Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 12/19/14

AREA FORECAST DISCUSSION

NWS ALBANY NY

 446 PM EST WED DEC 17 2014

.SYNOPSIS...
THE COMBINATION OF LOW PRESSURE STRENGTHENING OFF THE
NORTHERN NEW ENGLAND COAST...AND AN UPPER LEVEL DISTURBANCE PASSING
THROUGH OVERNIGHT WILL KEEP SKIES MOSTLY CLOUDY...ALONG WITH SOME
PASSING RAIN AND SNOW SHOWERS...MOST FREQUENT ACROSS THE SOUTHERN
ADIRONDACKS AND SOUTHERN VERMONT. THURSDAY WILL BE
BLUSTERY WITH LINGERING SNOW SHOWERS ACROSS HIGHER
ELEVATIONS...ALTHOUGH SOME BREAKS IN THE CLOUDS WILL BE POSSIBLE
SOUTH OF THE CAPITAL REGION. SLIGHTLY COLDER AIR WILL SEEP INTO
THE REGION FROM THE NORTH FOR THURSDAY NIGHT AND FRIDAY...DESPITE
THE POSSIBILITY FOR SOME BREAKS IN THE CLOUDS TO DEVELOP.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 430 PM EST...HAVE MADE SOME MINOR ADJUSTMENTS TO THE GRIDDED
DATABASE...MAINLY TO INCREASE POPS A BIT MORE FROM ALBANY NORTH
LATER TONIGHT...PARTICULARLY ACROSS THE HIGHER TERRAIN...INTO THE
LIKELY TO CATEGORICAL RANGE.

WE WILL HAVE TO WATCH RADAR TRENDS CLOSELY OVERNIGHT...AS THE
LATEST RAP13 AND HRRR SUGGEST THAT A MID LEVEL LOW CENTER
ASSOCIATED A COMPACT YET POTENT SHORTWAVE CURRENTLY PASSING OVER
SOUTHERN MICHIGAN POSSIBLY CLOSES OFF SOMEWHERE ACROSS SOUTHERN
AREAS AS IT PASSES QUICKLY EAST/SOUTHEAST. THIS MAY ALLOW FOR SOME
ADDITIONAL MID LEVEL FORCING/DEFORMATION ACROSS CENTRAL AND
NORTHERN PORTIONS OF THE REGION...MAINLY AFTER MIDNIGHT. THIS
ADDITIONAL FORCING COULD ALLOW FOR SOME BURSTS OF SNOW TO
OCCUR...INITIALLY ACROSS HIGHER ELEVATIONS...THEN EVEN ACROSS SOME
VALLEY AREAS...FROM AROUND THE CAPITAL REGION NORTH TO THE LAKE
GEORGE/SARATOGA REGION. THIS COULD ALLOW FOR HIGHER
ACCUMS...PERHAPS INTO THE 2-5 INCH RANGE FOR SOME HIGHER
ELEVATIONS OF THE ADIRONDACKS...SOUTHERN VT...AND WESTERN MA.
ALSO...MANY VALLEY AREAS BETWEEN ALBANY AND LAKE GEORGE COULD
RECEIVE A QUICK COATING...TO JUST UNDER AN INCH OF SNOW LATER TONIGHT.

PREVIOUS DISCUSSION...

OTHERWISE...THE OCCLUDED FRONT HAS PASSED EAST AND NORTH OF THE
REGION. HOWEVER...TWO SHORTWAVES...ONE CURRENTLY LOCATED ACROSS
THE CENTRAL NYS/PA BORDER...AND ANOTHER OVER THE SOUTHERN GREAT
LAKES...WILL CONTINUE TRANSLATING EASTWARD OVERNIGHT. THE FIRST
ONE WILL ALLOW SHOWERS TO PERSIST THROUGH THIS
EVENING...ESPECIALLY ACROSS HIGHER ELEVATIONS OF THE EASTERN
CATSKILLS...TACONICS...AND BERKSHIRES. SOME LIGHT RAIN SHOWERS OR
DRIZZLE WILL OCCASIONALLY REACH THE VALLEY AREAS AS WELL THROUGH
EARLY TONIGHT. CLOUD TOPS ARE RELATIVELY SHALLOW...WITH CLOUD TOP
TEMPS GENERALLY IN THE -5 TO -8 C RANGE OR SLIGHTLY WARMER.
SO...AT LEAST FOR NOW...THERE APPEARS TO BE MINIMAL ICE CRYSTALS
IN THE CLOUDS...WITH JUST PERHAPS SOME SNOW GRAINS ACROSS THE
HIGHER ELEVATIONS OVER THE NEXT 3 HOURS.

LATER THIS EVENING...THE FIRST IMPULSE WILL PASS EAST OF THE
REGION...WITH THE NEXT ONE POISED UPSTREAM. THE COMBINATION OF
ENHANCED LOW LEVEL MOISTURE FROM THE NEARBY LAKES...AND ADDITIONAL
MID LEVEL MOISTURE ROTATING SOUTHEAST TO SOUTH FROM NORTH OF THE
GREAT LAKES SHOULD ALLOW FOR SOME SEEDER FEEDER PROCESSES...IN
ADDITION TO OVERALL COOLING MID LEVEL TEMPS...TO ALLOW FOR A
TRANSITION TO MAINLY SNOW SHOWERS ACROSS HIGHER TERRAIN...WITH
RAIN SHOWERS OR DRIZZLE GRADUALLY MIXING WITH...AND POSSIBLY
CHANGING TO SNOW OR SNOW GRAINS IN SOME VALLEY AREAS AFTER
MIDNIGHT. AGAIN...OVERALL CLOUD TOP TEMPS MAY NOT BE QUITE COLD
ENOUGH FOR DENDRITIC SNOW CRYSTALS...SO SNOW CONSISTENCY MAY BE
SOMEWHAT GRAINY IN NATURE...AND NOT CONDUCIVE FOR SIGNIFICANT
ACCUMS. AT THIS TIME...IT APPEARS THAT 1-3 INCHES WILL BE POSSIBLE
ACROSS HIGHER ELEVATIONS ACROSS THE SOUTHWEST ADIRONDACKS...AS
WELL AS ACROSS HIGHER...WEST FACING ELEVATIONS ACROSS SOUTHERN VT.
SOME LOCALLY HIGHER AMTS COULD OCCUR FOR ELEVATIONS ABOVE 1800 FT.
ALSO...PORTIONS OF THE BERKSHIRES COULD GET 1-2 INCHES LATE
TONIGHT...WITH PERHAPS SLIGHTLY HIGHER AMTS FOR ELEVATIONS ABOVE
1800 FT IN EASTERN BERKSHIRE CO.

IT APPEARS THAT LOW LEVEL DIRECTIONAL WIND SHEAR WILL PREVENT TRUE
SINGLE BANDED LAKE EFFECT SNOW TO OCCUR...BUT STILL EXPECT A
COMBINATION OF SYNOPTIC...AND OROGRAPHIC EFFECTS TO PRODUCE THE
OVERNIGHT SNOW IN HIGHER ELEVATIONS.

WINDS WILL INCREASE FROM THE WEST TO NORTHWEST OVERNIGHT...WITH
SOME GUSTS POSSIBLY REACHING 25-30 MPH BY DAYBREAK...ESP IN
FAVORABLE CHANNELED W/E VALLEYS...SUCH AS THE MOHAWK RIVER
VALLEY...AS WELL AS IN THE BERKSHIRES.

THE COMBINATION OF CLOUDS...AND INCREASING WIND SHOULD PREVENT
TEMPS FROM FALLING AS LOW AS THE MAV MOS SUGGESTS...AND IN SOME
AREAS...IT IS POSSIBLE THAT TEMPS MAY ONLY DROP TO NEAR OR EVEN
SLIGHTLY ABOVE FREEZING...ESP WITHIN THE IMMEDIATE MOHAWK RIVER
VALLEY/CAPITAL REGION AND UPPER HUDSON RIVER VALLEY. HAVE
THEREFORE WENT WITH...OR ABOVE THE SLIGHTLY WARMER MET MOS FOR
OVERNIGHT MINS.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
THURSDAY...AFOREMENTIONED SECOND SHORTWAVE IMPULSE SHOULD MOVE
GENERALLY EAST OF THE REGION IN THE MORNING. HOWEVER...SOME
LINGERING UPSLOPE SNOW SHOWERS WILL LIKELY PERSIST ACROSS PORTIONS
OF THE SW ADIRONDACKS...SOUTHERN VT...AND WESTERN MA. ADDITIONAL
ACCUMS OF AN INCH OR TWO COULD OCCUR WITHIN THE MORE PERSISTENT
AREAS OF SNOW SHOWERS. ELSEWHERE...THE MAIN STORY FOR THU SHOULD
BE GUSTY WINDS...WHICH MAY GUST UP TO 35 MPH OR SLIGHTLY
HIGHER...ESP IN PORTIONS OF THE MOHAWK VALLEY/CAPITAL REGION AND
BERKSHIRES. ALTHOUGH MOST AREAS NEAR AND NORTH OF INTERSTATE 90
SHOULD REMAIN MOSTLY CLOUDY TO OVERCAST...SOME BREAKS OF SUN WILL
BE MORE LIKELY TO THE SOUTH...WITH SKIES POSSIBLY BECOMING MOSTLY
SUNNY AT TIMES ACROSS PORTIONS OF THE MID HUDSON
VALLEY...LITCHFIELD CO CT...AND POSSIBLY EXTREME SE VT. IN THESE
AREAS...TEMPS COULD WARM INTO THE 40S. ELSEWHERE...EXPECT MAINLY
30S IN VALLEYS...AND UPPER 20S/LOWER 30S ACROSS HIGHER ELEVATIONS.

THU NT-FRI NT...A SURFACE TROUGH IS EXPECTED TO GRADUALLY SETTLE
SOUTHWARD LATE THU NT INTO FRI...WITH A SLIGHTLY COLDER...SHALLOW
AIR MASS IN ITS WAKE. AS THE TROUGH PASSES...IT COULD ALLOW FOR A
BRIEF RESURGENCE IN SNOW SHOWERS/FLURRIES...MAINLY ACROSS HIGHER
ELEVATIONS LATE THU NT. AS WINDS SHIFT MORE INTO THE NW TO N IN
THE WAKE OF THE TROUGH...ANY LAKE ENHANCED SNOW SHOWERS SHOULD
SHIFT INTO THE CENTRAL NYS...PERHAPS OCCASIONALLY GRAZING THE
CATSKILLS. ELSEWHERE...THE POTENTIAL FOR CLEARING SKIES WILL
INCREASE IN AT LEAST VALLEY AREAS DURING FRIDAY...WITH MAINLY
CLEAR SKIES ANTICIPATED FOR FRI NT. TEMP THU NT SHOULD FALL INTO
THE 20S IN MOST AREAS...WITH SOME TEENS POSSIBLE ACROSS THE
SOUTHERN ADIRONDACKS. FRI SHOULD BE CHILLY...WITH MAX TEMPS MAINLY
REACHING THE LOWER/MID 30S IN VALLEY AREAS...EXCEPT NEAR 40 ACROSS
THE MID HUDSON VALLEY AND SOUTHERN LITCHFIELD CO CT...WITH MAINLY
20S TO LOWER 30S EXPECTED ACROSS HIGHER ELEVATIONS. FRI NT SHOULD
BE COLDER...WITH MOST MIN TEMPS FALLING INTO THE LOWER/MID 20S IN
VALLEYS...AND TEENS ACROSS HIGHER TERRAIN.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
SATURDAY STILL LOOKS DRY WITH SEASONABLY CHILLY TEMPERATURES. AFTER
THAT...IT LOOKS AS IF WE WILL BE DEALING WITH A MAINLY WEAK SOUTHERN
STREAM DISTURBANCE...BUT THEN A POTENTIALLY MUCH STRONGER "PHASED"
SYSTEM AS HEAD TO CHRISTMAS EVE.

THE ONLY DAY THAT WE MIGHT SEE ANY SOME SUNSHINE WOULD BE
SATURDAY...OTHERWISE PLENTY OF CLOUDS WILL PERSIST. EITHER WAY LOOK
FOR HIGHS FROM THE UPPER 20S NORTHWEST TO LOOK TO MID 30S SOUTH.

BY SUNDAY...WE WILL BE DEALING WITH AN EASTERLY FLOW FROM HIGH
PRESSURE ANCHORED IN EXTREME EASTERN CANADA...AS WELL AS SOME SORT
OF WEAK WAVE DEVELOPING WELL SOUTH IN THE JETSTREAM. ALSO...THERE
MIGHT BE AN EVEN WEAKER WAVE IN THE NORTHERN BRANCH OF THE JETSTREAM
THAT MIGHT INTERACT WITH THE SOUTHERN ONE TO DEVELOP SOME SORT OF
INVERTED TROUGH LATE SUNDAY INTO MONDAY. THIS FEATURE...COMBINED
WITH AN EASTERLY FLOW...COULD TRIGGER ENOUGH LIFT TO PRODUCE WHAT
LOOKS TO BE NUISANCE TYPE PRECIPITATION...MOUNTAIN SNOW AND A VALLEY
RAIN/SNOW MIX SUNDAY INTO MONDAY. AGAIN...THIS IS NOT GOING TO BE A
BIG STORM BUT IT COULD PRODUCE SOME SLIPPERY ROADS...ESPECIALLY
SUNDAY NIGHT AND HIGHER ELEVATIONS. THE TIMING OF THIS POSSIBLE
EVENT IS STILL UNCERTAIN SO FOR NOW WE HAVE INCLUDED SLIGHT CHANCES
SATURDAY NIGHT...AND LOW CHANCES SUNDAY INTO SUNDAY NIGHT AND SLIGHT
CHANCES
MONDAY.

HIGHS SUNDAY WILL GENERALLY BE IN THE 30S...ABOVE FREEZING IN THE
VALLEYS. LOWS SUNDAY NIGHT WILL BE AROUND 30 IN MOST PLACES. HIGHS
MONDAY AGAIN IN THE 30S.

BY LATE MONDAY...THE EUROPEAN AND GFS FORECAST MODELS ARE
FORECASTING A MUCH STRONGER TROUGH ASSOCIATED WITH THE NORTHERN
BRANCH TO DIG IN THE NATION/S MID SECTION. THIS TROUGH IS FORECAST
TO INTERACT WITH SOUTHERN STREAM ENERGY TO PRODUCE WHAT COULD BE A
POWERFUL STORM AS WE HEAD INTO LATE TUESDAY AND WEDNESDAY.

THE TRACK OF THIS STORM LOOKS TO BE ALONG OR NEAR THE APPALACHIAN
MOUNTAINS...WELL TO THE WEST OF THE HUDSON VALLEY. IT WOULD IMPACT
OUR REGION MAINLY ON CHRISTMAS EVE. A STORM WITH THIS TRACK WOULD
LIKELY BRING MOSTLY RAIN...PERHAPS A LITTLE WINTRY MIX ON THE FRONT
SIDE. AS IT MOVES UP TO OUR NORTHWEST...IT WOULD PULL AIR IN COLD
ENOUGH TO PERHAPS SWITCH LEFTOVER RAIN SHOWERS INTO SNOW SHOWERS BY
CHRISTMAS EVE NIGHT.

THIS STORM MIGHT BRING SOME STRONG WIND TO THE HIGHER TERRAIN
WEDNESDAY...AS IT LOOKS SIMILAR TO THE SETUP OF THE GREAT
APPALACHIAN STORM OF 1950 AS WELL AS THE "CLEVELAND BOMB" OF 1978.
HEAVY RAIN MIGHT TRIGGER SOME HYDRO ISSUES AS WE STILL HAVE A BIT OF
SNOW TO MELT IN THE MOUNTAINS.

BEING NEARLY A WEEK AWAY A LOT OF THE SYNOPTIC SETUP COULD
CHANGE...BUT THIS STORM DEFINITELY BEARS WATCHING.

HIGHS ON WEDNESDAY LOOK TO BE MAINLY IN THE 40S...DROPPING TO BELOW
FREEZING BY LATE CHRISTMAS EVE NIGHT.

&&

.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
AN UPPER LEVEL DISTURBANCE WILL CONTINUE TO PLAGUE THE SITES
THROUGH THE EVENING PEAK...WITH VERY SLOW IMPROVING TREND TO MVFR
KGFL/KPSF/KALB EXPECTED. THIS WILL BE DUE TO SLIGHTLY DRIER AIR
ADVECTING IN THE FROM THE WEST...AND A BREEZE ALSO PICKING UP FROM
THE WEST 5-10KTS THROUGH THIS EVENING.

CIGS AT KPOU LOOK TO REACH INTO THE VFR THRESHOLD TONIGHT BUT WILL
LIKELY REMAIN MVFR OR EVEN LOW MVFR (EXTRA FUEL REQUIRED) AT KPSF.

BY THURSDAY...THE WIND WILL 10-15KTS WITH GUSTS 20-25 KTS (HIGHEST
AT KPSF AND KALB). THE WIND SHOULD HELP SCOUR CLOUDS OUT A
LITTLE...BUT STILL EXPECT CIGS...REACHING BARELY INTO THE VFR RANGE
(EXCEPT HOLDING AT HIGH MVFR AT KPSF) AFTER ABOUT 13Z THURSDAY.

SHOWERS COULD IMPACT THE TAFS MAINLY EARLY THIS AFTERNOON...SO WE
ASSIGNED A VCSH AT ALL THE TAFS EXCEPT KPOU WHERE THE THREAT WAS
LOWEST. SHOWERS COULD HELP REDUCE VISIBILITIES VERY BRIEFLY DOWN TO
LIFR AT KALB/KPSF/ AND KGFL.

OUTLOOK...

THURSDAY NIGHT: NO OPERATIONAL IMPACT.  NO SIG WX.
FRIDAY: NO OPERATIONAL IMPACT.  NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT.  NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT.  NO SIG WX.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.

&&

.HYDROLOGY...
NO HYDROLOGIC CONCERNS THROUGH THE REMAINDER OF THE WEEK.

ADDITIONAL LIGHT RAIN OR SNOW SHOWERS WILL CONTINUE INTO TONIGHT.
BASIN AVERAGE PRECIP AMOUNTS WILL BE LIGHT...GENERALLY LESS THAN A
QUARTER OF AN INCH. ONLY VERY MINOR RISES ARE EXPECTED ON RIVERS
AND STREAMS...WITH MOST RIVER FLOWS EXPECTED TO REMAIN FAIRLY
STEADY.

SOME ADDITIONAL LIGHT MOUNTAIN SNOW SHOWERS ARE POSSIBLE THURSDAY
INTO FRIDAY...BUT THESE VERY BE FAIRLY LIMITED AND WON/T HAVE ANY
IMPACT ON AREA WATERWAYS. TEMPERATURES LOOK TO BE A LITTLE COLDER
FOR THURS/FRI...WHICH WILL LIMIT THE AMOUNT OF SNOW MELT THAT
OCCURS. MAINLY DRY WEATHER IS EXPECTED FOR THE WEEKEND...WITH JUST
A LOW CHANCE FOR SOME LIGHT SNOW.

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. 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...FRUGIS/KL
NEAR TERM...KL
SHORT TERM...KL
LONG TERM...HWJIV
AVIATION...HWJIV
HYDROLOGY...KL








AREA FORECAST DISCUSSION

NWS ALBANY NY

 1251 AM EST WED DEC 17 2014

.SYNOPSIS...
A WEAK STORM WILL BRING PERIODS OF LIGHT RAIN ALONG WITH
SOME FOG OVERNIGHT. THERE MAY BE POCKETS OF FREEZING RAIN OVER THE
ADIRONDACKS...GREEN MOUNTAINS AND BERKSHIRES. SOME LINGERING RAIN
AND SNOW SHOWERS WILL BE AROUND FOR WEDNESDAY INTO WEDNESDAY
NIGHT...BEFORE DRIER AIR AND SLIGHTLY COLDER TEMPERATURES RETURN TO
THE REGION FOR LATER IN THE WEEK.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS 1251 AM EST...AN OCCLUDED BOUNDARY IS IN THE PROCESS OF MOVING
ACROSS THE REGION FROM SOUTH TO NORTH. THE PARENT LOW OF THIS
STORM IS LOCATED OVER SOUTHERN ONTARIO...WITH A NEW SURFACE LOW
DEVELOPING ALONG THE STORM/S TRIPLE POINT NEAR NORTH
JERSEY/NYC/LONG ISLAND.

STEADY RAINFALL AHEAD OF THIS BOUNDARY HAS ENDED OVER MOST OF THE
REGION...EXCEPT WESTERN NEW ENGLAND. EVEN THERE...STEADY RAINFALL
LOOKS TO BE EXITING TO THE NORTH AND EAST OVER THE NEXT HOUR OR
TWO. WE WILL KEEP CHC TO LIKELY POPS IN PLACE THROUGH THE
REMAINDER OF THE OVERNIGHT HOURS...AS UPSTREAMS RADAR ARE STILL
SHOWING SOME SCATTERED RAIN SHOWERS THAT MAY WORK ITS WAY INTO OUR
AREA. THE 02Z 3KM HRRR SHOWS ACTIVITY REMAINING OVER EASTERN AREAS
AS WELL THROUGH THE OVERNIGHT HOURS...AS THE STRENGTHENING SFC
LOW NEAR THE COAST WILL HELP TO REDEVELOP RAINFALL FOR AREAS FROM
THE HUDSON RIVER ON EASTWARD.

IN THE MAJORITY OF THE REGION...TEMPS ARE ABOVE FREEZING IN
THE MID TO UPPER 30S. HOWEVER...A FEW LOCATIONS WITHIN SHELTERED
ELEVATED VALLEYS OF SOUTHERN VT...THE SOUTHERN ADIRONDACKS...AND
THE BERKSHIRES...ARE STILL SITTING AT 32 DEGREES. THIS MAY ALLOW
FOR SOME LIGHT FREEZING RAIN IN THOSE ISOLATED LOCATIONS...WITH A
COATING TO A TENTH OF AN INCH OF ICE POSSIBLE THROUGH THE
REMAINDER OF THE OVERNIGHT HOURS. WE HAVE BEEN HANDLING THIS
ISOLATED FREEZING RAIN THREAT WITH SPECIAL WEATHER STATEMENTS AND
UPDATES VIA SOCIAL MEDIA...AS COVERAGE IS TOO SMALL TO WARRANT A
WINTER WEATHER OR FREEZING RAIN ADVISORY. STILL...THERE MAY BE
SOME SLICK SPOTS IN THE USUAL COLDER LOCATIONS...SO CAUTION IS
URGED IF TRAVELING IN THESE LOCATIONS THROUGH THE REMAINDER OF THE
OVERNIGHT HOURS. TEMPS OVERNIGHT LOW TO MAINLY HOLD STEADY CLOSE
TO THEIR CURRENT READINGS.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY/...
TOMORROW...THE SURFACE WILL LOW WILL BEGIN TO MOVE EAST OF THE GULF
OF MAINE. HOWEVER...THE UPPER AIR LOW WILL STILL BE JUST TO OUR
NORTH WITH A SHORT WAVE TROUGH TO WORK ON THROUGH. PRECIPITATION
WILL TURN MORE SHOWERY BUT PERSIST...ESPECIALLY TO THE EAST OF THE
HUDSON VALLEY.  SLIGHTLY COLDER AIR WILL FILTER INTO THE
REGION...FIRST ALOFT...EVENTUALLY TRANSLATING DOWN TO THE SURFACE.

THERE COULD BE A FEW BREAKS OF AFTERNOON SUNSHINE IN THE MID HUDSON
VALLEY WITH HIGHS ONCE AGAIN PEAKING IN THE UPPER 40S. ELSEWHERE
CLOUDS LOOK TO HANG TOUGH WITH HIGHS 40-45 IN THE REMAINING VALLEY
AREAS (INCLUDING THE CAPITAL REGION)...MID OR UPPER 30S ACROSS THE
HIGHER TERRAIN WHERE IT WILL BE COLD ENOUGH FOR SHOWERS OF RAIN TO
MIX WITH OR CHANGE TO SNOW. THERE COULD PERHAPS BE A LITTLE
ACCUMULATIONS ACROSS THE HIGHER TERRAIN OF THE ADIRONDACKS.

TOMORROW NIGHT...THE UPPER AIR LOW AND SHORT WAVE WILL BE PUSHING
OFFSHORE BUT CYCLONIC FLOW WILL PERSIST WITH MORE CLOUDS AND MAINLY
MOUNTAIN SNOW SHOWERS. WITH TEMPERATURES FALLING TO FREEZING OR
LOWER (MID 20S HIGHER TERRAIN)...ANY SNOW SHOWERS WILL STICK AND WE
DO EXPECT MINOR ACCUMULATIONS IN THE MOUNTAINS OF 1-4 INCHES (MAINLY
THE ADIRONDACKS AND SOUTHERN GREENS...BUT OTHER HILLTOPS COULD
CERTAINLY SEE A DUSTING).

THURSDAY WILL BE A BRISK DAY WITH PARTIAL SUNSHINE  TO THE LEE OF
THE CATSKILLS...WHILE MOST OTHER AREAS STAY CLOUDY OR MOSTLY CLOUDY
THANKS TO LAKE ENHANCED CLOUDS AND STILL A CYCLONIC FLOW. LAKE
ENHANCED SNOW SHOWERS WILL BE SCATTERED OVER THE HIGHER TERRAIN WITH
PERHAPS A LITTLE MORE ADDITIONAL ACCUMULATIONS. VALLEY AREAS SHOULD
SEE NOTHING MORE THAN FLURRIES OR A FEW LIGHT SHOWERS OR RAIN OR
SNOW.

HIGH TEMPERATURES WILL BE AROUND 40 IN THE VALLEYS...LOWER TO MID
30S ACROSS THE HIGHER TERRAIN. THE WIND WILL BE OUT OF THE WEST
10-15 MPH WITH SOME GUSTS TO 25 MPH ACROSS THE HIGHER
TERRAIN...MOHAWK VALLEY AND CAPITAL REGION.

THURSDAY NIGHT AND FRIDAY...SHOULD BE MAINLY DRY...CONTINUED BRISK.
ANY SHOWERS SHOULD BE MAINLY CONFINED TO THE HIGHER TERRAIN PERHAPS
ADDING ANOTHER INCH OR SO IN SPOTS. VALLEYS WILL BE VARIABLY CLOUDY
WITH SOME PARTIAL CLEARING AT TIMES. LOWS THURSDAY NIGHT WILL BE IN
THE 20S. HIGHS FRIDAY WILL BE IN THE MID TO UPPER 30S IN THE
VALLEYS...MID 30S TO LOWER 30S ACROSS THE HIGHER TERRAIN. THESE
VALUES ARE ABOUT RIGHT ON THE MARK FOR MID DECEMBER.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
LOOKING AT DRY WEATHER TO START AND END THE LONG TERM PERIOD AS
HIGH PRESSURE DOMINATES FRIDAY INTO SATURDAY...AND AGAIN MONDAY INTO
TUESDAY. IN BETWEEN...MEDIUM RANGE GUIDANCE CONTINUES TO DEVELOP A
COASTAL LOW OFF THE EAST COAST THIS WEEKEND...HOWEVER THERE IS MUCH
UNCERTAINTY IN THE FORECAST AS THE MODELS ARE NOT OFFERING
MODEL-TO-MODEL OR RUN-TO-RUN CONSISTENCY. THERE IS A LARGE SPREAD IN
THE ENSEMBLE GUIDANCE REGARDING THE TIMING...TRACK AND STRENGTH OF
THE LOW...SO HAVE FAVORED GUIDANCE FROM THE WEATHER PREDICTION
CENTER TO ENSURE FORECAST CONSISTENCY. WITH SUCH UNCERTAINTY IN THE
FORECAST...HAVE ONLY FORECAST CHANCE POPS SATURDAY NIGHT INTO SUNDAY
NIGHT...WITH THE HIGHEST POPS ON SUNDAY AND ACROSS SOUTHERN AREAS.

TEMPERATURE WISE...LOWS FRIDAY NIGHT WILL BE IN THE TEENS TO LOWER
20S. HIGHS SATURDAY IN THE UPPER 20S TO MID 30S. LOWS SATURDAY NIGHT
THROUGH MONDAY NIGHT WILL BE IN THE UPPER TEENS AND 20S. HIGHS
SUNDAY THROUGH TUESDAY GENERALLY IN THE UPPER 20S AND 30S.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
IFR CONDITIONS TO PREVAIL THROUGH THE OVERNIGHT INTO WEDNESDAY
MORNING AS AN OCCLUDED BOUNDARY GRADUALLY MOVES ACROSS THE REGION.
THE BULK OF THE RAINFALL IS OVER HOWEVER LOW CEILINGS AND POOR
VISIBILITIES WILL CONTINUE WITH RELATIVELY MILD AND MOIST AIR OVER
THE REMAINING SNOWPACK. BY MID TO LATE MORNING CONDITIONS WILL BEGIN
TO SLOWLY IMPROVE...HOWEVER VFR CONDITIONS ARE NOT EXPECTED TO
DEVELOP UNTIL MID TO LATE AFTERNOON AT KPOU AND IN THE EVENING AT
KALB AND KGFL WITH MVFR LINGERS AT KPSF THROUGH 06Z/THURSDAY.

CALM WINDS WILL BECOME WESTERLY ON THURSDAY. THE WESTERLY WINDS WILL
INCREASE IN SPEED BY MID TO LATE AFTERNOON WITH GUSTS EXPECTED AT
KALB AND KPSF.

OUTLOOK...
THU NIGHT-SAT: NO OPERATIONAL IMPACT.  NO SIG WX.
SAT NIGHT-SUN: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.

&&

.HYDROLOGY...
NO HYDROLOGIC CONCERNS THROUGH THE REMAINDER OF THE WEEK.

AFTER STEADY RAIN ENDS EARLY THIS MORNING...THE SYSTEM MOVING
THROUGH THE REGION WILL ALLOW FOR SOME ADDITIONAL LIGHT RAIN OR
SNOW SHOWERS LATER TODAY INTO TONIGHT. BASIN AVERAGE PRECIP
AMOUNTS WILL BE LIGHT...GENERALLY LESS THAN A QUARTER OF AN INCH.
ONLY VERY MINOR RISES ARE EXPECTED ON RIVERS AND STREAMS...WITH
MOST RIVER FLOWS EXPECTED TO REMAIN FAIRLY STEADY.

SOME ADDITIONAL LIGHT MOUNTAIN SNOW SHOWERS ARE POSSIBLE THURSDAY
INTO FRIDAY...BUT THESE VERY BE FAIRLY LIMITED AND WON/T HAVE ANY
IMPACT ON AREA WATERWAYS. TEMPERATURES LOOK TO BE A LITTLE COLDER
FOR THURS/FRI...WHICH WILL LIMIT THE AMOUNT OF SNOW MELT THAT
OCCURS. MAINLY DRY WEATHER IS EXPECTED FOR THE WEEKEND...WITH JUST
A LOW CHANCE FOR SOME LIGHT SNOW.

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. 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...FRUGIS/HWJIV/GJM
NEAR TERM...FRUGIS
SHORT TERM...HWJIV
LONG TERM...GJM
AVIATION...IAA
HYDROLOGY...FRUGIS







AREA FORECAST DISCUSSION

NWS MOUNT HOLLY NJ

 944 PM EST THU DEC 18 2014

.SYNOPSIS...
A LOW PRESSURE SYSTEM OVER PRINCE EDWARD ISLAND WILL TRACK SLOWLY
TO THE NORTHEAST. HIGH PRESSURE OVER THE NORTHERN GREAT LAKES
WILL MOVE INTO THE OHIO VALLEY OVERNIGHT. LOW PRESSURE IS EXPECTED
TO FORM OVER THE GULF STATES FRIDAY NIGHT AND TRACK ACROSS GEORGIA
SATURDAY. A COLD FRONT MAY MOVE THROUGH THE EASTERN SEABOARD ON
CHRISTMAS EVE.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
SINCE THE TRUNDLING CLOSED LOW PRESSURE SYSTEM FROM LAST WEEK, THE
NORTHEASTERN CONUS HAS NOT BEEN ABLE TO SHAKE THE PLETHORA OF LOW
CLOUDINESS STUCK UNDERNEATH THE INVERSION, EVEN AFTER CHANGING AIR
MASSES. TONIGHT SEEMS NOT MUCH DIFFERENT. IN ADDITION, WE DO HAVE
SOME MID TO HIGH LEVEL CLOUDS MOVING THROUGH OUR CWA ASSOCIATED
WITH A WEAKENING SHORT WAVE. WHILE 88DS ARE SHOWING PCPN ALOFT,
NONE IS MAKING IT TO THE GROUND. THE FREEZING SNIZZLE IN UPSTATE
NEW YORK (DONT RECALL THIS HAPPENING TWICE IN TWO CONSECUTIVE WEEKS)
APPEARS TO NOT BE GETTING CLOSE TO OUR POCONOS. FOR THE OVERNIGHT
UPDATE, WE DID INCREASE CLOUD COVER AND BUMPED UP TEMPS,
ESPECIALLY IN THE NWRN TWO THIRDS OF OUR CWA WHERE WE ARE SOLIDLY
OVERCAST UPSTREAM. THE SOUTHEASTERN THIRD, THERE ARE SOME LOW
CLOUDS BREAK, SO KEPT THOSE MINS SIMILAR, BUT SHOWED MORE OF A
LATE AT NIGHT SPIRAL.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
LATEST WRF, RAP SHOWING MORE MOISTURE TRAPPED UNDERNEATH THE
INVERSION ON FRIDAY WITH CONVECTIVE TEMPS WITHIN REACH. WE MADE IT
CLOUDIER. LAST WEEK, WE FOUND A WAY TO STILL MAKE MAX TEMPS IN
SPITE OF THE CLOUDS, SO LEFT THEM THE SAME.

&&

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
MID-LEVEL FLOW THE NEXT COUPLE OF DAYS IS RATHER FLAT THOUGH A
CHANGE TO THAT PATTERN APPEARS LIKELY BY THE END OF THE WEEKEND. A
DEEP TROUGH EMERGES ACROSS THE CENTRAL U.S. BY TUESDAY AS MULTIPLE
PACIFIC NORTHWEST WAVES ROUND THE BASE OF THE TROUGH AND ACROSS OUR
REGION...WE ARE HEADING FOR A VERY UNSETTLED PERIOD BY EARLY NEXT
WEEK.

FRIDAY NIGHT - SATURDAY...LOOKS DRY. FRIDAY SHOULD BE DOMINATED BY
GREAT LAKES HIGH PRESSURE WHICH SHOULD YIELD PARTY CLOUDY SKIES.

SATURDAY NIGHT AND SUNDAY...AN INVERTED TROUGH MAY THROW BACK SOME
MOISTURE ACROSS THE  AREA AS A WEAK WAVE OF LOW PRESSURE MOVES WELL
OFFSHORE OF OUR REGION. ONLY HAVE SLIGHT CHANCE POPS ACROSS THE
NORTHEASTERN PORTION OF THE CWA AS THAT LOOKS LIKE THE MOST
FAVORABLE LOCATION FOR THE TONGUE TO MOISTURE TO REACH. GIVEN THE
OVERNIGHT TIMING PRECIP COULD FALL AS RAIN SNOW MIX OR ALL SNOW.

MONDAY - TUESDAY...LOW PRESSURE MOVES OFF THE CAROLINA COAST AND OUT
TO SEA ON TUESDAY. THIS LOW WILL HELP LIFT A WARM FRONT ASSOCIATED
WITH A LARGE AND DEVELOPING LOW PRESSURE SYSTEM OVER THE MIDDLE OF
THE CONUS INTO THE AREA. ONSHORE FLOW AHEAD OF THE SYSTEM AND WARM
AIR MOVING IN WITH THE FRONT WILL ALLOW FOR A WARMING LOW-LEVEL
THERMAL PROFILE SO PRECIP SHOULD BE PRIMARILY LIQUID. MID-RANGE
CHANCE POPS WILL PERSIST MONDAY...MONDAY NIGHT...AND TUESDAY.

WEDNESDAY...STILL WATCHING A LARGE LOW PRESSURE FORM TO OUR WEST AND
TRACK INTO THE GREAT LAKES REGION ON WEDNESDAY. THIS WOULD KEEP OUR
REGION UNDER A WARMING THERMAL PROFILE WITH A LOT OF MOISTURE TO
WORK WITH. WHAT IS INTERESTING WITH THE LATEST MODEL RUNS IS HOW
THEY ARE SEEMINGLY WEAKENING THE PRIMARY LOW AS IT MOVES INTO THE
LAKES ALLOWING FOR ANOTHER, STRONGER, PIECE OF PAC NW ENERGY TO
PRODUCE CYCLOGENESIS ACROSS THE MID-ATLANTIC. IT APPEARS THAT CHRISTMAS
EVE WL BE A DAY W/ MOISTURE, WINDS, AND POSSIBLY CONVECTION. LKLY
POPS ARE IN THE FCST.

THURSDAY...CHRISTMAS DAY - DEEP LAYER ZONAL FLOW WILL FILL IN
ACROSS THE AREA. DRY CONDITIONS XPCTD AS THE COLD FRONT SHOULD BE
E OF THE AREA. A DEEP STACKED LOW WILL BE OVER THE EASTERN GREAT
LAKES. RIGHT NOW "COOL AND BRZY" COULD BE THE WX WORDS FOR THE DAY.

&&

.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

00Z TAFS WILL BE VFR.

TONIGHT...A VFR CIG IS FORECAST. FOR KACY AND KMIV THIS IS MAINLY
DUE TO MID LEVEL CLOUDS. AT THE KPHL AIRPORTS, ITS A COMBINATION
OF A STRATOCU CIG AROUND 4K AND THE MID LEVEL CLOUD DECK. AT KRDG
AND KABE ITS MAINLY A STRATOCU DECK AT AROUND 3500 FEET. THERE
WILL BE MVFR CIGS AT AIRPORTS FARTHER TO THE NORTHWEST AND MIGHT
MAKE IT INTO THESE LATTER TERMINALS. WE DID AMEND SOME OF THE
TERMINALS DOWNWARD. WEST TO NORTHWEST WINDS SHOULD AVERAGE LESS
THAN 10 KNOTS.

FRIDAY...GOING MORE PESSIMISTICALLY WITH VFR CIGS AND EXPECTING A
STRATOCU CIG TO EITHER PERSIST NORTHWEST TO TERMINALS, OR DEVELOP
ELSEWHERE DURING THE DAY. MVFR CIGS POSSIBLE HIER TERRAIN
AIRPORTS. NORTHWEST WINDS SHOULD BE SLIGHTLY LESS THAN TODAY WITH
SUSTAINED SPEEDS AROUND 10 KNOTS AND PEAK GUSTS CLOSER TO 20
KNOTS. LATE IN THE DAY WE ARE PREDICTING THE GUSTS AND VFR CIGS
SHOULD NO LONGER OCCUR.

OUTLOOK...
FRIDAY NIGHT - SATURDAY...VFR. NORTHWEST WINDS VEER TOWARDS THE
NORTH-NORTHEAST BY SATURDAY.

SUNDAY - MONDAY...SUB-VFR POSSIBLE WITH SCATTERED RAIN/SNOW SHOWERS.

TUESDAY...VFR.

&&

.MARINE...
THE SMALL CRAFT ADVISORY NORTHERN WATERS WILL BE ALLOWED TO
EXPIRE AT 10 PM. GUIDANCE IS SHOWING A PAINFULLY SLOW, BUT STEADY
DROP OFF IN WINDS.

GUSTS NEAR OR ABOVE 20 KT WILL BE POSSIBLE THROUGH THE OVERNIGHT.

SUB SMALL CRAFT ADVISORY CONDITIONS EXPECTED ON FRIDAY.


OUTLOOK...
FRIDAY NIGHT...MOSTLY SUB-ADVISORY CONDITIONS ARE EXPECTED. SOME
NORTHWEST WIND GUSTS COULD STILL BE IN THE 20 PLUS KNOT RANGE,
THOUGH. CONFIDENCE: ABOVE AVERAGE.

SATURDAY - SUNDAY...SUB-SCA EXPECTED FOR THE MOST PART. SEAS REMAIN
AROUND 3 TO 4 FEET.  CONFIDENCE: AVERAGE TO SLIGHTLY BELOW AVERAGE.

MONDAY - TUESDAY...SCA CONDITIONS SHOULD PRESENT THEMSELVES LATER
ON MONDAY UNDER A STRENGTHENING EASTERLY FLOW AND BUILDING SEAS.
CONFIDENCE: AVERAGE.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...GIGI
NEAR TERM...GIGI
SHORT TERM...99
LONG TERM...99
AVIATION...GIGI/99
MARINE...GIGI/99






AREA FORECAST DISCUSSION

NWS CHARLESTON SC

 922 PM EST THU DEC 18 2014

.SYNOPSIS...
HIGH PRESSURE WILL PREVAIL INTO FRIDAY. UNSETTLED WEATHER IS
EXPECTED MUCH OF THE FRIDAY NIGHT THROUGH TUESDAY NIGHT PERIOD AS
SEVERAL DISTURBANCES AND EVENTUALLY A COLD FRONT TOWARD THE MIDDLE
OF NEXT WEEK AFFECT THE AREA.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
HIGH PRESSURE WILL EXTEND ACROSS THE AREA TONIGHT. A WEAK SURFACE
TROUGH WILL SHIFT SOUTH OVERNIGHT. CIRRUS CLOUDS WILL TRAVERSE THE
SOUTHEAST U.S. THROUGH THE NIGHT RESULTING IN MOSTLY CLEAR TO
PARTLY CLOUDY SKIES. LOWS WILL RANGE FROM THE MID-UPPER 30S INLAND
TO THE MID 40S AT THE BEACHES.

CHANGE SUMMARY FOR THE LATE EVENING UPDATE...
* NUDGED LOW TEMPERATURES DOWN IN A FEW LOCATIONS INCLUDING THE
  MORE RURAL AREAS OF UPPER AND LOWER CHARLESTON COUNTIES...MAINLY WEST
  OF HIGHWAY 17 AS WELL AS THE RURAL AREAS OF BEAUFORT COUNTY AWAY
  FROM THE BROAD RIVER/INLAND WATERWAYS.
* MODIFIED HOURLY DEWPOINTS BASED ON A 50/50 BLEND OF GLAMP AND
  RAP GUIDANCE.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
FRIDAY...MAINLY JUST AN INCREASE IN MID AND UPPER LEVEL CLOUDS
THROUGH THE DAY WITH NO RAINFALL EXPECTED. TEMPERATURES SHOULD CLIMB
SLIGHTLY ABOVE NORMAL INTO THE LOWER TO MID 60S...WARMEST GENERALLY
SOUTH OF I-16 AND WEST OF I-95. RAIN SHOULD SPREAD INTO THE AREA
FROM THE WEST FRIDAY NIGHT AS DEEPER MOISTURE MOVES IN AHEAD OF LOW
PRESSURE NEAR THE CENTRAL GULF COAST. LOWS SHOULD RANGE FROM THE
LOWER TO MID 40S NORTH AND WEST TO CLOSER TO 50 ALONG THE COAST.

SATURDAY...PRETTY WET AT LEAST THE FIRST PART OF THE DAY WITH
LOWERING RAIN CHANCES FROM WEST TO EAST AS THE DEEPER MOISTURE AND
FORCING SHIFT OFFSHORE. THE QUICK PACE OF THE SYSTEM MEANS THERE
WILL NOT BE A LOT OF RAIN...WITH MOST PLACES LIKELY ONLY GETTING NO
MORE THAN A FEW TENTHS OF AN INCH. WILL BE A RATHER CHILLY DAY WITH
THE HIGH PRESSURE WEDGE IN PLACE LEADING TO CLOUDY SKIES AND COOL
NORTH/NORTHEAST FLOW. OPTED TO STAY BELOW MOS GUIDANCE FOR HIGHS
GIVEN THE PATTERN...MAINLY AROUND 50 NEAR LAKE MOULTRIE WITH LOWER
TO MID 50S ELSEWHERE EXCEPT UPPER 50S TO NEAR 60 NEAR LUDOWICI AND
DARIEN. SATURDAY NIGHT SHOULD BE DRY ALTHOUGH MOISTURE WILL BE
INCREASING AGAIN FROM THE SOUTH AHEAD OF ANOTHER WAVE OF LOW
PRESSURE IN THE NORTHEAST GULF OF MEXICO. LOWS MAINLY AROUND 40
NORTH AND WEST AND NEAR 50 SOUTH AND EAST.

SUNDAY...THERE ARE SOME TIMING UNCERTAINTIES REGARDING AMOUNT OF
DEEP MOISTURE MOVING IN FROM THE SOUTH...WITH THE ECMWF A BIT MORE
AGGRESSIVE THAN THE GFS. FOR NOW WE MAINTAINED HIGHEST CHANCES /30
PERCENT/ NEAR THE COAST AND INTO SOUTHEAST GEORGIA. CLOUDS WILL
LINGER BUT IT SHOULD BE A BIT WARMER THAN SATURDAY WITH MOST LOCALES
IN THE MID TO UPPER 50S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE LONG TERM PERIOD CONTINUES TO LOOK UNSETTLED AND COMPLEX THROUGH
THE MIDDLE OF NEXT WEEK...LEADING TO A BELOW AVERAGE OVERALL
FORECAST CONFIDENCE CONCERNING THE PERIODS OF HIGHEST RAIN CHANCES.
THE INLAND WEDGE WILL PERSIST AS A WAVE DEVELOPS ALONG THE COAST AND
LIFTS OFF TO THE NORTHEAST THROUGH MONDAY. THIS INLAND WEDGE WILL
LINGER THROUGH TUESDAY BEFORE THE MAIN COLD FRONT AND SURFACE LOW
FINALLY SWEEP THROUGH THE REGION. MODELS STILL DISPLAY NOTABLE
DIFFERENCES IN THE DETAILS IN THIS PERIOD...MAINLY THANKS TO
DISCREPANCIES IN HOW DEEP THE UPPER LOW GETS AND THE OVERALL
AMPLITUDE OF THE MID/UPPER LEVEL TROUGH. MOST AREAS WILL EXPERIENCE
A FEW DAYS OF CLOUD COVER WITH PERIODS OF PRECIPITATION UNTIL THE
COLD FRONT FINALLY SWEEPS THROUGH ON WEDNESDAY. POPS HAVE BEEN KEPT
IN THE CHANCE RANGE FOR NOW...THOUGH IT IS EXPECTED TO PERIODS OF
HIGHER POPS WILL BE NEEDED AS THE FORECAST DETAILS BECOME CLEARER.
TEMPERATURES WILL BE BELOW NORMAL THROUGH MID WEEK.

&&

.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
VFR.

EXTENDED AVIATION OUTLOOK...MVFR CONDITIONS APPEAR LIKELY AS
EARLY AS FRIDAY NIGHT WITH MVFR/IFR CONDITIONS CONTINUING THROUGH
MONDAY AS HIGH PRESSURE BUILDS FROM THE NORTH AND SEVERAL LOW
PRESSURE SYSTEMS MOVE UP THE COAST.

&&

.MARINE...
TONIGHT...WEAK PRESSURE PATTERN WILL PERSIST OVER THE WATERS
TONIGHT. VARIABLE WINDS OF AROUND 5 KT OR LESS WILL EVENTUALLY
BECOME NW/N AFTER MIDNIGHT WITH SPEEDS INCREASING TO 5-10 KT. SEAS
WILL BE 1-2 FEET...HIGHEST IN THE GEORGIA OFFSHORE WATERS.

A HIGH PRESSURE WEDGE WILL STRENGTHEN A BIT THIS WEEKEND WITH AN
UPPER LEVEL DISTURBANCE BRINGING UNSETTLED WEATHER LATE FRIDAY NIGHT
INTO SATURDAY. A LOW PRESSURE SYSTEM OVER THE NORTHERN GULF OF
MEXICO WILL THEN SHIFT NORTHEAST THROUGH THE LOCAL WATERS MONDAY.
ALTHOUGH THERE COULD BE SOME WIND SURGES DEPENDING ON THE STRENGTH
AND TRACK OF THE LOW...CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT
ADVISORY THRESHOLDS THROUGH TUESDAY.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

ST





AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 906 PM CST THU DEC 18 2014

.UPDATE...846 PM CST

WEAK LAKE EFFECT SNOW SHOWERS REMAIN LARGELY OFFSHORE...BUT HAVE
HAD REPORTS OF FLURRIES OR A LIGHT MIST IN LAKE AND COOK COUNTIES OF
ILLINOIS. EXPECT FLURRIES/PATCHY FREEZING DRIZZLE TO REMAIN
POSSIBLE FOR THE EVENING...DIMINISHING QUICKLY OVERNIGHT. NO OTHER
CHANGES TO THE GOING FORECAST FOR THE EVENING.

KMD

&&

.SHORT TERM...
249 PM CST

MAINLY CLOUDY CONDITIONS EXPECTED TO PERSIST THROUGH FRIDAY AS
DIRTY HIGH PRESSURE MOVES ACROSS THE REGION. HIGH RES GUIDANCE IS
SHOWING HINTS OF LAKE EFFECT PRECIP DEVELOPING TONIGHT...THOUGH
FORECAST SOUNDINGS SUGGEST THAT LOW INVERSION HEIGHTS WOULD KEEP
THE THREAT OF ANY MEASURABLE LAKE EFFECT PRECIP VERY LOW. STILL
PLAUSIBLE THAT THERE COULD BE SOME SNOW GRAINS/FLURRIES INTO
NORTHEAST PORTER COUNTY TONIGHT AS LOW LEVEL FLOW VEERS MORE
NORTHERLY.

IZZI

&&

.LONG TERM...
249 PM CST

GOING INTO THE WEEKEND FAIRLY QUIET CONDITIONS EXPECTED. WEAK
NORTHERN STREAM SHORTWAVE WILL PASS MAINLY JUST NORTH OF THE REGION
SATURDAY...BUT MOISTURE/FORCING LOOK TOO LIMITED FOR ANY
PRECIP...THOUGH WAA CLOUDINESS LOOKS TO BE A GOOD BET. ANOTHER WEAK
SHORTWAVE PASSES JUST TO OUR NORTH ON SUNDAY WITH GFS SQUEEZING OUT
SOME LIGHT QPF. ECMWF/WRF-NAM AND PARALLEL GFS KEEP LIGHT PRECIP TO
OUR NORTH...SO HAVE OPTED TO HANG ONTO A DRY FORECAST FOR NOW FOR
SUNDAY BUT WITH PLENTY OF CLOUDINESS OF COURSE.

NEXT WEEK A SIGNIFICANT PATTERN CHANGE IS FORECAST TO TAKE PLACE
ACROSS THE NORTHWESTERN HEMISPHERE WITH SIGNIFICANT LONG WAVE TROUGH
SETTING UP OVER THE UPPER MISSISSIPPI VALLEY AND EVENTUALLY THE
EASTERN CONUS. THE SYSTEM THAT WILL EVENTUALLY CARVE OUT THE DEEP
TROUGH OVER THE REGION IS ACTUALLY THE SAME SIGNIFICANT STORM THAT
JUST AFFECTED JAPAN...SO IT HAS A LONG FAIRLY AND DATA SPARSE REGION
OF THE PACIFIC TO TRAVERSE BEFORE ARRIVING IN OUR AREA. AS IS
TYPICAL WITH LARGE SCALE PATTERN CHANGES...THERE HAVE BEEN
SIGNIFICANT RUN TO RUN MODEL VARIATIONS IN THE HANDLING OF THE
DETAILS OF THIS CYCLONE/DEVELOPING TROUGH AND WOULD ANTICIPATE
FURTHER CHANGES IN LATER MODEL RUNS.

AT THIS POINT...FAIRLY HIGH CONFIDENCE THAT A STORMIER AND
EVENTUALLY COLDER PATTERN WILL SETTLE IN NEXT WEEK. INITIALLY LOOKS
TO BE MORE OF A RAIN/SHOWER EVENT EARLY IN THE WEEK TRANSITIONING TO
MORE FLURRIES/SNOW SHOWERS AS THE UPPER LOW SETTLES IN OVER THE
REGION. LATEST RUNS REALLY ARENT LOOKING TOO FOREBODING FOR
SIGNIFICANT SNOWFALL...BUT AT THIS POINT WOULD REALLY CAUTION ABOUT
LATCHING ONTO ANY ONE SOLUTION AS THERE WILL LIKELY BE MORE MODEL
VARIABILITY IN THE COMING DAYS. CERTAINLY SOME POTENTIAL EXISTS FOR
TRAVEL IMPACTS HEADING INTO THE MIDDLE OF NEXT WEEK.

IZZI

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 03Z...

* MVFR CIGS WILL LIKELY PERSIST THROUGH THE OVERNIGHT HOURS INTO
  FRI MORNING. POSSIBLE DIP TO CIGS ARND 1400FT AGL OVERNIGHT.

BEACHLER

//DISCUSSION...UPDATED 00Z...

WITH HIGH PRESSURE OVERHEAD AND THE LACK OF MIXING...IT IS LIKELY
THAT THE MVFR CIGS THAT HAVE BEEN PERSISTENT ACROSS THE REGION
WILL CONTINUE OVERNIGHT. TO THE NORTH OF THE TAF SITES CIGS HAVE
DIPPED IN A FEW LOCATIONS TO ARND 1400FT AGL. SOME GUIDANCE IS
BEGINNING TO INDICATE THAT CIGS COULD DIP FURTHER AT ORD/MDW
CLOSER TO 1400-1600FTAGL OVERNIGHT. FORTUNATELY WINDS WILL REMAIN
NORTHWESTERLY TO NORTHERLY WITH SPEEDS GENERALLY BETWEEN 4-7KT
THROUGH AT LEAST THE NEXT 18 HOURS POSSIBLY 24 HOURS. CIGS COULD
EVENTUALLY PUSH BACK TO VFR LATE FRI MORNING...BUT THIS IS A LOW
CONFIDENCE BASED ON THE RECENT PAST.

BEACHLER

//ORD AND MDW CONFIDENCE...UPDATED 03Z...

* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS.

BEACHLER

//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z...

* SATURDAY AND SUNDAY...DRY/VFR. LIGHT SOUTH WINDS.
* MONDAY...CHANCE OF RAIN/SNOW. MVFR LIKELY. GUSTY SOUTHERLY WINDS.
* TUESDAY...CHANCE OF RAIN/SNOW. IFR LIKELY. SOUTHWEST WINDS.
* WEDNESDAY...CHANCE OF SNOW. MVFR LIKELY. STRONG/GUST WEST WINDS.

BEACHLER

&&

.MARINE...

230 PM...DEEP LOW PRESSURE IS MOVING NORTHEAST THROUGH NOVA SCOTIA
WHILE A BROAD AREA OF HIGH PRESSURE EXTENDING FROM ONTARIO TO THE
CENTRAL GULF COAST SLOWLY MOVES EAST AND WILL EXTEND FROM QUEBEC
THROUGH THE LOWER MISSISSIPPI VALLEY BY SATURDAY. AS THE HIGH
PRESSURE CONTINUES TO VERY SLOW SPREAD TO THE EAST ACROSS THE
LAKES...WINDS WILL BECOME LIGHT AND VARIABLE FOR A PERIOD FRIDAY
AFTERNOON AND FRIDAY NIGHT. A WEAK TROUGH OF LOW PRESSURE
DEVELOPING OVER THE NORTHERN PLAINS AS THE HIGH BUILDS EAST WILL
SET UP LIGHT SOUTHERLY FLOW OVER THE LAKE. THIS INITIAL TROUGH
WILL MOVE LITTLE THROUGH SATURDAY AND THEN A LOW PRESSURE SYSTEM
IS EXPECTED TO DROP OUT OF THE SOUTHERN CANADIAN ROCKIES BY SUNDAY
EVENING...HELPING TO DEEPEN THE TROUGH INTO A CLOSED LOW. THIS LOW
IS THEN EXPECTED TO TRACK EAST TO WISCONSIN EARLY NEXT WEEK AND AS
THE LOW GETS CLOSER TO THE LAKE...THE SOUTHERLY GRADIENT WILL
STRENGTHEN TO 20 TO 25 KT AS THE LOW DEEPENS AS IT APPROACHES THE
LAKE.

KREIN

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$

VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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  [top]

Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
904 PM CST Thu Dec 18 2014

.UPDATE...
ISSUED AT 900 PM CST THU DEC 18 2014

The surface ridge axis will remain nearly stationary from NW to SE
across Illinois for the next 24 hours or so. That will result in
weak northerly surface winds, and a subsidence inversion to keep
clouds lingering across a majority of the area. A few pockets of
clearing have developed directly under the ridge axis roughly along
the I-74 corridor. Additional low cloud cover borders the clearing
area, and light NW flow in the cloud-bearing layer appears to be
guiding more clouds into the clearing. Forecast soundings do show
a trend toward a thinning of the low level moisture during the day
tomorrow, so the clearing may become more prominent with daytime
mixing and a relaxing of the low level inversion. Will still keep
clouds prevailing in the sky grids overnight, but thin them out
across the north where low clouds have opened up. Fog potential
should be higher in SW IL where the very low clouds have
persisted. Forecast soundings do not support much in the way of
fog in our counties, with the better chances mainly toward
Jacksonville and Taylorville. Low temps may remain slightly warmer
than guidance SW of Lincoln where clouds will be persistent.
Otherwise, low temps looked on track. Made minor updates to the
sky and temps for tonight.

&&

.SHORT TERM...(Tonight)
ISSUED AT 251 PM CST THU DEC 18 2014

Short-wave trough responsible for the light snow earlier today has
sheared out and pushed into Indiana this afternoon, leaving behind
cloudy skies and a few scattered flurries.  With another vigorous
wave noted upstream on water vapor imagery over the Desert
Southwest, short-wave ridging will begin to develop across the
Midwest later tonight into Friday.  This will ensure dry conditions
and perhaps some thinning of the overcast.  20z/2pm visible
satellite imagery already shows some breaks in the cloud cover
developing from the Bloomington area northwestward into Iowa.  As
synoptic subsidence increases in the wake of the departing Indiana
wave, additional breaks will develop further south and east as the
night progresses.  Will maintain mostly cloudy conditions overall,
but think some temporary clearing may occur from time to time.  HRRR
hints at this trend as well.  Meanwhile further west, a low overcast
will prevail across southern Iowa into Missouri.  Will have to keep
an eye on the low clouds and fog to the west, as several high-res
models try to develop fog eastward into the western KILX CWA after
midnight.  Will leave out of the forecast for now, as 18z NAM
forecast soundings show little or no restriction to visibility.  Low
temperatures will be similar to last night in the teens and lower
20s.

&&

.LONG TERM...(Friday through Thursday)
ISSUED AT 251 PM CST THU DEC 18 2014

Morning vort max over northern MO that triggered morning south over
southern 1/2 of CWA has weakened and sheared to the east in
confluent upper flow through the day. Result is the end of light
snow for region in afternoon. Moisture channel data depicts next
wave that was over western AZ at 12z in upper air data, now moved
into eastern AZ. This wave to continue to track east into the
plains, but has weakened and models keep it south of area.

The main system of interest is the digging of the upper trough into
the midwest by late in the weekend. Both GFS and EUR similar in
closing off low into WI by Mon night. Pcpn still develops and
spreads into area Monday, with a brief early chance of a mix of pcpn
type at the onset. Warm advection ahead of the developing surface
low will then keep pcpn rain through Mon and then a light mix in the
northwest sections possible Mon night. Front to move through by
early Tues with cold air following. Therefore a mix of rn/sn in
grids for Tues, changing over to sn on Tues night. Chance of Sn in
the region Wed, but with the upper low in the Great Lakes, pcpn
amounts will be light and only wrap-around light pcpn. Sn amounts
will be light, ending Wed night.

&&

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
ISSUED AT 534 PM CST THU DEC 18 2014

Snow showers and flurries have departed to the east, and VFR cloud
cover has developed across the northern terminals of PIA/BMI under
the surface ridge axis. HRRR and NAM/RUC forecast soundings all
point toward a continuation of at least some cloud cover over the
next 24 hours for all TAF sites. VFR cloud heights are projected
to expand from NE toward the SW tonight, with CMI/DEC ceilings
lifting to VFR. SPI will has the best chance of remaining MVFR
based on their proximity to the IFR/LIFR cloud mass. Confidence
is low on how the cloud cover will play out overnight, but will
default to BKN-OVC conditions throughout the TAF period, and
monitor any holes in the clouds that may develop along under the
ridge axis along the I-74 corridor.

Winds will remain light and variable for the next 24 hours, under
the weak pressure gradient/sfc ridge axis.


&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...Shimon
SHORT TERM...Barnes
LONG TERM...Goetsch
AVIATION...Shimon






AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 539 PM CST THU DEC 18 2014

.SHORT TERM...
249 PM CST

MAINLY CLOUDY CONDITIONS EXPECTED TO PERSIST THROUGH FRIDAY AS
DIRTY HIGH PRESSURE MOVES ACROSS THE REGION. HIGH RES GUIDANCE IS
SHOWING HINTS OF LAKE EFFECT PRECIP DEVELOPING TONIGHT...THOUGH
FORECAST SOUNDINGS SUGGEST THAT LOW INVERSION HEIGHTS WOULD KEEP
THE THREAT OF ANY MEASURABLE LAKE EFFECT PRECIP VERY LOW. STILL
PLAUSIBLE THAT THERE COULD BE SOME SNOW GRAINS/FLURRIES INTO
NORTHEAST PORTER COUNTY TONIGHT AS LOW LEVEL FLOW VEERS MORE
NORTHERLY.

IZZI

&&

.LONG TERM...
249 PM CST

GOING INTO THE WEEKEND FAIRLY QUIET CONDITIONS EXPECTED. WEAK
NORTHERN STREAM SHORTWAVE WILL PASS MAINLY JUST NORTH OF THE REGION
SATURDAY...BUT MOISTURE/FORCING LOOK TOO LIMITED FOR ANY
PRECIP...THOUGH WAA CLOUDINESS LOOKS TO BE A GOOD BET. ANOTHER WEAK
SHORTWAVE PASSES JUST TO OUR NORTH ON SUNDAY WITH GFS SQUEEZING OUT
SOME LIGHT QPF. ECMWF/WRF-NAM AND PARALLEL GFS KEEP LIGHT PRECIP TO
OUR NORTH...SO HAVE OPTED TO HANG ONTO A DRY FORECAST FOR NOW FOR
SUNDAY BUT WITH PLENTY OF CLOUDINESS OF COURSE.

NEXT WEEK A SIGNIFICANT PATTERN CHANGE IS FORECAST TO TAKE PLACE
ACROSS THE NORTHWESTERN HEMISPHERE WITH SIGNIFICANT LONG WAVE TROUGH
SETTING UP OVER THE UPPER MISSISSIPPI VALLEY AND EVENTUALLY THE
EASTERN CONUS. THE SYSTEM THAT WILL EVENTUALLY CARVE OUT THE DEEP
TROUGH OVER THE REGION IS ACTUALLY THE SAME SIGNIFICANT STORM THAT
JUST AFFECTED JAPAN...SO IT HAS A LONG FAIRLY AND DATA SPARSE REGION
OF THE PACIFIC TO TRAVERSE BEFORE ARRIVING IN OUR AREA. AS IS
TYPICAL WITH LARGE SCALE PATTERN CHANGES...THERE HAVE BEEN
SIGNIFICANT RUN TO RUN MODEL VARIATIONS IN THE HANDLING OF THE
DETAILS OF THIS CYCLONE/DEVELOPING TROUGH AND WOULD ANTICIPATE
FURTHER CHANGES IN LATER MODEL RUNS.

AT THIS POINT...FAIRLY HIGH CONFIDENCE THAT A STORMIER AND
EVENTUALLY COLDER PATTERN WILL SETTLE IN NEXT WEEK. INITIALLY LOOKS
TO BE MORE OF A RAIN/SHOWER EVENT EARLY IN THE WEEK TRANSITIONING TO
MORE FLURRIES/SNOW SHOWERS AS THE UPPER LOW SETTLES IN OVER THE
REGION. LATEST RUNS REALLY ARENT LOOKING TOO FOREBODING FOR
SIGNIFICANT SNOWFALL...BUT AT THIS POINT WOULD REALLY CAUTION ABOUT
LATCHING ONTO ANY ONE SOLUTION AS THERE WILL LIKELY BE MORE MODEL
VARIABILITY IN THE COMING DAYS. CERTAINLY SOME POTENTIAL EXISTS FOR
TRAVEL IMPACTS HEADING INTO THE MIDDLE OF NEXT WEEK.

IZZI

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 00Z...

* MVFR CIGS WILL LIKELY PERSIST THROUGH THE OVERNIGHT HOURS INTO
  FRI MORNING. POSSIBLE DIP TO CIGS ARND 1400FT AGL OVERNIGHT.

BEACHLER

//DISCUSSION...UPDATED 00Z...

WITH HIGH PRESSURE OVERHEAD AND THE LACK OF MIXING...IT IS LIKELY
THAT THE MVFR CIGS THAT HAVE BEEN PERSISTENT ACROSS THE REGION
WILL CONTINUE OVERNIGHT. TO THE NORTH OF THE TAF SITES CIGS HAVE
DIPPED IN A FEW LOCATIONS TO ARND 1400FT AGL. SOME GUIDANCE IS
BEGINNING TO INDICATE THAT CIGS COULD DIP FURTHER AT ORD/MDW
CLOSER TO 1400-1600FTAGL OVERNIGHT. FORTUNATELY WINDS WILL REMAIN
NORTHWESTERLY TO NORTHERLY WITH SPEEDS GENERALLY BETWEEN 4-7KT
THROUGH AT LEAST THE NEXT 18 HOURS POSSIBLY 24 HOURS. CIGS COULD
EVENTUALLY PUSH BACK TO VFR LATE FRI MORNING...BUT THIS IS A LOW
CONFIDENCE BASED ON THE RECENT PAST.

BEACHLER


//ORD AND MDW CONFIDENCE...UPDATED 00Z...

* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS.

BEACHLER

//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z...

* SATURDAY AND SUNDAY...DRY/VFR. LIGHT SOUTH WINDS.
* MONDAY...CHANCE OF RAIN/SNOW. MVFR LIKELY. GUSTY SOUTHERLY WINDS.
* TUESDAY...CHANCE OF RAIN/SNOW. IFR LIKELY. SOUTHWEST WINDS.
* WEDNESDAY...CHANCE OF SNOW. MVFR LIKELY. STRONG/GUST WEST WINDS.

BEACHLER

&&

.MARINE...

230 PM...DEEP LOW PRESSURE IS MOVING NORTHEAST THROUGH NOVA SCOTIA
WHILE A BROAD AREA OF HIGH PRESSURE EXTENDING FROM ONTARIO TO THE
CENTRAL GULF COAST SLOWLY MOVES EAST AND WILL EXTEND FROM QUEBEC
THROUGH THE LOWER MISSISSIPPI VALLEY BY SATURDAY. AS THE HIGH
PRESSURE CONTINUES TO VERY SLOW SPREAD TO THE EAST ACROSS THE
LAKES...WINDS WILL BECOME LIGHT AND VARIABLE FOR A PERIOD FRIDAY
AFTERNOON AND FRIDAY NIGHT. A WEAK TROUGH OF LOW PRESSURE
DEVELOPING OVER THE NORTHERN PLAINS AS THE HIGH BUILDS EAST WILL
SET UP LIGHT SOUTHERLY FLOW OVER THE LAKE. THIS INITIAL TROUGH
WILL MOVE LITTLE THROUGH SATURDAY AND THEN A LOW PRESSURE SYSTEM
IS EXPECTED TO DROP OUT OF THE SOUTHERN CANADIAN ROCKIES BY SUNDAY
EVENING...HELPING TO DEEPEN THE TROUGH INTO A CLOSED LOW. THIS LOW
IS THEN EXPECTED TO TRACK EAST TO WISCONSIN EARLY NEXT WEEK AND AS
THE LOW GETS CLOSER TO THE LAKE...THE SOUTHERLY GRADIENT WILL
STRENGTHEN TO 20 TO 25 KT AS THE LOW DEEPENS AS IT APPROACHES THE
LAKE.

KREIN

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$

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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
534 PM CST Thu Dec 18 2014

.SHORT TERM...(Tonight)
ISSUED AT 251 PM CST THU DEC 18 2014

Short-wave trough responsible for the light snow earlier today has
sheared out and pushed into Indiana this afternoon, leaving behind
cloudy skies and a few scattered flurries.  With another vigorous
wave noted upstream on water vapor imagery over the Desert
Southwest, short-wave ridging will begin to develop across the
Midwest later tonight into Friday.  This will ensure dry conditions
and perhaps some thinning of the overcast.  20z/2pm visible
satellite imagery already shows some breaks in the cloud cover
developing from the Bloomington area northwestward into Iowa.  As
synoptic subsidence increases in the wake of the departing Indiana
wave, additional breaks will develop further south and east as the
night progresses.  Will maintain mostly cloudy conditions overall,
but think some temporary clearing may occur from time to time.  HRRR
hints at this trend as well.  Meanwhile further west, a low overcast
will prevail across southern Iowa into Missouri.  Will have to keep
an eye on the low clouds and fog to the west, as several high-res
models try to develop fog eastward into the western KILX CWA after
midnight.  Will leave out of the forecast for now, as 18z NAM
forecast soundings show little or no restriction to visibility.  Low
temperatures will be similar to last night in the teens and lower
20s.

&&

.LONG TERM...(Friday through Thursday)
ISSUED AT 251 PM CST THU DEC 18 2014

Morning vort max over northern MO that triggered morning south over
southern 1/2 of CWA has weakened and sheared to the east in
confluent upper flow through the day. Result is the end of light
snow for region in afternoon. Moisture channel data depicts next
wave that was over western AZ at 12z in upper air data, now moved
into eastern AZ. This wave to continue to track east into the
plains, but has weakened and models keep it south of area.

The main system of interest is the digging of the upper trough into
the midwest by late in the weekend. Both GFS and EUR similar in
closing off low into WI by Mon night. Pcpn still develops and
spreads into area Monday, with a brief early chance of a mix of pcpn
type at the onset. Warm advection ahead of the developing surface
low will then keep pcpn rain through Mon and then a light mix in the
northwest sections possible Mon night. Front to move through by
early Tues with cold air following. Therefore a mix of rn/sn in
grids for Tues, changing over to sn on Tues night. Chance of Sn in
the region Wed, but with the upper low in the Great Lakes, pcpn
amounts will be light and only wrap-around light pcpn. Sn amounts
will be light, ending Wed night.

&&

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
ISSUED AT 534 PM CST THU DEC 18 2014

Snow showers and flurries have departed to the east, and VFR cloud
cover has developed across the northern terminals of PIA/BMI under
the surface ridge axis. HRRR and NAM/RUC forecast soundings all
point toward a continuation of at least some cloud cover over the
next 24 hours for all TAF sites. VFR cloud heights are projected
to expand from NE toward the SW tonight, with CMI/DEC ceilings
lifting to VFR. SPI will has the best chance of remaining MVFR
based on their proximity to the IFR/LIFR cloud mass. Confidence
is low on how the cloud cover will play out overnight, but will
default to BKN-OVC conditions throughout the TAF period, and
monitor any holes in the clouds that may develop along under the
ridge axis along the I-74 corridor.

Winds will remain light and variable for the next 24 hours, under
the weak pressure gradient/sfc ridge axis.

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Barnes
LONG TERM...Goetsch
AVIATION...Shimon






AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 415 PM CST WED DEC 17 2014

.SHORT TERM...
230 PM CST

THROUGH FRIDAY...

RELATIVELY BENIGN WEATHER ON TAP IN THE NEAR TERM UNDER THE
INFLUENCE OF HIGH PRESSURE WHICH WILL REMAIN OVER THE REGION INTO
THE WEEKEND. SURFACE RIDGE EXTENDS FROM MANITOBA INTO THE LOWER
MISSISSIPPI VALLEY THIS AFTERNOON WHILE ALOFT A SHEARED VORT MAX IS
DIGGING SOUTHEAST ACROSS FAR NORTHERN ILLINOIS. SOUNDINGS INDICATE
STEEP LOW LEVEL LAPSE RATES UP TO AROUND 900MB THIS AFTERNOON AND
RADAR IMAGERY DOES SHOW SIGNS OF SOME CONVECTIVE ROLLS WITH VERY
WEAK WIND PARALLEL RETURNS. WITH THESE INGREDIENTS IN PLACE...A FEW
FLURRIES HAVE BEEN NOTED ACROSS THE AREA...BUT NOTHING OF
CONSEQUENCE. ANY FLURRIES SHOULD TAPER BY MID-LATE AFTERNOON AS
INVERSION HEIGHTS BEGIN TO COME DOWN IN RESPONSE TO MODERATE TO
STRONG MID LEVEL HEIGHT RISES BEHIND DEPARTING SHORTWAVE. STRATUS
DECK REMAINS IN PLACE TODAY BUT HAS BEGUN TO THIN AND ERODE NEAR
THE WESTERN COUNTIES. ANY PEAKS OF SUNSHINE TODAY THOUGH ARE
EXPECTED TO BE BRIEF AS MID LEVEL CLOUD COVER INCREASES FROM THE
NORTH AS A WEAK TROUGH EMBEDDED ON THE EASTERN PERIPHERY OF THE
HIGH SAGS SOUTH ACROSS LAKE MICHIGAN...AND FROM THE SOUTHWEST AS
ANOTHER SHORTWAVE TROUGH CURRENTLY LIFTING ACROSS THE PANHANDLES
OF TX/OK PUSHES ACROSS CENTRAL ILLINOIS MIDDAY THURSDAY. PRECIP
WITH THIS SYSTEM IS EXPECTED TO STAY SOUTH OF THE CWA...TAPERING
AS IT OVERRIDES THE SURFACE RIDGE. CLOUD COVER MAY CONTINUE TO
REMAIN LOCKED IN UNDER THE INVERSION FRIDAY...BUT OTHERWISE EXPECT
VERY LIGHT WINDS AND DRY CONDITIONS ON SQUARELY UNDER THE SURFACE
HIGH.

DEUBELBEISS

&&

.LONG TERM...
230 PM CST

FRIDAY NIGHT THROUGH THURSDAY...

HIGH PRESSURE WILL CONTINUE TO SLOWLY SHIFT EAST ACROSS THE REGION
OVER THE WEEKEND WITH RETURN FLOW BRINGING WARMER TEMPERATURES
ESPECIALLY BY SUNDAY. MEANWHILE...THE PATTERN IS PROGGED TO BEGIN
AMPLIFYING BY LATE IN THE WEEKEND AS LONGWAVE TROUGH DEEPENS ACROSS
THE MID SECTION OF THE COUNTRY DOWNSTREAM OF A BUILDING RIDGE ALONG
THE WEST COAST. THE JET STREAM WILL DIVE TOWARDS THE GULF STATES BY
TUESDAY WITH SURFACE LOW DEEPENING IN RESPONSE EARLY NEXT WEEK.
THERE REMAIN SIGNIFICANT DIFFERENCES AS WELL AS RUN-TO-RUN
VARIABILITY IN THE TIMING AND TRACK OF THE LOW AS IT LIFTS ACROSS
THE MIDWEST MIDWEEK...WITH COMPLICATIONS AS THE MODELS DEAL WITH
PHASING THE SOUTHERN LOW WITH A CLIPPER LIKE SYSTEM. WILL
CERTAINLY HAVE TO KEEP AN EYE ON THE POTENTIAL FOR ACCUMULATING
SNOW TUESDAY INTO WEDNESDAY OVER THE NEXT SEVERAL DAYS AS MODELS
HOPEFULLY BEGIN TO HONE IN ON A SOLUTION. A RETURN TO BELOW NORMAL
CONDITIONS SEEMS LIKELY FOR THE LATTER HALF OF THE WEEK.

DEUBELBEISS

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 22Z...

* MVFR CEILING TRENDS AND POSSIBLE SCATTERING.

* WIND TRENDS...GUSTINESS TODAY AND VARIABLE LATE TONIGHT.

LENNING

//DISCUSSION...UPDATED 18Z...

CEILINGS ARE HANGING IN THE MVFR RANGE BUT SHOWING SIGNS OF
SCATTERING OUT IN AREAS WEST OF THE ORD/MDW TERMINALS. GIVEN THE
PERSISTENCE OF THIS CLOUD SHIELD IT IS HARD TO PUSH THE CLEARING
INTO THE AREA BEFORE WE ACTUALLY SEE IT HAPPENING...SO FOR NOW
WILL MAINTAIN CURRENT TRENDS INTO THE OVERNIGHT HOURS. WINDS
REMAIN WESTERLY TO NORTHWESTERLY FOR MOST OF THE PERIOD...BUT BY
TOMORROW A WEAKENING PRESSURE GRADIENT MAY ALLOW WINDS TO GO
VARIABLE FOR A TIME...THOUGH LIKELY CONTINUE TO FAVOR A WESTERLY
COMPONENT.

LENNING

//ORD AND MDW CONFIDENCE...UPDATED 22Z...

* MEDIUM CONFIDENCE IN CEILING TRENDS.

* HIGHER CONFIDENCE IN WIND TRENDS.

LENNING

//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...

* THURSDAY NIGHT THROUGH SATURDAY...DRY/VFR. LIGHT/VRB WINDS.
* SUNDAY...DRY. MVFR POSSIBLE. SOUTH WINDS.
* MONDAY...CHANCE OF RAIN. MVFR LIKELY. GUSTY SOUTH WINDS.
* TUESDAY...CHANCE OF RAIN. IFR POSSIBLE. SOUTHWEST WINDS.

&&

.MARINE...
210 PM CST

THE LOW PRESSURE THAT PASSED THROUGH THE GREAT LAKES REGION OVER THE
PAST COUPLE DAYS IS IN THE PROCESS OF MERGING WITH ANOTHER LOW OVER
THE NEW ENGLAND COAST.  THIS LOW WILL GRADUALLY DEEPEN AND SLOWLY
MOVE NORTH ALONG THE NEW ENGLAND COAST AS HIGH PRESSURE SPREADS FROM
THE NORTHERN PLAINS AND ACROSS THE WESTERN GREAT LAKES BY THURSDAY
MORNING.  WINDS ARE SLOWLY SUBSIDING OVER THE LAKE...BUT A SECONDARY
TROUGH AND SURGE OF COOLER AIR MOVING DOWN THE LAKE THIS AFTERNOON
AND EVENING WILL KEEP RELATIVELY BRISK NLY-NLWY WINDS OVER THE LAKE
THROUGH THE NIGHT TONIGHT.  WINDS SHOULD WEAKEN TO THE 10-15KT RANGE
THURSDAY NIGHT AND FRIDAY AS THE HIGH GRADUALLY SPREADS EAST...WHILE
MAINTAINING A NLY DIRECTION.  THE HIGH WILL SPREAD ACROSS LAKE
MICHIGAN THURSDAY NIGHT AND FRIDAY...LEADING TO MORE LGT/VRBL WINDS
OVER THE LAKE.  HIGH PRESSURE WILL VERY SLOWLY SPREAD EWD...BUT
STILL CONTROLLING FLOW OVER THE LAKE...KEEPING WINDS GENERALLY LIGHT
AND VARIABLE INTO THE WEEKEND.  BY SUNDAY...THE HIGH WILL FINALLY
PUSH EAST OF LAKE MICHIGAN AS A TROUGH OF LOW PRESSURE DEVELOPS OVER
THE NORTHERN PLAINS.  THIS WILL SET UP INCREASING SLY FLOW OVER THE
LAKE BY SUNDAY.  A DEVELOPING LOW IS EXPECTED TO TRACK ACROSS THE
NRN PLAINS SUNDAY NIGHT AND MONDAY...REACHING THE MIDDLE MISSISSIPPI
VALLEY BY TUESDAY.  THIS WILL KEEP GENERALLY SOUTHERLY WINDS OVER
THE LAKE THROUGH EARLY NEXT WEEK.

KREIN

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 10 AM THURSDAY.

&&

$$

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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
247 PM CST Wed Dec 17 2014

.SHORT TERM...(Tonight)
ISSUED AT 245 PM CST WED DEC 17 2014

19z/1pm satellite imagery continues to show overcast conditions
across much of central Illinois: however, the clouds are beginning
to erode northwest of the Illinois River.  While HRRR guidance has
not been particularly useful in the short-term, satellite trends
suggest skies will partially clear across all but the far E/NE KILX
CWA by early evening.  After a period of mostly clear skies early
tonight, clouds will once again begin increasing in advance of the
next storm system, which is currently evident on water vapor imagery
over west Texas.  Quite a bit of precip and even some thunder is
occurring ahead of this wave over Oklahoma/Texas: however, it is
expected to weaken as it lifts northeastward into the region on
Thursday.  It will also be coming into a dry airmass beneath a
prevailing surface ridge axis.  Forecast soundings show gradual
moistening from the top-down later tonight, but the lowest levels
below 850mb will remain quite dry through 12z.  As a result, have
maintained a dry forecast through the overnight hours.  Due to the
initially clear skies and low dewpoints, have gone a couple of
degrees below MAV guidance for lows tonight, with readings dropping
into the teens and lower 20s.


&&

.LONG TERM...(Thursday through Wednesday)
ISSUED AT 245 PM CST WED DEC 17 2014

Upper flow will be zonal for next few days, with weak waves moving
east through flow. Moisture channel data and upper air shows initial
wave to affect region over NM this morning. This system to
continue tracking to the northeast, pushing some overrunning pcpn
into MO and southern 1/2 of IL for late tonight into Thursday. Weak
vort lobe and isentropic lift to be enough to move the light snow
into southern 1/2 of CWA in the morning, but wave moving fast enough
to only affect the morning. Mainly less than half inch.

Next wave to move into region for Friday night and Saturday morning
and the area of lift with this one is farther south, mainly over
southeast cwa. Again, some light snow possible.

Upper flow starts to change on late in weekend and by Monday, flow
is northwest. Digging upper trough over Great Lakes with upper low
closing off by Monday night. This will bring some initial pcpn into
the region ahead of cold front that moves through Tuesday.
Temperatures however, are only cold enough for possible mixture
until post frontal on Tuesday night and Wednesday. Therefore no snow
accumulation. However by tues night to Wed, only minor vort lobes
rotating around the closed upper low in the cold air, so chance of
light snow accumulations only.


&&

.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
ISSUED AT 1203 PM CST WED DEC 17 2014

MVFR ceilings will prevail at the central Illinois terminals for
the next few hours before clearing gradually develops from west to
east across the area. 1730z visible satellite imagery shows
clearing beginning to work into the northwest KILX CWA around
Galesburg, and based on timing tools, this should reach KPIA by
around 21/22z. Will continue to monitor satellite to see if clouds
can erode faster, but for now will remain pessimistic. Clouds will
hold firm further east at KCMI until early evening when forecast
soundings finally show low-level drying. After a brief period of
mostly clear skies tonight, the next approaching system will
spread clouds back into the area on Thursday. Forecast soundings
suggest VFR ceilings developing across central Illinois between 11z
and 14z. May see enough moistening of the profile to produce light
snow at KSPI after 15z, but dry conditions should prevail
elsewhere.


&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Barnes
LONG TERM...Goetsch
AVIATION...Barnes






AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 1212 PM CST WED DEC 17 2014

.SHORT TERM...
315 AM CST

THROUGH THURSDAY...

THE SYSTEM THAT BROUGHT A RETURN TO MORE SEASONAL TEMPERATURES IS
NOW CENTERED OVER THE EASTERN GREAT LAKES. THIS UPPER LOW IS
ROTATING AROUND A NOW DEEPER BUT SHEARING UPPER LOW CENTERED OVER
MINNESOTA AND WISCONSIN EARLY THIS MORNING. AT THE LOW-LEVELS THIS
SLOW MOVING PATTERN IS HELPING KEEP COLD AIR ADVECTION IN PLACE.
WHILE NOT PARTICULARLY STRONG FOR DECEMBER...THIS ADVECTION WITHIN
CYCLONIC FLOW HAS HELPED KEEP THE CLOUDS AND EVEN SOME FLURRIES.
EARLY MORNING SATELLITE IMAGERY INDICATES THE BACK EDGE CLEARING
FROM MINNEAPOLIS TO DES MOINES AND MAKING LITTLE PROGRESS. UPSTREAM
00Z SOUNDINGS AND CURRENT ACARS DATA FROM RFD INDICATE THE MOISTURE
DEPTH IS VERY SHALLOW. SO CERTAINLY THERE IS POTENTIAL TO SCATTER
FROM WEST TO EAST TODAY AND HIGH RESOLUTION GUIDANCE AND CONDENSATE
FIELDS DO PAINT THIS PICTURE AS WELL. GIVEN FURTHER STRENGTHENING OF
THE SUBSIDENCE INVERSION ON FORECAST SOUNDINGS ACROSS NORTH CENTRAL
ILLINOIS...HAVE GONE WITH FORECAST SCATTERING THERE BY EARLY
AFTERNOON. A LITTLE MORE TRICKY TOWARD CHICAGO AND NORTHWEST INDIANA
AND HAVE FAVORED THAT AREA REMAINING AT LEAST MOSTLY CLOUDY THROUGH
MUCH OF TODAY.

HIGH TEMPERATURES TODAY LOOK TO BE THEIR COOLEST IN ABOUT A WEEK
WITH UPPER 20S AND LOWER 30S SUPPORTED GIVEN LITTLE DIURNAL CLIMB
EXPECTED. THIS IS JUST A TAD BELOW MID-DECEMBER NORMALS. AS FOR
TONIGHT...LIKE A SONG ON REPEAT...THE CONFIDENCE ON CLOUDS ONCE
AGAIN IS LOW. WHILE SOME AREAS MAY SEE NOT MUCH FOR CLOUDS IN THE
EVENING...HIGH CLOUDS LOOK TO MOVE NORTHWARD OVER THE AREA LATE
TONIGHT. WITH LIGHTER WINDS THE POTENTIAL EXISTS FOR TEMPERATURES TO
DROP INTO THE LOWER TO MID TEENS IN OUTLYING AREAS.

THE GREAT LAKES BROAD UPPER LOW WILL MOVE EAST ON THURSDAY WEAKENING
THE CONFLUENT UPPER FLOW OVER THE FORECAST AREA. THIS WILL HELP A
SOUTHERN STREAM SYSTEM...CENTERED IN EASTERN ARIZONA EARLY THIS
MORNING...TO MAKE SOME INROADS WITH MID-LEVEL WARM AND MOIST
ADVECTION UP TO AT LEAST CENTRAL ILLINOIS AND INDIANA. THIS SHOULD
BRING CLOUDS TO MUCH OF THE AREA. HAVE NOT INCLUDED ANY LIGHT SNOW
IN THE FAR SOUTHERN AREA AT THIS TIME AS THE SUPPORT FOR LIFT STAYS
JUST SOUTH ON MOST GUIDANCE SOLUTIONS.

MTF

&&

.LONG TERM...
315 AM CST

FRIDAY THROUGH TUESDAY...

SURFACE HIGH PRESSURE RIDGING BASICALLY MAINTAINS ITSELF OVER THE
AREA THROUGH THE WEEKEND. THE UPPER PATTERN REMAINS SOMEWHAT SPLIT
WITH A SYSTEM LIKELY ENTIRELY PASSING TO OUR SOUTHEAST ON SATURDAY.
A NORTHERN STREAM UPPER LOW IS FORECAST TO BRING SOME PACIFIC
MOISTURE...MAINLY ALOFT...OVER THE AREA SATURDAY EVENING/OVERNIGHT.
LIFT IS WEAK AND MAINLY FOCUSED NORTH SO DO NOT HAVE ANY
POPS...HOWEVER HAVE INCREASED CLOUD COVER IN THE FORECAST AND WITH
THAT FORECAST MINS ON SATURDAY NIGHT.

THE WEATHER PATTERN ACROSS THE CENTRAL CONUS HAS BEEN CONSISTENTLY
FORECAST BY LONG RANGE MODELS AND ENSEMBLES TO BECOME MORE AMPLIFIED
DURING NEXT WEEK. JUST LOOKING ON HEMISPHERIC WATER VAPOR THIS
MORNING...MULTIPLE SYSTEMS ON ACTIVE JET ARE SEEN ACROSS THE
NORTHERN PACIFIC...SO A PATTERN SHIFT SEEMS LIKELY. THE CONSENSUS OF
GUIDANCE FAVORS AN ANOMALOUS SURFACE REFLECTION TO DEVELOP ACROSS
THE MIDWEST MONDAY INTO TUESDAY...THOUGH AS ONE CAN EXPECT THERE ARE
LARGE DIFFERENCES IN PLACEMENT.  HAVE INCREASED FORECAST POPS IN
LINE WITH A SMART GUIDANCE BLEND. GIVEN A CONSENSUS PLACEMENT
THOUGH...IT WOULD SEEM PROFILES WOULD BE MILD ENOUGH FOR MAINLY RAIN
AT FIRST IN OUR AREA. CERTAINLY THIS BECOMES A LOT MORE IN QUESTION
AS THE TROUGH FURTHER AMPLIFIES SUCH AS MODELS SUGGEST INTO
TUESDAY AND CHRISTMAS EVE.

MTF

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 18Z...

* MVFR CEILING TRENDS AND POSSIBLE SCATTERING.

* WIND TRENDS...GUSTINESS TODAY AND VARIABLE LATE TONIGHT.

LENNING

//DISCUSSION...UPDATED 18Z...

CEILINGS ARE HANGING IN THE MVFR RANGE BUT SHOWING SIGNS OF
SCATTERING OUT IN AREAS WEST OF THE ORD/MDW TERMINALS. GIVEN THE
PERSISTENCE OF THIS COULD SHIELD IT IS HARD TO PUSH THE CLEARING
INTO THE AREA BEFORE WE ACTUALLY SEE IT HAPPENING...SO FOR NOW WILL
MAINTAIN CURRENT TRENDS INTO THE OVERNIGHT HOURS. WINDS REMAIN
WESTERLY TO NORTHWESTERLY FOR MOST OF THE PERIOD...BUT BY TOMORROW
A WEAKENING PRESSURE GRADIENT MAY ALLOW WINDS TO GO VARIABLE FOR A
TIME...BUT LIKELY CONTINUE TO FAVOR A WESTERLY COMPONENT.

LENNING


//ORD AND MDW CONFIDENCE...UPDATED 18Z...

* MEDIUM CONFIDENCE IN CEILING TRENDS.

* HIGHER CONFIDENCE IN WIND TRENDS.

LENNING

//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...

* THURSDAY NIGHT THROUGH SATURDAY...DRY/VFR. LIGHT/VRB WINDS.
* SUNDAY...DRY. MVFR POSSIBLE. SOUTH WINDS.
* MONDAY...CHANCE OF RAIN. MVFR LIKELY. GUSTY SOUTH WINDS.
* TUESDAY...CHANCE OF RAIN. IFR POSSIBLE. SOUTHWEST WINDS.

&&

.MARINE...

210 AM...LOW PRESSURE NEAR LAKE ONTARIO WILL MOVE EAST AND BE
ABSORBED BY LOW PRESSURE MOVING NORTH ALONG THE NEW ENGLAND COAST.
THIS LOW WILL THEN SLOWLY LIFT NORTHEAST AND DEEPEN OVER THE NEXT
FEW DAYS. A LARGE AREA OF HIGH PRESSURE EXTENDING FROM MANITOBA
INTO THE CENTRAL PLAINS WILL SLOWLY BUILD EAST ACROSS THE LAKES
REGION THURSDAY AND FRIDAY. NORTHWEST WINDS TO 30 KTS IN BETWEEN
THESE TWO SYSTEMS WILL GRADUALLY DIMINISH TONIGHT INTO THURSDAY.
AS THE HIGH DRIFTS ACROSS THE LAKES REGION...THERE WILL BE A
PERIOD OF LIGHT PERHAPS EVEN CALM WINDS FRIDAY NIGHT INTO SATURDAY
NIGHT UNTIL THE HIGH MOVES EAST SUNDAY AND SUNDAY NIGHT AND THE
FLOW TURNS BACK SOUTHERLY. CMS

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 10 AM THURSDAY.

&&

$$

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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1203 PM CST Wed Dec 17 2014

.UPDATE...
ISSUED AT 950 AM CST WED DEC 17 2014

Clouds continue to blanket central and southeast Illinois this
morning, thanks to low-level moisture trapped beneath a subsidence
inversion at around 900mb. Enough synoptic lift is being generated
by a short-wave trough sinking southward through Wisconsin to trigger
a few snow flurries across the area. Radar imagery has shown some
weak echoes from near Peoria southeastward along the I-74
corridor, with both KBMI and KCMI reporting flurries at some
point this morning. Have updated the forecast to include scattered
flurries across the northern KILX CWA accordingly. Main question
of the day will be whether or not any clearing will occur. Latest
visible satellite imagery shows clearing across much of Iowa, as
well as central/southern Missouri. Based on timing tools, skies
will clear across the Illinois River Valley this afternoon, then
toward the I-55 corridor by late afternoon/early evening. Have
adjusted sky grids to better reflect current trends, featuring
partly sunny skies across the west this afternoon and continued
overcast conditions further east toward the Indiana border.

&&

.SHORT TERM...(Today)
ISSUED AT 310 AM CST WED DEC 17 2014

A north-south oriented elongated high pressure ridge will edge
eastward toward Illinois today bringing with it a much lighter
surface pressure gradient and subsidence aloft. The result will be
wind speeds and gusts tapering off throughout the day as well as
thinning low cloud cover. Seasonably cold temperatures that arrived
after yesterday`s cold front will continue, with highs today only
around the freezing mark, just a few degrees below normal.
Although cloud cover will thin out through the day, current
indications are that the GFS and HRRR models are too aggressive in
clearing out low level moisture trapped below an inversion based
just below 900 mb. Forecast cloud cover is based more in line with
the NAM which keeps a saturated layer through the early part of
the day, slowly thinning through the afternoon. Meanwhile, periods
of high cloud cover will be arriving in the afternoon as well.

Also watching a band of snow flurries moving southward through Iowa
this morning. This looks as if it will remain west of the central IL
forecast area before the disturbance responsible for it ejects
eastward. This could move through portions of central IL later this
morning, but would be of very little consequence and is a fairly low
probability at this point.

&&

.LONG TERM...(Tonight through Tuesday)
ISSUED AT 310 AM CST WED DEC 17 2014

Upper wave currently pushing through Arizona on track to reach the
southern Plains tonight, before dampening out somewhat as it moves
across Missouri. Forecast soundings off most of the models are
showing the column moistening from the top down overnight, but very
dry air lingers just past sunrise below 800 mb. A short period of
isentropic lift on the 305K plane will move through central Illinois
Thursday morning, coinciding with the moistening of the lower
layers, resulting in a period of light snow across the southwestern
CWA during the morning. Current thinking is only a few tenths from
Rushville through Springfield to the Effingham/Flora areas. The
soundings further northeast toward Peoria and Bloomington generally
never really moisten the lower levels (except for the NAM), and will
keep those areas dry on Thursday.

Model trends for the Friday night/Saturday system continue to shift
more to the south, as the next deepening wave tracks into the lower
Mississippi Valley. Have limited the PoP`s for Friday night and
Saturday morning to areas south of I-70, where accumulations look to
be less than an inch. The ECMWF tries to draw some of the moisture
northward Saturday morning as a separate wave in the northern stream
swings into the Great Lakes region, so have kept some slight chances
during the morning across east central Illinois.

Active period setting up next week, as a broad long wave trough digs
southward through the central U.S. Some timing differences as to the
depth of this wave, with the ECMWF and parallel GFS cutting off a
low over southeast South Dakota and drifting it east, while the
operational GFS waits until mid week to cut off a broad low over the
Midwest. Both solutions yield precipitation as a storm system
organizes just to our northwest. Have continued to concentrate the
precip chances Monday night into Tuesday, mostly rain but perhaps
some snow mixed in across the far north. Will need to watch the
evolution of this closely, with the pre-holiday travel rush
beginning around this time.

&&

.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
ISSUED AT 1203 PM CST WED DEC 17 2014

MVFR ceilings will prevail at the central Illinois terminals for
the next few hours before clearing gradually develops from west to
east across the area. 1730z visible satellite imagery shows
clearing beginning to work into the northwest KILX CWA around
Galesburg, and based on timing tools, this should reach KPIA by
around 21/22z. Will continue to monitor satellite to see if clouds
can erode faster, but for now will remain pessimistic. Clouds will
hold firm further east at KCMI until early evening when forecast
soundings finally show low-level drying. After a brief period of
mostly clear skies tonight, the next approaching system will
spread clouds back into the area on Thursday. Forecast soundings
suggest VFR ceilings developing across central Illinois between 11z
and 14z. May see enough moistening of the profile to produce light
snow at KSPI after 15z, but dry conditions should prevail
elsewhere.

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...Barnes
SHORT TERM...Onton
LONG TERM...Geelhart
AVIATION...Barnes







AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 1003 AM CST WED DEC 17 2014

.SHORT TERM...
315 AM CST

THROUGH THURSDAY...

THE SYSTEM THAT BROUGHT A RETURN TO MORE SEASONAL TEMPERATURES IS
NOW CENTERED OVER THE EASTERN GREAT LAKES. THIS UPPER LOW IS
ROTATING AROUND A NOW DEEPER BUT SHEARING UPPER LOW CENTERED OVER
MINNESOTA AND WISCONSIN EARLY THIS MORNING. AT THE LOW-LEVELS THIS
SLOW MOVING PATTERN IS HELPING KEEP COLD AIR ADVECTION IN PLACE.
WHILE NOT PARTICULARLY STRONG FOR DECEMBER...THIS ADVECTION WITHIN
CYCLONIC FLOW HAS HELPED KEEP THE CLOUDS AND EVEN SOME FLURRIES.
EARLY MORNING SATELLITE IMAGERY INDICATES THE BACK EDGE CLEARING
FROM MINNEAPOLIS TO DES MOINES AND MAKING LITTLE PROGRESS. UPSTREAM
00Z SOUNDINGS AND CURRENT ACARS DATA FROM RFD INDICATE THE MOISTURE
DEPTH IS VERY SHALLOW. SO CERTAINLY THERE IS POTENTIAL TO SCATTER
FROM WEST TO EAST TODAY AND HIGH RESOLUTION GUIDANCE AND CONDENSATE
FIELDS DO PAINT THIS PICTURE AS WELL. GIVEN FURTHER STRENGTHENING OF
THE SUBSIDENCE INVERSION ON FORECAST SOUNDINGS ACROSS NORTH CENTRAL
ILLINOIS...HAVE GONE WITH FORECAST SCATTERING THERE BY EARLY
AFTERNOON. A LITTLE MORE TRICKY TOWARD CHICAGO AND NORTHWEST INDIANA
AND HAVE FAVORED THAT AREA REMAINING AT LEAST MOSTLY CLOUDY THROUGH
MUCH OF TODAY.

HIGH TEMPERATURES TODAY LOOK TO BE THEIR COOLEST IN ABOUT A WEEK
WITH UPPER 20S AND LOWER 30S SUPPORTED GIVEN LITTLE DIURNAL CLIMB
EXPECTED. THIS IS JUST A TAD BELOW MID-DECEMBER NORMALS. AS FOR
TONIGHT...LIKE A SONG ON REPEAT...THE CONFIDENCE ON CLOUDS ONCE
AGAIN IS LOW. WHILE SOME AREAS MAY SEE NOT MUCH FOR CLOUDS IN THE
EVENING...HIGH CLOUDS LOOK TO MOVE NORTHWARD OVER THE AREA LATE
TONIGHT. WITH LIGHTER WINDS THE POTENTIAL EXISTS FOR TEMPERATURES TO
DROP INTO THE LOWER TO MID TEENS IN OUTLYING AREAS.

THE GREAT LAKES BROAD UPPER LOW WILL MOVE EAST ON THURSDAY WEAKENING
THE CONFLUENT UPPER FLOW OVER THE FORECAST AREA. THIS WILL HELP A
SOUTHERN STREAM SYSTEM...CENTERED IN EASTERN ARIZONA EARLY THIS
MORNING...TO MAKE SOME INROADS WITH MID-LEVEL WARM AND MOIST
ADVECTION UP TO AT LEAST CENTRAL ILLINOIS AND INDIANA. THIS SHOULD
BRING CLOUDS TO MUCH OF THE AREA. HAVE NOT INCLUDED ANY LIGHT SNOW
IN THE FAR SOUTHERN AREA AT THIS TIME AS THE SUPPORT FOR LIFT STAYS
JUST SOUTH ON MOST GUIDANCE SOLUTIONS.

MTF

&&

.LONG TERM...
315 AM CST

FRIDAY THROUGH TUESDAY...

SURFACE HIGH PRESSURE RIDGING BASICALLY MAINTAINS ITSELF OVER THE
AREA THROUGH THE WEEKEND. THE UPPER PATTERN REMAINS SOMEWHAT SPLIT
WITH A SYSTEM LIKELY ENTIRELY PASSING TO OUR SOUTHEAST ON SATURDAY.
A NORTHERN STREAM UPPER LOW IS FORECAST TO BRING SOME PACIFIC
MOISTURE...MAINLY ALOFT...OVER THE AREA SATURDAY EVENING/OVERNIGHT.
LIFT IS WEAK AND MAINLY FOCUSED NORTH SO DO NOT HAVE ANY
POPS...HOWEVER HAVE INCREASED CLOUD COVER IN THE FORECAST AND WITH
THAT FORECAST MINS ON SATURDAY NIGHT.

THE WEATHER PATTERN ACROSS THE CENTRAL CONUS HAS BEEN CONSISTENTLY
FORECAST BY LONG RANGE MODELS AND ENSEMBLES TO BECOME MORE AMPLIFIED
DURING NEXT WEEK. JUST LOOKING ON HEMISPHERIC WATER VAPOR THIS
MORNING...MULTIPLE SYSTEMS ON ACTIVE JET ARE SEEN ACROSS THE
NORTHERN PACIFIC...SO A PATTERN SHIFT SEEMS LIKELY. THE CONSENSUS OF
GUIDANCE FAVORS AN ANOMALOUS SURFACE REFLECTION TO DEVELOP ACROSS
THE MIDWEST MONDAY INTO TUESDAY...THOUGH AS ONE CAN EXPECT THERE ARE
LARGE DIFFERENCES IN PLACEMENT.  HAVE INCREASED FORECAST POPS IN
LINE WITH A SMART GUIDANCE BLEND. GIVEN A CONSENSUS PLACEMENT
THOUGH...IT WOULD SEEM PROFILES WOULD BE MILD ENOUGH FOR MAINLY RAIN
AT FIRST IN OUR AREA. CERTAINLY THIS BECOMES A LOT MORE IN QUESTION
AS THE TROUGH FURTHER AMPLIFIES SUCH AS MODELS SUGGEST INTO
TUESDAY AND CHRISTMAS EVE.

MTF

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 16Z...

* MVFR CIGS THRU TONIGHT.
* GUSTY WEST/NORTHWEST WINDS THRU EARLY AFTERNOON.

LENNING/CMS

//DISCUSSION...UPDATED 12Z...

MAIN FORECAST CONCERN WILL BE WHEN MVFR CIGS WILL SCATTER OUT.
BACK EDGE STILL ACROSS CENTRAL IA AND EASTERN MN AND MAKING VERY
SLOW PROGRESS TO THE SOUTHEAST. FORECAST SOUNDINGS STILL SUGGEST
INVERSION ALOFT WILL BE STRONG ENOUGH TO TRAP THESE CLOUDS FOR
MOST OF THE DAYLIGHT HOURS AND POSSIBLY INTO THIS EVENING. SO
OPTED TO MAINTAIN MVFR CIGS INTO TONIGHT WITH SOME SCATTERING OR
CLEARING POSSIBLE OVERNIGHT...WHICH WILL LIKELY OCCUR FIRST AT RFD
AND POSSIBLY AS EARLY AS THIS EVENING.

A FEW FLURRIES WILL BE POSSIBLE THIS MORNING...BUT NO RESTRICTIONS
TO VIS EXPECTED.

WEST/NORTHWEST WINDS HAVE DIMINISHED SOME DURING THE EARLY MORNING
HOURS AND EXPECT THEM TO REMAIN GENERALLY STEADY INTO THIS
AFTERNOON...IN THE 10-15KT RANGE WITH GUSTS INTO THE MID/UPPER
TEENS. WINDS WILL SLOWLY DIMINISH THIS AFTERNOON THROUGH TONIGHT
AS THE GRADIENT SLOWLY WEAKENS. CMS

//ORD AND MDW CONFIDENCE...UPDATED 16Z...

* MEDIUM FOR CIGS THRU THE PERIOD.
* HIGH FOR WINDS THRU THE PERIOD.

LENNING/CMS

//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...

* THURSDAY NIGHT THROUGH SATURDAY...DRY/VFR. LIGHT/VRB WINDS.
* SUNDAY...DRY. MVFR POSSIBLE. SOUTH WINDS.
* MONDAY...CHANCE OF RAIN. MVFR LIKELY. GUSTY SOUTH WINDS.
* TUESDAY...CHANCE OF RAIN. IFR POSSIBLE. SOUTHWEST WINDS.

&&

.MARINE...

210 AM...LOW PRESSURE NEAR LAKE ONTARIO WILL MOVE EAST AND BE
ABSORBED BY LOW PRESSURE MOVING NORTH ALONG THE NEW ENGLAND COAST.
THIS LOW WILL THEN SLOWLY LIFT NORTHEAST AND DEEPEN OVER THE NEXT
FEW DAYS. A LARGE AREA OF HIGH PRESSURE EXTENDING FROM MANITOBA
INTO THE CENTRAL PLAINS WILL SLOWLY BUILD EAST ACROSS THE LAKES
REGION THURSDAY AND FRIDAY. NORTHWEST WINDS TO 30 KTS IN BETWEEN
THESE TWO SYSTEMS WILL GRADUALLY DIMINISH TONIGHT INTO THURSDAY.
AS THE HIGH DRIFTS ACROSS THE LAKES REGION...THERE WILL BE A
PERIOD OF LIGHT PERHAPS EVEN CALM WINDS FRIDAY NIGHT INTO SATURDAY
NIGHT UNTIL THE HIGH MOVES EAST SUNDAY AND SUNDAY NIGHT AND THE
FLOW TURNS BACK SOUTHERLY. CMS

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 10 AM THURSDAY.

&&

$$

VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO






Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
950 AM CST Wed Dec 17 2014

.UPDATE...
ISSUED AT 950 AM CST WED DEC 17 2014

Clouds continue to blanket central and southeast Illinois this
morning, thanks to low-level moisture trapped beneath a subsidence
inversion at around 900mb. Enough synoptic lift is being generated
by a short-wave trough sinking southward through Wisconsin to trigger
a few snow flurries across the area. Radar imagery has shown some
weak echoes from near Peoria southeastward along the I-74
corridor, with both KBMI and KCMI reporting flurries at some
point this morning. Have updated the forecast to include scattered
flurries across the northern KILX CWA accordingly. Main question
of the day will be whether or not any clearing will occur. Latest
visible satellite imagery shows clearing across much of Iowa, as
well as central/southern Missouri. Based on timing tools, skies
will clear across the Illinois River Valley this afternoon, then
toward the I-55 corridor by late afternoon/early evening. Have
adjusted sky grids to better reflect current trends, featuring
partly sunny skies across the west this afternoon and continued
overcast conditions further east toward the Indiana border.

&&

.SHORT TERM...(Today)
ISSUED AT 310 AM CST WED DEC 17 2014

A north-south oriented elongated high pressure ridge will edge
eastward toward Illinois today bringing with it a much lighter
surface pressure gradient and subsidence aloft. The result will be
wind speeds and gusts tapering off throughout the day as well as
thinning low cloud cover. Seasonably cold temperatures that arrived
after yesterday`s cold front will continue, with highs today only
around the freezing mark, just a few degrees below normal.
Although cloud cover will thin out through the day, current
indications are that the GFS and HRRR models are too aggressive in
clearing out low level moisture trapped below an inversion based
just below 900 mb. Forecast cloud cover is based more in line with
the NAM which keeps a saturated layer through the early part of
the day, slowly thinning through the afternoon. Meanwhile, periods
of high cloud cover will be arriving in the afternoon as well.

Also watching a band of snow flurries moving southward through Iowa
this morning. This looks as if it will remain west of the central IL
forecast area before the disturbance responsible for it ejects
eastward. This could move through portions of central IL later this
morning, but would be of very little consequence and is a fairly low
probability at this point.

&&

.LONG TERM...(Tonight through Tuesday)
ISSUED AT 310 AM CST WED DEC 17 2014

Upper wave currently pushing through Arizona on track to reach the
southern Plains tonight, before dampening out somewhat as it moves
across Missouri. Forecast soundings off most of the models are
showing the column moistening from the top down overnight, but very
dry air lingers just past sunrise below 800 mb. A short period of
isentropic lift on the 305K plane will move through central Illinois
Thursday morning, coinciding with the moistening of the lower
layers, resulting in a period of light snow across the southwestern
CWA during the morning. Current thinking is only a few tenths from
Rushville through Springfield to the Effingham/Flora areas. The
soundings further northeast toward Peoria and Bloomington generally
never really moisten the lower levels (except for the NAM), and will
keep those areas dry on Thursday.

Model trends for the Friday night/Saturday system continue to shift
more to the south, as the next deepening wave tracks into the lower
Mississippi Valley. Have limited the PoP`s for Friday night and
Saturday morning to areas south of I-70, where accumulations look to
be less than an inch. The ECMWF tries to draw some of the moisture
northward Saturday morning as a separate wave in the northern stream
swings into the Great Lakes region, so have kept some slight chances
during the morning across east central Illinois.

Active period setting up next week, as a broad long wave trough digs
southward through the central U.S. Some timing differences as to the
depth of this wave, with the ECMWF and parallel GFS cutting off a
low over southeast South Dakota and drifting it east, while the
operational GFS waits until mid week to cut off a broad low over the
Midwest. Both solutions yield precipitation as a storm system
organizes just to our northwest. Have continued to concentrate the
precip chances Monday night into Tuesday, mostly rain but perhaps
some snow mixed in across the far north. Will need to watch the
evolution of this closely, with the pre-holiday travel rush
beginning around this time.

&&

.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
ISSUED AT 528 AM CST WED DEC 17 2014

Widespread MVFR ceilings across central Illinois this morning,
with local IFR near KBMI will gradually erode from west to east
beginning this afternoon. Expect cloud cover to become SCT015-020
west of KDEC-KBMI, continuing BKN015 to the east through tonight.
Winds WNW 8-12 kts this morning decreasing through the afternoon
and evening.


&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...Barnes
SHORT TERM...Onton
LONG TERM...Geelhart
AVIATION...Onton






AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 533 AM CST WED DEC 17 2014

.SHORT TERM...
315 AM CST

THROUGH THURSDAY...

THE SYSTEM THAT BROUGHT A RETURN TO MORE SEASONAL TEMPERATURES IS
NOW CENTERED OVER THE EASTERN GREAT LAKES. THIS UPPER LOW IS
ROTATING AROUND A NOW DEEPER BUT SHEARING UPPER LOW CENTERED OVER
MINNESOTA AND WISCONSIN EARLY THIS MORNING. AT THE LOW-LEVELS THIS
SLOW MOVING PATTERN IS HELPING KEEP COLD AIR ADVECTION IN PLACE.
WHILE NOT PARTICULARLY STRONG FOR DECEMBER...THIS ADVECTION WITHIN
CYCLONIC FLOW HAS HELPED KEEP THE CLOUDS AND EVEN SOME FLURRIES.
EARLY MORNING SATELLITE IMAGERY INDICATES THE BACK EDGE CLEARING
FROM MINNEAPOLIS TO DES MOINES AND MAKING LITTLE PROGRESS. UPSTREAM
00Z SOUNDINGS AND CURRENT ACARS DATA FROM RFD INDICATE THE MOISTURE
DEPTH IS VERY SHALLOW. SO CERTAINLY THERE IS POTENTIAL TO SCATTER
FROM WEST TO EAST TODAY AND HIGH RESOLUTION GUIDANCE AND CONDENSATE
FIELDS DO PAINT THIS PICTURE AS WELL. GIVEN FURTHER STRENGTHENING OF
THE SUBSIDENCE INVERSION ON FORECAST SOUNDINGS ACROSS NORTH CENTRAL
ILLINOIS...HAVE GONE WITH FORECAST SCATTERING THERE BY EARLY
AFTERNOON. A LITTLE MORE TRICKY TOWARD CHICAGO AND NORTHWEST INDIANA
AND HAVE FAVORED THAT AREA REMAINING AT LEAST MOSTLY CLOUDY THROUGH
MUCH OF TODAY.

HIGH TEMPERATURES TODAY LOOK TO BE THEIR COOLEST IN ABOUT A WEEK
WITH UPPER 20S AND LOWER 30S SUPPORTED GIVEN LITTLE DIURNAL CLIMB
EXPECTED. THIS IS JUST A TAD BELOW MID-DECEMBER NORMALS. AS FOR
TONIGHT...LIKE A SONG ON REPEAT...THE CONFIDENCE ON CLOUDS ONCE
AGAIN IS LOW. WHILE SOME AREAS MAY SEE NOT MUCH FOR CLOUDS IN THE
EVENING...HIGH CLOUDS LOOK TO MOVE NORTHWARD OVER THE AREA LATE
TONIGHT. WITH LIGHTER WINDS THE POTENTIAL EXISTS FOR TEMPERATURES TO
DROP INTO THE LOWER TO MID TEENS IN OUTLYING AREAS.

THE GREAT LAKES BROAD UPPER LOW WILL MOVE EAST ON THURSDAY WEAKENING
THE CONFLUENT UPPER FLOW OVER THE FORECAST AREA. THIS WILL HELP A
SOUTHERN STREAM SYSTEM...CENTERED IN EASTERN ARIZONA EARLY THIS
MORNING...TO MAKE SOME INROADS WITH MID-LEVEL WARM AND MOIST
ADVECTION UP TO AT LEAST CENTRAL ILLINOIS AND INDIANA. THIS SHOULD
BRING CLOUDS TO MUCH OF THE AREA. HAVE NOT INCLUDED ANY LIGHT SNOW
IN THE FAR SOUTHERN AREA AT THIS TIME AS THE SUPPORT FOR LIFT STAYS
JUST SOUTH ON MOST GUIDANCE SOLUTIONS.

MTF

&&

.LONG TERM...
315 AM CST

FRIDAY THROUGH TUESDAY...

SURFACE HIGH PRESSURE RIDGING BASICALLY MAINTAINS ITSELF OVER THE
AREA THROUGH THE WEEKEND. THE UPPER PATTERN REMAINS SOMEWHAT SPLIT
WITH A SYSTEM LIKELY ENTIRELY PASSING TO OUR SOUTHEAST ON SATURDAY.
A NORTHERN STREAM UPPER LOW IS FORECAST TO BRING SOME PACIFIC
MOISTURE...MAINLY ALOFT...OVER THE AREA SATURDAY EVENING/OVERNIGHT.
LIFT IS WEAK AND MAINLY FOCUSED NORTH SO DO NOT HAVE ANY
POPS...HOWEVER HAVE INCREASED CLOUD COVER IN THE FORECAST AND WITH
THAT FORECAST MINS ON SATURDAY NIGHT.

THE WEATHER PATTERN ACROSS THE CENTRAL CONUS HAS BEEN CONSISTENTLY
FORECAST BY LONG RANGE MODELS AND ENSEMBLES TO BECOME MORE AMPLIFIED
DURING NEXT WEEK. JUST LOOKING ON HEMISPHERIC WATER VAPOR THIS
MORNING...MULTIPLE SYSTEMS ON ACTIVE JET ARE SEEN ACROSS THE
NORTHERN PACIFIC...SO A PATTERN SHIFT SEEMS LIKELY. THE CONSENSUS OF
GUIDANCE FAVORS AN ANOMALOUS SURFACE REFLECTION TO DEVELOP ACROSS
THE MIDWEST MONDAY INTO TUESDAY...THOUGH AS ONE CAN EXPECT THERE ARE
LARGE DIFFERENCES IN PLACEMENT.  HAVE INCREASED FORECAST POPS IN
LINE WITH A SMART GUIDANCE BLEND. GIVEN A CONSENSUS PLACEMENT
THOUGH...IT WOULD SEEM PROFILES WOULD BE MILD ENOUGH FOR MAINLY RAIN
AT FIRST IN OUR AREA. CERTAINLY THIS BECOMES A LOT MORE IN QUESTION
AS THE TROUGH FURTHER AMPLIFIES SUCH AS MODELS SUGGEST INTO
TUESDAY AND CHRISTMAS EVE.

MTF

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 12Z...

* MVFR CIGS THRU TONIGHT.
* GUSTY WEST/NORTHWEST WINDS THRU EARLY AFTERNOON. CMS

//DISCUSSION...UPDATED 12Z...

MAIN FORECAST CONCERN WILL BE WHEN MVFR CIGS WILL SCATTER OUT.
BACK EDGE STILL ACROSS CENTRAL IA AND EASTERN MN AND MAKING VERY
SLOW PROGRESS TO THE SOUTHEAST. FORECAST SOUNDINGS STILL SUGGEST
INVERSION ALOFT WILL BE STRONG ENOUGH TO TRAP THESE CLOUDS FOR
MOST OF THE DAYLIGHT HOURS AND POSSIBLY INTO THIS EVENING. SO
OPTED TO MAINTAIN MVFR CIGS INTO TONIGHT WITH SOME SCATTERING OR
CLEARING POSSIBLE OVERNIGHT...WHICH WILL LIKELY OCCUR FIRST AT RFD
AND POSSIBLY AS EARLY AS THIS EVENING.

A FEW FLURRIES WILL BE POSSIBLE THIS MORNING...BUT NO RESTRICTIONS
TO VIS EXPECTED.

WEST/NORTHWEST WINDS HAVE DIMINISHED SOME DURING THE EARLY MORNING
HOURS AND EXPECT THEM TO REMAIN GENERALLY STEADY INTO THIS
AFTERNOON...IN THE 10-15KT RANGE WITH GUSTS INTO THE MID/UPPER
TEENS. WINDS WILL SLOWLY DIMINISH THIS AFTERNOON THROUGH TONIGHT
AS THE GRADIENT SLOWLY WEAKENS. CMS

//ORD AND MDW CONFIDENCE...UPDATED 12Z...

* MEDIUM FOR CIGS THRU THE PERIOD.
* HIGH FOR WINDS THRU THE PERIOD. CMS

//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...

* THURSDAY NIGHT THROUGH SATURDAY...DRY/VFR. LIGHT/VRB WINDS.
* SUNDAY...DRY. MVFR POSSIBLE. SOUTH WINDS.
* MONDAY...CHANCE OF RAIN. MVFR LIKELY. GUSTY SOUTH WINDS.
* TUESDAY...CHANCE OF RAIN. IFR POSSIBLE. SOUTHWEST WINDS.

&&

.MARINE...

210 AM...LOW PRESSURE NEAR LAKE ONTARIO WILL MOVE EAST AND BE
ABSORBED BY LOW PRESSURE MOVING NORTH ALONG THE NEW ENGLAND COAST.
THIS LOW WILL THEN SLOWLY LIFT NORTHEAST AND DEEPEN OVER THE NEXT
FEW DAYS. A LARGE AREA OF HIGH PRESSURE EXTENDING FROM MANITOBA
INTO THE CENTRAL PLAINS WILL SLOWLY BUILD EAST ACROSS THE LAKES
REGION THURSDAY AND FRIDAY. NORTHWEST WINDS TO 30 KTS IN BETWEEN
THESE TWO SYSTEMS WILL GRADUALLY DIMINISH TONIGHT INTO THURSDAY.
AS THE HIGH DRIFTS ACROSS THE LAKES REGION...THERE WILL BE A
PERIOD OF LIGHT PERHAPS EVEN CALM WINDS FRIDAY NIGHT INTO SATURDAY
NIGHT UNTIL THE HIGH MOVES EAST SUNDAY AND SUNDAY NIGHT AND THE
FLOW TURNS BACK SOUTHERLY. CMS

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN
     UNTIL 10 AM WEDNESDAY.

     SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN
     UNTIL 10 AM THURSDAY.

&&

$$

VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO





Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
528 AM CST Wed Dec 17 2014

.SHORT TERM...(Today)
ISSUED AT 310 AM CST WED DEC 17 2014

A north-south oriented elongated high pressure ridge will edge
eastward toward Illinois today bringing with it a much lighter
surface pressure gradient and subsidence aloft. The result will be
wind speeds and gusts tapering off throughout the day as well as
thinning low cloud cover. Seasonably cold temperatures that arrived
after yesterday`s cold front will continue, with highs today only
around the freezing mark, just a few degrees below normal.
Although cloud cover will thin out through the day, current
indications are that the GFS and HRRR models are too aggressive in
clearing out low level moisture trapped below an inversion based
just below 900 mb. Forecast cloud cover is based more in line with
the NAM which keeps a saturated layer through the early part of
the day, slowly thinning through the afternoon. Meanwhile, periods
of high cloud cover will be arriving in the afternoon as well.

Also watching a band of snow flurries moving southward through Iowa
this morning. This looks as if it will remain west of the central IL
forecast area before the disturbance responsible for it ejects
eastward. This could move through portions of central IL later this
morning, but would be of very little consequence and is a fairly low
probability at this point.

&&

.LONG TERM...(Tonight through Tuesday)
ISSUED AT 310 AM CST WED DEC 17 2014

Upper wave currently pushing through Arizona on track to reach the
southern Plains tonight, before dampening out somewhat as it moves
across Missouri. Forecast soundings off most of the models are
showing the column moistening from the top down overnight, but very
dry air lingers just past sunrise below 800 mb. A short period of
isentropic lift on the 305K plane will move through central Illinois
Thursday morning, coinciding with the moistening of the lower
layers, resulting in a period of light snow across the southwestern
CWA during the morning. Current thinking is only a few tenths from
Rushville through Springfield to the Effingham/Flora areas. The
soundings further northeast toward Peoria and Bloomington generally
never really moisten the lower levels (except for the NAM), and will
keep those areas dry on Thursday.

Model trends for the Friday night/Saturday system continue to shift
more to the south, as the next deepening wave tracks into the lower
Mississippi Valley. Have limited the PoP`s for Friday night and
Saturday morning to areas south of I-70, where accumulations look to
be less than an inch. The ECMWF tries to draw some of the moisture
northward Saturday morning as a separate wave in the northern stream
swings into the Great Lakes region, so have kept some slight chances
during the morning across east central Illinois.

Active period setting up next week, as a broad long wave trough digs
southward through the central U.S. Some timing differences as to the
depth of this wave, with the ECMWF and parallel GFS cutting off a
low over southeast South Dakota and drifting it east, while the
operational GFS waits until mid week to cut off a broad low over the
Midwest. Both solutions yield precipitation as a storm system
organizes just to our northwest. Have continued to concentrate the
precip chances Monday night into Tuesday, mostly rain but perhaps
some snow mixed in across the far north. Will need to watch the
evolution of this closely, with the pre-holiday travel rush
beginning around this time.

&&

.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
ISSUED AT 528 AM CST WED DEC 17 2014

Widespread MVFR ceilings across central Illinois this morning,
with local IFR near KBMI will gradually erode from west to east
beginning this afternoon. Expect cloud cover to become SCT015-020
west of KDEC-KBMI, continuing BKN015 to the east through tonight.
Winds WNW 8-12 kts this morning decreasing through the afternoon
and evening.

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Onton
LONG TERM...Geelhart
AVIATION...Onton







AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 315 AM CST WED DEC 17 2014

.SHORT TERM...
315 AM CST

THROUGH THURSDAY...

THE SYSTEM THAT BROUGHT A RETURN TO MORE SEASONAL TEMPERATURES IS
NOW CENTERED OVER THE EASTERN GREAT LAKES. THIS UPPER LOW IS
ROTATING AROUND A NOW DEEPER BUT SHEARING UPPER LOW CENTERED OVER
MINNESOTA AND WISCONSIN EARLY THIS MORNING. AT THE LOW-LEVELS THIS
SLOW MOVING PATTERN IS HELPING KEEP COLD AIR ADVECTION IN PLACE.
WHILE NOT PARTICULARLY STRONG FOR DECEMBER...THIS ADVECTION WITHIN
CYCLONIC FLOW HAS HELPED KEEP THE CLOUDS AND EVEN SOME FLURRIES.
EARLY MORNING SATELLITE IMAGERY INDICATES THE BACK EDGE CLEARING
FROM MINNEAPOLIS TO DES MOINES AND MAKING LITTLE PROGRESS. UPSTREAM
00Z SOUNDINGS AND CURRENT ACARS DATA FROM RFD INDICATE THE MOISTURE
DEPTH IS VERY SHALLOW. SO CERTAINLY THERE IS POTENTIAL TO SCATTER
FROM WEST TO EAST TODAY AND HIGH RESOLUTION GUIDANCE AND CONDENSATE
FIELDS DO PAINT THIS PICTURE AS WELL. GIVEN FURTHER STRENGTHENING OF
THE SUBSIDENCE INVERSION ON FORECAST SOUNDINGS ACROSS NORTH CENTRAL
ILLINOIS...HAVE GONE WITH FORECAST SCATTERING THERE BY EARLY
AFTERNOON. A LITTLE MORE TRICKY TOWARD CHICAGO AND NORTHWEST INDIANA
AND HAVE FAVORED THAT AREA REMAINING AT LEAST MOSTLY CLOUDY THROUGH
MUCH OF TODAY.

HIGH TEMPERATURES TODAY LOOK TO BE THEIR COOLEST IN ABOUT A WEEK
WITH UPPER 20S AND LOWER 30S SUPPORTED GIVEN LITTLE DIURNAL CLIMB
EXPECTED. THIS IS JUST A TAD BELOW MID-DECEMBER NORMALS. AS FOR
TONIGHT...LIKE A SONG ON REPEAT...THE CONFIDENCE ON CLOUDS ONCE
AGAIN IS LOW. WHILE SOME AREAS MAY SEE NOT MUCH FOR CLOUDS IN THE
EVENING...HIGH CLOUDS LOOK TO MOVE NORTHWARD OVER THE AREA LATE
TONIGHT. WITH LIGHTER WINDS THE POTENTIAL EXISTS FOR TEMPERATURES TO
DROP INTO THE LOWER TO MID TEENS IN OUTLYING AREAS.

THE GREAT LAKES BROAD UPPER LOW WILL MOVE EAST ON THURSDAY WEAKENING
THE CONFLUENT UPPER FLOW OVER THE FORECAST AREA. THIS WILL HELP A
SOUTHERN STREAM SYSTEM...CENTERED IN EASTERN ARIZONA EARLY THIS
MORNING...TO MAKE SOME INROADS WITH MID-LEVEL WARM AND MOIST
ADVECTION UP TO AT LEAST CENTRAL ILLINOIS AND INDIANA. THIS SHOULD
BRING CLOUDS TO MUCH OF THE AREA. HAVE NOT INCLUDED ANY LIGHT SNOW
IN THE FAR SOUTHERN AREA AT THIS TIME AS THE SUPPORT FOR LIFT STAYS
JUST SOUTH ON MOST GUIDANCE SOLUTIONS.

MTF

&&

.LONG TERM...
315 AM CST

FRIDAY THROUGH TUESDAY...

SURFACE HIGH PRESSURE RIDGING BASICALLY MAINTAINS ITSELF OVER THE
AREA THROUGH THE WEEKEND. THE UPPER PATTERN REMAINS SOMEWHAT SPLIT
WITH A SYSTEM LIKELY ENTIRELY PASSING TO OUR SOUTHEAST ON SATURDAY.
A NORTHERN STREAM UPPER LOW IS FORECAST TO BRING SOME PACIFIC
MOISTURE...MAINLY ALOFT...OVER THE AREA SATURDAY EVENING/OVERNIGHT.
LIFT IS WEAK AND MAINLY FOCUSED NORTH SO DO NOT HAVE ANY
POPS...HOWEVER HAVE INCREASED CLOUD COVER IN THE FORECAST AND WITH
THAT FORECAST MINS ON SATURDAY NIGHT.

THE WEATHER PATTERN ACROSS THE CENTRAL CONUS HAS BEEN CONSISTENTLY
FORECAST BY LONG RANGE MODELS AND ENSEMBLES TO BECOME MORE AMPLIFIED
DURING NEXT WEEK. JUST LOOKING ON HEMISPHERIC WATER VAPOR THIS
MORNING...MULTIPLE SYSTEMS ON ACTIVE JET ARE SEEN ACROSS THE
NORTHERN PACIFIC...SO A PATTERN SHIFT SEEMS LIKELY. THE CONSENSUS OF
GUIDANCE FAVORS AN ANOMALOUS SURFACE REFLECTION TO DEVELOP ACROSS
THE MIDWEST MONDAY INTO TUESDAY...THOUGH AS ONE CAN EXPECT THERE ARE
LARGE DIFFERENCES IN PLACEMENT.  HAVE INCREASED FORECAST POPS IN
LINE WITH A SMART GUIDANCE BLEND. GIVEN A CONSENSUS PLACEMENT
THOUGH...IT WOULD SEEM PROFILES WOULD BE MILD ENOUGH FOR MAINLY RAIN
AT FIRST IN OUR AREA. CERTAINLY THIS BECOMES A LOT MORE IN QUESTION
AS THE TROUGH FURTHER AMPLIFIES SUCH AS MODELS SUGGEST INTO
TUESDAY AND CHRISTMAS EVE.

MTF

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 09Z...

* GUSTY WEST/NORTHWEST WINDS THRU THIS AFTERNOON.
* MVFR CIGS THRU THIS AFTERNOON. CMS

//DISCUSSION...UPDATED 09Z...

MVFR CIGS HAVE TRENDED A BIT LOWER...NOW IN THE 1500FT RANGE. NOT
EXPECTING IFR CIGS...BUT THEY COULD CONTINUE TO LOWER INTO THE
1000-1200FT RANGE OVER THE NEXT FEW HOURS. ALSO A FEW FLURRIES AT
TIMES...BUT NO RESTRICTION TO VIS EXPECTED. CMS

PREVIOUS 06Z DISCUSSION...

MVFR CIGS REMAIN LOCKED IN ACROSS MUCH OF THE REGION AND FORECAST
SOUNDINGS SUGGEST THESE MAY STAY TRAPPED UNDER AN INVERSION
THROUGH MUCH OF WEDNESDAY. CONFIDENCE IS FAIRLY LOW BUT OPTED TO
CONTINUE BKN CIGS UNTIL EVENING. NORTHWEST WINDS 12-16KTS WILL
SLOWLY DIMINISH WEDNESDAY MORNING INTO THE AFTERNOON. GUSTS ARE
STILL IN THE LOWER/MID 20KT RANGE AND THESE TOO WILL SLOWLY
DIMINISH THRU THE DAY...BUT LIKELY NOT COMPLETELY UNTIL LATE IN
THE AFTERNOON. CMS

//ORD AND MDW CONFIDENCE...UPDATED 09Z...

* MEDIUM FOR CIGS THRU THE PERIOD.
* HIGH FOR WINDS THRU THE PERIOD. CMS

//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...

* THURSDAY THROUGH MONDAY...DRY/VFR.

KJB

&&

.MARINE...

210 AM...LOW PRESSURE NEAR LAKE ONTARIO WILL MOVE EAST AND BE
ABSORBED BY LOW PRESSURE MOVING NORTH ALONG THE NEW ENGLAND COAST.
THIS LOW WILL THEN SLOWLY LIFT NORTHEAST AND DEEPEN OVER THE NEXT
FEW DAYS. A LARGE AREA OF HIGH PRESSURE EXTENDING FROM MANITOBA
INTO THE CENTRAL PLAINS WILL SLOWLY BUILD EAST ACROSS THE LAKES
REGION THURSDAY AND FRIDAY. NORTHWEST WINDS TO 30 KTS IN BETWEEN
THESE TWO SYSTEMS WILL GRADUALLY DIMINISH TONIGHT INTO THURSDAY.
AS THE HIGH DRIFTS ACROSS THE LAKES REGION...THERE WILL BE A
PERIOD OF LIGHT PERHAPS EVEN CALM WINDS FRIDAY NIGHT INTO SATURDAY
NIGHT UNTIL THE HIGH MOVES EAST SUNDAY AND SUNDAY NIGHT AND THE
FLOW TURNS BACK SOUTHERLY. CMS

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 10 AM
     WEDNESDAY.

     SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 10 AM THURSDAY.

&&

$$

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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
312 AM CST Wed Dec 17 2014

.SHORT TERM...(Today)
ISSUED AT 310 AM CST WED DEC 17 2014

A north-south oriented elongated high pressure ridge will edge
eastward toward Illinois today bringing with it a much lighter
surface pressure gradient and subsidence aloft. The result will be
wind speeds and gusts tapering off throughout the day as well as
thinning low cloud cover. Seasonably cold temperatures that arrived
after yesterday`s cold front will continue, with highs today only
around the freezing mark, just a few degrees below normal.
Although cloud cover will thin out through the day, current
indications are that the GFS and HRRR models are too aggressive in
clearing out low level moisture trapped below an inversion based
just below 900 mb. Forecast cloud cover is based more in line with
the NAM which keeps a saturated layer through the early part of
the day, slowly thinning through the afternoon. Meanwhile, periods
of high cloud cover will be arriving in the afternoon as well.

Also watching a band of snow flurries moving southward through Iowa
this morning. This looks as if it will remain west of the central IL
forecast area before the disturbance responsible for it ejects
eastward. This could move through portions of central IL later this
morning, but would be of very little consequence and is a fairly low
probability at this point.


&&

.LONG TERM...(Tonight through Tuesday)
ISSUED AT 310 AM CST WED DEC 17 2014

Upper wave currently pushing through Arizona on track to reach the
southern Plains tonight, before dampening out somewhat as it moves
across Missouri. Forecast soundings off most of the models are
showing the column moistening from the top down overnight, but very
dry air lingers just past sunrise below 800 mb. A short period of
isentropic lift on the 305K plane will move through central Illinois
Thursday morning, coinciding with the moistening of the lower
layers, resulting in a period of light snow across the southwestern
CWA during the morning. Current thinking is only a few tenths from
Rushville through Springfield to the Effingham/Flora areas. The
soundings further northeast toward Peoria and Bloomington generally
never really moisten the lower levels (except for the NAM), and will
keep those areas dry on Thursday.

Model trends for the Friday night/Saturday system continue to shift
more to the south, as the next deepening wave tracks into the lower
Mississippi Valley. Have limited the PoP`s for Friday night and
Saturday morning to areas south of I-70, where accumulations look to
be less than an inch. The ECMWF tries to draw some of the moisture
northward Saturday morning as a separate wave in the northern stream
swings into the Great Lakes region, so have kept some slight chances
during the morning across east central Illinois.

Active period setting up next week, as a broad long wave trough digs
southward through the central U.S. Some timing differences as to the
depth of this wave, with the ECMWF and parallel GFS cutting off a
low over southeast South Dakota and drifting it east, while the
operational GFS waits until mid week to cut off a broad low over the
Midwest. Both solutions yield precipitation as a storm system
organizes just to our northwest. Have continued to concentrate the
precip chances Monday night into Tuesday, mostly rain but perhaps
some snow mixed in across the far north. Will need to watch the
evolution of this closely, with the pre-holiday travel rush
beginning around this time.


&&

.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
ISSUED AT 1124 PM CST TUE DEC 16 2014

Cloudy skies will continue at all sites through most of the day.
Some clearing is being forecast by some of the models for PIA and
SPI during the afternoon, but rather be cautious and keep some
clouds around into the early evening hours. Even with drier and
cooler temps coming in for tomorrow, the inversion seems to hang
around til evening, trapping some of the moisture in. All clouds
will be MVFR levels, with BMI at IFR now and lasting until around
13z. So will have PIA and SPI scattering out first, but keeping a
4hr TEMPO group during the late morning and early evening hours
for broken MVFR cigs. For the other three sites, BMI, DEC, and
CMI, will maintain cloud cover at all sites into the evening
hours. DEC could scatter out sometime in the evening, but enough
uncertainty at the moment. BMI and CMI might begin to scatter out
around midnight. Northwest winds will continue next 24hrs with
wind speeds decreasing through the period as high pressure ridge
builds into the area. Wind gusts have diminish, but some sites
still maintaining some gusts. These gusts should drop off overnight.


&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Onton
LONG TERM...Geelhart
AVIATION...Auten






AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 1127 PM CST TUE DEC 16 2014

.SHORT TERM...
313 PM CST

TONIGHT THROUGH FRIDAY...

FILLING SURFACE LOW WAS OFF TO OUR EAST ACROSS THE CENTRAL GREAT
LAKES THIS AFTERNOON...BENEATH WEAKENING UPPER LEVEL LOW WHICH IS IN
THE PROCESS OF MERGING WITH STRONG DIGGING SHORT WAVE OVER THE UPPER
MISSISSIPPI VALLEY. THIS SECOND WAVE IS PROGGED TO SHEAR SOUTHEAST
ACROSS THE REGION TO THE EAST-SOUTHEAST AS IT REDEVELOPS INTO
REMNANT UPPER TROUGH TO THE EAST. VISIBLE SATELLITE IMAGERY SHOWS
MOST OF THE DEEPER CLOUD COVER HAS MOVED OFF TO THE EAST OF THE
FORECAST AREA...ALONG WITH THE BRUNT OF THE RADAR DETECTABLE
PRECIPITATION. EXPECT SOME PATCHY LIGHT RAIN/DRIZZLE AND PERHAPS A
FEW WET FLURRIES TO GRADUALLY END ACROSS THE AREA OVER THE NEXT FEW
HOURS AS MID-LEVELS CONTINUE TO DRY OUT...WITH 12Z RAOBS FROM
UPSTREAM LOCATIONS SUCH AS ABR AND OAX INDICATIVE OF MUCH DRIER AIR
ABOVE THE BOUNDARY LAYER. OTHERWISE...BLUSTERY WEST-NORTHWEST WINDS
WILL CONTINUE TO PULL COLDER AND DRIER AIR INTO THE AREA TONIGHT
WITH WINDS SLOW TO DIMINISH DUE TO LINGERING SURFACE TROUGHING
ACROSS THE UPPER MIDWEST. THOUGH REMAINING MOISTURE WILL BE SHALLOW
IT APPEARS CLOUD COVER WILL LINGER AT LEAST INTO EARLY WEDNESDAY
BEFORE STRONGER SUBSIDENCE CAN ERODE AND SCATTER CLOUDS MORE
EFFECTIVELY. DESPITE CLOUDS...UPSTREAM TEMPS ACROSS EASTERN IA ARE
ONLY IN THE LOW TO MID 20S AT THIS HOUR...SETTING THE STAGE FOR
CHILLIER TEMPS TONIGHT.

SHEARED MID-LEVEL VORTICITY AXIS FROM SHEARING UPPER MIDWEST SHORT
WAVE REMAINS OVER AREA WEDNESDAY..THOUGH HEIGHT RISES DO DEVELOP AS
THE NEW UPPER LOW DEEPENS OVER NEW ENGLAND. THIS ALLOWS THE GRADIENT
TO WEAKEN MORE QUICKLY ESPECIALLY DURING THE AFTERNOON AND
CONTINUING WEDNESDAY NIGHT AS SURFACE HIGH PRESSURE RIDGE MOVES
SLOWLY INTO WESTERN AND CENTRAL ILLINOIS. GUIDANCE DOES DEPICT A
SHORT WAVE APPROACHING FROM THE SOUTHERN PLAINS/LOWER MISSOURI
VALLEY AREA WEDNESDAY NIGHT...THOUGH THIS WAVE DAMPENS SIGNIFICANTLY
AS IT MOVES INTO THE UPPER RIDGE ACROSS THE MIDWEST. MODEL FORECAST
SOUNDINGS AND TIME-HEIGHT PLOTS INDICATE INCREASING MID-HIGH LEVEL
MOISTURE MAINLY AFTER MIDNIGHT WEDNESDAY NIGHT ACROSS OUR SOUTHWEST.
GUIDANCE (NAM...GFS...ECMWF AND SREF) DOES PRODUCE SOME LIGHT QPF
ACROSS CENTRAL ILLINOIS THURSDAY AS THIS WAVE CONTINUES TO
DEAMPLIFY...THOUGH FORECAST SOUNDINGS INDICATE LOW LEVELS INITIALLY
DRY AND SATURATION APPEARS INCOMPLETE MAKING PRECIP AT THE SURFACE A
LOW PROBABILITY. WEAKENING SURFACE HIGH PRESSURE RIDGE EVENTUALLY
MOVES INTO THE AREA THURSDAY NIGHT AND FRIDAY...ROUNDING OUT A FEW
DAYS OF MAINLY DRY AND SEASONABLY COOLER DAYS.

RATZER

&&

.LONG TERM...
313 PM CST

SATURDAY THROUGH TUESDAY...

ATTENTION TURNS TO A PAIR OF APPROACHING SHORT WAVE TROUGHS IN A
SOMEWHAT SPLIT FLOW REGIME. GUIDANCE HAS TRENDED WEAKER WITH THE
SOUTHERN STREAM DISTURBANCE...WHICH MOVES OUT ACROSS THE SOUTHERN
PLAINS AND GULF COAST STATES THROUGH SATURDAY. DECENT AGREEMENT IN
MODEL SOLUTIONS OF A MORE DIGGING NORTHERN STREAM WAVE COMING OUT OF
THE NORTHERN ROCKIES FRIDAY AND MOVING INTO THE LOWER MISSOURI AND
LOWER OHIO VALLEYS ON SATURDAY. WHILE MAIN SURFACE LOW PRESSURE
DEVELOPS WITH SOUTHERN SYSTEM ALONG THE GULF COAST...NORTHERN STREAM
FORCING DOES INDUCE AN INVERTED TROUGH INTO THE OHIO VALLEY SATURDAY
WHICH CONTINUES TO SUPPORT THE POTENTIAL FOR SOME LIGHT SNOW FROM
SOUTHERN/CENTRAL ILLINOIS INTO NORTHERN INDIANA...POSSIBLY INCLUDING
THE SOUTHEASTERN PART OF OUR CWA AS THE UPPER TROUGH MOVES OVERHEAD.
GUIDANCE STILL FOCUSES GREATER QPF SOUTHEAST OF THE FORECAST AREA...
BUT PRUDENT TO MAINTAIN SLIGHT CHANCES FOR SOME LIGHT ACCUMULATING
SNOW SOUTHEAST OF ABOUT A PONTIAC-VALPARAISO LINE. SURFACE HIGH
PRESSURE RIDGING QUICKLY BUILDS IN BEHIND THIS SYSTEM SATURDAY NIGHT
INTO SUNDAY. TEMPS DO MODERATE TO NORMAL FOR THE WEEKEND...GENERALLY
MID 20S AT NIGHT TO LOW/MID 30S BY DAY.

12Z GFS AND ECMWF RUNS HAVE COME INTO GOOD AGREEMENT IN BRINGING A
MORE AMPLIFIED UPPER TROUGH INTO THE CENTRAL CONUS SUNDAY NIGHT
THROUGH TUESDAY...WITH A STRONGER EMBEDDED SHORT WAVE MOVING ACROSS
THE UPPER MIDWEST LATE MONDAY-TUESDAY WITH DEEPENING LOW PRESSURE
PASSING TO OUR NORTH. THIS RESULTS IN WARMING TEMPERATURES ON
STRENGTHENING SOUTH WINDS...WITH THE POTENTIAL OF RAIN/SNOW CHANGING
TO RAIN BY LATE MONDAY AND CONTINUING TUESDAY AHEAD OF THE
APPROACHING COLD FRONT AS THE LOW MOVES ACROSS THE NORTHERN LAKES.
SOME DETAIL AND SPEED DIFFERENCES DO EXIST BETWEEN MODELS AND MUCH
COULD CHANGE BETWEEN NOW AND MONDAY...THOUGH IT DOES APPEAR THAT
COLDER AIR WOULD SPREAD INTO THE REGION LATER TUESDAY/TUESDAY NIGHT
WITH PRECIPITATION TAPERING OFF AS IT MIXES/CHANGES TO LIGHT SNOW.
COLDER AIR WOULD THEN ARRIVE IN TIME FOR THE CHRISTMAS HOLIDAY.

RATZER

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 06Z...

* GUSTY NORTHWEST WINDS THRU WEDNESDAY AFTERNOON.
* MVFR CIGS THRU WEDNESDAY AFTERNOON. CMS

//DISCUSSION...UPDATED 06Z...

MVFR CIGS REMAIN LOCKED IN ACROSS MUCH OF THE REGION AND FORECAST
SOUNDINGS SUGGEST THESE MAY STAY TRAPPED UNDER AN INVERSION
THROUGH MUCH OF WEDNESDAY. CONFIDENCE IS FAIRLY LOW BUT OPTED TO
CONTINUE BKN CIGS UNTIL EVENING. NORTHWEST WINDS 12-16KTS WILL
SLOWLY DIMINISH WEDNESDAY MORNING INTO THE AFTERNOON. GUSTS ARE
STILL IN THE LOWER/MID 20KT RANGE AND THESE TOO WILL SLOWLY
DIMINISH THRU THE DAY...BUT LIKELY NOT COMPLETELY UNTIL LATE IN
THE AFTERNOON. CMS

//ORD AND MDW CONFIDENCE...UPDATED 06Z...

* MEDIUM FOR CIGS THRU THE PERIOD.
* HIGH FOR WINDS THRU THE PERIOD. CMS

//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...

* THURSDAY THROUGH MONDAY...DRY/VFR.

KJB

&&

.MARINE...
130 PM CST

LOW PRESSURE AND A COLD FRONT HAVE PASSES EAST OF LAKE MICHIGAN AND
WINDS HAVE SHIFTED NORTHWESTERLY.  STRONG COLD ADVECTION AND STRONG
PRESSURE RISES AS THE LOW PULLS AWAY TO THE EAST AND HIGH PRESSURE
BUILDS ACROSS THE NORTHERN PLAINS WILL COMBINE TO DRIVE WINDS TO
30KT FOR THE REMAINDER OF THE AFTERNOON THROUGH TONIGHT AND MUCH OF
TOMORROW.  THERE IS THE POTENTIAL FOR A FEW GALE FORCE GUSTS...BUT
IN GENERAL...DO NOT EXPECT ENOUGH PREVAILING GALE FORCE WINDS TO
NECESSITATE A GALE WARNING.  HOWEVER...A SMALL CRAFT ADVISORY HAS
ALREADY BEEN ISSUED FOR THE NEARSHORE WATERS AND EXPECT THAT TO PLAY
OUT AS CURRENTLY ADVERTISED.  THE OVERALL PATTERN WILL BE SLOWLY
PROGRESSIVE...SO BRISK WINDS WILL REMAIN OVER THE LAKE THROUGH
THURSDAY...BUT AS HIGH PRESSURE BEGINS TO BUILD ACROSS THE WESTERN
GREAT LAKES...WINDS SHOULD DROP OFF AND BECOME MORE VARIABLE IN
DIRECTION.  HIGH PRESSURE WILL PREVAIL ACROSS THE GREAT LAKES FROM
LATE THURSDAY THROUGH THE WEEKEND...KEEPING WINDS RELATIVELY LIGHT
IN SPEED AND VARIABLE IN DIRECTION.  BY EARLY NEXT WEEK...THE HIGH
SHOULD FINALLY PUSH EAST OF LAKE MICHIGAN AS LOW PRESSURE BEGINS TO
DEVELOP OVER THE NORTHERN PLAINS.  THIS SHOULD SET UP A PERIOD OF
INCREASING SOUTHERLY WINDS FOR EARLY NEXT WEEK AS A LOW PRESSURE
SYSTEM DEEPENS WHILE CROSSING THE NORTHERN PLAINS AND DRAGGING A
TRAILING COLD FRONT ACROSS THE CENTRAL PLAINS.

KREIN

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN
     UNTIL 10 AM WEDNESDAY.

     SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN
     UNTIL 10 AM THURSDAY.

&&

$$

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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1124 PM CST Tue Dec 16 2014

.UPDATE...
ISSUED AT 901 PM CST TUE DEC 16 2014

Cloudy skies will continue overnight. Even with cooler and drier
air advecting into the area overnight, clouds should still keep
temps from dropping much overnight. Models still trying to bring
in some clearing during the early morning in western Illinois, but
with cyclonic flow, a deep layer of moisture, and an inversion,
believe clouds will hang around the area through late tomorrow.
Gradient will continue to loosen overnight, so gusts should
diminish later tonight, though wind speeds will still be 10-15kts
through early morning. so, current forecast looks good, so no
update needed at this time.

&&

.SHORT TERM...(Tonight)
ISSUED AT 230 PM CST TUE DEC 16 2014

Occluded low pressure system shifts into the eastern Great Lakes
this evening, allowing the gradient to gradually relax and decrease
wind gusts.  Latest NAM forecast soundings and HRRR ceiling guidance
suggest lower clouds will persist overnight, and given deep cyclonic
flow and in-building subsidence inversion at 900 MB, believe this
will hold true.  Therefore have increased cloud cover overnight.
Lows will be challenging with the full effect of CAA being offset by
insulating effects of cloud cover.  Have trended mins 2-3 degrees
warmer than MET/MAV blend, which gives lower 20s west of the IL
River, to mid 20s central/east.

&&

.LONG TERM...(Wednesday through Tuesday)
ISSUED AT 230 PM CST TUE DEC 16 2014

High pressure to settle into the region on Wednesday bringing in dry
with more seasonal temperatures. Forecast soundings...although not
as aggressive as yesterday with the low level moisture...continues
to indicate moisture trapped beneath a subsidence inversion will
keep a bit more cloudiness around the area during the day. Soundings
do show some breaks developing by late morning into the afternoon
hours but just in time to see mid and high level moisture/clouds
stream in ahead of our next weather system for Thursday. That weather
system is expected to spread light snow into parts of extreme west
central through southeast Illinois Thursday morning. Model runs had
been suggesting as the precip spread northeast into a more confluent
flow pattern over the lower Great Lakes coverage would decrease
during the day Thursday. Most of the operational models have backed
off that idea for now and have brought some light precip further north
and east into our area on Thursday so have brought precip chances further
north into the forecast area. Snowfall could accumulate up to 1 inch
from Springfield south Thursday morning before the area begins to
decrease in coverage during the afternoon.

Thursday`s system should be off to our east by evening with our attention
turning to a more significant wave over eastern Texas that will push
a surface low east-northeast across the Gulf Coast states Friday. The
northern periphery of the precip associated with the southern wave will
track over southeast Illinois with once again light snowfall for later
Friday night into Saturday. Current indications suggest an inch or less
for southeast Illinois. High pressure will then shift east into our
area for Sunday into early Monday bringing quiet weather to the region.

Quite a bit of model spread with respect to the system for early next
week, which will be moving southeast out of the Northern Plains and
tracking a strong low pressure system at the surface to our north
Monday. The operational GFS is more progressive with the early week
system and sweeps the cold front thru our area Tuesday afternoon and
evening with little if any southern stream interaction showing up
on the latest model run. In contrast, the latest ECMWF was indicating
a more phased look between the northern and southern streams which
effectively holds up the front pushing across our area later Tuesday
until a surface wave shifts off to our northeast Tuesday night.
This would bring rain on Tuesday, which would eventually change to
snow later in the day and evening as the deepening surface wave shifts
away from our area by Wednesday.

Seems as if each model run has a different solution with respect to
the pattern over the Midwest the first half of next week so not making
any significant changes to the grids at this point for days 7 and 8.
After our brief warm up ahead of the system on Monday and Tuesday, it
turns colder again by midweek.

&&

.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
ISSUED AT 1124 PM CST TUE DEC 16 2014

Cloudy skies will continue at all sites through most of the day.
Some clearing is being forecast by some of the models for PIA and
SPI during the afternoon, but rather be cautious and keep some
clouds around into the early evening hours. Even with drier and
cooler temps coming in for tomorrow, the inversion seems to hang
around til evening, trapping some of the moisture in. All clouds
will be MVFR levels, with BMI at IFR now and lasting until around
13z. So will have PIA and SPI scattering out first, but keeping a
4hr TEMPO group during the late morning and early evening hours
for broken MVFR cigs. For the other three sites, BMI, DEC, and
CMI, will maintain cloud cover at all sites into the evening
hours. DEC could scatter out sometime in the evening, but enough
uncertainty at the moment. BMI and CMI might begin to scatter out
around midnight. Northwest winds will continue next 24hrs with
wind speeds decreasing through the period as high pressure ridge
builds into the area. Wind gusts have diminish, but some sites
still maintaining some gusts. These gusts should drop off overnight.

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...Auten
SHORT TERM...25
LONG TERM...Smith
AVIATION...Auten






AREA FORECAST DISCUSSION

NWS DES MOINES IA

 529 PM CST THU DEC 18 2014

.SHORT TERM /TONIGHT/...
ISSUED AT 324 PM CST THU DEC 18 2014

SNOW HAS ENDED OVER THE SOUTHEASTERN CWA AS THE CULPRIT UPPER LEVEL
WAVE HAS RAPIDLY WEAKENED AND DGZ FORCING HAS WANED. BASED ON WEBCAM
IMAGES AND A FEW SPOTTER/COOP REPORTS...MOST AREAS IN THE SOUTHERN
THREE TIERS OF COUNTIES SAW LESS THAN AN INCH OF SNOW. ATTENTION NOW
TURNS UPSTREAM TO A LARGE STRATUS PLUME STRETCHING FROM NORTHWEST
MONTANA TO THE TEXAS PANHANDLE...WITH THE EASTERN FRONT NOW JUST
ABOUT TO ENTER THE WESTERN CWA. LIGHT WEST TO SOUTHWEST FLOW IN THE
LOWEST 1 KM OF THE ATMOSPHERE BEHIND A DEPARTING SURFACE RIDGE
SHOULD ADVECT THIS CLOUD MASS OVER CENTRAL IOWA TONIGHT AND KEEP
SKIES OVERCAST ALL NIGHT AND INTO TOMORROW MORNING. THE CLOUDS
SHOULD ALSO BOLSTER LOW TEMPS TONIGHT COMPARED TO PREVIOUS NIGHTS
AND DIDN`T DEVIATE MUCH FROM GUIDANCE IN THIS RESPECT.

THE BIGGEST UNCERTAINTY FOR TONIGHT IS THE POSSIBILITY OF FLURRIES
OR FREEZING DRIZZLE WEST OF I-35. SHORT-RANGE MODEL SOUNDINGS (RUC
AND HRRR IN PARTICULAR) SATURATE THE LOWEST 5 KFT OF THE ATMOSPHERE
IN THIS REGION TONIGHT WITH NEARLY ISOTHERMAL PROFILES IN THIS LAYER
HOVERING BETWEEN -4 AND -7C. WITH THIS CONDITIONAL ICE PROBABILITY
...WENT WITH A MIX OF OCCASIONAL FLURRIES AND PATCHY FZDZ. FORCING
SHOULD BE MARGINAL AT BEST AND NO ACCUMULATION OF SNOW OR ICE IS
ANTICIPATED. ANY LIFT WITH AN UPPER LEVEL TROUGH ON WATER VAPOR
IMAGERY NW OF THE CWA SHOULD STAY NORTH AND EAST OF THE AREA.
ISENTROPIC UPGLIDE IN THE LOWEST 100MB OF THE ATMOSPHERE IS
PRESENT...BUT AGAIN VERY WEAK.

.LONG TERM /FRIDAY THROUGH THURSDAY/...
ISSUED AT 324 PM CST THU DEC 18 2014

THE WEATHER IN THE LONG TERM WILL IN GENERAL BE MORE ACTIVE THEN
WHAT WE HAVE SEEN IN A WHILE.  FRIDAY THROUGH SUNDAY THERE WILL BE
NUMEROUS RELATIVELY WEAK SHORT WAVES MOVE ACROSS IOWA IN A GENERALLY
ZONAL FLOW.  THROUGH SATURDAY MOISTURE WILL EITHER BE SPARSE OR
SHALLOW SO I AM NOT EXPECTING MUCH WITH THESE SHORTWAVES IN TERMS OF
SENSIBLE WEATHER EXCEPT FOR CLOUD COVER.  TEMPS SHOULD BE RATHER
MILD FOR MID TO LATE DECEMBER.

SATURDAY NIGHT THROUGH SUNDAY A LITTLE STRONGER SHORT WAVE MOVES IN
AND MOISTURE DEPTH INCREASES SLIGHTLY ALTHOUGH IT IS STILL VERY
SHALLOW.  SOUNDINGS DO NOT INDICATE ICE INTRODUCTION AND WHILE THERE
ARE MODEL DIFFERENCES AS TO WHERE ANY WEAK FORCING MIGHT OCCUR...IT
DOES APPEAR THAT THE NORTHERN HALF OF IOWA IS MORE LIKELY TO SEE
THIS THAN SOUTHERN IOWA.  AS A RESULT I KEPT THE MENTION OF FREEZING
DRIZZLE CONFINED TO THE NORTH.  THE SOUNDING DOES SATURATE
OR BEGIN TO SATURATE SUFFICIENTLY LATE SATURDAY NIGHT THROUGH
SUNDAY MORNING THROUGH THE DENDRITIC ZONE THAT WE COULD TRANSITION
TO SOME LIGHT SNOW UP NORTH...ESPECIALLY SUNDAY MORNING. THAT
SHORTWAVE EXITS DURING THE EARLY AFTERNOON AND TEMPS WARM
SUFFICIENTLY FOR A WINTERY MIX CHANGING TO RAIN ACROSS AT LEAST
SOME OF THE AREA.

SUNDAY NIGHT THROUGH MONDAY A MORE POTENT SHORTWAVE MOVES INTO
IOWA...AFFECTING THE WEST SUNDAY NIGHT AND THE REST OF THE AREA
THROUGH TUESDAY.  HERE MODELS DIVERGE ON HOW TO HANDLE THIS SYSTEM.
THE GFS KEEP THE UPPER LEVEL WAVE OPEN AND DEVELOPS A CLOSED SURFACE
LOW OVER CENTRAL TO NORTHEAST IOWA.  THE EURO DRASTICALLY DEPEND
THE UPPER WAVE TO OUR WEST THEN CONTINUES TO DEVELOP IT INTO A
CLOSED LOW MONDAY NIGHT AND TUESDAY ACROSS EASTERN IOWA.  THE
RESULTANT CLOSED SURFACE LOW IS OVER EASTERN IOWA AS WELL AND
FURTHER SOUTHWEST THAN THE GFS HAS.  THE GFS REALLY DEVELOPS THE QG
FORCING ACROSS CENTRAL IOWA SUNDAY NIGHT THEN IS SIGNIFICANTLY
WEAKER THROUGH TUESDAY.  SOUNDINGS SHOW A PROFILE THAT IS PRETTY
WARM THROUGH MONDAY AFTERNOON WHEN THE PROFILE COOLS TO BELOW
FREEZING.  PRECIP THROUGH EARLY MONDAY AFTERNOON SHOULD BE RAIN WITH
AN OCCASIONAL WINTERY MIX ESPECIALLY UP NORTH.  DURING THE AFTERNOON
WE WILL BE TRANSITIONING TO A RAIN/SNOW MIX BEFORE GOING TO ALL SNOW
MONDAY NIGHT.  IT IS TOO FAR OUT TO CONSIDER SNOWFALL AMOUNTS YET
AND GIVEN THE MODEL DISCREPANCIES IT WOULD BE HARD TO DO AT THIS
POINT.

THAT SYSTEM PULLS OUT BY CHRISTMAS EVE LEAVING US WITH SEASONAL
TEMPS AND MAINLY DRY.  ANOTHER SYSTEM PUSHES IN FOR THURSDAY NIGHT
AND FRIDAY AND GIVEN THE STRENGTH OF THE TROUGH OVER US THAT FAR OUT
WE WILL GET SOME PRECIP OUT OF THE SYSTEM BUT MODEL DISCREPANCIES
ARE TOO BIG TO GIVE MUCH IN THE WAY OF TIMING AND AMOUNT DETAILS.

&&

.AVIATION...19/00Z
ISSUED AT 529 PM CST THU DEC 18 2014

WIDESPREAD CLOUDINESS IS EXPECTED FOR THE DURATION OF THE FORECAST
WITH LOW MVFR TO IFR STRATUS BECOMING COMMON PLACE LATE TONIGHT
INTO FRIDAY. IN EFFECT...WILL SEE LOW LEVEL WARM ADVECTION VERY
GRADUALLY INCREASE WITH WEAK MOISTURE TRANSPORT ACROSS IOWA
HELPING TO KEEP STATUS PERSISTENT. SURFACE WIND FLOW WILL BE WEAK
AND GRADUALLY BECOME SOUTHEAST TO SOUTH ON FRIDAY. VISIBILITIES
MAY ALSO SEE SOME RESTRICTIONS IN LIGHT FOG LATE TONIGHT.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...SKOW
LONG TERM...FAB
AVIATION...COGIL




AREA FORECAST DISCUSSION

NWS DES MOINES IA

 306 PM CST WED DEC 17 2014

.SHORT TERM /TONIGHT/...
ISSUED AT 245 PM CST WED DEC 17 2014

A QUIET AFTERNOON IS IN STORE FOR THE CWA WITH SURFACE HIGH PRESSURE
ANCHORED ALONG THE MISSOURI RIVER VALLEY. A SHARP 300 MB SHORTWAVE
TROUGH CURRENTLY EJECTING FROM THE FOUR CORNERS REGION WILL ENTER
SOUTHWEST IOWA BY 12Z THURSDAY. NAM/GFS ARE TOO SLOW WITH RETURNING
MID-LEVEL MOISTURE (MANIFESTING ITSELF AS AN ALTOSTRATUS DECK) NOW
WELL INTO SW IOWA AS WELL AS WITH PRECIP COVERAGE WITH THIS SYSTEM
IN OKLAHOMA. THE HRRR BEST REFLECTS REALITY IN TERMS OF PRECIP
COVERAGE BUT IS ABOUT 3 HOURS BEHIND THE CURVE WITH CLOUD PLACEMENT.
HAVE SUBSEQUENTLY MANUALLY INCREASED CLOUD COVER OVER THE SW HALF OF
THE CWA AND USED THE HRRR FOR TIMING THE ONSET OF SNOW IN THE
SOUTHWESTERN CWA. LOW TEMPERATURES TONIGHT...ESPECIALLY OVER THE
NORTH...WILL BE DEPENDENT ON HOW QUICKLY CLOUDS CAN ADVECT OVERHEAD.
THESE WILL NEED TO BE MONITORED THIS EVENING AND ADJUSTED UPWARD
SHOULD THE CLOUDS ADVANCE FASTER THAN CURRENTLY FORECAST.

THE FASTER MOISTURE RETURN THROWS JUST ANOTHER WRENCH IN TIMING AND
AMOUNTS OF SNOWFALL IN SOUTHERN IOWA LATE TONIGHT. 12/18Z MODEL BUFR
SOUNDINGS DEPICT A STOUT 925-850MB DRY WEDGE ATTENDANT WITH THE
SURFACE RIDGE...BUT THIS MIDLEVEL MOISTURE MAY SATURATE THE COLUMN
FASTER THAN PROGGED AND LEAD TO HIGHER SNOWFALL TOTALS. OVERALL MADE
LITTLE CHANGES TO THE FORECAST IN THIS RESPECT...BUT DID TIGHTEN THE
POP GRADIENT AS IT ADVANCES NORTHEAST FROM 09 TO 12Z THINKING THAT
THE LOW LEVEL DRY AIR WILL RESULT IN A SHARP CUTOFF IN ACCUMULATING
SNOW.

.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
ISSUED AT 245 PM CST WED DEC 17 2014

A FEW CHALLENGES OVER THE EXTENDED PERIOD...WITH A NUMBER OF WEAK
SYSTEMS TO AFFECT PORTIONS OF THE AREA THROUGH THE PERIOD. SPLIT
FLOW CONTINUES TO BE THE MAIN DRIVING FORCE BEHIND THE RATHER
QUIESCENT WEATHER FOR MID DECEMBER. RATHER HIGH AMPLITUDE RIDGE OF
HIGH PRESSURE STILL ANCHORED FROM THE NORTHERN PLAINS TO THE GULF
COAST NEXT FEW DAYS. FIRST WAVE CURRENTLY OVER THE SOUTHERN
PLAINS TODAY AND SHOULD MOVE NORTHEAST THROUGH THU MORNING. AHEAD
OF THE WEAK SYSTEM WARM AIR ADVECTION AND LIMITED MOISTURE WILL BE
FORCED UPWARD IN AN AREA OF ISENTROPIC LIFT OVER SOUTHERN IOWA
THURSDAY. THE LIFT AND MOISTURE WILL BE ATTEMPTING TO OVERCOME THE
DRY AIRMASS CURRENTLY IN PLACE...LIMITING OVERALL AMOUNTS. THIS
WILL RESULT IN SOME RATHER LIGHT SNOW DURING THE MORNING HOURS
WITH MINOR ACCUMULATIONS GENERALLY LESS THAN AN INCH. DURING THE
EARLY AFTERNOON HOURS...BUFR SOUNDINGS SHOW THAT WE LOSE ICE
INTRODUCTION ACROSS THE SOUTHWEST AND SOUTH. HAVE INTRODUCED SOME
PATCHY FREEZING DRIZZLE ALONG WITH VERY LIGHT SNOW DURING THE
AFTERNOON HOURS...THOUGH EXPECTATIONS ARE THAT ANY PRECIPITATION
BY THAT TIME WILL BE VERY LIGHT AND LITTLE IF ANY ICE ACCUMULATION
IS EXPECTED. NEXT SYSTEM ARRIVES BY SUNDAY AND MONDAY AND EXTENDS
INTO TUESDAY. LOWER CONFIDENCE MOVING FORWARD WITH A CONSENSUS
SOLUTION AS THE GFS IS QUITE MILD WHILE THE EURO IS NOW SUGGESTING
A SOLUTION WITH MORE SIGNIFICANT DYNAMIC COOLING AS THE PRECIP
ARRIVES INTO MONDAY. THE EURO SUGGESTS MORE SNOW THAN RAIN/SNOW
MIX. GIVEN THE EVENT IS STILL 5 DAYS AWAY...WILL HOLD ONTO CURRENT
MIX TRENDS FOR NOW...AND MONITOR DURING SUBSEQUENT MODEL PACKAGES.
THE ONE TREND THAT IS BEGINNING TO EMERGE IS COLDER AIR AS NEXT
WEEK PROGRESSES. AS A STRONG PACNW STREAM WAVE ADVANCES EAST INTO
THE WESTERN STATES...MIDWEST RIDGE FINALLY BEGINS TO BREAK DOWN
AND BECOME DISPLACED BY A LONG WAVE TROUGH. THIS SHOULD SPELL A
TRANSITION TO A MORE ACTIVE AND COLDER PATTERN TOWARD THE END OF
THE EXTENDED. AS THE WAVE TUESDAY DEEPENS...A RATHER STRONG SFC
WAVE WILL EJECT NORTH NORTHEAST OUT OF EASTERN TEXAS TO EASTERN
MICHIGAN WEDNESDAY. GIVEN THE CURRENT GFS/EURO PACKAGES...THE MAIN
H850 MOISTURE PLUME...BETTER FORCING...AND HIGHER PRECIPITATION
AMOUNTS WILL PROBABLY END UP EAST OF THE REGION. WILL MONITOR FOR
GENERAL WESTWARD DRIFT NEXT SEVERAL PACKAGES...THIS SOMETIMES
OCCURS WITH WINTER STORM EVOLUTION IN MODEL PACKAGES...FIRST
PROJECTING THE EVENT TOO FAR EAST THEN PULLING IT BACK AS THE
EVENT NEARS.

&&

.AVIATION...17/18Z
ISSUED AT 1145 AM CST WED DEC 17 2014

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT...THOUGH PATCHES OF
MVFR STRATUS ARE POSSIBLE AROUND MCW AND ALO THIS AFTERNOON BUT
CONFIDENCE WAS NOT HIGH ENOUGH TO MENTION IN THE TAFS. LOWER CIGS
AND SNOW MOVE INTO SOUTHERN IOWA AFTER 06Z...THOUGH HOW FAR NORTH
THE SNOW PROGRESSES WILL BE A CHALLENGE FOR THE DSM/FOD TAFS.
BEST CHANCE OF MVFR CIGS/VSBYS WILL BE AT OTM FROM 12Z TO THE END
OF THE TAF PERIOD.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...SKOW
LONG TERM...REV
AVIATION...SKOW



AREA FORECAST DISCUSSION

NWS DES MOINES IA

 1141 AM CST WED DEC 17 2014

.UPDATE...
ISSUED AT 1145 AM CST WED DEC 17 2014

MINOR SKY ADJUSTMENTS WERE MADE FOR THE AFTERNOON FORECAST TO
REFLECT THE CLEARER CONDITIONS IN NORTHERN IOWA. STRATOCUMULUS
DECK IS TRYING TO REFORM OVER THE FAR NE CWA BUT HAS BEEN
STRUGGLING TO ADVANCE MUCH INTO BREMER AND BLACK HAWK COUNTIES.

&&

.SHORT TERM /TODAY/...
ISSUED AT 344 AM CST WED DEC 17 2014

NO SIGNIFICANT WEATHER OF CONCERN TODAY...BUT TEMPS MAY BE A TAD
PROBLEMATIC. RIGHT ENTRANCE REGION OF IA/IL JET SEGMENT AND WEAK
FORCING DRIVEN BY WRN KS SHORT WAVE AHEAD OF SWRN CONUS TROUGH
CONTINUE TO SPREAD TOKEN MID CLOUDS AND PRECIP ALOFT INTO SWRN
IA. FORCING REMAINS OF SIMILAR MAGNITUDE THROUGHOUT THE DAY...IS
MAINLY 3KM AND ABOVE...AND CONTINUES TO ADVANCE INTO SURFACE RIDGE
SO NO PRECIP IS ANTICIPATED THROUGH VALID PERIOD.

MODELS ARE HAVING SOME DIFFICULTY HANDLING CURRENT TEMP REGIME.
TEMPS HAVE COOLED BELOW SOME MODELS WHERE SKIES HAVE CLEARED. HIGH
RES MODELS ARE DOING BETTER THAN TRADITIONAL OPERATIONAL RUNS AS
HRRR...RAP AND GEM REGIONAL MODELS BETTER RESEMBLE REALITY.
QUESTION IS WHETHER TO EXTRAPOLATE THEIR SOLUTIONS INTO THE FUTURE
AS THEY VARY QUITE A BIT. RAP AND GEM REGIONAL KEEP THINGS QUITE
COOL WITH MINIMAL REBOUND WHILE HRRR IS BACK UP TOWARD MODEL
CONSENSUS BY AFTERNOON. EVEN THOUGH WINDS WILL DIMINISH SOMEWHAT
IN THE SURFACE RIDGE...STILL EXPECT SOME MIXING WITHOUT SNOW COVER
SO HAVE ONLY GONE JUST A TOUCH BELOW MODEL CONSENSUS WHICH IS NOT
DISSIMILAR TO MOS SUGGESTIONS.

.LONG TERM /TONIGHT THROUGH MONDAY/...
ISSUED AT 344 AM CST WED DEC 17 2014

A WEAK 500 MB TROUGH WILL PROGRESS ACROSS KANSAS AND MISSOURI ON
WEDNESDAY NIGHT AND THURSDAY...SPREADING LIGHT PRECIPITATION THAT
MAY MAKE IT INTO MAINLY SOUTHERN IOWA. HOWEVER...THERE WILL BE A
SURFACE HIGH PRESSURE RIDGE BUILD ACROSS THE STATE DURING THAT
TIME RESULTING IN LOW LEVEL DRY AIR ISSUES AS DEPICTED BY MOST
FORECAST SOUNDINGS. IT APPEARS PROBABLE THAT THERE WILL AT LEAST
BE SOME FLURRIES OR VERY LIGHT SNOW ACROSS OUR SOUTHERN
COUNTIES...BUT FURTHER NORTH PRECIPITATION IS MUCH LESS LIKELY AND
EVEN IN THE SOUTH ANY ACCUMULATIONS SHOULD BE LIGHT. HAVE
MAINTAINED CHANCE POPS LATE WEDNESDAY NIGHT AND THURSDAY MORNING
WITH SNOWFALL AMOUNTS AROUND AN INCH OR LESS AND GENERALLY LIMITED
TO I-80 SOUTHWARD. THERE IS A POSSIBILITY OF FREEZING DRIZZLE AT
TIMES IF THE CLOUD LAYER IS SUFFICIENTLY SHALLOW/WARM...HOWEVER AT
THIS TIME THAT IS AN UNLIKELY SCENARIO AND IT HAS NOT BEEN
INCLUDED IN THE FORECAST DUE TO THE LOW PROBABILITY OF
OCCURRENCE.

FROM THURSDAY NIGHT THROUGH SATURDAY THE AFOREMENTIONED SURFACE
HIGH PRESSURE RIDGE WILL REMAIN ANCHORED JUST TO OUR EAST...FROM
THE GREAT LAKES DOWN ACROSS ILLINOIS...RESULTING IN VERY LIGHT
SOUTHERLY FLOW AND LIKELY SEVERAL MORE DAYS OF LOW STRATUS CLOUDS
THAT WILL LIMIT TEMPERATURE FLUCTUATIONS. HAVE INCREASED CLOUD
COVER FORECAST AND COMPRESSED DIURNAL TEMPERATURE SPREADS
ACCORDINGLY. IT IS PROBABLE THAT THIS WILL MANIFEST AS MORE
DRY BUT CLOUDY AND DREARY WEATHER TO END THE WORK WEEK.

BY SATURDAY A LONGWAVE 500 MB TROUGH WILL BE CROSSING THE ROCKIES
AND SHAPING UP TO BE A BIG PLAYER IN OUR WEATHER FOR THE FIRST
HALF OF NEXT WEEK. THE TROUGH WILL REACH THE HIGH PLAINS AND THE
MIDWEST BY SUNDAY AND SUBSEQUENTLY DEEPEN AS IT IS REINFORCED BY A
SERIES OF SUCCESSIVE SHORTWAVE IMPULSES ENTERING THE TROUGH FROM
WESTERN CANADA. BY TUESDAY BOTH THE ECMWF AND GFS ARE NOW CARVING
OUT A MASSIVE 500 MB TROUGH ACROSS MOST OF THE CONUS...WITH A
CENTRAL CLOSED LOW SOMEWHERE OVER THE UPPER MIDWEST. FOR OUR
FORECAST AREA THIS SCENARIO WILL TRANSLATE INTO A PROLONGED PERIOD
OF PRECIPITATION CHANCES...BEGINNING SOMETIME AROUND SUNDAY OR
SUNDAY NIGHT AND PERSISTING AT INTERVALS AT LEAST THROUGH TUESDAY.
HOWEVER...PRECIPITATION TYPE WILL BE HEAVILY DEPENDENT ON THE
LOCATION OF THE UPPER AND SURFACE LOW PRESSURE CENTERS AND THEIR
ASSOCIATED THERMAL PROFILES. CURRENT LONG RANGE MODEL SOLUTIONS
SUPPORT A FAIRLY LONG PERIOD OF RAIN WITH SNOW MORE LIMITED TO
NORTHERN IOWA AND LATER IN THE EVENT...LIKELY RESULTING IN LOW
SNOWFALL AMOUNTS. HOWEVER...WITH THE SYSTEM STILL FOUR OR FIVE
DAYS AWAY AND NOT EVEN ENTERING THE RAOB NETWORK UNTIL AROUND
FRIDAY...THE SOLUTIONS ARE HARDLY STABLE AND A WIDE RANGE OF
EVENTUAL OUTCOMES IS POSSIBLE SO THE FORECAST WILL LIKELY BE
FLUCTUATING IN THE COMING DAYS. ALL INTERESTS WITH TRAVEL PLANS
AROUND CHRISTMAS SHOULD CONTINUE TO MONITOR THESE TRENDS AND HOPE
THAT TEMPERATURES STAY WARM ENOUGH FOR THE PRECIPITATION TO FALL
PREDOMINANTLY AS RAIN.

&&

.AVIATION...17/18Z
ISSUED AT 1145 AM CST WED DEC 17 2014

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT...THOUGH PATCHES OF
MVFR STRATUS ARE POSSIBLE AROUND MCW AND ALO THIS AFTERNOON BUT
CONFIDENCE WAS NOT HIGH ENOUGH TO MENTION IN THE TAFS. LOWER CIGS
AND SNOW MOVE INTO SOUTHERN IOWA AFTER 06Z...THOUGH HOW FAR NORTH
THE SNOW PROGRESSES WILL BE A CHALLENGE FOR THE DSM/FOD TAFS.
BEST CHANCE OF MVFR CIGS/VSBYS WILL BE AT OTM FROM 12Z TO THE END
OF THE TAF PERIOD.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...SKOW
SHORT TERM...SMALL
LONG TERM...LEE
AVIATION...SKOW




AREA FORECAST DISCUSSION

NWS QUAD CITIES IA IL

 1139 AM CST WED DEC 17 2014

.UPDATE...
ISSUED AT 1133 AM CST WED DEC 17 2014

CLOUDS HAVE BROKEN UP OVER ROUGHLY THE WESTERN HALF OF THE AREA
BUT COLD AIR ALOFT HAS ALLOWED DIURNAL CLOUDS TO DEVELOP. THE
CLEARING WILL SLOWLY MOVE EAST THROUGH THE AFTERNOON BUT THE
EASTERN THIRD OF THE AREA MAY ONLY SEE A PEEK OF SUN PRIOR TO SUNSET.

&&

.SYNOPSIS...
ISSUED AT 348 AM CST WED DEC 17 2014

REGION REMAINS ENTRENCHED IN COLD CYCLONIC FLOW WITH STRATUS AND
A FEW FLURRIES ON BACKSIDE OF EASTERN CONUS LONGWAVE TROUGH
AND EMBEDDED SHEARING CLOSED CIRCULATION OVER THE UPPER MIDWEST.
TEMPS RUNNING ON AVERAGE 20-25 DEGS COLDER FROM 24 HRS AGO WITH
READINGS IN THE UPPER TEENS TO MID 20S... WITH NW WIND 10-15+ MPH
MAKING IT FEEL EVEN COLDER AND MORE LIKE THE SINGLE DIGITS TO
LOWER TEENS. WATER VAPOR IMAGERY SHOWS ACTIVE SOUTHERN BRANCH OF
JET STREAM WITH SEVERAL EMBEDDED PERTURBATIONS MOVING THROUGH THE
SOUTHWESTERN CONUS. PRIMARY DISTURBANCE OF INTEREST WAS LOCATED
NEAR BAJA CA AND EXPECTED TO LIFT OUT ACROSS THE SOUTHERN PLAINS
AND MID-MISSISSIPPI VLY TONIGHT AND THURSDAY... AND MAY BRUSH THE
SOUTHERN CWA WITH SOME LIGHT SNOW OR FLURRIES.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CST WED DEC 17 2014

MAIN CHALLENGES ARE CLOUD TRENDS WITH IMPACT ON TEMPS... AND THE
POTENTIAL FOR LIGHT SNOW ACROSS THE SOUTHERN CWA LATE TONIGHT.

FOG ENHANCEMENT SATL IMAGERY SHOWS THE BACK EDGE OF THE STRATUS
MAINLY ALONG AND EAST OF I-35 PROGRESSING SLOWLY E/SE WITH
MORE EXPANSIVE AREA OVER SOUTHEAST MN MOVING NEARLY DUE SOUTH
AHEAD OF SHEARING CLOSED CIRCULATION. THE LATEST RAP SOUNDINGS
SUGGEST STRATUS MAY REMAIN TRAPPED UNDER INVERSION FOR MOST OF
THE DAY... WHILE NAM WOULD MAINTAIN STRATUS THROUGH MID AM BEFORE
BREAKING UP FROM WEST TO EAST. MODELS IN GENERAL HAVE BEEN TOO
OPTIMISTIC WITH CLEARING TRENDS... BUT WITH FLOW BECOMING MORE
ANTICYCLONIC TO NEARLY NEUTRAL AHEAD OF PLAINS SFC RIDGE BUILDING
IN AND AS A MID LEVEL SUBSIDENCE REGION SOUTH OF SHEARING CLOSED
CIRCULATION OVERSPREADS THE AREA TODAY BELIEVE PROSPECTS GOOD
FOR AT LEAST PARTIAL CLEARING LATER TODAY AND INTO THIS EVENING.
WHERE STRATUS BREAKS UP EXPECT SOME HIGH THIN CIRRUS ESPECIALLY
SOUTH HALF AHEAD OF SOUTHWEST SYSTEM. AS CLOUDS GO... SO GO THE
TEMPS AND HAVE STAYED NEAR GUIDANCE BLEND OR ON THE COLD SIDE WITH
HIGHS FROM MID 20S TO LOWER 30S. IF STRATUS REMAINS TRAPPED
UNDER THE INVERSION ALL DAY PER RAP SOUNDINGS THEN TEMPS STRUGGLE
WITH WIDESPREAD MID TO SOME UPPER 20S. GRADIENT TO WEAKEN TODAY
ESPECIALLY THIS AFTERNOON SO WINDS BECOMING MUCH LESS OF A FACTOR
ON THE CHILLS.

TONIGHT... SHORTWAVE TROUGH PROGGED TO LIFT FROM SOUTHERN PLAINS
TOWARD THE MID-MISSISSIPPI VLY BY 12Z ALTHOUGH IT LOOKS TO
DAMPEN/WEAKEN MARKEDLY AS IT MOVES INTO UPPER RIDGING OVER THE
MIDWEST. MODEL TIME-HEIGHT PLOTS AND SOUNDINGS DEPICT INCREASING
MID-HIGH LEVEL MOISTURE OVERNIGHT MAINLY SOUTHWESTERN 1/3-1/2 OF
THE CWA. GEM...GFS AND ECMWF ALL GENERATE SOME VERY LIGHT QPF
ACROSS THE FAR SOUTHWEST CWA LATE TONIGHT... BUT CLOSER INSPECTION
OF SOUNDINGS SHOW LOW LEVELS REMAIN DRY AND SATURATION INCOMPLETE
FOR MORE THAN JUST FLURRIES. GIVEN THAT THIS WILL BE VERY LATE
(AFT 09Z) DEVELOPING AND LOW CONFIDENCE WITH SATURATION COMPOUNDED
BY WEAKENING SYSTEM HAVE OPTED TO KEEP FCST DRY FAR SOUTH AND OMIT
ANY MENTION OF FLURRIES FOR NOW. LOWS QUITE CHALLENGING DUE TO
CLOUD COVER TRENDS. HAVE KEPT LOWS WITH GUIDANCE BLEND OR ON THE
COOL SIDE AND IN THE TEENS TO AROUND 20 DEGS. 850 MB TEMPS OF
AROUND -5C COUPLED WITH NEAR CALM WINDS AND ANY CLEARING WOULD
SUPPORT COLDEST MINS OF MID TEENS 13-16F.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 348 AM CST WED DEC 17 2014

FORECAST FOCUS ON A CHANCE OF LIGHT SNOW IN OUR FAR SOUTH THURSDAY
THEN ANOTHER CHANCE OF PRECIPITATION EARLY NEXT WEEK.

THURSDAY...OPERATIONAL MODELS DISAGREE ON MOISTURE/SATURATION AS A
SHORT WAVE TRACKS FROM THE SOUTHERN ROCKIES INTO THE MID MS VALLEY
IN THE MORNING. THE ECMWF/GEM ARE THE MOST AGGRESSIVE WITH LIGHT QPF
IN OUR SOUTHERN CWA WHILE THE AMERICAN MODELS ARE ESSENTIALLY DRY.
FORECAST SOUNDINGS INDICATE DRY LOW LEVELS SO IT WILL REMAIN TO BE
SEEN HOW MUCH THE LOW LEVELS CAN SATURATE. FOR COLLABORATION REASONS
I HAVE BUMPED UP POPS TO 40 IN EXTREME NORTHEAST MO...WITH SLIGHTS
AS FAR NORTH AS A FAIRFIELD TO MACOMB LINE. FARTHER NORTH IN THE CWA
THE DRY AIR IS FIRMLY ENTRENCHED WITH HIGH PRESSURE CENTERED IN THE
UPPER MIDWEST. ANY ACCUMULATIONS WILL BE MINOR AND WE ARE TALKING
ONLY A COUPLE OF TENTHS OF AN INCH IN EXTREME NORTHEAST MO. THE WAVE
MOVES QUICKLY INTO THE OHIO VALLEY DURING THE AFTERNOON WITH
LINGERING FLURRIES POSSIBLE. I HAVE LOWERED POPS IN THE AFTERNOON IN
OUR FAR SOUTH TO LESS THAN 20. MAXIMUM TEMPERATURES WILL RANGE FROM
THE UPPER 20S NORTH TO THE LOWER 30S SOUTH.

FRIDAY THROUGH SUNDAY...STORM SYSTEM IN THE SOUTHERN STREAM IS STILL
INDICATED BY MODELS TO REMAIN WELL SOUTH OF THE CWA. AN UPPER LEVEL
TROUGH MOVES ACROSS THE MIDWEST BUT AIRMASS IS TOO DRY TO MENTION
ANY MEASURABLE PRECIPITATION...AS THE DEEPER MOISTURE IS TIED TO THE
SOUTHERN STREAM STORM. HIGH TEMPERATURES DURING THIS PERIOD WILL BE
MAINLY IN THE 30S WITH LOWS IN THE 20S.

MONDAY AND TUESDAY...NEXT IN YOUR HIT PARADE IS A DEEPENING TROUGH
THAT DIGS INTO THE MIDWEST. OPERATIONAL MODELS ARE FAIRLY SIMILAR
WITH THIS FEATURE. HIGH END CHANCE POPS ARE IN THE GRIDS FOR THIS
SITUATION BUT PLENTY OF ROOM TO GO HIGHER OVER THE NEXT SEVERAL DAYS.
WITH THE SURFACE LOW REMAINING TO OUR NORTH THIS SETS UP THE
POTENTIAL FOR RAIN OR A RAIN/SNOW MIX BUT THEN TURNING TO ALL SNOW
BY THE TIME WE GET TO TUESDAY AFTERNOON AND TUESDAY NIGHT.

REMAINDER OF CHRISTMAS WEEK...MODELS HAVING DIFFICULTY WITH PHASING
ISSUES AS THE 00Z/17 ECMWF CRANKS UP A WHOPPER OF A WINTER STORM
(BOMBOGENESIS) TRACKING FROM THE LOWER MS VALLEY TO THE GREAT LAKES
CHRISTMAS EVE...WITH ARCTIC AIR PLUNGING QUICKLY INTO THE COUNTRY
BEHIND THE SYSTEM. THE GFS IS FARTHER EAST AND DEEPENS THE STORM IN
NEW ENGLAND INSTEAD. BEING A WEEK AWAY THERE LIKELY WILL BE MORE
CHANGES BUT CHRISTMAS TRAVELERS WILL WANT TO STAY TUNED.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1133 AM CST WED DEC 17 2014

MVFR CIGS WILL SLOWLY CLEAR ACROSS EASTERN IOWA AND NORTHERN
ILLINOIS THROUGH 00Z/18 AS HIGH PRESSURE BUILDS INTO THE MIDWEST.
AFT 00Z/18 VFR CONDITIONS ARE EXPECTED THROUGH 12Z/18. AFT 12Z/18
SNOW WILL SLOWLY MOVE INTO SOUTHEAST IOWA PRODUCING MVFR AND
POSSIBLY IFR CONDITIONS.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&

$$

UPDATE...08
SYNOPSIS...05
SHORT TERM...05
LONG TERM...HAASE
AVIATION...08






AREA FORECAST DISCUSSION

NWS DES MOINES IA

 603 AM CST WED DEC 17 2014

.SHORT TERM /TODAY/...
ISSUED AT 344 AM CST WED DEC 17 2014

NO SIGNIFICANT WEATHER OF CONCERN TODAY...BUT TEMPS MAY BE A TAD
PROBLEMATIC. RIGHT ENTRANCE REGION OF IA/IL JET SEGMENT AND WEAK
FORCING DRIVEN BY WRN KS SHORT WAVE AHEAD OF SWRN CONUS TROUGH
CONTINUE TO SPREAD TOKEN MID CLOUDS AND PRECIP ALOFT INTO SWRN
IA. FORCING REMAINS OF SIMILAR MAGNITUDE THROUGHOUT THE DAY...IS
MAINLY 3KM AND ABOVE...AND CONTINUES TO ADVANCE INTO SURFACE RIDGE
SO NO PRECIP IS ANTICIPATED THROUGH VALID PERIOD.

MODELS ARE HAVING SOME DIFFICULTY HANDLING CURRENT TEMP REGIME.
TEMPS HAVE COOLED BELOW SOME MODELS WHERE SKIES HAVE CLEARED. HIGH
RES MODELS ARE DOING BETTER THAN TRADITIONAL OPERATIONAL RUNS AS
HRRR...RAP AND GEM REGIONAL MODELS BETTER RESEMBLE REALITY.
QUESTION IS WHETHER TO EXTRAPOLATE THEIR SOLUTIONS INTO THE FUTURE
AS THEY VARY QUITE A BIT. RAP AND GEM REGIONAL KEEP THINGS QUITE
COOL WITH MINIMAL REBOUND WHILE HRRR IS BACK UP TOWARD MODEL
CONSENSUS BY AFTERNOON. EVEN THOUGH WINDS WILL DIMINISH SOMEWHAT
IN THE SURFACE RIDGE...STILL EXPECT SOME MIXING WITHOUT SNOW COVER
SO HAVE ONLY GONE JUST A TOUCH BELOW MODEL CONSENSUS WHICH IS NOT
DISSIMILAR TO MOS SUGGESTIONS.

.LONG TERM /TONIGHT THROUGH MONDAY/...
ISSUED AT 344 AM CST WED DEC 17 2014

A WEAK 500 MB TROUGH WILL PROGRESS ACROSS KANSAS AND MISSOURI ON
WEDNESDAY NIGHT AND THURSDAY...SPREADING LIGHT PRECIPITATION THAT
MAY MAKE IT INTO MAINLY SOUTHERN IOWA. HOWEVER...THERE WILL BE A
SURFACE HIGH PRESSURE RIDGE BUILD ACROSS THE STATE DURING THAT
TIME RESULTING IN LOW LEVEL DRY AIR ISSUES AS DEPICTED BY MOST
FORECAST SOUNDINGS. IT APPEARS PROBABLE THAT THERE WILL AT LEAST
BE SOME FLURRIES OR VERY LIGHT SNOW ACROSS OUR SOUTHERN
COUNTIES...BUT FURTHER NORTH PRECIPITATION IS MUCH LESS LIKELY AND
EVEN IN THE SOUTH ANY ACCUMULATIONS SHOULD BE LIGHT. HAVE
MAINTAINED CHANCE POPS LATE WEDNESDAY NIGHT AND THURSDAY MORNING
WITH SNOWFALL AMOUNTS AROUND AN INCH OR LESS AND GENERALLY LIMITED
TO I-80 SOUTHWARD. THERE IS A POSSIBILITY OF FREEZING DRIZZLE AT
TIMES IF THE CLOUD LAYER IS SUFFICIENTLY SHALLOW/WARM...HOWEVER AT
THIS TIME THAT IS AN UNLIKELY SCENARIO AND IT HAS NOT BEEN
INCLUDED IN THE FORECAST DUE TO THE LOW PROBABILITY OF
OCCURRENCE.

FROM THURSDAY NIGHT THROUGH SATURDAY THE AFOREMENTIONED SURFACE
HIGH PRESSURE RIDGE WILL REMAIN ANCHORED JUST TO OUR EAST...FROM
THE GREAT LAKES DOWN ACROSS ILLINOIS...RESULTING IN VERY LIGHT
SOUTHERLY FLOW AND LIKELY SEVERAL MORE DAYS OF LOW STRATUS CLOUDS
THAT WILL LIMIT TEMPERATURE FLUCTUATIONS. HAVE INCREASED CLOUD
COVER FORECAST AND COMPRESSED DIURNAL TEMPERATURE SPREADS
ACCORDINGLY. IT IS PROBABLE THAT THIS WILL MANIFEST AS MORE
DRY BUT CLOUDY AND DREARY WEATHER TO END THE WORK WEEK.

BY SATURDAY A LONGWAVE 500 MB TROUGH WILL BE CROSSING THE ROCKIES
AND SHAPING UP TO BE A BIG PLAYER IN OUR WEATHER FOR THE FIRST
HALF OF NEXT WEEK. THE TROUGH WILL REACH THE HIGH PLAINS AND THE
MIDWEST BY SUNDAY AND SUBSEQUENTLY DEEPEN AS IT IS REINFORCED BY A
SERIES OF SUCCESSIVE SHORTWAVE IMPULSES ENTERING THE TROUGH FROM
WESTERN CANADA. BY TUESDAY BOTH THE ECMWF AND GFS ARE NOW CARVING
OUT A MASSIVE 500 MB TROUGH ACROSS MOST OF THE CONUS...WITH A
CENTRAL CLOSED LOW SOMEWHERE OVER THE UPPER MIDWEST. FOR OUR
FORECAST AREA THIS SCENARIO WILL TRANSLATE INTO A PROLONGED PERIOD
OF PRECIPITATION CHANCES...BEGINNING SOMETIME AROUND SUNDAY OR
SUNDAY NIGHT AND PERSISTING AT INTERVALS AT LEAST THROUGH TUESDAY.
HOWEVER...PRECIPITATION TYPE WILL BE HEAVILY DEPENDENT ON THE
LOCATION OF THE UPPER AND SURFACE LOW PRESSURE CENTERS AND THEIR
ASSOCIATED THERMAL PROFILES. CURRENT LONG RANGE MODEL SOLUTIONS
SUPPORT A FAIRLY LONG PERIOD OF RAIN WITH SNOW MORE LIMITED TO
NORTHERN IOWA AND LATER IN THE EVENT...LIKELY RESULTING IN LOW
SNOWFALL AMOUNTS. HOWEVER...WITH THE SYSTEM STILL FOUR OR FIVE
DAYS AWAY AND NOT EVEN ENTERING THE RAOB NETWORK UNTIL AROUND
FRIDAY...THE SOLUTIONS ARE HARDLY STABLE AND A WIDE RANGE OF
EVENTUAL OUTCOMES IS POSSIBLE SO THE FORECAST WILL LIKELY BE
FLUCTUATING IN THE COMING DAYS. ALL INTERESTS WITH TRAVEL PLANS
AROUND CHRISTMAS SHOULD CONTINUE TO MONITOR THESE TRENDS AND HOPE
THAT TEMPERATURES STAY WARM ENOUGH FOR THE PRECIPITATION TO FALL
PREDOMINANTLY AS RAIN.

&&

.AVIATION...17/12Z
ISSUED AT 600 AM CST WED DEC 17 2014

PRIMARY CONCERN WILL BE DEPARTING STRATUS THIS MORNING. BACK EDGE
OF SUB 2KFT MVFR CIGS EXTENDS FROM KLWD-KTNU-KALO AND SHOULD EXIT
KALO MOMENTARILY AND ARE NOT INCLUDED IN THAT TAF. CIGS SHOULD
LINGER AT KOTM FOR A FEW MORE HOURS. AFTER THAT VFR CONDITIONS ARE
ANTICIPATED WITH NOTHING MORE THAN SCT-BKN MID AND HIGH CLOUDINESS
GRADUALLY INCREASING FROM THE WEST. WINDS WILL REMAIN FAIRLY
LIGHT...SLOWLY VEERING INTO THE NIGHT AND BECOMING LIGHT AND
VARIABLE EARLY THU MORNING.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...SMALL
LONG TERM...LEE
AVIATION...SMALL



AREA FORECAST DISCUSSION

NWS QUAD CITIES IA IL

 352 AM CST WED DEC 17 2014

.SYNOPSIS...
ISSUED AT 348 AM CST WED DEC 17 2014

REGION REMAINS ENTRENCHED IN COLD CYCLONIC FLOW WITH STRATUS AND
A FEW FLURRIES ON BACKSIDE OF EASTERN CONUS LONGWAVE TROUGH
AND EMBEDDED SHEARING CLOSED CIRCULATION OVER THE UPPER MIDWEST.
TEMPS RUNNING ON AVERAGE 20-25 DEGS COLDER FROM 24 HRS AGO WITH
READINGS IN THE UPPER TEENS TO MID 20S... WITH NW WIND 10-15+ MPH
MAKING IT FEEL EVEN COLDER AND MORE LIKE THE SINGLE DIGITS TO
LOWER TEENS. WATER VAPOR IMAGERY SHOWS ACTIVE SOUTHERN BRANCH OF
JET STREAM WITH SEVERAL EMBEDDED PERTURBATIONS MOVING THROUGH THE
SOUTHWESTERN CONUS. PRIMARY DISTURBANCE OF INTEREST WAS LOCATED
NEAR BAJA CA AND EXPECTED TO LIFT OUT ACROSS THE SOUTHERN PLAINS
AND MID-MISSISSIPPI VLY TONIGHT AND THURSDAY... AND MAY BRUSH THE
SOUTHERN CWA WITH SOME LIGHT SNOW OR FLURRIES.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CST WED DEC 17 2014

MAIN CHALLENGES ARE CLOUD TRENDS WITH IMPACT ON TEMPS... AND THE
POTENTIAL FOR LIGHT SNOW ACROSS THE SOUTHERN CWA LATE TONIGHT.

FOG ENHANCEMENT SATL IMAGERY SHOWS THE BACK EDGE OF THE STRATUS
MAINLY ALONG AND EAST OF I-35 PROGRESSING SLOWLY E/SE WITH
MORE EXPANSIVE AREA OVER SOUTHEAST MN MOVING NEARLY DUE SOUTH
AHEAD OF SHEARING CLOSED CIRCULATION. THE LATEST RAP SOUNDINGS
SUGGEST STRATUS MAY REMAIN TRAPPED UNDER INVERSION FOR MOST OF
THE DAY... WHILE NAM WOULD MAINTAIN STRATUS THROUGH MID AM BEFORE
BREAKING UP FROM WEST TO EAST. MODELS IN GENERAL HAVE BEEN TOO
OPTIMISTIC WITH CLEARING TRENDS... BUT WITH FLOW BECOMING MORE
ANTICYCLONIC TO NEARLY NEUTRAL AHEAD OF PLAINS SFC RIDGE BUILDING
IN AND AS MID LEVEL SUBSIDENT REGION SOUTH OF SHEARING CLOSED
CIRCULATION OVERSPREADS THE AREA TODAY BELIEVE PROSPECTS GOOD
FOR AT LEAST PARTIAL CLEARING LATER TODAY AND INTO THIS EVENING.
WHERE STRATUS BREAKS UP EXPECT SOME HIGH THIN CIRRUS ESPECIALLY
SOUTH HALF AHEAD OF SOUTHWEST SYSTEM. AS CLOUDS GO... SO GO THE
TEMPS AND HAVE STAYED NEAR GUIDANCE BLEND OR ON THE COLD SIDE WITH
HIGHS FROM MID 20S TO LOWER 30S. IF STRATUS REMAINS TRAPPED
UNDER THE INVERSION ALL DAY PER RAP SOUNDINGS THEN TEMPS STRUGGLE
WITH WIDESPREAD MID TO SOME UPPER 20S. GRADIENT TO WEAKEN TODAY
ESPECIALLY THIS AFTERNOON SO WINDS BECOMING MUCH LESS OF A FACTOR
ON THE CHILLS.

TONIGHT... SHORTWAVE TROUGH PROGGED TO LIFT FROM SOUTHERN PLAINS
TOWARD THE MID-MISSISSIPPI VLY BY 12Z ALTHOUGH IT LOOKS TO
DAMPEN/WEAKEN MARKEDLY AS IT MOVES INTO UPPER RIDGING OVER THE
MIDWEST. MODEL TIME-HEIGHT PLOTS AND SOUNDINGS DEPICT INCREASING
MID-HIGH LEVEL MOISTURE OVERNIGHT MAINLY SOUTHWESTERN 1/3-1/2 OF
THE CWA. GEM...GFS AND ECMWF ALL GENERATE SOME VERY LIGHT QPF
ACROSS THE FAR SOUTHWEST CWA LATE TONIGHT... BUT CLOSER INSPECTION
OF SOUNDINGS SHOW LOW LEVELS REMAIN DRY AND SATURATION INCOMPLETE
FOR MORE THAN JUST FLURRIES. GIVEN THAT THIS WILL BE VERY LATE
(AFT 09Z) DEVELOPING AND LOW CONFIDENCE WITH SATURATION COMPOUNDED
BY WEAKENING SYSTEM HAVE OPTED TO KEEP FCST DRY FAR SOUTH AND OMIT
ANY MENTION OF FLURRIES FOR NOW. LOWS QUITE CHALLENGING DUE TO
CLOUD COVER TRENDS. HAVE KEPT LOWS WITH GUIDANCE BLEND OR ON THE
COOL SIDE AND IN THE TEENS TO AROUND 20 DEGS. 850 MB TEMPS OF
AROUND -5C COUPLED WITH NEAR CALM WINDS AND ANY CLEARING WOULD
SUPPORT COLDEST MINS OF MID TEENS 13-16F.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 348 AM CST WED DEC 17 2014

FORECAST FOCUS ON A CHANCE OF LIGHT SNOW IN OUR FAR SOUTH THURSDAY
THEN ANOTHER CHANCE OF PRECIPITATION EARLY NEXT WEEK.

THURSDAY...OPERATIONAL MODELS DISAGREE ON MOISTURE/SATURATION AS A
SHORT WAVE TRACKS FROM THE SOUTHERN ROCKIES INTO THE MID MS VALLEY
IN THE MORNING. THE ECMWF/GEM ARE THE MOST AGGRESSIVE WITH LIGHT QPF
IN OUR SOUTHERN CWA WHILE THE AMERICAN MODELS ARE ESSENTIALLY DRY.
FORECAST SOUNDINGS INDICATE DRY LOW LEVELS SO IT WILL REMAIN TO BE
SEEN HOW MUCH THE LOW LEVELS CAN SATURATE. FOR COLLABORATION REASONS
I HAVE BUMPED UP POPS TO 40 IN EXTREME NORTHEAST MO...WITH SLIGHTS
AS FAR NORTH AS A FAIRFIELD TO MACOMB LINE. FARTHER NORTH IN THE CWA
THE DRY AIR IS FIRMLY ENTRENCHED WITH HIGH PRESSURE CENTERED IN THE
UPPER MIDWEST. ANY ACCUMULATIONS WILL BE MINOR AND WE ARE TALKING
ONLY A COUPLE OF TENTHS OF AN INCH IN EXTREME NORTHEAST MO. THE WAVE
MOVES QUICKLY INTO THE OHIO VALLEY DURING THE AFTERNOON WITH
LINGERING FLURRIES POSSIBLE. I HAVE LOWERED POPS IN THE AFTERNOON IN
OUR FAR SOUTH TO LESS THAN 20. MAXIMUM TEMPERATURES WILL RANGE FROM
THE UPPER 20S NORTH TO THE LOWER 30S SOUTH.

FRIDAY THROUGH SUNDAY...STORM SYSTEM IN THE SOUTHERN STREAM IS STILL
INDICATED BY MODELS TO REMAIN WELL SOUTH OF THE CWA. AN UPPER LEVEL
TROUGH MOVES ACROSS THE MIDWEST BUT AIRMASS IS TOO DRY TO MENTION
ANY MEASURABLE PRECIPITATION...AS THE DEEPER MOISTURE IS TIED TO THE
SOUTHERN STREAM STORM. HIGH TEMPERATURES DURING THIS PERIOD WILL BE
MAINLY IN THE 30S WITH LOWS IN THE 20S.

MONDAY AND TUESDAY...NEXT IN YOUR HIT PARADE IS A DEEPENING TROUGH
THAT DIGS INTO THE MIDWEST. OPERATIONAL MODELS ARE FAIRLY SIMILAR
WITH THIS FEATURE. HIGH END CHANCE POPS ARE IN THE GRIDS FOR THIS
SITUATION BUT PLENTY OF ROOM TO GO HIGHER OVER THE NEXT SEVERAL DAYS.
WITH THE SURFACE LOW REMAINING TO OUR NORTH THIS SETS UP THE
POTENTIAL FOR RAIN OR A RAIN/SNOW MIX BUT THEN TURNING TO ALL SNOW
BY THE TIME WE GET TO TUESDAY AFTERNOON AND TUESDAY NIGHT.

REMAINDER OF CHRISTMAS WEEK...MODELS HAVING DIFFICULTY WITH PHASING
ISSUES AS THE 00Z/17 ECMWF CRANKS UP A WHOPPER OF A WINTER STORM
(BOMBOGENESIS) TRACKING FROM THE LOWER MS VALLEY TO THE GREAT LAKES
CHRISTMAS EVE...WITH ARCTIC AIR PLUNGING QUICKLY INTO THE COUNTRY
BEHIND THE SYSTEM. THE GFS IS FARTHER EAST AND DEEPENS THE STORM IN
NEW ENGLAND INSTEAD. BEING A WEEK AWAY THERE LIKELY WILL BE MORE
CHANGES BUT CHRISTMAS TRAVELERS WILL WANT TO STAY TUNED.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1131 PM CST TUE DEC 16 2014

LINGERING LOW CLOUDS OVER IL AND THE EASTERN HALF OF IA WILL BE
SLOW TO MOVE OUT LATE TONIGHT AND WEDNESDAY MORNING...RESULTING IN
CONTINUED MVFR CONDITIONS DUE TO CIGS. SCATTERED FLURRIES WILL
REMAIN POSSIBLE ESPECIALLY AT CID AND MLI LATE TONIGHT. THE
UPDATED FORECASTS CONTINUE A GRADUAL CLEARING TREND...LIFTING
CLOUD BASES TO WELL ABOVE MVFR THRESHOLDS...IN A LOW CONFIDENCE
12Z TO 18Z TIMEFRAME. THERE IS HIGHER CONFIDENCE THAT ALL SITES
WILL BE VFR FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY EVENING. NW
WINDS WILL DIMINISH THROUGHOUT AND BECOMING LIGHT FROM THE NORTH
WEDNESDAY NIGHT AS HIGH PRESSURE BUILDS INTO THE UPPER MS VALLEY.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&

$$

SYNOPSIS...05
SHORT TERM...05
LONG TERM...HAASE
AVIATION...SHEETS





AREA FORECAST DISCUSSION

NWS DES MOINES IA

 344 AM CST WED DEC 17 2014

.SHORT TERM /TODAY/...
ISSUED AT 344 AM CST WED DEC 17 2014

NO SIGNIFICANT WEATHER OF CONCERN TODAY...BUT TEMPS MAY BE A TAD
PROBLEMATIC. RIGHT ENTRANCE REGION OF IA/IL JET SEGMENT AND WEAK
FORCING DRIVEN BY WRN KS SHORT WAVE AHEAD OF SWRN CONUS TROUGH
CONTINUE TO SPREAD TOKEN MID CLOUDS AND PRECIP ALOFT INTO SWRN
IA. FORCING REMAINS OF SIMILAR MAGNITUDE THROUGHOUT THE DAY...IS
MAINLY 3KM AND ABOVE...AND CONTINUES TO ADVANCE INTO SURFACE RIDGE
SO NO PRECIP IS ANTICIPATED THROUGH VALID PERIOD.

MODELS ARE HAVING SOME DIFFICULTY HANDLING CURRENT TEMP REGIME.
TEMPS HAVE COOLED BELOW SOME MODELS WHERE SKIES HAVE CLEARED. HIGH
RES MODELS ARE DOING BETTER THAN TRADITIONAL OPERATIONAL RUNS AS
HRRR...RAP AND GEM REGIONAL MODELS BETTER RESEMBLE REALITY.
QUESTION IS WHETHER TO EXTRAPOLATE THEIR SOLUTIONS INTO THE FUTURE
AS THEY VARY QUITE A BIT. RAP AND GEM REGIONAL KEEP THINGS QUITE
COOL WITH MINIMAL REBOUND WHILE HRRR IS BACK UP TOWARD MODEL
CONSENSUS BY AFTERNOON. EVEN THOUGH WINDS WILL DIMINISH SOMEWHAT
IN THE SURFACE RIDGE...STILL EXPECT SOME MIXING WITHOUT SNOW COVER
SO HAVE ONLY GONE JUST A TOUCH BELOW MODEL CONSENSUS WHICH IS NOT
DISSIMILAR TO MOS SUGGESTIONS.

.LONG TERM /TONIGHT THROUGH MONDAY/...
ISSUED AT 344 AM CST WED DEC 17 2014

A WEAK 500 MB TROUGH WILL PROGRESS ACROSS KANSAS AND MISSOURI ON
WEDNESDAY NIGHT AND THURSDAY...SPREADING LIGHT PRECIPITATION THAT
MAY MAKE IT INTO MAINLY SOUTHERN IOWA. HOWEVER...THERE WILL BE A
SURFACE HIGH PRESSURE RIDGE BUILD ACROSS THE STATE DURING THAT
TIME RESULTING IN LOW LEVEL DRY AIR ISSUES AS DEPICTED BY MOST
FORECAST SOUNDINGS. IT APPEARS PROBABLE THAT THERE WILL AT LEAST
BE SOME FLURRIES OR VERY LIGHT SNOW ACROSS OUR SOUTHERN
COUNTIES...BUT FURTHER NORTH PRECIPITATION IS MUCH LESS LIKELY AND
EVEN IN THE SOUTH ANY ACCUMULATIONS SHOULD BE LIGHT. HAVE
MAINTAINED CHANCE POPS LATE WEDNESDAY NIGHT AND THURSDAY MORNING
WITH SNOWFALL AMOUNTS AROUND AN INCH OR LESS AND GENERALLY LIMITED
TO I-80 SOUTHWARD. THERE IS A POSSIBILITY OF FREEZING DRIZZLE AT
TIMES IF THE CLOUD LAYER IS SUFFICIENTLY SHALLOW/WARM...HOWEVER AT
THIS TIME THAT IS AN UNLIKELY SCENARIO AND IT HAS NOT BEEN
INCLUDED IN THE FORECAST DUE TO THE LOW PROBABILITY OF
OCCURRENCE.

FROM THURSDAY NIGHT THROUGH SATURDAY THE AFOREMENTIONED SURFACE
HIGH PRESSURE RIDGE WILL REMAIN ANCHORED JUST TO OUR EAST...FROM
THE GREAT LAKES DOWN ACROSS ILLINOIS...RESULTING IN VERY LIGHT
SOUTHERLY FLOW AND LIKELY SEVERAL MORE DAYS OF LOW STRATUS CLOUDS
THAT WILL LIMIT TEMPERATURE FLUCTUATIONS. HAVE INCREASED CLOUD
COVER FORECAST AND COMPRESSED DIURNAL TEMPERATURE SPREADS
ACCORDINGLY. IT IS PROBABLE THAT THIS WILL MANIFEST AS MORE
DRY BUT CLOUDY AND DREARY WEATHER TO END THE WORK WEEK.

BY SATURDAY A LONGWAVE 500 MB TROUGH WILL BE CROSSING THE ROCKIES
AND SHAPING UP TO BE A BIG PLAYER IN OUR WEATHER FOR THE FIRST
HALF OF NEXT WEEK. THE TROUGH WILL REACH THE HIGH PLAINS AND THE
MIDWEST BY SUNDAY AND SUBSEQUENTLY DEEPEN AS IT IS REINFORCED BY A
SERIES OF SUCCESSIVE SHORTWAVE IMPULSES ENTERING THE TROUGH FROM
WESTERN CANADA. BY TUESDAY BOTH THE ECMWF AND GFS ARE NOW CARVING
OUT A MASSIVE 500 MB TROUGH ACROSS MOST OF THE CONUS...WITH A
CENTRAL CLOSED LOW SOMEWHERE OVER THE UPPER MIDWEST. FOR OUR
FORECAST AREA THIS SCENARIO WILL TRANSLATE INTO A PROLONGED PERIOD
OF PRECIPITATION CHANCES...BEGINNING SOMETIME AROUND SUNDAY OR
SUNDAY NIGHT AND PERSISTING AT INTERVALS AT LEAST THROUGH TUESDAY.
HOWEVER...PRECIPITATION TYPE WILL BE HEAVILY DEPENDENT ON THE
LOCATION OF THE UPPER AND SURFACE LOW PRESSURE CENTERS AND THEIR
ASSOCIATED THERMAL PROFILES. CURRENT LONG RANGE MODEL SOLUTIONS
SUPPORT A FAIRLY LONG PERIOD OF RAIN WITH SNOW MORE LIMITED TO
NORTHERN IOWA AND LATER IN THE EVENT...LIKELY RESULTING IN LOW
SNOWFALL AMOUNTS. HOWEVER...WITH THE SYSTEM STILL FOUR OR FIVE
DAYS AWAY AND NOT EVEN ENTERING THE RAOB NETWORK UNTIL AROUND
FRIDAY...THE SOLUTIONS ARE HARDLY STABLE AND A WIDE RANGE OF
EVENTUAL OUTCOMES IS POSSIBLE SO THE FORECAST WILL LIKELY BE
FLUCTUATING IN THE COMING DAYS. ALL INTERESTS WITH TRAVEL PLANS
AROUND CHRISTMAS SHOULD CONTINUE TO MONITOR THESE TRENDS AND HOPE
THAT TEMPERATURES STAY WARM ENOUGH FOR THE PRECIPITATION TO FALL
PREDOMINANTLY AS RAIN.

&&

.AVIATION...17/06Z
ISSUED AT 1135 PM CST TUE DEC 16 2014

STRATUS BEGINNING TO ERODE FROM THE WEST AND THIS SHOULD CONTINUE
TO DIMINISH ACROSS THE FORECAST AREA OVERNIGHT WITH SURFACE RIDGE
APPROACHING. WILL SEE MAINLY VFR CONDITIONS ON WEDNESDAY INTO
WEDNESDAY NIGHT ALTHOUGH SOME MVFR CEILINGS MAY IMPACT THE NORTH
ON WEDNESDAY NEAREST THE UPPER LOW THAT WILL PASS EAST THROUGH THE
UPPER MIDWEST AND GREAT LAKES. SURFACE WINDS WILL REMAIN FROM THE
NORTHWEST BUT NOT NEARLY AS STRONG AS MONDAY.


&&

.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...SMALL
LONG TERM...LEE
AVIATION...COGIL



AREA FORECAST DISCUSSION

NWS JACKSON KY

 340 PM EST WED DEC 17 2014

.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 310 PM EST WED DEC 17 2014

19Z SFC ANALYSIS SHOWS HIGH PRESSURE STARTING TO MORE EFFECTIVELY
MOVE INTO THE AREA. THIS IS BEGINNING TO BREAK UP THE LOW LEVEL CLOUD
COVER ACROSS AT LEAST THE SOUTHERN HALF OF THE CWA. THESE CLOUDS HAVE
KEPT TEMPERATURES IN CHECK SO FAR TODAY WITH READINGS GENERALLY IN
THE MID TO UPPER 30S NORTH AND IN THE LOWER 40S IN THE SOUTHEAST
WHERE SOME EARLY SUNSHINE IS MAKING ITS PRESENCE FELT. DEWPOINTS HAVE
DRIED OUT THROUGH THE DAY AND ARE NOW IN THE UPPER 20S TO LOWER 30S.
WINDS HAVE BEEN RELATIVELY LIGHT GENERALLY FROM THE WEST AT 5 TO 10
KTS TODAY.

THE MODELS ARE NOW IN PRETTY GOOD AGREEMENT ALOFT THROUGH THE SHORT
TERM PORTION OF THE FORECAST. THEY ALL DEPICT THE CLOSED...BUT
PROGRESSIVE...UPPER LOW THAT WILL SKIRT EAST THROUGH THE LOWER GREAT
LAKES THIS EVENING AND OVERNIGHT. A BRIEF PERIOD OF RIDGING WILL
FOLLOW INTO THURSDAY MORNING FOR EASTERN KENTUCKY BEFORE A RATHER
DAMPENED WAVE MOVES THROUGH LATER IN THE DAY AND THAT NIGHT WITH
SOME WEAK MID-LEVEL ENERGY FLOWING INTO THE CONFLUENCE ZONE EAST OF
THE AREA. WITH THE GENERAL MODEL AGREEMENT HAVE FOLLOWED THE HIGH
RESOLUTION NAM12 AND HRRR MOST CLOSELY FOR WEATHER DETAILS.

SENSIBLE WEATHER WILL FEATURE A BRIEF TIME OF CLEARING THIS EVENING
AND INTO TONIGHT THAT SHOULD ALLOW FOR SOME DECENT RADIATIONAL
COOLING AND RIDGE TO VALLEY TEMPERATURE DIFFERENCES THROUGH MIDNIGHT.
THEREAFTER...HIGH AND MID LEVEL CLOUDS WILL RETURN TO THE AREA FROM
WEST TO EAST AND PUT A CAP ON THE COOLING...LIMITING FURTHER TERRAIN
DIFFERENCES FOR THE REST OF THE NIGHT. THESE CLOUDS WILL ATTEMPT TO
BRING SNOW TO THE SOUTHWESTERN PARTS OF THE AREA BEFORE DAWN...BUT IT
WILL HAVE TO OVERCOME THE DRYING TAKING PLACE ATTM. ACCORDINGLY...
HAVE UNDERCUT QPF AND POPS FROM THE NAM/MET FOR LATE TONIGHT INTO
THURSDAY MORNING. THE AREA OF LOW PRESSURE RESPONSIBLE FOR THE PCPN
THREAT WILL DAMPEN THROUGH THE MORNING AND FADE OUT BY AFTERNOON. FOR
THIS...HAVE LIMITED THE PCPN THREAT TO JUST FLURRIES AND SPRINKLES
FOR THE SECOND HALF OF THE DAY. ADDITIONAL MOISTURE WILL PASS BY TO
THE NORTH LATER THAT EVENING AND A FEW FLURRIES WILL BE POSSIBLE FROM
THIS ALONG WITH ANOTHER COOL NIGHT.

AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR THE T/TD/WIND
GRIDS FOR THE FIRST 20 HOURS OR SO BEFORE POPULATING WITH THE
SUPERBLEND THEREAFTER. MINOR ADJUSTMENTS WERE MADE FOR TERRAIN
EFFECTS BOTH TONIGHT AND THURSDAY NIGHT. AS FOR POPS...ENDED UP A BIT
UNDER THE MET NUMBERS AND CLOSER TO THE DRIER MAV ONES FOR TONIGHT
AND THURSDAY GIVEN THE DRY AIR THAT WILL BE IN PLACE.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 340 PM EST WED DEC 17 2014

FORECAST MODELS ARE IN GOOD AGREEMENT ON AN ACTIVE WEATHER PATTERN
WITH AT LEAST TWO SYSTEMS TO AFFECT US THROUGH THE PERIOD.

THE FIRST STORM OVER THE WEEKEND CONTINUES TO LOOK RATHER WEAK. A
LIGHT RAIN/SNOW MIX WILL MOVE INTO THE AREA OVERNIGHT FRIDAY NIGHT.
THIS WILL CHANGE TO ALL RAIN DURING THE DAY ON SATURDAY...FOLLOWED
BY PERHAPS BY A LITTLE MORE SNOW AS THE PRECIPITATION ENDS SATURDAY
NIGHT. THERE IS JUST NOT A LOT OF COLD AIR IN PLACE AND
PRECIPITATION LOOKS LIGHT SO ANY SNOW ACCUMULATIONS WILL BE VERY
LIGHT WITH THIS SYSTEM...IF ANY OCCUR AT ALL.

A MUCH MORE IMPRESSIVE STORM SYSTEM IS SHOWING UP IN THE COMPUTER
MODELS FOR THE MIDDLE OF NEXT WEEK...WITH DECENT AGREEMENT ON AN
IMPACTFUL SYSTEM JUST IN TIME FOR PEAK HOLIDAY TRAVEL. AN UPPER
LEVEL TROUGH WILL DIG IN OVER THE PLAINS EARLY IN THE WEEK AND
BECOME NEGATIVELY TILTED OVER THE OHIO VALLEY MID WEEK. THIS CAUSES
EXPLOSIVE DEEPENING OF A SURFACE LOW PRESSURE WHICH IS PROGGED TO
DEVELOP AND TRACK OVER US OR VERY CLOSE TO US ON ITS WAY NORTH TO
THE GREAT LAKES. THIS SYSTEM IS STILL WAY TOO FAR OUT IN THE FUTURE
TO PINPOINT EXACTLY WHAT TYPE OF WEATHER WE WILL BE DEALING
WITH...BUT RAIN...WIND AND SNOW ARE ALL ON THE TABLE FROM TUESDAY
THROUGH WEDNESDAY...AND POTENTIALLY BEYOND.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 130 PM EST WED DEC 17 2014

DRIER AIR IS FINALLY STARTING TO MAKE IT TO THE SURFACE ACROSS EAST
KENTUCKY AND THIS WILL BRING THE LIGHT PCPN TO END...BUT BKN MVFR
CLOUDS WILL CONTINUE FOR AT LEAST A COUPLE OF HOURS. THESE SHOULD
BREAK UP FROM SOUTHWEST TO NORTHEAST. HOW SUCCESSFULLY IS STILL IN
QUESTION. ALSO...HIGH CLOUDS WILL START BUILDING IN OVER THE AREA
FROM THE WEST AFTER MIDNIGHT...SO ANY REAL CLEARING WILL LIKELY BE
SHORT LIVED. THIS NEXT SYSTEM DOES BRING THE POTENTIAL FOR SOME
LIGHT SNOW LATE TONIGHT/EARLY THURSDAY MORNING FOR MAINLY KSME AND
KLOZ. HOWEVER...LOW LEVEL DRY AIR LOOKS LIKE IT WILL MAKE IT HARD FOR
THE PCPN TO ACTUALLY REACH THE SURFACE. THEREFORE...CONFIDENCE
REMAINS TOO LOW FOR MENTIONING IN TAFS AT THIS TIME. FINALLY...STRONG
WINDS ALOFT MAY BE OF CONCERN OVER THE NEXT 24 HOURS. AN UPPER LEVEL
JET IS DEPARTING THE AREA TAKING ITS STRONG WESTERLY IN THE MID AND
UPPER LEVELS AWAY FROM EASTERN KENTUCKY. SFC HIGH PRESSURE AND THE
STRONG SUBSIDENCE INVERSION STILL IN PLACE WILL KEEP WINDS RELATIVELY
LIGHT ACROSS THE FA THROUGH MIDDAY THURSDAY.


&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...GREIF
LONG TERM...ABE
AVIATION...GREIF







AREA FORECAST DISCUSSION...UPDATED

NWS JACKSON KY

 310 PM EST WED DEC 17 2014

.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 310 PM EST WED DEC 17 2014

19Z SFC ANALYSIS SHOWS HIGH PRESSURE STARTING TO MORE EFFECTIVELY
MOVE INTO THE AREA. THIS IS BEGINNING TO BREAK UP THE LOW LEVEL CLOUD
COVER ACROSS AT LEAST THE SOUTHERN HALF OF THE CWA. THESE CLOUDS HAVE
KEPT TEMPERATURES IN CHECK SO FAR TODAY WITH READINGS GENERALLY IN
THE MID TO UPPER 30S NORTH AND IN THE LOWER 40S IN THE SOUTHEAST
WHERE SOME EARLY SUNSHINE IS MAKING ITS PRESENCE FELT. DEWPOINTS HAVE
DRIED OUT THROUGH THE DAY AND ARE NOW IN THE UPPER 20S TO LOWER 30S.
WINDS HAVE BEEN RELATIVELY LIGHT GENERALLY FROM THE WEST AT 5 TO 10
KTS TODAY.

THE MODELS ARE NOW IN PRETTY GOOD AGREEMENT ALOFT THROUGH THE SHORT
TERM PORTION OF THE FORECAST. THEY ALL DEPICT THE CLOSED...BUT
PROGRESSIVE...UPPER LOW THAT WILL SKIRT EAST THROUGH THE LOWER GREAT
LAKES THIS EVENING AND OVERNIGHT. A BRIEF PERIOD OF RIDGING WILL
FOLLOW INTO THURSDAY MORNING FOR EASTERN KENTUCKY BEFORE A RATHER
DAMPENED WAVE MOVES THROUGH LATER IN THE DAY AND THAT NIGHT WITH
SOME WEAK MID-LEVEL ENERGY FLOWING INTO THE CONFLUENCE ZONE EAST OF
THE AREA. WITH THE GENERAL MODEL AGREEMENT HAVE FOLLOWED THE HIGH
RESOLUTION NAM12 AND HRRR MOST CLOSELY FOR WEATHER DETAILS.

SENSIBLE WEATHER WILL FEATURE A BRIEF TIME OF CLEARING THIS EVENING
AND INTO TONIGHT THAT SHOULD ALLOW FOR SOME DECENT RADIATIONAL
COOLING AND RIDGE TO VALLEY TEMPERATURE DIFFERENCES THROUGH MIDNIGHT.
THEREAFTER...HIGH AND MID LEVEL CLOUDS WILL RETURN TO THE AREA FROM
WEST TO EAST AND PUT A CAP ON THE COOLING...LIMITING FURTHER TERRAIN
DIFFERENCES FOR THE REST OF THE NIGHT. THESE CLOUDS WILL ATTEMPT TO
BRING SNOW TO THE SOUTHWESTERN PARTS OF THE AREA BEFORE DAWN...BUT IT
WILL HAVE TO OVERCOME THE DRYING TAKING PLACE ATTM. ACCORDINGLY...
HAVE UNDERCUT QPF AND POPS FROM THE NAM/MET FOR LATE TONIGHT INTO
THURSDAY MORNING. THE AREA OF LOW PRESSURE RESPONSIBLE FOR THE PCPN
THREAT WILL DAMPEN THROUGH THE MORNING AND FADE OUT BY AFTERNOON. FOR
THIS...HAVE LIMITED THE PCPN THREAT TO JUST FLURRIES AND SPRINKLES
FOR THE SECOND HALF OF THE DAY. ADDITIONAL MOISTURE WILL PASS BY TO
THE NORTH LATER THAT EVENING AND A FEW FLURRIES WILL BE POSSIBLE FROM
THIS ALONG WITH ANOTHER COOL NIGHT.

AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR THE T/TD/WIND
GRIDS FOR THE FIRST 20 HOURS OR SO BEFORE POPULATING WITH THE
SUPERBLEND THEREAFTER. MINOR ADJUSTMENTS WERE MADE FOR TERRAIN
EFFECTS BOTH TONIGHT AND THURSDAY NIGHT. AS FOR POPS...ENDED UP A BIT
UNDER THE MET NUMBERS AND CLOSER TO THE DRIER MAV ONES FOR TONIGHT
AND THURSDAY GIVEN THE DRY AIR THAT WILL BE IN PLACE.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 310 PM EST WED DEC 17 2014

THE LONG TERM DISCUSSION WILL BE ISSUED SHORTLY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 130 PM EST WED DEC 17 2014

DRIER AIR IS FINALLY STARTING TO MAKE IT TO THE SURFACE ACROSS EAST
KENTUCKY AND THIS WILL BRING THE LIGHT PCPN TO END...BUT BKN MVFR
CLOUDS WILL CONTINUE FOR AT LEAST A COUPLE OF HOURS. THESE SHOULD
BREAK UP FROM SOUTHWEST TO NORTHEAST. HOW SUCCESSFULLY IS STILL IN
QUESTION. ALSO...HIGH CLOUDS WILL START BUILDING IN OVER THE AREA
FROM THE WEST AFTER MIDNIGHT...SO ANY REAL CLEARING WILL LIKELY BE
SHORT LIVED. THIS NEXT SYSTEM DOES BRING THE POTENTIAL FOR SOME
LIGHT SNOW LATE TONIGHT/EARLY THURSDAY MORNING FOR MAINLY KSME AND
KLOZ. HOWEVER...LOW LEVEL DRY AIR LOOKS LIKE IT WILL MAKE IT HARD FOR
THE PCPN TO ACTUALLY REACH THE SURFACE. THEREFORE...CONFIDENCE
REMAINS TOO LOW FOR MENTIONING IN TAFS AT THIS TIME. FINALLY...STRONG
WINDS ALOFT MAY BE OF CONCERN OVER THE NEXT 24 HOURS. AN UPPER LEVEL
JET IS DEPARTING THE AREA TAKING ITS STRONG WESTERLY IN THE MID AND
UPPER LEVELS AWAY FROM EASTERN KENTUCKY. SFC HIGH PRESSURE AND THE
STRONG SUBSIDENCE INVERSION STILL IN PLACE WILL KEEP WINDS RELATIVELY
LIGHT ACROSS THE FA THROUGH MIDDAY THURSDAY.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...GREIF
LONG TERM...ABE
AVIATION...GREIF




AREA FORECAST DISCUSSION

NWS JACKSON KY

 127 AM EST WED DEC 17 2014

.UPDATE...
ISSUED AT 116 AM EST WED DEC 17 2014

WITHIN THE LAST COUPLE OF HOURS...DRIZZLE HAS PICKED UP SIGNIFICANTLY
ACROSS THE NORTHERN HALF OF THE CWA...TRANSITIONING TO MORE OF A
SCATTERED RAIN SHOWER EVENT WITH EMBEDDED AREAS OF DRIZZLE. THERE
DOES SEEM TO BE A BACK EDGE TO THIS HEAVIER PRECIP...WHICH IS
CURRENTLY MOVING EASTWARD INTO OUR CWA. AS SUCH...HEIGHTENED WORDING
FROM DRIZZLE TO SCATTERED RAIN SHOWERS...DIMINISHING FROM WEST TO
EAST OVER THE NEXT 6 HOURS AND TRANSITIONING BACK TO DRIZZLE WITH A
FEW ISOLATED AREAS OF HEAVIER RAINFALL POSSIBLE THROUGH 12Z. ALSO
FRESHENED UP THE NEAR-TERM FORECAST FOR TEMPS...DEW POINTS...AND
WINDS...BASED ON THE 5Z OBSERVATIONS.

UPDATE ISSUED AT 1105 PM EST TUE DEC 16 2014

DRIZZLE AND SOME EMBEDDED SHOWERS CONTINUE ACROSS EASTERN KENTUCKY.
THE HOURLY POPS HAVE BEEN INCREASED TO ISOLATED FOR THE NORTH AND
EAST INTO EARLY ON THU. HOURLY TEMPERATURES HAVE BEEN FRESHENED UP
BASED ON RECENT OBSERVATIONS. NO SIGNIFICANT CHANGES WERE NEEDED AT
THIS TIME.

UPDATE ISSUED AT 745 PM EST TUE DEC 16 2014

HOURLY GRIDS HAVE BEEN UPDATED BASED ON RADAR AND OBSERVATION TRENDS.
THIS LED TO LOWERING TEMPERATURES IN THE HIGHEST TERRAIN INITIALLY
ABOVE 2500 FEET. MODEL PLAN VIEW DATA ALSO SUGGESTED SLIGHTLY LOWER
MIN T IN THE HIGHER TERRAIN NEAR BLACK MTN. RAIN SHOWERS CONTINUE
ACROSS THE EASTERN PART OF THE CWA...WITH SOME DRIZZLE FURTHER TO THE
WEST. MODEL DATA SUGGESTS SUFFICIENT MOISTURE FOR DRIZZLE TO LINGER
THROUGH THE NIGHT AND INTO EARLY ON WED. THE HIGHEST TERRAIN SHOULD
COOL ENOUGH FOR CHANCES OF FREEZING DRIZZLE ABOVE 2000 FEET. THIS
THREAT WILL BEGIN FIRST...IN THE NEXT HOUR OR TWO ON TOP OF BLACK MTN
AND THEN GRADUALLY SPREAD TO PINE MOUNTAIN AND POSSIBLY THE LOG
MOUNTAINS.

&&

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 315 PM EST TUE DEC 16 2014

19Z SFC ANALYSIS SHOWS A FAIRLY DEEP AREA OF LOW PRESSURE LIFTING
NORTHEAST THROUGH THE EASTERN GREAT LAKES. THE COLD FRONT ASSOCIATED
WITH THIS SYSTEM IS NOW THROUGH EASTERN KENTUCKY AND AS A RESULT
GUSTY WEST WINDS ARE BRINGING IN A COLDER AIR MASS. AS IT DOES SO...
IT IS ALSO GENERATING A SUBSTANTIAL AREA OF DRIZZLE AND LOWER CIGS.
TEMPERATURES VARY FROM THE LOW 40S WEST TO NEAR 50S EAST ACROSS THE
CWA WITH DEWPOINTS IN THE UPPER 30S TO LOWER 40S.

THE MODELS ARE IN DECENT ENOUGH AGREEMENT ALOFT THROUGH THE SHORT
TERM PORTION OF THE FORECAST AS THEY ALL DAMPEN OUT THE CURRENT
TROUGH OVER THE AREA WHILE ABSORBING IT INTO THE MAIN MID LEVEL LOW
OVER THE UPPER MIDWEST. THIS WILL KEEP FAST...WEST TO EAST...FLOW
ABOVE EASTERN KENTUCKY INTO THE DAY WEDNESDAY...THOUGH MODEL
DIFFERENCES START TO MAGNIFY BY DAWN. THE ECMWF IS SLOWER MOVING
THIS MIDWEST LOW EAST COMPARED TO THE GEM AND GFS WHICH WILL ALSO
SERVE TO KEEP OUR HEIGHTS SLIGHTLY SUPPRESSED INTO WEDNESDAY EVENING.
DESPITE THIS...THE PREFERRED ECMWF DOES NOT LAG IN BRINGING THE NEXT
BATCH OF ENERGY INTO THE REGION FROM A QUICK MOVING WAVE PASSING OUT
OF THE SOUTHERN PLAINS. THIS WILL SEEP INTO OUR SOUTHWEST PARTS BY
THURSDAY MORNING. FOR THE FORECAST...FOLLOWED A BLEND OF THE HIGHER
RESOLUTION HRRR AND NAM12 WITH SOME ADJUSTMENT TOWARD THE MAIN
FEATURES IN THE LATEST ECMWF.

A DREARY EVENING AND OVERNIGHT IS ANTICIPATED THROUGH EASTERN
KENTUCKY AS LOW CIGS AND DRIZZLE WILL DOMINATE UNDER A SUBSIDENCE
INVERSION...PARTICULARLY OVER THE NORTHERN HALF THE CWA. THERE IS A
CONCERN THAT THE HIGHER POINTS OF EASTERN KENTUCKY FALL TO
FREEZING...OR A COUPLE OF DEGREES BELOW...BY DAWN GIVEN THE CAA
OVERNIGHT. COMBINED WITH THE AREAS OF DRIZZLE STILL AROUND...THERE
WILL BE A THREAT OF FREEZING DRIZZLE GENERALLY ABOVE 2000 FEET. FOR
THIS...WILL ISSUE AN SPS FROM LATE TONIGHT INTO THURSDAY MORNING FOR
OUR SOUTHEASTERN-MOST COUNTIES WITH THAT HIGHER TERRAIN. THE LOW
CLOUDS WILL PROBABLY HOLD TOUGH INTO THE FIRST PART OF THE DAY
WEDNESDAY BUT THERE COULD BE SOME BREAKUP MAKING FOR A BRIEF PERIOD
OF SUNSHINE DURING THE AFTERNOON AHEAD OF THE NEXT BATCH OF HIGHER
CLOUDS DUE IN HERE LATER THAT EVENING. THESE NEXT CLOUDS WILL QUICKLY
INCREASE AND LOWER THROUGH THE NIGHT WITH EVEN SOME LIGHT RAIN OR
SNOW POSSIBLE BY DAWN THURSDAY...THOUGH TEMPERATURES WILL BE MILDER
THAN TONIGHT IN MOST PLACES.

USED THE BCCONSSHORT AS A STARTING POINT FOR THE T/TD/WIND GRIDS FOR
THE FIRST 20 HOURS BEFORE POPULATING WITH THE SUPERBLEND THEREAFTER.
THESE WERE THEN SUBJECTED TO MINOR ADJUSTMENTS FOR TERRAIN EFFECTS
MAINLY TONIGHT AND WEDNESDAY NIGHT. AS FOR POPS...ENDED UP JUST ABOVE
THE HIGHER MET MOS GUIDANCE TONIGHT GIVEN THE LOW QPF BUT MODERATE
POPS WITH EXTRA EMPHASIS ON DRIZZLE AS PTYPE. ALSO...FOR LATE
WEDNESDAY WENT A BIT HIGHER THEN GUIDANCE IN THE SOUTHWEST GIVEN THE
FAST FLOW REGIME.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 245 PM EST TUE DEC 16 2014

PROGRESSIVE PATTERN WILL CONTINUE THROUGH THE EXTENDED. THE PERIOD
WILL START AS A MID LEVEL TROUGH CROSSES INTO THE OHIO RIVER VALLEY
ON THURSDAY. MODELS HAVE TRENDED MORE AGGRESSIVE WITH THIS FEATURE
WITH THE 12Z SUITE OF MODELS WITH GFS EVEN SHOWING SOME MODEST LIFT
ABOVE 850MB. THE MAIN LIMITING FACTOR FOR PRECIPITATION ON THURSDAY
WILL BE THE LOW LEVEL DRY AIR. HOWEVER...GIVEN THE DEEP MOISTURE
STARTING AROUND 5KFT...THIS SHOULD BE ENOUGH TO AT LEAST WARRANT A
CHANCE OF MEASURABLE PRECIPITATION REACHING THE GROUND.
HOWEVER...THIS PRECIPITATION MAY DRY UP AS IT TRIES TO PUSH
NORTHWARD THROUGH THE DAY. THUS...PLAN TO GO WITH CHANCE POPS ACROSS
THE SOUTH...TRAILING OFF TO SLIGHT CHANCE IN THE NORTH. ALL OF THIS
PRECIPITATION AS EXPECTED WILL REMAIN LIGHT...BUT SOME SNOWFLAKES
COULD MIX IN AT TIMES THROUGH THE DAY. HIGH PRESSURE WILL PROVIDE
DRY WEATHER THURSDAY NIGHT THROUGH FRIDAY.

THE WEATHER TURNS MORE INTERESTING BY FRIDAY NIGHT THROUGH SATURDAY
AS A SOUTHERN STREAM SHORTWAVE PUSHES EAST ACROSS THE SOUTHERN TIER
OF THE US. THIS SYSTEM IS NOT EXPECTED TO GET MUCH HELP FROM THE
NORTHERN STREAM...AND THUS...NOT MUCH COLD AIR IS EXPECTED TO GET
WORKED INTO THIS SYSTEM. THIS FACT...COMBINED WITH A WEAKENING AREA
OF LOW PRESSURE TRACKING ACROSS THE GULF COAST STATES WILL LIKELY
YIELD VERY LITTLE SNOW POTENTIAL. HOWEVER...WE ARE ON THE NORTH SIDE
OF THIS SYSTEM...WHICH WOULD BE THE BEST SPOT FOR ANY SNOW.
PRECIPITATION IS EXPECTED TO SPREAD INTO THE AREA LATE FRIDAY NIGHT
AND CONTINUE THROUGH SATURDAY. BEST SNOW POTENTIAL MAY BE AT THE
ONSET FRIDAY NIGHT...BUT AGAIN...PRECIPITATION RATES MAY BE FAIRLY
LIMITED...KEEPING SNOW AMOUNTS FROM BEING ALL THAT HIGH. IN
FACT...WE COULD SEE A MIX OF RAIN/SNOW RIGHT THROUGH SATURDAY WITH
VERY LITTLE SNOW ACCUMULATION FOR MUCH OF THE AREA. THE ECMWF
REMAINS THE COLDER OF THE MODELS SUGGESTING BETTER SNOW
POTENTIAL...WHILE THE GFS HAS MAINTAINED ITS ALL RAIN FORECAST.
GOING WITH A COMPROMISE ON HIGHS ON SATURDAY WOULD BE TEMPERATURES
AROUND 40 BY THE AFTERNOON ACROSS MUCH OF THE AREA. ITS POSSIBLE
SOME COOLER READINGS IN THE 30S COULD KEEP MORE SNOW GOING A BIT
LONGER ACROSS THE NORTHERN PORTION OF THE AREA...BUT WITH WEAK
PRECIP RATES...COMBINED WITH ABOVE FREEZING TEMPERATURES...SHOULD
REALLY CUT INTO ANY SNOWFALL POTENTIAL EVEN WITH THE COLDER ECMWF
SOLUTION. PRECIPITATION WILL WIND DOWN BY SATURDAY NIGHT GOING OVER
TO A PERIOD OF LIKELY DRIZZLE.

DRY WEATHER WILL RETURN FOR SUNDAY AND PERSIST INTO THE EARLY PART
OF NEXT WEEK. TEMPERATURES ARE EXPECTED TO REMAIN FAIRLY SEASONABLE
THROUGH THE END OF THE FORECAST PERIOD.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 127 AM EST WED DEC 17 2014

WHILE AREAS OF DRIZZLE ARE ONGOING ACROSS MUCH OF EASTERN KY...THE
NORTHEAST PORTION OF THE STATE /GENERALLY AREAS NORTH OF THE MOUNTAIN
PARKWAY/... HAVE ACTUALLY SEEN A INCREASE FROM DRIZZLE TO LIGHT RAIN
SHOWERS. EXPECT THIS RAIN TO HAVE LITTLE DIFFERENCE IN IMPACTS TO
THAT OF THE DRIZZLE...SO WILL JUST CONTINUE WITH DRIZZLE MENTION AT
THIS TIME IN TAFS...ESPECIALLY GIVEN THAT THE RAIN SHOWERS SHOULD
TAPER OFF AT KSYM...KJKL...AND KSJS OVER THE NEXT COUPLE HOURS.
MEANWHILE...CIGS SHOULD REMAIN BETWEEN IFR AND MVFR THROUGH THE
REMAINDER OF THE NIGHT...THEN MVFR THROUGH A MAJORITY OF THE DAY
TOMORROW...AT LEAST UNTIL DRY AIR IS FINALLY ABLE TO MIX DOWN TO THE
SURFACE...CUTTING OFF DRIZZLE POTENTIAL...AND SLOWLY BREAKING THE LOW
CLOUD DECK. LATEST GFS FORECAST SOUNDINGS ARE SHOWING THIS OCCURRING
SOMETIME BETWEEN 18 AND 21Z...WHILE THE NAM TRIES TO HOLD ON TO THE
MOISTURE A BIT LONGER. LEANED MORE TOWARDS THE GFS SOLUTION AT THIS
TIME.


&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...JMW
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...JMW






AREA FORECAST DISCUSSION...UPDATED

NWS JACKSON KY

 1115 PM EST TUE DEC 16 2014

.UPDATE...
ISSUED AT 1105 PM EST TUE DEC 16 2014

DRIZZLE AND SOME EMBEDDED SHOWERS CONTINUE ACROSS EASTERN KENTUCKY.
THE HOURLY POPS HAVE BEEN INCREASED TO ISOLATED FOR THE NORTH AND
EAST INTO EARLY ON THU. HOURLY TEMPERATURES HAVE BEEN FRESHENED UP
BASED ON RECENT OBSERVATIONS. NO SIGNIFICANT CHANGES WERE NEEDED AT
THIS TIME.

UPDATE ISSUED AT 745 PM EST TUE DEC 16 2014

HOURLY GRIDS HAVE BEEN UPDATED BASED ON RADAR AND OBSERVATION TRENDS.
THIS LED TO LOWERING TEMPERATURES IN THE HIGHEST TERRAIN INITIALLY
ABOVE 2500 FEET. MODEL PLAN VIEW DATA ALSO SUGGESTED SLIGHTLY LOWER
MIN T IN THE HIGHER TERRAIN NEAR BLACK MTN. RAIN SHOWERS CONTINUE
ACROSS THE EASTERN PART OF THE CWA...WITH SOME DRIZZLE FURTHER TO THE
WEST. MODEL DATA SUGGESTS SUFFICIENT MOISTURE FOR DRIZZLE TO LINGER
THROUGH THE NIGHT AND INTO EARLY ON WED. THE HIGHEST TERRAIN SHOULD
COOL ENOUGH FOR CHANCES OF FREEZING DRIZZLE ABOVE 2000 FEET. THIS
THREAT WILL BEGIN FIRST...IN THE NEXT HOUR OR TWO ON TOP OF BLACK MTN
AND THEN GRADUALLY SPREAD TO PINE MOUNTAIN AND POSSIBLY THE LOG
MOUNTAINS.

&&

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 315 PM EST TUE DEC 16 2014

19Z SFC ANALYSIS SHOWS A FAIRLY DEEP AREA OF LOW PRESSURE LIFTING
NORTHEAST THROUGH THE EASTERN GREAT LAKES. THE COLD FRONT ASSOCIATED
WITH THIS SYSTEM IS NOW THROUGH EASTERN KENTUCKY AND AS A RESULT
GUSTY WEST WINDS ARE BRINGING IN A COLDER AIR MASS. AS IT DOES SO...
IT IS ALSO GENERATING A SUBSTANTIAL AREA OF DRIZZLE AND LOWER CIGS.
TEMPERATURES VARY FROM THE LOW 40S WEST TO NEAR 50S EAST ACROSS THE
CWA WITH DEWPOINTS IN THE UPPER 30S TO LOWER 40S.

THE MODELS ARE IN DECENT ENOUGH AGREEMENT ALOFT THROUGH THE SHORT
TERM PORTION OF THE FORECAST AS THEY ALL DAMPEN OUT THE CURRENT
TROUGH OVER THE AREA WHILE ABSORBING IT INTO THE MAIN MID LEVEL LOW
OVER THE UPPER MIDWEST. THIS WILL KEEP FAST...WEST TO EAST...FLOW
ABOVE EASTERN KENTUCKY INTO THE DAY WEDNESDAY...THOUGH MODEL
DIFFERENCES START TO MAGNIFY BY DAWN. THE ECMWF IS SLOWER MOVING
THIS MIDWEST LOW EAST COMPARED TO THE GEM AND GFS WHICH WILL ALSO
SERVE TO KEEP OUR HEIGHTS SLIGHTLY SUPPRESSED INTO WEDNESDAY EVENING.
DESPITE THIS...THE PREFERRED ECMWF DOES NOT LAG IN BRINGING THE NEXT
BATCH OF ENERGY INTO THE REGION FROM A QUICK MOVING WAVE PASSING OUT
OF THE SOUTHERN PLAINS. THIS WILL SEEP INTO OUR SOUTHWEST PARTS BY
THURSDAY MORNING. FOR THE FORECAST...FOLLOWED A BLEND OF THE HIGHER
RESOLUTION HRRR AND NAM12 WITH SOME ADJUSTMENT TOWARD THE MAIN
FEATURES IN THE LATEST ECMWF.

A DREARY EVENING AND OVERNIGHT IS ANTICIPATED THROUGH EASTERN
KENTUCKY AS LOW CIGS AND DRIZZLE WILL DOMINATE UNDER A SUBSIDENCE
INVERSION...PARTICULARLY OVER THE NORTHERN HALF THE CWA. THERE IS A
CONCERN THAT THE HIGHER POINTS OF EASTERN KENTUCKY FALL TO
FREEZING...OR A COUPLE OF DEGREES BELOW...BY DAWN GIVEN THE CAA
OVERNIGHT. COMBINED WITH THE AREAS OF DRIZZLE STILL AROUND...THERE
WILL BE A THREAT OF FREEZING DRIZZLE GENERALLY ABOVE 2000 FEET. FOR
THIS...WILL ISSUE AN SPS FROM LATE TONIGHT INTO THURSDAY MORNING FOR
OUR SOUTHEASTERN-MOST COUNTIES WITH THAT HIGHER TERRAIN. THE LOW
CLOUDS WILL PROBABLY HOLD TOUGH INTO THE FIRST PART OF THE DAY
WEDNESDAY BUT THERE COULD BE SOME BREAKUP MAKING FOR A BRIEF PERIOD
OF SUNSHINE DURING THE AFTERNOON AHEAD OF THE NEXT BATCH OF HIGHER
CLOUDS DUE IN HERE LATER THAT EVENING. THESE NEXT CLOUDS WILL QUICKLY
INCREASE AND LOWER THROUGH THE NIGHT WITH EVEN SOME LIGHT RAIN OR
SNOW POSSIBLE BY DAWN THURSDAY...THOUGH TEMPERATURES WILL BE MILDER
THAN TONIGHT IN MOST PLACES.

USED THE BCCONSSHORT AS A STARTING POINT FOR THE T/TD/WIND GRIDS FOR
THE FIRST 20 HOURS BEFORE POPULATING WITH THE SUPERBLEND THEREAFTER.
THESE WERE THEN SUBJECTED TO MINOR ADJUSTMENTS FOR TERRAIN EFFECTS
MAINLY TONIGHT AND WEDNESDAY NIGHT. AS FOR POPS...ENDED UP JUST ABOVE
THE HIGHER MET MOS GUIDANCE TONIGHT GIVEN THE LOW QPF BUT MODERATE
POPS WITH EXTRA EMPHASIS ON DRIZZLE AS PTYPE. ALSO...FOR LATE
WEDNESDAY WENT A BIT HIGHER THEN GUIDANCE IN THE SOUTHWEST GIVEN THE
FAST FLOW REGIME.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 245 PM EST TUE DEC 16 2014

PROGRESSIVE PATTERN WILL CONTINUE THROUGH THE EXTENDED. THE PERIOD
WILL START AS A MID LEVEL TROUGH CROSSES INTO THE OHIO RIVER VALLEY
ON THURSDAY. MODELS HAVE TRENDED MORE AGGRESSIVE WITH THIS FEATURE
WITH THE 12Z SUITE OF MODELS WITH GFS EVEN SHOWING SOME MODEST LIFT
ABOVE 850MB. THE MAIN LIMITING FACTOR FOR PRECIPITATION ON THURSDAY
WILL BE THE LOW LEVEL DRY AIR. HOWEVER...GIVEN THE DEEP MOISTURE
STARTING AROUND 5KFT...THIS SHOULD BE ENOUGH TO AT LEAST WARRANT A
CHANCE OF MEASURABLE PRECIPITATION REACHING THE GROUND.
HOWEVER...THIS PRECIPITATION MAY DRY UP AS IT TRIES TO PUSH
NORTHWARD THROUGH THE DAY. THUS...PLAN TO GO WITH CHANCE POPS ACROSS
THE SOUTH...TRAILING OFF TO SLIGHT CHANCE IN THE NORTH. ALL OF THIS
PRECIPITATION AS EXPECTED WILL REMAIN LIGHT...BUT SOME SNOWFLAKES
COULD MIX IN AT TIMES THROUGH THE DAY. HIGH PRESSURE WILL PROVIDE
DRY WEATHER THURSDAY NIGHT THROUGH FRIDAY.

THE WEATHER TURNS MORE INTERESTING BY FRIDAY NIGHT THROUGH SATURDAY
AS A SOUTHERN STREAM SHORTWAVE PUSHES EAST ACROSS THE SOUTHERN TIER
OF THE US. THIS SYSTEM IS NOT EXPECTED TO GET MUCH HELP FROM THE
NORTHERN STREAM...AND THUS...NOT MUCH COLD AIR IS EXPECTED TO GET
WORKED INTO THIS SYSTEM. THIS FACT...COMBINED WITH A WEAKENING AREA
OF LOW PRESSURE TRACKING ACROSS THE GULF COAST STATES WILL LIKELY
YIELD VERY LITTLE SNOW POTENTIAL. HOWEVER...WE ARE ON THE NORTH SIDE
OF THIS SYSTEM...WHICH WOULD BE THE BEST SPOT FOR ANY SNOW.
PRECIPITATION IS EXPECTED TO SPREAD INTO THE AREA LATE FRIDAY NIGHT
AND CONTINUE THROUGH SATURDAY. BEST SNOW POTENTIAL MAY BE AT THE
ONSET FRIDAY NIGHT...BUT AGAIN...PRECIPITATION RATES MAY BE FAIRLY
LIMITED...KEEPING SNOW AMOUNTS FROM BEING ALL THAT HIGH. IN
FACT...WE COULD SEE A MIX OF RAIN/SNOW RIGHT THROUGH SATURDAY WITH
VERY LITTLE SNOW ACCUMULATION FOR MUCH OF THE AREA. THE ECMWF
REMAINS THE COLDER OF THE MODELS SUGGESTING BETTER SNOW
POTENTIAL...WHILE THE GFS HAS MAINTAINED ITS ALL RAIN FORECAST.
GOING WITH A COMPROMISE ON HIGHS ON SATURDAY WOULD BE TEMPERATURES
AROUND 40 BY THE AFTERNOON ACROSS MUCH OF THE AREA. ITS POSSIBLE
SOME COOLER READINGS IN THE 30S COULD KEEP MORE SNOW GOING A BIT
LONGER ACROSS THE NORTHERN PORTION OF THE AREA...BUT WITH WEAK
PRECIP RATES...COMBINED WITH ABOVE FREEZING TEMPERATURES...SHOULD
REALLY CUT INTO ANY SNOWFALL POTENTIAL EVEN WITH THE COLDER ECMWF
SOLUTION. PRECIPITATION WILL WIND DOWN BY SATURDAY NIGHT GOING OVER
TO A PERIOD OF LIKELY DRIZZLE.

DRY WEATHER WILL RETURN FOR SUNDAY AND PERSIST INTO THE EARLY PART
OF NEXT WEEK. TEMPERATURES ARE EXPECTED TO REMAIN FAIRLY SEASONABLE
THROUGH THE END OF THE FORECAST PERIOD.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 735 PM EST TUE DEC 16 2014

RAIN SHOWERS WILL GRADUALLY TAPER TO DRIZZLE DURING THE FIRST 6 HOURS
OF THE PERIOD NEAR...WHILE AREAS OF DRIZZLE ARE ANTICIPATED FURTHER
TO THE WEST. IN FACT...FORECAST SOUNDINGS AND TIME HEIGHTS CONTINUE
TO INDICATE A STRONG SUBSIDENCE INVERSION BEHIND THE FRONT...WITH LOW
LEVEL MOISTURE TRAPPED INTO AT LEAST THE 12Z TO 18Z PERIOD. THIS
WILL LEAD TO LOWERING CIGS LIKELY DOWN INTO THE IFR RANGE AT ALL TAF
STIES AT TIMES...WITH THE DRIZZLE POTENTIAL LINGERING.


&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...JP
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...JP







AREA FORECAST DISCUSSION

NWS DETROIT/PONTIAC MI

 746 PM EST THU DEC 18 2014

.UPDATE...

RECENT RADAR SHOWING A DEFINITIVE UPTICK IN A DEFINED STRIPE OF
FREEZING DRIZZLE...PERHAPS ARGUABLY CLOSER TO FREEZING RAIN GIVEN
THE RETURNS...NOW SHIFTING THROUGH SOUTHERN LIVINGSTON/NORTHERN
WASHTENAW. THIS FEATURE REMAINS ANCHORED WITHIN A LINEAR AXIS OF
ENHANCED LOW LEVEL CONVERGENCE ACCOMPANYING THE PASSAGE OF A
SFC-850 MB TROUGH. 18Z NAM AND RECENT RAP GUIDANCE SUGGEST THIS
FEATURE WILL SLOWLY TRANSLATE SOUTHWARD OVER THE NEXT SEVERAL
HOURS...EFFECTIVELY SUSTAINING A FAVORABLE ENVIRONMENT FOR
MAINTENANCE OF THIS ONGOING LIGHT PRECIPITATION. POCKETS OF LIGHT
FREEZING DRIZZLE MIXED WITH SOME SNOWFLAKES WILL CONTINUE
ELSEWHERE SOUTH OF I-69 THROUGH ROUGHLY THE MIDNIGHT
WINDOW...THEREAFTER A LOSS OF MOISTURE DEPTH THROUGH THE BASE OF
THE INVERSION LAYER AS POST-TROUGH WINDS FLIP TO NORTHERLY SHOULD
BRING A NORTH TO SOUTH DIMINISHING TREND. THE GOING CONDITIONS IN
LIVINGSTON/WASHTENAW LIKELY CLOSING IN ON THE EDGE OF A VERY
SHORT FUSED ADVISORY HEADLINE. CALLS TO BOTH COUNTIES INDICATE
SLICK SPOTS ON SOME BRIDGES/OVERPASSES WITH ASSOCIATED SPINOUTS.
THIS BAND DOES APPEAR TRANSIENT ENOUGH AND OF SHORT ENOUGH
DURATION AT THIS TIME TO HOLD TIGHT IN HANDLING THE SITUATION
WITH SPECIAL WEATHER STATEMENTS /SPSDTX/...BUT WILL CONTINUE TO
MONITOR.

&&

.AVIATION...ISSUED 641 PM EST THU DEC 18 2014

//DISCUSSION...

DEEP PLUME OF LOW LEVEL MOISTURE TUCKED BENEATH A STRONG INVERSION
WILL HOLD FIRM TONIGHT.  RECENT OBSERVATIONS AND RADAR DATA CONTINUE
TO DISPLAY A COMBINATION OF LIGHT FREEZING DRIZZLE AND SNOWFLAKES
WITHIN THE RESULTANT LOW STRATUS FIELD.  THE OVERALL COVERAGE PER
LATEST TRENDS DO SUPPORT A TEMPO INCLUSION PRIOR TO MIDNIGHT FROM
FLINT SOUTHWARD.   CEILINGS AT FNT/PTK WILL FLUCTUATE WITHIN IFR/LOW
MVFR THROUGH THIS TIME...LOWER MVFR ELSEWHERE.  DRIER AIR WILL BEGIN
TO ERODE THIS MOIST LAYER FROM ABOVE THROUGH THE EARLY MORNING
PERIOD.  THIS WILL BRING A DIMINISHING TREND TO THE LIGHT
PRECIPITATION COVERAGE...ALTHOUGH THE EXISTING MVFR STRATUS WILL
LIKELY STRUGGLE TO SCATTER UNTIL WELL INTO FRIDAY.

FOR DTW...THERE WILL CONTINUE TO BE THE POTENTIAL FOR A LIGHT
MIXTURE OF FREEZING DRIZZLE AND SNOW EARLY TONIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE CEILINGS REMAIN BELOW 5000 FT THROUGH FRIDAY
  MORNING.

* HIGH CONFIDENCE THAT PRECIPITATION TYPE WILL BE A MIXTURE OF LIGHT
  FREEZING DRIZZLE AND SNOW THROUGH MIDNIGHT.

&&

.PREV DISCUSSION...ISSUED 355 PM EST THU DEC 18 2014

SHORT TERM...TONIGHT

FREEZING DRIZZLE AND LIGHT SNOW ACROSS SOUTHEAST MICHIGAN IS SLOWLY
BECOMING LESS WIDESPREAD AS THE AFTERNOON PROGRESSES. THE MAIN
CONCERN FOR TONIGHT WILL BE TIMING THE ENDING OF THE FREEZING
DRIZZLE AND WHETHER CLOUDS WILL STICK AROUND. WHILE CURRENT
SATELLITE IMAGERY IS SHOWING DRIER AIR SLOWLY PROGRESSING SOUTHWARD
OUT OF CANADA...PROGRESSION IS REALLY SLOW AND CURRENTLY NOT
ANTICIPATING THE DRY SURGE TO REACH SOUTHEAST MICHIGAN UNTIL CLOSER
TO DAYBREAK FRIDAY MORNING. WITH THE LOW LEVEL MOISTURE STICKING
AROUND OVERNIGHT...LOW LEVEL STRATUS IS EXPECTED TO REMAIN OVER THE
CWA. THE CLOUDS WILL KEEP TEMPERATURES FROM DROPPING TOO MUCH
OVERNIGHT AND HAVE THEREFORE OPTED TO SIDE ON THE WARMER SIDE OF
MODEL GUIDANCE FOR LOWS. EXPECT MID 20S ACROSS THE METRO DETROIT
AREA AND LOW TO MID 20S FOR THE REST OF THE CWA.

IN ADDITION...WHILE DRIZZLE IS DIMINISHING THE FORECASTED STRATUS
COULD RE-INITIATE DRIZZLE FOR THE EARLY PART OF THE EVENING. CURRENT
MODEL SOUNDINGS SHOW A WELL SATURATED BOUNDARY LAYER WITH LIGHT
WINDS OVER SOUTHEAST MICHIGAN THROUGH MOST OF THURSDAY EVENING WHICH
COULD HELP IN THE RE-DEVELOPMENT OF LIGHT DRIZZLE. AS TEMPERATURES
FALL BELOW FREEZING AFTER SUNSET...THE DRIZZLE COULD BECOME FREEZING
DRIZZLE AND MIX WITH SNOW ONCE AGAIN. HOWEVER...CONFIDENCE IN THIS
OCCURRING IS LOW AT THIS FORECAST ISSUANCE AND HAVE ONLY INCLUDED
FREEZING DRIZZLE IN THE FORECAST THROUGH 00Z /7PM/ THURSDAY. WILL
HAVE TO MONITOR OVER THE NEXT SEVERAL HOURS TO SEE IF DRIZZLE STARTS
TO DEVELOP.

LONG TERM...FRIDAY THROUGH WEDNESDAY

THE UPPER LEVEL PATTERN OVER THE UPPER MIDWEST AND GREAT LAKES
STATES WILL DEAMPLIFY TO THE POINT THAT PSEUDO ZONAL FLOW WILL BE
THE PRIMARY SETUP THROUGH MUCH OF THE UPCOMING WEEKEND. THE MAIN
WESTERLY JET AXIS WILL RESIDE OVER THE SOUTHEASTERN UNITED STATES
WITH VERY NOISY SHORTWAVE ENERGY PASSING WITHIN A FADING MIDLEVEL
COL STRUCTURE. HIGH COLUMN STABILITY SEEMS TO BE THE PRIMARY DRIVER
OF A SURFACE ANTICYCLONE THAT WILL PASS DIRECTLY THROUGH
SOUTHEASTERN MICHIGAN. DEAMPLIFIED FLOW WEAK SHORTWAVE ENERGY AND
RESULTS IN VERY QUIET WEATHER THAT MAINTAINS A STATUS QUO FROM A
TEMPERATURE AND PRECIPITATION PERSPECTIVE.

THERE WILL STILL BE SOME FORECAST DIFFICULTY IN THE EXPECTED
PATTERN...PRIMARILY THAT OF CLOUDS AND CLOUD TRENDS. MODEL DATA IS
VERY AGGRESSIVE WITH A SOUTHWARD PUSH OF DRY AIR LATE
TONIGHT...MAKING INROADS OVER MANY AREAS PRIOR TO SUNRISE. PATTERN
RECOGNITION AND OBSERVATIONAL DATA SUGGESTS OTHERWISE...THE HEAVY
LOOK OF SHEARING OCCURRING ALONG A MIDLEVEL CONVERGENCE BOUNDARY
THAT IS SUPPORTING THE SURFACE TROUGH AND CONTINUATION OF
REFLECTIVITY FINELINE. THE PROBLEM WITH THIS SURFACE TROUGH IS
THAT IT CONTINUES TO HOLD ON STRONGER THAN ANY OF THE MODEL
SOLUTIONS HAVE BEEN SUPPORTING. RH AND SPECIFIC HUMIDITY ANALYSES
SUGGESTS THAT CLEARING MAY BE DOWN TO THE M59 CORRIDOR BY SUNRISE
WITH CLOUDS SOLIDLY LOCKED IN OVER THE CENTRAL DETROIT METRO AREA
SOUTHWARD. THE CLEARING TREND MAY THEN ACCELERATE FOR THESE
SOUTHERN LOCATIONS AS WE HEAD INTO FRIDAY EVENING. FINALLY...COULD
BE LOOKING AT A PERIOD OF CLEAR SKIES FRIDAY NIGHT AND INTO THE
FIRST PART OF SATURDAY. LONGWAVE HEIGHT REBOUND AND WIND DIRECTION
CHANGE TO THE SOUTH BY LATE SATURDAY SUPPORTS THE RETURN OF
ORGANIZED MOISTURE ADVECTION AND CLOUDS.

ACTIVE WEATHER IS EXPECTED FOR THE REMAINDER OF THE FORECAST. THIS
WILL OCCUR AS A STRONG PACIFIC JET ENTERS THE PACIFIC
NORTHWEST...DEEPENS THE LONGWAVE TROUGH OVER THE CENTRAL CONUS...AND
EVENTUALLY CAUSES THE TROUGH TO BECOME NEGATIVELY TILTED AS THE JET
ENERGY ROUNDS THE BASE OF THE TROUGH TOWARD CHRISTMAS EVE. AT THE
SURFACE...A WEAKER LOW PRESSURE SYSTEM WILL EVOLVE OVER THE NORTHERN
PLAINS MONDAY/TUESDAY...EVENTUALLY GETTING ABSORBED BY A POTENTIALLY
STRONGER STORM LIFTING NORTHWARD FROM THE DEEP SOUTH. STILL LOTS OF
POSSIBLE SOLUTIONS AS TO HOW/WHERE THIS INTERACTION TAKES PLACE SO
THE DETAILS ARE FAR FROM BEING CLEAR. AT THIS POINT WILL HIGHLIGHT
THE POTENTIAL FOR IMPACTFUL WEATHER CENTERED AROUND
TUESDAY/WEDNESDAY. IMPACTS IN TERMS OF PRECIPITATION WILL BE MOST
LIKELY DURING THE MONDAY NIGHT THROUGH WEDNESDAY TIME FRAME.
MODEL CONSENSUS...WEAK AS IT IS AT THIS POINT...SUGGESTS WE HAVE A
BETTER CHANCE OF BEING ON THE WARMER SIDE OF THIS SYSTEM MONDAY
NIGHT THROUGH TUESDAY NIGHT...WITH COLDER AIR AND BREEZY CONDITIONS
BY CHRISTMAS EVE.

MARINE...

HIGH PRESSURE WILL BUILD INTO THE AREA TONIGHT...MAINTAINING
RELATIVELY RELAXED NORTHERLY WINDS FOR THE TIME OF YEAR. THE SURFACE
HIGH IS FORECASTED TO DRIFT ACROSS THE CENTRAL GREAT LAKES THIS
WEEKEND WITH SOUTHERLY FLOW EVENTUALLY RETURNING ON SUNDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

UPDATE.......MR
AVIATION.....MR
SHORT TERM...RK
LONG TERM....CB/DT
MARINE.......CB


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




AREA FORECAST DISCUSSION...UPDATED

NWS DULUTH MN

 1145 AM CST WED DEC 17 2014

.UPDATE...
ISSUED AT 1145 AM CST WED DEC 17 2014

GRAVITY WAVE AND SURFACE CONVERGENCE ZONE IS EXPECTED TO PERSIST
THROUGH THIS AFTERNOON. RADAR RETURNS HAD DIMINISHED SLIGHTLY
DURING THE MORNING...BUT EXPECT SNOW RATES TO INCREASE GRADUALLY
THROUGH THE AFTERNOON WITH CONVERGENCE AND GRAVITY WAVE STILL IN
PLACE. WILL EXTEND WINTER WEATHER ADVISORY FOR BAYFIELD COUNTY
THROUGH 6 PM. ADDITIONAL SNOWFALL THIS AFTERNOON FROM NORTHEAST
DOUGLAS ALONG THE HIGH TERRAIN IN BAYFIELD COUNTY OF UP TO 1.5
INCHES IS EXPECTED...WITH LESS THAN ONE TENTH FARTHER INLAND AND
IN THE LOWER TERRAIN. SNOWS OVER NORTHERN IRON AND NORTHEAST
ASHLAND COUNTY WILL CONTINUE THIS AFTERNOON...AND THE FOCUS SHOULD
SHIFT SLIGHTLY FARTHER WEST ALONG THE HIGH TERRAIN FROM ODANAH
EAST TO HURLEY. ADDITIONAL SNOWFALL OF UP TO 1 IS POSSIBLE IN
THOSE AREAS...WITH LESS THAN ONE TENTH FARTHER INLAND.

UPDATE ISSUED AT 1128 AM CST WED DEC 17 2014

UPDATED FOR THE NEW 18Z AVIATION DISCUSSION BELOW.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 317 AM CST WED DEC 17 2014

PRIMARY CONCERN FOR THE SHORT TERM PERIOD WAS LAKE EFFECT SNOWFALL
EVENT THIS MORNING AND INTO TODAY ACROSS THE SOUTH SHORE OF LAKE
SUPERIOR. OTHERWISE SEASONABLE CONDITIONS TODAY AND TOMORROW AS AN
AREA OF HIGH PRESSURE SETTLES IN ACROSS THE NORTHLAND.

EARLY THIS MORNING...OVERNIGHT RADAR RETURNS AND SURFACE
OBSERVATIONS INDICATED WIDESPREAD LIGHT SNOWFALL CONTINUED ACROSS
NORTHERN MINNESOTA. AS NEAR-SURFACE WINDS BACKED TO THE WEST LAKE
EFFECT SNOWFALL ACROSS THE SOUTH SHORE HAD TAPERED OFF...BUT AM
EXPECTING SNOW SHOWERS TO REDEVELOP TOWARDS SUNRISE THIS MORNING.
TEMPERATURES WERE HOLDING STEADY IN THE LOW TEENS ACROSS NORTHERN
MINNESOTA AND IN THE UPPER TEENS TO NEAR 20 IN NORTHWEST WISCONSIN.
WINDS WERE LIGHT OUT OF THE NORTHWEST AT 5 TO 10 KTS.

TODAY...THE WIDESPREAD LIGHT SNOW EARLY THIS MORNING WILL GRADUALLY
TAPER OFF AS WIDESPREAD SUBSIDENCE SETS IN DUE TO HIGH PRESSURE
MOVING INTO THE REGION. SKIES WILL BEGIN TO CLEAR PARTIALLY ALONG
THE INTERNATIONAL BORDER...BUT MOST LOCATIONS WILL REMAIN OVERCAST
DURING DAYLIGHT HOURS. A FEW FLURRIES WILL BE POSSIBLE IN THE LATE
AFTERNOON...BUT ACCUMULATING SNOWFALL WILL END BY MID-MORNING IN
MOST LOCATIONS. THE EXCEPTION WILL BE ALONG THE SOUTH SHORE OF LAKE
SUPERIOR WHERE LAKE EFFECT SNOW SHOWERS WILL REDEVELOP THIS
AFTERNOON AS THE LOW LEVEL WINDS BETTER ALIGN OUT OF THE NORTH. HAVE
DECREASED SNOWFALL AMOUNTS FROM PREVIOUS FORECASTS BASED ON THE
GUIDANCE AND EARLY MORNING OBSERVATIONS WHICH INDICATED LAKE EFFECT
SNOW SHOWERS HAVE TEMPORARILY DISSIPATED DUE TO BACKING OF
NEAR-SURFACE WINDS. RAP SOUNDINGS FOR THE SOUTH SHORE INDICATE THE
BEST LIFT TO BE BELOW THE DENDRITIC GROWTH ZONE...SO WHILE THERE
WILL BE FORCING AND MOISTURE...THE ALIGNMENT OF THE BEST LIFT MAY
RESULT IN LIMITED CRYSTAL GROWTH/AGGREGATION EXCEPT FOR ALONG THE
HIGHER TERRAIN WHERE MORE INTENSE SNOWFALL RATES COULD OCCUR.

DESPITE THESE RESERVATIONS FOR THE LAKE EFFECT SNOWFALL HAVE DECIDED
TO LEAVE THE CURRENT ADVISORY AND WARNING IN PLACE UNTIL WE BEGIN TO
RECEIVE SNOWFALL REPORTS THIS MORNING TO CONFIRM RADAR AND AUTOMATED
SURFACE OBSERVATIONS...BUT AM LEANING TOWARDS AN EARLY CANCELLATION
FOR THE WARNING AS ADDITIONAL AMOUNTS TODAY WILL PROBABLY ONLY BE IN
THE 1 TO 3 INCH RANGE.

HIGHS TODAY IN THE UPPER TEENS TO NEAR 20. WINDS WILL GRADUALLY VEER
TO THE NORTH/NORTHEAST AND WEAKEN TO 5 KTS OR LESS BY THE LATE
AFTERNOON.

TONIGHT...SOME CLEARING ALONG THE ARROWHEAD REGION OVERNIGHT WITH
NEAR CALM WINDS. A FEW LINGERING LIGHT SNOW SHOWERS/FLURRIES ALONG
THE SOUTH SHORE OF LAKE SUPERIOR. LOWS NEAR ZERO ALONG THE
INTERNATIONAL BORDER AND OTHER LOCATIONS WHERE SKIES MIGHT
CLEAR...ELSEWHERE IN THE LOW TEENS.

THURSDAY...INCREASING CLOUDS AS A MID-LEVEL DISTURBANCE MOVES EAST
ACROSS THE NORTHERN PLAINS AND INTO THE UPPER MIDWEST. THE 00Z HIRES
ARW DEPICTS AN AREA OF CONVERGENCE AND SNOW SHOWER DEVELOPING OVER
LAKE SUPERIOR BETWEEN TWO HARBORS AND HERBSTER...GRADUALLY DRIFTING
WEST TO BRING A FEW FLAKES TO THE NORTH SHORE BETWEEN THE TWIN PORTS
AND TWO HARBORS. DECIDED TO THROW IN A MENTION OF FLURRIES IN THIS
REGION AS WINDS APPEAR TO BE FAVORABLE FOR SUCH A DEVELOPMENT. VERY
LOW CONFIDENCE IN PREDICATION OF A MESOSCALE FEATURE LIKE THIS SO
FAR IN ADVANCE...BUT INTERESTING TO SEE THE HIGHER RESOLUTION ARW
MODEL PICK UP ON IT. HIGHS IN THE LOW TO MID 20S.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 317 AM CST WED DEC 17 2014

FAIRLY QUIET WEATHER PATTERN FOR THE LATTER HALF OF THE WEEK WITH AN
EXITING RIDGE OF HIGH PRESSURE TO THE EAST AND A MILD AND DRY UPPER
TROUGH DROPPING IN FROM THE NW TO PRODUCE LOW CHANCES FOR VERY LIGHT
SNOW SHOWERS LATE FRIDAY INTO SATURDAY. THE SYNOPTIC FLOW WILL
REMAIN CYCLONIC...BUT RELATIVELY DRY THROUGH THE REST OF THE WEEKEND
PRIOR TO A RE-ENFORCING WAVE EJECTING OUT OF THE NRN ROCKIES WITH AN
ASSOCIATED SFC LOW FORMING OVER THE CENTRAL PLAINS SUN NIGHT AND
TRACKING TO THE EAST INTO THE SRN GREAT LAKES BY MON NIGHT/ TUE
MORNING. THIS SYSTEM WILL PRODUCE WIDESPREAD SNOW SHOWERS ACROSS THE
NORTHLAND LATE SUNDAY INTO EARLY NEXT WEEK...AND ALSO USHER IN A
MUCH COOLER AIR MASS GOING INTO THE MIDDLE OF THE WEEK. SNOW AMOUNTS
APPEAR TO BE RELATIVELY LIGHT AT THIS TIME.

TEMPERATURES EARLY IN THE EXTENDED PERIOD WILL BE ON THE COOL SIDE
WITH HIGHS IN THE 20S AND LOWS IN THE TEENS AND SINGLE DIGITS ABOVE
ZERO ON FRIDAY. A SLIGHT WARM UP WILL BE FELT SAT THROUGH MONDAY
WITH HIGHS IN THE 30S AND LOWS IN THE 20S. THE NEXT DROP IN
TEMPERATURES WILL BEGIN TUESDAY WITH HIGHS BACK DOWN INTO THE 20S
AND OVERNIGHT LOWS IN THE TEENS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1128 AM CST WED DEC 17 2014

THERE HAS BEEN SOME CLEARING OVER NE MINNESOTA FROM THE NORTH THIS
MORNING AS HIGH PRESSURE IN MANITOBA AND NW ONTARIO GRADUALLY
APPROACHES THE MINNESOTA. WHILE MOSTLY CLEAR SKIES HAVE RETURNED
TO KINL/KHIB/KDLH...BKN/OVC MVFR CIGS AND IFR/MVFR VSBYS FROM -SN
FARTHER SOUTH...INCLUDING OVER KBRD AND NW WISCONSIN. THE LATEST
FORECASTS REFLECT A GREATER CONFIDENCE IN CLEARING THIS AFTERNOON
AND THIS EVENING. THE MVFR CONDITIONS WILL LIKELY LINGER AT KBRD
FOR AT LEAST EARLY THIS AFTERNOON...AND KHYR WILL NOT LIKELY
RETURN TO VFR UNTIL SOMETIME LATE THURSDAY MORNING DUE TO GREATER
MOISTURE FLOW FROM LAKE SUPERIOR. CLEAR AND CALM WEATHER IS
EXPECTED FOR MUCH OF NE MINNESOTA TONIGHT AS THE HIGH PRESSURE
MOVES THROUGH THE REGION. FOG COULD DEVELOP LATE TONIGHT AND EARLY
THURSDAY MORNING. HINTED AT THIS BY GIVING A PERIOD OF MVFR VSBYS
AT KINL/KHIB/KDLH/KBRD. MUCH OF THE REGION WOULD LIKELY RETURN TO
CLEAR SKIES AND VFR CONDITIONS BY LATE THURSDAY MORNING.


&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  21  14  24  16 /  30  10  10   0
INL  17   0  20  11 /  10   0   0   0
BRD  17  12  22  14 /  10   0   0   0
HYR  21  13  25  12 /  50  10  10   0
ASX  22  15  25  12 /  60  20  10   0

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR WIZ003-004.

     WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ002.

LS...NONE.
&&

$$

UPDATE...HUYCK
SHORT TERM...JJM
LONG TERM...BJT
AVIATION...GROCHOCINSKI









AREA FORECAST DISCUSSION...UPDATED

NWS DULUTH MN

 1128 AM CST WED DEC 17 2014

.UPDATE...
ISSUED AT 1128 AM CST WED DEC 17 2014

UPDATED FOR THE NEW 18Z AVIATION DISCUSSION BELOW.



UPDATE ISSUED AT 524 AM CST WED DEC 17 2014

UPDATED FOR AVIATION DISCUSSION BELOW.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 317 AM CST WED DEC 17 2014

PRIMARY CONCERN FOR THE SHORT TERM PERIOD WAS LAKE EFFECT SNOWFALL
EVENT THIS MORNING AND INTO TODAY ACROSS THE SOUTH SHORE OF LAKE
SUPERIOR. OTHERWISE SEASONABLE CONDITIONS TODAY AND TOMORROW AS AN
AREA OF HIGH PRESSURE SETTLES IN ACROSS THE NORTHLAND.

EARLY THIS MORNING...OVERNIGHT RADAR RETURNS AND SURFACE
OBSERVATIONS INDICATED WIDESPREAD LIGHT SNOWFALL CONTINUED ACROSS
NORTHERN MINNESOTA. AS NEAR-SURFACE WINDS BACKED TO THE WEST LAKE
EFFECT SNOWFALL ACROSS THE SOUTH SHORE HAD TAPERED OFF...BUT AM
EXPECTING SNOW SHOWERS TO REDEVELOP TOWARDS SUNRISE THIS MORNING.
TEMPERATURES WERE HOLDING STEADY IN THE LOW TEENS ACROSS NORTHERN
MINNESOTA AND IN THE UPPER TEENS TO NEAR 20 IN NORTHWEST WISCONSIN.
WINDS WERE LIGHT OUT OF THE NORTHWEST AT 5 TO 10 KTS.

TODAY...THE WIDESPREAD LIGHT SNOW EARLY THIS MORNING WILL GRADUALLY
TAPER OFF AS WIDESPREAD SUBSIDENCE SETS IN DUE TO HIGH PRESSURE
MOVING INTO THE REGION. SKIES WILL BEGIN TO CLEAR PARTIALLY ALONG
THE INTERNATIONAL BORDER...BUT MOST LOCATIONS WILL REMAIN OVERCAST
DURING DAYLIGHT HOURS. A FEW FLURRIES WILL BE POSSIBLE IN THE LATE
AFTERNOON...BUT ACCUMULATING SNOWFALL WILL END BY MID-MORNING IN
MOST LOCATIONS. THE EXCEPTION WILL BE ALONG THE SOUTH SHORE OF LAKE
SUPERIOR WHERE LAKE EFFECT SNOW SHOWERS WILL REDEVELOP THIS
AFTERNOON AS THE LOW LEVEL WINDS BETTER ALIGN OUT OF THE NORTH. HAVE
DECREASED SNOWFALL AMOUNTS FROM PREVIOUS FORECASTS BASED ON THE
GUIDANCE AND EARLY MORNING OBSERVATIONS WHICH INDICATED LAKE EFFECT
SNOW SHOWERS HAVE TEMPORARILY DISSIPATED DUE TO BACKING OF
NEAR-SURFACE WINDS. RAP SOUNDINGS FOR THE SOUTH SHORE INDICATE THE
BEST LIFT TO BE BELOW THE DENDRITIC GROWTH ZONE...SO WHILE THERE
WILL BE FORCING AND MOISTURE...THE ALIGNMENT OF THE BEST LIFT MAY
RESULT IN LIMITED CRYSTAL GROWTH/AGGREGATION EXCEPT FOR ALONG THE
HIGHER TERRAIN WHERE MORE INTENSE SNOWFALL RATES COULD OCCUR.

DESPITE THESE RESERVATIONS FOR THE LAKE EFFECT SNOWFALL HAVE DECIDED
TO LEAVE THE CURRENT ADVISORY AND WARNING IN PLACE UNTIL WE BEGIN TO
RECEIVE SNOWFALL REPORTS THIS MORNING TO CONFIRM RADAR AND AUTOMATED
SURFACE OBSERVATIONS...BUT AM LEANING TOWARDS AN EARLY CANCELLATION
FOR THE WARNING AS ADDITIONAL AMOUNTS TODAY WILL PROBABLY ONLY BE IN
THE 1 TO 3 INCH RANGE.

HIGHS TODAY IN THE UPPER TEENS TO NEAR 20. WINDS WILL GRADUALLY VEER
TO THE NORTH/NORTHEAST AND WEAKEN TO 5 KTS OR LESS BY THE LATE
AFTERNOON.

TONIGHT...SOME CLEARING ALONG THE ARROWHEAD REGION OVERNIGHT WITH
NEAR CALM WINDS. A FEW LINGERING LIGHT SNOW SHOWERS/FLURRIES ALONG
THE SOUTH SHORE OF LAKE SUPERIOR. LOWS NEAR ZERO ALONG THE
INTERNATIONAL BORDER AND OTHER LOCATIONS WHERE SKIES MIGHT
CLEAR...ELSEWHERE IN THE LOW TEENS.

THURSDAY...INCREASING CLOUDS AS A MID-LEVEL DISTURBANCE MOVES EAST
ACROSS THE NORTHERN PLAINS AND INTO THE UPPER MIDWEST. THE 00Z HIRES
ARW DEPICTS AN AREA OF CONVERGENCE AND SNOW SHOWER DEVELOPING OVER
LAKE SUPERIOR BETWEEN TWO HARBORS AND HERBSTER...GRADUALLY DRIFTING
WEST TO BRING A FEW FLAKES TO THE NORTH SHORE BETWEEN THE TWIN PORTS
AND TWO HARBORS. DECIDED TO THROW IN A MENTION OF FLURRIES IN THIS
REGION AS WINDS APPEAR TO BE FAVORABLE FOR SUCH A DEVELOPMENT. VERY
LOW CONFIDENCE IN PREDICATION OF A MESOSCALE FEATURE LIKE THIS SO
FAR IN ADVANCE...BUT INTERESTING TO SEE THE HIGHER RESOLUTION ARW
MODEL PICK UP ON IT. HIGHS IN THE LOW TO MID 20S.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 317 AM CST WED DEC 17 2014

FAIRLY QUIET WEATHER PATTERN FOR THE LATTER HALF OF THE WEEK WITH AN
EXITING RIDGE OF HIGH PRESSURE TO THE EAST AND A MILD AND DRY UPPER
TROUGH DROPPING IN FROM THE NW TO PRODUCE LOW CHANCES FOR VERY LIGHT
SNOW SHOWERS LATE FRIDAY INTO SATURDAY. THE SYNOPTIC FLOW WILL
REMAIN CYCLONIC...BUT RELATIVELY DRY THROUGH THE REST OF THE WEEKEND
PRIOR TO A RE-ENFORCING WAVE EJECTING OUT OF THE NRN ROCKIES WITH AN
ASSOCIATED SFC LOW FORMING OVER THE CENTRAL PLAINS SUN NIGHT AND
TRACKING TO THE EAST INTO THE SRN GREAT LAKES BY MON NIGHT/ TUE
MORNING. THIS SYSTEM WILL PRODUCE WIDESPREAD SNOW SHOWERS ACROSS THE
NORTHLAND LATE SUNDAY INTO EARLY NEXT WEEK...AND ALSO USHER IN A
MUCH COOLER AIR MASS GOING INTO THE MIDDLE OF THE WEEK. SNOW AMOUNTS
APPEAR TO BE RELATIVELY LIGHT AT THIS TIME.

TEMPERATURES EARLY IN THE EXTENDED PERIOD WILL BE ON THE COOL SIDE
WITH HIGHS IN THE 20S AND LOWS IN THE TEENS AND SINGLE DIGITS ABOVE
ZERO ON FRIDAY. A SLIGHT WARM UP WILL BE FELT SAT THROUGH MONDAY
WITH HIGHS IN THE 30S AND LOWS IN THE 20S. THE NEXT DROP IN
TEMPERATURES WILL BEGIN TUESDAY WITH HIGHS BACK DOWN INTO THE 20S
AND OVERNIGHT LOWS IN THE TEENS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1128 AM CST WED DEC 17 2014

THERE HAS BEEN SOME CLEARING OVER NE MINNESOTA FROM THE NORTH THIS
MORNING AS HIGH PRESSURE IN MANITOBA AND NW ONTARIO GRADUALLY
APPROACHES THE MINNESOTA. WHILE MOSTLY CLEAR SKIES HAVE RETURNED
TO KINL/KHIB/KDLH...BKN/OVC MVFR CIGS AND IFR/MVFR VSBYS FROM -SN
FARTHER SOUTH...INCLUDING OVER KBRD AND NW WISCONSIN. THE LATEST
FORECASTS REFLECT A GREATER CONFIDENCE IN CLEARING THIS AFTERNOON
AND THIS EVENING. THE MVFR CONDITIONS WILL LIKELY LINGER AT KBRD
FOR AT LEAST EARLY THIS AFTERNOON...AND KHYR WILL NOT LIKELY
RETURN TO VFR UNTIL SOMETIME LATE THURSDAY MORNING DUE TO GREATER
MOISTURE FLOW FROM LAKE SUPERIOR. CLEAR AND CALM WEATHER IS
EXPECTED FOR MUCH OF NE MINNESOTA TONIGHT AS THE HIGH PRESSURE
MOVES THROUGH THE REGION. FOG COULD DEVELOP LATE TONIGHT AND EARLY
THURSDAY MORNING. HINTED AT THIS BY GIVING A PERIOD OF MVFR VSBYS
AT KINL/KHIB/KDLH/KBRD. MUCH OF THE REGION WOULD LIKELY RETURN TO
CLEAR SKIES AND VFR CONDITIONS BY LATE THURSDAY MORNING.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  21  14  24  16 /  30  10  10   0
INL  17   0  20  11 /  10   0   0   0
BRD  17  12  22  14 /  10   0   0   0
HYR  21  13  25  12 /  50  10  10   0
ASX  22  15  25  12 /  60  20  10   0

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR WIZ003-004.

     WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ002.

LS...NONE.
&&

$$

SHORT TERM...JJM
LONG TERM...BJT
AVIATION...GROCHOCINSKI






AREA FORECAST DISCUSSION...UPDATED

NWS DULUTH MN

 528 AM CST WED DEC 17 2014

.UPDATE...
ISSUED AT 524 AM CST WED DEC 17 2014

UPDATED FOR AVIATION DISCUSSION BELOW.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 317 AM CST WED DEC 17 2014

PRIMARY CONCERN FOR THE SHORT TERM PERIOD WAS LAKE EFFECT SNOWFALL
EVENT THIS MORNING AND INTO TODAY ACROSS THE SOUTH SHORE OF LAKE
SUPERIOR. OTHERWISE SEASONABLE CONDITIONS TODAY AND TOMORROW AS AN
AREA OF HIGH PRESSURE SETTLES IN ACROSS THE NORTHLAND.

EARLY THIS MORNING...OVERNIGHT RADAR RETURNS AND SURFACE
OBSERVATIONS INDICATED WIDESPREAD LIGHT SNOWFALL CONTINUED ACROSS
NORTHERN MINNESOTA. AS NEAR-SURFACE WINDS BACKED TO THE WEST LAKE
EFFECT SNOWFALL ACROSS THE SOUTH SHORE HAD TAPERED OFF...BUT AM
EXPECTING SNOW SHOWERS TO REDEVELOP TOWARDS SUNRISE THIS MORNING.
TEMPERATURES WERE HOLDING STEADY IN THE LOW TEENS ACROSS NORTHERN
MINNESOTA AND IN THE UPPER TEENS TO NEAR 20 IN NORTHWEST WISCONSIN.
WINDS WERE LIGHT OUT OF THE NORTHWEST AT 5 TO 10 KTS.

TODAY...THE WIDESPREAD LIGHT SNOW EARLY THIS MORNING WILL GRADUALLY
TAPER OFF AS WIDESPREAD SUBSIDENCE SETS IN DUE TO HIGH PRESSURE
MOVING INTO THE REGION. SKIES WILL BEGIN TO CLEAR PARTIALLY ALONG
THE INTERNATIONAL BORDER...BUT MOST LOCATIONS WILL REMAIN OVERCAST
DURING DAYLIGHT HOURS. A FEW FLURRIES WILL BE POSSIBLE IN THE LATE
AFTERNOON...BUT ACCUMULATING SNOWFALL WILL END BY MID-MORNING IN
MOST LOCATIONS. THE EXCEPTION WILL BE ALONG THE SOUTH SHORE OF LAKE
SUPERIOR WHERE LAKE EFFECT SNOW SHOWERS WILL REDEVELOP THIS
AFTERNOON AS THE LOW LEVEL WINDS BETTER ALIGN OUT OF THE NORTH. HAVE
DECREASED SNOWFALL AMOUNTS FROM PREVIOUS FORECASTS BASED ON THE
GUIDANCE AND EARLY MORNING OBSERVATIONS WHICH INDICATED LAKE EFFECT
SNOW SHOWERS HAVE TEMPORARILY DISSIPATED DUE TO BACKING OF
NEAR-SURFACE WINDS. RAP SOUNDINGS FOR THE SOUTH SHORE INDICATE THE
BEST LIFT TO BE BELOW THE DENDRITIC GROWTH ZONE...SO WHILE THERE
WILL BE FORCING AND MOISTURE...THE ALIGNMENT OF THE BEST LIFT MAY
RESULT IN LIMITED CRYSTAL GROWTH/AGGREGATION EXCEPT FOR ALONG THE
HIGHER TERRAIN WHERE MORE INTENSE SNOWFALL RATES COULD OCCUR.

DESPITE THESE RESERVATIONS FOR THE LAKE EFFECT SNOWFALL HAVE DECIDED
TO LEAVE THE CURRENT ADVISORY AND WARNING IN PLACE UNTIL WE BEGIN TO
RECEIVE SNOWFALL REPORTS THIS MORNING TO CONFIRM RADAR AND AUTOMATED
SURFACE OBSERVATIONS...BUT AM LEANING TOWARDS AN EARLY CANCELLATION
FOR THE WARNING AS ADDITIONAL AMOUNTS TODAY WILL PROBABLY ONLY BE IN
THE 1 TO 3 INCH RANGE.

HIGHS TODAY IN THE UPPER TEENS TO NEAR 20. WINDS WILL GRADUALLY VEER
TO THE NORTH/NORTHEAST AND WEAKEN TO 5 KTS OR LESS BY THE LATE
AFTERNOON.

TONIGHT...SOME CLEARING ALONG THE ARROWHEAD REGION OVERNIGHT WITH
NEAR CALM WINDS. A FEW LINGERING LIGHT SNOW SHOWERS/FLURRIES ALONG
THE SOUTH SHORE OF LAKE SUPERIOR. LOWS NEAR ZERO ALONG THE
INTERNATIONAL BORDER AND OTHER LOCATIONS WHERE SKIES MIGHT
CLEAR...ELSEWHERE IN THE LOW TEENS.

THURSDAY...INCREASING CLOUDS AS A MID-LEVEL DISTURBANCE MOVES EAST
ACROSS THE NORTHERN PLAINS AND INTO THE UPPER MIDWEST. THE 00Z HIRES
ARW DEPICTS AN AREA OF CONVERGENCE AND SNOW SHOWER DEVELOPING OVER
LAKE SUPERIOR BETWEEN TWO HARBORS AND HERBSTER...GRADUALLY DRIFTING
WEST TO BRING A FEW FLAKES TO THE NORTH SHORE BETWEEN THE TWIN PORTS
AND TWO HARBORS. DECIDED TO THROW IN A MENTION OF FLURRIES IN THIS
REGION AS WINDS APPEAR TO BE FAVORABLE FOR SUCH A DEVELOPMENT. VERY
LOW CONFIDENCE IN PREDICATION OF A MESOSCALE FEATURE LIKE THIS SO
FAR IN ADVANCE...BUT INTERESTING TO SEE THE HIGHER RESOLUTION ARW
MODEL PICK UP ON IT. HIGHS IN THE LOW TO MID 20S.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 317 AM CST WED DEC 17 2014

FAIRLY QUIET WEATHER PATTERN FOR THE LATTER HALF OF THE WEEK WITH AN
EXITING RIDGE OF HIGH PRESSURE TO THE EAST AND A MILD AND DRY UPPER
TROUGH DROPPING IN FROM THE NW TO PRODUCE LOW CHANCES FOR VERY LIGHT
SNOW SHOWERS LATE FRIDAY INTO SATURDAY. THE SYNOPTIC FLOW WILL
REMAIN CYCLONIC...BUT RELATIVELY DRY THROUGH THE REST OF THE WEEKEND
PRIOR TO A RE-ENFORCING WAVE EJECTING OUT OF THE NRN ROCKIES WITH AN
ASSOCIATED SFC LOW FORMING OVER THE CENTRAL PLAINS SUN NIGHT AND
TRACKING TO THE EAST INTO THE SRN GREAT LAKES BY MON NIGHT/ TUE
MORNING. THIS SYSTEM WILL PRODUCE WIDESPREAD SNOW SHOWERS ACROSS THE
NORTHLAND LATE SUNDAY INTO EARLY NEXT WEEK...AND ALSO USHER IN A
MUCH COOLER AIR MASS GOING INTO THE MIDDLE OF THE WEEK. SNOW AMOUNTS
APPEAR TO BE RELATIVELY LIGHT AT THIS TIME.

TEMPERATURES EARLY IN THE EXTENDED PERIOD WILL BE ON THE COOL SIDE
WITH HIGHS IN THE 20S AND LOWS IN THE TEENS AND SINGLE DIGITS ABOVE
ZERO ON FRIDAY. A SLIGHT WARM UP WILL BE FELT SAT THROUGH MONDAY
WITH HIGHS IN THE 30S AND LOWS IN THE 20S. THE NEXT DROP IN
TEMPERATURES WILL BEGIN TUESDAY WITH HIGHS BACK DOWN INTO THE 20S
AND OVERNIGHT LOWS IN THE TEENS.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 524 AM CST WED DEC 17 2014

MVFR CEILINGS WILL PERSIST THROUGH THE MORNING AND INTO THE
AFTERNOON WITH ONLY BRIEF BREAKS TO VFR AT TIMES. MVFR
VISIBILITIES IN SCATTERED SNOW SHOWERS ARE POSSIBLE WITH ON AND
OFF FLURRIES. WILL BEGIN TO LOSE THE MOISTURE ALOFT...BUT KEEP A
SOLID LOW LAYER OF MOISTURE/LOW CLOUDS AROUND THROUGH TONIGHT. THE
EXCEPTION WILL BE AROUND HIB AND INL...WHICH COULD CLEAR OUT...BUT
COULD SEE REDEVELOPMENT OF FOG LATE TONIGHT AND THUR MORNING.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  21  14  24  16 /  30  10  10   0
INL  17   0  20  11 /  10   0   0   0
BRD  17  12  22  14 /  10   0   0   0
HYR  21  13  25  12 /  20  10   0   0
ASX  22  15  25  12 /  60  20  10   0

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR WIZ003-004.

     WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ002.

LS...SMALL CRAFT ADVISORY UNTIL 10 AM CST THIS MORNING FOR LSZ121-
     145>148.

&&

$$

SHORT TERM...JJM
LONG TERM...BJT
AVIATION...BJT







AREA FORECAST DISCUSSION

NWS DULUTH MN

 317 AM CST WED DEC 17 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 317 AM CST WED DEC 17 2014

PRIMARY CONCERN FOR THE SHORT TERM PERIOD WAS LAKE EFFECT SNOWFALL
EVENT THIS MORNING AND INTO TODAY ACROSS THE SOUTH SHORE OF LAKE
SUPERIOR. OTHERWISE SEASONABLE CONDITIONS TODAY AND TOMORROW AS AN
AREA OF HIGH PRESSURE SETTLES IN ACROSS THE NORTHLAND.

EARLY THIS MORNING...OVERNIGHT RADAR RETURNS AND SURFACE
OBSERVATIONS INDICATED WIDESPREAD LIGHT SNOWFALL CONTINUED ACROSS
NORTHERN MINNESOTA. AS NEAR-SURFACE WINDS BACKED TO THE WEST LAKE
EFFECT SNOWFALL ACROSS THE SOUTH SHORE HAD TAPERED OFF...BUT AM
EXPECTING SNOW SHOWERS TO REDEVELOP TOWARDS SUNRISE THIS MORNING.
TEMPERATURES WERE HOLDING STEADY IN THE LOW TEENS ACROSS NORTHERN
MINNESOTA AND IN THE UPPER TEENS TO NEAR 20 IN NORTHWEST WISCONSIN.
WINDS WERE LIGHT OUT OF THE NORTHWEST AT 5 TO 10 KTS.

TODAY...THE WIDESPREAD LIGHT SNOW EARLY THIS MORNING WILL GRADUALLY
TAPER OFF AS WIDESPREAD SUBSIDENCE SETS IN DUE TO HIGH PRESSURE
MOVING INTO THE REGION. SKIES WILL BEGIN TO CLEAR PARTIALLY ALONG
THE INTERNATIONAL BORDER...BUT MOST LOCATIONS WILL REMAIN OVERCAST
DURING DAYLIGHT HOURS. A FEW FLURRIES WILL BE POSSIBLE IN THE LATE
AFTERNOON...BUT ACCUMULATING SNOWFALL WILL END BY MID-MORNING IN
MOST LOCATIONS. THE EXCEPTION WILL BE ALONG THE SOUTH SHORE OF LAKE
SUPERIOR WHERE LAKE EFFECT SNOW SHOWERS WILL REDEVELOP THIS
AFTERNOON AS THE LOW LEVEL WINDS BETTER ALIGN OUT OF THE NORTH. HAVE
DECREASED SNOWFALL AMOUNTS FROM PREVIOUS FORECASTS BASED ON THE
GUIDANCE AND EARLY MORNING OBSERVATIONS WHICH INDICATED LAKE EFFECT
SNOW SHOWERS HAVE TEMPORARILY DISSIPATED DUE TO BACKING OF
NEAR-SURFACE WINDS. RAP SOUNDINGS FOR THE SOUTH SHORE INDICATE THE
BEST LIFT TO BE BELOW THE DENDRITIC GROWTH ZONE...SO WHILE THERE
WILL BE FORCING AND MOISTURE...THE ALIGNMENT OF THE BEST LIFT MAY
RESULT IN LIMITED CRYSTAL GROWTH/AGGREGATION EXCEPT FOR ALONG THE
HIGHER TERRAIN WHERE MORE INTENSE SNOWFALL RATES COULD OCCUR.

DESPITE THESE RESERVATIONS FOR THE LAKE EFFECT SNOWFALL HAVE DECIDED
TO LEAVE THE CURRENT ADVISORY AND WARNING IN PLACE UNTIL WE BEGIN TO
RECEIVE SNOWFALL REPORTS THIS MORNING TO CONFIRM RADAR AND AUTOMATED
SURFACE OBSERVATIONS...BUT AM LEANING TOWARDS AN EARLY CANCELLATION
FOR THE WARNING AS ADDITIONAL AMOUNTS TODAY WILL PROBABLY ONLY BE IN
THE 1 TO 3 INCH RANGE.

HIGHS TODAY IN THE UPPER TEENS TO NEAR 20. WINDS WILL GRADUALLY VEER
TO THE NORTH/NORTHEAST AND WEAKEN TO 5 KTS OR LESS BY THE LATE
AFTERNOON.

TONIGHT...SOME CLEARING ALONG THE ARROWHEAD REGION OVERNIGHT WITH
NEAR CALM WINDS. A FEW LINGERING LIGHT SNOW SHOWERS/FLURRIES ALONG
THE SOUTH SHORE OF LAKE SUPERIOR. LOWS NEAR ZERO ALONG THE
INTERNATIONAL BORDER AND OTHER LOCATIONS WHERE SKIES MIGHT
CLEAR...ELSEWHERE IN THE LOW TEENS.

THURSDAY...INCREASING CLOUDS AS A MID-LEVEL DISTURBANCE MOVES EAST
ACROSS THE NORTHERN PLAINS AND INTO THE UPPER MIDWEST. THE 00Z HIRES
ARW DEPICTS AN AREA OF CONVERGENCE AND SNOW SHOWER DEVELOPING OVER
LAKE SUPERIOR BETWEEN TWO HARBORS AND HERBSTER...GRADUALLY DRIFTING
WEST TO BRING A FEW FLAKES TO THE NORTH SHORE BETWEEN THE TWIN PORTS
AND TWO HARBORS. DECIDED TO THROW IN A MENTION OF FLURRIES IN THIS
REGION AS WINDS APPEAR TO BE FAVORABLE FOR SUCH A DEVELOPMENT. VERY
LOW CONFIDENCE IN PREDICATION OF A MESOSCALE FEATURE LIKE THIS SO
FAR IN ADVANCE...BUT INTERESTING TO SEE THE HIGHER RESOLUTION ARW
MODEL PICK UP ON IT. HIGHS IN THE LOW TO MID 20S.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 317 AM CST WED DEC 17 2014

FAIRLY QUIET WEATHER PATTERN FOR THE LATTER HALF OF THE WEEK WITH AN
EXITING RIDGE OF HIGH PRESSURE TO THE EAST AND A MILD AND DRY UPPER
TROUGH DROPPING IN FROM THE NW TO PRODUCE LOW CHANCES FOR VERY LIGHT
SNOW SHOWERS LATE FRIDAY INTO SATURDAY. THE SYNOPTIC FLOW WILL
REMAIN CYCLONIC...BUT RELATIVELY DRY THROUGH THE REST OF THE WEEKEND
PRIOR TO A RE-ENFORCING WAVE EJECTING OUT OF THE NRN ROCKIES WITH AN
ASSOCIATED SFC LOW FORMING OVER THE CENTRAL PLAINS SUN NIGHT AND
TRACKING TO THE EAST INTO THE SRN GREAT LAKES BY MON NIGHT/ TUE
MORNING. THIS SYSTEM WILL PRODUCE WIDESPREAD SNOW SHOWERS ACROSS THE
NORTHLAND LATE SUNDAY INTO EARLY NEXT WEEK...AND ALSO USHER IN A
MUCH COOLER AIR MASS GOING INTO THE MIDDLE OF THE WEEK. SNOW AMOUNTS
APPEAR TO BE RELATIVELY LIGHT AT THIS TIME.

TEMPERATURES EARLY IN THE EXTENDED PERIOD WILL BE ON THE COOL SIDE
WITH HIGHS IN THE 20S AND LOWS IN THE TEENS AND SINGLE DIGITS ABOVE
ZERO ON FRIDAY. A SLIGHT WARM UP WILL BE FELT SAT THROUGH MONDAY
WITH HIGHS IN THE 30S AND LOWS IN THE 20S. THE NEXT DROP IN
TEMPERATURES WILL BEGIN TUESDAY WITH HIGHS BACK DOWN INTO THE 20S
AND OVERNIGHT LOWS IN THE TEENS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1131 PM CST TUE DEC 16 2014

A MIX OF VFR/MVFR CIGS WITH AREAS OF LIGHT SNOW REDUCING VSBYS
INTO THE MVFR RANGE. THESE CONDITIONS WILL PERSIST THROUGH MUCH OF
THE FORECAST. AN IMPROVEMENT TO VFR WITH AN END TO THE SNOW AT INL
BY 10Z...HIB BY 18Z...DLH/BRD/HYR BY 00Z.


&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  21  14  24  16 /  30  10  10   0
INL  17   0  20  11 /  10   0   0   0
BRD  17  12  22  14 /  10   0   0   0
HYR  21  13  25  12 /  20  10   0   0
ASX  22  15  25  12 /  60  20  10   0

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR WIZ003-004.

     WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ002.

LS...SMALL CRAFT ADVISORY UNTIL 10 AM CST THIS MORNING FOR LSZ121-
     145>148.

&&

$$

SHORT TERM...JJM
LONG TERM...BJT
AVIATION...GSF






AREA FORECAST DISCUSSION

NWS BILLINGS MT

 231 PM MST WED DEC 17 2014

.SHORT TERM...VALID FOR THU AND FRI...

WEAK UPPER LOW PRESSURE SYSTEM WILL MOVE ACROSS NORTHERN MONTANA
TONIGHT AND WILL BRING AREAS OF LIGHT SNOW THIS EVENING ACROSS OUR
NORTHEAST ZONES. SNOW IS EXPECTED TO BE VERY LIGHT WITH NO
ACCUMULATIONS. AS THE LOW MOVES TO OUR EAST TONIGHT...SOME
CLEARING IS EXPECTED ACROSS OUR WESTERN AND CENTRAL ZONES. THIS
WILL ALLOW FOR COOLER OVERNIGHT LOW TEMPERATURES WITH TEENS TO
LOWER 20S. HRRR IS INDICATING FOG TO REDEVELOP OVER SOUTHERN
POWDER RIVER AND CARTER COUNTIES TONIGHT AS LOW LEVEL MOISTURE
REMAINS POOLED OVER THESE AREAS. DID INCLUDED PATCHY FOG FOR
PORTIONS OF SOUTHEAST MONTANA TONIGHT. WEAK SHORT WAVE TO MOVE
THROUGH THURSDAY WHICH WHICH WILL BRING SCATTERED SNOW SHOWERS TO
OUR SOUTHWEST MOUNTAINS. DRY WEATHER AND SLOWLY WARMING
TEMPERATURES WILL CONTINUE INTO FRIDAY AS SHORT WAVE RIDGING MOVES
IN OVER THE REGION. HIGH TEMPERATURES WILL BE IN THE UPPER 30S TO
LOWER 40S BOTH THURSDAY AND FRIDAY. RICHMOND

.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...

GUIDANCE CONTINUES TO BE IN GOOD AGREEMENT INTO EARLY NEXT WEEK.
WHILE THE FINER DETAILS MAY DIFFER..THE OVERALL UNSETTLED PATTERN
IN THE EXTENDED CONTINUES. AFTER THE RIDGING FRIDAY...A WEAK
SHORTWAVE WILL CROSS THE STATE...BRING ANOTHER CHANCE FOR LIGHT
PRECIP TO THE MOUNTAINS. UPPER LEVEL FLOW BEGINS TO INCREASE
SATURDAY NIGHT AS A PACIFIC JET STARTS MOVING INTO THE STATE. LEE
SIDE TROUGHING DEVELOPS...WITH A SURFACE LOW DEVELOPING OVER
SOUTHERN ALBERTA. IN RESPONSE...THE PRESSURE GRADIENT TIGHTENS
OVER SOUTHERN MONTANA...RESULTING IN STRONGER WINDS DEVELOPING
FIRST IN THE GAP AREAS...THEN SPREADING OUT TO AROUND BILLINGS.
MEX MOS FOR LIVINGSTON HAS WINDS INCREASING INTO 30 MPH TO NEAR
40 MPH RANGE SUNDAY AFTERNOON. STILL KEEPING GRIDS SUB ADVISORY
GIVEN THIS IS STILL FOUR DAYS OUT...BUT IF CURRENT TRENDS
HOLD...LOOKING AT ANOTHER WIND EVENT DURING THE DAY SUNDAY.

AS THE LOW TRACKS OUT OF CANADA INTO THE NORTHERN PLAINS
MONDAY...A COLD FRONT MOVES THROUGH THE AREA. WITH AMPLE MOISTURE
STILL BRING TRANSPORTED INTO THE AREA...POPS CONTINUE MONDAY INTO
TUESDAY. TEMPERATURES WILL REMAIN RELATIVELY WARM...SO MUCH OF THE
CENTRAL ZONES STILL LOOK TO GET RAIN. FARTHER EAST WARDS MILES
CITY AND BAKER...WHERE TEMPERATURES ARE A BIT COOLER...MAY SEE
SOME FREEZING RAIN. WINDS WILL ALSO BE MORE NORTH WESTERLY...SO
NOT AS MUCH OF AN UP SLOPE FLOW EVENT. THINGS BEGIN TO TAPPER
OFF...WITH TEMPERATURES COOLING BACK INTO THE 30S FOR HIGHS.

LOOKING AHEAD TO CHRISTMAS EVE AND CHRISTMAS...ANOTHER LOW
DEVELOPS AND TRACKS ACROSS MONTANA...GIVING THE AREA A SHOT AT
MORE PRECIP. WITH THE SYSTEM...THE AIR MASS IN PLACE WILL BE
COLDER...WITH 850MB TEMPERATURES BELOW FREEZING. THE THE GFS AND
ECMWF ARE SUGGESTING A SHOT AT A WHITE CHRISTMAS...WILL CONTINUE
TO WATCH THIS. REIMER &&

.AVIATION...

CONDITIONS HAVE IMPROVED THIS AFTERNOON...GENERALLY MVFR TO VFR.
EXPECT FLIGHT CONDITIONS REMAIN VFR/MVFR OVERNIGHT AND INTO
TOMORROW. SOME PATCH FOG WILL BE POSSIBLE SOUTH OF MILES
CITY...BUT WILL LIKELY NOT IMPACT ANY TERMINALS. WITH SOME MID LEVEL
CLOUDS...SOME MOUNTAIN OBSCURATION WILL CONTINUE TO BE POSSIBLE.
REIMER
&&

.PRELIMINARY POINT TEMP/POPS...

    THU     FRI     SAT     SUN     MON     TUE     WED
-----------------------------------------------------------
BIL 023/038 023/038 027/041 027/046 033/045 026/038 022/033
    00/B    00/B    11/B    13/W    32/W    21/N    23/J
LVM 022/042 024/040 027/043 028/046 035/045 022/039 023/035
    01/N    11/N    21/B    24/W    43/W    21/N    33/J
HDN 013/037 015/037 020/040 021/044 029/043 021/037 020/034
    10/B    00/B    01/B    13/W    33/W    21/B    22/J
MLS 017/038 019/037 021/040 022/042 029/040 025/036 020/031
    20/B    00/B    11/B    13/W    22/W    11/B    11/E
4BQ 015/041 017/040 019/041 022/044 030/042 024/037 019/033
    20/B    00/B    11/B    12/W    23/W    21/B    22/J
BHK 015/036 019/037 019/040 021/042 026/037 021/033 017/027
    20/B    10/B    01/B    02/W    22/W    11/N    11/B
SHR 015/041 015/038 020/040 019/043 030/042 022/037 019/033
    10/B    10/B    11/B    13/W    34/W    32/J    22/J

&&

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.

&&

$$
WEATHER.GOV/BILLINGS



AREA FORECAST DISCUSSION

NWS BILLINGS MT

 921 AM MST WED DEC 17 2014

.UPDATE...
AREAS OF FOG STILL ON GOING ACROSS THE REGION THIS MORNING AND
WILL CONTINUE THROUGH AT LEAST 19Z FOR MANY AREAS FROM BILLINGS
EAST. DENSE FOG WAS CONTINUING IN THE SHERIDAN AND WILL KEEP THE
DENSE FOG ADVISORY GOING THROUGH AT LEAST 18Z. WEB CAMS AND
SURFACE OBSERVATIONS ALSO INDICATED PATCHY DENSE FOG WAS LOCATED
ACROSS THE SOUTHERN AREAS OF POWDER RIVER AND CARTER COUNTIES.
PATCHY FOG ALSO EXTENDED NORTHWARD FROM THESE AREAS AND HAD PUSHED
WESTWARD INTO THE BILLINGS AREA. HRRR INDICATING FOG IN THESE
AREAS WILL BEGIN BREAKING UP BY MID MORNING AS A WARM FRONT MOVES
ACROSS THE AREA ALLOWING SOME MIXING TO TAKE PLACE.

INCREASE POPS ACROSS THE AREA THIS MORNING AS A WEAK UPPER LEVEL
CIRCULATION ALONG WITH WEAK VORTICITY WAS PRODUCING LIGHT SNOW
SHOWERS OVER THE FORECAST AREA. NO SNOW ACCUMULATIONS ARE EXPECTED
WITH THIS DISTURBANCE. DID LOWER TEMPERATURES A FEW DEGREES AS
CLOUD COVER WILL INHIBIT HEATING THIS AFTERNOON IN SPITE OF WARM
FRONT MOVING THROUGH. RICHMOND

&&

.SHORT TERM...VALID FOR TDY AND THU...

SHERIDAN WAS REPORTING DENSE FOG THIS MORNING AND AREA WEB CAMS
IN SHERIDAN ALSO SHOWED DENSE FOG. LAST FEW RUNS OF THE HRRR
TARGETED THE SHERIDAN FOOTHILLS WITH DENSE FOG AND DISSIPATED IT
BY 19Z. HAVE ISSUED A DENSE FOG ADVISORY FOR THIS AREA THROUGH
18Z. OTHER AREAS E OF KBIL WILL ALSO HAVE FOG...AND SOME OF IT MAY
BE DENSE...BUT DENSE FOG WILL NOT BE WIDESPREAD ENOUGH TO WARRANT
AN ADVISORY.

TWO SHORTWAVES WERE AFFECTING THE AREA EARLY THIS MORNING. ONE WAS
MOVING INTO SW MT AND THE OTHER WAS OVER W MT PER WATER VAPOR
IMAGERY. THESE WAVES WILL MERGE AND CROSS THE AREA TODAY THROUGH
TONIGHT. THE BEST Q-VECTOR CONVERGENCE WILL OCCUR THIS MORNING
WITH THE WAVES...AND MODELS BROUGHT A DECENT AREA OF MOISTURE
ACROSS THE AREA. DETERMINISTIC MODELS AND SREF ALL SHOWED LIGHT
WIDELY SCATTERED QPF TODAY. SO WENT WITH MAINLY SCATTERED
FLURRIES...WITH CHANCE POPS IN THE WESTERN MOUNTAINS THIS MORNING.
CHANCES FOR PRECIPITATION WILL END TONIGHT. A WARM FRONT WILL PUSH
INTO THE REGION TONIGHT AND USHER IN WARMING CONDITIONS THROUGH
THU. ANOTHER WAVE APPROACHES THU AND MOVES INTO THE AREA THU
NIGHT. PRECIPITATION CHANCES WILL BE CONFINED TO THE MOUNTAINS.

TEMPERATURES TODAY WILL BE HIGHER THAN YESTERDAY/S READINGS AND
WILL BE WARMER YET ON THU. ARTHUR

.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...

MODELS ARE IN DECENT AGREEMENT THROUGH THE EXTENDED PERIOD AS
THEY SHOW AN UNSETTLED PATTERN. MAIN FORECAST ISSUE WILL BE SUNDAY
INTO MONDAY AND AGAIN CHRISTMAS EVE/CHRISTMAS DAY AS THESE
PERIODS SHOW THE LIKELIHOOD OF A STORM SYSTEM IMPACTING THE AREA.
BRIEF RIDGING WILL BE OVER THE FORECAST AREA FRIDAY BEFORE A WEAK
DISTURBANCE MOVES ACROSS THE AREA FRIDAY NIGHT INTO SATURDAY
BRINGING A SLIGHT CHANCE FOR RAIN AND SNOW SHOWERS. AN UNSETTLED
NORTHWEST FLOW ALOFT WILL PREVAIL OVER THE WEEKEND RESULTING IN A
SLIGHT SHOWER CHANCE SATURDAY. LEE-SIDE TROUGHING SETS UP SUNDAY
BEFORE A COLD FRONT MOVES THROUGH MONDAY. TIGHT PRESSURE GRADIENTS
WILL BE ACROSS THE BEARTOOTH/ABSAROKA FOOTHILLS SUNDAY SHIFTING
EAST MONDAY RESULTING IN WINDY PERIODS ACROSS THE AREA.

A CONTINUOUS FLOW OF MOISTURE OFF THE PACIFIC WILL MOVE ACROSS
IDAHO INTO MONTANA SUNDAY INTO MONDAY BRINGING CHANCES FOR SHOWERS
ACROSS THE PLAINS WITH SNOW LIKELY FOR THE MOUNTAINS. THERE WILL
BE A BRIEF BREAK TUESDAY BEFORE THE NEXT STORM SYSTEM IMPACTS OUR
FORECAST AREA WEDNESDAY AND THURSDAY. MODELS ARE IN PRETTY GOOD
AGREEMENT IN CARVING OUT A LARGE TROUGH ACROSS THE NORTHERN
ROCKIES WEDNESDAY AND THURSDAY...AS WELL AS PLACING AN UPPER LOW
IN OUR VICINITY. FORECASTER CONFIDENCE IS HIGH FOR A CHRISTMAS
SNOW EVENT BUT DETAILS SUCH AS SNOW AMOUNTS ARE UNCERTAIN AT THIS
TIME. HOOLEY
&&

.AVIATION...

LOW CEILINGS ALONG WITH AREAS OF DENSE FOG WILL CONTINUE TO POSE
AN AVIATION HAZARD THROUGH THIS MORNING. MVFR TO IFR CONDITIONS
WILL PREVAIL WITH AREAS OF LIFR FROM KSHR TO KBIL THROUGH 18Z. THE
EXCEPTION WILL BE THE KLVM AREA AND ADJACENT FOOTHILLS WHERE VFR
CONDITIONS WILL PREVAIL. THE MOUNTAINS WILL BE OBSCURED AT TIMES
THROUGHOUT THE DAY. HOOLEY/REIMER



&&

.PRELIMINARY POINT TEMP/POPS...

    TDY THU     FRI     SAT     SUN     MON     TUE
-------------------------------------------------------
BIL 033 023/039 023/038 027/042 026/044 035/047 027/041
    2/J 00/B    00/B    11/B    23/W    33/W    32/W
LVM 036 022/041 024/040 026/043 026/041 036/047 027/043
    3/J 01/N    11/B    21/N    23/W    33/W    33/W
HDN 031 015/037 016/037 020/040 019/041 029/044 023/040
    2/J 10/B    00/B    01/B    12/J    33/W    32/W
MLS 028 017/036 019/037 019/039 022/041 029/043 023/039
    2/J 10/B    00/B    11/B    12/J    23/W    11/B
4BQ 029 016/039 017/040 017/041 020/043 030/045 024/041
    2/J 10/B    00/B    11/B    12/J    23/W    21/B
BHK 022 015/034 018/037 017/039 020/040 027/041 021/037
    2/J 20/B    10/B    01/B    11/B    22/W    11/B
SHR 032 016/038 016/038 019/040 019/041 028/043 022/040
    2/J 00/B    10/B    12/J    12/J    34/W    32/W

&&

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...DENSE FOG ADVISORY IN EFFECT UNTIL 11 AM MST THIS MORNING FOR
      ZONE 99.

&&

$$
WEATHER.GOV/BILLINGS



AREA FORECAST DISCUSSION...UPDATED

NWS NORTH PLATTE NE

 525 PM CST THU DEC 18 2014

.SYNOPSIS...
ISSUED AT 307 PM CST THU DEC 18 2014

H5 ANALYSIS FROM THIS MORNING REMAINED ACTIVE ACROSS THE
LOWER 48 STATES. A CLOSED LOW WAS PRESENT ALONG THE MAINE ATLANTIC
COAST. FURTHER WEST...A SHORTWAVE WAS NOTED OVER CENTRAL SOUTH
DAKOTA...WITH A SECOND SHORTWAVE OVER CENTRAL KS AND A THIRD SHORTWAVE
OVER SWRN AZ. HT FALLS OF 50 TO 80 METERS...IN ASSOCIATION WITH THE
DISTURBANCE IN KANSAS...WERE NOTED OVER MISSOURI AND NRN OK. SOUTH
OF THE KANSAS DISTURBANCE...A 50 TO 70 KT JET STREAK EXTENDED FROM
SERN NM INTO THE MID ATLANTIC AND CANADIAN MARITIMES. AT THE
SURFACE...FOG AND STRATUS DOMINATED CENTRAL AND EASTERN PORTIONS OF
THE FORECAST AREA TDY WITH SOME CLEARING NOTED IN THE EASTERN
NEBRASKA PANHANDLE...AS WELL AS THE WESTERN SANDHILLS AND FAR SWRN
NEBRASKA. TEMPERATURES AS OF 3 PM CST RANGED FROM 27 AT AINSWORTH
AND VALENTINE TO 30 AT THEDFORD.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 307 PM CST THU DEC 18 2014

THE MAIN FORECAST CONCERNS OVER THE SHORT TERM ARE THE TEMPERATURES
AND THE POTENTIAL FOR FOG FORMATION.

IN ASSOCIATION WITH THE MOIST RETURN FLOW FROM THE SURFACE HIGH
PRESSURE SITUATED OVER THE UPPER MIDWEST...LOW STRATUS WILL CONTINUE
MOVING SLOWLY EASTWARD THIS EVENING AND TONIGHT ACROSS THE FORECAST
AREA. RELATIVELY DRIER AIR ASSOCIATED WITH A WEST WIND MOVES INTO THE
PANHANDLE AND FAR WESTERN COUNTIES TONIGHT...KEEPING THE SKY
RELATIVELY CLOUD FREE. THE 18/12Z MODEL RUNS...ESPECIALLY THE NAM
AND RAP...AND CURRENT TRENDS IN THE VISIBLE SATELLITE IMAGES BRING
THE BACK EDGE OF THE STRATUS TO THE HIGHWAY 83 CORRIDOR BY 19/00Z.
LIGHT WINDS AND A CLEARING SKY WILL ALLOW THE ATMOSPHERE TO DECOUPLE
OVERNIGHT...AND WITH DEW POINT DEPRESSIONS GENERALLY THREE DEGREES
OR LESS...FOG FORMATION IS FAVORABLE ALONG THE EDGE OF THE STRATUS
DECK. MIN TEMPS HAVE BEEN ADJUSTED DOWNWARD FROM THE PREVIOUS
FORECAST WEST OF HIGHWAY 83 TO ACCOUNT FOR THE DECOUPLING AND AN
EXISTING SNOW PACK IN MANY LOCATIONS. OVER NORTH CENTRAL NEBRASKA...WHERE
STRATUS IS EXPECTED TO REMAIN THROUGH THE NIGHT...HAVE KEPT MIN
TEMPS A FEW DEGREES WARMER.

FRIDAY...ANY FOG SHOULD BURN OFF BY 19/15Z AND MAX TEMPS WILL REFLECT
THE AMOUNT OF CLOUD COVER. DESPITE MOSTLY CLEAR SKIES AND WEST WINDS
FOR THE WESTERN 2/3 OF THE FORECAST AREA...HIGHS WILL STILL BE IN
THE UPPER 30S TO LOWER 40S AS 850HPA TEMPS STRUGGLE TO REACH 5C.
MODELS ARE CONSISTENT WITH KEEPING THE STRATUS FARTHER EAST...AND
HIGHS WILL STAY IN THE LOWER TO MID 30S. NOT LOOKING AT A DRIZZLE
THREAT AS FORECAST SOUNDINGS INDICATE RELATIVELY DRIER AIR RIGHT AT
THE SURFACE...TOO THIN OF A MOISTURE BAND...AND NO LIFT IN THE
NEAR SURFACE CLOUD LAYER.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 307 PM CST THU DEC 18 2014

MID RANGE...FRIDAY NIGHT THROUGH SUNDAY...IN THE MID
RANGE PERIODS...THE MAIN FORECAST CHALLENGE IS TEMPERATURES. FOR
FRIDAY NIGHT...BOTH THE LATEST NAM AND GFS SOLNS POSITION THE
WESTERN EDGE OF THE STRATUS DECK FROM SARGENT UP TO NAPER AT 00Z
SATURDAY. BY 12Z SATURDAY...THIS LINE EXTENDS ROUGHLY ALONG THE FAR
NERN BORDER OF THE FORECAST AREA. AS HAS BEEN THE CASE OVER THE PAST
COUPLE OF NIGHTS...THE WESTERN FRINGES OF THE STRATUS DECK IS WHERE
FOG WAS MOST PREVALENT. WITH LIGHT WINDS EXPECTED FRIDAY
NIGHT...DECIDED TO INSERT SOME PATCHY FOG ACROSS OUR FAR
NORTHEASTERN 4 COUNTIES. ELSEWHERE...CLEAR SKIES AND COLD TEMPS ARE
EXPECTED. WITH THE LIGHT WEST NORTHWESTERLY WINDS FORECAST ACROSS
SWRN NEBRASKA...DECIDED TO GO WITH SLIGHTLY COLDER LOWS IN THE
PLATTE RIVER VALLEY. ON SATURDAY...A WEAK SURFACE TROUGH WILL PUSH
EAST INTO THE CENTRAL SANDHILLS AND NORTH CENTRAL NEBRASKA. WITH
MOSTLY CLEAR SKIES...LIGHT WESTERLY WINDS AND H85 TEMPS IN THE LOW
SINGLE DIGITS ABOVE ZERO...HIGHS WILL REACH THE LOWER 40S...WITH
SOME MID AND UPPER 30S IN THE FAR NORTHEAST...WHERE STRATUS AND FOG
WILL BE POSSIBLE SATURDAY MORNING. FOR SATURDAY NIGHT AND
SUNDAY...LIGHT WESTERLY WINDS AND MOSTLY CLEAR SKIES ARE EXPECTED.
WITH THE EXCEPTION OF THE VALLEYS...WESTERLY WINDS SHOULD KEEP THE
BL SOMEWHAT MIXED SAT NIGHT. THIS WILL RESULT IN LOWS IN THE LOWER
20S WITH SOME TEENS POSSIBLE IN THE PLATTE VALLEY. SUNDAY WILL BE
THE WARMEST DAY OF THE PERIOD. WESTERLY WINDS WILL INCREASE AHEAD OF
AN APPROACHING COLD FRONT. SOUTH OF THE FRONT...H85 TEMPS WILL
INCREASE TO 3 TO 7C SUNDAY AFTERNOON...EQUATING TO HIGHS IN THE 40S
AND LOWER 50S. DECIDED TO UNDER CUT THIS A TAD BASED ON EXPECTED
RESIDUAL SNOW COVER AND THE THREAT FOR MID AND HIGH LEVEL CLOUDINESS
AS INDICATED IN THE GFS AND NAM H700-H500 RH PROGS.

SUNDAY NIGHT THROUGH CHRISTMAS DAY...FOR THE EXTENDED
PERIODS...PRECIPITATION CHANCES MONDAY-MONDAY NIGHT...FOLLOWED BY
PRECIPITATION CHANCES CHRISTMAS EVE NIGHT AND CHRISTMAS DAY WILL
HIGHLIGHT THE EXTENDED PERIODS. FOR MONDAY-MONDAY NIGHT...AN UPPER
LEVEL TROUGH OF LOW PRESSURE WILL DROP SOUTH FROM THE EASTERN
DAKOTAS INTO THE UPPER MIDWEST. AT THE SAME TIME ANOTHER...SEPARATE
UPPER LEVEL DISTURBANCE WILL DROP SOUTH ACROSS THE NORTHERN AND
CENTRAL ROCKIES. WITH BOTH THE GFS AND ECMWF SOLNS...SUFFICIENT LIFT
AND MOISTURE EXISTS WITH BOTH SYSTEMS TO PRODUCE PRECIPITATION.
ATTM...FEEL MORE CONFIDENT IN PRECIP CHANCES IN NORTHERN AND
NORTHEASTERN NEBRASKA IN ASSOCIATION WITH THE FIRST DISTURBANCE
MENTIONED ABOVE. ATTM THERE ARE SOME SUBTLE DIFFERENCES WITH THE
UPPER LEVEL JET STRUCTURE WITH THE WESTERN DISTURBANCE. THE ECMWF IS SLIGHTLY
FURTHER WEST WITH THE JET COMPARED TO THE GFS SOLN MONDAY...WHICH
FAVORS PRECIPITATION OVER THE ROCKIES VS. THE NEBR PANHANDLE AND FAR
SWRN CWA. ON TUESDAY AND THE FIRST HALF OF WEDNESDAY...THE FORECAST
AREA WILL BE BETWEEN SYSTEMS WITH MAINLY DRY CONDS EXPECTED. BY
MIDWEEK...A STRONG UPPER LEVEL TROUGH WILL DROP SOUTH INTO
IDAHO...UTAH AND NEVADA. THIS FEATURE WILL MIGRATE TO THE EAST
SOUTHEAST ON CHRISTMAS DAY. INCREASED MID LEVEL FRONTOGENESIS WILL
DEVELOP BEHIND AN EXITING ARCTIC FRONT CHRISTMAS DAY...WHICH WILL
LEAD TO INCREASED CHANCES FOR SNOW ACROSS THE FORECAST AREA. WITH
GOOD MODEL AGREEMENT NEXT WEEK...CONFIDENCE CONTINUES TO INCREASE IN
PRECIP CHANCES FOR CHRISTMAS DAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 524 PM CST THU DEC 18 2014

THE NAM...RAP AND BOTH HRRR MODELS SHOW LIFR DEVELOPING THIS
EVENING AT KLBF WHILE JUST ONE MODEL SHOWS THE SAME AT KVTN. THE
FORECAST IS FOR CLEARING AT LBF THIS EVENING FOLLOWED BY FOG
DEVELOPMENT AND IFR. AS INDICATED BY THE 4 MODELS...IFR/LIFR
WOULD BECOME WIDESPREAD OVERNIGHT ALONG AND EAST OF HIGHWAY 83
INCLUDING AREAS NEAR KOGA. IMPROVEMENT TO VFR ACROSS ALL AREAS IS
EXPECTED AROUND 18Z. VFR IS GENERALLY EXPECTED WEST OF HIGHWAY 61
TONIGHT AND FRIDAY.

THERE IS A CHANCE THAT LIFR WILL SET IN AT KLBF THIS EVENING AND
REMAIN IN PLACE THROUGH 14Z-16Z FRIDAY AS SHOWN BY THE RAP...NAM
AND HRRR MODELS. FOR NOW THE FORECAST IS FOR BETTER CONDITIONS
GIVEN THAT THESE MODELS TEND TO OVERFORECAST VISIBILITY
RESTRICTIONS AND THERE ARE SOME MIDLEVEL CLOUDS FORECAST TO MOVE
OVERHEAD TONIGHT WHICH COULD AFFECT THE RADIATION CONDITION
NECESSARY FOR DENSE FOG AND LIFR.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CLB
SHORT TERM...DS
LONG TERM...CLB
AVIATION...CDC






AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

 326 PM CST WED DEC 17 2014

.SYNOPSIS...
ISSUED AT 325 PM CST WED DEC 17 2014

AN ACTIVE H5 PATTERN CONTINUES ACROSS THE LOWER 48 TDY
WITH NUMEROUS DISTURBANCES AND A CLOSED LOW NOTED OVER THE CONUS.
CLOSED LOW PRESSURE WAS NOTED OVER LAKE HURON AND EXTENDED WWD INTO
NRN WISCONSIN. HIGH PRESSURE WAS NOTED OVER NRN MANITOBA. ACROSS THE
WESTERN HALF OF THE CONUS...SHORTWAVES WERE NOTED OVER SERN
MT....SWRN NEW MEXICO...AND THE CALIFORNIA DESERT. HT FALLS OF 50 TO
70 METERS EXTENDED FROM EASTERN ARIZONA INTO SWRN KS. IN ASSOCIATION
WITH THE CLOSED LOW OVER THE GREAT LAKES...A NICE 50 TO 90 KT JET
STREAK EXTENDED FROM THE MID MISSOURI RIVER...EAST TO VIRGINIA AND
NORTH CAROLINA. HT FALLS IN ASSOCIATION WITH THE CLOSED LOW WERE
MOST PRONOUNCED OVER NEW ENGLAND...WHERE 50 TO 120 METER FALLS WERE
NOTED. AT THE SURFACE...ARCTIC HIGH PRESSURE WAS ANCHORED ACROSS THE
EASTERN DAKOTAS...SSE INTO MISSOURI. WEST OF THIS FEATURE...WEAK
SERLY WINDS WERE NOTED ALONG WITH PESKY LOW LEVEL CLOUDINESS AND
PATCHY FOG. TEMPERATURES THIS AFTERNOON WERE COLD WITH READINGS IN
THE LOWER 20S ACROSS WESTERN AND NORTH CENTRAL
NEBRASKA.

&&

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 325 PM CST WED DEC 17 2014

DESPITE THE MAIN UPPER PV ANOMALY AND ASSOCIATED LARGE SCALE FORCING
IS SOUTH OF THE AREA AND MOVING EASTWARD...SEVERAL FORECASTING
ISSUES REMAIN. THE STRATUS LAYER IS WARM ENOUGH TO CONTAIN
SUPERCOOLED LIQUID AND HENCE FALL TO THE GROUND IN WEAK UPSLOPE FLOW
AS FREEZING DRIZZLE IN SOME AREAS OF SOUTHWEST NEBRASKA THIS
AFTERNOON. RAP BUFR SOUNDINGS SUGGEST MINIMAL LIFT THROUGH THE
REMAINING AFTERNOON HOURS...BUT INCREASING SLIGHTLY THIS EVENING AND
OVERNIGHT. IR SAT PICS SHOW MID LEVEL CLOUDS TRYING TO MOVE OVER THE
TOP OF THE EXISTING LOW LEVEL STRATUS BUT HAVING A HARD TIME AS MID
LEVELS ARE QUITE DRY INITIALLY. BELIEVE THE INCREASING UPWARD
VERTICAL MOTION AS A RESULT OF WEAK MID LEVEL FRONTOGENESIS WILL
EVENTUALLY HELP TO MOISTEN THE MID LEVELS...BUT SOUNDINGS STILL SHOW
TOO MUCH DRY AIR TO CONNECT A SATURATED SNOW PRODUCING LAYER WITH
THE MOIST LOW LEVELS BELOW. THE END RESULT...BASED ON FORECAST
SOUNDINGS...WILL BE FREEZING DRIZZLE ESPECIALLY ACROSS THE SOUTHWEST
PORTION OF NEBRASKA THIS EVENING AND DURING THE OVERNIGHT. NEAR TERM
ENSEMBLES SUGGEST THE POSSIBILITY OF A SMALL BAND OF LIGHT SNOW FROM
SOUTHEAST FRONTIER COUNTY NORTHEASTWARD INTO CUSTER...BUT CONFIDENCE
IN SUCH A SMALL SCALE FEATURE BEING ABLE TO FULLY SATURATE THE
ATMOSPHERIC COLUMN TO SUPPORT LIGHT SNOW IS NOT HIGH...SO HAVE LEFT
PRECIPITATION MENTION AS FREEZING DRIZZLE FOR NOW.

FURTHER NORTH AND WEST...SOUTHERLY AND SOUTHEASTERLY WINDS WILL
CONTINUE TO SUSTAIN MOIST LOW LEVELS IN THE EASTERN PANHANDLE...BUT
MID AND UPPER LEVEL DRYING WILL BE GREATER HERE WHICH LEAVES A
BETTER SCENARIO FOR FOG AND HAVE THEREFORE INCLUDED THAT MENTION
THERE INTO THE MORNING HOURS. FOG WILL BE OCCURRING IN SNOW COVERED
AREAS WHICH WILL MEAN SOME DEPOSITION ON ROADS WILL BE POSSIBLE SO
THE MENTION OF FREEZING FOG WAS INCLUDED.

TOMORROW AFTERNOON CLOUDS WILL THIN ALTHOUGH STILL HAVE MUCH OF THE
AREA WITH A SNOW PACK. THIS WILL LIMIT THE ABILITY TO WARM...WITH
TEMPS STRUGGLING TO REACH FREEZING. SOME PARTIAL SUN IS EXPECTED
ACROSS WESTERN NEBRASKA THANKS TO SOME WESTERLY DOWNSLOPING WINDS
WHICH IS WHERE FORECAST HIGHS ARE THE WARMEST.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 325 PM CST WED DEC 17 2014

MID RANGE...THURSDAY NIGHT THROUGH SATURDAY...THE MAIN
FORECAST CHALLENGES IN THE MID RANGE ARE THE THREAT FOR FREEZING
DRIZZLE THURSDAY NIGHT INTO FRIDAY MORNING...AS WELL AS CLOUD COVER
AND TEMPERATURES. FOR THURSDAY NIGHT...WITH THE EXCEPTION OF THE FAR
NORTHWESTERN CWA...LOW CLOUDS AND AN ARCTIC DRAPE WILL REMAIN
ENTRENCHED ACROSS THE BULK OF THE FORECAST AREA. BOTH THE NAM AND
GFS SOLNS THIS MORNING PER FCST SOUNDINGS ARE INDICATING A NICE
LAYER OF NEAR 100 PERCENT RH FROM THE SURFACE TO 1000 TO 1500FT AGL.
WITHIN THIS LAYER...WEAK VEERING OF THE WINDS ARE PRESENT ALONG WITH
SOME WEAK OMEGA AND TEMPERATURES RANGING FROM ZERO TO -5C IN THIS
MOIST LAYER. IN ADDITION...WARMING AND DRYING IS INDICATED PER
FORECAST SOUNDINGS ABOVE THE MOIST LAYER DURING THE PERIOD. ALL
TOLD...THIS IS A DECENT SETUP FOR FREEZING DRIZZLE AND HAVE
INTRODUCED IT IN THE GRIDS. DURING THE EVENING HOURS...WITH THE
EXCEPTION OF THE PANHANDLE COUNTIES AND FAR NORTHWEST...CONDS WILL
BE FAVORABLE FOR FZDZ. THIS AREA WILL SHRINK EAST INTO THE OVERNIGHT
HOURS AND MORNING PERIOD FOR FRIDAY. BY FRIDAY AFTERNOON...MOSTLY
CLEAR SKIES IN THE CENTRAL AND WEST...AND PARTLY CLOUDY SKIES IN THE
EAST ARE EXPECTED. THIS WILL ALLOW TEMPS TO REACH THE LOWER TO
MIDDLE 30S FRIDAY...EFFECTIVELY ENDING THE FREEZING DRIZZLE THREAT.
ON FRIDAY NIGHT AND SATURDAY...FORECAST SOUNDINGS OVER THE EASTERN
THIRD OF THE FORECAST AREA ARE INDICATIVE OF ANOTHER EPISODE OF
FREEZING DRIZZLE LATE FRIDAY NIGHT INTO SATURDAY MORNING. ATTM...THE
THREAT FOR FREEZING DRIZZLE IS INDICATED ONLY IN THE NAM SOLN AS THE
GFS IS MORE AGGRESSIVE IN PUSHING THE ARCTIC AIRMASS EAST FRIDAY
NIGHT. GIVEN THE MODEL DIFFERENCES...WILL HOLD OFF ON MENTION OF
FREEZING DRIZZLE ATTM. ON SATURDAY...AN UPPER LEVEL DISTURBANCE
ACROSS THE NRN TIER OF STATES...WILL FORCE WARMER AIR INTO THE
FORECAST AREA...FOLLOWED BY A WEAK COOL FRONT SATURDAY NIGHT. LIGHT
WESTERLY WINDS SATURDAY WILL PUSH HIGHS INTO THE LOWER 40S.

SUNDAY THROUGH WEDNESDAY...AS THE UPPER LEVEL SYSTEM PUSHES EAST
MONDAY AND MONDAY NIGHT...THERE WILL BE AN INCREASED THREAT FOR LIGHT
PRECIPITATION IN THE FAR NORTHEAST...ALONG WITH A THREAT FOR
PRECIPITATION ACROSS THE CENTRAL AND NORTHERN ROCKIES...WHICH WILL
BE ENHANCED BY A STRONG UPPER LEVEL JET STREAK. BEYOND MONDAY
NIGHT...A DRY AND COLDER FORECAST IS EXPECTED ACROSS WESTERN AND
NORTH CENTRAL NEBRASKA AS ARCTIC AIR PUSHES SOUTH TUESDAY INTO
WEDNESDAY. ATTM...THE BEST THREAT FOR SNOW WILL BE OFF TO THE WEST
OF THE FORECAST AREA...HOWEVER...WE WILL NEED TO MONITOR NEXT
THURSDAY INTO NEXT WEEKEND AS THE LATEST ECMWF SOLN DIGS A DEEP
TROUGH INTO THE INTERMOUNTAIN WEST BY DAY 10.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1200 AM CST WED DEC 17 2014

PREVAILING WIDESPREAD LOW STRATUS WITH A CHANCE FOR SOME PATCHY
FREEZING DRIZZLE AND/OR LIGHT SNOW ACROSS SOUTHWEST NEBRASKA THE
NEXT 24 HOURS. GENERALLY IFR OR BELOW CIGS ACROSS THE AREA TO
PERSIST THROUGH 18Z TOMORROW. A WEAK DISTURBANCE WILL LIFT ACROSS
KANSAS AND EASTERN NEBRASKA OVERNIGHT WITH SOME WEAK LIFT AND
LIGHT SNOW POSSIBLE ACROSS SOUTHWEST NEBRASKA. A DRY LAYER ABOVE
THE MOIST BOUNDARY LAYER MAY RESULT IN SOME PATCHY FREEZING
DRIZZLE INSTEAD OF LIGHT SNOW...ESPECIALLY ON THE NW SIDE OF THE
SIDE WHICH IS WHERE KLBF IS LIKELY TO END UP...AND WILL HAVE TO
BE MONITORED. IN ADDITION TO THE STRATUS...WILL SEE LOCAL AREAS OF
FOG WITH VISIBILITIES AT TIMES DOWN TO 3SM OR LESS.


&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CLB
SHORT TERM...MASEK/JWS
LONG TERM...CLB
AVIATION...MASEK







AREA FORECAST DISCUSSION

NWS LAS VEGAS NV

 250 PM PST WED DEC 17 2014

.SYNOPSIS...SCATTERED LIGHT RAIN SHOWERS AND MOUNTAIN SNOW SHOWERS
WILL DIMINISH OVERNIGHT AS A WEATHER SYSTEM SLOWLY MOVES ACROSS THE
DESERT SOUTHWEST. IMPROVING CONDITIONS ARE EXPECTED THURSDAY AND
FRIDAY. A FEW SHOWERS WILL BE POSSIBLE ACROSS THE GREAT BASIN OVER
THE WEEKEND FOLLOWED BY DRY AND WARMER WEATHER NEXT WEEK.
&&

.SHORT TERM...EXTENSIVE LOW TO MID LEVEL CLOUDS WERE APPARENT FROM
SATELLITE LOOPS AND SURFACE OBSERVATIONS ACROSS THE FORECAST AREA
AND THESE WILL BE SLOW TO CLEAR OUT TONIGHT THROUGH THURSDAY. RECENT
RADAR LOOPS SHOWED A SLIGHT UPWARD TREND IN SCATTERED SHOWERS ACROSS
SOUTHERN CLARK AND CENTRAL MOHAVE COUNTIES EARLY THIS AFTERNOON AND
THE HRRR MODEL INDICATES THIS WILL BE THE PRIMARY AREA FOR
PRECIPITATION THROUGH EARLY THIS EVENING. ANY ADDITIONAL SNOW
AMOUNTS IN THE MOUNTAINS OF SOUTHERN NEVADA AND NORTHWEST ARIZONA
ARE EXPECTED TO BE VERY LIGHT AND THE WINTER WEATHER ADVISORY HAS
BEEN CANCELLED. THE MEAN TROUGH OVER THE REGION WILL DIG A
LITTLE TONIGHT AS A SHORTWAVE WEST OF POINT CONCEPTION DIVES TOWARD
NORTHERN BAJA. AN ADDITIONAL BAND OF MOISTURE ASSOCIATED WITH THIS
SHORTWAVE WILL MOVE INTO THE SOUTHERN SIERRA OVERNIGHT AND WILL
PRODUCE A CHANCE OF VERY LIGHT SNOW OVER THE EASTERN SLOPES...SO
POPS WERE INCREASED ACCORDINGLY.

THE TROUGH AXIS WILL SHIFT EASTWARD THURSDAY WITH GRADUAL CLEARING
THURSDAY AFTERNOON THROUGH THURSDAY NIGHT. LITTLE CHANGE IN
TEMPERATURES CAN BE EXPECTED.
&&

.LONG TERM...FRIDAY THROUGH TUESDAY.

MEDIUM RANGE MODELS SIMILAR TO 24 HOURS AGO INDICATING MOST OF THE
ENERGY ASSOCIATED WITH NEXT SHORTWAVE TROUGH WILL AFFECT CENTRAL
NEVADA NORTHWARD FRIDAY NIGHT INTO SATURDAY. WITH THAT SAID, LEFT IN
SLIGHT CHANCE POPS FROM NORTHERN INYO COUNTY EASTWARD TO NORTHERN
LINCOLN COUNTY TO ACCOUNT FOR ANY POTENTIAL SOUTHWARD SHIFT.

SUNDAY THROUGH TUESDAY THE LONGWAVE PATTERN WILL BE DOMINATED BY A
STRONG RIDGE ALONG THE WEST COAST WITH A TROUGH EAST OF THE ROCKIES.
SOUTHERN GREAT BASIN/MOJAVE DESERT WILL LIE UNDER A DRY NORTHWEST
FLOW. SURFACE HIGH DEVELOPING OVER THE NORTHERN GREAT BASIN WILL
LEAD TO AN INCREASE IN NORTH BREEZES DOWN THE COLORADO RIVER VALLEY
SOUTH OF HOOVER DAM SUNDAY-TUESDAY.
&&

.AVIATION...FOR MCCARRAN...CEILINGS BETWEEN 3K-6K FEET AROUND WILL
PERSIST THROUGH EARLY EVENING THEN HOVER AROUND 6 KFT BEFORE
PARTIALLY CLEARING AND LIFTING TO AROUND 10 KFT THURSDAY MORNING.
GENERALLY LIGHTS WINDS WILL CONTINUE TONIGHT.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...CEILINGS OF 3K-5K FT AND MOUNTAIN OBSCURATION WILL
CONTINUE ACROSS MUCH OF THE REGION TONIGHT THROUGH THURSDAY MORNING
FOLLOWED BY PARTIAL CLEARING AS A WEAK WEATHER SYSTEM GRADUALLY
MOVES TO THE EAST.
&&

.SPOTTER INFORMATION STATEMENT...SPOTTERS ARE ENCOURAGED TO REPORT
ANY SIGNIFICANT WEATHER CONDITIONS TODAY THROUGH THURSDAY ACCORDING
TO STANDARD OPERATING PROCEDURES.
&&

$$

SHORT TERM/AVIATION...ADAIR
LONG TERM...PIERCE

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER









AREA FORECAST DISCUSSION...UPDATED

NWS ALBUQUERQUE NM

 1049 AM MST WED DEC 17 2014

.AVIATION...
18Z TAF CYCLE
ATMOSPHERIC MOISTURE HAS INCREASED SIGNIFICANTLY IN ADVANCE OF TWO
UPPER LEVEL DISTURBANCES AND IS RESULTING IN AREAS OF SNOW...
OCCASIONAL IFR CONDITIONS AND WIDESPREAD MOUNTAIN OBSCURATIONS.
IMPROVEMENT ALREADY OBSERVED THOUGH...WITH TERMINALS IMPACTED
EARLIER TRENDING UP INTO MVFR AND VFR CATEGORIES. CONDITIONS
SHOULD DETERIORATE THIS EVENING...ESPECIALLY AT KGUP WITH THE
ONSET OF ANOTHER ROUND OF SNOW. ELSEWHERE ACROSS CENTRAL AND
WESTERN PORTIONS OF THE AREA...MVFR IMPACTS ARE POSSIBLE...MOST
LIKELY AT KSAF. KROW AND KLVS LOOK TO REMAIN VFR THROUGH THE NEXT
24HRS...WHILE IFR CONDITIONS ARE POSSIBLE THURSDAY MORNING AT KTCC
WITH THE PASSAGE OF A WEAK BACKDOOR COLD FRONT.

11

&&

.UPDATE...
UPDATED FORECAST TO INCLUDE SANTA FE METRO AND THE LOWER CHAMA
RIVER VALLEY INCLUDING ESPANOLA TO THE WINTER WEATHER ADVISORY
THROUGH THIS EVENING. VALLEY AREAS IN AND AROUND ESPANOLA RADIATIVELY
COOLED LAST NIGHT SO SNOW LEVELS ARE LOWER THERE. ALSO RAISED
PRECIPITATION CHANCES FROM EASTERN CIBOLA COUNTY EAST AND
NORTHEASTWARD TO CENTRAL SANGRE DE CRISTOS UNDERNEATH AND ON THE
BACKSIDE OF THE MAIN VORT CENTER/CIRCULATION.

33

&&

.PREV DISCUSSION...312 AM MST WED DEC 17 2014...
.SYNOPSIS...
SEVERAL UPPER LEVEL DISTURBANCES TODAY AND THURSDAY WILL BRING
MUCH NEEDED PRECIPITATION TO THE LAND OF ENCHANTMENT. MUCH OF THE
PRECIPITATION WILL FAVOR WESTERN...AND PERHAPS TO SOME
EXTENT...CENTRAL NEW MEXICO. 1 TO 3 INCH SNOW AMOUNTS WILL BE
COMMON ABOVE 6000 FEET...WITH 3 TO 5 INCHES ACROSS THE HIGHER
TERRAIN. AFTER THE LAST SYSTEM EXITS THE STATE THURSDAY NIGHT...A
MUCH QUIETER FRIDAY WILL PREVAIL...BUT TEMPERATURES WILL REMAIN
CHILLY. MODELS ARE BACKING OFF ON PRECIPITATION POTENTIAL THIS
WEEKEND AND EARLY NEXT WEEK...BUT THERE IS STILL PLENTY OF TIME
FOR THAT TO CHANGE.

&&

.DISCUSSION...
AFTER MANY DIFFERENT DEPICTIONS OF TODAYS EVENT BY THE MODELS
OVER THE LAST FEW DAYS...IT APPEARS THAT THEY HAVE FINALLY COME
INTO AGREEMENT. TWO QUICK MOVING SHORTWAVE TROUGHS WILL CROSS NM
TODAY...BOTH CURRENTLY WELL DEFINED ON WATER VAPOR IMAGERY. THE
FIRST IS ASSOCIATED WITH THE LIGHTNING ACROSS NORTHERN MEXICO THIS
MORNING...WHILE THE SECOND IS ASSOCIATED WITH THE LIGHTNING OFF
THE COAST OF CALI. SHOWERS ARE ALREADY DEVELOPING AHEAD OF THE
FIRST SYSTEM IN ARIZONA AND TO SOME EXTENT WESTERN NM. THIS SYSTEM
LOOKS TO CROSS NM THIS MORNING AND EARLY THIS AFTERNOON. MOST
OPERATIONAL MODELS SHOW THE FAVORED AREA OF PRECIPITATION ACROSS
THE NW QUARTER OF NM. TEMPS ARE COLD ENOUGH FOR SOME SNOW EVEN
ACROSS THE NW PLATEAU...THUS A GOOD CALL BY THE EVENING CREW TO
ADD ZONE 501 TO THE WINTER WX ADVY. THE SECOND DISTURBANCE WILL
COME QUICKLY AFTER THE FIRST AND CROSS NM LATE THIS AFTN AND THIS
EVE. SNOW LEVELS THIS AFTN WILL RANGE FROM 5500-6000 FEET OR SO.
WHILE THE FIRST SYSTEM MAY BRING A MORE SOLID AREA OF SNOW...THE
PRECIPITATION WITH THE SECOND SYSTEM LOOKS TO BE MORE CONVECTIVE
IN NATURE...AND MAY EVEN SEE SOME ISOLATED THUNDERSTORMS THIS
AFTERNOON. AREAS ALONG AND WEST OF THE RIO GRANDE WILL GENERALLY
BE FAVORED FOR PRECIPITATION.ONE INTERESTING NOTE...HOWEVER...IS
THAT THE HRRR HAS TRENDED BACK ON PRECIPITATION OVER THE LAST
SEVERAL RUNS...AT LEAST WITH PRECIPITATION THROUGH EARLY AFTN.
WITH ALL THAT SAID...THE WINTER WX ADVYS LOOK PRETTY GOOD...THOUGH
SNOW AMOUNTS WILL CERTAINLY BE ON THE LIGHTER SIDE OF ADVISORY
CRITERIA FOR MOST AREAS.

A THIRD SHORTWAVE WILL ARRIVE ON THURSDAY...THOUGH MOST OF THE
ENERGY ASSOCIATED WITH THIS SYSTEM WILL DIVE SOUTH OF THE CWA. SOME
LIGHT SHOWERY ACTIVITY SHOULD OCCUR ACROSS THE WEST AGAIN...BUT
AMOUNTS WILL BE MINIMAL. THE SOUTHERN TIER OF THE CWA...FROM THE
SOUTHWEST MTNS TO ROOSEVELT COUNTY...WILL HAVE THE BEST CHANCES FOR
PRECIPITATION...BUT EVEN THEN...AMOUNTS WILL BE MINIMAL. COLD TEMPS
WILL KEEP SNOW LEVELS LOW...GENERALLY AOB 5500 FEET.

AFTER THE THIRD SYSTEM SLIDES EAST THURSDAY NIGHT...FRIDAY SHOULD BE
QUIET...THOUGH STILL CHILLY. MODELS ARE SHOWING A TROUGH CROSSING NM
ON SATURDAY...BUT LITTLE MOISTURE IS ASSOCIATED WITH IT SO NOT
EXPECTING PRECIP ATTM. THEREAFTER...STRONG NORTHWEST FLOW LOOKS TO
BE THE RULE. THE ECMWF IS SHOWING A DISTURBANCE WITHIN THE FLOW MAY
CLIP NE NM ON MONDAY AND MONDAY NIGHT. THIS COMBINED WITH AN
ASSOCIATED COLD FRONT MAY RESULT IN SOME LIGHT SHOWERS ACROSS THE
NORTHEAST IF THE ECMWF IS CORRECT. OTHERWISE...DRIER CONDITIONS
LOOK TO BE THE RULE THROUGH AT LEAST MID WEEK.

34

&&

.FIRE WEATHER...
MAIN FIRE WEATHER HIGHLIGHTS INCLUDE AN UNSETTLED WEATHER PATTERN
WITH SOME CHANCES OF WETTING MOISTURE ACROSS WESTERN/CENTRAL AREAS
THROUGH THURSDAY MORNING. THE WEEKEND SYSTEM JUST LOOKS TOO DRY.
GUSTIER NW WINDS AND DECENT VENTILATION IN AREAS EXPECTED SUNDAY
THROUGH EARLY NEXT WEEK.

CURRENT RADAR TRENDS SHOW SHOWER DEVELOPMENT AND SOME ORGANIZATION
IN THE PRECIPITATION FIELD OVER ARIZONA. SNOW AND LOWER ELEVATION
RAIN SHOWERS WILL SPREAD ACROSS THE WESTERN HALF OF THE AREA THROUGH
THE DAY PERIOD WITH LINGERING IMPACTS INTO THE OVERNIGHT. OROGRAPHIC
WEST FACING SLOPES LOOK TO BE FAVORED WITH THE WETTING
PRECIPITATION. EASTERN AREAS WILL SEE SCANT PRECIPITATION RESULTS.
TEMPERATURES WILL BE COOLER THAN NORMAL WITH HIGH RH VALUES FAVORING
THE WESTERN HALF. FLOW ALOFT WILL INCREASE AND WILL COMBINE WITH
RISING MIXING HEIGHTS TO PRODUCE IMPROVING VENTILATION MOST AREAS.
THE SOUTHERN HALF WILL BE THE FOCUS FOR GOOD TO EXCELLENT RATINGS.
SURFACE WINDS WILL BE BREEZY AT TIMES ACROSS THE SOUTHERN
HALF...ESPECIALLY OVER THE MOUNTAIN RIDGES/PEAKS.

A SECONDARY PACIFIC WAVE OR TROUGH WILL SLIDE OVER THE REGION ON
THURSDAY. MODELS HAVE BEEN TAKING THE MAIN PIECE OF ENERGY
ASSOCIATED WITH THE TROUGH FURTHER SOUTH SO IMPACTS TO THE FIRE WX
AREA LOOK TO BE MINIMAL AT THIS TIME. PERHAPS SOME LOCALIZED WETTING
MOISTURE ACROSS THE FAR SOUTH. EITHER WAY...HIGH TEMPERATURES WILL
REMAIN BELOW NORMAL MOST AREAS WITH HIGHER HUMIDITY READINGS. MIXING
HEIGHTS APPEAR TO BE NEAR SEASONABLE IF NOT A LITTLE HIGHER THAN
NORMAL ALTHOUGH TRANSPORT WINDS WILL LOWER COMPARED TO TODAY/S
VALUES. THUS...VENT RATES WILL LOWER. LOOKING AT A STRIP OF FAIR
CONDITIONS BETWEEN FARMINGTON TO THE ESTANCIA VALLEY BUT WOULD ONLY
BE FAIR FOR 2 TO 4 HRS MOST LOCATIONS.

AS MENTIONED ABOVE...STORM SYSTEM FOR THE WEEKEND PERIOD LOOKS TO BE
A NON EVENT. THERE WILL BE A PACIFIC WAVE CAUGHT IN NW FLOW MOVING
OVER THE AREA SATURDAY NIGHT. STRENGTHENING NW FLOW WILL BE FOUND ON
THE BACKSIDE OF THE WAVE AND PROVIDE SOME BREEZES ON SUNDAY.
ESPECIALLY IMPACTING THE MT TAYLOR TO CLINES CORNER AREA. SURFACE
WINDS ON SATURDAY APPEAR TO BE LIGHT. VENTILATION RATES ON SATURDAY
LOOK TO BE ON THE LOWER SIDE WITH SOME FAIR TO GOOD CONDITIONS
GENERALLY LASTING A FEW HRS.

MODELS CONTINUE TO SHOW A GUSTIER NW FLOW DEVELOPING OVER THE AREA
DURING THE EARLIER HALF OF NEXT WEEK. VENTILATION RATES SHOULD
IMPROVE IN AREAS DUE TO THE HIGHER TRANSPORT WINDS BUT LOWER MIXING
HEIGHTS WILL PRESENT SOME OF THE AREA FROM GETTING INTO THE
FAIR/GOOD TO EXCELLENT READINGS. SUSPECT VENT RATE VALUES WILL
ADJUST SOME AS THE FLOW ADJUSTS. THE FLOW DOES LOOK TO BE DRIER WITH
TEMPERATURES BECOMING A BIT WARMER. THE GFS IS DRY BUT THE ECMWF IS
STILL SPITTING OUT LIGHTER PRECIPITATION AMOUNTS ACROSS THE EAST ON
TUESDAY. WOULD LIKE TO SEE ANOTHER DAY OR TWO WORTH OF CONSISTENT
MODEL RUNS BEFORE TOTALLY BUYING OFF ON THIS SCENARIO.

50

&&

.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR THE
FOLLOWING ZONES...NMZ501>508-510>514-517-518.

&&

$$

33





AREA FORECAST DISCUSSION...UPDATED

NWS ALBUQUERQUE NM

 943 AM MST WED DEC 17 2014

.UPDATE...
UPDATED FORECAST TO INCLUDE SANTA FE METRO AND THE LOWER CHAMA
RIVER VALLEY INCLUDING ESPANOLA TO THE WINTER WEATHER ADVISORY
THROUGH THIS EVENING. VALLEY AREAS IN AND AROUND ESPANOLA RADIATIVELY
COOLED LAST NIGHT SO SNOW LEVELS ARE LOWER THERE. ALSO RAISED
PRECIPITATION CHANCES FROM EASTERN CIBOLA COUNTY EAST AND
NORTHEASTWARD TO CENTRAL SANGRE DE CRISTOS UNDERNEATH AND ON THE
BACKSIDE OF THE MAIN VORT CENTER/CIRCULATION.

33

&&

.PREV DISCUSSION...449 AM MST WED DEC 17 2014...
.AVIATION...
12Z TAF CYCLE
PACIFIC MOISTURE WILL CONTINUE TO STREAM OVER THE AREA DURING THE
NEXT 12 TO 24 HRS. CONDITIONS WILL DETERIORATE DURING THE MORNING
AND AFTERNOON HOURS TODAY BUT IMPROVE DURING THE OVERNIGHT. LOOK
FOR WIDESPREAD MVFR CATEGORIES ASSOCIATED WITH RAIN/SNOW. THE
HIGHER ELEVATION TERMINAL SITES SUCH AS GUP/SAF SHOULD SEE
PREDOMINATE SN WHILE OTHER SITES LIKE FMN/AEG/ABQ COULD SEE A MIX.
LOCALIZED IFR CONDITIONS EXPECTED WITH THE PRECIPITATION. AS THE
SH DIE OFF TONIGHT...SOME OF THE TERMINAL SITES COULD EXPERIENCE
REDEVELOPMENT OF LOWER CIG/VIS. THIS IS MOST LIKELY TO OCCUR AT
FMN/GUP.

50

&&

.PREV DISCUSSION...312 AM MST WED DEC 17 2014...
.SYNOPSIS...
SEVERAL UPPER LEVEL DISTURBANCES TODAY AND THURSDAY WILL BRING
MUCH NEEDED PRECIPITATION TO THE LAND OF ENCHANTMENT. MUCH OF THE
PRECIPITATION WILL FAVOR WESTERN...AND PERHAPS TO SOME
EXTENT...CENTRAL NEW MEXICO. 1 TO 3 INCH SNOW AMOUNTS WILL BE
COMMON ABOVE 6000 FEET...WITH 3 TO 5 INCHES ACROSS THE HIGHER
TERRAIN. AFTER THE LAST SYSTEM EXITS THE STATE THURSDAY NIGHT...A
MUCH QUIETER FRIDAY WILL PREVAIL...BUT TEMPERATURES WILL REMAIN
CHILLY. MODELS ARE BACKING OFF ON PRECIPITATION POTENTIAL THIS
WEEKEND AND EARLY NEXT WEEK...BUT THERE IS STILL PLENTY OF TIME
FOR THAT TO CHANGE.

&&

.DISCUSSION...
AFTER MANY DIFFERENT DEPICTIONS OF TODAYS EVENT BY THE MODELS
OVER THE LAST FEW DAYS...IT APPEARS THAT THEY HAVE FINALLY COME
INTO AGREEMENT. TWO QUICK MOVING SHORTWAVE TROUGHS WILL CROSS NM
TODAY...BOTH CURRENTLY WELL DEFINED ON WATER VAPOR IMAGERY. THE
FIRST IS ASSOCIATED WITH THE LIGHTNING ACROSS NORTHERN MEXICO THIS
MORNING...WHILE THE SECOND IS ASSOCIATED WITH THE LIGHTNING OFF
THE COAST OF CALI. SHOWERS ARE ALREADY DEVELOPING AHEAD OF THE
FIRST SYSTEM IN ARIZONA AND TO SOME EXTENT WESTERN NM. THIS SYSTEM
LOOKS TO CROSS NM THIS MORNING AND EARLY THIS AFTERNOON. MOST
OPERATIONAL MODELS SHOW THE FAVORED AREA OF PRECIPITATION ACROSS
THE NW QUARTER OF NM. TEMPS ARE COLD ENOUGH FOR SOME SNOW EVEN
ACROSS THE NW PLATEAU...THUS A GOOD CALL BY THE EVENING CREW TO
ADD ZONE 501 TO THE WINTER WX ADVY. THE SECOND DISTURBANCE WILL
COME QUICKLY AFTER THE FIRST AND CROSS NM LATE THIS AFTN AND THIS
EVE. SNOW LEVELS THIS AFTN WILL RANGE FROM 5500-6000 FEET OR SO.
WHILE THE FIRST SYSTEM MAY BRING A MORE SOLID AREA OF SNOW...THE
PRECIPITATION WITH THE SECOND SYSTEM LOOKS TO BE MORE CONVECTIVE
IN NATURE...AND MAY EVEN SEE SOME ISOLATED THUNDERSTORMS THIS
AFTERNOON. AREAS ALONG AND WEST OF THE RIO GRANDE WILL GENERALLY
BE FAVORED FOR PRECIPITATION.ONE INTERESTING NOTE...HOWEVER...IS
THAT THE HRRR HAS TRENDED BACK ON PRECIPITATION OVER THE LAST
SEVERAL RUNS...AT LEAST WITH PRECIPITATION THROUGH EARLY AFTN.
WITH ALL THAT SAID...THE WINTER WX ADVYS LOOK PRETTY GOOD...THOUGH
SNOW AMOUNTS WILL CERTAINLY BE ON THE LIGHTER SIDE OF ADVISORY
CRITERIA FOR MOST AREAS.

A THIRD SHORTWAVE WILL ARRIVE ON THURSDAY...THOUGH MOST OF THE
ENERGY ASSOCIATED WITH THIS SYSTEM WILL DIVE SOUTH OF THE CWA. SOME
LIGHT SHOWERY ACTIVITY SHOULD OCCUR ACROSS THE WEST AGAIN...BUT
AMOUNTS WILL BE MINIMAL. THE SOUTHERN TIER OF THE CWA...FROM THE
SOUTHWEST MTNS TO ROOSEVELT COUNTY...WILL HAVE THE BEST CHANCES FOR
PRECIPITATION...BUT EVEN THEN...AMOUNTS WILL BE MINIMAL. COLD TEMPS
WILL KEEP SNOW LEVELS LOW...GENERALLY AOB 5500 FEET.

AFTER THE THIRD SYSTEM SLIDES EAST THURSDAY NIGHT...FRIDAY SHOULD BE
QUIET...THOUGH STILL CHILLY. MODELS ARE SHOWING A TROUGH CROSSING NM
ON SATURDAY...BUT LITTLE MOISTURE IS ASSOCIATED WITH IT SO NOT
EXPECTING PRECIP ATTM. THEREAFTER...STRONG NORTHWEST FLOW LOOKS TO
BE THE RULE. THE ECMWF IS SHOWING A DISTURBANCE WITHIN THE FLOW MAY
CLIP NE NM ON MONDAY AND MONDAY NIGHT. THIS COMBINED WITH AN
ASSOCIATED COLD FRONT MAY RESULT IN SOME LIGHT SHOWERS ACROSS THE
NORTHEAST IF THE ECMWF IS CORRECT. OTHERWISE...DRIER CONDITIONS
LOOK TO BE THE RULE THROUGH AT LEAST MID WEEK.

34

&&

.FIRE WEATHER...
MAIN FIRE WEATHER HIGHLIGHTS INCLUDE AN UNSETTLED WEATHER PATTERN
WITH SOME CHANCES OF WETTING MOISTURE ACROSS WESTERN/CENTRAL AREAS
THROUGH THURSDAY MORNING. THE WEEKEND SYSTEM JUST LOOKS TOO DRY.
GUSTIER NW WINDS AND DECENT VENTILATION IN AREAS EXPECTED SUNDAY
THROUGH EARLY NEXT WEEK.

CURRENT RADAR TRENDS SHOW SHOWER DEVELOPMENT AND SOME ORGANIZATION
IN THE PRECIPITATION FIELD OVER ARIZONA. SNOW AND LOWER ELEVATION
RAIN SHOWERS WILL SPREAD ACROSS THE WESTERN HALF OF THE AREA THROUGH
THE DAY PERIOD WITH LINGERING IMPACTS INTO THE OVERNIGHT. OROGRAPHIC
WEST FACING SLOPES LOOK TO BE FAVORED WITH THE WETTING
PRECIPITATION. EASTERN AREAS WILL SEE SCANT PRECIPITATION RESULTS.
TEMPERATURES WILL BE COOLER THAN NORMAL WITH HIGH RH VALUES FAVORING
THE WESTERN HALF. FLOW ALOFT WILL INCREASE AND WILL COMBINE WITH
RISING MIXING HEIGHTS TO PRODUCE IMPROVING VENTILATION MOST AREAS.
THE SOUTHERN HALF WILL BE THE FOCUS FOR GOOD TO EXCELLENT RATINGS.
SURFACE WINDS WILL BE BREEZY AT TIMES ACROSS THE SOUTHERN
HALF...ESPECIALLY OVER THE MOUNTAIN RIDGES/PEAKS.

A SECONDARY PACIFIC WAVE OR TROUGH WILL SLIDE OVER THE REGION ON
THURSDAY. MODELS HAVE BEEN TAKING THE MAIN PIECE OF ENERGY
ASSOCIATED WITH THE TROUGH FURTHER SOUTH SO IMPACTS TO THE FIRE WX
AREA LOOK TO BE MINIMAL AT THIS TIME. PERHAPS SOME LOCALIZED WETTING
MOISTURE ACROSS THE FAR SOUTH. EITHER WAY...HIGH TEMPERATURES WILL
REMAIN BELOW NORMAL MOST AREAS WITH HIGHER HUMIDITY READINGS. MIXING
HEIGHTS APPEAR TO BE NEAR SEASONABLE IF NOT A LITTLE HIGHER THAN
NORMAL ALTHOUGH TRANSPORT WINDS WILL LOWER COMPARED TO TODAY/S
VALUES. THUS...VENT RATES WILL LOWER. LOOKING AT A STRIP OF FAIR
CONDITIONS BETWEEN FARMINGTON TO THE ESTANCIA VALLEY BUT WOULD ONLY
BE FAIR FOR 2 TO 4 HRS MOST LOCATIONS.

AS MENTIONED ABOVE...STORM SYSTEM FOR THE WEEKEND PERIOD LOOKS TO BE
A NON EVENT. THERE WILL BE A PACIFIC WAVE CAUGHT IN NW FLOW MOVING
OVER THE AREA SATURDAY NIGHT. STRENGTHENING NW FLOW WILL BE FOUND ON
THE BACKSIDE OF THE WAVE AND PROVIDE SOME BREEZES ON SUNDAY.
ESPECIALLY IMPACTING THE MT TAYLOR TO CLINES CORNER AREA. SURFACE
WINDS ON SATURDAY APPEAR TO BE LIGHT. VENTILATION RATES ON SATURDAY
LOOK TO BE ON THE LOWER SIDE WITH SOME FAIR TO GOOD CONDITIONS
GENERALLY LASTING A FEW HRS.

MODELS CONTINUE TO SHOW A GUSTIER NW FLOW DEVELOPING OVER THE AREA
DURING THE EARLIER HALF OF NEXT WEEK. VENTILATION RATES SHOULD
IMPROVE IN AREAS DUE TO THE HIGHER TRANSPORT WINDS BUT LOWER MIXING
HEIGHTS WILL PRESENT SOME OF THE AREA FROM GETTING INTO THE
FAIR/GOOD TO EXCELLENT READINGS. SUSPECT VENT RATE VALUES WILL
ADJUST SOME AS THE FLOW ADJUSTS. THE FLOW DOES LOOK TO BE DRIER WITH
TEMPERATURES BECOMING A BIT WARMER. THE GFS IS DRY BUT THE ECMWF IS
STILL SPITTING OUT LIGHTER PRECIPITATION AMOUNTS ACROSS THE EAST ON
TUESDAY. WOULD LIKE TO SEE ANOTHER DAY OR TWO WORTH OF CONSISTENT
MODEL RUNS BEFORE TOTALLY BUYING OFF ON THIS SCENARIO.

50

&&

.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR THE
FOLLOWING ZONES...NMZ501>508-510>514-517-518.

&&

$$

33









AREA FORECAST DISCUSSION...UPDATED

NWS ALBUQUERQUE NM

 449 AM MST WED DEC 17 2014

.AVIATION...
12Z TAF CYCLE
PACIFIC MOISTURE WILL CONTINUE TO STREAM OVER THE AREA DURING THE
NEXT 12 TO 24 HRS. CONDITIONS WILL DETERIORATE DURING THE MORNING
AND AFTERNOON HOURS TODAY BUT IMPROVE DURING THE OVERNIGHT. LOOK
FOR WIDESPREAD MVFR CATEGORIES ASSOCIATED WITH RAIN/SNOW. THE
HIGHER ELEVATION TERMINAL SITES SUCH AS GUP/SAF SHOULD SEE
PREDOMINATE SN WHILE OTHER SITES LIKE FMN/AEG/ABQ COULD SEE A MIX.
LOCALIZED IFR CONDITIONS EXPECTED WITH THE PRECIPITATION. AS THE
SH DIE OFF TONIGHT...SOME OF THE TERMINAL SITES COULD EXPERIENCE
REDEVELOPMENT OF LOWER CIG/VIS. THIS IS MOST LIKELY TO OCCUR AT
FMN/GUP.

50

&&

.PREV DISCUSSION...312 AM MST WED DEC 17 2014...
.SYNOPSIS...
SEVERAL UPPER LEVEL DISTURBANCES TODAY AND THURSDAY WILL BRING
MUCH NEEDED PRECIPITATION TO THE LAND OF ENCHANTMENT. MUCH OF THE
PRECIPITATION WILL FAVOR WESTERN...AND PERHAPS TO SOME
EXTENT...CENTRAL NEW MEXICO. 1 TO 3 INCH SNOW AMOUNTS WILL BE
COMMON ABOVE 6000 FEET...WITH 3 TO 5 INCHES ACROSS THE HIGHER
TERRAIN. AFTER THE LAST SYSTEM EXITS THE STATE THURSDAY NIGHT...A
MUCH QUIETER FRIDAY WILL PREVAIL...BUT TEMPERATURES WILL REMAIN
CHILLY. MODELS ARE BACKING OFF ON PRECIPITATION POTENTIAL THIS
WEEKEND AND EARLY NEXT WEEK...BUT THERE IS STILL PLENTY OF TIME
FOR THAT TO CHANGE.

&&

.DISCUSSION...
AFTER MANY DIFFERENT DEPICTIONS OF TODAYS EVENT BY THE MODELS
OVER THE LAST FEW DAYS...IT APPEARS THAT THEY HAVE FINALLY COME
INTO AGREEMENT. TWO QUICK MOVING SHORTWAVE TROUGHS WILL CROSS NM
TODAY...BOTH CURRENTLY WELL DEFINED ON WATER VAPOR IMAGERY. THE
FIRST IS ASSOCIATED WITH THE LIGHTNING ACROSS NORTHERN MEXICO THIS
MORNING...WHILE THE SECOND IS ASSOCIATED WITH THE LIGHTNING OFF
THE COAST OF CALI. SHOWERS ARE ALREADY DEVELOPING AHEAD OF THE
FIRST SYSTEM IN ARIZONA AND TO SOME EXTENT WESTERN NM. THIS SYSTEM
LOOKS TO CROSS NM THIS MORNING AND EARLY THIS AFTERNOON. MOST
OPERATIONAL MODELS SHOW THE FAVORED AREA OF PRECIPITATION ACROSS
THE NW QUARTER OF NM. TEMPS ARE COLD ENOUGH FOR SOME SNOW EVEN
ACROSS THE NW PLATEAU...THUS A GOOD CALL BY THE EVENING CREW TO
ADD ZONE 501 TO THE WINTER WX ADVY. THE SECOND DISTURBANCE WILL
COME QUICKLY AFTER THE FIRST AND CROSS NM LATE THIS AFTN AND THIS
EVE. SNOW LEVELS THIS AFTN WILL RANGE FROM 5500-6000 FEET OR SO.
WHILE THE FIRST SYSTEM MAY BRING A MORE SOLID AREA OF SNOW...THE
PRECIPITATION WITH THE SECOND SYSTEM LOOKS TO BE MORE CONVECTIVE
IN NATURE...AND MAY EVEN SEE SOME ISOLATED THUNDERSTORMS THIS
AFTERNOON. AREAS ALONG AND WEST OF THE RIO GRANDE WILL GENERALLY
BE FAVORED FOR PRECIPITATION.ONE INTERESTING NOTE...HOWEVER...IS
THAT THE HRRR HAS TRENDED BACK ON PRECIPITATION OVER THE LAST
SEVERAL RUNS...AT LEAST WITH PRECIPITATION THROUGH EARLY AFTN.
WITH ALL THAT SAID...THE WINTER WX ADVYS LOOK PRETTY GOOD...THOUGH
SNOW AMOUNTS WILL CERTAINLY BE ON THE LIGHTER SIDE OF ADVISORY
CRITERIA FOR MOST AREAS.

A THIRD SHORTWAVE WILL ARRIVE ON THURSDAY...THOUGH MOST OF THE
ENERGY ASSOCIATED WITH THIS SYSTEM WILL DIVE SOUTH OF THE CWA. SOME
LIGHT SHOWERY ACTIVITY SHOULD OCCUR ACROSS THE WEST AGAIN...BUT
AMOUNTS WILL BE MINIMAL. THE SOUTHERN TIER OF THE CWA...FROM THE
SOUTHWEST MTNS TO ROOSEVELT COUNTY...WILL HAVE THE BEST CHANCES FOR
PRECIPITATION...BUT EVEN THEN...AMOUNTS WILL BE MINIMAL. COLD TEMPS
WILL KEEP SNOW LEVELS LOW...GENERALLY AOB 5500 FEET.

AFTER THE THIRD SYSTEM SLIDES EAST THURSDAY NIGHT...FRIDAY SHOULD BE
QUIET...THOUGH STILL CHILLY. MODELS ARE SHOWING A TROUGH CROSSING NM
ON SATURDAY...BUT LITTLE MOISTURE IS ASSOCIATED WITH IT SO NOT
EXPECTING PRECIP ATTM. THEREAFTER...STRONG NORTHWEST FLOW LOOKS TO
BE THE RULE. THE ECMWF IS SHOWING A DISTURBANCE WITHIN THE FLOW MAY
CLIP NE NM ON MONDAY AND MONDAY NIGHT. THIS COMBINED WITH AN
ASSOCIATED COLD FRONT MAY RESULT IN SOME LIGHT SHOWERS ACROSS THE
NORTHEAST IF THE ECMWF IS CORRECT. OTHERWISE...DRIER CONDITIONS
LOOK TO BE THE RULE THROUGH AT LEAST MID WEEK.

34

&&

.FIRE WEATHER...
MAIN FIRE WEATHER HIGHLIGHTS INCLUDE AN UNSETTLED WEATHER PATTERN
WITH SOME CHANCES OF WETTING MOISTURE ACROSS WESTERN/CENTRAL AREAS
THROUGH THURSDAY MORNING. THE WEEKEND SYSTEM JUST LOOKS TOO DRY.
GUSTIER NW WINDS AND DECENT VENTILATION IN AREAS EXPECTED SUNDAY
THROUGH EARLY NEXT WEEK.

CURRENT RADAR TRENDS SHOW SHOWER DEVELOPMENT AND SOME ORGANIZATION
IN THE PRECIPITATION FIELD OVER ARIZONA. SNOW AND LOWER ELEVATION
RAIN SHOWERS WILL SPREAD ACROSS THE WESTERN HALF OF THE AREA THROUGH
THE DAY PERIOD WITH LINGERING IMPACTS INTO THE OVERNIGHT. OROGRAPHIC
WEST FACING SLOPES LOOK TO BE FAVORED WITH THE WETTING
PRECIPITATION. EASTERN AREAS WILL SEE SCANT PRECIPITATION RESULTS.
TEMPERATURES WILL BE COOLER THAN NORMAL WITH HIGH RH VALUES FAVORING
THE WESTERN HALF. FLOW ALOFT WILL INCREASE AND WILL COMBINE WITH
RISING MIXING HEIGHTS TO PRODUCE IMPROVING VENTILATION MOST AREAS.
THE SOUTHERN HALF WILL BE THE FOCUS FOR GOOD TO EXCELLENT RATINGS.
SURFACE WINDS WILL BE BREEZY AT TIMES ACROSS THE SOUTHERN
HALF...ESPECIALLY OVER THE MOUNTAIN RIDGES/PEAKS.

A SECONDARY PACIFIC WAVE OR TROUGH WILL SLIDE OVER THE REGION ON
THURSDAY. MODELS HAVE BEEN TAKING THE MAIN PIECE OF ENERGY
ASSOCIATED WITH THE TROUGH FURTHER SOUTH SO IMPACTS TO THE FIRE WX
AREA LOOK TO BE MINIMAL AT THIS TIME. PERHAPS SOME LOCALIZED WETTING
MOISTURE ACROSS THE FAR SOUTH. EITHER WAY...HIGH TEMPERATURES WILL
REMAIN BELOW NORMAL MOST AREAS WITH HIGHER HUMIDITY READINGS. MIXING
HEIGHTS APPEAR TO BE NEAR SEASONABLE IF NOT A LITTLE HIGHER THAN
NORMAL ALTHOUGH TRANSPORT WINDS WILL LOWER COMPARED TO TODAY/S
VALUES. THUS...VENT RATES WILL LOWER. LOOKING AT A STRIP OF FAIR
CONDITIONS BETWEEN FARMINGTON TO THE ESTANCIA VALLEY BUT WOULD ONLY
BE FAIR FOR 2 TO 4 HRS MOST LOCATIONS.

AS MENTIONED ABOVE...STORM SYSTEM FOR THE WEEKEND PERIOD LOOKS TO BE
A NON EVENT. THERE WILL BE A PACIFIC WAVE CAUGHT IN NW FLOW MOVING
OVER THE AREA SATURDAY NIGHT. STRENGTHENING NW FLOW WILL BE FOUND ON
THE BACKSIDE OF THE WAVE AND PROVIDE SOME BREEZES ON SUNDAY.
ESPECIALLY IMPACTING THE MT TAYLOR TO CLINES CORNER AREA. SURFACE
WINDS ON SATURDAY APPEAR TO BE LIGHT. VENTILATION RATES ON SATURDAY
LOOK TO BE ON THE LOWER SIDE WITH SOME FAIR TO GOOD CONDITIONS
GENERALLY LASTING A FEW HRS.

MODELS CONTINUE TO SHOW A GUSTIER NW FLOW DEVELOPING OVER THE AREA
DURING THE EARLIER HALF OF NEXT WEEK. VENTILATION RATES SHOULD
IMPROVE IN AREAS DUE TO THE HIGHER TRANSPORT WINDS BUT LOWER MIXING
HEIGHTS WILL PRESENT SOME OF THE AREA FROM GETTING INTO THE
FAIR/GOOD TO EXCELLENT READINGS. SUSPECT VENT RATE VALUES WILL
ADJUST SOME AS THE FLOW ADJUSTS. THE FLOW DOES LOOK TO BE DRIER WITH
TEMPERATURES BECOMING A BIT WARMER. THE GFS IS DRY BUT THE ECMWF IS
STILL SPITTING OUT LIGHTER PRECIPITATION AMOUNTS ACROSS THE EAST ON
TUESDAY. WOULD LIKE TO SEE ANOTHER DAY OR TWO WORTH OF CONSISTENT
MODEL RUNS BEFORE TOTALLY BUYING OFF ON THIS SCENARIO.

50

&&

.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR THE
FOLLOWING ZONES...NMZ501>508-510-511.

WINTER WEATHER ADVISORY FROM 8 AM THIS MORNING TO 11 PM MST THIS
EVENING FOR THE FOLLOWING ZONES...NMZ512>514.

&&

$$







AREA FORECAST DISCUSSION

NWS ALBUQUERQUE NM

 312 AM MST WED DEC 17 2014

.SYNOPSIS...
SEVERAL UPPER LEVEL DISTURBANCES TODAY AND THURSDAY WILL BRING
MUCH NEEDED PRECIPITATION TO THE LAND OF ENCHANTMENT. MUCH OF THE
PRECIPITATION WILL FAVOR WESTERN...AND PERHAPS TO SOME
EXTENT...CENTRAL NEW MEXICO. 1 TO 3 INCH SNOW AMOUNTS WILL BE
COMMON ABOVE 6000 FEET...WITH 3 TO 5 INCHES ACROSS THE HIGHER
TERRAIN. AFTER THE LAST SYSTEM EXITS THE STATE THURSDAY NIGHT...A
MUCH QUIETER FRIDAY WILL PREVAIL...BUT TEMPERATURES WILL REMAIN
CHILLY. MODELS ARE BACKING OFF ON PRECIPITATION POTENTIAL THIS
WEEKEND AND EARLY NEXT WEEK...BUT THERE IS STILL PLENTY OF TIME
FOR THAT TO CHANGE.

&&

.DISCUSSION...
AFTER MANY DIFFERENT DEPICTIONS OF TODAYS EVENT BY THE MODELS
OVER THE LAST FEW DAYS...IT APPEARS THAT THEY HAVE FINALLY COME
INTO AGREEMENT. TWO QUICK MOVING SHORTWAVE TROUGHS WILL CROSS NM
TODAY...BOTH CURRENTLY WELL DEFINED ON WATER VAPOR IMAGERY. THE
FIRST IS ASSOCIATED WITH THE LIGHTNING ACROSS NORTHERN MEXICO THIS
MORNING...WHILE THE SECOND IS ASSOCIATED WITH THE LIGHTNING OFF
THE COAST OF CALI. SHOWERS ARE ALREADY DEVELOPING AHEAD OF THE
FIRST SYSTEM IN ARIZONA AND TO SOME EXTENT WESTERN NM. THIS SYSTEM
LOOKS TO CROSS NM THIS MORNING AND EARLY THIS AFTERNOON. MOST
OPERATIONAL MODELS SHOW THE FAVORED AREA OF PRECIPITATION ACROSS
THE NW QUARTER OF NM. TEMPS ARE COLD ENOUGH FOR SOME SNOW EVEN
ACROSS THE NW PLATEAU...THUS A GOOD CALL BY THE EVENING CREW TO
ADD ZONE 501 TO THE WINTER WX ADVY. THE SECOND DISTURBANCE WILL
COME QUICKLY AFTER THE FIRST AND CROSS NM LATE THIS AFTN AND THIS
EVE. SNOW LEVELS THIS AFTN WILL RANGE FROM 5500-6000 FEET OR SO.
WHILE THE FIRST SYSTEM MAY BRING A MORE SOLID AREA OF SNOW...THE
PRECIPITATION WITH THE SECOND SYSTEM LOOKS TO BE MORE CONVECTIVE
IN NATURE...AND MAY EVEN SEE SOME ISOLATED THUNDERSTORMS THIS
AFTERNOON. AREAS ALONG AND WEST OF THE RIO GRANDE WILL GENERALLY
BE FAVORED FOR PRECIPITATION.ONE INTERESTING NOTE...HOWEVER...IS
THAT THE HRRR HAS TRENDED BACK ON PRECIPITATION OVER THE LAST
SEVERAL RUNS...AT LEAST WITH PRECIPITATION THROUGH EARLY AFTN.
WITH ALL THAT SAID...THE WINTER WX ADVYS LOOK PRETTY GOOD...THOUGH
SNOW AMOUNTS WILL CERTAINLY BE ON THE LIGHTER SIDE OF ADVISORY
CRITERIA FOR MOST AREAS.

A THIRD SHORTWAVE WILL ARRIVE ON THURSDAY...THOUGH MOST OF THE
ENERGY ASSOCIATED WITH THIS SYSTEM WILL DIVE SOUTH OF THE CWA. SOME
LIGHT SHOWERY ACTIVITY SHOULD OCCUR ACROSS THE WEST AGAIN...BUT
AMOUNTS WILL BE MINIMAL. THE SOUTHERN TIER OF THE CWA...FROM THE
SOUTHWEST MTNS TO ROOSEVELT COUNTY...WILL HAVE THE BEST CHANCES FOR
PRECIPITATION...BUT EVEN THEN...AMOUNTS WILL BE MINIMAL. COLD TEMPS
WILL KEEP SNOW LEVELS LOW...GENERALLY AOB 5500 FEET.

AFTER THE THIRD SYSTEM SLIDES EAST THURSDAY NIGHT...FRIDAY SHOULD BE
QUIET...THOUGH STILL CHILLY. MODELS ARE SHOWING A TROUGH CROSSING NM
ON SATURDAY...BUT LITTLE MOISTURE IS ASSOCIATED WITH IT SO NOT
EXPECTING PRECIP ATTM. THEREAFTER...STRONG NORTHWEST FLOW LOOKS TO
BE THE RULE. THE ECMWF IS SHOWING A DISTURBANCE WITHIN THE FLOW MAY
CLIP NE NM ON MONDAY AND MONDAY NIGHT. THIS COMBINED WITH AN
ASSOCIATED COLD FRONT MAY RESULT IN SOME LIGHT SHOWERS ACROSS THE
NORTHEAST IF THE ECMWF IS CORRECT. OTHERWISE...DRIER CONDITIONS
LOOK TO BE THE RULE THROUGH AT LEAST MID WEEK.

34

&&

.FIRE WEATHER...
MAIN FIRE WEATHER HIGHLIGHTS INCLUDE AN UNSETTLED WEATHER PATTERN
WITH SOME CHANCES OF WETTING MOISTURE ACROSS WESTERN/CENTRAL AREAS
THROUGH THURSDAY MORNING. THE WEEKEND SYSTEM JUST LOOKS TOO DRY.
GUSTIER NW WINDS AND DECENT VENTILATION IN AREAS EXPECTED SUNDAY
THROUGH EARLY NEXT WEEK.

CURRENT RADAR TRENDS SHOW SHOWER DEVELOPMENT AND SOME ORGANIZATION
IN THE PRECIPITATION FIELD OVER ARIZONA. SNOW AND LOWER ELEVATION
RAIN SHOWERS WILL SPREAD ACROSS THE WESTERN HALF OF THE AREA THROUGH
THE DAY PERIOD WITH LINGERING IMPACTS INTO THE OVERNIGHT. OROGRAPHIC
WEST FACING SLOPES LOOK TO BE FAVORED WITH THE WETTING
PRECIPITATION. EASTERN AREAS WILL SEE SCANT PRECIPITATION RESULTS.
TEMPERATURES WILL BE COOLER THAN NORMAL WITH HIGH RH VALUES FAVORING
THE WESTERN HALF. FLOW ALOFT WILL INCREASE AND WILL COMBINE WITH
RISING MIXING HEIGHTS TO PRODUCE IMPROVING VENTILATION MOST AREAS.
THE SOUTHERN HALF WILL BE THE FOCUS FOR GOOD TO EXCELLENT RATINGS.
SURFACE WINDS WILL BE BREEZY AT TIMES ACROSS THE SOUTHERN
HALF...ESPECIALLY OVER THE MOUNTAIN RIDGES/PEAKS.

A SECONDARY PACIFIC WAVE OR TROUGH WILL SLIDE OVER THE REGION ON
THURSDAY. MODELS HAVE BEEN TAKING THE MAIN PIECE OF ENERGY
ASSOCIATED WITH THE TROUGH FURTHER SOUTH SO IMPACTS TO THE FIRE WX
AREA LOOK TO BE MINIMAL AT THIS TIME. PERHAPS SOME LOCALIZED WETTING
MOISTURE ACROSS THE FAR SOUTH. EITHER WAY...HIGH TEMPERATURES WILL
REMAIN BELOW NORMAL MOST AREAS WITH HIGHER HUMIDITY READINGS. MIXING
HEIGHTS APPEAR TO BE NEAR SEASONABLE IF NOT A LITTLE HIGHER THAN
NORMAL ALTHOUGH TRANSPORT WINDS WILL LOWER COMPARED TO TODAY/S
VALUES. THUS...VENT RATES WILL LOWER. LOOKING AT A STRIP OF FAIR
CONDITIONS BETWEEN FARMINGTON TO THE ESTANCIA VALLEY BUT WOULD ONLY
BE FAIR FOR 2 TO 4 HRS MOST LOCATIONS.

AS MENTIONED ABOVE...STORM SYSTEM FOR THE WEEKEND PERIOD LOOKS TO BE
A NON EVENT. THERE WILL BE A PACIFIC WAVE CAUGHT IN NW FLOW MOVING
OVER THE AREA SATURDAY NIGHT. STRENGTHENING NW FLOW WILL BE FOUND ON
THE BACKSIDE OF THE WAVE AND PROVIDE SOME BREEZES ON SUNDAY.
ESPECIALLY IMPACTING THE MT TAYLOR TO CLINES CORNER AREA. SURFACE
WINDS ON SATURDAY APPEAR TO BE LIGHT. VENTILATION RATES ON SATURDAY
LOOK TO BE ON THE LOWER SIDE WITH SOME FAIR TO GOOD CONDITIONS
GENERALLY LASTING A FEW HRS.

MODELS CONTINUE TO SHOW A GUSTIER NW FLOW DEVELOPING OVER THE AREA
DURING THE EARLIER HALF OF NEXT WEEK. VENTILATION RATES SHOULD
IMPROVE IN AREAS DUE TO THE HIGHER TRANSPORT WINDS BUT LOWER MIXING
HEIGHTS WILL PRESENT SOME OF THE AREA FROM GETTING INTO THE
FAIR/GOOD TO EXCELLENT READINGS. SUSPECT VENT RATE VALUES WILL
ADJUST SOME AS THE FLOW ADJUSTS. THE FLOW DOES LOOK TO BE DRIER WITH
TEMPERATURES BECOMING A BIT WARMER. THE GFS IS DRY BUT THE ECMWF IS
STILL SPITTING OUT LIGHTER PRECIPITATION AMOUNTS ACROSS THE EAST ON
TUESDAY. WOULD LIKE TO SEE ANOTHER DAY OR TWO WORTH OF CONSISTENT
MODEL RUNS BEFORE TOTALLY BUYING OFF ON THIS SCENARIO.

50

&&

.AVIATION...
06Z TAF CYCLE
CIGS WILL CONTINUE TO LOWER ACROSS MOST AREAS NEAR TO WEST OF THE
CENTRAL MT CHAIN THROUGH AT LEAST THE MORN HOURS WED ALONG WITH
AREAS OF LIGHT TO OCCASIONALLY MODERATE RA AND SN. MOST OF THE
MORE SIGNIFICANT PRECIP SHOULD REMAIN NORTH OF A LINE FROM QUEMADO
TO RIO RANCHO TO SAF AND RTN. CIGS WILL LOWER TO MVFR AND
OCCASIONALLY IFR IN THIS AREA STARTING BETWEEN 10Z AND 14Z WITH A
FEW INSTANCES OF LIFR NOT OUT OF THE QUESTION IN HEAVIER SHSN. GUP
AND TO A SLIGHTLY LESSER DEGREE FMN TO BE MOST IMPACTED BY THE LOW
CIGS AND PRECIP. MARGINALLY MVFR CIGS POSS AT AEG...ABQ AND SAF
BETWEEN ABOUT 15 AND 23Z WED AND AGAIN AFTER 02Z. MVFR CIGS MAY
DEVELOP BETWEEN 11Z AND 18Z WED MORN AT ROW WITH A LOWER
CONFIDENCE OF SAME AT TCC SAME TIME PERIOD...THOUGH STILL LOOKS A
LITTLE MORE LIKELY THAT MVFR DECK WILL REMAIN EAST OR SE OF THOSE
SITES. 43

&&

.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON......................  42  26  42  20 /  70  40  20   5
DULCE...........................  37  21  37  14 /  70  50  20  20
CUBA............................  37  22  36  16 /  80  60  20  20
GALLUP..........................  39  21  39  14 /  80  40  20   5
EL MORRO........................  36  21  35  13 /  70  50  30  10
GRANTS..........................  41  22  40  13 /  60  40  20  10
QUEMADO.........................  38  23  34  22 /  60  40  30  20
GLENWOOD........................  50  31  48  28 /  50  40  40  20
CHAMA...........................  36  19  35  13 /  80  60  30  30
LOS ALAMOS......................  40  28  37  25 /  60  40  20  20
PECOS...........................  37  25  38  21 /  50  30  20  20
CERRO/QUESTA....................  34  16  33  11 /  70  40  20  20
RED RIVER.......................  30  14  31   6 /  80  50  30  30
ANGEL FIRE......................  35  11  34   3 /  70  40  20  20
TAOS............................  39  19  38  14 /  60  30  20  20
MORA............................  40  24  40  18 /  50  30  10  20
ESPANOLA........................  43  26  42  22 /  40  30  10  10
SANTA FE........................  39  27  38  25 /  60  40  20  10
SANTA FE AIRPORT................  44  23  41  21 /  50  30  10  10
ALBUQUERQUE FOOTHILLS...........  46  28  43  27 /  60  30  10  10
ALBUQUERQUE HEIGHTS.............  48  29  45  28 /  50  20  10  10
ALBUQUERQUE VALLEY..............  49  26  46  25 /  50  20  10  10
ALBUQUERQUE WEST MESA...........  47  28  45  26 /  50  20  10  10
LOS LUNAS.......................  50  22  46  21 /  50  20  10  10
RIO RANCHO......................  47  30  45  27 /  50  30  10  10
SOCORRO.........................  52  28  47  27 /  30  20  20  20
SANDIA PARK/CEDAR CREST.........  42  26  39  24 /  60  30  10  20
TIJERAS.........................  44  28  41  24 /  60  30  10  10
MORIARTY/ESTANCIA...............  44  19  42  18 /  40  30  10  10
CLINES CORNERS..................  41  24  39  20 /  50  20  10  20
GRAN QUIVIRA....................  44  27  41  25 /  40  30  10  30
CARRIZOZO.......................  47  28  45  26 /  30  20  10  40
RUIDOSO.........................  43  24  44  22 /  40  20  10  50
CAPULIN.........................  42  19  40  17 /  40  20  10  20
RATON...........................  45  20  45  16 /  40  20  10  20
SPRINGER........................  48  21  46  20 /  30  10   5  20
LAS VEGAS.......................  45  23  45  18 /  40  10   5  20
CLAYTON.........................  50  25  45  26 /  10  10   5  20
ROY.............................  48  24  46  23 /  20  10   5  20
CONCHAS.........................  54  30  50  30 /  10   5   5  20
SANTA ROSA......................  55  32  51  29 /  20   5   5  20
TUCUMCARI.......................  57  29  51  27 /  10   0   5  20
CLOVIS..........................  54  31  53  29 /  10   0   5  30
PORTALES........................  55  30  54  29 /  10   0   5  30
FORT SUMNER.....................  54  31  54  30 /  10   0   5  20
ROSWELL.........................  61  31  56  32 /   5   0   5  30
PICACHO.........................  52  31  51  30 /  20   5   5  40
ELK.............................  49  30  49  28 /  30  10  10  40

&&

.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR THE
FOLLOWING ZONES...NMZ501>508-510-511.

WINTER WEATHER ADVISORY FROM 8 AM THIS MORNING TO 11 PM MST THIS
EVENING FOR THE FOLLOWING ZONES...NMZ512>514.

&&

$$

34






AREA FORECAST DISCUSSION

NWS BURLINGTON VT

 928 PM EST THU DEC 18 2014

.SYNOPSIS...
BROAD CYCLONIC CIRCULATION SURROUNDING SLOW-MOVING LOW PRESSURE
OVER THE CANADIAN MARITIMES WILL MAINTAIN CLOUDY SKIES AND A FEW
MOUNTAIN SNOW SHOWERS TONIGHT. HIGH PRESSURE BUILDS ACROSS THE
NORTH COUNTRY FRIDAY AND THROUGH THE WEEKEND...BRINGING GENERALLY
DRY WEATHER CONDITIONS...THOUGH SKIES WILL REMAIN VARIABLY CLOUDY
OWING TO LOW STRATUS. THE NEXT SIGNIFICANT STORM SYSTEM ARRIVES
FOR CHRISTMAS EVE WITH VERY WINDY AND MILD CONDITIONS...WITH
PERIODS OF MODERATE TO BRIEFLY HEAVY RAIN. BRISK AND SOMEWHAT
COLDER CONDITIONS ARE EXPECTED FOR CHRISTMAS DAY...WITH A
TRANSITION TO SNOW SHOWERS POSSIBLE...ESPECIALLY OVER THE HIGHER
TERRAIN.

&&

.NEAR TERM /UNTIL 7 AM FRIDAY MORNING/...
AS OF 928 PM EST THURSDAY...PATCHY -FZDZ HAS MATERIALIZED ACROSS
PORTIONS OF NRN NY AND CENTRAL/NRN VT OVER THE PAST 3 HOURS AS
PRIMARY DENDRITIC SNOW GROWTH LAYERS ARE TRENDING UNSATURATED.
THIS HAS BEEN PICKED UP QUITE WELL ON THIS EVENING`S RAP SOUNDING
PROFILES AND HAVE ISSUED SPECIAL WEATHER STATEMENTS TO HIGHLIGHT
POTENTIAL LIGHT GLAZE ICING ON UNTREATED/ELEVATED SURFACES
OVERNIGHT. OTHERWISE FORECAST REMAINS IN GOOD SHAPE AS BLOCKED
MOIST NORTHWESTERLY FLOW CONTINUES ACROSS THE AREA. OTHER THAN THE
PATCHY -FZDZ AND SOME PASSING FLURRIES/LIGHT SHSN ACTIVITY
OVERNIGHT...A GENERALLY CLOUDY NIGHT IS EXPECTED AS TEMPERATURES
SETTLE INTO THE LOWER AND MID 20S BY SUNRISE FRIDAY. HAVE A GREAT
NIGHT.

&&

.SHORT TERM /7 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
AS OF 230 PM EST THURSDAY...RELATIVELY TRANQUIL SHORT-TERM
PERIOD...ONLY ISSUE WILL BE EXTENT OF STRATUS AND ASSOCIATED
IMPACT ON RADIATIVE HEATING/COOLING AND TEMPERATURES. HIGH
PRESSURE CENTERED ACROSS THE GREAT LAKES FRIDAY DRIFTS ACROSS THE
NERN CONUS AND SERN CANADA SATURDAY AND SATURDAY NIGHT. THIS WILL
BRING LIGHT WINDS...ESPECIALLY ON SATURDAY. 12Z NAM HAS TRENDED
TOWARD HIGHER LOW-LEVEL RH FOR FRIDAY. WITH WEAK WIND FIELDS AND
LOW-LEVEL INVERSION LAYER/LOW SUN ANGLE...WILL KEEP ANY PARTIAL
CLEARING FAIRLY LIMITED. SATURDAY WILL FEATURE PARTLY SUNNY
CONDITIONS...BUT AGAIN WITH AREAS OF STRATUS LIKELY HOLDING ON
ESPECIALLY CENTRAL/ERN VT. HAVE STAYED NEAR MOS CONSENSUS ON HIGH
TEMPERATURES...AND TRENDED ABOVE MOS CONSENSUS ON LOW TEMPS DUE
TO POTENTIAL CLOUDINESS DURING FRIDAY AND SATURDAY NIGHT.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 228 PM EST THURSDAY...MODEL GUIDANCE CONTINUES TO SHOW
SURFACE HIGH PRESSURE ON SUNDAY WITH SHORTWAVE ENERGY MOVING
THROUGH THE AREA, INCREASING CLOUDS ACROSS THE NORTH COUNTRY. THE
SURFACE HIGH SHIFTS NORTHEASTWARD OVER THE CANADIAN MARITIMES,
WHICH WILL PUT THE NORTH COUNTRY IN SOUTH TO SOUTHWEST FLOW,
COINCIDING WITH SOME UPPER LEVEL RIDGING. THIS WILL RESULT IN
WARMING TEMPERATURES FROM MAXES OF MID TO UPPER 20S TO END THE
WEEKEND, TO LOW TO MID 30S TO BEGIN THE WORK WEEK.

AS A LARGE DEEPENING UPPER LEVEL TROUGH STRETCHES SOUTHWARD
ACROSS THE PLAINS, EDGING INTO THE TEXARKANA REGION, A WAVE AHEAD
OF THIS MAIN TROUGH WILL INCREASE THE THREAT OF SNOW SHOWERS
TRANSITIONING RAIN SHOWERS IN THE VALLEYS AS WE RESIDE IN THE WARM
SECTOR MONDAY NIGHT INTO TUESDAY. THE THREAT FOR HEAVIER/MORE
SIGNIFICANT PRECIPITATION INCREASES WEDNESDAY INTO WEDNESDAY NIGHT
AS THE UPPER TROUGH BECOMES NEGATIVELY TILTED AND THE ASSOCIATED
SFC LOW STRENGTHENS QUICKLY. TRACK OF UPPER LEVEL FEATURES AND
SURFACE FEATURES STILL UNDER DEBATE AMONG THE MODELS, BUT STRONG
WINDS ARE ASSOCIATED WITH THIS SYSTEM ARE PRESENT IN GFS AND
ECMWF...WITH 850 MB WINDS EXCEEDING 55 KTS. GFS BEING STRONGER AND
850MB WINDS EXCEED 65KTS IN AREAS. THIS MAY BE PROBLEMATIC ACROSS
THE SUMMITS AND NWRN SLOPES. THIS WILL BE A STORM TO KEEP AN EYE
ON AS IT DEVELOPS AND TRACKS TOWARD THE NE USA.

&&

.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
THROUGH 00Z SATURDAY...PERSISTENT STRATUS DECK WILL BRING
PREDOMINANTLY MVFR CONDITIONS TO THE REGION THROUGH THE PERIOD.
WIDESPREAD MVFR CONDITIONS EXIST THIS EVENING AND WILL CONTINUE
THROUGH TONIGHT AND ON FRIDAY. PERIODS OF IFR ALSO EXPECTED AT
MPV/SLK TONIGHT AND CONTINUING AT SLK FOR FRIDAY. PBG IS THE ONLY
EXCEPTION WHERE SOME LOCAL DOWNSLOPING HAS ALLOWED CEILINGS TO
LIFT TO VFR THIS EVENING AND THAT IS ALSO EXPECTED TO CONTINUE
THROUGH FRIDAY. SOME LIGHT SNOW SHOWERS REMAIN AT
BTV/SLK/MPV...AND WILL LIKELY CONTINUE THROUGH AT LEAST
06Z...POSSIBLY LASTING TO 12Z AT MPV/SLK. HOWEVER ANY SNOW SHOWERS
WILL BE LIGHT WITH ONLY MINOR VISIBILITY REDUCTIONS EXPECTED...IF
ANY AT ALL.

NORTHWEST WINDS FROM 5 TO 10 KNOTS WILL CONTINUE THROUGH TONIGHT
AND FRIDAY...EXCEPT LOCALLY WEST/SOUTHWEST AT MSS/SLK.

OUTLOOK 00Z SATURDAY THROUGH TUESDAY...

00Z SAT-00Z SUN...IMPROVING CONDITIONS...BUT CHANCE OF LINGERING
STRATUS IN SOME AREAS BRINGING PERIODS OF MVFR.

00Z SUN-00Z TUE...VFR UNDER HIGH PRESSURE.

00Z TUE-00Z WED...PERIODS OF MVFR IN LIGHT MIXED PRECIPITATION.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.

&&

$$
SYNOPSIS...BANACOS
NEAR TERM...JMG
SHORT TERM...BANACOS
LONG TERM...KGM
AVIATION...MUCCILLI




AREA FORECAST DISCUSSION

NWS BURLINGTON VT

 645 PM EST THU DEC 18 2014

.SYNOPSIS...
BROAD CYCLONIC CIRCULATION SURROUNDING SLOW-MOVING LOW PRESSURE
OVER THE CANADIAN MARITIMES WILL MAINTAIN CLOUDY SKIES AND A FEW
MOUNTAIN SNOW SHOWERS TONIGHT. HIGH PRESSURE BUILDS ACROSS THE
NORTH COUNTRY FRIDAY AND THROUGH THE WEEKEND...BRINGING GENERALLY
DRY WEATHER CONDITIONS...THOUGH SKIES WILL REMAIN VARIABLY CLOUDY
OWING TO LOW STRATUS. THE NEXT SIGNIFICANT STORM SYSTEM ARRIVES
FOR CHRISTMAS EVE WITH VERY WINDY AND MILD CONDITIONS...WITH
PERIODS OF MODERATE TO BRIEFLY HEAVY RAIN. BRISK AND SOMEWHAT
COLDER CONDITIONS ARE EXPECTED FOR CHRISTMAS DAY...WITH A
TRANSITION TO SNOW SHOWERS POSSIBLE...ESPECIALLY OVER THE HIGHER
TERRAIN.

&&

.NEAR TERM /UNTIL 7 AM FRIDAY MORNING/...
AS OF 645 PM EST THURSDAY...FORECAST REMAINS IN GOOD SHAPE AS WE
PROGRESS INTO THE EVENING HOURS. DID OPT TO INTRODUCE SOME PATCHY
-FZDZ TO OUR NRN NY COUNTIES AND INTO FAR WRN VT THIS
EVENING/OVERNIGHT BASED OFF LATEST RAP SOUNDING PROFILES AND A
RECENT LIGHT ICING REPORT ON THE 23Z KSLK OBSERVATION. ANY ICING
WOULD BE MINIMAL AT BEST THOUGH. OTHERWISE
TEMPERATURES/WINDS/POPS/SKY COVER REMAIN LARGELY ON TRACK SO ONLY
OTHER ADJUSTMENT WAS TO BLEND CURRENT OBSERVATIONAL DATA INTO
EXISTENT DATASETS AT 06Z. PRIOR DISCUSSION FOLLOWS. HAVE A GREAT
EVENING.

PRIOR DISCUSSION FROM 230 PM EST THURSDAY...
DEEP-LAYER LIGHT TO MODERATE NWLY FLOW IN PLACE AS CLOSED LOW
SLOWLY EXITS NEWD ACROSS THE CANADIAN MARITIMES OVERNIGHT. 12Z NAM
MODEL SOUNDINGS INDICATE THAT LOW- LEVEL STRATUS LAYER WILL BE
DIFFICULT TO SCOUR OUT GIVEN PRESENCE OF 925-875MB INVERSION AND
TRAPPED MOISTURE/SATURATED LAYER BELOW THAT LEVEL. BEST CHANCE FOR
ANY PARTIAL CLEARING WILL BE WITH WEAK DOWNSLOPE FLOW INTO THE CT
RIVER VALLEY OR ALONG THE ERN SLOPES OF THE ADIRONDACKS. VISIBLE
IMAGERY ALSO INDICATES THAT CONSIDERABLE STRATUS ALSO REMAINS IN
PLACE WELL NORTH AND WEST OF THE ST. LAWRENCE VALLEY. SO, LIKELY
REMAINING CLOUDY ACROSS FAR WRN SECTIONS AS WELL. IT DOES APPEAR
BASED ON 12Z NAM AND LOCAL 12Z BTV-WRF RUNS THAT LINGERING SNOW
SHOWER ACTIVITY ACROSS THE HIGHER TERRAIN AREAS WILL GRADUALLY
WANE TONIGHT AS SOME DRYING OCCURS ABOVE THE INVERSION LAYER.
THUS...WILL INDICATE DECREASING POPS ACROSS THE MTNS
OVERNIGHT...WITH JUST A DUSTING TO 1" OF ADDITIONAL SNOW
ACCUMULATION POSSIBLE FOR THE CENTRAL AND NORTHERN GREEN
MOUNTAINS. GIVEN STRATUS DECK...WILL TREND ABOVE MOS CONSENSUS ON
OVERNIGHT LOWS. RECENT BIAS-CORRECTION SUGGESTS LOWS 3-4DEG ABOVE
12Z NAM- MOS GUIDANCE...AND WILL TREND LOWS IN THAT DIRECTION
(GENERALLY LOW-MID 20S ACROSS THE AREA).

&&

.SHORT TERM /7 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
AS OF 230 PM EST THURSDAY...RELATIVELY TRANQUIL SHORT-TERM
PERIOD...ONLY ISSUE WILL BE EXTENT OF STRATUS AND ASSOCIATED
IMPACT ON RADIATIVE HEATING/COOLING AND TEMPERATURES. HIGH
PRESSURE CENTERED ACROSS THE GREAT LAKES FRIDAY DRIFTS ACROSS THE
NERN CONUS AND SERN CANADA SATURDAY AND SATURDAY NIGHT. THIS WILL
BRING LIGHT WINDS...ESPECIALLY ON SATURDAY. 12Z NAM HAS TRENDED
TOWARD HIGHER LOW-LEVEL RH FOR FRIDAY. WITH WEAK WIND FIELDS AND
LOW-LEVEL INVERSION LAYER/LOW SUN ANGLE...WILL KEEP ANY PARTIAL
CLEARING FAIRLY LIMITED. SATURDAY WILL FEATURE PARTLY SUNNY
CONDITIONS...BUT AGAIN WITH AREAS OF STRATUS LIKELY HOLDING ON
ESPECIALLY CENTRAL/ERN VT. HAVE STAYED NEAR MOS CONSENSUS ON HIGH
TEMPERATURES...AND TRENDED ABOVE MOS CONSENSUS ON LOW TEMPS DUE
TO POTENTIAL CLOUDINESS DURING FRIDAY AND SATURDAY NIGHT.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 228 PM EST THURSDAY...MODEL GUIDANCE CONTINUES TO SHOW
SURFACE HIGH PRESSURE ON SUNDAY WITH SHORTWAVE ENERGY MOVING
THROUGH THE AREA, INCREASING CLOUDS ACROSS THE NORTH COUNTRY. THE
SURFACE HIGH SHIFTS NORTHEASTWARD OVER THE CANADIAN MARITIMES,
WHICH WILL PUT THE NORTH COUNTRY IN SOUTH TO SOUTHWEST FLOW,
COINCIDING WITH SOME UPPER LEVEL RIDGING. THIS WILL RESULT IN
WARMING TEMPERATURES FROM MAXES OF MID TO UPPER 20S TO END THE
WEEKEND, TO LOW TO MID 30S TO BEGIN THE WORK WEEK.

AS A LARGE DEEPENING UPPER LEVEL TROUGH STRETCHES SOUTHWARD
ACROSS THE PLAINS, EDGING INTO THE TEXARKANA REGION, A WAVE AHEAD
OF THIS MAIN TROUGH WILL INCREASE THE THREAT OF SNOW SHOWERS
TRANSITIONING RAIN SHOWERS IN THE VALLEYS AS WE RESIDE IN THE WARM
SECTOR MONDAY NIGHT INTO TUESDAY. THE THREAT FOR HEAVIER/MORE
SIGNIFICANT PRECIPITATION INCREASES WEDNESDAY INTO WEDNESDAY NIGHT
AS THE UPPER TROUGH BECOMES NEGATIVELY TILTED AND THE ASSOCIATED
SFC LOW STRENGTHENS QUICKLY. TRACK OF UPPER LEVEL FEATURES AND
SURFACE FEATURES STILL UNDER DEBATE AMONG THE MODELS, BUT STRONG
WINDS ARE ASSOCIATED WITH THIS SYSTEM ARE PRESENT IN GFS AND
ECMWF...WITH 850 MB WINDS EXCEEDING 55 KTS. GFS BEING STRONGER AND
850MB WINDS EXCEED 65KTS IN AREAS. THIS MAY BE PROBLEMATIC ACROSS
THE SUMMITS AND NWRN SLOPES. THIS WILL BE A STORM TO KEEP AN EYE
ON AS IT DEVELOPS AND TRACKS TOWARD THE NE USA.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
THROUGH 00Z SATURDAY...PERSISTENT STRATUS DECK WILL BRING
PREDOMINANTLY MVFR CONDITIONS TO THE REGION THROUGH THE PERIOD.
WIDESPREAD MVFR CONDITIONS EXIST THIS EVENING AND WILL CONTINUE
THROUGH TONIGHT AND ON FRIDAY. PERIODS OF IFR ALSO EXPECTED AT
MPV/SLK TONIGHT AND CONTINUING AT SLK FOR FRIDAY. PBG IS THE ONLY
EXCEPTION WHERE SOME LOCAL DOWNSLOPING HAS ALLOWED CEILINGS TO
LIFT TO VFR THIS EVENING AND THAT IS ALSO EXPECTED TO CONTINUE
THROUGH FRIDAY. SOME LIGHT SNOW SHOWERS REMAIN AT
BTV/SLK/MPV...AND WILL LIKELY CONTINUE THROUGH AT LEAST
06Z...POSSIBLY LASTING TO 12Z AT MPV/SLK. HOWEVER ANY SNOW SHOWERS
WILL BE LIGHT WITH ONLY MINOR VISIBILITY REDUCTIONS EXPECTED...IF
ANY AT ALL.

NORTHWEST WINDS FROM 5 TO 10 KNOTS WILL CONTINUE THROUGH TONIGHT
AND FRIDAY...EXCEPT LOCALLY WEST/SOUTHWEST AT MSS/SLK.

OUTLOOK 00Z SATURDAY THROUGH TUESDAY...

00Z SAT-00Z SUN...IMPROVING CONDITIONS...BUT CHANCE OF LINGERING
STRATUS IN SOME AREAS BRINGING PERIODS OF MVFR.

00Z SUN-00Z TUE...VFR UNDER HIGH PRESSURE.

00Z TUE-00Z WED...PERIODS OF MVFR IN LIGHT MIXED PRECIPITATION.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.

&&

$$
SYNOPSIS...BANACOS
NEAR TERM...JMG/BANACOS
SHORT TERM...BANACOS
LONG TERM...KGM
AVIATION...MUCCILLI




AREA FORECAST DISCUSSION

NWS BINGHAMTON NY

 445 PM EST WED DEC 17 2014

.SYNOPSIS...
AN UPPER LEVEL STORM SYSTEM MOVING FROM THE GREAT LAKES TO NEW
ENGLAND WILL RESULT IN RAIN SHOWERS CHANGING TO SNOW SHOWERS
ACROSS NEW YORK STATE LATE TODAY WITH SCATTERED SNOW SHOWERS
CONTINUING TONIGHT INTO THURSDAY. FARTHER SOUTH A FEW SPRINKLES
AND FLURRIES CAN BE EXPECTED IN NORTHEAST PENNSYLVANIA. CLOUDS AND
SEASONABLY COLD TEMPERATURES WILL PERSIST FRIDAY INTO THE WEEKEND
WITH SCATTERED SNOW SHOWERS GRADUALLY DIMINISHING.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
A BAND OF STEADY LIGHT RAIN IS MOVING EAST ACROSS CENTRAL NY THIS
AFTERNOON WITH A CHANGE-OVER TO LIGHT SNOW ALREADY OCCURRING OVER
THE HIGHER ELEVATIONS AS OF 3 PM. THIS BAND WILL LIFT EAST-
NORTHEAST TOWARD THE CATSKILLS AND MOHAWK VALLEY THROUGH LATE THIS
AFTERNOON WITH LOWER ELEVATIONS GRADUALLY MIXING WITH OR CHANGING
TO LIGHT SNOW AS COLDER AIR FILTERS IN FROM THE WEST. MEANWHILE...
MAINLY DRY WEATHER CAN BE EXPECTED TO CONTINUE IN THE WILKES-BARRE
AND SCRANTON AREAS AND POINTS SOUTH WITH PRECIPTIATION REMAINING
TO THE NORTH.

PRECIPITATION SHOULD BECOME SPOTTIER AND LIGHTER EARLY THIS
EVENING IN MANY AREAS... THEN UPPER LEVEL LOW PRESSURE CURRENTLY
OVER WESTERN MICHIGAN WILL TRACK RAPIDLY EAST ACROSS THE AREA
LATER TONIGHT. THIS COULD RESULT IN A PERIOD OF ENHANCED SNOW
SHOWERS AGAIN LATE TONIGHT INTO EARLY THURSDAY MORNING. A BIT OF
LAKE ENHNACEMENT COULD ALSO OCCUR SOUTHEAST OF LAKE ONTARIO LATE
TONIGHT AS 850 MB TEMPERATURES FALL TO AROUND -8 C. LATEST HIGH
RESOLUTION NAM AND HRRR BOTH SUPPORT THE IDEA THAT SNOW SHOWERS
MAY INCREASE IN COVERAGE LATE TONIGHT WITH THE PASSAGE OF THIS
SYSTEM. BASED ON THIS HAVE UPPED POPS INTO THE LIKELY CATEGORY
LATER TONIGHT AND HAVE UP TO AN INCH OF SNOW POSSIBLE ESPECIALLY
AT HIGHER ELEVATIONS.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
UPPER LEVEL AND SURFACE LOW PRESSURE WILL TRACK SLOWLY EAST ACROSS
THE SOUTHERN CANADIAN MARITIMES THURSDAY THROUGH FRIDAY. FLOW
ACROSS OUR AREA IN THE WAKE OF THIS SYSTEM WILL BE NORTHWESTERLY WITH
PLENTY OF LOW-LEVEL MOISTURE AND 850 MB TEMPERATURES HOLDING
AROUND -8 TO -10 C... WHICH WILL BE JUST COLD ENOUGH FOR A MINOR
LAKE RESPONSE IN THE NORTHWEST FLOW. HOWEVER MOISTURE WILL BECOME
INCREASINGLY SHALLOW WITH CONSIDERABLE DRYING IN THE -10 TO -20
DEGREE SNOW GROWTH ZONE BY THURSDAY AFTERNOON. BASED ON THIS
EXPECT JUST SCATTERED LIGHT SNOW SHOWERS THURSDAY AFTERNOON INTO
FRIDAY WITH ONLY MINIMAL ACCUMULATIONS. SOME FREEZING DRIZZLE
MIGHT EVEN OCCUR THURSDAY NIGHT ALTHOUGH AT THIS POINT I THINK
THAT IS A LOW PROBABILITY SCENARIO AND I HAVE NOT INCLUDED ZL IN
THE GRIDDED FORECAST. AT THIS POINT IT APPEARS THAT CLOUDS WILL
PERSIST THROUGH FRIDAY. WITH PLENTY OF CLOUDS WE ARE NOT EXPECTING
MUCH DIURNAL VARIATION IN TEMPERATURES THROUGH FRIDAY WITH HIGHS
MAINLY 30 TO 35 AND LOWS 20 TO 25 IN MOST PLACES.

BEST CHANCE TO SEE ANY SUNSHINE MIGHT BE EARLY SATURDAY BEFORE
CLOUDS AHEAD OF THE NEXT SYSTEM STREAM NORTHEAST ACROSS THE AREA
DURNIG THE AFTERNOON. SATURDAY SHOULD BE DRY WITH TEMPERATURES
AGAIN MAINLY IN THE 30S.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
1 PM UPDATE..

FOLLOWED WPC GUIDANCE FOR THE MOST PART. SAT NGT AND SUN SOME
LIGHT SNOW WITH AN INVERTED TROF FROM A COASTAL STORM WELL OUT TO
SEA. SNOW ACCUMULATIONS WILL BE MOSTLY 2 INCHES OR LESS.

DRY SUN NGT AND MON WITH A MILD SFC HIGH. MON NGT AND TUE MODELS
NOW TRYING TO BRING A WEAK COASTAL STORM NE INTO THE AREA WITH
MIXED PRECIP. ADDED SOME LOW CHC POPS.

WED A STRONG OCCLUDED FRONT LIFTS NE AHEAD OF A LARGE BOMBING
STACKED LOW IN THE MIDWEST. WARM AIR SO PRECIP MOSTLY RAIN. THIS
WILL NEED TO BE WATCHED FIRST FOR RAIN AMOUNTS AND POSSIBLY
FLOODING AND SECOND FOR STRONG GUSTY WINDS.

ON THE TAIL END OF THE STEADY RAIN IT WILL CHANGE OVER TO SNOW WED
NGT AND STAY COLD THE REST OF THE WEEK WITH WRAP AROUND SNOW.

&&

.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
1230 PM UPDATE...

MAINLY MVFR CIGS AND VFR VSBYS NEXT 24 HOURS.

CAA WITH NW FLOW SETTING UP CHANGING RAIN SHOWERS TO SNOW. GETTING
ON THE BACK SIDE OF AN UPPER LEVEL LOW WHILE THE SFC LOW IS WELL
NE NEAR OTTAWA. PRECIP STILL IN NY BUT LIFTING NORTH SO THAT ONLY
SYR AND RME WILL HAVE SNOW SHOWERS AND FLURRIES TONIGHT. THIS WILL
KEEP CIGS MVFR AND POSSIBLY VSBY IN HEAVIER SNOW SHOWERS.

ELM WILL FALL TO MVFR CIGS AND BE MAINLY DRY. IMPROVEMENT THU MORN
TO VFR. BGM NOW HAS IFR CIGS BUT THAT SHOULD LIFT TO LOW MVFR LATE
TODAY AS THE STEADIER PRECIP LIFTS NORTH. ITH LOW MVFR NOW AND
TONIGHT. ITH AND BGM IMPROVE TO HIGHER MVFR THU MORN.

AVP SHOULD BE MOSTLY VFR AND DRY.

WEST WINDS AT 10 KTS WITH SOME SPORADIC GUSTS THIS AFTN. W TO NW
WINDS TONIGHT AT 10 KTS THEN THU 10 TO 15 KTS WITH HIGHER GUSTS.

OUTLOOK...

THUR AFTN TO FRI... MAINLY VFR. MVFR/IFR RESTRICTIONS ARE PSBL AT
KRME/KSYR/KITH/KBGM DUE TO CIGS AND AT TIMES WITH -SHSN.

FRI NGT TO SAT...VFR.

SAT NGT AND SUN...MVFR/IFR IN LIGHT SNOW.

SUN NGT AND MON...VFR/MVFR.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.

&&

$$
SYNOPSIS...MSE
NEAR TERM...MSE
SHORT TERM...MSE
LONG TERM...TAC
AVIATION...TAC






AREA FORECAST DISCUSSION

NWS BINGHAMTON NY

 315 PM EST WED DEC 17 2014

.SYNOPSIS...
AN UPPER LEVEL STORM SYSTEM MOVING FROM THE GREAT LAKES TO NEW
ENGLAND WILL RESULT IN RAIN SHOWERS CHANGING TO SNOW SHOWERS
ACROSS NEW YORK STATE LATE TODAY WITH SCATTERED SNOW SHOWERS
CONTINUING TONIGHT INTO THURSDAY. FARTHER SOUTH A FEW SPRINKLES
AND FLURRIES CAN BE EXPECTED IN NORTHEAST PENNSYLVANIA. CLOUDS AND
SEASONABLY COLD TEMPERATURES WILL PERSIST FRIDAY INTO THE WEEKEND
WITH SCATTERED SNOW SHOWERS GRADUALLY DIMINISHING.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY/...
A BAND OF STEADY LIGHT RAIN IS MOVING EAST ACROSS CENTRAL NY THIS
AFTERNOON WITH A CHANGE-OVER TO LIGHT SNOW ALREADY OCCURRING OVER
THE HIGHER ELEVATIONS AS OF 3 PM. THIS BAND WILL LIFT EAST-
NORTHEAST TOWARD THE CATSKILLS AND MOHAWK VALLEY THROUGH LATE THIS
AFTERNOON WITH LOWER ELEVATIONS GRADUALLY MIXING WITH OR CHANGING
TO LIGHT SNOW AS COLDER AIR FILTERS IN FROM THE WEST. MEANWHILE...
MAINLY DRY WEATHER CAN BE EXPECTED TO CONTINUE IN THE WILKES-BARRE
AND SCRANTON AREAS AND POINTS SOUTH WITH PRECIPTIATION REMAINING
TO THE NORTH.

PRECIPITATION SHOULD BECOME SPOTTIER AND LIGHTER EARLY THIS
EVENING IN MANY AREAS... THEN UPPER LEVEL LOW PRESSURE CURRENTLY
OVER WESTERN MICHIGAN WILL TRACK RAPIDLY EAST ACROSS THE AREA
LATER TONIGHT. THIS COULD RESULT IN A PERIOD OF ENHANCED SNOW
SHOWERS AGAIN LATE TONIGHT INTO EARLY THURSDAY MORNING. A BIT OF
LAKE ENHNACEMENT COULD ALSO OCCUR SOUTHEAST OF LAKE ONTARIO LATE
TONIGHT AS 850 MB TEMPERATURES FALL TO AROUND -8 C. LATEST HIGH
RESOLUTION NAM AND HRRR BOTH SUPPORT THE IDEA THAT SNOW SHOWERS
MAY INCREASE IN COVERAGE LATE TONIGHT WITH THE PASSAGE OF THIS
SYSTEM. BASED ON THIS HAVE UPPED POPS INTO THE LIKELY CATEGORY
LATER TONIGHT AND HAVE UP TO AN INCH OF SNOW POSSIBLE ESPECIALLY
AT HIGHER ELEVATIONS.


&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
UPPER LEVEL AND SURFACE LOW PRESSURE WILL TRACK SLOWLY EAST ACROSS
THE SOUTHERN CANADIAN MARITIMES THURSDAY THROUGH FRIDAY. FLOW
ACROSS OUR AREA IN THE WAKE OF THIS SYSTEM WILL BE NORTHWESTERLY WITH
PLENTY OF LOW-LEVEL MOISTURE AND 850 MB TEMPERATURES HOLDING
AROUND -8 TO -10 C... WHICH WILL BE JUST COLD ENOUGH FOR A MINOR
LAKE RESPONSE IN THE NORTHWEST FLOW. HOWEVER MOISTURE WILL BECOME
INCREASINGLY SHALLOW WITH CONSIDERABLE DRYING IN THE -10 TO -20
DEGREE SNOW GROWTH ZONE BY THURSDAY AFTERNOON. BASED ON THIS
EXPECT JUST SCATTERED LIGHT SNOW SHOWERS THURSDAY AFTERNOON INTO
FRIDAY WITH ONLY MINIMAL ACCUMULATIONS. SOME FREEZING DRIZZLE
MIGHT EVEN OCCUR THURSDAY NIGHT ALTHOUGH AT THIS POINT I THINK
THAT IS A LOW PROBABILITY SCENARIO AND I HAVE NOT INCLUDED ZL IN
THE GRIDDED FORECAST. AT THIS POINT IT APPEARS THAT CLOUDS WILL
PERSIST THROUGH FRIDAY. WITH PLENTY OF CLOUDS WE ARE NOT EXPECTING
MUCH DIURNAL VARIATION IN TEMPERATURES THROUGH FRIDAY WITH HIGHS
MAINLY 30 TO 35 AND LOWS 20 TO 25 IN MOST PLACES.

BEST CHANCE TO SEE ANY SUNSHINE MIGHT BE EARLY SATURDAY BEFORE
CLOUDS AHEAD OF THE NEXT SYSTEM STREAM NORTHEAST ACROSS THE AREA
DURNIG THE AFTERNOON. SATURDAY SHOULD BE DRY WITH TEMPERATURES
AGAIN MAINLY IN THE 30S.


&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
1 PM UPDATE..

FOLLOWED WPC GUIDANCE FOR THE MOST PART. SAT NGT AND SUN SOME
LIGHT SNOW WITH AN INVERTED TROF FROM A COASTAL STORM WELL OUT TO
SEA. SNOW ACCUMULATIONS WILL BE MOSTLY 2 INCHES OR LESS.

DRY SUN NGT AND MON WITH A MILD SFC HIGH. MON NGT AND TUE MODELS
NOW TRYING TO BRING A WEAK COASTAL STORM NE INTO THE AREA WITH
MIXED PRECIP. ADDED SOME LOW CHC POPS.

WED A STRONG OCCLUDED FRONT LIFTS NE AHEAD OF A LARGE BOMBING
STACKED LOW IN THE MIDWEST. WARM AIR SO PRECIP MOSTLY RAIN. THIS
WILL NEED TO BE WATCHED FIRST FOR RAIN AMOUNTS AND POSSIBLY
FLOODING AND SECOND FOR STRONG GUSTY WINDS.

ON THE TAIL END OF THE STEADY RAIN IT WILL CHANGE OVER TO SNOW WED
NGT AND STAY COLD THE REST OF THE WEEK WITH WRAP AROUND SNOW.

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
1230 PM UPDATE...

MAINLY MVFR CIGS AND VFR VSBYS NEXT 24 HOURS.

CAA WITH NW FLOW SETTING UP CHANGING RAIN SHOWERS TO SNOW. GETTING
ON THE BACK SIDE OF AN UPPER LEVEL LOW WHILE THE SFC LOW IS WELL
NE NEAR OTTAWA. PRECIP STILL IN NY BUT LIFTING NORTH SO THAT ONLY
SYR AND RME WILL HAVE SNOW SHOWERS AND FLURRIES TONIGHT. THIS WILL
KEEP CIGS MVFR AND POSSIBLY VSBY IN HEAVIER SNOW SHOWERS.

ELM WILL FALL TO MVFR CIGS AND BE MAINLY DRY. IMPROVEMENT THU MORN
TO VFR. BGM NOW HAS IFR CIGS BUT THAT SHOULD LIFT TO LOW MVFR LATE
TODAY AS THE STEADIER PRECIP LIFTS NORTH. ITH LOW MVFR NOW AND
TONIGHT. ITH AND BGM IMPROVE TO HIGHER MVFR THU MORN.

AVP SHOULD BE MOSTLY VFR AND DRY.

WEST WINDS AT 10 KTS WITH SOME SPORADIC GUSTS THIS AFTN. W TO NW
WINDS TONIGHT AT 10 KTS THEN THU 10 TO 15 KTS WITH HIGHER GUSTS.

OUTLOOK...

THUR AFTN TO FRI... MAINLY VFR. MVFR/IFR RESTRICTIONS ARE PSBL AT
KRME/KSYR/KITH/KBGM DUE TO CIGS AND AT TIMES WITH -SHSN.

FRI NGT TO SAT...VFR.

SAT NGT AND SUN...MVFR/IFR IN LIGHT SNOW.

SUN NGT AND MON...VFR/MVFR.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.

&&

$$
SYNOPSIS...MSE
NEAR TERM...MSE
SHORT TERM...MSE
LONG TERM...TAC
AVIATION...TAC






AREA FORECAST DISCUSSION

NWS BINGHAMTON NY

 1027 AM EST WED DEC 17 2014

.SYNOPSIS...
A WESTERLY FLOW OF MOIST AND SEASONABLY CHILLY AIR WILL BRING
SCATTERED RAIN SHOWERS WHICH WILL MIX WITH SNOW SHOWERS LATE
TODAY. SCATTERED SNOW SHOWERS AND FLURRIES WILL CONTINUE THROUGH
THURSDAY NIGHT WITH LIGHT SNOW ACCUMULATIONS LIKELY IN THE HIGHER
TERRAIN BETWEEN BINGHAMTON AND SYRACUSE.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED AT 1015 AM... HAVE UPDATED THE FORECAST TO INCREASE POPS
ACROSS CENTRAL NY AND FAR NORTHERN PA INTO THIS AFTERNOON AS
LATEST RADAR INDICATES THAT LIGHT RAIN SHOWERS ARE WIDESPREAD
ACROSS THE AREA LATE THIS MORNING. TEMPERATURES HAVE BEEN HOLDING
STEADY FROM THE MID 30S TO LOWER 40S AND PRECIPITATION TYPE IN OUR
AREA HAS BEEN ALL RAIN THIS MORNING. OBSERVATIONS TO THE WEST INDICATE A
CHANGE-OVER TO LIGHT SNOW AT OLE/ELZ AND BFD IN SW NY / NW PA AND
THIS TREND WILL GRADUALLY SPREAD EAST THROUGH THIS AFTERNOON WITH
SOME HIGHER ELEVATIONS IN STEUBEN COUNTY PROBABLY SEEING SNOW BY
NOON. FALLING TEMPERATURES INDICATED BY LATEST RAP FORECAST
THERMAL PROFILES SHOULD ALLOW RAIN SHOWERS TO TRANSITION TO LIGHT
SNOW SHOWERS IN MANY AREAS BY EVENING. ACCUMULATIONS THROUGH THE
DAYTIME HOURS TODAY WILL BE LITTLE TO NONE AS PRECIPITATION WILL
BE LIGHT AND SURFACE TEMPERATURES WILL REMAIN JUST ABOVE FREEZING.
PREVIOUS FORECAST IS BELOW.

AT 430 AM LOCAL RADARS SHOWED SCATTERED LIGHT RAIN SHOWERS ACROSS
WESTERN AND CENTRAL NEW YORK. TEMPERATURES RANGED FROM THE UPPER
30S TO LOWERS 40S.

SFC LOW PRES JUST NORTH OF LAKE ONTARIO WILL TRACK ALONG THE SAINT
LAWRENCE VALLEY AND WEAKEN AS A SECONDARY LOW ALONG COASTAL NEW
ENGLAND TRACKS ALONG THE COAST AND GRADUALLY INTENSIFIES. AN
ELONGATED UPPER LEVEL LOW OVER THE UPPER GREAT LAKES WILL MOVE
EAST TO THE VCNTY BY LATE TODAY. A MOIST WESTERLY FLOW WILL RESIDE
OVER THE REGION TODAY ALONG WITH WEAK COLD AIR ADVECTION.
SCATTERED RAIN SHOWERS WILL CONTINUE WHICH WILL GRADUALLY MIX WITH
SNOW SHOWERS LATER THIS AFTERNOON AS THE BOUNDARY LAYER COOLS.
THIS AFTERNOON AS REGION RESIDES ON THE BACK SIDE OF SFC FEATURES
WITH UPPER LEVEL LOW IN THE VCNTY, DEEP SYNOPTIC MOISTURE ALONG
WITH INSTABILITY WILL LEAD TO GREATER AREAL COVERAGE OF SHOWERY
ACTIVITY. BY AFTERNOON WILL INCREASE POPS TO LIKELY ACROSS THE NRN
CWA WITH HIGH CHC REST OF CENTRAL NY AND JUST SLIGHT CHC FAR SE.

MAX TEMPS WILL OCCUR LATER THIS MORNING THEN SLOWLY FALL DURING THE
AFTERNOON HOURS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
TONIGHT THROUGH THURSDAY NIGHT, UPPER LEVEL LOW WILL TRACK FROM
NYS TO NOVA SCOTIA WITH SYSTEM VERTICALLY STACKED BY THURSDAY
AFTERNOON. THESE FEATURES WILL KEEP A COOL AND MOIST NORTHWEST
FLOW ACROSS THE REGION WITH A CONTINUATION OF SCATTERED SNOW
SHOWERS AND FLURRIES. T85 NEVER DROPS ENOUGH FOR A SIGNIFICANT
CONTRIBUTION FORM LAKE ONTARIO ALTHOUGH SOME LAKE ENHANCEMENT IS
LIKELY SOUTHWEST OF LAKE ONTARIO PRIMARILY LATE TONIGHT AND
THURSDAY. THE HIGHER ELEVATIONS ACROSS ONONDAGA, ONEIDA, MADISON,
CORTLAND AND CHENANGO COUNTIES COULD SEE AROUND 2 INCHES. BY
THURSDAY NIGHT THE DEEP SYNOPTIC MOISTURE DECREASES ALONG WITH A
LOWERING INVERSION THEREFORE THE AREAL COVERAGE AND THREAT FOR
ACCUMULATING SNOW WILL DIMINISH.

LOWS TONIGHT WILL RANGE IN THE MID 20S TO LOWER 30S WITH MAXES
ON THURSDAY IN THE LOWER TO MIDDLE 30S. LOWS THURSDAY NIGHT IN THE
20S.

FRIDAY/FRIDAY NIGHT, SFC HIGH PRES WILL BUILD EAST FROM THE UPPER
GREAT LAKES BUT MODEL SOUNDINGS SHOW LOW LEVEL MOISTURE TRAPPED
UNDER A SUBSIDENCE. CONDITIONS WILL BE MAINLY DRY BUT SKIES WILL
MOST LIKELY REMAIN MOSTLY CLOUDY WITH IMPROVEMENT TO PARTY CLOUDY
FRIDAY NIGHT. HIGH FRIDAY WILL RANGE FROM THE UPPER 20S TO MID 30S.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
330 AM UPDATE..
NORTHERN STREAM WAVE BRINGS A PERIOD OF LIGHT SNOW TO THE AREA
SATURDAY NIGHT INTO SUNDAY. BOTH THE GFS AND EURO STILL KEEP THE
COASTAL SYSTEM WELL OFF THE COAST THROUGH SUNDAY NIGHT, TO HAVE
ANY IMPACT ON OUR AREA. FOLLOWED WPC GUIDANCE MONDAY BY KEEPING
OUR AREA DRY. BOTH THE GFS AND EURO HINT AT SOME MOISTURE MOVING
UP THE COAST DURING THIS TIME SO THIS WILL HAVE TO BE WATCHED.

NEXT SYSTEM WILL BE A WARM ONE, WITH THE INITIAL TRACK TO OUR
WEST THROUGH THE OHIO VALLEY. WE WILL BE WARM ENOUGH FOR RAIN
TUESDAY THROUGH CHRISTMAS EVE DAY. EVENTUALLY ENOUGH COLD AIR
ADVECTS INTO THE AREA ON A SOUTHWEST FLOW THAT WE MAY MIX WITH OR
CHANGE TO SNOW VERY LATE CHRISTMAS EVE. PLENTY OF TIME TO WATCH
THIS ONE PLAY OUT.

&&

.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
MVFR CIGS THROUGH THE END OF THE TAF PERIOD, WITH MVFR VSBYS
POSSIBLE TODAY IN SHOWERS.

DENSE FOG HAS LIFTED ACROSS THE TERMINALS AND WITH IT, THE HIGHER
THREAT FOR IFR CIGS. AT KBGM SOME IFR STILL CAN`T BE RULED OUT
THROUGH 13Z IN LIGHT FOG, BUT NOT THE 1/4 SM FOG WE HAVE HAD
RECENTLY. BEST SHOT AT SHOWERS TODAY WILL COME THIS AFTERNOON. AS
TEMPERATURES COOL A GRADUAL TRANSITION TO LIGHT SNOW IS POSSIBLE
AFTER 21Z. FOR NOW DUE TO THE EXPECTED SCATTERED NATURE OF THE
SNOW, I KEPT VSBYS IN MVFR. IF SNOW DOES MATERIALIZE, BRIEF PERIODS
OF IFR VSBSY ARE POSSIBLE THIS EVENING AND TONIGHT ESPECIALLY
NORTHERN NY TERMINALS.

WINDS TODAY VEERING INTO THE WEST-SOUTHWEST LATE THIS MORNING, AND
WEST NORTHWEST THIS AFTERNOON. SPEEDS 5 TO 10 KTS, BUT INCREASING
TO 10-15 BY LATE MORNING. WEST NORTHWEST WINDS TONIGHT AROUND 10
KTS.


OUTLOOK...

THUR TO FRI... MAINLY VFR. MVFR/IFR RESTRICTIONS ARE PSBL AT
KRME/KSYR/KITH/KBGM DUE TO CIGS AND AT TIMES WITH -SHSN.

FRI NGT TO SAT...VFR.

SAT NGT AND SUN...MVFR/IFR IN LIGHT SNOW.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.

&&

$$
SYNOPSIS...RRM
NEAR TERM...MSE/RRM
SHORT TERM...RRM
LONG TERM...HEDEN
AVIATION...HEDEN






AREA FORECAST DISCUSSION

NWS WILMINGTON NC

 1230 AM EST WED DEC 17 2014

.SYNOPSIS...
SHOWERS WILL MOVE OFFSHORE TONIGHT AS A COLD FRONT CROSSES THE
COAST. SEASONABLY COOL AND FAIR WEATHER WILL FOLLOW WEDNESDAY
THROUGH FRIDAY. AN APPROACHING STORM SYSTEM COULD BRING WET
WEATHER DURING THE UPCOMING WEEKEND. A DRYING TREND IS EXPECTED
EARLY NEXT WEEK WITH SEASONABLE TEMPERATURES...AS HIGH PRESSURE
FROM THE UPPER MID-WEST DROPS SOUTHEAST INTO THE CAROLINAS.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 920 PM TUESDAY...THIS HAS BEEN THE LITTLE LINE OF SHOWERS THAT
COULD!  EVEN THE HRRR HAS NOT SHOWN THE INCREDIBLY SOLID LINE OF
SHALLOW CONVECTION WE HAVE MOVING EAST ACROSS THE AREA. RAINFALL
AMOUNTS HAVE BEEN LIGHT...GENERALLY UNDER A TENTH OF AN INCH. THE
LUMBERTON ASOS REPORTED 0.11 AND THE LUMBERTON MESONET STATION HAD
0.14, THE TWO HIGHEST GAUGE TOTALS AVAILABLE TO US. RADAR ESTIMATES
ARE UPWARDS OF HALF AN INCH ACROSS NORTHERN ROBESON COUNTY NEAR THE
CUMBERLAND COUNTY LINE. CONVECTIVE ACTIVITY SHOULD CONTINUE TO
ADVECT EASTWARD AND OFF THE COAST BY MIDNIGHT. IN ITS WAKE CLEAR
SKIES ARE STILL EXPECTED. PREVIOUS DISCUSSION FROM 645 PM FOLLOWS...

THE FIRST WAVE OF PREFRONTAL SHOWERS AND SPRINKLES HAVE DIMINISHED
AND/OR MOVED EAST OF THE AREA. HOWEVER RADAR COMPOSITES SHOW A
NARROW BAND OF SHOWERS DEVELOPING ALONG THE FRONT ITSELF...CURRENTLY
ACROSS FAYETTEVILLE, LAURINBURG AND BENNETTSVILLE. ENVIRONMENTAL
LAPSE RATES BETWEEN 850 AND 600 MB ARE ACTUALLY QUITE STEEP (NEAR
6.5 DEG/KM OR MOIST-ADIABATIC) AND THIS ACTIVITY IS CONVECTIVE IN
NATURE WITH RADAR REFLECTIVITY IMPLYING THERE MAY BE A FEW MINUTES
OF QUITE HEAVY RAINFALL. SPC AUTOMATED MESOANALYSIS IS SHOWING
ELEVATED CAPE AROUND 100 J/KG AHEAD OF THE FRONT. MOISTURE IS A
LIMITING FACTOR WITH DEWPOINTS GENERALLY IN THE 50S WITH LIMITED
ATLANTIC INFLOW AND VIRTUALLY NO MOISTURE FROM THE GULF OF MEXICO.

LATEST HRRR MODEL RUNS INDICATE SCATTERED SHOWERS MAINLY ACROSS SE
NORTH CAROLINA CONTINUING FOR THE NEXT 2-3 HOURS...THEN SHIFTING
OFFSHORE. ACTIVITY WILL BE MORE SPARSE OR ENTIRELY ABSENT ACROSS NE
SOUTH CAROLINA AS THE BEST SYNOPTIC/UPPER LEVEL FORCING REMAINS
NORTH. NO CHANGES HAVE BEEN MADE TO FORECAST LOW TEMPS...AROUND 40
INLAND WITH MID 40S ON THE NC BEACHES.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/...
AS OF 345 PM TUESDAY...FAIR AND DRY WED/THU. SUBSIDENCE
OVERWHELMS THE COLUMN ENSURING A DEEP LAYER OF LOW RH AND WEST
WIND FLOW IN MID/UPPER ALTITUDES. PACIFIC ORIGIN SYSTEM AND
GENERAL WEST TO EAST FLOW RESULTING IN ONLY WEAK COOL AIR
ADVECTION AND MAXIMUMS WED LOOK TO REBOUND A FEW DEGREES ABOVE
NORMAL FOR MID DECEMBER. A SECONDARY BUT WEAK HIGH PRESSURE SURGE
MAY RESULT IN MAXIMUMS A DEGREE OR TWO COOLER THU...WITH
MORE/INCREASING CIRRUS THURSDAY.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 345 PM TUESDAY...LOW CONFIDENCE SPLIT FLOW FORECAST EARLY IN
THE  PERIOD. SURFACE HIGH PRESSURE TO BE COVERING A LARGE PAR OF
THE NORTHEAST AND MID ATLANTIC ON FRIDAY. SOUTHERN BRANCH FEATURE
WILL MEANWHILE BE SKIRTING THE GULF COAST. A SURPRISINGLY SLOW
MOVER GIVEN THE FAIRLY ZONAL FLOW, THIS FEATURE WILL AFFECT THE
AREA MOST ON SATURDAY. MODEL AGREEMENT APPEARS TO BE A LITTLE
BETTER IN KEEPING THE SYSTEM TO OUR SOUTH IMPLYING THAT THIS WILL
BE A LIGHT TO PERHAPS MODERATE OVERRUNNING EVENT LOCALLY. RAIN MAY
LAST INTO EARLY SUNDAY BUT AS THE SYSTEM EXITS TO THE NORTHEAST
(WHETHER OR NOT IN A STRENGTHENING STATE) SOME DRY AIR WILL PUSH
INTO THE AREA FROM THE NW. THIS NEW AREA OF HIGH PRESSURE WILL
REMAIN TO OUR NORTHWEST FOR THE REMAINDER OF THE PERIOD WHILE THE
FLOW ALOFT REMAINS WEAKLY SPLIT. EARLY IN THE PERIOD DAYTIME HIGHS
WILL BE A BIT SUPPRESSED BY CLOUDS AND/OR RAIN WHILE NIGHTTIME
LOWS REMAIN SLIGHTLY ELEVATED ABOVE CLIMO FOR THE SAME REASON.
WITH THE ARRIVAL OF THE COOLER DRY AIR DAYTIME HIGHS MAY TAKE A
SMALL HIT WHILE NIGHTTIME LOWS LOSE THE BENEFIT OF CLOUDS AND
RETURN TO NORMAL OR CLOSE TO IT.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 06Z...THE COLD FRONT IS FINALLY OFFSHORE...AND IS MOVING
FURTHER AWAY FROM THE MAINLAND EARLY THIS AM. THE INFLUX OF LOWER
DEWPOINTS...AKA DRIER AIR...IS SLOW TO ADVANCE ACROSS THE FA. AS A
RESULT...ENUF SFC BASED MOISTURE WILL BE AVBL FOR MVFR/IFR BR
DEVELOPMENT...WITH ISOLATED LIFR FROM FG. ALL TERMINALS WILL
BECOME VFR BY DAYBREAK WED AS THOSE LOWER DEWPOINTS INFILTRATE THE
FA.

EXPECT CONTINUED VFR CONDITIONS FOR THE REMAINDER OF THE 06Z TAF
ISSUANCE PERIOD. POST COLD FRONTAL WINDS WILL BECOME WNW TO NNW
AT 4-8 KT. BY SUNSET WED...WINDS WILL LIKELY DECOUPLE AS A SFC
BASED INVERSION DEVELOPS.

EXTENDED OUTLOOK...VFR THU THROUGH FRIDAY. GOOD CHANCE OF RAIN ON
SATURDAY AND SUNDAY WITH POSSIBLE MVFR/IFR CONDITIONS.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 920 PM TUESDAY...WINDS ARE AT THEIR STRONGEST ACROSS THE
COASTAL WATERS CURRENTLY, AROUND 20 KNOTS, AND SHOULD DIMINISH AS
THE FRONT CROSSES OFFSHORE. AT 9 PM THE FRONT EXTENDS FROM WESTERN
PENDER COUNTY ACROSS WHITEVILLE TO WESTERN HORRY COUNTY, MOVING EAST
AT 25 KNOTS. THE BIGGEST CHANGE WITH THIS UPDATE WAS TO INCREASE
SHOWER CHANCES ACROSS THE NC COASTAL WATERS BASED ON UPSTREAM RADAR
IMAGERY AND MESOANALYSIS CONTINUING TO SHOW SMALL BUT POSITIVE
INSTABILITY ALOFT. PREVIOUS DISCUSSION FROM 645 PM FOLLOWS...

WINDS ARE A SOLID 20 KNOTS ACROSS THE COASTAL WATERS AND MAY
ACTUALLY INCREASE TOWARD 25 KNOTS FOR A SHORT PERIOD BETWEEN 7-9 PM
AHEAD OF THE COLD FRONT...NOW MOVING INTO THE WESTERN PORTIONS OF
THE COASTAL PLAIN. THIS FRONT SHOULD PUSH OFF THE COAST LATE THIS
EVENING WITH WINDS VEERING AROUND TO THE NW AND DIMINISHING TO 15
KNOTS OR LESS. SEAS HAVE BUILT TO 6 FEET OUT AT FRYING PAN
SHOALS...WITH BUOYS CLOSER TO SHORE READING ANYWHERE FROM 2-5 FEET
DEPENDING ON HOW OPEN THEY ARE TO FETCH FROM SW WINDS.

THE BIGGEST CHANGE WITH THIS FORECAST UPDATE WAS TO INCREASE
FORECAST WAVES ALONG THE BRUNSWICK COUNTY BEACHES BY ~3 FEET TO 4-5
FEET GIVEN THE LONG ONSHORE FETCH. WHEN WAVE DATA WAS AVAILABLE FROM
THE OCEAN CREST PIER (STILL OUT OF SERVICE AT THIS TIME) IT TAUGHT
US A LOT ABOUT WAVE BEHAVIOR HERE GIVEN VARIOUS WIND DIRECTIONS.
ONCE WINDS VEER NW BEHIND THE FRONT SEAS SHOULD BEGIN TO DIMINISH.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 345 PM TUESDAY...BUMPY SEAS WILL LINGER INTO DAYBREAK
WEDNESDAY AS AN EXERCISE CAUTION STATEMENT RUNS THROUGH 12Z/7AM
WEDNESDAY. SW WAVES 2-4 FT EVERY 4 SECONDS WILL CO-MINGLE WITH
LIGHT NW CHOP AND ESE WAVE 1 FT OR LESS EVERY 10-11 SECONDS FOR A
GOOD PART OF WED BEFORE WIND-WAVES EASE IN THE AFTN. BY THU 2 FT
SEAS ON THE WATERS AND LIGHT N-NNE WIND. NO TSTMS OR RESTRICTIONS
TO VISIBILITY ON THE 0-20NM WATERS WED/THU.

LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 345 PM TUESDAY...FLOW REMAINS MOSTLY NORTHERLY ON FRIDAY
WITH HIGH PRESSURE ENTRENCHED ACROSS MOST OF THE NORTHEAST AND
MID-ATLANTIC. LOW PRESSURE DEVELOPING ALONG THE GULF STATES TO MOVE
VERY SLOWLY EASTWARD. THIS SYSTEM WILL AFFECT THE AREA ON
SATURDAY...REMAINING TO OUR SOUTH AS IT PASSES BY. THE ENCROACHING
WARM FRONT MAY VEER THE FLOW OVER PART OF THE REGION BUT ITS TOUGH
TO SAY EXACTLY HOW FAR NORTH THIS BOUNDARY TRAVERSES. REGARDLESS
WIND AND SEAS BOTH TO REMAIN BELOW ADVISORY OR SCEC REALM THROUGH
THE PERIOD. NORTHWESTERLY WINDS GET UNDERWAY SUNDAY AS THIS SYSTEM
EXITS...ONCE AGAIN WITH NO REAL STRENGTH TO THE GRADIENT AND THUS
NO CONCERN FOR ANY CAUTIONARY HEADLINES.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...III
NEAR TERM...TRA
SHORT TERM...MJC
LONG TERM...MBB
AVIATION...DCH/MRR





AREA FORECAST DISCUSSION

NWS GRAND FORKS ND

 1248 PM CST WED DEC 17 2014

.UPDATE...
ISSUED AT 1237 PM CST WED DEC 17 2014

LITTLE CHANGES TO THE FORECAST WITH SFC HIGH PRESSURE CENTERED
OVER NE ND GIVING THE CLEAR SKIES TO MOST OF THE AREA WITH MID
CLOUDS DIMINISHING ACROSS NW MN. TEMPERATURES ARE RESPONDING WELL
TO THE FULL SUN...EVEN AT ITS LOW ELEVATION...WITH THE LACK OF
SNOW PACK...AND WILL TWEAK THEM UP A TOUCH FOR THE AFTN MAXES.

&&

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 309 AM CST WED DEC 17 2014

TEMPERATURES WILL BE THE MAIN ISSUE FOR THE SHORT TERM.

THE UPPER LOW OVER THE GREAT LAKES WILL PULL FURTHER AWAY FROM THE
PLAINS TODAY...WITH SOME SLIGHTLY HIGHER HEIGHTS MOVING IN BEHIND.
SFC HIGH PRESSURE WILL CONTINUE TO EXTEND FROM CANADA INTO THE
CWA. CLOUDS CONTINUE OVER OUR EASTERN COUNTIES AND WILL HAVE TO
WATCH IF THEY PUSH FURTHER WEST. THINK THAT MORE CLOUDS WILL MOVE
INTO THE VALLEY TOWARDS SUNRISE BUT THINK THAT THEY SHOULD BE
SHORT LIVED AS THE RAP HAS RH VALUES DECREASING A BIT AS WE HEAD
INTO THE DAY. KEPT EAST OF THE RED RIVER IN THE MOSTLY CLOUDY
RANGE. TEMPS THIS MORNING IN THE WEST HAVE DROPPED BELOW ZERO
UNDER CLEAR SKIES...BUT THINK THERE SHOULD BE ENOUGH SUN TO GET
BACK INTO THE TEENS FOR HIGHS.

TONIGHT...A WEAK SHORTWAVE WILL MOVE INTO THE WESTERN DAKOTAS...BUT
NOT MUCH MOISTURE WITH IT ACCORDING TO THE MODELS. THE SFC HIGH
WILL START TO MOVE EAST IN RESPONSE...WITH SOUTHERLY WINDS
RETURNING. AT THIS POINT THINK THE WESTERN COUNTIES WILL AGAIN SEE
CLEAR SKIES BUT SOME MIXING FROM WINDS WILL KEEP TEMPS ABOVE ZERO
WHILE THE EAST WILL HAVE CLOUDS AND BE NEAR 10 DEGREES. THE
SOUTHERLY WINDS WILL PICK UP ON THURSDAY AND THERE SHOULD BE SOME
INCREASING CLOUDS THROUGHOUT THE DAY AS MOISTURE RETURN PICKS UP.
THERE WILL ALSO BE SOME WARM AIR ADVECTION SO TEMPS SHOULD BE ABLE
TO RETURN TO THE 20S.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 309 AM CST WED DEC 17 2014

THURSDAY NIGHT THROUGH FRIDAY NIGHT...THE WEAK UPPER TROUGH
CONTINUES TO MAKE ITS WAY ACROSS THE NORTHERN PLAINS. THE
SOUTHERLY WINDS AND WARM AIR ADVECTION WILL CONTINUE...WITH THE
MODELS SHOWING SOME ISENTROPIC LIFT MOVING IN LATE THURSDAY NIGHT
AND INTO FRIDAY. CONDENSATION PRESSURE DEFICITS ARE NOT OVERLY
HIGH AND LIFT IS PRETTY WEAK. MODELS ALL PUT OUT VERY MINIMAL QPF
BUT SOME LIGHT SNOW IS NOT OUT OF THE QUESTION. KEPT SOME LOW POPS
GOING FRIDAY...BUT ANY ACCUMULATIONS WILL BE MINIMAL. TEMPS WILL
CONTINUE TO MODERATE WITH LOWS IN THE TEENS AND HIGHS ON FRIDAY
IN THE 20S.

FOR SATURDAY THROUGH TUESDAY...WEATHER OVER THE AREA IS EXPECTED
TO REMAIN FAIRLY TRANQUIL AS MOST OF THE JET ENERGY STAYS TO THE
SOUTH. SOUTHWESTERLY FLOW AT THE SFC BEHIND THE SFC RIDGE AND
INCREASING THICKNESS VALUES INDICATE A SLOW WARMING TREND...WITH
TEMPS REMAINING ABOVE NORMAL. NEXT CHANCE FOR PCPN WILL BE ON
MONDAY AS A WEAK PACIFIC WAVE CROSSES THE AREA.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1237 PM CST WED DEC 17 2014

HIGH PRESSURE OVER THE RED RIVER VALLEY WILL SLOWLY DRIFT EAST
TONIGHT WITH WINDS TURNING LIGHT SOUTHERLY IN THE RRV/ERN ND AFTER
00Z WHILE AREAS EAST OF THE VALLEY GOES LIGHT AND VARIABLE TONIGHT.
SKIES GENERALLY CLEAR TONIGHT.   THERE IS ONE PATCH OF MID CLOUD
TVF-FSE AREA MOVING WEST AND IT MAY MAKE IT TO GFK AT MID AFTN FOR A
FEW HOURS BUT ALSO MAY JUST DISSIPATE.  THE MVFR CIGS IN WRN ND WILL
STAY OUT IN THAT AREA  BUT COULD MOVE EAST SOME AS SOUTHERLY WINDS
GET MORE PRONOUNCED THURSDAY.  FOR NOW WILL KEEP LOWER CIGS WEST OF
DVL THRU 18Z THU.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...JK
SHORT TERM...JR
LONG TERM...JR/HOPKINS
AVIATION...RIDDLE







AREA FORECAST DISCUSSION

NWS BISMARCK ND

 1221 PM CST WED DEC 17 2014

.UPDATE...
ISSUED AT 1216 PM CST WED DEC 17 2014

EASTERN EDGE OF BROAD CLOUD COVER OVER WESTERN AND CENTRAL NORTH
DAKOTA HAS BEEN DOING SOME ERODING...THOUGH SOME AREAS THAT ERODED
HAD QUICK RE-DEVELOPMENT. WITH THAT SAID...WILL KEEP CLOUDS IN THE
FORECAST THROUGH THE AFTERNOON OVER AFOREMENTIONED AREAS AS EXPECT
ANY BREAKS THAT DO DEVELOP WILL NOT TAKE LONG TO FILL BACK IN.

UPDATE ISSUED AT 838 AM CST WED DEC 17 2014

BROAD AREA OF CLOUD COVER CONTINUES OVER THE WEST HALF OF THE
STATE AND HAS BEEN TRYING TO BUILD A LITTLE TO THE EAST THIS
MORNING. FOR MORNING UPDATE HAVE ADJUSTED THE EASTERN EDGE A BIT
WITH CURRENT TRENDS. MODELS DIFFER A BIT ON WHETHER THE CLOUD
COVER WILL RETREAT SOME LATER TODAY...BUT FOR NOW WILL GO WITH
CONSISTENCY SINCE THIS HAS NOT BUDGED MUCH FOR THE PAST DAY.
UPDATES HAVE BEEN SENT.

UPDATE ISSUED AT 657 AM CST WED DEC 17 2014

CURRENT FORECAST LOOKS ON TRACK...NO CHANGES MADE. BLENDED IN
CURRENT OBSERVATIONS.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 302 AM CST WED DEC 17 2014

THE CHALLENGE TODAY IS SIMILAR TO TUESDAY WITH FORECASTING THE
MOVEMENT OF A DISTINCT/SHARP DELINEATION OF CLOUDS/NO
CLOUDS...ALIGNED FAIRLY CLOSE TO AND ALONG HIGHWAY 83 THIS
MORNING. A SOLID OVERCAST WITH ISOLATED FLURRIES DOMINATE ALONG
AND TO THE WEST OF THIS LINE...WITH MOSTLY CLEAR CONDITIONS
EXTENDING EAST OF THIS LINE. TEMPERATURES DEPENDENT ON THE
MOVEMENT OF THIS LINE TODAY/TONIGHT. IN ADDITION...THE APPROACH OF
SHORTWAVE TROUGH ALOFT AND A WARM FRONT INTO EASTERN MONTANA THIS
EVENING/WEDNESDAY NIGHT WILL RESULT IN ISENTROPIC LIFT AND A
SLIGHT CHANCE OF VERY LIGHT SNOW IN THE SOUTHWEST.

THE LATEST FOG/STRATUS IMAGERY LOOP REMAINS NEARLY UNCHANGED IN
THE LAST 6 HOURS WITH THE STRATUS LINE NUDGING A BIT FARTHER
EAST...NOW INTO MINOT AND LINTON AGAIN. THE HRRR/RAP13/NAM/GFS
925MB RH TREND SHOWS NEARLY A STATIONARY SITUATION WITH THE STRATUS
DECK DURING THE DAY...FOLLOWED BY A GRADUAL PUSH EAST WEDNESDAY
EVENING AND WEDNESDAY NIGHT. THE LATEST HRRR ALSO HAS PATCHY FOG
DEVELOPING ACROSS THE SOUTHWEST AS THE STRATUS DECK CONTINUES TO
LOWER THIS MORNING. THIS SEEMS REASONABLE AND HAVE ADDED THIS INTO THE
FORECAST THROUGH 18Z. AS MENTIONED ABOVE...ISENTROPIC LIFT PER NAM
285K PRESSURE SURFACE ACROSS THE SOUTHWEST LATER THIS AFTERNOON
INTO TONIGHT WILL BE ENOUGH FOR A SIGHT CHC MENTION OF LIGHT
SNOW...ALTHOUGH EXPECTING LIMITED AMOUNTS WITH LIQUID EQUIVALENCIES
OF BETWEEN ONE AND TWO HUNDREDTHS OF AN INCH. OTHERWISE CLOUDS
REMAIN IN-TACT THROUGH THE SHORT TERM PERIOD WEST WITH ISOLATED
FLURRIES...AND MOSTLY SUNNY EAST CENTRAL. HIGHS TODAY WILL RANGE
FROM LOWER TO MID TEENS FROM THE TURTLE MOUNTAINS SOUTH TO THE
JAMES RIVER VALLEY...TO THE LOWER 20S SOUTHWEST.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 302 AM CST WED DEC 17 2014

A QUIET START TO THE EXTENDED FORECAST TRANSITIONING INTO A
POTENTIALLY MORE ACTIVE PATTERN EARLY TO MID NEXT WEEK HIGHLIGHTS
THE LONG TERM.

THE 00 UTC GUIDANCE SUITE IS IN AGREEMENT ON SPLIT FLOW ACROSS THE
CENTRAL CONUS THURSDAY INTO SATURDAY...FAVORING HIGHS SLIGHTLY
ABOVE NORMAL IN THE MID 20S TO MID 30S AND DRY CONDITIONS.
THEREAFTER...ENERGY COMING ON SHORE TO THE PACIFIC NORTHWEST THIS
WEEKEND IS FORECAST TO PROPAGATE INTO THE CENTRAL CONUS LATE
SUNDAY INTO TUESDAY. THIS WOULD LEAD TO AN AMPLIFICATION OF THE
UPPER LEVEL PATTERN WITH A DEEPENING CENTRAL CONUS TROUGH. THIS
WILL HAVE TO BE MONITORED FOR POTENTIAL WINTER WEATHER CHRISTMAS
TRAVEL IMPACTS NEXT WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1216 PM CST WED DEC 17 2014

WIDESPREAD MVFR CIGS WITH LCL IFR CIGS WILL REMAIN OVER WESTERN
INTO PARTS OF CENTRAL NORTH DAKOTA TODAY. EXPECT LOWER CIGS TO
SPREAD EASTWARD OVERNIGHT.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...JJS
SHORT TERM...KS
LONG TERM...AYD
AVIATION...JJS







AREA FORECAST DISCUSSION

NWS GRAND FORKS ND

 947 AM CST WED DEC 17 2014

.UPDATE...
ISSUED AT 943 AM CST WED DEC 17 2014

MINIMAL CHANGES MADE TO THE FORECAST AS UPPER LEVEL TROUGH AND
ASSOCIATED 7000FT CLOUD DECK SWING SOUTH ACROSS NW MN TODAY. SFC
HIGH PRESSURE WILL KEEP SKIES CLEAR IN THE VALLEY AND WEST WITH
TEMPS ADJUSTED SLIGHTLY UPWARD AS GUIDANCE HAS BEEN COOL WITH LACK
OF SNOW COVER.

&&

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 309 AM CST WED DEC 17 2014

TEMPERATURES WILL BE THE MAIN ISSUE FOR THE SHORT TERM.

THE UPPER LOW OVER THE GREAT LAKES WILL PULL FURTHER AWAY FROM THE
PLAINS TODAY...WITH SOME SLIGHTLY HIGHER HEIGHTS MOVING IN BEHIND.
SFC HIGH PRESSURE WILL CONTINUE TO EXTEND FROM CANADA INTO THE
CWA. CLOUDS CONTINUE OVER OUR EASTERN COUNTIES AND WILL HAVE TO
WATCH IF THEY PUSH FURTHER WEST. THINK THAT MORE CLOUDS WILL MOVE
INTO THE VALLEY TOWARDS SUNRISE BUT THINK THAT THEY SHOULD BE
SHORT LIVED AS THE RAP HAS RH VALUES DECREASING A BIT AS WE HEAD
INTO THE DAY. KEPT EAST OF THE RED RIVER IN THE MOSTLY CLOUDY
RANGE. TEMPS THIS MORNING IN THE WEST HAVE DROPPED BELOW ZERO
UNDER CLEAR SKIES...BUT THINK THERE SHOULD BE ENOUGH SUN TO GET
BACK INTO THE TEENS FOR HIGHS.

TONIGHT...A WEAK SHORTWAVE WILL MOVE INTO THE WESTERN DAKOTAS...BUT
NOT MUCH MOISTURE WITH IT ACCORDING TO THE MODELS. THE SFC HIGH
WILL START TO MOVE EAST IN RESPONSE...WITH SOUTHERLY WINDS
RETURNING. AT THIS POINT THINK THE WESTERN COUNTIES WILL AGAIN SEE
CLEAR SKIES BUT SOME MIXING FROM WINDS WILL KEEP TEMPS ABOVE ZERO
WHILE THE EAST WILL HAVE CLOUDS AND BE NEAR 10 DEGREES. THE
SOUTHERLY WINDS WILL PICK UP ON THURSDAY AND THERE SHOULD BE SOME
INCREASING CLOUDS THROUGHOUT THE DAY AS MOISTURE RETURN PICKS UP.
THERE WILL ALSO BE SOME WARM AIR ADVECTION SO TEMPS SHOULD BE ABLE
TO RETURN TO THE 20S.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 309 AM CST WED DEC 17 2014

THURSDAY NIGHT THROUGH FRIDAY NIGHT...THE WEAK UPPER TROUGH
CONTINUES TO MAKE ITS WAY ACROSS THE NORTHERN PLAINS. THE
SOUTHERLY WINDS AND WARM AIR ADVECTION WILL CONTINUE...WITH THE
MODELS SHOWING SOME ISENTROPIC LIFT MOVING IN LATE THURSDAY NIGHT
AND INTO FRIDAY. CONDENSATION PRESSURE DEFICITS ARE NOT OVERLY
HIGH AND LIFT IS PRETTY WEAK. MODELS ALL PUT OUT VERY MINIMAL QPF
BUT SOME LIGHT SNOW IS NOT OUT OF THE QUESTION. KEPT SOME LOW POPS
GOING FRIDAY...BUT ANY ACCUMULATIONS WILL BE MINIMAL. TEMPS WILL
CONTINUE TO MODERATE WITH LOWS IN THE TEENS AND HIGHS ON FRIDAY
IN THE 20S.

FOR SATURDAY THROUGH TUESDAY...WEATHER OVER THE AREA IS EXPECTED
TO REMAIN FAIRLY TRANQUIL AS MOST OF THE JET ENERGY STAYS TO THE
SOUTH. SOUTHWESTERLY FLOW AT THE SFC BEHIND THE SFC RIDGE AND
INCREASING THICKNESS VALUES INDICATE A SLOW WARMING TREND...WITH
TEMPS REMAINING ABOVE NORMAL. NEXT CHANCE FOR PCPN WILL BE ON
MONDAY AS A WEAK PACIFIC WAVE CROSSES THE AREA.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 638 AM CST WED DEC 17 2014

IFR CIGS AND A FEW FLURRIES CONTINUE AT KBJI WITH THE REST OF THE
CWA SEEING CLEAR SKIES. THINK THAT KBJI SHOULD RECOVER TO MVFR BY
MID MORNING AND THEN SCATTER OUT IN THE AFTERNOON. VFR CONDITIONS
WILL REMAIN OVER THE REST OF THE CWA WITH LIGHT AND VARIABLE
WINDS. WINDS WILL SETTLE DOWN OUT OF THE SOUTHEAST BY LATE IN THE
PERIOD BUT WILL STILL BE WELL BELOW 10 KTS.


&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...JK
SHORT TERM...JR
LONG TERM...JR/HOPKINS
AVIATION...JR






AREA FORECAST DISCUSSION

NWS BISMARCK ND

 847 AM CST WED DEC 17 2014

.UPDATE...
ISSUED AT 838 AM CST WED DEC 17 2014

BROAD AREA OF CLOUD COVER CONTINUES OVER THE WEST HALF OF THE
STATE AND HAS BEEN TRYING TO BUILD A LITTLE TO THE EAST THIS
MORNING. FOR MORNING UPDATE HAVE ADJUSTED THE EASTERN EDGE A BIT
WITH CURRENT TRENDS. MODELS DIFFER A BIT ON WHETHER THE CLOUD
COVER WILL RETREAT SOME LATER TODAY...BUT FOR NOW WILL GO WITH
CONSISTENCY SINCE THIS HAS NOT BUDGED MUCH FOR THE PAST DAY.
UPDATES HAVE BEEN SENT.

UPDATE ISSUED AT 657 AM CST WED DEC 17 2014

CURRENT FORECAST LOOKS ON TRACK...NO CHANGES MADE. BLENDED IN
CURRENT OBSERVATIONS.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 302 AM CST WED DEC 17 2014

THE CHALLENGE TODAY IS SIMILAR TO TUESDAY WITH FORECASTING THE
MOVEMENT OF A DISTINCT/SHARP DELINEATION OF CLOUDS/NO
CLOUDS...ALIGNED FAIRLY CLOSE TO AND ALONG HIGHWAY 83 THIS
MORNING. A SOLID OVERCAST WITH ISOLATED FLURRIES DOMINATE ALONG
AND TO THE WEST OF THIS LINE...WITH MOSTLY CLEAR CONDITIONS
EXTENDING EAST OF THIS LINE. TEMPERATURES DEPENDENT ON THE
MOVEMENT OF THIS LINE TODAY/TONIGHT. IN ADDITION...THE APPROACH OF
SHORTWAVE TROUGH ALOFT AND A WARM FRONT INTO EASTERN MONTANA THIS
EVENING/WEDNESDAY NIGHT WILL RESULT IN ISENTROPIC LIFT AND A
SLIGHT CHANCE OF VERY LIGHT SNOW IN THE SOUTHWEST.

THE LATEST FOG/STRATUS IMAGERY LOOP REMAINS NEARLY UNCHANGED IN
THE LAST 6 HOURS WITH THE STRATUS LINE NUDGING A BIT FARTHER
EAST...NOW INTO MINOT AND LINTON AGAIN. THE HRRR/RAP13/NAM/GFS
925MB RH TREND SHOWS NEARLY A STATIONARY SITUATION WITH THE STRATUS
DECK DURING THE DAY...FOLLOWED BY A GRADUAL PUSH EAST WEDNESDAY
EVENING AND WEDNESDAY NIGHT. THE LATEST HRRR ALSO HAS PATCHY FOG
DEVELOPING ACROSS THE SOUTHWEST AS THE STRATUS DECK CONTINUES TO
LOWER THIS MORNING. THIS SEEMS REASONABLE AND HAVE ADDED THIS INTO THE
FORECAST THROUGH 18Z. AS MENTIONED ABOVE...ISENTROPIC LIFT PER NAM
285K PRESSURE SURFACE ACROSS THE SOUTHWEST LATER THIS AFTERNOON
INTO TONIGHT WILL BE ENOUGH FOR A SIGHT CHC MENTION OF LIGHT
SNOW...ALTHOUGH EXPECTING LIMITED AMOUNTS WITH LIQUID EQUIVALENCIES
OF BETWEEN ONE AND TWO HUNDREDTHS OF AN INCH. OTHERWISE CLOUDS
REMAIN IN-TACT THROUGH THE SHORT TERM PERIOD WEST WITH ISOLATED
FLURRIES...AND MOSTLY SUNNY EAST CENTRAL. HIGHS TODAY WILL RANGE
FROM LOWER TO MID TEENS FROM THE TURTLE MOUNTAINS SOUTH TO THE
JAMES RIVER VALLEY...TO THE LOWER 20S SOUTHWEST.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 302 AM CST WED DEC 17 2014

A QUIET START TO THE EXTENDED FORECAST TRANSITIONING INTO A
POTENTIALLY MORE ACTIVE PATTERN EARLY TO MID NEXT WEEK HIGHLIGHTS
THE LONG TERM.

THE 00 UTC GUIDANCE SUITE IS IN AGREEMENT ON SPLIT FLOW ACROSS THE
CENTRAL CONUS THURSDAY INTO SATURDAY...FAVORING HIGHS SLIGHTLY
ABOVE NORMAL IN THE MID 20S TO MID 30S AND DRY CONDITIONS.
THEREAFTER...ENERGY COMING ON SHORE TO THE PACIFIC NORTHWEST THIS
WEEKEND IS FORECAST TO PROPAGATE INTO THE CENTRAL CONUS LATE
SUNDAY INTO TUESDAY. THIS WOULD LEAD TO AN AMPLIFICATION OF THE
UPPER LEVEL PATTERN WITH A DEEPENING CENTRAL CONUS TROUGH. THIS
WILL HAVE TO BE MONITORED FOR POTENTIAL WINTER WEATHER CHRISTMAS
TRAVEL IMPACTS NEXT WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 302 AM CST WED DEC 17 2014

WIDESPREAD/SOLID MVFR CIGS AT KISN/KBIS NEXT 24HR. IFR CIGS AND AT
KDIK THROUGH 01Z THURSDAY...AND POSSIBLE PATCHY FOG AT THE TERMINAL
THROUGH 18Z. A VCFG HAS BEEN INCLUDED AT KDIK. KMOT HAS BEEN
WOBBLING ON THE EDGE OF THE STRATUS LINE...AND IT APPEARS KMOT WILL
JUST BARELY REMAIN WITHIN THE MVFR STRATUS DECK. KJMS WILL CONTINUE
WITH VFR CIGS/MOSTLY CLEAR SKY UNTIL 03Z THURSDAY...FOLLOWED BY
MVFR/IFR CIGS.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...JJS
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS






AREA FORECAST DISCUSSION

NWS BISMARCK ND

 657 AM CST WED DEC 17 2014

.UPDATE...
ISSUED AT 657 AM CST WED DEC 17 2014

CURRENT FORECAST LOOKS ON TRACK...NO CHANGES MADE. BLENDED IN
CURRENT OBSERVATIONS.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 302 AM CST WED DEC 17 2014

THE CHALLENGE TODAY IS SIMILAR TO TUESDAY WITH FORECASTING THE
MOVEMENT OF A DISTINCT/SHARP DELINEATION OF CLOUDS/NO
CLOUDS...ALIGNED FAIRLY CLOSE TO AND ALONG HIGHWAY 83 THIS
MORNING. A SOLID OVERCAST WITH ISOLATED FLURRIES DOMINATE ALONG
AND TO THE WEST OF THIS LINE...WITH MOSTLY CLEAR CONDITIONS
EXTENDING EAST OF THIS LINE. TEMPERATURES DEPENDENT ON THE
MOVEMENT OF THIS LINE TODAY/TONIGHT. IN ADDITION...THE APPROACH OF
SHORTWAVE TROUGH ALOFT AND A WARM FRONT INTO EASTERN MONTANA THIS
EVENING/WEDNESDAY NIGHT WILL RESULT IN ISENTROPIC LIFT AND A
SLIGHT CHANCE OF VERY LIGHT SNOW IN THE SOUTHWEST.

THE LATEST FOG/STRATUS IMAGERY LOOP REMAINS NEARLY UNCHANGED IN
THE LAST 6 HOURS WITH THE STRATUS LINE NUDGING A BIT FARTHER
EAST...NOW INTO MINOT AND LINTON AGAIN. THE HRRR/RAP13/NAM/GFS
925MB RH TREND SHOWS NEARLY A STATIONARY SITUATION WITH THE STRATUS
DECK DURING THE DAY...FOLLOWED BY A GRADUAL PUSH EAST WEDNESDAY
EVENING AND WEDNESDAY NIGHT. THE LATEST HRRR ALSO HAS PATCHY FOG
DEVELOPING ACROSS THE SOUTHWEST AS THE STRATUS DECK CONTINUES TO
LOWER THIS MORNING. THIS SEEMS REASONABLE AND HAVE ADDED THIS INTO THE
FORECAST THROUGH 18Z. AS MENTIONED ABOVE...ISENTROPIC LIFT PER NAM
285K PRESSURE SURFACE ACROSS THE SOUTHWEST LATER THIS AFTERNOON
INTO TONIGHT WILL BE ENOUGH FOR A SIGHT CHC MENTION OF LIGHT
SNOW...ALTHOUGH EXPECTING LIMITED AMOUNTS WITH LIQUID EQUIVALENCIES
OF BETWEEN ONE AND TWO HUNDREDTHS OF AN INCH. OTHERWISE CLOUDS
REMAIN IN-TACT THROUGH THE SHORT TERM PERIOD WEST WITH ISOLATED
FLURRIES...AND MOSTLY SUNNY EAST CENTRAL. HIGHS TODAY WILL RANGE
FROM LOWER TO MID TEENS FROM THE TURTLE MOUNTAINS SOUTH TO THE
JAMES RIVER VALLEY...TO THE LOWER 20S SOUTHWEST.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 302 AM CST WED DEC 17 2014

A QUIET START TO THE EXTENDED FORECAST TRANSITIONING INTO A
POTENTIALLY MORE ACTIVE PATTERN EARLY TO MID NEXT WEEK HIGHLIGHTS
THE LONG TERM.

THE 00 UTC GUIDANCE SUITE IS IN AGREEMENT ON SPLIT FLOW ACROSS THE
CENTRAL CONUS THURSDAY INTO SATURDAY...FAVORING HIGHS SLIGHTLY
ABOVE NORMAL IN THE MID 20S TO MID 30S AND DRY CONDITIONS.
THEREAFTER...ENERGY COMING ON SHORE TO THE PACIFIC NORTHWEST THIS
WEEKEND IS FORECAST TO PROPAGATE INTO THE CENTRAL CONUS LATE
SUNDAY INTO TUESDAY. THIS WOULD LEAD TO AN AMPLIFICATION OF THE
UPPER LEVEL PATTERN WITH A DEEPENING CENTRAL CONUS TROUGH. THIS
WILL HAVE TO BE MONITORED FOR POTENTIAL WINTER WEATHER CHRISTMAS
TRAVEL IMPACTS NEXT WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 302 AM CST WED DEC 17 2014

WIDESPREAD/SOLID MVFR CIGS AT KISN/KBIS NEXT 24HR. IFR CIGS AND AT
KDIK THROUGH 01Z THURSDAY...AND POSSIBLE PATCHY FOG AT THE TERMINAL
THROUGH 18Z. A VCFG HAS BEEN INCLUDED AT KDIK. KMOT HAS BEEN
WOBBLING ON THE EDGE OF THE STRATUS LINE...AND IT APPEARS KMOT WILL
JUST BARELY REMAIN WITHIN THE MVFR STRATUS DECK. KJMS WILL CONTINUE
WITH VFR CIGS/MOSTLY CLEAR SKY UNTIL 03Z THURSDAY...FOLLOWED BY
MVFR/IFR CIGS.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...AC
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS







AREA FORECAST DISCUSSION

NWS GRAND FORKS ND

 638 AM CST WED DEC 17 2014

.UPDATE...
ISSUED AT 638 AM CST WED DEC 17 2014

ADJUSTED CLOUD COVER...AS THE EDGE OF THE STRATUS HAS STAYED
FURTHER EAST. THE RAP AND NAM BOTH HAVE THE HIGHER 925 TO 850 RH
VALUES MOVING WEST INTO THE VALLEY THIS MORNING...BUT DECREASE
THAT SATURATION. WILL KEEP MOST OF THE CLOUDS IN THE EAST ALONG
WITH A FLURRY MENTION IN THE KBJI MENTION FOR THE NEXT FEW HOURS.
THE WEST SHOULD STAY MOSTLY CLEAR.

&&

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 309 AM CST WED DEC 17 2014

TEMPERATURES WILL BE THE MAIN ISSUE FOR THE SHORT TERM.

THE UPPER LOW OVER THE GREAT LAKES WILL PULL FURTHER AWAY FROM THE
PLAINS TODAY...WITH SOME SLIGHTLY HIGHER HEIGHTS MOVING IN BEHIND.
SFC HIGH PRESSURE WILL CONTINUE TO EXTEND FROM CANADA INTO THE
CWA. CLOUDS CONTINUE OVER OUR EASTERN COUNTIES AND WILL HAVE TO
WATCH IF THEY PUSH FURTHER WEST. THINK THAT MORE CLOUDS WILL MOVE
INTO THE VALLEY TOWARDS SUNRISE BUT THINK THAT THEY SHOULD BE
SHORT LIVED AS THE RAP HAS RH VALUES DECREASING A BIT AS WE HEAD
INTO THE DAY. KEPT EAST OF THE RED RIVER IN THE MOSTLY CLOUDY
RANGE. TEMPS THIS MORNING IN THE WEST HAVE DROPPED BELOW ZERO
UNDER CLEAR SKIES...BUT THINK THERE SHOULD BE ENOUGH SUN TO GET
BACK INTO THE TEENS FOR HIGHS.

TONIGHT...A WEAK SHORTWAVE WIL MOVE INTO THE WESTERN DAKOTAS...BUT
NOT MUCH MOISTURE WITH IT ACCORDING TO THE MODELS. THE SFC HIGH
WILL START TO MOVE EAST IN RESPONSE...WITH SOUTHERLY WINDS
RETURNING. AT THIS POINT THINK THE WESTERN COUNTIES WILL AGAIN SEE
CLEAR SKIES BUT SOME MIXING FROM WINDS WILL KEEP TEMPS ABOVE ZERO
WHILE THE EAST WILL HAVE CLOUDS AND BE NEAR 10 DEGREES. THE
SOUTHERLY WINDS WILL PICK UP ON THURSDAY AND THERE SHOULD BE SOME
INCREASING CLOUDS THROUGHOUT THE DAY AS MOISTURE RETURN PICKS UP.
THERE WILL ALSO BE SOME WARM AIR ADVECTION SO TEMPS SHOULD BE ABLE
TO RETURN TO THE 20S.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 309 AM CST WED DEC 17 2014

THURSDAY NIGHT THROUGH FRIDAY NIGHT...THE WEAK UPPER TROUGH
CONTINUES TO MAKE ITS WAY ACROSS THE NORTHERN PLAINS. THE
SOUTHERLY WINDS AND WARM AIR ADVECTION WILL CONTINUE...WITH THE
MODELS SHOWING SOME ISENTROPIC LIFT MOVING IN LATE THURSDAY NIGHT
AND INTO FRIDAY. CONDENSATION PRESSURE DEFICITS ARE NOT OVERLY
HIGH AND LIFT IS PRETTY WEAK. MODELS ALL PUT OUT VERY MINIMAL QPF
BUT SOME LIGHT SNOW IS NOT OUT OF THE QUESTION. KEPT SOME LOW POPS
GOING FRIDAY...BUT ANY ACCUMULATIONS WILL BE MINIMAL. TEMPS WILL
CONTINUE TO MODERATE WITH LOWS IN THE TEENS AND HIGHS ON FRIDAY
IN THE 20S.

FOR SATURDAY THROUGH TUESDAY...WEATHER OVER THE AREA IS EXPECTED
TO REMAIN FAIRLY TRANQUIL AS MOST OF THE JET ENERGY STAYS TO THE
SOUTH. SOUTHWESTERLY FLOW AT THE SFC BEHIND THE SFC RIDGE AND
INCREASING THICKNESS VALUES INDICATE A SLOW WARMING TREND...WITH
TEMPS REMAINING ABOVE NORMAL. NEXT CHANCE FOR PCPN WILL BE ON
MONDAY AS A WEAK PACIFIC WAVE CROSSES THE AREA.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 638 AM CST WED DEC 17 2014

IFR CIGS AND A FEW FLURRIES CONTINUE AT KBJI WITH THE REST OF THE
CWA SEEING CLEAR SKIES. THINK THAT KBJI SHOULD RECOVER TO MVFR BY
MID MORNING AND THEN SCATTER OUT IN THE AFTERNOON. VFR CONDITIONS
WILL REMAIN OVER THE REST OF THE CWA WITH LIGHT AND VARIABLE
WINDS. WINDS WILL SETTLE DOWN OUT OF THE SOUTHEAST BY LATE IN THE
PERIOD BUT WILL STILL BE WELL BELOW 10 KTS.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...JR
SHORT TERM...JR
LONG TERM...JR/HOPKINS
AVIATION...JR







AREA FORECAST DISCUSSION

NWS GRAND FORKS ND

 310 AM CST WED DEC 17 2014

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 309 AM CST WED DEC 17 2014

TEMPERATURES WILL BE THE MAIN ISSUE FOR THE SHORT TERM.

THE UPPER LOW OVER THE GREAT LAKES WILL PULL FURTHER AWAY FROM THE
PLAINS TODAY...WITH SOME SLIGHTLY HIGHER HEIGHTS MOVING IN BEHIND.
SFC HIGH PRESSURE WILL CONTINUE TO EXTEND FROM CANADA INTO THE
CWA. CLOUDS CONTINUE OVER OUR EASTERN COUNTIES AND WILL HAVE TO
WATCH IF THEY PUSH FURTHER WEST. THINK THAT MORE CLOUDS WILL MOVE
INTO THE VALLEY TOWARDS SUNRISE BUT THINK THAT THEY SHOULD BE
SHORT LIVED AS THE RAP HAS RH VALUES DECREASING A BIT AS WE HEAD
INTO THE DAY. KEPT EAST OF THE RED RIVER IN THE MOSTLY CLOUDY
RANGE. TEMPS THIS MORNING IN THE WEST HAVE DROPPED BELOW ZERO
UNDER CLEAR SKIES...BUT THINK THERE SHOULD BE ENOUGH SUN TO GET
BACK INTO THE TEENS FOR HIGHS.

TONIGHT...A WEAK SHORTWAVE WIL MOVE INTO THE WESTERN DAKOTAS...BUT
NOT MUCH MOISTURE WITH IT ACCORDING TO THE MODELS. THE SFC HIGH
WILL START TO MOVE EAST IN RESPONSE...WITH SOUTHERLY WINDS
RETURNING. AT THIS POINT THINK THE WESTERN COUNTIES WILL AGAIN SEE
CLEAR SKIES BUT SOME MIXING FROM WINDS WILL KEEP TEMPS ABOVE ZERO
WHILE THE EAST WILL HAVE CLOUDS AND BE NEAR 10 DEGREES. THE
SOUTHERLY WINDS WILL PICK UP ON THURSDAY AND THERE SHOULD BE SOME
INCREASING CLOUDS THROUGHOUT THE DAY AS MOISTURE RETURN PICKS UP.
THERE WILL ALSO BE SOME WARM AIR ADVECTION SO TEMPS SHOULD BE ABLE
TO RETURN TO THE 20S.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 309 AM CST WED DEC 17 2014

THURSDAY NIGHT THROUGH FRIDAY NIGHT...THE WEAK UPPER TROUGH
CONTINUES TO MAKE ITS WAY ACROSS THE NORTHERN PLAINS. THE
SOUTHERLY WINDS AND WARM AIR ADVECTION WILL CONTINUE...WITH THE
MODELS SHOWING SOME ISENTROPIC LIFT MOVING IN LATE THURSDAY NIGHT
AND INTO FRIDAY. CONDENSATION PRESSURE DEFICITS ARE NOT OVERLY
HIGH AND LIFT IS PRETTY WEAK. MODELS ALL PUT OUT VERY MINIMAL QPF
BUT SOME LIGHT SNOW IS NOT OUT OF THE QUESTION. KEPT SOME LOW POPS
GOING FRIDAY...BUT ANY ACCUMULATIONS WILL BE MINIMAL. TEMPS WILL
CONTINUE TO MODERATE WITH LOWS IN THE TEENS AND HIGHS ON FRIDAY
IN THE 20S.

FOR SATURDAY THROUGH TUESDAY...WEATHER OVER THE AREA IS EXPECTED
TO REMAIN FAIRLY TRANQUIL AS MOST OF THE JET ENERGY STAYS TO THE
SOUTH. SOUTHWESTERLY FLOW AT THE SFC BEHIND THE SFC RIDGE AND
INCREASING THICKNESS VALUES INDICATE A SLOW WARMING TREND...WITH
TEMPS REMAINING ABOVE NORMAL. NEXT CHANCE FOR PCPN WILL BE ON
MONDAY AS A WEAK PACIFIC WAVE CROSSES THE AREA.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1130 PM CST TUE DEC 16 2014

MODEL RH FIELDS...AS WELL AS THE HRRR/RAP GUIDANCE TO AN
EXTENT...BRING CLOUDS BACK WEST (SATELLITE IMAGERY CONFIRMS THIS
SCENARIO). THE MOST PROBABLE SOLUTION IS THAT KDVL REMAINS
CLEAR...VFR CLOUDS (@4000FT) MOVE INTO THE VALLEY SITES...WITH
MVFR CIGS INTO KBJI. ANTICIPATE A SLOW CLEARING TREND DURING THE
DAY WEDNESDAY. WINDS WILL BE LIGHT.


&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

SHORT TERM...JR
LONG TERM...JR/HOPKINS
AVIATION...TG








AREA FORECAST DISCUSSION

NWS BISMARCK ND

 302 AM CST WED DEC 17 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 302 AM CST WED DEC 17 2014

THE CHALLENGE TODAY IS SIMILAR TO TUESDAY WITH FORECASTING THE
MOVEMENT OF A DISTINCT/SHARP DELINEATION OF CLOUDS/NO
CLOUDS...ALIGNED FAIRLY CLOSE TO AND ALONG HIGHWAY 83 THIS
MORNING. A SOLID OVERCAST WITH ISOLATED FLURRIES DOMINATE ALONG
AND TO THE WEST OF THIS LINE...WITH MOSTLY CLEAR CONDITIONS
EXTENDING EAST OF THIS LINE. TEMPERATURES DEPENDENT ON THE
MOVEMENT OF THIS LINE TODAY/TONIGHT. IN ADDITION...THE APPROACH OF
SHORTWAVE TROUGH ALOFT AND A WARM FRONT INTO EASTERN MONTANA THIS
EVENING/WEDNESDAY NIGHT WILL RESULT IN ISENTROPIC LIFT AND A
SLIGHT CHANCE OF VERY LIGHT SNOW IN THE SOUTHWEST.

THE LATEST FOG/STRATUS IMAGERY LOOP REMAINS NEARLY UNCHANGED IN
THE LAST 6 HOURS WITH THE STRATUS LINE NUDGING A BIT FARTHER
EAST...NOW INTO MINOT AND LINTON AGAIN. THE HRRR/RAP13/NAM/GFS
925MB RH TREND SHOWS NEARLY A STATIONARY SITUATION WITH THE STRATUS
DECK DURING THE DAY...FOLLOWED BY A GRADUAL PUSH EAST WEDNESDAY
EVENING AND WEDNESDAY NIGHT. THE LATEST HRRR ALSO HAS PATCHY FOG
DEVELOPING ACROSS THE SOUTHWEST AS THE STRATUS DECK CONTINUES TO
LOWER THIS MORNING. THIS SEEMS REASONABLE AND HAVE ADDED THIS INTO THE
FORECAST THROUGH 18Z. AS MENTIONED ABOVE...ISENTROPIC LIFT PER NAM
285K PRESSURE SURFACE ACROSS THE SOUTHWEST LATER THIS AFTERNOON
INTO TONIGHT WILL BE ENOUGH FOR A SIGHT CHC MENTION OF LIGHT
SNOW...ALTHOUGH EXPECTING LIMITED AMOUNTS WITH LIQUID EQUIVALENCIES
OF BETWEEN ONE AND TWO HUNDREDTHS OF AN INCH. OTHERWISE CLOUDS
REMAIN IN-TACT THROUGH THE SHORT TERM PERIOD WEST WITH ISOLATED
FLURRIES...AND MOSTLY SUNNY EAST CENTRAL. HIGHS TODAY WILL RANGE
FROM LOWER TO MID TEENS FROM THE TURTLE MOUNTAINS SOUTH TO THE
JAMES RIVER VALLEY...TO THE LOWER 20S SOUTHWEST.


.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 302 AM CST WED DEC 17 2014

A QUIET START TO THE EXTENDED FORECAST TRANSITIONING INTO A
POTENTIALLY MORE ACTIVE PATTERN EARLY TO MID NEXT WEEK HIGHLIGHTS
THE LONG TERM.

THE 00 UTC GUIDANCE SUITE IS IN AGREEMENT ON SPLIT FLOW ACROSS THE
CENTRAL CONUS THURSDAY INTO SATURDAY...FAVORING HIGHS SLIGHTLY
ABOVE NORMAL IN THE MID 20S TO MID 30S AND DRY CONDITIONS.
THEREAFTER...ENERGY COMING ON SHORE TO THE PACIFIC NORTHWEST THIS
WEEKEND IS FORECAST TO PROPAGATE INTO THE CENTRAL CONUS LATE
SUNDAY INTO TUESDAY. THIS WOULD LEAD TO AN AMPLIFICATION OF THE
UPPER LEVEL PATTERN WITH A DEEPENING CENTRAL CONUS TROUGH. THIS
WILL HAVE TO BE MONITORED FOR POTENTIAL WINTER WEATHER CHRISTMAS
TRAVEL IMPACTS NEXT WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 302 AM CST WED DEC 17 2014

WIDESPREAD/SOLID MVFR CIGS AT KISN/KBIS NEXT 24HR. IFR CIGS AND
AT KDIK THROUGH 01Z THURSDAY...AND THERE COULD BE PATCHY FOG AT
THE TERMINAL THROUGH 18Z. THIS MAY BE ADDED INTO THE 12Z TAFS.
KMOT HAS BEEN WOBBLING ON THE EDGE OF THE STRATUS LINE...AND IT
APPEARS NOW KMOT WILL REMAIN JUST WITHIN THE STRATUS DECK FOR MVFR
CIGS. KJMS WILL CONTINUE WITH VFR CIGS/MOSTLY CLEAR SKY.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS








AREA FORECAST DISCUSSION

NWS WILMINGTON OH

 855 PM EST THU DEC 18 2014

.SYNOPSIS...
A WEAKENING UPPER LEVEL DISTURBANCE MOVING THROUGH THE OHIO VALLEY
WILL RESULT IN A FEW SNOW FLURRIES OR SNOW SHOWERS THIS EVENING.
WEAK SURFACE HIGH PRESSURE WILL THEN PUSH SLOWLY EAST ACROSS THE
REGION THROUGH THE WEEKEND...LEADING TO PRIMARILY DRY CONDITIONS
AND NEAR NORMAL TEMPERATURES.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS THE SURFACE PRESSURE GRADIENT CONTINUES TO RELAX ACROSS THE
OHIO VALLEY...ASCENT FROM A WEAKENING MID-LEVEL WAVE IS ALSO
MOVING OFF TO THE EAST. THIS IS LEADING TO A DIMINISHING TREND IN
RADAR ECHOES...AND FLURRIES OVER THE ILN FORECAST AREA HAVE JUST
ABOUT ENDED.

FORECAST TRENDS ARE RIGHT ON TRACK...AND MIN TEMPS WERE NOT
ADJUSTED AT ALL. THE CLOUD FORECAST IS SIMILAR TO YESTERDAY...BUT
THERE HAS BEEN SOME EROSION IN THE LOWEST LAYER OF CLOUDS
(1500-2500 FEET) IN THE SOUTHERN HALF OF THE FORECAST AREA. THE
00Z KILN SOUNDING DOES NOT SHOW A WELL-DEFINED LAYER OF SATURATION
BELOW 800MB AS HAS BEEN THE CASE FOR THE PAST SEVERAL SOUNDINGS.
REGARDLESS...MID-LEVEL CLOUDS (6000-1000 FEET) ARE FAIRLY
THICK...AND SKY GRIDS REMAIN AT 90-100 PERCENT THROUGH THE
OVERNIGHT.

PREVIOUS DISCUSSION >
UPR LVL S/WV WILL PASS EAST ACRS OUR REGION THROUGH THIS EVENING.
FORCING IS WEAK WITH MOST AREAS JUST SEEING A FEW FLURRIES. THERE
COULD BE A FEW SNOW SHOWERS WITH JUST A LIGHT DUSTING ALONG THE
I-70 CORRIDOR WHERE DEEPEST MOISTURE WILL INTERSECT WEAK FORCING.
LOW LEVEL CLOUDS WILL CONTINUE TO BE AN ISSUE AS THE RAP MODEL
SHOWS REGION STAYING PRETTY MUCH OVERCAST OVERNIGHT. LOWS WILL
DROP INTO THE LOWER AND MID 20S.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
WEAK SFC HIGH PRESSURE WILL SLOWLY BUILD INTO THE AREA ON FRIDAY.
DESPITE THIS FEATURE...IT LOOKS LIKE LOW LEVEL MOISTURE WILL HANG
AROUND AS IT BECOMES TRAPPED UNDERNEATH THE HIGH. WILL CONTINUE
WITH MAINLY CLOUDY SKIES. HIGHS WILL RANGE FROM THE LOWER TO MID
30S.

FOR FRIDAY NIGHT INTO SATURDAY...LATEST MODEL FORECASTS KEEP THE
AFFECTS OF AN UPR LVL S/WV TO OUR SOUTH WHILE SFC RIDGING REMAINS
IN PLACE. IT IS DIFFICULT TO KNOW IF THE LOW LEVEL CLOUDS WILL
ERODE DURING THIS TIME FRAME. HOWEVER...WITH AN INCREASE IN MID
AND HIGH LEVEL MOISTURE...IT WILL LIKELY REMAIN MOSTLY CLOUDY. IT
WILL BE A LITTLE WARMER ON SATURDAY WITH HIGHS IN THE MID AND
UPPER 30S.

BY SATURDAY NIGHT...HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS
THE GREAT LAKES AND OHIO VALLEY WHILE A WEAK UPR LVL S/WV PASSES
ACRS THE SOUTHERN GREAT LAKES. PARTLY CLOUDY SKIES ARE EXPECTED.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE CENTERED TO THE NORTHEAST WILL BRING DRY WEATHER ON
SUNDAY. INCREASING MOISTURE AND LIFT WELL AHEAD OF DEVELOPING LOW
PRESSURE MAY PRODUCE LIGHT RAIN AND SNOW ON MONDAY. AS THE LOW MOVES
TO LAKE MICHIGAN ON TUESDAY...RAIN WILL BE LIKELY IN A CONCENTRATED
BAND OF ISENTROPIC LIFT EXTENDING SOUTHEAST FROM THE LOW CENTER.

ENERGY WILL TRANSFER TO A COASTAL LOW ON WEDNESDAY...LEAVING THE
AREA IN A BRISK AND COLDER NORTHWEST FLOW OF DECREASING MOISTURE AND
FORCING. THIS WILL BRING AN END TO STEADY RAIN AND SNOW...WITH
SCATTERED SNOW SHOWERS THEN LINGERING INTO THURSDAY. NORTHERN
LOCATIONS SEEM TO HAVE THE BEST CHANCE FOR LIGHT SNOW ACCUMULATIONS.

AFTER NEAR NORMAL HIGHS AROUND 40 ON SUNDAY...WARM ADVECTION AHEAD
OF THE LOW WILL ALLOW ABOVE NORMAL HIGHS IN THE 40S ON MONDAY AND
TUESDAY. EXPECT EARLY HIGHS NEAR 40 ON WEDNESDAY...DROPPING TO
BELOW NORMAL 30S UNDER COLD ADVECTION ON THURSDAY.

&&

.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
PERSISTENT MVFR CLOUDS ARE EXPECTED TO CONTINUE THROUGH THE TAF
PERIOD. A FEW BREAKS HAVE DEVELOPED IN THE CINCINNATI AREA...BUT
OVERNIGHT...THE LOW CLOUDS ARE EXPECTED TO MOVE BACK INTO THE
REGION. THESE CLOUDS ARE GENERALLY IN THE 1500-2000 FOOT
RANGE...WITH A FEW SPOTS AS HIGH AS 2500 FEET. PRECIPITATION
APPEARS TO BE UNLIKELY...BUT A FEW FLURRIES WILL STILL BE POSSIBLE
THIS EVENING.

AS LIGHT WINDS SHIFT FROM WNW TO NNW TOMORROW...THE CLOUD DECK IS
STILL EXPECTED TO REMAIN IN PLACE...THOUGH THERE IS SOME CHANCE OF
EROSION TO VFR CONDITIONS DURING THE AFTERNOON. THIS FORECAST WILL
MAINTAIN MVFR CEILINGS...THOUGH SHOWING A SLIGHT LIFTING INTO THE
2000-2500 FOOT RANGE.

OUTLOOK...MVFR CEILINGS MAY CONTINUE INTO FRIDAY. MVFR CEILINGS
AND VISIBILITIES ARE POSSIBLE ON SATURDAY.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

&&

$$
SYNOPSIS...HICKMAN
NEAR TERM...HATZOS/HICKMAN
SHORT TERM...HICKMAN
LONG TERM...CONIGLIO
AVIATION...HATZOS







AREA FORECAST DISCUSSION

NWS WILMINGTON OH

 624 PM EST THU DEC 18 2014

.SYNOPSIS...
A WEAKENING UPPER LEVEL DISTURBANCE MOVING THROUGH THE OHIO VALLEY
WILL RESULT IN A FEW SNOW FLURRIES OR SNOW SHOWERS THIS EVENING.
WEAK SURFACE HIGH PRESSURE WILL THEN PUSH SLOWLY EAST ACROSS THE
REGION THROUGH THE WEEKEND...LEADING TO PRIMARILY DRY CONDITIONS
AND NEAR NORMAL TEMPERATURES.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
UPR LVL S/WV WILL PASS EAST ACRS OUR REGION THROUGH THIS EVENING.
FORCING IS WEAK WITH MOST AREAS JUST SEEING A FEW FLURRIES. THERE
COULD BE A FEW SNOW SHOWERS WITH JUST A LIGHT DUSTING ALONG THE
I-70 CORRIDOR WHERE DEEPEST MOISTURE WILL INTERSECT WEAK FORCING.
LOW LEVEL CLOUDS WILL CONTINUE TO BE AN ISSUE AS THE RAP MODEL
SHOWS REGION STAYING PRETTY MUCH OVERCAST OVERNIGHT. LOWS WILL
DROP INTO THE LOWER AND MID 20S.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
WEAK SFC HIGH PRESSURE WILL SLOWLY BUILD INTO THE AREA ON FRIDAY.
DESPITE THIS FEATURE...IT LOOKS LIKE LOW LEVEL MOISTURE WILL HANG
AROUND AS IT BECOMES TRAPPED UNDERNEATH THE HIGH. WILL CONTINUE
WITH MAINLY CLOUDY SKIES. HIGHS WILL RANGE FROM THE LOWER TO MID
30S.

FOR FRIDAY NIGHT INTO SATURDAY...LATEST MODEL FORECASTS KEEP THE
AFFECTS OF AN UPR LVL S/WV TO OUR SOUTH WHILE SFC RIDGING REMAINS
IN PLACE. IT IS DIFFICULT TO KNOW IF THE LOW LEVEL CLOUDS WILL
ERODE DURING THIS TIME FRAME. HOWEVER...WITH AN INCREASE IN MID
AND HIGH LEVEL MOISTURE...IT WILL LIKELY REMAIN MOSTLY CLOUDY. IT
WILL BE A LITTLE WARMER ON SATURDAY WITH HIGHS IN THE MID AND
UPPER 30S.

BY SATURDAY NIGHT...HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS
THE GREAT LAKES AND OHIO VALLEY WHILE A WEAK UPR LVL S/WV PASSES
ACRS THE SOUTHERN GREAT LAKES. PARTLY CLOUDY SKIES ARE EXPECTED.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE CENTERED TO THE NORTHEAST WILL BRING DRY WEATHER ON
SUNDAY. INCREASING MOISTURE AND LIFT WELL AHEAD OF DEVELOPING LOW
PRESSURE MAY PRODUCE LIGHT RAIN AND SNOW ON MONDAY. AS THE LOW MOVES
TO LAKE MICHIGAN ON TUESDAY...RAIN WILL BE LIKELY IN A CONCENTRATED
BAND OF ISENTROPIC LIFT EXTENDING SOUTHEAST FROM THE LOW CENTER.

ENERGY WILL TRANSFER TO A COASTAL LOW ON WEDNESDAY...LEAVING THE
AREA IN A BRISK AND COLDER NORTHWEST FLOW OF DECREASING MOISTURE AND
FORCING. THIS WILL BRING AN END TO STEADY RAIN AND SNOW...WITH
SCATTERED SNOW SHOWERS THEN LINGERING INTO THURSDAY. NORTHERN
LOCATIONS SEEM TO HAVE THE BEST CHANCE FOR LIGHT SNOW ACCUMULATIONS.

AFTER NEAR NORMAL HIGHS AROUND 40 ON SUNDAY...WARM ADVECTION AHEAD
OF THE LOW WILL ALLOW ABOVE NORMAL HIGHS IN THE 40S ON MONDAY AND
TUESDAY. EXPECT EARLY HIGHS NEAR 40 ON WEDNESDAY...DROPPING TO
BELOW NORMAL 30S UNDER COLD ADVECTION ON THURSDAY.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
PERSISTENT MVFR CLOUDS ARE EXPECTED TO CONTINUE THROUGH THE TAF
PERIOD. A FEW BREAKS HAVE DEVELOPED IN THE CINCINNATI AREA...BUT
OVERNIGHT...THE LOW CLOUDS ARE EXPECTED TO MOVE BACK INTO THE
REGION. THESE CLOUDS ARE GENERALLY IN THE 1500-2000 FOOT
RANGE...WITH A FEW SPOTS AS HIGH AS 2500 FEET. PRECIPITATION
APPEARS TO BE UNLIKELY...BUT A FEW FLURRIES WILL STILL BE POSSIBLE
THIS EVENING.

AS LIGHT WINDS SHIFT FROM WNW TO NNW TOMORROW...THE CLOUD DECK IS
STILL EXPECTED TO REMAIN IN PLACE...THOUGH THERE IS SOME CHANCE OF
EROSION TO VFR CONDITIONS DURING THE AFTERNOON. THIS FORECAST WILL
MAINTAIN MVFR CEILINGS...THOUGH SHOWING A SLIGHT LIFTING INTO THE
2000-2500 FOOT RANGE.

OUTLOOK...MVFR CEILINGS MAY CONTINUE INTO FRIDAY. MVFR CEILINGS
AND VISIBILITIES ARE POSSIBLE ON SATURDAY.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

&&

$$
SYNOPSIS...HICKMAN
NEAR TERM...HICKMAN
SHORT TERM...HICKMAN
LONG TERM...CONIGLIO
AVIATION...HATZOS







AREA FORECAST DISCUSSION

NWS WILMINGTON OH

 551 PM EST WED DEC 17 2014

.SYNOPSIS...
WEAK HIGH PRESSURE WILL NOSE INTO THE REGION TONIGHT. HOWEVER
ABUNDANT LOW LEVEL MOISTURE WILL RESULT IN A CONTINUATION OF MAINLY
CLOUDY SKIES. A WEAK UPPER LEVEL DISTURBANCE COULD LEAD TO A FEW
FLURRIES THURSDAY AFTERNOON INTO THURSDAY NIGHT. HIGH PRESSURE WILL
BUILD BACK IN OFFERING DRY CONDITIONS AND NEAR SEASONABLE
TEMPERATURES FOR THE END OF THE WEEK.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
ELONGATED MID LEVEL LOW OVER THE GREAT LAKES TO SHIFT OFF INTO NEW
ENGLAND. A FEW ISOLD LINGERING FLURRIES IN THE LOW LEVEL CAA WILL
COME TO AN END EARLY. MID LEVEL FLOW BECOMES BRIEFLY NW AHEAD OF AN
UPSTREAM S/W RIDGE. SFC HIGH PRESSURE TO NOSE INTO THE OHIO VALLEY
OVERNIGHT IN REGION OF H5 CONFLUENCE. 12Z ILN SOUNDING SHOWS LOW
LEVEL MOISTURE TRAPPED BELOW AN INVERSION AROUND 850 MB. GFS IS
AGGRESSIVE WITH CLEARING LOW LEVEL MOISTURE. NAM AND RAP SOLNS KEEP
CLOUDS OVERNIGHT. WILL ALLOW A FEW BREAKS OVER THE SOUTH/SOUTHWEST
BUT LEAN TOWARD THE NAM/RAP SOLN. TEMPERATURES WILL BE CLOSE TO
NORMAL WITH LOWS FROM THE MID 20S NORTH TO THE UPPER 20S SOUTH.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
MID LEVEL S/W TO RIPPLE QUICKLY EAST FROM THE CENTRAL PLAINS
THROUGH THE OHIO VALLEY THURSDAY. THIS WEAK SHORTWAVE IS DAMPENING
AND CROSSING OVER THE SFC RIDGE. FORCING IS VERY WEAK AND IN THE
MID LEVELS. A FLURRY OR SPRINKLE IS NOT OUT OF THE QUESTION FROM A
MID DECK. FLURRIES/SPRINKLES ALREADY IN THE FORECAST...SO WILL
CONTINUE. TEMPERATURES WILL BE BELOW NORMAL WITH HIGHS FROM THE
LOWER 30S NORTH TO THE MID/UPR 30S SOUTH.

IN WESTERLY MID LEVEL FLOW REGIME...SFC HIGH PRESSURE TO BUILD
ACRS THE GREAT LAKES/OHIO VALLEY THURSDAY NIGHT/FRIDAY. A FEW
FLURRIES WILL REMAIN POSSIBLE THURSDAY EVENING BUT WILL COME TO AN
END WITH THE PASSAGE OF THE S/W. AS THE HIGH BUILD NOSES IN
EXPECT SOME PARTIAL CLEARING THURSDAY NIGHT. LOWS EXPECTED TO
RANGE FROM THE MID 20S NORTH TO THE UPPER 20S SOUTH.

EXPECT TO SEE MORE SUNSHINE FRIDAY WITH AN INCREASE IN HIGH LEVEL
MOISTURE LATE IN THE DAY. FRIDAYS HIGHS FROM THE MID 30S NORTH TO
NEAR 40 SOUTH.

CLOUDS WILL THICKEN AND INCREASE FRIDAY NIGHT AS SYSTEM APPROACHES
FROM THE SOUTHWEST. WILL KEEP FCST DRY FRIDAY NIGHT AS CONSENSUS
DOES NOT BRING MOISTURE IN UNTIL SATURDAY. LOWS FRIDAY NIGHT TO
RANGE FROM THE UPPER 20S NORTH TO THE LOWER 30S FAR SOUTH.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
FOR SATURDAY...LOOKS LIKE WE COULD SEE SNOW CHANGING TO RAIN AS LOW
PRESSURE TRAVELS NEAR THE GULF COAST. THE LOW HAS TRENDED FARTHER TO
THE SOUTH SO CUT BACK ON POPS AND PRECIP AMOUNTS. HIGH PRESSURE AND
A COOL AIRMASS SHOULD ALLOW DRY WEATHER ON SUNDAY. LIGHT PRECIP WILL
BE POSSIBLE MONDAY EXTENDING FROM A TROUGH ALONG THE EAST COAST.

WE MAY BEGIN TO FEEL THE EFFECTS OF A POWERFUL LOW PRESSURE SYSTEM
ON TUESDAY. HAVE LESS THAN AVERAGE AMOUNT OF CONFIDENCE DUE TO MODEL
DIFFERENCES FROM RUN TO RUN. AT THIS POINT IT APPEARS THE LOW WILL
DEVELOP OVER THE SOUTHERN PLAINS ON TUESDAY...BEFORE LIFTING THROUGH
OHIO TO THE GREAT LAKES ON WEDNESDAY. THE LOW MAY FEATURE A VERY
TIGHT PRESSURE GRADIENT SURROUNDING ITS DEEP CENTER...PRODUCING
STRONG WINDS. COPIOUS MOISTURE FEEDING FROM THE TROPICS AND FROM THE
ATLANTIC OCEAN COULD ADVECT AROUND THE LOW. CURRENT TEMPERATURE
FORECAST ALLOWS RAIN TUESDAY INTO WEDNESDAY...CHANGING TO SNOW LATER
WEDNESDAY AS COLDER AIR WRAPS IN BEHIND THE LOW.

TEMPERATURES WILL BE RELATIVELY CLOSE TO NORMAL FOR THE MOST PART.
HIGHS ARE FORECAST TO BE IN THE MID AND UPPER 30S SATURDAY...THEN A
COUPLE DEGREES WARMER FOR SUNDAY AND MONDAY UNDER NEUTRAL TO WEAK
WARM ADVECTION. READINGS ON TUESDAY AND WEDNESDAY WILL BE DEPENDENT
ON THE POSITION OF THE ANTICIPATED STRONG LOW. WARM ADVECTION AHEAD
OF THE LOW COULD BRING HIGHS UP INTO THE MID 40S ON TUESDAY...OR
EVEN HIGHER IF THE WARMER MEX GUIDANCE VERIFIES. HIGHS COULD SLIP TO
AROUND 40 ON WEDNESDAY IN COLD ADVECTION BEHIND THE LOW.

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
A PERSISTENT MVFR CLOUD DECK IS LIKELY TO REMAIN IN PLACE ACROSS
THE TAF SITES THROUGH THE ENTIRE FORECAST PERIOD. THESE CLOUDS ARE
GENERALLY LOCATED BETWEEN 1200 AND 2200 FEET ABOVE GROUND
LEVEL...AND LITTLE CHANGE IN HEIGHT IS EXPECTED...THOUGH A SLIGHT
LIFTING IS POSSIBLE TOMORROW. THIS CLOUD DECK HAS SHOWN SOME SIGNS
OF EROSION FROM THE SOUTH...BUT WHILE IT APPEARS POSSIBLE THAT
BREAKS IN THE OVERCAST COULD WORK INTO THE CINCINNATI AREA
OVERNIGHT...IT IS MORE LIKELY THAT THIS EROSION WILL SLOW OR STOP
IN THE NEXT FEW HOURS.

WNW WINDS OF AROUND 10 KNOTS WILL DIMINISH OVERNIGHT...AND REMAIN
UNDER 10 KNOTS TOMORROW. A FEW FLURRIES WILL BE POSSIBLE...MAINLY
AFTER 18Z...WITH NO EXPECTED IMPACTS TO AVIATION.

OUTLOOK...MVFR CEILINGS MAY CONTINUE INTO FRIDAY. MVFR CEILINGS AND
VISIBILITIES ARE POSSIBLE ON SATURDAY.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

&&

$$
SYNOPSIS...AR
NEAR TERM...AR
SHORT TERM...AR
LONG TERM...CONIGLIO
AVIATION...HATZOS






AREA FORECAST DISCUSSION

NWS WILMINGTON OH

 428 PM EST WED DEC 17 2014

.SYNOPSIS...
WEAK HIGH PRESSURE WILL NOSE INTO THE REGION TONIGHT. HOWEVER
ABUNDANT LOW LEVEL MOISTURE WILL RESULT IN A CONTINUATION OF MAINLY
CLOUDY SKIES. A WEAK UPPER LEVEL DISTURBANCE COULD LEAD TO A FEW
FLURRIES THURSDAY AFTERNOON INTO THURSDAY NIGHT. HIGH PRESSURE WILL
BUILD BACK IN OFFERING DRY CONDITIONS AND NEAR SEASONABLE
TEMPERATURES FOR THE END OF THE WEEK.


&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
ELONGATED MID LEVEL LOW OVER THE GREAT LAKES TO SHIFT OFF INTO NEW
ENGLAND. A FEW ISOLD LINGERING FLURRIES IN THE LOW LEVEL CAA WILL
COME TO AN END EARLY. MID LEVEL FLOW BECOMES BRIEFLY NW AHEAD OF AN
UPSTREAM S/W RIDGE. SFC HIGH PRESSURE TO NOSE INTO THE OHIO VALLEY
OVERNIGHT IN REGION OF H5 CONFLUENCE. 12Z ILN SOUNDING SHOWS LOW
LEVEL MOISTURE TRAPPED BELOW AN INVERSION AROUND 850 MB. GFS IS
AGGRESSIVE WITH CLEARING LOW LEVEL MOISTURE. NAM AND RAP SOLNS KEEP
CLOUDS OVERNIGHT. WILL ALLOW A FEW BREAKS OVER THE SOUTH/SOUTHWEST
BUT LEAN TOWARD THE NAM/RAP SOLN. TEMPERATURES WILL BE CLOSE TO
NORMAL WITH LOWS FROM THE MID 20S NORTH TO THE UPPER 20S SOUTH.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
MID LEVEL S/W TO RIPPLE QUICKLY EAST FROM THE CENTRAL PLAINS
THROUGH THE OHIO VALLEY THURSDAY. THIS WEAK SHORTWAVE IS DAMPENING
AND CROSSING OVER THE SFC RIDGE. FORCING IS VERY WEAK AND IN THE
MID LEVELS. A FLURRY OR SPRINKLE IS NOT OUT OF THE QUESTION FROM A
MID DECK. FLURRIES/SPRINKLES ALREADY IN THE FORECAST...SO WILL
CONTINUE. TEMPERATURES WILL BE BELOW NORMAL WITH HIGHS FROM THE
LOWER 30S NORTH TO THE MID/UPR 30S SOUTH.

IN WESTERLY MID LEVEL FLOW REGIME...SFC HIGH PRESSURE TO BUILD
ACRS THE GREAT LAKES/OHIO VALLEY THURSDAY NIGHT/FRIDAY. A FEW
FLURRIES WILL REMAIN POSSIBLE THURSDAY EVENING BUT WILL COME TO AN
END WITH THE PASSAGE OF THE S/W. AS THE HIGH BUILD NOSES IN
EXPECT SOME PARTIAL CLEARING THURSDAY NIGHT. LOWS EXPECTED TO
RANGE FROM THE MID 20S NORTH TO THE UPPER 20S SOUTH.

EXPECT TO SEE MORE SUNSHINE FRIDAY WITH AN INCREASE IN HIGH LEVEL
MOISTURE LATE IN THE DAY. FRIDAYS HIGHS FROM THE MID 30S NORTH TO
NEAR 40 SOUTH.

CLOUDS WILL THICKEN AND INCREASE FRIDAY NIGHT AS SYSTEM APPROACHES
FROM THE SOUTHWEST. WILL KEEP FCST DRY FRIDAY NIGHT AS CONSENSUS
DOES NOT BRING MOISTURE IN UNTIL SATURDAY. LOWS FRIDAY NIGHT TO
RANGE FROM THE UPPER 20S NORTH TO THE LOWER 30S FAR SOUTH.


&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
FOR SATURDAY...LOOKS LIKE WE COULD SEE SNOW CHANGING TO RAIN AS LOW
PRESSURE TRAVELS NEAR THE GULF COAST. THE LOW HAS TRENDED FARTHER TO
THE SOUTH SO CUT BACK ON POPS AND PRECIP AMOUNTS. HIGH PRESSURE AND
A COOL AIRMASS SHOULD ALLOW DRY WEATHER ON SUNDAY. LIGHT PRECIP WILL
BE POSSIBLE MONDAY EXTENDING FROM A TROUGH ALONG THE EAST COAST.

WE MAY BEGIN TO FEEL THE EFFECTS OF A POWERFUL LOW PRESSURE SYSTEM
ON TUESDAY. HAVE LESS THAN AVERAGE AMOUNT OF CONFIDENCE DUE TO MODEL
DIFFERENCES FROM RUN TO RUN. AT THIS POINT IT APPEARS THE LOW WILL
DEVELOP OVER THE SOUTHERN PLAINS ON TUESDAY...BEFORE LIFTING THROUGH
OHIO TO THE GREAT LAKES ON WEDNESDAY. THE LOW MAY FEATURE A VERY
TIGHT PRESSURE GRADIENT SURROUNDING ITS DEEP CENTER...PRODUCING
STRONG WINDS. COPIOUS MOISTURE FEEDING FROM THE TROPICS AND FROM THE
ATLANTIC OCEAN COULD ADVECT AROUND THE LOW. CURRENT TEMPERATURE
FORECAST ALLOWS RAIN TUESDAY INTO WEDNESDAY...CHANGING TO SNOW LATER
WEDNESDAY AS COLDER AIR WRAPS IN BEHIND THE LOW.

TEMPERATURES WILL BE RELATIVELY CLOSE TO NORMAL FOR THE MOST PART.
HIGHS ARE FORECAST TO BE IN THE MID AND UPPER 30S SATURDAY...THEN A
COUPLE DEGREES WARMER FOR SUNDAY AND MONDAY UNDER NEUTRAL TO WEAK
WARM ADVECTION. READINGS ON TUESDAY AND WEDNESDAY WILL BE DEPENDENT
ON THE POSITION OF THE ANTICIPATED STRONG LOW. WARM ADVECTION AHEAD
OF THE LOW COULD BRING HIGHS UP INTO THE MID 40S ON TUESDAY...OR
EVEN HIGHER IF THE WARMER MEX GUIDANCE VERIFIES. HIGHS COULD SLIP TO
AROUND 40 ON WEDNESDAY IN COLD ADVECTION BEHIND THE LOW.

&&

.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
SURFACE HIGH PRESSURE LOCATED TO OUR WEST AND NORTHWEST WILL BUILD
INTO OUR REGION TONIGHT. DESPITE THIS HIGH...LOW LEVEL MOISTURE
REMAINS TRAPPED UNDERNEATH A SUBSIDENCE INVERSION. THIS HAS
RESULTED IN A PRETTY SOLID STRATOCUMULUS DECK BETWEEN 1500-2500
FEET. MODELS CONTINUE TO STRUGGLE AS TO WHETHER THESE CLOUDS WILL
THIN AND/OR ERODE THROUGH THE PERIOD. HAVE GONE PESSIMISTIC AT
THIS POINT WHICH IS TO KEEP MVFR CEILINGS GOING THROUGH THE TAF
PERIOD. ON THURSDAY...SURFACE HIGH PRESSURE WILL REMAIN OVER THE
AREA. A WEAK DISTURBANCE ALOFT IS FORECAST TO PASS EAST ACROSS THE
OHIO VALLEY. DEEPER MOISTURE AND FORCING SHOULD REMAIN TO OUR
SOUTHWEST WHILE THE FEATURE WEAKENS AS IT AFFECTS OUR AREA. IT
LOOKS LIKE THE ONLY THREAT FOR PRECIPITATION WOULD BE A FEW
FLURRIES.

OUTLOOK...MVFR CEILINGS MAY LINGER INTO FRIDAY. MVFR CEILINGS AND
VISIBILITIES POSSIBLE SATURDAY.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

&&

$$
SYNOPSIS...AR
NEAR TERM...AR
SHORT TERM...AR
LONG TERM...CONIGLIO
AVIATION...HICKMAN






AREA FORECAST DISCUSSION

NWS WILMINGTON OH

 958 AM EST WED DEC 17 2014

.SYNOPSIS...
WEAK HIGH PRESSURE WILL BUILD INTO THE REGION THROUGH TONIGHT BUT
ABUNDANT MOISTURE TRAPPED IN THE LOWER LEVELS OF THE ATMOSPHERE
WILL RESULT IN A CONTINUATION OF CLOUDY SKIES. A WEAK UPPER LEVEL
DISTURBANCE COULD LEAD TO A FEW FLURRIES THURSDAY AFTERNOON INTO
THURSDAY NIGHT. A BETTER CHANCE OF RAIN AND SNOW WILL MOVE INTO
THE REGION ON SATURDAY AS A LOW PRESSURE SYSTEM MOVES THROUGH THE
TENNESSEE VALLEY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
PATCHY -DZ/-FZDZ/-SN HAS PRETTY MUCH ENDED ACROSS OUR REGION THIS
MORNING AS SHALLOW STEEP LOW LEVEL LAPSE RATES AND SLIGHTLY DEEPER
MOISTURE UP TO 850 MB IS CONTINUE TO EXIT EAST. LOW STRATOCUMULUS
DECK STRETCHES BACK TO THE MS RIVER VALLEY. WITH THE SHALLOW
MOISTURE TRAPPED UNDERNEATH A SUBSIDENCE INVERSION...THERE DOES
NOT APPEAR MUCH HOPE OF SEEING ANY CLOUD EROSION IN OUR AREA. WILL
CONTINUE WITH CLOUDY SKIES THROUGH THE DAY. TEMPERATURES WILL NOT
WARM MUCH FROM CURRENT MID MORNING READINGS. HIGHS SHOULD RANGE
FROM THE LOWER 30S NW TO PERHAPS THE MID/UPPER 30S FAR SOUTHEAST.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
BASED ON THE UPSTREAM CLOUD COVER AND CONTINUED CYCLONIC
FLOW...SEE NO REASON TO STRAY FROM THE MUCH MORE CLOUDY NAM
SOLUTION THAT KEEPS ABUNDANT LOW LEVEL MOISTURE IN PLACE TONIGHT
INTO THURSDAY. THE LOW LEVELS WILL BEGIN TO DRY OUT THURSDAY AFTERNOON
INTO THURSDAY NIGHT AS A WEAKENING MID LEVEL SHORTWAVE MOVES OUT
OF THE MID MISSISSIPPI VALLEY. FORCING IS PRETTY WEAK BY THE TIME
IT MAKES IT INTO OUR AREA AND WITH ONLY SOME LIMITED
MOISTURE...THINK WE MAY JUST SEE A FEW FLURRIES WITH THIS.
BOUNDARY LAYER TEMPERATURES APPEAR WARM ENOUGH ACROSS THE FAR
SOUTH THURSDAY AFTERNOON TO ALLOW FOR A FEW SPRINKLES TO MIX IN
WITH ANY FLURRY ACTIVITY. EXPECT HIGHS ON THURSDAY RANGING FROM THE
LOWER 30S NORTH TO MID 30S SOUTH...INCREASING INTO THE MID TO
UPPER 30S BY FRIDAY.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
HIGH PRESSURE AND DRY CONDITIONS WILL START OUT THE LONG TERM
PERIOD.  THE NEXT SYSTEM WILL BEGIN TO APPROACH THE AREA LATE FRIDAY
NIGHT AND INTO THE DAY ON SATURDAY BEFORE TAPERING OFF SATURDAY
NIGHT.  PRECIPITATION WILL GENERALLY BE IN THE FORM OF LIGHT SNOW
ACROSS THE NW HALF OF THE FA.  PRECIPITATION IS EXPECTED TO START
OFF AS SNOW ACROSS THE SE HALF OF THE FA HOWEVER SOME RAIN IS
EXPECTED TO MIX IN DURING THE DAY BEFORE TRANSITIONING BACK TO LIGHT
SNOW.

HIGH PRESSURE WILL THEN WORK BACK INTO THE AREA FOR SUNDAY AND
MONDAY.  THE NEXT SYSTEM WILL BEGIN TO WORK INTO THE AREA FOR
TUESDAY.  MODELS WERE IN SOMEWHAT DECENT AGREEMENT WITH THIS FEATURE
HOWEVER THE 12Z ECMWF SOLUTION IS NOW SLOWER AND MORE ROBUST.  DID
NOT WANT TO JUMP ON THIS NEW SOLUTION QUITE YET AND WENT WITH MORE
OF A MODEL BLEND FOR TUESDAY.  A MIX OF RAIN AND SNOW ARE EXPECTED
HOWEVER AS COLDER AIR BEGINS TO MOVE INTO THE AREA PRECIPITATION
LOOKS TO CHANGE OVER TO ALL SNOW SHOWERS DURING THE TUESDAY NIGHT
INTO WEDNESDAY TIME PERIOD.

&&

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
MVFR LOW CLOUDS WILL PREVAIL THROUGH THE TAF PERIOD. THERE
CONTINUES TO BE SIGNIFICANT DISCREPANCIES IN GUIDANCE CONCERNING
CLOUDS POTENTIALLY CLEARING EARLY THIS AFTERNOON. BUT BASED ON
WHAT HAS BEEN OCCURRING UPSTREAM FROM SURFACE OBSERVATIONS AND
SATELLITE IMAGERY HAVE OPTED TO KEEP FORECAST PESSIMISTIC AND GO
WITH THE NAM AND RAP SOLUTIONS. THERE IS A POSSIBILITY FOR A BRIEF
PERIOD OF IFR CONDS EARLY IN THE TAF PERIOD ASSOCIATE WITH VSBYS
IN SNOW SHOWERS. THESE SNOW SHOWERS CONTINUE TO DEVELOP IN
RESPONSE TO THE LOW LEVEL CONVERGENCE ASSOCIATED WITH THE CYCLONIC
FLOW OVER THE AREA AND SHOULD MOVE TO THE EAST OF THE TERMINAL BY
LATE MORNING/EARLY AFTERNOON.

AS THE CYCLONIC FLOW OVER THE AREA WEAKEN DURING THE DAY WEST
WINDS WILL SLOWLY DECREASE THROUGH TODAY AND TONIGHT SINCE THE INFLUENCE
OF THE LOW WILL BE SLOW TO MOVE AWAY FROM THE FORECAST AREA.

OUTLOOK...MVFR CEILINGS EARLY THURSDAY MORNING. MVFR CEILINGS AND
VISIBILITIES POSSIBLE FRIDAY NIGHT INTO SATURDAY NIGHT.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

&&

$$
SYNOPSIS...JGL
NEAR TERM...HICKMAN
SHORT TERM...JGL
LONG TERM...NOVAK
AVIATION...HAYDU






AREA FORECAST DISCUSSION

NWS WILMINGTON OH

 654 AM EST WED DEC 17 2014

.SYNOPSIS...
WEAK HIGH PRESSURE WILL BUILD INTO THE REGION THROUGH TONIGHT BUT
ABUNDANT MOISTURE TRAPPED IN THE LOWER LEVELS OF THE ATMOSPHERE
WILL RESULT IN A CONTINUATION OF CLOUDY SKIES. A WEAK UPPER LEVEL
DISTURBANCE COULD LEAD TO A FEW FLURRIES THURSDAY AFTERNOON INTO
THURSDAY NIGHT. A BETTER CHANCE OF RAIN AND SNOW WILL MOVE INTO
THE REGION ON SATURDAY AS A LOW PRESSURE SYSTEM MOVES THROUGH THE
TENNESSEE VALLEY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SOME SLIGHTLY DEEPER MOISTURE IS RESULTING IN SOME LINGERING RAIN
AND SNOW SHOWERS ACROSS EASTERN PORTIONS OF OUR FA EARLY THIS
MORNING. MEANWHILE...PCPN HAS TRANSITIONED TO MORE OF A DRIZZLE OR
FLURRY ACROSS WESTERN PORTIONS OF OUR FA. THE LATEST RAP DOES
ALLOW FOR THE SURFACE TO 2 KM LAYER TO CONTINUE TO DRY OUT FROM
WEST TO EAST ACROSS THE AREA THROUGH MID MORNING. THIS SHOULD
ALLOW FOR THE DRIZZLE/FLURRY ACTIVITY TO GRADUALLY TAPER OFF FROM
THE WEST. IN THE LOW LEVEL CAA PATTERN...TEMPERATURES HAVE BEEN
STEADILY FALLING THIS MORNING WITH READINGS NOW AT OR A BIT BELOW
FREEZING ACROSS OUR NORTHWEST. AS A RESULT...THERE COULD BE SOME
AREAS OF FREEZING DRIZZLE THIS MORNING BEFORE THE PCPN TAPERS
OFF...ESPECIALLY ACROSS OUR NORTHERN AREAS. WITH THE WARM
TEMPERATURES OF THE PAST FEW DAYS...ROAD SURFACES ARE STILL
RUNNING SEVERAL DEGREES ABOVE FREEZING. THAT BEING SAID..ELEVATED
SURFACES AND UNTREATED BRIDGES/OVERPASSES COULD SEE A LIGHT ICE
ACCUMULATION AND WILL GO AHEAD AND COVER THE THREAT WITH AN SPS.
OTHERWISE...EXPECT CLOUDY SKIES TO CONTINUE THROUGH THE REST OF
THE AFTERNOON IN CONTINUED CYCLONIC LOW LEVEL FLOW. THE
COMBINATION OF CLOUDS AND CAA WILL RESULT IN FAIRLY STEADY TEMPS
TODAY IN THE LOW TO MID 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
BASED ON THE UPSTREAM CLOUD COVER AND CONTINUED CYCLONIC
FLOW...SEE NO REASON TO STRAY FROM THE MUCH MORE CLOUDY NAM
SOLUTION THAT KEEPS ABUNDANT LOW LEVEL MOISTURE IN PLACE TONIGHT
INTO THURSDAY. THE LOW LEVELS WILL BEGIN TO DRY OUT THURSDAY AFTERNOON
INTO THURSDAY NIGHT AS A WEAKENING MID LEVEL SHORTWAVE MOVES OUT
OF THE MID MISSISSIPPI VALLEY. FORCING IS PRETTY WEAK BY THE TIME
IT MAKES IT INTO OUR AREA AND WITH ONLY SOME LIMITED
MOISTURE...THINK WE MAY JUST SEE A FEW FLURRIES WITH THIS.
BOUNDARY LAYER TEMPERATURES APPEAR WARM ENOUGH ACROSS THE FAR
SOUTH THURSDAY AFTERNOON TO ALLOW FOR A FEW SPRINKLES TO MIX IN
WITH ANY FLURRY ACTIVITY. EXPECT HIGHS ON THURSDAY RANGING FROM THE
LOWER 30S NORTH TO MID 30S SOUTH...INCREASING INTO THE MID TO
UPPER 30S BY FRIDAY.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
HIGH PRESSURE AND DRY CONDITIONS WILL START OUT THE LONG TERM
PERIOD.  THE NEXT SYSTEM WILL BEGIN TO APPROACH THE AREA LATE FRIDAY
NIGHT AND INTO THE DAY ON SATURDAY BEFORE TAPERING OFF SATURDAY
NIGHT.  PRECIPITATION WILL GENERALLY BE IN THE FORM OF LIGHT SNOW
ACROSS THE NW HALF OF THE FA.  PRECIPITATION IS EXPECTED TO START
OFF AS SNOW ACROSS THE SE HALF OF THE FA HOWEVER SOME RAIN IS
EXPECTED TO MIX IN DURING THE DAY BEFORE TRANSITIONING BACK TO LIGHT
SNOW.

HIGH PRESSURE WILL THEN WORK BACK INTO THE AREA FOR SUNDAY AND
MONDAY.  THE NEXT SYSTEM WILL BEGIN TO WORK INTO THE AREA FOR
TUESDAY.  MODELS WERE IN SOMEWHAT DECENT AGREEMENT WITH THIS FEATURE
HOWEVER THE 12Z ECMWF SOLUTION IS NOW SLOWER AND MORE ROBUST.  DID
NOT WANT TO JUMP ON THIS NEW SOLUTION QUITE YET AND WENT WITH MORE
OF A MODEL BLEND FOR TUESDAY.  A MIX OF RAIN AND SNOW ARE EXPECTED
HOWEVER AS COLDER AIR BEGINS TO MOVE INTO THE AREA PRECIPITATION
LOOKS TO CHANGE OVER TO ALL SNOW SHOWERS DURING THE TUESDAY NIGHT
INTO WEDNESDAY TIME PERIOD.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
MVFR LOW CLOUDS WILL PREVAIL THROUGH THE TAF PERIOD. THERE
CONTINUES TO BE SIGNIFICANT DISCREPANCIES IN GUIDANCE CONCERNING
CLOUDS POTENTIALLY CLEARING EARLY THIS AFTERNOON. BUT BASED ON
WHAT HAS BEEN OCCURRING UPSTREAM FROM SURFACE OBSERVATIONS AND
SATELLITE IMAGERY HAVE OPTED TO KEEP FORECAST PESSIMISTIC AND GO
WITH THE NAM AND RAP SOLUTIONS. THERE IS A POSSIBILITY FOR A BRIEF
PERIOD OF IFR CONDS EARLY IN THE TAF PERIOD ASSOCIATE WITH VSBYS
IN SNOW SHOWERS. THESE SNOW SHOWERS CONTINUE TO DEVELOP IN
RESPONSE TO THE LOW LEVEL CONVERGENCE ASSOCIATED WITH THE CYCLONIC
FLOW OVER THE AREA AND SHOULD MOVE TO THE EAST OF THE TERMINAL BY
LATE MORNING/EARLY AFTERNOON.

AS THE CYCLONIC FLOW OVER THE AREA WEAKEN DURING THE DAY WEST
WINDS WILL SLOWLY DECREASE THROUGH TODAY AND TONIGHT SINCE THE INFLUENCE
OF THE LOW WILL BE SLOW TO MOVE AWAY FROM THE FORECAST AREA.

OUTLOOK...MVFR CEILINGS EARLY THURSDAY MORNING. MVFR CEILINGS AND
VISIBILITIES POSSIBLE FRIDAY NIGHT INTO SATURDAY NIGHT.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

&&

$$
SYNOPSIS...JGL
NEAR TERM...JGL
SHORT TERM...JGL
LONG TERM...NOVAK
AVIATION...HAYDU






AREA FORECAST DISCUSSION

NWS CHARLESTON WV

 536 AM EST WED DEC 17 2014

.SYNOPSIS...
LOW LEVEL MOISTURE THROUGH THURSDAY NIGHT. HIGH PRESSURE FRIDAY.
LOW PRESSURE SYSTEM FOR THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
LOWERED THE TEMPERATURES TODAY A COUPLE DEGREES ACROSS THE BOARD.
NO CHANGES OTHERWISE.

PREVIOUS DISCUSSION...
LOOKS LIKE WE WILL BE REVERTING TO A SIMILAR SET UP FROM LATE
LAST WEEK WITH TRAPPED MOISTURE IN THE BOUNDARY LAYER UNDER
ANOTHER MASSIVE INVERSION WITH AROUND 60-90MB DEPTH. THIS IS THE
BIGGEST CHANGE TO THE FORECAST WITH GOING 100 SKY COVER ACROSS THE
BOARD THROUGH 12Z THURSDAY. FOLLOWING THE HRRR BRINGS THE CHANCES
FOR MEASURABLE PRECIPITATION TO AN END BY 00Z TONIGHT. CARRY
DRIZZLE/FREEZING DRIZZLE UNTIL 18Z TODAY AND WILL NEED TO MONITOR
THIS TO SEE IF THIS NEEDS TO GO LONGER IN THE FORECAST.

COLD AIR ADVECTION CONTINUING INTO THE OVERNIGHT BRINGS TEMPERATURES
BACK DOWN BELOW FREEZING AREA WIDE. WIND STAYING UP SHOULD KEEP ANY
POTENTIAL FOR FREEZING FOG AT BAY.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY/...
BEFORE THE ADVERTISED STORM SYSTEM FOR THIS WEEKEND...OF WHICH
LITTLE HAS CHANGED IN THAT FORECAST...THE PATTERN ALOFT WILL BE
ZONAL WITH A SERIES OF WEAK UPPER DISTURBANCES MOVING ACROSS THE
AREA. THESE WILL KEEP CONSIDERABLE CLOUDINESS THURSDAY AND
FRIDAY...BUT NO PRECIP ADDED AS MOISTURE IS LIMITED AND THE
DISTURBANCES WILL BE WEAKENING AS THEY MOVE ACROSS. TEMPERATURES WILL
BE NEAR NORMAL FOR THIS TIME OF YEAR.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ACTIVE WEATHER IN THE LONG TERM PERIOD. PERIOD STARTS OUT WITH A
SPLIT UPPER FLOW PATTERN ACROSS THE U.S...WITH A LOW PRESSURE SYSTEM
IN THE SOUTHERN STREAM MOVING EAST ACROSS THE SOUTHEASTERN UNITED
STATES FRIDAY NIGHT INTO SATURDAY...WITH A SHORTWAVE TROUGH IN THE
NORTHERN STREAM PUSHING EAST ACROSS THE OHIO VALLEY...BRINGING A
REINFORCING SHOT OF COLD AIR INTO THE REGION. MODELS ARE STARTING TO
COME INTO BETTER AGREEMENT WITH THE TRACK OF THE LOW...BUT ECMWF IS
DEEPER...AND MORE PROGRESSIVE WITH NORTHERN STREAM SHORTWAVE...THUS
RESULTING IN A COLDER SOLUTION. DEPENDING ON WHICH SOLUN PANS
OUT...COULD SEE MORE OF A WINTRY MIX...AS WITH THE GFS SOLUN...OR A
MAINLY SNOW...WITH POSSIBLY BRIEF RAIN/SNOW MIX ACROSS
LOWLANDS...WITH THE ECMWF SOLUN. HAVE TRENDED THE FORECAST TOWARDS
HPC...WHICH TENDS TO FAVOR WARMER SOLUN. THUS...EXPECTING A WINTRY
MIX TO DEVELOP ACROSS THE AREA FRIDAY NIGHT/SATURDAY...BEFORE
TRANSITIONING TO MAINLY RAIN ACROSS THE LOWLANDS SATURDAY...THEN
BACK TO SNOW OR A MIX SATURDAY NIGHT. ITS POSSIBLE WINTER WEATHER
HEADLINES MAY BE NEEDED DURING THIS PERIOD.

HIGH PRESSURE WILL BUILD IN BEHIND THE SYSTEM FOR EARLY NEXT
WEEK...FOR A BRIEF BREAK IN THE PRECIPITATION...BEFORE ANOTHER
SYSTEM MOVES IN TOWARDS MID WEEK.

&&

.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
TEETERING ON THE MVFR/IFR CEILING THRESHOLD FOR A FEW HOURS THIS
MORNING WHICH WILL TAKE AWAY FROM THE CONFIDENCE IN THIS ISSUANCE
JUST A TOUCH. LOW LEVEL MOISTURE SOCKED INTO PLACE FOR THE TAF
PERIOD UNDER A STRONG DEVELOPING INVERSION ABOVE THE BOUNDARY
LAYER. AS A RESULT...RESTRICTIONS THROUGH THE PERIOD EXPECTED WITH
LOW CEILINGS IN PLACE. WINDS WILL KEEP ANY VISIBILITY ISSUES FROM
OCCURRING THROUGH 12Z THURSDAY. SOME MIXING TODAY COULD BUMP THE
CEILINGS UP OVER 2KFT FOR A PERIOD THIS AFTERNOON ALONG THE OHIO
RIVER.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z THURSDAY...

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: IFR MAY NOT DEVELOP AROUND DAWN. MAY SEE
BRIEF VFR AT PKB AND HTS THIS AFTERNOON.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH:   TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW:    TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

UTC 1HRLY       11   12   13   14   15   16   17   18   19   20   21   22
EST 1HRLY       06   07   08   09   10   11   12   13   14   15   16   17
CRW CONSISTENCY  H    M    M    M    M    H    H    H    M    M    M    M
HTS CONSISTENCY  H    H    M    M    M    H    H    H    M    M    M    M
BKW CONSISTENCY  M    M    H    H    H    H    H    M    M    M    M    M
EKN CONSISTENCY  L    L    H    H    H    H    H    H    H    H    H    H
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    M    M    M
CKB CONSISTENCY  H    H    H    M    M    H    H    H    H    H    H    H

AFTER 12Z THURSDAY...
IFR POSSIBLE IN WINTRY MIX SATURDAY INTO SUNDAY.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

&&

$$
SYNOPSIS...JMV/26
NEAR TERM...26
SHORT TERM...JMV
LONG TERM...SL
AVIATION...26








AREA FORECAST DISCUSSION

NWS WILMINGTON OH

 406 AM EST WED DEC 17 2014

.SYNOPSIS...
WEAK HIGH PRESSURE WILL BUILD INTO THE REGION THROUGH TONIGHT BUT
ABUNDANT MOISTURE TRAPPED IN THE LOWER LEVELS OF THE ATMOSPHERE
WILL RESULT IN A CONTINUATION OF CLOUDY SKIES. A WEAK UPPER LEVEL
DISTURBANCE COULD LEAD TO A FEW FLURRIES THURSDAY AFTERNOON INTO
THURSDAY NIGHT. A BETTER CHANCE OF RAIN AND SNOW WILL MOVE INTO
THE REGION ON SATURDAY AS A LOW PRESSURE SYSTEM MOVES THROUGH THE
TENNESSEE VALLEY.
&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SOME SLIGHTLY DEEPER MOISTURE IS RESULTING IN SOME LINGERING RAIN
AND SNOW SHOWERS ACROSS EASTERN PORTIONS OF OUR FA EARLY THIS
MORNING. MEANWHILE...PCPN HAS TRANSITIONED TO MORE OF A DRIZZLE OR
FLURRY ACROSS WESTERN PORTIONS OF OUR FA. THE LATEST RAP DOES
ALLOW FOR THE SURFACE TO 2 KM LAYER TO CONTINUE TO DRY OUT FROM
WEST TO EAST ACROSS THE AREA THROUGH MID MORNING. THIS SHOULD
ALLOW FOR THE DRIZZLE/FLURRY ACTIVITY TO GRADUALLY TAPER OFF FROM
THE WEST. IN THE LOW LEVEL CAA PATTERN...TEMPERATURES HAVE BEEN
STEADILY FALLING THIS MORNING WITH READINGS NOW AT OR A BIT BELOW
FREEZING ACROSS OUR NORTHWEST. AS A RESULT...THERE COULD BE SOME
AREAS OF FREEZING DRIZZLE THIS MORNING BEFORE THE PCPN TAPERS
OFF...ESPECIALLY ACROSS OUR NORTHERN AREAS. WITH THE WARM
TEMPERATURES OF THE PAST FEW DAYS...ROAD SURFACES ARE STILL
RUNNING SEVERAL DEGREES ABOVE FREEZING. THAT BEING SAID..ELEVATED
SURFACES AND UNTREATED BRIDGES/OVERPASSES COULD SEE A LIGHT ICE
ACCUMULATION AND WILL GO AHEAD AND COVER THE THREAT WITH AN SPS.
OTHERWISE...EXPECT CLOUDY SKIES TO CONTINUE THROUGH THE REST OF
THE AFTERNOON IN CONTINUED CYCLONIC LOW LEVEL FLOW. THE
COMBINATION OF CLOUDS AND CAA WILL RESULT IN FAIRLY STEADY TEMPS
TODAY IN THE LOW TO MID 30S.
&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
BASED ON THE UPSTREAM CLOUD COVER AND CONTINUED CYCLONIC
FLOW...SEE NO REASON TO STRAY FROM THE MUCH MORE CLOUDY NAM
SOLUTION THAT KEEPS ABUNDANT LOW LEVEL MOISTURE IN PLACE TONIGHT
INTO THURSDAY. THE LOW LEVELS WILL BEGIN TO DRY OUT THURSDAY AFTERNOON
INTO THURSDAY NIGHT AS A WEAKENING MID LEVEL SHORTWAVE MOVES OUT
OF THE MID MISSISSIPPI VALLEY. FORCING IS PRETTY WEAK BY THE TIME
IT MAKES IT INTO OUR AREA AND WITH ONLY SOME LIMITED
MOISTURE...THINK WE MAY JUST SEE A FEW FLURRIES WITH THIS.
BOUNDARY LAYER TEMPERATURES APPEAR WARM ENOUGH ACROSS THE FAR
SOUTH THURSDAY AFTERNOON TO ALLOW FOR A FEW SPRINKLES TO MIX IN
WITH ANY FLURRY ACTIVITY. EXPECT HIGHS ON THURSDAY RANGING FROM THE
LOWER 30S NORTH TO MID 30S SOUTH...INCREASING INTO THE MID TO
UPPER 30S BY FRIDAY.
&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
HIGH PRESSURE AND DRY CONDITIONS WILL START OUT THE LONG TERM
PERIOD.  THE NEXT SYSTEM WILL BEGIN TO APPROACH THE AREA LATE FRIDAY
NIGHT AND INTO THE DAY ON SATURDAY BEFORE TAPERING OFF SATURDAY
NIGHT.  PRECIPITATION WILL GENERALLY BE IN THE FORM OF LIGHT SNOW
ACROSS THE NW HALF OF THE FA.  PRECIPITATION IS EXPECTED TO START
OFF AS SNOW ACROSS THE SE HALF OF THE FA HOWEVER SOME RAIN IS
EXPECTED TO MIX IN DURING THE DAY BEFORE TRANSITIONING BACK TO LIGHT
SNOW.

HIGH PRESSURE WILL THEN WORK BACK INTO THE AREA FOR SUNDAY AND
MONDAY.  THE NEXT SYSTEM WILL BEGIN TO WORK INTO THE AREA FOR
TUESDAY.  MODELS WERE IN SOMEWHAT DECENT AGREEMENT WITH THIS FEATURE
HOWEVER THE 12Z ECMWF SOLUTION IS NOW SLOWER AND MORE ROBUST.  DID
NOT WANT TO JUMP ON THIS NEW SOLUTION QUITE YET AND WENT WITH MORE
OF A MODEL BLEND FOR TUESDAY.  A MIX OF RAIN AND SNOW ARE EXPECTED
HOWEVER AS COLDER AIR BEGINS TO MOVE INTO THE AREA PRECIPITATION
LOOKS TO CHANGE OVER TO ALL SNOW SHOWERS DURING THE TUESDAY NIGHT
INTO WEDNESDAY TIME PERIOD.

&&

.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
MVFR LOW CLOUDS WILL PREVAIL THROUGH THE TAF PERIOD. THERE
CONTINUE TO BE SIGNIFICANT DISCREPANCIES IN GUIDANCE CONCERNING
CLOUDS POTENTIALLY CLEARING AFTER 15Z. BUT BASED ON WHAT HAS BEEN
OCCURRING UPSTREAM HAVE OPTED TO KEEP FORECAST PESSIMISTIC AND GO
WITH THE NAM AND RAP SOLUTIONS. THERE CONTINUE TO BE SOME
POTENTIAL FOR A BRIEF PERIOD OF IFR CEILINGS EARLY IN THE TAF
PERIOD WHICH HAVE BEEN HANDLED WITH TEMPO. ALSO THE CYCLONIC FLOW
ASSOCIATED WITH THE LOW OVER SE CANADA AND MOVING ENE CONTINUES TO
PRODUCE ENOUGH LOW LEVEL CONVERGENCE OVER THE FORECAST THAT VCSH
HAVE BEEN INTRODUCED TO ALL TAFS TILL AROUND SUNRISE. THE VCSH
WILL BE IN THE FORM OF SNOW SHOWERS AND MAY BRIEFLY LOWER VSBYS
INTO THE MVFR RANGE. NO GOOD WAY TO HANDLE THESE VSBYS IN THE FCST
DUE TO THE TEMPO IFR CLOUDS SO HAVE OPTED TO LEAVE THEM OUT.

SINCE THE INFLUENCE OF THE LOW WILL BE SLOW TO MOVE AWAY FROM THE
FORECAST AREA HAVE INTRODUCE WIND GUSTS BACK INTO THE TAFS ALTHOUGH
AT LOWER SPEEDS THAN YESTERDAY. WEST WINDS AT 15 WITH GUSTS TO 25
KT WILL DECREASE TO 10 TO 15 WITH GUST 20 KT DURING THE DAY AND W
AT 10 KT TONIGHT.

OUTLOOK...MVFR CEILINGS WEDNESDAY NIGHT AND THURSDAY. MVFR
CEILINGS AND VISIBILITIES POSSIBLE FRIDAY NIGHT INTO SATURDAY
NIGHT.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

&&

$$
SYNOPSIS...JGL
NEAR TERM...JGL
SHORT TERM...JGL
LONG TERM...NOVAK
AVIATION...HAYDU








AREA FORECAST DISCUSSION

NWS CHARLESTON WV

 351 AM EST WED DEC 17 2014

.SYNOPSIS...
LOW LEVEL MOISTURE THROUGH THURSDAY NIGHT. HIGH PRESSURE FRIDAY.
LOW PRESSURE SYSTEM FOR THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
LOOKS LIKE WE WILL BE REVERTING TO A SIMILAR SET UP FROM LATE LAST
WEEK WITH TRAPPED MOISTURE IN THE BOUNDARY LAYER UNDER ANOTHER
MASSIVE INVERSION WITH AROUND 60-90MB DEPTH. THIS IS THE BIGGEST
CHANGE TO THE FORECAST WITH GOING 100 SKY COVER ACROSS THE BOARD
THROUGH 12Z THURSDAY. FOLLOWING THE HRRR BRINGS THE CHANCES FOR
MEASURABLE PRECIPITATION TO AN END BY 00Z TONIGHT. CARRY
DRIZZLE/FREEZING DRIZZLE UNTIL 18Z TODAY AND WILL NEED TO MONITOR
THIS TO SEE IF THIS NEEDS TO GO LONGER IN THE FORECAST.

COLD AIR ADVECTION CONTINUING INTO THE OVERNIGHT BRINGS TEMPERATURES
BACK DOWN BELOW FREEZING AREA WIDE. WIND STAYING UP SHOULD KEEP ANY
POTENTIAL FOR FREEZING FOG AT BAY.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY/...
BEFORE THE ADVERTISED STORM SYSTEM FOR THIS WEEKEND...OF WHICH
LITTLE HAS CHANGED IN THAT FORECAST...THE PATTERN ALOFT WILL BE
ZONAL WITH A SERIES OF WEAK UPPER DISTURBANCES MOVING ACROSS THE
AREA. THESE WILL KEEP CONSIDERABLE CLOUDINESS THURSDAY AND
FRIDAY...BUT NO PRECIP ADDED AS MOISTURE IS LIMITED AND THE
DISTURBANCES WILL BE WEAKENING AS THEY MOVE ACROSS. TEMPERATURES WILL
BE NEAR NORMAL FOR THIS TIME OF YEAR.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ACTIVE WEATHER IN THE LONG TERM PERIOD. PERIOD STARTS OUT WITH A
SPLIT UPPER FLOW PATTERN ACROSS THE U.S...WITH A LOW PRESSURE SYSTEM
IN THE SOUTHERN STREAM MOVING EAST ACROSS THE SOUTHEASTERN UNITED
STATES FRIDAY NIGHT INTO SATURDAY...WITH A SHORTWAVE TROUGH IN THE
NORTHERN STREAM PUSHING EAST ACROSS THE OHIO VALLEY...BRINGING A
REINFORCING SHOT OF COLD AIR INTO THE REGION. MODELS ARE STARTING TO
COME INTO BETTER AGREEMENT WITH THE TRACK OF THE LOW...BUT ECMWF IS
DEEPER...AND MORE PROGRESSIVE WITH NORTHERN STREAM SHORTWAVE...THUS
RESULTING IN A COLDER SOLUTION. DEPENDING ON WHICH SOLUN PANS
OUT...COULD SEE MORE OF A WINTRY MIX...AS WITH THE GFS SOLUN...OR A
MAINLY SNOW...WITH POSSIBLY BRIEF RAIN/SNOW MIX ACROSS
LOWLANDS...WITH THE ECMWF SOLUN. HAVE TRENDED THE FORECAST TOWARDS
HPC...WHICH TENDS TO FAVOR WARMER SOLUN. THUS...EXPECTING A WINTRY
MIX TO DEVELOP ACROSS THE AREA FRIDAY NIGHT/SATURDAY...BEFORE
TRANSITIONING TO MAINLY RAIN ACROSS THE LOWLANDS SATURDAY...THEN
BACK TO SNOW OR A MIX SATURDAY NIGHT. ITS POSSIBLE WINTER WEATHER
HEADLINES MAY BE NEEDED DURING THIS PERIOD.

HIGH PRESSURE WILL BUILD IN BEHIND THE SYSTEM FOR EARLY NEXT
WEEK...FOR A BRIEF BREAK IN THE PRECIPITATION...BEFORE ANOTHER
SYSTEM MOVES IN TOWARDS MID WEEK.

&&

.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
LOOKING AT PERSISTENT MVFR CEILINGS/IFR IN BKW THROUGH THE BULK OF
THE PERIOD WITH BRIEF IFR INTO THE DAWN HOURS OVER THE LOWLANDS.
THIS IS THANKS TO ANOTHER DIRTY HIGH PRESSURE SYSTEM WHICH WILL
TRAP MOISTURE IN THE BOUNDARY LAYER LIKE WAS SEEN A FEW DAYS AGO
AND SHOULD YIELD OVERCAST SKIES THROUGH 06Z THURSDAY. USED THE MET
MOS GUIDANCE AND NAM FORECAST SOUNDINGS FOR THIS FORECAST...NOTING
THAT THE LAST 9 HOURS OF THE LAMP GUIDANCE BRINGS CEILINGS UP.
WILL NOT GO WITH THIS FOR THIS ISSUANCE.

NO VISIBILITY RESTRICTIONS EXPECTED WITH 8-12KT WINDS IN PLACE.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z THURSDAY...

FORECAST CONFIDENCE: MEDIUM TO HIGH.

ALTERNATE SCENARIOS: IFR MAY NOT DEVELOP AROUND DAWN. WILL NEED TO
WATCH GUIDANCE FOR CHANGES SUPPORTING VFR AFTER 00Z THURSDAY.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH:   TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW:    TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

DATE                         WED 12/17/14
UTC 1HRLY       08   09   10   11   12   13   14   15   16   17   18   19
EST 1HRLY       03   04   05   06   07   08   09   10   11   12   13   14
CRW CONSISTENCY  H    H    H    H    H    H    M    M    H    H    H    M
HTS CONSISTENCY  H    H    H    H    H    H    H    M    H    H    H    M
BKW CONSISTENCY  L    H    H    M    M    H    H    H    H    H    M    M
EKN CONSISTENCY  L    M    L    L    H    H    H    H    H    H    H    H
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
CKB CONSISTENCY  H    H    H    H    H    H    M    M    H    H    H    H

AFTER 06Z THURSDAY...
IFR POSSIBLE IN WINTRY MIX SATURDAY INTO SUNDAY.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

&&

$$
SYNOPSIS...JMV/26
NEAR TERM...26
SHORT TERM...JMV
LONG TERM...SL
AVIATION...26









AREA FORECAST DISCUSSION

NWS WILMINGTON OH

 112 AM EST WED DEC 17 2014

.SYNOPSIS...
AS LOW PRESSURE MOVES NORTHEAST THROUGH THE GREAT LAKES...A FEW
SHOWERS WILL CONTINUE TO BE POSSIBLE INTO THE OVERNIGHT HOURS.
COOLER CONDITIONS ARE EXPECTED THROUGH THE REST OF THE WEEK...WITH
GENERALLY DRY CONDITIONS. A CHANCE OF RAIN AND SNOW IS IN THE
FORECAST FOR SATURDAY...AS WEAK LOW PRESSURE APPROACHES THE REGION
FROM THE SOUTH.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MID LEVEL TROUGH AXIS IS STARTING TO PUSH EAST OF THE FORECAST
AREA. STILL SOME PATCHY RAIN WORKING ACROSS THE REGION. EXPECT
THIS TO BECOME MORE OF A DRIZZLE WHICH APPEARS TO BE HAPPENING
UPSTREAM. COULD EVEN BE SOME FLURRIES MIXED IN. AT THIS POINT
EXPECT PRECIPITATION TO END BEFORE TEMPERATURES GET BELOW FREEZING
IN THE WESTERN PART OF THE FORECAST AREA. ONLY MADE MINOR
ADJUSTMENTS TO TEMPERATURES BASED ON LATEST DATA. CLOUDS AND GUSTY
WEST WINDS WILL PERSIST THROUGH THE NIGHT.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/...
AS LOW PRESSURE MOVES NORTHEAST OF THE OHIO VALLEY...THE PRESSURE
GRADIENT WILL GRADUALLY RELAX ON WEDNESDAY...BUT CONTINUED COOL
WESTERLY FLOW WILL FORCE TEMPERATURES TO REMAIN BELOW AVERAGE.
ALTHOUGH DRY CONDITIONS ARE EXPECTED...THE BIGGEST FORECAST
CHALLENGE FOR WEDNESDAY WILL BE WITH SKY CONDITIONS. AS HAS BEEN
THE CASE SEVERAL TIMES ALREADY THIS COOL SEASON...THE NAM12
SOLUTION FOR LOW-LEVEL MOISTURE HAS REMAINED MUCH THICKER THAN
OTHER MODELS (GFS/GEM/ECMWF). KEEPING THE BOUNDARY LAYER WELL
MIXED BELOW 3000 FEET THROUGH THURSDAY MORNING...THE NAM12
MAINTAINS A THICK LAYER OF TRAPPED MOISTURE BELOW AN INVERSION.
DESPITE WHAT APPEARS TO BE A CONSENSUS FROM THE OTHER MODELS...THE
NAM12 HAS SHOWN SUCCESS IN THESE SCENARIOS THANKS TO ITS
RESOLUTION IN THE VERTICAL...AND IT CURRENTLY APPEARS TO BE
VERIFYING WELL OVER MISSOURI (WHERE OTHER MODELS ARE ALREADY
SUGGESTING CLEARER CONDITIONS THAN OBSERVED). SKY GRIDS HAVE THUS
BEEN INCREASED ON WEDNESDAY AND INTO WEDNESDAY NIGHT...ALLOWING
FOR SOME BREAKS IN THE EVENING.

AT 500MB ON WEDNESDAY NIGHT...A NARROW RIDGE WILL EXTEND FROM THE
SOUTHERN STATES NORTHWEST INTO THE MIDDLE MISSISSIPPI VALLEY. AS A
WEAK SHORTWAVE MOVES OUT OF THE FOUR CORNERS AREA AND RUNS INTO
THE RIDGE...IT WILL WEAKEN FURTHER...EVENTUALLY WASHING OUT OVER
THE OHIO VALLEY ON THURSDAY. BEFORE THE SYSTEM DISSIPATES...IT
APPEARS THAT SOME WEAK ISENTROPIC LIFT WILL ALLOW FOR AN INCREASE
IN CLOUDS ON THURSDAY...MOVING FROM SOUTHWEST TO NORTHEAST ACROSS
THE OHIO VALLEY. A SLIGHT CHANCE OF PRECIPITATION (MAINLY SNOW)
WAS ALSO INCLUDED...AS MOST LOCATIONS ARE LIKELY TO REMAIN
DRY...BUT SOME LIGHT PRECIPITATION MAY MAKE IT DOWN. MOST OF THE
CLOUDS AND FORCING SHOULD REMAIN ABOVE 5000 FEET...WITH AN
EXTREMELY WEAK SURFACE PRESSURE PATTERN PROVIDING NO SUPPORT.
COLD ADVECTION ON THURSDAY WILL BE MUCH WEAKER WITH THE LIGHTER
FLOW...BUT WITH A RELATIVELY SMALL DIURNAL TEMPERATURE COMPONENT
EXPECTED...TEMPERATURES ON THURSDAY ARE EXPECTED TO REMAIN FAIRLY
SIMILAR TO VALUES ON WEDNESDAY.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE AND DRY CONDITIONS WILL START OUT THE LONG TERM
PERIOD.  THE NEXT SYSTEM WILL BEGIN TO APPROACH THE AREA LATE FRIDAY
NIGHT AND INTO THE DAY ON SATURDAY BEFORE TAPERING OFF SATURDAY
NIGHT.  PRECIPITATION WILL GENERALLY BE IN THE FORM OF LIGHT SNOW
ACROSS THE NW HALF OF THE FA.  PRECIPITATION IS EXPECTED TO START
OFF AS SNOW ACROSS THE SE HALF OF THE FA HOWEVER SOME RAIN IS
EXPECTED TO MIX IN DURING THE DAY BEFORE TRANSITIONING BACK TO LIGHT
SNOW.

HIGH PRESSURE WILL THEN WORK BACK INTO THE AREA FOR SUNDAY AND
MONDAY.  THE NEXT SYSTEM WILL BEGIN TO WORK INTO THE AREA FOR
TUESDAY.  MODELS WERE IN SOMEWHAT DECENT AGREEMENT WITH THIS FEATURE
HOWEVER THE 12Z ECMWF SOLUTION IS NOW SLOWER AND MORE ROBUST.  DID
NOT WANT TO JUMP ON THIS NEW SOLUTION QUITE YET AND WENT WITH MORE
OF A MODEL BLEND FOR TUESDAY.  A MIX OF RAIN AND SNOW ARE EXPECTED
HOWEVER AS COLDER AIR BEGINS TO MOVE INTO THE AREA PRECIPITATION
LOOKS TO CHANGE OVER TO ALL SNOW SHOWERS DURING THE TUESDAY NIGHT
INTO WEDNESDAY TIME PERIOD.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
MVFR LOW CLOUDS WILL PREVAIL THROUGH THE TAF PERIOD. THERE
CONTINUE TO BE SIGNIFICANT DISCREPANCIES IN GUIDANCE CONCERNING
CLOUDS POTENTIALLY CLEARING AFTER 15Z. BUT BASED ON WHAT HAS BEEN
OCCURRING UPSTREAM HAVE OPTED TO KEEP FORECAST PESSIMISTIC AND GO
WITH THE NAM AND RAP SOLUTIONS. THERE CONTINUE TO BE SOME
POTENTIAL FOR A BRIEF PERIOD OF IFR CEILINGS EARLY IN THE TAF
PERIOD WHICH HAVE BEEN HANDLED WITH TEMPO. ALSO THE CYCLONIC FLOW
ASSOCIATED WITH THE LOW OVER SE CANADA AND MOVING ENE CONTINUES TO
PRODUCE ENOUGH LOW LEVEL CONVERGENCE OVER THE FORECAST THAT VCSH
HAVE BEEN INTRODUCED TO ALL TAFS TILL AROUND SUNRISE. THE VCSH
WILL BE IN THE FORM OF SNOW SHOWERS AND MAY BRIEFLY LOWER VSBYS
INTO THE MVFR RANGE. NO GOOD WAY TO HANDLE THESE VSBYS IN THE FCST
DUE TO THE TEMPO IFR CLOUDS SO HAVE OPTED TO LEAVE THEM OUT.

SINCE THE INFLUENCE OF THE LOW WILL BE SLOW TO MOVE AWAY FROM THE
FORECAST AREA HAVE INTRODUCE WIND GUSTS BACK INTO THE TAFS ALTHOUGH
AT LOWER SPEEDS THAN YESTERDAY. WEST WINDS AT 15 WITH GUSTS TO 25
KT WILL DECREASE TO 10 TO 15 WITH GUST 20 KT DURING THE DAY AND W
AT 10 KT TONIGHT.

OUTLOOK...MVFR CEILINGS WEDNESDAY NIGHT AND THURSDAY. MVFR
CEILINGS AND VISIBILITIES POSSIBLE FRIDAY NIGHT INTO SATURDAY
NIGHT.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

&&

$$
SYNOPSIS...HATZOS
NEAR TERM...
SHORT TERM...HATZOS
LONG TERM...NOVAK
AVIATION...HAYDU







AREA FORECAST DISCUSSION

NWS NORMAN OK

 1118 PM CST TUE DEC 16 2014

.AVIATION...
6Z TAFS... MVFR/VFR CONDITIONS FOR THE TAF PERIOD. HOWEVER...
MODEL GUIDANCE IS SUGGESTING IFR OR LOWER CEILINGS COULD BE
POSSIBLE LATE WED AFTN INTO EVENING. RAIN AND DRIZZLE WILL BE
POSSIBLE DURING THE DAY ON WED INTO WED EVENING. ISOLATED THUNDER
MAY ALSO OCCUR NEAR KOKC/KOUN/KLAW/KSPS SITES BUT CHANCES TOO LOW
FOR MENTION IN TAF ATTM. LIGHT FROZEN PRECIP IS ALSO NOT
COMPLETELY OUT OF THE QUESTION IN PARTS OF N OK. CHANCES SEEM LOW
SO WILL LEAVE OUT OF TAFS FOR NOW.

&&

.PREV DISCUSSION... /ISSUED 859 PM CST TUE DEC 16 2014/

UPDATE...
INCREASED SKY COVER TONIGHT. ADDED SPRINKLE MENTION IN SOUTHWESTERN
OKLAHOMA AND WESTERN NORTH TEXAS 4 TO 6 AM WEDNESDAY. INCREASED
RAIN CHANCES NEAR THE RED RIVER EAST OF WICHITA FALLS WEDNESDAY
MORNING.

DISCUSSION...
MOISTURE CONTINUES TO INCREASE ACROSS THE AREA.

BASED ON LATEST SATELLITE AND MODEL DATA...INCREASED CLOUD COVER
TONIGHT. AS A RESULT...THINK TEMPERATURES WILL REMAIN RATHER
STEADY FOR THE REST OF TONIGHT.

ADDED SPRINKLE MENTION TO THE LOCATIONS MENTIONED IN THE
UPDATE LINE AS LATEST MODEL SOUNDINGS AND HRRR SUGGESTED THIS
DEVELOPMENT. ATMOSPHERIC SOUNDINGS AND GROUND TEMPERATURES ABOVE
FREEZING SUPPORT ALL LIQUID IN THESE LOCATIONS.

PARTS OF NORTHERN OKLAHOMA MAINLY NORTHEAST OF A ENID TO
GUTHRIE TO CHANDLER WILL BE NEAR OF JUST BELOW FREEZING...
29 TO 33 DEGREES...THROUGH WEDNESDAY MORNING. IF PRECIPITATION
WERE TO GET THIS FAR NORTH...A LIGHT WINTRY MIX OF MAINLY LIGHT
FREEZING RAIN AND/OR LIGHT SLEET COULD OCCUR. CONFIDENCE IN THIS
SCENARIO REMAINS LOW...ESPECIALLY MOST MODEL RUNS INCLUDING THE
00Z NAM DEPICTING THE HEAVIEST PRECIPITATION WELL SOUTH OF THESE
LOCATIONS. THUS...DID NOT MENTION AT THIS TIME. EVEN IF THIS
WINTRY MIX OCCURRED...TRAVEL IMPACTS WOULD BE VERY UNLIKELY DUE TO
WARMER ROAD SURFACE TEMPERATURES FROM RECENT WARM TEMPERATURES.

PRODUCTS HAVE BEEN UPDATED.

MBS

PREV DISCUSSION... /ISSUED 509 PM CST TUE DEC 16 2014/

AVIATION...
0Z TAFS... VFR/MVFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD.
RAIN CHANCES WILL BEGIN WED MORNING AND CONTINUE THROUGHOUT THE
DAY. ISOLATED THUNDERSTORMS WILL ALSO BE POSSIBLE WED AFTN WITH
MOST LIKELY LOCATIONS BEING KOKC/KOUN/KLAW/KSPS AND POINTS
SOUTHEAST. HOWEVER... THUNDERSTORMS EXPECTED TO BE ISOLATED
ENOUGH THAT WILL LEAVE A MENTION OUT OF TAFS FOR NOW.

PREV DISCUSSION... /ISSUED 238 PM CST TUE DEC 16 2014/

DISCUSSION...
MID-LEVEL MOISTURE FROM THE GULF WILL BEGIN POURING INTO THE
REGION TONIGHT. WITH SOME ISENTROPIC LIFT AND AN APPROACHING
SHORTWAVE...RAIN CHANCES WILL INCREASE THROUGH THE DAY TOMORROW.
SLIGHT RAIN CHANCES WILL CONTINUE INTO THURSDAY BEFORE ANOTHER
SYSTEM MAKES ITS WAY INTO THE AREA. KEPT A MENTION OF SNOW ACROSS
NORTHERN COUNTIES OVERNIGHT WEDNESDAY NIGHT...BUT CONFIDENCE IN
ANY FROZEN PRECIP IS LOW. RAIN AND DRIZZLE ARE MORE LIKELY.

THE MAIN TROUGH APPROACHES FRIDAY...BRINGING RAIN CHANCES TO
SOUTHERN PARTS OF THE CWA. MODELS CONTINUE TO SHOW A DRIER
THURSDAY AND FRIDAY...KEEPING THE MOISTURE FARTHER SOUTH. BROUGHT
POPS DOWN ACCORDINGLY.

BY THE WEEKEND...ANY PRECIP SHOULD BE OUT OF THE AREA. MODELS ARE
STARTING TO COME INTO BETTER ALIGNMENT...SHOWING ANOTHER TROUGH
COMING THROUGH MONDAY OF NEXT WEEK. THOUGH...AS OF YET...THIS
SYSTEM LOOKS TO BE DRY.

TEMPERATURES SHOULD BE SEASONABLY COOL THROUGHOUT THE FORECAST
PERIOD...WITH A GRADUAL WARM UP IN THE BEGINNING OF NEXT WEEK.

MAD

&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  33  42  37  48 /  10  50  50  30
HOBART OK         34  42  36  48 /  10  50  30  20
WICHITA FALLS TX  38  44  40  55 /  10  60  30  10
GAGE OK           32  43  33  43 /  10  30  30  20
PONCA CITY OK     27  40  33  42 /  10  40  60  30
DURANT OK         33  44  39  52 /   0  70  70  20

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

$$

17/25/25



AREA FORECAST DISCUSSION

NWS MEDFORD OR

 206 PM PST WED DEC 17 2014

.DISCUSSION...ANOTHER WEAK UPPER TROUGH IS NEAR THE COAST AND THIS
WILL MOVE INLAND THIS EVENING. CURRENT RADAR SHOWS TWO AREAS OF
SCATTERED SHOWERS. THE FIRST IS IN NORTHEAST SISKIYOU AND KLAMATH
COUNTY AND THE SECOND IS MOVING TOWARDS THE COAST. THIS SECOND
FEATURE WILL MOVE INLAND THIS EVENING AND BRING SCATTERED SHOWERS
OVER NORTHERN CAL AND SOUTHWEST OREGON. THE LATEST RAP MODELS
DEPICTS THE PLACEMENT OF THE PRECIPITATION WELL AND WILL FOLLOW THIS
FOR THIS EVENING. THE UPPER TROUGH WILL WEAKEN AS IT MOVES EAST AND
SHORTWAVE RIDGING BEGINS TO BUILD IN OVERNIGHT. THIS SHOULD SHUT OFF
THE SHOWER ACTIVITY OVER MOST OF THE AREA, ALTHOUGH SOME RESIDUAL
SHOWERS COULD LINGER IN SOUTHEAST SISKIYOU AND MODOC COUNTIES.

WE`LL CATCH A DRY BREAK ON THURSDAY WITH THE RIDGE AXIS OVER THE
AREA, BUT THIS WILL BE SHORT LIVED. THE MODELS SHOW A STRONGER FRONT
APPROACHING THE AREA THURSDAY AFTERNOON BRINGING INCREASING SOUTH
WINDS OVER THE MARINE WATERS WHICH ARE EXPECTED TO GET CLOSE TO
GALES. PRECIPITATION COULD ALSO REACH THE COAST AS EARLY AS THURSDAY
AFTERNOON. THE FRONT WILL MOVE INLAND THURSDAY NIGHT BRINGING
MODERATE TO HEAVY PRECIPITATION OVER THE USUAL SUSPECTS...THE COAST
RANGE...COASTAL MOUNTAINS AND CASCADES. HOWEVER THE MODELS ARE IN
GOOD AGREEMENT THE FRONT WILL BE A QUICK MOVER AND SO WE WON`T GET
SIGNIFICANT PRECIPITATION AMOUNTS. SNOW LEVELS WILL START OUT HIGH
THURSDAY NIGHT, BUT WILL DROP TO AROUND 4500 FEET EARLY FRIDAY
MORNING. SO IT`S A GOOD BET THE MOUNTAIN PASSES WILL GET
ACCUMULATING SNOW STARTING LATE THURSDAY NIGHT THROUGH FRIDAY
MORNING. CURRENT THINKING IS CRATER LAKE COULD PICK UP AT LEAST 6
INCHES OR MORE AND A FEW INCHES ARE POSSIBLE OVER SISKIYOU SUMMIT
AND HIGHWAY 140. KEEP IN MIND THE DETAILS ON THIS WILL CHANGE, SO
STAY TUNED FOR THE LATEST UPDATES.

THE ABOVE MENTIONED FRONT WILL QUICKLY MOVE THROUGH FRIDAY AND WE`LL
CATCH A RELATIVE BREAK IN PRECIPITATION FRIDAY AFTERNOON AND EVENING.
BUT AGAIN THIS WILL BE SHORT LIVED. THE MODELS ARE IN PRETTY GOOD
AGREEMENT SHOWING A STRONG WARM FRONT ARRIVING AT THE COAST LATE
FRIDAY NIGHT AND MOVING OVER THE AREA SATURDAY. THIS FRONT HAS A LOT
OF JUICE WITH IT AND HEAVY PRECIPITATION WILL LIKELY IMPACT THE
COAST...COAST RANGE...COASTAL MOUNTAINS AND CASCADES. MODERATE TO
HEAVY PRECIPITATION WILL ALSO IMPACT MUCH OF THE WESTSIDE VALLEYS. OF
NOTE THE IVT TRANSPORT (WHICH IS GFS BASED) PUTS THE HIGHEST VALUES
IN CENTRAL AND NORTHWEST OREGON. EVEN THE GEFS ENSEMBLE MEAN IS
SIMILAR TO THE OPERATIONAL GFS. ADDITIONALY, THE UPPER FLOW IS
ALMOST DUE WEST WHICH WILL SQUEEZE OUT EVEN MORE MOISTURE ALONG THE
COAST RANGE. ALSO WINDS WILL INCREASE AHEAD OF THE FRONT AND THERE
IS A CHANCE FOR GALE FORCE WINDS OVER THE MARINE WATERS AND MODERATE
TO STRONG WINDS OVER THE COAST AND HEADLANDS. IF THAT WEREN`T ENOUGH
THERE IS CONCERN FOR SNOW EAST OF THE CASCADES AS THE WARM FRONT
ARRIVES. MODEL SOUNDINGS SUPPORT THE IDEA THAT ENOUGH COLD AIR WILL
BE PRESENT NEAR THE SURFACE AND THIS IN COMBINATION WITH OVERRUNNING
PRECIPITATION COULD BRING A PERIOD OF SNOW SATURDAY MORNING.

STRONG WESTERLY FLOW CONTINUES SATURDAY NIGHT WITH THE HEAVIEST
PRECIPITATION WEST OF THE CASCADES, BUT SNOW LEVELS WILL JUMP UP TO
AROUND 7000 FEET SATURDAY AFTERNOON AND REMAIN HIGH SATURDAY NIGHT.
-PETRUCELLI

LONG-TERM FORECAST...SUNDAY THROUGH WEDNESDAY.  A BROAD LONG WAVE
RIDGE WILL BE IN PLACE AT THE BEGINNING OF THE EXTENDED PERIOD WITH
WITH GENERALLY NORTHWEST FLOW ALOFT. SHORT WAVES RIDING OVER THE TOP
OF THE RIDGE WILL WEAKEN IT FROM SUNDAY NIGHT ON...BUT IT WILL
REMAIN IN PLACE THROUGH TUESDAY. THE FLOW ALOFT WILL BECOME MORE
ZONAL TUESDAY.

THIS PATTERN WILL FORCE THE MAIN STORM TRACK TO THE NORTH OF THE
MEDFORD CWA...BUT THE AREA WILL STILL CATCH THE SOUTHERN END OF
SEVERAL SYSTEMS WHICH WILL MOVE ONSHORE DURING THIS INTERVAL. THE
STRONGEST OF THESE SYSTEMS WILL MOVE ONSHORE SATURDAY AFTERNOON AND
EVENING...AND WILL BE OVER THE CWA SUNDAY. REINFORCING SHORT WAVES
WILL KEEP THE PRECIPITATION GOING THROUGH MOST OF MONDAY. THE BULK
OF THE ASSOCIATED PRECIPITATION WILL FALL ALONG THE COAST...COAST
RANGE...AND UMPQUA BASIN. AMOUNTS WILL BE SIGNIFICANT BUT NOT
EXCESSIVE...NO FLOODING PROBLEMS ARE ANTICIPATED. SNOW LEVELS WILL
BE ABOVE 7000 FEET.

MONDAY NIGHT INTO TUESDAY LOOK TO BE MOSTLY DRY WITH NEARLY ALL THE
ACTION TO THE NORTH OF THE AREA.

THE RIDGE WILL BREAK DOWN WEDNESDAY AND A LONG WAVE TROUGH WILL
BEGIN TO DIG OFFSHORE.  THIS CHANGE IN PATTERN WILL SUPPORT A FRONT
MOVING ONSHORE WEDNESDAY. THIS WILL BE THE WETTEST SYSTEM OF THE
EXTENDED PERIOD IF THE CURRENT EC/GFS MODEL SOLUTIONS PAN OUT. SNOW
LEVELS MAY ALSO FALL AS LOW AS 4000 FEET BEHIND THE FRONT WEDNESDAY
NIGHT...SO SNOW MAY RETURN TO THE PASSES AROUND THAT TIME. -JRS


&&

.AVIATION...BASED ON THE 17/18Z TAF CYCLE...VFR CONDITIONS WILL
PREVAIL INITIALLY WITH AREAS OF HIGHER TERRAIN OBSCURED...EXCEPT FOR
WESTERN AND SOUTH CENTRAL SISKIYOU COUNTY...WHERE AREAS OF MVFR CIGS
WILL PREVAIL THROUGH THURSDAY MORNING.  WIDESPREAD MVFR CIGS AND
AREAS OF IFR CIGS/VSBYS WILL RETURN TO THE WEST SIDE TONIGHT. KOTH
WILL BE AFFECTED BY THE MVFR CIGS AND KRBG AND KMFR WILL BE
AFFECTED BY THE IFR CIGS/VSBYS. ALL AREAS WILL CLEAR TO VFR BY
THURSDAY AFTERNOON. -JRS


&&

.MARINE...UPDATED 935 AM PST WED DEC 17 2014...WEAK LOW PRESSURE
SYSTEMS WILL MOVE THROUGH THE AREA TODAY AND TONIGHT. SOUTHWEST
SWELL DOMINATED SEAS WILL REMAIN MOSTLY AT OR ABOVE 10 FEET TODAY.
THURSDAY INTO THURSDAY NIGHT A STRONGER FRONTAL SYSTEM WILL LIKELY
BRING GALE FORCE WINDS AND VERY STEEP SOUTHWEST SEAS. HEAVY WEST
SWELL WILL BEGIN TO ARRIVE IN THE PREDAWN HOURS FRIDAY MORNING. IT
WILL PEAK FRIDAY NIGHT AT AROUND 19 FEET AT 18 SECONDS. A WARM FRONT
WILL MOVE THROUGH FRIDAY NIGHT...FOLLOWED BY A COLD FRONT SATURDAY.
OFFSHORE HIGH PRESSURE WILL BUILD SATURDAY NIGHT INTO SUNDAY. -JRS


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...NONE.

PACIFIC COASTAL WATERS...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     PZZ350-356-370-376.
     HAZARDOUS SEAS WATCH FROM THURSDAY AFTERNOON THROUGH LATE
     THURSDAY NIGHT FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST THIS
     AFTERNOON FOR PZZ350-356-370-376.

$$



AREA FORECAST DISCUSSION

NWS MEDFORD OR

 930 PM PST TUE DEC 16 2014

.DISCUSSION...LOW PRESSURE OVER THE COASTAL WATERS WILL MOVE EAST
TO NORTHEAST TONIGHT WITH COLD FRONTAL PRECIPITATION FOCUSED FROM
THE MT SHASTA AREA SOUTHWARD. IT IS PRESENTLY 38 DEGREES AND
RAINING AT MT SHASTA CITY. PRECIPITATION ALONG THE I-5 CORRIDOR
IN FAR SOUTH CENTRAL SISKIYOU COUNTY WILL LIKELY CHANGE OVER TO
SNOW LATE TONIGHT...SHORTLY AFTER 2 AM...WITH THE SNOW LEVEL
IN THAT LOCAL AREA DROPPING TO AROUND 3000 FEET WITH MORE INTENSE
PRECIPITATION RATES LOWERING THE SNOW LEVEL. SNOWFALL AMOUNTS
TONIGHT ARE FORECAST TO BE AROUND 1 TO 3 INCHES NEAR MT SHASTA.
MEANTIME, THERE IS A CHANCE OF LIGHT SNOW OVER THE SOUTHERN
OREGON CASCADES AND EAST SIDE WITH NOT MUCH MORE THAN A DUSTING AT
ELEVATIONS ABOVE 4500 FEET.

A MORE WIDESPREAD SHOWERY PATTERN WILL DEVELOP FOR OUR AREA ON
WEDNESDAY...ESPECIALLY ON THE WEST SIDE. THE SNOW LEVEL WILL
REMAIN AROUND 4500 FEET WITH 1 TO 3 INCHES OF SNOW POSSIBLE FOR
THE SOUTHERN OREGON SISKIYOU AND CASCADE MOUNTAINS. SHOWERS AND
SNOW SHOWERS WILL DIMINISH WEDNESDAY NIGHT AS A RIDGE BUILDS TO
THE COAST.

A FOCUS FOR THE NIGHT SHIFT WILL BE ON THE DETAILS OF WHAT LOOK TO
BE STRONGER FRONTS TO AFFECT OUR AREA THURSDAY EVENING INTO
FRIDAY AFTERNOON AND THEN SATURDAY INTO EARLY SUNDAY. THIS SECOND
SYSTEM ON THE WEEKEND HAS HIGHER UNCERTAINTY/MODEL SOLUTION
VARIABILITY.

&&

.AVIATION...BASED ON THE 17/00Z TAF CYCLE...CONDITIONS REMAIN VFR
ACROSS THE MEDFORD CWA THIS EVENING WITH THE NOTABLE EXCEPTION OF
MVFR CEILINGS OVER SOUTHERN SISKIYOU COUNTY WITH MOUNTAIN
OBSCURATION AND LIGHT TO MODERATE RAIN AND SNOW. ALSO...STRONG
SOUTHERLY LOW LEVEL WINDS WILL DIMINISH AFTER MIDNIGHT.
OVERNIGHT...AREAS OF MVFR CIGS IN PRECIPITATION WILL INCREASE
ALONG THE SOUTH COAST RANGE AND OVER MOST OF SISKIYOU COUNTY WITH
HIGHER TERRAIN OBSCURED. ISOLATED IFR CIGS/VSBYS IN LOW CLOUDS AND
FOG ARE POSSIBLE OVER THE WESTERN VALLEYS LATE TONIGHT THROUGH
MID-MORNING WEDNESDAY...MAINLY IN THE UMPQUA BASIN.

&&

.MARINE...UPDATED 800 PM PST TUE DEC 16 2014...LOW PRESSURE
OVER THE WATERS WILL MOVE NORTHEAST TONIGHT WITH INCREASING SOUTH
WINDS AND BUILDING SEAS...ESPECIALLY SOUTH OF CAPE BLANCO AND
BEYOND 10NM OFFSHORE. WINDS WILL VEER TO WESTERLY EARLY WEDNESDAY
THEN RETURN TO SOUTHERLY BY WEDNESDAY NIGHT. A STRONGER FRONT WILL
PUSH THROUGH ON THURSDAY WITH STRONG SOUTH WINDS POSSIBLY REACHING
GALE STRENGTH. VERY HEAVY WEST SWELL AROUND 20 FEET WITH A
DOMINANT PERIOD OF 19 SECONDS WILL ARRIVE ON FRIDAY AND LIKELY
REMAIN VERY HIGH INTO SATURDAY.

&&

.PREV DISCUSSION... /ISSUED 216 PM PST TUE DEC 16 2014/

DISCUSSION...PRECIPITATION AHEAD OF A SURFACE LOW NEAR 42N/128W IS ALREADY
REACHING CAPETOWN CALIFORNIA AND IS MOVING NORTH TO NORTHEAST. THE
RAP IS DOING FAIRLY WELL IN INITIALIZING THE POSITION OF THE LOW AND
QPF FIELDS THIS AFTERNOON AND HAVE LEANED TOWARDS THIS SOLUTION FOR
THIS EVENING. WINDS HAVE INCREASED AHEAD OF THE LOW IN THE SHASTA
VALLEY AND WILL LAST THROUGH THE NIGHT, BUT DO NOT EXPECT THEM TO
REACH ADVISORY CRITERIA. THE RAP SHOWS THE PRECIP FIELD BREAKING UP
INTO TWO PARTS THIS EVENING. ONE PART WILL MOVE NORTH OVER THE
MARINE WATERS, THE OTHER WILL CONTINUE TO PUSH EAST INTO NORTHERN
CAL AND INTO THE MOUNT SHASTA REGION. THE PARAMETERS ON THE NAM WITH
RESPECT TO SNOW NEAR AND AT MOUNT SHASTA HAVE CHANGED LITTLE FROM
THE PREVIOUS RUN. IT STILL LOOKS FAVORABLE FOR HEAVIER PRECIPITATION
TO DEVELOP LATER THIS EVENING AND TONIGHT DUE TO UPSLOPE FLOW AND
850 MB TEMPERATURES NEAR 0C. IN ADDITION 700MB FLOW IS FROM THE
SOUTH BETWEEN 40-50 KTS. THE MAIN QUESTION WILL BE HOW MUCH. CURRENT
THINKING IS THAT WE`LL HAVE A RAIN WET SNOW MIX TO START THIS
EVENING WITH MODEL SOUNDINGS RIGHT AT THE CUSP BETWEEN RAIN AND
SNOW. PRECIPITATION WILL INCREASE TONIGHT FORCING THE SNOW LEVEL
DOWN LOW ENOUGH TO GET INTO MOUNT SHASTA. SNOW RATIONS WILL BE LOW,
BUT QPF VALUES SUGGEST WE COULD PICK UP AT LEAST 3 INCHES OR MORE
NEAR THE INTERSTATE, ESPECIALLY BETWEEN MOUNT SHASTA AND DUNSMUIR.
IT`S POSSIBLE HIGHWAY 89 COULD GET UP TO 6 INCHES OR MORE BY
DAYBREAK WEDNESDAY.

THE UPPER TROUGH MOVES THROUGH WEDNESDAY MORNING AND THE UPPER FLOW
WILL BECOME WESTERLY WHICH WILL LIMIT THE AMOUNT OF PRECIPITATION
IN THE MOUNT SHASTA REGION. ELSEWHERE VALLEY RAIN AND MOUNTAIN
SNOW SHOWERS WILL LINGER, BUT WERE NOT EXPECTING ANYTHING
NOTEWORTHY WITH MINIMAL IMPACT ON PASSES. SOME LEFTOVER SHOWERS
WILL LINGER INTO WEDNESDAY EVENING, THEN END OVERNIGHT AS
SHORTWAVE RIDGING BUILDS INTO THE AREA. WE`LL CATCH A DRY BREAK ON
THURSDAY WITH THE RIDGE AXIS OVER THE AREA, BUT THIS WILL BE SHORT
LIVED. THE MODELS SHOW A STRONGER FRONT APPROACHING THE AREA
THURSDAY AFTERNOON BRINGING INCREASING SOUTH WINDS OVER THE MARINE
WATERS WHICH COULD GET CLOSE TO GALES.

THIS FRONT WILL PUSH INLAND THURSDAY NIGHT WITH PRECIPITATION
SPREADING OVER MUCH OF THE FORECAST AREA. THE HEAVIEST AMOUNTS WILL
BE ALONG THE COAST RANGE, COASTAL MOUNTAINS AND CASCADES. RIGHT NOW
SNOW LEVELS WILL START OUT HIGH THURSDAY EVENING, BUT WILL DROP
TO AROUND 4500 FEET EARLY FRIDAY MORNING. SO IT`S A GOOD BET THE
MOUNTAIN PASSES WILL GET ACCUMULATING SNOW STARTING LATE THURSDAY
NIGHT THROUGH FRIDAY MORNING. RIGHT NOW, IT LOOKS LIKE CRATER LAKE
COULD PICK UP AT LEAST 6 INCHES OR MORE...A FEW INCHES OVER
SISKIYOU SUMMIT AND HIGHWAY 140. KEEP IN MIND THE DETAILS ON THIS
WILL CHANGE, SO STAY TUNED FOR THE LATEST UPDATES, ESPECIALLY FOR
ANYONE PLANING ON TRAVELING THE WEEKEND BEFORE CHRISTMAS.
-PETRUCELLI

LONG-TERM FORECAST...SATURDAY THROUGH TUESDAY.  A BROAD LONG WAVE
RIDGE WILL BUILD INTO THE WEST COAST SATURDAY AND SUNDAY...WITH
GENERALLY NORTHWEST FLOW ALOFT. SHORT WAVES RIDING OVER THE TOP OF
THE RIDGE WILL WEAKEN IT FROM SUNDAY NIGHT ON...BUT IT WILL REMAIN
IN PLACE THROUGH TUESDAY. THE FLOW ALOFT WILL BECOME MORE ZONAL
THOUGH.

THIS PATTERN WILL FORCE THE MAIN STORM TRACK TO THE NORTH OF THE
MEDFORD CWA...BUT THE AREA WILL STILL CATCH THE SOUTHERN END OF
SEVERAL SYSTEMS WHICH WILL MOVE ONSHORE DURING THIS INTERVAL.  THE
STRONGEST OF THESE SYSTEMS WILL MOVE ONSHORE SATURDAY AFTERNOON AND
EVENING...AND AGAIN MONDAY. THE BULK OF THE ASSOCIATED PRECIPITATION
WILL FALL ALONG THE COAST...COAST RANGE...AND UMPQUA BASIN. AMOUNTS
WILL BE SIGNIFICANT BUT NOT EXCESSIVE...NO FLOODING PROBLEMS ARE
ANTICIPATED. SNOW LEVELS WILL START OFF BETWEEN 4000 AND 5000 FEET
SATURDAY...BUT WILL RISE TO ABOVE 7000 FEET SATURDAY NIGHT INTO
SUNDAY AND REMAIN ABOVE ALL BUT THE HIGHEST TERRAIN UNTIL IT LOWERS
SLIGHTLY TUESDAY NIGHT. SO...THE HEAVIEST SNOWS WILL OCCUR WITH THE
SATURDAY SYSTEM.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST WEDNESDAY FOR
     CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST
     WEDNESDAY FOR PZZ356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST
     WEDNESDAY FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PST WEDNESDAY FOR
     PZZ376.

$$

DW/DW/SBN



AREA FORECAST DISCUSSION

NWS PORTLAND OR

 912 PM PST TUE DEC 16 2014

.SYNOPSIS...A CLOSED LOW JUST OFFSHORE WEST OF THE OR/CA BORDER WILL
SLOWLY WEAKEN AND PUSH NORTHWARD OVERNIGHT...EVENTUALLY MOVING
ONSHORE ALONG THE N OR/S WA COAST TOMORROW AFTERNOON. THIS WILL
MAINTAIN LIGHT SHOWER ACTIVITY...MAINLY OVER THE HIGHER TERRAIN
OVERNIGHT AND TOMORROW MORNING. AN UPPER LEVEL SHORTWAVE WILL PUSH
ONSHORE LATER TOMORROW...LIKELY BRINGING A PERIOD OF STEADIER
RAINFALL THROUGH EARLY THU MORNING. EXPECT A FAIRLY QUIET PERIOD FOR
MUCH OF THE DAY THU...BUT THEN A MORE ORGANIZED FRONT WILL BRING
GUSTY WINDS AND LARGE SURF TO THE COAST...WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL LIMIT SNOW TO THE
HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY RESULT IN SOME
SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING AND SATURDAY.
WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND. THERE IS THE
POTENTIAL FOR AN ATMOSPHERIC RIVER TYPE SET UP AND ASSOCIATED HEAVY
RAIN TO DEVELOP OVER THE WEEKEND INTO EARLY NEXT WEEK.

&&

.EVENING UPDATE...A LOW PRES CIRCULATION IS APPARENT ON SATELLITE AND
RADAR IMAGERY THIS EVENING JUST OFFSHORE OF THE CA/OR BORDER. WATER
VAPOR SATELLITE SHOWS MOISTURE SPREADING NORTHWARD FROM THIS SYSTEM
INTO NW OREGON AND SW WASHINGTON. THERE ARE ALSO LIGHT ECHOES SHOWING
UP ON RADAR OVER THE SOUTHERN AND WESTERN PORTIONS OF OUR FCST
AREA...BUT LITTLE TO NO RAIN IS REACHING THE GROUND AT THIS TIME.
EXPECT AS THE NIGHT GOES ON AND THE OFFSHORE LOW SLOWLY MOVES
NORTHEAST...WE WILL SEE LIGHT PRECIPITATION START TO REACH THE
SURFACE...ESPECIALLY OVER THE HIGHER TERRAIN. A WEAK VORT MAX WILL
ALSO MOVE ONSHORE EARLY WED MORNING...WHICH MAY HELP AID THE SHOWERS.

THE MAIN CHANGE TO THE FCST THIS EVENING WAS TO INCREASE POPS AND QPF
FROM THE 18Z WED TO 12Z THU TIME FRAME. THE CLOSED LOW JUST OFFSHORE
TONIGHT WILL SLOWLY WEAKEN AND PUSH ONSHORE AROUND MIDDAY TOMORROW.
MEANWHILE...THE SHORTWAVE NOW APPARENT ON WATER VAPOR SATELLITE
NEARING 45N 140W IS MODELED TO STRETCH OUT AND PUSH ONSHORE LATER
TOMORROW AFTERNOON AND EVENING. THE LOWER LEVEL MOISTURE ASSOCIATED
WITH THE SURFACE LOW COMBINED WITH THE UPPER LEVEL FORCING FROM THE
SHORTWAVE SHOULD DRIVE A PERIOD OF STEADIER PRECIP LATER TOMORROW
AND TOMORROW NIGHT. THE 00Z NAM AND GFS RUNS PICKED UP ON THIS
PERIOD OF ENHANCED PRECIP. THE VORT MAX PUSHES EAST OF THE CASCADES
BY 12Z THU...AFTER WHICH SHOWER ACTIVITY SHOULD DROP OFF
SIGNIFICANTLY. PYLE

.PREV DISC ISSUED 231 PM PST TUE DEC 17...

.SHORT TERM...TONIGHT THROUGH FRIDAY...SHOWERS HAVE PRETTY MUCH ENDED
OVER THE PORTLAND FORECAST AREA EARLY THIS AFTERNOON...EXCEPT FOR
VERY INFREQUENT ISOLATED SHOWER OVER THE SW WASHINGTON CASCADES.
SATELLITE IMAGERY SHOWS A SURFACE LOW AROUND 150 MILES WEST OF THE
SOUTHERN OREGON COAST...NEAR 42N 127W. THE HIGHER RESOLUTION
MODELS...HRRR AND RAP INITIALIZE BEST WITH THE LOW AND FORECAST RAIN
MOVING NORTH INTO LANE COUNTY SLIGHTLY EARLIER THAN THE OTHER MODELS.
HAVE TRENDED TOWARDS THIS EARLIER ARRIVAL...BUT ONLY HAVE FAIR
CONFIDENCE THAT THE TIMING WILL PAN OUT. ANY RAIN LATE THIS AFTERNOON
SHOULD BE FAIRLY LIGHT AND REMAIN WEST OF THE SOUTH AND CENTRAL
WILLAMETTE VALLEY.

THE LOW WILL MOVE CLOSER TO THE SOUTHERN OREGON COAST LATE THIS
AFTERNOON AND EVENING THEN MOVE ONTO THE CENTRAL OREGON COAST AS AN
UPPER TROUGH LATE TONIGHT...WITH SHOWERS MAINLY OVER THE HIGHER
TERRAIN THROUGH WEDNESDAY MORNING. SOME CLEARING EARLY WED MORNING
MAY RESULT IN SHALLOW FOG AND LOW CLOUDS IN SOME OF THE INTERIOR
VALLEYS...MAINLY SOUTH OF SALEM.

EASTERLY WINDS HAVE HELD ON TODAY WITH A TROUTDALE TO DALLES PRESSURE
GRADIENT HOLDING AROUND 5 MB. THIS GRADIENT SHOULD TIGHTEN A LITTLE
THIS EVENING AS THE LOW MOVES CLOSER TO THE COAST AND MAINTAIN GUSTS
AROUND 30 MPH THROUGH THE WESTERN COLUMBIA RIVER GORGE.

SHOWERS WILL CONTINUE WEDNESDAY...MAINLY FOR THE HIGHER TERRAIN AS
THE PARENT UPPER LEVEL TROUGH MOVES OVER THE PACIFIC NW. SHOWERS
SHOULD END OVERNIGHT AS AN UPPER RIDGE BUILDS OVER THE AREA AND
EXPECT THAT CLEARING SKIES AND LIGHT WINDS WILL LEAD TO SHALLOW FOG
FOR THE INTERIOR VALLEYS EARLY THURSDAY MORNING. MOST OF THURSDAY
WILL BE DRY WITH AN INCREASE OF MID AN HIGH LEVEL CLOUDS IN THE
AFTERNOON.

MODELS ARE IN GOOD AGREEMENT THAT A WELL ORGANIZED FRONT WILL BRING
GUSTY WINDS TO THE COAST THURSDAY EVENING WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. PRECIPITABLE WATER IS EXPECTED TO BE NEAR
AN INCH AND AN APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND
EXPECT THE HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE
COAST AND COAST RANGE THURSDAY NIGHT THROUGH FRIDAY MORNING. OTHER
AREAS SHOULD SEE BETWEEN 0.4 AND 0.60 INCH OF RAIN. SNOW LEVELS
SHOULD REMAIN ABOVE 5000 FEET DURING THE PEAK RAIN PERIOD...BUT LOWER
TO NEAR OR BELOW THE CASCADE PASSES BEHIND THE FRONT FRIDAY
AFTERNOON.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...A BROAD RIDGE OF HIGH
PRESSURE OVER THE WESTERN U.S. FLATTENS AS A STRONG LOW PRESSURE
SYSTEM OVER THE GULF OF ALASKA MOVES INLAND TO OUR NORTH. AS THIS
TROUGH MOVES ON SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES
ONSHORE AND STALLS EAST-TO-WEST ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON. THIS PUTS OUR AREA IN THE PATH OF RAIN
STARTING SATURDAY THROUGH MONDAY. SOME UNCERTAINTY EXISTS IN WHERE
THIS BOUNDARY WILL SET UP...WHICH WILL DETERMINE HOW MUCH RAINFALL
WE WILL GET. ON TUESDAY...GEFS ENSEMBLE SPAGHETTI PLOTS GET MESSY
AND SIGNIFICANT DIFFERENCES START TO SHOW UP BETWEEN THE GFS AND
ECMWF...DECREASING CONFIDENCE ON HOW THE REST OF THE WEEK WILL SHAPE
UP.  AS OF NOW...THE MOST COMMON SOLUTION IS THAT HIGH PRESSURE
RIDGING WILL START TO BUILD BACK OVER THE WESTERN U.S. WHICH
SUGGESTS DRIER WEATHER STARTING TUESDAY...THOUGH UNCERTAINTY IS VERY
HIGH. -MCCOY

&&

.AVIATION...MOIST SOUTHERLY FLOW ALOFT...WITH PLENTY OF MID AND
HIGH CLOUDS OVER REGION. DO HAVE AREAS OF MVFR CIGS ALONG THE
COAST AND WILL SEE THOSE PERSIST OVERNIGHT INTO WED AM. QUESTION
IS WHETHER OR NOT LOW CLOUDS REFORM S OF SALEM TONIGHT. HAVE
CLEARED OUT AT MOMENT...WITH STILL RATHER HIGH HUMIDITY. SO
SUSPECT WITH OCCASIONAL LIGHT RAIN THERE...WILL SEE AREAS OF IFR
STRATUS REFORM TONIGHT TO SOUTH OF KSLE.

KPDX AND APPROACHES...VFR WILL PERSIST TONIGHT AND WED...BUT CIGS
LOWER TO 5K FT LATER AFTER 09Z WITH OCCASIONAL LIGHT RAIN THROUGH
17Z. VFR WITH LOT OF MID AND HIGH CLOUDS ON WED.ROCKEY.
 &&

.MARINE...NOT MUCH CHANGE. GRADIENTS WEAKENING THIS EVENING AS
LOW HEADS INTO N CALIF. STILL...WILL GET A GUSTS TO 25 KT ON THE
OUTER SOUTH WATERS THIS EVENING. SEAS HOLDING AT 8 TO 9 FT.

NEXT SYSTEM NOW DEVELOPING WAY OFFSHORE BETWEEN 160W-170W. THIS
SYSTEM WILL BRING SOUTHERLY GALES TO THE WATERS LATER THU THROUGH
EARLY FRI AM. STILL SOME UNCERTAINTY ON EXACT TIMING AND DETAILS
BUT WILL BE VERY ACTIVE PERIOD. SEAS LIKELY TO PUSH BACK INTO THE
UPPER TEENS TO NEAR 20 FT BY FRI AM.

MORE FRONTS ARRIVE THIS WEEKEND INTO EARLY NEXT WEEK...WITH
SOUTHERLY GALES LIKELY AND ENHANCED SEAS.   ROCKEY.
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FOR THU AND THU NIGHT ON ALL COASTAL WATERS.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR TONIGHT
AND AGAIN 11 AM TO 4 PM WED.

&&


$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
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 GREENVILLE-SPARTANBURG SC

 1253 PM EST WED DEC 17 2014

.SYNOPSIS...
HIGH PRESSURE WILL SPREAD BACK OVER THE REGION TODAY BEHIND A
DEPARTING COLD FRONT. A WEAK WEATHER SYSTEM ALOFT WILL SPREAD CLOUDS
AND PERHAPS SOME SPOTTY LIGHT SHOWERS IN THE MOUNTAINS ON THURSDAY.
ANOTHER LOW WILL DEVELOP TO OUR SOUTHWEST ON FRIDAY AND INCREASE
CHANCES FOR WIDESPREAD PRECIPITATION GOING INTO THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
930 AM EST UPDATE...HAVE DECREASED THE CLOUD COVER OVER PORTIONS OF
THE NC MTNS/VALLEYS PER LATEST VISBY SATELLITE IMAGERY TREND.
OTHERWISE...CURRENT FORECAST REMAINS ON TRACK.

AS OF 600 AM EST WEDNESDAY...LATEST RADAR TRENDS REMAIN RATHER
UNIMPRESSIVE REGARDING POSSIBLE LIGHT SHRA ACROSS THE NORTHERN
MTNS.  THUS POP FCST WILL REMAIN AS IS WHICH FEATURES ALL POPS BEING
REMOVED WITH THE HOUR.  LOW LEVEL STRATUS ACROSS THE MTNS IS STILL
FCST TO SCATTER THROUGH MORNING.  MADE SLIGHT TWEAKS TO TEMPERATURES
AND DEWPOINTS TO REFLECT LATEST OBSERVATIONS.

PREVIOUS DISCUSSION...

AS OF 300 AM EST WEDNESDAY...QUASI ZONAL UPPER FLOW MIGRATING OVER
THE SOUTHEAST WHILE CANADIAN HIGH PRESSURE DIVES SOUTHWARD THROUGH
THE MS RIVER VALLEY INTO THE OH/TN VALLEYS.  MODEST WEST/NORTHWEST
850MB FLOW ALONG THE CENTRAL APPS CONTINUES TO YIELD SCATTERED
SHOWERS ACROSS PORTIONS OF EASTERN KY NORTHWARD INTO WEST VIRGINIA.
ALTHOUGH AMPLE MOISTURE REMAINS FURTHER SOUTH ACROSS PORTIONS OF
WESTERN NC...WEAKER FLOW CONTINUES TO LIMIT COVERAGE.  LATEST
NAM/GFS REMAIN PERSISTENT IN SUGGESTING INCREASING SHOWER COVERAGE
ALONG THE TN LINE NORTH OF INTERSTATE 40 THROUGH MID MORNING.
HOWEVER...HIGH RES GUIDANCE SUCH AS THE HRRR CONTINUES TO BACK OFF.
ALL SAID...WILL KEEP LOW END SLIGHT CHANCE POPS FOR ISOLATED SHOWERS
ACROSS THE NORTHERN MTNS THROUGH 12Z.  FCST DOES FEATURE BRIEF
PERIOD OF FZRA FOR THESE ZONES AS MODEST INVERSION ALOFT SUGGESTS
PRECIP WILL FALL AS LIQUID WITH SOME FREEZING POSSIBLE TOWARD
MORNING LOWS.  NOT EXPECTING ANY SIGNIFICANT IMPACTS BUT CANNOT RULE
OUT A FEW PATCHES OF BLACK ICE.

BEYOND THAT...HIGH PRESSURE WILL PREVAIL ACROSS THE REGION WITH
MOSTLY SUNNY SKIES DOMINATING OVER THE LOW TERRAIN.  DID KEEP
MENTION OF MOSTLY/PARTLY CLOUDY SKIES ACROSS THE HIGH TERRAIN AS
WEAK WESTERLY UPSLOPE FLOW CONTINUES AMONGST SHALLOW MOIST LAYER.
MEANWHILE ANOTHER WEAK UPPER IMPULSE WILL BE SLIDING THROUGH THE
SOUTHERN PLAINS ALLOWING SOME HIGH LEVEL CIRRUS TO MOVE OVER THE
FCST AREA THIS AFTERNOON THROUGH PERIODS END.  DOWNSLOPING FLOW WILL
YIELD NORMAL LEVEL HIGH TEMPERATURES ACROSS THE FOOTHILLS/PIEDMONT
REGIONS WHILE SLIGHTLY BELOW NORMAL HIGHS ARE FCST OVER THE MTNS.
LOWS TONIGHT WILL BE NEAR NORMAL AS ABOVE MENTIONED INCREASING HIGH
LEVEL CIRRUS LIMITS RADIATIONAL COOLING.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 325 AM WEDNESDAY...A WEAK SHORT WAVE WILL MOVE THRU THE ZONAL
FLOW ALOFT THU. THERE IS VERY LITTLE DEEP MOISTURE OR FORCING WITH
THIS SYSTEM. CANNOT RULE OUT A FEW SPRINKLES ACROSS THE NC MTNS
WHERE WLY FLOW MAY BE ABLE TO SQUEEZE THEM OUT OF THE MOISTURE.
THERE SHUD BE QUITE A BIT OF CLOUDS ACROSS THE AREA HOWEVER. SHORT
WAVE RIDGING DEVELOPS AHEAD OF THE NEXT WX SYSTEM APPROACHING FROM
THE SW ON FRI. THIS WILL BRING AN INCREASE IN CLOUDS THRU THE DAY
AFTER THE THU NITE CLEARING FROM THE DEPARTING SHORT WAVE. HIGHS
WILL BE NEAR NORMAL BOTH DAYS...WHILE LOWS THU NITE WILL BE A FEW
DEGREES ABOVE NORMAL.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 355 AM WEDNESDAY...GUIDANCE REMAINS IN GOOD AGREEMENT ON THE
OVERALL PATTERN FOR THE WEEKEND STORM SYSTEM...BUT SOME DIFFERENCES
REMAIN REGARDING THE TEMPERATURE PROFILE AND RESULTING P-TYPES. A
SHORT WAVE APPROACHES THE AREA FRI NITE...MOVES ACROSS THE AREA SAT
AND EAST ON SAT NITE. AT THE SFC...A LOW PRESSURE SYSTEM MOVES EAST
ALONG THE GULF COAST WHILE HIGH PRESSURE SETS UP OVER THE AREA IN A
COLD AIR DAMMING CONFIGURATION. PRECIP CHC INCREASES FROM THE SW FRI
NITE AS MOISTURE MOVES IN AHEAD OF THIS SYSTEM...CAT POP DEVELOPS
ALL AREAS SAT AS THE LOW MOVES SOUTH OF THE AREA...WITH POP SLOWLY
TAPERING OFF SAT NITE AND ENDING ON SUN. THE GFS IS WARMER THAN THE
ECMWF...BUT THE ECMWF IS NOT VERY COLD. USING A BLEND OF THESE TWO
MDLS FOR TEMPS AND THICKNESSES RESULTS IN COLDEST TEMPS AND
THICKNESSES ALONG THE NRN TIER OF THE CWFA...POSSIBLY EXTENDING
SOUTH ALONG THE BLUE RIDGE TO THE SC BORDER. EVEN THEN...P-TYPE
SEEMS TO FAVOR A WINTRY MIX FOR THE NRN BLUE RIDGE AND FREEZING RAIN
EAST AND SOUTH OF THERE. RAIN IS THE P-TYPE FOR MOST OF THE CWFA.
CANNOT RULE OUT ADVISORY LEVEL ICE ACCUMS FOR THE NRN MTN LOCATIONS
LATE FRI NITE AND SAT MORN. HAVE GONE WITH RAIN OR SNOW AS PRECIP
COMES TO AN END SAT NITE AND SUN MORN...BUT THIS AND ANY POTENTIAL
ACCUMS ARE MUCH MORE UNCERTAIN. LOWS WILL BE ABOVE NORMAL FRI AND
SAT NITES...WITH HIGHS SAT 10 DEGREES BELOW NORMAL...RISING TO A FEW
DEGREES BELOW NORMAL ON SUN.

GUIDANCE BEGINS TO DIVERGE FOR THE REST OF THE MEDIUM RANGE. A DEEP
TROF DEVELOPS ACROSS THE CENTRAL CONUS...BUT THE ECMWF IS SLOWER AND
DEEPER WITH THE TROF THAN THE GFS. THE GFS ALSO BRINGS SOME WEAK
SHORT WAVE ENERGY ACROSS THE AREA AHEAD OF THE TROF ON MON...WHILE
THE ECMWF DAMPENS THE WAVE SIGNIFICANTLY. AT THE SFC...THE GFS HAS A
WELL DEFINED LOW PRESSURE SYSTEM WELL SOUTH OF THE AREA ACROSS
FLORIDA AND MOVES IN INTO THE ATLANTIC...KEEPING OUR CWFA RELATIVELY
DRY...WHILE THE ECMWF HAS A LESS DEFINED SFC LOW...BUT A STRONGER
BAROCLINIC ZONE CLOSER TO THE CWFA SPREADING PRECIP IN FROM THE
SOUTH. GIVEN THE DISCREPANCIES...HAVE KEPT MON BASICALLY DRY WITH
TEMPS NEAR NORMAL.

PRECIP SPREADS BACK INTO THE AREA TUE AS A FRONTAL SYSTEM ASSOCIATED
WITH THE UPPER TROF MOVES BACK INTO THE AREA FROM THE WEST.
HOWEVER...DETAILS DIFFER ON EXACT TIMING AND THERMAL STRUCTURE.
THEREFORE...HAVE CHC POP SPREADING IN FROM THE WEST TUE. AGAIN...
GIVEN THE DIFFERENCES...USED RAIN/SNOW FOR THE P-TYPE WHICH WOULD
INDICATE SOME SNOW AT ONSET ACROSS THE NC MTNS...BUT THIS IS ALSO
HIGHLY UNCERTAIN. TEMPS TUE NEAR NORMAL.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AT KCLT AND ELSEWHERE...VFR CONDITIONS WILL PREVAIL THROUGH THE TAF
PERIOD FOR ALL TERMINALS AS HIGH PRESSURE CONTINUES TO BUILD IN FROM
THE WEST. W/WSW WINDS THIS AFTERNOON WILL DECREASE VEER TO THE NW BY
THIS EVENING. WINDS WILL THEN VEER TO THE NE BY LATE TONIGHT/EARLY
THU MORNING. THE EXCEPTION WILL BE KAVL WHERE GUSTY N WINDS OF
15-20 KTS WILL CONTINUE THROUGH THIS AFTERNOON BEFORE DECREASING TO
AROUND 5-7 KTS OUT OF THE NORTH BY THIS EVENING. SKIES WILL REMAIN
MOSTLY CLEAR THROUGH TONIGHT...WITH HIGH CLOUDS OVERSPREADING THE
REGION BY EARLY TOMORROW MORNING AS AN UPPER SHORTWAVE PASSES NORTH
OF THE AREA.

OUTLOOK...A WEAK UPPER DISTURBANCE WILL SLIDE THROUGH THE REGION ON
THURSDAY WITH LITTLE/NO IMPACT EXPECTED.  ANOTHER MORE ORGANIZED
SYSTEM WILL APPROACH FROM THE WEST FOR THE START OF THE WEEKEND ONCE
AGAIN INCREASING PRECIP/RESTRICTION CHANCES.  SOME WINTRY PRECIP IS
POSSIBLE ACROSS THE NC MOUNTAINS/FOOTHILLS AFFECTING BOTH KAVL AND
KAND SATURDAY MORNING.  WINTRY PRECIP IS NOT EXPECTED AT THIS TIME
FOR ANY OTHER TAF SITES.

CONFIDENCE TABLE...

            18-24Z        00-06Z        06-12Z        12-18Z
KCLT       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAVL       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KHKY       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGMU       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAND       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%

THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)

WWW.WEATHER.GOV/GSP/AVIATION_TABLES

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.

&&

$$
SYNOPSIS...RWH
NEAR TERM...CDG/JOH
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...JOH




AREA FORECAST DISCUSSION

NWS GREENVILLE-SPARTANBURG SC

 936 AM EST WED DEC 17 2014

.SYNOPSIS...
HIGH PRESSURE WILL SPREAD BACK OVER THE REGION TODAY BEHIND A
DEPARTING COLD FRONT. A WEAK WEATHER SYSTEM ALOFT WILL SPREAD CLOUDS
AND PERHAPS SOME SPOTTY LIGHT SHOWERS IN THE MOUNTAINS ON THURSDAY.
ANOTHER LOW WILL DEVELOP TO OUR SOUTHWEST ON FRIDAY AND INCREASE
CHANCES FOR WIDESPREAD PRECIPITATION GOING INTO THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
930 AM EST UPDATE...HAVE DECREASED THE CLOUD COVER OVER PORTIONS OF
THE NC MTNS/VALLEYS PER LATEST VISBY SATELLITE IMAGERY TREND.
OTHERWISE...CURRENT FORECAST REMAINS ON TRACK.

AS OF 600 AM EST WEDNESDAY...LATEST RADAR TRENDS REMAIN RATHER
UNIMPRESSIVE REGARDING POSSIBLE LIGHT SHRA ACROSS THE NORTHERN
MTNS.  THUS POP FCST WILL REMAIN AS IS WHICH FEATURES ALL POPS BEING
REMOVED WITH THE HOUR.  LOW LEVEL STRATUS ACROSS THE MTNS IS STILL
FCST TO SCATTER THROUGH MORNING.  MADE SLIGHT TWEAKS TO TEMPERATURES
AND DEWPOINTS TO REFLECT LATEST OBSERVATIONS.

PREVIOUS DISCUSSION...

AS OF 300 AM EST WEDNESDAY...QUASI ZONAL UPPER FLOW MIGRATING OVER
THE SOUTHEAST WHILE CANADIAN HIGH PRESSURE DIVES SOUTHWARD THROUGH
THE MS RIVER VALLEY INTO THE OH/TN VALLEYS.  MODEST WEST/NORTHWEST
850MB FLOW ALONG THE CENTRAL APPS CONTINUES TO YIELD SCATTERED
SHOWERS ACROSS PORTIONS OF EASTERN KY NORTHWARD INTO WEST VIRGINIA.
ALTHOUGH AMPLE MOISTURE REMAINS FURTHER SOUTH ACROSS PORTIONS OF
WESTERN NC...WEAKER FLOW CONTINUES TO LIMIT COVERAGE.  LATEST
NAM/GFS REMAIN PERSISTENT IN SUGGESTING INCREASING SHOWER COVERAGE
ALONG THE TN LINE NORTH OF INTERSTATE 40 THROUGH MID MORNING.
HOWEVER...HIGH RES GUIDANCE SUCH AS THE HRRR CONTINUES TO BACK OFF.
ALL SAID...WILL KEEP LOW END SLIGHT CHANCE POPS FOR ISOLATED SHOWERS
ACROSS THE NORTHERN MTNS THROUGH 12Z.  FCST DOES FEATURE BRIEF
PERIOD OF FZRA FOR THESE ZONES AS MODEST INVERSION ALOFT SUGGESTS
PRECIP WILL FALL AS LIQUID WITH SOME FREEZING POSSIBLE TOWARD
MORNING LOWS.  NOT EXPECTING ANY SIGNIFICANT IMPACTS BUT CANNOT RULE
OUT A FEW PATCHES OF BLACK ICE.

BEYOND THAT...HIGH PRESSURE WILL PREVAIL ACROSS THE REGION WITH
MOSTLY SUNNY SKIES DOMINATING OVER THE LOW TERRAIN.  DID KEEP
MENTION OF MOSTLY/PARTLY CLOUDY SKIES ACROSS THE HIGH TERRAIN AS
WEAK WESTERLY UPSLOPE FLOW CONTINUES AMONGST SHALLOW MOIST LAYER.
MEANWHILE ANOTHER WEAK UPPER IMPULSE WILL BE SLIDING THROUGH THE
SOUTHERN PLAINS ALLOWING SOME HIGH LEVEL CIRRUS TO MOVE OVER THE
FCST AREA THIS AFTERNOON THROUGH PERIODS END.  DOWNSLOPING FLOW WILL
YIELD NORMAL LEVEL HIGH TEMPERATURES ACROSS THE FOOTHILLS/PIEDMONT
REGIONS WHILE SLIGHTLY BELOW NORMAL HIGHS ARE FCST OVER THE MTNS.
LOWS TONIGHT WILL BE NEAR NORMAL AS ABOVE MENTIONED INCREASING HIGH
LEVEL CIRRUS LIMITS RADIATIONAL COOLING.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 325 AM WEDNESDAY...A WEAK SHORT WAVE WILL MOVE THRU THE ZONAL
FLOW ALOFT THU. THERE IS VERY LITTLE DEEP MOISTURE OR FORCING WITH
THIS SYSTEM. CANNOT RULE OUT A FEW SPRINKLES ACROSS THE NC MTNS
WHERE WLY FLOW MAY BE ABLE TO SQUEEZE THEM OUT OF THE MOISTURE.
THERE SHUD BE QUITE A BIT OF CLOUDS ACROSS THE AREA HOWEVER. SHORT
WAVE RIDGING DEVELOPS AHEAD OF THE NEXT WX SYSTEM APPROACHING FROM
THE SW ON FRI. THIS WILL BRING AN INCREASE IN CLOUDS THRU THE DAY
AFTER THE THU NITE CLEARING FROM THE DEPARTING SHORT WAVE. HIGHS
WILL BE NEAR NORMAL BOTH DAYS...WHILE LOWS THU NITE WILL BE A FEW
DEGREES ABOVE NORMAL.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 355 AM WEDNESDAY...GUIDANCE REMAINS IN GOOD AGREEMENT ON THE
OVERALL PATTERN FOR THE WEEKEND STORM SYSTEM...BUT SOME DIFFERENCES
REMAIN REGARDING THE TEMPERATURE PROFILE AND RESULTING P-TYPES. A
SHORT WAVE APPROACHES THE AREA FRI NITE...MOVES ACROSS THE AREA SAT
AND EAST ON SAT NITE. AT THE SFC...A LOW PRESSURE SYSTEM MOVES EAST
ALONG THE GULF COAST WHILE HIGH PRESSURE SETS UP OVER THE AREA IN A
COLD AIR DAMMING CONFIGURATION. PRECIP CHC INCREASES FROM THE SW FRI
NITE AS MOISTURE MOVES IN AHEAD OF THIS SYSTEM...CAT POP DEVELOPS
ALL AREAS SAT AS THE LOW MOVES SOUTH OF THE AREA...WITH POP SLOWLY
TAPERING OFF SAT NITE AND ENDING ON SUN. THE GFS IS WARMER THAN THE
ECMWF...BUT THE ECMWF IS NOT VERY COLD. USING A BLEND OF THESE TWO
MDLS FOR TEMPS AND THICKNESSES RESULTS IN COLDEST TEMPS AND
THICKNESSES ALONG THE NRN TIER OF THE CWFA...POSSIBLY EXTENDING
SOUTH ALONG THE BLUE RIDGE TO THE SC BORDER. EVEN THEN...P-TYPE
SEEMS TO FAVOR A WINTRY MIX FOR THE NRN BLUE RIDGE AND FREEZING RAIN
EAST AND SOUTH OF THERE. RAIN IS THE P-TYPE FOR MOST OF THE CWFA.
CANNOT RULE OUT ADVISORY LEVEL ICE ACCUMS FOR THE NRN MTN LOCATIONS
LATE FRI NITE AND SAT MORN. HAVE GONE WITH RAIN OR SNOW AS PRECIP
COMES TO AN END SAT NITE AND SUN MORN...BUT THIS AND ANY POTENTIAL
ACCUMS ARE MUCH MORE UNCERTAIN. LOWS WILL BE ABOVE NORMAL FRI AND
SAT NITES...WITH HIGHS SAT 10 DEGREES BELOW NORMAL...RISING TO A FEW
DEGREES BELOW NORMAL ON SUN.

GUIDANCE BEGINS TO DIVERGE FOR THE REST OF THE MEDIUM RANGE. A DEEP
TROF DEVELOPS ACROSS THE CENTRAL CONUS...BUT THE ECMWF IS SLOWER AND
DEEPER WITH THE TROF THAN THE GFS. THE GFS ALSO BRINGS SOME WEAK
SHORT WAVE ENERGY ACROSS THE AREA AHEAD OF THE TROF ON MON...WHILE
THE ECMWF DAMPENS THE WAVE SIGNIFICANTLY. AT THE SFC...THE GFS HAS A
WELL DEFINED LOW PRESSURE SYSTEM WELL SOUTH OF THE AREA ACROSS
FLORIDA AND MOVES IN INTO THE ATLANTIC...KEEPING OUR CWFA RELATIVELY
DRY...WHILE THE ECMWF HAS A LESS DEFINED SFC LOW...BUT A STRONGER
BAROCLINIC ZONE CLOSER TO THE CWFA SPREADING PRECIP IN FROM THE
SOUTH. GIVEN THE DISCREPANCIES...HAVE KEPT MON BASICALLY DRY WITH
TEMPS NEAR NORMAL.

PRECIP SPREADS BACK INTO THE AREA TUE AS A FRONTAL SYSTEM ASSOCIATED
WITH THE UPPER TROF MOVES BACK INTO THE AREA FROM THE WEST.
HOWEVER...DETAILS DIFFER ON EXACT TIMING AND THERMAL STRUCTURE.
THEREFORE...HAVE CHC POP SPREADING IN FROM THE WEST TUE. AGAIN...
GIVEN THE DIFFERENCES...USED RAIN/SNOW FOR THE P-TYPE WHICH WOULD
INDICATE SOME SNOW AT ONSET ACROSS THE NC MTNS...BUT THIS IS ALSO
HIGHLY UNCERTAIN. TEMPS TUE NEAR NORMAL.

&&

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. ZONAL FLOW
ALOFT AND WEAK HIGH PRESSURE AT THE SURFACE WILL KEEP SKIES CLEAR
THROUGH MORNING WITH LIGHT NORTHERLY FLOW.  MODELS CONTINUE TO HINT
AT WEAK LEE TROF DEVELOPMENT BY MID MORNING CAUSING FLOW TO BACK
NEARLY DUE WEST THROUGH THE AFTERNOON.  KEPT WINDS JUST NORTH OF
WEST UNTIL 02Z WHEN CALMING PREVAILS. SKIES WILL SLOWLY FILL IN THIS
AFTERNOON IN THE MID/UPPER LEVELS AS CIRRUS STREAMS IN ALOFT FROM
UPSTREAM MOISTURE PLUME ASSOCIATED WITH WEAK UPPER WAVE.

ELSEWHERE...VERY SIMILAR TO KCLT ABOVE WITH VFR PREVAILING AT ALL
SITES.  SURFACE WINDS WILL VARY ACROSS THE REGION DUE TO LEE TROF
DEVELOPMENT BY LATE MORNING.  ALL SC SITES WILL BE LIGHT/CALM BEFORE
INCREASING OUT OF THE SW BY MID MORNING.  AS FOR THE NC SITES...KAVL
WILL REMAIN NORTHERLY AT   8-10KTS THROUGH THE PERIOD WITH KHKY
GRADUALLY BACKING WESTERLY BY MID/LATE MORNING DUE TO ABOVE
MENTIONED LEE TROF.  FLOW WILL VEER NORTHERLY AT ALL SITES LATE IN
THE DAY WITH MID/HIGH LEVEL CIRRUS STREAMING IN ALOFT LEADING TO
CIGS AT KAVL NEAR THE END OF THE TAF CYCLE.

OUTLOOK...A WEAK UPPER DISTURBANCE WILL SLIDE THROUGH THE REGION ON
THURSDAY WITH LITTLE/NO IMPACT EXPECTED.  ANOTHER MORE ORGANIZED
SYSTEM WILL APPROACH FROM THE WEST FOR THE START OF THE WEEKEND ONCE
AGAIN INCREASING PRECIP/RESTRICTION CHANCES.  SOME WINTRY PRECIP IS
POSSIBLE ACROSS THE NC MOUNTAINS/FOOTHILLS AFFECTING BOTH KAVL AND
KAND SATURDAY MORNING.  WINTRY PRECIP IS NOT EXPECTED AT THIS TIME
FOR ANY OTHER TAF SITES.

CONFIDENCE TABLE...

            14-20Z        20-02Z        02-08Z        08-12Z
KCLT       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAVL       HIGH  96%     HIGH 100%     HIGH 100%     HIGH 100%
KHKY       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGMU       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAND       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%

THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)

WWW.WEATHER.GOV/GSP/AVIATION_TABLES

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.

&&

$$
SYNOPSIS...RWH
NEAR TERM...CDG/JOH
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...CDG



AREA FORECAST DISCUSSION

NWS GREENVILLE-SPARTANBURG SC

 622 AM EST WED DEC 17 2014

.SYNOPSIS...
HIGH PRESSURE WILL SPREAD BACK OVER THE REGION TODAY BEHIND A
DEPARTING COLD FRONT. A WEAK WEATHER SYSTEM ALOFT WILL SPREAD CLOUDS
AND PERHAPS SOME SPOTTY LIGHT SHOWERS IN THE MOUNTAINS ON THURSDAY.
ANOTHER LOW WILL DEVELOP TO OUR SOUTHWEST ON FRIDAY AND INCREASE
CHANCES FOR WIDESPREAD PRECIPITATION GOING INTO THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 600 AM EST WEDNESDAY...LATEST RADAR TRENDS REMAIN RATHER
UNIMPRESSIVE REGARDING POSSIBLE LIGHT SHRA ACROSS THE NORTHERN MTNS.
THUS POP FCST WILL REMAIN AS IS WHICH FEATURES ALL POPS BEING
REMOVED WITH THE HOUR.  LOW LEVEL STRATUS ACROSS THE MTNS IS STILL
FCST TO SCATTER THROUGH MORNING.  MADE SLIGHT TWEAKS TO TEMPERATURES
AND DEWPOINTS TO REFLECT LATEST OBSERVATIONS.

PREVIOUS DISCUSSION...

AS OF 300 AM EST WEDNESDAY...QUASI ZONAL UPPER FLOW MIGRATING OVER
THE SOUTHEAST WHILE CANADIAN HIGH PRESSURE DIVES SOUTHWARD THROUGH
THE MS RIVER VALLEY INTO THE OH/TN VALLEYS.  MODEST WEST/NORTHWEST
850MB FLOW ALONG THE CENTRAL APPS CONTINUES TO YIELD SCATTERED
SHOWERS ACROSS PORTIONS OF EASTERN KY NORTHWARD INTO WEST VIRGINIA.
ALTHOUGH AMPLE MOISTURE REMAINS FURTHER SOUTH ACROSS PORTIONS OF
WESTERN NC...WEAKER FLOW CONTINUES TO LIMIT COVERAGE.  LATEST
NAM/GFS REMAIN PERSISTENT IN SUGGESTING INCREASING SHOWER COVERAGE
ALONG THE TN LINE NORTH OF INTERSTATE 40 THROUGH MID MORNING.
HOWEVER...HIGH RES GUIDANCE SUCH AS THE HRRR CONTINUES TO BACK OFF.
ALL SAID...WILL KEEP LOW END SLIGHT CHANCE POPS FOR ISOLATED SHOWERS
ACROSS THE NORTHERN MTNS THROUGH 12Z.  FCST DOES FEATURE BRIEF
PERIOD OF FZRA FOR THESE ZONES AS MODEST INVERSION ALOFT SUGGESTS
PRECIP WILL FALL AS LIQUID WITH SOME FREEZING POSSIBLE TOWARD
MORNING LOWS.  NOT EXPECTING ANY SIGNIFICANT IMPACTS BUT CANNOT RULE
OUT A FEW PATCHES OF BLACK ICE.

BEYOND THAT...HIGH PRESSURE WILL PREVAIL ACROSS THE REGION WITH
MOSTLY SUNNY SKIES DOMINATING OVER THE LOW TERRAIN.  DID KEEP
MENTION OF MOSTLY/PARTLY CLOUDY SKIES ACROSS THE HIGH TERRAIN AS
WEAK WESTERLY UPSLOPE FLOW CONTINUES AMONGST SHALLOW MOIST LAYER.
MEANWHILE ANOTHER WEAK UPPER IMPULSE WILL BE SLIDING THROUGH THE
SOUTHERN PLAINS ALLOWING SOME HIGH LEVEL CIRRUS TO MOVE OVER THE
FCST AREA THIS AFTERNOON THROUGH PERIODS END.  DOWNSLOPING FLOW WILL
YIELD NORMAL LEVEL HIGH TEMPERATURES ACROSS THE FOOTHILLS/PIEDMONT
REGIONS WHILE SLIGHTLY BELOW NORMAL HIGHS ARE FCST OVER THE MTNS.
LOWS TONIGHT WILL BE NEAR NORMAL AS ABOVE MENTIONED INCREASING HIGH
LEVEL CIRRUS LIMITS RADIATIONAL COOLING.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 325 AM WEDNESDAY...A WEAK SHORT WAVE WILL MOVE THRU THE ZONAL
FLOW ALOFT THU. THERE IS VERY LITTLE DEEP MOISTURE OR FORCING WITH
THIS SYSTEM. CANNOT RULE OUT A FEW SPRINKLES ACROSS THE NC MTNS
WHERE WLY FLOW MAY BE ABLE TO SQUEEZE THEM OUT OF THE MOISTURE.
THERE SHUD BE QUITE A BIT OF CLOUDS ACROSS THE AREA HOWEVER. SHORT
WAVE RIDGING DEVELOPS AHEAD OF THE NEXT WX SYSTEM APPROACHING FROM
THE SW ON FRI. THIS WILL BRING AN INCREASE IN CLOUDS THRU THE DAY
AFTER THE THU NITE CLEARING FROM THE DEPARTING SHORT WAVE. HIGHS
WILL BE NEAR NORMAL BOTH DAYS...WHILE LOWS THU NITE WILL BE A FEW
DEGREES ABOVE NORMAL.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 355 AM WEDNESDAY...GUIDANCE REMAINS IN GOOD AGREEMENT ON THE
OVERALL PATTERN FOR THE WEEKEND STORM SYSTEM...BUT SOME DIFFERENCES
REMAIN REGARDING THE TEMPERATURE PROFILE AND RESULTING P-TYPES. A
SHORT WAVE APPROACHES THE AREA FRI NITE...MOVES ACROSS THE AREA SAT
AND EAST ON SAT NITE. AT THE SFC...A LOW PRESSURE SYSTEM MOVES EAST
ALONG THE GULF COAST WHILE HIGH PRESSURE SETS UP OVER THE AREA IN A
COLD AIR DAMMING CONFIGURATION. PRECIP CHC INCREASES FROM THE SW FRI
NITE AS MOISTURE MOVES IN AHEAD OF THIS SYSTEM...CAT POP DEVELOPS
ALL AREAS SAT AS THE LOW MOVES SOUTH OF THE AREA...WITH POP SLOWLY
TAPERING OFF SAT NITE AND ENDING ON SUN. THE GFS IS WARMER THAN THE
ECMWF...BUT THE ECMWF IS NOT VERY COLD. USING A BLEND OF THESE TWO
MDLS FOR TEMPS AND THICKNESSES RESULTS IN COLDEST TEMPS AND
THICKNESSES ALONG THE NRN TIER OF THE CWFA...POSSIBLY EXTENDING
SOUTH ALONG THE BLUE RIDGE TO THE SC BORDER. EVEN THEN...P-TYPE
SEEMS TO FAVOR A WINTRY MIX FOR THE NRN BLUE RIDGE AND FREEZING RAIN
EAST AND SOUTH OF THERE. RAIN IS THE P-TYPE FOR MOST OF THE CWFA.
CANNOT RULE OUT ADVISORY LEVEL ICE ACCUMS FOR THE NRN MTN LOCATIONS
LATE FRI NITE AND SAT MORN. HAVE GONE WITH RAIN OR SNOW AS PRECIP
COMES TO AN END SAT NITE AND SUN MORN...BUT THIS AND ANY POTENTIAL
ACCUMS ARE MUCH MORE UNCERTAIN. LOWS WILL BE ABOVE NORMAL FRI AND
SAT NITES...WITH HIGHS SAT 10 DEGREES BELOW NORMAL...RISING TO A FEW
DEGREES BELOW NORMAL ON SUN.

GUIDANCE BEGINS TO DIVERGE FOR THE REST OF THE MEDIUM RANGE. A DEEP
TROF DEVELOPS ACROSS THE CENTRAL CONUS...BUT THE ECMWF IS SLOWER AND
DEEPER WITH THE TROF THAN THE GFS. THE GFS ALSO BRINGS SOME WEAK
SHORT WAVE ENERGY ACROSS THE AREA AHEAD OF THE TROF ON MON...WHILE
THE ECMWF DAMPENS THE WAVE SIGNIFICANTLY. AT THE SFC...THE GFS HAS A
WELL DEFINED LOW PRESSURE SYSTEM WELL SOUTH OF THE AREA ACROSS
FLORIDA AND MOVES IN INTO THE ATLANTIC...KEEPING OUR CWFA RELATIVELY
DRY...WHILE THE ECMWF HAS A LESS DEFINED SFC LOW...BUT A STRONGER
BAROCLINIC ZONE CLOSER TO THE CWFA SPREADING PRECIP IN FROM THE
SOUTH. GIVEN THE DISCREPANCIES...HAVE KEPT MON BASICALLY DRY WITH
TEMPS NEAR NORMAL.

PRECIP SPREADS BACK INTO THE AREA TUE AS A FRONTAL SYSTEM ASSOCIATED
WITH THE UPPER TROF MOVES BACK INTO THE AREA FROM THE WEST.
HOWEVER...DETAILS DIFFER ON EXACT TIMING AND THERMAL STRUCTURE.
THEREFORE...HAVE CHC POP SPREADING IN FROM THE WEST TUE. AGAIN...
GIVEN THE DIFFERENCES...USED RAIN/SNOW FOR THE P-TYPE WHICH WOULD
INDICATE SOME SNOW AT ONSET ACROSS THE NC MTNS...BUT THIS IS ALSO
HIGHLY UNCERTAIN. TEMPS TUE NEAR NORMAL.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. ZONAL FLOW
ALOFT AND WEAK HIGH PRESSURE AT THE SURFACE WILL KEEP SKIES CLEAR
THROUGH MORNING WITH LIGHT NORTHERLY FLOW.  MODELS CONTINUE TO HINT
AT WEAK LEE TROF DEVELOPMENT BY MID MORNING CAUSING FLOW TO BACK
NEARLY DUE WEST THROUGH THE AFTERNOON.  KEPT WINDS JUST NORTH OF
WEST UNTIL 02Z WHEN CALMING PREVAILS. SKIES WILL SLOWLY FILL IN THIS
AFTERNOON IN THE MID/UPPER LEVELS AS CIRRUS STREAMS IN ALOFT FROM
UPSTREAM MOISTURE PLUME ASSOCIATED WITH WEAK UPPER WAVE.

ELSEWHERE...VERY SIMILAR TO KCLT ABOVE WITH VFR PREVAILING AT ALL
SITES.  SURFACE WINDS WILL VARY ACROSS THE REGION DUE TO LEE TROF
DEVELOPMENT BY LATE MORNING.  ALL SC SITES WILL BE LIGHT/CALM BEFORE
INCREASING OUT OF THE SW BY MID MORNING.  AS FOR THE NC SITES...KAVL
WILL REMAIN NORTHERLY AT   8-10KTS THROUGH THE PERIOD WITH KHKY
GRADUALLY BACKING WESTERLY BY MID/LATE MORNING DUE TO ABOVE
MENTIONED LEE TROF.  FLOW WILL VEER NORTHERLY AT ALL SITES LATE IN
THE DAY WITH MID/HIGH LEVEL CIRRUS STREAMING IN ALOFT LEADING TO
CIGS AT KAVL NEAR THE END OF THE TAF CYCLE.

OUTLOOK...A WEAK UPPER DISTURBANCE WILL SLIDE THROUGH THE REGION ON
THURSDAY WITH LITTLE/NO IMPACT EXPECTED.  ANOTHER MORE ORGANIZED
SYSTEM WILL APPROACH FROM THE WEST FOR THE START OF THE WEEKEND ONCE
AGAIN INCREASING PRECIP/RESTRICTION CHANCES.  SOME WINTRY PRECIP IS
POSSIBLE ACROSS THE NC MOUNTAINS/FOOTHILLS AFFECTING BOTH KAVL AND
KAND SATURDAY MORNING.  WINTRY PRECIP IS NOT EXPECTED AT THIS TIME
FOR ANY OTHER TAF SITES.

CONFIDENCE TABLE...

            11-17Z        17-23Z        23-05Z        05-06Z
KCLT       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAVL       HIGH  80%     HIGH 100%     HIGH 100%     HIGH 100%
KHKY       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGMU       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAND       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%

THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)

WWW.WEATHER.GOV/GSP/AVIATION_TABLES

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.

&&

$$
SYNOPSIS...RWH
NEAR TERM...CDG
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...CDG



AREA FORECAST DISCUSSION

NWS GREENVILLE-SPARTANBURG SC

 400 AM EST WED DEC 17 2014

.SYNOPSIS...
HIGH PRESSURE WILL SPREAD BACK OVER THE REGION TODAY BEHIND A
DEPARTING COLD FRONT. A WEAK WEATHER SYSTEM ALOFT WILL SPREAD CLOUDS
AND PERHAPS SOME SPOTTY LIGHT SHOWERS IN THE MOUNTAINS ON THURSDAY.
ANOTHER LOW WILL DEVELOP TO OUR SOUTHWEST ON FRIDAY AND INCREASE
CHANCES FOR WIDESPREAD PRECIPITATION GOING INTO THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM EST WEDNESDAY...QUASI ZONAL UPPER FLOW MIGRATING OVER
THE SOUTHEAST WHILE CANADIAN HIGH PRESSURE DIVES SOUTHWARD THROUGH
THE MS RIVER VALLEY INTO THE OH/TN VALLEYS.  MODEST WEST/NORTHWEST
850MB FLOW ALONG THE CENTRAL APPS CONTINUES TO YIELD SCATTERED
SHOWERS ACROSS PORTIONS OF EASTERN KY NORTHWARD INTO WEST VIRGINIA.
ALTHOUGH AMPLE MOISTURE REMAINS FURTHER SOUTH ACROSS PORTIONS OF
WESTERN NC...WEAKER FLOW CONTINUES TO LIMIT COVERAGE.  LATEST
NAM/GFS REMAIN PERSISTENT IN SUGGESTING INCREASING SHOWER COVERAGE
ALONG THE TN LINE NORTH OF INTERSTATE 40 THROUGH MID MORNING.
HOWEVER...HIGH RES GUIDANCE SUCH AS THE HRRR CONTINUES TO BACK OFF.
ALL SAID...WILL KEEP LOW END SLIGHT CHANCE POPS FOR ISOLATED SHOWERS
ACROSS THE NORTHERN MTNS THROUGH 12Z.  FCST DOES FEATURE BRIEF
PERIOD OF FZRA FOR THESE ZONES AS MODEST INVERSION ALOFT SUGGESTS
PRECIP WILL FALL AS LIQUID WITH SOME FREEZING POSSIBLE TOWARD
MORNING LOWS.  NOT EXPECTING ANY SIGNIFICANT IMPACTS BUT CANNOT RULE
OUT A FEW PATCHES OF BLACK ICE.

BEYOND THAT...HIGH PRESSURE WILL PREVAIL ACROSS THE REGION WITH
MOSTLY SUNNY SKIES DOMINATING OVER THE LOW TERRAIN.  DID KEEP
MENTION OF MOSTLY/PARTLY CLOUDY SKIES ACROSS THE HIGH TERRAIN AS
WEAK WESTERLY UPSLOPE FLOW CONTINUES AMONGST SHALLOW MOIST LAYER.
MEANWHILE ANOTHER WEAK UPPER IMPULSE WILL BE SLIDING THROUGH THE
SOUTHERN PLAINS ALLOWING SOME HIGH LEVEL CIRRUS TO MOVE OVER THE
FCST AREA THIS AFTERNOON THROUGH PERIODS END.  DOWNSLOPING FLOW WILL
YIELD NORMAL LEVEL HIGH TEMPERATURES ACROSS THE FOOTHILLS/PIEDMONT
REGIONS WHILE SLIGHTLY BELOW NORMAL HIGHS ARE FCST OVER THE MTNS.
LOWS TONIGHT WILL BE NEAR NORMAL AS ABOVE MENTIONED INCREASING HIGH
LEVEL CIRRUS LIMITS RADIATIONAL COOLING.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 325 AM WEDNESDAY...A WEAK SHORT WAVE WILL MOVE THRU THE ZONAL
FLOW ALOFT THU. THERE IS VERY LITTLE DEEP MOISTURE OR FORCING WITH
THIS SYSTEM. CANNOT RULE OUT A FEW SPRINKLES ACROSS THE NC MTNS
WHERE WLY FLOW MAY BE ABLE TO SQUEEZE THEM OUT OF THE MOISTURE.
THERE SHUD BE QUITE A BIT OF CLOUDS ACROSS THE AREA HOWEVER. SHORT
WAVE RIDGING DEVELOPS AHEAD OF THE NEXT WX SYSTEM APPROACHING FROM
THE SW ON FRI. THIS WILL BRING AN INCREASE IN CLOUDS THRU THE DAY
AFTER THE THU NITE CLEARING FROM THE DEPARTING SHORT WAVE. HIGHS
WILL BE NEAR NORMAL BOTH DAYS...WHILE LOWS THU NITE WILL BE A FEW
DEGREES ABOVE NORMAL.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 355 AM WEDNESDAY...GUIDANCE REMAINS IN GOOD AGREEMENT ON THE
OVERALL PATTERN FOR THE WEEKEND STORM SYSTEM...BUT SOME DIFFERENCES
REMAIN REGARDING THE TEMPERATURE PROFILE AND RESULTING P-TYPES. A
SHORT WAVE APPROACHES THE AREA FRI NITE...MOVES ACROSS THE AREA SAT
AND EAST ON SAT NITE. AT THE SFC...A LOW PRESSURE SYSTEM MOVES EAST
ALONG THE GULF COAST WHILE HIGH PRESSURE SETS UP OVER THE AREA IN A
COLD AIR DAMMING CONFIGURATION. PRECIP CHC INCREASES FROM THE SW FRI
NITE AS MOISTURE MOVES IN AHEAD OF THIS SYSTEM...CAT POP DEVELOPS
ALL AREAS SAT AS THE LOW MOVES SOUTH OF THE AREA...WITH POP SLOWLY
TAPERING OFF SAT NITE AND ENDING ON SUN. THE GFS IS WARMER THAN THE
ECMWF...BUT THE ECMWF IS NOT VERY COLD. USING A BLEND OF THESE TWO
MDLS FOR TEMPS AND THICKNESSES RESULTS IN COLDEST TEMPS AND
THICKNESSES ALONG THE NRN TIER OF THE CWFA...POSSIBLY EXTENDING
SOUTH ALONG THE BLUE RIDGE TO THE SC BORDER. EVEN THEN...P-TYPE
SEEMS TO FAVOR A WINTRY MIX FOR THE NRN BLUE RIDGE AND FREEZING RAIN
EAST AND SOUTH OF THERE. RAIN IS THE P-TYPE FOR MOST OF THE CWFA.
CANNOT RULE OUT ADVISORY LEVEL ICE ACCUMS FOR THE NRN MTN LOCATIONS
LATE FRI NITE AND SAT MORN. HAVE GONE WITH RAIN OR SNOW AS PRECIP
COMES TO AN END SAT NITE AND SUN MORN...BUT THIS AND ANY POTENTIAL
ACCUMS ARE MUCH MORE UNCERTAIN. LOWS WILL BE ABOVE NORMAL FRI AND
SAT NITES...WITH HIGHS SAT 10 DEGREES BELOW NORMAL...RISING TO A FEW
DEGREES BELOW NORMAL ON SUN.

GUIDANCE BEGINS TO DIVERGE FOR THE REST OF THE MEDIUM RANGE. A DEEP
TROF DEVELOPS ACROSS THE CENTRAL CONUS...BUT THE ECMWF IS SLOWER AND
DEEPER WITH THE TROF THAN THE GFS. THE GFS ALSO BRINGS SOME WEAK
SHORT WAVE ENERGY ACROSS THE AREA AHEAD OF THE TROF ON MON...WHILE
THE ECMWF DAMPENS THE WAVE SIGNIFICANTLY. AT THE SFC...THE GFS HAS A
WELL DEFINED LOW PRESSURE SYSTEM WELL SOUTH OF THE AREA ACROSS
FLORIDA AND MOVES IN INTO THE ATLANTIC...KEEPING OUR CWFA RELATIVELY
DRY...WHILE THE ECMWF HAS A LESS DEFINED SFC LOW...BUT A STRONGER
BAROCLINIC ZONE CLOSER TO THE CWFA SPREADING PRECIP IN FROM THE
SOUTH. GIVEN THE DISCREPANCIES...HAVE KEPT MON BASICALLY DRY WITH
TEMPS NEAR NORMAL.

PRECIP SPREADS BACK INTO THE AREA TUE AS A FRONTAL SYSTEM ASSOCIATED
WITH THE UPPER TROF MOVES BACK INTO THE AREA FROM THE WEST.
HOWEVER...DETAILS DIFFER ON EXACT TIMING AND THERMAL STRUCTURE.
THEREFORE...HAVE CHC POP SPREADING IN FROM THE WEST TUE. AGAIN...
GIVEN THE DIFFERENCES...USED RAIN/SNOW FOR THE P-TYPE WHICH WOULD
INDICATE SOME SNOW AT ONSET ACROSS THE NC MTNS...BUT THIS IS ALSO
HIGHLY UNCERTAIN. TEMPS TUE NEAR NORMAL.

&&

.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. ZONAL FLOW
ALOFT AND WEAK HIGH PRESSURE AT THE SURFACE WILL KEEP SKIES CLEAR
AMIDST WNW FLOW THROUGH THE OVERNIGHT.  MODELS HINT AT WEAK LEE TROF
DEVELOPMENT BY MID MORNING ALLOWING FLOW TO BACK ALMOST DUE WEST
THROUGH THE AFTERNOON.  KEPT WINDS JUST NORTH OF WEST UNTIL 02Z WHEN
FLOW VEERS NORTHERLY.  EITHER WAY...WINDS WILL GENERALLY BE LESS
THAN 5KTS.  SKIES WILL INCREASE IN THE MID/UPPER LEVELS AS CIRRUS
STREAMS IN ALOFT FROM UPSTREAM MOISTURE PLUME ASSOCIATED WITH WEAK
UPPER WAVE.

ELSEWHERE...VERY SIMILAR TO KCLT ABOVE WITH VFR PREVAILING AT ALL
SITES WITH THE POSSIBLE EXCEPTIONS BEING AT KAVL AND KHKY. ALL TAFS
INITIALIZE VFR WITH MVFR TEMPOS AT KAVL FOR MVFR LEVEL CIGS
ADVECTING IN FROM THE TN LINE...AND ALSO AT KHKY WHERE GUIDANCE
FAVORS LIGHT PATCHY BR RESTRICTIONS.  OTHERWISE...SOLIDLY VFR WITH
FLOW REMAINING LIGHT AND NORTHERLY THROUGH MORNING BEFORE LEE TROF
BACKS FLOW WESTERLY DURING THE DAY.  FLOW WILL ONCE AGAIN VEER
NORTHERLY LATE IN THE DAY WITH MID/HIGH LEVEL CIRRUS STREAMING IN.

OUTLOOK...A WEAK UPPER DISTURBANCE WILL SLIDE THROUGH THE REGION ON
THURSDAY WITH LITTLE/NO IMPACT EXPECTED.  ANOTHER MORE ORGANIZED
SYSTEM WILL APPROACH FROM THE WEST FOR THE START OF THE WEEKEND ONCE
AGAIN INCREASING PRECIP/RESTRICTION CHANCES.  SOME WINTRY PRECIP IS
POSSIBLE ACROSS THE NC MOUNTAINS/FOOTHILLS AFFECTING BOTH KAVL AND
KAND SATURDAY MORNING.  WINTRY PRECIP IS NOT EXPECTED AT THIS TIME
FOR ANY OTHER TAF SITES.

CONFIDENCE TABLE...

            09-15Z        15-21Z        21-03Z        03-06Z
KCLT       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAVL       MED   75%     HIGH 100%     HIGH 100%     HIGH 100%
KHKY       MED   77%     HIGH 100%     HIGH 100%     HIGH 100%
KGMU       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAND       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%

THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)

WWW.WEATHER.GOV/GSP/AVIATION_TABLES

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.

&&

$$
SYNOPSIS...RWH
NEAR TERM...CDG
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...CDG




AREA FORECAST DISCUSSION

NWS SIOUX FALLS SD

 836 PM CST THU DEC 18 2014

.UPDATE...
ISSUED AT 830 PM CST THU DEC 18 2014

WITH THE CLOUD DECK HANGING IN THE NEIGHBORHOOD OF 1000-1500
FEET...THE CLOUD DECK IS RELATIVELY SHALLOW AND WILL BE DIFFICULT
TO GET DROPLET PRODUCTION. HAVE THEREFORE REMOVED PRECIP THROUGH
THE OVERNIGHT...HOWEVER...AM STILL CONCERNED ABOUT FOG POTENTIAL
ACROSS SOUTH CENTRAL SOUTH DAKOTA. BOTH HI RES HRRR AND THE RAP
SUGGEST FOG POTENTIAL...SO HAVE RAISED FOG MENTION AFTER 06Z
WELL INTO FRIDAY MORNING ALONG THE MISSOURI RIVER VALLEY IN
CENTRAL SOUTH DAKOTA.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 348 PM CST THU DEC 18 2014

STRATUS CURRENTLY COVERING THE ENTIRE REGION...AND THINK THE CLOUDS
STAY LOCKED IN THROUGH THE NIGHT AND INTO TOMORROW. CLEARING LINE IN
CENTRAL SOUTH DAKOTA WILL PROBABLY APPROACH OUR FAR WESTERN AREAS
SUCH AS GREGORY AND BRULE COUNTIES. SO COULD SEE SOME CLEARING THERE
LATER TONIGHT...AND SOME SUN IN THOSE LOCATIONS TOMORROW. THIS IS
THE AREA THAT COULD SEE SOME FOG DEVELOPMENT LATER TONIGHT IF THEY
ARE ABLE TO CLEAR...SO ADDED IN FOG MENTION. THE REST OF THE AREA
WILL STAY LOCKED IN THE LOW CLOUDS THROUGH TOMORROW...WITH NOTHING
ABLE TO SCOUR OUT THE LOW LEVEL MOISTURE. GIVEN THE CLOUD
COVER...RAISED LOWS TONIGHT...AS DO NOT THINK TEMPERATURES WILL BE
ABLE TO FALL MORE THAN A FEW DEGREES FROM CURRENT READINGS.

ONE QUESTION IS WHETHER WE ARE ABLE TO GET ANY FLURRIES OUT OF THE
STRATUS TONIGHT. MODELS SUGGEST MOISTURE LAYER DEEPENS ENOUGH FOR
THIS TO BE A POSSIBILITY...BUT MOISTURE DEPTH AND SATURATION BOTH
SEEM BORDERLINE. EXPECT CLOUD TOP TEMPERATURES TO BE RIGHT AROUND
-7C TO -10C...RIGHT ON THE EDGE OF ICE PRODUCTION. THUS CAN NOT RULE
OUT A LITTLE LIGHT FREEZING DRIZZLE AS WELL. MOISTURE DEPTH LOOKS TO
DECREASE FROM WEST TO EAST THROUGH THE NIGHT...SO THINK THE LIGHT
PRECIP THREAT SHOULD WANE BY MORNING. WILL NEED TO KEEP AN EYE ON
THINGS...BUT AT THIS TIME THINK THAT EVEN IF WE DO GET FREEZING
DRIZZLE...IT WILL NOT BE HEAVY ENOUGH TO CAUSE MUCH OF AN ISSUE.
OTHERWISE CLOUDY BUT SLIGHTLY WARMER CONDITIONS TOMORROW. CLOUDS
WILL PREVENT US FROM WARMING TOO MUCH...BUT STILL THINKING WE GET
INTO THE LOW TO MID 30S.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 348 PM CST THU DEC 18 2014

MOIST LOW LEVEL FLOW WILL CONTINUE TO BRING LOW STRATUS TO THE BULK
OF THE FORECAST AREA FRIDAY NIGHT THROUGH SATURDAY NIGHT. SOME
DECEASE IN CLOUD COVERAGE WILL BE POSSIBLE ON SATURDAY...
PARTICULARLY IN THE WEST WHERE TEMPERATURES WILL QUICKLY WARM INTO
THE MID AND UPPER 30S AND MAY SOAR EVEN HIGHER IF SUBSTANTIAL
CLEARING DOES OCCUR. WITHOUT MUCH LIFT IN THE CLOUD
LAYER...MEASURABLE PRECIPITATION IS NOT EXPECTED. CANNOT RULE OUT
SOME PATCHY DRIZZLE/FREEZING DRIZZLE POTENTIAL...BUT WITH CLOUD TOPS
TOO WARM FOR ICE CRYSTAL GROWTH...FLURRIES ARE NOT EXPECTED. MODEL
SOUNDINGS SUGGEST THAT THE CLOUD DEPTH IS A BIT TOO MARGINAL FOR
WIDESPREAD DRIZZLE OR FREEZING DRIZZLE...WITH THE EXCEPTION OF PARTS
OF NORTHWEST IOWA ON SATURDAY NIGHT. SURFACE TEMPERATURES WILL BE IN
THE UPPER 20S AT THIS TIME...SO WILL LEAVE MENTION OF PATCHY
FREEZING DRIZZLE.

POTENT STORM SYSTEM BEGINS TAKING SHAPE OVER THE NORTHERN PLAINS
SUNDAY AFTERNOON AS A TROUGH EMERGES FROM THE CANADIAN ROCKIES AND
DIGS INTO NORTH DAKOTA. STILL LOOKING AT SOME FAIRLY SIGNIFICANT
MODEL DIFFERENCES REGARDING THE TRACK AND TIMING...SO CONFIDENCE IN
TEMPERATURE TRENDS AND PRECIPITATION TIMING IS SOMEWHAT LOW. IT DOES
LOOK LIKE AN INITIAL WAVE SWINGS INTO THE AREA SUNDAY NIGHT...WITH
THE GEM AND NAM AROUND 6 TO 12 HOURS FASTER THAN THE ECMWF AND GFS.
WITH THIS WAVE SOME BROAD LIFT NOSES INTO THE AREA AND SHOULD ALLOW
SOME LIGHT PRECIPITATION TO FORM MAINLY ACROSS THE EASTERN HALF.
SURFACE TEMPERATURES COOL WHILE THE MILD AIR ALOFT ERODES. EXPECT A
WINTRY MIX OF PRECIPITATION...WITH SNOW...SLEET AND FREEZING RAIN
POSSIBLE. WITH THE BETTER FORCING LIKELY TO OUR EAST...ANY
PRECIPITATION WILL BE VERY LIGHT AND PRELIMINARILY IT LOOKS LIKE
SNOW AND ICE AMOUNTS WOULD BE VERY MINIMAL.

SECONDARY WAVE FOLLOWS QUICKLY ON MONDAY...SLOWS AND DEEPENS OVER
THE MID AND NORTHERN MISSISSIPPI VALLEY INTO MONDAY NIGHT. THE GEM
IS THE OUTLIER WITH A WEAKER OPEN WAVE AND WAS THEREFORE DISCARDED.
THE LATEST GFS AND ECMWF ARE QUITE A BIT FURTHER EAST WITH THE LOW
CENTER COMPARED TO PREVIOUS RUNS. IT SLOWLY WOBBLES OFF TO THE EAST
THROUGH TUESDAY NIGHT WITH LIGHT PRECIPITATION IMPACTING OUR AREA ON
THE BACK SIDE OF THE LOW. WITH A MORE EASTERN TRACK...THE BEST
POTENTIAL FOR PRECIPITATION FOR US WILL BE ACROSS OUR EASTERN HALF
MONDAY INTO TUESDAY. COOLER AIR ADVECTING INTO THE AREA BEHIND THE
LOW WILL ALLOW THE RAIN AND SNOW MIX ON MONDAY TO SWITCH ENTIRELY TO
SNOW MONDAY NIGHT. WINDS WILL ALSO PICK UP FROM THE NORTHWEST MONDAY
NIGHT AND TUESDAY AND BECOME QUITE BREEZY. HIGHS ON MONDAY WILL BE
MILD IN THE 30S...AND COOL SLIGHTLY INTO THE UPPER 20S TO MID 30S ON
TUESDAY.

STRATUS CLOUDS STICK AROUND THE REGION WEDNESDAY WITH ANOTHER
POSSIBLE WEAK WAVE DIVING ALONG THE UPPER LEVEL NORTHWEST FLOW.
SLIGHT CHANCE OF LIGHT SNOW WILL ACCOMPANY THIS WAVE ACROSS OUR
NORTHEASTERN HALF. COOLER TEMPERATURES FILTER BACK INTO THE REGION
MID WEEK DROPPING READINGS BACK BELOW NORMAL.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 459 PM CST THU DEC 18 2014

CLOUDS LOOK TO PREVAIL THROUGH THE OVERNIGHT HOURS...LIKELY MVFR
TO IFR AT TIMES. THE BACK EDGE OF THE STRATUS WILL APPROACH KHON
AFTER MIDNIGHT...WITH SHORT TERM GUIDANCE SUGGESTING THAT FOG WILL
DEVELOP ON THE BACK EDGE OF THE STRATUS. WILL INCLUDE A PERIOD OF
LIFR FOG FOR HON THAT SHOULD LIFT INTO AN ADDITIONAL STRATUS LAYER
INTO FRIDAY.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

UPDATE...
SHORT TERM...CHENARD
LONG TERM...
AVIATION...DUX



AREA FORECAST DISCUSSION

NWS LUBBOCK TX

 1157 PM CST TUE DEC 16 2014

.DISCUSSION...
SHORT TERM SOLUTIONS HAVE TRENDED A LITTLE DRIER IN CRITICAL MID
LAYER OF ATMOSPHERE...AND THUS HAVE BACKED OFF SOMEWHAT ON SHOWER
PROSPECTS SPREADING INTO KLBB AND KPVW JUST AFTER DAYBREAK
WEDNESDAY. WE WILL NOT INCLUDE SHOWER MENTION FOR THIS VERSION OF
THE TAF. FOR KCDS...SOLUTIONS NOT IN GOOD ENOUGH AGREEMENT ON
SHOWER PROSPECTS THERE AS WELL FOR LATER ON WEDNESDAY ALTHOUGH
BETTER CHANCE FOR BEING NEARBY. STILL...WITHHOLDING SHOWERS FROM
KCDS AS WELL. OTHERWISE EXPECT MVFR CEILINGS TO TAKE HOLD FOR BOTH
KPVW AND KLBB EARLY IN THE MORNING AND NOT LET GO UNTIL EARLY OR
MID AFTERNOON. MVFR MORE OF AN OUTSIDE RISK FOR KCDS...BUT BETTER
IF SHOWERS DO COME TOGETHER AFTER ALL. RMCQUEEN

&&

.PREV DISCUSSION... /ISSUED 524 PM CST TUE DEC 16 2014/

AVIATION...
LOW LEVEL MOISTURE EXPANDING NORTH A LITTLE AHEAD OF SCHEDULE
LEADING TO A DECK NEAR 4000 FEET ABOVE THE GROUND AT KLBB AND SOON
TO SPREAD TO KPVW. SATELLITE AND RAP SOLUTIONS SUGGEST THERE MAY
BE A BREAK SKIRTING CLOSE TO BOTH KLBB AND KPVW BY MID EVENING BUT
UNCLEAR IF CEILING WILL BREAK...CHOSE TO KEEP A CONSTANT LAYER FOR
NOW. THIS LAYER SHOULD SPREAD INTO KCDS AS WELL BY MID EVENING.
SATELLITE SHOWS A WELL DEFINED IMPULSE CROSSING NORTHERN BAJA
CALIFORNIA AT THIS TIME AND NOW FORECAST TO LIFT INTO THE WESTERN
SOUTH PLAINS BY MID TO LATE WEDNESDAY MORNING. BOTH RAP AND
WRF/NAM NOW DEPICT MODEST ISENTROPIC LIFT AND LOWERING OF CLOUD
DECKS FOR KPVW AND KLBB NEAR OR JUST AFTER SUNRISE WEDNESDAY...AS
WELL AS SHOWERS DEVELOPING NEARBY. WE WILL WATCH SOLUTION TRENDS
ON THIS AND DECIDE BY THE 06Z TAF IF SHOWERS AND A CLOUD DECK
LOWERING TO NEAR THE BOTTOM OF MVFR LEVELS WORTHY TO INCLUDE FOR
THE NEXT ISSUANCE. RMCQUEEN

PREV DISCUSSION... /ISSUED 300 PM CST TUE DEC 16 2014/

SHORT TERM...
INCREASING LOW LEVEL MOISTURE ADVECTION AHEAD OF AN UPPER TROUGH...
LOCATED JUST OFF THE SRN CALI/BAJA CALI COAST AS OF EARLY AFTN...TO
SPREAD STRATUS ACROSS THE FCST OVERNIGHT. THIS MAY END UP OCCURRING
MORE QUICKLY THAN PREVIOUSLY ANTICIPATED AS A BATCH LOW CLOUDS
CONTINUES TO MOVE NWD THROUGH THE PERMIAN BASIN WITH LITTLE HINT
ATTM OF DISSIPATING THIS AFTN. THE MAIN UPPER TROUGH PROGGED TO HOLD
BACK ACROSS THE WRN CONUS INTO WEDNESDAY NIGHT BEFORE DAMPENING
SIGNIFICANTLY AND EJECTING EWD THURSDAY. BEFORE THEN AN INITIAL
SHORT WAVE TROUGH PROGGED TO EJECT ACROSS THE HIGH PLAINS AND AS
THIS UPPER TROUGH APPROACHES CHANCES FOR LIGHT RAIN SHOWERS WILL
INCREASE. WRF-NAM AND ITS ASSOCIATED MOS GUIDANCE WITH POPS CLOSER
TO 30 PCT NOT COMPLETELY UNFOUNDED...BUT APPEARS TO PLAY INTO THE
MODEL BIAS OF OVERPRODUCING LIGHT PRECIP WITH ABUNDANT LOW LEVEL
MOISTURE IN PLACE. ALSO...LAST SEVERAL SYSTEMS HAVE BEEN
DISAPPOINTMENTS RELATIVE TO THE MODEL PROGS AND MOS OUTPUT. THAT
SAID...PREVIOUS FCST LOOKS FINE ATTM WITH SLIGHT CHANCE POPS EAST
AFTER 12Z WEDNESDAY. TEMPS A LESSER CONCERN WITH A RELATIVELY MILD
NIGHT NEAR OR JUST ABOVE MOS LOOKING GOOD. HIGHS WEDNESDAY A BIT
TRICKY AND WILL DEPEND MUCH ON HOW QUICKLY SKIES CLEAR BEHIND THE
TROUGH. SOME SORT OF BLEND BETWEEN MET AND MAV MOS NUMBERS WITH A
SLIGHT NUDGE TO THE WARMER END IS REASONABLE ATTM.

LONG TERM...
A NEG TILTED SHORTWAVE WILL BE POSITIONED OVER THE FA EARLY THURSDAY
WITH MOST OF ITS ENERGY PLACED JUST TO OUR EAST. THE SHORTWAVE WILL
BE QUICKLY KICKED OUT OF THE AREA BY AN APPROACHING TROF FROM THE
WEST. OVERALL MODELS CONTINUE TO HAVE A LESS AMPLIFIED TROF BY
FRIDAY WITH THE EXCEPTION OF THE NAM AND CMC WHICH HAVE A DEEPER AND
SHARPER TROF. MINUS THE CMC...THE GLOBAL MODELS APPEAR TO BE
HANDLING THE TROF BETTER IN THE SYNOPTIC SCALE. THE BIGGER
DIFFERENCES ARE WITH MOISTURE RETURN/AVAILABILITY. THE GFS IS
SOMEWHAT OF AN OUTLIER HAVING A DRY FORECAST DESPITE TROPICAL
MOISTURE FLOWING IN FROM THE PACIFIC. FOR NOW POPS HAVE BEEN KEPT IN
FOR FRIDAY AS LIFT AND MOISTURE SHOULD BE SUFFICIENT ENOUGH FOR
PRECIP. ONE OF THE BIGGER QUESTIONS FOR THIS PERIOD IS PRECIP TYPE.
MOST OF THE FA SHOULD SEE LIQUID PRECIP. THE EXCEPTION TO THAT WOULD
BE ACROSS OUR NORTHWESTERN ZONES WHERE FORECAST SOUNDINGS SHOW TEMPS
ALOFT COOLING ENOUGH TO PRODUCE SNOW AS THE AXIS OF THE TROF MOVES
OVERHEAD FRIDAY MORNING. SURFACE TEMPS SHOULD DROP TO BELOW FREEZING
BY THIS TIME...HOWEVER LITTLE TO NO ACCUMULATION WOULD BE EXPECTED
AS SOIL TEMPS WOULD HAVE NO TIME TO RESPOND AND WOULD STAY ABOVE
FREEZING. THIS TROF WILL QUICKLY PUSH EAST BY SATURDAY WHILE ANOTHER
TROF...THIS ONE DEEPER THAN ITS PREDECESSOR...MOVES INTO THE REGION.
SOME SHOWERS WILL STILL BE POSSIBLE SUNDAY NIGHT WITH THIS SYSTEM
BUT WOULD MOST LIKELY BE LIGHT AS LIFT WILL BE RELATIVELY WEAK DUE
TO THE POS TILT OF THE TROF. THE TROF WILL GIVE WAY TO NORTHWESTERLY
FLOW BY EARLY NEXT WEEK WHICH SHOULD HELP KEEP TEMPS AROUND SEASONAL
AVERAGE.

&&

.PRELIMINARY POINT TEMPS/POPS...
FRIONA        28  53  30  53  29 /  10  10   0  10  30
TULIA         32  48  33  51  31 /  10  10   0  10  30
PLAINVIEW     32  50  33  54  32 /  10  10   0  10  30
LEVELLAND     35  57  33  58  32 /  10  10   0  10  30
LUBBOCK       35  55  35  58  34 /  10  10   0  10  30
DENVER CITY   36  58  35  60  35 /  10  10   0  10  30
BROWNFIELD    36  57  35  59  34 /  10  10   0  10  30
CHILDRESS     33  47  36  53  36 /  10  20  10  10  30
SPUR          35  51  37  59  35 /  10  20  10  10  40
ASPERMONT     38  52  39  62  38 /  10  20  10  10  40

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

99/99/05






AREA FORECAST DISCUSSION

NWS CHEYENNE WY

 1046 PM MST TUE DEC 16 2014

.UPDATE...
ISSUED AT 813 PM MST TUE DEC 16 2014

LATEST RADAR LOOP SHOWS A BAND OF LIGHT SNOW SHOWERS LIFTING INTO
THE SOUTHERN NE PANHANDLE FROM NORTHEAST CO. THIS APPEARS TO BE
ASSOCIATED WITH A WEAK MIDLVL DISTURBANCE TRAVERSING THE CENTRAL
HIGH PLAINS ATTM. WITH SOME BANDING OWING TO WEAK FRONTOGENESIS
AROUND H7...COULD SEE A DUSTING OF SNOW ALONG AND SOUTH OF THE I80
CORRIDOR IN NE TONIGHT. ADDED A SLIGHT CHANCE OF SNOW THROUGH 06Z
WED. FOG IS STILL A CONCERN FOR THE OVERNIGHT HOURS. LOWEST VSBYS
SO FAR HAVE BEEN ALONG THE PLATTE RIVER WITH MOIST UPVALLEY WINDS
OUT OF THE EAST/SOUTHEAST. THESE AREAS SAW THE MOST SNOW WITH THE
RECENT STORM AS WELL...SO THERE IS PLENTY OF BLYR MOISTURE TO GO
AROUND. THE HRRR STILL SUGGESTS PATCHY FOG WILL LIKELY EXPAND TO
OTHER PARTS OF EAST CENTRAL WY AND THE WESTERN PANHANDLE
OVERNIGHT...EXCEPT ADJACENT TO THE LARAMIE RANGE WHERE THE LLVLS
SHOULD STAY MORE MIXED. LIGHT WEST WINDS AND AMPLE LLVL MOISTURE
COULD RESULT IN PATCHY FOG WEST OF THE LARAMIE RANGE AS WELL.
INCREASED TEMPERATURES A FEW DEGREES OVER THE PANHANDLE WITH LOW
STRATUS MINIMIZING THE POTENTIAL FOR RADIATIONAL COOLING. ONLY
OTHER CHANGES WERE TO ADJUST SKY TRENDS AND THE TIMING/INTENSITY
OF FOG.

&&

.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 243 PM MST TUE DEC 16 2014

TONIGHT...MOST WIDESPREAD CHALLENGE WILL BE FOG
DEVELOPMENT...INCLUDING AREAL COVERAGE AND VISIBILITIES. WHERE FOG
WAS SLOWEST TO ERODE...FROM TORRINGTON...TO SCOTTSBLUFF AND TO
ALLIANCE...INCLUDING OVER THE SNOWFIELD...3 PM TEMPERATURE AND
DEWPOINT SPREADS ARE ONLY 2 TO 5 DEGREES WITH CLEARING MID LEVEL
SKIES NOTED ON VISIBLE SATELLITE IMAGERY...THUS EXPECT FOG TO
DEVELOP RATHER QUICKLY AND SPREAD OVER AFOREMENTIONED LOCALES IN
THE LATE AFTERNOON AND EARLY EVENING HOURS.

LOW LEVELS AND BOUNDARY LAYER SATURATE UP DECENTLY
OVERNIGHT...ESPECIALLY OVER OUR WESTERN COUNTIES OF CARBON AND
ALBANY...AND MID AFTERNOON TEMPERATURE DEWPOINT SPREADS ARE ONLY
AROUND 7 DEGREES AT RAWLINS AND LARAMIE...ALONG WITH MID LEVEL
CLEARING PROGGED...THUS EXPECT RATHER EXTENSIVE FOG TO DEVELOP LATE
THIS EVENING AND OVERNIGHT ACROSS OUR WESTERN COUNTIES.

NEGATIVELY TILTED SHORTWAVE TROUGH ALOFT MOVES FROM WESTERN WYOMING
THIS AFTERNOON...TO NORTHWEST WYOMING BY MIDNIGHT AND TO CENTRAL
MONTANA BY DAYBREAK...BASED ON SATELLITE AND RADAR TRENDS...EXPECT
INCREASING AREAL COVERAGE OF SNOW SHOWERS THIS EVENING ACROSS OUR
WYOMING COUNTIES...ESPECIALLY OVER AND NEAR THE SNOWY AND SIERRA
MADRE RANGES...WITH A SLOW CESSATION AND DECREASE IN AREAL SNOW
COVERAGE LATE THIS EVENING AND OVERNIGHT. MAY EVEN SEE A FEW
FLAKES ALONG AND EAST OF INTERSTATE 25...THOUGH COVERAGE LOOKS
QUITE MINIMAL.

WEDNESDAY...SPLIT TROUGHS ALOFT MOVE ACROSS OUR REGION WITH THE
BULK OF SNOW AND DEEPER MOISTURE LOCATED OVER COLORADO...THOUGH
OUR SNOWY AND SIERRA MADRE RANGES WILL SEE SCATTERED OROGRAPHIC
SNOW SHOWERS...MOSTLY DRY ELSEWHERE.

WEDNESDAY NIGHT...NORTHERN STREAM SHORTWAVE TROUGH ALOFT MOVES OVER
THE WESTERN DAKOTAS...WITH THE SOUTHERN STREAM SHORTWAVE TROUGH
ALOFT MOVING OVER WESTERN KANSAS...THUS MINIMAL COVERAGE OF SNOW
SHOWERS OVER OUR COUNTIES...MAINLY OVER THE SNOWY AND SIERRA MADRE
RANGES...DRY ELSEWHERE.

THURSDAY...PSEUDO CYCLONIC FLOW ALOFT CONTINUES OVER OUR COUNTIES
WITH ONE SHORTWAVE ALOFT OVER THE FOUR CORNERS WITH MOST OF THAT
SHORTWAVE TROUGH SNOW OVER WESTERN COLORADO...THOUGH WILL SEE SOME
OROGRAPHIC SNOW SHOWERS OVER OUR SNOWY AND SIERRA MADRE RANGES...
DRY ELSEWHERE.

THURSDAY NIGHT...FAST MOVING...MOISTURE STARVED SHORTWAVE TROUGH
ALOFT MOVES ACROSS OUR COUNTIES...THOUGH WITH MINIMAL LOW AND MID
LEVEL MOISTURE...ONLY SOME ISOLATED MOUNTAIN SNOW SHOWERS ON TAP.

.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 243 PM MST TUE DEC 16 2014

SHORTWAVE TROUGH WILL MOVE OVERHEAD ON FRIDAY UNDER WEAK NORTHWEST
FLOW. MODELS KEEP THE HIGHEST LLVL MOISTURE OVER THE MOUNTAINS THRU
THE DAY WHICH IS REASONABLE IN THIS FLOW PATTERN...SO KEPT SNOW
CHANCES CONFINED TO THE SNOWY AND SIERRA MADRES MOUNTAINS. ANOTHER
WEAK SHORTWAVE TROUGH WILL MOVE THROUGH ON SATURDAY/SATURDAY NIGHT
WITH A SLIGHTLY MORE NORTHERLY TRACK...SO COULD SEE LIGHT SNOW
SHOWERS RETURNING TO THE MOUNTAINS INCLUDING THE NORTHERN LARAMIE
RANGE THROUGH THIS TIME. WINDS ALOFT WILL BEGIN TO INCREASE SUNDAY
AND MONDAY AS A STRONG EASTERN PAC HIGH BUILDS IN FROM THE WEST. THE
STORM TRACK WILL THUS SHIFT OVER THE NORTHERN ROCKIES AND HIGH
PLAINS THROUGH THE EARLY PART OF THE WEEK...WITH WINDY CONDITIONS
AND INCREASING COVERAGE OF SNOW SHOWERS EXPECTED. THE NOSE OF A 150+
KT JET WILL MOVE OVERHEAD MONDAY...WITH A RATHER VIGOROUS VORT MAX
MOVING FROM THE NORTHERN ROCKIES INTO THE CENTRAL PLAINS IN THE LFQ
REGION OF THE JET. STILL LOOKS FAVORABLE FOR MORE WIDESPREAD SNOW
SHOWERS OVER THE CWA ON MONDAY...ESPECIALLY OVER THE MOUNTAINS AND
NORTHERN PLAINS FROM DOUGLAS TO ALLIANCE IN BETTER PROXIMITY TO THE
JET DIFLUENCE AND LIFT FROM THE VORT MAX. THE LLVL GRADIENT WILL
INCREASE IN ADVANCE OF THE WAVE AS THE LEESIDE TROUGH DEEPENS AS
WELL...SO SHOULD ALSO SEE WINDS BECOME MODERATE TO STRONG LATE
SUNDAY THROUGH MONDAY. THE ASSOCIATED COLD FRONT WILL MOVE ACROSS
THE EASTERN PLAINS SOMETIME LATE MONDAY...AND SHOULD STALL HERE
THROUGH TUESDAY. WINDY CONDITIONS WITH CHANCES FOR LIGHT SNOW WILL
CONTINUE OVER THE MOUNTAINS WITH RAIN/SNOW MIX OVER THE PLAINS AS A
RESULT. TEMPS THROUGH THE PERIOD WILL REMAIN AROUND NORMAL FOR THIS
TIME OF YEAR...WITH A SLIGHT BUMP UPWARDS AS DOWNSLOPE WINDS KICK IN
FOR MONDAY AND TUESDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1040 PM MST TUE DEC 16 2014

LOW STRATUS AND PATCHY FOG WILL CONTINUE TO BE THE MAIN AVIATION
HAZARD THIS TAF PERIOD. MVFR TO IFR CIGS/VSBYS ARE POSSIBLE THRU
THE NIGHT...MAINLY OVER THE NEBRASKA TERMINALS. THERE MAY BE A
BRIEF PERIOD OF IMPROVING CONDITIONS AROUND 15-18Z BEFORE MOISTURE
INCREASES AGAIN IN THE AFTERNOON. IFR CIGS COULD REMAIN IN PLACE
OVER KAIA THROUGH WED NIGHT.

&&

.FIRE WEATHER...
ISSUED AT 243 PM MST TUE DEC 16 2014

MINIMAL ISSUES DUE TO PROJECTED HUMIDITIES AND WINDS.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

UPDATE...CLH
SHORT TERM...RUBIN
LONG TERM...RJM
AVIATION...CLH
FIRE WEATHER...RUBIN





AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 301 AM CST FRI DEC 19 2014

.SHORT TERM...
259 AM CST

THROUGH SUNDAY...

THE MAIN CONCERNS DURING THE SHORT TERM WILL BE SOME PERIODIC
CHANCES OF VERY LIGHT SNOW OR DRIZZLE THROUGH THE WEEKEND AS SEVERAL
WEAK...AND FAST MOVING MID LEVEL DISTURBANCES SHIFT ACROSS THE AREA.

SURFACE HIGH PRESSURE IS CENTERED ACROSS MUCH OF THE MID AND UPPER
MISSISSIPPI RIVER VALLEY EARLY THIS MORNING. THIS FEATURE IS EXPECTED
TO REMAIN IN CONTROL ACROSS NORTHERN ILLINOIS DURING THE DAY TODAY.
OVERALL...WITH WILL RESULT IN A VERY LIGHT AND VARIABLE WIND FIELD
ACROSS THE AREA TODAY. AN AREA OF LAKE EFFECT FLURRIES CONTINUES
ACROSS PORTIONS OF THE CHICAGO AREA...AND INTO NORTHWESTERN INDIANA
NEAR LAKE MICHIGAN. MODEL SOUNDINGS INDICATE JUST DEEP ENOUGH
INVERSION HEIGHTS TO SUPPORT ICE IN THE CLOUDS...AND GIVEN MDW HAS
BEEN REPORTING ONLY -SN FOR MOST OF THE NIGHT IT APPEARS THE THREAT
OF FREEZING DRIZZLE WILL BE LOW. ALL OF THIS ACTIVITY SHOULD WANE
ACROSS THE AREA DURING THE MORNING AS THE WIND FIELD CONTINUES TO
WEAKEN OVER SOUTH LAKE MICHIGAN IN RESPONSE TO THE APPROACHING
SURFACE RIDGE OF HIGH PRESSURE.

SURFACE WINDS WILL BEGIN TO SHIFT OUT OF THE SOUTH BY EARLY SATURDAY
MORNING AS THIS SURFACE HIGH BEGINS TO SHIFT EAST OF THE REGION. AS
THIS OCCURS...GUIDANCE IS INSISTENT WITH BRINGING A WEAK UPPER
DISTURBANCE ACROSS NORTHERN ILLINOIS SATURDAY MORNING. THIS WEAK
WAVE IS NOTED IN THE WATER VAPOR IMAGERY CURRENTLY ACROSS
SOUTHEASTERN ALBERTA. MOISTURE APPEARS TO REMAIN LIMITED WITH THIS
WAVE. HOWEVER...I THINK THIS WAVE...AND SOME WEAK ISENTROPIC ASCENT
COULD SQUEEZE OUT A FEW FLURRIES SATURDAY MORNING...SO I HAVE
INCLUDED A SLIGHT CHANCE FOR SUCH IN THE FORECAST.

WARM AIR ADVECTION/ISENTROPIC ASCENT WILL CONTINUE TO INCREASE
ACROSS MUCH OF THE MIDWEST AND GREAT LAKES REGION INTO SUNDAY IN
RESPONSE TO AN INCREASING SOUTHERLY WIND FIELD AHEAD OF A STORM
SYSTEM...WHICH IS EXPECTED TO DEVELOP ACROSS THE PLAINS. THIS COULD
AGAIN RESULT IN A PERIOD OF LIGHT PRECIP ACROSS MAINLY FAR NORTHERN
ILLINOIS VERY LATE SATURDAY NIGHT AND INTO SUNDAY.
OVERALL...CONFIDENCE IS LOW AS TO HOW FAR SOUTH THIS LIGHT PRECIP
WILL BE ABLE TO DEVELOP...BUT GIVEN THE POTENTIAL THAT IF THIS
PRECIP DOES DEVELOP AS FAR SOUTH AS NORTHERN ILLINOIS...THERE COULD
BE A PERIOD OF FREEZING DRIZZLE INTO EARLY SUNDAY MORNING BEFORE
TEMPERATURES JUMP ABOVE FREEZING...I HAVE OPTED TO INCLUDE A SLIGHT
MENTION LATE SATURDAY NIGHT INTO EARLY SUNDAY...MAINLY FOR AREAS
NORTH OF INTERSTATE 90.

KJB

&&

.LONG TERM...
259 AM CST

SUNDAY NIGHT THROUGH THURSDAY...

THE LONG TERM PERIOD WILL BE A PERIOD OF A SIGNIFICANT WEATHER
PATTERN SHIFT ACROSS NORTH AMERICA AND AS SUCH...IT APPEARS LIKELY
THAT THE CENTRAL CONUS WILL BECOME MUCH MORE ACTIVE INTO THE
HOLIDAY WEEK. THE MAIN CONCERNS LOCALLY WITH THIS PATTERN
SHIFT...WILL BE PRECIP TYPES...AND THE ACTUAL EVOLUTION
OF...POTENTIALLY A SIGNIFICANT STORM SYSTEM ACROSS PORTIONS OF THE
GREAT LAKES REGION CHRISTMAS EVE.

UNFORTUNATELY...THE DETAILS OF THIS STORM SYSTEM THIS FAR OUT ARE
STILL LARGELY UNCERTAIN...AS LARGE SCALE PATTERN SHIFTS SUCH AS THIS
TYPICAL RESULT IN LOWER PREDICTABILITY...ESPECIALLY WITH REGARDS TO
THE TRACK AND ACTUAL STRENGTH OF A DEVELOPING STORM SYSTEM. WHAT
APPEARS TO BE LIKELY...HOWEVER...IS FOR A PERIOD OF RAIN ACROSS THE
AREA LATE MONDAY AND MONDAY NIGHT AS WHAT APPEARS TO BE THE INITIAL
STORM SYSTEM...BEGINS TO SHIFT A WARM FRONT ACROSS NORTHERN
ILLINOIS. GIVEN THE WARM SECTOR PLACEMENT OF MY AREA...PRECIP TYPE
LOOKS TO BE LIQUID...WITH SURFACE TEMPERATURES LIKELY TO REMAIN
ABOVE FREEZING MONDAY NIGHT WITH CONTINUED SOUTHERN FLOW.

THE MAIN UNCERTAINTIES COME INTO PLAY BY CHRISTMAS EVE...AS MODEL
GUIDANCE CONTINUES TO ADVERTISE A SIGNIFICANT AMPLIFICATION TO THE
UPPER LEVEL PATTERN ACROSS THE EASTERN PACIFIC AND NORTH AMERICA. A
STRONG PACIFIC JET (NEAR 40 DEGREES N)...INITIALIZED AT OVER 180 KT
IN THIS EVENINGS MODEL OUTPUT IS FORECAST TO RESULT IN THE BUILDING
OF A POTENT UPPER RIDGE JUST OFF THE CALIFORNIA COAST BY EARLY NEXT
WEEK. TELECONNECTIONS RELATED TO SUCH PATTERN SHIFT CERTAINLY SUPPORT
THE DIGGING OF A SIGNIFICANT TROUGH...AND A GOOD POSSIBILITY OF AN
STORM SYSTEM ACROSS THE CENTRAL CONUS DURING THE UPCOMING HOLIDAY
WEEK. HOWEVER...AS PREVIOUSLY MENTIONED CONFIDENCE IS LOW WITH THE
DETAILS OF HOW AND WHERE EXACTLY THIS STORM MAY TRACK. THIS IS A
PERIOD WORTH WATCHING THOUGH...AS AT LEAST SOME SNOW AND POSSIBLY
STRONG NORTHWEST WINDS COULD BE IN STORE.

KJB

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 06Z...

* BRIEF PERIOD OF FLURRIES/VERY LIGHT SNOW PRE-DAWN. MDW MAY SEE
  VIS REDUCED BRIEFLY TO MVFR.

* MVFR CEILINGS TO PERSIST MUCH OF PERIOD...LIFTING NEAR VFR OR
  POSSIBLY SCATTERING OUT FOR A TIME MID-MORNING THROUGH THIS
  AFTERNOON.

* LIGHT WINDS 5 KT OR LESS. STARTING WEST-NORTHWEST EARLY THIS
  MORNING...LIKELY VARIABLE OR CALM LATER TODAY/THIS EVENING.

RATZER

//DISCUSSION...UPDATED 06Z...

KLOT/TORD AND TMDW RADARS INDICATING SOME WEAK RETURNS OVER
SOUTHERN LAKE MICHIGAN AND THE IMMEDIATE METRO AREAS AT 0530Z.
THESE RETURNS ASSOCIATED WITH LIGHT LAKE-EFFECT PRECIP IN THE
FORM OF LIGHT SNOW...OR FREEZING DRIZZLE. WEB-CAMS FROM DOWNTOWN
INDICATE SOME DROP IN VISIBILITY WITH PRECIP...WHICH RADAR
INDICATES WILL LIKELY AFFECT METRO TERMINALS FOR A TIME EARLY THIS
MORNING. MID-LEVEL DISTURBANCE PASSING 12-15Z SHOULD ALLOW
INVERSION HEIGHTS OVER THE LAKE TO LOWER...WHICH ALONG WITH
WEAKENING LOW LEVEL WIND FIELD SHOULD END PRECIP.

OTHERWISE...EXTENSIVE AREA OF MVFR CIGS REMAINS TRAPPED BENEATH
SHALLOW INVERSION ASSOCIATED WITH WEAK SURFACE HIGH PRESSURE
ACROSS THE REGION...THOUGH SATELLITE IMAGERY DOES SHOW SOME
EROSION/CLEARING OVER PARTS OF EAST CENTRAL AND NORTHEAST WI AS
WELL AS A CORRIDOR ALONG A MLI-PNT-DNV-LAF LINE. SOME INDICATIONS
EXIST THAT THIS CLEARING OVER PARTS OF WI WILL CONTINUE TO WORK
SOUTH-SOUTHWEST ALONG THE WESTERN SHORE OF LAKE MICHIGAN LATER
THIS MORNING AND COULD SCATTER OUT MVFR CLOUDS FOR A TIME LATE
THIS MORNING INTO THIS AFTERNOON. MODEL GUIDANCE IS A LITTLE MORE
PESSIMISTIC BUT DOES ALSO HINT AT RAISING CEILINGS OR SCATTERING
LOW CLOUDS AS WELL.

LIGHT NORTHWEST OR WEST-NORTHWEST WINDS 5 KT OR LESS THIS MORNING
SHOULD BECOME VARIABLE OR CALM LATER TODAY INTO THIS EVENING AS
THE CENTER OF THE WEAK AND DIFFUSE SURFACE HIGH DRIFTS EAST ACROSS
THE TERMINALS. WEAK SOUTH-SOUTHWEST FLOW DEVELOPS JUST ABOVE THE
SURFACE THIS EVENING...FROM WHICH GUIDANCE SUPPORTS A REDEVELOPMENT
OF MVFR CIGS WITH SLOW LOW-LEVEL MOISTENING.

RATZER

//ORD AND MDW CONFIDENCE...UPDATED 06Z...

* MEDIUM-HIGH IN CEILING TRENDS...AND BRIEF LIGHT SNOW EARLY THIS
  AM.

* HIGH IN WINDS.

RATZER

//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z...

* SATURDAY AND SUNDAY...DRY/VFR. LIGHT SOUTH WINDS.
* MONDAY...CHANCE OF RAIN/SNOW. MVFR LIKELY. GUSTY SOUTHERLY WINDS.
* TUESDAY...CHANCE OF RAIN/SNOW. IFR LIKELY. SOUTHWEST WINDS.
* WEDNESDAY...CHANCE OF SNOW. MVFR LIKELY. STRONG/GUST WEST WINDS.

BEACHLER

&&

.MARINE...
156 AM CST

MAIN MARINE CONCERNS THIS MORNING ARE A PERIOD OF STRENGTHENING
SOUTH-SOUTHEAST WINDS LATE SUNDAY THROUGH MONDAY NIGHT...THEN THE
POTENTIAL FOR WEST GALES LATE WEDNESDAY INTO THURSDAY.

FAIRLY QUIET STRETCH OF WEATHER ACROSS LAKE MICHIGAN TODAY THROUGH
SATURDAY AS A LARGE AREA OF WEAK HIGH PRESSURE DRIFTS SLOWLY EAST
ACROSS THE REGION. LIGHT NORTH WINDS TODAY WILL BECOME SOMEWHAT
LIGHT/VARIABLE...BEFORE BECOMING LIGHT SOUTH ON SATURDAY AS THE
SURFACE RIDGE AXIS PASSES TO THE EAST. SOUTHERLY WINDS WILL THEN
BEGIN TO INCREASE SATURDAY NIGHT AND MORE SO SUNDAY...AS LOW
PRESSURE DEVELOPS IN THE LEE OF THE NORTHERN ROCKIES AND THE
GRADIENT BEGINS TO TIGHTEN ACROSS THE PLAINS AND UPPER MIDWEST.
MEDIUM RANGE FORECAST MODELS ARE IN GENERAL AGREEMENT IN DEVELOPING
A SUB-1000 MB SURFACE LOW ACROSS IOWA OR SOUTHERN MINNESOTA BY
MIDDAY MONDAY...WHICH WOULD LEAD TO SOUTH-SOUTHEAST WINDS IN THE
20-25 KT RANGE THROUGH MONDAY BEFORE OCCLUDING AND WEAKENING AS THE
LOW MOVES ACROSS WISCONSIN AND LAKE MICHIGAN ON TUESDAY.

HOWEVER...VARIOUS MODEL AND MODEL ENSEMBLE MEMBERS THEN DEVELOP A
SECOND LOW SOUTH OF THE LAKES ALONG THE TRAILING COLD FRONT TUESDAY
NIGHT...WHICH WOULD LIFT NORTH AND COMBINE WITH THE FILLING GREAT
LAKES LOW...DEEPENING RAPIDLY WEDNESDAY AND WEDNESDAY NIGHT OVER THE
EASTERN LAKES. THIS SCENARIO WOULD LEAD TO QUICKLY INCREASING
WESTERLY WINDS ACROSS LAKE MICHIGAN...QUITE POSSIBLY WEST GALES...
LATE WEDNESDAY INTO THURSDAY/CHRISTMAS DAY AS THE LOW PULLS AWAY TO
THE NORTHEAST.

RATZER

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$

VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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  [top]

Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
241 AM CST Fri Dec 19 2014

.SHORT TERM...(Today)
ISSUED AT 240 AM CST FRI DEC 19 2014

High pressure is expected to hold over central Illinois through
today with the next southern stream shortwave, currently over south
central Texas early this morning, forecast to track well south of
our area. 2am satellite data and surface observations showing an
area of clear skies extending from just northwest of Peoria
southeast thru Champaign and Decatur. Short range models suggest
this area will gradually fill back in with clouds as the day wears
on. Forecast soundings from the HRRR and Rapid Refresh models also
support this idea thru the day with the last few satellite frames
off the IR loop indicating the clouds over far west central IL were
starting to shift more to the east. Forecast soundings across
central IL today support afternoon temperatures in the low to mid
30s with another day with very little wind, something that is a bit
on the rare side for December across our area.


&&

.LONG TERM...(Tonight through Christmas Day)
ISSUED AT 240 AM CST FRI DEC 19 2014

Main focus remains with active pattern setting up for the upcoming
holiday week.

Powerful jet of 120-160 knots at 300 mb will be coming into the
Pacific Northwest later this weekend before diving toward the
southern Plains, helping to carve out a deep trough over the central
U.S. The GFS and ECMWF models are in good agreement with development
of a closed low over eastern South Dakota by midday Monday, with
some minor disagreements as to the amount of wobbling of this low as
it drifts toward the east. The ECMWF brings the center as far south
as Springfield by Wednesday morning, while the GFS and Canadian
models are centered across Wisconsin.

Precipitation shield with this system expected to start spreading
into the Illinois River valley by late Monday morning, then eastward
across the state during the day. The GFS is more prominent with a
dry slot punching in already by late evening, while the ECMWF
lingers the rain into Tuesday morning. Leaned more towards the
slower ECMWF solution and increased rain chances to around 60%
Monday night north of I-74 and east of I-57. Forecast soundings are
well above freezing up to around 850 mb, so have removed any mixed
precip wording for Monday night. Some mixture possible northwest of
the Illinois River on Tuesday, although a loss of ice crystals aloft
with the dry slot may mitigate this.

As we head toward Christmas Eve, amount of wrap-around precipitation
is a concern. The ECMWF rapidly intensifies the surface cyclone to
our east, with central pressure down to around 978 mb midday near
Cleveland. This solution brings periodic snow showers southeast into
our area in the strong northwest flow. The much weaker GFS has some
flurries lingering through the day, with less windy conditions. Have
kept precipitation chances across the east during the day on the
edge of the ECMWF`s dry slot, but kept only slight chances elsewhere
for now. Snowfall amounts still appear to be on the light side, but
holiday travel will still not be pleasant with the snow and the
winds. Christmas Day itself appears dry.


&&

.AVIATION...(For the 06Z TAFS through 06Z Friday night)
ISSUED AT 1118 PM CST THU DEC 18 2014

VFR conditions should last through the TAF period. Some clearing
has developed along the surface ridge axis over some of the TAF
sites already...but decided to keep few or scattered clouds since
confidence is not strong enough in clear skies over a long period
of time. Satellite shows a relatively narrow band of
clearing...with more cloud cover upstream. Winds will be calm to
light throughout the TAF period as the surface high stays over
central Illinois through tomorrow evening before slowly shifting
eastward. Winds will be variable with the high overhead and will
shift to the east southeast tomorrow night...but remain light.


&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Smith
LONG TERM...Geelhart
AVIATION...ALW







AREA FORECAST DISCUSSION

NWS DES MOINES IA

 1148 PM CST THU DEC 18 2014

.SHORT TERM /TONIGHT/...
ISSUED AT 324 PM CST THU DEC 18 2014

SNOW HAS ENDED OVER THE SOUTHEASTERN CWA AS THE CULPRIT UPPER LEVEL
WAVE HAS RAPIDLY WEAKENED AND DGZ FORCING HAS WANED. BASED ON WEBCAM
IMAGES AND A FEW SPOTTER/COOP REPORTS...MOST AREAS IN THE SOUTHERN
THREE TIERS OF COUNTIES SAW LESS THAN AN INCH OF SNOW. ATTENTION NOW
TURNS UPSTREAM TO A LARGE STRATUS PLUME STRETCHING FROM NORTHWEST
MONTANA TO THE TEXAS PANHANDLE...WITH THE EASTERN FRONT NOW JUST
ABOUT TO ENTER THE WESTERN CWA. LIGHT WEST TO SOUTHWEST FLOW IN THE
LOWEST 1 KM OF THE ATMOSPHERE BEHIND A DEPARTING SURFACE RIDGE
SHOULD ADVECT THIS CLOUD MASS OVER CENTRAL IOWA TONIGHT AND KEEP
SKIES OVERCAST ALL NIGHT AND INTO TOMORROW MORNING. THE CLOUDS
SHOULD ALSO BOLSTER LOW TEMPS TONIGHT COMPARED TO PREVIOUS NIGHTS
AND DIDN`T DEVIATE MUCH FROM GUIDANCE IN THIS RESPECT.

THE BIGGEST UNCERTAINTY FOR TONIGHT IS THE POSSIBILITY OF FLURRIES
OR FREEZING DRIZZLE WEST OF I-35. SHORT-RANGE MODEL SOUNDINGS (RUC
AND HRRR IN PARTICULAR) SATURATE THE LOWEST 5 KFT OF THE ATMOSPHERE
IN THIS REGION TONIGHT WITH NEARLY ISOTHERMAL PROFILES IN THIS LAYER
HOVERING BETWEEN -4 AND -7C. WITH THIS CONDITIONAL ICE PROBABILITY
...WENT WITH A MIX OF OCCASIONAL FLURRIES AND PATCHY FZDZ. FORCING
SHOULD BE MARGINAL AT BEST AND NO ACCUMULATION OF SNOW OR ICE IS
ANTICIPATED. ANY LIFT WITH AN UPPER LEVEL TROUGH ON WATER VAPOR
IMAGERY NW OF THE CWA SHOULD STAY NORTH AND EAST OF THE AREA.
ISENTROPIC UPGLIDE IN THE LOWEST 100MB OF THE ATMOSPHERE IS
PRESENT...BUT AGAIN VERY WEAK.

.LONG TERM /FRIDAY THROUGH THURSDAY/...
ISSUED AT 324 PM CST THU DEC 18 2014

THE WEATHER IN THE LONG TERM WILL IN GENERAL BE MORE ACTIVE THEN
WHAT WE HAVE SEEN IN A WHILE.  FRIDAY THROUGH SUNDAY THERE WILL BE
NUMEROUS RELATIVELY WEAK SHORT WAVES MOVE ACROSS IOWA IN A GENERALLY
ZONAL FLOW.  THROUGH SATURDAY MOISTURE WILL EITHER BE SPARSE OR
SHALLOW SO I AM NOT EXPECTING MUCH WITH THESE SHORTWAVES IN TERMS OF
SENSIBLE WEATHER EXCEPT FOR CLOUD COVER.  TEMPS SHOULD BE RATHER
MILD FOR MID TO LATE DECEMBER.

SATURDAY NIGHT THROUGH SUNDAY A LITTLE STRONGER SHORT WAVE MOVES IN
AND MOISTURE DEPTH INCREASES SLIGHTLY ALTHOUGH IT IS STILL VERY
SHALLOW.  SOUNDINGS DO NOT INDICATE ICE INTRODUCTION AND WHILE THERE
ARE MODEL DIFFERENCES AS TO WHERE ANY WEAK FORCING MIGHT OCCUR...IT
DOES APPEAR THAT THE NORTHERN HALF OF IOWA IS MORE LIKELY TO SEE
THIS THAN SOUTHERN IOWA.  AS A RESULT I KEPT THE MENTION OF FREEZING
DRIZZLE CONFINED TO THE NORTH.  THE SOUNDING DOES SATURATE
OR BEGIN TO SATURATE SUFFICIENTLY LATE SATURDAY NIGHT THROUGH
SUNDAY MORNING THROUGH THE DENDRITIC ZONE THAT WE COULD TRANSITION
TO SOME LIGHT SNOW UP NORTH...ESPECIALLY SUNDAY MORNING. THAT
SHORTWAVE EXITS DURING THE EARLY AFTERNOON AND TEMPS WARM
SUFFICIENTLY FOR A WINTERY MIX CHANGING TO RAIN ACROSS AT LEAST
SOME OF THE AREA.

SUNDAY NIGHT THROUGH MONDAY A MORE POTENT SHORTWAVE MOVES INTO
IOWA...AFFECTING THE WEST SUNDAY NIGHT AND THE REST OF THE AREA
THROUGH TUESDAY.  HERE MODELS DIVERGE ON HOW TO HANDLE THIS SYSTEM.
THE GFS KEEP THE UPPER LEVEL WAVE OPEN AND DEVELOPS A CLOSED SURFACE
LOW OVER CENTRAL TO NORTHEAST IOWA.  THE EURO DRASTICALLY DEPEND
THE UPPER WAVE TO OUR WEST THEN CONTINUES TO DEVELOP IT INTO A
CLOSED LOW MONDAY NIGHT AND TUESDAY ACROSS EASTERN IOWA.  THE
RESULTANT CLOSED SURFACE LOW IS OVER EASTERN IOWA AS WELL AND
FURTHER SOUTHWEST THAN THE GFS HAS.  THE GFS REALLY DEVELOPS THE QG
FORCING ACROSS CENTRAL IOWA SUNDAY NIGHT THEN IS SIGNIFICANTLY
WEAKER THROUGH TUESDAY.  SOUNDINGS SHOW A PROFILE THAT IS PRETTY
WARM THROUGH MONDAY AFTERNOON WHEN THE PROFILE COOLS TO BELOW
FREEZING.  PRECIP THROUGH EARLY MONDAY AFTERNOON SHOULD BE RAIN WITH
AN OCCASIONAL WINTERY MIX ESPECIALLY UP NORTH.  DURING THE AFTERNOON
WE WILL BE TRANSITIONING TO A RAIN/SNOW MIX BEFORE GOING TO ALL SNOW
MONDAY NIGHT.  IT IS TOO FAR OUT TO CONSIDER SNOWFALL AMOUNTS YET
AND GIVEN THE MODEL DISCREPANCIES IT WOULD BE HARD TO DO AT THIS
POINT.

THAT SYSTEM PULLS OUT BY CHRISTMAS EVE LEAVING US WITH SEASONAL
TEMPS AND MAINLY DRY.  ANOTHER SYSTEM PUSHES IN FOR THURSDAY NIGHT
AND FRIDAY AND GIVEN THE STRENGTH OF THE TROUGH OVER US THAT FAR OUT
WE WILL GET SOME PRECIP OUT OF THE SYSTEM BUT MODEL DISCREPANCIES
ARE TOO BIG TO GIVE MUCH IN THE WAY OF TIMING AND AMOUNT DETAILS.

&&

.AVIATION...19/06Z
ISSUED AT 1141 PM CST THU DEC 18 2014

LOW STRATUS WILL CONTINUE TO BE WIDESPREAD FOR THE DURATION OF THE
FORECAST. VFR CONDITIONS WILL PERSIST ACRS THE FAR NORTHEAST
THROUGH MUCH OF THE NIGHT BUT THE SLOW NORTH AND EAST PROGRESSION
OF MVFR TO IFR CEILINGS WILL CONTINUE AS SOUTHERLY FLOW BEGINS TO
INCREASE AS SURFACE RIDGE SLIDES SLOWLY EASTWARD. THE MVFR TO IFR
CONDITIONS WILL PERSIST INTO FRIDAY AND FRIDAY EVENING AS THE
MOIST LOW LEVEL FLOW CONTINUES. GFS IS INDICATING SOME -DZ/-FZDZ
BY AFTERNOON ACROSS PORTIONS OF THE FORECAST AREA AS FORCING
INCREASES. HAVE NOT INCLUDED AT THIS TIME BUT WILL HAVE TO BE
MONITORED FOR INCLUSION IN SUBSEQUENT FORECASTS. SURFACE WINDS
WILL BE LIGHT OVERNIGHT BECOMING SOUTHEAST TO SOUTH ON FRIDAY BUT
REMAINING LIGHT.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...SKOW
LONG TERM...FAB
AVIATION...COGIL



AREA FORECAST DISCUSSION...CORRECTED

NWS GOODLAND KS

 234 AM MST FRI DEC 19 2014

.SHORT TERM...(THIS MORNING THROUGH SUNDAY NIGHT)
ISSUED AT 233 AM MST FRI DEC 19 2014

EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW SHORTWAVE
TROUGH OVER OK PANHANDLE WITH SHORTWAVE RIDGE OVER THE TREAT BASIN
BUILDING EAST TOWARDS THE CENTRAL ROCKIES. AT THE SURFACE...LOW
PRESSURE REMAINS IN PLACE FROM THE NORTHERN PLAINS AND ACROSS
EASTERN COLORADO. HIGH PRESSURE IS GENERALLY IN PLACES ACROSS MUCH
OF THE CWA...WITH LOW PRESSURE BEGINNING TO BUILD IN FROM THE WEST.

EARLY THIS MORNING...AXIS OF DENSE FOG DEVELOPED LATE LAST NIGHT
GENERALLY ALONG HWY 25 AND HWY 83 CORRIDOR BEHIND STRATUS DECK TO
THE EAST. WEST OF THIS...BL HAS BEEN TOO DRY FOR DENSE FOG
DEVELOPMENT...THOUGH WITH NEARBY HIGH PRESSURE/LIGHT WINDS/CLEAR
SKIES PATCHY FOG WILL BE POSSIBLE THIS MORNING. RAP/HRRR BOTH HAVE
GOOD REFLECTION OF THE SPOTTY NATURE OF THE FOG OVER OUR CWA...AND
GENERALLY KEEP MAIN AXIS OF DENSE FOG WHERE IT IS...IMPROVING
CONDITIONS AROUND 12-13Z. DUE TO THE LOCALIZED NATURE OF THE
DENSE FOG AND GUIDANCE TRENDING AWAY FROM WIDESPREAD COVERAGE I
DECIDED TO CONTINUE WITH HANDLING THIS EVENT WITH SPS.

TODAY...ANY FOG/STRATUS SHOULD CLEAR BY MIDDAY AS SURFACE LOW SHIFTS
EAST TO THE KS/CO BORDER. THIS WILL SUPPORT TEMPS MODERATING TO THE
40S/NEAR 50 OVER MUCH OF THE CWA (COOLER IN YUMA COUNTY WHERE SNOW
PACK LINGERS).

TONIGHT-WE MAY SEE FOG REDEVELOP ACROSS NORTH CENTRAL KS...WHICH
COULD IMPACT OUR EASTERN CWA. THOUGH NAM/SREF HAVE A PRETTY GOOD
SIGNAL FOR THIS...AS LOW SHIFTS EAST AIR MASS WILL BE CHANGING WITH
LOWER BL MOISTURE PRESENT AND IM NOT AS SURE CURRENT MODEL
COVERAGE/DEPICTION IS REALISTIC. I ADDED PATCHY FREEZING FOG IN OUR
EAST AHEAD OF MAIN SURFACE TROUGH TO COVER POTENTIAL.

SATURDAY-SUNDAY...SHORTWAVE RIDGE WILL TRANSITION EASTWARD ACROSS
THE PLAINS SATURDAY/SATURDAY NIGHT WITH A TROUGH REDEVELOPING OVER
THE NORTHERN PLAINS BY SUNDAY NIGHT. AHEAD OF THIS DEVELOPING UPPER
TROUGH...SURFACE TROUGHING AND INCREASING WAA WILL SUPPORT
INCREASING TEMPS TO WELL ABOVE NORMAL. DEPENDING ON MIXING (WHICH
COULD BE LIMITED BY CLOUDS)...HIGHS BY SUNDAY SHOULD BE IN MIDDLE
50S WITH DECREASING IMPACT FROM SNOW PACK IN THE NORTHWEST AS IT
CONTINUES TO DEGRADE OVER THE NEXT FEW DAYS. I COULD ACTUALLY SEE
SOME LOCATIONS APPROACH THE UPPER 50S SUNDAY BASED ON CURRENT
925/850 MB TEMPS.

SUNDAY NIGHT...LOBES OF MID LEVEL VORTICITY COMBINED WITH INCREASING
FRONTOGENETIC FORCING COULD SUPPORT SEVERAL BANDS OF LIGHT
PRECIPITATION MOVING INTO OUR CWA BY SUNDAY NIGHT. MODELS ARE
SHOWING A GOOD DRY LAYER THAT ANY PRECIP WOULD HAVE TO SATURATE
THROUGH. TEMP PROFILES GENERALLY SUPPORT RAIN...WITH SATURATION TO
WET BULB TEMPS NEAR A RAIN OR RAIN/SNOW MIX LATE SUNDAY NIGHT. DUE
TO UNCERTAINTY OF MEASURABLE DUE TO DRY LAYER AND POSITION OF
THESE BANDS...I KEPT POP MENTION LIMITED TO SLIGHT CHANCE.

.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 233 AM MST FRI DEC 19 2014

AN UPPER LEVEL TROUGH WILL MOVE THROUGH THE CENTRAL PLAINS REGION
MONDAY...BRINGING CHANCES FOR RAIN AND SNOW SHOWERS.  BASED ON THE
LOWER LEVEL TEMPERATURE FIELD...CRITICAL THICKNESSES AND WET BULB
ZERO HEIGHTS...EXPECTING NORTHWEST PORTIONS OF THE FORECAST AREA TO
START AS A RAIN/SNOW MIX.  OTHERWISE...ALL OTHER AREAS WILL RECEIVE
RAIN MONDAY MORNING.  ALTHOUGH THERE IS STRONG NORTHWEST FLOW ALOFT
WITH COOLER TEMPERATURES BEING ADVECTED INTO THE AREA...SURFACE
TEMPERATURES WILL WARM INTO THE MID TO UPPER 40S IN THE AFTERNOON.
THIS SURFACE WARMING WILL ALLOW RAIN TO BE THE PRIMARY PRECIPITATION
TYPE IN THE AFTERNOON.  PRECIPITATION WILL CHANGE BACK TO SNOW AFTER
SUNSET.  ECMWF AND GFS MODELS ARE FORECASTING BETWEEN 1 AND 2 INCHES
OF SNOW...HOWEVER CONFIDENCE IS LOW IN THOSE FORECAST AMOUNTS DUE TO
RUNNING ACCUMULATIONS IN PERIODS OF PHASE CHANGE. THEREFORE...THE
FORECAST REFLECTS TOTAL VALUES LESS THAN AN INCH AT THIS TIME.

A SHORTWAVE RIDGE WILL BUILD INTO THE TRI STATE AREA TUESDAY AND
WEDNESDAY...BRINGING DRY CONDITIONS AND NEAR NORMAL HIGH
TEMPERATURES IN THE LOW TO UPPER 40S.  BLENDED POP FORECAST WAS
HINTING AT PRECIPITATION CHANCES THROUGH THE DAY TUESDAY...BUT
DECIDED TO ELIMINATE POPS DUE TO THE 500 MB AXIS BEING THROUGH THE
FORECAST AREA BY 18Z TUESDAY.

THE NEXT WEATHER SYSTEM TO APPROACH THE REGION WILL COME FROM THE
PACIFIC NORTHWEST CHRISTMAS EVE THROUGH CHRISTMAS DAY.  ALTHOUGH
THIS SYSTEM IS STILL A FEW DAYS OUT...GUIDANCE IS SEEMINGLY SLOWING
THE PROGRESSION OF THE SYSTEM INTO THE AREA TOWARDS A THURSDAY NIGHT
OR FRIDAY ARRIVAL. A GENERAL NORTHWEST FLOW WILL BRING MOISTURE IN
FROM THE PACIFIC NORTHWEST MAINLY ON THE NORTHERN COLD SIDE OF THE
SURFACE LOW...WHICH WILL BRING CHANCES FOR SNOW SHOWERS.  AT THIS
TIME...THINKING A LITTLE OVER AN INCH CAN BE EXPECTED FOR AREAS
NORTH OF INTERSTATE 70.  THIS AMOUNT IS LIKELY TO CHANGE WITH FUTURE
FORECASTS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1037 PM MST THU DEC 18 2014

FOR KGLD THRU 13Z FRIDAY VFR/MVFR MIX WITH 3-6SM IN FOG WITH
BKN060 AND KMCK...THRU 15Z FRI...WILL HAVE A MIX OF IFR AND BELOW
AS FOG WILL BRING VISIBILITY RANGING 2SM DOWN TO 1/4SM AT TIMES
AND CEILINGS RANGING FROM OVC002-010. BUT AFT 13Z-15Z THIS MORNING
BOTH SITES VFR WITH SCT100-150. WINDS VARIABLE AN LIGHT THRU 13Z-
15Z...THEN WSW 5-10KTS.


&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

$$

SHORT TERM...DR
LONG TERM...MK
AVIATION...JN



AREA FORECAST DISCUSSION

NWS TOPEKA KS

 248 AM CST Fri Dec 19 2014

.SHORT TERM...(Today and Tonight)
Issued at 246 AM CST FRI DEC 19 2014

08Z water vapor imagery indicated there were a couple waves within a
somewhat slow split flow over the plains. The stronger wave was
lifting through the southern plains with some decent lightning noted
in eastern TX. A second weaker wave was noted over southeastern MT.
At the surface a high pressure system centered over the central and
upper MS river valley was nosing into eastern KS with a ridge axis
bisecting the forecast area.

For today and tonight, the better forcing from the shortwaves looks
to only glance the forecast area. Forecast soundings from the
RAP/NAM/GFS indicated a decent amount of dry air in the mid levels
and prog a westerly wind at 850 and above to continue advecting dry
air in from the west. So with the weak forcing unlikely to overcome
the dry air in mid levels, have maintained a dry forecast through
tonight. Really the main forecast challenge is the boundary layer
moisture and pesky stratus. All the models fall to mix out the low
level inversion and the boundary layer moisture. This seems to make
some since with the expansive stratus deck already in place and snow
cover limiting any insolation to warm surface temps. Therefore have
leaned towards an overcast sky through tonight. Isentropic surfaces
show only weak if any isentropic upglide and appear to focus this
mainly across MO, so concerns for drizzle are minimal today as well.
About the only uncertainty with the forecast is the NAM`s tendency
to over due the impact of the snow cover and keeping the boundary
layer to cool for to long. However with the GFS and RAP showing
similar solutions, think the low clouds scattering out is a low
chance occurrence. Highs today are expected to be in the mid 30s
with no real low level warm air advection and clouds holding on
strong. For tonight have kept skies cloudy, but if for some reason
we were to clear out, fog would become more likely. I don`t have a
lot of confidence in this happening. Nevertheless have added a
mention of patchy fog after midnight due to forecast soundings
showing the potential for some fog, especially across north central
KS. Lows tonight are expected to range from the mid 20 to around 30.

.LONG TERM...(Saturday through Thursday)
Issued at 246 AM CST FRI DEC 19 2014

Patchy fog is expected to linger through mid morning Saturday before
lifting to mostly cloudy stratus. A developing surface trough over
eastern CO will pick up winds around 10 mph, attempting to mix out
the stratus in the lower levels. Best chances for seeing peeks of
sunshine lie across central KS, with much of the CWA remaining
cloudy. Despite the warmer temps from guidance, believe the
lingering snow cover holds highs a few degrees cooler in north
central and far northeast KS where upper 30s are common. Areas with
little to no snow cover may reach the lower to middle 40s. Surface
trough begins to deepen on Sunday in response to the upper shortwave
trough coming onshore from the Pacific NW. Southwesterly winds
increase around 15 mph through the afternoon. A weaker lead trough
progresses over the northern plains Sunday morning, bringing a
chance for light drizzle. Freezing precip should not be a concern as
guidance is trending warmer near 40 degrees for morning lows.
Precip chances increase Sunday evening into Monday as the system
shifts east over the northern plains. Discrepancies remain on
guidance as the latest ECMWF is less amplified and impacting more
of the eastern CWA, similar to the GEM. In addition, the GFS is
more amplified from an upper jet streak rounding the southern edge
of the wave. Given this and the amount of saturation is relative
compared to previous systems, will continue with 30-40 pops until
more consistency is seen between runs. Bulk of the QPF is rain on
Monday as highs peak in the upper 40s. The freezing temps slide in
behind the departing wave where a rain and snow mix is possible
Monday evening. No accumulation is expected at this time.

An anomalous upper ridge builds eastward into the region Tuesday and
Wednesday giving the area a chance to clear out the stratus clouds.
Modified airmass in the wake of the system will only drop highs into
the low 40s for highs and lows in the upper 20s and low 30s. In
terms of Christmas Day, much uncertainty exists with the timing and
track of the next upper trough. Latest runs are trending slower with
the system, GFS being more progressive and impacting mainly north
central areas. Meanwhile the ECMWF is slower and places our area in
the dry slot. While confidence is below average, will maintain
forecast consistency with slight chances for a rain and snow mix.

&&

.AVIATION...(For the 06Z TAFs through 06Z Friday Night)
Issued at 1120 PM CST THU DEC 18 2014

Low stratus of 600 to 900 feet will continue across the terminals
for most of the next 24 hours. There is a chance for LIFR
conditions at KFOE as ceilings may fall to 400 feet. Areas of light
fog may also reduce visiblities. The patchy freezing drizzle
chances are decreasing after 9Z. The terminals may briefly have
low-MVFR ceilings late Friday afternoon but may go below IFR after
00Z SAT.


&&

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Gargan






AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 347 AM EST FRI DEC 19 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM EST FRI DEC 19 2014

A FAIRLY QUIET PATTERN IN THE CENTRAL PART OF THE CONUS...AS THE
SOUTHERN STREAM JET IS SITUATED OVER THE SOUTHERN TIER OF STATES
AND THE SYSTEM THAT BROUGHT SNOW TO THE AREA THIS PAST
TUESDAY/WEDNESDAY IS NOW SPINNING OVER PRINCE EDWARD ISLAND. CLOSER
TO THIS AREA...AN UPPER RIDGE STRETCHES FROM WISCONSIN TO JAMES
BAY...WHILE A UPPER TROUGH IS LOCATED OVER SASKATCHEWAN AND THE
NORTHERN PLAINS. BENEATH THE UPPER RIDGE...1028MB HIGH PRESSURE IS
CENTERED OVER NORTHERN LAKE SUPERIOR WITH A RIDGE STRETCHING SOUTH
THROUGH THE MID MISSISSIPPI VALLEY. THERE IS PLENTY OF DRY AIR ALOFT
ON THE RAP ANALYSIS ASSOCIATED WITH THIS UPPER RIDGE...BUT THE
SUBSIDENCE HAS STRENGTHENED THE INVERSION OVER THE GREAT LAKES AND
UPPER MISSISSIPPI VALLEY REGIONS AND AIDED IN AREAS OF LOW CLOUDS.
THE LARGEST AREA OF LOW CLOUDS COVERS MUCH OF MINNESOTA AND WESTERN
WISCONSIN...WITH THE EASTERN EDGE STRETCHING FROM GRAND MARAIS
MINNESOTA THROUGH IRONWOOD MICHIGAN AND TOWARDS MADISON WISCONSIN.
BUT THERE IS A POCKET OF CLOUDS THAT DEVELOPED OVER SOUTH CENTRAL
LAKE SUPERIOR LATE THIS EVENING (AIDED BY MARGINAL DELTA-T VALUES
FOR LAKE CLOUDS) AND WITH THE LIGHT NORTHERLY FLOW...SHIFTED INTO
THE KEWEENAW AND NORTH CENTRAL U.P.  DEFINITELY HAVE TO GIVE SOME
CREDIT TO THE REGIONAL GEM...WHICH SUPERBLY PICKED UP ON THESE
CLOUDS WITH THE 00Z RUN YESTERDAY. THESE CLOUDS ALLOWED TEMPERATURES
TO QUICKLY RISE AROUND 10 DEGREES AND LOCATIONS UNDER THEM ARE IN
THE MID-UPPER TEENS. ELSEWHERE IN THE U.P. SKIES ARE CLEAR AND WITH
THE LIGHT WINDS...TEMPERATURES HAVE FALLEN INTO THE LOWER SINGLE
DIGITS ABOVE AND BELOW ZERO.

THE UPPER RIDGE AND SURFACE HIGH CURRENTLY OVER THE AREA WILL
SLOWLY SHIFT EAST-SOUTHEAST TODAY AND TONIGHT...ALLOWING THE AREA
TO COME UNDER GREATER INFLUENCE OF THE WEAK UPPER TROUGH. THE LOW
CLOUDS WILL BE THE PRIMARY CONCERN FOR THE FORECAST FOR TODAY. WITH
GENERALLY LIGHT WINDS AND A RELATIVELY LOW SUN ANGLE...GETTING A
HANDLE ON THE LOW CLOUDS OVER THE NORTH CENTRAL AND KEWEENAW IS
DIFFICULT. FOLLOWING 925MB WINDS IN THE MODELS...WOULD EXPECT THEM
TO TRY TO NOSE A LITTLE FARTHER INLAND OVER THE CENTRAL (AND EVEN
THE EASTERN) PART OF THE U.P. TODAY...WHILE THE DEVELOPING LIGHT
SOUTHERLY FLOW WOULD LIKELY PULL DRIER AIR BACK INTO THE KEWEENAW
AND PUSH THOSE CLOUDS NORTH. BUT THAT INCREASING SOUTHERLY FLOW
WILL ALSO PULL THE CLOUDS RIGHT NEAR IRONWOOD INTO THE REST OF
GOGEBIC AND ONTONAGON COUNTIES THROUGH THE DAY TODAY...EVENTUALLY
REACHING IRON/HOUGHTON COUNTIES THIS EVENING AS THE LIMITED MIXING
DECREASES AND THE STRATUS CAN REALLY EXPAND. THESE LOW CLOUDS
(ALONG WITH MID CLOUDS FROM THE WEAK UPPER TROUGH AXIS SHIFTING EAST
INTO MINNESOTA) WILL CONTINUE TO SPREAD ACROSS UPPER MICHIGAN FROM
SOUTHWEST TO NORTHEAST TONIGHT AS SOUTHWESTERLY FLOW GRADUALLY
DEVELOPS.

AS FOR TEMPERATURES...EVEN WITH THE COLD START THIS MORNING IN
SOME LOCATIONS...EXPECT ANOTHER DAY OF HIGHS A LITTLE BIT
ABOVE NORMAL (UPPER 20S TO LOWER 30S). THE LOWS TONIGHT WILL BE
TRICKY...AS THEY DEPEND ON THE LOCATIONS OF THE CLOUD COVER. WHERE
SKIES ARE CLEAR OVER THE CENTRAL AND EAST...WOULD EXPECT ANOTHER
QUICK DROP TO TEMPS IN THE EVENING AND NEARING 0 UNDER LIGHT WINDS.
BUT WHERE THERE ARE CLOUDS...TEMPS WILL STRUGGLE TO FALL INTO THE
MID TEENS. WILL KEEP LOWS UP THE HIGHEST OVER THE FAR WEST...WHERE
THE CLOUDS WILL MOST LIKELY BE LOCATED.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM EST FRI DEC 19 2014

MAIN FCST CONCERNS IN THE MEDIUM/EXTENDED RANGE INCLUDE POPS ON SUN
NGT INTO MON AS A WAA REGIME DEVELOPS IN THE UPR LKS BTWN HI PRES
MOVING INTO NEW ENGLAND AND LO PRES TAKING SHAPE IN THE NRN PLAINS
ASSOCIATED WITH A STRONGER SHRTWV RIDING OVER A RDG ALONG THE W
COAST. THE POTENTIAL FOR A HEAVIER SYNOPTIC THEN LK ENHANCED SN IS
STILL THERE FOR TUE THRU XMAS AS THE DIGGING SHRTWV DEEPENS AN UPR
TROF OVER THE CENTRAL CONUS AND A LO PRES SOMEWHERE IN THE GREAT
LKS. BUT THERE REMAINS SOME INCONSISTENCIES AMONG THE MEDIUM/LONG
RANGE GUIDANCE ON THIS LO AND HOW QUICKLY A SECOND LO WL TAKE
SHAPE...SO CONFIDENCE IS LO ON THE FCST FOR MON THRU XMAS.

SAT/SAT NGT...A SFC HI PRES RDG STRETCHING FM WRN QUEBEC INTO THE
MID MS RIVER VALLEY ON SAT MRNG WILL MOVE SLOWLY TO THE E AND TO
NEAR NEW ENGLAND TO THE OH RIVER VALLEY BY 12Z SUN UNDER LGT W FLOW
ALOFT. A WEAK SHRTWV EMBEDDED IN THIS W FLOW WL BE DRIFTING THRU THE
UPR LKS DURING THIS PERIOD. ALTHOUGH THERE WL BE SOME WAA IN THE SW
FLOW ON THE BACK SIDE OF THE DEPARTING HI AND PVA IN ADVANCE OF THE
SHRTWV...MODELS SHOW ONLY WEAK ISENTROPIC ASCENT/DEEP LYR QVECTOR
CNVGC/UVV IN THE ABSENCE OF SGNFT MSTR INFLOW. SINCE FCST SDNGS
INDICATE LIMITED DEEP SATURATION...WL MAINTAIN GOING DRY FCST AND
MOCLDY SKIES. TEMPS SHOULD RUN ABOVE NORMAL FOR THE SEASON WITH H85
TEMPS NOT FAR FM -5C TO -7C.

SUN/SUN NGT...MOST OF THE MEDIUM RANGE OPERATIONAL MODELS SHOW
ANOTHER MORE COMPACT SHRTWV CROSSING THE UPR LKS ON LATE SUN INTO
EARLY MON ACCOMPANIED BY SOME SHARPER DPVA. IN TANDEM WITH SOME MORE
IMPRESSIVE ISENTROPIC ASCENT IN THE SSW FLOW BTWN THE DEPARTING HI
PRES RDG TO THE E AND FALLING MSLP IN THE NRN PLAINS ASSOCIATED WITH
A STRONGER SHRTWV RIDING THRU THE NRN ROCKIES AND OVER THE UPR RDG
OFF THE W COAST...MODELS DO GENERATE SOME WIDESPREAD ALBEIT LGT PCPN
AT TIMES DURING THIS PERIOD. THE GFS SHOWS A WEAKER SHRTWV/DYNAMIC
FORCING...BUT ENUF ISENTROPIC ASCENT TO GENERATE SOME LGT PCPN AS
WELL. FCST WL SHOW A PERIOD OF UP TO HI CHC POPS TO REFLECT MODEL
DISCREPANCIES ON THE TIMING OF THE STRONGER UVV. SSW FLOW UP THE
LENGTH OF LK MI MAY SUPPORT SOME HIER POPS OVER THE E...BUT MARGINAL
CHILL OF THE AIRMASS FOR LK ENHANCEMENT AND SOME SHEAR SHOULD LIMIT
THE POTENTIAL FOR A SGNFT IMPACT. TEMPS WL REMAIN ABOVE NORMAL...
ESPECIALLY ON SUN NGT WITH CLD COVER AND A STEADY S WIND GREATLY
LIMITING THE DIURNAL TEMP FALL.

MON THRU XMAS DAY...ALTHOUGH THE MEDIUM/LONG RANGE GUIDANCE ARE IN
AGREEMENT AN UPR TROF WL DEEPEN WITH AN H5 LO CLOSING OFF SOMEWHERE
OVER THE CENTRAL CONUS DOWNSTREAM OF THE RDG OVER THE FAR W AND THAT
THE CLOSED LO/UPR TROF WL TAKE ON A NEGATIVE TILT BY LATE TUE/XMAS
EVE...THERE ARE CONSIDERABLE DIFFERENCES ON THE FCST MSLP AND
THERMAL FIELDS. THE 12Z AND 00Z GFS ENSEMBLE SPREAD ON THE FCST LO
POSITION ON TUE/WED WAS QUITE WIDE...REFLECTING THE RATHER POOR
PREDICTABILITY OF THIS PATTERN WITH THE MAIN PLAYERS STILL OUT OVER
THE DATA POOR PACIFIC OCEAN. IN GENERAL...THE GFS IS FARTHER N WITH
THE RESULTING SFC LO AND THUS SHOWS WARMER LLVL TEMPS THAT WOULD BE
SUFFICIENT FOR A GOOD DEAL OF THE PCPN TO FALL AS RA OVER A GOOD
PORTION OF THE CWA. THE 00Z ECWMF ON THE OTHER HAND SHOWS A FARTHER
S TRACK FOR THE SFC LO AND QUICKER REDEVELOPMENT OF A DEEPER SECOND
LO ASSOCIATED WITH THE SHARPLY DIGGING SHRTWV INTO THE TROF THAT ALL
THE MODELS EVENTUALLY LATCH ON TO AS THE MAIN FEATURE. THE 00Z UKMET
IS CLOSER TO THE ECMWF...WHILE THE CNDN IS MORE OF A COMPROMISE.
SINCE BOTH THE GFS/ECWMF HAVE SHOWN CONTINUITY FM PREVIOUS RUNS AND
THERE IS CONSIDERABLE DIFFERENCES...FOLLOWED A MODEL CONSENSUS APRCH
FOR FCST PREPARATION. DID INCREASE POPS ABOVE THE CONSENSUS ON WED/
THU NEAR LK SUP WITH CYC NE UPSLOPE FLOW SHIFTING TO THE NW BY XMAS
TO THE NW OF DEEPENING LO AND DRAWING COLDER AIR INTO THE UPR LKS
THAT WOULD BE SUFFICIENT FOR SOME LK ENHANCEMENT /H85 TEMPS NEAR
-10C ON XMAS/.
&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1227 AM EST FRI DEC 19 2014

MVFR CLOUDS WHICH DEVELOPED AT THE TAF SITES LAST EVENING WILL
CONTINUE TO BE A FCST CONCERN OVER THE TAF PD. KIWD IS ON THE
EASTERN EDGE OF A MASS OF LOW CLOUDS OVER MN AND MUCH OF WESTERN
WI...AND GIVEN THAT THE PREVAILING WIND FLOW WILL CONTINUE TO PUSH
THE CLOUD DECK INTO THE AREA DO NOT SEE MUCH IMPROVEMENT OVER THE
NEXT 24 HOURS. MVFR LAKE CLOUDS HAVE DEVELOPED AT KSAW AND THESE
CLOUDS LIKELY WILL PUSH INTO KCMX OVERNIGHT AS WELL UNDER LIGHT ERLY
FLOW. LOOK FOR THIS CLOUD DECK TO LIFT AT BOTH KCMX AND KSAW LATE
THIS MORNING AS LIGHT WINDS TURN SE OR TO AN OFFSHORE/DOWNSLOPE
DIRECTION.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 345 AM EST FRI DEC 19 2014

EXPECT LIGHT WINDS UNDER 20 KTS ASSOCIATED WITH HI PRES PASSING THRU
THE UPPER LAKES TODAY TO SHIFT TO THE S BUT REMAIN UNDER 20 KTS
UNTIL AT LEAST SUN. THE S WINDS MAY INCREASE UP TO 25 KTS OVER
MAINLY THE E HALF OF THE LAKE LATER SUN INTO MON IN ADVANCE OF AN
APPROACHING LO PRES. AS ANOTHER LO PRES DEVELOPS TO THE S...THE FLOW
WILL TEND TO BACK AND WEAKEN ON TUE. DEPENDING ON HOW QUICKLY THIS
SECOND LO DEVELOPS AND WHERE IT TRACKS...THERE COULD BE A NW GALE
EVENT ON WED OR XMAS DAY.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...SRF
LONG TERM...KC
AVIATION...VOSS
MARINE...KC




AREA FORECAST DISCUSSION

NWS DETROIT/PONTIAC MI

 1154 PM EST THU DEC 18 2014

.AVIATION...

//DISCUSSION...

WEAK SURFACE TROUGHING SUSTAINING A LIGHT MIX OF FREEZING DRIZZLE
WITH SOME SNOWFLAKES EARLY THIS MORNING. THIS PRECIPITATION IS
EXPECTED TO DIMINISH IN COVERAGE THROUGH THE EARLY MORNING HOURS.
THE EXISTING DEEP PLUME OF LOW LEVEL MOISTURE AND ASSOCIATED MVFR
CEILING WILL BE SLOWER TO DECREASE. UPSTREAM SATELLITE TRENDS
WOULD BRING THE EDGE OF THE CLEARING LINE NOW MOVING THROUGH
NORTHERN LOWER INTO MBS BY DAYBREAK. MOISTURE MAY BE SLOWER TO
ERODE TOWARD THE SOUTH AND WILL MAINTAIN A MORE GRADUAL CLEARING
INTO THE REMAINDER OF SE MICHIGAN ON FRIDAY. A LIGHT WIND FIELD
THROUGH THE PERIOD.

FOR DTW...THERE WILL CONTINUE TO BE THE POTENTIAL FOR A LIGHT
MIXTURE OF FREEZING DRIZZLE AND SNOW THROUGH 09-10Z.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE CEILINGS REMAIN BELOW 5000 FT THROUGH FRIDAY
  MORNING...LOW CONFIDENCE INTO THE AFTERNOON.

* HIGH CONFIDENCE THAT PRECIPITATION TYPE WILL BE A MIXTURE OF LIGHT
  FREEZING DRIZZLE AND SNOW EARLY THIS MORNING.

&&

.PREV DISCUSSION...ISSUED 746 PM EST THU DEC 18 2014

UPDATE...

RECENT RADAR SHOWING A DEFINITIVE UPTICK IN A DEFINED STRIPE OF
FREEZING DRIZZLE...PERHAPS ARGUABLY CLOSER TO FREEZING RAIN GIVEN
THE RETURNS...NOW SHIFTING THROUGH SOUTHERN LIVINGSTON/NORTHERN
WASHTENAW. THIS FEATURE REMAINS ANCHORED WITHIN A LINEAR AXIS OF
ENHANCED LOW LEVEL CONVERGENCE ACCOMPANYING THE PASSAGE OF A
SFC-850 MB TROUGH. 18Z NAM AND RECENT RAP GUIDANCE SUGGEST THIS
FEATURE WILL SLOWLY TRANSLATE SOUTHWARD OVER THE NEXT SEVERAL
HOURS...EFFECTIVELY SUSTAINING A FAVORABLE ENVIRONMENT FOR
MAINTENANCE OF THIS ONGOING LIGHT PRECIPITATION. POCKETS OF LIGHT
FREEZING DRIZZLE MIXED WITH SOME SNOWFLAKES WILL CONTINUE
ELSEWHERE SOUTH OF I-69 THROUGH ROUGHLY THE MIDNIGHT
WINDOW...THEREAFTER A LOSS OF MOISTURE DEPTH THROUGH THE BASE OF
THE INVERSION LAYER AS POST-TROUGH WINDS FLIP TO NORTHERLY SHOULD
BRING A NORTH TO SOUTH DIMINISHING TREND. THE GOING CONDITIONS IN
LIVINGSTON/WASHTENAW LIKELY CLOSING IN ON THE EDGE OF A VERY
SHORT FUSED ADVISORY HEADLINE. CALLS TO BOTH COUNTIES INDICATE
SLICK SPOTS ON SOME BRIDGES/OVERPASSES WITH ASSOCIATED SPINOUTS.
THIS BAND DOES APPEAR TRANSIENT ENOUGH AND OF SHORT ENOUGH
DURATION AT THIS TIME TO HOLD TIGHT IN HANDLING THE SITUATION
WITH SPECIAL WEATHER STATEMENTS /SPSDTX/...BUT WILL CONTINUE TO
MONITOR.

PREV DISCUSSION...ISSUED 355 PM EST THU DEC 18 2014

SHORT TERM...TONIGHT

FREEZING DRIZZLE AND LIGHT SNOW ACROSS SOUTHEAST MICHIGAN IS SLOWLY
BECOMING LESS WIDESPREAD AS THE AFTERNOON PROGRESSES. THE MAIN
CONCERN FOR TONIGHT WILL BE TIMING THE ENDING OF THE FREEZING
DRIZZLE AND WHETHER CLOUDS WILL STICK AROUND. WHILE CURRENT
SATELLITE IMAGERY IS SHOWING DRIER AIR SLOWLY PROGRESSING SOUTHWARD
OUT OF CANADA...PROGRESSION IS REALLY SLOW AND CURRENTLY NOT
ANTICIPATING THE DRY SURGE TO REACH SOUTHEAST MICHIGAN UNTIL CLOSER
TO DAYBREAK FRIDAY MORNING. WITH THE LOW LEVEL MOISTURE STICKING
AROUND OVERNIGHT...LOW LEVEL STRATUS IS EXPECTED TO REMAIN OVER THE
CWA. THE CLOUDS WILL KEEP TEMPERATURES FROM DROPPING TOO MUCH
OVERNIGHT AND HAVE THEREFORE OPTED TO SIDE ON THE WARMER SIDE OF
MODEL GUIDANCE FOR LOWS. EXPECT MID 20S ACROSS THE METRO DETROIT
AREA AND LOW TO MID 20S FOR THE REST OF THE CWA.

IN ADDITION...WHILE DRIZZLE IS DIMINISHING THE FORECASTED STRATUS
COULD RE-INITIATE DRIZZLE FOR THE EARLY PART OF THE EVENING. CURRENT
MODEL SOUNDINGS SHOW A WELL SATURATED BOUNDARY LAYER WITH LIGHT
WINDS OVER SOUTHEAST MICHIGAN THROUGH MOST OF THURSDAY EVENING WHICH
COULD HELP IN THE RE-DEVELOPMENT OF LIGHT DRIZZLE. AS TEMPERATURES
FALL BELOW FREEZING AFTER SUNSET...THE DRIZZLE COULD BECOME FREEZING
DRIZZLE AND MIX WITH SNOW ONCE AGAIN. HOWEVER...CONFIDENCE IN THIS
OCCURRING IS LOW AT THIS FORECAST ISSUANCE AND HAVE ONLY INCLUDED
FREEZING DRIZZLE IN THE FORECAST THROUGH 00Z /7PM/ THURSDAY. WILL
HAVE TO MONITOR OVER THE NEXT SEVERAL HOURS TO SEE IF DRIZZLE STARTS
TO DEVELOP.

LONG TERM...FRIDAY THROUGH WEDNESDAY

THE UPPER LEVEL PATTERN OVER THE UPPER MIDWEST AND GREAT LAKES
STATES WILL DEAMPLIFY TO THE POINT THAT PSEUDO ZONAL FLOW WILL BE
THE PRIMARY SETUP THROUGH MUCH OF THE UPCOMING WEEKEND. THE MAIN
WESTERLY JET AXIS WILL RESIDE OVER THE SOUTHEASTERN UNITED STATES
WITH VERY NOISY SHORTWAVE ENERGY PASSING WITHIN A FADING MIDLEVEL
COL STRUCTURE. HIGH COLUMN STABILITY SEEMS TO BE THE PRIMARY DRIVER
OF A SURFACE ANTICYCLONE THAT WILL PASS DIRECTLY THROUGH
SOUTHEASTERN MICHIGAN. DEAMPLIFIED FLOW WEAK SHORTWAVE ENERGY AND
RESULTS IN VERY QUIET WEATHER THAT MAINTAINS A STATUS QUO FROM A
TEMPERATURE AND PRECIPITATION PERSPECTIVE.

THERE WILL STILL BE SOME FORECAST DIFFICULTY IN THE EXPECTED
PATTERN...PRIMARILY THAT OF CLOUDS AND CLOUD TRENDS. MODEL DATA IS
VERY AGGRESSIVE WITH A SOUTHWARD PUSH OF DRY AIR LATE
TONIGHT...MAKING INROADS OVER MANY AREAS PRIOR TO SUNRISE. PATTERN
RECOGNITION AND OBSERVATIONAL DATA SUGGESTS OTHERWISE...THE HEAVY
LOOK OF SHEARING OCCURRING ALONG A MIDLEVEL CONVERGENCE BOUNDARY
THAT IS SUPPORTING THE SURFACE TROUGH AND CONTINUATION OF
REFLECTIVITY FINELINE. THE PROBLEM WITH THIS SURFACE TROUGH IS
THAT IT CONTINUES TO HOLD ON STRONGER THAN ANY OF THE MODEL
SOLUTIONS HAVE BEEN SUPPORTING. RH AND SPECIFIC HUMIDITY ANALYSES
SUGGESTS THAT CLEARING MAY BE DOWN TO THE M59 CORRIDOR BY SUNRISE
WITH CLOUDS SOLIDLY LOCKED IN OVER THE CENTRAL DETROIT METRO AREA
SOUTHWARD. THE CLEARING TREND MAY THEN ACCELERATE FOR THESE
SOUTHERN LOCATIONS AS WE HEAD INTO FRIDAY EVENING. FINALLY...COULD
BE LOOKING AT A PERIOD OF CLEAR SKIES FRIDAY NIGHT AND INTO THE
FIRST PART OF SATURDAY. LONGWAVE HEIGHT REBOUND AND WIND DIRECTION
CHANGE TO THE SOUTH BY LATE SATURDAY SUPPORTS THE RETURN OF
ORGANIZED MOISTURE ADVECTION AND CLOUDS.

ACTIVE WEATHER IS EXPECTED FOR THE REMAINDER OF THE FORECAST. THIS
WILL OCCUR AS A STRONG PACIFIC JET ENTERS THE PACIFIC
NORTHWEST...DEEPENS THE LONGWAVE TROUGH OVER THE CENTRAL CONUS...AND
EVENTUALLY CAUSES THE TROUGH TO BECOME NEGATIVELY TILTED AS THE JET
ENERGY ROUNDS THE BASE OF THE TROUGH TOWARD CHRISTMAS EVE. AT THE
SURFACE...A WEAKER LOW PRESSURE SYSTEM WILL EVOLVE OVER THE NORTHERN
PLAINS MONDAY/TUESDAY...EVENTUALLY GETTING ABSORBED BY A POTENTIALLY
STRONGER STORM LIFTING NORTHWARD FROM THE DEEP SOUTH. STILL LOTS OF
POSSIBLE SOLUTIONS AS TO HOW/WHERE THIS INTERACTION TAKES PLACE SO
THE DETAILS ARE FAR FROM BEING CLEAR. AT THIS POINT WILL HIGHLIGHT
THE POTENTIAL FOR IMPACTFUL WEATHER CENTERED AROUND
TUESDAY/WEDNESDAY. IMPACTS IN TERMS OF PRECIPITATION WILL BE MOST
LIKELY DURING THE MONDAY NIGHT THROUGH WEDNESDAY TIME FRAME.
MODEL CONSENSUS...WEAK AS IT IS AT THIS POINT...SUGGESTS WE HAVE A
BETTER CHANCE OF BEING ON THE WARMER SIDE OF THIS SYSTEM MONDAY
NIGHT THROUGH TUESDAY NIGHT...WITH COLDER AIR AND BREEZY CONDITIONS
BY CHRISTMAS EVE.

MARINE...

HIGH PRESSURE WILL BUILD INTO THE AREA TONIGHT...MAINTAINING
RELATIVELY RELAXED NORTHERLY WINDS FOR THE TIME OF YEAR. THE SURFACE
HIGH IS FORECASTED TO DRIFT ACROSS THE CENTRAL GREAT LAKES THIS
WEEKEND WITH SOUTHERLY FLOW EVENTUALLY RETURNING ON SUNDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

AVIATION.....MR
UPDATE.......MR
SHORT TERM...RK
LONG TERM....CB/DT
MARINE.......CB


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).



AREA FORECAST DISCUSSION

NWS ST LOUIS MO

 300 AM CST Fri Dec 19 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 300 AM CST Fri Dec 19 2014

A weak ridge of high pressure which extends from the Great Lakes
region south through the Mid-Mississippi Valley is in control of our
weather today.  Soundings are showing plenty of low level moisture
trapped under an inversion at around 850mb.  The vertical structure
of the atmosphere is much like what we had last weekend with the
moisture stratified in the low levels, so I don`t expect much
sunshine for the majority of the area...with the possible exception
of south central and extreme southwest Illinois.  Some drier air is
trying to drift in on weak easterly low level flow.  Vertical cross
sections show intermittent weak upward motion through the day,
primarily over central Missouri, and short term guidance spits out a
hundredth of QPF here and there.  Additionally, the HRRR shows some
weak simulated radar echos over parts of central and southeast
Missouri today, so have added in a little patchy drizzle to the
forecast.

Carney

.LONG TERM:  (Tonight through Thursday)
Issued at 300 AM CST Fri Dec 19 2014

(Tonight - Saturday)

The brunt of a storm system is expected to pass relatively unnoticed
to our south this evening, and if it weren`t for some interaction
with a more northerly component, would probably result in no
precipitation anywhere, but such as it is, some very light snow
looks to be possible early this evening for an area primarily south
of STL metro.  This arrangement should be short-lived, with much of
the mid and upper level moisture quickly being shunted off to the
east, leaving behind extensive low cloud cover.  At this point,
there is good model consensus on a weak WAA, convergence regime
setting up at the low levels that noses into central MO by midnight
tonight and then snaking its way northward towards the UIN area by
Saturday morning.  Have added in patchy drizzle as a result.  For
now, expecting influence of the surface RIDGE to trump this for STL
metro and areas S and E.  Temps will probably not go very far
tonight with clouds hanging tough, although where the surface RIDGE
is dominant, should see a steady but slow drop...but for areas to
the N and W of STL metro where a light S flow will persist, near
steady temps are expected.  Speaking of temps, especially to the N
and W of STL metro where drizzle is expected to develop, readings
will be within a degree or two of the freezing mark and so this will
probably manifest more as patchy FZDZ for areas in northeast MO and
west-central IL.  Prefer the lower MOS temps for Saturday maxes
given cloud cover expected, but they should still rebound into the
upper 30s and low 40s.

(Sunday - Wednesday)

A rather deep upper level TROF is expected to develop later on
Sunday over the central CONUS and then take a good part of the week
before finally shifting east.  Maintained the highest PoPs for
Monday thru Tuesday, where there is good model consensus on when the
TROF will be close enough, yet its axis still just upstream...and
then reduce to slight chances by Wednesday when the TROF axis by
this time will have shifted to the east.

While much of the precipitation will be just rain, especially on the
front-end, enough cold air starts working in on Tuesday, especially
aloft, that will allow the atmosphere to sustain a changeover to
snow.  The only limiting factor at this point will be surface and/or
boundary layer temps that will ultimately determine the rain vs.
snow question.  GFS and EC MOS surface temps suggest this will not
happen for most locales until late in the day on Tuesday with snow
then expected as the dominant p-type from that point on.  This will
also be when the upper TROF axis will be crossing thru, and so what
is left will probably not be much, but perhaps light snow accums
will be possible Tuesday night and early Wednesday.  This will be
our only realistic chance at a white Christmas, and something to
watch, as a deeper system that digs a bit more south would up the
potential.

(Christmas)

Models have been advertising for several days now a transitional
period this day which should give us a net result of quiet wx with
near seasonal temps.  Nothing has changed with the current model
runs so will let it stand.

TES

&&

.AVIATION:  (For the 06z TAFs through 06z Friday Night)
Issued at 1142 PM CST Thu Dec 18 2014

Extensive area of IFR conditions currently cover most of central
Missouri reach to just west of the St. Louis metro area and just
southwest of KUIN.  Expect KCOU to remain IFR until mid afternoon
on Friday. Expect that ceilings and visibilities will slowly fall
at KUIN and the St. Louis metro TAF sites the remainder of the
night, and then slowly improve back to MVFR by late morning or
early afternoon on Friday. Winds will remain light through the
period.

Specifics for KSTL:  Expect current ceilings to fall below 2000 ft
in the next hour or two as large area of IFR conditions just west
of the terminal moves east. Then ceilings and visibilities will
likely slowly decrease through the night given the high atmospheric
moisture and light winds. LIFR conditions are still expected
between 10-17Z. Do expect some slow improvement in ceilings and
visibilities during the afternoon hours, with ceilings increasing
above 2000 feet after 22Z.

Britt

&&

.PRELIMINARY POINT TEMPS/POPS:
Saint Louis     35  31  41  34 /  10  10  10   5
Quincy          32  29  38  31 /  10  10  10  10
Columbia        35  33  41  34 /  10  10  10   5
Jefferson City  37  34  42  34 /  10  10  10   5
Salem           35  29  41  31 /  10  10   5   0
Farmington      36  30  43  31 /  10  10  10   0

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX





AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

 328 AM CST FRI DEC 19 2014

.SYNOPSIS...
ISSUED AT 328 AM CST FRI DEC 19 2014

A SURFACE RIDGE OF HIGH PRESSURE EXTENDS ACROSS THE GREAT LAKES REGION.
A SUBSTANTIAL AREA OF STRATUS EXTENDS ALONG THE WESTERN PERIPHERY OF
THE SURFACE HIGH ACROSS THE EASTERN DAKOTAS...THE EASTERN HALF OF
NEBRASKA AND MOST OF KANSAS. ON THE WESTERN EDGE OF THE
STRATUS...LOCALLY DENSE FOG TO A QUARTER MILE CONTINUES FROM NEAR
HAYES CENTER THROUGH NORTH PLATTE...BROKEN BOW AND BASSETT. FURTHER
EAST WITHIN THE STRATUS...PATCHY FOG WITH CURRENT VSBYS FROM 2-5SM.
TEMPERATURES IN WESTERN NEBRASKA RANGING FROM 29 AT ONL TO 12 AT
VTN.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 328 AM CST FRI DEC 19 2014

LOCALLY DENSE FOG ALONG THE WESTERN EDGE OF STRATUS WITH PATCHY FOG
FURTHER EAST TO PERSIST THROUGH MID MORNING ACROSS THE SOUTHEASTERN
ZONES. ONCE FOG BURNS OFF...STRATUS WILL SLOWLY CLEAR EAST OF A
BROKEN BOW THROUGH ONEILL LINE THIS AFTERNOON. TO THE WEST...MOSTLY
SUNNY SKIES. WITH SLIGHTLY WARMER H85 TEMPS TO NEAR 3C FROM VTN
SOUTHWEST THROUGH OGA AND IML SUPPORT HIGHS IN THE UPPER 30S TO NEAR
40. WITH LIGHT WINDS REMAINING SOUTH AND STRATUS LINGERING INTO THE
AFTERNOON AT ONL AND BARTLETT...HIGHS LIMITED TO THE LOWER 30S.
CURRENT FORECAST TO BE NEAR...BUT SLIGHTLY COOLER THAN MAV GUIDANCE
ALL AREAS DUE TO EXISTING SNOW COVER EFFECTS.

FOR TONIGHT...STRATUS SHOULD REMAIN JUST EAST OF THE FAR EASTERN
ZONES. EXPECTING AN INCREASING IN SOME MID AND HIGH CLOUDINESS AS AN
UPSTREAM DISTURBANCE TRACKS ACROSS MONTANA AND WYOMING. SUBSTANTIAL
ONSHORE MOISTURE WILL STREAM INTO THE PACIFIC NORTHWEST WITH
APPROACH OF A STRONGER DISTURBANCE. LOWS TO FALL  INTO THE MID
TEENS...WITH COLDER LOWS NEAR 10 ABOVE EASTERN PANHANDLE INTO THE
PLATTE RIVER VALLEY.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 328 AM CST FRI DEC 19 2014

12Z SATURDAY AND BEYOND. WEAK SURFACE TROUGH WILL RESIDE EAST OF
THE FORECAST AREA ON SATURDAY...PROVIDING FOR LIGHT WESTERLY
DOWNSLOPING FLOW OFF THE HIGH PLAINS. THIS WILL ALLOW FOR PARTIAL
CLEARING AND A WEAK PUSH OF WARM AIR ADVECTION OFF THE HIGHER
TERRAIN. H85 TEMPERATURES WARM SEVERAL DEGREES ABOVE 0C...WHICH
WILL PROVIDE FOR SFC HIGHS IN THE LOWER 40S...WITH SOME UPPER 30S
ACROSS THE FAR NORTHEAST WHERE FOG AND/OR STRATUS REMAINS IN THE
FORECAST SATURDAY MORNING. LATE SATURDAY AFTERNOON AND EVENING A
WEAK WAVE WILL DROP SOUTHEAST FROM THE NORTHERN ROCKIES ONTO THE
NORTHERN PLAINS. THIS WILL FORCE A WEAK BOUNDARY THROUGH WESTERN
NEBRASKA...EFFECTIVELY KEEPING THE BL SOMEWHAT MIXED. THE RESULT
WILL BE SLIGHTLY WARMER OVERNIGHT LOWS...WITH TEENS ANTICIPATED
WHERE THE ATMOSPHERE CAN FULLY DECOUPLE /RIVER VALLEYS/...BUT
LOWER 20S ELSEWHERE. SUNDAY...TEMPERATURES WARM ONCE AGAIN AS A
LEE TROUGH DEEPENS AND ALLOWS FOR A RETURN TO A SOUTHWESTERLY
TRAJECTORY OF THE LOWER TROPOSPHERIC FLOW. H85 TEMPS WARM TO NEAR
5C ACROSS MUCH OF THE SANDHILLS...THIS SHOULD TRANSLATE TO MID TO
UPPER 40S OVER MUCH OF THE REGION SUNDAY AFTERNOON. SUNDAY EVENING
THROUGH MONDAY...ALL AVAILABLE GUIDANCE INDICATES A SHORTWAVE
DIVING SOUTH ACROSS THE PLAINS. SUFFICIENT LIFT AND MOISTURE IS
SHOWN FOR PRECIPITATION WITHIN THE REGION...BUT SUBTLE DIFFERENCES
IN THE WAY THE LONGER RANGE MODELS HANDLE THE UPPER JET STRUCTURE
CREATES UNCERTAINTY IN THE FORECAST. THE GFS CONTINUES TO BE
SLIGHTLY EAST WITH THE STRONGER JET SUPPORT...WHILE THE ECMWF IS
SLIGHTLY WEST. THUS THERES A DISAGREEMENT ON WHERE THE STRONGEST
MID LEVEL FRONTOGENETIC FORCING WILL RESIDE...THE GFS FAVORS THE
EASTERN PANHANDLE SOUTHEAST THROUGH LINCOLN AND CUSTER
COUNTIES...THE EURO IS WEST OVER THE HIGHER TERRAIN OF
COLORADO/WYOMING. FOR THIS...DIDN/T GET TOO CARRIED AWAY ON POPS
JUST YET...MAINTAINING A SLIGHT CHANCE/LOW END CHANCE WORDING. IF
PRECIP OCCURS THERMO PROFILES INITIALLY FAVOR ALL RAIN ACROSS THE
FORECAST AREA SUNDAY EVENING...BUT ENOUGH UNCERTAINTY REMAINS
OVERNIGHT TO KEEP A MENTION OF RAIN OR SNOW GOING...ESPECIALLY
GOING INTO MONDAY AS THE GFS INDICATES A GOOD PUSH OF SUB 0C H85
AIR ACROSS THE FORECAST AREA...THE EC IS SLOWER TO ARRIVE WITH THE
COLD AIR. LIGHT QPF MAY CONTINUE INTO TUESDAY ACROSS OUR EAST AS
THE UPPER FLOW TURNS NORTHERLY AND ADDITIONAL UL ENERGY DIVE SOUTH
ACROSS THE PLAINS. TEMPERATURE PROFILES WOULD BE SUPPORTIVE OF ALL
SNOW AT THIS POINT.

THERE REMAINS A STRONG SIGNAL THAT A ROBUST UPPER LEVEL TROUGH WILL
DROP SOUTH INTO THE PACIFIC NORTHWEST MID-WEEK THEN PROCEED TOWARD
THE GREAT BASIN AND EVENTUALLY EMERGE ON THE PLAINS. THE MODELS ARE
ALSO SUGGESTING INCREASED FRONTOGENESIS ALONG/BEHIND A STRONG ARCTIC
FRONT POISED TO ARRIVE ATOP THE SANDHILLS ON CHRISTMAS.  THE MODELS
CONTINUE TO WAFFLE A BIT ON THE PROJECTED SYSTEM...BUT CONFIDENCE IS
SLOWLY INCREASING IN A POTENTIAL WINTER STORM FOR CHRISTMAS AND LATE
WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1122 PM CST THU DEC 18 2014

LIFR IS EXPECTED THROUGH AT LEAST 10Z AT KLBF. THE MODELS SHOW A
SLUG OF DRY AIR ALOFT MOVING THROUGH THIS AREA. THE RAP AND HRRR
SHOW THE FOG EXITING KLBF AROUND 15Z. THE NAM IS A BIT QUICKER.
THIS CONDITIONS WILL BE FAVORABLE FOR LIFR THROUGH 10Z BUT FLIGHT
CONDITIONS MAY IMPROVE 10Z-14Z...SOONER THAN FORECAST.

VFR IS EXPECTED ELSEWHERE OVERNIGHT AND FRIDAY EXCEPT ALONG AND
EAST OF A LINE FROM KANW-KLBF WHERE MVFR/LOCAL LIFR WILL CONTINUE
THROUGH 21Z. THIS AREA OF LOW CLOUDS AND FOG SHIFTS SLOWLY EAST
FRIDAY.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...JACOBS
AVIATION...CDC









AREA FORECAST DISCUSSION...UPDATED

NWS NORTH PLATTE NE

 1122 PM CST THU DEC 18 2014

.SYNOPSIS...
ISSUED AT 307 PM CST THU DEC 18 2014

H5 ANALYSIS FROM THIS MORNING REMAINED ACTIVE ACROSS THE
LOWER 48 STATES. A CLOSED LOW WAS PRESENT ALONG THE MAINE ATLANTIC
COAST. FURTHER WEST...A SHORTWAVE WAS NOTED OVER CENTRAL SOUTH
DAKOTA...WITH A SECOND SHORTWAVE OVER CENTRAL KS AND A THIRD SHORTWAVE
OVER SWRN AZ. HT FALLS OF 50 TO 80 METERS...IN ASSOCIATION WITH THE
DISTURBANCE IN KANSAS...WERE NOTED OVER MISSOURI AND NRN OK. SOUTH
OF THE KANSAS DISTURBANCE...A 50 TO 70 KT JET STREAK EXTENDED FROM
SERN NM INTO THE MID ATLANTIC AND CANADIAN MARITIMES. AT THE
SURFACE...FOG AND STRATUS DOMINATED CENTRAL AND EASTERN PORTIONS OF
THE FORECAST AREA TDY WITH SOME CLEARING NOTED IN THE EASTERN
NEBRASKA PANHANDLE...AS WELL AS THE WESTERN SANDHILLS AND FAR SWRN
NEBRASKA. TEMPERATURES AS OF 3 PM CST RANGED FROM 27 AT AINSWORTH
AND VALENTINE TO 30 AT THEDFORD.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 307 PM CST THU DEC 18 2014

THE MAIN FORECAST CONCERNS OVER THE SHORT TERM ARE THE TEMPERATURES
AND THE POTENTIAL FOR FOG FORMATION.

IN ASSOCIATION WITH THE MOIST RETURN FLOW FROM THE SURFACE HIGH
PRESSURE SITUATED OVER THE UPPER MIDWEST...LOW STRATUS WILL CONTINUE
MOVING SLOWLY EASTWARD THIS EVENING AND TONIGHT ACROSS THE FORECAST
AREA. RELATIVELY DRIER AIR ASSOCIATED WITH A WEST WIND MOVES INTO THE
PANHANDLE AND FAR WESTERN COUNTIES TONIGHT...KEEPING THE SKY
RELATIVELY CLOUD FREE. THE 18/12Z MODEL RUNS...ESPECIALLY THE NAM
AND RAP...AND CURRENT TRENDS IN THE VISIBLE SATELLITE IMAGES BRING
THE BACK EDGE OF THE STRATUS TO THE HIGHWAY 83 CORRIDOR BY 19/00Z.
LIGHT WINDS AND A CLEARING SKY WILL ALLOW THE ATMOSPHERE TO DECOUPLE
OVERNIGHT...AND WITH DEW POINT DEPRESSIONS GENERALLY THREE DEGREES
OR LESS...FOG FORMATION IS FAVORABLE ALONG THE EDGE OF THE STRATUS
DECK. MIN TEMPS HAVE BEEN ADJUSTED DOWNWARD FROM THE PREVIOUS
FORECAST WEST OF HIGHWAY 83 TO ACCOUNT FOR THE DECOUPLING AND AN
EXISTING SNOW PACK IN MANY LOCATIONS. OVER NORTH CENTRAL NEBRASKA...WHERE
STRATUS IS EXPECTED TO REMAIN THROUGH THE NIGHT...HAVE KEPT MIN
TEMPS A FEW DEGREES WARMER.

FRIDAY...ANY FOG SHOULD BURN OFF BY 19/15Z AND MAX TEMPS WILL REFLECT
THE AMOUNT OF CLOUD COVER. DESPITE MOSTLY CLEAR SKIES AND WEST WINDS
FOR THE WESTERN 2/3 OF THE FORECAST AREA...HIGHS WILL STILL BE IN
THE UPPER 30S TO LOWER 40S AS 850HPA TEMPS STRUGGLE TO REACH 5C.
MODELS ARE CONSISTENT WITH KEEPING THE STRATUS FARTHER EAST...AND
HIGHS WILL STAY IN THE LOWER TO MID 30S. NOT LOOKING AT A DRIZZLE
THREAT AS FORECAST SOUNDINGS INDICATE RELATIVELY DRIER AIR RIGHT AT
THE SURFACE...TOO THIN OF A MOISTURE BAND...AND NO LIFT IN THE
NEAR SURFACE CLOUD LAYER.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 307 PM CST THU DEC 18 2014

MID RANGE...FRIDAY NIGHT THROUGH SUNDAY...IN THE MID
RANGE PERIODS...THE MAIN FORECAST CHALLENGE IS TEMPERATURES. FOR
FRIDAY NIGHT...BOTH THE LATEST NAM AND GFS SOLNS POSITION THE
WESTERN EDGE OF THE STRATUS DECK FROM SARGENT UP TO NAPER AT 00Z
SATURDAY. BY 12Z SATURDAY...THIS LINE EXTENDS ROUGHLY ALONG THE FAR
NERN BORDER OF THE FORECAST AREA. AS HAS BEEN THE CASE OVER THE PAST
COUPLE OF NIGHTS...THE WESTERN FRINGES OF THE STRATUS DECK IS WHERE
FOG WAS MOST PREVALENT. WITH LIGHT WINDS EXPECTED FRIDAY
NIGHT...DECIDED TO INSERT SOME PATCHY FOG ACROSS OUR FAR
NORTHEASTERN 4 COUNTIES. ELSEWHERE...CLEAR SKIES AND COLD TEMPS ARE
EXPECTED. WITH THE LIGHT WEST NORTHWESTERLY WINDS FORECAST ACROSS
SWRN NEBRASKA...DECIDED TO GO WITH SLIGHTLY COLDER LOWS IN THE
PLATTE RIVER VALLEY. ON SATURDAY...A WEAK SURFACE TROUGH WILL PUSH
EAST INTO THE CENTRAL SANDHILLS AND NORTH CENTRAL NEBRASKA. WITH
MOSTLY CLEAR SKIES...LIGHT WESTERLY WINDS AND H85 TEMPS IN THE LOW
SINGLE DIGITS ABOVE ZERO...HIGHS WILL REACH THE LOWER 40S...WITH
SOME MID AND UPPER 30S IN THE FAR NORTHEAST...WHERE STRATUS AND FOG
WILL BE POSSIBLE SATURDAY MORNING. FOR SATURDAY NIGHT AND
SUNDAY...LIGHT WESTERLY WINDS AND MOSTLY CLEAR SKIES ARE EXPECTED.
WITH THE EXCEPTION OF THE VALLEYS...WESTERLY WINDS SHOULD KEEP THE
BL SOMEWHAT MIXED SAT NIGHT. THIS WILL RESULT IN LOWS IN THE LOWER
20S WITH SOME TEENS POSSIBLE IN THE PLATTE VALLEY. SUNDAY WILL BE
THE WARMEST DAY OF THE PERIOD. WESTERLY WINDS WILL INCREASE AHEAD OF
AN APPROACHING COLD FRONT. SOUTH OF THE FRONT...H85 TEMPS WILL
INCREASE TO 3 TO 7C SUNDAY AFTERNOON...EQUATING TO HIGHS IN THE 40S
AND LOWER 50S. DECIDED TO UNDER CUT THIS A TAD BASED ON EXPECTED
RESIDUAL SNOW COVER AND THE THREAT FOR MID AND HIGH LEVEL CLOUDINESS
AS INDICATED IN THE GFS AND NAM H700-H500 RH PROGS.

SUNDAY NIGHT THROUGH CHRISTMAS DAY...FOR THE EXTENDED
PERIODS...PRECIPITATION CHANCES MONDAY-MONDAY NIGHT...FOLLOWED BY
PRECIPITATION CHANCES CHRISTMAS EVE NIGHT AND CHRISTMAS DAY WILL
HIGHLIGHT THE EXTENDED PERIODS. FOR MONDAY-MONDAY NIGHT...AN UPPER
LEVEL TROUGH OF LOW PRESSURE WILL DROP SOUTH FROM THE EASTERN
DAKOTAS INTO THE UPPER MIDWEST. AT THE SAME TIME ANOTHER...SEPARATE
UPPER LEVEL DISTURBANCE WILL DROP SOUTH ACROSS THE NORTHERN AND
CENTRAL ROCKIES. WITH BOTH THE GFS AND ECMWF SOLNS...SUFFICIENT LIFT
AND MOISTURE EXISTS WITH BOTH SYSTEMS TO PRODUCE PRECIPITATION.
ATTM...FEEL MORE CONFIDENT IN PRECIP CHANCES IN NORTHERN AND
NORTHEASTERN NEBRASKA IN ASSOCIATION WITH THE FIRST DISTURBANCE
MENTIONED ABOVE. ATTM THERE ARE SOME SUBTLE DIFFERENCES WITH THE
UPPER LEVEL JET STRUCTURE WITH THE WESTERN DISTURBANCE. THE ECMWF IS SLIGHTLY
FURTHER WEST WITH THE JET COMPARED TO THE GFS SOLN MONDAY...WHICH
FAVORS PRECIPITATION OVER THE ROCKIES VS. THE NEBR PANHANDLE AND FAR
SWRN CWA. ON TUESDAY AND THE FIRST HALF OF WEDNESDAY...THE FORECAST
AREA WILL BE BETWEEN SYSTEMS WITH MAINLY DRY CONDS EXPECTED. BY
MIDWEEK...A STRONG UPPER LEVEL TROUGH WILL DROP SOUTH INTO
IDAHO...UTAH AND NEVADA. THIS FEATURE WILL MIGRATE TO THE EAST
SOUTHEAST ON CHRISTMAS DAY. INCREASED MID LEVEL FRONTOGENESIS WILL
DEVELOP BEHIND AN EXITING ARCTIC FRONT CHRISTMAS DAY...WHICH WILL
LEAD TO INCREASED CHANCES FOR SNOW ACROSS THE FORECAST AREA. WITH
GOOD MODEL AGREEMENT NEXT WEEK...CONFIDENCE CONTINUES TO INCREASE IN
PRECIP CHANCES FOR CHRISTMAS DAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1122 PM CST THU DEC 18 2014

LIFR IS EXPECTED THROUGH AT LEAST 10Z AT KLBF. THE MODELS SHOW A
SLUG OF DRY AIR ALOFT MOVING THROUGH THIS AREA. THE RAP AND HRRR
SHOW THE FOG EXITING KLBF AROUND 15Z. THE NAM IS A BIT QUICKER.
THIS CONDITIONS WILL BE FAVORABLE FOR LIFR THROUGH 10Z BUT FLIGHT
CONDITIONS MAY IMPROVE 10Z-14Z...SOONER THAN FORECAST.

VFR IS EXPECTED ELSEWHERE OVERNIGHT AND FRIDAY EXCEPT ALONG AND
EAST OF A LINE FROM KANW-KLBF WHERE MVFR/LOCAL LIFR WILL CONTINUE
THROUGH 21Z. THIS AREA OF LOW CLOUDS AND FOG SHIFTS SLOWLY EAST
FRIDAY.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CLB
SHORT TERM...DS
LONG TERM...CLB
AVIATION...CDC






AREA FORECAST DISCUSSION

NWS BURLINGTON VT

 1252 AM EST FRI DEC 19 2014

.SYNOPSIS...
BROAD CYCLONIC CIRCULATION SURROUNDING SLOW-MOVING LOW PRESSURE
OVER THE CANADIAN MARITIMES WILL MAINTAIN CLOUDY SKIES AND A FEW
MOUNTAIN SNOW SHOWERS TONIGHT. HIGH PRESSURE BUILDS ACROSS THE
NORTH COUNTRY FRIDAY AND THROUGH THE WEEKEND...BRINGING GENERALLY
DRY WEATHER CONDITIONS...THOUGH SKIES WILL REMAIN VARIABLY CLOUDY
OWING TO LOW STRATUS. THE NEXT SIGNIFICANT STORM SYSTEM ARRIVES
FOR CHRISTMAS EVE WITH VERY WINDY AND MILD CONDITIONS...WITH
PERIODS OF MODERATE TO BRIEFLY HEAVY RAIN. BRISK AND SOMEWHAT
COLDER CONDITIONS ARE EXPECTED FOR CHRISTMAS DAY...WITH A
TRANSITION TO SNOW SHOWERS POSSIBLE...ESPECIALLY OVER THE HIGHER
TERRAIN.

&&

.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 1221 AM EST FRIDAY...NO SIGNIFICANT ADJUSTMENTS FOR 1230
UPDATE. PATCHY -FZDZ HAS MATERIALIZED ACROSS PORTIONS OF NRN NY
AND CENTRAL/NRN VT OVER THE PAST 3 HOURS AS PRIMARY DENDRITIC SNOW
GROWTH LAYERS ARE TRENDING UNSATURATED. THIS HAS BEEN PICKED UP
QUITE WELL ON THIS EVENING`S RAP SOUNDING PROFILES AND HAVE ISSUED
SPECIAL WEATHER STATEMENTS TO HIGHLIGHT POTENTIAL LIGHT GLAZE
ICING ON UNTREATED/ELEVATED SURFACES OVERNIGHT. OTHERWISE FORECAST
REMAINS IN GOOD SHAPE AS BLOCKED MOIST NORTHWESTERLY FLOW
CONTINUES ACROSS THE AREA. OTHER THAN THE PATCHY -FZDZ AND SOME
PASSING FLURRIES/LIGHT SHSN ACTIVITY OVERNIGHT...A GENERALLY
CLOUDY NIGHT IS EXPECTED AS TEMPERATURES SETTLE INTO THE LOWER AND
MID 20S BY SUNRISE FRIDAY. HAVE A GREAT NIGHT.

&&

.SHORT TERM /7 AM THIS MORNING THROUGH SATURDAY NIGHT/...
AS OF 230 PM EST THURSDAY...RELATIVELY TRANQUIL SHORT-TERM
PERIOD...ONLY ISSUE WILL BE EXTENT OF STRATUS AND ASSOCIATED
IMPACT ON RADIATIVE HEATING/COOLING AND TEMPERATURES. HIGH
PRESSURE CENTERED ACROSS THE GREAT LAKES FRIDAY DRIFTS ACROSS THE
NERN CONUS AND SERN CANADA SATURDAY AND SATURDAY NIGHT. THIS WILL
BRING LIGHT WINDS...ESPECIALLY ON SATURDAY. 12Z NAM HAS TRENDED
TOWARD HIGHER LOW-LEVEL RH FOR FRIDAY. WITH WEAK WIND FIELDS AND
LOW-LEVEL INVERSION LAYER/LOW SUN ANGLE...WILL KEEP ANY PARTIAL
CLEARING FAIRLY LIMITED. SATURDAY WILL FEATURE PARTLY SUNNY
CONDITIONS...BUT AGAIN WITH AREAS OF STRATUS LIKELY HOLDING ON
ESPECIALLY CENTRAL/ERN VT. HAVE STAYED NEAR MOS CONSENSUS ON HIGH
TEMPERATURES...AND TRENDED ABOVE MOS CONSENSUS ON LOW TEMPS DUE TO
POTENTIAL CLOUDINESS DURING FRIDAY AND SATURDAY NIGHT.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 228 PM EST THURSDAY...MODEL GUIDANCE CONTINUES TO SHOW
SURFACE HIGH PRESSURE ON SUNDAY WITH SHORTWAVE ENERGY MOVING
THROUGH THE AREA, INCREASING CLOUDS ACROSS THE NORTH COUNTRY. THE
SURFACE HIGH SHIFTS NORTHEASTWARD OVER THE CANADIAN MARITIMES,
WHICH WILL PUT THE NORTH COUNTRY IN SOUTH TO SOUTHWEST FLOW,
COINCIDING WITH SOME UPPER LEVEL RIDGING. THIS WILL RESULT IN
WARMING TEMPERATURES FROM MAXES OF MID TO UPPER 20S TO END THE
WEEKEND, TO LOW TO MID 30S TO BEGIN THE WORK WEEK.

AS A LARGE DEEPENING UPPER LEVEL TROUGH STRETCHES SOUTHWARD
ACROSS THE PLAINS, EDGING INTO THE TEXARKANA REGION, A WAVE AHEAD
OF THIS MAIN TROUGH WILL INCREASE THE THREAT OF SNOW SHOWERS
TRANSITIONING RAIN SHOWERS IN THE VALLEYS AS WE RESIDE IN THE WARM
SECTOR MONDAY NIGHT INTO TUESDAY. THE THREAT FOR HEAVIER/MORE
SIGNIFICANT PRECIPITATION INCREASES WEDNESDAY INTO WEDNESDAY NIGHT
AS THE UPPER TROUGH BECOMES NEGATIVELY TILTED AND THE ASSOCIATED
SFC LOW STRENGTHENS QUICKLY. TRACK OF UPPER LEVEL FEATURES AND
SURFACE FEATURES STILL UNDER DEBATE AMONG THE MODELS, BUT STRONG
WINDS ARE ASSOCIATED WITH THIS SYSTEM ARE PRESENT IN GFS AND
ECMWF...WITH 850 MB WINDS EXCEEDING 55 KTS. GFS BEING STRONGER AND
850MB WINDS EXCEED 65KTS IN AREAS. THIS MAY BE PROBLEMATIC ACROSS
THE SUMMITS AND NWRN SLOPES. THIS WILL BE A STORM TO KEEP AN EYE
ON AS IT DEVELOPS AND TRACKS TOWARD THE NE USA.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
THROUGH 06Z SATURDAY...PERSISTENT STRATUS DECK WILL BRING
PREDOMINANTLY MVFR CONDITIONS TO THE REGION THROUGH THE PERIOD.
PERIODS OF IFR ALSO EXPECTED AT MPV/SLK TONIGHT AND CONTINUING AT
SLK ON FRIDAY. PBG IS THE ONLY EXCEPTION WHERE SOME LOCAL
DOWNSLOPING HAS ALLOWED CEILINGS TO LIFT TO VFR AND THAT IS ALSO
EXPECTED TO CONTINUE THROUGH FRIDAY. SOME LIGHT SNOW SHOWERS
REMAIN AT BTV/SLK/MPV...AND WILL LIKELY CONTINUE THROUGH AT LEAST
12Z...POSSIBLY LASTING TO 15Z AT MPV/SLK. HOWEVER ANY SNOW SHOWERS
WILL BE LIGHT WITH ONLY MINOR VISIBILITY REDUCTIONS EXPECTED...IF
ANY AT ALL. COULD ALSO BE A FEW BRIEF PERIODS OF FREEZING DRIZZLE
AT SAME SITES OVERNIGHT.

NORTHWEST WINDS FROM 5 TO 10 KNOTS WILL CONTINUE OVERNIGHT AND
FRIDAY...EXCEPT LOCALLY WEST/SOUTHWEST AT MSS/SLK.

OUTLOOK 06Z SATURDAY THROUGH TUESDAY...

06Z SAT-00Z SUN...IMPROVING CONDITIONS...BUT CHANCE OF LINGERING
STRATUS IN SOME AREAS BRINGING PERIODS OF MVFR.

00Z SUN-00Z TUE...VFR UNDER HIGH PRESSURE.

00Z TUE-00Z WED...PERIODS OF MVFR IN LIGHT MIXED PRECIPITATION.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.

&&

$$
SYNOPSIS...BANACOS
NEAR TERM...JMG/NEILES
SHORT TERM...BANACOS
LONG TERM...KGM
AVIATION...RJS/MUCCILLI



AREA FORECAST DISCUSSION

NWS BURLINGTON VT

 1224 AM EST FRI DEC 19 2014

.SYNOPSIS...
BROAD CYCLONIC CIRCULATION SURROUNDING SLOW-MOVING LOW PRESSURE
OVER THE CANADIAN MARITIMES WILL MAINTAIN CLOUDY SKIES AND A FEW
MOUNTAIN SNOW SHOWERS TONIGHT. HIGH PRESSURE BUILDS ACROSS THE
NORTH COUNTRY FRIDAY AND THROUGH THE WEEKEND...BRINGING GENERALLY
DRY WEATHER CONDITIONS...THOUGH SKIES WILL REMAIN VARIABLY CLOUDY
OWING TO LOW STRATUS. THE NEXT SIGNIFICANT STORM SYSTEM ARRIVES
FOR CHRISTMAS EVE WITH VERY WINDY AND MILD CONDITIONS...WITH
PERIODS OF MODERATE TO BRIEFLY HEAVY RAIN. BRISK AND SOMEWHAT
COLDER CONDITIONS ARE EXPECTED FOR CHRISTMAS DAY...WITH A
TRANSITION TO SNOW SHOWERS POSSIBLE...ESPECIALLY OVER THE HIGHER
TERRAIN.

&&

.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 1221 AM EST FRIDAY...NO SIGNIFICANT ADJUSTMENTS FOR 1230
UPDATE. PATCHY -FZDZ HAS MATERIALIZED ACROSS PORTIONS OF NRN NY
AND CENTRAL/NRN VT OVER THE PAST 3 HOURS AS PRIMARY DENDRITIC SNOW
GROWTH LAYERS ARE TRENDING UNSATURATED. THIS HAS BEEN PICKED UP
QUITE WELL ON THIS EVENING`S RAP SOUNDING PROFILES AND HAVE ISSUED
SPECIAL WEATHER STATEMENTS TO HIGHLIGHT POTENTIAL LIGHT GLAZE
ICING ON UNTREATED/ELEVATED SURFACES OVERNIGHT. OTHERWISE FORECAST
REMAINS IN GOOD SHAPE AS BLOCKED MOIST NORTHWESTERLY FLOW
CONTINUES ACROSS THE AREA. OTHER THAN THE PATCHY -FZDZ AND SOME
PASSING FLURRIES/LIGHT SHSN ACTIVITY OVERNIGHT...A GENERALLY
CLOUDY NIGHT IS EXPECTED AS TEMPERATURES SETTLE INTO THE LOWER AND
MID 20S BY SUNRISE FRIDAY. HAVE A GREAT NIGHT.

&&

.SHORT TERM /7 AM THIS MORNING THROUGH SATURDAY NIGHT/...
AS OF 230 PM EST THURSDAY...RELATIVELY TRANQUIL SHORT-TERM
PERIOD...ONLY ISSUE WILL BE EXTENT OF STRATUS AND ASSOCIATED
IMPACT ON RADIATIVE HEATING/COOLING AND TEMPERATURES. HIGH
PRESSURE CENTERED ACROSS THE GREAT LAKES FRIDAY DRIFTS ACROSS THE
NERN CONUS AND SERN CANADA SATURDAY AND SATURDAY NIGHT. THIS WILL
BRING LIGHT WINDS...ESPECIALLY ON SATURDAY. 12Z NAM HAS TRENDED
TOWARD HIGHER LOW-LEVEL RH FOR FRIDAY. WITH WEAK WIND FIELDS AND
LOW-LEVEL INVERSION LAYER/LOW SUN ANGLE...WILL KEEP ANY PARTIAL
CLEARING FAIRLY LIMITED. SATURDAY WILL FEATURE PARTLY SUNNY
CONDITIONS...BUT AGAIN WITH AREAS OF STRATUS LIKELY HOLDING ON
ESPECIALLY CENTRAL/ERN VT. HAVE STAYED NEAR MOS CONSENSUS ON HIGH
TEMPERATURES...AND TRENDED ABOVE MOS CONSENSUS ON LOW TEMPS DUE TO
POTENTIAL CLOUDINESS DURING FRIDAY AND SATURDAY NIGHT.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 228 PM EST THURSDAY...MODEL GUIDANCE CONTINUES TO SHOW
SURFACE HIGH PRESSURE ON SUNDAY WITH SHORTWAVE ENERGY MOVING
THROUGH THE AREA, INCREASING CLOUDS ACROSS THE NORTH COUNTRY. THE
SURFACE HIGH SHIFTS NORTHEASTWARD OVER THE CANADIAN MARITIMES,
WHICH WILL PUT THE NORTH COUNTRY IN SOUTH TO SOUTHWEST FLOW,
COINCIDING WITH SOME UPPER LEVEL RIDGING. THIS WILL RESULT IN
WARMING TEMPERATURES FROM MAXES OF MID TO UPPER 20S TO END THE
WEEKEND, TO LOW TO MID 30S TO BEGIN THE WORK WEEK.

AS A LARGE DEEPENING UPPER LEVEL TROUGH STRETCHES SOUTHWARD
ACROSS THE PLAINS, EDGING INTO THE TEXARKANA REGION, A WAVE AHEAD
OF THIS MAIN TROUGH WILL INCREASE THE THREAT OF SNOW SHOWERS
TRANSITIONING RAIN SHOWERS IN THE VALLEYS AS WE RESIDE IN THE WARM
SECTOR MONDAY NIGHT INTO TUESDAY. THE THREAT FOR HEAVIER/MORE
SIGNIFICANT PRECIPITATION INCREASES WEDNESDAY INTO WEDNESDAY NIGHT
AS THE UPPER TROUGH BECOMES NEGATIVELY TILTED AND THE ASSOCIATED
SFC LOW STRENGTHENS QUICKLY. TRACK OF UPPER LEVEL FEATURES AND
SURFACE FEATURES STILL UNDER DEBATE AMONG THE MODELS, BUT STRONG
WINDS ARE ASSOCIATED WITH THIS SYSTEM ARE PRESENT IN GFS AND
ECMWF...WITH 850 MB WINDS EXCEEDING 55 KTS. GFS BEING STRONGER AND
850MB WINDS EXCEED 65KTS IN AREAS. THIS MAY BE PROBLEMATIC ACROSS
THE SUMMITS AND NWRN SLOPES. THIS WILL BE A STORM TO KEEP AN EYE
ON AS IT DEVELOPS AND TRACKS TOWARD THE NE USA.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
THROUGH 00Z SATURDAY...PERSISTENT STRATUS DECK WILL BRING
PREDOMINANTLY MVFR CONDITIONS TO THE REGION THROUGH THE PERIOD.
WIDESPREAD MVFR CONDITIONS EXIST THIS EVENING AND WILL CONTINUE
THROUGH TONIGHT AND ON FRIDAY. PERIODS OF IFR ALSO EXPECTED AT
MPV/SLK TONIGHT AND CONTINUING AT SLK FOR FRIDAY. PBG IS THE ONLY
EXCEPTION WHERE SOME LOCAL DOWNSLOPING HAS ALLOWED CEILINGS TO
LIFT TO VFR THIS EVENING AND THAT IS ALSO EXPECTED TO CONTINUE
THROUGH FRIDAY. SOME LIGHT SNOW SHOWERS REMAIN AT
BTV/SLK/MPV...AND WILL LIKELY CONTINUE THROUGH AT LEAST
06Z...POSSIBLY LASTING TO 12Z AT MPV/SLK. HOWEVER ANY SNOW SHOWERS
WILL BE LIGHT WITH ONLY MINOR VISIBILITY REDUCTIONS EXPECTED...IF
ANY AT ALL.

NORTHWEST WINDS FROM 5 TO 10 KNOTS WILL CONTINUE THROUGH TONIGHT
AND FRIDAY...EXCEPT LOCALLY WEST/SOUTHWEST AT MSS/SLK.

OUTLOOK 00Z SATURDAY THROUGH TUESDAY...

00Z SAT-00Z SUN...IMPROVING CONDITIONS...BUT CHANCE OF LINGERING
STRATUS IN SOME AREAS BRINGING PERIODS OF MVFR.

00Z SUN-00Z TUE...VFR UNDER HIGH PRESSURE.

00Z TUE-00Z WED...PERIODS OF MVFR IN LIGHT MIXED PRECIPITATION.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.

&&

$$
SYNOPSIS...BANACOS
NEAR TERM...JMG/NEILES
SHORT TERM...BANACOS
LONG TERM...KGM
AVIATION...MUCCILLI



AREA FORECAST DISCUSSION

NWS BISMARCK ND

 405 AM CST FRI DEC 19 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 405 AM CST FRI DEC 19 2014

FOG AND LOW CLOUDS ARE THE MAIN CONCERNS IN THE SHORT TERM.

CURRENT SURFACE ANALYSIS  INDICATES LOW PRESSURE IN THE LEE OF THE
ROCKIES WITH A TROUGH EXTENDING FROM NORTHERN ALBERTA TO THE WESTERN
DAKOTAS. AT UPPER LEVELS A BROAD TROUGH EXTENDED OVER THE CANADIAN
AND NORTHERN US PLAINS. A RATHER SHARP WESTERN EDGE TO LOW CLOUDS
EXTENDED FROM NEAR WILLISTON ACROSS LAKE SAKAKAWEA TO EAST OF
BISMARCK. MID LEVEL CLOUDS WERE ALONG AND SOUTH/WEST OF THE MISSOURI
RIVER AT 3 AM CST. EXPECT THE LOW CLOUDS TO CLEAR FROM WEST TO EAST
ACROSS SOUTH CENTRAL NORTH DAKOTA...BUT LATEST HRRR MODEL INDICATES
CLOUDS HANGING IN ACROSS THE NORTH. A SHORTWAVE ALOFT ON THE WESTERN
EDGE OF THE UPPER TROUGH WAS DIGGING SOUTHEAST ACROSS SOUTHWESTERN
NORTH DAKOTA INTO WESTERN SOUTH DAKOTA...AND MAY BE THE DRIVING
FORCE FOR THE MID CLOUDS MOVING IN AND THE LOWER CLOUDS DISSIPATING.

DENSE FOG STILL EVIDENT AT WILLISTON...ALTHOUGH VISIBILITIES HAVE
IMPROVED IN THE LAST HOUR AT OTHER PLACES WITHIN THE DENSE FOG
ADVISORY...SUCH AS TIOGA/STANLEY/CROSBY. BUT MINOT VISIBILITY IS ON
A DOWNWARD TREND. THUS WILL KEEP THE DENSE FOG ADVISORY GOING UNTIL
6 AM AND THEN RE-EVALUATE.

OTHERWISE WARM ADVECTION TODAY SHOULD ALLOW TEMPERATURES TO RISE
INTO THE MID/UPPER 20S NORTH AND EAST OF THE MISSOURI RIVER...AND
WELL INTO THE MID AND UPPER 30S SOUTH AND WEST OF THE RIVER. TONIGHT
A SHORTWAVE RIDGE ALOFT ENTERS WESTERN NORTH DAKOTA AHEAD OF AN
UPPER LEVEL SHORTWAVE MOVING EASTWARD OUT OF THE ROCKIES. LOWS
TONIGHT SHOULD REMAIN ABOVE AVERAGE IN THE TEENS AND LOWER 20S.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 405 AM CST FRI DEC 19 2014

THE SHORT TERM ISSUES...LOW CLOUDS AND LIGHT PRECIPITATION
INCLUDING FREEZING RAIN/FREEZING DRIZZLE AND PATCHY FOG...
CONTINUE INTO THE LONG TERM AS THE FORECAST AREA REMAINS UNDER A
MEAN TROUGH SURFACE AND ALOFT. WAVES COMING THROUGH SATURDAY AND
AGAIN SUNDAY ARE WEAK AND MOISTURE STARVED. HOWEVER...WITH WARMER
AIR ADVECTING IN ALOFT AHEAD OF EACH WAVE THERE IS A RISK OF
FREEZING RAIN SATURDAY MORNING / FREEZING DRIZZLE WITH LOW STRATUS
CLOUDS. WARM ADVECTION CONTINUES CHANGING ANY PRECIPITATION IN THE
SOUTHWEST TO RAIN WITH SURFACE TEMPERATURES INTO THE MID 30S
SATURDAY AFTERNOON. A SIMILAR SCENARIO SETS UP FOR SUNDAY.

THE MID LEVEL LOW...CUTTING OFF OVER WISCONSIN...WILL BLOCK THE
FLOW PATTERN UP ACROSS THE NORTHERN PLAINS. THIS WILL ALLOW COLDER
AIR TO SPILL IN FOR TUESDAY. LOOKING AHEAD TO CHRISTMAS DAY...THE
LOW TO THE EAST...AND HIGH PRESSURE MOVING ACROSS THE NORTHERN
ROCKIES...ALLOW A STEADY FLOW OF COLDER AIR INTO NORTH
DAKOTA...THAT WILL CONTINUE AT LEAST THROUGH THE HOLIDAY WEEKEND.
STILL THOUGH...TEMPERATURES ARE CLOSE TO WHAT IS NORMAL FOR THE
END OF DECEMBER...AROUND 20 DAYTIME AND SINGLE DIGITS ABOVE AND
BELOW AT NIGHT. PERIODS OF FLURRIES...MAYBE A FEW TENTHS INCH OF
SNOW AT MOST EVERY OTHER DAY OR SO...LOOKS TO OCCUR THROUGH THE
CHRISTMAS HOLIDAY WEEKEND.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1245 AM CST FRI DEC 19 2014

A MOIST SOUTHERLY FLOW CONTINUES TO PRODUCE WIDESPREAD MVFR-IFR
STRATUS ACROSS CENTRAL AND NORTHWEST NORTH DAKOTA. A WEAK TROUGH OF
LOW PRESSURE...WITH A SOUTHWEST FLOW BEHIND IT...IS IS PROVIDING
CLEARING SKIES ACROSS SOUTHWEST NORTH DAKOTA. THIS TROUGH WILL CLEAR
THE STRATUS AT KBIS AND POSSIBLY KISN AROUND 06 UTC. HOWEVER...WITH
THE CLEAR SKIES AREAS OF FOG WITH IFR CIGS/VSBYS WILL BE POSSIBLE AT
THESE SITES THROUGH EARLY MORNING FRIDAY. KMOT AND KJMS WILL REMAIN
IN MVFR-IFR STRATUS INTO FRIDAY MORNING. KJMS SHOULD CLEAR DURING
THE MORNING BUT THE MOISTURE REMAINS TRAPPED ALONG THE CANADIAN
BORDER WHICH COULD KEEP KMOT IN THE MVFR-IFR STRATUS AT LEAST
THROUGH MIDDAY FRIDAY. ONCE THE STRATUS CLEARS THE TAF SITES...AND
THE THREAT OF PATCHY MORNING FOG HAS ENDED...VFR CONDITIONS ARE THEN
EXPECTED THROUGH THE REMAINDER OF THE FORECAST PERIOD. WINDS WILL
REMAIN LIGHT FROM THE SOUTH TO SOUTHWEST.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
NDZ001>003-009>011.

&&

$$

SHORT TERM...JV
LONG TERM...JPM
AVIATION...TWH






AREA FORECAST DISCUSSION

NWS BISMARCK ND

 1245 AM CST FRI DEC 19 2014

.UPDATE...
ISSUED AT 1245 AM CST FRI DEC 19 2014

DENSE FOG HAD DEVELOPED OVER NORTHEASTERN MONTANA AND HAD SPREAD
INTO NORTHWESTERN NORTH DAKOTA. HRRR SHORT TERM MODEL SUGGESTS LOW
VISIBILITIES ALSO FARTHER EAST TOWARDS THE MINOT AREA. THEREFORE
HAVE ISSUED A DENSE FOG ADVISORY FOR DIVIDE AND WILLIAMS
COUNTIES...BURKE AND MOUNTRAIL COUNTIES...AND RENVILLE AND WARD
COUNTIES UNTIL 6 AM CST. WATFORD CITY HAD REPORTED 1/4 MILE
VISIBILITY...BUT LATEST SATELLITE PICS SHOWED A TREND OF MID
CLOUDS MOVING EASTWARD OUT OF MONTANA - WHICH WOULD HELP BREAK UP
FOG SOUTH OF THE MISSOURI RIVER. THUS KEPT THOSE COUNTIES SOUTH OF
THE MISSOURI OUT OF THE DENSE FOG ADVISORY. OTHERWISE CURRENT
FORECAST ON TRACK.

UPDATE ISSUED AT 957 PM CST THU DEC 18 2014

ONLY SOME MINOR UPDATES LATE THIS EVENING. ADDED A MENTION OF FOG
MOST EVERYWHERE EXCEPT THE FAR SOUTHWEST. FOG IS BECOMING MORE
PREVALENT OVER THE NORTHEAST CWA. STILL THINK AREAS JUST WEST OF
THE CLEARING WILL FOG IN A LITTLE ALSO. UPDATED TEMPERATURES BASED
ON LATEST OBSERVATIONS.

UPDATE ISSUED AT 810 PM CST THU DEC 18 2014

AREA OF SNOW SHOWERS WILL MOVE OUT OF EASTERN DICKEY/LAMOURE
COUNTIES DIRECTLY. OTHERWISE STRATUS REMAINS ACROSS MUCH OF
WESTERN AND CENTRAL NORTH DAKOTA. A FEW REPORTS OF VERY LIGHT
FREEZING DRIZZLE THIS EVENING...AND DONT THINK FZDZ CAN BE RULED
OUT ANYWHERE WE HAVE THE STRATUS. THUS HAVE ADDED A MENTION OF
PATCHY FREEZING DRIZZLE...ALONG WITH SCATTERED FLURRIES WHEREVER
WE HAVE THE LOW STRATUS. THIS IS MAINLY ALONG AND TO THE NORTH AND
EAST OF LAKE SAKAKAWEA AND THE MISSOURI RIVER. SKIES HAVE CLEARED
OVER MOST OF SOUTHWEST NORTH DAKOTA. HOWEVER WITH ABUNDANT LOW
LEVEL MOISTURE REMAINING...WILL MENTION PATCHY FOG OVER A GOOD
PORTION OF THE SOUTHWEST. DICKINSON CLEARED OUT AND DROPPED DOWN
TO A QUARTER MILE BRIEFLY...BEFORE SETTLING AROUND 3SM. ALSO
ADJUSTED TEMPERATURES UP ACROSS THE NORTH CENTRAL THROUGH THE
JAMES RIVER VALLEY. STRATUS IS EXPECTED TO REMAIN HERE THROUGH THE
NIGHT...WHICH SHOULD HOLD TEMPERATURES FAIRLY STEADY. TEMPERATURES
WERE LOWERED OVER PORTIONS OF THE SOUTHWEST WHERE SKIES HAVE
CLEARED.

UPDATE ISSUED AT 602 PM CST THU DEC 18 2014

ONLY A COUPLE MINOR CHANGES TO THE EARLY EVENING UPDATE. LOWERED
CLOUD COVER OVER THE SOUTHWEST WHERE LOW STRATUS HAS CLEARED. ALSO
REMOVED MENTION OF FLURRIES FOR THIS AREA. ADJUSTED MENTION OF
FREEZING DRIZZLE A LITTLE NORTH INTO STUTSMAN COUNTY OVER THE
SOUTHEAST CWA THROUGH 9 PM CENTRAL BASED ON CURRENT RADAR RETURNS.
OTHERWISE NO SIGNIFICANT CHANGES.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 332 PM CST THU DEC 18 2014

CURRENT SURFACE ANALYSIS PLACES TROUGH DROPPING DOWN FROM NEAR THE
ALBERTA/SASKATCHEWAN LINE TOWARDS THE WESTERN DAKOTAS. UPPER LEVEL
ANALYSIS PLACES UPPER LOW PUSHING THROUGH EASTERN NORTH DAKOTA.
SOME LIGHT SNOW WITH THIS SYSTEM CONTINUES OVER PORTIONS OF SOUTH
CENTRAL NORTH DAKOTA SLIDING INTO THE JAMES RIVER VALLEY.

FOR TONIGHT...BROAD LAYER OF LOW CLOUD COVER WILL SLOWLY ERODE
OVER THE SOUTHWEST...THOUGH WILL REMAIN IN PLACE OVER REMAINING
AREAS. SOME FLURRIES WILL BE POSSIBLE...WHILE OVER THE FAR
SOUTHERN JAMES RIVER VALLEY FORECAST SOUNDINGS SUGGEST THERE MAY
BE A BRIEF PERIOD OF VERY LIGHT FREEZING DRIZZLE EARLY THIS EVENING.

ON FRIDAY...QUIET WEATHER IS EXPECTED WITH CLOUDS SLOWLY ERODING
AS WEAK RIDGE MAKES ITS APPROACH. WARMER AIR WILL CONTINUE TO
PUSH INTO THE AREA BRINGING TEMPERATURES NEAR TO SLIGHTLY ABOVE
AVERAGE.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED A 332 PM CST THU DEC 18 2014

FOCUS IN THE LONG TERM IS ON THE WEAK SHORTWAVE ON SATURDAY AND THEN
THE LARGE TROUGH SETTING UP OVER THE CENTRAL CONUS SUNDAY INTO NEXT
WEEK.

A WEAK SHORTWAVE IS FORECAST TO MOVE EASTWARD ACROSS THE STATE
SATURDAY. THE 12 UTC MODEL GUIDANCE SHOWS VERY SCATTERED
PRECIPITATION ACROSS THE STATE...HOWEVER PAST MODEL RUNS AND CURRENT
GUIDANCE SHOWS THE BEST CHANCE...ONLY SLIGHT...OVER NORTHWEST NORTH
DAKOTA INTO EASTERN MONTANA. A WEAK SURFACE WARM FRONT WILL
ACCOMPANY THE SHORTWAVE...FOLLOWED QUICKLY BY A WEAK COLD FRONT.
EARLY IN THE DAY SATURDAY THE WARM LAYER ALOFT MAY MELT THE
SNOW...HOWEVER BELOW FREEZING TEMPERATURES AT THE SURFACE WILL MOST
LIKELY REFREEZE THE PRECIPITATION INTO SLEET. AS THE DAY PROGRESSES
THE WARM LAYER ALOFT WILL COOL TO BELOW FREEZING AND SURFACE
TEMPERATURES WILL ACTUALLY WARM TO ABOVE FREEZING...CAUSING ANY
FALLING PRECIPITATION TO TRANSITION TO A MIXTURE OF FREEZING
RAIN...SNOW...AND RAIN. WITH ALL THAT SAID ACCUMULATIONS OF ANY KIND
ARE EXPECTED TO BE VERY LIGHT...WITH MINIMAL IMPACTS.

A MORE SIGNIFICANT TROUGH DEVELOPS OVER THE DAKOTAS SUNDAY...DEEPENS
AND PROPAGATES EAST INTO MINNESOTA AND THE GREAT LAKES REGION MONDAY
INTO NEXT WEEK. WARM ADVECTION AHEAD OF THE SYSTEM AND COLD
ADVECTION BEHIND IT WILL BRING MORE CHANCES OF A WINTRY MIX OF
SLEET...FREEZING RAIN OR DRIZZLE...RAIN...AND SNOW TO NORTH DAKOTA
ON SUNDAY AND MONDAY. ALTHOUGH TEMPERATURES FOR MOST OF NORTH DAKOTA
WILL BE BELOW FREEZING...THE LACK OF ICE CRYSTALS IN CLOUDS MAY
CAUSE PRECIPITATION TO FALL AS FREEZING RAIN OR DRIZZLE. ONCE AGAIN
ANY ACCUMULATIONS ARE EXPECTED TO BE LIGHT OVER WESTERN AND CENTRAL
NORTH DAKOTA...HOWEVER MODELS HAVE CONTINUED TO STRENGTHEN THIS
SYSTEM OVER THE PAST FEW DAYS AND IT WILL HAVE TO BE WATCHED CLOSELY
TO SEE IF ANY MORE PRECIPITATION IS PUSHED INTO NORTH DAKOTA.

AS THE TROUGH PROPAGATES TOWARD THE EAST COAST NORTHWEST FLOW WILL
SET UP OVER NORTH DAKOTA. TEMPERATURES WILL PROGRESSIVELY GET COLDER
WITH A MORE ACTIVE WEATHER PATTERN IN STORE FOR THE NORTHERN PLAINS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1245 AM CST FRI DEC 19 2014

A MOIST SOUTHERLY FLOW CONTINUES TO PRODUCE WIDESPREAD MVFR-IFR
STRATUS ACROSS CENTRAL AND NORTHWEST NORTH DAKOTA. A WEAK TROUGH OF
LOW PRESSURE...WITH A SOUTHWEST FLOW BEHIND IT...IS IS PROVIDING
CLEARING SKIES ACROSS SOUTHWEST NORTH DAKOTA. THIS TROUGH WILL CLEAR
THE STRATUS AT KBIS AND POSSIBLY KISN AROUND 06 UTC. HOWEVER...WITH
THE CLEAR SKIES AREAS OF FOG WITH IFR CIGS/VSBYS WILL BE POSSIBLE AT
THESE SITES THROUGH EARLY MORNING FRIDAY. KMOT AND KJMS WILL REMAIN
IN MVFR-IFR STRATUS INTO FRIDAY MORNING. KJMS SHOULD CLEAR DURING
THE MORNING BUT THE MOISTURE REMAINS TRAPPED ALONG THE CANADIAN
BORDER WHICH COULD KEEP KMOT IN THE MVFR-IFR STRATUS AT LEAST
THROUGH MIDDAY FRIDAY. ONCE THE STRATUS CLEARS THE TAF SITES...AND
THE THREAT OF PATCHY MORNING FOG HAS ENDED...VFR CONDITIONS ARE THEN
EXPECTED THROUGH THE REMAINDER OF THE FORECAST PERIOD. WINDS WILL
REMAIN LIGHT FROM THE SOUTH TO SOUTHWEST.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
NDZ001>003-009>011.

&&

$$

UPDATE...JV
SHORT TERM...JJS
LONG TERM...MM
AVIATION...TWH






AREA FORECAST DISCUSSION

NWS WILMINGTON OH

 109 AM EST FRI DEC 19 2014

.SYNOPSIS...
WEAK SURFACE HIGH PRESSURE WILL PUSH SLOWLY EAST ACROSS THE
REGION THROUGH THE WEEKEND...LEADING TO PRIMARILY DRY CONDITIONS
AND NEAR NORMAL TEMPERATURES.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS THE SURFACE PRESSURE GRADIENT CONTINUES TO RELAX ACROSS THE
OHIO VALLEY...ASCENT FROM A WEAKENING MID-LEVEL WAVE IS ALSO
MOVING OFF TO THE EAST. THIS IS LEADING TO A DIMINISHING TREND IN
RADAR ECHOES...AND FLURRIES OVER THE ILN FORECAST AREA HAVE JUST
ABOUT ENDED.

FORECAST TRENDS ARE RIGHT ON TRACK...AND MIN TEMPS WERE NOT
ADJUSTED AT ALL. THE CLOUD FORECAST IS SIMILAR TO YESTERDAY...BUT
THERE HAS BEEN SOME EROSION IN THE LOWEST LAYER OF CLOUDS
(1500-2500 FEET) IN THE SOUTHERN HALF OF THE FORECAST AREA. THE
00Z KILN SOUNDING DOES NOT SHOW A WELL-DEFINED LAYER OF SATURATION
BELOW 800MB AS HAS BEEN THE CASE FOR THE PAST SEVERAL SOUNDINGS.
REGARDLESS...MID-LEVEL CLOUDS (6000-1000 FEET) ARE FAIRLY
THICK...AND SKY GRIDS REMAIN AT 90-100 PERCENT THROUGH THE
OVERNIGHT.

PREVIOUS DISCUSSION >
UPR LVL S/WV WILL PASS EAST ACRS OUR REGION THROUGH THIS EVENING.
FORCING IS WEAK WITH MOST AREAS JUST SEEING A FEW FLURRIES. THERE
COULD BE A FEW SNOW SHOWERS WITH JUST A LIGHT DUSTING ALONG THE
I-70 CORRIDOR WHERE DEEPEST MOISTURE WILL INTERSECT WEAK FORCING.
LOW LEVEL CLOUDS WILL CONTINUE TO BE AN ISSUE AS THE RAP MODEL
SHOWS REGION STAYING PRETTY MUCH OVERCAST OVERNIGHT. LOWS WILL
DROP INTO THE LOWER AND MID 20S.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/...
WEAK SFC HIGH PRESSURE WILL SLOWLY BUILD INTO THE AREA ON FRIDAY.
DESPITE THIS FEATURE...IT LOOKS LIKE LOW LEVEL MOISTURE WILL HANG
AROUND AS IT BECOMES TRAPPED UNDERNEATH THE HIGH. WILL CONTINUE
WITH MAINLY CLOUDY SKIES. HIGHS WILL RANGE FROM THE LOWER TO MID
30S.

FOR FRIDAY NIGHT INTO SATURDAY...LATEST MODEL FORECASTS KEEP THE
AFFECTS OF AN UPR LVL S/WV TO OUR SOUTH WHILE SFC RIDGING REMAINS
IN PLACE. IT IS DIFFICULT TO KNOW IF THE LOW LEVEL CLOUDS WILL
ERODE DURING THIS TIME FRAME. HOWEVER...WITH AN INCREASE IN MID
AND HIGH LEVEL MOISTURE...IT WILL LIKELY REMAIN MOSTLY CLOUDY. IT
WILL BE A LITTLE WARMER ON SATURDAY WITH HIGHS IN THE MID AND
UPPER 30S.

BY SATURDAY NIGHT...HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS
THE GREAT LAKES AND OHIO VALLEY WHILE A WEAK UPR LVL S/WV PASSES
ACRS THE SOUTHERN GREAT LAKES. PARTLY CLOUDY SKIES ARE EXPECTED.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE CENTERED TO THE NORTHEAST WILL BRING DRY WEATHER ON
SUNDAY. INCREASING MOISTURE AND LIFT WELL AHEAD OF DEVELOPING LOW
PRESSURE MAY PRODUCE LIGHT RAIN AND SNOW ON MONDAY. AS THE LOW MOVES
TO LAKE MICHIGAN ON TUESDAY...RAIN WILL BE LIKELY IN A CONCENTRATED
BAND OF ISENTROPIC LIFT EXTENDING SOUTHEAST FROM THE LOW CENTER.

ENERGY WILL TRANSFER TO A COASTAL LOW ON WEDNESDAY...LEAVING THE
AREA IN A BRISK AND COLDER NORTHWEST FLOW OF DECREASING MOISTURE AND
FORCING. THIS WILL BRING AN END TO STEADY RAIN AND SNOW...WITH
SCATTERED SNOW SHOWERS THEN LINGERING INTO THURSDAY. NORTHERN
LOCATIONS SEEM TO HAVE THE BEST CHANCE FOR LIGHT SNOW ACCUMULATIONS.

AFTER NEAR NORMAL HIGHS AROUND 40 ON SUNDAY...WARM ADVECTION AHEAD
OF THE LOW WILL ALLOW ABOVE NORMAL HIGHS IN THE 40S ON MONDAY AND
TUESDAY. EXPECT EARLY HIGHS NEAR 40 ON WEDNESDAY...DROPPING TO
BELOW NORMAL 30S UNDER COLD ADVECTION ON THURSDAY.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE WILL ALLOW FOR DRY CONDITIONS ACROSS THE TAF SITES
THROUGH THE TAF PERIOD. MVFR TO VFR CIGS CAN BE EXPECTED
THROUGH THE TAF PERIOD. SOME BRIEF MVFR VSBYS WILL BE POSSIBLE
OVERNIGHT. ONLY INCLUDED MVFR VSBYS AT KCMH WHERE THERE IS A
BETTER CHANCE OF THEM OCCURRING.

OUTLOOK...MVFR CEILINGS AND VISIBILITIES ARE POSSIBLE ON
SATURDAY.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

&&

$$

SYNOPSIS...HICKMAN/NOVAK
NEAR TERM...HATZOS/HICKMAN
SHORT TERM...HICKMAN
LONG TERM...CONIGLIO
AVIATION...NOVAK






AREA FORECAST DISCUSSION

NWS SIOUX FALLS SD

 1050 PM CST THU DEC 18 2014

.UPDATE...
ISSUED AT 830 PM CST THU DEC 18 2014

WITH THE CLOUD DECK HANGING IN THE NEIGHBORHOOD OF 1000-1500
FEET...THE CLOUD DECK IS RELATIVELY SHALLOW AND WILL BE DIFFICULT
TO GET DROPLET PRODUCTION. HAVE THEREFORE REMOVED PRECIP THROUGH
THE OVERNIGHT...HOWEVER...AM STILL CONCERNED ABOUT FOG POTENTIAL
ACROSS SOUTH CENTRAL SOUTH DAKOTA. BOTH HI RES HRRR AND THE RAP
SUGGEST FOG POTENTIAL...SO HAVE RAISED FOG MENTION AFTER 06Z
WELL INTO FRIDAY MORNING ALONG THE MISSOURI RIVER VALLEY IN
CENTRAL SOUTH DAKOTA.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 348 PM CST THU DEC 18 2014

STRATUS CURRENTLY COVERING THE ENTIRE REGION...AND THINK THE CLOUDS
STAY LOCKED IN THROUGH THE NIGHT AND INTO TOMORROW. CLEARING LINE IN
CENTRAL SOUTH DAKOTA WILL PROBABLY APPROACH OUR FAR WESTERN AREAS
SUCH AS GREGORY AND BRULE COUNTIES. SO COULD SEE SOME CLEARING THERE
LATER TONIGHT...AND SOME SUN IN THOSE LOCATIONS TOMORROW. THIS IS
THE AREA THAT COULD SEE SOME FOG DEVELOPMENT LATER TONIGHT IF THEY
ARE ABLE TO CLEAR...SO ADDED IN FOG MENTION. THE REST OF THE AREA
WILL STAY LOCKED IN THE LOW CLOUDS THROUGH TOMORROW...WITH NOTHING
ABLE TO SCOUR OUT THE LOW LEVEL MOISTURE. GIVEN THE CLOUD
COVER...RAISED LOWS TONIGHT...AS DO NOT THINK TEMPERATURES WILL BE
ABLE TO FALL MORE THAN A FEW DEGREES FROM CURRENT READINGS.

ONE QUESTION IS WHETHER WE ARE ABLE TO GET ANY FLURRIES OUT OF THE
STRATUS TONIGHT. MODELS SUGGEST MOISTURE LAYER DEEPENS ENOUGH FOR
THIS TO BE A POSSIBILITY...BUT MOISTURE DEPTH AND SATURATION BOTH
SEEM BORDERLINE. EXPECT CLOUD TOP TEMPERATURES TO BE RIGHT AROUND
-7C TO -10C...RIGHT ON THE EDGE OF ICE PRODUCTION. THUS CAN NOT RULE
OUT A LITTLE LIGHT FREEZING DRIZZLE AS WELL. MOISTURE DEPTH LOOKS TO
DECREASE FROM WEST TO EAST THROUGH THE NIGHT...SO THINK THE LIGHT
PRECIP THREAT SHOULD WANE BY MORNING. WILL NEED TO KEEP AN EYE ON
THINGS...BUT AT THIS TIME THINK THAT EVEN IF WE DO GET FREEZING
DRIZZLE...IT WILL NOT BE HEAVY ENOUGH TO CAUSE MUCH OF AN ISSUE.
OTHERWISE CLOUDY BUT SLIGHTLY WARMER CONDITIONS TOMORROW. CLOUDS
WILL PREVENT US FROM WARMING TOO MUCH...BUT STILL THINKING WE GET
INTO THE LOW TO MID 30S.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 348 PM CST THU DEC 18 2014

MOIST LOW LEVEL FLOW WILL CONTINUE TO BRING LOW STRATUS TO THE BULK
OF THE FORECAST AREA FRIDAY NIGHT THROUGH SATURDAY NIGHT. SOME
DECEASE IN CLOUD COVERAGE WILL BE POSSIBLE ON SATURDAY...
PARTICULARLY IN THE WEST WHERE TEMPERATURES WILL QUICKLY WARM INTO
THE MID AND UPPER 30S AND MAY SOAR EVEN HIGHER IF SUBSTANTIAL
CLEARING DOES OCCUR. WITHOUT MUCH LIFT IN THE CLOUD
LAYER...MEASURABLE PRECIPITATION IS NOT EXPECTED. CANNOT RULE OUT
SOME PATCHY DRIZZLE/FREEZING DRIZZLE POTENTIAL...BUT WITH CLOUD TOPS
TOO WARM FOR ICE CRYSTAL GROWTH...FLURRIES ARE NOT EXPECTED. MODEL
SOUNDINGS SUGGEST THAT THE CLOUD DEPTH IS A BIT TOO MARGINAL FOR
WIDESPREAD DRIZZLE OR FREEZING DRIZZLE...WITH THE EXCEPTION OF PARTS
OF NORTHWEST IOWA ON SATURDAY NIGHT. SURFACE TEMPERATURES WILL BE IN
THE UPPER 20S AT THIS TIME...SO WILL LEAVE MENTION OF PATCHY
FREEZING DRIZZLE.

POTENT STORM SYSTEM BEGINS TAKING SHAPE OVER THE NORTHERN PLAINS
SUNDAY AFTERNOON AS A TROUGH EMERGES FROM THE CANADIAN ROCKIES AND
DIGS INTO NORTH DAKOTA. STILL LOOKING AT SOME FAIRLY SIGNIFICANT
MODEL DIFFERENCES REGARDING THE TRACK AND TIMING...SO CONFIDENCE IN
TEMPERATURE TRENDS AND PRECIPITATION TIMING IS SOMEWHAT LOW. IT DOES
LOOK LIKE AN INITIAL WAVE SWINGS INTO THE AREA SUNDAY NIGHT...WITH
THE GEM AND NAM AROUND 6 TO 12 HOURS FASTER THAN THE ECMWF AND GFS.
WITH THIS WAVE SOME BROAD LIFT NOSES INTO THE AREA AND SHOULD ALLOW
SOME LIGHT PRECIPITATION TO FORM MAINLY ACROSS THE EASTERN HALF.
SURFACE TEMPERATURES COOL WHILE THE MILD AIR ALOFT ERODES. EXPECT A
WINTRY MIX OF PRECIPITATION...WITH SNOW...SLEET AND FREEZING RAIN
POSSIBLE. WITH THE BETTER FORCING LIKELY TO OUR EAST...ANY
PRECIPITATION WILL BE VERY LIGHT AND PRELIMINARILY IT LOOKS LIKE
SNOW AND ICE AMOUNTS WOULD BE VERY MINIMAL.

SECONDARY WAVE FOLLOWS QUICKLY ON MONDAY...SLOWS AND DEEPENS OVER
THE MID AND NORTHERN MISSISSIPPI VALLEY INTO MONDAY NIGHT. THE GEM
IS THE OUTLIER WITH A WEAKER OPEN WAVE AND WAS THEREFORE DISCARDED.
THE LATEST GFS AND ECMWF ARE QUITE A BIT FURTHER EAST WITH THE LOW
CENTER COMPARED TO PREVIOUS RUNS. IT SLOWLY WOBBLES OFF TO THE EAST
THROUGH TUESDAY NIGHT WITH LIGHT PRECIPITATION IMPACTING OUR AREA ON
THE BACK SIDE OF THE LOW. WITH A MORE EASTERN TRACK...THE BEST
POTENTIAL FOR PRECIPITATION FOR US WILL BE ACROSS OUR EASTERN HALF
MONDAY INTO TUESDAY. COOLER AIR ADVECTING INTO THE AREA BEHIND THE
LOW WILL ALLOW THE RAIN AND SNOW MIX ON MONDAY TO SWITCH ENTIRELY TO
SNOW MONDAY NIGHT. WINDS WILL ALSO PICK UP FROM THE NORTHWEST MONDAY
NIGHT AND TUESDAY AND BECOME QUITE BREEZY. HIGHS ON MONDAY WILL BE
MILD IN THE 30S...AND COOL SLIGHTLY INTO THE UPPER 20S TO MID 30S ON
TUESDAY.

STRATUS CLOUDS STICK AROUND THE REGION WEDNESDAY WITH ANOTHER
POSSIBLE WEAK WAVE DIVING ALONG THE UPPER LEVEL NORTHWEST FLOW.
SLIGHT CHANCE OF LIGHT SNOW WILL ACCOMPANY THIS WAVE ACROSS OUR
NORTHEASTERN HALF. COOLER TEMPERATURES FILTER BACK INTO THE REGION
MID WEEK DROPPING READINGS BACK BELOW NORMAL.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1040 PM CST THU DEC 18 2014

CLOUDS WILL AGAIN STRUGGLE TO MOVE OUT OF THE AREA INTO FRIDAY.
LATEST RAP/NAM CONTINUE TO HOLD SUB 2K FT CEILINGS IN THE FSD/SUX
TERMINALS WELL INTO FRIDAY. FURTHER WEST...A BIT MORE QUESTIONS
EXIST AS THE EDGE OF STRATUS MAY APPROACH HON BY DAYBREAK. MORE
CONCERNING IS THE POTENTIAL FOR FOG AND VLIFR STRATUS TO DEVELOP
ON THE EDGE OF THE THICKER CLOUD DECK AND MOVE INTO HON FOR MUCH
OF THE MORNING.

WILL ADVERTISE NO IMPROVEMENT FOR THE SECOND HALF OF THE TAF
GIVEN WEAK FLOW AND LINGERING MOISTURE.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

UPDATE...
SHORT TERM...CHENARD
LONG TERM...
AVIATION...DUX



AREA FORECAST DISCUSSION

NWS AMARILLO TX

 1104 PM CST THU DEC 18 2014

.AVIATION...
FOR THE 06Z TAFS...MVFR TO IFR CEILINGS ACROSS THE OKLAHOMA AND
TEXAS PANHANDLES ARE EXPECTED TO REMAIN THROUGH MUCH OF FRIDAY
MORNING. HOWEVER....FOG HAS BEEN SLOW TO DEVELOP. HAVE KEPT MENTION
OF IFR FOG IN TAF SITES THOUGH CONFIDENCE IS WANING THAT VISIBILITIES
WILL DROP THAT LOW. IFR TO MVFR STRATUS DECK WILL REMAIN INTO THE
AFTERNOON BEFORE SLOWLY SCATTERING OUT MID-LATE DAY. CONFIDENCE IS
NOT HIGH ENOUGH TO ADD IN PRECIPITATION AT THIS TIME...AND SHOULD
MAINLY BE CONFINED EAST OF THE TAF SITES TODAY.

ELSENHEIMER

&&

.PREV DISCUSSION... /ISSUED 248 PM CST THU DEC 18 2014/

DISCUSSION...

PRIMARY WEATHER IMPACTS DURING THE NEXT SEVEN DAYS WILL BE IN THE
SHORT TERM WITH PRECIPITATION CHANCES TONIGHT AND POTENTIAL FOR FOG
ONCE AGAIN. MAIN ADJUSTMENT TO THE FORECAST WAS TO TRY AND BE MORE
DETERMINISTIC WITH PRECIPITATION TYPE OVERNIGHT ALTHOUGH THAT
REMAINS A CHALLENGE GIVEN MARGINAL THERMAL PROFILES FOR FROZEN
PRECIPITATION IN MODEL FORECAST SOUNDINGS. INITIAL CONCERNS ARE FOG
POTENTIAL LATER TONIGHT AS LOW LEVEL FLOW BECOMES MORE EASTERLY AND
STRENGTHENS. MOISTURE OVER SOUTHWEST OKLAHOMA AND WESTERN NORTH
TEXAS WILL ADVECT WESTWARD AND UPSLOPE. HAVE INCLUDED AREAS OF FOG
IN THE GRIDS. LOCALLY DENSE FOG WILL AGAIN BE POSSIBLE.

WV LOOP AND 500 MB RAP ANALYSIS CLEARLY SHOWED A SHORTWAVE TROUGH
OVER EASTERN ARIZONA MOVING EASTWARD. SHORT TERM MODELS ARE IN GOOD
AGREEMENT ON THE TIMING AND STRENGTH OF THIS WAVE AS IT MOVES TOWARD
WEST TEXAS TONIGHT AND CROSSES THE REGION TOMORROW MORNING. THE
PERIOD OF BEST OMEGA/SATURATION IN THE DEDRITIC GROWTH ZONE WILL BE
AFTER ABOUT 03Z IN THE WEST SPREADING EASTWARD OVERNIGHT AND LASTING
THROUGH ABOUT 15Z IN THE EAST. JUST BELOW THE DGZ IS A LAYER OF DRY
AIR THAT WILL TAKE SOME TIME TO SATURATE THUS DELAYING THE ONSET OF
PRECIPITATION UNTIL CLOSER TO MIDNIGHT IN THE WEST/CENTRAL AND AFTER
MIDNIGHT IN THE EAST. THE BIGGEST CHALLENGE FOR CONVEYING SENSIBLE
WEATHER IN THIS FORECAST WILL BE THE TEMPERATURE PROFILE. AT LEAST
SHORT RANGE MODELS AGREES FAIRLY WELL. THE DEPTH OF THE ABOVE
FREEZING WET BULB TEMPERATURES IS SUFFICIENT FOR ALL RAIN ACROSS
MOST OF THE AREA...ESPECIALLY THE FAR SOUTHEAST. HAVE TRENDED
PRECIPITATION TYPE TO MORE RAIN AS A RESULT. INCREASED QPF SLIGHTLY
IN THE FAR SOUTHEAST.

QUITE A BIT OF UNCERTAINTY DEVELOPS BY EARLY NEXT WEEK AND CONTINUES
THROUGHOUT THE EXTENDED PERIOD. VERY POWERFUL PACIFIC JET NOSES INTO
THE CENTRAL ROCKIES BY MONDAY EAST OF A SIGNIFICANT MEAN RIDGE OVER
THE EASTERN PACIFIC. A VERY STRONG TROUGH HAS BEEN SHOWN TO DEVELOP
OVER THE EASTERN UNITED STATES. THIS SHOULD HAPPEN BY AROUND
CHRISTMAS EVE OR CHRISTMAS DAY BUT MEDIUM RANGE MODELS STRUGGLE WITH
HOW IT EVOLVES EARLY/MID WEEK ONCE PACIFIC JET MOVES INTO THE
CENTRAL CONUS. NEW 12Z EMCWF IS QUICKER WITH DEVELOPING A CLOSED LOW
WHILE THE GFS IS MORE PRONOUNCED WITH INDIVIDUAL SHORTWAVES
TRAVERSING THE DEEPENING UPPER TROUGH. THE GFS BECOMES DEEPER BY
WEDNESDAY WITH MORE SUBSTANTIAL HEIGHT RISES ON ITS WEST SIDE OVER
THE PLAINS. EXACT IMPLICATIONS FOR US ARE UNCLEAR. WILL NEED TO
WATCH THE POTENTIAL FOR A DOWNSLOPING WARMING/WIND EVENT ON MONDAY.
GFS/MEX DEPICT THIS NOW. ECMWF IS MORE EXPANSIVE WITH HEIGHT FALLS
OVER THE CENTRAL CONUS GIVEN ITS MORE CONSOLIDATED/SPRAWLING
SOLUTION WITH LESS DISTINCT SHORTWAVES EMBEDDED WITHIN. GFS
SOUNDINGS SHOW DEEP MIXING INTO AN AREA OF STRONG FLOW ALOFT WHICH
RAISES SOME CONCERN OF NEAR ADVISORY CRITERIA WINDS IF THIS SOLUTION
VERIFIES. OTHERWISE DID NOT DEVIATE FROM MEDIUM RANGE CONSENSUS. ANY
PRECIPITATION IN THE EXTENDED SHOULD BE INSIGNIFICANT...AND
DIFFICULT TO TIME GIVEN MODEL DIFFERENCES.

BRB

PREV DISCUSSION... /ISSUED 1142 AM CST THU DEC 18 2014/

AVIATION...
FOR THE 18Z TAFS...THE MAIN WEATHER ELEMENTS FOR THIS FCST CYCLE WILL
BE LOW CLOUDS AND EPISODES OF FOG. FOG IS SLOWLY ERODING AT THE TAF
SITES AND SHOULD CONTINUE TO DO SO EARLY THIS AFTERNOON. IFR CIGS
WILL GRADUALY AND TEMPORARILY LIFT INTO THE MVFR CATEGORY AS WELL.
EXPECT THE RETURN OF IFR CIGS AND AREAS OF FOG AGAIN LATE TONIGHT
INTO FRIDAY MORNING. A FAST MOVING UPPER LEVEL STORM SYSTEM WILL
GRAZE THE REGION TONIGHT AND EARLY FRIDAY...AND MAY BRING SOME
SPRINKLES...LIGHT RAIN SHOWERS...FLURRIES...OR VERY LIGHT SNOW.
HOWEVER...THE CHANCE OF PRECIPITATION IS NOT VERY HIGH...SO HAVE
OPTED TO OMIT FROM THE TERMINAL FCSTS AT THIS TIME.

ANDRADE

&&

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.

&&

$$

18/09





AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 333 AM CST FRI DEC 19 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CST FRI DEC 19 2014

THE MAIN FORECAST CHALLENGE INTO TONIGHT IS WITH THE LOW LEVEL
MOISTURE AND WHETHER IT WILL BE ENOUGH TO PRODUCE SOME FREEZING
DRIZZLE OR FLURRIES.

CURRENTLY...A BAND OF 1-2KFT STRATUS THAT EXTENDS FROM NORTHWEST
WISCONSIN DOWN THROUGH SOUTHERN WISCONSIN HAS BEEN PRODUCING SOME
FLURRIES DUE TO SOME WEAK LIFT ASSOCIATED WITH A COLD FRONT THAT
EXTENDS FROM SOUTHERN MICHIGAN WEST-NORTHWEST INTO WESTERN
WISCONSIN. THIS FEATURE WILL PULL EASTWARD THIS MORNING/AFTERNOON
AND SHOULD TAKE THESE FLURRIES EAST AS WELL. TO THE SOUTHWEST
TOWARD DES MOINES...ANOTHER BAND OF LOW LEVEL MOISTURE ASSOCIATED
WITH SOME RETURN SOUTHERLY FLOW/WARM AIR ADVECTION HAS FORMED SOME
FREEZING DRIZZLE AND FLURRIES IN THAT REGION. THE QUESTION FOR
TODAY/TONIGHT IS WHETHER THAT FREEZING DRIZZLE/FLURRIES HOLDS
TOGETHER.

19.00Z NAM/GFS AND 19.06Z RAP SOUNDINGS CERTAINLY SHOW THE SURFACE
TO 800MB LAYER MOISTENING UP THROUGH TONIGHT...ITS JUST A MATTER
OF WHETHER THERE IS ANY LIFT THERE. GIVEN THAT THERE CURRENTLY IS
SOME PRECIPITATION OCCURRING UPSTREAM...THERE DOES APPEAR TO BE
ENOUGH LIFT AND HAVE GONE AHEAD AND ADDED A MENTION OF SOME
PATCHY FREEZING DRIZZLE IN FOR TODAY IN SE MN/NE IA WITH IT
SPREADING EASTWARD OVERNIGHT AS THE MOISTURE SHIFTS EAST. DMX HAS
REPORTED SOME FLURRIES OCCURRING AS WELL AT THE MOMENT MEANING
THAT THERE IS SOME ICE BEING INTRODUCED IN THE LOW LEVELS THOUGH
MOST OF THE FORECAST SOUNDINGS SHOW THAT SATURATED LAYER BEING TOO
WARM TONIGHT TO PRODUCE ANY FLURRIES LOCALLY. NOT SURE WHETHER
THIS FREEZING DRIZZLE IS GOING TO BE ADVISORY WORTHY GIVEN THAT
THERE IS NOT MUCH FOCUS FOR LOW LEVEL LIFT...BUT CONDITIONS WILL
HAVE TO BE MONITORED SINCE AIR/ROAD TEMPERATURES WILL BE BELOW
FREEZING.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 333 AM CST FRI DEC 19 2014

THE PATTERN BECOMES MORE ACTIVE GOING INTO THE LATER PORTION OF
THE WEEKEND ON INTO EARLY NEXT WEEK AS A SERIES OF MID LEVEL SHORT
WAVE TROUGHS PROPAGATE ON THROUGH. THE NEXT DECENT CHANCE FOR
PRECIPITATION APPEARS TO COME IN ON SUNDAY AS LOW LEVEL WARM AIR
ADVECTION WILL COMBING WITH SOME WEAK 700MB TROUGHING TO DEVELOP
SOME PRECIPITATION. PRECIPITATION TYPE IS TRICKY WITH THIS SYSTEM
AS THERE IS A WEAK WARM LAYER THAT REACHES +1 TO +2C AND WOULD
MELT SOME OF THE SNOW THAT FALLS THROUGH IT. THERE ALSO APPEARS
TO BE A DRY LAYER BETWEEN THE 700MB MOISTURE AND SURFACE/LOW LEVEL
MOISTURE WHICH BRINGS INTO QUESTION HOW DEEP THE LIFT REALLY WILL
BE. SURFACE TEMPERATURES WILL ALSO BE CLIMBING TOWARD AND ABOVE
FREEZING WHICH COMPLICATES HOW MUCH SNOW COULD ACCUMULATE. KEPT
SNOW ACCUMULATIONS ON THE LOW SIDE...HALF INCH OR LESS...GIVEN ALL
OF THE QUESTIONS WITH THIS ROUND OF PRECIP.

A DEEPER TROUGH DEVELOPS ACROSS THE DAKOTAS SUNDAY NIGHT INTO
TUESDAY AND WILL BRING A MORE WIDESPREAD SHOT OF
PRECIPITATION...MAINLY RAIN BEFORE CHANGING OVER TO SNOW ON THE
BACKSIDE TUESDAY. THE 19.00Z GFS/ECMWF ARE IN DECENT AGREEMENT
WITH THIS SYSTEM IN REGARD TO TIMING BUT ARE DIFFERENT WITH THEIR
PROGRESSION OF THE SURFACE LOW WITH THE GFS DIGGING DEEPER EARLIER
WITH THE ECMWF KEEPING PRECIPITATION AROUND A TAD LONGER. BOTH
MODELS HAVE THE SNOW OFF TO THE EAST BY CHRISTMAS DAY WITH JUST
SOME WEST TO NORTHWEST WINDS IN THE WAKE OF THE SYSTEM.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1026 PM CST THU DEC 18 2014

SOME CHANGES HAVE BEEN MADE TO THE PREVIOUS AVIATION FORECAST...
WHICH BEGUN ON A 0130Z AMENDMENT TO RST. MVFR STRATUS STILL
PERSISTS OVER THE TAF SITES. HOWEVER...A WEDGE OF DRY AIR BELOW AN
ALTOSTRATUS DECK HAS MADE ITS WAY FROM I-35 TOWARDS RST. RST
SHOULD GO VFR FOR THE START OF THE TAF PERIOD AS A SOUTHWEST WIND
AT THE HEIGHT OF THE CLOUDS PUSHES THE DRY AIR EASTWARD. IN
FACT...THIS DRYING COULD MAKE IT ALL THE WAY TO LSE LATER IN THE
MORNING...BETWEEN 15-19Z TO ALLOW FOR TEMPORARY SCATTERING OUT
THERE. LATE IN THE AFTERNOON...AROUND 20Z...MVFR STRATUS OVER
WESTERN IA AND MN LOOKS TO MOVE INTO RST. MEANWHILE...LIGHT FLOW
SHOULD ALLOW MVFR STRATUS TO REASSERT ITSELF AT LSE. ANTICIPATING
THEN CONDITIONS TO STAY MVFR INTO THE EVENING AS THE TWO STRATUS
DECKS MERGE UP.


&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&

$$

SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...AJ





AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 552 AM CST FRI DEC 19 2014

.SHORT TERM...
259 AM CST

THROUGH SUNDAY...

THE MAIN CONCERNS DURING THE SHORT TERM WILL BE SOME PERIODIC
CHANCES OF VERY LIGHT SNOW OR DRIZZLE THROUGH THE WEEKEND AS SEVERAL
WEAK...AND FAST MOVING MID LEVEL DISTURBANCES SHIFT ACROSS THE AREA.

SURFACE HIGH PRESSURE IS CENTERED ACROSS MUCH OF THE MID AND UPPER
MISSISSIPPI RIVER VALLEY EARLY THIS MORNING. THIS FEATURE IS EXPECTED
TO REMAIN IN CONTROL ACROSS NORTHERN ILLINOIS DURING THE DAY TODAY.
OVERALL...WHICH WILL RESULT IN A VERY LIGHT AND VARIABLE WIND
FIELD ACROSS THE AREA TODAY. AN AREA OF LAKE EFFECT FLURRIES
CONTINUES ACROSS PORTIONS OF THE CHICAGO AREA...AND INTO
NORTHWESTERN INDIANA NEAR LAKE MICHIGAN. MODEL SOUNDINGS INDICATE
JUST DEEP ENOUGH INVERSION HEIGHTS TO SUPPORT ICE IN THE
CLOUDS...AND GIVEN MDW HAS BEEN REPORTING ONLY -SN FOR MOST OF THE
NIGHT IT APPEARS THE THREAT OF FREEZING DRIZZLE WILL BE LOW. ALL
OF THIS ACTIVITY SHOULD WANE ACROSS THE AREA DURING THE MORNING AS
THE WIND FIELD CONTINUES TO WEAKEN OVER SOUTH LAKE MICHIGAN IN
RESPONSE TO THE APPROACHING SURFACE RIDGE OF HIGH PRESSURE.

SURFACE WINDS WILL BEGIN TO SHIFT OUT OF THE SOUTH BY EARLY SATURDAY
MORNING AS THIS SURFACE HIGH BEGINS TO SHIFT EAST OF THE REGION. AS
THIS OCCURS...GUIDANCE IS INSISTENT WITH BRINGING A WEAK UPPER
DISTURBANCE ACROSS NORTHERN ILLINOIS SATURDAY MORNING. THIS WEAK
WAVE IS NOTED IN THE WATER VAPOR IMAGERY CURRENTLY ACROSS
SOUTHEASTERN ALBERTA. MOISTURE APPEARS TO REMAIN LIMITED WITH THIS
WAVE. HOWEVER...I THINK THIS WAVE...AND SOME WEAK ISENTROPIC ASCENT
COULD SQUEEZE OUT A FEW FLURRIES SATURDAY MORNING...SO I HAVE
INCLUDED A SLIGHT CHANCE FOR SUCH IN THE FORECAST.

WARM AIR ADVECTION/ISENTROPIC ASCENT WILL CONTINUE TO INCREASE
ACROSS MUCH OF THE MIDWEST AND GREAT LAKES REGION INTO SUNDAY IN
RESPONSE TO AN INCREASING SOUTHERLY WIND FIELD AHEAD OF A STORM
SYSTEM...WHICH IS EXPECTED TO DEVELOP ACROSS THE PLAINS. THIS COULD
AGAIN RESULT IN A PERIOD OF LIGHT PRECIP ACROSS MAINLY FAR NORTHERN
ILLINOIS VERY LATE SATURDAY NIGHT AND INTO SUNDAY.
OVERALL...CONFIDENCE IS LOW AS TO HOW FAR SOUTH THIS LIGHT PRECIP
WILL BE ABLE TO DEVELOP...BUT GIVEN THE POTENTIAL THAT IF THIS
PRECIP DOES DEVELOP AS FAR SOUTH AS NORTHERN ILLINOIS...THERE COULD
BE A PERIOD OF FREEZING DRIZZLE INTO EARLY SUNDAY MORNING BEFORE
TEMPERATURES JUMP ABOVE FREEZING...I HAVE OPTED TO INCLUDE A SLIGHT
MENTION LATE SATURDAY NIGHT INTO EARLY SUNDAY...MAINLY FOR AREAS
NORTH OF INTERSTATE 90.

KJB

&&

.LONG TERM...
259 AM CST

SUNDAY NIGHT THROUGH THURSDAY...

THE LONG TERM PERIOD WILL BE A PERIOD OF A SIGNIFICANT WEATHER
PATTERN SHIFT ACROSS NORTH AMERICA AND AS SUCH...IT APPEARS LIKELY
THAT THE CENTRAL CONUS WILL BECOME MUCH MORE ACTIVE INTO THE
HOLIDAY WEEK. THE MAIN CONCERNS LOCALLY WITH THIS PATTERN
SHIFT...WILL BE PRECIP TYPES...AND THE ACTUAL EVOLUTION
OF...POTENTIALLY A SIGNIFICANT STORM SYSTEM ACROSS PORTIONS OF THE
GREAT LAKES REGION CHRISTMAS EVE.

UNFORTUNATELY...THE DETAILS OF THIS STORM SYSTEM THIS FAR OUT ARE
STILL LARGELY UNCERTAIN...AS LARGE SCALE PATTERN SHIFTS SUCH AS THIS
TYPICAL RESULT IN LOWER PREDICTABILITY...ESPECIALLY WITH REGARDS TO
THE TRACK AND ACTUAL STRENGTH OF A DEVELOPING STORM SYSTEM. WHAT
APPEARS TO BE LIKELY...HOWEVER...IS FOR A PERIOD OF RAIN ACROSS THE
AREA LATE MONDAY AND MONDAY NIGHT AS WHAT APPEARS TO BE THE INITIAL
STORM SYSTEM...BEGINS TO SHIFT A WARM FRONT ACROSS NORTHERN
ILLINOIS. GIVEN THE WARM SECTOR PLACEMENT OF MY AREA...PRECIP TYPE
LOOKS TO BE LIQUID...WITH SURFACE TEMPERATURES LIKELY TO REMAIN
ABOVE FREEZING MONDAY NIGHT WITH CONTINUED SOUTHERN FLOW.

THE MAIN UNCERTAINTIES COME INTO PLAY BY CHRISTMAS EVE...AS MODEL
GUIDANCE CONTINUES TO ADVERTISE A SIGNIFICANT AMPLIFICATION TO THE
UPPER LEVEL PATTERN ACROSS THE EASTERN PACIFIC AND NORTH AMERICA. A
STRONG PACIFIC JET (NEAR 40 DEGREES N)...INITIALIZED AT OVER 180 KT
IN THIS EVENINGS MODEL OUTPUT IS FORECAST TO RESULT IN THE BUILDING
OF A POTENT UPPER RIDGE JUST OFF THE CALIFORNIA COAST BY EARLY NEXT
WEEK. TELECONNECTIONS RELATED TO SUCH PATTERN SHIFT CERTAINLY SUPPORT
THE DIGGING OF A SIGNIFICANT TROUGH...AND A GOOD POSSIBILITY OF AN
STORM SYSTEM ACROSS THE CENTRAL CONUS DURING THE UPCOMING HOLIDAY
WEEK. HOWEVER...AS PREVIOUSLY MENTIONED CONFIDENCE IS LOW WITH THE
DETAILS OF HOW AND WHERE EXACTLY THIS STORM MAY TRACK. THIS IS A
PERIOD WORTH WATCHING THOUGH...AS AT LEAST SOME SNOW AND POSSIBLY
STRONG NORTHWEST WINDS COULD BE IN STORE.

KJB

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 12Z...

* A FEW LINGERING FLURRIES EARLY THIS AM...MAINLY MDW AND
  SOUTHEAST.

* MVFR CEILINGS TO PERSIST MUCH OF PERIOD...LIFTING NEAR VFR OR
  POSSIBLY SCATTERING OUT FOR A TIME MID-MORNING THROUGH THIS
  AFTERNOON.

* LIGHT WINDS 5 KT OR LESS. STARTING WEST-NORTHWEST EARLY THIS
  MORNING...LIKELY VARIABLE OR CALM LATER TODAY/THIS EVENING.

RATZER

//DISCUSSION...UPDATED 12Z...

DIFFUSE SURFACE HIGH PRESSURE RIDGE OVER THE AREA WILL DRIFT VERY
SLOWLY TO THE EAST TODAY AND TONIGHT...RESULTING IN LIGHT WINDS
AND PERSISTENT MVFR CLOUD LAYER TRAPPED BENEATH SHALLOW INVERSION.
AREA OF CLEARING SOUTH OF THE TERMINALS FROM MLI-DNV-IND NOT
MOVING MUCH...THOUGH THERE HAS BEEN SOME EROSION OF CEILINGS
SOUTHWEST OF CHICAGO. FORECAST SOUNDINGS GENERALLY POOR AT
HANDLING MOISTURE BENEATH THIS SHALLOW INVERSION...BUT THERE IS
SOME INDICATION OF SOME RAISING OF CEILINGS OR EVEN SCATTERING
OUT FOR A TIME LATER THIS MORNING INTO THIS AFTERNOON. MVFR
CEILINGS LIKELY TO REDEVELOP AND/OR LOWER LATER TONIGHT HOWEVER AS
SURFACE RIDGE PASSES AND LIGHT SOUTH-SOUTHWEST FLOW DEVELOPS AND
LEADS TO MOISTENING OF LOW LEVELS.

AS FOR WINDS...LIGHT NORTHERLY SFC FLOW AROUND 5 KT EXPECTED TO
BECOME VARIABLE AT LESS THAN 5 KT AS SURFACE RIDGE MOVES THROUGH
TODAY AND THIS EVENING. WINDS THEN BECOME SOUTH-SOUTHWEST AROUND 5
KT TONIGHT INTO SATURDAY MORNING.

RATZER


//ORD AND MDW CONFIDENCE...UPDATED 12Z...

* MEDIUM-LOW IN CEILING HEIGHTS...THOUGH MEDIUM IN GENERAL TREND.

* HIGH IN LIGHT WIND TRENDS.

RATZER

//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...

SATURDAY NIGHT...MVFR LIKELY. LIGHT SOUTH WINDS.

SUNDAY...SLGT CHANCE FLURRIES/FREEZING DRIZZLE EARLY. MVFR LIKELY.
SOUTH-SOUTHEAST WINDS.

MONDAY AND TUESDAY...CHANCE OF RAIN...ESPECIALLY MONDAY NIGHT. MVFR
LIKELY. SOUTHEAST WINDS MONDAY BECOMING SOUTHWEST TUESDAY.

WEDNESDAY...CHANCE OF SNOW. MVFR POSSIBLE. GUSTY WEST WINDS.

THURSDAY...DRY. VFR.

RATZER

&&

.MARINE...
156 AM CST

MAIN MARINE CONCERNS THIS MORNING ARE A PERIOD OF STRENGTHENING
SOUTH-SOUTHEAST WINDS LATE SUNDAY THROUGH MONDAY NIGHT...THEN THE
POTENTIAL FOR WEST GALES LATE WEDNESDAY INTO THURSDAY.

FAIRLY QUIET STRETCH OF WEATHER ACROSS LAKE MICHIGAN TODAY THROUGH
SATURDAY AS A LARGE AREA OF WEAK HIGH PRESSURE DRIFTS SLOWLY EAST
ACROSS THE REGION. LIGHT NORTH WINDS TODAY WILL BECOME SOMEWHAT
LIGHT/VARIABLE...BEFORE BECOMING LIGHT SOUTH ON SATURDAY AS THE
SURFACE RIDGE AXIS PASSES TO THE EAST. SOUTHERLY WINDS WILL THEN
BEGIN TO INCREASE SATURDAY NIGHT AND MORE SO SUNDAY...AS LOW
PRESSURE DEVELOPS IN THE LEE OF THE NORTHERN ROCKIES AND THE
GRADIENT BEGINS TO TIGHTEN ACROSS THE PLAINS AND UPPER MIDWEST.
MEDIUM RANGE FORECAST MODELS ARE IN GENERAL AGREEMENT IN DEVELOPING
A SUB-1000 MB SURFACE LOW ACROSS IOWA OR SOUTHERN MINNESOTA BY
MIDDAY MONDAY...WHICH WOULD LEAD TO SOUTH-SOUTHEAST WINDS IN THE
20-25 KT RANGE THROUGH MONDAY BEFORE OCCLUDING AND WEAKENING AS THE
LOW MOVES ACROSS WISCONSIN AND LAKE MICHIGAN ON TUESDAY.

HOWEVER...VARIOUS MODEL AND MODEL ENSEMBLE MEMBERS THEN DEVELOP A
SECOND LOW SOUTH OF THE LAKES ALONG THE TRAILING COLD FRONT TUESDAY
NIGHT...WHICH WOULD LIFT NORTH AND COMBINE WITH THE FILLING GREAT
LAKES LOW...DEEPENING RAPIDLY WEDNESDAY AND WEDNESDAY NIGHT OVER THE
EASTERN LAKES. THIS SCENARIO WOULD LEAD TO QUICKLY INCREASING
WESTERLY WINDS ACROSS LAKE MICHIGAN...QUITE POSSIBLY WEST GALES...
LATE WEDNESDAY INTO THURSDAY/CHRISTMAS DAY AS THE LOW PULLS AWAY TO
THE NORTHEAST.

RATZER

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$

VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
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WWW.YOUTUBE.COM/NWSCHICAGO





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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
537 AM CST Fri Dec 19 2014

.SHORT TERM...(Today)
ISSUED AT 459 AM CST FRI DEC 19 2014

High pressure is expected to hold over central Illinois through
today with the next southern stream shortwave, currently over south
central Texas early this morning, forecast to track well south of
our area. 2am satellite data and surface observations showing an
area of clear skies extending from just northwest of Peoria
southeast thru Champaign and Decatur. Short range models suggest
this area will gradually fill back in with clouds as the day wears
on. Forecast soundings from the HRRR and Rapid Refresh models also
support this idea thru the day with the last few satellite frames
off the IR loop indicating the clouds over far west central IL were
starting to shift more to the east. Forecast soundings across
central IL today support afternoon temperatures in the low to mid
30s with another day with very little wind, something that is a bit
on the rare side for December across our area.


&&

.LONG TERM...(Tonight through Thursday)
ISSUED AT 459 AM CST FRI DEC 19 2014

Main focus remains with active pattern setting up for the upcoming
holiday week.

Powerful jet of 120-160 knots at 300 mb will be coming into the
Pacific Northwest later this weekend before diving toward the
southern Plains, helping to carve out a deep trough over the central
U.S. The GFS and ECMWF models are in good agreement with development
of a closed low over eastern South Dakota by midday Monday, with
some minor disagreements as to the amount of wobbling of this low as
it drifts toward the east. The ECMWF brings the center as far south
as Springfield by Wednesday morning, while the GFS and Canadian
models are centered across Wisconsin.

Precipitation shield with this system expected to start spreading
into the Illinois River valley by late Monday morning, then eastward
across the state during the day. The GFS is more prominent with a
dry slot punching in already by late evening, while the ECMWF
lingers the rain into Tuesday morning. Leaned more towards the
slower ECMWF solution and increased rain chances to around 60%
Monday night north of I-74 and east of I-57. Forecast soundings are
well above freezing up to around 850 mb, so have removed any mixed
precip wording for Monday night. Some mixture possible northwest of
the Illinois River on Tuesday, although a loss of ice crystals aloft
with the dry slot may mitigate this.

As we head toward Christmas Eve, amount of wrap-around precipitation
is a concern. The ECMWF rapidly intensifies the surface cyclone to
our east, with central pressure down to around 978 mb midday near
Cleveland. This solution brings periodic snow showers southeast into
our area in the strong northwest flow. The much weaker GFS has some
flurries lingering through the day, with less windy conditions. Have
kept precipitation chances across the east during the day on the
edge of the ECMWF`s dry slot, but kept only slight chances elsewhere
for now. Snowfall amounts still appear to be on the light side, but
holiday travel will still not be pleasant with the snow and the
winds. Christmas Day itself appears dry.


&&

.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 525 AM CST FRI DEC 19 2014

High pressure centered from northeast Iowa southeast thru central
Illinois has helped to scour out some of the MVFR clouds that
have dominated our area over the past 24 hours, especially along
the ridge axis early this morning. Satellite data indicates the
clear area extended from Moline southeast thru Peoria, Bloomington
and Champaign with MVFR cigs to the north and south. Forecast
soundings continue to suggest areas that were experiencing the
clear skies this morning should see the low VFR and even some MVFR
cigs move back in by later this morning into the afternoon hours.
Confidence on timing and extent of the lower VFR and MVFR cigs
across the area today is rather low, so will trend with more
clouds across the north and east by later this morning into the
afternoon hours but keep it mostly low VFR at this time. Surface
winds will once again be a non- factor today as our area will be
under the high pressure system so will continue with a light and
variable wind over most of the area into tonight.

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Smith
LONG TERM...Geelhart
AVIATION...Smith





AREA FORECAST DISCUSSION

NWS GOODLAND KS

 428 AM MST FRI DEC 19 2014

.SHORT TERM...(THIS MORNING THROUGH SUNDAY NIGHT)
ISSUED AT 233 AM MST FRI DEC 19 2014

EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW SHORTWAVE
TROUGH OVER OK PANHANDLE WITH SHORTWAVE RIDGE OVER THE TREAT BASIN
BUILDING EAST TOWARDS THE CENTRAL ROCKIES. AT THE SURFACE...LOW
PRESSURE REMAINS IN PLACE FROM THE NORTHERN PLAINS AND ACROSS
EASTERN COLORADO. HIGH PRESSURE IS GENERALLY IN PLACES ACROSS MUCH
OF THE CWA...WITH LOW PRESSURE BEGINNING TO BUILD IN FROM THE WEST.

EARLY THIS MORNING...AXIS OF DENSE FOG DEVELOPED LATE LAST NIGHT
GENERALLY ALONG HWY 25 AND HWY 83 CORRIDOR BEHIND STRATUS DECK TO
THE EAST. WEST OF THIS...BL HAS BEEN TOO DRY FOR DENSE FOG
DEVELOPMENT...THOUGH WITH NEARBY HIGH PRESSURE/LIGHT WINDS/CLEAR
SKIES PATCHY FOG WILL BE POSSIBLE THIS MORNING. RAP/HRRR BOTH HAVE
GOOD REFLECTION OF THE SPOTTY NATURE OF THE FOG OVER OUR CWA...AND
GENERALLY KEEP MAIN AXIS OF DENSE FOG WHERE IT IS...IMPROVING
CONDITIONS AROUND 12-13Z. DUE TO THE LOCALIZED NATURE OF THE
DENSE FOG AND GUIDANCE TRENDING AWAY FROM WIDESPREAD COVERAGE I
DECIDED TO CONTINUE WITH HANDLING THIS EVENT WITH SPS.

TODAY...ANY FOG/STRATUS SHOULD CLEAR BY MIDDAY AS SURFACE LOW SHIFTS
EAST TO THE KS/CO BORDER. THIS WILL SUPPORT TEMPS MODERATING TO THE
40S/NEAR 50 OVER MUCH OF THE CWA (COOLER IN YUMA COUNTY WHERE SNOW
PACK LINGERS).

TONIGHT-WE MAY SEE FOG REDEVELOP ACROSS NORTH CENTRAL KS...WHICH
COULD IMPACT OUR EASTERN CWA. THOUGH NAM/SREF HAVE A PRETTY GOOD
SIGNAL FOR THIS...AS LOW SHIFTS EAST AIR MASS WILL BE CHANGING WITH
LOWER BL MOISTURE PRESENT AND IM NOT AS SURE CURRENT MODEL
COVERAGE/DEPICTION IS REALISTIC. I ADDED PATCHY FREEZING FOG IN OUR
EAST AHEAD OF MAIN SURFACE TROUGH TO COVER POTENTIAL.

SATURDAY-SUNDAY...SHORTWAVE RIDGE WILL TRANSITION EASTWARD ACROSS
THE PLAINS SATURDAY/SATURDAY NIGHT WITH A TROUGH REDEVELOPING OVER
THE NORTHERN PLAINS BY SUNDAY NIGHT. AHEAD OF THIS DEVELOPING UPPER
TROUGH...SURFACE TROUGHING AND INCREASING WAA WILL SUPPORT
INCREASING TEMPS TO WELL ABOVE NORMAL. DEPENDING ON MIXING (WHICH
COULD BE LIMITED BY CLOUDS)...HIGHS BY SUNDAY SHOULD BE IN MIDDLE
50S WITH DECREASING IMPACT FROM SNOW PACK IN THE NORTHWEST AS IT
CONTINUES TO DEGRADE OVER THE NEXT FEW DAYS. I COULD ACTUALLY SEE
SOME LOCATIONS APPROACH THE UPPER 50S SUNDAY BASED ON CURRENT
925/850 MB TEMPS.

SUNDAY NIGHT...LOBES OF MID LEVEL VORTICITY COMBINED WITH INCREASING
FRONTOGENETIC FORCING COULD SUPPORT SEVERAL BANDS OF LIGHT
PRECIPITATION MOVING INTO OUR CWA BY SUNDAY NIGHT. MODELS ARE
SHOWING A GOOD DRY LAYER THAT ANY PRECIP WOULD HAVE TO SATURATE
THROUGH. TEMP PROFILES GENERALLY SUPPORT RAIN...WITH SATURATION TO
WET BULB TEMPS NEAR A RAIN OR RAIN/SNOW MIX LATE SUNDAY NIGHT. DUE
TO UNCERTAINTY OF MEASURABLE DUE TO DRY LAYER AND POSITION OF
THESE BANDS...I KEPT POP MENTION LIMITED TO SLIGHT CHANCE.

.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 233 AM MST FRI DEC 19 2014

AN UPPER LEVEL TROUGH WILL MOVE THROUGH THE CENTRAL PLAINS REGION
MONDAY...BRINGING CHANCES FOR RAIN AND SNOW SHOWERS.  BASED ON THE
LOWER LEVEL TEMPERATURE FIELD...CRITICAL THICKNESSES AND WET BULB
ZERO HEIGHTS...EXPECTING NORTHWEST PORTIONS OF THE FORECAST AREA TO
START AS A RAIN/SNOW MIX.  OTHERWISE...ALL OTHER AREAS WILL RECEIVE
RAIN MONDAY MORNING.  ALTHOUGH THERE IS STRONG NORTHWEST FLOW ALOFT
WITH COOLER TEMPERATURES BEING ADVECTED INTO THE AREA...SURFACE
TEMPERATURES WILL WARM INTO THE MID TO UPPER 40S IN THE AFTERNOON.
THIS SURFACE WARMING WILL ALLOW RAIN TO BE THE PRIMARY PRECIPITATION
TYPE IN THE AFTERNOON.  PRECIPITATION WILL CHANGE BACK TO SNOW AFTER
SUNSET.  ECMWF AND GFS MODELS ARE FORECASTING BETWEEN 1 AND 2 INCHES
OF SNOW...HOWEVER CONFIDENCE IS LOW IN THOSE FORECAST AMOUNTS DUE TO
RUNNING ACCUMULATIONS IN PERIODS OF PHASE CHANGE. THEREFORE...THE
FORECAST REFLECTS TOTAL VALUES LESS THAN AN INCH AT THIS TIME.

A SHORTWAVE RIDGE WILL BUILD INTO THE TRI STATE AREA TUESDAY AND
WEDNESDAY...BRINGING DRY CONDITIONS AND NEAR NORMAL HIGH
TEMPERATURES IN THE LOW TO UPPER 40S.  BLENDED POP FORECAST WAS
HINTING AT PRECIPITATION CHANCES THROUGH THE DAY TUESDAY...BUT
DECIDED TO ELIMINATE POPS DUE TO THE 500 MB AXIS BEING THROUGH THE
FORECAST AREA BY 18Z TUESDAY.

THE NEXT WEATHER SYSTEM TO APPROACH THE REGION WILL COME FROM THE
PACIFIC NORTHWEST CHRISTMAS EVE THROUGH CHRISTMAS DAY.  ALTHOUGH
THIS SYSTEM IS STILL A FEW DAYS OUT...GUIDANCE IS SEEMINGLY SLOWING
THE PROGRESSION OF THE SYSTEM INTO THE AREA TOWARDS A THURSDAY NIGHT
OR FRIDAY ARRIVAL. A GENERAL NORTHWEST FLOW WILL BRING MOISTURE IN
FROM THE PACIFIC NORTHWEST MAINLY ON THE NORTHERN COLD SIDE OF THE
SURFACE LOW...WHICH WILL BRING CHANCES FOR SNOW SHOWERS.  AT THIS
TIME...THINKING A LITTLE OVER AN INCH CAN BE EXPECTED FOR AREAS
NORTH OF INTERSTATE 70.  THIS AMOUNT IS LIKELY TO CHANGE WITH FUTURE
FORECASTS.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 427 AM MST FRI DEC 19 2014

DENSE FREEZING FOG WITH 1/4 SM VIS HAD CONTINUED AT KMCK MOST OF
THE OVERNIGHT PERIOD...WITH RECENT TRENDS THIS HOUR SHOWING SLIGHT
IMPROVEMENT. GUIDANCE INDICATES FOG WILL BEGIN TO ERODE AROUND
SUNRISE...WITH VFR CONDITIONS EXPECTED BY MIDDAY. WESTERLY WINDS
HAVE HELPED KEEP LOW LEVELS MIXED AT KGLD AND VFR CONDITIONS IN
PLACE. IF WINDS WERE TO GO CALM AROUND SUNSET I COULD SEE FOG
DEVELOPING...HOWEVER SHORT RANGE GUIDANCE IS FAVORING VFR AT KGLD
WITH ANY FOG REMAINING OUTSIDE OF THE VICINITY OF THE TERMINAL.
WILL NEED TO MONITOR 12-15Z AS THAT WILL WILL BE WINDOW FOR
POSSIBLE FOG DEVELOPMENT. WINDS WILL REMAIN AROUND 7KT FROM THE
SOUTHWEST FOR MOST OF THE TAF PERIOD AT BOTH TERMINALS.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

$$

SHORT TERM...DR
LONG TERM...MK
AVIATION...DR



AREA FORECAST DISCUSSION

NWS TOPEKA KS

 518 AM CST Fri Dec 19 2014

...AVIATION UPDATE...

.SHORT TERM...(Today and Tonight)
Issued at 246 AM CST FRI DEC 19 2014

08Z water vapor imagery indicated there were a couple waves within a
somewhat slow split flow over the plains. The stronger wave was
lifting through the southern plains with some decent lightning noted
in eastern TX. A second weaker wave was noted over southeastern MT.
At the surface a high pressure system centered over the central and
upper MS river valley was nosing into eastern KS with a ridge axis
bisecting the forecast area.

For today and tonight, the better forcing from the shortwaves looks
to only glance the forecast area. Forecast soundings from the
RAP/NAM/GFS indicated a decent amount of dry air in the mid levels
and prog a westerly wind at 850 and above to continue advecting dry
air in from the west. So with the weak forcing unlikely to overcome
the dry air in mid levels, have maintained a dry forecast through
tonight. Really the main forecast challenge is the boundary layer
moisture and pesky stratus. All the models fall to mix out the low
level inversion and the boundary layer moisture. This seems to make
some since with the expansive stratus deck already in place and snow
cover limiting any insolation to warm surface temps. Therefore have
leaned towards an overcast sky through tonight. Isentropic surfaces
show only weak if any isentropic upglide and appear to focus this
mainly across MO, so concerns for drizzle are minimal today as well.
About the only uncertainty with the forecast is the NAM`s tendency
to over due the impact of the snow cover and keeping the boundary
layer to cool for to long. However with the GFS and RAP showing
similar solutions, think the low clouds scattering out is a low
chance occurrence. Highs today are expected to be in the mid 30s
with no real low level warm air advection and clouds holding on
strong. For tonight have kept skies cloudy, but if for some reason
we were to clear out, fog would become more likely. I don`t have a
lot of confidence in this happening. Nevertheless have added a
mention of patchy fog after midnight due to forecast soundings
showing the potential for some fog, especially across north central
KS. Lows tonight are expected to range from the mid 20 to around 30.

.LONG TERM...(Saturday through Thursday)
Issued at 246 AM CST FRI DEC 19 2014

Patchy fog is expected to linger through mid morning Saturday before
lifting to mostly cloudy stratus. A developing surface trough over
eastern CO will pick up winds around 10 mph, attempting to mix out
the stratus in the lower levels. Best chances for seeing peeks of
sunshine lie across central KS, with much of the CWA remaining
cloudy. Despite the warmer temps from guidance, believe the
lingering snow cover holds highs a few degrees cooler in north
central and far northeast KS where upper 30s are common. Areas with
little to no snow cover may reach the lower to middle 40s. Surface
trough begins to deepen on Sunday in response to the upper shortwave
trough coming onshore from the Pacific NW. Southwesterly winds
increase around 15 mph through the afternoon. A weaker lead trough
progresses over the northern plains Sunday morning, bringing a
chance for light drizzle. Freezing precip should not be a concern as
guidance is trending warmer near 40 degrees for morning lows.
Precip chances increase Sunday evening into Monday as the system
shifts east over the northern plains. Discrepancies remain on
guidance as the latest ECMWF is less amplified and impacting more
of the eastern CWA, similar to the GEM. In addition, the GFS is
more amplified from an upper jet streak rounding the southern edge
of the wave. Given this and the amount of saturation is relative
compared to previous systems, will continue with 30-40 pops until
more consistency is seen between runs. Bulk of the QPF is rain on
Monday as highs peak in the upper 40s. The freezing temps slide in
behind the departing wave where a rain and snow mix is possible
Monday evening. No accumulation is expected at this time.

An anomalous upper ridge builds eastward into the region Tuesday and
Wednesday giving the area a chance to clear out the stratus clouds.
Modified airmass in the wake of the system will only drop highs into
the low 40s for highs and lows in the upper 20s and low 30s. In
terms of Christmas Day, much uncertainty exists with the timing and
track of the next upper trough. Latest runs are trending slower with
the system, GFS being more progressive and impacting mainly north
central areas. Meanwhile the ECMWF is slower and places our area in
the dry slot. While confidence is below average, will maintain
forecast consistency with slight chances for a rain and snow mix.

&&

.AVIATION...(For the 12Z TAFs through 12Z Saturday Morning)
Issued at 518 AM CST FRI DEC 19 2014

Uncertainty hings mainly on what the CIGS will do. Have continued
with the prev forecast idea of CIGS gradually improving above 1
KFT this afternoon. Have timed this with the passage of the
surface ridge axis, thinking southerly winds around 5KT could aid
in boundary layer mixing and cause the CIGS to lift. Since none of
the forecast soundings mix out the low level inversion this
afternoon, think IFR CIGS are likely to return overnight.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Wolters







AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 647 AM EST FRI DEC 19 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM EST FRI DEC 19 2014

A FAIRLY QUIET PATTERN IN THE CENTRAL PART OF THE CONUS...AS THE
SOUTHERN STREAM JET IS SITUATED OVER THE SOUTHERN TIER OF STATES
AND THE SYSTEM THAT BROUGHT SNOW TO THE AREA THIS PAST
TUESDAY/WEDNESDAY IS NOW SPINNING OVER PRINCE EDWARD ISLAND. CLOSER
TO THIS AREA...AN UPPER RIDGE STRETCHES FROM WISCONSIN TO JAMES
BAY...WHILE A UPPER TROUGH IS LOCATED OVER SASKATCHEWAN AND THE
NORTHERN PLAINS. BENEATH THE UPPER RIDGE...1028MB HIGH PRESSURE IS
CENTERED OVER NORTHERN LAKE SUPERIOR WITH A RIDGE STRETCHING SOUTH
THROUGH THE MID MISSISSIPPI VALLEY. THERE IS PLENTY OF DRY AIR ALOFT
ON THE RAP ANALYSIS ASSOCIATED WITH THIS UPPER RIDGE...BUT THE
SUBSIDENCE HAS STRENGTHENED THE INVERSION OVER THE GREAT LAKES AND
UPPER MISSISSIPPI VALLEY REGIONS AND AIDED IN AREAS OF LOW CLOUDS.
THE LARGEST AREA OF LOW CLOUDS COVERS MUCH OF MINNESOTA AND WESTERN
WISCONSIN...WITH THE EASTERN EDGE STRETCHING FROM GRAND MARAIS
MINNESOTA THROUGH IRONWOOD MICHIGAN AND TOWARDS MADISON WISCONSIN.
BUT THERE IS A POCKET OF CLOUDS THAT DEVELOPED OVER SOUTH CENTRAL
LAKE SUPERIOR LATE THIS EVENING (AIDED BY MARGINAL DELTA-T VALUES
FOR LAKE CLOUDS) AND WITH THE LIGHT NORTHERLY FLOW...SHIFTED INTO
THE KEWEENAW AND NORTH CENTRAL U.P.  DEFINITELY HAVE TO GIVE SOME
CREDIT TO THE REGIONAL GEM...WHICH SUPERBLY PICKED UP ON THESE
CLOUDS WITH THE 00Z RUN YESTERDAY. THESE CLOUDS ALLOWED TEMPERATURES
TO QUICKLY RISE AROUND 10 DEGREES AND LOCATIONS UNDER THEM ARE IN
THE MID-UPPER TEENS. ELSEWHERE IN THE U.P. SKIES ARE CLEAR AND WITH
THE LIGHT WINDS...TEMPERATURES HAVE FALLEN INTO THE LOWER SINGLE
DIGITS ABOVE AND BELOW ZERO.

THE UPPER RIDGE AND SURFACE HIGH CURRENTLY OVER THE AREA WILL
SLOWLY SHIFT EAST-SOUTHEAST TODAY AND TONIGHT...ALLOWING THE AREA
TO COME UNDER GREATER INFLUENCE OF THE WEAK UPPER TROUGH. THE LOW
CLOUDS WILL BE THE PRIMARY CONCERN FOR THE FORECAST FOR TODAY. WITH
GENERALLY LIGHT WINDS AND A RELATIVELY LOW SUN ANGLE...GETTING A
HANDLE ON THE LOW CLOUDS OVER THE NORTH CENTRAL AND KEWEENAW IS
DIFFICULT. FOLLOWING 925MB WINDS IN THE MODELS...WOULD EXPECT THEM
TO TRY TO NOSE A LITTLE FARTHER INLAND OVER THE CENTRAL (AND EVEN
THE EASTERN) PART OF THE U.P. TODAY...WHILE THE DEVELOPING LIGHT
SOUTHERLY FLOW WOULD LIKELY PULL DRIER AIR BACK INTO THE KEWEENAW
AND PUSH THOSE CLOUDS NORTH. BUT THAT INCREASING SOUTHERLY FLOW
WILL ALSO PULL THE CLOUDS RIGHT NEAR IRONWOOD INTO THE REST OF
GOGEBIC AND ONTONAGON COUNTIES THROUGH THE DAY TODAY...EVENTUALLY
REACHING IRON/HOUGHTON COUNTIES THIS EVENING AS THE LIMITED MIXING
DECREASES AND THE STRATUS CAN REALLY EXPAND. THESE LOW CLOUDS
(ALONG WITH MID CLOUDS FROM THE WEAK UPPER TROUGH AXIS SHIFTING EAST
INTO MINNESOTA) WILL CONTINUE TO SPREAD ACROSS UPPER MICHIGAN FROM
SOUTHWEST TO NORTHEAST TONIGHT AS SOUTHWESTERLY FLOW GRADUALLY
DEVELOPS.

AS FOR TEMPERATURES...EVEN WITH THE COLD START THIS MORNING IN
SOME LOCATIONS...EXPECT ANOTHER DAY OF HIGHS A LITTLE BIT
ABOVE NORMAL (UPPER 20S TO LOWER 30S). THE LOWS TONIGHT WILL BE
TRICKY...AS THEY DEPEND ON THE LOCATIONS OF THE CLOUD COVER. WHERE
SKIES ARE CLEAR OVER THE CENTRAL AND EAST...WOULD EXPECT ANOTHER
QUICK DROP TO TEMPS IN THE EVENING AND NEARING 0 UNDER LIGHT WINDS.
BUT WHERE THERE ARE CLOUDS...TEMPS WILL STRUGGLE TO FALL INTO THE
MID TEENS. WILL KEEP LOWS UP THE HIGHEST OVER THE FAR WEST...WHERE
THE CLOUDS WILL MOST LIKELY BE LOCATED.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM EST FRI DEC 19 2014

MAIN FCST CONCERNS IN THE MEDIUM/EXTENDED RANGE INCLUDE POPS ON SUN
NGT INTO MON AS A WAA REGIME DEVELOPS IN THE UPR LKS BTWN HI PRES
MOVING INTO NEW ENGLAND AND LO PRES TAKING SHAPE IN THE NRN PLAINS
ASSOCIATED WITH A STRONGER SHRTWV RIDING OVER A RDG ALONG THE W
COAST. THE POTENTIAL FOR A HEAVIER SYNOPTIC THEN LK ENHANCED SN IS
STILL THERE FOR TUE THRU XMAS AS THE DIGGING SHRTWV DEEPENS AN UPR
TROF OVER THE CENTRAL CONUS AND A LO PRES SOMEWHERE IN THE GREAT
LKS. BUT THERE REMAINS SOME INCONSISTENCIES AMONG THE MEDIUM/LONG
RANGE GUIDANCE ON THIS LO AND HOW QUICKLY A SECOND LO WL TAKE
SHAPE...SO CONFIDENCE IS LO ON THE FCST FOR MON THRU XMAS.

SAT/SAT NGT...A SFC HI PRES RDG STRETCHING FM WRN QUEBEC INTO THE
MID MS RIVER VALLEY ON SAT MRNG WILL MOVE SLOWLY TO THE E AND TO
NEAR NEW ENGLAND TO THE OH RIVER VALLEY BY 12Z SUN UNDER LGT W FLOW
ALOFT. A WEAK SHRTWV EMBEDDED IN THIS W FLOW WL BE DRIFTING THRU THE
UPR LKS DURING THIS PERIOD. ALTHOUGH THERE WL BE SOME WAA IN THE SW
FLOW ON THE BACK SIDE OF THE DEPARTING HI AND PVA IN ADVANCE OF THE
SHRTWV...MODELS SHOW ONLY WEAK ISENTROPIC ASCENT/DEEP LYR QVECTOR
CNVGC/UVV IN THE ABSENCE OF SGNFT MSTR INFLOW. SINCE FCST SDNGS
INDICATE LIMITED DEEP SATURATION...WL MAINTAIN GOING DRY FCST AND
MOCLDY SKIES. TEMPS SHOULD RUN ABOVE NORMAL FOR THE SEASON WITH H85
TEMPS NOT FAR FM -5C TO -7C.

SUN/SUN NGT...MOST OF THE MEDIUM RANGE OPERATIONAL MODELS SHOW
ANOTHER MORE COMPACT SHRTWV CROSSING THE UPR LKS ON LATE SUN INTO
EARLY MON ACCOMPANIED BY SOME SHARPER DPVA. IN TANDEM WITH SOME MORE
IMPRESSIVE ISENTROPIC ASCENT IN THE SSW FLOW BTWN THE DEPARTING HI
PRES RDG TO THE E AND FALLING MSLP IN THE NRN PLAINS ASSOCIATED WITH
A STRONGER SHRTWV RIDING THRU THE NRN ROCKIES AND OVER THE UPR RDG
OFF THE W COAST...MODELS DO GENERATE SOME WIDESPREAD ALBEIT LGT PCPN
AT TIMES DURING THIS PERIOD. THE GFS SHOWS A WEAKER SHRTWV/DYNAMIC
FORCING...BUT ENUF ISENTROPIC ASCENT TO GENERATE SOME LGT PCPN AS
WELL. FCST WL SHOW A PERIOD OF UP TO HI CHC POPS TO REFLECT MODEL
DISCREPANCIES ON THE TIMING OF THE STRONGER UVV. SSW FLOW UP THE
LENGTH OF LK MI MAY SUPPORT SOME HIER POPS OVER THE E...BUT MARGINAL
CHILL OF THE AIRMASS FOR LK ENHANCEMENT AND SOME SHEAR SHOULD LIMIT
THE POTENTIAL FOR A SGNFT IMPACT. TEMPS WL REMAIN ABOVE NORMAL...
ESPECIALLY ON SUN NGT WITH CLD COVER AND A STEADY S WIND GREATLY
LIMITING THE DIURNAL TEMP FALL.

MON THRU XMAS DAY...ALTHOUGH THE MEDIUM/LONG RANGE GUIDANCE ARE IN
AGREEMENT AN UPR TROF WL DEEPEN WITH AN H5 LO CLOSING OFF SOMEWHERE
OVER THE CENTRAL CONUS DOWNSTREAM OF THE RDG OVER THE FAR W AND THAT
THE CLOSED LO/UPR TROF WL TAKE ON A NEGATIVE TILT BY LATE TUE/XMAS
EVE...THERE ARE CONSIDERABLE DIFFERENCES ON THE FCST MSLP AND
THERMAL FIELDS. THE 12Z AND 00Z GFS ENSEMBLE SPREAD ON THE FCST LO
POSITION ON TUE/WED WAS QUITE WIDE...REFLECTING THE RATHER POOR
PREDICTABILITY OF THIS PATTERN WITH THE MAIN PLAYERS STILL OUT OVER
THE DATA POOR PACIFIC OCEAN. IN GENERAL...THE GFS IS FARTHER N WITH
THE RESULTING SFC LO AND THUS SHOWS WARMER LLVL TEMPS THAT WOULD BE
SUFFICIENT FOR A GOOD DEAL OF THE PCPN TO FALL AS RA OVER A GOOD
PORTION OF THE CWA. THE 00Z ECWMF ON THE OTHER HAND SHOWS A FARTHER
S TRACK FOR THE SFC LO AND QUICKER REDEVELOPMENT OF A DEEPER SECOND
LO ASSOCIATED WITH THE SHARPLY DIGGING SHRTWV INTO THE TROF THAT ALL
THE MODELS EVENTUALLY LATCH ON TO AS THE MAIN FEATURE. THE 00Z UKMET
IS CLOSER TO THE ECMWF...WHILE THE CNDN IS MORE OF A COMPROMISE.
SINCE BOTH THE GFS/ECWMF HAVE SHOWN CONTINUITY FM PREVIOUS RUNS AND
THERE IS CONSIDERABLE DIFFERENCES...FOLLOWED A MODEL CONSENSUS APRCH
FOR FCST PREPARATION. DID INCREASE POPS ABOVE THE CONSENSUS ON WED/
THU NEAR LK SUP WITH CYC NE UPSLOPE FLOW SHIFTING TO THE NW BY XMAS
TO THE NW OF DEEPENING LO AND DRAWING COLDER AIR INTO THE UPR LKS
THAT WOULD BE SUFFICIENT FOR SOME LK ENHANCEMENT /H85 TEMPS NEAR
-10C ON XMAS/.
&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 646 AM EST FRI DEC 19 2014

TWO AREAS OF MVFR CEILINGS ARE AFFECTING THE TAF SITES THIS MORNING
AND WILL CONTINUE AT TIMES TODAY AND TONIGHT. AT KIWD...THE EDGE OF
LOW END MVFR CEILINGS HAS BEEN HOVERING OVER THE SITE DURING THE
OVERNIGHT HOURS. WITH LOW LEVEL WINDS STARTING TO INCREASE OUT
OF THE SOUTH...WOULD EXPECT THEM TO PUSH INTO THE SITE SHORTLY AND
CONTINUE THROUGH THE REST OF THE DAY AND INTO TONIGHT.

AT KCMX AND KSAW...MVFR STRATUS PUSHED INTO BOTH SITES LATE
YESTERDAY EVENING. WITH WINDS BECOMING LIGHT TODAY...CONFIDENCE IS
LOW ON THE TIMING OF THEM DEPARTING. THINK THEY WILL DEPART FIRST
AT KCMX WITH SOUTHERLY WINDS DEVELOPING EARLIER AND THERE HAVE BEEN
EASTERLY DOWNSLOPE WINDS OFF THE HURON MOUNTAINS LEADING TO SOME
CLEARING OVER THE KEWEENAW BAY. AT KSAW...THE NORTH-NORTHEASTERLY
FLOW WILL PERSIST THROUGH MUCH OF THE MORNING BEFORE BECOMING
VARIABLE. THAT SHOULD KEEP THE LOW CLOUDS IN THROUGH THE
MORNING...BUT THINK THE SHALLOW NATURE OF THE MOISTURE SHOULD ALLOW
THEM TO BREAK UP THIS AFTERNOON EVEN WITH THE LOW SUN ANGLE. ONCE
THE CLOUDS DEPART...EXPECT VFR CONDITIONS UNTIL THE MVFR CLOUDS
ARRIVE AGAIN FROM THE SOUTHWEST LATE THIS EVENING AND INTO THE
OVERNIGHT HOURS.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 345 AM EST FRI DEC 19 2014

EXPECT LIGHT WINDS UNDER 20 KTS ASSOCIATED WITH HI PRES PASSING THRU
THE UPPER LAKES TODAY TO SHIFT TO THE S BUT REMAIN UNDER 20 KTS
UNTIL AT LEAST SUN. THE S WINDS MAY INCREASE UP TO 25 KTS OVER
MAINLY THE E HALF OF THE LAKE LATER SUN INTO MON IN ADVANCE OF AN
APPROACHING LO PRES. AS ANOTHER LO PRES DEVELOPS TO THE S...THE FLOW
WILL TEND TO BACK AND WEAKEN ON TUE. DEPENDING ON HOW QUICKLY THIS
SECOND LO DEVELOPS AND WHERE IT TRACKS...THERE COULD BE A NW GALE
EVENT ON WED OR XMAS DAY.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...SRF
LONG TERM...KC
AVIATION...SRF
MARINE...KC






AREA FORECAST DISCUSSION...UPDATED AVIATION

NWS ST LOUIS MO

 551 AM CST Fri Dec 19 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 300 AM CST Fri Dec 19 2014

A weak ridge of high pressure which extends from the Great Lakes
region south through the Mid-Mississippi Valley is in control of our
weather today.  Soundings are showing plenty of low level moisture
trapped under an inversion at around 850mb.  The vertical structure
of the atmosphere is much like what we had last weekend with the
moisture stratified in the low levels, so I don`t expect much
sunshine for the majority of the area...with the possible exception
of south central and extreme southwest Illinois.  Some drier air is
trying to drift in on weak easterly low level flow.  Vertical cross
sections show intermittent weak upward motion through the day,
primarily over central Missouri, and short term guidance spits out a
hundredth of QPF here and there.  Additionally, the HRRR shows some
weak simulated radar echos over parts of central and southeast
Missouri today, so have added in a little patchy drizzle to the
forecast.

Carney

.LONG TERM:  (Tonight through Thursday)
Issued at 300 AM CST Fri Dec 19 2014

(Tonight - Saturday)

The brunt of a storm system is expected to pass relatively unnoticed
to our south this evening, and if it weren`t for some interaction
with a more northerly component, would probably result in no
precipitation anywhere, but such as it is, some very light snow
looks to be possible early this evening for an area primarily south
of STL metro.  This arrangement should be short-lived, with much of
the mid and upper level moisture quickly being shunted off to the
east, leaving behind extensive low cloud cover.  At this point,
there is good model consensus on a weak WAA, convergence regime
setting up at the low levels that noses into central MO by midnight
tonight and then snaking its way northward towards the UIN area by
Saturday morning.  Have added in patchy drizzle as a result.  For
now, expecting influence of the surface RIDGE to trump this for STL
metro and areas S and E.  Temps will probably not go very far
tonight with clouds hanging tough, although where the surface RIDGE
is dominant, should see a steady but slow drop...but for areas to
the N and W of STL metro where a light S flow will persist, near
steady temps are expected.  Speaking of temps, especially to the N
and W of STL metro where drizzle is expected to develop, readings
will be within a degree or two of the freezing mark and so this will
probably manifest more as patchy FZDZ for areas in northeast MO and
west-central IL.  Prefer the lower MOS temps for Saturday maxes
given cloud cover expected, but they should still rebound into the
upper 30s and low 40s.

(Sunday - Wednesday)

A rather deep upper level TROF is expected to develop later on
Sunday over the central CONUS and then take a good part of the week
before finally shifting east.  Maintained the highest PoPs for
Monday thru Tuesday, where there is good model consensus on when the
TROF will be close enough, yet its axis still just upstream...and
then reduce to slight chances by Wednesday when the TROF axis by
this time will have shifted to the east.

While much of the precipitation will be just rain, especially on the
front-end, enough cold air starts working in on Tuesday, especially
aloft, that will allow the atmosphere to sustain a changeover to
snow.  The only limiting factor at this point will be surface and/or
boundary layer temps that will ultimately determine the rain vs.
snow question.  GFS and EC MOS surface temps suggest this will not
happen for most locales until late in the day on Tuesday with snow
then expected as the dominant p-type from that point on.  This will
also be when the upper TROF axis will be crossing thru, and so what
is left will probably not be much, but perhaps light snow accums
will be possible Tuesday night and early Wednesday.  This will be
our only realistic chance at a white Christmas, and something to
watch, as a deeper system that digs a bit more south would up the
potential.

(Christmas)

Models have been advertising for several days now a transitional
period this day which should give us a net result of quiet wx with
near seasonal temps.  Nothing has changed with the current model
runs so will let it stand.

TES

&&

.AVIATION:  (For the 12z TAFs through 12z Saturday Morning)
Issued at 538 AM CST Fri Dec 19 2014

Expect persistent ceilings across the area today decreasing from
VFR over Illinois to MVFR in eastern Missouri and down to IFR in
central and parts of southeast Missouri. Patchy drizzle is also
possible across the region today, particularly in central
Missouri. Ceilings will likely drop slowly overnight tonight, with
more patchy drizzle over parts of the area.

Specifics for KSTL:

Ceilings will likely stay in MVFR range today. Short-range
guidance is indicating that there will be a period of ceilings
below 2000ft for this morning, and this seems reasonable given
weak low level flow from the northeast and a few obs with ceilings
around 1000ft upstream. Could see a little drizzle in the area
today, but greater chances for drizzle should be over central
Missouri. Expect that MVFR ceilings will continue through tonight.

Carney

&&

.PRELIMINARY POINT TEMPS/POPS:
Saint Louis     35  31  41  34 /  10  10  10   5
Quincy          32  29  38  31 /  10  10  10  10
Columbia        35  33  41  34 /  10  10  10   5
Jefferson City  37  34  42  34 /  10  10  10   5
Salem           35  29  41  31 /  10  10   5   0
Farmington      36  30  43  31 /  10  10  10   0

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX






AREA FORECAST DISCUSSION

NWS BISMARCK ND

 944 AM CST FRI DEC 19 2014

.UPDATE...
ISSUED AT 943 AM CST FRI DEC 19 2014

WILL EXTEND AREAS OF FOG FOR A FEW MORE HOURS NORTHWEST. OTHERWISE
AS FOG LIFTS PATCHY FREEZING DRIZZLE HAS DIMINISHED. TEMPERATURES
AND WINDS LOOK OK.

UPDATE ISSUED AT 640 AM CST FRI DEC 19 2014

VISIBILITIES IN FOG NORTH AND EAST CONTINUE TO VARY FROM TIME TO
TIME AND PLACE TO PLACE. THERE WAS GENERAL IMPROVEMENT IN
VISIBILITIES. THE DENSE FOG ADVISORY NORTHWEST WAS ALLOWED TO
EXPIRE. A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED FOR FOG...SOME
OF IT LOCALLY DENSE.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 405 AM CST FRI DEC 19 2014

FOG AND LOW CLOUDS ARE THE MAIN CONCERNS IN THE SHORT TERM.

CURRENT SURFACE ANALYSIS  INDICATES LOW PRESSURE IN THE LEE OF THE
ROCKIES WITH A TROUGH EXTENDING FROM NORTHERN ALBERTA TO THE WESTERN
DAKOTAS. AT UPPER LEVELS A BROAD TROUGH EXTENDED OVER THE CANADIAN
AND NORTHERN US PLAINS. A RATHER SHARP WESTERN EDGE TO LOW CLOUDS
EXTENDED FROM NEAR WILLISTON ACROSS LAKE SAKAKAWEA TO EAST OF
BISMARCK. MID LEVEL CLOUDS WERE ALONG AND SOUTH/WEST OF THE MISSOURI
RIVER AT 3 AM CST. EXPECT THE LOW CLOUDS TO CLEAR FROM WEST TO EAST
ACROSS SOUTH CENTRAL NORTH DAKOTA...BUT LATEST HRRR MODEL INDICATES
CLOUDS HANGING IN ACROSS THE NORTH. A SHORTWAVE ALOFT ON THE WESTERN
EDGE OF THE UPPER TROUGH WAS DIGGING SOUTHEAST ACROSS SOUTHWESTERN
NORTH DAKOTA INTO WESTERN SOUTH DAKOTA...AND MAY BE THE DRIVING
FORCE FOR THE MID CLOUDS MOVING IN AND THE LOWER CLOUDS DISSIPATING.

DENSE FOG STILL EVIDENT AT WILLISTON...ALTHOUGH VISIBILITIES HAVE
IMPROVED IN THE LAST HOUR AT OTHER PLACES WITHIN THE DENSE FOG
ADVISORY...SUCH AS TIOGA/STANLEY/CROSBY. BUT MINOT VISIBILITY IS ON
A DOWNWARD TREND. THUS WILL KEEP THE DENSE FOG ADVISORY GOING UNTIL
6 AM AND THEN RE-EVALUATE.

OTHERWISE WARM ADVECTION TODAY SHOULD ALLOW TEMPERATURES TO RISE
INTO THE MID/UPPER 20S NORTH AND EAST OF THE MISSOURI RIVER...AND
WELL INTO THE MID AND UPPER 30S SOUTH AND WEST OF THE RIVER. TONIGHT
A SHORTWAVE RIDGE ALOFT ENTERS WESTERN NORTH DAKOTA AHEAD OF AN
UPPER LEVEL SHORTWAVE MOVING EASTWARD OUT OF THE ROCKIES. LOWS
TONIGHT SHOULD REMAIN ABOVE AVERAGE IN THE TEENS AND LOWER 20S.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 405 AM CST FRI DEC 19 2014

THE SHORT TERM ISSUES...LOW CLOUDS AND LIGHT PRECIPITATION
INCLUDING FREEZING RAIN/FREEZING DRIZZLE AND PATCHY FOG...
CONTINUE INTO THE LONG TERM AS THE FORECAST AREA REMAINS UNDER A
MEAN TROUGH SURFACE AND ALOFT. WAVES COMING THROUGH SATURDAY AND
AGAIN SUNDAY ARE WEAK AND MOISTURE STARVED. HOWEVER...WITH WARMER
AIR ADVECTING IN ALOFT AHEAD OF EACH WAVE THERE IS A RISK OF
FREEZING RAIN SATURDAY MORNING / FREEZING DRIZZLE WITH LOW STRATUS
CLOUDS. WARM ADVECTION CONTINUES CHANGING ANY PRECIPITATION IN THE
SOUTHWEST TO RAIN WITH SURFACE TEMPERATURES INTO THE MID 30S
SATURDAY AFTERNOON. A SIMILAR SCENARIO SETS UP FOR SUNDAY.

THE MID LEVEL LOW...CUTTING OFF OVER WISCONSIN...WILL BLOCK THE
FLOW PATTERN UP ACROSS THE NORTHERN PLAINS. THIS WILL ALLOW COLDER
AIR TO SPILL IN FOR TUESDAY. LOOKING AHEAD TO CHRISTMAS DAY...THE
LOW TO THE EAST...AND HIGH PRESSURE MOVING ACROSS THE NORTHERN
ROCKIES...ALLOW A STEADY FLOW OF COLDER AIR INTO NORTH
DAKOTA...THAT WILL CONTINUE AT LEAST THROUGH THE HOLIDAY WEEKEND.
STILL THOUGH...TEMPERATURES ARE CLOSE TO WHAT IS NORMAL FOR THE
END OF DECEMBER...AROUND 20 DAYTIME AND SINGLE DIGITS ABOVE AND
BELOW AT NIGHT. PERIODS OF FLURRIES...MAYBE A FEW TENTHS INCH OF
SNOW AT MOST EVERY OTHER DAY OR SO...LOOKS TO OCCUR THROUGH THE
CHRISTMAS HOLIDAY WEEKEND.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1245 AM CST FRI DEC 19 2014

A MOIST SOUTHERLY FLOW CONTINUES TO PRODUCE WIDESPREAD MVFR-IFR
STRATUS ACROSS CENTRAL AND NORTHWEST NORTH DAKOTA. A WEAK TROUGH OF
LOW PRESSURE WAS PROVIDING MID CLOUDS ACROSS SOUTHWEST NORTH
DAKOTA. THIS TROUGH WILL CLEAR THE STRATUS AT KISN AROUND 15 UTC.
KMOT AND KJMS WILL REMAIN IN MVFR-IFR STRATUS INTO THIS
AFTERNOON. THE MOISTURE REMAINS TRAPPED ALONG THE CANADIAN BORDER
WHICH COULD KEEP KMOT IN THE MVFR-IFR STRATUS AT LEAST THROUGH MID
AFTERNOON. ONCE THE STRATUS CLEARS THE TAF SITES VFR CONDITIONS
ARE THEN EXPECTED THROUGH THE REMAINDER OF THE FORECAST PERIOD.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...WAA
SHORT TERM...JV
LONG TERM...JPM
AVIATION...JV







AREA FORECAST DISCUSSION

NWS BISMARCK ND

 641 AM CST FRI DEC 19 2014

.UPDATE...
ISSUED AT 640 AM CST FRI DEC 19 2014

VISIBILITIES IN FOG NORTH AND EAST CONTINUE TO VARY FROM TIME TO
TIME AND PLACE TO PLACE. THERE WAS GENERAL IMPROVEMENT IN
VISIBILITIES. THE DENSE FOG ADVISORY NORTHWEST WAS ALLOWED TO
EXPIRE. A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED FOR FOG...SOME
OF IT LOCALLY DENSE.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 405 AM CST FRI DEC 19 2014

FOG AND LOW CLOUDS ARE THE MAIN CONCERNS IN THE SHORT TERM.

CURRENT SURFACE ANALYSIS  INDICATES LOW PRESSURE IN THE LEE OF THE
ROCKIES WITH A TROUGH EXTENDING FROM NORTHERN ALBERTA TO THE WESTERN
DAKOTAS. AT UPPER LEVELS A BROAD TROUGH EXTENDED OVER THE CANADIAN
AND NORTHERN US PLAINS. A RATHER SHARP WESTERN EDGE TO LOW CLOUDS
EXTENDED FROM NEAR WILLISTON ACROSS LAKE SAKAKAWEA TO EAST OF
BISMARCK. MID LEVEL CLOUDS WERE ALONG AND SOUTH/WEST OF THE MISSOURI
RIVER AT 3 AM CST. EXPECT THE LOW CLOUDS TO CLEAR FROM WEST TO EAST
ACROSS SOUTH CENTRAL NORTH DAKOTA...BUT LATEST HRRR MODEL INDICATES
CLOUDS HANGING IN ACROSS THE NORTH. A SHORTWAVE ALOFT ON THE WESTERN
EDGE OF THE UPPER TROUGH WAS DIGGING SOUTHEAST ACROSS SOUTHWESTERN
NORTH DAKOTA INTO WESTERN SOUTH DAKOTA...AND MAY BE THE DRIVING
FORCE FOR THE MID CLOUDS MOVING IN AND THE LOWER CLOUDS DISSIPATING.

DENSE FOG STILL EVIDENT AT WILLISTON...ALTHOUGH VISIBILITIES HAVE
IMPROVED IN THE LAST HOUR AT OTHER PLACES WITHIN THE DENSE FOG
ADVISORY...SUCH AS TIOGA/STANLEY/CROSBY. BUT MINOT VISIBILITY IS ON
A DOWNWARD TREND. THUS WILL KEEP THE DENSE FOG ADVISORY GOING UNTIL
6 AM AND THEN RE-EVALUATE.

OTHERWISE WARM ADVECTION TODAY SHOULD ALLOW TEMPERATURES TO RISE
INTO THE MID/UPPER 20S NORTH AND EAST OF THE MISSOURI RIVER...AND
WELL INTO THE MID AND UPPER 30S SOUTH AND WEST OF THE RIVER. TONIGHT
A SHORTWAVE RIDGE ALOFT ENTERS WESTERN NORTH DAKOTA AHEAD OF AN
UPPER LEVEL SHORTWAVE MOVING EASTWARD OUT OF THE ROCKIES. LOWS
TONIGHT SHOULD REMAIN ABOVE AVERAGE IN THE TEENS AND LOWER 20S.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 405 AM CST FRI DEC 19 2014

THE SHORT TERM ISSUES...LOW CLOUDS AND LIGHT PRECIPITATION
INCLUDING FREEZING RAIN/FREEZING DRIZZLE AND PATCHY FOG...
CONTINUE INTO THE LONG TERM AS THE FORECAST AREA REMAINS UNDER A
MEAN TROUGH SURFACE AND ALOFT. WAVES COMING THROUGH SATURDAY AND
AGAIN SUNDAY ARE WEAK AND MOISTURE STARVED. HOWEVER...WITH WARMER
AIR ADVECTING IN ALOFT AHEAD OF EACH WAVE THERE IS A RISK OF
FREEZING RAIN SATURDAY MORNING / FREEZING DRIZZLE WITH LOW STRATUS
CLOUDS. WARM ADVECTION CONTINUES CHANGING ANY PRECIPITATION IN THE
SOUTHWEST TO RAIN WITH SURFACE TEMPERATURES INTO THE MID 30S
SATURDAY AFTERNOON. A SIMILAR SCENARIO SETS UP FOR SUNDAY.

THE MID LEVEL LOW...CUTTING OFF OVER WISCONSIN...WILL BLOCK THE
FLOW PATTERN UP ACROSS THE NORTHERN PLAINS. THIS WILL ALLOW COLDER
AIR TO SPILL IN FOR TUESDAY. LOOKING AHEAD TO CHRISTMAS DAY...THE
LOW TO THE EAST...AND HIGH PRESSURE MOVING ACROSS THE NORTHERN
ROCKIES...ALLOW A STEADY FLOW OF COLDER AIR INTO NORTH
DAKOTA...THAT WILL CONTINUE AT LEAST THROUGH THE HOLIDAY WEEKEND.
STILL THOUGH...TEMPERATURES ARE CLOSE TO WHAT IS NORMAL FOR THE
END OF DECEMBER...AROUND 20 DAYTIME AND SINGLE DIGITS ABOVE AND
BELOW AT NIGHT. PERIODS OF FLURRIES...MAYBE A FEW TENTHS INCH OF
SNOW AT MOST EVERY OTHER DAY OR SO...LOOKS TO OCCUR THROUGH THE
CHRISTMAS HOLIDAY WEEKEND.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1245 AM CST FRI DEC 19 2014

A MOIST SOUTHERLY FLOW CONTINUES TO PRODUCE WIDESPREAD MVFR-IFR
STRATUS ACROSS CENTRAL AND NORTHWEST NORTH DAKOTA. A WEAK TROUGH OF
LOW PRESSURE WAS PROVIDING MID CLOUDS ACROSS SOUTHWEST NORTH
DAKOTA. THIS TROUGH WILL CLEAR THE STRATUS AT KISN AROUND 15 UTC.
KMOT AND KJMS WILL REMAIN IN MVFR-IFR STRATUS INTO THIS
AFTERNOON. THE MOISTURE REMAINS TRAPPED ALONG THE CANADIAN BORDER
WHICH COULD KEEP KMOT IN THE MVFR-IFR STRATUS AT LEAST THROUGH MID
AFTERNOON. ONCE THE STRATUS CLEARS THE TAF SITES VFR CONDITIONS
ARE THEN EXPECTED THROUGH THE REMAINDER OF THE FORECAST PERIOD.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...JPM
SHORT TERM...JV
LONG TERM...JPM
AVIATION...JV





AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 540 AM CST FRI DEC 19 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CST FRI DEC 19 2014

THE MAIN FORECAST CHALLENGE INTO TONIGHT IS WITH THE LOW LEVEL
MOISTURE AND WHETHER IT WILL BE ENOUGH TO PRODUCE SOME FREEZING
DRIZZLE OR FLURRIES.

CURRENTLY...A BAND OF 1-2KFT STRATUS THAT EXTENDS FROM NORTHWEST
WISCONSIN DOWN THROUGH SOUTHERN WISCONSIN HAS BEEN PRODUCING SOME
FLURRIES DUE TO SOME WEAK LIFT ASSOCIATED WITH A COLD FRONT THAT
EXTENDS FROM SOUTHERN MICHIGAN WEST-NORTHWEST INTO WESTERN
WISCONSIN. THIS FEATURE WILL PULL EASTWARD THIS MORNING/AFTERNOON
AND SHOULD TAKE THESE FLURRIES EAST AS WELL. TO THE SOUTHWEST
TOWARD DES MOINES...ANOTHER BAND OF LOW LEVEL MOISTURE ASSOCIATED
WITH SOME RETURN SOUTHERLY FLOW/WARM AIR ADVECTION HAS FORMED SOME
FREEZING DRIZZLE AND FLURRIES IN THAT REGION. THE QUESTION FOR
TODAY/TONIGHT IS WHETHER THAT FREEZING DRIZZLE/FLURRIES HOLDS
TOGETHER.

19.00Z NAM/GFS AND 19.06Z RAP SOUNDINGS CERTAINLY SHOW THE SURFACE
TO 800MB LAYER MOISTENING UP THROUGH TONIGHT...ITS JUST A MATTER
OF WHETHER THERE IS ANY LIFT THERE. GIVEN THAT THERE CURRENTLY IS
SOME PRECIPITATION OCCURRING UPSTREAM...THERE DOES APPEAR TO BE
ENOUGH LIFT AND HAVE GONE AHEAD AND ADDED A MENTION OF SOME
PATCHY FREEZING DRIZZLE IN FOR TODAY IN SE MN/NE IA WITH IT
SPREADING EASTWARD OVERNIGHT AS THE MOISTURE SHIFTS EAST. DMX HAS
REPORTED SOME FLURRIES OCCURRING AS WELL AT THE MOMENT MEANING
THAT THERE IS SOME ICE BEING INTRODUCED IN THE LOW LEVELS THOUGH
MOST OF THE FORECAST SOUNDINGS SHOW THAT SATURATED LAYER BEING TOO
WARM TONIGHT TO PRODUCE ANY FLURRIES LOCALLY. NOT SURE WHETHER
THIS FREEZING DRIZZLE IS GOING TO BE ADVISORY WORTHY GIVEN THAT
THERE IS NOT MUCH FOCUS FOR LOW LEVEL LIFT...BUT CONDITIONS WILL
HAVE TO BE MONITORED SINCE AIR/ROAD TEMPERATURES WILL BE BELOW
FREEZING.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 333 AM CST FRI DEC 19 2014

THE PATTERN BECOMES MORE ACTIVE GOING INTO THE LATER PORTION OF
THE WEEKEND ON INTO EARLY NEXT WEEK AS A SERIES OF MID LEVEL SHORT
WAVE TROUGHS PROPAGATE ON THROUGH. THE NEXT DECENT CHANCE FOR
PRECIPITATION APPEARS TO COME IN ON SUNDAY AS LOW LEVEL WARM AIR
ADVECTION WILL COMBING WITH SOME WEAK 700MB TROUGHING TO DEVELOP
SOME PRECIPITATION. PRECIPITATION TYPE IS TRICKY WITH THIS SYSTEM
AS THERE IS A WEAK WARM LAYER THAT REACHES +1 TO +2C AND WOULD
MELT SOME OF THE SNOW THAT FALLS THROUGH IT. THERE ALSO APPEARS
TO BE A DRY LAYER BETWEEN THE 700MB MOISTURE AND SURFACE/LOW LEVEL
MOISTURE WHICH BRINGS INTO QUESTION HOW DEEP THE LIFT REALLY WILL
BE. SURFACE TEMPERATURES WILL ALSO BE CLIMBING TOWARD AND ABOVE
FREEZING WHICH COMPLICATES HOW MUCH SNOW COULD ACCUMULATE. KEPT
SNOW ACCUMULATIONS ON THE LOW SIDE...HALF INCH OR LESS...GIVEN ALL
OF THE QUESTIONS WITH THIS ROUND OF PRECIP.

A DEEPER TROUGH DEVELOPS ACROSS THE DAKOTAS SUNDAY NIGHT INTO
TUESDAY AND WILL BRING A MORE WIDESPREAD SHOT OF
PRECIPITATION...MAINLY RAIN BEFORE CHANGING OVER TO SNOW ON THE
BACKSIDE TUESDAY. THE 19.00Z GFS/ECMWF ARE IN DECENT AGREEMENT
WITH THIS SYSTEM IN REGARD TO TIMING BUT ARE DIFFERENT WITH THEIR
PROGRESSION OF THE SURFACE LOW WITH THE GFS DIGGING DEEPER EARLIER
WITH THE ECMWF KEEPING PRECIPITATION AROUND A TAD LONGER. BOTH
MODELS HAVE THE SNOW OFF TO THE EAST BY CHRISTMAS DAY WITH JUST
SOME WEST TO NORTHWEST WINDS IN THE WAKE OF THE SYSTEM.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 540 AM CST FRI DEC 19 2014

EXTENSIVE DECK OF MVFR CLOUD COVER IN PLACE ACROSS THE REGION.
THERE IS A THIN SLIVER OF VFR CLOUD CIGS EXTENDING FROM VCNTY KRST
SOUTHEASTWARD INTO NORTHEAST IA...BUT THINKING THIS WILL QUICKLY
FILL IN WITH MVFR CLOUD AS WELL THIS MORNING. IN ADDITION...SOME
PATCHY FREEZING DRIZZLE MAY SEEN ACROSS PORTIONS OF NORTHEAST IA
INTO SOUTHEAST MN BY MID-MORNING INTO THIS AFTERNOON AS SOUTHERLY
FLOW BRINGS MORE MOISTURE INTO THE AREA AHEAD OF A TROUGH OF LOW
PRESSURE MOVING OUT OF THE PLAINS.EXPECTING PATCHY FREEZING
DRIZZLE TO SPREAD EAST OF THE MISSISSIPPI LATER TONIGHT INTO
SATURDAY MORNING AS THE TROUGH MOVES INTO THE REGION. SINCE THIS
FREEZING DRIZZLE IS EXPECTED TO BE PATCHY IN NATURE...DECIDED TO
KEEP OUT OF THE BODY OF THE TAF FOR NOW...BUT WILL CONTINUE TO
MONITOR CLOSELY. OTHERWISE...LOOK FOR KRST CIGS TO SLIP FROM MVFR
TODAY INTO IFR AFTER 04Z.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&

$$

SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...DAS




AREA FORECAST DISCUSSION

NWS RENO NV

 250 PM PST FRI DEC 19 2014

.SYNOPSIS...
CHANCES FOR RAIN AND SNOW WILL GRADUALLY DIMINISH FROM SOUTH TO
NORTH THROUGH SATURDAY. ANY AMOUNTS WILL REMAIN LIGHT. HIGH
PRESSURE WILL BUILD IN FOR EARLY NEXT WEEK WITH MILD TEMPERATURES.
A STRONG COLD FRONT IS POSSIBLE LATE WEDNESDAY INTO THURSDAY WITH
SOME GUSTY WINDS, RAIN AND SNOW.

&&

.SHORT TERM...
MAIN BAND OF RAIN/SNOW IS NOW ALONG A SOUTH LAKE TO BATTLE MTN.
LINE AND IS PUSHING SOUTH AND EAST. THIS BAND WILL WEAKEN OVER THE
NEXT FEW HOURS WITH LIGHT AMOUNTS UP TO A TENTH OF AN INCH.
OTHERWISE ONLY EXPECT ISOLD SHOWERS WITH ONE EXCEPTION. BOTH THE
NAM AND HRRR SHOW ANOTHER BAND OF PRECIP DEVELOPING OVER CENTRAL
CA AND MOVING NORTHEAST INTO THE TAHOE BASIN THIS EVENING. A WEAK
WAVE IS PRESENT IN SATELLITE IMAGERY NEAR 127W AND THIS LOOKS LIKE
IT WOULD BE THE TRIGGER. KEPT SCT SNOW SHOWERS GOING IN THE SIERRA
FROM CARSON TO YUBA PASSES FOR THIS WAVE ALTHOUGH IT MAY BE MORE
WIDESPREAD THAN THIS. ANOTHER COUPLE INCHES OF SNOW REMAIN
POSSIBLE IN THIS BAND IF IT DEVELOPS.

A MILD NIGHT TONIGHT WITH CONTINUED CLOUD COVER AS ANOTHER STORM
MOVES INTO OREGON FOR SATURDAY. WE WILL CONTINUE TO SEE ABUNDANT
CLOUD COVER, BUT THE FORCING WITH THIS NEXT STORM WILL REMAIN WILL
NORTH WITH THE UPPER JET INTO THE COLUMBIA RIVER. THE EXCEPTION
WILL BE NORTH OF A SUSANVILLE TO GERLACH LINE WHERE SOME GOOD
ISENTROPIC LIFT IS SHOWING UP SATURDAY MORNING. INCREASED THE
THREAT OF RAIN/SNOW THERE WHILE KEEPING IT LOW CHANCE TO SLIGHT
CHANCE FURTHER SOUTH. IT APPEARS THERE WILL BE ABOUT A TENTH TO
QUARTER INCH OF PRECIP WITH IT.

THE GREATEST UNCERTAINTY THERE WILL BE THE SNOW LEVEL AND PRECIP
TYPE ON VALLEY FLOORS. NORMALLY IN A GOOD WARM AIR ADVECTION EVENT
LIKE THIS IT WOULD START AS SNOW WITH SOME ISOTHERMAL TEMP
PROFILES. HOWEVER, SURFACE TEMPS AND DEWPOINTS ARE 35-40 AND SEE
NO SIGNIFICANT DRYING OR COOLING TONIGHT AS MOISTURE AND CLOUDS
CONTINUE TO ARRIVE. RIGHT NOW, PUT SNOW LEVELS 4500-5000 FEET WITH A
RAIN/SNOW MIX IN THE SURPRISE VALLEY. IF IT IS ALL SNOW 1-2 INCHES
OF SNOW IS POSSIBLE BUT MY GUESS IS IT WILL BE IN THE FORM OF
RAIN.

BEHIND THE WARM FRONT, MID/HIGH CLOUDS WILL DIMINISH SATURDAY
NIGHT INTO SUNDAY. SOME SCATTERED LOW CLOUDS WILL CONTINUE AS
ABUNDANT LOW LEVEL MOISTURE GETS TRAPPED UNDER A SUBSIDENCE
INVERSION WITH THE STRONG RIDGE BUILDING IN. TEMPERATURES WILL
REMAIN MILD AND ABOVE NORMAL INTO EARLY NEXT WEEK WITH 50S DURING
THE DAY AND 20S AND 30S OVERNIGHT, COLDEST IN SIERRA VALLEYS.
WALLMANN

.LONG TERM...TUESDAY THROUGH FRIDAY...
HIGH PRESSURE OVER THE WEST WILL GIVE WAY AROUND MID WEEK AS A
FAST-MOVING LOW PRESSURE SYSTEM MOVES INTO THE WEST COAST ON
CHRISTMAS EVE. THE GFS KEEPS THE SYSTEM FLAT AS IT MOVES THROUGH
THE REGION WHILE THE ECMWF/UKMET ARE BRINGING A STRONGER, DIGGING
SYSTEM INTO THE REGION. THE NWS WEATHER PREDICTION CENTER CONCURS
WITH A DIGGING SYSTEM AND THIS SOUNDS APPROPRIATE AS STRONG
SHORTWAVE ENERGY MOVING OFF OF JAPAN SATURDAY ARRIVES AT THE WEST
COAST ON WEDNESDAY (WHICH WOULD ENHANCE THE SYSTEM).

AS FAR AS THE DETAILS, THE DEVIL REMAINS AS THE 12Z ECMWF AND GEM
ARE NOW IMPLYING SOME SPLITTING AS THE SYSTEM MOVES INTO THE SIERRA
AND WESTERN NEVADA. I WOULD STILL EXPECT PRECIPITATION (AT LEAST IN
THE SIERRA AND IN THE BASIN NORTH OF HIGHWAY 50) WHETHER THE SYSTEM
BEGINS TO SPLIT OR NOT, ESPECIALLY AS THE GFS/EC SHOW A MODERATE
MOISTURE FEED (PWATS APPROACHING ONE INCH) BEING PULLED OFF OF A
SUBTROPICAL LOW NEAR HAWAII. HOWEVER, THE SPLIT WOULD LOWER
PRECIPITATION TOTALS AS THE SYSTEM`S COLD FRONT WEAKENS/FRACTURES.
ALSO, IT WOULD DELAY THE PUNCH OF COLD AIR ENOUGH THAT PRECIPITATION
WOULD START AS RAIN INITIALLY BELOW 5000-5500 FEET RATHER THAN BE A
MAINLY SNOW EVENT PER THE UNSPLIT/CONSOLIDATED SOLUTIONS.

AS FAR AS IMPACTS FOR EASTERN CALIFORNIA AND WESTERN NEVADA FOR THE
CHRISTMAS HOLIDAY, WIND GUSTS TO 35-45 MPH IN THE LOWER ELEVATIONS
ARE POSSIBLE WEDNESDAY WHICH WOULD CLEAR OUT ANY HAZE/POLLUTANTS IN
THE VALLEYS AND WARM HIGHS INTO THE 50S TO NEAR 60. PRECIPITATION
WISE, SNOW OR RAIN AND SNOW MAY START TO MOVE INTO AREAS NORTH OF
INTERSTATE 80 BY LATE WEDNESDAY AFTERNOON, THEN ACROSS THE
RENO-TAHOE AREA DURING CHRISTMAS EVE. THOSE TRAVELING CHRISTMAS EVE
AND CHRISTMAS MORNING SHOULD KEEP AN EYE ON THE FORECAST WITH
POTENTIAL IMPACTS DUE TO SNOW IN THE SIERRA AND ON THE LOWER VALLEY
FLOORS.

AFTER THE SYSTEM PASSES, A COLD NORTH SURFACE FLOW IS EXPECTED TO
KEEP AFTERNOON HIGHS FOR VALLEYS ON THURSDAY/CHRISTMAS DAY AND
FRIDAY IN THE 30S. THE CAVEAT IS THAT IF AT LEAST A FEW INCHES OF
SNOW FALLS ON CHRISTMAS EVE HIGHS ARE LIKELY TO REMAIN IN THE 20S
ALL DAY FOR LATE NEXT WEEK. FOR LOWS, SNOWFALL WOULD PUSH LOWS FROM
THE SINGLE DIGITS AND TEENS TO BELOW ZERO FOR MANY VALLEY LOCATIONS.
SNYDER

&&

.AVIATION...
A FRONT MOVING THROUGH THE AREA IS PRODUCING -SN/SN AND IFR
CONDITIONS IN THE SIERRA WITH ISOLD/SCATTERED SHOWERS AND HIGHER
TERRAIN OBSCURATION IN WESTERN NEVADA, MAINLY NORTH OF HIGHWAY 50.
THE FRONT IS ALSO KICKING UP WINDS GUSTS TO 20-25 KTS IN WESTERN
NEVADA NEAR/SOUTH OF I-80 AND DOWN INTO EASTERN MONO COUNTY.
FINALLY, TURBULENCE AND LIGHT RIMING ARE ALSO A GOOD BET OVER THE
SIERRA AND INTO WESTERN NEVADA WITH A RECENT PIREP INDICATING THIS
BETWEEN 090-190 MSL NEAR RENO.

FOR THIS EVENING, ANOTHER UPPER DISTURBANCE APPROACHING THE NORTHERN
CALIFORNIA COAST IS EXPECTED TO ENHANCE NORTHERN SIERRA SNOWFALL.
GIVEN THAT THE NEXT ROUND OF SIERRA SNOW WILL ARRIVE AFTER SUNSET
THERE COULD BE AN INCH OR TWO OF ACCUMULATION ON UNTREATED TARMACS
AND RUNWAYS AT KTRK AND KTVL. PLENTY OF MOISTURE AND A FEW LEFTOVER
-SHSN SHOULD ALLOW AREAS OF LOW CIGS AND TERRAIN OBSCURATION TO
PERSIST OVERNIGHT FOR THE SIERRA AND PORTIONS OF NORTHEAST
CALIFORNIA.

SATURDAY, ONE MORE ROUND OF LIGHT LOWER VALLEY RAIN AND MOUNTAIN
SNOW WILL AFFECT NORTHEAST CALIFORNIA AND NORTHERN NEVADA. THIS WILL
MEAN HIGHER TERRAIN OBSCURATION AND PERIODS OF MVFR CIGS FOR
NORTHERN SIERRA (KTVL/KTRK) TERMINALS, AS WELL AS THE POSSIBILITY
FOR BRIEF MVFR CIGS OUT INTO WESTERN NEVADA NORTH OF INTERSTATE 80.
SNYDER

&&

.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&

$$

FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)






AREA FORECAST DISCUSSION...UPDATED

NWS RENO NV

 847 AM PST FRI DEC 19 2014

.UPDATE...
MAIN PRECIP BAND IS HOLDING TOGETHER FAIRLY WELL AS IT MOVES
TOWARD THE I-80 CORRIDOR THIS MORNING. IT HAS ALSO BEEN SPILLING
OVER FAIRLY WELL INTO THE LEESIDE VALLEYS WHICH IS MORE THAN
WE EXPECTED YESTERDAY AND LAST NIGHT. GIVEN THE NATURE OF THE
BAND, THE SPILLOVER AND THE LATEST HRRR WHICH KEEPS THE BAND
INTACT THROUGH I-80 WILL UPDATE THE FORECAST. THE MAIN CHANGE IS
TO INCREASE THE CHANCES OF RAIN/SNOW ALONG THE I-80 CORRIDOR
THROUGH EARLY AFTERNOON. THE RAIN/SNOW WILL ONLY LAST 2-4 HOURS,
LONGEST IN THE SIERRA, BUT IT WILL BE NOTICEABLE. PRECIP AMOUNTS
OF AROUND 1/4 INCH FOR THE TAHOE BASIN WITH UP TO A TENTH IN
WESTERN NEVADA.

SNOW LEVELS ARE RUNNING SLIGHTLY HIGHER THAN FORECAST WITH THE
CHICO PROFILER AT 7000 FEET SIGNIFICANTLY HIGHER. SLIDE TEMPS ARE
RUNNING 22-23 DEGREES AND WHILE THE TAHOE BASIN IS ABOVE FREEZING,
DEW POINTS ARE LOW. THIS SHOULD RESULT IN WET BULBING THAT WILL
BRING SNOW TO LAKE LEVEL AS WELL. WILL RAINS SNOW LEVELS SLIGHTLY
TO 5500-6000 FEET WITH LIGHT AMOUNTS OF 1-3 INCHES FOR THE BASIN
AND PERHAPS UP TO 6 INCHES NEAR THE CREST ABOVE 7000 FEET. AFTER
THE BAND MOVES THROUGH, EXPECT ONLY ISOLD-SCT SHOWERS INTO THE
EVENING. WALLMANN

&&

.PREVIOUS DISCUSSION... /ISSUED 221 AM PST FRI DEC 19 2014/

SYNOPSIS...
CHANCES FOR RAIN AND SNOW WILL PERSIST NORTH OF HIGHWAY 50 THROUGH
SATURDAY AS COUPLE OF WEAK SYSTEMS BRUSH NORTHEASTERN CALIFORNIA AND
WESTERN NEVADA. HIGH PRESSURE WILL THEN BUILD SUNDAY THROUGH THE
FIRST PART OF NEXT WEEK. A COOLING TREND AND SNOW ARE POSSIBLE FOR
CHRISTMAS EVE.

SHORT TERM...
MINOR ADJUSTMENTS MADE TO THE ONGOING FORECAST THIS MORNING AS A
WEAK SYSTEM BRUSHES ACROSS NORTHEASTERN CALIFORNIA AND NORTHERN
NEVADA.

A PRECIPITATION BAND AHEAD OF THE MAIN COLD FRONT MOVED THROUGH
LASSEN AND PLUMAS COUNTIES EARLY THIS MORNING BRINGING SNOW
SHOWERS TO THOSE AREAS. THE WEB CAM AT BOGARD REST AREA (AROUND 5600
FEET) SHOWED SNOW ACCUMULATING QUICKLY BETWEEN MIDNIGHT AND 1AM
UNDER THE PRECIPITATION BAND. TRAVELERS SHOULD CHECK ROAD
CONDITIONS BEFORE HEADING OUT THIS MORNING AS ROADS MAY BE SLICK OR
SNOW COVERED. AS THE COLD FRONT APPROACHES THE REGION, SNOW
LEVELS WILL REMAIN NEAR 6000-6500 FEET AROUND INTERSTATE 80 AND
4500-5000 FEET NEAR THE OREGON BORDER. LIGHT SNOW AMOUNTS OF UP TO
A COUPLE INCHES ARE POSSIBLE ABOVE 5500 FEET THROUGH THE MORNING
WITH HIGHER AMOUNTS TO 6 INCHES NEAR THE SIERRA CREST.

THE SYSTEM PUSHES THROUGH THE REGION TONIGHT WITH MOIST UPSLOPE FLOW
ALLOWING RESIDUAL SHOWERS TO CONTINUE ALONG THE CREST. THE NEXT
ROUND OF PRECIPITATION PUSHES INTO AREAS FROM THE TAHOE BASIN
EXTENDING NORTH INTO NORTHERN LASSEN, WASHOE, AND CHURCHILL COUNTIES
AS A RESULT OF WARM AIR ADVECTION. AGAIN THE BEST CHANCES APPEAR TO
REMAIN RIGHT ALONG THE NEVADA/OREGON BORDER WITH CHANCES DROPPING
OFF SIGNIFICANTLY FURTHER SOUTH. MODEL SOUNDINGS CONTINUE TO SHOW AN
ISOTHERMAL LAYER WHICH MAY ALLOW SNOW LEVELS NEAR THE OREGON BORDER
TO REMAIN NEAR VALLEY FLOORS, BUT SNOW LEVELS WILL BE ON THE RISE
LATE SATURDAY INTO SUNDAY AS THE WARM FRONT PUSHES THROUGH.

AFTER THIS SYSTEM PASSES THROUGH SATURDAY NIGHT, THE RIDGE AMPLIFIES
OFF THE WEST COAST BRINGING A WARMING AND DRYING TREND. SKIES WILL
REMAIN FAIRLY CLOUDY UNDER THE DIRTY RIDGE PATTERN, ESPECIALLY NORTH
OF INTERSTATE 80, WHICH WILL HELP TO MODERATE TEMPERATURES
OVERNIGHT. OTHERWISE RIDGING THROUGH THE WEEKEND MAY ALLOW SURFACE
INVERSIONS TO DEVELOP WHICH WILL RESULT IN FASTER WARMING FOR RIDGE
TOP TEMPERATURES THAN THE VALLEYS. WEISHAHN

LONG TERM...MONDAY THROUGH CHRISTMAS...

HIGH PRESSURE OVER THE WEST WILL GIVE WAY AROUND MID WEEK AS LOW
PRESSURE MOVES INTO THE WEST COAST. MODELS SOLUTIONS SHOWED A
MODERATE AMOUNT OF AGREEMENT SO FORECAST CONFIDENCE IS MEDIUM IN A
SYSTEM MOVING INTO THE REGION ON CHRISTMAS EVE. MODELS CONTINUE TO
SHOW A FRONT REACHING NORTHERN CALIFORNIA AND NORTHWEST NEVADA ON
WEDNESDAY. THE FRONT SHOULD INCREASE GUSTS TO NEAR 45 MPH IN THE
LOWER ELEVATIONS, WHICH WILL HELP CLEAR OUT ANY HAZE/POLLUTANTS IN
THE VALLEYS AND MAY WARM HIGHS INTO THE 50S TO NEAR 60.
PRECIPITATION MAY START TO MOVE INTO AREAS NORTH OF INTERSTATE 80 BY
LATE WEDNESDAY AFTERNOON, THEN ACROSS THE RENO-TAHOE AREA DURING
CHRISTMAS EVE. THOSE TRAVELING CHRISTMAS EVE AND CHRISTMAS MORNING
SHOULD KEEP AN EYE ON THE FORECAST FOR POTENTIAL IMPACTS DUE TO
SNOW OVER THE SIERRA PASSES AND ON THE NEVADA VALLEY FLOORS. AFTER
THE SYSTEM PASSES, A COLD NORTH SURFACE FLOW COULD KEEP AFTERNOON
HIGHS ON CHRISTMAS DAY IN THE 20S AND 30S. BRONG

AVIATION...

COLD FRONT MOVING THROUGH THE AREA IS PRODUCING SNOW AND IFR
CONDITIONS IN THE NORTHERN SIERRA WITH SCATTERED SHOWERS AND MVFR
CONDITIONS EAST OF THE SIERRA. THE FRONT IS FORECAST TO WEAKEN AS IT
MOVES SOUTH THIS MORNING, THOUGH THERE IS ENOUGH MOISTURE AND
INSTABILITY TO PRODUCE SNOW AROUND THE TAHOE BASIN WITH ISOLATED TO
SCATTERED SHOWERS ACROSS WESTERN NEVADA. THERE COULD BE AN INCH OR
TWO OF ACCUMULATION ON TARMACS/RUNWAYS AT KTRK AND KTVL TODAY. THE
FRONT WILL ALSO KICK UP GUSTS TO NEAR 30KTS THIS MORNING ALONG AND
SOUTH OF KTRK-KRNO-KLOL.

A FEW LIGHT SHOWERS SHOULD BREAK INTO THE VICINITY OF KRNO AND KCXP
BY 17Z, BUT TEMPERATURES MAY WARM ENOUGH TO GET THE SNOW LEVEL OFF
THE NEVADA VALLEY FLOORS. BRONG

&&

.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&

$$

FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)






AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 150 PM CST FRI DEC 19 2014

.SHORT TERM...
259 AM CST

THROUGH SUNDAY...

THE MAIN CONCERNS DURING THE SHORT TERM WILL BE SOME PERIODIC
CHANCES OF VERY LIGHT SNOW OR DRIZZLE THROUGH THE WEEKEND AS SEVERAL
WEAK...AND FAST MOVING MID LEVEL DISTURBANCES SHIFT ACROSS THE AREA.

SURFACE HIGH PRESSURE IS CENTERED ACROSS MUCH OF THE MID AND UPPER
MISSISSIPPI RIVER VALLEY EARLY THIS MORNING. THIS FEATURE IS EXPECTED
TO REMAIN IN CONTROL ACROSS NORTHERN ILLINOIS DURING THE DAY TODAY.
OVERALL...WHICH WILL RESULT IN A VERY LIGHT AND VARIABLE WIND
FIELD ACROSS THE AREA TODAY. AN AREA OF LAKE EFFECT FLURRIES
CONTINUES ACROSS PORTIONS OF THE CHICAGO AREA...AND INTO
NORTHWESTERN INDIANA NEAR LAKE MICHIGAN. MODEL SOUNDINGS INDICATE
JUST DEEP ENOUGH INVERSION HEIGHTS TO SUPPORT ICE IN THE
CLOUDS...AND GIVEN MDW HAS BEEN REPORTING ONLY -SN FOR MOST OF THE
NIGHT IT APPEARS THE THREAT OF FREEZING DRIZZLE WILL BE LOW. ALL
OF THIS ACTIVITY SHOULD WANE ACROSS THE AREA DURING THE MORNING AS
THE WIND FIELD CONTINUES TO WEAKEN OVER SOUTH LAKE MICHIGAN IN
RESPONSE TO THE APPROACHING SURFACE RIDGE OF HIGH PRESSURE.

SURFACE WINDS WILL BEGIN TO SHIFT OUT OF THE SOUTH BY EARLY SATURDAY
MORNING AS THIS SURFACE HIGH BEGINS TO SHIFT EAST OF THE REGION. AS
THIS OCCURS...GUIDANCE IS INSISTENT WITH BRINGING A WEAK UPPER
DISTURBANCE ACROSS NORTHERN ILLINOIS SATURDAY MORNING. THIS WEAK
WAVE IS NOTED IN THE WATER VAPOR IMAGERY CURRENTLY ACROSS
SOUTHEASTERN ALBERTA. MOISTURE APPEARS TO REMAIN LIMITED WITH THIS
WAVE. HOWEVER...I THINK THIS WAVE...AND SOME WEAK ISENTROPIC ASCENT
COULD SQUEEZE OUT A FEW FLURRIES SATURDAY MORNING...SO I HAVE
INCLUDED A SLIGHT CHANCE FOR SUCH IN THE FORECAST.

WARM AIR ADVECTION/ISENTROPIC ASCENT WILL CONTINUE TO INCREASE
ACROSS MUCH OF THE MIDWEST AND GREAT LAKES REGION INTO SUNDAY IN
RESPONSE TO AN INCREASING SOUTHERLY WIND FIELD AHEAD OF A STORM
SYSTEM...WHICH IS EXPECTED TO DEVELOP ACROSS THE PLAINS. THIS COULD
AGAIN RESULT IN A PERIOD OF LIGHT PRECIP ACROSS MAINLY FAR NORTHERN
ILLINOIS VERY LATE SATURDAY NIGHT AND INTO SUNDAY.
OVERALL...CONFIDENCE IS LOW AS TO HOW FAR SOUTH THIS LIGHT PRECIP
WILL BE ABLE TO DEVELOP...BUT GIVEN THE POTENTIAL THAT IF THIS
PRECIP DOES DEVELOP AS FAR SOUTH AS NORTHERN ILLINOIS...THERE COULD
BE A PERIOD OF FREEZING DRIZZLE INTO EARLY SUNDAY MORNING BEFORE
TEMPERATURES JUMP ABOVE FREEZING...I HAVE OPTED TO INCLUDE A SLIGHT
MENTION LATE SATURDAY NIGHT INTO EARLY SUNDAY...MAINLY FOR AREAS
NORTH OF INTERSTATE 90.

KJB

&&

.LONG TERM...
259 AM CST

SUNDAY NIGHT THROUGH THURSDAY...

THE LONG TERM PERIOD WILL BE A PERIOD OF A SIGNIFICANT WEATHER
PATTERN SHIFT ACROSS NORTH AMERICA AND AS SUCH...IT APPEARS LIKELY
THAT THE CENTRAL CONUS WILL BECOME MUCH MORE ACTIVE INTO THE
HOLIDAY WEEK. THE MAIN CONCERNS LOCALLY WITH THIS PATTERN
SHIFT...WILL BE PRECIP TYPES...AND THE ACTUAL EVOLUTION
OF...POTENTIALLY A SIGNIFICANT STORM SYSTEM ACROSS PORTIONS OF THE
GREAT LAKES REGION CHRISTMAS EVE.

UNFORTUNATELY...THE DETAILS OF THIS STORM SYSTEM THIS FAR OUT ARE
STILL LARGELY UNCERTAIN...AS LARGE SCALE PATTERN SHIFTS SUCH AS THIS
TYPICAL RESULT IN LOWER PREDICTABILITY...ESPECIALLY WITH REGARDS TO
THE TRACK AND ACTUAL STRENGTH OF A DEVELOPING STORM SYSTEM. WHAT
APPEARS TO BE LIKELY...HOWEVER...IS FOR A PERIOD OF RAIN ACROSS THE
AREA LATE MONDAY AND MONDAY NIGHT AS WHAT APPEARS TO BE THE INITIAL
STORM SYSTEM...BEGINS TO SHIFT A WARM FRONT ACROSS NORTHERN
ILLINOIS. GIVEN THE WARM SECTOR PLACEMENT OF MY AREA...PRECIP TYPE
LOOKS TO BE LIQUID...WITH SURFACE TEMPERATURES LIKELY TO REMAIN
ABOVE FREEZING MONDAY NIGHT WITH CONTINUED SOUTHERN FLOW.

THE MAIN UNCERTAINTIES COME INTO PLAY BY CHRISTMAS EVE...AS MODEL
GUIDANCE CONTINUES TO ADVERTISE A SIGNIFICANT AMPLIFICATION TO THE
UPPER LEVEL PATTERN ACROSS THE EASTERN PACIFIC AND NORTH AMERICA. A
STRONG PACIFIC JET (NEAR 40 DEGREES N)...INITIALIZED AT OVER 180 KT
IN THIS EVENINGS MODEL OUTPUT IS FORECAST TO RESULT IN THE BUILDING
OF A POTENT UPPER RIDGE JUST OFF THE CALIFORNIA COAST BY EARLY NEXT
WEEK. TELECONNECTIONS RELATED TO SUCH PATTERN SHIFT CERTAINLY SUPPORT
THE DIGGING OF A SIGNIFICANT TROUGH...AND A GOOD POSSIBILITY OF AN
STORM SYSTEM ACROSS THE CENTRAL CONUS DURING THE UPCOMING HOLIDAY
WEEK. HOWEVER...AS PREVIOUSLY MENTIONED CONFIDENCE IS LOW WITH THE
DETAILS OF HOW AND WHERE EXACTLY THIS STORM MAY TRACK. THIS IS A
PERIOD WORTH WATCHING THOUGH...AS AT LEAST SOME SNOW AND POSSIBLY
STRONG NORTHWEST WINDS COULD BE IN STORE.

KJB

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 20Z...

* MVFR CIGS.

BMD

//DISCUSSION...UPDATED 18Z...

RELATIVELY UNCHANGING CONDITIONS ARE EXPECTED TO CONTINUE THROUGH
THE TAF PERIOD WITH PRIMARILY MVFR CIGS AND LIGHT WINDS. WINDS THIS
AFTERNOON ARE GENERALLY 5 KT OR LESS AND OUT OF THE NORTH OR
NORTHWEST...BUT WILL LIKELY BECOME MORE VARIABLE AND POSSIBLY CALM
FOR A PERIOD THIS EVENING AND OVERNIGHT...BEFORE SOUTHERLY WINDS
START TO CREEP IN BEHIND THE HIGH TOMORROW. WHILE A FEW BREAKS IN
THE CLOUDS MAY DEVELOP...EXPECT MVFR CIGS TO GENERALLY REMAIN LOCKED
IN UNDER A STRONG INVERSION WITH SOME LOWERING OVERNIGHT.

BMD

//ORD AND MDW CONFIDENCE...UPDATED 20Z...

* MEDIUM IN CIGS.
* HIGH IN REMAINING FORECAST ELEMENTS.

BMD

//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...

SATURDAY NIGHT...MVFR LIKELY. LIGHT SOUTH WINDS.

SUNDAY...SLGT CHANCE FLURRIES/FREEZING DRIZZLE EARLY. MVFR LIKELY.
SOUTH-SOUTHEAST WINDS.

MONDAY AND TUESDAY...CHANCE OF RAIN...ESPECIALLY MONDAY NIGHT. MVFR
LIKELY. SOUTHEAST WINDS MONDAY BECOMING SOUTHWEST TUESDAY.

WEDNESDAY...CHANCE OF SNOW. MVFR POSSIBLE. GUSTY WEST WINDS.

THURSDAY...DRY. VFR.

RATZER

&&

.MARINE...
156 AM CST

MAIN MARINE CONCERNS THIS MORNING ARE A PERIOD OF STRENGTHENING
SOUTH-SOUTHEAST WINDS LATE SUNDAY THROUGH MONDAY NIGHT...THEN THE
POTENTIAL FOR WEST GALES LATE WEDNESDAY INTO THURSDAY.

FAIRLY QUIET STRETCH OF WEATHER ACROSS LAKE MICHIGAN TODAY THROUGH
SATURDAY AS A LARGE AREA OF WEAK HIGH PRESSURE DRIFTS SLOWLY EAST
ACROSS THE REGION. LIGHT NORTH WINDS TODAY WILL BECOME SOMEWHAT
LIGHT/VARIABLE...BEFORE BECOMING LIGHT SOUTH ON SATURDAY AS THE
SURFACE RIDGE AXIS PASSES TO THE EAST. SOUTHERLY WINDS WILL THEN
BEGIN TO INCREASE SATURDAY NIGHT AND MORE SO SUNDAY...AS LOW
PRESSURE DEVELOPS IN THE LEE OF THE NORTHERN ROCKIES AND THE
GRADIENT BEGINS TO TIGHTEN ACROSS THE PLAINS AND UPPER MIDWEST.
MEDIUM RANGE FORECAST MODELS ARE IN GENERAL AGREEMENT IN DEVELOPING
A SUB-1000 MB SURFACE LOW ACROSS IOWA OR SOUTHERN MINNESOTA BY
MIDDAY MONDAY...WHICH WOULD LEAD TO SOUTH-SOUTHEAST WINDS IN THE
20-25 KT RANGE THROUGH MONDAY BEFORE OCCLUDING AND WEAKENING AS THE
LOW MOVES ACROSS WISCONSIN AND LAKE MICHIGAN ON TUESDAY.

HOWEVER...VARIOUS MODEL AND MODEL ENSEMBLE MEMBERS THEN DEVELOP A
SECOND LOW SOUTH OF THE LAKES ALONG THE TRAILING COLD FRONT TUESDAY
NIGHT...WHICH WOULD LIFT NORTH AND COMBINE WITH THE FILLING GREAT
LAKES LOW...DEEPENING RAPIDLY WEDNESDAY AND WEDNESDAY NIGHT OVER THE
EASTERN LAKES. THIS SCENARIO WOULD LEAD TO QUICKLY INCREASING
WESTERLY WINDS ACROSS LAKE MICHIGAN...QUITE POSSIBLY WEST GALES...
LATE WEDNESDAY INTO THURSDAY/CHRISTMAS DAY AS THE LOW PULLS AWAY TO
THE NORTHEAST.

RATZER

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$

VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO





Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1158 AM CST Fri Dec 19 2014

.UPDATE...
ISSUED AT 1035 AM CST FRI DEC 19 2014

16z/10am visible satellite imagery shows sunny skies across most
of central Illinois, with low clouds bracketing the KILX CWA to
the west, north, and east. This large area of clearing developed
directly beneath a ridge of high pressure last night and has
persisted through this morning. Main short-term challenge will be
whether or not skies will become overcast again today. Satellite
loops over the past couple of hours are showing very little
change, with even some erosion of the cloud cover across the far
SW CWA around Jacksonville. With surface high remaining in place
and very weak low-level winds, do not see clouds currently in
place across Iowa/Missouri returning very quickly. NAM forecast
soundings generally remain dry until later in the afternoon when
low clouds slowly begin to encroach from the west and high/thin
cirrus stream northeastward from a storm system tracking across
the southern Plains. End result will be a partly to mostly sunny
day across central Illinois with afternoon high temperatures
reaching the lower to middle 30s.

&&

.SHORT TERM...(Today)
ISSUED AT 459 AM CST FRI DEC 19 2014

High pressure is expected to hold over central Illinois through
today with the next southern stream shortwave, currently over south
central Texas early this morning, forecast to track well south of
our area. 2am satellite data and surface observations showing an
area of clear skies extending from just northwest of Peoria
southeast thru Champaign and Decatur. Short range models suggest
this area will gradually fill back in with clouds as the day wears
on. Forecast soundings from the HRRR and Rapid Refresh models also
support this idea thru the day with the last few satellite frames
off the IR loop indicating the clouds over far west central IL were
starting to shift more to the east. Forecast soundings across
central IL today support afternoon temperatures in the low to mid
30s with another day with very little wind, something that is a bit
on the rare side for December across our area.

&&

.LONG TERM...(Tonight through Thursday)
ISSUED AT 459 AM CST FRI DEC 19 2014

Main focus remains with active pattern setting up for the upcoming
holiday week.

Powerful jet of 120-160 knots at 300 mb will be coming into the
Pacific Northwest later this weekend before diving toward the
southern Plains, helping to carve out a deep trough over the central
U.S. The GFS and ECMWF models are in good agreement with development
of a closed low over eastern South Dakota by midday Monday, with
some minor disagreements as to the amount of wobbling of this low as
it drifts toward the east. The ECMWF brings the center as far south
as Springfield by Wednesday morning, while the GFS and Canadian
models are centered across Wisconsin.

Precipitation shield with this system expected to start spreading
into the Illinois River valley by late Monday morning, then eastward
across the state during the day. The GFS is more prominent with a
dry slot punching in already by late evening, while the ECMWF
lingers the rain into Tuesday morning. Leaned more towards the
slower ECMWF solution and increased rain chances to around 60%
Monday night north of I-74 and east of I-57. Forecast soundings are
well above freezing up to around 850 mb, so have removed any mixed
precip wording for Monday night. Some mixture possible northwest of
the Illinois River on Tuesday, although a loss of ice crystals aloft
with the dry slot may mitigate this.

As we head toward Christmas Eve, amount of wrap-around precipitation
is a concern. The ECMWF rapidly intensifies the surface cyclone to
our east, with central pressure down to around 978 mb midday near
Cleveland. This solution brings periodic snow showers southeast into
our area in the strong northwest flow. The much weaker GFS has some
flurries lingering through the day, with less windy conditions. Have
kept precipitation chances across the east during the day on the
edge of the ECMWF`s dry slot, but kept only slight chances elsewhere
for now. Snowfall amounts still appear to be on the light side, but
holiday travel will still not be pleasant with the snow and the
winds. Christmas Day itself appears dry.

&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
ISSUED AT 1158 AM CST FRI DEC 19 2014

Latest satellite imagery continues to indicate mostly clear skies
across much of central Illinois late this morning, with VFR ceilings
persisting at only KSPI. Further west, MVFR/IFR ceilings blanket
Iowa/Missouri. With high pressure directly overhead, low-level
winds are quite light and will remain light until the high begins
to shift off to the east later tonight into Saturday. At that
time, return flow on the back side of the slowly departing high
will allow lower clouds to spill back into the area from the W/SW.
Have therefore gone with VFR conditions across the board this
afternoon/evening, followed by a gradual return of MVFR ceilings
overnight into Saturday morning. Have lowered ceilings to around
2500ft and introduced restricted visbys down to 4sm between 13z
and 16z accordingly.

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...Barnes
SHORT TERM...Smith
LONG TERM...Geelhart
AVIATION...Barnes








AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 1137 AM CST FRI DEC 19 2014

.SHORT TERM...
259 AM CST

THROUGH SUNDAY...

THE MAIN CONCERNS DURING THE SHORT TERM WILL BE SOME PERIODIC
CHANCES OF VERY LIGHT SNOW OR DRIZZLE THROUGH THE WEEKEND AS SEVERAL
WEAK...AND FAST MOVING MID LEVEL DISTURBANCES SHIFT ACROSS THE AREA.

SURFACE HIGH PRESSURE IS CENTERED ACROSS MUCH OF THE MID AND UPPER
MISSISSIPPI RIVER VALLEY EARLY THIS MORNING. THIS FEATURE IS EXPECTED
TO REMAIN IN CONTROL ACROSS NORTHERN ILLINOIS DURING THE DAY TODAY.
OVERALL...WHICH WILL RESULT IN A VERY LIGHT AND VARIABLE WIND
FIELD ACROSS THE AREA TODAY. AN AREA OF LAKE EFFECT FLURRIES
CONTINUES ACROSS PORTIONS OF THE CHICAGO AREA...AND INTO
NORTHWESTERN INDIANA NEAR LAKE MICHIGAN. MODEL SOUNDINGS INDICATE
JUST DEEP ENOUGH INVERSION HEIGHTS TO SUPPORT ICE IN THE
CLOUDS...AND GIVEN MDW HAS BEEN REPORTING ONLY -SN FOR MOST OF THE
NIGHT IT APPEARS THE THREAT OF FREEZING DRIZZLE WILL BE LOW. ALL
OF THIS ACTIVITY SHOULD WANE ACROSS THE AREA DURING THE MORNING AS
THE WIND FIELD CONTINUES TO WEAKEN OVER SOUTH LAKE MICHIGAN IN
RESPONSE TO THE APPROACHING SURFACE RIDGE OF HIGH PRESSURE.

SURFACE WINDS WILL BEGIN TO SHIFT OUT OF THE SOUTH BY EARLY SATURDAY
MORNING AS THIS SURFACE HIGH BEGINS TO SHIFT EAST OF THE REGION. AS
THIS OCCURS...GUIDANCE IS INSISTENT WITH BRINGING A WEAK UPPER
DISTURBANCE ACROSS NORTHERN ILLINOIS SATURDAY MORNING. THIS WEAK
WAVE IS NOTED IN THE WATER VAPOR IMAGERY CURRENTLY ACROSS
SOUTHEASTERN ALBERTA. MOISTURE APPEARS TO REMAIN LIMITED WITH THIS
WAVE. HOWEVER...I THINK THIS WAVE...AND SOME WEAK ISENTROPIC ASCENT
COULD SQUEEZE OUT A FEW FLURRIES SATURDAY MORNING...SO I HAVE
INCLUDED A SLIGHT CHANCE FOR SUCH IN THE FORECAST.

WARM AIR ADVECTION/ISENTROPIC ASCENT WILL CONTINUE TO INCREASE
ACROSS MUCH OF THE MIDWEST AND GREAT LAKES REGION INTO SUNDAY IN
RESPONSE TO AN INCREASING SOUTHERLY WIND FIELD AHEAD OF A STORM
SYSTEM...WHICH IS EXPECTED TO DEVELOP ACROSS THE PLAINS. THIS COULD
AGAIN RESULT IN A PERIOD OF LIGHT PRECIP ACROSS MAINLY FAR NORTHERN
ILLINOIS VERY LATE SATURDAY NIGHT AND INTO SUNDAY.
OVERALL...CONFIDENCE IS LOW AS TO HOW FAR SOUTH THIS LIGHT PRECIP
WILL BE ABLE TO DEVELOP...BUT GIVEN THE POTENTIAL THAT IF THIS
PRECIP DOES DEVELOP AS FAR SOUTH AS NORTHERN ILLINOIS...THERE COULD
BE A PERIOD OF FREEZING DRIZZLE INTO EARLY SUNDAY MORNING BEFORE
TEMPERATURES JUMP ABOVE FREEZING...I HAVE OPTED TO INCLUDE A SLIGHT
MENTION LATE SATURDAY NIGHT INTO EARLY SUNDAY...MAINLY FOR AREAS
NORTH OF INTERSTATE 90.

KJB

&&

.LONG TERM...
259 AM CST

SUNDAY NIGHT THROUGH THURSDAY...

THE LONG TERM PERIOD WILL BE A PERIOD OF A SIGNIFICANT WEATHER
PATTERN SHIFT ACROSS NORTH AMERICA AND AS SUCH...IT APPEARS LIKELY
THAT THE CENTRAL CONUS WILL BECOME MUCH MORE ACTIVE INTO THE
HOLIDAY WEEK. THE MAIN CONCERNS LOCALLY WITH THIS PATTERN
SHIFT...WILL BE PRECIP TYPES...AND THE ACTUAL EVOLUTION
OF...POTENTIALLY A SIGNIFICANT STORM SYSTEM ACROSS PORTIONS OF THE
GREAT LAKES REGION CHRISTMAS EVE.

UNFORTUNATELY...THE DETAILS OF THIS STORM SYSTEM THIS FAR OUT ARE
STILL LARGELY UNCERTAIN...AS LARGE SCALE PATTERN SHIFTS SUCH AS THIS
TYPICAL RESULT IN LOWER PREDICTABILITY...ESPECIALLY WITH REGARDS TO
THE TRACK AND ACTUAL STRENGTH OF A DEVELOPING STORM SYSTEM. WHAT
APPEARS TO BE LIKELY...HOWEVER...IS FOR A PERIOD OF RAIN ACROSS THE
AREA LATE MONDAY AND MONDAY NIGHT AS WHAT APPEARS TO BE THE INITIAL
STORM SYSTEM...BEGINS TO SHIFT A WARM FRONT ACROSS NORTHERN
ILLINOIS. GIVEN THE WARM SECTOR PLACEMENT OF MY AREA...PRECIP TYPE
LOOKS TO BE LIQUID...WITH SURFACE TEMPERATURES LIKELY TO REMAIN
ABOVE FREEZING MONDAY NIGHT WITH CONTINUED SOUTHERN FLOW.

THE MAIN UNCERTAINTIES COME INTO PLAY BY CHRISTMAS EVE...AS MODEL
GUIDANCE CONTINUES TO ADVERTISE A SIGNIFICANT AMPLIFICATION TO THE
UPPER LEVEL PATTERN ACROSS THE EASTERN PACIFIC AND NORTH AMERICA. A
STRONG PACIFIC JET (NEAR 40 DEGREES N)...INITIALIZED AT OVER 180 KT
IN THIS EVENINGS MODEL OUTPUT IS FORECAST TO RESULT IN THE BUILDING
OF A POTENT UPPER RIDGE JUST OFF THE CALIFORNIA COAST BY EARLY NEXT
WEEK. TELECONNECTIONS RELATED TO SUCH PATTERN SHIFT CERTAINLY SUPPORT
THE DIGGING OF A SIGNIFICANT TROUGH...AND A GOOD POSSIBILITY OF AN
STORM SYSTEM ACROSS THE CENTRAL CONUS DURING THE UPCOMING HOLIDAY
WEEK. HOWEVER...AS PREVIOUSLY MENTIONED CONFIDENCE IS LOW WITH THE
DETAILS OF HOW AND WHERE EXACTLY THIS STORM MAY TRACK. THIS IS A
PERIOD WORTH WATCHING THOUGH...AS AT LEAST SOME SNOW AND POSSIBLY
STRONG NORTHWEST WINDS COULD BE IN STORE.

KJB

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 18Z...

* MVFR CIGS.

BMD

//DISCUSSION...UPDATED 18Z...

RELATIVELY UNCHANGING CONDITIONS ARE EXPECTED TO CONTINUE THROUGH
THE TAF PERIOD WITH PRIMARILY MVFR CIGS AND LIGHT WINDS. WINDS THIS
AFTERNOON ARE GENERALLY 5 KT OR LESS AND OUT OF THE NORTH OR
NORTHWEST...BUT WILL LIKELY BECOME MORE VARIABLE AND POSSIBLY CALM
FOR A PERIOD THIS EVENING AND OVERNIGHT...BEFORE SOUTHERLY WINDS
START TO CREEP IN BEHIND THE HIGH TOMORROW. WHILE A FEW BREAKS IN
THE CLOUDS MAY DEVELOP...EXPECT MVFR CIGS TO GENERALLY REMAIN LOCKED
IN UNDER A STRONG INVERSION WITH SOME LOWERING OVERNIGHT.

BMD


//ORD AND MDW CONFIDENCE...UPDATED 18Z...

* MEDIUM IN CIGS.
* HIGH IN REMAINING FORECAST ELEMENTS.

BMD

//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...

SATURDAY NIGHT...MVFR LIKELY. LIGHT SOUTH WINDS.

SUNDAY...SLGT CHANCE FLURRIES/FREEZING DRIZZLE EARLY. MVFR LIKELY.
SOUTH-SOUTHEAST WINDS.

MONDAY AND TUESDAY...CHANCE OF RAIN...ESPECIALLY MONDAY NIGHT. MVFR
LIKELY. SOUTHEAST WINDS MONDAY BECOMING SOUTHWEST TUESDAY.

WEDNESDAY...CHANCE OF SNOW. MVFR POSSIBLE. GUSTY WEST WINDS.

THURSDAY...DRY. VFR.

RATZER

&&

.MARINE...
156 AM CST

MAIN MARINE CONCERNS THIS MORNING ARE A PERIOD OF STRENGTHENING
SOUTH-SOUTHEAST WINDS LATE SUNDAY THROUGH MONDAY NIGHT...THEN THE
POTENTIAL FOR WEST GALES LATE WEDNESDAY INTO THURSDAY.

FAIRLY QUIET STRETCH OF WEATHER ACROSS LAKE MICHIGAN TODAY THROUGH
SATURDAY AS A LARGE AREA OF WEAK HIGH PRESSURE DRIFTS SLOWLY EAST
ACROSS THE REGION. LIGHT NORTH WINDS TODAY WILL BECOME SOMEWHAT
LIGHT/VARIABLE...BEFORE BECOMING LIGHT SOUTH ON SATURDAY AS THE
SURFACE RIDGE AXIS PASSES TO THE EAST. SOUTHERLY WINDS WILL THEN
BEGIN TO INCREASE SATURDAY NIGHT AND MORE SO SUNDAY...AS LOW
PRESSURE DEVELOPS IN THE LEE OF THE NORTHERN ROCKIES AND THE
GRADIENT BEGINS TO TIGHTEN ACROSS THE PLAINS AND UPPER MIDWEST.
MEDIUM RANGE FORECAST MODELS ARE IN GENERAL AGREEMENT IN DEVELOPING
A SUB-1000 MB SURFACE LOW ACROSS IOWA OR SOUTHERN MINNESOTA BY
MIDDAY MONDAY...WHICH WOULD LEAD TO SOUTH-SOUTHEAST WINDS IN THE
20-25 KT RANGE THROUGH MONDAY BEFORE OCCLUDING AND WEAKENING AS THE
LOW MOVES ACROSS WISCONSIN AND LAKE MICHIGAN ON TUESDAY.

HOWEVER...VARIOUS MODEL AND MODEL ENSEMBLE MEMBERS THEN DEVELOP A
SECOND LOW SOUTH OF THE LAKES ALONG THE TRAILING COLD FRONT TUESDAY
NIGHT...WHICH WOULD LIFT NORTH AND COMBINE WITH THE FILLING GREAT
LAKES LOW...DEEPENING RAPIDLY WEDNESDAY AND WEDNESDAY NIGHT OVER THE
EASTERN LAKES. THIS SCENARIO WOULD LEAD TO QUICKLY INCREASING
WESTERLY WINDS ACROSS LAKE MICHIGAN...QUITE POSSIBLY WEST GALES...
LATE WEDNESDAY INTO THURSDAY/CHRISTMAS DAY AS THE LOW PULLS AWAY TO
THE NORTHEAST.

RATZER

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$

VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO






Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1035 AM CST Fri Dec 19 2014

.UPDATE...
ISSUED AT 1035 AM CST FRI DEC 19 2014

16z/10am visible satellite imagery shows sunny skies across most
of central Illinois, with low clouds bracketing the KILX CWA to
the west, north, and east. This large area of clearing developed
directly beneath a ridge of high pressure last night and has
persisted through this morning. Main short-term challenge will be
whether or not skies will become overcast again today. Satellite
loops over the past couple of hours are showing very little
change, with even some erosion of the cloud cover across the far
SW CWA around Jacksonville. With surface high remaining in place
and very weak low-level winds, do not see clouds currently in
place across Iowa/Missouri returning very quickly. NAM forecast
soundings generally remain dry until later in the afternoon when
low clouds slowly begin to encroach from the west and high/thin
cirrus stream northeastward from a storm system tracking across
the southern Plains. End result will be a partly to mostly sunny
day across central Illinois with afternoon high temperatures
reaching the lower to middle 30s.

&&

.SHORT TERM...(Today)
ISSUED AT 459 AM CST FRI DEC 19 2014

High pressure is expected to hold over central Illinois through
today with the next southern stream shortwave, currently over south
central Texas early this morning, forecast to track well south of
our area. 2am satellite data and surface observations showing an
area of clear skies extending from just northwest of Peoria
southeast thru Champaign and Decatur. Short range models suggest
this area will gradually fill back in with clouds as the day wears
on. Forecast soundings from the HRRR and Rapid Refresh models also
support this idea thru the day with the last few satellite frames
off the IR loop indicating the clouds over far west central IL were
starting to shift more to the east. Forecast soundings across
central IL today support afternoon temperatures in the low to mid
30s with another day with very little wind, something that is a bit
on the rare side for December across our area.

&&

.LONG TERM...(Tonight through Thursday)
ISSUED AT 459 AM CST FRI DEC 19 2014

Main focus remains with active pattern setting up for the upcoming
holiday week.

Powerful jet of 120-160 knots at 300 mb will be coming into the
Pacific Northwest later this weekend before diving toward the
southern Plains, helping to carve out a deep trough over the central
U.S. The GFS and ECMWF models are in good agreement with development
of a closed low over eastern South Dakota by midday Monday, with
some minor disagreements as to the amount of wobbling of this low as
it drifts toward the east. The ECMWF brings the center as far south
as Springfield by Wednesday morning, while the GFS and Canadian
models are centered across Wisconsin.

Precipitation shield with this system expected to start spreading
into the Illinois River valley by late Monday morning, then eastward
across the state during the day. The GFS is more prominent with a
dry slot punching in already by late evening, while the ECMWF
lingers the rain into Tuesday morning. Leaned more towards the
slower ECMWF solution and increased rain chances to around 60%
Monday night north of I-74 and east of I-57. Forecast soundings are
well above freezing up to around 850 mb, so have removed any mixed
precip wording for Monday night. Some mixture possible northwest of
the Illinois River on Tuesday, although a loss of ice crystals aloft
with the dry slot may mitigate this.

As we head toward Christmas Eve, amount of wrap-around precipitation
is a concern. The ECMWF rapidly intensifies the surface cyclone to
our east, with central pressure down to around 978 mb midday near
Cleveland. This solution brings periodic snow showers southeast into
our area in the strong northwest flow. The much weaker GFS has some
flurries lingering through the day, with less windy conditions. Have
kept precipitation chances across the east during the day on the
edge of the ECMWF`s dry slot, but kept only slight chances elsewhere
for now. Snowfall amounts still appear to be on the light side, but
holiday travel will still not be pleasant with the snow and the
winds. Christmas Day itself appears dry.

&&

.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 525 AM CST FRI DEC 19 2014

High pressure centered from northeast Iowa southeast thru central
Illinois has helped to scour out some of the MVFR clouds that
have dominated our area over the past 24 hours, especially along
the ridge axis early this morning. Satellite data indicates the
clear area extended from Moline southeast thru Peoria, Bloomington
and Champaign with MVFR cigs to the north and south. Forecast
soundings continue to suggest areas that were experiencing the
clear skies this morning should see the low VFR and even some MVFR
cigs move back in by later this morning into the afternoon hours.
Confidence on timing and extent of the lower VFR and MVFR cigs
across the area today is rather low, so will trend with more
clouds across the north and east by later this morning into the
afternoon hours but keep it mostly low VFR at this time. Surface
winds will once again be a non- factor today as our area will be
under the high pressure system so will continue with a light and
variable wind over most of the area into tonight.


&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...Barnes
SHORT TERM...Smith
LONG TERM...Geelhart
AVIATION...Smith







AREA FORECAST DISCUSSION

NWS TOPEKA KS

 1202 PM CST Fri Dec 19 2014

...Update to aviation forecast discussion...

.SHORT TERM...(Today and Tonight)
Issued at 246 AM CST FRI DEC 19 2014

08Z water vapor imagery indicated there were a couple waves within a
somewhat slow split flow over the plains. The stronger wave was
lifting through the southern plains with some decent lightning noted
in eastern TX. A second weaker wave was noted over southeastern MT.
At the surface a high pressure system centered over the central and
upper MS river valley was nosing into eastern KS with a ridge axis
bisecting the forecast area.

For today and tonight, the better forcing from the shortwaves looks
to only glance the forecast area. Forecast soundings from the
RAP/NAM/GFS indicated a decent amount of dry air in the mid levels
and prog a westerly wind at 850 and above to continue advecting dry
air in from the west. So with the weak forcing unlikely to overcome
the dry air in mid levels, have maintained a dry forecast through
tonight. Really the main forecast challenge is the boundary layer
moisture and pesky stratus. All the models fall to mix out the low
level inversion and the boundary layer moisture. This seems to make
some since with the expansive stratus deck already in place and snow
cover limiting any insolation to warm surface temps. Therefore have
leaned towards an overcast sky through tonight. Isentropic surfaces
show only weak if any isentropic upglide and appear to focus this
mainly across MO, so concerns for drizzle are minimal today as well.
About the only uncertainty with the forecast is the NAM`s tendency
to over due the impact of the snow cover and keeping the boundary
layer to cool for to long. However with the GFS and RAP showing
similar solutions, think the low clouds scattering out is a low
chance occurrence. Highs today are expected to be in the mid 30s
with no real low level warm air advection and clouds holding on
strong. For tonight have kept skies cloudy, but if for some reason
we were to clear out, fog would become more likely. I don`t have a
lot of confidence in this happening. Nevertheless have added a
mention of patchy fog after midnight due to forecast soundings
showing the potential for some fog, especially across north central
KS. Lows tonight are expected to range from the mid 20 to around 30.

.LONG TERM...(Saturday through Thursday)
Issued at 246 AM CST FRI DEC 19 2014

Patchy fog is expected to linger through mid morning Saturday before
lifting to mostly cloudy stratus. A developing surface trough over
eastern CO will pick up winds around 10 mph, attempting to mix out
the stratus in the lower levels. Best chances for seeing peeks of
sunshine lie across central KS, with much of the CWA remaining
cloudy. Despite the warmer temps from guidance, believe the
lingering snow cover holds highs a few degrees cooler in north
central and far northeast KS where upper 30s are common. Areas with
little to no snow cover may reach the lower to middle 40s. Surface
trough begins to deepen on Sunday in response to the upper shortwave
trough coming onshore from the Pacific NW. Southwesterly winds
increase around 15 mph through the afternoon. A weaker lead trough
progresses over the northern plains Sunday morning, bringing a
chance for light drizzle. Freezing precip should not be a concern as
guidance is trending warmer near 40 degrees for morning lows.
Precip chances increase Sunday evening into Monday as the system
shifts east over the northern plains. Discrepancies remain on
guidance as the latest ECMWF is less amplified and impacting more
of the eastern CWA, similar to the GEM. In addition, the GFS is
more amplified from an upper jet streak rounding the southern edge
of the wave. Given this and the amount of saturation is relative
compared to previous systems, will continue with 30-40 pops until
more consistency is seen between runs. Bulk of the QPF is rain on
Monday as highs peak in the upper 40s. The freezing temps slide in
behind the departing wave where a rain and snow mix is possible
Monday evening. No accumulation is expected at this time.

An anomalous upper ridge builds eastward into the region Tuesday and
Wednesday giving the area a chance to clear out the stratus clouds.
Modified airmass in the wake of the system will only drop highs into
the low 40s for highs and lows in the upper 20s and low 30s. In
terms of Christmas Day, much uncertainty exists with the timing and
track of the next upper trough. Latest runs are trending slower with
the system, GFS being more progressive and impacting mainly north
central areas. Meanwhile the ECMWF is slower and places our area in
the dry slot. While confidence is below average, will maintain
forecast consistency with slight chances for a rain and snow mix.

&&

.AVIATION...(For the 18Z TAFs through 18Z Saturday Afternoon)
Issued at 1146 AM CST FRI DEC 19 2014

IFR conditions will last through most the next 24 hours. There may
be a brief period where ceilings will rise to 1000 to 1400 feet
this afternoon. After 02Z SAT the stratus will lower to 600 to 900
feet. visibilites will rise to 6 to 8SM this afternoon but drop to
2 to 4SM after 02Z SAT.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Gargan






AREA FORECAST DISCUSSION

NWS GOODLAND KS

 1032 AM MST FRI DEC 19 2014

.SHORT TERM...(THIS MORNING THROUGH SUNDAY NIGHT)
ISSUED AT 233 AM MST FRI DEC 19 2014

EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW SHORTWAVE
TROUGH OVER OK PANHANDLE WITH SHORTWAVE RIDGE OVER THE TREAT BASIN
BUILDING EAST TOWARDS THE CENTRAL ROCKIES. AT THE SURFACE...LOW
PRESSURE REMAINS IN PLACE FROM THE NORTHERN PLAINS AND ACROSS
EASTERN COLORADO. HIGH PRESSURE IS GENERALLY IN PLACES ACROSS MUCH
OF THE CWA...WITH LOW PRESSURE BEGINNING TO BUILD IN FROM THE WEST.

EARLY THIS MORNING...AXIS OF DENSE FOG DEVELOPED LATE LAST NIGHT
GENERALLY ALONG HWY 25 AND HWY 83 CORRIDOR BEHIND STRATUS DECK TO
THE EAST. WEST OF THIS...BL HAS BEEN TOO DRY FOR DENSE FOG
DEVELOPMENT...THOUGH WITH NEARBY HIGH PRESSURE/LIGHT WINDS/CLEAR
SKIES PATCHY FOG WILL BE POSSIBLE THIS MORNING. RAP/HRRR BOTH HAVE
GOOD REFLECTION OF THE SPOTTY NATURE OF THE FOG OVER OUR CWA...AND
GENERALLY KEEP MAIN AXIS OF DENSE FOG WHERE IT IS...IMPROVING
CONDITIONS AROUND 12-13Z. DUE TO THE LOCALIZED NATURE OF THE
DENSE FOG AND GUIDANCE TRENDING AWAY FROM WIDESPREAD COVERAGE I
DECIDED TO CONTINUE WITH HANDLING THIS EVENT WITH SPS.

TODAY...ANY FOG/STRATUS SHOULD CLEAR BY MIDDAY AS SURFACE LOW SHIFTS
EAST TO THE KS/CO BORDER. THIS WILL SUPPORT TEMPS MODERATING TO THE
40S/NEAR 50 OVER MUCH OF THE CWA (COOLER IN YUMA COUNTY WHERE SNOW
PACK LINGERS).

TONIGHT-WE MAY SEE FOG REDEVELOP ACROSS NORTH CENTRAL KS...WHICH
COULD IMPACT OUR EASTERN CWA. THOUGH NAM/SREF HAVE A PRETTY GOOD
SIGNAL FOR THIS...AS LOW SHIFTS EAST AIR MASS WILL BE CHANGING WITH
LOWER BL MOISTURE PRESENT AND IM NOT AS SURE CURRENT MODEL
COVERAGE/DEPICTION IS REALISTIC. I ADDED PATCHY FREEZING FOG IN OUR
EAST AHEAD OF MAIN SURFACE TROUGH TO COVER POTENTIAL.

SATURDAY-SUNDAY...SHORTWAVE RIDGE WILL TRANSITION EASTWARD ACROSS
THE PLAINS SATURDAY/SATURDAY NIGHT WITH A TROUGH REDEVELOPING OVER
THE NORTHERN PLAINS BY SUNDAY NIGHT. AHEAD OF THIS DEVELOPING UPPER
TROUGH...SURFACE TROUGHING AND INCREASING WAA WILL SUPPORT
INCREASING TEMPS TO WELL ABOVE NORMAL. DEPENDING ON MIXING (WHICH
COULD BE LIMITED BY CLOUDS)...HIGHS BY SUNDAY SHOULD BE IN MIDDLE
50S WITH DECREASING IMPACT FROM SNOW PACK IN THE NORTHWEST AS IT
CONTINUES TO DEGRADE OVER THE NEXT FEW DAYS. I COULD ACTUALLY SEE
SOME LOCATIONS APPROACH THE UPPER 50S SUNDAY BASED ON CURRENT
925/850 MB TEMPS.

SUNDAY NIGHT...LOBES OF MID LEVEL VORTICITY COMBINED WITH INCREASING
FRONTOGENETIC FORCING COULD SUPPORT SEVERAL BANDS OF LIGHT
PRECIPITATION MOVING INTO OUR CWA BY SUNDAY NIGHT. MODELS ARE
SHOWING A GOOD DRY LAYER THAT ANY PRECIP WOULD HAVE TO SATURATE
THROUGH. TEMP PROFILES GENERALLY SUPPORT RAIN...WITH SATURATION TO
WET BULB TEMPS NEAR A RAIN OR RAIN/SNOW MIX LATE SUNDAY NIGHT. DUE
TO UNCERTAINTY OF MEASURABLE DUE TO DRY LAYER AND POSITION OF
THESE BANDS...I KEPT POP MENTION LIMITED TO SLIGHT CHANCE.

.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 233 AM MST FRI DEC 19 2014

AN UPPER LEVEL TROUGH WILL MOVE THROUGH THE CENTRAL PLAINS REGION
MONDAY...BRINGING CHANCES FOR RAIN AND SNOW SHOWERS.  BASED ON THE
LOWER LEVEL TEMPERATURE FIELD...CRITICAL THICKNESSES AND WET BULB
ZERO HEIGHTS...EXPECTING NORTHWEST PORTIONS OF THE FORECAST AREA TO
START AS A RAIN/SNOW MIX.  OTHERWISE...ALL OTHER AREAS WILL RECEIVE
RAIN MONDAY MORNING.  ALTHOUGH THERE IS STRONG NORTHWEST FLOW ALOFT
WITH COOLER TEMPERATURES BEING ADVECTED INTO THE AREA...SURFACE
TEMPERATURES WILL WARM INTO THE MID TO UPPER 40S IN THE AFTERNOON.
THIS SURFACE WARMING WILL ALLOW RAIN TO BE THE PRIMARY PRECIPITATION
TYPE IN THE AFTERNOON.  PRECIPITATION WILL CHANGE BACK TO SNOW AFTER
SUNSET.  ECMWF AND GFS MODELS ARE FORECASTING BETWEEN 1 AND 2 INCHES
OF SNOW...HOWEVER CONFIDENCE IS LOW IN THOSE FORECAST AMOUNTS DUE TO
RUNNING ACCUMULATIONS IN PERIODS OF PHASE CHANGE. THEREFORE...THE
FORECAST REFLECTS TOTAL VALUES LESS THAN AN INCH AT THIS TIME.

A SHORTWAVE RIDGE WILL BUILD INTO THE TRI STATE AREA TUESDAY AND
WEDNESDAY...BRINGING DRY CONDITIONS AND NEAR NORMAL HIGH
TEMPERATURES IN THE LOW TO UPPER 40S.  BLENDED POP FORECAST WAS
HINTING AT PRECIPITATION CHANCES THROUGH THE DAY TUESDAY...BUT
DECIDED TO ELIMINATE POPS DUE TO THE 500 MB AXIS BEING THROUGH THE
FORECAST AREA BY 18Z TUESDAY.

THE NEXT WEATHER SYSTEM TO APPROACH THE REGION WILL COME FROM THE
PACIFIC NORTHWEST CHRISTMAS EVE THROUGH CHRISTMAS DAY.  ALTHOUGH
THIS SYSTEM IS STILL A FEW DAYS OUT...GUIDANCE IS SEEMINGLY SLOWING
THE PROGRESSION OF THE SYSTEM INTO THE AREA TOWARDS A THURSDAY NIGHT
OR FRIDAY ARRIVAL. A GENERAL NORTHWEST FLOW WILL BRING MOISTURE IN
FROM THE PACIFIC NORTHWEST MAINLY ON THE NORTHERN COLD SIDE OF THE
SURFACE LOW...WHICH WILL BRING CHANCES FOR SNOW SHOWERS.  AT THIS
TIME...THINKING A LITTLE OVER AN INCH CAN BE EXPECTED FOR AREAS
NORTH OF INTERSTATE 70.  THIS AMOUNT IS LIKELY TO CHANGE WITH FUTURE
FORECASTS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1025 AM MST FRI DEC 19 2014

VFR CONDITIONS ARE EXPECTED AT KGLD AND KMCK FOR THE NEXT 24
HOURS AS HIGH PRESSURE OVER THE CENTRAL PLAINS SLOWLY DRIFTS EAST
AND A WEAK TROUGH MOVES INTO EASTERN COLORADO SATURDAY AFTERNOON.
THE NAM FORECAST SOUNDING FOR KMCK INDICATES THE POSSIBILITY OF
SOME SHALLOW STRATUS OR LIGHT FOG EARLY SATURDAY MORNING. HOWEVER
DEWPOINT TRENDS ARE DECREASING THROUGH THE NIGHT AS WEST WIND
ADVECTS DRIER AIR INTO THE AREA. PLAN ON LEAVING STRATUS/LIGHT
FOG OUT FOR NOW.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

$$

SHORT TERM...DR
LONG TERM...MK
AVIATION...FS



AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 255 PM EST FRI DEC 19 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM EST FRI DEC 19 2014

A FAIRLY QUIET PATTERN IN THE CENTRAL PART OF THE CONUS...AS THE
SOUTHERN STREAM JET IS SITUATED OVER THE SOUTHERN TIER OF STATES
AND THE SYSTEM THAT BROUGHT SNOW TO THE AREA THIS PAST
TUESDAY/WEDNESDAY IS NOW SPINNING OVER PRINCE EDWARD ISLAND. CLOSER
TO THIS AREA...AN UPPER RIDGE STRETCHES FROM WISCONSIN TO JAMES
BAY...WHILE A UPPER TROUGH IS LOCATED OVER SASKATCHEWAN AND THE
NORTHERN PLAINS. BENEATH THE UPPER RIDGE...1028MB HIGH PRESSURE IS
CENTERED OVER NORTHERN LAKE SUPERIOR WITH A RIDGE STRETCHING SOUTH
THROUGH THE MID MISSISSIPPI VALLEY. THERE IS PLENTY OF DRY AIR ALOFT
ON THE RAP ANALYSIS ASSOCIATED WITH THIS UPPER RIDGE...BUT THE
SUBSIDENCE HAS STRENGTHENED THE INVERSION OVER THE GREAT LAKES AND
UPPER MISSISSIPPI VALLEY REGIONS AND AIDED IN AREAS OF LOW CLOUDS.
THE LARGEST AREA OF LOW CLOUDS COVERS MUCH OF MINNESOTA AND WESTERN
WISCONSIN...WITH THE EASTERN EDGE STRETCHING FROM GRAND MARAIS
MINNESOTA THROUGH IRONWOOD MICHIGAN AND TOWARDS MADISON WISCONSIN.
BUT THERE IS A POCKET OF CLOUDS THAT DEVELOPED OVER SOUTH CENTRAL
LAKE SUPERIOR LATE THIS EVENING (AIDED BY MARGINAL DELTA-T VALUES
FOR LAKE CLOUDS) AND WITH THE LIGHT NORTHERLY FLOW...SHIFTED INTO
THE KEWEENAW AND NORTH CENTRAL U.P.  DEFINITELY HAVE TO GIVE SOME
CREDIT TO THE REGIONAL GEM...WHICH SUPERBLY PICKED UP ON THESE
CLOUDS WITH THE 00Z RUN YESTERDAY. THESE CLOUDS ALLOWED TEMPERATURES
TO QUICKLY RISE AROUND 10 DEGREES AND LOCATIONS UNDER THEM ARE IN
THE MID-UPPER TEENS. ELSEWHERE IN THE U.P. SKIES ARE CLEAR AND WITH
THE LIGHT WINDS...TEMPERATURES HAVE FALLEN INTO THE LOWER SINGLE
DIGITS ABOVE AND BELOW ZERO.

THE UPPER RIDGE AND SURFACE HIGH CURRENTLY OVER THE AREA WILL
SLOWLY SHIFT EAST-SOUTHEAST TODAY AND TONIGHT...ALLOWING THE AREA
TO COME UNDER GREATER INFLUENCE OF THE WEAK UPPER TROUGH. THE LOW
CLOUDS WILL BE THE PRIMARY CONCERN FOR THE FORECAST FOR TODAY. WITH
GENERALLY LIGHT WINDS AND A RELATIVELY LOW SUN ANGLE...GETTING A
HANDLE ON THE LOW CLOUDS OVER THE NORTH CENTRAL AND KEWEENAW IS
DIFFICULT. FOLLOWING 925MB WINDS IN THE MODELS...WOULD EXPECT THEM
TO TRY TO NOSE A LITTLE FARTHER INLAND OVER THE CENTRAL (AND EVEN
THE EASTERN) PART OF THE U.P. TODAY...WHILE THE DEVELOPING LIGHT
SOUTHERLY FLOW WOULD LIKELY PULL DRIER AIR BACK INTO THE KEWEENAW
AND PUSH THOSE CLOUDS NORTH. BUT THAT INCREASING SOUTHERLY FLOW
WILL ALSO PULL THE CLOUDS RIGHT NEAR IRONWOOD INTO THE REST OF
GOGEBIC AND ONTONAGON COUNTIES THROUGH THE DAY TODAY...EVENTUALLY
REACHING IRON/HOUGHTON COUNTIES THIS EVENING AS THE LIMITED MIXING
DECREASES AND THE STRATUS CAN REALLY EXPAND. THESE LOW CLOUDS
(ALONG WITH MID CLOUDS FROM THE WEAK UPPER TROUGH AXIS SHIFTING EAST
INTO MINNESOTA) WILL CONTINUE TO SPREAD ACROSS UPPER MICHIGAN FROM
SOUTHWEST TO NORTHEAST TONIGHT AS SOUTHWESTERLY FLOW GRADUALLY
DEVELOPS.

AS FOR TEMPERATURES...EVEN WITH THE COLD START THIS MORNING IN
SOME LOCATIONS...EXPECT ANOTHER DAY OF HIGHS A LITTLE BIT
ABOVE NORMAL (UPPER 20S TO LOWER 30S). THE LOWS TONIGHT WILL BE
TRICKY...AS THEY DEPEND ON THE LOCATIONS OF THE CLOUD COVER. WHERE
SKIES ARE CLEAR OVER THE CENTRAL AND EAST...WOULD EXPECT ANOTHER
QUICK DROP TO TEMPS IN THE EVENING AND NEARING 0 UNDER LIGHT WINDS.
BUT WHERE THERE ARE CLOUDS...TEMPS WILL STRUGGLE TO FALL INTO THE
MID TEENS. WILL KEEP LOWS UP THE HIGHEST OVER THE FAR WEST...WHERE
THE CLOUDS WILL MOST LIKELY BE LOCATED.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 254 PM EST FRI DEC 19 2014

NAM SHOWS A 500 MB TROUGH OVER THE UPPER GREAT LAKES 00Z SUN WITH A
CLOSED LOW OVER WESTERN ONTARIO WITH A SHORTWAVE OVER THE CANADIAN
PRAIRIES. THIS SHORTWAVE DIGS SOUTHEAST AND FORMS A CLOSED 500 MB
LOW OVER THE UPPER MISSISSIPPI RIVER VALLEY 00Z TUE.

KEPT SAT NIGHT THROUGH SUN MORNING DRY WITH PCPN OFF TO THE WEST AND
NORTHWEST OF THE AREA AND THEN START TO BRING IN SOME SLIGHT CHANCES
FOR SNOW SUN AFTERNOON AND THEN START TO BRING IN SOME CHANCE POPS
FOR SUN NIGHT INTO MONDAY. DID NOT MAKE TOO MANY CHANGES TO THE
GOING FORECAST FOR TEMPERATURES. DID KEEP IN SOME RAIN/SNOW MIX FOR
MONDAY AFTERNOON.

IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB CLOSED LOW NEARING THE
UPPER GREAT LAKES 12Z TUE EMBEDDED IN A TROUGH OVER THE PLAINS
STATES. THE TROUGH AND UPPER LOW MOVE SLOWLY EAST 12Z WED AND ARE
EAST OF THE AREA INTO THE LOWER GREAT LAKES 12Z THU FOLLOWED BY
SHORTWAVE RIDGING OVER THE PLAINS. THIS RIDGING MOVES INTO THE UPPER
GREAT LAKES 12Z FRI. THIS SYSTEM FOR MONDAY NIGHT INTO THURSDAY IS
STILL NOT WELL HANDLED BY THE MODELS. THE ECMWF CONTINUES WITH A
FURTHER SOUTH TRACKING OF THE SFC LOW WHICH WOULD GIVE US COLDER AIR
AND MORE SNOW WHILE THE GFS TRACK IS FURTHER NORTH. THERE IS ALSO A
QUESTION OF IF THIS SYSTEM WILL GO FURTHER SOUTH AND EAST AND TURN
INTO AN EAST COAST STORM RATHER THAN A GREAT LAKES STORM. LOOKING AT
THE NEW ECMWF...IT CONTINUES TO GO WITH A GREAT LAKES SYSTEM...BUT
THE 500 MB TROUGH BECOMES VERY NEGATIVELY TILTED. HAVE A FEELING THE
FURTHER SOUTH AND EAST SOLUTION MAY VERIFY WITH THE EAST COAST STORM
THOUGH AND HOPEFULLY LATER MODEL RUNS WILL BE ABLE TO FIGURE THIS
OUT. WILL CONTINUE TO HIGHLIGHT THIS IN THE HWO FOR NOW AS THE PCPN
TYPE AND SNOW AMOUNTS ARE HIGHLY DEPENDENT ON THE TRACK TO THE SFC
LOW AND THERE WILL BE SOME LAKE ENHANCEMENT TO THE SNOW AS WELL.
TEMPERATURES WILL BE ABOVE NORMAL FOR THIS FORECAST PERIOD. BUMPED
UP WINDS IN THE EXTENDED FROM 06Z THU ONWARD AS PRESSURE GRADIENT
TIGHTENS.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1246 PM EST FRI DEC 19 2014

EXPECT LITTLE CHANGE THROUGH THE TAF PERIOD AS WARM AIR AND MOISTURE
ADVECTION CONTINUES BETWEEN A HIGH PRESSURE SYSTEM TO THE EAST AND A
TROUGH OVER THE NORTHERN PLAINS. MODELS ARE HAVING TROUBLE
REPRESENTING LOW LEVEL CLOUDS OVER KCMX AND KSAW. MODELS SHOW CLOUDS
MOVING NORTHEAST AND DIMINISHING...BUT CLOUDS HAVE BEEN STEADILY
EXPANDING THIS MORNING. FOR THIS REASON...THERE IS A GOOD AMOUNT OF
UNCERTAINTY WITH CIGS THROUGH THE TAF PERIOD. DO THINK THAT KSAW WILL
SCATTER OUT FOR A TIME THIS EVENING...WHICH MAY ALLOW FOG TO FORM AT
THE SITE. KCMX MAY CLEAR OUT THIS AFTERNOON/EVENING...BUT WAS LESS
CONFIDENT SO DID NOT INCLUDE THAT IN THE TAF.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 345 AM EST FRI DEC 19 2014

EXPECT LIGHT WINDS UNDER 20 KTS ASSOCIATED WITH HI PRES PASSING THRU
THE UPPER LAKES TODAY TO SHIFT TO THE S BUT REMAIN UNDER 20 KTS
UNTIL AT LEAST SUN. THE S WINDS MAY INCREASE UP TO 25 KTS OVER
MAINLY THE E HALF OF THE LAKE LATER SUN INTO MON IN ADVANCE OF AN
APPROACHING LO PRES. AS ANOTHER LO PRES DEVELOPS TO THE S...THE FLOW
WILL TEND TO BACK AND WEAKEN ON TUE. DEPENDING ON HOW QUICKLY THIS
SECOND LO DEVELOPS AND WHERE IT TRACKS...THERE COULD BE A NW GALE
EVENT ON WED OR XMAS DAY.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...SRF
LONG TERM...07
AVIATION...TITUS
MARINE...KC







AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 1249 PM EST FRI DEC 19 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM EST FRI DEC 19 2014

A FAIRLY QUIET PATTERN IN THE CENTRAL PART OF THE CONUS...AS THE
SOUTHERN STREAM JET IS SITUATED OVER THE SOUTHERN TIER OF STATES
AND THE SYSTEM THAT BROUGHT SNOW TO THE AREA THIS PAST
TUESDAY/WEDNESDAY IS NOW SPINNING OVER PRINCE EDWARD ISLAND. CLOSER
TO THIS AREA...AN UPPER RIDGE STRETCHES FROM WISCONSIN TO JAMES
BAY...WHILE A UPPER TROUGH IS LOCATED OVER SASKATCHEWAN AND THE
NORTHERN PLAINS. BENEATH THE UPPER RIDGE...1028MB HIGH PRESSURE IS
CENTERED OVER NORTHERN LAKE SUPERIOR WITH A RIDGE STRETCHING SOUTH
THROUGH THE MID MISSISSIPPI VALLEY. THERE IS PLENTY OF DRY AIR ALOFT
ON THE RAP ANALYSIS ASSOCIATED WITH THIS UPPER RIDGE...BUT THE
SUBSIDENCE HAS STRENGTHENED THE INVERSION OVER THE GREAT LAKES AND
UPPER MISSISSIPPI VALLEY REGIONS AND AIDED IN AREAS OF LOW CLOUDS.
THE LARGEST AREA OF LOW CLOUDS COVERS MUCH OF MINNESOTA AND WESTERN
WISCONSIN...WITH THE EASTERN EDGE STRETCHING FROM GRAND MARAIS
MINNESOTA THROUGH IRONWOOD MICHIGAN AND TOWARDS MADISON WISCONSIN.
BUT THERE IS A POCKET OF CLOUDS THAT DEVELOPED OVER SOUTH CENTRAL
LAKE SUPERIOR LATE THIS EVENING (AIDED BY MARGINAL DELTA-T VALUES
FOR LAKE CLOUDS) AND WITH THE LIGHT NORTHERLY FLOW...SHIFTED INTO
THE KEWEENAW AND NORTH CENTRAL U.P.  DEFINITELY HAVE TO GIVE SOME
CREDIT TO THE REGIONAL GEM...WHICH SUPERBLY PICKED UP ON THESE
CLOUDS WITH THE 00Z RUN YESTERDAY. THESE CLOUDS ALLOWED TEMPERATURES
TO QUICKLY RISE AROUND 10 DEGREES AND LOCATIONS UNDER THEM ARE IN
THE MID-UPPER TEENS. ELSEWHERE IN THE U.P. SKIES ARE CLEAR AND WITH
THE LIGHT WINDS...TEMPERATURES HAVE FALLEN INTO THE LOWER SINGLE
DIGITS ABOVE AND BELOW ZERO.

THE UPPER RIDGE AND SURFACE HIGH CURRENTLY OVER THE AREA WILL
SLOWLY SHIFT EAST-SOUTHEAST TODAY AND TONIGHT...ALLOWING THE AREA
TO COME UNDER GREATER INFLUENCE OF THE WEAK UPPER TROUGH. THE LOW
CLOUDS WILL BE THE PRIMARY CONCERN FOR THE FORECAST FOR TODAY. WITH
GENERALLY LIGHT WINDS AND A RELATIVELY LOW SUN ANGLE...GETTING A
HANDLE ON THE LOW CLOUDS OVER THE NORTH CENTRAL AND KEWEENAW IS
DIFFICULT. FOLLOWING 925MB WINDS IN THE MODELS...WOULD EXPECT THEM
TO TRY TO NOSE A LITTLE FARTHER INLAND OVER THE CENTRAL (AND EVEN
THE EASTERN) PART OF THE U.P. TODAY...WHILE THE DEVELOPING LIGHT
SOUTHERLY FLOW WOULD LIKELY PULL DRIER AIR BACK INTO THE KEWEENAW
AND PUSH THOSE CLOUDS NORTH. BUT THAT INCREASING SOUTHERLY FLOW
WILL ALSO PULL THE CLOUDS RIGHT NEAR IRONWOOD INTO THE REST OF
GOGEBIC AND ONTONAGON COUNTIES THROUGH THE DAY TODAY...EVENTUALLY
REACHING IRON/HOUGHTON COUNTIES THIS EVENING AS THE LIMITED MIXING
DECREASES AND THE STRATUS CAN REALLY EXPAND. THESE LOW CLOUDS
(ALONG WITH MID CLOUDS FROM THE WEAK UPPER TROUGH AXIS SHIFTING EAST
INTO MINNESOTA) WILL CONTINUE TO SPREAD ACROSS UPPER MICHIGAN FROM
SOUTHWEST TO NORTHEAST TONIGHT AS SOUTHWESTERLY FLOW GRADUALLY
DEVELOPS.

AS FOR TEMPERATURES...EVEN WITH THE COLD START THIS MORNING IN
SOME LOCATIONS...EXPECT ANOTHER DAY OF HIGHS A LITTLE BIT
ABOVE NORMAL (UPPER 20S TO LOWER 30S). THE LOWS TONIGHT WILL BE
TRICKY...AS THEY DEPEND ON THE LOCATIONS OF THE CLOUD COVER. WHERE
SKIES ARE CLEAR OVER THE CENTRAL AND EAST...WOULD EXPECT ANOTHER
QUICK DROP TO TEMPS IN THE EVENING AND NEARING 0 UNDER LIGHT WINDS.
BUT WHERE THERE ARE CLOUDS...TEMPS WILL STRUGGLE TO FALL INTO THE
MID TEENS. WILL KEEP LOWS UP THE HIGHEST OVER THE FAR WEST...WHERE
THE CLOUDS WILL MOST LIKELY BE LOCATED.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM EST FRI DEC 19 2014

MAIN FCST CONCERNS IN THE MEDIUM/EXTENDED RANGE INCLUDE POPS ON SUN
NGT INTO MON AS A WAA REGIME DEVELOPS IN THE UPR LKS BTWN HI PRES
MOVING INTO NEW ENGLAND AND LO PRES TAKING SHAPE IN THE NRN PLAINS
ASSOCIATED WITH A STRONGER SHRTWV RIDING OVER A RDG ALONG THE W
COAST. THE POTENTIAL FOR A HEAVIER SYNOPTIC THEN LK ENHANCED SN IS
STILL THERE FOR TUE THRU XMAS AS THE DIGGING SHRTWV DEEPENS AN UPR
TROF OVER THE CENTRAL CONUS AND A LO PRES SOMEWHERE IN THE GREAT
LKS. BUT THERE REMAINS SOME INCONSISTENCIES AMONG THE MEDIUM/LONG
RANGE GUIDANCE ON THIS LO AND HOW QUICKLY A SECOND LO WL TAKE
SHAPE...SO CONFIDENCE IS LO ON THE FCST FOR MON THRU XMAS.

SAT/SAT NGT...A SFC HI PRES RDG STRETCHING FM WRN QUEBEC INTO THE
MID MS RIVER VALLEY ON SAT MRNG WILL MOVE SLOWLY TO THE E AND TO
NEAR NEW ENGLAND TO THE OH RIVER VALLEY BY 12Z SUN UNDER LGT W FLOW
ALOFT. A WEAK SHRTWV EMBEDDED IN THIS W FLOW WL BE DRIFTING THRU THE
UPR LKS DURING THIS PERIOD. ALTHOUGH THERE WL BE SOME WAA IN THE SW
FLOW ON THE BACK SIDE OF THE DEPARTING HI AND PVA IN ADVANCE OF THE
SHRTWV...MODELS SHOW ONLY WEAK ISENTROPIC ASCENT/DEEP LYR QVECTOR
CNVGC/UVV IN THE ABSENCE OF SGNFT MSTR INFLOW. SINCE FCST SDNGS
INDICATE LIMITED DEEP SATURATION...WL MAINTAIN GOING DRY FCST AND
MOCLDY SKIES. TEMPS SHOULD RUN ABOVE NORMAL FOR THE SEASON WITH H85
TEMPS NOT FAR FM -5C TO -7C.

SUN/SUN NGT...MOST OF THE MEDIUM RANGE OPERATIONAL MODELS SHOW
ANOTHER MORE COMPACT SHRTWV CROSSING THE UPR LKS ON LATE SUN INTO
EARLY MON ACCOMPANIED BY SOME SHARPER DPVA. IN TANDEM WITH SOME MORE
IMPRESSIVE ISENTROPIC ASCENT IN THE SSW FLOW BTWN THE DEPARTING HI
PRES RDG TO THE E AND FALLING MSLP IN THE NRN PLAINS ASSOCIATED WITH
A STRONGER SHRTWV RIDING THRU THE NRN ROCKIES AND OVER THE UPR RDG
OFF THE W COAST...MODELS DO GENERATE SOME WIDESPREAD ALBEIT LGT PCPN
AT TIMES DURING THIS PERIOD. THE GFS SHOWS A WEAKER SHRTWV/DYNAMIC
FORCING...BUT ENUF ISENTROPIC ASCENT TO GENERATE SOME LGT PCPN AS
WELL. FCST WL SHOW A PERIOD OF UP TO HI CHC POPS TO REFLECT MODEL
DISCREPANCIES ON THE TIMING OF THE STRONGER UVV. SSW FLOW UP THE
LENGTH OF LK MI MAY SUPPORT SOME HIER POPS OVER THE E...BUT MARGINAL
CHILL OF THE AIRMASS FOR LK ENHANCEMENT AND SOME SHEAR SHOULD LIMIT
THE POTENTIAL FOR A SGNFT IMPACT. TEMPS WL REMAIN ABOVE NORMAL...
ESPECIALLY ON SUN NGT WITH CLD COVER AND A STEADY S WIND GREATLY
LIMITING THE DIURNAL TEMP FALL.

MON THRU XMAS DAY...ALTHOUGH THE MEDIUM/LONG RANGE GUIDANCE ARE IN
AGREEMENT AN UPR TROF WL DEEPEN WITH AN H5 LO CLOSING OFF SOMEWHERE
OVER THE CENTRAL CONUS DOWNSTREAM OF THE RDG OVER THE FAR W AND THAT
THE CLOSED LO/UPR TROF WL TAKE ON A NEGATIVE TILT BY LATE TUE/XMAS
EVE...THERE ARE CONSIDERABLE DIFFERENCES ON THE FCST MSLP AND
THERMAL FIELDS. THE 12Z AND 00Z GFS ENSEMBLE SPREAD ON THE FCST LO
POSITION ON TUE/WED WAS QUITE WIDE...REFLECTING THE RATHER POOR
PREDICTABILITY OF THIS PATTERN WITH THE MAIN PLAYERS STILL OUT OVER
THE DATA POOR PACIFIC OCEAN. IN GENERAL...THE GFS IS FARTHER N WITH
THE RESULTING SFC LO AND THUS SHOWS WARMER LLVL TEMPS THAT WOULD BE
SUFFICIENT FOR A GOOD DEAL OF THE PCPN TO FALL AS RA OVER A GOOD
PORTION OF THE CWA. THE 00Z ECWMF ON THE OTHER HAND SHOWS A FARTHER
S TRACK FOR THE SFC LO AND QUICKER REDEVELOPMENT OF A DEEPER SECOND
LO ASSOCIATED WITH THE SHARPLY DIGGING SHRTWV INTO THE TROF THAT ALL
THE MODELS EVENTUALLY LATCH ON TO AS THE MAIN FEATURE. THE 00Z UKMET
IS CLOSER TO THE ECMWF...WHILE THE CNDN IS MORE OF A COMPROMISE.
SINCE BOTH THE GFS/ECWMF HAVE SHOWN CONTINUITY FM PREVIOUS RUNS AND
THERE IS CONSIDERABLE DIFFERENCES...FOLLOWED A MODEL CONSENSUS APRCH
FOR FCST PREPARATION. DID INCREASE POPS ABOVE THE CONSENSUS ON WED/
THU NEAR LK SUP WITH CYC NE UPSLOPE FLOW SHIFTING TO THE NW BY XMAS
TO THE NW OF DEEPENING LO AND DRAWING COLDER AIR INTO THE UPR LKS
THAT WOULD BE SUFFICIENT FOR SOME LK ENHANCEMENT /H85 TEMPS NEAR
-10C ON XMAS/.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1246 PM EST FRI DEC 19 2014

EXPECT LITTLE CHANGE THROUGH THE TAF PERIOD AS WARM AIR AND MOISTURE
ADVECTION CONTINUES BETWEEN A HIGH PRESSURE SYSTEM TO THE EAST AND A
TROUGH OVER THE NORTHERN PLAINS. MODELS ARE HAVING TROUBLE
REPRESENTING LOW LEVEL CLOUDS OVER KCMX AND KSAW. MODELS SHOW CLOUDS
MOVING NORTHEAST AND DIMINISHING...BUT CLOUDS HAVE BEEN STEADILY
EXPANDING THIS MORNING. FOR THIS REASON...THERE IS A GOOD AMOUNT OF
UNCERTAINTY WITH CIGS THROUGH THE TAF PERIOD. DO THINK THAT KSAW WILL
SCATTER OUT FOR A TIME THIS EVENING...WHICH MAY ALLOW FOG TO FORM AT
THE SITE. KCMX MAY CLEAR OUT THIS AFTERNOON/EVENING...BUT WAS LESS
CONFIDENT SO DID NOT INCLUDE THAT IN THE TAF.

&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 345 AM EST FRI DEC 19 2014

EXPECT LIGHT WINDS UNDER 20 KTS ASSOCIATED WITH HI PRES PASSING THRU
THE UPPER LAKES TODAY TO SHIFT TO THE S BUT REMAIN UNDER 20 KTS
UNTIL AT LEAST SUN. THE S WINDS MAY INCREASE UP TO 25 KTS OVER
MAINLY THE E HALF OF THE LAKE LATER SUN INTO MON IN ADVANCE OF AN
APPROACHING LO PRES. AS ANOTHER LO PRES DEVELOPS TO THE S...THE FLOW
WILL TEND TO BACK AND WEAKEN ON TUE. DEPENDING ON HOW QUICKLY THIS
SECOND LO DEVELOPS AND WHERE IT TRACKS...THERE COULD BE A NW GALE
EVENT ON WED OR XMAS DAY.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...SRF
LONG TERM...KC
AVIATION...TITUS
MARINE...KC






AREA FORECAST DISCUSSION

NWS JACKSON MS

 1037 AM CST FRI DEC 19 2014

.UPDATE...

THE FORECAST IS GENERALLY ON TRACK FOR TODAY WITH WIDESPREAD LIGHT TO
MODERATE RAINFALL SPREADING EAST-NORTHEAST ACROSS MOST OF THE
ARKLAMISS. THE GREATEST MOISTURE FLUX/ASCENT HAS BEEN FOCUSING A BAND
OF HEAVIER RAIN OVER CENTRAL LA THAT SHOULD AFFECT THE I-20 CORRIDOR
THROUGH MID AFTERNOON. THEREAFTER...CONVECTIVE RAINFALL CURRENTLY
OVER SE TX/SW LA IS FORECAST BY THE HRRR TO ACCELERATE EASTWARD
ALONG THE COAST AND INTERCEPT BETTER MOISTURE FLUX. GUIDANCE
SUGGESTS THIS WILL HELP TO FOCUS BETTER LIFT AND HEAVIER RAINFALL
OVER SOUTHERN PORTIONS OF THE FORECAST AREA AS WE GO INTO THE
EVENING.

OVERALL...RAINFALL AMOUNTS OF 1-2 INCHES ALONG AND SOUTH OF I-20
STILL LOOK LIKE A REASONABLE FORECAST. OTHERWISE WILL BE MAKING SOME
MINOR ADJUSTMENTS TO TEMPERATURES TO ACCOUNT FOR LATEST TRENDS. /EC/

&&

.AVIATION...

DETERIORATING CONDITIONS WILL CONTINUE THROUGH THE AFTERNOON
AS A LOW PRESSURE SYSTEM MOVES ALONG THE GULF COAST AND SENDS
WIDESPREAD RAIN INLAND. MVFR CEILINGS SHOULD BE COMMON TODAY INTO
THIS EVENING WITH SOME MVFR VIS RESTRICTIONS. IN ADDITION THERE WILL
BE SOME OCCASIONAL IFR RESTRICTIONS... PARTICULARLY ALONG AND SOUTH
OF THE HKS/JAN TO MEI CORRIDOR WHERE THE HEAVIER RAINFALL IS
EXPECTED. /28/17/

&&

.PREV DISCUSSION... /ISSUED 345 AM CST FRI DEC 19 2014/

SHORT TERM...TODAY THROUGH SATURDAY NIGHT...AREA RADARS AND
SATELLITE ARE PICKING UP LIGHT TO MODERATE RAIN WITH SOME EMBEDDED
CONVECTION OVER SOUTHEAST TEXAS INTO SOUTHERN LOUISIANA PUSHING
TOWARD THE ARKLAMISS...ASSOCIATED WITH A STRONG SHORTWAVE TROUGH WAS
OBSERVED OVER THE SOUTHERN PLAINS. HIGH RES MODELS SHOW WIDESPREAD
MODERATE RAINS PUSHING INTO THE REGION FOR TODAY THROUGH TONIGHT.
MODEL CROSS SECTIONS AND SOUNDINGS CONTINUE TO SUPPORT SOME EMBEDDED
CONVECTION ACROSS THE SOUTH FOR TODAY. MODELS CONTINUE TO SUPPORT
STRONG ISENTROPIC ASCENT FOR POTENTIALLY HEAVY RAINFALL RATES...BUT
GUIDANCE HAS GENERALLY COME DOWN TO MAINLY ONE TO TWO INCHES SOUTH OF
INTERSTATE 20 WITH LIGHTER AMOUNTS FARTHER NORTH. SO WITH THIS IN
MIND WILL KEEP CURRENT WIDESPREAD POPS FOR TODAY AND LOWER POPS SOME
FOR TONIGHT. THE RAINS WILL MOVE OUT OF THE REGION ON SATURDAY
MORNING. ANOTHER SHORTWAVE WILL COME DOWN INTO THE SOUTHERN PLAINS ON
SUNDAY. IT WILL PUSH MOISTURE TOWARD THE REGION FROM THE SOUTH ON
LATE SUNDAY NIGHT AS CLOUDS INCREASE ACROSS THE REGION./17/

LONG TERM...SUNDAY THROUGH FRIDAY...SUNDAY MORNING A SURFACE RIDGE
AXIS FROM THE NORTHEAST WILL BE ACROSS THE NORTHERN PORTIONS OF OUR
CWA AND LIMIT ANY LOW LEVEL MOISTURE RETURN AHEAD OF THE NEXT UPPER
LEVEL TROUGH THAT WILL BE OVER THE CENTRAL CONUS. A WEAK SURFACE LOW
WILL DEVELOP OVER THE WESTERN GULF IN RESPONSE TO THE APPROACHING
TROUGH AND RESULT IN RAIN CHANCES OVER OUR SOUTHEAST ZONES SUNDAY
AFTERNOON. THIS SURFACE LOW WILL TRACK FARTHER SOUTH THAN THE ONE ON
FRIDAY. MODELS SHOW BY SUNDAY AFTERNOON THE RIGHT REAR QUAD OF A
>120KT JET STREAK OVER OUR SOUTHEAST COUNTIES BUT PWS WILL ONLY BE
ONE INCH OR LESS AND INSTABILITY WILL BE LIMITED SO ONLY LOW POPS OF
LIGHT QPF IS EXPECTED. THIS SYSTEM WILL SHIFT EAST OF OUR CWA BY
MONDAY MORNING BUT A CLOSED LOW WILL DROP OVER THE NORTHERN PLAINS
MONDAY RESULTING IN A DEEPENING OF THE UPPER LEVEL TROUGH OVER THE
CENTRAL CONUS. THIS WILL INDUCE WEAK WAA ADVECTION OVER OUR REGION
DURING THE DAY MONDAY AND RESULT IN A FEW LIGHT SHOWERS. THE
DEEPENING TROUGH WILL SUPPORT A STRONG COLD FRONT THAT IS EXPECTED
TO MOVE ACROSS OUR CWA TUESDAY. THE CHANCE FOR RAIN WILL INCREASE
AFTER MIDNIGHT MONDAY NIGHT AND THE HIGHEST POPS OF THE LONG TERM
WILL BE CARRIED ACROSS THE AREA ALONG AND AHEAD OF THE FRONT
TUESDAY. COOLER AND DRIER AIR WILL FILTER INTO THE REGION TUESDAY
NIGHT SENDING TEMPERATURES BELOW NORMAL BY WEDNESDAY MORNING. THE
GFS IS MUCH FARTHER NORTH THAN THE ECMWF WITH THE CLOSED LOW
WEDNESDAY MORNING AND ENDS THE RAIN FASTER. RAIN WILL LIKELY LINGER
LONGER INTO TUESDAY NIGHT THAN WAS THOUGH LAST NIGHT BUT DRY WEATHER
IS EXPECTED TO RETURN WEDNESDAY. THE CLOSED LOW WILL LIFT UP INTO
CANADA WEDNESDAY NIGHT AND THE UPPER TROUGH WILL SHIFT EAST OF OUR
CWA. THIS WILL LEAVE NEAR ZONAL FLOW ACROSS OUR CWA AND A WEAK
SURFACE LOW OVER THE NORTHERN GULF FOR CHRISTMAS DAY. CHRISTMAS DAY
WILL BE DRY BUT THE GFS AND ECMWF DIFFER SIGNIFICANTLY WITH THE NEXT
UPPER LEVEL TROUGH MOVING OVER THE ROCKIES. THE ECMWF IS MUCH
STRONGER WITH A CLOSED LOW AND ASSOCIATED SURFACE LOW OVER THE
CENTRAL CONUS BY FRIDAY MORNING. EITHER SOLUTION WILL BRING AN
INCREASE IN RAIN CHANCES DURING THE DAY FRIDAY. /22/

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.

&&

$$







AREA FORECAST DISCUSSION...UPDATED

NWS ST LOUIS MO

 1203 PM CST Fri Dec 19 2014

.UPDATE:
Issued at 1155 AM CST Fri Dec 19 2014

A few tweaks to going forecast...primarily to adjust chaotic cloud
cover over our IL counties and to raise temps there a degree or
two due to a bit more sun. Other change has been to pull mention
of drizzle over mid MO for this afternoon as stratus has
temporarily lifted here. However, did continue mention of flurries
over our se MO counties as very light echoes on n fringes of s
system showing up over nw AR, and heading to the NE.

Truett

&&

.SHORT TERM:  (Through Late This Afternoon)
Issued at 300 AM CST Fri Dec 19 2014

A weak ridge of high pressure which extends from the Great Lakes
region south through the Mid-Mississippi Valley is in control of our
weather today.  Soundings are showing plenty of low level moisture
trapped under an inversion at around 850mb.  The vertical structure
of the atmosphere is much like what we had last weekend with the
moisture stratified in the low levels, so I don`t expect much
sunshine for the majority of the area...with the possible exception
of south central and extreme southwest Illinois.  Some drier air is
trying to drift in on weak easterly low level flow.  Vertical cross
sections show intermittent weak upward motion through the day,
primarily over central Missouri, and short term guidance spits out a
hundredth of QPF here and there.  Additionally, the HRRR shows some
weak simulated radar echos over parts of central and southeast
Missouri today, so have added in a little patchy drizzle to the
forecast.

Carney

.LONG TERM:  (Tonight through Thursday)
Issued at 300 AM CST Fri Dec 19 2014

(Tonight - Saturday)

The brunt of a storm system is expected to pass relatively unnoticed
to our south this evening, and if it weren`t for some interaction
with a more northerly component, would probably result in no
precipitation anywhere, but such as it is, some very light snow
looks to be possible early this evening for an area primarily south
of STL metro.  This arrangement should be short-lived, with much of
the mid and upper level moisture quickly being shunted off to the
east, leaving behind extensive low cloud cover.  At this point,
there is good model consensus on a weak WAA, convergence regime
setting up at the low levels that noses into central MO by midnight
tonight and then snaking its way northward towards the UIN area by
Saturday morning.  Have added in patchy drizzle as a result.  For
now, expecting influence of the surface RIDGE to trump this for STL
metro and areas S and E.  Temps will probably not go very far
tonight with clouds hanging tough, although where the surface RIDGE
is dominant, should see a steady but slow drop...but for areas to
the N and W of STL metro where a light S flow will persist, near
steady temps are expected.  Speaking of temps, especially to the N
and W of STL metro where drizzle is expected to develop, readings
will be within a degree or two of the freezing mark and so this will
probably manifest more as patchy FZDZ for areas in northeast MO and
west-central IL.  Prefer the lower MOS temps for Saturday maxes
given cloud cover expected, but they should still rebound into the
upper 30s and low 40s.

(Sunday - Wednesday)

A rather deep upper level TROF is expected to develop later on
Sunday over the central CONUS and then take a good part of the week
before finally shifting east.  Maintained the highest PoPs for
Monday thru Tuesday, where there is good model consensus on when the
TROF will be close enough, yet its axis still just upstream...and
then reduce to slight chances by Wednesday when the TROF axis by
this time will have shifted to the east.

While much of the precipitation will be just rain, especially on the
front-end, enough cold air starts working in on Tuesday, especially
aloft, that will allow the atmosphere to sustain a changeover to
snow.  The only limiting factor at this point will be surface and/or
boundary layer temps that will ultimately determine the rain vs.
snow question.  GFS and EC MOS surface temps suggest this will not
happen for most locales until late in the day on Tuesday with snow
then expected as the dominant p-type from that point on.  This will
also be when the upper TROF axis will be crossing thru, and so what
is left will probably not be much, but perhaps light snow accums
will be possible Tuesday night and early Wednesday.  This will be
our only realistic chance at a white Christmas, and something to
watch, as a deeper system that digs a bit more south would up the
potential.

(Christmas)

Models have been advertising for several days now a transitional
period this day which should give us a net result of quiet wx with
near seasonal temps.  Nothing has changed with the current model
runs so will let it stand.

TES

&&

.AVIATION:  (For the 18z TAFs through 18z Saturday Afternoon)
Issued at 1155 AM CST Fri Dec 19 2014

Pocket of low level dry air on the IL side of the Mississippi
River continue to make for tricky aviation forecasts. Will
primarily go with MVFR cigs from 1.5-3kft this afternoon, although
its possible that sites along the river (KUIN and STL metro TAFs)
may be on the fringes of this cloud deck. Wedge of dry air is
forecast to hold firm tonight, and while it appears likely that
IFR fog and stratus will once again form over COU in the deeper
low level moisture, trend is less clear cut for sites along the
river. It`s interesting that most guidance isn`t as bullish as
yesterday with IFR development at UIN and STL metro, in spite of
the fact that low level flow does become a bit more southerly
during the predawn hours (albeit weakly so). So, for these
locations have headed towards lower end MVFR cigs/vsbys during the
predawn hours, with the expectation that the primary IFR deck will
remain just west of the MSRVR.

Specifics for KSTL: As mentioned above, area will be on the
western fringes of a pocket of drier low level air over IL. Have
generally gone with bkn MVFR cloud deck through 06z to try to
reflect this, but a slight shift in the edge of this moisture
could mean more or less cloudiness in the MVFR range. Forecast
hints at some lower vsbys and cloudiness during the predawn hours,
but based on the preponderence of guidance have maintained
prevailing ceiling and vsbys in the MVFR range.

Truett

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX






AREA FORECAST DISCUSSION

NWS HASTINGS NE

 243 PM CST FRI DEC 19 2014

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 238 PM CST FRI DEC 19 2014

SATELLITE AND OBSERVATIONS SHOW THE EDGE OF THE LOW CLOUDS IN THE
FAR WESTERN PART OF THE FORECAST AREA. FOG HAS BEEN PERSISTENT NEAR
THE EDGE OF THE LOW CLOUDS. VISIBILITIES HAVE IMPROVED IN THE PAST
HOUR OR SO...BUT SOME LIGHT FOG PERSISTS.

WATCHING THE VERY SLOW PROGRESSION OF THE CLOUDS TO THE EAST HAVE
BEEN INCLINED TO KEEP THE CLOUDS LONGER THAN EARLIER THOUGHT. UNDER
THE CLOUDS THE WINDS ARE FROM THE SOUTH OR EVEN THE SOUTHEAST A BIT
AND THIS HAS MADE IT HARD FOR THE CLEARING LINE TO CONTINUE MOVING
TO THE EAST. ON THE OTHER HAND UNDER THE CLEAR SKIES THE WINDS ARE
FROM THE WEST AND SHOULD BE PUSHING DRIER AIR DOWN SLOPE WHICH
SHOULD HELP THE CLEARING. AT THIS TIME THE SOUTH WINDS SEEM TO BE
WINNING THAT BATTLE.

TWO MAIN QUESTIONS REMAIN FOR THE FORECAST. FIRST HOW FAR EAST WILL
THE CLOUDS MOVE AND SECOND WHETHER THERE WILL BE FOG NEAR THE EDGE
OF THE STRATUS. A BROAD SURFACE TROUGH JUST TO THE WEST OF THE
FORECAST AREA WILL MOVE TO THE EAST DURING THE NIGHT. THIS SHOULD
HELP WINDS TO TURN TO THE WEST EVEN THOUGH THEY SHOULD BE LIGHT.
EXPECT THAT THE WEST WINDS WILL HELP TO PUSH THE CLOUDS TO THE EAST
A LITTLE DURING THE NIGHT. CLOUDS SHOULD HOLD TOUGH IN THE
EAST...BUT THE WEST ESPECIALLY AND EVEN THE CENTRAL PART OF THE
FORECAST AREA COULD SEE SOME CLEARING DURING THE NIGHT. THAT BRINGS
WITH IT THE COOLING TEMPERATURES THAT HAVE BEEN EVIDENT IN THE WEST
DURING THE MORNING TODAY. COOLER TEMPERATURES AND LIGHT WINDS SHOULD
ALLOW FOR SOME FOG ACROSS THE AREA. HOW MUCH...WHERE AND HOW LOW
WILL BE VISIBILITY BE ARE ALL QUESTIONS THAT PROVIDE A CHALLENGE.
SINCE MANY LOCATIONS ACROSS THE FORECAST AREA HAVE YET VISIBILITY OF
MORE THAN 5 MILES...WILL MAKE THE ASSUMPTION THAT THE LIGHT FOG
SHOULD LIFT A LITTLE THIS AFTERNOON...BUT RETURN DURING THE NIGHT.
HAVE KEPT PATCHY FOG ACROSS THE FORECAST AREA LATE TONIGHT. THE
LOWEST VISIBILITIES WILL BE NEAR THE EDGE OF THE CLOUDS. CURRENTLY
THE NAM AND HRRR ARE THE ONLY MODELS THAT INDICATE THERE WOULD BE
SOME FOG AROUND THE AREA. THE NAM KEEPS IT FURTHER TO THE EAST AND
FAIRLY LIGHT WHILE THE HRRR GIVES SOME LOWER VISIBILITIES FURTHER
WEST. WITH THE CURRENT FORECAST FOR WHERE THE CLEARING LINE WILL BE
LATE TONIGHT EXPECT THE LOWEST VISIBILITIES TO BE IN THE CENTRAL
PART OF THE FORECAST AREA BUT NOT SURE HOW LOW THE VISIBILITY WILL
BE...ALTHOUGH WITH THE PAST FEW NIGHTS AS A MODEL EXPECT THERE COULD
BE SOME VISIBILITIES LESS THAN A MILE SOMEWHERE.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 238 PM CST FRI DEC 19 2014

A PROGRESSIVE WEST NORTHWESTERLY FLOW IS EXPECTED TO BE IN PLACE
ACROSS THE REGION TO START THE EXTENDED PERIODS...WITH AN UPPER
LEVEL SHORTWAVE ACROSS THE PACIFIC NORTHWEST FORECAST TO DIVE INTO
THE PLAINS SUNDAY NIGHT THROUGH MONDAY. AS THIS DISTURBANCE DEEPENS
ACROSS THE MISSISSIPPI RIVER VALLEY AND TRACKS INTO THE GREAT LAKES
REGION...NORTHWESTERLY FLOW WILL PERSIST ALOFT...AND COULD SEE
ANOTHER UPPER LEVEL WAVE DIVE ACROSS THE LOCAL AREA TUESDAY NIGHT OR
WEDNESDAY. WHILE MODELS DISAGREE ON THE TIMING OF THIS NEXT
WAVE...THEY DIVERGE EVEN MORE AS WE TRANSITION INTO CHRISTMAS DAY
AND BEYOND...WITH THE EC STILL MAINTAINING A MUCH BROADER TROUGH
ACROSS THE WESTERN STATES AND THE GFS KEEPS THIS NEXT DISTURBANCE
MUCH FURTHER NORTH. DUE TO THE DIVERGENCE OF THE GUIDANCE...BLENDED
FORECAST DROPPED POPS FOR CHRISTMAS NIGHT AND THE DAY AFTER...AND
GIVEN THE UNCERTAINTY...SAW NO REASON TO TINKER WITH THE CHANCE OF
SNOW FOR THE TIME BEING.

STARTING OFF SUNDAY...EXPECT THE LOW LEVEL STRATUS THAT HAS BEEN
PERSISTENT ACROSS THE LOCAL AREA FOR MUCH OF THE LAST 10 DAYS TO BE
EAST OF THE LOCAL AREA AND CLOSER TO THE MISSOURI RIVER IN RESPONSE
TO A SURFACE TROUGH SLOWLY PUSHING ACROSS THE CENTRAL PLAINS. WITH
THE FOCUS OF SOME FOG ON THE WESTERN EDGE OF THIS STRATUS THE PAST
FEW DAYS...THINK IT IS PROBABLE THAT WE MIGHT STILL SEE SOME FOG
FROM ROUGHLY HIGHWAY 281 EASTWARD TO START THE DAY SUNDAY...CLOSER
TO THE EDGE OF THE STRATUS. AS A RESULT OF THIS...OPTED TO INTRODUCE
PATCHY FOG TO THE FORECAST FOR THIS AREA SUNDAY MORNING.
THEREAFTER...THE SURFACE FLOW IS EXPECT TO SHIFT AND BECOME MORE
WESTERLY THROUGH THE DAY SUNDAY...AND THIS DOWNSLOPING COMPONENT OF
THE WIND COMBINED WITH AT LEAST PARTLY SUNNY SKIES...SHOULD MAKE FOR
A RELATIVELY NICE FINISH TO THE WEEKEND...WITH TEMPERATURES EXPECTED
TO CLIMB INTO THE 40S SUNDAY AFTERNOON.

BEHIND THE SURFACE TROUGH...EXPECT THE NEXT UPPER LEVEL DISTURBANCE
TO SLIDE ACROSS THE LOCAL AREA LATE SUNDAY NIGHT INTO
MONDAY...BRINGING MAINLY THE CHANCE FOR RAIN TO THE LOCAL AREA.
BRIEFLY CONTEMPLATED INTRODUCING A RAIN SNOW MIX FOR THE EARLY
MORNING HOURS MONDAY GIVEN SURFACE TEMPS NEAR FREEZING...BUT LOOKING
AT THE ATMOSPHERIC PROFILE AND WARM LAYER ALOFT...THIS THE IS LIKELY
TO BE MAINLY A LIGHT RAIN EVENT FOR THE MAJORITY OF THE AREA. AS THE
MAIN UPPER LEVEL LOW MOVES INTO THE MISSISSIPPI RIVER VALLEY MONDAY
AFTERNOON...EXPECT SOME WRAP AROUND MOISTURE TO POTENTIALLY CLIP THE
NORTHERN AND EASTERN PORTIONS OF THE FORECAST AREA MONDAY NIGHT INTO
TUESDAY...WITH A LIGHT DUSTING OF SNOW POSSIBLE OVER THIS PERIOD. AS
THE FLOW REMAINS NORTHWESTERLY ALOFT BEHIND THE DEPARTING SYSTEM...A
SECONDARY UPPER LEVEL WAVE IS PROGGED TO CROSS THE NORTHERN AND
CENTRAL PLAINS TUESDAY NIGHT OR WEDNESDAY. DUE TO DIFFERENCES IN
GUIDANCE...THE CONFIDENCE OF ANY PRECIP OVER THIS PERIOD IS LOW AND
KEPT TEMPERATURES SEASONAL AND FORECAST DRY TUESDAY NIGHT THROUGH
CHRISTMAS DAY AS A RESULT.

THEREAFTER...WHAT LOOKED LIKE A DECENT CHANCE FOR SNOW LATE IN THE
EXTENDED PERIODS APPEARS A BIT MORE IN QUESTION THIS AFTERNOON AS
SIGNIFICANT DIFFERENCES IN THE HANDLING OF THE NEXT SYSTEM ARE
APPARENT. AS A RESULT...AS PREVIOUSLY MENTIONED...SAW NO REASON TO
DIVERGE FROM BLENDED FORECAST AS CONFIDENCE IN ANY ONE PARTICULAR
SOLUTION IS LOW THIS FAR OUT.

&&

.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1120 AM CST FRI DEC 19 2014

FOG HAS BEEN PERSISTENT IN THE KEAR TERMINAL AREA...BUT THERE HAS
BEEN SOME LIGHT FOG IN THE KGRI TERMINAL AREA. EXPECT THERE WILL
BE AN IMPROVEMENT IN VISIBILITY THIS AFTERNOON. THE LOW CLOUDS
CONTINUE TO PROVE A CHALLENGE. THE WESTERN EDGE OF THE CLOUDS IS
TO THE WEST OF KEAR AND EXPECT THAT THERE COULD BE SOME BREAKS IN
THE LOW CLOUDS IN THE KEAR TERMINAL AREA...BUT DO NOT EXPECT IT TO
GET INTO KGRI. ONCE THE LOWER CLOUDS MOVE OUT THERE WILL LIKELY BE
SOME FOG REFORMING DURING THE OVERNIGHT HOURS.


&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

SHORT TERM...JCB
LONG TERM...ROSSI
AVIATION...JCB



AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

 1222 PM CST FRI DEC 19 2014

.SYNOPSIS...
ISSUED AT 328 AM CST FRI DEC 19 2014

A SURFACE RIDGE OF HIGH PRESSURE EXTENDS ACROSS THE GREAT LAKES REGION.
A SUBSTANTIAL AREA OF STRATUS EXTENDS ALONG THE WESTERN PERIPHERY OF
THE SURFACE HIGH ACROSS THE EASTERN DAKOTAS...THE EASTERN HALF OF
NEBRASKA AND MOST OF KANSAS. ON THE WESTERN EDGE OF THE
STRATUS...LOCALLY DENSE FOG TO A QUARTER MILE CONTINUES FROM NEAR
HAYES CENTER THROUGH NORTH PLATTE...BROKEN BOW AND BASSETT. FURTHER
EAST WITHIN THE STRATUS...PATCHY FOG WITH CURRENT VSBYS FROM 2-5SM.
TEMPERATURES IN WESTERN NEBRASKA RANGING FROM 29 AT ONL TO 12 AT
VTN.

&&

.UPDATE...
ISSUED AT 1222 PM CST FRI DEC 19 2014

PATCHY FOG CONTINUES TO HANG AROUND INTO THE MID AFTERNOON IN
HOLT...WHEELER AND GARFIELD COUNTIES...THE SLOWER EROSION IS
SIMILAR TO WHAT THE HRRR HAS BEEN SUGGESTING THOUGH THE HRRR ALSO
KEEP LOWER VSBYS ALL AFTERNOON. ACTUAL FCST HAS INCREASED VSBYS
LATER THIS AFTERNOON THERE...BUT CURRENT FCST HAS A REFORMATION
LATER THIS EVENING WHICH STILL LOOKS GOOD...THOUGH THE AREA MAY BE
REDEFINED A BIT. OTHERWISE THE MAXS TODAY WERE WARMED SLIGHTLY IN
THE CENTRAL SANDHILLS WHERE TEMPS SEEMS TO WARM MORE QUICKLY...BUT
THINK WARMEST MAXES WILL BE IN SNOW-FREE AREA OF HAYES AND
FRONTIER COUNTIES.

UPDATE ISSUED AT 953 AM CST FRI DEC 19 2014

HAVE DELAYED THE DISSIPATION OF THE FOG IN THE EASTERN PORTION OF
THE AREA FOR AN HOUR. LATEST SHORT RANGE MODELS INDICATE CLOUDS
MAY NOT FULLY CLEAR IN ERN HOLT AND ERN CUSTER COUNTIES...THOUGH
CURRENT SATELLITE TRENDS INDICATE MORE CLEARING THAN MODELS
SUGGEST. TEMPERATURES WILL BE HIGHLY DEPENDENT ON CLOUD COVER IN
THE EAST...AND EFFECT OF SNOW COVER WHERE SUN DOES SHINE.
OTHERWISE WITH LIGHT WINDS THE DAY SHOULD BE MORE QUIET THAN DAYS PAST.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 328 AM CST FRI DEC 19 2014

LOCALLY DENSE FOG ALONG THE WESTERN EDGE OF STRATUS WITH PATCHY FOG
FURTHER EAST TO PERSIST THROUGH MID MORNING ACROSS THE SOUTHEASTERN
ZONES. ONCE FOG BURNS OFF...STRATUS WILL SLOWLY CLEAR EAST OF A
BROKEN BOW THROUGH ONEILL LINE THIS AFTERNOON. TO THE WEST...MOSTLY
SUNNY SKIES. WITH SLIGHTLY WARMER H85 TEMPS TO NEAR 3C FROM VTN
SOUTHWEST THROUGH OGA AND IML SUPPORT HIGHS IN THE UPPER 30S TO NEAR
40. WITH LIGHT WINDS REMAINING SOUTH AND STRATUS LINGERING INTO THE
AFTERNOON AT ONL AND BARTLETT...HIGHS LIMITED TO THE LOWER 30S.
CURRENT FORECAST TO BE NEAR...BUT SLIGHTLY COOLER THAN MAV GUIDANCE
ALL AREAS DUE TO EXISTING SNOW COVER EFFECTS.

FOR TONIGHT...STRATUS SHOULD REMAIN JUST EAST OF THE FAR EASTERN
ZONES. EXPECTING AN INCREASING IN SOME MID AND HIGH CLOUDINESS AS AN
UPSTREAM DISTURBANCE TRACKS ACROSS MONTANA AND WYOMING. SUBSTANTIAL
ONSHORE MOISTURE WILL STREAM INTO THE PACIFIC NORTHWEST WITH
APPROACH OF A STRONGER DISTURBANCE. LOWS TO FALL  INTO THE MID
TEENS...WITH COLDER LOWS NEAR 10 ABOVE EASTERN PANHANDLE INTO THE
PLATTE RIVER VALLEY.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 328 AM CST FRI DEC 19 2014

12Z SATURDAY AND BEYOND. WEAK SURFACE TROUGH WILL RESIDE EAST OF
THE FORECAST AREA ON SATURDAY...PROVIDING FOR LIGHT WESTERLY
DOWNSLOPING FLOW OFF THE HIGH PLAINS. THIS WILL ALLOW FOR PARTIAL
CLEARING AND A WEAK PUSH OF WARM AIR ADVECTION OFF THE HIGHER
TERRAIN. H85 TEMPERATURES WARM SEVERAL DEGREES ABOVE 0C...WHICH
WILL PROVIDE FOR SFC HIGHS IN THE LOWER 40S...WITH SOME UPPER 30S
ACROSS THE FAR NORTHEAST WHERE FOG AND/OR STRATUS REMAINS IN THE
FORECAST SATURDAY MORNING. LATE SATURDAY AFTERNOON AND EVENING A
WEAK WAVE WILL DROP SOUTHEAST FROM THE NORTHERN ROCKIES ONTO THE
NORTHERN PLAINS. THIS WILL FORCE A WEAK BOUNDARY THROUGH WESTERN
NEBRASKA...EFFECTIVELY KEEPING THE BL SOMEWHAT MIXED. THE RESULT
WILL BE SLIGHTLY WARMER OVERNIGHT LOWS...WITH TEENS ANTICIPATED
WHERE THE ATMOSPHERE CAN FULLY DECOUPLE /RIVER VALLEYS/...BUT
LOWER 20S ELSEWHERE. SUNDAY...TEMPERATURES WARM ONCE AGAIN AS A
LEE TROUGH DEEPENS AND ALLOWS FOR A RETURN TO A SOUTHWESTERLY
TRAJECTORY OF THE LOWER TROPOSPHERIC FLOW. H85 TEMPS WARM TO NEAR
5C ACROSS MUCH OF THE SANDHILLS...THIS SHOULD TRANSLATE TO MID TO
UPPER 40S OVER MUCH OF THE REGION SUNDAY AFTERNOON. SUNDAY EVENING
THROUGH MONDAY...ALL AVAILABLE GUIDANCE INDICATES A SHORTWAVE
DIVING SOUTH ACROSS THE PLAINS. SUFFICIENT LIFT AND MOISTURE IS
SHOWN FOR PRECIPITATION WITHIN THE REGION...BUT SUBTLE DIFFERENCES
IN THE WAY THE LONGER RANGE MODELS HANDLE THE UPPER JET STRUCTURE
CREATES UNCERTAINTY IN THE FORECAST. THE GFS CONTINUES TO BE
SLIGHTLY EAST WITH THE STRONGER JET SUPPORT...WHILE THE ECMWF IS
SLIGHTLY WEST. THUS THERES A DISAGREEMENT ON WHERE THE STRONGEST
MID LEVEL FRONTOGENETIC FORCING WILL RESIDE...THE GFS FAVORS THE
EASTERN PANHANDLE SOUTHEAST THROUGH LINCOLN AND CUSTER
COUNTIES...THE EURO IS WEST OVER THE HIGHER TERRAIN OF
COLORADO/WYOMING. FOR THIS...DIDN/T GET TOO CARRIED AWAY ON POPS
JUST YET...MAINTAINING A SLIGHT CHANCE/LOW END CHANCE WORDING. IF
PRECIP OCCURS THERMO PROFILES INITIALLY FAVOR ALL RAIN ACROSS THE
FORECAST AREA SUNDAY EVENING...BUT ENOUGH UNCERTAINTY REMAINS
OVERNIGHT TO KEEP A MENTION OF RAIN OR SNOW GOING...ESPECIALLY
GOING INTO MONDAY AS THE GFS INDICATES A GOOD PUSH OF SUB 0C H85
AIR ACROSS THE FORECAST AREA...THE EC IS SLOWER TO ARRIVE WITH THE
COLD AIR. LIGHT QPF MAY CONTINUE INTO TUESDAY ACROSS OUR EAST AS
THE UPPER FLOW TURNS NORTHERLY AND ADDITIONAL UL ENERGY DIVE SOUTH
ACROSS THE PLAINS. TEMPERATURE PROFILES WOULD BE SUPPORTIVE OF ALL
SNOW AT THIS POINT.

THERE REMAINS A STRONG SIGNAL THAT A ROBUST UPPER LEVEL TROUGH WILL
DROP SOUTH INTO THE PACIFIC NORTHWEST MID-WEEK THEN PROCEED TOWARD
THE GREAT BASIN AND EVENTUALLY EMERGE ON THE PLAINS. THE MODELS ARE
ALSO SUGGESTING INCREASED FRONTOGENESIS ALONG/BEHIND A STRONG ARCTIC
FRONT POISED TO ARRIVE ATOP THE SANDHILLS ON CHRISTMAS.  THE MODELS
CONTINUE TO WAFFLE A BIT ON THE PROJECTED SYSTEM...BUT CONFIDENCE IS
SLOWLY INCREASING IN A POTENTIAL WINTER STORM FOR CHRISTMAS AND LATE
WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1132 AM CST FRI DEC 19 2014

MAINLY VFR FOR THE KVTN AND KLBF TAF PERIOD...HOWEVER THERE IS
STILL SOME POTENTIAL FOR FOG IN THE KLBF TAF PERIOD TWD EARLY
MORNING. WITH FULL SUNSHINE TODAY AND LIGHT WINDS THROUGH THE DAY
LITTLE VERTICAL MIXING OF THE MOIST BOUNDARY LAYER...A RESULT OF
MELTING SNOW...WILL OCCUR. THEREFORE AS TRANSIENT UPPER LEVEL HIGH
PRESSURE BUILDS IN THE PATTERN APPEARS POSSIBLE FOR FOG
DEVELOPMENT...ESPECIALLY IN RIVER VALLEY AREAS SUCH AS KLBF.
HOWEVER...SHORT RANGE HIGH RESOLUTION MODELS ARE NOT SUGGESTING
REDUCED VSBYS THIS FAR WEST OVERNIGHT AND THEREFORE CONFIDENCE IS
NOT HIGH ON THE 5SM BR FOR KLBF.

FOG REOCCURRANCE IS LIKELY ACROSS THE FAR EASTERN PORTION OF THE
FORECAST AREA OVERNIGHT...EAST OF A LINE FROM ATKINSON TO BROKEN BOW TO
STOCKVILLE.


&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...JWS
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...JACOBS
AVIATION...JWS






AREA FORECAST DISCUSSION

NWS BISMARCK ND

 1158 AM CST FRI DEC 19 2014

.UPDATE...
ISSUED AT 1149 AM CST FRI DEC 19 2014

FOG AND STRATUS CONTINUES ACROSS THE NORTH AND PORTIONS OF THE EAST
CENTRAL TODAY. WITH LITTLE TO MOVE THE STATUS AROUND WILL OPT FOR
PERSISTENCE AND KEEP CLOUDS AND FOG IN THROUGH THE AFTERNOON AND
INTO THE EVENING AS WELL.

UPDATE ISSUED AT 943 AM CST FRI DEC 19 2014

WILL EXTEND AREAS OF FOG FOR A FEW MORE HOURS NORTHWEST. OTHERWISE
AS FOG LIFTS PATCHY FREEZING DRIZZLE HAS DIMINISHED. TEMPERATURES
AND WINDS LOOK OK.

UPDATE ISSUED AT 640 AM CST FRI DEC 19 2014

VISIBILITIES IN FOG NORTH AND EAST CONTINUE TO VARY FROM TIME TO
TIME AND PLACE TO PLACE. THERE WAS GENERAL IMPROVEMENT IN
VISIBILITIES. THE DENSE FOG ADVISORY NORTHWEST WAS ALLOWED TO
EXPIRE. A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED FOR FOG...SOME
OF IT LOCALLY DENSE.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 405 AM CST FRI DEC 19 2014

FOG AND LOW CLOUDS ARE THE MAIN CONCERNS IN THE SHORT TERM.

CURRENT SURFACE ANALYSIS  INDICATES LOW PRESSURE IN THE LEE OF THE
ROCKIES WITH A TROUGH EXTENDING FROM NORTHERN ALBERTA TO THE WESTERN
DAKOTAS. AT UPPER LEVELS A BROAD TROUGH EXTENDED OVER THE CANADIAN
AND NORTHERN US PLAINS. A RATHER SHARP WESTERN EDGE TO LOW CLOUDS
EXTENDED FROM NEAR WILLISTON ACROSS LAKE SAKAKAWEA TO EAST OF
BISMARCK. MID LEVEL CLOUDS WERE ALONG AND SOUTH/WEST OF THE MISSOURI
RIVER AT 3 AM CST. EXPECT THE LOW CLOUDS TO CLEAR FROM WEST TO EAST
ACROSS SOUTH CENTRAL NORTH DAKOTA...BUT LATEST HRRR MODEL INDICATES
CLOUDS HANGING IN ACROSS THE NORTH. A SHORTWAVE ALOFT ON THE WESTERN
EDGE OF THE UPPER TROUGH WAS DIGGING SOUTHEAST ACROSS SOUTHWESTERN
NORTH DAKOTA INTO WESTERN SOUTH DAKOTA...AND MAY BE THE DRIVING
FORCE FOR THE MID CLOUDS MOVING IN AND THE LOWER CLOUDS DISSIPATING.

DENSE FOG STILL EVIDENT AT WILLISTON...ALTHOUGH VISIBILITIES HAVE
IMPROVED IN THE LAST HOUR AT OTHER PLACES WITHIN THE DENSE FOG
ADVISORY...SUCH AS TIOGA/STANLEY/CROSBY. BUT MINOT VISIBILITY IS ON
A DOWNWARD TREND. THUS WILL KEEP THE DENSE FOG ADVISORY GOING UNTIL
6 AM AND THEN RE-EVALUATE.

OTHERWISE WARM ADVECTION TODAY SHOULD ALLOW TEMPERATURES TO RISE
INTO THE MID/UPPER 20S NORTH AND EAST OF THE MISSOURI RIVER...AND
WELL INTO THE MID AND UPPER 30S SOUTH AND WEST OF THE RIVER. TONIGHT
A SHORTWAVE RIDGE ALOFT ENTERS WESTERN NORTH DAKOTA AHEAD OF AN
UPPER LEVEL SHORTWAVE MOVING EASTWARD OUT OF THE ROCKIES. LOWS
TONIGHT SHOULD REMAIN ABOVE AVERAGE IN THE TEENS AND LOWER 20S.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 405 AM CST FRI DEC 19 2014

THE SHORT TERM ISSUES...LOW CLOUDS AND LIGHT PRECIPITATION
INCLUDING FREEZING RAIN/FREEZING DRIZZLE AND PATCHY FOG...
CONTINUE INTO THE LONG TERM AS THE FORECAST AREA REMAINS UNDER A
MEAN TROUGH SURFACE AND ALOFT. WAVES COMING THROUGH SATURDAY AND
AGAIN SUNDAY ARE WEAK AND MOISTURE STARVED. HOWEVER...WITH WARMER
AIR ADVECTING IN ALOFT AHEAD OF EACH WAVE THERE IS A RISK OF
FREEZING RAIN SATURDAY MORNING / FREEZING DRIZZLE WITH LOW STRATUS
CLOUDS. WARM ADVECTION CONTINUES CHANGING ANY PRECIPITATION IN THE
SOUTHWEST TO RAIN WITH SURFACE TEMPERATURES INTO THE MID 30S
SATURDAY AFTERNOON. A SIMILAR SCENARIO SETS UP FOR SUNDAY.

THE MID LEVEL LOW...CUTTING OFF OVER WISCONSIN...WILL BLOCK THE
FLOW PATTERN UP ACROSS THE NORTHERN PLAINS. THIS WILL ALLOW COLDER
AIR TO SPILL IN FOR TUESDAY. LOOKING AHEAD TO CHRISTMAS DAY...THE
LOW TO THE EAST...AND HIGH PRESSURE MOVING ACROSS THE NORTHERN
ROCKIES...ALLOW A STEADY FLOW OF COLDER AIR INTO NORTH
DAKOTA...THAT WILL CONTINUE AT LEAST THROUGH THE HOLIDAY WEEKEND.
STILL THOUGH...TEMPERATURES ARE CLOSE TO WHAT IS NORMAL FOR THE
END OF DECEMBER...AROUND 20 DAYTIME AND SINGLE DIGITS ABOVE AND
BELOW AT NIGHT. PERIODS OF FLURRIES...MAYBE A FEW TENTHS INCH OF
SNOW AT MOST EVERY OTHER DAY OR SO...LOOKS TO OCCUR THROUGH THE
CHRISTMAS HOLIDAY WEEKEND.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1149 AM CST FRI DEC 19 2014

WILL LET PERSISTENCE DICTATE THE FORECAST WHERE LOW CLOUDS AND
AREAS OF FOG REMAIN AT NOON TODAY. KEPT LOW IFR FROM KMOT-KJMS
WHERE SHALLOW COOL AIR WILL REMAIN. KISN-KBIS WILL REMAIN ON THE
EDGE WITH SOME UNCERTAINTY AS TO THE EXTENT OF CLOUDS AND FOG
THAT RETURN AFTER DARK. WITH LITTLE IN THE WAY OF BROAD SCALE
WINDS SEE SHALLOW COOL BOUNDARY LAYER CONTRIBUTING TO STRATUS AND
FOG. KDIK PROBABLY THE ONLY ONE IN THE CLEAR WITH VFR EXPECTED.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...WAA
SHORT TERM...JV
LONG TERM...JPM
AVIATION...WAA






AREA FORECAST DISCUSSION

NWS MORRISTOWN TN

 316 PM EST FRI DEC 19 2014

.SHORT TERM...(TONIGHT AND SATURDAY)...
THERE REMAINS MUCH UNCERTAINTY IN THE SHORT TERM PERIOD DUE TO LARGE
DIFFERENCES BETWEEN THE NAM AND THE GFS. THE NAM IS THE WETTER AND
COLDER OF THE TWO MODELS. THE PREFERENCE IS MORE TOWARD THE GFS DUE
TO THE PRECIP/CONVECTION THAT IS EXPECTED TO DEVELOP ALONG THE GULF
COAST...PROVIDING A STABILIZING EFFECT UPSTREAM AND PREVENTING
NORTHWARD MOISTURE ADVECTION. THE RAP APPEARS TO AGREE WITH THIS
SCENARIO...AND THE LATEST SREF APPEARS TO BE TRENDING DOWNWARD IN
POPS/QPF.

AS A RESULT...WILL CONFINE LIKELY POPS TO EXTREME SOUTHERN PORTIONS
OF THE AREA TONIGHT...FADING TO LOW CHANCE POPS NORTH. QPF WILL BE
LIGHT...UP TO A TENTH OF AN INCH SOUTH AND IN THE MOUNTAINS. IN
HIGHER ELEVATIONS...MAINLY ABOVE 2500 FT...THE PRECIP SHOULD BE
MOSTLY SNOW...BUT WITH A SMALL WINDOW OF ADEQUATE MOISTURE DEPTH
INTO THE DENDRITE GROWTH ZONE AND WEAK LIFT...NO MORE THAN ONE INCH
IS EXPECTED TO ACCUMULATE. TRI-CITIES AND SW VA COULD SEE SOME SNOW
IF THE COLDER NAM IS CORRECT...BUT THE WARMER GFS LOOKS LIKE ALL
RAIN. WILL MENTION RAIN OR SNOW IN THAT AREA AS A COMPROMISE...WITH
WITH NO ACCUMULATIONS. THE FASTER EXIT OF PRECIP SHOWN BY THE GFS
WILL BE FOLLOWED...ENDING POPS IN THE EARLY AFTERNOON.

.LONG TERM (SATURDAY NIGHT THROUGH FRIDAY)...
A WEAK SYSTEM WILL BE EXITING TO THE NE SATURDAY NIGHT WITH SKY
CONDITIONS IMPROVING TO PARTLY CLOUDY. UPPER FLOW IS ZONAL WITH
DRIER AIR MASS AND WEAK HIGH PRESSURE SETTLING OVER THE REGION.
THE SURFACE HIGH WILL BE OVERHEAD SUNDAY WITH SKIES PARTLY TO
MOSTLY SUNNY AND HIGH TEMPERATURES SLIGHTLY ABOVE NORMAL IN THE
UPPER 40S TO MID 50S. ANOTHER SOUTHERN SYSTEM DEVELOPS ACROSS THE
GULF COAST SUNDAY AND BRINGS CLOUDS AND RAIN ACROSS THE FORECAST
AREA SUNDAY NIGHT AND MONDAY. AFTER A BRIEF BREAK IN THE STEADY
RAIN MONDAY NIGHT A MUCH STRONGER SYSTEM STILL LOOKS ON TRACK TO
MOVE INTO THE MS VALLEY MONDAY. A DEEP TROUGH OVER THE CENTRAL
STATES WILL MOVE INTO THE EASTERN STATES TUESDAY AND WEDNESDAY. A
STRONG COLD FRONT APPROACHES THE FORECAST AREA TUESDAY NIGHT INTO
WEDNESDAY. A SURFACE LOW DEEPENS OVER OH WEDNESDAY. THE SYSTEM
FINALLY SHIFTS EAST OF THE AREA ON CHRISTMAS DAY. THERE COULD BE
SOME THUNDERSTORMS IF ENOUGH INSTABILITY DEVELOPS TUESDAY AFTERNOON
AND EVENING AHEAD OF THE FRONT. MUCH COLDER TEMPERATURES WEDNESDAY
AND THURSDAY BEHIND THE FRONT. AS COLDER AIR MOVES IN LATE
WEDNESDAY AND WEDNESDAY NIGHT SOME MINOR SNOWFALL ACCUMULATIONS ARE
POSSIBLE IN THE HIGHER ELEVATIONS.

&&

.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN             36  51  36  54 /  70  20   0  10
KNOXVILLE MCGHEE TYSON AIRPORT, TN  34  45  33  52 /  40  30   0  10
OAK RIDGE, TN                       33  45  33  51 /  40  20   0  10
TRI CITIES AIRPORT, TN              31  43  30  49 /  40  40  10   0

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&

$$

DGS/TD



AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 1133 AM CST FRI DEC 19 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CST FRI DEC 19 2014

THE MAIN FORECAST CHALLENGE INTO TONIGHT IS WITH THE LOW LEVEL
MOISTURE AND WHETHER IT WILL BE ENOUGH TO PRODUCE SOME FREEZING
DRIZZLE OR FLURRIES.

CURRENTLY...A BAND OF 1-2KFT STRATUS THAT EXTENDS FROM NORTHWEST
WISCONSIN DOWN THROUGH SOUTHERN WISCONSIN HAS BEEN PRODUCING SOME
FLURRIES DUE TO SOME WEAK LIFT ASSOCIATED WITH A COLD FRONT THAT
EXTENDS FROM SOUTHERN MICHIGAN WEST-NORTHWEST INTO WESTERN
WISCONSIN. THIS FEATURE WILL PULL EASTWARD THIS MORNING/AFTERNOON
AND SHOULD TAKE THESE FLURRIES EAST AS WELL. TO THE SOUTHWEST
TOWARD DES MOINES...ANOTHER BAND OF LOW LEVEL MOISTURE ASSOCIATED
WITH SOME RETURN SOUTHERLY FLOW/WARM AIR ADVECTION HAS FORMED SOME
FREEZING DRIZZLE AND FLURRIES IN THAT REGION. THE QUESTION FOR
TODAY/TONIGHT IS WHETHER THAT FREEZING DRIZZLE/FLURRIES HOLDS
TOGETHER.

19.00Z NAM/GFS AND 19.06Z RAP SOUNDINGS CERTAINLY SHOW THE SURFACE
TO 800MB LAYER MOISTENING UP THROUGH TONIGHT...ITS JUST A MATTER
OF WHETHER THERE IS ANY LIFT THERE. GIVEN THAT THERE CURRENTLY IS
SOME PRECIPITATION OCCURRING UPSTREAM...THERE DOES APPEAR TO BE
ENOUGH LIFT AND HAVE GONE AHEAD AND ADDED A MENTION OF SOME
PATCHY FREEZING DRIZZLE IN FOR TODAY IN SE MN/NE IA WITH IT
SPREADING EASTWARD OVERNIGHT AS THE MOISTURE SHIFTS EAST. DMX HAS
REPORTED SOME FLURRIES OCCURRING AS WELL AT THE MOMENT MEANING
THAT THERE IS SOME ICE BEING INTRODUCED IN THE LOW LEVELS THOUGH
MOST OF THE FORECAST SOUNDINGS SHOW THAT SATURATED LAYER BEING TOO
WARM TONIGHT TO PRODUCE ANY FLURRIES LOCALLY. NOT SURE WHETHER
THIS FREEZING DRIZZLE IS GOING TO BE ADVISORY WORTHY GIVEN THAT
THERE IS NOT MUCH FOCUS FOR LOW LEVEL LIFT...BUT CONDITIONS WILL
HAVE TO BE MONITORED SINCE AIR/ROAD TEMPERATURES WILL BE BELOW
FREEZING.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 333 AM CST FRI DEC 19 2014

THE PATTERN BECOMES MORE ACTIVE GOING INTO THE LATER PORTION OF
THE WEEKEND ON INTO EARLY NEXT WEEK AS A SERIES OF MID LEVEL SHORT
WAVE TROUGHS PROPAGATE ON THROUGH. THE NEXT DECENT CHANCE FOR
PRECIPITATION APPEARS TO COME IN ON SUNDAY AS LOW LEVEL WARM AIR
ADVECTION WILL COMBING WITH SOME WEAK 700MB TROUGHING TO DEVELOP
SOME PRECIPITATION. PRECIPITATION TYPE IS TRICKY WITH THIS SYSTEM
AS THERE IS A WEAK WARM LAYER THAT REACHES +1 TO +2C AND WOULD
MELT SOME OF THE SNOW THAT FALLS THROUGH IT. THERE ALSO APPEARS
TO BE A DRY LAYER BETWEEN THE 700MB MOISTURE AND SURFACE/LOW LEVEL
MOISTURE WHICH BRINGS INTO QUESTION HOW DEEP THE LIFT REALLY WILL
BE. SURFACE TEMPERATURES WILL ALSO BE CLIMBING TOWARD AND ABOVE
FREEZING WHICH COMPLICATES HOW MUCH SNOW COULD ACCUMULATE. KEPT
SNOW ACCUMULATIONS ON THE LOW SIDE...HALF INCH OR LESS...GIVEN ALL
OF THE QUESTIONS WITH THIS ROUND OF PRECIP.

A DEEPER TROUGH DEVELOPS ACROSS THE DAKOTAS SUNDAY NIGHT INTO
TUESDAY AND WILL BRING A MORE WIDESPREAD SHOT OF
PRECIPITATION...MAINLY RAIN BEFORE CHANGING OVER TO SNOW ON THE
BACKSIDE TUESDAY. THE 19.00Z GFS/ECMWF ARE IN DECENT AGREEMENT
WITH THIS SYSTEM IN REGARD TO TIMING BUT ARE DIFFERENT WITH THEIR
PROGRESSION OF THE SURFACE LOW WITH THE GFS DIGGING DEEPER EARLIER
WITH THE ECMWF KEEPING PRECIPITATION AROUND A TAD LONGER. BOTH
MODELS HAVE THE SNOW OFF TO THE EAST BY CHRISTMAS DAY WITH JUST
SOME WEST TO NORTHWEST WINDS IN THE WAKE OF THE SYSTEM.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1133 AM CST FRI DEC 19 2014

IFR CEILINGS/MVFR VISIBILITY IN MIST IS STAYING JUST WEST OF
KRST/KLSE ACROSS MUCH OF CENTRAL MN/IA LATE THIS MORNING. LATEST
FORECAST GUIDANCE SUGGESTS THESE LOW CLOUDS WILL SLOWLY PUSH EAST
THROUGH THE PERIOD...BUT WITH A PREDOMINANT SOUTH WIND...DELAYED
ONSET OF LOWER CEILINGS AT KRST UNTIL 19.22Z AND AT KLSE UNTIL
20.03Z. PATCHY FREEZING DRIZZLE POSSIBLE OVERNIGHT...BUT COVERAGE
UNCERTAINTY PRECLUDES MENTION IN 19.18Z TAFS. WILL NEED TO WATCH
FOR A FURTHER LOWERING OF CEILINGS/VISIBILITY IN THE HOURS AROUND
DAYBREAK SATURDAY MORNING. OTHERWISE...CONDITIONS SHOULD REBOUND
SLIGHTLY NEAR THE END OF THE PERIOD. SOUTHERLY WINDS WILL
CONTINUE...GENERALLY 10 KTS OR LESS.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&

$$

SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...ROGERS