCHES THROUGH THE DAY. TEMPS WILL BE THE
LAST ABOVE NORMALS WE`LL SEE FOR AWHILE AND GENERALLY IN THE 20S
TO A FEW LOW 30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
AS OF 340 AM EST SUNDAY...FOR TONIGHT INTO MONDAY FOCUS TURNS
TOWARDS AN ARCTIC BOUNDARY WHICH WILL SWING NORTHWEST TO
SOUTHEAST THROUGH THE CWA. AS MENTIONED ABOVE...LATEST GUIDANCE
CONTINUES TO SLOW THE PROGRESSION OF SAID FEATURE WITH SOME
RESIDUAL LAKE ENHANCED SNOW SHOWERS NOW POSSIBLY LINGERING
THROUGH MID-DAY MONDAY ACROSS CENTRAL AND SOUTHERN AREAS.
OVERALL...FRONT SHOULD MOVE INTO NORTHWESTERN PORTIONS OF THE
REGION LATE THIS EVENING WITH LOCAL WRF`S AND RAP CONTINUING TO
SHOW FAVORABLE CONDITIONS FOR SNOW SQUALLS. THINKING ANOTHER
DUSTING TO 2 INCHES WILL BE POSSIBLE TONIGHT...WITH MUCH OF THAT
LIKELY OCCURRING IN A VERY SHORT PERIOD OF TIME. COME MONDAY
MORNING FRONT WILL BE SOMEWHERE ACROSS CENTRAL AND SOUTHERN
VERMONT WITH SOME LINGERING LAKE ENHANCED SHOWERS SHOWERS AROUND
ESPECIALLY ACROSS THE HIGHER TERRAIN...BUT AS DRIER AIR MOVES IN
UNDER STRONG CAA ON NORTHWEST FLOW SNOW SHOULD TAPER OFF BY THE
AFTERNOON HOURS. DAYTIME HIGHS IN THE TEENS WILL LIKELY BE
REACHED DURING THE MORNING HOURS...SLOWLY FALLING THROUGH THE DAY
WITH THE EXCEPTION BEING THE FAR SOUTHEAST CORNER OF VT WHERE
HIGHS WILL BE IN THE MID 20S AHEAD OF THE FRONT.
FOR MONDAY NIGHT AND TUESDAY SURFACE HIGH PRESSURE BUILDS INTO
THE REGION WITH CLEARING SKIES AND BONE CHILLING TEMPERATURES
EXPECTED. MONDAY NIGHT LOWS WILL FALL INTO THE SINGLE DIGIT TO
TEENS BELOW ZERO...AND WITH MODERATE GRADIENT FLOW REMAINING
BETWEEN THE BUILDING HIGH AND DEPARTING LOW WE`LL LIKELY BE
LOOKING AT SOME WIND CHILL ADVISORIES FOR PORTIONS OF NORTHERN
NEW YORK AND NORTHEAST VERMONT. WINDS WILL SLACKEN OFF FOR TUESDAY
WITH PARTLY SUNNY SKIES AND HIGHS ONLY IN THE THE SINGLE DIGITS
BELOW TO 10 ABOVE.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 212 AM EST SUNDAY...QUIET...COLD AND MAINLY DRY PATTERN WILL
BECOME LOCKED IN ACROSS THE EASTERN HALF OF THE U.S. DURING THE
MID TO LATE WEEK TIME FRAME AND LIKELY BEYOND AS ARCTIC AIR HAS A
DIRECT PATHWAY INTO OUR REGION. THIS IS A VERY STABLE
PATTERN...AND UNTIL MORE ORGANIZED ENERGY CAN CRASH EASTWARD
THROUGH THE HIGH-AMPLITUDE WESTERN CONUS RIDGE...THE CURRENT HIGH
AMPLITUDE PATTERN SHOULD MORE OR LESS HOLD IN PLACE FOR THE NEXT
10 DAYS. IN TERMS OF SENSIBLE WEATHER...TEMPERATURES WILL REMAIN
WELL BELOW NORMAL WEDNESDAY INTO FRIDAY THOUGH WITH SOME SLIGHT
AIRMASS MODERATION BY ABOUT 5 DEGREES EACH DAY. OVERNIGHT LOWS
CONSISTENTLY BELOW ZERO WITH COLDEST NIGHT OCCURRING TUESDAY NIGHT
WHEN WIDESPREAD 10 TO 20 BELOW READINGS LIKELY. A WEAK CLIPPER LOW
PASSING SOUTH OF THE AREA MAY SPREAD SOME CLOUDINESS AND PERHAPS A
BRIEF PERIOD OF FLURRIES/VERY LIGHT SNOW TO OUR SOUTHERN COUNTIES
ON THURSDAY...OTHERWISE MAINLY DRY WEATHER IS EXPECTED THROUGH
FRIDAY.
BY FRIDAY NIGHT SOUTHERLY FLOW RETURNS AS SFC RIDGE DEPARTS EAST
ALLOWING TEMPERATURES TO CLIMB SLOWLY...REACHING NEAR MID-WINTER
SEASONAL NORMS FOR ONE BRIEF DAY ON SATURDAY. ADDITIONAL NORTHERN
STREAM ENERGY ACCOMPANIED BY YET ANOTHER IMPRESSIVE ARCTIC BOUNDARY
TO THEN SWEEP INTO THE REGION BY LATER SATURDAY/SATURDAY NIGHT WHERE
I`LL MAINTAIN SOLID CHC POPS FOR SLIGHTLY BETTER COVERAGE OF SHSN.
BEHIND THIS FRONT...ALL INDICATIONS SUGGEST WE`LL ONCE AGAIN ENTER
THE DEEP FREEZE FOR AT LEAST A FEW MORE DAYS FROM NEXT SUNDAY ONWARD
AS ARCTIC HIGH PRESSURE REASSERTS ITSELF ACROSS THE NORTHEAST. WISH
I COULD PAINT A MORE INTERESTING AND/OR COMFORTABLE PATTERN...BUT
ALL INDICATIONS SUGGEST VERY COLD AND DRY THROUGH THE END OF THE
MONTH.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
THROUGH 12Z MONDAY...VRB CONDS OF VFR/MVFR/OCCNL IFR EXPECTED OVER
THE NEXT 24 HOURS AS SCT LIGHT SNOWS/FLURRIES AFFECT THE REGION
THROUGH 18Z...THEN MORE DISCRETE BANDS/AREAS OF SHSN AND POSSIBLE
SQUALLS AFTER 00Z WITH APPROACH/PASSAGE OF ARCTIC COLD FRONT.
WITH PASSAGE OF ARCTIC FRONT BANDED HEAVIER SHSN/SQUALLS LIKELY
DURING A 1-2 HOUR PERIOD IN WHICH BRIEF LIFR CONDS POSSIBLE AT ALL
TERMINALS. HOWEVER GIVEN THE FACT THAT THIS WILL GENERALLY OCCUR
IN THE 03-09Z TIME FRAME ON MONDAY AND FOR ONLY A BRIEF PERIOD OF
TIME...KEPT MORE GENERIC SHSN WORDING IN TERMINAL FORECASTS AT
THIS POINT UNTIL HIGHER CONFIDENCE OF TIMING OCCURS LATER TODAY.
WINDS GENERALLY LIGHT SOUTH TO SOUTHWESTERLY...INCREASING INTO THE
10 TO 20 KT RANGE AND TRENDING QUITE GUSTY INTO THE AFTERNOON/EVENING
HOURS AHEAD OF THE FRONT...ESP AT KBTV/KSLK/KMSS. BEHIND THE
FRONT...A WIND SHIFT TO WEST/NORTHWEST WITH SPEEDS SLOWLY ABATING
AT NORTHERN TERMINALS LATE.
OUTLOOK 12Z MONDAY THROUGH THURSDAY...
12Z MONDAY THROUGH 18Z MONDAY...TRENDING VFR THOUGH SOME LINGERING
MVFR/IFR SHSN POSSIBLE AS ARCTIC FRONT CLEARS SOUTH OF THE REGION.
18Z MONDAY ONWARD...MAINLY VFR WITH HIGH PRESSURE.
&&
.EQUIPMENT...
AS OF 340 AM EST SUNDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM BUT IT WILL
LIKELY BE OUT OF SERVICE THROUGH AT LEAST TUESDAY JANUARY 21.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...RJS/LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...JMG
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
635 AM EST SUN JAN 19 2014
.SYNOPSIS...
A DISTURBANCE IN THE JET STREAM WINDS ALOFT AND AN ARCTIC COLD
FRONT WILL PRODUCE PERIODS OF SNOW SHOWERS ACROSS THE NORTH
COUNTRY TODAY AND TONIGHT. OVERALL...SNOW ACCUMULATIONS WILL BE
LIGHT WITH 1 TO 3 INCHES IN GENERAL EXPECTED. BEHIND THE
FRONT...A RETURN OF MUCH COLDER AND DRIER CONDITIONS IS EXPECTED
FOR THE UPCOMING WEEK...WITH HIGHS ONLY IN THE SINGLE DIGITS
ABOVE ZERO AND LOWS IN THE SINGLE DIGITS TO TEENS BELOW FOR
MONDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 340 AM EST SUNDAY...VERY LITTLE OVERALL CHANGE FROM
PREVIOUS FORECAST THINKING FOR TODAY AS THE ATMOSPHERE IS
BEHAVING MUCH LIKE WE EXPECTED. LATEST GUIDANCE CONTINUES TO SLOW
DOWN THE APPROACH OF AN ARCTIC FRONT WHICH NOW LOOKS TO AFFECT
THE NORTH COUNTRY TOWARD THIS EVENING AND TONIGHT...SO FOR TODAY
WE`LL BE DEALING WITH A POTENT SHORTWAVE TROUGH CURRENTLY OVER
THE OHIO RIVER VALLEY WHICH WILL SHIFT EASTWARD THROUGH THE MID-
ATLANTIC STATES. LATEST WV IMAGERY CONTINUES TO SUPPORT THE IDEA
THAT THE BEST PVA SLIDES TO OUR SOUTH TODAY...BUT 13KM RAP
CONTINUES TO SHOW A PIECE OF ENERGY BREAKING OFF AND TRACKING
NORTHEAST THROUGH THE CWA THIS MORNING. WITH THE EXCEPTIONAL
PERFORMANCE OF THE RAP OVER THE LAST FEW DAYS IT`S HARD TO IGNORE
IT...AND OVERALL IT MAKES SENSE BASED ON THE UPPER FLOW TRENDING
SOUTHWESTERLY. THAT SAID...WE`LL SEE PERIODS OF SNOW SHOWERS THIS
MORNING THROUGH ABOUT MID-DAY...WITH A BREAK IN THE ACTION THIS
AFTERNOON AS THE SHORTWAVE ENERGY SHIFTS NORTHEAST OF THE REGION
AND WE AWAKE ANOTHER ROUND OF SNOW SHOWERS ASSOCIATED WITH THE
ARCTIC FRONT. OVERALL QPF WILL BE VERY LIGHT WITH JUST A FEW
HUNDREDTHS OF LIQUID EXPECTED...AMOUNTING TO JUST A DUSTING TO
MAYBE 2 INCHES THROUGH THE DAY. TEMPS WILL BE THE LAST ABOVE
NORMALS WE`LL SEE FOR AWHILE AND GENERALLY IN THE 20S TO A FEW
LOW 30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
AS OF 340 AM EST SUNDAY...FOR TONIGHT INTO MONDAY FOCUS TURNS
TOWARDS AN ARCTIC BOUNDARY WHICH WILL SWING NORTHWEST TO
SOUTHEAST THROUGH THE CWA. AS MENTIONED ABOVE...LATEST GUIDANCE
CONTINUES TO SLOW THE PROGRESSION OF SAID FEATURE WITH SOME
RESIDUAL LAKE ENHANCED SNOW SHOWERS NOW POSSIBLY LINGERING
THROUGH MID-DAY MONDAY ACROSS CENTRAL AND SOUTHERN AREAS.
OVERALL...FRONT SHOULD MOVE INTO NORTHWESTERN PORTIONS OF THE
REGION LATE THIS EVENING WITH LOCAL WRF`S AND RAP CONTINUING TO
SHOW FAVORABLE CONDITIONS FOR SNOW SQUALLS. THINKING ANOTHER
DUSTING TO 2 INCHES WILL BE POSSIBLE TONIGHT...WITH MUCH OF THAT
LIKELY OCCURRING IN A VERY SHORT PERIOD OF TIME. COME MONDAY
MORNING FRONT WILL BE SOMEWHERE ACROSS CENTRAL AND SOUTHERN
VERMONT WITH SOME LINGERING LAKE ENHANCED SHOWERS SHOWERS AROUND
ESPECIALLY ACROSS THE HIGHER TERRAIN...BUT AS DRIER AIR MOVES IN
UNDER STRONG CAA ON NORTHWEST FLOW SNOW SHOULD TAPER OFF BY THE
AFTERNOON HOURS. DAYTIME HIGHS IN THE TEENS WILL LIKELY BE
REACHED DURING THE MORNING HOURS...SLOWLY FALLING THROUGH THE DAY
WITH THE EXCEPTION BEING THE FAR SOUTHEAST CORNER OF VT WHERE
HIGHS WILL BE IN THE MID 20S AHEAD OF THE FRONT.
FOR MONDAY NIGHT AND TUESDAY SURFACE HIGH PRESSURE BUILDS INTO
THE REGION WITH CLEARING SKIES AND BONE CHILLING TEMPERATURES
EXPECTED. MONDAY NIGHT LOWS WILL FALL INTO THE SINGLE DIGIT TO
TEENS BELOW ZERO...AND WITH MODERATE GRADIENT FLOW REMAINING
BETWEEN THE BUILDING HIGH AND DEPARTING LOW WE`LL LIKELY BE
LOOKING AT SOME WIND CHILL ADVISORIES FOR PORTIONS OF NORTHERN
NEW YORK AND NORTHEAST VERMONT. WINDS WILL SLACKEN OFF FOR TUESDAY
WITH PARTLY SUNNY SKIES AND HIGHS ONLY IN THE THE SINGLE DIGITS
BELOW TO 10 ABOVE.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 212 AM EST SUNDAY...QUIET...COLD AND MAINLY DRY PATTERN WILL
BECOME LOCKED IN ACROSS THE EASTERN HALF OF THE U.S. DURING THE
MID TO LATE WEEK TIME FRAME AND LIKELY BEYOND AS ARCTIC AIR HAS A
DIRECT PATHWAY INTO OUR REGION. THIS IS A VERY STABLE
PATTERN...AND UNTIL MORE ORGANIZED ENERGY CAN CRASH EASTWARD
THROUGH THE HIGH-AMPLITUDE WESTERN CONUS RIDGE...THE CURRENT HIGH
AMPLITUDE PATTERN SHOULD MORE OR LESS HOLD IN PLACE FOR THE NEXT
10 DAYS. IN TERMS OF SENSIBLE WEATHER...TEMPERATURES WILL REMAIN
WELL BELOW NORMAL WEDNESDAY INTO FRIDAY THOUGH WITH SOME SLIGHT
AIRMASS MODERATION BY ABOUT 5 DEGREES EACH DAY. OVERNIGHT LOWS
CONSISTENTLY BELOW ZERO WITH COLDEST NIGHT OCCURRING TUESDAY NIGHT
WHEN WIDESPREAD 10 TO 20 BELOW READINGS LIKELY. A WEAK CLIPPER LOW
PASSING SOUTH OF THE AREA MAY SPREAD SOME CLOUDINESS AND PERHAPS A
BRIEF PERIOD OF FLURRIES/VERY LIGHT SNOW TO OUR SOUTHERN COUNTIES
ON THURSDAY...OTHERWISE MAINLY DRY WEATHER IS EXPECTED THROUGH
FRIDAY.
BY FRIDAY NIGHT SOUTHERLY FLOW RETURNS AS SFC RIDGE DEPARTS EAST
ALLOWING TEMPERATURES TO CLIMB SLOWLY...REACHING NEAR MID-WINTER
SEASONAL NORMS FOR ONE BRIEF DAY ON SATURDAY. ADDITIONAL NORTHERN
STREAM ENERGY ACCOMPANIED BY YET ANOTHER IMPRESSIVE ARCTIC BOUNDARY
TO THEN SWEEP INTO THE REGION BY LATER SATURDAY/SATURDAY NIGHT WHERE
I`LL MAINTAIN SOLID CHC POPS FOR SLIGHTLY BETTER COVERAGE OF SHSN.
BEHIND THIS FRONT...ALL INDICATIONS SUGGEST WE`LL ONCE AGAIN ENTER
THE DEEP FREEZE FOR AT LEAST A FEW MORE DAYS FROM NEXT SUNDAY ONWARD
AS ARCTIC HIGH PRESSURE REASSERTS ITSELF ACROSS THE NORTHEAST. WISH
I COULD PAINT A MORE INTERESTING AND/OR COMFORTABLE PATTERN...BUT
ALL INDICATIONS SUGGEST VERY COLD AND DRY THROUGH THE END OF THE
MONTH.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
THROUGH 12Z MONDAY...VRB CONDS OF VFR/MVFR/OCCNL IFR EXPECTED OVER
THE NEXT 24 HOURS AS SCT LIGHT SNOWS/FLURRIES AFFECT THE REGION
THROUGH 18Z...THEN MORE DISCRETE BANDS/AREAS OF SHSN AND POSSIBLE
SQUALLS AFTER 00Z WITH APPROACH/PASSAGE OF ARCTIC COLD FRONT.
WITH PASSAGE OF ARCTIC FRONT BANDED HEAVIER SHSN/SQUALLS LIKELY
DURING A 1-2 HOUR PERIOD IN WHICH BRIEF LIFR CONDS POSSIBLE AT ALL
TERMINALS. HOWEVER GIVEN THE FACT THAT THIS WILL GENERALLY OCCUR
IN THE 03-09Z TIME FRAME ON MONDAY AND FOR ONLY A BRIEF PERIOD OF
TIME...KEPT MORE GENERIC SHSN WORDING IN TERMINAL FORECASTS AT
THIS POINT UNTIL HIGHER CONFIDENCE OF TIMING OCCURS LATER TODAY.
WINDS GENERALLY LIGHT SOUTH TO SOUTHWESTERLY...INCREASING INTO THE
10 TO 20 KT RANGE AND TRENDING QUITE GUSTY INTO THE AFTERNOON/EVENING
HOURS AHEAD OF THE FRONT...ESP AT KBTV/KSLK/KMSS. BEHIND THE
FRONT...A WIND SHIFT TO WEST/NORTHWEST WITH SPEEDS SLOWLY ABATING
AT NORTHERN TERMINALS LATE.
OUTLOOK 12Z MONDAY THROUGH THURSDAY...
12Z MONDAY THROUGH 18Z MONDAY...TRENDING VFR THOUGH SOME LINGERING
MVFR/IFR SHSN POSSIBLE AS ARCTIC FRONT CLEARS SOUTH OF THE REGION.
18Z MONDAY ONWARD...MAINLY VFR WITH HIGH PRESSURE.
&&
.EQUIPMENT...
AS OF 340 AM EST SUNDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM BUT IT WILL
LIKELY BE OUT OF SERVICE THROUGH AT LEAST TUESDAY JANUARY 21.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...JMG
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1024 AM MST SUN JAN 19 2014
.UPDATE...SKIES WILL REMAIN SUNNY THROUGH TODAY EXCEPT FOR A BAND
OF HIGH CLOUDS MOVING SOUTHWARD FROM WYOMING. SURFACE PRESSURE
GRADIENTS WILL CONTINUE RELAXING THROUGH THE DAY...LEADING TO LESS
WIND OVER THE FOOTHILLS AS THE AFTERNOON WEARS ON. HIGH
TEMPERATURES IN THE LOWER TO MID 60S THIS AFTERNOON LOOKS TO BE
ON TRACK.
&&
.AVIATION...NO AVIATION IMPACTS EXPECTED. SOME WEST WINDS TODAY
AND MORE SOUTHERLIES TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 410 AM MST SUN JAN 19 2014/
SHORT TERM...BROAD UPPER RIDGING HAS NUDGED INLAND A BIT ALONG
THE WEST COAST WITH RESULTANT DECREASING NORTHWEST FLOW ALOFT
OVER COLORADO. AIRMASS IS QUITE DRY AND STABLE BUT THERE IS A WEAK
RIPPLE WHICH WILL RESULT IN JUST SOME HIGH CLOUDS AT TIMES LATER
THIS AM AND AFTERNOON. AIRMASS WILL CONTINUE TO WARM TODAY AS
700MB TEMPS RISE TO AROUND +3C WHICH WILL ALLOW TEMPERATURES TO
CLIMB INTO THE LOWER AND MID 60S OVER THE PLAINS. RECORD HIGH IN
DENVER IS 68 TODAY BUT DON`T THINK WILL GET QUITE THAT WARM. THERE
WILL BE SOME GUSTY WINDS OVER THE EAST SLOPES AND BASE OF THE
FOOTHILLS THIS MORNING WITH MODEST STABLE INVERSION AT 700MB THIS
AM. ALREADY SEEING SOME GUSTS IN THE 30-40KT RANGE IN THE
NORTHERN FRONT RANGE FOOTHILLS. LATEST RAP CROSS SECTIONS SHOWING
WINDS DECREASING THIS AFTERNOON BUT STILL A DECENT SURFACE
GRADIENT IN PLACE THROUGH MUCH OF THE DAY. AS LOW LEVELS MIX OUT
COULD STILL SEE GUSTY WINDS OVER THE NORTHEAST PLAINS TO 30KT.
LONG TERM...COOLER AIR WILL CONTINUE TO MOVE SOUTH INTO COLORADO
DURING MONDAY WITH HIGH TEMPERATURES ABOUT 15 DEGREES OR COOLER
OVER THE PLAINS COMPARED TO TODAY. MOUNTAINS WILL SEE LESS OF A
CHANGE..PERHAPS A FEW DEGREES COOLER. THIS FRONT IS DRY AND ONLY
SOME HIGH CLOUDS ARE EXPECTED. ALREADY BEGINNING MONDAY
NIGHT...WARMER AND DRIER AIR WILL MOVE INTO THE STATE FROM THE
BUILDING WEST COAST RIDGE. WITH A DEEPENING SURFACE LOW OVER THE
EASTERN PLAINS TUESDAY IN ADDITION TO THE WARM ADVECTION
ALOFT...EXPECT HIGH TEMPERATURES TO WARM BACK INTO THE 50S FOR THE
PLAINS AND 30S IN THE MOUNTAINS.
MODEL CONSISTENCY WITH THE NEXT SHORTWAVE OUT OF CANADA IS NOT THE
BEST...BUT THE OVERALL TREND IS TO HAVE MORE OF A PUSH. HAVE
COOLED TEMPERATURES BOTH FOR WEDNESDAY AND THURSDAY AND ADDED A
SLIGHT CHANCE OF FLURRIES WEDNESDAY NIGHT INTO THURSDAY AS THE
MOISTURE DEPTH DOESN`T LOOK ALL THAT GREAT. A STRONG SURFACE HIGH
WILL MOVE INTO THE NORTHERN GREAT PLAINS AND CONTINUE SOUTH
PUSHING COLDER AIR INTO THE STATE...DID NOT GO AS DRASTICALLY LOW
AS THE ECMWF WITH TEENS AS THE MAX TEMPS FOR THURSDAY...BUT STAYED
IN THE UPPER 30S TO LOWER 40S.
AN UPPER LOW THAT MOVED OVER THE PACIFIC NORTHWEST WEDNESDAY WILL
MOVE SOUTH THURSDAY THEN ALL THREE MODELS...EC...GFS AND GEM SHOW
THIS LOW RETROGRADING INTO THE PACIFIC THROUGH THE WEEKEND. THIS
LOW IS NOT EXPECTED TO HAVE MUCH MOISTURE WITH IT...SO PERHAPS
SOME LIGHT SNOW OVER THE MOUNTAINS THURSDAY INTO FRIDAY WHEN ITS
CLOSEST...THEN WE SHOULD DRY OUT AGAIN.
AVIATION...VFR WITH MOSTLY CLEAR SKIES TODAY. SOME HIGH CIRRUS THIS
AFTERNOON. GUSTY WEST WINDS AT BJC THIS AM IN THE 20-30KT RANGE
BUT WILL DECREASE A BIT THIS AFTERNOON. SURFACE WINDS AT APA/DEN
WILL BE SOUTH TO SOUTHWEST AND THEN SOME STRONGER W-NW WINDS
SURFACING BY AFTERNOON.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...DANKERS
LONG TERM....99
AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1246 PM EST SUN JAN 19 2014
.SYNOPSIS...
ISSUED AT 1245 PM EST SUN JAN 19 2014
STRONG SOUTHWEST WINDS WILL PERSIST THROUGH THE AFTERNOON WITH
GUSTS OF 35 TO 40 MPH POSSIBLE. THIS WILL LEAD TO SIGNIFICANT
BLOWING AND DRIFTING SNOW IN MANY AREAS. HIGHS THIS AFTERNOON WILL
RANGE FROM THE UPPER 20S EAST TO THE LOWER 30S WEST.
&&
.UPDATE...
ISSUED AT 1236 PM EST SUN JAN 19 2014
GUSTY WINDS ARRIVED ON SCHEDULE IN MOST AREAS AS CLEARING WAS
WORKING SLOWLY FROM WEST TO EAST. THE GUSTY WINDS HAVE BEEN
CAUSING WIDESPREAD DRIFTING SNOW AND POCKETS OF BLOWING SNOW WITH
SOME SITES DROPPING BELOW 2 MIELS AT TIMES. SPS WAS ISSUED EARLIER
THROUGH LATE AFTERNOON TO ADDRESS CONCERNS. TEMPS HAVE BEEN SLOW
TO RISE NE AREAS WITH CLOUD COVER. ALL AREAS SHOULD GET WITHIN A
FEW DEGREES OF FORECAST HIGHS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM EST SUN JAN 19 2014
EWD BREAKDOWN OF MEAN TROUGH THROUGH THE LAKES ON TAP THIS PD AS
CONUS HGT PATTN BRIEFLY RELAXES. HWVR THIS WILL YIELD PROBS TDA AS
LLJ RAMPS QUICKLY IN WAKE OF DEPARTING UPR JET LIFTING OUT THROUGH
THE ERN LAKES. PRIMARY QN IS HOW DEEP SFC BASED MIXED LYR CAN DVLP
OVERTOP DECENT SNOWPACK ACRS THE AREA. RUC ALG W/VARIOUS BUFR SNDG
DATA SUGGESTS SUFFICIENT MIXING TO TAP INTO MUCH HIGHER MOMENTUM AIR
JUST OFF THE DECK WITHIN A CORE OF 35KT FLW AT H95. THUS
W/POTENTIAL 35-40 MPH GUSTS...XPC SIG BLOWING/DRIFTING FM LATE
MORNING THROUGH MID AFTN BEFORE ABATING THIS EVENING.
SECONDARY CONCERNS EXIST THIS EVENING AHD OF NEXT CDFNT DROPPING SWD
ACRS THE LAKES. DEEPENING SFC BASED MOIST LYR ALG SFC CDFNT AND
SHALLOW ASCENT INDICATE A PD OF FZDZ PSBL BFR ADDNL SATURATION DEPTH
WITHIN COOLING LL COLUMN SPRTS -SHSN AND ADDED MENTION GIVEN GREATER
LIKELIHOOD OF FZDZ VS -SHSN OCCURRING UNTIL LT TONIGHT.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 333 AM EST SUN JAN 19 2014
VERY COLD PATTERN WILL PERSIST THIS PERIOD WITH REGION LOCKED IN
UNDER DEEP EASTERN CONUS LONGWAVE TROUGH AS UPPER RIDGE AMPLIFIES
ALONG THE WEST COAST OF NORTH AMERICA. NUMEROUS SHORTWAVES IN
PREVAILING NORTHWEST FLOW WILL BRING PERIODIC CHANCES FOR LIGHT
SNOW...WITH HEAVY LAKE EFFECT SNOW POSSIBLE IN WAKE OF SHORTWAVES
MON NIGHT/TUE AND AGAIN WED NIGHT/THU.
COLD ADVECTION WILL GRADUALLY DEEPEN BEHIND AN ARCTIC FRONT MON
WITH TEMPS STEADY/FALLING. STEEPENING LOW LEVEL LAPSE RATES IN
POST-FRONTAL ENVIRONMENT MAY SUPPORT A FEW FLURRIES OR LIGHT SNOW
SHOWERS...ESPECIALLY IN THE NORTHWEST WHERE LAKE ENHANCEMENT MAY
AFFORD SOME LIGHT ACCUMS. GUIDANCE IN DECENT AGREEMENT IN DROPPING
FIRST IN PARADE OF CLIPPER SYSTEMS AND SECONDARY SFC TROUGH THROUGH
LATE MONDAY AFTN/NIGHT. COULD SEE A QUICK 1-2" OF FLUFF WITH WAVE
GIVEN DEEP DGZ.
ATTENTION IN WAKE OF THIS WAVE WILL TURN TO BITTERLY COLD
TEMPERATURES (20 DEGREES BELOW NORMAL) TUE-WED AND POTENTIAL
SIGNIFICANT LAKE EFFECT SNOW EVENT MON NIGHT-TUE MORNING IN FAR NW
INDIANA/SW LOWER MI. SYNOPTIC FLOW LOCKS IN NORTHERLY DURING THIS
TIME WITH EXTREME OVER LAKE INSTABILITY AND FLOW DIRECTED PARALLEL
TO LONG AXIS OF LAKE LIKELY SUPPORTING STRONG CONVERGENCE. EXPECT
EXCELLENT SNOW GROWTH / RATIOS 30:1 OR SO / WITH OMEGA BULLSEYE IN
UPPER PORTION OF DGZ. MESOSCALE PROCESSES (MESOLOW DEVELOPMENT/LAND
BREEZE/AGGREGATE TROUGHING/ETC) WILL NO DOUBT MODULATE CONVECTIVE
LAYER TRAJECTORIES AND WHERE POTENTIAL INTENSE SINGLE BAND WILL SET
UP. WILL CONTINUE TO HIGHLIGHT THE THREAT FOR HEAVY LAKE EFFECT SNOW
IN THE HWO AND HOLD OFF ON ANY PERIOD 4 HEADLINES GIVEN NORMAL LAKE
EFFECT UNCERTAINTIES REGARDING PLACEMENT/TIMING...WITH BEST CHANCES
FOR WARNING LEVEL SNOWS/IMPACTS IN LA PORTE/STARKE/WESTERN ST JOE
IN/BERRIEN COUNTIES.
NEXT PV ANOMALY DIGS SOUTHEAST THROUGH THE LOWER GREAT LAKES WED-WED
EVE WITH NEXT OPPORTUNITY FOR WIDESPREAD LIGHT SNOW
ACCUMULATIONS...POSSIBLY FOLLOWED UP BY ANOTHER SIGNIFICANT LAKE
EFFECT/ENHANCED SNOW EVENT LATER WED NIGHT-THU. AND YEP...ANOTHER
SHORTWAVE AND REINFORCING SHOT OF ARCTIC AIR BY LATER FRI INTO SAT
PER LAST SEVERAL MODEL CYCLES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1236 PM EST SUN JAN 19 2014
LOW CLOUDS HAVE MOVED ON FOR THE TIME BEING AT BOTH TAF SITES.
CONCERNS EXIST WITH POTENTIAL FOR BRIEF EXCURSIONS INTO MVFR OR
POSSIBLY BRIEF IFR VSBYS FROM BLOWING SNOW THIS AFTERNOON AS
SUSTAINED WINDS OF 20 KTS OR MORE (GUSTS OVER 30 KTS) PERSIST AT
BOTH SITES. WILL MONITOR SITES NEXT HOUR OR 2 AND MAY NEED TO
AMEND TO COVER THIS...BUT THINK AMOUNT OF TIME THIS WILL OCCUR
ENOUGH TO IMPACT FLGT OPERATIONS WILL BE LESS THAN HALF.
MAINTAINED WIND SHEAR MENTION WITH VERY STRONG WINDS JUST OFF THE SFC.
FOCUS THE SHIFTS TO INCREASING LL MSTR MAINLY TONIGHT INTO MONDAY
AHEAD OF A FRONTAL BOUNDARY. MANY HI RES SOUNDINGS STILL SHOW A
NEARLY SATURATED LAYER THROUGH ABOUT 5000 FT. THIS SHOULD RESULT
IN RATHER WIDESPREAD STRATUS THROUGH THE NIGHT IN THE MVFR RANGE.
INCREASING LOW LEVEL LIFT WITH THIS INCREASED MSTR AND
TEMPERATURES UNDER 12 C ALOFT WILL CAUSE A FAVORABLE SETUP FOR
FREEZING DRIZZLE. GIVEN UPSTREAM TRENDS OF A LOT OF POCKETS OF
CLEAR AREAS WAS TEMPTED TO BACK OFF ON CIGS LATE AFTERNOON INTO
TOMORROW. HOWEVER...ENOUGH MSTR SHOULD STILL BE AROUND TO WARRANT
HOLDING ON BUT KEEP ANY FZDZ MENTION OUT AND ADRESS CLOSER WITH
00Z ISSUANCE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 AM EST MONDAY FOR LMZ043-046.
&&
$$
UPDATE...FISHER
SYNOPSIS...T
SHORT TERM...T
LONG TERM...STEINWEDEL
AVIATION...FISHER
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AREA FORECAST DISCUSSION
NWS MARQUETTE MI
413 PM EST SUN JAN 19 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 412 PM EST SUN JAN 19 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PERSISTENT NW FLOW
ALF OVER THE GREAT LKS BTWN UPR TROF OVER EASTERN NAMERICA AND A RDG
NEAR THE PACIFIC COAST. COLD FNT ASSOCIATED WITH STRONG DISTURBANCE/
SFC LO PRES MOVING INTO WRN QUEBEC IS IN THE PROCESS OF PUSHING N-E
THRU UPR MI EARLY THIS AFTN ACCOMPANIED BY SOME GENERALLY LGT SN
MAINLY NEAR LK SUP. MUCH COLDER AIR WITH 12Z H85 TEMPS AS LO AS -27C
AT YPL IS FOLLOWING THIS FNT...AND SFC TEMPS ARE IN THE PROCESS OF
FALLING OVER THE NRN TIER. DESPITE THE INFLUX OF MUCH COLDER AIR...
THE COMBINATION OF DNVA AHEAD OF AN APRCHG SHRTWV RDG/LOWERING INVRN
BASE TOWARD 3K FT PER SHORT TERM FCST SDNGS AND ADVECTION OF DRIER
LLVL AIR OSBVD IN ONTARIO IS TENDING TO HAMPER THE INTENSITY OF LES
FOLLOWING THE FROPA. IN FACT...VSBL STLT IMAGERY IS SHOWING QUITE A
BIT OF CLRG OVER THE N HALF OF LK SUP. THERE IS ANOTHER SHRTWV NEAR
LK WINNIPEG THAT IS DIVING ESEWD TOWARD THE CWA. STLT IMAGERY DOES
SHOW SOME ENHANCED CLD IN THE DPVA/DEEP LYR QVECTOR CNVGC AHEAD OF
THIS FEATURE...BUT THE LLVL DRYING IN THE NNE FLOW TO THE S OF SFC
ARCTIC HI PRES CENTERED OVER NRN MANITOBA IS LIMITING SN COVERAGE/
INTENSITY. YET ANOTHER CLIPPER TYPE SHRTWV OVER ALBERTA IS MOVING
SEWD.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE LES/SN AMOUNTS/GOING
HEADLINES AND IMPACT OF CLIPPER SHRTWVS THAT WL BE DIVING SEWD THRU
THE UPR LKS.
TNGT...SFC COLD FNT NOW DROPPING SWD THRU UPR MI WL CLEAR MENOMINEE
BY 00Z MON. INFLUX OF COLD AIR IN THE LLVL NLY FLOW BEHIND THIS
FROPA THAT IS FCST TO DROP H85 TEMPS TO ARND -23C OR -24C OVER THE
NRN TIER BY 12Z MON WL GENERATE LES IN THE FAVORED SN BELTS.
ALTHOUGH LLVL DRYING/LO INVRN BASE WL HAVE A NEGATIVE IMPACT ON THE
INTENSITY OF THE SHSN IN THE SHORT TERM...ARRIVAL OF DPVA/DEEP LYR
QVECTOR CNVGC ASSOCIATED WITH PAIR OF UPSTREAM CLIPPER SHRTWVS IS
FCST TO SLOWLY RAISE FCST INVRN BASE AND BRING ABOUT SOME DEEPER
MOISTENING. THE RESULT SHOULD BE AN INCRS IN LES INTENSITY
ESPECIALLY E OF MQT...WHERE LONGER FETCH OVER ICE FREE WATER AND
SHARPER LLVL CNVGC OVER ALGER/NRN SCHOOLCRAFT COUNTIES ON WRN FLANK
OF LAND BREEZE FLOW OFF ONTARIO WL TEND TO PLAY A POSITIVE ROLE
DESPITE SOME SLOWLY SHIFTING LLVL WINDS ACCOMPANYING PASSAGE OF UPR
DISTURBANCE. GOING LES ADVY FOR THE ERN CWA SEEMS APPROPIATE. AWAY
FM MOISTENING ASSOCIATED WITH LK SUP...DYNAMIC SUPPORT FM CLIPPER
SHRTWV WL PRODUCE NOTHING MORE THAN ISOLD-SCT LGT SHSN WITH LLVL
DRYING OFFSETTING THE ACCOMPANYING UPWARD MOTION. NLY FLOW OFF LK
SUP/ABUNDANT CLD COVER WL TEND TO MODERATE MIN TEMPS DESPITE THE
ARRIVAL OF THE COLDER AIR.
MON...CLIPPER NOW OVER ALBERTA/ACCOMPANYING DPVA AND DEEP LYR
QVECTOR CNVGC IS PROGGED TO SLIDE SEWD ACRS THE UPR MIDWEST/UPR LKS
IN THE MRNG. THIS DISTURBANCE SHOULD MAINTAIN HIER INVRN BASE AND
PERSISTENT LES NEAR LK SUP AS H85 TEMPS FALL TO ARND -26C IN SLOWLY
SHIFTING LLVL NLY FLOW. BUT THE DIMINISHING DGZ DEPTH ACCOMPANYING
INFLUX OF EVEN COLDER AIR AS WELL AS SLOWLY SHIFTING LLVL WINDS WL
TEND TO LIMIT SN TOTALS. BUT WL CONTINUE CATEGORICAL POPS FOR LES IN
THE FAVORED SN BELTS E OF MQT. ALTHOUGH THERE COULD BE SOME FREQUENT
SHSN EARLY NEAR IWD CLOSER TO THE TRACK OF THIS SECOND CLIPPER...
WENT WITH NO MORE THAN LIKELY POPS OVER THE WRN SN BELTS CONSIDERING
WEAKER LLVL CNVGC/MORE ICE COVER. WITH THE ARRIVAL OF COLDER AIR AND
ABUNDANT CLD COVER IN GENERAL N FLOW OFF LK SUP...EXPECT LTL DIURNAL
TEMP RECOVERY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 412 PM EST SUN JAN 19 2014
MODELS ARE IN GOOD AGREEMENT THROUGH MID WEEK WITH DETAILS ON LES
AND A CLIPPER SYSTEM MOVING THROUGH ON WED.
STARTING 00Z TUE...THE CWA WILL BE BENEATH A BROAD UPPER
TROUGH...WITH A WEAK SHORTWAVE JUST N OF LAKE SUPERIOR. 850MB TEMPS
WILL START OUT AOB -25C. LOW LEVEL WINDS WILL BE OUT OF THE NNW AS
THE CWA IS BETWEEN A SFC TROUGH OVER THE ERN SEABOARD AND A 1040MB
HIGH CENTERED OVER ND. A TROUGH WILL BE DRAPED FROM THE SSE INTO ERN
LAKE SUPERIOR...PROMOTING CYCLONIC FLOW THERE...WHILE FLOW OVER FAR
WRN LAKE SUPERIOR WILL BE SLIGHTLY ANTICYCLONIC. LES WILL BE ONGOING
IN ALL NNW WIND SNOWBELT...BUT THE MOST INTENSE SNOW WILL BE
DOWNWIND OF ERN LAKE SUPERIOR AS CONDITIONS THERE WILL BE MORE
FAVORABLE FOR MODERATE TO LOCALLY HEAVY LES /INCLUDING INVERSION
TOPS AROUND 7KFT/. NOT MUCH CHANGES THROUGH THE REST OF MON
NIGHT...EXCEPT THAT THE SFC HIGH WILL SLIDE TO FAR SW MN...MAKING
FOR EVEN LESS FAVORABLE FLOW AND SUBSIDENCE OVER WRN LAKE
SUPERIOR...WHILE THE TROUGH OVER ERN LAKE SUPERIOR REMAINS. THE MOST
UNCERTAINTY WITH LOCAL EFFECTS IS WITH ICE COVERAGE OVER WRN LAKE
SUPERIOR THAT MAY CLOSE DOWN PORTIONS OF THE LAKE TO LES. THERE WAS
GOOD ICE COVERAGE OVER THE W WHEN LOOKING AT SATELLITE IMAGERY
YESTERDAY...BUT WITH STRONG SW WINDS LAST NIGHT TURNING MORE NWLY
TODAY...NOT SURE ABOUT THE COVERAGE AND LOCATION OF THAT ICE INTO
THE FUTURE. THE NIGHT SHIFT LAST NIGHT PUT UP AN ADVISORY FOR
ALGER...NRN SCHOOLCRAFT AND LUCE COUNTIES...WHICH STILL LOOKS GOOD
THROUGH MON NIGHT.
THEN FOR TUE...THE SFC HIGH CONTINUES TO MOVE SE AS THE SFC TROUGH
OVER THE ERN LAKE DIMINISHES. FLOW BECOME VERY ANTICYCLONIC OVER ALL
BUT EXTREME ERN LAKE SUPERIOR /WHERE IT WILL BE NEUTRAL/ BY 00Z WED.
850MB TEMPS ALSO INCREASE TO AROUND -20C UNDER THE SFC RIDGE TUE.
SHOULD SEE LES DIMINISH THROUGH THE DAY...ESPECIALLY OVER THE W AND
CENTRAL. EVEN WITH CONDITIONS BEING UNFAVORABLE FOR SIGNIFICANT LES
OVER CENTRAL AND WRN UPPER MI...AREAS DOWNWIND OF LAKE SUPERIOR
SHOULD CONTINUE TO SEE SNOW...WHICH WOULD MAINLY BE AREAS N OFF THE
PORCUPINE MOUNTAINS OVER THE NWRN CWA. EXTENDED PREVIOUSLY MENTIONED
HEADLINES THROUGH TUESDAY AS THE LAKE TROUGHING SHOULD STICK AROUND
OVER ERN LAKE SUPERIOR...HELPING TO CONTINUE LES THROUGH MUCH OF THE
DAY. TUE LOOKS TO BE THE COLDEST DAY OF THE WEEK WITH HIGHS IN THE
SINGLE DIGITS ABOVE ZERO IN MOST LOCATIONS.
A CLIPPER SYSTEM BEGINS TO IMPACT WEATHER OVER THE CWA STARTING TUE
NIGHT AS THE SHORTWAVE MOVES TO N OF LAKE SUPERIOR IN ONTARIO BY 12Z
WED...BRINGING A BROAD...WEAK SFC LOW TO THE AREA. THIS LOW LOOKS TO
BE ENHANCED BY LAKE AGGREGATE AS A MESO LOW MAY FORM OVER LAKE
SUPERIOR...BUT TO WHAT MAGNITUDE AND EXACTLY WHERE IS UNCERTAIN. THE
12Z/19 NAM...00Z/19 GLOBAL GEM AND TO SOME EXTENT THE 00Z/19 ECMWF
FAVOR THE MESO LOW TO MOVE OVER E CENTRAL LAKE SUPERIOR...MOVING
INTO UPPER MI SOMEWHERE E OF MARQUETTE WED EVENING. THIS PATH IS
TYPICALLY WITH THIS TYPE OF PATTERN...BUT THE EXACTLY WHERE THAT LOW
MOVES WILL DETERMINE WHERE THE STRONGEST SNOW AND WIND WILL FOCUS.
THIS COULD BE QUITE AN INTERESTING EVENT OVER A SHORT PERIOD OF TIME
AS THE MESO LOW WILL VERY QUICKLY SHIFT SE AS IT MOVES OFF OF LAKE
SUPERIOR...WHILE AT THE SAME TIME A 1050MB HIGH MOVES ACROSS THE
DAKOTAS INTO THE CENTRAL PLAINS...SHUNTING A 1030MB SFC RIDGE INTO
THE CWA LATE WED NIGHT INTO THU. MOST OF THE CWA WILL SEE GUSTY
WINDS AS A RESULT OF THE PRESSURE GRADIENT AND PRESSURE RISE...BUT
THE AREA OF MOST CONCERN IS ON THE W SIDE OF THE TRACK OF THE
POSSIBLE MESO LOW...WHERE BLIZZARD LIKE CONDITIONS MAY BE POSSIBLE.
WITH LOW LEVEL WINDS OUT OF THE NNE FOR ABOUT 6 HOURS ALONG AND
BEHIND THE MESO LOW AND FROM JUST AHEAD TO JUST BEHIND THE
SHORTWAVE...NCENTRAL UPPER MI WOULD BE FAVORED FOR UPSLOPE AND LAKE
ENHANCEMENT THAT MAY MAKE FOR VERY TREACHEROUS CONDITIONS SOMEWHERE
IN THE LATE WED AFTERNOON THROUGH WED EVENING TIME FRAME.
AGAIN...THESE ARE PRETTY LOCALIZED CONDITIONS WHICH WILL BE
DIFFICULT TO EXACTLY PREDICT EVENT A DAY OUT...BUT THE CHANCE OF
THIS HAPPENING SOMEWHERE ACROSS NCENTRAL UPPER MI IS PRETTY GOOD
GIVEN THE OVERALL PATTERN. OUTSIDE OF THE IMMEDIATE AREA AFFECTED BY
THE MESO LOW...THE REST OF NWRN UPPER MI LOOKS FAVORED FOR A GOOD
BURST OF SNOW AS THE SHORTWAVE PASSES.
EXPECT LES WED NIGHT AS LOW LEVEL WINDS SHIFT FROM NLY TO NWLY WITH
-25C 850MB TEMPS...BUT WITH THE SFC RIDGE PASSING OVERHEAD ON
THU...THE LES SHOULD QUICKLY WEAKEN THU MORNING/EARLY AFTERNOON.
HOWEVER...BY LATER THU...WINDS WILL BECOME MORE CYCLONIC AHEAD OF
ANOTHER CLIPPER THAT WILL STAY MAINLY NE OF THE CWA. THE MORE
FAVORABLE CURVATURE TO THE FLOW WILL FAVORED THE KEWEENAW FOR LES AS
STRONG WINDS WILL BE OUT OF THE WSW THROUGH 06Z FRI...VEERING OUT OF
THE WNW BEHIND THE CLIPPER BY 18Z FRI. 850MB TEMPS LATE THU THROUGH
FRI WILL BE IN THE -15C TO -20C RANGE...WHICH WILL PUT MORE OF THE
THERMAL PROFILE IN THE DGZ...BUT INVERSION HEIGHTS LOOK TO ONLY BE
4-5KFT.
UNCERTAINTY INCREASES CONSIDERABLY FOR THE WEEKEND AS MODELS HAVE
NOT SHOWN GOOD CONTINUITY WITH THE PLACEMENT OF FEATURES THIS FAR
OUT. ONE TREND THAT CAN BE NOTED IS THAT THE COLDER AIR /850MB TEMPS
BELOW -30C/ SHOWN IN PREVIOUS SEVERAL MODEL RUNS MOVING OVER THE CWA
IS NOW BEING SHOWS AS MORE OF A GLANCING BLOW...WITH THE COLDEST AIR
TO THE NE. THIS COULD CHANGE...BUT AT LEAST IT IS A NOTABLE TREND
FOR NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1224 PM EST SUN JAN 19 2014
A COLD NNE FLOW OF ARCTIC AIR OFF LK SUP WL BRING LK EFFECT -SHSN TO
THE TAF SITES THIS PERIOD. BUT A FEED OF LLVL DRY AIR ASSOCIATED
WITH COLD HI PRES OVER SCENTRAL CANADA WL TEND TO LIMIT THE
INTENSITY OF THIS PCPN. SO MVFR CONDITIONS SHOULD PREDOMINATE. THE
BEST CHC FOR IFR CONDITIONS WL BE AT IWD ON MON MRNG...WHEN A
PASSING DISTURBANCE IN THE PRESENCE OF A FVRBL NNE FLOW AND DEEPER
MSTR MAY ENHANCE THE SHSN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 412 PM EST SUN JAN 19 2014
EXPECT N TO NW WINDS UP TO 25 TO 30 KTS TONIGHT AND MON E OF ARCTIC
HI PRES IN SCENTRAL CANADA. WITH A VERY COLD AIRMASS MOVING INTO THE
UPPER LAKES...THE RESULTING WAVE ACTION WILL CAUSE WIDESPREAD HEAVY
FREEZING SPRAY.
HEAVY FREEZING SPRAY WILL CONTINUE ACROSS ALL OF LAKE SUPERIOR
THROUGH AT LEAST TUESDAY IF NOT LONGER AS AREA IS ENTRENCHED IN COLD
AIR. NEXT GALE EVENTS LOOK TO BE ACROSS CENTRAL AND EASTERN LAKE
SUPERIOR LATE WEDNESDAY INTO WEDNESDAY NIGHT AND ANOTHER EVENT FOR
THURSDAY NIGHT ACROSS THE SAME AREA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST TUESDAY FOR MIZ006-007-
085.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST TUESDAY FOR
LSZ249>251-266-267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST TUESDAY FOR LSZ244-
245-248-264-265.
HEAVY FREEZING SPRAY WARNING FROM 7 AM MONDAY TO 7 AM EST
TUESDAY FOR LSZ243-263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KC
MARINE...KC/TITUS
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
254 PM MST Sun Jan 19 2014
.DISCUSSION...
Tonight through Tuesday...Overall pattern remains unchanged with a
strong upper ridge over the west coast and dry northwest flow
aloft. Models move a weak short wave embedded within the northwest
flow aloft through the area late this evening. Surface winds will
shift to the north for a few hours. The RUC and the European
models develop light qpf near the Little Belts as a result of this
weak upslope flow. HRRR analysis also develops qpf in this area
for a few hours late this evening. Have gone with low pops to
support this possibility. The surface gradient is not as tight on
Monday allowing for lighter winds. Monday and Tuesday will
continue dry with a northerly flow aloft. Temperatures will remain
above seasonal averages.
Tuesday night through Sunday...The main change in the extended
period was to increase the chances for rain/snow Wednesday into
Wednesday night...as both the EC/GFS continue to show an upper
level disturbance moving southward through the region. There looks
to be a bit more moisture with this disturbance...thus pops have
been increased...especially in the mountains around Kings Hill.
Snow accumulations still look to be on the low side...with most
lower elevation locations only seeing around 1 inch of
snowfall...and about 2 to 3 inches in the mountains. After this
disturbance moves through little to no precipitation is expected
from Thursday through Sunday. Temperatures will cool a bit
Wednesday as the disturbance moves through the region...with high
temperatures likely in the morning and then falling in the
afternoon. It will be cold Wednesday night as skies clear out a
bit...and with the possible fresh snow cover...temperatures will
fall rather quickly early Thursday morning. Otherwise...expect
afternoon temperatures to generally be about 5 to 10 degrees above
normal starting as early as Thursday afternoon and then continuing
into next weekend. Brusda
&&
.AVIATION...
UPDATED 1815Z.
VFR conditions will prevail at all sites through the TAF period. Mid
level clouds will spread south across the area through the
day...with clearing expected overnight. Breezy conditions can be
expected through the afternoon hours across North Central and
Central Montana. Suk
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 26 46 29 51 / 0 0 0 0
CTB 20 44 24 47 / 0 0 0 0
HLN 23 43 24 46 / 0 0 0 0
BZN 20 39 19 42 / 0 0 0 0
WEY 7 32 8 33 / 0 0 0 0
DLN 22 41 23 45 / 0 0 0 0
HVR 22 35 20 40 / 0 0 0 0
LWT 23 39 25 44 / 0 0 0 10
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1159 AM CST SUN JAN 19 2014
.UPDATE...
RECORD OR NEAR RECORD TEMPERATURES EXPECTED TODAY. NUDGED
TEMPERATURES UPWARD WITH BETTER MIXING AND TWEAKED DEWPOINTS.
&&
.DISCUSSION...
THE LATEST RAP IS SHOWING SOME BETTER MIXING POTENTIAL COMPARED TO
THE NAM/GFS. TEMPERATURES ALREADY IN THE 50S AND SHOULD CONTINUE
TO WARM TO RECORD OR NEAR RECORD LEVELS THIS AFTERNOON. MORNING
SOUNDINGS ARE PRETTY DRY AND THIS ALONG WITH LACK OF SNOWCOVER
SHOULD HELP WARM TEMPERATURES. DO HAVE SOME INCREASING CIRRUS
TODAY AHEAD OF THE NEXT WEATHER SYSTEM. RECORDS FOR TODAY ARE 60
AT OMAHA/65 AT LINCOLN AND 66 AT NORFOLK.
&&
.AVIATION...
18Z TAFS FOR KOMA...KLNK...AND KOFK.
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF CYCLE WITH INCREASING
CIRRUS THIS AFTERNOON. MAY SEE SOME MID CLOUD CIGS MONDAY MORNING
ASSOCIATED WITH THE SHORTWAVE PASSING TO OUR AND PUSH OF COLD AIR
INTO THE AREA. WEST AND NORTHWEST WINDS TODAY 10 TO 15KTS WITH
STRONGER GUSTS AT KOFK THIS AFTERNOON...DECREASING TO BELOW 10KTS
TONIGHT AND THEN AGAIN INCREASING TO 15 TO 20KTS WITH HIGHER GUSTS
AFTER 15Z MONDAY.
&&
PREV DISCUSSION... /ISSUED 325 AM CST SUN JAN 19 2014/
DISCUSSION...
ALL FACTORS CONTINUE TO POINT TO A VERY WARM MID WINTER DAY ACROSS
THE FORECAST AREA. THE 08Z SURFACE ANALYSIS INDICATED THE HIGH
PRESSURE RIDGE ASSOCIATED WITH THE SHORTWAVE FROM SATURDAY HAS
BUILT INTO THE SOUTHERN PLAINS AND THE LOW LEVEL FLOW ACROSS
NEBRASKA/IOWA HAS TURNED TO THE SOUTHWEST. AS A SHORTWAVE RIDGE
CROSSES THE NORTHERN PLAINS TODAY WE SHOULD SEE PLENTY OF SUN TO
HELP WITH THE MIXING POTENTIAL. WE CURRENTLY FEEL THE MODELS ARE
STILL STRUGGLING TO MIX SUFFICIENTLY GIVEN THE ABOVE FACTORS AND
WE HAVE INCREASED THE HIGHS A CAT OR TWO MOST AREAS TODAY. WE ARE
STILL LIKELY TO FALL SHORT OF ANY RECORDS...BUT WE WILL LIKELY SEE
THE 60 DEGREE MARK MAKE IT INTO THE WESTERN PART OF THE OMAHA
METRO AND POINTS TO THE WEST. LOCATIONS ALONG THE RIVER AND EAST
WILL LIKELY HOLD IN THE MID AND UPPER 50S TODAY.
EARLY MORNING WATER VAPOR IMAGERY INDICATES THAT THE NEXT
SHORTWAVE TROUGH IS CURRENTLY MOVING THROUGH NORTHERN ALBERTA.
THIS WILL TRACK INTO THE GREAT LAKES ON MONDAY AND ALLOW FOR A
BACK DOOR COLD FRONT TO PUSH SWWD INTO THE FA BY LATE AFTERNOON.
MOST MODELS /ESPECIALLY THE GEM AND EC/ INDICATE A SECONDARY WEAK
SHORTWAVE TROUGH SLIDING ALONG THIS TIGHT THERMAL GRADIENT DURING
THE AFTERNOON/EVENING ENHANCING THE ALREADY STRONG LOW LEVEL
FRONTOGENESIS. EVEN IF THE WEAKER NAM/GFS SOLUTIONS PROVE BETTER
THE LOW LEVEL FRONTOGENESIS AND SATURATION IN THE DENDRITIC LAYER
SHOULD LEAD TO A BAND OF LIGHT SNOW MOVING INTO THE NORTHERN FA
DURING THE LATE AFTERNOON ON MONDAY AND THEN CONTINUING SWWD
MONDAY EVENING. WE HAVE INCREASED POPS INTO THE LIKELY CAT FOR
LATE MON AFTERNOON IN THE NORTH AND THEN EXPANDED THOSE SOUTHWEST
DURING MONDAY EVENING. WE ARE NOT EXPECTING MUCH IN THE WAY OF
ACCUMULATIONS...MAYBE UP TO A HALF INCH IN THE NORTH...BUT SOME
-SN APPEARS LIKELY. SEASONABLY COLD AIR FOLLOWS THIS SYSTEM FOR
TUESDAY AND WE HAVE LOWERED HIGHS OVER THE EASTERN FA WHERE MIXING
IS EXPECTED TO BE LIMITED ALONG THE SURFACE RIDGE AXIS.
A BRIEF WARMUP IS IN STORE FOR TUE NIGHT INTO WED BEFORE THE NEXT
POLAR COLD FRONT MOVES THROUGH THE FA. THIS FRONT DOESN`T APPEAR
TO HAVE THE MOISTURE THAT THE MONDAY FRONT WILL HAVE...BUT THE AIR
BEHIND THIS FRONT APPEARS JUST AS COLD IF NOT COLDER FOR WED NIGHT
AND THURSDAY WITH LOCATIONS IN THE NORTHERN FA FALLING BELOW ZERO.
AS HAS BEEN THE PATTERN THIS WINTER THE COLD AIR DOESN`T HANG
AROUND LONG WITH WESTERLY FLOW DEVELOPING BY NEXT FRI AND SAT
ALLOWING FOR WARMER AIR TO FLOOD INTO THE FA. WITH AN EXPECTED
CONTINUED LACK OF SNOW COVER AT THAT TIME GUIDANCE APPEARS TOO
COOL FOR HIGHS NEXT FRI/SAT AND WE HAVE INCREASED HIGHS INTO THE
40S.
BOUSTEAD
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
205 PM EST SUN JAN 19 2014
.SYNOPSIS...
A DISTURBANCE IN THE JET STREAM WINDS ALOFT AND AN ARCTIC COLD
FRONT WILL PRODUCE PERIODS OF SNOW SHOWERS ACROSS THE NORTH
COUNTRY TODAY AND TONIGHT. OVERALL...SNOW ACCUMULATIONS WILL BE
LIGHT WITH 1 TO 3 INCHES IN GENERAL EXPECTED. BEHIND THE
FRONT...A RETURN OF MUCH COLDER AND DRIER CONDITIONS IS EXPECTED
FOR THE UPCOMING WEEK...WITH HIGHS ONLY IN THE SINGLE DIGITS
ABOVE ZERO AND LOWS IN THE SINGLE DIGITS TO TEENS BELOW FOR
MONDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1246 PM EST SUNDAY...BOTH COVERAGE AND INTENSITY OF SNOW
SHOWERS HAVE DIMINISHED ACROSS FORECAST AREA WITH DEPARTURE OF
SHORTWAVE TROUGH. LITTLE ADDITIONAL ACCUMULATION EXPECTED THIS
AFTERNOON IN MOST AREAS WITH ONLY CHANCE POPS PREFERRED FOR MOST
OF VERMONT AND CHAMPLAIN VALLEY. PERSISTENT SOUTHWEST FLOW WILL
ALLOW FOR MORE SNOW SHOWERS ACROSS SAINT LAWRENCE VALLEY AND
ADIRONDACKS THIS AFTERNOON HOWEVER. ACTIVITY WILL THEN INCREASE
ACROSS THE REST OF THE REST OF THE FORECAST AREA ONCE AGAIN THIS
EVENING WITH APPROACH OF ARCTIC FRONT. MAX TEMPS STILL EXPECTED TO
BE IN THE UPPER 20S AND LOWER 30S.
EARLIER DISCUSSION...
VERY LITTLE OVERALL CHANGE FROM PREVIOUS FORECAST THINKING FOR
TODAY AS THE ATMOSPHERE IS BEHAVING MUCH LIKE WE EXPECTED. LATEST
GUIDANCE CONTINUES TO SLOW DOWN THE APPROACH OF AN ARCTIC FRONT
WHICH NOW LOOKS TO AFFECT THE NORTH COUNTRY TOWARD THIS EVENING
AND TONIGHT...SO FOR TODAY WE`LL BE DEALING WITH A POTENT
SHORTWAVE TROUGH CURRENTLY OVER THE OHIO RIVER VALLEY WHICH WILL
SHIFT EASTWARD THROUGH THE MID-ATLANTIC STATES. LATEST WV IMAGERY
CONTINUES TO SUPPORT THE IDEA THAT THE BEST PVA SLIDES TO OUR
SOUTH TODAY...BUT 13KM RAP CONTINUES TO SHOW A PIECE OF ENERGY
BREAKING OFF AND TRACKING NORTHEAST THROUGH THE CWA THIS MORNING.
WITH THE EXCEPTIONAL PERFORMANCE OF THE RAP OVER THE LAST FEW DAYS
IT`S HARD TO IGNORE IT...AND OVERALL IT MAKES SENSE BASED ON THE
UPPER FLOW TRENDING SOUTHWESTERLY. THAT SAID...WE`LL SEE PERIODS
OF SNOW SHOWERS THIS MORNING THROUGH ABOUT MID-DAY...WITH A BREAK
IN THE ACTION THIS AFTERNOON AS THE SHORTWAVE ENERGY SHIFTS
NORTHEAST OF THE REGION AND WE AWAKE ANOTHER ROUND OF SNOW SHOWERS
ASSOCIATED WITH THE ARCTIC FRONT. OVERALL QPF WILL BE VERY LIGHT
WITH JUST A FEW HUNDREDTHS OF LIQUID EXPECTED...AMOUNTING TO JUST
A DUSTING TO MAYBE 2 INCHES THROUGH THE DAY. TEMPS WILL BE THE
LAST ABOVE NORMALS WE`LL SEE FOR AWHILE AND GENERALLY IN THE 20S
TO A FEW LOW 30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
AS OF 340 AM EST SUNDAY...FOR TONIGHT INTO MONDAY FOCUS TURNS
TOWARDS AN ARCTIC BOUNDARY WHICH WILL SWING NORTHWEST TO
SOUTHEAST THROUGH THE CWA. AS MENTIONED ABOVE...LATEST GUIDANCE
CONTINUES TO SLOW THE PROGRESSION OF SAID FEATURE WITH SOME
RESIDUAL LAKE ENHANCED SNOW SHOWERS NOW POSSIBLY LINGERING
THROUGH MID-DAY MONDAY ACROSS CENTRAL AND SOUTHERN AREAS.
OVERALL...FRONT SHOULD MOVE INTO NORTHWESTERN PORTIONS OF THE
REGION LATE THIS EVENING WITH LOCAL WRF`S AND RAP CONTINUING TO
SHOW FAVORABLE CONDITIONS FOR SNOW SQUALLS. THINKING ANOTHER
DUSTING TO 2 INCHES WILL BE POSSIBLE TONIGHT...WITH MUCH OF THAT
LIKELY OCCURRING IN A VERY SHORT PERIOD OF TIME. COME MONDAY
MORNING FRONT WILL BE SOMEWHERE ACROSS CENTRAL AND SOUTHERN
VERMONT WITH SOME LINGERING LAKE ENHANCED SHOWERS SHOWERS AROUND
ESPECIALLY ACROSS THE HIGHER TERRAIN...BUT AS DRIER AIR MOVES IN
UNDER STRONG CAA ON NORTHWEST FLOW SNOW SHOULD TAPER OFF BY THE
AFTERNOON HOURS. DAYTIME HIGHS IN THE TEENS WILL LIKELY BE
REACHED DURING THE MORNING HOURS...SLOWLY FALLING THROUGH THE DAY
WITH THE EXCEPTION BEING THE FAR SOUTHEAST CORNER OF VT WHERE
HIGHS WILL BE IN THE MID 20S AHEAD OF THE FRONT.
FOR MONDAY NIGHT AND TUESDAY SURFACE HIGH PRESSURE BUILDS INTO
THE REGION WITH CLEARING SKIES AND BONE CHILLING TEMPERATURES
EXPECTED. MONDAY NIGHT LOWS WILL FALL INTO THE SINGLE DIGIT TO
TEENS BELOW ZERO...AND WITH MODERATE GRADIENT FLOW REMAINING
BETWEEN THE BUILDING HIGH AND DEPARTING LOW WE`LL LIKELY BE
LOOKING AT SOME WIND CHILL ADVISORIES FOR PORTIONS OF NORTHERN
NEW YORK AND NORTHEAST VERMONT. WINDS WILL SLACKEN OFF FOR TUESDAY
WITH PARTLY SUNNY SKIES AND HIGHS ONLY IN THE THE SINGLE DIGITS
BELOW TO 10 ABOVE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 205 PM EST SUNDAY...MODELS SHOWING GOOD RUN TO RUN
CONSISTENCY FOR AN OVERALL QUIET PERIOD THRU THE END OF THE WORK
WEEK. NEXT CHANCE FOR WIDESPREAD PRECIP WILL BE OVER THE WEEKEND.
UPPER LVL TROUGH OVER THE NORTHEAST KEEPS SOME CLOUDS AROUND AS
RIDGING BUILDS JUST TO THE WEST. A WEAKENING SHORTWAVE WILL MOVE
TO THE SOUTH OF THE FA ON THURSDAY...BRINGING ONLY SLGT CHC FOR
SNOW SHOWERS TO SRN VT. COLD AIR CONTINUES WITH 850MB TEMPS
AROUND -24C AND 925MB TEMPS OF -20C TO -26C. AT THE SFC THIS WILL
MEAN WEDNESDAY AND THURSDAY MAX TEMPS IN THE SINGLE DIGITS...WITH
MIN TEMPS WEDNESDAY NIGHT AND THURSDAY NIGHT BELOW ZERO.
ON FRIDAY...SFC RIDGE AXIS SHIFTS TO THE EAST...PUTTING THE NORTH
COUNTRY IN MODERATING SW FLOW...AHEAD OF APPROACHING CLOSED LOW
PRESSURE SYSTEM. WARMING TREND WILL BE NOTICEABLE AT THE SFC WITH
FRIDAY MAX TEMPS IN THE TEENS AND FRIDAY NGT MIN TEMPS ABOVE
ZERO.
GFS STARTS TO BRING SNOW FROM AFOREMENTIONED SYSTEM INTO THE SLV
LATE FRIDAY/FRIDAY NIGHT. ECMWF A LITTLE SLOWER WITH RIDGE SLOW
TO WEAKEN AND SHIFT SE. OVERALL INCREASING THREAT OF SNOW SHOWERS
FRIDAY NGT INTO SATURDAY...WITH BULK OF PRECIP ASSOCIATED WITH
COLD FRONT MOVING THROUGH THE REGION ON SATURDAY INTO SATURDAY
NIGHT. WARM TEMPS NEAR NORMAL ON SATURDAY WILL BE SHORT LIVED
WITH THE COLD FRONTAL PASSAGE BRINGING SUNDAY MAX TEMPS INTO THE
TEENS TO L20S.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
THROUGH 18Z MONDAY...VFR AND MVFR CONDITIONS CONTINUE THIS AFTN
AND EARLY EVENING. LGT SNOW SHOWERS CONTINUE TO AFFECT THE NORTH
COUNTRY...SO OVERALL VFR CONDITIONS WILL SEE MVFR CONDITIONS
WITHIN SNOW SHOWERS AHEAD OF COLD FRONT APPROACHING FROM THE NW.
MOST AREAS WILL SEE A BREAK IN SNOW SHOWERS FROM 19Z TO AT LEAST
00Z. SNOW SHOWERS WILL INCREASE NEAR 03Z IN THE SLV AS THE FRONT
APPROACHES...PRODUCING SNOW SQUALLS WITH IFR TO LIFR CONDITIONS.
DIFFICULT TO PINPT TIMING OF THIS FRONT...AS MODEL TRENDS
CONTINUE TO SLOW ITS PROGRESSION. AT THIS PT...EXPECT FRONT AND
IFR/LIFR CONDITIONS TO AFFECT KMSS BTWN 03Z-08Z...CPV 04Z-
10Z...KMPV 06Z- 11Z AND KRUT AFTER 08Z BUT WEAKENING. KSLK MAY
SEE IFR IN SNOW SHOWERS AHEAD OF THE FRONT WITHIN THE UPSLOPE SW
FLOW STARTING 21Z...WITH THE FRONT REACHING THE AREA AROUND 05Z-
10Z.
BEHIND THE FRONT...CONDITIONS WILL IMPROVE TO VFR AS SNOW SHOWERS
TAPER OFF. PSBL EXCEPTION AT KSLK IN CONTINUED UPSLOPE.
WINDS WILL BE GUSTY FROM THE S-SW AT 10-20KTS WITH GUSTS OF
20-30KTS...PSBLY HIGHER IN THE SLV. BEHIND THE FRONT WINDS WILL
GRADUALLY SUBSIDE...WITH GUSTS DIMINISHING AFTER DAYBREAK AS
WINDS SHIFT TO THE NW.
OUTLOOK 18Z MONDAY THROUGH FRIDAY...
18Z MONDAY THROUGH 21Z MONDAY...TRENDING VFR THOUGH SOME
LINGERING MVFR/IFR SHSN POSSIBLE AS ARCTIC FRONT CLEARS SOUTH OF
THE REGION.
21Z MONDAY ONWARD...MAINLY VFR WITH HIGH PRESSURE AND VERY COLD
TEMPERATURES.
&&
.EQUIPMENT...
AS OF 340 AM EST SUNDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM BUT IT WILL
LIKELY BE OUT OF SERVICE THROUGH AT LEAST TUESDAY JANUARY 21.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...RJS/LAHIFF
SHORT TERM...LAHIFF
LONG TERM...KGM
AVIATION...KGM
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1251 PM EST SUN JAN 19 2014
.SYNOPSIS...
A DISTURBANCE IN THE JET STREAM WINDS ALOFT AND AN ARCTIC COLD
FRONT WILL PRODUCE PERIODS OF SNOW SHOWERS ACROSS THE NORTH
COUNTRY TODAY AND TONIGHT. OVERALL...SNOW ACCUMULATIONS WILL BE
LIGHT WITH 1 TO 3 INCHES IN GENERAL EXPECTED. BEHIND THE
FRONT...A RETURN OF MUCH COLDER AND DRIER CONDITIONS IS EXPECTED
FOR THE UPCOMING WEEK...WITH HIGHS ONLY IN THE SINGLE DIGITS
ABOVE ZERO AND LOWS IN THE SINGLE DIGITS TO TEENS BELOW FOR
MONDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1246 PM EST SUNDAY...BOTH COVERAGE AND INTENSITY OF SNOW
SHOWERS HAVE DIMINISHED ACROSS FORECAST AREA WITH DEPARTURE OF
SHORTWAVE TROUGH. LITTLE ADDITIONAL ACCUMULATION EXPECTED THIS
AFTERNOON IN MOST AREAS WITH ONLY CHANCE POPS PREFERRED FOR MOST
OF VERMONT AND CHAMPLAIN VALLEY. PERSISTENT SOUTHWEST FLOW WILL
ALLOW FOR MORE SNOW SHOWERS ACROSS SAINT LAWRENCE VALLEY AND
ADIRONDACKS THIS AFTERNOON HOWEVER. ACTIVITY WILL THEN INCREASE
ACROSS THE REST OF THE REST OF THE FORECAST AREA ONCE AGAIN THIS
EVENING WITH APPROACH OF ARCTIC FRONT. MAX TEMPS STILL EXPECTED TO
BE IN THE UPPER 20S AND LOWER 30S.
EARLIER DISCUSSION...
VERY LITTLE OVERALL CHANGE FROM PREVIOUS FORECAST THINKING FOR
TODAY AS THE ATMOSPHERE IS BEHAVING MUCH LIKE WE EXPECTED. LATEST
GUIDANCE CONTINUES TO SLOW DOWN THE APPROACH OF AN ARCTIC FRONT
WHICH NOW LOOKS TO AFFECT THE NORTH COUNTRY TOWARD THIS EVENING
AND TONIGHT...SO FOR TODAY WE`LL BE DEALING WITH A POTENT
SHORTWAVE TROUGH CURRENTLY OVER THE OHIO RIVER VALLEY WHICH WILL
SHIFT EASTWARD THROUGH THE MID-ATLANTIC STATES. LATEST WV IMAGERY
CONTINUES TO SUPPORT THE IDEA THAT THE BEST PVA SLIDES TO OUR
SOUTH TODAY...BUT 13KM RAP CONTINUES TO SHOW A PIECE OF ENERGY
BREAKING OFF AND TRACKING NORTHEAST THROUGH THE CWA THIS MORNING.
WITH THE EXCEPTIONAL PERFORMANCE OF THE RAP OVER THE LAST FEW DAYS
IT`S HARD TO IGNORE IT...AND OVERALL IT MAKES SENSE BASED ON THE
UPPER FLOW TRENDING SOUTHWESTERLY. THAT SAID...WE`LL SEE PERIODS
OF SNOW SHOWERS THIS MORNING THROUGH ABOUT MID-DAY...WITH A BREAK
IN THE ACTION THIS AFTERNOON AS THE SHORTWAVE ENERGY SHIFTS
NORTHEAST OF THE REGION AND WE AWAKE ANOTHER ROUND OF SNOW SHOWERS
ASSOCIATED WITH THE ARCTIC FRONT. OVERALL QPF WILL BE VERY LIGHT
WITH JUST A FEW HUNDREDTHS OF LIQUID EXPECTED...AMOUNTING TO JUST
A DUSTING TO MAYBE 2 INCHES THROUGH THE DAY. TEMPS WILL BE THE
LAST ABOVE NORMALS WE`LL SEE FOR AWHILE AND GENERALLY IN THE 20S
TO A FEW LOW 30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
AS OF 340 AM EST SUNDAY...FOR TONIGHT INTO MONDAY FOCUS TURNS
TOWARDS AN ARCTIC BOUNDARY WHICH WILL SWING NORTHWEST TO
SOUTHEAST THROUGH THE CWA. AS MENTIONED ABOVE...LATEST GUIDANCE
CONTINUES TO SLOW THE PROGRESSION OF SAID FEATURE WITH SOME
RESIDUAL LAKE ENHANCED SNOW SHOWERS NOW POSSIBLY LINGERING
THROUGH MID-DAY MONDAY ACROSS CENTRAL AND SOUTHERN AREAS.
OVERALL...FRONT SHOULD MOVE INTO NORTHWESTERN PORTIONS OF THE
REGION LATE THIS EVENING WITH LOCAL WRF`S AND RAP CONTINUING TO
SHOW FAVORABLE CONDITIONS FOR SNOW SQUALLS. THINKING ANOTHER
DUSTING TO 2 INCHES WILL BE POSSIBLE TONIGHT...WITH MUCH OF THAT
LIKELY OCCURRING IN A VERY SHORT PERIOD OF TIME. COME MONDAY
MORNING FRONT WILL BE SOMEWHERE ACROSS CENTRAL AND SOUTHERN
VERMONT WITH SOME LINGERING LAKE ENHANCED SHOWERS SHOWERS AROUND
ESPECIALLY ACROSS THE HIGHER TERRAIN...BUT AS DRIER AIR MOVES IN
UNDER STRONG CAA ON NORTHWEST FLOW SNOW SHOULD TAPER OFF BY THE
AFTERNOON HOURS. DAYTIME HIGHS IN THE TEENS WILL LIKELY BE
REACHED DURING THE MORNING HOURS...SLOWLY FALLING THROUGH THE DAY
WITH THE EXCEPTION BEING THE FAR SOUTHEAST CORNER OF VT WHERE
HIGHS WILL BE IN THE MID 20S AHEAD OF THE FRONT.
FOR MONDAY NIGHT AND TUESDAY SURFACE HIGH PRESSURE BUILDS INTO
THE REGION WITH CLEARING SKIES AND BONE CHILLING TEMPERATURES
EXPECTED. MONDAY NIGHT LOWS WILL FALL INTO THE SINGLE DIGIT TO
TEENS BELOW ZERO...AND WITH MODERATE GRADIENT FLOW REMAINING
BETWEEN THE BUILDING HIGH AND DEPARTING LOW WE`LL LIKELY BE
LOOKING AT SOME WIND CHILL ADVISORIES FOR PORTIONS OF NORTHERN
NEW YORK AND NORTHEAST VERMONT. WINDS WILL SLACKEN OFF FOR TUESDAY
WITH PARTLY SUNNY SKIES AND HIGHS ONLY IN THE THE SINGLE DIGITS
BELOW TO 10 ABOVE.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 212 AM EST SUNDAY...QUIET...COLD AND MAINLY DRY PATTERN WILL
BECOME LOCKED IN ACROSS THE EASTERN HALF OF THE U.S. DURING THE
MID TO LATE WEEK TIME FRAME AND LIKELY BEYOND AS ARCTIC AIR HAS A
DIRECT PATHWAY INTO OUR REGION. THIS IS A VERY STABLE
PATTERN...AND UNTIL MORE ORGANIZED ENERGY CAN CRASH EASTWARD
THROUGH THE HIGH-AMPLITUDE WESTERN CONUS RIDGE...THE CURRENT HIGH
AMPLITUDE PATTERN SHOULD MORE OR LESS HOLD IN PLACE FOR THE NEXT
10 DAYS. IN TERMS OF SENSIBLE WEATHER...TEMPERATURES WILL REMAIN
WELL BELOW NORMAL WEDNESDAY INTO FRIDAY THOUGH WITH SOME SLIGHT
AIRMASS MODERATION BY ABOUT 5 DEGREES EACH DAY. OVERNIGHT LOWS
CONSISTENTLY BELOW ZERO WITH COLDEST NIGHT OCCURRING TUESDAY NIGHT
WHEN WIDESPREAD 10 TO 20 BELOW READINGS LIKELY. A WEAK CLIPPER LOW
PASSING SOUTH OF THE AREA MAY SPREAD SOME CLOUDINESS AND PERHAPS A
BRIEF PERIOD OF FLURRIES/VERY LIGHT SNOW TO OUR SOUTHERN COUNTIES
ON THURSDAY...OTHERWISE MAINLY DRY WEATHER IS EXPECTED THROUGH
FRIDAY.
BY FRIDAY NIGHT SOUTHERLY FLOW RETURNS AS SFC RIDGE DEPARTS EAST
ALLOWING TEMPERATURES TO CLIMB SLOWLY...REACHING NEAR MID-WINTER
SEASONAL NORMS FOR ONE BRIEF DAY ON SATURDAY. ADDITIONAL NORTHERN
STREAM ENERGY ACCOMPANIED BY YET ANOTHER IMPRESSIVE ARCTIC BOUNDARY
TO THEN SWEEP INTO THE REGION BY LATER SATURDAY/SATURDAY NIGHT WHERE
I`LL MAINTAIN SOLID CHC POPS FOR SLIGHTLY BETTER COVERAGE OF SHSN.
BEHIND THIS FRONT...ALL INDICATIONS SUGGEST WE`LL ONCE AGAIN ENTER
THE DEEP FREEZE FOR AT LEAST A FEW MORE DAYS FROM NEXT SUNDAY ONWARD
AS ARCTIC HIGH PRESSURE REASSERTS ITSELF ACROSS THE NORTHEAST. WISH
I COULD PAINT A MORE INTERESTING AND/OR COMFORTABLE PATTERN...BUT
ALL INDICATIONS SUGGEST VERY COLD AND DRY THROUGH THE END OF THE
MONTH.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
THROUGH 18Z MONDAY...VFR AND MVFR CONDITIONS CONTINUE THIS AFTN
AND EARLY EVENING. LGT SNOW SHOWERS CONTINUE TO AFFECT THE NORTH
COUNTRY...SO OVERALL VFR CONDITIONS WILL SEE MVFR CONDITIONS
WITHIN SNOW SHOWERS AHEAD OF COLD FRONT APPROACHING FROM THE NW.
MOST AREAS WILL SEE A BREAK IN SNOW SHOWERS FROM 19Z TO AT LEAST
00Z. SNOW SHOWERS WILL INCREASE NEAR 03Z IN THE SLV AS THE FRONT
APPROACHES...PRODUCING SNOW SQUALLS WITH IFR TO LIFR CONDITIONS.
DIFFICULT TO PINPT TIMING OF THIS FRONT...AS MODEL TRENDS
CONTINUE TO SLOW ITS PROGRESSION. AT THIS PT...EXPECT FRONT AND
IFR/LIFR CONDITIONS TO AFFECT KMSS BTWN 03Z-08Z...CPV 04Z-
10Z...KMPV 06Z- 11Z AND KRUT AFTER 08Z BUT WEAKENING. KSLK MAY
SEE IFR IN SNOW SHOWERS AHEAD OF THE FRONT WITHIN THE UPSLOPE SW
FLOW STARTING 21Z...WITH THE FRONT REACHING THE AREA AROUND 05Z-
10Z.
BEHIND THE FRONT...CONDITIONS WILL IMPROVE TO VFR AS SNOW SHOWERS
TAPER OFF. PSBL EXCEPTION AT KSLK IN CONTINUED UPSLOPE.
WINDS WILL BE GUSTY FROM THE S-SW AT 10-20KTS WITH GUSTS OF
20-30KTS...PSBLY HIGHER IN THE SLV. BEHIND THE FRONT WINDS WILL
GRADUALLY SUBSIDE...WITH GUSTS DIMINISHING AFTER DAYBREAK AS
WINDS SHIFT TO THE NW.
OUTLOOK 18Z MONDAY THROUGH FRIDAY...
18Z MONDAY THROUGH 21Z MONDAY...TRENDING VFR THOUGH SOME
LINGERING MVFR/IFR SHSN POSSIBLE AS ARCTIC FRONT CLEARS SOUTH OF
THE REGION.
21Z MONDAY ONWARD...MAINLY VFR WITH HIGH PRESSURE AND VERY COLD TEMPERATURES.
&&
.EQUIPMENT...
AS OF 340 AM EST SUNDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM BUT IT WILL
LIKELY BE OUT OF SERVICE THROUGH AT LEAST TUESDAY JANUARY 21.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...RJS/LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...KGM
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1244 PM EST SUN JAN 19 2014
.SYNOPSIS...
A DISTURBANCE IN THE JET STREAM WINDS ALOFT AND AN ARCTIC COLD
FRONT WILL PRODUCE PERIODS OF SNOW SHOWERS ACROSS THE NORTH
COUNTRY TODAY AND TONIGHT. OVERALL...SNOW ACCUMULATIONS WILL BE
LIGHT WITH 1 TO 3 INCHES IN GENERAL EXPECTED. BEHIND THE
FRONT...A RETURN OF MUCH COLDER AND DRIER CONDITIONS IS EXPECTED
FOR THE UPCOMING WEEK...WITH HIGHS ONLY IN THE SINGLE DIGITS
ABOVE ZERO AND LOWS IN THE SINGLE DIGITS TO TEENS BELOW FOR
MONDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 955 AM EST SUNDAY...SUFFICIENT MOISTURE ACROSS REGION THIS
MORNING...AND THIS COUPLED WITH SHORTWAVE TROUGH AND WARM AIR
ADVECTION HAS RESULTED IN RATHER WIDESPREAD LIGHT SNOW ACROSS THE
AREA...WITH SNOWFALL AMOUNTS ANYWHERE FROM A TRACE TO 3 INCHES.
AS SHORTWAVE DEPARTS THE AREA TOWARDS MIDDAY...LOOK FOR A DECREASE
IN PRECIPITATION OVER MUCH OF THE REGION. EXCEPTION WILL BE ACROSS
SAINT LAWRENCE VALLEY AND ADIRONDACKS WHERE PERSISTENT SOUTHWEST
FLOW WILL RESULT IN LIKELIHOOD OF MORE SNOW SHOWERS THIS
AFTERNOON. ACTIVITY WILL THEN INCREASE ACROSS THE REST OF THE REST
OF THE FORECAST AREA ONCE AGAIN LATER THIS AFTERNOON AND
ESPECIALLY THIS EVENING WITH APPROACH OF ARCTIC FRONT. GOING
FORECAST HAS THIS ALL COVERED FAIRLY WELL...SO NO SIGNIFICANT
CHANGES WITH LATEST UPDATE. HAVE UPDATED TEMPS TO REFLECT LATEST
CONDITIONS...BUT MAX TEMPS IN THE UPPER 20S TO LOWER 30S STILL
LOOK TO BE ON TRACK.
EARLIER DISCUSSION...
VERY LITTLE OVERALL CHANGE FROM PREVIOUS FORECAST THINKING FOR
TODAY AS THE ATMOSPHERE IS BEHAVING MUCH LIKE WE EXPECTED. LATEST
GUIDANCE CONTINUES TO SLOW DOWN THE APPROACH OF AN ARCTIC FRONT
WHICH NOW LOOKS TO AFFECT THE NORTH COUNTRY TOWARD THIS EVENING
AND TONIGHT...SO FOR TODAY WE`LL BE DEALING WITH A POTENT
SHORTWAVE TROUGH CURRENTLY OVER THE OHIO RIVER VALLEY WHICH WILL
SHIFT EASTWARD THROUGH THE MID-ATLANTIC STATES. LATEST WV IMAGERY
CONTINUES TO SUPPORT THE IDEA THAT THE BEST PVA SLIDES TO OUR
SOUTH TODAY...BUT 13KM RAP CONTINUES TO SHOW A PIECE OF ENERGY
BREAKING OFF AND TRACKING NORTHEAST THROUGH THE CWA THIS MORNING.
WITH THE EXCEPTIONAL PERFORMANCE OF THE RAP OVER THE LAST FEW DAYS
IT`S HARD TO IGNORE IT...AND OVERALL IT MAKES SENSE BASED ON THE
UPPER FLOW TRENDING SOUTHWESTERLY. THAT SAID...WE`LL SEE PERIODS
OF SNOW SHOWERS THIS MORNING THROUGH ABOUT MID-DAY...WITH A BREAK
IN THE ACTION THIS AFTERNOON AS THE SHORTWAVE ENERGY SHIFTS
NORTHEAST OF THE REGION AND WE AWAKE ANOTHER ROUND OF SNOW SHOWERS
ASSOCIATED WITH THE ARCTIC FRONT. OVERALL QPF WILL BE VERY LIGHT
WITH JUST A FEW HUNDREDTHS OF LIQUID EXPECTED...AMOUNTING TO JUST
A DUSTING TO MAYBE 2 INCHES THROUGH THE DAY. TEMPS WILL BE THE
LAST ABOVE NORMALS WE`LL SEE FOR AWHILE AND GENERALLY IN THE 20S
TO A FEW LOW 30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
AS OF 340 AM EST SUNDAY...FOR TONIGHT INTO MONDAY FOCUS TURNS
TOWARDS AN ARCTIC BOUNDARY WHICH WILL SWING NORTHWEST TO
SOUTHEAST THROUGH THE CWA. AS MENTIONED ABOVE...LATEST GUIDANCE
CONTINUES TO SLOW THE PROGRESSION OF SAID FEATURE WITH SOME
RESIDUAL LAKE ENHANCED SNOW SHOWERS NOW POSSIBLY LINGERING
THROUGH MID-DAY MONDAY ACROSS CENTRAL AND SOUTHERN AREAS.
OVERALL...FRONT SHOULD MOVE INTO NORTHWESTERN PORTIONS OF THE
REGION LATE THIS EVENING WITH LOCAL WRF`S AND RAP CONTINUING TO
SHOW FAVORABLE CONDITIONS FOR SNOW SQUALLS. THINKING ANOTHER
DUSTING TO 2 INCHES WILL BE POSSIBLE TONIGHT...WITH MUCH OF THAT
LIKELY OCCURRING IN A VERY SHORT PERIOD OF TIME. COME MONDAY
MORNING FRONT WILL BE SOMEWHERE ACROSS CENTRAL AND SOUTHERN
VERMONT WITH SOME LINGERING LAKE ENHANCED SHOWERS SHOWERS AROUND
ESPECIALLY ACROSS THE HIGHER TERRAIN...BUT AS DRIER AIR MOVES IN
UNDER STRONG CAA ON NORTHWEST FLOW SNOW SHOULD TAPER OFF BY THE
AFTERNOON HOURS. DAYTIME HIGHS IN THE TEENS WILL LIKELY BE
REACHED DURING THE MORNING HOURS...SLOWLY FALLING THROUGH THE DAY
WITH THE EXCEPTION BEING THE FAR SOUTHEAST CORNER OF VT WHERE
HIGHS WILL BE IN THE MID 20S AHEAD OF THE FRONT.
FOR MONDAY NIGHT AND TUESDAY SURFACE HIGH PRESSURE BUILDS INTO
THE REGION WITH CLEARING SKIES AND BONE CHILLING TEMPERATURES
EXPECTED. MONDAY NIGHT LOWS WILL FALL INTO THE SINGLE DIGIT TO
TEENS BELOW ZERO...AND WITH MODERATE GRADIENT FLOW REMAINING
BETWEEN THE BUILDING HIGH AND DEPARTING LOW WE`LL LIKELY BE
LOOKING AT SOME WIND CHILL ADVISORIES FOR PORTIONS OF NORTHERN
NEW YORK AND NORTHEAST VERMONT. WINDS WILL SLACKEN OFF FOR TUESDAY
WITH PARTLY SUNNY SKIES AND HIGHS ONLY IN THE THE SINGLE DIGITS
BELOW TO 10 ABOVE.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 212 AM EST SUNDAY...QUIET...COLD AND MAINLY DRY PATTERN WILL
BECOME LOCKED IN ACROSS THE EASTERN HALF OF THE U.S. DURING THE
MID TO LATE WEEK TIME FRAME AND LIKELY BEYOND AS ARCTIC AIR HAS A
DIRECT PATHWAY INTO OUR REGION. THIS IS A VERY STABLE
PATTERN...AND UNTIL MORE ORGANIZED ENERGY CAN CRASH EASTWARD
THROUGH THE HIGH-AMPLITUDE WESTERN CONUS RIDGE...THE CURRENT HIGH
AMPLITUDE PATTERN SHOULD MORE OR LESS HOLD IN PLACE FOR THE NEXT
10 DAYS. IN TERMS OF SENSIBLE WEATHER...TEMPERATURES WILL REMAIN
WELL BELOW NORMAL WEDNESDAY INTO FRIDAY THOUGH WITH SOME SLIGHT
AIRMASS MODERATION BY ABOUT 5 DEGREES EACH DAY. OVERNIGHT LOWS
CONSISTENTLY BELOW ZERO WITH COLDEST NIGHT OCCURRING TUESDAY NIGHT
WHEN WIDESPREAD 10 TO 20 BELOW READINGS LIKELY. A WEAK CLIPPER LOW
PASSING SOUTH OF THE AREA MAY SPREAD SOME CLOUDINESS AND PERHAPS A
BRIEF PERIOD OF FLURRIES/VERY LIGHT SNOW TO OUR SOUTHERN COUNTIES
ON THURSDAY...OTHERWISE MAINLY DRY WEATHER IS EXPECTED THROUGH
FRIDAY.
BY FRIDAY NIGHT SOUTHERLY FLOW RETURNS AS SFC RIDGE DEPARTS EAST
ALLOWING TEMPERATURES TO CLIMB SLOWLY...REACHING NEAR MID-WINTER
SEASONAL NORMS FOR ONE BRIEF DAY ON SATURDAY. ADDITIONAL NORTHERN
STREAM ENERGY ACCOMPANIED BY YET ANOTHER IMPRESSIVE ARCTIC BOUNDARY
TO THEN SWEEP INTO THE REGION BY LATER SATURDAY/SATURDAY NIGHT WHERE
I`LL MAINTAIN SOLID CHC POPS FOR SLIGHTLY BETTER COVERAGE OF SHSN.
BEHIND THIS FRONT...ALL INDICATIONS SUGGEST WE`LL ONCE AGAIN ENTER
THE DEEP FREEZE FOR AT LEAST A FEW MORE DAYS FROM NEXT SUNDAY ONWARD
AS ARCTIC HIGH PRESSURE REASSERTS ITSELF ACROSS THE NORTHEAST. WISH
I COULD PAINT A MORE INTERESTING AND/OR COMFORTABLE PATTERN...BUT
ALL INDICATIONS SUGGEST VERY COLD AND DRY THROUGH THE END OF THE
MONTH.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
THROUGH 18Z MONDAY...VFR AND MVFR CONDITIONS CONTINUE THIS AFTN
AND EARLY EVENING. LGT SNOW SHOWERS CONTINUE TO AFFECT THE NORTH
COUNTRY...SO OVERALL VFR CONDITIONS WILL SEE MVFR CONDITIONS
WITHIN SNOW SHOWERS AHEAD OF COLD FRONT APPROACHING FROM THE NW.
MOST AREAS WILL SEE A BREAK IN SNOW SHOWERS FROM 19Z TO AT LEAST
00Z. SNOW SHOWERS WILL INCREASE NEAR 03Z IN THE SLV AS THE FRONT
APPROACHES...PRODUCING SNOW SQUALLS WITH IFR TO LIFR CONDITIONS.
DIFFICULT TO PINPT TIMING OF THIS FRONT...AS MODEL TRENDS
CONTINUE TO SLOW ITS PROGRESSION. AT THIS PT...EXPECT FRONT AND
IFR/LIFR CONDITIONS TO AFFECT KMSS BTWN 03Z-08Z...CPV 04Z-
10Z...KMPV 06Z- 11Z AND KRUT AFTER 08Z BUT WEAKENING. KSLK MAY
SEE IFR IN SNOW SHOWERS AHEAD OF THE FRONT WITHIN THE UPSLOPE SW
FLOW STARTING 21Z...WITH THE FRONT REACHING THE AREA AROUND 05Z-
10Z.
BEHIND THE FRONT...CONDITIONS WILL IMPROVE TO VFR AS SNOW SHOWERS
TAPER OFF. PSBL EXCEPTION AT KSLK IN CONTINUED UPSLOPE.
WINDS WILL BE GUSTY FROM THE S-SW AT 10-20KTS WITH GUSTS OF
20-30KTS...PSBLY HIGHER IN THE SLV. BEHIND THE FRONT WINDS WILL
GRADUALLY SUBSIDE...WITH GUSTS DIMINISHING AFTER DAYBREAK AS
WINDS SHIFT TO THE NW.
OUTLOOK 18Z MONDAY THROUGH FRIDAY...
18Z MONDAY THROUGH 21Z MONDAY...TRENDING VFR THOUGH SOME
LINGERING MVFR/IFR SHSN POSSIBLE AS ARCTIC FRONT CLEARS SOUTH OF
THE REGION.
21Z MONDAY ONWARD...MAINLY VFR WITH HIGH PRESSURE AND VERY COLD TEMPERATURES.
&&
.EQUIPMENT...
AS OF 340 AM EST SUNDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM BUT IT WILL
LIKELY BE OUT OF SERVICE THROUGH AT LEAST TUESDAY JANUARY 21.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...RJS/LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...KGM
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS NORMAN OK
1105 AM CST SUN JAN 19 2014
.AVIATION...
GUSTY SOUTHWEST WINDS WILL DEVELOP ALL SITES. GUSTS
OVER 30KTS MAY OCCUR AT CSM/HBR/OKC/OUN THIS AFTN. WIND DIMINISH
QUICKLY AROUND SUNSET AND THEN SHIFT TO THE NORTH OVERNIGHT AS COLD
FRONT MOVES SOUTH ACROSS THE AREA. WINDS WILL BEGIN TO INCREASE
AFTER SUNRISE WITH GUSTS NEAR 20KTS POSSIBLE ACROSS WEST SITES BY
LATE IN THE FORECAST PERIOD. SKIES REMAIN CLEAR.
30
&&
.PREV DISCUSSION... /ISSUED 1033 AM CST SUN JAN 19 2014/
.UPDATE...
HAVE UPDATED THE FORECAST TO LOWER FORECAST DEWPOINTS FOR THIS
AFTERNOON... AND EXPAND THE RED FLAG WARNING DUE TO THESE LOWER
DEWPOINTS/RH VALUES FORECAST. 12Z OUN AND MOST REGIONAL SOUNDINGS
SHOW CONSIDERABLE DRY AIR ABOVE THE SURFACE TO ABOVE THE 850 MB
LEVEL. THIS VERY DRY AIR WILL ALLOW SURFACE DEWPOINTS TO LOWER
SIGNIFICANTLY ONCE TEMPERATURES WARM ENOUGH TO ALLOW MIXING BEYOND
THE INVERSION. THE AFTERNOON DEWPOINTS HAVE BEEN LOWERED ANOTHER 5
TO 10 DEGREES CLOSER TO THE RAP FORECAST. ..SPEG.
&&
.PREV DISCUSSION... /ISSUED 346 AM CST SUN JAN 19 2014/
DISCUSSION...
VERY WARM AIR WILL ARRIVE ON GUSTY SOUTHWEST WINDS THIS AFTERNOON.
A RED FLAG WARNING IS EFFECTIVE THEN FOR THE VERY DRY CONDITIONS.
THE COMING WEEK WILL SEE 3 FRONTAL PASSAGES - EARLY MONDAY,
WEDNESDAY, THEN SATURDAY. WHILE COOLER AIR WILL BRIEFLY FOLLOW
EACH, NO REALLY COLD AIR IS EXPECTED. TUESDAY AND THURSDAY WILL
LIKELY BE THE COOLER DAYS. NORTHWEST FLOW WILL DRIVE THESE FRONTS
AND MILD AIR MASSES SOUTH FOLLOWED QUICKLY BY WARM-UPS. NO
MECHANISM FOR PRECIPITATION IS FORECAST FOR THE NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 36 59 27 / 0 0 0 0
HOBART OK 68 34 59 26 / 0 0 0 0
WICHITA FALLS TX 69 37 64 29 / 0 0 0 0
GAGE OK 71 29 56 23 / 0 0 0 0
PONCA CITY OK 66 32 55 23 / 0 0 0 0
DURANT OK 66 40 64 32 / 0 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR OKZ004>040-042-
044-045.
TX...RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR TXZ083>090.
&&
$$
AREA FORECAST DISCUSSION
NWS NORMAN OK
1033 AM CST SUN JAN 19 2014
.UPDATE...
HAVE UPDATED THE FORECAST TO LOWER FORECAST DEWPOINTS FOR THIS
AFTERNOON... AND EXPAND THE RED FLAG WARNING DUE TO THESE LOWER
DEWPOINTS/RH VALUES FORECAST. 12Z OUN AND MOST REGIONAL SOUNDINGS
SHOW CONSIDERABLE DRY AIR ABOVE THE SURFACE TO ABOVE THE 850 MB
LEVEL. THIS VERY DRY AIR WILL ALLOW SURFACE DEWPOINTS TO LOWER
SIGNIFICANTLY ONCE TEMPERATURES WARM ENOUGH TO ALLOW MIXING BEYOND
THE INVERSION. THE AFTERNOON DEWPOINTS HAVE BEEN LOWERED ANOTHER 5
TO 10 DEGREES CLOSER TO THE RAP FORECAST. ..SPEG.
&&
.PREV DISCUSSION... /ISSUED 346 AM CST SUN JAN 19 2014/
DISCUSSION...
VERY WARM AIR WILL ARRIVE ON GUSTY SOUTHWEST WINDS THIS AFTERNOON.
A RED FLAG WARNING IS EFFECTIVE THEN FOR THE VERY DRY CONDITIONS.
THE COMING WEEK WILL SEE 3 FRONTAL PASSAGES - EARLY MONDAY,
WEDNESDAY, THEN SATURDAY. WHILE COOLER AIR WILL BRIEFLY FOLLOW
EACH, NO REALLY COLD AIR IS EXPECTED. TUESDAY AND THURSDAY WILL
LIKELY BE THE COOLER DAYS. NORTHWEST FLOW WILL DRIVE THESE FRONTS
AND MILD AIR MASSES SOUTH FOLLOWED QUICKLY BY WARM-UPS. NO
MECHANISM FOR PRECIPITATION IS FORECAST FOR THE NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 36 59 27 / 0 0 0 0
HOBART OK 68 34 59 26 / 0 0 0 0
WICHITA FALLS TX 69 37 64 29 / 0 0 0 0
GAGE OK 71 29 56 23 / 0 0 0 0
PONCA CITY OK 66 32 55 23 / 0 0 0 0
DURANT OK 66 40 64 32 / 0 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR OKZ004>040-042-
044-045.
TX...RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR TXZ083>090.
&&
$$