Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/04/14
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
801 PM MST FRI JAN 3 2014
.UPDATE...
&&
.SHORT TERM...WILL MAKE SOME CHANGES FOR THE TONIGHT FORECAST
INCLUDING STRONGER WINDS AND EARLIER FRONTAL PASSAGE OVER THE
NORTHEAST PLAINS. INITIAL COLD FRONTAL SURGE NOW ACROSS EAST
CENTRAL WYOMING AND JUST PASSED KTOR IN THE LAST HOUR AND SHOULD
BE INTO CYS BETWEEN 04-05Z. THIS SHOULD PUT THE FRONT INTO DENVER
BETWEEN 07-08Z. CURRENT OBSERVATIONS HAVE STRONG WINDS GUSTING IN
THE 25-40KT RANGE SO HAVE ALSO INCREASED WINDS CONSIDERABLY
OVERNIGHT WITH THE FRONT. GIVEN THE FASTER MOTION WILL ALSO START
THE SNOW EARLIER WITH LIKELY POPS BEFORE 12Z SATURDAY. THERE
APPEARS TO BE A LAG OF 1-2 HOURS BETWEEN THE FRONT AND LOWER
MOISTURE AND SNOW STARTING. THE SECONDARY SURGE IS OVER MONTANA AS
MSAS SURFACE 3HR CHANGE SHOWING A 9-10MB PRESSURE RISE OVER
EASTERN MONTANA. WOW...HAVEN`T SEEN THAT LARGE OF A RISE IN QUITE
SOME TIME. OVERALL MODELS SEEM TO HAVE WAY UNDERDONE THE STRENGTH
OF THIS SYSTEM AND FRONT.
NOT MUCH SNOW IN THE MOUNTAINS YET...BUT SHOULD BEGIN TO INCREASE
BETWEEN 10 PM AND MIDNIGHT. WON`T CHANGE THE SNOW HILITES BUT WILL
WORD THE STATEMENT FOR A BIT LATER ARRIVAL.
.AVIATION...EXPECT CONTINUED W-NW SURFACE WINDS AT LOCAL TERMINALS
BEFORE COLD FRONT MOVES IN BETWEEN 07-08Z. THE TIMING IS QUICKER
AND WINDS STRONGER THAN PREVIOUS FORECAST BASED ON CURRENT
OBSERVATIONS IN WYOMING. COULD SEE SOME GUSTS IN THE 30-35KT RANGE
ESPECIALLY AT DENVER. DUE TO THE EARLIER ARRIVAL EXPECT SNOW TO
BEGIN 1-2 HOURS AFTER FRONT PASSAGE SO THERE COULD BE SOME LIGHT
SNOW ACCUMULATION BEFORE 12Z.
&&
.PREV DISCUSSION... /ISSUED 353 PM MST FRI JAN 3 2014/
SHORT TERM...UPPER TROUGH STILL MOVING INTO NORTHERN GREAT
BASIN...BEGINNING TO SEE SOME INCREASE IN MOISTURE ACROSS THE
MOUNTAINS...THOUGH LOOKS TO BE ABOVE MOUNTAIN TOP. NO
PRECIPITATION CURRENTLY ACROSS MOUNTAINS...CLOSEST ACROSS
SOUTHWEST WYOMING AND NORTHERN UTAH. WINDS A BIT GUSTY IN AND NEAR
FOOTHILLS AND ACROSS THE HIGHER MOUNTAINS WITH MIXING AND
INCREASING NORTHWEST FLOW ALOFT AHEAD OF TROUGH. WESTERLY WINDS
HAVE SPREAD AS FAR EAST AS DIA WHICH HELPED TO WARM TEMPERATURES
TO NEAR 60. TROUGH WILL CONTINUE TO MOVE ACROSS THE NORTHERN GREAT
BASIN SOUTHWARD TOWARD COLORADO THIS EVENING AND INTO WESTERN
COLORADO OVERNIGHT. FLOW ALOFT TO BECOME A BIT MORE WESTERLY WITH
INCREASING MOISTURE ACROSS MOUNTAINS. OROGRAPHICS WILL IMPROVE BY
03Z ALONG WITH INCREASING MID LEVEL QG ASCENT AS JET SAGS
SOUTHWARD TOWARD COLORADO. SHOULD SEE SOME SNOW BEGIN TO DEVELOP
BY THE EVENING...ESPECIALLY ACROSS ZONE 31...THEN GRADUALLY BECOME
WIDESPREAD THROUGH THE EVENING WITH IMPROVING OROGRAPHICS AND
LIFT. MODELS SHOW AN INITIAL SHORTWAVE MOVING ACROSS THE MOUNTAINS
AROUND 06Z...WHICH WILL HELP WITH THE SNOWFALL. ALSO THE
APPROACHING JET WILL PROVIDE ADDITIONAL VERTICAL MOTION. GUSTY
WINDS WILL CREATE AREAS OF BLOWING SNOW BY MIDNIGHT...ESPECIALLY
ACROSS THE HIGHER MOUNTAIN PASSES. CURRENT HILITES STILL LOOK
REASONABLE...WITH THE HEAVIER AMOUNTS ACROSS ZONE 31. DID DELAY
THE ONSET OF THE ADVISORIES FOR ZONES 30..32..33 AND 34 UNTIL 03Z
BASED ON CURRENT CONDITIONS. ACROSS FOOTHILLS AND PLAINS...GUSTY
WINDS WILL PERSIST INTO THE EVENING IN AND NEAR FOOTHILLS BEFORE
DECREASING. COLD FRONT ASSOCIATED WITH THE UPPER TROUGH STILL
EXPECTED TO MOVE OUT OF WYOMING AROUND 06Z AND ACROSS THE DENVER
AREA BY 09Z. UPSLOPE WILL THEN DEVELOP AROUND 12Z. LOW LEVEL
MOISTURE TO GRADUALLY INCREASE WITH A CHANCE OF LIGHT SNOW IN AND
NEAR THE FOOTHILLS BY MORNING AS LIFT INCREASES. ON
SATURDAY...UPPER TROUGH WILL MOVE ACROSS THE AREA THROUGH THE DAY.
THE COMBINATION OF GOOD OROGRAPHICS AND MID LEVEL QG ASCENT WITH
JET IN VICINITY WILL CONTINUE TO PROVIDE SNOW FOR THE MOUNTAINS.
WILL CONTINUE WITH THE CURRENT HILITES THROUGH THE AFTERNOON. FOR
FOOTHILLS AND PLAINS...INCREASING UPSLOPE AND MID LEVEL ASCENT
WILL BRING A DECENT SHOT OF SNOW TO MOST LOCATIONS...MAINLY IN AND
NEAR FOOTHILLS. LATEST MODELS STILL SHOWING AMOUNTS IN THE 1 TO 4
INCH RANGE. NAM ON THE LOW END...GFS THE HIGHER END ACROSS THE
DENVER AREA SOUTH OVER THE PALMER DIVIDE. THERE IS STILL SOME
CHANCE FOR A BAND OF HEAVIER SNOW SETTING UP SOMEWHERE ACROSS THE
AREA BY THE AFTERNOON AND COULD HELP PRODUCE MORE SNOW. FOR NOW
WILL CONTINUE WITH THE LOWER AMOUNTS AND WILL WAIT TO SEE WHAT
DEVELOPS BEFORE ISSUING ANY ADVISORIES. AIRMASS TO BE COLDER...
WITH TEMPERATURES STRUGGLING TO GET TO THE MIDDLE 20S ACROSS
PLAINS.
LONG TERM...THE AMS WILL BECOME INCREASINGLY SUBSIDENT SATURDAY
NIGHT AS THE STORM SYSTEM MOVES TO THE EAST. A STRONG
NORTHWESTERLY FLOW WILL BE OVER THE STATE ON SUNDAY WITH THE UPPER
LEVEL JETSTREAM OVER COLORADO. A WEAK DISTURBANCE EMBEDDED IN THE
FLOW ALOFT WILL BRUSH ACROSS NORTHEAST COLORADO AROUND 00Z MONDAY.
WITH THE JET OVERHEAD...THERE IS THE POTENTIAL FOR SOME BANDED
SNOWFALL OVER THE NORTHEAST PLAINS...BUT MDLS NOT DEVELOPING MUCH
QPF AT THIS TIME SO WL STICK TO SLGT CHC POPS. IN THE MOUNTAINS
AND FOOTHILLS...GUSTY NORTHWEST WINDS SO WL ADD AREAS OF BLOWING
SNOW TO THE GRIDS. OVERALL SNOW AMOUNTS WILL BE LIGHT IN THE
MOUNTAINS DUE TO INCREASING STABILITY. A SECONDARY SURGE OF COLD
AIR SUNDAY EVENING...WL KEEP THE NORTHEAST PLAINS LOCKED IN THE
FREEZER THROUGH MONDAY. THE FLOW ALOFT WILL WEAKEN AND BECOME MORE
WESTERLY BY TUESDAY AS A RIDGE OF HIGH PRESSURE BUILDS IN FROM
THE WEST. TEMPERATURES WILL MODIFY THROUGH MID WEEK. A WEAK SYSTEM
MAY MOVE ACROSS COLORADO ON WEDNESDAY BUT SNOWFALL WILL LIKELY BE
CONFINED TO THE MOUNTAIN AREAS. IT WILL BE DRY AGAIN ON THURSDAY
WITH A SHORT WAVE RIDGE OVER COLORADO...FOLLOWED BY ANOTHER
POTENTIAL TROUGH THURSDAY NIGHT INTO FRIDAY. FOR NOW WL KEEP THE
MENTION OF SNOW CONFINED TO THE MOUNTAINS FOR THE END OF NEXT
WEEK.
AVIATION...WESTERLY WINDS CONTINUE ACROSS AREA AIRPORTS...WITH
GUSTS TO 35 KTS AT BJC. WINDS STILL EXPECTED TO GRADUALLY WEAKEN
THROUGH THE EVENING. LATEST RAP INDICATING WINDS SHIFTING TO THE
NORTHWEST BY 02Z. THERE IS A CHANCE THAT DRAINAGE WINDS COULD
DEVELOP AT KDEN AND KAPA DURING THE EVENING BEFORE SHIFTING TO THE
NORTHWEST AFTER 06Z. WILL TREND THE TAFS IN THAT DIRECTION.
MOISTURE TO GRADUALLY INCREASE THROUGH EVENING AND
OVERNIGHT...WITH CEILINGS ABOVE 10000 FEET AGL. FRONT STILL
EXPECTED TO MOVE ACROSS THE DENVER AREA AROUND 09Z WITH GUSTY
NORTHERLY WINDS. CEILINGS WILL GRADUALLY LOWER AS UPSLOPE DEVELOPS
BY 12Z ALONG WITH AREAS OF LIGHT SNOW. THE SNOW WILL CONTINUE
THROUGH THE DAY SATURDAY WITH IFR CONDITIONS PREVAILING.
CONDITIONS TO GRADUALLY IMPROVE AFTER 00Z AS UPSLOPE WEAKENS. SNOW
ACCUMULATION OF 2 TO 4 INCHES STILL EXPECTED FOR AREA
AIRPORTS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR COZ033-034.
WINTER WEATHER ADVISORY UNTIL 5 PM MST SATURDAY FOR COZ030-032.
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ031.
&&
$$
SHORT TERM...ENTREKIN
LONG TERM....COOPER
AVIATION...RTG
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
951 AM MST THU JAN 2 2014
.UPDATE...
&&
.SHORT TERM...OVERALL...CURRENT FORECASTS LOOK ON TRACK. SHORT
WAVE RIDGE TO BUILD ACROSS REGION TODAY WITH WEAKENING NORTHWEST
FLOW ALOFT. WEAK MID LEVEL DISTURBANCE MOVING ACROSS NORTHERN
WYOMING SPREADING SOME MID LEVEL MOISTURE INTO NORTHWEST COLORADO
AT THIS TIME. LATEST SPATIAL CROSS SECTIONS SHOW THIS MOISTURE
MOVING INTO MOUNTAINS DURING THE AFTERNOON AND EVENING. WILL ADD A
BIT MORE CLOUD TO THE SKY GRIDS. NO OTHER CHANGES AT THIS TIME.
.AVIATION...CURRENT TAF TRENDS LOOK ON TRACK. WEAK SOUTHERLY
GRADIENT ACROSS AREA. WINDS A BIT MORE SOUTHWEST AT KDEN...BUT LESS
THAN 8 KTS. LATEST MODELS...INCLUDING THE RAP AND HRRR...STILL
SHOWING A COUNTERCLOCKWISE SHIFT IN THE WINDS ACROSS THE AREA
AIRPORTS THROUGH THE MORNING...WITH SOUTHEAST WINDS THROUGH 00Z.
THEN A RETURN TO SOUTHERLY DURING EVENING AS DRAINAGE DEVELOPS.
VFR TO CONTINUE THROUGH FRIDAY WITH INCREASING MID AND HIGH LEVEL
MOISTURE AFTER 15Z. WAVE CLOUD COULD DEVELOP ALONG FOOTHILLS WITH
CEILINGS AROUND 12000 FEET AT KBJC.
&&
.PREV DISCUSSION... /ISSUED 325 AM MST THU JAN 2 2014/
SHORT TERM...DRY AIR HAS MOVED OVER THE STATE AS NORTHWEST FLOW
ALOFT CONTINUES ALONG WITH SOME SHORT WAVE RIDGING EXPECTED. WINDS
ALOFT SHOULD BE DECREASING THROUGH TODAY AS THEY TRANSITION TO A
LITTLE MORE WESTERLY LATE IN THE AFTERNOON. AT THE SURFACE...
PRESSURE GRADIENTS WILL BE RELAXING THROUGH THE DAY AS A WEAK LEE
TROUGH OF LOW PRESSURE REMAINS OVER THE I-25 CORRIDOR. SKIES WILL
BE SUNNY THROUGH MOST OF THE DAY WITH LOW AND MID LEVEL
TEMPERATURES SUPPORTIVE OF AFTERNOON HIGHS IN THE MID 40S TO LOWER
50S. SOME HIGH LEVEL CLOUDINESS WILL MOVE OVERHEAD TONIGHT WHICH
WILL HELP TO KEEP LOW TEMPERATURES A BIT WARMER THAN WHAT WE SAW
THIS MORNING. ALL IN ALL A RATHER BENIGN DAY...WEATHERWISE.
LONG TERM...INCREASING WNW FLOW ALOFT WILL BE OVER THE AREA ON FRI
IN ADVANCE OF AN UPPER LEVEL TROUGH WHICH WILL AFFECT THE RGN
LATE FRI NIGHT INTO SAT. GUSTY WINDS WILL OCCUR IN THE MTNS AND
FOOTHILLS THRU THE DAY WITH SOME POTENTIAL FOR HIGH WINDS LATE FRI
AFTN INTO FRI EVENING AS MTN WAVE DEVELOPS AND AXIS OF STRONGER
UPPER LEVEL WINDS MOVES INTO THE AREA. MEANWHILE WITH WNW LOW LVL
WINDS DOWNSLOPE COMPONENT WILL ALLOW FOR HIGHS TO RISE INTO THE
50S OVER NERN CO WITH LOWER 60S IN THE DENVER AREA.
FOR LATE FRI NIGHT INTO SAT THE UPPER LEVEL TROUGH WILL MOVE
ACROSS THE AREA ALONG WITH A STG CDFNT. WITH INCREASING MOISTURE
IN THE MTNS AND FAVORABLE OROGRAPHICS SNOW SHOULD DEVELOP FRI
NIGHT AND CONTINUE THRU SAT WITH ADVISORY AMOUNTS LIKELY. AT
LOWER ELEVATIONS UPSLOPE FLOW WILL DEVELOP LATE FRI NIGHT INTO SAT
BEHIND THE STG CDFNT. AS THE UPPER LEVEL TROUGH MOVES ACROSS
ALONG WITH SOME MID LVL QG ASCENT SHOULD SEE A GOOD CHANCE OF SNOW
ESPECIALLY IN THE 12Z-18Z TIMEFRAME. WITH PLACEMENT OF UPPER LEVEL
JET MAY SEE SOME BANDED PCPN AS WELL. HIGHS ON SAT WILL OCCUR
EARLY IN THE DAY WITH READINGS STEADY IN THE 20S MUCH OF THE DAY
OVER THE PLAINS.
BY SAT NIGHT INTO SUN STG NWLY FLOW ALOFT WILL BE OVER THE AREA WITH
A DECREASE IN MOISTURE AND WEAK UPSLOPE FLOW. WILL LIKELY SEE SOME
ADDITIONAL LIGHT SNOW IN THE MTNS WITH GUSTY WINDS. OVER NERN CO IT
LOOKS MAINLY DRY ON SUN WITH HIGHS IN THE 25 TO 30 DEGREE RANGE. BY
LATE IN THE AFTN INTO SUN EVENING ANOTHER SHOT OF COLD AIR WILL MOVE
INTO NERN CO WITH SOME UPSLOPE FLOW WHICH COULD LEAD TO A CHC OF
LIGHT SNOW ESPECIALLY OVER THE PLAINS.
ON MON CROSS-SECTIONS SHOW A DRY AND COLD AIRMASS OVER THE RGN.
HIGHS ON MON OVER NERN CO LOOK TO BE IN THE UPPER TEENS TO MID 20S.
BY TUE THE FLOW ALOFT WILL BECOME MORE WLY WITH SOME MODERATION IN
TEMPS AS HIGHS RISE BACK INTO THE 30S ACROSS NERN CO. OUTSIDE OF A
SLIGHT CHC OF SNOW IN THE MTNS IT LOOKS DRY. BY WED A WEAK UPPER
LEVEL TROUGH MAY MOVE ACROSS THE AREA BRINGING A CHC OF SNOW TO THE
MTNS. OVER NERN CO WILL KEEP IT DRY WITH TEMPS NEAR SEASONAL
NORMALS.
AVIATION...NO AVIATION IMPACTS EXPECTED OVER THE NEXT 24 HOURS.
CEILINGS AND VISIBILITIES WILL BE UNRESTRICTED. SURFACE WINDS WILL
BE OUT OF THE SOUTH TO SOUTHEAST AT 10-14 KNOTS OR LESS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....RPK
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS PUEBLO CO
419 AM MST THU JAN 2 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 419 AM MST THU JAN 2 2014
QUIET WEATHER IS EXPECTED IN THE SHORT TERM ASIDE FROM SOME VEXING
STRATUS THIS MORNING ALONG THE SOUTHERN SLOPES OF THE PALMER DIVIDE
WHERE LIGHT UPSLOPE IS WORKING ON SOME SHALLOW LOW LEVEL MOISTURE.
WINDS ALOFT ARE PROGGED TO INCREASE OUT OF THE NORTHWEST LATER THIS
MORNING WHICH SHOULD ERODE THE LOW CLOUDS EASTWARD AND DISSIPATE
THEM ENTIRELY BY MID MORNING. OTHERWISE DRY WEATHER IS EXPECTED
TODAY WITH SOME INCREASING HIGH CLOUDINESS INVADING IN THE AFTERNOON
AS WEAK SHORTWAVE CURRENTLY OVER ID DROPS TO THE SOUTHEAST ACROSS CO
THIS EVENING. HIGH TEMPERATURES TODAY SHOULD WARM OVER THOSE OF
YESTERDAY FOR THE PLAINS...EXCEPT IN THE SNOW COVERED SAN LUIS
VALLEY WHERE LIGHT WINDS SHOULD KEEP TEMPERATURES IN THE 20S
AGAIN.
FOR TONIGHT...LEE TROF SHOULD KEEP TEMPS IN THE LOWER 30S FOR
OVERNIGHT LOWS ALONG THE LOWER EASTERN SLOPES OF THE SE MTS/ADJACENT
PLAINS. ELSEWHERE CLEARING SKIES SHOULD ALLOW TEMPERATURES TO DROP
INTO THE TEENS AND 20S WITH NEGATIVE SINGLE DIGITS ACROSS THE SAN
LUIS VALLEY. -KT
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 419 AM MST THU JAN 2 2014
.FRIDAY...WARMING ALOFT CONTINUES AHEAD OF THE SHORTWAVE
APPROACHING FROM THE NORTHWEST. TEMPERATURES AT 700MB ARE FORECAST
TO BE AROUND +2C. SUSPECT THERE WILL BE ENOUGH MIXING FOR HIGHS TO
BE AROUND 60F OVER MUCH OF THE PLAINS. TEMPERATURES WILL ALSO BE
RELATIVELY MILD FOR THE MOUNTAINS. IN THE SAN LUIS
VALLEY...BELIEVE THAT APPROACHING TROUGH WILL NOT ALLOW FOR MIXING
DURING THE DAY...AND HAVE TEMPERATURES BELOW GUIDANCE...WHICH HAS
FREQUENTLY OCCURRED ON DAYS WITH LITTLE MIXING.
.SATURDAY...UPPER TROUGH MOVES INTO THE STATE FROM THE
NORTHWEST...WITH A COLD FRONT MOVING IN FROM THE NORTH OVER THE
PLAINS AND EASTERN MOUNTAINS. TRENDED TOWARDS THE MORE MOIST GFS
AND EC AS THE NAM HAS TENDED TO BE TOO DRY IN THE PAST FEW WEEKS.
NORTHWEST FLOW ALOFT FAVORS SNOWFALL OVER THE MOUNTAINS OF LAKE
AND CHAFFEE COUNTIES. CURRENT GRIDS HAVE SNOWFALL AMOUNTS
APPROACHING ADVISORY CRITERIA...AND WOULD NOT BE TOO SURPRISED IF
AN ADVISORY IS NEEDED FOR SATURDAY. FURTHER EAST...MODELS
CONSENSUS IS TO HAVE THE FRONTAL PASSAGE SOMETIME DURING THE
MORNING. GFS AND EC CONTINUE TO SUGGEST THE POTENTIAL FOR SOME
LIGHT SNOW DURING THE AFTERNOON WHILE THE NAM IS MUCH DRIER.
LEANED SLIGHTLY TOWARDS THE WETTER GFS/EC SOLUTION WHICH HAS THE
TROUGH SLIGHTLY FURTHER SOUTH. THERE COULD BE A BRIEF PERIOD OF
UPGLIDE AROUND 600MB OVER THE LOWER LEVEL COLD AIR. TEMPERATURES
AT THE UPGLIDE LEVEL WILL BE AROUND -15C...WHICH IS IN THE PRIME
REGION FOR DENDRITIC GROWTH. SUSPECT ANY ACCUMULATIONS WILL BE ON
THE LIGHT SIDE...MAYBE AN INCH OR TWO AT MOST. CURRENT GRIDS ONLY
HAVE SCATTERED TO HIGH SCATTERED POPS. IN THE SAN LUIS
VALLEY...DISTURBANCE COULD RESULT IN MIXING IN THE VALLEY...BUT
AIR ALOFT WILL BE COLD WHICH WOULD MINIMIZE THE AMOUNT OF WARMING.
.SUNDAY AND MONDAY...NEXT DISTURBANCE APPROACHES THE REGION FROM
THE NORTHWEST ON SUNDAY. TROUGH WILL BE FURTHER EAST THAN THE TROUGH
ON SATURDAY...SO ANTICIPATE LESS SNOWFALL. ANOTHER COLD FRONT WILL
MOVE ACROSS THE PLAINS AND EASTERN MOUNTAINS DURING THE DAY ON
SUNDAY. MAIN QUESTION IS HOW COLD IT WILL BE SUNDAY NIGHT AND
MONDAY. THE COLDEST AIR WILL STAY TO THE NORTHEAST OF THE
REGION...AND THE EC HAS THE COLD AIR MOVING SLIGHTLY FURTHER WEST
THAN THE GFS. GRIDS HAVE A COMPROMISE BETWEEN THE GFS AND EC WITH
HIGHS IN THE 20S OVER THE PLAINS. OVER THE MOUNTAINS...SOME
WARMING COULD OCCUR DURING MONDAY AFTERNOON AS THE LOW LEVEL COLD
AIR WILL BECOME SHALLOWER.
.TUESDAY AND WEDNESDAY....COLD AIR WILL MOVE EAST ON TUESDAY...AND FLOW
ALOFT WILL BECOME WESTERLY WITH WARMING ALOFT. ANTICIPATE A
WARMING TREND TO DEVELOP ON TUESDAY WITH THE GREATEST AMOUNT OF
WARMING OVER AND NEAR THE MOUNTAINS. BY WEDNESDAY...THE NEXT
DISTURBANCE WILL MOVE INTO THE REGION. CURRENTLY...THE TROUGH
APPEARS TO BE WEAK...AND ONLY HAVE ISOLATED TO SCATTERED POPS IN
THE GRIDS. --PGW--
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 419 AM MST THU JAN 2 2014
IFR TO LIFR STRATUS HAS DEVELOPED OVER KCOS AND KPUB...WITH VIS
DROPPING TO AROUND 1 1/2 SM AT KPUB AT TIMES IN FOG IN THE PAST
HOUR. THIS IS DUE TO LIGHT UPSLOPE WINDS BEHIND YESTERDAY`S COLD
FRONT. FORECAST MODELS HAVE DRY WESTERLY WINDS ALOFT INCREASING
LATER THIS MORNING WITH STRATUS AND FOG PUSHING EASTWARD THOUGH
TIMING IN MODELS VARIES SIGNIFICANTLY...PUTTING UNCERTAINTY HIGH AS
TO TIMING THE STRATUS OUT OF BOTH TERMINALS. LATEST RUC13 SUGGESTS
AROUND 14-15Z WITH KCOS BREAKING OUT FIRST...WHICH SEEMS
REASONABLE...BUT WILL NEED TO MONITOR FOR POTENTIAL CHANGES.
MEANWHILE DRY AIR ALOFT HAS KEPT FOG FROM FORMING AT KALS THUS FAR.
AFTER 15Z...EXPECT VFR CONDITIONS TO PREVAIL AT THE TERMINALS THOUGH
SOME IFR TO LIFR STRATUS COULD LINGER TO 17Z TO THE EAST OF KCOS AND
KPUB. OTHERWISE WINDS SHOULD REMAIN LIGHT WITH SPEEDS UNDER 12 KTS.
SOME HIGH CLOUDINESS WILL INCREASE OVER THE AREA DURING THE
AFTERNOON. DO NOT ANTICIPATE THE RETURN OF STRATUS OR FOG TONIGHT
AT THE TERMINALS THOUGH KALS ALWAYS CARRIES A LOW PROBABILITY OVER
THE PERSISTENT SNOW COVER. FOR NOW THREAT APPEARS TOO LOW AT THIS
POINT TO WARRANT MENTION IN THE KALS TAF. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KT
LONG TERM...PGW
AVIATION...KT
AREA FORECAST DISCUSSION
NWS ALBANY NY
1224 PM EST THU JAN 2 2014
.SYNOPSIS...
LOW PRESSURE MOVING ACROSS THE OHIO VALLEY TODAY WILL
REFORM OFF THE MID ATLANTIC COAST THIS EVENING...AND MOVE OFF THE
NORTHEAST COAST TONIGHT INTO TOMORROW. THIS WILL ALLOW FOR A
PROLONGED PERIOD OF SNOW ACROSS THE REGION THROUGH TOMORROW
MORNING. VERY COLD AIR WILL ACCOMPANY THIS SNOW...ESPECIALLY ACROSS
NORTHERN AND HIGH TERRAIN AREAS...WITH DANGEROUSLY COLD WIND CHILL
VALUES. DRY...BUT CONTINUED COLD WEATHER WILL BE IN PLACE ON
SATURDAY...BEFORE ANOTHER STORM THREATENS THE REGION FOR SUNDAY
INTO MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 845 AM EST...A BAND OF MODERATE SNOW HAS SET UP ACROSS THE
CAPITAL REGION...MOHAWK VALLEY REGION...EXTENDING INTO THE
SCHOHARIE VALLEY AND NE CATSKILLS...AND ALSO INTO SOUTHERN VT AND
THE NORTHERN BERKSHIRES. THIS BAND APPEARS TO BE IN ASSOCIATION
WITH STRONG 850-700 MB FRONTOGENETICAL FORCING...COMBINED WITH
ISENTROPIC LIFT. THE LATEST RUC13 SUGGESTS THAT THIS BAND OF MID
LEVEL FORCING...AND HEAVIER SNOWFALL...SHOULD SLOWLY LIFT
NORTHWARD LATER THIS MORNING INTO THE AFTERNOON HOURS...WITH THE
STEADIEST SNOWFALL SHIFTING INTO THE NORTH SIDE OF THE MOHAWK
VALLEY...THE LAKE GEORGE/SARATOGA REGION...AND SOUTHERN VT. IT IS
POSSIBLE THAT AREAS TO THE SOUTH...INCLUDING THE CAPITAL
REGION...EXPERIENCE A BREAK...OR AT LEAST SOME PERIODS OF LIGHTER
SNOWFALL...FOR MUCH OF THE AFTERNOON. WHERE THE BAND SETS UP...AN
ADDITIONAL 3-6 INCHES ARE EXPECTED THROUGH LATE AFTERNOON. FURTHER
SOUTH...GENERALLY 1-3 INCHES ARE EXPECTED...WITH EVEN LESS
POSSIBLE ACROSS PORTIONS OF THE MID HUDSON VALLEY AND NW CT REGION.
TEMPS HAVE FALLEN MUCH LOWER THAN ANY GUIDANCE SUGGESTED...WITH
CURRENT TEMPS GENERALLY RANGING FROM ZERO TO 5 ABOVE IN VALLEY
AREAS AND POINTS NORTH AND WEST...WITH SOME SINGLE DIGITS BELOW
ZERO ACROSS THE SOUTHERN ADIRONDACKS. FURTHER SOUTH AND
EAST...TEMPS RANGE FROM THE SINGLE DIGITS TO MID TEENS. WE EXPECT
TEMPS TO HOLD NEARLY STEADY THROUGH THIS AFTERNOON...ALTHOUGH
SHOULD FALL SEVERAL MORE DEGREES ACROSS PORTIONS OF THE MID HUDSON
VALLEY REGION AS THE COLD DENSE AIR CONTINUES TO SETTLE SOUTHWARD.
SO...EXPECT MOST VALLEY AREAS TO RANGE BETWEEN ZERO AND 10
ABOVE...WITH THE SOUTHERN ADIRONDACKS AND HIGHER ELEVATIONS ACROSS
WESTERN NEW ENGLAND POSSIBLY HOLDING AROUND ZERO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
BY THIS EVENING...PRESSURE FALLS WILL BEGIN OCCURRING OFF THE MID
ATLANTIC COAST...AS A NEW AREA OF LOW PRESSURE FORMS OFF THE COAST
OF VIRGINA. THIS SURFACE LOW WILL THEN TRACK NORTHEASTWARD WELL
OFF THE COAST OF THE NORTHEASTERN US. ALTHOUGH THE SURFACE LOW
WON/T BE TOO CLOSE TO OUR REGION...IT WILL STILL BE ABLE TO THROW
SOME ADDITIONAL ATLANTIC MOISTURE BACK OUR WAY. WITH THE STRONG
UPPER TROUGH PASSING OVERHEAD...STEADY SNOWFALL LOOKS TO OCCUR
ACROSS THE ENTIRE REGION...WITH THE HEAVIEST AMOUNTS ACROSS HIGH
TERRAIN AREAS OF THE SOUTHERN AND EASTERN PARTS OF THE CWA.
WITH CONTINUED VERY HIGH SNOW TO LIQUID RATIOS...ADDITIONAL LIGHT TO
MODERATE SNOW ACCUMULATIONS ARE EXPECTED OVERNIGHT...ALLOWING FOR
STORM TOTAL ACCUMULATION OF 6 TO 12 INCHES OVER MUCH OF THE REGION
BY TOMORROW MORNING. SLIGHTLY LOWER AMOUNTS ARE EXPECTED OVER THE
WESTERN ADIRONDACKS WHERE LESS QPF IS EXPECTED...AND A FEW SPOTS
IN THE HIGH TERRAIN OF THE CATSKILLS...GREENS...AND BERKSHIRES MAY
SEE CLOSE 15 INCHES IN TOTAL. STEADY SNOW LOOKS TO TAPER OFF
AROUND SUNRISE TOMORROW.
WITH THE INCREASING PRESSURE GRADIENT DUE TO THE DEVELOPING LOW
PRESSURE...N-NE WINDS WILL PICK UP LATE TONIGHT INTO TOMORROW
MORNING. DUE TO THE VERY LIGHT AND FLUFFY SNOW...THIS WILL ALLOW
FOR BLOWING AND DRIFTING OF SNOWFALL. TEMPS WILL BE VERY COLD
TONIGHT WITH TEMPS RANGING FROM 25 BELOW ZERO OVER THE ADIRONDACKS
TO 10 ABOVE OVER THE MID HUDSON VALLEY AND NW CT. WITH THE GUSTY
WINDS...WIND CHILL VALUES WILL BE AS LOW AS -25 TO -40 OVER THE
ADIRONDACKS...AND -10 TO -25 ELSEWHERE. BECAUSE OF THIS...A WIND
CHILL WARNING HAS BEEN ISSUED FOR THE ADIRONDACKS...AND WIND CHILL
INFORMATION HAS BEEN POSTED IN OUR WINTER STORM WARNING /WSW/ FOR
THE REMAINDER OF THE REGION.
A FEW LINGERING SNOW SHOWERS MAY AFFECT EASTERN AREAS FOR TOMORROW
MORNING...OTHERWISE SOME SUNSHINE SHOULD RETURN BY AFTN. DESPITE
THE SUN RETURNING...IT WILL REMAIN VERY COLD WITH TEMPS IN THE
SINGLE DIGITS. SOME AREAS IN THE ADIRONDACKS AND WESTERN MOHAWK
VALLEY MAY NOT EVEN RISE ABOVE ZERO DURING THE DAY FRIDAY.
HIGH PRESSURE WILL MOVE OVER THE REGION FRIDAY NIGHT...ALLOWING
SKIES TO BE MAINLY CLEAR FOR MUCH OF THE REGION. WINDS WILL
LIGHTEN UP...AND WITH THE FRESH DEEP SNOW PACK...A VERY COLD NIGHT
IS IN STORE FOR FRIDAY NIGHT. THE ENTIRE CWA LOOKS TO DROP BELOW
ZERO...WITH TEMPS IN THE CAPITAL REGION DOWN AROUND -8 TO -15.
TEMPS AROUND GLENS FALLS AND IN THE ADIRONDACKS WILL BE -20 TO
-25. BEFORE WINDS LIGHTEN UP...ADDITIONAL WIND CHILL HEADLINES MAY
BE NEEDED FOR FRI NIGHT/EARLY SAT...AND THIS WILL BE MENTIONED IN
THE HWO. EVEN WITHOUT WIND...IT WILL BE BRUTALLY COLD ACROSS THE
WHOLE AREA...AND PRECAUTIONS WILL NEED TO BE TAKEN TO PREVENT
DAMAGE TO HOMES...BUSINESSES...AND LIVESTOCK.
HIGH PRESSURE WILL CONTINUE TO ALLOW FOR QUIET AND DRY WEATHER ON
SATURDAY. TEMPS WILL REMAIN BELOW NORMAL...BUT WILL MODERATE
SOMEWHAT FROM THE BRUTALLY COLD LEVELS OF FRI/FRI NIGHT...AS THE
HIGH PRESSURE AREA BEGINS TO SHIFT EASTWARD. MAX TEMPS ON SAT AFTN
LOOK TO REACH THE TEENS TO MID 20S ACROSS THE AREA.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ANOTHER STORM SYSTEM FOR SUNDAY NIGHT INTO MONDAY WHICH SHOULD BRING
SNOW...SLEET...FREEZING RAIN AND RAIN TO THE AREA.
WE START OUT THE PERIOD A WITH A DEEP TROUGH DIGGING IN ACROSS THE
CENTRAL CONUS WHILE A STRONG UPPER LOW DROPS SOUTHWARD TOWARD THE
GREAT LAKES REGION. AT THE SURFACE...A LOW PRESSURE SYSTEM OVER THE
GREAT LAKES REGION WILL MOVE NORTHEASTWARD TOWARD HUDSON BAY CANADA
WITH ITS COLD FRONT TRAILING OFF TO THE SOUTHWEST ACROSS THE PLAINS
INTO THE DEEP SOUTH. THIS SYSTEM WILL NOT DIRECTLY IMPACT OUR
REGION. HOWEVER AS A POTENT SHORT WAVE ROTATING THROUGH THE BASE OF
THE DEEP TROUGH SURFACE LOW WILL SPIN UP ON THE COLD FRONTAL
BOUNDARY. IT IS THIS SYSTEM THAT WILL BRING A WINTRY MESS TO THE OUR
REGION TO CLOSE OUT THE WEEK AND START THE NEW WORK WEEK.
THERE IS MUCH UNCERTAINTY IN THE FORECAST AS MODEL DIFFERENCES
CONTINUE...HOWEVER THE ECMWF AND GFS HAVE TRENDED TOWARD EACH OTHER.
THE ECMWF IS STILL TRACKING THE LOW ACROSS THE OHIO VALLEY THEN
SAINT LAWRENCE VALLEY WHILE THE GFS TAKES THE LOW ACROSS NEW YORK
AND NEW ENGLAND SUNDAY NIGHT INTO MONDAY. THERE IS A WIDE SPREAD IN
THE GFSENSEMBLE TRACKS WITH THE OPERATIONAL GFS ON THE WEST SIDE OF
THE SOLUTIONS AND THE ECMWF MORE IN LINE WITH THE MOST WESTERN
MEMBERS. THE EXACT TRACK OF THE LOW WILL DETERMINE THE THERMAL
PROFILE AND THEREFORE P-TYPES AS WARMER AIR SURGES IN AHEAD OF THE
SYSTEM. HAVE FOLLOWED GUIDANCE FROM THE WEATHER PREDICTION CENTER
WHICH USED A BLENDED MODEL APPROACH.
BASED ON THIS TRACK AND TIMING TEMPERATURES SHOULD PEAK IN THE
MONDAY MORNING THEN FALL DURING THE AFTERNOON WITH THE PASSAGE OF
THE SYSTEM. DID UNDERCUT TEMPERATURES AS IT WILL BE HARD TO WARM UP
WITH WIDESPREAD DEEP FRESH SNOWPACK ACROSS AREA. AREAS MAINLY TO THE
EAST OF THE HUDSON RIVER VALLEY SHOULD WARM INTO THE LOWER/MID 40S.
A STRONG 850 MB JET OF 40 TO 60 KNOTS WILL BRING WARMER AIR IN ALOFT
AND THE STAGE WILL BE SET FOR SNOW...SLEET...FREEZING RAIN AND RAIN
ESPECIALLY LATE SUNDAY NIGHT INTO MONDAY MORNING. WILL MENTION STORM
IN OUR HAZARDOUS WEATHER OUTLOOK. THE PRECIPITATION SHOULD TAPER OFF
BY MONDAY EVENING WITH IT CHANGING BACK TO SNOW POSSIBLY BEFORE
ENDING AS COLD AIR IS USHERING IN. CONDITIONS WILL BECOME FAVORABLE
FOR LAKE EFFECT SNOWS IN THE WAKE OF THE SYSTEM.
COLDER AIR WILL SURGE IN BY 12Z/TUESDAY 850 MB TEMPERATURES ARE
EXPECTED TO DROP TO AROUND -25C...WITH SURFACE TEMPERATURES
BOTTOMING OUT INTO THE SINGLE DIGITS BY SUNRISE TUESDAY. DAYTIME
HIGHS TUESDAY AND WEDNESDAY WILL BE SIMILAR TO WHAT OUR NORMAL LOWS
SHOULD BE. WINDS WILL BE BRISK TUESDAY ONLY MAKING IT COLDER. COULD
HAVE ISSUES WITH WIND CHILLS AGAIN TUESDAY NIGHT INTO WEDNESDAY
MORNING.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
SNOW WILL CONTINUE THROUGH MUCH OF THE TAF PERIOD WNDING AT 18Z FRIDAY.
THE SNOW WILL COME DOWN HEAVIEST THIS EVENING AS AREA OF LOW
PRESSURE MOVES OFF THE MID ATLANTIC COAST AND STRENGTHENS TONIGHT.
IFR CONDITIONS WILL LOWER TO LIFR FOR THE EVENING WITH THE HEAVIER
SNOW. AN IMPROVEMENT TO MVFR IS EXPECTED TO OCCUR LATE IN THE
PERIOD AS THE SNOW LIGHTENS UP.
NORTH TO NORTHEAST WINDS AROUND 10 KNOTS WILL SHIFT MORE TO THE
NORTH AS THE DAY PROGRESSES AND INCREASE IN SPEED AS LOW MOVES OFF
THE MID ATLANTIC COAST AND STRENGTHENS. GUSTS TO AROUND 20 KNOTS ARE
EXPECTED.
OUTLOOK...
FRI NIGHT-SAT NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUN: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN...SLEET.
SUN NIGHT-MON: HIGH OPERATIONAL IMPACT. LIKELY
RA...SN...FZRA...SLEET.
MON NIGHT-TUE: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO WIDESPREAD HYDROLOGIC PROBLEMS ARE EXPECTED OVER THE NEXT FIVE
DAYS.
A STORM SYSTEM WILL BRING SNOW TO THE REGION TODAY THROUGH
TOMORROW MORNING. VERY COLD TEMPERATURES ARE EXPECTED LATE THIS
WEEK...WHICH WILL CONTINUE TO ALLOW RIVER AND LAKE ICE TO FORM AND
THICKEN.
ANOTHER STORM SYSTEM WILL BRING PRECIPITATION TO THE REGION LATE
SUNDAY INTO MONDAY. WITH WARMER AIR EXPECTED ALOFT...PRECIPITATION
WITH THIS SYSTEM WILL BEGIN AS SNOW OR A WINTRY MIX...AND PERHAPS CHANGING
TO RAIN IN SOME AREAS. PRECIPITATION AMOUNTS ARE STILL UNCERTAIN
WITH THIS SYSTEM.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR CTZ001-013.
NY...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR NYZ038>041-043-
047>054-058>061-063>066-082>084.
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR NYZ032-033-
042.
WIND CHILL WARNING FROM 7 PM THIS EVENING TO 11 AM EST FRIDAY
FOR NYZ032-033-042.
MA...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR MAZ001-025.
VT...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS/KL
SHORT TERM...FRUGIS
LONG TERM...IAA
AVIATION...IAA/11
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
859 AM EST THU JAN 2 2014
.SYNOPSIS...
LOW PRESSURE MOVING ACROSS THE OHIO VALLEY TODAY WILL
REFORM OFF THE MID ATLANTIC COAST THIS EVENING...AND MOVE OFF THE
NORTHEAST COAST TONIGHT INTO TOMORROW. THIS WILL ALLOW FOR A
PROLONGED PERIOD OF SNOW ACROSS THE REGION THROUGH TOMORROW
MORNING. VERY COLD AIR WILL ACCOMPANY THIS SNOW...ESPECIALLY ACROSS
NORTHERN AND HIGH TERRAIN AREAS...WITH DANGEROUSLY COLD WIND CHILL
VALUES. DRY...BUT CONTINUED COLD WEATHER WILL BE IN PLACE ON
SATURDAY...BEFORE ANOTHER STORM THREATENS THE REGION FOR SUNDAY
INTO MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 845 AM EST...A BAND OF MODERATE SNOW HAS SET UP ACROSS THE
CAPITAL REGION...MOHAWK VALLEY REGION...EXTENDING INTO THE
SCHOHARIE VALLEY AND NE CATSKILLS...AND ALSO INTO SOUTHERN VT AND
THE NORTHERN BERKSHIRES. THIS BAND APPEARS TO BE IN ASSOCIATION
WITH STRONG 850-700 MB FRONTOGENETICAL FORCING...COMBINED WITH
ISENTROPIC LIFT. THE LATEST RUC13 SUGGESTS THAT THIS BAND OF MID
LEVEL FORCING...AND HEAVIER SNOWFALL...SHOULD SLOWLY LIFT
NORTHWARD LATER THIS MORNING INTO THE AFTERNOON HOURS...WITH THE
STEADIEST SNOWFALL SHIFTING INTO THE NORTH SIDE OF THE MOHAWK
VALLEY...THE LAKE GEORGE/SARATOGA REGION...AND SOUTHERN VT. IT IS
POSSIBLE THAT AREAS TO THE SOUTH...INCLUDING THE CAPITAL
REGION...EXPERIENCE A BREAK...OR AT LEAST SOME PERIODS OF LIGHTER
SNOWFALL...FOR MUCH OF THE AFTERNOON. WHERE THE BAND SETS UP...AN
ADDITIONAL 3-6 INCHES ARE EXPECTED THROUGH LATE AFTERNOON. FURTHER
SOUTH...GENERALLY 1-3 INCHES ARE EXPECTED...WITH EVEN LESS
POSSIBLE ACROSS PORTIONS OF THE MID HUDSON VALLEY AND NW CT REGION.
TEMPS HAVE FALLEN MUCH LOWER THAN ANY GUIDANCE SUGGESTED...WITH
CURRENT TEMPS GENERALLY RANGING FROM ZERO TO 5 ABOVE IN VALLEY
AREAS AND POINTS NORTH AND WEST...WITH SOME SINGLE DIGITS BELOW
ZERO ACROSS THE SOUTHERN ADIRONDACKS. FURTHER SOUTH AND
EAST...TEMPS RANGE FROM THE SINGLE DIGITS TO MID TEENS. WE EXPECT
TEMPS TO HOLD NEARLY STEADY THROUGH THIS AFTERNOON...ALTHOUGH
SHOULD FALL SEVERAL MORE DEGREES ACROSS PORTIONS OF THE MID HUDSON
VALLEY REGION AS THE COLD DENSE AIR CONTINUES TO SETTLE SOUTHWARD.
SO...EXPECT MOST VALLEY AREAS TO RANGE BETWEEN ZERO AND 10
ABOVE...WITH THE SOUTHERN ADIRONDACKS AND HIGHER ELEVATIONS ACROSS
WESTERN NEW ENGLAND POSSIBLY HOLDING AROUND ZERO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
BY THIS EVENING...PRESSURE FALLS WILL BEGIN OCCURRING OFF THE MID
ATLANTIC COAST...AS A NEW AREA OF LOW PRESSURE FORMS OFF THE COAST
OF VIRGINA. THIS SURFACE LOW WILL THEN TRACK NORTHEASTWARD WELL
OFF THE COAST OF THE NORTHEASTERN US. ALTHOUGH THE SURFACE LOW
WON/T BE TOO CLOSE TO OUR REGION...IT WILL STILL BE ABLE TO THROW
SOME ADDITIONAL ATLANTIC MOISTURE BACK OUR WAY. WITH THE STRONG
UPPER TROUGH PASSING OVERHEAD...STEADY SNOWFALL LOOKS TO OCCUR
ACROSS THE ENTIRE REGION...WITH THE HEAVIEST AMOUNTS ACROSS HIGH
TERRAIN AREAS OF THE SOUTHERN AND EASTERN PARTS OF THE CWA.
WITH CONTINUED VERY HIGH SNOW TO LIQUID RATIOS...ADDITIONAL LIGHT TO
MODERATE SNOW ACCUMULATIONS ARE EXPECTED OVERNIGHT...ALLOWING FOR
STORM TOTAL ACCUMULATION OF 6 TO 12 INCHES OVER MUCH OF THE REGION
BY TOMORROW MORNING. SLIGHTLY LOWER AMOUNTS ARE EXPECTED OVER THE
WESTERN ADIRONDACKS WHERE LESS QPF IS EXPECTED...AND A FEW SPOTS
IN THE HIGH TERRAIN OF THE CATSKILLS...GREENS...AND BERKSHIRES MAY
SEE CLOSE 15 INCHES IN TOTAL. STEADY SNOW LOOKS TO TAPER OFF
AROUND SUNRISE TOMORROW.
WITH THE INCREASING PRESSURE GRADIENT DUE TO THE DEVELOPING LOW
PRESSURE...N-NE WINDS WILL PICK UP LATE TONIGHT INTO TOMORROW
MORNING. DUE TO THE VERY LIGHT AND FLUFFY SNOW...THIS WILL ALLOW
FOR BLOWING AND DRIFTING OF SNOWFALL. TEMPS WILL BE VERY COLD
TONIGHT WITH TEMPS RANGING FROM 25 BELOW ZERO OVER THE ADIRONDACKS
TO 10 ABOVE OVER THE MID HUDSON VALLEY AND NW CT. WITH THE GUSTY
WINDS...WIND CHILL VALUES WILL BE AS LOW AS -25 TO -40 OVER THE
ADIRONDACKS...AND -10 TO -25 ELSEWHERE. BECAUSE OF THIS...A WIND
CHILL WARNING HAS BEEN ISSUED FOR THE ADIRONDACKS...AND WIND CHILL
INFORMATION HAS BEEN POSTED IN OUR WINTER STORM WARNING /WSW/ FOR
THE REMAINDER OF THE REGION.
A FEW LINGERING SNOW SHOWERS MAY AFFECT EASTERN AREAS FOR TOMORROW
MORNING...OTHERWISE SOME SUNSHINE SHOULD RETURN BY AFTN. DESPITE
THE SUN RETURNING...IT WILL REMAIN VERY COLD WITH TEMPS IN THE
SINGLE DIGITS. SOME AREAS IN THE ADIRONDACKS AND WESTERN MOHAWK
VALLEY MAY NOT EVEN RISE ABOVE ZERO DURING THE DAY FRIDAY.
HIGH PRESSURE WILL MOVE OVER THE REGION FRIDAY NIGHT...ALLOWING
SKIES TO BE MAINLY CLEAR FOR MUCH OF THE REGION. WINDS WILL
LIGHTEN UP...AND WITH THE FRESH DEEP SNOW PACK...A VERY COLD NIGHT
IS IN STORE FOR FRIDAY NIGHT. THE ENTIRE CWA LOOKS TO DROP BELOW
ZERO...WITH TEMPS IN THE CAPITAL REGION DOWN AROUND -8 TO -15.
TEMPS AROUND GLENS FALLS AND IN THE ADIRONDACKS WILL BE -20 TO
-25. BEFORE WINDS LIGHTEN UP...ADDITIONAL WIND CHILL HEADLINES MAY
BE NEEDED FOR FRI NIGHT/EARLY SAT...AND THIS WILL BE MENTIONED IN
THE HWO. EVEN WITHOUT WIND...IT WILL BE BRUTALLY COLD ACROSS THE
WHOLE AREA...AND PRECAUTIONS WILL NEED TO BE TAKEN TO PREVENT
DAMAGE TO HOMES...BUSINESSES...AND LIVESTOCK.
HIGH PRESSURE WILL CONTINUE TO ALLOW FOR QUIET AND DRY WEATHER ON
SATURDAY. TEMPS WILL REMAIN BELOW NORMAL...BUT WILL MODERATE
SOMEWHAT FROM THE BRUTALLY COLD LEVELS OF FRI/FRI NIGHT...AS THE
HIGH PRESSURE AREA BEGINS TO SHIFT EASTWARD. MAX TEMPS ON SAT AFTN
LOOK TO REACH THE TEENS TO MID 20S ACROSS THE AREA.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ANOTHER STORM SYSTEM FOR SUNDAY NIGHT INTO MONDAY WHICH SHOULD BRING
SNOW...SLEET...FREEZING RAIN AND RAIN TO THE AREA.
WE START OUT THE PERIOD A WITH A DEEP TROUGH DIGGING IN ACROSS THE
CENTRAL CONUS WHILE A STRONG UPPER LOW DROPS SOUTHWARD TOWARD THE
GREAT LAKES REGION. AT THE SURFACE...A LOW PRESSURE SYSTEM OVER THE
GREAT LAKES REGION WILL MOVE NORTHEASTWARD TOWARD HUDSON BAY CANADA
WITH ITS COLD FRONT TRAILING OFF TO THE SOUTHWEST ACROSS THE PLAINS
INTO THE DEEP SOUTH. THIS SYSTEM WILL NOT DIRECTLY IMPACT OUR
REGION. HOWEVER AS A POTENT SHORT WAVE ROTATING THROUGH THE BASE OF
THE DEEP TROUGH SURFACE LOW WILL SPIN UP ON THE COLD FRONTAL
BOUNDARY. IT IS THIS SYSTEM THAT WILL BRING A WINTRY MESS TO THE OUR
REGION TO CLOSE OUT THE WEEK AND START THE NEW WORK WEEK.
THERE IS MUCH UNCERTAINTY IN THE FORECAST AS MODEL DIFFERENCES
CONTINUE...HOWEVER THE ECMWF AND GFS HAVE TRENDED TOWARD EACH OTHER.
THE ECMWF IS STILL TRACKING THE LOW ACROSS THE OHIO VALLEY THEN
SAINT LAWRENCE VALLEY WHILE THE GFS TAKES THE LOW ACROSS NEW YORK
AND NEW ENGLAND SUNDAY NIGHT INTO MONDAY. THERE IS A WIDE SPREAD IN
THE GFSENSEMBLE TRACKS WITH THE OPERATIONAL GFS ON THE WEST SIDE OF
THE SOLUTIONS AND THE ECMWF MORE IN LINE WITH THE MOST WESTERN
MEMBERS. THE EXACT TRACK OF THE LOW WILL DETERMINE THE THERMAL
PROFILE AND THEREFORE P-TYPES AS WARMER AIR SURGES IN AHEAD OF THE
SYSTEM. HAVE FOLLOWED GUIDANCE FROM THE WEATHER PREDICTION CENTER
WHICH USED A BLENDED MODEL APPROACH.
BASED ON THIS TRACK AND TIMING TEMPERATURES SHOULD PEAK IN THE
MONDAY MORNING THEN FALL DURING THE AFTERNOON WITH THE PASSAGE OF
THE SYSTEM. DID UNDERCUT TEMPERATURES AS IT WILL BE HARD TO WARM UP
WITH WIDESPREAD DEEP FRESH SNOWPACK ACROSS AREA. AREAS MAINLY TO THE
EAST OF THE HUDSON RIVER VALLEY SHOULD WARM INTO THE LOWER/MID 40S.
A STRONG 850 MB JET OF 40 TO 60 KNOTS WILL BRING WARMER AIR IN ALOFT
AND THE STAGE WILL BE SET FOR SNOW...SLEET...FREEZING RAIN AND RAIN
ESPECIALLY LATE SUNDAY NIGHT INTO MONDAY MORNING. WILL MENTION STORM
IN OUR HAZARDOUS WEATHER OUTLOOK. THE PRECIPITATION SHOULD TAPER OFF
BY MONDAY EVENING WITH IT CHANGING BACK TO SNOW POSSIBLY BEFORE
ENDING AS COLD AIR IS USHERING IN. CONDITIONS WILL BECOME FAVORABLE
FOR LAKE EFFECT SNOWS IN THE WAKE OF THE SYSTEM.
COLDER AIR WILL SURGE IN BY 12Z/TUESDAY 850 MB TEMPERATURES ARE
EXPECTED TO DROP TO AROUND -25C...WITH SURFACE TEMPERATURES
BOTTOMING OUT INTO THE SINGLE DIGITS BY SUNRISE TUESDAY. DAYTIME
HIGHS TUESDAY AND WEDNESDAY WILL BE SIMILAR TO WHAT OUR NORMAL LOWS
SHOULD BE. WINDS WILL BE BRISK TUESDAY ONLY MAKING IT COLDER. COULD
HAVE ISSUES WITH WIND CHILLS AGAIN TUESDAY NIGHT INTO WEDNESDAY
MORNING.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
SNOW WILL CONTINUE THROUGH THE TAF PERIOD...12Z/FRIDAY. THE SNOW
WILL COME DOWN HEAVIEST THIS EVENING AS AREA OF LOW PRESSURE MOVES
OFF THE MID ATLANTIC COAST AND STRENGTHENS TONIGHT. IFR CONDITIONS
WILL LOWER TO LIFR FOR THE EVENING WITH THE HEAVIER SNOW. AN
IMPROVEMENT TO MVFR IS EXPECTED TO LATE IN THE PERIOD AS THE SNOW
LIGHTENS UP.
NORTH TO NORTHEAST WINDS AROUND 10 KNOTS WILL SHIFT MORE TO THE
NORTH AS THE DAY PROGRESSES AND INCREASE IN SPEED AS LOW MOVES OFF
THE MID ATLANTIC COAST AND STRENGTHENS. GUSTS TO AROUND 20 KNOTS ARE
EXPECTED.
OUTLOOK...
FRI NIGHT-SAT NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUN: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN...SLEET. SUN
NIGHT-MON: HIGH OPERATIONAL IMPACT. LIKELY RA...SN...FZRA...SLEET.
MON NIGHT-TUE: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO WIDESPREAD HYDROLOGIC PROBLEMS ARE EXPECTED OVER THE NEXT FIVE
DAYS.
A STORM SYSTEM WILL BRING SNOW TO THE REGION TODAY THROUGH
TOMORROW MORNING. VERY COLD TEMPERATURES ARE EXPECTED LATE THIS
WEEK...WHICH WILL CONTINUE TO ALLOW RIVER AND LAKE ICE TO FORM AND
THICKEN.
ANOTHER STORM SYSTEM WILL BRING PRECIPITATION TO THE REGION LATE
SUNDAY INTO MONDAY. WITH WARMER AIR EXPECTED ALOFT...PRECIPITATION
WITH THIS SYSTEM WILL BEGIN AS SNOW OR A WINTRY MIX...AND PERHAPS CHANGING
TO RAIN IN SOME AREAS. PRECIPITATION AMOUNTS ARE STILL UNCERTAIN
WITH THIS SYSTEM.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR CTZ001-013.
NY...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR NYZ038>041-043-
047>054-058>061-063>066-082>084.
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR NYZ032-033-
042.
WIND CHILL WARNING FROM 7 PM THIS EVENING TO 11 AM EST FRIDAY
FOR NYZ032-033-042.
MA...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR MAZ001-025.
VT...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...KL/FRUGIS
SHORT TERM...FRUGIS
LONG TERM...IAA
AVIATION...IAA
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
925 PM EST FRI JAN 3 2014
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION TONIGHT...THEN GRADUALLY
SHIFT OFF THE MID-ATLANTIC COAST AND INTO THE ATLANTIC OVER THE
WEEKEND...AS A COASTAL TROUGH DEVELOPS JUST OFFSHORE. THE COASTAL
TROUGH WILL LIFT NORTHWARD AS A WARM FRONT ON SUNDAY...FOLLOWED BY
THE PASSAGE OF A POTENT COLD FRONT EARLY MONDAY. ARCTIC HIGH
PRESSURE WILL THEN BUILD IN WAKE OF THE FRONT AND LINGER THROUGH
THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
THE CENTER OF ARCTIC HIGH PRESSURE WILL DROP SOUTHEAST TONIGHT AND
BE CENTERED NEAR THE VIRGINIA TIDEWATER BY SUNRISE SATURDAY. LOW
DEWPOINTS...CLEAR SKIES AND SOME RESIDUAL COLD AIR ADVECTION WILL
ALLOW TEMPERATURES TO STEADILY DROP TONIGHT...ALTHOUGH RADIATIONAL
CONDITIONS ARE NOT IDEAL. THERE IS MUCH UNCERTAINTY IN THE
TEMPERATURE FORECAST TONIGHT...ESPECIALLY ALONG THE COAST AND FAR
SOUTHERN ZONES WHERE MOST OF THE NUMERICAL MODELS SHOW COLD CELL
STRATOCUMULUS POTENTIALLY MOVING ONSHORE PRIOR TO DAYBREAK.
DESPITE THE STABILIZING EFFECTS OF THE COLD SHELF WATERS...MID-
EVENING SATELLITE TRENDS...SHORT TERM MODEL SOUNDINGS AND MODEL
SIMULATED CLOUD PRODUCTS CONTINUE TO SUGGEST THE WESTERN FLANKS
OF THE CLOSED WELL STRATOCUMULUS OFFSHORE WILL PUSH ONSHORE ALONG
THE GEORGIA AND POSSIBLY THE FAR SOUTHERN SOUTH CAROLINA COAST
OVER THE NEXT SEVERAL HOURS. TURNS OUT...THE LATEST RAP 285K
ISENTROPIC PROGNOSTICATIONS ARE DOING A FINE JOB WITH THE
EVOLUTION OF THE STRATOCUMULUS THIS EVENING...WHICH IS A THETA
SURFACE THAT IS LOWER THAN WHAT IS TYPICALLY USED IN THE COASTAL
SOUTHEAST STATES--MOST LIKELY DUE TO THE ARCTIC NATURE OF THE
AIRMASS THAT IS IN PLACE. THE INCREASED CLOUD COVER WILL OBVIOUSLY
HAVE AN IMPACT ON OVERNIGHT TEMPERATURES...MAINLY ALONG THE COAST
AND THE FAR SOUTHERN ZONES...WHERE CLOUDS ARE EXPECTED TO
PENETRATE THE FARTHEST INLAND. COASTAL OBSERVATIONS SITES ARE
ALREADY NEAR FORECASTED LOWS...SO WILL SHOW TEMPERATURES RISING
THERE OVERNIGHT AS CLOUDS THICKEN AND CEILINGS BECOME ESTABLISHED.
MANY COASTAL LOCATIONS SHOULD BE INTO THE UPPER 30S TO LOWER 40S
BY SUNRISE WHILE FARTHER INLAND...A CHILLY NIGHT IS STILL EXPECTED
WHERE RADIATIONAL EFFECTS WILL BE THE GREATEST...THOUGH NOT IDEAL.
LOWS WILL RANGE FROM THE LWR-MID 20S WELL INLAND TO THE MID 30S AT
THE BEACHES.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY NIGHT/...
SATURDAY AND SATURDAY NIGHT...THE MID/UPPER LEVEL FLOW WILL BECOME
MORE CYCLONIC IN RESPONSE TO FALLING HEIGHTS ACROSS THE PLAINS.
MEANWHILE AT THE SURFACE...HIGH PRESSURE ALONG THE MID-ATLANTIC
COAST WILL GRADUALLY SHIFT INTO THE ATLANTIC...ALLOWING A COASTAL
TROUGH TO FORM AND STRENGTHEN JUST OFFSHORE THROUGH SATURDAY NIGHT.
MARINE STRATOCUMULUS AND ISOLATED SHOWERS WITHIN AN AREA OF LOW
LEVEL CONVERGENCE IN THE VICINITY OF THE COASTAL TROUGH SHOULD HAVE
TROUBLE CROSSING THE COOL NEAR SHORE SHELF WATERS INITIALLY.
HOWEVER...AS THE DAY PROGRESSES THE FORECAST WILL SHOW A SLIGHT
CHANCE OF SHOWERS ALONG THE IMMEDIATE SOUTHEAST GEORGIA COAST...WITH
A SLIGHT CHANCE OF SHOWERS DEVELOPING ACROSS THE REMAINDER OF INLAND
AREAS SATURDAY NIGHT AS ISENTROPIC ASCENT STRENGTHENS AND LOW LEVEL
MOISTURE INCREASES. TEMPERATURES SHOULD ONLY WARM TO HIGHS IN THE
LOWER TO MID 50S SATURDAY WITH A COOL NORTHERLY FLOW
PERSISTING...BUT TEMPERATURES SATURDAY NIGHT WILL NOT FALL
SIGNIFICANTLY WITH INCREASING CLOUD COVER AS LOWS ARE FORECAST TO BE
AROUND 40 INLAND TO THE MID AND UPPER 40S CLOSER TO THE COAST.
SUNDAY...SURFACE HIGH PRESSURE WILL SHIFT FARTHER INTO THE
ATLANTIC...ALLOWING THE COASTAL TROUGH TO STRENGTHEN AND LIKELY MOVE
INLAND ALONG THE IMMEDIATE COAST IN THE MORNING...ESPECIALLY IN
SOUTHEAST SOUTH CAROLINA. MODELS THEN SHOW A WEAK WAVE OF LOW
PRESSURE TRACKING NORTHWARD ALONG THE TROUGH...ESSENTIALLY LIFTING
IT NORTHWARD AS A WARM FRONT LATER IN THE DAY. A WARM SOUTHERLY FLOW
WILL THEN DEVELOP AHEAD OF A STRONG COLD FRONT APPROACHING FROM THE
WEST. GIVEN THE PROXIMITY OF THE COASTAL TROUGH...DEEPENING MOISTURE
PROFILES AND WEAK ISENTROPIC ASCENT...WILL FORECAST A CHANCE OF
SHOWERS ACROSS MUCH OF THE AREA. HIGHS SHOULD BE AROUND 60 INLAND
WITH LOWER TO MID 60S CLOSER TO THE COAST.
SUNDAY NIGHT...A HIGHLY AMPLIFIED UPPER LEVEL TROUGH WILL DIG
SOUTHWARD FROM THE GREAT LAKES REGION...PUSHING A POTENT COLD FRONT
THROUGH THE AREA LATE SUNDAY NIGHT. EXPECT A SOLID CHANCE OF SHOWERS
IN ASSOCIATION WITH THE COLD FRONT...BUT RAINFALL AMOUNTS DO NOT
APPEAR TO BE ALL THAT SIGNIFICANT AS THE FRONT IS RATHER
PROGRESSIVE. IT IS VERY POSSIBLE THAT TEMPERATURES WILL RISE THROUGH
THE EVENING WITH ONGOING WARM AIR ADVECTION AND A STRENGTHENING
SOUTHWEST FLOW...BEFORE DROPPING OFF SIGNIFICANTLY IN WAKE OF THE
FRONT TOWARD DAYBREAK.
MONDAY AND MONDAY NIGHT...DEEP/HIGHLY AMPLIFIED UPPER LEVEL
TROUGHING WILL SPREAD OVER THE EASTERN UNITED STATES. THE COLD FRONT
WILL RAPIDLY SHIFT OFFSHORE EARLY MONDAY MORNING BRINGING AN END TO
ANY OF THE SHOWERS. VERY STRONG COLD AIR ADVECTION WILL THEN
COMMENCE AS ARCTIC HIGH PRESSURE SHIFTS EAST FROM THE PLAINS INTO
THE LOWER MISSISSIPPI VALLEY THROUGH MONDAY NIGHT. WINDY CONDITIONS
WILL DEVELOP ON MONDAY AND PERSIST THROUGH MONDAY NIGHT WITH WIND
GUSTS OF 30-40 MPH OR MORE POSSIBLE AT TIMES. THIS COULD WARRANT THE
NEED FOR WIND ADVISORIES. TEMPERATURES ON MONDAY ARE EXPECTED TO
FALL THROUGH MOST OF THE DAY DUE TO THE COLD AIR ADVECTION...WITH
TEMPERATURES REACHING THE MID 30S WELL INLAND AND MID 40S CLOSER TO
THE COAST BY THE END OF THE DAY. WIND CHILL VALUES WILL BE
SIGNIFICANTLY COLDER. VERY COLD CONDITIONS ARE EXPECTED MONDAY
NIGHT...WITH LOWS OF 15-20 INLAND AND IN THE LOWER TO MID 20S EVEN
NEAR THE IMMEDIATE COAST. FACTORING IN THE WIND...IT IS VERY
POSSIBLE MINIMUM WIND CHILL VALUES COULD BE IN THE SINGLE DIGITS IN
MOST AREAS. WIND CHILL ADVISORIES MAY BE NEEDED FOR SOME INLAND
LOCATIONS IF WINDS REMAIN STRONG IN CONJUNCTION WITH THE COLDEST
TEMPERATURES.
LAKE WINDS...WINDS OVER LAKE MOULTRIE ARE EXPECTED TO INCREASE
SIGNIFICANTLY FOLLOWING THE PASSAGE OF A STRONG COLD FRONT LATE
SUNDAY NIGHT...WITH DANGEROUS CONDITIONS POSSIBLE ON THE LAKE
THROUGH MONDAY NIGHT AS A VERY COLD AIR MASS PASSES OVER THE
RELATIVELY WARMER WATERS OF THE LAKE. LAKE WIND ADVISORIES MAY BE
NEEDED.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY THROUGH WEDNESDAY...THE MAIN ISSUE OVER THE LONG TERM
WILL BE VERY COLD TEMPERATURES ASSOCIATED WITH A LARGE AREA OF HIGH
PRESSURE EXPANDING OVER THE REGION FROM THE WEST. CONDITIONS LOOK TO
BE COLDEST ON TUESDAY AS WEST/NORTHWEST FLOW PERSISTS ALONG THE
EASTERN EDGE OF THE HIGH CENTERED TO OUR WEST/NORTHWEST. TEMPS WILL
STRUGGLE TO REACH THE MID AND UPPER 30S FOR AFTERNOON HIGHS ON
TUESDAY AND SHOULD BOTTOM OUT INTO THE TEENS INLAND AND LOW/MID 20S
ALONG THE COAST TUESDAY NIGHT. THE SFC HIGH WILL THEN SHIFT TOWARDS
NORTHEASTERN UNITED STATES ON WEDNESDAY....RESULTING IN A GRADUAL
MODIFICATION OF TEMPS OVER THE AREA AS SFC WINDS SHIFT FROM A
NORTHWEST FLOW TO EAST/NORTHEAST FLOW. IN GENERAL...HIGH TEMPS
SHOULD RANGE IN THE MID 40S INLAND TO UPPER 40S/LOWER 50S ALONG THE
IMMEDIATE COAST.
THURSDAY AND FRIDAY...A COASTAL TROUGH SHOULD DEVELOP ALONG THE
SOUTHERN PERIPHERY OF HIGH PRESSURE SLIDING OFF THE MID ATLANTIC AND
NORTHEAST COAST LATE WEEK. THIS FEATURE ALONG WITH INCREASING
ISENTROPIC ASCENT SHOULD LEAD TO A FEW SHOWERS OVER THE ENTIRE AREA
BY THURSDAY AFTERNOON...WITH HIGHEST CHANCES ALONG THE COAST. A
WEAKER COLD FRONT SHOULD THEN SHIFT THROUGH THE AREA THURSDAY NIGHT
INTO FRIDAY WITH COLD HIGH PRESSURE BUILDING OVER THE REGION INTO
EARLY WEEKEND. OVERALL HIGH TEMPS SHOULD RANGE IN THE UPPER 50S TO
LOWER 60S...WARMEST ALONG THE GEORGIA COAST.
&&
.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
THE MAIN FORECAST CONCERN IS THE POTENTIAL INTRUSION OF LOW
CLOUDS FROM THE ATLANTIC WATERS AFTER MIDNIGHT...AS A COASTAL
TROUGH DEVELOPS ON THE PERIPHERY OF THE SURFACE HIGH TO THE NORTH.
PREFER TO REMAIN RATHER CONSERVATIVE AT THIS POINT...AND DELAY
MENTION OF ANY CLOUDS OTHER THAN CIRRUS UNTIL AFTER DAYBREAK
SATURDAY. WILL THEN INTRODUCE MARGINAL MVFR CIGS FROM 13Z ON AT
KSAV AND 17Z ON AT KCHS. THERE IS A POTENTIAL FOR CIGS CLOSER TO
IFR THRESHOLDS...BUT CONFIDENCE IS NOT HIGH ENOUGH TO INCLUDE A
MENTION JUST YET.
EXTENDED AVIATION OUTLOOK...POTENTIAL FOR MVFR CEILINGS/
VISIBILITIES AS A COASTAL TROUGH STRENGTHENS JUST OFFSHORE
SATURDAY INTO SUNDAY...THEN AS A COLD FRONT MOVES THROUGH SUNDAY
NIGHT. VFR CONDITIONS WILL RETURN ON MONDAY...BUT EXPECT WINDY
CONDITIONS AT THE TERMINALS MONDAY AND MONDAY NIGHT.
&&
.MARINE...
TONIGHT...A SMALL CRAFT ADVISORY WILL REMAIN IN FORCE FOR THE
GEORGIA OFFSHORE LEG OVERNIGHT. A LINGERING TIGHT PRESSURE
GRADIENT WILL SUPPORT 15-20 KT WINDS TONIGHT FOR MOST AREAS WITH
SLIGHTLY LOWER WINDS IN THE CHARLESTON HARBOR. SEAS WILL REMAIN
ELEVATED...HOLDING 3-5 FT NEARSHORE WATERS AND 5-7 FT SUBSIDING TO
4-6 FT OFFSHORE WATERS. THERE ARE SOME INDICATIONS THAT MESOSCALE
PINCHING OF THE PRESSURE GRADIENT MAY OCCUR ACROSS THE SOUTH
CAROLINA WATERS AS A COASTAL TROUGH DEVELOPS OFFSHORE. SHOULD THIS
OCCUR...THEN THIS MAY BE ENOUGH TO TIP CONDITIONS BACK INTO
ADVISORY CRITERIA. THIS WILL BE WATCHED CAREFULLY OVERNIGHT.
SATURDAY THROUGH SUNDAY...A COASTAL TROUGH WILL DEVELOP ON SATURDAY
ALONG THE SOUTHEAST COAST AND STRENGTHEN INTO EARLY SUNDAY...BEFORE
LIFTING NORTHWARD LATER SUNDAY. THE GRADIENT BETWEEN THE COASTAL
TROUGH AND INLAND HIGH PRESSURE COULD SUPPORT WINDS OF 15-20 KT AT
TIMES SATURDAY INTO SATURDAY NIGHT...BEFORE DIMINISHING ON SUNDAY.
HOWEVER...SMALL CRAFT ADVISORY CONDITIONS ARE NOT EXPECTED DURING
THIS TIME.
SUNDAY NIGHT THROUGH MONDAY NIGHT...CONDITIONS WILL DETERIORATE
RAPIDLY LATE SUNDAY NIGHT AND EARLY MONDAY AS A STRONG COLD FRONT
SHIFTS OFFSHORE. VERY STRONG COLD AIR ADVECTION WITH BUILDING ARCTIC
HIGH PRESSURE FROM THE WEST WILL LIKELY PRODUCE GALE FORCE WINDS
ACROSS MOST OF THE WATERS MONDAY INTO MONDAY NIGHT AND GALE
WATCHES/WARNINGS MAY EVENTUALLY BE NEEDED.
TUESDAY THROUGH WEDNESDAY...EXPECT CONDITIONS TO STEADILY IMPROVE
WITH WINDS/SEAS LIKELY DROPPING BELOW SMALL CRAFT ADVISORY LEVELS
OVER ALL WATERS BY TUESDAY AFTERNOON.
&&
.TIDES/COASTAL FLOODING...
BELOW NORMAL TIDES WILL OCCUR ONCE AGAIN EARLY SATURDAY
MORNING...ALTHOUGH DEPARTURES WILL NOT BE NEARLY AS GREAT AS THE
PAST FEW CYCLES. EXPECT TIDES TO DROP TO ABOUT -1.0 FT MLLW AT
BOTH CHARLESTON HARBOR AND FORT PULASKI.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EST SATURDAY FOR AMZ374.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1200 PM CST THU JAN 2 2014
.MESOSCALE DISCUSSION...
1159 AM CST
THE LAKE EFFECT SNOW SHOWERS ACROSS NORTHEASTERN ILLINOIS CONTINUE
TO REMAIN CELLULAR AND IN MULTI BAND CLUSTERS. THESE SHOWERS ARE
PRODUCING PERIODS OF LOCALIZED HEAVY SNOW...WITH VIS DROPPING UNDER
A HALF MILE. HOWEVER...OUTSIDE OF THESE SHOWERS ONLY VERY LIGHT SNOW
IS OCCURRING ACROSS PORTIONS OF THE WARNED AREA. THIS APPEARS TO BE
SHORT LIVED.
ATTENTION FOR THIS AFTERNOONS ACTIVITY IS FOCUSED ON A WELL
DEVELOPED BAND OF HEAVY LAKE EFFECT SNOW...WHICH HAS DEVELOPED ALONG
A WELL DEFINED BOUNDARY LAYER CONVERGENCE ZONE ACROSS WESTERN LAKE
MICHIGAN...JUST OFF THE MKE SHORES. THIS BAND OF SNOW WILL SHIFT
SOUTHWARD ACROSS PORTIONS OF THE WARNED AREA OVER THE HOUR OR TWO.
IT APPEARS THAT THIS WILL SET UP ABOUT A 3 TO 5 HOUR PERIOD OF HEAVY
SNOW ACROSS EASTERN LAKE...AND COOK COUNTIES IN ILLINOIS THROUGH
THIS AFTERNOON...BEFORE THE WINDS BACK NORTHWESTERLY AND DRIVE THE
BAND INTO NORTHWESTERN INDIANA. DURING THIS TIME IT STILL APPEARS
THAT SNOW RATES OF 1 TO 2 INCHES PER HOUR COULD LEAD TO UP TO 4 TO 8
INCHES OF ADDITIONAL ACCUMULATIONS ACROSS ISOLATED PORTIONS OF THE
WARNED AREA. THIS PLUMB OF SNOW ALSO APPEARS THAT IT WILL PRODUCE
DECENT ACCUMULATIONS FAIRLY FAR INLAND ACROSS EASTERN SECTIONS OF
WILL...KANKEE AND POSSIBLY INTO PORTIONS OF IROQUO COUNTY AS WELL
DUE TO EHANCED BOUNDARY LAYER MOISTURE CONVERGENCE EXTENDING
SOUTHWARD WITHIN THE INVERTED SYNOPTIC SCALE TROUGH OF LOW
PRESSURE.
NORTHWESTERN INDIANA WILL SEE PERIODS OF LAKE EFFECT SNOW LATER THIS
AFTERNOON AND THIS EVENING. IT APPERS SNOWFALL AMOUNTS HERE WILL
ALSO EXCEED 6 INCHES ACROSS PORTIONS OF LAKE AND PORTER COUNTIES
THROUGH THIS EVENING BEFORE IT WINDS DOWN OVERNIGHT.
KJB
&&
.DISCUSSION...
854 AM CST
WE ARE MAKING SOME QUICK UPDATES TO THE HEADLINES THIS MORNING BASED
ON CURRENT TRENDS. WE WILL BE UPGRADING DUPAGE AND WILL COUNTIES IN
ILLINOIS TO LAKE EFFECT SNOW WARNINGS AND ADDING KANKAKEE COUNTY
INTO A LAKE EFFECT SNOW ADVISORY. WE ARE ALSO ADDING JASPER AND
NEWTON COUNTIES IN INDIANA TO THE ADVISORY AND UPGRADING PORTER TO A
WARNING.
AREA OBSERVATIONS AND RADAR IMAGERY INDICATES THAT THE MAIN
CONVERGENCE AXIS IS BEGINNING TO ORIENT ITSELF RIGHT ACROSS
NORTHEASTERN ILLINOIS. CURRENT INDICATIONS BASED ON OBSERVATIONS
INDICATES THAT THE CURRENT SHOWERY NATURE TO THE SNOW...WILL
ORGANIZE INTO A SINGLE BAND OF HEAVY LAKE EFFECT SNOW BY EARLY
AFTERNOON...AND THIS LOOKS TO SET UP RIGHT ACROSS PORTIONS OF LAKE
ILLINOIS...SOUTHWARD THROUGH COOK...FAR EASTERN DUPAGE...THROUGH
WILL AND KANKAKEE COUNTIES IN ILLINOIS THROUGH AT LEAST MID TO LATE
AFTERNOON. THIS BAND WILL THEN SHIFT EASTWARD ACROSS NORTHWESTERN
INDIANA THROUGH THE EVENING. SNOWFALL RATES HAVE ALREADY BEEN AROUND
OR JUST ABOVE AN INCH PER HOUR IN THE HEAVIER SNOW SHOWERS...AND
THESE RATES COULD EVEN INCREASE SOME AS THE BAND BECOME BETTER
ORGANIZED BY EARLY THIS AFTERNOON. SOME SNOW RATES COULD EXCEED 2"
PER HOUR. AS SUCH...SOME AREAS ACROSS THE WARNING AREA COULD GET IN
EXCESS OF 10 INCHES OF SNOW BEFORE THE SNOW TAPPERS LATE THIS
AFTERNOON.
THE NATURE OF THE SYNOPTIC SCALE INVERTED SURFACE TROUGH WILL ALLOW
THE LAKE EFFECT SNOW SHOWERS TO REACH WELL INLAND ACROSS PORTIONS OF
EAST CENTRAL ILLINOIS. THIS IS THE REASON FOR THE EXPANSION OF THE
ADVISORY INTO KANKAKEE IN ILLINOIS AND JASPER AND NEWTON COUNTIES IN
INDIANA.
IN ADDITION TO THE HEAVY SNOW...NORTHEAST WINDS OFF OF LAKE
MICHIGAN COULD GUST UP AROUND 30 KT...AND THIS WILL PRODUCE
BLOWING AND DRIFTING SNOW...ESPECIALLY NEAR THE LAKE. ALL AND
ALL...BLIZZARD LIKE CONDITIONS COULD DEVELOP UNDER THE HEAVIER
SNOW SHOWERS...WITH NEAR ZERO VIS POSSIBLE AT TIMES THIS
AFTERNOON.
KJB
//PREV DISCUSSION...
352 AM CST
SNOW AND COLD ONCE AGAIN ARE THE REPETITIVE HEADLINES TO THIS
FORECAST...AND IN FACT ARE THE HEADLINES THAT WE HAVE IN EFFECT.
THERE ARE LAKE EFFECT SNOW HEADLINES FOR TODAY ACROSS NORTHEAST IL
AND INTO NORTHWEST INDIANA TONIGHT...WITH SOME ADJUSTMENTS DONE FOR
TIMING AS WELL AS ADDING COUNTIES FOR AN ADVISORY. A WIND CHILL
ADVISORY HAS BEEN ISSUED FOR TONIGHT INTO FRIDAY MORNING FOR MUCH OF
NORTH CENTRAL AND PARTS OF NORTHEAST IL.
THE MASSIVE UPPER LEVEL TROUGH AND ITS EXPANSIVE COLD DEEP AIR
/500MB TEMPS NEARING -40C IN THE GREAT LAKES REGION/ REMAIN
ESTABLISHED OVER THE AREA. THIS IS EVEN SEEN ON THE HEMISPHERIC
WATER VAPOR IMAGERY THIS MORNING WITH A VERY EVIDENT DEEP ROSBY WAVE
CENTERED FROM HUDSON BAY TO GREENLAND AND EXTENDING ACROSS
CENTRAL/EASTERN NORTH AMERICA. PRONOUNCED JET AND UPPER SHORT WAVE
IS ROUNDING THE BASE OF THIS TROUGH ACROSS THE LOWER OHIO VALLEY
EARLY THIS MORNING. THIS WAS THE MAIN CAUSE OF OUR SNOW YESTERDAY
AND THAT HAS ALL BUT SHIFTED EAST OUT OF THE AREA EARLY THIS
MORNING...SO WILL BE ABLE TO LET THE WINTER WEATHER ADVISORY END AT
6 AM.
LOW PRESSURE OF 1013MB IS DEEPENING ACROSS TENNESSEE EARLY THIS
MORNING AND THAT WILL FURTHER DO SUCH INTO THE MID-ATLANTIC BY EARLY
EVE. WITH THE STRONG ARCTIC HIGH BUILDING INTO THE PLAINS...THIS
OVERALL PRESSURE EVOLUTION WILL FAVOR GRADUALLY VEERING WINDS ACROSS
THE LAKE. THIS SLOW VEERING WILL LIKELY HELP TO KEEP A MESOSCALE LOW
PRESSURE TROUGH/CONVERGENCE AXIS INTACT ACROSS THE FAR WESTERN PART
OF THE LAKE THROUGH THE MORNING. THIS AXIS EARLY THIS MORNING IS
ABOUT 35 MILES INLAND ACROSS NORTHEAST IL...BUT WILL SHIFT BACK OUT
TOWARD THE LAKE SHORE...LIKELY TOWARD MIDDAY AND BE THE FOCUS FOR
THE HEAVIEST LAKE EFFECT SNOW AND A LIKELY COUPLE/FEW HOUR PERIOD OF
VERY HEAVY RATES GIVEN THE VERY FAVORABLE PARAMETERS. THESE INCLUDE
STRONG LAKE-INDUCED INSTABILITY IN EXCESS OF 500 J/KG...THIS
INSTABILITY MAINLY COLLOCATED WITH SUPERSATURATION WITH RESPECT TO
ICE AND WITHIN THE DENDRITIC GROWTH AREA...AND CLOUD DEPTHS OF
9-10KFT. ALL THIS HAS BEEN CONSISTENTLY SHOWN BY THE NAM AND LOCAL
ARW.
PRIOR TO THIS AXIS...GENERAL ONSHORE FLOW INTO NORTHEAST IL HAS
ENOUGH INSTABILITY WITH IT TO BE DEVELOPING WIDESPREAD LAKE EFFECT
SNOW SHOWERS THIS MORNING...AND THESE ACTUALLY EXTEND AS FAR WEST IN
ILLINOIS AS ROCHELLE AND MENDOTA! A LONGER FETCH OF INSTABILITY IS
GRADUALLY WORKING INTO LAKE COUNTY IL FROM THE NORTH AND BASED ON
OBSERVATIONS OF LOWERING VISIBILITIES TO AT OR UNDER A
MILE...ACCUMULATIONS OF AROUND ONE HALF INCH PER HOUR WILL SLOWLY
SPREAD SOUTH. SO GIVEN THAT SNOW SHOWERS ARE ALREADY ONGOING WITH
PARAMETERS ONLY BETTERING...SEE NO REASON SNOW SHOWERS WILL NOT STOP
FOR NORTHEAST IL UNTIL THE FLOW TURNS OFFSHORE. THE HEAVIEST SNOW
AGAIN WILL BE CONFINED TO NEAR THAT CONVERGENT AXIS AND USING OUR
LOCAL 8KM ARW...THAT LOOKS TO LINE ITSELF INTO DOWNTOWN CHICAGO
DURING THE EARLY TO MID AFTERNOON...BEFORE SHIFTING EASTWARD INTO
NORTHWEST IN. THIS TIMING OF THE PROBABLE HEAVIEST RATES AND
DURATION IN WHICH THEY LAST...WILL LIKELY BE DEPENDENT ON IF A
MESOSCALE CIRCULATION CAN REMAIN INTACT OVER THE FAR SOUTHERN PART OF
THE LAKE TOO...BASICALLY SLOWLY THAT EASTWARD PROGRESSION. THE
LONGER THAT DOES SUCH...THE MORE PROBABLE THAT SOME CORRIDOR OF THE
LAKE EFFECT WARNING WILL REALIZE 6 OR MORE...POSSIBLY EVEN 8-10
INCHES OF SNOW. THE CONVERGENCE BEGINS TO WEAKEN LATE THIS EVENING
INTO NORTHWEST INDIANA AS IT CONTINUES TO PIVOT EAST...SO THAT
RESULTS IN SNOW ENDING FROM WEST TO EAST ACROSS ADJACENT COUNTIES TO
SOUTHERN LAKE MICHIGAN.
MODEL GUIDANCE REMAINS IN STRONG AGREEMENT WITH ANTICYCLONIC FLOW IN
THE LOW-LEVELS AND SUPPRESSION ALOFT DISSIPATING CLOUDS QUICKLY FROM
WEST TO EAST ACROSS NORTHERN IL LATE THIS AFTERNOON AND THIS EVE.
RADIATIONAL COOLING...HIGHLY ANOMALOUS COLD ATMOSPHERIC AIR...SLOWLY
DECREASING FLOW...AND A FRESH SNOWPACK ALL LOOK TO STILL COLLOCATE
FOR A VERY CHILLY NIGHT. HAVE MINS STILL IN THE -11 TO -18 ARENA
ACROSS ALL OF NORTH CENTRAL IL. HAVE HOISTED A WIND CHILL ADVISORY
AS WINDS WILL MAINTAIN ENOUGH FLOW TO MAKE IT DANGEROUS FOR ANY
PROLONGED EXPOSE SKIN.
FOR THIS WEEKEND WE CONTINUE TO WATCH A SYSTEM OF INTEREST. THE NEXT
IN A SERIES OF COLD FRONTS IS EXPECTED TO PASS SATURDAY AFTERNOON
WITH THE CHANCE FOR LIGHT SNOW. THE SLOWER EC HAS BEEN FOLLOWED
WHICH KEEPS THIS CHANCE OF SNOW AREAWIDE MAINLY DURING THE LATE
AFTERNOON AND NIGHT. AS THE NEXT UPPER TROUGH DEEPENS TO OUR
WEST...MUCH LIKE YESTERDAY...THAT WILL ENHANCE THE BAROCLINIC ZONE
OVER THE REGION POTENTIALLY PROVIDING FOR A FOCUS FOR SNOW LATER
SATURDAY NIGHT INTO SUNDAY. DO HAVE SOME LIKELY POPS IN THE
SOUTHEAST FORECAST AREA...BUT KNOWING THAT SHIFTS ARE INEVITABLE
WITH THIS HAVE NOT TRIED TO GET TOO FANCY. AT THIS TIME IT APPEARS
CHICAGO MAY BE GRAZED WITH THIS.
MTF
MONDAY THROUGH WEDNESDAY...
MAJOR ARCTIC BLAST ARRIVES EARLY MONDAY MORNING...WITH THE LATEST
GUIDANCE SHOWING NO SIGNS OF BACKING OFF ON THE DANGEROUSLY COLD
LOWS AND HIGH TEMPS FOR THE THE MON/TUE TIME FRAME.
ENSEMBLES FOR OVER A WEEK NOW HAVE INDICATED AN ARCTIC BLAST
ARRIVING FOR THE START OF NEXT WEEK...AND THIS CONTINUES TO BE THE
THEME. THE 500MB TROUGH AXIS ARRIVES OVER THE GREAT LAKES REGION
MON...AND WITH WEAK RIDGING OVER THE WESTERN ATLANTIC OCEAN
STRETCHING NORTH THROUGH THE CANADIAN MARITIME. THIS RIDGING WILL
LIKELY SLOW THE FORWARD PROGRESSION TO THE TROUGH AXIS...ALLOWING IT
TO LINGER LONGER OVER THE GREAT LAKES INTO TUE. THEN HEADING INTO
WED THE RIDGING OVER THE WESTERN ATLANTIC BEGINS TO PUSH
EAST...WHICH WILL ALLOW FOR A RELATIVELY MORE FLUID ATMOSPHERE AND
THE TROUGH AXIS WILL DRIFT EAST/NORTHEAST TOWARDS NEW ENGLAND.
AS PREVIOUSLY NOTED ABOUT THE COLD AIR...ENSEMBLES FOR NUMEROUS DAYS
HAVE BEEN PAINTING A HIGH CONFIDENCE THAT AT 850MB TEMPS BY EARLY
MON WILL BE ARND -24 TO -28 DEG C...WITH A POCKET OF -30 DEG C JUST
NORTH OF THE FORECAST AREA INTO CENTRAL/NORTHERN WISC. WITH THE SLOW
FORWARD PROPAGATION TO THE MID-LVL TROUGH...THIS WILL LIKELY KEEP
THE POTENT THERMAL TROUGH OVERHEAD INTO TUE. CLOSER TO THE SFC
RIDGING IS EXPECTED TO PUSH IN BEHIND THE ARCTIC FRONTAL BOUNDARY
AND PROVIDE RELATIVELY LITTLE IN THE WAY OF PRECIP TO THE FORECAST
AREA MON/TUE. UNFORTUNATELY WITH HOW COLD TEMPS WILL BE ALOFT AND A
THICK BLANKET OF SNOW...SFC TEMPS WILL EASILY HOLD WELL BELOW ZERO
FOR HIGHS BOTH MON/TUE. AT THIS TIME HIGH TEMPS MAY STRUGGLE ON BOTH
DAYS TO REACH -5 DEG F...WITH POSSIBLY A FEW LOCATIONS IN OUR
WESTERN CWFA STRUGGLING TO REACH -10 DEG C MON AFTN.
DEPENDING ON CLOUD COVER...OVERNIGHT LOWS COULD EASILY APPROACH
RECORD LOWS AT -15 TO -20 DEG F IN THIS TIMEFRAME. THE COMBINATION
OF DANGEROUSLY COLD SFC TEMPS...AND A GRADIENT PRODUCING BREEZY
CONDITIONS...WILL SET THE STAGE FOR WIND CHILL VALUES LIKELY TO
EXCEED -30 BELOW AND POSSIBLY APPROACH -40 DEG MON NGT. THE
GRADIENT SLACKENS FOR TUE NGT...HOWEVER WIND CHILL VALUES WILL ONCE
AGAIN APPROACH -20 TO -30 DEG F.
THEN TOWARDS THE MIDDLE OF NEXT WEEK THE TROUGH AXIS PIVOTS
EAST...WITH FLOW TURNING SOUTH/SOUTHWEST AND ADVECTING MUCH WARMER
AIR INTO THE REGION. ENSEMBLES HAVE CONTINUED TO INDICATE RELATIVELY
HIGH CONFIDENCE IN THE LONGER TERM PERIODS...WITH A MID-LVL TROUGH
DIGGING INTO THE SOUTHERN PLAINS AND POSSIBLY LEADING TO YET ANOTHER
ACTIVE PERIOD OF WEATHER FOR THE MIDDLE OF NEXT WEEK.
CONFIDENCE IN TEMPS MON/TUE...HIGH.
CONFIDENCE IN WIND CHILL VALUES MON/TUE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* CIG/VSBY TRENDS THROUGH EARLY AFTERNOON WITH LAKE EFFECT SNOW.
* VARIABLE NORTH-NORTHWEST TO NORTH-NORTHEAST WINDS TRENDING
NORTH-NORTHWEST LATE THIS MORNING AT ORD...AND THIS AFTERNOON
AT MDW.
MDB/BMD
//DISCUSSION...UPDATED 14Z...
LAKE EFFECT SNOW CONTINUES TO EVOLVE WITH THE STEADIER WIDESPREAD
SNOW OF THE PAST FEW HOURS BEGINNING TO TRANSITION TO A MORE
CELLULAR AND NARROW BAND. 14Z RADAR IMAGERY SHOWS THE
BROADER/STEADIER SNOW BAND PIVOTING EASTWARD TOWARD THE GYY AREA
WITH THE NEWLY DEVELOPING NARROW/CELLULAR BAND SETTING UP FROM THE
WISCONSIN SHORELINE SOUTHWARD TO BETWEEN ORD/DPA DOWN TO JOT. AM
THINKING THAT THIS BAND MAY BECOME MORE FOCUSED IN THIS GENERAL
AREA THEN GRADUALLY PIVOT EASTWARD. THIS MORE FOCUSED BAND MAY BE
SURROUNDED BY A LARGER AREA OF LESS FOCUSED SNOW KEEPING SNOW
SHOWERS ACROSS A LARGER AREA. THE MAIN CHALLENGE WILL BE
DETERMINING HOW LONG IT WILL TAKE FOR THE MORE INTENSE SNOW TO
SHIFT EAST OF ORD/MDW...WITH DPA APPEARING TO BE JUST TO THE WEST
OF THE MAIN ACTIVITY. MAY NEED TO LOWER VSBY INTO THE 1/2SM RANGE
FOR A TIME DURING THE LATE MORNING AT ORD/MDW. GYY SHOULD START
TO SEE STEADIER SNOW WITH THE MAIN BAND ARRIVING MIDDAY/EARLY
AFTERNOON.
MDB
FROM 12Z...
A PRONOUNCED BAND OF LAKE EFFECT SNOW DEVELOPED DURING THE
PREDAWN HOURS AND WAS POSITIONED OVER THE CHICAGO METRO AREA
AROUND DAYBREAK. FLIGHT CONDITIONS WILL LIKELY REMAIN IFR THIS
MORNING DUE MAINLY TO VSBY RESTRICTIONS BUT PERIODS OF IFR CIGS
ARE ALSO POSSIBLE. DESPITE THE PERSISTENCE OF THIS BAND...HAVE
MOSTLY BEEN SEEING MVFR VSBYS WITH OCCASIONAL IFR...SO ELECTED TO
LEAN TOWARD THAT TREND IN LATEST UPDATES RATHER THAN MAINTAINING
THE LIFR FROM EARLIER FORECASTS. THIS DOES NOT MEAN LIFR IS
COMPLETELY OUT OF THE QUESTION...JUST THAT IT IS NOT EXPECTED TO
BE THE PREVAILING CONDITION FOR AN EXTENDED PERIOD OF TIME.
ACCUMULATING SNOW STILL IS EXPECTED TO WRAP UP BY MID AFTERNOON AT
THE ORD/MDW TERMINALS AS WINDS TURN NORTHWEST AND THE BAND SLIDES
SOUTH. FLURRIES ARE POSSIBLE INTO THE EVENING...THEN HIGH
PRESSURE MOVES INTO THE AREA TONIGHT.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM CONFIDENCE IN SOME IMPROVEMENT AT ORD IN NEXT COUPLE
HOURS...LOW CONFIDENCE ON VSBY TRENDS AT MDW.
* MEDIUM-HIGH CONFIDENCE IN WIND TRENDS.
MDB/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...SNOW SHOWERS ARRIVE AFTERNOON...MVFR/IFR LIKELY.
SUNDAY...CHANCE SNOW SHOWERS AND MVFR/IFR.
MONDAY AND TUESDAY...BREEZY AND VFR...SOME MVFR POSSIBLE MONDAY.
WEDNESDAY...SNOW AND IFR POSSIBLE.
LENNING
&&
.MARINE...
326 AM CST
MAIN CONCERN IS STRONG LOW PRESSURE PASSING NORTH OF THE LAKES
FRIDAY NIGHT. LATEST MODELS CONTINUE THE TREND OF INCREASING WINDS
AND GUSTS FRIDAY NIGHT...SO ELECTED TO REPLACE THE GALE WATCH WITH
A STORM WATCH. REGARDLESS OF THE EXACT TRACK AND STRENGTH OF THE
LOW...FEEL FAIRLY CONFIDENT OF SEEING AT LEAST A PERIOD OF STORM
FORCE GUSTS...BUT NOT QUITE CONFIDENT ENOUGH YET TO GO WITH THE
WARNING. THESE STORM FORCE WINDS WOULD BE PRECEEDED BY GALES
FRIDAY AFTERNOON AND FOLLOWED BY GALES SATURDAY...BUT WILL CARRY
JUST A STORM WATCH FOR THE ENTIRE PERIOD TO AVOID COMPLICATING THE
HEADLINES.
IN THE NEARSHORE...GALES LIKELY WILL DEVELOP LATE FRIDAY INTO
SATURDAY DURING THE SAME PERIOD AS THE STORM FORCE WINDS IN THE
OPEN WATERS. SMALL CRAFT ADVISORIES CURRENTLY IN EFFECT DO LOOK
LIKE THEY CAN BE DROPPED FOR A SHORT TIME EARLY ON FRIDAY BEFORE
CONDITIONS RAPIDLY INCREASE AGAIN. TO DRAW ATTENTION TO THE SHORT
BREAK BEFORE THE NEW SYSTEM APPROACHING FRIDAY...AND TO AVOID
RUNNING THE HEADLINES TOGETHER...ELECTED TO HOLD OFF ON ISSUING A
GALE WATCH AT THIS TIME BUT DID MENTION IT IN THE FORECAST TEXT.
LENNING
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...LAKE EFFECT SNOW WARNING...ILZ006 UNTIL 3 PM THURSDAY.
WIND CHILL ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ019-ILZ020-ILZ021-ILZ032...9 PM THURSDAY
TO 10 AM FRIDAY.
LAKE EFFECT SNOW WARNING...ILZ013-ILZ014-ILZ022 UNTIL 6 PM
THURSDAY.
LAKE EFFECT SNOW ADVISORY...ILZ023 UNTIL 6 PM THURSDAY.
IN...LAKE EFFECT SNOW WARNING...INZ001-INZ002 UNTIL MIDNIGHT FRIDAY.
LAKE EFFECT SNOW ADVISORY...INZ010-INZ011 UNTIL MIDNIGHT FRIDAY.
LM...STORM WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...NOON FRIDAY TO 4 PM
SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 4 AM
FRIDAY.
SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 9 AM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
National Weather Service Lincoln IL
1126 AM CST Thu Jan 2 2014
.DISCUSSION...
ISSUED 956 AM CST Thu Jan 2 2014
Have allowed the winter weather advisory to expire across eastern
Illinois. Still seeing some visibilities from 1 to 2 miles at
times, but several reports of unknown precipitation on automated
observations are likely implying areas of blowing snow.
Main concern the remainder of the day will be with lake effect
snow. Radar returns over central Illinois have been increasing the
last few hours as moisture is advected in from southern Lake
Michigan. Latest RAP model shows the broader stream of lake effect
snow in northeast Illinois becoming more focused this afternoon
and pushing southward toward Champaign and Danville as the wind
over the lake become more north-northeast. Have maintained 30-40
percent PoP`s in the far northeast CWA into the afternoon, but
will have to watch this closely as the RAP suggests another 1-2
inches may not be out of the question in those areas with this
type of fetch. Over the remainder of the forecast area,
precipitation should start taping off to flurries and end from
west to east.
Geelhart
&&
.AVIATION...
ISSUED 1125 AM CST Thu Jan 2 2014
IFR conditions continuing at KBMI/KCMI as lake effect snow showers
spread southwest. The northeast flow causing these showers will
shift more toward the north-northeast, causing the snow axis to
swing more toward the Indiana border, but these may still affect
KCMI into mid afternoon, so will keep the lower visibilities in
the upcoming TAF issuance. Ceilings expected into improve to VFR
elsewhere over the next few hours, with the back edge of the lower
clouds currently from around KIJX-KGBG per visible satellite
imagery. Gusty northwest winds should begin to subside as high
pressure builds toward the mid-Mississippi Valley. Expect the
northwest winds to swing to the south as the high moves into
southern Illinois early Friday morning.
Geelhart
&&
.PREV DISCUSSION...
ISSUED 330 AM CST Thu Jan 2 2014
SHORT TERM...Today through Sunday night
Winter will keep a tight grip over central and southeast IL during
the next week with arctic air masses visiting the region into the
middle of next week along with a couple of weather systems
bringing more snow. Will expire the winter weather advisory along
and northwest of I-55 with forecast package at 4 am and continue
the winter wx advisory until 9 am for east central and southeast IL.
Snowfall total have generally averaged 2-3 inches across central
IL with lesser amounts in our far southeast counties where mixed
precipitation occurred since it begin late Wed evening, plus a dry
slot in that area too keeping precipitation lighter. Still have
band of light snow from I-55 southeast which HRRR diminishes from
NW to SE through 15Z/9 am. Up to another inch of snow possible
east of I-55 with 1-2 inches more snow east of I-57. Gusty NNW
winds today to cause some low drifting across east-west roads.
Elongated 1013 mb low pressure from southern Indiana into NW TN
early this morning to eject quickly to the mid Atlantic coast by
sunset and produce a winter storm over the Northeast States into
Friday. Scattered flurries over even a few light snow showers
possible over eastern IL this afternoon especially over east
central IL but any additional snow accumulations should be
confined NE of our area closer to the Great Lakes region. Highs
today range from 10-15F over the IL river valley, to the low to
mid 20s in southeast IL.
Will issue a wind chill advisory along and NW of a Rushville to
Bloomington/Normal line tonight and Friday morning for wind chills
getting down to 15-20 below zero. 1037 mb arctic high pressure
over the eastern Dakotas and NW MN to settle into the mid MS
valley Friday morning and bring very cold temps back into the
region. Clouds to decrease from west to east during tonight and
winds to also diminish allowing temps to drop into the single
digits below zero over central IL with Galesburg 10 below or even
colder. High pressure drifts east into the mid Atlantic states by
Friday evening with increasing south winds and fair amount of
sunshine but still cold highs in the upper teens and lower 20s
with fresh snow cover. Breezy south winds continue Sat with milder
temps in the low to mid 30s. Also have 20-40% chance of light snow
from I-55 NW during Sat afternoon with next wx system approaching.
Strong upper level trof to dig into the Midwest by Sunday with low
pressure ejecting NE from the southern plains into the eastern
great lakes region as it deepens. Snow to develop across central
IL Sat night and continue Sunday with be heaviest in southeast IL
where several inches of snow possible. Areas NW by the IL river
valley appear to be on NW fringe of this storm system with lighter
snow amounts. Snow to diminish during Sunday night as storm system
pulls away.
LONG TERM...Monday through Wednesday night
The coldest air of the season still slated to arrive early next
work with from Sunday night through Tue night with subzero lows
returning to central and even southeast IL by Monday night with
northern areas 10-15 below zero. Wind chills Monday night into Tue
morning to get to 20-35 below zero and coldest from I-74 north.
Flurries possible over eastern IL Monday with deep upper level
trof in place. Then next weather system appears to arrive by Wed
afternoon into Thu with next chance of snow with light snow
accumulations possible then. Models trending upward with temps
later next week as upper level heights rise, but skeptical about
too fast of warmup with snow pack in place.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY from 6 PM this evening to Noon CST Friday
FOR ILZ027>031-036>038-040-041.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1016 AM CST THU JAN 2 2014
.DISCUSSION...
854 AM CST
WE ARE MAKING SOME QUICK UPDATES TO THE HEADLINES THIS MORNING BASED
ON CURRENT TRENDS. WE WILL BE UPGRADING DUPAGE AND WILL COUNTIES IN
ILLINOIS TO LAKE EFFECT SNOW WARNINGS AND ADDING KANKAKEE COUNTY
INTO A LAKE EFFECT SNOW ADVISORY. WE ARE ALSO ADDING JASPER AND
NEWTON COUNTIES IN INDIANA TO THE ADVISORY AND UPGRADING PORTER TO A
WARNING.
AREA OBSERVATIONS AND RADAR IMAGERY INDICATES THAT THE MAIN
CONVERGENCE AXIS IS BEGINNING TO ORIENT ITSELF RIGHT ACROSS
NORTHEASTERN ILLINOIS. CURRENT INDICATIONS BASED ON OBSERVATIONS
INDICATES THAT THE CURRENT SHOWERY NATURE TO THE SNOW...WILL
ORGANIZE INTO A SINGLE BAND OF HEAVY LAKE EFFECT SNOW BY EARLY
AFTERNOON...AND THIS LOOKS TO SET UP RIGHT ACROSS PORTIONS OF LAKE
ILLINOIS...SOUTHWARD THROUGH COOK...FAR EASTERN DUPAGE...THROUGH
WILL AND KANKAKEE COUNTIES IN ILLINOIS THROUGH AT LEAST MID TO LATE
AFTERNOON. THIS BAND WILL THEN SHIFT EASTWARD ACROSS NORTHWESTERN
INDIANA THROUGH THE EVENING. SNOWFALL RATES HAVE ALREADY BEEN AROUND
OR JUST ABOVE AN INCH PER HOUR IN THE HEAVIER SNOW SHOWERS...AND
THESE RATES COULD EVEN INCREASE SOME AS THE BAND BECOME BETTER
ORGANIZED BY EARLY THIS AFTERNOON. SOME SNOW RATES COULD EXCEED 2"
PER HOUR. AS SUCH...SOME AREAS ACROSS THE WARNING AREA COULD GET IN
EXCESS OF 10 INCHES OF SNOW BEFORE THE SNOW TAPPERS LATE THIS
AFTERNOON.
THE NATURE OF THE SYNOPTIC SCALE INVERTED SURFACE TROUGH WILL ALLOW
THE LAKE EFFECT SNOW SHOWERS TO REACH WELL INLAND ACROSS PORTIONS OF
EAST CENTRAL ILLINOIS. THIS IS THE REASON FOR THE EXPANSION OF THE
ADVISORY INTO KANKAKEE IN ILLINOIS AND JASPER AND NEWTON COUNTIES IN
INDIANA.
IN ADDITION TO THE HEAVY SNOW...NORTHEAST WINDS OFF OF LAKE
MICHIGAN COULD GUST UP AROUND 30 KT...AND THIS WILL PRODUCE
BLOWING AND DRIFTING SNOW...ESPECIALLY NEAR THE LAKE. ALL AND
ALL...BLIZZARD LIKE CONDITIONS COULD DEVELOP UNDER THE HEAVIER
SNOW SHOWERS...WITH NEAR ZERO VIS POSSIBLE AT TIMES THIS
AFTERNOON.
KJB
//PREV DISCUSSION...
352 AM CST
SNOW AND COLD ONCE AGAIN ARE THE REPETITIVE HEADLINES TO THIS
FORECAST...AND IN FACT ARE THE HEADLINES THAT WE HAVE IN EFFECT.
THERE ARE LAKE EFFECT SNOW HEADLINES FOR TODAY ACROSS NORTHEAST IL
AND INTO NORTHWEST INDIANA TONIGHT...WITH SOME ADJUSTMENTS DONE FOR
TIMING AS WELL AS ADDING COUNTIES FOR AN ADVISORY. A WIND CHILL
ADVISORY HAS BEEN ISSUED FOR TONIGHT INTO FRIDAY MORNING FOR MUCH OF
NORTH CENTRAL AND PARTS OF NORTHEAST IL.
THE MASSIVE UPPER LEVEL TROUGH AND ITS EXPANSIVE COLD DEEP AIR
/500MB TEMPS NEARING -40C IN THE GREAT LAKES REGION/ REMAIN
ESTABLISHED OVER THE AREA. THIS IS EVEN SEEN ON THE HEMISPHERIC
WATER VAPOR IMAGERY THIS MORNING WITH A VERY EVIDENT DEEP ROSBY WAVE
CENTERED FROM HUDSON BAY TO GREENLAND AND EXTENDING ACROSS
CENTRAL/EASTERN NORTH AMERICA. PRONOUNCED JET AND UPPER SHORT WAVE
IS ROUNDING THE BASE OF THIS TROUGH ACROSS THE LOWER OHIO VALLEY
EARLY THIS MORNING. THIS WAS THE MAIN CAUSE OF OUR SNOW YESTERDAY
AND THAT HAS ALL BUT SHIFTED EAST OUT OF THE AREA EARLY THIS
MORNING...SO WILL BE ABLE TO LET THE WINTER WEATHER ADVISORY END AT
6 AM.
LOW PRESSURE OF 1013MB IS DEEPENING ACROSS TENNESSEE EARLY THIS
MORNING AND THAT WILL FURTHER DO SUCH INTO THE MID-ATLANTIC BY EARLY
EVE. WITH THE STRONG ARCTIC HIGH BUILDING INTO THE PLAINS...THIS
OVERALL PRESSURE EVOLUTION WILL FAVOR GRADUALLY VEERING WINDS ACROSS
THE LAKE. THIS SLOW VEERING WILL LIKELY HELP TO KEEP A MESOSCALE LOW
PRESSURE TROUGH/CONVERGENCE AXIS INTACT ACROSS THE FAR WESTERN PART
OF THE LAKE THROUGH THE MORNING. THIS AXIS EARLY THIS MORNING IS
ABOUT 35 MILES INLAND ACROSS NORTHEAST IL...BUT WILL SHIFT BACK OUT
TOWARD THE LAKE SHORE...LIKELY TOWARD MIDDAY AND BE THE FOCUS FOR
THE HEAVIEST LAKE EFFECT SNOW AND A LIKELY COUPLE/FEW HOUR PERIOD OF
VERY HEAVY RATES GIVEN THE VERY FAVORABLE PARAMETERS. THESE INCLUDE
STRONG LAKE-INDUCED INSTABILITY IN EXCESS OF 500 J/KG...THIS
INSTABILITY MAINLY COLLOCATED WITH SUPERSATURATION WITH RESPECT TO
ICE AND WITHIN THE DENDRITIC GROWTH AREA...AND CLOUD DEPTHS OF
9-10KFT. ALL THIS HAS BEEN CONSISTENTLY SHOWN BY THE NAM AND LOCAL
ARW.
PRIOR TO THIS AXIS...GENERAL ONSHORE FLOW INTO NORTHEAST IL HAS
ENOUGH INSTABILITY WITH IT TO BE DEVELOPING WIDESPREAD LAKE EFFECT
SNOW SHOWERS THIS MORNING...AND THESE ACTUALLY EXTEND AS FAR WEST IN
ILLINOIS AS ROCHELLE AND MENDOTA! A LONGER FETCH OF INSTABILITY IS
GRADUALLY WORKING INTO LAKE COUNTY IL FROM THE NORTH AND BASED ON
OBSERVATIONS OF LOWERING VISIBILITIES TO AT OR UNDER A
MILE...ACCUMULATIONS OF AROUND ONE HALF INCH PER HOUR WILL SLOWLY
SPREAD SOUTH. SO GIVEN THAT SNOW SHOWERS ARE ALREADY ONGOING WITH
PARAMETERS ONLY BETTERING...SEE NO REASON SNOW SHOWERS WILL NOT STOP
FOR NORTHEAST IL UNTIL THE FLOW TURNS OFFSHORE. THE HEAVIEST SNOW
AGAIN WILL BE CONFINED TO NEAR THAT CONVERGENT AXIS AND USING OUR
LOCAL 8KM ARW...THAT LOOKS TO LINE ITSELF INTO DOWNTOWN CHICAGO
DURING THE EARLY TO MID AFTERNOON...BEFORE SHIFTING EASTWARD INTO
NORTHWEST IN. THIS TIMING OF THE PROBABLE HEAVIEST RATES AND
DURATION IN WHICH THEY LAST...WILL LIKELY BE DEPENDENT ON IF A
MESOSCALE CIRCULATION CAN REMAIN INTACT OVER THE FAR SOUTHERN PART OF
THE LAKE TOO...BASICALLY SLOWLY THAT EASTWARD PROGRESSION. THE
LONGER THAT DOES SUCH...THE MORE PROBABLE THAT SOME CORRIDOR OF THE
LAKE EFFECT WARNING WILL REALIZE 6 OR MORE...POSSIBLY EVEN 8-10
INCHES OF SNOW. THE CONVERGENCE BEGINS TO WEAKEN LATE THIS EVENING
INTO NORTHWEST INDIANA AS IT CONTINUES TO PIVOT EAST...SO THAT
RESULTS IN SNOW ENDING FROM WEST TO EAST ACROSS ADJACENT COUNTIES TO
SOUTHERN LAKE MICHIGAN.
MODEL GUIDANCE REMAINS IN STRONG AGREEMENT WITH ANTICYCLONIC FLOW IN
THE LOW-LEVELS AND SUPPRESSION ALOFT DISSIPATING CLOUDS QUICKLY FROM
WEST TO EAST ACROSS NORTHERN IL LATE THIS AFTERNOON AND THIS EVE.
RADIATIONAL COOLING...HIGHLY ANOMALOUS COLD ATMOSPHERIC AIR...SLOWLY
DECREASING FLOW...AND A FRESH SNOWPACK ALL LOOK TO STILL COLLOCATE
FOR A VERY CHILLY NIGHT. HAVE MINS STILL IN THE -11 TO -18 ARENA
ACROSS ALL OF NORTH CENTRAL IL. HAVE HOISTED A WIND CHILL ADVISORY
AS WINDS WILL MAINTAIN ENOUGH FLOW TO MAKE IT DANGEROUS FOR ANY
PROLONGED EXPOSE SKIN.
FOR THIS WEEKEND WE CONTINUE TO WATCH A SYSTEM OF INTEREST. THE NEXT
IN A SERIES OF COLD FRONTS IS EXPECTED TO PASS SATURDAY AFTERNOON
WITH THE CHANCE FOR LIGHT SNOW. THE SLOWER EC HAS BEEN FOLLOWED
WHICH KEEPS THIS CHANCE OF SNOW AREAWIDE MAINLY DURING THE LATE
AFTERNOON AND NIGHT. AS THE NEXT UPPER TROUGH DEEPENS TO OUR
WEST...MUCH LIKE YESTERDAY...THAT WILL ENHANCE THE BAROCLINIC ZONE
OVER THE REGION POTENTIALLY PROVIDING FOR A FOCUS FOR SNOW LATER
SATURDAY NIGHT INTO SUNDAY. DO HAVE SOME LIKELY POPS IN THE
SOUTHEAST FORECAST AREA...BUT KNOWING THAT SHIFTS ARE INEVITABLE
WITH THIS HAVE NOT TRIED TO GET TOO FANCY. AT THIS TIME IT APPEARS
CHICAGO MAY BE GRAZED WITH THIS.
MTF
MONDAY THROUGH WEDNESDAY...
MAJOR ARCTIC BLAST ARRIVES EARLY MONDAY MORNING...WITH THE LATEST
GUIDANCE SHOWING NO SIGNS OF BACKING OFF ON THE DANGEROUSLY COLD
LOWS AND HIGH TEMPS FOR THE THE MON/TUE TIME FRAME.
ENSEMBLES FOR OVER A WEEK NOW HAVE INDICATED AN ARCTIC BLAST
ARRIVING FOR THE START OF NEXT WEEK...AND THIS CONTINUES TO BE THE
THEME. THE 500MB TROUGH AXIS ARRIVES OVER THE GREAT LAKES REGION
MON...AND WITH WEAK RIDGING OVER THE WESTERN ATLANTIC OCEAN
STRETCHING NORTH THROUGH THE CANADIAN MARITIME. THIS RIDGING WILL
LIKELY SLOW THE FORWARD PROGRESSION TO THE TROUGH AXIS...ALLOWING IT
TO LINGER LONGER OVER THE GREAT LAKES INTO TUE. THEN HEADING INTO
WED THE RIDGING OVER THE WESTERN ATLANTIC BEGINS TO PUSH
EAST...WHICH WILL ALLOW FOR A RELATIVELY MORE FLUID ATMOSPHERE AND
THE TROUGH AXIS WILL DRIFT EAST/NORTHEAST TOWARDS NEW ENGLAND.
AS PREVIOUSLY NOTED ABOUT THE COLD AIR...ENSEMBLES FOR NUMEROUS DAYS
HAVE BEEN PAINTING A HIGH CONFIDENCE THAT AT 850MB TEMPS BY EARLY
MON WILL BE ARND -24 TO -28 DEG C...WITH A POCKET OF -30 DEG C JUST
NORTH OF THE FORECAST AREA INTO CENTRAL/NORTHERN WISC. WITH THE SLOW
FORWARD PROPAGATION TO THE MID-LVL TROUGH...THIS WILL LIKELY KEEP
THE POTENT THERMAL TROUGH OVERHEAD INTO TUE. CLOSER TO THE SFC
RIDGING IS EXPECTED TO PUSH IN BEHIND THE ARCTIC FRONTAL BOUNDARY
AND PROVIDE RELATIVELY LITTLE IN THE WAY OF PRECIP TO THE FORECAST
AREA MON/TUE. UNFORTUNATELY WITH HOW COLD TEMPS WILL BE ALOFT AND A
THICK BLANKET OF SNOW...SFC TEMPS WILL EASILY HOLD WELL BELOW ZERO
FOR HIGHS BOTH MON/TUE. AT THIS TIME HIGH TEMPS MAY STRUGGLE ON BOTH
DAYS TO REACH -5 DEG F...WITH POSSIBLY A FEW LOCATIONS IN OUR
WESTERN CWFA STRUGGLING TO REACH -10 DEG C MON AFTN.
DEPENDING ON CLOUD COVER...OVERNIGHT LOWS COULD EASILY APPROACH
RECORD LOWS AT -15 TO -20 DEG F IN THIS TIMEFRAME. THE COMBINATION
OF DANGEROUSLY COLD SFC TEMPS...AND A GRADIENT PRODUCING BREEZY
CONDITIONS...WILL SET THE STAGE FOR WIND CHILL VALUES LIKELY TO
EXCEED -30 BELOW AND POSSIBLY APPROACH -40 DEG MON NGT. THE
GRADIENT SLACKENS FOR TUE NGT...HOWEVER WIND CHILL VALUES WILL ONCE
AGAIN APPROACH -20 TO -30 DEG F.
THEN TOWARDS THE MIDDLE OF NEXT WEEK THE TROUGH AXIS PIVOTS
EAST...WITH FLOW TURNING SOUTH/SOUTHWEST AND ADVECTING MUCH WARMER
AIR INTO THE REGION. ENSEMBLES HAVE CONTINUED TO INDICATE RELATIVELY
HIGH CONFIDENCE IN THE LONGER TERM PERIODS...WITH A MID-LVL TROUGH
DIGGING INTO THE SOUTHERN PLAINS AND POSSIBLY LEADING TO YET ANOTHER
ACTIVE PERIOD OF WEATHER FOR THE MIDDLE OF NEXT WEEK.
CONFIDENCE IN TEMPS MON/TUE...HIGH.
CONFIDENCE IN WIND CHILL VALUES MON/TUE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* CIG/VSBY TRENDS THROUGH EARLY AFTERNOON WITH LAKE EFFECT SNOW.
* VARIABLE NORTH-NORTHWEST TO NORTH-NORTHEAST WINDS TRENDING
NORTH-NORTHWEST LATE THIS MORNING AT ORD...AND THIS AFTERNOON
AT MDW.
MDB/BMD
//DISCUSSION...UPDATED 14Z...
LAKE EFFECT SNOW CONTINUES TO EVOLVE WITH THE STEADIER WIDESPREAD
SNOW OF THE PAST FEW HOURS BEGINNING TO TRANSITION TO A MORE
CELLULAR AND NARROW BAND. 14Z RADAR IMAGERY SHOWS THE
BROADER/STEADIER SNOW BAND PIVOTING EASTWARD TOWARD THE GYY AREA
WITH THE NEWLY DEVELOPING NARROW/CELLULAR BAND SETTING UP FROM THE
WISCONSIN SHORELINE SOUTHWARD TO BETWEEN ORD/DPA DOWN TO JOT. AM
THINKING THAT THIS BAND MAY BECOME MORE FOCUSED IN THIS GENERAL
AREA THEN GRADUALLY PIVOT EASTWARD. THIS MORE FOCUSED BAND MAY BE
SURROUNDED BY A LARGER AREA OF LESS FOCUSED SNOW KEEPING SNOW
SHOWERS ACROSS A LARGER AREA. THE MAIN CHALLENGE WILL BE
DETERMINING HOW LONG IT WILL TAKE FOR THE MORE INTENSE SNOW TO
SHIFT EAST OF ORD/MDW...WITH DPA APPEARING TO BE JUST TO THE WEST
OF THE MAIN ACTIVITY. MAY NEED TO LOWER VSBY INTO THE 1/2SM RANGE
FOR A TIME DURING THE LATE MORNING AT ORD/MDW. GYY SHOULD START
TO SEE STEADIER SNOW WITH THE MAIN BAND ARRIVING MIDDAY/EARLY
AFTERNOON.
MDB
FROM 12Z...
A PRONOUNCED BAND OF LAKE EFFECT SNOW DEVELOPED DURING THE
PREDAWN HOURS AND WAS POSITIONED OVER THE CHICAGO METRO AREA
AROUND DAYBREAK. FLIGHT CONDITIONS WILL LIKELY REMAIN IFR THIS
MORNING DUE MAINLY TO VSBY RESTRICTIONS BUT PERIODS OF IFR CIGS
ARE ALSO POSSIBLE. DESPITE THE PERSISTENCE OF THIS BAND...HAVE
MOSTLY BEEN SEEING MVFR VSBYS WITH OCCASIONAL IFR...SO ELECTED TO
LEAN TOWARD THAT TREND IN LATEST UPDATES RATHER THAN MAINTAINING
THE LIFR FROM EARLIER FORECASTS. THIS DOES NOT MEAN LIFR IS
COMPLETELY OUT OF THE QUESTION...JUST THAT IT IS NOT EXPECTED TO
BE THE PREVAILING CONDITION FOR AN EXTENDED PERIOD OF TIME.
ACCUMULATING SNOW STILL IS EXPECTED TO WRAP UP BY MID AFTERNOON AT
THE ORD/MDW TERMINALS AS WINDS TURN NORTHWEST AND THE BAND SLIDES
SOUTH. FLURRIES ARE POSSIBLE INTO THE EVENING...THEN HIGH
PRESSURE MOVES INTO THE AREA TONIGHT.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM CONFIDENCE IN SOME IMPROVEMENT AT ORD IN NEXT COUPLE
HOURS...LOW CONFIDENCE ON VSBY TRENDS AT MDW.
* MEDIUM-HIGH CONFIDENCE IN WIND TRENDS.
MDB/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...SNOW SHOWERS ARRIVE AFTERNOON...MVFR/IFR LIKELY.
SUNDAY...CHANCE SNOW SHOWERS AND MVFR/IFR.
MONDAY AND TUESDAY...BREEZY AND VFR...SOME MVFR POSSIBLE MONDAY.
WEDNESDAY...SNOW AND IFR POSSIBLE.
LENNING
&&
.MARINE...
326 AM CST
MAIN CONCERN IS STRONG LOW PRESSURE PASSING NORTH OF THE LAKES
FRIDAY NIGHT. LATEST MODELS CONTINUE THE TREND OF INCREASING WINDS
AND GUSTS FRIDAY NIGHT...SO ELECTED TO REPLACE THE GALE WATCH WITH
A STORM WATCH. REGARDLESS OF THE EXACT TRACK AND STRENGTH OF THE
LOW...FEEL FAIRLY CONFIDENT OF SEEING AT LEAST A PERIOD OF STORM
FORCE GUSTS...BUT NOT QUITE CONFIDENT ENOUGH YET TO GO WITH THE
WARNING. THESE STORM FORCE WINDS WOULD BE PRECEEDED BY GALES
FRIDAY AFTERNOON AND FOLLOWED BY GALES SATURDAY...BUT WILL CARRY
JUST A STORM WATCH FOR THE ENTIRE PERIOD TO AVOID COMPLICATING THE
HEADLINES.
IN THE NEARSHORE...GALES LIKELY WILL DEVELOP LATE FRIDAY INTO
SATURDAY DURING THE SAME PERIOD AS THE STORM FORCE WINDS IN THE
OPEN WATERS. SMALL CRAFT ADVISORIES CURRENTLY IN EFFECT DO LOOK
LIKE THEY CAN BE DROPPED FOR A SHORT TIME EARLY ON FRIDAY BEFORE
CONDITIONS RAPIDLY INCREASE AGAIN. TO DRAW ATTENTION TO THE SHORT
BREAK BEFORE THE NEW SYSTEM APPROACHING FRIDAY...AND TO AVOID
RUNNING THE HEADLINES TOGETHER...ELECTED TO HOLD OFF ON ISSUING A
GALE WATCH AT THIS TIME BUT DID MENTION IT IN THE FORECAST TEXT.
LENNING
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...LAKE EFFECT SNOW WARNING...ILZ006 UNTIL 3 PM THURSDAY.
WIND CHILL ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ019-ILZ020-ILZ021-ILZ032...9 PM THURSDAY
TO 10 AM FRIDAY.
LAKE EFFECT SNOW WARNING...ILZ013-ILZ014-ILZ022 UNTIL 6 PM
THURSDAY.
LAKE EFFECT SNOW ADVISORY...ILZ023 UNTIL 6 PM THURSDAY.
IN...LAKE EFFECT SNOW WARNING...INZ001-INZ002 UNTIL MIDNIGHT FRIDAY.
LAKE EFFECT SNOW ADVISORY...INZ010-INZ011 UNTIL MIDNIGHT FRIDAY.
LM...STORM WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...NOON FRIDAY TO 4 PM
SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 4 AM
FRIDAY.
SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 9 AM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
958 AM CST Thu Jan 2 2014
.DISCUSSION...
ISSUED 956 AM CST Thu Jan 2 2014
Have allowed the winter weather advisory to expire across eastern
Illinois. Still seeing some visibilities from 1 to 2 miles at
times, but several reports of unknown precipitation on automated
observations are likely implying areas of blowing snow.
Main concern the remainder of the day will be with lake effect
snow. Radar returns over central Illinois have been increasing the
last few hours as moisture is advected in from southern Lake
Michigan. Latest RAP model shows the broader stream of lake effect
snow in northeast Illinois becoming more focused this afternoon
and pushing southward toward Champaign and Danville as the wind
over the lake become more north-northeast. Have maintained 30-40
percent PoP`s in the far northeast CWA into the afternoon, but
will have to watch this closely as the RAP suggests another 1-2
inches may not be out of the question in those areas with this
type of fetch. Over the remainder of the forecast area,
precipitation should start taping off to flurries and end from
west to east.
Geelhart
&&
.AVIATION...
ISSUED 521 AM CST Thu Jan 2 2014
Snow in process of ending at KDEC and will likely end at KCMI by
14z as low pressure over southern Indiana continues moving away
from central Illinois. MVFR and occasional IFR Cigs will likely
persist even though associated mid-level trough moves across
Illinois around midday. Northeast flow will likely produce lake
effect snows over northeast Illinois and the moisture along with
occasional reductions in visibilities will likely reach as far
south as KBMI, KDEC, and of course KCMI. Will keep MVFR Cigs at
KPIA and KSPI without the snow shower threat.
Clearing is finally expected in the 02-05z window from west to
east as the surface high reaches central Illinois. Gusty north
winds today should diminish this evening.
Barker
&&
.PREV DISCUSSION...
ISSUED 330 AM CST Thu Jan 2 2014
SHORT TERM...Today through Sunday night
Winter will keep a tight grip over central and southeast IL during
the next week with arctic air masses visiting the region into the
middle of next week along with a couple of weather systems
bringing more snow. Will expire the winter weather advisory along
and northwest of I-55 with forecast package at 4 am and continue
the winter wx advisory until 9 am for east central and southeast IL.
Snowfall total have generally averaged 2-3 inches across central
IL with lesser amounts in our far southeast counties where mixed
precipitation occurred since it begin late Wed evening, plus a dry
slot in that area too keeping precipitation lighter. Still have
band of light snow from I-55 southeast which HRRR diminishes from
NW to SE through 15Z/9 am. Up to another inch of snow possible
east of I-55 with 1-2 inches more snow east of I-57. Gusty NNW
winds today to cause some low drifting across east-west roads.
Elongated 1013 mb low pressure from southern Indiana into NW TN
early this morning to eject quickly to the mid Atlantic coast by
sunset and produce a winter storm over the Northeast States into
Friday. Scattered flurries over even a few light snow showers
possible over eastern IL this afternoon especially over east
central IL but any additional snow accumulations should be
confined NE of our area closer to the Great Lakes region. Highs
today range from 10-15F over the IL river valley, to the low to
mid 20s in southeast IL.
Will issue a wind chill advisory along and NW of a Rushville to
Bloomington/Normal line tonight and Friday morning for wind chills
getting down to 15-20 below zero. 1037 mb arctic high pressure
over the eastern Dakotas and NW MN to settle into the mid MS
valley Friday morning and bring very cold temps back into the
region. Clouds to decrease from west to east during tonight and
winds to also diminish allowing temps to drop into the single
digits below zero over central IL with Galesburg 10 below or even
colder. High pressure drifts east into the mid Atlantic states by
Friday evening with increasing south winds and fair amount of
sunshine but still cold highs in the upper teens and lower 20s
with fresh snow cover. Breezy south winds continue Sat with milder
temps in the low to mid 30s. Also have 20-40% chance of light snow
from I-55 NW during Sat afternoon with next wx system approaching.
Strong upper level trof to dig into the Midwest by Sunday with low
pressure ejecting NE from the southern plains into the eastern
great lakes region as it deepens. Snow to develop across central
IL Sat night and continue Sunday with be heaviest in southeast IL
where several inches of snow possible. Areas NW by the IL river
valley appear to be on NW fringe of this storm system with lighter
snow amounts. Snow to diminish during Sunday night as storm system
pulls away.
LONG TERM...Monday through Wednesday night
The coldest air of the season still slated to arrive early next
work with from Sunday night through Tue night with subzero lows
returning to central and even southeast IL by Monday night with
northern areas 10-15 below zero. Wind chills Monday night into Tue
morning to get to 20-35 below zero and coldest from I-74 north.
Flurries possible over eastern IL Monday with deep upper level
trof in place. Then next weather system appears to arrive by Wed
afternoon into Thu with next chance of snow with light snow
accumulations possible then. Models trending upward with temps
later next week as upper level heights rise, but skeptical about
too fast of warmup with snow pack in place.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY from 6 PM this evening to Noon CST Friday
FOR ILZ027>031-036>038-040-041.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
600 AM CST THU JAN 2 2014
.DISCUSSION...
352 AM CST
SNOW AND COLD ONCE AGAIN ARE THE REPETITIVE HEADLINES TO THIS
FORECAST...AND IN FACT ARE THE HEADLINES THAT WE HAVE IN EFFECT.
THERE ARE LAKE EFFECT SNOW HEADLINES FOR TODAY ACROSS NORTHEAST IL
AND INTO NORTHWEST INDIANA TONIGHT...WITH SOME ADJUSTMENTS DONE FOR
TIMING AS WELL AS ADDING COUNTIES FOR AN ADVISORY. A WIND CHILL
ADVISORY HAS BEEN ISSUED FOR TONIGHT INTO FRIDAY MORNING FOR MUCH OF
NORTH CENTRAL AND PARTS OF NORTHEAST IL.
THE MASSIVE UPPER LEVEL TROUGH AND ITS EXPANSIVE COLD DEEP AIR
/500MB TEMPS NEARING -40C IN THE GREAT LAKES REGION/ REMAIN
ESTABLISHED OVER THE AREA. THIS IS EVEN SEEN ON THE HEMISPHERIC
WATER VAPOR IMAGERY THIS MORNING WITH A VERY EVIDENT DEEP ROSBY WAVE
CENTERED FROM HUDSON BAY TO GREENLAND AND EXTENDING ACROSS
CENTRAL/EASTERN NORTH AMERICA. PRONOUNCED JET AND UPPER SHORT WAVE
IS ROUNDING THE BASE OF THIS TROUGH ACROSS THE LOWER OHIO VALLEY
EARLY THIS MORNING. THIS WAS THE MAIN CAUSE OF OUR SNOW YESTERDAY
AND THAT HAS ALL BUT SHIFTED EAST OUT OF THE AREA EARLY THIS
MORNING...SO WILL BE ABLE TO LET THE WINTER WEATHER ADVISORY END AT
6 AM.
LOW PRESSURE OF 1013MB IS DEEPENING ACROSS TENNESSEE EARLY THIS
MORNING AND THAT WILL FURTHER DO SUCH INTO THE MID-ATLANTIC BY EARLY
EVE. WITH THE STRONG ARCTIC HIGH BUILDING INTO THE PLAINS...THIS
OVERALL PRESSURE EVOLUTION WILL FAVOR GRADUALLY VEERING WINDS ACROSS
THE LAKE. THIS SLOW VEERING WILL LIKELY HELP TO KEEP A MESOSCALE LOW
PRESSURE TROUGH/CONVERGENCE AXIS INTACT ACROSS THE FAR WESTERN PART
OF THE LAKE THROUGH THE MORNING. THIS AXIS EARLY THIS MORNING IS
ABOUT 35 MILES INLAND ACROSS NORTHEAST IL...BUT WILL SHIFT BACK OUT
TOWARD THE LAKE SHORE...LIKELY TOWARD MIDDAY AND BE THE FOCUS FOR
THE HEAVIEST LAKE EFFECT SNOW AND A LIKELY COUPLE/FEW HOUR PERIOD OF
VERY HEAVY RATES GIVEN THE VERY FAVORABLE PARAMETERS. THESE INCLUDE
STRONG LAKE-INDUCED INSTABILITY IN EXCESS OF 500 J/KG...THIS
INSTABILITY MAINLY COLLOCATED WITH SUPERSATURATION WITH RESPECT TO
ICE AND WITHIN THE DENDRITIC GROWTH AREA...AND CLOUD DEPTHS OF
9-10KFT. ALL THIS HAS BEEN CONSISTENTLY SHOWN BY THE NAM AND LOCAL
ARW.
PRIOR TO THIS AXIS...GENERAL ONSHORE FLOW INTO NORTHEAST IL HAS
ENOUGH INSTABILITY WITH IT TO BE DEVELOPING WIDESPREAD LAKE EFFECT
SNOW SHOWERS THIS MORNING...AND THESE ACTUALLY EXTEND AS FAR WEST IN
ILLINOIS AS ROCHELLE AND MENDOTA! A LONGER FETCH OF INSTABILITY IS
GRADUALLY WORKING INTO LAKE COUNTY IL FROM THE NORTH AND BASED ON
OBSERVATIONS OF LOWERING VISIBILITIES TO AT OR UNDER A
MILE...ACCUMULATIONS OF AROUND ONE HALF INCH PER HOUR WILL SLOWLY
SPREAD SOUTH. SO GIVEN THAT SNOW SHOWERS ARE ALREADY ONGOING WITH
PARAMETERS ONLY BETTERING...SEE NO REASON SNOW SHOWERS WILL NOT STOP
FOR NORTHEAST IL UNTIL THE FLOW TURNS OFFSHORE. THE HEAVIEST SNOW
AGAIN WILL BE CONFINED TO NEAR THAT CONVERGENT AXIS AND USING OUR
LOCAL 8KM ARW...THAT LOOKS TO LINE ITSELF INTO DOWNTOWN CHICAGO
DURING THE EARLY TO MID AFTERNOON...BEFORE SHIFTING EASTWARD INTO
NORTHWEST IN. THIS TIMING OF THE PROBABLE HEAVIEST RATES AND
DURATION IN WHICH THEY LAST...WILL LIKELY BE DEPENDENT ON IF A
MESOSCALE CIRCULATION CAN REMAIN INTACT OVER THE FAR SOUTHERN PART OF
THE LAKE TOO...BASICALLY SLOWLY THAT EASTWARD PROGRESSION. THE
LONGER THAT DOES SUCH...THE MORE PROBABLE THAT SOME CORRIDOR OF THE
LAKE EFFECT WARNING WILL REALIZE 6 OR MORE...POSSIBLY EVEN 8-10
INCHES OF SNOW. THE CONVERGENCE BEGINS TO WEAKEN LATE THIS EVENING
INTO NORTHWEST INDIANA AS IT CONTINUES TO PIVOT EAST...SO THAT
RESULTS IN SNOW ENDING FROM WEST TO EAST ACROSS ADJACENT COUNTIES TO
SOUTHERN LAKE MICHIGAN.
MODEL GUIDANCE REMAINS IN STRONG AGREEMENT WITH ANTICYCLONIC FLOW IN
THE LOW-LEVELS AND SUPPRESSION ALOFT DISSIPATING CLOUDS QUICKLY FROM
WEST TO EAST ACROSS NORTHERN IL LATE THIS AFTERNOON AND THIS EVE.
RADIATIONAL COOLING...HIGHLY ANOMALOUS COLD ATMOSPHERIC AIR...SLOWLY
DECREASING FLOW...AND A FRESH SNOWPACK ALL LOOK TO STILL COLLOCATE
FOR A VERY CHILLY NIGHT. HAVE MINS STILL IN THE -11 TO -18 ARENA
ACROSS ALL OF NORTH CENTRAL IL. HAVE HOISTED A WIND CHILL ADVISORY
AS WINDS WILL MAINTAIN ENOUGH FLOW TO MAKE IT DANGEROUS FOR ANY
PROLONGED EXPOSE SKIN.
FOR THIS WEEKEND WE CONTINUE TO WATCH A SYSTEM OF INTEREST. THE NEXT
IN A SERIES OF COLD FRONTS IS EXPECTED TO PASS SATURDAY AFTERNOON
WITH THE CHANCE FOR LIGHT SNOW. THE SLOWER EC HAS BEEN FOLLOWED
WHICH KEEPS THIS CHANCE OF SNOW AREAWIDE MAINLY DURING THE LATE
AFTERNOON AND NIGHT. AS THE NEXT UPPER TROUGH DEEPENS TO OUR
WEST...MUCH LIKE YESTERDAY...THAT WILL ENHANCE THE BAROCLINIC ZONE
OVER THE REGION POTENTIALLY PROVIDING FOR A FOCUS FOR SNOW LATER
SATURDAY NIGHT INTO SUNDAY. DO HAVE SOME LIKELY POPS IN THE
SOUTHEAST FORECAST AREA...BUT KNOWING THAT SHIFTS ARE INEVITABLE
WITH THIS HAVE NOT TRIED TO GET TOO FANCY. AT THIS TIME IT APPEARS
CHICAGO MAY BE GRAZED WITH THIS.
MTF
MONDAY THROUGH WEDNESDAY...
MAJOR ARCTIC BLAST ARRIVES EARLY MONDAY MORNING...WITH THE LATEST
GUIDANCE SHOWING NO SIGNS OF BACKING OFF ON THE DANGEROUSLY COLD
LOWS AND HIGH TEMPS FOR THE THE MON/TUE TIME FRAME.
ENSEMBLES FOR OVER A WEEK NOW HAVE INDICATED AN ARCTIC BLAST
ARRIVING FOR THE START OF NEXT WEEK...AND THIS CONTINUES TO BE THE
THEME. THE 500MB TROUGH AXIS ARRIVES OVER THE GREAT LAKES REGION
MON...AND WITH WEAK RIDGING OVER THE WESTERN ATLANTIC OCEAN
STRETCHING NORTH THROUGH THE CANADIAN MARITIME. THIS RIDGING WILL
LIKELY SLOW THE FORWARD PROGRESSION TO THE TROUGH AXIS...ALLOWING IT
TO LINGER LONGER OVER THE GREAT LAKES INTO TUE. THEN HEADING INTO
WED THE RIDGING OVER THE WESTERN ATLANTIC BEGINS TO PUSH
EAST...WHICH WILL ALLOW FOR A RELATIVELY MORE FLUID ATMOSPHERE AND
THE TROUGH AXIS WILL DRIFT EAST/NORTHEAST TOWARDS NEW ENGLAND.
AS PREVIOUSLY NOTED ABOUT THE COLD AIR...ENSEMBLES FOR NUMEROUS DAYS
HAVE BEEN PAINTING A HIGH CONFIDENCE THAT AT 850MB TEMPS BY EARLY
MON WILL BE ARND -24 TO -28 DEG C...WITH A POCKET OF -30 DEG C JUST
NORTH OF THE FORECAST AREA INTO CENTRAL/NORTHERN WISC. WITH THE SLOW
FORWARD PROPAGATION TO THE MID-LVL TROUGH...THIS WILL LIKELY KEEP
THE POTENT THERMAL TROUGH OVERHEAD INTO TUE. CLOSER TO THE SFC
RIDGING IS EXPECTED TO PUSH IN BEHIND THE ARCTIC FRONTAL BOUNDARY
AND PROVIDE RELATIVELY LITTLE IN THE WAY OF PRECIP TO THE FORECAST
AREA MON/TUE. UNFORTUNATELY WITH HOW COLD TEMPS WILL BE ALOFT AND A
THICK BLANKET OF SNOW...SFC TEMPS WILL EASILY HOLD WELL BELOW ZERO
FOR HIGHS BOTH MON/TUE. AT THIS TIME HIGH TEMPS MAY STRUGGLE ON BOTH
DAYS TO REACH -5 DEG F...WITH POSSIBLY A FEW LOCATIONS IN OUR
WESTERN CWFA STRUGGLING TO REACH -10 DEG C MON AFTN.
DEPENDING ON CLOUD COVER...OVERNIGHT LOWS COULD EASILY APPROACH
RECORD LOWS AT -15 TO -20 DEG F IN THIS TIMEFRAME. THE COMBINATION
OF DANGEROUSLY COLD SFC TEMPS...AND A GRADIENT PRODUCING BREEZY
CONDITIONS...WILL SET THE STAGE FOR WIND CHILL VALUES LIKELY TO
EXCEED -30 BELOW AND POSSIBLY APPROACH -40 DEG MON NGT. THE
GRADIENT SLACKENS FOR TUE NGT...HOWEVER WIND CHILL VALUES WILL ONCE
AGAIN APPROACH -20 TO -30 DEG F.
THEN TOWARDS THE MIDDLE OF NEXT WEEK THE TROUGH AXIS PIVOTS
EAST...WITH FLOW TURNING SOUTH/SOUTHWEST AND ADVECTING MUCH WARMER
AIR INTO THE REGION. ENSEMBLES HAVE CONTINUED TO INDICATE RELATIVELY
HIGH CONFIDENCE IN THE LONGER TERM PERIODS...WITH A MID-LVL TROUGH
DIGGING INTO THE SOUTHERN PLAINS AND POSSIBLY LEADING TO YET ANOTHER
ACTIVE PERIOD OF WEATHER FOR THE MIDDLE OF NEXT WEEK.
CONFIDENCE IN TEMPS MON/TUE...HIGH.
CONFIDENCE IN WIND CHILL VALUES MON/TUE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* CIG AND VSBY TRENDS AND SNOW AMOUNTS RELATED TO LAKE EFFECT
SNOW BAND.
* WINDS TURNING FROM NORTHEAST TO NORTH NORTHWEST.
LENNING
//DISCUSSION...UPDATED 12Z...
A PRONOUNCED BAND OF LAKE EFFECT SNOW DEVELOPED DURING THE
PREDAWN HOURS AND WAS POSITIONED OVER THE CHICAGO METRO AREA
AROUND DAYBREAK. FLIGHT CONDITIONS WILL LIKELY REMAIN IFR THIS
MORNING DUE MAINLY TO VSBY RESTRICTIONS BUT PERIODS OF IFR CIGS
ARE ALSO POSSIBLE. DESPITE THE PERSISTENCE OF THIS BAND...HAVE
MOSTLY BEEN SEEING MVFR VSBYS WITH OCCASIONAL IFR...SO ELECTED TO
LEAN TOWARD THAT TREND IN LATEST UPDATES RATHER THAN MAINTAINING
THE LIFR FROM EARLIER FORECASTS. THIS DOES NOT MEAN LIFR IS
COMPLETELY OUT OF THE QUESTION...JUST THAT IT IS NOT EXPECTED TO
BE THE PREVAILING CONDITION FOR AN EXTENDED PERIOD OF TIME.
ACCUMULATING SNOW STILL IS EXPECTED TO WRAP UP BY MID AFTERNOON AT
THE ORD/MDW TERMINALS AS WINDS TURN NORTHWEST AND THE BAND SLIDES
SOUTH. FLURRIES ARE POSSIBLE INTO THE EVENING...THEN HIGH
PRESSURE MOVES INTO THE AREA TONIGHT.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH CONFIDENCE OF IFR VSBYS THIS MORNING. MEDIUM CONFIDENCE OF
SEEING MORE MVFR THAN LIFR.
* MEDIUM CONFIDENCE IN CEILING TRENDS...AGAIN MAINLY MVFR.
* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...SNOW SHOWERS ARRIVE AFTERNOON...MVFR/IFR LIKELY.
SUNDAY...CHANCE SNOW SHOWERS AND MVFR/IFR.
MONDAY AND TUESDAY...BREEZY AND VFR...SOME MVFR POSSIBLE MONDAY.
WEDNESDAY...SNOW AND IFR POSSIBLE.
LENNING
&&
.MARINE...
326 AM CST
MAIN CONCERN IS STRONG LOW PRESSURE PASSING NORTH OF THE LAKES
FRIDAY NIGHT. LATEST MODELS CONTINUE THE TREND OF INCREASING WINDS
AND GUSTS FRIDAY NIGHT...SO ELECTED TO REPLACE THE GALE WATCH WITH
A STORM WATCH. REGARDLESS OF THE EXACT TRACK AND STRENGTH OF THE
LOW...FEEL FAIRLY CONFIDENT OF SEEING AT LEAST A PERIOD OF STORM
FORCE GUSTS...BUT NOT QUITE CONFIDENT ENOUGH YET TO GO WITH THE
WARNING. THESE STORM FORCE WINDS WOULD BE PRECEEDED BY GALES
FRIDAY AFTERNOON AND FOLLOWED BY GALES SATURDAY...BUT WILL CARRY
JUST A STORM WATCH FOR THE ENTIRE PERIOD TO AVOID COMPLICATING THE
HEADLINES.
IN THE NEARSHORE...GALES LIKELY WILL DEVELOP LATE FRIDAY INTO
SATURDAY DURING THE SAME PERIOD AS THE STORM FORCE WINDS IN THE
OPEN WATERS. SMALL CRAFT ADVISORIES CURRENTLY IN EFFECT DO LOOK
LIKE THEY CAN BE DROPPED FOR A SHORT TIME EARLY ON FRIDAY BEFORE
CONDITIONS RAPIDLY INCREASE AGAIN. TO DRAW ATTENTION TO THE SHORT
BREAK BEFORE THE NEW SYSTEM APPROACHING FRIDAY...AND TO AVOID
RUNNING THE HEADLINES TOGETHER...ELECTED TO HOLD OFF ON ISSUING A
GALE WATCH AT THIS TIME BUT DID MENTION IT IN THE FORECAST TEXT.
LENNING
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...LAKE EFFECT SNOW WARNING...ILZ006 UNTIL 3 PM THURSDAY.
WIND CHILL ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ019-ILZ020-ILZ021-ILZ032...9 PM THURSDAY
TO 10 AM FRIDAY.
LAKE EFFECT SNOW WARNING...ILZ014 UNTIL 6 PM THURSDAY.
LAKE EFFECT SNOW ADVISORY...ILZ013-ILZ022 UNTIL 6 PM THURSDAY.
IN...LAKE EFFECT SNOW WARNING...INZ001 UNTIL MIDNIGHT FRIDAY.
LAKE EFFECT SNOW ADVISORY...INZ002...3 PM THURSDAY TO 4 AM
FRIDAY.
LM...STORM WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...NOON FRIDAY TO 4 PM
SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 4 AM
FRIDAY.
SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 9 AM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
527 AM CST Thu Jan 2 2014
.DISCUSSION...
ISSUED 330 AM CST Thu Jan 2 2014
SHORT TERM...Today through Sunday night
Winter will keep a tight grip over central and southeast IL during
the next week with arctic airmasses visiting the region into the
middle of next week along with a couple of weather systems
bringing more snow. Will expire the winter weather advisory along
and northwest of I-55 with forecast package at 4 am and continue
the winter wx advisory until 9 am for eastcentral and southeast IL.
Snowfall total have generally averaged 2-3 inches acorss central
IL with lesser amounts in our far southeast counties where mixed
precipitation occurred since it begin late Wed evening, plus a dry
slot in that area too keeping precipitation lighter. Still have
band of light snow from I-55 southeast which HRRR diminishes from
nw to se through 15Z/9 am. Up to another inch of snow possible
east of I-55 with 1-2 inches more snow east of I-57. Gusty nnw
winds today to cause some low drifting across east-west roads.
Elongated 1013 mb low pressure from southern Indiana into NW TN
early this morning to eject quickly to the mid Atlantic coast by
sunset and produce a winter storm over the Northeast States into
Friday. Scattered flurries over even a few light snow showers
possible over eastern IL this afternoon especially over east
central IL but any additional snow accumulations should be
confined ne of our area closer to the Great Lakes region. Highs
today range from 10-15F over the IL river valley, to the low to
mid 20s in southeast IL.
Will issue a wind chill advisory along and nw of a Rushville to
Bloomington/Normal line tonight and Friday morning for wind chills
getting down to 15-20 below zero. 1037 mb arctic high pressure
over the eastern Dakotas and nw MN to settle into the mid MS
valley Friday morning and bring very cold temps back into the
region. Clouds to decrease from west to east during tonight and
winds to also diminish allowing temps to drop into the single
digits below zero over central IL with Galesburg 10 below or even
colder. High pressure drifts east into the mid Atlantic states by
Friday evening with increaing south winds and fair amount of
sunshine but still cold highs in the upper teens and lower 20s
with fresh snow cover. Breezy south winds continue Sat with milder
temps in the low to mid 30s. Also have 20-40% chance of light snow
from I-55 nw during Sat afternoon with next wx system approaching.
Strong upper level trof to dig into the Midwest by Sunday with low
pressure ejecting ne from the southern plains into the eastern
great lakes region as it deepens. Snow to develop across central
IL Sat night and continue Sunday with be heaviest in southeast IL
where several inches of snow possible. Areas nw by the IL river
valley appear to be on nw fringe of this storm system with ligher
snow amounts. Snow to diminish during Sunday night as storm system
pulls away.
LONG TERM...Monday through Wednesday night
The coldest air of the season still slated to arrive early next
work with from Sunday night through Tue night with subzero lows
returning to central and even southeast IL by Monday night with
northern areas 10-15 below zero. Wind chills Monday night into Tue
morning to get to 20-35 below zero and coldest from I-74 north.
Flurries possible over eastern IL monday with deep upper level
trof in place. Then next weather system appears to arrive by Wed
afternoon into Thu with next chance of snow with light snow
accumulations possible then. Models trending upward with temps
later next week as upper level heights rise, but skeptical about
too fast of warmup with snow pack in place.
07
&&
.AVIATION...
ISSUED 521 AM CST Thu Jan 2 2014
Snow in process of ending at KDEC and will likely end at KCMI by
14z as low pressure over southern Indiana continues moving away
from central Illinois. MVFR and occasional IFR Cigs will likely
persist even though associated mid-level trough moves across
Illinois around midday. Northeast flow will likely produce lake
effect snows over northeast Illinois and the moisture along with
occasional reductions in visibilities will likely reach as far
south as KBMI, KDEC, and of course KCMI. Will keep MVFR Cigs at
KPIA and KSPI without the snow shower threat.
Clearing is finally expected in the 02-05z window from west to
east as the surface high reaches central Illinois. Gusty north
winds today should diminish this evening.
Barker
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY until 9 AM CST this morning FOR
ILZ044>046-054>057-061>063-066>068-071>073.
WIND CHILL ADVISORY from 6 PM this evening to Noon CST Friday
FOR ILZ027>031-036>038-040-041.
WINTER WEATHER ADVISORY until 6 AM CST early this morning FOR
ILZ043-052-053.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
352 AM CST THU JAN 2 2014
.DISCUSSION...
212 AM CST
SHORT TERM FORECAST WILL BE ARRIVING SHORTLY...
MONDAY THROUGH WEDNESDAY...
MAJOR ARCTIC BLAST ARRIVES EARLY MONDAY MORNING...WITH THE LATEST
GUIDANCE SHOWING NO SIGNS OF BACKING OFF ON THE DANGEROUSLY COLD
LOWS AND HIGH TEMPS FOR THE THE MON/TUE TIMEFRAME.
ENSEMBLES FOR OVER A WEEK NOW HAVE INDICATED AN ARCTIC BLAST
ARRIVING FOR THE START OF NEXT WEEK...AND THIS CONTINUES TO BE THE
THEME. THE 500MB TROUGH AXIS ARRIVES OVER THE GREAT LAKES REGION
MON...AND WITH WEAK RIDGING OVER THE WESTERN ATLANTIC OCEAN
STRETCHING NORTH THROUGH THE CANADIAN MARITIME. THIS RIDGING WILL
LIKELY SLOW THE FORWARD PROGRESSION TO THE TROUGH AXIS...ALLOWING IT
TO LINGER LONGER OVER THE GREAT LAKES INTO TUE. THEN HEADING INTO
WED THE RIDGING OVER THE WESTERN ATLANTIC BEGINS TO PUSH
EAST...WHICH WILL ALLOW FOR A RELATIVELY MORE FLUID ATMOSPHERE AND
THE TROUGH AXIS WILL DRIFT EAST/NORTHEAST TOWARDS NEW ENGLAND.
AS PREVIOUSLY NOTED ABOUT THE COLD AIR...ENSEMBLES FOR NUMEROUS DAYS
HAVE BEEN PAINTING A HIGH CONFIDENCE THAT AT 850MB TEMPS BY EARLY
MON WILL BE ARND -24 TO -28 DEG C...WITH A POCKET OF -30 DEG C JUST
NORTH OF THE FORECAST AREA INTO CENTRAL/NORTHERN WISC. WITH THE SLOW
FORWARD PROPAGATION TO THE MID-LVL TROUGH...THIS WILL LIKELY KEEP
THE POTENT THERMAL TROUGH OVERHEAD INTO TUE. CLOSER TO THE SFC
RIDGING IS EXPECTED TO PUSH IN BEHIND THE ARCTIC FRONTAL BOUNDARY
AND PROVIDE RELATIVELY LITTLE IN THE WAY OF PRECIP TO THE FORECAST
AREA MON/TUE. UNFORTUNATELY WITH HOW COLD TEMPS WILL BE ALOFT AND A
THICK BLANKET OF SNOW...SFC TEMPS WILL EASILY HOLD WELL BELOW ZERO
FOR HIGHS BOTH MON/TUE. AT THIS TIME HIGH TEMPS MAY STRUGGLE ON BOTH
DAYS TO REACH -5 DEG F...WITH POSSIBLY A FEW LOCATIONS IN OUR
WESTERN CWFA STRUGGLING TO REACH -10 DEG C MON AFTN.
DEPENDING ON CLOUD COVER...OVERNIGHT LOWS COULD EASILY APPROACH
RECORD LOWS AT -15 TO -20 DEG F IN THIS TIMEFRAME. THE COMBINATION
OF DANGEROUSLY COLD SFC TEMPS...AND A GRADIENT PRODUCING BREEZY
CONDITIONS...WILL SET THE STAGE FOR WIND CHILL VALUES LIKELY TO
EXCEED -30 BELOW AND POSSIBLY APPROACH -40 DEG MON NGT. THE
GRADIENT SLACKENS FOR TUE NGT...HOWEVER WIND CHILL VALUES WILL ONCE
AGAIN APPROACH -20 TO -30 DEG F.
THEN TOWARDS THE MIDDLE OF NEXT WEEK THE TROUGH AXIS PIVOTS
EAST...WITH FLOW TURNING SOUTH/SOUTHWEST AND ADVECTING MUCH WARMER
AIR INTO THE REGION. ENSEMBLES HAVE CONTINUED TO INDICATE RELATIVELY
HIGH CONFIDENCE IN THE LONGER TERM PERIODS...WITH A MID-LVL TROUGH
DIGGING INTO THE SOUTHERN PLAINS AND POSSIBLY LEADING TO YET ANOTHER
ACTIVE PERIOD OF WEATHER FOR THE MIDDLE OF NEXT WEEK.
CONFIDENCE IN TEMPS MON/TUE...HIGH.
CONFIDENCE IN WIND CHILL VALUES MON/TUE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* LIGHT TO MODERATE LAKE EFFECT SNOW INTO THE AFTERNOON WITH BRIEF
PERIODS OF HEAVIER SNOW AND IFR CIGS/VSBYS.
* NORTHEAST WINDS BECOMING NORTH-NORTHEAST BY MORNING THEN NORTH-
NORTHWEST BY AFTERNOON.
LENNING
//DISCUSSION...UPDATED 06Z...
LARGER SCALE SWATH OF SNOW HAS MOSTLY SLID SOUTH OF THE ORD/MDW
AREA BUT A BROAD LAKE EFFECT BAND IS SUPPORTING CONTINUED LIGHT
SNOW WITH BLOWING SNOW. EXPECT THIS BAND TO PERSIST INTO THE
MORNING AND LIKELY INTENSIFY AT TIMES WHILE GRADUALLY SHIFTING
FROM THE ILLINOIS SIDE TO THE INDIANA END AS WINDS BACK FROM
NORTHEAST TO NORTH NORTHEAST. THE PEAK PERIOD FOR MORE INTENSE
SNOWFALL AT THE ORD/MDW TERMINALS STILL APPEARS TO BE TOWARD
DAYBREAK INTO THE MORNING HOURS BEFORE ACTIVITY DROPS SOUTH.
AS PER THE PREVIOUS DISCUSSION...MODERATE TO HEAVY SNOW IS
POSSIBLE WITH 1/2 TO POTENTIALLY 1/4SM VSBY AT TIMES...WITH
SEVERAL INCHES OF ACCUMULATION DEPENDING ON HOW LONG THE BAND IS
OVERHEAD.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH CONFIDENCE OF ACCUMULATING LAKE EFFECT SNOW PERSISTING INTO
THE AFTERNOON. MEDIUM CONFIDENCE ON ENDING TIME AROUND 21-22Z.
* MEDIUM TO HIGH CONFIDENCE OF SEEING PERIODS OF IFR VSBYS. LOWER
CONFIDENCE OF LIFR TODAY.
* HIGH CONFIDENCE IN WIND TRENDS BECOMING NORTHWEST THIS AFTERNOON.
LENNING
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY...VFR.
SATURDAY...SNOW SHOWERS ARRIVE AFTERNOON...MVFR/IFR LIKELY.
SUNDAY...CHANCE SNOW SHOWERS AND MVFR/IFR.
MONDAY AND TUESDAY...BREEZY AND VFR...SOME MVFR POSSIBLE MONDAY.
MDB
&&
.MARINE...
326 AM CST
MAIN CONCERN IS STRONG LOW PRESSURE PASSING NORTH OF THE LAKES
FRIDAY NIGHT. LATEST MODELS CONTINUE THE TREND OF INCREASING WINDS
AND GUSTS FRIDAY NIGHT...SO ELECTED TO REPLACE THE GALE WATCH WITH
A STORM WATCH. REGARDLESS OF THE EXACT TRACK AND STRENGTH OF THE
LOW...FEEL FAIRLY CONFIDENT OF SEEING AT LEAST A PERIOD OF STORM
FORCE GUSTS...BUT NOT QUITE CONFIDENT ENOUGH YET TO GO WITH THE
WARNING. THESE STORM FORCE WINDS WOULD BE PRECEEDED BY GALES
FRIDAY AFTERNOON AND FOLLOWED BY GALES SATURDAY...BUT WILL CARRY
JUST A STORM WATCH FOR THE ENTIRE PERIOD TO AVOID COMPLICATING THE
HEADLINES.
IN THE NEARSHORE...GALES LIKELY WILL DEVELOP LATE FRIDAY INTO
SATURDAY DURING THE SAME PERIOD AS THE STORM FORCE WINDS IN THE
OPEN WATERS. SMALL CRAFT ADVISORIES CURRENTLY IN EFFECT DO LOOK
LIKE THEY CAN BE DROPPED FOR A SHORT TIME EARLY ON FRIDAY BEFORE
CONDITIONS RAPIDLY INCREASE AGAIN. TO DRAW ATTENTION TO THE SHORT
BREAK BEFORE THE NEW SYSTEM APPROACHING FRIDAY...AND TO AVOID
RUNNING THE HEADLINES TOGETHER...ELECTED TO HOLD OFF ON ISSUING A
GALE WATCH AT THIS TIME BUT DID MENTION IT IN THE FORECAST TEXT.
LENNING
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...LAKE EFFECT SNOW WARNING...ILZ006 UNTIL 3 PM THURSDAY.
WIND CHILL ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ019-ILZ020-ILZ021-ILZ032...9 PM THURSDAY
TO 10 AM FRIDAY.
LAKE EFFECT SNOW WARNING...ILZ014 UNTIL 6 PM THURSDAY.
WINTER WEATHER ADVISORY...ILZ013-ILZ022-ILZ023-ILZ032-ILZ033-
ILZ039 UNTIL 6 AM THURSDAY.
LAKE EFFECT SNOW ADVISORY...ILZ013-ILZ022 UNTIL 6 PM THURSDAY.
IN...LAKE EFFECT SNOW WARNING...INZ001 UNTIL MIDNIGHT FRIDAY.
WINTER WEATHER ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019
UNTIL 6 AM THURSDAY.
LAKE EFFECT SNOW ADVISORY...INZ002...3 PM THURSDAY TO 4 AM
FRIDAY.
LM...STORM WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...NOON FRIDAY TO 4 PM
SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 4 AM
FRIDAY.
SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 9 AM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
330 AM CST Thu Jan 2 2014
.DISCUSSION...
ISSUED 330 AM CST Thu Jan 2 2014
SHORT TERM...Today through Sunday night
Winter will keep a tight grip over central and southeast IL during
the next week with arctic airmasses visiting the region into the
middle of next week along with a couple of weather systems
bringing more snow. Will expire the winter weather advisory along
and northwest of I-55 with forecast package at 4 am and continue
the winter wx advisory until 9 am for eastcentral and southeast IL.
Snowfall total have generally averaged 2-3 inches acorss central
IL with lesser amounts in our far southeast counties where mixed
precipitation occurred since it begin late Wed evening, plus a dry
slot in that area too keeping precipitation lighter. Still have
band of light snow from I-55 southeast which HRRR diminishes from
nw to se through 15Z/9 am. Up to another inch of snow possible
east of I-55 with 1-2 inches more snow east of I-57. Gusty nnw
winds today to cause some low drifting across east-west roads.
Elongated 1013 mb low pressure from southern Indiana into NW TN
early this morning to eject quickly to the mid Atlantic coast by
sunset and produce a winter storm over the Northeast States into
Friday. Scattered flurries over even a few light snow showers
possible over eastern IL this afternoon especially over east
central IL but any additional snow accumulations should be
confined ne of our area closer to the Great Lakes region. Highs
today range from 10-15F over the IL river valley, to the low to
mid 20s in southeast IL.
Will issue a wind chill advisory along and nw of a Rushville to
Bloomington/Normal line tonight and Friday morning for wind chills
getting down to 15-20 below zero. 1037 mb arctic high pressure
over the eastern Dakotas and nw MN to settle into the mid MS
valley Friday morning and bring very cold temps back into the
region. Clouds to decrease from west to east during tonight and
winds to also diminish allowing temps to drop into the single
digits below zero over central IL with Galesburg 10 below or even
colder. High pressure drifts east into the mid Atlantic states by
Friday evening with increaing south winds and fair amount of
sunshine but still cold highs in the upper teens and lower 20s
with fresh snow cover. Breezy south winds continue Sat with milder
temps in the low to mid 30s. Also have 20-40% chance of light snow
from I-55 nw during Sat afternoon with next wx system approaching.
Strong upper level trof to dig into the Midwest by Sunday with low
pressure ejecting ne from the southern plains into the eastern
great lakes region as it deepens. Snow to develop across central
IL Sat night and continue Sunday with be heaviest in southeast IL
where several inches of snow possible. Areas nw by the IL river
valley appear to be on nw fringe of this storm system with ligher
snow amounts. Snow to diminish during Sunday night as storm system
pulls away.
LONG TERM...Monday through Wednesday night
The coldest air of the season still slated to arrive early next
work with from Sunday night through Tue night with subzero lows
returning to central and even southeast IL by Monday night with
northern areas 10-15 below zero. Wind chills Monday night into Tue
morning to get to 20-35 below zero and coldest from I-74 north.
Flurries possible over eastern IL monday with deep upper level
trof in place. Then next weather system appears to arrive by Wed
afternoon into Thu with next chance of snow with light snow
accumulations possible then. Models trending upward with temps
later next week as upper level heights rise, but skeptical about
too fast of warmup with snow pack in place.
07
&&
.AVIATION...
ISSUED 1137 PM CST Wed Jan 1 2014
Snow is beginning to taper off some in the northwest and should
affect PIA first, then BMI and SPI, followed by DEC and then
lastly CMI. IFR conditions still continue at all sites, but think
conditions will improve overnight in next 2-3 hours. So expecting
MVFR conditions at PIA at onset, at 08z for SPI and BMI, 09z at
DEC and 10z for CMI. Then VFR conditions a couple hours after
that, respectively. However, NAM model hangs on to some low level
moisture and flurries/light snow tomorrow from late morning into
the afternoon/evening in the east. So have added mention of light
snow or flurries at TAF sites, with lowest vis/cigs in east, and
longest as well. Then expecting clouds to scatter out as high
pressure area moves into the region for late tomorrow night. Winds
will be out of the north and increasing in wind speed as gradient
tightens overnight. North to northwest winds will continue through
tomorrow and be gusty. Gusty winds will decrease tomorrow evening
as gradient loosens, which will be around same time as clouds
scattering out.
Auten
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY until 9 AM CST this morning FOR
ILZ044>046-054>057-061>063-066>068-071>073.
WIND CHILL ADVISORY from 6 PM this evening to Noon CST Friday
FOR ILZ027>031-036>038-040-041.
WINTER WEATHER ADVISORY until 6 AM CST early this morning FOR
ILZ043-052-053.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1157 PM CST WED JAN 1 2014
.UPDATE...
ISSUED AT 1144 PM CST WED JAN 1 2014
THE WINTER WEATHER ADVISORY FOR THE SOUTHERN COUNTIES WILL BE
ALLOWED TO EXPIRE AT MIDNIGHT. THE REGIONAL RADAR COMPOSITES SHOW
THE BACK EDGE OF THE SNOW OVER THE FAR SOUTHEAST CORNER OF THE
CWFA WITH VSBYS AT MACOMB KMQB AT 7SM AS OF 1135 PM. THE SNOW CONTINUED
TO MOVE SOUTHEAST AND SHOULD BE OUT OF THE CWFA BY OR SHORTLY
AFTER MIDNIGHT. THE WIND CHILL ADVISORY FOR THE NORTHWEST HALF
REMAINS IN EFFECT.
UPDATE ISSUED AT 833 PM CST WED JAN 1 2014
ANOTHER ROW OF COUNTIES HAS BEEN DROPPED FROM THE NORTHERN EDGE OF
THE WINTER WEATHER ADVISORY AS THE AREA OF SNOW CONTINUES TO MOVE
SOUTHEAST.
UPDATE ISSUED AT 623 PM CST WED JAN 1 2014
TRENDS PER REGIONAL RADAR COMPOSITE SHOW THE BACK EDGE OF THE
ACCUMULATING SNOW FROM NEAR STERLING/ROCKFALLS THROUGH MOLINE AND
WASHINGTON IA AND MOVING STEADILY SOUTHEAST. THIS IS IN GOOD
AGREEMENT WITH THE 22Z RUN OF THE HRRR PRECIP FIELD. THE HRRR
SHOWS THE MEASURABLE SNOW CONTINUING TO PUSH STEADILY SOUTHEAST
THIS EVENING. WITH THESE TRENDS IN MIND THE PORTION OF THE WSW
THAT RAN UNTIL 6 PM WAS ALLOWED TO EXPIRE. SOME AREAS WHERE THE
WSW EXPIRED MAY SEE ANOTHER HOUR OR 2 OF LIGHT SNOW BUT ADDITIONAL
ACCUMULATIONS SHOULD BE WELL UNDER AN INCH. OTHERWISE NO CHANGES
WERE MADE TO THE REST OF THE FORECAST. WILL CONTINUE TO CHIP AWAY AT
THE NORTH EDGE OF THE REMAINING WINTER WX ADVISORY AS THE SNOW
CONTINUES TO MOVE SOUTHEAST.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 315 PM CST WED JAN 1 2014
WILL LEAVE ONGOING WINTER WX ADVISORIES GO WITH THE NORTHERN HALF
OF THE ADVISORY SECTION PROBABLY GETTING UP TO ANOTHER INCH
THROUGH 00Z...AND FRONTOGENESIS BAND OF SNOW JUST STARTING TO MAKE
IT ACRS THE SOUTHERN CWA AND THE SOUTHERN SECTION OF THE ADVISORY
WHICH GOES THROUGH 06Z TONIGHT. ALL IN ALL MOST SITES IN THE
ADVISORIES TO GET FROM 2-3 INCHES FROM 12Z THIS MORNING THOUGH
THIS EVENING...BUT BRISK NORTH TO NORTHEAST WINDS OF 10-20 MPH PRODUCING
DRIFTING OF POWDERY SNOW AND REDUCED VSBYS IN BOUTS OF HEAVIER
SNOW WITH FOG MAKING FOR HAZARDOUS TRAVEL SUPPORTING THE NEED OF
HEADLINES. PLUS STILL FEEL WITH UPTICK IN ELEVATED FRONTOGENETICAL
FORCING THIS EVENING...AREAS ALONG AND SOUTH OF A LINE FROM
FAIRFIELD IA TO NORTHEAST OF MONMOUTH WILL SEE AMOUNTS MORE IN THE
LINE OF 2-4 INCHES WITH SOME ISOLATED 5 INCH AMOUNTS POSSIBLE BY MIDNIGHT.
THEN AS NORTHEASTERLY SFC WINDS BACK TO THE NORTH...MORE OF A COLD
FETCH/CAA WILL OCCUR LATER TONIGHT AND MAKE FOR LOWS IN THE LOW
TO MID SINGLE DIGITS ABOVE ZERO EAST OF THE MS RVR INTO NORTHEASTERN
MO...AND SUBZERO LOWS GENERALLY ACRS THE NORTHWESTERN HALF OF THE
DVN CWA...-5 TO -10F IN DEEPER SNOWPACK AREAS AND RVR VALLEYS OF THE
NORTHWESTERN THIRD...AND WAPSI VALLEY TO THE MS RVR. COMBINED
WITH IN-BUILDING PRESSURE GRADIENT OFF NORTHERN PLAINS ARCTIC
RIDGE AND SUSTAINED 8-12 MPH WINDS...THESE TEMPS WILL PRODUCE WIND
CHILL ADVISORY CRITERIA FROM JUST AFTER MIDNIGHT THROUGH 11 AM CST OR
NOON THU FOR AREAS GENERALLY ALONG AND NORTHWEST OF A LINE FROM
STOCKTON IN FAR NW IL...TO TIPTON IA...AND TO FAIRFIELD IA. WILL
ISSUE THE WIND CHILL ADVISORY FOR THESE AREAS WITH THE POTENTIAL
TO EXPAND A TIER OF COUNTIES EASTWARD IF THE COLD SEEPAGE CREEPS
FURTHER TO THE EAST THAN CURRENTLY EXPECTED. CLOUDY TO MOSTLY
CLOUDY SKIES CONTINUE THROUGH TONIGHT,,,WITH THE POSSIBILITY OF
SOME NEWLY PRODUCED FLURRIES MOVING ACRS THE CWA FROM NORTH TO SOUTH
AFTER THE MAIN BAND OF SNOW SLIPS OFF TO THE SOUTHEAST.
ARCTIC HIGH BARRELS IT/S WAY ACRS IA INTO NORTHWESTERN IL AS DAY
PROGRESSES WITH ONGOING STOUT CAA. DESPITE THIS RIDGE CLEARING
THINGS OUT/EXCEPT MAYBE SOME BRIEF WDLY SCTRD INSTABILITY FLURRIES
OR SHOWERS/...TEMPS WILL HAVE A HARD TIME RECOVERING MUCH FROM
MORNING LOWS...SINGLE DIGITS ABOVE ZERO EXCEPT THE FAR EAST AND
SOUTHEAST WHICH MAY HIT +10 OR A FEW DEGREES WARMER. ..12..
.LONG TERM...(THURSDAY NIGHT THROUGH NEXT WEDNESDAY)
ISSUED AT 315 PM CST WED JAN 1 2014
THE MAIN FORECAST THIS PERIOD WILL BE TEMPERATURES THROUGH THE
PERIOD. MODELS ARE IN GOOD OVERALL AGREEMENT WITH THE LARGE SCALE
PATTERN BUT THERE IS SOME DISAGREEMENT IN THE TIMING AND PLACEMENT
OF FEATURES BY THIS WEEKEND.
THE CURRENT ACTIVE WEATHER REGIME IS FORECAST TO CONTINUE INTO AT
LEAST EARLY NEXT WEEK AS SEVERAL REINFORCING SHOTS OF COLD AIR DROP
INTO THE GREAT PLAINS. SHORTWAVE RIDGING WILL BUILD INTO THE REGION
BY THURSDAY NIGHT INTO FRIDAY MORNING WITH SKIES CLEARING
OVERNIGHT. 850 TEMPERATURES OF -15*C TO -20*C ACROSS THE REGION
WILL LEAD TO POTENTIAL NEAR RECORD LOWS ON FRIDAY MORNING. PLEASE
SEE THE CLIMATE SECTION BELOW.
HIGH PRESSURE WILL SHIFT EASTWARD ON FRIDAY MORNING ALLOWING FOR
WINDS TO VEER TO THE SOUTH AND BEGIN WARM ADVECTING INTO THE REGION ON
FRIDAY AND SATURDAY AHEAD OF THE NEXT ALBERTA CLIPPER. A TIGHTENING
PRESSURE GRADIENT ON FRIDAY WILL LEAD TO BREEZY CONDITIONS INTO
SATURDAY. SATURDAY WILL BE THE WARMEST DAY OF THE PERIOD WITH
TEMPERATURES CLOSER TO NORMALS IN THE UPPER 20S TO LOWER 30S.
CLOUDS WILL BEGIN OVERSPREADING THE REGION ON SATURDAY AHEAD OF A
CLIPPER THAT WILL DRAG A STRONG COLD FRONT ACROSS THE REGION
SATURDAY AFTERNOON INTO THE EVENING. THE BETTER DYNAMICS AND
MOISTURE WITH THIS SYSTEM WILL BE ALONG AND BEHIND THE FRONT. THE
GFS IS QUICKER WITH THE SYSTEM AND ENDS PRECIPITATION BY 06 UTC ON
SUNDAY WHILE THE ECMWF IS WETTER AND CONTINUES THE PRECIPITATION
THROUGH 18 UTC ON SUNDAY. HAVE A COMBINATION OF THE TWO SOLUTIONS
GOING INTO SUNDAY WITH SOME LINGERING SNOW THROUGH 18 UTC.
VERY STRONG COLD ADVECTION WILL BE ONGOING SUNDAY NIGHT INTO MONDAY
WITH A STRONG 1040 TO 1050 MB SURFACE HIGH BUILDING SOUTHEASTWARD
INTO MONTANA. THE GFS AND ECMWF SHOW THE SURFACE HIGH MODERATING TO
BETWEEN 1030 TO 1040 MB BY TUESDAY MORNING ACROSS IOWA. 850
TEMPERATURES WILL HAVE COOLED TO -20*C TO -30*C BY 12 UTC ON MONDAY
AND FURTHER COOLING TO -24*C TO -30*C BY 12 UTC ON TUESDAY. THESE
TEMPERATURES ARE 2 TO 3 STANDARD DEVIATIONS BELOW THE MEAN FOR
JANUARY SO THIS WILL BE AN UNUSUALLY COLD AIRMASS BUILDING INTO THE
REGION EARLY NEXT WEEK. SURFACE TEMPERATURES MAY REMAIN BELOW ZERO
SUNDAY NIGHT THROUGH TUESDAY. SOME OF THIS COLD AIR MAY BE HIGHLY
DEPENDENT ON THE SNOWPACK TO OUR NORTH. AFTER TUESDAY...HIGH
PRESSURE WILL SHIFT EASTWARD ALLOWING FOR A RETURN TO MORE MODERATE
AIR FOR THE MIDDLE OF NEXT WEEK. IN ADDITION TO THE COLD AIR THE
PRESSURE GRADIENT WILL BE TIGHT ACROSS THE REGION ON MONDAY SO
ANOTHER BREEZY OVERNIGHT WHICH WILL MAKE TEMPERATURES FEEL MUCH
COLDER THAN THE AIR. COUSINS
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1144 PM CST WED JAN 1 2014
MOIST NORTHERLY LOW LEVEL FLOW WILL BE VFR CIGS IN THE 4 TO 6KFT
RANGE INTO THURSDAY MORNING. THERE WILL BE SOME PATCHY MVFR CIGS
AROUND 2 KFT ESPECIALLY NEAR THE MISSISSIPPI RIVER OVER NIGHT.
VFR CONDITIONS ARE EXPECTED FOR MOST OF THURSDAY AFTERNOON AND
EVENING WITH CLEARING SKIES EXPECTED.
&&
.CLIMATE...
ISSUED AT 315 PM CST WED JAN 1 2014
RECORD LOWS FOR JANUARY 2...
MOLINE.........-27 IN 1979
CEDAR RAPIDS...-19 IN 1979
DUBUQUE........-22 IN 1879
BURLINGTON.....-15 IN 1979
RECORD LOWS FOR JANUARY 3...
MOLINE.........-16 IN 1887
CEDAR RAPIDS...-15 IN 1919
DUBUQUE........-24 IN 1887
BURLINGTON.....-16 IN 1919
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WIND CHILL ADVISORY UNTIL NOON CST THURSDAY FOR BENTON-BUCHANAN-
CEDAR-CLINTON-DELAWARE-DUBUQUE-IOWA-JACKSON-JEFFERSON-
JOHNSON-JONES-KEOKUK-LINN-WASHINGTON.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR LEE.
IL...WIND CHILL ADVISORY UNTIL NOON CST THURSDAY FOR JO DAVIESS.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR HANCOCK-
MCDONOUGH.
MO...NONE.
&&
$$
UPDATE...DLF
SHORT TERM...12
LONG TERM...COUSINS
AVIATION...DLF
CLIMATE...COUSINS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
310 PM EST THU JAN 2 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 310 PM EST THU JAN 2 2014
19Z SFC ANALYSIS SHOWS THE NOW DEEPER LOW JUST EAST OF KENTUCKY WITH
THE TIGHT ISOBARS CROSSING INTO EAST KENTUCKY. THIS IS RESULTING IN
STIFF NORTHWEST WINDS WITH GUSTS TO 30 MPH BRINGING IN THE MUCH
COLDER AIR. RAIN HAS CHANGED TO SNOW ACROSS WESTERN PARTS OF THE
AREA AND NOW HERE AT JKL. ANOTHER HOUR OR SO IT WILL BE SNOW
EVERYWHERE...IN PLACES THAT STILL ARE PRECIPITATING. THERE IS
CURRENTLY A DISTINCT BACK EDGE TO THIS POST FRONTAL SNOW AREA.
HOWEVER...ANOTHER DECENT BATCH OF SNOW IS DROPPING THROUGH SOUTHERN
INDIANA ON RADAR AND THIS SHOULD MOVE OVER OUR CWA THIS EVENING.
TEMPERATURES CURRENTLY VARY FROM THE LOW 40S NEAR MIDDLESBORO TO
AROUND FREEZING OVER OUR WESTERN COUNTIES. DEWPOINTS ARE PEGGED TO
THE TEMPERATURE IN MOST SPOTS WITH THE GUSTY NORTHWEST WINDS NOW
REPORTED AT MOST OBS SITES IN THE AREA.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE SHARP AND DEEP TROUGH
CURRENTLY SWINGING THROUGH THE AREA. HEIGHTS WILL THEN QUICKLY CLIMB
LATE TONIGHT INTO FRIDAY IN THE WAKE OF THE DEPARTING WAVE. FAST...
MOSTLY ZONAL...FLOW FOLLOWS INTO SATURDAY MORNING WITH ONLY VERY
MINOR BITS OF ENERGY FLOATING BY IN THE AIR STREAM AT MID LEVELS.
WITH NO GREAT DISTINCTION IN THE MODELS HAVE FAVORED A BLEND WITH A
LEAN TOWARD THE HRRR AND NAM12 FOR NEAR TERM SPECIFICS.
SENSIBLE WEATHER WILL FEATURE A BAND OF SNOW MOVING THROUGH EAST
KENTUCKY ASSOCIATED WITH THE RETURN OF AN ARCTIC AIR MASS. SOME
PLACES...PARTICULARLY IN THE SOUTHWEST...WILL SEE A LULL IN THE SNOW
FOR SEVERAL HOURS INTO THE EVENING WITH A POSSIBLE RESURGENCE AROUND
00Z AS THAT SNOW OVER INDIANA MOVES INTO OUR CWA. EVEN IN THOSE
PLACES...HAZARDOUS CONDITIONS WILL EXIST AS WET ROADS A THREAT TO
ICE OVER SINCE THE ARCTIC AIR QUICKLY DROPS TEMPERATURES INTO THE 20S
FROM WEST TO EAST LATE THIS AFTERNOON AND EARLY EVENING.
ACCORDINGLY...WILL MAINTAIN THE CURRENT ADVISORY STRUCTURE AND FOCUS
ON THE REFREEZE FOR WESTERN MOST PLACES THAT WILL NOT GET MUCH OF THE
UPSLOPE. OTHERWISE...UPSLOPE SNOW SHOWERS/ SQUALLS...COLD TEMPS...
AND LOSS OF SOLAR INSOLATION SHOULD HELP THE EASTERN PORTION OF THE
ADVISORIES PICK UP SNOW TOTALS THROUGH THE EVENING. THE SNOWS WILL
TAPER OFF FROM WEST TO EAST LATER TONIGHT...ENDING LAST IN LOCATIONS
NEAR THE VIRGINIA AND WEST VIRGINIA BORDERS TOWARD DAWN. BY THAT TIME
READINGS WILL BE DOWN IN THE TEENS FOR MOST LOCATIONS WITH SOME
SINGLE DIGITS POSSIBLE IN THE FAR NORTHWESTERN PARTS OF THE CWA.
WINDS RUNNING IN THE 5 TO 10 MPH RANGE INTO EARLY FRIDAY MORNING
WILL YIELD WIND CHILLS IN MANY SPOTS DOWN NEAR ZERO. THE QUICK EXIT
OF THE WEATHER MAKER WILL RETURN SUNNY SKIES TO THE AREA ON FRIDAY...
BUT CAA AND THE ARCTIC AIR IN PLACE WILL KEEP TEMPERATURES FROM
GETTING ANY HIGHER THAN THE LOW TO MID 20S. THIS WILL SET THE STAGE
FOR ANOTHER BITTERLY COLD NIGHT WITH READINGS FALLING INTO THE TEENS
AGAIN ALONG WITH NOTICEABLE RIDGE AND VALLEY DIFFERENCES.
AGAIN LEANED ON THE SOLID CONSSHORT OR BC VERSION FOR HOURLY TEMPS...
DEWS...AND WINDS THROUGH 12Z FRIDAY WITH CONSALL AFTER THAT. AS FOR
POPS...WENT HIGHER THAN GUIDANCE TONIGHT DUE TO IT NOT PICKING UP ON
UPSLOPE SNOWS VERY WELL...DRY AFTER THAT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 250 PM EST THU JAN 2 2014
PRETTY GOOD AGREEMENT AMONGST THE MODELS FOR THE EXTENDED PERIOD.
THE ECMWF MODEL IS A BIT MORE ROBUST WITH ITS QPF THAN THE GFS FOR
THE SUNDAY NIGHT THROUGH MONDAY NIGHT WEATHER SYSTEM...AND THE
WEATHER SYSTEM FOR THE END OF THE WEEK. HOWEVER...THE OVERALL LARGE
SCALE WEATHER PATTERN...BOTH ALOFT AND AT THE SURFACE...IS SIMILAR
IN BOTH MODELS. THAT BEING SAID...WENT MORE TOWARD THE ECMWF
SOLUTION THIS TIME AROUND. TOOK DOWN SNOWFALL TOTALS
SLIGHTLY...HOWEVER...AS THE MODELS HAVE MORE WESTERLY...AS OPPOSED
TO NORTHWESTERLY...FLOW FORECAST...WHICH WOULD BE MUCH LESS
FAVORABLE FOR UPSLOPE SNOW SHOWERS. THE DYNAMICS WITH THE SYSTEM TO
BEGIN THE WEEK ARE STILL EXPECTED TO BE QUITE STRONG...WITH A WELL
DEVELOPED AREA OF LOW PRESSURE MOVING OUT OF THE MID MISSISSIPPI
VALLEY THROUGH THE OHIO VALLEY AND THEN INTO THE EASTERN GREAT LAKES
REGION. A 50 TO 60KT LOW LEVEL JET WOULD BRING AMPLE GULF MOISTURE
INTO THE REGION ALOFT TO AID IN ICE CRYSTAL AND THEREFORE SNOWFLAKE
FORMATION SUNDAY NIGHT AND MONDAY. SNOWFALL TOTALS...DUE TO THE GOOD
DYNAMICS...COULD STILL RANGE BETWEEN 2 AND 3 INCHES FOR MOST OF THE
AREA DURING THE INITIAL EVENT. BITTERLY COLD ARCTIC AIR WILL SPILL
INTO THE AREA TO BEING THE WEEK. THE COLDEST NIGHT OF THE UPCOMING
WORK WEEK LOOKS TO BE MONDAY NIGHT...WHEN LOWS COULD CONCEIVABLE
DROP TO ZERO OR BELOW ZERO FOR THE ENTIRE AREA. WITH THE MODEL
SOUNDINGS DEPICTING 850 HPA TEMPERATURES IN THE MINUS 24 TO MINUS 30
RANGE...SUBZERO LOWS MONDAY NIGHT WOULD NOT BE ALL THAT SURPRISING.
THE COLD AIR MASS WILL MODIFY ONLY SLIGHT TUESDAY WITH HIGHS PEAKING
IN THE TEENS FOR MOST OF THE AREA...WITH HIGHS BARELY TOPPING OUT
AROUND 10 DEGREES NORTH OF I-64. LOWS IN THE SINGLE DIGITS ARE
LIKELY TUESDAY NIGHT...AS WINDS GO NEARLY CALM BENEATH PARTLY CLOUDY
SKIES. HIGHS AND LOWS WEDNESDAY THROUGH THURSDAY WILL BE WELL BELOW
AS WELL...AS THE COLD AIR MASS MAINTAINS ITS GRIP ON THE AREA. A
SECOND WEATHER SYSTEM IS THEN PROGGED TO MOVE ACROSS THE TENNESSEE
AND OHIO VALLEY REGIONS TO END THE WEEK...WITH MORE POTENTIAL FOR
ACCUMULATING SNOW WEDNESDAY NIGHT INTO EARLY THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1245 PM EST THU JAN 2 2014
CEILINGS WILL BE RATHER LOW...DOWN TO LIFR AT TIMES...THROUGH THE
REST OF THE AFTERNOON AND EVENING AS RAIN AND DRIZZLE TRANSITIONS TO
SNOW. WINDS WILL INCREASE TO BETWEEN 10 TO 15 KTS WITH GUSTS OVER 20
KTS AS THEY SWITCH TO THE NORTHWEST BY MID AFTERNOON. EXPECT GRADUAL
IMPROVEMENTS TO CIGS AND VIS FOR THE LATTER PART OF THE TAF PERIOD
WHILE THE WINDS ALSO SETTLE TO BETWEEN 5 AND 10 KTS FROM THE
NORTHWEST FOR THE FIRST PART OF FRIDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR KYZ052-
058>060-104-106-108.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR KYZ044-
050-051-068-069-079-080-083-084.
WINTER WEATHER ADVISORY UNTIL 8 AM EST FRIDAY FOR KYZ088-118-120.
WINTER WEATHER ADVISORY UNTIL 6 AM EST FRIDAY FOR KYZ085>087-107-
109>117-119.
&&
$$
SHORT TERM...GREIF
LONG TERM...AR
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS PADUCAH KY
204 PM CST Thu Jan 2 2014
.SHORT TERM /TODAY THROUGH SATURDAY/...
ISSUED AT 350 AM CST THU JAN 2 2014
In the near term...the minor snow event appears to be on track to
occur in the next several hours. The rain/snow line was located
roughly from Mt. Carmel to Marion IL...southwest to Poplar Bluff
MO at 09z. This transition line will move southeast across all but
the khop area by around 13z. Radar indicates a swath of steady
snow /20 to 25 dbz echoes/ from just se of kstl to kuno as of 09z.
Based on HRRR simulated reflectivity and RAP 1000/500 mb mean
rh fields...this area of steadier snow is likely to lift
east/northeast across the existing winter weather advisory area
this morning. Forecast snowfall amounts appear on track...though
they have been tweaked slightly downward in some areas. Any two
inch amounts would be rather isolated.
Forecast model soundings indicate a very well mixed boundary layer
this afternoon as the arctic air mass settles in. This may
translate to considerable cold air stratocu and flurries. Gusty
winds are also anticipated...with bufkit momentum transfer
algorithm suggesting gusts around 30 mph. Guidance is in
agreement that temperatures will remain steady in the 20s this
afternoon.
The remainder of the forecast is dry...so the main issue is temps.
A 1035 mb surface high will be centered almost directly over the
kstl area at 12z Friday. With clear skies and light
winds...conditions would suggest low temps near zero over snow
cover. The main concern is where the significant snow cover will
exist. Will tweak lows further downward over anticipated snow
cover along and northwest of a line from kmdh to the Wabash
Valley. Elsewhere...model guidance appears reasonable.
Southerly return flow will develop on the back side of the high
Friday. Due to the cold start to the day...highs will still not
reach freezing despite abundant sunshine. Increasing southwest
low level flow Friday night and Saturday will eventually bring
temps close to climo ahead of the next arctic front.
.LONG TERM...(Saturday Night through Thursday)
ISSUED AT 150 PM CST THU JAN 2 2014
The long term event begins Saturday night. This is packing the
potential to be a major hazardous weather event for our region. It
is a near certainty that brutal arctic cold not seen since the mid
90s will hit the region for Monday and Tuesday. We see single
digit to teens for Highs, and near zero or even negative digits
for Lows. With a little wind, chills bottom out at -10 to -20 late
Monday night and Tuesday. Looking at Local Storm Reports for the
last such event, we highlighted the impacts from said event in a
headlined Special Weather Statement, and hit hard in social media,
to get the word out early on this coming impact of brutal arctic cold.
The precip with the event may also be signficant, if but for parts
of the area. Factors in favor of a signficant impact event include
the new model solutions for a closed surface low passing near or
just south/east of the FA. Some of the modeling includes a 925 mb
and/or 850 mb low passing along a similar track, and this would
enhance the potential for heavy snow bands. Excellent thermo-
dynamics exist for a potential heavy snow or embedded snow bands
within a 6 to 9 hour time frame from late Saturday night into
Sunday. It is still a tad too far out in time to pinpoint, but
preliminary estimated totals via allblend qpf amounts suggest
generally a range from trace/inch or less along our southern
border, to about an inch or two across the heart of the FA, to
potentially warning criteria across our north. This will be
monitored closely over the next 24 hours in case a headline
becomes warranted.
After the brutal early week cold, we do remain below freezing
through the mid week, then have a chance at moderating back to
above the freezing mark by the end of the week. However, snow
cover could impact this negatively, and another system is shaping
up for the days 7-8 time frame that may negate it as well.
&&
.AVIATION...
ISSUED AT 150 PM CST THU JAN 2 2014
MVFR cigs continue in bands, most dense east (KEVV/KOWB) to
scattering west (KCGI). This trend will continue thru the pm
hours, then we should start to see some improvement in overall sky
condition through the overnight hours. Anticipate a return to VFR
by the planning period as we transition to a more tranquil pattern
for the ensuing 24-48 hours.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PADUCAH KY
532 AM CST Thu Jan 2 2014
.UPDATE...
UPDATED AVIATION SECTION FOR 12Z TAFS
&&
.SHORT TERM /TODAY THROUGH SATURDAY/...
ISSUED AT 350 AM CST THU JAN 2 2014
In the near term...the minor snow event appears to be on track to
occur in the next several hours. The rain/snow line was located
roughly from Mt. Carmel to Marion IL...southwest to Poplar Bluff
MO at 09z. This transition line will move southeast across all but
the khop area by around 13z. Radar indicates a swath of steady
snow /20 to 25 dbz echoes/ from just se of kstl to kuno as of 09z.
Based on HRRR simulated reflectivity and RAP 1000/500 mb mean
rh fields...this area of steadier snow is likely to lift
east/northeast across the existing winter weather advisory area
this morning. Forecast snowfall amounts appear on track...though
they have been tweaked slightly downward in some areas. Any two
inch amounts would be rather isolated.
Forecast model soundings indicate a very well mixed boundary layer
this afternoon as the arctic air mass settles in. This may
translate to considerable cold air stratocu and flurries. Gusty
winds are also anticipated...with bufkit momentum transfer
algorithm suggesting gusts around 30 mph. Guidance is in
agreement that temperatures will remain steady in the 20s this
afternoon.
The remainder of the forecast is dry...so the main issue is temps.
A 1035 mb surface high will be centered almost directly over the
kstl area at 12z Friday. With clear skies and light
winds...conditions would suggest low temps near zero over snow
cover. The main concern is where the significant snow cover will
exist. Will tweak lows further downward over anticipated snow
cover along and northwest of a line from kmdh to the Wabash
Valley. Elsewhere...model guidance appears reasonable.
Southerly return flow will develop on the back side of the high
Friday. Due to the cold start to the day...highs will still not
reach freezing despite abundant sunshine. Increasing southwest
low level flow Friday night and Saturday will eventually bring
temps close to climo ahead of the next arctic front.
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 350 AM CST THU JAN 2 2014
The good news is that the medium range models are in very good
agreement throughout this extended forecast period. The bad news is
that they are advertising what could be a significant winter storm
over much of the area Saturday night and Sunday, followed by an
Arctic outbreak of an insane magnitude. Much of the area could see
some of the coldest air ever recorded, and that includes Evansville
with its longer period of record.
By 12Z Monday morning, the 00Z ECWMF and GFS have a 4950M 500mb low
near the east side of Lake Superior with an intense trough running
from the east slope of the Rockies through the northern Gulf Coast
States and then up the entire east coast. This will bring 850mb
temperatures in the -20F to -30F range to our region, which will
likely lead to surface temperatures that do not climb above zero in
the north Monday. The coldest high temperature ever recorded for any
day at Evansville has been -3F, so all time records will be in
jeopardy. The other concern is that winds will not be light, so wind
chills will be -10F to -20F for portions if not all of the area
Sunday night into Tuesday.
As the flow aloft begins to amplify, the models bring a lead
short-wave trough eastward through the area with a significant
surface system Saturday night through Sunday. QPF with this system
is near three quarters of an inch, and portions of southeast
Missouri, southern Illinois and possibly southwest Indiana may see
most of that as snow. Of course it will depend on the location, and
movement of the surface freezing line, which the ECMWF and GEM try
to hold up over west Kentucky and southwest Indiana well into
Sunday. The GFS is a bit faster with the entire system, and is most
agressive with the cold air. The potential exists for significant
accumulations of snow over much of the area. And with the Arctic
surge occurring late Sunday and Sunday night, any ice or snow will
be difficult to remove.
The combination of the initial winter storm and the eventual Arctic
airmass could snarl the region for much of next week. Will not issue
a Special Weather Statement for this extreme winter weather outbreak
at this time due to the ongoing Winter Weather Advisory event.
However, would expect one from the day shift after this morning`s
system has passed.
Some moderation will occur heading into Wednesday of next week,
according to the GFS and ECMWF, but warm advection on the back side
of the departing Arctic surface high will result in a good chance of
wintry precipitation. Added small pops for most of the area
Wednesday, and good chances for Wednesday night. This will be more
of a warm frontal evolution with snow becoming sleet and then
possibly rain/freezing rain through the event. For now just kept it
as a snow/sleet mix given the extremely cold airmass the system will
have to erode. The models keep southwest flow aloft through the end
of the week and there does not seem to be any fresh cold airmass to
move into the region, so the cold spell should be over by the end of
next week.
&&
.AVIATION...
ISSUED AT 532 AM CST THU JAN 2 2014
Strong cold front roughly along a KOWB to KCEY /Murray KY/ line at
11z will sweep southeast...quickly followed by northwest winds
gusting to 30 knots. An area of snow behind the front contains a
narrow band of ifr vsbys from KPAH to the Wabash Valley. There are
also ifr cigs along and immediately behind the front. By late this
morning...mvfr cigs are anticipated at all sites. There may be some
lingering patches of mvfr vsbys as late as 18z in KEVV/KOWB
areas...then vfr vsbys are expected at all sites for the remainder
of the taf period. Clearing skies and diminishing winds are expected
by 06z tonight as high pressure builds into the Mississippi Valley.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
KY...WINTER WEATHER ADVISORY until Noon CST today FOR KYZ014-018-019.
MO...WINTER WEATHER ADVISORY until 8 AM CST this morning FOR MOZ076.
IL...WINTER WEATHER ADVISORY until 8 AM CST this morning FOR ILZ075-
076-080>087.
WINTER WEATHER ADVISORY until Noon CST today FOR ILZ077-078.
IN...WINTER WEATHER ADVISORY until Noon CST today FOR INZ081-082-
085>088.
&&
$$
SHORT TERM...MY
LONG TERM....DRS
AVIATION...MY
AREA FORECAST DISCUSSION
NWS PADUCAH KY
350 AM CST Thu Jan 2 2014
.SHORT TERM /TODAY THROUGH SATURDAY/...
ISSUED AT 350 AM CST THU JAN 2 2014
In the near term...the minor snow event appears to be on track to
occur in the next several hours. The rain/snow line was located
roughly from Mt. Carmel to Marion IL...southwest to Poplar Bluff
MO at 09z. This transition line will move southeast across all but
the khop area by around 13z. Radar indicates a swath of steady
snow /20 to 25 dbz echoes/ from just se of kstl to kuno as of 09z.
Based on HRRR simulated reflectivity and RAP 1000/500 mb mean
rh fields...this area of steadier snow is likely to lift
east/northeast across the existing winter weather advisory area
this morning. Forecast snowfall amounts appear on track...though
they have been tweaked slightly downward in some areas. Any two
inch amounts would be rather isolated.
Forecast model soundings indicate a very well mixed boundary layer
this afternoon as the arctic air mass settles in. This may
translate to considerable cold air stratocu and flurries. Gusty
winds are also anticipated...with bufkit momentum transfer
algorithm suggesting gusts around 30 mph. Guidance is in
agreement that temperatures will remain steady in the 20s this
afternoon.
The remainder of the forecast is dry...so the main issue is temps.
A 1035 mb surface high will be centered almost directly over the
kstl area at 12z Friday. With clear skies and light
winds...conditions would suggest low temps near zero over snow
cover. The main concern is where the significant snow cover will
exist. Will tweak lows further downward over anticipated snow
cover along and northwest of a line from kmdh to the Wabash
Valley. Elsewhere...model guidance appears reasonable.
Southerly return flow will develop on the back side of the high
Friday. Due to the cold start to the day...highs will still not
reach freezing despite abundant sunshine. Increasing southwest
low level flow Friday night and Saturday will eventually bring
temps close to climo ahead of the next arctic front.
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 350 AM CST THU JAN 2 2014
The good news is that the medium range models are in very good
agreement throughout this extended forecast period. The bad news is
that they are advertising what could be a significant winter storm
over much of the area Saturday night and Sunday, followed by an
Arctic outbreak of an insane magnitude. Much of the area could see
some of the coldest air ever recorded, and that includes Evansville
with its longer period of record.
By 12Z Monday morning, the 00Z ECWMF and GFS have a 4950M 500mb low
near the east side of Lake Superior with an intense trough running
from the east slope of the Rockies through the northern Gulf Coast
States and then up the entire east coast. This will bring 850mb
temperatures in the -20F to -30F range to our region, which will
likely lead to surface temperatures that do not climb above zero in
the north Monday. The coldest high temperature ever recorded for any
day at Evansville has been -3F, so all time records will be in
jeopardy. The other concern is that winds will not be light, so wind
chills will be -10F to -20F for portions if not all of the area
Sunday night into Tuesday.
As the flow aloft begins to amplify, the models bring a lead
short-wave trough eastward through the area with a significant
surface system Saturday night through Sunday. QPF with this system
is near three quarters of an inch, and portions of southeast
Missouri, southern Illinois and possibly southwest Indiana may see
most of that as snow. Of course it will depend on the location, and
movement of the surface freezing line, which the ECMWF and GEM try
to hold up over west Kentucky and southwest Indiana well into
Sunday. The GFS is a bit faster with the entire system, and is most
agressive with the cold air. The potential exists for significant
accumulations of snow over much of the area. And with the Arctic
surge occurring late Sunday and Sunday night, any ice or snow will
be difficult to remove.
The combination of the initial winter storm and the eventual Arctic
airmass could snarl the region for much of next week. Will not issue
a Special Weather Statement for this extreme winter weather outbreak
at this time due to the ongoing Winter Weather Advisory event.
However, would expect one from the day shift after this morning`s
system has passed.
Some moderation will occur heading into Wednesday of next week,
according to the GFS and ECMWF, but warm advection on the back side
of the departing Arctic surface high will result in a good chance of
wintry precipitation. Added small pops for most of the area
Wednesday, and good chances for Wednesday night. This will be more
of a warm frontal evolution with snow becoming sleet and then
possibly rain/freezing rain through the event. For now just kept it
as a snow/sleet mix given the extremely cold airmass the system will
have to erode. The models keep southwest flow aloft through the end
of the week and there does not seem to be any fresh cold airmass to
move into the region, so the cold spell should be over by the end of
next week.
&&
.AVIATION...
ISSUED AT 350 AM CST THU JAN 2 2014
Strong cold front roughly along a KEVV to KPAH line at 09z will
sweep southeast...quickly followed by northwest winds gusting to
30 knots. Areas of ifr cigs behind the front appear rather
localized and should not persist more than a couple hours. By
late this morning...mvfr cigs are anticipated at all sites. A
period of snow early this morning will result in mvfr vsbys for a
few hours...with some brief ifr vsbys possible in kevv/kowb area.
Otherwise...vfr vsbys are expected through the period. Clearing
skies and diminishing winds are expected tonight as high pressure
builds into the Mississippi Valley.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
KY...WINTER WEATHER ADVISORY until Noon CST today FOR KYZ014-018-019.
MO...WINTER WEATHER ADVISORY until 8 AM CST this morning FOR MOZ076.
IL...WINTER WEATHER ADVISORY until 8 AM CST this morning FOR ILZ075-
076-080>087.
WINTER WEATHER ADVISORY until Noon CST today FOR ILZ077-078.
IN...WINTER WEATHER ADVISORY until Noon CST today FOR INZ081-082-
085>088.
&&
$$
SHORT TERM...MY
LONG TERM....DRS
AVIATION...MY
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
421 PM EST THU JAN 2 2014
LATEST UPDATE...
MARINE
.SYNOPSIS...
ISSUED AT 236 PM EST THU JAN 2 2014
THE BIG WEATHER STORY IS THE COLD OUTBREAK EXPECTED EARLY NEXT WEEK.
HIGHS IN THE SINGLE DIGITS AND LOWS IN THE 0 TO 10 BELOW RANGE ARE
EXPECTED. WIND CHILLS COULD DROP AS LOW AS 25 BELOW ON MONDAY AND
TUESDAY. WIND GUSTS ARE FORECAST TO BE AROUND 20 TO 30 MPH.
ANOTHER VERY COLD NIGHT IS IN STORE TONIGHT WITH LOWS IN THE 0 TO
5 BELOW RANGE. SOME LIGHT SNOW NEAR THE LAKESHORE IS POSSIBLE
FRIDAY. WIDESPREAD HEAVIER SNOW WILL MOVE IN SUNDAY AND SUNDAY
NIGHT. SIGNIFICANT ACCUMULATIONS APPEAR LIKELY AT THIS
TIME...ESPECIALLY SOUTH AND EAST OF GRAND RAPIDS.
TEMPERATURES WILL MODERATE CONSIDERABLY ON SATURDAY BEFORE THE
ARCTIC AIR PLUNGES BACK IN. HIGHS ON SATURDAY WILL BE NEAR 30
DEGREES.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 303 PM EST THU JAN 2 2014
MAIN CHALLENGE IN THE VERY SHORT TERM IS ASSESSING SNOW POTENTIAL
NEAR THE LAKESHORE...PARTICULARLY AROUND THE SABLE POINTS OF MASON
AND OCEANA COUNTIES. A DOMINANT LAKE SNOW BAND NEAR THE WESTERN LAKE
MICHIGAN SHORELINE THIS MORNING IS SLOWLY DRIFTING EAST. THE LAST
SEVERAL HRRR MODEL RUNS...AS WELL AS THE NAM...APPEAR TO BE PLACING
OR MOVING THIS FEATURE TOO FAR EAST TOWARDS THE POINTS.
IT IS LOOKING MORE LIKELY THAT WE WILL CLEAR OUT OVER INLAND ZONES
TONIGHT...ALLOWING FOR VERY COLD INLAND TEMPERATURES FRIDAY MORNING
AND A LAND BREEZE THAT HAS A GOOD CHANCE OF KEEPING THE SNOW BAND
OFFSHORE. DISCUSSED THIS WITH THE GAYLORD OFFICE AND WE BOTH CONCUR
THAT THIS IS THE MOST LIKELY SCENARIO AT THIS POINT. HAVE THEREFORE
TRIMMED POPS AND ACCUMULATIONS EXCEPT FOR THE IMMEDIATE COAST.
STILL LOOKING FAVORABLE FOR LIGHT LAKE ENHANCED SNOW FRIDAY AHEAD OF
THE NEXT CLIPPER. DID NOT CHANGE THE INHERITED FORECAST
SIGNIFICANTLY. FROM FRIDAY NIGHT THROUGH SATURDAY POPS INCREASE FROM
NORTHWEST TO SOUTHEAST AHEAD OF THE CLIPPER AND ASSOCIATED COLD
FRONT WHICH SHOULD BE ENTERING THE FORECAST AREA BY SATURDAY EVENING.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 328 PM EST THU JAN 2 2014
THE MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT ON THE LARGE
SCALE FLOW WITH MINOR DIFFERENCES IN THE SMALLER SCALE FEATURES.
CONFIDENCE IS HIGH DUE TO CONTINUITY IN TIME AND SPACE. WIND CHILL
VALUES AND SNOWFALL ARE THE CHALLENGES WITH THIS FORECAST PACKAGE.
TEMPERATURES WILL FALL TO 0-5 DEGREES SUNDAY NIGHT AND ON MONDAY THE
HIGHS WILL BE AROUND 5 DEGREES ABOVE ZERO. THE LOWS MONDAY NIGHT
WILL BE BELOW ZERO. VALUES THIS LOW HAVE NOT BEEN SEEN IN THIS AREA
SINCE FEB 2007. THE TEMPERATURES WILL BEGIN TO RECOVER WEDNESDAY.
ALONG WITH THE COLD AIR... STRONG GUSTY WINDS OUT OF THE WEST AND
NORTHWEST WILL PRODUCE LOW WIND CHILL VALUES. THE COLDEST WIND
CHILLS... BETWEEN 20 AND 30 DEGREES BELOW ZERO ARE POSSIBLE MONDAY
EVENING INTO TUESDAY MORNING. A WIND CHILL ADVISORY AND MAYBE A WIND
CHILL WARNING WILL BE NEEDED MONDAY AFTERNOON THROUGH TUESDAY
AFTERNOON.
THIS ALSO SEEMS TO BE A SNOWY PERIOD OF TIME. AN UPPER LOW WILL DROP
SOUTH FROM NEAR THE POLE AND MOVE EAST ACROSS SOTHERN CANADA THROUGH
THE LONG TERM. THIS AND SHORTWAVES MOVING THROUGH THE FLOW AROUND
THE LOW WILL BRING THE COLD AIR... CYCLONIC FLOW AND SNOW. A FEW
SHORTWAVES SHOULD PASS CLOSE ENOUGH TO THE AREA TO RESULT IN SNOW
SATURDAY NIGHT THROUGH SUNDAY NIGHT. THE UPPER LOW WILL HELP TO BUMP
UP THE LAKE EFFECT SNOW MONDAY INTO WEDNESDAY AS THE SYSTEM PULLS
AWAY. WITH THE COLD TEMPERATURES... THE LAKE EFFECT SNOW IS EXPECTED
TO BE IN THE FORM OF SMALL ICE CRYSTALS. THEREFORE THE SNOW WILL NOT
STACK UP... BUT THE STRONG WINDS WILL BLOW THIS SNOW AROUND. THIS
WILL RESULT IN GREATLY REDUCED VISIBILITIES. THIS WILL ESPECIALLY BE
TRUE NEAR LAKE MICHIGAN.
A MORE ZONAL FLOW PATTERN WILL ENSUE WEDNESDAY... AS A LOW PRESSURE
SYSTEM BEGINS MOVING BY TO THE SOUTH OF THE REGION. THIS HAS THE
POTENTIAL FOR ADDITIONAL SNOWFALL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1254 PM EST THU JAN 2 2014
THE BAND OF SNOW IS FINALLY DIMINISHING AND PULLING OUT OF THE
FORECAST AREA. IFR VISIBILITIES CONTINUE FOR THE SOUTHERN TAF SITES
AND LANSING. RADAR INDICATES LANSING SHOULD BE CLEAR OF THE BAND IN
AN HOUR... WITH KALAMAZOO AND BATTLE CREEK IMPROVING IN ONE TO TWO
HOURS. JACKSON SHOULD CONTINUE IN THE SNOW FOR MAYBE THREE HOURS.
MVFR/VFR CEILINGS WILL IMPROVE TO VFR TONIGHT. THERE IS A CHANCE OF
SOME LAKE EFFECT SNOW MOVING OVER MUSKEGON EARLY FRIDAY WITH MVFR
CONDITIONS POSSIBLE.
WINDS OUT OF THE NORTH AND NORTHEAST AT 10 TO 15 KNOTS WITH GUSTS TO
20 KNOTS WILL FALL TO UNDER 10 KNOTS TONIGHT.
&&
.MARINE...
ISSUED AT 421 PM EST THU JAN 2 2014
THERE MAY BE A BRIEF LULL IN WAVES OVERNIGHT IN SPOTS DUE TO
LIGHT WINDS IN THE VICINITY OF A SNOW BAND THAT SHOULD PERSIST
JUST OFF THE COAST. WINDS AND WAVES WILL INCREASE TO SOLID SMALL
CRAFT CRITERIA DURING FRIDAY WITH GALES POSSIBLE BEGINNING LATE IN
THE DAY.
&&
.HYDROLOGY...
ISSUED AT 236 PM EST THU JAN 2 2014
A FLOOD ADVISORY IS IN EFFECT FOR THE FLAT RIVER AT SMYRNA. A
SUSPECTED ICE JAM UPSTREAM IS CAUSING A SHARP RISE AT THE SMYRNA
RIVER GAUGE. THE ICE JAM ON THE MUSKEGON RIVER THAT HAS IMPACTED
EVART SEEMS TO HAVE STABILIZED. THE MUSKEGON RIVER AT EVART IS NOW
ON A GRADUAL DECLINE. THE FLOOD ADVISORIES FOR THE MUSKEGON RIVER AT
EVART AND THE PERE MARQUETTE RIVER AT SCOTTVILLE HAVE BEEN CANCELED.
RIVERS WILL CONTINUE GAINING ICE COVERAGE AND THICKNESS FOR THE
FORESEEABLE FUTURE. THOSE RIVERS THAT ICE OVER COMPLETELY WILL HAVE
A MINIMAL ICE JAM THREAT. RIVERS WITH JAGGED ICE BUILDUP ARE IN
DANGER OF EXPERIENCING JAMMING AND RAPID FLUCTUATIONS. WIDESPREAD
HEAVIER SNOW IS LIKELY SUNDAY AND SUNDAY NIGHT...FOLLOWED
IMMEDIATELY BY A BLAST OF EXTREMELY COLD AIR. HOPEFULLY RIVER LEVELS
WILL LOCK IN SOMEWHAT WITH THE COLD AIR IN PLACE.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...GALE WATCH FROM FRIDAY EVENING THROUGH SATURDAY AFTERNOON FOR
LMZ844>849.
SMALL CRAFT ADVISORY UNTIL 1 PM EST FRIDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...EBW
SHORT TERM...TJT
LONG TERM...63
AVIATION...63
HYDROLOGY...EBW
MARINE...TJT
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
329 PM EST THU JAN 2 2014
LATEST UPDATE...
LONG TERM
.SYNOPSIS...
ISSUED AT 236 PM EST THU JAN 2 2014
THE BIG WEATHER STORY IS THE COLD OUTBREAK EXPECTED EARLY NEXT WEEK.
HIGHS IN THE SINGLE DIGITS AND LOWS IN THE 0 TO 10 BELOW RANGE ARE
EXPECTED. WIND CHILLS COULD DROP AS LOW AS 25 BELOW ON MONDAY AND
TUESDAY. WIND GUSTS ARE FORECAST TO BE AROUND 20 TO 30 MPH.
ANOTHER VERY COLD NIGHT IS IN STORE WITH LOWS IN THE 0 TO 5 BELOW
RANGE. SOME LIGHT SNOW NEAR THE LAKESHORE IS POSSIBLE FRIDAY.
WIDESPREAD HEAVIER SNOW WILL MOVE IN SUNDAY AND SUNDAY NIGHT.
SIGNIFICANT ACCUMULATIONS APPEAR LIKELY AT THIS TIME...ESPECIALLY
SOUTH AND EAST OF GRAND RAPIDS.
TEMPERATURES WILL MODERATE CONSIDERABLY ON SATURDAY BEFORE THE
ARCTIC AIR PLUNGES BACK IN. HIGHS ON SATURDAY WILL BE NEAR 30
DEGREES.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 303 PM EST THU JAN 2 2014
MAIN CHALLENGE IN THE VERY SHORT TERM IS ASSESSING SNOW POTENTIAL
NEAR THE LAKESHORE...PARTICULARLY AROUND THE SABLE POINTS OF MASON
AND OCEANA COUNTIES. A DOMINANT LAKE SNOW BAND NEAR THE WESTERN LAKE
MICHIGAN SHORELINE THIS MORNING IS SLOWLY DRIFTING EAST. THE LAST
SEVERAL HRRR MODEL RUNS...AS WELL AS THE NAM...APPEAR TO BE PLACING
OR MOVING THIS FEATURE TOO FAR EAST TOWARDS THE POINTS.
IT IS LOOKING MORE LIKELY THAT WE WILL CLEAR OUT OVER INLAND ZONES
TONIGHT...ALLOWING FOR VERY COLD INLAND TEMPERATURES FRIDAY MORNING
AND A LAND BREEZE THAT HAS A GOOD CHANCE OF KEEPING THE SNOW BAND
OFFSHORE. DISCUSSED THIS WITH THE GAYLORD OFFICE AND WE BOTH CONCUR
THAT THIS IS THE MOST LIKELY SCENARIO AT THIS POINT. HAVE THEREFORE
TRIMMED POPS AND ACCUMULATIONS EXCEPT FOR THE IMMEDIATE COAST.
STILL LOOKING FAVORABLE FOR LIGHT LAKE ENHANCED SNOW FRIDAY AHEAD OF
THE NEXT CLIPPER. DID NOT CHANGE THE INHERITED FORECAST
SIGNIFICANTLY. FROM FRIDAY NIGHT THROUGH SATURDAY POPS INCREASE FROM
NORTHWEST TO SOUTHEAST AHEAD OF THE CLIPPER AND ASSOCIATED COLD
FRONT WHICH SHOULD BE ENTERING THE FORECAST AREA BY SATURDAY EVENING.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 328 PM EST THU JAN 2 2014
THE MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT ON THE LARGE
SCALE FLOW WITH MINOR DIFFERENCES IN THE SMALLER SCALE FEATURES.
CONFIDENCE IS HIGH DUE TO CONTINUITY IN TIME AND SPACE. WIND CHILL
VALUES AND SNOWFALL ARE THE CHALLENGES WITH THIS FORECAST PACKAGE.
TEMPERATURES WILL FALL TO 0-5 DEGREES SUNDAY NIGHT AND ON MONDAY THE
HIGHS WILL BE AROUND 5 DEGREES ABOVE ZERO. THE LOWS MONDAY NIGHT
WILL BE BELOW ZERO. VALUES THIS LOW HAVE NOT BEEN SEEN IN THIS AREA
SINCE FEB 2007. THE TEMPERATURES WILL BEGIN TO RECOVER WEDNESDAY.
ALONG WITH THE COLD AIR... STRONG GUSTY WINDS OUT OF THE WEST AND
NORTHWEST WILL PRODUCE LOW WIND CHILL VALUES. THE COLDEST WIND
CHILLS... BETWEEN 20 AND 30 DEGREES BELOW ZERO ARE POSSIBLE MONDAY
EVENING INTO TUESDAY MORNING. A WIND CHILL ADVISORY AND MAYBE A WIND
CHILL WARNING WILL BE NEEDED MONDAY AFTERNOON THROUGH TUESDAY
AFTERNOON.
THIS ALSO SEEMS TO BE A SNOWY PERIOD OF TIME. AN UPPER LOW WILL DROP
SOUTH FROM NEAR THE POLE AND MOVE EAST ACROSS SOTHERN CANADA THROUGH
THE LONG TERM. THIS AND SHORTWAVES MOVING THROUGH THE FLOW AROUND
THE LOW WILL BRING THE COLD AIR... CYCLONIC FLOW AND SNOW. A FEW
SHORTWAVES SHOULD PASS CLOSE ENOUGH TO THE AREA TO RESULT IN SNOW
SATURDAY NIGHT THROUGH SUNDAY NIGHT. THE UPPER LOW WILL HELP TO BUMP
UP THE LAKE EFFECT SNOW MONDAY INTO WEDNESDAY AS THE SYSTEM PULLS
AWAY. WITH THE COLD TEMPERATURES... THE LAKE EFFECT SNOW IS EXPECTED
TO BE IN THE FORM OF SMALL ICE CRYSTALS. THEREFORE THE SNOW WILL NOT
STACK UP... BUT THE STRONG WINDS WILL BLOW THIS SNOW AROUND. THIS
WILL RESULT IN GREATLY REDUCED VISIBILITIES. THIS WILL ESPECIALLY BE
TRUE NEAR LAKE MICHIGAN.
A MORE ZONAL FLOW PATTERN WILL ENSUE WEDNESDAY... AS A LOW PRESSURE
SYSTEM BEGINS MOVING BY TO THE SOUTH OF THE REGION. THIS HAS THE
POTENTIAL FOR ADDITIONAL SNOWFALL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1254 PM EST THU JAN 2 2014
THE BAND OF SNOW IS FINALLY DIMINISHING AND PULLING OUT OF THE
FORECAST AREA. IFR VISIBILITIES CONTINUE FOR THE SOUTHERN TAF SITES
AND LANSING. RADAR INDICATES LANSING SHOULD BE CLEAR OF THE BAND IN
AN HOUR... WITH KALAMAZOO AND BATTLE CREEK IMPROVING IN ONE TO TWO
HOURS. JACKSON SHOULD CONTINUE IN THE SNOW FOR MAYBE THREE HOURS.
MVFR/VFR CEILINGS WILL IMPROVE TO VFR TONIGHT. THERE IS A CHANCE OF
SOME LAKE EFFECT SNOW MOVING OVER MUSKEGON EARLY FRIDAY WITH MVFR
CONDITIONS POSSIBLE.
WINDS OUT OF THE NORTH AND NORTHEAST AT 10 TO 15 KNOTS WITH GUSTS TO
20 KNOTS WILL FALL TO UNDER 10 KNOTS TONIGHT.
&&
.MARINE...
ISSUED AT 330 AM EST THU JAN 2 2014
ISSUED A SMALL CRAFT ADVISORY FROM 18Z TODAY THROUGH 18Z FRIDAY.
SOUTHWEST WINDS WILL PICK UP IN ADVANCE OF THE NEXT CLIPPER. ALSO
ISSUED A GALE WATCH FOR FRIDAY NIGHT AND SATURDAY. WINDS BEHIND THE
ARCTIC FRONT WILL BE RATHER GUSTY.
&&
.HYDROLOGY...
ISSUED AT 236 PM EST THU JAN 2 2014
A FLOOD ADVISORY IS IN EFFECT FOR THE FLAT RIVER AT SMYRNA. A
SUSPECTED ICE JAM UPSTREAM IS CAUSING A SHARP RISE AT THE SMYRNA
RIVER GAUGE. THE ICE JAM ON THE MUSKEGON RIVER THAT HAS IMPACTED
EVART SEEMS TO HAVE STABILIZED. THE MUSKEGON RIVER AT EVART IS NOW
ON A GRADUAL DECLINE. THE FLOOD ADVISORIES FOR THE MUSKEGON RIVER AT
EVART AND THE PERE MARQUETTE RIVER AT SCOTTVILLE HAVE BEEN CANCELED.
RIVERS WILL CONTINUE GAINING ICE COVERAGE AND THICKNESS FOR THE
FORESEEABLE FUTURE. THOSE RIVERS THAT ICE OVER COMPLETELY WILL HAVE
A MINIMAL ICE JAM THREAT. RIVERS WITH JAGGED ICE BUILDUP ARE IN
DANGER OF EXPERIENCING JAMMING AND RAPID FLUCTUATIONS. WIDESPREAD
HEAVIER SNOW IS LIKELY SUNDAY AND SUNDAY NIGHT...FOLLOWED
IMMEDIATELY BY A BLAST OF EXTREMELY COLD AIR. HOPEFULLY RIVER LEVELS
WILL LOCK IN SOMEWHAT WITH THE COLD AIR IN PLACE.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...GALE WATCH FROM FRIDAY EVENING THROUGH SATURDAY AFTERNOON FOR
LMZ844>849.
SMALL CRAFT ADVISORY UNTIL 1 PM EST FRIDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...EBW
SHORT TERM...TJT
LONG TERM...63
AVIATION...63
HYDROLOGY...EBW
MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
305 PM EST THU JAN 2 2014
LATEST UPDATE...
SHORT TERM
.SYNOPSIS...
ISSUED AT 236 PM EST THU JAN 2 2014
THE BIG WEATHER STORY IS THE COLD OUTBREAK EXPECTED EARLY NEXT WEEK.
HIGHS IN THE SINGLE DIGITS AND LOWS IN THE 0 TO 10 BELOW RANGE ARE
EXPECTED. WIND CHILLS COULD DROP AS LOW AS 25 BELOW ON MONDAY AND
TUESDAY. WIND GUSTS ARE FORECAST TO BE AROUND 20 TO 30 MPH.
ANOTHER VERY COLD NIGHT IS IN STORE WITH LOWS IN THE 0 TO 5 BELOW
RANGE. SOME LIGHT SNOW NEAR THE LAKESHORE IS POSSIBLE FRIDAY.
WIDESPREAD HEAVIER SNOW WILL MOVE IN SUNDAY AND SUNDAY NIGHT.
SIGNIFICANT ACCUMULATIONS APPEAR LIKELY AT THIS TIME...ESPECIALLY
SOUTH AND EAST OF GRAND RAPIDS.
TEMPERATURES WILL MODERATE CONSIDERABLY ON SATURDAY BEFORE THE
ARCTIC AIR PLUNGES BACK IN. HIGHS ON SATURDAY WILL BE NEAR 30
DEGREES.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 303 PM EST THU JAN 2 2014
MAIN CHALLENGE IN THE VERY SHORT TERM IS ASSESSING SNOW POTENTIAL
NEAR THE LAKESHORE...PARTICULARLY AROUND THE SABLE POINTS OF MASON
AND OCEANA COUNTIES. A DOMINANT LAKE SNOW BAND NEAR THE WESTERN LAKE
MICHIGAN SHORELINE THIS MORNING IS SLOWLY DRIFTING EAST. THE LAST
SEVERAL HRRR MODEL RUNS...AS WELL AS THE NAM...APPEAR TO BE PLACING
OR MOVING THIS FEATURE TOO FAR EAST TOWARDS THE POINTS.
IT IS LOOKING MORE LIKELY THAT WE WILL CLEAR OUT OVER INLAND ZONES
TONIGHT...ALLOWING FOR VERY COLD INLAND TEMPERATURES FRIDAY MORNING
AND A LAND BREEZE THAT HAS A GOOD CHANCE OF KEEPING THE SNOW BAND
OFFSHORE. DISCUSSED THIS WITH THE GAYLORD OFFICE AND WE BOTH CONCUR
THAT THIS IS THE MOST LIKELY SCENARIO AT THIS POINT. HAVE THEREFORE
TRIMMED POPS AND ACCUMULATIONS EXCEPT FOR THE IMMEDIATE COAST.
STILL LOOKING FAVORABLE FOR LIGHT LAKE ENHANCED SNOW FRIDAY AHEAD OF
THE NEXT CLIPPER. DID NOT CHANGE THE INHERITED FORECAST
SIGNIFICANTLY. FROM FRIDAY NIGHT THROUGH SATURDAY POPS INCREASE FROM
NORTHWEST TO SOUTHEAST AHEAD OF THE CLIPPER AND ASSOCIATED COLD
FRONT WHICH SHOULD BE ENTERING THE FORECAST AREA BY SATURDAY EVENING.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EST THU JAN 2 2014
DANGEROUSLY COLD AIR... THAT WE HAVE NOT SEEN SINCE FEB 2007... WILL
SWEEP INTO MICHIGAN ON MONDAY WITH WIND CHILLS FALLING TO AS LOW AS
-25 BY THE END OF THE DAY. THIS COULD HAVE SIGNIFICANT IMPACT
ESPECIALLY SINCE IT IS THE FIRST DAY BACK TO SCHOOL OR WORK FOR
MANY.
PRIOR TO THE ARRIVAL OF THE COLD AIR... WE MAY SEE A DECENT ROUND OF
SYNOPTIC SNOW ON SUNDAY AND SUNDAY NIGHT AS A SFC LOW PASSES THROUGH
THE OHIO VALLEY REGION. SEVERAL INCHES APPEAR POSSIBLE MAINLY FOR
AREAS SOUTH AND EAST OF GRR... BUT THE EXACT TRACK OF THE SYSTEM IS
STILL UNCLEAR.
LAKE EFFECT SNOW SHOWERS WILL ACCOMPANY THE BITTERLY COLD AIR ON
MONDAY AND MONDAY NIGHT ALTHOUGH LITTLE ACCUMULATION IS EXPECTED
DURING THIS TIME SINCE THE VERY COLD AIR WILL LEAD TO VERY
SMALL/FINE FLAKE SIZE. HOWEVER SOME BLOWING SNOW IS LIKELY AT LEAST
ALONG THE LAKESHORE WHERE WINDS SHOULD BE QUITE STRONG WITH GUSTS TO
40-45 MPH. THIS WILL LIMIT VISIBILITIES AND PROBABLY CREATE SOME
TRAVEL ISSUES DESPITE THE LIMITED ACCUMULATIONS.
THE REALLY COLD -30C H8 AIR LINGERS INTO TUESDAY THEN LIFTS OUT BY
MID WEEK. LAKE EFFECT SNOWS COULD INCREASE DURING THIS TIME AS THE
DGZ LIFTS BACK INTO THE CLOUD LAYER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1254 PM EST THU JAN 2 2014
THE BAND OF SNOW IS FINALLY DIMINISHING AND PULLING OUT OF THE
FORECAST AREA. IFR VISIBILITIES CONTINUE FOR THE SOUTHERN TAF SITES
AND LANSING. RADAR INDICATES LANSING SHOULD BE CLEAR OF THE BAND IN
AN HOUR... WITH KALAMAZOO AND BATTLE CREEK IMPROVING IN ONE TO TWO
HOURS. JACKSON SHOULD CONTINUE IN THE SNOW FOR MAYBE THREE HOURS.
MVFR/VFR CEILINGS WILL IMPROVE TO VFR TONIGHT. THERE IS A CHANCE OF
SOME LAKE EFFECT SNOW MOVING OVER MUSKEGON EARLY FRIDAY WITH MVFR
CONDITIONS POSSIBLE.
WINDS OUT OF THE NORTH AND NORTHEAST AT 10 TO 15 KNOTS WITH GUSTS TO
20 KNOTS WILL FALL TO UNDER 10 KNOTS TONIGHT.
&&
.MARINE...
ISSUED AT 330 AM EST THU JAN 2 2014
ISSUED A SMALL CRAFT ADVISORY FROM 18Z TODAY THROUGH 18Z FRIDAY.
SOUTHWEST WINDS WILL PICK UP IN ADVANCE OF THE NEXT CLIPPER. ALSO
ISSUED A GALE WATCH FOR FRIDAY NIGHT AND SATURDAY. WINDS BEHIND THE
ARCTIC FRONT WILL BE RATHER GUSTY.
&&
.HYDROLOGY...
ISSUED AT 236 PM EST THU JAN 2 2014
A FLOOD ADVISORY IS IN EFFECT FOR THE FLAT RIVER AT SMYRNA. A
SUSPECTED ICE JAM UPSTREAM IS CAUSING A SHARP RISE AT THE SMYRNA
RIVER GAUGE. THE ICE JAM ON THE MUSKEGON RIVER THAT HAS IMPACTED
EVART SEEMS TO HAVE STABILIZED. THE MUSKEGON RIVER AT EVART IS NOW
ON A GRADUAL DECLINE. THE FLOOD ADVISORIES FOR THE MUSKEGON RIVER AT
EVART AND THE PERE MARQUETTE RIVER AT SCOTTVILLE HAVE BEEN CANCELED.
RIVERS WILL CONTINUE GAINING ICE COVERAGE AND THICKNESS FOR THE
FORESEEABLE FUTURE. THOSE RIVERS THAT ICE OVER COMPLETELY WILL HAVE
A MINIMAL ICE JAM THREAT. RIVERS WITH JAGGED ICE BUILDUP ARE IN
DANGER OF EXPERIENCING JAMMING AND RAPID FLUCTUATIONS. WIDESPREAD
HEAVIER SNOW IS LIKELY SUNDAY AND SUNDAY NIGHT...FOLLOWED
IMMEDIATELY BY A BLAST OF EXTREMELY COLD AIR. HOPEFULLY RIVER LEVELS
WILL LOCK IN SOMEWHAT WITH THE COLD AIR IN PLACE.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...GALE WATCH FROM FRIDAY EVENING THROUGH SATURDAY AFTERNOON FOR
LMZ844>849.
SMALL CRAFT ADVISORY UNTIL 1 PM EST FRIDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...EBW
SHORT TERM...TJT
LONG TERM...MEADE
AVIATION...63
HYDROLOGY...EBW
MARINE...93
AREA FORECAST DISCUSSION
NWS BILLINGS MT
901 AM MST THU JAN 2 2014
.UPDATE...
SOMEWHAT EXTENSIVE UPDATE THIS MORNING. ISSUED A WIND ADVISORY FOR
THE BIG TIMBER AREA...WITH SUSTAINED WINDS AROUND 40 MPH...AND
OCCASIONAL GUSTS NEAR 60 MPH INTO FRIDAY....AND INCREASED
ASSOCIATED WINDS TO CORRESPOND TO ADVISORY.
ALSO EXTENDED THE DENSE FOG ADVISORY UNTIL 18Z FOR NORTHERN
ROSEBUD AND CUSTER COUNTIES. OBSERVATION IN MILES CITY ARE STILL
REPORTING 1/4 MILE VISIBILITY...AND SOUNDINGS INDICATE NO
IMPROVEMENT UNTIL LATER THIS MORNING AS WINDS STAY VERY LIGHT.
FINALLY...INCREASED MOUNTAIN POPS SLIGHTLY FOR WESTERN
MOUNTAINS...AS SHORTWAVE THE CROSSING THE REGION IS BRINGING A
BIT MORE PRECIP THERE THAN EXPECTED. CONSIDERED SPREADING SLIGHT
POPS ACROSS THE PLAINS WITH THIS WAVE AS WELL...BUT ANY PRECIP
THAT IS OCCURRING DOES NOT APPEAR TO BE REACHING THE GROUND...AND
SHOULD BE MAINLY FLURRIES AT BEST IF IT WERE TO REACH THE GROUND.
OTHERWISE THE GOING FORECAST APPEARS IN GOOD SHAPE OVERALL. AAG
&&
.SHORT TERM...VALID FOR TDY AND FRI...
WE ISSUED A DENSE FOG ADVISORY FOR PORTIONS OF CUSTER AND ROSEBUD
COUNTIES EARLIER TONIGHT. THE MLS ASOS HAS BEEN CONSISTENTLY AT
1/4 MILE VISIBILITY AND OBSERVATIONS SUGGEST NEAR 100 PERCENT
HUMIDITY ACROSS THE NORTHERN SECTIONS OF EACH COUNTY. SPOTTER
REPORTS WERE THAT THE FOG IS WIDESPREAD AND QUITE DENSE. THIS
ADVISORY WILL GO UNTIL 9 AM AS HRRR REDUCES THE HUMIDITY IN THIS
AREA A COUPLE OF HOURS AFTER SUNRISE.
THE NEXT FORECAST ISSUE TO ADDRESS IS THE WIND IN THE GAP FLOW
LOCATIONS OF LIVINGSTON...NYE AND NEARBY AREAS. PRESSURE
GRADIENTS ARE ALREADY INCREASING ACROSS THIS REGION AND ARE
PROGGED TO CONTINUE THROUGH TONIGHT. WINDS AT LIVINGSTON HAVE BEEN
GUSTING TO NEAR 50 MPH OVERNIGHT ALREADY. DOWNWARD MOMENTUM PEAKS
LATE TONIGHT OVER A VERY IMPRESSIVE PRESSURE GRADIENT. AS COLD
FRONT HITS AREA FROM NW FRIDAY MORNING WE COULD SEE SOME EXCESSIVE
HYBRID TYPE GUSTS AS 55 TO 60 KTS WILL BE JUST OFF THE
GROUND...AND UP TO 70 KTS AT 700MB ACCORDING TO THE WRF. SO
DESPITE THE PRESSURE GRADIENT GOING TO WESTERLY FOR GAP FLOW BY 11
AM FRIDAY...THE THREAT OF HIGH WIND MAY NOT COMPLETELY END.
THEREFORE...WILL UPGRADE HIGH WIND WATCH TO A WARNING FROM 6 AM
TODAY THROUGH 5 PM FRIDAY. THE STRONGEST WINDS SHOULD OCCUR
BETWEEN 6 PM THIS EVENING TO ABOUT 8 AM FRIDAY MORNING.
I AM CONCERNED WE MAY NEED HIGHLIGHTS FOR HARLOWTON/BIG TIMBER
LOCATIONS AS WELL DUE TO INCREASING 700MB WIND SPEEDS BY FRIDAY.
ANY PERIOD OF STRONG WIND LOOKS SHORTLIVED AT BEST AT HARLOWTON.
I HAVE RAISED WINDS SPEEDS IN THESE AREAS AND WILL LET NEXT
ANALYZE ANOTHER ROUND OF DATA...AS MODELS OFTEN FLIP FLOP ON MID
LEVEL WIND SPEEDS CLOSE TO AN EVENT.
TEMPERATURES WILL BE RELATIVELY MILD FRIDAY...BUT HAVE LOWERED
THEM A NOTCH DUE TO CLOUD COVER AND SOME PRECIPITATION FRIDAY
AFTERNOON. I EXPECT A BLUSTERY FRONTAL PASSAGE FOR THE LATTER HALF
OF FRIDAY TO PRODUCE SCATTERED RAIN AND SNOW SHOWERS. WIND WILL BE
WESTERLY AND BRISK AT FIRST PRODUCING A DOWNSLOPE EFFECT IN MANY
AREAS...BUT DECREASE BY EVENING. IN THE MEANTIME...SOME DECENT Q
VECTOR FORCING WILL CONTINUE OVER THE AREA FRIDAY EVENING...SO
THIS MAY BE BEST CHANCE FOR MEASURABLE PRECIPITATION IN THE SHORT
TERM PERIOD. BT
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
MODELS CONTINUE TO LINE UP WELL...FORECASTING AN UPPER LEVEL
RIDGE JUST OFF THE PACIFIC COAST ON SATURDAY...WHICH MOVES OVER
THE PACIFIC COAST DURING THE DAY SUNDAY. THIS SETS US UP FOR
HIGHLY AMPLIFIED NW FLOW IN THE WAKE OF THE FRIDAY FROPA AND
ALLOWS A COUPLE OF STRONG SURGES OF ARCTIC AIR TO MOVE INTO THE
REGION OVER THE WEEKEND. EACH OF THESE SURGES WILL INCREASE LOW-
LEVEL FRONTOGENESIS AND STRENGTHEN A LOW LEVEL BAROCLINIC ZONE
ACROSS WESTERN AND CENTRAL AREAS. AT THE SAME TIME...A SERIES OF
SHORTWAVES IS EXPECTED TO MOVE THROUGH THE REGION...HELPING TO
INCREASE PVA AND MID- LEVEL FRONTOGENESIS...AND THE REGION WILL BE
INFLUENCED BY STRONG 300 MB JET ENERGY. THESE FACTORS WILL LEAD TO
ENHANCED LIFT THROUGH THE DENDRITIC GROWTH ZONE...SO PERIODS OF
SNOW ARE LIKELY ACROSS THE REGION...PARTICULARLY WESTERN AND
CENTRAL AREAS...DURING THE DAY SATURDAY...AND AGAIN LATE SATURDAY
NIGHT INTO SUNDAY MORNING. INCREASED PRECIP CHANCES AND SNOW
AMOUNTS TO REFLECT THIS. SIMILAR SCENARIOS IN THE PREVIOUS FEW
WEEKS RESULTED IN SEVERAL INCHES OF SNOW ACROSS WESTERN AND
CENTRAL AREAS. AVERAGE SNOWFALL FROM CURRENT SREF PLUMES IS JUST
OVER 3 INCHES IN THE BILLINGS REGION SATURDAY INTO SUNDAY. THERE
IS GOOD CLUSTERING IN THE 3 TO 5 INCH RANGE...WHICH SEEMS
REASONABLE.
BESIDES THE SNOW...THE OTHER BIG FACTOR WILL BE THE VERY COLD AIR
THAT MOVES BACK INTO THE REGION. BOTH THE GFS AND ECMWF DROP 850
MB TEMPS TO TO -30C TO -33C RANGE FROM MILES CITY AND BROADUS EAST
DURING THE DAY SUNDAY...SO HIGH TEMPS MAY BE WELL BELOW ZERO ACROSS
THE EAST BY SUNDAY...WITH LOWS COLDER THAN -20F SUNDAY NIGHT.
NW WINDS MAY DROP WIND CHILL VALUES TO BELOW -45F SUNDAY NIGHT IN
PLACES LIKE MILES CITY...BAKER AND EKALAKA.
ECMWF/GFS ARE ALSO VERY SIMILAR IN STARTING TO ERODE THE COLD AIR
OUT OF THE AREA LATE MONDAY AS THE UPPER LEVEL RIDGE CONTINUES TO
MOVE EAST. INCREASING HEIGHTS WILL BRING MODERATING
TEMPERATURES...WITH HIGHS CLIMBING BACK INTO THE 20S AND 30S AGAIN
BY TUESDAY. SOME WEAK SHORTWAVE ACTIVITY MAY BRING THE THREAT OF
SNOW SHOWERS TO THE WESTERN MOUNTAINS LATE TUESDAY INTO
WEDNESDAY...BUT MODELS DIFFER ON TIMING AND STRENGTH OF THE
SHORTWAVES. STC
&&
.AVIATION...
AREAS OF FOG AND LOW CEILINGS WILL CONTINUE TO PRODUCE VLIFR TO
IFR CONDITIONS INTO LATE MORNING ACROSS THE EASTERN HALF OF THE
REGION. EXPECT CONDITIONS TO BE AT OR BELOW AIRPORT MINIMUMS AT
MILES CITY THROUGH 17Z. FLIGHT CONDITIONS ACROSS THE EAST ARE
EXPECTED TO GRADUALLY IMPROVE TO VFR BY 18Z. STRONG SW WINDS WILL
CONTINUE ACROSS THE WEST TODAY...WITH GUSTS OVER 50 KTS AT TIMES
IN THE LIVINGSTON AREA BEGINNING BY MID MORNING AND GUSTS OVER 40
KTS AT TIMES NEAR BIG TIMBER. RICHMOND
&&
.PRELIMINARY POINT TEMP/POPS...
TDY FRI SAT SUN MON TUE WED
-------------------------------------------------------
BIL 042 037/043 017/024 007/009 912/009 005/034 017/035
0/N 03/W 44/S 44/S 11/B 12/J 21/B
LVM 046 042/044 015/022 006/013 906/018 010/035 019/035
0/N 03/W 44/S 43/S 11/B 12/J 21/B
HDN 039 024/042 012/022 003/007 916/007 002/028 015/033
0/B 04/W 54/S 44/S 11/B 12/J 21/E
MLS 032 025/039 005/015 904/903 921/903 908/016 007/025
0/B 04/W 43/S 43/S 11/I 12/J 11/E
4BQ 035 025/042 011/017 000/002 918/002 905/022 011/030
0/B 04/W 52/S 44/S 11/B 10/B 11/E
BHK 029 023/040 006/012 908/906 922/906 913/014 001/023
0/E 04/W 52/S 42/S 11/I 11/B 11/E
SHR 040 025/045 012/021 004/009 915/010 003/031 013/032
0/B 02/W 53/S 44/S 11/B 10/B 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...DENSE FOG ADVISORY IN EFFECT UNTIL 11 AM MST THIS MORNING FOR
ZONES 31-32.
WIND ADVISORY IN EFFECT UNTIL 5 PM MST FRIDAY FOR ZONE 41.
HIGH WIND WARNING IN EFFECT UNTIL 5 PM MST FRIDAY FOR ZONES
65-66.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
312 AM MST THU JAN 2 2014
.SHORT TERM...VALID FOR TDY AND FRI...
WE ISSUED A DENSE FOG ADVISORY FOR PORTIONS OF CUSTER AND ROSEBUD
COUNTIES EARLIER TONIGHT. THE MLS ASOS HAS BEEN CONSISTENTLY AT
1/4 MILE VISIBILITY AND OBSERVATIONS SUGGEST NEAR 100 PERCENT
HUMIDITY ACROSS THE NORTHERN SECTIONS OF EACH COUNTY. SPOTTER
REPORTS WERE THAT THE FOG IS WIDESPREAD AND QUITE DENSE. THIS
ADVISORY WILL GO UNTIL 9 AM AS HRRR REDUCES THE HUMIDITY IN THIS
AREA A COUPLE OF HOURS AFTER SUNRISE.
THE NEXT FORECAST ISSUE TO ADDRESS IS THE WIND IN THE GAP FLOW
LOCATIONS OF LIVINGSTON...NYE AND NEARBY AREAS. PRESSURE
GRADIENTS ARE ALREADY INCREASING ACROSS THIS REGION AND ARE
PROGGED TO CONTINUE THROUGH TONIGHT. WINDS AT LIVINGSTON HAVE BEEN
GUSTING TO NEAR 50 MPH OVERNIGHT ALREADY. DOWNWARD MOMENTUM PEAKS
LATE TONIGHT OVER A VERY IMPRESSIVE PRESSURE GRADIENT. AS COLD
FRONT HITS AREA FROM NW FRIDAY MORNING WE COULD SEE SOME EXCESSIVE
HYBRID TYPE GUSTS AS 55 TO 60 KTS WILL BE JUST OFF THE
GROUND...AND UP TO 70 KTS AT 700MB ACCORDING TO THE WRF. SO
DESPITE THE PRESSURE GRADIENT BECOMING TO WESTERLY FOR GAP FLOW
BY 11 AM FRIDAY...THE THREAT OF HIGH WIND MAY NOT COMPLETELY END.
THEREFORE...WILL UPGRADE HIGH WIND WATCH TO A WARNING FROM 6 AM
TODAY THROUGH 5 PM FRIDAY. THE STRONGEST WINDS SHOULD OCCUR
BETWEEN 6 PM THIS EVENING TO ABOUT 8 AM FRIDAY MORNING.
I AM CONCERNED WE MAY NEED HIGHLIGHTS FOR HARLOWTON/BIG TIMBER
LOCATIONS AS WELL DUE TO INCREASING 700MB WIND SPEEDS. BUT...ANY
PERIOD OF STRONG WIND LOOKS SHORTLIVED AT BEST AT HARLOWTON. I
HAVE RAISED WINDS SPEEDS IN THESE AREAS AND WILL LET NEXT ANALYZE
ANOTHER ROUND OF DATA...AS MODELS OFTEN FLIP FLOP ON MID LEVEL
WIND SPEEDS CLOSE TO AN EVENT.
TEMPERATURES WILL BE RELATIVELY MILD THE NEXT COUPLE OF
DAYS...BUT HAVE LOWERED THEM A NOTCH FRIDAY DUE TO CLOUD COVER AND
SOME PRECIPITATION FRIDAY AFTERNOON. I EXPECT A BLUSTERY FRONTAL
PASSAGE FOR THE LATTER HALF OF FRIDAY TO PRODUCE SCATTERED RAIN
AND SNOW SHOWERS. WIND WILL BE WESTERLY AND BRISK AT FIRST
PRODUCING A DOWNSLOPE EFFECT IN MANY AREAS...BUT DECREASE BY
EVENING. IN THE MEANTIME...SOME DECENT Q VECTOR FORCING WILL
CONTINUE OVER THE AREA FRIDAY EVENING...SO THIS MAY BE BEST CHANCE
FOR MEASURABLE PRECIPITATION IN THE SHORT TERM PERIOD. BT
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
MODELS CONTINUE TO LINE UP WELL...FORECASTING AN UPPER LEVEL
RIDGE JUST OFF THE PACIFIC COAST ON SATURDAY...WHICH MOVES OVER
THE PACIFIC COAST DURING THE DAY SUNDAY. THIS SETS US UP FOR
HIGHLY AMPLIFIED NW FLOW IN THE WAKE OF THE FRIDAY FROPA AND
ALLOWS A COUPLE OF STRONG SURGES OF ARCTIC AIR TO MOVE INTO THE
REGION OVER THE WEEKEND. EACH OF THESE SURGES WILL INCREASE LOW-
LEVEL FRONTOGENESIS AND STRENGTHEN A LOW LEVEL BAROCLINIC ZONE
ACROSS WESTERN AND CENTRAL AREAS. AT THE SAME TIME...A SERIES OF
SHORTWAVES IS EXPECTED TO MOVE THROUGH THE REGION...HELPING TO
INCREASE PVA AND MID- LEVEL FRONTOGENESIS...AND THE REGION WILL BE
INFLUENCED BY STRONG 300 MB JET ENERGY. THESE FACTORS WILL LEAD TO
ENHANCED LIFT THROUGH THE DENDRITIC GROWTH ZONE...SO PERIODS OF
SNOW ARE LIKELY ACROSS THE REGION...PARTICULARLY WESTERN AND
CENTRAL AREAS...DURING THE DAY SATURDAY...AND AGAIN LATE SATURDAY
NIGHT INTO SUNDAY MORNING. INCREASED PRECIP CHANCES AND SNOW
AMOUNTS TO REFLECT THIS. SIMILAR SCENARIOS IN THE PREVIOUS FEW
WEEKS RESULTED IN SEVERAL INCHES OF SNOW ACROSS WESTERN AND
CENTRAL AREAS. AVERAGE SNOWFALL FROM CURRENT SREF PLUMES IS JUST
OVER 3 INCHES IN THE BILLINGS REGION SATURDAY INTO SUNDAY. THERE
IS GOOD CLUSTERING IN THE 3 TO 5 INCH RANGE...WHICH SEEMS
REASONABLE.
BESIDES THE SNOW...THE OTHER BIG FACTOR WILL BE THE VERY COLD AIR
THAT MOVES BACK INTO THE REGION. BOTH THE GFS AND ECMWF DROP 850
MB TEMPS TO TO -30C TO -33C RANGE FROM MILES CITY AND BROADUS EAST
DURING THE DAY SUNDAY...SO HIGH TEMPS MAY BE WELL BELOW ZERO ACROSS
THE EAST BY SUNDAY...WITH LOWS COLDER THAN -20F SUNDAY NIGHT.
NW WINDS MAY DROP WIND CHILL VALUES TO BELOW -45F SUNDAY NIGHT IN
PLACES LIKE MILES CITY...BAKER AND EKALAKA.
ECMWF/GFS ARE ALSO VERY SIMILAR IN STARTING TO ERODE THE COLD AIR
OUT OF THE AREA LATE MONDAY AS THE UPPER LEVEL RIDGE CONTINUES TO
MOVE EAST. INCREASING HEIGHTS WILL BRING MODERATING
TEMPERATURES...WITH HIGHS CLIMBING BACK INTO THE 20S AND 30S AGAIN
BY TUESDAY. SOME WEAK SHORTWAVE ACTIVITY MAY BRING THE THREAT OF
SNOW SHOWERS TO THE WESTERN MOUNTAINS LATE TUESDAY INTO
WEDNESDAY...BUT MODELS DIFFER ON TIMING AND STRENGTH OF THE
SHORTWAVES. STC
&&
.AVIATION...
AREAS OF FOG AND LOW CEILINGS WILL CONTINUE TO PRODUCE VLIFR TO
IFR CONDITIONS INTO LATE THIS MORNING ACROSS THE EASTERN HALF OF
THE REGION. EXPECT CONDITIONS TO BE AT OR BELOW AIRPORT MINIMUMS
AT KMLS THROUGH 15Z. FLIGHT CONDITIONS ACROSS THE EAST ARE
EXPECTED TO GRADUALLY IMPROVE TO VFR BY 18Z. STRONG SW WINDS WILL
CONTINUE ACROSS THE WEST TODAY...WITH GUSTS OVER 50 KTS AT TIMES
IN THE KLVM REGION BEGINNING BY MID MORNING AND GUSTS OVER 40 KTS
AT TIMES NEAR 6S0. STC
&&
.PRELIMINARY POINT TEMP/POPS...
TDY FRI SAT SUN MON TUE WED
-------------------------------------------------------
BIL 042 037/043 017/024 007/009 912/009 005/034 017/035
0/N 03/W 44/J 44/J 11/B 12/J 21/B
LVM 046 042/044 015/022 006/013 906/018 010/035 019/035
0/N 03/W 44/J 43/J 11/B 12/J 21/B
HDN 039 024/042 012/022 003/007 916/007 002/028 015/033
0/B 04/W 54/J 44/J 11/B 12/J 21/E
MLS 032 025/039 005/015 904/903 921/903 908/016 007/025
0/B 04/W 42/J 43/J 11/I 12/J 11/E
4BQ 035 025/042 011/017 000/002 918/002 905/022 011/030
0/B 04/W 52/J 44/J 11/B 10/B 11/E
BHK 029 023/040 006/012 908/906 922/906 913/014 001/023
0/E 04/W 51/E 42/J 11/I 11/B 11/E
SHR 040 025/045 012/021 004/009 915/010 003/031 013/032
0/B 02/W 53/J 44/J 11/B 10/B 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...DENSE FOG ADVISORY IN EFFECT UNTIL 9 AM MST THIS MORNING FOR
ZONES 31-32.
HIGH WIND WARNING IN EFFECT UNTIL 5 PM MST FRIDAY FOR ZONES
65-66.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1209 PM CST THU JAN 2 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM CST THU JAN 2 2014
MAIN FORECAST CONCERN FOR THE SHORT TERM PERIOD LIES WITH SOME
LIGHT SNOW CHANCES AND TRICKY HIGH TEMPERATURES FOR TODAY.
QUIET CONDITIONS REMAIN IN PLACE ACROSS THE CWA EARLY THIS
MORNING...AND WE CONTINUE TO SIT UNDER NORTHWESTERLY FLOW IN THE
UPPER LEVELS AS A LARGE AREA OF LOW PRESSURE CONTINUES TO SPIN
OVER ERN CANADA...WITH YESTERDAYS SNOW-PRODUCING DISTURBANCE
MOVING INTO THE MIDWEST...WHILE RIDGING REMAINS OFF THE WEST
COAST. A STOUT ~130KT UPPER LEVEL JET STREAK NOSING IN FROM THE
NORTH BEHIND THE TROUGH AXIS...HELPING DRIVE SOME LIGHT
SNOW/FLURRIES...WITH INCREASED RADAR RETURNS JUST NORTH OF THE
CWA. SKIES ACROSS THE CWA CURRENTLY MOSTLY CLOUDY/OVERCAST THANKS
TO A BAND OF MAINLY LOWER LEVEL STRATUS STRETCHED FROM THE NRN
ROCKIES INTO CENTRAL KS. AT THE SURFACE...HIGH PRESSURE DRAPED
GENERALLY THROUGH THE ERN PORTIONS OF THE CENTRAL PLAINS IS
KEEPING WINDS ON THE LIGHT/VARIABLE SIDE...WITH MORE OF A WESTERLY
COMPONENT DEVELOPING ACROSS WRN LOCATIONS.
THIS MORNING...THAT UPPER LEVEL JET STREAK REMAINS IN THE
AREA...AND WILL CONTINUE TO BRING THE POTENTIAL FOR SOME LIGHT
SNOW/FLURRIES TO MAINLY THE NORTHEASTERN HALF OF THE CWA. WITH
UPSTREAM OBS SHOWING VISIBILITIES DROPPING AT TIMES INTO THE 2-3
MILE RANGE...PERHAPS A FEW AREAS COULD MAYBE PICK UP A TENTH OF AN
INCH OR SO OF SNOW ACCUMULATION...SO HAVE SOME LOW POPS GOING.
OTHERWISE THE REST OF THE SHORT TERM REMAINS DRY. KEPT HIGH SKY
COVER VALUES GOING THIS MORNING...BUT SATELLITE IMAGERY SUGGESTS
THE WRN EDGE OF THAT BAND OF CLOUD COVER ISNT FAR OUTSIDE THE WRN
EDGE OF THE CWA...AND MODELS ARENT IN TOO BAD OF AGREEMENT SHOWING
THE HIGHER CLOUD COVER TRANSITIONING TO MAINLY AFFECT THE
NORTHEASTERN HALF OF THE CWA...WITH MORE SUN POTENTIAL FURTHER
SOUTHWEST.
LOOKING AT TEMPERATURES...HIGHS FOR TODAY ARE TRICKY...AND
CONFIDENCE IS NOT HIGH. WHILE WINDS ARE MAINLY ON THE
LIGHT/VARIABLE TO WESTERLY SIDE CURRENTLY...MODELS SHOW THE CWA
BEING AFFECTED BY A BACKDOOR COLD FRONT SLIDING IN FROM THE
NORTH/NORTHEAST THIS MORNING...AND THE POSITION OF THIS FRONT
THROUGH THE DAY WILL HAVE A BIG IMPACT ON WHAT TEMPS GET TO TODAY.
THERE ARE DIFFERENCES BETWEEN MODELS WITH TIMING/LOCATION. LOOKING
AT MIDDAY...THE 07Z HRRR AND 09Z RAP /THE RAP HAS DONE FAIRLY
WELL THE LAST FEW DAYS WITH HIGHS/ SHOW THE FRONT ROUGHLY ALONG A
BBW TO CNK LINE THROUGH THE CWA...VS OTHER MODELS WHICH FURTHER
WEST BY THEN...CLOSER TO A LBF TO RSL LINE. MAYBE NOT A HUGE
DIFFERENCE...BUT THE SLOWER PROGRESS OF THE BOUNDARY...WITH THE
WESTERLY WINDS AHEAD OF THE FRONT...WOULD ALLOW WRN AND POSSIBLY
CENTRAL PORTIONS OF THE CWA /INCLUDING THE TRI CITIES/ TO REACH
HIGHER TEMPS BEFORE THE EASTERLY WINDS ACCOMPANYING THE FRONT TAKE
OVER AND TEMPS DONT REALLY GO ANYWHERE. THIS LOOKS TO BE THE STORY
WITH NERN PORTIONS OF THE CWA...WHICH WILL COME UNDER THE
INFLUENCE OF THOSE E/NERLY WINDS EARLY ON IN THE DAY. DONT WANT TO
COMPLETELY DISCOUNT OR BUY FULLY INTO WHAT THE RAP/HRRR
SUGGEST...SO HIGHS ARE A BLEND...RANGING FROM ARND 10 DEGREES IN
THE NORTHEAST...TO MID 30S IN THE SW. OVERNIGHT LOWS TONIGHT LOOK
TO FALL BACK INTO THE LOW SINGLE DIGITS EAST TO MID TEENS WEST.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 409 AM CST THU JAN 2 2014
GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC AND SREF-MEAN ALL
SUGGEST A MID LEVEL SHORT WAVE WILL MOVE FROM THE NORTHWESTERN
CONUS...SOUTHEAST INTO PORTIONS OF THE CENTRAL PLAINS FRIDAY INTO
SATURDAY. THE NAM SUGGESTS A NEARLY CONTINUOUS ~70KT MID LEVEL JET
STREAM AXIS WILL EXTEND FROM COLORADO TO THE GREAT LAKES REGION AT
18Z SATURDAY. THE OPERATIONAL GFS AND EC ON THE OTHER HAND BOTH
SUGGEST A BREAK IN THIS MID LEVEL JET AXIS OVER THE CENTRAL PLAINS
WILL ALLOW THE RIGHT-REAR QUADRANT OF A DEPARTING JET STREAK...AND
THE LEFT-FRONT QUADRANT OF AN INCOMING JET STREAK...TO SET UP FROM
WESTERN KANSAS INTO SOUTHEASTERN NEBRASKA AT 18Z SATURDAY. DPVA
AND MID LEVEL THERMAL ADVECTION AHEAD OF THE INCOMING MID LEVEL
SHORTWAVE DO NOT APPEAR OVERLY STRONG AND THE NAM RESPONDS BY
KEEPING OUR AREA DRY THROUGH THE WEEKEND. THE OPERATIONAL GFS AND
EC ON THE OTHER HAND BOTH SUGGEST ENHANCED OMEGA DUE TO DIRECT AND
INDIRECT THERMAL CIRCULATIONS FROM THE AFOREMENTIONED JET STREAKS
WILL PROMOTE A PERIOD OF LIGHT PRECIPITATION OVER PORTIONS OF OUR
AREA SATURDAY INTO SATURDAY EVENING...PRIMARILY ACROSS OUR SOUTH.
GIVEN THIS...WENT AHEAD WITH LOW POPS ACROSS OUR SOUTH 18Z
SATURDAY THROUGH 06Z SUNDAY ACROSS OUR SOUTH. A SECONDARY MID
LEVEL SHORTWAVE IS THEN EXPECTED TO SWEEP SOUTH/SOUTHEAST ACROSS
PORTIONS OF THE NORTHERN AND CENTRAL PLAINS SUNDAY INTO SUNDAY
NIGHT...WITH ENOUGH DPVA AND MID LEVEL THERMAL ADVECTION FOR LIGHT
PRECIPITATION ACROSS OUR AREA. ALLBLEND RESPONDED BY PRESENTING
~20% POPS TO MUCH OF THE AREA AND THESE POPS WERE LEFT UNCHANGED
FOR THE MOST PART. AN OVERALL LACK IN OMEGA SHOULD THEN PROVIDE
DRY CONDITIONS THROUGH THE REMAINDER OF THE LONG TERM FORECAST
PERIOD.
INCORPORATING THE DRY NAM FORECAST FOR SATURDAY AFTERNOON AND
SATURDAY EVENING...AS WELL AS A BLEND OF THE OPERATIONAL GFS AND
EC...PROVIDES LIQUID PRECIPITATION GENERALLY IN THE 0.01-0.04"
RANGE. SURFACE TEMPERATURES DURING THIS EVENT ARE CURRENTLY
EXPECTED TO RANGE FROM THE UPPER 20S TO AROUND 15...WHICH SUGGESTS
SNOW-WATER RATIOS GENERALLY IN THE 10-20:1 RANGE. THIS PROVIDES
SNOWFALL ACCUMULATION FROM A COUPLE TENTHS OF AN INCH TO PERHAPS
ONE INCH ACROSS OUR SOUTH 18Z SATURDAY THROUGH 06Z SUNDAY.
SNOWFALL RATES ALSO DO NOT LOOK OVERLY IMPRESSIVE SUNDAY INTO
SUNDAY NIGHT WITH PERHAPS ANOTHER INCH OF SNOWFALL ACCUMULATION
POSSIBLE ACROSS MUCH OF THE CWA.
BY FAR THE BIGGEST STORY OF THE LONG TERM FORECAST PERIOD WILL BE
THE VERY COLD TEMPERATURES WHICH LOOK TO INFILTRATE OUR AREA DURING
THE EARLY PART OF NEXT WEEK. WHILE THE COLDEST LOW LEVEL AIRMASS IS
EXPECTED TO RESIDE OVER PORTIONS OF THE UPPER MISSISSIPPI VALLEY
SUNDAY THROUGH TUESDAY...OUR AREA WILL NOT BE SPARED THE AFFECTS
OF THIS FRIGID AIR MASS AS GUIDANCE SUGGESTS SUB-ZERO READINGS
WILL BE REALIZED SUNDAY NIGHT AND MONDAY NIGHT. IN
ADDITION...STRONG LOW LEVEL COLD AIR ADVECTION ON MONDAY WILL
LIKELY KEEP HIGHS IN THE SINGLE DIGITS FOR MOST LOCATIONS ACROSS
THE CWA. THESE COLD TEMPERATURES WILL HELP PROMOTE WIND CHILL
READINGS GENERALLY IN THE -15 TO -25 DEGREE RANGE ACROSS MUCH OF
THE CWA EARLY MONDAY MORNING...WITH WIND CHILL VALUES PERHAPS
APPROACHING -30 ACROSS OUR EXTREME NORTHEAST. WILL GO AHEAD AND
MAINTAIN THE WIND CHILL WORDING IN THE HWO FOR MONDAY MORNING. THE
LOW LEVEL WIND FIELD APPEARS AS THOUGH IT WILL WEAKEN CONSIDERABLY
BY TUESDAY MORNING SO EVEN THOUGH EARLY TUESDAY MORNING LOWS WILL
BE COMPARABLE TO MONDAY...WIND CHILL VALUES ON TUESDAY MORNING DO
NOT APPEAR AS THROUGH THEY WILL DROP BELOW -10 DEGREES.
&&
.AVIATION...(FOR THE 18Z KGRI TAF THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1155 AM CST THU JAN 2 2014
THE EDGE OF STRATUS ALONG A STATIONARY FRONT WILL CONTINUE TO
MEANDER NEAR KGRI THROUGH THE AFTERNOON AND EVENING HOURS...AND
EXPECT PREVAILING MVFR CIGS TO CONTINUE...ALBEIT COULD SEE SOME
BRIEF BREAKS THROUGH ABOUT 03/06Z. THEREAFTER...SKIES WILL BEGIN
TO CLEAR...BUT INCREASING SOUTHERLY WINDS ARE EXPECTED AS THE
PRESSURE GRADIENT TIGHTENS BEHIND AN AREA OF SURFACE HIGH
PRESSURE SLIDING SOUTH ACROSS MISSOURI AND ARKANSAS. COULD SEE
SOME WIND SHEAR OVERNIGHT AS THE LOW LEVEL JET WILL APPROACH 40KTS
NEAR 2KFT...BUT LEFT MENTION OUT OF CURRENT TAF AS SURFACE WINDS
WILL ALSO BE INCREASING...EVENTUALLY GUSTING OVER 20KTS BY
03/13Z.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...ADO
LONG TERM...BRYANT
AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS HASTINGS NE
546 AM CST THU JAN 2 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM CST THU JAN 2 2014
MAIN FORECAST CONCERN FOR THE SHORT TERM PERIOD LIES WITH SOME
LIGHT SNOW CHANCES AND TRICKY HIGH TEMPERATURES FOR TODAY.
QUIET CONDITIONS REMAIN IN PLACE ACROSS THE CWA EARLY THIS
MORNING...AND WE CONTINUE TO SIT UNDER NORTHWESTERLY FLOW IN THE
UPPER LEVELS AS A LARGE AREA OF LOW PRESSURE CONTINUES TO SPIN
OVER ERN CANADA...WITH YESTERDAYS SNOW-PRODUCING DISTURBANCE
MOVING INTO THE MIDWEST...WHILE RIDGING REMAINS OFF THE WEST
COAST. A STOUT ~130KT UPPER LEVEL JET STREAK NOSING IN FROM THE
NORTH BEHIND THE TROUGH AXIS...HELPING DRIVE SOME LIGHT
SNOW/FLURRIES...WITH INCREASED RADAR RETURNS JUST NORTH OF THE
CWA. SKIES ACROSS THE CWA CURRENTLY MOSTLY CLOUDY/OVERCAST THANKS
TO A BAND OF MAINLY LOWER LEVEL STRATUS STRETCHED FROM THE NRN
ROCKIES INTO CENTRAL KS. AT THE SURFACE...HIGH PRESSURE DRAPED
GENERALLY THROUGH THE ERN PORTIONS OF THE CENTRAL PLAINS IS
KEEPING WINDS ON THE LIGHT/VARIABLE SIDE...WITH MORE OF A WESTERLY
COMPONENT DEVELOPING ACROSS WRN LOCATIONS.
THIS MORNING...THAT UPPER LEVEL JET STREAK REMAINS IN THE
AREA...AND WILL CONTINUE TO BRING THE POTENTIAL FOR SOME LIGHT
SNOW/FLURRIES TO MAINLY THE NORTHEASTERN HALF OF THE CWA. WITH
UPSTREAM OBS SHOWING VISIBILITIES DROPPING AT TIMES INTO THE 2-3
MILE RANGE...PERHAPS A FEW AREAS COULD MAYBE PICK UP A TENTH OF AN
INCH OR SO OF SNOW ACCUMULATION...SO HAVE SOME LOW POPS GOING.
OTHERWISE THE REST OF THE SHORT TERM REMAINS DRY. KEPT HIGH SKY
COVER VALUES GOING THIS MORNING...BUT SATELLITE IMAGERY SUGGESTS
THE WRN EDGE OF THAT BAND OF CLOUD COVER ISNT FAR OUTSIDE THE WRN
EDGE OF THE CWA...AND MODELS ARENT IN TOO BAD OF AGREEMENT SHOWING
THE HIGHER CLOUD COVER TRANSITIONING TO MAINLY AFFECT THE
NORTHEASTERN HALF OF THE CWA...WITH MORE SUN POTENTIAL FURTHER
SOUTHWEST.
LOOKING AT TEMPERATURES...HIGHS FOR TODAY ARE TRICKY...AND
CONFIDENCE IS NOT HIGH. WHILE WINDS ARE MAINLY ON THE
LIGHT/VARIABLE TO WESTERLY SIDE CURRENTLY...MODELS SHOW THE CWA
BEING AFFECTED BY A BACKDOOR COLD FRONT SLIDING IN FROM THE
NORTH/NORTHEAST THIS MORNING...AND THE POSITION OF THIS FRONT
THROUGH THE DAY WILL HAVE A BIG IMPACT ON WHAT TEMPS GET TO TODAY.
THERE ARE DIFFERENCES BETWEEN MODELS WITH TIMING/LOCATION. LOOKING
AT MIDDAY...THE 07Z HRRR AND 09Z RAP /THE RAP HAS DONE FAIRLY
WELL THE LAST FEW DAYS WITH HIGHS/ SHOW THE FRONT ROUGHLY ALONG A
BBW TO CNK LINE THROUGH THE CWA...VS OTHER MODELS WHICH FURTHER
WEST BY THEN...CLOSER TO A LBF TO RSL LINE. MAYBE NOT A HUGE
DIFFERENCE...BUT THE SLOWER PROGRESS OF THE BOUNDARY...WITH THE
WESTERLY WINDS AHEAD OF THE FRONT...WOULD ALLOW WRN AND POSSIBLY
CENTRAL PORTIONS OF THE CWA /INCLUDING THE TRI CITIES/ TO REACH
HIGHER TEMPS BEFORE THE EASTERLY WINDS ACCOMPANYING THE FRONT TAKE
OVER AND TEMPS DONT REALLY GO ANYWHERE. THIS LOOKS TO BE THE STORY
WITH NERN PORTIONS OF THE CWA...WHICH WILL COME UNDER THE
INFLUENCE OF THOSE E/NERLY WINDS EARLY ON IN THE DAY. DONT WANT TO
COMPLETELY DISCOUNT OR BUY FULLY INTO WHAT THE RAP/HRRR
SUGGEST...SO HIGHS ARE A BLEND...RANGING FROM ARND 10 DEGREES IN
THE NORTHEAST...TO MID 30S IN THE SW. OVERNIGHT LOWS TONIGHT LOOK
TO FALL BACK INTO THE LOW SINGLE DIGITS EAST TO MID TEENS WEST.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 409 AM CST THU JAN 2 2014
GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC AND SREF-MEAN ALL
SUGGEST A MID LEVEL SHORT WAVE WILL MOVE FROM THE NORTHWESTERN
CONUS...SOUTHEAST INTO PORTIONS OF THE CENTRAL PLAINS FRIDAY INTO
SATURDAY. THE NAM SUGGESTS A NEARLY CONTINUOUS ~70KT MID LEVEL JET
STREAM AXIS WILL EXTEND FROM COLORADO TO THE GREAT LAKES REGION AT
18Z SATURDAY. THE OPERATIONAL GFS AND EC ON THE OTHER HAND BOTH
SUGGEST A BREAK IN THIS MID LEVEL JET AXIS OVER THE CENTRAL PLAINS
WILL ALLOW THE RIGHT-REAR QUADRANT OF A DEPARTING JET STREAK...AND
THE LEFT-FRONT QUADRANT OF AN INCOMING JET STREAK...TO SET UP FROM
WESTERN KANSAS INTO SOUTHEASTERN NEBRASKA AT 18Z SATURDAY. DPVA
AND MID LEVEL THERMAL ADVECTION AHEAD OF THE INCOMING MID LEVEL
SHORTWAVE DO NOT APPEAR OVERLY STRONG AND THE NAM RESPONDS BY
KEEPING OUR AREA DRY THROUGH THE WEEKEND. THE OPERATIONAL GFS AND
EC ON THE OTHER HAND BOTH SUGGEST ENHANCED OMEGA DUE TO DIRECT AND
INDIRECT THERMAL CIRCULATIONS FROM THE AFOREMENTIONED JET STREAKS
WILL PROMOTE A PERIOD OF LIGHT PRECIPITATION OVER PORTIONS OF OUR
AREA SATURDAY INTO SATURDAY EVENING...PRIMARILY ACROSS OUR SOUTH.
GIVEN THIS...WENT AHEAD WITH LOW POPS ACROSS OUR SOUTH 18Z
SATURDAY THROUGH 06Z SUNDAY ACROSS OUR SOUTH. A SECONDARY MID
LEVEL SHORTWAVE IS THEN EXPECTED TO SWEEP SOUTH/SOUTHEAST ACROSS
PORTIONS OF THE NORTHERN AND CENTRAL PLAINS SUNDAY INTO SUNDAY
NIGHT...WITH ENOUGH DPVA AND MID LEVEL THERMAL ADVECTION FOR LIGHT
PRECIPITATION ACROSS OUR AREA. ALLBLEND RESPONDED BY PRESENTING
~20% POPS TO MUCH OF THE AREA AND THESE POPS WERE LEFT UNCHANGED
FOR THE MOST PART. AN OVERALL LACK IN OMEGA SHOULD THEN PROVIDE
DRY CONDITIONS THROUGH THE REMAINDER OF THE LONG TERM FORECAST
PERIOD.
INCORPORATING THE DRY NAM FORECAST FOR SATURDAY AFTERNOON AND
SATURDAY EVENING...AS WELL AS A BLEND OF THE OPERATIONAL GFS AND
EC...PROVIDES LIQUID PRECIPITATION GENERALLY IN THE 0.01-0.04"
RANGE. SURFACE TEMPERATURES DURING THIS EVENT ARE CURRENTLY
EXPECTED TO RANGE FROM THE UPPER 20S TO AROUND 15...WHICH SUGGESTS
SNOW-WATER RATIOS GENERALLY IN THE 10-20:1 RANGE. THIS PROVIDES
SNOWFALL ACCUMULATION FROM A COUPLE TENTHS OF AN INCH TO PERHAPS
ONE INCH ACROSS OUR SOUTH 18Z SATURDAY THROUGH 06Z SUNDAY.
SNOWFALL RATES ALSO DO NOT LOOK OVERLY IMPRESSIVE SUNDAY INTO
SUNDAY NIGHT WITH PERHAPS ANOTHER INCH OF SNOWFALL ACCUMULATION
POSSIBLE ACROSS MUCH OF THE CWA.
BY FAR THE BIGGEST STORY OF THE LONG TERM FORECAST PERIOD WILL BE
THE VERY COLD TEMPERATURES WHICH LOOK TO INFILTRATE OUR AREA DURING
THE EARLY PART OF NEXT WEEK. WHILE THE COLDEST LOW LEVEL AIRMASS IS
EXPECTED TO RESIDE OVER PORTIONS OF THE UPPER MISSISSIPPI VALLEY
SUNDAY THROUGH TUESDAY...OUR AREA WILL NOT BE SPARED THE AFFECTS
OF THIS FRIGID AIR MASS AS GUIDANCE SUGGESTS SUB-ZERO READINGS
WILL BE REALIZED SUNDAY NIGHT AND MONDAY NIGHT. IN
ADDITION...STRONG LOW LEVEL COLD AIR ADVECTION ON MONDAY WILL
LIKELY KEEP HIGHS IN THE SINGLE DIGITS FOR MOST LOCATIONS ACROSS
THE CWA. THESE COLD TEMPERATURES WILL HELP PROMOTE WIND CHILL
READINGS GENERALLY IN THE -15 TO -25 DEGREE RANGE ACROSS MUCH OF
THE CWA EARLY MONDAY MORNING...WITH WIND CHILL VALUES PERHAPS
APPROACHING -30 ACROSS OUR EXTREME NORTHEAST. WILL GO AHEAD AND
MAINTAIN THE WIND CHILL WORDING IN THE HWO FOR MONDAY MORNING. THE
LOW LEVEL WIND FIELD APPEARS AS THOUGH IT WILL WEAKEN CONSIDERABLY
BY TUESDAY MORNING SO EVEN THOUGH EARLY TUESDAY MORNING LOWS WILL
BE COMPARABLE TO MONDAY...WIND CHILL VALUES ON TUESDAY MORNING DO
NOT APPEAR AS THROUGH THEY WILL DROP BELOW -10 DEGREES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 538 AM CST THU JAN 2 2014
AN UPPER LEVEL JET STREAK NOSING IN FROM THE NORTH IS BRINGING
SOME LIGHT SNOW/FLURRIES TO THE REGION...BUT AT THIS POINT ANY
ACTIVITY IS EXPECTED TO REMAIN NORTH OF THE TERMINAL AND KEPT ANY
MENTION OUT. MAIN UNCERTAINTY FOR THE PERIOD LIES WITH CLOUD COVER
AND POTENTIAL CEILING RESTRICTIONS. THE TERMINAL IS CURRENTLY
ON THE WRN EDGE OF A BAND OF LOWER LEVEL STRATUS...DECIDED TO KEEP
THE PREVAILING CONDITIONS THROUGH MID MORNING VFR...BUT CANT RULE
OUT CEILINGS ARND 2500FT MOVING BACK IN AND HAVE A TEMPO GROUP
GOING. WHILE WINDS ARE CURRENTLY ON THE LIGHT/VARIABLE SIDE...A
FRONTAL BOUNDARY WILL SLIDE THROUGH THE TERMINAL AREA LATER THIS
MORNING...USHERING IN NORTHEASTERLY WINDS...AND THE POTENTIAL FOR
ANOTHER SHOT OF THAT LOWER LEVEL STRATUS. THIS AFTERNOON AND
THROUGH THE END OF THE PERIOD...CEILINGS ARE EXPECTED TO LIFT AND
CLOUD COVER MAY DIMINISH A BIT...SO HAVE VFR CONDITIONS
GOING...BUT CONFIDENCE REMAINS LOW WITH TIMING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...ADO
LONG TERM...BRYANT
AVIATION...ADO
AREA FORECAST DISCUSSION
NWS HASTINGS NE
412 AM CST THU JAN 2 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM CST THU JAN 2 2014
MAIN FORECAST CONCERN FOR THE SHORT TERM PERIOD LIES WITH SOME
LIGHT SNOW CHANCES AND TRICKY HIGH TEMPERATURES FOR TODAY.
QUIET CONDITIONS REMAIN IN PLACE ACROSS THE CWA EARLY THIS
MORNING...AND WE CONTINUE TO SIT UNDER NORTHWESTERLY FLOW IN THE
UPPER LEVELS AS A LARGE AREA OF LOW PRESSURE CONTINUES TO SPIN
OVER ERN CANADA...WITH YESTERDAYS SNOW-PRODUCING DISTURBANCE
MOVING INTO THE MIDWEST...WHILE RIDGING REMAINS OFF THE WEST
COAST. A STOUT ~130KT UPPER LEVEL JET STREAK NOSING IN FROM THE
NORTH BEHIND THE TROUGH AXIS...HELPING DRIVE SOME LIGHT
SNOW/FLURRIES...WITH INCREASED RADAR RETURNS JUST NORTH OF THE
CWA. SKIES ACROSS THE CWA CURRENTLY MOSTLY CLOUDY/OVERCAST THANKS
TO A BAND OF MAINLY LOWER LEVEL STRATUS STRETCHED FROM THE NRN
ROCKIES INTO CENTRAL KS. AT THE SURFACE...HIGH PRESSURE DRAPED
GENERALLY THROUGH THE ERN PORTIONS OF THE CENTRAL PLAINS IS
KEEPING WINDS ON THE LIGHT/VARIABLE SIDE...WITH MORE OF A WESTERLY
COMPONENT DEVELOPING ACROSS WRN LOCATIONS.
THIS MORNING...THAT UPPER LEVEL JET STREAK REMAINS IN THE
AREA...AND WILL CONTINUE TO BRING THE POTENTIAL FOR SOME LIGHT
SNOW/FLURRIES TO MAINLY THE NORTHEASTERN HALF OF THE CWA. WITH
UPSTREAM OBS SHOWING VISIBILITIES DROPPING AT TIMES INTO THE 2-3
MILE RANGE...PERHAPS A FEW AREAS COULD MAYBE PICK UP A TENTH OF AN
INCH OR SO OF SNOW ACCUMULATION...SO HAVE SOME LOW POPS GOING.
OTHERWISE THE REST OF THE SHORT TERM REMAINS DRY. KEPT HIGH SKY
COVER VALUES GOING THIS MORNING...BUT SATELLITE IMAGERY SUGGESTS
THE WRN EDGE OF THAT BAND OF CLOUD COVER ISNT FAR OUTSIDE THE WRN
EDGE OF THE CWA...AND MODELS ARENT IN TOO BAD OF AGREEMENT SHOWING
THE HIGHER CLOUD COVER TRANSITIONING TO MAINLY AFFECT THE
NORTHEASTERN HALF OF THE CWA...WITH MORE SUN POTENTIAL FURTHER
SOUTHWEST.
LOOKING AT TEMPERATURES...HIGHS FOR TODAY ARE TRICKY...AND
CONFIDENCE IS NOT HIGH. WHILE WINDS ARE MAINLY ON THE
LIGHT/VARIABLE TO WESTERLY SIDE CURRENTLY...MODELS SHOW THE CWA
BEING AFFECTED BY A BACKDOOR COLD FRONT SLIDING IN FROM THE
NORTH/NORTHEAST THIS MORNING...AND THE POSITION OF THIS FRONT
THROUGH THE DAY WILL HAVE A BIG IMPACT ON WHAT TEMPS GET TO TODAY.
THERE ARE DIFFERENCES BETWEEN MODELS WITH TIMING/LOCATION. LOOKING
AT MIDDAY...THE 07Z HRRR AND 09Z RAP /THE RAP HAS DONE FAIRLY
WELL THE LAST FEW DAYS WITH HIGHS/ SHOW THE FRONT ROUGHLY ALONG A
BBW TO CNK LINE THROUGH THE CWA...VS OTHER MODELS WHICH FURTHER
WEST BY THEN...CLOSER TO A LBF TO RSL LINE. MAYBE NOT A HUGE
DIFFERENCE...BUT THE SLOWER PROGRESS OF THE BOUNDARY...WITH THE
WESTERLY WINDS AHEAD OF THE FRONT...WOULD ALLOW WRN AND POSSIBLY
CENTRAL PORTIONS OF THE CWA /INCLUDING THE TRI CITIES/ TO REACH
HIGHER TEMPS BEFORE THE EASTERLY WINDS ACCOMPANYING THE FRONT TAKE
OVER AND TEMPS DONT REALLY GO ANYWHERE. THIS LOOKS TO BE THE STORY
WITH NERN PORTIONS OF THE CWA...WHICH WILL COME UNDER THE
INFLUENCE OF THOSE E/NERLY WINDS EARLY ON IN THE DAY. DONT WANT TO
COMPLETELY DISCOUNT OR BUY FULLY INTO WHAT THE RAP/HRRR
SUGGEST...SO HIGHS ARE A BLEND...RANGING FROM ARND 10 DEGREES IN
THE NORTHEAST...TO MID 30S IN THE SW. OVERNIGHT LOWS TONIGHT LOOK
TO FALL BACK INTO THE LOW SINGLE DIGITS EAST TO MID TEENS WEST.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 409 AM CST THU JAN 2 2014
GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC AND SREF-MEAN ALL
SUGGEST A MID LEVEL SHORT WAVE WILL MOVE FROM THE NORTHWESTERN
CONUS...SOUTHEAST INTO PORTIONS OF THE CENTRAL PLAINS FRIDAY INTO
SATURDAY. THE NAM SUGGESTS A NEARLY CONTINUOUS ~70KT MID LEVEL JET
STREAM AXIS WILL EXTEND FROM COLORADO TO THE GREAT LAKES REGION AT
18Z SATURDAY. THE OPERATIONAL GFS AND EC ON THE OTHER HAND BOTH
SUGGEST A BREAK IN THIS MID LEVEL JET AXIS OVER THE CENTRAL PLAINS
WILL ALLOW THE RIGHT-REAR QUADRANT OF A DEPARTING JET STREAK...AND
THE LEFT-FRONT QUADRANT OF AN INCOMING JET STREAK...TO SET UP FROM
WESTERN KANSAS INTO SOUTHEASTERN NEBRASKA AT 18Z SATURDAY. DPVA
AND MID LEVEL THERMAL ADVECTION AHEAD OF THE INCOMING MID LEVEL
SHORTWAVE DO NOT APPEAR OVERLY STRONG AND THE NAM RESPONDS BY
KEEPING OUR AREA DRY THROUGH THE WEEKEND. THE OPERATIONAL GFS AND
EC ON THE OTHER HAND BOTH SUGGEST ENHANCED OMEGA DUE TO DIRECT AND
INDIRECT THERMAL CIRCULATIONS FROM THE AFOREMENTIONED JET STREAKS
WILL PROMOTE A PERIOD OF LIGHT PRECIPITATION OVER PORTIONS OF OUR
AREA SATURDAY INTO SATURDAY EVENING...PRIMARILY ACROSS OUR SOUTH.
GIVEN THIS...WENT AHEAD WITH LOW POPS ACROSS OUR SOUTH 18Z
SATURDAY THROUGH 06Z SUNDAY ACROSS OUR SOUTH. A SECONDARY MID
LEVEL SHORTWAVE IS THEN EXPECTED TO SWEEP SOUTH/SOUTHEAST ACROSS
PORTIONS OF THE NORTHERN AND CENTRAL PLAINS SUNDAY INTO SUNDAY
NIGHT...WITH ENOUGH DPVA AND MID LEVEL THERMAL ADVECTION FOR LIGHT
PRECIPITATION ACROSS OUR AREA. ALLBLEND RESPONDED BY PRESENTING
~20% POPS TO MUCH OF THE AREA AND THESE POPS WERE LEFT UNCHANGED
FOR THE MOST PART. AN OVERALL LACK IN OMEGA SHOULD THEN PROVIDE
DRY CONDITIONS THROUGH THE REMAINDER OF THE LONG TERM FORECAST
PERIOD.
INCORPORATING THE DRY NAM FORECAST FOR SATURDAY AFTERNOON AND
SATURDAY EVENING...AS WELL AS A BLEND OF THE OPERATIONAL GFS AND
EC...PROVIDES LIQUID PRECIPITATION GENERALLY IN THE 0.01-0.04"
RANGE. SURFACE TEMPERATURES DURING THIS EVENT ARE CURRENTLY
EXPECTED TO RANGE FROM THE UPPER 20S TO AROUND 15...WHICH SUGGESTS
SNOW-WATER RATIOS GENERALLY IN THE 10-20:1 RANGE. THIS PROVIDES
SNOWFALL ACCUMULATION FROM A COUPLE TENTHS OF AN INCH TO PERHAPS
ONE INCH ACROSS OUR SOUTH 18Z SATURDAY THROUGH 06Z SUNDAY.
SNOWFALL RATES ALSO DO NOT LOOK OVERLY IMPRESSIVE SUNDAY INTO
SUNDAY NIGHT WITH PERHAPS ANOTHER INCH OF SNOWFALL ACCUMULATION
POSSIBLE ACROSS MUCH OF THE CWA.
BY FAR THE BIGGEST STORY OF THE LONG TERM FORECAST PERIOD WILL BE
THE VERY COLD TEMPERATURES WHICH LOOK TO INFILTRATE OUR AREA DURING
THE EARLY PART OF NEXT WEEK. WHILE THE COLDEST LOW LEVEL AIRMASS IS
EXPECTED TO RESIDE OVER PORTIONS OF THE UPPER MISSISSIPPI VALLEY
SUNDAY THROUGH TUESDAY...OUR AREA WILL NOT BE SPARED THE AFFECTS
OF THIS FRIGID AIR MASS AS GUIDANCE SUGGESTS SUB-ZERO READINGS
WILL BE REALIZED SUNDAY NIGHT AND MONDAY NIGHT. IN
ADDITION...STRONG LOW LEVEL COLD AIR ADVECTION ON MONDAY WILL
LIKELY KEEP HIGHS IN THE SINGLE DIGITS FOR MOST LOCATIONS ACROSS
THE CWA. THESE COLD TEMPERATURES WILL HELP PROMOTE WIND CHILL
READINGS GENERALLY IN THE -15 TO -25 DEGREE RANGE ACROSS MUCH OF
THE CWA EARLY MONDAY MORNING...WITH WIND CHILL VALUES PERHAPS
APPROACHING -30 ACROSS OUR EXTREME NORTHEAST. WILL GO AHEAD AND
MAINTAIN THE WIND CHILL WORDING IN THE HWO FOR MONDAY MORNING. THE
LOW LEVEL WIND FIELD APPEARS AS THOUGH IT WILL WEAKEN CONSIDERABLY
BY TUESDAY MORNING SO EVEN THOUGH EARLY TUESDAY MORNING LOWS WILL
BE COMPARABLE TO MONDAY...WIND CHILL VALUES ON TUESDAY MORNING DO
NOT APPEAR AS THROUGH THEY WILL DROP BELOW -10 DEGREES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1134 PM CST WED JAN 1 2014
PRIMARY FORECAST CONCERN FOR THIS TAF PERIOD LIES WITH CLOUD
COVER. THE NEXT BATCH OF LOWER LEVEL STRATUS HAS MOVED INTO THE
TERMINAL AREA...WITH MODELS SHOWING IT STICKING AROUND FOR A
WHILE. HAVE MVFR CEILINGS GOING INTO THIS AFTERNOON...BUT
CONFIDENCE IN WHEN THOSE CEILINGS WILL LIFT IS NOT HIGH. LOOKING
AT WINDS...SURFACE HIGH PRESSURE SETTLED INTO THE AREA WILL KEEP
WINDS ON THE LIGHT/VARIABLE SIDE THROUGH MID AFTERNOON...BEFORE
E/SERLY WINDS MAKE A RETURN.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...ADO
LONG TERM...BRYANT
AVIATION...ADO
AREA FORECAST DISCUSSION
NWS BUFFALO NY
141 AM EST THU JAN 2 2014
.SYNOPSIS...
A BITTERLY COLD AIRMASS WILL DROP ACROSS THE REGION TONIGHT AND
LINGER THROUGH FRIDAY. A WIDESPREAD AND PROLONGED SNOW EVENT WILL
DEVELOP TONIGHT THROUGH EARLY FRIDAY...ONE THAT WILL BRING
ACCUMULATING SNOWS HEAVIEST TO THE GENESEE VALLEY AND NORTHERN
FINGER LAKES REGION. A NORTHEAST WIND WILL LOWER WIND CHILLS TO
DANGEROUS LEVELS...ESPECIALLY ACROSS THE NORTH COUNTRY WHERE BRUTAL
WIND CHILLS WILL DEVELOP TONIGHT AND TOMORROW NIGHT. A WARMING TREND
IS EXPECTED FOR THE COMING WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
LATEST REGIONAL RADAR IMAGERY IS SHOWING CONSOLIDATION OF THE WARM
FRONTAL SNOW BAND ACROSS THE NIAGARA FRONTIER LATE THIS EVENING EVEN
AS THE SNOW IS TEMPORARILY TAPERING OFF ACROSS THE SOUTHERN TIER.
THE CULPRIT THERE IS LIKELY A DRY SLOT INDUCED BY WEAK SUBSIDENCE
ALOFT...HOWEVER SATELLITE OBS INDICATE ANOTHER SHOT OF MOISTURE
LURKING UPSTREAM ACROSS WESTERN LAKE ERIE THAT SHOULD BRING SNOW
BACK INTO THE WESTERN SOUTHERN TIER A LITTLE AFTER MIDNIGHT...AS
SUPPORTED BY THE LATEST HRRR GUIDANCE.
WITH DEEPENING MOISTURE ACROSS THE REGION...EXPECT LIGHT SNOW TO
PERSIST OVERNIGHT AS A MID-LEVEL CYCLONE MOVES INTO THE OHIO VALLEY
AND IT/S ASSOCIATED WARM FRONTAL BAND REMAINS NEARLY STATIONARY
ACROSS WESTERN/CENTRAL NEW YORK. SNOWFALL RATES GENERALLY IN THE
NEIGHBORHOOD OF A A QUARTER TO A FEW TENTHS PER HOUR SHOULD RESULT
IN A GENERAL 1 TO 3 INCHES ACROSS THE BULK OF THE FORECAST AREA WITH
THE EXCEPTION OF THE NORTH COUNTRY WHERE THE FRONTAL BAND IS NOT
EXPECTED TO ARRIVE UNTIL NEAR DAYBREAK.
THE AFOREMENTIONED WARM FRONTAL BOUNDARY WILL REMAIN STALLED ACROSS
THE FORECAST AREA THROUGHOUT THE DAY ON THURSDAY AS LOW PRESSURE
SLIDES BY TO OUR SOUTH ACROSS PENNSYLVANIA. THIS WILL ALLOW FOR
LIGHT SNOW TO PERSIST ACROSS THE REGION THROUGHOUT THE
DAY...RESULTING IN WIDESPREAD ACCUMULATIONS IN THE 2 TO 4 INCH RANGE
WITH AS MUCH AS SIX INCHES POSSIBLE ACROSS THE HIGHER TERRAIN OF THE
FINGER LAKES AND ALLEGANY COUNTY...CLOSER TO THE EXPECTED LOCATION
OF THE TIGHTEST THERMAL GRADIENT ALOFT. AS THE LOW PASSES TO OUR
SOUTH...NORTHEASTERLY WINDS WILL STRENGTHEN INTO THE 15 TO 20 MPH
RANGE WITH GUSTS AS HIGH AS 35 MPH POSSIBLE NEAR THE LAKE ONTARIO
SHORELINE. THIS WILL RESULT IN THE ADDED DIFFICULTY OF
BLOWING/DRIFTING SNOW...PARTICULARLY TOWARDS LAKE ONTARIO. IN
ADDITION...THE INCREASING WINDS COUPLED WITH INCREASING COLD
ADVECTION THAT WILL KEEP AFTERNOON HIGHS DEPRESSED INTO THE LOW
TEENS TO SINGLE DIGITS WILL PRODUCE DANGEROUS WIND CHILLS IN THAT
COULD DIP AS LOW AS 10 BELOW ZERO AND AS MUCH AS 25 BELOW ZERO
ACROSS THE NORTH COUNTRY.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
THURSDAY EVENING WILL START OFF WITH A MID LEVEL FRONTAL BOUNDARY
ACROSS SOUTHERN NEW YORK. MEANWHILE A SHARP 500 MB TROF APPROACHING
FROM THE UPPER LAKES WILL ENERGIZE A COASTAL LOW FORECAST TO DEVELOP
OFF THE MID ATLANTIC COAST. THE APPROACHING TROF WILL HELP ENHANCE
LIFT...HOWEVER THE FRONTAL BOUNDARY WILL SLIDE SOUTHEAST AT IT GETS
WRAPPED UP IN THE DEVELOPING COASTAL LOW. SYNOPTIC SCALE LIFT WITH
THE UPPER TROF ALONE WILL BE FAIRLY MODEST...WITH MOST LOWER
RESOLUTION GUIDANCE FORECASTING ONLY A TENTH OF AN INCH OF QPF FOR
THURSDAY NIGHT. HOWEVER...A DEEPENING NORTHEAST SURFACE FLOW WILL
LIKELY RESULT IN SOME LAKE ENHANCEMENT. THE NORTHEAST FLOW WOULD
FAVOR AREAS ALONG THE SOUTH SHORE OF LAKE ONTARIO...ESPECIALLY
MONROE AND WAYNE COUNTIES WHERE THERE WILL BE A LONGER FETCH AND A
BIT MORE SYNOPTIC MOISTURE. OFF LAKE ERIE SOME ENHANCEMENT IS
POSSIBLE IN CHAUTAUQUA COUNTY. ALSO...COLDER AIR WITH THE UPPER TROF
WILL PLACE THE BEST LIFT IN A MORE FAVORABLE TEMPERATURE FOR
DENDRITIC CRYSTAL GROWTH. 06Z/12Z RUNS OF THE NAM SUGGEST AMPLE
MOISTURE IN THIS LAYER THROUGH THURSDAY NIGHT...WITH A TEMPORARY
INCREASE IN FLUFF FACTOR LIKELY.
MEANWHILE...WIND CHILLS WILL DROP WELL BELOW ZERO ON THURSDAY NIGHT
AND LAST INTO FRIDAY MORNING. THIS WILL BE DUE TO A BRISK 10 TO 20
MPH NNE FLOW. EVEN WITH LITTLE RADIATIONAL COOLING...OVERNIGHT
TEMPERATURES WILL EASILY DROP TO NEAR ZERO IN MOST LOCATIONS...WITH
10 TO 15 BELOW LIKELY ACROSS THE NORTH COUNTRY. THIS WILL RESULT IN
BITTERLY COLD WIND CHILLS DOWN TO 20 BELOW SOUTH OF LAKE
ONTARIO...AND 30 BELOW ACROSS THE NORTH COUNTRY.
THE COMBINATION OF COLD TEMPERATURES...WIND...AND SNOW WILL HAVE A
SIGNIFICANT IMPACT ON TRAVEL...ESPECIALLY ACROSS EASTERN PORTIONS OF
THE CWA. VERY COLD TEMPERATURES WILL MAKE IT DIFFICULT FOR SALT TO
WORK ON ROADS... LEADING TO DIFFICULT AND VERY SLIPPERY TRAVEL.
THE TROF WILL MOVE EAST OF THE REGION FRIDAY...ALLOWING SURFACE HIGH
PRESSURE TO BUILD IN FROM THE WEST. THIS WILL BRING IN PROGRESSIVELY
DRIER AIR WITH ONLY A SHALLOW LAYER OF MOISTURE. 850MB TEMPERATURES
BELOW -20C WILL LIKELY BE TOO COLD FOR DENDRITES...WITH THE
RESULTING LAKE EFFECT SNOW LIKELY TO HAVE POOR SNOW TO WATER RATIOS.
THESE FACTORS SHOULD LEAD TO GENERALLY LIGHT ADDITIONAL ACCUMULATION
ON FRIDAY. TEMPERATURES WILL ONLY REBOUND SOME...WITH HIGHS IN THE
SINGLE DIGITS SOUTH OF LAKE ONTARIO...AND BELOW ZERO ACROSS THE
NORTH COUNTRY.
ON FRIDAY NIGHT...ANY LINGERING LAKE SNOWS WILL END AS HIGH PRESSURE
CRESTS ACROSS THE REGION. THIS WILL LIKELY BRING THE COLDEST
NON-WIND CHILL TEMPERATURES...WITH LOWS OF MINUS 20 A GOOD
POSSIBILITY IN THE NORTH COUNTRY AND ZERO TO 5 BELOW ELSEWHERE.
SOUTHERLY WINDS WILL PICK UP OVERNIGHT...WHICH WILL LIMIT
RADIATIONAL COOLING AND EVENTUALLY CAUSE TEMPERATURES TO RISE
OVERNIGHT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL SLIDE TO THE EAST OF THE REGION ON SATURDAY...
BRINGING FAIR WEATHER AND WARMER TEMPERATURES TO WESTERN NEW YORK
FOR SATURDAY. A COLD FRONT WILL APPROACH FROM THE WEST ON
SATURDAY...WITH A CHANCE OF SNOW SHOWERS...ESPECIALLY TO THE WEST.
THINGS GET A BIT MORE INTERESTING IN THE SUNDAY AND MONDAY
TIMEFRAME. THERE HAS BEEN A WIDE SPREAD IN MODEL SOLUTIONS...WITH
12Z RUNS OF GFS/GGEM/ECMWF COMING INTO A BIT BETTER AGREEMENT. ALL
THREE NOW FORECAST A SIGNIFICANT WAVE OF LOW PRESSURE RIDING ALONG
THE FRONTAL BOUNDARY. THE GFS IS STILL THE WEAKEST AND
COLDEST...WITH THE ECMWF STRONGEST AND WARM ENOUGH O CHANGE
PRECIPITATION TO RAIN EAST OF ROCHESTER. TAKING A CONSENSUS...EXPECT
SNOW IS THE MORE LIKELY FORM OF PRECIPITATION...WITH THE BEST CHANCE
FOR IT STILL COMING SUNDAY NIGHT INTO MONDAY. DEPENDING ON THE
STRENGTH AND TRACK OF THE LOW...SNOW ACCUMULATIONS COULD BE
SIGNIFICANT. IT IS STILL TOO EARLY TO DETERMINE SPECIFICS...WITH
PLENTY OF OPPORTUNITY FOR FUTURE SHIFTS IN MODEL GUIDANCE.
AFTER THIS...THERE IS GOOD MODEL AGREEMENT THAT ANOTHER SHOT OF VERY
COULD AIR WILL BUILD IN BEHIND WHATEVER LOW DOES DEVELOP. EXPECT
BELOW NORMAL TEMPERATURES AND FAIRLY WINDY CONDITIONS TUESDAY AND
WEDNESDAY. THIS ALSO IS LIKELY TO BRING MORE LAKE EFFECT SNOWS EAST
AND POSSIBLY NORTHEAST OF THE LAKES.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
REGIONAL RADAR CURRENTLY SHOWS A BAND OF LIGHT SNOW CONSOLIDATING
ACROSS THE NIAGARA FRONTIER AND EXTENDING EAST ALONG/NORTH OF THE NYS
THRUWAY. VSBYS WITHIN THIS BAND..THAT ENCOMPASSES
KBUF/KIAG/KROC...WILL REMAIN IFR WITH MVFR CIGS EXPECTED FOR MUCH OF
THE NIGHT AS THE BAND WILL REMAIN NEARLY STATIONARY. MEANWHILE...A
DRY SLOT HAS MOVED OVER THE WESTERN SOUTHERN TIER...BRINGING A BREAK
IN THE SNOWFALL. MESOSCALE MODEL GUIDANCE INDICATES THAT THIS BREAK
AT KJHW MAY LAST AS LATE AS 06-07Z BEFORE ANOTHER SHOT OF MOISTURE
BRINGS LIGHT SNOW BACK ACROSS THE TERMINAL.
MEANWHILE...KART IS STILL VFR AND SHOULD REMAIN SO UNTIL 11Z WHEN
THE BAND PIVOTS NORTHWARDS INTO THE NORTH COUNTRY...BRINGING
MVFR/IFR CONDITIONS. THESE CONDITIONS ARE EXPECTED TO PERSIST FOR
THE BALANCE OF THE TAF PERIOD.
IN ADDITION TO REDUCED VSBYS/CIGS DUE TO THE PRESENCE OF LIGHT
SNOW...FURTHER REDUCTIONS IN VSBYS WILL BE POSSIBLE DURING THE DAY
ON FRIDAY AS NORTHEASTERLY WINDS WILL INCREASE INTO THE 20KT
RANGE...MAKING BLOWING SNOW AN ISSUE ACROSS THE FORECAST AREA.
OUTLOOK...
THURSDAY AND THURSDAY NIGHT...IFR/MVFR WITH SNOW LIKELY.
FRIDAY...IFR/MVFR IN LAKE EFFECT SNOW SHOWERS SOUTHEAST OF THE
LAKES. OTHERWISE MAINLY VFR.
SATURDAY...VFR.
SATURDAY NIGHT AND SUNDAY...MVFR/IFR IN SNOW SHOWERS.
MONDAY...MVFR IN A CHANCE OF SNOW SHOWERS.
&&
.MARINE...
NORTHEASTERLY WINDS WILL FRESHEN TONIGHT AND THURSDAY AND BRING
SMALL CRAFT ADVISORY LEVEL CONDITIONS TO THE LAKES AS WELL AS THE
LOWER NIAGARA RIVER AS LOW PRESSURE APPROACHES THE REGION FROM THE
LOWER OHIO VALLEY. THESE WINDS WILL CONTINUE TO STRENGTHEN THURSDAY
AS THE LOW SLIDES BY TO OUR SOUTH ACROSS PENNSYLVANIA AND EVEN
COLDER AIR WRAPS IN BEHIND THIS LOW. THIS COLD ADVECTION WILL AID IN
KEEPING CONDITIONS ROUGH ON THE LAKES INTO FRIDAY MORNING BEFORE
HIGH PRESSURE MOVES ACROSS THE REGION LATER IN THE DAY...BRINGING A
BRIEF RESPITE BEFORE SOUTHWESTERLIES THEN FRESHEN SATURDAY AS
ANOTHER LOW PRESSURE SYSTEM APPROACHES THE REGION...THIS TIME FROM
NORTHERN ONTARIO. HEAVY FREEZING SPRAY IS LIKELY GIVEN THE
CONDITIONS ON VERY COLD TEMPERATURES...STRONG WINDS AND HIGH
WAVES. A FREEZING SPRAY WARNING WILL REMAIN IN EFFECT THROUGH MID
DAY ON FRIDAY FOR NEARSHORE AND OPEN WATERS OF LAKE ONTARIO AND
NEARSHORE WATERS OF LAKE ERIE.
&&
.CLIMATE...
VERY COLD AIR IS ON THE WAY FOR THE REGION THIS WEEK...WITH THE
COLD AIR PEAKING THURSDAY AND FRIDAY. HIGH TEMPERATURES ON FRIDAY
WILL LIKELY NOT GET OUT OF THE SINGLE NUMBERS ACROSS THE ENTIRE
REGION...AND NOT ABOVE ZERO EAST OF LAKE ONTARIO.
THE LAST TIME BUFFALO DID NOT GET TO 10 DEGREES FOR A DAYTIME HIGH
WAS 1/16/09...AND FOR ROCHESTER 3/6/07. AT WATERTOWN THE LAST TIME
THE HIGH DID NOT GET ABOVE ZERO WAS 1/22/2005.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR NYZ001-002-
006-010>012-019-020-085.
WIND CHILL ADVISORY FROM 4 PM THIS AFTERNOON TO NOON EST
FRIDAY FOR NYZ001>006-010>014-019>021-085.
WIND CHILL WARNING FROM 4 PM THIS AFTERNOON TO NOON EST FRIDAY
FOR NYZ007-008.
WIND CHILL ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NYZ007-
008.
WINTER STORM WARNING UNTIL 6 AM EST FRIDAY FOR NYZ003>005-013-
014-021.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST FRIDAY FOR LEZ040-041.
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST FRIDAY FOR
LEZ040-041.
SMALL CRAFT ADVISORY UNTIL 6 AM EST FRIDAY FOR LOZ030.
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST FRIDAY FOR
LOZ042>045-062>065.
SMALL CRAFT ADVISORY UNTIL 10 AM EST FRIDAY FOR LOZ042>045.
&&
$$
SYNOPSIS...THOMAS
NEAR TERM...WOOD
SHORT TERM...APFFEL
LONG TERM...APFFEL
AVIATION...WOOD
MARINE...THOMAS/WCH/WOOD
CLIMATE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1139 PM EST WED JAN 1 2014
.SYNOPSIS...
A BITTERLY COLD AIRMASS WILL DROP ACROSS THE REGION TONIGHT AND
LINGER THROUGH FRIDAY. A WIDESPREAD AND PROLONGED SNOW EVENT WILL
DEVELOP TONIGHT THROUGH EARLY FRIDAY...ONE THAT WILL BRING
ACCUMULATING SNOWS HEAVIEST TO THE GENESEE VALLEY AND NORTHERN
FINGER LAKES REGION. A NORTHEAST WIND WILL LOWER WIND CHILLS TO
DANGEROUS LEVELS...ESPECIALLY ACROSS THE NORTH COUNTRY WHERE BRUTAL
WIND CHILLS WILL DEVELOP TONIGHT AND TOMORROW NIGHT. A WARMING TREND
IS EXPECTED FOR THE COMING WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
LATEST REGIONAL RADAR IMAGERY IS SHOWING CONSOLIDATION OF THE WARM
FRONTAL SNOW BAND ACROSS THE NIAGARA FRONTIER LATE THIS EVENING EVEN
AS THE SNOW IS TEMPORARILY TAPERING OFF ACROSS THE SOUTHERN TIER.
THE CULPRIT THERE IS LIKELY A DRY SLOT INDUCED BY WEAK SUBSIDENCE
ALOFT...HOWEVER SATELLITE OBS INDICATE ANOTHER SHOT OF MOISTURE
LURKING UPSTREAM ACROSS WESTERN LAKE ERIE THAT SHOULD BRING SNOW
BACK INTO THE WESTERN SOUTHERN TIER A LITTLE AFTER MIDNIGHT...AS
SUPPORTED BY THE LATEST HRRR GUIDANCE.
WITH DEEPENING MOISTURE ACROSS THE REGION...EXPECT LIGHT SNOW TO
PERSIST OVERNIGHT AS A MID-LEVEL CYCLONE MOVES INTO THE OHIO VALLEY
AND IT/S ASSOCIATED WARM FRONTAL BAND REMAINS NEARLY STATIONARY
ACROSS WESTERN/CENTRAL NEW YORK. SNOWFALL RATES GENERALLY IN THE
NEIGHBORHOOD OF A A QUARTER TO A FEW TENTHS PER HOUR SHOULD RESULT
IN A GENERAL 1 TO 3 INCHES ACROSS THE BULK OF THE FORECAST AREA WITH
THE EXCEPTION OF THE NORTH COUNTRY WHERE THE FRONTAL BAND IS NOT
EXPECTED TO ARRIVE UNTIL NEAR DAYBREAK.
THE AFOREMENTIONED WARM FRONTAL BOUNDARY WILL REMAIN STALLED ACROSS
THE FORECAST AREA THROUGHOUT THE DAY ON THURSDAY AS LOW PRESSURE
SLIDES BY TO OUR SOUTH ACROSS PENNSYLVANIA. THIS WILL ALLOW FOR
LIGHT SNOW TO PERSIST ACROSS THE REGION THROUGHOUT THE
DAY...RESULTING IN WIDESPREAD ACCUMULATIONS IN THE 2 TO 4 INCH RANGE
WITH AS MUCH AS SIX INCHES POSSIBLE ACROSS THE HIGHER TERRAIN OF THE
FINGER LAKES AND ALLEGANY COUNTY...CLOSER TO THE EXPECTED LOCATION
OF THE TIGHTEST THERMAL GRADIENT ALOFT. AS THE LOW PASSES TO OUR
SOUTH...NORTHEASTERLY WINDS WILL STRENGTHEN INTO THE 15 TO 20 MPH
RANGE WITH GUSTS AS HIGH AS 35 MPH POSSIBLE NEAR THE LAKE ONTARIO
SHORELINE. THIS WILL RESULT IN THE ADDED DIFFICULTY OF
BLOWING/DRIFTING SNOW...PARTICULARLY TOWARDS LAKE ONTARIO. IN
ADDITION...THE INCREASING WINDS COUPLED WITH INCREASING COLD
ADVECTION THAT WILL KEEP AFTERNOON HIGHS DEPRESSED INTO THE LOW
TEENS TO SINGLE DIGITS WILL PRODUCE DANGEROUS WIND CHILLS IN THAT
COULD DIP AS LOW AS 10 BELOW ZERO AND AS MUCH AS 25 BELOW ZERO
ACROSS THE NORTH COUNTRY.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
THURSDAY EVENING WILL START OFF WITH A MID LEVEL FRONTAL BOUNDARY
ACROSS SOUTHERN NEW YORK. MEANWHILE A SHARP 500 MB TROF APPROACHING
FROM THE UPPER LAKES WILL ENERGIZE A COASTAL LOW FORECAST TO DEVELOP
OFF THE MID ATLANTIC COAST. THE APPROACHING TROF WILL HELP ENHANCE
LIFT...HOWEVER THE FRONTAL BOUNDARY WILL SLIDE SOUTHEAST AT IT GETS
WRAPPED UP IN THE DEVELOPING COASTAL LOW. SYNOPTIC SCALE LIFT WITH
THE UPPER TROF ALONE WILL BE FAIRLY MODEST...WITH MOST LOWER
RESOLUTION GUIDANCE FORECASTING ONLY A TENTH OF AN INCH OF QPF FOR
THURSDAY NIGHT. HOWEVER...A DEEPENING NORTHEAST SURFACE FLOW WILL
LIKELY RESULT IN SOME LAKE ENHANCEMENT. THE NORTHEAST FLOW WOULD
FAVOR AREAS ALONG THE SOUTH SHORE OF LAKE ONTARIO...ESPECIALLY
MONROE AND WAYNE COUNTIES WHERE THERE WILL BE A LONGER FETCH AND A
BIT MORE SYNOPTIC MOISTURE. OFF LAKE ERIE SOME ENHANCEMENT IS
POSSIBLE IN CHAUTAUQUA COUNTY. ALSO...COLDER AIR WITH THE UPPER TROF
WILL PLACE THE BEST LIFT IN A MORE FAVORABLE TEMPERATURE FOR
DENDRITIC CRYSTAL GROWTH. 06Z/12Z RUNS OF THE NAM SUGGEST AMPLE
MOISTURE IN THIS LAYER THROUGH THURSDAY NIGHT...WITH A TEMPORARY
INCREASE IN FLUFF FACTOR LIKELY.
MEANWHILE...WIND CHILLS WILL DROP WELL BELOW ZERO ON THURSDAY NIGHT
AND LAST INTO FRIDAY MORNING. THIS WILL BE DUE TO A BRISK 10 TO 20
MPH NNE FLOW. EVEN WITH LITTLE RADIATIONAL COOLING...OVERNIGHT
TEMPERATURES WILL EASILY DROP TO NEAR ZERO IN MOST LOCATIONS...WITH
10 TO 15 BELOW LIKELY ACROSS THE NORTH COUNTRY. THIS WILL RESULT IN
BITTERLY COLD WIND CHILLS DOWN TO 20 BELOW SOUTH OF LAKE
ONTARIO...AND 30 BELOW ACROSS THE NORTH COUNTRY.
THE COMBINATION OF COLD TEMPERATURES...WIND...AND SNOW WILL HAVE A
SIGNIFICANT IMPACT ON TRAVEL...ESPECIALLY ACROSS EASTERN PORTIONS OF
THE CWA. VERY COLD TEMPERATURES WILL MAKE IT DIFFICULT FOR SALT TO
WORK ON ROADS... LEADING TO DIFFICULT AND VERY SLIPPERY TRAVEL.
THE TROF WILL MOVE EAST OF THE REGION FRIDAY...ALLOWING SURFACE HIGH
PRESSURE TO BUILD IN FROM THE WEST. THIS WILL BRING IN PROGRESSIVELY
DRIER AIR WITH ONLY A SHALLOW LAYER OF MOISTURE. 850MB TEMPERATURES
BELOW -20C WILL LIKELY BE TOO COLD FOR DENDRITES...WITH THE
RESULTING LAKE EFFECT SNOW LIKELY TO HAVE POOR SNOW TO WATER RATIOS.
THESE FACTORS SHOULD LEAD TO GENERALLY LIGHT ADDITIONAL ACCUMULATION
ON FRIDAY. TEMPERATURES WILL ONLY REBOUND SOME...WITH HIGHS IN THE
SINGLE DIGITS SOUTH OF LAKE ONTARIO...AND BELOW ZERO ACROSS THE
NORTH COUNTRY.
ON FRIDAY NIGHT...ANY LINGERING LAKE SNOWS WILL END AS HIGH PRESSURE
CRESTS ACROSS THE REGION. THIS WILL LIKELY BRING THE COLDEST
NON-WIND CHILL TEMPERATURES...WITH LOWS OF MINUS 20 A GOOD
POSSIBILITY IN THE NORTH COUNTRY AND ZERO TO 5 BELOW ELSEWHERE.
SOUTHERLY WINDS WILL PICK UP OVERNIGHT...WHICH WILL LIMIT
RADIATIONAL COOLING AND EVENTUALLY CAUSE TEMPERATURES TO RISE
OVERNIGHT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL SLIDE TO THE EAST OF THE REGION ON SATURDAY...
BRINGING FAIR WEATHER AND WARMER TEMPERATURES TO WESTERN NEW YORK
FOR SATURDAY. A COLD FRONT WILL APPROACH FROM THE WEST ON
SATURDAY...WITH A CHANCE OF SNOW SHOWERS...ESPECIALLY TO THE WEST.
THINGS GET A BIT MORE INTERESTING IN THE SUNDAY AND MONDAY
TIMEFRAME. THERE HAS BEEN A WIDE SPREAD IN MODEL SOLUTIONS...WITH
12Z RUNS OF GFS/GGEM/ECMWF COMING INTO A BIT BETTER AGREEMENT. ALL
THREE NOW FORECAST A SIGNIFICANT WAVE OF LOW PRESSURE RIDING ALONG
THE FRONTAL BOUNDARY. THE GFS IS STILL THE WEAKEST AND
COLDEST...WITH THE ECMWF STRONGEST AND WARM ENOUGH O CHANGE
PRECIPITATION TO RAIN EAST OF ROCHESTER. TAKING A CONSENSUS...EXPECT
SNOW IS THE MORE LIKELY FORM OF PRECIPITATION...WITH THE BEST CHANCE
FOR IT STILL COMING SUNDAY NIGHT INTO MONDAY. DEPENDING ON THE
STRENGTH AND TRACK OF THE LOW...SNOW ACCUMULATIONS COULD BE
SIGNIFICANT. IT IS STILL TOO EARLY TO DETERMINE SPECIFICS...WITH
PLENTY OF OPPORTUNITY FOR FUTURE SHIFTS IN MODEL GUIDANCE.
AFTER THIS...THERE IS GOOD MODEL AGREEMENT THAT ANOTHER SHOT OF VERY
COULD AIR WILL BUILD IN BEHIND WHATEVER LOW DOES DEVELOP. EXPECT
BELOW NORMAL TEMPERATURES AND FAIRLY WINDY CONDITIONS TUESDAY AND
WEDNESDAY. THIS ALSO IS LIKELY TO BRING MORE LAKE EFFECT SNOWS EAST
AND POSSIBLY NORTHEAST OF THE LAKES.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
REGIONAL RADAR CURRENTLY SHOWS A BAND OF LIGHT SNOW CONSOLIDATING
ACROSS THE NIAGARA FRONTIER AND EXTENDING EAST ALONG/NORTH OF THE NYS
THRUWAY. VSBYS WITHIN THIS BAND..THAT ENCOMPASSES
KBUF/KIAG/KROC...WILL REMAIN IFR WITH MVFR CIGS EXPECTED FOR MUCH OF
THE NIGHT AS THE BAND WILL REMAIN NEARLY STATIONARY. MEANWHILE...A
DRY SLOT HAS MOVED OVER THE WESTERN SOUTHERN TIER...BRINGING A BREAK
IN THE SNOWFALL. MESOSCALE MODEL GUIDANCE INDICATES THAT THIS BREAK
AT KJHW MAY LAST AS LATE AS 06-07Z BEFORE ANOTHER SHOT OF MOISTURE
BRINGS LIGHT SNOW BACK ACROSS THE TERMINAL.
MEANWHILE...KART IS STILL VFR AND SHOULD REMAIN SO UNTIL 11Z WHEN
THE BAND PIVOTS NORTHWARDS INTO THE NORTH COUNTRY...BRINGING
MVFR/IFR CONDITIONS. THESE CONDITIONS ARE EXPECTED TO PERSIST FOR
THE BALANCE OF THE TAF PERIOD.
IN ADDITION TO REDUCED VSBYS/CIGS DUE TO THE PRESENCE OF LIGHT
SNOW...FURTHER REDUCTIONS IN VSBYS WILL BE POSSIBLE DURING THE DAY
ON FRIDAY AS NORTHEASTERLY WINDS WILL INCREASE INTO THE 20KT
RANGE...MAKING BLOWING SNOW AN ISSUE ACROSS THE FORECAST AREA.
OUTLOOK...
THURSDAY AND THURSDAY NIGHT...IFR/MVFR WITH SNOW LIKELY.
FRIDAY...IFR/MVFR IN LAKE EFFECT SNOW SHOWERS SOUTHEAST OF THE
LAKES. OTHERWISE MAINLY VFR.
SATURDAY...VFR.
SATURDAY NIGHT AND SUNDAY...MVFR/IFR IN SNOW SHOWERS.
MONDAY...MVFR IN A CHANCE OF SNOW SHOWERS.
&&
.MARINE...
NORTHEASTERLY WINDS WILL FRESHEN TONIGHT AND THURSDAY AND BRING
SMALL CRAFT ADVISORY LEVEL CONDITIONS TO THE LAKES AS WELL AS THE
LOWER NIAGARA RIVER AS LOW PRESSURE APPROACHES THE REGION FROM THE
LOWER OHIO VALLEY. THESE WINDS WILL CONTINUE TO STRENGTHEN THURSDAY
AS THE LOW SLIDES BY TO OUR SOUTH ACROSS PENNSYLVANIA AND EVEN
COLDER AIR WRAPS IN BEHIND THIS LOW. THIS COLD ADVECTION WILL AID IN
KEEPING CONDITIONS ROUGH ON THE LAKES INTO FRIDAY MORNING BEFORE
HIGH PRESSURE MOVES ACROSS THE REGION LATER IN THE DAY...BRINGING A
BRIEF RESPITE BEFORE SOUTHWESTERLIES THEN FRESHEN SATURDAY AS
ANOTHER LOW PRESSURE SYSTEM APPROACHES THE REGION...THIS TIME FROM
NORTHERN ONTARIO.
&&
.CLIMATE...
VERY COLD AIR IS ON THE WAY FOR THE REGION THIS WEEK...WITH THE
COLD AIR PEAKING THURSDAY AND FRIDAY. HIGH TEMPERATURES ON FRIDAY
WILL LIKELY NOT GET OUT OF THE SINGLE NUMBERS ACROSS THE ENTIRE
REGION...AND NOT ABOVE ZERO EAST OF LAKE ONTARIO.
THE LAST TIME BUFFALO DID NOT GET TO 10 DEGREES FOR A DAYTIME HIGH
WAS 1/16/09...AND FOR ROCHESTER 3/6/07. AT WATERTOWN THE LAST TIME
THE HIGH DID NOT GET ABOVE ZERO WAS 1/22/2005.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WIND CHILL WARNING FROM 4 PM THURSDAY TO NOON EST FRIDAY FOR
NYZ007-008.
WIND CHILL ADVISORY UNTIL 4 PM EST THURSDAY FOR NYZ007-008.
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR NYZ001-002-
006-010>012-019-020-085.
WIND CHILL ADVISORY FROM 4 PM THURSDAY TO NOON EST FRIDAY FOR
NYZ001>006-010>014-019>021-085.
WINTER STORM WARNING UNTIL 6 AM EST FRIDAY FOR NYZ003>005-013-
014-021.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST FRIDAY FOR LEZ040-041.
SMALL CRAFT ADVISORY UNTIL 6 AM EST FRIDAY FOR LOZ030.
SMALL CRAFT ADVISORY UNTIL 10 AM EST FRIDAY FOR LOZ042>045.
&&
$$
SYNOPSIS...THOMAS
NEAR TERM...WOOD
SHORT TERM...APFFEL
LONG TERM...APFFEL
AVIATION...WOOD
MARINE...THOMAS/WOOD
CLIMATE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS RALEIGH NC
644 PM EST FRI JAN 3 2014
.SYNOPSIS...ARCTIC AIR OVER THE AREA PERSISTS THROUGH SATURDAY
MORNING. THE AIR MASS WILL WARM AND MOISTEN SUNDAY AS LOW PRESSURE
MOVES INTO THE REGION FROM THE SOUTHWEST. ANOTHER EVEN COLDER SURGE
OF HIGH PRESSURE ARRIVES EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 640 PM FRIDAY...
A NOTICEABLE MID-LEVEL SHORTWAVE WAS MOVING EAST ALONG THE BORDER OF
TENNESSEE AND KENTUCKY EARLY IN THE EVENING. THE LATEST RAP...WHILE
LIKELY JUST A BIT SLOW WITH ITS EASTWARD PROGRESS...SEEMED TO HAVE A
GOOD HANDLE ON THE TRACK OF THE WAVE...TAKING IT ALONG OR JUST NORTH
OF THE VIRGINIA BORDER OVERNIGHT. EARLIER INFRARED SATELLITE IMAGES
SHOWED SCATTERED CLOUDS ASSOCIATED WITH THE WAVE...BUT AS THE RAP
HAS FORECAST DURING THE NIGHT...THE MID-LEVEL MOISTURE DIMINISHES AS
THE WAVE MOVES EAST AND THE LATEST INFRARED IMAGE OR TWO HAS SHOWN
THE CLOUDS DECREASING. NAM AND GFS BUFR SOUNDINGS DO MOISTEN THE MID-
LEVELS LATE TONIGHT BUT THE HRRR WRF AND CANADIAN CLOUD COVER MODELS
SHOW NO CLOUDS IN THEIR FORECASTS...SO ASIDE FROM MAYBE A FEW MID-
LEVEL CLOUDS ESPECIALLY OVER THE NORTHERN HALF OF CENTRAL NORTH
CAROLINA OVERNIGHT CLEAR SKIES SHOULD PREVAIL. WINDS HAVE LIGHTENED
AND WITH THE MAINLY CLEAR SKY...WINDS UNDER 10 MPH...AND DRY AIR
WITH SURFACE DEW POINTS IN THE SINGLE DIGITS TO THE TEENS...WILL
MAINTAIN THE OVERNIGHT LOW FORECAST WHICH IS AT THE LOWER END OF
GUIDANCE...IN THE TEENS ACROSS CENTRAL NORTH CAROLINA. WITH THE
RELATIVELY LIGHT WIND...THE MINIMUM APPARENT TEMPERATURE OVERNIGHT
GENERALLY WILL BE IN THE TEENS AS WELL.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
AS OF 640 PM FRIDAY...
SATURDAY WILL BE DRY AS HIGH PRESSURE MOVES OVERHEAD AND EVENTUALLY
PUSHES EASTWARD AND OUT TO SEA. THIS WILL CAUSE THE DEVELOPMENT OF
WEAK SOUTHERLY RETURN FLOW AROUND THE BACK SIDE OF THE HIGH AND WILL
HELP MAX TEMPERATURES TO RECOVER ON SATURDAY...AT LEAST INTO THE LOW
TO MIDDLE 40S NW TO SE. WITH THAT RETURN FLOW WILL COME THE
DEVELOPMENT OF SOME CLOUDS LATER IN THE AFTERNOON FROM THE SOUTH AS
MOISTURE FROM THE SOUTHWEST ATLANTIC GETS PULLED ASHORE. THE LATEST
RAP SHOWS AN INCREASE IN 925MB MOISTURE AS EARLY AS 15Z TOWARD KFAY
AND KCTZ...AND THE CANADIAN CLOUD COVER MODEL DOES HINT AT A FEW
CLOUDS FOR A PERIOD MID-MORNING OR SO WHICH MAY OF THE LOWER VARIETY
IN THOSE AREAS AS SURFACE PRESSURES SLOWLY START TO FALL AND THE LOW-
LEVEL WINDS VEER. STILL...MORE OF THE CLOUDS SHOULD DEVELOP LATER IN
THE DAY.
BY SATURDAY EVENING THE 1033 MB HIGH SETS UP OFF OF THE MID ATLANTIC
COAST AND A WEAK IN-SITU CAD AND ASSOCIATED WEDGE WILL SET UP ACROSS
THE FOOTHILLS AND THE NORTHWEST PIEDMONT. FAIRLY DECENT ISENTROPIC
LIFT IS DEPICTED IN THE NAM ON THE 290K AND 295K SURFACES WITH
RELATIVE HUMIDITIES NEAR SATURATION BY 6Z SUNDAY MORNING. PRETTY
HIGH CONFIDENCE IN A FEW HUNDREDTHS OF AN INCH OF PRECIPITATION
ACROSS THE NORTHWEST PIEDMONT. THE QUESTION WILL BE IF ANY OF IT
WILL BE FREEZING RAIN OR NOT. TEMPERATURES IN THE NAM...GFS...AND
SREF SUITE ALL HOVER AT OR JUST ABOVE FREEZING BETWEEN ROUGHLY 3 AND
15 Z. MEANWHILE THE WETBULB TEMPERATURE IS HOVERING NEAR OR JUST
BELOW FREEZING AT THE SAME TIME. IF ENOUGH PRECIPITATION OCCURS IT
IS PLAUSIBLE THAT COULD BRING THE TEMPERATURE DOWN BELOW FREEZING
FOR A FEW HOURS...WITH THE SWEET SPOT BETWEEN 9 AND 12Z. THAT BEING
SAID CONFIDENCE IN THIS IS MEDIUM AT BEST AND ANY FREEZING RAIN THAT
DOES OCCUR WILL BE LIMITED TO THE TRIAD AND A COUPLE HUNDREDTHS OF
AN INCH OF ACCUMULATION AT THE MOST...MAINLY ON BRIDGES AND
OVERPASSES AND OTHER ELEVATED SURFACES. CANT RULE OUT A FEW ICY
SPOTS ON ROADWAYS BUT HAVE LOWER CONFIDENCE IN THIS. BOTTOM LINE IS
A NUISANCE LOW IMPACT EVENT THAT WILL END AS SOON AS TEMPERATURES
RECOVER AFTER SUNRISE. LOWS SUNDAY NIGHT WILL RANGE FROM THE LOW TO
MIDDLE 30S NW TO SE. -ELLIS/DJF
THE EARLY MORNING RAIN AND OR FREEZING RAIN OVER THE WESTERN
PIEDMONT IS FORECAST TO MOVE OFF TO THE NORTH BY MIDDAY
SUNDAY...MOST LIKELY LEAVING AN IN-SITU OVER THE WESTERN HALF OF THE
CWA. MODELS DO NOT SHOW MUCH QPF DURING THE AFTERNOON...BUT WITH A
STEADY SOUTHWESTERLY WIND OVER THE COLD DOME...EXPECT THERE TO BE
SOME LIGHT RAIN AND DRIZZLE THAT CONTINUES. MEANWHILE...WARM
ADVECTION WILL STRENGTHEN AND HEIGHTS ALOFT WILL BEGIN TO FALL AS A
POWERFUL FRONTAL SYSTEM APPROACHES FROM THE WEST. MODELS SHOW A
WEAK SURFACE WAVE OR LOW DEVELOPING ALONG THE SC COAST AND TRACKING
NORTH TO EVENTUALLY MERGE WITH THE PARENT LOW OF THE APPROACHING
SYSTEM. EASTERN AREAS MAY SEE A FEW WARM ADVECTION SHOWERS DURING
THE AFTERNOON AND EVENING. TEMPS WILL VARY WIDELY FROM LOWER 40S IN
THE WEST TO LOWER 60S IN THE EAST.
LATER SUNDAY NIGHT...THE AFOREMENTIONED COLD FRONT WILL CROSS THE
AREA WITH A BAND OF SHOWERS AND POSSIBLY SOME STRONG WIND GUSTS DUE
TO THE STRONG GRADIENT ACCOMPANYING THE FRONT. MODELS HAVE SLOWED A
LITTLE ON THE TIMING OF THE FRONT...AND MORE IMPORTANTLY THE BLAST
OF COLD AIR TO FOLLOW AS THICKNESSES CRASH FROM 1360M SUNDAY TO
POTENTIALLY AS LOW AS 1220M BY TUESDAY MORNING. BASED ON CURRENT
TRENDS... TEMPS IN THE 40-60 RANGE ARE LIKELY TO HOLD THROUGH SUNDAY
EVENING...WITH HIGHS OCCURRING JUST AFTER MIDNIGHT... THEN PLUMMET
THROUGH SUNRISE AND RISE VERY LITTLE IF AT ALL ON MONDAY.
THUS...TEMPS DURING THE DAY MONDAY WILL BE IN THE LOWER 30S WEST TO
UPPER 40S EAST. WINDS WILL BE GUSTY...AROUND 20-25MPH...WHICH WILL
CAUSE WIND CHILLS TO STAY IN THE 20S IN THE WEST. -SMITH
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 315 PM FRIDAY...
THE COLD REALLY SETS IN MONDAY NIGHT AS A BITTER ARCTIC HIGH BUILDS
IN FROM THE WEST. LOCAL THICKNESS CLIMATOLOGY SUGGESTS THAT READINGS
IN THE SINGLE DIGITS ARE QUITE POSSIBLE BASED ON THICKNESSES
APPROACHING 1220M. THE SURFACE HIGH ASSOCIATED WITH THIS COLD
AIRMASS WILL STILL BE TO OUR SOUTHWEST OVER THE DEEP SOUTH...SO A
LIGHT WIND MAY NOT ALLOW FOR COMPLETELY OPTIMAL COOLING.
STILL...NWP GUIDANCE IS IN REMARKABLY GOOD AGREEMENT...AND AS
BEEN...WITH STATISTICAL GUIDANCE ALSO COMING INTO AGREEMENT.
CONFIDENCE IS HIGHS ON LOWS IN THE TEENS EVERYWHERE AND IS
INCREASING ON VALUES IN THE SINGLE DIGITS FOR MANY AREAS OVER THE
WESTERN PIEDMONT. GUSTY WINDS ON MONDAY WILL WEAKEN BUT ITS
POSSIBLE THAT WIND CHILL VALUES MAY WINK BELOW ZERO OVERNIGHT AND A
WIND CHILL ADVISORY IS POSSIBLE. HIGHS TUESDAY WILL REMAIN COLD AND
STRUGGLE TO CLIMB THROUGH THE 20S. (SEE CLIMATE SECTION BELOW)
BEYOND TUESDAY...A SLOW WARMING TREND BACK TOWARD NORMAL IS EXPECTED
AS A MORE ZONAL FLOW BEGINS TO DEVELOP. ANOTHER WAVE IS EXPECTED TO
RACE EAST BY THE END OF THE WEEK...THOUGH THE GFS AND ECMWF VARY ON
THE TIMING (GFS FASTER). IN EITHER SCENARIO...A COASTAL LOW AND
POTENTIAL COLD AIR DAMMING SETUP WOULD DEVELOP. CONFIDENCE IN THIS
IS LOW AT THIS TIME..HOWEVER.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 630 PM FRIDAY...
24 HOUR TAF PERIOD: HIGH CONFIDENCE OF VFR CONDITIONS THROUGH THE
END OF THE TAF PERIOD. HIGH PRESSURE WILL BUILD OVERHEAD DURING THE
OVERNIGHT HOURS AND WILL RESULT IN MOSTLY CLEAR SKIES AND LIGHT
WINDS. EXPECT WINDS TO VEER TO SOUTH-SOUTHEASTERLY ON SATURDAY BUT
SHOULD REMAIN RELATIVELY LIGHT...AROUND 5 KTS...THROUGHOUT THE DAY.
GIVEN THE DRY AIR IN PLACE...DO NOT EXPECT ANY SUB-VFR CIGS OR
VISBYS...HOWEVER A FEW LOW CLOUDS MAY DEVELOP ACROSS THE FAR
SOUTHEAST SATURDAY MORNING. THESE FEW TO SCT LOW CLOUDS MAY SPREAD
ACROSS THE AREA TOWARD THE END OF THE 24 HOUR PERIOD...BUT WILL KEEP
MENTION OUT FOR NOW. -KC
LONG TERM: THERE WILL BE A CHANCE FOR SOME VERY BRIEF FREEZING RAIN
AT KINT AND KGSO EARLY SUNDAY MORNING FOR AN HOUR OR TWO SOMETIME
BETWEEN 6 AND 12Z. CONFIDENCE IN THIS OCCURRING IS LOW AND EVEN IF
IT DOES...IMPACTS WILL BE LOW AND ACCUMULATIONS WILL BE A HUNDREDTH
OF AN INCH OR LESS...MAINLY ON ELEVATED SURFACES. RAIN CHANCES WILL
INCREASE ON SUNDAY AND CONTINUE THROUGH MONDAY WITH THE NEXT FRONTAL
SYSTEM BEFORE CLEARING OUT ON MONDAY. -ELLIS
&&
.CLIMATE...
RECORD MIN TEMPS FOR JANUARY 7TH
RDU 15 1988
GSO 14 1988
FAY 13 1959
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF
SHORT TERM...ELLIS/DJF/SMITH
LONG TERM...SMITH
AVIATION...KC/ELLIS
CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
642 PM EST FRI JAN 3 2014
.SYNOPSIS...ARCTIC AIR OVER THE AREA PERSISTS THROUGH SATURDAY
MORNING. THE AIR MASS WILL WARM AND MOISTEN SUNDAY AS LOW PRESSURE
MOVES INTO THE REGION FROM THE SOUTHWEST. ANOTHER EVEN COLDER SURGE
OF HIGH PRESSURE ARRIVES EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 640 PM FRIDAY...
A NOTICEABLE MID-LEVEL SHORTWAVE WAS MOVING EAST ALONG THE BORDER OF
TENNESSEE AND KENTUCKY EARLY IN THE EVENING. THE LATEST RAP...WHILE
LIKELY JUST A BIT SLOW WITH ITS EASTWARD PROGRESS...SEEMED TO HAVE A
GOOD HANDLE ON THE TRACK OF THE WAVE...TAKING IT ALONG OR JUST NORTH
OF THE VIRGINIA BORDER OVERNIGHT. EARLIER INFRARED SATELLITE IMAGES
SHOWED SCATTERED CLOUDS ASSOCIATED WITH THE WAVE...BUT AS THE RAP
HAS FORECAST DURING THE NIGHT...THE MID-LEVEL MOISTURE DIMINISHES AS
THE WAVE MOVES EAST AND THE LATEST INFRARED IMAGE OR TWO HAS SHOWN
THE CLOUDS DECREASING. NAM AND GFS BUFR SOUNDINGS DO MOISTEN THE MID-
LEVELS LATE TONIGHT BUT THE HRRR WRF AND CANADIAN CLOUD COVER MODELS
SHOW NO CLOUDS IN THEIR FORECASTS...SO ASIDE FROM MAYBE A FEW MID-
LEVEL CLOUDS ESPECIALLY OVER THE NORTHERN HALF OF CENTRAL NORTH
CAROLINA OVERNIGHT CLEAR SKIES SHOULD PREVAIL. WINDS HAVE LIGHTENED
AND WITH THE MAINLY CLEAR SKY...WINDS UNDER 10 MPH...AND DRY AIR
WITH SURFACE DEW POINTS IN THE SINGLE DIGITS TO THE TEENS...WILL
MAINTAIN THE OVERNIGHT LOW FORECAST WHICH IS AT THE LOWER END OF
GUIDANCE...IN THE TEENS ACROSS CENTRAL NORTH CAROLINA. WITH THE
RELATIVELY LIGHT WIND...THE MINIMUM APPARENT TEMPERATURE OVERNIGHT
GENERALLY WILL BE IN THE TEENS AS WELL.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
AS OF 640 PM FRIDAY...
SATURDAY WILL BE DRY AS HIGH PRESSURE MOVES OVERHEAD AND EVENTUALLY
PUSHES EASTWARD AND OUT TO SEA. THIS WILL CAUSE THE DEVELOPMENT OF
WEAK SOUTHERLY RETURN FLOW AROUND THE BACK SIDE OF THE HIGH AND WILL
HELP MAX TEMPERATURES TO RECOVER ON SATURDAY...AT LEAST INTO THE LOW
TO MIDDLE 40S NW TO SE. WITH THAT RETURN FLOW WILL COME THE
DEVELOPMENT OF SOME CLOUDS LATER IN THE AFTERNOON FROM THE SOUTH AS
MOISTURE FROM THE SOUTHWEST ATLANTIC GETS PULLED ASHORE. THE LATEST
RAP SHOWS AN INCREASE IN 925MB MOISTURE AS EARLY AS 15Z TOWARD KFAY
AND KCTZ...AND THE CANADIAN CLOUD COVER MODEL DOES HINT AT A FEW
CLOUDS FOR A PERIOD MID-MORNING OR SO WHICH MAY OF THE LOWER VARIETY
IN THOSE AREAS AS SURFACE PRESSURES SLOWLY START TO FALL AND THE LOW-
LEVEL WINDS VEER. STILL...MORE OF THE CLOUDS SHOULD DEVELOP LATER IN
THE DAY.
BY SATURDAY EVENING THE 1033 MB HIGH SETS UP OFF OF THE MID ATLANTIC
COAST AND A WEAK IN-SITU CAD AND ASSOCIATED WEDGE WILL SET UP ACROSS
THE FOOTHILLS AND THE NORTHWEST PIEDMONT. FAIRLY DECENT ISENTROPIC
LIFT IS DEPICTED IN THE NAM ON THE 290K AND 295K SURFACES WITH
RELATIVE HUMIDITIES NEAR SATURATION BY 6Z SUNDAY MORNING. PRETTY
HIGH CONFIDENCE IN A FEW HUNDREDTHS OF AN INCH OF PRECIPITATION
ACROSS THE NORTHWEST PIEDMONT. THE QUESTION WILL BE IF ANY OF IT
WILL BE FREEZING RAIN OR NOT. TEMPERATURES IN THE NAM...GFS...AND
SREF SUITE ALL HOVER AT OR JUST ABOVE FREEZING BETWEEN ROUGHLY 3 AND
15 Z. MEANWHILE THE WETBULB TEMPERATURE IS HOVERING NEAR OR JUST
BELOW FREEZING AT THE SAME TIME. IF ENOUGH PRECIPITATION OCCURS IT
IS PLAUSIBLE THAT COULD BRING THE TEMPERATURE DOWN BELOW FREEZING
FOR A FEW HOURS...WITH THE SWEET SPOT BETWEEN 9 AND 12Z. THAT BEING
SAID CONFIDENCE IN THIS IS MEDIUM AT BEST AND ANY FREEZING RAIN THAT
DOES OCCUR WILL BE LIMITED TO THE TRIAD AND A COUPLE HUNDREDTHS OF
AN INCH OF ACCUMULATION AT THE MOST...MAINLY ON BRIDGES AND
OVERPASSES AND OTHER ELEVATED SURFACES. CANT RULE OUT A FEW ICY
SPOTS ON ROADWAYS BUT HAVE LOWER CONFIDENCE IN THIS. BOTTOM LINE IS
A NUISANCE LOW IMPACT EVENT THAT WILL END AS SOON AS TEMPERATURES
RECOVER AFTER SUNRISE. LOWS SUNDAY NIGHT WILL RANGE FROM THE LOW TO
MIDDLE 30S NW TO SE. -ELLIS/DJF
THE EARLY MORNING RAIN AND OR FREEZING RAIN OVER THE WESTERN
PIEDMONT IS FORECAST TO MOVE OFF TO THE NORTH BY MIDDAY
SUNDAY...MOST LIKELY LEAVING AN IN-SITU OVER THE WESTERN HALF OF THE
CWA. MODELS DO NOT SHOW MUCH QPF DURING THE AFTERNOON...BUT WITH A
STEADY SOUTHWESTERLY WIND OVER THE COLD DOME...EXPECT THERE TO BE
SOME LIGHT RAIN AND DRIZZLE THAT CONTINUES. MEANWHILE...WARM
ADVECTION WILL STRENGTHEN AND HEIGHTS ALOFT WILL BEGIN TO FALL AS A
POWERFUL FRONTAL SYSTEM APPROACHES FROM THE WEST. MODELS SHOW A
WEAK SURFACE WAVE OR LOW DEVELOPING ALONG THE SC COAST AND TRACKING
NORTH TO EVENTUALLY MERGE WITH THE PARENT LOW OF THE APPROACHING
SYSTEM. EASTERN AREAS MAY SEE A FEW WARM ADVECTION SHOWERS DURING
THE AFTERNOON AND EVENING. TEMPS WILL VARY WIDELY FROM LOWER 40S IN
THE WEST TO LOWER 60S IN THE EAST.
LATER SUNDAY NIGHT...THE AFOREMENTIONED COLD FRONT WILL CROSS THE
AREA WITH A BAND OF SHOWERS AND POSSIBLY SOME STRONG WIND GUSTS DUE
TO THE STRONG GRADIENT ACCOMPANYING THE FRONT. MODELS HAVE SLOWED A
LITTLE ON THE TIMING OF THE FRONT...AND MORE IMPORTANTLY THE BLAST
OF COLD AIR TO FOLLOW AS THICKNESSES CRASH FROM 1360M SUNDAY TO
POTENTIALLY AS LOW AS 1220M BY TUESDAY MORNING. BASED ON CURRENT
TRENDS... TEMPS IN THE 40-60 RANGE ARE LIKELY TO HOLD THROUGH SUNDAY
EVENING...WITH HIGHS OCCURRING JUST AFTER MIDNIGHT... THEN PLUMMET
THROUGH SUNRISE AND RISE VERY LITTLE IF AT ALL ON MONDAY.
THUS...TEMPS DURING THE DAY MONDAY WILL BE IN THE LOWER 30S WEST TO
UPPER 40S EAST. WINDS WILL BE GUSTY...AROUND 20-25MPH...WHICH WILL
CAUSE WIND CHILLS TO STAY IN THE 20S IN THE WEST. -SMITH
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 315 PM FRIDAY...
THE COLD REALLY SETS IN MONDAY NIGHT AS A BITTER ARCTIC HIGH BUILDS
IN FROM THE WEST. LOCAL THICKNESS CLIMATOLOGY SUGGESTS THAT READINGS
IN THE SINGLE DIGITS ARE QUITE POSSIBLE BASED ON THICKNESSES
APPROACHING 1220M. THE SURFACE HIGH ASSOCIATED WITH THIS COLD
AIRMASS WILL STILL BE TO OUR SOUTHWEST OVER THE DEEP SOUTH...SO A
LIGHT WIND MAY NOT ALLOW FOR COMPLETELY OPTIMAL COOLING.
STILL...NWP GUIDANCE IS IN REMARKABLY GOOD AGREEMENT...AND AS
BEEN...WITH STATISTICAL GUIDANCE ALSO COMING INTO AGREEMENT.
CONFIDENCE IS HIGHS ON LOWS IN THE TEENS EVERYWHERE AND IS
INCREASING ON VALUES IN THE SINGLE DIGITS FOR MANY AREAS OVER THE
WESTERN PIEDMONT. GUSTY WINDS ON MONDAY WILL WEAKEN BUT ITS
POSSIBLE THAT WIND CHILL VALUES MAY WINK BELOW ZERO OVERNIGHT AND A
WIND CHILL ADVISORY IS POSSIBLE. HIGHS TUESDAY WILL REMAIN COLD AND
STRUGGLE TO CLIMB THROUGH THE 20S. (SEE CLIMATE SECTION BELOW)
BEYOND TUESDAY...A SLOW WARMING TREND BACK TOWARD NORMAL IS EXPECTED
AS A MORE ZONAL FLOW BEGINS TO DEVELOP. ANOTHER WAVE IS EXPECTED TO
RACE EAST BY THE END OF THE WEEK...THOUGH THE GFS AND ECMWF VARY ON
THE TIMING (GFS FASTER). IN EITHER SCENARIO...A COASTAL LOW AND
POTENTIAL COLD AIR DAMMING SETUP WOULD DEVELOP. CONFIDENCE IN THIS
IS LOW AT THIS TIME..HOWEVER.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1230 PM FRIDAY...
24 HOUR TAF PERIOD: VERY HIGH CONFIDENCE OF VFR CONDITIONS THROUGH
THE END OF THE TAF PERIOD. SKIES WILL BE MOSTLY CLEAR OVERNIGHT AND
THROUGH 18Z SATURDAY AT ALL SITES. GUSTY WINDS THIS AFTERNOON WILL
BEGIN TO DIMINISH FROM WEST TO EAST WITH A NORTHERLY DIRECTION
PREVAILING THROUGH 00Z BUT VARIABLE AFTERWARDS AS WINDS SWING AROUND
TO SOUTHERLY OR SOUTHEASTERLY BY SATURDAY AFTERNOON. NO RESTRICTIONS
WITH CEILINGS OR VISIBILITIES ARE EXPECTED AS VERY DRY AIR WITH HIGH
DEWPOINT DEPRESSIONS MOVE INTO CENTRAL NC.
LONG TERM: THERE WILL BE A CHANCE FOR SOME VERY BRIEF FREEZING RAIN
AT KINT AND KGSO EARLY SUNDAY MORNING FOR AN HOUR OR TWO SOMETIME
BETWEEN 6 AND 12Z. CONFIDENCE IN THIS OCCURRING IS LOW AND EVEN IF
IT DOES...IMPACTS WILL BE LOW AND ACCUMULATIONS WILL BE A HUNDREDTH
OF AN INCH OR LESS...MAINLY ON ELEVATED SURFACES. RAIN CHANCES WILL
INCREASE ON SUNDAY AND CONTINUE THROUGH MONDAY WITH THE NEXT FRONTAL
SYSTEM BEFORE CLEARING OUT ON MONDAY.
&&
.CLIMATE...
RECORD MIN TEMPS FOR JANUARY 7TH
RDU 15 1988
GSO 14 1988
FAY 13 1959
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF
SHORT TERM...ELLIS/DJF/SMITH
LONG TERM...SMITH
AVIATION...ELLIS
CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
256 PM EST THU JAN 02 2014
.SYNOPSIS...A POTENT UPPER LEVEL TROUGH AND ATTENDANT SURFACE LOW
PRESSURE SYSTEM WILL APPROACH THE CAROLINAS FROM THE WEST TODAY. A
STRONG COLD FRONT WILL CROSS CENTRAL NC THIS EVENING. COLD HIGH
PRESSURE WILL BUILD INTO THE REGION IN THE WAKE OF THE FRONT ON
FRIDAY AND FRIDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 940 AM THURSDAY...
LIGHT...ISENTROPICALLY DRIVEN PRECIP INLAND OF AN INVERTED COASTAL
TROUGH IS MOSTLY EAST OF I-95 THIS MORNING. BASED ON RAP 295-305K
LAYER ISENTROPIC ANALYSIS...THIS SHOULD GENERALLY BE THE CASE
THROUGH MIDDAY... PRIOR TO THE ARRIVAL OF A STRONGER SHORTWAVE AND
QG FORCING APPROACHING FROM THE WEST. THE HRRR SHOWS PRECIP
BEGINNING TO FILL IN OVER THE SOUTHERN AND WESTERN CWA AFTER
17Z...ALBEIT MOSTLY LIGHT QPF AMOUNTS OF LESS THAN 0.20" WITH LOWER
PW VALUES TO THE WEST AND LIMITED MOISTURE ABOVE -10C. CATEGORICAL
POPS IN THE CURRENT FORECAST LOOK GOOD...SO THE MAIN CHANGES TO THE
FORECAST WILL JUST BE TO ADJUST TEMPS BASED ON CURRENT TRENDS.
THINNER OVERCAST AND LACK OF PRECIP OVER THE WESTERN PIEDMONT HAS
ALLOWED FOR A LITTLE QUICKER CLIMB THIS MORNING...BUT STRATUS IS
THICKENING FROM THE SOUTHWEST AND ADDITIONAL WARM SHOULD BE VERY
SLOW TO OCCUR. HAVE LOWERED HIGHS A COUPLE DEGREES IN THE NORTHWEST
PIEDMONT...YIELDING 45-50 NORTHWEST TO SOUTHEAST. -SMITH
TONIGHT...A STRONG COLD FRONT ASSOCIATED WITH THE MID-UPPER LEVEL
S/W WILL SWEEP ACROSS CENTRAL NC DURING THE EVENING HOURS. THE
PASSAGE OF THE FRONT WILL BE NOTED BY THE SFC WINDS VEERING TOT HE
NW AND INCREASING TO AROUND 15KTS WITH FREQUENT GUSTS AROUND 25KTS.
THIS NW WIND WILL ADVECT MUCH COLDER AND DRIER AIR INTO CENTRAL NC.
THIS WILL LEAD TO A RAPID DISSIPATION OF THE PRECIPITATION FROM WEST-
TO-EAST IN THE EARLY EVENING WITH CLEARING SKIES OCCURRING SHORTLY
THEREAFTER. MODEL TEMP GUIDANCE HAS BEEN TRENDING COOLER WHICH SEEMS
REASONABLE CONSIDERING UPSTREAM CONDITIONS...SO HAVE FOLLOWED SUIT.
MIN TEMPS BY EARLY FRIDAY IN THE MID 20S NW TO THE LOWER 30S SE.
THESE COLD TEMPS ALONG WITH A BLUSTERY NW WIND WILL SEND WIND CHILL
VALUES DOWN INTO THE TEENS ACROSS THE PIEDMONT BY EARLY FRIDAY
MORNING.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 PM THURSDAY...
SURFACE HIGH PRESSURE WILL BE CENTERED OVER CENTRAL NC WITH MOSTLY
ZONAL FLOW ALOFT. THIS SHOULD KEEP SKIES RELATIVELY CLEAR. A WEAK
WARM AIR ADVECTION REGIME IN THE UPPER LEVELS AND THE DEVELOPMENT OF
RETURN FLOW AROUND THE HIGH AS IT MOVES EASTWARDS WILL HELP MAX
TEMPS CLIMB INTO THE LOW 40S NW TO UPPER 40S SE. AS THE HIGH MOVES
OFFSHORE CLOUD COVER WILL BEGIN TO INCREASE FROM THE SOUTH AND
SURFACE SOUTHERLY FLOW WILL HELP MODERATE LOW TEMPERATURES SATURDAY
NIGHT INTO SUNDAY MORNING INTO THE LOW TO MID 30S AS OPPOSED TO THE
MID-TEENS OF FRIDAY NIGHT/SATURDAY MORNING.
ON SUNDAY MORNING A WEAK IN-SITU CAD SCENARIO WILL DEVELOP WITH THE
SURFACE HIGH MOVING OFF OF THE EASTERN SEABOARD. WITH TEMPERATURES
NEAR THE FREEZING MARK EXPECTED FOR LOWS SUNDAY MORNING AND WET BULB
TEMPERATURES A FEW DEGREES BELOW FREEZING...THERE IS THE POSSIBILITY
FOR SOME FREEZING RAIN BEFORE 8AM IN THE TRIAD. BOTH THE FREEZING
TEMPERATURES AND PRECIPITATION MAY BE LIMITED AND SO THE CHANCES OF
THIS BEING A HIGH IMPACT FREEZING RAIN EVENT ARE LOW. WILL CONTINUE
TO MONITOR TEMPERATURE AND PRECIPITATION TRENDS FOR ANY INCREASED
THREAT BUT FOR NOW WOULD EXPECT MOST FREEZING RAIN TO OCCUR ON
ELEVATED SURFACES AND BRIDGES AND OVERPASSES. TEMPERATURES WILL
REBOUND VERY QUICKLY SUNDAY MORNING AS A DEVELOPING LOW PRESSURE
SYSTEM WEST OF THE MOUNTAINS WILL HELP TO BREAK UP THE CAD BEFORE IT
REALLY EVER GETS STARTED. SOUTHERLY FLOW WILL DEVELOP AHEAD OF THE
FRONTAL SYSTEM AND TEMPERATURES SUNDAY AFTERNOON WILL RAING FROM THE
UPPER 40S NW TO LOWER 60S SE. LOWS SUNDAY NIGHT GENERALLY MIDDLE 30S
TO MIDDLE 40S NW TO SE.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 PM THURSDAY...
THE FRONT WILL MOVE ACROSS THE AREA MONDAY IN THE FORM OF LIQUID
PRECIPITATION BEFORE EXITING TO THE EAST ON MONDAY NIGHT. HIGH TEMPS
MONDAY WILL BE LINKED TO THE PROGRESSION OF THE FRONT. GENERALLY LOW
40S TO MID 50S NW TO SE. QPF ASSICIATED WITH THE FRONT SHOULD BE
AROUND A QUARTER OF AN INCH AT THE MOST.
DRY BUT COLD WILL BE THE THEME FOR THE LONG TERM FROM TUESDAY ON OUT
WITH AN UPPER LEVEL TROUGH PUSHING THROUGH THE AREA ALONG WITH A
1040 MB SURFACE HIGH MOVING THROUGH THE MISSISSIPPI VALLEY. MODERATE
TO STRONG NORTHERLY WINDS AT THE SURFACE WITH STRONG NORTHWESTERLY
WINDS ALOFT WILL BRING A VERY COLD ARCTIC AIRMASS INTO THE REGION.
RECORD LOW TEMPERATURES ARE POSSIBLE AT GSO AND RDU ON MONDAY NIGHT
TUESDAY MORNING WITH LOWS IN THE LOW TO MIDDLE TEENS EXPECTED WITH
WIND CHILLS IN THE SINGLE DIGITS. ONCE THE SURFACE HIGH MOVES
EASTWARD A SLOW WARMING TREND WILL PREVAIL FROM HIGHS IN TEH UPPER
20S TO MID 30S TUESDAY AND LOWS IN THE MID TEENS TO HIGHS IN THE LOW
TO UPPER 40S THURSDAY AND LOWS IN THE LOW TO MID 30S THURSDAY NIGHT.
&&
.AVIATION /18Z THURSDAY THROUGH MONDAY/...
AS OF 105 PM THURSDAY...
A STEADY STREAM OF LIGHT TO MODERATE RAIN ALONG THE NC COAST PLAIN
IS CONTRIBUTING TO IFR AND LIFR CEILINGS FROM KFAY TO NEAR
KRWI...WHILE MVFR CEILINGS ARE SPREADING INTO THE WESTERN PIEDMONT
AHEAD OF A LOW PRESSURE SYSTEM APPROACHING FROM THE WEST.
CONDITIONS ARE EXPECTED TO REMAIN LOW...OR DETERIORATE IN AREAS
WHERE VFR IS CURRENTLY OBSERVED...THERE IS HIGH CONFIDENCE IN A
PERIOD OF AT LEAST IFR CEILINGS BETWEEN 18Z/02 AND 03Z/03...BEFORE A
STRONG COLD FRONT SWEEPS ACROSS THE AREA OVERNIGHT. AS SKIES CLEAR
BEHIND THE FRONT...STRONG NORTHWESTERLY (CROSSWINDS) WINDS MAY GUST
AS HIGH AS 25-30KT...CONTINUING INTO THE DAY ON FRIDAY BEFORE
RELAXING DURING THE AFTERNOON AND EVENING HOURS.
OUTLOOK... SUB-VFR CEILINGS (MOSTLY MVFR) ARE POSSIBLE SATURDAY
NIGHT AS ANOTHER LOW PRESSURE SYSTEM IMPACTS THE AREA. VFR
CONDITIONS ARE THEN EXPECTED NEXT WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...WSS/SMITH
SHORT TERM...ELLIS
LONG TERM...ELLIS
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
105 PM EST THU JAN 02 2014
.SYNOPSIS...A POTENT UPPER LEVEL TROUGH AND ATTENDANT SURFACE LOW
PRESSURE SYSTEM WILL APPROACH THE CAROLINAS FROM THE WEST TODAY. A
STRONG COLD FRONT WILL CROSS CENTRAL NC THIS EVENING. COLD HIGH
PRESSURE WILL BUILD INTO THE REGION IN THE WAKE OF THE FRONT ON
FRIDAY AND FRIDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 940 AM THURSDAY...
LIGHT...ISENTROPICALLY DRIVEN PRECIP INLAND OF AN INVERTED COASTAL
TROUGH IS MOSTLY EAST OF I-95 THIS MORNING. BASED ON RAP 295-305K
LAYER ISENTROPIC ANALYSIS...THIS SHOULD GENERALLY BE THE CASE
THROUGH MIDDAY... PRIOR TO THE ARRIVAL OF A STRONGER SHORTWAVE AND
QG FORCING APPROACHING FROM THE WEST. THE HRRR SHOWS PRECIP
BEGINNING TO FILL IN OVER THE SOUTHERN AND WESTERN CWA AFTER
17Z...ALBEIT MOSTLY LIGHT QPF AMOUNTS OF LESS THAN 0.20" WITH LOWER
PW VALUES TO THE WEST AND LIMITED MOISTURE ABOVE -10C. CATEGORICAL
POPS IN THE CURRENT FORECAST LOOK GOOD...SO THE MAIN CHANGES TO THE
FORECAST WILL JUST BE TO ADJUST TEMPS BASED ON CURRENT TRENDS.
THINNER OVERCAST AND LACK OF PRECIP OVER THE WESTERN PIEDMONT HAS
ALLOWED FOR A LITTLE QUICKER CLIMB THIS MORNING...BUT STRATUS IS
THICKENING FROM THE SOUTHWEST AND ADDITIONAL WARM SHOULD BE VERY
SLOW TO OCCUR. HAVE LOWERED HIGHS A COUPLE DEGREES IN THE NORTHWEST
PIEDMONT...YIELDING 45-50 NORTHWEST TO SOUTHEAST. -SMITH
TONIGHT...A STRONG COLD FRONT ASSOCIATED WITH THE MID-UPPER LEVEL
S/W WILL SWEEP ACROSS CENTRAL NC DURING THE EVENING HOURS. THE
PASSAGE OF THE FRONT WILL BE NOTED BY THE SFC WINDS VEERING TOT HE
NW AND INCREASING TO AROUND 15KTS WITH FREQUENT GUSTS AROUND 25KTS.
THIS NW WIND WILL ADVECT MUCH COLDER AND DRIER AIR INTO CENTRAL NC.
THIS WILL LEAD TO A RAPID DISSIPATION OF THE PRECIPITATION FROM WEST-
TO-EAST IN THE EARLY EVENING WITH CLEARING SKIES OCCURRING SHORTLY
THEREAFTER. MODEL TEMP GUIDANCE HAS BEEN TRENDING COOLER WHICH SEEMS
REASONABLE CONSIDERING UPSTREAM CONDITIONS...SO HAVE FOLLOWED SUIT.
MIN TEMPS BY EARLY FRIDAY IN THE MID 20S NW TO THE LOWER 30S SE.
THESE COLD TEMPS ALONG WITH A BLUSTERY NW WIND WILL SEND WIND CHILL
VALUES DOWN INTO THE TEENS ACROSS THE PIEDMONT BY EARLY FRIDAY
MORNING.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
AS OF 315 AM THURSDAY...
FRIDAY AND FRIDAY NIGHT...ARCTIC-LIKE AIR MASS WILL SETTLE OVER
CENTRAL NC AS THE PARENT HIGH PRESSURE SYSTEM BUILDS INTO AND
SETTLES OVERHEAD BY FRIDAY NIGHT. SUSTAINED WINDS NEAR 20 MPH WITH
GUSTS 30-35 MPH WILL BE COMMON FRIDAY MORNING AFTERWHICH THE WINDS
WILL GRADUALLY SUBSIDE IN THE AFTERNOON. COULD SEE A FEW GUSTS
BETWEEN 40-45 MPH BUT BELIEVE THIS OCCURRENCE WILL BE LIMITED/FAIRLY
RANDOM. THUS...WILL NOT ISSUE A WIND ADVISORY WITH THIS PACKAGE BUT
LATER FORECAST ISSUANCES MAY NEED TO CONSIDER ONE. MAX TEMPS FRIDAY
WILL BE CLOSE TO 20 DEGREES BELOW NORMAL AS MAX TEMPS SHOULD RANGE
FROM THE LOW-MID 30S NORTH TO UPPER 30S TO NEAR 40 SOUTH.
UNDER CLEAR SKIES AND A SUBSIDING WIND REGIME...TEMPS WILL PLUMMET
AFTER SUNSET. AGAIN...MOS GUIDANCE HAS COME IN A LITTLE COLDER AND
PLAN TO ADJUST MIN TEMPS IN A SIMILAR FASHION. MIN TEMPS SHOULD
RANGE FROM THE MIDDLE TEENS IN THE OUTLYING AREAS...TO THE UPPER
TEENS AROUND 20 IN THE MORE URBANIZED LOCATIONS. -WSS
SATURDAY: ARCTIC HIGH PRESSURE OVER THE AREA TO START THE DAY ON
SATURDAY COUPLED WITH ONLY SHALLOW AFTERNOON MIXING WILL LEAD TO
WELL BELOW NORMAL TEMPS FOR SATURDAY... DESPITE THE HIGH MOVING
OFFSHORE ALLOWING FOR RETURN FLOW TO DEVELOP. GIVEN THIS AND BRIEF
MID LEVEL RIDGING ACROSS THE AREA EXPECT WE WILL SEE MOSTLY SUNNY
SKIES WITH HIGH TEMPS IN THE LOWER TO MID 40S. -BSD
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...
SATURDAY NIGHT THROUGH MONDAY: A MID/UPPER LEVEL TROUGH WILL DEEPEN
SATURDAY INTO SUNDAY ACROSS THE CENTRAL U.S. AND BEGIN TO MOVE
EASTWARD ALLOWING ARCTIC AIR TO FLOOD INTO THE CENTRAL AND
EVENTUALLY EASTERN U.S. BEHIND AN ASSOCIATED ARCTIC COLD FRONT.
AHEAD OF THE FRONT ACROSS OUR AREA ON SATURDAY NIGHT INTO SUNDAY
EXPECT WE WILL SEE ISENTROPIC LIFT INCREASE AS 850 MB WINDS ACROSS
OUR WESTERN PIEDMONT INCREASE INTO THE 30 TO 40 KT RANGE SATURDAY
NIGHT INTO SUNDAY. WITH THE INCREASE MOISTURE AND SHALLOW ISENTROPIC
LIFT NWP GUIDANCE IS SHOWING SOME PRECIP DEVELOPING ACROSS OUR
WESTERN /NORTHWESTERN PIEDMONT VERY LATE SATURDAY INTO SUNDAY
MORNING. BOTH THE NAM AND GFS BUFR SOUNDING SHOW THE MOISTURE WILL
BE QUITE SHALLOW... WITH SATURATION NOT EVEN REACHING -10 DEGREES
CELSIUS. HOWEVER... FORECAST WETBULB TEMPS ARE EXPECTED TO BE BELOW
FREEZING ACROSS THE WESTERN AND NORTHWESTERN PIEDMONT WHEN PRECIP
MAY BEGIN TO MOVE INTO THE AREA EARLY SUNDAY MORNING... GIVEN THE
DRY AIR DEPOSITED BY THE ARCTIC SURFACE HIGH. THUS... EXPECT WE
COULD SEE A IN-SITU CAD AIRMASS DEVELOP... WITH POSSIBLY A FEW HOURS
OF FREEZING RAIN IN THE IN THE FAVORED NORTHWEST/WESTERN PIEDMONT.
THUS... HAVE ADDED RAIN AND/OR FREEZING RAIN WORDING TO THE FORECAST
WHEN TEMPS ARE EXPECTED TO BE 32 F OR LESS AND PRECIP IS IN THE
FORECAST FOR SUNDAY MORNING. GIVEN THE LATENT HEAT RELEASE FROM
PHASE CHANGE AND NO CONTINUED SOURCE OF DRY COLD AIR EXPECTED...
FREEZING RAIN SHOULD NOT LAST LONG AND ONLY BE A "NUISANCE" TYPE
EVENT... WITH ALL RAIN EXPECTED BY 15Z SUNDAY (GIVEN CURRENT TIMING
OF THE PRECIP AND ONLY A COUPLE TENTHS OF AN INCH AT BEST OF LIQUID
). WILL SHOW THE HIGHEST POPS IN THE NORTHWEST/WEST WHERE MOISTURE
AND LIFT APPEAR TO BE MAXIMIZED.
THIS FIRST AREA OF PRECIP WILL BEGIN TO LIFT OFF TO THE NORTHEAST OF
THE AREA ON SUNDAY AFTERNOON AS THE ARCTIC SURFACE FRONT APPROACHES
THE CENTRAL AND SOUTHERN APPALACHIAN MOUNTAINS. THIS CREATES A
DIFFICULT TEMP FORECAST... WITH THE POSSIBLE LINGERING CAD AIRMASS.
FOR NOW WILL LOWER HIGHS IN THE NORTHWEST AND RAISE HIGHS A BIT IN
THE SOUTHEAST. THIS YIELDS HIGH TEMP RANGING FROM THE MID 40S NW
(WHICH MAY BE TOO WARM) TO LOWER TO MID 60S SE.
THE ARCTIC FRONT IS EXPECTED TO MOVE THROUGH THE AREA EARLY MONDAY
MORNING... WITH THE BULK OF THE COLD AIR POSSIBLY DELAYED A BIT...
AS THE GFS AND ECMWF DIFFER IN HOW FAST THE LOW LEVEL THICKNESS
VALUES WILL PLUNGE AND THE COLD AIR ROARS IN HERE. FOR NOW WILL SHOW
TEMPS RANGING FROM THE LOWER 40S NW TO THE MID 50S E... WITH LOWS
MONDAY MORNING IN THE MID 30S TO THE LOWER 40S... WITH POSSIBLY A
FEW SHOWERS ACCOMPANYING THE FRONT AND MAYBE EVEN A FEW SNOW SHOWERS
ACROSS THE FAR NORTH/NORTHWEST (STILL TOO EARLY TO TELL IF THE COLD
AIR WILL BE ABLE TO CAUGHT UP WITH THE PRECIP).
MONDAY NIGHT THROUGH WEDNESDAY: ARCTIC HIGH PRESSURE WILL BUILD
ACROSS THE AREA DURING THIS TIME FRAME WITH SOME THE COLDEST AIR OF
THE SEASON... WITH HIGHS ON TUESDAY STRUGGLING TO REACH 30 DEGREES
FOR SOME LOCATIONS. THUS... EXPECT DRY BUT COLD CONDITIONS DURING
THIS TIME FRAME WITH WELL BELOW NORMAL TEMPS.
&&
.AVIATION /18Z THURSDAY THROUGH MONDAY/...
AS OF 105 PM THURSDAY...
A STEADY STREAM OF LIGHT TO MODERATE RAIN ALONG THE NC COAST PLAIN
IS CONTRIBUTING TO IFR AND LIFR CEILINGS FROM KFAY TO NEAR
KRWI...WHILE MVFR CEILINGS ARE SPREADING INTO THE WESTERN PIEDMONT
AHEAD OF A LOW PRESSURE SYSTEM APPROACHING FROM THE WEST.
CONDITIONS ARE EXPECTED TO REMAIN LOW...OR DETERIORATE IN AREAS
WHERE VFR IS CURRENTLY OBSERVED...THERE IS HIGH CONFIDENCE IN A
PERIOD OF AT LEAST IFR CEILINGS BETWEEN 18Z/02 AND 03Z/03...BEFORE A
STRONG COLD FRONT SWEEPS ACROSS THE AREA OVERNIGHT. AS SKIES CLEAR
BEHIND THE FRONT...STRONG NORTHWESTERLY (CROSSWINDS) WINDS MAY GUST
AS HIGH AS 25-30KT...CONTINUING INTO THE DAY ON FRIDAY BEFORE
RELAXING DURING THE AFTERNOON AND EVENING HOURS.
OUTLOOK... SUB-VFR CEILINGS (MOSTLY MVFR) ARE POSSIBLE SATURDAY
NIGHT AS ANOTHER LOW PRESSURE SYSTEM IMPACTS THE AREA. VFR
CONDITIONS ARE THEN EXPECTED NEXT WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...WSS/SMITH
SHORT TERM...WSS/BSD
LONG TERM...BSD
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
940 AM EST THU JAN 02 2014
.SYNOPSIS...A POTENT UPPER LEVEL TROUGH AND ATTENDANT SURFACE LOW
PRESSURE SYSTEM WILL APPROACH THE CAROLINAS FROM THE WEST TODAY. A
STRONG COLD FRONT WILL CROSS CENTRAL NC THIS EVENING. COLD HIGH
PRESSURE WILL BUILD INTO THE REGION IN THE WAKE OF THE FRONT ON
FRIDAY AND FRIDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 940 AM THURSDAY...
LIGHT...ISENTROPICALLY DRIVEN PRECIP INLAND OF AN INVERTED COASTAL
TROUGH IS MOSTLY EAST OF I-95 THIS MORNING. BASED ON RAP 295-305K
LAYER ISENTROPIC ANALYSIS...THIS SHOULD GENERALLY BE THE CASE
THROUGH MIDDAY... PRIOR TO THE ARRIVAL OF A STRONGER SHORTWAVE AND
QG FORCING APPROACHING FROM THE WEST. THE HRRR SHOWS PRECIP
BEGINNING TO FILL IN OVER THE SOUTHERN AND WESTERN CWA AFTER
17Z...ALBEIT MOSTLY LIGHT QPF AMOUNTS OF LESS THAN 0.20" WITH LOWER
PW VALUES TO THE WEST AND LIMITED MOISTURE ABOVE -10C. CATEGORICAL
POPS IN THE CURRENT FORECAST LOOK GOOD...SO THE MAIN CHANGES TO THE
FORECAST WILL JUST BE TO ADJUST TEMPS BASED ON CURRENT TRENDS.
THINNER OVERCAST AND LACK OF PRECIP OVER THE WESTERN PIEDMONT HAS
ALLOWED FOR A LITTLE QUICKER CLIMB THIS MORNING...BUT STRATUS IS
THICKENING FROM THE SOUTHWEST AND ADDITIONAL WARM SHOULD BE VERY
SLOW TO OCCUR. HAVE LOWERED HIGHS A COUPLE DEGREES IN THE NORTHWEST
PIEDMONT...YIELDING 45-50 NORTHWEST TO SOUTHEAST. -SMITH
TONIGHT...A STRONG COLD FRONT ASSOCIATED WITH THE MID-UPPER LEVEL
S/W WILL SWEEP ACROSS CENTRAL NC DURING THE EVENING HOURS. THE
PASSAGE OF THE FRONT WILL BE NOTED BY THE SFC WINDS VEERING TOT HE
NW AND INCREASING TO AROUND 15KTS WITH FREQUENT GUSTS AROUND 25KTS.
THIS NW WIND WILL ADVECT MUCH COLDER AND DRIER AIR INTO CENTRAL NC.
THIS WILL LEAD TO A RAPID DISSIPATION OF THE PRECIPITATION FROM WEST-
TO-EAST IN THE EARLY EVENING WITH CLEARING SKIES OCCURRING SHORTLY
THEREAFTER. MODEL TEMP GUIDANCE HAS BEEN TRENDING COOLER WHICH SEEMS
REASONABLE CONSIDERING UPSTREAM CONDITIONS...SO HAVE FOLLOWED SUIT.
MIN TEMPS BY EARLY FRIDAY IN THE MID 20S NW TO THE LOWER 30S SE.
THESE COLD TEMPS ALONG WITH A BLUSTERY NW WIND WILL SEND WIND CHILL
VALUES DOWN INTO THE TEENS ACROSS THE PIEDMONT BY EARLY FRIDAY
MORNING.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
AS OF 315 AM THURSDAY...
FRIDAY AND FRIDAY NIGHT...ARCTIC-LIKE AIR MASS WILL SETTLE OVER
CENTRAL NC AS THE PARENT HIGH PRESSURE SYSTEM BUILDS INTO AND
SETTLES OVERHEAD BY FRIDAY NIGHT. SUSTAINED WINDS NEAR 20 MPH WITH
GUSTS 30-35 MPH WILL BE COMMON FRIDAY MORNING AFTERWHICH THE WINDS
WILL GRADUALLY SUBSIDE IN THE AFTERNOON. COULD SEE A FEW GUSTS
BETWEEN 40-45 MPH BUT BELIEVE THIS OCCURRENCE WILL BE LIMITED/FAIRLY
RANDOM. THUS...WILL NOT ISSUE A WIND ADVISORY WITH THIS PACKAGE BUT
LATER FORECAST ISSUANCES MAY NEED TO CONSIDER ONE. MAX TEMPS FRIDAY
WILL BE CLOSE TO 20 DEGREES BELOW NORMAL AS MAX TEMPS SHOULD RANGE
FROM THE LOW-MID 30S NORTH TO UPPER 30S TO NEAR 40 SOUTH.
UNDER CLEAR SKIES AND A SUBSIDING WIND REGIME...TEMPS WILL PLUMMET
AFTER SUNSET. AGAIN...MOS GUIDANCE HAS COME IN A LITTLE COLDER AND
PLAN TO ADJUST MIN TEMPS IN A SIMILAR FASHION. MIN TEMPS SHOULD
RANGE FROM THE MIDDLE TEENS IN THE OUTLYING AREAS...TO THE UPPER
TEENS AROUND 20 IN THE MORE URBANIZED LOCATIONS. -WSS
SATURDAY: ARCTIC HIGH PRESSURE OVER THE AREA TO START THE DAY ON
SATURDAY COUPLED WITH ONLY SHALLOW AFTERNOON MIXING WILL LEAD TO
WELL BELOW NORMAL TEMPS FOR SATURDAY... DESPITE THE HIGH MOVING
OFFSHORE ALLOWING FOR RETURN FLOW TO DEVELOP. GIVEN THIS AND BRIEF
MID LEVEL RIDGING ACROSS THE AREA EXPECT WE WILL SEE MOSTLY SUNNY
SKIES WITH HIGH TEMPS IN THE LOWER TO MID 40S. -BSD
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...
SATURDAY NIGHT THROUGH MONDAY: A MID/UPPER LEVEL TROUGH WILL DEEPEN
SATURDAY INTO SUNDAY ACROSS THE CENTRAL U.S. AND BEGIN TO MOVE
EASTWARD ALLOWING ARCTIC AIR TO FLOOD INTO THE CENTRAL AND
EVENTUALLY EASTERN U.S. BEHIND AN ASSOCIATED ARCTIC COLD FRONT.
AHEAD OF THE FRONT ACROSS OUR AREA ON SATURDAY NIGHT INTO SUNDAY
EXPECT WE WILL SEE ISENTROPIC LIFT INCREASE AS 850 MB WINDS ACROSS
OUR WESTERN PIEDMONT INCREASE INTO THE 30 TO 40 KT RANGE SATURDAY
NIGHT INTO SUNDAY. WITH THE INCREASE MOISTURE AND SHALLOW ISENTROPIC
LIFT NWP GUIDANCE IS SHOWING SOME PRECIP DEVELOPING ACROSS OUR
WESTERN /NORTHWESTERN PIEDMONT VERY LATE SATURDAY INTO SUNDAY
MORNING. BOTH THE NAM AND GFS BUFR SOUNDING SHOW THE MOISTURE WILL
BE QUITE SHALLOW... WITH SATURATION NOT EVEN REACHING -10 DEGREES
CELSIUS. HOWEVER... FORECAST WETBULB TEMPS ARE EXPECTED TO BE BELOW
FREEZING ACROSS THE WESTERN AND NORTHWESTERN PIEDMONT WHEN PRECIP
MAY BEGIN TO MOVE INTO THE AREA EARLY SUNDAY MORNING... GIVEN THE
DRY AIR DEPOSITED BY THE ARCTIC SURFACE HIGH. THUS... EXPECT WE
COULD SEE A IN-SITU CAD AIRMASS DEVELOP... WITH POSSIBLY A FEW HOURS
OF FREEZING RAIN IN THE IN THE FAVORED NORTHWEST/WESTERN PIEDMONT.
THUS... HAVE ADDED RAIN AND/OR FREEZING RAIN WORDING TO THE FORECAST
WHEN TEMPS ARE EXPECTED TO BE 32 F OR LESS AND PRECIP IS IN THE
FORECAST FOR SUNDAY MORNING. GIVEN THE LATENT HEAT RELEASE FROM
PHASE CHANGE AND NO CONTINUED SOURCE OF DRY COLD AIR EXPECTED...
FREEZING RAIN SHOULD NOT LAST LONG AND ONLY BE A "NUISANCE" TYPE
EVENT... WITH ALL RAIN EXPECTED BY 15Z SUNDAY (GIVEN CURRENT TIMING
OF THE PRECIP AND ONLY A COUPLE TENTHS OF AN INCH AT BEST OF LIQUID
). WILL SHOW THE HIGHEST POPS IN THE NORTHWEST/WEST WHERE MOISTURE
AND LIFT APPEAR TO BE MAXIMIZED.
THIS FIRST AREA OF PRECIP WILL BEGIN TO LIFT OFF TO THE NORTHEAST OF
THE AREA ON SUNDAY AFTERNOON AS THE ARCTIC SURFACE FRONT APPROACHES
THE CENTRAL AND SOUTHERN APPALACHIAN MOUNTAINS. THIS CREATES A
DIFFICULT TEMP FORECAST... WITH THE POSSIBLE LINGERING CAD AIRMASS.
FOR NOW WILL LOWER HIGHS IN THE NORTHWEST AND RAISE HIGHS A BIT IN
THE SOUTHEAST. THIS YIELDS HIGH TEMP RANGING FROM THE MID 40S NW
(WHICH MAY BE TOO WARM) TO LOWER TO MID 60S SE.
THE ARCTIC FRONT IS EXPECTED TO MOVE THROUGH THE AREA EARLY MONDAY
MORNING... WITH THE BULK OF THE COLD AIR POSSIBLY DELAYED A BIT...
AS THE GFS AND ECMWF DIFFER IN HOW FAST THE LOW LEVEL THICKNESS
VALUES WILL PLUNGE AND THE COLD AIR ROARS IN HERE. FOR NOW WILL SHOW
TEMPS RANGING FROM THE LOWER 40S NW TO THE MID 50S E... WITH LOWS
MONDAY MORNING IN THE MID 30S TO THE LOWER 40S... WITH POSSIBLY A
FEW SHOWERS ACCOMPANYING THE FRONT AND MAYBE EVEN A FEW SNOW SHOWERS
ACROSS THE FAR NORTH/NORTHWEST (STILL TOO EARLY TO TELL IF THE COLD
AIR WILL BE ABLE TO CAUGHT UP WITH THE PRECIP).
MONDAY NIGHT THROUGH WEDNESDAY: ARCTIC HIGH PRESSURE WILL BUILD
ACROSS THE AREA DURING THIS TIME FRAME WITH SOME THE COLDEST AIR OF
THE SEASON... WITH HIGHS ON TUESDAY STRUGGLING TO REACH 30 DEGREES
FOR SOME LOCATIONS. THUS... EXPECT DRY BUT COLD CONDITIONS DURING
THIS TIME FRAME WITH WELL BELOW NORMAL TEMPS.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 640 AM THURSDAY...
A STRONG MID-UPPER LEVEL TROUGH APPROACHING FROM THE WEST
INTERACTING WITH AVAILABLE MOISTURE OVER THE CAROLINAS WILL CAUSE
AREAS OF RAIN TO GRADUALLY EXPAND NORTHWARD ACROSS CENTRAL NC THIS
MORNING. THE RAIN FALLING THROUGH THE RELATIVELY DRY SUB-CLOUD LAYER
WILL MOISTEN THE NEAR SURFACE AIR MASS LEADING TO THE DEVELOPMENT OF
WIDESPREAD IFR/LOW END MVFR CEILINGS LATER THIS MORNING (MAINLY
AFTER 15Z). THE AREAS OF RAIN LATE THIS MORNING INTO THE AFTERNOON
WILL LIMIT THE VISIBILITY BETWEEN 3-5SM WITH POCKETS OF 2SM
POSSIBLE.
BETWEEN 00Z-04Z FRIDAY...A STRONG COLD FRONT WILL SWEEP ACROSS THE
REGION. SFC WINDS WILL VEER TO THE NW AND INCREASE TO AROUND 15KTS
WITH FREQUENT GUSTS 25-30KTS. THIS WIND WILL ADVECT MUCH DRIER AND
COLDER AIR INTO CENTRAL NC...CAUSING THE LIGHT RAIN AND CLOUD COVER
TO QUICKLY DISSIPATE. EXPECT VFR CONDITIONS IN THE TRIAD REGION
SHORTLY AFTER 00Z...AND IN THE KRWI AND KFAY VICINITIES BY 03Z-04Z.
THE WINDY CONDITIONS WILL PERSIST OVERNIGHT INTO FRIDAY WITH
FREQUENT GUSTS AROUND 30KTS THROUGH 18Z FRIDAY. WINDS WILL BEGIN TO
SUBSIDE FRIDAY AFTERNOON AS A HIGH PRESSURE SYSTEM SETTLES OVERHEAD.
THIS WEATHER SYSTEM WILL MAINTAIN VFR CONDITIONS FRIDAY THROUGH
SATURDAY AFTERNOON.
THE NEXT THREAT FOR SUB-VFR CONDITIONS WILL OCCUR SATURDAY NIGHT
INTO SUNDAY AS ANOTHER MID-UPPER LEVEL TROUGH APPROACHES FROM THE
WEST. THIS WEATHER SYSTEM MAY CAUSE AREAS OF LIGHT PRECIPITATION TO
BREAK OUT LATE SATURDAY NIGHT INTO SUNDAY...LEADING TO MVFR
CEILINGS. A RETURN TO VFR CONDITIONS ANTICIPATED FOR MONDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...WSS/SMITH
SHORT TERM...WSS/BSD
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1141 PM CST WED JAN 1 2014
.UPDATE...FOR 06Z AVIATION FORECAST
&&
.AVIATION...
SFC LOW PRESSURE FROM SW ARKANSAS TO NEAR PAH WILL CONTINUE TO
QUICKLY MOVE EASTWARD. MOISTURE POOLING AHEAD OF THIS LOW/S COLD
FRONT WILL HELP DETERIORATE CONDITIONS AT THE TERMINALS. HAVE
VCSH/TEMPOS FOR LIGHT RAIN NEARING 12Z THOUGH THERE COULD BE
BREAKS IN THE PRECIP. THEREAFTER...WITH THE COLD FRONTAL PASSAGE
ANY RAIN MAY CHANGEOVER TO A RASN MIX OR JUST SN AT THE TAF SITES
AS WINDS SHIFT AROUND TO THE NW AND BECOME QUITE GUSTY FROM LATE
THURS MORNING THROUGH THE REST OF THE TAF PERIOD. IFR TO LOW MVFR
CONDITIONS ARE EXPECTED WITH THE FROPA UNTIL ROUGHLY 00Z FRI.
&&
.PREV DISCUSSION... /ISSUED 849 PM CST WED JAN 1 2014/
UPDATE...
LATEST MOSAIC AND OHX RADAR IMAGERY SHOW LIGHT RAIN HAS ALREADY
DEVELOPED ACROSS WESTERN TN WITH ECHOES NOW SPREADING INTO
WESTERN ZONES. BASED ON THIS ADJUSTED POPS UPWARD FOR THE
REMAINDER OF THE NIGHT FOR ALL ZONES...WITH PRECIP CHANCES NOW
MORE IN LINE WITH 18Z/00Z RUNS. TEMPS SEEM REASONABLE AND WERE NOT
CHANGED...WITH TEMPS LIKELY FALLING SOME MORE THIS EVENING BEFORE
BECOMING STEADY OR RISING OVERNIGHT AS WAA INCREASES.
FOR THURSDAY...THE JUST IN 00Z NAM CONTINUES TO SHOW STRONG COLD
FRONT RACING ACROSS THE AREA DURING THE MORNING HOURS WITH
PRECIPITATION EXITING RIGHT ON ITS HEELS. AS WITH THE
GFS/ECMWF...NAM SHOWS MOISTURE MOVING OUT AT SAME TIME AS COLD AIR
RUSHES IN WITH ONLY A BRIEF WINDOW FOR A MIX/CHANGEOVER TO SNOW
DURING THE MORNING AND EARLY AFTERNOON HOURS FOR LOCATIONS WEST OF
THE PLATEAU. 01Z RAP AGREES WITH THIS SCENARIO...WHILE 18Z
GFS/12Z ECMWF ARE COLDER WITH PRECIPITATION LINGERING LONGER
BEHIND THE FRONT. THUS APPEARS BEST CHANCE FOR ANY SNOW ACCUMS
WEST OF THE PLATEAU ON THURSDAY WILL BE ACROSS NORTHWEST ZONES
WHERE WAA WILL HAVE LESS IMPACT AND CAA ARRIVES QUICKEST...AND A
DUSTING TO HALF INCH OF SNOW SEEMS POSSIBLE THERE. REST OF THE
CWA OFF THE PLATEAU MAY STAY TOO WARM BEFORE PRECIP EXITS WITH
LITTLE IF ANY SNOW ACCUMS. ON THE PLATEAU...WEST TO NORTHWEST
FLOW WILL FORCE MOISTURE UP THE HIGHER TERRAIN AND CHANGE RAIN
OVER TO SNOW DURING THE AFTERNOON...WITH LIGHT SNOW CONTINUING
INTO AT LEAST THE EVENING HOURS. APPEARS AREAS FROM MONTEREY TO
CROSSVILLE TO JAMESTOWN COULD EASILY SEE AROUND 1 INCH OF SNOW
ACCUM...POSSIBLY HIGHER...AND A WINTER WEATHER ADVISORY MAY BE
NEEDED FOR THE NORTHERN PLATEAU COUNTIES MAINLY DUE TO TRAVEL
IMPACTS AS TEMPERATURES FALL INTO THE 20S AND 10S BEFORE SNOW
COMES TO AN END. WILL LET MID SHIFT TAKE A LOOK AT THE FULL 00Z
MODEL SUITE BEFORE DECIDING ON WHETHER A WWA IS NEEDED.
SHAMBURGER
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AL
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
907 PM CST FRI JAN 3 2014
.UPDATE...
A LOW LEVEL JET OF 35 TO 45 KNOTS WILL HELPS KEEP SURFACE WINDS UP
OVERNIGHT AND AID IN THE NORTHERLY TRANSPORT OF LOW CLOUDS ACROSS
THE REGION. EXPECT THE LOW CLOUDS TO BEGIN FORMING SOUTH OF OUR
CWA BY 2 AM. HAVE UPDATED GRIDS TO REFLECT THESE TRENDS AND AS
WELL AS A SLIGHT SLOW DOWN IN DEWPOINT INCREASES BY MORNING. 75
THE ZONE FORECAST WILL NOT BE AMENDED THIS EVENING...BUT THE
OTHER PRODUCTS WILL BE. 75
&&
.AVIATION...
/00Z TAFS/
WIND SPEEDS AND CIGS WILL BE THE MAIN THE CHALLENGE FIRST 12 HOURS
OF THE TAF CYCLE...THEN FROPA TIMING IN THE 24-30 HR PERIOD AT DFW
SATURDAY EVENING.
A SHORTWAVE WILL MOVE ACROSS AND PRODUCE SCATTERED CIRRUS OVERNIGHT
WITH SSE WINDS 10-15 KTS. BUFR AND RUC FORECAST SOUNDINGS ALL
INDICATE STRATUS RAPIDLY DEVELOPING AFTER MIDNIGHT AND MOVING UP
QUICKLY ON A 50 KT+ SSWLY LLJ. NAM/SREF/AND RUC ALL INDICATE
POTENTIAL FOR IFR BY 12Z...ESPECIALLY AT WACO. CONFIDENCE IS NOT
AS HIGH AT DFW METRO AIRPORTS AND WILL MAINTAIN LOW MVFR FOR NOW
WITH A TEMPO GROUP FOR IFR AROUND 12Z FOR WACO. BETTER CONFIDENCE
WILL LIKELY OCCUR WITH THE 06Z TAF ISSUANCE REGARDING IFR CIGS.
OTHERWISE...SOUTH WINDS 15-20 KTS DURING THE MORNING SATURDAY
WILL BECOME GUSTY BY MIDDAY...BEFORE VEERING WSWLY AHEAD OF A
FROPA IN THE DFW AREA BY 00Z SUNDAY. HAVE INTRODUCED A 24-30 HR
FORECAST PERIOD FOR THE ARRIVAL OF AN ARCTIC FRONT WITH WINDS
SHIFTING NORTHWEST NEAR 15 KTS. FROPA AT WACO WILL LIKELY OCCUR
AROUND 06Z SUNDAY OR AFTER. 05/
&&
.PREV DISCUSSION... /ISSUED 351 PM CST FRI JAN 3 2014/
A WARM AIR ADVECTION PATTERN WILL CONTINUE ACROSS THE REGION TONIGHT
THROUGH SATURDAY AS SURFACE LOW PRESSURE DEEPENS FROM THE NORTHERN
PLAINS TO THE SOUTHERN HIGH PLAINS. OVERNIGHT LOWS TONIGHT WILL BE
ABOVE FREEZING IN MOST LOCATIONS AND AFTERNOON HIGHS SATURDAY WILL
RANGE FROM THE MIDDLE 50S TO THE MIDDLE 60S. HOWEVER...THE WARM
WEATHER WILL BE SHORT-LIVED AS AN ARCTIC HIGH BUILDS SOUTHWARD
ACROSS THE PLAINS AND PUSHES A STRONG COLD FRONT ACROSS THE STATE.
THE FRONT SHOULD MOVE INTO THE NORTHWEST ZONES SATURDAY AFTERNOON
AND THROUGH THE ENTIRE FORECAST AREA SATURDAY NIGHT. THE FRONT
WILL BRING SHARPLY FALLING TEMPERATURES AND GUSTY NORTH WINDS.
THERE WILL BE A SLIGHT CHANCE OF RAIN NEAR THE FRONT SATURDAY
NIGHT...MAINLY ACROSS THE EASTERN COUNTIES...WHERE MOISTURE WILL
BE MOST ABUNDANT. TEMPERATURES SHOULD REMAIN ABOVE FREEZING WHERE
THE RAIN WILL FALL SATURDAY NIGHT SO NO FREEZING PRECIPITATION IS
EXPECTED.
EXTREMELY DRY AND COLDER AIR WILL PREVAIL ACROSS NORTH TEXAS ON
SUNDAY. HIGH TEMPERATURES WILL ONLY REACH THE UPPER 30S TO MIDDLE
40S. VERY COLD CONDITIONS WILL BEGIN SUNDAY NIGHT AND CONTINUE
THROUGH MONDAY AS SKIES CLEAR AND WINDS DECREASE. LOWS MONDAY
MORNING WILL RANGE FROM THE TEENS TO THE LOWER 20S WITH HIGHS
MONDAY FROM THE UPPER 20S IN THE NORTHWEST TO THE LOWER 40S IN THE
SOUTH.
IT WILL BE COLD AGAIN MONDAY NIGHT/TUESDAY MORNING WITH A
RELATIVELY LIGHT WIND...A CLEAR SKY AND DRY AIR IN PLACE. LOWS
TUESDAY MORNING WILL ONCE AGAIN BE IN THE TEENS AND 20S.
A RECOVERY FROM THE DRY AND COLD ARCTIC AIR WILL BEGIN ON TUESDAY
AS A SURFACE LEE TROUGH DEVELOPS AND THE GULF BEGINS TO OPEN UP.
THE GFS IS INDICATING THAT A FEW SHOWERS MAY DEVELOP OVERNIGHT TUESDAY
IN THE EAST...BUT THE ECMWF SOLUTION DOES NOT RECOVER THE
MOISTURE AS QUICKLY AND KEEPS PRECIP OUT OF NORTH TEXAS UNTIL WEDNESDAY.
THE ECMWF APPEARS TO BE A MORE REALISTIC SOLUTION WITH REGARDS TO THE
MOISTURE RETURN AFTER THE SCOURING BEHIND THE ARCTIC FRONT.
THEREFORE...WE WILL REMOVE ALL POPS FOR TUESDAY NIGHT. RAIN
CHANCES WILL INCREASE ON WEDNESDAY AS AN UPPER TROUGH APPROACHES
FROM THE WEST. THE BEST RAIN CHANCES WILL BE ACROSS THE EAST WHERE
MOISTURE WILL BE MOST ABUNDANT. MID LEVEL INSTABILITY LOOKS
INSUFFICIENT FOR THUNDER AT THIS TIME. RAIN CHANCES WILL CONTINUE
THROUGH THURSDAY AS A COLD FRONT MOVES INTO THE REGION. THE MODELS
HAVE BACKED OFF ON THE MOVEMENT OF THE UPPER TROUGH.
THEREFORE...THE COLD FRONT IS PROGGED TO STALL ACROSS THE REGION
THURSDAY AND LIFT BACK TO THE NORTH ON FRIDAY. WE HAVE DECIDED TO
KEEP SOME LOW POPS IN THE FORECAST THURSDAY THROUGH FRIDAY FOR
NOW AND AWAIT SOME MODEL CONSISTENCY AND AGREEMENT.
79
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 35 64 28 40 21 / 0 10 5 5 0
WACO, TX 40 64 32 42 21 / 0 10 10 5 0
PARIS, TX 30 56 34 34 14 / 5 10 20 5 5
DENTON, TX 37 61 26 37 16 / 0 10 5 5 0
MCKINNEY, TX 35 59 28 35 15 / 0 10 10 5 5
DALLAS, TX 39 61 31 40 19 / 0 10 10 5 5
TERRELL, TX 37 58 31 39 17 / 5 10 10 5 5
CORSICANA, TX 38 60 33 41 19 / 5 10 10 5 0
TEMPLE, TX 37 65 34 43 20 / 0 10 10 10 0
MINERAL WELLS, TX 34 62 18 42 17 / 0 5 5 5 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/75
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
720 PM CST FRI JAN 3 2014
.UPDATE...
SEE DISCUSSION FOR EVENING UPDATE.
&&
.DISCUSSION...
CLEAR SKIES ACROSS MUCH OF THE CWA THIS EVENING HAS ALLOWED
TEMPERATURES TO DROP QUICKLY. A COUPLE OF RURAL LOCATIONS HAVE HAD
WINDS DECOUPLE WITH CURRENT TEMPERATURES SITTING AT JUST BELOW 40
DEGREES. STILL THINK ONSHORE WINDS WILL START TO SLOW DOWN THE
SLIDE IN TEMPERATURES THIS EVENING WITH THE WESTERN ZONES AND
COASTAL COUNTIES HAVING TEMPERATURES STARTING TO LEVEL OFF BEFORE
SUNRISE. GFS AND ECMWF ARE TO FAST WITH THE MOISTURE RETURN WHILE
THE RAP IS MORE ON TARGET. GIVEN THIS HAVE LEANED TOWARDS THE RAP.
BECAUSE OF THE TRENDS ABOVE HAVE UPDATED MIN T GRIDS. REST OF
FORECAST LOOKS ON TRACK. 23
&&
.PREV DISCUSSION... /ISSUED 546 PM CST FRI JAN 3 2014/
DISCUSSION...
UPDATED AVIATION DISCUSSION.
AVIATION...
CLEAR SKY WITH SOUTHEAST WIND AT ALL TAF SITES AT THE MOMENT. AS
ONSHORE FLOW CONTINUES WILL SEE AN INCREASE IN CLOUDS VERY LATE
TONIGHT AND SATURDAY WITH OVERCAST CONDITIONS EXPECTED SATURDAY
AFTERNOON MOST SITES. SOME UNCERTAINTY IN RESULTING CEILINGS BUT
THINK WILL MOSTLY START OUT VFR WITH CLOUD BASE AROUND 4000 FEET
THEN LOWER INTO MVFR RANGE DURING THE AFTERNOON. CLOUDS OVER THE
GULF NOW ARE IN THAT 4000 FOOT RANGE LENDING SOME SUPPORT TO THIS
AND GFS MOS GENERALLY SUPPORTS THIS SCENARIO AS WELL. SOME OF THE
OTHER MODEL FIELDS WOULD SUGGEST MVFR CIGS PERHAPS ARRIVING A
LITTLE EARLIER SO WILL HAVE TO MONITOR.
ONLY EXCEPTION TO ALL THE ABOVE IS CLL WHERE DID BITE ON SOME
LOWER MVFR CIGS AROUND SUNRISE SATURDAY BASED ON MAJORITY OF
GUIDANCE. 46
PREV DISCUSSION... /ISSUED 331 PM CST FRI JAN 3 2014/
DISCUSSION...
A HIGHLY AMPLIFIED PATTERN ALOFT WILL LEAD TO A PUSH OF A VERY
COLD AIR MASS INTO SE TX EARLY NEXT WEEK. THIS WILL BE PRECEDED BY
A WARMUP TONIGHT AND SATURDAY AS ONSHORE WINDS HELP RETURN GULF
MOISTURE TO THE AREA. STRONG WARM AIR ADVECTION ON SATURDAY WILL
LEAD TO ABOVE NORMAL HIGH TEMPERATURES. THE MODELS ARE THEN
CONSISTENT IN PUSHING A COLD FRONT QUICKLY THROUGH THE AREA SUNDAY
MORNING. THE FRONT IS EXPECTED TO BE OFF THE COAST BEFORE NOON.
THE COLDEST AIR MASS OF THE SEASON IS THEN EXPECTED. MODEL
GUIDANCE STILL DIFFERS...HOWEVER THERE IS ENOUGH CONSENSUS TO SAY
WITH CONFIDENCE THAT MOST AREAS WILL EXPERIENCE AT LEAST FREEZING
OVERNIGHT LOW TEMPERATURES SUNDAY NIGHT AND MONDAY MORNING TOWARD
THE COAST...WITH LOCATIONS ALONG AND NORTH OF A LINE FROM LIBERTY
TO THE WOODLANDS TO COLUMBUS EXPERIENCING MID 20S. MONDAY NIGHT
AND EARLY TUESDAY MORNING WILL LIKELY BE THE COLDEST NIGHT AS THE
CENTER OF THE SURFACE HIGH PRESSURE RIDGE SETTLES OVER THE INLAND
COUNTIES. LOWER 20S LOOKS LIKELY ALONG AND NORTH OF A LINE FROM
LIBERTY TO THE WOODLANDS TO COLUMBUS. METRO HOUSTON MAY SEE
TEMPERATURES FALL INTO THE MID 20S AND UPPER 20S...WITH HARRIS
COUNTY LIKELY EXPERIENCING LOWER 20S IN THE NORTHWEST...MID 20S IN
THE CENTRAL...AND UPPER 20S TOWARD GALVESTON BAY. LOWS BETWEEN 28
AND 32 LOOK TO BE COMMON ALONG THE IMMEDIATE COAST.
WINDS BY TUESDAY AFTERNOON WILL BECOME ONSHORE AND A COMBINATION
OF WARM AIR ADVECTION AND MOISTURE ADVECTION WILL LEAD TO A
WARMING TREND PROBABLY THE END OF THE WORK WEEK.
40
AVIATION...
DID NOT MAKE ANY MAJOR CHANGES WITH THE 18Z TAFS. ONSHORE WINDS HAVE
RETURNED AREAWIDE WITH ONLY HIGH CLOUDS MENTIONED. OTHERWISE VFR. 41
MARINE...
ONSHORE WINDS WILL CONTINUE TO DEVELOP ACROSS THE COASTAL WATERS DUR-
ING THE OVERNIGHT HRS AS HIGH PRESSURE MOVES INTO THE E/NE U.S.. NOT
A LOT OF ISSUES FOR THE MARINE AREAS UNTIL SUN WITH THE ARRIVAL/PASS-
AGE OF THE NEXT COLD FRONT. THIS IS SYSTEM IS EXPECTED TO BRING VERY
STRONG/GUSTY NORTH WINDS TO THE AREA AND SMALL CRAFT ADVISORIES WILL
LIKELY BE REQUIRED BY SUN AFTN. 41
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 38 66 48 50 23 / 0 10 20 10 0
HOUSTON (IAH) 36 66 58 58 27 / 0 10 30 30 0
GALVESTON (GLS) 43 64 58 58 34 / 0 10 20 30 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...23
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
624 PM CST FRI JAN 3 2014
.AVIATION...
/00Z TAFS/
WIND SPEEDS AND CIGS WILL BE THE MAIN THE CHALLENGE FIRST 12 HOURS
OF THE TAF CYCLE...THEN FROPA TIMING IN THE 24-30 HR PERIOD AT DFW
SATURDAY EVENING.
A SHORTWAVE WILL MOVE ACROSS AND PRODUCE SCATTERED CIRRUS OVERNIGHT
WITH SSE WINDS 10-15 KTS. BUFR AND RUC FORECAST SOUNDINGS ALL
INDICATE STRATUS RAPIDLY DEVELOPING AFTER MIDNIGHT AND MOVING UP
QUICKLY ON A 50 KT+ SSWLY LLJ. NAM/SREF/AND RUC ALL INDICATE
POTENTIAL FOR IFR BY 12Z...ESPECIALLY AT WACO. CONFIDENCE IS NOT
AS HIGH AT DFW METRO AIRPORTS AND WILL MAINTAIN LOW MVFR FOR NOW
WITH A TEMPO GROUP FOR IFR AROUND 12Z FOR WACO. BETTER CONFIDENCE
WILL LIKELY OCCUR WITH THE 06Z TAF ISSUANCE REGARDING IFR CIGS.
OTHERWISE...SOUTH WINDS 15-20 KTS DURING THE MORNING SATURDAY
WILL BECOME GUSTY BY MIDDAY...BEFORE VEERING WSWLY AHEAD OF A
FROPA IN THE DFW AREA BY 00Z SUNDAY. HAVE INTRODUCED A 24-30 HR
FORECAST PERIOD FOR THE ARRIVAL OF AN ARCTIC FRONT WITH WINDS
SHIFTING NORTHWEST NEAR 15 KTS. FROPA AT WACO WILL LIKELY OCCUR
AROUND 06Z SUNDAY OR AFTER.
05/
&&
.PREV DISCUSSION... /ISSUED 351 PM CST FRI JAN 3 2014/
A WARM AIR ADVECTION PATTERN WILL CONTINUE ACROSS THE REGION TONIGHT
THROUGH SATURDAY AS SURFACE LOW PRESSURE DEEPENS FROM THE NORTHERN
PLAINS TO THE SOUTHERN HIGH PLAINS. OVERNIGHT LOWS TONIGHT WILL BE
ABOVE FREEZING IN MOST LOCATIONS AND AFTERNOON HIGHS SATURDAY WILL
RANGE FROM THE MIDDLE 50S TO THE MIDDLE 60S. HOWEVER...THE WARM
WEATHER WILL BE SHORT-LIVED AS AN ARCTIC HIGH BUILDS SOUTHWARD
ACROSS THE PLAINS AND PUSHES A STRONG COLD FRONT ACROSS THE STATE.
THE FRONT SHOULD MOVE INTO THE NORTHWEST ZONES SATURDAY AFTERNOON
AND THROUGH THE ENTIRE FORECAST AREA SATURDAY NIGHT. THE FRONT
WILL BRING SHARPLY FALLING TEMPERATURES AND GUSTY NORTH WINDS.
THERE WILL BE A SLIGHT CHANCE OF RAIN NEAR THE FRONT SATURDAY
NIGHT...MAINLY ACROSS THE EASTERN COUNTIES...WHERE MOISTURE WILL
BE MOST ABUNDANT. TEMPERATURES SHOULD REMAIN ABOVE FREEZING WHERE
THE RAIN WILL FALL SATURDAY NIGHT SO NO FREEZING PRECIPITATION IS
EXPECTED.
EXTREMELY DRY AND COLDER AIR WILL PREVAIL ACROSS NORTH TEXAS ON
SUNDAY. HIGH TEMPERATURES WILL ONLY REACH THE UPPER 30S TO MIDDLE
40S. VERY COLD CONDITIONS WILL BEGIN SUNDAY NIGHT AND CONTINUE
THROUGH MONDAY AS SKIES CLEAR AND WINDS DECREASE. LOWS MONDAY
MORNING WILL RANGE FROM THE TEENS TO THE LOWER 20S WITH HIGHS
MONDAY FROM THE UPPER 20S IN THE NORTHWEST TO THE LOWER 40S IN THE
SOUTH.
IT WILL BE COLD AGAIN MONDAY NIGHT/TUESDAY MORNING WITH A
RELATIVELY LIGHT WIND...A CLEAR SKY AND DRY AIR IN PLACE. LOWS
TUESDAY MORNING WILL ONCE AGAIN BE IN THE TEENS AND 20S.
A RECOVERY FROM THE DRY AND COLD ARCTIC AIR WILL BEGIN ON TUESDAY
AS A SURFACE LEE TROUGH DEVELOPS AND THE GULF BEGINS TO OPEN UP.
THE GFS IS INDICATING THAT A FEW SHOWERS MAY DEVELOP OVERNIGHT TUESDAY
IN THE EAST...BUT THE ECMWF SOLUTION DOES NOT RECOVER THE
MOISTURE AS QUICKLY AND KEEPS PRECIP OUT OF NORTH TEXAS UNTIL WEDNESDAY.
THE ECMWF APPEARS TO BE A MORE REALISTIC SOLUTION WITH REGARDS TO THE
MOISTURE RETURN AFTER THE SCOURING BEHIND THE ARCTIC FRONT.
THEREFORE...WE WILL REMOVE ALL POPS FOR TUESDAY NIGHT. RAIN
CHANCES WILL INCREASE ON WEDNESDAY AS AN UPPER TROUGH APPROACHES
FROM THE WEST. THE BEST RAIN CHANCES WILL BE ACROSS THE EAST WHERE
MOISTURE WILL BE MOST ABUNDANT. MID LEVEL INSTABILITY LOOKS
INSUFFICIENT FOR THUNDER AT THIS TIME. RAIN CHANCES WILL CONTINUE
THROUGH THURSDAY AS A COLD FRONT MOVES INTO THE REGION. THE MODELS
HAVE BACKED OFF ON THE MOVEMENT OF THE UPPER TROUGH.
THEREFORE...THE COLD FRONT IS PROGGED TO STALL ACROSS THE REGION
THURSDAY AND LIFT BACK TO THE NORTH ON FRIDAY. WE HAVE DECIDED TO
KEEP SOME LOW POPS IN THE FORECAST THURSDAY THROUGH FRIDAY FOR
NOW AND AWAIT SOME MODEL CONSISTENCY AND AGREEMENT.
79
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 35 64 28 40 21 / 0 10 5 5 0
WACO, TX 40 64 32 42 21 / 0 10 10 5 0
PARIS, TX 30 56 34 34 14 / 5 10 20 5 5
DENTON, TX 37 61 26 37 16 / 0 10 5 5 0
MCKINNEY, TX 35 59 28 35 15 / 0 10 10 5 5
DALLAS, TX 39 61 31 40 19 / 0 10 10 5 5
TERRELL, TX 37 58 31 39 17 / 5 10 10 5 5
CORSICANA, TX 38 60 33 41 19 / 5 10 10 5 0
TEMPLE, TX 37 65 34 43 20 / 0 10 10 10 0
MINERAL WELLS, TX 34 62 18 42 17 / 0 5 5 5 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/79
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1132 PM CST WED JAN 1 2014
.AVIATION... /00Z TAF UPDATE/
MVFR CIGS OVER CENTRAL TX ARE DECREASING ALONG AND AHEAD OF THE
FRONT...WITH THE EARLY EVENING PRE-FRONTAL LOW CLOUDS RETREATING TO
THE SOUTHEAST. FRONTAL TIMING HAS SLOWED DOWN TO BE MORE ON TRACK
FOR A 7-830Z PASSAGE FOR THE TAF SITES. GUSTY N WINDS TO AROUND
25 KNOTS SHOULD RELAX AFTER 18Z THURSDAY.
&&
.PREV DISCUSSION... /ISSUED 305 PM CST WED JAN 1 2014/
SHORT TERM (TONIGHT THROUGH THURSDAY NIGHT)...
THIS AFTERNOON A PERSISTENT STRATOCU DECK WAS LOCATED EAST OF A LINE
FROM CARRIZO SPRINGS TO FREDERICKSBURG TO GEORGETOWN. THIS CLOUD DECK
WILL SLOWLY ERODE FROM WEST TO EAST THIS EVENING IN ADVANCE OF THE
COLD FRONT. AT 21Z THE COLD FRONT WAS LOCATED OVER THE TEXAS SOUTH
PLAINS MOVING SOUTHWARD. THE FRONT WILL ENTER THE HILL COUNTRY
BETWEEN 10 AND 11 PM THIS EVENING BASED ON THE LATEST RUC13 MODEL
SOLUTION. THIS WILL BE A DRY FROPA...HOWEVER A BRIEF PERIOD OF
PRE-FRONTAL PATCHY FOG IS POSSIBLE SOUTH AND EAST OF THE I-35
CORRIDOR WITH MORE WIDESPREAD FOG POSSIBLE ACROSS DIMMIT AND
SOUTHERN MAVERICK COUNTIES. POST-FRONTAL WINDS TONIGHT WILL BE
NORTHERLY AT 10 TO 20 MPH WITH GUSTS OF 30 MPH. LOWS THURSDAY
MORNING WILL RANGE FROM AROUND 30 ACROSS THE HILL COUNTRY TO NEAR
40 SOUTHWEST. THURSDAY WILL BE SUNNY AND COOLER AS CAA CONTINUES
THROUGHOUT THE DAY. HIGHS THURSDAY WILL BE 8 TO 12 DEGREES BELOW
NORMAL. GUSTY NORTHERLY WINDS WILL DIMINISH BY EVENING WITH THE
WEAKENING PRESSURE GRADIENT. GOOD RADIATIONAL COOLING WILL OCCUR
THURSDAY NIGHT INTO FRIDAY MORNING. THIS WILL RESULT IN A HARD
FREEZE FOR MUCH OF SOUTH CENTRAL TEXAS. THE LOW TEMP FCST FOR
THURSDAY NIGHT WILL BE A BLEND OF THE MET/MAV/ECMWF MOS GUIDANCE.
LONG TERM (FRIDAY THROUGH WEDNESDAY)...
BELOW NORMAL TEMPERATURES WILL CONTINUE NEXT WEEK DUE TO A SERIES
OF FROPAS. HOWEVER A BRIEF WARMING TREND WILL OCCUR FRIDAY AND
SATURDAY. HIGHS ON SATURDAY WILL BE IN LOWER 60S ACROSS THE HILL
COUNTRY WITH MID 60S ACROSS THE REMAINDER OF SOUTH CENTRAL TEXAS.
THE NEXT COLD FRONT WILL MOVE ACROSS THE REGION ON SUNDAY. ONCE
AGAIN AFTERNOON HIGHS WILL BE 5 TO 8 DEGREES BELOW NORMAL...RANGING
FROM THE UPPER 40S HILL COUNTRY TO NEAR 60 SOUTHWEST. LOW LEVEL
MOISTURE WILL BE LIMITED...WITH ONLY A SLIGHT CHANCE OF SHOWERS
FOR OUR EXTREME EASTERN COUNTIES. A RE-ENFORCEMENT OF THE COLD
AIRMASS WILL OCCUR ON TUESDAY WITH THE PASSAGE OF ANOTHER COLD
FRONT. WAA/OVERRUNNING/ISENTROPIC LIFT ON WEDNESDAY WILL LEAD TO
A SLIGHT CHANCE OF SHOWERS FOR MUCH OF THE REGION.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 36 52 29 53 40 / 0 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 33 51 24 52 35 / - 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 35 54 26 54 37 / 0 0 0 0 0
BURNET MUNI AIRPORT 31 49 24 52 37 / 0 0 0 0 0
DEL RIO INTL AIRPORT 36 55 30 55 38 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 31 50 24 52 39 / 0 0 0 0 0
HONDO MUNI AIRPORT 37 57 25 55 38 / 0 0 0 0 0
SAN MARCOS MUNI AIRPORT 35 52 26 54 37 / 0 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 36 51 28 53 41 / 10 0 0 0 0
SAN ANTONIO INTL AIRPORT 37 56 28 55 40 / 0 0 0 0 0
STINSON MUNI AIRPORT 39 57 29 56 41 / 0 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...18
SYNOPTIC/GRIDS...02
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
429 AM MST THU JAN 2 2014
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 427 AM MST THU JAN 2 2014
THE REGION WILL BE IN BETWEEN SYSTEMS TODAY AS A TRANSITORY RIDGE
MOVES OVERHEAD. STEEP INVERSION COURTESY OF A FRESH SNOWPACK HAVE
LED TO POCKETS OF FOG EARLY THIS MORNING. IN FACT A FEW SITES AT
DOUGLAS AND CHEYENNE HAVE SEEN VISIBILITIES FALL TO ONE QUARTER
MILE FOR A BRIEF TIME. 11-3.9 FOG PRODUCT OFF THE SATELLITE SHOWS
THESE AREA DIMINISHING...SO EXPECT THEIR DISSIPATION BY DAYBREAK.
MEANWHILE NEAR ARLINGTON...WINDS HAVE FLARED UP TO NEAR HIGH WIND
CRITERIA. A DESCENDING STABLE LAYER CONTRIBUTED TO THE SURFACING
OF STRONGER WINDS ALOFT. MODELS PROG THIS STABLE LAYER TO REACH
THE SURFACE THIS MORNING . SO ALTHOUGH WINDS WILL BREEZY IN
ARLINGTON TODAY...EXPECT THEM TO HAVE PEAKED EARLY THIS MORNING
AND REMAIN BELOW CRITERIA THROUGH THE REST OF THE DAYLIGHT HOURS.
OTHERWISE FLOW WILL BEGIN TO FLATTEN TODAY AHEAD OF THE NEXT
MODERATELY AMPLIFIED SHORTWAVE APPROACHING THE PACNW. EXPECT SKIES
TO BE PARTLY/MOSTLY SUNNY EARLY GIVING WAY TO INCREASING CLOUDS
FROM WEST TO EAST TOWARDS EVENING. AS FOR TEMPERATURES FAVORED THE
LOW SIDE OF GUIDANCE GIVEN YESTERDAYS SNOWFALL. LLVL WAA WILL
STILL BE ABLE TO BOOST TEMPS INTO THE 30S AND LOW 40S AREA WIDE
TODAY.
BY TONIGHT...LLVL GRADIENT BEGINS TO TIGHTEN ONCE AGAIN AHEAD OF
THE PACNW SHORTWAVE. H85/H7 KCAG-KCPR GRADIENTS CLIMB BETWEEN 60
AND 70 METERS LATE THIS EVENING AND CONTINUE THROUGH THE DAY ON
FRIDAY. H7 PROGS SHOW 70 KNOTS THROUGH THE PERIOD AS WELL. ONE
INHIBITING FACTOR WILL BE THE LACK OF APPRECIABLE UPPER-LEVEL
SUBSIDENT JET SUPPORT. EVEN SO...AM CONFIDENT ENOUGH WITH THE
GRADIENT LEVELS AND PROGD H7 WINDS TO UPGRADE THE INHERITED HIGH
WIND WATCH TO A WARNING AT WIND PRONE LOCATIONS. ALTHOUGH WINDS
WILL BE STRONG ALOFT AT ADJACENT LOCATIONS AS WELL...AM NOT
CONFIDENT THAT THESE WILL REACH THE SFC IN THE ABSENCE OF
SUBSIDENCE.
ANOTHER MOSTLY DRY DAY FOR FRIDAY. THE EXCEPTION WILL BE OVER
OROGRAPHICALLY FAVORED AREAS OF THE SNOWY AND SIERRA MADRE RANGES
WHERE MOISTURE WILL BEGIN ADVECTING IN AHEAD OF THE NEXT
APPROACHING SHORTWAVE. OTHERWISE...WILL JUST SEE A THICKER CLOUD
CANOPY MOVING INTO THE AREA. WILL BE A CHINOOK DAY EAST OF THE
LARAMIE RANGE AS ADIABATIC WARMING AND DRYING PRODUCES HIGH
TEMPERATURES THAT WILL CLIMB INTO THE 50S.
CHANGES BEGIN FRIDAY NIGHT AND SATURDAY...A SOUTHWARD MOVING COLD
FRONT WILL SPREAD SNOW OUT ONTO THE PLAINS AND INCREASES RATES
OVER THE HIER TERRAIN. CONFIDENCE IS GROWING FOR THE POTENTIAL FOR
A LOW-END WARNING EVENT OVER THE SNOWY/SIERRA MADRE RANGES FOR THE
LATE FRIDAY THROUGH SATURDAY TIMEFRAME. MODELS HAVE UNDERDONE
PRECIPITATION IN RECENT EVENTS IN THIS AREA AND WITH THIS
SHORTWAVE STRONGER IN COMPARISON...CAN FIND LITTLE REASON TO ARGUE
WITH BEING GENEROUS WITH MODEL OUTPUT. SO...HAVE ISSUED A WINTER
STORM WATCH FOR THE SNOWY/SIERRA MADRE RANGES FOR THIS PERIOD.
ADJACENT LOWER ELEVATIONS WILL LIKELY SEE ANOTHER 1 TO 3 INCHES
DURING THIS PERIOD. THE EXCEPTION WILL BE OVER THE WESTERN
NEBRASKA PANHANDLE WHERE ACCUMULATIONS WILL REMAIN BELOW AN INCH.
H7 TEMPERATURES WILL FALL TO AROUND -15C FOR SATURDAY. SO HIGHS
WILL ONLY REACH GENERALLY INTO THE 20S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 427 AM MST THU JAN 2 2014
OROGRAPHIC SNOW WILL CONTINUE ACROSS THE SIERRA MADRE AND SNOWY
RANGES ON SAT NIGHT IN MOIST NORTHWESTERLY FLOW ALOFT. THE UPPER
LEVEL JET ACROSS WESTERN WY WILL ALSO PROVIDE SOME LARGE SCALE
LIFT. THE MTN SNOW WILL LARGELY COME TO AN END BY SUN MORNING AS
THE JET SHIFTS EASTWARD. HIGHS ON SUN WILL BE COLD AS 700MB TEMPS
ARE AROUND -15C WITH WIDESPREAD CLOUD COVER ALSO. A STRONG
SHORTWAVE MOVING SOUTHWARD ACROSS THE DAKOTAS ON SUN WILL BRING A
FRONTAL SURGE AND REINFORCING SHOT OF VERY COLD AIR ACROSS THE
REGION BY THE AFTN AND NIGHT. THERE WILL BE A GOOD TEMP GRADIENT
OVER THE CWA BY SUN EVENING WITH 700MB TEMPS AT -15C IN RAWLINS AND
THE COLDEST AIR (700MB TEMPS OF -25C) OVER THE PANHANDLE. WIND
CHILL VALUES WILL APPROACH -30F OVER THE PANHANDLE ON SUN NIGHT.
STRONG SFC HIGH SLIDES EASTWARD OVER THE PLAINS ON MON WITH WINDS
BECOMING LIGHT SOUTHERLY BY THE AFTN. NOT EXPECTING A REAL
MODERATION IN TEMPS UNTIL TUES WHEN FLOW ALOFT BECOMES ZONAL AND A
LEE TROUGH DEVELOPS ACROSS THE PLAINS. THE MODELS HAVE A WEAK UPPER
LEVEL DISTURBANCE MOVING THROUGH UTAH/COLORADO BY LATE TUES AND WED
WHICH WILL INCREASE THE CHANCES OF OROGRAPHIC SNOW IN THE MTNS ONCE
AGAIN. NOT MUCH UPSLOPE OR LARGE SCALE SUPPORT FOR PRECIP SPREADING
OVER THE PLAINS. TEMPS WILL BE SEASONAL TO SLIGHTLY BELOW NORMAL
AFTER MON.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY EVENING)
ISSUED AT 942 PM MST WED JAN 1 2014
LATEST 11-3.9U SATELLITE IMAGERY SHOWING MOST OF SOUTHEAST WYOMING
FREE OF CLOUDS...BUT THERE IS SOME STRATUS BEING REPORTED UP BY
DOUGLAS. WITH A WESTERLY DOWNSLOPE WIND THOUGH...THINK CHANCES FOR
LOW CLOUDS/FOG WILL BE VERY LOCALIZED AND KEPT ALL AIRPORTS VFR
THROUGH THE NEXT 24 HOURS. LATEST HRRR MODEL RUN SUPPORTS THIS
DECISION AS WELL.
&&
.FIRE WEATHER...
ISSUED AT 427 AM MST THU JAN 2 2014
FIRE WEATHER CONCERNS WILL BE MINIMAL FOR THE FORESEEABLE FUTURE.
A DRIER AND WARMER PERIOD TAKING SHAPE FOR TODAY AND TOMORROW...AS
HIGH TEMPERATURES RETURN INTO THE 50S FOR SOME AREAS EAST OF THE
LARAMIE RANGE. STRONG WINDS WILL MAKE A RETURN TO PORTIONS OF
SOUTHEAST WYOMING TONIGHT AND FRIDAY. A HIGH WIND WARNING HAS BEEN
ISSUED FOR AREAS AROUND THE SOUTHERN LARAMIE RANGE AND NEAR
ARLINGTON. THE NEXT FRONT WILL BRING ANOTHER ROUND OF ACCUMULATING
SNOW LATE FRIDAY THROUGH SATURDAY. MOUNTAINS ARE EXPECTED TO
RECEIVE ANOTHER FOOT OF ACCUMULATION WITH THIS SYSTEM. MEANWHILE
LOWER ELEVATIONS WILL LIKELY ONLY SEE A COUPLE OF INCHES. A COLDER
WEEKEND AHEAD AS HIGHS ONLY REACH INTO THE TEENS AND 20S.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY
AFTERNOON FOR WYZ112-114.
HIGH WIND WARNING FROM 6 PM THIS EVENING TO MIDNIGHT MST FRIDAY
NIGHT FOR WYZ106-110-116-117.
NE...NONE.
&&
$$
SHORT TERM...HAHN
LONG TERM...FINCH
AVIATION...CLAYCOMB
FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
952 PM MST WED JAN 1 2014
.UPDATE...
ISSUED AT 942 PM MST WED JAN 1 2014
LATEST 00Z MODEL GUIDANCE SHOWING THE RETURN OF STRONG WINDS...AT
LEAST FOR OUR WIND PRONE AREAS AND POSSIBLY A LITTLE MORE
WIDESPREAD TOMORROW NIGHT. LATEST WRKHGT PRODUCT SHOWING CRAIG TO
CASPER 850/700MB HEIGHT GRADIENTS INCREASING TO TO 57/53 MTRS BY
06Z TOMORROW NIGHT...LASTING THROUGH AT LEAST 00Z SATURDAY. LATEST
00Z 700MB WINDS OVER SOUTHEAST WYOMING INCREASING TO 50KTS
TOMORROW NIGHT...UP TO 70KTS FRIDAY AFTERNOON. WENT AHEAD AND
ISSUED A HIGH WIND WATCH FOR THE WIND PRONE AREAS TOMORROW NIGHT.
LATEST MAV MOS WINDS FOR CHEYENNE...LARAMIE AND RAWLINS ALSO
HINTING THAT THIS COULD BE A MORE WIDESPREAD HIGH WIND EVENT.
RAWLINS INCREASES TO 30KTS FRIDAY AFTERNOON...LARAMIE 29KTS AND
CHEYENNE...27KTS. UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 300 PM MST WED JAN 1 2014
AREA OF COOLER CLOUD TOPS WITH ASSOCIATED LIGHT SNOW PROGRESSING
SOUTH OVER THE SOUTHERN PORTION OF THE CWA EARLY THIS AFTERNOON.
EXPECT THIS AREA TO MOVE SOUTH OUT OF THE CWA BY EARLY THIS
EVENING WITH SOME CLEARING ACROSS THE CWA OVERNIGHT. NNW UPPER
FLOW WILL HOLD OVER THE CWA INTO THURSDAY THEN GRADUALLY BACK TO
NWLY THEN WESTERLY THURSDAY NIGHT THROUGH FRIDAY AHEAD OF THE NEXT
UPPER TROF WHICH WILL MOVE INTO THE NRN ROCKYS BY LATE FRIDAY. AS
THIS OCCURS LEE TROFFING WILL DEVELOP AND DEEPEN OVER THE HIGH
PLAINS THURSDAY AND HOLD THROUGH FRIDAY WITH RESULTANT DOWNSLOPE
FLOW ALLOWING FOR MILDER TEMPERATURES. WILL UNDERCUT GUIDANCE SOME
FOR TEMPS ESPECIALLY THURSDAY DUE TO SNOW COVER DEPOSITED TODAY.
OTHER CONCERN WILL BE FOR POTENTIAL STRONG WINDS OVER THE WIND
PRONE AREAS FRIDAY AHEAD OF THE APPROACHING UPPER SYSTEM. 700MB
WINDS LOOK TO INCREASE TO OVER 50KTS BY FRIDAY AFTERNOON AND
PERSIST INTO EARLY EVENING BEFORE DIMINISHING. MAY NEED A HILITE
BUT WILL SEE WHAT LATER PROGS DEPICT. OTHERWISE MAINLY DRY ACROSS
THE CWA THOUGH SOME SNOW SHOWERS SHOULD INCREASE OVER THE HIGHER
MTNS BY LATE FRIDAY AS MOISTURE INCREASES AND RIDES UP THE WEST SLOPES.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 300 PM MST WED JAN 1 2014
FRIDAY NIGHT/SATURDAY...NEXT POSITIVELY TILTED SHORTWAVE TROUGH
ALOFT MOVES ACROSS WYOMING AND COLORADO...SPREADING LIGHT TO
MODERATE...AND OCCASIONALLY HEAVY SNOW ACROSS OUR COUNTIES. BASED ON
PROJECTED MOISTURE DEPTH ALONG WITH LIFT PROVIDED BY
DYNAMICS...OROGRAPHICS...UPSLOPE AND CYCLONIC CURVATURE
ALOFT...EXPECT MOST AREAS TO AT LEAST SEE A DUSTING OF SNOW...WITH
50 TO 100 PERCENT POPS AT MOST LOCATIONS...ESPECIALLY THE TERRAIN
FAVORED UPSLOPE LOCATIONS SUCH AS THE EASTERN SLOPES OF THE
LARAMIE RANGE FROM WHEATLAND TO CHEYENNE. BY LATE SATURDAY
AFTERNOON...THE BULK OF THE AREAL SNOW COVERAGE WILL HAVE MOVED
INTO COLORADO ALONG WITH THE PRIMARY DYNAMICS OF THE SHORTWAVE
TROUGH ALOFT.
SUNDAY...NEXT POLAR EXPRESS ARRIVES WITH ALL MODELS SHOWING STRONG
ARCTIC AIR INTRUSION...WHICH WILL QUITE LIKELY SPREAD LIGHT SNOW
ACROSS OUR COUNTIES WITH MINIMAL ACCUMULATION DUE TO THE LIMITED
MOISTURE WITH THESE TYPES OF ARCTIC INTRUSIONS. WOULD NOT BE
SURPRISED TO SEE MAXIMUM TEMPERATURES ONLY IN THE SINGLE DIGITS AND
TEENS BASED ON THE PROJECTED THICKNESSES AND 700 MB TEMPERATURES
NEAR -24 CELSIUS...THUS LATER SHIFTS MAY NEED TO LOWER OUR HIGH
TEMPERATURES.
MONDAY...ARCTIC COLD AIR PROGGED TO REMAIN ENTRENCHED UNDER BRISK
NORTH NORTHWEST FLOW ALOFT. MAXIMUM TEMPERATURES IN THE SINGLE
DIGITS AND MOSTLY TEENS BASED ON 700 MB TEMPERATURES STILL NEAR -16
CELSIUS. NO SNOWFALL DUE TO MINIMAL LOW AND MID LEVEL MOISTURE
AVAILABILITY AND MINIMAL LIFT.
TUESDAY...FLOW ALOFT BACKS TO WEST AND WEAKENS. WITH THE DENSE AND
COLD ARCTIC AIRMASS ENTRENCHED...AND WITH RELATIVELY WEAK WEST FLOW
ALOFT...BELIEVE ARCTIC AIR WILL BUDGE VERY LITTLE...THUS MAXIMUM
TEMPERATURES STILL BELOW FREEZING AT MOST LOCALES...THOUGH WITH
TEMPERATURES MODERATING AS 700 MB TEMPERATURES WARM TO NEAR -6
CELSIUS.
WEDNESDAY...MODELS SIMILAR IN DEPICTION OF A WEAK...LOW AMPLITUDE
SHORTWAVE TROUGH ALOFT MOVING ACROSS OUR COUNTIES WITH THE BULK OF
THE SNOW REMAINING TO OUR SOUTH OVER COLORADO...THOUGH WILL PAINT
SOME LOW OROGRAPHIC SNOWS ACROSS OUR NORTHERN LARAMIE...SNOWY AND
SIERRA MADRE RANGES...AND DRY ELSEWHERE. ARCTIC AIR WILL RETREAT TO
OUR EAST...ALLOWING DOWNSLOPE CHINOOK WINDS TO MODERATE TEMPERATURES
WITH MAXIMUMS ABOVE FREEZING AT MOST LOCATIONS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY EVENING)
ISSUED AT 942 PM MST WED JAN 1 2014
LATEST 11-3.9U SATELLITE IMAGERY SHOWING MOST OF SOUTHEAST WYOMING
FREE OF CLOUDS...BUT THERE IS SOME STRATUS BEING REPORTED UP BY
DOUGLAS. WITH A WESTERLY DOWNSLOPE WIND THOUGH...THINK CHANCES FOR
LOW CLOUDS/FOG WILL BE VERY LOCALIZED AND KEPT ALL AIRPORTS VFR
THROUGH THE NEXT 24 HOURS. LATEST HRRR MODEL RUN SUPPORTS THIS
DECISION AS WELL.
&&
.FIRE WEATHER...
ISSUED AT 300 PM MST WED JAN 1 2014
NO SIGNIFICANT CONCERNS SEEN THROUGH THE WEEKEND WITH MAINLY NON-
CRITICAL CONDITIONS. AREAS OF GUSTY WINDS WILL RETURN BY LATE
THURSDAY AND CONTINUE INTO FRIDAY AHEAD OF NEXT COLD FRONT WHICH
SHOULD PASS ACROSS THE REGION SATURDAY BRINGING MUCH COLDER
TEMPERATURES. LINGERING LIGHT SNOW NEAR THE COLORADO BORDER THIS
EVENING THEN MAINLY DRY UNTIL SATURDAY WHEN SOME LIGHT SNOWS
EXPECTED AGAIN BEHIND THE COLD FRONT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WATCH FROM THURSDAY EVENING THROUGH FRIDAY EVENING FOR
WYZ106-110-116-117.
NE...NONE.
&&
$$
UPDATE...CLAYCOMB
SHORT TERM...RE
LONG TERM...RUBIN
AVIATION...CLAYCOMB
FIRE WEATHER...RE
AREA FORECAST DISCUSSION...CORRECTED
NWS NEW YORK NY
427 AM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE SLIDES OFFSHORE THROUGH TONIGHT. LOW PRESSURE TRACKS
FROM THE GULF COAST STATES SUNDAY...INTO QUEBEC BY
MONDAY...DRAGGING ITS POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC
HIGH PRESSURE THEN BUILDS IN THROUGH WEDNESDAY...THEN SLIDES
OFFSHORE WEDNESDAY NIGHT. A COLD FRONT CROSSES THE AREA
THURSDAY...FOLLOWED BY HIGH PRESSURE BUILDING IN ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH ASSOCIATED
SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER FAR EASTERN
ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS BEGINS TO BUILD
IN LATE IN THE AFTERNOON.
BRUTALLY COLD TO GET STARTED WITH INTERIOR ZONES AND PINE BARRENS
HAVING LOWS -10 TO -15...AND FROM 0 TO -10 ELSEWHERE - EXCEPT FROM
-5 TO 5 ABOVE IN NYC. WILL CONTINUE WITH SPS HIGHLIGHTING COLD
TEMPERATURES EARLY. FORTUNATELY WINDS GENERALLY LESS THAN 5 MPH -
SO NO WIND CHILLS TO COMPOUND THINGS.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED SW
FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-ZL IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION OF THE AFD FOR
DETAILS ON AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAUGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -10 TO -20...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD OVERHEAD THIS MORNING...AND THEN MOVE EAST
LATER TODAY.
VFR WITH MAINLY MID AND HIGH CLOUDS EXPECTED. LIGHT WINDS THIS
MORNING WILL BECOME SW AND INCREASE TO AROUND 10 KT THIS AFTERNOON.
.OUTLOOK FOR 06Z SUN THROUGH WED...
.LATE TONIGHT-SUNDAY MORNING...POSSIBLE MVFR OR LOWER CONDS WITH
PATCHY FOG AND FREEZING DRIZZLE.
.SUNDAY AFTERNOON...MVFR OR LOWER CONDITIONS AT TIMES IN LIGHT RAIN.
.SUNDAY NIGHT-MON MORNING...IFR CONDITIONS LIKELY IN RAIN. LLWS WITH
S WINDS 50 KT AT FL015.
.MON AFTERNOON-TUE...CONDITIONS IMPROVING TO VFR. W WINDS
G25-30KT...THEN 30-35 KT TUE AFTERNOON.
.WED...VFR. W WINDS G20KT.
&&
.MARINE...
SCA CONTINUES FOR THE OCEAN WATERS AS SEAS AT 44017 ARE STILL 6 FT
DUE TO INCOMING SE SWELL. THESE SWELLS SHOULD DROP BELOW 5 FT THIS
MORNING...BUT THEN INCREASING SW FLOW SHOULD BUILD OCEAN SEAS BACK
TO 5 FT BY LATE DAY OUT EAST...AND ON MOST IF NOT ALL OCEAN WATERS
TONIGHT. STEADY SE-S FLOW 15-20 KT SHOULD THEN MAINTAIN SCA CONDS ON
THE OCEAN ESPECIALLY OUT EAST INTO MON MORNING.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 -4
ISLIP...NY 10 2008 -5
LAGUARDIA...NY 4 1981 3
JFK AIRPORT...NY 8 1981 1
NYC-CENTRAL PARK...NY -3 1918 3
NEWARK...NJ 1 1981 -1
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
ANZ355.
SMALL CRAFT ADVISORY UNTIL 6 AM EST MONDAY FOR ANZ350.
SMALL CRAFT ADVISORY UNTIL 9 AM EST THIS MORNING FOR ANZ353.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MALOIT
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...GOODMAN
MARINE...GOODMAN
HYDROLOGY...MALOIT
CLIMATE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
425 AM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE SLIDES OFFSHORE THROUGH TONIGHT. LOW PRESSURE TRACKS
FROM THE GULF COAST STATES SUNDAY...INTO QUEBEC BY
MONDAY...DRAGGING ITS POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC
HIGH PRESSURE THEN BUILDS IN THROUGH WEDNESDAY...THEN SLIDES
OFFSHORE WEDNESDAY NIGHT. A COLD FRONT CROSSES THE AREA
THURSDAY...FOLLOWED BY HIGH PRESSURE BUILDING IN ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH ASSOCIATED
SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER FAR EASTERN
ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS BEGINS TO BUILD
IN LATE IN THE AFTERNOON.
BRUTALLY COLD TO GET STARTED WITH INTERIOR ZONES AND PINE BARRENS
HAVING LOWS -10 TO -15...AND FROM 0 TO -10 ELSEWHERE - EXCEPT FROM
-5 TO 5 ABOVE IN NYC. WILL CONTINUE WITH SPS HIGHLIGHTING COLD
TEMPERATURES EARLY. FORTUNATELY WINDS GENERALLY LESS THAN 5 MPH -
SO NO WIND CHILLS TO COMPOUND THINGS.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED SW
FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-ZL IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION OF THE AFD FOR
DETAILS ON AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAUGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -5 TO -15...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD OVERHEAD THIS MORNING...AND THEN MOVE EAST
LATER TODAY.
VFR WITH MAINLY MID AND HIGH CLOUDS EXPECTED. LIGHT WINDS THIS
MORNING WILL BECOME SW AND INCREASE TO AROUND 10 KT THIS AFTERNOON.
.OUTLOOK FOR 06Z SUN THROUGH WED...
.LATE TONIGHT-SUNDAY MORNING...POSSIBLE MVFR OR LOWER CONDS WITH
PATCHY FOG AND FREEZING DRIZZLE.
.SUNDAY AFTERNOON...MVFR OR LOWER CONDITIONS AT TIMES IN LIGHT RAIN.
.SUNDAY NIGHT-MON MORNING...IFR CONDITIONS LIKELY IN RAIN. LLWS WITH
S WINDS 50 KT AT FL015.
.MON AFTERNOON-TUE...CONDITIONS IMPROVING TO VFR. W WINDS
G25-30KT...THEN 30-35 KT TUE AFTERNOON.
.WED...VFR. W WINDS G20KT.
&&
.MARINE...
SCA CONTINUES FOR THE OCEAN WATERS AS SEAS AT 44017 ARE STILL 6 FT
DUE TO INCOMING SE SWELL. THESE SWELLS SHOULD DROP BELOW 5 FT THIS
MORNING...BUT THEN INCREASING SW FLOW SHOULD BUILD OCEAN SEAS BACK
TO 5 FT BY LATE DAY OUT EAST...AND ON MOST IF NOT ALL OCEAN WATERS
TONIGHT. STEADY SE-S FLOW 15-20 KT SHOULD THEN MAINTAIN SCA CONDS ON
THE OCEAN ESPECIALLY OUT EAST INTO MON MORNING.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 -4
ISLIP...NY 10 2008 -5
LAGUARDIA...NY 4 1981 3
JFK AIRPORT...NY 8 1981 1
NYC-CENTRAL PARK...NY -3 1918 3
NEWARK...NJ 1 1981 -1
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
ANZ355.
SMALL CRAFT ADVISORY UNTIL 6 AM EST MONDAY FOR ANZ350.
SMALL CRAFT ADVISORY UNTIL 9 AM EST THIS MORNING FOR ANZ353.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MALOIT
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...GOODMAN
MARINE...GOODMAN
HYDROLOGY...MALOIT
CLIMATE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
348 AM CST SAT JAN 4 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CST SAT JAN 4 2014
WE ARE SEEING THE FIRST SIGNS OF THE COLD OUTBREAK SET TO ARRIVE
THIS WEEKEND...WITH TEMPERATURES ACROSS WEST CENTRAL MINNESOTA
HAVING PLUMMETED FROM THE MID 30S/LOWER 40S TO THE SINGLE DIGITS
WITHIN THE LAST 9 HOURS...COMPLIMENTS OF NORTHWEST WINDS AT 25 TO 35
MPH /GUSTING TO AROUND 45 MPH/. THE WINTRY MIX OF PRECIPITATION THAT
WAS ENDURED ACROSS MUCH OF CENTRAL AND SOUTHWEST MN FRIDAY EVENING
DID A NUMBER ON ROAD CONDITIONS...PER THE MNDOT 511 MAP.
ADDITIONALLY...NORTHWEST WINDS WILL CONTINUE TO YIELD AREAS OF
BLOWING SNOW IN THOSE SAME AREAS THIS MORNING. WILL THEREFORE EXTEND
THE WINTER WEATHER ADVISORY ACROSS THE WEST FOR A FEW HOURS PAST
DAYBREAK...WHERE THE EFFECTS OF BLOWING SNOW WILL LIKELY BE
GREATER THIS MORNING.
TEMPERATURES WILL CONTINUE TO FALL THROUGHOUT THE DAY...WITH BELOW
ZERO READINGS LIKELY ACROSS MUCH OF WESTERN MN BY MID
AFTERNOON...AND NEARLY THE ENTIRE FORECAST AREA BY 00Z. WIND CHILL
READINGS WILL LOITER AROUND -25 TODAY...BUT WILL FOCUS ON
HIGHLIGHTING THE ARRIVAL OF THE MORE DANGEROUS SURGE OF COLD AIR
THIS EVENING/TONIGHT...KEEPING THE START TIME OF THE WIND CHILL
WARNING AT 00Z SUNDAY. WIND CHILL READINGS WILL DIP TO BETWEEN 35
AND 45 BELOW BY DAYBREAK SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 348 AM CST SAT JAN 4 2014
THE INCREDIBLE...HISTORIC COLD OUTBREAK IS STILL ON TRACK FOR THE
FIRST HALF OF THE LONG TERM PERIOD WITH VERY HIGH CONFIDENCE ALL
AROUND. GUIDANCE IS SLIGHTLY COLDER THAN YESTERDAY...BUT STILL IN
THE GENERAL BALLPARK OF WHAT WE HAVE BEEN CALLING FOR. NAM/GEM ARE
THE COLDEST SOLUTIONS ALOFT WHILE GFS/ECMWF ARE COLDEST AT THE
SURFACE SUNDAY AND MONDAY. THE COLDEST 850 MB TEMP RECORDED AT
MPX/STC WAS -39.3C ON 1/10/1982. THE 06Z NAM AND 00Z GEM BRING THE
-37C/-36C CONTOUR ACROSS THE MSP METRO SUNDAY NIGHT WHILE
GFS/ECMWF ARE MORE IN THE -32 TO -34C RANGE. REGARDLESS...CERTAINLY
SOME RARE AIR. THEREFORE...NOT OVERLY CONCERNED ABOUT OUR CHANCES
TO APPROACH OR EXCEED RECORDS...CLOUD COVER PRESENT OR
NOT...AND STRONG WINDS PRESENT OR NOT.
THE FIRST LOBE OF BITTER COLD AIR WILL ALREADY BE IN PLACE AT THE
START OF THE PERIOD...WITH A SECONDARY COLD FRONT SINKING SOUTH
SUNDAY AFTERNOON. AS IF TEMPS WEREN/T TOO COLD ENOUGH THEY WILL
LIKELY CONTINUE TO FALL SUNDAY AFTERNOON AND LEAD TO THE COLDEST
PERIOD IN ALMOST TWO DECADES SUNDAY NIGHT. HIGHS WILL BE IN THE
LOW TO MID TEENS BELOW ZERO EARLY AFTERNOON BEFORE FALLING TO 20
TO 25 BELOW EARLY EVENING. AS THE MOST INTENSE CHUNK OF AIR
ROTATES THROUGH LATE SUNDAY NIGHT...TEMPS SHOULD BE ABLE TO FALL
ANOTHER 10 DEGREES OR SO IN MOST LOCATIONS AND BOTTOM OUT BETWEEN
25 AND 35 BELOW EARLY MONDAY MORNING. STRONG WEST WINDS BETWEEN 15
AND 20 MPH /GUSTS TO 30 MPH/ WILL DRIVE WIND CHILLS DOWN INTO THE
55 TO 65 BELOW RANGE. SLOW MODERATION WILL OCCUR MONDAY...BUT
HIGHS WILL STRUGGLE TO GET MUCH WARMER THAN 20 BELOW WITH DAYTIME
WIND CHILLS HOVERING BETWEEN 45 AND 55 BELOW. STRONG WAA ALOFT
WILL PREVENT TEMPS FROM PLUMMETING TOO MUCH MONDAY NIGHT. BY
TUESDAY...TEMPS WILL RECOVER TO A MORE ACCEPTABLE COLD OUTBREAK
LEVEL. DID NOT CHANGE TOO MUCH ON THIS SHIFT...ALTHOUGH DID LOWER
TEMPS A TICK OR TWO IN SPOTS SUNDAY THROUGH MONDAY PER LATEST
GUIDANCE TRENDS.
MODELS DIFFER A BIT ON HOW QUICKLY TO PUSH THE ARCTIC AIR OUT.
GEM IS THE MOST AGGRESSIVE WITH -20S FOR LOWS THROUGH WEDNESDAY
NIGHT. THIS MAY VERY WELL OCCUR IN THE LIGHT WIND REGIME UNDER
HIGH PRESSURE. FEEL THE GFS AND ECMWF ARE TOO WARM IN THIS
SCENARIO AND HAVE TRENDED DOWNWARD A BIT FROM THE PREVIOUS
FORECAST.
STRONGER SOUTHERLY FLOW WILL ESTABLISH ITSELF LATE NEXT WEEK WITH
MUCH MILDER CONDITIONS RETURNING. HIGHS IN THE 30S AND POSSIBLY
LOW 40S APPEAR IN THE OFFING NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1119 PM CST FRI JAN 3 2014
BAND OF PCPN CURRENTLY MOVING THROUGH ALONG/AHEAD OF FRONTAL
BOUNDARY. PCPN-TYPE IS A MIXED BAG GIVEN ABOVE FREEZING AIR
ALOFT... WITH SLEET... FREEZING RAIN... AND SNOW OCCURRING. THE
GENERAL TREND WILL BE FOR THINGS TO TRANSITION TO LIGHT SNOW AND
END WITHIN THE NEXT FEW HOURS FROM WEST TO EAST. WINDS WILL BE
SHIFTING TO THE WEST AND NORTHWEST... AND WE/LL HAVE SOME MVFR
CEILINGS AROUND INTO SATURDAY MORNING. THERE REMAINS SOME QUESTION
AS TO HOW QUICKLY WE/LL LOSE THE LOW CEILINGS AS THE ARCTIC AIR
STARTS TO MOVE IN... WITH THE NAM AND RAP SUGGESTING QUITE A BIT
MORE BOUNDARY LAYER RH IN COMPARISON TO THE GFS. WILL REMAIN
OPTIMISTIC GIVEN THE OVERALL ABSOLUTE DRYNESS OF THE AIRMASS...
AND ALLOW FOR THINGS TO SCATTER OUT ON SATURDAY. ALSO REMOVED
QUITE A BIT OF THE BLOWING SNOW... SINCE MUCH OF IT WAS COVERED UP
BY SLEET AND FREEZING RAIN AND SHOULD BE TOUGHER TO BLOW AROUND.
HOWEVER... THAT IS CERTAINLY SOMETHING WHICH COULD STILL BE AN
ISSUE IF THE ASSUMPTION THERE IS NOTHING TO BLOW AROUND IS
INCORRECT.
KMSP...PRIMARY UNCERTAINTIES ARE WILL CEILINGS THROUGH SATURDAY
MORNING AND WHETHER WE/LL SEE MUCH BELOW 017 FT AGL... AND ALSO
IF/WHEN THINGS WILL SCATTER OUT. THE MIXED PCPN ONGOING SHOULD BE
ENDING WITHING A FEW HOURS.
/OUTLOOK FOR KMSP/
SATURDAY OVERNIGHT...VFR. NORTHWEST WIND 10 TO 15 KT.
SUNDAY...MVFR CEILINGS POSSIBLE LATE. NORTHWEST WIND 10 TO 20 KT.
SUNDAY NIGHT...MVFR CEILINGS EXPECTED. NORTHWEST WIND 10 TO 15 KT.
MONDAY...MVFR CEILINGS EXPECTED EARLY. NORTHWEST WIND 10 TO 20 KT.
MONDAY NIGHT...VFR. WEST WIND 5 TO 15 KT.
TUESDAY...VFR. WEST WIND 5 TO 10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
MNZ043>045-050>053-059>063-066>070-075>078-083>085-092-093.
WIND CHILL WARNING FROM 6 PM THIS EVENING TO NOON CST TUESDAY
FOR MNZ041>045-047>070-073>078-082>085-091>093.
WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR MNZ041-
042-047>049-054>058-064-065-073-074-082-091.
WI...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
WIZ014>016-023>028.
WIND CHILL WARNING FROM 6 PM THIS EVENING TO NOON CST TUESDAY
FOR WIZ014>016-023>028.
&&
$$
SHORT TERM...LS
LONG TERM...BORGHOFF
AVIATION...
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1126 PM CST FRI JAN 3 2014
.UPDATE...
ISSUED AT 1119 PM CST FRI JAN 3 2014
UPDATED TO INCLUDE 06Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 328 PM CST FRI JAN 3 2014
BEFORE THE MAIN SURGE OF EXTREMELY COLD AIR ARRIVES OVER THE
WEEKEND...A STRONG STORM SYSTEM AHEAD OF THIS AIR MASS HAS MODIFIED
ENOUGH TO PRODUCE A PERIOD OF FREEZING RAIN AND SLEET THIS EVENING
AS IT MOVES FROM THE WESTERN DAKOTAS...EASTWARD ACROSS THE UPPER
MIDWEST OVERNIGHT. REGIONAL RADAR ALSO ALREADY INDICATED A LARGE
AREA OF PRECIPITATION DEVELOPING ACROSS CENTRAL ND...SOUTHWARD INTO
CENTRAL SD. ABV THE SFC...TEMPS HAVE WARMED SIGNIFICANTLY...WITH 85H
TEMPS NEAR +6C IN WC MN TO NEAR 0C IN EC MN. HOWEVER...IN THE LOWEST
1-2K...TEMPS WERE NEAR -10C IN EC MN...TO -4C IN WC MN. THE DEPTH OF
THE COLDER TEMPS IN EASTERN MN WILL ALLOW FOR MAINLY SLEET AND SOME
-SN. HOWEVER...FURTHER TO THE WEST...THE PRECIPITATION HAS A BETTER
CHC OF HOLDING AS LIQUID AND NOT REFREEZING IN THE FORM OF SLEET.
THEREFORE...A BETTER CHC OF FREEZING RAIN IS EXPECTED IN WC MN
DURING THE EVENING HRS BEFORE THE ARCTIC FRONT ARRIVES AFT MIDNIGHT.
DEPENDING UPON HOW MUCH FURTHER THE WARMER AIR ADVECTS TO THE
EAST...WILL DEPEND IF EASTERN MN GETS MORE FREEZING RAIN OR SLEET.
WC WI WILL LIKELY REMAIN SNOW OR A MIXTURE OF SLEET AND SNOW. QPF
AMTS REMAIN FAIRLY LIGHT...BUT EVEN A FEW HUNDREDTHS OF AN INCH OF
FREEZING RAIN CAN CAUSE HAZARDOUS ROADS IF NOT TREATED. A WINTER WX
ADV WAS ISSUED BASED ON THE FREEZING PRECIPITATION AND THEN BLOWING
AND DRIFTING SNOW AFTER MIDNIGHT. ONLY SMALL CHGS IN THE FORECAST ON
SATURDAY AS TEMPS WILL CONTINUE TO FALL THROUGHOUT THE DAY. WIND
CHILL VALUES BY LATE SATURDAY AFTERNOON WILL RANGE FROM -30 TO -35F
IN CENTRAL/WC MN...TO AROUND -15 IN WC WI.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 328 PM CST FRI JAN 3 2014
THE WORST ARCTIC OUTBREAK SO FAR THIS COLD SEASON WILL BE UNDERWAY
AT THE START OF THE LONG TERM. DETERMINISTIC SOLUTIONS CONTINUE TO
DRIVE A POLAR VORTEX... CURRENTLY OVER THE YUKON... TO NEAR KDLH BY
SUNDAY EVENING... WITH 1000-500MB THICKNESS VALUES BELOW 486
(DAM). VERTICAL PROFILES BETWEEN THE SURFACE AND 850MB SHOW
TEMPERATURES IN THE -30 TO -35 DEG C RANGE ACROSS THE CWA SUNDAY
NIGHT AND MONDAY. THIS UPCOMING COLD IS QUITE SIMILAR PATTERN-WISE TO
THAT IN EARLY JANUARY 1982. A CHECK ON WEATHER MAPS DURING THAT
COLD OUTBREAK SHOWED THE UPPER LOW BOTTOMING OUT ACROSS THE UPPER
GREAT LAKES ALONG WITH THE SURFACE HIGH STAYING WELL WEST AND
SOUTH OF THE FA. THIS RESULTS IN THE LIKELYHOOD OF SOME CLOUDINESS
DUE TO PROXIMITY OF THE UPPER LOW AND ALSO A NW WIND FROM 10 TO
20 MPH IN THE HEART OF THE ARCTIC COLD. MSP DURING THE COLD WAVE
IN EARLY JANUARY 1982 HAD A LOW TEMPERATURES OF -26 DEG F. IN
FACT...LOWS ACROSS THE ENTIRE FA REACHED -25 TO -32 DEG F. THIS IS
VERY SIMILAR THE FORECAST VALUES AHEAD.
TODAY/S FORECAST HAS LOWS DROPPING BELOW ZERO SATURDAY EVENING AND
NOT RISING ABOVE ZERO UNTIL WEDNESDAY. THIS IS A RUN OF 88 HOURS
BELOW ZERO FOR MSP. NOT A TOP 10 RECORD... WHICH RUNS FROM 186
HOURS DOWN TO 130 HOURS. THE WORST STRETCH OF COLD IS FROM SUNDAY
NIGHT THROUGH TUESDAY. LOWS SUNDAY NIGHT ARE FORECAST IN THE -25
TO -32 DEG F RANGE... WITH -27 FOR MSP (THIS WOULD TIE THE RECORD).
THIS WOULD ALSO BE THE COLDEST MSP HAS BEEN SINCE DECEMBER 26TH
1996. THE ECE AND GFS MOS FOR MSP ARE -27 AND -29 DEG F
RESPECTIVELY. THEN HAVE THE POTENTIAL FOR RECORD LOW HIGHS ON
MONDAY WITH VALUES ONLY FORECAST IN THE -14 TO -20 DEG F RANGE. WE
HAVE MSP AT -17 FOR THE HIGH ON MONDAY WHICH WOULD BE A RECORD LOW
HIGH (-14). MONDAY NIGHT WE ARE BACK DOWN IN THE -20 TO -26 DEG F
RANGE WITH HIGHS ON TUESDAY IN THE SINGLE DIGITS BELOW ZERO.
AS MENTIONED EARLIER...NW WINDS WILL BE BLOWING THE WHOLE TIME.
WIND CHILL VALUES SUNDAY NIGHT AND MONDAY WILL BE IN THE -50 TO
-60 DEG F RANGE WITH VALUES MONDAY NIGHT AND TUESDAY MORNING IN
THE -40 TO -50 DEG F RANGE. A WIND CHILL WARNING REMAINS IN EFFECT
FROM 6 PM SATURDAY UNTIL NOON ON TUESDAY.
THE BALANCE OF THE WORKWEEK WILL BE ONE OF TEMPERATURE MODERATION
AS THE FLOW BECOMES MORE WESTERLY. HIGHS INCREASE FROM THE SINGLE
DIGITS ABOVE ZERO ON WEDNESDAY TO THE UPPER 20S BY FRIDAY. THERE
IS SOME DISAGREEMENT BETWEEN THE GFS/GEM AND EC ON HOW CLOSE WE
WILL BE TO A SOUTHERN STREAM SNOW EVENT. THE GEM AND GFS WOULD
JUST NICK OUR EASTERN AND SOUTHERN AREAS WHILE THE EC WOULD BRING
THE SNOW THROUGH A NORTHERN STREAM FEATURE. COLLABORATION TODAY
WAS TO KEEP VERY SMALL POPS CONFINED TO AREAS EAST AND SOUTH OF
THE TWIN CITIES FOR WEDNESDAY/WEDNESDAY NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1119 PM CST FRI JAN 3 2014
BAND OF PCPN CURRENTLY MOVING THROUGH ALONG/AHEAD OF FRONTAL
BOUNDARY. PCPN-TYPE IS A MIXED BAG GIVEN ABOVE FREEZING AIR
ALOFT... WITH SLEET... FREEZING RAIN... AND SNOW OCCURRING. THE
GENERAL TREND WILL BE FOR THINGS TO TRANSITION TO LIGHT SNOW AND
END WITHIN THE NEXT FEW HOURS FROM WEST TO EAST. WINDS WILL BE
SHIFTING TO THE WEST AND NORTHWEST... AND WE/LL HAVE SOME MVFR
CEILINGS AROUND INTO SATURDAY MORNING. THERE REMAINS SOME QUESTION
AS TO HOW QUICKLY WE/LL LOSE THE LOW CEILINGS AS THE ARCTIC AIR
STARTS TO MOVE IN... WITH THE NAM AND RAP SUGGESTING QUITE A BIT
MORE BOUNDARY LAYER RH IN COMPARISON TO THE GFS. WILL REMAIN
OPTIMISTIC GIVEN THE OVERALL ABSOLUTE DRYNESS OF THE AIRMASS...
AND ALLOW FOR THINGS TO SCATTER OUT ON SATURDAY. ALSO REMOVED
QUITE A BIT OF THE BLOWING SNOW... SINCE MUCH OF IT WAS COVERED UP
BY SLEET AND FREEZING RAIN AND SHOULD BE TOUGHER TO BLOW AROUND.
HOWEVER... THAT IS CERTAINLY SOMETHING WHICH COULD STILL BE AN
ISSUE IF THE ASSUMPTION THERE IS NOTHING TO BLOW AROUND IS
INCORRECT.
KMSP...PRIMARY UNCERTAINTIES ARE WILL CEILINGS THROUGH SATURDAY
MORNING AND WHETHER WE/LL SEE MUCH BELOW 017 FT AGL... AND ALSO
IF/WHEN THINGS WILL SCATTER OUT. THE MIXED PCPN ONGOING SHOULD BE
ENDING WITHING A FEW HOURS.
/OUTLOOK FOR KMSP/
SATURDAY OVERNIGHT...VFR. NORTHWEST WIND 10 TO 15 KT.
SUNDAY...MVFR CEILINGS POSSIBLE LATE. NORTHWEST WIND 10 TO 20 KT.
SUNDAY NIGHT...MVFR CEILINGS EXPECTED. NORTHWEST WIND 10 TO 15 KT.
MONDAY...MVFR CEILINGS EXPECTED EARLY. NORTHWEST WIND 10 TO 20 KT.
MONDAY NIGHT...VFR. WEST WIND 5 TO 15 KT.
TUESDAY...VFR. WEST WIND 5 TO 10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL 3 AM CST SATURDAY FOR MNZ041>045-
047>070-073>078-082>085-091>093.
WIND CHILL WARNING FROM 6 PM SATURDAY TO NOON CST TUESDAY FOR
MNZ041>045-047>070-073>078-082>085-091>093.
WI...WINTER WEATHER ADVISORY UNTIL 3 AM CST SATURDAY FOR WIZ014>016-
023>028.
WIND CHILL WARNING FROM 6 PM SATURDAY TO NOON CST TUESDAY FOR
WIZ014>016-023>028.
&&
$$
UPDATE...
SHORT TERM...JLT
LONG TERM...RAH
AVIATION...
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
238 AM CST SAT JAN 4 2014
.SYNOPSIS...
ISSUED AT 237 AM CST SAT JAN 4 2014
THE ARCTIC FRONT AS OF 08Z HAD MOVED THROUGH MITCHELL
SD...VALENTINE AND SCOTTSBLUFF NE. A 1-2 HOUR SURGE IN WIND SPEEDS
BEHIND THE FRONT RESULTING IN GUSTS UP TO 35 KTS. TEMPERATURES IN
NEBRASKA RANGE FROM 27 AT VTN TO 40 AT ALBION. EARLIER RADAR
RETURNS HAVE MOSTLY DISAPPEARED IN WESTERN NEBR. LOOKING FOR
TEMPERATURES IN CENTRAL AND SWRN NEBR TO WARM TO AROUND 40
DEGREES IN THE NEXT FEW HOURS BEFORE COOLING BACK INTO THE UPPER
20S TOWARD 12Z.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 237 AM CST SAT JAN 4 2014
MUCH COLDER AIR WILL SWEEP INTO WESTERN NEBRASKA TODAY BEHIND THE ARCTIC
FRONT. EARLY MORNING HIGHS ALL AREAS. TEMPERATURES TO FALL INTO
THE MID TEENS ACROSS THE NCTRL BY LATE AFTERNOON. THERE IS A SLIGHT
CHANCE FOR SNOW ACROSS FAR SWRN AREAS TODAY WHICH WILL BE ON THE
NORTHERN PERIPHERY OF SUPPORTED SNOW AREA ACROSS COLORADO INTO WRN
AND CNTRL KANSAS.
FOR TONIGHT...LOW CHC POPS NEAR 30 PERCENT MAINLY WEST OF HWY 83
WITH A SLIGHT CHANCE INTO EASTERN ZONES AFTER MIDNIGHT. BEST AREA
OF FRONTOGENESIS ACROSS NRN WYOMING INTO SWRN SD WILL WEAK AND
TRANSLATE SOUTHEASTWARD INTO WESTERN NEBRASKA OVERNIGHT. WHILE MOST
AREA MAY ONLY SEE A DUSTING...WILL NEED TO MONITOR MODEL TRENDS
AS THE NAM SHOWING SNOW AMOUNTS AROUND 1 INCH IN THE EASTERN
PANHANDLE. WHILE VERY COLD TEMPERATURES WILL OCCUR OVERNIGHT FROM
NEAR ZERO NCTRL TO THE UPPER SINGLE DIGITS FAR SOUTHWEST. LOWEST
WIND CHILLS TO FALL TO NEAR 15 BELOW...WHICH SHOULD REMAIN BELOW
WIND CHILL ADVISORY LEVELS. THE MUCH COLDER AIR WILL ADVANCE
THROUGH CENTRAL SOUTH DAKOTA BY 12Z SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 237 AM CST SAT JAN 4 2014
LOW PRESSURE DEVELOPING ON THE HIGH PLAINS WILL MOVE INTO SOUTHWEST
NEBRASKA AND THEN SOUTH INTO WESTERN KANSAS SUNDAY. THIS WILL GIVE A
BRIEF PERIOD IN WHICH SNOW SHOWERS COULD DEVELOP AS WARMER AIR LIFTS
UP OVER THE COLD BOUNDARY LAYER. FRONTOGENESIS IS ALSO LIKELY IN THE
270-285K LAYER AS THE SHORT WAVE TROUGH PIVOTS THROUGH THE AREA.
AS THE LOW SLIPS SOUTH...A REINFORCING SHOT OF ARCTIC AIR WILL POUR
INTO NEBRASKA. STILL...IT APPEARS THAT WESTERN NEBRASKA WILL BE ON
THE WESTERN EDGE OF THE COLDEST AIR WHILE THE COLDEST AIR SETTLES
INTO THE UPPER MIDWEST...THE EASTERN DAKOTAS AND MINNESOTA. IT
WILL CERTAINLY BE VERY COLD IN CENTRAL AND WESTERN NEBRASKA WITH
TEMPERATURES SUNDAY FROM AROUND ZERO IN VALENTINE AND ONEILL TO
THE LOWER TEENS IN THE EXTREME SOUTHWEST. LOWS SUNDAY NIGHT AND
EARLY MONDAY WILL BE BELOW ZERO OVER ALL OF NORTH CENTRAL TO
SOUTHWEST NEBRASKA WITH THE COLDEST AIR IN NORTH CENTRAL AND
NORTHWEST NEBRASKA. TEMPERATURES WILL BE SLIGHTLY HIGHER MONDAY
AND MONDAY NIGHT WITH A FAIRLY STRONG RECOVERY TO NEAR AVERAGE
TEMPERATURES TUESDAY THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1116 PM CST FRI JAN 3 2014
IT LOOKS LIKE MVFR SHOULD BECOME FAIRLY WIDESPREAD ONCE THE ARCTIC
FRONT CURRENTLY MOVING THROUGH WRN SD SWEEPS INTO THE FCST AREA
OVERNIGHT. THE RAP AND NAM MODELS HOLD THIS STRATUS IN PLACE
THROUGHOUT THE DAY SATURDAY WHILE THE GEM...GFS AND ECM MIX THESE
CLOUDS OUT. THE FORECAST SIDES WITH THE LATTER 3 MODELS FOR A MIX
OF MVFR AND VFR SATURDAY.
NOTE THAT LAPSE RATES WILL REMAIN QUITE STEEP SUPPORTING THE
DEVELOPMENT OF ISOLATED TO SCATTERED SNOW SHOWER COVERAGE
OVERNIGHT THROUGH SATURDAY EVENING WHICH COULD PRODUCE LOCAL IFR
CONDITIONS...MAINLY ALONG AND WEST OF HIGHWAY 61.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY MORNING
FOR NEZ004>010-022>029-035>038-094.
&&
$$
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...SPRINGER
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1144 PM CST FRI JAN 3 2014
.SYNOPSIS...
ISSUED AT 313 PM CST FRI JAN 3 2014
H5 ANALYSIS THIS MORNING HAS A TANDEM OF LOW PRESSURES
OVER CANADA. THE FIRST OVER NORTHERN QUEBEC...AND A SECOND OVER
NORTHERN PORTIONS OF THE NORTHWEST TERRITORIES OF CANADA. RIDGING
HAS BUILT FROM THE GULF OF ALASKA INTO EASTERN ALASKA AND THE YUKON.
ACROSS THE WESTERN CONUS...A STRONG SHORTWAVE TROUGH WAS PRESENT
OVER THE PACIFIC NORTHWEST...WITH 150+ METER HT FALLS NOTED OVER
EASTERN WASHINGTON STATE...SERN BRITISH COLUMBIA INTO SWRN
SASKATCHEWAN. ACROSS THE SRN 2/3RDS OF THE CONUS...BROAD WEST
NORTHWESTERLY FLOW WAS PRESENT WITH PACIFIC AIR PUSHING INTO THE
CENTRAL AND SRN PLAINS THIS AFTERNOON. AT THE SURFACE...LOW PRESSURE
WAS PRESENT OVER NORTHWESTERN ND WITH A WARM FRONT EXTENDING SWD
INTO EASTERN NEBRASKA. A COLD FRONT EXTENDED TO THE WEST NORTHWEST
OF THIS FEATURE WITH MUCH COLDER AIR BEGINNING TO PUSH INTO NORTHERN
MT OVER THE PAST COUPLE OF HRS. AS OF 2 PM CST...UNDER PARTLY CLOUDY
SKIES...TEMPERATURES RANGED FROM 41 AT O`NEILL TO 63 AT IMPERIAL.
&&
.UPDATE...
ISSUED AT 1142 PM CST FRI JAN 3 2014
THE WINDS SWEEPING THROUGH SD LOOK PRETTY STRONG AND THE HRRR
SHOWS GUSTS TO 50 MPH AS THE FRONT SWINGS THROUGH PARTS OF
NORTHERN NEBRASKA TONIGHT. A WIND ADVISORY IS IN PLACE UNTIL 6 AM
CST FOR THIS FAST MOVING FRONT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 313 PM CST FRI JAN 3 2014
COLD FRONT NUMBER ONE WILL ARRIVE TONIGHT BRINGING AN END TO THE
UNSEASONABLY WARM TEMPERATURES. THE FRONT WILL BEGIN TO IMPACT THE
AREA AFTER 00Z WITH SOME LIGHT RAIN/SNOW POSSIBLE ACROSS THE FAR NW
AS TEMPS INITIALLY NEAR FREEZING. TEMPS QUICKLY FALL BELOW ZERO AND
PRECIP TYPE BECOMES ALL SNOW. MOISTURE IS LIMITED WITH MODEL RH
GENERALLY LESS THAN 70 PERCENT FOR ANY GIVEN MID/UPPER LAYER. THE
NAM/RUC RETAIN THE BEST MOISTURE...GENERALLY IN THE BL...AND CLOUDS
INCREASED FOR STRATUS. LIFT IS MARGINALLY AND TOWARDS THE TOP OF THE
DENDRITIC GROWTH ZONE. SNOW CHANCES...ALBEIT SLIGHT AND WITH LOW
CONFIDENCE...CONTINUE ACROSS THE NW ZONES INTO THE EASTERN PANHANDLE
OVERNIGHT. LITTLE IF ANY ACCUMULATION EXPECTED. THE COLD AIR
ADVECTION WILL MAKE IT DIFFICULT TO WARM UP TOMORROW. ALSO EXPECT
SOME STRATUS TO SPREAD ACROSS THE AREA...THUS MORNING HIGHS ARE
LIKELY FOR MOST AREAS...WITH STEADY OF FALLING FOR THE AFTERNOON.
NORTH WINDS BEHIND THE FRONT WILL BE BREEZY AND WIND CHILLS FALL
INTO THE SINGLE DIGITS...AND SOME AREAS UP NORTH...SINGLE DIGITS
BELOW ZERO. UPPER LEVEL WAVE/SUPPORT TO SLIDE ACROSS KS...AND MAY
BRING SOME SN INTO FAR SW NEB...AROUND THE IMPERIAL TO HAYES CENTER
AREA...AGAIN LOW CONFIDENCE WITH BEST SUPPORT SOUTH OF THE CWA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 312 PM CST FRI JAN 3 2014
SATURDAY NIGHT THROUGH MONDAY...MAIN FORECAST CHALLENGES
ARE TEMPERATURES...DANGEROUS WIND CHILLS AND LIGHT SNOW IN
ASSOCIATION WITH AN ARCTIC FRONT. FOR SATURDAY NIGHT PIECE ONE OF
THE ARCTIC AIR WILL PUSH SOUTHWEST INTO THE PANHANDLE AND WESTERN CWA
SATURDAY EVENING SETTING UP A BAROCLINIC ZONE ACROSS THE WESTERN HALF
OF THE CWA. ADDITIONAL SUPPORT FOR LIGHT SNOW WILL ARRIVE OVERNIGHT
AS THE LEFT FRONT QUAD OF THE JET LIFTS EAST ACROSS THE NORTHERN
ROCKIES. CROSS SECTIONS THROUGH THE EASTERN PANHANDLE AND WESTERN
CWA INDICATE DECENT MOISTURE BELOW 700MB WHICH IS COLLOCATED WITH
DECENT LIFT IN THE DENDRITIC ZONE SATURDAY EVENING. WITH MOISTURE
AND DYNAMICS IN PLACE...WILL CONTINUE TO MENTION CHANCES FOR LIGHT
SNOW SATURDAY NIGHT ROUGHLY WEST OF HIGHWAY 83. ON SUNDAY...THE MAIN
SHOT OF ARCTIC AIR WILL PUSH INTO THE FORECAST AREA SOMETIME DURING
THE LATE MORNING/EARLY AFTERNOON HOURS. AS THE ARCTIC AIR PUSHES
SOUTHWARD SUNDAY...STILL CANNOT RULE OUT SOME LIGHT SNOW IN
ASSOCIATION WITH THE ARCTIC FROPA AND WILL CONTINUE TO MENTION IT.
TEMPERATURES WILL BE TRICKY SUNDAY GIVEN THE TIMING OF THE
FRONT...AS HIGHS WILL OCCUR DURING THE MORNING IN THE NORTH AND
AROUND MIDDAY IN THE SOUTH. ON SUNDAY AFTERNOON STRONG COLD AIR
ADVECTION...WILL INCREASE NORTHERLY WINDS WHICH WILL COMBINE WITH
THE BITTERLY COLD AIR TO PRODUCE WIND CHILLS RANGING FROM 20 TO 40
BELOW ZERO SUNDAY EVENING. THESE READINGS MAY DIP TO BELOW 40 BELOW
IN THE NORTH BY 12Z MONDAY. DECIDED TO HOIST A WIND CHILL WATCH
ALONG AND NORTH OF HIGHWAY 92 FROM MIDDAY SUNDAY THROUGH MIDDAY
MONDAY...AS WIND CHILLS OF 30 TO 45 BELOW ZERO APPEAR POSSIBLE IN
THESE AREAS. COLD TEMPERATURES WILL CARRY OVER INTO MONDAY...HOWEVER
WINDS ARE EXPECTED TO BEGIN TO RELAX MONDAY AFTERNOON AS HIGH
PRESSURE BEGINS TO BUILD SOUTH INTO THE MISSOURI VALLEY.
TEMPERATURES MONDAY MORNING WILL RANGE FROM -15 IN THE NORTH TO
AROUND -3 IN FAR SWRN NEBRASKA. READINGS WILL REBOUND BACK TO THE
SINGLE DIGITS AND TEENS MONDAY AFTERNOON AS THE CORE OF THE ARCTIC AIR IS
SHOVED EAST INTO THE MISSISSIPPI VALLEY AND UPPER MIDWEST.
MONDAY NIGHT THROUGH FRIDAY...THE MID RANGE MODEL SOLUTIONS CONTINUE
TO HINT AT A PATTERN SHIFT NEXT WEEK...TO A MORE ZONAL PATTERN. THIS
WILL ALLOW WARMER PACIFIC AIR TO INFILTRATE THE WESTERN AND CENTRAL
CONUS...LEADING TO NORMAL TO ABOVE NORMAL TEMPERATURES NEXT WEEK.
THE ONE DAY WITH SLIGHTLY COOLER TEMPS WILL BE WEDNESDAY AS A
DISTURBANCE AND WEAK FRONTAL BOUNDARY PUSHES THROUGH THE NORTHERN
PLAINS. THIS WILL BE A GLANCING BLOW OF ARCTIC AIR...SO ITS IMPACTS
ON TEMPS WILL BE FAIRLY MINIMAL. H85 TEMPS WEDNESDAY THROUGH FRIDAY
WILL GENERALLY RANGE FROM ZERO TO 5C...SO HIGHS WILL GENERALLY BE IN
THE 30S WITH SOME 40S OVER SWRN NEBRASKA. DRY CONDS WILL CONTINUE IN
THE EXTENDED AS NO SIGNIFICANT CUTOFF SYSTEMS OR DISTURBANCES WILL
TRACK ACROSS THE CENTRAL PLAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1116 PM CST FRI JAN 3 2014
IT LOOKS LIKE MVFR SHOULD BECOME FAIRLY WIDESPREAD ONCE THE ARCTIC
FRONT CURRENTLY MOVING THROUGH WRN SD SWEEPS INTO THE FCST AREA
OVERNIGHT. THE RAP AND NAM MODELS HOLD THIS STRATUS IN PLACE
THROUGHOUT THE DAY SATURDAY WHILE THE GEM...GFS AND ECM MIX THESE
CLOUDS OUT. THE FORECAST SIDES WITH THE LATTER 3 MODELS FOR A MIX
OF MVFR AND VFR SATURDAY.
NOTE THAT LAPSE RATES WILL REMAIN QUITE STEEP SUPPORTING THE
DEVELOPMENT OF ISOLATED TO SCATTERED SNOW SHOWER COVERAGE
OVERNIGHT THROUGH SATURDAY EVENING WHICH COULD PRODUCE LOCAL IFR
CONDITIONS...MAINLY ALONG AND WEST OF HIGHWAY 61.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 6 AM CST /5 AM MST/ SATURDAY FOR NEZ004>010-
026>029-094.
WIND CHILL WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY MORNING
FOR NEZ004>010-022>029-035>038-094.
&&
$$
UPDATE...CDC
SYNOPSIS...CLB
SHORT TERM...MASEK
LONG TERM...CLB
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1117 PM CST FRI JAN 3 2014
.SYNOPSIS...
ISSUED AT 313 PM CST FRI JAN 3 2014
H5 ANALYSIS THIS MORNING HAS A TANDEM OF LOW PRESSURES
OVER CANADA. THE FIRST OVER NORTHERN QUEBEC...AND A SECOND OVER
NORTHERN PORTIONS OF THE NORTHWEST TERRITORIES OF CANADA. RIDGING
HAS BUILT FROM THE GULF OF ALASKA INTO EASTERN ALASKA AND THE YUKON.
ACROSS THE WESTERN CONUS...A STRONG SHORTWAVE TROUGH WAS PRESENT
OVER THE PACIFIC NORTHWEST...WITH 150+ METER HT FALLS NOTED OVER
EASTERN WASHINGTON STATE...SERN BRITISH COLUMBIA INTO SWRN
SASKATCHEWAN. ACROSS THE SRN 2/3RDS OF THE CONUS...BROAD WEST
NORTHWESTERLY FLOW WAS PRESENT WITH PACIFIC AIR PUSHING INTO THE
CENTRAL AND SRN PLAINS THIS AFTERNOON. AT THE SURFACE...LOW PRESSURE
WAS PRESENT OVER NORTHWESTERN ND WITH A WARM FRONT EXTENDING SWD
INTO EASTERN NEBRASKA. A COLD FRONT EXTENDED TO THE WEST NORTHWEST
OF THIS FEATURE WITH MUCH COLDER AIR BEGINNING TO PUSH INTO NORTHERN
MT OVER THE PAST COUPLE OF HRS. AS OF 2 PM CST...UNDER PARTLY CLOUDY
SKIES...TEMPERATURES RANGED FROM 41 AT O`NEILL TO 63 AT IMPERIAL.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 313 PM CST FRI JAN 3 2014
COLD FRONT NUMBER ONE WILL ARRIVE TONIGHT BRINGING AN END TO THE
UNSEASONABLY WARM TEMPERATURES. THE FRONT WILL BEGIN TO IMPACT THE
AREA AFTER 00Z WITH SOME LIGHT RAIN/SNOW POSSIBLE ACROSS THE FAR NW
AS TEMPS INITIALLY NEAR FREEZING. TEMPS QUICKLY FALL BELOW ZERO AND
PRECIP TYPE BECOMES ALL SNOW. MOISTURE IS LIMITED WITH MODEL RH
GENERALLY LESS THAN 70 PERCENT FOR ANY GIVEN MID/UPPER LAYER. THE
NAM/RUC RETAIN THE BEST MOISTURE...GENERALLY IN THE BL...AND CLOUDS
INCREASED FOR STRATUS. LIFT IS MARGINALLY AND TOWARDS THE TOP OF THE
DENDRITIC GROWTH ZONE. SNOW CHANCES...ALBEIT SLIGHT AND WITH LOW
CONFIDENCE...CONTINUE ACROSS THE NW ZONES INTO THE EASTERN PANHANDLE
OVERNIGHT. LITTLE IF ANY ACCUMULATION EXPECTED. THE COLD AIR
ADVECTION WILL MAKE IT DIFFICULT TO WARM UP TOMORROW. ALSO EXPECT
SOME STRATUS TO SPREAD ACROSS THE AREA...THUS MORNING HIGHS ARE
LIKELY FOR MOST AREAS...WITH STEADY OF FALLING FOR THE AFTERNOON.
NORTH WINDS BEHIND THE FRONT WILL BE BREEZY AND WIND CHILLS FALL
INTO THE SINGLE DIGITS...AND SOME AREAS UP NORTH...SINGLE DIGITS
BELOW ZERO. UPPER LEVEL WAVE/SUPPORT TO SLIDE ACROSS KS...AND MAY
BRING SOME SN INTO FAR SW NEB...AROUND THE IMPERIAL TO HAYES CENTER
AREA...AGAIN LOW CONFIDENCE WITH BEST SUPPORT SOUTH OF THE CWA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 312 PM CST FRI JAN 3 2014
SATURDAY NIGHT THROUGH MONDAY...MAIN FORECAST CHALLENGES
ARE TEMPERATURES...DANGEROUS WIND CHILLS AND LIGHT SNOW IN
ASSOCIATION WITH AN ARCTIC FRONT. FOR SATURDAY NIGHT PIECE ONE OF
THE ARCTIC AIR WILL PUSH SOUTHWEST INTO THE PANHANDLE AND WESTERN CWA
SATURDAY EVENING SETTING UP A BAROCLINIC ZONE ACROSS THE WESTERN HALF
OF THE CWA. ADDITIONAL SUPPORT FOR LIGHT SNOW WILL ARRIVE OVERNIGHT
AS THE LEFT FRONT QUAD OF THE JET LIFTS EAST ACROSS THE NORTHERN
ROCKIES. CROSS SECTIONS THROUGH THE EASTERN PANHANDLE AND WESTERN
CWA INDICATE DECENT MOISTURE BELOW 700MB WHICH IS COLLOCATED WITH
DECENT LIFT IN THE DENDRITIC ZONE SATURDAY EVENING. WITH MOISTURE
AND DYNAMICS IN PLACE...WILL CONTINUE TO MENTION CHANCES FOR LIGHT
SNOW SATURDAY NIGHT ROUGHLY WEST OF HIGHWAY 83. ON SUNDAY...THE MAIN
SHOT OF ARCTIC AIR WILL PUSH INTO THE FORECAST AREA SOMETIME DURING
THE LATE MORNING/EARLY AFTERNOON HOURS. AS THE ARCTIC AIR PUSHES
SOUTHWARD SUNDAY...STILL CANNOT RULE OUT SOME LIGHT SNOW IN
ASSOCIATION WITH THE ARCTIC FROPA AND WILL CONTINUE TO MENTION IT.
TEMPERATURES WILL BE TRICKY SUNDAY GIVEN THE TIMING OF THE
FRONT...AS HIGHS WILL OCCUR DURING THE MORNING IN THE NORTH AND
AROUND MIDDAY IN THE SOUTH. ON SUNDAY AFTERNOON STRONG COLD AIR
ADVECTION...WILL INCREASE NORTHERLY WINDS WHICH WILL COMBINE WITH
THE BITTERLY COLD AIR TO PRODUCE WIND CHILLS RANGING FROM 20 TO 40
BELOW ZERO SUNDAY EVENING. THESE READINGS MAY DIP TO BELOW 40 BELOW
IN THE NORTH BY 12Z MONDAY. DECIDED TO HOIST A WIND CHILL WATCH
ALONG AND NORTH OF HIGHWAY 92 FROM MIDDAY SUNDAY THROUGH MIDDAY
MONDAY...AS WIND CHILLS OF 30 TO 45 BELOW ZERO APPEAR POSSIBLE IN
THESE AREAS. COLD TEMPERATURES WILL CARRY OVER INTO MONDAY...HOWEVER
WINDS ARE EXPECTED TO BEGIN TO RELAX MONDAY AFTERNOON AS HIGH
PRESSURE BEGINS TO BUILD SOUTH INTO THE MISSOURI VALLEY.
TEMPERATURES MONDAY MORNING WILL RANGE FROM -15 IN THE NORTH TO
AROUND -3 IN FAR SWRN NEBRASKA. READINGS WILL REBOUND BACK TO THE
SINGLE DIGITS AND TEENS MONDAY AFTERNOON AS THE CORE OF THE ARCTIC AIR IS
SHOVED EAST INTO THE MISSISSIPPI VALLEY AND UPPER MIDWEST.
MONDAY NIGHT THROUGH FRIDAY...THE MID RANGE MODEL SOLUTIONS CONTINUE
TO HINT AT A PATTERN SHIFT NEXT WEEK...TO A MORE ZONAL PATTERN. THIS
WILL ALLOW WARMER PACIFIC AIR TO INFILTRATE THE WESTERN AND CENTRAL
CONUS...LEADING TO NORMAL TO ABOVE NORMAL TEMPERATURES NEXT WEEK.
THE ONE DAY WITH SLIGHTLY COOLER TEMPS WILL BE WEDNESDAY AS A
DISTURBANCE AND WEAK FRONTAL BOUNDARY PUSHES THROUGH THE NORTHERN
PLAINS. THIS WILL BE A GLANCING BLOW OF ARCTIC AIR...SO ITS IMPACTS
ON TEMPS WILL BE FAIRLY MINIMAL. H85 TEMPS WEDNESDAY THROUGH FRIDAY
WILL GENERALLY RANGE FROM ZERO TO 5C...SO HIGHS WILL GENERALLY BE IN
THE 30S WITH SOME 40S OVER SWRN NEBRASKA. DRY CONDS WILL CONTINUE IN
THE EXTENDED AS NO SIGNIFICANT CUTOFF SYSTEMS OR DISTURBANCES WILL
TRACK ACROSS THE CENTRAL PLAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1116 PM CST FRI JAN 3 2014
IT LOOKS LIKE MVFR SHOULD BECOME FAIRLY WIDESPREAD ONCE THE ARCTIC
FRONT CURRENTLY MOVING THROUGH WRN SD SWEEPS INTO THE FCST AREA
OVERNIGHT. THE RAP AND NAM MODELS HOLD THIS STRATUS IN PLACE
THROUGHOUT THE DAY SATURDAY WHILE THE GEM...GFS AND ECM MIX THESE
CLOUDS OUT. THE FORECAST SIDES WITH THE LATTER 3 MODELS FOR A MIX
OF MVFR AND VFR SATURDAY.
NOTE THAT LAPSE RATES WILL REMAIN QUITE STEEP SUPPORTING THE
DEVELOPMENT OF ISOLATED TO SCATTERED SNOW SHOWER COVERAGE
OVERNIGHT THROUGH SATURDAY EVENING WHICH COULD PRODUCE LOCAL IFR
CONDITIONS...MAINLY ALONG AND WEST OF HIGHWAY 61.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY MORNING
FOR NEZ004>010-022>029-035>038-094.
&&
$$
SYNOPSIS...CLB
SHORT TERM...MASEK
LONG TERM...CLB
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1129 PM CST FRI JAN 3 2014
.DISCUSSION...
UPDATED AVIATION.
&&
.AVIATION...
LATEST SATELLITE IMAGERY SHOWS CLEAR SKY WITH JUST A FEW 4000 FOOT
CLOUDS COMING IN OFF THE GULF. SOME OF THESE COULD CREEP INTO LBX
AND GLS OVERNIGHT AS THEY ADVECT NORTHWARD GIVEN ONSHORE LOW LEVEL
FLOW. MODEL SOUNDINGS AND MOS GUIDANCE SUGGEST POSSIBILITY OF
MVFR CEILING DEVELOPMENT VERY LATE TONIGHT AND SATURDAY MORNING
FOR AT LEAST NORTHERN TAF SITES...INCLUDING CLL...UTS AND
CXO...AND HAVE INCLUDED THIS SCENARIO FOR THOSE LOCATIONS.
ELSEWHERE EXPECT A GENERAL INCREASE IN CLOUD COVER MAINLY ON
SATURDAY WITH BROKEN TO OVERCAST CONDITIONS BY MIDDAY. CLOUD
HEIGHT STILL DIFFICULT TO CALL...AS EXPECT SOMEWHERE ON THE 3000
TO 4000 FOOT RANGE FOR MOST PART...TRENDING LOWER AS SATURDAY
AFTERNOON AND EVENING EVOLVE. SOME OF THE GUIDANCE AND MODEL
SOUNDINGS WOULD ARGUE FOR LOWER CEILINGS RIGHT AWAY...BUT THIS
GUIDANCE CAN BE OVERLY PESSIMISTIC AT TIMES. 46
&&
.PREV DISCUSSION... /ISSUED 720 PM CST FRI JAN 3 2014/
UPDATE...
SEE DISCUSSION FOR EVENING UPDATE.
DISCUSSION...
CLEAR SKIES ACROSS MUCH OF THE CWA THIS EVENING HAS ALLOWED
TEMPERATURES TO DROP QUICKLY. A COUPLE OF RURAL LOCATIONS HAVE HAD
WINDS DECOUPLE WITH CURRENT TEMPERATURES SITTING AT JUST BELOW 40
DEGREES. STILL THINK ONSHORE WINDS WILL START TO SLOW DOWN THE
SLIDE IN TEMPERATURES THIS EVENING WITH THE WESTERN ZONES AND
COASTAL COUNTIES HAVING TEMPERATURES STARTING TO LEVEL OFF BEFORE
SUNRISE. GFS AND ECMWF ARE TO FAST WITH THE MOISTURE RETURN WHILE
THE RAP IS MORE ON TARGET. GIVEN THIS HAVE LEANED TOWARDS THE RAP.
BECAUSE OF THE TRENDS ABOVE HAVE UPDATED MIN T GRIDS. REST OF
FORECAST LOOKS ON TRACK. 23
PREV DISCUSSION... /ISSUED 546 PM CST FRI JAN 3 2014/
DISCUSSION...
UPDATED AVIATION DISCUSSION.
AVIATION...
CLEAR SKY WITH SOUTHEAST WIND AT ALL TAF SITES AT THE MOMENT. AS
ONSHORE FLOW CONTINUES WILL SEE AN INCREASE IN CLOUDS VERY LATE
TONIGHT AND SATURDAY WITH OVERCAST CONDITIONS EXPECTED SATURDAY
AFTERNOON MOST SITES. SOME UNCERTAINTY IN RESULTING CEILINGS BUT
THINK WILL MOSTLY START OUT VFR WITH CLOUD BASE AROUND 4000 FEET
THEN LOWER INTO MVFR RANGE DURING THE AFTERNOON. CLOUDS OVER THE
GULF NOW ARE IN THAT 4000 FOOT RANGE LENDING SOME SUPPORT TO THIS
AND GFS MOS GENERALLY SUPPORTS THIS SCENARIO AS WELL. SOME OF THE
OTHER MODEL FIELDS WOULD SUGGEST MVFR CIGS PERHAPS ARRIVING A
LITTLE EARLIER SO WILL HAVE TO MONITOR.
ONLY EXCEPTION TO ALL THE ABOVE IS CLL WHERE DID BITE ON SOME
LOWER MVFR CIGS AROUND SUNRISE SATURDAY BASED ON MAJORITY OF
GUIDANCE. 46
PREV DISCUSSION... /ISSUED 331 PM CST FRI JAN 3 2014/
DISCUSSION...
A HIGHLY AMPLIFIED PATTERN ALOFT WILL LEAD TO A PUSH OF A VERY
COLD AIR MASS INTO SE TX EARLY NEXT WEEK. THIS WILL BE PRECEDED BY
A WARMUP TONIGHT AND SATURDAY AS ONSHORE WINDS HELP RETURN GULF
MOISTURE TO THE AREA. STRONG WARM AIR ADVECTION ON SATURDAY WILL
LEAD TO ABOVE NORMAL HIGH TEMPERATURES. THE MODELS ARE THEN
CONSISTENT IN PUSHING A COLD FRONT QUICKLY THROUGH THE AREA SUNDAY
MORNING. THE FRONT IS EXPECTED TO BE OFF THE COAST BEFORE NOON.
THE COLDEST AIR MASS OF THE SEASON IS THEN EXPECTED. MODEL
GUIDANCE STILL DIFFERS...HOWEVER THERE IS ENOUGH CONSENSUS TO SAY
WITH CONFIDENCE THAT MOST AREAS WILL EXPERIENCE AT LEAST FREEZING
OVERNIGHT LOW TEMPERATURES SUNDAY NIGHT AND MONDAY MORNING TOWARD
THE COAST...WITH LOCATIONS ALONG AND NORTH OF A LINE FROM LIBERTY
TO THE WOODLANDS TO COLUMBUS EXPERIENCING MID 20S. MONDAY NIGHT
AND EARLY TUESDAY MORNING WILL LIKELY BE THE COLDEST NIGHT AS THE
CENTER OF THE SURFACE HIGH PRESSURE RIDGE SETTLES OVER THE INLAND
COUNTIES. LOWER 20S LOOKS LIKELY ALONG AND NORTH OF A LINE FROM
LIBERTY TO THE WOODLANDS TO COLUMBUS. METRO HOUSTON MAY SEE
TEMPERATURES FALL INTO THE MID 20S AND UPPER 20S...WITH HARRIS
COUNTY LIKELY EXPERIENCING LOWER 20S IN THE NORTHWEST...MID 20S IN
THE CENTRAL...AND UPPER 20S TOWARD GALVESTON BAY. LOWS BETWEEN 28
AND 32 LOOK TO BE COMMON ALONG THE IMMEDIATE COAST.
WINDS BY TUESDAY AFTERNOON WILL BECOME ONSHORE AND A COMBINATION
OF WARM AIR ADVECTION AND MOISTURE ADVECTION WILL LEAD TO A
WARMING TREND PROBABLY THE END OF THE WORK WEEK.
40
AVIATION...
DID NOT MAKE ANY MAJOR CHANGES WITH THE 18Z TAFS. ONSHORE WINDS HAVE
RETURNED AREAWIDE WITH ONLY HIGH CLOUDS MENTIONED. OTHERWISE VFR. 41
MARINE...
ONSHORE WINDS WILL CONTINUE TO DEVELOP ACROSS THE COASTAL WATERS DUR-
ING THE OVERNIGHT HRS AS HIGH PRESSURE MOVES INTO THE E/NE U.S.. NOT
A LOT OF ISSUES FOR THE MARINE AREAS UNTIL SUN WITH THE ARRIVAL/PASS-
AGE OF THE NEXT COLD FRONT. THIS IS SYSTEM IS EXPECTED TO BRING VERY
STRONG/GUSTY NORTH WINDS TO THE AREA AND SMALL CRAFT ADVISORIES WILL
LIKELY BE REQUIRED BY SUN AFTN. 41
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 38 66 48 50 23 / 0 10 20 10 0
HOUSTON (IAH) 36 66 58 58 27 / 0 10 30 30 0
GALVESTON (GLS) 44 64 58 58 34 / 0 10 20 30 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NEW YORK NY
951 AM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE EAST THROUGH TONIGHT. LOW PRESSURE MOVING
FROM THE GULF COAST STATES ON SUNDAY INTO QUEBEC BY MONDAY WILL
THEN DRAG A POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC HIGH
PRESSURE WILL BUILDS IN LATER MONDAY THROUGH WEDNESDAY...THEN
SLIDE EAST WEDNESDAY NIGHT. A COLD FRONT WILL MOVE ACROSS ON
THURSDAY...FOLLOWED BY BUILDING HIGH PRESSURE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPS BEGINNING TO WARM...BUT WILL BE SLOW DUE TO THE FRESH
SNOWPACK AND UNUSUALLY COLD AIRMASS OVER THE REGION. TEMPS IN THE
LOCAL AREA HAVE RISEN TO ABOVE ZERO...AND SHOULD BE IN THE 20S BY
MIDDAY. WIND CHILLS IN THE SINGLE DIGITS TO JUST BELOW ZERO WILL
RISE INTO THE TEENS.
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH ASSOCIATED
SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER FAR EASTERN
ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS BEGINS TO BUILD
IN LATE IN THE AFTERNOON.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED
SW FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-FZDZ IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION FOR DETAILS ON
AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC. THERE IS ALSO A SMALL CHANCE
FOR WIND CHILLS AROUND -25 IN FAR NW ZONES - HAVE HIGHLIGHTED THIS
THREAT IN THE HWO.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -10 TO -20...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
VFR TODAY AS HIGH PRESSURE MOVES OFF THE MID ATLANTIC COAST.
SW SFC WINDS TODAY GENERALLY RIGHT DOWN 22 MAGNETIC. THERE COULD
BE AN ASOS REPORTED GUST TO UPPER TEENS AT JFK/EWR/LGA DURING THE
AFTN.
SOUTHERLY FLOW OVERNIGHT BRINGS MARGINAL CIGS UP THE EAST COAST
AND INTO THE LOCAL AREA BY MORNING. CHC FOR SOME FREEZING DRIZZLE
TO THE NYC METRO AND COASTAL TERMINALS IN THE PREDAWN HOURS ON
SUNDAY.
.OUTLOOK FOR 12Z SUNDAY THROUGH WED...
.SUN...MVFR. CHC FREEZING DRIZZLE EARLY...-RA AFTN. SE WND < 10
KT.
.SUN NGT-MON MORNING...IFR. RA. LLWS ALSO POSSIBLE WITH S-SW
WINDS INCREASING TO 40-45 KT AT FL015.
.MON AFTN-TUE...BECOMING VFR MON AFTN. W WND G25-35KT...HIGHEST
TUE AFTN.
.WED...VFR. W WINDS G20KT.
&&
.MARINE...
THERE IS SOME POTENTIAL ANZ-350 COULD HAVE A FEW HOURS LATE THIS
MORNING/EARLY THIS AFTERNOON WITH SEAS BELOW 5 FT THROUGHOUT THE
ZONE. HOWEVER...THIS LULL DOES NOT APPEAR IT WILL BE LONG ENOUGH
TO ADJUST THE EXISTING SCA ANY. STILL APPEAR ON TRACK FOR SEAS TO
BUILD BACK TO 5 FT BY LATE AFTERNOON IN ANZ-350.
INCREASING SW FLOW SHOULD BUILD OCEAN SEAS BACK TO 5 FT ON MOST
IF NOT ALL OCEAN WATERS TONIGHT. STEADY SE-S FLOW 15-20 KT SHOULD
THEN MAINTAIN SCA CONDS ON THE OCEAN ESPECIALLY OUT EAST INTO MON
MORNING.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 2
ISLIP...NY 10 2008 -1
LAGUARDIA...NY 4 1981 8
JFK AIRPORT...NY 8 1981 5
NYC-CENTRAL PARK...NY -3 1918 7
NEWARK...NJ 1 1981 3
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST MONDAY FOR ANZ350.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MALOIT/MPS
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...TONGUE
MARINE...GOODMAN/MALOIT
HYDROLOGY...MALOIT
CLIMATE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
924 AM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE EAST THROUGH TONIGHT. LOW PRESSURE MOVING
FROM THE GULF COAST STATES ON SUNDAY INTO QUEBEC BY MONDAY WILL
THEN DRAG A POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC HIGH
PRESSURE WILL BUILDS IN LATER MONDAY THROUGH WEDNESDAY...THEN
SLIDE EAST WEDNESDAY NIGHT. A COLD FRONT WILL MOVE ACROSS ON
THURSDAY...FOLLOWED BY BUILDING HIGH PRESSURE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPS BEGINNING TO WARM...BUT WILL BE SLOW DUE TO THE FRESH
SNOWPACK AND UNUSUALLY COLD AIRMASS OVER THE REGION. TEMPS IN THE
LOCAL AREA HAVE RISEN TO ABOVE ZERO...AND SHOULD BE IN THE 20S BY
MIDDAY. WIND CHILLS IN THE SINGLE DIGITS TO JUST BELOW ZERO WILL
RISE INTO THE TEENS.
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH ASSOCIATED
SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER FAR EASTERN
ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS BEGINS TO BUILD
IN LATE IN THE AFTERNOON.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED
SW FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-FZDZ IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION FOR DETAILS ON
AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC. THERE IS ALSO A SMALL CHANCE
FOR WIND CHILLS AROUND -25 IN FAR NW ZONES - HAVE HIGHLIGHTED THIS
THREAT IN THE HWO.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -10 TO -20...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE OVERHEAD THIS MORNING WILL SLIDE EAST THROUGH
TONIGHT.
HIGH CONFIDENCE VFR THROUGH THIS EVENING. LIGHT WINDS THIS
MORNING WILL BECOME SW 10 KT THIS AFTERNOON...THEN DIMINISH
SOMEWHAT AFTER DUSK.
A TEMPS COOL TONIGHT AND MOISTURE BEGINS TO INCREASE ON LIGHT SW
FLOW...CANNOT RULE OUT PATCHY MVFR VSBY AFTER MIDNIGHT. A WEAK
DISTURBANCE APPROACHING FROM THE SOUTH IS MORE LIKELY TO BRING
MVFR CIGS AND PATCHY FREEZING DRIZZLE TO THE NYC METRO AND COASTAL
TERMINALS IN THE PREDAWN HOURS ON SUNDAY.
.OUTLOOK FOR 12Z SUNDAY THROUGH WED...
.SUNDAY MORNING...MVFR CIGS LIKELY. PATCHY FOG AND/OR FREEZING
DRIZZLE POSSIBLE.
.SUNDAY AFTERNOON...MVFR OR LOWER CONDITIONS EXPECTED WITH
LIGHT RAIN.
.SUNDAY NIGHT-MON MORNING...IFR CONDITIONS LIKELY IN RAIN.
LLWS ALSO POSSIBLE WITH S-SW WINDS INCREASING TO 40-45 KT
AT FL015.
.MON AFTERNOON-TUE...CONDITIONS IMPROVING TO VFR. W WINDS
G25-30KT...THEN 30-35KT BY TUE AFTERNOON.
.WED...VFR. W WINDS G20KT.
&&
.MARINE...
THERE IS SOME POTENTIAL ANZ-350 COULD HAVE A FEW HOURS LATE THIS
MORNING/EARLY THIS AFTERNOON WITH SEAS BELOW 5 FT THROUGHOUT THE
ZONE. HOWEVER...THIS LULL DOES NOT APPEAR IT WILL BE LONG ENOUGH
TO ADJUST THE EXISTING SCA ANY. STILL APPEAR ON TRACK FOR SEAS TO
BUILD BACK TO 5 FT BY LATE AFTERNOON IN ANZ-350.
INCREASING SW FLOW SHOULD BUILD OCEAN SEAS BACK TO 5 FT ON MOST
IF NOT ALL OCEAN WATERS TONIGHT. STEADY SE-S FLOW 15-20 KT SHOULD
THEN MAINTAIN SCA CONDS ON THE OCEAN ESPECIALLY OUT EAST INTO MON
MORNING.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 2
ISLIP...NY 10 2008 -1
LAGUARDIA...NY 4 1981 8
JFK AIRPORT...NY 8 1981 5
NYC-CENTRAL PARK...NY -3 1918 7
NEWARK...NJ 1 1981 3
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST MONDAY FOR ANZ350.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MALOIT/MPS
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...GOODMAN
MARINE...GOODMAN/MALOIT
HYDROLOGY...MALOIT
CLIMATE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
655 AM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE EAST THROUGH TONIGHT. LOW PRESSURE MOVING
FROM THE GULF COAST STATES ON SUNDAY INTO QUEBEC BY MONDAY WILL
THEN DRAG A POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC HIGH
PRESSURE WILL BUILDS IN LATER MONDAY THROUGH WEDNESDAY...THEN
SLIDE EAST WEDNESDAY NIGHT. A COLD FRONT WILL MOVE ACROSS ON
THURSDAY...FOLLOWED BY BUILDING HIGH PRESSURE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MINOR CHANGES TO REFLECT THE LATEST TRENDS IN OBSERVATIONS AND
GUIDANCE. MAIN CHANGE WAS TO TWEAK TEMPERATURES OVER THE NEXT FEW
HOURS...MAINLY UPWARD A FEW DEGREES.
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH ASSOCIATED
SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER FAR EASTERN
ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS BEGINS TO BUILD
IN LATE IN THE AFTERNOON.
BRUTALLY COLD TO GET STARTED WITH INTERIOR ZONES AND PINE BARRENS
HAVING LOWS -10 TO -15...AND FROM 5 ABOVE TO -10 ELSEWHERE -
EXCEPT FROM 0 TO 10 ABOVE IN NYC. WILL CONTINUE WITH SPS
HIGHLIGHTING COLD TEMPERATURES EARLY. FORTUNATELY WINDS GENERALLY
LESS THAN 5 MPH - SO NO WIND CHILLS TO COMPOUND THINGS.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED SW
FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-FZDZ IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION FOR DETAILS ON
AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC. THERE IS ALSO A SMALL CHANCE
FOR WIND CHILLS AROUND -25 IN FAR NW ZONES - HAVE HIGHLIGHTED THIS
THREAT IN THE HWO.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -10 TO -20...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE OVERHEAD THIS MORNING WILL SLIDE EAST THROUGH
TONIGHT.
HIGH CONFIDENCE VFR THROUGH THIS EVENING. LIGHT WINDS THIS
MORNING WILL BECOME SW 10 KT THIS AFTERNOON...THEN DIMINISH
SOMEWHAT AFTER DUSK.
A TEMPS COOL TONIGHT AND MOISTURE BEGINS TO INCREASE ON LIGHT SW
FLOW...CANNOT RULE OUT PATCHY MVFR VSBY AFTER MIDNIGHT. A WEAK
DISTURBANCE APPROACHING FROM THE SOUTH IS MORE LIKELY TO BRING
MVFR CIGS AND PATCHY FREEZING DRIZZLE TO THE NYC METRO AND COASTAL
TERMINALS IN THE PREDAWN HOURS ON SUNDAY.
.OUTLOOK FOR 12Z SUNDAY THROUGH WED...
.SUNDAY MORNING...MVFR CIGS LIKELY. PATCHY FOG AND/OR FREEZING
DRIZZLE POSSIBLE.
.SUNDAY AFTERNOON...MVFR OR LOWER CONDITIONS EXPECTED WITH
LIGHT RAIN.
.SUNDAY NIGHT-MON MORNING...IFR CONDITIONS LIKELY IN RAIN.
LLWS ALSO POSSIBLE WITH S-SW WINDS INCREASING TO 40-45 KT
AT FL015.
.MON AFTERNOON-TUE...CONDITIONS IMPROVING TO VFR. W WINDS
G25-30KT...THEN 30-35KT BY TUE AFTERNOON.
.WED...VFR. W WINDS G20KT.
&&
.MARINE...
SCA ALLOWED TO EXPIRE FOR ANZ-355 AS SEAS AT 44017 AT 5.9 FT AND
WINDS CONTINUE TO DIMINISH. LEFT SCA FOR ANZ-353 AS IS FOR NOW -
THOUGH COULD END UP ENDING BEFORE SCHEDULED 9 AM END TIME.
ALSO...THERE IS SOME POTENTIAL ANZ-350 COULD HAVE A FEW HOURS
LATE THIS MORNING/EARLY THIS AFTERNOON WITH SEAS BELOW 5 FT
THROUGHOUT THE ZONE. HOWEVER...THIS LULL DOES NOT APPEAR IT WILL
BE LONG ENOUGH TO ADJUST THE EXISTING SCA ANY. STILL APPEAR ON
TRACK FOR SEAS TO BUILD BACK TO 5 FT BY LATE AFTERNOON IN ANZ-350.
INCREASING SW FLOW SHOULD BUILD OCEAN SEAS BACK TO 5 FT ON MOST
IF NOT ALL OCEAN WATERS TONIGHT. STEADY SE-S FLOW 15-20 KT SHOULD
THEN MAINTAIN SCA CONDS ON THE OCEAN ESPECIALLY OUT EAST INTO MON
MORNING.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 2
ISLIP...NY 10 2008 -1
LAGUARDIA...NY 4 1981 8
JFK AIRPORT...NY 8 1981 5
NYC-CENTRAL PARK...NY -3 1918 7
NEWARK...NJ 1 1981 3
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST MONDAY FOR ANZ350.
SMALL CRAFT ADVISORY UNTIL 9 AM EST THIS MORNING FOR ANZ353.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MALOIT
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...GOODMAN
MARINE...MALOIT/GOODMAN
HYDROLOGY...MALOIT
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
725 AM CST SAT JAN 4 2014
.UPDATE...
ISSUED AT 722 AM CST SAT JAN 4 2014
I HAVE SENT A FEW UPDATES TO CLOUD AND PRECIPITATION TRENDS. THE
LARGEST SIGNIFICANCE IS TO GREATLY INCREASE MORNING POPS ALONG AND
NORTH OF INTERSTATE 80. THE RAP MODEL CONTINUES TO SHOW
DEVELOPMENT OF A BAND OF ACCUMULATING SNOW NEAR THIS AXIS...AND
RECENT RADAR TRENDS SHOW ONE DEVELOPING THIS PAST HOUR. THIS WILL
BE CLOSELY WATCHED...AND AMOUNTS OF SNOW MAY NEED TO BE ADDED
EARLY TODAY ALONG AND JUST NORTH OF INTERSTATE 80.
ERVIN
&&
.SYNOPSIS...
ISSUED AT 236 AM CST SAT JAN 4 2014
THE LATEST SURFACE ANALYSIS SHOWS A COLD FRONT FROM THE MINNESOTA
ARROWHEAD SOUTHWEST THROUGH SOUTHEASTERN SOUTH DAKOTA INTO SOUTH
CENTRAL NEBRASKA. STRONG SOUTHERLY FLOW CONTINUED AHEAD OF THE
FRONT CAUSING SOME PATCHY BLOWING SNOW OVER THE MID MISSISSIPPI
VALLEY. PRECIPITATION WITH THE COLD FRONT WAS MAINLY FOCUSED OVER
NORTHEAST MINNESOTA AND NORTHERN WISCONSIN JUST AHEAD OF A WAVE
ALONG THE BOUNDARY. THE 00Z H8 ANALYSIS HAD THE 850 COLD FRONT FROM
THE EASTERN DAKOTAS INTO THE WESTERN NEBRASKA WITH A WEDGE OF WARM
AIR NOSING INTO NORTHERN SOUTH DAKOTA. THE COLDER AIR AS STILL
BOTTLED UP ALONG THE CANADIAN BORDER. AT 500MB A BROAD TROF WAS
LOCATED OVER THE NORTHERN ROCKIES WITH A CLOSED LOW OVER NORTHERN
ALBERTA. AN IMPRESSIVE AREA OF HEIGHT FALLS...LOCATED AHEAD OF THE
CLOSED LOW...EXTENDED FROM SASKATCHEWAN INTO THE CENTRAL ROCKIES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 236 AM CST SAT JAN 4 2014
THE SURFACE COLD FRONT WILL MOVE THROUGH THE CWFA THIS MORNING AND
EARLY THIS AFTERNOON. MODELS ARE CONSISTENT SHOWING THE
PRECIPITATION/SNOW OCCURRING BEHIND THE FRONT AND DEVELOPING AS THE
FRONT MOVES THROUGH THE REGION. THE LATEST PROGS SUGGEST THE SNOW
WILL BE DEVELOPING OVER THE NORTHWEST CWA THIS MORNING...AND THEN
BECOME MORE ORGANIZED/WIDESPREAD DURING THE LATE AFTERNOON AND
EVENING OVER THE SOUTHEASTERN HALF OF THE FORECAST AREA. KEPT
CHANCE POPS OVER THE NORTHWEST THIS MORNING. POPS WERE SHIFTED TO
THE SOUTHEAST AND INCREASED TO LIKELY/CATEGORICAL DURING THE
AFTERNOON AND OVERNIGHT. LOOKING AT FORCING WITH THE
BOUNDARY...MODEL PROGS SHOWN A PROLONGED PERIOD OF FGEN OVER THE
AREA THIS AFTERNOON INTO TONIGHT...BUT IT DOES NOT LOOK THAT
ORGANIZED. TIME SECTIONS ARE SIMILAR...DEPICTING A PROLONGED PERIOD
OF AT LEAST MID LEVEL WEAK LIFT. WITH THE FORCING LACKING GOOD
ORGANIZATION HAVE OPTED TO KEEP PRECIPITATION AMOUNTS IN LINE WITH
THE DRIER GFS/ECMWF PROGS WITH PRECIP AMOUNTS UP TO A QUARTER OF AN
INCH OVER THE SOUTHEAST HALF OF THE CWFA. USING SNOW TO LIQUID
RATIOS AROUND 16 TO 1 THAT YIELD UP TO 3 INCHES OF SNOW BY SUNDAY
MORNING OVER THE SOUTHEAST HALF WITH THE HIGHER AMOUNTS OVER THE FAR
SOUTHEAST CORNER. WITH THESE FORECAST SNOW AMOUNTS AND WINDS NOT
EXPECTED TO BE VERY STRONG...SIGNIFICANT BLOWING SNOW SHOULD NOT BE
A CONCERN. NO WINTER WX ADVISORY IS PLANNED AT THIS TIME FOR THIS
AFTERNOON OR TONIGHT.
AS FOR TEMPERATURES TODAY...HIGHS SHOULD BE REACHED EARLY WITH
SLOWLY FALLING TEMPERATURES DURING THE AFTERNOON. BY SUNDAY MORNING
READINGS WILL BE BACK IN THE SINGLE DIGITS WITH SUB ZERO TEMPS OVER
THE NORTHWEST. WIND CHILLS WILL BE APPROACHING -30 BY 6AM SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 236 AM CST SAT JAN 4 2014
THIS MORNINGS 20S WILL BE A DISTANT MEMORY SUNDAY MORNING...AS
INCREASINGLY STRONG ARCTIC COLD ADVECTION WILL BE WELL UNDERWAY. THE
MAIN CHALLENGE DURING THIS INITIAL PERIOD WILL BE ENDING ANY SNOW IN
THE EAST...AND TIMING ON THE ONSET OF WIND CHILL HEADLINES. THE
HEADLINES FOR WIND CHILL ARE THE HIGHEST CONCERN...AND KEEPING THE
MESSAGE CONSISTENT AND AS SIMPLE AS POSSIBLE HAS BEEN OUR GOAL ON
THIS ISSUANCE. PURE METEOROLOGICALLY...SUNDAY WILL BE MAINLY AN
ADVISORY DAY UNTIL LATE AFTERNOON...AS WILL TUESDAY MID
MORNING...HOWEVER...THIS IS JUST BRACKETS ON WHAT IS A HIGH
CONFIDENCE AND LIFE THREATENING WIND CHILL EVENT. A WARNING WILL BE
ISSUED FOR THE PRIOR WATCH COUNTIES IN THE NORTHWEST STARTING AT 6
AM SUNDAY MORNING...THEN THE REMAINDER OF COUNTIES WILL BEGIN AT
NOON SUNDAY. THIS ROUGHLY MATCHES THE WATCH...AND KEEP THE MESSAGE
CONSISTENT. BY FAR...THE WORST CONDITIONS WILL BE SUNDAY NIGHT
THROUGH MONDAY NIGHT...WITH A PROLONGED PERIOD OF -35 TO -45 CHILLS
AREA WIDE. THE NORTH HALF SHOULD MAX OUR WIND CHILL INTENSITY IN THE
-48 TO -53 BETWEEN 4 AM MONDAY AND 9 AM MONDAY. ACTUAL TEMPERATURES
WILL SLOWLY FALL SUNDAY WITHIN THE -5 TO +7 TEMPERATURE RANGE. BY
SUNDAY AT 6 PM...WE ARE ALREADY EXPECTING ACTUAL TEMPERATURES TO BY
-10 NORTHWEST TO -2 SOUTHEAST. LOWS SUNDAY NIGHT APPEAR SET THROUGH
PURE COLD ADVECTION/NO RADIATIONAL COOLING TO REACH -19 TO -25 IN
THE NORTH 1/2 TO -14 TO -19 IN THE SOUTH HALF. WINDS OVERNIGHT WILL
BE STRONG...SUSTAINED AROUND 20 TO 25 MPH...GUSTING TO 30 TO 35 MPH.
THIS IS WHY THE WIND CHILLS WILL BE SO EXCRUCIATINGLY COLD. SIMILAR
WINDS WILL CONTINUE THROUGH EARLY MONDAY EVENING...BEFORE SLOWLY
BACKING DOWN. IF ANYTHING...THIS MAY BE SLIGHTLY UNDERDONE GIVEN THE
WHOPPING GRADIENT BETWEEN A STRENGTHENING SUB 1000MB LOW IN THE
EASTERN GREAT LAKES...AND A ASTOUNDINGLY STRONG 1050+ MB HIGH
ENTERING MONTANA. THIS GRADIENT MAY CREATE LEGITIMATE BLOWING SNOW
THREAT SUNDAY AND SUNDAY NIGHT. IN ADDITION...INTENSE ADVECTION OF
ARCTIC AIR WILL KEEP THE BOUNDARY LAYER MIXED CONTINUOUSLY...WHICH
OFTEN IS UNDERPLAYED BY MODELS.
BEYOND TUESDAY...A WARM UP IS FORECAST...BUT IT WILL TAKE SEVERAL
DAYS TO RID THE REGION OF ARCTIC AIR. SOME OVER RUNNING SNOWS IS A
GROWING THREAT FOR WEDNESDAY AND THURSDAY...BUT AT THIS
POINT...MODELS DO NOT SHOW STRONG ENOUGH DYNAMICS TO CREATE MUCH OF
A STORM THREAT.
ERVIN
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 508 AM CST SAT JAN 4 2014
A VERY STRONG COLD FRONT WILL SWEEP THROUGH EASTERN IOWA AND
NORTHWEST ILLINOIS THIS MORNING...FOLLOWED BY A MUCH STRONGER
SURGE OF ARCTIC AIR SUNDAY. THE FRONT TODAY WILL SWITCH THE VFR
CONDITIONS AND SOUTHWEST WINDS OF 15 TO 25 KTS...TO WEST BY MID
MORNING. BY EARLY AFTERNOON...NORTHWEST WINDS OF 15 TO 25 KTS WILL
BECOME PREVALENT AT ALL SITES. LIGHT SNOW SHOULD DEVELOP JUST
BEHIND THE FRONT...AND BECOME WIDESPREAD FOR A TIME IN SOUTHEAST
IOWA AND ILLINOIS. MLI AND BRL WILL LIKELY SEE IFR VISIBILITIES IN
SNOW TOWARD VERY LATE AFTERNOON AND EARLY EVENING. THIS SNOW MAY
CONTINUE THROUGH MID MORNING SUNDAY BEFORE ENDING IN ILLINOIS. IT
IS UNLIKELY THAT MLI AND BRL WILL SEE SNOW CONTINUE BEYOND 12Z
SUNDAY. VERY VERY COLD AIR WILL BE FOUND THROUGH THE DAY SUNDAY.
STRONG NORTHWEST WINDS OF 20 TO 30 KTS WILL CONTINUE FROM LATER
TONIGHT THROUGH MONDAY NIGHT.
ERVIN
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WIND CHILL WARNING FROM 6 AM SUNDAY TO NOON CST TUESDAY FOR
BENTON-BUCHANAN-DELAWARE-DUBUQUE-JACKSON-JONES-LINN.
WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
CEDAR-CLINTON-DES MOINES-HENRY IA-IOWA-JEFFERSON-JOHNSON-
KEOKUK-LEE-LOUISA-MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...WIND CHILL WARNING FROM 6 AM SUNDAY TO NOON CST TUESDAY FOR JO
DAVIESS.
WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
BUREAU-CARROLL-HANCOCK-HENDERSON-HENRY IL-MCDONOUGH-MERCER-
PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
CLARK-SCOTLAND.
&&
$$
UPDATE...ERVIN
SYNOPSIS...DLF
SHORT TERM...DLF
LONG TERM...ERVIN
AVIATION...ERVIN
AREA FORECAST DISCUSSION
NWS TOPEKA KS
524 AM CST Sat Jan 4 2014
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 350 AM CST SAT JAN 4 2014
09Z water vapor imagery shows a broad upper level trough over much
of the country with one shortwave over the northern plains moving
towards MN and another shortwave digging southeast from ID towards
CO. At the surface a pre frontal trough has moved into north central
KS with the strong cold air advection lagging the wind shift by
about 125 miles.
For today and tonight, we should have good mid level frontogenesis
move across the forecast area. However the lack of a well organized
shortwave to provide good large scale forcing suggests snow amounts
will be relatively light. Additionally the better large scale
forcing is initially waisted on trying to saturate the column this
morning and into the early afternoon. There does appear to be some
conditional symmetric instability (CSI) just above the frontal
circulation which may be able to enhance snow rates. And with very
cold air moving in this evening, snow to water ratios are expected
to approach 20:1 overnight. So even with light QPF amounts, there is
the potential for 1 to 2 inches with locally higher amounts.
Ensemble mean progs generally support this idea of 1 to 2 inches. At
this point the area most likely to see the higher amounts looks to
be across east central KS since snowfall is expected to occur while
the ratios are highest. This would give areas along and southeast of
the KS turnpike around 2 inches by Sunday morning. With this in mind
and the potential for CSI to cause a local enhancement, will issue a
low end winter weather advisory beginning late this afternoon and
continuing into Sunday morning.
Because the cold air advection is lagging the front by a pretty
significant margin, have increased highs across east central KS into
the upper 30s with temps falling through the afternoon. Think the
cold air advection and increasing cloud cover will also cause temps
to fall across northern parts of the area this afternoon. Did not go
quite as cold for lows Sunday as MOS guidance would suggest since
north winds should keep the boundary layer mixed and skies remaining
mostly cloudy. So Lows are pretty similar to the previous forecast
with temps expected to fall between 5 and 10 degrees above zero.
Wolters
.LONG TERM...(Sunday through Friday)
Issued at 350 AM CST SAT JAN 4 2014
The upper shortwave trough continues to exit eastward on Sunday.
Lingering light snow is possible through the morning period mainly
for areas southeast of Interstate 35.
Attention quickly turns to the abnormally cold air as northerly
winds increase between 10 and 20 mph sustained Sunday afternoon.
Gusts near 25 mph combined with falling h85 temps well below zero
will result in wind chill readings near 0 to 8 below zero.
Conditions quickly worsen Sunday evening as temperatures descend
below zero. Gusts remain throughout the evening in upwards of 25-30
mph. The higher wind speeds will make it feel extremely cold as
wind chills from 25 to 30 below zero are expected throughout the
area. A Wind Chill Warning will likely be needed in the following
forecast shift. Despite the clearing skies on Monday afternoon, the
high temperatures struggle to the single digits as. Wind chills
remain hazardous through much of Monday from 0 to 13 below zero.
Surface high pressure gradually wanes the cold air advection,
weakening and shifting surface winds towards the west by early
Monday evening. Despite the lighter winds in place, the snow cover
and clear skies will drop low temps below zero, making it feel
anywhere from 10 to 18 below zero. In terms of precipitation
chances, a much weaker embedded wave within the northwest flow aloft
quickly enters north central Kansas Sunday afternoon and evening.
Moisture is greatly limited behind the previous system, making it
difficult for any developing ice crystals to reach the surface.
There is a brief period of mid level ascent seen especially from the
recent runs of the NAM and GFS where we could see a slight chance
for snow over north central areas through Sunday evening with a few
tenths at best. Flurries are possible elsewhere on Sunday evening
with no accumulations expected.
Southerly flow returns briefly Tuesday helping temps recover back
into the 20s and low 30s. Models are still bringing another mid
level trough northward from the Baja California Wednesday afternoon
and evening. Best ascent still remains far east of Kansas with
possible light precip developing on the back edge. Temperatures
hover near and just above the freezing mark Wednesday with the
chance of a rain and snow mix during the afternoon, switching to all
snow overnight. At this time, best chances for any light accumulating
snow would be across far east central areas. A temporary dry period
sets up through Friday as temps moderate closer to normal in the
30s.
&&
.AVIATION...(For the 12Z TAFs through 12Z Sunday Morning)
Issued at 523 AM CST SAT JAN 4 2014
06Z NAM and 10Z RAP have trended the band of snow developing
further north than either the GFS or ECMWF have. This reduces
confidence in whether the terminals will have IFR conditions. Also
have little confidence in models bringing MVFR CIGS in with the
front. OBS upstream show the MVFR CIGS are quite a ways removed
from the initial wind shift. Because of this have been rather
conservative with the TAFs, holding off on the MVFR conditions
until the snow is expected to move in. Could see some IFR VSBY
overnight with the snow and gusty north winds, but trying to
figure out the location of the heavier band and most likely
timing remains a low confidence exercise.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY from 3 PM this afternoon to 9 AM CST
Sunday FOR KSZ026-039-040-054>056-058-059.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1053 AM EST SAT JAN 4 2014
LATEST UPDATE...
UPDATE/MARINE
.SYNOPSIS...
ISSUED AT 330 AM EST SAT JAN 4 2014
A COLD FRONT WILL DROP DOWN INTO THE AREA TODAY AND SLOWLY MOVE
THROUGH THE AREA THROUGH THE DAY ON SUNDAY. SOME LIGHT SNOW WILL
DEVELOP ALONG THIS FRONT...AND WILL BECOME MORE WIDESPREAD THIS
EVENING AS IT PRESSES SOUTHEAST. ADDITIONAL SNOW WILL DEVELOP AND
MOVE ALONG THIS FRONT WITH A WAVE OF LOW PRESSURE ON SUNDAY AND
SUNDAY EVENING.
MUCH COLDER AIR WILL THEN OVERSPREAD THE AREA LATE SUNDAY AND INTO
MONDAY. TEMPERATURES WILL MAINLY FALL SUNDAY NIGHT AND MONDAY.
STRONG WINDS WILL COMBINE WITH THE COLD TO PRODUCE WIND CHILLS WELL
BELOW ZERO. THE AREA HAS NOT SEEN THE AIR THIS COLD AT LEAST FOR A
FEW YEARS. TEMPERATURES WILL MODERATE LATE NEXT WEEK.
&&
.UPDATE...
ISSUED AT 1051 AM EST SAT JAN 4 2014
I AM SERIOUSLY CONSIDERING EXPANDING THE WINTER STORM WARNING AT
LEAST ONE ROW OF COUNTIES FARTHER NORTH WITH THE AFTERNOON
FORECAST UPDATE. SEEMS TO ME THE MODEL CONSUS IS CONVERGING ON A
SOLUTION BETWEEN THE NAM AND THE GFS PUTTING THE HEAVIER
PRECIPITATION TONIGHT NEAR AND JUST SOUTH OF A LINE FROM NEAR
GRAND HAVEN TO GRAND RAPIDS TO ALMA. THE RAP 13Z AND NAM12 SHOW A
BAND OF .2 TO .4 QPF BY 12Z SUNDAY FROM ALONG THAT LINE...AS DOES
THE 12Z GFS. THIS SNOW BAND IS FGEN RELATED AND IS A REFLECTION
OF WHERE THE FRONT IS BETWEEN 850 AND 700 MB. WHICH TO ME
SUGGESTS HEAVY SNOW IS MORE THAN LIKELY ONE ROW OF COUNTIES
FATHER NORTH IN THE SHORT TERM. FOR NOW THOUGH I PLAN ON LEAVING
HEADLINES AS THEY ARE SINCE THE GFS IS STILL WELL SOUTH OF THE NAM
FOR SUNDAY AFTERNOON INTO SUNDAY NIGHT ON THE STORM QPF.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 330 AM EST SAT JAN 4 2014
WE WILL BE UPGRADING TO A WARNING FOR MOST OF THE AREA THAT WAS IN
THE WATCH. THE NW EDGE OF THE WATCH WILL BE TRANSITIONED TO AN
ADVISORY ALONG WITH SOME ADDITIONAL COUNTIES. THE MAIN PERIOD OF
CONCERN IN THE SHORT TERM IS FROM THIS EVENING INTO SUNDAY EVENING
WITH THE SNOW. THE WIND CHILL WATCH WILL BE MAINTAINED FOR THE TIME
BEING.
WE ARE EXPECTING SNOW TO BEGIN TO DEVELOP THIS MORNING ACROSS THE NW
CORNER OF THE CWFA. THE SNOW WILL START OUT RATHER LIGHT AS
THE AREA ALONG THE FRONT LIGHTS UP A BIT LIKELY AHEAD OF THE SHORT
WAVE THAT WILL APPROACH THE AREA FROM THE DAKOTAS. ALSO...THERE
LOOKS TO BE SOME LAKE ENHANCEMENT. DELTA T/S ARE NOT IN THE
TEENS...BUT THEY WILL BE ALMOST 10C WHICH IS USUALLY SUFFICIENT
ENOUGH FOR AT LEAST A SMALL BOOST FROM THE LAKE. THERE WILL ALSO BE
SOME ADDED CONVERGENCE FROM THE LAKE INFLUENCE THAT WILL ALSO HELP.
THE LIGHT SNOW WILL EXPAND A BIT THIS AFTERNOON AND THEN THIS
EVENING INTO THE CENTRAL PORTIONS OF THE AREA. THE AFOREMENTIONED
SHORT WAVE WILL INITIALLY ZIP TO THE NE OF THE CWFA AFTER 18Z TODAY.
WE WILL THEN SEE THE RRQ MOVE OVER THE AREA VIA A 140 KT JET STREAK
SOUTH OF JAMES BAY. THIS WILL ACT ON THE FRONT AND THE LIMITED LAKE
CONTRIBUTION TO SPREAD THE SNOW INLAND A BIT MORE. THE FRONT SHOULD
MOVE SE OF KGRR AFTER 00Z AND FOCUS THE BETTER SNOW DOWN THERE.
LIGHT SNOW WILL CONTINUE THEN ACROSS THE SE HALF OF THE CWFA LATER
TONIGHT AND EARLY SUN. WE LOSE THE UPPER JET DYNAMICS...BUT WE
CONTINUE WITH A GRADUAL ISENTROPIC ASCENT/OVERRUNNING SITUATION NW
OF THE FRONT THAT THEN STALLS OUT TO OUR SE. THIS FRONT WILL BE
AWAITING THE NEXT UPPER WAVE EXPECTED TO DIVE INTO THE SRN PLAINS
AROUND 12Z SUN BEFORE LIFTING NE TOWARD THE LOWER GREAT LAKES. THIS
WAVE WILL BRING ANOTHER ROUND OF SNOW ACROSS THE WARNING AREA SUN
AFTERNOON AND EVENING.
ONCE THE SYSTEM SNOW MOVES OUT SUN EVENING...WE WILL SEE NW FLOW
LAKE EFFECT BECOME ESTABLISHED WITH THE EXTREMELY COLD ARCTIC AIR
THAT WILL SPREAD ACROSS THE AREA.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 330 AM EST SAT JAN 4 2014
THE MAIN EMPHASIS IN THE LONG TERM CONTINUES TO BE ON THE BRUTALLY
COLD AIR MASS SWEEPING ACROSS MICHIGAN ON MONDAY AND TUESDAY. WIND
CHILLS ARE EXPECTED TO BE AROUND -25 OVER MOST OF THE AREA HOWEVER
VALUES ALONG THE I-94 CORRIDOR EAST OF KALAMAZOO MAY REACH AS LOW AS
-35 OR -40 MONDAY NIGHT WHERE A LK MI INFLUENCE PROBABLY WILL NOT BE
PRESENT AS SFC WINDS BECOME SOUTHWEST.
IN ADDITION TO THE SEVERE WIND CHILL READINGS... LAKE EFFECT SNOW
AND BLOWING SNOW WILL IMPACT THE AREA MONDAY AND TUESDAY.
ACCUMULATIONS WILL BE HELD DOWN DUE TO SMALL CRYSTAL SIZE BUT
VISIBILITIES SHOULD STILL BE GREATLY REDUCED AND ROADS WILL BE ICY
SINCE ROAD CHEMICALS WILL BE INEFFECTIVE WITH THE VERY COLD TEMPS.
THE REALLY COLD SFC AIR OF -10 TO -15 CURLING AROUND THE BOTTOM OF
LK MI INTO THE I-94 CORRIDOR REGION WILL LIKELY RESULT IN A NICE LOW
LEVEL CONVERGENCE/FGEN ZONE FOR THE LAKE EFFECT SNOW. A LENGTHY
EASTWARD/INLAND EXTENSION OF LAKE EFFECT SHOULD SET UP NEAR OR JUST
SOUTH OF THE I-96 CORRIDOR MONDAY NIGHT AND TUESDAY.
THE CORE OF THE COLDEST AIR LIFTS OUT TUESDAY NIGHT AND A MODERATING
TREND IN TEMPS IS EXPECTED FOR MID TO LATE WEEK. HIGHS BY FRIDAY
SHOULD BE UP NEAR 30. HOWEVER MORE LIGHT SNOW IS POSSIBLE WEDNESDAY
AND THURSDAY DUE TO WEAK WARM ADVECTION/ISENTROPIC LIFT PATTERN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 655 AM EST SAT JAN 4 2014
IFR CONDITIONS IN SNOW AND BLOWING SNOW ARE EXPECTED TO DEVELOP AT
MKG BY NOON THEN CONTINUE THIS AFTERNOON BEFORE LETTING UP SOME
TONIGHT. CONDITIONS AT MKG SHOULD THEN TRANSITION TO MVFR THIS
EVENING AND THE STRONG SOUTHWEST WINDS CURRENTLY GUSTING TO 40 KTS
WILL DIMINISH CONSIDERABLY BY THAT TIME AS WELL.
GRR SHOULD ALSO SEE IFR CONDITIONS IN SNOW DEVELOPING THIS
AFTERNOON...THEN CONTINUING TONIGHT.
SOUTH AND EAST OF GRR... SNOW SHOULD HOLD OFF UNTIL AFTER 00Z
TONIGHT WITH IFR SNOW DEVELOPING AFTER 06Z AT AZO/BTL/LAN/JXN.
MUCH OF TODAY WILL ACTUALLY REMAIN VFR SOUTH AND EAST OF GRR WITH
SOUTHWEST WINDS GUSTING TO 30 KTS. WINDS EVERYWHERE WILL DIMINISH
TO LESS THAN 10 KTS TONIGHT.
&&
.MARINE...
ISSUED AT 1051 AM EST SAT JAN 4 2014
I HAVE DOWNGRADED THE GALE WARNING TO A SMALL CRAFT ADVISORY SINCE
WINDS ARE DIMINISHING AS I WRITE THIS. WE MAY NEED A GALE WARNING
AND FREEZING SPRAY WARNING SUNDAY NIGHT INTO MONDAY BUT WILL NOT
ISSUE THAT JUST YET.
&&
.HYDROLOGY...
ISSUED AT 315 PM EST FRI JAN 3 2014
A FLOOD ADVISORY IS IN EFFECT FOR THE FLAT RIVER AT SMYRNA. A
SUSPECTED ICE JAM UPSTREAM HAS CAUSED A SHARP RISE FOLLOWED BY A
SHARP DECLINE AT THE SMYRNA RIVER GAUGE. ICE JAMS CAN CAUSE RAPID
FLUCTUATIONS IN RIVER LEVELS.
RIVERS WILL CONTINUE GAINING ICE COVERAGE AND THICKNESS FOR THE
FORESEEABLE FUTURE. THOSE RIVERS THAT ICE OVER COMPLETELY WILL HAVE
A MINIMAL ICE JAM THREAT. RIVERS WITH JAGGED ICE BUILDUP ARE IN
DANGER OF EXPERIENCING JAMMING AND RAPID FLUCTUATIONS. 6 OR MORE
INCHES OF SNOW IS EXPECTED FOR SOUTHERN AND SOUTHEAST LOWER MICHIGAN
SATURDAY NIGHT THROUGH SUNDAY EVENING. A BLAST OF EXTREME COLD AIR
FOLLOWS THE SNOW ON SUNDAY NIGHT.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 1 AM EST
MONDAY FOR MIZ051-052-056>058-064.
WIND CHILL WATCH FROM LATE SUNDAY NIGHT THROUGH TUESDAY
AFTERNOON FOR MIZ037>040-043>046-050>052-056>059-064>067-
071>074.
WINTER STORM WARNING FROM 7 PM THIS EVENING TO 1 AM EST MONDAY
FOR MIZ059-065>067-071>074.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
LMZ844>849.
&&
$$
UPDATE...WDM
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...MEADE
AVIATION...MEADE
HYDROLOGY...EBW
MARINE...WDM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
710 AM EST SAT JAN 4 2014
.UPDATE...
ISSUED AT 709 AM EST SAT JAN 4 2014
EXTENDED GOING WINTER STORM WARNING FOR ALGER COUNTY THRU 15Z WITH
SGNFT RADAR ECHOES LINGERING OVER THAT AREA UNDER THE DPVA/H85-5
QVECTOR CNVGC AHEAD OF SHRTWV MOVING E INTO THE UPR LKS. LARGER
SCALE SUBSIDENCE/MID LVL DRYING IN THE WAKE OF THIS DISTURBANCE WL
CAUSE THE SN TO DIMINISH IN ALGER COUNTY BY LATE MRNG.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EST SAT JAN 4 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW VIGOROUS SHRTWV
SHIFTING E FM MN INTO THE UPR GRT LKS. THIS DISTURBANCE IS REFLECTED
BY A SFC LO PRES TROF IN MN...WHILE ANOTHER WEAKER DISTURBANCE/LO
PRES IS SHIFTING THRU ONTARIO. ALTHOUGH THERE IS NO WELL DEFINED SFC
LO PRES CENTER...THE SHARP PRES GRADIENT BTWN THE GENERAL LO PRES
TROF TO THE W AND RETREATING SFC HI PRES OVER THE MID ATLANTIC
STATES IS SUPPORTING A VERY STRONG SW FLOW INTO THE UPR LKS...WITH
THE 00Z GRB RAOB SHOWING AN IMPRESSIVE SW WIND UP TO 70 KTS AT H85.
THE ISENTROPIC ASCENT ASSOCIATED WITH THIS STRONG SW FLOW SUPPORTED
A BAND OF HEAVIER SN THAT IMPACTED MAINLY THE NRN PORTION OF UPR MI
AS WELL AS AREAS DOWNWIND OF LK MI...WHERE THE FLOW OFF THE WATER
IN THE PRESENCE OF THE RETREATING ARCTIC AIRMASS ALLOWED FOR SGNFT
LK ENHANCEMENT/SN FALL RATES UP TO AN INCH PER HR. THE LLVL
DESTABILIZATION ALSO SHARPENED LLVL LAPSE RATES AND ALLOWED FOR SFC
WIND GUSTS NEAR THE BAY OF GREEN BAY/LK MI TO REACH AS HI AS 68 MPH
AT A SITE NEAR THOMPSON IN SCHOOLCRAFT COUNTY. THE AREA OF STRONGEST
LLVL WINDS/SHARPER ISENTROPIC ASCENT/SUPPORTING CENTER OF VIGOROUS
H85-5 QVECTOR CNVGC IS TENDING TO DRIFT E EARLY THIS MRNG...SO THE
SW WINDS/SN INTENSITY ARE DIMINSING A BIT. BUT ANOTHER AREA OF SN TO
THE W ASSOCIATED WITH THE DPVA/ACCOMPANYING DEEP LYR QVECTOR CNVGC
ACCOMPANYING THE MN SHRTWV IS TENDING TO PUSH BACK INTO THE AREA.
LOOKING FARTHER TO THE W...COLDER AIR IS PLOWING BACK INTO THE NRN
PLAINS BEHIND A COLD FNT SWEEPING THRU MN. AN EVEN COLDER ARCTIC
AIRMASS ASSOCIATED WITH ANOTHER SHRTWV DIGGING SEWD THRU
ALBERTA/SASKATCHEWAN IS APRCHG THE NRN PLAINS.
MAIN FCST CONCERNS IN THE SHORT TERM ARE POPS ASSOCIATED WITH APRCHG
MN SHRTWV AND THEN TEMPS/LES AS THE MUCH COLDER AIR UPSTREAM IN THE
WAKE OF THIS DISTURBANCE SURGES INTO THE UPR LKS.
TODAY...AREA OF DPVA/DEEP LYR QVECTOR CNVGC SUPPORTING THE AREA OF
WDSPREAD SN MOVING INTO THE WRN CWA EARLY THIS MRNG IS PROGGED TO
MOVE OUT OF THE ERN CWA BTWN 15Z-18Z...SO TRENDED SYNOPTIC SCALE
POPS DOWN W-E IN LINE WITH GOING FCST WITH ARRIVAL OF DNVA/CAD/DEEP
LYR QVECTOR DVGC AND STRONG SUBSIDENCE/MID LVL DRYING IN THE WAKE OF
MN SHRTWV PASSAGE. BUT OVER THE W...LES WL DVLP IN THE COLD NW FLOW
BEHIND THE FROPA AS H85 TEMPS FALL TOWARD -18C BY 00Z SUN.
HOWEVER...FCST SUBSIDENCE IS PROGGED TO DROP THE INVRN BASE TO AS LO
AS 3-4K FT. NAM/GFS/LOCAL WRF ARW FCST SNGS ALSO INDICATE GENERAL
SUBSIDENCE IN THE MIXED LYR BLO THE INVRN...SO LES AMOUNTS SHOULD BE
RELATIVELY LGT. HI RES MODELS INDICATE THE MORE FOCUSED LLVL CNVGC
WL IMPACT NRN ONTONAGON/SRN HOUGHTON COUNTY. ALTHOUGH TEMPS WL RISE
INTO THE 20S THIS MRNG BEFORE SFC COLD FNT NOW IN MN CLEARS THE CWA
W-E AND NEWBERRY IN THE AFTN...TEMPS WL FALL W-E FOLLOWING THE FROPA
WITH THE ARRIVAL OF THE COLDER H85 TEMPS.
TNGT...COLDER AIR ASSOCIATED WITH DIGGING SHRTWV IN WRN CANADA/
DEEPENING ARCTIC BRANCH IN THE PLAINS IS PROGGED TO STEADILY ADVECT
INTO THE UPR GRT LKS IN STEADY WNW FLOW/H925 WINDS 20-25KTS.
CONSENSUS OF FAVORED MODELS INDICATES H85 TEMPS WL FALL TO ARND -25C
OVER THE WRN CWA AND -18C OVER THE E BY 12Z SUN. ALTHOUGH THIS CHILL
WITH H85/LK WATER TEMP DIFFERENCE OVER 20C WL SUPPORT LES... HIER
RES MODELS ARE INDICATING LO INVRN BASE MAINTAINED BY ONGOING
SUBIDENCE THAT EXTENDS INTO THE MIXED LYR WL HAMPER LES AMOUNTS. SO
A RELATIVELY HI POP/LO QPF SCENARIO SEEMS TO BE IN STORE. THE
ARRIVING CHILL WL ALSO PUSH THE DGZ BLO THE SFC OVER THE WRN CWA...
SO THIS POOR SN GROWTH WL ALSO HAMPER LES AMOUNTS. BUT THE SMALL SN
FLAKE SIZE WL BE EFFICIENT AT REDUCING VSBY...ESPECIALLY AT EXPOSED
LOCATIONS NEAR LK SUP. EXPECT TEMPS OVER THE INTERIOR W HALF...WHERE
THE INCOMING AIRMASS WL BE MODIFIED LEAST BY THE WARMING OF LK
SUP...TO FALL AS LO AS 15 TO 20 BLO ZERO. WITH APRNT TEMPS LIKELY TO
FALL TO -25 TO -35...OPTED TO ISSUE A WIND CHILL ADVY FOR LATE TNGT
THRU SUN MRNG FOR THE INTERIOR W HALF COUNTIES EVEN THOUGH WIND
SPEEDS MAY NOT HOLD AOA THE THRESHOLD OF 10 MPH.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 505 AM EST SAT JAN 4 2014
...WIND CHILL WATCH ISSUED FOR SUNDAY NIGHT THROUGH LATE TUESDAY
MORNING...
A CLOSED 500MB LOW WILL SETTLE OVER THE GREAT LAKES SUNDAY INTO
MONDAY NIGHT...AND THEN MOVE INTO ONTARIO AND QUEBEC TUESDAY INTO
WEDNESDAY. UPPER MICHIGAN WILL REMAIN UNDER RATHER ZONAL FLOW ALOFT
FROM TUESDAY INTO WEDNESDAY AS THE LOW DEPARTS...AND THEN ANOTHER
TROUGH WILL SWING THROUGH AGAIN ON THURSDAY AS A RIDGE BUILDS OVER
THE NORTHERN PLAINS. AT THE SURFACE...THE LOW RESPONSIBLE FOR THE
EARLY WEEKEND SNOW OVER UPPER MI WILL MOVE INTO JAMES BAY SUNDAY
MORNING. THIS WILL ALLOW A VERY COLD ARCTIC AIRMASS OVER THE
CANADIAN PRAIRIE TO SINK INTO THE MIDWEST FOR SUNDAY AND MONDAY.
MEANWHILE...LOW PRESSURE DEVELOPING IN THE CENTRAL PLAINS SUNDAY
AFTERNOON WILL MOVE NORTHEASTWARD INTO THE LOWER LAKES BY MONDAY
MORNING...AND INTO ONTARIO BY MONDAY EVENING. THIS WILL ALLOW THE
ARCTIC AIRMASS TO FULLY INFILTRATE UPPER MICHIGAN SUNDAY NIGHT INTO
WEDNESDAY...BRINGING SOME OF THE COLDEST TEMPERATURES OF THE SEASON.
MODELS ARE CONSISTENT IN HAVING 850MB TEMPS RANGING FROM -28C TO
-35C CREEPING INTO THE WESTERN CWA STARTING LATE SUNDAY
AFTERNOON...AND THEN SLIDING OVER THE REST OF THE CWA THROUGH
TUESDAY. OVERALL...EXPECT SUNDAY NIGHT LOW TEMPERATURES TO RANGE
FROM -29F TO AROUND -3F ACROSS THE FORECAST AREA...WITH THE COLDEST
TEMPERATURES FAR WEST NEAR THE WI BORDER. HIGH TEMPERATURES ON
MONDAY WILL ONLY REBOUND TO NEAR -13F OUT WEST...AND INTO THE SINGLE
DIGITS ABOVE ZERO IN THE EAST. TEMPERATURES MONDAY NIGHT WILL RANGE
FROM -27F OUT WEST...AND -14C OUT EAST. AREAS NEAR THE LAKESHORE
WILL BE IN THE SINGLE DIGITS BELOW ZERO. AS PREVIOUS STATEMENTS AND
DISCUSSIONS HAVE MENTIONED...THIS IS THE COLDEST AIR MASS SINCE
PERHAPS THE INTENSE COLD WAVE OF EARLY FEBRUARY 1996.
TO WORSEN MATTERS...THE TIGHT PRESSURE GRADIENT BETWEEN THE INCOMING
HIGH AND THE LOW PRESSURE MOVING OVER THE LOWER LAKES WILL KEEP
WEST-NORTHWEST WINDS GUSTING OVER THE CWA THROUGH SUNDAY NIGHT
THROUGH TUESDAY NIGHT...WHICH WILL LEAD TO DANGEROUSLY COLD WIND
CHILLS...EVEN DURING THE DAY. AREAS ACROSS THE INLAND WEST WILL SEE
WIND CHILL VALUES AS LOW AS -50F DURING THE OVERNIGHT
HOURS...WHEREAS THE REMAINDER OF THE AREA WILL SEE VALUES RANGING
FROM -40F TO -20F. HAVE ISSUED A WIND CHILL WATCH FOR SUNDAY NIGHT
INTO MONDAY MORNING ACROSS THE WEST ACCORDINGLY...WHERE WIND CHILL
VALUES ARE EXPECTED TO REMAIN CRITICAL THROUGH A MAJORITY OF THE
PERIOD. DELAYED THE WATCH FOR THE EASTERN HALF UNTIL MONDAY
NIGHT...AS VALUES ARE NOT EXPECTED TO STEADILY REACH WIND CHILL
WARNING CRITERIA UNTIL THEN. SEE THE LATEST WINTER WEATHER MESSAGE
FOR ADDITIONAL DETAILS AND PRECAUTIONARY MEASURES.
AS FAR AS PRECIPITATION SUNDAY INTO TUESDAY GOES...WITH VERY COLD
TEMPERATURES AND WEST-NORTHWEST WINDS THROUGH THE TIME PERIOD/AN
UPPER LEVEL LOW ALOFT/ EXPECT LES TO DEVELOP AND PERSIST IN FAVORED
SNOWBELTS ACROSS MICHIGAN. THE LIMITING FACTOR...AS WE HAVE SEEN IN
THE PAST FEW WEEKS WITH COLDER TEMPS...WILL BE THE SNOW RATIOS AS
THE DGZ PLUMMETS INTO THE GROUND. OVERALL...THINKING THE 15-17:1
RATIOS ARE REASONABLE AS LAST WEEKS SNOW TOTALS DURING THE COLDER
TEMPS WERE IN THIS RANGE. WHILE SNOW TOTALS ARE NOT EXPECTED TO BE
TOO IMPRESSIVE...GUSTY WINDS WILL LEAD TO AREAS OF BLOWING
SNOW...ESPECIALLY MONDAY INTO TUESDAY. TOTALS IN WNW-FAVORED
SNOWBELTS ALONG LAKE SUPERIOR ARE EXPECTED TO BE AROUND 1 TO 3
INCHES THROUGH MONDAY MORNING...AND THEN 2 TO 5 INCHES MONDAY
MORNING INTO TUESDAY MORNING...WITH THE HIGHEST ACCUMULATIONS
EXPECTED EAST OF MUNISING. ADVISORIES MAY BE NEEDED IN AREAS WITH
THE MOST ACCUMULATIONS/MOST BLOWING SNOW LATER THIS WEEK...SO STAY
TUNED FOR THE LATEST.
OTHERWISE...HIGH PRESSURE KEEPS THINGS FAIRLY QUIET FOR WEDNESDAY
INTO THURSDAY...AND KEEPS WINDS LIGHTER. LOW PRESSURE WILL MOVE FROM
NORTHERN MANITOBA THURSDAY INTO JAMES BAY BY SATURDAY...WHICH WILL
BRING SOUTH-SOUTHWESTERLY FLOW ACROSS UPPER MICHIGAN ALONG WITH
WARMER AIR...THANKFULLY. HIGH TEMPERATURES WILL REBOUND INTO THE
TEENS AND 20S STARTING THURSDAY...AND REMAINING LES FOR
WEST-NORTHWEST WIND FAVORED SNOWBELTS WILL MOVE OFFSHORE INTO LAKE
SUPERIOR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 709 AM EST SAT JAN 4 2014
CMX...EXPECT IFR CONDITIONS TO PREVAIL THIS FCST PERIOD WITH LGT SN
IN ADVANCE OF AN APRCHG COLD FNT GIVING WAY TO LK EFFECT SHSN/BLSN
FOLLOWING THE FROPA THIS MRNG. ALTHOUGH STRONG SUBSIDENCE AND SOME
DRIER AIR WL FOLLOW THE FROPA...UPSLOPE GUSTY W WIND WITH ARRIVAL OF
MUCH COLDER AIR WL SUPPORT PERSISTENT LK EFFECT -SHSN/BLSN OF SMALL
FLAKES THAT ARE EFFICIENT AT REDUCING VSBY AND IFR CONDITIONS THRU
THE ENTIRE FCST PERIOD.
IWD...ALTHOUGH SOME SN/IFR VSBYS MAY IMPACT THIS SITE THIS MRNG
COINCIDENT WITH A COLD FROPA...EXPECT MVFR CONDITIONS TO PREDOMINATE
WITH SOME LK EFFECT -SHSN FOLLOWING THE FROPA.
SAW...EXPECT MVFR CONDITIONS WITH SOME -SN IN ADVANCE OF A COLD FNT
THIS MRNG. THERE SHOULD BE ENUF DRYING/SUBSIDENCE TO CAUSE
CONDITIONS TO IMPROVE TO VFR LATER TDAY/TNG IN THE PRESENCE OF A
DOWNSLOPE WNW FLOW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 505 AM EST SAT JAN 4 2014
SW GALES AHEAD OF AN APPROACHING COLD FRONT OVER EASTERN LAKE
SUPERIOR WILL DIMINISH THIS MORNING WITH THE ARRIVAL OF A WEAKER
PRES GRADIENT. IT NOW APPEARS THE NW WINDS BEHIND THE FRONT WL NOT
BE AS STRONG AS EARLIER ANTICIPATED AND NOT REACH GALE THRESHOLDS
EXCEPT PERHAPS OVER THE E PART OF THE LAKE THIS AFTERNOON. SO OPTED
TO CANX THE GOING GALE WARNING FOR ALL BUT THAT AREA. DID SHORTERN
THE WARNING FOR THE E THIS EVENING SINCE THE MARGINAL GALES THERE
WILL DIMINISH BY THEN. EVEN THOUGH THE NW WINDS WILL BE UP TO ONLY
25-30 KTS INSTEAD OF 35 KTS THRU TONIGHT...THE ARRIVAL OF BITTERLY
COLD ARCTIC AIR/SUFFICIENTLY HI WAVES WILL RESULT IN WIDESPREAD
HEAVY FREEZING SPRAY...ESPECIALLY THIS AFTERNOON AND TONIGHT.
WEST TO NORTHWEST WINDS OF 15 TO 25 KNOTS WILL CONTINUE FROM SUNDAY
INTO MONDAY MORNING. THE TIGHTENING PRESSURE GRADIENT BETWEEN LOW
PRESSURE OVER THE NEW ENGLAND STATES AND INCOMING HIGH PRESSURE FROM
THE NORTHERN PLAINS WILL BRING NORTHWEST GALES TO 40 KNOTS TO MAINLY
CENTRAL AND EASTERN LAKE SUPERIOR MONDAY AFTERNOON INTO TUESDAY
EVENING. HIGH PRESSURE WILL RETURN WEDNESDAY INTO THURSDAY AND BRING
WINDS DOWN BELOW 20 KNOTS. APPROACHING LOW PRESSURE WILL BRING
SOUTHERLY WINDS 15 TO 25 KNOTS TO LAKE SUPERIOR FOR FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WATCH FROM SUNDAY EVENING THROUGH TUESDAY MORNING FOR
MIZ001>005-009>013-084.
WIND CHILL ADVISORY FROM MIDNIGHT EST /11 PM CST/ TONIGHT TO
NOON EST /11 AM CST/ SUNDAY FOR MIZ002-004-005-009>013-084.
WINTER STORM WARNING UNTIL NOON EST TODAY FOR MIZ007-014-085.
WIND CHILL WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR
MIZ006-007-014-085.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR MIZ001-
003.
WINTER STORM WARNING UNTIL 10 AM EST THIS MORNING FOR MIZ006.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ266-267.
HEAVY FREEZING SPRAY WARNING UNTIL 4 AM EST /3 AM CST/ TUESDAY
FOR LSZ162-263>266.
HEAVY FREEZING SPRAY WARNING FROM 1 PM THIS AFTERNOON TO 7 AM
EST MONDAY FOR LSZ249>251.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST MONDAY FOR
LSZ243>245-248.
LAKE MICHIGAN...
HEAVY FREEZING SPRAY WARNING UNTIL 10 AM EST THIS MORNING FOR
LMZ248-250.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LMZ221-248-250.
&&
$$
UPDATE...KC
SHORT TERM...KC
LONG TERM...MCD
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
511 AM EST SAT JAN 4 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EST SAT JAN 4 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW VIGOROUS SHRTWV
SHIFTING E FM MN INTO THE UPR GRT LKS. THIS DISTURBANCE IS REFLECTED
BY A SFC LO PRES TROF IN MN...WHILE ANOTHER WEAKER DISTURBANCE/LO
PRES IS SHIFTING THRU ONTARIO. ALTHOUGH THERE IS NO WELL DEFINED SFC
LO PRES CENTER...THE SHARP PRES GRADIENT BTWN THE GENERAL LO PRES
TROF TO THE W AND RETREATING SFC HI PRES OVER THE MID ATLANTIC
STATES IS SUPPORTING A VERY STRONG SW FLOW INTO THE UPR LKS...WITH
THE 00Z GRB RAOB SHOWING AN IMPRESSIVE SW WIND UP TO 70 KTS AT H85.
THE ISENTROPIC ASCENT ASSOCIATED WITH THIS STRONG SW FLOW SUPPORTED
A BAND OF HEAVIER SN THAT IMPACTED MAINLY THE NRN PORTION OF UPR MI
AS WELL AS AREAS DOWNWIND OF LK MI...WHERE THE FLOW OFF THE WATER
IN THE PRESENCE OF THE RETREATING ARCTIC AIRMASS ALLOWED FOR SGNFT
LK ENHANCEMENT/SN FALL RATES UP TO AN INCH PER HR. THE LLVL
DESTABILIZATION ALSO SHARPENED LLVL LAPSE RATES AND ALLOWED FOR SFC
WIND GUSTS NEAR THE BAY OF GREEN BAY/LK MI TO REACH AS HI AS 68 MPH
AT A SITE NEAR THOMPSON IN SCHOOLCRAFT COUNTY. THE AREA OF STRONGEST
LLVL WINDS/SHARPER ISENTROPIC ASCENT/SUPPORTING CENTER OF VIGOROUS
H85-5 QVECTOR CNVGC IS TENDING TO DRIFT E EARLY THIS MRNG...SO THE
SW WINDS/SN INTENSITY ARE DIMINSING A BIT. BUT ANOTHER AREA OF SN TO
THE W ASSOCIATED WITH THE DPVA/ACCOMPANYING DEEP LYR QVECTOR CNVGC
ACCOMPANYING THE MN SHRTWV IS TENDING TO PUSH BACK INTO THE AREA.
LOOKING FARTHER TO THE W...COLDER AIR IS PLOWING BACK INTO THE NRN
PLAINS BEHIND A COLD FNT SWEEPING THRU MN. AN EVEN COLDER ARCTIC
AIRMASS ASSOCIATED WITH ANOTHER SHRTWV DIGGING SEWD THRU
ALBERTA/SASKATCHEWAN IS APRCHG THE NRN PLAINS.
MAIN FCST CONCERNS IN THE SHORT TERM ARE POPS ASSOCIATED WITH APRCHG
MN SHRTWV AND THEN TEMPS/LES AS THE MUCH COLDER AIR UPSTREAM IN THE
WAKE OF THIS DISTURBANCE SURGES INTO THE UPR LKS.
TODAY...AREA OF DPVA/DEEP LYR QVECTOR CNVGC SUPPORTING THE AREA OF
WDSPREAD SN MOVING INTO THE WRN CWA EARLY THIS MRNG IS PROGGED TO
MOVE OUT OF THE ERN CWA BTWN 15Z-18Z...SO TRENDED SYNOPTIC SCALE
POPS DOWN W-E IN LINE WITH GOING FCST WITH ARRIVAL OF DNVA/CAD/DEEP
LYR QVECTOR DVGC AND STRONG SUBSIDENCE/MID LVL DRYING IN THE WAKE OF
MN SHRTWV PASSAGE. BUT OVER THE W...LES WL DVLP IN THE COLD NW FLOW
BEHIND THE FROPA AS H85 TEMPS FALL TOWARD -18C BY 00Z SUN.
HOWEVER...FCST SUBSIDENCE IS PROGGED TO DROP THE INVRN BASE TO AS LO
AS 3-4K FT. NAM/GFS/LOCAL WRF ARW FCST SNGS ALSO INDICATE GENERAL
SUBSIDENCE IN THE MIXED LYR BLO THE INVRN...SO LES AMOUNTS SHOULD BE
RELATIVELY LGT. HI RES MODELS INDICATE THE MORE FOCUSED LLVL CNVGC
WL IMPACT NRN ONTONAGON/SRN HOUGHTON COUNTY. ALTHOUGH TEMPS WL RISE
INTO THE 20S THIS MRNG BEFORE SFC COLD FNT NOW IN MN CLEARS THE CWA
W-E AND NEWBERRY IN THE AFTN...TEMPS WL FALL W-E FOLLOWING THE FROPA
WITH THE ARRIVAL OF THE COLDER H85 TEMPS.
TNGT...COLDER AIR ASSOCIATED WITH DIGGING SHRTWV IN WRN CANADA/
DEEPENING ARCTIC BRANCH IN THE PLAINS IS PROGGED TO STEADILY ADVECT
INTO THE UPR GRT LKS IN STEADY WNW FLOW/H925 WINDS 20-25KTS.
CONSENSUS OF FAVORED MODELS INDICATES H85 TEMPS WL FALL TO ARND -25C
OVER THE WRN CWA AND -18C OVER THE E BY 12Z SUN. ALTHOUGH THIS CHILL
WITH H85/LK WATER TEMP DIFFERENCE OVER 20C WL SUPPORT LES... HIER
RES MODELS ARE INDICATING LO INVRN BASE MAINTAINED BY ONGOING
SUBIDENCE THAT EXTENDS INTO THE MIXED LYR WL HAMPER LES AMOUNTS. SO
A RELATIVELY HI POP/LO QPF SCENARIO SEEMS TO BE IN STORE. THE
ARRIVING CHILL WL ALSO PUSH THE DGZ BLO THE SFC OVER THE WRN CWA...
SO THIS POOR SN GROWTH WL ALSO HAMPER LES AMOUNTS. BUT THE SMALL SN
FLAKE SIZE WL BE EFFICIENT AT REDUCING VSBY...ESPECIALLY AT EXPOSED
LOCATIONS NEAR LK SUP. EXPECT TEMPS OVER THE INTERIOR W HALF...WHERE
THE INCOMING AIRMASS WL BE MODIFIED LEAST BY THE WARMING OF LK
SUP...TO FALL AS LO AS 15 TO 20 BLO ZERO. WITH APRNT TEMPS LIKELY TO
FALL TO -25 TO -35...OPTED TO ISSUE A WIND CHILL ADVY FOR LATE TNGT
THRU SUN MRNG FOR THE INTERIOR W HALF COUNTIES EVEN THOUGH WIND
SPEEDS MAY NOT HOLD AOA THE THRESHOLD OF 10 MPH.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 505 AM EST SAT JAN 4 2014
...WIND CHILL WATCH ISSUED FOR SUNDAY NIGHT THROUGH LATE TUESDAY
MORNING...
A CLOSED 500MB LOW WILL SETTLE OVER THE GREAT LAKES SUNDAY INTO
MONDAY NIGHT...AND THEN MOVE INTO ONTARIO AND QUEBEC TUESDAY INTO
WEDNESDAY. UPPER MICHIGAN WILL REMAIN UNDER RATHER ZONAL FLOW ALOFT
FROM TUESDAY INTO WEDNESDAY AS THE LOW DEPARTS...AND THEN ANOTHER
TROUGH WILL SWING THROUGH AGAIN ON THURSDAY AS A RIDGE BUILDS OVER
THE NORTHERN PLAINS. AT THE SURFACE...THE LOW RESPONSIBLE FOR THE
EARLY WEEKEND SNOW OVER UPPER MI WILL MOVE INTO JAMES BAY SUNDAY
MORNING. THIS WILL ALLOW A VERY COLD ARCTIC AIRMASS OVER THE
CANADIAN PRAIRIE TO SINK INTO THE MIDWEST FOR SUNDAY AND MONDAY.
MEANWHILE...LOW PRESSURE DEVELOPING IN THE CENTRAL PLAINS SUNDAY
AFTERNOON WILL MOVE NORTHEASTWARD INTO THE LOWER LAKES BY MONDAY
MORNING...AND INTO ONTARIO BY MONDAY EVENING. THIS WILL ALLOW THE
ARCTIC AIRMASS TO FULLY INFILTRATE UPPER MICHIGAN SUNDAY NIGHT INTO
WEDNESDAY...BRINGING SOME OF THE COLDEST TEMPERATURES OF THE SEASON.
MODELS ARE CONSISTENT IN HAVING 850MB TEMPS RANGING FROM -28C TO
-35C CREEPING INTO THE WESTERN CWA STARTING LATE SUNDAY
AFTERNOON...AND THEN SLIDING OVER THE REST OF THE CWA THROUGH
TUESDAY. OVERALL...EXPECT SUNDAY NIGHT LOW TEMPERATURES TO RANGE
FROM -29F TO AROUND -3F ACROSS THE FORECAST AREA...WITH THE COLDEST
TEMPERATURES FAR WEST NEAR THE WI BORDER. HIGH TEMPERATURES ON
MONDAY WILL ONLY REBOUND TO NEAR -13F OUT WEST...AND INTO THE SINGLE
DIGITS ABOVE ZERO IN THE EAST. TEMPERATURES MONDAY NIGHT WILL RANGE
FROM -27F OUT WEST...AND -14C OUT EAST. AREAS NEAR THE LAKESHORE
WILL BE IN THE SINGLE DIGITS BELOW ZERO. AS PREVIOUS STATEMENTS AND
DISCUSSIONS HAVE MENTIONED...THIS IS THE COLDEST AIR MASS SINCE
PERHAPS THE INTENSE COLD WAVE OF EARLY FEBRUARY 1996.
TO WORSEN MATTERS...THE TIGHT PRESSURE GRADIENT BETWEEN THE INCOMING
HIGH AND THE LOW PRESSURE MOVING OVER THE LOWER LAKES WILL KEEP
WEST-NORTHWEST WINDS GUSTING OVER THE CWA THROUGH SUNDAY NIGHT
THROUGH TUESDAY NIGHT...WHICH WILL LEAD TO DANGEROUSLY COLD WIND
CHILLS...EVEN DURING THE DAY. AREAS ACROSS THE INLAND WEST WILL SEE
WIND CHILL VALUES AS LOW AS -50F DURING THE OVERNIGHT
HOURS...WHEREAS THE REMAINDER OF THE AREA WILL SEE VALUES RANGING
FROM -40F TO -20F. HAVE ISSUED A WIND CHILL WATCH FOR SUNDAY NIGHT
INTO MONDAY MORNING ACROSS THE WEST ACCORDINGLY...WHERE WIND CHILL
VALUES ARE EXPECTED TO REMAIN CRITICAL THROUGH A MAJORITY OF THE
PERIOD. DELAYED THE WATCH FOR THE EASTERN HALF UNTIL MONDAY
NIGHT...AS VALUES ARE NOT EXPECTED TO STEADILY REACH WIND CHILL
WARNING CRITERIA UNTIL THEN. SEE THE LATEST WINTER WEATHER MESSAGE
FOR ADDITIONAL DETAILS AND PRECAUTIONARY MEASURES.
AS FAR AS PRECIPITATION SUNDAY INTO TUESDAY GOES...WITH VERY COLD
TEMPERATURES AND WEST-NORTHWEST WINDS THROUGH THE TIME PERIOD/AN
UPPER LEVEL LOW ALOFT/ EXPECT LES TO DEVELOP AND PERSIST IN FAVORED
SNOWBELTS ACROSS MICHIGAN. THE LIMITING FACTOR...AS WE HAVE SEEN IN
THE PAST FEW WEEKS WITH COLDER TEMPS...WILL BE THE SNOW RATIOS AS
THE DGZ PLUMMETS INTO THE GROUND. OVERALL...THINKING THE 15-17:1
RATIOS ARE REASONABLE AS LAST WEEKS SNOW TOTALS DURING THE COLDER
TEMPS WERE IN THIS RANGE. WHILE SNOW TOTALS ARE NOT EXPECTED TO BE
TOO IMPRESSIVE...GUSTY WINDS WILL LEAD TO AREAS OF BLOWING
SNOW...ESPECIALLY MONDAY INTO TUESDAY. TOTALS IN WNW-FAVORED
SNOWBELTS ALONG LAKE SUPERIOR ARE EXPECTED TO BE AROUND 1 TO 3
INCHES THROUGH MONDAY MORNING...AND THEN 2 TO 5 INCHES MONDAY
MORNING INTO TUESDAY MORNING...WITH THE HIGHEST ACCUMULATIONS
EXPECTED EAST OF MUNISING. ADVISORIES MAY BE NEEDED IN AREAS WITH
THE MOST ACCUMULATIONS/MOST BLOWING SNOW LATER THIS WEEK...SO STAY
TUNED FOR THE LATEST.
OTHERWISE...HIGH PRESSURE KEEPS THINGS FAIRLY QUIET FOR WEDNESDAY
INTO THURSDAY...AND KEEPS WINDS LIGHTER. LOW PRESSURE WILL MOVE FROM
NORTHERN MANITOBA THURSDAY INTO JAMES BAY BY SATURDAY...WHICH WILL
BRING SOUTH-SOUTHWESTERLY FLOW ACROSS UPPER MICHIGAN ALONG WITH
WARMER AIR...THANKFULLY. HIGH TEMPERATURES WILL REBOUND INTO THE
TEENS AND 20S STARTING THURSDAY...AND REMAINING LES FOR
WEST-NORTHWEST WIND FAVORED SNOWBELTS WILL MOVE OFFSHORE INTO LAKE
SUPERIOR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1247 AM EST SAT JAN 4 2014
CMX...EXPECT IFR CONDITIONS TO PREVAIL THIS FCST PERIOD WITH LGT SN
IN ADVANCE OF AN APRCHG COLD FNT. ALTHOUGH SOME DRIER AIR WL FOLLOW
THE FROPA THIS MRNG...UPSLOPE GUSTY W WIND WITH ARRIVAL OF MUCH
COLDER AIR WL SUPPORT PERSISTENT LK EFFECT -SHSN/BLSN AND THE IFR
CONDITIONS.
IWD...ALTHOUGH SOME SN/LOWER IFR VSBYS WL IMPACT THIS SITE THIS MRNG
COINCIDENT WITH A COLD FROPA...EXPECT PREDOMINANT MVFR CONDITIONS TO
PREDOMINATE WITH SOME LK EFFECT -SHSN FOLLOWING THE FROPA.
SAW...EXPECT INTERMITTENT IFR CONDITIONS EARLY IN THE FCST PERIOD
WITH SN/BLSN TO GIVE WAY TO MVFR CONDITIONS WITH SOME DRYING ALF.
FOLLOWING A COLD FROPA LATER THIS MRNG...THE ARRIVAL OF DRIER AIR
WITH A DOWNSLOPE WNW FLOW WL CAUSE CONDITIONS TO IMPROVE TO VFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 505 AM EST SAT JAN 4 2014
SW GALES AHEAD OF AN APPROACHING COLD FRONT OVER EASTERN LAKE
SUPERIOR WILL DIMINISH THIS MORNING WITH THE ARRIVAL OF A WEAKER
PRES GRADIENT. IT NOW APPEARS THE NW WINDS BEHIND THE FRONT WL NOT
BE AS STRONG AS EARLIER ANTICIPATED AND NOT REACH GALE THRESHOLDS
EXCEPT PERHAPS OVER THE E PART OF THE LAKE THIS AFTERNOON. SO OPTED
TO CANX THE GOING GALE WARNING FOR ALL BUT THAT AREA. DID SHORTERN
THE WARNING FOR THE E THIS EVENING SINCE THE MARGINAL GALES THERE
WILL DIMINISH BY THEN. EVEN THOUGH THE NW WINDS WILL BE UP TO ONLY
25-30 KTS INSTEAD OF 35 KTS THRU TONIGHT...THE ARRIVAL OF BITTERLY
COLD ARCTIC AIR/SUFFICIENTLY HI WAVES WILL RESULT IN WIDESPREAD
HEAVY FREEZING SPRAY...ESPECIALLY THIS AFTERNOON AND TONIGHT.
WEST TO NORTHWEST WINDS OF 15 TO 25 KNOTS WILL CONTINUE FROM SUNDAY
INTO MONDAY MORNING. THE TIGHTENING PRESSURE GRADIENT BETWEEN LOW
PRESSURE OVER THE NEW ENGLAND STATES AND INCOMING HIGH PRESSURE FROM
THE NORTHERN PLAINS WILL BRING NORTHWEST GALES TO 40 KNOTS TO MAINLY
CENTRAL AND EASTERN LAKE SUPERIOR MONDAY AFTERNOON INTO TUESDAY
EVENING. HIGH PRESSURE WILL RETURN WEDNESDAY INTO THURSDAY AND BRING
WINDS DOWN BELOW 20 KNOTS. APPROACHING LOW PRESSURE WILL BRING
SOUTHERLY WINDS 15 TO 25 KNOTS TO LAKE SUPERIOR FOR FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WATCH FROM SUNDAY EVENING THROUGH TUESDAY MORNING FOR
MIZ001>005-009>013-084.
WIND CHILL ADVISORY FROM MIDNIGHT EST /11 PM CST/ TONIGHT TO
NOON EST /11 AM CST/ SUNDAY FOR MIZ002-004-005-009>013-084.
WINTER STORM WARNING UNTIL NOON EST TODAY FOR MIZ007-014-085.
WIND CHILL WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR
MIZ006-007-014-085.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR MIZ001-
003.
WINTER STORM WARNING UNTIL 7 AM EST THIS MORNING FOR MIZ006.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ266-267.
HEAVY FREEZING SPRAY WARNING UNTIL 4 AM EST /3 AM CST/ TUESDAY
FOR LSZ162-263>266.
HEAVY FREEZING SPRAY WARNING FROM 1 PM THIS AFTERNOON TO 7 AM
EST MONDAY FOR LSZ249>251.
HEAVY FREEZING SPRAY WARNING FROM 10 AM THIS MORNING TO 7 AM EST
MONDAY FOR LSZ243>245-248.
LAKE MICHIGAN...
HEAVY FREEZING SPRAY WARNING UNTIL 10 AM EST THIS MORNING FOR
LMZ248-250.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LMZ221-248-250.
&&
$$
SHORT TERM...KC
LONG TERM...MCD
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1141 AM MST SAT JAN 4 2014
.UPDATE...
ISSUED AT 1139 AM MST SAT JAN 4 2014
WILL ISSUE A SNOW ADVISORY FOR ALL OF THE PIKES PEAK REGION. 2-4"
OF SNOW HAS BEEN REPORTED AND AN ADDITIONAL 2-4" WILL BE POSSIBLE
GIVEN TRENDS IN SAT PIX DATA AND HRRR GUIDANCE. SNOW OVER THE
PIKES PEAK REGION SHOULD DECREASE AROUND SUNSET.
UPDATE ISSUED AT 737 AM MST SAT JAN 4 2014
MADE SOME MINOR ADJUSTMENTS TO POPS AND SNOW AMOUNTS...AND UPDATED
MORNING TEMPS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 339 AM MST SAT JAN 4 2014
AN UPR TROF WL CONTINUE MOVING SOUTHEAST OVR THE AREA TODAY AND WL
MOVE OUT OF THE AREA BY LATE TONIGHT. THIS SYSTEM WL BRING MUCH
COLDER TEMPS TO THE AREA TODAY AND TONIGHT. A COLD FRONT ASSOCIATED
WITH THIS SYSTEM WL BE MOVING THRU SERN CO THIS MORNING...BRINGING
SOME GUSTY N TO NE WINDS. THE LATEST MODEL RUNS END UP WITH A MORE
EASTERLY...THAN NORTHERLY COMPONENT TO THE SFC WINDS BY LATER THIS
MORNING AND INTO THE AFTERNOON...PROVIDING A LITTLE BETTER
UPSLOPE...AT LEAST IN THE LOW LEVELS. THE MID LEVEL FLOW WL BE N TO
NW THIS AFTERNOON AND EVENING. LOW LEVEL MSTR WL BE INCREASING
BEHIND THE FRONT WITH LOW CLOUDS FORMING AND SNOW SPREADING
SOUTHWARD. THE CENTRAL MTS WL CONTINUE TO SEE SNOW THRU THE DAY.
THE CURRENT SNOW ADVISORY FOR THAT AREA STILL LOOKS GOOD. AS FOR
SNOW AMOUNTS OVR THE ERN MTS AND PLAINS...THE GFS AND NAM HAVE SOME
DIFFERENCES ALONG THE ARKANSAS RIVER VALLEY...WITH THE GFS BEING
HEAVIER WITH THE SNOW AMOUNTS. FOR THE REST OF THE AREA...THE GFS
IS ALSO A LITTLE HIGHER THAN THE NAM...BUT HAS THE SAME GENERAL
IDEA...WITH HIGHER AMOUNTS OVR THE PIKES PEAK...TELLER COUNTY AND
NRN EL PASO COUNTY AREAS AND ALONG THE SRN BORDER AREAS AND SERN
FOOTHILLS. WL GO WITH AMOUNTS THAT ARE GENERALLY IN BETWEEN THE NAM
AND GFS. IT LOOKS LIKE PIKE PEAK COULD SEE AMOUNTS THAT MEET
ADVISORY CRITERIA SO WL ISSUE THAT FROM LATE THIS MORNING INTO THE
EARLY EVENING HOURS.
TONIGHT...AS THE UPR TROF EXITS THE AREA TO THE SOUTH AND
EAST...PCPN CHANCES WL DECREASE OR END...EXCEPT THAT THE SRN BORDER
AREA AND SERN FOOTHILLS WL CONTINUE TO SEE SOME LIGHT SNOW INTO THE
LATE NIGHT HOURS. SOME LIGHT SNOW WL ALSO LIKELY CONTINUE OVR
PORTIONS OF THE CENTRAL CO MTS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 339 AM MST SAT JAN 4 2014
SUNDAY...LONGWAVE TROUGH WILL BE SITUATED OVER THE MIDSECTION OF THE
COUNTRY SUNDAY MORNING...WHILE ACROSS THE CWA THE BRUNT OF SNOW
SHOULD BE ON THE WANE. ANOTHER LOBE OF ENERGY WILL ROTATE SOUTH
ACROSS THE STATE...BRINGING ANOTHER COLD FRONT DOWN ACROSS THE
PALMER DVD AND E PLAINS BY MIDDAY. THIS FRONT WILL HELP TO PRODUCE A
FEW ADDITIONAL SNOW SHOWERS FOR THE HIGHER TERRAIN AND PORTIONS OF
THE PLAINS THROUGH SUNDAY EVE...BUT SIGNIFICANT NEW ACCUMULATIONS
ARE NOT EXPECTED. TEMPS WILL STAY COLD HOWEVER...WITH THE ENTIRE
FORECAST AREA NOT EXPECTED TO BREAK 30 DEGREES.
MONDAY AND TUESDAY...SHORTWAVE RIDGING WILL SWEEP ACROSS THE STATE
ON MON BEFORE TRANSITIONING TO A MORE WESTERLY FLOW ALOFT. LATEST
NUMERICAL GUIDANCE INDICATES A SLIGHTLY WARMER SOLUTION FOR MON...SO
MAX TEMPS ON MON HAVE BEEN BOOSTED SLIGHTLY AND IF THE TREND
CONTINUES WILL HAVE TO BE WARMED EVEN FURTHER IN LATER FORECAST
PACKAGES. TEMPS ON TUE SHOULD WARM NICELY WITH THE INCREASING
WESTERLY FLOW...WITH MAX TEMPS PUSHING 50 F. ONGOING GRIDS HAVE DRY
CONDITIONS ON MON...WITH ISOLATED SNOW RETURNING TO THE CENTRAL MTS
TUE AFTN AND EVE...BUT LATEST MODEL SOLUTIONS NOW INDICATE DRY
CONDITIONS TO PERSIST A LITTLE LONGER...SO THIS PCPN THREAT WILL
MOST LIKELY BE DELAYED IN A LATER ISSUANCE.
WEDNESDAY THROUGH FRIDAY...GFS AND EC MODELS BOTH INDICATE AN
UNSETTLED PATTERN APPROACHING FOR THE LATTER HALF OF THE WORK
WEEK...WITH MULTIPLE UPPER DISTURBANCES CROSSING THE ROCKY MT
REGION. THE EXTENDED PROCEDURE OUTPUT OF MAX TEMPS IN THE MID 40S
FOR THE PLAINS...20S AND 30S FOR THE HIGH VALLEYS...AND A DAILY
ISOLATED THREAT OF SNOW FOR THE HIGHER TERRAIN LOOKS REASONABLE AT
THIS TIME. BOTH THE GFS AND EC HAVE BEEN WAVERING ON PLACEMENT AND
STRENGTH OF AN UPPER LOW IN THE THU/FRI TIME FRAME...SO CONFIDENCE
IN THE LONG RANGE IS LOW AT THIS TIME. MOORE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1005 AM MST SAT JAN 4 2014
FOR KCOS...SNOW WILL CONTINUE THROUGH LATE AFTERNOON. EXPECT 1 TO
3 INCHES AT THE AIRPORT. SNOW WILL END BY EARLY EVENING WITH VFR
CONDITIONS BY LATE EVENING.
FOR KPUB...SNOW SHOWERS WILL CONTINUE INTO EARLY EVENING. MAY SEE
UP TO AN INCH OF SNOW. SKIES WILL CLEAR BY LATE EVENING.
FOR KALS...VFR THROUGH PERIOD. MAY SEE SOME SNOW SHOWERS LATER
THIS AFTERNOON AND EARLY EVENING WITH BRIEF MVFR.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 PM MST THIS EVENING FOR COZ081-
084-085.
WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR COZ058-060.
WINTER WEATHER ADVISORY UNTIL 8 PM MST THIS EVENING FOR COZ082.
&&
$$
UPDATE...HODANISH
SHORT TERM...28
LONG TERM...MOORE
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1247 PM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE EAST THROUGH TONIGHT. LOW PRESSURE MOVING
FROM THE GULF COAST STATES ON SUNDAY INTO QUEBEC BY MONDAY WILL
THEN DRAG A POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC HIGH
PRESSURE WILL BUILDS IN LATER MONDAY THROUGH WEDNESDAY...THEN
SLIDE EAST WEDNESDAY NIGHT. A COLD FRONT WILL MOVE ACROSS ON
THURSDAY...FOLLOWED BY BUILDING HIGH PRESSURE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPS UP INTO THE UPPER TEENS ACROSS THE INTERIOR TO MID/UPPER 20S
ELSEWHERE. AS A RESULT...WIND CHILLS ARE CLIMBING INTO THE TEENS.
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH
ASSOCIATED SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER
FAR EASTERN ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS
BEGINS TO BUILD IN LATE IN THE AFTERNOON.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED
SW FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-FZDZ IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION FOR DETAILS ON
AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC. THERE IS ALSO A SMALL CHANCE
FOR WIND CHILLS AROUND -25 IN FAR NW ZONES - HAVE HIGHLIGHTED THIS
THREAT IN THE HWO.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -10 TO -20...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR THROUGH THIS EVENING AS HIGH PRESSURE MOVES OFF THE MID
ATLANTIC COAST.
SW SFC WINDS TODAY GENERALLY RIGHT DOWN 22 MAGNETIC. THERE COULD
BE AN ASOS REPORTED GUST TO UPPER TEENS AT JFK/EWR/LGA DURING THIS AFTN.
SW FLOW ALOFT OVERNIGHT BRINGS MARGINAL CIGS UP THE EAST COAST
AND INTO THE LOCAL AREA TOWARDS MORNING. INCLUDED VERY LIGHT FZDZ
FOR THE NYC METRO AND COASTAL TERMINALS IN THE EARLY MORNING...BUT
ONLY GIVE THIS A 50% CHC OF OCCURRENCE ATTM.
.OUTLOOK FOR 18Z SUNDAY THROUGH THU...
.SUN AFTN...MVFR > IFR. -RA. SE WND < 10 KT.
.SUN NGT-MON MORNING...IFR. RA BR.
.MON AFTN-TUE...BECOMING VFR MON AFTN. W WND G25-35KT...HIGHEST
TUE AFTN.
.WED...VFR. W WINDS G20KT.
.THU...VFR. CHC MVFR -SN LATE.
&&
.MARINE...
ANZ350 DOWN BELOW SCA CONDS...BUT MAY BE CLOSE FROM TIME TO TIME
INTO THE AFTERNOON.
CONDS MAY BRIEFLY BUILD TO SCA CONDS FOR A FEW HOURS THIS
EVENING...BUT WILL NOT CARRY HEADLINES ATTM.
INCREASING SOUTHERLY FLOW ON SUNDAY WILL RESULT IN WIDESPREAD SCA
CONDS ON THE OCEAN WATERS SUNDAY NIGHT THROUGH MONDAY. SCA LIKELY
ON MONDAY FOR THE REST OF THE WATERS.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 2
ISLIP...NY 10 2008 -1
LAGUARDIA...NY 4 1981 8
JFK AIRPORT...NY 8 1981 5
NYC-CENTRAL PARK...NY -3 1918 7
NEWARK...NJ 1 1981 3
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM SUNDAY TO 6 PM EST MONDAY FOR
ANZ350-353-355.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MPS
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...TONGUE
MARINE...GOODMAN/MALOIT
HYDROLOGY...MALOIT
CLIMATE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1223 PM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE EAST THROUGH TONIGHT. LOW PRESSURE MOVING
FROM THE GULF COAST STATES ON SUNDAY INTO QUEBEC BY MONDAY WILL
THEN DRAG A POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC HIGH
PRESSURE WILL BUILDS IN LATER MONDAY THROUGH WEDNESDAY...THEN
SLIDE EAST WEDNESDAY NIGHT. A COLD FRONT WILL MOVE ACROSS ON
THURSDAY...FOLLOWED BY BUILDING HIGH PRESSURE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPS UP INTO THE UPPER TEENS ACROSS THE INTERIOR TO MID/UPPER 20S
ELSEWHERE. AS A RESULT...WIND CHILLS ARE CLIMBING INTO THE TEENS.
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH
ASSOCIATED SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER
FAR EASTERN ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS
BEGINS TO BUILD IN LATE IN THE AFTERNOON.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED
SW FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-FZDZ IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION FOR DETAILS ON
AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC. THERE IS ALSO A SMALL CHANCE
FOR WIND CHILLS AROUND -25 IN FAR NW ZONES - HAVE HIGHLIGHTED THIS
THREAT IN THE HWO.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -10 TO -20...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /17Z SATURDAY THROUGH WEDNESDAY/...
VFR TODAY AS HIGH PRESSURE MOVES OFF THE MID ATLANTIC COAST.
SW SFC WINDS TODAY GENERALLY RIGHT DOWN 22 MAGNETIC. THERE COULD
BE AN ASOS REPORTED GUST TO UPPER TEENS AT JFK/EWR/LGA DURING THE
AFTN.
SOUTHERLY FLOW OVERNIGHT BRINGS MARGINAL CIGS UP THE EAST COAST
AND INTO THE LOCAL AREA BY MORNING. CHC FOR SOME FREEZING DRIZZLE
TO THE NYC METRO AND COASTAL TERMINALS IN THE PREDAWN HOURS ON
SUNDAY.
.OUTLOOK FOR 12Z SUNDAY THROUGH WED...
.SUN...MVFR. CHC FREEZING DRIZZLE EARLY...-RA AFTN. SE WND < 10
KT.
.SUN NGT-MON MORNING...IFR. RA. LLWS ALSO POSSIBLE WITH S-SW
WINDS INCREASING TO 40-45 KT AT FL015.
.MON AFTN-TUE...BECOMING VFR MON AFTN. W WND G25-35KT...HIGHEST
TUE AFTN.
.WED...VFR. W WINDS G20KT.
&&
.MARINE...
ANZ350 DOWN BELOW SCA CONDS...BUT MAY BE CLOSE FROM TIME TO TIME
INTO THE AFTERNOON.
CONDS MAY BRIEFLY BUILD TO SCA CONDS FOR A FEW HOURS THIS
EVENING...BUT WILL NOT CARRY HEADLINES ATTM.
INCREASING SOUTHERLY FLOW ON SUNDAY WILL RESULT IN WIDESPREAD SCA
CONDS ON THE OCEAN WATERS SUNDAY NIGHT THROUGH MONDAY. SCA LIKELY
ON MONDAY FOR THE REST OF THE WATERS.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 2
ISLIP...NY 10 2008 -1
LAGUARDIA...NY 4 1981 8
JFK AIRPORT...NY 8 1981 5
NYC-CENTRAL PARK...NY -3 1918 7
NEWARK...NJ 1 1981 3
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM SUNDAY TO 6 PM EST MONDAY FOR
ANZ350-353-355.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MALOIT/MPS
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...TONGUE
MARINE...GOODMAN/MALOIT
HYDROLOGY...MALOIT
CLIMATE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
101 PM CST SAT JAN 4 2014
.UPDATE...
ISSUED AT 1255 PM CST SAT JAN 4 2014
HAVE ISSUED A WINTER WEATHER ADVISORY FOR TONIGHT AND SUNDAY FOR
EXTREME NORTHEAST MO...EXTREME SE IA AND WESTERN IL. STORM SYSTEM
WILL BE TRACKING FROM THE SOUTHERN PLAINS INTO OHIO AND IT APPEARS
THAT 2 TO 5 INCHES WILL OCCUR IN OUR SE CWA. COMBINE THIS WITH
WIND GUSTS OVER 30 MPH AND THERE SHOULD BE CONSIDERABLE BLOWING
AND DRIFTING. THERE IS A POSSIBILITY LATER SHIFTS MAY NEED TO GO
WITH A WINTER STORM WARNING IF THE TRACK OF THE STORM IS FARTHER NORTH.
UPDATE ISSUED AT 1155 AM CST SAT JAN 4 2014
ARCTIC FRONT LATE THIS MORNING EXTENDED FROM JUST WEST OF DUBUQUE
TO IOWA CITY AND THEN TO KANSAS CITY. AHEAD OF THE FRONT
TEMPERATURES HAVE PUSHED INTO THE LOWER TO MID 30S BUT BEHIND THE
FRONT READINGS HAD FALLEN TO 12 ABOVE IN NW IA BUT WERE BELOW ZERO
FROM ND TO NORTHERN MN. THE FRONT WILL CONTINUE TO PUSH EASTWARD
ACROSS THE CWA AS THE AFTERNOON PROGRESSES WITH FALLING TEMPERATURES.
BAND OF LIGHT SNOW HAS DEVELOPED AHEAD OF THE FRONT IN EASTERN IA
AND NW IL AND HAVE RAISED POPS TO LIKELY WITH ACCUMULATIONS OF
LESS THAN AN INCH THIS AFTERNOON.
UPDATE ISSUED AT 722 AM CST SAT JAN 4 2014
I HAVE SENT A FEW UPDATES TO CLOUD AND PRECIPITATION TRENDS. THE
LARGEST SIGNIFICANCE IS TO GREATLY INCREASE MORNING POPS ALONG AND
NORTH OF INTERSTATE 80. THE RAP MODEL CONTINUES TO SHOW
DEVELOPMENT OF A BAND OF ACCUMULATING SNOW NEAR THIS AXIS...AND
RECENT RADAR TRENDS SHOW ONE DEVELOPING THIS PAST HOUR. THIS WILL
BE CLOSELY WATCHED...AND AMOUNTS OF SNOW MAY NEED TO BE ADDED
EARLY TODAY ALONG AND JUST NORTH OF INTERSTATE 80.
ERVIN
&&
.SYNOPSIS...
ISSUED AT 236 AM CST SAT JAN 4 2014
THE LATEST SURFACE ANALYSIS SHOWS A COLD FRONT FROM THE MINNESOTA
ARROWHEAD SOUTHWEST THROUGH SOUTHEASTERN SOUTH DAKOTA INTO SOUTH
CENTRAL NEBRASKA. STRONG SOUTHERLY FLOW CONTINUED AHEAD OF THE
FRONT CAUSING SOME PATCHY BLOWING SNOW OVER THE MID MISSISSIPPI
VALLEY. PRECIPITATION WITH THE COLD FRONT WAS MAINLY FOCUSED OVER
NORTHEAST MINNESOTA AND NORTHERN WISCONSIN JUST AHEAD OF A WAVE
ALONG THE BOUNDARY. THE 00Z H8 ANALYSIS HAD THE 850 COLD FRONT FROM
THE EASTERN DAKOTAS INTO THE WESTERN NEBRASKA WITH A WEDGE OF WARM
AIR NOSING INTO NORTHERN SOUTH DAKOTA. THE COLDER AIR AS STILL
BOTTLED UP ALONG THE CANADIAN BORDER. AT 500MB A BROAD TROF WAS
LOCATED OVER THE NORTHERN ROCKIES WITH A CLOSED LOW OVER NORTHERN
ALBERTA. AN IMPRESSIVE AREA OF HEIGHT FALLS...LOCATED AHEAD OF THE
CLOSED LOW...EXTENDED FROM SASKATCHEWAN INTO THE CENTRAL ROCKIES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 236 AM CST SAT JAN 4 2014
THE SURFACE COLD FRONT WILL MOVE THROUGH THE CWFA THIS MORNING AND
EARLY THIS AFTERNOON. MODELS ARE CONSISTENT SHOWING THE
PRECIPITATION/SNOW OCCURRING BEHIND THE FRONT AND DEVELOPING AS THE
FRONT MOVES THROUGH THE REGION. THE LATEST PROGS SUGGEST THE SNOW
WILL BE DEVELOPING OVER THE NORTHWEST CWA THIS MORNING...AND THEN
BECOME MORE ORGANIZED/WIDESPREAD DURING THE LATE AFTERNOON AND
EVENING OVER THE SOUTHEASTERN HALF OF THE FORECAST AREA. KEPT
CHANCE POPS OVER THE NORTHWEST THIS MORNING. POPS WERE SHIFTED TO
THE SOUTHEAST AND INCREASED TO LIKELY/CATEGORICAL DURING THE
AFTERNOON AND OVERNIGHT. LOOKING AT FORCING WITH THE
BOUNDARY...MODEL PROGS SHOWN A PROLONGED PERIOD OF FGEN OVER THE
AREA THIS AFTERNOON INTO TONIGHT...BUT IT DOES NOT LOOK THAT
ORGANIZED. TIME SECTIONS ARE SIMILAR...DEPICTING A PROLONGED PERIOD
OF AT LEAST MID LEVEL WEAK LIFT. WITH THE FORCING LACKING GOOD
ORGANIZATION HAVE OPTED TO KEEP PRECIPITATION AMOUNTS IN LINE WITH
THE DRIER GFS/ECMWF PROGS WITH PRECIP AMOUNTS UP TO A QUARTER OF AN
INCH OVER THE SOUTHEAST HALF OF THE CWFA. USING SNOW TO LIQUID
RATIOS AROUND 16 TO 1 THAT YIELD UP TO 3 INCHES OF SNOW BY SUNDAY
MORNING OVER THE SOUTHEAST HALF WITH THE HIGHER AMOUNTS OVER THE FAR
SOUTHEAST CORNER. WITH THESE FORECAST SNOW AMOUNTS AND WINDS NOT
EXPECTED TO BE VERY STRONG...SIGNIFICANT BLOWING SNOW SHOULD NOT BE
A CONCERN. NO WINTER WX ADVISORY IS PLANNED AT THIS TIME FOR THIS
AFTERNOON OR TONIGHT.
AS FOR TEMPERATURES TODAY...HIGHS SHOULD BE REACHED EARLY WITH
SLOWLY FALLING TEMPERATURES DURING THE AFTERNOON. BY SUNDAY MORNING
READINGS WILL BE BACK IN THE SINGLE DIGITS WITH SUB ZERO TEMPS OVER
THE NORTHWEST. WIND CHILLS WILL BE APPROACHING -30 BY 6AM SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 236 AM CST SAT JAN 4 2014
THIS MORNINGS 20S WILL BE A DISTANT MEMORY SUNDAY MORNING...AS
INCREASINGLY STRONG ARCTIC COLD ADVECTION WILL BE WELL UNDERWAY. THE
MAIN CHALLENGE DURING THIS INITIAL PERIOD WILL BE ENDING ANY SNOW IN
THE EAST...AND TIMING ON THE ONSET OF WIND CHILL HEADLINES. THE
HEADLINES FOR WIND CHILL ARE THE HIGHEST CONCERN...AND KEEPING THE
MESSAGE CONSISTENT AND AS SIMPLE AS POSSIBLE HAS BEEN OUR GOAL ON
THIS ISSUANCE. PURE METEOROLOGICALLY...SUNDAY WILL BE MAINLY AN
ADVISORY DAY UNTIL LATE AFTERNOON...AS WILL TUESDAY MID
MORNING...HOWEVER...THIS IS JUST BRACKETS ON WHAT IS A HIGH
CONFIDENCE AND LIFE THREATENING WIND CHILL EVENT. A WARNING WILL BE
ISSUED FOR THE PRIOR WATCH COUNTIES IN THE NORTHWEST STARTING AT 6
AM SUNDAY MORNING...THEN THE REMAINDER OF COUNTIES WILL BEGIN AT
NOON SUNDAY. THIS ROUGHLY MATCHES THE WATCH...AND KEEP THE MESSAGE
CONSISTENT. BY FAR...THE WORST CONDITIONS WILL BE SUNDAY NIGHT
THROUGH MONDAY NIGHT...WITH A PROLONGED PERIOD OF -35 TO -45 CHILLS
AREA WIDE. THE NORTH HALF SHOULD MAX OUR WIND CHILL INTENSITY IN THE
-48 TO -53 BETWEEN 4 AM MONDAY AND 9 AM MONDAY. ACTUAL TEMPERATURES
WILL SLOWLY FALL SUNDAY WITHIN THE -5 TO +7 TEMPERATURE RANGE. BY
SUNDAY AT 6 PM...WE ARE ALREADY EXPECTING ACTUAL TEMPERATURES TO BY
-10 NORTHWEST TO -2 SOUTHEAST. LOWS SUNDAY NIGHT APPEAR SET THROUGH
PURE COLD ADVECTION/NO RADIATIONAL COOLING TO REACH -19 TO -25 IN
THE NORTH 1/2 TO -14 TO -19 IN THE SOUTH HALF. WINDS OVERNIGHT WILL
BE STRONG...SUSTAINED AROUND 20 TO 25 MPH...GUSTING TO 30 TO 35 MPH.
THIS IS WHY THE WIND CHILLS WILL BE SO EXCRUCIATINGLY COLD. SIMILAR
WINDS WILL CONTINUE THROUGH EARLY MONDAY EVENING...BEFORE SLOWLY
BACKING DOWN. IF ANYTHING...THIS MAY BE SLIGHTLY UNDERDONE GIVEN THE
WHOPPING GRADIENT BETWEEN A STRENGTHENING SUB 1000MB LOW IN THE
EASTERN GREAT LAKES...AND A ASTOUNDINGLY STRONG 1050+ MB HIGH
ENTERING MONTANA. THIS GRADIENT MAY CREATE LEGITIMATE BLOWING SNOW
THREAT SUNDAY AND SUNDAY NIGHT. IN ADDITION...INTENSE ADVECTION OF
ARCTIC AIR WILL KEEP THE BOUNDARY LAYER MIXED CONTINUOUSLY...WHICH
OFTEN IS UNDERPLAYED BY MODELS.
BEYOND TUESDAY...A WARM UP IS FORECAST...BUT IT WILL TAKE SEVERAL
DAYS TO RID THE REGION OF ARCTIC AIR. SOME OVER RUNNING SNOWS IS A
GROWING THREAT FOR WEDNESDAY AND THURSDAY...BUT AT THIS
POINT...MODELS DO NOT SHOW STRONG ENOUGH DYNAMICS TO CREATE MUCH OF
A STORM THREAT.
ERVIN
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1155 AM CST SAT JAN 4 2014
A VERY STRONG COLD FRONT WILL CONTINUE TO SWEEP THROUGH EASTERN
IOWA AND NORTHWEST ILLINOIS THIS AFTERNOON...FOLLOWED BY A MUCH
STRONGER SURGE OF ARCTIC AIR SUNDAY. SOUTHWEST WINDS WILL BECOME
NORTHWEST AT 15 TO 25 KNOTS BEHIND THE FRONT. LIGHT SNOW SHOULD
DEVELOP JUST BEHIND THE FRONT...AND BECOME WIDESPREAD FOR A TIME
IN SOUTHEAST IOWA AND ILLINOIS. MLI AND BRL WILL LIKELY SEE IFR
VISIBILITIES IN SNOW TOWARD VERY LATE AFTERNOON AND EARLY EVENING.
THIS SNOW MAY CONTINUE THROUGH MID MORNING SUNDAY BEFORE ENDING IN
ILLINOIS. IT IS UNLIKELY THAT MLI AND BRL WILL SEE SNOW CONTINUE
BEYOND 12Z SUNDAY. VERY COLD AIR WILL BE FOUND THROUGH THE DAY
SUNDAY. STRONG NORTHWEST WINDS OF 20 TO 30 KTS WILL CONTINUE FROM
LATER TONIGHT THROUGH MONDAY NIGHT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WIND CHILL WARNING FROM 6 AM SUNDAY TO NOON CST TUESDAY FOR
BENTON-BUCHANAN-DELAWARE-DUBUQUE-JACKSON-JONES-LINN.
WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
CEDAR-CLINTON-DES MOINES-HENRY IA-IOWA-JEFFERSON-JOHNSON-
KEOKUK-LEE-LOUISA-MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM CST
SUNDAY FOR LEE.
IL...WIND CHILL WARNING FROM 6 AM SUNDAY TO NOON CST TUESDAY FOR JO
DAVIESS.
WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
BUREAU-CARROLL-HANCOCK-HENDERSON-HENRY IL-MCDONOUGH-MERCER-
PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM CST
SUNDAY FOR BUREAU-HANCOCK-HENDERSON-HENRY IL-MCDONOUGH-
PUTNAM-WARREN.
MO...WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
CLARK-SCOTLAND.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM CST
SUNDAY FOR CLARK-SCOTLAND.
&&
$$
UPDATE...HAASE
SYNOPSIS...DLF
SHORT TERM...DLF
LONG TERM...ERVIN
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1158 AM CST SAT JAN 4 2014
.UPDATE...
ISSUED AT 1155 AM CST SAT JAN 4 2014
ARCTIC FRONT LATE THIS MORNING EXTENDED FROM JUST WEST OF DUBUQUE
TO IOWA CITY AND THEN TO KANSAS CITY. AHEAD OF THE FRONT
TEMPERATURES HAVE PUSHED INTO THE LOWER TO MID 30S BUT BEHIND THE
FRONT READINGS HAD FALLEN TO 12 ABOVE IN NW IA BUT WERE BELOW ZERO
FROM ND TO NORTHERN MN. THE FRONT WILL CONTINUE TO PUSH EASTWARD
ACROSS THE CWA AS THE AFTERNOON PROGRESSES WITH FALLING TEMPERATURES.
BAND OF LIGHT SNOW HAS DEVELOPED AHEAD OF THE FRONT IN EASTERN IA
AND NW IL AND HAVE RAISED POPS TO LIKELY WITH ACCUMULATIONS OF
LESS THAN AN INCH THIS AFTERNOON.
UPDATE ISSUED AT 722 AM CST SAT JAN 4 2014
I HAVE SENT A FEW UPDATES TO CLOUD AND PRECIPITATION TRENDS. THE
LARGEST SIGNIFICANCE IS TO GREATLY INCREASE MORNING POPS ALONG AND
NORTH OF INTERSTATE 80. THE RAP MODEL CONTINUES TO SHOW
DEVELOPMENT OF A BAND OF ACCUMULATING SNOW NEAR THIS AXIS...AND
RECENT RADAR TRENDS SHOW ONE DEVELOPING THIS PAST HOUR. THIS WILL
BE CLOSELY WATCHED...AND AMOUNTS OF SNOW MAY NEED TO BE ADDED
EARLY TODAY ALONG AND JUST NORTH OF INTERSTATE 80.
ERVIN
&&
.SYNOPSIS...
ISSUED AT 236 AM CST SAT JAN 4 2014
THE LATEST SURFACE ANALYSIS SHOWS A COLD FRONT FROM THE MINNESOTA
ARROWHEAD SOUTHWEST THROUGH SOUTHEASTERN SOUTH DAKOTA INTO SOUTH
CENTRAL NEBRASKA. STRONG SOUTHERLY FLOW CONTINUED AHEAD OF THE
FRONT CAUSING SOME PATCHY BLOWING SNOW OVER THE MID MISSISSIPPI
VALLEY. PRECIPITATION WITH THE COLD FRONT WAS MAINLY FOCUSED OVER
NORTHEAST MINNESOTA AND NORTHERN WISCONSIN JUST AHEAD OF A WAVE
ALONG THE BOUNDARY. THE 00Z H8 ANALYSIS HAD THE 850 COLD FRONT FROM
THE EASTERN DAKOTAS INTO THE WESTERN NEBRASKA WITH A WEDGE OF WARM
AIR NOSING INTO NORTHERN SOUTH DAKOTA. THE COLDER AIR AS STILL
BOTTLED UP ALONG THE CANADIAN BORDER. AT 500MB A BROAD TROF WAS
LOCATED OVER THE NORTHERN ROCKIES WITH A CLOSED LOW OVER NORTHERN
ALBERTA. AN IMPRESSIVE AREA OF HEIGHT FALLS...LOCATED AHEAD OF THE
CLOSED LOW...EXTENDED FROM SASKATCHEWAN INTO THE CENTRAL ROCKIES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 236 AM CST SAT JAN 4 2014
THE SURFACE COLD FRONT WILL MOVE THROUGH THE CWFA THIS MORNING AND
EARLY THIS AFTERNOON. MODELS ARE CONSISTENT SHOWING THE
PRECIPITATION/SNOW OCCURRING BEHIND THE FRONT AND DEVELOPING AS THE
FRONT MOVES THROUGH THE REGION. THE LATEST PROGS SUGGEST THE SNOW
WILL BE DEVELOPING OVER THE NORTHWEST CWA THIS MORNING...AND THEN
BECOME MORE ORGANIZED/WIDESPREAD DURING THE LATE AFTERNOON AND
EVENING OVER THE SOUTHEASTERN HALF OF THE FORECAST AREA. KEPT
CHANCE POPS OVER THE NORTHWEST THIS MORNING. POPS WERE SHIFTED TO
THE SOUTHEAST AND INCREASED TO LIKELY/CATEGORICAL DURING THE
AFTERNOON AND OVERNIGHT. LOOKING AT FORCING WITH THE
BOUNDARY...MODEL PROGS SHOWN A PROLONGED PERIOD OF FGEN OVER THE
AREA THIS AFTERNOON INTO TONIGHT...BUT IT DOES NOT LOOK THAT
ORGANIZED. TIME SECTIONS ARE SIMILAR...DEPICTING A PROLONGED PERIOD
OF AT LEAST MID LEVEL WEAK LIFT. WITH THE FORCING LACKING GOOD
ORGANIZATION HAVE OPTED TO KEEP PRECIPITATION AMOUNTS IN LINE WITH
THE DRIER GFS/ECMWF PROGS WITH PRECIP AMOUNTS UP TO A QUARTER OF AN
INCH OVER THE SOUTHEAST HALF OF THE CWFA. USING SNOW TO LIQUID
RATIOS AROUND 16 TO 1 THAT YIELD UP TO 3 INCHES OF SNOW BY SUNDAY
MORNING OVER THE SOUTHEAST HALF WITH THE HIGHER AMOUNTS OVER THE FAR
SOUTHEAST CORNER. WITH THESE FORECAST SNOW AMOUNTS AND WINDS NOT
EXPECTED TO BE VERY STRONG...SIGNIFICANT BLOWING SNOW SHOULD NOT BE
A CONCERN. NO WINTER WX ADVISORY IS PLANNED AT THIS TIME FOR THIS
AFTERNOON OR TONIGHT.
AS FOR TEMPERATURES TODAY...HIGHS SHOULD BE REACHED EARLY WITH
SLOWLY FALLING TEMPERATURES DURING THE AFTERNOON. BY SUNDAY MORNING
READINGS WILL BE BACK IN THE SINGLE DIGITS WITH SUB ZERO TEMPS OVER
THE NORTHWEST. WIND CHILLS WILL BE APPROACHING -30 BY 6AM SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 236 AM CST SAT JAN 4 2014
THIS MORNINGS 20S WILL BE A DISTANT MEMORY SUNDAY MORNING...AS
INCREASINGLY STRONG ARCTIC COLD ADVECTION WILL BE WELL UNDERWAY. THE
MAIN CHALLENGE DURING THIS INITIAL PERIOD WILL BE ENDING ANY SNOW IN
THE EAST...AND TIMING ON THE ONSET OF WIND CHILL HEADLINES. THE
HEADLINES FOR WIND CHILL ARE THE HIGHEST CONCERN...AND KEEPING THE
MESSAGE CONSISTENT AND AS SIMPLE AS POSSIBLE HAS BEEN OUR GOAL ON
THIS ISSUANCE. PURE METEOROLOGICALLY...SUNDAY WILL BE MAINLY AN
ADVISORY DAY UNTIL LATE AFTERNOON...AS WILL TUESDAY MID
MORNING...HOWEVER...THIS IS JUST BRACKETS ON WHAT IS A HIGH
CONFIDENCE AND LIFE THREATENING WIND CHILL EVENT. A WARNING WILL BE
ISSUED FOR THE PRIOR WATCH COUNTIES IN THE NORTHWEST STARTING AT 6
AM SUNDAY MORNING...THEN THE REMAINDER OF COUNTIES WILL BEGIN AT
NOON SUNDAY. THIS ROUGHLY MATCHES THE WATCH...AND KEEP THE MESSAGE
CONSISTENT. BY FAR...THE WORST CONDITIONS WILL BE SUNDAY NIGHT
THROUGH MONDAY NIGHT...WITH A PROLONGED PERIOD OF -35 TO -45 CHILLS
AREA WIDE. THE NORTH HALF SHOULD MAX OUR WIND CHILL INTENSITY IN THE
-48 TO -53 BETWEEN 4 AM MONDAY AND 9 AM MONDAY. ACTUAL TEMPERATURES
WILL SLOWLY FALL SUNDAY WITHIN THE -5 TO +7 TEMPERATURE RANGE. BY
SUNDAY AT 6 PM...WE ARE ALREADY EXPECTING ACTUAL TEMPERATURES TO BY
-10 NORTHWEST TO -2 SOUTHEAST. LOWS SUNDAY NIGHT APPEAR SET THROUGH
PURE COLD ADVECTION/NO RADIATIONAL COOLING TO REACH -19 TO -25 IN
THE NORTH 1/2 TO -14 TO -19 IN THE SOUTH HALF. WINDS OVERNIGHT WILL
BE STRONG...SUSTAINED AROUND 20 TO 25 MPH...GUSTING TO 30 TO 35 MPH.
THIS IS WHY THE WIND CHILLS WILL BE SO EXCRUCIATINGLY COLD. SIMILAR
WINDS WILL CONTINUE THROUGH EARLY MONDAY EVENING...BEFORE SLOWLY
BACKING DOWN. IF ANYTHING...THIS MAY BE SLIGHTLY UNDERDONE GIVEN THE
WHOPPING GRADIENT BETWEEN A STRENGTHENING SUB 1000MB LOW IN THE
EASTERN GREAT LAKES...AND A ASTOUNDINGLY STRONG 1050+ MB HIGH
ENTERING MONTANA. THIS GRADIENT MAY CREATE LEGITIMATE BLOWING SNOW
THREAT SUNDAY AND SUNDAY NIGHT. IN ADDITION...INTENSE ADVECTION OF
ARCTIC AIR WILL KEEP THE BOUNDARY LAYER MIXED CONTINUOUSLY...WHICH
OFTEN IS UNDERPLAYED BY MODELS.
BEYOND TUESDAY...A WARM UP IS FORECAST...BUT IT WILL TAKE SEVERAL
DAYS TO RID THE REGION OF ARCTIC AIR. SOME OVER RUNNING SNOWS IS A
GROWING THREAT FOR WEDNESDAY AND THURSDAY...BUT AT THIS
POINT...MODELS DO NOT SHOW STRONG ENOUGH DYNAMICS TO CREATE MUCH OF
A STORM THREAT.
ERVIN
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1155 AM CST SAT JAN 4 2014
A VERY STRONG COLD FRONT WILL CONTINUE TO SWEEP THROUGH EASTERN
IOWA AND NORTHWEST ILLINOIS THIS AFTERNOON...FOLLOWED BY A MUCH
STRONGER SURGE OF ARCTIC AIR SUNDAY. SOUTHWEST WINDS WILL BECOME
NORTHWEST AT 15 TO 25 KNOTS BEHIND THE FRONT. LIGHT SNOW SHOULD
DEVELOP JUST BEHIND THE FRONT...AND BECOME WIDESPREAD FOR A TIME
IN SOUTHEAST IOWA AND ILLINOIS. MLI AND BRL WILL LIKELY SEE IFR
VISIBILITIES IN SNOW TOWARD VERY LATE AFTERNOON AND EARLY EVENING.
THIS SNOW MAY CONTINUE THROUGH MID MORNING SUNDAY BEFORE ENDING IN
ILLINOIS. IT IS UNLIKELY THAT MLI AND BRL WILL SEE SNOW CONTINUE
BEYOND 12Z SUNDAY. VERY COLD AIR WILL BE FOUND THROUGH THE DAY
SUNDAY. STRONG NORTHWEST WINDS OF 20 TO 30 KTS WILL CONTINUE FROM
LATER TONIGHT THROUGH MONDAY NIGHT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WIND CHILL WARNING FROM 6 AM SUNDAY TO NOON CST TUESDAY FOR
BENTON-BUCHANAN-DELAWARE-DUBUQUE-JACKSON-JONES-LINN.
WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
CEDAR-CLINTON-DES MOINES-HENRY IA-IOWA-JEFFERSON-JOHNSON-
KEOKUK-LEE-LOUISA-MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...WIND CHILL WARNING FROM 6 AM SUNDAY TO NOON CST TUESDAY FOR JO
DAVIESS.
WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
BUREAU-CARROLL-HANCOCK-HENDERSON-HENRY IL-MCDONOUGH-MERCER-
PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
CLARK-SCOTLAND.
&&
$$
UPDATE...HAASE
SYNOPSIS...DLF
SHORT TERM...DLF
LONG TERM...ERVIN
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
436 PM EST SAT JAN 4 2014
.UPDATE...
ISSUED AT 709 AM EST SAT JAN 4 2014
EXTENDED GOING WINTER STORM WARNING FOR ALGER COUNTY THRU 15Z WITH
SGNFT RADAR ECHOES LINGERING OVER THAT AREA UNDER THE DPVA/H85-5
QVECTOR CNVGC AHEAD OF SHRTWV MOVING E INTO THE UPR LKS. LARGER
SCALE SUBSIDENCE/MID LVL DRYING IN THE WAKE OF THIS DISTURBANCE WL
CAUSE THE SN TO DIMINISH IN ALGER COUNTY BY LATE MRNG.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EST SAT JAN 4 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW VIGOROUS SHRTWV
SHIFTING E FM MN INTO THE UPR GRT LKS. THIS DISTURBANCE IS REFLECTED
BY A SFC LO PRES TROF IN MN...WHILE ANOTHER WEAKER DISTURBANCE/LO
PRES IS SHIFTING THRU ONTARIO. ALTHOUGH THERE IS NO WELL DEFINED SFC
LO PRES CENTER...THE SHARP PRES GRADIENT BTWN THE GENERAL LO PRES
TROF TO THE W AND RETREATING SFC HI PRES OVER THE MID ATLANTIC
STATES IS SUPPORTING A VERY STRONG SW FLOW INTO THE UPR LKS...WITH
THE 00Z GRB RAOB SHOWING AN IMPRESSIVE SW WIND UP TO 70 KTS AT H85.
THE ISENTROPIC ASCENT ASSOCIATED WITH THIS STRONG SW FLOW SUPPORTED
A BAND OF HEAVIER SN THAT IMPACTED MAINLY THE NRN PORTION OF UPR MI
AS WELL AS AREAS DOWNWIND OF LK MI...WHERE THE FLOW OFF THE WATER
IN THE PRESENCE OF THE RETREATING ARCTIC AIRMASS ALLOWED FOR SGNFT
LK ENHANCEMENT/SN FALL RATES UP TO AN INCH PER HR. THE LLVL
DESTABILIZATION ALSO SHARPENED LLVL LAPSE RATES AND ALLOWED FOR SFC
WIND GUSTS NEAR THE BAY OF GREEN BAY/LK MI TO REACH AS HI AS 68 MPH
AT A SITE NEAR THOMPSON IN SCHOOLCRAFT COUNTY. THE AREA OF STRONGEST
LLVL WINDS/SHARPER ISENTROPIC ASCENT/SUPPORTING CENTER OF VIGOROUS
H85-5 QVECTOR CNVGC IS TENDING TO DRIFT E EARLY THIS MRNG...SO THE
SW WINDS/SN INTENSITY ARE DIMINSING A BIT. BUT ANOTHER AREA OF SN TO
THE W ASSOCIATED WITH THE DPVA/ACCOMPANYING DEEP LYR QVECTOR CNVGC
ACCOMPANYING THE MN SHRTWV IS TENDING TO PUSH BACK INTO THE AREA.
LOOKING FARTHER TO THE W...COLDER AIR IS PLOWING BACK INTO THE NRN
PLAINS BEHIND A COLD FNT SWEEPING THRU MN. AN EVEN COLDER ARCTIC
AIRMASS ASSOCIATED WITH ANOTHER SHRTWV DIGGING SEWD THRU
ALBERTA/SASKATCHEWAN IS APRCHG THE NRN PLAINS.
MAIN FCST CONCERNS IN THE SHORT TERM ARE POPS ASSOCIATED WITH APRCHG
MN SHRTWV AND THEN TEMPS/LES AS THE MUCH COLDER AIR UPSTREAM IN THE
WAKE OF THIS DISTURBANCE SURGES INTO THE UPR LKS.
TODAY...AREA OF DPVA/DEEP LYR QVECTOR CNVGC SUPPORTING THE AREA OF
WDSPREAD SN MOVING INTO THE WRN CWA EARLY THIS MRNG IS PROGGED TO
MOVE OUT OF THE ERN CWA BTWN 15Z-18Z...SO TRENDED SYNOPTIC SCALE
POPS DOWN W-E IN LINE WITH GOING FCST WITH ARRIVAL OF DNVA/CAD/DEEP
LYR QVECTOR DVGC AND STRONG SUBSIDENCE/MID LVL DRYING IN THE WAKE OF
MN SHRTWV PASSAGE. BUT OVER THE W...LES WL DVLP IN THE COLD NW FLOW
BEHIND THE FROPA AS H85 TEMPS FALL TOWARD -18C BY 00Z SUN.
HOWEVER...FCST SUBSIDENCE IS PROGGED TO DROP THE INVRN BASE TO AS LO
AS 3-4K FT. NAM/GFS/LOCAL WRF ARW FCST SNGS ALSO INDICATE GENERAL
SUBSIDENCE IN THE MIXED LYR BLO THE INVRN...SO LES AMOUNTS SHOULD BE
RELATIVELY LGT. HI RES MODELS INDICATE THE MORE FOCUSED LLVL CNVGC
WL IMPACT NRN ONTONAGON/SRN HOUGHTON COUNTY. ALTHOUGH TEMPS WL RISE
INTO THE 20S THIS MRNG BEFORE SFC COLD FNT NOW IN MN CLEARS THE CWA
W-E AND NEWBERRY IN THE AFTN...TEMPS WL FALL W-E FOLLOWING THE FROPA
WITH THE ARRIVAL OF THE COLDER H85 TEMPS.
TNGT...COLDER AIR ASSOCIATED WITH DIGGING SHRTWV IN WRN CANADA/
DEEPENING ARCTIC BRANCH IN THE PLAINS IS PROGGED TO STEADILY ADVECT
INTO THE UPR GRT LKS IN STEADY WNW FLOW/H925 WINDS 20-25KTS.
CONSENSUS OF FAVORED MODELS INDICATES H85 TEMPS WL FALL TO ARND -25C
OVER THE WRN CWA AND -18C OVER THE E BY 12Z SUN. ALTHOUGH THIS CHILL
WITH H85/LK WATER TEMP DIFFERENCE OVER 20C WL SUPPORT LES... HIER
RES MODELS ARE INDICATING LO INVRN BASE MAINTAINED BY ONGOING
SUBIDENCE THAT EXTENDS INTO THE MIXED LYR WL HAMPER LES AMOUNTS. SO
A RELATIVELY HI POP/LO QPF SCENARIO SEEMS TO BE IN STORE. THE
ARRIVING CHILL WL ALSO PUSH THE DGZ BLO THE SFC OVER THE WRN CWA...
SO THIS POOR SN GROWTH WL ALSO HAMPER LES AMOUNTS. BUT THE SMALL SN
FLAKE SIZE WL BE EFFICIENT AT REDUCING VSBY...ESPECIALLY AT EXPOSED
LOCATIONS NEAR LK SUP. EXPECT TEMPS OVER THE INTERIOR W HALF...WHERE
THE INCOMING AIRMASS WL BE MODIFIED LEAST BY THE WARMING OF LK
SUP...TO FALL AS LO AS 15 TO 20 BLO ZERO. WITH APRNT TEMPS LIKELY TO
FALL TO -25 TO -35...OPTED TO ISSUE A WIND CHILL ADVY FOR LATE TNGT
THRU SUN MRNG FOR THE INTERIOR W HALF COUNTIES EVEN THOUGH WIND
SPEEDS MAY NOT HOLD AOA THE THRESHOLD OF 10 MPH.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 435 PM EST SAT JAN 4 2014
NAM SHOWS A DEEP 500 MB TROUGH OVER THE CENTRAL U.S. 00Z MON WITH A
STRONG SOUTHERN STREAM SHORTWAVE NEAR CHICAGO 00Z MON. THE 500 MB
TROUGH MOVES EAST SUN NIGHT WITH THE TROUGH AXIS PUSHING ACROSS THE
CWA ON MON BEFORE THE TROUGH AND UPPER LEVEL LOWS PULL NORTHEAST ON
WED. WHAT THIS WILL MEAN IS VERY COLD AIR MOVING ACROSS THE AREA.
12Z NAM SEEMS TO BE FURTHER NORTHWEST WITH THE TRACK OF THE SFC LOW
FROM WHAT THE ECMWF HAS FOR SUNDAY NIGHT INTO MON. GFS AND ECMWF
SHOW SOME 850-500 MB Q-VECTOR CONVERGENCE SUN NIGHT AND ARE ALSO
FURTHER EAST WITH THE SFC LOW TRACK THAN THE NAM IS. SFC LOW 00Z MON
WITH ECMWF AND GFS IS OVER CENTRAL OHIO WHILE NAM IS OVER WESTERN
OHIO AND AT 06Z MON SFC LOW OFF THE ECMWF AND GFS IS NEAR BUFFALO
NEW YORK WHILE NAM HAS IT NEAR KITCHENER ONTARIO. WILL GO WITH THE
FARTHER EAST TRACK WHICH WILL NOT MEAN MUCH EXCEPT THAT THE SYSTEM
SNOW WILL STAY OUT OF THE AREA AND LAKE EFFECT SNOW SHOWERS WILL BE
THE RULE INSTEAD FOR THIS FORECAST PERIOD WITH ACCUMULATIONS IN THE
NORTHWEST WIND AFFECTED SNOW BELTS. MAIN STORY WILL BE THE COLD
TEMPERATURES AND THE WIND SPEEDS. WIND SPEEDS WILL STAY UP SUN NIGHT
THROUGH TUE NIGHT WITH COLD TEMPERATURES. WIND CHILL VALUES WILL
FALL TO AS LOW AS -50F AND WILL GO WITH WIND CHILL WARNINGS FOR MOST
OF THE AREA. IF WINDS ARE LESS THAN FORECASTED...COULD GET COLDER
AND IF WINDS STAY UP...LOW TEMPERATURES WOULD BE WARMER. EITHER
WAY...WIND CHILL VALUES LOOK TO BE IN THE WARNING CRITERIA AND WILL
GO WITH WIND CHILL WARNINGS. DID NOT MAKE TOO MANY CHANGES TO THE
GOING FORECAST FOR TEMPERATURES EXCEPT FOR A FEW MINOR TWEAKS HERE
AND THERE AND DID NOT MAKE TOO MANY CHANGES TO THE POPS EITHER.
IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH 12Z WED
OVER THE U.S. WITH COLD AIR CONTINUING TO MOVE ACROSS THE AREA...BUT
SOME MODIFICATION HAS ALREADY TAKEN PLACE AS THE POLAR VORTEX AND
EXTREME COLD AIR WILL HAVE MOVED OFF TO THE NORTHEAST BY THAT TIME.
NOT MUCH CHANGES FOR 12Z THU FOR THE UPPER PATTERN. A DEEPENING
TROUGH MOVES INTO THE ROCKIES 12Z FRI WHICH MOVES INTO THE UPPER
GREAT LAKES 12Z SAT WITH WARMER AIR MOVING INTO THE AREA FRI INTO
SAT. TEMPERATURES WILL ACTUALLY GO ABOVE NORMAL FOR FRI INTO
SATURDAY. WILL GO DRY FOR THU NIGHT AND FRIDAY AS WINDS ARE
SOUTHWEST AT THAT TIME AND PUSH THE LAKE EFFECT TO THE NORTH OF THE
AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1246 PM EST SAT JAN 4 2014
WITH INCREASINGLY COLDER AIR FLOWING INTO THE UPPER LAKES...LAKE
EFFECT SNOW SHOWERS WILL BE THE RULE OFF LAKE SUPERIOR IN W TO NW
FLOW. KIWD WILL BE NEAR THE SRN EDGE OF THE LAKE EFFECT SNOW
SHOWERS. IN GENERAL...MVFR CONDITIONS SHOULD PREVAIL THRU THE FCST
PERIOD. HOWEVER...EXPECT SOME PERIODS OF IFR FOR THE NEXT FEW HRS
BEFORE SUBSIDENCE/DRYING IN THE WAKE OF THE COLD FRONT THAT PASSED
EARLIER TODAY BECOME MORE DOMINANT. AT KCMX...PERSISTENT LAKE EFFECT
SNOW SHOWERS SHOULD LEAD TO PREVAILING IFR CONDITIONS. HOWEVER...
THERE WILL BE PERIODS OF LIFR FOR MUCH OF THE AFTN. AS AIR MASS
BECOMES EXTREMELY COLD...SNOWFLAKES WILL BECOME SMALL...LEADING TO A
TREND FOR INCREASINGLY LOWER VIS WITH TIME SUN/MON. AS A
RESULT...THERE MAY BE AN EXTENDED PERIOD OF LIFR VIS DEVELOPING AT
SOME POINT SUN AT KCMX. AT KSAW...OCNL -SHSN JUST BEHIND PASSING
COLD FRONT WILL LEAD TO MVFR/OCNL IFR FOR THE NEXT COUPLE OF HRS.
THEN...THERE SHOULD BE ENOUGH DRYING/SUBSIDENCE TO CAUSE CONDITIONS
TO IMPROVE TO VFR LATER TODAY/TONIGHT IN THE PRESENCE OF A DOWNSLOPE
WNW FLOW. MVFR CONDITIONS MAY RETURN SUN MORNING AS WINDS VEER A
LITTLE MORE NORTHERLY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 PM EST SAT JAN 4 2014
EVEN THOUGH THE NW WINDS WILL BE UP TO ONLY 25-30 KTS TONIGHT...THE
ARRIVAL OF BITTERLY COLD ARCTIC AIR/SUFFICIENTLY HI WAVES WILL
RESULT IN WIDESPREAD HEAVY FREEZING SPRAY THROUGH TUESDAY NIGHT.
NEXT GALE EVENT WOULD BE NORTHWEST GALES TO 35 KNOTS OVER PORTIONS
OF CENTRAL AND EASTERN LAKE SUPERIOR MONDAY AFTERNOON THROUGH
TUESDAY EVENING. HIGH PRESSURE WILL RETURN WEDNESDAY INTO THURSDAY
AND BRING WINDS DOWN BELOW 20 KNOTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WARNING FROM 7 PM EST /6 PM CST/ SUNDAY TO 11 AM EST
/10 AM CST/ TUESDAY FOR MIZ001>005-009>013-084.
WIND CHILL ADVISORY FROM MIDNIGHT EST /11 PM CST/ TONIGHT TO 7
PM EST /6 PM CST/ SUNDAY FOR MIZ002-009-010-084.
WIND CHILL WARNING FROM 7 PM MONDAY TO 11 AM EST TUESDAY FOR
MIZ006-007-014-085.
WIND CHILL ADVISORY FROM 7 PM SUNDAY TO 1 PM EST MONDAY FOR
MIZ006-007-014-085.
WIND CHILL ADVISORY FROM MIDNIGHT EST /11 PM CST/ TONIGHT TO
NOON EST /11 AM CST/ SUNDAY FOR MIZ004-005-011.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 7 AM EST
WEDNESDAY FOR LSZ267.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ266-267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY
FOR LSZ162-263>266.
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST MONDAY FOR
LSZ243>245-248>251.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SHORT TERM...KC
LONG TERM...07
AVIATION...ROLFSON
MARINE...07
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
426 PM EST SAT JAN 4 2014
.UPDATE...
ISSUED AT 709 AM EST SAT JAN 4 2014
EXTENDED GOING WINTER STORM WARNING FOR ALGER COUNTY THRU 15Z WITH
SGNFT RADAR ECHOES LINGERING OVER THAT AREA UNDER THE DPVA/H85-5
QVECTOR CNVGC AHEAD OF SHRTWV MOVING E INTO THE UPR LKS. LARGER
SCALE SUBSIDENCE/MID LVL DRYING IN THE WAKE OF THIS DISTURBANCE WL
CAUSE THE SN TO DIMINISH IN ALGER COUNTY BY LATE MRNG.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EST SAT JAN 4 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW VIGOROUS SHRTWV
SHIFTING E FM MN INTO THE UPR GRT LKS. THIS DISTURBANCE IS REFLECTED
BY A SFC LO PRES TROF IN MN...WHILE ANOTHER WEAKER DISTURBANCE/LO
PRES IS SHIFTING THRU ONTARIO. ALTHOUGH THERE IS NO WELL DEFINED SFC
LO PRES CENTER...THE SHARP PRES GRADIENT BTWN THE GENERAL LO PRES
TROF TO THE W AND RETREATING SFC HI PRES OVER THE MID ATLANTIC
STATES IS SUPPORTING A VERY STRONG SW FLOW INTO THE UPR LKS...WITH
THE 00Z GRB RAOB SHOWING AN IMPRESSIVE SW WIND UP TO 70 KTS AT H85.
THE ISENTROPIC ASCENT ASSOCIATED WITH THIS STRONG SW FLOW SUPPORTED
A BAND OF HEAVIER SN THAT IMPACTED MAINLY THE NRN PORTION OF UPR MI
AS WELL AS AREAS DOWNWIND OF LK MI...WHERE THE FLOW OFF THE WATER
IN THE PRESENCE OF THE RETREATING ARCTIC AIRMASS ALLOWED FOR SGNFT
LK ENHANCEMENT/SN FALL RATES UP TO AN INCH PER HR. THE LLVL
DESTABILIZATION ALSO SHARPENED LLVL LAPSE RATES AND ALLOWED FOR SFC
WIND GUSTS NEAR THE BAY OF GREEN BAY/LK MI TO REACH AS HI AS 68 MPH
AT A SITE NEAR THOMPSON IN SCHOOLCRAFT COUNTY. THE AREA OF STRONGEST
LLVL WINDS/SHARPER ISENTROPIC ASCENT/SUPPORTING CENTER OF VIGOROUS
H85-5 QVECTOR CNVGC IS TENDING TO DRIFT E EARLY THIS MRNG...SO THE
SW WINDS/SN INTENSITY ARE DIMINSING A BIT. BUT ANOTHER AREA OF SN TO
THE W ASSOCIATED WITH THE DPVA/ACCOMPANYING DEEP LYR QVECTOR CNVGC
ACCOMPANYING THE MN SHRTWV IS TENDING TO PUSH BACK INTO THE AREA.
LOOKING FARTHER TO THE W...COLDER AIR IS PLOWING BACK INTO THE NRN
PLAINS BEHIND A COLD FNT SWEEPING THRU MN. AN EVEN COLDER ARCTIC
AIRMASS ASSOCIATED WITH ANOTHER SHRTWV DIGGING SEWD THRU
ALBERTA/SASKATCHEWAN IS APRCHG THE NRN PLAINS.
MAIN FCST CONCERNS IN THE SHORT TERM ARE POPS ASSOCIATED WITH APRCHG
MN SHRTWV AND THEN TEMPS/LES AS THE MUCH COLDER AIR UPSTREAM IN THE
WAKE OF THIS DISTURBANCE SURGES INTO THE UPR LKS.
TODAY...AREA OF DPVA/DEEP LYR QVECTOR CNVGC SUPPORTING THE AREA OF
WDSPREAD SN MOVING INTO THE WRN CWA EARLY THIS MRNG IS PROGGED TO
MOVE OUT OF THE ERN CWA BTWN 15Z-18Z...SO TRENDED SYNOPTIC SCALE
POPS DOWN W-E IN LINE WITH GOING FCST WITH ARRIVAL OF DNVA/CAD/DEEP
LYR QVECTOR DVGC AND STRONG SUBSIDENCE/MID LVL DRYING IN THE WAKE OF
MN SHRTWV PASSAGE. BUT OVER THE W...LES WL DVLP IN THE COLD NW FLOW
BEHIND THE FROPA AS H85 TEMPS FALL TOWARD -18C BY 00Z SUN.
HOWEVER...FCST SUBSIDENCE IS PROGGED TO DROP THE INVRN BASE TO AS LO
AS 3-4K FT. NAM/GFS/LOCAL WRF ARW FCST SNGS ALSO INDICATE GENERAL
SUBSIDENCE IN THE MIXED LYR BLO THE INVRN...SO LES AMOUNTS SHOULD BE
RELATIVELY LGT. HI RES MODELS INDICATE THE MORE FOCUSED LLVL CNVGC
WL IMPACT NRN ONTONAGON/SRN HOUGHTON COUNTY. ALTHOUGH TEMPS WL RISE
INTO THE 20S THIS MRNG BEFORE SFC COLD FNT NOW IN MN CLEARS THE CWA
W-E AND NEWBERRY IN THE AFTN...TEMPS WL FALL W-E FOLLOWING THE FROPA
WITH THE ARRIVAL OF THE COLDER H85 TEMPS.
TNGT...COLDER AIR ASSOCIATED WITH DIGGING SHRTWV IN WRN CANADA/
DEEPENING ARCTIC BRANCH IN THE PLAINS IS PROGGED TO STEADILY ADVECT
INTO THE UPR GRT LKS IN STEADY WNW FLOW/H925 WINDS 20-25KTS.
CONSENSUS OF FAVORED MODELS INDICATES H85 TEMPS WL FALL TO ARND -25C
OVER THE WRN CWA AND -18C OVER THE E BY 12Z SUN. ALTHOUGH THIS CHILL
WITH H85/LK WATER TEMP DIFFERENCE OVER 20C WL SUPPORT LES... HIER
RES MODELS ARE INDICATING LO INVRN BASE MAINTAINED BY ONGOING
SUBIDENCE THAT EXTENDS INTO THE MIXED LYR WL HAMPER LES AMOUNTS. SO
A RELATIVELY HI POP/LO QPF SCENARIO SEEMS TO BE IN STORE. THE
ARRIVING CHILL WL ALSO PUSH THE DGZ BLO THE SFC OVER THE WRN CWA...
SO THIS POOR SN GROWTH WL ALSO HAMPER LES AMOUNTS. BUT THE SMALL SN
FLAKE SIZE WL BE EFFICIENT AT REDUCING VSBY...ESPECIALLY AT EXPOSED
LOCATIONS NEAR LK SUP. EXPECT TEMPS OVER THE INTERIOR W HALF...WHERE
THE INCOMING AIRMASS WL BE MODIFIED LEAST BY THE WARMING OF LK
SUP...TO FALL AS LO AS 15 TO 20 BLO ZERO. WITH APRNT TEMPS LIKELY TO
FALL TO -25 TO -35...OPTED TO ISSUE A WIND CHILL ADVY FOR LATE TNGT
THRU SUN MRNG FOR THE INTERIOR W HALF COUNTIES EVEN THOUGH WIND
SPEEDS MAY NOT HOLD AOA THE THRESHOLD OF 10 MPH.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 426 PM EST SAT JAN 4 2014
NAM SHOWS A DEEP 500 MB TROUGH OVER THE CENTRAL U.S. 00Z MON WITH A
STRONG SOUTHERN STREAM SHORTWAVE NEAR CHICAGO 00Z MON. THE 500 MB
TROUGH MOVES EAST SUN NIGHT WITH THE TROUGH AXIS PUSHING ACROSS THE
CWA ON MON BEFORE THE TROUGH AND UPPER LEVEL LOWS PULL NORTHEAST ON
WED. WHAT THIS WILL MEAN IS VERY COLD AIR MOVING ACROSS THE AREA.
12Z NAM SEEMS TO BE FURTHER NORTHWEST WITH THE TRACK OF THE SFC LOW
FROM WHAT THE ECMWF HAS FOR SUNDAY NIGHT INTO MON. GFS AND ECMWF
SHOW SOME 850-500 MB Q-VECTOR CONVERGENCE SUN NIGHT AND ARE ALSO
FURTHER EAST WITH THE SFC LOW TRACK THAN THE NAM IS. SFC LOW 00Z MON
WITH ECMWF AND GFS IS OVER CENTRAL OHIO WHILE NAM IS OVER WESTERN
OHIO AND AT 06Z MON SFC LOW OFF THE ECMWF AND GFS IS NEAR BUFFALO
NEW YORK WHILE NAM HAS IT NEAR KITCHENER ONTARIO. WILL GO WITH THE
FARTHER EAST TRACK WHICH WILL NOT MEAN MUCH EXCEPT THAT THE SYSTEM
SNOW WILL STAY OUT OF THE AREA AND LAKE EFFECT SNOW SHOWERS WILL BE
THE RULE INSTEAD FOR THIS FORECAST PERIOD WITH ACCUMULATIONS IN THE
NORTHWEST WIND AFFECTED SNOW BELTS. MAIN STORY WILL BE THE COLD
TEMPERATURES AND THE WIND SPEEDS. WIND SPEEDS WILL STAY UP SUN NIGHT
THROUGH TUE NIGHT WITH COLD TEMPERATURES. WIND CHILL VALUES WILL
FALL TO AS LOW AS -50F AND WILL GO WITH WIND CHILL WARNINGS FOR MOST
OF THE AREA. IF WINDS ARE LESS THAN FORECASTED...COULD GET COLDER
AND IF WINDS STAY UP...LOW TEMPERATURES WOULD BE WARMER. EITHER
WAY...WIND CHILL VALUES LOOK TO BE IN THE WARNING CRITERIA AND WILL
GO WITH WIND CHILL WARNINGS. DID NOT MAKE TOO MANY CHANGES TO THE
GOING FORECAST FOR TEMPERATURES EXCEPT FOR A FEW MINOR TWEAKS HERE
AND THERE AND DID NOT MAKE TOO MANY CHANGES TO THE POPS EITHER.
IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH 12Z WED
OVER THE U.S. WITH COLD AIR CONTINUING TO MOVE ACROSS THE AREA...BUT
SOME MODIFICATION HAS ALREADY TAKEN PLACE AS THE POLAR VORTEX AND
EXTREME COLD AIR WILL HAVE MOVED OFF TO THE NORTHEAST BY THAT TIME.
NOT MUCH CHANGES FOR 12Z THU FOR THE UPPER PATTERN. A DEEPENING
TROUGH MOVES INTO THE ROCKIES 12Z FRI WHICH MOVES INTO THE UPPER
GREAT LAKES 12Z SAT WITH WARMER AIR MOVING INTO THE AREA FRI INTO
SAT. TEMPERATURES WILL ACTUALLY GO ABOVE NORMAL FOR FRI INTO
SATURDAY. WILL GO DRY FOR THU NIGHT AND FRIDAY AS WINDS ARE
SOUTHWEST AT THAT TIME AND PUSH THE LAKE EFFECT TO THE NORTH OF THE
AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1246 PM EST SAT JAN 4 2014
WITH INCREASINGLY COLDER AIR FLOWING INTO THE UPPER LAKES...LAKE
EFFECT SNOW SHOWERS WILL BE THE RULE OFF LAKE SUPERIOR IN W TO NW
FLOW. KIWD WILL BE NEAR THE SRN EDGE OF THE LAKE EFFECT SNOW
SHOWERS. IN GENERAL...MVFR CONDITIONS SHOULD PREVAIL THRU THE FCST
PERIOD. HOWEVER...EXPECT SOME PERIODS OF IFR FOR THE NEXT FEW HRS
BEFORE SUBSIDENCE/DRYING IN THE WAKE OF THE COLD FRONT THAT PASSED
EARLIER TODAY BECOME MORE DOMINANT. AT KCMX...PERSISTENT LAKE EFFECT
SNOW SHOWERS SHOULD LEAD TO PREVAILING IFR CONDITIONS. HOWEVER...
THERE WILL BE PERIODS OF LIFR FOR MUCH OF THE AFTN. AS AIR MASS
BECOMES EXTREMELY COLD...SNOWFLAKES WILL BECOME SMALL...LEADING TO A
TREND FOR INCREASINGLY LOWER VIS WITH TIME SUN/MON. AS A
RESULT...THERE MAY BE AN EXTENDED PERIOD OF LIFR VIS DEVELOPING AT
SOME POINT SUN AT KCMX. AT KSAW...OCNL -SHSN JUST BEHIND PASSING
COLD FRONT WILL LEAD TO MVFR/OCNL IFR FOR THE NEXT COUPLE OF HRS.
THEN...THERE SHOULD BE ENOUGH DRYING/SUBSIDENCE TO CAUSE CONDITIONS
TO IMPROVE TO VFR LATER TODAY/TONIGHT IN THE PRESENCE OF A DOWNSLOPE
WNW FLOW. MVFR CONDITIONS MAY RETURN SUN MORNING AS WINDS VEER A
LITTLE MORE NORTHERLY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 505 AM EST SAT JAN 4 2014
SW GALES AHEAD OF AN APPROACHING COLD FRONT OVER EASTERN LAKE
SUPERIOR WILL DIMINISH THIS MORNING WITH THE ARRIVAL OF A WEAKER
PRES GRADIENT. IT NOW APPEARS THE NW WINDS BEHIND THE FRONT WL NOT
BE AS STRONG AS EARLIER ANTICIPATED AND NOT REACH GALE THRESHOLDS
EXCEPT PERHAPS OVER THE E PART OF THE LAKE THIS AFTERNOON. SO OPTED
TO CANX THE GOING GALE WARNING FOR ALL BUT THAT AREA. DID SHORTERN
THE WARNING FOR THE E THIS EVENING SINCE THE MARGINAL GALES THERE
WILL DIMINISH BY THEN. EVEN THOUGH THE NW WINDS WILL BE UP TO ONLY
25-30 KTS INSTEAD OF 35 KTS THRU TONIGHT...THE ARRIVAL OF BITTERLY
COLD ARCTIC AIR/SUFFICIENTLY HI WAVES WILL RESULT IN WIDESPREAD
HEAVY FREEZING SPRAY...ESPECIALLY THIS AFTERNOON AND TONIGHT.
WEST TO NORTHWEST WINDS OF 15 TO 25 KNOTS WILL CONTINUE FROM SUNDAY
INTO MONDAY MORNING. THE TIGHTENING PRESSURE GRADIENT BETWEEN LOW
PRESSURE OVER THE NEW ENGLAND STATES AND INCOMING HIGH PRESSURE FROM
THE NORTHERN PLAINS WILL BRING NORTHWEST GALES TO 40 KNOTS TO MAINLY
CENTRAL AND EASTERN LAKE SUPERIOR MONDAY AFTERNOON INTO TUESDAY
EVENING. HIGH PRESSURE WILL RETURN WEDNESDAY INTO THURSDAY AND BRING
WINDS DOWN BELOW 20 KNOTS. APPROACHING LOW PRESSURE WILL BRING
SOUTHERLY WINDS 15 TO 25 KNOTS TO LAKE SUPERIOR FOR FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WARNING FROM 7 PM EST /6 PM CST/ SUNDAY TO 11 AM EST
/10 AM CST/ TUESDAY FOR MIZ001>005-009>013-084.
WIND CHILL ADVISORY FROM MIDNIGHT EST /11 PM CST/ TONIGHT TO 7
PM EST /6 PM CST/ SUNDAY FOR MIZ002-009-010-084.
WIND CHILL WARNING FROM 7 PM MONDAY TO 11 AM EST TUESDAY FOR
MIZ006-007-014-085.
WIND CHILL ADVISORY FROM 7 PM SUNDAY TO 1 PM EST MONDAY FOR
MIZ006-007-014-085.
WIND CHILL ADVISORY FROM MIDNIGHT EST /11 PM CST/ TONIGHT TO
NOON EST /11 AM CST/ SUNDAY FOR MIZ004-005-011.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 7 AM EST
WEDNESDAY FOR LSZ267.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ266-267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY
FOR LSZ162-263>266.
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST MONDAY FOR
LSZ243>245-248>251.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SHORT TERM...KC
LONG TERM...07
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1227 PM EST SAT JAN 4 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 330 AM EST SAT JAN 4 2014
A COLD FRONT WILL DROP DOWN INTO THE AREA TODAY AND SLOWLY MOVE
THROUGH THE AREA THROUGH THE DAY ON SUNDAY. SOME LIGHT SNOW WILL
DEVELOP ALONG THIS FRONT...AND WILL BECOME MORE WIDESPREAD THIS
EVENING AS IT PRESSES SOUTHEAST. ADDITIONAL SNOW WILL DEVELOP AND
MOVE ALONG THIS FRONT WITH A WAVE OF LOW PRESSURE ON SUNDAY AND
SUNDAY EVENING.
MUCH COLDER AIR WILL THEN OVERSPREAD THE AREA LATE SUNDAY AND INTO
MONDAY. TEMPERATURES WILL MAINLY FALL SUNDAY NIGHT AND MONDAY.
STRONG WINDS WILL COMBINE WITH THE COLD TO PRODUCE WIND CHILLS WELL
BELOW ZERO. THE AREA HAS NOT SEEN THE AIR THIS COLD AT LEAST FOR A
FEW YEARS. TEMPERATURES WILL MODERATE LATE NEXT WEEK.
&&
.UPDATE...
ISSUED AT 1051 AM EST SAT JAN 4 2014
I AM SERIOUSLY CONSIDERING EXPANDING THE WINTER STORM WARNING AT
LEAST ONE ROW OF COUNTIES FARTHER NORTH WITH THE AFTERNOON
FORECAST UPDATE. SEEMS TO ME THE MODEL CONUS IS CONVERGING ON A
SOLUTION BETWEEN THE NAM AND THE GFS PUTTING THE HEAVIER
PRECIPITATION TONIGHT NEAR AND JUST SOUTH OF A LINE FROM NEAR
GRAND HAVEN TO GRAND RAPIDS TO ALMA. THE RAP 13Z AND NAM12 SHOW A
BAND OF .2 TO .4 QPF BY 12Z SUNDAY FROM ALONG THAT LINE...AS DOES
THE 12Z GFS. THIS SNOW BAND IS FGEN RELATED AND IS A REFLECTION
OF WHERE THE FRONT IS BETWEEN 850 AND 700 MB. WHICH TO ME
SUGGESTS HEAVY SNOW IS MORE THAN LIKELY ONE ROW OF COUNTIES
FATHER NORTH IN THE SHORT TERM. FOR NOW THOUGH I PLAN ON LEAVING
HEADLINES AS THEY ARE SINCE THE GFS IS STILL WELL SOUTH OF THE NAM
&&
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 330 AM EST SAT JAN 4 2014
WE WILL BE UPGRADING TO A WARNING FOR MOST OF THE AREA THAT WAS IN
THE WATCH. THE NW EDGE OF THE WATCH WILL BE TRANSITIONED TO AN
ADVISORY ALONG WITH SOME ADDITIONAL COUNTIES. THE MAIN PERIOD OF
CONCERN IN THE SHORT TERM IS FROM THIS EVENING INTO SUNDAY EVENING
WITH THE SNOW. THE WIND CHILL WATCH WILL BE MAINTAINED FOR THE TIME
BEING.
WE ARE EXPECTING SNOW TO BEGIN TO DEVELOP THIS MORNING ACROSS THE NW
CORNER OF THE CWFA. THE SNOW WILL START OUT RATHER LIGHT AS
THE AREA ALONG THE FRONT LIGHTS UP A BIT LIKELY AHEAD OF THE SHORT
WAVE THAT WILL APPROACH THE AREA FROM THE DAKOTAS. ALSO...THERE
LOOKS TO BE SOME LAKE ENHANCEMENT. DELTA T/S ARE NOT IN THE
TEENS...BUT THEY WILL BE ALMOST 10C WHICH IS USUALLY SUFFICIENT
ENOUGH FOR AT LEAST A SMALL BOOST FROM THE LAKE. THERE WILL ALSO BE
SOME ADDED CONVERGENCE FROM THE LAKE INFLUENCE THAT WILL ALSO HELP.
THE LIGHT SNOW WILL EXPAND A BIT THIS AFTERNOON AND THEN THIS
EVENING INTO THE CENTRAL PORTIONS OF THE AREA. THE AFOREMENTIONED
SHORT WAVE WILL INITIALLY ZIP TO THE NE OF THE CWFA AFTER 18Z TODAY.
WE WILL THEN SEE THE RRQ MOVE OVER THE AREA VIA A 140 KT JET STREAK
SOUTH OF JAMES BAY. THIS WILL ACT ON THE FRONT AND THE LIMITED LAKE
CONTRIBUTION TO SPREAD THE SNOW INLAND A BIT MORE. THE FRONT SHOULD
MOVE SE OF KGRR AFTER 00Z AND FOCUS THE BETTER SNOW DOWN THERE.
LIGHT SNOW WILL CONTINUE THEN ACROSS THE SE HALF OF THE CWFA LATER
TONIGHT AND EARLY SUN. WE LOSE THE UPPER JET DYNAMICS...BUT WE
CONTINUE WITH A GRADUAL ISENTROPIC ASCENT/OVERRUNNING SITUATION NW
OF THE FRONT THAT THEN STALLS OUT TO OUR SE. THIS FRONT WILL BE
AWAITING THE NEXT UPPER WAVE EXPECTED TO DIVE INTO THE SRN PLAINS
AROUND 12Z SUN BEFORE LIFTING NE TOWARD THE LOWER GREAT LAKES. THIS
WAVE WILL BRING ANOTHER ROUND OF SNOW ACROSS THE WARNING AREA SUN
AFTERNOON AND EVENING.
ONCE THE SYSTEM SNOW MOVES OUT SUN EVENING...WE WILL SEE NW FLOW
LAKE EFFECT BECOME ESTABLISHED WITH THE EXTREMELY COLD ARCTIC AIR
THAT WILL SPREAD ACROSS THE AREA.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 330 AM EST SAT JAN 4 2014
THE MAIN EMPHASIS IN THE LONG TERM CONTINUES TO BE ON THE BRUTALLY
COLD AIR MASS SWEEPING ACROSS MICHIGAN ON MONDAY AND TUESDAY. WIND
CHILLS ARE EXPECTED TO BE AROUND -25 OVER MOST OF THE AREA HOWEVER
VALUES ALONG THE I-94 CORRIDOR EAST OF KALAMAZOO MAY REACH AS LOW AS
-35 OR -40 MONDAY NIGHT WHERE A LK MI INFLUENCE PROBABLY WILL NOT BE
PRESENT AS SFC WINDS BECOME SOUTHWEST.
IN ADDITION TO THE SEVERE WIND CHILL READINGS... LAKE EFFECT SNOW
AND BLOWING SNOW WILL IMPACT THE AREA MONDAY AND TUESDAY.
ACCUMULATIONS WILL BE HELD DOWN DUE TO SMALL CRYSTAL SIZE BUT
VISIBILITIES SHOULD STILL BE GREATLY REDUCED AND ROADS WILL BE ICY
SINCE ROAD CHEMICALS WILL BE INEFFECTIVE WITH THE VERY COLD TEMPS.
THE REALLY COLD SFC AIR OF -10 TO -15 CURLING AROUND THE BOTTOM OF
LK MI INTO THE I-94 CORRIDOR REGION WILL LIKELY RESULT IN A NICE LOW
LEVEL CONVERGENCE/FGEN ZONE FOR THE LAKE EFFECT SNOW. A LENGTHY
EASTWARD/INLAND EXTENSION OF LAKE EFFECT SHOULD SET UP NEAR OR JUST
SOUTH OF THE I-96 CORRIDOR MONDAY NIGHT AND TUESDAY.
THE CORE OF THE COLDEST AIR LIFTS OUT TUESDAY NIGHT AND A MODERATING
TREND IN TEMPS IS EXPECTED FOR MID TO LATE WEEK. HIGHS BY FRIDAY
SHOULD BE UP NEAR 30. HOWEVER MORE LIGHT SNOW IS POSSIBLE WEDNESDAY
AND THURSDAY DUE TO WEAK WARM ADVECTION/ISENTROPIC LIFT PATTERN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1227 PM EST SAT JAN 4 2014
A COLD FRONT WAS CROSSING EASTERN WISCONSIN EARLY THIS AFTERNOON.
AN AREA OF MOSTLY LIGHT SNOW WAS DEVELOPING UPSTREAM...AROUND MKE
AND CHI. THIS WILL BE SPREADING INTO THE TAF SITES THROUGH THE
AFTERNOON. EXPECT CONDITIONS TO DETERIORATE TO A MIX OF MVFR AND IFR
ONCE THIS SNOW ARRIVES. CONDITIONS SHOULD TREND LOWER TO MOSTLY
IFR INTO THE EARLY EVENING AS MIXING DECREASES ALLOWING CEILINGS
TO LOWER FURTHER. ANOTHER SURGE OF STEADIER SNOWS ARE EXPECTED BY
MID SUNDAY MORNING RESULTING IN WIDESPREAD IFR AND LIFR.
SOUTHWEST WINDS WILL GRADUALLY DIMINISH THROUGH THE AFTERNOON AS
THE FRONT SAGS IN. GUSTS OF 20-25 KTS SHOULD BE EXITING THE AREA
BY ABOUT 20Z. THEN DROPPING OFF EVEN FURTHER BY MID EVENING TO 8
KTS OR LESS. THE LIGHTER WINDS WILL SHIFT TO THE NORTH OVERNIGHT.
&&
.MARINE...
ISSUED AT 1051 AM EST SAT JAN 4 2014
I HAVE DOWNGRADED THE GALE WARNING TO A SMALL CRAFT ADVISORY SINCE
WINDS ARE DIMINISHING AS I WRITE THIS. WE MAY NEED A GALE WARNING
AND FREEZING SPRAY WARNING SUNDAY NIGHT INTO MONDAY BUT WILL NOT
ISSUE THAT JUST YET.
&&
.HYDROLOGY...
ISSUED AT 315 PM EST FRI JAN 3 2014
A FLOOD ADVISORY IS IN EFFECT FOR THE FLAT RIVER AT SMYRNA. A
SUSPECTED ICE JAM UPSTREAM HAS CAUSED A SHARP RISE FOLLOWED BY A
SHARP DECLINE AT THE SMYRNA RIVER GAUGE. ICE JAMS CAN CAUSE RAPID
FLUCTUATIONS IN RIVER LEVELS.
RIVERS WILL CONTINUE GAINING ICE COVERAGE AND THICKNESS FOR THE
FORESEEABLE FUTURE. THOSE RIVERS THAT ICE OVER COMPLETELY WILL HAVE
A MINIMAL ICE JAM THREAT. RIVERS WITH JAGGED ICE BUILDUP ARE IN
DANGER OF EXPERIENCING JAMMING AND RAPID FLUCTUATIONS. 6 OR MORE
INCHES OF SNOW IS EXPECTED FOR SOUTHERN AND SOUTHEAST LOWER MICHIGAN
SATURDAY NIGHT THROUGH SUNDAY EVENING. A BLAST OF EXTREME COLD AIR
FOLLOWS THE SNOW ON SUNDAY NIGHT.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 1 AM EST
MONDAY FOR MIZ051-052-056>058-064.
WIND CHILL WATCH FROM LATE SUNDAY NIGHT THROUGH TUESDAY
AFTERNOON FOR MIZ037>040-043>046-050>052-056>059-064>067-
071>074.
WINTER STORM WARNING FROM 7 PM THIS EVENING TO 1 AM EST MONDAY
FOR MIZ059-065>067-071>074.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
LMZ844>849.
&&
$$
UPDATE...WDM
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...MEADE
AVIATION...JK
HYDROLOGY...EBW
MARINE...WDM
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1156 AM CST Sat Jan 4 2014
.UPDATE...
Issued at 1148 AM CST SAT JAN 4 2014
Based on a northern band of snow developing across northern MO this
afternoon have added one more row of counties to the northern portion
of the winter Weather Advisory. Have also broken off the far southern
counties with a later start time for snow.
UPDATE Issued at 1030 AM CST SAT JAN 4 2014
Have delayed the southward development of snow into the CWA. Current
band of light snow from southeast NE across southern IA tied to the
passing of the northern shortwave with elevated frontogenesis. 12z
NAM and RAP keep QPF north of Highway 36 through 21z and based on
current radar trends and expectations seems reasonable to delay snow
development for most of the CWA. 12z NAM has also jumped onto the
previous runs of the GFS in developing two separate bands of
snow...one across northern MO associated with the elevated
frontogenesis and a second and likely heavier band tied to the chunk
of energy and speed max diving southeast into the Central Rockies.
This energy is expected to spread into KS/OK this evening with a
significant PV anomaly digging into the base of the deepening upper
trough.
Have also increased snow amounts across northern MO due to this first
band which is expected to from by mid afternoon. Have also kept
categorical PoPs longer over the southeastern CWA through the night.
Could see some light rain across the far southern counties this
afternoon with temperatures well above freezing. Shouldn`t be much
nor last long as the cold front will push through by early evening.
&&
.SHORT TERM...(Today through Sunday Afternoon)
Issued at 335 AM CST SAT JAN 4 2014
In the short term, the main focus will be snow chances and amounts
for this afternoon through Sunday morning as a wintry system pushes
across the region. Two separate systems will result in snow chances
around the forecast area; 1) a southeastward moving cold front that
is currently located from central NE through north central IA, and
2) a shortwave trough lifting northeastward out of the southern
Plains. The primary snow-producer for our area will be the former,
especially along the elevated ~700 mb front.
Very light, patchy snow showers have developed behind the surface
cold front in portions of eastern NE and northern IA early this
morning, and will transition southward as the day progresses. As the
front moves south, it will encounter better moisture especially
below ~600-650 mb, helping light snow to fill in and increase in
intensity. Precipitation amounts will increase from northwest to
southeast where the better moisture resides, but still may not be
overly impressive with most of the lift/forcing centered along and
above the 700 mb front, through an increasingly dry layer. However,
quickly falling temperatures will help saturated portions of the
sounding to fall to around or below the -10 C mark, increasing snow
to liquid ratios to around 15:1 or greater by this evening into the
overnight hours. The greatest snow accumulations are expected from
00z to 09z Sunday, but light snow could stretch from mid afternoon
through mid-morning Sunday. Total amounts will range from less than
an inch in far northwest MO, to around 2 inches in the KC metro, to
4 inches or greater in our far southeast. Have issued a winter
weather advisory for areas along and southeast of a line from
Leavenworth county KS to Adair county MO, generally for 2-4 inches
of snow. Some enhancement of snow totals may occur in the far
southeast where the second (southern) system may brush our CWA this
evening ahead of the elevated cold front, possibly allowing for some
4-5 inch totals along our southeastern border.
Temperatures today may not rise much this morning under increasing
clouds, but won`t need to go far to make it into the middle to upper
30s across much of the region. The surface front will push into
northwest MO by late morning and should clear the forecast area by 6
PM, with falling temperatures trailing not far behind. Very minimal
clearing is expected tonight except in far northwest MO, but cold
air advection should knock temperatures into the single digits or
lower teens for most of the CWA by early Sunday morning, and little
to no diurnal rise is expected for Sunday.
.LONG TERM...(Sunday Night through Friday)
Issued at 335 AM CST SAT JAN 4 2014
The primary concern for the mid and long range forecast periods will
be the arrival of the arctic airmass Sunday night into Monday
morning. H85 temperatures of -25C to -30C will overspread the
forecast area. Early morning low temperatures are expected to fall
to the -10F to -13F range north to around -6F south. In addition,
breezy northwesterly winds of 10 to 20 mph will result in
dangerously cold wind chill readings, with values between -25F to
-35F. A wind chill warning will likely be required for Sunday night
into midday Monday for the entire forecast area. Bitterly cold
temperatures will continue during the day on Monday, with highs only
reaching the -5F to 5F above zero range. One more dangerously cold
night is expected Monday night into Tuesday morning, with lows
between -10F to 0F. Wind speeds are expected to be lower compared to
the previous night, resulting in wind chill values slightly less
extreme than the previous night.
Temperatures will gradually moderate throughout the remainder of the
work week, with readings finally reaching near normal levels by
Friday. Westerly to southwesterly flow aloft will prevail during
this period, with several weak upper disturbances projected to move
near/across the area. A chance of light snow will be possible
Wednesday into Wednesday night, with a chance of light snow or light
rain possible Friday into Friday night. A good amount of uncertainty
exists with both scenarios with timing, intensity, and track of each
upper disturbance. Overall, current model solutions suggest that
notable amounts of precipitation are not expected with either
system.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1148 AM CST SAT JAN 4 2014
Based on latest short term models and supported by current radar
trends have slowed down the arrival of snow into the terminals. Have
also attempted to pick out a 4 hour wind with the best potential for
heavier snow, lower visibilities and ceilings. Prefer to keep
ceilings in the MVFR category.
Expect a band of snow to develop across northern MO this afternoon
and gradually shift/spread southward reaching the MO river around 00z
or shortly thereafter. A larger area of snow is forecast to form this
evening across west central and central MO and east central KS as an
upper level system moves out of CO into KS and OK. This area of snow
will be widespread and persist through the night with snow amounts
increasing from west to east.
Expect 1 to 2 inches at KSTJ and 2 to 3 inches at KMCI/KMKC.
Cold front will be moving through the KC terminals right at the start
of the forecast with northerly winds increasing and becoming gusty a
2-3 hours after frontal passage. Winds will remain strong through the
rest of the forecast with a gradual decrease Sunday morning.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY from 3 PM this afternoon to 9 AM CST
Sunday FOR KSZ025-103>105.
WINTER WEATHER ADVISORY from 6 PM this evening to 9 AM CST
Sunday FOR KSZ057-060.
MO...WINTER WEATHER ADVISORY from 3 PM this afternoon to 9 AM CST
Sunday FOR MOZ013>017-020>025-028>033-037>040.
WINTER WEATHER ADVISORY from 6 PM this evening to 9 AM CST
Sunday FOR MOZ043>046-053-054.
&&
$$
UPDATE...MJ
SHORT TERM...Laflin
LONG TERM...Blair
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1044 AM CST Sat Jan 4 2014
.UPDATE...
Issued at 1030 AM CST SAT JAN 4 2014
Have delayed the southward development of snow into the CWA. Current
band of light snow from southeast NE across southern IA tied to the
passing of the northern shortwave with elevated frontogenesis. 12z
NAM and RAP keep QPF north of Highway 36 through 21z and based on
current radar trends and expectations seems reasonable to delay snow
development for most of the CWA. 12z NAM has also jumped onto the
previous runs of the GFS in developing two separate bands of
snow...one across northern MO associated with the elevated
frontogenesis and a second and likely heavier band tied to the chunk
of energy and speed max diving southeast into the Central Rockies.
This energy is expected to spread into KS/OK this evening with a
significant PV anomaly digging into the base of the deepening upper
trough.
Have also increased snow amounts across northern MO due to this first
band which is expected to from by mid afternoon. Have also kept
categorical PoPs longer over the southeastern CWA through the night.
Could see some light rain across the far southern counties this
afternoon with temperatures well above freezing. Shouldn`t be much
nor last long as the cold front will push through by early evening.
&&
.SHORT TERM...(Today through Sunday Afternoon)
Issued at 335 AM CST SAT JAN 4 2014
In the short term, the main focus will be snow chances and amounts
for this afternoon through Sunday morning as a wintry system pushes
across the region. Two separate systems will result in snow chances
around the forecast area; 1) a southeastward moving cold front that
is currently located from central NE through north central IA, and
2) a shortwave trough lifting northeastward out of the southern
Plains. The primary snow-producer for our area will be the former,
especially along the elevated ~700 mb front.
Very light, patchy snow showers have developed behind the surface
cold front in portions of eastern NE and northern IA early this
morning, and will transition southward as the day progresses. As the
front moves south, it will encounter better moisture especially
below ~600-650 mb, helping light snow to fill in and increase in
intensity. Precipitation amounts will increase from northwest to
southeast where the better moisture resides, but still may not be
overly impressive with most of the lift/forcing centered along and
above the 700 mb front, through an increasingly dry layer. However,
quickly falling temperatures will help saturated portions of the
sounding to fall to around or below the -10 C mark, increasing snow
to liquid ratios to around 15:1 or greater by this evening into the
overnight hours. The greatest snow accumulations are expected from
00z to 09z Sunday, but light snow could stretch from mid afternoon
through mid-morning Sunday. Total amounts will range from less than
an inch in far northwest MO, to around 2 inches in the KC metro, to
4 inches or greater in our far southeast. Have issued a winter
weather advisory for areas along and southeast of a line from
Leavenworth county KS to Adair county MO, generally for 2-4 inches
of snow. Some enhancement of snow totals may occur in the far
southeast where the second (southern) system may brush our CWA this
evening ahead of the elevated cold front, possibly allowing for some
4-5 inch totals along our southeastern border.
Temperatures today may not rise much this morning under increasing
clouds, but won`t need to go far to make it into the middle to upper
30s across much of the region. The surface front will push into
northwest MO by late morning and should clear the forecast area by 6
PM, with falling temperatures trailing not far behind. Very minimal
clearing is expected tonight except in far northwest MO, but cold
air advection should knock temperatures into the single digits or
lower teens for most of the CWA by early Sunday morning, and little
to no diurnal rise is expected for Sunday.
.LONG TERM...(Sunday Night through Friday)
Issued at 335 AM CST SAT JAN 4 2014
The primary concern for the mid and long range forecast periods will
be the arrival of the arctic airmass Sunday night into Monday
morning. H85 temperatures of -25C to -30C will overspread the
forecast area. Early morning low temperatures are expected to fall
to the -10F to -13F range north to around -6F south. In addition,
breezy northwesterly winds of 10 to 20 mph will result in
dangerously cold wind chill readings, with values between -25F to
-35F. A wind chill warning will likely be required for Sunday night
into midday Monday for the entire forecast area. Bitterly cold
temperatures will continue during the day on Monday, with highs only
reaching the -5F to 5F above zero range. One more dangerously cold
night is expected Monday night into Tuesday morning, with lows
between -10F to 0F. Wind speeds are expected to be lower compared to
the previous night, resulting in wind chill values slightly less
extreme than the previous night.
Temperatures will gradually moderate throughout the remainder of the
work week, with readings finally reaching near normal levels by
Friday. Westerly to southwesterly flow aloft will prevail during
this period, with several weak upper disturbances projected to move
near/across the area. A chance of light snow will be possible
Wednesday into Wednesday night, with a chance of light snow or light
rain possible Friday into Friday night. A good amount of uncertainty
exists with both scenarios with timing, intensity, and track of each
upper disturbance. Overall, current model solutions suggest that
notable amounts of precipitation are not expected with either
system.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday Morning)
Issued at 537 AM CST SAT JAN 4 2014
VFR conditions and mainly light southwest winds will be replaced by
MVFR to possibly IFR stratus and breezy north winds during the early
to mid afternoon hours behind a southeastward moving cold front. In
addition, light to moderate snow will develop during the afternoon
and will spread southeast across the area during the late afternoon
and evening hours. Reduced visibilities and slightly lower ceilings
are possible while snow is falling. Snow will taper off from
northwest to southeast tonight into Sunday morning, ending between
09z and 15z.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY from 3 PM this afternoon to 9 AM CST
Sunday FOR KSZ057-060-103>105.
MO...WINTER WEATHER ADVISORY from 3 PM this afternoon to 9 AM CST
Sunday FOR MOZ017-021>025-028>033-037>040-043>046-053-054.
&&
$$
UPDATE...MJ
SHORT TERM...Laflin
LONG TERM...Blair
AVIATION...Laflin
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1145 AM CST SAT JAN 4 2014
.UPDATE...AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 1009 AM CST SAT JAN 4 2014/
MAINLY CLEAR SKIES ACROSS THE MIDSOUTH...WILL ALLOW FOR HIGH
TEMPS TO BE A FEW DEGREES WARMER WITH MORE SUN THROUGH THE REST OF
THE MORNING AND INTO THE EARLY AFTERNOON BEFORE CLOUDS START TO
DEVELOP.SOUTHERLY FLOW WILL HELP WITH THIS AS WELL. HAVE BUMPED
AFTERNOON HIGHS ACCORDINGLY...AND DEWPTS WITH LATEST RUC DATA AS
EACH SHOULD CLIMB STEADILY AND LIKELY A BIT FASTER THAN PREVIOUS
FORECAST. -ABS
PREV DISCUSSION... /ISSUED 528 AM CST SAT JAN 4 2014/
UPDATE...
UPDATED FOR 12Z AVIATION DISCUSSION.
PREV DISCUSSION... /ISSUED 450 AM CST SAT JAN 4 2014/
DISCUSSION...
CURRENTLY...TEMPERATURES ARE HOLDING STEADY OR RISING ACROSS MOST
AREA DUE TO AN INCREASING SOUTHERLY FLOW AHEAD OF THE DEVELOPING
SYSTEM OVER THE SOUTHERN PLAINS. SOME AREAS OF NE MS ARE STILL
DROPPING SINCE WINDS THERE ARE STILL LIGHT DUE TO THE PROXIMITY OF
THE RETREATING SURFACE HIGH. SKIES ARE MOSTLY CLEAR WITH JUST A
FEW HIGH CLOUDS ACROSS THE NORTH.
TODAY...TAKE ADVANTAGE. MILDER SOUTHERLY FLOW ACROSS THE REGION
AND A GOOD DEAL OF SUNSHINE...ESPECIALLY THIS MORNING...WILL ALLOW
TEMPS TO CLIMB CLOSE TO NORMAL. MID AND HIGH CLOUDS WILL BE ON THE
INCREASE THIS AFTERNOON AS LOW PRESSURE WILL STARTS TO ORGANIZE
NEAR THE RED RIVER VALLEY ALONG THE DEVELOPING ARCTIC FRONT. THE
POLAR VORTEX WILL CONTINUE DROPPING SOUTH WITH VERY COLD AIR PUSHING
INTO THE NORTHERN U.S.
TONIGHT...LOW PRESSURE WILL MOVE NORTHEAST ALONG THE STRENGTHENING
ARCTIC FRONT AND MOVE INTO EASTERN ARKANSAS LATE TONIGHT. RAIN WILL
DEVELOP AND SPREAD OVER THE REGION...ESPECIALLY AFTER MIDNIGHT.
TOWARD SUNRISE RAIN MAY START TO CHANGE TO SNOW ACROSS NE AR AS
COLD AIR BEGINS TO SEEP IN. LOWS TEMPS WILL BE QUITE A BIT MILDER
THANKS TO THE SOUTHERLY FLOW...IN THE 30S TO AROUND 40.
SUNDAY...BIG CHANGE IN STORE. LOW PRESSURE WILL MOVE TO THE TN
RIVER BY 18Z AND A POTENT SHORTWAVE WILL RAPIDLY KICK THE ARCTIC
FRONT EAST IN THE WAKE OF THE SURFACE LOW. TEMPS WILL COOL
RAPIDLY INTO THE 20S AS GUSTY NORTHWEST WINDS DEVELOP. RAIN WILL
CHANGE QUICKLY TO SNOW. THERE COULD BE A BRIEF PERIOD OF SLEET AS
THE COLD AIR AT THE SURFACE RUNS AHEAD OF THE COLD AIR ALOFT
LEAVING A WEAK WARM LAYER AROUND 5KFT. THIS WILL NOT LAST LONG
THOUGH. RIGHT NOW IT LOOKS LIKE THE ARCTIC FRONT WILL BE MOVING
INTO THE NW CORNER OF THE MIDSOUTH JUST BEFORE 12Z...MS RIVER
AROUND 18Z AND NE MS BY MID AFTERNOON. MODEL SOUNDINGS SHOW
FAIRLY DEEP MOISTURE FOR A FEW HOURS BEHIND THE FRONT. THIS
COMBINED WITH A POTENT MID LEVEL SHORTWAVE WILL PRODUCE
ACCUMULATING SNOW...ESPECIALLY ACROSS THE NORTHERN TIER WHERE THE
WATCH IS IN EFFECT. AN INCH OR TWO LOOKS POSSIBLE IN MEMPHIS WITH
LESSER AMOUNTS TO THE SOUTH. THE SNOW COMBINED WITH THE RAPIDLY
FALLING TEMPS AND WIND WILL RESULT IN A FLASH FREEZE WITH ROADWAYS
AND BRIDGES BECOMING SLICK QUICKLY.
SUNDAY NIGHT...LINGERING SNOW WILL TAPER OFF ACROSS EASTERN
SECTIONS DURING THE EVENING THOUGH FLURRIES WILL CONTINUE AS VERY
COLD AIR ADVECTS IN ON GUSTY NW WINDS. THE POLAR VORTEX WILL MOVE
INTO THE GREAT LAKES WHILE THE COLDEST AIR SINCE FEB 1996 SETTLES
OVER THE MIDSOUTH. 850MB TEMPS OF -20C OR LOWER AND 1000-500MB
THICKNESS VALUES APPROACHING 500DM. DESPITE THE WIND AND SOME
CLOUDS TEMPS WILL FALL INTO THE SINGLE DIGITS ACROSS MUCH OF THE
AREA BY MONDAY MORNING. WIND CHILLS WILL DROP TO BELOW ZERO ACROSS
THE ENTIRE AREA AND BELOW MINUS 10 NORTH OF I-40. NOW IS THE TIME
TO THINK ABOUT THOSE PIPES.
MONDAY THROUGH TUESDAY NIGHT...VERY COLD. MONDAY WILL BE THE
FIRST DAY MEMPHIS DOES NOT GET OUT OF THE TEENS SINCE FEB 1996.
PLACES UP NORTH WILL PROBABLY STAY IN THE SINGLE DIGITS. MONDAY
NIGHT WILL BE ANOTHER VERY COLD NIGHT AS SURFACE HIGH PRESSURE
WILL BE CENTERED ON THE MIDSOUTH. ANY SNOW ON THE GROUND WILL ONLY
AID RADIATIONAL COOLING AND HELP DROP TEMPS EVEN FURTHER. LOTS OF
SINGLE DIGITS EXPECTED WITH SOME BELOW ZERO READINGS POSSIBLE. THE
COLDEST AIR STARTS TO RETREAT EAST ON TUESDAY THOUGH TEMPS WILL
STILL BE QUITE COLD...IN THE 20S.
WEDNESDAY THROUGH FRIDAY...OVERRUNNING PATTERN SETS UP OVER THE
RETREATING ARCTIC AIRMASS WITH PRECIP CHANCES INCREASING. A
WINTRY MIX WILL BE POSSIBLE ACROSS NORTHERN AREAS WEDNESDAY
THROUGH THURSDAY MORNING WITH CHANCES FOR RAIN ELSW. ENOUGH
WARMING OCCURS FOR ONLY RAIN BY MID MORNING THURSDAY THROUGH
FRIDAY.
SJM
&&
.AVIATION...18Z TAFS
IMPORTANT CHANGES TO THE PREVIOUS SET OF TAFS INCLUDE THE
INTRODUCTION OF RA/SN TOWARDS THE END OF THE PERIOD AND 5-10 KT
LESS WIND SHEAR. VFR CONDITIONS WILL CONTINUE THROUGH THE FIRST
HALF OF THE TAF PERIOD WITH CIGS DECREASING TO MVFR BY 03Z AT
JBR...5Z AT MEM AND TUP AND...6Z AT MKL. RAIN WILL BEGIN AN HOUR
OR SO AFTER MVFR CIGS MOVE IN AT ALL SITES. THE CHANGEOVER TO SNOW
LOOKS TO BE DELAYED A BIT IN LATEST GUIDANCE. SO WILL KEEP ALL
PRECIPITATION RA THROUGH 14Z AT JBR...15Z AT MEM AND 16Z AT MKL.
IFR CIGS ARE EXPECTED AT JBR...MEM AND MKL BEFORE SUNRISE.
GENERALLY SOUTHERLY WINDS WILL BE SUSTAINED 12-18 KTS AND GUSTS
IN THE 18-26 KT RANGE. DECREASE 10 10-15KT AND LESS GUSTY
OVERNIGHT. OVERNIGHT...WHEN WINDS ARE LIGHTEST AT THE
SURFACE...THE WIND SHEAR THREAT WILL BE GREATEST. WIND SHIFT IS
EXPECTED AT JBR PRIOR TO 18S.
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 49 39 43 10 / 10 60 100 20
MKL 46 38 42 5 / 0 50 100 30
JBR 44 35 35 6 / 10 90 100 20
TUP 48 38 48 9 / 0 30 100 40
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR CLAY-GREENE-LAWRENCE-RANDOLPH.
MO...WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR DUNKLIN-PEMISCOT.
MS...NONE.
TN...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING
FOR CARROLL-DYER-GIBSON-HENRY-LAKE-OBION-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1009 AM CST SAT JAN 4 2014
.UPDATE...
MAINLY CLEAR SKIES ACROSS THE MIDSOUTH...WILL ALLOW FOR HIGH TEMPS
TO BE A FEW DEGREES WARMER WITH MORE SUN THROUGH THE REST OF THE
MORNING AND INTO THE EARLY AFTERNOON BEFORE CLOUDS START TO
DEVELOP.SOUTHERLY FLOW WILL HELP WITH THIS AS WELL. HAVE BUMPED
AFTERNOON HIGHS ACCORDINGLY...AND DEWPTS WITH LATEST RUC DATA AS
EACH SHOULD CLIMB STEADILY AND LIKELY A BIT FASTER THAN
PREVIOUS FORECAST. -ABS
&&
.PREV DISCUSSION... /ISSUED 528 AM CST SAT JAN 4 2014/
UPDATE...
UPDATED FOR 12Z AVIATION DISCUSSION.
PREV DISCUSSION... /ISSUED 450 AM CST SAT JAN 4 2014/
DISCUSSION...
CURRENTLY...TEMPERATURES ARE HOLDING STEADY OR RISING ACROSS MOST
AREA DUE TO AN INCREASING SOUTHERLY FLOW AHEAD OF THE DEVELOPING
SYSTEM OVER THE SOUTHERN PLAINS. SOME AREAS OF NE MS ARE STILL
DROPPING SINCE WINDS THERE ARE STILL LIGHT DUE TO THE PROXIMITY OF
THE RETREATING SURFACE HIGH. SKIES ARE MOSTLY CLEAR WITH JUST A
FEW HIGH CLOUDS ACROSS THE NORTH.
TODAY...TAKE ADVANTAGE. MILDER SOUTHERLY FLOW ACROSS THE REGION
AND A GOOD DEAL OF SUNSHINE...ESPECIALLY THIS MORNING...WILL ALLOW
TEMPS TO CLIMB CLOSE TO NORMAL. MID AND HIGH CLOUDS WILL BE ON THE
INCREASE THIS AFTERNOON AS LOW PRESSURE WILL STARTS TO ORGANIZE
NEAR THE RED RIVER VALLEY ALONG THE DEVELOPING ARCTIC FRONT. THE
POLAR VORTEX WILL CONTINUE DROPPING SOUTH WITH VERY COLD AIR PUSHING
INTO THE NORTHERN U.S.
TONIGHT...LOW PRESSURE WILL MOVE NORTHEAST ALONG THE STRENGTHENING
ARCTIC FRONT AND MOVE INTO EASTERN ARKANSAS LATE TONIGHT. RAIN WILL
DEVELOP AND SPREAD OVER THE REGION...ESPECIALLY AFTER MIDNIGHT.
TOWARD SUNRISE RAIN MAY START TO CHANGE TO SNOW ACROSS NE AR AS
COLD AIR BEGINS TO SEEP IN. LOWS TEMPS WILL BE QUITE A BIT MILDER
THANKS TO THE SOUTHERLY FLOW...IN THE 30S TO AROUND 40.
SUNDAY...BIG CHANGE IN STORE. LOW PRESSURE WILL MOVE TO THE TN
RIVER BY 18Z AND A POTENT SHORTWAVE WILL RAPIDLY KICK THE ARCTIC
FRONT EAST IN THE WAKE OF THE SURFACE LOW. TEMPS WILL COOL
RAPIDLY INTO THE 20S AS GUSTY NORTHWEST WINDS DEVELOP. RAIN WILL
CHANGE QUICKLY TO SNOW. THERE COULD BE A BRIEF PERIOD OF SLEET AS
THE COLD AIR AT THE SURFACE RUNS AHEAD OF THE COLD AIR ALOFT
LEAVING A WEAK WARM LAYER AROUND 5KFT. THIS WILL NOT LAST LONG
THOUGH. RIGHT NOW IT LOOKS LIKE THE ARCTIC FRONT WILL BE MOVING
INTO THE NW CORNER OF THE MIDSOUTH JUST BEFORE 12Z...MS RIVER
AROUND 18Z AND NE MS BY MID AFTERNOON. MODEL SOUNDINGS SHOW
FAIRLY DEEP MOISTURE FOR A FEW HOURS BEHIND THE FRONT. THIS
COMBINED WITH A POTENT MID LEVEL SHORTWAVE WILL PRODUCE
ACCUMULATING SNOW...ESPECIALLY ACROSS THE NORTHERN TIER WHERE THE
WATCH IS IN EFFECT. AN INCH OR TWO LOOKS POSSIBLE IN MEMPHIS WITH
LESSER AMOUNTS TO THE SOUTH. THE SNOW COMBINED WITH THE RAPIDLY
FALLING TEMPS AND WIND WILL RESULT IN A FLASH FREEZE WITH ROADWAYS
AND BRIDGES BECOMING SLICK QUICKLY.
SUNDAY NIGHT...LINGERING SNOW WILL TAPER OFF ACROSS EASTERN
SECTIONS DURING THE EVENING THOUGH FLURRIES WILL CONTINUE AS VERY
COLD AIR ADVECTS IN ON GUSTY NW WINDS. THE POLAR VORTEX WILL MOVE
INTO THE GREAT LAKES WHILE THE COLDEST AIR SINCE FEB 1996 SETTLES
OVER THE MIDSOUTH. 850MB TEMPS OF -20C OR LOWER AND 1000-500MB
THICKNESS VALUES APPROACHING 500DM. DESPITE THE WIND AND SOME
CLOUDS TEMPS WILL FALL INTO THE SINGLE DIGITS ACROSS MUCH OF THE
AREA BY MONDAY MORNING. WIND CHILLS WILL DROP TO BELOW ZERO ACROSS
THE ENTIRE AREA AND BELOW MINUS 10 NORTH OF I-40. NOW IS THE TIME
TO THINK ABOUT THOSE PIPES.
MONDAY THROUGH TUESDAY NIGHT...VERY COLD. MONDAY WILL BE THE
FIRST DAY MEMPHIS DOES NOT GET OUT OF THE TEENS SINCE FEB 1996.
PLACES UP NORTH WILL PROBABLY STAY IN THE SINGLE DIGITS. MONDAY
NIGHT WILL BE ANOTHER VERY COLD NIGHT AS SURFACE HIGH PRESSURE
WILL BE CENTERED ON THE MIDSOUTH. ANY SNOW ON THE GROUND WILL ONLY
AID RADIATIONAL COOLING AND HELP DROP TEMPS EVEN FURTHER. LOTS OF
SINGLE DIGITS EXPECTED WITH SOME BELOW ZERO READINGS POSSIBLE. THE
COLDEST AIR STARTS TO RETREAT EAST ON TUESDAY THOUGH TEMPS WILL
STILL BE QUITE COLD...IN THE 20S.
WEDNESDAY THROUGH FRIDAY...OVERRUNNING PATTERN SETS UP OVER THE
RETREATING ARCTIC AIRMASS WITH PRECIP CHANCES INCREASING. A
WINTRY MIX WILL BE POSSIBLE ACROSS NORTHERN AREAS WEDNESDAY
THROUGH THURSDAY MORNING WITH CHANCES FOR RAIN ELSW. ENOUGH
WARMING OCCURS FOR ONLY RAIN BY MID MORNING THURSDAY THROUGH
FRIDAY.
SJM
AVIATION...
12Z TAFS
VFR CONDITIONS WILL CONTINUE THROUGH MOST OF THE TAF PERIOD...WITH
CIGS DECREASING TO MVFR AND IFR TONIGHT AS AN ARCTIC COLD FRONT
APPROACHES. RAIN WILL ALSO DEVELOP AHEAD OF THE BOUNDARY...WITH
JBR SEEING THE ACTIVITY FIRST. STRONG SOUTH WINDS WILL BE THE MAIN
WEATHER CONCERN...WITH SUSTAINED WINDS OF 12-18 KTS AND GUSTS
IN THE 18-26 KT RANGE...DEPENDING ON SITE. AS WINDS DECREASE
SOME NEAR SUNSET WIND SHEAR IS EXPECTED TO DEVELOP AT MEM...JBR
AND MKL. FINALLY JUST BEYOND THIS PERIOD RAIN WILL BE CHANGING TO
ACCUMULATING SNOW BEHIND THE FRONT AT JBR FIRST...THEN MEM AND MKL.
JAB
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 49 39 43 10 / 10 60 100 30
MKL 46 38 42 5 / 0 50 100 40
JBR 44 35 35 6 / 10 90 100 20
TUP 48 38 48 9 / 0 30 100 40
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR CLAY-GREENE-LAWRENCE-RANDOLPH.
MO...WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR DUNKLIN-PEMISCOT.
MS...NONE.
TN...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING
FOR CARROLL-DYER-GIBSON-HENRY-LAKE-OBION-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
331 PM CST SAT JAN 4 2014
.TONIGHT AND SUNDAY...FORECAST CONFIDENCE IS HIGH.
WINTER WEATHER ADVISORY FOR WALWORTH...RACINE AND KENOSHA
COUNTIES CONTINUES UNTIL 00Z MONDAY. AREA RADARS SHOWING MORE
BANDS OF LIGHT TO MODERATE SNOW DEVELOPING FROM FAR EASTERN
IOWA...THROUGH NORTHEAST ILLINOIS/FAR SOUTHEAST WISCONSIN...INTO
SOUTHWEST LOWER MICHIGAN.
THIS WAS BEING DRIVEN BY RIGHT ENTRANCE REGION OF 300 MB JET
STREAK...AS WELL AS MODEST LOW TO MID LEVEL FRONTOGENESIS
RESPONSE. THE MID LEVEL FRONTOGENESIS LINGERS ACROSS THE FAR
SOUTHEAST INTO SUNDAY AFTERNOON...WITH 850MB TROUGH/CONVERGENCE
AND LOW LEVEL FRONTOGENESIS RESPONSE ALSO LINGERING INTO TONIGHT.
GOOD UPWARD VERTICAL MOTION SHOWN IN SATURATED AIR COLUMN AND
DENDRITE ZONE ACROSS THE FAR SOUTHEAST COUNTIES THROUGH TONIGHT
AND SUNDAY ON THE NAM. NAM/CANADIAN/ECMWF HAVE QPF LINGERING IN
THE SOUTHEAST THROUGH SUNDAY.
HOWEVER...GFS DRIES OUT LOW AND SOME OF THE MID LEVELS TONIGHT
INTO SUNDAY. THIS RESULTS IN A MAINLY DRY SUNDAY IN THE FAR
SOUTHEAST. HRRR TRYING TO SHOW A PERIOD OF DRY CONDITIONS LATER
THIS EVENING INTO THE OVERNIGHT HOURS BEFORE BRINGING THE SNOW
BACK BY 09Z SUNDAY.
NAM/MESOSCALE MODELS/SOME SREF ENSEMBLES ARE CRANKING OUT QUITE A
BIT OF QPF IN THE FAR SOUTHEAST THROUGH SUNDAY...UP TO AROUND 1/2
INCH IN SOME INSTANCES. FOR NOW...LEANED TOWARD THE WETTER
SOLUTIONS...BUT DID NOT GO QUITE AS HIGH AS THEM WITH QPF AND
SUBSEQUENT SNOW AMOUNTS.
EXPECTING A 3 TO 5 INCH ACCUMULATION NEAR THE BORDER IN KENOSHA
COUNTY THROUGH SUNDAY...TO AROUND AN INCH IN A MILWAUKEE TO BELOIT
LINE...LOWER TO THE NORTH AND WEST. THESE AMOUNTS COULD BE
SOMEWHAT HIGHER IF THE AFOREMENTIONED WETTER LOOKING MODELS
VERIFY...SO INCREASING AMOUNTS AND ADJUSTING HEADLINES ARE
POSSIBLE IN LATER FORECASTS.
STRONG COLD AIR ADVECTION WILL DEVELOP TONIGHT INTO SUNDAY...AS
ARCTIC AIRMASS MOVES INTO THE AREA. WIND CHILLS ARE EXPECTED TO
DROP QUICKLY AWAY IN SOUTH CENTRAL WISCONSIN LATER TONIGHT...AND
ACROSS AREAS AWAY FROM THE LAKE SUNDAY. KEPT WIND CHILL ADVISORIES
GOING FROM PREVIOUS FORECAST. TEMPERATURES WILL DROP QUICKLY
TONIGHT...AND WILL REMAIN NEARLY STEADY SUNDAY WITH COLD AIR
ADVECTION CONTINUING.
.SUNDAY NIGHT THROUGH TUESDAY...FORECAST CONFIDENCE HIGH.
THE FORECAST OF DANGEROUSLY COLD AIR FOR THIS PERIOD REMAINS ON
TRACK. STRONG LOW PRESSURE THAT WILL MOVE UP THE OHIO VALLEY
TONIGHT AND SUNDAY WILL INTENSIFY FURTHER AND LIKELY RETROGRADE A
BIT FARTHER WEST SUNDAY NIGHT INTO MONDAY. THIS MAY ALLOW US TO
ADJUST TEMPS UP A DEGREE OR SO...BUT THE WINDS WILL BE
STRONGER...SO NO NET GAIN ON THOSE BRUTAL WIND CHILL READINGS.
SOME OF THE MODELS SUGGEST THE CHANCE FOR SNOW MAY HANG BACK
ACROSS THE FAR EAST INTO SUNDAY NIGHT DUE TO THE RETROGRADE TRACK
OF THE LOW. I/LL KEEP A VERY SMALL CHANCE IN THE EAST JUST IN
CASE...BUT IT WILL BE MINOR STUFF EITHER WAY.
.WEDNESDAY THROUGH THURSDAY...FORECAST CONFIDNECE IS MEDIUM.
WE START TO SEE A SHIFT TOWARD A WARMER PATTERN BY MID WEEK. TEMPS
TUESDAY NIGHT/WEDNESDAY MORNING WILL STILL BE VERY COLD ABOUT -5
TO -10...COLD BUT A DECENT IMPROVEMENT FROM THE PREVIOUS COUPLE
OF DAYS. A WARM FRONT APPROACHES FROM THE SOUTH AND THIS COUPLED
WITH THE ARRIVAL OF A FAVORABLE ENTRANCE REGION OF AN UPPER JET
SHOULD TRIGGER SOME FRONTOGENESIS AND WARM ADVECTION ACROSS THE
FRONT. ISENTROPICALLY WE START TO SEE SOME DECENT SATURATION AND
ALL THIS COULD RESULT IN SOME LIGHT SNOW WED AND WED NGT WITH ONLY
A SMALL CHANCE LINGERING INTO THURSDAY.
.FRIDAY AND SATURDAY...FORECAST CONFIDENCE IS MEDIUM.
TEMPS ARE EXPECTED TO CLIMB TO NEAR OR SLIGHTLY ABOVE NORMAL BY
THE END OF NEXT WEEK. HIGHS ARE EXPECTED TO CLIMB INTO THE LOWER
TO MID 30S. THIS COMES AS HIGH PRESSURE SLIPS OFF TO THE EAST AND
LOW PRESSURE MOVES ACROSS THE NORTHERN TIER OF THE U.S.
&&
.AVIATION/00Z TAFS/...
EXPECT LIGHT TO MODERATE SNOW TO CONTINUE AT THE EASTERN SITES
TONIGHT AND SUNDAY...WITH MADISON WEST OF THE SNOW.
KENOSHA SHOULD SEE VISIBILITIES DOWN TO AIRFIELD MINIMUMS AT
TIMES FOR MOST OF TONIGHT...AND AROUND OR BELOW ALTERNATE MINIMUMS
LATER TONIGHT AND SUNDAY. SNOWFALL RATES OF 1/4 INCH PER HOUR ARE
EXPECTED TONIGHT...WITH SOME 1/2 INCH PER HOUR RATES POSSIBLE.
TOTAL OF 3 TO 5 INCHES ARE POSSIBLE BY LATE SUNDAY HERE.
MILWAUKEE AND WAUKESHA MAY SEE A BREAK IN THE SNOW THIS EVENING
AND INTO THE OVERNIGHT HOURS...BEFORE IT OCCURS AGAIN LATER
TONIGHT INTO SUNDAY. FOR NOW...KEPT SNOW IN TAFS AS AM DOUBTFUL
THIS WILL OCCUR. RATES WILL BE 1/4 INCH PER HOUR WHEN THE SNOW
FALLS...WITH BRIEF 1/2 INCH PER HOUR RATES POSSIBLE. TOTAL AMOUNTS
OF AROUND AN INCH ARE EXPECTED BY LATE SUNDAY. MADISON SHOULD BE
JUST WEST OF THE SNOW AREA...AND SHOULD NOT SEE ANY ACCUMULATIONS.
SOUTHWEST WINDS WILL SHIFT NORTHWEST EARLY THIS EVENING IN THE
EASTERN SITES...AS COLD FRONT SLIDES SOUTHEAST THROUGH THE AREA.
WINDS WILL BECOME GUSTY BY SUNDAY AFTERNOON. MAY SEE SOME BLOWING
SNOW OCCUR AT THE EASTERN SITES SUNDAY AFTERNOON...BUT
VISIBILITIES SHOULD BE ABOVE 3 MILES.
&&
.MARINE...
SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR SUNDAY...WITH A GALE
WATCH FOR SUNDAY NIGHT THROUGH MONDAY NIGHT...AS A TIGHT PRESSURE
GRADIENT DEVELOPS WITH STRENGTHENING LOW PRESSURE PASSING
SOUTHEAST OF THE REGION. GUSTS MAY REACH GALE FORCE AT TIMES
SUNDAY NIGHT THROUGH MONDAY NIGHT. HIGH WAVES WILL BE LIMITED
TOWARD AND OVER THE OPEN WATERS...IN THE ICE FREE AREAS. GUSTY
WINDS MAY LINGER THROUGH TUESDAY NIGHT...UNTIL STRONG LOW PRESSURE
MOVES AWAY FROM THE REGION.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...WIND CHILL WARNING FROM 6 PM SUNDAY TO NOON CST TUESDAY FOR
WIZ046-047-051-052-056>060-062>072.
WIND CHILL ADVISORY FROM 6 AM TO 6 PM CST SUNDAY FOR WIZ051-058-
063-064-067>069.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST SUNDAY FOR
WIZ046-047-056-057-062.
WINTER WEATHER ADVISORY UNTIL 6 PM CST SUNDAY FOR WIZ070>072.
LM...GALE WATCH FROM SUNDAY EVENING THROUGH LATE MONDAY NIGHT FOR
LMZ643>646.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM CST SUNDAY FOR LMZ643>646.
&&
$$
TONIGHT/SUNDAY AND AVIATION/MARINE...WOOD
SUNDAY NIGHT THROUGH SATURDAY...DAVIS
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 221 PM CST SAT JAN 4 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN ARCTIC COLD
FRONT MOVING EAST OVER NORTHEAST WISCONSIN EARLY THIS AFTERNOON.
EARLIER FREEZING DRIZZLE OVER CENTRAL AND NORTH-CENTRAL WISCONSIN
HAS MOSTLY DISSIPATED...AND ONLY A FEW FLURRIES ARE LEFT OVER THE
NORTH. MEANWHILE...CLEARING SKIES ARE WORKING THEIR WAY WEST FROM
MINNESOTA INTO CENTRAL WISCONSIN...BUT WILL TAKE A FEW MORE HOURS
FOR THE NORTH TO CLEAR. FARTHER EAST...SOUTHWEST WINDS IN THE UPPER
LEVELS ARE KEEPING A MID-LEVEL CLOUD DECK OVER THE LOW STRATUS ALONG
THE FRONT. THIS MID-LEVEL CLOUD DECK WILL HANG AROUND INTO THE
EVENING PERIOD. BEHIND THE FRONT...TEMPERATURES ARE GRADUALLY
FALLING BUT THE ARRIVAL OF THE COLDER AIR OVER THE DAKOTAS AND
SOUTHERN CANADA WITHIN SURFACE HIGH PRESSURE LOOKS DELAYED
SOMEWHAT. THE COLDEST AIR...HOWEVER...STILL RESIDES OVER NORTHERN
SASKATCHEWAN AND IS POISED TO ARRIVE LATE TOMORROW AFTERNOON.
TEMPERATURES AND WIND CHILL VALUES ARE THE MAIN FORECAST CONCERNS IN
THE SHORT TERM AS ARCTIC AIR RETURNS.
TONIGHT...THE ARCTIC FRONT WILL SHIFT EAST ACROSS CENTRAL AND
SOUTHERN GREAT LAKES WHERE A BAND OF SNOW WILL OCCUR. NORTHWEST OF THE
FRONT...ARCTIC HIGH PRESSURE WILL BE BUILDING SOUTHEAST INTO THE
REGION...AND PUSHING IN INCREASING AMOUNTS OF DRIER AIR IN THE LOW
LEVELS. THIS DRY AIR SHOULD HELP ERODE MUCH OF THE LOW CLOUD COVER
BY THE START OF THE EVENING. WITH WINDS A LITTLE TOO WESTERLY FOR
MUCH OF A LAKE EFFECT COMPONENT ACROSS THE SNOW BELTS...THE ONLY
CLOUD COVER WILL BE A BAND OF MID AND HIGH CLOUDS AS UPPER LEVEL
FLOW WILL REMAIN OUT OF THE SOUTHWEST WHICH WILL KEEP SKIES PARTLY
TO MOSTLY CLOUDY. IN REGARDS TO TEMPERATURES...WNW WINDS WILL BE
COLD ADVECTING THROUGH THE NIGHT WITH 850MB TEMPS DROPPING TO 23
BELOW OVER N-C WISCONSIN. TEMPS LAST NIGHT OVER NORTHERN MINNESOTA
WERE ONLY IN THE SINGLE DIGITS ABOVE AND BELOW ZERO...SO AM
CONCERNED ABOUT DROPPING TEMPS TOO MUCH. NOT CONFIDENT OF
DECOUPLING OCCURRING...SO WILL GO WITH LOWS AROUND IN THE NEG TEENS
BELOW ZERO OVER CENTRAL AND NORTH-CENTRAL WISCONSIN TO THE SINGLE
DIGITS ABOVE ZERO ALONG THE LAKE SHORE. AS MENTIONED ABOVE...THE
BITTERLY COLD AIR LOOKS TO BE DELAYED BY A FEW HOURS...AND MAY NOT REACH
WIND CHILL ADVISORY CRITERIA UNTIL 03Z OVER THE WESTERN FORECAST
AREA. WITH COORD FROM FORECAST OFFICES TO THE WEST...WILL DELAY THE
START TIME OF THE WESTERN ADVISORY UNTIL 03Z. THE EAST WILL START
AT 06Z AS PLANNED.
SUNDAY...SKIES WILL CONTINUE TO BE PARTLY TO MOSTLY CLOUDY WITH MID
HIGH CLOUDS OVERHEAD. SHOULD SEE THESE CLOUDS DEPART TO THE
SOUTHEAST BY LATE MORNING OR EARLY AFTERNOON. THEN A LOBE OF THE
POLAR VORTEX WILL SWING SOUTHEAST INTO THE NORTHERN MISSISSIPPI
VALLEY DURING THE AFTERNOON. A SECONDARY SURGE OF ARCTIC AIR WILL
ARRIVE WITH THE POLAR VORTEX...AND TEMPS MAY START THEIR FALL BY
MID-AFTERNOON. OFTEN WITH THE LEADING EDGE OF THESE BITTERLY COLD
AIRMASSES THERE ARE SCT INSTABILITY SNOW SHOWERS AND MODELS ARE
SHOWING HIGHER LOW LEVEL MOISTURE INCOMING TOMORROW AFTERNOON. NOT
SURE IF THIS WILL OCCUR IN THIS CASE SINCE THERE IS NO DEFINED
ARCTIC FRONT...BUT DID SHOW INCREASING CLOUDS LATE IN THE
AFTERNOON. ANOTHER THING TO KEEP TABS ON IS THE NORTHERN EXTENT OF
THE PRECIP TOMORROW AFTERNOON WITH WITH THE CYCLONE MOVING OVER THE
OHIO VALLEY. BOTH THE NAM AND GEM BRING LIGHT PRECIP INTO FAR E-C
WISCONSIN IN THE AFTERNOON...BUT THIS LOOKS TOO FAR INTO THE ARCTIC
AIRMASS. WILL LEAVE POPS OUT. WITH THE FALLING TEMPS IN THE
AFTERNOON...WIND CHILLS WILL BE APPROACHING WARNING CRITERIA OVER
CENTRAL AND NORTH-CENTRAL WISCONSIN BY 00Z MON.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 221 PM CST SAT JAN 4 2014
PROGS STILL PASS THE CORE OF THE POLAR VORTEX OVER THE REGION
SUNDAY NIGHT INTO MONDAY BEFORE LIFTING EASTWARD INTO TUESDAY.
STRONG BAROCLINIC ZONE IN THE LEAD ARCTIC SURFACE FRONT POSITIONED
TO THE SOUTH AND EAST OF THE AREA LATE SUNDAY WILL BE THE FOCUS OF
ANOTHER SURFACE WAVE AND A REGION OF SNOW EARLY SUNDAY EVENING.
WHILE THE GFS KEEPS THIS AREA OF SNOW SOUTH OF THE AREA SUNDAY
EVENING...THE NAM LIFTS THE NORTHERN PERIPHERY OF THIS SNOW INTO
PARTS OF EAST CENTRAL WISCONSIN. FOR THIS SCENARIO TEMPS WOULD BE
A FEW DEGREES WARMER...BUT WINDS WOULD BE STRONGER DUE TO THE
LOCATION OF THE SURFACE WAVE AND PRESSURE GRADIENT. REGARDLESS OF
EITHER SCENARIO...LITTLE CHANGE TO GOING EXTREME COLD WIND CHILL
FORECASTS...SO NO CHANGES TO THE GOING WIND CHILL WARNING
HEADLINES STARTING SUNDAY EVENING.
FOR THE REST OF THE MODELS CONCERNING THIS LIGHT SNOW POTENTIAL
SUNDAY EVENING FOR THE LAKESHORE REGION...THE GEM AND ECMWF ALSO
PRODUCE SOME LIGHT SNOW ALONG THE LAKE SHORE REGION IN THE EVENING
HOURS. PERHAPS THE MODELS ARE PICKING UP A TREND OF A CONVERGENT
REGION DEVELOPING ON THE WEST SIDE OF LAKE MICHIGAN DUE TO THE
STRONGER WINDS ON THE LAKE PULLING AWAY FROM THE AREA. SURFACE
PRESSURE PLOTS SUGGEST A SUBTLE HEIGHT FALL OVER LAKE MICHIGAN AS
WELL. INCREASING UNSTABLE CONDITIONS OVER THE LAKE ALSO DEVELOPING
WITH THE POLAR VORTEX AND BAROCLINIC ZONE APPROACHING. WILL ADD A
SMALL CHANCE FOR SNOW SHOWERS FOR NOW..BUT ITS POSSIBLE THIS MAY
NEED TO BE INCREASED A LITTLE.
UPPER PATTERN GRADUALLY TURNS MORE ZONAL MID WEEK FOR A TURN TO
MORE NORMAL CONDITIONS. A PIECE OF SOUTHERN STREAM ENERGY SLIDES
OVER THE MID MISSISSIPPI VALLEY REGION WEDNESDAY NIGHT INTO
THURSDAY AND ALONG THE H850 FRONTAL BOUNDARY...GLANCING THE SOUTH
HALF OF THE FORECAST REGION WITH LIGHT SNOW. ANOTHER SHORT WAVE
TROUGH MAY SLIDE OVER THE GREAT LAKES REGION FRIDAY NIGHT INTO
SATURDAY FOR ANOTHER CHANCE OF SNOW OR SNOW MIX...OTHERWISE THE
DRIER WESTERLY OR PACIFIC FLOW CONTINUES INTO THE WEEKEND WITH
MODERATING DAY TIME HIGH TEMPERATURES APPROACHING THE LOWER 30S
WITH NO MAJOR WEATHER SYSTEMS NOTED AT THIS TIME.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1118 AM CST SAT JAN 4 2014
BEHIND AN ARCTIC FRONT...WHICH IS MOVING ACROSS CENTRAL AND
NORTHEAST WISCONSIN AT MIDDAY...AREAS OF FREEZING DRIZZLE ARE BECOMING
MORE PATCHY OVER CENTRAL AND NORTH-CENTRAL WISCONSIN. HAVE ENDED
THE FREEZING DRIZZLE MENTION AT THE START OF THE 18Z TAFS...BUT
WILL HAVE TO MONITOR IN CASE NEED TO THROW IN A 1 HR TEMPO GROUP
IF IT CONTINUES LONGER THAN EXPECTED. IN GENERAL...CIGS AND VSBYS
HAVE BEEN TRENDING UPWARD INTO THE MVFR RANGE OVER THE PAST HOUR
AND THIS TREND SHOULD CONTINUE THROUGH THE AFTERNOON AS DRY ARCTIC
AIR FILTERS IN BEHIND THE FRONT. NOT THINKING ANY FREEZING DRIZZLE
WILL MAKE IT INTO THE FOX VALLEY OR NE WISCONSIN THIS AFTERNOON.
OTHERWISE...ANTICIPATE CONDITIONS TO IMPROVE THROUGH THE AFTERNOON
TO VFR BY EARLY THIS EVENING ACROSS THE REGION. VFR CONDITIONS
WILL THEN REMAIN THROUGH THE END OF THE TAF PERIOD WITH ONLY A
BKN-OVC MID AND HIGH DECK OVERHEAD.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WARNING FROM 6 PM SUNDAY TO NOON CST TUESDAY FOR
WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST SUNDAY FOR
WIZ013-020-021-031-037>039-045-048-049-073-074.
WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 6 PM CST SUNDAY
FOR WIZ005-010>012-018-019-030-035-036.
&&
$$
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......MPC